%%%----------------------------------------------------------------------
%%% File : ejabberd_http_poll.erl
%%% Author : Alexey Shchepin <alexey@process-one.net>
%%% Purpose : HTTP Polling support (XEP-0025)
%%% Created : 4 Mar 2004 by Alexey Shchepin <alexey@process-one.net>
%%%
%%%
%%% 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
%%%
%%%----------------------------------------------------------------------
-module(ejabberd_http_poll).
-author('alexey@process-one.net').
-behaviour(gen_fsm).
%% External exports
-export([start_link/3, init/1, handle_event/3,
handle_sync_event/4, code_change/4, handle_info/3,
terminate/3, send/2, setopts/2, sockname/1, peername/1,
controlling_process/2, close/1, process/2]).
-include("ejabberd.hrl").
-include("logger.hrl").
-include("jlib.hrl").
-include("ejabberd_http.hrl").
-record(http_poll, {id :: pid() | binary(), pid :: pid()}).
-type poll_socket() :: #http_poll{}.
-export_type([poll_socket/0]).
-record(state,
{id, key, socket, output = [], input = <<"">>,
waiting_input = false, last_receiver, http_poll_timeout,
timer}).
%-define(DBGFSM, true).
-ifdef(DBGFSM).
-define(FSMOPTS, [{debug, [trace]}]).
-else.
-define(FSMOPTS, []).
-endif.
-define(HTTP_POLL_TIMEOUT, 300).
-define(CT,
{<<"Content-Type">>, <<"text/xml; charset=utf-8">>}).
-define(BAD_REQUEST,
[?CT, {<<"Set-Cookie">>, <<"ID=-3:0; expires=-1">>}]).
%%%----------------------------------------------------------------------
%%% API
%%%----------------------------------------------------------------------
start(ID, Key, IP) ->
mnesia:create_table(http_poll,
[{ram_copies, [node()]},
{attributes, record_info(fields, http_poll)}]),
supervisor:start_child(ejabberd_http_poll_sup, [ID, Key, IP]).
start_link(ID, Key, IP) ->
gen_fsm:start_link(?MODULE, [ID, Key, IP], ?FSMOPTS).
send({http_poll, FsmRef, _IP}, Packet) ->
gen_fsm:sync_send_all_state_event(FsmRef,
{send, Packet}).
setopts({http_poll, FsmRef, _IP}, Opts) ->
case lists:member({active, once}, Opts) of
true ->
gen_fsm:send_all_state_event(FsmRef,
{activate, self()});
_ -> ok
end.
sockname(_Socket) -> {ok, {{0, 0, 0, 0}, 0}}.
peername({http_poll, _FsmRef, IP}) -> {ok, IP}.
controlling_process(_Socket, _Pid) -> ok.
close({http_poll, FsmRef, _IP}) ->
catch gen_fsm:sync_send_all_state_event(FsmRef, close).
process([],
#request{data = Data, ip = IP} = _Request) ->
case catch parse_request(Data) of
{ok, ID1, Key, NewKey, Packet} ->
ID = if
(ID1 == <<"0">>) or (ID1 == <<"mobile">>) ->
NewID = p1_sha:sha(term_to_binary({now(), make_ref()})),
{ok, Pid} = start(NewID, <<"">>, IP),
mnesia:transaction(
fun() ->
mnesia:write(#http_poll{id = NewID, pid = Pid})
end),
NewID;
true ->
ID1
end,
case http_put(ID, Key, NewKey, Packet) of
{error, not_exists} ->
{200, ?BAD_REQUEST, <<"">>};
{error, bad_key} ->
{200, ?BAD_REQUEST, <<"">>};
ok ->
receive
after 100 -> ok
end,
case http_get(ID) of
{error, not_exists} ->
{200, ?BAD_REQUEST, <<"">>};
{ok, OutPacket} ->
if
ID == ID1 ->
Cookie = <<"ID=", ID/binary, "; expires=-1">>,
{200, [?CT, {<<"Set-Cookie">>, Cookie}],
OutPacket};
ID1 == <<"mobile">> ->
{200, [?CT], [ID, $\n, OutPacket]};
true ->
Cookie = <<"ID=", ID/binary, "; expires=-1">>,
{200, [?CT, {<<"Set-Cookie">>, Cookie}],
OutPacket}
end
end
end;
_ ->
HumanHTMLxmlel = get_human_html_xmlel(),
{200, [?CT, {<<"Set-Cookie">>, <<"ID=-2:0; expires=-1">>}], HumanHTMLxmlel}
end;
process(_, _Request) ->
{400, [],
#xmlel{name = <<"h1">>, attrs = [],
children = [{xmlcdata, <<"400 Bad Request">>}]}}.
%% Code copied from mod_http_bind.erl and customized
get_human_html_xmlel() ->
Heading = <<"ejabberd ",
(iolist_to_binary(atom_to_list(?MODULE)))/binary>>,
#xmlel{name = <<"html">>,
attrs =
[{<<"xmlns">>, <<"http://www.w3.org/1999/xhtml">>}],
children =
[#xmlel{name = <<"head">>, attrs = [],
children =
[#xmlel{name = <<"title">>, attrs = [],
children = [{xmlcdata, Heading}]}]},
#xmlel{name = <<"body">>, attrs = [],
children =
[#xmlel{name = <<"h1">>, attrs = [],
children = [{xmlcdata, Heading}]},
#xmlel{name = <<"p">>, attrs = [],
children =
[{xmlcdata, <<"An implementation of ">>},
#xmlel{name = <<"a">>,
attrs =
[{<<"href">>,
<<"http://xmpp.org/extensions/xep-0025.html">>}],
children =
[{xmlcdata,
<<"Jabber HTTP Polling (XEP-0025)">>}]}]},
#xmlel{name = <<"p">>, attrs = [],
children =
[{xmlcdata,
<<"This web page is only informative. To "
"use HTTP-Poll you need a Jabber/XMPP "
"client that supports it.">>}]}]}]}.
%%%----------------------------------------------------------------------
%%% Callback functions from gen_fsm
%%%----------------------------------------------------------------------
%%----------------------------------------------------------------------
%% Func: init/1
%% Returns: {ok, StateName, StateData} |
%% {ok, StateName, StateData, Timeout} |
%% ignore |
%% {stop, StopReason}
%%----------------------------------------------------------------------
init([ID, Key, IP]) ->
?INFO_MSG("started: ~p", [{ID, Key, IP}]),
Opts = ejabberd_c2s_config:get_c2s_limits(),
HTTPPollTimeout = ejabberd_config:get_option(
{http_poll_timeout, ?MYNAME},
fun(I) when is_integer(I), I>0 -> I end,
?HTTP_POLL_TIMEOUT) * 1000,
Socket = {http_poll, self(), IP},
ejabberd_socket:start(ejabberd_c2s, ?MODULE, Socket,
Opts),
Timer = erlang:start_timer(HTTPPollTimeout, self(), []),
{ok, loop,
#state{id = ID, key = Key, socket = Socket,
http_poll_timeout = HTTPPollTimeout, timer = Timer}}.
%%----------------------------------------------------------------------
%% Func: StateName/2
%% Returns: {next_state, NextStateName, NextStateData} |
%% {next_state, NextStateName, NextStateData, Timeout} |
%% {stop, Reason, NewStateData}
%% {stop, Reason, NewStateData}
%%----------------------------------------------------------------------
%%----------------------------------------------------------------------
%% Func: StateName/3
%% Returns: {next_state, NextStateName, NextStateData} |
%% {next_state, NextStateName, NextStateData, Timeout} |
%% {reply, Reply, NextStateName, NextStateData} |
%% {reply, Reply, NextStateName, NextStateData, Timeout} |
%% {stop, Reason, NewStateData} |
%% {stop, Reason, Reply, NewStateData}
%% {stop, Reason, Reply, NewStateData}
%%----------------------------------------------------------------------
%state_name(Event, From, StateData) ->
% Reply = ok,
% {reply, Reply, state_name, StateData}.
%%----------------------------------------------------------------------
%% Func: handle_event/3
%% Returns: {next_state, NextStateName, NextStateData} |
%% {next_state, NextStateName, NextStateData, Timeout} |
%% {stop, Reason, NewStateData}
%%----------------------------------------------------------------------
handle_event({activate, From}, StateName, StateData) ->
case StateData#state.input of
<<"">> ->
{next_state, StateName,
StateData#state{waiting_input = {From, ok}}};
Input ->
Receiver = From,
Receiver !
{tcp, StateData#state.socket, Input},
{next_state, StateName,
StateData#state{input = <<"">>, waiting_input = false,
last_receiver = Receiver}}
end;
handle_event(_Event, StateName, StateData) ->
{next_state, StateName, StateData}.
%%----------------------------------------------------------------------
%% Func: handle_sync_event/4
%% Returns: {next_state, NextStateName, NextStateData} |
%% {next_state, NextStateName, NextStateData, Timeout} |
%% {reply, Reply, NextStateName, NextStateData} |
%% {reply, Reply, NextStateName, NextStateData, Timeout} |
%% {stop, Reason, NewStateData} |
%% {stop, Reason, Reply, NewStateData}
%%----------------------------------------------------------------------
handle_sync_event({send, Packet}, _From, StateName,
StateData) ->
Packet2 = iolist_to_binary(Packet),
Output = StateData#state.output ++ [Packet2],
Reply = ok,
{reply, Reply, StateName,
StateData#state{output = Output}};
handle_sync_event(stop, _From, _StateName, StateData) ->
Reply = ok, {stop, normal, Reply, StateData};
handle_sync_event({http_put, Key, NewKey, Packet},
_From, StateName, StateData) ->
Allow = case StateData#state.key of
<<"">> -> true;
OldKey ->
NextKey = jlib:encode_base64((p1_sha:sha1(Key))),
if OldKey == NextKey -> true;
true -> false
end
end,
if Allow ->
case StateData#state.waiting_input of
false ->
Input = <<(StateData#state.input)/binary, Packet/binary>>,
Reply = ok,
{reply, Reply, StateName,
StateData#state{input = Input, key = NewKey}};
{Receiver, _Tag} ->
Receiver !
{tcp, StateData#state.socket, iolist_to_binary(Packet)},
cancel_timer(StateData#state.timer),
Timer =
erlang:start_timer(StateData#state.http_poll_timeout,
self(), []),
Reply = ok,
{reply, Reply, StateName,
StateData#state{waiting_input = false,
last_receiver = Receiver, key = NewKey,
timer = Timer}}
end;
true ->
Reply = {error, bad_key},
{reply, Reply, StateName, StateData}
end;
handle_sync_event(http_get, _From, StateName,
StateData) ->
Reply = {ok, StateData#state.output},
{reply, Reply, StateName,
StateData#state{output = []}};
handle_sync_event(_Event, _From, StateName,
StateData) ->
Reply = ok, {reply, Reply, StateName, StateData}.
code_change(_OldVsn, StateName, StateData, _Extra) ->
{ok, StateName, StateData}.
%%----------------------------------------------------------------------
%% Func: handle_info/3
%% Returns: {next_state, NextStateName, NextStateData} |
%% {next_state, NextStateName, NextStateData, Timeout} |
%% {stop, Reason, NewStateData}
%%----------------------------------------------------------------------
handle_info({timeout, Timer, _}, _StateName,
#state{timer = Timer} = StateData) ->
{stop, normal, StateData};
handle_info(_, StateName, StateData) ->
{next_state, StateName, StateData}.
%%----------------------------------------------------------------------
%% Func: terminate/3
%% Purpose: Shutdown the fsm
%% Returns: any
%%----------------------------------------------------------------------
terminate(_Reason, _StateName, StateData) ->
mnesia:transaction(
fun() ->
mnesia:delete({http_poll, StateData#state.id})
end),
case StateData#state.waiting_input of
false ->
case StateData#state.last_receiver of
undefined -> ok;
Receiver ->
Receiver ! {tcp_closed, StateData#state.socket}
end;
{Receiver, _Tag} ->
Receiver ! {tcp_closed, StateData#state.socket}
end,
catch resend_messages(StateData#state.output),
ok.
%%%----------------------------------------------------------------------
%%% Internal functions
%%%----------------------------------------------------------------------
http_put(ID, Key, NewKey, Packet) ->
case mnesia:dirty_read({http_poll, ID}) of
[] ->
{error, not_exists};
[#http_poll{pid = FsmRef}] ->
gen_fsm:sync_send_all_state_event(
FsmRef, {http_put, Key, NewKey, Packet})
end.
http_get(ID) ->
case mnesia:dirty_read({http_poll, ID}) of
[] ->
{error, not_exists};
[#http_poll{pid = FsmRef}] ->
gen_fsm:sync_send_all_state_event(FsmRef, http_get)
end.
parse_request(Data) ->
Comma = str:chr(Data, $,),
Header = str:substr(Data, 1, Comma - 1),
Packet = str:substr(Data, Comma + 1, byte_size(Data)),
{ID, Key, NewKey} = case str:tokens(Header, <<";">>) of
[ID1] -> {ID1, <<"">>, <<"">>};
[ID1, Key1] -> {ID1, Key1, Key1};
[ID1, Key1, NewKey1] -> {ID1, Key1, NewKey1}
end,
{ok, ID, Key, NewKey, Packet}.
cancel_timer(Timer) ->
erlang:cancel_timer(Timer),
receive {timeout, Timer, _} -> ok after 0 -> ok end.
%% Resend the polled messages
resend_messages(Messages) ->
%% This function is used to resend messages that have been polled but not
%% delivered.
lists:foreach(fun (Packet) -> resend_message(Packet)
end,
Messages).
resend_message(Packet) ->
#xmlel{name = Name} = ParsedPacket =
xml_stream:parse_element(Packet),
if Name == <<"iq">>;
Name == <<"message">>;
Name == <<"presence">> ->
From = get_jid(<<"from">>, ParsedPacket),
To = get_jid(<<"to">>, ParsedPacket),
?DEBUG("Resend ~p ~p ~p~n", [From, To, ParsedPacket]),
ejabberd_router:route(From, To, ParsedPacket);
true -> ok
end.
%% Type can be "from" or "to"
%% Parsed packet is a parsed Jabber packet.
get_jid(Type, ParsedPacket) ->
case xml:get_tag_attr(Type, ParsedPacket) of
{value, StringJid} -> jlib:string_to_jid(StringJid);
false -> jlib:make_jid(<<"">>, <<"">>, <<"">>)
end.
