About the isMemberOf and isDirectMemberOf virtual attribute
PingDirectory server can generate either isMemberOf or isDirectMemberOf virtual attributes in user entries.
The existence of static, nested, dynamic, and virtual static groups can make it complex to work with groups in the server because the ways you interact with them are so different. Static groups can use three different structural object classes, not counting the auxiliary class for virtual static groups, which can further complicate things. PingDirectory server’s virtual attributes simplify the group-related determination process for consistency across all types of groups.
The value of the isMemberOf virtual attribute is a list of distinguished names (DNs) of all groups, including static, nested, dynamic, and virtual static groups, in which the associated user is a member. The value of the isDirectMemberOf virtual attribute is a subset of the values of isMemberOf, which represents the groups for which the entry is an explicit or direct member. Both are enabled by default.
Because isMemberOf and isDirectMemberOf are operational attributes, only users who have been granted the privilege can see them. The default set of access control rules do not allow any level of access to user data. The only access that is granted is what is included in user-defined access control rules, which is generally given to a uid=admin administrator account. You should restrict access to operational and non-operational attributes to the minimal set of users that need to see them. The root bind DN, cn=Directory Manager, has the privilege to view operational attributes by default.
The rewrite-search-filters isMemberOf configuration property
The rewrite-search-filters property allows isMemberOf searches targeting dynamic groups to be processed more efficiently because you can substitute the filter of the dynamic group into the original search filter. This speeds up paged searches across a large dynamic group.
The following table shows the three possible settings for the rewrite-search-filters.
| Setting | Description | ||
|---|---|---|---|
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Always enhance search filters to include the dynamic group filter components.
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The default value. Enhances search filters to include dynamic group filter components only when the base DN and scope of the dynamic group.
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Never enhance search filters to include the dynamic group filter components. |
To use the rewrite-search-filters configuration property:
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To set the
rewrite-search-filtersconfiguration property to the desired setting, rundsconfig.dsconfig set-virtual-attribute-prop --name isMemberOf --set rewrite-search-filters:<always | never | within-group-scope>
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To optionally keep the server from archiving configurations where only this attribute is changing, you can declare the
rewrite-search-filterattribute as insignificant by runningdsconfig.dsconfig set-backend-prop --backend-name config --add insignificant-config-archive-attribute:ds-cfg-rewrite-search-filters
Determine if a user is a member of a specified group
To determine if a user is a member of a specified group using the isMemberOf virtual attribute, perform a base-level search against the user’s entry with an equality filter targeting the isMemberOf attribute with a value that is the DN of the target group. The following table illustrates this base-level search.
| Search Parameter | Value |
|---|---|
Base DN |
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Scope |
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Filter |
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Requested Attributes |
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If this search returns an entry, then the user is a member of the specified group. If no entry is returned, then the user is not a member of the given group.
Determine the set of all groups in which a user is a member
To determine the set of all groups in which a user is a member, retrieve the user’s entry with a base-level search and include the isMemberOf attribute.
| Search Parameter | Value |
|---|---|
Base DN |
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Scope |
|
Filter |
|
Requested attributes |
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Determine the set of all members for a specified group
To determine the set of all members for a specified group, issue a subtree search with an equality filter targeting the isMemberOf attribute with a value that is the DN of the target group and requesting the attributes you wish to have for member entries.
| Search Parameter | Value |
|---|---|
Base DN |
|
Scope |
|
Filter |
|
Requested Attributes |
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The isDirectMemberOf virtual attribute can be used in the previous examples in place of isMemberOf if you only need to find groups that users are an actual member of. You must use isMemberOf for nested group membership.
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If this filter targets a dynamic group using an unindexed search, then this might be an expensive operation. However, it is not more expensive than retrieving the target group and then issuing a search based on information contained in the member URL. |
For static groups, this approach has the added benefit of using a single search to retrieve information from all user entries. Otherwise, it would be required to retrieve the static group and then perform a separate search for each member’s entry.