Defining Targets

should verify that they target the correct entries and attributes by using the same filter in an ldapsearch operation.

3.2.5. Targeting Attribute Values Using LDAP Filters

You can use access control to target specific attribute values. This means that you can grant or deny permissions on an attribute if that attribute's value meets the criteria defined in the ACI. An ACI that grants or denies access based on an attribute's value is called a value-based ACI.

For example, you might grant all users in your organization permission to modify the nsroledn attribute in their own entry. However, you would also want to ensure that they do not give themselves certain key roles, such as Top Level Administrator. LDAP filters are used to check that the conditions on attribute values are satisfied.

To create a value-based ACI, you must use the targattrfilters keyword with the following syntax:

(targattrfilters="add=attr1:F1 && attr2:F2... && attrn:Fn,del=attr1:F1 &&

attr2:F2 ... && attrn:Fn")

add represents the operation of creating an attribute.

del represents the operation of deleting an attribute.

attrx represents the target attributes.

Fx represents filters that apply only to the associated attribute.

When creating an entry, if a filter applies to an attribute in the new entry, then each instance of that attribute must satisfy the filter. When deleting an entry, if a filter applies to an attribute in the entry, then each instance of that attribute must also satisfy the filter.

When modifying an entry, if the operation adds an attribute, then the add filter that applies to that attribute must be satisfied; if the operation deletes an attribute, then the delete filter that applies to that attribute must be satisfied. If individual values of an attribute already present in the entry are replaced, then both the add and delete filters must be satisfied.

For example, consider the following attribute filter:

(targattrfilters="add=nsroledn:(!(nsroledn=cn=superAdmin)) &&

telephoneNumber:(telephoneNumber=123*)")

This filter can be used to allow users to add any role (nsroledn attribute) to their own entry,

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HP UX Red Hat Direry Server Software manual Targeting Attribute Values Using Ldap Filters