Merge Tobias->trunk
[prosody.git] / plugins / mod_bosh.lua
1 -- Prosody IM
2 -- Copyright (C) 2008-2010 Matthew Wild
3 -- Copyright (C) 2008-2010 Waqas Hussain
4 -- 
5 -- This project is MIT/X11 licensed. Please see the
6 -- COPYING file in the source package for more information.
7 --
8
9 module.host = "*" -- Global module
10
11 local hosts = _G.hosts;
12 local lxp = require "lxp";
13 local new_xmpp_stream = require "util.xmppstream".new;
14 local httpserver = require "net.httpserver";
15 local sm = require "core.sessionmanager";
16 local sm_destroy_session = sm.destroy_session;
17 local new_uuid = require "util.uuid".generate;
18 local fire_event = prosody.events.fire_event;
19 local core_process_stanza = core_process_stanza;
20 local st = require "util.stanza";
21 local logger = require "util.logger";
22 local log = logger.init("mod_bosh");
23 local timer = require "util.timer";
24
25 local xmlns_streams = "http://etherx.jabber.org/streams";
26 local xmlns_xmpp_streams = "urn:ietf:params:xml:ns:xmpp-streams";
27 local xmlns_bosh = "http://jabber.org/protocol/httpbind"; -- (hard-coded into a literal in session.send)
28
29 local stream_callbacks = {
30         stream_ns = xmlns_bosh, stream_tag = "body", default_ns = "jabber:client" };
31
32 local BOSH_DEFAULT_HOLD = tonumber(module:get_option("bosh_default_hold")) or 1;
33 local BOSH_DEFAULT_INACTIVITY = tonumber(module:get_option("bosh_max_inactivity")) or 60;
34 local BOSH_DEFAULT_POLLING = tonumber(module:get_option("bosh_max_polling")) or 5;
35 local BOSH_DEFAULT_REQUESTS = tonumber(module:get_option("bosh_max_requests")) or 2;
36
37 local consider_bosh_secure = module:get_option_boolean("consider_bosh_secure");
38
39 local default_headers = { ["Content-Type"] = "text/xml; charset=utf-8" };
40
41 local cross_domain = module:get_option("cross_domain_bosh");
42 if cross_domain then
43         default_headers["Access-Control-Allow-Methods"] = "GET, POST, OPTIONS";
44         default_headers["Access-Control-Allow-Headers"] = "Content-Type";
45         default_headers["Access-Control-Max-Age"] = "7200";
46
47         if cross_domain == true then
48                 default_headers["Access-Control-Allow-Origin"] = "*";
49         elseif type(cross_domain) == "table" then
50                 cross_domain = table.concat(cross_domain, ", ");
51         end
52         if type(cross_domain) == "string" then
53                 default_headers["Access-Control-Allow-Origin"] = cross_domain;
54         end
55 end
56
57 local trusted_proxies = module:get_option_set("trusted_proxies", {"127.0.0.1"})._items;
58
59 local function get_ip_from_request(request)
60         local ip = request.handler:ip();
61         local forwarded_for = request.headers["x-forwarded-for"];
62         if forwarded_for then
63                 forwarded_for = forwarded_for..", "..ip;
64                 for forwarded_ip in forwarded_for:gmatch("[^%s,]+") do
65                         if not trusted_proxies[forwarded_ip] then
66                                 ip = forwarded_ip;
67                         end
68                 end
69         end
70         return ip;
71 end
72
73 local t_insert, t_remove, t_concat = table.insert, table.remove, table.concat;
74 local os_time = os.time;
75
76 local sessions = {};
77 local inactive_sessions = {}; -- Sessions which have no open requests
78
79 -- Used to respond to idle sessions (those with waiting requests)
80 local waiting_requests = {};
81 function on_destroy_request(request)
82         waiting_requests[request] = nil;
83         local session = sessions[request.sid];
84         if session then
85                 local requests = session.requests;
86                 for i,r in ipairs(requests) do
87                         if r == request then
88                                 t_remove(requests, i);
89                                 break;
90                         end
91                 end
92                 
93                 -- If this session now has no requests open, mark it as inactive
94                 if #requests == 0 and session.bosh_max_inactive and not inactive_sessions[session] then
95                         inactive_sessions[session] = os_time();
96                         (session.log or log)("debug", "BOSH session marked as inactive at %d", inactive_sessions[session]);
97                 end
98         end
99 end
100
101 function handle_request(method, body, request)
102         if (not body) or request.method ~= "POST" then
103                 if request.method == "OPTIONS" then
104                         local headers = {};
105                         for k,v in pairs(default_headers) do headers[k] = v; end
106                         headers["Content-Type"] = nil;
107                         return { headers = headers, body = "" };
108                 else
109                         return "<html><body>You really don't look like a BOSH client to me... what do you want?</body></html>";
110                 end
111         end
112         if not method then
113                 log("debug", "Request %s suffered error %s", tostring(request.id), body);
114                 return;
115         end
116         --log("debug", "Handling new request %s: %s\n----------", request.id, tostring(body));
117         request.notopen = true;
118         request.log = log;
119         request.on_destroy = on_destroy_request;
120         
121         local stream = new_xmpp_stream(request, stream_callbacks);
122         -- stream:feed() calls the stream_callbacks, so all stanzas in
123         -- the body are processed in this next line before it returns.
124         stream:feed(body);
125         
126         local session = sessions[request.sid];
127         if session then
128                 local r = session.requests;
129                 log("debug", "Session %s has %d out of %d requests open", request.sid, #r, session.bosh_hold);
130                 log("debug", "and there are %d things in the send_buffer", #session.send_buffer);
131                 if #r > session.bosh_hold then
132                         -- We are holding too many requests, send what's in the buffer,
133                         log("debug", "We are holding too many requests, so...");
134                         if #session.send_buffer > 0 then
135                                 log("debug", "...sending what is in the buffer")
136                                 session.send(t_concat(session.send_buffer));
137                                 session.send_buffer = {};
138                         else
139                                 -- or an empty response
140                                 log("debug", "...sending an empty response");
141                                 session.send("");
142                         end
143                 elseif #session.send_buffer > 0 then
144                         log("debug", "Session has data in the send buffer, will send now..");
145                         local resp = t_concat(session.send_buffer);
146                         session.send_buffer = {};
147                         session.send(resp);
148                 end
149                 
150                 if not request.destroyed then
151                         -- We're keeping this request open, to respond later
152                         log("debug", "Have nothing to say, so leaving request unanswered for now");
153                         if session.bosh_wait then
154                                 request.reply_before = os_time() + session.bosh_wait;
155                                 waiting_requests[request] = true;
156                         end
157                         if inactive_sessions[session] then
158                                 -- Session was marked as inactive, since we have
159                                 -- a request open now, unmark it
160                                 inactive_sessions[session] = nil;
161                         end
162                 end
163                 
164                 return true; -- Inform httpserver we shall reply later
165         end
166 end
167
168
169 local function bosh_reset_stream(session) session.notopen = true; end
170
171 local stream_xmlns_attr = { xmlns = "urn:ietf:params:xml:ns:xmpp-streams" };
172
173 local function bosh_close_stream(session, reason)
174         (session.log or log)("info", "BOSH client disconnected");
175         
176         local close_reply = st.stanza("body", { xmlns = xmlns_bosh, type = "terminate",
177                 ["xmlns:streams"] = xmlns_streams });
178         
179
180         if reason then
181                 close_reply.attr.condition = "remote-stream-error";
182                 if type(reason) == "string" then -- assume stream error
183                         close_reply:tag("stream:error")
184                                 :tag(reason, {xmlns = xmlns_xmpp_streams});
185                 elseif type(reason) == "table" then
186                         if reason.condition then
187                                 close_reply:tag("stream:error")
188                                         :tag(reason.condition, stream_xmlns_attr):up();
189                                 if reason.text then
190                                         close_reply:tag("text", stream_xmlns_attr):text(reason.text):up();
191                                 end
192                                 if reason.extra then
193                                         close_reply:add_child(reason.extra);
194                                 end
195                         elseif reason.name then -- a stanza
196                                 close_reply = reason;
197                         end
198                 end
199                 log("info", "Disconnecting client, <stream:error> is: %s", tostring(close_reply));
200         end
201
202         local session_close_response = { headers = default_headers, body = tostring(close_reply) };
203
204         --FIXME: Quite sure we shouldn't reply to all requests with the error
205         for _, held_request in ipairs(session.requests) do
206                 held_request:send(session_close_response);
207                 held_request:destroy();
208         end
209         sessions[session.sid]  = nil;
210         sm_destroy_session(session);
211 end
212
213 function stream_callbacks.streamopened(request, attr)
214         log("debug", "BOSH body open (sid: %s)", attr.sid);
215         local sid = attr.sid
216         if not sid then
217                 -- New session request
218                 request.notopen = nil; -- Signals that we accept this opening tag
219                 
220                 -- TODO: Sanity checks here (rid, to, known host, etc.)
221                 if not hosts[attr.to] then
222                         -- Unknown host
223                         log("debug", "BOSH client tried to connect to unknown host: %s", tostring(attr.to));
224                         local close_reply = st.stanza("body", { xmlns = xmlns_bosh, type = "terminate",
225                                 ["xmlns:streams"] = xmlns_streams, condition = "host-unknown" });
226                         request:send(tostring(close_reply));
227                         return;
228                 end
229                 
230                 -- New session
231                 sid = new_uuid();
232                 local session = {
233                         type = "c2s_unauthed", conn = {}, sid = sid, rid = tonumber(attr.rid), host = attr.to,
234                         bosh_version = attr.ver, bosh_wait = attr.wait, streamid = sid,
235                         bosh_hold = BOSH_DEFAULT_HOLD, bosh_max_inactive = BOSH_DEFAULT_INACTIVITY,
236                         requests = { }, send_buffer = {}, reset_stream = bosh_reset_stream,
237                         close = bosh_close_stream, dispatch_stanza = core_process_stanza,
238                         log = logger.init("bosh"..sid), secure = consider_bosh_secure or request.secure,
239                         ip = get_ip_from_request(request);
240                 };
241                 sessions[sid] = session;
242                 
243                 session.log("debug", "BOSH session created for request from %s", session.ip);
244                 log("info", "New BOSH session, assigned it sid '%s'", sid);
245                 local r, send_buffer = session.requests, session.send_buffer;
246                 local response = { headers = default_headers }
247                 function session.send(s)
248                         -- We need to ensure that outgoing stanzas have the jabber:client xmlns
249                         if s.attr and not s.attr.xmlns then
250                                 s = st.clone(s);
251                                 s.attr.xmlns = "jabber:client";
252                         end
253                         --log("debug", "Sending BOSH data: %s", tostring(s));
254                         local oldest_request = r[1];
255                         if oldest_request then
256                                 log("debug", "We have an open request, so sending on that");
257                                 response.body = t_concat{"<body xmlns='http://jabber.org/protocol/httpbind' sid='", sid, "' xmlns:stream = 'http://etherx.jabber.org/streams'>", tostring(s), "</body>" };
258                                 oldest_request:send(response);
259                                 --log("debug", "Sent");
260                                 if oldest_request.stayopen then
261                                         if #r>1 then
262                                                 -- Move front request to back
263                                                 t_insert(r, oldest_request);
264                                                 t_remove(r, 1);
265                                         end
266                                 else
267                                         log("debug", "Destroying the request now...");
268                                         oldest_request:destroy();
269                                 end
270                         elseif s ~= "" then
271                                 log("debug", "Saved to send buffer because there are %d open requests", #r);
272                                 -- Hmm, no requests are open :(
273                                 t_insert(session.send_buffer, tostring(s));
274                                 log("debug", "There are now %d things in the send_buffer", #session.send_buffer);
275                         end
276                 end
277                 
278                 -- Send creation response
279                 
280                 local features = st.stanza("stream:features");
281                 hosts[session.host].events.fire_event("stream-features", { origin = session, features = features });
282                 fire_event("stream-features", session, features);
283                 --xmpp:version='1.0' xmlns:xmpp='urn:xmpp:xbosh'
284                 local response = st.stanza("body", { xmlns = xmlns_bosh,
285                         wait = attr.wait,
286                         inactivity = tostring(BOSH_DEFAULT_INACTIVITY),
287                         polling = tostring(BOSH_DEFAULT_POLLING),
288                         requests = tostring(BOSH_DEFAULT_REQUESTS),
289                         hold = tostring(session.bosh_hold),
290                         sid = sid, authid = sid,
291                         ver  = '1.6', from = session.host,
292                         secure = 'true', ["xmpp:version"] = "1.0",
293                         ["xmlns:xmpp"] = "urn:xmpp:xbosh",
294                         ["xmlns:stream"] = "http://etherx.jabber.org/streams"
295                 }):add_child(features);
296                 request:send{ headers = default_headers, body = tostring(response) };
297                 
298                 request.sid = sid;
299                 return;
300         end
301         
302         local session = sessions[sid];
303         if not session then
304                 -- Unknown sid
305                 log("info", "Client tried to use sid '%s' which we don't know about", sid);
306                 request:send{ headers = default_headers, body = tostring(st.stanza("body", { xmlns = xmlns_bosh, type = "terminate", condition = "item-not-found" })) };
307                 request.notopen = nil;
308                 return;
309         end
310         
311         if session.rid then
312                 local rid = tonumber(attr.rid);
313                 local diff = rid - session.rid;
314                 if diff > 1 then
315                         session.log("warn", "rid too large (means a request was lost). Last rid: %d New rid: %s", session.rid, attr.rid);
316                 elseif diff <= 0 then
317                         -- Repeated, ignore
318                         session.log("debug", "rid repeated (on request %s), ignoring: %s (diff %d)", request.id, session.rid, diff);
319                         request.notopen = nil;
320                         request.ignore = true;
321                         request.sid = sid;
322                         t_insert(session.requests, request);
323                         return;
324                 end
325                 session.rid = rid;
326         end
327         
328         if attr.type == "terminate" then
329                 -- Client wants to end this session
330                 session:close();
331                 request.notopen = nil;
332                 return;
333         end
334         
335         if session.notopen then
336                 local features = st.stanza("stream:features");
337                 hosts[session.host].events.fire_event("stream-features", { origin = session, features = features });
338                 fire_event("stream-features", session, features);
339                 session.send(features);
340                 session.notopen = nil;
341         end
342         
343         request.notopen = nil; -- Signals that we accept this opening tag
344         t_insert(session.requests, request);
345         request.sid = sid;
346 end
347
348 function stream_callbacks.handlestanza(request, stanza)
349         if request.ignore then return; end
350         log("debug", "BOSH stanza received: %s\n", stanza:top_tag());
351         local session = sessions[request.sid];
352         if session then
353                 if stanza.attr.xmlns == xmlns_bosh then
354                         stanza.attr.xmlns = nil;
355                 end
356                 core_process_stanza(session, stanza);
357         end
358 end
359
360 function stream_callbacks.error(request, error)
361         log("debug", "Error parsing BOSH request payload; %s", error);
362         if not request.sid then
363                 request:send({ headers = default_headers, status = "400 Bad Request" });
364                 return;
365         end
366         
367         local session = sessions[request.sid];
368         if error == "stream-error" then -- Remote stream error, we close normally
369                 session:close();
370         else
371                 session:close({ condition = "bad-format", text = "Error processing stream" });
372         end
373 end
374
375 local dead_sessions = {};
376 function on_timer()
377         -- log("debug", "Checking for requests soon to timeout...");
378         -- Identify requests timing out within the next few seconds
379         local now = os_time() + 3;
380         for request in pairs(waiting_requests) do
381                 if request.reply_before <= now then
382                         log("debug", "%s was soon to timeout, sending empty response", request.id);
383                         -- Send empty response to let the
384                         -- client know we're still here
385                         if request.conn then
386                                 sessions[request.sid].send("");
387                         end
388                 end
389         end
390         
391         now = now - 3;
392         local n_dead_sessions = 0;
393         for session, inactive_since in pairs(inactive_sessions) do
394                 if session.bosh_max_inactive then
395                         if now - inactive_since > session.bosh_max_inactive then
396                                 (session.log or log)("debug", "BOSH client inactive too long, destroying session at %d", now);
397                                 sessions[session.sid]  = nil;
398                                 inactive_sessions[session] = nil;
399                                 n_dead_sessions = n_dead_sessions + 1;
400                                 dead_sessions[n_dead_sessions] = session;
401                         end
402                 else
403                         inactive_sessions[session] = nil;
404                 end
405         end
406
407         for i=1,n_dead_sessions do
408                 local session = dead_sessions[i];
409                 dead_sessions[i] = nil;
410                 sm_destroy_session(session, "BOSH client silent for over "..session.bosh_max_inactive.." seconds");
411         end
412         return 1;
413 end
414
415
416 local function setup()
417         local ports = module:get_option("bosh_ports") or { 5280 };
418         httpserver.new_from_config(ports, handle_request, { base = "http-bind" });
419         timer.add_task(1, on_timer);
420 end
421 if prosody.start_time then -- already started
422         setup();
423 else
424         prosody.events.add_handler("server-started", setup);
425 end