INTERNET-DRAFT Kurt D. Zeilenga Intended Category: Informational OpenLDAP Foundation Expires in six months 24 October 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. Zeilenga Requesting Attributes by Object Class [Page 1] INTERNET-DRAFT draft-zeilenga-ldap-adlist-09 24 October 2004 Abstract The Lightweight Directory Access Protocol (LDAP) search operation 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. Background and Intended Use In the Lightweight Directory Access Protocol (LDAP) [Roadmap], the search operation [Protocol] support requesting the return of a set of attributes. This set is determined by a list of attribute descriptions. Two special descriptors are defined to request all user attributes ("*") [Protocol] and all operational attributes ("+") [RFC3673]. However, there is no convenient mechanism for requesting pre-defined sets of attributes such as the set of attributes used to represent a particular class of object. 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 is described in [Schema]. This extension is intended primarily 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 [LDAPURL] 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 Zeilenga Requesting Attributes by Object Class [Page 2] INTERNET-DRAFT draft-zeilenga-ldap-adlist-09 24 October 2004 This extension allows object class identifiers is to be provided in the attributes field of the LDAP SearchRequest [Protocol] or other request values of the AttributeSelection data type (e.g., attributes field in pre/post read controls [ReadEntry]) and/or production (e.g., attributes of an LDAP URL [LDAPURL]). 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) [Models] was itself listed. This extension extends attributeSelector [Protocol] production as indicated by the following ABNF [RFC2234]: attributeSelector /= objectclassdescription objectclassdescription = ATSIGN oid options ATSIGN = %x40 ; COMMERCIAL AT ("@" U+0040) where and productions are as defined in [Models]. The component of an production identifies the object class by short name (descr) or object identifier (numericoid). If the value of the component is unrecognized or does not refer to an object class, the object class description is be treated an an unrecognized attribute description. The production is included in the grammar for extensibility purposes. An object class description with an unrecognized or inappropriate option is to be treated as an unrecognized. While object class description options and attribute description options share the same syntax, they are not semantically related. This document does not define any object description option. 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, introduction of this shorthand is not believed to raise additional security considerations. Implementors of this LDAP extension should be familiar with security Zeilenga Requesting Attributes by Object Class [Page 3] INTERNET-DRAFT draft-zeilenga-ldap-adlist-09 24 October 2004 considerations applicable to the LDAP search operation [Protocol], as well as general LDAP security considerations [Roadmap]. 4. IANA Considerations Registration of the LDAP Protocol Mechanism [BCP64bis] 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. References [[Note to the RFC Editor: please replace the citation tags used in referencing Internet-Drafts with tags of the form RFCnnnn where possible.]] 6.1. 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. [Features] Zeilenga, K., "Feature Discovery in LDAP", RFC 3674, Zeilenga Requesting Attributes by Object Class [Page 4] INTERNET-DRAFT draft-zeilenga-ldap-adlist-09 24 October 2004 December 2003. [Roadmap] Zeilenga, K. (editor), "LDAP: Technical Specification Road Map", draft-ietf-ldapbis-roadmap-xx.txt, a work in progress. [Protocol] Sermersheim, J. (editor), "LDAP: The Protocol", draft-ietf-ldapbis-protocol-xx.txt, a work in progress. [Models] Zeilenga, K. (editor), "LDAP: Directory Information Models", draft-ietf-ldapbis-models-xx.txt, a work in progress. [LDAPURL] Smith, M. (editor), "LDAP: Uniform Resource Locator", draft-ietf-ldapbis-url-xx.txt, a work in progress. [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). 6.2. Informative References [RFC3673] Zeilenga, K., "LDAPv3: All Operational Attributes", RFC 3673, December 2003. [Schema] Dally, K. (editor), "LDAP: User Schema", draft-ietf-ldapbis-user-schema-xx.txt, a work in progress. [BCP64bis] Zeilenga, K., "IANA Considerations for LDAP", draft-ietf-ldapbis-bcp64-xx.txt, a work in progress. [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 Zeilenga Requesting Attributes by Object Class [Page 5] INTERNET-DRAFT draft-zeilenga-ldap-adlist-09 24 October 2004 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. 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