%%%---------------------------------------------------------------------- %%% File : mod_ping.erl %%% Author : Brian Cully %%% Purpose : Support XEP-0199 XMPP Ping and periodic keepalives %%% Created : 11 Jul 2009 by Brian Cully %%% %%% %%% ejabberd, Copyright (C) 2002-2013 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., 59 Temple Place, Suite 330, Boston, MA %%% 02111-1307 USA %%% %%%---------------------------------------------------------------------- -module(mod_ping). -author('bjc@kublai.com'). -behavior(gen_mod). -behavior(gen_server). -include("ejabberd.hrl"). -include("logger.hrl"). -include("jlib.hrl"). -define(SUPERVISOR, ejabberd_sup). -define(DEFAULT_SEND_PINGS, false). -define(DEFAULT_PING_INTERVAL, 60). -define(DICT, dict). %% API -export([start_link/2, start_ping/2, stop_ping/2]). %% gen_mod callbacks -export([start/2, stop/1]). %% gen_server callbacks -export([init/1, terminate/2, handle_call/3, handle_cast/2, handle_info/2, code_change/3]). %% Hook callbacks -export([iq_ping/3, user_online/3, user_offline/3, user_send/3]). -record(state, {host = <<"">>, send_pings = ?DEFAULT_SEND_PINGS :: boolean(), ping_interval = ?DEFAULT_PING_INTERVAL :: non_neg_integer(), timeout_action = none :: none | kill, timers = (?DICT):new() :: dict()}). %%==================================================================== %% API %%==================================================================== start_link(Host, Opts) -> Proc = gen_mod:get_module_proc(Host, ?MODULE), gen_server:start_link({local, Proc}, ?MODULE, [Host, Opts], []). start_ping(Host, JID) -> Proc = gen_mod:get_module_proc(Host, ?MODULE), gen_server:cast(Proc, {start_ping, JID}). stop_ping(Host, JID) -> Proc = gen_mod:get_module_proc(Host, ?MODULE), gen_server:cast(Proc, {stop_ping, JID}). %%==================================================================== %% gen_mod callbacks %%==================================================================== start(Host, Opts) -> Proc = gen_mod:get_module_proc(Host, ?MODULE), PingSpec = {Proc, {?MODULE, start_link, [Host, Opts]}, transient, 2000, worker, [?MODULE]}, supervisor:start_child(?SUPERVISOR, PingSpec). stop(Host) -> Proc = gen_mod:get_module_proc(Host, ?MODULE), gen_server:call(Proc, stop), supervisor:delete_child(?SUPERVISOR, Proc). %%==================================================================== %% gen_server callbacks %%==================================================================== init([Host, Opts]) -> SendPings = gen_mod:get_opt(send_pings, Opts, fun(B) when is_boolean(B) -> B end, ?DEFAULT_SEND_PINGS), PingInterval = gen_mod:get_opt(ping_interval, Opts, fun(I) when is_integer(I), I>0 -> I end, ?DEFAULT_PING_INTERVAL), TimeoutAction = gen_mod:get_opt(timeout_action, Opts, fun(none) -> none; (kill) -> kill end, none), IQDisc = gen_mod:get_opt(iqdisc, Opts, fun gen_iq_handler:check_type/1, no_queue), mod_disco:register_feature(Host, ?NS_PING), gen_iq_handler:add_iq_handler(ejabberd_sm, Host, ?NS_PING, ?MODULE, iq_ping, IQDisc), gen_iq_handler:add_iq_handler(ejabberd_local, Host, ?NS_PING, ?MODULE, iq_ping, IQDisc), case SendPings of true -> ejabberd_hooks:add(sm_register_connection_hook, Host, ?MODULE, user_online, 100), ejabberd_hooks:add(sm_remove_connection_hook, Host, ?MODULE, user_offline, 100), ejabberd_hooks:add(user_send_packet, Host, ?MODULE, user_send, 100); _ -> ok end, {ok, #state{host = Host, send_pings = SendPings, ping_interval = PingInterval, timeout_action = TimeoutAction, timers = (?DICT):new()}}. terminate(_Reason, #state{host = Host}) -> ejabberd_hooks:delete(sm_remove_connection_hook, Host, ?MODULE, user_offline, 100), ejabberd_hooks:delete(sm_register_connection_hook, Host, ?MODULE, user_online, 100), ejabberd_hooks:delete(user_send_packet, Host, ?MODULE, user_send, 100), gen_iq_handler:remove_iq_handler(ejabberd_local, Host, ?NS_PING), gen_iq_handler:remove_iq_handler(ejabberd_sm, Host, ?NS_PING), mod_disco:unregister_feature(Host, ?NS_PING). handle_call(stop, _From, State) -> {stop, normal, ok, State}; handle_call(_Req, _From, State) -> {reply, {error, badarg}, State}. handle_cast({start_ping, JID}, State) -> Timers = add_timer(JID, State#state.ping_interval, State#state.timers), {noreply, State#state{timers = Timers}}; handle_cast({stop_ping, JID}, State) -> Timers = del_timer(JID, State#state.timers), {noreply, State#state{timers = Timers}}; handle_cast({iq_pong, JID, timeout}, State) -> Timers = del_timer(JID, State#state.timers), ejabberd_hooks:run(user_ping_timeout, State#state.host, [JID]), case State#state.timeout_action of kill -> #jid{user = User, server = Server, resource = Resource} = JID, case ejabberd_sm:get_session_pid(User, Server, Resource) of Pid when is_pid(Pid) -> ejabberd_c2s:stop(Pid); _ -> ok end; _ -> ok end, {noreply, State#state{timers = Timers}}; handle_cast(_Msg, State) -> {noreply, State}. handle_info({timeout, _TRef, {ping, JID}}, State) -> IQ = #iq{type = get, sub_el = [#xmlel{name = <<"ping">>, attrs = [{<<"xmlns">>, ?NS_PING}], children = []}]}, Pid = self(), F = fun (Response) -> gen_server:cast(Pid, {iq_pong, JID, Response}) end, From = jlib:make_jid(<<"">>, State#state.host, <<"">>), ejabberd_local:route_iq(From, JID, IQ, F), Timers = add_timer(JID, State#state.ping_interval, State#state.timers), {noreply, State#state{timers = Timers}}; handle_info(_Info, State) -> {noreply, State}. code_change(_OldVsn, State, _Extra) -> {ok, State}. %%==================================================================== %% Hook callbacks %%==================================================================== iq_ping(_From, _To, #iq{type = Type, sub_el = SubEl} = IQ) -> case {Type, SubEl} of {get, #xmlel{name = <<"ping">>}} -> IQ#iq{type = result, sub_el = []}; _ -> IQ#iq{type = error, sub_el = [SubEl, ?ERR_FEATURE_NOT_IMPLEMENTED]} end. user_online(_SID, JID, _Info) -> start_ping(JID#jid.lserver, JID). user_offline(_SID, JID, _Info) -> stop_ping(JID#jid.lserver, JID). user_send(JID, _From, _Packet) -> start_ping(JID#jid.lserver, JID). %%==================================================================== %% Internal functions %%==================================================================== add_timer(JID, Interval, Timers) -> LJID = jlib:jid_tolower(JID), NewTimers = case (?DICT):find(LJID, Timers) of {ok, OldTRef} -> cancel_timer(OldTRef), (?DICT):erase(LJID, Timers); _ -> Timers end, TRef = erlang:start_timer(Interval * 1000, self(), {ping, JID}), (?DICT):store(LJID, TRef, NewTimers). del_timer(JID, Timers) -> LJID = jlib:jid_tolower(JID), case (?DICT):find(LJID, Timers) of {ok, TRef} -> cancel_timer(TRef), (?DICT):erase(LJID, Timers); _ -> Timers end. cancel_timer(TRef) -> case erlang:cancel_timer(TRef) of false -> receive {timeout, TRef, _} -> ok after 0 -> ok end; _ -> ok end.