135 lines
4.6 KiB
Erlang
135 lines
4.6 KiB
Erlang
%%%----------------------------------------------------------------------
|
|
%%% File : mod_pres_counter.erl
|
|
%%% Author : Ahmed Omar
|
|
%%% Purpose : Presence subscription flood prevention
|
|
%%% Created : 23 Sep 2010 by Ahmed Omar
|
|
%%%
|
|
%%%
|
|
%%% ejabberd, Copyright (C) 2002-2012 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
|
|
%%%
|
|
%%%----------------------------------------------------------------------
|
|
|
|
-module(mod_pres_counter).
|
|
|
|
-behavior(gen_mod).
|
|
|
|
-export([start/2,
|
|
stop/1,
|
|
check_packet/6]).
|
|
|
|
-include("ejabberd.hrl").
|
|
-include("jlib.hrl").
|
|
|
|
-record(pres_counter, {dir, start, count, logged = false}).
|
|
|
|
start(Host, Opts) when is_list(Host) ->
|
|
start(list_to_binary(Host), Opts);
|
|
start(HostB, _Opts) ->
|
|
ejabberd_hooks:add(privacy_check_packet, HostB,
|
|
?MODULE, check_packet, 25),
|
|
ok.
|
|
|
|
stop(Host) ->
|
|
HostB = list_to_binary(Host),
|
|
ejabberd_hooks:delete(privacy_check_packet, HostB,
|
|
?MODULE, check_packet, 25),
|
|
ok.
|
|
|
|
check_packet(_, _User, Server,
|
|
_PrivacyList,
|
|
{From, To, Stanza},
|
|
Dir) ->
|
|
case exmpp_presence:is_presence(Stanza) of
|
|
true ->
|
|
IsSubscription =
|
|
case exmpp_presence:get_type(Stanza) of
|
|
subscribe -> true;
|
|
subscribed -> true;
|
|
unsubscribe -> true;
|
|
unsubscribed -> true;
|
|
_ -> false
|
|
end,
|
|
if
|
|
IsSubscription ->
|
|
JID = case Dir of
|
|
in -> To;
|
|
out -> From
|
|
end,
|
|
update(Server, JID, Dir);
|
|
true ->
|
|
allow
|
|
end;
|
|
false ->
|
|
allow
|
|
end.
|
|
|
|
update(Server, JID, Dir) ->
|
|
%% get options
|
|
StormCount = gen_mod:get_module_opt(Server, ?MODULE, count, 5),
|
|
TimeInterval = gen_mod:get_module_opt(Server, ?MODULE, interval, 60),
|
|
{MegaSecs, Secs, _MicroSecs} = now(),
|
|
TimeStamp = MegaSecs * 1000000 + Secs,
|
|
case read(Dir) of
|
|
undefined ->
|
|
write(Dir, #pres_counter{dir = Dir,
|
|
start = TimeStamp,
|
|
count = 1}),
|
|
allow;
|
|
#pres_counter{start = TimeStart, count = Count, logged = Logged} = R ->
|
|
%% record for this key exists, check if we're
|
|
%% within TimeInterval seconds, and whether the StormCount is
|
|
%% high enough. or else just increment the count.
|
|
if
|
|
TimeStamp - TimeStart > TimeInterval ->
|
|
write(Dir, R#pres_counter{
|
|
start = TimeStamp,
|
|
count = 1}),
|
|
allow;
|
|
(Count =:= StormCount) and Logged ->
|
|
{stop, deny};
|
|
Count =:= StormCount ->
|
|
write(Dir, R#pres_counter{logged = true}),
|
|
case Dir of
|
|
in ->
|
|
?WARNING_MSG(
|
|
"User ~s is being flooded, "
|
|
"ignoring received presence subscriptions",
|
|
[exmpp_jid:to_list(JID)]);
|
|
out ->
|
|
{IP, _Port} = ejabberd_sm:get_user_ip(JID),
|
|
?WARNING_MSG(
|
|
"Flooder detected: ~s, on IP: ~s "
|
|
"ignoring sent presence subscriptions",
|
|
[exmpp_jid:to_list(JID),
|
|
inet_parse:ntoa(IP)])
|
|
end,
|
|
{stop, deny};
|
|
true ->
|
|
write(Dir, R#pres_counter{
|
|
start = TimeStamp,
|
|
count = Count + 1}),
|
|
allow
|
|
end
|
|
end.
|
|
|
|
read(K)->
|
|
get({pres_counter, K}).
|
|
|
|
write(K, V)->
|
|
put({pres_counter, K}, V).
|