slapo-dynlist(5) File Formats Manual slapo-dynlist(5)
NAME
slapo-dynlist - Dynamic List overlay to slapd
SYNOPSIS
/opt/local/etc/openldap/slapd.conf
DESCRIPTION
The dynlist overlay to slapd(8) allows expansion of dynamic lists and
groups. Any time an entry with a specific objectClass (defined in the
overlay configuration) is being returned, the LDAP URI-valued
occurrences of a specific attribute (also defined in the overlay
configuration) are expanded into the corresponding entries.
For a dynamic list, the values of the attributes listed in the URI are
added from the matching entries to the original entry. No recursion is
allowed, to avoid potential infinite loops. The resulting entry must
comply with the LDAP data model, so constraints are enforced. For
example, if a SINGLE-VALUE attribute is listed, only the first value
found during the list expansion appears in the final entry.
For a dynamic group, the DNs of the matching entries are added to a
member attribute in the original entry.
All dynamic behavior is disabled when the manageDSAit control (RFC
3296) is used. In that case, the contents of the original entry is
returned; namely, the URLs are returned instead of being expanded.
CONFIGURATION
The config directives that are specific to the dynlist overlay must be
prefixed by dynlist-, to avoid potential conflicts with directives
specific to the underlying database or to other stacked overlays.
overlay dynlist
This directive adds the dynlist overlay to the current database,
or to the frontend, if used before any database instantiation;
see slapd.conf(5) for details.
This slapd.conf configuration option is defined for the dynlist
overlay. It may have multiple occurrences, and it must appear after the
overlay directive.
dynlist-attrset <group-oc> [<URI>] <URL-ad> [options]
The value group-oc is the name of the objectClass that triggers
the dynamic expansion of the data.
The optional URI restricts expansion only to entries matching
the DN, the scope and the filter portions of the URI.
The value URL-ad is the name of the attributeDescription that
contains the URI that is expanded by the overlay; if none is
present, no expansion occurs. If the intersection of the
attributes requested by the search operation (or the asserted
attribute for compares) and the attributes listed in the URI is
empty, no expansion occurs for that specific URI. It must be a
subtype of labeledURI.
The remaining options depend on whether a dynamic list or a
dynamic group is being configured.
For a dynamic list, the allowed options have the form
[<mapped-ad>:<list-ad> ...]
The mapped-ad can be used to remap attributes obtained through
expansion. The list-ad must be one of the attributes returned
in the expansion of the URIs in the URL-ad attribute of the
dynamic entry. Multiple mapping statements can be used. Note
that in order for dynamic lists to be usable in a search filter,
the dynamic attributes to be filtered must be explicitly mapped.
They can be mapped to themselves if no transformation is
required.
For a dynamic group, the allowed options are
<member-ad>[+<memberOf-ad>[@<static-oc>[*]]]
The member-ad is required; this attribute will list the DN of
the entries resulting from the internal search. In this case,
the attrs portion of the URIs in the URL-ad attribute must be
absent, and the DNs of all the entries resulting from the
expansion of the URIs are listed as values of this attribute.
Compares that assert the value of the member-ad attribute of
entries with group-oc objectClass apply as if the DN of the
entries resulting from the expansion of the URI were present in
the group-oc entry as values of the member-ad attribute. If the
optional memberOf-ad attribute is also specified, then it will
be populated with the DNs of the dynamic groups that an entry is
a member of. If the optional static-oc objectClass is also
specified, then the memberOf attribute will also be populated
with the DNs of the static groups that an entry is a member of.
Note that using the same static-oc objectClass in more than one
dynamic group configuration is not supported. If the optional *
character is also specified, then the member and memberOf values
will be populated recursively, for nested groups. Note that
currently nesting is only supported for Search operations, not
Compares.
dynlist-simple TRUE | FALSE
This option downgrades to the behavior of the OpenLDAP 2.4
dynlist overlay. It disables memberOf processing, nested group
support, and filter evaluation of dynamically generated values.
The default is FALSE.
The dynlist overlay may be used with any backend, but it is mainly
intended for use with local storage backends. In case the URI
expansion is very resource-intensive and occurs frequently with well-
defined patterns, one should consider adding a proxycache later on in
the overlay stack.
AUTHORIZATION
By default the expansions are performed using the identity of the
current LDAP user. This identity may be overridden by setting the
dgIdentity attribute in the group's entry to the DN of another LDAP
user. In that case the dgIdentity will be used when expanding the URIs
in the object. Setting the dgIdentity to a zero-length string will
cause the expansions to be performed anonymously. Note that the
dgIdentity attribute is defined in the dyngroup schema, and this schema
must be loaded before the dgIdentity authorization feature may be used.
If the dgAuthz attribute is also present in the group's entry, its
values are used to determine what identities are authorized to use the
dgIdentity to expand the group. Values of the dgAuthz attribute must
conform to the (experimental) OpenLDAP authz syntax. When using
dynamic memberOf in search filters, search access to the entryDN
pseudo-attribute is required.
EXAMPLE
This example collects all the email addresses of a database into a
single entry; first of all, make sure that slapd.conf contains the
directives:
include /path/to/dyngroup.schema
# ...
database <database>
# ...
overlay dynlist
dynlist-attrset groupOfURLs memberURL
and that slapd loads dynlist.la, if compiled as a run-time module; then
add to the database an entry like
dn: cn=Dynamic List,ou=Groups,dc=example,dc=com
objectClass: groupOfURLs
cn: Dynamic List
memberURL: ldap:///ou=People,dc=example,dc=com?mail?sub?(objectClass=person)
If no <attrs> are provided in the URI, all (non-operational) attributes
are collected.
The values of the above list can not be evaluated in a search filter.
To enable filter evaluation on the dynamic list, the configuration must
be changed to explicitly map the dynamic attributes to be filtered. In
this case mail is just mapped to itself.
include /path/to/dyngroup.schema
# ...
database <database>
# ...
overlay dynlist
dynlist-attrset groupOfURLs memberURL mail:mail
This example implements the dynamic group feature on the member
attribute:
include /path/to/dyngroup.schema
# ...
database <database>
# ...
overlay dynlist
dynlist-attrset groupOfURLs memberURL member
A dynamic group with dgIdentity authorization could be created with an
entry like
dn: cn=Dynamic Group,ou=Groups,dc=example,dc=com
objectClass: groupOfURLs
objectClass: dgIdentityAux
cn: Dynamic Group
memberURL: ldap:///ou=People,dc=example,dc=com??sub?(objectClass=person)
dgIdentity: cn=Group Proxy,ou=Services,dc=example,dc=com
This example extends the dynamic group feature to add a dynamic
dgMemberOf attribute to all the members of a dynamic group:
include /path/to/dyngroup.schema
# ...
database <database>
# ...
overlay dynlist
dynlist-attrset groupOfURLs memberURL member+dgMemberOf
This example extends the dynamic memberOf feature to add the memberOf
attribute to all the members of both static and dynamic groups:
include /path/to/dyngroup.schema
# ...
database <database>
# ...
overlay dynlist
dynlist-attrset groupOfURLs memberURL member+memberOf@groupOfNames
This dynamic memberOf feature can fully replace the functionality of
the slapo-memberof(5) overlay.
FILES
/opt/local/etc/openldap/slapd.conf
default slapd configuration file
BACKWARD COMPATIBILITY
The dynlist overlay has been reworked with the 2.5 release to use a
consistent namespace as with other overlays. As a side-effect the
following cn=config parameters are deprecated and will be removed in a
future release: olcDlAttrSet is replaced with olcDynListAttrSet
olcDynamicList is replaced with olcDynListConfig
SEE ALSO
slapo-dynlist(5) overlay
supports dynamic configuration via back-config.
BUGS
Filtering on dynamic groups may return incomplete results if the search
operation uses the pagedResults control.
ACKNOWLEDGEMENTS
This module was written in 2004 by Pierangelo Masarati for SysNet
s.n.c.
Attribute remapping was contributed in 2008 by Emmanuel Dreyfus.
OpenLDAP 2.6.10 2025/05/22 slapo-dynlist(5)
openldap 2.6.10 - Generated Sun May 25 11:09:00 CDT 2025