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 local stream_callbacks = { stream_tag = "http://jabber.org/protocol/httpbind|body" };
  25 local xmlns_bosh = "http://jabber.org/protocol/httpbind"; -- (hard-coded into a literal in session.send)
  26
  27 local BOSH_DEFAULT_HOLD = tonumber(module:get_option("bosh_default_hold")) or 1;
  28 local BOSH_DEFAULT_INACTIVITY = tonumber(module:get_option("bosh_max_inactivity")) or 60;
  29 local BOSH_DEFAULT_POLLING = tonumber(module:get_option("bosh_max_polling")) or 5;
  30 local BOSH_DEFAULT_REQUESTS = tonumber(module:get_option("bosh_max_requests")) or 2;
  31 local BOSH_DEFAULT_MAXPAUSE = tonumber(module:get_option("bosh_max_pause")) or 300;
  32
  33 local default_headers = { ["Content-Type"] = "text/xml; charset=utf-8" };
  34
  35 local t_insert, t_remove, t_concat = table.insert, table.remove, table.concat;
  36 local os_time = os.time;
  37
  38 local sessions = {};
  39 local inactive_sessions = {}; -- Sessions which have no open requests
  40
  41 -- Used to respond to idle sessions (those with waiting requests)
  42 local waiting_requests = {};
  43 function on_destroy_request(request)
  44         waiting_requests[request] = nil;
  45         local session = sessions[request.sid];
  46         if session then
  47                 local requests = session.requests;
  48                 for i,r in pairs(requests) do
  49                         if r == request then requests[i] = nil; break; end
  50                 end
  51
  52                 -- If this session now has no requests open, mark it as inactive
  53                 if #requests == 0 and session.bosh_max_inactive and not inactive_sessions[session] then
  54                         inactive_sessions[session] = os_time();
  55                         (session.log or log)("debug", "BOSH session marked as inactive at %d", inactive_sessions[session]);
  56                 end
  57         end
  58 end
  59
  60 function handle_request(method, body, request)
  61         if (not body) or request.method ~= "POST" then
  62                 return "<html><body>You really don't look like a BOSH client to me... what do you want?</body></html>";
  63         end
  64         if not method then
  65                 log("debug", "Request %s suffered error %s", tostring(request.id), body);
  66                 return;
  67         end
  68         --log("debug", "Handling new request %s: %s\n----------", request.id, tostring(body));
  69         request.notopen = true;
  70         request.log = log;
  71         local parser = lxp.new(init_xmlhandlers(request, stream_callbacks), "|");
  72
  73         parser:parse(body);
  74
  75         local session = sessions[request.sid];
  76         if session then
  77                 local r = session.requests;
  78                 log("debug", "Session %s has %d out of %d requests open", request.sid, #r, session.bosh_hold);
  79                 log("debug", "and there are %d things in the send_buffer", #session.send_buffer);
  80                 if #r > session.bosh_hold then
  81                         -- We are holding too many requests, send what's in the buffer,
  82                         log("debug", "We are holding too many requests, so...");
  83                         if #session.send_buffer > 0 then
  84                                 log("debug", "...sending what is in the buffer")
  85                                 session.send(t_concat(session.send_buffer));
  86                                 session.send_buffer = {};
  87                         else
  88                                 -- or an empty response
  89                                 log("debug", "...sending an empty response");
  90                                 session.send("");
  91                         end
  92                 elseif #session.send_buffer > 0 then
  93                         log("debug", "Session has data in the send buffer, will send now..");
  94                         local resp = t_concat(session.send_buffer);
  95                         session.send_buffer = {};
  96                         session.send(resp);
  97                 end
  98
  99                 if not request.destroyed and session.bosh_wait then
 100                         request.reply_before = os_time() + session.bosh_wait;
 101                         request.on_destroy = on_destroy_request;
 102                         waiting_requests[request] = true;
 103                 end
 104
 105                 log("debug", "Have nothing to say, so leaving request unanswered for now");
 106                 return true;
 107         end
 108 end
 109
 110
 111 local function bosh_reset_stream(session) session.notopen = true; end
 112
 113 local session_close_reply = { headers = default_headers, body = st.stanza("body", { xmlns = xmlns_bosh, type = "terminate" }), attr = {} };
 114 local function bosh_close_stream(session, reason)
 115         (session.log or log)("info", "BOSH client disconnected");
 116         session_close_reply.attr.condition = reason;
 117         local session_close_reply = tostring(session_close_reply);
 118         for _, held_request in ipairs(session.requests) do
 119                 held_request:send(session_close_reply);
 120                 held_request:destroy();
 121         end
 122         sessions[session.sid]  = nil;
 123         sm_destroy_session(session);
 124 end
 125
 126 function stream_callbacks.streamopened(request, attr)
 127         log("debug", "BOSH body open (sid: %s)", attr.sid);
 128         local sid = attr.sid
 129         if not sid then
 130                 -- New session request
 131                 request.notopen = nil; -- Signals that we accept this opening tag
 132
 133                 -- TODO: Sanity checks here (rid, to, known host, etc.)
 134                 if not hosts[attr.to] then
 135                         -- Unknown host
 136                         log("debug", "BOSH client tried to connect to unknown host: %s", tostring(attr.to));
 137                         session_close_reply.body.attr.condition = "host-unknown";
 138                         request:send(session_close_reply);
 139                         request.notopen = nil
 140                         return;
 141                 end
 142
 143                 -- New session
 144                 sid = new_uuid();
 145                 local session = { type = "c2s_unauthed", conn = {}, sid = sid, rid = attr.rid, host = attr.to, bosh_version = attr.ver, bosh_wait = attr.wait, streamid = sid,
 146                                                 bosh_hold = BOSH_DEFAULT_HOLD, bosh_max_inactive = BOSH_DEFAULT_INACTIVITY,
 147                                                 requests = { }, send_buffer = {}, reset_stream = bosh_reset_stream, close = bosh_close_stream,
 148                                                 dispatch_stanza = core_process_stanza, log = logger.init("bosh"..sid), secure = request.secure };
 149                 sessions[sid] = session;
 150
 151                 log("info", "New BOSH session, assigned it sid '%s'", sid);
 152                 local r, send_buffer = session.requests, session.send_buffer;
 153                 local response = { headers = default_headers }
 154                 function session.send(s)
 155                         log("debug", "Sending BOSH data: %s", tostring(s));
 156                         local oldest_request = r[1];
 157                         while oldest_request and oldest_request.destroyed do
 158                                 t_remove(r, 1);
 159                                 waiting_requests[oldest_request] = nil;
 160                                 oldest_request = r[1];
 161                         end
 162                         if oldest_request then
 163                                 log("debug", "We have an open request, so using that to send with");
 164                                 response.body = t_concat{"<body xmlns='http://jabber.org/protocol/httpbind' sid='", sid, "' xmlns:stream = 'http://etherx.jabber.org/streams'>", tostring(s), "</body>" };
 165                                 oldest_request:send(response);
 166                                 --log("debug", "Sent");
 167                                 if oldest_request.stayopen then
 168                                         if #r>1 then
 169                                                 -- Move front request to back
 170                                                 t_insert(r, oldest_request);
 171                                                 t_remove(r, 1);
 172                                         end
 173                                 else
 174                                         log("debug", "Destroying the request now...");
 175                                         oldest_request:destroy();
 176                                         t_remove(r, 1);
 177                                 end
 178                         elseif s ~= "" then
 179                                 log("debug", "Saved to send buffer because there are %d open requests", #r);
 180                                 -- Hmm, no requests are open :(
 181                                 t_insert(session.send_buffer, tostring(s));
 182                                 log("debug", "There are now %d things in the send_buffer", #session.send_buffer);
 183                         end
 184                 end
 185
 186                 -- Send creation response
 187
 188                 local features = st.stanza("stream:features");
 189                 fire_event("stream-features", session, features);
 190                 --xmpp:version='1.0' xmlns:xmpp='urn:xmpp:xbosh'
 191                 local response = st.stanza("body", { xmlns = xmlns_bosh,
 192                                                                         inactivity = tostring(BOSH_DEFAULT_INACTIVITY), polling = tostring(BOSH_DEFAULT_POLLING), requests = tostring(BOSH_DEFAULT_REQUESTS), hold = tostring(session.bosh_hold), maxpause = "120",
 193                                                                         sid = sid, authid = sid, ver  = '1.6', from = session.host, secure = 'true', ["xmpp:version"] = "1.0",
 194                                                                         ["xmlns:xmpp"] = "urn:xmpp:xbosh", ["xmlns:stream"] = "http://etherx.jabber.org/streams" }):add_child(features);
 195                 request:send{ headers = default_headers, body = tostring(response) };
 196
 197                 request.sid = sid;
 198                 return;
 199         end
 200
 201         local session = sessions[sid];
 202         if not session then
 203                 -- Unknown sid
 204                 log("info", "Client tried to use sid '%s' which we don't know about", sid);
 205                 request:send{ headers = default_headers, body = tostring(st.stanza("body", { xmlns = xmlns_bosh, type = "terminate", condition = "item-not-found" })) };
 206                 request.notopen = nil;
 207                 return;
 208         end
 209
 210         if attr.type == "terminate" then
 211                 -- Client wants to end this session
 212                 session:close();
 213                 request.notopen = nil;
 214                 return;
 215         end
 216
 217         -- If session was inactive, make sure it is now marked as not
 218         if #session.requests == 0 then
 219                 (session.log or log)("debug", "BOSH client now active again at %d", os_time());
 220                 inactive_sessions[session] = nil;
 221         end
 222
 223         if session.notopen then
 224                 local features = st.stanza("stream:features");
 225                 fire_event("stream-features", session, features);
 226                 session.send(features);
 227                 session.notopen = nil;
 228         end
 229
 230         request.notopen = nil; -- Signals that we accept this opening tag
 231         t_insert(session.requests, request);
 232         request.sid = sid;
 233 end
 234
 235 function stream_callbacks.handlestanza(request, stanza)
 236         log("debug", "BOSH stanza received: %s\n", stanza:top_tag());
 237         local session = sessions[request.sid];
 238         if session then
 239                 if stanza.attr.xmlns == xmlns_bosh then
 240                         stanza.attr.xmlns = "jabber:client";
 241                 end
 242                 core_process_stanza(session, stanza);
 243         end
 244 end
 245
 246 function on_timer()
 247         -- log("debug", "Checking for requests soon to timeout...");
 248         -- Identify requests timing out within the next few seconds
 249         local now = os_time() + 3;
 250         for request in pairs(waiting_requests) do
 251                 if request.reply_before <= now then
 252                         log("debug", "%s was soon to timeout, sending empty response", request.id);
 253                         -- Send empty response to let the
 254                         -- client know we're still here
 255                         if request.conn then
 256                                 sessions[request.sid].send("");
 257                         end
 258                 end
 259         end
 260
 261         now = now - 3;
 262         for session, inactive_since in pairs(inactive_sessions) do
 263                 if session.bosh_max_inactive then
 264                         if now - inactive_since > session.bosh_max_inactive then
 265                                 (session.log or log)("debug", "BOSH client inactive too long, destroying session at %d", now);
 266                                 sessions[session.sid]  = nil;
 267                                 inactive_sessions[session] = nil;
 268                                 sm_destroy_session(session, "BOSH client silent for over "..session.bosh_max_inactive.." seconds");
 269                         end
 270                 else
 271                         inactive_sessions[session] = nil;
 272                 end
 273         end
 274 end
 275
 276 local ports = module:get_option("bosh_ports") or { 5280 };
 277 httpserver.new_from_config(ports, "http-bind", handle_request);
 278
 279 server.addtimer(on_timer);