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.
-
-
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+\f
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+ - 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.
-
+
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+\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
+
+
+
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+\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
-
-
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- 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.
+
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+\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.
-
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- 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.
+
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+\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.
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
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+Sermersheim Internet-Draft - Expires Aug 2005 Page 63
+\f
Lightweight Directory Access Protocol Version 3
-
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\ No newline at end of file
+Sermersheim Internet-Draft - Expires Aug 2005 Page 64
+\f
\ No newline at end of file
projects / openldap / blobdiff