1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
|
<pre>Network Working Group K. Zeilenga
Request for Comments: 4527 OpenLDAP Foundation
Category: Standards Track June 2006
<span class="h1">Lightweight Directory Access Protocol (LDAP)</span>
<span class="h1">Read Entry Controls</span>
Status of This Memo
This document specifies an Internet standards track protocol for the
Internet community, and requests discussion and suggestions for
improvements. Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (2006).
Abstract
This document specifies an extension to the Lightweight Directory
Access Protocol (LDAP) to allow the client to read the target entry
of an update operation. The client may request to read the entry
before and/or after the modifications are applied. These reads are
done as an atomic part of the update operation.
Table of Contents
<a href="#section-1">1</a>. Background and Intent of Use ....................................<a href="#page-2">2</a>
<a href="#section-2">2</a>. Terminology .....................................................<a href="#page-2">2</a>
<a href="#section-3">3</a>. Read Entry Controls .............................................<a href="#page-3">3</a>
<a href="#section-3.1">3.1</a>. The Pre-Read Controls ......................................<a href="#page-3">3</a>
<a href="#section-3.2">3.2</a>. The Post-Read Controls .....................................<a href="#page-3">3</a>
<a href="#section-4">4</a>. Interaction with Other Controls .................................<a href="#page-4">4</a>
<a href="#section-5">5</a>. Security Considerations .........................................<a href="#page-4">4</a>
<a href="#section-6">6</a>. IANA Considerations .............................................<a href="#page-5">5</a>
<a href="#section-6.1">6.1</a>. Object Identifier ..........................................<a href="#page-5">5</a>
<a href="#section-6.2">6.2</a>. LDAP Protocol Mechanisms ...................................<a href="#page-5">5</a>
<a href="#section-7">7</a>. Acknowledgement .................................................<a href="#page-5">5</a>
<a href="#section-8">8</a>. References ......................................................<a href="#page-6">6</a>
<a href="#section-8.1">8.1</a>. Normative References .......................................<a href="#page-6">6</a>
<a href="#section-8.2">8.2</a>. Informative References .....................................<a href="#page-7">7</a>
<span class="grey">Zeilenga Standards Track [Page 1]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-2" ></span>
<span class="grey"><a href="./rfc4527">RFC 4527</a> LDAP Read Entry Controls June 2006</span>
<span class="h2"><a class="selflink" id="section-1" href="#section-1">1</a>. Background and Intent of Use</span>
This document specifies an extension to the Lightweight Directory
Access Protocol (LDAP) [<a href="./rfc4510" title=""Lightweight Directory Access Protocol (LDAP): Technical Specification Road Map"">RFC4510</a>] to allow the client to read the
target entry of an update operation (e.g., Add, Delete, Modify,
ModifyDN). The extension utilizes controls [<a href="./rfc4511" title=""Lightweight Directory Access Protocol (LDAP): The Protocol"">RFC4511</a>] attached to
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.
To ensure proper isolation, the controls are processed as an atomic
part of the update operation.
The functionality offered by these controls is based upon similar
functionality in the X.500 Directory Access Protocol (DAP) [<a href="#ref-X.511" title=""The Directory: Abstract Service Definition"">X.511</a>].
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' [<a href="./rfc4530" title=""Lightweight Directory Access Protocol (LDAP) EntryUUID Operational Attribute"">RFC4530</a>] and 'modifyTimestamp'
[<a href="./rfc4512" title=""Lightweight Directory Access Protocol (LDAP): Directory Information Models"">RFC4512</a>] attributes, updated by the server as part of the update
operation.
<span class="h2"><a class="selflink" id="section-2" href="#section-2">2</a>. Terminology</span>
Protocol elements are described using ASN.1 [<a href="#ref-X.680" title=""Abstract Syntax Notation One (ASN.1) - Specification of Basic Notation"">X.680</a>] with implicit
tags. The term "BER-encoded" means the element is to be encoded
using the Basic Encoding Rules [<a href="#ref-X.690" title=""Specification of ASN.1 encoding rules: Basic Encoding Rules (BER), Canonical Encoding Rules (CER), and Distinguished Encoding Rules (DER)"">X.690</a>] under the restrictions
detailed in <a href="./rfc4511#section-5.1">Section 5.1 of [RFC4511]</a>.
DN stands for Distinguished Name.
DSA stands for Directory System Agent (i.e., a directory server).
DSE stands for DSA-specific Entry.
In this document, the key words "MUST", "MUST NOT", "REQUIRED",
"SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY",
and "OPTIONAL" are to be interpreted as described in <a href="https://www.rfc-editor.org/bcp/bcp14">BCP 14</a>
[<a href="./rfc2119" title=""Key words for use in RFCs to Indicate Requirement Levels"">RFC2119</a>].
<span class="grey">Zeilenga Standards Track [Page 2]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-3" ></span>
<span class="grey"><a href="./rfc4527">RFC 4527</a> LDAP Read Entry Controls June 2006</span>
<span class="h2"><a class="selflink" id="section-3" href="#section-3">3</a>. Read Entry Controls</span>
<span class="h3"><a class="selflink" id="section-3.1" href="#section-3.1">3.1</a>. The Pre-Read Controls</span>
The Pre-Read request and response controls are identified by the
1.3.6.1.1.13.1 object identifier. Servers implementing these
controls SHOULD publish 1.3.6.1.1.13.1 as a value of the
'supportedControl' [<a href="./rfc4512" title=""Lightweight Directory Access Protocol (LDAP): Directory Information Models"">RFC4512</a>] in their root DSE.
The Pre-Read request control is a LDAP Control [<a href="./rfc4511" title=""Lightweight Directory Access Protocol (LDAP): The Protocol"">RFC4511</a>] whose
controlType is 1.3.6.1.1.13.1 and whose controlValue is a BER-encoded
AttributeSelection [<a href="./rfc4511" title=""Lightweight Directory Access Protocol (LDAP): The Protocol"">RFC4511</a>], as extended by [<a href="./rfc3673" title=""Lightweight Directory Access Protocol version 3 (LDAPv3): All Operational Attributes"">RFC3673</a>]. 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 1.3.6.1.1.13.1 and whose 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 the target
entry prior to the application of the update. The AttributeSelection
indicates, as discussed in [<a href="./rfc4511" title=""Lightweight Directory Access Protocol (LDAP): The Protocol"">RFC4511</a>][RFC3673], which attributes are
requested to appear in the copy. 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 (in either normal or control
processing), no Pre-Read response control is provided.
<span class="h3"><a class="selflink" id="section-3.2" href="#section-3.2">3.2</a>. The Post-Read Controls</span>
The Post-Read request and response controls are identified by the
1.3.6.1.1.13.2 object identifier. Servers implementing these
controls SHOULD publish 1.3.6.1.1.13.2 as a value of the
'supportedControl' [<a href="./rfc4512" title=""Lightweight Directory Access Protocol (LDAP): Directory Information Models"">RFC4512</a>] in their root DSE.
The Post-Read request control is a LDAP Control [<a href="./rfc4511" title=""Lightweight Directory Access Protocol (LDAP): The Protocol"">RFC4511</a>] whose
controlType is 1.3.6.1.1.13.2 and whose controlValue, an OCTET
STRING, contains a BER-encoded AttributeSelection [<a href="./rfc4511" title=""Lightweight Directory Access Protocol (LDAP): The Protocol"">RFC4511</a>], as
extended by [<a href="./rfc3673" title=""Lightweight Directory Access Protocol version 3 (LDAPv3): All Operational Attributes"">RFC3673</a>]. The criticality may be TRUE or FALSE. This
<span class="grey">Zeilenga Standards Track [Page 3]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-4" ></span>
<span class="grey"><a href="./rfc4527">RFC 4527</a> LDAP Read Entry Controls June 2006</span>
control is appropriate for the addRequest, modifyRequest, and
modDNRequest LDAP messages.
The corresponding response control is a LDAP Control whose
controlType is 1.3.6.1.1.13.2 and whose controlValue is a BER-encoded
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 the target
entry after the application of the update. The AttributeSelection
indicates, as discussed in [<a href="./rfc4511" title=""Lightweight Directory Access Protocol (LDAP): The Protocol"">RFC4511</a>][RFC3673], which attributes are
requested to appear in the copy. 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 (in either normal or control
processing), no Post-Read response control is provided.
<span class="h2"><a class="selflink" id="section-4" href="#section-4">4</a>. Interaction with Other Controls</span>
The Pre-Read and Post-Read controls may be combined with each other
and/or with a variety of other controls. When combined with the
assertion control [<a href="./rfc4528" title=""Lightweight Directory Access Protocol (LDAP) Assertion Control"">RFC4528</a>] and/or the manageDsaIT control [<a href="./rfc3296" title=""Named Subordinate References in Lightweight Directory Access Protocol (LDAP) Directories"">RFC3296</a>],
the semantics of each control included in the combination applies.
The Pre-Read and Post-Read controls may be combined with other
controls as detailed in other technical specifications.
<span class="h2"><a class="selflink" id="section-5" href="#section-5">5</a>. Security Considerations</span>
The controls defined in this document extend update operations to
support read capabilities. Servers MUST ensure that the client is
authorized for reading of the information provided in this control
and that the client is authorized to perform the requested directory
update.
Security considerations for the update operations [<a href="./rfc4511" title=""Lightweight Directory Access Protocol (LDAP): The Protocol"">RFC4511</a>] extended
by this control, as well as general LDAP security considerations
[<a href="./rfc4510" title=""Lightweight Directory Access Protocol (LDAP): Technical Specification Road Map"">RFC4510</a>], generally apply to implementation and use of this
extension
<span class="grey">Zeilenga Standards Track [Page 4]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-5" ></span>
<span class="grey"><a href="./rfc4527">RFC 4527</a> LDAP Read Entry Controls June 2006</span>
<span class="h2"><a class="selflink" id="section-6" href="#section-6">6</a>. IANA Considerations</span>
Registration of the following protocol values [<a href="./rfc4520" title=""Internet Assigned Numbers Authority (IANA) Considerations for the Lightweight Directory Access Protocol (LDAP)"">RFC4520</a>] have been
completed by the IANA.
<span class="h3"><a class="selflink" id="section-6.1" href="#section-6.1">6.1</a>. Object Identifier</span>
The IANA has registered 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 <kurt@OpenLDAP.org>
Specification: <a href="./rfc4527">RFC 4527</a>
Author/Change Controller: IESG
Comments: Identifies the LDAP Read Entry Controls
<span class="h3"><a class="selflink" id="section-6.2" href="#section-6.2">6.2</a>. LDAP Protocol Mechanisms</span>
The IANA has registered the LDAP Protocol Mechanism described in this
document.
Subject: Request for LDAP Protocol Mechanism Registration
Object Identifier: 1.3.6.1.1.13.1
Description: LDAP Pre-read Control
Person & email address to contact for further information:
Kurt Zeilenga <kurt@openldap.org>
Usage: Control
Specification: <a href="./rfc4527">RFC 4527</a>
Author/Change Controller: IESG
Comments: none
Subject: Request for LDAP Protocol Mechanism Registration
Object Identifier: 1.3.6.1.1.13.2
Description: LDAP Post-read Control
Person & email address to contact for further information:
Kurt Zeilenga <kurt@openldap.org>
Usage: Control
Specification: <a href="./rfc4527">RFC 4527</a>
Author/Change Controller: IESG
Comments: none
<span class="h2"><a class="selflink" id="section-7" href="#section-7">7</a>. Acknowledgement</span>
The LDAP Pre-Read and Post-Read controls are modeled after similar
capabilities offered in the DAP [<a href="#ref-X.511" title=""The Directory: Abstract Service Definition"">X.511</a>].
<span class="grey">Zeilenga Standards Track [Page 5]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-6" ></span>
<span class="grey"><a href="./rfc4527">RFC 4527</a> LDAP Read Entry Controls June 2006</span>
<span class="h2"><a class="selflink" id="section-8" href="#section-8">8</a>. References</span>
<span class="h3"><a class="selflink" id="section-8.1" href="#section-8.1">8.1</a>. Normative References</span>
[<a id="ref-RFC2119">RFC2119</a>] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", <a href="https://www.rfc-editor.org/bcp/bcp14">BCP 14</a>, <a href="./rfc2119">RFC 2119</a>, March 1997.
[<a id="ref-RFC3296">RFC3296</a>] Zeilenga, K., "Named Subordinate References in
Lightweight Directory Access Protocol (LDAP)
Directories", <a href="./rfc3296">RFC 3296</a>, July 2002.
[<a id="ref-RFC3673">RFC3673</a>] Zeilenga, K., "Lightweight Directory Access Protocol
version 3 (LDAPv3): All Operational Attributes", <a href="./rfc3673">RFC</a>
<a href="./rfc3673">3673</a>, December 2003.
[<a id="ref-RFC4510">RFC4510</a>] Zeilenga, K., Ed, "Lightweight Directory Access
Protocol (LDAP): Technical Specification Road Map", <a href="./rfc4510">RFC</a>
<a href="./rfc4510">4510</a>, June 2006.
[<a id="ref-RFC4511">RFC4511</a>] Sermersheim, J., Ed., "Lightweight Directory Access
Protocol (LDAP): The Protocol", <a href="./rfc4511">RFC 4511</a>, June 2006.
[<a id="ref-RFC4512">RFC4512</a>] Zeilenga, K., "Lightweight Directory Access Protocol
(LDAP): Directory Information Models", <a href="./rfc4512">RFC 4512</a>, June
2006.
[<a id="ref-RFC4528">RFC4528</a>] Zeilenga, K., "Lightweight Directory Access Protocol
(LDAP) Assertion Control", <a href="./rfc4528">RFC 4528</a>, June 2006.
[<a id="ref-X.680">X.680</a>] 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).
[<a id="ref-X.690">X.690</a>] 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).
<span class="grey">Zeilenga Standards Track [Page 6]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-7" ></span>
<span class="grey"><a href="./rfc4527">RFC 4527</a> LDAP Read Entry Controls June 2006</span>
<span class="h3"><a class="selflink" id="section-8.2" href="#section-8.2">8.2</a>. Informative References</span>
[<a id="ref-RFC4520">RFC4520</a>] Zeilenga, K., "Internet Assigned Numbers Authority
(IANA) Considerations for the Lightweight Directory
Access Protocol (LDAP)", <a href="https://www.rfc-editor.org/bcp/bcp64">BCP 64</a>, <a href="./rfc4520">RFC 4520</a>, June 2006.
[<a id="ref-RFC4530">RFC4530</a>] Zeilenga, K., "Lightweight Directory Access Protocol
(LDAP) EntryUUID Operational Attribute", <a href="./rfc4530">RFC 4530</a>, June
2006.
[<a id="ref-X.511">X.511</a>] International Telecommunication Union -
Telecommunication Standardization Sector, "The
Directory: Abstract Service Definition", X.511(1993)
(also ISO/IEC 9594-3:1993).
Author's Address
Kurt D. Zeilenga
OpenLDAP Foundation
EMail: Kurt@OpenLDAP.org
<span class="grey">Zeilenga Standards Track [Page 7]</span></pre>
<hr class='noprint'/><!--NewPage--><pre class='newpage'><span id="page-8" ></span>
<span class="grey"><a href="./rfc4527">RFC 4527</a> LDAP Read Entry Controls June 2006</span>
Full Copyright Statement
Copyright (C) The Internet Society (2006).
This document is subject to the rights, licenses and restrictions
contained in <a href="https://www.rfc-editor.org/bcp/bcp78">BCP 78</a>, 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.
Intellectual Property
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 <a href="https://www.rfc-editor.org/bcp/bcp78">BCP 78</a> and <a href="https://www.rfc-editor.org/bcp/bcp79">BCP 79</a>.
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
<a href="http://www.ietf.org/ipr">http://www.ietf.org/ipr</a>.
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.
Acknowledgement
Funding for the RFC Editor function is provided by the IETF
Administrative Support Activity (IASA).
Zeilenga Standards Track [Page 8]
</pre>
|
