7 Network Working Group K. Zeilenga
8 Request for Comments: 3673 OpenLDAP Foundation
9 Category: Standards Track December 2003
12 Lightweight Directory Access Protocol version 3 (LDAPv3):
13 All Operational Attributes
17 This document specifies an Internet standards track protocol for the
18 Internet community, and requests discussion and suggestions for
19 improvements. Please refer to the current edition of the "Internet
20 Official Protocol Standards" (STD 1) for the standardization state
21 and status of this protocol. Distribution of this memo is unlimited.
25 Copyright (C) The Internet Society (2003). All Rights Reserved.
29 The Lightweight Directory Access Protocol (LDAP) supports a mechanism
30 for requesting the return of all user attributes but not all
31 operational attributes. This document describes an LDAP extension
32 which clients may use to request the return of all operational
37 X.500 [X.500] provides a mechanism for clients to request all
38 operational attributes be returned with entries provided in response
39 to a search operation. This mechanism is often used by clients to
40 discover which operational attributes are present in an entry.
42 This documents extends the Lightweight Directory Access Protocol
43 (LDAP) [RFC3377] to provide a simple mechanism which clients may use
44 to request the return of all operational attributes. The mechanism
45 is designed for use with existing general purpose LDAP clients
46 (including web browsers which support LDAP URLs) and existing LDAP
49 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
50 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
51 document are to be interpreted as described in BCP 14 [RFC2119].
58 Zeilenga Standards Track [Page 1]
60 RFC 3673 LDAPv3: All Operational Attributes December 2003
63 2. All Operational Attributes
65 The presence of the attribute description "+" (ASCII 43) in the list
66 of attributes in a Search Request [RFC2251] SHALL signify a request
67 for the return of all operational attributes.
69 As with all search requests, client implementors should note that
70 results may not include all requested attributes due to access
71 controls or other restrictions. Client implementors should also note
72 that certain operational attributes may be returned only if requested
73 by name even when "+" is present. This is because some operational
74 attributes are very expensive to return.
76 Servers supporting this feature SHOULD publish the Object Identifier
77 1.3.6.1.4.1.4203.1.5.1 as a value of the 'supportedFeatures'
78 [RFC3674] attribute in the root DSE.
80 3. Interoperability Considerations
82 This mechanism is specifically designed to allow users to request all
83 operational attributes using existing LDAP clients. In particular,
84 the mechanism is designed to be compatible with existing general
85 purpose LDAP clients including those supporting LDAP URLs [RFC2255].
87 The addition of this mechanism to LDAP is not believed to cause any
88 significant interoperability issues (this has been confirmed through
89 testing). Servers which have yet to implement this specification
90 should ignore the "+" as an unrecognized attribute description per
91 [RFC2251, Section 4.5.1]. From the client's perspective, a server
92 which does not return all operational attributes when "+" is
93 requested should be viewed as having other restrictions.
95 It is also noted that this mechanism is believed to require no
96 modification of existing LDAP APIs.
98 4. Security Considerations
100 This document provides a general mechanism which clients may use to
101 discover operational attributes. Prior to the introduction of this
102 mechanism, operational attributes were only returned when requested
103 by name. Some might have viewed this as obscurity feature. However,
104 this feature offers a false sense of security as the attributes were
107 Implementations SHOULD implement appropriate access controls
108 mechanisms to restricts access to operational attributes.
114 Zeilenga Standards Track [Page 2]
116 RFC 3673 LDAPv3: All Operational Attributes December 2003
119 5. IANA Considerations
121 This document uses the OID 1.3.6.1.4.1.4203.1.5.1 to identify the
122 feature described above. This OID was assigned [ASSIGN] by OpenLDAP
123 Foundation, under its IANA-assigned private enterprise allocation
124 [PRIVATE], for use in this specification.
126 Registration of this feature has been completed by IANA [RFC3674],
129 Subject: Request for LDAP Protocol Mechanism Registration
131 Object Identifier: 1.3.6.1.4.1.4203.1.5.1
133 Description: All Op Attrs
135 Person & email address to contact for further information:
136 Kurt Zeilenga <kurt@openldap.org>
140 Specification: RFC3673
142 Author/Change Controller: IESG
148 The "+" mechanism is believed to have been first suggested by Bruce
149 Greenblatt in a November 1998 post to the IETF LDAPext Working Group
152 7. Intellectual Property Statement
154 The IETF takes no position regarding the validity or scope of any
155 intellectual property or other rights that might be claimed to
156 pertain to the implementation or use of the technology described in
157 this document or the extent to which any license under such rights
158 might or might not be available; neither does it represent that it
159 has made any effort to identify any such rights. Information on the
160 IETF's procedures with respect to rights in standards-track and
161 standards-related documentation can be found in BCP-11. Copies of
162 claims of rights made available for publication and any assurances of
163 licenses to be made available, or the result of an attempt made to
164 obtain a general license or permission for the use of such
165 proprietary rights by implementors or users of this specification can
166 be obtained from the IETF Secretariat.
170 Zeilenga Standards Track [Page 3]
172 RFC 3673 LDAPv3: All Operational Attributes December 2003
175 The IETF invites any interested party to bring to its attention any
176 copyrights, patents or patent applications, or other proprietary
177 rights which may cover technology that may be required to practice
178 this standard. Please address the information to the IETF Executive
183 8.1. Normative References
185 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
186 Requirement Levels", BCP 14, RFC 2119, March 1997.
188 [RFC2251] Wahl, M., Howes, T. and S. Kille, "Lightweight Directory
189 Access Protocol (v3)", RFC 2251, December 1997.
191 [RFC3377] Hodges, J. and R. Morgan, "Lightweight Directory Access
192 Protocol (v3): Technical Specification", RFC 3377,
195 [RFC3674] Zeilenga, K., "Feature Discovery in Lightweight Directory
196 Access Protocol (LDAP)", RFC 3674, December 2003.
198 8.2. Informative References
200 [RFC2255] Howes, T. and M. Smith, "The LDAP URL Format", RFC 2255,
203 [RFC3383] Zeilenga, K., "Internet Assigned Numbers Authority (IANA)
204 Considerations for the Lightweight Directory Access
205 Protocol (LDAP)", BCP 64, RFC 3383, September 2002.
207 [X.500] ITU-T Rec. X.500, "The Directory: Overview of Concepts,
208 Models and Service", 1993.
210 [ASSIGN] OpenLDAP Foundation, "OpenLDAP OID Delegations",
211 http://www.openldap.org/foundation/oid-delegate.txt.
213 [PRIVATE] IANA, "Private Enterprise Numbers",
214 http://www.iana.org/assignments/enterprise-numbers.
221 EMail: Kurt@OpenLDAP.org
226 Zeilenga Standards Track [Page 4]
228 RFC 3673 LDAPv3: All Operational Attributes December 2003
231 10. Full Copyright Statement
233 Copyright (C) The Internet Society (2003). All Rights Reserved.
235 This document and translations of it may be copied and furnished to
236 others, and derivative works that comment on or otherwise explain it
237 or assist in its implementation may be prepared, copied, published
238 and distributed, in whole or in part, without restriction of any
239 kind, provided that the above copyright notice and this paragraph are
240 included on all such copies and derivative works. However, this
241 document itself may not be modified in any way, such as by removing
242 the copyright notice or references to the Internet Society or other
243 Internet organizations, except as needed for the purpose of
244 developing Internet standards in which case the procedures for
245 copyrights defined in the Internet Standards process must be
246 followed, or as required to translate it into languages other than
249 The limited permissions granted above are perpetual and will not be
250 revoked by the Internet Society or its successors or assignees.
252 This document and the information contained herein is provided on an
253 "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
254 TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
255 BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
256 HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
257 MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
261 Funding for the RFC Editor function is currently provided by the
282 Zeilenga Standards Track [Page 5]