Internet-Draft Editor: J. Sermersheim
Intended Category: Standard Track Novell, Inc
-Document: draft-ietf-ldapbis-protocol-27.txt Oct 2004
+Document: draft-ietf-ldapbis-protocol-30.txt Feb 2005
Obsoletes: RFCs 2251, 2830, 3771
Protocol (DAP).
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Table of Contents
1. Introduction....................................................3
- 1.1. Relationship to Obsolete Specifications.......................3
+ 1.1. Relationship to Other LDAP Specifications.....................3
2. Conventions.....................................................3
3. Protocol Model..................................................4
- 3.1 Operation and LDAP Exchange Relationship.......................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................................................7
4.1.3. Distinguished Name and Relative Distinguished Name..........7
- 4.1.4. Attribute Descriptions......................................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..................................................12
+ 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.............................................27
- 4.7. Add Operation................................................28
- 4.8. Delete Operation.............................................29
- 4.9. Modify DN Operation..........................................30
- 4.10. Compare Operation...........................................31
- 4.11. Abandon Operation...........................................32
- 4.12. Extended Operation..........................................32
- 4.13. IntermediateResponse Message................................34
- 4.13.1. Usage with LDAP ExtendedRequest and ExtendedResponse......34
- 4.13.2. Usage with LDAP Request Controls..........................35
- 4.14. StartTLS Operation..........................................35
- 5. Protocol Encoding, Connection, and Transfer....................37
- 5.2. Protocol Encoding............................................37
- 5.3. Transmission Control Protocol (TCP)..........................38
- 6. Security Considerations........................................38
- 7. Acknowledgements...............................................39
- 8. Normative References...........................................40
- 9. Informative References.........................................41
- 10. IANA Considerations...........................................42
- 11. Editor's Address..............................................42
- Appendix A - LDAP Result Codes....................................43
- A.1 Non-Error Result Codes........................................43
- A.2 Result Codes..................................................43
- Appendix B - Complete ASN.1 Definition............................48
- Appendix C - Changes..............................................54
- C.1 Changes made to RFC 2251:.....................................54
- C.2 Changes made to RFC 2830:.....................................59
- C.3 Changes made to RFC 3771:.....................................59
-
-
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+ 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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1. Introduction
The Directory is "a collection of open systems cooperating to provide
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
Information on the Unicode character encoding model can be found in
[CharModel].
+
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- The term "connection" refers to the underlying transport service used
- to carry the protocol exchange.
+ 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 "LDAP exchange" refers to the layer where LDAP PDUs are
- exchanged between protocol peers.
+ The term "SASL layer" refers to SASL services used in providing
+ security services, as well as associations established by these
+ services.
- The term "TLS layer" refers to a layer inserted between the
- connection and the LDAP exchange that utilizes Transport Layer
- Security ([TLS]) to protect the exchange of LDAP PDUs.
+ 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 "SASL layer" refers to a layer inserted between the
- connection and the LDAP exchange that utilizes Simple Authentication
- and Security Layer ([SASL]) to protect the exchange of LDAP PDUs.
+ 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.
implementations acting as a gateway to X.500 directories may need to
make multiple DAP requests to service a single LDAP request.
-
-3.1 Operation and LDAP Exchange Relationship
-
- Protocol operations are tied to an LDAP exchange. When the connection
- is closed, any uncompleted operations tied to the LDAP exchange are,
- when possible, abandoned, and when not possible, completed without
- transmission of the response. Also, when the connection is closed,
- the client MUST NOT assume that any uncompleted update operations
- tied to the LDAP exchange have succeeded or failed.
+
+
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+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
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
encapsulated in a common envelope, the LDAPMessage, which is defined
as follows:
+
+
+
+
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LDAPMessage ::= SEQUENCE {
messageID MessageID,
protocolOp CHOICE {
modifyRequest ModifyRequest,
modifyResponse ModifyResponse,
addRequest AddRequest,
-
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addResponse AddResponse,
delRequest DelRequest,
delResponse DelResponse,
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
- implementations MUST return an appropriate response to the request,
- with the resultCode set to protocolError.
+ 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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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 the messageID of any other uncompleted requests in the LDAP
- exchange. The zero value is reserved for the unsolicited notification
+ 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 in the same LDAP exchange unless it can be determined
+ earlier request in the same LDAP session unless it can be determined
that the server is no longer servicing the earlier request (e.g.
-
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- after the final response is received, or a subsequent bind
+ 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
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
is an attribute type and zero or more options.
AttributeDescription ::= LDAPString
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-- Constrained to <attributedescription>
-- [Models]
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
+ 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,
[Syntaxes] for an example.
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4.1.7. Attribute and PartialAttribute
Attributes and partial attributes consist of an attribute description
...,
vals (SIZE(1..MAX))})
- No two attribute values may be equivalent as described by Section 2.3
- of [Models]. The set of attribute values is unordered.
+ 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.
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
- containing the components of LDAPResult to indicate the final status
- of a protocol operation request.
+ 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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LDAPResult ::= SEQUENCE {
resultCode ENUMERATED {
success (0),
compareFalse (5),
compareTrue (6),
authMethodNotSupported (7),
- strongAuthRequired (8),
+ strongerAuthRequired (8),
-- 9 reserved --
referral (10),
adminLimitExceeded (11),
unavailableCriticalExtension (12),
confidentialityRequired (13),
saslBindInProgress (14),
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noSuchAttribute (16),
undefinedAttributeType (17),
inappropriateMatching (18),
diagnosticMessage LDAPString,
referral [3] Referral OPTIONAL }
+
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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 (subject to
access controls) to the name of the last entry (object or alias) used
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- in finding the target (or base) object. If no aliases were
- dereferenced while attempting to locate the entry, this will be a
- truncated form of the name provided or if aliases were dereferenced,
- of the resulting name, as defined in Section 12.5 of [X.511].
- Otherwise the matchedDN field is empty.
+ 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 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
- 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 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
+
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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.
+ 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.
- 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.
+ 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].
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- 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 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].
+ - If an alias was dereferenced, the <dn> part of the LDAP URL MUST
+ be present, with the new target object name.
- 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.
+ - 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
+ - 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
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
controlType LDAPOID,
criticality BOOLEAN DEFAULT FALSE,
controlValue OCTET STRING OPTIONAL }
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The controlType field is the dotted-decimal representation of an
OBJECT IDENTIFIER which uniquely identifies the control. This
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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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
contents of the controlValue octet string, including zero bytes. It
is absent only if there is no value information which is associated
with a control of its type. When a controlValue is defined in terms
- of ASN.1, and BER encoded according to Section 5.2, it also follows
+ 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 request controls they recognize in
dependent semantics are given in a specification, the order of a
combination of controls in the SEQUENCE is ignored. Where the order
is to be ignored but cannot be ignored by the server, the message is
-
-
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considered not well-formed and the operation fails with
protocolError.
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.
Operational, authentication, and security-related semantics of this
operation are given in [AuthMeth].
- The Bind Request is defined as follows:
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+ 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 for the LDAP exchange. This document describes version
- 3 of the protocol. There is no version negotiation. The client
- sets this field to the version it desires. If the server does not
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- support the specified version, it MUST respond with protocolError
- in the resultCode field of the BindResponse.
+ to be used at the LDAP message layer. This document describes
+ version 3 of the protocol. There is no version negotiation. The
+ client sets this field to the version it desires. If the server
+ does not support the specified version, it MUST respond with 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
- 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 decision of which access an operation has to the
- directory. Among other things, the process of authorization takes as
- input authentication information obtained during the bind operation
- and/or other acts of authentication (such as lower layer security
- services).
-
+
+
+
+
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4.2.1. Processing of the Bind Request
Before processing a BindRequest, all uncompleted operations MUST
either complete or be abandoned. The server may either wait for the
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
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
- LDAP exchange, it may close the connection, reopen it and begin again
- by first sending a PDU with a Bind Request. This will aid in
- interoperating with servers implementing other versions of LDAP.
+ 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.
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- Clients may send multiple Bind Requests on an LDAP exchange to change
- the authentication and/or security associations or to complete a
- multi-stage bind process. Authentication from earlier binds is
- 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 ([AuthMeth] Section
- 8.2). Clients MUST NOT invoke operations between two Bind Requests
- made as part of a multi-stage bind.
+ 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.
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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+\f
+ 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 closing and re-
- establishing the 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 close the connection.
+ 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
this field SHALL NOT be included in the BindResponse.
-
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- Lightweight Directory Access Protocol Version 3
-
4.3. Unbind Operation
- The function of the Unbind Operation is to terminate an LDAP exchange
- and close the connection. The Unbind operation is not the antithesis
- of the Bind operation as the name implies. The naming of these
- operations is historical. The Unbind operation should be thought of
- as the "quit" operation.
+ The 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
- exchange terminated, MUST cease transmission of messages to the other
- peer, and MUST close the connection. Uncompleted operations are
- handled as specified in Section 5.1.
+ 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 LDAP exchange or connection 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.
+ 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
This notification may be used by the server to advise the client that
- the server is about to close the connection due to an error
- condition. This notification is intended to assist clients in
- distinguishing between an error condition and a transient network
-
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- Lightweight Directory Access Protocol Version 3
-
- failure. Note that this notification is not a response to an unbind
- requested by the client. Uncompleted operations are handled as
- specified in Section 5.1.
+ 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 responseValue field
is absent, and the resultCode is used to indicate the reason for the
- disconnection.
+ 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.
- Upon transmission of the Notice of Disconnection, the server is to
- consider the LDAP exchange 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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+\f
+ Lightweight Directory Access Protocol Version 3
+
SearchRequest ::= [APPLICATION 3] SEQUENCE {
baseObject LDAPDN,
scope ENUMERATED {
baseObject (0),
singleLevel (1),
- wholeSubtree (2) },
+ wholeSubtree (2),
+ ... },
derefAliases ENUMERATED {
neverDerefAliases (0),
derefInSearching (1),
AttributeSelection ::= SEQUENCE OF selector LDAPString
-- The LDAPString is constrained to
- -- <attributeSelector> below
+ -- <attributeSelector> in Section 4.5.1.7
Filter ::= CHOICE {
- and [0] SET OF filter Filter,
- or [1] SET OF filter Filter,
+ and [0] SET SIZE (1..MAX) OF filter Filter,
+ or [1] SET SIZE (1..MAX) OF filter Filter,
not [2] Filter,
equalityMatch [3] AttributeValueAssertion,
substrings [4] SubstringFilter,
greaterOrEqual [5] AttributeValueAssertion,
-
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- Lightweight Directory Access Protocol Version 3
-
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:
+
+
+
+
+
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+\f
+ Lightweight Directory Access Protocol Version 3
+
+ 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.
- - 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.
-
- wholeSubtree: the scope is constrained to the entry named by
- the baseObject, and all its subordinates.
+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.
- - 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.
-
+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.
+
+
+
+
+
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+\f
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- 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.
+ 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.
- 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) 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.
+ derefFindingBaseObj: Dereference aliases in locating the base
+ object of the Search, but not when searching subordinates of the
+ base object.
- 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.
-
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+ 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
-
- 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 for the attribute, this filter item should be
- treated as an equalityMatch.
-
- 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
+ - The attribute type does not define the appropriate matching
+ rule.
+
+ - A MatchingRuleId in the extensibleMatch is not recognized by
+ the server or is not valid for the attribute type.
+
+ - The type of filtering requested is not implemented.
+
+ - The assertion value is invalid.
+
+
+
+
+
+
+
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+\f
Lightweight Directory Access Protocol Version 3
- 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.
- Examples include:
-
- - An attribute description in an equalityMatch, substrings,
- greaterOrEqual, lessOrEqual, approxMatch or extensibleMatch
- filter is not recognized by the server.
-
- - The attribute type does not define the appropriate matching
- rule.
-
- - A MatchingRuleId in the extensibleMatch is not recognized by
- the server or is not valid for the attribute type.
+ For example, if a server did not recognize the attribute type
+ shoeSize, a filter of (shoeSize=*) would evaluate to FALSE, and the
+ filters (shoeSize=12), (shoeSize>=12) and (shoeSize<=12) would each
+ evaluate to Undefined.
+
+ Servers MUST NOT return errors if attribute descriptions or matching
+ rule ids are not recognized, assertion values are 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
+
+ The matching rule for equalityMatch filter items is defined by the
+ EQUALITY matching rule for the attribute type.
+
+
+4.5.1.7.2 SearchRequest.filter.substrings
+
+ 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 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.
+
+
+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.
- - The type of filtering requested is not implemented.
+ - 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 assertion value is invalid.
+ 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.
- For example, if a server did not recognize the attribute type
- shoeSize, a filter of (shoeSize=*) would evaluate to FALSE, and
- the filters (shoeSize=12), (shoeSize>=12) and (shoeSize<=12) would
- each evaluate to Undefined.
-
- Servers MUST NOT return errors if attribute descriptions or
- matching rule ids are not recognized, assertion values are
- invalid, or the assertion syntax is not supported. More details of
- filter processing are given in Section 7.8 of [X.511].
- - 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]):
+4.5.1.7 SearchRequest.attributes
- attributeSelector = attributedescription / selectorpecial
+ 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
+
noattrs = %x31.2E.31 ; "1.1"
alluserattrs = %x2A ; asterisk ("*")
-
-
-
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- Lightweight Directory Access Protocol Version 3
-
The <attributedescription> production is defined in Section 2.5 of
[Models].
- There are three special cases which may appear in the attributes
- selection list:
+ 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
+ descriptions), and
- a list containing only "1.1".
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.
-
- 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.
+ 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 messages, zero or more SearchResultReference
- messages, followed by a single searchResultDone message.
+ 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 {
-
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- Lightweight Directory Access Protocol Version 3
-
objectName LDAPDN,
attributes PartialAttributeList }
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
- 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 either a
+ 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
- referral or noSuchObject result code (depending on the server's
- knowledge of the entry named in the baseObject).
-
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.
- 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 the LDAP exchange between a client and
- server. The client must abandon subsequent search operations it
- wishes to individually.
+ 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 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.
+ 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].
- When an LDAP URL is used, the following instructions are followed:
+ SearchResultReference values which are LDAP URLs follow these rules:
- - 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].
+ - 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.
- Some servers (e.g. participating in distributed indexing) may
- provide a different filter in a URL of a SearchResultReference.
+ provide a different filter in the LDAP URL.
- - 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.
+ - 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".
+ of the LDAP URL will be "base".
- It is RECOMMENDED that the <scope> part be present to avoid
- ambiguity.
+ 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
+ - Other aspects of the new Search request may be the same as or
+ different from the Search request which generated the
SearchResultReference.
+
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-
- 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)
-
-
-
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-
- If the contacted server does not hold the base object for the search,
+ 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
+ subtree Search of <DC=Example,DC=ORG> to hosta, the server returns a
SearchResultDone containing a referral.
SearchResultDone (referral) {
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
modification. The values of this field have the following
semantics respectively:
+
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+ 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;
-
-
-
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-
replace: replace all existing values of the modification
attribute with the new values listed, creating the attribute
if it did not already exist. A replace with no value will
been performed if the Modify Response received indicates any sort of
error, and that all requested modifications have been performed if
the Modify Response indicates successful completion of the Modify
- Operation. The result of the modification is indeterminate if the
- Modify Response is not received (e.g. the LDA exchange is terminated
- or the Modify Operation is abandoned).
-
- The Modify Operation cannot be used to remove from an entry any of
- its distinguished values, i.e. those values which form the entry's
- 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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+ 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 {
AttributeList ::= SEQUENCE OF attribute Attribute
Fields of the Add Request are:
-
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-
- entry: the name of the entry to be added. The server SHALL NOT
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 MAY or
- MAY NOT include the RDN attribute in this list. Clients MUST
- include the 'objectClass' attribute, and values of any mandatory
- 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.
+ 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>.
- 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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+ 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
the entry removal requested and return the result in the Delete
Response defined as follows:
-
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- Lightweight Directory Access Protocol Version 3
-
DelResponse ::= [APPLICATION 11] LDAPResult
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 the operation moves the entry
- to a new superior without changing its RDN, the value of the old
- RDN is supplied for this parameter.
- 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.
+ - 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
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
-
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- Lightweight Directory Access Protocol Version 3
-
<DC=Example,DC=NET> entry did not exist, and the <DC=NET> entry did
exist, then the server would return the noSuchObject result code with
the matchedDN field containing <DC=NET>.
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:
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 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.
+ 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.
-
-
-
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-
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
+ 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 exchange. The abandon request itself has its own MessageID.
- This is distinct from the MessageID 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
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.
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
+ 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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+\f
+ 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 extended operation associated with the requestName is not
+ 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 a resultCode of protocolError.
+ 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 5.2, also follow the extensibility rules in
+ according to Section 5.1, also follow the extensibility rules in
Section 4.
+
+
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+\f
+ 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,
that the same OBJECT IDENTIFIER my be used for both the
requestName and responseName),
-
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- Lightweight Directory Access Protocol Version 3
-
- the format of the contents of the requestValue and responseValue
(if any), and
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 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
+ 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
+ solicited (i.e. in the Extended operation or request control
specification that uses them). These specifications include:
- the OBJECT IDENTIFIER (if any) assigned to the responseName,
- - the format of the contents of the responseValue, and
+ - 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.
4.13.1. Usage with LDAP ExtendedRequest and ExtendedResponse
-
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-
A single-request/multiple-response operation may be defined using a
single ExtendedRequest message to solicit zero or more
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.
4.14. StartTLS Operation
- The Start Transport Layer Security (StartTLS) operationÆs purpose is
+ 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
+ defined using the Extended operation mechanism described in Section
4.12.
+
+
+
+
+
+
+
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+\f
+ Lightweight Directory Access Protocol Version 3
+
4.14.1. StartTLS Request
A client requests TLS establishment by transmitting a StartTLS
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 LDAP exchange following
- this request until it receives a StartTLS extended response and, in
- the case of a successful response, 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.
- Sequencing problems (particularly those detailed in Section 3.1.1 of
- [AuthMeth] result in an operationsError being returned in the
- resultCode.
+ 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 the protocolError resultCode as described
- in Section 4.12.
-
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-
+ configuration), it returns with the resultCode set to protocolError
+ as described in Section 4.12.
4.14.2. StartTLS Response
responseName, if present, is also "1.3.6.1.4.1.1466.20037". The
responseValue is absent.
- If the server is willing and able to negotiate TLS, it returns a
- success resultCode. Refer to Section 4 of [AuthMeth] for details.
+ If the 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 server is otherwise unwilling or unable to perform this
operation, the server is to return an appropriate result code
indicating the nature of the problem. For example, if the TLS
- subsystem is not presently available, the server may return indicate
- so by returning the unavailable resultCode.
+ subsystem is not presently available, the server may indicate so by
+ returning with the resultCode set to unavailable.
4.14.3. Removal of the TLS Layer
- Two forms of TLS layer removal -- graceful and abrupt -- are
- provided. These do not involve LDAP PDUs, but are preformed at the
- underlying layers.
-
- If the connection is closed, uncompleted operations are handled as
- specified in Section 5.1.
-
-
-4.14.3.1. Graceful Removal
-
Either the client or server MAY remove the TLS layer and leave the
- LDAP exchange intact by sending and receiving a TLS closure alert.
+ LDAP message layer intact by sending and receiving a TLS closure
+ alert.
The initiating protocol peer sends the TLS closure alert. If it
- wishes to leave the LDAP exchange 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.
+ 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.
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
+ Lightweight Directory Access Protocol Version 3
+
When a protocol peer receives the initial TLS closure alert, it may
- choose to allow the LDAP exchange to remain intact. In this case, it
- MUST immediately transmit a TLS closure alert. Following this, it MAY
- send and receive LDAP PDUs.
+ 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.
- Protocol peers MAY close the connection after sending or receiving a
- TLS closure alert.
+ Protocol peers MAY terminate the LDAP session after sending or
+ 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
-
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-
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.
-4.14.3.2. Abrupt Removal
-
- Either the client or server MAY abruptly remove the TLS layer by
- closing the connection. In this circumstance, a server MAY send the
- client a Notice of Disconnection before closing the connection.
-
-
5. Protocol Encoding, Connection, and Transfer
This protocol is designed to run over connection-oriented, reliable
units), with each octet and each bit being significant.
One underlying service, LDAP over TCP, is defined in Section
- 5.3. This service is generally applicable to applications providing
+ 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 5.3.
+ described in Section 5.2.
This table illustrates the relationship between the different layers
involved in an exchange between two protocol peers:
- +---------------+
- | LDAP exchange |
- +---------------+ > LDAP PDUs
- +---------------+ < data
- | SASL layer |
- +---------------+ > SASL-protected data
- +---------------+ < data
- | TLS layer |
- Application +---------------+ > TLS-protected data
- ------------+---------------+ < data
- Transport | connection |
- +---------------+
+ +----------------------+
+ | LDAP message layer |
+ +----------------------+ > LDAP PDUs
+ +----------------------+ < data
+ | SASL layer |
+ +----------------------+ > SASL-protected data
+ +----------------------+ < data
+ | TLS layer |
+ Application +----------------------+ > TLS-protected data
+ ------------+----------------------+ < data
+ Transport | transport connection |
+ +----------------------+
+
+
+
+
+
+
+
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+\f
+ Lightweight Directory Access Protocol Version 3
+
+
+5.1. Protocol Encoding
-5.2. 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:
- Only the definite form of length encoding is used.
-
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- Lightweight Directory Access Protocol Version 3
-
- OCTET STRING values are encoded in the primitive form only.
- If the value of a BOOLEAN type is true, the encoding of the value
stated.
-5.3. 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 5.2. It
+ 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
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. Installing SASL layers can provide integrity and other
- data security services.
+ 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.
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
-
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- Lightweight Directory Access Protocol Version 3
-
protected (such as by establishing protections at the transport
layer).
Server implementors should plan for the possibility of (protocol or
external) events which alter the information used to establish
security factors (e.g., credentials, authorization identities, access
- controls) during the course of the LDAP exchange, and even during the
+ 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.
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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+\f
+ Lightweight Directory Access Protocol Version 3
+
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. Invalid protocol encodings include: BER
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
It is also based on RFC 3771 by Roger Harrison, and Kurt Zeilenga.
RFC 3771 was an individual submission to the IETF.
-
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- Lightweight Directory Access Protocol Version 3
-
This document is a product of the IETF LDAPBIS Working Group.
Significant contributors of technical review and content include Kurt
Zeilenga, Steven Legg, and Hallvard Furuseth.
Level Security Mechanisms", draft-ietf-ldapbis-authmeth-
xx.txt, (a work in progress).
+
+
+
+Sermersheim Internet-Draft - Expires Aug 2005 Page 42
+\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
[SASL] Melnikov, A., "Simple Authentication and Security Layer",
draft-ietf-sasl-rfc2222bis-xx.txt (a work in progress).
-
-
-
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- Lightweight Directory Access Protocol Version 3
-
[SASLPrep] Zeilenga, K., "Stringprep profile for user names and
passwords", draft-ietf-sasl-saslprep-xx.txt, (a work in
progress).
[TLS] Dierks, T. and C. Allen. "The TLS Protocol Version 1.1",
draft-ietf-tls-rfc2246-bis-xx.txt, a work in progress.
+
+
+Sermersheim Internet-Draft - Expires Aug 2005 Page 43
+\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),
<http://www.unicode.org/unicode/reports/tr17/>, August
2000.
-
-
-
-
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- Lightweight Directory Access Protocol Version 3
-
[PROTOS-LDAP] University of Oulu, "PROTOS Test-Suite: c06-ldapv3"
<http://www.ee.oulu.fi/research/ouspg/protos/testing/c06/l
dapv3/>
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 StartTLS
- (1.3.6.1.4.1.1466.20037) extended operation.
+ (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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+Sermersheim Internet-Draft - Expires Aug 2005 Page 45
+\f
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
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
+ this code is not used with the Compare operation. See
compareFalse (5) and compareTrue (6).
operationsError (1)
protocolError (2)
Indicates the server received data which is not well-formed.
- For bind operation only, this code is also used to indicate
- that the server does not support the requested protocol
- version.
-
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+\f
Lightweight Directory Access Protocol Version 3
- For extended operations only, this code indicates that the
- server does not support (by design or configuration) the
- extended operation associated with the requestName.
+ 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
exceeded before the operation could be completed.
compareFalse (5)
- Indicates that the compare operation has successfully
+ 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
unavailableCriticalExtension (12)
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.
saslBindInProgress (14)
-
-
-
-
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- Lightweight Directory Access Protocol Version 3
-
Indicates the server requires the client to send a new bind
request, with the same SASL mechanism, to continue the
authentication process (see Section 4.2).
not conform to the required syntax or contains attribute
values which do not conform to the syntax of the attribute's
type.
+
+
+Sermersheim Internet-Draft - Expires Aug 2005 Page 48
+\f
+ Lightweight Directory Access Protocol Version 3
+
aliasDereferencingProblem (36)
Indicates that a problem occurred while dereferencing an
alias. Typically an alias was encountered in a situation
where it was not allowed or where access was denied.
-
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- Lightweight Directory Access Protocol Version 3
-
inappropriateAuthentication (48)
Indicates the server requires the client which had attempted
to bind anonymously or without supplying credentials to
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
For example, this code is returned when a client attempts to
modify the structural object class of an entry.
-
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-
affectsMultipleDSAs (71)
Indicates that the operation cannot be performed as it would
-
-
-
-
-
-
-
-
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+Sermersheim Internet-Draft - Expires Aug 2005 Page 50
+\f
Lightweight Directory Access Protocol Version 3
Appendix B - Complete ASN.1 Definition
LDAPDN ::= LDAPString -- Constrained to <distinguishedName>
-- [LDAPDN]
- RelativeLDAPDN ::= LDAPString -- Constrained to <name-component>
+
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+\f
Lightweight Directory Access Protocol Version 3
+ RelativeLDAPDN ::= LDAPString -- Constrained to <name-component>
-- [LDAPDN]
AttributeDescription ::= LDAPString
MatchingRuleId ::= LDAPString
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
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+\f
+ 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
+
+Sermersheim Internet-Draft - Expires Aug 2005 Page 53
+\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),
AttributeSelection ::= SEQUENCE OF selector LDAPString
-- The LDAPString is constrained to
- -- <attributeSelection> in Section 4.5.1
+ -- <attributeSelector> in Section 4.5.1.7
+
+Sermersheim Internet-Draft - Expires Aug 2005 Page 54
+\f
+ Lightweight Directory Access Protocol Version 3
+
Filter ::= CHOICE {
- and [0] SET OF filter Filter,
- or [1] SET OF filter Filter,
+ and [0] SET SIZE (1..MAX) OF filter Filter,
+ or [1] SET SIZE (1..MAX) OF filter Filter,
not [2] Filter,
equalityMatch [3] AttributeValueAssertion,
substrings [4] SubstringFilter,
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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+\f
+ 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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-
responseValue [11] OCTET STRING OPTIONAL }
IntermediateResponse ::= [APPLICATION 25] SEQUENCE {
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
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+Sermersheim Internet-Draft - Expires Aug 2005 Page 56
+\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 RFC 2251:
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.
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+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 and others
+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 4.1.8
+C.1.8 Section 4.1.8 (Attribute)
- Combined the definitions of PartialAttribute and Attribute here,
and defined Attribute in terms of PartialAttribute.
-C.1.9 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.1.10 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.
+ - Removed imperatives which required clients to use URLs in specific
+ ways to progress an operation. These did nothing for
+ interoperability.
-C.1.11 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.
- - 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 and the ordering
- of controls on a message.
-
-
-Sermersheim Internet-Draft - Expires Apr 2005 Page 55
+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 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
controls).
-C.1.12 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.1.13 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
+ - 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.
+ Bind in relationship to other operations.
-C.1.14 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
+ regarding certain errors used in conjunction with the Bind
operation.
- - Prohibited the server from specifying serverSaslCreds when not
- appropriate.
-
+
-Sermersheim Internet-Draft - Expires Apr 2005 Page 56
+Sermersheim Internet-Draft - Expires Aug 2005 Page 59
+\f
Lightweight Directory Access Protocol Version 3
+ - Prohibited the server from specifying serverSaslCreds when not
+ appropriate.
-C.1.15 Section 4.3
+
+C.1.15 Section 4.3 (Unbind Operation)
- - Required both peers to cease transmission and close the LDAP
- exchange for the unbind operation.
+ - Specified that both peers are to cease transmission and terminate
+ the LDAP session for the Unbind operation.
-C.1.16 Section 4.4
+C.1.16 Section 4.4 (Unsolicited Notification)
- Added instructions for future specifications of Unsolicited
Notifications.
-C.1.17 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
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.1.18 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.1.19 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.1.20 Section 4.5.3.1
+
+
+
+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.1.21 Section 4.6
-
-
-Sermersheim Internet-Draft - Expires Apr 2005 Page 57
- Lightweight Directory Access Protocol Version 3
-
- - Removed restriction that required an EQUALITY matching rule in
- order to perform value delete modifications. It is sufficiently
- documented that in absence of an equality matching rule, octet
- 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.1.22 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.1.23 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.1.24 Section 4.10
+C.1.24 Section 4.10 (Compare Operation)
- - Clarified that compareFalse means that the compare took place and
+ - 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
+ - Required servers to not dereference aliases for Compare. This was
added for consistency with other operations and to help ensure
data consistency.
-C.1.25 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.
+
+Sermersheim Internet-Draft - Expires Aug 2005 Page 61
+\f
+ Lightweight Directory Access Protocol Version 3
+
-C.1.26 Section 4.12
+C.1.26 Section 4.12 (Extended Operation)
- - Specified how values of extended operations defined in terms of
+ - 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.
-
-Sermersheim Internet-Draft - Expires Apr 2005 Page 58
- Lightweight Directory Access Protocol Version 3
-
-C.1.27 Section 5.2
+C.1.27 Section 5.2 (Transfer Protocols)
- Moved referral-specific instructions into referral-related
sections.
-C.1.28 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.1.29 Appendix A
+C.1.29 Appendix A (Complete ASN.1 Definition)
- Added "EXTENSIBILITY IMPLIED" to ASN.1 definition.
- Removed AttributeType. It is not used.
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.
+
+Sermersheim Internet-Draft - Expires Aug 2005 Page 62
+\f
+ Lightweight Directory Access Protocol Version 3
+
-C.2.1 Section 4.13.3.1
+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 RFC 3771:
-
-Sermersheim Internet-Draft - Expires Apr 2005 Page 59
- Lightweight Directory Access Protocol Version 3
-
- - In general, all technical language was transferred in whole.
- Supporting and background language seen as redundant due to its
- 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.
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-Sermersheim Internet-Draft - Expires Apr 2005 Page 60
+Sermersheim Internet-Draft - Expires Aug 2005 Page 63
+\f
Lightweight Directory Access Protocol Version 3
-
-Sermersheim Internet-Draft - Expires Apr 2005 Page 61
\ No newline at end of file
+Sermersheim Internet-Draft - Expires Aug 2005 Page 64
+\f
\ No newline at end of file
-
Internet-Draft Kurt D. Zeilenga
Intended Category: Standard Track OpenLDAP Foundation
-Expires in six months 15 February 2004
+Expires in six months 9 February 2005
LDAP: Internationalized String Preparation
- <draft-ietf-ldapbis-strprep-03.txt>
+ <draft-ietf-ldapbis-strprep-05.txt>
-Status of this Memo
- This document is an Internet-Draft and is in full conformance with all
- provisions of Section 10 of RFC2026.
+Status of this Memo
+ This document is intended to be published as a Standard Track RFC.
Distribution of this memo is unlimited. Technical discussion of this
document will take place on the IETF LDAP Revision Working Group
mailing list <ietf-ldapbis@openldap.org>. Please send editorial
- comments directly to the author <Kurt@OpenLDAP.org>.
+ comments directly to the editor <Kurt@OpenLDAP.org>.
+
+ By submitting this Internet-Draft, I accept the provisions of Section
+ 4 of RFC 3667. By submitting this Internet-Draft, I certify that any
+ applicable patent or other IPR claims of which I am aware have been
+ disclosed, or will be disclosed, and any of which I become aware will
+ be disclosed, in accordance with RFC 3668.
Internet-Drafts are working documents of the Internet Engineering Task
- Force (IETF), its areas, and its working groups. Note that other
+ Force (IETF), its areas, and its working groups. Note that other
groups may also distribute working documents as Internet-Drafts.
+
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
- time. It is inappropriate to use Internet-Drafts as reference
- material or to cite them other than as ``work in progress.''
+ time. It is inappropriate to use Internet-Drafts as reference material
+ or to cite them other than as "work in progress."
The list of current Internet-Drafts can be accessed at
- <http://www.ietf.org/ietf/1id-abstracts.txt>. The list of
- Internet-Draft Shadow Directories can be accessed at
- <http://www.ietf.org/shadow.html>.
+ http://www.ietf.org/1id-abstracts.html
+
+ The list of Internet-Draft Shadow Directories can be accessed at
+ http://www.ietf.org/shadow.html
- Copyright (C) The Internet Society (2004). All Rights Reserved.
+
+ Copyright (C) The Internet Society (2005). All Rights Reserved.
Please see the Full Copyright section near the end of this document
for more information.
+
+
+
+
+Zeilenga LDAPprep [Page 1]
+\f
+Internet-Draft draft-ietf-ldapbis-strprep-05 9 February 2005
+
+
Abstract
The previous Lightweight Directory Access Protocol (LDAP) technical
algorithms for character-based matching rules defined for use in LDAP.
-
-
-
-Zeilenga LDAPprep [Page 1]
-\f
-Internet-Draft draft-ietf-ldapbis-strprep-03 15 February 2004
-
-
-Conventions
+Conventions and Terms
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
Information on the Unicode character encoding model can be found in
[CharModel].
+ The term "combining mark", as used in this specification, refers to
+ any Unicode [Unicode] code point which has a mark property (Mn, Mc,
+ Me). Appendix A provides a complete list of combining marks.
+
1. Introduction
Undefined - it cannot be determined whether the attribute contains
a matching value or not.
+
+
+Zeilenga LDAPprep [Page 2]
+\f
+Internet-Draft draft-ietf-ldapbis-strprep-05 9 February 2005
+
+
For instance, the caseIgnoreMatch matching rule may be used to compare
whether the commonName attribute contains a particular value without
regard for case and insignificant spaces.
commonly used in the Directory. These specifications are inadequate
for strings composed of Unicode [Unicode] characters.
-
-
-
-Zeilenga LDAPprep [Page 2]
-\f
-Internet-Draft draft-ietf-ldapbis-strprep-03 15 February 2004
-
-
The caseIgnoreMatch matching rule [X.520], for example, is simply
defined as being a case insensitive comparison where insignificant
spaces are ignored. For printableString, there is only one space
a) prior to applying the Unicode string preparation steps outlined in
"stringprep", the string is transcoded to Unicode;
+
+
+
+Zeilenga LDAPprep [Page 3]
+\f
+Internet-Draft draft-ietf-ldapbis-strprep-05 9 February 2005
+
+
b) after applying the Unicode string preparation steps outlined in
- "stringprep", characters insignificant to the matching rules are
- removed.
+ "stringprep", the string is modified to appropriately handle
+ characters insignificant to the matching rule.
Hence, preparation of character strings for X.500 matching involves
the following steps:
3) Normalize
4) Prohibit
5) Check Bidi (Bidirectional)
-
-
-
-Zeilenga LDAPprep [Page 3]
-\f
-Internet-Draft draft-ietf-ldapbis-strprep-03 15 February 2004
-
-
- 6) Insignificant Character Removal
+ 6) Insignificant Character Handling
These steps are described in Section 2.
2) Map
3) Normalize
4) Prohibit
- 5) Check bidi
- 6) Insignificant Character Removal
- Failure in any step causes the assertion to evaluate to Undefined.
- This process is intended to act upon non-empty character strings. If
- the string to prepare is empty, this process is not applied and the
- assertion is evaluated to Undefined.
-
- The character repertoire of this process is Unicode 3.2 [Unicode].
+Zeilenga LDAPprep [Page 4]
+\f
+Internet-Draft draft-ietf-ldapbis-strprep-05 9 February 2005
+ 5) Check bidi
+ 6) Insignificant Character Handling
+ Failure in any step causes the assertion to evaluate to Undefined.
-Zeilenga LDAPprep [Page 4]
-\f
-Internet-Draft draft-ietf-ldapbis-strprep-03 15 February 2004
+ The character repertoire of this process is Unicode 3.2 [Unicode].
2.1. Transcode
Each non-Unicode string value is transcoded to Unicode.
- TeletexString [X.680][T.61] values are transcoded to Unicode as
- described in Appendix A.
-
PrintableString [X.680] value are transcoded directly to Unicode.
UniversalString, UTF8String, and bmpString [X.680] values need not be
transcoded as they are Unicode-based strings (in the case of
bmpString, a subset of Unicode).
+ TeletexString [X.680] values are transcoded to Unicode. As there is
+ no standard for mapping TelexString values to Unicode, the mapping is
+ left a local matter.
+
+ For these and other reasons, use of TeletexString is NOT RECOMMENDED.
+
The output is the transcoded string.
SOFT HYPHEN (U+00AD) and MONGOLIAN TODO SOFT HYPHEN (U+1806) code
points are mapped to nothing. COMBINING GRAPHEME JOINER (U+034F) and
- VARIATION SELECTORs (U+180B-180D,FF00-FE0F) code points are also
+ VARIATION SELECTORs (U+180B-180D, FF00-FE0F) code points are also
mapped to nothing. The OBJECT REPLACEMENT CHARACTER (U+FFFC) is
mapped to nothing.
TABULATION (U+000B), FORM FEED (FF) (U+000C), CARRIAGE RETURN (CR)
(U+000D), and NEXT LINE (NEL) (U+0085) are mapped to SPACE (U+0020).
- All other control code points (e.g., Cc) or code points with a control
- function (e.g., Cf) are mapped to nothing.
+ All other control code (e.g., Cc) points or code points with a control
+ function (e.g., Cf) are mapped to nothing. The following is a
+ complete list of these code points: U+0000-0008, 000E-001F, 007F-0084,
+ 0086-009F, 06DD, 070F, 180E, 200C-200F, 202A-202E, 2060-2063,
+ 206A-206F, FEFF, FFF9-FFFB, 1D173-1D17A, E0001, E0020-E007F.
ZERO WIDTH SPACE (U+200B) is mapped to nothing. All other code points
with Separator (space, line, or paragraph) property (e.g, Zs, Zl, or
- Zp) are mapped to SPACE (U+0020).
+ Zp) are mapped to SPACE (U+0020). The following is a complete list of
- Appendix B provides a table detailing the above mappings.
+
+
+Zeilenga LDAPprep [Page 5]
+\f
+Internet-Draft draft-ietf-ldapbis-strprep-05 9 February 2005
+
+
+ these code points: U+0020, 00A0, 1680, 2000-200A, 2028-2029, 202F,
+ 205F, 3000.
For case ignore, numeric, and stored prefix string matching rules,
characters are case folded per B.2 of [StringPrep].
string.
-
-Zeilenga LDAPprep [Page 5]
-\f
-Internet-Draft draft-ietf-ldapbis-strprep-03 15 February 2004
-
-
2.4. Prohibit
All Unassigned code points are prohibited. Unassigned code points are
properties or are deprecated are prohibited. These characters are are
listed in Table C.8 of [StringPrep].
- Private Use (U+E000-F8FF, F0000-FFFFD, 100000-10FFFD) code points are
- prohibited.
+ Private Use code points are prohibited. These characters are listed
+ in Table C.3 of [StringPrep].
- All non-character code points (U+FDD0-FDEF, FFFE-FFFF, 1FFFE-1FFFF,
- 2FFFE-2FFFF, 3FFFE-3FFFF, 4FFFE-4FFFF, 5FFFE-5FFFF, 6FFFE-6FFFF,
- 7FFFE-7FFFF, 8FFFE-8FFFF, 9FFFE-9FFFF, AFFFE-AFFFF, BFFFE-BFFFF,
- CFFFE-CFFFF, DFFFE-DFFFF, EFFFE-EFFFF, FFFFE-FFFFF, 10FFFE-10FFFF) are
- prohibited.
+ All non-character code points are prohibited. These code points are
+ listed in Table C.4 of [StringPrep].
- Surrogate codes (U+D800-DFFFF) are prohibited.
+ Surrogate codes are prohibited. These characters are listed in Table
+ C.5 of [StringPrep].
The REPLACEMENT CHARACTER (U+FFFD) code point is prohibited.
2.5. Check bidi
- This step fails if the input string does not conform to the the
- bidirectional character restrictions detailed in 6 of [Stringprep].
- Otherwise, the output is the input string.
+ Bidirectional characters are ignored.
+
+
+2.6. Insignificant Character Handling
+
+ In this step, the string is modified to ensure proper handling of
-2.6. Insignificant Character Removal
- In this step, characters insignificant to the matching rule are to be
- removed. The characters to be removed differ from matching rule to
- matching rule.
+Zeilenga LDAPprep [Page 6]
+\f
+Internet-Draft draft-ietf-ldapbis-strprep-05 9 February 2005
+
+
+ characters insignificant to the matching rule. This modification
+ differs from matching rule to matching rule.
Section 2.6.1 applies to case ignore and exact string matching.
Section 2.6.2 applies to numericString matching.
Section 2.6.3 applies to telephoneNumber matching.
-2.6.1. Insignificant Space Removal
+2.6.1. Insignificant Space Handling
For the purposes of this section, a space is defined to be the SPACE
(U+0020) code point followed by no combining marks.
-
-
-Zeilenga LDAPprep [Page 6]
-\f
-Internet-Draft draft-ietf-ldapbis-strprep-03 15 February 2004
-
-
NOTE - The previous steps ensure that the string cannot contain any
code points in the separator class, other than SPACE (U+0020).
- If the input string consists entirely of spaces or is empty, the
- output is a string consisting of exactly one space (e.g. " ").
+ If the input string contains at least one non-space character, then
+ the string is modified such that the string starts with exactly one
+ space character, ends with exactly one SPACE character, and that any
+ inner (non-empty) sequence of space characters is replaced with
+ exactly two SPACE characters. For instance, the input strings
+ "foo<SPACE>bar<SPACE><SPACE>", results in the output
+ "<SPACE>foo<SPACE><SPACE>bar<SPACE>".
- Otherwise, the following spaces are removed:
- - leading spaces (i.e. those preceding the first character that is
- not a space);
- - trailing spaces (i.e. those following the last character that is
- not a space);
- - multiple consecutive spaces (these are taken as equivalent to a
- single space character).
+ Otherwise, if the string being prepared is an initial, any, or final
+ substring, then the output string is exactly one SPACE character, else
+ the output string is exactly two SPACEs.
- For example, removal of spaces from the Form KC string:
- "<SPACE><SPACE>foo<SPACE><SPACE>bar<SPACE><SPACE>"
- would result in the output string:
- "foo<SPACE>bar"
- and the Form KC string:
- "<SPACE><SPACE><SPACE>"
- would result in the output string:
- "<SPACE>".
+ Appendix B discusses the rationale for the behavior.
-2.6.2. numericString Insignificant Character Removal
+2.6.2. numericString Insignificant Character Handling
For the purposes of this section, a space is defined to be the SPACE
(U+0020) code point followed by no combining marks.
- All spaces are regarded as not significant. If the input string
- consists entirely of spaces or is empty, the output is a string
- consisting of exactly one space (e.g. " "). Otherwise, all spaces are
- to be removed.
+ All spaces are regarded as insignificant and are to be removed.
For example, removal of spaces from the Form KC string:
"<SPACE><SPACE>123<SPACE><SPACE>456<SPACE><SPACE>"
and the Form KC string:
"<SPACE><SPACE><SPACE>"
would result in the output string:
- "<SPACE>".
+ "" (an empty string).
-2.6.3. telephoneNumber Insignificant Character Removal
-
- For the purposes of this section, a hyphen is defined to be
- HYPHEN-MINUS (U+002D), ARMENIAN HYPHEN (U+058A), HYPHEN (U+2010),
Zeilenga LDAPprep [Page 7]
\f
-Internet-Draft draft-ietf-ldapbis-strprep-03 15 February 2004
+Internet-Draft draft-ietf-ldapbis-strprep-05 9 February 2005
+
+2.6.3. telephoneNumber Insignificant Character Handling
+ For the purposes of this section, a hyphen is defined to be
+ HYPHEN-MINUS (U+002D), ARMENIAN HYPHEN (U+058A), HYPHEN (U+2010),
NON-BREAKING HYPHEN (U+2011), MINUS SIGN (U+2212), SMALL HYPHEN-MINUS
(U+FE63), or FULLWIDTH HYPHEN-MINUS (U+FF0D) code point followed by no
combining marks and a space is defined to be the SPACE (U+0020) code
point followed by no combining marks.
- All hyphens and spaces are considered insignificant. If the string
- contains only spaces and hyphens or is empty, then the output is a
- string consisting of one space. Otherwise, all hyphens and spaces are
+ All hyphens and spaces are considered insignificant and are to be
removed.
For example, removal of hyphens and spaces from the Form KC string:
"123456"
and the Form KC string:
"<HYPHEN><HYPHEN><HYPHEN>"
- would result in the output string:
- "<SPACE>".
+ would result in the (empty) output string:
+ "".
3. Security Considerations
here.
-4. Contributors
-
- Appendix A and B of this document were authored by Howard Chu
- <hyc@symas.com> of Symas Corporation (based upon information provided
- in RFC 1345).
-
-
-5. Acknowledgments
+4. Acknowledgments
The approach used in this document is based upon design principles and
algorithms described in "Preparation of Internationalized Strings
Group.
-6. Author's Address
+5. Author's Address
+
+ Kurt D. Zeilenga
+ OpenLDAP Foundation
+
+ Email: Kurt@OpenLDAP.org
Zeilenga LDAPprep [Page 8]
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+Internet-Draft draft-ietf-ldapbis-strprep-05 9 February 2005
- Kurt D. Zeilenga
- OpenLDAP Foundation
-
- Email: Kurt@OpenLDAP.org
+6. References
+ [[Note to the RFC Editor: please replace the citation tags used in
+ referencing Internet-Drafts with tags of the form RFCnnnn where
+ possible.]]
-7. References
-7.1. Normative References
+6.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14 (also RFC 2119), March 1997.
Syntax Notation One (ASN.1) - Specification of Basic
Notation", X.680(1997) (also ISO/IEC 8824-1:1998).
- [T.61] CCITT (now ITU), "Character Repertoire and Coded
- Character Sets for the International Teletex Service",
- T.61, 1988.
-7.2. Informative References
+6.2. Informative References
+ [X.500] International Telecommunication Union -
+ Telecommunication Standardization Sector, "The Directory
+ -- Overview of concepts, models and services,"
+ X.500(1993) (also ISO/IEC 9594-1:1994).
Zeilenga LDAPprep [Page 9]
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+Internet-Draft draft-ietf-ldapbis-strprep-05 9 February 2005
- [X.500] International Telecommunication Union -
- Telecommunication Standardization Sector, "The Directory
- -- Overview of concepts, models and services,"
- X.500(1993) (also ISO/IEC 9594-1:1994).
-
[X.501] International Telecommunication Union -
Telecommunication Standardization Sector, "The Directory
-- Models," X.501(1993) (also ISO/IEC 9594-2:1994).
RFC 1345, June 1992.
-Appendix A. Teletex (T.61) to Unicode
+Appendix A. Combining Marks
+
+ This appendix is normative.
+
+ 0300-034F 0360-036F 0483-0486 0488-0489 0591-05A1 05A3-05B9 05BB-05BC
+ 05BF 05C1-05C2 05C4 064B-0655 0670 06D6-06DC 06DE-06E4 06E7-06E8
+ 06EA-06ED 0711 0730-074A 07A6-07B0 0901-0903 093C 093E-094F 0951-0954
+ 0962-0963 0981-0983 09BC 09BE-09C4 09C7-09C8 09CB-09CD 09D7 09E2-09E3
+ 0A02 0A3C 0A3E-0A42 0A47-0A48 0A4B-0A4D 0A70-0A71 0A81-0A83 0ABC
+ 0ABE-0AC5 0AC7-0AC9 0ACB-0ACD 0B01-0B03 0B3C 0B3E-0B43 0B47-0B48
+ 0B4B-0B4D 0B56-0B57 0B82 0BBE-0BC2 0BC6-0BC8 0BCA-0BCD 0BD7 0C01-0C03
+ 0C3E-0C44 0C46-0C48 0C4A-0C4D 0C55-0C56 0C82-0C83 0CBE-0CC4 0CC6-0CC8
+ 0CCA-0CCD 0CD5-0CD6 0D02-0D03 0D3E-0D43 0D46-0D48 0D4A-0D4D 0D57
+ 0D82-0D83 0DCA 0DCF-0DD4 0DD6 0DD8-0DDF 0DF2-0DF3 0E31 0E34-0E3A
+ 0E47-0E4E 0EB1 0EB4-0EB9 0EBB-0EBC 0EC8-0ECD 0F18-0F19 0F35 0F37 0F39
+ 0F3E-0F3F 0F71-0F84 0F86-0F87 0F90-0F97 0F99-0FBC 0FC6 102C-1032
+ 1036-1039 1056-1059 1712-1714 1732-1734 1752-1753 1772-1773 17B4-17D3
+ 180B-180D 18A9 20D0-20EA 302A-302F 3099-309A FB1E FE00-FE0F FE20-FE23
+ 1D165-1D169 1D16D-1D172 1D17B-1D182 1D185-1D18B 1D1AA-1D1AD
- This appendix defines an algorithm for transcoding [T.61] characters
- to [Unicode] characters for use in string preparation for LDAP
- matching rules. This appendix is normative.
- The transcoding algorithm is derived from the T.61-8bit definition
- provided in [RFC1345]. With a few exceptions, the T.61 character
- codes from x00 to x7f are equivalent to the corresponding [Unicode]
- code points, and their values are left unchanged by this algorithm.
- E.g. the T.61 code x20 is identical to (U+0020). The exceptions are
- for these T.61 codes that are undefined: x23, x24, x5c, x5e, x60, x7b,
- x7d, and x7e.
- The codes from x80 to x9f are also equivalent to the corresponding
- Unicode code points. This is specified for completeness only, as
- these codes are control characters, and will be mapped to nothing in
- the LDAP String Preparation Mapping step.
+Appendix B. Substrings Matching
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-
-
- The remaining T.61 codes are mapped below in Table A.1. Table
- positions marked "??" are undefined.
-
- Input strings containing undefined T.61 codes SHALL produce an
- Undefined matching result. For diagnostic purposes, this algorithm
- does not fail for undefined input codes. Instead, undefined codes in
- the input are mapped to the Unicode REPLACEMENT CHARACTER (U+FFFD).
- As the LDAP String Preparation Prohibit step disallows the REPLACEMENT
- CHARACTER from appearing in its output, this transcoding yields the
- desired effect.
-
- Note: RFC 1345 listed the non-spacing accent codepoints as residing in
- the range starting at (U+E000). In the current Unicode
- standard, the (U+E000) range is reserved for Private Use, and
- the non-spacing accents are in the range starting at (U+0300).
- The tables here use the (U+0300) range for these accents.
-
- | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
- --+------+------+------+------+------+------+------+------+
- a0| 00a0 | 00a1 | 00a2 | 00a3 | 0024 | 00a5 | 0023 | 00a7 |
- a8| 00a8 | ?? | ?? | 00ab | ?? | ?? | ?? | ?? |
- b0| 00b0 | 00b1 | 00b2 | 00b3 | 00d7 | 00b5 | 00b6 | 00b7 |
- b8| 00f7 | ?? | ?? | 00bb | 00bc | 00bd | 00be | 00bf |
- c0| ?? | 0300 | 0301 | 0302 | 0303 | 0304 | 0306 | 0307 |
- c8| 0308 | ?? | 030a | 0327 | 0332 | 030b | 0328 | 030c |
- d0| ?? | ?? | ?? | ?? | ?? | ?? | ?? | ?? |
- d8| ?? | ?? | ?? | ?? | ?? | ?? | ?? | ?? |
- e0| 2126 | 00c6 | 00d0 | 00aa | ?? | 0126 | 0132 | 013f |
- e8| 0141 | 00d8 | 0152 | 00ba | 00de | 0166 | 014a | 0149 |
- f0| 0138 | 00e6 | 0111 | 00f0 | 0127 | 0131 | 0133 | 0140 |
- f8| 0142 | 00f8 | 0153 | 00df | 00fe | 0167 | 014b | ?? |
- --+------+------+------+------+------+------+------+------+
- Table A.1: Mapping of 8-bit T.61 codes to Unicode
-
- T.61 also defines a number of accented characters that are formed by
- combining an accent prefix followed by a base character. These
- prefixes are in the code range xc1 to xcf. If a prefix character
- appears at the end of a string, the result is undefined. Otherwise
- these sequences are mapped to Unicode by substituting the
- corresponding non-spacing accent code (as listed in Table A.1) for the
- accent prefix, and exchanging the order so that the base character
- precedes the accent.
-
-
-Appendix B. Additional Teletex (T.61) to Unicode Tables
-
- All of the accented characters in T.61 have a corresponding code point
- in Unicode. For the sake of completeness, the combined character
+Internet-Draft draft-ietf-ldapbis-strprep-05 9 February 2005
+
+
+ In absence of substrings matching, the insignificant space handling
+ for case ignore/exact matching could be simplified. Specifically,
+ the handling could be as require all sequences of one or more spaces
+ be replaced with one space and, if string contains non-space
+ characters, removal of all all leading spaces and trailing spaces.
+
+ In the presence of substrings matching, this simplified space handling
+ this simplified space handling would lead to unexpected and
+ undesirable matching behavior. For instance:
+ 1) (CN=foo\20*\20bar) would match the CN value "foobar" but not
+ "foo<SPACE>bar" nor "foo<SPACE><SPACE>bar";
+ 2) (CN=*\20foobar\20*) would match "foobar", but (CN=*\20*foobar*\20*)
+ would not;
+ 3) (CN=foo\20*\20bar) would match "foo<SPACE>X<SPACE>bar" but not
+ "foo<SPACE><SPACE>bar".
+
+ The first case illustrates that this simplified space handling would
+ cause leading and trailing spaces in substrings of the string to be
+ regarded as insignificant. However, only leading and trailing (as
+ well as multiple consecutive spaces) of the string (as a whole) are
+ insignificant.
+
+ The second case illustrates that this simplified space handling would
+ cause sub-partitioning failures. That is, if a prepared any substring
+ matches a partition of the attribute value, then an assertion
+ constructed by subdividing that substring into multiple substrings
+ should also match.
+
+ The third case illustrates that this simplified space handling causes
+ another partitioning failure. Though both the initial or final
+ strings match different portions of "foo<SPACE>X<SPACE>bar" with
+ neither matching the X portion, they don't match a string consisting
+ of the two matched portions less the unmatched X portion.
+
+ In designing an appropriate approach for space handling for substrings
+ matching, one must study key aspects of X.500 case exact/ignore
+ matching. X.520 [X.520] says:
+ The [substrings] rule returns TRUE if there is a partitioning of
+ the attribute value (into portions) such that:
+ - the specified substrings (initial, any, final) match different
+ portions of the value in the order of the strings sequence;
+ - initial, if present, matches the first portion of the value;
+ - final, if present, matches the last portion of the value;
+ - any, if present, matches some arbitrary portion of the value.
+
+ That is, the substrings assertion (CN=foo\20*\20bar) matches the
+ attribute value "foo<SPACE><SPACE>bar" as the value can be partitioned
+ into the portions "foo<SPACE>" and "<SPACE>bar" meeting the above
Zeilenga LDAPprep [Page 11]
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-
-
- codes are presented in the following tables. This is informational
- only; for matching purposes it is sufficient to map the non-spacing
- accent and exchange the order of the character pair as specified in
- Appendix A. This appendix is informative.
-
-
-B.1. Combinations with SPACE
+Internet-Draft draft-ietf-ldapbis-strprep-05 9 February 2005
+
+
+ requirements.
+
+ X.520 also says:
+ [T]he following spaces are regarded as not significant:
+ - leading spaces (i.e. those preceding the first character that is
+ not a space);
+ - trailing spaces (i.e. those following the last character that is
+ not a space);
+ - multiple consecutive spaces (these are taken as equivalent to a
+ single space character).
+
+ This statement applies to the assertion values and attribute values
+ as whole strings, and not individually to substrings of an assertion
+ value. In particular, the statements should be taken to mean that
+ if an assertion value and attribute value match without any
+ consideration to insignificant characters, then that assertion value
+ should also match any attribute value which differs only by inclusion
+ or removal of insignificant characters.
+
+ Hence, the assertion (CN=foo\20*\20bar) matches
+ "foo<SPACE><SPACE><SPACE>bar" and "foo<SPACE>bar" as these values
+ only differ from "foo<SPACE><SPACE>bar" by the inclusion or removal
+ of insignificant spaces.
+
+ Astute readers of this text will also note that there are special
+ cases where the specified space handling does not ignore spaces
+ which could be considered insignificant. For instance, the assertion
+ (CN=\20*\20*\20) does not match "<SPACE><SPACE><SPACE>"
+ (insignificant spaces present in value) nor " " (insignificant
+ spaces not present in value). However, as these cases have no
+ practical application that cannot be met by simple assertions, e.g.
+ (cn=\20), and this minor anomaly can only be fully addressed by a
+ preparation algorithm to be used in conjunction with
+ character-by-character partitioning and matching, the anomaly is
+ considered acceptable.
- Accents may be combined with a <SPACE> to generate the accent by
- itself. For each accent code, the result of combining with <SPACE> is
- listed in Table B.1.
- | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
- --+------+------+------+------+------+------+------+------+
- c0| ?? | 0060 | 00b4 | 005e | 007e | 00af | 02d8 | 02d9 |
- c8| 00a8 | ?? | 02da | 00b8 | ?? | 02dd | 02db | 02c7 |
- --+------+------+------+------+------+------+------+------+
- Table B.1: Mapping of T.61 Accents with <SPACE> to Unicode
+Intellectual Property Rights
-B.2. Combinations for xc1: (Grave accent)
-
- T.61 has predefined characters for combinations with A, E, I, O, and
- U. Unicode also defines combinations for N, W, and Y. All of these
- combinations are present in Table B.2.
-
- | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
- --+------+------+------+------+------+------+------+------+
- 40| ?? | 00c0 | ?? | ?? | ?? | 00c8 | ?? | ?? |
- 48| ?? | 00cc | ?? | ?? | ?? | ?? | 01f8 | 00d2 |
- 50| ?? | ?? | ?? | ?? | ?? | 00d9 | ?? | 1e80 |
- 58| ?? | 1ef2 | ?? | ?? | ?? | ?? | ?? | ?? |
- 60| ?? | 00e0 | ?? | ?? | ?? | 00e8 | ?? | ?? |
- 68| ?? | 00ec | ?? | ?? | ?? | ?? | 01f9 | 00f2 |
- 70| ?? | ?? | ?? | ?? | ?? | 00f9 | ?? | 1e81 |
- 78| ?? | 1ef3 | ?? | ?? | ?? | ?? | ?? | ?? |
- --+------+------+------+------+------+------+------+------+
- Table B.2: Mapping of T.61 Grave Accent Combinations
-
-
-B.3. Combinations for xc2: (Acute accent)
-
- T.61 has predefined characters for combinations with A, E, I, O, U, Y,
- C, L, N, R, S, and Z. Unicode also defines G, K, M, P, and W. All of
- these combinations are present in Table B.3.
-
- | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
- --+------+------+------+------+------+------+------+------+
+ The IETF takes no position regarding the validity or scope of any
+ Intellectual Property Rights or other rights that might be claimed
+ to pertain to the implementation or use of the technology described
+ in this document or the extent to which any license under such
+ rights might or might not be available; nor does it represent that
+ it has made any independent effort to identify any such rights.
+ Information on the procedures with respect to rights in RFC documents
+ can be found in BCP 78 and BCP 79.
Zeilenga LDAPprep [Page 12]
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-
-
- 40| ?? | 00c1 | ?? | 0106 | ?? | 00c9 | ?? | 01f4 |
- 48| ?? | 00cd | ?? | 1e30 | 0139 | 1e3e | 0143 | 00d3 |
- 50| 1e54 | ?? | 0154 | 015a | ?? | 00da | ?? | 1e82 |
- 58| ?? | 00dd | 0179 | ?? | ?? | ?? | ?? | ?? |
- 60| ?? | 00e1 | ?? | 0107 | ?? | 00e9 | ?? | 01f5 |
- 68| ?? | 00ed | ?? | 1e31 | 013a | 1e3f | 0144 | 00f3 |
- 70| 1e55 | ?? | 0155 | 015b | ?? | 00fa | ?? | 1e83 |
- 78| ?? | 00fd | 017a | ?? | ?? | ?? | ?? | ?? |
- --+------+------+------+------+------+------+------+------+
- Table B.3: Mapping of T.61 Acute Accent Combinations
-
-
-B.4. Combinations for xc3: (Circumflex)
-
- T.61 has predefined characters for combinations with A, E, I, O, U, Y,
- C, G, H, J, S, and W. Unicode also defines the combination for Z.
- All of these combinations are present in Table B.4.
-
- | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
- --+------+------+------+------+------+------+------+------+
- 40| ?? | 00c2 | ?? | 0108 | ?? | 00ca | ?? | 011c |
- 48| 0124 | 00ce | 0134 | ?? | ?? | ?? | ?? | 00d4 |
- 50| ?? | ?? | ?? | 015c | ?? | 00db | ?? | 0174 |
- 58| ?? | 0176 | 1e90 | ?? | ?? | ?? | ?? | ?? |
- 60| ?? | 00e2 | ?? | 0109 | ?? | 00ea | ?? | 011d |
- 68| 0125 | 00ee | 0135 | ?? | ?? | ?? | ?? | 00f4 |
- 70| ?? | ?? | ?? | 015d | ?? | 00fb | ?? | 0175 |
- 78| ?? | 0177 | 1e91 | ?? | ?? | ?? | ?? | ?? |
- --+------+------+------+------+------+------+------+------+
- Table B.4: Mapping of T.61 Circumflex Accent Combinations
-
-
-B.5. Combinations for xc4: (Tilde)
-
- T.61 has predefined characters for combinations with A, I, O, U, and
- N. Unicode also defines E, V, and Y. All of these combinations are
- present in Table B.5.
-
- | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
- --+------+------+------+------+------+------+------+------+
- 40| ?? | 00c3 | ?? | ?? | ?? | 1ebc | ?? | ?? |
- 48| ?? | 0128 | ?? | ?? | ?? | ?? | 00d1 | 00d5 |
- 50| ?? | ?? | ?? | ?? | ?? | 0168 | 1e7c | ?? |
- 58| ?? | 1ef8 | ?? | ?? | ?? | ?? | ?? | ?? |
- 60| ?? | 00e3 | ?? | ?? | ?? | 1ebd | ?? | ?? |
- 68| ?? | 0129 | ?? | ?? | ?? | ?? | 00f1 | 00f5 |
- 70| ?? | ?? | ?? | ?? | ?? | 0169 | 1e7d | ?? |
- 78| ?? | 1ef9 | ?? | ?? | ?? | ?? | ?? | ?? |
-
-
-
-Zeilenga LDAPprep [Page 13]
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-
-
- --+------+------+------+------+------+------+------+------+
- Table B.5: Mapping of T.61 Tilde Accent Combinations
-
-
-B.6. Combinations for xc5: (Macron)
-
- T.61 has predefined characters for combinations with A, E, I, O, and
- U. Unicode also defines Y, G, and AE. All of these combinations are
- present in Table B.6.
-
- | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
- --+------+------+------+------+------+------+------+------+
- 40| ?? | 0100 | ?? | ?? | ?? | 0112 | ?? | 1e20 |
- 48| ?? | 012a | ?? | ?? | ?? | ?? | ?? | 014c |
- 50| ?? | ?? | ?? | ?? | ?? | 016a | ?? | ?? |
- 58| ?? | 0232 | ?? | ?? | ?? | ?? | ?? | ?? |
- 60| ?? | 0101 | ?? | ?? | ?? | 0113 | ?? | 1e21 |
- 68| ?? | 012b | ?? | ?? | ?? | ?? | ?? | 014d |
- 70| ?? | ?? | ?? | ?? | ?? | 016b | ?? | ?? |
- 78| ?? | 0233 | ?? | ?? | ?? | ?? | ?? | ?? |
- e0| ?? | 01e2 | ?? | ?? | ?? | ?? | ?? | ?? |
- f0| ?? | 01e3 | ?? | ?? | ?? | ?? | ?? | ?? |
- --+------+------+------+------+------+------+------+------+
- Table B.6: Mapping of T.61 Macron Accent Combinations
-
-
-B.7. Combinations for xc6: (Breve)
-
- T.61 has predefined characters for combinations with A, U, and G.
- Unicode also defines E, I, and O. All of these combinations are
- present in Table B.7.
-
- | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
- --+------+------+------+------+------+------+------+------+
- 40| ?? | 0102 | ?? | ?? | ?? | 0114 | ?? | 011e |
- 48| ?? | 012c | ?? | ?? | ?? | ?? | ?? | 014e |
- 50| ?? | ?? | ?? | ?? | ?? | 016c | ?? | ?? |
- 58| ?? | ?? | ?? | ?? | ?? | ?? | ?? | ?? |
- 60| ?? | 0103 | ?? | ?? | ?? | 0115 | ?? | 011f |
- 68| ?? | 012d | ?? | ?? | ?? | ?? | 00f1 | 014f |
- 70| ?? | ?? | ?? | ?? | ?? | 016d | ?? | ?? |
- 78| ?? | ?? | ?? | ?? | ?? | ?? | ?? | ?? |
- --+------+------+------+------+------+------+------+------+
- Table B.7: Mapping of T.61 Breve Accent Combinations
-
-
-B.8. Combinations for xc7: (Dot Above)
-
-
-
-
-Zeilenga LDAPprep [Page 14]
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-
-
- T.61 has predefined characters for C, E, G, I, and Z. Unicode also
- defines A, O, B, D, F, H, M, N, P, R, S, T, W, X, and Y. All of these
- combinations are present in Table B.8.
-
- | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
- --+------+------+------+------+------+------+------+------+
- 40| ?? | 0226 | 1e02 | 010a | 1e0a | 0116 | 1e1e | 0120 |
- 48| 1e22 | 0130 | ?? | ?? | ?? | 1e40 | 1e44 | 022e |
- 50| 1e56 | ?? | 1e58 | 1e60 | 1e6a | ?? | ?? | 1e86 |
- 58| 1e8a | 1e8e | 017b | ?? | ?? | ?? | ?? | ?? |
- 60| ?? | 0227 | 1e03 | 010b | 1e0b | 0117 | 1e1f | 0121 |
- 68| 1e23 | ?? | ?? | ?? | ?? | 1e41 | 1e45 | 022f |
- 70| 1e57 | ?? | 1e59 | 1e61 | 1e6b | ?? | ?? | 1e87 |
- 78| 1e8b | 1e8f | 017c | ?? | ?? | ?? | ?? | ?? |
- --+------+------+------+------+------+------+------+------+
- Table B.8: Mapping of T.61 Dot Above Accent Combinations
-
-
-B.9. Combinations for xc8: (Diaeresis)
+Internet-Draft draft-ietf-ldapbis-strprep-05 9 February 2005
- T.61 has predefined characters for A, E, I, O, U, and Y. Unicode also
- defines H, W, X, and t. All of these combinations are present in
- Table B.9.
- | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
- --+------+------+------+------+------+------+------+------+
- 40| ?? | 00c4 | ?? | ?? | ?? | 00cb | ?? | ?? |
- 48| 1e26 | 00cf | ?? | ?? | ?? | ?? | ?? | 00d6 |
- 50| ?? | ?? | ?? | ?? | ?? | 00dc | ?? | 1e84 |
- 58| 1e8c | 0178 | ?? | ?? | ?? | ?? | ?? | ?? |
- 60| ?? | 00e4 | ?? | ?? | ?? | 00eb | ?? | ?? |
- 68| 1e27 | 00ef | ?? | ?? | ?? | ?? | ?? | 00f6 |
- 70| ?? | ?? | ?? | ?? | 1e97 | 00fc | ?? | 1e85 |
- 78| 1e8d | 00ff | ?? | ?? | ?? | ?? | ?? | ?? |
- --+------+------+------+------+------+------+------+------+
- Table B.8: Mapping of T.61 Diaeresis Accent Combinations
-
-
-B.10. Combinations for xca: (Ring Above)
-
- T.61 has predefined characters for A, and U. Unicode also defines w
- and y. All of these combinations are present in Table B.10.
-
- | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
- --+------+------+------+------+------+------+------+------+
- 40| ?? | 00c5 | ?? | ?? | ?? | ?? | ?? | ?? |
- 48| ?? | ?? | ?? | ?? | ?? | ?? | ?? | ?? |
- 50| ?? | ?? | ?? | ?? | ?? | 016e | ?? | ?? |
-
-
-
-Zeilenga LDAPprep [Page 15]
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-
-
- 58| ?? | ?? | ?? | ?? | ?? | ?? | ?? | ?? |
- 60| ?? | 00e5 | ?? | ?? | ?? | ?? | ?? | ?? |
- 68| ?? | ?? | ?? | ?? | ?? | ?? | ?? | ?? |
- 70| ?? | ?? | ?? | ?? | ?? | 016f | ?? | 1e98 |
- 78| ?? | 1e99 | ?? | ?? | ?? | ?? | ?? | ?? |
- --+------+------+------+------+------+------+------+------+
- Table B.10: Mapping of T.61 Ring Above Accent Combinations
-
-
-B.11. Combinations for xcb: (Cedilla)
-
- T.61 has predefined characters for C, G, K, L, N, R, S, and T.
- Unicode also defines E, D, and H. All of these combinations are
- present in Table B.11.
-
- | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
- --+------+------+------+------+------+------+------+------+
- 40| ?? | ?? | ?? | 00c7 | 1e10 | 0228 | ?? | 0122 |
- 48| 1e28 | ?? | ?? | 0136 | 013b | ?? | 0145 | ?? |
- 50| ?? | ?? | 0156 | 015e | 0162 | ?? | ?? | ?? |
- 58| ?? | ?? | ?? | ?? | ?? | ?? | ?? | ?? |
- 60| ?? | ?? | ?? | 00e7 | 1e11 | 0229 | ?? | 0123 |
- 68| 1e29 | ?? | ?? | 0137 | 013c | ?? | 0146 | ?? |
- 70| ?? | ?? | 0157 | 015f | 0163 | ?? | ?? | ?? |
- 78| ?? | ?? | ?? | ?? | ?? | ?? | ?? | ?? |
- --+------+------+------+------+------+------+------+------+
- Table B.11: Mapping of T.61 Cedilla Accent Combinations
-
-
-B.12. Combinations for xcd: (Double Acute Accent)
-
- T.61 has predefined characters for O, and U. These combinations are
- present in Table B.12.
-
- | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
- --+------+------+------+------+------+------+------+------+
- 48| ?? | ?? | ?? | ?? | ?? | ?? | ?? | 0150 |
- 50| ?? | ?? | ?? | ?? | ?? | 0170 | ?? | ?? |
- 68| ?? | ?? | ?? | ?? | ?? | ?? | ?? | 0151 |
- 70| ?? | ?? | ?? | ?? | ?? | 0171 | ?? | ?? |
- --+------+------+------+------+------+------+------+------+
- Table B.12: Mapping of T.61 Double Acute Accent Combinations
-
-
-B.13. Combinations for xce: (Ogonek)
-
- T.61 has predefined characters for A, E, I, and U. Unicode also
- defines the combination for O. All of these combinations are present
-
-
-
-Zeilenga LDAPprep [Page 16]
-\f
-Internet-Draft draft-ietf-ldapbis-strprep-03 15 February 2004
-
-
- in Table B.13.
-
- | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
- --+------+------+------+------+------+------+------+------+
- 40| ?? | 0104 | ?? | ?? | ?? | 0118 | ?? | ?? |
- 48| ?? | 012e | ?? | ?? | ?? | ?? | ?? | 01ea |
- 50| ?? | ?? | ?? | ?? | ?? | 0172 | ?? | ?? |
- 58| ?? | ?? | ?? | ?? | ?? | ?? | ?? | ?? |
- 60| ?? | 0105 | ?? | ?? | ?? | 0119 | ?? | ?? |
- 68| ?? | 012f | ?? | ?? | ?? | ?? | ?? | 01eb |
- 70| ?? | ?? | ?? | ?? | ?? | 0173 | ?? | ?? |
- 78| ?? | ?? | ?? | ?? | ?? | ?? | ?? | ?? |
- --+------+------+------+------+------+------+------+------+
- Table B.13: Mapping of T.61 Ogonek Accent Combinations
-
-
-B.14. Combinations for xcf: (Caron)
-
- T.61 has predefined characters for C, D, E, L, N, R, S, T, and Z.
- Unicode also defines A, I, O, U, G, H, j,and K. All of these
- combinations are present in Table B.14.
-
- | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
- --+------+------+------+------+------+------+------+------+
- 40| ?? | 01cd | ?? | 010c | 010e | 011a | ?? | 01e6 |
- 48| 021e | 01cf | ?? | 01e8 | 013d | ?? | 0147 | 01d1 |
- 50| ?? | ?? | 0158 | 0160 | 0164 | 01d3 | ?? | ?? |
- 58| ?? | ?? | 017d | ?? | ?? | ?? | ?? | ?? |
- 60| ?? | 01ce | ?? | 010d | 010f | 011b | ?? | 01e7 |
- 68| 021f | 01d0 | 01f0 | 01e9 | 013e | ?? | 0148 | 01d2 |
- 70| ?? | ?? | 0159 | 0161 | 0165 | 01d4 | ?? | ?? |
- 78| ?? | ?? | 017e | ?? | ?? | ?? | ?? | ?? |
- --+------+------+------+------+------+------+------+------+
- Table B.14: Mapping of T.61 Caron Accent Combinations
-
-
- Appendix B -- Mapping Table
-
- Input Output
- ----- ------
- 0000-0008
- 0009-000D 0020
- 000E-001F
- 007F-009F
- 0085 0020
- 00A0 0020
- 00AD
- 034F
-
-
-
-Zeilenga LDAPprep [Page 17]
-\f
-Internet-Draft draft-ietf-ldapbis-strprep-03 15 February 2004
-
-
- 06DD
- 070F
- 1680 0020
- 1806
- 180B-180E
- 2000-200A 0020
- 200B-200F
- 2028-2029 0020
- 202A-202E
- 202F 0020
- 205F 0020
- 2060-2063
- 206A-206F
- 3000 0020
- FEFF
- FF00-FE0F
- FFF9-FFFC
- 1D173-1D17A
- E0001
- E0020-E007F
-
-
-
-Intellectual Property Rights
-
- The IETF takes no position regarding the validity or scope of any
- intellectual property or other rights that might be claimed to pertain
- to the implementation or use of the technology described in this
- document or the extent to which any license under such rights might or
- might not be available; neither does it represent that it has made any
- effort to identify any such rights. Information on the IETF's
- procedures with respect to rights in standards-track and
- standards-related documentation can be found in BCP-11. Copies of
- claims of rights made available for publication and any assurances of
- licenses to be made available, or the result of an attempt made to
- obtain a general license or permission for the use of such proprietary
- rights by implementors or users of this specification can be obtained
- from the IETF Secretariat.
+ Copies of IPR disclosures made to the IETF Secretariat and any
+ assurances of licenses to be made available, or the result of an
+ attempt made to obtain a general license or permission for the use
+ of such proprietary rights by implementers or users of this
+ specification can be obtained from the IETF on-line IPR repository
+ at http://www.ietf.org/ipr.
The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary
- rights which may cover technology that may be required to practice
- this standard. Please address the information to the IETF Executive
- Director.
+ rights that may cover technology that may be required to implement
+ this standard. Please address the information to the IETF at
+ ietf-ipr@ietf.org.
Full Copyright
+ Copyright (C) The Internet Society (2005). 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.
-
-Zeilenga LDAPprep [Page 18]
-\f
-Internet-Draft draft-ietf-ldapbis-strprep-03 15 February 2004
-
-
- Copyright (C) The Internet Society (2004). All Rights Reserved.
-
- This document and translations of it may be copied and furnished to
- others, and derivative works that comment on or otherwise explain it
- or assist in its implementation may be prepared, copied, published and
- distributed, in whole or in part, without restriction of any kind,
- provided that the above copyright notice and this paragraph are
- included on all such copies and derivative works. However, this
- document itself may not be modified in any way, such as by removing
- the copyright notice or references to the Internet Society or other
- Internet organizations, except as needed for the purpose of
- developing Internet standards in which case the procedures for
- copyrights defined in the Internet Standards process must be followed,
- or as required to translate it into languages other than English.
-
-
+ This document and the information contained herein are provided on an
+ "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE
+ REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE
+ INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR
+ IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF
+ THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
+ WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
-
-
-
-
-
-
-
-
-
-
-
-
-Zeilenga LDAPprep [Page 19]
+Zeilenga LDAPprep [Page 13]
\f
+
--- /dev/null
+Network Working Group J. Sermersheim
+Internet-Draft Novell, Inc
+Expires: April 24, 2005 October 24, 2004
+
+
+
+ Distributed Procedures for LDAP Operations
+ draft-sermersheim-ldap-distproc-01.txt
+
+
+Status of this Memo
+
+
+ This document is an Internet-Draft and is subject to all provisions
+ of section 3 of RFC 3667. By submitting this Internet-Draft, each
+ 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."
+
+
+ The list of current Internet-Drafts can be accessed at
+ http://www.ietf.org/ietf/1id-abstracts.txt.
+
+
+ The list of Internet-Draft Shadow Directories can be accessed at
+ http://www.ietf.org/shadow.html.
+
+
+ This Internet-Draft will expire on April 24, 2005.
+
+
+Copyright Notice
+
+
+ Copyright (C) The Internet Society (2004).
+
+
+Abstract
+
+
+ This document provides the data types and procedures used while
+ servicing Lightweight Directory Application Protocol (LDAP) user
+ operations in order to participate in a distributed directory. In
+ particular, it describes the way in which an LDAP user operation in a
+ distributed directory environment finds its way to the proper DSA(s)
+ for servicing.
+
+
+Discussion Forum
+
+
+
+
+Sermersheim Expires April 24, 2005 [Page 1]
+Internet-Draft Distributed Procedures for LDAP OperationsOctober 2004
+
+
+
+ Technical discussion of this document will take place on the IETF
+ LDAP Extensions mailing list <ldapext@ietf.org>. Please send
+ editorial comments directly to the author.
+
+
+Table of Contents
+
+
+ 1. Distributed Operations Overview . . . . . . . . . . . . . . 3
+ 2. Conventions . . . . . . . . . . . . . . . . . . . . . . . . 4
+ 3. Distributed Operation Data Types . . . . . . . . . . . . . . 5
+ 3.1 ContinuationReference . . . . . . . . . . . . . . . . . . . 5
+ 3.2 ChainedRequest . . . . . . . . . . . . . . . . . . . . . . . 9
+ 3.3 Chained Response . . . . . . . . . . . . . . . . . . . . . . 11
+ 4. Distributed Procedures . . . . . . . . . . . . . . . . . . . 14
+ 4.1 Name resolution . . . . . . . . . . . . . . . . . . . . . . 14
+ 4.2 Operation Evaluation . . . . . . . . . . . . . . . . . . . . 16
+ 4.3 Populating the ContinuationReference . . . . . . . . . . . . 19
+ 4.4 Sending a ChainedRequest . . . . . . . . . . . . . . . . . . 21
+ 4.5 Emulating the Sending of a ChainedRequest . . . . . . . . . 23
+ 4.6 Receiving a ChainedRequest . . . . . . . . . . . . . . . . . 24
+ 4.7 Returning a Chained Response . . . . . . . . . . . . . . . . 25
+ 4.8 Receiving a Chained Response . . . . . . . . . . . . . . . . 26
+ 4.9 Returning a Referral or Intermediate Referral . . . . . . . 27
+ 4.10 Acting on a Referral or Intermediate Referral . . . . . . . 30
+ 4.11 Ensuring non-existence of an entry under an nssr . . . . . . 31
+ 4.12 Mapping a referralURI to an LDAP URI . . . . . . . . . . . . 31
+ 4.13 Using the ManageDsaIT control . . . . . . . . . . . . . . . 32
+ 5. Security Considerations . . . . . . . . . . . . . . . . . . 33
+ 6. Normative References . . . . . . . . . . . . . . . . . . . . 33
+ Author's Address . . . . . . . . . . . . . . . . . . . . . . 34
+ A. IANA Considerations . . . . . . . . . . . . . . . . . . . . 35
+ A.1 LDAP Object Identifier Registrations . . . . . . . . . . . . 35
+ A.2 LDAP Protocol Mechanism Registrations . . . . . . . . . . . 35
+ A.3 LDAP Descriptor Registrations . . . . . . . . . . . . . . . 37
+ A.4 LDAP Result Code Registrations . . . . . . . . . . . . . . . 38
+ Intellectual Property and Copyright Statements . . . . . . . 39
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+Sermersheim Expires April 24, 2005 [Page 2]
+Internet-Draft Distributed Procedures for LDAP OperationsOctober 2004
+
+
+
+1. Distributed Operations Overview
+
+
+ One characteristic of X.500-based directory systems [X500] is that,
+ given a distributed Directory Information Tree (DIT), a user should
+ potentially be able to have any service request satisfied (subject to
+ security, access control, and administrative policies) irrespective
+ of the Directory Service Agent (DSA) to which the request was sent.
+ To accommodate this requirement, it is necessary that any DSA
+ involved in satisfying a particular service request have some
+ knowledge (as specified in {TODO: Link to future Distributed Data
+ Model doc}) of where the requested information is located and either
+ return this knowledge to the requester or attempt to satisfy the
+ request satisfied on the behalf of the requester (the requester may
+ either be a Directory User Agent (DUA) or another DSA).
+
+
+ Two modes of operation distribution are defined to meet these
+ requirements, namely "chaining" and "returning referrals".
+ "Chaining" refers to the attempt by a DSA to satisfy a request by
+ sending one or more chained operations to other DSAs. "Returning
+ referrals", is the act of returning distributed knowledge information
+ to the requester, which may then itself interact with the DSA(s)
+ identified by the distributed knowledge information. It is a goal of
+ this document to provide the same level of service whether the
+ chaining or referral mechanism is used to distribute an operation.
+
+
+ The processing of an operation is talked about in two major phases,
+ namely "name resolution", and "operation evaluation". Name
+ resolution is the act of locating a local DSE held on a DSA given a
+ distinguished name (DN). Operation evaluation is the act of
+ performing the operation after the name resolution phase is complete.
+
+
+ While distributing an operation, a request operation may be
+ decomposed into several sub-operations.
+
+
+ The distributed directory operation procedures described in this
+ document assume the absense of the ManageDsaIT control defined in
+ [RFC3296] and described in Section 4.13.
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+Sermersheim Expires April 24, 2005 [Page 3]
+Internet-Draft Distributed Procedures for LDAP OperationsOctober 2004
+
+
+
+2. Conventions
+
+
+ Imperative keywords defined in [RFC2119] are used in this document,
+ and carry the meanings described there.
+
+
+ All Basic Encoding Rules (BER) [X690] encodings follow the
+ conventions found in Section 5.1 of [RFC2251].
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+Sermersheim Expires April 24, 2005 [Page 4]
+Internet-Draft Distributed Procedures for LDAP OperationsOctober 2004
+
+
+
+3. Distributed Operation Data Types
+
+
+ The data types in this section are used by the chaining and referral
+ distributed operation mechanisms described in Section 4
+
+
+3.1 ContinuationReference
+
+
+ As an operation is being processed by a DSA, it is useful to group
+ the information passed between various procedures as a collection of
+ data. The ContinuationReference data type is introduced for this
+ purpose. This data type is populated and consumed by various
+ procedures discussed in various sections of this document. In
+ general, a ContinuationReference is used when indicating that
+ directory information being acted on is not present locally, but may
+ be present elsewhere.
+
+
+ A ContinuationReference consists of one or more addresses which
+ identify remote DSAs along with other information pertaining both to
+ the distributed knowledge information held on the local DSA as well
+ as information relevant to the operation. This data type is
+ expressed here in Abstract Syntax Notation One (ASN.1) [X680].
+
+
+ ContinuationReference ::= SET {
+ referralURI [0] SET SIZE (1..MAX) OF URI,
+ localReference [2] LDAPDN,
+ referenceType [3] ReferenceType,
+ remainingName [4] RelativeLDAPDN OPTIONAL,
+ searchScope [5] SearchScope OPTIONAL,
+ searchedSubtrees [6] SearchedSubtrees OPTIONAL,
+ failedName [7] LDAPDN OPTIONAL,
+ ... }
+
+
+ <Editor's Note: Planned for addition is a searchCriteria field which
+ is used both for assuring that the remote object is in fact the
+ object originally pointed to (this mechanism provides a security
+ measure), and also to allow moved or renamed remote entries to be
+ found. Typically the search criteria would have a filter value of
+ (entryUUID=<something>)>
+
+
+ URI ::= LDAPString -- limited to characters permitted in URIs
+ [RFC2396].
+
+
+ ReferenceType ::= ENUMERATED {
+ superior (0),
+ subordinate (1),
+ cross (2),
+ nonSpecificSubordinate (3),
+
+
+
+
+
+Sermersheim Expires April 24, 2005 [Page 5]
+Internet-Draft Distributed Procedures for LDAP OperationsOctober 2004
+
+
+
+ suplier (4),
+ master (5),
+ immediateSuperior (6),
+ self (7),
+ ... }
+ SearchScope ::= ENUMERATED {
+ baseObject (0),
+ singleLevel (1),
+ wholeSubtree (2),
+ subordinateSubtree (3),
+ ... }
+
+
+ SearchedSubtrees ::= SET OF RelativeLDAPDN
+
+
+ LDAPDN, RelativeLDAPDN, and LDAPString, are defined in [RFC2251].
+
+
+ The following subsections introduce the fields of the
+ ContinuationReference data type, but do not provide in-depth
+ semantics or instructions on the population and consumption of the
+ fields. These topics are discussed as part of the procedural
+ instructions.
+
+
+3.1.1 ContinuationReference.referralURI
+
+
+ The list of referralURI values is used by the receiver to progress
+ the operation. Each value specifies (at minimum) the protocol and
+ address of one or more remote DSA(s) holding the data sought after.
+ URI values which are placed in ContinuationReference.referralURI must
+ allow for certain elements of data to be conveyed. Section 3.1.1.1
+ describes these data elements. Furthermore, a mapping must exist
+ which relates the parts of a specified URI to these data elements.
+ This document provides such a mapping for the LDAP URL [RFC2255] in
+ Section 4.12.
+
+
+ In some cases, a referralURI will contain data which has a
+ counterpart in the fields of the ContinuationReference (an example is
+ where the referralURI is an LDAP URL, holds a <scope> value, and the
+ ContinuationReference.searchScope field is also present). In these
+ cases, the data held on the referralURI overrides the field in the
+ ContinuationReference. Specific examples of this are highlighted in
+ other sections. Providing a means for these values to exist as
+ fields of the ContinuationReference allows one value to be applied to
+ all values of referralURI (as opposed to populating duplicate data on
+ all referralURI values).
+
+
+ If a referralURI value identifies an LDAP-enabled DSA [RFC3377], the
+ LDAP URL form is used.
+
+
+
+
+
+Sermersheim Expires April 24, 2005 [Page 6]
+Internet-Draft Distributed Procedures for LDAP OperationsOctober 2004
+
+
+
+3.1.1.1 Elements of referralURI Values
+
+
+ The following data elements must be allowed and identified for a
+ specified URI type to be used to convey referral information. Each
+ element is given a name which begins with 'referralURI.' for clarity
+ when referencing the elements conceptually in other parts of this
+ document.
+
+
+ o referralURI.protocolIdentifier. There must be an indication of
+ the protocol to be used to contact the DSA identified by the URI.
+ o referralURI.accessPoint. The URI must identify a DSA in a manner
+ that can be used to contact it using the protocol specified in
+ protocolIdentifier.
+ o referralURI.targetObject. Holds the name to be used as the base
+ DN of the operation being progressed. This field must be allowed
+ by the URI specification, but may be omitted in URI instances for
+ various reasons.
+ o referralURI.localReference. See Section 3.1.2. This field must
+ be allowed by the URI specification, but may be omitted in URI
+ instances for various reasons.
+ o referralURI.searchScope. See Section 3.1.5. This field must be
+ allowed by the URI specification, but may be omitted in URI
+ instances for various reasons.
+ o referralURI.searchedSubtrees. See Section 3.1.6. This field must
+ be allowed by the URI specification, but may be omitted in URI
+ instances for various reasons.
+ o referralURI.failedName. See Section 3.1.7. This field must be
+ allowed by the URI specification, but may be omitted in URI
+ instances for various reasons.
+
+
+3.1.2 ContinuationReference.localReference
+
+
+ This names the DSE which was found to hold distributed knowledge
+ information, and thus which caused the ContinuationReference to be
+ formed. This field is primarily used to help convey the new target
+ object name, but may also be used for purposes referential integrity
+ (not discussed here). In the event that the root object holds the
+ distributed knowledge information, this field is present and is
+ populated with an empty DN.
+
+
+3.1.3 ContinuationReference.referenceType
+
+
+ Indicates the DSE Type of the ContinuationReference.localReference.
+ This field may be used to determine how to progress an operations
+ (i.e. if the value is nonSpecificSubordinate, a search continuation
+ will exclude the ContinuationReference.referenceType).
+
+
+
+
+
+
+Sermersheim Expires April 24, 2005 [Page 7]
+Internet-Draft Distributed Procedures for LDAP OperationsOctober 2004
+
+
+
+3.1.4 ContinuationReference.remainingName
+
+
+ In certain scenarios, the localReference does not completely name the
+ DSE to be used as the new target object name. In these cases,
+ remainingName is populated with the RDNSequence relative to the
+ localReference of the target object name being resolved. Some
+ examples of these scenarios include (but are not restricted to):
+
+
+ o During name resolution, the name is not fully resolved, but a DSE
+ holding distributed knowledge information is found, causing a
+ ContinuationReference to be generated.
+ o While searching, an alias is dereferenced. The aliasedObjectName
+ points to a DSE of type glue which is subordinate to a DSE holding
+ distributed knowledge information.
+
+
+3.1.5 ContinuationReference.searchScope
+
+
+ Under certain circumstances, when progressing a search operation, a
+ search scope different than that of the original search request must
+ be used. This field facilitates the conveyance of the proper search
+ scope to be used when progressing the distributed operation.
+
+
+ The scope of subordinateSubtree has been added to the values allowed
+ by the LDAP SearchRequest.scope field. This scope includes the
+ subtree of entries below the base DN, but does not include the base
+ DN itself. This is used here when progressing distributed search
+ operations caused by the existence of a DSE of type nssr.
+
+
+ If a referralURI.searchScope is present, it overrides this field
+ while that referralURI is being operated upon.
+
+
+3.1.6 ContinuationReference.searchedSubtrees
+
+
+ For ContinuationReferences generated while processing a search
+ operation with a scope of wholeSubtree, each value of this field
+ indicates that a particular subtree below the target object has
+ already been searched. Consumers of this data use it to cause the
+ progression of the search operation to exclude these subtrees as a
+ mechanism to avoid receiving duplicate entries.
+
+
+ If a referralURI.searchedSubtrees is present, it overrides this field
+ while that referralURI is being operated upon.
+
+
+3.1.7 ContinuationReference.failedName
+
+
+ When an operation requires that multiple names be resolved (as is the
+ case with the ModifyDN operation), this field is used to specify
+ which name was found to be non-local.
+
+
+
+
+Sermersheim Expires April 24, 2005 [Page 8]
+Internet-Draft Distributed Procedures for LDAP OperationsOctober 2004
+
+
+
+ If a referralURI.failedName is present, it overrides this field while
+ that referralURI is being operated upon.
+
+
+3.2 ChainedRequest
+
+
+ The Chained Request is sent as an LDAP extended operation. The
+ requestName is IANA-ASSIGNED-OID.1. The requestValue is the BER
+ encoding of the following ChainedRequestValue ASN.1 definition:
+
+
+ ChainedRequestValue ::= SEQUENCE {
+
+
+ chainingArguments ChainingArguments,
+ operationRequest OperationRequest }
+
+
+ ChainingArguments ::= SEQUENCE {
+
+
+ targetObject [0] LDAPDN OPTIONAL,
+ referenceType [1] ReferenceType,
+ traceInformation [2] ChainingTraceInformation,
+ searchScope [3] SearchScope OPTIONAL,
+ searchedSubtrees [4] SearchedSubtrees OPTIONAL}
+
+
+ ChainingTraceInformation ::= SET OF LDAPURL
+
+
+ OperationRequest ::= SEQUENCE {
+
+
+ Request ::= CHOICE {
+
+
+ bindRequest BindRequest,
+ searchRequest SearchRequest,
+ modifyRequest ModifyRequest,
+ addRequest AddRequest,
+ delRequest DelRequest,
+ modDNRequest ModifyDNRequest,
+ compareRequest CompareRequest,
+ extendedReq ExtendedRequest,
+ ... },
+ controls [0] Controls COPTIONAL }
+
+
+ BindRequest, SearchRequest, ModifyRequest, AddRequest, DelRequest,
+ ModifyDNRequest, CompareRequest, ExtendedRequest and Controls are
+ defined in [RFC2251].
+
+
+3.2.1 ChainedRequestValue.chainingArguments
+
+
+ In general, these fields assist in refining the original operation as
+ it is to be executed on the receiving DSA.
+
+
+
+
+
+Sermersheim Expires April 24, 2005 [Page 9]
+Internet-Draft Distributed Procedures for LDAP OperationsOctober 2004
+
+
+
+3.2.1.1 ChainedRequestValue.chainingArguments.targetObject
+
+
+ This field contains the new target (or base) DN for the operation.
+
+
+ The sending DSA populates this under different scenarios including
+ the case where an alias has been dereferenced while resolving the DN,
+ and also the case where a referral carries a target name different
+ from the reference object that caused the referral.
+
+
+ This field can be omitted only if it would be the the same value as
+ the object or base object parameter in the
+ ChainedRequestValue.operationRequest, in which case its implied value
+ is that value.
+
+
+ The receiving DSA examines this field and (if present) uses it rather
+ than the base DN held in the ChainedRequestValue.operationRequest.
+
+
+3.2.1.2 ChainedRequestValue.chainingArguments.referenceType
+
+
+ See Section 3.1.3.
+
+
+ If the receiver encounters a value of nonSpecificSubordinate in this
+ field, it indicates that the operation is being chained due to DSE of
+ type nssr. In this case, the receiver allows (and expects) the base
+ DN to name the immediate superior of a context prefix.
+
+
+3.2.1.3 ChainedRequestValue.chainingArguments.traceInformation
+
+
+ This contains a set of URIs. Each value represents the address of a
+ DSA and DN that has already been contacted while attempting to
+ service the operation. This field is used to detect looping while
+ servicing a distributed operation.
+
+
+ The sending DSA populates this with its own URI, and also the URIs of
+ any DSAs that have already been chained to. The receiving DSA
+ examines this list of URIs and returns a loopDetect error if it finds
+ that any of the addresses and DNs in the listed URI's represent it's
+ own.
+
+
+3.2.1.4 ChainedRequestValue.chainingArguments.searchScope
+
+
+ See Section 3.1.5.
+
+
+3.2.1.5 ChainedRequestValue.chainingArguments.searchedSubtrees
+
+
+ See Section 3.1.6.
+
+
+
+
+
+
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+
+
+
+3.2.2 ChainedRequestValue.operationRequest
+
+
+ This holds the original LDAP operation request. This is restricted
+ to a subset of all LDAP operations. Namely, the following LDAP
+ operation types are not allowed:
+
+
+ o Abandon/Cancel operations. When an abandon or cancel operation
+ needs to be chained, it is sent to the remote DSA as-is. This is
+ because there is no need to track it for loop detection or pass on
+ any other information normally found in ChainingArguments.
+ o Unbind. Again, there is no need to send chaining-related
+ information to a DSA to perform an unbind. DSAs which chain
+ operations maintain connections as they see fit.
+ o Chained Operation. When a DSA receives a chained operation, and
+ must again chain that operation to a remote DSA, it sends a
+ ChainedRequest where the ChainedRequestValue.operationRequest is
+ that of the incoming ChainedRequestValue.operationRequest.
+
+
+3.3 Chained Response
+
+
+ The Chained Response is sent as an LDAP IntermediateResponse
+ [RFC3771], or LDAP ExtendedResponse [RFC2251], depending on whether
+ the operation is complete or not. In either case, the responseName
+ is omitted. For intermediate responses, the
+ IntermediateResponse.responseValue is the BER encoding of the
+ ChainedIntermediateResponseValue ASN.1 definition. For completed
+ operations, the ExtendedResponse.value is the BER encoding of the
+ ChainedFinalResponseValue ASN.1 definition.
+
+
+ ChainedIntermediateResponseValue ::= SEQUENCE {
+
+
+ chainedResults ChainingResults,
+ operationResponse IntermediateResponse }
+
+
+ ChainedFinalResponseValue ::= SEQUENCE {
+
+
+ chainedResults ChainingResults,
+ operationResponse FinalResponse }
+
+
+ ChainingResults ::= SEQUENCE {
+
+
+ searchedSubtrees [0] SearchedSubtrees OPTIONAL,
+ ... }
+
+
+ IntermediateResponse ::= SEQUENCE {
+
+
+ Response ::= CHOICE {
+
+
+
+
+
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+
+
+
+
+ searchResEntry SearchResultEntry,
+ searchResRef SearchResultReference,
+ intermediateResponse IntermediateResponse
+ ... },
+ controls [0] Controls COPTIONAL }
+
+
+ FinalResponse ::= SEQUENCE {
+
+
+ Response ::= CHOICE {
+
+
+ bindResponse BindResponse,
+ searchResDone SearchResultDone,
+ modifyResponse ModifyResponse,
+ addResponse AddResponse,
+ delResponse DelResponse,
+ modDNResponse ModifyDNResponse,
+ compareResponse CompareResponse,
+ extendedResp ExtendedResponse,
+ ... },
+ controls [0] Controls COPTIONAL }
+
+
+ BindResponse, SearchResultEntry, SearchResultDone,
+ SearchResultReference, ModifyResponse, AddResponse, DelResponse,
+ ModifyDNResponse, CompareResponse, ExtendedResponse, and Controls are
+ defined in [RFC2251]. IntermediateResponse is defined in [RFC3771].
+
+
+3.3.1 ChainingResults
+
+
+ In general, this is used to convey additional information that may
+ needed in the event that the operation needs to be progressed
+ further.
+
+
+3.3.1.1 ChainingResults.searchedSubtrees
+
+
+ Each value of this field indicates that a particular subtree below
+ the target object has already been searched. This is particularly
+ useful while chaining search operations during operation evaluation
+ caused by the presence of a DSA of type nssr. Each DSA referenced by
+ the nssr holds one or more naming contexts subordinate to the nssr
+ DSE. The ChainingResults.searchedSubtrees field allows the DSA being
+ chained to, to inform the sending DSA which subordinate naming
+ contexts have been searched. This information may be passed to
+ further DSAs listed on the nssr in order to reduce the possibility of
+ duplicate entries being returned.
+
+
+
+
+
+
+
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+
+
+
+3.3.2 ChainedIntermediateResponseValue.intermediateResponse and
+ ChainedFinalResponseValue.finalResponse
+
+
+ This holds the directory operation response message tied to the
+ ChainedRequestValue.operationRequest.
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
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+
+
+
+4. Distributed Procedures
+
+
+ For the purposes of describing a distributed operation, operations
+ are said to consist of two major phases -- name resolution and
+ operation evaluation. These terms are adopted from [X518]. Name
+ resolution is the act of locating a DSE said to be held locally by a
+ DSA given a distinguished name (DN). Operation evaluation is the act
+ of performing the operation after the name resolution phase is
+ complete.
+
+
+ Furthermore, there are two modes of distributing an operation --
+ chaining, and returning referrals. Chaining is the act of forwarding
+ an unfinished operation to another DSA for completion (this may
+ happen during name resolution or operation evaluation). In this
+ case, the forwarding DSA sends a chained operation to a receiving
+ DSA, which attempts to complete the operation. Alternately, the DSA
+ may return a referral (or intermediate referral), and the client may
+ use that referral in order to forward the unfinished operation to
+ another DSA. Whether the operation is distributed via chaining or
+ referrals is a decision left to the DSA and or DUA.
+
+
+ The term 'intermediate referral' describes a referral returned during
+ the operation evaluation phase of an operation. These include
+ searchResultReferences, referrals returned with an
+ intermediateResponse [RFC3771], or future referrals which indicate
+ that they are intermediate referrals.
+
+
+ An operation which is distributed while in the operation evaluation
+ phase is termed a 'sub-operation'.
+
+
+ This document inserts a step between the two distributed operation
+ phases in order to commonize the data and processes followed prior to
+ chaining an operation or returning a referral. This step consists of
+ populating a ContinuationReference data type.
+
+
+4.1 Name resolution
+
+
+ Before evaluating (enacting) most directory operations, the DSE named
+ by the target (often called the base DN) of the operation must be
+ located . This is done by evaluating the RDNs of the target DN one
+ at a time, starting at the rootmost RDN. Each RDN is compared to the
+ DSEs held by the DSA until the set of RDNs is exhausted, or an RDN
+ cannot be found.
+
+
+ If the DSE named by the target is found to be local, the name
+ resolution phase of the operation completes and the operation
+ evaluation phase begins.
+
+
+
+
+
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+
+
+
+ If it is found that the target does not name a local DSE nor a DSE
+ that may held by another DSA, it is said that the target does not
+ exist, and the operation fails with noSuchObject (subject to local
+ policy).
+
+
+ If it is found that the DSE named by the target is non-local to the
+ DSA, but may reside elsewhere, name resolution is said to be
+ incomplete. In this case, the operation may be distributed by
+ creating a ContinuationReference (Section 4.3) and either chaining
+ the operation (Section 4.4 and Section 4.5)or returning a referral
+ (Section 4.9).
+
+
+4.1.1 Determining that a named DSE is local to a DSA
+
+
+ If a DSE held by a DSA falls within a naming context held by the DSA,
+ or is the root DSE on a first-level DSA, it is said to be local to
+ that DSA
+
+
+4.1.2 Determining that a named DSE does not exist
+
+
+ A named DSE is said to not exist if, during name resolution the DSE
+ is not found, but if found it would fall within a naming context held
+ by the DSA.
+
+
+4.1.3 Determining that a named DSE is non-local
+
+
+ If a named DSE is niether found to be local to the DSA, nor found to
+ not exist, it is said to be non-local to a DSA. In this case, it is
+ indeterminate whether the named DSE exists.
+
+
+ When a named DSE is found to be non-local, there should be
+ distributed knowledge information available to be used to either
+ return a referral or chain the operation.
+
+
+4.1.3.1 Locating distributed knowledge information for a non-local
+ target
+
+
+ If it has been determined that a target names a non-local DSE,
+ distributed knowledge information may be found by first examining the
+ DSE named by the target, and subsequently all superior DSEs beginning
+ with the immediate superior and ending with the root, until an
+ examined DSE is one of types:
+
+
+ {TODO: should DSE types be all caps? It would be easier to read.}
+ o subr
+ o supr
+ o immsupr
+
+
+
+
+
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+
+
+
+ o xr
+ o nssr
+
+
+ The examined DSE which is of one of these types holds the distributed
+ knowledge information for the non-local named target. This DSE is
+ said to be the found distributed knowledge information of the
+ non-local target. This found distributed knowledge information may
+ then be used to distribute the operation.
+
+
+ If no examined DSEs are of any of these types, the distributed
+ knowledge information is mis-configured, and the error
+ invalidReference is returned.
+
+
+4.1.4 Special case for the Add operation
+
+
+ During the name resolution phase of the Add operation, the immediate
+ parent of the base DN is resolved.
+
+
+ If the immediate parent of the entry to be added is a DSE of type
+ nssr, then further interrogation is needed to ensure that the entry
+ to be added does not exist. Methods for doing this are found in
+ Section 4.11. {TODO: don't make this mandatory. Also, it doesn't
+ work without transaction semantics. Same prob in the mod dn below.}.
+
+
+4.1.5 Special case for the ModifyDN operation
+
+
+ When the modifyDN operation includes a newSuperior name, it must be
+ resolved as well as the base DN being modified. If either of these
+ result in a non-local name, the name causing the operation to be
+ distributed should be conveyed (Section 4.3.5). {TODO: also mention
+ access control problems, and mention (impl detail) that
+ affectsmultidsa can be used.}
+
+
+ If during operation evaluation of a ModifyDN operation, the
+ newSuperior names a DSE type of nssr, then further interrogation is
+ needed to ensure that the entry to be added does not exist. Methods
+ for doing this are found in Section 4.11.
+
+
+4.2 Operation Evaluation
+
+
+ Once name resolution has completed. The DSE named in the target has
+ been found to be local to a DSA. At this point the operation can be
+ carried out. During operation evaluation distributed knowledge
+ information may be found that may cause the DSA to distribute the
+ operation. When this happens, the operation may be distributed by
+ creating a ContinuationReference (Section 4.3) and either chaining
+ the operation (Section 4.4 and Section 4.5)or returning a referral
+ (Section 4.9).
+
+
+
+
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+
+
+
+ If, during the location of the distributed knowledge information, the
+ distributed knowledge information is found to be mis-configured,
+ operation semantics are followed (some operations may call for an
+ error to be returned, while others call for the error to be ignored).
+ {TODO: either make this more specific, or less specific, or just toss
+ it out.}
+
+
+4.2.1 Search operation
+
+
+ During operation evaluation of a search operation, the DSA must
+ determine whether there is distributed knowledge information in the
+ scope of the search. Any DSE in the search scope which is of the
+ following types is considered to be 'found distributed knowledge
+ information' {TODO: use a better term than found distributed
+ knowledge information} in the search scope:
+
+
+ o subr
+ o nssr (see nssr note)
+ o xr {TODO: I think xr only qualifies when an alias is dereferenced
+ to an xr. Otherwisw, there should always be a subr above the xr
+ if it falls in the search scope.}
+
+
+ Note that due to alias dereferencing, the search scope may expand to
+ include entries outside of the scope originally specified in the
+ search operation.
+
+
+ Nssr Note: A DSE of type nssr is only considered to be found
+ distributed knowledge information when the scope of the search
+ includes entries below it. For example, when the search scope is
+ wholeSubtree or subordinateSubtree and a DSE of type nssr is found in
+ the scope, or if the search scope is singleLevel and the target
+ object names a DSE of type nsssr.
+
+
+ {TODO: The following sections are talking about how the continuation
+ reference is to be populated. Move to next secion. Can probably
+ just say that whole subtree or subordinare subtree encountering nssr,
+ and single level rooted at nssr result in a continuation reference.
+ base at, and single level above do not result in a continuation
+ reference.}
+
+
+4.2.1.1 Search operation with singleLevel scope
+
+
+ If distributed knowledge information is found during operation
+ evaluation of a search with a singleLevel scope, it will cause the
+ resulting ContinuationReference.searchScope to be set to baseObject.
+
+
+
+
+
+
+
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+
+
+
+4.2.1.2 Search operation encountering nssr knowledge reference
+
+
+ When a search operation encounters distributed knowledge information
+ which is a DSE type of nssr during operation evaluation, the
+ following instructions are followed:
+
+
+ Note that when a search operation is being progressed due to nssr
+ knowledge information, the subsequent distributed progression of the
+ search is caused to be applied to each DSA listed as non-specific
+ knowledge information (This is talked about in Section 4.3.2). In
+ the event that multiple DSAs listed in the knowledge information hold
+ copies of the same directory entries, the 'already searched' and
+ 'duplicate elimination' mechanisms SHOULD be used to prevent
+ duplicate search result entries from ultimately being returned.
+
+
+4.2.1.2.1 wholeSubtree search scope
+
+
+ When the search scope is wholeSubtree, the
+ ContinuationReference.searchScope is set to subordinateSubtree.
+ Because the ContinuationReference.referrenceType is set to
+ nonSpecificSubordinate, the receiving protocol peer allows (and
+ expects) name resolution to stop at an immsupr DSE type which is
+ treated as a local DSE. The subordinateSubtree scope instructs the
+ receiving protocol peer to exclude the target object from the
+ sub-search.
+
+
+4.2.1.2.2 singleLevel search scope
+
+
+ When the search scope is singleLevel, and the base DN is resolved to
+ a DSE of type nssr, subsequent distributed progressions of the search
+ are caused to use the same base DN, and a scope of singleLevel.
+ Receiving protocol peers will only apply the search to entries below
+ the target object.
+
+
+ When the search scope is singleLevel and an evaluated DSE is of type
+ nssr, no special handling is required. The search is applied to that
+ DSE if it is of type entry.
+
+
+4.2.1.2.3 baseObject search scope
+
+
+ No special handling is needed when the search scope is baseObject and
+ the base DN is an nssr DSEType. The search is applied to that DSE if
+ it is of type entry.
+
+
+4.2.1.3 Search operation rooted at an nssr DSE type
+
+
+ (TODO: a subordinateSubtree scope needs to change to wholeSubtree if
+ references are found.)
+
+
+
+
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+
+
+
+4.3 Populating the ContinuationReference
+
+
+ When an entry is found to be non-local to a DSA (whether during name
+ resolution or operation evaluation), the DSA prepares for operation
+ distribution by generating a ContinuationReference. This is a
+ conceptual step, given to help explain the interactions that occur
+ between discovering that an operation must be distributing, and
+ actually invoking the operation distribution mechanism.
+ Implementations are not required to perform this step, but will
+ effectively work with the same information.
+
+
+ After the ContinuationReference has been created, the DSA may choose
+ to chain the operation or return a referral (or intermediate
+ referral(s)).
+
+
+ the ContinuationReference is made up of data held on the found
+ distributed knowledge information, as well as state information
+ gained during name resolution or operation evaluation.
+
+
+4.3.1 Conveying the Target Object
+
+
+ The consumer of the ContinuationReference will examine various fields
+ in order to determine the target object name of the operation being
+ progressed. The fields examined are the localReference and
+ remainingName.
+
+
+ If name resolution did not complete, and the found distributed
+ knowledge information names the same DSE as the base DN of the
+ operation, the ContinuationReference MAY omit the localReference
+ and/or remainingName fields.
+
+
+ localReference is populated with the name of the found distributed
+ knowledge information DSE. In the event that the root object holds
+ the distributed knowledge information, this field will be populated
+ with an empty DN. Contrast this with the omission of this field.
+
+
+ referenceType is populated with a value reflecting the reference type
+ of the localReference DSE.
+
+
+ remainingName is populated with the RDNSequence which has not yet
+ been resolved. This is the difference between the localReference
+ value and the name of the DSE to be resolved.
+
+
+ In cases where the DSE named by the {TODO, use a dash or different
+ term to make 'found distributed knowledge' more like a single term}
+ found distributed knowledge is not the same as the base DN of the
+ operation, the ContinuationReference must contain the localReference
+ and/or remainingName fields. Such cases include but are not limited
+
+
+
+
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+
+
+
+ to:
+
+
+ o Distributed knowledge information is found during operation
+ evaluation.
+ o Aliases were dereferenced during name resolution.
+ o Name resolution did not complete and there were remaining RDNs to
+ be resolved.
+
+
+4.3.2 Conveying the Remote DSA
+
+
+ The referralURI field must contain at least one value. Each
+ referralURI value must hold a referralURI.accessPoint. Other
+ requirements on this field as noted may also apply.
+
+
+ Note for nssr DSE types: During operation evaluation, if a DSE of
+ type nssr causes the operation to be distributed (the scenarios in
+ Section 4.2.1.2 are an example), then an intermediate referral {TODO:
+ this is talking about referral/intermediate referral, but this
+ section is only dealing with populating continuation reference} is
+ returned for each value of the ref attribute, where each intermediate
+ referral only holds a single referralURI value.
+
+
+4.3.3 Conveying new search scope
+
+
+ During the evaluation of the search operation, the instructions in
+ Section 4.2.1.2.1 and Section 4.2.1.2.2 are followed and the
+ searchScope field is updated with the new search scope.
+
+
+4.3.4 Preventing duplicates
+
+
+ In order to prevent duplicate entries from being evaluated while
+ progressing a search operation, the searchedSubtrees field is
+ populated with any naming context below the
+ ContinuationReference.targetObject which have been fully searched.
+
+
+ During the evaluation of the search operation, if the scope is
+ wholeSubtree, it is possible that the DSA may search the contents of
+ a naming context which is subordinate to another naming context which
+ is subordinate to the search base (See figure).
+
+
+
+
+
+
+
+
+
+
+
+
+
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+
+
+
+ O X
+ / \
+ / \
+ / \
+ / \
+ \_______O Y
+ /|\
+ / | \
+ / | \
+ / | \
+ A B O C
+ / \
+ / \
+ / \
+ / \
+ \_______/
+
+
+ In this figure, the DSA holds the naming context X and C,Y,X, but not
+ Y,X. If the search base was X, an intermediate referral would be
+ returned for Y,X. The DSA holding Y,X may also hold a copy of C,Y,X.
+ In this case, the receiver of the ContinuationReference benefits by
+ knowing that the DSA already searched C,Y,X so that it can prevent
+ other DSAs from returning those entries again.
+
+
+ Data already searched is in the form of an RDNSequence, consisting of
+ the RDNs relative to the target object.
+
+
+4.3.5 Conveying the Failed Name
+
+
+ At least one DS operation (modifyDN) requires that multiple DNs be
+ resolved (the entry being modified and the newSuperior entry). In
+ this case, the failedName field will be populated with the DN being
+ resolved which failed name resolution. This may aid in the
+ determination of how the operation is to be progressed. If both
+ names are found to be non-local, this field is omitted.
+
+
+4.4 Sending a ChainedRequest
+
+
+ When an entry is found to be non-local to a DSA (whether during name
+ resolution or operation evaluation), the DSA may progress the
+ operation by sending a chained operation to another DSA (or DSAs).
+ The instructions in this section assume that a ContinuationReference
+ has been generated which will be used to form the ChainedRequest. It
+ is also assumed that it can be determined whether the operation is
+ being progressed due to name resolution or due to operation
+ evaluation.
+
+
+ A DSA which is able to chain operations may advertise this by
+
+
+
+
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+
+
+
+ returning a value of IANA-ASSIGNED-OID.2; in the supportedFeatures
+ attribute on the root DSE. {TODO: does this and discovery of the
+ extended op belong in a new 'discovery mechanisms' sections.}
+
+
+4.4.1 Forming a ChainedRequest
+
+
+ The following fields are populated as instructed:
+
+
+4.4.1.1 ChainedRequestValue.chainingArguments.targetObject
+
+
+ The ContinuationReference may convey a new target object. If
+ present, the ContinuationReference.localReference field becomes the
+ candidate target object. Otherwise the candidate target object is
+ assumed to be that of the original directory operation. Note that an
+ empty value in the ContinuationReference.localReference field denotes
+ the root object.
+
+
+ After performing the above determination as to the candidate target
+ object, any RDNSequence in ContinuationReference.remainingName is
+ prepended to the determined candidate target object. This value
+ becomes the ChainedRequestValue.chainingArguments.targetObject. If
+ this value matches the value of the original operation, this field
+ may be omitted.
+
+
+4.4.1.2 ChainedRequestValue.chainingArguments.referenceType
+
+
+ This is populated with the
+ ContinuationReference.referralURI.referenceType.
+
+
+4.4.1.3 ChainedRequestValue.chainingArguments.traceInformation
+
+
+ This is populated as specified in Section 3.2.1.3.
+
+
+4.4.1.4 ChainedRequestValue.chainingArguments.searchScope
+
+
+ This is populated with the
+ ContinuationReference.referralURI.searchScope if present, otherwise
+ by the ContinuationReference.searchScope if present, and not
+ populated otherwise.
+
+
+4.4.1.5 ChainedRequestValue.chainingArguments.searchedSubtrees
+
+
+ This is populated with ContinuationReference.searchedSubtrees, as
+ well as any previously received values of
+ ChainedFinalResponseValue.chainingResults.searchedSubtrees or
+ ChainedIntermediateResponseValue.chainingResults.searchedSubtrees
+ which are subordinate, relative to the target object. (If thsi is
+ relative to the target object, it can't contain non-relative
+
+
+
+
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+
+
+
+ subtrees)
+
+
+4.4.1.6 ChainedRequestValue.operationRequest
+
+
+ This is populated with the original directory operation request.
+
+
+4.4.2 Attempting Each Referral URI
+
+
+ A ContinuationReference consists of one or more referralURIs which
+ represent(s a) remote DSA(s). The chaining DSA attempts to chain to
+ each of these DSAs until one succeeds in completing the operation.
+ An operation is considered to be completed if it reaches the remote
+ DSA and a response is sent back that indicates that the operation was
+ executed. Operations which are sent to the remote DSA, but don't
+ complete are indicated by a result code of unavailable or busy. A
+ result code of protocolError may indicate that the DSA does not
+ support the chained operation, and in this case, it is also treated
+ as an uncompleted operation. Other errors may in the future specify
+ that they also indicate non-completion. Note that the response may
+ itself contain referral(s), these are still considered completed
+ operations and thus would subsequently be handled and chained.
+ {TODO: could use soft/hard, or transient/permanent
+ referral/non-referral error terms here.}
+
+
+4.4.3 Loop Prevention
+
+
+ Prior to sending a ChainedRequest, the DSA may attempt to prevent
+ looping scenarios by comparing {TODO: what matching rule is used?
+ Suggest we don't convert dns names to ip addresses due to NATs} the
+ address of the remote DSA and target object to the values of
+ ChainedRequestValue.chainingArguments.traceInformation. If a match
+ is found, the DSA returns a loopDetect error. Note that while this
+ type of loop prevention aids in detecting loops prior to sending data
+ to a remote DSA, it is not a substitute for loop detection (Section
+ Section 4.6.2). This is because the sending DSA is only aware of a
+ single address on which the receiving DSA accepts connections.
+
+
+4.5 Emulating the Sending of a ChainedRequest
+
+
+ When it is determined that the operation cannot be distributed by
+ means of the ChainedRequest, the chaining DSA may instead emulate the
+ steps involved in chaining the operation. These steps consist of
+ performing loop prevention, forming a new directory operation request
+ from the original request and possibly updating the base DN, search
+ scope, and search filter(in order to emulate searchedSubtrees), and,
+ similar to the steps in Section 4.4.2, attempting to send the
+ operation request to each DSA listed in the
+ ContinuationReference.referralURI until one succeeds in completing
+
+
+
+
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+
+
+
+ the operation.
+
+
+ {TODO: We need a way (control) to tell the receiver to allow name
+ resolution to end on the parent of a cp (typically an immsupr). This
+ would be sent when the ContinuationReference.referenceType is
+ nonSpecificSubordinate}
+
+
+4.5.1 Emulated Loop Detection
+
+
+ For this step, the loop prevention instructions in Section 4.4.3 are
+ followed. Note that this method of loop detection may actually allow
+ some looping to occur before the loop is detected.
+
+
+4.5.2 Forming the New Request
+
+
+ The new directory operation request is formed from the fields of the
+ original request, and the following fields may be updated:
+
+
+ o The base DN is formed from the new target object as determined by
+ following the instructions in Section 4.4.1.1 and using the value
+ which would have been placed in
+ ChainedRequestValue.chainingArguments.targetObject.
+ o For the search operation, the scope is populated with
+ ContinuationReference.searchScope if present, otherwise the scope
+ of the original operation request is used.
+ o For the search operation, if the
+ ContinuationReference.searchedSubtrees field is present, causes
+ the search filter to be augmented by adding a filter item of the
+ 'and' CHOICE. The filter consists of {TODO: weasel Kurt into
+ finishing his entryDN draft and reference the appropriate section
+ there. See
+ <http://www.openldap.org/lists/ietf-ldapext/200407/msg00000.html>
+ for context}
+ o Other fields (such as the messageID, and non-critical controls)
+ may also need to be updated or excluded.
+
+
+ If the service being chained to does not support directory
+ operations, other operations may be used as long as they provide the
+ same level as service as those provided by the analogous directory
+ operation.
+
+
+4.6 Receiving a ChainedRequest
+
+
+ A DSA which is able to receive and service a ChainedRequest may
+ advertise this feature by returning a value of IANA-ASSIGNED-OID.1 in
+ the supportedExtension attribute of the root DSE. {TODO: move?}
+
+
+ The ChainedRequestValue data type is the requestValue of an
+
+
+
+
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+
+
+
+ extendedRequest.
+
+
+ In general, receiving and servicing a ChainedRequest consists of
+ performing loop detection and, using components of the
+ ChainedRequestType.chainingArguments along with the
+ ChainedRequestType.operationRequest, service the request.
+
+
+4.6.1 Target Object determination
+
+
+ Prior to checking for a loop condition, the target object must be
+ determined. If the ChainedRequestType.chainingArguments.targetObject
+ field is present, its value becomes the target object. Otherwise,
+ the base DN found in the ChainedRequestType.operationRequest becomes
+ the target object.
+
+
+4.6.2 Loop Detection
+
+
+ The loop detection check happens when a DSA receives a chained
+ operation, prior to acting on the operation. The DSA compares {TODO:
+ matching rule? DNS expansion?} each value of
+ ChainedRequestValue.traceInformation to the list of addresses at
+ which it accepts directory communications. A value of
+ ChainedRequestValue.traceInformation matches when the DSA accepts
+ directory communications on the address found in the
+ ChainedRequestValue.traceInformation value, and the target object (as
+ determined in Section 4.6.1 matches the DN {TODO: using DN matching?}
+ value found in the ChainedRequestValue.traceInformation value. If a
+ match is found the DSA returns a loopDetect result.
+
+
+4.6.3 Processing the ChainedRequestValue.operationRequest
+
+
+ In processing the operationRequest, the DSA uses the target object
+ determined in Section 4.6.1. For search operations, it uses the
+ scope found in ChainedRequestValue.chainingArguments.searchScope, and
+ excludes any subtrees relative to the target object indicated in
+ ChainedRequestValue.chainingArguments.searchedSubtrees.
+
+
+ Responses are returned in the form of a Chained Response.
+
+
+4.7 Returning a Chained Response
+
+
+ When returning responses to a ChainedRequest, the Chained Response as
+ documented in Section 3.3 is used. If the
+ ChainedFinalResponseValue.operationResponse is a searchResultDone,
+ the ChainedFinalResponseValue.chainingResults.searchedSubtrees field
+ is populated with values consisting of the RDNSequence relative to
+ the target object of naming contexts that the DSA searched. See
+ Section 3.3.1.1 for details on why this is done.
+
+
+
+
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+
+
+
+4.7.1 Chained Response resultCode
+
+
+ The resultCode for the Chained Response is distinct from the result
+ code of the ChainedIntermediateResponseValue.intermediateResponse or
+ ChainedFinalResponseValue.finalResponse. If the act of chaining the
+ operation completed, then this value will be success. Other result
+ codes refer to the chained operation itself, and not the result of
+ the embedded operation.
+
+
+4.7.2 Returning referrals in the Chained Response
+
+
+ {TODO: it would be less complicated if rather than using the simple
+ LDAP URL, we used the ContinuationReference type to return referrals
+ and intermediate referrals.} {TODO: We need an example of why we
+ should allow referrals on a chained response. Why not just use the
+ referral field in the operation?}
+
+
+4.8 Receiving a Chained Response
+
+
+ Processing a received Chained Response is generally straight forward
+ -- typically the response is simply extracted and returned, but there
+ are some extra steps to be taken when chaining sub-operations.
+
+
+4.8.1 Handling Sub-operation controls and result codes
+
+
+ When sub-operations are chained, there is the possibility that
+ different result codes will be encountered. Similarly, if controls
+ which elicit response controls were attached to the operation, it's
+ possible that multiple response controls will be encountered. Both
+ of these possibilities require that the chaining DSA take appropriate
+ steps to ensure that the response being returned is correct.
+
+
+ In general, when a result code indicating an error is received, the
+ operation will terminate and the error will be returned. In cases
+ where multiple sub-operations are being concurrently serviced, the
+ operation will terminate and the most relevant, or first received
+ result code is returned -- determining the result code to be returned
+ in this case is a local matter.
+
+
+ A DSA which chains an operation having a control (or controls)
+ attached must ensure that a properly formed response is returned.
+ This requires that the DSA understand and know how to aggrigate the
+ results of all controls which it allows to remain attached to an
+ operation being chained. If the DSA does not understand or support a
+ control which is marked non-critical, it removes the control prior to
+ chaining the operation. The DSA may return
+ unavailableCriticalExtension for critical controls that it cannot or
+ will not chain. {TODO: give SSS as an example?}
+
+
+
+
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+
+
+
+4.8.1.1 Handling referrals during sub-operations
+
+
+ If a referral is returned in response to a sub-operation, the sending
+ DSA may attempt to further chain the operation. In the event that
+ the DSA does not further chain the sub-operation, it will use the
+ referral to construct an intermediate referral, and return it
+ appropriately. When using a referral to construct an intermediate
+ referral, certain transformations may have to happen. For example,
+ when using a referral to construct a searchResultReference, it must
+ be assured that the <dn> field is present, and that the <scope> field
+ is properly updated.
+
+
+4.8.2 Duplicate Elimination
+
+
+ When search result references cause the DSA to chain a search, it is
+ possible that duplicate objects will be returned by different remote
+ DSAs. These duplicate objects must be sensed and not returned.
+
+
+ {TODO: Even though there are costs associated with returning
+ duplicates, is it a worthy exercise to build in an allowance for them
+ to be returned? In other words, do we want to add a way for a client
+ (or administrator) to say "it's ok, return the duplicates, let the
+ client deal with them"? Allowing is seen as a cost benefit to the
+ DSA.}
+
+
+4.9 Returning a Referral or Intermediate Referral
+
+
+ There are two ways in which the fields of the ContinuationReference
+ may be conveyed in a response containing or consisting of referral or
+ intermediate referral. A paired control is introduced for the
+ purpose of soliciting and returning a ContinuationReference. In
+ absence of this control, a referral or intermediate referral may be
+ returned which conveys the information present in the
+ ContinuationReference. A method of converting a
+ ContinuationReference to an LDAP URL is provided for referrals and
+ intermediate referrals which identify LDAP-enabled DSAs. Methods for
+ converting a ContinuationReference to URIs which identify non-LDAP
+ servers is not provided here, but may be specified in future
+ documents, as long as they can represent the data needed to provide
+ the same level of service.
+
+
+4.9.1 ReturnContinuationReference controls
+
+
+ This control is sent when a client wishes to receive a
+ ContinuationReference in the event that a referral or intermediate
+ referral is being returned. If returned, the ContinuationReference
+ will hold all data but the referralURI field. the referralURI values
+ will be held in the referral or intermediate referral (Referral,
+
+
+
+
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+
+
+
+ SearchResultReference, etc.).
+
+
+4.9.1.1 ReturnContinuationReference request control
+
+
+ Solicits the return of a ReturnContinuationReference response control
+ on messages consisting of (or carrying) a referral or intermediate
+ referral. The controlType is IANA-ASSIGNED-OID.3, the criticality is
+ set at the sender's discretion, the controlValue is omitted.
+
+
+4.9.1.2 ReturnContinuationReference response control
+
+
+ In response to the ReturnContinuationReference request control, this
+ holds a ContinuationReference for messages consisting of (or
+ carrying) a referral or intermediate referral. The controlType is
+ IANA-ASSIGNED-OID.3, the controlValue is the BER-encoding of a
+ ContinuationReference. Note that the referralURI field is optionally
+ omitted when the ContinuationReference is sent in this control value.
+ In this event, the URI(s) found in the referral or intermediate
+ referral (Referral, SearchContinuationReference, etc.) are to be used
+ in its stead. {TODO: is returining the referralURI outside an
+ unneeded complication?}
+
+
+4.9.2 Converting a ContinuationReference to an LDAP URL
+
+
+ This section details the way in which an LDAP URL (from the referral
+ or intermediate referral) is used to convey the fields of a
+ ContinuationReference. Where existing LDAP URL fields are
+ insufficient, extensions are introduced. Note that further
+ extensions to the ContinuationReference type require further
+ specifications here. {TODO: explain that each ldap url in the
+ continuation refrerence is examined and converted}
+
+
+ These instructions must be applied to each LDAP URL value within the
+ referral or intermediate referral.
+
+
+4.9.2.1 Conveying the target name
+
+
+ If the <dn> part of the LDAP URL is already present, it is determined
+ to be the candidate target object. Otherwise, the candidate target
+ object comes from the ContinuationReference.localReference. Once the
+ candidate target object is determined, the value of
+ ContinuationReference.remainingName is prepended to the candidate
+ target object. This new value becomes the target object and its
+ string value (as specified by <distinguishedName> in [RFC2253]) is
+ placed in the <dn> part of the LDAP URL.
+
+
+
+
+
+
+
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+
+
+
+4.9.2.2 ContinuationReference.localReference
+
+
+ This is conveyed as an extension. The extype is IANA-ASSIGNED-OID.4
+ or the descriptor 'localReference', and the exvalue is the string DN
+ encoding (as specified by <distinguishedName> in [RFC2253]) of the
+ ContinuationReference.localReference value.
+
+
+4.9.2.3 ContinuationReference.referenceType
+
+
+ This is conveyed as an extension. The extype is IANA-ASSIGNED-OID.5
+ or the descriptor 'referenceType'. If the
+ ContinuationReference.referenceType is one of superior, subordinate,
+ cross, nonSpecificSubordinate, suplier, master, immediateSuperior, or
+ self, the exvalue 'superior', 'subordinate', 'cross',
+ 'nonSpecificSubordinate', 'suplier', 'master', 'immediateSuperior',
+ or 'self' respectively.
+
+
+4.9.2.4 ContinuationReference.searchScope
+
+
+ If the search scope is one of baseObject, singleLevel, or
+ wholeSubtree, then it may be conveyed in the 'scope' part of the LDAP
+ URL as 'base', 'one', or 'sub' respectively. If the search scope is
+ subordinateSubtree, then it may be conveyed in the <extension> form
+ as documented in [LDAP-SUBORD]. If this extension is present, it
+ MUST be marked critical. This ensures that a receiver which is
+ unaware of this extension uses the proper search scope, or fails to
+ progress the operation.
+
+
+4.9.2.5 ContinuationReference.searchedSubtrees
+
+
+ This field is conveyed as an extension. The extype is
+ IANA-ASSIGNED-OID.6 or the descriptor 'searchedSubtrees', and the
+ exvalue is the ContinuationReference.searchedSubtree value encoded
+ according to the following searchedSubtrees ABNF:
+
+
+ searchedSubtrees = 1*(LANGLE searchedSubtree RANGLE)
+ searchedSubtree = <distinguishedName> from [RFC2253]
+ LANGLE = %x3C ; left angle bracket ("<")
+ RANGLE = %x3E ; right angle bracket (">")
+
+
+ Each searchedSubtree represents one RDNSequence value in the
+ ContinuationReference.searchedSubtree field. An example of a
+ searchedSubtrees value containing two searched subtrees is:
+ <dc=example,dc=com><cn=ralph,dc=users,dc=example,dc=com>.
+
+
+4.9.2.6 ContinuationReference.failedName
+
+
+ This field is conveyed as an extension. The extype is
+
+
+
+
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+
+
+
+ IANA-ASSIGNED-OID.7 or the descriptor 'failedName', and the exvalue
+ is the string DN encoding (as specified in [RFC2253]) of the
+ ContinuationReference.failedName value.
+
+
+4.10 Acting on a Referral or Intermediate Referral
+
+
+ When a protocol peer receives a referral or intermediate referral, it
+ may distribute the operation either by sending a ChainedRequest, or
+ by emulating the ChainedRequest. Prior to taking these steps, the
+ protocol peer effectively converts the referral or intermediate
+ referral into a ContinuationReference. Then, acting in the same
+ manner as a DSA would, follows the directions in Section 4.4 if
+ sending a ChainedRequest, or Section 4.5 otherwise.
+
+
+4.10.1 Converting a Referral or Intermediate Referral to a
+ ContinuationReference
+
+
+ A referral or intermediate referral may be converted (or conceptually
+ converted) to a ContinuationReference type in order to follow the
+ distributed operation procedures in Section 4.4, or Section 4.5. The
+ following steps may only be used to convert a referral or
+ intermediate referral containing LDAP URL values. Converting other
+ types of URIs may be specified in future documents as long as the
+ conversion provides the same level of service found here.
+
+
+ o The ContinuationReference.referralURI is populated with all LDAP
+ URL values in the referral or intermediate referral.
+ o The ContinuationReference.localReference populate with the value
+ of the localReference extension value (Section 4.9.2.2) if one
+ exists. Otherwise it is omitted.
+ o The ContinuationReference.referenceType populate with the value of
+ the referenceType extension value (Section 4.9.2.3) if one exists.
+ Otherwise it is omitted.
+ o The ContinuationReference.remainingName is omitted.
+ o The ContinuationReference.searchScope is populated with
+ subordinateSubtree if the subordScope LDAP URL extension
+ [LDAP-SUBORD] is present. If the <scope> field contains te value
+ 'base', 'one', 'sub', or 'subordinates', this filed is populated
+ with baseObject, singleLevel, wholeSubtree, or subordinateSubtree
+ respectively. Otherwise this field is omitted.
+ o The ContinuationReference.searchedSubtrees is populated with any
+ searchedSubtrees LDAP URI extension Section 4.9.2.5 value found on
+ an LDAP URI in the referral or intermediate referral. If none
+ exist, this field is omitted.
+ o The ContinuationReference.failedName is populated with any
+ failedName LDAP URI extension Section 4.9.2.6 value found on an
+ LDAP URI in the referral or intermediate referral. If none exist,
+ this field is omitted.
+
+
+
+
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+
+
+
+ Note that many fields are simply omitted. This is either because
+ they are conveyed within the LDAP URL values themselves, and
+ subsequent instructions will check for their presence, or because
+ they are not needed (they are redundant or not used in further
+ instructions).
+
+
+4.11 Ensuring non-existence of an entry under an nssr
+
+
+ {TODO: add a huge disclaimer here that says without transactional
+ semantics, you can never be sure that the entry didn't get added.
+ Maybe we should just punt on this and say it's a local matter} In
+ order to ensure there are no entries matching the name of the entry
+ to be added or renamed immediately subordinate to an nssr, these
+ steps may be followed.
+
+
+ If the DSA is able and allowed to chain operations, it may contact
+ each of the DSAs listed as access points in the nssr (in the ref
+ attribute) and using a base-level search operation it will determine
+ whether or not the object to be added exists. Note that access
+ control or other policies may hide the entry from the sending DSA.
+ If the entry does not exist on any of the DSAs listed in the nssr,
+ the operation may progress on the local DSA.
+
+
+ If the DSA cannot make this determination, the operation fails with
+ affectsMultipleDSAs.
+
+
+4.12 Mapping a referralURI to an LDAP URI
+
+
+ As with any URI specification which is intended to be used as a URI
+ which conveys referral information, the LDAP URI specification is
+ given a mapping to the elements of a referralURI as specified in.
+ Section 3.1.1.1. These mappings are given here using the ABNF
+ identifiers given in [RFC2255].
+
+
+ referralURI to LDAP URI mapping:
+
+
+ +---------------------------------+---------------------------------+
+ | referralURI element | LDAP URL element |
+ +---------------------------------+---------------------------------+
+ | protocolIdentifier | <scheme> |
+ | | |
+ | accessPoint | <hostport> |
+ | | |
+ | targetObject | <dn>. This must be encoded as a |
+ | | <distinguishedName> as |
+ | | specified in [RFC2253] |
+ | | |
+ | localReference | LDAP URL localReference |
+
+
+
+
+Sermersheim Expires April 24, 2005 [Page 31]
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+
+
+
+ | | extension as specified in |
+ | | Section 4.9.2.2 |
+ | | |
+ | referenceType | LDAP URL referenceType |
+ | | extension as specified in |
+ | | Section 4.9.2.3 |
+ | | |
+ | searchScope | <scope> or LDAP URL subordScope |
+ | | extension as specified in |
+ | | Section 4.9.2.4 |
+ | | |
+ | searchedSubtrees | LDAP URL searchedSubtrees |
+ | | extension as specified in |
+ | | Section 4.9.2.5 |
+ | | |
+ | failedName | LDAP URL failedName extension |
+ | | as specified in Section 4.9.2.6 |
+ +---------------------------------+---------------------------------+
+
+
+
+ 4.13 Using the ManageDsaIT control
+
+
+ This control, defined in [RFC3296], allows the management of the
+ distributed knowledge information held by a DSA, and thus overrides
+ the determinations made during name resolution and operation
+ evaluation. When this control is attached to an operation, all
+ resolved and acted upon DSEs are treated as being local to the DSA.
+ This is true regardless of the phase the operation is in. Thus
+ referrals are never returned and chaining never occurs.
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+Sermersheim Expires April 24, 2005 [Page 32]
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+
+
+
+5. Security Considerations
+
+
+ This document introduces a mechanism (chaining) which can be used to
+ propagate directory operation requests to servers which may be
+ inaccessible otherwise. Implementers and deployers of this
+ technology should be aware of this and take appropriate steps such
+ that firewall mechanisms are not compromised.
+
+
+ This document introduces the ability to return auxiliary data when
+ returning referrals. Measures should be taken to ensure proper
+ protection of this data.
+
+
+ Implementers must ensure that any specified time, size, and
+ administrative limits are not circumvented due to the mechanisms
+ introduced here.
+
+
+6 Normative References
+
+
+ [LDAP-SUBORD]
+ Sermersheim, J., "Subordinate Subtree Search Scope for
+ LDAP", draft-sermersheim-ldap-subordinate-scope-xx (work
+ in progress), July 2004.
+
+
+ [RFC2079] Smith, M., "Definition of an X.500 Attribute Type and an
+ Object Class to Hold Uniform Resource Identifiers (URIs)",
+ RFC 2079, January 1997.
+
+
+ [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
+ Requirement Levels", BCP 14, RFC 2119, March 1997.
+
+
+ [RFC2251] Wahl, M., Howes, T. and S. Kille, "Lightweight Directory
+ Access Protocol (v3)", RFC 2251, December 1997.
+
+
+ [RFC2253] Wahl, M., Kille, S. and T. Howes, "Lightweight Directory
+ Access Protocol (v3): UTF-8 String Representation of
+ Distinguished Names", RFC 2253, December 1997.
+
+
+ [RFC2255] Howes, T. and M. Smith, "The LDAP URL Format", RFC 2255,
+ December 1997.
+
+
+ [RFC2396] Berners-Lee, T., Fielding, R. and L. Masinter, "Uniform
+ Resource Identifiers (URI): Generic Syntax", RFC 2396,
+ August 1998.
+
+
+ [RFC3296] Zeilenga, K., "Named Subordinate References in Lightweight
+ Directory Access Protocol (LDAP) Directories", RFC 3296,
+ July 2002.
+
+
+
+
+
+Sermersheim Expires April 24, 2005 [Page 33]
+Internet-Draft Distributed Procedures for LDAP OperationsOctober 2004
+
+
+
+ [RFC3377] Hodges, J. and R. Morgan, "Lightweight Directory Access
+ Protocol (v3): Technical Specification", RFC 3377,
+ September 2002.
+
+
+ [RFC3383] Zeilenga, K., "Internet Assigned Numbers Authority (IANA)
+ Considerations for the Lightweight Directory Access
+ Protocol (LDAP)", BCP 64, RFC 3383, September 2002.
+
+
+ [RFC3771] Harrison, R. and K. Zeilenga, "The Lightweight Directory
+ Access Protocol (LDAP) Intermediate Response Message", RFC
+ 3771, April 2004.
+
+
+ [X500] International Telephone and Telegraph Consultative
+ Committee, "The Directory - overview of concepts, models
+ and services", ITU-T Recommendation X.500, November 1993.
+
+
+ [X518] International Telephone and Telegraph Consultative
+ Committee, "The Directory - The Directory: Procedures for
+ distributed operation", ITU-T Recommendation X.518,
+ November 1993.
+
+
+ [X680] International Telecommunications Union, "Abstract Syntax
+ Notation One (ASN.1): Specification of basic notation",
+ ITU-T Recommendation X.680, July 2002.
+
+
+ [X690] International Telecommunications Union, "Information
+ Technology - ASN.1 encoding rules: Specification of Basic
+ Encoding Rules (BER), Canonical Encoding Rules (CER) and
+ Distinguished Encoding Rules (DER)", ITU-T Recommendation
+ X.690, July 2002.
+
+
+
+Author's Address
+
+
+ Jim Sermersheim
+ Novell, Inc
+ 1800 South Novell Place
+ Provo, Utah 84606
+ USA
+
+
+ Phone: +1 801 861-3088
+ EMail: jimse@novell.com
+
+
+
+
+
+
+
+
+
+
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+
+
+
+Appendix A. IANA Considerations
+
+
+ Registration of the following values is requested [RFC3383].
+
+
+A.1 LDAP Object Identifier Registrations
+
+
+ It is requested that IANA register upon Standards Action an LDAP
+ Object Identifier in identifying the protocol elements defined in
+ this technical specification. The following registration template is
+ provided:
+
+
+ Subject: Request for LDAP OID Registration
+ Person & email address to contact for further information:
+ Jim Sermersheim
+ jimse@novell.com
+ Specification: RFCXXXX
+ Author/Change Controller: IESG
+ Comments:
+ Seven delegations will be made under the assigned OID:
+ IANA-ASSIGNED-OID.1 ChainedRequest LDAP Extended Operation
+ IANA-ASSIGNED-OID.2 Supported Feature: Can Chain Operations
+ IANA-ASSIGNED-OID.3 ReturnContinuationReference LDAP Controls
+ IANA-ASSIGNED-OID.4 localReference: LDAP URL Extension
+ IANA-ASSIGNED-OID.6 searchedSubtree: LDAP URL Extension
+ IANA-ASSIGNED-OID.7 failedName: LDAP URL Extension
+
+
+A.2 LDAP Protocol Mechanism Registrations
+
+
+ It is requested that IANA register upon Standards Action the LDAP
+ protocol mechanism described in this document. The following
+ registration templates are given:
+
+
+ Subject: Request for LDAP Protocol Mechanism Registration
+ Object Identifier: IANA-ASSIGNED-OID.1
+ Description: ChainedRequest LDAP Extended Operation
+ Person & email address to contact for further information:
+ Jim Sermersheim
+ jimse@novell.com
+ Usage: Extension
+ Specification: RFCXXXX
+ Author/Change Controller: IESG
+ Comments: none
+
+
+ Subject: Request for LDAP Protocol Mechanism Registration
+ Object Identifier: IANA-ASSIGNED-OID.2
+ Description: Can Chain Operations Supported Feature
+ Person & email address to contact for further information:
+
+
+
+
+
+Sermersheim Expires April 24, 2005 [Page 35]
+Internet-Draft Distributed Procedures for LDAP OperationsOctober 2004
+
+
+
+ Jim Sermersheim
+ jimse@novell.com
+ Usage: Feature
+ Specification: RFCXXXX
+ Author/Change Controller: IESG
+ Comments: none
+
+
+ Subject: Request for LDAP Protocol Mechanism Registration
+ Object Identifier: IANA-ASSIGNED-OID.3
+ Description: ReturnContinuationReference LDAP Controls
+ Person & email address to contact for further information:
+ Jim Sermersheim
+ jimse@novell.com
+ Usage: Control
+ Specification: RFCXXXX
+ Author/Change Controller: IESG
+ Comments: none
+
+
+ Subject: Request for LDAP Protocol Mechanism Registration
+ Object Identifier: IANA-ASSIGNED-OID.4
+ Description: localReference LDAP URL Extension
+ Person & email address to contact for further information:
+ Jim Sermersheim
+ jimse@novell.com
+ Usage: Extension
+ Specification: RFCXXXX
+ Author/Change Controller: IESG
+ Comments: none
+
+
+ Subject: Request for LDAP Protocol Mechanism Registration
+ Object Identifier: IANA-ASSIGNED-OID.5
+ Description: referenceType LDAP URL Extension
+ Person & email address to contact for further information:
+ Jim Sermersheim
+ jimse@novell.com
+ Usage: Extension
+ Specification: RFCXXXX
+ Author/Change Controller: IESG
+ Comments: none
+
+
+ Subject: Request for LDAP Protocol Mechanism Registration
+ Object Identifier: IANA-ASSIGNED-OID.6
+ Description: searchedSubtree LDAP URL Extension
+ Person & email address to contact for further information:
+ Jim Sermersheim
+ jimse@novell.com
+ Usage: Extension
+
+
+
+
+
+Sermersheim Expires April 24, 2005 [Page 36]
+Internet-Draft Distributed Procedures for LDAP OperationsOctober 2004
+
+
+
+ Specification: RFCXXXX
+ Author/Change Controller: IESG
+ Comments: none
+
+
+ Subject: Request for LDAP Protocol Mechanism Registration
+ Object Identifier: IANA-ASSIGNED-OID.7
+ Description: failedName LDAP URL Extension
+ Person & email address to contact for further information:
+ Jim Sermersheim
+ jimse@novell.com
+ Usage: Extension
+ Specification: RFCXXXX
+ Author/Change Controller: IESG
+ Comments: none
+
+
+A.3 LDAP Descriptor Registrations
+
+
+ It is requested that IANA register upon Standards Action the LDAP
+ descriptors described in this document. The following registration
+ templates are given:
+
+
+ Subject: Request for LDAP Descriptor Registration
+ Descriptor (short name): localReference
+ Object Identifier: IANA-ASSIGNED-OID.4
+ Person & email address to contact for further information:
+ Jim Sermersheim
+ jimse@novell.com
+ Usage: URL Extension
+ Specification: RFCXXXX
+ Author/Change Controller: IESG
+ Comments: none
+
+
+ Subject: Request for LDAP Descriptor Registration
+ Descriptor (short name): referenceType
+ Object Identifier: IANA-ASSIGNED-OID.5
+ Person & email address to contact for further information:
+ Jim Sermersheim
+ jimse@novell.com
+ Usage: URL Extension
+ Specification: RFCXXXX
+ Author/Change Controller: IESG
+ Comments: none
+
+
+ Subject: Request for LDAP Descriptor Registration
+ Descriptor (short name): searchedSubtree
+ Object Identifier: IANA-ASSIGNED-OID.6
+ Person & email address to contact for further information:
+
+
+
+
+
+Sermersheim Expires April 24, 2005 [Page 37]
+Internet-Draft Distributed Procedures for LDAP OperationsOctober 2004
+
+
+
+ Jim Sermersheim
+ jimse@novell.com
+ Usage: URL Extension
+ Specification: RFCXXXX
+ Author/Change Controller: IESG
+ Comments: none
+
+
+ Subject: Request for LDAP Descriptor Registration
+ Descriptor (short name): failedName
+ Object Identifier: IANA-ASSIGNED-OID.7
+ Person & email address to contact for further information:
+ Jim Sermersheim
+ jimse@novell.com
+ Usage: URL Extension
+ Specification: RFCXXXX
+ Author/Change Controller: IESG
+ Comments: none
+
+
+A.4 LDAP Result Code Registrations
+
+
+ It is requested that IANA register upon Standards Action the LDAP
+ result codes described in this document. The following registration
+ templates are given:
+
+
+ Subject: Request for LDAP Result Code Registration
+ Result Code Name: invalidReference
+ Person & email address to contact for further information:
+ Jim Sermersheim
+ jimse@novell.com
+ Usage: URL Extension
+ Specification: RFCXXXX
+ Author/Change Controller: IESG
+ Comments: none
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+Sermersheim Expires April 24, 2005 [Page 38]
+Internet-Draft Distributed Procedures for LDAP OperationsOctober 2004
+
+
+
+Intellectual Property Statement
+
+
+ The IETF takes no position regarding the validity or scope of any
+ Intellectual Property Rights or other rights that might be claimed to
+ pertain to the implementation or use of the technology described in
+ this document or the extent to which any license under such rights
+ might or might not be available; nor does it represent that it has
+ made any independent effort to identify any such rights. Information
+ on the procedures with respect to rights in RFC documents can be
+ found in BCP 78 and BCP 79.
+
+
+ Copies of IPR disclosures made to the IETF Secretariat and any
+ assurances of licenses to be made available, or the result of an
+ attempt made to obtain a general license or permission for the use of
+ such proprietary rights by implementers or users of this
+ specification can be obtained from the IETF on-line IPR repository at
+ http://www.ietf.org/ipr.
+
+
+ The IETF invites any interested party to bring to its attention any
+ copyrights, patents or patent applications, or other proprietary
+ rights that may cover technology that may be required to implement
+ this standard. Please address the information to the IETF at
+ ietf-ipr@ietf.org.
+
+
+
+Disclaimer of Validity
+
+
+ This document and the information contained herein are provided on an
+ "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
+ OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
+ ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
+ INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
+ INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
+ WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
+
+
+
+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.
+
+
+
+Acknowledgment
+
+
+ Funding for the RFC Editor function is currently provided by the
+ Internet Society.
+
+
+
+
+
+Sermersheim Expires April 24, 2005 [Page 39]
\ No newline at end of file
projects / openldap / commitdiff