%%%---------------------------------------------------------------------- %%% File : mod_carboncopy.erl %%% Author : Eric Cestari %%% Purpose : Message Carbons XEP-0280 0.8 %%% Created : 5 May 2008 by Mickael Remond %%% Usage : Add the following line in modules section of ejabberd.yml: %%% {mod_carboncopy, []} %%% %%% %%% ejabberd, Copyright (C) 2002-2016 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_carboncopy). -author ('ecestari@process-one.net'). -protocol({xep, 280, '0.8'}). -behavior(gen_mod). %% API: -export([start/2, stop/1]). -export([user_send_packet/4, user_receive_packet/5, iq_handler/1, remove_connection/4, is_carbon_copy/1, mod_opt_type/1, depends/2]). -include("ejabberd.hrl"). -include("logger.hrl"). -include("xmpp.hrl"). -define(PROCNAME, ?MODULE). -type direction() :: sent | received. -callback init(binary(), gen_mod:opts()) -> any(). -callback enable(binary(), binary(), binary(), binary()) -> ok | {error, any()}. -callback disable(binary(), binary(), binary()) -> ok | {error, any()}. -callback list(binary(), binary()) -> [{binary(), binary()}]. -spec is_carbon_copy(stanza()) -> boolean(). is_carbon_copy(Packet) -> xmpp:has_subtag(Packet, #carbons_sent{}) orelse xmpp:has_subtag(Packet, #carbons_received{}). start(Host, Opts) -> IQDisc = gen_mod:get_opt(iqdisc, Opts,fun gen_iq_handler:check_type/1, one_queue), mod_disco:register_feature(Host, ?NS_CARBONS_2), Mod = gen_mod:db_mod(Host, ?MODULE), Mod:init(Host, Opts), ejabberd_hooks:add(unset_presence_hook,Host, ?MODULE, remove_connection, 10), %% why priority 89: to define clearly that we must run BEFORE mod_logdb hook (90) ejabberd_hooks:add(user_send_packet,Host, ?MODULE, user_send_packet, 89), ejabberd_hooks:add(user_receive_packet,Host, ?MODULE, user_receive_packet, 89), gen_iq_handler:add_iq_handler(ejabberd_sm, Host, ?NS_CARBONS_2, ?MODULE, iq_handler, IQDisc). stop(Host) -> gen_iq_handler:remove_iq_handler(ejabberd_sm, Host, ?NS_CARBONS_2), mod_disco:unregister_feature(Host, ?NS_CARBONS_2), %% why priority 89: to define clearly that we must run BEFORE mod_logdb hook (90) ejabberd_hooks:delete(user_send_packet,Host, ?MODULE, user_send_packet, 89), ejabberd_hooks:delete(user_receive_packet,Host, ?MODULE, user_receive_packet, 89), ejabberd_hooks:delete(unset_presence_hook,Host, ?MODULE, remove_connection, 10). -spec iq_handler(iq()) -> iq(). iq_handler(#iq{type = set, lang = Lang, from = From, sub_els = [El]} = IQ) when is_record(El, carbons_enable); is_record(El, carbons_disable) -> {U, S, R} = jid:tolower(From), Result = case El of #carbons_enable{} -> ?INFO_MSG("carbons enabled for user ~s@~s/~s", [U,S,R]), enable(S, U, R, ?NS_CARBONS_2); #carbons_disable{} -> ?INFO_MSG("carbons disabled for user ~s@~s/~s", [U,S,R]), disable(S, U, R) end, case Result of ok -> ?DEBUG("carbons IQ result: ok", []), xmpp:make_iq_result(IQ); {error,_Error} -> ?ERROR_MSG("Error enabling / disabling carbons: ~p", [Result]), Txt = <<"Database failure">>, xmpp:make_error(IQ, xmpp:err_internal_server_error(Txt, Lang)) end; iq_handler(#iq{type = set, lang = Lang} = IQ) -> Txt = <<"Only or tags are allowed">>, xmpp:make_error(IQ, xmpp:err_bad_request(Txt, Lang)); iq_handler(#iq{type = get, lang = Lang} = IQ)-> Txt = <<"Value 'get' of 'type' attribute is not allowed">>, xmpp:make_error(IQ, xmpp:err_not_allowed(Txt, Lang)). -spec user_send_packet(stanza(), ejabberd_c2s:state(), jid(), jid()) -> stanza() | {stop, stanza()}. user_send_packet(Packet, _C2SState, From, To) -> check_and_forward(From, To, Packet, sent). -spec user_receive_packet(stanza(), ejabberd_c2s:state(), jid(), jid(), jid()) -> stanza() | {stop, stanza()}. user_receive_packet(Packet, _C2SState, JID, _From, To) -> check_and_forward(JID, To, Packet, received). % Modified from original version: % - registered to the user_send_packet hook, to be called only once even for multicast % - do not support "private" message mode, and do not modify the original packet in any way % - we also replicate "read" notifications -spec check_and_forward(jid(), jid(), stanza(), direction()) -> stanza() | {stop, stanza()}. check_and_forward(JID, To, Packet, Direction)-> case is_chat_message(Packet) andalso not is_muc_pm(To, Packet) andalso xmpp:has_subtag(Packet, #carbons_private{}) == false andalso xmpp:has_subtag(Packet, #hint{type = 'no-copy'}) == false of true -> case is_carbon_copy(Packet) of false -> send_copies(JID, To, Packet, Direction), Packet; true -> %% stop the hook chain, we don't want logging modules to duplicates %% this message {stop, Packet} end; _ -> Packet end. -spec remove_connection(binary(), binary(), binary(), binary()) -> ok. remove_connection(User, Server, Resource, _Status)-> disable(Server, User, Resource), ok. %%% Internal %% Direction = received | sent -spec send_copies(jid(), jid(), message(), direction()) -> ok. send_copies(JID, To, Packet, Direction)-> {U, S, R} = jid:tolower(JID), PrioRes = ejabberd_sm:get_user_present_resources(U, S), {_, AvailRs} = lists:unzip(PrioRes), {MaxPrio, MaxRes} = case catch lists:max(PrioRes) of {Prio, Res} -> {Prio, Res}; _ -> {0, undefined} end, %% unavailable resources are handled like bare JIDs IsBareTo = case {Direction, To} of {received, #jid{lresource = <<>>}} -> true; {received, #jid{lresource = LRes}} -> not lists:member(LRes, AvailRs); _ -> false end, %% list of JIDs that should receive a carbon copy of this message (excluding the %% receiver(s) of the original message TargetJIDs = case {IsBareTo, R} of {true, MaxRes} -> OrigTo = fun(Res) -> lists:member({MaxPrio, Res}, PrioRes) end, [ {jid:make({U, S, CCRes}), CC_Version} || {CCRes, CC_Version} <- list(U, S), lists:member(CCRes, AvailRs), not OrigTo(CCRes) ]; {true, _} -> %% The message was sent to our bare JID, and we currently have %% multiple resources with the same highest priority, so the session %% manager routes the message to each of them. We create carbon %% copies only from one of those resources (the one where R equals %% MaxRes) in order to avoid duplicates. []; {false, _} -> [ {jid:make({U, S, CCRes}), CC_Version} || {CCRes, CC_Version} <- list(U, S), lists:member(CCRes, AvailRs), CCRes /= R ] %TargetJIDs = lists:delete(JID, [ jid:make({U, S, CCRes}) || CCRes <- list(U, S) ]), end, lists:map(fun({Dest, _Version}) -> {_, _, Resource} = jid:tolower(Dest), ?DEBUG("Sending: ~p =/= ~p", [R, Resource]), Sender = jid:make({U, S, <<>>}), %{xmlelement, N, A, C} = Packet, New = build_forward_packet(JID, Packet, Sender, Dest, Direction), ejabberd_router:route(Sender, Dest, New) end, TargetJIDs), ok. -spec build_forward_packet(jid(), message(), jid(), jid(), direction()) -> message(). build_forward_packet(JID, #message{type = T} = Msg, Sender, Dest, Direction) -> Forwarded = #forwarded{xml_els = [xmpp:encode(complete_packet(JID, Msg, Direction))]}, Carbon = case Direction of sent -> #carbons_sent{forwarded = Forwarded}; received -> #carbons_received{forwarded = Forwarded} end, #message{from = Sender, to = Dest, type = T, sub_els = [Carbon]}. -spec enable(binary(), binary(), binary(), binary()) -> ok | {error, any()}. enable(Host, U, R, CC)-> ?DEBUG("enabling for ~p", [U]), Mod = gen_mod:db_mod(Host, ?MODULE), Mod:enable(U, Host, R, CC). -spec disable(binary(), binary(), binary()) -> ok | {error, any()}. disable(Host, U, R)-> ?DEBUG("disabling for ~p", [U]), Mod = gen_mod:db_mod(Host, ?MODULE), Mod:disable(U, Host, R). -spec complete_packet(jid(), message(), direction()) -> message(). complete_packet(From, #message{from = undefined} = Msg, sent) -> %% if this is a packet sent by user on this host, then Packet doesn't %% include the 'from' attribute. We must add it. Msg#message{from = From}; complete_packet(_From, Msg, _Direction) -> Msg. -spec is_chat_message(stanza()) -> boolean(). is_chat_message(#message{type = chat}) -> true; is_chat_message(#message{type = normal, body = [_|_]}) -> true; is_chat_message(_) -> false. is_muc_pm(#jid{lresource = <<>>}, _Packet) -> false; is_muc_pm(_To, Packet) -> xmpp:has_subtag(Packet, #muc_user{}). -spec list(binary(), binary()) -> [{binary(), binary()}]. %% list {resource, cc_version} with carbons enabled for given user and host list(User, Server) -> Mod = gen_mod:db_mod(Server, ?MODULE), Mod:list(User, Server). depends(_Host, _Opts) -> []. mod_opt_type(iqdisc) -> fun gen_iq_handler:check_type/1; mod_opt_type(db_type) -> fun(T) -> ejabberd_config:v_db(?MODULE, T) end; mod_opt_type(_) -> [db_type, iqdisc].