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