-
Internet-Draft Editor: J. Sermersheim
Intended Category: Standard Track Novell, Inc
-Document: draft-ietf-ldapbis-protocol-22.txt Feb 2004
-Obsoletes: RFC 2251, 2830, [LIMR]
+Document: draft-ietf-ldapbis-protocol-30.txt Feb 2005
+Obsoletes: RFCs 2251, 2830, 3771
LDAP: The Protocol
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 an Internet-Draft and is subject to all provisions
+ 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.
+
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."
+ 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-
+ ldapbis@openldap.org>. Please send editorial comments directly to the
+ editor <jimse@novell.com>.
- Distribution of this memo is unlimited. Technical discussion of this
- document will take place on the IETF LDAP Revision Working Group
- (LDAPbis) mailing list <ietf-ldapbis@openldap.org>. Please send
- editorial comments directly to the editor <jimse@novell.com>.
+Copyright Notice
+ Copyright (C) The Internet Society 2004. All Rights Reserved.
+
Abstract
This document describes the protocol elements, along with their
elements are based on those described in the X.500 Directory Access
Protocol (DAP).
+
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+
Table of Contents
- 1. Introduction....................................................2
- 1.1. Relationship to Obsolete Specifications.......................3
+ 1. Introduction....................................................3
+ 1.1. Relationship to Other LDAP Specifications.....................3
2. Conventions.....................................................3
- 3. Protocol Model..................................................3
- 4. Elements of Protocol............................................4
- 4.1. Common Elements...............................................4
+ 3. Protocol Model..................................................4
+ 3.1 Operation and LDAP Message Layer Relationship..................5
+ 4. Elements of Protocol............................................5
+ 4.1. Common Elements...............................................5
4.1.1. Message Envelope............................................5
- 4.1.2. String Types................................................6
+ 4.1.2. String Types................................................7
+ 4.1.3. Distinguished Name and Relative Distinguished Name..........7
+ 4.1.4. Attribute Descriptions......................................8
+ 4.1.5. Attribute Value.............................................8
+ 4.1.6. Attribute Value Assertion...................................8
+ 4.1.7. Attribute and PartialAttribute..............................9
+ 4.1.8. Matching Rule Identifier....................................9
+ 4.1.9. Result Message..............................................9
+ 4.1.10. Referral..................................................11
+ 4.1.11. Controls..................................................13
+ 4.2. Bind Operation...............................................14
+ 4.3. Unbind Operation.............................................17
+ 4.4. Unsolicited Notification.....................................17
+ 4.5. Search Operation.............................................18
+ 4.6. Modify Operation.............................................29
+ 4.7. Add Operation................................................31
+ 4.8. Delete Operation.............................................31
+ 4.9. Modify DN Operation..........................................32
+ 4.10. Compare Operation...........................................33
+ 4.11. Abandon Operation...........................................34
+ 4.12. Extended Operation..........................................35
+ 4.13. IntermediateResponse Message................................36
+ 4.14. StartTLS Operation..........................................37
+ 5. Protocol Encoding, Connection, and Transfer....................39
+ 5.1. Protocol Encoding............................................40
+ 5.2. Transmission Control Protocol (TCP)..........................40
+ 5.3. Termination of the LDAP session..............................40
+ 6. Security Considerations........................................41
+ 7. Acknowledgements...............................................42
+ 8. Normative References...........................................42
+ 9. Informative References.........................................44
+ 10. IANA Considerations...........................................44
+ 11. Editor's Address..............................................45
+ Appendix A - LDAP Result Codes....................................46
+ A.1 Non-Error Result Codes........................................46
+ A.2 Result Codes..................................................46
+ Appendix B - Complete ASN.1 Definition............................51
+ Appendix C - Changes..............................................57
+ C.1 Changes made to RFC 2251:.....................................57
+ C.2 Changes made to RFC 2830:.....................................62
+ C.3 Changes made to RFC 3771:.....................................63
+
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Lightweight Directory Access Protocol Version 3
- 4.1.3. Distinguished Name and Relative Distinguished Name..........6
- 4.1.4. Attribute Descriptions......................................7
- 4.1.5. Attribute Value.............................................7
- 4.1.6. Attribute Value Assertion...................................7
- 4.1.7. Attribute and PartialAttribute..............................8
- 4.1.8. Matching Rule Identifier....................................8
- 4.1.9. Result Message..............................................8
- 4.1.10. Referral..................................................10
- 4.1.11. Controls..................................................11
- 4.2. Bind Operation...............................................13
- 4.3. Unbind Operation.............................................16
- 4.4. Unsolicited Notification.....................................16
- 4.5. Search Operation.............................................17
- 4.6. Modify Operation.............................................26
- 4.7. Add Operation................................................27
- 4.8. Delete Operation.............................................28
- 4.9. Modify DN Operation..........................................29
- 4.10. Compare Operation...........................................30
- 4.11. Abandon Operation...........................................31
- 4.12. Extended Operation..........................................31
- 4.13. IntermediateResponse Message................................33
- 4.13.1. Usage with LDAP ExtendedRequest and ExtendedResponse......33
- 4.13.2. Usage with LDAP Request Controls..........................34
- 4.14. StartTLS Operation..........................................34
- 5. Protocol Element Encodings and Transfer........................36
- 5.1. Protocol Encoding............................................37
- 5.2. Transfer Protocols...........................................37
- 6. Security Considerations........................................38
- 7. Acknowledgements...............................................39
- 8. Normative References...........................................39
- 9. Informative References.........................................41
- 10. IANA Considerations...........................................41
- 11. Editor's Address..............................................41
- Appendix A - LDAP Result Codes....................................42
- A.1 Non-Error Result Codes........................................42
- A.2 Result Codes..................................................42
- Appendix B - Complete ASN.1 Definition............................46
- Appendix C - Changes..............................................52
- C.1 Changes made to made to RFC 2251:.............................52
- C.2 Changes made to made to RFC 2830:.............................57
- C.3 Changes made to made to [LIMR]:...............................58
-
-
1. Introduction
The Directory is "a collection of open systems cooperating to provide
(DSA)). Clients interact with servers using a directory access
protocol.
-
-
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-
This document details the protocol elements of the Lightweight
Directory Access Protocol (LDAP), along with their semantics.
Following the description of protocol elements, it describes the way
in which the protocol elements are encoded and transferred.
-1.1. Relationship to Obsolete Specifications
+1.1. Relationship to Other LDAP Specifications
This document is an integral part of the LDAP Technical Specification
[Roadmap] which obsoletes the previously defined LDAP technical
remainder of RFC 2830 is obsoleted by [AuthMeth]. Appendix C.2
summarizes substantive changes to the remaining sections.
- This document also obsoletes [LIMR] in entirety.
- <<Note to RFC Editor: [LIMR] is to be replaced with the RFC
- number assigned to draft-rharrison-ldap-intermediate-resp-
- xx.txt, an RFC-to-be.>>
+ This document also obsoletes RFC 3771 in entirety.
2. Conventions
"SHOULD", "SHOULD NOT", "RECOMMENDED", and "MAY" in this document are
to be interpreted as described in [Keyword].
- The terms "connection" and "LDAP connection" both refer to the
- underlying transport protocol connection between two protocol peers.
+ 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>.
- The term "TLS connection" refers to a [TLS]-protected LDAP
- connection.
+ 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].
- The terms "association" and "LDAP association" both refer to the
- association of the LDAP connection and its current authentication and
- authorization state.
+
+
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+
+ The term "transport connection" refers to the underlying transport
+ services used to carry the protocol exchange, as well as associations
+ established by these services.
+
+ The term "TLS layer" refers to TLS services used in providing
+ security services, as well as associations established by these
+ services.
+
+ The term "SASL layer" refers to SASL services used in providing
+ security services, as well as associations established by these
+ services.
+
+ The term "LDAP message layer" refers to the LDAP Message (PDU)
+ services used in providing directory services, as well as
+ associations established by these services.
+
+ The term "LDAP session" refers to combined services (transport
+ connection, TLS layer, SASL layer, LDAP message layer) and their
+ associations.
+
+ See the table in Section 5 for an illustration of these four terms.
3. Protocol Model
The general model adopted by this protocol is one of clients
performing protocol operations against servers. In this model, a
client transmits a protocol request describing the operation to be
-
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-
performed to a server. The server is then responsible for performing
the necessary operation(s) in the Directory. Upon completion of an
operation, the server typically returns a response containing
appropriate data to the requesting client.
+ Protocol operations are generally independent of one another. Each
+ operation is processed as an atomic action, leaving the directory in
+ a consistent state.
+
Although servers are required to return responses whenever such
responses are defined in the protocol, there is no requirement for
synchronous behavior on the part of either clients or servers.
Requests and responses for multiple operations generally may be
- exchanged between a client and server in any order, provided the
- client eventually receives a response for every request that requires
- one.
+ exchanged between a client and server in any order. If required,
+ synchronous behavior may be controlled by client applications.
The core protocol operations defined in this document can be mapped
to a subset of the X.500 (1993) Directory Abstract Service [X.511].
implementations acting as a gateway to X.500 directories may need to
make multiple DAP requests to service a single LDAP request.
+
+
+
+
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+
+3.1 Operation and LDAP Message Layer Relationship
+ Protocol operations are exchanged at the LDAP message layer. When the
+ transport connection is closed, any uncompleted operations at the
+ LDAP message layer, when possible, are abandoned, and when not
+ possible, are completed without transmission of the response. Also,
+ when the transport connection is closed, the client MUST NOT assume
+ that any uncompleted update operations have succeeded or failed.
+
+
4. Elements of Protocol
The protocol is described using Abstract Syntax Notation One
([ASN.1]), and is transferred using a subset of ASN.1 Basic Encoding
- Rules ([BER]). Section 5.1 specifies how the protocol elements are
+ Rules ([BER]). Section 5 specifies how the protocol elements are
encoded and transferred.
In order to support future extensions to this protocol, extensibility
Changes to the protocol other than through the extension mechanisms
described here require a different version number. A client indicates
- the version it is using as part of the bind request, described in
- Section 4.2. If a client has not sent a bind, the server MUST assume
+ the version it is using as part of the BindRequest, described in
+ Section 4.2. If a client has not sent a Bind, the server MUST assume
the client is using version 3 or later.
- Clients may determine the protocol versions a server supports by
- reading the 'supportedLDAPVersion' attribute from the root DSE (DSA-
- Specific Entry) [Models].
+ Clients may attempt to determine the protocol versions a server
+ supports by reading the 'supportedLDAPVersion' attribute from the
+ root DSE (DSA-Specific Entry) [Models].
4.1. Common Elements
protocol operations.
-
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4.1.1. Message Envelope
For the purposes of protocol exchanges, all protocol operations are
encapsulated in a common envelope, the LDAPMessage, which is defined
as follows:
+
+
+
+
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LDAPMessage ::= SEQUENCE {
messageID MessageID,
protocolOp CHOICE {
abandonRequest AbandonRequest,
extendedReq ExtendedRequest,
extendedResp ExtendedResponse,
- intermediateResponse IntermediateResponse
- ... },
+ ...,
+ intermediateResponse IntermediateResponse },
controls [0] Controls OPTIONAL }
MessageID ::= INTEGER (0 .. maxInt)
The function of the LDAPMessage is to provide an envelope containing
common fields required in all protocol exchanges. At this time the
- only common fields are the message ID and the controls.
+ only common fields are the messageID and the controls.
If the server receives a PDU from the client in which the LDAPMessage
SEQUENCE tag cannot be recognized, the messageID cannot be parsed,
encoding structures or lengths of data fields are found to be
incorrect, then the server SHOULD return the Notice of Disconnection
described in Section 4.4.1, with the resultCode set to protocolError,
- and MUST immediately close the connection.
+ and MUST immediately terminate the LDAP session as described in
+ Section 5.3.
In other cases where the client or server cannot parse a PDU, it
- SHOULD abruptly close the connection where further communication
- (including providing notice) would be pernicious. Otherwise, server
+ SHOULD abruptly terminate the LDAP session (Section 5.3) where
+ further communication (including providing notice) would be
+ pernicious. Otherwise, server implementations MUST return an
+ appropriate response to the request, with the resultCode set to
+ protocolError.
+
+
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- implementations MUST return an appropriate response to the request,
- with the resultCode set to protocolError.
-
-
4.1.1.1. Message ID
All LDAPMessage envelopes encapsulating responses contain the
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 requests outstanding in the LDAP association
- of which this message is a part. The zero value is reserved for the
- unsolicited notification message.
+ the messageID of any other request in progress in the same LDAP
+ session. 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 session 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
completes). Otherwise the behavior is undefined. For this purpose,
- note that abandon and abandoned operations do not send responses.
+ note that Abandon and successfully abandoned operations do not send
+ responses.
4.1.2. String Types
An LDAPDN is defined to be the representation of a Distinguished Name
(DN) after encoding according to the specification in [LDAPDN].
-
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-
LDAPDN ::= LDAPString
-- Constrained to <distinguishedName> [LDAPDN]
+
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+
A RelativeLDAPDN is defined to be the representation of a Relative
Distinguished Name (RDN) after encoding according to the
The AttributeValueAssertion (AVA) type definition is similar to the
one in the X.500 Directory standards. It contains an attribute
- description and a matching rule ([Models Section 4.1.3) assertion
-
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-
+ description and a matching rule ([Models] Section 4.1.3) assertion
value suitable for that type. Elements of this type are typically
used to assert that the value in assertionValue matches a value of an
attribute.
+
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+
AttributeValueAssertion ::= SEQUENCE {
attributeDesc AttributeDescription,
...,
vals (SIZE(1..MAX))})
- No two attribute values are equivalent as described by Section 2.3 of
- [Models]. The set of attribute values is unordered. Implementations
- MUST NOT rely upon the ordering being repeatable.
+ No two of the attribute values may be equivalent as described by
+ Section 2.3 of [Models]. The set of attribute values is unordered.
+ Implementations MUST NOT rely upon the ordering being repeatable.
4.1.8. Matching Rule Identifier
The LDAPResult is the construct used in this protocol to return
success or failure indications from servers to clients. To various
- requests, servers will return responses of LDAPResult or responses
+ requests, servers will return responses containing the elements found
+ in LDAPResult to indicate the final status of the protocol operation
+ request.
+
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- containing the components of LDAPResult to indicate the final status
- of a protocol operation request.
-
LDAPResult ::= SEQUENCE {
resultCode ENUMERATED {
success (0),
compareFalse (5),
compareTrue (6),
authMethodNotSupported (7),
- strongAuthRequired (8),
+ strongerAuthRequired (8),
-- 9 reserved --
referral (10),
adminLimitExceeded (11),
... },
matchedDN LDAPDN,
diagnosticMessage LDAPString,
+ referral [3] Referral OPTIONAL }
+
+
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- referral [3] Referral OPTIONAL }
-
The resultCode enumeration is extensible as defined in Section 3.6 of
[LDAPIANA]. The meanings of the listed result codes are given in
Appendix A. If a server detects multiple errors for an operation,
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.
- If the server chooses not to return a textual diagnostic, the
- diagnosticMessage field MUST be empty.
+ Diagnostic messages typically supplement the resultCode with
+ additional information. 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
+ in finding the target (or base) object. This will be a truncated form
+ of the provided name or, if an alias was dereferenced while
+ attempting to locate the entry, of the resulting name. Otherwise the
+ matchedDN field is empty.
4.1.10. Referral
- The referral result code indicates that the contacted server does not
- hold the target entry of the request. The referral field is present
- in an LDAPResult if the resultCode field value is referral, and
- absent with all other result codes. It contains one or more
- references to one or more servers or services that may be accessed
- via LDAP or other protocols. Referrals can be returned in response to
- any operation request (except unbind and abandon which do not have
- responses). At least one URI MUST be present in the Referral.
+ The referral result code indicates that the contacted server cannot
+ or will not perform the operation and that one or more other servers
+ may be able to. Reasons for this include:
+
+ - The target entry of the request is not held locally, but the
+ server has knowledge of its possible existence elsewhere.
+
+ - The operation is restricted on this server -- perhaps due to a
+ read-only copy of an entry to be modified.
+
+ The referral field is present in an LDAPResult if the resultCode is
+ set to referral, and absent with all other result codes. It contains
+ one or more references to one or more servers or services that may be
+ accessed via LDAP or other protocols. Referrals can be returned in
+ response to any operation request (except Unbind and Abandon which do
+ not have responses). At least one URI MUST be present in the
+ Referral.
- During a search operation, after the baseObject is located, and
+ During a Search operation, after the baseObject is located, and
entries are being evaluated, the referral is not returned. Instead,
continuation references, described in Section 4.5.3, are returned
when other servers would need to be contacted to complete the
Referral ::= SEQUENCE SIZE (1..MAX) OF uri URI
- URI ::= LDAPString -- limited to characters permitted in
- -- URIs
-
- If the client wishes to progress the operation, it MUST follow the
- referral by contacting one of the supported services. If multiple
- URIs are present, the client assumes that any supported URI may be
- used to progress the operation.
-
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- Protocol peers that follow referrals MUST ensure that they do not
- loop between servers. They MUST NOT repeatedly contact the same
- 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
- of implementations MUST be able to handle at least ten nested
- referrals between the root and a leaf entry.
+ URI ::= LDAPString -- limited to characters permitted in
+ -- URIs
+
+ If the client wishes to progress the operation, it contacts one of
+ the supported services found in the referral. If multiple URIs are
+ present, the client assumes that any supported URI may be used to
+ progress the operation.
+
+ Clients that follow referrals MUST ensure that they do not loop
+ between servers. They MUST NOT repeatedly contact the same server for
+ the same request with the same parameters. Some clients use a counter
+ that is incremented each time referral handling occurs for an
+ operation, and these kinds of clients MUST be able to handle at least
+ ten nested referrals while progressing the operation.
A URI for a server implementing LDAP and accessible via [TCP]/[IP]
(v4 or v6) is written as an LDAP URL according to [LDAPURL].
- When an LDAP URL is used, the following instructions are followed:
+ Referral values which are LDAP URLs follow these rules:
+
+ - If an alias was dereferenced, the <dn> part of the LDAP URL MUST
+ be present, with the new target object name.
- - If an alias was dereferenced, the <dn> part of the URL MUST be
- present, with the new target object name. UTF-8 encoded characters
- appearing in the string representation of a DN or search filter
- may not be legal for URLs (e.g. spaces) and MUST be escaped using
- the % method in [URI].
- It is RECOMMENDED that the <dn> part be present to avoid
ambiguity.
- - If the <dn> part is present, the client MUST use this name in its
- next request to progress the operation, and if it is not present
- the client will use the same name as in the original request.
+
+ - If the <dn> part is present, the client uses this name in its next
+ request to progress the operation, and if it is not present the
+ client uses the same name as in the original request.
+
- Some servers (e.g. participating in distributed indexing) may
- provide a different filter in a URL of a referral for a search
+ provide a different filter in a URL of a referral for a Search
operation.
- - If the <filter> part of the LDAP URL is present, the client MUST
- use this filter in its next request to progress this search, and
- if it is not present the client MUST use the same filter as it
- used for that search.
- - For search, it is RECOMMENDED that the <scope> part be present to
+
+ - If the <filter> part of the LDAP URL is present, the client uses
+ this filter in its next request to progress this Search, and if it
+ is not present the client uses the same filter as it used for that
+ Search.
+
+ - For Search, it is RECOMMENDED that the <scope> part be present to
avoid ambiguity.
- - If the <scope> part is missing, the scope of the original search
+
+ - If the <scope> part is missing, the scope of the original Search
is used by the client to progress the operation.
+
- Other aspects of the new request may be the same as or different
from the request which generated the referral.
URIs is left to future specifications. Clients may ignore URIs that
they do not support.
+
+
+
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+
+ UTF-8 encoded characters appearing in the string representation of a
+ DN, search filter, or other fields of the referral value may not be
+ legal for URIs (e.g. spaces) and MUST be escaped using the % method
+ in [URI].
+
4.1.11. Controls
Controls sent by clients are termed 'request controls' and those sent
by servers are termed 'response controls'.
- When an extension calls for a particular response control to be sent
- in response to a request control, the response and request controls
- are termed to be "paired".
-
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Controls ::= SEQUENCE OF control Control
controlValue OCTET STRING OPTIONAL }
The controlType field is the dotted-decimal representation of an
- OBJECT IDENTIFIER which uniquely identifies the control, or the
- request control and its paired response control. This provides
- unambiguous naming of controls.
+ OBJECT IDENTIFIER which uniquely identifies the control. This
+ provides unambiguous naming of controls. Often, response control(s)
+ solicited by a request control share controlType values with the
+ request control.
The criticality field only has meaning in controls attached to
- request messages (except unbindRequest). For controls attached to
- response messages and the unbindRequest, the criticality field SHOULD
+ request messages (except UnbindRequest). For controls attached to
+ response messages and the UnbindRequest, the criticality field SHOULD
be FALSE, and MUST be ignored by the receiving protocol peer. A value
of TRUE indicates that it is unacceptable to perform the operation
- without applying the semantics of the control and FALSE otherwise.
- Specifically, the criticality field is applied as follows:
+ without applying the semantics of the control. Specifically, the
+ criticality field is applied as follows:
- Regardless of the value of the criticality field, if the server
recognizes the control type and it is appropriate for the
- If the server does not recognize the control type or it is not
appropriate for the operation, and the criticality field is TRUE,
the server MUST NOT perform the operation, and for operations that
- have a response message, MUST return unavailableCriticalExtension
- in the resultCode.
+ have a response message, MUST return with the resultCode set to
+ unavailableCriticalExtension.
- If the server does not recognize the control type or it is not
appropriate for the operation, and the criticality field is FALSE,
the server MUST ignore the control.
+
+
+
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+ Lightweight Directory Access Protocol Version 3
+
The controlValue may contain information associated with the
controlType. Its format is defined by the specification of the
control. Implementations MUST be prepared to handle arbitrary
of ASN.1, and BER encoded according to Section 5.1, it also follows
the extensibility rules in Section 4.
- Servers list the controlType of all request controls they recognize
- in the supportedControl attribute in the root DSE (Section 5.1 of
+ Servers list the controlType of request controls they recognize in
+ the 'supportedControl' attribute in the root DSE (Section 5.1 of
[Models]).
Controls SHOULD NOT be combined unless the semantics of the
combination has been specified. The semantics of control
combinations, if specified, are generally found in the control
- specification most recently published. In the absence of combination
- semantics, the behavior of the operation is undefined.
-
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-
- Additionally, unless order-dependent semantics are given in a
- specification, the order of a combination of controls in the SEQUENCE
- is ignored.
+ specification most recently published. When a combination of controls
+ is encountered whose semantics are invalid, not specified (or not
+ 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
+ considered not well-formed and the operation fails with
+ protocolError.
This document does not specify any controls. Controls may be
specified in other documents. Documents detailing control extensions
are defined above should not be altered by the control's
specification),
- - whether information is to be present in the controlValue field,
- and if so, the format of the controlValue contents,
+ - whether the controlValue field is present, and if so, the format
+ of its contents,
- the semantics of the control, and
4.2. Bind Operation
- The function of the Bind Operation is to allow authentication
+ The function of the Bind operation is to allow authentication
information to be exchanged between the client and server. The Bind
operation should be thought of as the "authenticate" operation.
- Authentication and security-related semantics of this operation are
- given in [AuthMeth].
+ Operational, authentication, and security-related semantics of this
+ operation are given in [AuthMeth].
- The Bind Request is defined as follows:
+
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+ Lightweight Directory Access Protocol Version 3
+
+ The Bind request is defined as follows:
BindRequest ::= [APPLICATION 0] SEQUENCE {
version INTEGER (1 .. 127),
mechanism LDAPString,
credentials OCTET STRING OPTIONAL }
- Fields of the Bind Request are:
+ Fields of the BindRequest are:
- version: A version number indicating the version of the protocol
- to be used in this LDAP association. This document describes
+ to be used at the LDAP message layer. This document describes
version 3 of the protocol. There is no version negotiation. The
-
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-
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). Server behavior is
- undefined when the name is a null value, simple authentication is
- used, and a non-null password is specified. Where the server
- attempts to locate the named object, it SHALL NOT perform alias
- dereferencing.
+ does not support the specified version, it MUST respond with a
+ BindResponse where the resultCode is set to protocolError.
+
+ - 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
- do not support a choice supplied by a client return
- authMethodNotSupported in the resultCode field of the
- BindResponse.
+ do not support a choice supplied by a client return a BindResponse
+ with the resultCode set to authMethodNotSupported.
Textual passwords (consisting of a character sequence with a known
character set and encoding) transferred to the server using the
octets) MUST NOT be altered. The determination of whether a
password is textual is a local client matter.
- Authorization is the use of this authentication information when
- performing operations. Authorization MAY be affected by factors
- outside of the LDAP Bind Request, such as those provided by lower
- layer security services.
-
+
+
+
+
+
+
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+ Lightweight Directory Access Protocol Version 3
+
4.2.1. Processing of the Bind Request
- Before processing a BindRequest, all outstanding operations MUST
+ Before processing a BindRequest, all uncompleted operations MUST
either complete or be abandoned. The server may either wait for the
- outstanding operations to complete, or abandon them. The server then
+ uncompleted operations to complete, or abandon them. The server then
proceeds to authenticate the client in either a single-step, or
- multi-step bind process. Each step requires the server to return a
+ multi-step Bind process. Each step requires the server to return a
BindResponse to indicate the status of authentication.
+ After sending a BindRequest, clients MUST NOT send further LDAP PDUs
+ until receiving the BindResponse. Similarly, servers SHOULD NOT
+ process or respond to requests received while processing a
+ BindRequest.
+
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
+ operationsError to that request, it may then send a BindRequest. If
this also fails or the client chooses not to bind on the existing
- connection, 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.
+ LDAP session, it may terminate the LDAP session, re-establish it and
+ begin again by first sending a PDU with a BindRequest. This will aid
+ in interoperating with servers implementing other versions of LDAP.
- Clients may send multiple Bind Requests on a connection to change the
- authentication and/or security associations or to complete a multi-
-
-
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-
- stage bind process. Authentication from earlier binds is subsequently
- ignored.
+ Clients may send multiple Bind requests to change the authentication
+ and/or security associations or to complete a multi-stage Bind
+ process. Authentication from earlier binds is subsequently ignored.
For some SASL authentication mechanisms, it may be necessary for the
- client to invoke the BindRequest multiple times. This is indicated by
- the server sending a BindResponse with the resultCode set to
- saslBindInProgress. This indicates that the server requires the
- client to send a new bind request, with the same sasl mechanism, to
- continue the authentication process. Clients MUST NOT invoke
- operations between two Bind Requests made as part of a multi-stage
- bind.
+ client to invoke the BindRequest multiple times ([AuthMeth] Section
+ 8.2). Clients MUST NOT invoke operations between two Bind requests
+ made as part of a multi-stage Bind.
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.
If the client sends a BindRequest with the sasl mechanism field as an
- empty string, the server MUST return a BindResponse with
- authMethodNotSupported as the resultCode. This will allow clients to
+ empty string, the server MUST return a BindResponse with the
+ resultCode set to authMethodNotSupported. This will allow clients to
abort a negotiation if it wishes to try again with the same SASL
mechanism.
- A failed Bind Operation has the effect of placing the connection in
- an anonymous state.
-
4.2.2. Bind Response
- The Bind Response is defined as follows.
+ The Bind response is defined as follows.
BindResponse ::= [APPLICATION 1] SEQUENCE {
COMPONENTS OF LDAPResult,
BindResponse consists simply of an indication from the server of the
status of the client's request for authentication.
- A successful bind operation is indicated by a BindResponse with a
+
+
+
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+ Lightweight Directory Access Protocol Version 3
+
+ A successful Bind operation is indicated by a BindResponse with a
resultCode set to success. Otherwise, an appropriate result code is
- set in the BindResponse. For bind, the protocolError result code may
- be used to indicate that the version number supplied by the client is
- unsupported.
+ set in the BindResponse. For BindResponse, the protocolError result
+ code may be used to indicate that the version number supplied by the
+ client is unsupported.
- If the client receives a BindResponse where the resultCode field is
+ If the client receives a BindResponse where the resultCode is set to
protocolError, it is to assume that the server does not support this
version of LDAP. While the client may be able proceed with another
- version of this protocol (this may or may not require establishing a
- new connection), how to proceed with another version of this protocol
- is beyond the scope of this document. Clients which are unable or
- unwilling to proceed SHOULD drop the underlying connection.
+ version of this protocol (this may or may not require closing and re-
+ establishing the transport connection), how to proceed with another
+ version of this protocol is beyond the scope of this document.
+ Clients which are unable or unwilling to proceed SHOULD terminate the
+ LDAP session.
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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-
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.
4.3. Unbind Operation
- The function of the Unbind Operation is to terminate an LDAP
- association and 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 session.
+ The Unbind operation is not the antithesis of the Bind operation as
+ the name implies. The naming of these operations are historical. The
+ Unbind operation should be thought of as the "quit" operation.
- The Unbind Operation is defined as follows:
+ The Unbind operation is defined as follows:
UnbindRequest ::= [APPLICATION 2] NULL
- 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. Outstanding operations are
- handled as specified in Section 5.2.
+ The client, upon transmission of the UnbindRequest, and the server,
+ upon receipt of the UnbindRequest are to gracefully terminate the
+ LDAP session as described in Section 5.3.
+
+ Uncompleted operations are handled as specified in Section 3.1.
4.4. Unsolicited Notification
An unsolicited notification is an LDAPMessage sent from the server to
the client which is not in response to any LDAPMessage received by
the server. It is used to signal an extraordinary condition in the
- server or in the connection between the client and the server. The
+ server or in the LDAP session between the client and the server. The
notification is of an advisory nature, and the server will not expect
any response to be returned from the client.
+
+
+
+
+
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+\f
+ Lightweight Directory Access Protocol Version 3
+
The unsolicited notification is structured as an LDAPMessage in which
- the messageID is zero and protocolOp is of the extendedResp form (See
- Section 4.12). The responseName field of the ExtendedResponse always
- contains an LDAPOID which is unique for this notification.
+ the messageID is zero and protocolOp is set to the extendedResp
+ choice using the ExtendedResponse type (See Section 4.12). The
+ responseName field of the ExtendedResponse always contains an LDAPOID
+ which is unique for this notification.
One unsolicited notification (Notice of Disconnection) is defined in
this document. The specification of an unsolicited notification
- the OBJECT IDENTIFIER assigned to the notification (to be
specified in the responseName,
- - the format of the contents (if any) of the responseValue,
+ - the format of the contents of the responseValue (if any),
- - the circumstances which will cause the notification to be
- returned, and
+ - the circumstances which will cause the notification to be sent,
+ and
- - the semantics of the operation.
+ - the semantics of the message.
4.4.1. Notice of Disconnection
-
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-
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
- failure. Note that this notification is not a response to an unbind
- requested by the client. Outstanding operations are handled as
- specified in Section 5.2.
+ the server is about to terminate the LDAP session on its own
+ initiative. This notification is intended to assist clients in
+ distinguishing between an exceptional server condition and a
+ transient network failure. Note that this notification is not a
+ response to an Unbind requested by the client. Uncompleted operations
+ are handled as specified in Section 3.1.
- The responseName is 1.3.6.1.4.1.1466.20036, the response field is
- absent, and the resultCode is used to indicate the reason for the
- disconnection.
+ The responseName is 1.3.6.1.4.1.1466.20036, the responseValue field
+ is absent, and the resultCode is used to indicate the reason for the
+ disconnection. When the strongerAuthRequired resultCode is returned
+ with this message, it indicates that the server has detected that an
+ established security association between the client and server has
+ unexpectedly failed or been compromised.
- 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 connections, 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
- messages to the client, and MUST close the connection.
+ Upon transmission of the Notice of Disconnection, the server
+ gracefully terminates the LDAP session as described in Section 5.3.
4.5. Search Operation
- The Search Operation is used to request a server to return, subject
+ The Search operation is used to request a server to return, subject
to access controls and other restrictions, a set of entries matching
a complex search criterion. This can be used to read attributes from
a single entry, from entries immediately subordinate to a particular
4.5.1. Search Request
- The Search Request is defined as follows:
+ The Search request is defined as follows:
+
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+ Lightweight Directory Access Protocol Version 3
+
SearchRequest ::= [APPLICATION 3] SEQUENCE {
baseObject LDAPDN,
scope ENUMERATED {
baseObject (0),
singleLevel (1),
- wholeSubtree (2) },
+ wholeSubtree (2),
+ ... },
derefAliases ENUMERATED {
-
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-
neverDerefAliases (0),
derefInSearching (1),
derefFindingBaseObj (2),
filter Filter,
attributes AttributeSelection }
- AttributeSelection ::= SEQUENCE OF selection LDAPString
- -- constrained to <attributeSelection> below
+ AttributeSelection ::= SEQUENCE OF selector LDAPString
+ -- The LDAPString is constrained to
+ -- <attributeSelector> in Section 4.5.1.7
Filter ::= CHOICE {
and [0] SET SIZE (1..MAX) OF filter Filter,
lessOrEqual [6] AttributeValueAssertion,
present [7] AttributeDescription,
approxMatch [8] AttributeValueAssertion,
- extensibleMatch [9] MatchingRuleAssertion }
+ 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,
+ initial [0] AssertionValue, -- can occur at most once
any [1] AssertionValue,
- final [2] AssertionValue } }
+ final [2] AssertionValue } -- can occur at most once
+ }
MatchingRuleAssertion ::= SEQUENCE {
matchingRule [1] MatchingRuleId OPTIONAL,
matchValue [3] AssertionValue,
dnAttributes [4] BOOLEAN DEFAULT FALSE }
- Fields of the Search Request are:
-
- - baseObject: The name of the base object entry relative to which
- the search is to be performed.
-
- - scope: Specifies the scope of the search to be performed. The
- semantics (as described in [X.511]) of the possible values of this
- field are:
-
- baseObject: The scope is constrained to the entry named by
- baseObject.
-
- singleLevel: The scope is constrained to the immediate
- subordinates of the entry named by baseObject.
-
+
+
+
+
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+\f
Lightweight Directory Access Protocol Version 3
- wholeSubtree: the scope is constrained to the entry named by
- the baseObject, and all its subordinates.
+ Note that an X.500 "list"-like operation can be emulated by the
+ client requesting a singleLevel Search operation with a filter
+ checking for the presence of the 'objectClass' attribute, and that an
+ X.500 "read"-like operation can be emulated by a baseObject Search
+ operation with the same filter. A server which provides a gateway to
+ X.500 is not required to use the Read or List operations, although it
+ may choose to do so, and if it does, it must provide the same
+ semantics as the X.500 Search operation.
+
+
+4.5.1.1 SearchRequest.baseObject
+ The name of the base object entry (or possibly the root) relative to
+ which the Search is to be performed.
- - derefAliases: An indicator as to how alias entries (as defined in
- [Models]) are to be handled in searching. The semantics of the
- possible values of this field are:
- neverDerefAliases: Do not dereference aliases in searching or
- in locating the base object of the search.
-
- derefInSearching: While searching, dereference any alias entry
- subordinate to the base object which is also in the search
- scope. The filter is applied to the dereferenced object(s). If
- the search scope is wholeSubtree, the search continues in the
- subtree of any dereferenced object. Aliases in that subtree are
- also dereferenced. Servers SHOULD eliminate duplicate entries
- that arise due to alias dereferencing while searching.
-
- derefFindingBaseObj: Dereference aliases in locating the base
- object of the search, but not when searching subordinates of
- the base object.
-
- derefAlways: Dereference aliases both in searching and in
- locating the base object of the search.
- Servers MUST detect looping while dereferencing aliases in order
- to prevent denial of service attacks of this nature.
-
- - sizeLimit: A size limit that restricts the maximum number of
- entries to be returned as a result of the search. A value of zero
- in this field indicates that no client-requested size limit
- restrictions are in effect for the search. Servers may also
- enforce a maximum number of entries to return.
-
- - timeLimit: A time limit that restricts the maximum time (in
- seconds) allowed for a search. A value of zero in this field
- indicates that no client-requested time limit restrictions are in
- effect for the search. Servers may also enforce a maximum time
- limit for the search.
-
- - typesOnly: An indicator as to whether search results are to
- contain both attribute descriptions and values, or just attribute
- descriptions. Setting this field to TRUE causes only attribute
- descriptions (no values) to be returned. Setting this field to
- FALSE causes both attribute descriptions and values to be
- returned.
-
- - filter: A filter that defines the conditions that must be
- fulfilled in order for the search to match a given entry.
+4.5.1.2 SearchRequest.scope
+
+ Specifies the scope of the Search to be performed. The semantics (as
+ described in [X.511]) of the defined values of this field are:
+
+ baseObject: The scope is constrained to the entry named by
+ baseObject.
+
+ singleLevel: The scope is constrained to the immediate
+ subordinates of the entry named by baseObject.
+
+ wholeSubtree: the scope is constrained to the entry named by the
+ baseObject, and all its subordinates.
+
+
+4.5.1.3 SearchRequest.derefAliases
+
+ An indicator as to whether or not alias entries (as defined in
+ [Models]) are to be dereferenced during stages of the Search
+ operation.
+
+ The act of dereferencing an alias includes recursively dereferencing
+ aliases which refer to aliases.
+
+ Servers MUST detect looping while dereferencing aliases in order to
+ prevent denial of service attacks of this nature.
+
+ The semantics of the defined values of this field are:
+
+ neverDerefAliases: Do not dereference aliases in searching or in
+ locating the base object of the Search.
- 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
- attribute values of entries in the scope of the search.
+
+
+
+
+
+
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+\f
Lightweight Directory Access Protocol Version 3
- (Implementor's note: the 'not' filter is an example of a tagged
- choice in an implicitly-tagged module. In BER this is treated as
- if the tag was explicit.)
-
- A server MUST evaluate filters according to the three-valued logic
- of X.511 (1993) Section 7.8.1. In summary, a filter is evaluated
- to either "TRUE", "FALSE" or "Undefined". If the filter evaluates
- to TRUE for a particular entry, then the attributes of that entry
- are returned as part of the search result (subject to any
- applicable access control restrictions). If the filter evaluates
- to FALSE or Undefined, then the entry is ignored for the search.
+ derefInSearching: While searching subordinates of the base object,
+ dereference any alias within the search scope. Dereferenced
+ objects become the vertices of further search scopes where the
+ Search operation is also applied. If the search scope is
+ wholeSubtree, the Search continues in the subtree(s) of any
+ dereferenced object. If the search scope is singleLevel, the
+ search is applied to any dereferenced objects, and is not applied
+ to their subordinates. Servers SHOULD eliminate duplicate entries
+ that arise due to alias dereferencing while searching.
- A filter of the "and" choice is TRUE if all the filters in the SET
- OF evaluate to TRUE, FALSE if at least one filter is FALSE, and
- otherwise Undefined. A filter of the "or" choice is FALSE if all
- of the filters in the SET OF evaluate to FALSE, TRUE if at least
- 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.
+ derefFindingBaseObj: Dereference aliases in locating the base
+ object of the Search, but not when searching subordinates of the
+ base object.
- The present match evaluates to TRUE where there is an attribute or
- subtype of the specified attribute description present in an
- entry, and FALSE otherwise (including a presence test with an
- unrecognized attribute description.)
-
- The matching rule for equalityMatch filter items is defined by the
- EQUALITY matching rule for the attribute type.
-
- There SHALL be at most one 'initial', and at most one 'final' in
- the 'substrings' of a SubstringFilter. If 'initial' is present, it
- SHALL be the first element of 'substrings'. If 'final' is present,
- it SHALL be the last element of 'substrings'.
- The matching rule for AssertionValues in a substrings filter item
- is defined by the SUBSTR matching rule for the attribute type.
- Note that the AssertionValue in a substrings filter item conforms
- to the assertion syntax of the EQUALITY matching rule for the
- attribute type rather than the assertion syntax of the SUBSTR
- matching rule for the attribute type. Conceptually, the entire
- SubstringFilter is converted into an assertion value of the
- substrings matching rule prior to applying the rule.
-
- The matching rule for the greaterOrEqual filter item is defined by
- the ORDERING and EQUALITY matching rules for the attribute type.
-
- The matching rule for the lessOrEqual filter item is defined by
- the ORDERING matching rule for the attribute type.
-
- An approxMatch filter item evaluates to TRUE when there is a value
- of the attribute or subtype for which some locally-defined
- approximate matching algorithm (e.g. spelling variations, phonetic
- match, etc.) returns TRUE. If an item matches for equality, it
- also satisfies an approximate match. If approximate matching is
- not supported, this filter item should be treated as an
- equalityMatch.
-
-Sermersheim Internet-Draft - Expires Aug 2004 Page 20 \f
+ derefAlways: Dereference aliases both in searching and in locating
+ the base object of the Search.
+
+
+4.5.1.4 SearchRequest.sizeLimit
+
+ A size limit that restricts the maximum number of entries to be
+ returned as a result of the Search. A value of zero in this field
+ indicates that no client-requested size limit restrictions are in
+ effect for the Search. Servers may also enforce a maximum number of
+ entries to return.
+
+
+4.5.1.5 SearchRequest.timeLimit
+
+ A time limit that restricts the maximum time (in seconds) allowed for
+ a Search. A value of zero in this field indicates that no client-
+ requested time limit restrictions are in effect for the Search.
+ Servers may also enforce a maximum time limit for the Search.
+
+
+4.5.1.6 SearchRequest.typesOnly
+
+ An indicator as to whether Search results are to contain both
+ attribute descriptions and values, or just attribute descriptions.
+ Setting this field to TRUE causes only attribute descriptions (no
+ values) to be returned. Setting this field to FALSE causes both
+ attribute descriptions and values to be returned.
+
+
+
+
+
+
+
+
+
+
+
+
+
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+\f
Lightweight Directory Access Protocol Version 3
-
- An extensibleMatch filter item is evaluated as follows:
+4.5.1.7 SearchRequest.filter
+
+ A filter that defines the conditions that must be fulfilled in order
+ for the Search to match a given entry.
+
+ 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 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 if the tag was explicit.)
+
+ A server MUST evaluate filters according to the three-valued logic of
+ [X.511] (1993) Clause 7.8.1. In summary, a filter is evaluated to
+ either "TRUE", "FALSE" or "Undefined". If the filter evaluates to
+ TRUE for a particular entry, then the attributes of that entry are
+ returned as part of the Search result (subject to any applicable
+ access control restrictions). If the filter evaluates to FALSE or
+ Undefined, then the entry is ignored for the Search.
+
+ A filter of the "and" choice is TRUE if all the filters in the SET OF
+ evaluate to TRUE, FALSE if at least one filter is FALSE, and
+ otherwise Undefined. A filter of the "or" choice is FALSE if all of
+ the filters in the SET OF evaluate to FALSE, TRUE if at least 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.
+
+ A filter item evaluates to Undefined when the server would not be
+ 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.
- If the matchingRule field is absent, the type field MUST be
- present, and an equality match is performed for that type.
-
- If the type field is absent and the matchingRule is present, the
- matchValue is compared against all attributes in an entry which
- support that matchingRule. The matchingRule determines the
- syntax for the assertion value. The filter item evaluates to
- TRUE if it matches with at least one attribute in the entry,
- FALSE if it does not match any attribute in the entry, and
- Undefined if the matchingRule is not recognized or the
- assertionValue is invalid.
-
- 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
- suitable for use with the specified type (see [Syntaxes]),
- otherwise the filter item is Undefined.
-
- If the dnAttributes field is set to TRUE, the match is
- additionally applied against all the AttributeValueAssertions in
- an entry's distinguished name, and evaluates to TRUE if there is
- at least one attribute in the distinguished name for which the
- filter item evaluates to TRUE. The dnAttributes field is present
- to alleviate the need for multiple versions of generic matching
- rules (such as word matching), where one applies to entries and
- 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 matching rule id 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.
-
- Servers MUST NOT return errors if attribute descriptions or
- matching rule ids are not recognized, assertion values are
- invalid, or the assertion syntax is not supported. More details of
- filter processing are given in Section 7.8 of [X.511].
+ - 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.
- - attributes: A list of the attributes to be returned from each
- entry which matches the search filter. LDAPString values of this
- field are constrained to the following Augmented Backus-Naur Form
- ([ABNF]):
+ - The type of filtering requested is not implemented.
- attributeSelection = attributedescription / selectionspecial
+ - The assertion value is invalid.
+
+
+
+
+
+
+
+
+
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+\f
Lightweight Directory Access Protocol Version 3
+ 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.
- selectionspecial = noattrs / alluserattrs
+ Servers MUST NOT return errors if attribute descriptions or matching
+ rule ids are not recognized, assertion values are invalid, or the
+ assertion syntax is not supported. More details of filter processing
+ are given in Clause 7.8 of [X.511].
+
+
+4.5.1.7.1 SearchRequest.filter.equalityMatch
- noattrs = %x31.2E.31 ; "1.1"
+ The matching rule for equalityMatch filter items is defined by the
+ EQUALITY matching rule for the attribute type.
- alluserattrs = %x2A ; asterisk ("*")
- The <attributedescription> production is defined in Section 2.5 of
- [Models].
+4.5.1.7.2 SearchRequest.filter.substrings
- There are three special cases which may exist in the attribute
- selection:
- - an empty list with no attributes,
- - a list containing "*" (with zero or more attribute
- descriptions), and
- - a list containing only "1.1".
+ There SHALL be at most one 'initial', and at most one 'final' in the
+ 'substrings' of a SubstringFilter. If 'initial' is present, it SHALL
+ be the first element of 'substrings'. If 'final' is present, it SHALL
+ be the last element of 'substrings'.
- An empty list requests the return of all user attributes.
+ The matching rule for an AssertionValue in a substrings filter item
+ is defined by the SUBSTR matching rule for the attribute type. Note
+ that the AssertionValue in a substrings filter item conforms to the
+ assertion syntax of the EQUALITY matching rule for the attribute type
+ rather than the assertion syntax of the SUBSTR matching rule for the
+ attribute type. Conceptually, the entire SubstringFilter is converted
+ into an assertion value of the substrings matching rule prior to
+ applying the rule.
- A list containing "*" requests all user attributes in addition to
- other listed (operational) attributes.
- A list containing only the OID "1.1" indicates that no values are
- to be returned. If "1.1" is provided with other values, the "1.1"
- value is ignored. This OID was chosen because it does not (and can
- not) correspond to any attribute in use.
-
- Client implementors should note that even if all user attributes
- are requested, some attributes and/or attribute values of the
- entry may not be included in search results due to access controls
- or other restrictions. Furthermore, servers will not return
- operational attributes, such as objectClasses or attributeTypes,
- unless they are listed by name. Operational attributes are
- described in [Models].
-
- Attributes are returned at most once in an entry. If an attribute
- description is named more than once in the list, the subsequent
- names are ignored. If an attribute description in the list is not
- recognized, it is ignored by the server.
+4.5.1.7.3 SearchRequest.filter.greaterOrEqual
+
+ The matching rule for the greaterOrEqual filter item is defined by
+ the ORDERING and EQUALITY matching rules for the attribute type.
+
+
+4.5.1.7.4 SearchRequest.filter.lessOrEqual
+
+ The matching rule for the lessOrEqual filter item is defined by the
+ ORDERING matching rule for the attribute type.
+
+
+4.5.1.7.5 SearchRequest.filter.present
+
+ The present match evaluates to TRUE where there is an attribute or
+ subtype of the specified attribute description present in an entry,
+ and FALSE otherwise (including a presence test with an unrecognized
+ attribute description).
+
+
+
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+\f
+ Lightweight Directory Access Protocol Version 3
+
+4.5.1.7.6 SearchRequest.filter.approxMatch
+
+ An approxMatch filter item evaluates to TRUE when there is a value of
+ the attribute or subtype for which some locally-defined approximate
+ matching algorithm (e.g. spelling variations, phonetic 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 treated as an equalityMatch.
+
+
+4.5.1.7.7 SearchRequest.filter.extensibleMatch
+
+ The fields of the extensibleMatch filter item are evaluated as
+ follows:
+
+ - If the matchingRule field is absent, the type field MUST be
+ present, and an equality match is performed for that type.
- Note that an X.500 "list"-like operation can be emulated by the
- client requesting a one-level LDAP search operation with a filter
- checking for the presence of the 'objectClass' attribute, and that an
- X.500 "read"-like operation can be emulated by a base object LDAP
- search operation with the same filter. A server which provides a
- gateway to X.500 is not required to use the Read or List operations,
- although it may choose to do so, and if it does, it must provide the
- same semantics as the X.500 search operation.
+ - If the type field is absent and the matchingRule is present, the
+ matchValue is compared against all attributes in an entry which
+ support that matchingRule.
+
+ - If the type field is present and the matchingRule is present, the
+ matchValue is compared against entry attributes of the specified
+ type.
+
+ - If the dnAttributes field is set to TRUE, the match is
+ additionally applied against all the AttributeValueAssertions in
+ an entry's distinguished name, and evaluates to TRUE if there is
+ at least one attribute in the distinguished name for which the
+ filter item evaluates to TRUE. The dnAttributes field is present
+ to alleviate the need for multiple versions of generic matching
+ rules (such as word matching), where one applies to entries and
+ another applies to entries and DN attributes as well.
+
+ The matchingRule used for evaluation determines the syntax for the
+ assertion value. Once the matchingRule and attribute(s) have been
+ determined, the filter item evaluates to TRUE if it matches with at
+ least one attribute in the entry, FALSE if it does not match any
+ attribute in the entry, and Undefined if the matchingRule is not
+ recognized, the matchingRule is unsuitable for use with the specified
+ type, or the assertionValue is invalid.
-4.5.2. Search Result
+4.5.1.7 SearchRequest.attributes
+
+ A selection list of the attributes to be returned from each entry
+ which matches the search filter. LDAPString values of this field are
+ constrained to the following Augmented Backus-Naur Form ([ABNF]):
+
+ attributeSelector = attributedescription / selectorspecial
+
+ selectorspecial = noattrs / alluserattrs
-
-
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+\f
Lightweight Directory Access Protocol Version 3
- The results of the search operation are returned as zero or more
- searchResultEntry messages, zero or more SearchResultReference
- messages, followed by a single searchResultDone message.
+ noattrs = %x31.2E.31 ; "1.1"
+
+ alluserattrs = %x2A ; asterisk ("*")
+
+ The <attributedescription> production is defined in Section 2.5 of
+ [Models].
+
+ There are three special cases which may appear in the attributes
+ selection list:
+
+ - an empty list with no attributes,
+
+ - a list containing "*" (with zero or more attribute
+ descriptions), and
+
+ - a list containing only "1.1".
+
+ An empty list requests the return of all user attributes.
+
+ A list containing "*" requests the return of all user attributes
+ in addition to other listed (operational) attributes.
+
+ A list containing only the OID "1.1" indicates that no attributes
+ are to be returned. If "1.1" is provided with other
+ attributeSelector values, the "1.1" attributeSelector is ignored.
+ This OID was chosen because it does not (and can not) correspond
+ to any attribute in use.
+
+ Client implementors should note that even if all user attributes are
+ requested, some attributes and/or attribute values of the entry may
+ not be included in Search results due to access controls or other
+ restrictions. Furthermore, servers will not return operational
+ attributes, such as objectClasses or attributeTypes, unless they are
+ listed by name. Operational attributes are described in [Models].
+
+ Attributes are returned at most once in an entry. If an attribute
+ description is named more than once in the list, the subsequent names
+ are ignored. If an attribute description in the list is not
+ recognized, it is ignored by the server.
+
+
+4.5.2. Search Result
+
+ The results of the Search operation are returned as zero or more
+ SearchResultEntry and/or SearchResultReference messages, followed by
+ a single SearchResultDone message.
SearchResultEntry ::= [APPLICATION 4] SEQUENCE {
objectName LDAPDN,
PartialAttributeList ::= SEQUENCE OF
partialAttribute PartialAttribute
- -- Note that the PartialAttributeList may hold zero elements.
- -- This may happen when none of the attributes of an entry
- -- were requested, or could be returned.
- -- Note also that the partialAttribute vals set may hold zero
- -- elements. This may happen when typesOnly is requested, access
- -- controls prevent the return of values, or other reasons.
+
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+\f
+ Lightweight Directory Access Protocol Version 3
+
SearchResultReference ::= [APPLICATION 19] SEQUENCE
SIZE (1..MAX) OF uri URI
SearchResultDone ::= [APPLICATION 5] LDAPResult
- Each SearchResultEntry represents an entry found during the search.
+ Each SearchResultEntry represents an entry found during the Search.
Each SearchResultReference represents an area not yet explored during
- the search. The SearchResultEntry and SearchResultReference PDUs may
+ the Search. The SearchResultEntry and SearchResultReference PDUs may
come in any order. Following all the SearchResultReference and
SearchResultEntry responses, the server returns a SearchResultDone
response, which contains an indication of success, or detailing any
Each entry returned in a SearchResultEntry will contain all
appropriate attributes as specified in the attributes field of the
- Search Request. Return of attributes is subject to access control and
- other administrative policy.
+ Search Request, subject to access control and other administrative
+ policy. Note that the PartialAttributeList may hold zero elements.
+ This may happen when none of the attributes of an entry were
+ requested, or could be returned. Note also that the partialAttribute
+ vals set may hold zero elements. This may happen when typesOnly is
+ requested, access controls prevent the return of values, or other
+ reasons.
Some attributes may be constructed by the server and appear in a
SearchResultEntry attribute list, although they are not stored
4.5.3. Continuation References in the Search Result
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
+ baseObject but was unable or unwilling to search one or more non-
+ local entries, the server may return one or more
+ SearchResultReference messages, each containing a reference to
+ another set of servers for continuing the operation. A server MUST
+ NOT return any SearchResultReference messages 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 referral or
+ noSuchObject result code (depending on the server's knowledge of the
+ entry named in the baseObject).
+
+
+
+
+
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+\f
Lightweight Directory Access Protocol Version 3
- containing a reference to another set of servers for continuing the
- 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 a referral
- result code.
-
If a server holds a copy or partial copy of the subordinate naming
- context [Section 5 of Models], it may use the search filter to
+ context (Section 5 of [Models]), it may use the search filter to
determine whether or not to return a SearchResultReference response.
Otherwise SearchResultReference responses are always returned when in
scope.
The SearchResultReference is of the same data type as the Referral.
+ If the client wishes to progress the Search, it issues a new Search
+ operation for each SearchResultReference that is returned. If
+ multiple URIs are present, the client assumes that any supported URI
+ may be used to progress the operation.
+
+ Clients that follow search continuation references MUST ensure that
+ they do not loop between servers. They MUST NOT repeatedly contact
+ the same server for the same request with the same parameters. Some
+ clients use a counter that is incremented each time search result
+ reference handling occurs for an operation, and these kinds of
+ clients MUST be able to handle at least ten nested referrals while
+ progressing the operation.
+
+ Note that the Abandon operation described in Section 4.11 applies
+ only to a particular operation sent at the LDAP message layer between
+ a client and server. The client must abandon subsequent Search
+ operations it wishes to individually.
+
A URI for a server implementing LDAP and accessible via [TCP]/[IP]
(v4 or v6) is written as an LDAP URL according to [LDAPURL].
- 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
- server. The client must abandon subsequent search operations it
- wishes to individually.
+ SearchResultReference values which are LDAP URLs follow these rules:
+
+ - The <dn> part of the LDAP URL MUST be present, with the new target
+ object name. The client uses this name when following the
+ reference.
- Clients that follow search continuation references MUST ensure that
- they do not loop between servers. They MUST NOT repeatedly contact
- the same server for the same request with the same target entry name,
- scope and filter. Some clients use a counter that is incremented each
- time search result reference handling occurs for an operation, and
- these kinds of clients MUST be able to handle at least ten nested
- search result references between the root and a leaf entry.
-
- When an LDAP URL is used, the following instructions are followed:
-
- - The <dn> part of the URL MUST be present, with the new target
- object name. The client MUST use this name when following the
- reference. UTF-8 encoded characters appearing in the string
- representation of a DN or search filter may not be legal for URLs
- (e.g. spaces) and MUST be escaped using the % method in [URI].
- Some servers (e.g. participating in distributed indexing) may
- provide a different filter in a URL of a SearchResultReference.
- - If the <filter> part of the URL is present, the client MUST use
- this filter in its next request to progress this search, and if it
- is not present the client MUST use the same filter as it used for
- that search.
+ provide a different filter in the LDAP URL.
+
+ - If the <filter> part of the LDAP URL is present, the client uses
+ this filter in its next request to progress this Search, and if it
+ is not present the client uses the same filter as it used for that
+ Search.
+
- If the originating search scope was singleLevel, the <scope> part
- of the URL will be "base".
- - 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
+ of the LDAP URL will be "base".
+
+ - It is RECOMMENDED that the <scope> part be present to avoid
+ ambiguity. In the absence of a <scope> part, the scope of the
+ original Search request is assumed.
+
+ - Other aspects of the new Search request may be the same as or
+ different from the Search request which generated the
SearchResultReference.
- - The name of an unexplored subtree in a SearchResultReference need
- not be subordinate to the base object.
+
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+\f
Lightweight Directory Access Protocol Version 3
+ - The name of an unexplored subtree in a SearchResultReference need
+ not be subordinate to the base object.
Other kinds of URIs may be returned. The syntax and semantics of such
URIs is left to future specifications. Clients may ignore URIs that
they do not support.
+
+ UTF-8 encoded characters appearing in the string representation of a
+ DN, search filter, or other fields of the referral value may not be
+ legal for URIs (e.g. spaces) and MUST be escaped using the % method
+ in [URI].
+
4.5.3.1. Examples
For example, suppose the contacted server (hosta) holds the entry
<DC=Example,DC=NET> and the entry <CN=Manager,DC=Example,DC=NET>. It
- knows that either LDAP-capable servers (hostb) or (hostc) hold
+ knows that both LDAP servers (hostb) and (hostc) hold
<OU=People,DC=Example,DC=NET> (one is the master and the other server
a shadow), and that LDAP-capable server (hostd) holds the subtree
- <OU=Roles,DC=Example,DC=NET>. If a wholeSubtree search of
+ <OU=Roles,DC=Example,DC=NET>. If a wholeSubtree Search of
<DC=Example,DC=NET> is requested to the contacted server, it may
return the following:
Client implementors should note that when following a
SearchResultReference, additional SearchResultReference may be
generated. Continuing the example, if the client contacted the server
- (hostb) and issued the search for the subtree
+ (hostb) and issued the Search request for the subtree
<OU=People,DC=Example,DC=NET>, the server might respond as follows:
SearchResultEntry for OU=People,DC=Example,DC=NET
ldap://hostf/OU=Consultants,OU=People,DC=Example,DC=NET??sub }
SearchResultDone (success)
- Similarly, if a singleLevel search of <DC=Example,DC=NET> is
+ Similarly, if a singleLevel Search of <DC=Example,DC=NET> is
requested to the contacted server, it may return the following:
+
+
+
+
+
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+\f
+ Lightweight Directory Access Protocol Version 3
+
SearchResultEntry for CN=Manager,DC=Example,DC=NET
SearchResultReference {
ldap://hostb/OU=People,DC=Example,DC=NET??base
ldap://hostd/OU=Roles,DC=Example,DC=NET??base }
SearchResultDone (success)
- If the contacted server does not hold the base object for the search,
- then it will return a referral to the client. For example, if the
- client requests a subtree search of <DC=Example,DC=ORG> to hosta, the
- server may return only a SearchResultDone containing a referral.
-
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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
+ subtree Search of <DC=Example,DC=ORG> to hosta, the server returns a
+ SearchResultDone containing a referral.
SearchResultDone (referral) {
ldap://hostg/DC=Example,DC=ORG??sub }
4.6. Modify Operation
- The Modify Operation allows a client to request that a modification
+ The Modify operation allows a client to request that a modification
of an entry be performed on its behalf by a server. The Modify
Request is defined as follows:
operation ENUMERATED {
add (0),
delete (1),
- replace (2) },
+ replace (2),
+ ... },
modification PartialAttribute } }
Fields of the Modify Request are:
- - object: The name of the object to be modified. The value of this
- field contains the DN of the entry to be modified. The server
- SHALL NOT perform any alias dereferencing in determining the
- object to be modified.
+ - object: The value of this field contains the name of the entry to
+ be modified. The server SHALL NOT perform any alias dereferencing
+ in determining the object to be modified.
- changes: A list of modifications to be performed on the entry. The
entire list of modifications MUST be performed in the order they
modifications may violate certain aspects of the directory schema
(such as the object class definition and DIT content rule), the
resulting entry after the entire list of modifications is
- performed MUST conform to the requirements of the directory schema
- [Models].
+ performed MUST conform to the requirements of the directory model
+ and controlling schema [Models].
- operation: Used to specify the type of modification being
performed. Each operation type acts on the following
- modification. The values of this field have the following
+ modification. The values of this field have the following
semantics respectively:
+
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+\f
+ Lightweight Directory Access Protocol Version 3
+
add: add values listed to the modification attribute,
creating the attribute if necessary;
- 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;
+ delete: delete values listed from the modification attribute.
+ If no values are listed, or if all current values of the
+ attribute are listed, the entire attribute is removed;
replace: replace all existing values of the modification
attribute with the new values listed, creating the attribute
delete the entire attribute if it exists, and is ignored if
the attribute does not exist.
-
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- Lightweight Directory Access Protocol Version 3
-
- modification: A PartialAttribute (which may have an empty SET
of vals) used to hold the attribute type or attribute type and
values being modified.
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.
-
- 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
- relative distinguished name. An attempt to do so will result in the
- server returning the notAllowedOnRDN result code. The Modify DN
- Operation described in Section 4.9 is used to rename an entry.
+ operation. Whether the modification was applied or not cannot be
+ determined by the client if the Modify Response was not received
+ (e.g. the LDAP session was terminated or the Modify operation was
+ abandoned).
+
+ Servers MUST ensure that entries conform to user and system schema
+ rules or other data model constraints. 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 relative distinguished name. An
+ attempt to do so will result in the server returning the
+ notAllowedOnRDN result code. The Modify DN operation described in
+ Section 4.9 is used to rename an entry.
+
+ For attribute types which specify no equality matching, the rules in
+ Section 2.5.1 of [Models] are followed.
Note that due to the simplifications made in LDAP, there is not a
direct mapping of the changes in an LDAP ModifyRequest onto the
change. If successful, the final effect of the operations on the
entry MUST be identical.
+
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+\f
+ Lightweight Directory Access Protocol Version 3
+
4.7. Add Operation
- The Add Operation allows a client to request the addition of an entry
+ The Add operation allows a client to request the addition of an entry
into the Directory. The Add Request is defined as follows:
AddRequest ::= [APPLICATION 8] SEQUENCE {
dereference any aliases in locating the entry to be added.
- attributes: the list of attributes that, along with those from the
- RDN, make up the content of the entry being added. Clients MUST
- include the 'objectClass' attribute, and values of any mandatory
-
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- Lightweight Directory Access Protocol Version 3
-
- attributes of the listed object classes. Clients MUST NOT supply
- NO-USER-MODIFICATION attributes such as the createTimestamp or
- creatorsName attributes, since the server maintains these
- automatically.
+ RDN, make up the content of the entry being added. Clients MAY or
+ MAY NOT include the RDN attribute(s) in this list. Clients MUST
+ NOT supply NO-USER-MODIFICATION attributes such as the
+ createTimestamp or creatorsName attributes, since the server
+ maintains these automatically.
+
+ Servers MUST ensure that entries conform to user and system schema
+ rules or other data model constraints. For attribute types which
+ specify no equality matching, the rules in Section 2.5.1 of [Models]
+ are followed (this applies to the naming attribute in addition to any
+ multi-valued attributes being added).
The entry named in the entry field of the AddRequest MUST NOT exist
for the AddRequest to succeed. The immediate superior (parent) of an
exist, then the server would return the noSuchObject result code with
the matchedDN field containing <DC=NET>.
- If the entry to be added would not fall within a naming context
- [Section 5 of Models] held by the server, and the server has
- knowledge of where that entry is to be located, a referral to the
- server(s) holding the parent entry should be returned.
-
- Server implementations SHOULD NOT restrict where entries can be
- located in the Directory unless DIT structure rules are in place.
- Some servers allow the administrator to restrict the classes of
- entries which can be added to the Directory.
-
Upon receipt of an Add Request, a server will attempt to add the
- requested entry. The result of the add attempt will be returned to
+ requested entry. The result of the Add attempt will be returned to
the client in the Add Response, defined as follows:
AddResponse ::= [APPLICATION 9] LDAPResult
4.8. Delete Operation
- The Delete Operation allows a client to request the removal of an
+ The Delete operation allows a client to request the removal of an
entry from the Directory. The Delete Request is defined as follows:
DelRequest ::= [APPLICATION 10] LDAPDN
+
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+\f
+ Lightweight Directory Access Protocol Version 3
+
The Delete Request consists of the name of the entry to be deleted.
The server SHALL NOT dereference aliases while resolving the name of
DelResponse ::= [APPLICATION 11] LDAPResult
-
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- Lightweight Directory Access Protocol Version 3
-
4.9. Modify DN Operation
- The Modify DN Operation allows a client to change the Relative
+ The Modify DN operation allows a client to change the Relative
Distinguished Name (RDN) of an entry in the Directory, and/or to move
a subtree of entries to a new location in the Directory. The Modify
DN Request is defined as follows:
- entry: the name of the entry to be changed. This entry may or may
not have subordinate entries.
- - newrdn: the new RDN of the entry. If an attribute value in the
- newrdn does not already exist in the entry (either as part of the
- old RDN or as a non-distinguished value), it is added. If it
- cannot be added, an appropriate error is returned.
-
+ - newrdn: the new RDN of the entry. The value of the old RDN is
+ supplied when moving the entry to a new superior without changing
+ its RDN. Attribute values of the new RDN not matching any
+ attribute value of the entry are added to the entry and an
+ appropriate error is returned if this fails.
+
- deleteoldrdn: a boolean field that controls whether the old RDN
attribute values are to be retained as attributes of the entry, or
deleted from the entry.
the name change and return the result in the Modify DN Response,
defined as follows:
+
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+ Lightweight Directory Access Protocol Version 3
+
ModifyDNResponse ::= [APPLICATION 13] LDAPResult
For example, if the entry named in the entry field was <cn=John
already an entry with that name, the operation would fail with the
entryAlreadyExists result code.
+ Servers MUST ensure that entries conform to user and system schema
+ rules or other data model constraints. For attribute types which
+ specify no equality matching, the rules in Section 2.5.1 of [Models]
+ are followed (this pertains to newrdn and deleteoldrdn).
+
The object named in newSuperior MUST exist. For example, if the
client attempted to add <CN=JS,DC=Example,DC=NET>, the
<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>.
-
-
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-
If the deleteoldrdn field is TRUE, the attribute values forming the
old RDN but not the new RDN are deleted from the entry. If the
deleteoldrdn field is FALSE, the attribute values forming the old RDN
- will be retained as non-distinguished attribute values of the entry.
- The server MUST fail the operation and return an error in the result
- code if the setting of the deleteoldrdn field would cause a schema
- inconsistency in the entry.
+ will be retained as non-distinguished attribute values of the entry.
Note that X.500 restricts the ModifyDN operation to only affect
entries that are contained within a single server. If the LDAP server
4.10. Compare Operation
- The Compare Operation allows a client to compare an assertion value
+ The Compare operation allows a client to compare an assertion value
with the values of a particular attribute in a particular entry in
the Directory. The Compare Request is defined as follows:
- entry: the name of the entry to be compared. The server SHALL NOT
dereference any aliases in locating the entry to be compared.
- - ava: holds the attribute description and assertion value with
- which an attribute in the entry is to be compared.
+ - ava: holds the attribute value assertion to be compared.
Upon receipt of a Compare Request, a server will attempt to perform
the requested comparison and return the result in the Compare
Response, defined as follows:
+
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+ Lightweight Directory Access Protocol Version 3
+
CompareResponse ::= [APPLICATION 15] LDAPResult
- The resultCode field is set to compareTrue, compareFalse, or an
- appropriate error. compareTrue indicates that the assertion value in
- the ava field is equivalent to a value of the attribute or subtype
- (according to the attribute's EQUALITY matching rule). compareFalse
- indicates that the comparison of the assertion value in the ava field
- and the values of the attribute or subtype resulted in an Undefined
- (Section 4.5.1) or non-equivalent match.
-
- In the event that the attribute or subtype is not present in the
- entry, the resultCode field is set to noSuchAttribute. If the
- attribute is unknown, the resultCode is set to
- undefinedAttributeType. If the attribute or subtype has no equality
- matching rule, innapropriateMatching is returned in the resultCode.
-
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-
-
+ The resultCode is set to compareTrue, compareFalse, or an appropriate
+ error. compareTrue indicates that the assertion value in 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 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.
+
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.
4.11. Abandon Operation
- The function of the Abandon Operation is to allow a client to request
- that the server abandon an outstanding operation. The Abandon Request
+ The function of the Abandon operation is to allow a client to request
+ that the server abandon an uncompleted operation. The Abandon Request
is defined as follows:
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 message
- id. This is distinct from the id of the earlier operation being
- abandoned.
+ The MessageID is that of an operation which was requested earlier at
+ this LDAP message layer. 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
- by the MessageID. Operation responses are not sent for successfully
- abandoned operations, thus the application of the Abandon operation
- is limited to uses where the client does not require an indication of
- its outcome.
+ by the MessageID. Since the client cannot tell the difference between
+ a successfully abandoned operation and an uncompleted operation, the
+ application of the Abandon operation is limited to uses where the
+ client does not require an indication of its outcome.
- Abandon, Bind, Unbind, and StartTLS operations cannot be abandoned.
- The ability to abandon other (particularly update) operations is at
- the discretion of the server.
+ Abandon, Bind, Unbind, and StartTLS operations cannot be abandoned.
In the event that a server receives an Abandon Request on a Search
- Operation in the midst of transmitting responses to the search, that
+ operation in the midst of transmitting responses to the Search, that
server MUST cease transmitting entry responses to the abandoned
- request immediately, and MUST NOT send the SearchResponseDone. Of
+ request immediately, and MUST NOT send the SearchResultDone. Of
course, the server MUST ensure that only properly encoded LDAPMessage
PDUs are transmitted.
- Clients should not send abandon requests for the same operation
+ The ability to abandon other (particularly update) operations is at
+ the discretion of the server.
+
+ Clients should not send Abandon requests for the same operation
multiple times, and MUST also be prepared to receive results from
operations it has abandoned (since these may have been in transit
- when the abandon was requested, or are not able to be abandoned).
+ when the Abandon was requested, or are not able to be abandoned).
- Servers MUST discard abandon requests for message IDs they do not
+
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+ Lightweight Directory Access Protocol Version 3
+
+ Servers MUST discard Abandon requests for message IDs they do not
recognize, for operations which cannot be abandoned, and for
operations which have already been abandoned.
4.12. Extended Operation
- The extended operation allows additional operations to be defined for
- services not already available in the protocol. For example, to add
+ 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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-
- The extended operation allows clients to make requests and receive
+ 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.
- Each extended operation consists of an extended request and an
- extended response.
+ Each Extended operation consists of an Extended request and an
+ Extended response.
ExtendedRequest ::= [APPLICATION 23] SEQUENCE {
requestName [0] LDAPOID,
responseValue) is implicitly known and associated with the request by
the messageID.
- If the requestName is not recognized by the server, the server MUST
- NOT provide a responseName nor a responseValue and MUST return a
- resultCode of protocolError.
+ If the Extended operation associated with the requestName is not
+ supported by the server, the server MUST NOT provide a responseName
+ nor a responseValue and MUST return with resultCode set to
+ protocolError.
The requestValue and responseValue fields contain any information
associated with the operation. The format of these fields is defined
- by the specification of the extended operation. Implementations MUST
+ by the specification of the Extended operation. Implementations MUST
be prepared to handle arbitrary contents of these fields, including
zero bytes. Values that are defined in terms of ASN.1 and BER encoded
according to Section 5.1, also follow the extensibility rules in
Section 4.
- It is RECOMMENDED that servers list the requestName of extended
- operations they support in the 'supportedExtension' attribute of the
- root DSE [Models].
-
+
+
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+ Lightweight Directory Access Protocol Version 3
+
+ Servers list the requestName of Extended Requests they recognize in
+ the 'supportedExtension' attribute in the root DSE (Section 5.1 of
+ [Models]).
+
Extended operations may be specified in other documents. The
- specification of an extended operation consists of:
+ specification of an Extended operation consists of:
+
+ - the OBJECT IDENTIFIER assigned to the requestName,
- - the OBJECT IDENTIFIER assigned to the requestName (and possibly
- responseName),
+ - the OBJECT IDENTIFIER (if any) assigned to the responseName (note
+ that the same OBJECT IDENTIFIER my be used for both the
+ requestName and responseName),
- the format of the contents of the requestValue and responseValue
(if any), and
-
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-
- the semantics of the operation.
4.13. IntermediateResponse Message
While the Search operation provides a mechanism to return multiple
- response messages for a single search request, other operations, by
+ response messages for a single Search request, other operations, by
nature, do not provide for multiple response messages.
The IntermediateResponse message provides a general mechanism for
defining single-request/multiple-response operations in LDAP. This
- message is intended to be used in conjunction with the extended
+ message is intended to be used in conjunction with the Extended
operation to define new single-request/multiple-response operations
or in conjunction with a control when extending existing LDAP
- operations in a way that requires them to return intermediate
+ operations in a way that requires them to return Intermediate
response information.
- It is intended that the definitions and descriptions of extended
+ It is intended that the definitions and descriptions of Extended
operations and controls that make use of the IntermediateResponse
message will define the circumstances when an IntermediateResponse
message can be sent by a server and the associated meaning of an
IntermediateResponse message sent in a particular circumstance.
- Similarly, it is intended that clients will explicitly solicit
- IntermediateResponse messages by issuing operations that specifically
- call for their return.
- IntermediateResponse ::= [APPLICATION 25] SEQUENCE {
- responseName [0] LDAPOID OPTIONAL,
- responseValue [1] OCTET STRING OPTIONAL }
+ IntermediateResponse ::= [APPLICATION 25] SEQUENCE {
+ responseName [0] LDAPOID OPTIONAL,
+ responseValue [1] OCTET STRING OPTIONAL }
IntermediateResponse messages SHALL NOT be returned to the client
unless the client issues a request that specifically solicits their
- return. This document defines two forms of solicitation: extended
- operation and request control.
+ return. This document defines two forms of solicitation: Extended
+ operation and request control. IntermediateResponse messages are
+ specified in documents describing the manner in which they are
+ solicited (i.e. in the Extended operation or request control
+ specification that uses them). These specifications include:
- Although the responseName and responseValue are optional in some
- circumstances, generally speaking IntermediateResponse messages have
- a predefined responseName and a responseValue. The value of the
- responseName (if present), the syntax of the responseValue (if
- present) and the semantics associated with a particular
- IntermediateResponse message MUST be specified in documents
- describing the extended operation or request control that uses them.
+ - the OBJECT IDENTIFIER (if any) assigned to the responseName,
+
+ - the format of the contents of the responseValue (if any), and
+
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+\f
+ Lightweight Directory Access Protocol Version 3
+
+
+ - the semantics associated with the IntermediateResponse message.
+
+ Extensions that allow the return of multiple types of
+ IntermediateResponse messages SHALL identify those types using unique
+ responseName values (note that one of these may specify no value).
+
Sections 4.13.1 and 4.13.2 describe additional requirements on the
inclusion of responseName and responseValue in IntermediateResponse
messages.
A single-request/multiple-response operation may be defined using a
single ExtendedRequest message to solicit zero or more
IntermediateResponse messages of one or more kinds followed by an
- ExtendedResponse message.
+ ExtendedResponse message.
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- Lightweight Directory Access Protocol Version 3
-
- An extended operation that defines the return of multiple kinds of
- IntermediateResponse messages MUST provide and document a mechanism
- for the client to distinguish the kind of IntermediateResponse
- message being sent. This SHALL be accomplished by using different
- responseName values for each type of IntermediateResponse message
- associated with the extended operation or by including identifying
- information in the responseValue of each type of IntermediateResponse
- message associated with the extended operation.
-
-
4.13.2. Usage with LDAP Request Controls
- Any LDAP operation may be extended by the addition of one or more
- controls ([RFC2251] Section 4.1.12). A control's semantics may
- include the return of zero or more IntermediateResponse messages
- prior to returning the final result code for the operation. One or
- more kinds of IntermediateResponse messages may be sent in response
- to a request control.
+ A control's semantics may include the return of zero or more
+ IntermediateResponse messages prior to returning the final result
+ code for the operation. One or more kinds of IntermediateResponse
+ messages may be sent in response to a request control.
All IntermediateResponse messages associated with request controls
SHALL include a responseName. This requirement ensures that the
included in a request for any LDAP operation or
- one or more controls using IntermediateResponse messages are
- included in a request with an LDAP extended operation that uses
+ included in a request with an LDAP Extended operation that uses
IntermediateResponse messages.
-
- A request control that defines the return of multiple kinds of
- IntermediateResponse messages MUST provide and document a mechanism
- for the client to distinguish the kind of IntermediateResponse
- message being sent. This SHALL be accomplished by using different
- responseName values for each type of IntermediateResponse message
- associated with the request control or by including identifying
- information in the responseValue of each type of IntermediateResponse
- message associated with the request control.
4.14. StartTLS Operation
- The Start Transport Layer Security (StartTLS) operation provides the
- ability to establish Transport Layer Security ([TLS]) on an LDAP
- connection. The StartTLS operation is defined using the extended
- operation mechanism described in Section 4.12.
+ The Start Transport Layer Security (StartTLS) operation's purpose is
+ to initiate installation of a TLS layer. The StartTLS operation is
+ defined using the Extended operation mechanism described in Section
+ 4.12.
+
+
+
+
+
+
+
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+ Lightweight Directory Access Protocol Version 3
+
4.14.1. StartTLS Request
A client requests TLS establishment by transmitting a StartTLS
request PDU to the server. The StartTLS request is defined in terms
-
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-
of an ExtendedRequest. The requestName is "1.3.6.1.4.1.1466.20037",
and the requestValue field is always absent.
- The client MUST NOT send any PDUs on this connection following this
- request until it receives a StartTLS extended response and completes
- TLS negotiations.
+ The client MUST NOT send any PDUs at this LDAP message layer
+ following this request until it receives a StartTLS Extended response
+ and, in the case of a successful response, completes TLS
+ negotiations.
+
+ Detected sequencing problems (particularly those detailed in Section
+ 3.1.1 of [AuthMeth]) result in the resultCode being set to
+ operationsError.
+
+ If the server does not support TLS (whether by design or by current
+ configuration), it returns with the resultCode set to protocolError
+ as described in Section 4.12.
4.14.2. StartTLS Response
When a StartTLS request is made, servers supporting the operation
MUST return a StartTLS response PDU to the requestor. The
- responseName is also "1.3.6.1.4.1.1466.20037", and the responseValue
- field is absent.
-
- The server provides a resultCode field to either success or one of
- the other values outlined in Section 4.14.2.2.
+ responseName, if present, is also "1.3.6.1.4.1.1466.20037". The
+ responseValue is absent.
-
-4.14.2.1. "Success" Response
+ If the server is willing and able to negotiate TLS, it returns with
+ the resultCode set to success. 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 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 indicate so by
+ returning with the resultCode set to unavailable.
- 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].
+
+4.14.3. Removal of the TLS Layer
+
+ Either the client or server MAY remove the TLS layer and leave the
+ LDAP message layer intact by sending and receiving a TLS closure
+ alert.
- If the server does not support TLS (whether by design or by current
- configuration), it MUST return the protocolError resultCode. The
- client's current association is unaffected if the server does not
- support TLS. The client may proceed with any LDAP operation, or it
- may close the connection.
+ The initiating protocol peer sends the TLS closure alert. If it
+ wishes to leave the LDAP message layer intact, it then MUST cease to
+ send further PDUs and MUST ignore any received LDAP PDUs until it
+ receives a TLS closure alert from the other peer.
- The server MUST return unavailable if it supports TLS but cannot
- establish a TLS connection for some reason, e.g. the certificate
+ Once the initiating protocol peer receives a TLS closure alert from
+ the other peer it MAY send and receive LDAP PDUs.
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+\f
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- 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 LDAP connection.
-
-
-4.14.3. Closing a TLS Connection
-
- Two forms of TLS connection closure -- graceful and abrupt -- are
- supported. These do not involve LDAP PDUs, but are preformed at the
- underlying layers.
+ When a protocol peer receives the initial TLS closure alert, it may
+ choose to allow the LDAP message layer to remain intact. In this
+ case, it MUST immediately transmit a TLS closure alert. Following
+ this, it MAY send and receive LDAP PDUs.
-4.14.3.1. Graceful Closure
+ Protocol peers MAY terminate the LDAP session after sending or
+ receiving a TLS closure alert.
- Either the client or server MAY terminate the TLS connection and
- leave the LDAP connection intact by sending and receiving a TLS
- closure alert.
+ After the TLS layer has been removed, the server MUST NOT send
+ responses to any request message received before the TLS closure
+ 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.
- The initiating protocol peer sends the TLS closure alert. If it
- wishes to leave the LDAP connection intact, it then MUST cease to
- send further PDUs and MUST ignore any received PDUs until it receives
- a TLS closure alert from the other peer.
- Once the initiating protocol peer receives a TLS closure alert from
- the other peer it MAY send and receive LDAP PDUs.
+5. Protocol Encoding, Connection, and Transfer
- When a protocol peer receives the initial TLS closure alert, it may
- choose to allow the underlying LDAP connection to remain intact. In
- this case, it MUST immediately transmit a TLS closure alert.
- Following this, it MAY send and receive LDAP PDUs.
+ This protocol is designed to run over connection-oriented, reliable
+ transports, where the data stream is divided into octets (8-bit
+ units), with each octet and each bit being significant.
- Protocol peers MAY drop the underlying LDAP connection after sending
- or receiving a TLS closure alert.
-
- After the TLS connection has been closed, the server MUST NOT send
- responses to any request message received before the TLS closure.
- Thus, clients wishing to receive responses to messages sent while the
- TLS connection is intact MUST wait for those message responses before
- sending the TLS closure alert.
+ One underlying service, LDAP over TCP, is defined in Section
+ 5.2. 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.
+ Specifications detailing other mappings may encounter various
+ obstacles.
+ Implementations of LDAP over TCP MUST implement the mapping as
+ described in Section 5.2.
-4.14.3.2. Abrupt Closure
-
- Either the client or server MAY abruptly close the TLS connection by
- dropping the underlying transfer protocol connection. In this
- circumstance, a server MAY send the client a Notice of Disconnection
- before dropping the underlying LDAP connection. Outstanding
- operations are handled as specified in Section 5.2.
+ This table illustrates the relationship between the different layers
+ involved in an exchange between two protocol peers:
+ +----------------------+
+ | LDAP message layer |
+ +----------------------+ > LDAP PDUs
+ +----------------------+ < data
+ | SASL layer |
+ +----------------------+ > SASL-protected data
+ +----------------------+ < data
+ | TLS layer |
+ Application +----------------------+ > TLS-protected data
+ ------------+----------------------+ < data
+ Transport | transport connection |
+ +----------------------+
-5. Protocol Element Encodings and Transfer
+
+
+
+
+
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+\f
Lightweight Directory Access Protocol Version 3
-
- One underlying service, LDAP over TCP, is defined here. This service
- is generally applicable to applications providing or consuming X.500-
- based directory services on the Internet.
-
- Implementations of LDAP over TCP MUST implement the mapping as
- described in Section 5.2.1
-
5.1. Protocol Encoding
-
+
The protocol elements of LDAP SHALL be encoded for exchange using the
Basic Encoding Rules [BER] of [ASN.1] with the following
restrictions:
OCTET STRING values, such as attribute values, unless otherwise
stated.
-
-5.2. Transfer Protocols
-
- This protocol is designed to run over connection-oriented, reliable
- transports, with all 8 bits in an octet being significant in the data
- stream. Protocol operations are tied to a connection, thus if the
- connection is closed or dropped, the operation is aborted. When this
- happens, any outstanding operations on the server are, when possible,
- abandoned, and when not possible, completed without transmission of
- the response. Also, if the connection is closed or dropped, the
- client MUST NOT assume that any outstanding requests which modified
- the Directory have succeeded or failed.
-
-
-5.2.1. Transmission Control Protocol (TCP)
+
+5.2. Transmission Control Protocol (TCP)
The encoded LDAPMessage PDUs are mapped directly onto the [TCP]
bytestream using the BER-based encoding described in Section 5.1. It
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
-
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-
instead provide a listener on a different port number. Clients MUST
support contacting servers on any valid TCP port.
+5.3. Termination of the LDAP session
+
+ Termination of the LDAP session is typically initiated by the client
+ sending an UnbindRequst (Section 4.3), or by the server sending a
+ Notice of Disconnection (Section 4.4.1). In these cases each protocol
+ peer gracefully terminates the LDAP session by ceasing exchanges at
+ the LDAP message layer, tearing down any SASL layer, tearing down any
+ TLS layer, and closing the transport connection.
+
+ A protocol peer may determine that the continuation of any
+ communication would be pernicious, and in this case may abruptly
+ terminate the session by ceasing communication and closing the
+ transport connection.
+
+ In either case, when the LDAP session is terminated, uncompleted
+ operations are handled as specified in Section 3.1.
+
+
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+\f
+ Lightweight Directory Access Protocol Version 3
+
+
+
6. Security Considerations
This version of the protocol provides facilities for simple
authentication using a cleartext password, as well as any [SASL]
- mechanism. SASL allows for integrity and privacy services to be
- negotiated.
+ mechanism. Installing SASL and/or TLS layers can provide integrity
+ and other data security services.
It is also permitted that the server can return its credentials to
the client, if it chooses to do so.
Servers are encouraged to prevent directory modifications by clients
that have authenticated anonymously [AuthMeth].
- Requirements of authentication methods, SASL mechanisms, and TLS are
- described in [AuthMeth].
+ Security considerations for authentication methods, SASL mechanisms,
+ and TLS are described in [AuthMeth].
It should be noted that SASL authentication exchanges do not provide
data confidentiality nor integrity protection for the version or name
- fields of the bind request nor the resultCode, diagnosticMessage, or
- referral fields of the bind response nor of any information contained
- in controls attached to bind request or responses. Thus information
+ fields of the BindRequest nor the resultCode, diagnosticMessage, or
+ referral fields of the BindResponse nor of any information contained
+ in controls attached to Bind requests or responses. Thus information
contained in these fields SHOULD NOT be relied on unless otherwise
protected (such as by establishing protections at the transport
- layer).
-
- Server implementors should plan for the possibility of an identity
- associated with an LDAP connection 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
+ 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 session, 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
is to be provided to multiple clients, since servers may have access
control policies which prevent the return of entries or attributes in
- search results except to particular authenticated clients. For
+ Search results except to particular authenticated clients. For
example, caches could serve result information only to the client
whose request caused it to be in the cache.
- Servers may return referrals or search result references which
+ Servers may return referrals or Search result references which
redirect clients to peer servers. It is possible for a rogue
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
+ confidentiality measures are not in place. Clients are advised to
+ reject referrals from the StartTLS operation.
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Lightweight Directory Access Protocol Version 3
- confidentiality measures are not in place. Clients are advised to
- reject referrals from the StartTLS operation.
The matchedDN and diagnosticMessage fields, as well as some
resultCode values (e.g., attributeOrValueExists and
- entryAlreadyExists), could disclose the presence the specific data in
- 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.
-
+ entryAlreadyExists), could disclose the presence or absence of
+ specific data in 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. A number of LDAP security advisories are
- available through [CERT].
+ length protocol encodings. Invalid protocol encodings include: BER
+ encoding exceptions, format string and UTF-8 encoding exceptions,
+ overflow exceptions, integer value exceptions, and binary mode on/off
+ flag exceptions. The LDAPv3 PROTOS [PROTOS-LDAP] test suite provides
+ excellent examples of these exceptions and test cases used to
+ discover flaws.
+
+ In the event that a protocol peer senses an attack which in its
+ nature could cause damage due to further communication at any layer
+ in the LDAP session, the protocol peer should abruptly terminate the
+ LDAP session as described in Section 5.3.
7. Acknowledgements
This document is based on RFC 2251 by Mark Wahl, Tim Howes, and Steve
- Kille. It is also based on RFC 2830 by Jeff Hodges, RL "Bob" Morgan,
- and Mark Wahl. It is also based on [LIMR] by Roger Harrison, and Kurt
- Zeilenga. Notable amounts of technical reviews and content were
- provided by Kurt Zeilenga, Steven Legg, and Hallvard Furuseth. Their
- work along with the input of individuals of the IETF ASID, LDAPEXT,
- LDUP, LDAPBIS, and other Working Groups is gratefully acknowledged.
+ Kille. RFC 2251 was a product of the IETF ASID Working Group.
+
+ It is also based on RFC 2830 by Jeff Hodges, RL "Bob" Morgan, and
+ Mark Wahl. RFC 2830 was a product of the IETF LDAPEXT Working Group.
+
+ 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 IETF LDAPBIS Working Group.
+ Significant contributors of technical review and content include Kurt
+ Zeilenga, Steven Legg, and Hallvard Furuseth.
8. Normative References
Level Security Mechanisms", draft-ietf-ldapbis-authmeth-
xx.txt, (a work in progress).
+
+
+
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+\f
+ Lightweight Directory Access Protocol Version 3
+
[BER] ITU-T Rec. X.690 (07/2002) | ISO/IEC 8825-1:2002,
"Information technology - ASN.1 encoding rules:
Specification of Basic Encoding Rules (BER), Canonical
[Keyword] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", RFC 2119, March 1997.
-
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- Lightweight Directory Access Protocol Version 3
-
[LDAPDN] Zeilenga, K., "LDAP: String Representation of
Distinguished Names", draft-ietf-ldapbis-dn-xx.txt, (a
[LDAPURL] Smith, M., "LDAP: Uniform Resource Locator", draft-ietf-
ldapbis-url-xx.txt, (a work in progress).
- [LIMR] Harrison, R., and K. Zeilenga, "The Lightweight Directory
- Access Protocol (LDAP) Intermediate Response Message",
- draft-rharrison-ldap-intermediate-resp-xx.txt (a work in
- progress).
-
[Models] Zeilenga, K., "LDAP: Directory Information Models", draft-
ietf-ldapbis-models-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.
+
+
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+\f
+ Lightweight Directory Access Protocol Version 3
+
[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),
[URI] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
Resource Identifiers (URI): Generic Syntax", RFC 2396,
- August 1998.
-
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- Lightweight Directory Access Protocol Version 3
-
+ August 1998.
[UTF-8] Yergeau, F., "UTF-8, a transformation format of ISO
10646", STD63 and RFC3629, November 2003.
9. Informative References
- [CERT] The CERT(R) Center, http://www.cert.org
+ [Glossary] The Unicode Consortium, "Unicode Glossary",
+ <http://www.unicode.org/glossary/>.
+
+ [CharModel] Whistler, K. and M. Davis, "Unicode Technical Report
+ #17, Character Encoding Model", UTR17,
+ <http://www.unicode.org/unicode/reports/tr17/>, August
+ 2000.
+
+ [PROTOS-LDAP] University of Oulu, "PROTOS Test-Suite: c06-ldapv3"
+ <http://www.ee.oulu.fi/research/ouspg/protos/testing/c06/l
+ dapv3/>
[PortReg] IANA, "Port Numbers",
http://www.iana.org/assignments/port-numbers
It is requested that the IANA update the LDAP Protocol Mechanism
registry to indicate that this document and [AuthMeth] provides the
- definitive technical specification for the Start TLS
- (1.3.6.1.4.1.1466.20037) extended operation.
+ definitive technical specification for the StartTLS
+ (1.3.6.1.4.1.1466.20037) Extended operation.
+
+Sermersheim Internet-Draft - Expires Aug 2005 Page 44
+\f
+ Lightweight Directory Access Protocol Version 3
+
It is requested that the IANA update the occurrence of "RFC XXXX" in
Appendix B with this RFC number at publication.
+
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Lightweight Directory Access Protocol Version 3
Appendix A - LDAP Result Codes
[LDAPIANA]. Client implementations SHALL treat any result code which
they do not recognize as an unknown error condition.
+ Servers may substitute some result codes due to access controls which
+ prevent their disclosure.
+
A.1 Non-Error Result Codes
These result codes (called "non-error" result codes) do not indicate
an error condition:
success (0),
+ compareFalse (5),
compareTrue (6),
- compareFalse (7),
referral (10), and
saslBindInProgress (14).
result codes).
The referral and saslBindInProgress result codes indicate the client
- is required to take additional action to complete the operation.
+ needs to take additional action to complete the operation.
A.2 Result Codes
success (0)
Indicates the successful completion of an operation. Note:
- this code is not used with the compare operation. See
- compareTrue (5) and compareFalse (6).
+ this code is not used with the Compare operation. See
+ compareFalse (5) and compareTrue (6).
operationsError (1)
Indicates that the operation is not properly sequenced with
relation to other operations (of same or different type).
For example, this code is returned if the client attempts to
- StartTLS [TLS] while there are other operations outstanding
- or if TLS was already established.
+ StartTLS [TLS] while there are other uncompleted operations
+ or if a TLS layer was already installed.
protocolError (2)
- Indicates the server received data which has incorrect
- structure.
-
- For bind operation only, this code is also used to indicate
- that the server does not support the requested protocol
- version.
+ Indicates the server received data which is not well-formed.
+
+
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+\f
Lightweight Directory Access Protocol Version 3
+ For Bind operation only, this code is also used to indicate
+ that the server does not support the requested protocol
+ version.
+
+ For Extended operations only, this code is also used to
+ indicate that the server does not support (by design or
+ configuration) the Extended operation associated with the
+ requestName.
+
+ For request operations specifying multiple controls, this may
+ be used to indicate that the server cannot ignore the order
+ of the controls as specified, or that the combination of the
+ specified controls is invalid or unspecified.
+
timeLimitExceeded (3)
Indicates that the time limit specified by the client was
exceeded before the operation could be completed.
exceeded before the operation could be completed.
compareFalse (5)
- Indicates that the compare operation has successfully
- completed and the assertion has evaluated to FALSE.
+ Indicates that the Compare operation has successfully
+ completed and the assertion has evaluated to FALSE or
+ Undefined.
compareTrue (6)
- Indicates that the compare operation has successfully
+ Indicates that the Compare operation has successfully
completed and the assertion has evaluated to TRUE.
authMethodNotSupported (7)
Indicates that the authentication method or mechanism is not
supported.
- strongAuthRequired (8)
- Indicates that 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.
+ strongerAuthRequired (8)
+ Indicates the server requires strong(er) authentication in
+ order to complete the operation.
+
+ When used with the Notice of Disconnection operation, this
+ code indicates that the server has detected that an
+ established security association between the client and
+ server has unexpectedly failed or been compromised.
referral (10)
Indicates that a referral needs to be chased to complete the
Indicates that an administrative limit has been exceeded.
unavailableCriticalExtension (12)
- Indicates that the server is unable or unwilling to perform a
- critical control (see Section 4.1.11).
+ Indicates a critical control is unrecognized (see Section
+ 4.1.11).
+
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+\f
+ Lightweight Directory Access Protocol Version 3
+
confidentialityRequired (13)
Indicates that data confidentiality protections are required.
Indicates that a request field contains an unrecognized
attribute description.
-
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- Lightweight Directory Access Protocol Version 3
-
inappropriateMatching (18)
- Indicates that an attempt was made, e.g. in an assertion, to
+ Indicates that an attempt was made (e.g. in an assertion) to
use a matching rule not defined for the attribute type
concerned.
not conform to the required syntax or contains attribute
values which do not conform to the syntax of the attribute's
type.
+
+
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+ Lightweight Directory Access Protocol Version 3
+
aliasDereferencingProblem (36)
Indicates that a problem occurred while dereferencing an
insufficientAccessRights (50)
Indicates that the client does not have sufficient access
rights to perform the operation.
-
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- Lightweight Directory Access Protocol Version 3
-
busy (51)
Indicates that the server is too busy to service the
entryAlreadyExists (68)
Indicates that the request cannot be fulfilled (added, moved,
or renamed) as the target entry already exists.
+
+
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+\f
+ Lightweight Directory Access Protocol Version 3
+
objectClassModsProhibited (69)
Indicates that an attempt to modify the object class(es) of
modify the structural object class of an entry.
affectsMultipleDSAs (71)
- Indicates that the operation cannot be completed as it
- affects multiple servers (DSAs).
+ Indicates that the operation cannot be performed as it would
+ affect multiple servers (DSAs).
other (80)
Indicates the server has encountered an internal error.
+
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+\f
Lightweight Directory Access Protocol Version 3
Appendix B - Complete ASN.1 Definition
This appendix is normative.
Lightweight-Directory-Access-Protocol-V3
- -- Copyright (C) The Internet Society (2003). This version of
+ -- Copyright (C) The Internet Society (2004). This version of
-- this ASN.1 module is part of RFC XXXX; see the RFC itself
-- for full legal notices.
DEFINITIONS
abandonRequest AbandonRequest,
extendedReq ExtendedRequest,
extendedResp ExtendedResponse,
- intermediateResponse IntermediateResponse
- ... },
+ ...,
+ intermediateResponse IntermediateResponse },
controls [0] Controls OPTIONAL }
MessageID ::= INTEGER (0 .. maxInt)
LDAPDN ::= LDAPString -- Constrained to <distinguishedName>
-- [LDAPDN]
- RelativeLDAPDN ::= LDAPString -- Constrained to <name-component>
+
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Lightweight Directory Access Protocol Version 3
+ RelativeLDAPDN ::= LDAPString -- Constrained to <name-component>
-- [LDAPDN]
AttributeDescription ::= LDAPString
MatchingRuleId ::= LDAPString
+
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+ Lightweight Directory Access Protocol Version 3
+
LDAPResult ::= SEQUENCE {
resultCode ENUMERATED {
success (0),
compareFalse (5),
compareTrue (6),
authMethodNotSupported (7),
- strongAuthRequired (8),
+ strongerAuthRequired (8),
-- 9 reserved --
referral (10),
adminLimitExceeded (11),
-- 35 reserved for undefined isLeaf --
aliasDereferencingProblem (36),
-- 37-47 unused --
-
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- Lightweight Directory Access Protocol Version 3
-
inappropriateAuthentication (48),
invalidCredentials (49),
insufficientAccessRights (50),
referral [3] Referral OPTIONAL }
Referral ::= SEQUENCE SIZE (1..MAX) OF uri URI
+
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+\f
+ Lightweight Directory Access Protocol Version 3
+
URI ::= LDAPString -- limited to characters permitted in
-- URIs
COMPONENTS OF LDAPResult,
serverSaslCreds [7] OCTET STRING OPTIONAL }
-
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- Lightweight Directory Access Protocol Version 3
-
UnbindRequest ::= [APPLICATION 2] NULL
SearchRequest ::= [APPLICATION 3] SEQUENCE {
scope ENUMERATED {
baseObject (0),
singleLevel (1),
- wholeSubtree (2) },
+ wholeSubtree (2),
+ ... },
derefAliases ENUMERATED {
neverDerefAliases (0),
derefInSearching (1),
filter Filter,
attributes AttributeSelection }
- AttributeSelection ::= SEQUENCE OF selection LDAPString
- -- constrained to <attributeSelection>
- -- in section 4.5.1.
+ AttributeSelection ::= SEQUENCE OF selector LDAPString
+ -- The LDAPString is constrained to
+ -- <attributeSelector> in Section 4.5.1.7
+
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+\f
+ Lightweight Directory Access Protocol Version 3
+
Filter ::= CHOICE {
and [0] SET SIZE (1..MAX) OF filter Filter,
or [1] SET SIZE (1..MAX) OF filter Filter,
lessOrEqual [6] AttributeValueAssertion,
present [7] AttributeDescription,
approxMatch [8] AttributeValueAssertion,
- extensibleMatch [9] MatchingRuleAssertion }
+ extensibleMatch [9] MatchingRuleAssertion,
+ ... }
SubstringFilter ::= SEQUENCE {
type AttributeDescription,
- -- at least one must be present,
- -- initial and final can occur at most once
substrings SEQUENCE SIZE (1..MAX) OF substring CHOICE {
- initial [0] AssertionValue,
+ initial [0] AssertionValue, -- can occur at most once
any [1] AssertionValue,
- final [2] AssertionValue } }
+ final [2] AssertionValue } -- can occur at most once
+ }
MatchingRuleAssertion ::= SEQUENCE {
matchingRule [1] MatchingRuleId OPTIONAL,
objectName LDAPDN,
attributes PartialAttributeList }
-
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- Lightweight Directory Access Protocol Version 3
-
PartialAttributeList ::= SEQUENCE OF
partialAttribute PartialAttribute
operation ENUMERATED {
add (0),
delete (1),
- replace (2) },
+ replace (2),
+ ... },
modification PartialAttribute } }
ModifyResponse ::= [APPLICATION 7] LDAPResult
AddRequest ::= [APPLICATION 8] SEQUENCE {
entry LDAPDN,
attributes AttributeList }
+
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+ Lightweight Directory Access Protocol Version 3
+
AttributeList ::= SEQUENCE OF attribute Attribute
ExtendedResponse ::= [APPLICATION 24] SEQUENCE {
COMPONENTS OF LDAPResult,
responseName [10] LDAPOID OPTIONAL,
-
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- Lightweight Directory Access Protocol Version 3
-
responseValue [11] OCTET STRING OPTIONAL }
+ IntermediateResponse ::= [APPLICATION 25] SEQUENCE {
+ responseName [0] LDAPOID OPTIONAL,
+ responseValue [1] OCTET STRING OPTIONAL }
+
END
-
-
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+\f
Lightweight Directory Access Protocol Version 3
Appendix C - Changes
This appendix is non-normative.
- This appendix summarizes substantive changes made to RFC 2251 and RFC
- 2830.
+ This appendix summarizes substantive changes made to RFC 2251, RFC
+ 2830, and RFC 3771.
-C.1 Changes made to made to RFC 2251:
+C.1 Changes made to RFC 2251:
This section summarizes the substantive changes made to Sections 1,
2, 3.1, and 4 through the remainder of RFC 2251. Readers should
sections.
-C.1.1 Section 1
+C.1.1 Section 1 (Status of this Memo)
- Removed IESG note. Post publication of RFC 2251, mandatory LDAP
authentication mechanisms have been standardized which are
mechanisms.
-C.1.2 Section 3.1 and others
+C.1.2 Section 3.1 (Protocol Model) and others
- Removed notes giving history between LDAP v1, v2 and v3. Instead,
added sufficient language so that this document can stand on its
own.
-C.1.3 Section 4
+C.1.3 Section 4 (Elements of Protocol)
- Clarified where the extensibility features of ASN.1 apply to the
- protocol. This change also affected various ASN.1 types.
+ protocol. This change affected various ASN.1 types by the
+ inclusion of ellipses (...) to certain elements.
- Removed the requirement that servers which implement version 3 or
later MUST provide the 'supportedLDAPVersion' attribute. This
statement provided no interoperability advantages.
-C.1.4 Section 4.1.1
+C.1.4 Section 4.1.1 (Message Envelope)
- There was a mandatory requirement for the server to return a
- Notice of Disconnection and drop the connection when a PDU is
- malformed in a certain way. This has been clarified such that the
- server SHOULD return the Notice of Disconnection, and MUST drop
- the connection.
+ Notice of Disconnection and drop the transport connection when a
+ PDU is malformed in a certain way. This has been updated such that
+ the server SHOULD return the Notice of Disconnection, and MUST
+ terminate the LDAP Session.
-C.1.5 Section 4.1.1.1
+C.1.5 Section 4.1.1.1 (Message ID)
- - Clarified that the messageID of requests MUST be non-zero.
-
-
+ - Required that the messageID of requests MUST be non-zero as the
+ zero is reserved for Notice of Disconnection.
-Sermersheim Internet-Draft - Expires Aug 2004 Page 52 \f
+Sermersheim Internet-Draft - Expires Aug 2005 Page 57
+\f
Lightweight Directory Access Protocol Version 3
- - Clarified when it is and isn't appropriate to return an already
+ - Specified when it is and isn't appropriate to return an already
used message id. RFC 2251 accidentally imposed synchronous server
behavior in its wording of this.
-C.1.6 Section 4.1.2
+C.1.6 Section 4.1.2 (String Types)
- 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 (Binary Option) 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 (Attribute)
- 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 (Result Message)
- Renamed "errorMessage" to "diagnosticMessage" as it is allowed to
be sent for non-error results.
- Moved some language into Appendix A, and refer the reader there.
- Allowed matchedDN to be present for other result codes than those
listed in RFC 2251.
+ - renamed the code "strongAuthRequired" to "strongerAuthRequired" to
+ clarify that this code may often be returned to indicate that a
+ stronger authentication is needed to perform a given operation.
-C.1.12 Section 4.1.11
+C.1.10 Section 4.1.11 (Referral)
- 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.
-
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- Lightweight Directory Access Protocol Version 3
-
+ - Removed imperatives which required clients to use URLs in specific
+ ways to progress an operation. These did nothing for
+ interoperability.
-C.1.13 Section 4.1.12
+C.1.11 Section 4.1.12 (Controls)
- Specified how control values defined in terms of ASN.1 are to be
encoded.
+
+Sermersheim Internet-Draft - Expires Aug 2005 Page 58
+\f
+ Lightweight Directory Access Protocol Version 3
+
- Noted that the criticality field is only applied to request
- messages (except unbindRequest), and must be ignored when present
- on response messages and unbindRequest.
- - Added language regarding combinations of controls on a message.
+ messages (except UnbindRequest), and must be ignored when present
+ on response messages and UnbindRequest.
+ - Added language regarding combinations of controls and the ordering
+ of controls on a message.
+ - 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
prepared" in the eighth paragraph to reflect that both client and
server implementations must be able to handle this (as both parse
controls).
-C.1.14 Section 4.2
+C.1.12 Section 4.2 (Bind Operation)
- Mandated that servers return protocolError when the version is not
supported.
- - Clarified behavior when the simple authentication is used, the
+ - Disambiguated behavior when the simple authentication is used, the
name is empty and the password is non-empty.
- - Required servers to not dereference aliases for bind. This was
+ - Required servers to not dereference aliases for Bind. This was
added for consistency with other operations and to help ensure
data consistency.
- Required that textual passwords be transferred as UTF-8 encoded
different clients.
-C.1.15 Section 4.2.1
+C.1.13 Section 4.2.1 (Sequencing of the Bind Request)
- This section was largely reorganized for readability and language
was added to clarify the authentication state of failed and
- abandoned bind operations.
+ abandoned Bind operations.
- Removed: "If a SASL transfer encryption or integrity mechanism has
been negotiated, that mechanism does not support the changing of
credentials from one identity to another, then the client MUST
instead establish a new connection."
- Each SASL negotiation is, generally, independent of other SASL
- negotiations. If there were dependencies between multiple
- negotiations of a particular mechanism, the mechanism technical
- specification should detail how applications are to deal with
- them. LDAP should not require any special handling. And if an LDAP
- client had used such a mechanism, it would have the option of
- using another mechanism.
+ If there are dependencies between multiple negotiations of a
+ particular SASL mechanism, the technical specification for that
+ SASL mechanism details how applications are to deal with them.
+ LDAP should not require any special handling.
- 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
+ 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 (Bind Response)
-
+ - Moved most error-related text to Appendix A, and added text
+ regarding certain errors used in conjunction with the Bind
+ operation.
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+Sermersheim Internet-Draft - Expires Aug 2005 Page 59
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Lightweight Directory Access Protocol Version 3
- - Moved most error-related text to Appendix A, and added text
- regarding certain errors used in conjunction with the bind
- operation.
- Prohibited the server from specifying serverSaslCreds when not
appropriate.
-C.1.17 Section 4.3
+C.1.15 Section 4.3 (Unbind Operation)
- - Required both peers to cease transmission and close the connection
- for the unbind operation.
+ - Specified that both peers are to cease transmission and terminate
+ the LDAP session for the Unbind operation.
-C.1.18 Section 4.4
+C.1.16 Section 4.4 (Unsolicited Notification)
- Added instructions for future specifications of Unsolicited
Notifications.
-C.1.19 Section 4.5.1
+C.1.17 Section 4.5.1 (Search Request)
- 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
first, and 'final' (if present) must be listed last.
- - Clarified the semantics of the derefAliases choices.
+ - Disambiguated the semantics of the derefAliases choices. There was
+ question as to whether derefInSearching applied to the base object
+ in a wholeSubtree Search.
- Added instructions for equalityMatch, substrings, greaterOrEqual,
lessOrEqual, and approxMatch.
-C.1.20 Section 4.5.2
+C.1.18 Section 4.5.2 (Search Result)
- Recommended that servers not use attribute short names when it
knows they are ambiguous or may cause interoperability problems.
implementation.
-C.1.21 Section 4.5.3
+C.1.19 Section 4.5.3 (Continuation References in the Search Result)
- Made changes similar to those made to Section 4.1.11.
-C.1.22 Section 4.5.3.1
+
+
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+Sermersheim Internet-Draft - Expires Aug 2005 Page 60
+\f
Lightweight Directory Access Protocol Version 3
+C.1.20 Section 4.5.3.1 (Example)
- Fixed examples to adhere to changes made to Section 4.5.3.
-C.1.23 Section 4.6
-
- - 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
- equality is used.
+C.1.21 Section 4.6 (Modify Operation)
+
- Replaced AttributeTypeAndValues with Attribute as they are
equivalent.
- - Clarified what type of modification changes might temporarily
- violate schema.
+ - Specified the types of modification changes which might
+ temporarily violate schema. Some readers were under the impression
+ that any temporary schema violation was allowed.
-C.1.24 Section 4.7
+C.1.22 Section 4.7 (Add Operation)
- Aligned Add operation with X.511 in that the attributes of the RDN
are used in conjunction with the listed attributes to create the
entry. Previously, Add required that the distinguished values be
present in the listed attributes.
+ - Removed requirement that the objectClass attribute MUST be
+ specified as some DSE types do not require this attribute.
+ Instead, generic wording was added, requiring the added entry to
+ adhere to the data model.
+ - Removed recommendation regarding placement of objects. This is
+ covered in the data model document.
-C.1.25 Section 4.9
+C.1.23 Section 4.9 (Modify DN Operation)
- - Required servers to not dereference aliases for modify DN. This
+ - Required servers to not dereference aliases for Modify DN. This
was added for consistency with other operations and to help ensure
data consistency.
- - Allow modify DN to fail when moving between naming contexts.
- - Specified what happens when the attributes of the newrdn are no
+ - Allow Modify DN to fail when moving between naming contexts.
+ - Specified what happens when the attributes of the newrdn are not
present on the entry.
-C.1.26 Section 4.10
+C.1.24 Section 4.10 (Compare Operation)
- - Clarified the semantics of Compare when the attribute is not
- present and when it is unknown.
- - Clarified that an Undefined compare results in a compareFalse
- resultCode.
- - Required servers to not dereference aliases for compare. This was
+ - Specified that compareFalse means that the Compare took place and
+ the result is false. There was confusion which lead people to
+ believe that an Undefined match resulted in compareFalse.
+ - Required servers to not dereference aliases for Compare. This was
added for consistency with other operations and to help ensure
data consistency.
-C.1.27 Section 4.11
+C.1.25 Section 4.11 (Abandon Operation)
- - Explained that since abandon returns no response, clients should
+ - Explained that since Abandon returns no response, clients should
not use it if they need to know the outcome.
- Specified that Abandon and Unbind cannot be abandoned.
-
-C.1.28 Section 4.12
-
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+Sermersheim Internet-Draft - Expires Aug 2005 Page 61
+\f
Lightweight Directory Access Protocol Version 3
- - Specified how values of extended operations defined in terms of
+
+C.1.26 Section 4.12 (Extended Operation)
+
+ - Specified how values of Extended operations defined in terms of
ASN.1 are to be encoded.
- - Added instructions on what extended operation specifications
+ - Added instructions on what Extended operation specifications
consist of.
- - Added a recommendation that servers advertise supported extended
+ - Added a recommendation that servers advertise supported Extended
operations.
-C.1.29 Section 5.2
+C.1.27 Section 5.2 (Transfer Protocols)
- Moved referral-specific instructions into referral-related
sections.
-C.1.30 Section 7
+C.1.28 Section 7 (Security Considerations)
- Reworded notes regarding SASL not protecting certain aspects of
- the LDAP bind PDU.
+ the LDAP Bind PDUs.
- Noted that Servers are encouraged to prevent directory
modifications by clients that have authenticated anonymously
[AuthMeth].
- Added a note regarding malformed and long encodings.
-C.1.31 Appendix A
+C.1.29 Appendix A (Complete ASN.1 Definition)
- - Added "EXTESIBILITY IMPLIED" to ASN.1 definition.
+ - Added "EXTENSIBILITY IMPLIED" to ASN.1 definition.
- Removed AttributeType. It is not used.
-C.2 Changes made to made to RFC 2830:
+C.2 Changes made to RFC 2830:
This section summarizes the substantive changes made to Sections of
RFC 2830. Readers should consult [AuthMeth] for summaries of changes
to other sections.
-C.2.1 Section 2.3
+C.2.1 Section 2.3 (Response other than "success")
- Removed wording indicating that referrals can be returned from
- StartTLS
+ StartTLS.
- 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.2.1 Section 4.13.3.1
-Sermersheim Internet-Draft - Expires Aug 2004 Page 57 \f
+Sermersheim Internet-Draft - Expires Aug 2005 Page 62
+\f
Lightweight Directory Access Protocol Version 3
+
+C.2.1 Section 4 (Closing a TLS Connection)
+
- Reworded most of this section and added the requirement that after
the TLS connection has been closed, the server MUST NOT send
responses to any request message received before the TLS closure.
+ - Removed instructions on abrupt closure as this is covered in other
+ areas of the document (specifically, Section 5.3)
-C.3 Changes made to made to [LIMR]:
+C.3 Changes made to RFC 3771:
- - In general, all technical language was transferred in whole.
- Supporting and background language seen as redundant due to its
- presence in this document was omitted.
+ - Rewrote to fit into this document. In general, semantics were
+ preserved. Supporting and background language seen as redundant
+ due to its presence in this document was omitted.
+ - Specified that Intermediate responses to a request may be of
+ different types, and one of the response types may be specified to
+ have no response value.
-
-
-
-
-
-
-
-
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+Sermersheim Internet-Draft - Expires Aug 2005 Page 63
+\f
Lightweight Directory Access Protocol Version 3
-Intellectual Property Rights
+
+
+Intellectual Property Statement
+
The IETF takes no position regarding the validity or scope of any
- intellectual property or other rights that might be claimed to
+ 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; neither does it represent that it
- has made any effort to identify any such rights. Information on the
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- 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.
-
+ 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
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+ <http://www.ietf.org/ipr>.
+
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-
+ 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 Statement
-
- Copyright (C) The Internet Society (2003). 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
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- The limited permissions granted above are perpetual and will not be
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- 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
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+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
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+ 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.
+
+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 Aug 2004 Page 59 \f
\ No newline at end of file
+Sermersheim Internet-Draft - Expires Aug 2005 Page 64
+\f
\ No newline at end of file
projects / openldap / blobdiff