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mirror of https://github.com/processone/ejabberd.git synced 2024-12-20 17:27:00 +01:00
xmpp.chapril.org-ejabberd/src/mod_caps.erl
2013-06-20 18:40:44 +10:00

589 lines
18 KiB
Erlang

%%%----------------------------------------------------------------------
%%% File : mod_caps.erl
%%% Author : Magnus Henoch <henoch@dtek.chalmers.se>
%%% Purpose : Request and cache Entity Capabilities (XEP-0115)
%%% Created : 7 Oct 2006 by Magnus Henoch <henoch@dtek.chalmers.se>
%%%
%%%
%%% 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
%%%
%%% 2009, improvements from ProcessOne to support correct PEP handling
%%% through s2s, use less memory, and speedup global caps handling
%%%----------------------------------------------------------------------
-module(mod_caps).
-author('henoch@dtek.chalmers.se').
-behaviour(gen_server).
-behaviour(gen_mod).
-export([read_caps/1, caps_stream_features/2,
disco_features/5, disco_identity/5, disco_info/5,
get_features/1]).
%% gen_mod callbacks
-export([start/2, start_link/2, stop/1]).
%% gen_server callbacks
-export([init/1, handle_info/2, handle_call/3,
handle_cast/2, terminate/2, code_change/3]).
%% hook handlers
-export([user_send_packet/3,
user_receive_packet/4,
c2s_presence_in/2,
c2s_broadcast_recipients/5]).
-include("ejabberd.hrl").
-include("logger.hrl").
-include("jlib.hrl").
-define(PROCNAME, ejabberd_mod_caps).
-define(BAD_HASH_LIFETIME, 600).
-record(caps,
{
node = <<"">> :: binary(),
version = <<"">> :: binary(),
hash = <<"">> :: binary(),
exts = [] :: [binary()]
}).
-type caps() :: #caps{}.
-export_type([caps/0]).
-record(caps_features,
{
node_pair = {<<"">>, <<"">>} :: {binary(), binary()},
features = [] :: [binary()] | pos_integer()
}).
-record(state, {host = <<"">> :: binary()}).
%%====================================================================
%% API
%%====================================================================
start_link(Host, Opts) ->
Proc = gen_mod:get_module_proc(Host, ?PROCNAME),
gen_server:start_link({local, Proc}, ?MODULE,
[Host, Opts], []).
start(Host, Opts) ->
Proc = gen_mod:get_module_proc(Host, ?PROCNAME),
ChildSpec = {Proc, {?MODULE, start_link, [Host, Opts]},
transient, 1000, worker, [?MODULE]},
supervisor:start_child(ejabberd_sup, ChildSpec).
stop(Host) ->
Proc = gen_mod:get_module_proc(Host, ?PROCNAME),
gen_server:call(Proc, stop),
supervisor:terminate_child(ejabberd_sup, Proc),
supervisor:delete_child(ejabberd_sup, Proc).
%% get_features returns a list of features implied by the given caps
%% record (as extracted by read_caps) or 'unknown' if features are
%% not completely collected at the moment.
get_features(nothing) -> [];
get_features(#caps{node = Node, version = Version, exts = Exts}) ->
SubNodes = [Version | Exts],
%% read_caps takes a list of XML elements (the child elements of a
%% <presence/> stanza) and returns an opaque value representing the
%% Entity Capabilities contained therein, or the atom nothing if no
%% capabilities are advertised.
lists:foldl(fun (SubNode, Acc) ->
NodePair = {Node, SubNode},
case cache_tab:lookup(caps_features, NodePair,
caps_read_fun(NodePair))
of
{ok, Features} when is_list(Features) ->
Features ++ Acc;
_ -> Acc
end
end,
[], SubNodes).
read_caps(Els) -> read_caps(Els, nothing).
read_caps([#xmlel{name = <<"c">>, attrs = Attrs}
| Tail],
Result) ->
case xml:get_attr_s(<<"xmlns">>, Attrs) of
?NS_CAPS ->
Node = xml:get_attr_s(<<"node">>, Attrs),
Version = xml:get_attr_s(<<"ver">>, Attrs),
Hash = xml:get_attr_s(<<"hash">>, Attrs),
Exts = str:tokens(xml:get_attr_s(<<"ext">>, Attrs),
<<" ">>),
read_caps(Tail,
#caps{node = Node, hash = Hash, version = Version,
exts = Exts});
_ -> read_caps(Tail, Result)
end;
read_caps([#xmlel{name = <<"x">>, attrs = Attrs}
| Tail],
Result) ->
case xml:get_attr_s(<<"xmlns">>, Attrs) of
?NS_MUC_USER -> nothing;
_ -> read_caps(Tail, Result)
end;
read_caps([_ | Tail], Result) ->
read_caps(Tail, Result);
read_caps([], Result) -> Result.
%%====================================================================
%% Hooks
%%====================================================================
user_send_packet(
#jid{luser = User, lserver = Server} = From,
#jid{luser = User, lserver = Server, lresource = <<"">>},
#xmlel{name = <<"presence">>, attrs = Attrs, children = Els}) ->
Type = xml:get_attr_s(<<"type">>, Attrs),
if Type == <<"">>; Type == <<"available">> ->
case read_caps(Els) of
nothing -> ok;
#caps{version = Version, exts = Exts} = Caps ->
feature_request(Server, From, Caps, [Version | Exts])
end;
true -> ok
end;
user_send_packet(_From, _To, _Packet) -> ok.
user_receive_packet(#jid{lserver = Server}, From, _To,
#xmlel{name = <<"presence">>, attrs = Attrs,
children = Els}) ->
Type = xml:get_attr_s(<<"type">>, Attrs),
IsRemote = not lists:member(From#jid.lserver, ?MYHOSTS),
if IsRemote and
((Type == <<"">>) or (Type == <<"available">>)) ->
case read_caps(Els) of
nothing -> ok;
#caps{version = Version, exts = Exts} = Caps ->
feature_request(Server, From, Caps, [Version | Exts])
end;
true -> ok
end;
user_receive_packet(_JID, _From, _To, _Packet) ->
ok.
caps_stream_features(Acc, MyHost) ->
case make_my_disco_hash(MyHost) of
<<"">> -> Acc;
Hash ->
[#xmlel{name = <<"c">>,
attrs =
[{<<"xmlns">>, ?NS_CAPS}, {<<"hash">>, <<"sha-1">>},
{<<"node">>, ?EJABBERD_URI}, {<<"ver">>, Hash}],
children = []}
| Acc]
end.
disco_features(Acc, From, To, Node, Lang) ->
case is_valid_node(Node) of
true ->
ejabberd_hooks:run_fold(disco_local_features,
To#jid.lserver, empty,
[From, To, <<"">>, Lang]);
false ->
Acc
end.
disco_identity(Acc, From, To, Node, Lang) ->
case is_valid_node(Node) of
true ->
ejabberd_hooks:run_fold(disco_local_identity,
To#jid.lserver, [],
[From, To, <<"">>, Lang]);
false ->
Acc
end.
disco_info(Acc, Host, Module, Node, Lang) ->
case is_valid_node(Node) of
true ->
ejabberd_hooks:run_fold(disco_info, Host, [],
[Host, Module, <<"">>, Lang]);
false ->
Acc
end.
c2s_presence_in(C2SState,
{From, To, {_, _, Attrs, Els}}) ->
Type = xml:get_attr_s(<<"type">>, Attrs),
Subscription = ejabberd_c2s:get_subscription(From,
C2SState),
Insert = ((Type == <<"">>) or (Type == <<"available">>))
and ((Subscription == both) or (Subscription == to)),
Delete = (Type == <<"unavailable">>) or
(Type == <<"error">>),
if Insert or Delete ->
LFrom = jlib:jid_tolower(From),
Rs = case ejabberd_c2s:get_aux_field(caps_resources,
C2SState)
of
{ok, Rs1} -> Rs1;
error -> gb_trees:empty()
end,
Caps = read_caps(Els),
{CapsUpdated, NewRs} = case Caps of
nothing when Insert == true -> {false, Rs};
_ when Insert == true ->
case gb_trees:lookup(LFrom, Rs) of
{value, Caps} -> {false, Rs};
none ->
{true,
gb_trees:insert(LFrom, Caps,
Rs)};
_ ->
{true,
gb_trees:update(LFrom, Caps, Rs)}
end;
_ -> {false, gb_trees:delete_any(LFrom, Rs)}
end,
if CapsUpdated ->
ejabberd_hooks:run(caps_update, To#jid.lserver,
[From, To, get_features(Caps)]);
true -> ok
end,
ejabberd_c2s:set_aux_field(caps_resources, NewRs,
C2SState);
true -> C2SState
end.
c2s_broadcast_recipients(InAcc, C2SState, {pep_message, Feature},
_From, _Packet) ->
case ejabberd_c2s:get_aux_field(caps_resources, C2SState) of
{ok, Rs} ->
gb_trees_fold(
fun(USR, Caps, Acc) ->
case lists:member(Feature, get_features(Caps)) of
true ->
[USR|Acc];
false ->
Acc
end
end, InAcc, Rs);
_ ->
InAcc
end;
c2s_broadcast_recipients(Acc, _, _, _, _) ->
Acc.
%%====================================================================
%% gen_server callbacks
%%====================================================================
init([Host, Opts]) ->
case catch mnesia:table_info(caps_features, storage_type) of
{'EXIT', _} ->
ok;
disc_only_copies ->
ok;
_ ->
mnesia:delete_table(caps_features)
end,
mnesia:create_table(caps_features,
[{disc_only_copies, [node()]},
{local_content, true},
{attributes, record_info(fields, caps_features)}]),
mnesia:add_table_copy(caps_features, node(), disc_only_copies),
MaxSize = gen_mod:get_opt(cache_size, Opts, fun(CS) when is_integer(CS) -> CS end, 1000),
LifeTime = gen_mod:get_opt(cache_life_time, Opts, fun(CL) when is_integer(CL) -> CL end, timer:hours(24) div 1000),
cache_tab:new(caps_features, [{max_size, MaxSize}, {life_time, LifeTime}]),
ejabberd_hooks:add(c2s_presence_in, Host,
?MODULE, c2s_presence_in, 75),
ejabberd_hooks:add(c2s_broadcast_recipients, Host,
?MODULE, c2s_broadcast_recipients, 75),
ejabberd_hooks:add(user_send_packet, Host,
?MODULE, user_send_packet, 75),
ejabberd_hooks:add(user_receive_packet, Host,
?MODULE, user_receive_packet, 75),
ejabberd_hooks:add(c2s_stream_features, Host,
?MODULE, caps_stream_features, 75),
ejabberd_hooks:add(s2s_stream_features, Host,
?MODULE, caps_stream_features, 75),
ejabberd_hooks:add(disco_local_features, Host,
?MODULE, disco_features, 75),
ejabberd_hooks:add(disco_local_identity, Host,
?MODULE, disco_identity, 75),
ejabberd_hooks:add(disco_info, Host,
?MODULE, disco_info, 75),
{ok, #state{host = Host}}.
handle_call(stop, _From, State) ->
{stop, normal, ok, State};
handle_call(_Req, _From, State) ->
{reply, {error, badarg}, State}.
handle_cast(_Msg, State) -> {noreply, State}.
handle_info(_Info, State) -> {noreply, State}.
terminate(_Reason, State) ->
Host = State#state.host,
ejabberd_hooks:delete(c2s_presence_in, Host, ?MODULE,
c2s_presence_in, 75),
ejabberd_hooks:delete(c2s_broadcast_recipients, Host,
?MODULE, c2s_broadcast_recipients, 75),
ejabberd_hooks:delete(user_send_packet, Host, ?MODULE,
user_send_packet, 75),
ejabberd_hooks:delete(user_receive_packet, Host,
?MODULE, user_receive_packet, 75),
ejabberd_hooks:delete(c2s_stream_features, Host,
?MODULE, caps_stream_features, 75),
ejabberd_hooks:delete(s2s_stream_features, Host,
?MODULE, caps_stream_features, 75),
ejabberd_hooks:delete(disco_local_features, Host,
?MODULE, disco_features, 75),
ejabberd_hooks:delete(disco_local_identity, Host,
?MODULE, disco_identity, 75),
ejabberd_hooks:delete(disco_info, Host, ?MODULE,
disco_info, 75),
ok.
code_change(_OldVsn, State, _Extra) -> {ok, State}.
%%====================================================================
%% Aux functions
%%====================================================================
feature_request(Host, From, Caps,
[SubNode | Tail] = SubNodes) ->
Node = Caps#caps.node,
NodePair = {Node, SubNode},
case cache_tab:lookup(caps_features, NodePair,
caps_read_fun(NodePair))
of
{ok, Fs} when is_list(Fs) ->
feature_request(Host, From, Caps, Tail);
Other ->
NeedRequest = case Other of
{ok, TS} -> now_ts() >= TS + (?BAD_HASH_LIFETIME);
_ -> true
end,
if NeedRequest ->
IQ = #iq{type = get, xmlns = ?NS_DISCO_INFO,
sub_el =
[#xmlel{name = <<"query">>,
attrs =
[{<<"xmlns">>, ?NS_DISCO_INFO},
{<<"node">>,
<<Node/binary, "#",
SubNode/binary>>}],
children = []}]},
cache_tab:insert(caps_features, NodePair, now_ts(),
caps_write_fun(NodePair, now_ts())),
F = fun (IQReply) ->
feature_response(IQReply, Host, From, Caps,
SubNodes)
end,
ejabberd_local:route_iq(jlib:make_jid(<<"">>, Host,
<<"">>),
From, IQ, F);
true -> feature_request(Host, From, Caps, Tail)
end
end;
feature_request(_Host, _From, _Caps, []) -> ok.
feature_response(#iq{type = result,
sub_el = [#xmlel{children = Els}]},
Host, From, Caps, [SubNode | SubNodes]) ->
NodePair = {Caps#caps.node, SubNode},
case check_hash(Caps, Els) of
true ->
Features = lists:flatmap(fun (#xmlel{name =
<<"feature">>,
attrs = FAttrs}) ->
[xml:get_attr_s(<<"var">>, FAttrs)];
(_) -> []
end,
Els),
cache_tab:insert(caps_features, NodePair,
Features,
caps_write_fun(NodePair, Features));
false -> ok
end,
feature_request(Host, From, Caps, SubNodes);
feature_response(_IQResult, Host, From, Caps,
[_SubNode | SubNodes]) ->
feature_request(Host, From, Caps, SubNodes).
caps_read_fun(Node) ->
fun () ->
case mnesia:dirty_read({caps_features, Node}) of
[#caps_features{features = Features}] -> {ok, Features};
_ -> error
end
end.
caps_write_fun(Node, Features) ->
fun () ->
mnesia:dirty_write(#caps_features{node_pair = Node,
features = Features})
end.
make_my_disco_hash(Host) ->
JID = jlib:make_jid(<<"">>, Host, <<"">>),
case {ejabberd_hooks:run_fold(disco_local_features,
Host, empty, [JID, JID, <<"">>, <<"">>]),
ejabberd_hooks:run_fold(disco_local_identity, Host, [],
[JID, JID, <<"">>, <<"">>]),
ejabberd_hooks:run_fold(disco_info, Host, [],
[Host, undefined, <<"">>, <<"">>])}
of
{{result, Features}, Identities, Info} ->
Feats = lists:map(fun ({{Feat, _Host}}) ->
#xmlel{name = <<"feature">>,
attrs = [{<<"var">>, Feat}],
children = []};
(Feat) ->
#xmlel{name = <<"feature">>,
attrs = [{<<"var">>, Feat}],
children = []}
end,
Features),
make_disco_hash(Identities ++ Info ++ Feats, sha1);
_Err -> <<"">>
end.
make_disco_hash(DiscoEls, Algo) ->
Concat = list_to_binary([concat_identities(DiscoEls),
concat_features(DiscoEls), concat_info(DiscoEls)]),
jlib:encode_base64(case Algo of
md5 -> crypto:md5(Concat);
sha1 -> crypto:sha(Concat);
sha224 -> p1_sha:sha224(Concat);
sha256 -> p1_sha:sha256(Concat);
sha384 -> p1_sha:sha384(Concat);
sha512 -> p1_sha:sha512(Concat)
end).
check_hash(Caps, Els) ->
case Caps#caps.hash of
<<"md5">> ->
Caps#caps.version == make_disco_hash(Els, md5);
<<"sha-1">> ->
Caps#caps.version == make_disco_hash(Els, sha1);
<<"sha-224">> ->
Caps#caps.version == make_disco_hash(Els, sha224);
<<"sha-256">> ->
Caps#caps.version == make_disco_hash(Els, sha256);
<<"sha-384">> ->
Caps#caps.version == make_disco_hash(Els, sha384);
<<"sha-512">> ->
Caps#caps.version == make_disco_hash(Els, sha512);
_ -> true
end.
concat_features(Els) ->
lists:usort(lists:flatmap(fun (#xmlel{name =
<<"feature">>,
attrs = Attrs}) ->
[[xml:get_attr_s(<<"var">>, Attrs), $<]];
(_) -> []
end,
Els)).
concat_identities(Els) ->
lists:sort(lists:flatmap(fun (#xmlel{name =
<<"identity">>,
attrs = Attrs}) ->
[[xml:get_attr_s(<<"category">>, Attrs),
$/, xml:get_attr_s(<<"type">>, Attrs),
$/,
xml:get_attr_s(<<"xml:lang">>, Attrs),
$/, xml:get_attr_s(<<"name">>, Attrs),
$<]];
(_) -> []
end,
Els)).
concat_info(Els) ->
lists:sort(lists:flatmap(fun (#xmlel{name = <<"x">>,
attrs = Attrs, children = Fields}) ->
case {xml:get_attr_s(<<"xmlns">>, Attrs),
xml:get_attr_s(<<"type">>, Attrs)}
of
{?NS_XDATA, <<"result">>} ->
[concat_xdata_fields(Fields)];
_ -> []
end;
(_) -> []
end,
Els)).
concat_xdata_fields(Fields) ->
[Form, Res] = lists:foldl(fun (#xmlel{name =
<<"field">>,
attrs = Attrs, children = Els} =
El,
[FormType, VarFields] = Acc) ->
case xml:get_attr_s(<<"var">>, Attrs) of
<<"">> -> Acc;
<<"FORM_TYPE">> ->
[xml:get_subtag_cdata(El,
<<"value">>),
VarFields];
Var ->
[FormType,
[[[Var, $<],
lists:sort(lists:flatmap(fun
(#xmlel{name
=
<<"value">>,
children
=
VEls}) ->
[[xml:get_cdata(VEls),
$<]];
(_) ->
[]
end,
Els))]
| VarFields]]
end;
(_, Acc) -> Acc
end,
[<<"">>, []], Fields),
[Form, $<, lists:sort(Res)].
gb_trees_fold(F, Acc, Tree) ->
Iter = gb_trees:iterator(Tree),
gb_trees_fold_iter(F, Acc, Iter).
gb_trees_fold_iter(F, Acc, Iter) ->
case gb_trees:next(Iter) of
{Key, Val, NewIter} ->
NewAcc = F(Key, Val, Acc),
gb_trees_fold_iter(F, NewAcc, NewIter);
_ -> Acc
end.
now_ts() ->
{MegaSecs, Secs, _} = now(), MegaSecs * 1000000 + Secs.
is_valid_node(Node) ->
case str:tokens(Node, <<"#">>) of
[?EJABBERD_URI|_] ->
true;
_ ->
false
end.