# Module Rpc_auth_sys

    module Rpc_auth_sys: sig .. end

Authentication module AUTH_SYS

This module implements system authentication (AUTH_SYS, also known as AUTH_UNIX).

*********************************************************************** WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING!

This authentication method is insecure because it does not use any verifier. I strongly dissuade everybody from using this authentication method for newly written RPC systems. I include it here only for compatibility with older systems.

WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! ***********************************************************************

    type identity = [ `Effective_user | `Real_user | `This_user of int * int * int array * string ]

Specifies the user:

- ``Effective_user`: Take the effective user of the process
- ``Real_user`: Take the real user of the process
- ``This_user(uid,gid,sup_groups,hostname)`: Pretend to be this user

    val client_auth_method : ?identity:identity -> unit -> Rpc_client.auth_method

Pass the result of this function to `Rpc_client.set_auth_methods` to configure client authentication.

`identity`: As whom the clients authenticates.

    type user_name_format = [ `Custom of int32 -> int32 -> int32 array -> string -> string | `Full | `UID ]

How `Rpc_server.get_user` returns the user as string:

- ``Full`: The format includes all transmitted details: `"<uid>.<gid>.<gid1>.<gid2>...@<hostname>"`. All user and group IDs are numeric. The first two numbers, <uid> and <gid> are always present. The other numbers are the supplementary group IDs and can be omitted. The <hostname> is the name passed in the credentials.
- ``UID`: The string is the numeric user ID
- ``Custom f`: The string is returned by the function `f`. The arguments are `uid`, `gid`, the array of the supplementary group IDs and the hostname.

    val server_auth_method : ?lookup_hostname:bool ->
           ?require_privileged_port:bool ->
           ?user_name_as:user_name_format -> unit -> Rpc_server.auth_method

Pass the result of this function to `Rpc_server.set_auth_methods` to configure authentication.

`lookup_hostname`: if true, the hostname contained in the credentials is checked (by gethostbyname)

`require_privileged_port`: if true, the client must use a privileged port. Note that Unix domain sockets are rejected in this mode.

User name strings as formatted as specified by `user_name_as`. This defaults to ``Full`.

    val parse_user_name : string -> int * int * int array * string

Parses a user name as returned by `Rpc_server.get_user` in conjunction with the AUTH_SYS authentication and ``Full` formatting. Returns `(uid,gid,sup_groups,hostname)`.1