2.2.5 WMI Filter Search

The WMI Filter Search message uses LDAP as a transport. The message allows the client to query the Group Policy server for filters using a WQL Query (as specified in [MS-WMI] section 2.2.1) that additionally constrain the set of GPOs that Group Policy extensions SHOULD<6> use.

An LDAP SearchRequest MUST be sent to the Group Policy server with the following parameters.

 Parameter

 Value

baseObject

CN=<WMI FILTER ID>,CN=SOM,CN=WMIPolicy,CN=System, <LDAP DN for the root of the domain>

where <WMI FILTER ID> is the identifier of the WMI filter, and <LDAP DN for the root of the domain> is the DN of the root of the domain where the filter is defined. The <LDAP DN for the root of the domain> is an input parameter referenced from the Policy Target Domain DN ADM element.

scope

MUST be the base object (0).

derefAliases

MUST be set to 0 (neverDerefAliases).

sizeLimit

No limit is set (this MUST be set to 0).

timeLimit

MUST be set to 0 (infinite).

typesOnly

MUST be set to 0 (FALSE).

filter

The following LDAP filter (using the representation as specified in [RFC2254]) MUST be used:

(objectclass=*)

attributes

The following attribute names are passed as inputs to the LDAP search request: msWMI-ID, msWMI-Name, msWMI-Parm1, msWMI-Author, msWMI-ChangeDate, msWMI-CreationDate, and msWMI-Parm2.

The client receives a reply from the search request from the Group Policy server with one or more LDAP searchResponse messages. Those messages MUST contain one or more searchResultEntries. Those searchResultEntries MUST contain an objectName DN attribute that is the WMI filter named by that DN. The searchResultEntry also MUST contain an attributes field with the values in Active Directory for the attributes of the WMI filter object that were searched for. The attributes MUST have the following formats.

 Attribute

 Format

msWMI-ID

GUID.

msWMI-Name

Directory string that gives a human-friendly name that an administrator defines.

msWMI-Parm1

Directory string that gives a human-friendly description of the filter's purpose that an administrator defines.

msWMI-Author

Directory string that gives the name of the author of the WMI filter.

msWMI-ChangeDate

A field in date-time format that indicates when the filter was last updated.

msWMI-CreationDate

A field in date-time format that indicates when the filter was created.

msWMI-Parm2

Directory string that contains the WMI Query Language (WQL) query for a WQL query to be executed on the client.