slapo-ppolicy

SLAPO_PPOLICY(5)              File Formats Manual             SLAPO_PPOLICY(5)



NAME
       slapo-ppolicy - Password Policy overlay to slapd

SYNOPSIS
       /etc/openldap/slapd.conf

DESCRIPTION
       The ppolicy overlay is an implementation of the most recent IETF
       Password Policy proposal for LDAP.   When instantiated, it intercepts,
       decodes and applies specific password policy controls to overall use of
       a backend database, changes to user password fields, etc.

       The overlay provides a variety of password control mechanisms.  They
       include password aging -- both minimum and maximum ages, password reuse
       and duplication control, account time-outs, mandatory password resets,
       acceptable password content, and even grace logins.  Different groups
       of users may be associated with different password policies, and there
       is no limit to the number of password policies that may be created.

       Note that some of the policies do not take effect when the operation is
       performed with the rootdn identity; all the operations, when performed
       with any other identity, may be subjected to constraints, like access
       control.

       Note that the IETF Password Policy proposal for LDAP makes sense when
       considering a single-valued password attribute, while the userPassword
       attribute allows multiple values.  This implementation enforces a
       single value for the userPassword attribute, despite its specification.


CONFIGURATION
       These slapd.conf configuration options apply to the ppolicy overlay.
       They should appear after the overlay directive.

       ppolicy_default <policyDN>
              Specify the DN of the pwdPolicy object to use when no specific
              policy is set on a given user's entry. If there is no specific
              policy for an entry and no default is given, then no policies
              will be enforced.

       ppolicy_forward_updates
              Specify that policy state changes that result from Bind
              operations (such as recording failures, lockout, etc.) on a
              consumer should be forwarded to a master instead of being
              written directly into the consumer's local database. This
              setting is only useful on a replication consumer, and also
              requires the updateref setting and chain overlay to be
              appropriately configured.

       ppolicy_hash_cleartext
              Specify that cleartext passwords present in Add and Modify
              requests should be hashed before being stored in the database.
              This violates the X.500/LDAP information model, but may be
              needed to compensate for LDAP clients that don't use the
              Password Modify extended operation to manage passwords.  It is
              recommended that when this option is used that compare, search,
              and read access be denied to all directory users.

       ppolicy_use_lockout
              A client will always receive an LDAP InvalidCredentials response
              when Binding to a locked account. By default, when a Password
              Policy control was provided on the Bind request, a Password
              Policy response will be included with no special error code set.
              This option changes the Password Policy response to include the
              AccountLocked error code. Note that sending the AccountLocked
              error code provides useful information to an attacker; sites
              that are sensitive to security issues should not enable this
              option.


OBJECT CLASS
       The ppolicy overlay depends on the pwdPolicy object class.  The
       definition of that class is as follows:

           (  1.3.6.1.4.1.42.2.27.8.2.1
               NAME 'pwdPolicy'
               AUXILIARY
               SUP top
               MUST ( pwdAttribute )
               MAY (
                   pwdMinAge $ pwdMaxAge $ pwdInHistory $
                   pwdCheckQuality $ pwdMinLength $
                   pwdExpireWarning $ pwdGraceAuthnLimit $
                   pwdLockout $ pwdLockoutDuration $
                   pwdMaxFailure $ pwdFailureCountInterval $
                   pwdMustChange $ pwdAllowUserChange $
                   pwdSafeModify ) )

       This implementation also provides an additional pwdPolicyChecker
       objectclass, used for password quality checking (see below).

           (  1.3.6.1.4.1.4754.2.99.1
               NAME 'pwdPolicyChecker'
               AUXILIARY
               SUP top
               MAY ( pwdCheckModule ) )

       Every account that should be subject to password policy control should
       have a pwdPolicySubentry attribute containing the DN of a valid
       pwdPolicy entry, or they can simply use the configured default.  In
       this way different users may be managed according to different
       policies.


OBJECT CLASS ATTRIBUTES
       Each one of the sections below details the meaning and use of a
       particular attribute of this pwdPolicy object class.

       pwdAttribute

       This attribute contains the name of the attribute to which the password
       policy is applied. For example, the password policy may be applied to
       the userPassword attribute.

       Note: in this implementation, the only value accepted for pwdAttribute
       is  userPassword .

           (  1.3.6.1.4.1.42.2.27.8.1.1
              NAME 'pwdAttribute'
              EQUALITY objectIdentifierMatch
              SYNTAX 1.3.6.1.4.1.1466.115.121.1.38 )

       pwdMinAge

       This attribute contains the number of seconds that must elapse between
       modifications allowed to the password. If this attribute is not
       present, zero seconds is assumed (i.e. the password may be modified
       whenever and however often is desired).

           (  1.3.6.1.4.1.42.2.27.8.1.2
              NAME 'pwdMinAge'
              EQUALITY integerMatch
              SYNTAX 1.3.6.1.4.1.1466.115.121.1.27
              SINGLE-VALUE )

       pwdMaxAge

       This attribute contains the number of seconds after which a modified
       password will expire.  If this attribute is not present, or if its
       value is zero (0), then passwords will not expire.

           (  1.3.6.1.4.1.42.2.27.8.1.3
              NAME 'pwdMaxAge'
              EQUALITY integerMatch
              SYNTAX 1.3.6.1.4.1.1466.115.121.1.27
              SINGLE-VALUE )

       pwdInHistory

       This attribute is used to specify the maximum number of used passwords
       that will be stored in the pwdHistory attribute.  If the pwdInHistory
       attribute is not present, or if its value is zero (0), used passwords
       will not be stored in pwdHistory and thus any previously-used password
       may be reused.  No history checking occurs if the password is being
       modified by the rootdn, although the password is saved in the history.

           (  1.3.6.1.4.1.42.2.27.8.1.4
              NAME 'pwdInHistory'
              EQUALITY integerMatch
              SYNTAX 1.3.6.1.4.1.1466.115.121.1.27
              SINGLE-VALUE )

       pwdCheckQuality

       This attribute indicates if and how password syntax will be checked
       while a password is being modified or added. If this attribute is not
       present, or its value is zero (0), no syntax checking will be done. If
       its value is one (1), the server will check the syntax, and if the
       server is unable to check the syntax, whether due to a client-side
       hashed password or some other reason, it will be accepted. If its value
       is two (2), the server will check the syntax, and if the server is
       unable to check the syntax it will return an error refusing the
       password.

           (  1.3.6.1.4.1.42.2.27.8.1.5
              NAME 'pwdCheckQuality'
              EQUALITY integerMatch
              SYNTAX 1.3.6.1.4.1.1466.115.121.1.27
              SINGLE-VALUE )

       pwdMinLength

       When syntax checking is enabled (see also the pwdCheckQuality
       attribute), this attribute contains the minimum number of characters
       that will be accepted in a password. If this attribute is not present,
       minimum password length is not enforced. If the server is unable to
       check the length of the password, whether due to a client-side hashed
       password or some other reason, the server will, depending on the value
       of pwdCheckQuality, either accept the password without checking it (if
       pwdCheckQuality is zero (0) or one (1)) or refuse it (if
       pwdCheckQuality is two (2)).

           (  1.3.6.1.4.1.42.2.27.8.1.6
              NAME 'pwdMinLength'
              EQUALITY integerMatch
              SYNTAX 1.3.6.1.4.1.1466.115.121.1.27
              SINGLE-VALUE )

       pwdExpireWarning

       This attribute contains the maximum number of seconds before a password
       is due to expire that expiration warning messages will be returned to a
       user who is authenticating to the directory.  If this attribute is not
       present, or if the value is zero (0), no warnings will be sent.

           (  1.3.6.1.4.1.42.2.27.8.1.7
              NAME 'pwdExpireWarning'
              EQUALITY integerMatch
              SYNTAX 1.3.6.1.4.1.1466.115.121.1.27
              SINGLE-VALUE )

       pwdGraceAuthnLimit

       This attribute contains the number of times that an expired password
       may be used to authenticate a user to the directory. If this attribute
       is not present or if its value is zero (0), users with expired
       passwords will not be allowed to authenticate to the directory.

           (  1.3.6.1.4.1.42.2.27.8.1.8
              NAME 'pwdGraceAuthnLimit'
              EQUALITY integerMatch
              SYNTAX 1.3.6.1.4.1.1466.115.121.1.27
              SINGLE-VALUE )

       pwdLockout

       This attribute specifies the action that should be taken by the
       directory when a user has made a number of failed attempts to
       authenticate to the directory.  If pwdLockout is set (its value is
       "TRUE"), the user will not be allowed to attempt to authenticate to the
       directory after there have been a specified number of consecutive
       failed bind attempts.  The maximum number of consecutive failed bind
       attempts allowed is specified by the pwdMaxFailure attribute.  If
       pwdLockout is not present, or if its value is "FALSE", the password may
       be used to authenticate no matter how many consecutive failed bind
       attempts have been made.

           (  1.3.6.1.4.1.42.2.27.8.1.9
              NAME 'pwdLockout'
              EQUALITY booleanMatch
              SYNTAX 1.3.6.1.4.1.1466.115.121.1.7
              SINGLE-VALUE )

       pwdLockoutDuration

       This attribute contains the number of seconds during which the password
       cannot be used to authenticate the user to the directory due to too
       many consecutive failed bind attempts.  (See also pwdLockout and
       pwdMaxFailure.)  If pwdLockoutDuration is not present, or if its value
       is zero (0), the password cannot be used to authenticate the user to
       the directory again until it is reset by an administrator.

           (  1.3.6.1.4.1.42.2.27.8.1.10
              NAME 'pwdLockoutDuration'
              EQUALITY integerMatch
              SYNTAX 1.3.6.1.4.1.1466.115.121.1.27
              SINGLE-VALUE )

       pwdMaxFailure

       This attribute contains the number of consecutive failed bind attempts
       after which the password may not be used to authenticate a user to the
       directory.  If pwdMaxFailure is not present, or its value is zero (0),
       then a user will be allowed to continue to attempt to authenticate to
       the directory, no matter how many consecutive failed bind attempts have
       occurred with that user's DN.  (See also pwdLockout and
       pwdLockoutDuration.)

           (  1.3.6.1.4.1.42.2.27.8.1.11
              NAME 'pwdMaxFailure'
              EQUALITY integerMatch
              SYNTAX 1.3.6.1.4.1.1466.115.121.1.27
              SINGLE-VALUE )

       pwdFailureCountInterval

       This attribute contains the number of seconds after which old
       consecutive failed bind attempts are purged from the failure counter,
       even though no successful authentication has occurred.  If
       pwdFailureCountInterval is not present, or its value is zero (0), the
       failure counter will only be reset by a successful authentication.

           (  1.3.6.1.4.1.42.2.27.8.1.12
              NAME 'pwdFailureCountInterval'
              EQUALITY integerMatch
              SYNTAX 1.3.6.1.4.1.1466.115.121.1.27
              SINGLE-VALUE )

       pwdMustChange

       This attribute specifies whether users must change their passwords when
       they first bind to the directory after a password is set or reset by
       the administrator, or not.  If pwdMustChange has a value of "TRUE",
       users must change their passwords when they first bind to the directory
       after a password is set or reset by the administrator.  If
       pwdMustChange is not present, or its value is "FALSE", users are not
       required to change their password upon binding after the administrator
       sets or resets the password.

           (  1.3.6.1.4.1.42.2.27.8.1.13
             NAME 'pwdMustChange'
             EQUALITY booleanMatch
             SYNTAX 1.3.6.1.4.1.1466.115.121.1.7
             SINGLE-VALUE )

       pwdAllowUserChange

       This attribute specifies whether users are allowed to change their own
       passwords or not.  If pwdAllowUserChange is set to "TRUE", or if the
       attribute is not present, users will be allowed to change their own
       passwords.  If its value is "FALSE", users will not be allowed to
       change their own passwords.

       Note: this implies that when pwdAllowUserChange is set to "TRUE", users
       will still be able to change the password of another user, subjected to
       access control.  This restriction only applies to modifications of
       ones's own password.  It should also be noted that pwdAllowUserChange
       was defined in the specification to provide rough access control to the
       password attribute in implementations that do not allow fine-grain
       access control.  Since OpenLDAP provides fine-grain access control, the
       use of this attribute is discouraged; ACLs should be used instead (see
       slapd.access(5) for details).

           (  1.3.6.1.4.1.42.2.27.8.1.14
              NAME 'pwdAllowUserChange'
              EQUALITY booleanMatch
              SYNTAX 1.3.6.1.4.1.1466.115.121.1.7
              SINGLE-VALUE )

       pwdSafeModify

       This attribute denotes whether the user's existing password must be
       sent along with their new password when changing a password.  If
       pwdSafeModify is set to "TRUE", the existing password must be sent
       along with the new password.  If the attribute is not present, or its
       value is "FALSE", the existing password need not be sent along with the
       new password.

           (  1.3.6.1.4.1.42.2.27.8.1.15
              NAME 'pwdSafeModify'
              EQUALITY booleanMatch
              SYNTAX 1.3.6.1.4.1.1466.115.121.1.7
              SINGLE-VALUE )

       pwdCheckModule

       This attribute names a user-defined loadable module that must
       instantiate the check_password() function.  This function will be
       called to further check a new password if pwdCheckQuality is set to one
       (1) or two (2), after all of the built-in password compliance checks
       have been passed.  This function will be called according to this
       function prototype:
           int check_password (char *pPasswd, char **ppErrStr, Entry *pEntry);
       The pPasswd parameter contains the clear-text user password, the
       ppErrStr parameter contains a double pointer that allows the function
       to return human-readable details about any error it encounters.  The
       optional pEntry parameter, if non-NULL, carries a pointer to the entry
       whose password is being checked.  If ppErrStr is NULL, then funcName
       must NOT attempt to use it/them.  A return value of LDAP_SUCCESS from
       the called function indicates that the password is ok, any other value
       indicates that the password is unacceptable.  If the password is
       unacceptable, the server will return an error to the client, and
       ppErrStr may be used to return a human-readable textual explanation of
       the error. The error string must be dynamically allocated as it will be
       free()'d by slapd.

           (  1.3.6.1.4.1.4754.1.99.1
              NAME 'pwdCheckModule'
              EQUALITY caseExactIA5Match
              SYNTAX 1.3.6.1.4.1.1466.115.121.1.26
              SINGLE-VALUE )

       Note: The user-defined loadable module named by pwdCheckModule must be
       in slapd's standard executable search PATH.

       Note: pwdCheckModule is a non-standard extension to the LDAP password
       policy proposal.


OPERATIONAL ATTRIBUTES
       The operational attributes used by the ppolicy module are stored in the
       user's entry.  Most of these attributes are not intended to be changed
       directly by users; they are there to track user activity.  They have
       been detailed here so that administrators and users can both understand
       the workings of the ppolicy module.


       Note that the current IETF Password Policy proposal does not define how
       these operational attributes are expected to behave in a replication
       environment. In general, authentication attempts on a slave server only
       affect the copy of the operational attributes on that slave and will
       not affect any attributes for a user's entry on the master server.
       Operational attribute changes resulting from authentication attempts on
       a master server will usually replicate to the slaves (and also
       overwrite any changes that originated on the slave).  These behaviors
       are not guaranteed and are subject to change when a formal
       specification emerges.

       userPassword

       The userPassword attribute is not strictly part of the ppolicy module.
       It is, however, the attribute that is tracked and controlled by the
       module.  Please refer to the standard OpenLDAP schema for its
       definition.

       pwdPolicySubentry

       This attribute refers directly to the pwdPolicy subentry that is to be
       used for this particular directory user.  If pwdPolicySubentry exists,
       it must contain the DN of a valid pwdPolicy object.  If it does not
       exist, the ppolicy module will enforce the default password policy
       rules on the user associated with this authenticating DN. If there is
       no default, or the referenced subentry does not exist, then no policy
       rules will be enforced.

           (  1.3.6.1.4.1.42.2.27.8.1.23
              NAME 'pwdPolicySubentry'
              DESC 'The pwdPolicy subentry in effect for
                  this object'
              EQUALITY distinguishedNameMatch
              SYNTAX 1.3.6.1.4.1.1466.115.121.1.12
              SINGLE-VALUE
              NO-USER-MODIFICATION
              USAGE directoryOperation)

       pwdChangedTime

       This attribute denotes the last time that the entry's password was
       changed.  This value is used by the password expiration policy to
       determine whether the password is too old to be allowed to be used for
       user authentication.  If pwdChangedTime does not exist, the user's
       password will not expire.

           (  1.3.6.1.4.1.42.2.27.8.1.16
              NAME 'pwdChangedTime'
              DESC 'The time the password was last changed'
              SYNTAX 1.3.6.1.4.1.1466.115.121.1.24
              EQUALITY generalizedTimeMatch
              ORDERING generalizedTimeOrderingMatch
              SINGLE-VALUE
              NO-USER-MODIFICATION
              USAGE directoryOperation)

       pwdAccountLockedTime

       This attribute contains the time that the user's account was locked.
       If the account has been locked, the password may no longer be used to
       authenticate the user to the directory.  If pwdAccountLockedTime is set
       to 000001010000Z, the user's account has been permanently locked and
       may only be unlocked by an administrator. Note that account locking
       only takes effect when the pwdLockout password policy attribute is set
       to "TRUE".

           (  1.3.6.1.4.1.42.2.27.8.1.17
              NAME 'pwdAccountLockedTime'
              DESC 'The time an user account was locked'
              SYNTAX 1.3.6.1.4.1.1466.115.121.1.24
              EQUALITY generalizedTimeMatch
              ORDERING generalizedTimeOrderingMatch
              SINGLE-VALUE
              NO-USER-MODIFICATION
              USAGE directoryOperation)

       pwdFailureTime

       This attribute contains the timestamps of each of the consecutive
       authentication failures made upon attempted authentication to this DN
       (i.e. account).  If too many timestamps accumulate here (refer to the
       pwdMaxFailure password policy attribute for details), and the
       pwdLockout password policy attribute is set to "TRUE", the account may
       be locked.  (Please also refer to the pwdLockout password policy
       attribute.)  Excess timestamps beyond those allowed by pwdMaxFailure
       may also be purged.  If a successful authentication is made to this DN
       (i.e. to this user account), then pwdFailureTime will be cleansed of
       entries.

           (  1.3.6.1.4.1.42.2.27.8.1.19
              NAME 'pwdFailureTime'
              DESC 'The timestamps of the last consecutive
                  authentication failures'
              SYNTAX 1.3.6.1.4.1.1466.115.121.1.24
              EQUALITY generalizedTimeMatch
              ORDERING generalizedTimeOrderingMatch
              NO-USER-MODIFICATION
              USAGE directoryOperation )

       pwdHistory

       This attribute contains the history of previously used passwords for
       this DN (i.e. for this user account).  The values of this attribute are
       stored in string format as follows:


           pwdHistory=
               time "#" syntaxOID "#" length "#" data

           time=
               GeneralizedTime as specified in section 3.3.13 of [RFC4517]


           syntaxOID = numericoid
               This is the string representation of the dotted-decimal OID
               that defines the syntax used to store the password.  numericoid
               is described in section 1.4 of [RFC4512].

           length = NumericString
               The number of octets in the data.  NumericString is described
               in section 3.3.23 of [RFC4517].

           data =
               Octets representing the password in the format specified by
               syntaxOID.


       This format allows the server to store and transmit a history of
       passwords that have been used.  In order for equality matching on the
       values in this attribute to function properly, the time field is in GMT
       format.

           (  1.3.6.1.4.1.42.2.27.8.1.20
              NAME 'pwdHistory'
              DESC 'The history of user passwords'
              SYNTAX 1.3.6.1.4.1.1466.115.121.1.40
              EQUALITY octetStringMatch
              NO-USER-MODIFICATION
              USAGE directoryOperation)

       pwdGraceUseTime This attribute contains the list of timestamps of
       logins made after the user password in the DN has expired.  These post-
       expiration logins are known as "grace logins".  If too many grace
       logins have been used (please refer to the pwdGraceLoginLimit password
       policy attribute), then the DN will no longer be allowed to be used to
       authenticate the user to the directory until the administrator changes
       the DN's userPassword attribute.

           (  1.3.6.1.4.1.42.2.27.8.1.21
              NAME 'pwdGraceUseTime'
              DESC 'The timestamps of the grace login once the password has
           expired'
              SYNTAX 1.3.6.1.4.1.1466.115.121.1.24
              EQUALITY generalizedTimeMatch
              NO-USER-MODIFICATION
              USAGE directoryOperation)

       pwdReset

       This attribute indicates whether the user's password has been reset by
       the administrator and thus must be changed upon first use of this DN
       for authentication to the directory.  If pwdReset is set to "TRUE",
       then the password was reset and the user must change it upon first
       authentication.  If the attribute does not exist, or is set to "FALSE",
       the user need not change their password due to administrative reset.

           (  1.3.6.1.4.1.42.2.27.8.1.22
              NAME 'pwdReset'
              DESC 'The indication that the password has
                  been reset'
              EQUALITY booleanMatch
              SYNTAX 1.3.6.1.4.1.1466.115.121.1.7
              SINGLE-VALUE
              USAGE directoryOperation)


EXAMPLES
              database bdb
              suffix dc=example,dc=com
              ...
              overlay ppolicy
              ppolicy_default "cn=Standard,ou=Policies,dc=example,dc=com"


SEE ALSO
       ldap(3), slapd.conf(5), slapd-config(5), slapo-chain(5).

       "OpenLDAP Administrator's Guide" (http://www.OpenLDAP.org/doc/admin/)

       IETF LDAP password policy proposal by P. Behera, L.  Poitou and J.
       Sermersheim:  documented in IETF document "draft-behera-ldap-password-
       policy-09.txt".


BUGS
       The LDAP Password Policy specification is not yet an approved standard,
       and it is still evolving. This code will continue to be in flux until
       the specification is finalized.


ACKNOWLEDGEMENTS
       This module was written in 2004 by Howard Chu of Symas Corporation with
       significant input from Neil Dunbar and Kartik Subbarao of Hewlett-
       Packard.

       This manual page borrows heavily and shamelessly from the specification
       upon which the password policy module it describes is based.  This
       source is the IETF LDAP password policy proposal by P. Behera, L.
       Poitou and J. Sermersheim.  The proposal is fully documented in the
       IETF document named draft-behera-ldap-password-policy-09.txt, written
       in July of 2005.

       OpenLDAP Software is developed and maintained by The OpenLDAP Project
       <http://www.openldap.org/>.  OpenLDAP Software is derived from
       University of Michigan LDAP 3.3 Release.



OpenLDAP 2.4.40                   2014/09/20                  SLAPO_PPOLICY(5)