%%%----------------------------------------------------------------------
%%% File : ejabberd_router.erl
%%% Author : Alexey Shchepin <alexey@process-one.net>
%%% Purpose : Main router
%%% Created : 27 Nov 2002 by Alexey Shchepin <alexey@process-one.net>
%%%
%%%
%%% ejabberd, Copyright (C) 2002-2022 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(ejabberd_router).
-author('alexey@process-one.net').
-ifndef(GEN_SERVER).
-define(GEN_SERVER, gen_server).
-endif.
-behaviour(?GEN_SERVER).
%% API
-export([route/1,
route_error/2,
route_iq/2,
route_iq/3,
route_iq/4,
register_route/2,
register_route/3,
register_route/4,
register_routes/1,
host_of_route/1,
process_iq/1,
unregister_route/1,
unregister_route/2,
unregister_routes/1,
get_all_routes/0,
is_my_route/1,
is_my_host/1,
clean_cache/1,
config_reloaded/0,
get_backend/0]).
-export([start_link/0]).
-export([init/1, handle_call/3, handle_cast/2,
handle_info/2, terminate/2, code_change/3]).
%% Deprecated functions
-export([route/3, route_error/4]).
-deprecated([{route, 3}, {route_error, 4}]).
%% This value is used in SIP and Megaco for a transaction lifetime.
-define(IQ_TIMEOUT, 32000).
-define(CALL_TIMEOUT, timer:minutes(10)).
-include("logger.hrl").
-include("ejabberd_router.hrl").
-include_lib("xmpp/include/xmpp.hrl").
-include("ejabberd_stacktrace.hrl").
-callback init() -> any().
-callback register_route(binary(), binary(), local_hint(),
undefined | pos_integer(), pid()) -> ok | {error, term()}.
-callback unregister_route(binary(), undefined | pos_integer(), pid()) -> ok | {error, term()}.
-callback find_routes(binary()) -> {ok, [#route{}]} | {error, any()}.
-callback get_all_routes() -> {ok, [binary()]} | {error, any()}.
-record(state, {route_monitors = #{} :: #{{binary(), pid()} => reference()}}).
%%====================================================================
%% API
%%====================================================================
start_link() ->
?GEN_SERVER:start_link({local, ?MODULE}, ?MODULE, [], []).
-spec route(stanza()) -> ok.
route(Packet) ->
try do_route(Packet)
catch ?EX_RULE(Class, Reason, St) ->
StackTrace = ?EX_STACK(St),
?ERROR_MSG("Failed to route packet:~n~ts~n** ~ts",
[xmpp:pp(Packet),
misc:format_exception(2, Class, Reason, StackTrace)])
end.
-spec route(jid(), jid(), xmlel() | stanza()) -> ok.
route(#jid{} = From, #jid{} = To, #xmlel{} = El) ->
try xmpp:decode(El, ?NS_CLIENT, [ignore_els]) of
Pkt -> route(From, To, Pkt)
catch _:{xmpp_codec, Why} ->
?ERROR_MSG("Failed to decode xml element ~p when "
"routing from ~ts to ~ts: ~ts",
[El, jid:encode(From), jid:encode(To),
xmpp:format_error(Why)])
end;
route(#jid{} = From, #jid{} = To, Packet) ->
route(xmpp:set_from_to(Packet, From, To)).
-spec route_error(stanza(), stanza_error()) -> ok.
route_error(Packet, Err) ->
Type = xmpp:get_type(Packet),
if Type == error; Type == result ->
ok;
true ->
route(xmpp:make_error(Packet, Err))
end.
%% Route the error packet only if the originating packet is not an error itself.
%% RFC3920 9.3.1
-spec route_error(jid(), jid(), xmlel(), xmlel()) -> ok;
(jid(), jid(), stanza(), stanza_error()) -> ok.
route_error(From, To, #xmlel{} = ErrPacket, #xmlel{} = OrigPacket) ->
#xmlel{attrs = Attrs} = OrigPacket,
case <<"error">> == fxml:get_attr_s(<<"type">>, Attrs) of
false -> route(From, To, ErrPacket);
true -> ok
end;
route_error(From, To, Packet, #stanza_error{} = Err) ->
Type = xmpp:get_type(Packet),
if Type == error; Type == result ->
ok;
true ->
route(From, To, xmpp:make_error(Packet, Err))
end.
-spec route_iq(iq(), fun((iq() | timeout) -> any())) -> ok.
route_iq(IQ, Fun) ->
route_iq(IQ, Fun, undefined, ?IQ_TIMEOUT).
-spec route_iq(iq(), term(), pid() | atom()) -> ok.
route_iq(IQ, State, Proc) ->
route_iq(IQ, State, Proc, ?IQ_TIMEOUT).
-spec route_iq(iq(), term(), pid() | atom(), undefined | non_neg_integer()) -> ok.
route_iq(IQ, State, Proc, undefined) ->
route_iq(IQ, State, Proc, ?IQ_TIMEOUT);
route_iq(IQ, State, Proc, Timeout) ->
ejabberd_iq:route(IQ, Proc, State, Timeout).
-spec register_route(binary(), binary()) -> ok.
register_route(Domain, ServerHost) ->
register_route(Domain, ServerHost, undefined).
-spec register_route(binary(), binary(), local_hint() | undefined) -> ok.
register_route(Domain, ServerHost, LocalHint) ->
register_route(Domain, ServerHost, LocalHint, self()).
-spec register_route(binary(), binary(), local_hint() | undefined, pid()) -> ok.
register_route(Domain, ServerHost, LocalHint, Pid) ->
case {jid:nameprep(Domain), jid:nameprep(ServerHost)} of
{error, _} ->
erlang:error({invalid_domain, Domain});
{_, error} ->
erlang:error({invalid_domain, ServerHost});
{LDomain, LServerHost} ->
Mod = get_backend(),
case Mod:register_route(LDomain, LServerHost, LocalHint,
get_component_number(LDomain), Pid) of
ok ->
?DEBUG("Route registered: ~ts", [LDomain]),
monitor_route(LDomain, Pid),
ejabberd_hooks:run(route_registered, [LDomain]),
delete_cache(Mod, LDomain);
{error, Err} ->
?ERROR_MSG("Failed to register route ~ts: ~p",
[LDomain, Err])
end
end.
-spec register_routes([{binary(), binary()}]) -> ok.
register_routes(Domains) ->
lists:foreach(fun ({Domain, ServerHost}) -> register_route(Domain, ServerHost)
end,
Domains).
-spec unregister_route(binary()) -> ok.
unregister_route(Domain) ->
unregister_route(Domain, self()).
-spec unregister_route(binary(), pid()) -> ok.
unregister_route(Domain, Pid) ->
case jid:nameprep(Domain) of
error ->
erlang:error({invalid_domain, Domain});
LDomain ->
Mod = get_backend(),
case Mod:unregister_route(
LDomain, get_component_number(LDomain), Pid) of
ok ->
?DEBUG("Route unregistered: ~ts", [LDomain]),
demonitor_route(LDomain, Pid),
ejabberd_hooks:run(route_unregistered, [LDomain]),
delete_cache(Mod, LDomain);
{error, Err} ->
?ERROR_MSG("Failed to unregister route ~ts: ~p",
[LDomain, Err])
end
end.
-spec unregister_routes([binary()]) -> ok.
unregister_routes(Domains) ->
lists:foreach(fun (Domain) -> unregister_route(Domain)
end,
Domains).
-spec find_routes(binary()) -> [#route{}].
find_routes(Domain) ->
Mod = get_backend(),
case use_cache(Mod) of
true ->
case ets_cache:lookup(
?ROUTES_CACHE, {route, Domain},
fun() ->
case Mod:find_routes(Domain) of
{ok, Rs} when Rs /= [] ->
{ok, Rs};
_ ->
error
end
end) of
{ok, Rs} -> Rs;
error -> []
end;
false ->
case Mod:find_routes(Domain) of
{ok, Rs} -> Rs;
_ -> []
end
end.
-spec get_all_routes() -> [binary()].
get_all_routes() ->
Mod = get_backend(),
case use_cache(Mod) of
true ->
case ets_cache:lookup(
?ROUTES_CACHE, routes,
fun() ->
case Mod:get_all_routes() of
{ok, Rs} when Rs /= [] ->
{ok, Rs};
_ ->
error
end
end) of
{ok, Rs} -> Rs;
error -> []
end;
false ->
case Mod:get_all_routes() of
{ok, Rs} -> Rs;
_ -> []
end
end.
-spec host_of_route(binary()) -> binary().
host_of_route(Domain) ->
case jid:nameprep(Domain) of
error ->
erlang:error({invalid_domain, Domain});
LDomain ->
case find_routes(LDomain) of
[#route{server_host = ServerHost}|_] ->
ServerHost;
_ ->
erlang:error({unregistered_route, Domain})
end
end.
-spec is_my_route(binary()) -> boolean().
is_my_route(Domain) ->
case jid:nameprep(Domain) of
error ->
erlang:error({invalid_domain, Domain});
LDomain ->
find_routes(LDomain) /= []
end.
-spec is_my_host(binary()) -> boolean().
is_my_host(Domain) ->
case jid:nameprep(Domain) of
error ->
erlang:error({invalid_domain, Domain});
LDomain ->
case find_routes(LDomain) of
[#route{server_host = LDomain}|_] -> true;
_ -> false
end
end.
-spec process_iq(iq()) -> any().
process_iq(IQ) ->
gen_iq_handler:handle(IQ).
-spec config_reloaded() -> ok.
config_reloaded() ->
Mod = get_backend(),
init_cache(Mod).
%%====================================================================
%% gen_server callbacks
%%====================================================================
init([]) ->
ejabberd_hooks:add(config_reloaded, ?MODULE, config_reloaded, 50),
Mod = get_backend(),
init_cache(Mod),
Mod:init(),
clean_cache(),
{ok, #state{}}.
handle_call({monitor, Domain, Pid}, _From, State) ->
MRefs = State#state.route_monitors,
MRefs1 = case maps:is_key({Domain, Pid}, MRefs) of
true -> MRefs;
false ->
MRef = erlang:monitor(process, Pid),
MRefs#{{Domain, Pid} => MRef}
end,
{reply, ok, State#state{route_monitors = MRefs1}};
handle_call({demonitor, Domain, Pid}, _From, State) ->
MRefs = State#state.route_monitors,
MRefs1 = case maps:find({Domain, Pid}, MRefs) of
{ok, MRef} ->
erlang:demonitor(MRef, [flush]),
maps:remove({Domain, Pid}, MRefs);
error ->
MRefs
end,
{reply, ok, State#state{route_monitors = MRefs1}};
handle_call(Request, From, State) ->
?WARNING_MSG("Unexpected call from ~p: ~p", [From, Request]),
{noreply, State}.
handle_cast(Msg, State) ->
?WARNING_MSG("Unexpected cast: ~p", [Msg]),
{noreply, State}.
handle_info({route, Packet}, State) ->
route(Packet),
{noreply, State};
handle_info({'DOWN', MRef, _, Pid, Info}, State) ->
MRefs = maps:filter(
fun({Domain, P}, M) when P == Pid, M == MRef ->
?DEBUG("Process ~p with route registered to ~ts "
"has terminated unexpectedly with reason: ~p",
[P, Domain, Info]),
try unregister_route(Domain, Pid)
catch _:_ -> ok
end,
false;
(_, _) ->
true
end, State#state.route_monitors),
{noreply, State#state{route_monitors = MRefs}};
handle_info(Info, State) ->
?ERROR_MSG("Unexpected info: ~p", [Info]),
{noreply, State}.
terminate(_Reason, _State) ->
ejabberd_hooks:delete(config_reloaded, ?MODULE, config_reloaded, 50).
code_change(_OldVsn, State, _Extra) ->
{ok, State}.
%%--------------------------------------------------------------------
%%% Internal functions
%%--------------------------------------------------------------------
-spec do_route(stanza()) -> ok.
do_route(OrigPacket) ->
?DEBUG("Route:~n~ts", [xmpp:pp(OrigPacket)]),
case ejabberd_hooks:run_fold(filter_packet, OrigPacket, []) of
drop ->
ok;
Packet ->
case ejabberd_iq:dispatch(Packet) of
true ->
ok;
false ->
To = xmpp:get_to(Packet),
LDstDomain = To#jid.lserver,
case find_routes(LDstDomain) of
[] ->
ejabberd_s2s:route(Packet);
[Route] ->
do_route(Packet, Route);
Routes ->
From = xmpp:get_from(Packet),
balancing_route(From, To, Packet, Routes)
end,
ok
end
end.
-spec do_route(stanza(), #route{}) -> any().
do_route(Pkt, #route{local_hint = LocalHint,
pid = Pid}) when is_pid(Pid) ->
case LocalHint of
{apply, Module, Function} when node(Pid) == node() ->
Module:Function(Pkt);
_ ->
ejabberd_cluster:send(Pid, {route, Pkt})
end;
do_route(_Pkt, _Route) ->
ok.
-spec balancing_route(jid(), jid(), stanza(), [#route{}]) -> any().
balancing_route(From, To, Packet, Rs) ->
case get_domain_balancing(From, To, To#jid.lserver) of
undefined ->
Value = erlang:system_time(),
case [R || R <- Rs, node(R#route.pid) == node()] of
[] ->
R = lists:nth(erlang:phash2(Value, length(Rs))+1, Rs),
do_route(Packet, R);
LRs ->
R = lists:nth(erlang:phash2(Value, length(LRs))+1, LRs),
do_route(Packet, R)
end;
Value ->
SRs = lists:ukeysort(#route.local_hint, Rs),
R = lists:nth(erlang:phash2(Value, length(SRs))+1, SRs),
do_route(Packet, R)
end.
-spec get_component_number(binary()) -> pos_integer() | undefined.
get_component_number(LDomain) ->
M = ejabberd_option:domain_balancing(),
case maps:get(LDomain, M, undefined) of
undefined -> undefined;
Opts -> maps:get(component_number, Opts)
end.
-spec get_domain_balancing(jid(), jid(), binary()) -> integer() | ljid() | undefined.
get_domain_balancing(From, To, LDomain) ->
M = ejabberd_option:domain_balancing(),
case maps:get(LDomain, M, undefined) of
undefined -> undefined;
Opts ->
case maps:get(type, Opts, random) of
random -> erlang:system_time();
source -> jid:tolower(From);
destination -> jid:tolower(To);
bare_source -> jid:remove_resource(jid:tolower(From));
bare_destination -> jid:remove_resource(jid:tolower(To))
end
end.
-spec monitor_route(binary(), pid()) -> ok.
monitor_route(Domain, Pid) ->
?GEN_SERVER:call(?MODULE, {monitor, Domain, Pid}, ?CALL_TIMEOUT).
-spec demonitor_route(binary(), pid()) -> ok.
demonitor_route(Domain, Pid) ->
case whereis(?MODULE) == self() of
true ->
ok;
false ->
?GEN_SERVER:call(?MODULE, {demonitor, Domain, Pid}, ?CALL_TIMEOUT)
end.
-spec get_backend() -> module().
get_backend() ->
DBType = ejabberd_option:router_db_type(),
list_to_existing_atom("ejabberd_router_" ++ atom_to_list(DBType)).
-spec cache_nodes(module()) -> [node()].
cache_nodes(Mod) ->
case erlang:function_exported(Mod, cache_nodes, 0) of
true -> Mod:cache_nodes();
false -> ejabberd_cluster:get_nodes()
end.
-spec use_cache(module()) -> boolean().
use_cache(Mod) ->
case erlang:function_exported(Mod, use_cache, 0) of
true -> Mod:use_cache();
false -> ejabberd_option:router_use_cache()
end.
-spec delete_cache(module(), binary()) -> ok.
delete_cache(Mod, Domain) ->
case use_cache(Mod) of
true ->
ets_cache:delete(?ROUTES_CACHE, {route, Domain}, cache_nodes(Mod)),
ets_cache:delete(?ROUTES_CACHE, routes, cache_nodes(Mod));
false ->
ok
end.
-spec init_cache(module()) -> ok.
init_cache(Mod) ->
case use_cache(Mod) of
true ->
ets_cache:new(?ROUTES_CACHE, cache_opts());
false ->
ets_cache:delete(?ROUTES_CACHE)
end.
-spec cache_opts() -> [proplists:property()].
cache_opts() ->
MaxSize = ejabberd_option:router_cache_size(),
CacheMissed = ejabberd_option:router_cache_missed(),
LifeTime = ejabberd_option:router_cache_life_time(),
[{max_size, MaxSize}, {cache_missed, CacheMissed}, {life_time, LifeTime}].
-spec clean_cache(node()) -> non_neg_integer().
clean_cache(Node) ->
ets_cache:filter(
?ROUTES_CACHE,
fun(_, error) ->
false;
(routes, _) ->
false;
({route, _}, {ok, Rs}) ->
not lists:any(
fun(#route{pid = Pid}) ->
node(Pid) == Node
end, Rs)
end).
-spec clean_cache() -> ok.
clean_cache() ->
ejabberd_cluster:eval_everywhere(?MODULE, clean_cache, [node()]).
