7 INTERNET-DRAFT Kurt D. Zeilenga
8 Intended Category: Standard Track OpenLDAP Foundation
9 Expires in six months 17 May 2002
12 LDAP Cancel Extended Operation
13 <draft-zeilenga-ldap-cancel-05.txt>
16 1. Status of this Memo
18 This document is an Internet-Draft and is in full conformance with all
19 provisions of Section 10 of RFC2026.
21 This document is intended to be, after appropriate review and
22 revision, submitted to the RFC Editor as a Standard Track document.
23 Distribution of this memo is unlimited. Technical discussion of this
24 document will take place on the IETF LDAP Extension Working Group
25 mailing list <ietf-ldapext@netscape.com>. Please send editorial
26 comments directly to the author <Kurt@OpenLDAP.org>.
28 Internet-Drafts are working documents of the Internet Engineering Task
29 Force (IETF), its areas, and its working groups. Note that other
30 groups may also distribute working documents as Internet-Drafts.
31 Internet-Drafts are draft documents valid for a maximum of six months
32 and may be updated, replaced, or obsoleted by other documents at any
33 time. It is inappropriate to use Internet-Drafts as reference
34 material or to cite them other than as ``work in progress.''
36 The list of current Internet-Drafts can be accessed at
37 <http://www.ietf.org/ietf/1id-abstracts.txt>. The list of
38 Internet-Draft Shadow Directories can be accessed at
39 <http://www.ietf.org/shadow.html>.
41 Copyright 2002, The Internet Society. All Rights Reserved.
43 Please see the Copyright section near the end of this document for
49 This specification describes an LDAP (Lightweight Directory Access
50 Protocol) extended operation to cancel (or abandon) an outstanding
51 operation. Unlike the LDAP Abandon operation but like the X.511 DAP
52 Abandon operation, this operation has a response which provides an
53 indication of its outcome.
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65 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
66 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
67 document are to be interpreted as described in BCP 14 [RFC2119].
69 Protocol elements are described using ASN.1 [X.680]. The term
70 "BER-encoded" means the element is to be encoded using the Basic
71 Encoding Rules [X.690] under the restrictions detailed in Section 5.1
75 1. Background and Intent of Use
77 LDAP [RFC2251] provides an Abandon operation which clients may use to
78 cancel other operations. The Abandon operation does not have a
79 response and also calls for there to be no response of the abandoned
80 operation. These semantics provide the client with no clear
81 indication of the outcome of the Abandon operation.
83 X.511 DAP [X.511] provides an Abandon operation which does have a
84 response and also requires the abandoned operation to return a
85 response with indicating it was canceled. The Cancel operation is
86 modeled after the DAP Abandon operation.
88 The Cancel operation SHOULD be used instead of the LDAP Abandon
89 operation when the client needs an indication of the outcome. This
90 operation may be used to cancel both interrogation and update
96 The Cancel operation is defined as a LDAPv3 Extended Operation
97 [RFC2251, Section 4.12] identified by the OBJECT IDENTIFIER cancelOID.
98 This section details the syntax of the Cancel request and response
99 messages and defines additional LDAP resultCodes.
101 cancelOID OBJECT IDENTIFIER ::= IANA-ASSIGNED
103 cancelRequestValue ::= SEQUENCE {
110 The Cancel request is an ExtendedRequest with the requestName field
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119 containing cancelOID OID and a requestValue field which contains a
120 cancelRequestValue value encoded per [RFC2251, Section 5.1]. The
121 cancelID field contains the message id associated with the operation
127 A Cancel response is an ExtendedResponse where the responseName and
128 response fields are absent.
131 4.3. Additional Result Codes
133 Implementations of this specification SHALL recognize the following
134 additional resultCode values:
136 canceled (IANA-ASSIGNED-1)
137 noSuchOperation (IANA-ASSIGNED-2)
138 tooLate (IANA-ASSIGNED-3)
139 cannotCancel (IANA-ASSIGNED-4)
142 5. Operational Semantics
144 The function of the Cancel Operation is to request that the server
145 cancel an outstanding operation issued within the same session.
147 The client requests the cancelation of an outstanding operation by
148 issuing a Cancel Response with a cancelID with the message id
149 identifying the outstanding operation. The Cancel Request itself has
150 a distinct message id. Clients SHOULD NOT request cancelation of an
151 operation multiple times.
153 If the server is unable to parse the requestValue or the requestValue
154 is absent, the server shall return protocolError.
156 If the server is willing and able to cancel the outstanding operation
157 identified by the cancelId, the server SHALL return a Cancel Response
158 with a success resultCode and the canceled operation SHALL fail with
159 canceled resultCode. Otherwise the Cancel Response SHALL have a
160 non-success resultCode and SHALL NOT have impact upon the outstanding
161 operation (if it exists).
163 The server SHALL return noSuchOperation if it has no knowledge of the
164 operation requested to be canceled.
166 The server SHALL return cannotCancel if the identified operation does
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175 not support cancelation or the cancel operation could not be
176 performed. The following classes of operations are not cancelable:
178 - operations which have no response,
180 - operations which associate or disassociate authentication and/or
181 authorization associations,
183 - operations which establish or tear-down security services, and
185 - operations which abandon or cancel other operations.
187 Specifically, Abandon, Bind, Start TLS [RFC2830], Unbind and Cancel
188 operations are not cancelable.
190 If the result of the outstanding operation has been determined by the
191 server, the outstanding operation SHALL NOT be canceled and the cancel
192 operation SHALL result in tooLate.
194 Servers SHOULD indicate their support for this extended operation by
195 providing cancelOID as a value of the supportedExtension attribute
196 type in their root DSE. A server MAY choose to advertise this
197 extension only when the client is authorized and/or has established
198 the necessary security protections to use this operation. Clients
199 SHOULD verify the server implements this extended operation prior to
200 attempting the operation by asserting the supportedExtension attribute
201 contains a value of cancelOID.
204 6. Security Considerations
206 This operation is intended to allow a user to cancel operations they
207 previously issued. No user should be allowed to cancel an operation
208 issued by another user (within the same session or not). However, as
209 this operation may only be used to cancel within the same session and
210 LDAP requires operations to be abandoned upon bind requests, this is a
213 Some operations should not be cancelable for security reasons. This
214 specification disallows cancelation of Bind operation and Start TLS
215 extended operation so as to avoid adding complexity to authentication,
216 authorization, and security layer semantics. Designers of future
217 extended operations and/or controls SHOULD disallow abandonment and
218 cancelation when appropriate.
221 7. IANA Considerations
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231 7.1. Object Identifiers
233 It is requested that IANA register a Directory Number OID for use in
234 this document upon Standards Action by the IESG. This OID will be
235 used to identify the LDAP Cancel extended operation as indicated
236 above. The following registration template is suggested:
238 Subject: Request for LDAP OID Registration
239 Person & email address to contact for further information:
240 Kurt Zeilenga <kurt@OpenLDAP.org>
241 Specification: RFCXXX
242 Author/Change Controller: IESG
245 7.2. LDAP Result Codes
247 It is requested that IANA register the LDAP result codes:
249 canceled (IANA-ASSIGNED-1)
250 noSuchOperation (IANA-ASSIGNED-2)
251 tooLate (IANA-ASSIGNED-3)
252 cannotCancel (IANA-ASSIGNED-4)
254 upon Standards Action by the IESG. The following registration
255 template is suggested:
257 Subject: LDAP Result Code Registration
258 Person & email address to contact for further information:
259 Kurt Zeilenga <kurt@OpenLDAP.org>
260 Result Code Name: canceled
261 Result Code Name: noSuchOperation
262 Result Code Name: tooLate
263 Result Code Name: cannotCancel
264 Specification: RFCXXXX
265 Author/Change Controller: IESG
266 Comments: request four consecutive result codes be assigned
271 This document is based upon input from the IETF LDAPext working group.
274 9. Normative References
276 [RFC2119] S. Bradner, "Key words for use in RFCs to Indicate
277 Requirement Levels", BCP 14 (also RFC 2119), March 1997.
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284 INTERNET-DRAFT draft-zeilenga-ldap-cancel-05 17 May 2002
287 [RFC2251] M. Wahl, T. Howes, S. Kille, "Lightweight Directory Access
288 Protocol (v3)", RFC 2251, December 1997.
290 [RFC2830] J. Hodges, R. Morgan, and M. Wahl, "Lightweight Directory
291 Access Protocol (v3): Extension for Transport Layer
292 Security", RFC 2830, May 2000.
294 [X.680] ITU-T, "Abstract Syntax Notation One (ASN.1) - Specification
295 of Basic Notation", X.680, 1994.
297 [X.690] ITU-T, "Specification of ASN.1 encoding rules: Basic,
298 Canonical, and Distinguished Encoding Rules", X.690, 1994.
301 9. Informative References
303 [X.511] ITU-T Rec. X.511, "The Directory: Abstract Service
314 Copyright 2002, The Internet Society. All Rights Reserved.
316 This document and translations of it may be copied and furnished to
317 others, and derivative works that comment on or otherwise explain it
318 or assist in its implementation may be prepared, copied, published and
319 distributed, in whole or in part, without restriction of any kind,
320 provided that the above copyright notice and this paragraph are
321 included on all such copies and derivative works. However, this
322 document itself may not be modified in any way, such as by removing
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334 ENGINEERING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED,
338 Zeilenga LDAP Cancel [Page 6]
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343 INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
344 INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
345 WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
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