%%%------------------------------------------------------------------- %%% File : mod_delegation.erl %%% Author : Anna Mukharram <amuhar3@gmail.com> %%% Purpose : XEP-0355: Namespace Delegation %%% %%% %%% ejabberd, Copyright (C) 2002-2018 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(mod_delegation). -author('amuhar3@gmail.com'). -protocol({xep, 0355, '0.3'}). -behaviour(gen_server). -behaviour(gen_mod). %% API -export([start/2, stop/1, reload/3, mod_opt_type/1, depends/2, mod_options/1]). %% gen_server callbacks -export([init/1, handle_call/3, handle_cast/2, handle_info/2, terminate/2, code_change/3]). -export([component_connected/1, component_disconnected/2, ejabberd_local/1, ejabberd_sm/1, decode_iq_subel/1, disco_local_features/5, disco_sm_features/5, disco_local_identity/5, disco_sm_identity/5]). -include("logger.hrl"). -include("xmpp.hrl"). -type disco_acc() :: {error, stanza_error()} | {result, [binary()]} | empty. -record(state, {server_host = <<"">> :: binary(), delegations = dict:new() :: dict:dict()}). -type state() :: #state{}. %%%=================================================================== %%% API %%%=================================================================== start(Host, Opts) -> gen_mod:start_child(?MODULE, Host, Opts). stop(Host) -> gen_mod:stop_child(?MODULE, Host). reload(_Host, _NewOpts, _OldOpts) -> ok. mod_opt_type(namespaces) -> fun(L) -> lists:map( fun({NS, Opts}) -> Attrs = proplists:get_value(filtering, Opts, []), Access = proplists:get_value(access, Opts, none), {NS, Attrs, Access} end, L) end. mod_options(_Host) -> [{namespaces, []}]. depends(_, _) -> []. -spec decode_iq_subel(xmpp_element() | xmlel()) -> xmpp_element() | xmlel(). %% Tell gen_iq_handler not to auto-decode IQ payload decode_iq_subel(El) -> El. -spec component_connected(binary()) -> ok. component_connected(Host) -> lists:foreach( fun(ServerHost) -> Proc = gen_mod:get_module_proc(ServerHost, ?MODULE), gen_server:cast(Proc, {component_connected, Host}) end, ejabberd_config:get_myhosts()). -spec component_disconnected(binary(), binary()) -> ok. component_disconnected(Host, _Reason) -> lists:foreach( fun(ServerHost) -> Proc = gen_mod:get_module_proc(ServerHost, ?MODULE), gen_server:cast(Proc, {component_disconnected, Host}) end, ejabberd_config:get_myhosts()). -spec ejabberd_local(iq()) -> iq(). ejabberd_local(IQ) -> process_iq(IQ, ejabberd_local). -spec ejabberd_sm(iq()) -> iq(). ejabberd_sm(IQ) -> process_iq(IQ, ejabberd_sm). -spec disco_local_features(disco_acc(), jid(), jid(), binary(), binary()) -> disco_acc(). disco_local_features(Acc, From, To, Node, Lang) -> disco_features(Acc, From, To, Node, Lang, ejabberd_local). -spec disco_sm_features(disco_acc(), jid(), jid(), binary(), binary()) -> disco_acc(). disco_sm_features(Acc, From, To, Node, Lang) -> disco_features(Acc, From, To, Node, Lang, ejabberd_sm). -spec disco_local_identity(disco_acc(), jid(), jid(), binary(), binary()) -> disco_acc(). disco_local_identity(Acc, From, To, Node, Lang) -> disco_identity(Acc, From, To, Node, Lang, ejabberd_local). -spec disco_sm_identity(disco_acc(), jid(), jid(), binary(), binary()) -> disco_acc(). disco_sm_identity(Acc, From, To, Node, Lang) -> disco_identity(Acc, From, To, Node, Lang, ejabberd_sm). %%%=================================================================== %%% gen_server callbacks %%%=================================================================== init([Host, _Opts]) -> process_flag(trap_exit, true), ejabberd_hooks:add(component_connected, ?MODULE, component_connected, 50), ejabberd_hooks:add(component_disconnected, ?MODULE, component_disconnected, 50), ejabberd_hooks:add(disco_local_features, Host, ?MODULE, disco_local_features, 50), ejabberd_hooks:add(disco_sm_features, Host, ?MODULE, disco_sm_features, 50), ejabberd_hooks:add(disco_local_identity, Host, ?MODULE, disco_local_identity, 50), ejabberd_hooks:add(disco_sm_identity, Host, ?MODULE, disco_sm_identity, 50), {ok, #state{server_host = Host}}. handle_call(get_delegations, _From, State) -> {reply, {ok, State#state.delegations}, State}; handle_call(_Request, _From, State) -> Reply = ok, {reply, Reply, State}. handle_cast({component_connected, Host}, State) -> ServerHost = State#state.server_host, To = jid:make(Host), NSAttrsAccessList = gen_mod:get_module_opt( ServerHost, ?MODULE, namespaces), lists:foreach( fun({NS, _Attrs, Access}) -> case acl:match_rule(ServerHost, Access, To) of allow -> send_disco_queries(ServerHost, Host, NS); deny -> ok end end, NSAttrsAccessList), {noreply, State}; handle_cast({component_disconnected, Host}, State) -> ServerHost = State#state.server_host, Delegations = dict:filter( fun({NS, Type}, {H, _}) when H == Host -> ?INFO_MSG("Remove delegation of namespace '~s' " "from external component '~s'", [NS, Host]), gen_iq_handler:remove_iq_handler(Type, ServerHost, NS), false; (_, _) -> true end, State#state.delegations), {noreply, State#state{delegations = Delegations}}; handle_cast(_Msg, State) -> {noreply, State}. handle_info({iq_reply, ResIQ, {disco_info, Type, Host, NS}}, State) -> {noreply, case ResIQ of #iq{type = result, sub_els = [SubEl]} -> try xmpp:decode(SubEl) of #disco_info{} = Info -> process_disco_info(State, Type, Host, NS, Info) catch _:{xmpp_codec, _} -> State end; _ -> State end}; handle_info({iq_reply, ResIQ, #iq{} = IQ}, State) -> process_iq_result(IQ, ResIQ), {noreply, State}; handle_info(Info, State) -> ?WARNING_MSG("unexpected info: ~p", [Info]), {noreply, State}. terminate(_Reason, State) -> %% Note: we don't remove component_* hooks because they are global %% and might be registered within a module on another virtual host ServerHost = State#state.server_host, ejabberd_hooks:delete(disco_local_features, ServerHost, ?MODULE, disco_local_features, 50), ejabberd_hooks:delete(disco_sm_features, ServerHost, ?MODULE, disco_sm_features, 50), ejabberd_hooks:delete(disco_local_identity, ServerHost, ?MODULE, disco_local_identity, 50), ejabberd_hooks:delete(disco_sm_identity, ServerHost, ?MODULE, disco_sm_identity, 50), lists:foreach( fun({NS, Type}) -> gen_iq_handler:remove_iq_handler(Type, ServerHost, NS) end, dict:fetch_keys(State#state.delegations)). code_change(_OldVsn, State, _Extra) -> {ok, State}. %%%=================================================================== %%% Internal functions %%%=================================================================== -spec get_delegations(binary()) -> dict:dict(). get_delegations(Host) -> Proc = gen_mod:get_module_proc(Host, ?MODULE), try gen_server:call(Proc, get_delegations) of {ok, Delegations} -> Delegations catch exit:{noproc, _} -> %% No module is loaded for this virtual host dict:new() end. -spec process_iq(iq(), ejabberd_local | ejabberd_sm) -> ignore | iq(). process_iq(#iq{to = To, lang = Lang, sub_els = [SubEl]} = IQ, Type) -> LServer = To#jid.lserver, NS = xmpp:get_ns(SubEl), Delegations = get_delegations(LServer), case dict:find({NS, Type}, Delegations) of {ok, {Host, _}} -> Delegation = #delegation{ forwarded = #forwarded{sub_els = [IQ]}}, NewFrom = jid:make(LServer), NewTo = jid:make(Host), ejabberd_router:route_iq( #iq{type = set, from = NewFrom, to = NewTo, sub_els = [Delegation]}, IQ, gen_mod:get_module_proc(LServer, ?MODULE)), ignore; error -> Txt = <<"Failed to map delegated namespace to external component">>, xmpp:make_error(IQ, xmpp:err_internal_server_error(Txt, Lang)) end. -spec process_iq_result(iq(), iq()) -> ok. process_iq_result(#iq{from = From, to = To, id = ID, lang = Lang} = IQ, #iq{type = result} = ResIQ) -> try CodecOpts = ejabberd_config:codec_options(To#jid.lserver), #delegation{forwarded = #forwarded{sub_els = [SubEl]}} = xmpp:get_subtag(ResIQ, #delegation{}), case xmpp:decode(SubEl, ?NS_CLIENT, CodecOpts) of #iq{from = To, to = From, type = Type, id = ID} = Reply when Type == error; Type == result -> ejabberd_router:route(Reply) end catch _:_ -> ?ERROR_MSG("got iq-result with invalid delegated " "payload:~n~s", [xmpp:pp(ResIQ)]), Txt = <<"External component failure">>, Err = xmpp:err_internal_server_error(Txt, Lang), ejabberd_router:route_error(IQ, Err) end; process_iq_result(#iq{from = From, to = To}, #iq{type = error} = ResIQ) -> Err = xmpp:set_from_to(ResIQ, To, From), ejabberd_router:route(Err); process_iq_result(#iq{lang = Lang} = IQ, timeout) -> Txt = <<"External component timeout">>, Err = xmpp:err_internal_server_error(Txt, Lang), ejabberd_router:route_error(IQ, Err). -spec process_disco_info(state(), ejabberd_local | ejabberd_sm, binary(), binary(), disco_info()) -> state(). process_disco_info(State, Type, Host, NS, Info) -> From = jid:make(State#state.server_host), To = jid:make(Host), case dict:find({NS, Type}, State#state.delegations) of error -> Msg = #message{from = From, to = To, sub_els = [#delegation{delegated = [#delegated{ns = NS}]}]}, Delegations = dict:store({NS, Type}, {Host, Info}, State#state.delegations), gen_iq_handler:add_iq_handler(Type, State#state.server_host, NS, ?MODULE, Type), ejabberd_router:route(Msg), ?INFO_MSG("Namespace '~s' is delegated to external component '~s'", [NS, Host]), State#state{delegations = Delegations}; {ok, {AnotherHost, _}} -> ?WARNING_MSG("Failed to delegate namespace '~s' to " "external component '~s' because it's already " "delegated to '~s'", [NS, Host, AnotherHost]), State end. -spec send_disco_queries(binary(), binary(), binary()) -> ok. send_disco_queries(LServer, Host, NS) -> From = jid:make(LServer), To = jid:make(Host), lists:foreach( fun({Type, Node}) -> ejabberd_router:route_iq( #iq{type = get, from = From, to = To, sub_els = [#disco_info{node = Node}]}, {disco_info, Type, Host, NS}, gen_mod:get_module_proc(LServer, ?MODULE)) end, [{ejabberd_local, <<(?NS_DELEGATION)/binary, "::", NS/binary>>}, {ejabberd_sm, <<(?NS_DELEGATION)/binary, ":bare:", NS/binary>>}]). -spec disco_features(disco_acc(), jid(), jid(), binary(), binary(), ejabberd_local | ejabberd_sm) -> disco_acc(). disco_features(Acc, _From, To, <<"">>, _Lang, Type) -> Delegations = get_delegations(To#jid.lserver), Features = my_features(Type) ++ lists:flatmap( fun({{_, T}, {_, Info}}) when T == Type -> Info#disco_info.features; (_) -> [] end, dict:to_list(Delegations)), case Acc of empty when Features /= [] -> {result, Features}; {result, Fs} -> {result, Fs ++ Features}; _ -> Acc end; disco_features(Acc, _, _, _, _, _) -> Acc. -spec disco_identity(disco_acc(), jid(), jid(), binary(), binary(), ejabberd_local | ejabberd_sm) -> disco_acc(). disco_identity(Acc, _From, To, <<"">>, _Lang, Type) -> Delegations = get_delegations(To#jid.lserver), Identities = lists:flatmap( fun({{_, T}, {_, Info}}) when T == Type -> Info#disco_info.identities; (_) -> [] end, dict:to_list(Delegations)), case Acc of empty when Identities /= [] -> {result, Identities}; {result, Ids} -> {result, Ids ++ Identities}; Acc -> Acc end; disco_identity(Acc, _From, _To, _Node, _Lang, _Type) -> Acc. my_features(ejabberd_local) -> [?NS_DELEGATION]; my_features(ejabberd_sm) -> [].