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 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 = "jabber:client" };
  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 ipairs(requests) do
  67                         if r == request then
  68                                 t_remove(requests, i);
  69                                 break;
  70                         end
  71                 end
  72
  73                 -- If this session now has no requests open, mark it as inactive
  74                 if #requests == 0 and session.bosh_max_inactive and not inactive_sessions[session] then
  75                         inactive_sessions[session] = os_time();
  76                         (session.log or log)("debug", "BOSH session marked as inactive at %d", inactive_sessions[session]);
  77                 end
  78         end
  79 end
  80
  81 function handle_request(method, body, request)
  82         if (not body) or request.method ~= "POST" then
  83                 if request.method == "OPTIONS" then
  84                         return { headers = default_headers, body = "" };
  85                 else
  86                         return "<html><body>You really don't look like a BOSH client to me... what do you want?</body></html>";
  87                 end
  88         end
  89         if not method then
  90                 log("debug", "Request %s suffered error %s", tostring(request.id), body);
  91                 return;
  92         end
  93         --log("debug", "Handling new request %s: %s\n----------", request.id, tostring(body));
  94         request.notopen = true;
  95         request.log = log;
  96         request.on_destroy = on_destroy_request;
  97
  98         local parser = lxp.new(init_xmlhandlers(request, stream_callbacks), "\1");
  99
 100         parser:parse(body);
 101
 102         local session = sessions[request.sid];
 103         if session then
 104                 local r = session.requests;
 105                 log("debug", "Session %s has %d out of %d requests open", request.sid, #r, session.bosh_hold);
 106                 log("debug", "and there are %d things in the send_buffer", #session.send_buffer);
 107                 if #r > session.bosh_hold then
 108                         -- We are holding too many requests, send what's in the buffer,
 109                         log("debug", "We are holding too many requests, so...");
 110                         if #session.send_buffer > 0 then
 111                                 log("debug", "...sending what is in the buffer")
 112                                 session.send(t_concat(session.send_buffer));
 113                                 session.send_buffer = {};
 114                         else
 115                                 -- or an empty response
 116                                 log("debug", "...sending an empty response");
 117                                 session.send("");
 118                         end
 119                 elseif #session.send_buffer > 0 then
 120                         log("debug", "Session has data in the send buffer, will send now..");
 121                         local resp = t_concat(session.send_buffer);
 122                         session.send_buffer = {};
 123                         session.send(resp);
 124                 end
 125
 126                 if not request.destroyed then
 127                         -- We're keeping this request open, to respond later
 128                         log("debug", "Have nothing to say, so leaving request unanswered for now");
 129                         if session.bosh_wait then
 130                                 request.reply_before = os_time() + session.bosh_wait;
 131                                 waiting_requests[request] = true;
 132                         end
 133                         if inactive_sessions[session] then
 134                                 -- Session was marked as inactive, since we have
 135                                 -- a request open now, unmark it
 136                                 inactive_sessions[session] = nil;
 137                         end
 138                 end
 139
 140                 return true; -- Inform httpserver we shall reply later
 141         end
 142 end
 143
 144
 145 local function bosh_reset_stream(session) session.notopen = true; end
 146
 147 local function bosh_close_stream(session, reason)
 148         (session.log or log)("info", "BOSH client disconnected");
 149         session_close_reply.attr.condition = reason;
 150         for _, held_request in ipairs(session.requests) do
 151                 held_request:send(session_close_reply);
 152                 held_request:destroy();
 153         end
 154         sessions[session.sid]  = nil;
 155         sm_destroy_session(session);
 156 end
 157
 158 function stream_callbacks.streamopened(request, attr)
 159         log("debug", "BOSH body open (sid: %s)", attr.sid);
 160         local sid = attr.sid
 161         if not sid then
 162                 -- New session request
 163                 request.notopen = nil; -- Signals that we accept this opening tag
 164
 165                 -- TODO: Sanity checks here (rid, to, known host, etc.)
 166                 if not hosts[attr.to] then
 167                         -- Unknown host
 168                         log("debug", "BOSH client tried to connect to unknown host: %s", tostring(attr.to));
 169                         session_close_reply.body.attr.condition = "host-unknown";
 170                         request:send(session_close_reply);
 171                         request.notopen = nil
 172                         return;
 173                 end
 174
 175                 -- New session
 176                 sid = new_uuid();
 177                 local session = { type = "c2s_unauthed", conn = {}, sid = sid, rid = tonumber(attr.rid)-1, host = attr.to, bosh_version = attr.ver, bosh_wait = attr.wait, streamid = sid,
 178                                                 bosh_hold = BOSH_DEFAULT_HOLD, bosh_max_inactive = BOSH_DEFAULT_INACTIVITY,
 179                                                 requests = { }, send_buffer = {}, reset_stream = bosh_reset_stream, close = bosh_close_stream,
 180                                                 dispatch_stanza = core_process_stanza, log = logger.init("bosh"..sid), secure = request.secure };
 181                 sessions[sid] = session;
 182
 183                 log("info", "New BOSH session, assigned it sid '%s'", sid);
 184                 local r, send_buffer = session.requests, session.send_buffer;
 185                 local response = { headers = default_headers }
 186                 function session.send(s)
 187                         --log("debug", "Sending BOSH data: %s", tostring(s));
 188                         local oldest_request = r[1];
 189                         if oldest_request then
 190                                 log("debug", "We have an open request, so sending on that");
 191                                 response.body = t_concat{"<body xmlns='http://jabber.org/protocol/httpbind' sid='", sid, "' xmlns:stream = 'http://etherx.jabber.org/streams'>", tostring(s), "</body>" };
 192                                 oldest_request:send(response);
 193                                 --log("debug", "Sent");
 194                                 if oldest_request.stayopen then
 195                                         if #r>1 then
 196                                                 -- Move front request to back
 197                                                 t_insert(r, oldest_request);
 198                                                 t_remove(r, 1);
 199                                         end
 200                                 else
 201                                         log("debug", "Destroying the request now...");
 202                                         oldest_request:destroy();
 203                                 end
 204                         elseif s ~= "" then
 205                                 log("debug", "Saved to send buffer because there are %d open requests", #r);
 206                                 -- Hmm, no requests are open :(
 207                                 t_insert(session.send_buffer, tostring(s));
 208                                 log("debug", "There are now %d things in the send_buffer", #session.send_buffer);
 209                         end
 210                 end
 211
 212                 -- Send creation response
 213
 214                 local features = st.stanza("stream:features");
 215                 hosts[session.host].events.fire_event("stream-features", { origin = session, features = features });
 216                 fire_event("stream-features", session, features);
 217                 --xmpp:version='1.0' xmlns:xmpp='urn:xmpp:xbosh'
 218                 local response = st.stanza("body", { xmlns = xmlns_bosh,
 219                                                                         inactivity = tostring(BOSH_DEFAULT_INACTIVITY), polling = tostring(BOSH_DEFAULT_POLLING), requests = tostring(BOSH_DEFAULT_REQUESTS), hold = tostring(session.bosh_hold), maxpause = "120",
 220                                                                         sid = sid, authid = sid, ver  = '1.6', from = session.host, secure = 'true', ["xmpp:version"] = "1.0",
 221                                                                         ["xmlns:xmpp"] = "urn:xmpp:xbosh", ["xmlns:stream"] = "http://etherx.jabber.org/streams" }):add_child(features);
 222                 request:send{ headers = default_headers, body = tostring(response) };
 223
 224                 request.sid = sid;
 225                 return;
 226         end
 227
 228         local session = sessions[sid];
 229         if not session then
 230                 -- Unknown sid
 231                 log("info", "Client tried to use sid '%s' which we don't know about", sid);
 232                 request:send{ headers = default_headers, body = tostring(st.stanza("body", { xmlns = xmlns_bosh, type = "terminate", condition = "item-not-found" })) };
 233                 request.notopen = nil;
 234                 return;
 235         end
 236
 237         if session.rid then
 238                 local rid = tonumber(attr.rid);
 239                 local diff = rid - session.rid;
 240                 if diff > 1 then
 241                         session.log("warn", "rid too large (means a request was lost). Last rid: %d New rid: %s", session.rid, attr.rid);
 242                 elseif diff <= 0 then
 243                         -- Repeated, ignore
 244                         session.log("debug", "rid repeated (on request %s), ignoring: %s (diff %d)", request.id, session.rid, diff);
 245                         request.notopen = nil;
 246                         request.sid = sid;
 247                         t_insert(session.requests, request);
 248                         return;
 249                 end
 250                 session.rid = rid;
 251         end
 252
 253         if attr.type == "terminate" then
 254                 -- Client wants to end this session
 255                 session:close();
 256                 request.notopen = nil;
 257                 return;
 258         end
 259
 260         if session.notopen then
 261                 local features = st.stanza("stream:features");
 262                 hosts[session.host].events.fire_event("stream-features", { origin = session, features = features });
 263                 fire_event("stream-features", session, features);
 264                 session.send(features);
 265                 session.notopen = nil;
 266         end
 267
 268         request.notopen = nil; -- Signals that we accept this opening tag
 269         t_insert(session.requests, request);
 270         request.sid = sid;
 271 end
 272
 273 function stream_callbacks.handlestanza(request, stanza)
 274         log("debug", "BOSH stanza received: %s\n", stanza:top_tag());
 275         local session = sessions[request.sid];
 276         if session then
 277                 if stanza.attr.xmlns == xmlns_bosh then
 278                         stanza.attr.xmlns = nil;
 279                 end
 280                 session.ip = request.handler:ip();
 281                 core_process_stanza(session, stanza);
 282         end
 283 end
 284
 285 local dead_sessions = {};
 286 function on_timer()
 287         -- log("debug", "Checking for requests soon to timeout...");
 288         -- Identify requests timing out within the next few seconds
 289         local now = os_time() + 3;
 290         for request in pairs(waiting_requests) do
 291                 if request.reply_before <= now then
 292                         log("debug", "%s was soon to timeout, sending empty response", request.id);
 293                         -- Send empty response to let the
 294                         -- client know we're still here
 295                         if request.conn then
 296                                 sessions[request.sid].send("");
 297                         end
 298                 end
 299         end
 300
 301         now = now - 3;
 302         local n_dead_sessions = 0;
 303         for session, inactive_since in pairs(inactive_sessions) do
 304                 if session.bosh_max_inactive then
 305                         if now - inactive_since > session.bosh_max_inactive then
 306                                 (session.log or log)("debug", "BOSH client inactive too long, destroying session at %d", now);
 307                                 sessions[session.sid]  = nil;
 308                                 inactive_sessions[session] = nil;
 309                                 n_dead_sessions = n_dead_sessions + 1;
 310                                 dead_sessions[n_dead_sessions] = session;
 311                         end
 312                 else
 313                         inactive_sessions[session] = nil;
 314                 end
 315         end
 316
 317         for i=1,n_dead_sessions do
 318                 local session = dead_sessions[i];
 319                 dead_sessions[i] = nil;
 320                 sm_destroy_session(session, "BOSH client silent for over "..session.bosh_max_inactive.." seconds");
 321         end
 322 end
 323
 324
 325 local function setup()
 326         local ports = module:get_option("bosh_ports") or { 5280 };
 327         httpserver.new_from_config(ports, handle_request, { base = "http-bind" });
 328         server.addtimer(on_timer);
 329 end
 330 if prosody.start_time then -- already started
 331         setup();
 332 else
 333         prosody.events.add_handler("server-started", setup);
 334 end