INTERNET-DRAFT Kurt D. Zeilenga Intended Category: Informational OpenLDAP Foundation Expires in six months 18 July 2004 Requesting Attributes by Object Class in the Lightweight Directory Access Protocol Status of this Memo This document is intended to be, after appropriate review and revision, submitted to the RFC Editor as an Informational 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 . By submitting this Internet-Draft, I accept the provisions of Section 4 of RFC 3667. By submitting this Internet-Draft, I certify that any applicable patent or other IPR claims of which I am aware have been disclosed, or will be disclosed, and any of which I become aware will be disclosed, in accordance with RFC 3668. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet-Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at . The list of Internet-Draft Shadow Directories can be accessed at . Copyright (C) The Internet Society (2004). All Rights Reserved. Please see the Full Copyright section near the end of this document for more information. Abstract The Lightweight Directory Access Protocol (LDAP) search operation Zeilenga Requesting Attributes by Object Class [Page 1] INTERNET-DRAFT draft-zeilenga-ldap-adlist-08 18 July 2004 provides mechanisms for clients to request all user application attributes, all operational attributes, and/or attributes selected by their description. This document extends LDAP to support a mechanism that LDAP clients may use to request the return of all attributes belonging to an object class. 1. Overview In the Lightweight Directory Access Protocol (LDAP) [RFC3377], the search operation [RFC2251] support requesting a sets of attributes. This set is determined by a list of attribute descriptions. Two special descriptors are defined to request all user attributes ("*") [RFC2251] and all operational attributes ("+") [RFC3673]. However, there is no convenient mechanism for requesting pre-defined sets of attributes. This document extends LDAP to allow an object class identifier to be specified in attributes lists, such as in Search requests, to request the return all attributes belonging to an object class. The COMMERCIAL AT ("@", U+0040) character is used to distinguish an object class identifier from an attribute descriptions. For example, the attribute list of "@country" is equivalent to the attribute list of 'c', 'searchGuide', 'description', and 'objectClass'. This object class and its attributes are described in [RFC2256]. This extension is intended to be used where the user is in direct control of the parameters of the LDAP search operation, such as when entering a LDAP URL [RFC2255] into a web browser. 2. Terminology 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]. DSA stands for Directory System Agent (or server). DSE stands for DSA-specific Entry. 3. Return of all Attributes of an Object Class This extension allows object class identifiers is to be provided in the attributes field of the LDAP SearchRequest [RFC2251] or other request structures who borrow the attributes field and its semantics Zeilenga Requesting Attributes by Object Class [Page 2] INTERNET-DRAFT draft-zeilenga-ldap-adlist-08 18 July 2004 (e.g., attributes field in pre/post read controls [READENTRY]). For each object class identified in the attributes field, the request is to be treated as if each attribute allowed by that class (by "MUST" or "MAY", directly or by "SUP"erior) was itself listed. If the object class identifier is unrecognized, it is be treated an an unrecognized attribute description. This extension redefines the attributes field of the SearchRequest to be a DescriptionList described by the following ASN.1 [X.680] data type: DescriptionList ::= SEQUENCE OF Description Description ::= LDAPString The Description is string conforming to the ABNF [RFC2234]: Description = AttributeDescription | ObjectClassDescription. ObjectClassDescription = AtSign ObjectClass *( ";" options ) AtSign = "@" ; U+0040 where and productions are as defined in Section 4.1.5 of [RFC2251] and an is an object identifier, in either or form [RFC2252], of an object class. are provided for extensibility. This document only defines semantics of s with zero options in the attributes field of a SearchRequest. Other uses may be defined in future specifications. Servers supporting this feature SHOULD publish the object identifier (OID) IANA-ASSIGNED-OID as a value of the 'supportedFeatures' [RFC3674] attribute in the root DSE. Clients supporting this feature SHOULD NOT use the feature unless they have knowledge the server supports it. 3. Security Considerations This extension provides a shorthand for requesting all attributes of an object class. As these attributes which could have been listed individually, this shorthand is not believed to raise additional security considerations. Implementors of this (or any) LDAP extension should be familiar with general LDAP security considerations [RFC3377]. Zeilenga Requesting Attributes by Object Class [Page 3] INTERNET-DRAFT draft-zeilenga-ldap-adlist-08 18 July 2004 4. IANA Considerations Registration of the LDAP Protocol Mechanism [RFC3383] defined in document is requested. Subject: Request for LDAP Protocol Mechanism Registration Object Identifier: 1.3.6.1.4.1.4203.1.5.2 Description: OC AD Lists Person & email address to contact for further information: Kurt Zeilenga Usage: Feature Specification: RFC XXXX Author/Change Controller: Kurt Zeilenga Comments: none This OID was assigned [ASSIGN] by OpenLDAP Foundation, under its IANA-assigned private enterprise allocation [PRIVATE], for use in this specification. 5. Author's Address Kurt D. Zeilenga OpenLDAP Foundation Email: Kurt@OpenLDAP.org 6. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14 (also RFC 2119), March 1997. [RFC2234] Crocker, D. and P. Overell, "Augmented BNF for Syntax Specifications: ABNF", RFC 2234, November 1997. [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. [RFC3377] Hodges, J. and R. Morgan, "Lightweight Directory Access Protocol (v3): Technical Specification", RFC 3377, September 2002. [Features] Zeilenga, K., "Feature Discovery in LDAP", RFC 3674, Zeilenga Requesting Attributes by Object Class [Page 4] INTERNET-DRAFT draft-zeilenga-ldap-adlist-08 18 July 2004 December 2003. [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). 7. Informative References [RFC2255] Howes, T. and M. Smith, "The LDAP URL Format", RFC 2255, December, 1997. [RFC2256] Wahl, M., "A Summary of the X.500(96) User Schema for use with LDAPv3", RFC 2256, December 1997. [RFC3383] Zeilenga, K., "IANA Considerations for LDAP", BCP 64 (also RFC 3383), September 2002. [RFC3673] Zeilenga, K., "LDAPv3: All Operational Attributes", RFC 3673, December 2003. [READENTRY] Zeilenga, K., "LDAP Read Entry Controls", draft-zeilenga-ldap-readentry-xx.txt, a work in progress. [ASSIGN] OpenLDAP Foundation, "OpenLDAP OID Delegations", http://www.openldap.org/foundation/oid-delegate.txt. [PRIVATE] IANA, "Private Enterprise Numbers", http://www.iana.org/assignments/enterprise-numbers. Full Copyright Copyright (C) The Internet Society (2004). This document is subject to the rights, licenses and restrictions contained in BCP 78, and except as set forth therein, the authors retain all their rights. This document and the information contained herein are provided on an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Zeilenga Requesting Attributes by Object Class [Page 5] INTERNET-DRAFT draft-zeilenga-ldap-adlist-08 18 July 2004 Intellectual Property Rights The IETF takes no position regarding the validity or scope of any Intellectual Property Rights or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; nor does it represent that it has made any independent effort to identify any such rights. Information on the procedures with respect to rights in RFC documents can be found in BCP 78 and BCP 79. Copies of IPR disclosures made to the IETF Secretariat and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementers or users of this specification can be obtained from the IETF on-line IPR repository at http://www.ietf.org/ipr. The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights that may cover technology that may be required to implement this standard. Please address the information to the IETF at ietf-ipr@ietf.org. Zeilenga Requesting Attributes by Object Class [Page 6]