V0.ServiceSourcetype 'a with_init_args =
Principal.t ->
[ `Keytab of Keytab.t | `User_to_user of Keyblock.t ] ->
ap_req:Ap_req.t ->
'aRead the KRB_AP_REQ. To decrypt, either look for a key in the supplied keytab, or use the supplied keyblock. Return the client's principal.