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LDAP_SERVER_VERIFY_NAME_OID control code

The LDAP_SERVER_VERIFY_NAME_OID control is used with extended LDAP add and modify requests to instruct the DC accepting the update which DC it should verify with, the existence of any DN attribute values.

To use this control, set the members of the LDAPControl structure as follows:

PWCHAR ldctl_oid = LDAP_SERVER_VERIFY_NAME_OID;
struct berval ldctl_value;
BOOLEAN ldctl_iscritical;

Members

ldctl_oid

A pointer to a wide, null-terminated string, LDAP_SERVER_VERIFY_NAME_OID, which is defined as "1.2.840.113556.1.4.1338".

ldctl_value

Specifies a BER-encoded sequence of parameters that enables the application to specify a server to verify the existence of an object. In the berval structure, set bv_val to a pointer to the sequence that contains the flag and server name data and set bv_len to the length of the sequence. For more information, see the Remarks section.

ldctl_iscritical

Can be TRUE or FALSE depending on whether the extended search function is critical to your application.

Remarks

The Verify Name control is used with ldap_modify_ext or ldap_add_ext to specify the specific server used to verify the existence of an object. The ldctl_value field is set to the following BER-encoded sequence:

Sequence {
  Flags        INTEGER
  ServerName   OCTET STRING \\Unicode server string
}

The ber_printf function is used to create the sequence data. The flags portion is set to 0, and the ServerName is a Unicode string that contains the fully qualified DNS name of the server to contact for verification.

When a DN valued attribute is updated with new values, the DC on which the update occurs verifies that an object with the new DN exists somewhere in the forest. The DC will first verify that the object is held locally, and failing that, the DC will find a GC and ask the GC if it knows about an object with the new DN.

Applications will sometimes need to create an object and at the same time update an attribute on another existing object to add a reference to the newly created object. If both object are on same DC, the application can create the new object and then modify the second object attribute, adding a reference to the first object, without having to consider replication update times.

However, if the two objects are in different domains and therefore held on two different DCs, when the application attempts to modify the attribute of the second object to add a reference to the first newly created object, it is impossible for the application to recognize that sufficient time has passed for the newly created object to replicate to the GC used by the second object. The LDAP_SERVER_VERIFY_NAME_OID control enables the application to specify the DN of the newly created object so the verification, performed by the attribute update call of the second object, does not fail due to replication update lag.

Requirements

Minimum supported client
Windows Vista
Minimum supported server
Windows Server 2008
Header
Ntldap.h

See also

Using Controls