%%%----------------------------------------------------------------------
%%% File : extauth.erl
%%% Author : Leif Johansson <leifj@it.su.se>
%%% Purpose : External authentication using a simple port-driver
%%% Created : 30 Jul 2004 by Leif Johansson <leifj@it.su.se>
%%%
%%%
%%% ejabberd, Copyright (C) 2002-2017 ProcessOne
%%%
%%% This program is free software; you can redistribute it and/or
%%% modify it under the terms of the GNU General Public License as
%%% published by the Free Software Foundation; either version 2 of the
%%% License, or (at your option) any later version.
%%%
%%% This program is distributed in the hope that it will be useful,
%%% but WITHOUT ANY WARRANTY; without even the implied warranty of
%%% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
%%% General Public License for more details.
%%%
%%% You should have received a copy of the GNU General Public License along
%%% with this program; if not, write to the Free Software Foundation, Inc.,
%%% 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
%%%
%%%----------------------------------------------------------------------
-module(extauth).
-behaviour(ejabberd_config).
-author('leifj@it.su.se').
-export([start/2, stop/1, init/2, check_password/3,
set_password/3, try_register/3, remove_user/2,
remove_user/3, is_user_exists/2, opt_type/1]).
-include("ejabberd.hrl").
-include("logger.hrl").
-define(INIT_TIMEOUT, 60000).
-define(CALL_TIMEOUT, 10000).
start(Host, ExtPrg) ->
lists:foreach(fun (This) ->
start_instance(get_process_name(Host, This), ExtPrg)
end,
lists:seq(0, get_instances(Host) - 1)).
start_instance(ProcessName, ExtPrg) ->
spawn(?MODULE, init, [ProcessName, ExtPrg]).
restart_instance(ProcessName, ExtPrg) ->
unregister(ProcessName),
start_instance(ProcessName, ExtPrg).
init(ProcessName, ExtPrg) ->
register(ProcessName, self()),
process_flag(trap_exit, true),
Port = open_port({spawn, ExtPrg}, [{packet, 2}]),
loop(Port, ?INIT_TIMEOUT, ProcessName, ExtPrg).
stop(Host) ->
lists:foreach(fun (This) ->
get_process_name(Host, This) ! stop
end,
lists:seq(0, get_instances(Host) - 1)).
get_process_name(Host, Integer) ->
gen_mod:get_module_proc(iolist_to_binary([Host,
integer_to_list(Integer)]),
eauth).
check_password(User, Server, Password) ->
call_port(Server, [<<"auth">>, User, Server, Password]).
is_user_exists(User, Server) ->
call_port(Server, [<<"isuser">>, User, Server]).
set_password(User, Server, Password) ->
call_port(Server, [<<"setpass">>, User, Server, Password]).
try_register(User, Server, Password) ->
case call_port(Server,
[<<"tryregister">>, User, Server, Password])
of
true -> ok;
false -> {error, not_allowed}
end.
remove_user(User, Server) ->
call_port(Server, [<<"removeuser">>, User, Server]).
remove_user(User, Server, Password) ->
call_port(Server,
[<<"removeuser3">>, User, Server, Password]).
call_port(Server, Msg) ->
LServer = jid:nameprep(Server),
ProcessName = get_process_name(LServer,
random_instance(get_instances(LServer))),
ProcessName ! {call, self(), Msg},
receive {eauth, Result} -> Result end.
random_instance(MaxNum) ->
randoms:uniform(MaxNum) - 1.
get_instances(Server) ->
ejabberd_config:get_option({extauth_instances, Server}, 1).
loop(Port, Timeout, ProcessName, ExtPrg) ->
receive
{call, Caller, Msg} ->
port_command(Port, encode(Msg)),
receive
{Port, {data, Data}} ->
?DEBUG("extauth call '~p' received data response:~n~p",
[Msg, Data]),
Caller ! {eauth, decode(Data)},
loop(Port, ?CALL_TIMEOUT, ProcessName, ExtPrg);
{Port, Other} ->
?ERROR_MSG("extauth call '~p' received strange response:~n~p",
[Msg, Other]),
Caller ! {eauth, false},
loop(Port, ?CALL_TIMEOUT, ProcessName, ExtPrg)
after Timeout ->
?ERROR_MSG("extauth call '~p' didn't receive response",
[Msg]),
Caller ! {eauth, false},
Pid = restart_instance(ProcessName, ExtPrg),
flush_buffer_and_forward_messages(Pid),
exit(port_terminated)
end;
stop ->
Port ! {self(), close},
receive {Port, closed} -> exit(normal) end;
{'EXIT', Port, Reason} ->
?CRITICAL_MSG("extauth script has exitted abruptly "
"with reason '~p'",
[Reason]),
Pid = restart_instance(ProcessName, ExtPrg),
flush_buffer_and_forward_messages(Pid),
exit(port_terminated)
end.
flush_buffer_and_forward_messages(Pid) ->
receive
Message ->
Pid ! Message, flush_buffer_and_forward_messages(Pid)
after 0 -> true
end.
encode(L) -> str:join(L, <<":">>).
decode([0, 0]) -> false;
decode([0, 1]) -> true.
-spec opt_type(extauth_instances) -> fun((pos_integer()) -> pos_integer());
(atom()) -> [atom()].
opt_type(extauth_instances) ->
fun (V) when is_integer(V), V > 0 -> V end;
opt_type(_) -> [extauth_instances].
