Auth_context.ClientSourceSee V1.Client.init
Without setting addrs on the auth context, you can't encode/decode messages. Thus, you don't get back a t. However, you can still use the ap_req as a way for the client to claim its identity.
Read an AP_REP message from the server. This authenticates the server to the client
val make_krb_cred :
t ->
forwardable:bool ->
client:Principal.t ->
Cred_cache.t ->
Krb_cred.t Async.Deferred.Or_error.tCreate a KRB-CRED message. This will be sent by the client to forward its credentials (really just TGT) to the server.