3.3.5.6.4.2 PAC_CLIENT_INFO Structure
The KDC populates the returned PAC_CLIENT_INFO structure ([MS-PAC] section 2.7) fields as follows:
The ClientId field is the Kerberos initial ticket-granting ticket (TGT) authentication time ([RFC4120] section 5.3).
The NameLength field is the length of the Name field, in bytes.
The Name field is set to cname.