plugins/mod_bosh.lua

   1 -- Prosody IM
   2 -- Copyright (C) 2008-2009 Matthew Wild
   3 -- Copyright (C) 2008-2009 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 init_xmlhandlers = require "core.xmlhandlers"
  14 local server = require "net.server";
  15 local httpserver = require "net.httpserver";
  16 local sm = require "core.sessionmanager";
  17 local sm_destroy_session = sm.destroy_session;
  18 local new_uuid = require "util.uuid".generate;
  19 local fire_event = require "core.eventmanager".fire_event;
  20 local core_process_stanza = core_process_stanza;
  21 local st = require "util.stanza";
  22 local logger = require "util.logger";
  23 local log = logger.init("mod_bosh");
  24
  25 local xmlns_bosh = "http://jabber.org/protocol/httpbind"; -- (hard-coded into a literal in session.send)
  26 local stream_callbacks = { stream_ns = "http://jabber.org/protocol/httpbind", stream_tag = "body", default_ns = xmlns_bosh };
  27
  28 local BOSH_DEFAULT_HOLD = tonumber(module:get_option("bosh_default_hold")) or 1;
  29 local BOSH_DEFAULT_INACTIVITY = tonumber(module:get_option("bosh_max_inactivity")) or 60;
  30 local BOSH_DEFAULT_POLLING = tonumber(module:get_option("bosh_max_polling")) or 5;
  31 local BOSH_DEFAULT_REQUESTS = tonumber(module:get_option("bosh_max_requests")) or 2;
  32 local BOSH_DEFAULT_MAXPAUSE = tonumber(module:get_option("bosh_max_pause")) or 300;
  33
  34 local default_headers = { ["Content-Type"] = "text/xml; charset=utf-8" };
  35 local session_close_reply = { headers = default_headers, body = st.stanza("body", { xmlns = xmlns_bosh, type = "terminate" }), attr = {} };
  36
  37 local cross_domain = module:get_option("cross_domain_bosh");
  38 if cross_domain then
  39         default_headers["Access-Control-Allow-Methods"] = "GET, POST, OPTIONS";
  40         default_headers["Access-Control-Allow-Headers"] = "Content-Type";
  41         default_headers["Access-Control-Max-Age"] = "7200";
  42
  43         if cross_domain == true then
  44                 default_headers["Access-Control-Allow-Origin"] = "*";
  45         elseif type(cross_domain) == "table" then
  46                 cross_domain = table.concat(cross_domain, ", ");
  47         end
  48         if type(cross_domain) == "string" then
  49                 default_headers["Access-Control-Allow-Origin"] = cross_domain;
  50         end
  51 end
  52
  53 local t_insert, t_remove, t_concat = table.insert, table.remove, table.concat;
  54 local os_time = os.time;
  55
  56 local sessions = {};
  57 local inactive_sessions = {}; -- Sessions which have no open requests
  58
  59 -- Used to respond to idle sessions (those with waiting requests)
  60 local waiting_requests = {};
  61 function on_destroy_request(request)
  62         waiting_requests[request] = nil;
  63         local session = sessions[request.sid];
  64         if session then
  65                 local requests = session.requests;
  66                 for i,r in pairs(requests) do
  67                         if r == request then requests[i] = nil; break; end
  68                 end
  69
  70                 -- If this session now has no requests open, mark it as inactive
  71                 if #requests == 0 and session.bosh_max_inactive and not inactive_sessions[session] then
  72                         inactive_sessions[session] = os_time();
  73                         (session.log or log)("debug", "BOSH session marked as inactive at %d", inactive_sessions[session]);
  74                 end
  75         end
  76 end
  77
  78 function handle_request(method, body, request)
  79         if (not body) or request.method ~= "POST" then
  80                 if request.method == "OPTIONS" then
  81                         return { headers = default_headers, body = "" };
  82                 else
  83                         return "<html><body>You really don't look like a BOSH client to me... what do you want?</body></html>";
  84                 end
  85         end
  86         if not method then
  87                 log("debug", "Request %s suffered error %s", tostring(request.id), body);
  88                 return;
  89         end
  90         --log("debug", "Handling new request %s: %s\n----------", request.id, tostring(body));
  91         request.notopen = true;
  92         request.log = log;
  93         local parser = lxp.new(init_xmlhandlers(request, stream_callbacks), "\1");
  94
  95         parser:parse(body);
  96
  97         local session = sessions[request.sid];
  98         if session then
  99                 local r = session.requests;
 100                 log("debug", "Session %s has %d out of %d requests open", request.sid, #r, session.bosh_hold);
 101                 log("debug", "and there are %d things in the send_buffer", #session.send_buffer);
 102                 if #r > session.bosh_hold then
 103                         -- We are holding too many requests, send what's in the buffer,
 104                         log("debug", "We are holding too many requests, so...");
 105                         if #session.send_buffer > 0 then
 106                                 log("debug", "...sending what is in the buffer")
 107                                 session.send(t_concat(session.send_buffer));
 108                                 session.send_buffer = {};
 109                         else
 110                                 -- or an empty response
 111                                 log("debug", "...sending an empty response");
 112                                 session.send("");
 113                         end
 114                 elseif #session.send_buffer > 0 then
 115                         log("debug", "Session has data in the send buffer, will send now..");
 116                         local resp = t_concat(session.send_buffer);
 117                         session.send_buffer = {};
 118                         session.send(resp);
 119                 end
 120
 121                 if not request.destroyed and session.bosh_wait then
 122                         request.reply_before = os_time() + session.bosh_wait;
 123                         request.on_destroy = on_destroy_request;
 124                         waiting_requests[request] = true;
 125                 end
 126
 127                 log("debug", "Have nothing to say, so leaving request unanswered for now");
 128                 return true;
 129         end
 130 end
 131
 132
 133 local function bosh_reset_stream(session) session.notopen = true; end
 134
 135 local function bosh_close_stream(session, reason)
 136         (session.log or log)("info", "BOSH client disconnected");
 137         session_close_reply.attr.condition = reason;
 138         for _, held_request in ipairs(session.requests) do
 139                 held_request:send(session_close_reply);
 140                 held_request:destroy();
 141         end
 142         sessions[session.sid]  = nil;
 143         sm_destroy_session(session);
 144 end
 145
 146 function stream_callbacks.streamopened(request, attr)
 147         log("debug", "BOSH body open (sid: %s)", attr.sid);
 148         local sid = attr.sid
 149         if not sid then
 150                 -- New session request
 151                 request.notopen = nil; -- Signals that we accept this opening tag
 152
 153                 -- TODO: Sanity checks here (rid, to, known host, etc.)
 154                 if not hosts[attr.to] then
 155                         -- Unknown host
 156                         log("debug", "BOSH client tried to connect to unknown host: %s", tostring(attr.to));
 157                         session_close_reply.body.attr.condition = "host-unknown";
 158                         request:send(session_close_reply);
 159                         request.notopen = nil
 160                         return;
 161                 end
 162
 163                 -- New session
 164                 sid = new_uuid();
 165                 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,
 166                                                 bosh_hold = BOSH_DEFAULT_HOLD, bosh_max_inactive = BOSH_DEFAULT_INACTIVITY,
 167                                                 requests = { }, send_buffer = {}, reset_stream = bosh_reset_stream, close = bosh_close_stream,
 168                                                 dispatch_stanza = core_process_stanza, log = logger.init("bosh"..sid), secure = request.secure };
 169                 sessions[sid] = session;
 170
 171                 log("info", "New BOSH session, assigned it sid '%s'", sid);
 172                 local r, send_buffer = session.requests, session.send_buffer;
 173                 local response = { headers = default_headers }
 174                 function session.send(s)
 175                         --log("debug", "Sending BOSH data: %s", tostring(s));
 176                         local oldest_request = r[1];
 177                         while oldest_request and oldest_request.destroyed do
 178                                 t_remove(r, 1);
 179                                 waiting_requests[oldest_request] = nil;
 180                                 oldest_request = r[1];
 181                         end
 182                         if oldest_request then
 183                                 log("debug", "We have an open request, so sending on that");
 184                                 response.body = t_concat{"<body xmlns='http://jabber.org/protocol/httpbind' sid='", sid, "' xmlns:stream = 'http://etherx.jabber.org/streams'>", tostring(s), "</body>" };
 185                                 oldest_request:send(response);
 186                                 --log("debug", "Sent");
 187                                 if oldest_request.stayopen then
 188                                         if #r>1 then
 189                                                 -- Move front request to back
 190                                                 t_insert(r, oldest_request);
 191                                                 t_remove(r, 1);
 192                                         end
 193                                 else
 194                                         log("debug", "Destroying the request now...");
 195                                         oldest_request:destroy();
 196                                         t_remove(r, 1);
 197                                 end
 198                         elseif s ~= "" then
 199                                 log("debug", "Saved to send buffer because there are %d open requests", #r);
 200                                 -- Hmm, no requests are open :(
 201                                 t_insert(session.send_buffer, tostring(s));
 202                                 log("debug", "There are now %d things in the send_buffer", #session.send_buffer);
 203                         end
 204                 end
 205
 206                 -- Send creation response
 207
 208                 local features = st.stanza("stream:features");
 209                 hosts[session.host].events.fire_event("stream-features", { origin = session, features = features });
 210                 fire_event("stream-features", session, features);
 211                 --xmpp:version='1.0' xmlns:xmpp='urn:xmpp:xbosh'
 212                 local response = st.stanza("body", { xmlns = xmlns_bosh,
 213                                                                         inactivity = tostring(BOSH_DEFAULT_INACTIVITY), polling = tostring(BOSH_DEFAULT_POLLING), requests = tostring(BOSH_DEFAULT_REQUESTS), hold = tostring(session.bosh_hold), maxpause = "120",
 214                                                                         sid = sid, authid = sid, ver  = '1.6', from = session.host, secure = 'true', ["xmpp:version"] = "1.0",
 215                                                                         ["xmlns:xmpp"] = "urn:xmpp:xbosh", ["xmlns:stream"] = "http://etherx.jabber.org/streams" }):add_child(features);
 216                 request:send{ headers = default_headers, body = tostring(response) };
 217
 218                 request.sid = sid;
 219                 return;
 220         end
 221
 222         local session = sessions[sid];
 223         if not session then
 224                 -- Unknown sid
 225                 log("info", "Client tried to use sid '%s' which we don't know about", sid);
 226                 request:send{ headers = default_headers, body = tostring(st.stanza("body", { xmlns = xmlns_bosh, type = "terminate", condition = "item-not-found" })) };
 227                 request.notopen = nil;
 228                 return;
 229         end
 230
 231         if session.rid then
 232                 local rid = tonumber(attr.rid);
 233                 local diff = rid - session.rid;
 234                 if diff > 1 then
 235                         session.log("warn", "rid too large (means a request was lost). Last rid: %d New rid: %s", session.rid, attr.rid);
 236                 elseif diff <= 0 then
 237                         -- Repeated, ignore
 238                         session.log("debug", "rid repeated (on request %s), ignoring: %d", request.id, session.rid);
 239                         request.notopen = nil;
 240                         t_insert(session.requests, request);
 241                         return;
 242                 end
 243                 session.rid = rid;
 244         end
 245
 246         if attr.type == "terminate" then
 247                 -- Client wants to end this session
 248                 session:close();
 249                 request.notopen = nil;
 250                 return;
 251         end
 252
 253         -- If session was inactive, make sure it is now marked as not
 254         if #session.requests == 0 then
 255                 (session.log or log)("debug", "BOSH client now active again at %d", os_time());
 256                 inactive_sessions[session] = nil;
 257         end
 258
 259         if session.notopen then
 260                 local features = st.stanza("stream:features");
 261                 hosts[session.host].events.fire_event("stream-features", { origin = session, features = features });
 262                 fire_event("stream-features", session, features);
 263                 session.send(features);
 264                 session.notopen = nil;
 265         end
 266
 267         request.notopen = nil; -- Signals that we accept this opening tag
 268         t_insert(session.requests, request);
 269         request.sid = sid;
 270 end
 271
 272 function stream_callbacks.handlestanza(request, stanza)
 273         log("debug", "BOSH stanza received: %s\n", stanza:top_tag());
 274         local session = sessions[request.sid];
 275         if session then
 276                 if stanza.attr.xmlns == xmlns_bosh then
 277                         stanza.attr.xmlns = "jabber:client";
 278                 end
 279                 session.ip = request.handler:ip();
 280                 core_process_stanza(session, stanza);
 281         end
 282 end
 283
 284 local dead_sessions = {};
 285 function on_timer()
 286         -- log("debug", "Checking for requests soon to timeout...");
 287         -- Identify requests timing out within the next few seconds
 288         local now = os_time() + 3;
 289         for request in pairs(waiting_requests) do
 290                 if request.reply_before <= now then
 291                         log("debug", "%s was soon to timeout, sending empty response", request.id);
 292                         -- Send empty response to let the
 293                         -- client know we're still here
 294                         if request.conn then
 295                                 sessions[request.sid].send("");
 296                         end
 297                 end
 298         end
 299
 300         now = now - 3;
 301         local n_dead_sessions = 0;
 302         for session, inactive_since in pairs(inactive_sessions) do
 303                 if session.bosh_max_inactive then
 304                         if now - inactive_since > session.bosh_max_inactive then
 305                                 (session.log or log)("debug", "BOSH client inactive too long, destroying session at %d", now);
 306                                 sessions[session.sid]  = nil;
 307                                 inactive_sessions[session] = nil;
 308                                 n_dead_sessions = n_dead_sessions + 1;
 309                                 dead_sessions[n_dead_sessions] = session;
 310                         end
 311                 else
 312                         inactive_sessions[session] = nil;
 313                 end
 314         end
 315
 316         for i=1,n_dead_sessions do
 317                 local session = dead_sessions[i];
 318                 dead_sessions[i] = nil;
 319                 sm_destroy_session(session, "BOSH client silent for over "..session.bosh_max_inactive.." seconds");
 320         end
 321 end
 322
 323
 324 local function setup()
 325         local ports = module:get_option("bosh_ports") or { 5280 };
 326         httpserver.new_from_config(ports, handle_request, { base = "http-bind" });
 327         server.addtimer(on_timer);
 328 end
 329 if prosody.start_time then -- already started
 330         setup();
 331 else
 332         prosody.events.add_handler("server-started", setup);
 333 end