xref: /netbsd-src/external/bsd/openldap/dist/doc/drafts/draft-behera-ldap-password-policy-xx.txt (revision e670fd5c413e99c2f6a37901bb21c537fcd322d2)
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4Network Working Group                                     J. Sermersheim
5Internet-Draft                                               Novell, Inc
6Intended status: Standards Track                               L. Poitou
7Expires: January 19, 2015                               Sun Microsystems
8                                                             H. Chu, Ed.
9                                                             Symas Corp.
10                                                           July 18, 2014
11
12
13                  Password Policy for LDAP Directories
14                  draft-behera-ldap-password-policy-11
15
16Abstract
17
18   Password policy as described in this document is a set of rules that
19   controls how passwords are used and administered in Lightweight
20   Directory Access Protocol (LDAP) based directories.  In order to
21   improve the security of LDAP directories and make it difficult for
22   password cracking programs to break into directories, it is desirable
23   to enforce a set of rules on password usage.  These rules are made to
24   ensure that users change their passwords periodically, passwords meet
25   construction requirements, the re-use of old password is restricted,
26   and to deter password guessing attacks.
27
28Status of this Memo
29
30   This Internet-Draft is submitted in full conformance with the
31   provisions of BCP 78 and BCP 79.
32
33   Internet-Drafts are working documents of the Internet Engineering
34   Task Force (IETF).  Note that other groups may also distribute
35   working documents as Internet-Drafts.  The list of current Internet-
36   Drafts is at http://datatracker.ietf.org/drafts/current/.
37
38   Internet-Drafts are draft documents valid for a maximum of six months
39   and may be updated, replaced, or obsoleted by other documents at any
40   time.  It is inappropriate to use Internet-Drafts as reference
41   material or to cite them other than as "work in progress."
42
43   This Internet-Draft will expire on January 19, 2015.
44
45Copyright Notice
46
47   Copyright (c) 2014 IETF Trust and the persons identified as the
48   document authors.  All rights reserved.
49
50   This document is subject to BCP 78 and the IETF Trust's Legal
51   Provisions Relating to IETF Documents
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60   (http://trustee.ietf.org/license-info) in effect on the date of
61   publication of this document.  Please review these documents
62   carefully, as they describe your rights and restrictions with respect
63   to this document.  Code Components extracted from this document must
64   include Simplified BSD License text as described in Section 4.e of
65   the Trust Legal Provisions and are provided without warranty as
66   described in the Simplified BSD License.
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116Table of Contents
117
118   1.    Overview . . . . . . . . . . . . . . . . . . . . . . . . . .  4
119   2.    Conventions  . . . . . . . . . . . . . . . . . . . . . . . .  5
120   3.    Application of Password Policy . . . . . . . . . . . . . . .  6
121   4.    Articles of Password Policy  . . . . . . . . . . . . . . . .  7
122   4.1.  Password Usage Policy  . . . . . . . . . . . . . . . . . . .  7
123   4.2.  Password Modification Policy . . . . . . . . . . . . . . . .  8
124   4.3.  Restriction of the Password Policy . . . . . . . . . . . . . 10
125   5.    Schema used for Password Policy  . . . . . . . . . . . . . . 12
126   5.1.  The pwdPolicy Object Class . . . . . . . . . . . . . . . . . 12
127   5.2.  Attribute Types used in the pwdPolicy ObjectClass  . . . . . 12
128   5.3.  Attribute Types for Password Policy State Information  . . . 19
129   6.    Controls used for Password Policy  . . . . . . . . . . . . . 24
130   6.1.  Request Control  . . . . . . . . . . . . . . . . . . . . . . 24
131   6.2.  Response Control . . . . . . . . . . . . . . . . . . . . . . 24
132   7.    Policy Decision Points . . . . . . . . . . . . . . . . . . . 26
133   7.1.  Locked Account Check . . . . . . . . . . . . . . . . . . . . 26
134   7.2.  Password Must be Changed Now Check . . . . . . . . . . . . . 26
135   7.3.  Password Expiration Check  . . . . . . . . . . . . . . . . . 27
136   7.4.  Remaining Grace AuthN Check  . . . . . . . . . . . . . . . . 27
137   7.5.  Time Before Expiration Check . . . . . . . . . . . . . . . . 27
138   7.6.  Intruder Lockout Check . . . . . . . . . . . . . . . . . . . 27
139   7.7.  Intruder Delay Check . . . . . . . . . . . . . . . . . . . . 28
140   7.8.  Password Too Young Check . . . . . . . . . . . . . . . . . . 28
141   8.    Server Policy Enforcement Points . . . . . . . . . . . . . . 29
142   8.1.  Password-based Authentication  . . . . . . . . . . . . . . . 29
143   8.2.  Password Update Operations . . . . . . . . . . . . . . . . . 31
144   8.3.  Other Operations . . . . . . . . . . . . . . . . . . . . . . 34
145   9.    Client Policy Enforcement Points . . . . . . . . . . . . . . 35
146   9.1.  Bind Operation . . . . . . . . . . . . . . . . . . . . . . . 35
147   9.2.  Modify Operations  . . . . . . . . . . . . . . . . . . . . . 36
148   9.3.  Add Operation  . . . . . . . . . . . . . . . . . . . . . . . 37
149   9.4.  Compare Operation  . . . . . . . . . . . . . . . . . . . . . 37
150   9.5.  Other Operations . . . . . . . . . . . . . . . . . . . . . . 38
151   10.   Administration of the Password Policy  . . . . . . . . . . . 39
152   11.   Password Policy and Replication  . . . . . . . . . . . . . . 40
153   12.   Security Considerations  . . . . . . . . . . . . . . . . . . 42
154   13.   IANA Considerations  . . . . . . . . . . . . . . . . . . . . 43
155   13.1. Object Identifiers . . . . . . . . . . . . . . . . . . . . . 43
156   13.2. LDAP Protocol Mechanisms . . . . . . . . . . . . . . . . . . 43
157   13.3. LDAP Descriptors . . . . . . . . . . . . . . . . . . . . . . 43
158   13.4. LDAP AttributeDescription Options  . . . . . . . . . . . . . 45
159   14.   Acknowledgement  . . . . . . . . . . . . . . . . . . . . . . 46
160   15.   Normative References . . . . . . . . . . . . . . . . . . . . 47
161         Authors' Addresses . . . . . . . . . . . . . . . . . . . . . 48
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1721.  Overview
173
174   LDAP-based directory services are currently accepted by many
175   organizations as the access protocol for directories.  The ability to
176   ensure the secure read and update access to directory information
177   throughout the network is essential to the successful deployment.
178   Most LDAP implementations support many authentication schemes - the
179   most basic and widely used is the simple authentication i.e., user DN
180   and password.  In this case, many LDAP servers have implemented some
181   kind of policy related to the password used to authenticate.  Among
182   other things, this policy includes:
183
184   o  Whether and when passwords expire.
185
186   o  Whether failed bind attempts cause the account to be locked.
187
188   o  If and how users are able to change their passwords.
189
190   In order to achieve greater security protection and ensure
191   interoperability in a heterogeneous environment, LDAP needs to
192   standardize on a common password policy model.  This is critical to
193   the successful deployment of LDAP directories.
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2282.  Conventions
229
230   Imperative keywords defined in [RFC2119] are used in this document,
231   and carry the meanings described there.
232
233   All ASN.1 [X.680] Basic Encoding Rules (BER) [X.690] encodings follow
234   the conventions found in Section 5.1 of [RFC4511].
235
236   The term "password administrator" refers to a user that has
237   sufficient access control privileges to modify users' passwords.  The
238   term "password policy administrator" refers to a user that has
239   sufficient access control privileges to modify the pwdPolicy object
240   defined in this document.  The access control that is used to
241   determine whether an identity is a password administrator or password
242   policy administrator is beyond the scope of this document, but
243   typically implies that the password administrator has 'write'
244   privileges to the password attribute.
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2843.  Application of Password Policy
285
286   The password policy defined in this document can be applied to any
287   attribute holding a user's password used for an authenticated LDAP
288   bind operation.  In this document, the term "user" represents any
289   LDAP client application that has an identity in the directory.
290
291   This policy is typically applied to the userPassword attribute in the
292   case of the LDAP simple authentication method [RFC4511] or the case
293   of password based SASL [RFC4422] authentication such as CRAM-MD5
294   [RFC2195] and DIGEST-MD5 [RFC2831].
295
296   The policy described in this document assumes that the password
297   attribute holds a single value.  No considerations are made for
298   directories or systems that allow a user to maintain multi-valued
299   password attributes.
300
301   Server implementations MAY institute internal policy whereby certain
302   identities (such as directory administrators) are not forced to
303   comply with any of password policy.  In this case, the password for a
304   directory administrator never expires; the account is never locked,
305   etc.
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3404.  Articles of Password Policy
341
342   The following sections explain in general terms each aspect of the
343   password policy defined in this document as well as the need for
344   each.  These policies are subdivided into the general groups of
345   password usage and password modification.  Implementation details are
346   presented in Section 8 and Section 9.
347
3484.1.  Password Usage Policy
349
350   This section describes policy enforced when a password is used to
351   authenticate.  The general focus of this policy is to minimize the
352   threat of intruders once a password is in use.
353
3544.1.1.  Password Validity Policy
355
356   These mechanisms allow account usage to be controlled independent of
357   any password expiration policies.  The policy defines the absolute
358   period of time for which an account may be used.  This allows an
359   administrator to define an absolute starting time after which a
360   password becomes valid, and an absolute ending time after which the
361   password is disabled.
362
363   A mechanism is also provided to define the period of time for which
364   an account may remain unused before being disabled.
365
3664.1.2.  Password Guessing Limit
367
368   In order to prevent intruders from guessing a user's password, a
369   mechanism exists to track the number of consecutive failed
370   authentication attempts, and take action when a limit is reached.
371   This policy consists of several parts:
372
373   o  A counter to track the number of failed authentication attempts.
374
375   o  The amount of time to delay on the first authentication failure.
376
377   o  The maximum amount of time to delay on subsequent failures.
378
379   o  A timeframe in which the limit of consecutive failed
380      authentication attempts must happen before action is taken.
381
382   o  A configurable limit on failed authentication attempts.
383
384   o  The action to be taken when the limit is reached.  The action will
385      either be nothing, or the account will be locked.
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396   o  An amount of time the account is locked (if it is to be locked).
397      This can be indefinite.
398
399   Note that using the account lock feature provides an easy avenue for
400   Denial-of-Service (DoS) attacks on user accounts.  While some sites'
401   policies require accounts to be locked, this feature is discouraged
402   in favor of delaying each failed login attempt.
403
404   The delay time will be doubled on each subsequent failure, until it
405   reaches the maximum time configured.
406
407   [TBD: we could also provide a syntax for configuring a backoff
408   algorithm.  E.g. "+<int>" for linearly incrementing delay, "x<int>"
409   for constant multiplier, "^<int> for geometric.  But it's probably
410   overkill to add a calculator language to the server.]
411
4124.2.  Password Modification Policy
413
414   This section describes policy enforced while users are modifying
415   passwords.  The general focus of this policy is to ensure that when
416   users add or change their passwords, the security and effectiveness
417   of their passwords is maximized.  In this document, the term "modify
418   password operation" refers to any operation that is used to add or
419   modify a password attribute.  Often this is done by updating the
420   password attribute during an add or modify operation, but MAY be done
421   by other means such as an extended operation.
422
4234.2.1.  Password Expiration, Expiration Warning, and Grace
424        Authentications
425
426   One of the key properties of a password is the fact that it is not
427   well known.  If a password is frequently changed, the chances of that
428   user's account being broken into are minimized.
429
430   Password policy administrators may deploy a password policy that
431   causes passwords to expire after a given amount of time - thus
432   forcing users to change their passwords periodically.
433
434   As a side effect, there needs to be a way in which users are made
435   aware of this need to change their password before actually being
436   locked out of their accounts.  One or both of the following methods
437   handle this:
438
439   o  A warning may be returned to the user sometime before his password
440      is due to expire.  If the user fails to heed this warning before
441      the expiration time, his account will be locked.
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452   o  The user may bind to the directory a preset number of times after
453      her password has expired.  If she fails to change her password
454      during one of her 'grace' authentications, her account will be
455      locked.
456
4574.2.2.  Password History
458
459   When the Password Expiration policy is used, an additional mechanism
460   may be employed to prevent users from simply re-using a previous
461   password (as this would effectively circumvent the expiration
462   policy).
463
464   In order to do this; a history of used passwords is kept.  The
465   password policy administrator sets the number of passwords to be
466   stored at any given time.  Passwords are stored in this history
467   whenever the password is changed.  Users aren't allowed to specify
468   any passwords that are in the history list while changing passwords.
469
4704.2.3.  Password Minimum Age
471
472   Users may circumvent the Password History mechanism by quickly
473   performing a series of password changes.  If they change their
474   password enough times, their 'favorite' password will be pushed out
475   of the history list.
476
477   This process may be made less attractive to users by employing a
478   minimum age for passwords.  If users are forced to wait 24 hours
479   between password changes, they may be less likely to cycle through a
480   history of 10 passwords.
481
4824.2.4.  Password Quality and Minimum length
483
484   In order to prevent users from creating or updating passwords that
485   are easy to guess, a password quality policy may be employed.  This
486   policy consists of two general mechanisms - ensuring that passwords
487   conform to a defined quality criterion and ensuring that they are of
488   a minimum length.
489
490   Forcing a password to comply with the quality policy may imply a
491   variety of things including:
492
493   o  Disallowing trivial or well-known words make up the password.
494
495   o  Forcing a certain number of digits be used.
496
497   o  Disallowing anagrams of the user's name.
498
499   The implementation of this policy meets with the following problems:
500
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508   o  If the password to be added or updated is encrypted by the client
509      before being sent, the server has no way of enforcing this policy.
510      Therefore, the onus of enforcing this policy falls upon client
511      implementations.
512
513   o  There are no specific definitions of what 'quality checking'
514      means.  This can lead to unexpected behavior in a heterogeneous
515      environment.
516
5174.2.5.  User Defined Passwords
518
519   In some cases, it is desirable to disallow users from adding and
520   updating their own passwords.  This policy makes this functionality
521   possible.
522
5234.2.6.  Password Change after Reset
524
525   This policy forces the user to update her password after it has been
526   set for the first time, or has been reset by a password
527   administrator.
528
529   This is needed in scenarios where a password administrator has set or
530   reset the password to a well-known value.
531
5324.2.7.  Safe Modification
533
534   As directories become more commonly used, it will not be unusual for
535   clients to connect to a directory and leave the connection open for
536   an extended period.  This opens up the possibility for an intruder to
537   make modifications to a user's password while that user's computer is
538   connected but unattended.
539
540   This policy forces the user to prove his identity by specifying the
541   old password during a password modify operation.
542
543   {TODO: This allows a dictionary attack unless we specify that this is
544   also subject to intruder detection.  One solution is to require users
545   to authN prior to changing password.  Another solution is to perform
546   intruder detection checks when the password for a non-authenticated
547   identity is being updated}
548
5494.3.  Restriction of the Password Policy
550
551   The password policy defined in this document can apply to any
552   attribute containing a password.  Password policy state information
553   is held in the user's entry, and applies to a password attribute, not
554   a particular password attribute value.  Thus the server SHOULD
555   enforce that the password attribute subject to password policy,
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6205.  Schema used for Password Policy
621
622   The schema elements defined here fall into two general categories.  A
623   password policy object class is defined which contains a set of
624   administrative password policy attributes, and a set of operational
625   attributes are defined that hold general password policy state
626   information for each user.
627
6285.1.  The pwdPolicy Object Class
629
630   This object class contains the attributes defining a password policy
631   in effect for a set of users.  Section 10 describes the
632   administration of this object, and the relationship between it and
633   particular objects.
634
635         ( 1.3.6.1.4.1.42.2.27.8.2.1
636         NAME 'pwdPolicy'
637         SUP top
638         AUXILIARY
639         MUST ( pwdAttribute )
640         MAY ( pwdMinAge $ pwdMaxAge $ pwdInHistory $ pwdCheckQuality $
641         pwdMinLength $ pwdMaxLength $ pwdExpireWarning $
642         pwdGraceAuthNLimit $ pwdGraceExpiry $ pwdLockout $
643         pwdLockoutDuration $ pwdMaxFailure $ pwdFailureCountInterval $
644         pwdMustChange $ pwdAllowUserChange $ pwdSafeModify $
645         pwdMinDelay $ pwdMaxDelay $ pwdMaxIdle ) )
646
6475.2.  Attribute Types used in the pwdPolicy ObjectClass
648
649   Following are the attribute types used by the pwdPolicy object class.
650
6515.2.1.  pwdAttribute
652
653   This holds the name of the attribute to which the password policy is
654   applied.  For example, the password policy may be applied to the
655   userPassword attribute.
656
657         ( 1.3.6.1.4.1.42.2.27.8.1.1
658         NAME 'pwdAttribute'
659         EQUALITY objectIdentifierMatch
660         SYNTAX 1.3.6.1.4.1.1466.115.121.1.38 )
661
6625.2.2.  pwdMinAge
663
664   This attribute holds the number of seconds that must elapse between
665   modifications to the password.  If this attribute is not present, 0
666   seconds is assumed.
667
668
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676         ( 1.3.6.1.4.1.42.2.27.8.1.2
677         NAME 'pwdMinAge'
678         EQUALITY integerMatch
679         ORDERING integerOrderingMatch
680         SYNTAX 1.3.6.1.4.1.1466.115.121.1.27
681         SINGLE-VALUE )
682
6835.2.3.  pwdMaxAge
684
685   This attribute holds the number of seconds after which a modified
686   password will expire.
687
688   If this attribute is not present, or if the value is 0 the password
689   does not expire.  If not 0, the value must be greater than or equal
690   to the value of the pwdMinAge.
691
692         ( 1.3.6.1.4.1.42.2.27.8.1.3
693         NAME 'pwdMaxAge'
694         EQUALITY integerMatch
695         ORDERING integerOrderingMatch
696         SYNTAX 1.3.6.1.4.1.1466.115.121.1.27
697         SINGLE-VALUE )
698
6995.2.4.  pwdInHistory
700
701   This attribute specifies the maximum number of used passwords stored
702   in the pwdHistory attribute.
703
704   If this attribute is not present, or if the value is 0, used
705   passwords are not stored in the pwdHistory attribute and thus may be
706   reused.
707
708         ( 1.3.6.1.4.1.42.2.27.8.1.4
709         NAME 'pwdInHistory'
710         EQUALITY integerMatch
711         ORDERING integerOrderingMatch
712         SYNTAX 1.3.6.1.4.1.1466.115.121.1.27
713         SINGLE-VALUE )
714
7155.2.5.  pwdCheckQuality
716
717   {TODO: Consider changing the syntax to OID.  Each OID will list a
718   quality rule (like min len, # of special characters, etc).  These
719   rules can be specified outside this document.}
720
721   {TODO: Note that even though this is meant to be a check that happens
722   during password modification, it may also be allowed to happen during
723   authN.  This is useful for situations where the password is encrypted
724
725
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732   when modified, but decrypted when used to authN.}
733
734   This attribute indicates how the password quality will be verified
735   while being modified or added.  If this attribute is not present, or
736   if the value is '0', quality checking will not be enforced.  A value
737   of '1' indicates that the server will check the quality, and if the
738   server is unable to check it (due to a hashed password or other
739   reasons) it will be accepted.  A value of '2' indicates that the
740   server will check the quality, and if the server is unable to verify
741   it, it will return an error refusing the password.
742
743         ( 1.3.6.1.4.1.42.2.27.8.1.5
744         NAME 'pwdCheckQuality'
745         EQUALITY integerMatch
746         ORDERING integerOrderingMatch
747         SYNTAX 1.3.6.1.4.1.1466.115.121.1.27
748         SINGLE-VALUE )
749
7505.2.6.  pwdMinLength
751
752   When quality checking is enabled, this attribute holds the minimum
753   number of characters that must be used in a password.  If this
754   attribute is not present, no minimum password length will be
755   enforced.  If the server is unable to check the length (due to a
756   hashed password or otherwise), the server will, depending on the
757   value of the pwdCheckQuality attribute, either accept the password
758   without checking it ('0' or '1') or refuse it ('2').
759
760         ( 1.3.6.1.4.1.42.2.27.8.1.6
761         NAME 'pwdMinLength'
762         EQUALITY integerMatch
763         ORDERING integerOrderingMatch
764         SYNTAX 1.3.6.1.4.1.1466.115.121.1.27
765         SINGLE-VALUE )
766
7675.2.7.  pwdMaxLength
768
769   When quality checking is enabled, this attribute holds the maximum
770   number of characters that may be used in a password.  If this
771   attribute is not present, no maximum password length will be
772   enforced.  If the server is unable to check the length (due to a
773   hashed password or otherwise), the server will, depending on the
774   value of the pwdCheckQuality attribute, either accept the password
775   without checking it ('0' or '1') or refuse it ('2').
776
777
778
779
780
781
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787
788         ( 1.3.6.1.4.1.42.2.27.8.1.31
789         NAME 'pwdMaxLength'
790         EQUALITY integerMatch
791         ORDERING integerOrderingMatch
792         SYNTAX 1.3.6.1.4.1.1466.115.121.1.27
793         SINGLE-VALUE )
794
7955.2.8.  pwdExpireWarning
796
797   This attribute specifies the maximum number of seconds before a
798   password is due to expire that expiration warning messages will be
799   returned to an authenticating user.
800
801   If this attribute is not present, or if the value is 0 no warnings
802   will be returned.  If not 0, the value must be smaller than the value
803   of the pwdMaxAge attribute.
804
805         ( 1.3.6.1.4.1.42.2.27.8.1.7
806         NAME 'pwdExpireWarning'
807         EQUALITY integerMatch
808         ORDERING integerOrderingMatch
809         SYNTAX 1.3.6.1.4.1.1466.115.121.1.27
810         SINGLE-VALUE )
811
8125.2.9.  pwdGraceAuthNLimit
813
814   This attribute specifies the number of times an expired password can
815   be used to authenticate.  If this attribute is not present or if the
816   value is 0, authentication will fail.
817
818         ( 1.3.6.1.4.1.42.2.27.8.1.8
819         NAME 'pwdGraceAuthNLimit'
820         EQUALITY integerMatch
821         ORDERING integerOrderingMatch
822         SYNTAX 1.3.6.1.4.1.1466.115.121.1.27
823         SINGLE-VALUE )
824
8255.2.10.  pwdGraceExpiry
826
827   This attribute specifies the number of seconds the grace
828   authentications are valid.  If this attribute is not present or if
829   the value is 0, there is no time limit on the grace authentications.
830
831         ( 1.3.6.1.4.1.42.2.27.8.1.30
832         NAME 'pwdGraceExpiry'
833         EQUALITY integerMatch
834         ORDERING integerOrderingMatch
835         SYNTAX 1.3.6.1.4.1.1466.115.121.1.27
836
837
838
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843
844         SINGLE-VALUE )
845
8465.2.11.  pwdLockout
847
848   This attribute indicates, when its value is "TRUE", that the password
849   may not be used to authenticate after a specified number of
850   consecutive failed bind attempts.  The maximum number of consecutive
851   failed bind attempts is specified in pwdMaxFailure.
852
853   If this attribute is not present, or if the value is "FALSE", the
854   password may be used to authenticate when the number of failed bind
855   attempts has been reached.
856
857         ( 1.3.6.1.4.1.42.2.27.8.1.9
858         NAME 'pwdLockout'
859         EQUALITY booleanMatch
860         SYNTAX 1.3.6.1.4.1.1466.115.121.1.7
861         SINGLE-VALUE )
862
8635.2.12.  pwdLockoutDuration
864
865   This attribute holds the number of seconds that the password cannot
866   be used to authenticate due to too many failed bind attempts.  If
867   this attribute is not present, or if the value is 0 the password
868   cannot be used to authenticate until reset by a password
869   administrator.
870
871         ( 1.3.6.1.4.1.42.2.27.8.1.10
872         NAME 'pwdLockoutDuration'
873         EQUALITY integerMatch
874         ORDERING integerOrderingMatch
875         SYNTAX 1.3.6.1.4.1.1466.115.121.1.27
876         SINGLE-VALUE )
877
8785.2.13.  pwdMaxFailure
879
880   This attribute specifies the number of consecutive failed bind
881   attempts after which the password may not be used to authenticate.
882   If this attribute is not present, or if the value is 0, this policy
883   is not checked, and the value of pwdLockout will be ignored.
884
885         ( 1.3.6.1.4.1.42.2.27.8.1.11
886         NAME 'pwdMaxFailure'
887         EQUALITY integerMatch
888         SYNTAX 1.3.6.1.4.1.1466.115.121.1.27
889         ORDERING integerOrderingMatch
890         SINGLE-VALUE )
891
892
893
894
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899
9005.2.14.  pwdFailureCountInterval
901
902   This attribute holds the number of seconds after which the password
903   failures are purged from the failure counter, even though no
904   successful authentication occurred.
905
906   If this attribute is not present, or if its value is 0, the failure
907   counter is only reset by a successful authentication.
908
909         ( 1.3.6.1.4.1.42.2.27.8.1.12
910         NAME 'pwdFailureCountInterval'
911         EQUALITY integerMatch
912         SYNTAX 1.3.6.1.4.1.1466.115.121.1.27
913         ORDERING integerOrderingMatch
914         SINGLE-VALUE )
915
9165.2.15.  pwdMustChange
917
918   This attribute specifies with a value of "TRUE" that users must
919   change their passwords when they first bind to the directory after a
920   password is set or reset by a password administrator.  If this
921   attribute is not present, or if the value is "FALSE", users are not
922   required to change their password upon binding after the password
923   administrator sets or resets the password.  This attribute is not set
924   due to any actions specified by this document, it is typically set by
925   a password administrator after resetting a user's password.
926
927         ( 1.3.6.1.4.1.42.2.27.8.1.13
928         NAME 'pwdMustChange'
929         EQUALITY booleanMatch
930         SYNTAX 1.3.6.1.4.1.1466.115.121.1.7
931         SINGLE-VALUE )
932
9335.2.16.  pwdAllowUserChange
934
935   This attribute indicates whether users can change their own
936   passwords, although the change operation is still subject to access
937   control.  If this attribute is not present, a value of "TRUE" is
938   assumed.  This attribute is intended to be used in the absence of an
939   access control mechanism.
940
941         ( 1.3.6.1.4.1.42.2.27.8.1.14
942         NAME 'pwdAllowUserChange'
943         EQUALITY booleanMatch
944         SYNTAX 1.3.6.1.4.1.1466.115.121.1.7
945         SINGLE-VALUE )
946
947
948
949
950
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954
955
9565.2.17.  pwdSafeModify
957
958   This attribute specifies whether or not the existing password must be
959   sent along with the new password when being changed.  If this
960   attribute is not present, a "FALSE" value is assumed.
961
962         ( 1.3.6.1.4.1.42.2.27.8.1.15
963         NAME 'pwdSafeModify'
964         EQUALITY booleanMatch
965         SYNTAX 1.3.6.1.4.1.1466.115.121.1.7
966         SINGLE-VALUE )
967
9685.2.18.  pwdMinDelay
969
970   This attribute specifies the number of seconds to delay responding to
971   the first failed authentication attempt.  If this attribute is not
972   set or is 0, no delays will be used. pwdMaxDelay must also be
973   specified if pwdMinDelay is set.
974
975         ( 1.3.6.1.4.1.42.2.27.8.1.24
976         NAME 'pwdMinDelay'
977         EQUALITY integerMatch
978         ORDERING integerOrderingMatch
979         SYNTAX 1.3.6.1.4.1.1466.115.121.1.27
980         SINGLE-VALUE )
981
9825.2.19.  pwdMaxDelay
983
984   This attribute specifies the maximum number of seconds to delay when
985   responding to a failed authentication attempt.  The time specified in
986   pwdMinDelay is used as the starting time and is then doubled on each
987   failure until the delay time is greater than or equal to pwdMaxDelay
988   (or a successful authentication occurs, which resets the failure
989   counter). pwdMinDelay must be specified if pwdMaxDelay is set.
990
991         ( 1.3.6.1.4.1.42.2.27.8.1.25
992         NAME 'pwdMaxDelay'
993         EQUALITY integerMatch
994         ORDERING integerOrderingMatch
995         SYNTAX 1.3.6.1.4.1.1466.115.121.1.27
996         SINGLE-VALUE )
997
9985.2.20.  pwdMaxIdle
999
1000   This attribute specifies the number of seconds an account may remain
1001   unused before it becomes locked.  If this attribute is not set or is
1002   0, no check is performed.
1003
1004
1005
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1011
1012         ( 1.3.6.1.4.1.42.2.27.8.1.26
1013         NAME 'pwdMaxIdle'
1014         EQUALITY integerMatch
1015         ORDERING integerOrderingMatch
1016         SYNTAX 1.3.6.1.4.1.1466.115.121.1.27
1017         SINGLE-VALUE )
1018
10195.3.  Attribute Types for Password Policy State Information
1020
1021   Password policy state information must be maintained for each user.
1022   The information is located in each user entry as a set of operational
1023   attributes.  These operational attributes are: pwdChangedTime,
1024   pwdAccountLockedTime, pwdFailureTime, pwdHistory, pwdGraceUseTime,
1025   pwdReset, pwdPolicySubEntry, pwdStartTime, pwdEndTime,
1026   pwdLastSuccess.
1027
10285.3.1.  Password Policy State Attribute Option
1029
1030   Since the password policy could apply to several attributes used to
1031   store passwords, each of the above operational attributes must have
1032   an option to specify which pwdAttribute it applies to.  The password
1033   policy option is defined as the following:
1034
1035   pwd-<passwordAttribute>
1036
1037   where passwordAttribute is a string following the OID syntax
1038   (1.3.6.1.4.1.1466.115.121.1.38).  The attribute type descriptor
1039   (short name) MUST be used.
1040
1041   For example, if the pwdPolicy object has for pwdAttribute
1042   "userPassword" then the pwdChangedTime operational attribute, in a
1043   user entry, will be:
1044
1045   pwdChangedTime;pwd-userPassword: 20000103121520Z
1046
1047   This attribute option follows sub-typing semantics.  If a client
1048   requests a password policy state attribute to be returned in a search
1049   operation, and does not specify an option, all subtypes of that
1050   policy state attribute are returned.
1051
10525.3.2.  pwdChangedTime
1053
1054   This attribute specifies the last time the entry's password was
1055   changed.  This is used by the password expiration policy.  If this
1056   attribute does not exist, the password will never expire.
1057
1058
1059
1060
1061
1062
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1067
1068         ( 1.3.6.1.4.1.42.2.27.8.1.16
1069         NAME 'pwdChangedTime'
1070         DESC 'The time the password was last changed'
1071         EQUALITY generalizedTimeMatch
1072         ORDERING generalizedTimeOrderingMatch
1073         SYNTAX 1.3.6.1.4.1.1466.115.121.1.24
1074         SINGLE-VALUE
1075         NO-USER-MODIFICATION
1076         USAGE directoryOperation )
1077
10785.3.3.  pwdAccountLockedTime
1079
1080   This attribute holds the time that the user's account was locked.  A
1081   locked account means that the password may no longer be used to
1082   authenticate.  A 000001010000Z value means that the account has been
1083   locked permanently, and that only a password administrator can unlock
1084   the account.
1085
1086         ( 1.3.6.1.4.1.42.2.27.8.1.17
1087         NAME 'pwdAccountLockedTime'
1088         DESC 'The time an user account was locked'
1089         EQUALITY generalizedTimeMatch
1090         ORDERING generalizedTimeOrderingMatch
1091         SYNTAX 1.3.6.1.4.1.1466.115.121.1.24
1092         SINGLE-VALUE
1093         NO-USER-MODIFICATION
1094         USAGE directoryOperation )
1095
10965.3.4.  pwdFailureTime
1097
1098   This attribute holds the timestamps of the consecutive authentication
1099   failures.
1100
1101         ( 1.3.6.1.4.1.42.2.27.8.1.19
1102         NAME 'pwdFailureTime'
1103         DESC 'The timestamps of the last consecutive authentication
1104         failures'
1105         EQUALITY generalizedTimeMatch
1106         ORDERING generalizedTimeOrderingMatch
1107         SYNTAX 1.3.6.1.4.1.1466.115.121.1.24
1108         NO-USER-MODIFICATION
1109         USAGE directoryOperation )
1110
11115.3.5.  pwdHistory
1112
1113   This attribute holds a history of previously used passwords.  Values
1114   of this attribute are transmitted in string format as given by the
1115   following ABNF:
1116
1117
1118
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1123
1124      pwdHistory = time "#" syntaxOID "#" length "#" data
1125
1126      time       = GeneralizedTime
1127
1128      syntaxOID  = numericoid    ; the string representation of the
1129                                 ; dotted-decimal OID that defines the
1130                                 ; syntax used to store the password.
1131
1132      length     = number        ; the number of octets in data.
1133
1134      data       = <octets representing the password in the format
1135                    specified by syntaxOID>.
1136
1137   GeneralizedTime is specified in 3.3.13 of [RFC4517]. numericoid and
1138   number are specified in 1.4 of [RFC4512].
1139
1140   This format allows the server to store, and transmit a history of
1141   passwords that have been used.  In order for equality matching to
1142   function properly, the time field needs to adhere to a consistent
1143   format.  For this purpose, the time field MUST be in GMT format.
1144
1145         ( 1.3.6.1.4.1.42.2.27.8.1.20
1146         NAME 'pwdHistory'
1147         DESC 'The history of user s passwords'
1148         EQUALITY octetStringMatch
1149         SYNTAX 1.3.6.1.4.1.1466.115.121.1.40
1150         NO-USER-MODIFICATION
1151         USAGE directoryOperation )
1152
11535.3.6.  pwdGraceUseTime
1154
1155   This attribute holds the timestamps of grace authentications after a
1156   password has expired.
1157
1158         ( 1.3.6.1.4.1.42.2.27.8.1.21
1159         NAME 'pwdGraceUseTime'
1160         DESC 'The timestamps of the grace authentication after the
1161         password has expired'
1162         EQUALITY generalizedTimeMatch
1163         SYNTAX 1.3.6.1.4.1.1466.115.121.1.24
1164         NO-USER-MODIFICATION
1165         USAGE directoryOperation )
1166
11675.3.7.  pwdReset
1168
1169   This attribute holds a flag to indicate (when TRUE) that the password
1170   has been updated by the password administrator and must be changed by
1171   the user.
1172
1173
1174
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1179
1180         ( 1.3.6.1.4.1.42.2.27.8.1.22
1181         NAME 'pwdReset'
1182         DESC 'The indication that the password has been reset'
1183         EQUALITY booleanMatch
1184         SYNTAX 1.3.6.1.4.1.1466.115.121.1.7
1185         SINGLE-VALUE
1186         USAGE directoryOperation )
1187
11885.3.8.  pwdPolicySubentry
1189
1190   This attribute points to the pwdPolicy subentry in effect for this
1191   object.
1192
1193         ( 1.3.6.1.4.1.42.2.27.8.1.23
1194         NAME 'pwdPolicySubentry'
1195         DESC 'The pwdPolicy subentry in effect for this object'
1196         EQUALITY distinguishedNameMatch
1197         SYNTAX 1.3.6.1.4.1.1466.115.121.1.12
1198         SINGLE-VALUE
1199         NO-USER-MODIFICATION
1200         USAGE directoryOperation )
1201
12025.3.9.  pwdStartTime
1203
1204   This attribute specifies the time the entry's password becomes valid
1205   for authentication.  Authentication attempts made before this time
1206   will fail.  If this attribute does not exist, then no restriction
1207   applies.
1208
1209         ( 1.3.6.1.4.1.42.2.27.8.1.27
1210         NAME 'pwdStartTime'
1211         DESC 'The time the password becomes enabled'
1212         EQUALITY generalizedTimeMatch
1213         ORDERING generalizedTimeOrderingMatch
1214         SYNTAX 1.3.6.1.4.1.1466.115.121.1.24
1215         SINGLE-VALUE
1216         NO-USER-MODIFICATION
1217         USAGE directoryOperation )
1218
12195.3.10.  pwdEndTime
1220
1221   This attribute specifies the time the entry's password becomes
1222   invalid for authentication.  Authentication attempts made after this
1223   time will fail, regardless of expiration or grace settings.  If this
1224   attribute does not exist, then this restriction does not apply.
1225
1226
1227
1228
1229
1230
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1235
1236         ( 1.3.6.1.4.1.42.2.27.8.1.28
1237         NAME 'pwdEndTime'
1238         DESC 'The time the password becomes disabled'
1239         EQUALITY generalizedTimeMatch
1240         ORDERING generalizedTimeOrderingMatch
1241         SYNTAX 1.3.6.1.4.1.1466.115.121.1.24
1242         SINGLE-VALUE
1243         NO-USER-MODIFICATION
1244         USAGE directoryOperation )
1245
1246   Note that pwdStartTime may be set to a time greater than or equal to
1247   pwdEndTime; this simply disables the account.
1248
12495.3.11.  pwdLastSuccess
1250
1251   This attribute holds the timestamp of the last successful
1252   authentication.
1253
1254         ( 1.3.6.1.4.1.42.2.27.8.1.29
1255         NAME 'pwdLastSuccess'
1256         DESC 'The timestamp of the last successful authentication'
1257         EQUALITY generalizedTimeMatch
1258         ORDERING generalizedTimeOrderingMatch
1259         SYNTAX 1.3.6.1.4.1.1466.115.121.1.24
1260         SINGLE-VALUE
1261         NO-USER-MODIFICATION
1262         USAGE directoryOperation )
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
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1291
12926.  Controls used for Password Policy
1293
1294   This section details the controls used while enforcing password
1295   policy.  A request control is defined that is sent by a client with a
1296   request operation in order to elicit a response control.  The
1297   response control contains various warnings and errors associated with
1298   password policy.
1299
1300   {TODO: add a note about advertisement and discovery}
1301
13026.1.  Request Control
1303
1304   This control MAY be sent with any LDAP request message in order to
1305   convey to the server that this client is aware of, and can process
1306   the response control described in this document.  When a server
1307   receives this control, it will return the response control when
1308   appropriate and with the proper data.
1309
1310   The controlType is 1.3.6.1.4.1.42.2.27.8.5.1 and the criticality may
1311   be TRUE or FALSE.  There is no controlValue.
1312
13136.2.  Response Control
1314
1315   If the client has sent a passwordPolicyRequest control, the server
1316   (when solicited by the inclusion of the request control) sends this
1317   control with the following operation responses: bindResponse,
1318   modifyResponse, addResponse, compareResponse and possibly
1319   extendedResponse, to inform of various conditions, and MAY be sent
1320   with other operations (in the case of the changeAfterReset error).
1321   The controlType is 1.3.6.1.4.1.42.2.27.8.5.1 and the controlValue is
1322   the BER encoding of the following type:
1323
1324      PasswordPolicyResponseValue ::= SEQUENCE {
1325         warning [0] CHOICE {
1326            timeBeforeExpiration [0] INTEGER (0 .. maxInt),
1327            graceAuthNsRemaining [1] INTEGER (0 .. maxInt) } OPTIONAL,
1328         error   [1] ENUMERATED {
1329            passwordExpired             (0),
1330            accountLocked               (1),
1331            changeAfterReset            (2),
1332            passwordModNotAllowed       (3),
1333            mustSupplyOldPassword       (4),
1334            insufficientPasswordQuality (5),
1335            passwordTooShort            (6),
1336            passwordTooYoung            (7),
1337            passwordInHistory           (8) } OPTIONAL }
1338
1339   The timeBeforeExpiration warning specifies the number of seconds
1340
1341
1342
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1346
1347
1348   before a password will expire.  The graceAuthNsRemaining warning
1349   specifies the remaining number of times a user will be allowed to
1350   authenticate with an expired password.  The passwordExpired error
1351   signifies that the password has expired and must be reset.  The
1352   changeAfterReset error signifies that the password must be changed
1353   before the user will be allowed to perform any operation other than
1354   bind and modify.  The passwordModNotAllowed error is set when a user
1355   is restricted from changing her password.  The
1356   insufficientPasswordQuality error is set when a password doesn't pass
1357   quality checking.  The passwordTooYoung error is set if the age of
1358   the password to be modified is not yet old enough.
1359
1360   Typically, only either a warning or an error will be encoded though
1361   there may be exceptions.  For example, if the user is required to
1362   change a password after the password administrator set it, and the
1363   password will expire in a short amount of time, the control may
1364   include the timeBeforeExpiration warning and the changeAfterReset
1365   error.
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
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1402
1403
14047.  Policy Decision Points
1405
1406   Following are a number of procedures used to make policy decisions.
1407   These procedures are typically performed by the server while
1408   processing an operation.
1409
1410   The following sections contain detailed instructions that refer to
1411   attributes of the pwdPolicy object class.  When doing so, the
1412   attribute of the pwdPolicy object that governs the entry being
1413   discussed is implied.
1414
14157.1.  Locked Account Check
1416
1417   A status of true is returned to indicate that the account is locked
1418   if any of these conditions are met:
1419
1420   o  The value of the pwdAccountLockedTime attribute is 000001010000Z.
1421
1422   o  The current time is less than the value of the pwdStartTime
1423      attribute.
1424
1425   o  The current time is greater than or equal to the value of the
1426      pwdEndTime attribute.
1427
1428   o  The current time is greater than or equal to the value of the
1429      pwdLastSuccess attribute added to the value of the pwdMaxIdle
1430      attribute.
1431
1432   o  The current time is less than the value of the
1433      pwdAccountLockedTime attribute added to the value of the
1434      pwdLockoutDuration.
1435
1436   Otherwise a status of false is returned.
1437
14387.2.  Password Must be Changed Now Check
1439
1440   A status of true is returned to indicate that the password must be
1441   changed if all of these conditions are met:
1442
1443   o  The pwdMustChange attribute is set to TRUE.
1444
1445   o  The pwdReset attribute is set to TRUE.
1446
1447   Otherwise a status of false is returned.
1448
1449
1450
1451
1452
1453
1454
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1459
14607.3.  Password Expiration Check
1461
1462   A status of true is returned indicating that the password has expired
1463   if the current time minus the value of pwdChangedTime is greater than
1464   the value of the pwdMaxAge.
1465
1466   Otherwise, a status of false is returned.
1467
14687.4.  Remaining Grace AuthN Check
1469
1470   If the pwdGraceExpiry attribute is present, and the current time is
1471   greater than the password expiration time plus the pwdGraceExpiry
1472   value, zero is returned.
1473
1474   If the pwdGraceUseTime attribute is present, the number of values in
1475   that attribute subtracted from the value of pwdGraceAuthNLimit is
1476   returned.  Otherwise zero is returned.  A positive result specifies
1477   the number of remaining grace authentications.
1478
14797.5.  Time Before Expiration Check
1480
1481   If the pwdExpireWarning attribute is not present a zero status is
1482   returned.  Otherwise the following steps are followed:
1483
1484   Subtract the time stored in pwdChangedTime from the current time to
1485   arrive at the password's age.  If the password's age is greater than
1486   than the value of the pwdMaxAge attribute, a zero status is returned.
1487   Subtract the value of the pwdExpireWarning attribute from the value
1488   of the pwdMaxAge attribute to arrive at the warning age.  If the
1489   password's age is equal to or greater than the warning age, the value
1490   of pwdMaxAge minus the password's age is returned.
1491
14927.6.  Intruder Lockout Check
1493
1494   A status of true indicating that an intruder has been detected is
1495   returned if the following conditions are met:
1496
1497   o  The pwdLockout attribute is TRUE.
1498
1499   o  The number of values in the pwdFailureTime attribute that are
1500      younger than pwdFailureCountInterval is greater or equal to the
1501      pwdMaxFailure attribute.
1502
1503   Otherwise a status of false is returned.
1504
1505   While performing this check, values of pwdFailureTime that are old by
1506   more than pwdFailureCountInterval are purged and not counted.
1507
1508
1509
1510
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1515
15167.7.  Intruder Delay Check
1517
1518   If the pwdMinDelay attribute is 0 or not set, zero is returned.
1519
1520   Otherwise, a delay time is computed based on the number of values in
1521   the pwdFailureTime attribute.  If the computed value is greater than
1522   the pwdMaxDelay attribute, the pwdMaxDelay value is returned.
1523
1524   While performing this check, values of pwdFailureTime that are old by
1525   more than pwdFailureCountInterval are purged and not counted.
1526
15277.8.  Password Too Young Check
1528
1529   If the Section 7.2 check returned true then this check will return
1530   false, to allow the password to be changed.
1531
1532   A status of true indicating that not enough time has passed since the
1533   password was last updated is returned if:
1534
1535   o  The value of pwdMinAge is non-zero and pwdChangedTime is present.
1536
1537   o  The value of pwdMinAge is greater than the current time minus the
1538      value of pwdChangedTime.
1539
1540   Otherwise a false status is returned.
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
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1571
15728.  Server Policy Enforcement Points
1573
1574   The server SHOULD enforce that the password attribute subject to a
1575   password policy as defined in this document, contains one and only
1576   one password value.
1577
1578   Note: The case where a single password value is stored in multiple
1579   formats simultaneously is still considered to be only one password
1580   value.
1581
1582   The scenarios in the following operations assume that the client has
1583   attached a passwordPolicyRequest control to the request message of
1584   the operation.  In the event that the passwordPolicyRequest control
1585   was not sent, no passwordPolicyResponse control is returned.  All
1586   other instructions remain the same.
1587
1588   For successfully completed operations, unless otherwise stated, no
1589   passwordPolicyResponse control is returned.
1590
15918.1.  Password-based Authentication
1592
1593   This section contains the policy enforcement rules and policy data
1594   updates used while validating a password.  Operations that validate
1595   passwords include, but are not limited to, the Bind operation where
1596   the simple choice specifies a password, and the Compare operation
1597   where the attribute being compared holds a password.  Note that while
1598   the Compare operation does not authenticate a user to the LDAP
1599   server, it may be used by an external application for purposes of
1600   authentication.
1601
16028.1.1.  Fail if the account is locked
1603
1604   If the account is locked as specified in Section 7.1, the server
1605   fails the operation with an appropriate resultCode (i.e.
1606   invalidCredentials (49) in the case of a bind operation, compareFalse
1607   (5) in the case of a compare operation, etc.).  The server MAY set
1608   the error: accountLocked (1) in the passwordPolicyResponse in the
1609   controls field of the message.
1610
16118.1.2.  Validated Password Procedures
1612
1613   If the validation operation indicates that the password validated,
1614   these procedures are followed in order:
1615
16168.1.2.1.  Policy state updates
1617
1618   Delete the pwdFailureTime and pwdAccountLockedTime attributes.
1619
1620
1621
1622
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1627
1628   Set the value of the pwdLastSuccess attribute to the current time.
1629
1630   Note: setting pwdLastSuccess is optional, but it is required if the
1631   policy has pwdMaxIdle defined.
1632
16338.1.2.2.  Password must be changed now
1634
1635   If the decision in Section 7.2 returns true, the server sends to the
1636   client a response with an appropriate successful resultCode (i.e.
1637   success (0), compareTrue (6), etc.), and includes the
1638   passwordPolicyResponse in the controls field of the bindResponse
1639   message with the warning: changeAfterReset specified.
1640
1641   For bind, the server MUST then disallow all operations issued by this
1642   user except modify password, bind, unbind, abandon and StartTLS
1643   extended operation.
1644
16458.1.2.3.  Expired password
1646
1647   If the password has expired as per Section 7.3, the server either
1648   returns a success or failure based on the state of grace
1649   authentications.
1650
16518.1.2.3.1.  Remaining Grace Authentications
1652
1653   If there are remaining grace authentications as per Section 7.4, the
1654   server adds a new value with the current time in pwdGraceUseTime.
1655   Then it sends to the client a response with an appropriate successful
1656   resultCode (i.e. success (0), compareTrue (6), etc.), and includes
1657   the passwordPolicyResponse in the controls field of the response
1658   message with the warning: graceAuthNsRemaining choice set to the
1659   number of grace authentications left.
1660
1661   Implementor's note: The system time of the host machine may be more
1662   granular than is needed to ensure unique values of this attribute.
1663   It is recommended that a mechanism is used to ensure unique
1664   generalized time values.  The fractional seconds field may be used
1665   for this purpose.
1666
16678.1.2.3.2.  No Remaining Grace Authentications
1668
1669   If there are no remaining grace authentications, the server fails the
1670   operation with an appropriate resultCode (invalidCredentials (49),
1671   compareFalse (5), etc.), and includes the passwordPolicyResponse in
1672   the controls field of the bindResponse message with the error:
1673   passwordExpired (0) set.
1674
1675
1676
1677
1678
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1683
16848.1.2.4.  Expiration Warning
1685
1686   If the result of Section 7.5 is a positive number, the server sends
1687   to the client a response with an appropriate successful resultCode
1688   (i.e. success (0), compareTrue (6), etc.), and includes the
1689   passwordPolicyResponse in the controls field of the bindResponse
1690   message with the warning: timeBeforeExiration set to the value as
1691   described above.  Otherwise, the server sends a successful response,
1692   and omits the passwordPolicyResponse.
1693
16948.1.3.  AuthN Failed Procedures
1695
1696   If the authentication process indicates that the password failed
1697   validation due to invalid credentials, these procedures are followed:
1698
16998.1.3.1.  Policy state update
1700
1701   Add the current time as a value of the pwdFailureTime attribute.
1702
1703   Implementor's note: The system time of the host machine may be more
1704   granular than is needed to ensure unique values of this attribute.
1705   It is recommended that a mechanism is used to ensure unique
1706   generalized time values.  The fractional seconds field may be used
1707   for this purpose.
1708
17098.1.3.2.  Handle Intruder Detection
1710
1711   If the check in Section 7.6 returns a true state, the server locks
1712   the account by setting the value of the pwdAccountLockedTime
1713   attribute to the current time.  After locking the account, the server
1714   fails the operation with an appropriate resultCode
1715   (invalidCredentials (49), compareFalse (5), etc.), and includes the
1716   passwordPolicyResponse in the controls field of the message with the
1717   error: accountLocked (1).
1718
1719   If the check in Section 7.7 returns a non-zero value, the server
1720   waits that number of seconds before sending the authentication
1721   response back to the client.
1722
17238.2.  Password Update Operations
1724
1725   Because the password is stored in an attribute, various operations
1726   (like add and modify) may be used to create or update a password.
1727   But some alternate mechanisms have been defined or may be defined,
1728   such as the LDAP Password Modify Extended Operation [RFC3062].
1729
1730   While processing a password update, the server performs the following
1731   steps:
1732
1733
1734
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1739
17408.2.1.  Safe Modification
1741
1742   If pwdSafeModify is set to TRUE and if there is an existing password
1743   value, the server ensures that the password update operation includes
1744   the user's existing password.
1745
1746   When the LDAP modify operation is used to modify a password, this is
1747   done by specifying both a delete action and an add or replace action,
1748   where the delete action specifies the existing password, and the add
1749   or replace action specifies the new password.  Other password update
1750   operations SHOULD employ a similar mechanism.  Otherwise this policy
1751   will fail.
1752
1753   If the existing password is not specified, the server does not
1754   process the operation and sends the appropriate response message to
1755   the client with the resultCode: insufficientAccessRights (50), and
1756   includes the passwordPolicyResponse in the controls field of the
1757   response message with the error: mustSupplyOldPassword (4).
1758
17598.2.2.  Change After Reset
1760
1761   If the decision in Section 7.2 returns true, the server ensures that
1762   the password update operation contains no modifications other than
1763   the modification of the password attribute.  If other modifications
1764   exist, the server sends a response message to the client with the
1765   resultCode: insufficientAccessRights (50), and includes the
1766   passwordPolicyResponse in the controls field of the response message
1767   with the error: changeAfterReset (2).
1768
17698.2.3.  Rights Check
1770
1771   Check to see whether the bound identity has sufficient rights to
1772   update the password.  If the bound identity is a user changing its
1773   own password, this MAY be done by checking the pwdAllowUserChange
1774   attribute or using an access control mechanism.  The determination of
1775   this is implementation specific.  If the user is not allowed to
1776   update her password, the server sends a response message to the
1777   client with the resultCode: insufficientAccessRights (50), and
1778   includes the passwordPolicyResponse in the controls field of the
1779   response message with the error: passwordModNotAllowed (3).
1780
17818.2.4.  Too Early to Update
1782
1783   If the check in Section 7.8 results in a true status The server sends
1784   a response message to the client with the resultCode:
1785   constraintViolation (19), and includes the passwordPolicyResponse in
1786   the controls field of the response message with the error:
1787   passwordTooYoung (7).
1788
1789
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1795
17968.2.5.  Password Quality
1797
1798   Check the value of the pwdCheckQuality attribute.  If the value is
1799   non-zero, the server:
1800
1801   o  Ensure that the password meets the quality criteria enforced by
1802      the server.  This enforcement is implementation specific.  If the
1803      server is unable to check the quality (due to a hashed password or
1804      otherwise), the value of pwdCheckQuality is evaluated.  If the
1805      value is 1, operation continues.  If the value is 2, the server
1806      sends a response message to the client with the resultCode:
1807      constraintViolation (19), and includes the passwordPolicyResponse
1808      in the controls field of the response message with the error:
1809      insufficientPasswordQuality (5).
1810
1811      If the server is able to check the password quality, and the check
1812      fails, the server sends a response message to the client with the
1813      resultCode: constraintViolation (19), and includes the
1814      passwordPolicyResponse in the controls field of the response
1815      message with the error: insufficientPasswordQuality (5).
1816
1817   o  checks the value of the pwdMinLength attribute.  If the value is
1818      non-zero, it ensures that the new password is of at least the
1819      minimum length.
1820
1821      If the server is unable to check the length (due to a hashed
1822      password or otherwise), the value of pwdCheckQuality is evaluated.
1823      If the value is 1, operation continues.  If the value is 2, the
1824      server sends a response message to the client with the resultCode:
1825      constraintViolation (19), and includes the passwordPolicyResponse
1826      in the controls field of the response message with the error:
1827      passwordTooShort (6).
1828
1829      If the server is able to check the password length, and the check
1830      fails, the server sends a response message to the client with the
1831      resultCode: constraintViolation (19), and includes the
1832      passwordPolicyResponse in the controls field of the response
1833      message with the error: passwordTooShort (6).
1834
18358.2.6.  Invalid Reuse
1836
1837   If pwdInHistory is present and its value is non-zero, the server
1838   checks whether this password exists in the entry's pwdHistory
1839   attribute or in the current password attribute.  If the password does
1840   exist in the pwdHistory attribute or in the current password
1841   attribute, the server sends a response message to the client with the
1842   resultCode: constraintViolation (19), and includes the
1843   passwordPolicyResponse in the controls field of the response message
1844
1845
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1851
1852   with the error: passwordInHistory (8).
1853
18548.2.7.  Policy State Updates
1855
1856   If the steps have completed without causing an error condition, the
1857   server performs the following steps in order to update the necessary
1858   password policy state attributes:
1859
1860   If the value of either pwdMaxAge or pwdMinAge is non-zero, the server
1861   updates the pwdChangedTime attribute on the entry to the current
1862   time.
1863
1864   If the value of pwdInHistory is non-zero, the server adds the
1865   previous password (if one existed) to the pwdHistory attribute.  If
1866   the number of attributes held in the pwdHistory attribute exceeds the
1867   value of pwdInHistory, the server removes the oldest excess
1868   passwords.
1869
1870   If the value the pwdMustChange is TRUE and the modification is
1871   performed by a password administrator, then the pwdReset attribute is
1872   set to TRUE.  Otherwise, the pwdReset is removed from the user's
1873   entry if it exists.
1874
1875   The pwdFailureTime and pwdGraceUseTime attributes is removed from the
1876   user's entry if they exist.
1877
18788.3.  Other Operations
1879
1880   For operations other than bind, password update, unbind, abandon or
1881   StartTLS, if the decision in Section 7.2 returns true, the server
1882   sends a response message to the client with the resultCode:
1883   insufficientAccessRights (50), and includes the
1884   passwordPolicyResponse in the controls field of the response message
1885   with the error: changeAfterReset (2).
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
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1907
19089.  Client Policy Enforcement Points
1909
1910   These sections illustrate possible scenarios for each LDAP operation
1911   and define the types of responses that identify those scenarios.
1912
1913   The scenarios in the following operations assume that the client
1914   attached a passwordPolicyRequest control to the request message of
1915   the operation, and thus may receive a passwordPolicyResponse control
1916   in the response message.  In the event that the passwordPolicyRequest
1917   control was not sent, no passwordPolicyResponse control is returned.
1918   All other instructions remain the same.
1919
19209.1.  Bind Operation
1921
1922   For every bind response received, the client checks the resultCode of
1923   the bindResponse and checks for a passwordPolicyResponse control to
1924   determine if any of the following conditions are true and MAY prompt
1925   the user accordingly.
1926
1927   o  bindResponse.resultCode = insufficientAccessRights (50),
1928      passwordPolicyResponse.error = accountLocked (1): The password
1929      failure limit has been reached and the account is locked.  The
1930      user needs to retry later or contact the password administrator to
1931      reset the password.
1932
1933   o  bindResponse.resultCode = success (0),
1934      passwordPolicyResponse.error = changeAfterReset (2): The user is
1935      binding for the first time after the password administrator set
1936      the password.  In this scenario, the client SHOULD prompt the user
1937      to change his password immediately.
1938
1939   o  bindResponse.resultCode = success (0),
1940      passwordPolicyResponse.warning = graceAuthNsRemaining: The
1941      password has expired but there are remaining grace
1942      authentications.  The user needs to change it.
1943
1944   o  bindResponse.resultCode = invalidCredentials (49),
1945      passwordPolicyResponse.error = passwordExpired (0): The password
1946      has expired and there are no more grace authentications.  The user
1947      contacts the password administrator in order to have its password
1948      reset.
1949
1950   o  bindResponse.resultCode = success (0),
1951      passwordPolicyResponse.warning = timeBeforeExpiration: The user's
1952      password will expire in n number of seconds.
1953
1954
1955
1956
1957
1958
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1963
19649.2.  Modify Operations
1965
19669.2.1.  Modify Request
1967
1968   If the application or client encrypts the password prior to sending
1969   it in a password modification operation (whether done through
1970   modifyRequest or another password modification mechanism), it SHOULD
1971   check the values of the pwdMinLength, and pwdCheckQuality attributes
1972   and SHOULD enforce these policies.
1973
19749.2.2.  Modify Response
1975
1976   If the modifyRequest operation was used to change the password, or if
1977   another mechanism is used --such as an extendedRequest-- the
1978   modifyResponse or other appropriate response MAY contain information
1979   pertinent to password policy.  The client checks the resultCode of
1980   the response and checks for a passwordPolicyResponse control to
1981   determine if any of the following conditions are true and optionally
1982   notify the user of the condition.
1983
1984   o  pwdModResponse.resultCode = insufficientAccessRights (50),
1985      passwordPolicyResponse.error = mustSupplyOldPassword (4): The user
1986      attempted to change her password without specifying the old
1987      password but the password policy requires this.
1988
1989   o  pwdModResponse.resultCode = insufficientAccessRights (50),
1990      passwordPolicyResponse.error = changeAfterReset (2): The user must
1991      change her password before submitting any other LDAP requests.
1992
1993   o  pwdModResponse.resultCode = insufficientAccessRights (50),
1994      passwordPolicyResponse.error = passwordModNotAllowed (3): The user
1995      doesn't have sufficient rights to change his password.
1996
1997   o  pwdModResponse.resultCode = constraintViolation (19),
1998      passwordPolicyResponse.error = passwordTooYoung (7): It is too
1999      soon after the last password modification to change the password.
2000
2001   o  pwdModResponse.resultCode = constraintViolation (19),
2002      passwordPolicyResponse.error = insufficientPasswordQuality (5):
2003      The password failed quality checking.
2004
2005   o  pwdModResponse.resultCode = constraintViolation (19),
2006      passwordPolicyResponse.error = passwordTooShort (6): The length of
2007      the password is too short.
2008
2009   o  pwdModResponse.resultCode = constraintViolation (19),
2010      passwordPolicyResponse.error = passwordInHistory (8): The password
2011      has already been used; the user must choose a different one.
2012
2013
2014
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2018
2019
20209.3.  Add Operation
2021
2022   If a password is specified in an addRequest, the client checks the
2023   resultCode of the addResponse and checks for a passwordPolicyResponse
2024   control to determine if any of the following conditions are true and
2025   may prompt the user accordingly.
2026
2027   o  addResponse.resultCode = insufficientAccessRights (50),
2028      passwordPolicyResponse.error = passwordModNotAllowed (3): The user
2029      doesn't have sufficient rights to add this password.
2030
2031   o  addResponse.resultCode = constraintViolation (19),
2032      passwordPolicyResponse.error = insufficientPasswordQuality (5):
2033      The password failed quality checking.
2034
2035   o  addResponse.resultCode = constraintViolation (19),
2036      passwordPolicyResponse.error = passwordTooShort (6): The length of
2037      the password is too short.
2038
20399.4.  Compare Operation
2040
2041   When a compare operation is used to compare a password, the client
2042   checks the resultCode of the compareResponse and checks for a
2043   passwordPolicyResponse to determine if any of the following
2044   conditions are true and MAY prompt the user accordingly.  These
2045   conditions assume that the result of the comparison was true.
2046
2047   o  compareResponse.resultCode = compareFalse (5),
2048      passwordPolicyResponse.error = accountLocked (1): The password
2049      failure limit has been reached and the account is locked.  The
2050      user needs to retry later or contact the password administrator to
2051      reset the password.
2052
2053   o  compareResponse.resultCode = compareTrue (6),
2054      passwordPolicyResponse.warning = graceAuthNsRemaining: The
2055      password has expired but there are remaining grace
2056      authentications.  The user needs to change it.
2057
2058   o  compareResponse.resultCode = compareFalse (5),
2059      passwordPolicyResponse.error = passwordExpired (0): The password
2060      has expired and there are no more grace authentications.  The user
2061      must contact the password administrator to reset the password.
2062
2063   o  compareResponse.resultCode = compareTrue (6),
2064      passwordPolicyResponse.warning = timeBeforeExpiration: The user's
2065      password will expire in n number of seconds.
2066
2067
2068
2069
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2075
20769.5.  Other Operations
2077
2078   For operations other than bind, unbind, abandon or StartTLS, the
2079   client checks the result code and control to determine if the user
2080   needs to change the password immediately.
2081
2082   o  <Response>.resultCode = insufficientAccessRights (50),
2083      passwordPolicyResponse.error = changeAfterReset (2) : The user
2084      needs to change the password immediately.
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
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2131
213210.  Administration of the Password Policy
2133
2134   {TODO: Need to define an administrativeRole (need OID).  Need to
2135   describe whether pwdPolicy admin areas can overlap}
2136
2137   A password policy is defined for a particular subtree of the DIT by
2138   adding to an LDAP subentry whose immediate superior is the root of
2139   the subtree, the pwdPolicy auxiliary object class.  The scope of the
2140   password policy is defined by the SubtreeSpecification attribute of
2141   the LDAP subentry as specified in [RFC3672].
2142
2143   It is possible to define password policies for different password
2144   attributes within the same pwdPolicy entry, by specifying multiple
2145   values of the pwdAttribute.  But password policies could also be in
2146   separate sub entries as long as they are contained under the same
2147   LDAP subentry.
2148
2149   Only one policy may be in effect for a given password attribute in
2150   any entry.  If multiple policies exist which overlap in the range of
2151   entries affected, the resulting behavior is undefined.
2152
2153   Modifying the password policy MUST NOT result in any change in users'
2154   entries to which the policy applies.
2155
2156   It SHOULD be possible to overwrite the password policy for one user
2157   by defining a new policy in a subentry of the user entry.
2158
2159   Each object that is controlled by password policy advertises the
2160   subentry that is being used to control its policy in its
2161   pwdPolicySubentry attribute.  Clients wishing to examine or manage
2162   password policy for an object may interrogate the pwdPolicySubentry
2163   for that object in order to arrive at the proper pwdPolicy subentry.
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
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2186
2187
218811.  Password Policy and Replication
2189
2190   {TODO: This section needs to be changed to highlight the pitfalls of
2191   replication, suggest some implementation choices to overcome those
2192   pitfalls, but remove prescriptive language relating to the update of
2193   state information}
2194
2195   The pwdPolicy object defines the password policy for a portion of the
2196   DIT and MUST be replicated on all the replicas of this subtree, as
2197   any subentry would be, in order to have a consistent policy among all
2198   replicated servers.
2199
2200   The elements of the password policy that are related to the users are
2201   stored in the entry themselves as operational attributes.  As these
2202   attributes are subject to modifications even on a read-only replica,
2203   replicating them must be carefully considered.
2204
2205   The pwdChangedTime attribute MUST be replicated on all replicas, to
2206   allow expiration of the password.
2207
2208   The pwdReset attribute MUST be replicated on all replicas, to deny
2209   access to operations other than bind and modify password.
2210
2211   The pwdHistory attribute MUST be replicated to writable replicas.  It
2212   doesn't have to be replicated to a read-only replica, since the
2213   password will never be directly modified on this server.
2214
2215   The pwdAccountLockedTime, pwdFailureTime and pwdGraceUseTime
2216   attributes SHOULD be replicated to writable replicas, making the
2217   password policy global for all servers.  When the user entry is
2218   replicated to a read-only replica, these attributes SHOULD NOT be
2219   replicated.  This means that the number of failures, of grace
2220   authentications and the locking will take place on each replicated
2221   server.  For example, the effective number of failed attempts on a
2222   user password will be N x M (where N is the number of servers and M
2223   the value of pwdMaxFailure attribute).  Replicating these attributes
2224   to a read-only replica MAY reduce the number of tries globally but
2225   MAY also introduce some inconstancies in the way the password policy
2226   is applied.
2227
2228   Note: there are some situations where global replication of these
2229   state attributes may not be desired.  For example, if two clusters of
2230   replicas are geographically remote and joined by a slow network link,
2231   and their users only login from one of the two locations, it may be
2232   unnecessary to propagate all of the state changes from one cluster to
2233   the other.  Servers SHOULD allow administrators to control which
2234   attributes are replicated on a case-by-case basis.
2235
2236
2237
2238
2239Sermersheim, et al.     Expires January 19, 2015               [Page 40]
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2241Internet-Draft    Password Policy for LDAP Directories         July 2014
2242
2243
2244   Servers participating in a loosely consistent multi-master
2245   replication agreement SHOULD employ a mechanism which ensures
2246   uniqueness of values when populating the attributes pwdFailureTime
2247   and pwdGraceUseTime.  The method of achieving this is a local matter
2248   and may consist of using a single authoritative source for the
2249   generation of unique time values, or may consist of the use of the
2250   fractional seconds part to hold a replica identifier.
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295Sermersheim, et al.     Expires January 19, 2015               [Page 41]
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2298
2299
230012.  Security Considerations
2301
2302   This document defines a set of rules to implement in an LDAP server,
2303   in order to mitigate some of the security risks associated with the
2304   use of passwords and to make it difficult for password cracking
2305   programs to break into directories.
2306
2307   Authentication with a password MUST follow the recommendations made
2308   in [RFC4513].
2309
2310   Modifications of passwords SHOULD only occur when the connection is
2311   protected with confidentiality and secure authentication.
2312
2313   Access controls SHOULD be used to restrict access to the password
2314   policy attributes.  The attributes defined to maintain the password
2315   policy state information SHOULD only be modifiable by the password
2316   administrator or higher authority.  The pwdHistory attribute MUST be
2317   subject to the same level of access control as the attrbute holding
2318   the password.
2319
2320   As it is possible to define a password policy for one specific user
2321   by adding a subentry immediately under the user's entry, Access
2322   Controls SHOULD be used to restrict the use of the pwdPolicy object
2323   class or the LDAP subentry object class.
2324
2325   When the intruder detection password policy is enforced, the LDAP
2326   directory is subject to a denial of service attack.  A malicious user
2327   could deliberately lock out one specific user's account (or all of
2328   them) by sending bind requests with wrong passwords.  There is no way
2329   to protect against this kind of attack.  The LDAP directory server
2330   SHOULD log as much information as it can (such as client IP address)
2331   whenever an account is locked, in order to be able to identify the
2332   origin of the attack.  Denying anonymous access to the LDAP directory
2333   is also a way to restrict this kind of attack.  Using the login delay
2334   instead of the lockout mechanism will also help avoid this denial of
2335   service.
2336
2337   Returning certain status codes (such as passwordPolicyResponse.error
2338   = accountLocked) allows a denial of service attacker to know that it
2339   has successfully denied service to an account.  Servers SHOULD
2340   implement additional checks which return the same status when it is
2341   sensed that some number of failed authentication requests has occured
2342   on a single connection, or from a client address.  Server
2343   implementors are encouraged to invent other checks similar to this in
2344   order to thwart this type of DoS attack.
2345
2346
2347
2348
2349
2350
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2354
2355
235613.  IANA Considerations
2357
2358   In accordance with [RFC4520] the following registrations are
2359   requested.
2360
236113.1.  Object Identifiers
2362
2363   The OIDs used in this specification are derived from iso(1)
2364   identified-organization(3) dod(6) internet(1) private(4)
2365   enterprise(1) Sun(42) products(2) LDAP(27) ppolicy(8).  These OIDs
2366   have been in use since at least July 2001 when version 04 of this
2367   draft was published.  No additional OID assignment is being
2368   requested.
2369
237013.2.  LDAP Protocol Mechanisms
2371
2372   Registration of the protocol mechanisms specified in this document is
2373   requested.
2374
2375      Subject: Request for LDAP Protocol Mechanism Registration
2376
2377      Object Identifier: 1.3.6.1.4.1.42.2.27.8.5.1
2378
2379      Description: Password Policy Request and Response Control
2380
2381      Person & email address to contact for further information:
2382
2383         Howard Chu <hyc@symas.com>
2384
2385      Usage: Control
2386
2387      Specification: (I-D) draft-behera-ldap-password-policy
2388
2389      Author/Change Controller: IESG
2390
2391      Comments:
2392
239313.3.  LDAP Descriptors
2394
2395   Registration of the descriptors specified in this document is
2396   requested.
2397
2398      Subject: Request for LDAP Descriptor Registration
2399
2400      Descriptor (short name): see table
2401
2402      Object Identifier: see table
2403
2404
2405
2406
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2410
2411
2412      Description: see table
2413
2414      Person & email address to contact for further information:
2415
2416         Howard Chu <hyc@symas.com>
2417
2418      Specification: (I-D) draft-behera-ldap-password-policy
2419
2420      Author/Change Controller: IESG
2421
2422      Comments:
2423
2424      Name                    Type  OID
2425      ----------------------- ----  ------------------------------
2426      pwdPolicy               O     1.3.6.1.4.1.42.2.27.8.2.1
2427      pwdAttribute            A     1.3.6.1.4.1.42.2.27.8.1.1
2428      pwdMinAge               A     1.3.6.1.4.1.42.2.27.8.1.2
2429      pwdMaxAge               A     1.3.6.1.4.1.42.2.27.8.1.3
2430      pwdInHistory            A     1.3.6.1.4.1.42.2.27.8.1.4
2431      pwdCheckQuality         A     1.3.6.1.4.1.42.2.27.8.1.5
2432      pwdMinLength            A     1.3.6.1.4.1.42.2.27.8.1.6
2433      pwdMaxLength            A     1.3.6.1.4.1.42.2.27.8.1.31
2434      pwdExpireWarning        A     1.3.6.1.4.1.42.2.27.8.1.7
2435      pwdGraceAuthNLimit      A     1.3.6.1.4.1.42.2.27.8.1.8
2436      pwdGraceExpiry          A     1.3.6.1.4.1.42.2.27.8.1.30
2437      pwdLockout              A     1.3.6.1.4.1.42.2.27.8.1.9
2438      pwdLockoutDuration      A     1.3.6.1.4.1.42.2.27.8.1.10
2439      pwdMaxFailure           A     1.3.6.1.4.1.42.2.27.8.1.11
2440      pwdFailureCountInterval A     1.3.6.1.4.1.42.2.27.8.1.12
2441      pwdMustChange           A     1.3.6.1.4.1.42.2.27.8.1.13
2442      pwdAllowUserChange      A     1.3.6.1.4.1.42.2.27.8.1.14
2443      pwdSafeModify           A     1.3.6.1.4.1.42.2.27.8.1.15
2444      pwdMinDelay             A     1.3.6.1.4.1.42.2.27.8.1.24
2445      pwdMaxDelay             A     1.3.6.1.4.1.42.2.27.8.1.25
2446      pwdMaxIdle              A     1.3.6.1.4.1.42.2.27.8.1.26
2447      pwdChangedTime          A     1.3.6.1.4.1.42.2.27.8.1.16
2448      pwdAccountLockedTime    A     1.3.6.1.4.1.42.2.27.8.1.17
2449      pwdFailureTime          A     1.3.6.1.4.1.42.2.27.8.1.19
2450      pwdHistory              A     1.3.6.1.4.1.42.2.27.8.1.20
2451      pwdGraceUseTime         A     1.3.6.1.4.1.42.2.27.8.1.21
2452      pwdReset                A     1.3.6.1.4.1.42.2.27.8.1.22
2453      pwdPolicySubEntry       A     1.3.6.1.4.1.42.2.27.8.1.23
2454      pwdStartTime            A     1.3.6.1.4.1.42.2.27.8.1.27
2455      pwdEndTime              A     1.3.6.1.4.1.42.2.27.8.1.28
2456      pwdLastSuccess          A     1.3.6.1.4.1.42.2.27.8.1.29
2457
2458
2459
2460
2461
2462
2463Sermersheim, et al.     Expires January 19, 2015               [Page 44]
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2465Internet-Draft    Password Policy for LDAP Directories         July 2014
2466
2467
2468      Legend
2469      --------------------
2470      A => Attribute Type
2471      O => Object Class
2472
247313.4.  LDAP AttributeDescription Options
2474
2475   Registration of the AttributeDescription option specified in this
2476   document is requested.
2477
2478      Subject: Request for LDAP Attribute Description Option
2479      Registration
2480
2481      Option Name: pwd-
2482
2483      Family of Options: YES
2484
2485      Person & email address to contact for further information:
2486
2487         Howard Chu <hyc@symas.com>
2488
2489      Specification: (I-D) draft-behera-ldap-password-policy
2490
2491      Author/Change Controller: IESG
2492
2493      Comments:
2494
2495         Used with policy state attributes to specify to which password
2496         attribute the state belongs.
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
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2522
2523
252414.  Acknowledgement
2525
2526   This document is based in part on prior work done by Valerie Chu from
2527   Netscape Communications Corp, published as
2528   draft-vchu-ldap-pwd-policy-00.txt (December 1998).  Prasanta Behera
2529   participated in early revisions of this document.
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
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2578
2579
258015.  Normative References
2581
2582   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
2583              Requirement Levels", BCP 14, RFC 2119, March 1997.
2584
2585   [RFC2195]  Klensin, J., Catoe, R., and P. Krumviede, "IMAP/POP
2586              AUTHorize Extension for Simple Challenge/Response",
2587              RFC 2195, September 1997.
2588
2589   [RFC2831]  Leach, P. and C. Newman, "Using Digest Authentication as a
2590              SASL Mechanism", RFC 2831, May 2000.
2591
2592   [RFC3062]  Zeilenga, K., "LDAP Password Modify Extended Operation",
2593              RFC 3062, February 2001.
2594
2595   [RFC3672]  Zeilenga, K., "Subentries in the Lightweight Directory
2596              Access Protocol (LDAP)", RFC 3672, December 2003.
2597
2598   [RFC4422]  Melnikov, A. and K. Zeilenga, "Simple Authentication and
2599              Security Layer (SASL)", RFC 4422, June 2006.
2600
2601   [RFC4511]  Sermersheim, J., "Lightweight Directory Access Protocol
2602              (LDAP): The Protocol", RFC 4511, June 2006.
2603
2604   [RFC4512]  Zeilenga, K., "Lightweight Directory Access Protocol
2605              (LDAP): Directory Information Models", RFC 4512,
2606              June 2006.
2607
2608   [RFC4513]  Harrison, R., "Lightweight Directory Access Protocol
2609              (LDAP): Authentication Methods and Security Mechanisms",
2610              RFC 4513, June 2006.
2611
2612   [RFC4517]  Legg, S., "Lightweight Directory Access Protocol (LDAP):
2613              Syntaxes and Matching Rules", RFC 4517, June 2006.
2614
2615   [RFC4520]  Zeilenga, K., "Internet Assigned Numbers Authority (IANA)
2616              Considerations for the Lightweight Directory Access
2617              Protocol (LDAP)", BCP 64, RFC 4520, June 2006.
2618
2619   [X.680]    International Telecommunications Union, "Abstract Syntax
2620              Notation One (ASN.1): Specification of basic notation",
2621              ITU-T Recommendation X.680, July 2002.
2622
2623   [X.690]    International Telecommunications Union, "Information
2624              Technology - ASN.1 encoding rules: Specification of Basic
2625              Encoding Rules (BER),  Canonical Encoding Rules (CER) and
2626              Distinguished Encoding Rules (DER)", ITU-T
2627              Recommendation X.690, July 2002.
2628
2629
2630
2631Sermersheim, et al.     Expires January 19, 2015               [Page 47]
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2634
2635
2636Authors' Addresses
2637
2638   Jim Sermersheim
2639   Novell, Inc
2640   1800 South Novell Place
2641   Provo, Utah  84606
2642   US
2643
2644   Phone: +1 801 861-3088
2645   Email: jimse@novell.com
2646
2647
2648   Ludovic Poitou
2649   Sun Microsystems
2650   180, Avenue de l'Europe
2651   Zirst de Montbonnot, Saint Ismier cedex  38334
2652   FR
2653
2654   Phone: +33 476 188 212
2655   Email: ludovic.poitou@sun.com
2656
2657
2658   Howard Chu (editor)
2659   Symas Corp.
2660   18740 Oxnard Street, Suite 313A
2661   Tarzana, California  91356
2662   US
2663
2664   Phone: +1 818 757-7087
2665   Email: hyc@symas.com
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687Sermersheim, et al.     Expires January 19, 2015               [Page 48]
2688
2689