-
-
INTERNET-DRAFT Editor: R. Harrison
-draft-ietf-ldapbis-authmeth-12.txt Novell, Inc.
-Obsoletes: 2829, 2830 August, 2004
+draft-ietf-ldapbis-authmeth-13.txt Novell, Inc.
+Obsoletes: 2829, 2830 October, 2004
Intended Category: Draft Standard
+
LDAP: Authentication Methods
and
Connection Level Security Mechanisms
+
Status of this Memo
+
By submitting this Internet-Draft, I accept the provisions of
Section 4 of RFC 3667. By submitting this Internet-Draft, I certify
that any applicable patent or other IPR claims of which I am aware
have been disclosed, and any of which I become aware will be
disclosed, in accordance with RFC 3668.
+
This document is intended to be, after appropriate review and
revision, submitted to the RFC Editor as a Standard Track document.
Distribution of this memo is unlimited. Technical discussion of
editorial comments directly to the author
<roger_harrison@novell.com>.
+
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that
other groups may also distribute working documents as Internet-
Drafts.
+
Internet-Drafts are draft documents valid for a maximum of six
months and may be updated, replaced, or obsoleted by other documents
at any time. It is inappropriate to use Internet-Drafts as
reference material or to cite them other than as "work in progress."
+
The list of current Internet-Drafts can be accessed at
http://www.ietf.org/ietf/1id-abstracts.txt
+
The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html.
+
Copyright Notice
+
Copyright (C) The Internet Society (2004). All Rights Reserved.
+
Abstract
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This document describes authentication methods and connection level
security mechanisms of the Lightweight Directory Access Protocol
(LDAP).
+
This document details establishment of TLS (Transport Layer
Security) using the StartTLS operation.
+
This document details the simple Bind authentication method
including anonymous, unauthenticated, and plain-text password
mechanisms and the SASL (Simple Authentication and Security Layer)
Bind authentication method including DIGEST-MD5 and EXTERNAL
mechanisms.
+
This document discusses various authentication and authorization
states through which a connection to an LDAP server may pass and the
actions that trigger these state changes.
+
Table of Contents
+
1. Introduction.....................................................3
1.1. Relationship to Other Documents................................5
1.2. Conventions Used in this Document..............................6
3.1.2. StartTLS Response............................................8
3.1.3. TLS Version Negotiation......................................8
3.1.4. Client Certificate...........................................8
- 3.1.5. Discovery of Resultant Security Level........................8
+ 3.1.5. Discovery of Resultant Security Level........................9
3.1.6. Server Identity Check........................................9
- 3.1.7. Refresh of Server Capabilities Information...................9
+ 3.1.7. Refresh of Server Capabilities Information..................10
3.2. Effects of TLS on a Client's Authorization Identity...........10
3.2.1. TLS Connection Establishment Effects........................10
3.2.2. Client Assertion of Authorization Identity..................10
3.2.3. TLS Connection Closure Effects..............................10
- 3.3. TLS Ciphersuites..............................................10
+ 3.3. TLS Ciphersuites..............................................11
3.3.1. TLS Ciphersuites Recommendations............................11
- 4. LDAP Associations...............................................12
- 4.1. Anonymous LDAP Association on Unbound Connections.............12
- 4.2. Anonymous LDAP Association After Failed Bind..................12
+ 4. Associations....................................................12
+ 4.1. Anonymous Association on Unbound Connections..................12
+ 4.2. Anonymous Association After Failed Bind.......................12
4.3. Invalidated Associations......................................12
- 5. Bind Operation..................................................12
+ 5. Bind Operation..................................................13
5.1. Simple Authentication Choice..................................13
5.2. SASL Authentication Choice....................................13
6. Anonymous Authentication Mechanism of Simple Bind...............13
7. Unauthenticated Authentication Mechanism of Simple Bind.........13
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8. Simple Authentication Mechanism of Simple Bind .................14
- 9. SASL Protocol Profile...........................................14
- 9.1. SASL Service Name for LDAP....................................14
+ 9. SASL Protocol Profile...........................................15
+ 9.1. SASL Service Name for LDAP....................................15
9.2. SASL Authentication Initiation and Protocol Exchange..........15
9.3. Octet Where Negotiated Security Mechanisms Take Effect........16
9.4. Determination of Supported SASL Mechanisms....................16
- 9.5. Rules for Using SASL Security Layers..........................16
+ 9.5. Rules for Using SASL Security Layers..........................17
9.6 Support for Multiple Authentications...........................17
- 10. SASL EXTERNAL Mechanism........................................17
+ 10. SASL EXTERNAL Authentication Mechanism.........................17
10.1. Implicit Assertion...........................................17
- 10.2. Explicit Assertion...........................................17
- 10.3. SASL Authorization Identity..................................17
+ 10.2. Explicit Assertion...........................................18
+ 10.3. SASL Authorization Identity..................................18
10.4. SASL Authorization Identity Syntax...........................18
- 11. SASL DIGEST-MD5 Mechanism......................................19
- 12. Security Considerations........................................20
- 12.1. General LDAP Security Considerations.........................20
- 12.1.1.Password-related Security Considerations....................21
- 12.2. StartTLS Security Considerations.............................22
- 12.3. Unauthenticated Mechanism Security Considerations............22
- 12.4. Simple Mechanism Security Considerations.....................23
- 12.5. SASL DIGEST-MD5 Mechanism Security Considerations............23
- 12.6. Related Security Considerations..............................23
- 13. IANA Considerations............................................23
- Acknowledgments....................................................23
- Normative References...............................................24
- Informative References.............................................25
- Author's Address...................................................25
- Appendix A. LDAP Association State Transition Tables...............25
- A.1. LDAP Association States.......................................25
- A.2. Actions that Affect LDAP Association State....................26
- A.3. Decisions Used in Making LDAP Association State Changes.......26
- A.4. LDAP Association State Transition Table.......................27
- Appendix B. Authentication and Authorization Concepts..............27
- B.1. Access Control Policy.........................................28
- B.2. Access Control Factors........................................28
- B.3. Authentication, Credentials, Identity.........................28
- B.4. Authorization Identity........................................28
- Appendix C. RFC 2829 Change History................................29
- Appendix D. RFC 2830 Change History................................33
- Appendix E. RFC 2251 Change History................................33
- Appendix F. Change History to Combined Document....................33
- Intellectual Property Rights.......................................52
+ 11. SASL DIGEST-MD5 Authentication Mechanism.......................19
+ 12. Security Considerations........................................19
+ 12.1. General LDAP Security Considerations.........................19
+ 12.1.1. Password-related Security Considerations...................20
+ 12.2. StartTLS Security Considerations.............................20
+ 12.3. Unauthenticated Mechanism Security Considerations............21
+ 12.4. Simple Mechanism Security Considerations.....................21
+ 12.5. SASL DIGEST-MD5 Mechanism Security Considerations............21
+ 12.6. Related Security Considerations..............................22
+ 13. IANA Considerations............................................22
+ Acknowledgments....................................................22
+ Normative References...............................................22
+ Informative References.............................................23
+ Author's Address...................................................24
+ Appendix A. Association State Transition Tables....................24
+ A.1. Association States............................................24
+ A.2. Actions that Affect Association State.........................25
+ A.3. Decisions Used in Making Association State Changes............25
+ A.4. Association State Transition Table............................25
+ Appendix B. Authentication and Authorization Concepts..............26
+ B.1. Access Control Policy.........................................26
+ B.2. Access Control Factors........................................26
+ B.3. Authentication, Credentials, Identity.........................27
+ B.4. Authorization Identity........................................27
+ Appendix C. RFC 2829 Change History................................27
+ Appendix D. RFC 2830 Change History................................31
+ Appendix E. RFC 2251 Change History................................32
+ Appendix F. Change History to Combined Document....................32
+ Added implementation requirement that server implementations ......45
+ Intellectual Property Rights.......................................45
+
1. Introduction
+
The Lightweight Directory Access Protocol (LDAP) [Roadmap] is a
powerful protocol for accessing directories. It offers means of
+
+
+
+
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+
searching, retrieving and manipulating directory content, and ways
to access a rich set of security functions.
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It is vital that these security functions be interoperable among all
LDAP clients and servers on the Internet; therefore there has to be
a minimum subset of security functions that is common to all
implementations that claim LDAP conformance.
+
Basic threats to an LDAP directory service include:
+
(1) Unauthorized access to directory data via data-retrieval
operations,
+
(2) Unauthorized access to directory data by monitoring others'
access,
+
(3) Unauthorized access to reusable client authentication
information by monitoring others' access,
+
(4) Unauthorized modification of directory data,
+
(5) Unauthorized modification of configuration information,
+
(6) Denial of Service: Use of resources (commonly in excess) in a
manner intended to deny service to others,
+
(7) Spoofing: Tricking a user or client into believing that
information came from the directory when in fact it did not,
either by modifying data in transit or misdirecting the client's
that information came from a particular client when in fact it
came from a hostile entity, and
+
(8) Hijacking: An attacker seizes control of an established protocol
session.
+
Threats (1), (4), (5), (6), (7) are (8) are active attacks. Threats
(2) and (3) are passive attacks.
+
Threats (1), (4), (5) and (6) are due to hostile clients. Threats
(2), (3), (7) and (8) are due to hostile agents on the path between
client and server or hostile agents posing as a server, e.g. IP
spoofing.
+
LDAP offers the following security mechanisms:
+
(1) Authentication by means of the Bind operation. The Bind
operation provides a simple method which supports anonymous,
unauthenticated, and authenticated with password mechanisms, and
the Secure Authentication and Security Layer (SASL) method which
supports a wide variety of authentication mechanisms,
+
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+
+
(2) Mechanisms to support vendor-specific access control facilities
(LDAP does not offer a standard access control facility)
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+ (3) Data integrity protection by means of security layers in TLS or
+ SASL mechanisms,
- (3) Data integrity protection by means of TLS or SASL mechanisms
- with security layers that provide data integrity protection,
- (4) Data confidentiality protection by means of the TLS protocol or
- SASL mechanisms that provide data confidentiality protection,
+ (4) Data confidentiality protection by means of security layers in
+ TLS or SASL mechanisms,
+
(5) Server resource usage limitation by means of administrative
limits configured on the server, and
+
(6) Server authentication by means of the TLS protocol or SASL
mechanism.
+
LDAP may also be protected by means outside the LDAP protocol, e.g.
with IP-level security [RFC2401].
+
At the moment, imposition of access controls is done by means
outside the scope of LDAP.
- It seems clear that allowing implementations, faced with the above
- requirements, to simply pick and choose among the possible
- alternatives is not a strategy that is likely to lead to
- interoperability. In the absence of mandates, clients will be
- written that do not support any security function supported by the
- server, or worse, they will support only clear text passwords that
- provide inadequate security for most circumstances.
+
+ Considering the above requirements, experience has shown that simply
+ allowing implementations to pick and choose among the possible
+ alternatives is not a strategy that leads to interoperability. In
+ the absence of mandates, clients will continue to be written that do
+ not support any security function supported by the server, or worse,
+ they will support only clear text passwords that provide inadequate
+ security for most circumstances.
+
It is desirable to allow clients to authenticate using a variety of
mechanisms including mechanisms where identities are represented as
distinguished names [X.501] [Models] in string form [LDAPDN] or are
used in different systems (e.g. user name in string form). Because
- these authentication mechanisms transmit credentials in plain text
- form and other authentication mechanisms do not provide data
- security services, it is desirable to ensure secure interopability
- by indentifying a mandatory-to-implement mechanism for establishing
- transport-layer security services.
+ some authentication mechanisms transmit credentials in plain text
+ form and/or do not provide data security services, it is necessary
+ to ensure secure interoperability by identifying a mandatory-to-
+ implement mechanism for establishing transport-layer security
+ services.
+
The set of security mechanisms provided in LDAP and described in
this document is intended to meet the security needs for a wide
mechanisms that might be used to achieve a reasonable level of
security in various circumstances.
+
1.1. Relationship to Other Documents
+
This document is an integral part of the LDAP Technical
Specification [Roadmap].
+
This document obsoletes RFC 2829.
+
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+
+
Sections 2 and 4 of RFC 2830 are obsoleted by [Protocol]. The
remainder of RFC 2830 is obsoleted by this document.
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-
1.2. Conventions Used in this Document
+
1.2.1. Glossary of Terms
+
The following terms are used in this document. To aid the reader,
these terms are defined here.
+
- "user" represents any human or application entity which is
accessing the directory using a directory client. A directory
client (or client) is also known as a directory user agent (DUA).
- - "connection" and "LDAP connection" both refer to the underlying
- transport protocol connection between two protocol peers.
+
+ - "connection" refers to the underlying transport protocol
+ connection used to carry the protocol exchange.
+
- "TLS connection" refers to an LDAP connection with TLS
protection [TLS].
- - "association" and "LDAP association" both refer to the
- association of the LDAP connection and its current
- authentication and authorization state.
+
+ - "association" refers to the association that exists between the
+ connection to its current authorization state. As a shorthand,
+ an association with an authorization state of <state> can be
+ referred to as a "<state> association", e.g. an association with
+ an anonymous authorization state is an anonymous association.
+
1.2.2. Security Terms and Concepts
+
In general, security terms in this document are used consistently
with the definitions provided in [RFC2828]. In addition, several
terms and concepts relating to security, authentication, and
unfamiliar with security-related concepts are encouraged to review
Appendix C before reading the remainder of this document.
+
1.2.3. Keywords
+
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119].
+
2. Implementation Requirements
+
LDAP server implementations MUST support the anonymous
authentication mechanism of simple bind (as discussed in Section 6).
+
LDAP implementations that support any authentication mechanism other
than the anonymous authentication mechanism of simple bind MUST
support the DIGEST-MD5 [DIGEST-MD5] mechanism of SASL bind (as
detailed in section 11). DIGEST-MD5 is a reasonably strong
+
+
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+
authentication mechanism that provides (mandatory-to-implement) data
security (data integrity and data confidentiality) services.
+
LDAP impementations SHOULD support the simple (DN and password)
authentication mechanism of simple bind (as detailed in section 8).
-
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-
Implementations that support this mechanism MUST be capable of
protecting it by establishment of TLS (as discussed in section 3) or
other suitable suitable data confidentiality and data integrity
protection (e.g. IPSec).
- Implementations MAY support additional mechanisms of the simple and
- SASL bind choices. Some of these mechanisms are discussed below.
+
+ Implementations MAY support additional authentication mechanisms.
+ Some of these mechanisms are discussed below.
+
LDAP server implementations SHOULD support client assertion of
authorization identity via the SASL EXTERNAL mechanism (sections
3.2.2 and 9).
+
LDAP server implementations SHOULD support the StartTLS operation,
and server implementations that do support the StartTLS operation
MUST support the TLS_DHE_DSS_WITH_3DES_EDE_CBC_SHA ciphersuite.
+
3. StartTLS Operation
+
The Start Transport Layer Security (StartTLS) operation defined in
section 4.14 of [Protocol] provides the ability to establish TLS
[TLS] on an LDAP connection.
+
+ The goals of using the TLS [TLS] protocol with LDAP are to ensure
+ data confidentiality and integrity, and to optionally provide for
+ authentication. TLS expressly provides these capabilities, although
+ the authentication services of TLS are available to LDAP only in
+ combination with the SASL EXTERNAL authentication method (see
+ section 10), and then only if the SASL EXTERNAL implementation
+ chooses to make use of the TLS credentials.
+
+
3.1. Sequencing of the StartTLS Operation
+
This section describes the overall procedures clients and servers
must follow for TLS establishment. These procedures take into
- consideration various aspects of the overall security of the LDAP
- association including discovery of resultant security level and
- assertion of the client's authorization identity.
+ consideration various aspects of the association including discovery
+ of resultant security level and assertion of the client's
+ authorization identity.
- Note that the precise effects, on a client's authorization identity,
- of establishing TLS on an LDAP connection are described in detail in
- section 3.2.
3.1.1. StartTLS Request
+
A client may send the StartTLS extended request at any time after
establishing an LDAP connection, except:
+
- when TLS is currently established on the connection,
- when a multi-stage SASL negotiation is in progress on the
connection, or
- when it has not yet received responses for all operation
requests previously issued on the connection.
+
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+
As described in [Protocol] Section 4.14.2.2, a (detected) violation
of any of these requirements results in a return of the
operationsError resultCode.
+
Client implementers should ensure that they strictly follow these
operation sequencing requirements to prevent interoperability
issues. Operational experience has shown that violating these
requirements causes interoperability issues because there are race
conditions that prevent servers from detecting some violations of
-
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-
these requirements due to server hardware speed, network latencies,
etc.
+
There is no general requirement that the client have or have not
already performed a Bind operation (section 4) before sending a
StartTLS operation request.
+
If the client did not establish a TLS connection before sending a
request and the server requires the client to establish a TLS
connection before performing that request, the server MUST reject
that request by sending a resultCode of confidentialityRequired.
+
3.1.2. StartTLS Response
+
The server will return an extended response with the resultCode of
success if it is willing and able to negotiate TLS.
+
It will return a resultCode other than success (documented in
[Protocol] section 4.13.2.2) if it is unwilling or unable to do so.
- The client's current association is unaffected if a non-success
+ The state of the association is unaffected if a non-success
resultCode is returned.
+
In the successful case, the client (which has ceased to transfer
LDAP requests on the connection) MUST either begin a TLS negotiation
or close the connection. The client will send PDUs in the TLS Record
Protocol directly over the underlying transport connection to the
server to initiate [TLS] negotiation.
+
3.1.3. TLS Version Negotiation
+
Negotiating the version of TLS to be used is a part of the TLS
Handshake Protocol [TLS]. Please refer to that document for details.
+
3.1.4. Client Certificate
- In an LDAP server requests a client to provide its certificate
- during TLS negotiation and the client does not present a suitablle
- certifcate (e.g. one that can be validated), the server MAY use a
+
+ If an LDAP server requests a client to provide its certificate
+ during TLS negotiation and the client does not present a suitable
+ certificate (e.g. one that can be validated), the server may use a
local security policy to determine whether to successfully complete
TLS negotiation.
+
If the client provides a certificate that can be validated,
information in the certificate may be used by the server in
establishing the client's authorization identity by use of the SASL
- external mechanism as discussed in Section 9.
+ EXTERNAL mechanism as discussed in Section 9.
-3.1.5. Discovery of Resultant Security Level
- After a TLS connection is established on an LDAP connection, both
- parties must individually decide whether or not to continue based on
- the security level achieved. The procedure for ascertaining the TLS
- connection's security level is implementation dependent.
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+3.1.5. Discovery of Resultant Security Level
+
+
+ After a TLS connection is established on an LDAP connection, both
+ parties are to individually decide whether or not to continue based
+ on the security level achieved. The procedure for ascertaining the
+ TLS connection's security level is implementation dependent.
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If the client or server decides that the security level is not high
enough for it to continue, it SHOULD gracefully close the TLS
may then close the connection, attempt to StartTLS again, send an
unbind request, or send any other LDAP request.
+
3.1.6. Server Identity Check
+
The client MUST check its understanding of the server's hostname
against the server's identity as presented in the server's
Certificate message in order to prevent man-in-the-middle attacks.
+
Matching is performed according to these rules:
+
- The client MUST use the server name provided by the user (or
other trusted entity) as the value to compare against the server
name as expressed in the server's certificate. A hostname
derived from user input is to be considered provided by the user
only if derived in a secure fashion (e.g., DNSSEC).
+
- If a subjectAltName extension of type dNSName is present in the
certificate, it SHOULD be used as the source of the server's
identity.
+
- The string values to be compared MUST be prepared according to
the rules described in [Matching].
+
- The "*" wildcard character is allowed. If present, it applies
only to the left-most name component.
+
For example, *.bar.com would match a.bar.com and b.bar.com, but
it would not match a.x.bar.com nor would it match bar.com. If
more than one identity of a given type is present in the
certificate (e.g. more than one dNSName name), a match in any
one of the set is considered acceptable.
+
If the hostname does not match the dNSName-based identity in the
certificate per the above check, user-oriented clients SHOULD either
notify the user (clients may give the user the opportunity to
Automated clients SHOULD close the connection, returning and/or
logging an error indicating that the server's identity is suspect.
+
+
+
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+
Beyond the server identity checks described in this section, clients
SHOULD be prepared to do further checking to ensure that the server
is authorized to provide the service it is observed to provide. The
client may need to make use of local policy information in making
this determination.
-3.1.7. Refresh of Server Capabilities Information
-
+3.1.7. Refresh of Server Capabilities Information
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Upon TLS session establishment, the client SHOULD discard or refresh
all information about the server it obtained prior to the initiation
altered any server capabilities information retrieved prior to TLS
establishment.
+
The server may advertise different capabilities after TLS
establishment. In particular, the value of supportedSASLMechanisms
may be different after TLS has been negotiated (specifically, the
EXTERNAL and PLAIN [PLAIN] mechanisms are likely to be listed only
after a TLS negotiation has been performed).
+
3.2. Effects of TLS on a Client's Authorization Identity
+
This section describes the effects on a client's authorization
identity brought about by establishing TLS on an LDAP connection.
The default effects are described first, and next the facilities for
error conditions. Finally, the effects of closing the TLS connection
are described.
+
Authorization identities and related concepts are described in
- Appendix C.
+ Appendix B.
+
3.2.1. TLS Connection Establishment Effects
- The decision to keep or invalidate the established LDAP association
- (section 12) after TLS connection establishment is a matter of local
- server policy.
+
+ The decision to keep or invalidate the established state of the
+ association (section 4.3) after TLS connection establishment is a
+ matter of local server policy.
+
3.2.2. Client Assertion of Authorization Identity
+
After successfully establishing a TLS session, a client may request
that its certificate exchanged during the TLS establishment be
- utilized to determine the authorization identity of the LDAP
- association. The client accomplishes this via an LDAP Bind request
- specifying a SASL mechanism of EXTERNAL [SASL] (section 9).
+ utilized to determine the authorization identity of the association.
+ The client accomplishes this via an LDAP Bind request specifying a
+ SASL mechanism of EXTERNAL [SASL] (section 10).
+
3.2.3. TLS Connection Closure Effects
- The decision to keep or invalidate the established LDAP association
- after TLS closure is a matter of local server policy.
+
+ The decision to keep or invalidate the established state of the
+ association after TLS closure is a matter of local server policy.
+
3.3. TLS Ciphersuites
+
+
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+
Several issues should be considered when selecting TLS ciphersuites
that are appropriate for use in a given circumstance. These issues
include the following:
+
- The ciphersuite's ability to provide adequate confidentiality
protection for passwords and other data sent over the LDAP
connection. Client and server implementers should recognize that
some TLS ciphersuites provide no confidentiality protection
-
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-
while other ciphersuites that do provide confidentiality
protection may be vulnerable to being cracked using brute force
methods, especially in light of ever-increasing CPU speeds that
reduce the time needed to successfully mount such attacks.
+
Client and server implementers should carefully consider the
value of the password or data being protected versus the level
of confidentially protection provided by the ciphersuite to
ensure that the level of protection afforded by the ciphersuite
is appropriate.
+
- The ciphersuite's vulnerability (or lack thereof) to man-in-the-
middle attacks. Ciphersuites vulnerable to man-in-the-middle
attacks SHOULD NOT be used to protect passwords or sensitive
data, unless the network configuration is such that the danger
of a man-in-the-middle attack is tolerable.
+
3.3.1. TLS Ciphersuites Recommendations
+
[[TODO: Kurt will have someone from security to look at this and
will propose how to handle discussion of specific TLS ciphersuites
in this draft.]]
+
As of the writing of this document, the following recommendations
regarding TLS ciphersuites are applicable. Because circumstances are
constantly changing, this list must not be considered exhaustive,
but is hoped that it will serve as a useful starting point for
implementers.
+
The following ciphersuites defined in [TLS] MUST NOT be used for
confidentiality protection of passwords or data:
+
TLS_NULL_WITH_NULL_NULL
TLS_RSA_WITH_NULL_MD5
TLS_RSA_WITH_NULL_SHA
+
The following ciphersuites defined in [TLS] can be cracked easily
(less than a day of CPU time on a standard CPU in 2000) and are NOT
RECOMMENDED for use in confidentiality protection of passwords or
data:
+
TLS_RSA_EXPORT_WITH_RC4_40_MD5
TLS_RSA_EXPORT_WITH_RC2_CBC_40_MD5
TLS_RSA_EXPORT_WITH_DES40_CBC_SHA
TLS_DH_DSS_EXPORT_WITH_DES40_CBC_SHA
TLS_DH_RSA_EXPORT_WITH_DES40_CBC_SHA
+
+
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+
+
TLS_DHE_DSS_EXPORT_WITH_DES40_CBC_SHA
TLS_DHE_RSA_EXPORT_WITH_DES40_CBC_SHA
TLS_DH_anon_EXPORT_WITH_RC4_40_MD5
TLS_DH_anon_EXPORT_WITH_DES40_CBC_SHA
+
The following ciphersuites are vulnerable to man-in-the-middle
attacks:
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-
TLS_DH_anon_EXPORT_WITH_RC4_40_MD5
TLS_DH_anon_WITH_RC4_128_MD5
TLS_DH_anon_EXPORT_WITH_DES40_CBC_SHA
TLS_DH_anon_WITH_DES_CBC_SHA
TLS_DH_anon_WITH_3DES_EDE_CBC_SHA
-4. LDAP Associations
- Every LDAP connection has an associated authentication and
- authorization state referred to as the "LDAP association". The Bind
- operation defined in section 4.2 of [Protocol] and discussed further
- in section 5 below allows authentication information to be exchanged
- between the client and server to set the authentication and
- authorization state and thus establish a new LDAP association.
+4. Associations
+
+
+ Every LDAP connection has an associated authorization state referred
+ to as the "association". The Bind operation defined in section 4.2
+ of [Protocol] and discussed further in section 5 below allows
+ information to be exchanged between the client and server to change
+ the authorization state of the association.
+
+
+4.1. Anonymous Association on Unbound Connections
-4.1. Anonymous LDAP Association on Unbound Connections
Prior to the successful completion of a Bind operation and during
- any subsequent authentication exchange, the session has an anonymous
- LDAP association. Among other things this implies that the client
- need not send a Bind Request in the first PDU of the connection. The
- client may send any operation request prior to binding, and the
- server MUST treat it as if it had been performed after an anonymous
- bind operation (section 6). This authentication state on an LDAP
- association is sometimes referred to as an implied anonymous bind.
+ any subsequent authentication exchange, the association has an
+ anonymous authorization state. Among other things this implies that
+ the client need not send a Bind Request in the first PDU of the
+ connection. The client may send any operation request prior to
+ binding, and the server MUST treat it as if it had been performed
+ after an anonymous bind operation (section 6). This association
+ state is sometimes referred to as an implied anonymous bind.
+
-4.2. Anonymous LDAP Association After Failed Bind
+4.2. Anonymous Association After Failed Bind
- Upon receipt of a Bind request, the LDAP association is moved to an
+
+ Upon receipt of a Bind request, the association is moved to an
anonymous state and only upon successful completion of the
authentication exchange (and the Bind operation) is the association
moved to an authenticated state. Thus, a failed Bind operation
- produces an anonymous LDAP association on the session.
+ produces an anonymous association.
+
4.3. Invalidated Associations
- The server may invalidate the LDAP association at any time, e.g. if
- the established security association between the client and server
- has unexpectedly failed or been compromised. The association
- remains invalidated until the next bind request. While the
- association is invalidated, the server may reject any operation
- request other than Bind, Unbind, and StartTLS by responding with a
- resultCode of strongAuthRequired to indicate that the client needs
- to bind to reestablish its authentication state before the server
- will attempt to perform the requested operation. This behavior is
- explained here to help client implementers properly understand and
- react to this situation.
+
+ The server may move the association to an invalidated state at any
+ time, e.g. if an established security layer between the client and
+ server has unexpectedly failed or been compromised. While the
+ connection has an invalid association, the server may reject any
+ operation request other than Bind, Unbind, and StartTLS by
+ responding with a resultCode of strongAuthRequired to indicate that
+ the server requires stronger authentication before it will attempt
+ to perform the requested operation. In practice, this means that the
+ client needs to bind to(re)establish a suitably strong authorization
+
+
+
+
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+
+
+ state on the association before the server will attempt to perform
+ the requested operation.
+
5. Bind Operation
+
The Bind operation ([Protocol] section 4.2) allows authentication
information to be exchanged between the client and server to
- establish a new LDAP association.
-
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+ establish a new authorization state on the association.
The Bind request typically specifies the desired authentication
specified, the server derives it from the authentication identity in
an implementation-specific manner.
+
If the authorization identity is specified the server MUST verify
that the client's authentication identity is permitted to assume
(e.g. proxy for) the asserted authorization identity. The server
MUST reject the Bind operation with an invalidCredentials resultCode
in the Bind response if the client is not so authorized.
+
5.1. Simple Authentication Choice
+
The simple authentication choice of the Bind Operation provides
three authentication mechanisms:
+
1. an anonymous authentication mechanism (section 6),
+
2. an unauthenticated authentication mechanism (section 7), and
+
3. a simple authentication mechanism using credentials consisting
of a name (in the form of an LDAP distinguished name [LDAPDN])
- and a password (section X).
+ and a password (section 8).
+
5.2. SASL Authentication Choice
+
The sasl authentication choice of the Bind Operation provides
facilities for using any SASL mechanism (sections 9-11) including
authentication mechanisms and other services (e.g. data security
services).
+
6. Anonymous Authentication Mechanism of Simple Bind
+
An LDAP client may use the anonymous authentication mechanism of the
- simple Bind choice to explicitly establish an anonymous LDAP
- association by sending a Bind request with a name value of zero
- length and with the simple authentication choice containing a
- password value of zero length.
+ simple Bind choice to explicitly establish an anonymous association
+ by sending a Bind request with a name value of zero length and with
+ the simple authentication choice containing a password value of zero
+ length.
+
7. Unauthenticated Authentication Mechanism of Simple Bind
+
An LDAP client may use the unauthenticated authentication mechanism
- of the simple Bind choice to establish an anonymous LDAP association
- by sending a Bind request with a name value, a distinguished name in
+ of the simple Bind choice to establish an anonymous association by
+ sending a Bind request with a name value, a distinguished name in
+
+
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+
+
LDAP string form [LDAPDN], of non-zero length, and specifying the
the simple authentication choice containing a password value of zero
length.
+
Unauthenticated binds can have significant security issues (see
- section 14). Servers SHOULD by default reject unauthenticated bind
+ section 12.3). Servers SHOULD by default reject unauthenticated bind
requests with a resultCode of invalidCredentials, and clients may
-
-
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-
need to actively detect situations where they would unintentionally
make an unauthenticated bind request.
+
8. Simple Authentication Mechanism of Simple Bind
+
An LDAP client may use the simple authentication mechanism of the
- simple Bind choice to establish an authenticated LDAP association by
+ simple Bind choice to establish an authenticated association by
sending a Bind request with a name value, a distinguished name in
LDAP string form [LDAPDN], and specifying the simple authentication
choice containing an OCTET STRING password value of non-zero length.
+
Servers that map the DN sent in the bind request to a directory
- entry with an associated set of one or more passwords, will compare
- the presented password to the set of passwords associated with that
- entry. The presented password is considered valid if it matches any
- member of this set.
-
- If the DN is not valid, or the password is not valid for the DN, or
- the server otherwise considers the credentials to be invalid, the
- server is to return the invalidCredentials result code. The server
- is only to return success result code when the credentials are valid
- and the server is willing to provide service to the entity these
- credentials identify.
-
- Server behavior is undefined for Bind requests with a zero-length
- name value and specifying the simple authentication choice with a
- value of non-zero length.
+ entry with an associated set of one or more passwords used with this
+ mechanism, will compare the presented password to that set of
+ passwords. The presented password is considered valid if it matches
+ any member of this set.
+
+
+ If the DN is syntactically invalid, the server returns the
+ invalidDNSyntax result code. If the DN is syntactically correct but
+ not valid for purposes of authentication, or the password is not
+ valid for the DN, or the server otherwise considers the credentials
+ to be invalid, the server returns the invalidCredentials result
+ code. The server is only to return the success result code when the
+ credentials are valid and the server is willing to provide service
+ to the entity these credentials identify.
+
+
+ Server behavior is undefined for bind requests specifying the simple
+ authentication mechanism with a zero-length name value and a
+ password value of non-zero length.
+
+
The simple authentication mechanism of simple bind is not suitable
for authentication in environments where there is no network or
- transport layer confidentiality. LDAP implementations MUST be
- capable of protecting it by establish::qment of TLS (as discussed in
- section 3) or other suitable data confidentiality and data integrity
- protection(e.g. IPSec). LDAP implementations
- SHOULD support authentication with the "simple" authentication
- choice when the connection is protected against eavesdropping using
- TLS, as defined in section 4. LDAP implementations SHOULD NOT
- support authentication with the "simple" authentication choice
- unless the data on the connection is protected using TLS or other
- data confidentiality and data integrity protection.
+ transport layer confidentiality. LDAP implementations SHALL NOT
+ support this mechanism unless they are capable of protecting it by
+ establishment of TLS (as discussed in section 3) or other suitable
+ data confidentiality and data integrity protection(e.g. IPSec). LDAP
+ implementations SHOULD support authentication with the "simple"
+ authentication choice when the connection is protected against
+ eavesdropping using TLS, as defined in section 3. LDAP
+ implementations SHOULD NOT support authentication with the "simple"
+ authentication choice unless the data on the connection is protected
+ using TLS or other data confidentiality and data integrity
+ protection.
+
9. SASL Protocol Profile
+
+
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+
+
LDAP allows authentication via any SASL mechanism [SASL]. As LDAP
includes native anonymous and simple (plain text) authentication
methods, the ANONYMOUS [ANONYMOUS] and PLAIN [PLAIN] SASL mechanisms
are typically not used with LDAP.
+
Each protocol that utilizes SASL services is required to supply
certain information profiling the way they are exposed through the
protocol ([SASL] section 5). This section explains how each of these
profiling requirements are met by LDAP.
-9.1. SASL Service Name for LDAP
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+9.1. SASL Service Name for LDAP
The SASL service name for LDAP is "ldap", which has been registered
- with the IANA as a GSSAPI service name.
+ with the IANA as a SASL service name.
+
9.2. SASL Authentication Initiation and Protocol Exchange
+
SASL authentication is initiated via an LDAP bind request
([Protocol] section 4.2) with the following parameters:
+
- The version is 3.
- The AuthenticationChoice is sasl.
- The mechanism element of the SaslCredentials sequence contains
mechanisms that are defined to have the client send data first
(see [SASL] sections 5 and 5.1).
+
In general, a SASL authentication protocol exchange consists of a
series of server challenges and client responses, the contents of
which are specific to and defined by the SASL mechanism. Thus for
client to send a new bind request with the same sasl mechanism to
continue the authentication process.
+
To the LDAP protocol, these challenges and responses are opaque
binary tokens of arbitrary length. LDAP servers use the
serverSaslCreds field, an OCTET STRING, in a bind response message
protocols where SASL is used, LDAP is not text-based, thus no Base64
transformations are performed on these challenge and response values.
+
Clients sending a bind request with the sasl choice selected SHOULD
send an zero-length value in the name field. Servers receiving a
bind request with the sasl choice selected SHALL ignore any value in
the name field.
+
+
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+
+
A client may abort a SASL bind negotiation by sending a BindRequest
with a different value in the mechanism field of SaslCredentials, or
an AuthenticationChoice other than sasl.
mechanism.
-
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-
The server indicates completion of the SASL challenge-response
exchange by responding with a bind response in which the resultCode
is either success, or an error indication.
+
The serverSaslCreds field in the BindResponse can be used to include
an optional challenge with a success notification for mechanisms
which are defined to have the server send additional data along with
SHALL omit the serverSaslCreds field (rather than including the
field with a zero-length value).
+
9.3. Octet Where Negotiated Security Mechanisms Take Effect
+
SASL security layers take effect following the transmission by the
server and reception by the client of the final successful
BindResponse in the exchange.
- Once a SASL security layer providing integrity or confidentiality
- services takes effect, the layer remains in effect until a new layer
- is installed (i.e. at the first octet following the final
- BindResponse of the bind operation that caused the new layer to take
- effect). Thus, an established SASL security layer is not affected
- by a failed or non-SASL Bind.
+
+ Once a SASL security layer providing data integrity or
+ confidentiality services takes effect, the layer remains in effect
+ until a new layer is installed (i.e. at the first octet following
+ the final BindResponse of the bind operation that caused the new
+ layer to take effect). Thus, an established SASL security layer is
+ not affected by a failed or non-SASL Bind.
+
9.4. Determination of Supported SASL Mechanisms
+
Clients may determine the SASL mechanisms a server supports by
reading the supportedSASLMechanisms attribute from the root DSE
(DSA-Specific Entry) ([Models] section 5.1). The values of this
anonymously-bound client to retrieve the supportedSASLMechanisms
attribute of the root DSE.
+
Because SASL mechanisms provide critical security functions, clients
and servers should be configurable to specify what mechanisms are
acceptable and allow only those mechanisms to be used. Both clients
and servers must confirm that the negotiated security level meets
their requirements before proceeding to use the connection.
+
9.5. Rules for Using SASL Security Layers
+
+
+
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+
+
If a SASL security layer is negotiated, the client SHOULD discard
information about the server it obtained prior to the initiation of
the SASL negotiation and not obtained through secure mechanisms.
+
If a lower level security layer (such as TLS) is negotiated, any
SASL security services SHALL be layered on top of such security
layers regardless of the order of their negotiation. In all other
effect then removing the SASL security service does not affect the
continuing service of TLS and vice versa.
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-
9.6 Support for Multiple Authentications
+
LDAP supports multiple SASL authentications as defined in [SASL]
section 6.3.
-10. SASL EXTERNAL Mechanism
- A client can use the EXTERNAL SASL [SASL] mechanism to request the
+10. SASL EXTERNAL Authentication Mechanism
+
+
+ A client can use the SASL EXTERNAL [SASL] mechanism to request the
LDAP server to authenticate and establish a resulting authorization
identity using security credentials exchanged by a lower security
layer (such as by TLS authentication or IP-level security
[RFC2401]).
- The resulting authentication identity of the LDAP association is
- derived from the security credentials in an implementation-specific
- manner. If the client's authentication credentials have not been
- established at a lower security layer, the SASL EXTERNAL bind MUST
- fail with a resultCode of inappropriateAuthentication. Although
- this situation has the effect of leaving the LDAP association in an
- anonymous state (section 5), the state of any established security
- layer is unaffected.
- A client may either implicitly request that its LDAP authorization
+ The authorization identity used to determine the state of the
+ association is derived from the security credentials in an
+ implementation-specific manner. If the client's authentication
+ credentials have not been established at a lower security layer, the
+ SASL EXTERNAL bind MUST fail with a resultCode of
+ inappropriateAuthentication. Although this situation has the effect
+ of leaving the association in an anonymous state (section 5), the
+ state of any established security layer is unaffected.
+
+
+ A client may either implicitly request that its authorization
identity be derived from its authentication credentials exchanged at
a lower security layer or it may explicitly provide an authorization
identity and assert that it be used in combination with those
authentication credentials. The former is known as an implicit
assertion, and the latter as an explicit assertion.
+
10.1. Implicit Assertion
+
An implicit authorization identity assertion is performed by
invoking a Bind request of the SASL form using the EXTERNAL
mechanism name that does not include the optional credentials octet
according to local policy. The underlying mechanics of how this is
accomplished are implementation specific.
+
10.2. Explicit Assertion
+
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+
+
+
An explicit authorization identity assertion is performed by
invoking a Bind request of the SASL form using the EXTERNAL
mechanism name that includes the credentials octet string. This
- string MUST be constructed as documented in section 3.4.1.
+ string MUST be constructed as documented in section 10.4.
+
10.3. SASL Authorization Identity
+
When the EXTERNAL SASL mechanism is being negotiated, if the
SaslCredentials credentials field is present, it contains an
authorization identity. Other mechanisms define the location of the
-
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-
authorization identity in the credentials field. In either case, the
authorization identity is represented in the authzId form described
below.
+
10.4. SASL Authorization Identity Syntax
+
The authorization identity is a string of UTF-8 [RFC3629] encoded
[Unicode] characters corresponding to the following ABNF [RFC2234]
grammar:
- authzId = dnAuthzId / uAuthzId
- DNCOLON = %x64 %x6e %x3a ; "dn:"
- UCOLON = %x75 %x3a ; "u:"
+ authzId ::= dnAuthzId / uAuthzId
+
+
+ DNCOLON ::= %x64 %x6e %x3a ; "dn:"
+ UCOLON ::= %x75 %x3a ; "u:"
+
; distinguished-name-based authz id.
- dnAuthzId = DNCOLON distinguishedName
+ dnAuthzId ::= DNCOLON distinguishedName
+
; unspecified authorization id, UTF-8 encoded.
- uAuthzId = UCOLON userid
- userid = *UTF8 ; syntax unspecified
+ uAuthzId ::= UCOLON userid
+ userid ::= *UTF8 ; syntax unspecified
+
where the <distinguishedName> production is defined in section 3 of
[LDAPDN] and <UTF8> production is defined in section 1.3 of [Models].
+
In order to support additional specific authorization identity
forms, future updates to this specification may add new choices
supporting other forms of the authzId production.
+
The dnAuthzId choice is used to assert authorization identities in
the form of a distinguished name to be matched in accordance with
the distinguishedNameMatch matching rule [Syntaxes]. The decision to
section 4.2). For this reason there is no requirement that the
asserted dn be that of an entry in the directory.
+
The uAuthzId choice allows clients to assert an authorization
identity that is not in distinguished name form. The format of
userid is defined as only a sequence of UTF-8 [RFC3629] encoded
[Unicode] characters, and any further interpretation is a local
matter. To compare uAuthzID values, each uAuthzID value MUST be
+
+
+
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+
+
prepared using [SASLPrep] and then the two values are compared
octet-wise.
+
For example, the userid could identify a user of a specific
directory service, be a login name, or be an email address. A
uAuthzId SHOULD NOT be assumed to be globally unique.
-11. SASL DIGEST-MD5 Mechanism
-
- LDAP servers that implement any authentication method or mechanism
- other than simple anonymous bind MUST implement the SASL
+11. SASL DIGEST-MD5 Authentication Mechanism
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+ LDAP servers that implement any authentication method or mechanism
+ other than simple anonymous bind MUST implement the SASL
DIGEST-MD5 mechanism [DIGEST-MD5]. This provides client
authentication with protection against passive eavesdropping attacks
but does not provide protection against man-in-the-middle attacks.
DIGEST-MD5 also provides data integrity and data confidentiality
capabilities.
+
Support for subsequent authentication ([DIGEST-MD5] section 2.2) is
OPTIONAL in clients and servers.
+
Implementers must take care to ensure that they maintain the
semantics of the DIGEST-MD5 specification even when handling data
that has different semantics in the LDAP protocol.
equivalent if they represent username values in DIGEST-MD5 because
[SASLPrep] semantics are used by DIGEST-MD5.
+
12. Security Considerations
+
Security issues are discussed throughout this document. The
unsurprising conclusion is that security is an integral and
necessary part of LDAP. This section discusses a number of LDAP-
related security considerations.
+
12.1. General LDAP Security Considerations
+
LDAP itself provides no security or protection from accessing or
updating the directory by other means than through the LDAP
protocol, e.g. from inspection by database administrators. Access
control SHOULD always be applied when reading sensitive information
or updating directory information.
- Servers can minimize denial of service attacks by timing out idle
- connections, and returning the unwillingToPerform resultCode rather
- than performing computationally expensive operations requested by
- unauthorized clients.
+
+
+
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+
+
+ Servers can minimize denial of service attacks by providing the
+ ability to configure and enforce administrative limits on
+ operations, timing out idle connections and returning the
+ unwillingToPerform resultCode rather than performing computationally
+ expensive operations requested by unauthorized clients.
+
A connection on which the client has not established connection
integrity and privacy services (e.g via StartTLS, IPSec or a
these attacks by using data protection services as discussed in this
document.
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+12.1.1. Password-related Security Considerations
-12.1.1.Password-related Security Considerations
LDAP allows multi-valued password attributes. In systems where
entries are expected to have one and only one password,
administrative controls should be provided to enforce this behavior.
+
The use of clear text passwords and other unprotected authentication
credentials is strongly discouraged over open networks when the
underlying transport service cannot guarantee confidentiality.
+
The transmission of passwords in the clear--typically for
authentication or modification--poses a significant security risk.
This risk can be avoided by using SASL authentication [SASL]
mechanisms that do not transmit passwords in the clear or by
- negotiating transport or session layer confidentiality services
+ negotiating transport or session layer data confidentiality services
before transmitting password values.
+
To mitigate the security risks associated with the transfer of
passwords, a server implementation that supports any password-based
authentication mechanism that transmits passwords in the clear MUST
support a policy mechanism that at the time of authentication or
password modification, requires:
+
A StartTLS encryption layer has been successfully negotiated.
+
OR
- Some other confidentiality mechanism that protects the password
- value from snooping has been provided.
+
+ Some other data confidentiality mechanism that protects the
+ password value from snooping has been provided.
+
OR
+
The server returns a resultCode of confidentialityRequired for
the operation (i.e. simple bind with password value, SASL bind
transmitting a password value in the clear, add or modify
including a userPassword value, etc.), even if the password
value is correct.
+
12.2. StartTLS Security Considerations
- The goals of using the TLS [TLS] protocol with LDAP are to ensure
- connection confidentiality and integrity, and to optionally provide
- for authentication. TLS expressly provides these capabilities
- (although the authentication services of TLS are available to LDAP
- only in combination with the SASL EXTERNAL authentication method,
- and then only if the SASL EXTERNAL implementation chooses to make
- use of the TLS credentials).
+
+
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+
+
+
All security gained via use of the StartTLS operation is gained by
the use of TLS itself. The StartTLS operation, on its own, does not
provide any additional security.
-
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-
The level of security provided though the use of TLS depends
directly on both the quality of the TLS implementation used and the
style of usage of that implementation. Additionally, a man-in-the-
connection. For example, the security level of the TLS connection
might have been negotiated down to plaintext.
- Clients SHOULD either warn the user when the security level
- achieved does not provide data confidentiality and/or integrity
- protection, or be configurable to refuse to proceed without an
- acceptable level of security.
+
+ Clients SHOULD by default either warn the user when the security
+ level achieved does not provide an acceptable level of data
+ confidentiality and/or data integrity protection, or be configured
+ to refuse to proceed without an acceptable level of security.
+
Server implementors SHOULD allow server administrators to elect
whether and when data confidentiality and integrity are required, as
- well as elect whether TLS authentication of the client is required.
+ well as elect whether authentication of the client during the TLS
+ handshake is required.
+
Implementers should be aware of and understand TLS security
considerations as discussed in the TLS specification [TLS].
+
12.3. Unauthenticated Mechanism Security Considerations
+
Operational experience shows that clients can (and frequently do)
misuse the unauthenticated authentication mechanism of simple bind
(see section 7). For example, a client program might make a
decision to grant access to non-directory information on the basis
of completing a successful bind operation. LDAP server
- implementations will return a success response to an unauthenticated
+ implementations may return a success response to an unauthenticated
bind request thus leaving the client with the impression that the
server has successfully authenticated the identity represented by
- the user name, when in effect, an anonymous LDAP association has
- been established. Clients that use the results from a simple bind
+ the user name, when in effect, an anonymous association has been
+ established. Clients that use the results from a simple bind
operation to make authorization decisions should actively detect
unauthenticated bind requests (by verifying that the supplied
password is not empty) and react appropriately.
+
12.4. Simple Mechanism Security Considerations
+
The simple authentication mechanism of simple bind discloses the
- password to server, which is an inherent security risk. There are
- other mechanisms such as DIGEST-MD5 that do not disclose password to
- server.
+ password to the server, which is an inherent security risk. There
+ are other mechanisms such as DIGEST-MD5 that do not disclose
+ password to server.
+
12.5. SASL DIGEST-MD5 Mechanism Security Considerations
+
+
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+
+
The SASL DIGEST-MD5 mechanism is prone to the qop substitution
- attack, as discussed in 6.2 of RFC 2831. The qop substitution
- attack can be mitigated (as discussed in 6.2 of RFC 2831).
+ attack, as discussed in 3.6 of [DIGEST-MD5]. The qop substitution
+ attack can be mitigated (as discussed in 3.6 of [DIGEST-MD5]).
+
The SASL DIGEST-MD5 mechanism [DIGEST-MD5] provides client
authentication with protection against passive eavesdropping attacks
but does not provide protection against man-in-the-middle attacks.
-Harrison Expires February 2005 [Page 21]
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-Internet-Draft LDAP Authentication Methods 16 July 2004
-
Implementers should be aware of and understand DIGEST-MD5 security
considerations as discussed in the DIGEST-MD5 specification [DIGEST-
MD5].
+
12.6. Related Security Considerations
+
+
Additional security considerations relating to the various
authentication methods and mechanisms discussed in this document
- apply and can be found in [SASL], [SASLPrep], [StringPrep] and
+ apply and can be found in [SASL], [SASLPrep], [StringPrep] and
[RFC3629].
+
13. IANA Considerations
+
The following IANA considerations apply to this document:
- Please update the GSSAPI service name registry to point to [Roadmap]
- and this document.
+
+ It is requested that the IANA update the LDAP Protocol Mechanism
+ registry to indicate that this document and [Protocol] provide the
+ definitive technical specification for the StartTLS
+ (1.3.6.1.4.1.1466.20037) extended operation.
+
[[TODO: add any missing IANA Considerations.]]
+
Acknowledgments
+
This document combines information originally contained in RFC 2829
and RFC 2830. The editor acknowledges the work of Harald Tveit
Alvestrand, Jeff Hodges, Tim Howes, Steve Kille, RL "Bob" Morgan ,
and Mark Wahl, each of whom authored one or more of these documents.
+
This document is based upon input of the IETF LDAP Revision working
group. The contributions and suggestions made by its members in
shaping the contents and technical accuracy of this document is
greatly appreciated.
+
Normative References
+
[[Note to the RFC Editor: please replace the citation tags used in
referencing Internet-Drafts with tags of the form RFCnnnn.]]
+
[RFC2234] Crocker, D., Ed. and P. Overell, "Augmented BNF for
Syntax Specifications: ABNF", RFC 2234, November 1997.
+
[DIGEST-MD5] Leach, P. C. Newman, and A. Melnikov, "Using Digest
Authentication as a SASL Mechanism", draft-ietf-sasl-
rfc2831bis-xx.txt, a work in progress.
+
+
+Harrison Expires April 2005 [Page 22]
+Internet-Draft LDAP Authentication Methods 25 October 2004
+
+
[RFC2119] Bradner, S., "Key Words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
+
[LDAPDN] Zeilenga, Kurt D. (editor), "LDAP: String
Representation of Distinguished Names", draft-ietf-
ldapbis-dn-xx.txt, a work in progress.
+
[Matching] Hoffman, Paul and Steve Hanna, "Matching Text Strings
in PKIX Certificates", draft-hoffman-pkix-stringmatch-
xx.txt, a work in progress.
-Harrison Expires February 2005 [Page 22]
-\f
-Internet-Draft LDAP Authentication Methods 16 July 2004
-
[Models] Zeilenga, Kurt D. (editor), "LDAP: Directory
Information Models", draft-ietf-ldapbis-models-xx.txt,
a work in progress.
+
[Protocol] Sermersheim, J., "LDAP: The Protocol", draft-ietf-
ldapbis-protocol-xx.txt, a work in progress.
+
[Roadmap] K. Zeilenga, "LDAP: Technical Specification Road Map",
draft-ietf-ldapbis-roadmap-xx.txt, a work in progress.
+
[SASL] Melnikov, A. (editor), "Simple Authentication and
Security Layer (SASL)", draft-ietf-sasl-rfc2222bis-
xx.txt, a work in progress.
+
[SASLPrep] Zeilenga, K., "Stringprep profile for user names and
passwords", draft-ietf-sasl-saslprep-xx.txt, (a work in
progress).
- [StringPrep] M. Blanchet, "Preparation of Internationalized
- Strings ('stringprep')", draft-hoffman-rfc3454bis-
- xx.txt, a work in progress.
+
+ [StringPrep] M. Blanchet, "Preparation of Internationalized Strings
+ ('stringprep')", draft-hoffman-rfc3454bis-xx.txt, a
+ work in progress.
+
[Syntaxes] Legg, S. (editor), "LDAP: Syntaxes and Matching Rules",
draft-ietf-ldapbis-syntaxes-xx.txt, a work in progress.
+
[TLS] Dierks, T. and C. Allen. "The TLS Protocol Version
1.1", draft-ietf-tls-rfc2246-bis-xx.txt, a work in
progress.
+
[RFC3629] Yergeau, F., "UTF-8, a transformation format of ISO
10646", RFC 3629, STD 63, November 2003.
+
[Unicode] The Unicode Consortium, "The Unicode Standard, Version
3.2.0" is defined by "The Unicode Standard, Version
3.0" (Reading, MA, Addison-Wesley, 2000. ISBN 0-201-
"Unicode Standard Annex #28: Unicode 3.2"
(http://www.unicode.org/reports/tr28/).
+
Informative References
+
+
+Harrison Expires April 2005 [Page 23]
+Internet-Draft LDAP Authentication Methods 25 October 2004
+
+
[ANONYMOUS] Zeilenga, K.,"Anonymous SASL Mechanism", draft-
zeilenga-sasl-anon-xx.txt, a work in progress.
+
[RFC2828] Shirey, R., "Internet Security Glossary", RFC 2828, May
2000.
+
[PLAIN] Zeilenga, K.,"Plain SASL Mechanism", draft-zeilenga-
sasl-plain-xx.txt, a work in progress.
-
-Harrison Expires February 2005 [Page 23]
-\f
-Internet-Draft LDAP Authentication Methods 16 July 2004
-
[RFC2401] Kent, S. and R. Atkinson, "Security Architecture for
the Internet Protocol", RFC 2401, November 1998.
+
Author's Address
+
Roger Harrison
Novell, Inc.
1800 S. Novell Place
+1 801 861 2642
roger_harrison@novell.com
-Appendix A. LDAP Association State Transition Tables
+
+Appendix A. Association State Transition Tables
+
This section provides a state transition table to represent a state
- diagram for the various authentication and TLS states through which
- an LDAP association may pass during the course of its existence and
- the actions that cause these changes in state.
+ diagram for the various authentication states through which an
+ association may pass during the course of its existence and the
+ actions that cause these changes in state.
+
This section is based entirely on information found in this document
and other documents that are part of the LDAP Technical
Specification [Roadmap]. As such, it is strictly informational in
nature.
-A.1. LDAP Association States
- The following table lists the valid LDAP association states and
- provides a description of each state. The ID for each state is used
- in the state transition table in section A.4.
+A.1. Association States
+
+
+ The following table lists the valid association states and provides
+ a description of each state. The ID for each state is used in the
+ state transition table in section A.4.
+
ID State Description
-- --------------------------------------------------------------
S3 Authenticated SASL EXTERNAL, implicit authorization ID
Authentication ID = J
Authorization ID = Y
+
+
+
+
+Harrison Expires April 2005 [Page 24]
+Internet-Draft LDAP Authentication Methods 25 October 2004
+
+
S4 Authenticated SASL EXTERNAL, explicit authorization ID Z
Authentication ID = J
Authorization ID = Z
+ S5 Invalidated
-A.2. Actions that Affect LDAP Association State
- The following table lists the actions that can affect the
- authentication and authorization state of an LDAP association. The
- ID for each action is used in the state transition table in section
- A.4.
+A.2. Actions that Affect Association State
+
+ The following table lists the actions that can affect the
+ authentication and authorization state of an association. The ID for
+ each action is used in the state transition table in section A.4.
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ID Action
-- --------------------------------------------------------------
A1 Client bind request fails
- A2 Client successfully performs anonymous simple bind
- A3 Client successfully performs unauthenticated simple bind
- A4 Client successfully performs simple bind with name and password
+ A2 Client successfully performs anonymous simple bind or
+ unauthenticated simple bind
+ A3 Client successfully performs simple bind with name and password
OR SASL bind with any mechanism except EXTERNAL using an
authentication ID = I that maps to authorization ID X
- A5 Client Binds SASL EXTERNAL with implicit assertion of
- authorization ID (section 9.1)]. The current authentication ID
+ A4 Client Binds SASL EXTERNAL with implicit assertion of
+ authorization ID (section 9.1). The current authentication ID
maps to authorization ID = Y.
- A6 Client Binds SASL EXTERNAL with explicit assertion of
- authorization ID = Z (section 9.2)]
- A7 Client StartTLS request fails
- A8 Client StartTLS request succeeds
- A9 Client or Server: graceful TLS removal
+ A5 Client Binds SASL EXTERNAL with explicit assertion of
+ authorization ID = Z (section 9.2).
+ A6 Client StartTLS request fails
+ A7 Client StartTLS request succeeds
+ A8 Client or Server: graceful TLS removal
+ A9 Server decides to invalidate current association state
+
+
+A.3. Decisions Used in Making Association State Changes
-A.3. Decisions Used in Making LDAP Association State Changes
Certain changes in the authentication and authorization state of an
- LDAP association are only allowed if the server can affirmatively
- answer a question. These questions are applied as part of the
- criteria for allowing or disallowing a state transition in the state
- transition table in section A.4.
+ association are only allowed if the server can affirmatively answer
+ a question. These questions are applied as part of the criteria for
+ allowing or disallowing a state transition in the state transition
+ table in section A.4.
+
ID Decision Question
-- --------------------------------------------------------------
D2 Can lower-layer credentials for Auth ID "K" be mapped to
asserted AuthZID "L"?
-A.4. LDAP Association State Transition Table
- The LDAP Association table below lists the the actions that could
- affect authentication and authorization state of an LDAP association
- and the resulting state of an LDAP association after a given action
- occurs.
+A.4. Association State Transition Table
+
+
+ The Association table below lists the the actions that could affect
+ the authorization state of an association and the resulting state of
+ an association after a given action occurs.
+
S1, the initial state for the state machine described in this table,
- is the authentication state when an LDAP connection is initially
+ is the association state when an LDAP connection is initially
established.
- Next
- Action State Comment
- ------- ----- -------------------------------------------------
- A1 S1 Section 4
- A2 S1 Section 6
- A3 S1 Section 7
- A4 S2 Sections 8, 9
- A5, S1 Failed bind, section 10.1
- D1=no
- A5, S3
- D1=yes
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- A6, S1 Failed bind, section 10.2
+Harrison Expires April 2005 [Page 25]
+Internet-Draft LDAP Authentication Methods 25 October 2004
+
+
+ Next State
+ Action Comment
+ ------------------ ----------- --------------------------------
+ A1 S1 Section 4
+ A2 S1 Sections 6 & 7
+ A3 S2 Sections 8, 9
+ A4, S1 Failed bind, section 10.1
+ D1=no
+ A4, S3
+ D1=yes
+ A5, S1 Failed bind, section 10.2
D1=no
- A6, S1 Failed bind, section 10.2
- D1=yes,
+ A5, S1 Failed bind, section 10.2
+ D1=yes,
D2=no
- A6, S4
- D1=yes,
- D2=yes
- A7 no [Protocol] section 4.14.2.2
- change
- A8 no [Protocol] section 4.14.2.1
- change
- A9 S1 [Protocol] section 4.14.3.1
+ A5, S4
+ D1=yes, D2=yes
+ A6 no change* [Protocol] section 4.14.2.2
+ A7 no change* [Protocol] section 4.14.2.1
+ A8 S1 [Protocol] section 4.14.3.1
+ A9 S5
+
+
+ * The server may invalidate the association after TLS
+ establishment or closure (section 3.2).
+
Appendix B. Authentication and Authorization Concepts
+
This appendix defines basic terms, concepts, and interrelationships
regarding authentication, authorization, credentials, and identity.
These concepts are used in describing how various security
approaches are utilized in client authentication and authorization.
+
B.1. Access Control Policy
+
An access control policy is a set of rules defining the protection
of resources, generally in terms of the capabilities of persons or
other entities accessing those resources. Security objects and
mechanisms, such as those described here, enable the expression of
access control policies and their enforcement.
+
B.2. Access Control Factors
+
A request, when it is being processed by a server, may be associated
with a wide variety of security-related factors (section 4.2 of
[Protocol]). The server uses these factors to determine whether and
associated with the connection via which the request is transmitted,
others (e.g. time of day) may be "environmental".
+
Access control policies are expressed in terms of access control
factors. E.g., a request having ACFs i,j,k can perform operation Y
+
+
+Harrison Expires April 2005 [Page 26]
+Internet-Draft LDAP Authentication Methods 25 October 2004
+
+
on resource Z. The set of ACFs that a server makes available for
such expressions is implementation-specific.
+
B.3. Authentication, Credentials, Identity
+
Authentication credentials are the evidence supplied by one party to
another, asserting the identity of the supplying party (e.g. a user)
- who is attempting to establish an association with the other party
- (typically a server). Authentication is the process of generating,
- transmitting, and verifying these credentials and thus the identity
-
-
+ who is attempting to establish a new association state with the
+ other party (typically a server). Authentication is the process of
+ generating, transmitting, and verifying these credentials and thus
+ the identity they assert. An authentication identity is the name
+ presented in a credential.
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-Internet-Draft LDAP Authentication Methods 16 July 2004
-
- they assert. An authentication identity is the name presented in a
- credential.
There are many forms of authentication credentials -- the form used
depends upon the particular authentication mechanism negotiated by
mechanism may constrain the form of authentication identities used
with it.
+
B.4. Authorization Identity
+
An authorization identity is one kind of access control factor. It
is the name of the user or other entity that requests that
operations be performed. Access control policies are often expressed
in terms of authorization identities; e.g., entity X can perform
operation Y on resource Z.
+
The authorization identity bound to an association is often exactly
the same as the authentication identity presented by the client, but
it may be different. SASL allows clients to specify an authorization
server's access control policy, requiring a server-specific mapping
to be done. The method by which a server composes and validates an
authorization identity from the authentication credentials supplied
- by a client is implementation-specific.
+ by a client is performed in an implementation-specific manner.
+
Appendix C. RFC 2829 Change History
+
This appendix lists the changes made to the text of RFC 2829 in
preparing this document.
+
C.0. General Editorial Changes
Version -00
+
- Changed other instances of the term LDAP to LDAP where v3 of the
protocol is implied. Also made all references to LDAP use the
same wording.
+
+
+Harrison Expires April 2005 [Page 27]
+Internet-Draft LDAP Authentication Methods 25 October 2004
+
+
- Miscellaneous grammatical changes to improve readability.
+
- Made capitalization in section headings consistent.
+
Version -01
+
- Changed title to reflect inclusion of material from RFC 2830 and
2251.
-C.1. Changes to Section 1
-Harrison Expires February 2005 [Page 27]
-\f
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+C.1. Changes to Section 1
Version -01
+
- Moved conventions used in document to a separate section.
+
C.2. Changes to Section 2
+
Version -01
+
- Moved section to an appendix.
+
C.3. Changes to Section 3
+
Version -01
+
- Moved section to an appendix.
+
C.4 Changes to Section 4
+
Version -00
+
- Changed "Distinguished Name" to "LDAP distinguished name".
+
C.5. Changes to Section 5
+
Version -00
+
- Added the following sentence: "Servers SHOULD NOT allow clients
with anonymous authentication to modify directory entries or
access sensitive information in directory entries."
+
C.5.1. Changes to Section 5.1
+
Version -00
+
- Replaced the text describing the procedure for performing an
anonymous bind (protocol) with a reference to section 4.2 of RFC
2251 (the protocol spec).
+
Version -01
+
- Brought text describing procedure for performing an anonymous
bind from section 4.2 of RFC 2251 bis. This text will be
removed from the draft standard version of that document.
+
+Harrison Expires April 2005 [Page 28]
+Internet-Draft LDAP Authentication Methods 25 October 2004
+
+
+
C.6. Changes to Section 6.
+
Version -00
+
Reorganized text in section 6.1 as follows:
+
1. Added a new section (6.1) titled "Simple Authentication" and
- moved one of two introductory paragra phs for section 6 into
+ moved one of two introductory paragraphs for section 6 into
section 6.1. Added sentences to the paragraph indicating:
-Harrison Expires February 2005 [Page 28]
-\f
-Internet-Draft LDAP Authentication Methods 16 July 2004
-
a. simple authentication is not suitable for environments where
confidentiality is not available.
+
b. LDAP implementations SHOULD NOT support simple
authentication unless confidentiality and data integrity
mechanisms are in force.
+
2. Moved first paragraph of section 6 (beginning with "LDAP
implementations MUST support authentication with a password...")
to section on Digest Authentication (Now section 6.2).
+
C.6.1. Changes to Section 6.1.
+
Version -00 Renamed section to 6.2
+
- Added sentence from original section 6 indicating that the
DIGEST-MD5 SASL mechanism is required for all conforming LDAP
implementations
+
C.6.2. Changes to Section 6.2
+
Version -00
+
- Renamed section to 6.3
+
- Reworded first paragraph to remove reference to user and the
userPassword password attribute Made the first paragraph more
general by simply saying that if a directory supports simple
following negotiation of a TLS ciphersuite that supports
confidentiality.
+
- Replaced "the name of the user's entry" with "a DN" since not
all bind operations are performed on behalf of a "user."
+
- Added Section 6.3.1 heading just prior to paragraph 5.
+
- Paragraph 5: replaced "The server" with "DSAs that map the DN
sent in the bind request to a directory entry with a
userPassword attribute."
+
C.6.3. Changes to section 6.3.
+
+
+Harrison Expires April 2005 [Page 29]
+Internet-Draft LDAP Authentication Methods 25 October 2004
+
+
Version -00
+
- Renamed to section 6.4.
+
C.7. Changes to section 7.
+
none
-C.7.1. Changes to section 7.1.
+C.7.1. Changes to section 7.1.
-Harrison Expires February 2005 [Page 29]
-\f
-Internet-Draft LDAP Authentication Methods 16 July 2004
Version -00
+
- Clarified the entity issuing a certificate by moving the phrase
"to have issued the certificate" immediately after
"Certification Authority."
+
C.8. Changes to section 8.
+
Version -00
+
- Removed the first paragraph because simple authentication is
covered explicitly in section 6.
+
- Added section 8.1. heading just prior to second paragraph.
+
- Added section 8.2. heading just prior to third paragraph.
+
- Added section 8.3. heading just prior to fourth paragraph.
+
Version -01
+
- Moved entire section 8 of RFC 2829 into section 3.4 (Using SASL
for Other Security Services) to bring material on SASL
mechanisms together into one location.
+
C.9. Changes to section 9.
+
Version -00
+
- Paragraph 2: changed "EXTERNAL mechanism" to "EXTERNAL SASL
mechanism."
+
- Added section 9.1. heading.
+
- Modified a comment in the ABNF from "unspecified userid" to
"unspecified authz id".
+
- Deleted sentence, "A utf8string is defined to be the UTF-8
encoding of one or more ISO 10646 characters," because it is
redundant.
+
- Added section 9.1.1. heading.
+
- Added section 9.1.2. heading.
+
+Harrison Expires April 2005 [Page 30]
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+
+
+
Version -01
+
- Moved entire section 9 to become section 3.5 so that it would be
with other SASL material.
+
C.10. Changes to Section 10.
- Version -00
+ Version -00
-Harrison Expires February 2005 [Page 30]
-\f
-Internet-Draft LDAP Authentication Methods 16 July 2004
- Updated reference to cracking from a week of CPU time in 1997 to
be a day of CPU time in 2000.
+
- Added text: "These ciphersuites are NOT RECOMMENDED for use...
and server implementers SHOULD" to sentence just prior the
second list of ciphersuites.
+
- Added text: "and MAY support other ciphersuites offering
equivalent or better protection," to the last paragraph of the
section.
+
C.11. Changes to Section 11.
+
Version -01
+
- Moved to section 3.6 to be with other SASL material.
+
C.12. Changes to Section 12.
+
Version -00
+
- Inserted new section 12 that specifies when SASL protections
begin following SASL negotiation, etc. The original section 12
is renumbered to become section 13.
+
Version -01
+
- Moved to section 3.7 to be with other SASL material.
+
C.13. Changes to Section 13 (original section 12).
+
None
+
Appendix D. RFC 2830 Change History
+
This appendix lists the changes made to the text of RFC 2830 in
preparing this document.
+
D.0. General Editorial Changes
+
- Material showing the PDUs for the StartTLS response was broken
out into a new section.
+
+
+
+Harrison Expires April 2005 [Page 31]
+Internet-Draft LDAP Authentication Methods 25 October 2004
+
+
- The wording of the definition of the StartTLS request and
StartTLS response was changed to make them parallel. NO changes
were made to the ASN.1 definition or the associated values of
the parameters.
+
- A separate section heading for graceful TLS closure was added
for parallelism with section on abrupt TLS closure.
-Appendix E. RFC 2251 Change History
-
+Appendix E. RFC 2251 Change History
-Harrison Expires February 2005 [Page 31]
-\f
-Internet-Draft LDAP Authentication Methods 16 July 2004
This appendix lists the changes made to the text of RFC 2251 in
preparing this document.
+
E.0. General Editorial Changes
+
- All material from section 4.2 of RFC 2251 was moved into this
document.
+
- A new section was created for the Bind Request
+
- Section 4.2.1 of RFC 2251 (Sequencing Bind Request) was moved
after the section on the Bind Response for parallelism with the
presentation of the StartTLS operations. The section was also
the discussion of the Bind operation (primarily sections 4.4 -
4.7).
+
Appendix F. Change History to Combined Document
+
F.1. Changes for draft-ldap-bis-authmeth-02
+
General
+
- Added references to other LDAP standard documents, to sections
within the document, and fixed broken references.
+
- General editorial changes--punctuation, spelling, formatting,
etc.
+
Section 1.
+
- Added glossary of terms and added sub-section headings
+
Section 2.
+
- Clarified security mechanisms 3, 4, & 5 and brought language in
line with IETF security glossary.
+
Section 3.
+
+
+
+Harrison Expires April 2005 [Page 32]
+Internet-Draft LDAP Authentication Methods 25 October 2004
+
+
- Brought language in requirement (3) in line with security
glossary.
+
- Clarified that information fetched prior to initiation of TLS
negotiation must be discarded
+
-Clarified that information fetched prior to initiation of SASL
negotiation must be discarded
+
- Rewrote paragraph on SASL negotiation requirements to clarify
intent
-Harrison Expires February 2005 [Page 32]
-\f
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-
Section 4.4.
+
- Added stipulation that sasl choice allows for any SASL mechanism
not prohibited by this document. (Resolved conflict between this
statement and one that prohibited use of ANONYMOUS and PLAIN
SASL mechanisms.)
+
Section 5.3.6
+
- Added a.x.bar.com to wildcard matching example on hostname check.
+
Section 6
- - Added LDAP Association State Transition Tables to show the
- various states through which an LDAP association may pass along
- with the actions and decisions required to traverse from state
- to state.
+
+ - Added Association State Transition Tables to show the various
+ states through which an association may pass along with the
+ actions and decisions required to traverse from state to state.
+
Appendix A
+
- Brought security terminology in line with IETF security glossary
throughout the appendix.
+
F.2. Changes for draft-ldapbis-authmeth-03
+
General
+
- Added introductory notes and changed title of document and
references to conform to WG chair suggestions for the overall
technical specification.
+
- Several issues--H.13, H.14, H.16, H.17--were resolved without
requiring changes to the document.
+
Section 3
+
- Removed reference to /etc/passwd file and associated text.
+
Section 4
+
- Removed sections 4.1, 4.2 and parts of section 4.3. This
information was being duplicated in the protocol specification
and will now reside there permanently.
+
+
+Harrison Expires April 2005 [Page 33]
+Internet-Draft LDAP Authentication Methods 25 October 2004
+
+
Section 4.2
+
- changed words, "not recommended" to "strongly discouraged"
+
Section 4.3
+
- Based on ldapbis WG discussion at IETF52 two sentences were
added indicating that clients SHOULD NOT send a DN value when
binding with the sasl choice and servers SHALL ignore any value
received in this circumstance.
-
-Harrison Expires February 2005 [Page 33]
-\f
-Internet-Draft LDAP Authentication Methods 16 July 2004
-
-
+
Section 8.3.1
+
- Generalized the language of this section to not refer to any
specific password attribute or to refer to the directory entry
as a "user" entry.
+
Section 11
+
- Added security consideration regarding misuse of unauthenticated
access.
+
- Added security consideration requiring access control to be
applied only to authenticated users and recommending it be
applied when reading sensitive information or updating directory
information.
+
F.3. Changes for draft-ldapbis-authmeth-04
+
General
+
- Changed references to use [RFCnnnn] format wherever possible.
(References to works in progress still use [name] format.)
- Various edits to correct typos and bring field names, etc. in
line with specification in [Protocol] draft.
+
- Several issues--H.13, H.14, H.16, H.17--were resolved without
requiring changes to the document.
+
Section 4.4.1.
+
- Changed ABNF grammar to use productions that are like those in
the model draft.
+
Section 5
+
- Removed sections 5.1, 5.2, and 5.4 that will be added to
[Protocol]. Renumbered sections to accommodate this change.
-
+
Section 6
- - Reviewed LDAP Association State table for completeness and
- accuracy. Renumbered actions A3, A4, and A5 to be A5, A3, and A4
+
+
+
+Harrison Expires April 2005 [Page 34]
+Internet-Draft LDAP Authentication Methods 25 October 2004
+
+
+ - Reviewed Association State table for completeness and accuracy.
+ Renumbered actions A3, , and A5 to be A5, A3, and A4
respectively. Re-ordered several lines in the table to ensure
that actions are in ascending order (makes analyzing the table
much more logical). Added action A2 to several states where it
was missing and valid. Added actions A7 and A8 placeholders to
states S1, S2, S4 and S5 pending resolution of issue H.28.
- Section 11
-
+ Section 11
-Harrison Expires February 2005 [Page 34]
-\f
-Internet-Draft LDAP Authentication Methods 16 July 2004
- Modified security consideration (originally added in -03)
requiring access control to be applied only to authenticated
-
Section 13
+
- Verified all normative references and moved informative
references to a new section 14.
+
F.4. Changes for draft-ldapbis-authmeth-05
+
General
+
- General editory changes to fix punctuation, spelling, line
length issues, etc.
- Verified and updated intra- and inter-document references
- Document-wide review for proper usage of RFC 2119 keywords with
several changes to correct improper usage.
+
Abstract
- Updated to match current contents of documents. This was needed
due to movement of material on Bind and StartTLS operations to
[Protocol] in this revision.
+
Section 3.
+
- Renamed section to "Rationale for LDAP Security Mechanisms" and
removed text that did not support this theme. Part of the
motivation for this change was to remove the implication of the
other text found in the section that everything in the section
was a requirement
+
- Information from several removed paragraphs that describe
deployment scenarios will be added Appendix A in the next
revision of the draft.
+
- Paragraph beginning, " If TLS is negotiated, the client MUST
discard all information..." was moved to section 5.1.7 and
integrated with related material there.
+
+
+Harrison Expires April 2005 [Page 35]
+Internet-Draft LDAP Authentication Methods 25 October 2004
+
+
- Paragraph beginning, "If a SASL security layer is negotiated..."
was moved to section 4.2
+
Section 4.l.
+
- Changed wording of first paragraph to clarify meaning.
+
Section 4.2.
- Added paragraph from section 3 of -04 beginning, "If a SASL
security layer is negotiated..."
-Harrison Expires February 2005 [Page 35]
-\f
-Internet-Draft LDAP Authentication Methods 16 July 2004
-
Section 4.3.3.
- Renamed to "Other SASL Mechanisms" and completely rewrote the
section (one sentence) to generalize the treatment of SASL
mechanisms not explicitly mentioned in this document.
+
Section 4.4.1.
+
- Added paragraph beginning, "The dnAuthzID choice allows client
applications..." to clarify whether DN form authorization
identities have to also have a corresponding directory entry.
This change was based on editor's perception of WG consensus.
+
- Made minor clarifying edits in the paragraph beginning, "The
uAuthzID choice allows for compatibility..."
+
Section 5.1.1.
+
- Made minor clarifying edits in the last paragraph of the
section.
+
Section 5.1.7.
+
- Wording from section 3 paragraph beginning " If TLS is
negotiated, the client MUST discard all information..." was
moved to this section and integrated with existing text.
+
Section 5.2.
+
- Changed usage of "TLS connection" to "TLS session" throughout.
+
- Removed empty section 5.2.1 and renumbered sections it had
previously contained.
+
Section 8.
+
- Added introductory paragraph at beginning of section.
+
Section 8.1.
+
- Changed term "data privacy" to "data confidentiality" to be
consistent with usage in rest of document.
+
Section 8.2.
+
+Harrison Expires April 2005 [Page 36]
+Internet-Draft LDAP Authentication Methods 25 October 2004
+
+
+
- Changed first paragraph to require implementations that
implement *password-based* authentication to implement and
support DIGEST-MD5 SASL authentication.
+
Section 11.
+
- First paragraph: changed "session encryption" to "session
confidentiality protection" to be consistent with usage in rest
of document.
-Harrison Expires February 2005 [Page 36]
-\f
-Internet-Draft LDAP Authentication Methods 16 July 2004
-
Appendix B.
+
- Began changes to incorporate information on deployment scenarios
removed from section 3.
+
F.5. Changes for draft-ldapbis-authmeth-06
+
General
+
- Combined Section 2 (Introduction) and Section 3 (Motivation) and
moved Introduction to section 1. All following sections numbers
were decremented by one as result.
+
- Edits to fix typos, I-D nits, etc.
+
- Opened several new issues in Appendix G based on feedback from
WG. Some of these have been resolved. Others require further
discussion.
+
Section 1
+
- Added additional example of spoofing under threat (7).
+
Section 2.1
- - Changed definition of "LDAP association" and added terms,
+
+ - Changed definition of "association" and added terms,
"connection" and "TLS connection" to bring usage in line with
[Protocol].
+
Section 4.1.6
+
- Clarified sentence stating that the client MUST NOT use derived
forms of DNS names.
+
Section 5.1
- - Began edits to LDAP Association state table to clarify meaning
- of various states and actions.
+
+ - Began edits to association state table to clarify meaning of
+ various states and actions.
+
- Added action A9 to cover abandoned bind operation and added
appropriate transitions to the state transition table to
accommodate it.
+
+
+Harrison Expires April 2005 [Page 37]
+Internet-Draft LDAP Authentication Methods 25 October 2004
+
+
Section 7.2
+
- Replaced first paragraph to clarify that the "DIGEST-MD5" SASL
mechanism is required to implement.
+
Section 9
+
- Rewrote the section to make the advice more applicable over the
long term, i.e. more "timeless." The intent of content in the
original section was preserved.
-Harrison Expires February 2005 [Page 37]
-\f
-Internet-Draft LDAP Authentication Methods 16 July 2004
-
Section 10
+
- Added a clarifying example to the consideration regarding misuse
of unauthenticated access.
+
F.6. Changes for draft-ldapbis-authmeth-07
+
General
+
- Updated external and internal references to accommodate changes
in recent drafts.
+
- Opened several new issues in Appendix G based on feedback from
WG. Some of these have been resolved. Others require further
discussion.
+
Section 3
+
- Rewrote much of section 3.3 to meet the SASL profile
requirements of draft-ietf-sasl-rfc2222bis-xx.txt section 5.
+
- Changed treatement of SASL ANONYMOUS and PLAIN mechanisms to
bring in line with WG consensus.
+
Section 4
+
- Note to implementers in section 4.1.1 based on operational
experience.
+
- Clarification on client continuing by performing a StartTLS with
TLS already established in section 4.1.4.
+
- Moved verification of mapping of client's authentication ID to
asserted authorization ID to apply only to explicit assertion.
The local policy in place for implicit assertion is adequate.
+
Section 7
+
- Removed most of section 7.2 as the information is now covered
adequately via the new SASL profile in section 3.3. Added note
to implementors regarding the treatment of username and realm
values in DIGEST-MD5.
+
+
+Harrison Expires April 2005 [Page 38]
+Internet-Draft LDAP Authentication Methods 25 October 2004
+
+
- Section 7.3. Minor clarifications in wording.
+
- Section 7.3.1. Clarification that a match of the presented value
to any member of the set of stored passwords constitutes a
successful authentication.
+
F.7. Changes for draft-ldapbis-authmeth-08
- General
+ General
-Harrison Expires February 2005 [Page 38]
-\f
-Internet-Draft LDAP Authentication Methods 16 July 2004
- Changed usage from LDAPv3 to LDAP for usage consistency across
LDAP technical specification.
+
- Fixed a number of usage nits for consistency and to bring doc in
conformance with publication guidelines.
+
Abstract
+
- Significant cleanup and rewording of abstract based on WG
feedback.
+
Section 2.1
+
- New definition of user.
+
Section 3
+
- Added 1.5 sentences at end of introductory paragraph indicating
- the effect of the Bind op on the LDAP association.
+ the effect of the Bind op on the association.
+
Section 3.1
+
- Retitled section and clarified wording
+
Section 3.2
+
- Clarified that simple authentication choice provides three types
of authentication: anonymous, unauthenticated, and simple
password.
+
Section 3.3.3
+
- New wording clarifying when negotiated security mechanisms take
effect.
+
Section 3.3.5
+
- Changed requirement to discard information about server fetched
prior to SASL negotiation from MUST to SHOULD to allow for
information obtained through secure mechanisms.
+
Section 3.3.6
+
+
+
+Harrison Expires April 2005 [Page 39]
+Internet-Draft LDAP Authentication Methods 25 October 2004
+
+
- Simplified wording of first paragraph based on suggestion from
WG.
+
Section 3.4
+
- Minor clarifications in wording.
- Section 3.4.1
-
- - Minor clarifications in wording in first sentence.
+ Section 3.4.1
-Harrison Expires February 2005 [Page 39]
-\f
-Internet-Draft LDAP Authentication Methods 16 July 2004
+ - Minor clarifications in wording in first sentence.
- Explicitly called out that the DN value in the dnAuthzID form is
to be matched using DN matching rules.
- Called out that the uAuthzID MUST be prepared using SASLprep
- Clarified requirement on assuming global uniqueness by changing
a "generally... MUST" wording to "SHOULD".
+
Section 4.1.1
+
- Simplified wording describing conditions when StartTLS cannot be
sent.
- Simplified wording in note to implementers regarding race
condition with outstanding LDAP operations on connection.
+
Section 4.1.5
+
- Removed section and moved relevant text to section 4.2.2.
+
Section 4.1.6
+
- Renumbered to 4.1.5.
- Updated server identity check rules for server's name based on
WG list discussion.
+
Section 4.1.7
+
- Renumbered to 4.1.6
- Changed requirement to discard information about server fetched
prior to TLS negotion from MUST to SHOULD to allow for
information obtained through secure mechanisms.
+
Section 6.1
+
- Clarified wording.
- Added definition of anonymous and unauthenticated binds.
+
Section 10
+
- Added security consideration (moved from elsewhere) discouraging
use of cleartext passwords on unprotected communication
channels.
+
Section 11
+
+
+Harrison Expires April 2005 [Page 40]
+Internet-Draft LDAP Authentication Methods 25 October 2004
+
+
- Added an IANA consideration to update GSSAPI service name
registry to point to [Roadmap] and [Authmeth]
+
F.8. Changes for draft-ldapbis-authmeth-09
+
General
+
- Updated section references within document
- Changed reference tags to match other docs in LDAP TS
- Used non-quoted names for all SASL mechanisms
-Harrison Expires February 2005 [Page 40]
-\f
-Internet-Draft LDAP Authentication Methods 16 July 2004
-
Abstract
+
- Inspected keyword usage and removed several improper usages.
+
- Removed sentence saying DIGEST-MD5 is LDAP's mandatory-to-
implement mechanism. This is covered elsewhere in document.
+
- Moved section 5, authentication state table, of -08 draft to
section 8 of -09 and completely rewrote it.
+
Section 1
+
- Reworded sentence beginning, "It is also desirable to allow
- authentication methods to carry identities based on existingù
+ authentication methods to carry identities based on existing,
non-LDAP DN-forms..."
- Clarified relationship of this document to other documents in
the LDAP TS.
+
Section 3.3.5
+
- Removed paragraph beginning,"If the client is configured to
support multiple SASL mechanisms..." because the actions
specified in the paragraph do not provide the protections
server should allow specification of acceptable mechanisms and
only allow those mechanisms to be used.
+
- Clarified independent behavior when TLS and SASL security layers
are both in force (e.g. one being removed doesn't affect the
other).
+
Section 3.3.6
+
- Moved most of section 4.2.2, Client Assertion of Authorization
Identity, to sections 3.3.6, 3.3.6.1, and 3.3.6.2.
+
Section 3.3.6.4
+
- Moved some normative comments into text body.
+
Section 4.1.2
+
+
+
+Harrison Expires April 2005 [Page 41]
+Internet-Draft LDAP Authentication Methods 25 October 2004
+
+
- Non success resultCode values are valid if server is *unwilling*
or unable to negotiate TLS.
+
Section 4.2.1
+
- Rewrote entire section based on WG feedback.
+
Section 4.2.2
- - Moved most of this section to 3.3.6 for better document flow.
+ - Moved most of this section to 3.3.6 for better document flow.
-Harrison Expires February 2005 [Page 41]
-\f
-Internet-Draft LDAP Authentication Methods 16 July 2004
Section 4.2.3
+
- Rewrote entire section based on WG feedback.
+
Section 5.1
+
- Moved imperative language regarding unauthenticated access from
security considerations to here.
+
Section 6
+
- Added several paragraphs regarding the risks of transmitting
passwords in the clear and requiring server implementations to
provide a specific configuration that reduces these risks.
+
Section 6.2
+
- Added sentence describing protections provided by DIGEST-MD5
method.
- Changed DNs in exmple to be dc=example,dc=com.
+
Section 10
+
- Updated consideration on use of cleartext passwords to include
other unprotected authentication credentials
- Substantial rework of consideration on misuse of unauthenticated
bind.
+
F.9. Changes for draft-ldapbis-authmeth-10
+
- Reorganized content of sections 3-9 to improve document flow and
reduce redundancy.
- - Resolved issue of effect of Start TLS and TLS closure on LDAP
+ - Resolved issue of effect of Start TLS and TLS closure on
association state.
- Made numerous minor wording changes based on WG feedback.
- Updated list of threats for Section 1.
- Moved authentication state table to appendix and relettered
appendices.
+
F.10. Changes for draft-ldapbis-authmeth-11
+
+
+Harrison Expires April 2005 [Page 42]
+Internet-Draft LDAP Authentication Methods 25 October 2004
+
+
General
+
- Many editorial changes throughout to clarify wording and better
express intent, primarily based on suggestions from WG mail
list.
document, e.g. "Anonymous Authentication Mechanism of the Simple
Bind Choice".
- Section 1
+ Section 1
-Harrison Expires February 2005 [Page 42]
-\f
-Internet-Draft LDAP Authentication Methods 16 July 2004
- Editorial changes to add clarity.
- Moved section 2 of authmeth -09 into section 1
+
Section 2
+
- New section outlining implementation requirements.
+
Section 3.1.1
+
- Editorial clarification on need for following operation
sequencing requirements.
+
Section 3.1.4
+
- New section added to describe use of client certificates with
StartTLS. Incorporates material moved from other sections of
authmeth -09.
+
Section 4
- - New section added to discuss LDAP Associations. Related material
- was moved from various other sections of authmeth -09 and
+ - New section added to discuss associations. Related material was
+ moved from various other sections of authmeth -09 and
incorporated into this new section.
+
Section 5
+
- Added several paragraphs regarding transmission and derivation
of authentication and authorization identities using the Bind
operation.
+
Section 8
+
- Clarified rules for determining valid credentials and situations
where invalidCredentials result is to be returned.
+
Section 14
+
- Added three security considerations based on WG feedback.
+
Appendix A
+
- Simplfied state tables by removing two unnecessary actions from
the actions table, and removing the current state column of the
+
+
+
+Harrison Expires April 2005 [Page 43]
+Internet-Draft LDAP Authentication Methods 25 October 2004
+
+
state transition table. Updated references to authmeth and
[Protocol].
+
F.11. Changes for draft-ldapbis-authmeth-12
+
General
+
- Changed refererences from Start TLS to StartTLS.
- Removed Appendix B: Example Deployment Scenarios
- Removed Appendix H as all issues listed in the appendix are now
resolved.
-Harrison Expires February 2005 [Page 43]
-\f
-Internet-Draft LDAP Authentication Methods 16 July 2004
-
Section 2
+
- Added implementation requirement that server implementations
that SUPPORT StartTLS MUST support the
TLS_DHE_DSS_WITH_3DES_EDE_CBC_SHA ciphersuite.
+
Section 3.1.2
+
- Added wording clarifying that a client's association is
unaffected if a non-success resultCode is returned in the
StartTLS response.
+
Section 9.2
+
- Final paragraph of this section details requirements for
serverSaslCreds field when no challenge value is sent.
+
Section 10
+
- Clarified language on uAuthzID usage.
+
Section 12
+
- Moved entire section into security considerations. New section
number is 12.1.1.
- Reorganized security considerations by topic.
- Added several security considerations based on WG feedback.
+
Section 13
+
- Moved section to become section 3.3.
+
+F.12. Changes for draft-ldapbis-authmeth-13
+
+
+ General
+
+
+ - General edits for clarity and to remove errors.
+ - Reworded definition of association (section 1.2) and reworked
+ usage of association throughout document. Current semantics:
+ every connection has an association with the same lifetime as
+ the connection, and that association passes through various
+ authorization states.
+
+
+Harrison Expires April 2005 [Page 44]
+Internet-Draft LDAP Authentication Methods 25 October 2004
+
+
+ - Made usage of data confidentiality consistent throughout
+ document.
+
+
+ Section 1
+ - Reworded mechanisms 3 and 4 for more parallelism.
+ - Changed language on rationale for required mechansisms from
+ future to past tense.
+
+
+ Section 2
+ - Clarified that implementations may support any additional
+ authentication mechanism, not just mechanisms associated with
+ simple and SASL bind choices.
+
+
+ Section 3
+ - Moved paragraph explaining goals for using TLS with LDAP from
+ security considerations to here.
+
+
+ Section 4.3
+ - Reworked text to better explain meaning of strongAuthRequired
+ result code when for invalidated associations.
+
+
+ Section 8
+ - Clarified action when simple bind request has a DN with invalid
+ syntax.
+
+
+ Section 12.1
+ - Added ability to configure and enforce administrative service
+ limits as a way to protect against denial of service attacks.
+
+
+ Section 12.2
+ - Clarified that this security consideration relates to performing
+ client authentication during the TLS handshake and not to
+ subsequent SASL EXTERNAL authentication.
+
+
+ Appendix A
+ - Updated tables by collapsing identical states and actions. Also
+ added an invalidated association state and accompanying actions.
+
+
+Added implementation requirement that server implementations
+
+
Intellectual Property Rights
+
The IETF takes no position regarding the validity or scope of any
Intellectual Property Rights or other rights that might be claimed
to pertain to the implementation or use of the technology described
Information on the procedures with respect to rights in RFC
documents can be found in BCP 78 and BCP 79.
+
Copies of IPR disclosures made to the IETF Secretariat and any
assurances of licenses to be made available, or the result of an
attempt made to obtain a general license or permission for the use
+
+
+Harrison Expires April 2005 [Page 45]
+Internet-Draft LDAP Authentication Methods 25 October 2004
+
+
of such proprietary rights by implementers or users of this
specification can be obtained from the IETF on-line IPR repository
at http://www.ietf.org/ipr.
+
The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary
rights that may cover technology that may be required to implement
-
-
-Harrison Expires February 2005 [Page 44]
-\f
-Internet-Draft LDAP Authentication Methods 16 July 2004
-
this standard. Please address the information to the IETF at ietf-
ipr@ietf.org.
+
Full Copyright Statement
+
Copyright (C) The Internet Society (2004). This document is subject
to the rights, licenses and restrictions contained in BCP 78, and
except as set forth therein, the authors retain all their rights.
+
This document and the information contained herein are provided on
an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE
REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE
-
-
-
-
-
-
-
-Harrison Expires February 2005 [Page 45]
-\f
+Harrison Expires April 2005 [Page 46]
\ No newline at end of file
-
-
-
-
-
-
INTERNET-DRAFT Editor: Kurt D. Zeilenga
Intended Category: Standard Track OpenLDAP Foundation
-Expires in six months 15 February 2004
+Expires in six months 24 October 2004
Obsoletes: 2253
+
LDAP: String Representation of Distinguished Names
- <draft-ietf-ldapbis-dn-13.txt>
+ <draft-ietf-ldapbis-dn-15.txt>
+
Status of Memo
- This document is an Internet-Draft and is in full conformance with all
- provisions of Section 10 of RFC2026.
This document is intended to be, after appropriate review and
revision, submitted to the RFC Editor as a Standard Track document
<ietf-ldapbis@openldap.org>. Please send editorial comments directly
to the document editor <Kurt@OpenLDAP.org>.
+
+ By submitting this Internet-Draft, I accept the provisions of Section
+ 4 of RFC 3667. By submitting this Internet-Draft, I certify that any
+ applicable patent or other IPR claims of which I am aware have been
+ disclosed, or will be disclosed, and any of which I become aware will
+ be disclosed, in accordance with RFC 3668.
+
+
Internet-Drafts are working documents of the Internet Engineering Task
- Force (IETF), its areas, and its working groups. Note that other
+ Force (IETF), its areas, and its working groups. Note that other
groups may also distribute working documents as Internet-Drafts.
+
+
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
- time. It is inappropriate to use Internet-Drafts as reference
- material or to cite them other than as ``work in progress.''
+ time. It is inappropriate to use Internet-Drafts as reference material
+ or to cite them other than as "work in progress."
+
The list of current Internet-Drafts can be accessed at
- <http://www.ietf.org/ietf/1id-abstracts.txt>. The list of
+ <http://www.ietf.org/ietf/1id-abstracts.txt>. The list of
Internet-Draft Shadow Directories can be accessed at
<http://www.ietf.org/shadow.html>.
+
Copyright (C) The Internet Society (2004). All Rights Reserved.
+
Please see the Full Copyright section near the end of this document
for more information.
-
-
-
Zeilenga LDAP: Distinguished Names [Page 1]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-dn-13.txt 15 Febrary 2004
+INTERNET-DRAFT draft-ietf-ldapbis-dn-15.txt 24 October 2004
+
Abstract
+
The X.500 Directory uses distinguished names (DNs) as primary keys to
entries in the directory. This document defines the string
representation used in the Lightweight Directory Access Protocol
names, while being able to represent any distinguished name.
+
1. Background and Intended Usage
+
In X.500-based directory systems [X.500], including those accessed
using the Lightweight Directory Access Protocol (LDAP) [Roadmap],
distinguished names (DNs) are used to unambiguously refer to directory
entries [X.501][Models].
+
The structure of a DN [X.501] is described in terms of ASN.1 [X.680].
In the X.500 Directory Access Protocol [X.511] (and other ITU-defined
directory protocols), DNs are encoded using the Basic Encoding Rules
(BER) [X.690]. In LDAP, DNs are represented in the string form
described in this document.
+
It is important to have a common format to be able to unambiguously
represent a distinguished name. The primary goal of this
specification is ease of encoding and decoding. A secondary goal is
translations (such as expressing attribute type names in the local
national language).
+
This document defines the string representation of Distinguished Names
used in LDAP [Protocol][Syntaxes]. Section 2 details the RECOMMENDED
algorithm for converting a DN from its ASN.1 structured representation
to a string. Section 3 details how to convert a DN from a string to a
ASN.1 structured representation.
+
While other documents may define other algorithms for converting a DN
from its ASN.1 structured representation to a string, all algorithms
MUST produce strings which adhere to the requirements of Section 3.
+
This document does not define a canonical string representation for
DNs. Comparison of DNs for equality is to be performed in accordance
with the distinguishedNameMatch matching rule [Syntaxes].
+
This document is an integral part of the LDAP Technical Specification
[Roadmap]. This document obsoletes RFC 2253. Changes since RFC 2253
+
Zeilenga LDAP: Distinguished Names [Page 2]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-dn-13.txt 15 Febrary 2004
+INTERNET-DRAFT draft-ietf-ldapbis-dn-15.txt 24 October 2004
+
are summarized in Appendix B.
+
This specification assumes familiarity with X.500 [X.500] and the
concept of Distinguished Name [X.501][Models].
+
1.1. Conventions
+
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in BCP 14 [RFC2119].
+
Character names in this document use the notation for code points and
names from the Unicode Standard [Unicode]. For example, the letter
"a" may be represented as either <U+0061> or <LATIN SMALL LETTER A>.
+
Note: a glossary of terms used in Unicode can be found in [Glossary].
Information on the Unicode character encoding model can be found in
[CharModel].
+
2. Converting DistinguishedName from ASN.1 to a String
+
X.501 [X.501] defines the ASN.1 [X.680] structure of distinguished
name. The following is a variant provided for discussion purposes.
+
DistinguishedName ::= RDNSequence
+
RDNSequence ::= SEQUENCE OF RelativeDistinguishedName
+
RelativeDistinguishedName ::= SET SIZE (1..MAX) OF
AttributeTypeAndValue
+
AttributeTypeAndValue ::= SEQUENCE {
type AttributeType,
value AttributeValue }
+
This section defines the RECOMMENDED algorithm for converting a
distinguished name from an ASN.1 structured representation to an UTF-8
[RFC3629] encoded Unicode [Unicode] character string representation.
implementations.
+
2.1. Converting the RDNSequence
+
Zeilenga LDAP: Distinguished Names [Page 3]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-dn-13.txt 15 Febrary 2004
+INTERNET-DRAFT draft-ietf-ldapbis-dn-15.txt 24 October 2004
+
If the RDNSequence is an empty sequence, the result is the empty or
zero length string.
+
Otherwise, the output consists of the string encodings of each
RelativeDistinguishedName in the RDNSequence (according to Section
2.2), starting with the last element of the sequence and moving
backwards toward the first.
+
The encodings of adjoining RelativeDistinguishedNames are separated by
a comma (',' U+002C) character.
+
2.2. Converting RelativeDistinguishedName
+
When converting from an ASN.1 RelativeDistinguishedName to a string,
the output consists of the string encodings of each
AttributeTypeAndValue (according to Section 2.3), in any order.
+
Where there is a multi-valued RDN, the outputs from adjoining
AttributeTypeAndValues are separated by a plus sign ('+' U+002B)
character.
+
2.3. Converting AttributeTypeAndValue
+
The AttributeTypeAndValue is encoded as the string representation of
- the AttributeType, followed by an equals ('=' U+003D) character,
+ the AttributeType, followed by an equals sign ('=' U+003D) character,
followed by the string representation of the AttributeValue. The
encoding of the AttributeValue is given in Section 2.4.
+
If the AttributeType is defined to have a short name and that short
name is known to be registered [REGISTRY][BCP64bis] as identifying the
AttributeType, that short name, a <descr>, is used. Otherwise the
<numericoid>, of its OBJECT IDENTIFIER. The <descr> and <numericoid>
is defined in [Models].
+
Implementations are not expected to dynamically update their knowledge
of registered short names. However, implementations SHOULD provide a
mechanism to allow its knowledge of registered short names to be
updated.
+
2.4. Converting an AttributeValue from ASN.1 to a String
+
If the AttributeType is of the dotted-decimal form, the AttributeValue
is represented by an number sign ('#' U+0023) character followed by
the hexadecimal encoding of each of the octets of the BER encoding of
+
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+
the X.500 AttributeValue. This form is also used when the syntax of
form may also be used in other cases, such as when a reversible string
representation is desired (see Section 5.2).
+
Otherwise, if the AttributeValue is of a syntax which has a
LDAP-specific string encoding, the value is converted first to a UTF-8
encoded Unicode string according to its syntax specification (see
escaping, then that string can be used as the string representation of
the value.
+
- a space (' ' U+0020) or number sign ('#' U+0023) occurring at
the beginning of the string;
+
- a space (' ' U+0020) character occurring at the end of the
string;
+
- one of the characters '"', '+', ',', ';', '<', '>', or '\'
(U+0022, U+002B, U+002C, U+003B, U+003C, U+003E, or U+005C
respectively);
+
- the null (U+0000) character.
+
Other characters may be escaped.
+
Each octet of the character to be escaped is replaced by a backslash
and two hex digits, which form a single octet in the code of the
character. Alternatively, if and only if the character to be escaped
is one of
+
' ', '"', '#', '+', ',', ';', '<', '=', '>', or '\'
(U+0020, U+0022, U+0023, U+002B, U+002C, U+003B,
U+003C, U+003D, U+003E, U+005C respectively)
+
it can be prefixed by a backslash ('\' U+0005C).
+
Examples of the escaping mechanism are shown in Section 4.
+
3. Parsing a String back to a Distinguished Name
+
The string representation of Distinguished Names is restricted to
UTF-8 [RFC3629] encoded Unicode [Unicode] characters. The structure
of this string representation is specified using the following
+
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-\f
-INTERNET-DRAFT draft-ietf-ldapbis-dn-13.txt 15 Febrary 2004
+INTERNET-DRAFT draft-ietf-ldapbis-dn-15.txt 24 October 2004
+
Augmented BNF [RFC2234] grammar:
+
distinguishedName = [ relativeDistinguishedName
*( COMMA relativeDistinguishedName ) ]
relativeDistinguishedName = attributeTypeAndValue
attributeType = descr / numericoid
attributeValue = string / hexstring
+
; The following characters are to be escaped when they appear
; in the value to be encoded: ESC, one of <escaped>, leading
; SHARP or SPACE, trailing SPACE, and NULL.
- string = [ (leadchar / pair)
- [ *( stringchar / pair ) ( trailchar / pair ) ] ]
+ string = [ ( leadchar / pair ) [ *( stringchar / pair )
+ ( trailchar / pair ) ] ]
+
+
+ leadchar = LUTF1 / UTFMB
+ LUTF1 = %x01-1F / %x21 / %x24-2A / %x2D-3A /
+ %x3D / %x3F-5B / %x5D-7F
- leadchar = LUTF1 / UTFMB
- LUTF1 = %x01-1F / %x21 / %x24-2A / %x2D-3A /
- %x3D / %x3F-5B / %x5D-7F
trailchar = TUTF1 / UTFMB
- TUTF1 = %x01-1F / %x21 / %x23-2A / %x2D-3A /
- %x3D / %x3F-5B / %x5D-7F
+ TUTF1 = %x01-1F / %x21 / %x23-2A / %x2D-3A /
+ %x3D / %x3F-5B / %x5D-7F
+
stringchar = SUTF1 / UTFMB
- SUTF1 = %x01-21 / %x23-2A / %x2D-3A /
- %x3D / %x3F-5B / %x5D-7F
+ SUTF1 = %x01-21 / %x23-2A / %x2D-3A /
+ %x3D / %x3F-5B / %x5D-7F
+
+
+ pair = ESC ( ESC / special / hexpair )
+ special = escaped / SPACE / SHARP / EQUALS
+ escaped = DQUOTE / PLUS / COMMA / SEMI / LANGLE / RANGLE
+ hexstring = SHARP 1*hexpair
+ hexpair = HEX HEX
- pair = ESC ( ESC / special / hexpair )
- special = escaped / SPACE / SHARP / EQUALS
- escaped = DQUOTE / PLUS / COMMA / SEMI / LANGLE / RANGLE
- hexstring = SHARP 1*hexpair
- hexpair = HEX HEX
where the productions <descr>, <numericoid>, <COMMA>, <DQUOTE>,
<EQUALS>, <ESC>, <HEX>, <LANGLE>, <NULL>, <PLUS>, <RANGLE>, <SEMI>,
<SPACE>, <SHARP>, <UTFMB> are defined in [Models].
+
Each <attributeType>, either a <descr> or a <numericoid>, refers to an
attribute type of an attribute value assertion (AVA). The
<attributeType> is followed by a <EQUALS> and an <attributeValue>.
The <attributeValue> is either in <string> or <hexstring> form.
+
If in <string> form, a LDAP string representation asserted value can
be obtained by replacing (left-to-right, non-recursively) each <pair>
appearing in the <string> as follows:
+
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+INTERNET-DRAFT draft-ietf-ldapbis-dn-15.txt 24 October 2004
+
replace <ESC><hexpair> with the octet indicated by the <hexpair>.
+
If in <hexstring> form, a BER representation can be obtained from
converting each <hexpair> of the <hexstring> to the octet indicated by
the <hexpair>.
+
One or more attribute values assertions, separated by <PLUS>, for a
relative distinguished name.
+
Zero or more relative distinguished names, separated by <COMMA>, for a
distinguished name.
+
Implementations MUST recognize AttributeType name strings
(descriptors) listed in the following table, but MAY recognize other
name strings.
+
String X.500 AttributeType
------ --------------------------------------------
CN commonName (2.5.4.3)
DC domainComponent (0.9.2342.19200300.100.1.25)
UID userId (0.9.2342.19200300.100.1.1)
+
Implementations MAY recognize other DN string representations (such as
that described in RFC 1779). However, as there is no requirement that
alternative DN string representations to be recognized (and, if so,
with Section 2 of this document.
+
4. Examples
+
This notation is designed to be convenient for common forms of name.
This section gives a few examples of distinguished names written using
this notation. First is a name containing three relative
distinguished names (RDNs):
+
UID=jsmith,DC=example,DC=net
+
Here is an example name containing three RDNs, in which the first RDN
is multi-valued:
+
OU=Sales+CN=J. Smith,DC=example,DC=net
+
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-INTERNET-DRAFT draft-ietf-ldapbis-dn-13.txt 15 Febrary 2004
+INTERNET-DRAFT draft-ietf-ldapbis-dn-15.txt 24 October 2004
+
+
+
+ This example shows the method of escaping of a special characters
+ appearing in a common name:
+
+ CN=James \"Jim\" Smith\, III,DC=example,DC=net
- This example shows the method of escaping of a comma in a common name:
- CN=John Smith\, III,DC=example,DC=net
+ The following shows the method for encoding a value which contains a
+ carriage return character:
- An example name in which a value contains a carriage return character:
CN=Before\0dAfter,DC=example,DC=net
- An example name in which an RDN was of an unrecognized type. The
+
+ In this RDN example, the type in the RDN is unrecognized, and the
value is the BER encoding of an OCTET STRING containing two octets
0x48 and 0x69.
- 1.3.6.1.4.1.1466.0=#04024869,DC=example,DC=com
- Finally, an example of an RDN commonName value consisting of 5
- letters:
+ 1.3.6.1.4.1.1466.0=#04024869
+
+
+ Finally, this example shows an RDN whose commonName value consisting
+ of 5 letters:
+
Unicode Character Code UTF-8 Escaped
------------------------------- ------ ------ --------
LATIN SMALL LETTER I U+0069 0x69 i
LATIN SMALL LETTER C WITH ACUTE U+0107 0xC487 \C4\87
- could be written in printable ASCII (useful for debugging purposes):
+
+ could be encoded in printable ASCII (useful for debugging purposes)
+ as:
+
CN=Lu\C4\8Di\C4\87
+
5. Security Considerations
+
The following security considerations are specific to the handling of
distinguished names. LDAP security considerations are discussed in
[Protocol] and other documents comprising the LDAP Technical
Specification [Roadmap].
+
5.1. Disclosure
+
Distinguished Names typically consist of descriptive information about
the entries they name, which can be people, organizations, devices or
other real-world objects. This frequently includes some of the
following kinds of information:
- - the common name of the object (i.e. a person's full name)
- - an email or TCP/IP address
- - its physical location (country, locality, city, street address)
+
Zeilenga LDAP: Distinguished Names [Page 8]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-dn-13.txt 15 Febrary 2004
+INTERNET-DRAFT draft-ietf-ldapbis-dn-15.txt 24 October 2004
+
+ - the common name of the object (i.e. a person's full name)
+ - an email or TCP/IP address
+ - its physical location (country, locality, city, street address)
- organizational attributes (such as department name or affiliation)
+
Most countries have privacy laws regarding the publication of
information about people.
+
5.2. Use of Distinguished Names in Security Applications
+
The transformations of an AttributeValue value from its X.501 form to
an LDAP string representation are not always reversible back to the
same BER (Basic Encoding Rules) or DER (Distinguished Encoding rules)
form. An example of a situation which requires the DER form of a
distinguished name is the verification of an X.509 certificate.
+
For example, a distinguished name consisting of one RDN with one AVA,
in which the type is commonName and the value is of the TeletexString
choice with the letters 'Sam' would be represented in LDAP as the
still 'Sam' but of the PrintableString choice would have the same
representation <CN=Sam>.
+
Applications which require the reconstruction of the DER form of the
value SHOULD NOT use the string representation of attribute syntaxes
when converting a distinguished name to the LDAP format. Instead,
- they SHOULD use the hexadecimal form prefixed by the number sign ('#')
- as described in the first paragraph of Section 2.3.
+ they SHOULD use the hexadecimal form prefixed by the number sign ('#'
+ U+0023) as described in the first paragraph of Section 2.4.
+
6. Acknowledgment
+
This document is an update to RFC 2253, by Mark Wahl, Tim Howes, and
Steve Kille. RFC 2253 was a product of the IETF ASID Working Group.
+
This document is a product of the IETF LDAPBIS Working Group.
+
7. Document Editor's Address
+
Kurt D. Zeilenga
OpenLDAP Foundation
<Kurt@OpenLDAP.org>
-8. Normative References
- [X.501] International Telecommunication Union -
- Telecommunication Standardization Sector, "The Directory
- -- Models," X.501(1993) (also ISO/IEC 9594-2:1994).
+8. References
+
+
Zeilenga LDAP: Distinguished Names [Page 9]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-dn-13.txt 15 Febrary 2004
+INTERNET-DRAFT draft-ietf-ldapbis-dn-15.txt 24 October 2004
+
+
+
+ [[Note to the RFC Editor: please replace the citation tags used in
+ referencing Internet-Drafts with tags of the form RFCnnnn.]]
+
+
+
+8.1. Normative References
+
+
+ [X.501] International Telecommunication Union -
+ Telecommunication Standardization Sector, "The Directory
+ -- Models," X.501(1993) (also ISO/IEC 9594-2:1994).
[X.680] International Telecommunication Union -
Syntax Notation One (ASN.1) - Specification of Basic
Notation", X.680(1997) (also ISO/IEC 8824-1:1998).
+
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14 (also RFC 2119), March 1997.
+
[RFC2234] Crocker, D. and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", RFC 2234, November 1997.
- [RFC3329] Yergeau, F., "UTF-8, a transformation format of ISO
- 10646", RFC 3329 (also STD 64), November 2003.
+
+ [RFC3629] Yergeau, F., "UTF-8, a transformation format of ISO
+ 10646", RFC 3629 (also STD 63), November 2003.
+
[Unicode] The Unicode Consortium, "The Unicode Standard, Version
3.2.0" is defined by "The Unicode Standard, Version 3.0"
"Unicode Standard Annex #28: Unicode 3.2"
(http://www.unicode.org/reports/tr28/).
+
[Models] Zeilenga, K. (editor), "LDAP: Directory Information
Models", draft-ietf-ldapbis-models-xx.txt, a work in
progress.
+
[Roadmap] Zeilenga, K. (editor), "LDAP: Technical Specification
Road Map", draft-ietf-ldapbis-roadmap-xx.txt, a work in
progress.
+
[Protocol] Sermersheim, J. (editor), "LDAP: The Protocol",
draft-ietf-ldapbis-protocol-xx.txt, a work in progress.
+
[Syntaxes] Legg, S. (editor), "LDAP: Syntaxes and Matching Rules",
draft-ietf-ldapbis-syntaxes-xx.txt, a work in progress.
+
[Schema] Dally, K. (editor), "LDAP: User Schema",
draft-ietf-ldapbis-user-schema-xx.txt, a work in
+
+
+
+
+Zeilenga LDAP: Distinguished Names [Page 10]
+INTERNET-DRAFT draft-ietf-ldapbis-dn-15.txt 24 October 2004
+
+
+
progress.
+
[REGISTRY] IANA, Object Identifier Descriptors Registry,
<http://www.iana.org/...>.
-9. Informative References
-
- [ASCII] Coded Character Set--7-bit American Standard Code for
- Information Interchange, ANSI X3.4-1986.
+8.2. Informative References
-
-Zeilenga LDAP: Distinguished Names [Page 10]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-dn-13.txt 15 Febrary 2004
+ [ASCII] Coded Character Set--7-bit American Standard Code for
+ Information Interchange, ANSI X3.4-1986.
[X.500] International Telecommunication Union -
-- Overview of concepts, models and services,"
X.500(1993) (also ISO/IEC 9594-1:1994).
+
[X.690] International Telecommunication Union -
Telecommunication Standardization Sector, "Specification
of ASN.1 encoding rules: Basic Encoding Rules (BER),
Encoding Rules (DER)", X.690(1997) (also ISO/IEC
8825-1:1998).
+
[RFC2849] Good, G., "The LDAP Data Interchange Format (LDIF) -
Technical Specification", RFC 2849, June 2000.
- [BCP64bis] Zeilenga, K., "IANA Considerations for LDAP", draft-
- ietf-ldapbis-bcp64-xx.txt, a work in progress.
+
+ [BCP64bis] Zeilenga, K., "IANA Considerations for LDAP",
+ draft-ietf-ldapbis-bcp64-xx.txt, a work in progress.
+
[CharModel] Whistler, K. and M. Davis, "Unicode Technical Report
#17, Character Encoding Model", UTR17,
<http://www.unicode.org/unicode/reports/tr17/>, August
2000.
+
[Glossary] The Unicode Consortium, "Unicode Glossary",
<http://www.unicode.org/glossary/>.
+
Appendix A. Presentation Issues
+
This appendix is provided for informational purposes only, it is not a
normative part of this specification.
+
The string representation described in this document is not intended
to be presented to humans without translation. However, at times it
may be desirable to present non-translated DN strings to users. This
section discusses presentation issues associated with non-translated
DN strings. Presentation of translated DN strings issues are not
+
+
+
+
+Zeilenga LDAP: Distinguished Names [Page 11]
+INTERNET-DRAFT draft-ietf-ldapbis-dn-15.txt 24 October 2004
+
+
+
discussed in this appendix. Transcoding issues are also not discussed
in this appendix.
+
This appendix provides guidance for applications presenting DN strings
to users. This section is not comprehensive, it does not discuss all
presentation issues which implementors may face.
+
Not all user interfaces are capable of displaying the full set of
Unicode characters. Some Unicode characters are not displayable.
-
-
-Zeilenga LDAP: Distinguished Names [Page 11]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-dn-13.txt 15 Febrary 2004
-
-
It is recommended that human interfaces use the optional hex pair
escaping mechanism (Section 2.3) to produce a string representation
suitable for display to the user. For example, an application can
characters appearing in the AttributeValue's string representation (as
demonstrated in the final example of Section 4).
+
When a DN string is displayed in free form text, it is often necessary
to distinguish the DN string from surrounding text. While this is
often done with white space (as demonstrated in Section 4), it is
be noted to the user that the wrapping '<' and '>' characters are not
part of the DN string.
+
DN strings can be quite long. It is often desirable to line-wrap
overly long DN strings in presentations. Line wrapping should be done
by inserting white space after the RDN separator character or, if
the user that the inserted white space is not part of the DN string
and is to be removed before use in LDAP. For example,
+
The following DN string is long:
CN=Kurt D. Zeilenga,OU=Engineering,L=Redwood Shores,
O=OpenLDAP Foundation,ST=California,C=US
so it has been line-wrapped for readability. The extra white
space is to be removed before the DN string is used in LDAP.
+
It is not advised to insert white space otherwise as it may not be
obvious to the user which white space is part of the DN string and
which white space was added for readability.
+
Another alternative is to use the LDAP Data Interchange Format (LDIF)
+
+
+
+
+Zeilenga LDAP: Distinguished Names [Page 12]
+INTERNET-DRAFT draft-ietf-ldapbis-dn-15.txt 24 October 2004
+
+
+
[RFC2849]. For example,
+
# This entry has a long DN...
dn: CN=Kurt D. Zeilenga,OU=Engineering,L=Redwood Shores,
O=OpenLDAP Foundation,ST=California,C=US
-
-
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-\f
-INTERNET-DRAFT draft-ietf-ldapbis-dn-13.txt 15 Febrary 2004
-
-
Appendix B. Changes made since RFC 2253
+
This appendix is provided for informational purposes only, it is not a
normative part of this specification.
+
The following substantive changes were made to RFC 2253:
- Removed IESG Note. The IESG Note has been addressed.
- Replaced all references to ISO 10646-1 with [Unicode].
- Clarified (in Section 1) that this document does not define a
canonical string representation.
+ - Clarified that Section 2 describes the RECOMMENDED encoding
+ algorithm and that alternative algorithms are allowed. Some
+ encoding options described in RFC 2253 are now treated as
+ alternative algorithms in this specification.
- Revised specification (in Section 2) to allow short names of any
registered attribute type to appear in string representations of
DNs instead of being restricted to a "published table". Remove
recognition of additional names but require recognization of those
names in the published table. The table is now published in
Section 3.
- - Replaced specification of additional requirements for LDAPv2
- implementations which also support LDAPv3 (RFC 2253, Section 4)
- with a statement (in Section 3) allowing recognition of
- alternative string representations.
- - Updated Section 2.3 to indicate attribute type name strings are
- case insensitive.
+ - Removed specification of additional requirements for LDAPv2
+ implementations which also support LDAPv3 (RFC 2253, Section 4) as
+ LDAPv2 is now Historic.
+ - Allow recognition of alternative string representations.
- Updated Section 2.4 to allow hex pair escaping of all characters
- and clarified escaping for when multiple octet UTF-8 echodings are
- present.
+ and clarified escaping for when multiple octet UTF-8 encodings are
+ present. Indicated that null (U+0000) character is to be escaped.
+ Indicated that equals sign ('=' U+003D) character may be escaped
+ as '\='.
- Rewrote Section 3 to use ABNF as defined in RFC 2234.
- - Rewrote Section 3 ABNF to be consistent with 2.4.
+ - Updated the Section 3 ABNF. Changes include:
+ + allow AttributeType short names of length 1 (e.g., 'L'),
+ + use more restrictive <oid> production in AttributeTypes,
+ + do not require escaping of equals sign ('=' U+003D) characters,
+ + do not require escaping of non-leading number sign ('#' U+0023)
+ characters,
+ + allow space (' ' U+0020) to escaped as '\ ',
+
+
+
+
+Zeilenga LDAP: Distinguished Names [Page 13]
+INTERNET-DRAFT draft-ietf-ldapbis-dn-15.txt 24 October 2004
+
+
+
+ + require hex escaping of null (U+0000) characters, and
+ + removed LDAPv2-only constructs.
- Updated Section 3 to describe how to parse elements of the
grammar.
- Rewrote examples.
- Added discussion of presentation issues (Appendix A).
- Added this appendix.
+
In addition, numerous editorial changes were made.
-Intellectual Property Rights
- The IETF takes no position regarding the validity or scope of any
- intellectual property or other rights that might be claimed to pertain
- to the implementation or use of the technology described in this
- document or the extent to which any license under such rights might or
- might not be available; neither does it represent that it has made any
- effort to identify any such rights. Information on the IETF's
- procedures with respect to rights in standards-track and
+Intellectual Property Rights
+ The IETF takes no position regarding the validity or scope of any
+ Intellectual Property Rights or other rights that might be claimed to
+ pertain to the implementation or use of the technology described in
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+ might or might not be available; nor does it represent that it has
+ made any independent effort to identify any such rights. Information
+ on the procedures with respect to rights in RFC documents can be found
+ in BCP 78 and BCP 79.
-Zeilenga LDAP: Distinguished Names [Page 13]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-dn-13.txt 15 Febrary 2004
+ Copies of IPR disclosures made to the IETF Secretariat and any
+ assurances of licenses to be made available, or the result of an
+ attempt made to obtain a general license or permission for the use of
+ such proprietary rights by implementers or users of this specification
+ can be obtained from the IETF on-line IPR repository at
+ http://www.ietf.org/ipr.
- standards-related documentation can be found in BCP-11. Copies of
- claims of rights made available for publication and any assurances of
- licenses to be made available, or the result of an attempt made to
- obtain a general license or permission for the use of such proprietary
- rights by implementors or users of this specification can be obtained
- from the IETF Secretariat.
The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary
- rights which may cover technology that may be required to practice
- this standard. Please address the information to the IETF Executive
- Director.
+ rights that may cover technology that may be required to implement
+ this standard. Please address the information to the IETF at
+ ietf-ipr@ietf.org.
+
Full Copyright
- Copyright (C) The Internet Society (2004). All Rights Reserved.
- This document and translations of it may be copied and furnished to
- others, and derivative works that comment on or otherwise explain it
- or assist in its implementation may be prepared, copied, published and
- distributed, in whole or in part, without restriction of any kind,
- provided that the above copyright notice and this paragraph are
- included on all such copies and derivative works. However, this
- document itself may not be modified in any way, such as by removing
- the copyright notice or references to the Internet Society or other
- Internet organizations, except as needed for the purpose of
- developing Internet standards in which case the procedures for
- copyrights defined in the Internet Standards process must be followed,
- or as required to translate it into languages other than English.
+ Copyright (C) The Internet Society (2004). This document is subject
+ to the rights, licenses and restrictions contained in BCP 78, and
+ except as set forth therein, the authors retain all their rights.
+
+ This document and the information contained herein are provided on an
+ "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
+ OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
+Zeilenga LDAP: Distinguished Names [Page 14]
+INTERNET-DRAFT draft-ietf-ldapbis-dn-15.txt 24 October 2004
+ ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
+ INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
+ INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
+ WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
-Zeilenga LDAP: Distinguished Names [Page 14]
-\f
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+Zeilenga LDAP: Distinguished Names [Page 15]
\ No newline at end of file
+
Network Working Group M. Smith, Editor
Request for Comments: DRAFT Pearl Crescent, LLC
Obsoletes: RFC 2254 T. Howes
-Expires: 13 August 2004 Opsware, Inc.
- 13 February 2004
+Expires: 24 April 2005 Opsware, Inc.
+ 24 October 2004
LDAP: String Representation of Search Filters
- <draft-ietf-ldapbis-filter-06.txt>
+ <draft-ietf-ldapbis-filter-08.txt>
+
+Status of this Memo
-1. Status of this Memo
+ By submitting this Internet-Draft, each author represents that any
+ applicable patent or other IPR claims of which he or she is aware
+ have been or will be disclosed, and any of which he or she become
+ aware will be disclosed, in accordance with RFC 3668.
- This document is an Internet-Draft and is subject to all provisions
- of Section 10 of RFC2026.
+ This document is intended to be published as a Standards Track RFC,
+ replacing RFC 2254. Distribution of this memo is unlimited.
+ Technical discussion of this document will take place on the IETF
+ LDAP (v3) Revision (ldapbis) Working Group mailing list
+ <ietf-ldapbis@openldap.org>. Please send editorial comments directly
+ to the editor <mcs@pearlcrescent.com>.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that
- other groups may also distribute working documents as Internet-
- Drafts.
+ other groups may also distribute working documents as
+ Internet-Drafts.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
- time. It is inappropriate to use Internet- Drafts as reference
- material or to cite them other than as "work in progress."
+ time. It is inappropriate to use Internet-Drafts as reference
+ material or to cite them other than a "work in progress."
The list of current Internet-Drafts can be accessed at
http://www.ietf.org/1id-abstracts.html
The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html
- Discussion of this document should take place on the LDAP (v3)
- Revision (ldapbis) Working Group mailing list <ietf-
- ldapbis@openldap.org>.
-
Copyright (C) The Internet Society (2004). All Rights Reserved.
+ Please see the Full Copyright section near the end of this document
+ for more information.
-2. Abstract
-
- LDAP search filters are transmitted in the LDAP protocol using a
- binary representation that is appropriate for use on the network.
- This document defines a human-readable string representation of LDAP
- search filters that is appropriate for use in LDAP URLs and in other
- applications.
Smith & Howes Intended Category: Standards Track [Page 1]
\f
-INTERNET-DRAFT LDAP: String Repres. of Search Filters 13 February 2004
-
-
-3. Table of Contents
-
-1. Status of this Memo............................................1
-2. Abstract.......................................................1
-3. Table of Contents..............................................2
-4. Introduction...................................................2
-5. LDAP Search Filter Definition..................................2
-6. String Search Filter Definition................................4
-7. Examples.......................................................5
-8. Security Considerations........................................7
-9. Normative References...........................................7
-10. Informative References.........................................8
-11. Intellectual Property Rights...................................8
-12. Acknowledgments................................................8
-13. Authors' Addresses.............................................9
-14. Full Copyright Statement.......................................9
-15. Appendix A: Changes Since RFC 2254.............................10
-15.1. Technical Changes...........................................10
-15.2. Editorial Changes...........................................10
-16. Appendix B: Changes Since Previous Document Revision...........11
-16.1. Technical Changes...........................................12
-16.2. Editorial Changes...........................................12
-
-4. Introduction
+INTERNET-DRAFT LDAP: String Repres. of Search Filters 24 October 2004
+
+
+Abstract
+
+ LDAP search filters are transmitted in the LDAP protocol using a
+ binary representation that is appropriate for use on the network.
+ This document defines a human-readable string representation of LDAP
+ search filters that is appropriate for use in LDAP URLs and in other
+ applications.
+
+Table of Contents
+
+ Status of this Memo............................................1
+ Abstract.......................................................2
+ Table of Contents..............................................2
+1. Introduction...................................................2
+2. LDAP Search Filter Definition..................................3
+3. String Search Filter Definition................................4
+4. Examples.......................................................6
+5. Security Considerations........................................7
+6. IANA Considerations............................................7
+7. Normative References...........................................7
+8. Informative References.........................................8
+9. Acknowledgments................................................8
+10. Authors' Addresses.............................................8
+11. Appendix A: Changes Since RFC 2254.............................9
+11.1. Technical Changes...........................................9
+11.2. Editorial Changes...........................................10
+12. Appendix B: Changes Since Previous Document Revision...........11
+12.1. Editorial Changes...........................................11
+13. Intellectual Property Rights...................................11
+14. Full Copyright.................................................12
+
+1. Introduction
The Lightweight Directory Access Protocol (LDAP) [Protocol] defines a
network representation of a search filter transmitted to an LDAP
possible LDAP version 3 search filters, including extended match
filters.
- This document is an integral part of the LDAP Technical
- Specification [Roadmap].
+ This document is an integral part of the LDAP Technical Specification
+ [Roadmap].
This document replaces RFC 2254. Changes to RFC 2254 are summarized
in Appendix A.
+
+
+
+Smith & Howes Intended Category: Standards Track [Page 2]
+\f
+INTERNET-DRAFT LDAP: String Repres. of Search Filters 24 October 2004
+
+
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in BCP 14 [RFC2119].
-5. LDAP Search Filter Definition
+2. LDAP Search Filter Definition
An LDAPv3 search filter is defined in Section 4.5.1 of [Protocol] as
follows:
-
-
-Smith & Howes Intended Category: Standards Track [Page 2]
-\f
-INTERNET-DRAFT LDAP: String Repres. of Search Filters 13 February 2004
-
-
Filter ::= CHOICE {
- and [0] SET SIZE (1..MAX) OF filter Filter,
- or [1] SET SIZE (1..MAX) OF filter Filter,
- not [2] Filter,
- equalityMatch [3] AttributeValueAssertion,
- substrings [4] SubstringFilter,
- greaterOrEqual [5] AttributeValueAssertion,
- lessOrEqual [6] AttributeValueAssertion,
- present [7] AttributeDescription,
- approxMatch [8] AttributeValueAssertion,
- extensibleMatch [9] MatchingRuleAssertion }
+ and [0] SET SIZE (1..MAX) OF filter Filter,
+ or [1] SET SIZE (1..MAX) OF filter Filter,
+ not [2] Filter,
+ equalityMatch [3] AttributeValueAssertion,
+ substrings [4] SubstringFilter,
+ greaterOrEqual [5] AttributeValueAssertion,
+ lessOrEqual [6] AttributeValueAssertion,
+ present [7] AttributeDescription,
+ approxMatch [8] AttributeValueAssertion,
+ extensibleMatch [9] MatchingRuleAssertion }
SubstringFilter ::= SEQUENCE {
- type AttributeDescription,
- -- initial and final can occur at most once
- substrings SEQUENCE SIZE (1..MAX) OF substring CHOICE {
- initial [0] AssertionValue,
- any [1] AssertionValue,
- final [2] AssertionValue } }
+ type AttributeDescription,
+ -- initial and final can occur at most once
+ substrings SEQUENCE SIZE (1..MAX) OF substring CHOICE {
+ initial [0] AssertionValue,
+ any [1] AssertionValue,
+ final [2] AssertionValue } }
AttributeValueAssertion ::= SEQUENCE {
- attributeDesc AttributeDescription,
- assertionValue AssertionValue }
+ attributeDesc AttributeDescription,
+ assertionValue AssertionValue }
MatchingRuleAssertion ::= SEQUENCE {
- matchingRule [1] MatchingRuleId OPTIONAL,
- type [2] AttributeDescription OPTIONAL,
- matchValue [3] AssertionValue,
- dnAttributes [4] BOOLEAN DEFAULT FALSE }
+ matchingRule [1] MatchingRuleId OPTIONAL,
+ type [2] AttributeDescription OPTIONAL,
+ matchValue [3] AssertionValue,
+ dnAttributes [4] BOOLEAN DEFAULT FALSE }
AttributeDescription ::= LDAPString
-
-- Constrained to <attributedescription>
- -- [Models]
+ -- Constrained to <attributedescription>
+ -- [Models]
AttributeValue ::= OCTET STRING
AssertionValue ::= OCTET STRING
- LDAPString ::= OCTET STRING -- UTF-8 encoded,
- -- [ISO10646] characters
-
- The AttributeDescription is a string representation of the attribute
- description and is defined in [Protocol]. The AttributeValue and
- AssertionValue OCTET STRING have the form defined in [Syntaxes]. The
- Filter is encoded for transmission over a network using the Basic
- Encoding Rules defined in [X.690], with simplifications described in
-
Smith & Howes Intended Category: Standards Track [Page 3]
\f
-INTERNET-DRAFT LDAP: String Repres. of Search Filters 13 February 2004
+INTERNET-DRAFT LDAP: String Repres. of Search Filters 24 October 2004
- [Protocol].
+ LDAPString ::= OCTET STRING -- UTF-8 encoded,
+ -- [Unicode] characters
-6. String Search Filter Definition
+ The AttributeDescription is a string representation of the attribute
+ description and is defined in [Protocol]. The AttributeValue and
+ AssertionValue OCTET STRING have the form defined in [Syntaxes]. The
+ Filter is encoded for transmission over a network using the Basic
+ Encoding Rules (BER) defined in [X.690], with simplifications
+ described in [Protocol].
+
+3. String Search Filter Definition
The string representation of an LDAP search filter is a string of
- UTF-8[RFC3629] encoded ISO 10646-1 characters that is defined by the
- following grammar, following the ABNF notation defined in [RFC2234].
- The productions used that are not defined here are defined in section
- 1.4 (Common ABNF Productions) of [Models] unless otherwise noted.
- The filter format uses a prefix notation.
+ UTF-8 [RFC3629] encoded Unicode characters [Unicode] that is defined
+ by the following grammar, following the ABNF notation defined in
+ [RFC2234]. The productions used that are not defined here are
+ defined in section 1.4 (Common ABNF Productions) of [Models] unless
+ otherwise noted. The filter format uses a prefix notation.
filter = LPAREN filtercomp RPAREN
filtercomp = and / or / not / item
filterlist = 1*filter
item = simple / present / substring / extensible
simple = attr filtertype assertionvalue
- filtertype = equal / approx / greater / less
+ filtertype = equal / approx / greaterorequal / lessorequal
equal = EQUALS
approx = TILDE EQUALS
- greater = RANGLE EQUALS
- less = LANGLE EQUALS
- extensible = attr [dnattrs] [matchingrule] COLON EQUALS assertionvalue
- / [dnattrs] matchingrule COLON EQUALS assertionvalue
+ greaterorequal = RANGLE EQUALS
+ lessorequal = LANGLE EQUALS
+ extensible = attr [dnattrs]
+ [matchingrule] COLON EQUALS assertionvalue
+ / [dnattrs]
+ matchingrule COLON EQUALS assertionvalue
/ COLON EQUALS assertionvalue
present = attr EQUALS ASTERISK
substring = attr EQUALS [initial] any [final]
dnattrs = COLON "dn"
matchingrule = COLON oid
assertionvalue = valueencoding
- ; The <valueencoding> rule is used to encode an
- ; <AssertionValue> from Section 4.1.6 of [Protocol].
+
+
+
+Smith & Howes Intended Category: Standards Track [Page 4]
+\f
+INTERNET-DRAFT LDAP: String Repres. of Search Filters 24 October 2004
+
+
+ ; The <valueencoding> rule is used to encode an <AssertionValue>
+ ; from Section 4.1.6 of [Protocol].
valueencoding = 0*(normal / escaped)
normal = UTF1SUBSET / UTFMB
escaped = ESC HEX HEX
; RPAREN, ASTERISK, and ESC.
EXCLAMATION = %x21 ; exclamation mark ("!")
AMPERSAND = %x26 ; ampersand (or AND symbol) ("&")
-
-
-
-Smith & Howes Intended Category: Standards Track [Page 4]
-\f
-INTERNET-DRAFT LDAP: String Repres. of Search Filters 13 February 2004
-
-
ASTERISK = %x2A ; asterisk ("*")
COLON = %x3A ; colon (":")
VERTBAR = %x7C ; vertical bar (or pipe) ("|")
are not valid UTF-8 strings. This is necessary because RFC 2254 did
not clearly define the term "string representation" (and in
particular did not mention that the string representation of an LDAP
- search filter is a string of UTF-8 encoded ISO 10646-1 characters).
-7. Examples
- This section gives a few examples of search filters written using
- this notation.
- (cn=Babs Jensen)
- (!(cn=Tim Howes))
- (&(objectClass=Person)(|(sn=Jensen)(cn=Babs J*)))
+Smith & Howes Intended Category: Standards Track [Page 5]
+\f
+INTERNET-DRAFT LDAP: String Repres. of Search Filters 24 October 2004
+ search filter is a string of UTF-8 encoded Unicode characters).
-Smith & Howes Intended Category: Standards Track [Page 5]
-\f
-INTERNET-DRAFT LDAP: String Repres. of Search Filters 13 February 2004
+4. Examples
+ This section gives a few examples of search filters written using
+ this notation.
+ (cn=Babs Jensen)
+ (!(cn=Tim Howes))
+ (&(objectClass=Person)(|(sn=Jensen)(cn=Babs J*)))
(o=univ*of*mich*)
(seeAlso=)
The following examples illustrate the use of the escaping mechanism.
(o=Parens R Us \28for all your parenthetical needs\29)
+
+
+
+Smith & Howes Intended Category: Standards Track [Page 6]
+\f
+INTERNET-DRAFT LDAP: String Repres. of Search Filters 24 October 2004
+
+
(cn=*\2A*)
(filename=C:\5cMyFile)
(bin=\00\00\00\04)
represent parenthesis characters. The second shows how to represent a
"*" in an assertion value, preventing it from being interpreted as a
substring indicator. The third illustrates the escaping of the
-
-
-
-Smith & Howes Intended Category: Standards Track [Page 6]
-\f
-INTERNET-DRAFT LDAP: String Repres. of Search Filters 13 February 2004
-
-
backslash character.
The fourth example shows a filter searching for the four-byte value
The sixth and final example demonstrates assertion of a BER encoded
value.
-8. Security Considerations
+5. Security Considerations
This memo describes a string representation of LDAP search filters.
While the representation itself has no known security implications,
Please refer to the Security Considerations sections of [Protocol]
and [AuthMeth] for more information.
-9. Normative References
+6. IANA Considerations
-[AuthMeth] Harrison, R. (editor), "LDAP: Authentication Methods and
- Connection Level Security Mechanisms", draft-ietf-ldapbis-
- authmeth-xx.txt, a work in progress.
+ This document has no actions for IANA.
-[ISO10646] Universal Multiple-Octet Coded Character Set (UCS) -
- Architecture and Basic Multilingual Plane, ISO/IEC 10646-1,
- 1993.
+7. Normative References
+
+[AuthMeth] Harrison, R. (editor), "LDAP: Authentication Methods and
+ Connection Level Security Mechanisms",
+ draft-ietf-ldapbis-authmeth-xx.txt, a work in progress.
[Models] Zeilenga, K. (editor), "LDAP: Directory Information Models",
draft-ietf-ldapbis-models-xx.txt, a work in progress.
[Protocol] draft-ietf-ldapbis-protocol-xx.txt, a work in progress.
+
+
+
+Smith & Howes Intended Category: Standards Track [Page 7]
+\f
+INTERNET-DRAFT LDAP: String Repres. of Search Filters 24 October 2004
+
+
[RFC2119] S. Bradner, "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14 (also RFC 2119), March 1997.
[RFC3629] Yergeau, F., "UTF-8, a transformation format of ISO 10646",
RFC 3629, November 2003.
-
-
-
-
-Smith & Howes Intended Category: Standards Track [Page 7]
-\f
-INTERNET-DRAFT LDAP: String Repres. of Search Filters 13 February 2004
-
-
[Roadmap] Zeilenga, K. (editor), "LDAP: Technical Specification Road
Map", draft-ietf-ldapbis-roadmap-xx.txt, a work in progress.
-[Syntaxes] Dally, K. (editor), "LDAP: Syntaxes", draft-ietf-ldapbis-
- syntaxes-xx.txt, a work in progress.
+[Syntaxes] Dally, K. (editor), "LDAP: Syntaxes",
+ draft-ietf-ldapbis-syntaxes-xx.txt, a work in progress.
+
+[Unicode] The Unicode Consortium, "The Unicode Standard, Version
+ 3.2.0" is defined by "The Unicode Standard, Version 3.0"
+ (Reading, MA, Addison-Wesley, 2000. ISBN 0-201-61633-5), as
+ amended by the "Unicode Standard Annex #27: Unicode 3.1"
+ (http://www.unicode.org/reports/tr27/) and by the "Unicode
+ Standard Annex #28: Unicode 3.2."
[X.690] Specification of ASN.1 encoding rules: Basic, Canonical, and
Distinguished Encoding Rules, ITU-T Recommendation X.690,
1994.
-10. Informative References
+8. Informative References
None.
-11. Intellectual Property Rights
-
- The IETF takes no position regarding the validity or scope of any
- intellectual property or other rights that might be claimed to
- pertain to the implementation or use of the technology described in
- this document or the extent to which any license under such rights
- might or might not be available; neither does it represent that it
- has made any effort to identify any such rights. Information on the
- IETF's procedures with respect to rights in standards-track and
- standards-related documentation can be found in BCP-11. Copies of
- claims of rights made available for publication and any assurances of
- licenses to be made available, or the result of an attempt made to
- obtain a general license or permission for the use of such
- proprietary rights by implementors or users of this specification can
- be obtained from the IETF Secretariat.
-
- The IETF invites any interested party to bring to its attention any
- copyrights, patents or patent applications, or other proprietary
- rights which may cover technology that may be required to practice
- this standard. Please address the information to the IETF Executive
- Director.
-
-12. Acknowledgments
+9. Acknowledgments
This document replaces RFC 2254 by Tim Howes. Changes included in
this revised specification are based upon discussions among the
acknowledged.
+10. Authors' Addresses
-
+ Mark Smith, Editor
+ Pearl Crescent, LLC
+ 447 Marlpool Dr.
+ Saline, MI 48176
+ USA
+ +1 734 944-2856
Smith & Howes Intended Category: Standards Track [Page 8]
\f
-INTERNET-DRAFT LDAP: String Repres. of Search Filters 13 February 2004
-
+INTERNET-DRAFT LDAP: String Repres. of Search Filters 24 October 2004
-13. Authors' Addresses
- Mark Smith, Editor
- Pearl Crescent, LLC
- 447 Marlpool Dr.
- Saline, MI 48176
- USA
- +1 734 944-2856
mcs@pearlcrescent.com
+
Tim Howes
Opsware, Inc.
599 N. Mathilda Ave.
+1 408 744-7509
howes@opsware.com
-14. Full Copyright Statement
-
- Copyright (C) The Internet Society (2004). All Rights Reserved.
-
- This document and translations of it may be copied and furnished to
- others, and derivative works that comment on or otherwise explain it
- or assist in its implementation may be prepared, copied, published
- and distributed, in whole or in part, without restriction of any
- kind, provided that the above copyright notice and this paragraph are
- included on all such copies and derivative works. However, this
- document itself may not be modified in any way, such as by removing
- the copyright notice or references to the Internet Society or other
- Internet organizations, except as needed for the purpose of
- developing Internet standards in which case the procedures for
- copyrights defined in the Internet Standards process must be
- followed, or as required to translate it into languages other than
- English.
-
- The limited permissions granted above are perpetual and will not be
- revoked by the Internet Society or its successors or assigns.
-
- This document and the information contained herein is provided on an
- "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
- TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
- BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
- HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
- MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
-
-
-
-
-
-
-Smith & Howes Intended Category: Standards Track [Page 9]
-\f
-INTERNET-DRAFT LDAP: String Repres. of Search Filters 13 February 2004
-
+11. Appendix A: Changes Since RFC 2254
-15. Appendix A: Changes Since RFC 2254
+11.1. Technical Changes
-15.1. Technical Changes
+ Replaced [ISO 10646] reference with [Unicode].
The following technical changes were made to the contents of the
"String Search Filter Definition" section:
Added statement that the string representation is a string of UTF-8
- encoded ISO 10646-1 characters.
+ encoded Unicode characters.
Revised all of the ABNF to use common productions from [Models].
precisely reference productions from the [Models] and [Protocol]
documents.
+ "String Search Filter Definition" section: replaced "greater" and
+ "less" with "greaterorequal" and "lessorequal" to avoid confusion.
+
Introduced the "valueencoding" and associated "normal" and "escaped"
rules to reduce the dependence on descriptive text. The "normal"
production restricts filter strings to valid UTF-8 sequences.
of a clear definition of "string representation."
-15.2. Editorial Changes
+
+
+
+
+Smith & Howes Intended Category: Standards Track [Page 9]
+\f
+INTERNET-DRAFT LDAP: String Repres. of Search Filters 24 October 2004
+
+
+11.2. Editorial Changes
Changed document title to include "LDAP:" prefix.
Header and "Authors' Addresses" sections: added Mark Smith as the
document editor and updated affiliation and contact information.
- "Table of Contents" and "Intellectual Property Rights" sections:
- added.
+ "Table of Contents", "IANA Considerations", and "Intellectual
+ Property Rights" sections: added.
Copyright: updated per latest IETF guidelines.
"Abstract" section: separated from introductory material.
-
-
-
-Smith & Howes Intended Category: Standards Track [Page 10]
-\f
-INTERNET-DRAFT LDAP: String Repres. of Search Filters 13 February 2004
-
-
"Introduction" section: new section; separated from the Abstract.
Updated second paragraph to indicate that RFC 2254 is replaced by
this document (instead of RFC 1960). Added reference to the [Roadmap]
"Normative References" section: renamed from "References" per new RFC
guidelines. Changed from [1] style to [Protocol] style throughout the
- document. Added entries for [ISO10646], [RFC2119], [AuthMeth],
+ document. Added entries for [Unicode], [RFC2119], [AuthMeth],
[Models], and [Roadmap] and updated the UTF-8 reference. Replaced
RFC 822 reference with a reference to RFC 2234.
+
+
+
+
+Smith & Howes Intended Category: Standards Track [Page 10]
+\f
+INTERNET-DRAFT LDAP: String Repres. of Search Filters 24 October 2004
+
+
"Informative References" section: added for clarity.
"Acknowledgments" section: added.
added.
-16. Appendix B: Changes Since Previous Document Revision
+12. Appendix B: Changes Since Previous Document Revision
This appendix lists all changes relative to the previously published
- revision, draft-ietf-ldapbis-filter-05.txt. Note that when
+ revision, draft-ietf-ldapbis-filter-07.txt. Note that when
appropriate these changes are also included in Appendix A, but are
also included here for the benefit of the people who have already
- reviewed draft-ietf-ldapbis-filter-05.txt. This section will be
+ reviewed draft-ietf-ldapbis-filter-07.txt. This section will be
removed before this document is published as an RFC.
+12.1. Editorial Changes
+
+ "Status of this Memo" section: replaced RFC 3668 (IPR) boilerplate
+ paragraph with the version that says "each author" instead of "I."
+
+ "Status of this Memo" section: added 2 paragraphs that were
+ accidently removed from the -07 revision (one begins with "The list
+ of current Internet-Drafts..." and the other begins with "The list of
+ Internet-Draft Shadow Directories...."
+
+
+13. Intellectual Property Rights
+
+ The IETF takes no position regarding the validity or scope of any
+ Intellectual Property Rights or other rights that might be claimed to
+ pertain to the implementation or use of the technology described in
+ this document or the extent to which any license under such rights
+ might or might not be available; nor does it represent that it has
+ made any independent effort to identify any such rights. Information
+ on the procedures with respect to rights in RFC documents can be
+ found in BCP 78 and BCP 79.
+
+ Copies of IPR disclosures made to the IETF Secretariat and any
+ assurances of licenses to be made available, or the result of an
+ attempt made to obtain a general license or permission for the use of
+ such proprietary rights by implementers or users of this
+ specification can be obtained from the IETF on-line IPR repository at
+ http://www.ietf.org/ipr.
+
+
Smith & Howes Intended Category: Standards Track [Page 11]
\f
-INTERNET-DRAFT LDAP: String Repres. of Search Filters 13 February 2004
+INTERNET-DRAFT LDAP: String Repres. of Search Filters 24 October 2004
-16.1. Technical Changes
+ The IETF invites any interested party to bring to its attention any
+ copyrights, patents or patent applications, or other proprietary
+ rights that may cover technology that may be required to implement
+ this standard. Please address the information to the IETF at
+ ietf-ipr@ietf.org.
- None.
+14. Full Copyright
+
+ Copyright (C) The Internet Society (2004). This document is subject
+ to the rights, licenses and restrictions contained in BCP 78, and
+ except as set forth therein, the authors retain all their rights.
+
+ This document and the information contained herein are provided on an
+ "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
+ OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
+ ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
+ INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
+ INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
+ WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
+
+
+This Internet Draft expires on 24 April 2005.
-16.2. Editorial Changes
- "LDAP Search Filter Definition" section: changed the LDAPv3 search
- filter ABNF so it matches that used in the latest revision of
- [Protocol] and removed the following redundant descriptive text:
- "where the LDAPString above is limited to the UTF-8 encoding [UTF-8]
- of the ISO 10646 character set [ISO10646]."
- "String Search Filter Definition" section: Corrected section
- reference to [Models] and replaced this sentence: "Implementations
- SHOULD accept as input a string that includes invalid UTF-8 octet
- sequences." with the following: "Implementations SHOULD accept as
- input strings that are not valid UTF-8 strings."
- "Examples" section: Corrected the description of this example:
- (sn:dn:2.4.6.8.10:=Barney Rubble).
- "Normative References" section: changed UTF-8 reference to point to
- RFC 3629, replaced [ASN.1] with [X.690] for consistency, and indented
- the reference descriptions to enhance readability.
- Authors' Addresses section: New contact information for Mark Smith.
- Updated the copyright year to 2004.
-This Internet Draft expires on 13 August 2004.
-
-
-
-
-
-
INTERNET-DRAFT Editor: Kurt D. Zeilenga
Intended Category: Standard Track OpenLDAP Foundation
-Expires in six months 15 February 2004
+Expires in six months 24 October 2004
Obsoletes: RFC 2251, RFC 2252, RFC 2256
+
LDAP: Directory Information Models
- <draft-ietf-ldapbis-models-10.txt>
+ <draft-ietf-ldapbis-models-12.txt>
+
Status of this Memo
- This document is an Internet-Draft and is in full conformance with all
- provisions of Section 10 of RFC2026.
This document is intended to be published as a Standard Track RFC.
Distribution of this memo is unlimited. Technical discussion of this
mailing list <ietf-ldapbis@openldap.org>. Please send editorial
comments directly to the editor <Kurt@OpenLDAP.org>.
+
+ By submitting this Internet-Draft, I accept the provisions of Section
+ 4 of RFC 3667. By submitting this Internet-Draft, I certify that any
+ applicable patent or other IPR claims of which I am aware have been
+ disclosed, or will be disclosed, and any of which I become aware will
+ be disclosed, in accordance with RFC 3668.
+
+
Internet-Drafts are working documents of the Internet Engineering Task
- Force (IETF), its areas, and its working groups. Note that other
+ Force (IETF), its areas, and its working groups. Note that other
groups may also distribute working documents as Internet-Drafts.
+
+
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
- time. It is inappropriate to use Internet-Drafts as reference
- material or to cite them other than as ``work in progress.''
+ time. It is inappropriate to use Internet-Drafts as reference material
+ or to cite them other than as "work in progress."
+
The list of current Internet-Drafts can be accessed at
- <http://www.ietf.org/ietf/1id-abstracts.txt>. The list of
+ <http://www.ietf.org/ietf/1id-abstracts.txt>. The list of
Internet-Draft Shadow Directories can be accessed at
<http://www.ietf.org/shadow.html>.
+
Copyright (C) The Internet Society (2004). All Rights Reserved.
+
Please see the Full Copyright section near the end of this document
for more information.
+
+
+
+
+
+
+Zeilenga LDAP Models [Page 1]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
Abstract
+
The Lightweight Directory Access Protocol (LDAP) is an Internet
protocol for accessing distributed directory services which act in
accordance with X.500 data and service models. This document
describes the X.500 Directory Information Models, as used in LDAP.
-
-Zeilenga LDAP Models [Page 1]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
Table of Contents
+
Status of this Memo 1
- Abstract
- Table of Contents 2
+ Abstract 2
+ Table of Contents
1. Introduction 3
1.1. Relationship to Other LDAP Specifications
1.2. Relationship to X.501 4
1.4. Common ABNF Productions
2. Model of Directory User Information 6
2.1. The Directory Information Tree 7
- 2.2. Naming of Entries
- 2.3. Structure of an Entry 8
+ 2.2. Structure of an Entry
+ 2.3. Naming of Entries 8
2.4. Object Classes 9
- 2.5. Attribute Descriptions 11
+ 2.5. Attribute Descriptions 12
2.6. Alias Entries 15
3. Directory Administrative and Operational Information 17
3.1. Subtrees
3.2. Subentries
- 3.3. The 'objectClass' attribute
- 3.4. Operational attributes 18
- 4. Directory Schema 21
- 4.1. Schema Definitions 22
- 4.2. Subschema Subentries 31
+ 3.3. The 'objectClass' attribute 18
+ 3.4. Operational attributes 19
+ 4. Directory Schema 20
+ 4.1. Schema Definitions 23
+ 4.2. Subschema Subentries 30
4.3. 'extensibleObject' 35
4.4. Subschema Discovery
- 5. DSA (Server) Informational Model
- 5.1. Server-specific Data Requirements 36
+ 5. DSA (Server) Informational Model 36
+ 5.1. Server-specific Data Requirements
6. Other Considerations 39
- 6.1. Preservation of User Information
- 6.2. Short Names 40
- 6.3. Cache and Shadowing
+ 6.1. Preservation of User Information 40
+ 6.2. Short Names
+ 6.3. Cache and Shadowing 41
7. Implementation Guidelines
7.1. Server Guidelines
- 7.2. Client Guidelines 41
- 8. Security Considerations
- 9. IANA Considerations 42
+ 7.2. Client Guidelines
+ 8. Security Considerations 42
+ 9. IANA Considerations
10. Acknowledgments 43
11. Editor's Address
- 12. References
- 12.1. Normative References
- 12.2. Informative References 45
- Appendix A. Changes
- Intellectual Property Rights 49
- Full Copyright
-
+ 12. References 44
Zeilenga LDAP Models [Page 2]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
+ 12.1. Normative References
+ 12.2. Informative References 45
+ Appendix A. Changes
+ Intellectual Property Rights 50
+ Full Copyright
+
1. Introduction
+
This document discusses the X.500 Directory Information Models
[X.501], as used by the Lightweight Directory Access Protocol (LDAP)
[Roadmap].
+
The Directory is "a collection of open systems cooperating to provide
directory services" [X.500]. The information held in the Directory is
collectively known as the Directory Information Base (DIB). A
servers (or Directory System Agents (DSA)). A server holds a fragment
of the DIB.
+
The DIB contains two classes of information:
+
1) user information (e.g., information provided and administrated
by users). Section 2 describes the Model of User Information.
+
2) administrative and operational information (e.g., information
used to administer and/or operate the directory). Section 3
describes the model of Directory Administrative and Operational
Information.
+
These two models, referred to as the generic Directory Information
Models, describe how information is represented in the Directory.
These generic models provide a framework for other information models.
Section 4 discusses the subschema information model and subschema
discovery. Section 5 discusses the DSA (Server) Informational Model.
+
Other X.500 information models, such as access control distribution
knowledge, and replication knowledge information models, may be
adapted for use in LDAP. Specification of how these models apply to
LDAP is left to future documents.
+
1.1. Relationship to Other LDAP Specifications
+
This document is a integral part of the LDAP technical specification
[Roadmap] which obsoletes the previously defined LDAP technical
+
+
+
+
+Zeilenga LDAP Models [Page 3]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
specification, RFC 3377, in its entirety.
+
This document obsoletes RFC 2251 sections 3.2 and 3.4, as well as
portions of sections 4 and 6. Appendix A.1 summaries changes to these
sections. The remainder of RFC 2251 is obsoleted by the [Protocol],
[AuthMeth], and [Roadmap] documents.
-
-
-Zeilenga LDAP Models [Page 3]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
This document obsoletes RFC 2252 sections 4, 5 and 7. Appendix A.2
summaries changes to these sections. The remainder of RFC 2252 is
obsoleted by [Syntaxes].
+
This document obsoletes RFC 2256 sections 5.1, 5.2, 7.1 and 7.2.
Appendix A.3 summarizes changes to these sections. The remainder of
RFC 2256 is obsoleted by [Schema] and [Syntaxes].
+
1.2. Relationship to X.501
+
This document includes material, with and without adaptation, from
[X.501]. The material in this document takes precedence over that in
[X.501].
+
1.3. Conventions
+
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in BCP 14 [RFC2119].
+
Schema definitions are provided using LDAP description formats (as
defined in Section 4.1). Definitions provided here are formatted
(line wrapped) for readability. Matching rules and LDAP syntaxes
referenced in these definitions are specified in [Syntaxes].
+
1.4. Common ABNF Productions
+
A number of syntaxes in this document are described using Augmented
Backus-Naur Form (ABNF) [RFC2234]. These syntaxes (as well as a
number of syntaxes defined in other documents) rely on the following
common productions:
+
keystring = leadkeychar *keychar
leadkeychar = ALPHA
keychar = ALPHA / DIGIT / HYPHEN
number = DIGIT / ( LDIGIT 1*DIGIT )
- ALPHA = UALPHA / %x61-7A ; "A"-"Z" / "a"-"z"
- UALPHA = %x41-5A ; "A"-"Z"
+
+ ALPHA = %x41-5A / %x61-7A ; "A"-"Z" / "a"-"z"
+
+
+
+
+Zeilenga LDAP Models [Page 4]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
DIGIT = %x30 / LDIGIT ; "0"-"9"
LDIGIT = %x31-39 ; "1"-"9"
HEX = DIGIT / %x41-46 / %x61-66 ; "0"-"9" / "A"-"F" / "a"-"f"
+
SP = 1*SPACE ; one or more " "
WSP = 0*SPACE ; zero or more " "
-
-Zeilenga LDAP Models [Page 4]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
NULL = %x00 ; null (0)
SPACE = %x20 ; space (" ")
DQUOTE = %x22 ; quote (""")
LCURLY = %x7B ; left curly brace "{"
RCURLY = %x7D ; right curly brace "}"
- ; Any UTF-8 [UTF-8] encoded UCS [ISO10646] character
+
+ ; Any UTF-8 [UTF-8] encoded Unicode [Unicode] character
UTF8 = UTF1 / UTFMB
UTFMB = UTF2 / UTF3 / UTF4
UTF0 = %x80-BF
UTF4 = %xF0 %x90-BF 2(UTF0) / %xF1-F3 3(UTF0) /
%xF4 %x80-8F 2(UTF0)
- OCTET = %x00-FF ; Any octet
- Object identifiers (OIDs) [X.680] are represented in LDAP using a dot-
- decimal format conforming to the ABNF:
+ OCTET = %x00-FF ; Any octet (8-bit data unit)
+
+
+ Object identifiers (OIDs) [X.680] are represented in LDAP using a
+ dot-decimal format conforming to the ABNF:
+
numericoid = number 1*( DOT number )
+
Short names, also known as descriptors, are used as more readable
aliases for object identifiers. Short names are case insensitive and
- conform to the ABNF:
- descr = keystring
- Where either an object identifier or a short name may be specified,
- the following production is used:
+Zeilenga LDAP Models [Page 5]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
-Zeilenga LDAP Models [Page 5]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
+
+ conform to the ABNF:
+
+
+ descr = keystring
+
+
+ Where either an object identifier or a short name may be specified,
+ the following production is used:
oid = descr / numericoid
+
While the <descr> form is generally preferred when the usage is
restricted to short names referring to object identifiers which
identify like kinds of objects (e.g., attribute type descriptions,
identify multiple kinds of objects or when an unambiguous short name
(descriptor) is not available.
+
Implementations SHOULD treat short names (descriptors) used in an
- unambiguous manner (as discussed above) as unrecognized.
+ ambiguous manner (as discussed above) as unrecognized.
+
Short Names (descriptors) are discussed further in Section 6.2.
+
2. Model of Directory User Information
+
As [X.501] states:
+
The purpose of the Directory is to hold, and provide access to,
information about objects of interest (objects) in some 'world'.
An object can be anything which is identifiable (can be named).
+
An object class is an identified family of objects, or conceivable
objects, which share certain characteristics. Every object belongs
to at least one class. An object class may be a subclass of other
the superclasses. There may be subclasses of subclasses, etc., to
an arbitrary depth.
+
A directory entry, a named collection of information, is the basic
unit of information held in the Directory. There are multiple kinds
of directory entries.
+
An object entry represents a particular object. An alias entry
provides alternative naming. A subentry holds administrative and/or
operational information.
+
The set of entries representing the DIB are organized hierarchically
- in a tree structure known as the Directory Information Tree (DIT).
- Section 2.1 describes the Directory Information Tree
- Section 2.2 discusses naming of entries.
- Section 2.3 discusses the structure of entries.
- Section 2.4 discusses object classes.
- Section 2.5 discusses attribute descriptions.
Zeilenga LDAP Models [Page 6]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+ in a tree structure known as the Directory Information Tree (DIT).
+
+
+ Section 2.1 describes the Directory Information Tree
+ Section 2.2 discusses the structure of entries.
+ Section 2.3 discusses naming of entries.
+ Section 2.4 discusses object classes.
+ Section 2.5 discusses attribute descriptions.
Section 2.6 discusses alias entries.
+
2.1. The Directory Information Tree
+
As noted above, the DIB is composed of a set of entries organized
hierarchically in a tree structure known as the Directory Information
Tree (DIT). Specifically, a tree where vertices are the entries.
+
The arcs between vertices define relations between entries. If an arc
exists from X to Y, then the entry at X is the immediate superior of Y
and Y is the immediate subordinate of X. An entry's superiors are the
entry's immediate superior and its superiors. An entry's subordinates
are all of its immediate subordinates and their subordinates.
+
Similarly, the superior/subordinate relationship between object
entries can be used to derive a relation between the objects they
represent. DIT structure rules can be used to govern relationships
between objects.
+
Note: An entry's immediate superior is also known as the entry's
parent and an entry's immediate subordinate is also known as the
entry's child. Entries which have the same parent are known as
siblings.
-2.2. Naming of Entries
-2.2.1. Relative Distinguished Names
+2.2. Structure of an Entry
+
+
+ An entry consists of a set of attributes which hold information about
+ the object which the entry represents. Some attributes represent user
+ information and are called user attributes. Other attributes
+ represent operational and/or administrative information and are called
+ operational attributes.
+
+
+ An attribute is an attribute description (a type and zero or more
+ options) with one or more associated values. An attribute is often
+ referred to by its attribute description. For example, the
+ 'givenName' attribute is the attribute which consists of the attribute
+ description 'givenName' (the 'givenName' attribute type [Schema] and
+ zero options) and one or more associated values.
+
+
+
+
+
+Zeilenga LDAP Models [Page 7]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
+ The attribute type governs whether the attribute can have multiple
+ values, the syntax and matching rules used to construct and compare
+ values of that attribute, and other functions. Options indicate
+ subtypes and other functions.
+
+
+ Attribute values conform to the defined syntax of the attribute type.
+
+
+ No two values of an attribute may be equivalent. Two values are
+ considered equivalent only if they would match according to the
+ equality matching rule of the attribute type. If the attribute type
+ is defined with no equality matching rule, two values are equivalent
+ if and only if they are identical. (See 2.5.1 for other
+ restrictions.)
+
+
+ For example, a 'givenName' attribute can have more than one value,
+ they must be Directory Strings, and they are case insensitive. A
+ 'givenName' attribute cannot hold both "John" and "JOHN" as these are
+ equivalent values per the equality matching rule of the attribute
+ type.
+
+
+ When an attribute is used for naming of the entry, one and only one
+ value of the attribute is used in forming the Relative Distinguished
+ Name. This value is known as a distinguished value.
+
+
+
+2.3. Naming of Entries
+
+
+2.3.1. Relative Distinguished Names
+
Each entry is named relative to its immediate superior. This relative
name, known as its Relative Distinguished Name (RDN) [X.501], is
composed of an unordered set of one or more attribute value assertions
(AVA) consisting of an attribute description with zero options and an
- attribute value. These AVAs are chosen from the attributes of the
- entry.
+ attribute value. These AVAs are chosen to match attribute values
+ (each a distinguished value) of the entry.
+
An entry's relative distinguished name must be unique among all
immediate subordinates of the entry's immediate superior (i.e., all
siblings).
+
The following are examples of string representations of RDNs [LDAPDN]:
+
UID=12345
OU=Engineering
CN=Kurt Zeilenga+L=Redwood Shores
+
The last is an example of a multi-valued RDN. That is, an RDN
+ composed of multiple AVAs.
-Zeilenga LDAP Models [Page 7]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
+
+Zeilenga LDAP Models [Page 8]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
- composed of multiple AVAs.
+2.3.2. Distinguished Names
-2.2.2. Distinguished Names
An entry's fully qualified name, known as its Distinguished Name (DN)
[X.501], is the concatenation of its RDN and its immediate superior's
tree. The following are examples of string representations of DNs
[LDAPDN]:
+
UID=nobody@example.com,DC=example,DC=com
CN=John Smith,OU=Sales,O=ACME Limited,L=Moab,ST=Utah,C=US
-2.2.3. Alias Names
+
+2.3.3. Alias Names
+
An alias, or alias name, is "an name for an object, provided by the
use of alias entries" [X.501]. Alias entries are described in Section
2.6.
-2.3. Structure of an Entry
-
- An entry consists of a set of attributes which hold information about
- the object which the entry represents. Some attributes represent user
- information and are called user attributes. Other attributes
- represent operational and/or administrative information and are called
- operational attributes.
-
- An attribute is an attribute description (a type and zero or more
- options) with one or more associated values. An attribute is often
- referred to by its attribute description. For example, the
- 'givenName' attribute is the attribute which consists of the attribute
- description 'givenName' (the 'givenName' attribute type [Schema] and
- zero options) and one or more associated values.
-
- The attribute type governs whether the attribute can have multiple
- values, the syntax and matching rules used to construct and compare
- values of that attribute, and other functions. Options indicate
- subtypes and other functions. No two values of an attribute may be
- equivalent.
-
- Two values are considered equivalent if they would match according to
- the equality matching rule of the attribute type. If the attribute
- type is defined with no equality matching rule, two values are
- equivalent if and only if they are identical.
-
-
-
-
-Zeilenga LDAP Models [Page 8]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
- For example, a 'givenName' attribute can have can have more than one
- value, they must be Directory Strings, and they are case insensitive.
- A 'givenName' attribute cannot hold both "John" and "JOHN" as these
- are equivalent values per the equality matching rule of the attribute
- type.
-
2.4. Object Classes
+
An object class is "an identified family of objects (or conceivable
objects) which share certain characteristics" [X.501].
+
As defined in [X.501]:
+
Object classes are used in the Directory for a number of purposes:
+
- describing and categorising objects and the entries that
correspond to these objects;
+
- where appropriate, controlling the operation of the Directory;
+
- regulating, in conjunction with DIT structure rule
specifications, the position of entries in the DIT;
+
- regulating, in conjunction with DIT content rule
specifications, the attributes that are contained in entries;
+
- identifying classes of entry that are to be associated with a
particular policy by the appropriate administrative authority.
+
An object class (a subclass) may be derived from an object class
(its direct superclass) which is itself derived from an even more
generic object class. For structural object classes, this process
2.4.1). An ordered set of superclasses up to the most superior
object class of an object class is its superclass chain.
+
+
+
+Zeilenga LDAP Models [Page 9]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
An object class may be derived from two or more direct
superclasses (superclasses not part of the same superclass chain).
This feature of subclassing is termed multiple inheritance.
+
Each object class identifies the set of attributes required to be
present in entries belonging to the class and the set of attributes
allowed to be present in entries belonging to the class. As an entry
can be said that an object class inherits the sets of allowed and
required attributes from its superclasses. A subclass can identify an
attribute allowed by its superclass as being required. If an
-
-
-
-Zeilenga LDAP Models [Page 9]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
attribute is a member of both sets, it is required to be present.
+
Each object class is defined to be one of three kinds of object
classes: Abstract, Structural, or Auxiliary.
+
Each object class is identified by an object identifier (OID) and,
optionally, one or more short names (descriptors).
+
2.4.1. Abstract Object Classes
+
An abstract object class, as the name implies, provides a base of
characteristics from which other object classes can be defined to
inherit from. An entry cannot belong to an abstract object class
unless it belongs to a structural or auxiliary class which inherits
from that abstract class.
+
Abstract object classes can not derive from structural nor auxiliary
object classes.
+
All structural object classes derive (directly or indirectly) from the
'top' abstract object class. Auxiliary object classes do not
necessarily derive from 'top'.
+
The following is the object class definition (see Section 4.1.1) for
the 'top' object class:
+
( 2.5.6.0 NAME 'top' ABSTRACT MUST objectClass )
+
All entries belong to the 'top' abstract object class.
+
2.4.2. Structural Object Classes
+
As stated in [X.501]:
+
An object class defined for use in the structural specification of
+
+
+
+
+Zeilenga LDAP Models [Page 10]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
the DIT is termed a structural object class. Structural object
classes are used in the definition of the structure of the names
of the objects for compliant entries.
+
An object or alias entry is characterised by precisely one
structural object class superclass chain which has a single
structural object class as the most subordinate object class.
This structural object class is referred to as the structural
object class of the entry.
- Structural object classes are related to associated entries:
-
-
-Zeilenga LDAP Models [Page 10]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
+ Structural object classes are related to associated entries:
- an entry conforming to a structural object class shall
represent the real-world object constrained by the object
class;
+
- DIT structure rules only refer to structural object classes;
the structural object class of an entry is used to specify the
position of the entry in the DIT;
+
- the structural object class of an entry is used, along with an
associated DIT content rule, to control the content of an
entry.
+
The structural object class of an entry shall not be changed.
+
Each structural object class is a (direct or indirect) subclass of the
'top' abstract object class.
+
Structural object classes cannot subclass auxiliary object classes.
+
Each entry is said to belong to its structural object class as well as
all classes in its structural object class's superclass chain.
+
2.4.3. Auxiliary Object Classes
- Auxiliary object classes are used augment the characteristics of
+
+ Auxiliary object classes are used to augment the characteristics of
entries. They are commonly used to augment the sets of attributes
required and allowed to be present in an entry. They can be used to
describe entries or classes of entries.
+
Auxiliary object classes cannot subclass structural object classes.
+
An entry can belong to any subset of the set of auxiliary object
classes allowed by the DIT content rule associated with the structural
object class of the entry. If no DIT content rule is associated with
the structural object class of the entry, the entry cannot belong to
+
+
+
+
+Zeilenga LDAP Models [Page 11]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
any auxiliary object class.
+
The set of auxiliary object classes which an entry belongs to can
change over time.
+
2.5. Attribute Descriptions
+
An attribute description is composed of an attribute type (see Section
2.5.1) and a set of zero or more attribute options (see Section
2.5.2).
-
-
-Zeilenga LDAP Models [Page 11]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
An attribute description is represented by the ABNF:
+
attributedescription = attributetype options
attributetype = oid
options = *( SEMI option )
option = 1*keychar
+
where <attributetype> identifies the attribute type and each <option>
identifies an attribute option. Both <attributetype> and <option>
productions are case insensitive. The order in which <option>s appear
is irrelevant. That is, any two <attributedescription>s which consist
of the same <attributetype> and same set of <option>s are equivalent.
+
Examples of valid attribute descriptions:
+
2.5.4.0
cn;lang-de;lang-en
owner
+
An attribute description with an unrecognized attribute type is to be
treated as unrecognized. Servers SHALL treat an attribute description
with an unrecognized attribute option as unrecognized. Clients MAY
treat an unrecognized attribute option as a tagging option (see
Section 2.5.2.1).
+
All attributes of an entry must have distinct attribute descriptions.
+
2.5.1. Attribute Types
+
An attribute type governs whether the attribute can have multiple
values, the syntax and matching rules used to construct and compare
values of that attribute, and other functions.
+
+ If no equality matching is specified for the attribute type:
+ - the attribute (of the type) cannot be used for naming;
+
+
+
+
+Zeilenga LDAP Models [Page 12]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
+ - when adding the attribute (or replacing all values), no two values
+ may be equivalent (see 2.2);
+ - individual values of a multi-valued attribute are not to be
+ independently added or deleted;
+ - attribute value assertions (such as matching in search filters and
+ comparisons) using values of such a type cannot be performed.
+
+
+ Otherwise, the equality matching rule is to be used for the purposes
+ of evaluating attribute value assertions concerning the attribute
+ type.
+
+
The attribute type indicates whether the attribute is a user attribute
or an operational attribute. If operational, the attribute type
indicates the operational usage and whether the attribute is
modifiable by users or not. Operational attributes are discussed in
Section 3.4.
+
An attribute type (a subtype) may derive from a more generic attribute
type (a direct supertype). The following restrictions apply to
subtyping:
- a subtype must have the same usage as its direct supertype,
- - a subtype's syntax must be the same, or a refine of, its
+ - a subtype's syntax must be the same, or a refinement of, its
supertype's syntax, and
- a subtype must be collective [RFC3671] if its supertype is
collective.
-
-Zeilenga LDAP Models [Page 12]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
An attribute description consisting of a subtype and no options is
said to be the direct description subtype of the attribute description
consisting of the subtype's direct supertype and no options.
+
Each attribute type is identified by an object identifier (OID) and,
optionally, one or more short names (descriptors).
+
2.5.2. Attribute Options
+
There are multiple kinds of attribute description options. The LDAP
technical specification details one kind: tagging options.
+
Not all options can be associated with attributes held in the
directory. Tagging options can be.
+
Not all options can be used in conjunction with all attribute types.
In such cases, the attribute description is to be treated as
unrecognized.
+
An attribute description that contains mutually exclusive options
shall be treated as unrecognized. That is, "cn;x-bar;x-foo", where
+
+
+
+
+Zeilenga LDAP Models [Page 13]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
"x-foo" and "x-bar" are mutually exclusive, is to be treated as
unrecognized.
+
Other kinds of options may be specified in future documents. These
documents must detail how new kinds of options they define relate to
tagging options. In particular, these documents must detail whether
values, and how new kinds of options are treated in attribute
description hierarchies.
+
Options are represented as short case insensitive textual strings
conforming to the <option> production defined in Section 2.5 of this
document.
+
Procedures for registering options are detailed in BCP 64 [BCP64bis].
+
2.5.2.1. Tagging Options
+
Attributes held in the directory can have attribute descriptions with
any number of tagging options. Tagging options are never mutually
exclusive.
+
An attribute description with N tagging options is a direct
(description) subtype of all attribute descriptions of the same
-
-
-
-Zeilenga LDAP Models [Page 13]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
attribute type and all but one of the N options. If the attribute
type has a supertype, then the attribute description is also a direct
(description) subtype of the attribute description of the supertype
in [Schema]).
+
2.5.3. Attribute Description Hierarchies
+
An attribute description can be the direct subtype of zero or more
other attribute descriptions as indicated by attribute type subtyping
(as described in Section 2.5.1) or attribute tagging option subtyping
(as described in Section 2.5.2.1). These subtyping relationships are
used to form hierarchies of attribute descriptions and attributes.
+
As adapted from [X.501]:
+
Attribute hierarchies allow access to the DIB with varying degrees
of granularity. This is achieved by allowing the value components
of attributes to be accessed by using either their specific
+
+
+
+
+Zeilenga LDAP Models [Page 14]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
attribute description (a direct reference to the attribute) or by
a more generic attribute description (an indirect reference).
+
Semantically related attributes may be placed in a hierarchical
relationship, the more specialized being placed subordinate to the
more generalized. Searching for, or retrieving attributes and
the more specialized descriptions as well as for the quoted
description.
+
Where subordinate specialized descriptions are selected to be
returned as part of a search result these descriptions shall be
returned if available. Where the more general descriptions are
available. An attribute value shall always be returned as a value
of its own attribute description.
+
All of the attribute descriptions in an attribute hierarchy are
treated as distinct and unrelated descriptions for user
modification of entry content.
- An attribute value stored in a object or alias entry is of
+
+ An attribute value stored in an object or alias entry is of
precisely one attribute description. The description is indicated
when the value is originally added to the entry.
-
-Zeilenga LDAP Models [Page 14]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
For the purpose of subschema administration of the entry, a
specification that an attribute is required is fulfilled if the entry
contains a value of an attribute description belonging to an attribute
'CN' and 'CN;x-tag-option' are not allowed by "MAY name" (nor by "MUST
name").
+
For the purposes of other policy administration, unless stated
otherwise in the specification of the particular administrative model,
all of the attribute descriptions in an attribute hierarchy are
treated as distinct and unrelated descriptions.
-2.5.4. Attribute Values
- Attribute values conform to the defined syntax of the attribute.
- When an attribute is used for naming of the entry, one and only one
- value of the attribute is selected to appear in the Relative
- Distinguished Name. This value is known as a distinguished value.
- Only attributes whose descriptions have no options can be used for
- naming.
+Zeilenga LDAP Models [Page 15]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
2.6. Alias Entries
+
As adapted from [X.501]:
- An alias, or an alias name, for an object is a an alternative name
+
+ An alias, or an alias name, for an object is an alternative name
for an object or object entry which is provided by the use of
alias entries.
+
Each alias entry contains, within the 'aliasedObjectName'
attribute (known as the 'aliasedEntryName' attribute in X.500]), a
name of some object. The distinguished name of the alias entry is
thus also a name for this object.
- NOTE - The name within the 'aliasedObjectName' is said to be
-
-
-
-Zeilenga LDAP Models [Page 15]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
+ NOTE - The name within the 'aliasedObjectName' is said to be
pointed to by the alias. It does not have to be the
distinguished name of any entry.
+
The conversion of an alias name to an object name is termed
(alias) dereferencing and comprises the systematic replacement of
alias names, where found within a purported name, by the value of
the corresponding 'aliasedObjectName' attribute. The process may
require the examination of more than one alias entry.
+
Any particular entry in the DIT may have zero or more alias names.
It therefore follows that several alias entries may point to the
same entry. An alias entry may point to an entry that is not a
leaf entry and may point to another alias entry.
+
An alias entry shall have no subordinates, so that an alias entry
is always a leaf entry.
+
Every alias entry shall belong to the 'alias' object class.
+
An entry with the 'alias' object class must also belong to an object
class (or classes), or be governed by a DIT content rule, which allows
suitable naming attributes to be present.
+
Example:
dn: cn=bar,dc=example,dc=com
objectClass: top
aliasedObjectName: cn=foo,dc=example,dc=com
+
2.6.1. 'alias' object class
+
+
+
+
+Zeilenga LDAP Models [Page 16]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
Alias entries belong to the 'alias' object class.
+
( 2.5.6.1 NAME 'alias'
SUP top STRUCTURAL
MUST aliasedObjectName )
+
2.6.2. 'aliasedObjectName' attribute type
+
The 'aliasedObjectName' attribute holds the name of the entry an alias
points to. The 'aliasedObjectName' attribute is known as the
'aliasedEntryName' attribute in X.500.
- ( 2.5.4.1 NAME 'aliasedObjectName'
-
-
-
-Zeilenga LDAP Models [Page 16]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
+ ( 2.5.4.1 NAME 'aliasedObjectName'
EQUALITY distinguishedNameMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.12
SINGLE-VALUE )
+
The 'distinguishedNameMatch' matching rule and the DistinguishedName
(1.3.6.1.4.1.1466.115.121.1.12) syntax are defined in [Syntaxes].
+
3. Directory Administrative and Operational Information
+
This section discusses select aspects of the X.500 Directory
Administrative and Operational Information model [X.501]. LDAP
implementations MAY support other aspects of this model.
+
3.1. Subtrees
+
As defined in [X.501]:
+
A subtree is a collection of object and alias entries situated at
the vertices of a tree. Subtrees do not contain subentries. The
prefix sub, in subtree, emphasizes that the base (or root) vertex
of this tree is usually subordinate to the root of the DIT.
+
A subtree begins at some vertex and extends to some identifiable
lower boundary, possibly extending to leaves. A subtree is always
defined within a context which implicitly bounds the subtree. For
replicated area are bounded by a naming context.
-3.2. Subentries
- A subentry is a "special sort of entry, known by the Directory, used
+3.2. Subentries
+
+
+ A subentry is a "special sort of entry, known by the Directory, used
+
+
+
+
+Zeilenga LDAP Models [Page 17]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
to hold information associated with a subtree or subtree refinement"
[X.501]. Subentries are used in Directory to hold for administrative
and operational purposes as defined in [X.501]. Their use in LDAP is
detailed in [RFC3672].
+
The term "(sub)entry" in this specification indicates that servers
implementing X.500(93) models are, in accordance with X.500(93) as
described in [RFC3672], to use a subentry and that other servers are
-
-Zeilenga LDAP Models [Page 17]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
3.3. The 'objectClass' attribute
+
Each entry in the DIT has an 'objectClass' attribute.
+
( 2.5.4.0 NAME 'objectClass'
EQUALITY objectIdentifierMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.38 )
+
The 'objectIdentifierMatch' matching rule and the OBJECT IDENTIFIER
(1.3.6.1.4.1.1466.115.121.1.38) syntax are defined in [Syntaxes].
+
The 'objectClass' attribute specifies the object classes of an entry,
which (among other things) is used in conjunction with the controlling
schema to determine the permitted attributes of an entry. Values of
this attribute can be modified by clients, but the 'objectClass'
attribute cannot be removed.
+
Servers which follow X.500(93) models SHALL restrict modifications of
this attribute to prevent the basic structural class of the entry from
being changed. That is, one cannot change a 'person' into a
'country'.
+
When creating an entry or adding an 'objectClass' value to an entry,
all superclasses of the named classes SHALL be implicitly added as
well if not already present. That is, if the auxiliary class 'x-a' is
a subclass of the class 'x-b', adding 'x-a' to 'objectClass' causes
'x-b' to be implicitly added (if is not already present).
+
Servers SHALL restrict modifications of this attribute to prevent
superclasses of remaining 'objectClass' values from being deleted.
That is, if the auxiliary class 'x-a' is a subclass of the auxiliary
class 'x-b' and the 'objectClass' attribute contains 'x-a' and 'x-b',
an attempt to delete only 'x-b' from the 'objectClass' attribute is an
+
+
+
+
+Zeilenga LDAP Models [Page 18]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
error.
+
3.4. Operational attributes
+
Some attributes, termed operational attributes, are used or maintained
by servers for administrative and operational purposes. As stated in
[X.501]: "There are three varieties of operational attributes:
Directory operational attributes, DSA-shared operational attributes,
and DSA-specific operational attributes."
+
A directory operational attribute is used to represent operational
and/or administrative information in the Directory Information Model.
This includes operational attributes maintained by the server (e.g.
'createTimestamp') as well as operational attributes which hold values
-
-
-
-Zeilenga LDAP Models [Page 18]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
administrated by the user (e.g. 'ditContentRules').
+
A DSA-shared operational attribute is used to represent information of
the DSA Information Model which is shared between DSAs.
+
A DSA-specific operational attribute is used to represent information
of the DSA Information Model which is specific to the DSA (though, in
some cases, may be derived from information shared between DSAs)
(e.g., 'namingContexts').
+
The DSA Information Model operational attributes are detailed in
[X.501].
+
Operational attributes are not normally visible. They are not
returned in search results unless explicitly requested by name.
+
Not all operational attributes are user modifiable.
+
Entries may contain, among others, the following operational
attributes:
+
- creatorsName: the Distinguished Name of the user who added this
entry to the directory,
+
- createTimestamp: the time this entry was added to the directory,
+
- modifiersName: the Distinguished Name of the user who last
modified this entry, and
+
- modifyTimestamp: the time this entry was last modified.
+
Servers SHOULD maintain the 'creatorsName', 'createTimestamp',
'modifiersName', and 'modifyTimestamp' attributes for all entries of
+
+
+
+
+Zeilenga LDAP Models [Page 19]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
the DIT.
+
3.4.1. 'creatorsName'
+
This attribute appears in entries which were added using the protocol
(e.g., using the Add operation). The value is the distinguished name
of the creator.
+
( 2.5.18.3 NAME 'creatorsName'
EQUALITY distinguishedNameMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.12
USAGE directoryOperation )
-
-
-Zeilenga LDAP Models [Page 19]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
The 'distinguishedNameMatch' matching rule and the DistinguishedName
(1.3.6.1.4.1.1466.115.121.1.12) syntax are defined in [Syntaxes].
+
3.4.2. 'createTimestamp'
+
This attribute appears in entries which were added using the protocol
(e.g., using the Add operation). The value is the time the entry was
added.
+
( 2.5.18.1 NAME 'createTimestamp'
EQUALITY generalizedTimeMatch
ORDERING generalizedTimeOrderingMatch
SINGLE-VALUE NO-USER-MODIFICATION
USAGE directoryOperation )
+
The 'generalizedTimeMatch' and 'generalizedTimeOrderingMatch' matching
rules and the GeneralizedTime (1.3.6.1.4.1.1466.115.121.1.24) syntax
are defined in [Syntaxes].
+
3.4.3. 'modifiersName'
+
This attribute appears in entries which have been modified using the
protocol (e.g., using Modify operation). The value is the
distinguished name of the last modifier.
+
( 2.5.18.4 NAME 'modifiersName'
EQUALITY distinguishedNameMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.12
SINGLE-VALUE NO-USER-MODIFICATION
USAGE directoryOperation )
+
+
+
+Zeilenga LDAP Models [Page 20]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
The 'distinguishedNameMatch' matching rule and the DistinguishedName
(1.3.6.1.4.1.1466.115.121.1.12) syntax are defined in [Syntaxes].
+
3.4.4. 'modifyTimestamp'
+
This attribute appears in entries which have been modified using the
protocol (e.g., using the Modify operation). The value is the time
the entry was last modified.
+
( 2.5.18.2 NAME 'modifyTimestamp'
EQUALITY generalizedTimeMatch
ORDERING generalizedTimeOrderingMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.24
-
-
-
-Zeilenga LDAP Models [Page 20]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
SINGLE-VALUE NO-USER-MODIFICATION
USAGE directoryOperation )
+
The 'generalizedTimeMatch' and 'generalizedTimeOrderingMatch' matching
rules and the GeneralizedTime (1.3.6.1.4.1.1466.115.121.1.24) syntax
are defined in [Syntaxes].
+
3.4.5. 'structuralObjectClass'
+
This attribute indicates the structural object class of the entry.
+
( 2.5.21.9 NAME 'structuralObjectClass'
EQUALITY objectIdentifierMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.38
SINGLE-VALUE NO-USER-MODIFICATION
USAGE directoryOperation )
+
The 'objectIdentifierMatch' matching rule and OBJECT IDENTIFIER
(1.3.6.1.4.1.1466.115.121.1.38) syntax is defined in [Syntaxes].
+
3.4.6. 'governingStructureRule'
+
This attribute indicates the structure rule governing the entry.
+
( 2.5.21.10 NAME 'governingStructureRule'
EQUALITY integerMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.27
SINGLE-VALUE NO-USER-MODIFICATION
USAGE directoryOperation )
+
The 'integerMatch' matching rule and INTEGER
(1.3.6.1.4.1.1466.115.121.1.27) syntax is defined in [Syntaxes].
+
+
+Zeilenga LDAP Models [Page 21]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
4. Directory Schema
+
As defined in [X.501]:
+
The Directory Schema is a set of definitions and constraints
concerning the structure of the DIT, the possible ways entries are
named, the information that can be held in an entry, the
be matched in attribute value and matching rule assertions.
-
-
-Zeilenga LDAP Models [Page 21]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
NOTE 1 - The schema enables the Directory system to, for example:
+
- prevent the creation of subordinate entries of the wrong
object-class (e.g. a country as a subordinate of a person);
+
- prevent the addition of attribute-types to an entry
inappropriate to the object-class (e.g. a serial number to a
person's entry);
+
- prevent the addition of an attribute value of a syntax not
matching that defined for the attribute-type (e.g. a printable
string to a bit string).
+
Formally, the Directory Schema comprises a set of:
+
a) Name Form definitions that define primitive naming relations
for structural object classes;
+
b) DIT Structure Rule definitions that define the names that
entries may have and the ways in which the entries may be
related to one another in the DIT;
+
c) DIT Content Rule definitions that extend the specification of
allowable attributes for entries beyond those indicated by the
structural object classes of the entries;
+
d) Object Class definitions that define the basic set of mandatory
and optional attributes that shall be present, and may be
present, respectively, in an entry of a given class, and which
indicate the kind of object class that is being defined;
+
e) Attribute Type definitions that identify the object identifier
by which an attribute is known, its syntax, associated matching
rules, whether it is an operational attribute and if so its
type, whether it is a collective attribute, whether it is
permitted to have multiple values and whether or not it is
+
+
+
+
+Zeilenga LDAP Models [Page 22]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
derived from another attribute type;
- f) Matching Rule definitions that define matching rules.
- And in LDAP:
+ f) Matching Rule definitions that define matching rules.
- g) LDAP Syntax definitions that define encodings used in LDAP.
+ And in LDAP:
-4.1. Schema Definitions
- Schema definitions in this section are described using ABNF and rely
+ g) LDAP Syntax definitions that define encodings used in LDAP.
-Zeilenga LDAP Models [Page 22]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
+4.1. Schema Definitions
+ Schema definitions in this section are described using ABNF and rely
on the common productions specified in Section 1.2 as well as these:
+
noidlen = numericoid [ LCURLY len RCURLY ]
len = number
+
oids = oid / ( LPAREN WSP oidlist WSP RPAREN )
oidlist = oid *( WSP DOLLAR WSP oid )
+
extensions = *( SP xstring SP qdstrings )
- xstring = "X" HYPHEN 1*( UALPHA / HYPHEN / USCORE )
+ xstring = "X" HYPHEN 1*( ALPHA / HYPHEN / USCORE )
+
qdescrs = qdescr / ( LPAREN WSP qdescrlist WSP RPAREN )
qdescrlist = [ qdescr *( SP qdescr ) ]
qdescr = SQUOTE descr SQUOTE
+
qdstrings = qdstring / ( LPAREN WSP qdstringlist WSP RPAREN )
qdstringlist = [ qdstring *( SP qdstring ) ]
qdstring = SQUOTE dstring SQUOTE
dstring = 1*( QS / QQ / QUTF8 ) ; escaped UTF-8 string
+
QQ = ESC %x32 %x37 ; "\27"
QS = ESC %x35 ( %x43 / %x63 ) ; "\5C" / "\5c"
+
; Any UTF-8 encoded Unicode character
; except %x27 ("'") and %x5C ("\")
QUTF8 = QUTF1 / UTFMB
+
; Any ASCII character except %x27 ("'") and %x5C ("\")
QUTF1 = %x00-26 / %x28-5B / %x5D-7F
+
Schema definitions in this section also share a number of common
terms.
+
The NAME field provides a set of short names (descriptors) which are
- be used as aliases for the OID.
+ to be used as aliases for the OID.
+
+
+
+
+
+Zeilenga LDAP Models [Page 23]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
The DESC field optionally allows a descriptive string to be provided
by the directory administrator and/or implementor. While
specifications may suggest a descriptive string, there is no
requirement that the suggested (or any) descriptive string be used.
+
The OBSOLETE field, if present, indicates the element is not active.
+
Implementors should note that future versions of this document may
expand these definitions to include additional terms. Terms whose
identifier begins with "X-" are reserved for private experiments, and
-
-Zeilenga LDAP Models [Page 23]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
4.1.1. Object Class Definitions
+
Object Class definitions are written according to the ABNF:
+
ObjectClassDescription = LPAREN WSP
numericoid ; object identifier
[ SP "NAME" SP qdescrs ] ; short names (descriptors)
[ SP "MAY" SP oids ] ; attribute types
extensions WSP RPAREN
+
kind = "ABSTRACT" / "STRUCTURAL" / "AUXILIARY"
+
where:
<numericoid> is object identifier assigned to this object class;
NAME <qdescrs> are short names (descriptors) identifying this object
<extensions> describe extensions.
+
4.1.2. Attribute Types
+
Attribute Type definitions are written according to the ABNF:
+
+
+
+
+Zeilenga LDAP Models [Page 24]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
AttributeTypeDescription = LPAREN WSP
numericoid ; object identifier
[ SP "NAME" SP qdescrs ] ; short names (descriptors)
[ SP "SINGLE-VALUE" ] ; single-value
[ SP "COLLECTIVE" ] ; collective
[ SP "NO-USER-MODIFICATION" ] ; not user modifiable
-
-
-
-Zeilenga LDAP Models [Page 24]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
[ SP "USAGE" SP usage ] ; usage
extensions WSP RPAREN ; extensions
+
usage = "userApplications" / ; user
"directoryOperation" / ; directory operational
"distributedOperation" / ; DSA-shared operational
"dSAOperation" ; DSA-specific operational
+
where:
<numericoid> is object identifier assigned to this attribute type;
NAME <qdescrs> are short names (descriptors) identifying this
DESC <qdstring> is a short descriptive string;
OBSOLETE indicates this attribute type is not active;
SUP oid specifies the direct supertype of this type;
- EQUALITY, ORDERING, SUBSTRING provide the oid of the equality,
+ EQUALITY, ORDERING, SUBSTR provide the oid of the equality,
ordering, and substrings matching rules, respectively;
SYNTAX identifies value syntax by object identifier and may suggest
a minimum upper bound;
+ SINGLE-VALUE indicates attributes of this type are restricted to a
+ single value;
COLLECTIVE indicates this attribute type is collective
[X.501][RFC3671];
NO-USER-MODIFICATION indicates this attribute type is not user
USAGE indicates the application of this attribute type; and
<extensions> describe extensions.
+
Each attribute type description must contain at least one of the SUP
or SYNTAX fields. If no SYNTAX field is provided, the attribute type
description takes its value from the supertype.
+
If SUP field is provided, the EQUALITY, ORDERING, and SUBSTRING
fields, if not specified, take their value from the supertype.
+
+
+
+
+Zeilenga LDAP Models [Page 25]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
Usage of userApplications, the default, indicates that attributes of
this type represent user information. That is, they are user
attributes.
+
A usage of directoryOperation, distributedOperation, or dSAOperation
indicates that attributes of this type represent operational and/or
administrative information. That is, they are operational attributes.
+
directoryOperation usage indicates that the attribute of this type is
a directory operational attribute. distributedOperation usage
indicates that the attribute of this DSA-shared usage operational
attribute. dSAOperation usage indicates that the attribute of this
type is a DSA-specific operational attribute.
- COLLECTIVE requires usage userApplications. Use of collective
-
-
-
-Zeilenga LDAP Models [Page 25]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
+ COLLECTIVE requires usage userApplications. Use of collective
attribute types in LDAP is discussed in [RFC3671].
+
NO-USER-MODIFICATION requires an operational usage.
+
Note that the <AttributeTypeDescription> does not list the matching
rules which can be used with that attribute type in an extensibleMatch
search filter [Protocol]. This is done using the 'matchingRuleUse'
attribute described in Section 4.1.4.
+
This document refines the schema description of X.501 by requiring
that the SYNTAX field in an <AttributeTypeDescription> be a string
representation of an object identifier for the LDAP string syntax
definition with an optional indication of the suggested minimum bound
of a value of this attribute.
+
A suggested minimum upper bound on the number of characters in a value
with a string-based syntax, or the number of bytes in a value for all
other syntaxes, may be indicated by appending this bound count inside
since UTF-8 [RFC3629] is a variable-length encoding.
+
4.1.3. Matching Rules
+
Matching rules are used in performance of attribute value assertions,
such as in performance of a Compare operation. They are also used in
evaluation of a Search filters, in determining which individual values
are be added or deleted during performance of a Modify operation, and
- used in comparison of distinguished names
+
+
+
+
+Zeilenga LDAP Models [Page 26]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
+ used in comparison of distinguished names.
+
Each matching rule is identified by an object identifier (OID) and,
optionally, one or more short names (descriptors).
+
Matching rule definitions are written according to the ABNF:
+
MatchingRuleDescription = LPAREN WSP
numericoid ; object identifier
[ SP "NAME" SP qdescrs ] ; short names (descriptors)
extensions WSP RPAREN ; extensions
-
-
-Zeilenga LDAP Models [Page 26]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
where:
<numericoid> is object identifier assigned to this matching rule;
NAME <qdescrs> are short names (descriptors) identifying this
<extensions> describe extensions.
+
4.1.4. Matching Rule Uses
+
A matching rule use lists the attributes which are suitable for use
with an extensibleMatch search filter.
+
Matching rule use descriptions are written according to the following
ABNF:
+
MatchingRuleUseDescription = LPAREN WSP
numericoid ; object identifier
[ SP "NAME" SP qdescrs ] ; short names (descriptors)
SP "APPLIES" SP oids ; attribute types
extensions WSP RPAREN ; extensions
+
where:
<numericoid> is the object identifier of the matching rule
associated with this matching rule use description;
NAME <qdescrs> are short names (descriptors) identifying this
matching rule use;
DESC <qdstring> is a short descriptive string;
+
+
+
+
+Zeilenga LDAP Models [Page 27]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
OBSOLETE indicates this matching rule use is not active;
APPLIES provides a list of attribute types the matching rule applies
to; and
<extensions> describe extensions.
+
4.1.5. LDAP Syntaxes
+
LDAP Syntaxes of (attribute and assertion) values are described in
terms of ASN.1 [X.680] and, optionally, have an octet string encoding
known as the LDAP-specific encoding. Commonly, the LDAP-specific
- encoding is constrained to string of Unicode [Unicode] characters in
+ encoding is constrained to a string of Unicode [Unicode] characters in
UTF-8 [RFC3629] form.
- Each LDAP syntax is identified by an object identifier (OID).
-
-
-Zeilenga LDAP Models [Page 27]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
+ Each LDAP syntax is identified by an object identifier (OID).
LDAP syntax definitions are written according to the ABNF:
+
SyntaxDescription = LPAREN WSP
numericoid ; object identifier
[ SP "DESC" SP qdstring ] ; description
extensions WSP RPAREN ; extensions
+
where:
- <numericoid> is object identifier assigned to this LDAP syntax;
+ <numericoid> is the object identifier assigned to this LDAP syntax;
DESC <qdstring> is a short descriptive string; and
<extensions> describe extensions.
+
4.1.6. DIT Content Rules
+
A DIT content rule is a "rule governing the content of entries of a
particular structural object class" [X.501].
+
For DIT entries of a particular structural object class, a DIT content
rule specifies which auxiliary object classes the entries are allowed
to belong to and which additional attributes (by type) are required,
allowed or not allowed to appear in the entries.
+
The list of precluded attributes cannot include any attribute listed
- as mandatory in rule, the structural object class, or any of the
+ as mandatory in the rule, the structural object class, or any of the
allowed auxiliary object classes.
+
Each content rule is identified by the object identifier, as well as
any short names (descriptors), of the structural object class it
applies to.
+
An entry may only belong to auxiliary object classes listed in the
+
+
+
+
+Zeilenga LDAP Models [Page 28]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
governing content rule.
+
An entry must contain all attributes required by the object classes
- the entry belongs to as well as all attributed required by the
+ the entry belongs to as well as all attributes required by the
governing content rule.
+
An entry may contain any non-precluded attributes allowed by the
object classes the entry belongs to as well as all attributes allowed
by the governing content rule.
+
An entry cannot include any attribute precluded by the governing
content rule.
+
An entry is governed by (if present and active in the subschema) the
DIT content rule which applies to the structural object class of the
entry (see Section 2.4.2). If no active rule is present for the
-
-
-
-Zeilenga LDAP Models [Page 28]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
entry's structural object class, the entry's content is governed by
the structural object class (and possibly other aspects of user and
system schema). DIT content rules for superclasses of the structural
object class of an entry are not applicable to that entry.
+
DIT content rule descriptions are written according to the ABNF:
+
DITContentRuleDescription = LPAREN WSP
numericoid ; object identifier
[ SP "NAME" SP qdescrs ] ; short names (descriptors)
[ SP "NOT" SP oids ] ; attribute types
extensions WSP RPAREN ; extensions
+
where:
<numericoid> is the object identifier of the structural object class
associated with this DIT content rule;
<extensions> describe extensions.
+
+
+
+Zeilenga LDAP Models [Page 29]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
4.1.7. DIT Structure Rules and Name Forms
+
It is sometimes desirable to regulate where object and alias entries
can be placed in the DIT and how they can be named based upon their
structural object class.
+
4.1.7.1. DIT Structure Rules
+
A DIT structure rule is a "rule governing the structure of the DIT by
specifying a permitted superior to subordinate entry relationship. A
structure rule relates a name form, and therefore a structural object
class, to superior structure rules. This permits entries of the
structural object class identified by the name form to exist in the
DIT as subordinates to entries governed by the indicated superior
-
-
-
-Zeilenga LDAP Models [Page 29]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
structure rules" [X.501].
+
DIT structure rule descriptions are written according to the ABNF:
+
DITStructureRuleDescription = LPAREN WSP
ruleid ; rule identifier
[ SP "NAME" SP qdescrs ] ; short names (descriptors)
[ SP "SUP" ruleids ] ; superior rules
extensions WSP RPAREN ; extensions
+
ruleids = ruleid / ( LPAREN WSP ruleidlist WSP RPAREN )
ruleidlist = ruleid *( SP ruleid )
ruleid = number
+
where:
<ruleid> is the rule identifier of this DIT structure rule;
NAME <qdescrs> are short names (descriptors) identifying this DIT
SUP identifies superior rules (by rule id); and
<extensions> describe extensions.
+
If no superior rules are identified, the DIT structure rule applies
to an autonomous administrative point (e.g. the root vertex of the
subtree controlled by the subschema) [X.501].
+
+
+
+
+Zeilenga LDAP Models [Page 30]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
4.1.7.2. Name Forms
+
A name form "specifies a permissible RDN for entries of a particular
structural object class. A name form identifies a named object
class and one or more attribute types to be used for naming (i.e.
for the RDN). Name forms are primitive pieces of specification
used in the definition of DIT structure rules" [X.501].
+
Each name form indicates the structural object class to be named,
a set of required attribute types, and a set of allowed attribute
types. A particular attribute type cannot be in both sets.
+
Entries governed by the form must be named using a value from each
required attribute type and zero or more values from the allowed
attribute types.
-
-Zeilenga LDAP Models [Page 30]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
Each name form is identified by an object identifier (OID) and,
optionally, one or more short names (descriptors).
+
Name form descriptions are written according to the ABNF:
+
NameFormDescription = LPAREN WSP
numericoid ; object identifier
[ SP "NAME" SP qdescrs ] ; short names (descriptors)
[ SP "MAY" SP oids ] ; attribute types
extensions WSP RPAREN ; extensions
+
where:
<numericoid> is object identifier which identifies this name form;
NAME <qdescrs> are short names (descriptors) identifying this name
naming attributes for this name form; and
<extensions> describe extensions.
+
All attribute types in the required ("MUST") and allowed ("MAY") lists
shall be different.
+
4.2. Subschema Subentries
+
+
+
+
+Zeilenga LDAP Models [Page 31]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
Subschema (sub)entries are used for administering information about
the directory schema. A single subschema (sub)entry contains all
schema definitions (see Section 4.1) used by entries in a particular
part of the directory tree.
+
Servers which follow X.500(93) models SHOULD implement subschema using
the X.500 subschema mechanisms (as detailed in Section 12 of [X.501]),
and so these are not ordinary object entries but subentries (see
Section 3.2). LDAP clients SHOULD NOT assume that servers implement
any of the other aspects of X.500 subschema.
+
Servers MAY allow subschema modification. Procedures for subschema
modification are discussed in Section 14.5 of [X.501].
+
A server which masters entries and permits clients to modify these
entries SHALL implement and provide access to these subschema
-
-
-
-Zeilenga LDAP Models [Page 31]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
(sub)entries including providing a 'subschemaSubentry' attribute in
- each modifiable entry. This so clients may discover the attributes
+ each modifiable entry. This is so clients may discover the attributes
and object classes which are permitted to be present. It is strongly
RECOMMENDED that all other servers implement this as well.
+
The value of the 'subschemaSubentry' attribute is the name of the
subschema (sub)entry holding the subschema controlling the entry.
+
( 2.5.18.10 NAME 'subschemaSubentry'
EQUALITY distinguishedNameMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.12
NO-USER-MODIFICATION SINGLE-VALUE
USAGE directoryOperation )
+
The 'distinguishedNameMatch' matching rule and the DistinguishedName
(1.3.6.1.4.1.1466.115.121.1.12) syntax are defined in [Syntaxes].
+
Subschema is held in (sub)entries belonging to the subschema auxiliary
object class.
+
( 2.5.20.1 NAME 'subschema' AUXILIARY
MAY ( dITStructureRules $ nameForms $ ditContentRules $
objectClasses $ attributeTypes $ matchingRules $
matchingRuleUse ) )
+
The 'ldapSyntaxes' operational attribute may also be present in
subschema entries.
+
Servers MAY provide additional attributes (described in other
documents) in subschema (sub)entries.
+
Servers SHOULD provide the attributes 'createTimestamp' and
+
+
+
+
+Zeilenga LDAP Models [Page 32]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
'modifyTimestamp' in subschema (sub)entries, in order to allow clients
to maintain their caches of schema information.
+
The following subsections provide attribute type definitions for each
of schema definition attribute types.
+
4.2.1. 'objectClasses'
+
This attribute holds definitions of object classes.
+
( 2.5.21.6 NAME 'objectClasses'
EQUALITY objectIdentifierFirstComponentMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.37
USAGE directoryOperation )
-
-
-Zeilenga LDAP Models [Page 32]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
The 'objectIdentifierFirstComponentMatch' matching rule and the
ObjectClassDescription (1.3.6.1.4.1.1466.115.121.1.37) syntax are
defined in [Syntaxes].
+
4.2.2. 'attributeTypes'
+
This attribute holds definitions of attribute types.
+
( 2.5.21.5 NAME 'attributeTypes'
EQUALITY objectIdentifierFirstComponentMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.3
USAGE directoryOperation )
+
The 'objectIdentifierFirstComponentMatch' matching rule and the
AttributeTypeDescription (1.3.6.1.4.1.1466.115.121.1.3) syntax are
defined in [Syntaxes].
+
4.2.3. 'matchingRules'
+
This attribute holds definitions of matching rules.
+
( 2.5.21.4 NAME 'matchingRules'
EQUALITY objectIdentifierFirstComponentMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.30
USAGE directoryOperation )
+
The 'objectIdentifierFirstComponentMatch' matching rule and the
MatchingRuleDescription (1.3.6.1.4.1.1466.115.121.1.30) syntax are
defined in [Syntaxes].
+
+
+
+Zeilenga LDAP Models [Page 33]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
4.2.4 'matchingRuleUse'
+
This attribute holds definitions of matching rule uses.
+
( 2.5.21.8 NAME 'matchingRuleUse'
EQUALITY objectIdentifierFirstComponentMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.31
USAGE directoryOperation )
+
The 'objectIdentifierFirstComponentMatch' matching rule and the
MatchingRuleUseDescription (1.3.6.1.4.1.1466.115.121.1.31) syntax are
defined in [Syntaxes].
-4.2.5. 'ldapSyntaxes'
-
-
-Zeilenga LDAP Models [Page 33]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
+4.2.5. 'ldapSyntaxes'
This attribute holds definitions of LDAP syntaxes.
+
( 1.3.6.1.4.1.1466.101.120.16 NAME 'ldapSyntaxes'
EQUALITY objectIdentifierFirstComponentMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.54
USAGE directoryOperation )
+
The 'objectIdentifierFirstComponentMatch' matching rule and the
SyntaxDescription (1.3.6.1.4.1.1466.115.121.1.54) syntax are defined
in [Syntaxes].
+
4.2.6. 'dITContentRules'
+
This attribute lists DIT Content Rules which are present in the
subschema.
+
( 2.5.21.2 NAME 'dITContentRules'
EQUALITY objectIdentifierFirstComponentMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.16
USAGE directoryOperation )
+
The 'objectIdentifierFirstComponentMatch' matching rule and the
DITContentRuleDescription (1.3.6.1.4.1.1466.115.121.1.16) syntax are
defined in [Syntaxes].
+
4.2.7. 'dITStructureRules'
- This attribute lists DIT Structure Rules which present in the
+
+ This attribute lists DIT Structure Rules which are present in the
subschema.
+
+
+
+
+Zeilenga LDAP Models [Page 34]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
( 2.5.21.1 NAME 'dITStructureRules'
EQUALITY integerFirstComponentMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.17
USAGE directoryOperation )
+
The 'integerFirstComponentMatch' matching rule and the
DITStructureRuleDescription (1.3.6.1.4.1.1466.115.121.1.17) syntax are
defined in [Syntaxes].
+
4.2.8 'nameForms'
+
This attribute lists Name Forms which are in force.
+
( 2.5.21.7 NAME 'nameForms'
EQUALITY objectIdentifierFirstComponentMatch
-
-
-
-Zeilenga LDAP Models [Page 34]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
SYNTAX 1.3.6.1.4.1.1466.115.121.1.35
USAGE directoryOperation )
+
The 'objectIdentifierFirstComponentMatch' matching rule and the
NameFormDescription (1.3.6.1.4.1.1466.115.121.1.35) syntax are defined
in [Syntaxes].
+
4.3. 'extensibleObject' object class
+
The 'extensibleObject' auxiliary object class allows entries that
belong to it to hold any user attribute. The set of allowed attribute
types of this object class is implicitly the set of all attribute
types of userApplications usage.
+
( 1.3.6.1.4.1.1466.101.120.111 NAME 'extensibleObject'
SUP top AUXILIARY )
+
The mandatory attributes of the other object classes of this entry are
still required to be present and any precluded attributes are still
not allowed to be present.
+
4.4. Subschema Discovery
+
To discover the DN of the subschema (sub)entry holding the subschema
controlling a particular entry, a client reads that entry's
'subschemaSubentry' operational attribute. To read schema attributes
from the subschema (sub)entry, clients MUST issue a Search operation
[Protocol] where baseObject is the DN of the subschema (sub)entry,
scope is baseObject, filter is "(objectClass=subschema)" [Filters],
+
+
+
+
+Zeilenga LDAP Models [Page 35]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
and attributes field lists the names of the desired schema attributes
(as they are operational). Note: the "(objectClass=subschema)" filter
allows LDAP servers which gateway to X.500 to detect that subentry
information is being requested.
+
Clients SHOULD NOT assume a published subschema is complete nor assume
the server supports all of the schema elements it publishes nor assume
the server does not support an unpublished element.
+
5. DSA (Server) Informational Model
+
The LDAP protocol assumes there are one or more servers which jointly
provide access to a Directory Information Tree (DIT). The server
holding the original information is called the "master" (for that
information). Servers which hold copies of the original information
-
-
-
-Zeilenga LDAP Models [Page 35]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
are referred to as "shadowing" or "caching" servers.
+
As defined in [X.501]:
+
context prefix: The sequence of RDNs leading from the Root of the
DIT to the initial vertex of a naming context; corresponds to
the distinguished name of that vertex.
+
and:
+
naming context: A subtree of entries held in a single master DSA.
+
That is, a naming context is the largest collection of entries,
starting at an entry that is mastered by a particular server, and
including all its subordinates and their subordinates, down to the
entries which are mastered by different servers. The context prefix
is the name of the initial entry.
+
The root of the DIT is a DSA-specific Entry (DSE) and not part of any
naming context (or any subtree); each server has different attribute
values in the root DSE.
+
5.1. Server-specific Data Requirements
+
An LDAP server SHALL provide information about itself and other
information that is specific to each server. This is represented as a
group of attributes located in the root DSE, which is named with the
DN with zero RDNs (whose [LDAPDN] representation is as the zero-length
string).
+
These attributes are retrievable, subject to access control and other
+
+
+
+
+Zeilenga LDAP Models [Page 36]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
restrictions, if a client performs a Search operation [Protocol] with
an empty baseObject, scope of baseObject, the filter "(objectClass=*)"
[Filters], and with the attributes field listing the names of the
operational, and like other operational attributes, are not returned
in search requests unless requested by name.
+
The root DSE SHALL NOT be included if the client performs a subtree
search starting from the root.
+
Servers may allow clients to modify attributes of the root DSE where
appropriate.
+
The following attributes of the root DSE are defined in [Syntaxes].
Additional attributes may be defined in other documents.
-
-
-Zeilenga LDAP Models [Page 36]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
- altServer: alternative servers;
+
- namingContexts: naming contexts;
+
- supportedControl: recognized LDAP controls;
+
- supportedExtension: recognized LDAP extended operations;
+
- supportedLDAPVersion: LDAP versions supported; and
+
- supportedSASLMechanisms: recognized Simple Authentication and
Security Layers (SASL) [SASL] mechanisms.
+
The values provided for these attributes may depend on
session-specific and other factors. For example, a server supporting
the SASL EXTERNAL mechanism might only list "EXTERNAL" when the
client's identity has been established by a lower level. See
[AuthMeth].
+
The root DSE may also include a 'subschemaSubentry' attribute. If so,
it refers to the subschema (sub)entry holding the schema controlling
the root DSE. Clients SHOULD NOT assume that this subschema
subschema discovery procedures are provided in Section 4.4.
+
5.1.1. 'altServer'
+
The 'altServer' attribute lists URIs referring to alternative servers
which may be contacted when this server becomes unavailable. URIs for
servers implementing the LDAP are written according to [LDAPURL].
Other kinds of URIs may be provided. If the server does not know of
+
+
+
+
+Zeilenga LDAP Models [Page 37]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
any other servers which could be used this attribute will be absent.
Clients may cache this information in case their preferred server
later becomes unavailable.
+
( 1.3.6.1.4.1.1466.101.120.6 NAME 'altServer'
SYNTAX 1.3.6.1.4.1.1466.115.121.1.26
USAGE dSAOperation )
+
The IA5String (1.3.6.1.4.1.1466.115.121.1.26) syntax is defined in
[Syntaxes].
+
5.1.2. 'namingContexts'
+
The 'namingContexts' attribute lists the context prefixes of the
naming contexts the server masters or shadows (in part or in whole).
-
-
-
-Zeilenga LDAP Models [Page 37]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
If the server is a first-level DSA [X.501], it should list (in
addition) an empty string (indicating the root of the DIT). If the
server does not master or shadow any information (e.g. it is an LDAP
attribute will have a single value, and that value will be the empty
string (indicating the root of the DIT).
+
This attribute may be used, for example, to select a suitable entry
name for subsequent operations with this server.
+
( 1.3.6.1.4.1.1466.101.120.5 NAME 'namingContexts'
SYNTAX 1.3.6.1.4.1.1466.115.121.1.12
USAGE dSAOperation )
+
The DistinguishedName (1.3.6.1.4.1.1466.115.121.1.12) syntax is
defined in [Syntaxes].
+
5.1.3. 'supportedControl'
+
The 'supportedControl' attribute lists object identifiers identifying
the request controls [Protocol] the server supports. If the server
does not support any request controls, this attribute will be absent.
Object identifiers identifying response controls need not be listed.
+
Procedures for registering object identifiers used to discovery of
protocol mechanisms are detailed in BCP 64 [BCP64bis].
+
( 1.3.6.1.4.1.1466.101.120.13 NAME 'supportedControl'
SYNTAX 1.3.6.1.4.1.1466.115.121.1.38
USAGE dSAOperation )
+
+
+
+Zeilenga LDAP Models [Page 38]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
The OBJECT IDENTIFIER (1.3.6.1.4.1.1466.115.121.1.38) syntax is
defined in [Syntaxes].
+
5.1.4. 'supportedExtension'
+
The 'supportedExtension' attribute lists object identifiers
identifying the extended operations [Protocol] which the server
supports. If the server does not support any extended operations,
this attribute will be absent.
+
An extended operation generally consists of an extended request and an
extended response but may also include other protocol data units (such
as intermediate responses). The object identifier assigned to the
extended request is used to identify the extended operation. Other
-
-
-
-Zeilenga LDAP Models [Page 38]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
object identifiers used in the extended operation need not be listed
as values of this attribute.
+
Procedures for registering object identifiers used to discovery of
protocol mechanisms are detailed in BCP 64 [BCP64bis].
+
( 1.3.6.1.4.1.1466.101.120.7 NAME 'supportedExtension'
SYNTAX 1.3.6.1.4.1.1466.115.121.1.38
USAGE dSAOperation )
+
The OBJECT IDENTIFIER (1.3.6.1.4.1.1466.115.121.1.38) syntax is
defined in [Syntaxes].
+
5.1.5. 'supportedLDAPVersion'
+
The 'supportedLDAPVersion' attribute lists the versions of LDAP which
the server supports.
+
( 1.3.6.1.4.1.1466.101.120.15 NAME 'supportedLDAPVersion'
SYNTAX 1.3.6.1.4.1.1466.115.121.1.27
USAGE dSAOperation )
+
The INTEGER (1.3.6.1.4.1.1466.115.121.1.27) syntax are defined in
[Syntaxes].
+
5.1.6. 'supportedSASLMechanisms'
+
The 'supportedSASLMechanisms' attribute lists the SASL mechanisms
[SASL] which the server recognizes and/or supports [AuthMeth]. The
contents of this attribute may depend on the current session state.
If the server does not support any SASL mechanisms this attribute will
+
+
+
+
+Zeilenga LDAP Models [Page 39]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
not be present.
+
( 1.3.6.1.4.1.1466.101.120.14 NAME 'supportedSASLMechanisms'
SYNTAX 1.3.6.1.4.1.1466.115.121.1.15
USAGE dSAOperation )
+
The Directory String (1.3.6.1.4.1.1466.115.121.1.15) syntax is defined
in [Syntaxes].
-6. Other Considerations
-
-6.1. Preservation of User Information
-
- Syntaxes may be defined which have specific value and/or value form
+6. Other Considerations
-Zeilenga LDAP Models [Page 39]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
+6.1. Preservation of User Information
+ Syntaxes may be defined which have specific value and/or value form
(representation) preservation requirements. For example, a syntax
containing digitally signed data can mandate the server preserve both
the value and form of value presented to ensure signature is not
invalidated.
+
Where such requirements have not been explicitly stated, servers
SHOULD preserve the value of user information but MAY return the value
in a different form. And where a server is unable (or unwilling) to
an equivalent value (per Section 2.3) is returned.
+
6.2. Short Names
+
Short names, also known as descriptors, are used as more readable
aliases for object identifiers and are used to identify various schema
elements. However, it is not expected that LDAP implementations with
(stateOrProvinceName) might be displayed to a German-speaking user as
"Land".
+
The same short name might have different meaning in different
subschemas and, within a particular subschema, the same short name
might refer to different object identifiers each identifying a
different kind of schema element.
+
Implementations MUST be prepared that the same short name might be
used in a subschema to refer to the different kinds of schema
elements. That is, there might be an object class 'x-fubar' and an
attribute type 'x-fubar' in a subschema.
+
+
+
+Zeilenga LDAP Models [Page 40]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
Implementations MUST be prepared that the same short name might be
used in the different subschemas to refer to the different schema
elements. That is, there might be two matching rules 'x-fubar', each
in different subschemas.
+
Procedures for registering short names (descriptors) are detailed in
BCP 64 [BCP64bis].
+
6.3. Cache and Shadowing
+
Some servers may hold cache or shadow copies of entries, which can be
used to answer search and comparison queries, but will return
referrals or contact other servers if modification operations are
-
-
-
-Zeilenga LDAP Models [Page 40]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
requested. Servers that perform shadowing or caching MUST ensure that
they do not violate any access control constraints placed on the data
by the originating server.
+
7. Implementation Guidelines
+
7.1 Server Guidelines
+
Servers MUST recognize all names of attribute types and object classes
defined in this document but, unless stated otherwise, need not
support the associated functionality. Servers SHOULD recognize all
the names of attribute types and object classes defined in Section 3
and 4, respectively, of [Schema].
+
Servers MUST ensure that entries conform to user and system schema
rules or other data model constraints.
+
Servers MAY support DIT Content Rules. Servers MAY support DIT
Structure Rules and Name Forms.
+
Servers MAY support alias entries.
+
Servers MAY support the 'extensibleObject' object class.
+
Servers MAY support subentries. If so, they MUST do so in accordance
with [RFC3672]. Servers which do not support subentries SHOULD use
object entries to mimic subentries as detailed in Section 3.2.
+
Servers MAY implement additional schema elements. Servers SHOULD
provide definitions of all schema elements they support in subschema
(sub)entries.
+
+
+
+
+Zeilenga LDAP Models [Page 41]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
7.2 Client Guidelines
+
In the absence of prior agreements with servers, clients SHOULD NOT
assume that servers support any particular schema elements beyond
those referenced in Section 7.1. The client can retrieve subschema
information as described in Section 4.4.
+
Clients MUST NOT display nor attempt to decode as ASN.1, a value if
its syntax is not known. Clients MUST NOT assume the LDAP-specific
string encoding is restricted to a UTF-8 encoded string of Unicode
-Zeilenga LDAP Models [Page 41]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
8. Security Considerations
+
Attributes of directory entries are used to provide descriptive
information about the real-world objects they represent, which can be
people, organizations or devices. Most countries have privacy laws
regarding the publication of information about people.
+
General security considerations for accessing directory information
with LDAP are discussed in [Protocol] and [AuthMeth].
+
9. IANA Considerations
+
It is requested that the Internet Assigned Numbers Authority (IANA)
- update the LDAP descriptors registry as indicated the following
+ update the LDAP descriptors registry as indicated in the following
template:
+
Subject: Request for LDAP Descriptor Registration Update
Descriptor (short name): see comment
Object Identifier: see comment
Author/Change Controller: IESG
Comments:
+
The following descriptors (short names) should be added to
the registry.
+
NAME Type OID
------------------------ ---- -----------------
+
+
+
+
+Zeilenga LDAP Models [Page 42]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
governingStructureRule A 2.5.21.10
- structuralObjectClass A 2.5.21.5
+ structuralObjectClass A 2.5.21.9
+
The following descriptors (short names) should be updated to
refer to this RFC.
+
NAME Type OID
------------------------ ---- -----------------
alias O 2.5.6.1
creatorsName A 2.5.18.3
dITContentRules A 2.5.21.2
dITStructureRules A 2.5.21.1
-
-
-
-Zeilenga LDAP Models [Page 42]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
extensibleObject O 1.3.6.1.4.1.1466.101.120.111
ldapSyntaxes A 1.3.6.1.4.1.1466.101.120.16
matchingRuleUse A 2.5.21.8
top O 2.5.6.0
+
10. Acknowledgments
+
This document is based in part on RFC 2251 by M. Wahl, T. Howes, and
S. Kille; RFC 2252 by M. Wahl, A. Coulbeck, T. Howes, S. Kille; and
RFC 2556 by M. Wahl, all products of the IETF Access, Searching and
International Telephone Union (ITU). Additional text was borrowed
from RFC 2253 by M. Wahl, T. Howes, and S. Kille.
+
This document is a product of the IETF LDAP Revision (LDAPBIS) Working
Group.
+
+
+
+Zeilenga LDAP Models [Page 43]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
11. Editor's Address
+
Kurt Zeilenga
E-mail: <kurt@openldap.org>
+
12. References
+
+ [[Note to the RFC Editor: please replace the citation tags used in
+ referencing Internet-Drafts with tags of the form RFCnnnn.]]
+
+
+
12.1. Normative References
+
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14 (also RFC 2119), March 1997.
+
[RFC2234] Crocker, D. and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", RFC 2234, November 1997.
+ [RFC3629] Yergeau, F., "UTF-8, a transformation format of ISO
+ 10646", RFC 3629 (also STD 63), November 2003.
-Zeilenga LDAP Models [Page 43]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
- [RFC3639] Yergeau, F., "UTF-8, a transformation format of ISO
- 10646", RFC 3639 (also STD 63), November 2003.
[RFC3671] Zeilenga, K., "Collective Attributes in LDAP", RFC 3671,
December 2003.
+
[RFC3672] Zeilenga, K. and S. Legg, "Subentries in LDAP", RFC
3672, December 2003.
- [BCP64bis] Zeilenga, K., "IANA Considerations for LDAP", draft-
- ietf-ldapbis-bcp64-xx.txt, a work in progress.
+
+ [BCP64bis] Zeilenga, K., "IANA Considerations for LDAP",
+ draft-ietf-ldapbis-bcp64-xx.txt, a work in progress.
+
[Roadmap] Zeilenga, K. (editor), "LDAP: Technical Specification
Road Map", draft-ietf-ldapbis-roadmap-xx.txt, a work in
progress.
+
[Protocol] Sermersheim, J. (editor), "LDAP: The Protocol",
draft-ietf-ldapbis-protocol-xx.txt, a work in progress.
+
[AuthMeth] Harrison, R. (editor), "LDAP: Authentication Methods and
Connection Level Security Mechanisms",
draft-ietf-ldapbis-authmeth-xx.txt, a work in progress.
+
[Filters] Smith, M. (editor), LDAPbis WG, "LDAP: String
Representation of Search Filters",
draft-ietf-ldapbis-filter-xx.txt, a work in progress.
+
[LDAPDN] Zeilenga, K. (editor), "LDAP: String Representation of
+
+
+
+
+Zeilenga LDAP Models [Page 44]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
Distinguished Names", draft-ietf-ldapbis-dn-xx.txt, a
work in progress.
+
[LDAPURL] Smith, M. (editor), "LDAP: Uniform Resource Locator",
draft-ietf-ldapbis-url-xx.txt, a work in progress.
+
[SASL] Melnikov, A. (Editor), "Simple Authentication and
Security Layer (SASL)",
draft-ietf-sasl-rfc2222bis-xx.txt, a work in progress.
+
[Syntaxes] Legg, S. (editor), "LDAP: Syntaxes and Matching Rules",
draft-ietf-ldapbis-syntaxes-xx.txt, a work in progress.
+
[Schema] Dally, K. (editor), "LDAP: User Schema",
draft-ietf-ldapbis-user-schema-xx.txt, a work in
progress.
+
[Unicode] The Unicode Consortium, "The Unicode Standard, Version
3.2.0" is defined by "The Unicode Standard, Version 3.0"
(Reading, MA, Addison-Wesley, 2000. ISBN 0-201-61633-5),
-
-
-
-Zeilenga LDAP Models [Page 44]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
as amended by the "Unicode Standard Annex #27: Unicode
3.1" (http://www.unicode.org/reports/tr27/) and by the
"Unicode Standard Annex #28: Unicode 3.2"
(http://www.unicode.org/reports/tr28/).
+
[X.500] International Telecommunication Union -
Telecommunication Standardization Sector, "The Directory
-- Overview of concepts, models and services,"
X.500(1993) (also ISO/IEC 9594-1:1994).
+
[X.501] International Telecommunication Union -
Telecommunication Standardization Sector, "The Directory
-- Models," X.501(1993) (also ISO/IEC 9594-2:1994).
+
[X.680] International Telecommunication Union -
Telecommunication Standardization Sector, "Abstract
Syntax Notation One (ASN.1) - Specification of Basic
Notation", X.680(1997) (also ISO/IEC 8824-1:1998).
+
12.2. Informative References
+
None.
+
Appendix A. Changes
+
This appendix is non-normative.
+
+
+
+Zeilenga LDAP Models [Page 45]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
This document amounts to nearly a complete rewrite of portions of RFC
2251, RFC 2252, and RFC 2256. This rewrite was undertaken to improve
overall clarity of technical specification. This appendix provides a
portions of these documents.
+
A.1 Changes to RFC 2251
+
This document incorporates from RFC 2251 sections 3.2 and 3.4,
portions of Section 4 and 6 as summarized below.
+
A.1.1 Section 3.2 of RFC 2251
+
Section 3.2 of RFC 2251 provided a brief introduction to the X.500
data model, as used by LDAP. The previous specification relied on
-
-
-
-Zeilenga LDAP Models [Page 45]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
[X.501] but lacked clarity in how X.500 models are adapted for use by
LDAP. This document describes the X.500 data models, as used by LDAP
in greater detail, especially in areas where adaptation is needed.
+
Section 3.2.1 of RFC 2251 described an attribute as "a type with one
or more associated values." In LDAP, an attribute is better described
as an attribute description, a type with zero or more options, and one
or more associated values.
+
Section 3.2.2 of RFC 2251 mandated that subschema subentries contain
objectClasses and attributeTypes attributes, yet X.500(93) treats
these attributes as optional. While generally all implementations
attribute.
+
A.1.2 Section 3.4 of RFC 2251
+
Section 3.4 of RFC 2251 provided "Server-specific Data Requirements".
This material, with changes, was incorporated in Section 5.1 of this
document.
+
Changes:
+
+
+
+
+Zeilenga LDAP Models [Page 46]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
- Clarify that attributes of the root DSE are subject to "other
restrictions" in addition to access controls.
+
- Clarify that only recognized extended requests need to be enumerated
'supportedExtension'.
+
- Clarify that only recognized request controls need to be enumerated
'supportedControl'.
+
- Clarify that root DSE attributes are operational and, like other
operational attributes, will not be returned in search requests
unless requested by name.
+
- Clarify that not all root DSE attributes are user modifiable.
+
- Remove inconsistent text regarding handling of the
'subschemaSubentry' attribute within the root DSE. The previous
specification stated that the 'subschemaSubentry' attribute held in
the root DSE referred to "subschema entries (or subentries) known by
-
-
-
-Zeilenga LDAP Models [Page 46]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
this server." This is inconsistent with the attribute intended use
as well as its formal definition as a single valued attribute
[X.501]. It is also noted that a simple (possibly incomplete) list
available (see Section 4.4 of this document).
+
A.1.2 Section 4 of RFC 2251
+
Portions of Section 4 of RFC 2251 detailing aspects of the information
model used by LDAP were incorporated in this document, including:
+
- Restriction of distinguished values to attributes whose descriptions
- have no options (from Section 4.1.3).
+ have no options (from Section 4.1.3);
+
- Data model aspects of Attribute Types (from Section 4.1.4),
- Attribute Descriptions (from 4.1.4), Attribute (from 4.1.8),
- Matching Rule Identifier (from 4.1.9).
+ Attribute Descriptions (from 4.1.5), Attribute (from 4.1.8),
+ Matching Rule Identifier (from 4.1.9); and
+
- User schema requirements (from Section 4.1.6, 4.5.1, and 4.7).
+
+Clarifications to these portions include:
+
+
+ - Subtyping and AttributeDescriptions with options.
+
+
+
+
+
+Zeilenga LDAP Models [Page 47]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
A.1.3 Section 6 of RFC 2251
+
The Section 6.1 and the second paragraph of Section 6.2 of RFC 2251
where incorporated into this document.
+
A.2 Changes to RFC 2252
+
This document incorporates Sections 4, 5 and 7 from RFC 2252.
+
A.2.1 Section 4 of RFC 2252
+
The specification was updated to use Augmented BNF [RFC2234]. The
string representation of an OBJECT IDENTIFIER was tighten to
disallow leading zeros as described in RFC 2252 text.
+
The <descr> syntax was changed to disallow semicolon (U+003B)
characters to appear to be consistent its natural language
specification "descr is the syntactic representation of an object
descriptor, which consists of letters and digits, starting with a
letter." In a related change, the statement "an
AttributeDescription can be used as the value in a NAME part of an
-
-
-
-Zeilenga LDAP Models [Page 47]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
AttributeTypeDescription" was deleted. RFC 2252 provided no
specification of the semantics of attribute options appearing in
NAME fields.
+
RFC 2252 stated that the <descr> form of <oid> SHOULD be preferred
over the <numericoid> form. However, <descr> form can be ambiguous.
To address this issue, the imperative was replaced with a statement
available. Additionally, an expanded discussion of descriptor
issues is discussed in Section 6.2 (Short Names).
+
The ABNF for a quoted string (qdstring) was updated to reflect
support for the escaping mechanism described in 4.3 of RFC 2252.
+
A.2.2 Section 5 of RFC 2252
+
Definitions of operational attributes provided in Section 5 of RFC
2252 where incorporated into this document.
+
The 'namingContexts' description was clarified. A first-level DSA
should publish, in addition to other values, "" indicating the root
of the DIT.
+
+
+
+
+Zeilenga LDAP Models [Page 48]
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+
+
+
The 'altServer' description was clarified. It may hold any URI.
+
The 'supportedExtension' description was clarified. A server need
only list the OBJECT IDENTIFIERs associated with the extended
requests of the extended operations it recognizes.
+
The 'supportedControl' description was clarified. A server need
only list the OBJECT IDENTIFIERs associated with the request
controls it recognizes.
+
Descriptions for the 'structuralObjectClass' and
'governingStructureRule' operational attribute types were added.
+
A.2.3 Section 7 of RFC 2252
+
Section 7 of RFC 2252 provides definitions of the 'subschema' and
'extensibleObject' object classes. These definitions where
integrated into Section 4.2 and Section 4.3 of this document,
this document.
-
-
-Zeilenga LDAP Models [Page 48]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
The specification of 'extensibleObject' was clarified of how it
interacts with precluded attributes.
+
A.3 Changes to RFC 2256
+
This document incorporates Sections 5.1, 5.2, 7.1, and 7.2 of RFC
2256.
+
Section 5.1 of RFC 2256 provided the definition of the 'objectClass'
attribute type. This was integrated into Section 2.4.1 of this
document. The statement "One of the values is either 'top' or
'alias'" was replaced with statement that one of the values is 'top'
as entries belonging to 'alias' also belong to 'top'.
+
Section 5.2 of RFC 2256 provided the definition of the
'aliasedObjectName' attribute type. This was integrated into
Section 2.6.2 of this document.
+
Section 7.1 of RFC 2256 provided the definition of the 'top' object
class. This was integrated into Section 2.4.1 of this document.
+
Section 7.2 of RFC 2256 provided the definition of the 'alias'
object class. This was integrated into Section 2.6.1 of this
document.
-Intellectual Property Rights
-
- The IETF takes no position regarding the validity or scope of any
- intellectual property or other rights that might be claimed to pertain
- to the implementation or use of the technology described in this
- document or the extent to which any license under such rights might or
- might not be available; neither does it represent that it has made any
- effort to identify any such rights. Information on the IETF's
- procedures with respect to rights in standards-track and
- standards-related documentation can be found in BCP-11. Copies of
- claims of rights made available for publication and any assurances of
- licenses to be made available, or the result of an attempt made to
- obtain a general license or permission for the use of such proprietary
- rights by implementors or users of this specification can be obtained
- from the IETF Secretariat.
-
- The IETF invites any interested party to bring to its attention any
- copyrights, patents or patent applications, or other proprietary
- rights which may cover technology that may be required to practice
- this standard. Please address the information to the IETF Executive
-
-
Zeilenga LDAP Models [Page 49]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-models-10 15 February 2004
-
-
- Director.
-
-
-
-Full Copyright
-
- Copyright (C) The Internet Society (2004). All Rights Reserved.
-
- This document and translations of it may be copied and furnished to
- others, and derivative works that comment on or otherwise explain it
- or assist in its implementation may be prepared, copied, published and
- distributed, in whole or in part, without restriction of any kind,
- provided that the above copyright notice and this paragraph are
- included on all such copies and derivative works. However, this
- document itself may not be modified in any way, such as by removing
- the copyright notice or references to the Internet Society or other
- Internet organizations, except as needed for the purpose of
- developing Internet standards in which case the procedures for
- copyrights defined in the Internet Standards process must be followed,
- or as required to translate it into languages other than English.
-
-
+INTERNET-DRAFT draft-ietf-ldapbis-models-12 24 October 2004
+Intellectual Property Rights
+ The IETF takes no position regarding the validity or scope of any
+ Intellectual Property Rights or other rights that might be claimed to
+ pertain to the implementation or use of the technology described in
+ this document or the extent to which any license under such rights
+ might or might not be available; nor does it represent that it has
+ made any independent effort to identify any such rights. Information
+ on the procedures with respect to rights in RFC documents can be found
+ in BCP 78 and BCP 79.
+ Copies of IPR disclosures made to the IETF Secretariat and any
+ assurances of licenses to be made available, or the result of an
+ attempt made to obtain a general license or permission for the use of
+ such proprietary rights by implementers or users of this specification
+ can be obtained from the IETF on-line IPR repository at
+ http://www.ietf.org/ipr.
+ The IETF invites any interested party to bring to its attention any
+ copyrights, patents or patent applications, or other proprietary
+ rights that may cover technology that may be required to implement
+ this standard. Please address the information to the IETF at
+ ietf-ipr@ietf.org.
+Full Copyright
+ Copyright (C) The Internet Society (2004). This document is subject
+ to the rights, licenses and restrictions contained in BCP 78, and
+ except as set forth therein, the authors retain all their rights.
+ This document and the information contained herein are provided on an
+ "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
+ OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
+ ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
+ INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
+ INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
+ WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
-Zeilenga LDAP Models [Page 50]
-\f
+Zeilenga LDAP Models [Page 50]
\ No newline at end of file
-
Internet-Draft Editor: J. Sermersheim
Intended Category: Standard Track Novell, Inc
-Document: draft-ietf-ldapbis-protocol-26.txt Aug 2004
+Document: draft-ietf-ldapbis-protocol-27.txt Oct 2004
Obsoletes: RFCs 2251, 2830, 3771
Status of this Memo
This document is an Internet-Draft and is subject to all provisions
- of section 3 of RFC 3667. By submitting this Internet-Draft, each
+ of section 3 of RFC 3667. By submitting this Internet-Draft, each
author represents that any applicable patent or other IPR claims of
which he or she is aware have been or will be disclosed, and any of
which he or she become aware will be disclosed, in accordance with
RFC 3668.
Internet-Drafts are working documents of the Internet Engineering
- Task Force (IETF), its areas, and its working groups. Note that
- other groups may also distribute working documents as Internet-
- Drafts.
+ Task Force (IETF), its areas, and its working groups. Note that other
+ groups may also distribute working documents as Internet-Drafts.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
- time. It is inappropriate to use Internet-Drafts as reference
- material or to cite them other than as "work in progress."
+ time. It is inappropriate to use Internet-Drafts as reference
+ material or to cite them other than as "work in progress".
The list of current Internet-Drafts can be accessed at
- http://www.ietf.org/ietf/1id-abstracts.txt.
+ <http://www.ietf.org/ietf/1id-abstracts.txt>.
The list of Internet-Draft Shadow Directories can be accessed at
- http://www.ietf.org/shadow.html.
+ <http://www.ietf.org/shadow.html>.
+
+ This Internet-Draft will expire in February 2005.
Technical discussion of this document will take place on the IETF
LDAP Revision Working Group (LDAPbis) mailing list <ietf-
Copyright Notice
- Copyright (C) The Internet Society 2004.
+ Copyright (C) The Internet Society 2004. All Rights Reserved.
Abstract
elements are based on those described in the X.500 Directory Access
Protocol (DAP).
-
-Sermersheim Internet-Draft - Expires Feb 2005 Page 1
-\f
+Sermersheim Internet-Draft - Expires Apr 2005 Page 1
Lightweight Directory Access Protocol Version 3
+
Table of Contents
1. Introduction....................................................3
4.11. Abandon Operation...........................................32
4.12. Extended Operation..........................................32
4.13. IntermediateResponse Message................................34
- 4.13.1. Usage with LDAP ExtendedRequest and ExtendedResponse......35
+ 4.13.1. Usage with LDAP ExtendedRequest and ExtendedResponse......34
4.13.2. Usage with LDAP Request Controls..........................35
4.14. StartTLS Operation..........................................35
5. Protocol Encoding, Connection, and Transfer....................37
- 5.2. Protocol Encoding............................................38
+ 5.2. Protocol Encoding............................................37
5.3. Transmission Control Protocol (TCP)..........................38
- 6. Security Considerations........................................39
- 7. Acknowledgements...............................................40
+ 6. Security Considerations........................................38
+ 7. Acknowledgements...............................................39
8. Normative References...........................................40
- 9. Informative References.........................................42
+ 9. Informative References.........................................41
10. IANA Considerations...........................................42
- 11. Editor's Address..............................................43
- Appendix A - LDAP Result Codes....................................44
- A.1 Non-Error Result Codes........................................44
- A.2 Result Codes..................................................44
- Appendix B - Complete ASN.1 Definition............................49
- Appendix C - Changes..............................................55
- C.1 Changes made to RFC 2251:.....................................55
- C.2 Changes made to RFC 2830:.....................................60
- C.3 Changes made to RFC 3771:.....................................61
+ 11. Editor's Address..............................................42
+ Appendix A - LDAP Result Codes....................................43
+ A.1 Non-Error Result Codes........................................43
+ A.2 Result Codes..................................................43
+ Appendix B - Complete ASN.1 Definition............................48
+ Appendix C - Changes..............................................54
+ C.1 Changes made to RFC 2251:.....................................54
+ C.2 Changes made to RFC 2830:.....................................59
+ C.3 Changes made to RFC 3771:.....................................59
-
-Sermersheim Internet-Draft - Expires Feb 2005 Page 2
-\f
+Sermersheim Internet-Draft - Expires Apr 2005 Page 2
Lightweight Directory Access Protocol Version 3
+
1. Introduction
The Directory is "a collection of open systems cooperating to provide
"SHOULD", "SHOULD NOT", "RECOMMENDED", and "MAY" in this document are
to be interpreted as described in [Keyword].
+ Character names in this document use the notation for code points and
+ names from the Unicode Standard [Unicode]. For example, the letter
+ "a" may be represented as either <U+0061> or <LATIN SMALL LETTER A>.
+
+ Note: a glossary of terms used in Unicode can be found in [Glossary].
+ Information on the Unicode character encoding model can be found in
+ [CharModel].
+
+
+Sermersheim Internet-Draft - Expires Apr 2005 Page 3
+ Lightweight Directory Access Protocol Version 3
+
The term "connection" refers to the underlying transport service used
to carry the protocol exchange.
- The term "LDAP exchange" refers to application layer where LDAP PDUs
- are exchanged between protocol peers.
+ The term "LDAP exchange" refers to the layer where LDAP PDUs are
+ exchanged between protocol peers.
The term "TLS layer" refers to a layer inserted between the
connection and the LDAP exchange that utilizes Transport Layer
Security ([TLS]) to protect the exchange of LDAP PDUs.
-
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- Lightweight Directory Access Protocol Version 3
-
The term "SASL layer" refers to a layer inserted between the
connection and the LDAP exchange that utilizes Simple Authentication
and Security Layer ([SASL]) to protect the exchange of LDAP PDUs.
See the table in Section 5 for an illustration of these four terms.
-
- The term "TLS-protected LDAP exchange" refers to an LDAP exchange
- protected by a TLS-layer.
-
- The term "association" refers to the association of the LDAP exchange
- and its current authentication and authorization state.
-
- Character names in this document use the notation for code points and
- names from the Unicode Standard [Unicode]. For example, the letter
- "a" may be represented as either <U+0061> or <LATIN SMALL LETTER A>.
-
- Note: a glossary of terms used in Unicode can be found in [Glossary].
- Information on the Unicode character encoding model can be found in
- [CharModel].
-
+
3. Protocol Model
3.1 Operation and LDAP Exchange Relationship
-
-
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- Lightweight Directory Access Protocol Version 3
-
Protocol operations are tied to an LDAP exchange. When the connection
is closed, any uncompleted operations tied to the LDAP exchange are,
when possible, abandoned, and when not possible, completed without
transmission of the response. Also, when the connection is closed,
the client MUST NOT assume that any uncompleted update operations
tied to the LDAP exchange have succeeded or failed.
+
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+
4. Elements of Protocol
bindResponse BindResponse,
unbindRequest UnbindRequest,
searchRequest SearchRequest,
-
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- Lightweight Directory Access Protocol Version 3
-
searchResEntry SearchResultEntry,
searchResDone SearchResultDone,
searchResRef SearchResultReference,
modifyRequest ModifyRequest,
modifyResponse ModifyResponse,
addRequest AddRequest,
+
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+ Lightweight Directory Access Protocol Version 3
+
addResponse AddResponse,
delRequest DelRequest,
delResponse DelResponse,
messageID value of the corresponding request LDAPMessage.
The message ID of a request MUST have a non-zero value different from
- the values of any other uncompleted requests in the LDAP association
- of which this message is a part. The zero value is reserved for the
- unsolicited notification message.
-
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- Lightweight Directory Access Protocol Version 3
-
+ the the messageID of any other uncompleted requests in the LDAP
+ exchange. The zero value is reserved for the unsolicited notification
+ message.
Typical clients increment a counter for each request.
A client MUST NOT send a request with the same message ID as an
- earlier request on the same LDAP association unless it can be
- determined that the server is no longer servicing the earlier request
- (e.g. after the final response is received, or a subsequent bind
+ earlier request in the same LDAP exchange unless it can be determined
+ that the server is no longer servicing the earlier request (e.g.
+
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+
+ after the final response is received, or a subsequent bind
completes). Otherwise the behavior is undefined. For this purpose,
note that abandon and abandoned operations do not send responses.
4.1.4. Attribute Descriptions
-
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- Lightweight Directory Access Protocol Version 3
-
The definition and encoding rules for attribute descriptions are
defined in Section 2.5 of [Models]. Briefly, an attribute description
is an attribute type and zero or more options.
AttributeDescription ::= LDAPString
+
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+ Lightweight Directory Access Protocol Version 3
+
-- Constrained to <attributedescription>
-- [Models]
The syntax of the AssertionValue depends on the context of the LDAP
operation being performed. For example, the syntax of the EQUALITY
matching rule for an attribute is used when performing a Compare
-
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- Lightweight Directory Access Protocol Version 3
-
operation. Often this is the same syntax used for values of the
attribute type, but in some cases the assertion syntax differs from
the value syntax. See objectIdentiferFirstComponentMatch in
[Syntaxes] for an example.
+
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+ Lightweight Directory Access Protocol Version 3
+
4.1.7. Attribute and PartialAttribute
Attributes and partial attributes consist of an attribute description
compareTrue (6),
authMethodNotSupported (7),
strongAuthRequired (8),
-
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- Lightweight Directory Access Protocol Version 3
-
-- 9 reserved --
referral (10),
adminLimitExceeded (11),
unavailableCriticalExtension (12),
confidentialityRequired (13),
saslBindInProgress (14),
+
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+ Lightweight Directory Access Protocol Version 3
+
noSuchAttribute (16),
undefinedAttributeType (17),
inappropriateMatching (18),
readable (terminal control and page formatting characters should be
avoided) diagnostic message. As this diagnostic message is not
standardized, implementations MUST NOT rely on the values returned.
-
-
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- Lightweight Directory Access Protocol Version 3
-
If the server chooses not to return a textual diagnostic, the
diagnosticMessage field MUST be empty.
For certain result codes (typically, but not restricted to
noSuchObject, aliasProblem, invalidDNSyntax and
- aliasDereferencingProblem), the matchedDN field is set to the name of
- the lowest entry (object or alias) in the Directory that was matched.
- If no aliases were dereferenced while attempting to locate the entry,
- this will be a truncated form of the name provided, or if aliases
- were dereferenced, of the resulting name, as defined in Section 12.5
- of [X.511]. Otherwise the matchedDN field is empty.
+ aliasDereferencingProblem), the matchedDN field is set (subject to
+ access controls) to the name of the last entry (object or alias) used
+
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+ Lightweight Directory Access Protocol Version 3
+
+ in finding the target (or base) object. If no aliases were
+ dereferenced while attempting to locate the entry, this will be a
+ truncated form of the name provided or if aliases were dereferenced,
+ of the resulting name, as defined in Section 12.5 of [X.511].
+ Otherwise the matchedDN field is empty.
4.1.10. Referral
server for the same request with the same target entry name, scope
and filter. Some implementations use a counter that is incremented
each time referral handling occurs for an operation, and these kinds
-
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- Lightweight Directory Access Protocol Version 3
-
of implementations MUST be able to handle at least ten nested
referrals between the root and a leaf entry.
A URI for a server implementing LDAP and accessible via [TCP]/[IP]
(v4 or v6) is written as an LDAP URL according to [LDAPURL].
+
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+ Lightweight Directory Access Protocol Version 3
+
When an LDAP URL is used, the following instructions are followed:
- If an alias was dereferenced, the <dn> part of the URL MUST be
Controls sent by clients are termed 'request controls' and those sent
by servers are termed 'response controls'.
-
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- Lightweight Directory Access Protocol Version 3
-
Controls ::= SEQUENCE OF control Control
Control ::= SEQUENCE {
controlType LDAPOID,
criticality BOOLEAN DEFAULT FALSE,
controlValue OCTET STRING OPTIONAL }
+
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+ Lightweight Directory Access Protocol Version 3
+
The controlType field is the dotted-decimal representation of an
OBJECT IDENTIFIER which uniquely identifies the control. This
combinations, if specified, are generally found in the control
specification most recently published. When a combination of controls
is encountered whose semantics are invalid, not specified (or not
-
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- Lightweight Directory Access Protocol Version 3
-
known), the message is considered to be not well-formed, thus the
operation fails with protocolError. Additionally, unless order-
dependent semantics are given in a specification, the order of a
combination of controls in the SEQUENCE is ignored. Where the order
is to be ignored but cannot be ignored by the server, the message is
+
+
+
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+ Lightweight Directory Access Protocol Version 3
+
considered not well-formed and the operation fails with
protocolError.
credentials OCTET STRING OPTIONAL }
Fields of the Bind Request are:
+
+ - version: A version number indicating the version of the protocol
+ to be used for the LDAP exchange. This document describes version
+ 3 of the protocol. There is no version negotiation. The client
+ sets this field to the version it desires. If the server does not
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Lightweight Directory Access Protocol Version 3
+ support the specified version, it MUST respond with protocolError
+ in the resultCode field of the BindResponse.
- - version: A version number indicating the version of the protocol
- to be used in this LDAP association. This document describes
- version 3 of the protocol. There is no version negotiation. The
- client sets this field to the version it desires. If the server
- does not support the specified version, it MUST respond with
- protocolError in the resultCode field of the BindResponse.
-
- - name: The name of the Directory object that the client wishes to
- bind as. This field may take on a null value (a zero length
- string) for the purposes of anonymous binds ([AuthMeth] Section
- 5.1) or when using Simple Authentication and Security Layer [SASL]
- authentication ([AuthMeth] Section 3.3.2). Where the server
- attempts to locate the named object, it SHALL NOT perform alias
- dereferencing.
+ - name: If not empty, the name of the Directory object that the
+ client wishes to bind as. This field may take on a null value (a
+ zero length string) for the purposes of anonymous binds
+ ([AuthMeth] Section 5.1) or when using Simple Authentication and
+ Security Layer [SASL] authentication ([AuthMeth] Section 3.3.2).
+ Where the server attempts to locate the named object, it SHALL NOT
+ perform alias dereferencing.
- authentication: information used in authentication. This type is
extensible as defined in Section 3.7 of [LDAPIANA]. Servers that
If the client did not bind before sending a request and receives an
operationsError to that request, it may then send a Bind Request. If
-
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- Lightweight Directory Access Protocol Version 3
-
this also fails or the client chooses not to bind on the existing
LDAP exchange, it may close the connection, reopen it and begin again
by first sending a PDU with a Bind Request. This will aid in
interoperating with servers implementing other versions of LDAP.
+
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+ Lightweight Directory Access Protocol Version 3
+
Clients may send multiple Bind Requests on an LDAP exchange to change
the authentication and/or security associations or to complete a
multi-stage bind process. Authentication from earlier binds is
The serverSaslCreds field is used as part of a SASL-defined bind
mechanism to allow the client to authenticate the server to which it
is communicating, or to perform "challenge-response" authentication.
-
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- Lightweight Directory Access Protocol Version 3
-
If the client bound with the simple choice, or the SASL mechanism
does not require the server to return information to the client, then
this field SHALL NOT be included in the BindResponse.
+
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+ Lightweight Directory Access Protocol Version 3
+
4.3. Unbind Operation
- The function of the Unbind Operation is to terminate an LDAP
- association and close the connection. The Unbind operation is not the
- antithesis of the Bind operation as the name implies. The naming of
- these operations is historical. The Unbind operation should be
- thought of as the "quit" operation.
+ The function of the Unbind Operation is to terminate an LDAP exchange
+ and close the connection. The Unbind operation is not the antithesis
+ of the Bind operation as the name implies. The naming of these
+ operations is historical. The Unbind operation should be thought of
+ as the "quit" operation.
The Unbind Operation is defined as follows:
The Unbind Operation has no response defined. Upon transmission of
the UnbindRequest, each protocol peer is to consider the LDAP
- association terminated, MUST cease transmission of messages to the
- other peer, and MUST close the connection. Uncompleted operations are
+ exchange terminated, MUST cease transmission of messages to the other
+ peer, and MUST close the connection. Uncompleted operations are
handled as specified in Section 5.1.
4.4.1. Notice of Disconnection
-
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- Lightweight Directory Access Protocol Version 3
-
This notification may be used by the server to advise the client that
the server is about to close the connection due to an error
condition. This notification is intended to assist clients in
distinguishing between an error condition and a transient network
+
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+ Lightweight Directory Access Protocol Version 3
+
failure. Note that this notification is not a response to an unbind
requested by the client. Uncompleted operations are handled as
specified in Section 5.1.
is absent, and the resultCode is used to indicate the reason for the
disconnection.
- The following result codes have these meanings when used in this
- notification:
-
- - protocolError: The server has received data from the client in
- which the LDAPMessage structure could not be parsed.
-
- - strongAuthRequired: The server has detected that an established
- security association between the client and server has
- unexpectedly failed or been compromised, or that the server now
- requires the client to authenticate using a strong(er) mechanism.
-
- - unavailable: This server will stop accepting new connections and
- operations on all existing LDAP exchanges, and be unavailable for
- an extended period of time. The client may make use of an
- alternative server.
-
Upon transmission of the Notice of Disconnection, the server is to
- consider the LDAP association terminated, MUST cease transmission of
+ consider the LDAP exchange terminated, MUST cease transmission of
messages to the client, and MUST close the connection.
singleLevel (1),
wholeSubtree (2) },
derefAliases ENUMERATED {
-
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- Lightweight Directory Access Protocol Version 3
-
neverDerefAliases (0),
derefInSearching (1),
derefFindingBaseObj (2),
-- <attributeSelector> below
Filter ::= CHOICE {
- and [0] SET SIZE (1..MAX) OF filter Filter,
- or [1] SET SIZE (1..MAX) OF filter Filter,
+ and [0] SET OF filter Filter,
+ or [1] SET OF filter Filter,
not [2] Filter,
equalityMatch [3] AttributeValueAssertion,
substrings [4] SubstringFilter,
greaterOrEqual [5] AttributeValueAssertion,
+
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+ Lightweight Directory Access Protocol Version 3
+
lessOrEqual [6] AttributeValueAssertion,
present [7] AttributeDescription,
approxMatch [8] AttributeValueAssertion,
singleLevel: The scope is constrained to the immediate
subordinates of the entry named by baseObject.
-
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- Lightweight Directory Access Protocol Version 3
-
wholeSubtree: the scope is constrained to the entry named by
the baseObject, and all its subordinates.
also dereferenced. Servers SHOULD eliminate duplicate entries
that arise due to alias dereferencing while searching.
+
+
+
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+ Lightweight Directory Access Protocol Version 3
+
derefFindingBaseObj: Dereference aliases in locating the base
object of the search, but not when searching subordinates of
the base object.
The 'and', 'or' and 'not' choices can be used to form combinations
of filters. At least one filter element MUST be present in an
'and' or 'or' choice. The others match against individual
-
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- Lightweight Directory Access Protocol Version 3
-
attribute values of entries in the scope of the search.
(Implementor's note: the 'not' filter is an example of a tagged
choice in an implicitly-tagged module. In BER this is treated as
one filter is TRUE, and Undefined otherwise. A filter of the 'not'
choice is TRUE if the filter being negated is FALSE, FALSE if it
is TRUE, and Undefined if it is Undefined.
+
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+ Lightweight Directory Access Protocol Version 3
+
The present match evaluates to TRUE where there is an attribute or
subtype of the specified attribute description present in an
match, etc.) returns TRUE. If an item matches for equality, it
also satisfies an approximate match. If approximate matching is
not supported for the attribute, this filter item should be
-
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- Lightweight Directory Access Protocol Version 3
-
treated as an equalityMatch.
An extensibleMatch filter item is evaluated as follows:
If the type field is present and the matchingRule is present,
the matchValue is compared against entry attributes of the
specified type. In this case, the matchingRule MUST be one
+
+
+
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+ Lightweight Directory Access Protocol Version 3
+
suitable for use with the specified type (see [Syntaxes]),
otherwise the filter item is Undefined.
another applies to entries and dn attributes as well.
A filter item evaluates to Undefined when the server would not be
- able to determine whether the assertion value matches an entry. If
- an attribute description in an equalityMatch, substrings,
- greaterOrEqual, lessOrEqual, approxMatch or extensibleMatch filter
- is not recognized by the server, a MatchingRuleId in the
- extensibleMatch is not recognized by the server, the assertion
- value is invalid, or the type of filtering requested is not
- implemented, then the filter is Undefined. Thus for example if a
- server did not recognize the attribute type shoeSize, a filter of
- (shoeSize=*) would evaluate to FALSE, and the filters
- (shoeSize=12), (shoeSize>=12) and (shoeSize<=12) would evaluate to
- Undefined.
+ able to determine whether the assertion value matches an entry.
+ Examples include:
+
+ - An attribute description in an equalityMatch, substrings,
+ greaterOrEqual, lessOrEqual, approxMatch or extensibleMatch
+ filter is not recognized by the server.
+
+ - The attribute type does not define the appropriate matching
+ rule.
+
+ - A MatchingRuleId in the extensibleMatch is not recognized by
+ the server or is not valid for the attribute type.
+
+ - The type of filtering requested is not implemented.
+
+ - The assertion value is invalid.
+
+ For example, if a server did not recognize the attribute type
+ shoeSize, a filter of (shoeSize=*) would evaluate to FALSE, and
+ the filters (shoeSize=12), (shoeSize>=12) and (shoeSize<=12) would
+ each evaluate to Undefined.
Servers MUST NOT return errors if attribute descriptions or
matching rule ids are not recognized, assertion values are
this field are constrained to the following Augmented Backus-Naur
Form ([ABNF]):
-
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- Lightweight Directory Access Protocol Version 3
-
attributeSelector = attributedescription / selectorpecial
selectorspecial = noattrs / alluserattrs
alluserattrs = %x2A ; asterisk ("*")
+
+
+
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+ Lightweight Directory Access Protocol Version 3
+
The <attributedescription> production is defined in Section 2.5 of
[Models].
although it may choose to do so, and if it does, it must provide the
same semantics as the X.500 search operation.
-
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- Lightweight Directory Access Protocol Version 3
-
4.5.2. Search Result
messages, followed by a single searchResultDone message.
SearchResultEntry ::= [APPLICATION 4] SEQUENCE {
+
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+ Lightweight Directory Access Protocol Version 3
+
objectName LDAPDN,
attributes PartialAttributeList }
4.5.3. Continuation References in the Search Result
-
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- Lightweight Directory Access Protocol Version 3
-
If the server was able to locate the entry referred to by the
baseObject but was unable to search one or more non-local entries,
the server may return one or more SearchResultReference entries, each
operation. A server MUST NOT return any SearchResultReference if it
has not located the baseObject and thus has not searched any entries;
in this case it would return a SearchResultDone containing either a
+
+
+
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+ Lightweight Directory Access Protocol Version 3
+
referral or noSuchObject result code (depending on the server's
knowledge of the entry named in the baseObject).
In order to complete the search, the client issues a new search
operation for each SearchResultReference that is returned. Note that
the abandon operation described in Section 4.11 applies only to a
- particular operation sent on an association between a client and
+ particular operation sent on the LDAP exchange between a client and
server. The client must abandon subsequent search operations it
wishes to individually.
- If the originating search scope was singleLevel, the <scope> part
of the URL will be "base".
-
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-\f
- Lightweight Directory Access Protocol Version 3
-
- - it is RECOMMENDED that the <scope> part be present to avoid
+ - It is RECOMMENDED that the <scope> part be present to avoid
ambiguity.
- Other aspects of the new search request may be the same as or
different from the search request which generated the
SearchResultReference.
+
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+ Lightweight Directory Access Protocol Version 3
+
- The name of an unexplored subtree in a SearchResultReference need
not be subordinate to the base object.
SearchResultEntry for CN=Manager,DC=Example,DC=NET
SearchResultReference {
-
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- Lightweight Directory Access Protocol Version 3
-
ldap://hostb/OU=People,DC=Example,DC=NET??base
ldap://hostc/OU=People,DC=Example,DC=NET??base }
SearchResultReference {
ldap://hostd/OU=Roles,DC=Example,DC=NET??base }
SearchResultDone (success)
+
+
+
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+ Lightweight Directory Access Protocol Version 3
+
If the contacted server does not hold the base object for the search,
but has knowledge of its possible location, then it may return a
referral to the client. In this case, if the client requests a
add: add values listed to the modification attribute,
creating the attribute if necessary;
-
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- Lightweight Directory Access Protocol Version 3
-
delete: delete values listed from the modification attribute,
removing the entire attribute if no values are listed, or if
all current values of the attribute are listed for deletion;
+
+
+
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+ Lightweight Directory Access Protocol Version 3
+
replace: replace all existing values of the modification
attribute with the new values listed, creating the attribute
if it did not already exist. A replace with no value will
been performed if the Modify Response received indicates any sort of
error, and that all requested modifications have been performed if
the Modify Response indicates successful completion of the Modify
- Operation. If the association changes or the connection fails,
- whether the modification occurred or not is indeterminate.
+ Operation. The result of the modification is indeterminate if the
+ Modify Response is not received (e.g. the LDA exchange is terminated
+ or the Modify Operation is abandoned).
The Modify Operation cannot be used to remove from an entry any of
its distinguished values, i.e. those values which form the entry's
AddRequest ::= [APPLICATION 8] SEQUENCE {
entry LDAPDN,
attributes AttributeList }
-
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-\f
- Lightweight Directory Access Protocol Version 3
-
AttributeList ::= SEQUENCE OF attribute Attribute
Fields of the Add Request are:
+
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+ Lightweight Directory Access Protocol Version 3
+
- entry: the name of the entry to be added. The server SHALL NOT
dereference any aliases in locating the entry to be added.
Only leaf entries (those with no subordinate entries) can be deleted
with this operation.
-
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-\f
- Lightweight Directory Access Protocol Version 3
-
Upon receipt of a Delete Request, a server will attempt to perform
the entry removal requested and return the result in the Delete
Response defined as follows:
+
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+ Lightweight Directory Access Protocol Version 3
+
DelResponse ::= [APPLICATION 11] LDAPResult
Smith,c=US>, the newrdn field was <cn=John Cougar Smith>, and the
newSuperior field was absent, then this operation would attempt to
rename the entry to be <cn=John Cougar Smith,c=US>. If there was
-
-
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-\f
- Lightweight Directory Access Protocol Version 3
-
already an entry with that name, the operation would fail with the
entryAlreadyExists result code.
The object named in newSuperior MUST exist. For example, if the
client attempted to add <CN=JS,DC=Example,DC=NET>, the
+
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+ Lightweight Directory Access Protocol Version 3
+
<DC=Example,DC=NET> entry did not exist, and the <DC=NET> entry did
exist, then the server would return the noSuchObject result code with
the matchedDN field containing <DC=NET>.
the ava field matches a value of the attribute or subtype according
to the attribute's EQUALITY matching rule. compareFalse indicates
that the assertion value in the ava field and the values of the
-
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-\f
- Lightweight Directory Access Protocol Version 3
-
attribute or subtype did not match. Other result codes indicate
either that the result of the comparison was Undefined (Section
4.5.1), or that some error occurred.
+
+
+
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+ Lightweight Directory Access Protocol Version 3
+
Note that some directory systems may establish access controls which
permit the values of certain attributes (such as userPassword) to be
compared but not interrogated by other means.
AbandonRequest ::= [APPLICATION 16] MessageID
The MessageID is that of an operation which was requested earlier in
- this LDAP association. The abandon request itself has its own
- MessageID. This is distinct from the MessageID of the earlier
- operation being abandoned.
+ this LDAP exchange. The abandon request itself has its own MessageID.
+ This is distinct from the MessageID of the earlier operation being
+ abandoned.
There is no response defined in the Abandon operation. Upon receipt
of an AbandonRequest, the server MAY abandon the operation identified
4.12. Extended Operation
-
-
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-\f
- Lightweight Directory Access Protocol Version 3
-
The extended operation allows additional operations to be defined for
services not already available in the protocol. For example, to add
operations to install transport layer security (see Section 4.14).
+
+
+
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+ Lightweight Directory Access Protocol Version 3
+
The extended operation allows clients to make requests and receive
responses with predefined syntaxes and semantics. These may be
defined in RFCs or be private to particular implementations.
Section 4.
Servers list the requestName of Extended Requests they recognize in
- the ' supportedExtension ' attribute in the root DSE (Section 5.1 of
+ the 'supportedExtension' attribute in the root DSE (Section 5.1 of
[Models]).
Extended operations may be specified in other documents. The
- the OBJECT IDENTIFIER assigned to the requestName,
-
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- Lightweight Directory Access Protocol Version 3
-
- the OBJECT IDENTIFIER (if any) assigned to the responseName (note
that the same OBJECT IDENTIFIER my be used for both the
requestName and responseName),
+
+Sermersheim Internet-Draft - Expires Apr 2005 Page 33
+ Lightweight Directory Access Protocol Version 3
+
- the format of the contents of the requestValue and responseValue
(if any), and
IntermediateResponse messages SHALL identify those types using unique
responseName values (note that one of these may specify no value).
-
-
-
-Sermersheim Internet-Draft - Expires Feb 2005 Page 34
-\f
- Lightweight Directory Access Protocol Version 3
-
Sections 4.13.1 and 4.13.2 describe additional requirements on the
inclusion of responseName and responseValue in IntermediateResponse
messages.
4.13.1. Usage with LDAP ExtendedRequest and ExtendedResponse
+
+Sermersheim Internet-Draft - Expires Apr 2005 Page 34
+ Lightweight Directory Access Protocol Version 3
+
A single-request/multiple-response operation may be defined using a
single ExtendedRequest message to solicit zero or more
4.14. StartTLS Operation
- The Start Transport Layer Security (StartTLS) operation provides the
- ability to establish a TLS-protected LDAP exchange. The StartTLS
- operation is defined using the extended operation mechanism described
- in Section 4.12.
+ The Start Transport Layer Security (StartTLS) operationÆs purpose is
+ to initiate installation of a TLS layer. The StartTLS operation is
+ defined using the extended operation mechanism described in Section
+ 4.12.
4.14.1. StartTLS Request
this request until it receives a StartTLS extended response and, in
the case of a successful response, completes TLS negotiations.
+ Sequencing problems (particularly those detailed in Section 3.1.1 of
+ [AuthMeth] result in an operationsError being returned in the
+ resultCode.
+ If the server does not support TLS (whether by design or by current
+ configuration), it returns the protocolError resultCode as described
+ in Section 4.12.
-Sermersheim Internet-Draft - Expires Feb 2005 Page 35
-\f
+Sermersheim Internet-Draft - Expires Apr 2005 Page 35
Lightweight Directory Access Protocol Version 3
+
+
4.14.2. StartTLS Response
When a StartTLS request is made, servers supporting the operation
responseName, if present, is also "1.3.6.1.4.1.1466.20037". The
responseValue is absent.
- The server provides a resultCode field to either success or one of
- the other values outlined in Section 4.14.2.2.
-
-
-4.14.2.1. "Success" Response
+ If the server is willing and able to negotiate TLS, it returns a
+ success resultCode. Refer to Section 4 of [AuthMeth] for details.
- If the StartTLS Response contains a resultCode of success, this
- indicates that the server is willing and able to negotiate TLS. Refer
- to Section 4 of [AuthMeth] for details.
-
-
-4.14.2.2. Response other than "success"
-
- If the ExtendedResponse contains a result code other than success,
- this indicates that the server is unwilling or unable to negotiate
- TLS. The following result codes have these meanings for this
- operation:
-
- - operationsError: operations sequencing incorrect; e.g. TLS is
- already established.
-
- - protocolError: TLS is not supported or incorrect PDU structure.
-
- - unavailable: Some major problem with TLS, or the server is
- shutting down.
-
- The server MUST return operationsError if the client violates any of
- the StartTLS extended operation sequencing requirements described in
- Section 4 of [AuthMeth].
-
- If the server does not support TLS (whether by design or by current
- configuration), it MUST return the protocolError resultCode. In this
- event, the client may proceed with any LDAP operation, or it may
- close the connection.
-
- The server MUST return unavailable if it supports TLS but cannot
- install the TLS layer for some reason, e.g. the certificate server
- not responding, it cannot contact its TLS implementation, or if the
- server is in process of shutting down. The client may retry the
- StartTLS operation, or it may proceed with any other LDAP operation,
- or it may close the connection.
+ If the server is otherwise unwilling or unable to perform this
+ operation, the server is to return an appropriate result code
+ indicating the nature of the problem. For example, if the TLS
+ subsystem is not presently available, the server may return indicate
+ so by returning the unavailable resultCode.
4.14.3. Removal of the TLS Layer
-
-
-Sermersheim Internet-Draft - Expires Feb 2005 Page 36
-\f
- Lightweight Directory Access Protocol Version 3
-
Two forms of TLS layer removal -- graceful and abrupt -- are
provided. These do not involve LDAP PDUs, but are preformed at the
underlying layers.
After the TLS layer has been removed, the server MUST NOT send
responses to any request message received before the TLS closure
+
+Sermersheim Internet-Draft - Expires Apr 2005 Page 36
+ Lightweight Directory Access Protocol Version 3
+
alert. Thus, clients wishing to receive responses to messages sent
while the TLS layer is intact MUST wait for those message responses
before sending the TLS closure alert.
5.3. This service is generally applicable to applications providing
or consuming X.500-based directory services on the Internet. This
specification was generally written with the TCP mapping in mind.
-
-Sermersheim Internet-Draft - Expires Feb 2005 Page 37
-\f
- Lightweight Directory Access Protocol Version 3
-
Specifications detailing other mappings may encounter various
obstacles.
This table illustrates the relationship between the different layers
involved in an exchange between two protocol peers:
-
+
+---------------+
| LDAP exchange |
+---------------+ > LDAP PDUs
- Only the definite form of length encoding is used.
+
+Sermersheim Internet-Draft - Expires Apr 2005 Page 37
+ Lightweight Directory Access Protocol Version 3
+
- OCTET STRING values are encoded in the primitive form only.
- If the value of a BOOLEAN type is true, the encoding of the value
is recommended that server implementations running over the TCP
provide a protocol listener on the Internet Assigned Numbers
Authority (IANA)-assigned LDAP port, 389 [PortReg]. Servers may
-
-Sermersheim Internet-Draft - Expires Feb 2005 Page 38
-\f
- Lightweight Directory Access Protocol Version 3
-
instead provide a listener on a different port number. Clients MUST
support contacting servers on any valid TCP port.
referral fields of the bind response nor of any information contained
in controls attached to bind request or responses. Thus information
contained in these fields SHOULD NOT be relied on unless otherwise
+
+Sermersheim Internet-Draft - Expires Apr 2005 Page 38
+ Lightweight Directory Access Protocol Version 3
+
protected (such as by establishing protections at the transport
- layer).
-
- Server implementors should plan for the possibility of an identity in
- and association being deleted, renamed, or modified, and take
- appropriate actions to prevent insecure side effects. Likewise,
- server implementors should plan for the possibility of an associated
- identity's credentials becoming invalid, or an identity's privileges
- being changed. The ways in which these issues are addressed are
- application and/or implementation specific.
+ layer).
+
+ Server implementors should plan for the possibility of (protocol or
+ external) events which alter the information used to establish
+ security factors (e.g., credentials, authorization identities, access
+ controls) during the course of the LDAP exchange, and even during the
+ performance of a particular operation, and should take steps to avoid
+ insecure side effects of these changes. The ways in which these
+ issues are addressed are application and/or implementation specific.
Implementations which cache attributes and entries obtained via LDAP
MUST ensure that access controls are maintained if that information
application to inject such referrals into the data stream in an
attempt to redirect a client to a rogue server. Clients are advised
to be aware of this, and possibly reject referrals when
-
-Sermersheim Internet-Draft - Expires Feb 2005 Page 39
-\f
- Lightweight Directory Access Protocol Version 3
-
confidentiality measures are not in place. Clients are advised to
reject referrals from the StartTLS operation.
the directory which is subject to access and other administrative
controls. Server implementations should restrict access to protected
information equally under both normal and error conditions.
-
-
+
Protocol peers MUST be prepared to handle invalid and arbitrary
length protocol encodings. Invalid protocol encodings include: BER
encoding exceptions, format string and UTF-8 encoding exceptions,
It is also based on RFC 3771 by Roger Harrison, and Kurt Zeilenga.
RFC 3771 was an individual submission to the IETF.
- This document is a product of the LDAPBIS Working Group. Significant
- contributors of technical review and content include Kurt Zeilenga,
- Steven Legg, and Hallvard Furuseth.
+
+Sermersheim Internet-Draft - Expires Apr 2005 Page 39
+ Lightweight Directory Access Protocol Version 3
+
+ This document is a product of the IETF LDAPBIS Working Group.
+ Significant contributors of technical review and content include Kurt
+ Zeilenga, Steven Legg, and Hallvard Furuseth.
8. Normative References
[ABNF] Crocker, D. and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", RFC 2234, November 1997.
-
-Sermersheim Internet-Draft - Expires Feb 2005 Page 40
-\f
- Lightweight Directory Access Protocol Version 3
-
[ASN.1] ITU-T Recommendation X.680 (07/2002) | ISO/IEC 8824-1:2002
"Information Technology - Abstract Syntax Notation One
[SASL] Melnikov, A., "Simple Authentication and Security Layer",
draft-ietf-sasl-rfc2222bis-xx.txt (a work in progress).
+
+
+
+Sermersheim Internet-Draft - Expires Apr 2005 Page 40
+ Lightweight Directory Access Protocol Version 3
+
[SASLPrep] Zeilenga, K., "Stringprep profile for user names and
passwords", draft-ietf-sasl-saslprep-xx.txt, (a work in
progress).
Internationalized Strings ('stringprep')", draft-hoffman-
rfc3454bis-xx.txt, a work in progress.
-
-
-
-Sermersheim Internet-Draft - Expires Feb 2005 Page 41
-\f
- Lightweight Directory Access Protocol Version 3
-
[Syntaxes] Legg, S., and K. Dally, "LDAP: Syntaxes and Matching
Rules", draft-ietf-ldapbis-syntaxes-xx.txt, (a work in
progress).
<http://www.unicode.org/unicode/reports/tr17/>, August
2000.
+
+
+
+
+Sermersheim Internet-Draft - Expires Apr 2005 Page 41
+ Lightweight Directory Access Protocol Version 3
+
[PROTOS-LDAP] University of Oulu, "PROTOS Test-Suite: c06-ldapv3"
<http://www.ee.oulu.fi/research/ouspg/protos/testing/c06/l
dapv3/>
10. IANA Considerations
-
-Sermersheim Internet-Draft - Expires Feb 2005 Page 42
-\f
- Lightweight Directory Access Protocol Version 3
-
It is requested that the Internet Assigned Numbers Authority (IANA)
update the LDAP result code registry to indicate that this document
provides the definitive technical specification for result codes 0-
-
-
-
-
-
-
-
-
-
-Sermersheim Internet-Draft - Expires Feb 2005 Page 43
-\f
+Sermersheim Internet-Draft - Expires Apr 2005 Page 42
Lightweight Directory Access Protocol Version 3
Appendix A - LDAP Result Codes
version.
+
-Sermersheim Internet-Draft - Expires Feb 2005 Page 44
-\f
+Sermersheim Internet-Draft - Expires Apr 2005 Page 43
Lightweight Directory Access Protocol Version 3
For extended operations only, this code indicates that the
saslBindInProgress (14)
+
-Sermersheim Internet-Draft - Expires Feb 2005 Page 45
-\f
+Sermersheim Internet-Draft - Expires Apr 2005 Page 44
Lightweight Directory Access Protocol Version 3
Indicates the server requires the client to send a new bind
where it was not allowed or where access was denied.
-Sermersheim Internet-Draft - Expires Feb 2005 Page 46
-\f
+Sermersheim Internet-Draft - Expires Apr 2005 Page 45
Lightweight Directory Access Protocol Version 3
inappropriateAuthentication (48)
For example, this code is returned when a client attempts to
modify the structural object class of an entry.
-Sermersheim Internet-Draft - Expires Feb 2005 Page 47
-\f
+Sermersheim Internet-Draft - Expires Apr 2005 Page 46
Lightweight Directory Access Protocol Version 3
+
-Sermersheim Internet-Draft - Expires Feb 2005 Page 48
-\f
+Sermersheim Internet-Draft - Expires Apr 2005 Page 47
Lightweight Directory Access Protocol Version 3
Appendix B - Complete ASN.1 Definition
RelativeLDAPDN ::= LDAPString -- Constrained to <name-component>
-Sermersheim Internet-Draft - Expires Feb 2005 Page 49
-\f
+Sermersheim Internet-Draft - Expires Apr 2005 Page 48
Lightweight Directory Access Protocol Version 3
-- [LDAPDN]
aliasDereferencingProblem (36),
-- 37-47 unused --
-Sermersheim Internet-Draft - Expires Feb 2005 Page 50
-\f
+Sermersheim Internet-Draft - Expires Apr 2005 Page 49
Lightweight Directory Access Protocol Version 3
inappropriateAuthentication (48),
serverSaslCreds [7] OCTET STRING OPTIONAL }
-Sermersheim Internet-Draft - Expires Feb 2005 Page 51
-\f
+Sermersheim Internet-Draft - Expires Apr 2005 Page 50
Lightweight Directory Access Protocol Version 3
UnbindRequest ::= [APPLICATION 2] NULL
-- <attributeSelection> in Section 4.5.1
Filter ::= CHOICE {
- and [0] SET SIZE (1..MAX) OF filter Filter,
- or [1] SET SIZE (1..MAX) OF filter Filter,
+ and [0] SET OF filter Filter,
+ or [1] SET OF filter Filter,
not [2] Filter,
equalityMatch [3] AttributeValueAssertion,
substrings [4] SubstringFilter,
attributes PartialAttributeList }
-Sermersheim Internet-Draft - Expires Feb 2005 Page 52
-\f
+Sermersheim Internet-Draft - Expires Apr 2005 Page 51
Lightweight Directory Access Protocol Version 3
PartialAttributeList ::= SEQUENCE OF
COMPONENTS OF LDAPResult,
responseName [10] LDAPOID OPTIONAL,
-Sermersheim Internet-Draft - Expires Feb 2005 Page 53
-\f
+Sermersheim Internet-Draft - Expires Apr 2005 Page 52
Lightweight Directory Access Protocol Version 3
responseValue [11] OCTET STRING OPTIONAL }
+
-Sermersheim Internet-Draft - Expires Feb 2005 Page 54
-\f
+Sermersheim Internet-Draft - Expires Apr 2005 Page 53
Lightweight Directory Access Protocol Version 3
Appendix C - Changes
- Clarified that the messageID of requests MUST be non-zero.
+
-Sermersheim Internet-Draft - Expires Feb 2005 Page 55
-\f
+Sermersheim Internet-Draft - Expires Apr 2005 Page 54
Lightweight Directory Access Protocol Version 3
- Clarified when it is and isn't appropriate to return an already
- Stated that LDAPOID is constrained to <numericoid> from [Models].
-C.1.7 Section 4.1.5.1
+C.1.7 Section 4.1.5.1 and others
- Removed the Binary Option from the specification. There are
numerous interoperability problems associated with this method of
replacement is ongoing.
-C.1.8 Section 4.1.6
-
- - Removed references to the "binary" encoding as it has been removed
- from the specification.
-
-
-C.1.9 Section 4.1.7
-
- - Removed references to the "binary" encoding as it has been removed
- from the specification.
-
-
-C.1.10 Section 4.1.8
+C.1.8 Section 4.1.8
- Combined the definitions of PartialAttribute and Attribute here,
and defined Attribute in terms of PartialAttribute.
-C.1.11 Section 4.1.10
+C.1.9 Section 4.1.10
- Renamed "errorMessage" to "diagnosticMessage" as it is allowed to
be sent for non-error results.
listed in RFC 2251.
-C.1.12 Section 4.1.11
+C.1.10 Section 4.1.11
- Defined referrals in terms of URIs rather than URLs.
- Removed the requirement that all referral URIs MUST be equally
- Added the requirement that clients MUST NOT loop between servers.
- Clarified the instructions for using LDAPURLs in referrals, and in
doing so added a recommendation that the scope part be present.
-
-Sermersheim Internet-Draft - Expires Feb 2005 Page 56
-\f
- Lightweight Directory Access Protocol Version 3
-
-C.1.13 Section 4.1.12
+C.1.11 Section 4.1.12
- Specified how control values defined in terms of ASN.1 are to be
encoded.
on response messages and unbindRequest.
- Added language regarding combinations of controls and the ordering
of controls on a message.
+
+
+
+Sermersheim Internet-Draft - Expires Apr 2005 Page 55
+ Lightweight Directory Access Protocol Version 3
+
- Specified that when the semantics of the combination of controls
is undefined or unknown, it results in a protocolError.
- Changed "The server MUST be prepared" to "Implementations MUST be
controls).
-C.1.14 Section 4.2
+C.1.12 Section 4.2
- Mandated that servers return protocolError when the version is not
supported.
different clients.
-C.1.15 Section 4.2.1
+C.1.13 Section 4.2.1
- This section was largely reorganized for readability and language
was added to clarify the authentication state of failed and
- Dropped MUST imperative in paragraph 3 to align with [Keywords].
- Mandated that clients not send non-bind operations while a bind is
in progress, and suggested that servers not process them if they
-
-
-Sermersheim Internet-Draft - Expires Feb 2005 Page 57
-\f
- Lightweight Directory Access Protocol Version 3
-
are received. This is needed to ensure proper sequencing of the
bind in relationship to other operations.
-C.1.16 Section 4.2.3
+C.1.14 Section 4.2.3
- Moved most error-related text to Appendix A, and added text
regarding certain errors used in conjunction with the bind
- Prohibited the server from specifying serverSaslCreds when not
appropriate.
+
+Sermersheim Internet-Draft - Expires Apr 2005 Page 56
+ Lightweight Directory Access Protocol Version 3
+
-C.1.17 Section 4.3
+C.1.15 Section 4.3
- Required both peers to cease transmission and close the LDAP
exchange for the unbind operation.
-C.1.18 Section 4.4
+C.1.16 Section 4.4
- Added instructions for future specifications of Unsolicited
Notifications.
-C.1.19 Section 4.5.1
+C.1.17 Section 4.5.1
- SearchRequest attributes is now defined as an AttributeSelection
type rather than AttributeDescriptionList, and an ABNF is
instructed to ignore subsequent names when they are duplicated.
This was relaxed in order to allow different short names and also
OIDs to be requested for an attribute.
- - The Filter choices 'and' and 'or', and the SubstringFilter
- substrings types are now defined with a lower bound of 1.
+ - The Filter choice SubstringFilter substrings type is now defined
+ with a lower bound of 1.
- The SubstringFilter substrings 'initial, 'any', and 'final' types
are now AssertionValue rather than LDAPString. Also, added
imperatives stating that 'initial' (if present) must be listed
lessOrEqual, and approxMatch.
-C.1.20 Section 4.5.2
+C.1.18 Section 4.5.2
- Recommended that servers not use attribute short names when it
knows they are ambiguous or may cause interoperability problems.
implementation.
-
-Sermersheim Internet-Draft - Expires Feb 2005 Page 58
-\f
- Lightweight Directory Access Protocol Version 3
-
-C.1.21 Section 4.5.3
+C.1.19 Section 4.5.3
- Made changes similar to those made to Section 4.1.11.
-C.1.22 Section 4.5.3.1
+C.1.20 Section 4.5.3.1
- Fixed examples to adhere to changes made to Section 4.5.3.
-C.1.23 Section 4.6
+C.1.21 Section 4.6
+
+Sermersheim Internet-Draft - Expires Apr 2005 Page 57
+ Lightweight Directory Access Protocol Version 3
+
- Removed restriction that required an EQUALITY matching rule in
order to perform value delete modifications. It is sufficiently
documented that in absence of an equality matching rule, octet
violate schema.
-C.1.24 Section 4.7
+C.1.22 Section 4.7
- Aligned Add operation with X.511 in that the attributes of the RDN
are used in conjunction with the listed attributes to create the
present in the listed attributes.
-C.1.25 Section 4.9
+C.1.23 Section 4.9
- Required servers to not dereference aliases for modify DN. This
was added for consistency with other operations and to help ensure
present on the entry.
-C.1.26 Section 4.10
+C.1.24 Section 4.10
- Clarified that compareFalse means that the compare took place and
the result is false. There was confusion which lead people to
data consistency.
-C.1.27 Section 4.11
+C.1.25 Section 4.11
- Explained that since abandon returns no response, clients should
not use it if they need to know the outcome.
-
-Sermersheim Internet-Draft - Expires Feb 2005 Page 59
-\f
- Lightweight Directory Access Protocol Version 3
-
- Specified that Abandon and Unbind cannot be abandoned.
-C.1.28 Section 4.12
+C.1.26 Section 4.12
- Specified how values of extended operations defined in terms of
ASN.1 are to be encoded.
- Added a recommendation that servers advertise supported extended
operations.
+
+Sermersheim Internet-Draft - Expires Apr 2005 Page 58
+ Lightweight Directory Access Protocol Version 3
+
-C.1.29 Section 5.2
+C.1.27 Section 5.2
- Moved referral-specific instructions into referral-related
sections.
-C.1.30 Section 7
+C.1.28 Section 7
- Reworded notes regarding SASL not protecting certain aspects of
the LDAP bind PDU.
- Added a note regarding malformed and long encodings.
-C.1.31 Appendix A
+C.1.29 Appendix A
- - Added "EXTESIBILITY IMPLIED" to ASN.1 definition.
+ - Added "EXTENSIBILITY IMPLIED" to ASN.1 definition.
- Removed AttributeType. It is not used.
- Removed wording indicating that referrals can be returned from
StartTLS
-
-
-Sermersheim Internet-Draft - Expires Feb 2005 Page 60
-\f
- Lightweight Directory Access Protocol Version 3
-
- Removed requirement that only a narrow set of result codes can be
returned. Some result codes are required in certain scenarios, but
any other may be returned if appropriate.
C.3 Changes made to RFC 3771:
+
+Sermersheim Internet-Draft - Expires Apr 2005 Page 59
+ Lightweight Directory Access Protocol Version 3
+
- In general, all technical language was transferred in whole.
Supporting and background language seen as redundant due to its
+
+
+
+
+
+
+
+
+
+
+
+
+
+
-Sermersheim Internet-Draft - Expires Feb 2005 Page 61
-\f
+Sermersheim Internet-Draft - Expires Apr 2005 Page 60
Lightweight Directory Access Protocol Version 3
Intellectual Property Statement
-
+
The IETF takes no position regarding the validity or scope of any
Intellectual Property Rights or other rights that might be claimed to
pertain to the implementation or use of the technology described in
this document or the extent to which any license under such rights
might or might not be available; nor does it represent that it has
- made any independent effort to identify any such rights. Information
- on the IETF's procedures with respect to rights in IETF Documents can
- be found in BCP 78 and BCP 79.
-
+ made any independent effort to identify any such rights. Information
+ on the procedures with respect to rights in RFC documents can be
+ found in BCP 78 and BCP 79.
+
Copies of IPR disclosures made to the IETF Secretariat and any
assurances of licenses to be made available, or the result of an
attempt made to obtain a general license or permission for the use of
such proprietary rights by implementers or users of this
specification can be obtained from the IETF on-line IPR repository at
- http://www.ietf.org/ipr.
-
+ <http://www.ietf.org/ipr>.
+
The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary
rights that may cover technology that may be required to implement
- this standard. Please address the information to the IETF at ietf-
- ipr@ietf.org."
-
-
-Copyright Statement
-
- This document is subject to the rights, licenses and restrictions
- contained in BCP 78, and except as set forth therein, the authors
- retain all their rights.
-
+ this standard. Please address the information to the IETF at ietf-
+ ipr@ietf.org.
Disclaimer of Validity
-
+
This document and the information contained herein are provided on an
"AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
- WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
-
-
+ WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
+
+Copyright Statement
+
+ Copyright (C) The Internet Society (2004). This document is subject
+ to the rights, licenses and restrictions contained in BCP 78, and
+ except as set forth therein, the authors retain all their rights.
+
+Acknowledgement
+
+ Funding for the RFC Editor function is currently provided by the
+ Internet Society.
-Sermersheim Internet-Draft - Expires Feb 2005 Page 62
-
+Sermersheim Internet-Draft - Expires Apr 2005 Page 61
\ No newline at end of file
-
-
-
-
-
-
INTERNET-DRAFT Editor: Kurt D. Zeilenga
Intended Category: Standard Track OpenLDAP Foundation
-Expires in six months 15 February 2004
-Obsoletes: RFC 2251-2256, 2829-2830, 3377
+Expires in six months 24 October 2004
+Obsoletes: RFC 2251-2256, 2829-2830, 3377, 3771
+
Lightweight Directory Access Protocol (LDAP):
Technical Specification Road Map
- <draft-ietf-ldapbis-roadmap-04.txt>
+ <draft-ietf-ldapbis-roadmap-06.txt>
+
+
Status of this Memo
- This document is an Internet-Draft and is in full conformance with all
- provisions of Section 10 of RFC2026.
This document is intended to be published as a Standard Track RFC.
Distribution of this memo is unlimited. Technical discussion of this
mailing list <ietf-ldapbis@openldap.org>. Please send editorial
comments directly to the author <Kurt@OpenLDAP.org>.
+
+ By submitting this Internet-Draft, I accept the provisions of Section
+ 4 of RFC 3667. By submitting this Internet-Draft, I certify that any
+ applicable patent or other IPR claims of which I am aware have been
+ disclosed, or will be disclosed, and any of which I become aware will
+ be disclosed, in accordance with RFC 3668.
+
+
Internet-Drafts are working documents of the Internet Engineering Task
- Force (IETF), its areas, and its working groups. Note that other
+ Force (IETF), its areas, and its working groups. Note that other
groups may also distribute working documents as Internet-Drafts.
+
+
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
- time. It is inappropriate to use Internet-Drafts as reference
- material or to cite them other than as ``work in progress.''
+ time. It is inappropriate to use Internet-Drafts as reference material
+ or to cite them other than as "work in progress."
+
The list of current Internet-Drafts can be accessed at
- <http://www.ietf.org/ietf/1id-abstracts.txt>. The list of
+ <http://www.ietf.org/ietf/1id-abstracts.txt>. The list of
Internet-Draft Shadow Directories can be accessed at
<http://www.ietf.org/shadow.html>.
+
Copyright (C) The Internet Society (2004). All Rights Reserved.
+
Please see the Full Copyright section near the end of this document
for more information.
+
+
+
+
+
+Zeilenga LDAP: TS Road Map [Page 1]
+INTERNET-DRAFT draft-ietf-ldapbis-roadmap-06 24 October 2004
+
+
+
Abstract
+
The Lightweight Directory Access Protocol (LDAP) is an Internet
protocol for accessing distributed directory services which act in
accordance with X.500 data and service models. This document provides
-Zeilenga LDAP: TS Road Map [Page 1]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-roadmap-04 15 February 2004
-
-
Conventions
+
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in BCP 14 [RFC2119].
+
1. The LDAP Technical Specification
+
The technical specification detailing version 3 of the Lightweight
Directory Access Protocol (LDAP), an Internet Protocol, consists of
this document and the following documents:
+
LDAP: The Protocol [Protocol],
LDAP: Directory Information Models [Models],
LDAP: Authentication Methods and Connection Level Security
LDAP: Internationalized String Preparation [LDAPprep], and
LDAP: User Schema [Schema].
+
The terms "LDAP" and "LDAPv3" are commonly used to informally refer to
the protocol specified by this technical specification. The LDAP
suite, as defined here, should be formally identified in other
documents by a normative reference to this document.
- Extensions to LDAP may be specified in other documents. Nomenclature
- denoting such combinations of LDAP-plus-extension(s) is not defined by
- this document but may be defined in some future document(s).
+
+ LDAP is an extensible protocol. Extensions to LDAP may be specified
+ in other documents. Nomenclature denoting such combinations of
+ LDAP-plus-extension(s) is not defined by this document but may be
+ defined in some future document(s). Extensions are expected to be
+ truly optional.
+
IANA (Internet Assigned Numbers Authority) considerations for LDAP
described in BCP 64 [BCP64bis] apply fully to this revision of the
LDAP technical specification.
+
+
+
+
+Zeilenga LDAP: TS Road Map [Page 2]
+INTERNET-DRAFT draft-ietf-ldapbis-roadmap-06 24 October 2004
+
+
+
2. Relationship to X.500
+
This technical specification defines LDAP in terms of [X.500] as an
X.500 access mechanism. An LDAP server MUST act in accordance with
X.500(1993) series of International Telecommunication Union - Telecom
[X.501][X.511] as used in LDAP is not violated in the LDAP interface.
-
-Zeilenga LDAP: TS Road Map [Page 2]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-roadmap-04 15 February 2004
-
-
This technical specification explicitly incorporates portions of
X.500(93). Later revisions of X.500 do not automatically apply.
+
3. Security Considerations
+
LDAP security considerations are discussed in each document comprising
the technical specification.
+
4. Relationship to Obsolete Specifications
+
This technical specification, as defined in Section 1, obsoletes
entirely the previously defined LDAP technical specification [RFC3377]
- (which consists of RFC 2251-2256, RFC 2829-2830 and RFC 3377 itself).
- The technical specification was significantly reorganized.
+ (which consists of RFC 2251-2256, RFC 2829-2830, RFC 3771, and RFC
+ 3377 itself). The technical specification was significantly
+ reorganized.
+
This document replaces RFC 3377 as well as Section 3.3 of RFC 2251.
[Models] replaces portions of RFC 2251, RFC 2252 and RFC 2256.
- [Protocol] replaces the majority RFC 2251 and portions of RFC 2252.
- [AuthMeth] replaces RFC 2829, RFC 2830, and portions of RFC 2251.
- [Syntaxes] replaces the majority of RFC 2252 and portions of RFC 2256.
- [Schema] replaces the majority of RFC 2256. [LDAPDN] replaces RFC
- 2253. [Filters] replaces RFC 2254. [LDAPURL] replaces RFC 2255.
+ [Protocol] replaces the majority RFC 2251, portions of RFC 2252, and
+ all of RFC 3771. [AuthMeth] replaces RFC 2829, RFC 2830, and portions
+ of RFC 2251. [Syntaxes] replaces the majority of RFC 2252 and
+ portions of RFC 2256. [Schema] replaces the majority of RFC 2256.
+ [LDAPDN] replaces RFC 2253. [Filters] replaces RFC 2254. [LDAPURL]
+ replaces RFC 2255.
+
[LDAPprep] is new to this revision of the LDAP technical
specification.
+
Each document of this specification contains appendices summarizing
changes to all sections of the specifications they replace. Appendix
A.1 of this document details changes made to RFC 3377. Appendix A.2
of this document details changes made to Section 3.3 of RFC 2251.
+
Additionally, portions of this technical specification update and/or
- replace documents not listed above. These relationships are discussed
- in the documents detailings these portions of this technical
- specification.
+ replace a number of other documents not listed above. These
+
+
+
+
+Zeilenga LDAP: TS Road Map [Page 3]
+INTERNET-DRAFT draft-ietf-ldapbis-roadmap-06 24 October 2004
+
+
+
+ relationships are discussed in the documents detailings these portions
+ of this technical specification.
+
5. Acknowledgments
+
This document is based largely on RFC 3377 by J. Hodges and R.
Morgan, a product of the LDAPBIS and LDAPEXT Working Groups. The
document also borrows from RFC 2251 by M. Wahl, T. Howes, and S.
Kille, a product of the ASID Working Group.
- This document is a product of the IETF LDAPBIS Working Group.
-
-
+ This document is a product of the IETF LDAPBIS Working Group.
-Zeilenga LDAP: TS Road Map [Page 3]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-roadmap-04 15 February 2004
6. Author's Address
+
Kurt Zeilenga
E-mail: <kurt@openldap.org>
+
7. References
+
+ [[Note to the RFC Editor: please replace the citation tags used in
+ referencing Internet-Drafts with tags of the form RFCnnnn.]]
+
+
+
7.1. Normative References
+
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14 (also RFC 2119), March 1997.
- [BCP64bis] Zeilenga, K., "IANA Considerations for LDAP", draft-
- ietf-ldapbis-bcp64-xx.txt, a work in progress.
+
+ [BCP64bis] Zeilenga, K., "IANA Considerations for LDAP",
+ draft-ietf-ldapbis-bcp64-xx.txt, a work in progress.
+
[Protocol] Sermersheim, J. (editor), "LDAP: The Protocol",
draft-ietf-ldapbis-protocol-xx.txt, a work in progress.
+
[Models] Zeilenga, K. (editor), "LDAP: Directory Information
Models", draft-ietf-ldapbis-models-xx.txt, a work in
progress.
+
[AuthMeth] Harrison, R. (editor), "LDAP: Authentication Methods and
Connection Level Security Mechanisms",
draft-ietf-ldapbis-authmeth-xx.txt, a work in progress.
+
[LDAPDN] Zeilenga, K. (editor), "LDAP: String Representation of
Distinguished Names", draft-ietf-ldapbis-dn-xx.txt, a
work in progress.
+
+
+
+Zeilenga LDAP: TS Road Map [Page 4]
+INTERNET-DRAFT draft-ietf-ldapbis-roadmap-06 24 October 2004
+
+
+
[Filters] Smith, M. (editor), LDAPbis WG, "LDAP: String
Representation of Search Filters",
draft-ietf-ldapbis-filter-xx.txt, a work in progress.
+
[LDAPURL] Smith, M. (editor), "LDAP: Uniform Resource Locator",
draft-ietf-ldapbis-url-xx.txt, a work in progress.
+
[Syntaxes] Legg, S. (editor), "LDAP: Syntaxes and Matching Rules",
draft-ietf-ldapbis-syntaxes-xx.txt, a work in progress.
+
[LDAPprep] Zeilenga, K., "LDAP: Internationalized String
Preparation", draft-ietf-ldapbis-strprep-xx.txt, a work
in progress.
+
[Schema] Dally, K. (editor), "LDAP: User Schema",
draft-ietf-ldapbis-user-schema-xx.txt, a work in
progress.
-
-Zeilenga LDAP: TS Road Map [Page 4]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-roadmap-04 15 February 2004
-
-
[X.500] International Telecommunication Union -
Telecommunication Standardization Sector, "The Directory
-- Overview of concepts, models and services,"
X.500(1993) (also ISO/IEC 9594-1:1994).
+
[X.501] International Telecommunication Union -
Telecommunication Standardization Sector, "The Directory
-- Models," X.501(1993) (also ISO/IEC 9594-2:1994).
+
[X.511] International Telecommunication Union -
Telecommunication Standardization Sector, "The
- Directory: Abstract Service Definition", X.511(1993).
+ Directory: Abstract Service Definition", X.511(1993)
+ (also ISO/IEC 9594-3:1993).
+
7.2. Informative References
+
None.
+
Appendix A. Changes to Previous Documents
+
This appendix outlines changes this document makes relative to the
documents it replaces (in whole or in part).
+
Appendix A.1. Changes to RFC 3377
+
This document is nearly a complete rewrite of RFC 3377 as much of the
material of RFC 3377 is no longer applicable. The changes include
+
+
+
+
+Zeilenga LDAP: TS Road Map [Page 5]
+INTERNET-DRAFT draft-ietf-ldapbis-roadmap-06 24 October 2004
+
+
+
redefining the terms "LDAP" and "LDAPv3" to refer to this revision of
the technical specification.
+
Appendix A.2. Changes to Section 3.3 of RFC 2251
+
The section was modified slightly (the word "document" was replaced
with "technical specification") to clarify that it applies to the
entire LDAP technical specification.
-Intellectual Property Rights
- The IETF takes no position regarding the validity or scope of any
- intellectual property or other rights that might be claimed to pertain
- to the implementation or use of the technology described in this
- document or the extent to which any license under such rights might or
- might not be available; neither does it represent that it has made any
+Intellectual Property Rights
+ The IETF takes no position regarding the validity or scope of any
+ Intellectual Property Rights or other rights that might be claimed to
+ pertain to the implementation or use of the technology described in
+ this document or the extent to which any license under such rights
+ might or might not be available; nor does it represent that it has
+ made any independent effort to identify any such rights. Information
+ on the procedures with respect to rights in RFC documents can be found
+ in BCP 78 and BCP 79.
-Zeilenga LDAP: TS Road Map [Page 5]
-\f
-INTERNET-DRAFT draft-ietf-ldapbis-roadmap-04 15 February 2004
+ Copies of IPR disclosures made to the IETF Secretariat and any
+ assurances of licenses to be made available, or the result of an
+ attempt made to obtain a general license or permission for the use of
+ such proprietary rights by implementers or users of this specification
+ can be obtained from the IETF on-line IPR repository at
+ http://www.ietf.org/ipr.
- effort to identify any such rights. Information on the IETF's
- procedures with respect to rights in standards-track and
- standards-related documentation can be found in BCP-11. Copies of
- claims of rights made available for publication and any assurances of
- licenses to be made available, or the result of an attempt made to
- obtain a general license or permission for the use of such proprietary
- rights by implementors or users of this specification can be obtained
- from the IETF Secretariat.
The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary
- rights which may cover technology that may be required to practice
- this standard. Please address the information to the IETF Executive
- Director.
+ rights that may cover technology that may be required to implement
+ this standard. Please address the information to the IETF at
+ ietf-ipr@ietf.org.
+
Full Copyright
- Copyright (C) The Internet Society (2004). All Rights Reserved.
- This document and translations of it may be copied and furnished to
- others, and derivative works that comment on or otherwise explain it
- or assist in its implementation may be prepared, copied, published and
- distributed, in whole or in part, without restriction of any kind,
- provided that the above copyright notice and this paragraph are
- included on all such copies and derivative works. However, this
- document itself may not be modified in any way, such as by removing
- the copyright notice or references to the Internet Society or other
- Internet organizations, except as needed for the purpose of
- developing Internet standards in which case the procedures for
- copyrights defined in the Internet Standards process must be followed,
- or as required to translate it into languages other than English.
+ Copyright (C) The Internet Society (2004). This document is subject
+ to the rights, licenses and restrictions contained in BCP 78, and
+ except as set forth therein, the authors retain all their rights.
+ This document and the information contained herein are provided on an
+ "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
+ OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
+ ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
+Zeilenga LDAP: TS Road Map [Page 6]
+INTERNET-DRAFT draft-ietf-ldapbis-roadmap-06 24 October 2004
+ INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
+ INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
+ WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
-Zeilenga LDAP: TS Road Map [Page 6]
-\f
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+Zeilenga LDAP: TS Road Map [Page 7]
\ No newline at end of file
-
Network Working Group Mark Smith, Editor
Request for Comments: DRAFT Pearl Crescent, LLC
Obsoletes: RFC 2255 Tim Howes
-Expires: 13 August 2004 Opsware, Inc.
+Expires: 24 April 2005 Opsware, Inc.
- 13 February 2004
+ 24 October 2004
LDAP: Uniform Resource Locator
- <draft-ietf-ldapbis-url-05.txt>
+ <draft-ietf-ldapbis-url-07.txt>
+
+Status of this Memo
-1. Status of this Memo
+ By submitting this Internet-Draft, each author represents that any
+ applicable patent or other IPR claims of which he or she is aware
+ have been or will be disclosed, and any of which he or she become
+ aware will be disclosed, in accordance with RFC 3668.
- This document is an Internet-Draft and is subject to all provisions
- of Section 10 of RFC2026.
+ This document is intended to be published as a Standards Track RFC,
+ replacing RFC 2255. Distribution of this memo is unlimited.
+ Technical discussion of this document will take place on the IETF
+ LDAP (v3) Revision (ldapbis) Working Group mailing list
+ <ietf-ldapbis@openldap.org>. Please send editorial comments directly
+ to the editor <mcs@pearlcrescent.com>.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that
- other groups may also distribute working documents as Internet-
- Drafts.
+ other groups may also distribute working documents as
+ Internet-Drafts.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
- time. It is inappropriate to use Internet- Drafts as reference
- material or to cite them other than as "work in progress."
+ time. It is inappropriate to use Internet-Drafts as reference
+ material or to cite them other than a "work in progress."
The list of current Internet-Drafts can be accessed at
http://www.ietf.org/1id-abstracts.html
The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html
- Discussion of this document should take place on the LDAP (v3)
- Revision (ldapbis) Working Group mailing list <ietf-
- ldapbis@openldap.org>.
+ Copyright (C) The Internet Society (2004). All Rights Reserved.
+ Please see the Full Copyright section near the end of this document
+ for more information.
+
+
+
+
-Copyright (C) The Internet Society (2004). All Rights Reserved.
+Smith & Howes Intended Category: Standards Track [Page 1]
+\f
+INTERNET-DRAFT LDAP: Uniform Resource Locator 24 October 2004
-2. Abstract
+
+Abstract
This document describes a format for an LDAP Uniform Resource Locator
(URL). An LDAP URL describes an LDAP search operation that is used
an LDAPv3 referral or reference, an LDAP URL describes a service
where an LDAP operation may be progressed.
-
-
-
-Smith & Howes Intended Category: Standards Track [Page 1]
-\f
-INTERNET-DRAFT LDAP: Uniform Resource Locator 13 February 2004
-
-
-3. Table of Contents
-
-1. Status of this Memo............................................1
-2. Abstract.......................................................1
-3. Table of Contents..............................................2
-4. Introduction...................................................2
-5. URL Definition.................................................3
-5.1. Escaping Using the % Method.................................4
-6. Defaults for Fields of the LDAP URL............................5
-7. Examples.......................................................5
-8. Security Considerations........................................7
-9. Normative References...........................................8
-10. Informative References.........................................9
-11. Intellectual Property Rights...................................9
-12. Acknowledgements...............................................10
-13. Authors' Addresses.............................................10
-14. Full Copyright Statement.......................................11
-15. Appendix A: Changes Since RFC 2255.............................11
-15.1. Technical Changes...........................................11
-15.2. Editorial Changes...........................................12
-16. Appendix B: Changes Since Previous Document Revision...........13
-16.1. Technical Changes...........................................14
-16.2. Editorial Changes...........................................14
-
-4. Introduction
+Table of Contents
+
+ Status of this Memo............................................1
+ Abstract.......................................................2
+ Table of Contents..............................................2
+1. Introduction...................................................2
+2. URL Definition.................................................3
+2.1. Escaping Using the % Method.................................5
+3. Defaults for Fields of the LDAP URL............................5
+4. Examples.......................................................6
+5. Security Considerations........................................8
+6. IANA Considerations............................................9
+7. Normative References...........................................9
+8. Informative References.........................................10
+9. Intellectual Property Rights...................................10
+10. Acknowledgements...............................................10
+11. Authors' Addresses.............................................11
+12. Appendix A: Changes Since RFC 2255.............................11
+12.1. Technical Changes...........................................11
+12.2. Editorial Changes...........................................12
+13. Appendix B: Changes Since Previous Document Revision...........13
+13.1. Editorial Changes...........................................14
+14. Intellectual Property Rights...................................14
+15. Full Copyright.................................................14
+
+1. Introduction
LDAP is the Lightweight Directory Access Protocol, defined in
[Protocol]. This document specifies the LDAP URL format for version
This document is an integral part of the LDAP Technical Specification
[Roadmap].
- This document replaces RFC 2255. See Appendix A for a list of changes
- relative to RFC 2255.
-
- The key words "MUST", "MAY", and "SHOULD" used in this document are
- to be interpreted as described in [RFC2119].
-
-
-
-
Smith & Howes Intended Category: Standards Track [Page 2]
\f
-INTERNET-DRAFT LDAP: Uniform Resource Locator 13 February 2004
+INTERNET-DRAFT LDAP: Uniform Resource Locator 24 October 2004
+
+
+ This document replaces RFC 2255. See Appendix A for a list of changes
+ relative to RFC 2255.
+ The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
+ "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
+ document are to be interpreted as described in BCP 14 [RFC2119].
-5. URL Definition
+2. URL Definition
An LDAP URL begins with the protocol prefix "ldap" and is defined by
the following grammar, following the ABNF notation defined in
[QUESTION [filter] [QUESTION extensions]]]]]
scheme = "ldap"
hostport = <hostport from Section 3.2.2 of [RFC2396]>
- ; as updated by [RFC2732] to allow IPv6 literal addresses
+ ; As updated by [RFC2732] to allow
+ ; IPv6 literal addresses
dn = <distinguishedName from Section 3 of [LDAPDN]>
- ; see the "Escaping Using the % Method" section below.
+ ; See the "Escaping Using the % Method"
+ ; section below.
attributes = attrdesc *(COMMA attrdesc)
- attrdesc = <AttributeDescription from Section 4.1.4 of [Protocol]>
+ attrdesc = <AttributeDescription
+ from Section 4.1.4 of [Protocol]>
/ ASTERISK
- ; see the "Escaping Using the % Method" section below.
+ ; See the "Escaping Using the % Method"
+ ; section below.
scope = "base" / "one" / "sub"
filter = <filter from Section 4 of [Filters]>
- ; see the "Escaping Using the % Method" section below.
+ ; See the "Escaping Using the % Method"
+ ; section below.
extensions = extension *(COMMA extension)
extension = [EXCLAMATION] extype [EQUALS exvalue]
extype = oid / oiddescr
exvalue = <LDAPString from section 4.1.2 of [Protocol]>
- ; see the "Escaping Using the % Method" section below.
+ ; See the "Escaping Using the % Method"
+ ; section below.
oid = <LDAPOID from section 4.1.2 of [Protocol]>
oiddescr = <name from section 3.3 of [LDAPIANA]>
EXCLAMATION = %x21 ; exclamation mark ("!")
ASTERISK = %x2A ; asterisk ("*")
+ SLASH = %x2F ; forward slash ("/")
COLON = %x3A ; colon (":")
QUESTION = %x3F ; question mark ("?")
- SLASH = %x5C; forward slash ("/")
- The "ldap" prefix indicates an entry or entries residing in the LDAP
- server running on the given hostname at the given portnumber. Note
- that the hostport may contain literal IPv6 addresses as specified in
- [RFC2732].
+
+
+Smith & Howes Intended Category: Standards Track [Page 3]
+\f
+INTERNET-DRAFT LDAP: Uniform Resource Locator 24 October 2004
+
+
+ The "ldap" prefix indicates an entry or entries accessible from the
+ LDAP server running on the given hostname at the given portnumber.
+ Note that the hostport may contain literal IPv6 addresses as
+ specified in [RFC2732].
The dn is an LDAP Distinguished Name using the string format
described in [LDAPDN]. It identifies the base object of the LDAP
be returned from the entry or entries. Individual attrdesc names are
as defined for AttributeDescription in [Protocol].
-
-
-Smith & Howes Intended Category: Standards Track [Page 3]
-\f
-INTERNET-DRAFT LDAP: Uniform Resource Locator 13 February 2004
-
-
The scope construct is used to specify the scope of the search to
perform in the given LDAP server. The allowable scopes are "base"
for a base object search, "one" for a one-level search, or "sub" for
LDAP URL extensions are not necessarily related to any of the LDAPv3
extension mechanisms. Extensions may be supported or unsupported by
the client resolving the URL. An extension prefixed with a '!'
- character (ASCII 33) is critical. An extension not prefixed with a
+ character (ASCII 0x21) is critical. An extension not prefixed with a
'!' character is non-critical.
- If an LDAP URL extension is recognized by an implementation, the
+ If an LDAP URL extension is implemented (that is, if the
+ implementation understands it and is able to use it), the
implementation MUST make use of it. If an extension is not
- recognized and is marked critical, the implementation MUST NOT
- process the URL. If an extension is not recognized and it not marked
- critical, the implementation MUST ignore the extension.
+ implemented and is marked critical, the implementation MUST NOT
+ process the URL. If an extension is not implemented and it not
+ marked critical, the implementation MUST ignore the extension.
The extension type (extype) MAY be specified using the oid form
(e.g., 1.2.3.4) or the oiddesc form (e.g., myLDAPURLExtension). Use
No LDAP URL extensions are defined in this document. Other documents
or a future version of this document MAY define one or more
+
+
+
+Smith & Howes Intended Category: Standards Track [Page 4]
+\f
+INTERNET-DRAFT LDAP: Uniform Resource Locator 24 October 2004
+
+
extensions.
-5.1. Escaping Using the % Method
+2.1. Escaping Using the % Method
A generated LDAP URL MUST consist only of the restricted set of
characters included in the uric production that is defined in section
[RFC2396] or in the unreserved set defined in section 2.3 of
[RFC2396].
-
-
-Smith & Howes Intended Category: Standards Track [Page 4]
-\f
-INTERNET-DRAFT LDAP: Uniform Resource Locator 13 February 2004
-
-
It is the single Reserved character '?' and occurs inside a dn,
filter, or other element of an LDAP URL.
It is a comma character ',' that occurs inside an extension value.
-6. Defaults for Fields of the LDAP URL
+ Note that before the % method of escaping is applied, the extensions
+ component of the LDAP URL may contain one or more null (zero) bytes.
+ No other component may.
+
+3. Defaults for Fields of the LDAP URL
Some fields of the LDAP URL are optional, as described above. In the
absence of any other specification, the following general defaults
request to a NULL list, or (in LDAPv3) by requesting the special
attribute name "*").
+
+
+Smith & Howes Intended Category: Standards Track [Page 5]
+\f
+INTERNET-DRAFT LDAP: Uniform Resource Locator 24 October 2004
+
+
scope
If scope is omitted, a scope of "base" is assumed.
If extensions is omitted, no extensions are assumed.
-7. Examples
+4. Examples
The following are some example LDAP URLs using the format defined
above. The first example is an LDAP URL referring to the University
of Michigan entry, available from an LDAP server of the client's
choosing:
-
-
-
-
-Smith & Howes Intended Category: Standards Track [Page 5]
-\f
-INTERNET-DRAFT LDAP: Uniform Resource Locator 13 February 2004
-
-
ldap:///o=University%20of%20Michigan,c=US
The next example is an LDAP URL referring to the University of
The next example is an LDAP URL referring to all children of the c=GB
entry:
+
+
+Smith & Howes Intended Category: Standards Track [Page 6]
+\f
+INTERNET-DRAFT LDAP: Uniform Resource Locator 24 October 2004
+
+
ldap://ldap1.example.com/c=GB?objectClass?one
The objectClass attribute is requested to be returned along with the
illustrates the interaction between the LDAP string representation of
filters quoting mechanism and URL quoting mechanisms.
-
-
-
-
-Smith & Howes Intended Category: Standards Track [Page 6]
-\f
-INTERNET-DRAFT LDAP: Uniform Resource Locator 13 February 2004
-
-
ldap://ldap3.example.com/o=Babsco,c=US
???(four-octet=%5c00%5c00%5c00%5c04)
These three URLs all point to the root DSE on the ldap.example.net
server.
+
+
+
+
+Smith & Howes Intended Category: Standards Track [Page 7]
+\f
+INTERNET-DRAFT LDAP: Uniform Resource Locator 24 October 2004
+
+
The final two examples show use of a hypothetical, experimental bind
name extension (the value associated with the extension is an LDAP DN).
ldap:///??sub??e-bindname=cn=Manager%2cdc=example%2cdc=com
ldap:///??sub??!e-bindname=cn=Manager%2cdc=example%2cdc=com
- The two URLs are the same, except that the second one marks the e-
- bindname extension as critical. Notice the use of the % encoding
+ The two URLs are the same, except that the second one marks the
+ e-bindname extension as critical. Notice the use of the % encoding
method to encode the commas within the distinguished name value in
the e-bindname extension.
-8. Security Considerations
+5. Security Considerations
General URL security considerations discussed in [RFC2396] are
relevant for LDAP URLs.
-
-
-Smith & Howes Intended Category: Standards Track [Page 7]
-\f
-INTERNET-DRAFT LDAP: Uniform Resource Locator 13 February 2004
-
-
The use of security mechanisms when processing LDAP URLs requires
particular care, since clients may encounter many different servers
via URLs, and since URLs are likely to be processed automatically,
methods that do not reveal sensitive information is much preferred.
If the URL represents a referral for an update operation, strong
authentication methods SHOULD be used. Please refer to the Security
+
+
+
+Smith & Howes Intended Category: Standards Track [Page 8]
+\f
+INTERNET-DRAFT LDAP: Uniform Resource Locator 24 October 2004
+
+
Considerations section of [AuthMeth] for more information.
The LDAP URL format allows the specification of an arbitrary LDAP
search, etc. The security implications of resolving an LDAP URL are
the same as those of resolving an LDAP search query.
-9. Normative References
+6. IANA Considerations
+
+ This document has no actions for IANA.
+
+7. Normative References
[AuthMeth] Harrison, R. (editor), "LDAP: Authentication Methods",
draft-ietf-ldapbis-authmeth-xx.txt, a work in progress. a
[LDAPDN] Zeilenga, K. (editor), "LDAP: String Representation of
Distinguished Names", draft-ietf-ldapbis-dn-xx.txt, a work
-
-
-
-Smith & Howes Intended Category: Standards Track [Page 8]
-\f
-INTERNET-DRAFT LDAP: Uniform Resource Locator 13 February 2004
-
-
in progress.
[Filters] Smith, M. and Howes, T., "LDAP: String Representation of
Search Filters", draft-ietf-ldapbis-filter-xx.txt, a work in
progress.
-[LDAPIANA] Zeilenga, K., "IANA Considerations for LDAP", draft-ietf-
- ldapbis-bcp64-xx.txt, a work in progress.
+[LDAPIANA] Zeilenga, K., "IANA Considerations for LDAP",
+ draft-ietf-ldapbis-bcp64-xx.txt, a work in progress.
[RFC2119] Bradner, S., "Key Words for use in RFCs to Indicate
Requirement Levels," RFC 2119, BCP 14, March 1997.
-[Protocol] Sermersheim, J. (editor), "LDAP: The Protocol", draft-ietf-
- ldapbis-protocol-xx.txt, a work in progress.
+[Protocol] Sermersheim, J. (editor), "LDAP: The Protocol",
+ draft-ietf-ldapbis-protocol-xx.txt, a work in progress.
[RFC2234] Crocker, D., Overell, P., "Augmented BNF for Syntax
Specifications: ABNF", RFC 2234, November 1997.
[Roadmap] K. Zeilenga (editor), "LDAP: Technical Specification Road
Map", draft-ietf-ldapbis-roadmap-xx.txt, a work in progress.
+
+
+Smith & Howes Intended Category: Standards Track [Page 9]
+\f
+INTERNET-DRAFT LDAP: Uniform Resource Locator 24 October 2004
+
+
[RFC3629] Yergeau, F., "UTF-8, a transformation format of ISO 10646",
RFC 3629, November 2003.
-10. Informative References
+8. Informative References
None.
-11. Intellectual Property Rights
+9. Intellectual Property Rights
The IETF takes no position regarding the validity or scope of any
intellectual property or other rights that might be claimed to
claims of rights made available for publication and any assurances of
licenses to be made available, or the result of an attempt made to
obtain a general license or permission for the use of such
-
-
-
-Smith & Howes Intended Category: Standards Track [Page 9]
-\f
-INTERNET-DRAFT LDAP: Uniform Resource Locator 13 February 2004
-
-
proprietary rights by implementors or users of this specification can
be obtained from the IETF Secretariat.
this standard. Please address the information to the IETF Executive
Director.
-12. Acknowledgements
+10. Acknowledgements
The LDAP URL format was originally defined at the University of
Michigan. This material is based upon work supported by the National
Kurt Zeilenga, Jim Sermersheim, and Hallvard Furuseth deserve special
thanks for their contributions.
-13. Authors' Addresses
+
+
+
+
+Smith & Howes Intended Category: Standards Track [Page 10]
+\f
+INTERNET-DRAFT LDAP: Uniform Resource Locator 24 October 2004
+
+
+11. Authors' Addresses
Mark Smith, Editor
Pearl Crescent, LLC
+1 408 744-7509
howes@opsware.com
+12. Appendix A: Changes Since RFC 2255
-
-
-
-
-
-Smith & Howes Intended Category: Standards Track [Page 10]
-\f
-INTERNET-DRAFT LDAP: Uniform Resource Locator 13 February 2004
-
-
-14. Full Copyright Statement
-
- Copyright (C) The Internet Society (2004). All Rights Reserved.
-
- This document and translations of it may be copied and furnished to
- others, and derivative works that comment on or otherwise explain it
- or assist in its implementation may be prepared, copied, published
- and distributed, in whole or in part, without restriction of any
- kind, provided that the above copyright notice and this paragraph are
- included on all such copies and derivative works. However, this
- document itself may not be modified in any way, such as by removing
- the copyright notice or references to the Internet Society or other
- Internet organizations, except as needed for the purpose of
- developing Internet standards in which case the procedures for
- copyrights defined in the Internet Standards process must be
- followed, or as required to translate it into languages other than
- English.
-
- The limited permissions granted above are perpetual and will not be
- revoked by the Internet Society or its successors or assigns.
-
- This document and the information contained herein is provided on an
- "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
- TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
- BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
- HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
- MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
-
-15. Appendix A: Changes Since RFC 2255
-
-15.1. Technical Changes
+12.1. Technical Changes
The following technical changes were made to the contents of the "URL
Definition" section:
Added angle brackets around free-form prose in the "dn", "hostport",
"attrdesc", "filter", and "exvalue" rules.
-
-
-
-
-Smith & Howes Intended Category: Standards Track [Page 11]
-\f
-INTERNET-DRAFT LDAP: Uniform Resource Locator 13 February 2004
-
-
Changed the ABNF for ldapurl to group the dn component with the
preceding slash.
Reordered rules to more closely follow the order the elements appear
in the URL.
+
+
+
+
+Smith & Howes Intended Category: Standards Track [Page 11]
+\f
+INTERNET-DRAFT LDAP: Uniform Resource Locator 24 October 2004
+
+
"Bindname Extension": removed due to lack of known implementations.
-15.2. Editorial Changes
+12.2. Editorial Changes
Changed document title to include "LDAP:" prefix.
"Abstract" section: separated from introductory material.
- "Table of Contents" section: added.
+ "Table of Contents" and "IANA Considerations" sections: added.
"Introduction" section: new section; separated from the Abstract.
Changed the text indicate that RFC 2255 is replaced by this document
"URL Definition" section: removed second copy of ldapurl grammar and
following two paragraphs (editorial error in RFC 2255). Fixed line
- break within '!' sequence. Reworded last paragraph to clarify which
+ break within '!' sequence. Replaced "residing in the LDAP server"
+ with "accessible from the LDAP server" in the sentence immediately
+ following the ABNF. Reworded last paragraph to clarify which
characters must be URL escaped. Added text to indicate that LDAP
URLs are used for references and referrals. Added text that refers
to the ABNF from RFC 2234. Clarified and strengthened the
requirements with respect to processing of URLs that contain
- recognized and unrecognized extensions (the approach now matches that
- specified in [Protocol] for LDAP controls).
+ implements and not implemented extensions (the approach now closely
+ matches that specified in [Protocol] for LDAP controls).
"Defaults for Fields of the LDAP URL" section: added; formed by
moving text about defaults out of the "URL Definition" section.
-
-
-Smith & Howes Intended Category: Standards Track [Page 12]
-\f
-INTERNET-DRAFT LDAP: Uniform Resource Locator 13 February 2004
-
-
"URL Processing" section: clarified that connections MAY be reused
only if the open connection is compatible with the URL. Added text
to indicate that use of security services is encouraged and that they
discussion of authentication methods. Added note that the client MAY
interrogate the server to determine the most appropriate method.
+
+
+
+Smith & Howes Intended Category: Standards Track [Page 12]
+\f
+INTERNET-DRAFT LDAP: Uniform Resource Locator 24 October 2004
+
+
"Examples" section: Modified examples to use example.com and
example.net hostnames. Added missing '?' to the LDAP URL example
whose filter contains three null bytes. Removed space after one
Copyright: updated the year.
-16. Appendix B: Changes Since Previous Document Revision
+13. Appendix B: Changes Since Previous Document Revision
This appendix lists all changes relative to the previously published
- revision, draft-ietf-ldapbis-url-04.txt. Note that when appropriate
+ revision, draft-ietf-ldapbis-url-06.txt. Note that when appropriate
these changes are also included in Appendix A, but are also included
+ here for the benefit of the people who have already reviewed
+ draft-ietf-ldapbis-url-06.txt. This section will be removed before
+ this document is published as an RFC.
+
+
+
+
Smith & Howes Intended Category: Standards Track [Page 13]
\f
-INTERNET-DRAFT LDAP: Uniform Resource Locator 13 February 2004
+INTERNET-DRAFT LDAP: Uniform Resource Locator 24 October 2004
- here for the benefit of the people who have already reviewed draft-
- ietf-ldapbis-url-04.txt. This section will be removed before this
- document is published as an RFC.
+13.1. Editorial Changes
+ "Status of this Memo" section: replaced RFC 3668 (IPR) boilerplate
+ paragraph with the version that says "each author" instead of "I."
-16.1. Technical Changes
+ "URL Definition" section: replaced phrases such as "recognized by"
+ with "implemented by" when referring to LDAP URL extensions.
- Clarified and strengthened the requirements with respect to
- processing of URLs that contain recognized and unrecognized
- extensions (the approach now matches that specified in [Protocol] for
- LDAP controls).
+ "URL Definition" section: added the following two sentences at the
+ end of the subsection on "Escaping Using the % Method":
+ Note that before the % method of escaping is applied, the
+ extensions component of the LDAP URL may contain one or more null
+ (zero) bytes. No other component may.
+14. Intellectual Property Rights
-16.2. Editorial Changes
+ The IETF takes no position regarding the validity or scope of any
+ Intellectual Property Rights or other rights that might be claimed to
+ pertain to the implementation or use of the technology described in
+ this document or the extent to which any license under such rights
+ might or might not be available; nor does it represent that it has
+ made any independent effort to identify any such rights. Information
+ on the procedures with respect to rights in RFC documents can be
+ found in BCP 78 and BCP 79.
+
+ Copies of IPR disclosures made to the IETF Secretariat and any
+ assurances of licenses to be made available, or the result of an
+ attempt made to obtain a general license or permission for the use of
+ such proprietary rights by implementers or users of this
+ specification can be obtained from the IETF on-line IPR repository at
+ http://www.ietf.org/ipr.
- "URL Definition" section: corrected a section reference to
- [Protocol].
+ The IETF invites any interested party to bring to its attention any
+ copyrights, patents or patent applications, or other proprietary
+ rights that may cover technology that may be required to implement
+ this standard. Please address the information to the IETF at
+ ietf-ipr@ietf.org.
- "Examples" section: improved formatting and fixed a typographic error
- (removed extraneous "IP") in the "four-octet" example.
+15. Full Copyright
- "Normative References" section: changed the UTF-8 reference to point
- to RFC 3629, changed the RFC 3383 reference to point to the LDAP IANA
- Internet Draft, and indented the reference descriptions to enhance
- readability.
+ Copyright (C) The Internet Society (2004). This document is subject
+ to the rights, licenses and restrictions contained in BCP 78, and
+ except as set forth therein, the authors retain all their rights.
- Authors' Addresses section: New contact information for Mark Smith.
+ This document and the information contained herein are provided on an
+ "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
+ OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
+ ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
- Updated the copyright year to 2004.
-This Internet Draft expires on 13 August 2004.
+Smith & Howes Intended Category: Standards Track [Page 14]
+\f
+INTERNET-DRAFT LDAP: Uniform Resource Locator 24 October 2004
+ INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
+ INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
+ WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
+This Internet Draft expires on 24 April 2005.
-Smith & Howes Intended Category: Standards Track [Page 14]
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+Smith & Howes Intended Category: Standards Track [Page 15]
\f
--- /dev/null
+INTERNET-DRAFT Kurt D. Zeilenga
+Intended Category: Experimental OpenLDAP Foundation
+Expires in six months 17 October 2004
+
+
+ LDAP Modify-Increment Extension
+ <draft-zeilenga-ldap-incr-00.txt>
+
+
+Status of this Memo
+
+ This document is intended to be, after appropriate review and
+ revision, submitted to the RFC Editor as an Experimental document.
+ Distribution of this memo is unlimited. Technical discussion of this
+ document will take place on the IETF LDAP Extensions mailing list
+ <ldapext@ietf.org>. Please send editorial comments directly to the
+ author <Kurt@OpenLDAP.org>.
+
+ By submitting this Internet-Draft, I accept the provisions of Section
+ 4 of RFC 3667. By submitting this Internet-Draft, I certify that any
+ applicable patent or other IPR claims of which I am aware have been
+ disclosed, or will be disclosed, and any of which I become aware will
+ be disclosed, in accordance with RFC 3668.
+
+ Internet-Drafts are working documents of the Internet Engineering Task
+ Force (IETF), its areas, and its working groups. Note that other
+ groups may also distribute working documents as Internet-Drafts.
+
+ Internet-Drafts are draft documents valid for a maximum of six months
+ and may be updated, replaced, or obsoleted by other documents at any
+ time. It is inappropriate to use Internet-Drafts as reference material
+ or to cite them other than as "work in progress."
+
+ The list of current Internet-Drafts can be accessed at
+ <http://www.ietf.org/ietf/1id-abstracts.txt>. The list of
+ Internet-Draft Shadow Directories can be accessed at
+ <http://www.ietf.org/shadow.html>.
+
+ Copyright (C) The Internet Society (2004). All Rights Reserved.
+
+ Please see the Full Copyright section near the end of this document
+ for more information.
+
+
+Abstract
+
+ This document describes an extension to the Lightweight Directory
+ Access Protocol (LDAP) Modify operation to support an increment
+
+
+
+Zeilenga LDAP Modify-Increment Extension [Page 1]
+\f
+INTERNET-DRAFT draft-zeilenga-ldap-incr-00.txt 17 October 2004
+
+
+ capability. This extension is useful in provisioning applications,
+ especially when combined with the assertion control and/or the
+ pre-read or post-read control extension.
+
+
+1. Background and Intended Use
+
+ The Lightwieght Directory Access Protocol [Roadmap] does not currently
+ provide an operation to increment values of an attribute. A client
+ must read the values of the attribute, then modify those values to
+ increment them by the desired amount. As the values may be updated by
+ other clients between this add and modify, the client must be careful
+ to construct the modify request so that it fails in this case, and
+ upon failure, re-read the values and construct a new modify request.
+
+ This document extends the LDAP Modify Operation [Protocol] to support
+ an increment values capability. This feature is intended to be used
+ with either the LDAP pre-read or post-read control extension
+ [READENTRY]. This feature may be used with the LDAP assertion control
+ [ASSERT] to provide test-and-increment functionality.
+
+ The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
+ "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
+ document are to be interpreted as described in BCP 14 [RFC2119].
+
+
+2. The Modify-Increment Extension
+
+ This document extends the LDAP Modify request to support a increment
+ values capability. Implementations of this extension SHALL support an
+ additional ModifyRequest operation enumeration value increment (3) as
+ described herein. Implementations not supporting this extension will
+ treat this value as they would an unlisted value, e.g., as a protocol
+ error.
+
+ The increment (3) operation value specifies that an increment values
+ modification is requested. All existing values of the modification
+ attribute are to be incremented by the listed value. The modification
+ attribute must be appropriate for request, e.g., must have INTEGER or
+ other incrementable values, and the modification must provide one and
+ only value.
+
+ Servers supporting this feature SHOULD publish the object identifier
+ (OID) OID-TBD as a value of the 'supportedFeatures' [RFC3674]
+ attribute in the root DSE. Clients supporting this feature SHOULD NOT
+ use the feature unless they have knowledge the server supports it.
+
+
+
+
+
+Zeilenga LDAP Modify-Increment Extension [Page 2]
+\f
+INTERNET-DRAFT draft-zeilenga-ldap-incr-00.txt 17 October 2004
+
+
+ 3. LDIF Support
+
+ To represent Modify-Increment requests in LDAP Data Interchange Format
+ [RFC2849], the ABNF [RFC2234] production <mod-spec> is extended as
+ follows:
+
+ mod-spec /= "increment:" FILL AttributeDescription SEP
+ attrval-spec "-" SEP
+
+ For example,
+
+ # Increment uidNumber
+ dn: cn=max-assigned uidNumber,dc=example,dc=com
+ changetype: modify
+ increment: uidNumber
+ uidNumber: 1
+ -
+
+ This LDIF fragment represents a Modify request to increment the
+ value(s) of uidNumber by 1.
+
+
+4. Security Considerations
+
+ General LDAP security considerations [Roadmap], as well as those
+ specific to the LDAP Modify [Protocol], apply to this Modify-Increment
+ extension. Beyond these considerations, it is noted that introduction
+ of this extension should reduce application complexity (by provide one
+ operation what presently requires multiple operation) and, hence, may
+ aide in the production of correct and secure implementations.
+
+
+5. IANA Considerations
+
+ Registration of the LDAP Protocol Mechanism [BCP64bis] defined in
+ document is requested.
+
+ Subject: Request for LDAP Protocol Mechanism Registration
+ Object Identifier: OID-TBD
+ Description: Modify-Increment
+ Person & email address to contact for further information:
+ Kurt Zeilenga <kurt@openldap.org>
+ Usage: Feature
+ Specification: RFC XXXX
+ Author/Change Controller: Kurt Zeilenga <kurt@openldap.org>
+ Comments: none
+
+
+
+
+
+Zeilenga LDAP Modify-Increment Extension [Page 3]
+\f
+INTERNET-DRAFT draft-zeilenga-ldap-incr-00.txt 17 October 2004
+
+
+6. Author's Address
+
+ Kurt D. Zeilenga
+ OpenLDAP Foundation
+ <Kurt@OpenLDAP.org>
+
+
+7. Normative References
+
+ [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
+ Requirement Levels", BCP 14 (also RFC 2119), March 1997.
+
+ [RFC2234] Crocker, D. and P. Overell, "Augmented BNF for Syntax
+ Specifications: ABNF", RFC 2234, November 1997.
+
+ [RFC2849] Good, G., "The LDAP Data Interchange Format (LDIF) -
+ Technical Specification", RFC 2849, June 2000.
+
+ [Features] Zeilenga, K., "Feature Discovery in LDAP", RFC 3674,
+ December 2003.
+
+ [Roadmap] Zeilenga, K. (editor), "LDAP: Technical Specification
+ Road Map", draft-ietf-ldapbis-roadmap-xx.txt, a work in
+ progress.
+
+ [Protocol] Sermersheim, J. (editor), "LDAP: The Protocol",
+ draft-ietf-ldapbis-protocol-xx.txt, a work in progress.
+
+
+8. Informative References
+
+ [BCP64bis] Zeilenga, K., "IANA Considerations for LDAP",
+ draft-ietf-ldapbis-bcp64-xx.txt, a work in progress.
+
+ [READENTRY] Zeilenga, K., "LDAP Read Entry Controls",
+ draft-zeilenga-ldap-readentry-xx.txt, a work in
+ progress.
+
+ [ASSERT] Zeilenga, K., "LDAP Assertion Control",
+ draft-zeilenga-ldap-assert-xx.txt, a work in progress.
+
+ [ASSIGN] OpenLDAP Foundation, "OpenLDAP OID Delegations",
+ http://www.openldap.org/foundation/oid-delegate.txt.
+
+ [PRIVATE] IANA, "Private Enterprise Numbers",
+ http://www.iana.org/assignments/enterprise-numbers.
+
+
+
+
+
+Zeilenga LDAP Modify-Increment Extension [Page 4]
+\f
+INTERNET-DRAFT draft-zeilenga-ldap-incr-00.txt 17 October 2004
+
+
+Intellectual Property Rights
+
+ The IETF takes no position regarding the validity or scope of any
+ Intellectual Property Rights or other rights that might be claimed to
+ pertain to the implementation or use of the technology described in
+ this document or the extent to which any license under such rights
+ might or might not be available; nor does it represent that it has
+ made any independent effort to identify any such rights. Information
+ on the procedures with respect to rights in RFC documents can be found
+ in BCP 78 and BCP 79.
+
+ Copies of IPR disclosures made to the IETF Secretariat and any
+ assurances of licenses to be made available, or the result of an
+ attempt made to obtain a general license or permission for the use of
+ such proprietary rights by implementers or users of this specification
+ can be obtained from the IETF on-line IPR repository at
+ http://www.ietf.org/ipr.
+
+ The IETF invites any interested party to bring to its attention any
+ copyrights, patents or patent applications, or other proprietary
+ rights that may cover technology that may be required to implement
+ this standard. Please address the information to the IETF at
+ ietf-ipr@ietf.org.
+
+
+
+Full Copyright
+
+ Copyright (C) The Internet Society (2004). This document is subject
+ to the rights, licenses and restrictions contained in BCP 78, and
+ except as set forth therein, the authors retain all their rights.
+
+ This document and the information contained herein are provided on an
+ "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
+ OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
+ ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
+ INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
+ INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
+ WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
+
+
+
+
+
+
+
+
+
+
+
+
+Zeilenga LDAP Modify-Increment Extension [Page 5]
+\f
+
--- /dev/null
+
+INTERNET-DRAFT Kurt D. Zeilenga
+Intended Category: Standard Track OpenLDAP Foundation
+Expires in six months 17 October 2004
+Obsoletes: RFC 2252, RFC 2256
+
+
+ LDAP X.509 Certificate Schema
+ <draft-zeilenga-ldap-x509-00.txt>
+
+
+Status of this Memo
+
+ This document is intended to be, after appropriate review and
+ revision, submitted to the RFC Editor as an Standard Track document.
+ Distribution of this memo is unlimited. Technical discussion of this
+ document will take place on the IETF LDAP Extensions mailing list
+ <ldapext@ietf.org>. Please send editorial comments directly to the
+ author <Kurt@OpenLDAP.org>.
+
+ This document is intended to be published in conjunction to the
+ revised LDAP TS [Roadmap] when, in conjunction with this document,
+ obsoletes RFC 2252 and RFC 2256 in their entirety.
+
+ By submitting this Internet-Draft, I accept the provisions of Section
+ 4 of RFC 3667. By submitting this Internet-Draft, I certify that any
+ applicable patent or other IPR claims of which I am aware have been
+ disclosed, or will be disclosed, and any of which I become aware will
+ be disclosed, in accordance with RFC 3668.
+
+ Internet-Drafts are working documents of the Internet Engineering Task
+ Force (IETF), its areas, and its working groups. Note that other
+ groups may also distribute working documents as Internet-Drafts.
+
+ Internet-Drafts are draft documents valid for a maximum of six months
+ and may be updated, replaced, or obsoleted by other documents at any
+ time. It is inappropriate to use Internet-Drafts as reference material
+ or to cite them other than as "work in progress."
+
+ The list of current Internet-Drafts can be accessed at
+ <http://www.ietf.org/ietf/1id-abstracts.txt>. The list of
+ Internet-Draft Shadow Directories can be accessed at
+ <http://www.ietf.org/shadow.html>.
+
+ Copyright (C) The Internet Society (2004). All Rights Reserved.
+
+ Please see the Full Copyright section near the end of this document
+ for more information.
+
+
+
+
+Zeilenga draft-zeilenga-ldap-x509-00 [Page 1]
+\f
+INTERNET-DRAFT LDAP X.509 Schema 17 October 2004
+
+
+Abstract
+
+ This document describes schema for representing X.509 certificates,
+ X.521 security information, and related elements in directories
+ accessible using the Lightweight Directory Access Protocol (LDAP).
+ The LDAP definitions for these X.509 and X.521 schema elements
+ replaces those provided in RFC 2252 and RFC 2256.
+
+
+1. Background and Intended Use
+
+ This document provides LDAP schema definitions for a subset of
+ elements specified in X.509 [X.509] and X.521 [X.521], including
+ attribute types for certificates, cross certificate pairs, and
+ certificate revocation lists; matching rules to be used with these
+ attribute types; and related object classes. LDAP syntax definitions
+ are also provided for associated assertion and attribute values.
+
+ As the semantics of these elements are as defined in X.509 and X.521,
+ knowledge of X.509 and X.521 is necessary to make use of the LDAP
+ schema definitions provided herein.
+
+ This document, together with [Roadmap], obsoletes RFC 2252 and RFC
+ 2256 in their entirety. The changes made since RFC 2252 and RFC 2256
+ include:
+ - addition of pkiUser, pkiCA, and deltaCRL classes;
+ - updated of attribute types to include equality matching rules in
+ accordance with their X.500 specifications;
+ - addition of certificate, certificate pair, certificate list, and
+ algorithm identifer matching rules; and
+ - addition of LDAP syntax for assertion syntaxes for these matching
+ rules.
+
+ The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
+ "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
+ document are to be interpreted as described in BCP 14 [RFC2119].
+
+ Schema definitions are provided using LDAP description formats
+ [Models]. Definitions provided here are formatted (line wrapped) for
+ readability.
+
+
+2. Syntaxes
+
+ This section describes various syntaxes used to transfer certificates
+ and related data types in LDAP.
+
+
+
+
+
+Zeilenga draft-zeilenga-ldap-x509-00 [Page 2]
+\f
+INTERNET-DRAFT LDAP X.509 Schema 17 October 2004
+
+
+2.1. Certificate
+
+ ( 1.3.6.1.4.1.1466.115.121.1.8 DESC 'X.509 Certificate' )
+
+ A value of this syntax is an X.509 Certificate [Section 7, X.509].
+
+ Due to changes made to the ASN.1 definition of a Certificate made
+ through time, no LDAP-specific encoding is defined for this syntax.
+ Values of this syntax are to encoded using DER [X.690] and MUST only
+ be transferred using the ;binary transfer option [Binary]. That is,
+ by requesting and returning values using attribute descriptions such
+ as "userCertificate;binary".
+
+ As values of this syntax contain digitally-signed data, values of this
+ syntax, and the form of the value, MUST be preserved as presented.
+
+
+2.2. CertificateList
+
+ ( 1.3.6.1.4.1.1466.115.121.1.9 DESC 'X.509 Certificate List' )
+
+ A value of this syntax is an X.509 CertificateList [Section 7.3,
+ X.509].
+
+ Due to changes made to the ASN.1 definition of a CertificateList made
+ through time, no LDAP-specific encoding is defined for this syntax.
+ Values of this syntax are to encoded using DER [X.690] and MUST only
+ be transferred using the ;binary transfer option [Binary]. That is,
+ by requesting and returning values using attribute descriptions such
+ as "certificateRevocationList;binary".
+
+ As values of this syntax contain digitally-signed data, values of this
+ syntax, and the form of the value, MUST be preserved as presented.
+
+
+2.3. CertificatePair
+
+ ( 1.3.6.1.4.1.1466.115.121.1.10 DESC 'X.509 Certificate Pair' )
+
+ A value of this syntax is an X.509 CertificatePair [Section 11.2.3,
+ X.509].
+
+ Due to changes made to the ASN.1 definition of an X.509
+ CertificatePair made through time, no LDAP-specific encoding is
+ defined for this syntax. Values of this syntax are to encoded using
+ DER [X.690] and MUST only be transferred using the ;binary transfer
+ option [Binary]. That is, by requesting and returning values using
+ attribute descriptions such as "crossCertificatePair;binary".
+
+
+
+Zeilenga draft-zeilenga-ldap-x509-00 [Page 3]
+\f
+INTERNET-DRAFT LDAP X.509 Schema 17 October 2004
+
+
+ As values of this syntax contain digitally-signed data, values of this
+ syntax, and the form of the value, MUST be preserved as presented.
+
+2.4 SupportedAlgorithm
+
+ ( 1.3.6.1.4.1.1466.115.121.1.49
+ DESC 'X.508 Supported Algorithm' )
+
+ A value of this syntax is an X.509 SupportedAlgorithm [Section 11.2.7,
+ X.509].
+
+ Due to changes made to the ASN.1 definition of an X.509
+ SupportedAlgorithm made through time, no LDAP-specific encoding is
+ defined for this syntax. Values of this syntax are to encoded using
+ DER [X.690] and MUST only be transferred using the ;binary transfer
+ option [Binary]. That is, by requesting and returning values using
+ attribute descriptions such as "supportedAlgorithms;binary".
+
+ As values of this syntax contain digitally-signed data, values of this
+ syntax, and the form of the value, MUST be preserved as presented.
+
+
+2.5. CertificateExactAssertion
+
+ ( IANA-ASSIGNED-OID.1 DESC 'X.509 Certificate Exact Assertion' )
+
+ A value of this syntax is an X.509 CertificateExactAssertion [Section
+ 11.3.1, X.509].
+
+ The LDAP-specific encoding used for this syntax is described by the
+ following ABNF [RFC2234]:
+
+ certificateExactAssertion = serialNumber DOLLAR issuer
+ serialNumber = number
+ issuer = distinguishedName
+
+ where <number> and <DOLLAR> are as given in [Models] and
+ <distinguishedName> is as given in [LDAPDN].
+
+ Example: 10$cn=Example$CA,dc=example,dc=com
+
+ Note: DOLLAR ('$') characters may appear in the <issuer> production.
+
+
+2.6. CertificateAssertion
+
+ ( IANA-ASSIGNED-OID.2 DESC 'X.509 Certificate Assertion' )
+
+
+
+
+Zeilenga draft-zeilenga-ldap-x509-00 [Page 4]
+\f
+INTERNET-DRAFT LDAP X.509 Schema 17 October 2004
+
+
+ A value of this syntax is an X.509 CertificateAssertion [Section
+ 11.3.2, X.509].
+
+ Values of this syntax are to be encoded using GSER [RFC3641].
+ Appendix A.1 provides an equivalent ABNF grammar for this syntax.
+
+
+2.7. CertificatePairExactAssertion
+
+ ( IANA-ASSIGNED-OID.3
+ DESC 'X.509 Certificate Pair Exact Assertion' )
+
+ A value of this syntax is an X.509 CertificatePairExactAssertion
+ [Section 11.3.3, X.509].
+
+ Values of this syntax are to be encoded using GSER [RFC3641].
+ Appendix A.2 provides an equivalent ABNF grammar for this syntax.
+
+
+2.8. CertificatePairAssertion
+
+ ( IANA-ASSIGNED-OID.4 DESC 'X.509 Certificate Pair Assertion' )
+
+ A value of this syntax is an X.509 CertificatePairAssertion [Section
+ 11.3.4, X.509].
+
+ Values of this syntax are to be encoded using GSER [RFC3641].
+ Appendix A.3 provides an equivalent ABNF grammar for this syntax.
+
+
+2.9. CertificateListExactAssertion
+
+ ( IANA-ASSIGNED-OID.5
+ DESC 'X.509 Certificate List Exact Assertion' )
+
+ A value of this syntax is an X.509 CertificateListExactAssertion
+ [Section 11.3.5, X.509].
+
+ Values of this syntax are to be encoded using GSER [RFC3641].
+ Appendix A.4 provides an equivalent ABNF grammar for this syntax.
+
+
+2.10. CertificateListAssertion
+
+ ( IANA-ASSIGNED-OID.6 DESC 'X.509 Certificate List Assertion' )
+
+ A value of this syntax is an X.509 CertificateListAssertion [Section
+ 11.3.6, X.509].
+
+
+
+Zeilenga draft-zeilenga-ldap-x509-00 [Page 5]
+\f
+INTERNET-DRAFT LDAP X.509 Schema 17 October 2004
+
+
+ Values of this syntax are to be encoded using GSER [RFC3641].
+ Appendix A.5 provides an equivalent ABNF grammar for this syntax.
+
+
+2.11 AlgorithmIdentifier
+
+ ( IANA-ASSIGNED-OID.7 DESC 'X.509 Algorithm Identifier' )
+
+ A value of this syntax is an X.509 AlgorithmIdentifier [Section 7,
+ X.509].
+
+ Values of this syntax are to be encoded using GSER [RFC3641].
+ Appendix A.6 provides an equivalent ABNF grammar for this syntax.
+
+
+3. Matching Rules
+
+ This section introduces a set of certificate and related matching
+ rules for use in LDAP. These rules are intended to act in accordance
+ with their X.500 counterparts.
+
+
+3.1. certificateExactMatch
+
+ The certificateExactMatch matching rule compares the presented
+ certificate exact assertion value with an attribute value of the
+ certificate syntax as described in Section 11.3.1 of [X.509].
+
+ ( 2.5.13.34 NAME 'certificateExactMatch'
+ DESC 'X.509 Certificate Exact Match'
+ SYNTAX IANA-ASSIGNED-OID.1 )
+
+
+3.2. certificateMatch
+
+ The certificateMatch matching rule compares the presented certificate
+ assertion value with an attribute value of the certificate syntax as
+ described in Section 11.3.2 of [X.509].
+
+ ( 2.5.13.35 NAME 'certificateMatch'
+ DESC 'X.509 Certificate Match'
+ SYNTAX IANA-ASSIGNED-OID.2 )
+
+
+3.3. certificatePairExactMatch
+
+ The certificatePairExactMatch matching rule compares the presented
+ certificate pair exact assertion value with an attribute value of the
+
+
+
+Zeilenga draft-zeilenga-ldap-x509-00 [Page 6]
+\f
+INTERNET-DRAFT LDAP X.509 Schema 17 October 2004
+
+
+ certificate pair syntax as described in Section 11.3.3 of [X.509].
+
+ ( 2.5.13.36 NAME 'certificatePairExactMatch'
+ DESC 'X.509 Certificate Pair Exact Match'
+ SYNTAX IANA-ASSIGNED-OID.3 )
+
+
+3.4. certificatePairMatch
+
+ The certificatePairMatch matching rule compares the presented
+ certificate pair assertion value with an attribute value of the
+ certificate pair syntax as described in Section 11.3.4 of [X.509].
+
+ ( 2.5.13.37 NAME 'certificatePairMatch'
+ DESC 'X.509 Certificate Pair Match'
+ SYNTAX IANA-ASSIGNED-OID.4 )
+
+
+3.5. certificateListExactMatch
+
+ The certificateListExactMatch matching rule compares the presented
+ certificate list exact assertion value with an attribute value of the
+ certificate pair syntax as described in Section 11.3.5 of [X.509].
+
+ ( 2.5.13.38 NAME 'certificateListExactMatch'
+ DESC 'X.509 Certificate List Exact Match'
+ SYNTAX IANA-ASSIGNED-OID.5 )
+
+
+3.6. certificateListMatch
+
+ The certificateListMatch matching rule compares the presented
+ certificate list assertion value with an attribute value of the
+ certificate pair syntax as described in Section 11.3.6 of [X.509].
+
+ ( 2.5.13.39 NAME 'certificateListMatch'
+ DESC 'X.509 Certificate List Match'
+ SYNTAX IANA-ASSIGNED-OID.6 )
+
+
+3.7. algorithmIdentifierMatch
+
+ The algorithmIdentifierMatch mating rule compares a presented
+ algorithm identifier with an attribute value of supported algorithm as
+ described in Section 11.3.7 of [X.509].
+
+ ( 2.5.13.40 NAME 'algorithmIdentifier'
+ DESC 'X.509 Algorithm Identifier Match'
+
+
+
+Zeilenga draft-zeilenga-ldap-x509-00 [Page 7]
+\f
+INTERNET-DRAFT LDAP X.509 Schema 17 October 2004
+
+
+ SYNTAX IANA-ASSIGNED-OID.7 )
+
+
+4. Attribute Types
+
+ This section details a set of certificate and related attribute types
+ for use in LDAP.
+
+
+4.1. userCertificate
+
+ The userCertificate attribute holds the X.509 certificates issued to
+ the user by one or more certificate authorities, as discussed in
+ Section 11.2.1 of [X.509].
+
+ ( 2.5.4.36 NAME 'userCertificate'
+ DESC 'X.509 user certificate'
+ EQUALITY certificateExactMatch
+ SYNTAX 1.3.6.1.4.1.1466.115.121.1.8 )
+
+ As required by this attribute type's syntax, values of this attribute
+ are requested and transferred using the attribute description
+ "userCertificate;binary".
+
+
+4.2. cACertificate
+
+ The cACertificate attribute holds the X.509 certificates issued to the
+ certificate authority (CA), as discussed in Section 11.2.2 of [X.509].
+
+ ( 2.5.4.37 NAME 'cACertificate'
+ DESC 'X.509 CA certificate'
+ EQUALITY certificateExactMatch
+ SYNTAX 1.3.6.1.4.1.1466.115.121.1.8 )
+
+ As required by this attribute type's syntax, values of this attribute
+ are requested and transferred using the attribute description
+ "cACertificate;binary".
+
+
+4.3. crossCertificatePair
+
+ The crossCertificatePair attribute holds an X.509 certificate pair, as
+ discussed in Section 11.2.3 of [X.509].
+
+ ( 2.5.4.40 NAME 'crossCertificatePair'
+ DESC 'X.509 cross certificate pair'
+ EQUALITY certificatePairExactMatch
+
+
+
+Zeilenga draft-zeilenga-ldap-x509-00 [Page 8]
+\f
+INTERNET-DRAFT LDAP X.509 Schema 17 October 2004
+
+
+ SYNTAX 1.3.6.1.4.1.1466.115.121.1.10 )
+
+ As required by this attribute type's syntax, values of this attribute
+ are requested and transferred using the attribute description
+ "crossCertificatePair;binary".
+
+
+4.4. certificateRevocationList
+
+ The certificateRevocationList attribute holds certificate lists, as
+ discussed in 11.2.4 of [X.509].
+
+ ( 2.5.4.39 NAME 'certificateRevocationList'
+ DESC 'X.509 certificate revocation list'
+ EQUALITY certificateListExactMatch
+ SYNTAX 1.3.6.1.4.1.1466.115.121.1.9 )
+
+ As required by this attribute type's syntax, values of this attribute
+ are requested and transferred using the attribute description
+ "certificateRevocationList;binary".
+
+
+4.5. authorityRevocationList
+
+ The authorityRevocationList attribute holds certificate lists, as
+ discussed in 11.2.5 of [X.509].
+
+ ( 2.5.4.38 NAME 'authorityRevocationList'
+ DESC 'X.509 authority revocation list'
+ EQUALITY certificateListExactMatch
+ SYNTAX 1.3.6.1.4.1.1466.115.121.1.9 )
+
+ As required by this attribute type's syntax, values of this attribute
+ are requested and transferred using the attribute description
+ "authorityRevocationList;binary".
+
+
+4.6. deltaRevocationList
+
+ The deltaRevocationList attribute holds certificate lists, as
+ discussed in 11.2.6 of [X.509].
+
+ ( 2.5.4.53 NAME 'deltaRevocationList'
+ DESC 'X.509 delta revocation list'
+ EQUALITY certificateListExactMatch
+ SYNTAX 1.3.6.1.4.1.1466.115.121.1.9 )
+
+ As required by this attribute type's syntax, values of this attribute
+
+
+
+Zeilenga draft-zeilenga-ldap-x509-00 [Page 9]
+\f
+INTERNET-DRAFT LDAP X.509 Schema 17 October 2004
+
+
+ MUST be requested and transferred using the attribute description
+ "deltaRevocationList;binary".
+
+
+4.7. supportedAlgorithms
+
+ The supportedAlgorithms attribute holds supported algorithms, as
+ discussed in 11.2.7 of [X.509].
+
+ ( 2.5.4.52 NAME 'supportedAlgorithms'
+ DESC 'X.509 supported algorithms'
+ EQUALITY algorithmIdentifierMatch
+ SYNTAX 1.3.6.1.4.1.1466.115.121.1.49 )
+
+ As required by this attribute type's syntax, values of this attribute
+ MUST be requested and transferred using the attribute description
+ "supportedAlgorithms;binary".
+
+
+5. Object Classes
+
+ This section details a set of certificate-related object classes for
+ use in LDAP.
+
+
+5.1. pkiUser
+
+ This object class is used in augment entries for objects that may be
+ subject to certificates, as defined in Section 11.1.1 of [X.509].
+
+ ( 2.5.6.21 NAME 'pkiUser'
+ DESC 'X.509 PKI User'
+ SUP top AUXILIARY
+ MAY userCertificate )
+
+
+5.2. pkiCA
+
+ This object class is used to augment entries for objects which act as
+ certificate authorities, as defined in Section 11.1.2 of [X.509]
+
+ ( 2.5.6.22 NAME 'pkiCA'
+ DESC 'X.509 PKI Certificate Authority'
+ SUP top AUXILIARY
+ MAY ( cACertificate $ certificateRevocationList $
+ authorityRevocationList $ crossCertificatePair ) )
+
+
+
+
+
+Zeilenga draft-zeilenga-ldap-x509-00 [Page 10]
+\f
+INTERNET-DRAFT LDAP X.509 Schema 17 October 2004
+
+
+5.3. cRLDistributionPoint
+
+ This class is used to represent objects which act as CRL distribution
+ points, as discussed in Section 11.1.3 of [X.509].
+
+ ( 2.5.6.19 NAME 'cRLDistributionPoint'
+ DESC 'X.509 CRL distribution point'
+ SUP top STRUCTURAL
+ MUST cn
+ MAY ( certificateRevocationList $
+ authorityRevocationList $ deltaRevocationList ) )
+
+
+5.4 deltaCRL
+
+ The deltaCRL object class is used to augment entries no hold delta
+ revocation lists, as discussed in Section 11.1.4 of [X.509].
+
+ ( 2.5.6.23 NAME 'deltaCRL'
+ DESC 'X.509 delta CRL'
+ SUP top AUXILIARY
+ MAY deltaRevocationList )
+
+
+5.5. strongAuthenticationUser
+
+ This object class is used to augment entries for objects participating
+ in certificate-based authentication, as defined in Section 6.15 of
+ [X.521]. This object class is deprecated in favor of pkiUser.
+
+ ( 2.5.6.15 NAME 'strongAuthenticationUser'
+ DESC 'X.521 strong authentication user'
+ SUP top AUXILIARY
+ MUST userCertificate )
+
+
+5.6. userSecurityInformation
+
+ This object class is used to augment entries with needed additional
+ associated security information, as defined in Section 6.16 of
+ [X.521].
+
+ ( 2.5.6.18 NAME 'userSecurityInformation'
+ DESC 'X.521 user security information'
+ SUP top AUXILIARY
+ MAY ( supportedAlgorithms ) )
+
+
+
+
+
+Zeilenga draft-zeilenga-ldap-x509-00 [Page 11]
+\f
+INTERNET-DRAFT LDAP X.509 Schema 17 October 2004
+
+
+5.7. certificationAuthority
+
+ This object class is used to augment entries for objects which act as
+ certificate authorities, as defined in Section 6.17 of [X.521]. This
+ object class is deprecated in favor of pkiCA.
+
+ ( 2.5.6.16 NAME 'certificationAuthority'
+ DESC 'X.509 certificate authority'
+ SUP top AUXILIARY
+ MUST ( authorityRevocationList $
+ certificateRevocationList $ cACertificate )
+ MAY crossCertificatePair )
+
+
+5.8. certificationAuthority-V2
+
+ This object class is used to augment entries for objects which act as
+ certificate authorities, as defined in Section 6.18 of [X.521]. This
+ object class is deprecated in favor of pkiCA.
+
+ ( 2.5.6.16.2 NAME 'certificationAuthority-V2'
+ DESC 'X.509 certificate authority, version 2'
+ SUP certificationAuthority AUXILIARY
+ MAY deltaRevocationList )
+
+
+6. Security Considerations
+
+ The directory administrator is to use the server's access control
+ facilities to restrict access as desired.
+
+ General LDAP security considerations [Roadmap] apply.
+
+
+7. IANA Considerations
+
+7.1. Object Identifier Registration
+
+ It is requested that IANA register upon Standards Action an LDAP
+ Object Identifier for use in this technical specification.
+
+ Subject: Request for LDAP OID Registration
+ Person & email address to contact for further information:
+ Kurt Zeilenga <kurt@OpenLDAP.org>
+ Specification: RFC XXXX
+ Author/Change Controller: IESG
+ Comments:
+ Identifies the LDAP X.509 Certificate schema elements
+
+
+
+Zeilenga draft-zeilenga-ldap-x509-00 [Page 12]
+\f
+INTERNET-DRAFT LDAP X.509 Schema 17 October 2004
+
+
+7.2. Registration of the descriptor
+
+ It is requested that IANA update upon Standards Action the LDAP
+ Descriptor registry as indicated below.
+
+ Subject: Request for LDAP Descriptor Registration
+ Descriptor (short name): see table
+ Object Identifier: see table
+ Person & email address to contact for further information:
+ Kurt Zeilenga <kurt@OpenLDAP.org>
+ Usage: see table
+ Specification: RFC XXXX
+ Author/Change Controller: IESG
+
+ algorithmIdentifierMatch R 2.5.13.40
+ authorityRevocationList A 2.5.4.38 *
+ cACertificate A 2.5.4.37 *
+ cRLDistributionPoint O 2.5.6.19 *
+ certificateExactMatch R 2.5.13.34
+ certificateListExactMatch R 2.5.13.38
+ certificateListMatch R 2.5.13.39
+ certificateMatch R 2.5.13.35
+ certificatePairExactMatch R 2.5.13.36
+ certificatePairMatch R 2.5.13.37
+ certificateRevocationList A 2.5.4.39 *
+ certificationAuthority O 2.5.6.16 *
+ certificationAuthority-V2 O 2.5.6.16.2 *
+ crossCertificatePair A 2.5.4.40 *
+ deltaCRL O 2.5.6.23
+ deltaRevocationList A 2.5.4.53 *
+ pkiCA O 2.5.6.22
+ pkiUser O 2.5.6.21
+ strongAuthenticationUser O 2.5.6.15 *
+ supportedAlgorithms A 2.5.4.52 *
+ userCertificate A 2.5.4.36 *
+ userSecurityInformation O 2.5.6.18 *
+
+ * Updates previous registration
+
+
+8. Acknowledgments
+
+ This document is based upon X.509, a product of the ITU-T. A number
+ of LDAP schema definitions were based on those found RFC 2252 and RFC
+ 2256, both products of the IETF ASID WG.
+
+ Additional material was borrowed from prior works by David Chadwick
+ and/or Steven Legg to refine LDAP X.509 Schema.
+
+
+
+Zeilenga draft-zeilenga-ldap-x509-00 [Page 13]
+\f
+INTERNET-DRAFT LDAP X.509 Schema 17 October 2004
+
+
+9. Author's Address
+
+ Kurt D. Zeilenga
+ OpenLDAP Foundation
+
+ Email: Kurt@OpenLDAP.org
+
+
+10. Normative References
+
+ [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
+ Requirement Levels", BCP 14 (also RFC 2119), March 1997.
+
+ [RFC2234] Crocker, D. and P. Overell, "Augmented BNF for Syntax
+ Specifications: ABNF", RFC 2234, November 1997.
+
+ [RFC3641] Legg, S., "Generic String Encoding Rules for ASN.1
+ Types", RFC 3641, October 2003.
+
+ [Roadmap] Zeilenga, K. (editor), "LDAP: Technical Specification
+ Road Map", draft-ietf-ldapbis-roadmap-xx.txt, a work in
+ progress.
+
+ [Models] Zeilenga, K. (editor), "LDAP: Directory Information
+ Models", draft-ietf-ldapbis-models-xx.txt, a work in
+ progress.
+
+ [Binary] Legg, S., "Lightweight Directory Access Protocol (LDAP):
+ The Binary Encoding Option",
+ draft-legg-ldap-binary-xx.txt, a work in progress.
+
+ [X.509] International Telecommunication Union -
+ Telecommunication Standardization Sector, "The
+ Directory: Authentication Framework", X.509(2000).
+
+ [X.521] International Telecommunication Union -
+ Telecommunication Standardization Sector, "The
+ Directory: Selected Object Classes", X.521(2000).
+
+ [X.680] International Telecommunication Union -
+ Telecommunication Standardization Sector, "Abstract
+ Syntax Notation One (ASN.1) - Specification of Basic
+ Notation", X.680(1997) (also ISO/IEC 8824-1:1998).
+
+ [X.690] International Telecommunication Union -
+ Telecommunication Standardization Sector, "Specification
+ of ASN.1 encoding rules: Basic Encoding Rules (BER),
+ Canonical Encoding Rules (CER), and Distinguished
+
+
+
+Zeilenga draft-zeilenga-ldap-x509-00 [Page 14]
+\f
+INTERNET-DRAFT LDAP X.509 Schema 17 October 2004
+
+
+ Encoding Rules (DER)", X.690(1997) (also ISO/IEC
+ 8825-1:1998).
+
+
+11. Informative References
+
+ [RFC3383] Zeilenga, K., "IANA Considerations for LDAP", BCP 64
+ (also RFC 3383), September 2002.
+
+ [RFC3642] Legg, S., "Common Elements of GSER Encodings", RFC 3642,
+ October 2003.
+
+ [BCP64bis] Zeilenga, K., "IANA Considerations for LDAP",
+ draft-ietf-ldapbis-bcp64-xx.txt, a work in progress.
+
+
+Appendix A.
+
+ This appendix is informative.
+
+ This appendix, once written, will provide ABNF [RFC2234] grammars for
+ GSER-based LDAP-specific encodings specified in this document. These
+ grammars where produced using, and rely on, Common Elements for GSER
+ Encodings [RFC3342].
+
+
+
+Intellectual Property Rights
+
+ The IETF takes no position regarding the validity or scope of any
+ Intellectual Property Rights or other rights that might be claimed to
+ pertain to the implementation or use of the technology described in
+ this document or the extent to which any license under such rights
+ might or might not be available; nor does it represent that it has
+ made any independent effort to identify any such rights. Information
+ on the procedures with respect to rights in RFC documents can be found
+ in BCP 78 and BCP 79.
+
+ Copies of IPR disclosures made to the IETF Secretariat and any
+ assurances of licenses to be made available, or the result of an
+ attempt made to obtain a general license or permission for the use of
+ such proprietary rights by implementers or users of this specification
+ can be obtained from the IETF on-line IPR repository at
+ http://www.ietf.org/ipr.
+
+ The IETF invites any interested party to bring to its attention any
+ copyrights, patents or patent applications, or other proprietary
+ rights that may cover technology that may be required to implement
+
+
+
+Zeilenga draft-zeilenga-ldap-x509-00 [Page 15]
+\f
+INTERNET-DRAFT LDAP X.509 Schema 17 October 2004
+
+
+ this standard. Please address the information to the IETF at
+ ietf-ipr@ietf.org.
+
+
+
+Full Copyright
+
+ Copyright (C) The Internet Society (2004). This document is subject
+ to the rights, licenses and restrictions contained in BCP 78, and
+ except as set forth therein, the authors retain all their rights.
+
+ This document and the information contained herein are provided on an
+ "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
+ OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
+ ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
+ INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
+ INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
+ WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+Zeilenga draft-zeilenga-ldap-x509-00 [Page 16]
+\f
+
rfc3866.txt Language Tag and Ranges in LDAP (PS)
rfc3876.txt Returning Matched Values with LDAP (PS)
rfc3909.txt LDAP Cancel Operation (PS)
+rfc3928.txt LDAP Client Update Protocol (PS)
Legend:
STD Standard
--- /dev/null
+
+
+
+
+
+
+Network Working Group R. Megginson, Ed.
+Request for Comments: 3928 Netscape Communications Corp.
+Category: Standards Track M. Smith
+ Pearl Crescent, LLC
+ O. Natkovich
+ Yahoo
+ J. Parham
+ Microsoft Corporation
+ October 2004
+
+
+ Lightweight Directory Access Protocol (LDAP)
+ Client Update Protocol (LCUP)
+
+Status of this Memo
+
+ This document specifies an Internet standards track protocol for the
+ Internet community, and requests discussion and suggestions for
+ improvements. Please refer to the current edition of the "Internet
+ Official Protocol Standards" (STD 1) for the standardization state
+ and status of this protocol. Distribution of this memo is unlimited.
+
+Copyright Notice
+
+ Copyright (C) The Internet Society (2004).
+
+Abstract
+
+ This document defines the Lightweight Directory Access Protocol
+ (LDAP) Client Update Protocol (LCUP). The protocol is intended to
+ allow an LDAP client to synchronize with the content of a directory
+ information tree (DIT) stored by an LDAP server and to be notified
+ about the changes to that content.
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+Megginson, et al. Standards Track [Page 1]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+Table of Contents
+
+ 1. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
+ 2. Applicability. . . . . . . . . . . . . . . . . . . . . . . . . 4
+ 3. Specification of Protocol Elements . . . . . . . . . . . . . . 5
+ 3.1. ASN.1 Considerations . . . . . . . . . . . . . . . . . . 5
+ 3.2. Universally Unique Identifiers . . . . . . . . . . . . . 5
+ 3.3. LCUP Scheme and LCUP Cookie. . . . . . . . . . . . . . . 5
+ 3.4. LCUP Context . . . . . . . . . . . . . . . . . . . . . . 6
+ 3.5. Additional LDAP Result Codes defined by LCUP . . . . . . 6
+ 3.6. Sync Request Control . . . . . . . . . . . . . . . . . . 7
+ 3.7. Sync Update Control. . . . . . . . . . . . . . . . . . . 7
+ 3.8. Sync Done Control. . . . . . . . . . . . . . . . . . . . 8
+ 4. Protocol Usage and Flow. . . . . . . . . . . . . . . . . . . . 8
+ 4.1. LCUP Search Requests . . . . . . . . . . . . . . . . . . 8
+ 4.1.1. Initial Synchronization and Full Resync . . . . . 9
+ 4.1.2. Incremental or Update Synchronization . . . . . . 10
+ 4.1.3. Persistent Only . . . . . . . . . . . . . . . . . 10
+ 4.2. LCUP Search Responses. . . . . . . . . . . . . . . . . . 10
+ 4.2.1. Sync Update Informational Responses . . . . . . . 11
+ 4.2.2. Cookie Return Frequency . . . . . . . . . . . . . 11
+ 4.2.3. Definition of an Entry That Has Entered the
+ Result Set. . . . . . . . . . . . . . . . . . . . 12
+ 4.2.4. Definition of an Entry That Has Changed . . . . . 13
+ 4.2.5. Definition of an Entry That Has Left the
+ Result Set. . . . . . . . . . . . . . . . . . . . 13
+ 4.2.6. Results For Entries Present in the Result Set . . 14
+ 4.2.7. Results For Entries That Have Left the Result
+ Set . . . . . . . . . . . . . . . . . . . . . . . 14
+ 4.3. Responses Requiring Special Consideration . . . . . . . . 15
+ 4.3.1. Returning Results During the Persistent Phase . . 15
+ 4.3.2. No Mixing of Sync Phase with Persist Phase. . . . 16
+ 4.3.3. Returning Updated Results During the Sync Phase . 16
+ 4.3.4. Operational Attributes and Administrative
+ Entries . . . . . . . . . . . . . . . . . . . . . 16
+ 4.3.5. Virtual Attributes. . . . . . . . . . . . . . . . 17
+ 4.3.6. Modify DN and Delete Operations Applied to
+ Subtrees. . . . . . . . . . . . . . . . . . . . . 17
+ 4.3.7. Convergence Guarantees. . . . . . . . . . . . . . 18
+ 4.4. LCUP Search Termination. . . . . . . . . . . . . . . . . 18
+ 4.4.1. Server Initiated Termination. . . . . . . . . . . 18
+ 4.4.2. Client Initiated Termination. . . . . . . . . . . 19
+ 4.5. Size and Time Limits . . . . . . . . . . . . . . . . . . 19
+ 4.6. Operations on the Same Connection. . . . . . . . . . . . 19
+ 4.7. Interactions with Other Controls . . . . . . . . . . . . 19
+ 4.8. Replication Considerations . . . . . . . . . . . . . . . 20
+ 5. Client Side Considerations . . . . . . . . . . . . . . . . . . 20
+ 5.1. Using Cookies with Different Search Criteria . . . . . . 20
+
+
+
+Megginson, et al. Standards Track [Page 2]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+ 5.2. Renaming the Base Object . . . . . . . . . . . . . . . . 20
+ 5.3. Use of Persistent Searches With Respect to Resources . . 21
+ 5.4. Continuation References to Other LCUP Contexts . . . . . 21
+ 5.5. Referral Handling. . . . . . . . . . . . . . . . . . . . 21
+ 5.6. Multiple Copies of Same Entry During Sync Phase. . . . . 21
+ 5.7. Handling Server Out of Resources Condition . . . . . . . 21
+ 6. Server Implementation Considerations . . . . . . . . . . . . . 22
+ 6.1. Server Support for UUIDs . . . . . . . . . . . . . . . . 22
+ 6.2. Example of Using an RUV as the Cookie Value. . . . . . . 22
+ 6.3. Cookie Support Issues. . . . . . . . . . . . . . . . . . 22
+ 6.3.1. Support for Multiple Cookie Schemes . . . . . . . 22
+ 6.3.2. Information Contained in the Cookie . . . . . . . 23
+ 6.4. Persist Phase Response Time. . . . . . . . . . . . . . . 23
+ 6.5. Scaling Considerations . . . . . . . . . . . . . . . . . 23
+ 6.6. Alias Dereferencing. . . . . . . . . . . . . . . . . . . 24
+ 7. Synchronizing Heterogeneous Data Stores. . . . . . . . . . . . 24
+ 8. IANA Considerations. . . . . . . . . . . . . . . . . . . . . . 24
+ 9. Security Considerations. . . . . . . . . . . . . . . . . . . . 24
+ 10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 25
+ 10.1. Normative References . . . . . . . . . . . . . . . . . . 25
+ 10.2. Informative References . . . . . . . . . . . . . . . . . 26
+ 11. Acknowledgments. . . . . . . . . . . . . . . . . . . . . . . . 26
+ Appendix - Features Left Out of LCUP . . . . . . . . . . . . . . . 27
+ Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 29
+ Full Copyright Statement . . . . . . . . . . . . . . . . . . . . . 30
+
+1. Overview
+
+ The LCUP protocol is intended to allow LDAP clients to synchronize
+ with the content stored by LDAP servers.
+
+ The problem areas addressed by the protocol include:
+
+ - Mobile clients that maintain a local read-only copy of the
+ directory data. While off-line, the client uses the local copy of
+ the data. When the client connects to the network, it
+ synchronizes with the current directory content and can optionally
+ receive notification about the changes that occur while it is on-
+ line. For example, a mail client can maintain a local copy of the
+ corporate address book that it synchronizes with the master copy
+ whenever the client is connected to the corporate network.
+
+ - Applications intending to synchronize heterogeneous data stores.
+ A meta directory application, for instance, would periodically
+ retrieve a list of modified entries from the directory, construct
+ the changes and apply them to a foreign data store.
+
+
+
+
+
+Megginson, et al. Standards Track [Page 3]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+ - Clients that need to take certain actions when a directory entry
+ is modified. For instance, an electronic mail repository may want
+ to perform a "create mailbox" task when a new person entry is
+ added to an LDAP directory and a "delete mailbox" task when a
+ person entry is removed.
+
+ The problem areas not being considered:
+
+ - Directory server to directory server synchronization. The IETF is
+ developing a LDAP replication protocol, called LDUP [RFC3384],
+ which is specifically designed to address this problem area.
+
+ There are currently several protocols in use for LDAP client server
+ synchronization. While each protocol addresses the needs of a
+ particular group of clients (e.g., on-line clients or off-line
+ clients), none satisfies the requirements of all clients in the
+ target group. For instance, a mobile client that was off-line and
+ wants to become up to date with the server and stay up to date while
+ connected can't be easily supported by any of the existing protocols.
+
+ LCUP is designed such that the server does not need to maintain state
+ information specific to individual clients. The server may need to
+ maintain additional state information about attribute modifications,
+ deleted entries, and moved/renamed entries. The clients are
+ responsible for storing the information about how up to date they are
+ with respect to the server's content. LCUP design avoids the need
+ for LCUP-specific update agreements to be made between client and
+ server prior to LCUP use. The client decides when and from where to
+ retrieve the changes. LCUP design requires clients to initiate the
+ update session and "pull" the changes from server.
+
+ LCUP operations are subject to administrative and access control
+ policies enforced by the server.
+
+ The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
+ "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
+ document are to be interpreted as described in BCP 14, RFC 2119
+ [RFC2119].
+
+2. Applicability
+
+ LCUP will work best if the following conditions are met:
+
+ 1) The server stores some degree of historical state or change
+ information to reduce the amount of wire traffic required for
+ incremental synchronizations. The optimal balance between server
+ state and wire traffic varies amongst implementations and usage
+ scenarios, and is therefore left in the hands of implementers.
+
+
+
+Megginson, et al. Standards Track [Page 4]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+ 2) The client cannot be assumed to understand the physical
+ information model (virtual attributes, operational attributes,
+ subentries, etc.) implemented by the server. Optimizations would
+ be possible if such assumptions could be made.
+
+ 3) Meta data changes and renames and deletions of large subtrees are
+ very infrequent. LCUP makes these assumptions in order to reduce
+ client complexity required to deal with these special operations,
+ though when they do occur they may result in a large number of
+ incremental update messages or a full resync.
+
+3. Specification of Protocol Elements
+
+ The following sections define the new elements required to use this
+ protocol.
+
+3.1. ASN.1 Considerations
+
+ Protocol elements are described using ASN.1 [X.680]. The term "BER-
+ encoded" means the element is to be encoded using the Basic Encoding
+ Rules [X.690] under the restrictions detailed in Section 5.1 of
+ [RFC2251]. All ASN.1 in this document uses implicit tags.
+
+3.2. Universally Unique Identifiers
+
+ Distinguished names can change, so are therefore unreliable as
+ identifiers. A Universally Unique Identifier (or UUID for short)
+ MUST be used to uniquely identify entries used with LCUP. The UUID
+ is part of the Sync Update control value (see below) returned with
+ each search result. The server SHOULD provide the UUID as a single
+ valued operational attribute of the entry (e.g., "entryUUID"). We
+ RECOMMEND that the server provides a way to do efficient (i.e.,
+ indexed) searches for values of UUID, e.g., by using a search filter
+ like (entryUUID=<some UUID value>) to quickly search for and retrieve
+ an entry based on its UUID. Servers SHOULD use a UUID format as
+ specified in [UUID]. The UUID used by LCUP is a value of the
+ following ASN.1 type:
+
+ LCUPUUID ::= OCTET STRING
+
+3.3. LCUP Scheme and LCUP Cookie
+
+ The LCUP protocol uses a cookie to hold the state of the client's
+ data with respect to the server's data. Each cookie format is
+ uniquely identified by its scheme. The LCUP Scheme is a value of the
+ following ASN.1 type:
+
+ LCUPScheme ::= LDAPOID
+
+
+
+Megginson, et al. Standards Track [Page 5]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+ This is the OID which identifies the format of the LCUP Cookie value.
+ The scheme OID, as all object identifiers, MUST be unique for a given
+ cookie scheme. The cookie value may be opaque or it may be exposed
+ to LCUP clients. For cookie schemes that expose their value, the
+ preferred form of documentation is an RFC. It is expected that there
+ will be one or more standards track cookie schemes where the value
+ format is exposed and described in detail.
+
+ The LCUP Cookie is a value of the following ASN.1 type:
+
+ LCUPCookie ::= OCTET STRING
+
+ This is the actual data describing the state of the client's data.
+ This value may be opaque, or its value may have some well-known
+ format, depending on the scheme.
+
+ Further uses of the LCUP Cookie value are described below.
+
+3.4. LCUP Context
+
+ A part of the DIT which is enabled for LCUP is referred to as an LCUP
+ Context. A server may support one or more LCUP Contexts. For
+ example, a server with two naming contexts may support LCUP in one
+ naming context but not the other, or support different LCUP cookie
+ schemes in each naming context. Each LCUP Context MAY use a
+ different cookie scheme. An LCUP search will not cross an LCUP
+ Context boundary, but will instead return a SearchResultReference
+ message, with the LDAP URL specifying the same host and port as
+ currently being searched, and with the baseDN set to the baseDN of
+ the new LCUP Context. The client is then responsible for issuing
+ another search using the new baseDN, and possibly a different cookie
+ if that LCUP Context uses a different cookie. The client is
+ responsible for maintaining a mapping of the LDAP URL to its
+ corresponding cookie.
+
+3.5. Additional LDAP Result Codes defined by LCUP
+
+ Implementations of this specification SHALL recognize the following
+ additional resultCode values. The LDAP result code names and numbers
+ defined in the following table have been assigned by IANA per RFC
+ 3383 [RFC3383].
+
+ lcupResourcesExhausted (113) the server is running out of resources
+ lcupSecurityViolation (114) the client is suspected of malicious
+ actions
+ lcupInvalidData (115) invalid scheme or cookie was supplied
+ by the client
+
+
+
+
+Megginson, et al. Standards Track [Page 6]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+ lcupUnsupportedScheme (116) The cookie scheme is a valid OID but
+ is not supported by this server
+ lcupReloadRequired (117) indicates that client data needs to be
+ reinitialized. This reason is
+ returned if the server does not
+ contain sufficient information to
+ synchronize the client or if the
+ server's data was reloaded since the
+ last synchronization session
+
+ The uses of these codes are described below.
+
+3.6. Sync Request Control
+
+ The Sync Request Control is an LDAP Control [RFC2251, Section 4.1.2]
+ where the controlType is the object identifier 1.3.6.1.1.7.1 and the
+ controlValue, an OCTET STRING, contains a BER-encoded
+ syncRequestControlValue.
+
+ syncRequestControlValue ::= SEQUENCE {
+ updateType ENUMERATED {
+ syncOnly (0),
+ syncAndPersist (1),
+ persistOnly (2) },
+ sendCookieInterval [0] INTEGER OPTIONAL,
+ scheme [1] LCUPScheme OPTIONAL,
+ cookie [2] LCUPCookie OPTIONAL
+ }
+
+ sendCookieInterval - the server SHOULD send the cookie back in the
+ Sync Update control value (defined below) for every
+ sendCookieInterval number of SearchResultEntry and
+ SearchResultReference PDUs returned to the client. For example, if
+ the value is 5, the server SHOULD send the cookie back in the Sync
+ Update control value for every 5 search results returned to the
+ client. If this value is absent, zero or less than zero, the server
+ chooses the interval.
+
+ The Sync Request Control is only applicable to the searchRequest
+ message. Use of this control is described below.
+
+3.7. Sync Update Control
+
+ The Sync Update Control is an LDAP Control [RFC2251, Section 4.1.2]
+ where the controlType is the object identifier 1.3.6.1.1.7.2 and the
+ controlValue, an OCTET STRING, contains a BER-encoded
+ syncUpdateControlValue.
+
+
+
+
+Megginson, et al. Standards Track [Page 7]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+ syncUpdateControlValue ::= SEQUENCE {
+ stateUpdate BOOLEAN,
+ entryUUID [0] LCUPUUID OPTIONAL, -- REQUIRED for entries --
+ UUIDAttribute [1] AttributeType OPTIONAL,
+ entryLeftSet [2] BOOLEAN,
+ persistPhase [3] BOOLEAN,
+ scheme [4] LCUPScheme OPTIONAL,
+ cookie [5] LCUPCookie OPTIONAL
+ }
+
+ The field UUIDAttribute contains the name or OID of the attribute
+ that the client should use to perform searches for entries based on
+ the UUID. The client should be able to use it in an equality search
+ filter, e.g., "(<uuid attribute>=<entry UUID value>)" and should be
+ able to use it in the attribute list of the search request to return
+ its value. The UUIDAttribute field may be omitted if the server does
+ not support searching on the UUID values.
+
+ The Sync Update Control is only applicable to SearchResultEntry and
+ SearchResultReference messages. Although entryUUID is OPTIONAL, it
+ MUST be used with SearchResultEntry messages. Use of this control is
+ described below.
+
+3.8. Sync Done Control
+
+ The Sync Done Control is an LDAP Control [RFC2251, Section 4.1.2]
+ where the controlType is the object identifier 1.3.6.1.1.7.3 and the
+ controlValue contains a BER-encoded syncDoneValue.
+
+ syncDoneValue ::= SEQUENCE {
+ scheme [0] LCUPScheme OPTIONAL,
+ cookie [1] LCUPCookie OPTIONAL
+ }
+
+ The Sync Done Control is only applicable to SearchResultDone message.
+ Use of this control is described below.
+
+4. Protocol Usage and Flow
+
+4.1. LCUP Search Requests
+
+ A client initiates a synchronization or persistent search session
+ with a server by attaching a Sync Request control to an LDAP
+ searchRequest message. The search specification determines the part
+ of the directory information tree (DIT) the client wishes to
+ synchronize with, the set of attributes it is interested in and the
+ amount of data the client is willing to receive. The Sync Request
+ control contains the client's request specification.
+
+
+
+Megginson, et al. Standards Track [Page 8]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+ If there is an error condition, the server MUST immediately return a
+ SearchResultDone message with the resultCode set to an error code.
+ This table maps a condition to its corresponding behavior and
+ resultCode.
+
+ Condition Behavior or resultCode
+
+ Sync Request Control is not Server behaves as [RFC2251, Section
+ supported 4.1.2] - specifically, if the
+ criticality of the control is FALSE,
+ the server will process the request
+ as a normal search request
+
+ Scheme is not supported lcupUnsupportedScheme
+
+ A control value field is lcupInvalidData
+ invalid (e.g., illegal
+ updateType, or the scheme is
+ not a valid OID, or the cookie
+ is invalid)
+
+ Server is running out of lcupResourcesExhausted
+ resources
+
+ Server suspects client of lcupSecurityViolation
+ malicious behavior (frequent
+ connects/disconnects, etc.)
+
+ The server cannot bring the lcupReloadRequired
+ client up to date (server data
+ has been reloaded, or other
+ changes prevent
+ convergence)
+
+4.1.1. Initial Synchronization and Full Resync
+
+ For an initial synchronization or full resync, the fields of the Sync
+ Request control MUST be specified as follows:
+
+ updateType - MUST be set to syncOnly or syncAndPersist
+ sendCookieInterval - MAY be set
+ scheme - MAY be set - if set, the server MUST use this
+ specified scheme or return lcupUnsupportedScheme
+ (see above) - if not set, the server MAY use any
+ scheme it supports.
+ cookie - MUST NOT be set
+
+
+
+
+
+Megginson, et al. Standards Track [Page 9]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+ If the request was successful, the client will receive results as
+ described in the section "LCUP Search Responses" below.
+
+4.1.2. Incremental or Update Synchronization
+
+ For an incremental or update synchronization, the fields of the Sync
+ Request control MUST be specified as follows:
+
+ updateType - MUST be set to syncOnly or syncAndPersist
+ sendCookieInterval - MAY be set
+ scheme - MUST be set
+ cookie - MUST be set
+
+ The client SHOULD always use the latest cookie it received from the
+ server.
+
+ If the request was successful, the client will receive results as
+ described in the section "LCUP Search Responses" below.
+
+4.1.3. Persistent Only
+
+ For persistent only search request, the fields of the Sync Request
+ MUST be specified as follows:
+
+ updateType - MUST be set to persistOnly
+ sendCookieInterval - MAY be set
+ scheme - MAY be set - if set, the server MUST use this
+ specified scheme or return
+ lcupUnsupportedScheme (see above) - if not set,
+ the server MAY use any scheme it supports.
+ cookie - MAY be set, but the server MUST ignore it
+
+ If the request was successful, the client will receive results as
+ described in the section "LCUP Search Responses" below.
+
+4.2. LCUP Search Responses
+
+ In response to the client's LCUP request, the server returns zero or
+ more SearchResultEntry or SearchResultReference PDUs that fit the
+ client's specification, followed by a SearchResultDone PDU. The
+ behavior is as specified in [RFC2251 Section 4.5]. Each
+ SearchResultEntry or SearchResultReference PDU also contains a Sync
+ Update control that describes the LCUP state of the returned entry.
+ The SearchResultDone PDU contains a Sync Done control. The following
+ sections specify behaviors in addition to [RFC2251 Section 4.5].
+
+
+
+
+
+
+Megginson, et al. Standards Track [Page 10]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+4.2.1 Sync Update Informational Responses
+
+ The server may use the Sync Update control to return information not
+ related to a particular entry. It MAY do this at any time to return
+ a cookie to the client, or to inform the client that the sync phase
+ of a syncAndPersist search is complete and the persist phase has
+ begun. It MAY do this during the persist phase even though no entry
+ has changed that would have normally triggered a response. In order
+ to do this, it is REQUIRED to return the following:
+
+ - A SearchResultEntry PDU with the objectName field set to the DN of
+ the baseObject of the search request and with an empty attribute
+ list.
+
+ - A Sync Update control value with the fields set to the following:
+
+ stateUpdate - MUST be set to TRUE
+ entryUUID - SHOULD be set to the UUID of the baseObject of the
+ search request
+ entryLeftSet - MUST be set to FALSE
+ persistPhase - MUST be FALSE if the search is in the sync phase of a
+ request, and MUST be TRUE if the search is in the
+ persist phase
+ UUIDAttribute - SHOULD only be set if this is either the first result
+ returned or if the attribute has changed
+ scheme - MUST be set if the cookie is set and the cookie
+ format has changed; otherwise, it MAY be omitted
+ cookie - SHOULD be set
+
+ If the server merely wants to return a cookie to the client, it
+ should return as above with the cookie field set.
+
+ During a syncAndPersist request, the server MUST return (as above)
+ immediately after the last entry of the sync phase has been sent and
+ before the first entry of the persist phase has been sent. In this
+ case, the persistPhase field MUST be set to TRUE. This allows the
+ client to know that the sync phase is complete and the persist phase
+ is starting.
+
+4.2.2 Cookie Return Frequency
+
+ The cookie field of the Sync Update control value MAY be set in any
+ returned result, during both the sync phase and the persist phase.
+ The server should return the cookie to the client often enough for
+ the client to resync in a reasonable period of time in case the
+ search is disconnected or otherwise terminated. The
+ sendCookieInterval field in the Sync Request control is a suggestion
+
+
+
+
+Megginson, et al. Standards Track [Page 11]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+ to the server of how often to return the cookie in the Sync Update
+ control. The server SHOULD respect this value.
+
+ The scheme field of the Sync Update control value MUST be set if the
+ cookie is set and the cookie format has changed; otherwise, it MAY be
+ omitted.
+
+ Some clients may have unreliable connections, for example, a wireless
+ device or a WAN connection. These clients may want to insure that
+ the cookie is returned often in the Sync Update control value, so
+ that if they have to reconnect, they do not have to process many
+ redundant entries. These clients should set the sendCookieInterval
+ in the Sync Request control value to a low number, perhaps even 1.
+ Some clients may have a limited bandwidth connection, and may not
+ want to receive the cookie very often, or even at all (however, the
+ cookie is always sent back in the Sync Done control value upon
+ successful completion). These clients should set the
+ sendCookieInterval in the Sync Request control value to a high
+ number.
+
+ A reasonable behavior of the server is to return the cookie only when
+ data in the LCUP context has changed, even if the client has
+ specified a frequent sendCookieInterval. If nothing has changed, the
+ server can probably save some bandwidth by not returning the cookie.
+
+4.2.3. Definition of an Entry That Has Entered the Result Set
+
+ An entry SHALL BE considered to have entered the client's search
+ result set if one of the following conditions is met:
+
+ - During the sync phase for an incremental sync operation, the entry
+ is present in the search result set but was not present before;
+ this can be due to the entry being added via an LDAP Add
+ operation, or by the entry being moved into the result set by an
+ LDAP Modify DN operation, or by some modification to the entry
+ that causes it to enter the result set (e.g., adding an attribute
+ value that matches the clients search filter), or by some meta-
+ data change that causes the entry to enter the result set (e.g.,
+ relaxing of some access control that permits the entry to be
+ visible to the client).
+
+ - During the persist phase for a persistent search operation, the
+ entry enters the search result set; this can be due to the entry
+ being added via an LDAP Add operation, or by the entry being moved
+ into the result set by an LDAP Modify DN operation, or by some
+ modification to the entry that causes it to enter the result set
+ (e.g., adding an attribute value that matches the clients search
+ filter), or by some meta-data change that causes the entry to
+
+
+
+Megginson, et al. Standards Track [Page 12]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+ enter the result set (e.g., relaxing of some access control that
+ permits the entry to be visible to the client).
+
+4.2.4. Definition of an Entry That Has Changed
+
+ An entry SHALL BE considered to be changed if one or more of the
+ attributes in the attribute list in the search request have been
+ modified. For example, if the search request listed the attributes
+ "cn sn uid", and there is an entry in the client's search result set
+ with the "cn" attribute that has been modified, the entry is
+ considered to be modified. The modification may be due to an LDAP
+ Modify operation or by some change to the meta-data for the entry
+ (e.g., virtual attributes) that causes some change to the value of
+ the specified attributes.
+
+ The converse of this is that an entry SHALL NOT BE considered to be
+ changed if none of the attributes in the attribute list of the search
+ request are modified attributes of the entry. For example, if the
+ search request listed the attributes "cn sn uid", and there is an
+ entry in the client's search result set with the "foo" attribute that
+ has been modified, and none of the "cn" or "sn" or "uid" attributes
+ have been modified, the entry is NOT considered to be changed.
+
+4.2.5. Definition of an Entry That Has Left the Result Set
+
+ An entry SHALL BE considered to have left the client's search result
+ set if one of the following conditions is met:
+
+ - During the sync phase for an incremental sync operation, the entry
+ is not present in the search result set but was present before;
+ this can be due to the entry being deleted via an LDAP Delete
+ operation, or by the entry leaving the result set via an LDAP
+ Modify DN operation, or by some modification to the entry that
+ causes it to leave the result set (e.g., changing/removing an
+ attribute value so that it no longer matches the client's search
+ filter), or by some meta-data change that causes the entry to
+ leave the result set (e.g., adding of some access control that
+ denies the entry to be visible to the client).
+
+ - During the persist phase for a persistent search operation, the
+ entry leaves the search result set; this can be due to the entry
+ being deleted via an LDAP Delete operation, or by the entry
+ leaving the result set via an LDAP Modify DN operation, or by some
+ modification to the entry that causes it to leave the result set
+ (e.g., changing/removing an attribute value so that it no longer
+ matches the client's search filter), or by some meta-data change
+
+
+
+
+
+Megginson, et al. Standards Track [Page 13]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+ that causes the entry to leave the result set (e.g., adding of
+ some access control that denies the entry to be visible to the
+ client).
+
+4.2.6. Results For Entries Present in the Result Set
+
+ An entry SHOULD be returned as present under the following
+ conditions:
+
+ - The request is an initial synchronization or full resync request
+ and the entry is present in the client's search result set
+
+ - The request is an incremental synchronization and the entry has
+ changed or entered the result set since the last sync
+
+ - The search is in the persist phase and the entry enters the result
+ set or changes
+
+ For a SearchResultEntry return, the fields of the Sync Update control
+ value MUST be set as follows:
+
+ stateUpdate - MUST be set to FALSE
+ entryUUID - MUST be set to the UUID of the entry
+ entryLeftSet - MUST be set to FALSE
+ persistPhase - MUST be set to FALSE if during the sync phase or TRUE
+ if during the persist phase
+ UUIDAttribute - SHOULD only be set if this is either the first result
+ returned or if the attribute has changed
+ scheme - as above
+ cookie - as above
+
+ The searchResultReference return will look the same, except that the
+ entryUUID is not required. If it is specified, it MUST contain the
+ UUID of the DSE holding the reference knowledge.
+
+4.2.7. Results For Entries That Have Left the Result Set
+
+ An entry SHOULD be returned as having left the result set under the
+ following conditions:
+
+ - The request is an incremental synchronization during the sync
+ phase and the entry has left the result set
+
+ - The search is in the persist phase and the entry has left the
+ result set
+
+
+
+
+
+
+Megginson, et al. Standards Track [Page 14]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+ - The entry has left the result set as a result of an LDAP Delete or
+ LDAP Modify DN operation against the entry itself (i.e., not as a
+ result of an operation against its parent or ancestor)
+
+ For a SearchResultEntry return where the entry has left the result
+ set, the fields of the Sync Update control value MUST be set as
+ follows:
+
+ stateUpdate - MUST be set to FALSE
+ entryUUID - MUST be set to the UUID of the entry that left the
+ result set
+ entryLeftSet - MUST be set to TRUE
+ persistPhase - MUST be set to FALSE if during the sync phase or TRUE
+ if during the persist phase
+ UUIDAttribute - SHOULD only be set if this is either the first result
+ returned or if the attribute has changed
+ scheme - as above
+ cookie - as above
+
+ The searchResultReference return will look the same, except that the
+ entryUUID is not required. If it is specified, it MUST contain the
+ UUID of the DSE holding the reference knowledge.
+
+ Some server implementations keep track of deleted entries using a
+ tombstone - a hidden entry that keeps track of the state, but not all
+ of the data, of an entry that has been deleted. In this case, the
+ tombstone may not contain all of the original attributes of the
+ entry, and therefore it may be impossible for the server to determine
+ if an entry should be removed from the result set based on the
+ attributes in the client's search request. Servers SHOULD keep
+ enough information about the attributes in the deleted entries to
+ determine if an entry should be removed from the result set. Since
+ this may not be possible, the server MAY return an entry as having
+ left the result set even if it is not or never was in the client's
+ result set. Clients MUST ignore these notifications.
+
+4.3. Responses Requiring Special Consideration
+
+ The following sections describe special handling that may be required
+ when returning results.
+
+4.3.1. Returning Results During the Persistent Phase
+
+ During the persistent phase, the server SHOULD return the changed
+ entries to the client as quickly as possible.
+
+
+
+
+
+
+Megginson, et al. Standards Track [Page 15]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+4.3.2. No Mixing of Sync Phase with Persist Phase
+
+ During a sync phase, the server MUST NOT return any entries with the
+ persistPhase flag set to TRUE, and during the persist phase, all
+ entries returned MUST have the persistPhase flag set to TRUE. The
+ server MUST NOT mix and match sync phase entries with persist phase
+ entries. If there are any sync phase entries to return, they MUST be
+ returned before any persist phase entries are returned.
+
+4.3.3. Returning Updated Results During the Sync Phase
+
+ There may be updates to the entries in the result set of a sync phase
+ search during the actual search operation. If the DSA is under a
+ heavy update load, and it attempts to send all of those updated
+ entries to the client in addition to the other updates it was already
+ planning to send for the sync phase, the server may never get to the
+ end of the sync phase. Therefore, it is left up to the discretion of
+ the server implementation to decide when the client is "in sync" -
+ that is, when to end a syncOnly request, or when to send the Sync
+ Update Informational Response between the sync phase and the persist
+ phase of a syncAndPersist request. The server MAY send the same
+ entry multiple times during the sync phase if the entry changes
+ during the sync phase.
+
+ A reasonable behavior is for the server to generate a cookie based on
+ the server state at the time the client initiated the LCUP request,
+ and only send entries up to that point during the sync phase. Entries
+ updated after that point will be returned only during the persist
+ phase of a syncAndPersist request, or only upon an incremental
+ synchronization.
+
+4.3.4. Operational Attributes and Administrative Entries
+
+ An operational attribute SHOULD be returned if it is specified in the
+ attributes list and would normally be returned as subject to the
+ constraints of [RFC2251 Section 4.5]. If the server does not support
+ syncing of operational attributes, the server MUST return a
+ SearchResultDone message with a resultCode of unwillingToPerform.
+
+ LDAP Subentries [RFC3672] SHOULD be returned if they would normally
+ be returned by the search request. If the server does not support
+ syncing of LDAP Subentries, and the server can determine from the
+ search request that the client has requested LDAP Subentries to be
+ returned (e.g., search control or search filter), the server MUST
+ return a SearchResultDone message with a resultCode of
+ unwillingToPerform. Otherwise, the server MAY simply omit returning
+ LDAP Subentries.
+
+
+
+
+Megginson, et al. Standards Track [Page 16]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+4.3.5. Virtual Attributes
+
+ An entry may have attributes whose presence in the entry, or presence
+ of values of the attribute, is generated on the fly, possibly by some
+ mechanism outside of the entry, elsewhere in the DIT. An example of
+ this is collective attributes [RFC3671]. These attributes shall be
+ referred to in this document as virtual attributes.
+
+ LCUP treats these attributes the same way as normal, non-virtual
+ attributes. A virtual attribute SHOULD be returned if it is
+ specified in the attributes list and would normally be returned as
+ subject to the constraints of [RFC2251 Section 4.5]. If the server
+ does not support syncing of virtual attributes, the server MUST
+ return a SearchResultDone message with a resultCode of
+ unwillingToPerform.
+
+ One consequence of this is that if you change the definition of a
+ virtual attribute such that it makes the value of that attribute
+ change in many entries in the client's search scope, this means that
+ a server may have to return many entries to the client as a result of
+ that one change. It is not anticipated that this will be a frequent
+ occurrence, and the server has the option to simply force the client
+ to resync if necessary.
+
+ It is also possible that a future LDAP control will allow the client
+ to request only virtual or only non-virtual attributes.
+
+4.3.6. Modify DN and Delete Operations Applied to Subtrees
+
+ There is a special case where a Modify DN or a Delete operation is
+ applied to the base entry of a subtree, and either that base entry or
+ entries in the subtree are within the scope of an LCUP search
+ request. In this case, all of the entries in the subtree are
+ implicitly renamed or removed.
+
+ In either of these cases, the server MUST do one of the following:
+
+ - treat all of these entries as having been renamed or removed and
+ return each entry to the client as such
+
+ - decide that this would be prohibitively expensive, and force the
+ client to resync
+
+ If the search base object has been renamed, and the client has
+ received a noSuchObject as the result of a search request, the client
+ MAY use the entryUUID and UUIDAttribute to locate the new DN that is
+ the result of the modify DN operation.
+
+
+
+
+Megginson, et al. Standards Track [Page 17]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+4.3.7. Convergence Guarantees
+
+ If at any time during an LCUP search, either during the sync phase or
+ the persist phase, the server determines that it cannot guarantee
+ that it can bring the client's copy of the data to eventual
+ convergence, it SHOULD immediately terminate the LCUP search request
+ and return a SearchResultDone message with a resultCode of
+ lcupReloadRequired. This can also happen at the beginning of an
+ incremental synchronization request, if the client presents a cookie
+ that is out of date or otherwise unable to be processed. The client
+ should then issue an initial synchronization request.
+
+ This can happen, for example, if the data on the server is reloaded,
+ or if there has been some change to the meta-data that makes it
+ impossible for the server to determine if a particular entry should
+ or should not be part of the search result set, or if the meta-data
+ change makes it too resource intensive for the server to calculate
+ the proper result set.
+
+ The server can also return lcupReloadRequired if it determines that
+ it would be more efficient for the client to perform a reload, for
+ example, if too many entries have changed and a simple reload would
+ be much faster.
+
+4.4. LCUP Search Termination
+
+4.4.1. Server Initiated Termination
+
+ When the server has successfully finished processing the client's
+ request, it attaches a Sync Done control to the SearchResultDone
+ message and sends it to the client. However, if the SearchResultDone
+ message contains a resultCode that is not success or canceled, the
+ Sync Done control MAY be omitted. Although the LCUP cookie is
+ OPTIONAL in the Sync Done control value, it MUST be set if the
+ SearchResultDone resultCode is success or canceled. The server
+ SHOULD also set the cookie if the resultCode is
+ lcupResourcesExhausted, timeLimitExceeded, sizeLimitExceeded, or
+ adminLimitExceeded. This allows the client to more easily resync
+ later. If some error occurred, either an LDAP search error (e.g.,
+ insufficientAccessRights) or an LCUP error (e.g.,
+ lcupUnsupportedScheme), the cookie MAY be omitted. If the cookie is
+ set, the scheme MUST be set also if the cookie format has changed,
+ otherwise, it MAY be omitted.
+
+ If server resources become tight, the server can terminate one or
+ more search operations by sending a SearchResultDone message to the
+ client(s) with a resultCode of lcupResourcesExhausted. The server
+ SHOULD attach a Sync Done control with the cookie set. A server side
+
+
+
+Megginson, et al. Standards Track [Page 18]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+ policy is used to decide which searches to terminate. This can also
+ be used as a security mechanism to disconnect clients that are
+ suspected of malicious actions, but if the server can infer that the
+ client is malicious, the server SHOULD return lcupSecurityViolation
+ instead.
+
+4.4.2. Client Initiated Termination
+
+ If the client needs to terminate the synchronization process and it
+ wishes to obtain the cookie that represents the current state of its
+ data, it issues an LDAP Cancel operation [RFC3909]. The server
+ responds immediately with a LDAP Cancel response [RFC3909]. The
+ server MAY send any pending SearchResultEntry or
+ SearchResultReference PDUs if the server cannot easily abort or
+ remove those search results from its outgoing queue. The server
+ SHOULD send as few of these remaining messages as possible. Finally,
+ the server sends the message SearchResultDone with the Sync Done
+ control attached. If the search was successful up to that point, the
+ resultCode field of the SearchResultDone message MUST be canceled
+ [RFC3909], and the cookie MUST be set in the Sync Done control. If
+ there is an error condition, the server MAY return as described in
+ section 4.4.1 above, or MAY return as described in [RFC3909].
+
+ If the client is not interested in the state information, it can
+ simply abandon the search operation or disconnect from the server.
+
+4.5. Size and Time Limits
+
+ The server SHALL support size and time limits as specified in
+ [RFC2251, Section 5]. The server SHOULD ensure that if the operation
+ is terminated due to these conditions, the cookie is sent back to the
+ client.
+
+4.6. Operations on the Same Connection
+
+ It is permissible for the client to issue other LDAP operations on
+ the connection used by the protocol. Since each LDAP
+ request/response carries a message id there will be no ambiguity
+ about which PDU belongs to which operation. By sharing the
+ connection among multiple operations, the server will be able to
+ conserve its resources.
+
+4.7. Interactions with Other Controls
+
+ LCUP defines neither restrictions nor guarantees about the ability to
+ use the controls defined in this document in conjunction with other
+ LDAP controls, except for the following: A server MAY ignore non-
+ critical controls supplied with the LCUP control. A server MAY
+
+
+
+Megginson, et al. Standards Track [Page 19]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+ ignore an LCUP defined control if it is non-critical and it is
+ supplied with other critical controls. If a server receives a
+ critical LCUP control with another critical control, and the server
+ does not support both controls at the same time, the server SHOULD
+ return unavailableCriticalExtension.
+
+ It is up to the server implementation to determine if the server
+ supports controls such as the Sort or VLV or similar controls that
+ change the order of the entries sent to the client. But note that it
+ may be difficult or impossible for a server to perform an incremental
+ synchronization in the presence of such controls, since the cookie
+ will typically be based off a change number, or Change Sequence
+ Number (CSN), or timestamp, or some criteria other than an
+ alphabetical order.
+
+4.8. Replication Considerations
+
+ Use of an LCUP cookie with multiple DSAs in a replicated environment
+ is not defined by LCUP. An implementation of LCUP may support
+ continuation of an LCUP session with another DSA holding a replica of
+ the LCUP context. Clients MAY submit cookies returned by one DSA to
+ a different DSA; it is up to the server to determine if a cookie is
+ one they recognize or not and to return an appropriate result code if
+ not.
+
+5. Client Side Considerations
+
+5.1. Using Cookies with Different Search Criteria
+
+ The cookie received from the server after a synchronization session
+ SHOULD only be used with the same search specification as the search
+ that generated the cookie. Some servers MAY allow the cookie to be
+ used with a more restrictive search specification than the search
+ that generated the cookie. If the server does not support the
+ cookie, it MUST return lcupInvalidCookie. This is because the client
+ can end up with an incomplete data store otherwise. A more
+ restrictive search specification is one that would generate a subset
+ of the data produced by the original search specification.
+
+5.2. Renaming the Base Object
+
+ Because an LCUP client specifies the area of the tree with which it
+ wishes to synchronize through the standard LDAP search specification,
+ the client can be returned noSuchObject error if the root of the
+ synchronization area was renamed between the synchronization sessions
+ or during a synchronization session. If this condition occurs, the
+ client can attempt to locate the root by using the root's UUID saved
+ in client's local data store. It then can repeat the synchronization
+
+
+
+Megginson, et al. Standards Track [Page 20]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+ request using the new search base. In general, a client can detect
+ that an entry was renamed and apply the changes received to the right
+ entry by using the UUID rather than DN based addressing.
+
+5.3. Use of Persistent Searches With Respect to Resources
+
+ Each active persistent operation requires that an open TCP connection
+ be maintained between an LDAP client and an LDAP server that might
+ not otherwise be kept open. Therefore, client implementors are
+ encouraged to avoid using persistent operations for non-essential
+ tasks and to close idle LDAP connections as soon as practical. The
+ server may close connections if server resources become tight.
+
+5.4. Continuation References to Other LCUP Contexts
+
+ The client MAY receive a continuation reference
+ (SearchResultReference [RFC2251 SECTION 4.5.3]) if the search request
+ spans multiple parts of the DIT, some of which may require a
+ different LCUP cookie, some of which may not even be managed by LCUP.
+ The client SHOULD maintain a cache of the LDAP URLs returned in the
+ continuation references and the cookies associated with them. The
+ client is responsible for performing another LCUP search to follow
+ the references, and SHOULD use the cookie corresponding to the LDAP
+ URL for that reference (if it has a cookie).
+
+5.5. Referral Handling
+
+ The client may receive a referral (Referral [RFC2251 SECTION 4.1.11])
+ when the search base is a subordinate reference, and this will end
+ the operation.
+
+5.6. Multiple Copies of Same Entry During Sync Phase
+
+ The server MAY send the same entry multiple times during a sync phase
+ if the entry changes during the sync phase. The client SHOULD use
+ the last sent copy of the entry as the current one.
+
+5.7. Handling Server Out of Resources Condition
+
+ If the client receives an lcupResourcesExhausted or
+ lcupSecurityViolation resultCode, the client SHOULD wait at least 5
+ seconds before attempting another operation. It is RECOMMENDED that
+ the client use an exponential backoff strategy, but different clients
+ may want to use different backoff strategies.
+
+
+
+
+
+
+
+Megginson, et al. Standards Track [Page 21]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+6. Server Implementation Considerations
+
+6.1. Server Support for UUIDs
+
+ Servers MUST support UUIDs. UUIDs are required in the Sync Update
+ control. Additionally, server implementers SHOULD make the UUID
+ values for the entries available as an attribute of the entry, and
+ provide indexing or other mechanisms to allow clients to search for
+ an entry using the UUID attribute in the search filter. The
+ syncUpdate control provides a field UUIDAttribute to allow the server
+ to let the client know the name or OID of the attribute to use to
+ search for an entry by UUID.
+
+6.2. Example of Using an RUV as the Cookie Value
+
+ By design, the protocol supports multiple cookie schemes. This is to
+ allow different implementations the flexibility of storing any
+ information applicable to their environment. A reasonable
+ implementation for an LDUP compliant server would be to use the
+ Replica Update Vector (RUV). For each master, RUV contains the
+ largest CSN seen from this master. In addition, RUV implemented by
+ some directory servers (not yet in LDUP) contains replica generation
+ - an opaque string that identifies the replica's data store. The
+ replica generation value changes whenever the replica's data is
+ reloaded. Replica generation is intended to signal the
+ replication/synchronization peers that the replica's data was
+ reloaded and that all other replicas need to be reinitialized. RUV
+ satisfies the three most important properties of the cookie: (1) it
+ uniquely identifies the state of client's data, (2) it can be used to
+ synchronize with multiple servers, and (3) it can be used to detect
+ that the server's data was reloaded. If RUV is used as the cookie,
+ entries last modified by a particular master must be sent to the
+ client in the order of their last modified CSN. This ordering
+ guarantees that the RUV can be updated after each entry is sent.
+
+6.3. Cookie Support Issues
+
+6.3.1. Support for Multiple Cookie Schemes
+
+ A server may support one or more LCUP cookie schemes. It is expected
+ that schemes will be published along with their OIDs as RFCs. The
+ server's DIT may be partitioned into different sections which may
+ have different cookies associated with them. For example, some
+ servers may use some sort of replication mechanism to support LCUP.
+ If so, the DIT may be partitioned into multiple replicas. A client
+ may send an LCUP search request that spans multiple replicas. Some
+ parts of the DIT spanned by the search request scope may support LCUP
+ and some may not. The server MUST send a SearchResultReference
+
+
+
+Megginson, et al. Standards Track [Page 22]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+ [RFC2251, SECTION 4.5.3] when the LCUP Context for a returned entry
+ changes. The server SHOULD send all references to other LCUP
+ Contexts in the search scope first, in order to allow the clients to
+ process these searches in parallel. The LDAP URL(s) returned MUST
+ contain the DN(s) of the base of another section of the DIT (however
+ the server implementation has partitioned the DIT). The client will
+ then issue another LCUP search using the LDAP URL returned. Each
+ section of the DIT MAY require a different cookie value, so the
+ client SHOULD maintain a cache, mapping the different LDAP URL values
+ to different cookies. If the cookie changes, the scheme may change
+ as well, but the cookie scheme MUST be the same within a given LCUP
+ Context.
+
+6.3.2. Information Contained in the Cookie
+
+ The cookie must contain enough information to allow the server to
+ determine whether the cookie can be safely used with the search
+ specification it is attached to. As discussed earlier in the
+ document, the cookie SHOULD only be used with the search
+ specification that is equal to the one for which the cookie was
+ generated, but some servers MAY support using a cookie with a search
+ specification that is more restrictive than the one used to generate
+ the cookie.
+
+6.4. Persist Phase Response Time
+
+ The specification makes no guarantees about how soon a server should
+ send notification of a changed entry to the client during the persist
+ phase. This is intentional as any specific maximum delay would be
+ impossible to meet in a distributed directory service implementation.
+ Server implementers are encouraged to minimize the delay before
+ sending notifications to ensure that clients' needs for timeliness of
+ change notification are met.
+
+6.5. Scaling Considerations
+
+ Implementers of servers that support the mechanism described in this
+ document should ensure that their implementation scales well as the
+ number of active persistent operations and the number of changes made
+ in the directory increases. Server implementers are also encouraged
+ to support a large number of client connections if they need to
+ support large numbers of persistent operations.
+
+
+
+
+
+
+
+
+
+Megginson, et al. Standards Track [Page 23]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+6.6. Alias Dereferencing
+
+ LCUP design does not consider issues associated with alias
+ dereferencing in search. Clients MUST specify derefAliases as either
+ neverDerefAliases or derefFindingBaseObj. Servers are to return
+ protocolError if the client specifies either derefInSearching or
+ derefAlways.
+
+7. Synchronizing Heterogeneous Data Stores
+
+ Clients, like a meta directory join engine, synchronizing multiple
+ writable data stores, will only work correctly if each piece of
+ information comes from a single authoritative data source. In a
+ replicated environment, an LCUP Context should employ the same
+ conflict resolution scheme across all its replicas. This is because
+ different systems have different notions of time and different update
+ resolution procedures. As a result, a change applied on one system
+ can be discarded by the other, thus preventing the data stores from
+ converging.
+
+8. IANA Considerations
+
+ This document lists several values that have been registered by the
+ IANA. The following LDAP result codes have been assigned by IANA as
+ described in section 3.6 of [RFC3383]:
+
+ lcupResourcesExhausted 113
+ lcupSecurityViolation 114
+ lcupInvalidData 115
+ lcupUnsupportedScheme 116
+ lcupReloadRequired 117
+
+ The three controls defined in this document have been registered as
+ LDAP Protocol Mechanisms as described in section 3.2 of [RFC3383].
+ One OID, 1.3.6.1.1.7, has been assigned by IANA as described in
+ section 3.1 of [RFC3383]. The OIDs for the controls defined in this
+ document are derived as follows from the one assigned by IANA:
+
+ LCUP Sync Request Control 1.3.6.1.1.7.1
+ LCUP Sync Update Control 1.3.6.1.1.7.2
+ LCUP Sync Done Control 1.3.6.1.1.7.3
+
+9. Security Considerations
+
+ In some situations, it may be important to prevent general exposure
+ of information about changes that occur in an LDAP server. Therefore,
+ servers that implement the mechanism described in this document
+ SHOULD provide a means to enforce access control on the entries
+
+
+
+Megginson, et al. Standards Track [Page 24]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+ returned and MAY also provide specific access control mechanisms to
+ control the use of the controls and extended operations defined in
+ this document.
+
+ As with normal LDAP search requests, a malicious client can initiate
+ a large number of persistent search requests in an attempt to consume
+ all available server resources and deny service to legitimate
+ clients. The protocol provides the means to stop malicious clients
+ by disconnecting them from the server. The servers that implement
+ the mechanism SHOULD provide the means to detect the malicious
+ clients. In addition, the servers SHOULD provide the means to limit
+ the number of resources that can be consumed by a single client.
+
+10. References
+
+10.1. Normative References
+
+ [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
+ Requirement Levels", BCP 14, RFC 2119, March 1997.
+
+ [RFC2251] Wahl, M., Howes, T., and S. Kille, "Lightweight
+ Directory Access Protocol (v3)", RFC 2251, December
+ 1997.
+
+ [RFC3383] Zeilenga, K., "Internet Assigned Numbers Authority
+ (IANA) Considerations for Lightweight Directory Access
+ Protocol (LDAP)", BCP 64, RFC 3383, September 2002.
+
+ [RFC3909] Zeilenga, K., "Lightweight Directory Access Protocol
+ (LDAP) Cancel Operation", RFC 3909, October 2004.
+
+ [X.680] ITU-T, "Abstract Syntax Notation One (ASN.1) -
+ Specification of Basic Notation", X.680, 1994.
+
+ [X.690] ITU-T, "Specification of ASN.1 encoding rules: Basic,
+ Canonical, and Distinguished Encoding Rules", X.690,
+ 1994.
+
+ [UUID] International Organization for Standardization (ISO),
+ "Information technology - Open Systems Interconnection -
+ Remote Procedure Call", ISO/IEC 11578:1996.
+
+
+
+
+
+
+
+
+
+
+Megginson, et al. Standards Track [Page 25]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+10.2. Informative References
+
+ [RFC3384] Stokes, E., Weiser, R., Moats, R., and R. Huber,
+ "Lightweight Directory Access Protocol (version 3)
+ Replication Requirements", RFC 3384, October 2002.
+
+ [RFC3671] Zeilenga, K., "Collective Attributes in the Lightweight
+ Directory Access Protocol (LDAP)", RFC 3671, December
+ 2003.
+
+ [RFC3672] Zeilenga, K. and S. Legg, "Subentries in the Lightweight
+ Directory Access Protocol (LDAP)", RFC 3672, December
+ 2003.
+
+11. Acknowledgments
+
+ The LCUP protocol is based in part on the Persistent Search Change
+ Notification Mechanism defined by Mark Smith, Gordon Good, Tim Howes,
+ and Rob Weltman, the LDAPv3 Triggered Search Control defined by Mark
+ Wahl, and the LDAP Control for Directory Synchronization defined by
+ Michael Armijo. The members of the IETF LDUP working group made
+ significant contributions to this document.
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+Megginson, et al. Standards Track [Page 26]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+Appendix - Features Left Out of LCUP
+
+ There are several features present in other protocols or considered
+ useful by clients that are currently not included in the protocol
+ primarily because they are difficult to implement on the server.
+ These features are briefly discussed in this section.
+
+Triggered Search Change Type
+
+ This feature is present in the Triggered Search specification. A
+ flag is attached to each entry returned to the client indicating the
+ reason why this entry is returned. The possible reasons from the
+ document are:
+
+ - notChange: the entry existed in the directory and matched the
+ search at the time the operation is being performed,
+
+ - enteredSet: the entry entered the result,
+
+ - leftSet: the entry left the result,
+
+ - modified: the entry was part of the result set, was modified or
+ renamed, and still is in the result set.
+
+ The leftSet feature is particularly useful because it indicates to
+ the client that an entry is no longer within the client's search
+ specification and the client can remove the associated data from its
+ data store. Ironically, this feature is the hardest to implement on
+ the server because the server does not keep track of the client's
+ state and has no easy way of telling which entries moved out of scope
+ between synchronization sessions with the client. A compromise could
+ be reached by only providing this feature for the operations that
+ occur while the client is connected to the server. This is easier to
+ accomplish because the decision about the change type can be made
+ based only on the change without need for any historical information.
+ This, however, would add complexity to the protocol.
+
+Persistent Search Change Type
+
+ This feature is present in the Persistent Search specification.
+ Persistent search has the notion of changeTypes. The client
+ specifies which type of updates will cause entries to be returned,
+ and optionally whether the server tags each returned entry with the
+ type of change that caused that entry to be returned.
+
+ For LCUP, the intention is full synchronization, not partial. Each
+ entry returned by an LCUP search will have some change associated
+ with it that may concern the client. The client may have to have a
+
+
+
+Megginson, et al. Standards Track [Page 27]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+ local index of entries by DN or UUID to determine if the entry has
+ been added or just modified. It is easy for clients to determine if
+ the entry has been deleted because the entryLeftSet value of the Sync
+ Update control will be TRUE.
+
+Sending Changes
+
+ Some earlier synchronization protocols sent the client(s) only the
+ modified attributes of the entry rather than the entire entry. While
+ this approach can significantly reduce the amount of data returned to
+ the client, it has several disadvantages. First, unless a separate
+ mechanism (like the change type described above) is used to notify
+ the client about entries moving into the search scope, sending only
+ the changes can result in the client having an incomplete version of
+ the data. Let's consider an example. An attribute of an entry is
+ modified. As a result of the change, the entry enters the scope of
+ the client's search. If only the changes are sent, the client would
+ never see the initial data of the entry. Second, this feature is
+ hard to implement since the server might not contain sufficient
+ information to construct the changes based solely on the server's
+ state and the client's cookie. On the other hand, this feature can
+ be easily implemented by the client assuming that the client has the
+ previous version of the data and can perform value by value
+ comparisons.
+
+Data Size Limits
+
+ Some earlier synchronization protocols allowed clients to control the
+ amount of data sent to them in the search response. This feature was
+ intended to allow clients with limited resources to process
+ synchronization data in batches. However, an LDAP search operation
+ already provides the means for the client to specify the size limit
+ by setting the sizeLimit field in the SearchRequest to the maximum
+ number of entries the client is willing to receive. While the
+ granularity is not the same, the assumption is that regular LDAP
+ clients that can deal with the limitations of the LDAP protocol will
+ implement LCUP.
+
+Data Ordering
+
+ Some earlier synchronization protocols allowed a client to specify
+ that parent entries should be sent before the children for add
+ operations and children entries sent before their parents during
+ delete operations. This ordering helps clients to maintain a
+ hierarchical view of the data in their data store. While possibly
+ useful, this feature is relatively hard to implement and is expensive
+ to perform.
+
+
+
+
+Megginson, et al. Standards Track [Page 28]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+Authors' Addresses
+
+ Rich Megginson
+ Netscape Communications Corp., an America Online company.
+ 360 W. Caribbean Drive
+ Sunnyvale, CA 94089
+ USA
+
+ Phone: +1 505 797-7762
+ EMail: rmegginson0224@aol.com
+
+
+ Olga Natkovich
+ Yahoo, Inc.
+ 701 First Ave.
+ Sunnyvale, CA 94089
+ USA
+
+ Phone: +1 408 349-6153
+ EMail: olgan@yahoo-inc.com
+
+
+ Mark Smith
+ Pearl Crescent, LLC
+ 447 Marlpool Drive
+ Saline, MI 48176
+ USA
+
+ Phone: +1 734 944-2856
+ EMail: mcs@pearlcrescent.com
+
+
+ Jeff Parham
+ Microsoft Corporation
+ One Microsoft Way
+ Redmond, WA 98052-6399
+ USA
+
+ Phone: +1 425 882-8080
+ EMail: jeffparh@microsoft.com
+
+
+
+
+
+
+
+
+
+
+
+Megginson, et al. Standards Track [Page 29]
+\f
+RFC 3928 LDAP Client Update Protocol October 2004
+
+
+Full Copyright Statement
+
+ Copyright (C) The Internet Society (2004).
+
+ This document is subject to the rights, licenses and restrictions
+ contained in BCP 78, and at www.rfc-editor.org, and except as set
+ forth therein, the authors retain all their rights.
+
+ This document and the information contained herein are provided on an
+ "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
+ OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
+ ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
+ INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
+ INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
+ WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
+
+Intellectual Property
+
+ The IETF takes no position regarding the validity or scope of any
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+
+ Copies of IPR disclosures made to the IETF Secretariat and any
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+ http://www.ietf.org/ipr.
+
+ The IETF invites any interested party to bring to its attention any
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+
+Acknowledgement
+
+ Funding for the RFC Editor function is currently provided by the
+ Internet Society.
+
+
+
+
+
+
+
+Megginson, et al. Standards Track [Page 30]
+\f
projects / openldap / commitdiff