1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
|
-- Prosody IM
-- Copyright (C) 2008-2010 Matthew Wild
-- Copyright (C) 2008-2010 Waqas Hussain
--
-- This project is MIT/X11 licensed. Please see the
-- COPYING file in the source package for more information.
--
module:set_global(); -- Global module
local hosts = _G.hosts;
local new_xmpp_stream = require "util.xmppstream".new;
local httpserver = require "net.httpserver";
local sm = require "core.sessionmanager";
local sm_destroy_session = sm.destroy_session;
local new_uuid = require "util.uuid".generate;
local fire_event = prosody.events.fire_event;
local core_process_stanza = core_process_stanza;
local st = require "util.stanza";
local logger = require "util.logger";
local log = logger.init("mod_bosh");
local timer = require "util.timer";
local xmlns_streams = "http://etherx.jabber.org/streams";
local xmlns_xmpp_streams = "urn:ietf:params:xml:ns:xmpp-streams";
local xmlns_bosh = "http://jabber.org/protocol/httpbind"; -- (hard-coded into a literal in session.send)
local stream_callbacks = {
stream_ns = xmlns_bosh, stream_tag = "body", default_ns = "jabber:client" };
local BOSH_DEFAULT_HOLD = module:get_option_number("bosh_default_hold", 1);
local BOSH_DEFAULT_INACTIVITY = module:get_option_number("bosh_max_inactivity", 60);
local BOSH_DEFAULT_POLLING = module:get_option_number("bosh_max_polling", 5);
local BOSH_DEFAULT_REQUESTS = module:get_option_number("bosh_max_requests", 2);
local consider_bosh_secure = module:get_option_boolean("consider_bosh_secure");
local auto_cork = module:get_option_boolean("bosh_auto_cork", false);
local default_headers = { ["Content-Type"] = "text/xml; charset=utf-8" };
local cross_domain = module:get_option("cross_domain_bosh", false);
if cross_domain then
default_headers["Access-Control-Allow-Methods"] = "GET, POST, OPTIONS";
default_headers["Access-Control-Allow-Headers"] = "Content-Type";
default_headers["Access-Control-Max-Age"] = "7200";
if cross_domain == true then
default_headers["Access-Control-Allow-Origin"] = "*";
elseif type(cross_domain) == "table" then
cross_domain = table.concat(cross_domain, ", ");
end
if type(cross_domain) == "string" then
default_headers["Access-Control-Allow-Origin"] = cross_domain;
end
end
local trusted_proxies = module:get_option_set("trusted_proxies", {"127.0.0.1"})._items;
local function get_ip_from_request(request)
local ip = request.conn:ip();
local forwarded_for = request.headers["x-forwarded-for"];
if forwarded_for then
forwarded_for = forwarded_for..", "..ip;
for forwarded_ip in forwarded_for:gmatch("[^%s,]+") do
if not trusted_proxies[forwarded_ip] then
ip = forwarded_ip;
end
end
end
return ip;
end
local t_insert, t_remove, t_concat = table.insert, table.remove, table.concat;
local os_time = os.time;
local sessions = {};
local inactive_sessions = {}; -- Sessions which have no open requests
-- Used to respond to idle sessions (those with waiting requests)
local waiting_requests = {};
function on_destroy_request(request)
log("debug", "Request destroyed: %s", tostring(request));
waiting_requests[request] = nil;
local session = sessions[request.context.sid];
if session then
local requests = session.requests;
for i, r in ipairs(requests) do
if r == request then
t_remove(requests, i);
break;
end
end
-- If this session now has no requests open, mark it as inactive
local max_inactive = session.bosh_max_inactive;
if max_inactive and #requests == 0 then
inactive_sessions[session] = os_time() + max_inactive;
(session.log or log)("debug", "BOSH session marked as inactive (for %ds)", max_inactive);
end
end
end
local function handle_GET(request)
return "<html><body>You really don't look like a BOSH client to me... what do you want?</body></html>";
end
function handle_OPTIONS(request)
local headers = {};
for k,v in pairs(default_headers) do headers[k] = v; end
headers["Content-Type"] = nil;
return { headers = headers, body = "" };
end
function handle_POST(event)
log("debug", "Handling new request %s: %s\n----------", tostring(event.request), tostring(event.request.body));
local request, response = event.request, event.response;
response.on_destroy = on_destroy_request;
local body = request.body;
local context = { request = request, response = response, notopen = true };
local stream = new_xmpp_stream(context, stream_callbacks);
response.context = context;
-- stream:feed() calls the stream_callbacks, so all stanzas in
-- the body are processed in this next line before it returns.
-- In particular, the streamopened() stream callback is where
-- much of the session logic happens, because it's where we first
-- get to see the 'sid' of this request.
stream:feed(body);
-- Stanzas (if any) in the request have now been processed, and
-- we take care of the high-level BOSH logic here, including
-- giving a response or putting the request "on hold".
local session = sessions[context.sid];
if session then
-- Session was marked as inactive, since we have
-- a request open now, unmark it
if inactive_sessions[session] and #session.requests > 0 then
inactive_sessions[session] = nil;
end
local r = session.requests;
log("debug", "Session %s has %d out of %d requests open", context.sid, #r, session.bosh_hold);
log("debug", "and there are %d things in the send_buffer:", #session.send_buffer);
for i, thing in ipairs(session.send_buffer) do
log("debug", " %s", tostring(thing));
end
if #r > session.bosh_hold then
-- We are holding too many requests, send what's in the buffer,
log("debug", "We are holding too many requests, so...");
if #session.send_buffer > 0 then
log("debug", "...sending what is in the buffer")
session.send(t_concat(session.send_buffer));
session.send_buffer = {};
else
-- or an empty response
log("debug", "...sending an empty response");
session.send("");
end
elseif #session.send_buffer > 0 then
log("debug", "Session has data in the send buffer, will send now..");
local resp = t_concat(session.send_buffer);
session.send_buffer = {};
session.send(resp);
end
if not response.finished then
-- We're keeping this request open, to respond later
log("debug", "Have nothing to say, so leaving request unanswered for now");
if session.bosh_wait then
waiting_requests[response] = os_time() + session.bosh_wait;
end
end
if session.bosh_terminate then
session.log("debug", "Closing session with %d requests open", #session.requests);
session:close();
return nil;
else
return true; -- Inform httpserver we shall reply later
end
end
end
local function bosh_reset_stream(session) session.notopen = true; end
local stream_xmlns_attr = { xmlns = "urn:ietf:params:xml:ns:xmpp-streams" };
local function bosh_close_stream(session, reason)
(session.log or log)("info", "BOSH client disconnected");
local close_reply = st.stanza("body", { xmlns = xmlns_bosh, type = "terminate",
["xmlns:stream"] = xmlns_streams });
if reason then
close_reply.attr.condition = "remote-stream-error";
if type(reason) == "string" then -- assume stream error
close_reply:tag("stream:error")
:tag(reason, {xmlns = xmlns_xmpp_streams});
elseif type(reason) == "table" then
if reason.condition then
close_reply:tag("stream:error")
:tag(reason.condition, stream_xmlns_attr):up();
if reason.text then
close_reply:tag("text", stream_xmlns_attr):text(reason.text):up();
end
if reason.extra then
close_reply:add_child(reason.extra);
end
elseif reason.name then -- a stanza
close_reply = reason;
end
end
log("info", "Disconnecting client, <stream:error> is: %s", tostring(close_reply));
end
local response_body = tostring(close_reply);
for _, held_request in ipairs(session.requests) do
held_request.headers = default_headers;
held_request:send(response_body);
end
sessions[session.sid] = nil;
inactive_sessions[session] = nil;
sm_destroy_session(session);
end
-- Handle the <body> tag in the request payload.
function stream_callbacks.streamopened(context, attr)
local request, response = context.request, context.response;
local sid = attr.sid;
log("debug", "BOSH body open (sid: %s)", sid or "<none>");
if not sid then
-- New session request
context.notopen = nil; -- Signals that we accept this opening tag
-- TODO: Sanity checks here (rid, to, known host, etc.)
if not hosts[attr.to] then
-- Unknown host
log("debug", "BOSH client tried to connect to unknown host: %s", tostring(attr.to));
local close_reply = st.stanza("body", { xmlns = xmlns_bosh, type = "terminate",
["xmlns:stream"] = xmlns_streams, condition = "host-unknown" });
response:send(tostring(close_reply));
return;
end
-- New session
sid = new_uuid();
local session = {
type = "c2s_unauthed", conn = {}, sid = sid, rid = tonumber(attr.rid), host = attr.to,
bosh_version = attr.ver, bosh_wait = attr.wait, streamid = sid,
bosh_hold = BOSH_DEFAULT_HOLD, bosh_max_inactive = BOSH_DEFAULT_INACTIVITY,
requests = { }, send_buffer = {}, reset_stream = bosh_reset_stream,
close = bosh_close_stream, dispatch_stanza = core_process_stanza,
log = logger.init("bosh"..sid), secure = consider_bosh_secure or request.secure,
ip = get_ip_from_request(request);
};
sessions[sid] = session;
session.log("debug", "BOSH session created for request from %s", session.ip);
log("info", "New BOSH session, assigned it sid '%s'", sid);
local r, send_buffer = session.requests, session.send_buffer;
function session.send(s)
-- We need to ensure that outgoing stanzas have the jabber:client xmlns
if s.attr and not s.attr.xmlns then
s = st.clone(s);
s.attr.xmlns = "jabber:client";
end
--log("debug", "Sending BOSH data: %s", tostring(s));
local oldest_request = r[1];
if oldest_request and (not(auto_cork) or waiting_requests[oldest_request]) then
log("debug", "We have an open request, so sending on that");
oldest_request.headers = default_headers;
oldest_request:send(t_concat({
"<body xmlns='http://jabber.org/protocol/httpbind' ",
session.bosh_terminate and "type='terminate' " or "",
"sid='", sid, "' xmlns:stream = 'http://etherx.jabber.org/streams'>",
tostring(s),
"</body>"
}));
elseif s ~= "" then
log("debug", "Saved to send buffer because there are %d open requests", #r);
-- Hmm, no requests are open :(
t_insert(session.send_buffer, tostring(s));
log("debug", "There are now %d things in the send_buffer", #session.send_buffer);
end
return true;
end
-- Send creation response
local features = st.stanza("stream:features");
hosts[session.host].events.fire_event("stream-features", { origin = session, features = features });
fire_event("stream-features", session, features);
--xmpp:version='1.0' xmlns:xmpp='urn:xmpp:xbosh'
local body = st.stanza("body", { xmlns = xmlns_bosh,
wait = attr.wait,
inactivity = tostring(BOSH_DEFAULT_INACTIVITY),
polling = tostring(BOSH_DEFAULT_POLLING),
requests = tostring(BOSH_DEFAULT_REQUESTS),
hold = tostring(session.bosh_hold),
sid = sid, authid = sid,
ver = '1.6', from = session.host,
secure = 'true', ["xmpp:version"] = "1.0",
["xmlns:xmpp"] = "urn:xmpp:xbosh",
["xmlns:stream"] = "http://etherx.jabber.org/streams"
}):add_child(features);
response.headers = default_headers;
response:send(tostring(body));
request.sid = sid;
return;
end
local session = sessions[sid];
if not session then
-- Unknown sid
log("info", "Client tried to use sid '%s' which we don't know about", sid);
response.headers = default_headers;
response:send(tostring(st.stanza("body", { xmlns = xmlns_bosh, type = "terminate", condition = "item-not-found" })));
context.notopen = nil;
return;
end
if session.rid then
local rid = tonumber(attr.rid);
local diff = rid - session.rid;
if diff > 1 then
session.log("warn", "rid too large (means a request was lost). Last rid: %d New rid: %s", session.rid, attr.rid);
elseif diff <= 0 then
-- Repeated, ignore
session.log("debug", "rid repeated (on request %s), ignoring: %s (diff %d)", request.id, session.rid, diff);
context.notopen = nil;
context.ignore = true;
context.sid = sid;
t_insert(session.requests, response);
return;
end
session.rid = rid;
end
if attr.type == "terminate" then
-- Client wants to end this session, which we'll do
-- after processing any stanzas in this request
session.bosh_terminate = true;
end
context.notopen = nil; -- Signals that we accept this opening tag
t_insert(session.requests, response);
context.sid = sid;
if session.notopen then
local features = st.stanza("stream:features");
hosts[session.host].events.fire_event("stream-features", { origin = session, features = features });
fire_event("stream-features", session, features);
session.send(features);
session.notopen = nil;
end
end
function stream_callbacks.handlestanza(context, stanza)
if context.ignore then return; end
log("debug", "BOSH stanza received: %s\n", stanza:top_tag());
local session = sessions[context.sid];
if session then
if stanza.attr.xmlns == xmlns_bosh then
stanza.attr.xmlns = nil;
end
core_process_stanza(session, stanza);
end
end
function stream_callbacks.error(context, error)
log("debug", "Error parsing BOSH request payload; %s", error);
if not context.sid then
local response = context.response;
response.headers = default_headers;
response.status_code = 400;
request:send();
return;
end
local session = sessions[context.sid];
if error == "stream-error" then -- Remote stream error, we close normally
session:close();
else
session:close({ condition = "bad-format", text = "Error processing stream" });
end
end
local dead_sessions = {};
function on_timer()
-- log("debug", "Checking for requests soon to timeout...");
-- Identify requests timing out within the next few seconds
local now = os_time() + 3;
for request, reply_before in pairs(waiting_requests) do
if reply_before <= now then
log("debug", "%s was soon to timeout (at %d, now %d), sending empty response", tostring(request), reply_before, now);
-- Send empty response to let the
-- client know we're still here
if request.conn then
sessions[request.context.sid].send("");
end
end
end
now = now - 3;
local n_dead_sessions = 0;
for session, close_after in pairs(inactive_sessions) do
if close_after < now then
(session.log or log)("debug", "BOSH client inactive too long, destroying session at %d", now);
sessions[session.sid] = nil;
inactive_sessions[session] = nil;
n_dead_sessions = n_dead_sessions + 1;
dead_sessions[n_dead_sessions] = session;
end
end
for i=1,n_dead_sessions do
local session = dead_sessions[i];
dead_sessions[i] = nil;
sm_destroy_session(session, "BOSH client silent for over "..session.bosh_max_inactive.." seconds");
end
return 1;
end
module:add_timer(1, on_timer);
function module.add_host(module)
module:depends("http");
module:provides("http", {
default_path = "/http-bind";
route = {
["GET /"] = handle_GET;
["OPTIONS /"] = handle_OPTIONS;
["POST /"] = handle_POST;
};
});
end
|
