diff options
Diffstat (limited to 'src/mod_privilege.erl')
| -rw-r--r-- | src/mod_privilege.erl | 363 |
1 files changed, 363 insertions, 0 deletions
diff --git a/src/mod_privilege.erl b/src/mod_privilege.erl new file mode 100644 index 000000000..af6dacec4 --- /dev/null +++ b/src/mod_privilege.erl @@ -0,0 +1,363 @@ +%%%-------------------------------------------------------------------------------------- +%%% File : mod_privilege.erl +%%% Author : Anna Mukharram <amuhar3@gmail.com> +%%% Purpose : This module is an implementation for XEP-0356: Privileged Entity +%%%-------------------------------------------------------------------------------------- + +-module(mod_privilege). + +-author('amuhar3@gmail.com'). + +-protocol({xep, 0356, '0.2.1'}). + +-export([advertise_permissions/1, initial_presences/1, process_presence/1, + process_roster_presence/1, compare_presences/2, + process_message/4, process_iq/4]). + +-include("ejabberd_service.hrl"). + +-include("mod_privacy.hrl"). + +%%%-------------------------------------------------------------------------------------- +%%% Functions to advertise services of allowed permission +%%%-------------------------------------------------------------------------------------- + +-spec permissions(binary(), binary(), list()) -> xmlel(). + +permissions(From, To, PrivAccess) -> + Perms = lists:map(fun({Access, Type}) -> + ?DEBUG("Advertise service ~s of allowed permission: ~s = ~s~n", + [To, Access, Type]), + #xmlel{name = <<"perm">>, + attrs = [{<<"access">>, + atom_to_binary(Access,latin1)}, + {<<"type">>, Type}]} + end, PrivAccess), + Stanza = #xmlel{name = <<"privilege">>, + attrs = [{<<"xmlns">> ,?NS_PRIVILEGE}], + children = Perms}, + Id = randoms:get_string(), + #xmlel{name = <<"message">>, + attrs = [{<<"id">>, Id}, {<<"from">>, From}, {<<"to">>, To}], + children = [Stanza]}. + +advertise_permissions(#state{privilege_access = []}) -> ok; +advertise_permissions(StateData) -> + Stanza = + permissions(?MYNAME, StateData#state.host, StateData#state.privilege_access), + ejabberd_service:send_element(StateData, Stanza). + +%%%-------------------------------------------------------------------------------------- +%%% Process presences +%%%-------------------------------------------------------------------------------------- + +initial_presences(StateData) -> + Pids = ejabberd_sm:get_all_pids(), + lists:foreach( + fun(Pid) -> + {User, Server, Resource, PresenceLast} = ejabberd_c2s:get_last_presence(Pid), + From = #jid{user = User, server = Server, resource = Resource}, + To = jid:from_string(StateData#state.host), + PacketNew = jlib:replace_from_to(From, To, PresenceLast), + ejabberd_service:send_element(StateData, PacketNew) + end, Pids). + +%% hook user_send_packet(Packet, C2SState, From, To) -> Packet +%% for Managed Entity Presence +process_presence(Pid) -> + fun(#xmlel{name = <<"presence">>} = Packet, _C2SState, From, _To) -> + case fxml:get_attr_s(<<"type">>, Packet#xmlel.attrs) of + T when (T == <<"">>) or (T == <<"unavailable">>) -> + Pid ! {user_presence, Packet, From}; + _ -> ok + end, + Packet; + (Packet, _C2SState, _From, _To) -> + Packet + end. +%% s2s_receive_packet(From, To, Packet) -> ok +%% for Roster Presence +%% From subscription "from" or "both" +process_roster_presence(Pid) -> + fun(From, To, #xmlel{name = <<"presence">>} = Packet) -> + case fxml:get_attr_s(<<"type">>, Packet#xmlel.attrs) of + T when (T == <<"">>) or (T == <<"unavailable">>) -> + Server = To#jid.server, + User = To#jid.user, + PrivList = ejabberd_hooks:run_fold(privacy_get_user_list, + Server, #userlist{}, [User, Server]), + case privacy_check_packet(Server, User, PrivList, From, To, Packet, in) of + allow -> + Pid ! {roster_presence, Packet, From}; + _ -> ok + end, + ok; + _ -> ok + end; + (_From, _To, _Packet) -> ok + end. + +%%%-------------------------------------------------------------------------------------- +%%% Manage Roster +%%%-------------------------------------------------------------------------------------- + +process_iq(StateData, FromJID, ToJID, Packet) -> + IQ = jlib:iq_query_or_response_info(Packet), + case IQ of + #iq{xmlns = ?NS_ROSTER} -> + case (ToJID#jid.luser /= <<"">>) and + (FromJID#jid.luser == <<"">>) and + lists:member(ToJID#jid.lserver, ?MYHOSTS) of + true -> + AccessType = + proplists:get_value(roster, StateData#state.privilege_access, none), + case IQ#iq.type of + get when (AccessType == <<"both">>) or (AccessType == <<"get">>) -> + RosterIQ = roster_management(ToJID, FromJID, IQ), + ejabberd_service:send_element(StateData, RosterIQ); + set when (AccessType == <<"both">>) or (AccessType == <<"set">>) -> + %% check if user ToJID exist + #jid{lserver = Server, luser = User} = ToJID, + case ejabberd_auth:is_user_exists(User,Server) of + true -> + ResIQ = roster_management(ToJID, FromJID, IQ), + ejabberd_service:send_element(StateData, ResIQ); + _ -> ok + end; + _ -> + Err = jlib:make_error_reply(Packet, ?ERR_FORBIDDEN), + ejabberd_service:send_element(StateData, Err) + end; + _ -> + ejabberd_router:route(FromJID, ToJID, Packet) + end; + #iq{type = Type, id = Id} when (Type == error) or (Type == result) -> % for XEP-0355 + Hook = {iq, Type, Id}, + Host = ToJID#jid.lserver, + case (ToJID#jid.luser == <<"">>) and + (FromJID#jid.luser == <<"">>) and + lists:member(ToJID#jid.lserver, ?MYHOSTS) of + true -> + case ets:lookup(hooks_tmp, {Hook, Host}) of + [{_, Function, _Timestamp}] -> + catch apply(Function, [Packet]); + [] -> + ejabberd_router:route(FromJID, ToJID, Packet) + end; + _ -> + ejabberd_router:route(FromJID, ToJID, Packet) + end; + _ -> + ejabberd_router:route(FromJID, ToJID, Packet) + end. + +roster_management(FromJID, ToJID, IQ) -> + ResIQ = mod_roster:process_iq(FromJID, FromJID, IQ), + ResXml = jlib:iq_to_xml(ResIQ), + jlib:replace_from_to(FromJID, ToJID, ResXml). + +%%%-------------------------------------------------------------------------------------- +%%% Message permission +%%%-------------------------------------------------------------------------------------- + +process_message(StateData, FromJID, ToJID, #xmlel{children = Children} = Packet) -> + %% if presence was send from service to server, + case lists:member(ToJID#jid.lserver, ?MYHOSTS) and + (ToJID#jid.luser == <<"">>) and + (FromJID#jid.luser == <<"">>) of %% service + true -> + %% if stanza contains privilege element + case Children of + [#xmlel{name = <<"privilege">>, + attrs = [{<<"xmlns">>, ?NS_PRIVILEGE}], + children = [#xmlel{name = <<"forwarded">>, + attrs = [{<<"xmlns">>, ?NS_FORWARD}], + children = Children2}]}] -> + %% 1 case : privilege service send subscription message + %% on behalf of the client + %% 2 case : privilege service send message on behalf + %% of the client + case Children2 of + %% it isn't case of 0356 extension + [#xmlel{name = <<"presence">>} = Child] -> + forward_subscribe(StateData, Child, Packet); + [#xmlel{name = <<"message">>} = Child] -> %% xep-0356 + forward_message(StateData, Child, Packet); + _ -> + Lang = fxml:get_tag_attr_s(<<"xml:lang">>, Packet), + Txt = <<"invalid forwarded element">>, + Err = jlib:make_error_reply(Packet, ?ERRT_BAD_REQUEST(Lang, Txt)), + ejabberd_service:send_element(StateData, Err) + end; + _ -> + ejabberd_router:route(FromJID, ToJID, Packet) + end; + + _ -> + ejabberd_router:route(FromJID, ToJID, Packet) + end. + +forward_subscribe(StateData, Presence, Packet) -> + PrivAccess = StateData#state.privilege_access, + T = proplists:get_value(roster, PrivAccess, none), + Type = fxml:get_attr_s(<<"type">>, Presence#xmlel.attrs), + if + ((T == <<"both">>) or (T == <<"set">>)) and (Type == <<"subscribe">>) -> + From = fxml:get_attr_s(<<"from">>, Presence#xmlel.attrs), + FromJ = jid:from_string(From), + To = fxml:get_attr_s(<<"to">>, Presence#xmlel.attrs), + ToJ = case To of + <<"">> -> error; + _ -> jid:from_string(To) + end, + if + (ToJ /= error) and (FromJ /= error) -> + Server = FromJ#jid.lserver, + User = FromJ#jid.luser, + case (FromJ#jid.lresource == <<"">>) and + lists:member(Server, ?MYHOSTS) of + true -> + if + (Server /= ToJ#jid.lserver) or + (User /= ToJ#jid.luser) -> + %% 0356 server MUST NOT allow the privileged entity + %% to do anything that the managed entity could not do + try_roster_subscribe(Server,User, FromJ, ToJ, Presence); + true -> %% we don't want presence sent to self + ok + end; + _ -> + Err = jlib:make_error_reply(Packet, ?ERR_FORBIDDEN), + ejabberd_service:send_element(StateData, Err) + end; + true -> + Lang = fxml:get_tag_attr_s(<<"xml:lang">>, Packet), + Txt = <<"Incorrect stanza from/to JID">>, + Err = jlib:make_error_reply(Packet, ?ERRT_BAD_REQUEST(Lang, Txt)), + ejabberd_service:send_element(StateData, Err) + end; + true -> + Err = jlib:make_error_reply(Packet, ?ERR_FORBIDDEN), + ejabberd_service:send_element(StateData, Err) + end. + +forward_message(StateData, Message, Packet) -> + PrivAccess = StateData#state.privilege_access, + T = proplists:get_value(message, PrivAccess, none), + if + (T == <<"outgoing">>) -> + From = fxml:get_attr_s(<<"from">>, Message#xmlel.attrs), + FromJ = jid:from_string(From), + To = fxml:get_attr_s(<<"to">>, Message#xmlel.attrs), + ToJ = case To of + <<"">> -> FromJ; + _ -> jid:from_string(To) + end, + if + (ToJ /= error) and (FromJ /= error) -> + Server = FromJ#jid.server, + User = FromJ#jid.user, + case (FromJ#jid.lresource == <<"">>) and + lists:member(Server, ?MYHOSTS) of + true -> + %% there are no restriction on to attribute + PrivList = ejabberd_hooks:run_fold(privacy_get_user_list, + Server, #userlist{}, + [User, Server]), + check_privacy_route(Server, User, PrivList, + FromJ, ToJ, Message); + _ -> + Err = jlib:make_error_reply(Packet, ?ERR_FORBIDDEN), + ejabberd_service:send_element(StateData, Err) + end; + true -> + Lang = fxml:get_tag_attr_s(<<"xml:lang">>, Packet), + Txt = <<"Incorrect stanza from/to JID">>, + Err = jlib:make_error_reply(Packet, ?ERRT_BAD_REQUEST(Lang, Txt)), + ejabberd_service:send_element(StateData, Err) + end; + true -> + Err = jlib:make_error_reply(Packet,?ERR_FORBIDDEN), + ejabberd_service:send_element(StateData, Err) + end. + +%%%-------------------------------------------------------------------------------------- +%%% helper functions +%%%-------------------------------------------------------------------------------------- + +compare_presences(undefined, _Presence) -> false; +compare_presences(#xmlel{attrs = Attrs, children = Child}, + #xmlel{attrs = Attrs2, children = Child2}) -> + Id1 = fxml:get_attr_s(<<"id">>, Attrs), + Id2 = fxml:get_attr_s(<<"id">>, Attrs2), + if + (Id1 /= Id2) -> + false; + (Id1 /= <<"">>) and (Id1 == Id2) -> + true; + true -> + case not compare_attrs(Attrs, Attrs2) of + true -> false; + _ -> + compare_elements(Child, Child2) + end + end. + + +compare_elements([],[]) -> true; +compare_elements(Tags1, Tags2) when length(Tags1) == length(Tags2) -> + compare_tags(Tags1,Tags2); +compare_elements(_Tags1, _Tags2) -> false. + +compare_tags([],[]) -> true; +compare_tags([{xmlcdata, CData}|Tags1], [{xmlcdata, CData}|Tags2]) -> + compare_tags(Tags1, Tags2); +compare_tags([{xmlcdata, _CData1}|_Tags1], [{xmlcdata, _CData2}|_Tags2]) -> + false; +compare_tags([#xmlel{} = Stanza1|Tags1], [#xmlel{} = Stanza2|Tags2]) -> + case (Stanza1#xmlel.name == Stanza2#xmlel.name) and + compare_attrs(Stanza1#xmlel.attrs, Stanza2#xmlel.attrs) and + compare_tags(Stanza1#xmlel.children, Stanza2#xmlel.children) of + true -> + compare_tags(Tags1,Tags2); + false -> + false + end. + +%% attr() :: {Name, Value} +-spec compare_attrs([attr()], [attr()]) -> boolean(). +compare_attrs([],[]) -> true; +compare_attrs(Attrs1, Attrs2) when length(Attrs1) == length(Attrs2) -> + lists:foldl(fun(Attr,Acc) -> lists:member(Attr, Attrs2) and Acc end, true, Attrs1); +compare_attrs(_Attrs1, _Attrs2) -> false. + +%% Check if privacy rules allow this delivery +%% from ejabberd_c2s.erl +privacy_check_packet(Server, User, PrivList, From, To, Packet , Dir) -> + ejabberd_hooks:run_fold(privacy_check_packet, + Server, allow, [User, Server, PrivList, + {From, To, Packet}, Dir]). + +check_privacy_route(Server, User, PrivList, From, To, Packet) -> + case privacy_check_packet(Server, User, PrivList, From, To, Packet, out) of + allow -> + ejabberd_router:route(From, To, Packet); + _ -> ok %% who should receive error : service or user? + end. + +try_roster_subscribe(Server,User, From, To, Packet) -> + Access = + gen_mod:get_module_opt(Server, mod_roster, access, + fun(A) when is_atom(A) -> A end, all), + case acl:match_rule(Server, Access, From) of + deny -> + ok; + allow -> + ejabberd_hooks:run(roster_out_subscription, Server, + [User, Server, To, subscribe]), + PrivList = ejabberd_hooks:run_fold(privacy_get_user_list, + Server, + #userlist{}, + [User, Server]), + check_privacy_route(Server, User, PrivList, From, To, Packet) + end. |