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 consider_bosh_secure = module:get_option_boolean("consider_bosh_secure");
  35
  36 local default_headers = { ["Content-Type"] = "text/xml; charset=utf-8" };
  37 local session_close_reply = { headers = default_headers, body = st.stanza("body", { xmlns = xmlns_bosh, type = "terminate" }), attr = {} };
  38
  39 local cross_domain = module:get_option("cross_domain_bosh");
  40 if cross_domain then
  41         default_headers["Access-Control-Allow-Methods"] = "GET, POST, OPTIONS";
  42         default_headers["Access-Control-Allow-Headers"] = "Content-Type";
  43         default_headers["Access-Control-Max-Age"] = "7200";
  44
  45         if cross_domain == true then
  46                 default_headers["Access-Control-Allow-Origin"] = "*";
  47         elseif type(cross_domain) == "table" then
  48                 cross_domain = table.concat(cross_domain, ", ");
  49         end
  50         if type(cross_domain) == "string" then
  51                 default_headers["Access-Control-Allow-Origin"] = cross_domain;
  52         end
  53 end
  54
  55 local t_insert, t_remove, t_concat = table.insert, table.remove, table.concat;
  56 local os_time = os.time;
  57
  58 local sessions = {};
  59 local inactive_sessions = {}; -- Sessions which have no open requests
  60
  61 -- Used to respond to idle sessions (those with waiting requests)
  62 local waiting_requests = {};
  63 function on_destroy_request(request)
  64         waiting_requests[request] = nil;
  65         local session = sessions[request.sid];
  66         if session then
  67                 local requests = session.requests;
  68                 for i,r in ipairs(requests) do
  69                         if r == request then
  70                                 t_remove(requests, i);
  71                                 break;
  72                         end
  73                 end
  74
  75                 -- If this session now has no requests open, mark it as inactive
  76                 if #requests == 0 and session.bosh_max_inactive and not inactive_sessions[session] then
  77                         inactive_sessions[session] = os_time();
  78                         (session.log or log)("debug", "BOSH session marked as inactive at %d", inactive_sessions[session]);
  79                 end
  80         end
  81 end
  82
  83 function handle_request(method, body, request)
  84         if (not body) or request.method ~= "POST" then
  85                 if request.method == "OPTIONS" then
  86                         return { headers = default_headers, body = "" };
  87                 else
  88                         return "<html><body>You really don't look like a BOSH client to me... what do you want?</body></html>";
  89                 end
  90         end
  91         if not method then
  92                 log("debug", "Request %s suffered error %s", tostring(request.id), body);
  93                 return;
  94         end
  95         --log("debug", "Handling new request %s: %s\n----------", request.id, tostring(body));
  96         request.notopen = true;
  97         request.log = log;
  98         request.on_destroy = on_destroy_request;
  99
 100         local parser = lxp.new(init_xmlhandlers(request, stream_callbacks), "\1");
 101
 102         parser:parse(body);
 103
 104         local session = sessions[request.sid];
 105         if session then
 106                 local r = session.requests;
 107                 log("debug", "Session %s has %d out of %d requests open", request.sid, #r, session.bosh_hold);
 108                 log("debug", "and there are %d things in the send_buffer", #session.send_buffer);
 109                 if #r > session.bosh_hold then
 110                         -- We are holding too many requests, send what's in the buffer,
 111                         log("debug", "We are holding too many requests, so...");
 112                         if #session.send_buffer > 0 then
 113                                 log("debug", "...sending what is in the buffer")
 114                                 session.send(t_concat(session.send_buffer));
 115                                 session.send_buffer = {};
 116                         else
 117                                 -- or an empty response
 118                                 log("debug", "...sending an empty response");
 119                                 session.send("");
 120                         end
 121                 elseif #session.send_buffer > 0 then
 122                         log("debug", "Session has data in the send buffer, will send now..");
 123                         local resp = t_concat(session.send_buffer);
 124                         session.send_buffer = {};
 125                         session.send(resp);
 126                 end
 127
 128                 if not request.destroyed then
 129                         -- We're keeping this request open, to respond later
 130                         log("debug", "Have nothing to say, so leaving request unanswered for now");
 131                         if session.bosh_wait then
 132                                 request.reply_before = os_time() + session.bosh_wait;
 133                                 waiting_requests[request] = true;
 134                         end
 135                         if inactive_sessions[session] then
 136                                 -- Session was marked as inactive, since we have
 137                                 -- a request open now, unmark it
 138                                 inactive_sessions[session] = nil;
 139                         end
 140                 end
 141
 142                 return true; -- Inform httpserver we shall reply later
 143         end
 144 end
 145
 146
 147 local function bosh_reset_stream(session) session.notopen = true; end
 148
 149 local function bosh_close_stream(session, reason)
 150         (session.log or log)("info", "BOSH client disconnected");
 151         session_close_reply.attr.condition = reason;
 152         for _, held_request in ipairs(session.requests) do
 153                 held_request:send(session_close_reply);
 154                 held_request:destroy();
 155         end
 156         sessions[session.sid]  = nil;
 157         sm_destroy_session(session);
 158 end
 159
 160 function stream_callbacks.streamopened(request, attr)
 161         log("debug", "BOSH body open (sid: %s)", attr.sid);
 162         local sid = attr.sid
 163         if not sid then
 164                 -- New session request
 165                 request.notopen = nil; -- Signals that we accept this opening tag
 166
 167                 -- TODO: Sanity checks here (rid, to, known host, etc.)
 168                 if not hosts[attr.to] then
 169                         -- Unknown host
 170                         log("debug", "BOSH client tried to connect to unknown host: %s", tostring(attr.to));
 171                         session_close_reply.body.attr.condition = "host-unknown";
 172                         request:send(session_close_reply);
 173                         request.notopen = nil
 174                         return;
 175                 end
 176
 177                 -- New session
 178                 sid = new_uuid();
 179                 local session = {
 180                         type = "c2s_unauthed", conn = {}, sid = sid, rid = tonumber(attr.rid)-1, host = attr.to,
 181                         bosh_version = attr.ver, bosh_wait = attr.wait, streamid = sid,
 182                         bosh_hold = BOSH_DEFAULT_HOLD, bosh_max_inactive = BOSH_DEFAULT_INACTIVITY,
 183                         requests = { }, send_buffer = {}, reset_stream = bosh_reset_stream,
 184                         close = bosh_close_stream, dispatch_stanza = core_process_stanza,
 185                         log = logger.init("bosh"..sid), secure = consider_bosh_secure or request.secure
 186                 };
 187                 sessions[sid] = session;
 188
 189                 log("info", "New BOSH session, assigned it sid '%s'", sid);
 190                 local r, send_buffer = session.requests, session.send_buffer;
 191                 local response = { headers = default_headers }
 192                 function session.send(s)
 193                         --log("debug", "Sending BOSH data: %s", tostring(s));
 194                         local oldest_request = r[1];
 195                         if oldest_request then
 196                                 log("debug", "We have an open request, so sending on that");
 197                                 response.body = t_concat{"<body xmlns='http://jabber.org/protocol/httpbind' sid='", sid, "' xmlns:stream = 'http://etherx.jabber.org/streams'>", tostring(s), "</body>" };
 198                                 oldest_request:send(response);
 199                                 --log("debug", "Sent");
 200                                 if oldest_request.stayopen then
 201                                         if #r>1 then
 202                                                 -- Move front request to back
 203                                                 t_insert(r, oldest_request);
 204                                                 t_remove(r, 1);
 205                                         end
 206                                 else
 207                                         log("debug", "Destroying the request now...");
 208                                         oldest_request:destroy();
 209                                 end
 210                         elseif s ~= "" then
 211                                 log("debug", "Saved to send buffer because there are %d open requests", #r);
 212                                 -- Hmm, no requests are open :(
 213                                 t_insert(session.send_buffer, tostring(s));
 214                                 log("debug", "There are now %d things in the send_buffer", #session.send_buffer);
 215                         end
 216                 end
 217
 218                 -- Send creation response
 219
 220                 local features = st.stanza("stream:features");
 221                 hosts[session.host].events.fire_event("stream-features", { origin = session, features = features });
 222                 fire_event("stream-features", session, features);
 223                 --xmpp:version='1.0' xmlns:xmpp='urn:xmpp:xbosh'
 224                 local response = st.stanza("body", { xmlns = xmlns_bosh,
 225                                                                         inactivity = tostring(BOSH_DEFAULT_INACTIVITY), polling = tostring(BOSH_DEFAULT_POLLING), requests = tostring(BOSH_DEFAULT_REQUESTS), hold = tostring(session.bosh_hold), maxpause = "120",
 226                                                                         sid = sid, authid = sid, ver  = '1.6', from = session.host, secure = 'true', ["xmpp:version"] = "1.0",
 227                                                                         ["xmlns:xmpp"] = "urn:xmpp:xbosh", ["xmlns:stream"] = "http://etherx.jabber.org/streams" }):add_child(features);
 228                 request:send{ headers = default_headers, body = tostring(response) };
 229
 230                 request.sid = sid;
 231                 return;
 232         end
 233
 234         local session = sessions[sid];
 235         if not session then
 236                 -- Unknown sid
 237                 log("info", "Client tried to use sid '%s' which we don't know about", sid);
 238                 request:send{ headers = default_headers, body = tostring(st.stanza("body", { xmlns = xmlns_bosh, type = "terminate", condition = "item-not-found" })) };
 239                 request.notopen = nil;
 240                 return;
 241         end
 242
 243         if session.rid then
 244                 local rid = tonumber(attr.rid);
 245                 local diff = rid - session.rid;
 246                 if diff > 1 then
 247                         session.log("warn", "rid too large (means a request was lost). Last rid: %d New rid: %s", session.rid, attr.rid);
 248                 elseif diff <= 0 then
 249                         -- Repeated, ignore
 250                         session.log("debug", "rid repeated (on request %s), ignoring: %s (diff %d)", request.id, session.rid, diff);
 251                         request.notopen = nil;
 252                         request.sid = sid;
 253                         t_insert(session.requests, request);
 254                         return;
 255                 end
 256                 session.rid = rid;
 257         end
 258
 259         if attr.type == "terminate" then
 260                 -- Client wants to end this session
 261                 session:close();
 262                 request.notopen = nil;
 263                 return;
 264         end
 265
 266         if session.notopen then
 267                 local features = st.stanza("stream:features");
 268                 hosts[session.host].events.fire_event("stream-features", { origin = session, features = features });
 269                 fire_event("stream-features", session, features);
 270                 session.send(features);
 271                 session.notopen = nil;
 272         end
 273
 274         request.notopen = nil; -- Signals that we accept this opening tag
 275         t_insert(session.requests, request);
 276         request.sid = sid;
 277 end
 278
 279 function stream_callbacks.handlestanza(request, stanza)
 280         log("debug", "BOSH stanza received: %s\n", stanza:top_tag());
 281         local session = sessions[request.sid];
 282         if session then
 283                 if stanza.attr.xmlns == xmlns_bosh then
 284                         stanza.attr.xmlns = nil;
 285                 end
 286                 session.ip = request.handler:ip();
 287                 core_process_stanza(session, stanza);
 288         end
 289 end
 290
 291 local dead_sessions = {};
 292 function on_timer()
 293         -- log("debug", "Checking for requests soon to timeout...");
 294         -- Identify requests timing out within the next few seconds
 295         local now = os_time() + 3;
 296         for request in pairs(waiting_requests) do
 297                 if request.reply_before <= now then
 298                         log("debug", "%s was soon to timeout, sending empty response", request.id);
 299                         -- Send empty response to let the
 300                         -- client know we're still here
 301                         if request.conn then
 302                                 sessions[request.sid].send("");
 303                         end
 304                 end
 305         end
 306
 307         now = now - 3;
 308         local n_dead_sessions = 0;
 309         for session, inactive_since in pairs(inactive_sessions) do
 310                 if session.bosh_max_inactive then
 311                         if now - inactive_since > session.bosh_max_inactive then
 312                                 (session.log or log)("debug", "BOSH client inactive too long, destroying session at %d", now);
 313                                 sessions[session.sid]  = nil;
 314                                 inactive_sessions[session] = nil;
 315                                 n_dead_sessions = n_dead_sessions + 1;
 316                                 dead_sessions[n_dead_sessions] = session;
 317                         end
 318                 else
 319                         inactive_sessions[session] = nil;
 320                 end
 321         end
 322
 323         for i=1,n_dead_sessions do
 324                 local session = dead_sessions[i];
 325                 dead_sessions[i] = nil;
 326                 sm_destroy_session(session, "BOSH client silent for over "..session.bosh_max_inactive.." seconds");
 327         end
 328 end
 329
 330
 331 local function setup()
 332         local ports = module:get_option("bosh_ports") or { 5280 };
 333         httpserver.new_from_config(ports, handle_request, { base = "http-bind" });
 334         server.addtimer(on_timer);
 335 end
 336 if prosody.start_time then -- already started
 337         setup();
 338 else
 339         prosody.events.add_handler("server-started", setup);
 340 end