%%%----------------------------------------------------------------------
%%% File : ejabberd_auth_anonymous.erl
%%% Author : Mickael Remond <mickael.remond@process-one.net>
%%% Purpose : Anonymous feature support in ejabberd
%%% Created : 17 Feb 2006 by Mickael Remond <mremond@process-one.net>
%%%
%%%
%%% ejabberd, Copyright (C) 2002-2008 Process-one
%%%
%%% 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., 59 Temple Place, Suite 330, Boston, MA
%%% 02111-1307 USA
%%%
%%%----------------------------------------------------------------------
-module(ejabberd_auth_anonymous).
-author('mickael.remond@process-one.net').
-export([start/1,
allow_anonymous/1,
is_sasl_anonymous_enabled/1,
is_login_anonymous_enabled/1,
anonymous_user_exist/2,
allow_multiple_connections/1,
register_connection/3,
unregister_connection/3
]).
%% Function used by ejabberd_auth:
-export([login/2,
set_password/3,
check_password/3,
check_password/5,
try_register/3,
dirty_get_registered_users/0,
get_vh_registered_users/1,
get_password/2,
get_password/3,
is_user_exists/2,
remove_user/2,
remove_user/3,
plain_password_required/0]).
-include("ejabberd.hrl").
-include("jlib.hrl").
-record(anonymous, {us, sid}).
%% Create the anonymous table if at least one virtual host has anonymous features enabled
%% Register to login / logout events
start(Host) ->
%% TODO: Check cluster mode
mnesia:create_table(anonymous, [{ram_copies, [node()]},
{type, bag},
{attributes, record_info(fields, anonymous)}]),
%% The hooks are needed to add / remove users from the anonymous tables
ejabberd_hooks:add(sm_register_connection_hook, Host,
?MODULE, register_connection, 100),
ejabberd_hooks:add(sm_remove_connection_hook, Host,
?MODULE, unregister_connection, 100),
ok.
%% Return true if anonymous is allowed for host or false otherwise
allow_anonymous(Host) ->
lists:member(?MODULE, ejabberd_auth:auth_modules(Host)).
%% Return true if anonymous mode is enabled and if anonymous protocol is SASL
%% anonymous protocol can be: sasl_anon|login_anon|both
is_sasl_anonymous_enabled(Host) ->
case allow_anonymous(Host) of
false -> false;
true ->
case anonymous_protocol(Host) of
sasl_anon -> true;
both -> true;
_Other -> false
end
end.
%% Return true if anonymous login is enabled on the server
%% anonymous login can be use using standard authentication method (i.e. with
%% clients that do not support anonymous login)
is_login_anonymous_enabled(Host) ->
case allow_anonymous(Host) of
false -> false;
true ->
case anonymous_protocol(Host) of
login_anon -> true;
both -> true;
_Other -> false
end
end.
%% Return the anonymous protocol to use: sasl_anon|login_anon|both
%% defaults to login_anon
anonymous_protocol(Host) ->
case ejabberd_config:get_local_option({anonymous_protocol, Host}) of
sasl_anon -> sasl_anon;
login_anon -> login_anon;
both -> both;
_Other -> sasl_anon
end.
%% Return true if multiple connections have been allowed in the config file
%% defaults to false
allow_multiple_connections(Host) ->
case ejabberd_config:get_local_option({allow_multiple_connections, Host}) of
true -> true;
_Other -> false
end.
%% Check if user exist in the anonymus database
anonymous_user_exist(User, Server) ->
LUser = jlib:nodeprep(User),
LServer = jlib:nameprep(Server),
US = {LUser, LServer},
case catch mnesia:dirty_read({anonymous, US}) of
[] ->
false;
[_H|_T] ->
true
end.
%% Remove connection from Mnesia tables
remove_connection(SID, LUser, LServer) ->
US = {LUser, LServer},
F = fun() ->
mnesia:delete_object({anonymous, US, SID})
end,
mnesia:transaction(F).
%% Register connection
register_connection(SID, #jid{luser = LUser, lserver = LServer}, Info) ->
AuthModule = xml:get_attr_s(auth_module, Info),
case AuthModule == ?MODULE of
true ->
US = {LUser, LServer},
mnesia:sync_dirty(
fun() -> mnesia:write(#anonymous{us = US, sid=SID})
end);
false ->
ok
end.
%% Remove an anonymous user from the anonymous users table
unregister_connection(SID, #jid{luser = LUser, lserver = LServer}, _) ->
purge_hook(anonymous_user_exist(LUser, LServer),
LUser, LServer),
remove_connection(SID, LUser, LServer).
%% Launch the hook to purge user data only for anonymous users
purge_hook(false, _LUser, _LServer) ->
ok;
purge_hook(true, LUser, LServer) ->
ejabberd_hooks:run(anonymous_purge_hook, LServer, [LUser, LServer]).
%% ---------------------------------
%% Specific anonymous auth functions
%% ---------------------------------
%% When anonymous login is enabled, check the password for permenant users
%% before allowing access
check_password(User, Server, Password) ->
check_password(User, Server, Password, undefined, undefined).
check_password(User, Server, _Password, _StreamID, _Digest) ->
%% We refuse login for registered accounts (They cannot logged but
%% they however are "reserved")
case ejabberd_auth:is_user_exists_in_other_modules(?MODULE,
User, Server) of
true -> false;
false -> login(User, Server)
end.
login(User, Server) ->
case is_login_anonymous_enabled(Server) of
false -> false;
true ->
case anonymous_user_exist(User, Server) of
%% Reject the login if an anonymous user with the same login
%% is already logged and if multiple login has not been enable
%% in the config file.
true -> allow_multiple_connections(Server);
%% Accept login and add user to the anonymous table
false -> true
end
end.
%% When anonymous login is enabled, check that the user is permanent before
%% changing its password
set_password(User, Server, _Password) ->
case anonymous_user_exist(User, Server) of
true ->
ok;
false ->
{error, not_allowed}
end.
%% When anonymous login is enabled, check if permanent users are allowed on
%% the server:
try_register(_User, _Server, _Password) ->
{error, not_allowed}.
dirty_get_registered_users() ->
[].
get_vh_registered_users(_Server) ->
[].
%% Return password of permanent user or false for anonymous users
get_password(User, Server) ->
get_password(User, Server, "").
get_password(User, Server, DefaultValue) ->
case anonymous_user_exist(User, Server) of
%% We return the default value if the user is anonymous
true ->
DefaultValue;
%% We return the permanent user password otherwise
false ->
false
end.
%% Returns true if the user exists in the DB or if an anonymous user is logged
%% under the given name
is_user_exists(User, Server) ->
anonymous_user_exist(User, Server).
remove_user(_User, _Server) ->
{error, not_allowed}.
remove_user(_User, _Server, _Password) ->
not_allowed.
plain_password_required() ->
false.
