slapo-constraint(5) — Linux manual page


SLAPO-CONSTRAINT(5)        File Formats Manual       SLAPO-CONSTRAINT(5)

NAME         top

       slapo-constraint - Attribute Constraint Overlay to slapd

SYNOPSIS         top


DESCRIPTION         top

       The constraint overlay is used to ensure that attribute values
       match some constraints beyond basic LDAP syntax.  Attributes can
       have multiple constraints placed upon them, and all must be
       satisfied when modifying an attribute value under constraint.

       This overlay is intended to be used to force syntactic regularity
       upon certain string represented data which have well known
       canonical forms, like telephone numbers, post codes, FQDNs, etc.

       It constrains only LDAP add, modify and rename commands and only
       seeks to control the add and replace values of modify and rename

       No constraints are applied for operations performed with the
       relax control set.


       This slapd.conf option applies to the constraint overlay.  It
       should appear after the overlay directive.

       constraint_attribute <attribute_name>[,...] <type> <value>
       [<extra> [...]]
              Specifies the constraint which should apply to the comma-
              separated attribute list named as the first parameter.
              Five types of constraint are currently supported - regex,
              size, count, uri, and set.

              The parameter following the regex type is a Unix style
              regular expression (See regex(7) ). The parameter
              following the uri type is an LDAP URI. The URI will be
              evaluated using an internal search.  It must not include a
              hostname, and it must include a list of attributes to

              The parameter following the set type is a string that is
              interpreted according to the syntax in use for ACL sets.
              This allows one to construct constraints based on the
              contents of the entry.

              The size type can be used to enforce a limit on an
              attribute length, and the count type limits the number of
              values of an attribute.

              Extra parameters can occur in any order after those
              described above.

              <extra> : restrict=<uri>

              This extra parameter allows one to restrict the
              application of the corresponding constraint only to
              entries that match the base, scope and filter portions of
              the LDAP URI.  The base, if present, must be within the
              naming context of the database.  The scope is only used
              when the base is present; it defaults to base.  The other
              parameters of the URI are not allowed.

       Any attempt to add or modify an attribute named as part of the
       constraint overlay specification which does not fit the
       constraint listed will fail with a LDAP_CONSTRAINT_VIOLATION

EXAMPLES         top

              overlay constraint
              constraint_attribute jpegPhoto size 131072
              constraint_attribute userPassword count 3
              constraint_attribute mail regex ^[[:alnum:]]$
              constraint_attribute title uri
              constraint_attribute cn,sn,givenName set
                "(this/givenName + [ ] + this/sn) & this/cn"

       A specification like the above would reject any mail attribute
       which did not look like <alpha-numeric string>  It
       would also reject any title attribute whose values were not
       listed in the title attribute of any titleCatalog entries in the
       given scope. (Note that the "dc=catalog,dc=example,dc=com"
       subtree ought to reside in a separate database, otherwise the
       initial set of titleCatalog entries could not be populated while
       the constraint is in effect.)  Finally, it requires the values of
       the attribute cn to be constructed by pairing values of the
       attributes sn and givenName, separated by a space, but only for
       entries derived from the objectClass inetOrgPerson.

FILES         top

              default slapd configuration file

SEE ALSO         top

       slapd.conf(5), slapd-config(5),


       This module was written in 2005 by Neil Dunbar of Hewlett-Packard
       and subsequently extended by Howard Chu and Emmanuel Dreyfus.
       OpenLDAP Software is developed and maintained by The OpenLDAP
       Project <>.  OpenLDAP Software is derived
       from the University of Michigan LDAP 3.3 Release.

COLOPHON         top

       This page is part of the OpenLDAP (an open source implementation
       of the Lightweight Directory Access Protocol) project.
       Information about the project can be found at 
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       manual page, see ⟨⟩.  This page was
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Pages that refer to this page: slapd.overlays(5)