Test_mode.ServerSourceval serve :
authorize:Authorize.t ->
principal:Principal.Name.t ->
client_addr:Async.Socket.Address.Inet.t ->
protocol_backend ->
(Connection.t,
[ `Krb_error of Core.Error.t
| `Handshake_error of Handshake_error.t
| `Rejected_client ])
Async.Deferred.Result.t