INTERNET-DRAFT Kurt D. Zeilenga Intended Category: Standard Track OpenLDAP Foundation Expires in six months 26 October 2003 LDAP Read Entry Controls 1. Status of this Memo This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC2026. This document is intended to be, after appropriate review and revision, submitted to the RFC Editor as a Standard Track document. Distribution of this memo is unlimited. Technical discussion of this document will take place on the IETF LDAP Extensions mailing list . Please send editorial comments directly to the author . Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet-Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as ``work in progress.'' The list of current Internet-Drafts can be accessed at . The list of Internet-Draft Shadow Directories can be accessed at . Copyright (C) The Internet Society (2003). All Rights Reserved. Please see the Full Copyright section near the end of this document for more information. Abstract This specification describes controls which can be attached to a Lightweight Directory Access Protocol (LDAP) update request to obtain copies of the target entry before and/or after the requested update is applied. Zeilenga LDAP Read Entry Controls [Page 1] INTERNET-DRAFT draft-zeilenga-ldap-readentry-01 26 October 2003 1. Background and Intent of Use This specification describes controls [RFC2251] which can be attached to Lightweight Directory Access Protocol (LDAP) [RFC3377] update requests to request and return copies of the target entry. One request control, called the Pre-Read request control, indicates that a copy of the entry before application of update is to be returned. Another control, called the Post-Read request control, indicates that a copy of the entry after application of the update is to be returned. Each request control has a corresponding response control used to return the entry. The functionality offered by these controls is based upon similar functionality in the X.500 Directory Access Protocol (DAP) [X.511]. The Pre-Read controls may be used to obtain replaced or deleted values of modified attributes or a copy of the entry being deleted. The Post-Read controls may be used to obtain values of operational attributes, such as the 'entryUUID' [EntryUUID] and 'modifytimestamp' [RFC2252] attributes, updated by the server as part of the update operation. 2. Terminology Protocol elements are described using ASN.1 [X.680] with implicit tags. The term "BER-encoded" means the element is to be encoded using the Basic Encoding Rules [X.690] under the restrictions detailed in Section 5.1 of [RFC2251]. DN stands for Distinguished Name. DSA stands for Directory System Agent (i.e., a directory server). DSE stands for DSA-specific Entry. The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119]. 3. Read Entry Controls 3.1. The Pre-Read Controls The Pre-Read request and response controls are identified by the IANA-ASSIGNED-OID.1 object identifier. Servers implementing these controls SHOULD publish IANA-ASSIGNED-OID.1 as a value of the 'supportedControl' [RFC2252] in their root DSE. Zeilenga LDAP Read Entry Controls [Page 2] INTERNET-DRAFT draft-zeilenga-ldap-readentry-01 26 October 2003 The Pre-Read request control is an LDAP Control [RFC2251] whose controlType is IANA-ASSIGNED-OID.1 and controlValue is a BER-encoded AttributeDescriptionList [RFC2251]. The criticality may be TRUE or FALSE. This control is appropriate for the modifyRequest, delRequest, and modDNRequest LDAP messages. The corresponding response control is a LDAP Control whose controlType is IANA-ASSIGNED-OID.1 and the controlValue, an OCTET STRING, contains a BER-encoded SearchResultEntry. The criticality may be TRUE or FALSE. This control is appropriate for the modifyResponse, delResponse, and modDNResponse LDAP messages with a resultCode of success (0). When the request control is attached to an appropriate update LDAP request, the control requests the return of a copy of target entry prior to the application of the update. The AttributeDescriptionList indicates which attributes are requested to appear in the copy. There are two special AttributeDescriptions which may be included in the list, "*" and "+". "*" requests all user attributes. "+" requests all operational attributes. If the list is empty, all user attributes are requested. If the list contains an unrecognized attribute type, that type is simply ignored. If all attribute types are unrecognized, no attributes are to be returned. The server is to return a SearchResultEntry containing, subject to access controls and other constraints, values of the requested attributes. The normal processing of the update operation and the processing of this control MUST be performed as one atomic action isolated from other update operations. If the update operation fails, no response control is provided. 3.2. The Post-Read Controls The Post-Read request and response controls are identified by the IANA-ASSIGNED-OID.2 object identifier. Servers implementing these controls SHOULD publish IANA-ASSIGNED-OID.2 as a value of the 'supportedControl' [RFC2252] in their root DSE. The Post-Read request control is an LDAP Control [RFC2251] whose controlType is IANA-ASSIGNED-OID.2 and controlValue, an OCTET STRING, contains a BER-encoded AttributeDescriptionList [RFC2251]. The criticality may be TRUE or FALSE. This control is appropriate for the addRequest, modifyRequest, and modDNRequest LDAP messages. The corresponding response control is a LDAP Control whose controlType is IANA-ASSIGNED-OID.2 and controlValue is a BER-encoded Zeilenga LDAP Read Entry Controls [Page 3] INTERNET-DRAFT draft-zeilenga-ldap-readentry-01 26 October 2003 SearchResultEntry. The criticality may be TRUE or FALSE. This control is appropriate for the addResponse, modifyResponse, and modDNResponse LDAP messages with a resultCode of success (0). When the request control is attached to an appropriate update LDAP request, the control requests the return of a copy of target entry after the application of the update. The AttributeDescriptionList indicates which attributes are requested to appear in the copy. There are two special AttributeDescriptions which may be included in the list, "*" and "+". "*" requests all user attributes. "+" requests all operational attributes. If the list is empty, all user attributes are requested. If the list contains an unrecognized attribute type, that type is simply ignored. If all attribute types are unrecognized, no attributes are to be returned. The server is to return a SearchResultEntry containing, subject to access controls and other constraints, values of the requested attributes. The normal processing of the update operation and the processing of this control MUST be performed as one atomic action isolated from other update operations. If the update operation fails, no response control is provided. 4. Interaction with other controls The Pre- and Post-Read controls may be combined with each other and/or with a variety of other controls. When combined with the assertion control [ASSERT], the manageDsaIT control [RFC3296], and/or the proxy authorization control [PROXYAUTH], the semantics of each control included in the combination apply. The Pre- and Post-Read controls may be combined with other controls as detailed in other technical specifications. 5. Security Considerations The controls defined in this document extend update operations to support read capabilities. Servers MUST ensure that the client is authorized both for reading of the information provided in this control in addition to ensuring the client is authorized to perform the requested directory update. Implementors of this (or any) LDAP extension should be familiar with general LDAP security considerations [RFC3377]. 6. IANA Considerations Zeilenga LDAP Read Entry Controls [Page 4] INTERNET-DRAFT draft-zeilenga-ldap-readentry-01 26 October 2003 Registration of the following protocol values [RFC3383] is requested. 6.1. Object Identifier It is requested that IANA register an LDAP Object Identifier to identify LDAP protocol elements defined in this document. Subject: Request for LDAP Object Identifier Registration Person & email address to contact for further information: Kurt Zeilenga Specification: RFC XXXX Author/Change Controller: IESG Comments: Identifies the LDAP Read Entry Controls 6.2. LDAP Protocol Mechanisms It is requested that IANA register the LDAP Protocol Mechanism described in this document. Subject: Request for LDAP Protocol Mechanism Registration Object Identifier: IANA-ASSIGNED-OID.1 Description: LDAP Pre-read Control Person & email address to contact for further information: Kurt Zeilenga Usage: Control Specification: RFC XXXX Author/Change Controller: IESG Comments: none in 2 Subject: Request for LDAP Protocol Mechanism Registration Object Identifier: IANA-ASSIGNED-OID.2 Description: LDAP Post-read Control Person & email address to contact for further information: Kurt Zeilenga Usage: Control Specification: RFC XXXX Author/Change Controller: IESG Comments: none in 2 7. Acknowledgment The LDAP Pre- and Post-Read controls are modeled after similar Zeilenga LDAP Read Entry Controls [Page 5] INTERNET-DRAFT draft-zeilenga-ldap-readentry-01 26 October 2003 capabilities offered in the DAP [X.511]. 8. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14 (also RFC 2119), March 1997. [RFC2251] Wahl, M., T. Howes and S. Kille, "Lightweight Directory Access Protocol (v3)", RFC 2251, December 1997. [RFC2252] Wahl, M., A. Coulbeck, T. Howes, and S. Kille, "Lightweight Directory Access Protocol (v3): Attribute Syntax Definitions", RFC 2252, December 1997. [RFC2830] Hodges, J., R. Morgan, and M. Wahl, "Lightweight Directory Access Protocol (v3): Extension for Transport Layer Security", RFC 2830, May 2000. [RFC3296] Zeilenga, K., "Named Subordinate References in Lightweight Directory Access Protocol (LDAP) Directories", RFC 3296, July 2002. [RFC3377] Hodges, J. and R. Morgan, "Lightweight Directory Access Protocol (v3): Technical Specification", RFC 3377, September 2002. [X.680] International Telecommunication Union - Telecommunication Standardization Sector, "Abstract Syntax Notation One (ASN.1) - Specification of Basic Notation", X.680(1997) (also ISO/IEC 8824-1:1998). [X.690] International Telecommunication Union - Telecommunication Standardization Sector, "Specification of ASN.1 encoding rules: Basic Encoding Rules (BER), Canonical Encoding Rules (CER), and Distinguished Encoding Rules (DER)", X.690(1997) (also ISO/IEC 8825-1:1998). [PROXYAUTH] Weltman, R., "LDAP Proxy Authentication Control", draft- weltman-ldapv3-proxy-xx.txt, a work in progress. [ASSERT] Zeilenga, K., "LDAP Assertion Control", draft-zeilenga-ldap-assert-xx.txt, a work in progress. 9. Informative References Zeilenga LDAP Read Entry Controls [Page 6] INTERNET-DRAFT draft-zeilenga-ldap-readentry-01 26 October 2003 [RFC3383] Zeilenga, K., "IANA Considerations for LDAP", BCP 64 (also RFC 3383), September 2002. [X.511] International Telecommunication Union - Telecommunication Standardization Sector, "The Directory: Abstract Service Definition", X.511(1993). [EntryUUID] Zeilenga, K., "The LDAP EntryUUID Operational Attribute", draft-zeilenga-ldap-uuid-xx.txt, a work in progress. 10. Author's Address Kurt D. Zeilenga OpenLDAP Foundation Intellectual Property Rights The IETF takes no position regarding the validity or scope of any intellectual property or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; neither does it represent that it has made any effort to identify any such rights. Information on the IETF's procedures with respect to rights in standards-track and standards-related documentation can be found in BCP-11. Copies of claims of rights made available for publication and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementors or users of this specification can be obtained from the IETF Secretariat. The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights which may cover technology that may be required to practice this standard. Please address the information to the IETF Executive Director. Full Copyright Copyright (C) The Internet Society (2003). All Rights Reserved. Zeilenga LDAP Read Entry Controls [Page 7] INTERNET-DRAFT draft-zeilenga-ldap-readentry-01 26 October 2003 This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it or assist in its implmentation may be prepared, copied, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. 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