plugins/mod_bosh.lua

   1
   2 module.host = "*" -- Global module
   3
   4 local lxp = require "lxp";
   5 local init_xmlhandlers = require "core.xmlhandlers"
   6 local server = require "net.server";
   7 local httpserver = require "net.httpserver";
   8 local sm = require "core.sessionmanager";
   9 local sm_destroy_session = sm.destroy_session;
  10 local new_uuid = require "util.uuid".generate;
  11 local fire_event = require "core.eventmanager".fire_event;
  12 local core_process_stanza = core_process_stanza;
  13 local st = require "util.stanza";
  14 local logger = require "util.logger";
  15 local log = logger.init("mod_bosh");
  16 local stream_callbacks = { stream_tag = "http://jabber.org/protocol/httpbind|body" };
  17 local config = require "core.configmanager";
  18 local xmlns_bosh = "http://jabber.org/protocol/httpbind"; -- (hard-coded into a literal in session.send)
  19
  20 local BOSH_DEFAULT_HOLD = tonumber(config.get("*", "core", "bosh_default_hold")) or 1;
  21 local BOSH_DEFAULT_INACTIVITY = tonumber(config.get("*", "core", "bosh_max_inactivity")) or 60;
  22 local BOSH_DEFAULT_POLLING = tonumber(config.get("*", "core", "bosh_max_polling")) or 5;
  23 local BOSH_DEFAULT_REQUESTS = tonumber(config.get("*", "core", "bosh_max_requests")) or 2;
  24 local BOSH_DEFAULT_MAXPAUSE = tonumber(config.get("*", "core", "bosh_max_pause")) or 300;
  25
  26 local default_headers = { ["Content-Type"] = "text/xml; charset=utf-8" };
  27
  28 local t_insert, t_remove, t_concat = table.insert, table.remove, table.concat;
  29 local os_time = os.time;
  30
  31 local sessions = {};
  32 local inactive_sessions = {}; -- Sessions which have no open requests
  33
  34 -- Used to respond to idle sessions (those with waiting requests)
  35 local waiting_requests = {};
  36 function on_destroy_request(request)
  37         waiting_requests[request] = nil;
  38         local session = sessions[request.sid];
  39         if session then
  40                 local requests = session.requests;
  41                 for i,r in pairs(requests) do
  42                         if r == request then requests[i] = nil; break; end
  43                 end
  44
  45                 -- If this session now has no requests open, mark it as inactive
  46                 if #requests == 0 and session.bosh_max_inactive and not inactive_sessions[session] then
  47                         inactive_sessions[session] = os_time();
  48                         (session.log or log)("debug", "BOSH session marked as inactive at %d", inactive_sessions[session]);
  49                 end
  50         end
  51 end
  52
  53 function handle_request(method, body, request)
  54         if (not body) or request.method ~= "POST" then
  55                 return "<html><body>You really don't look like a BOSH client to me... what do you want?</body></html>";
  56         end
  57         if not method then
  58                 log("debug", "Request %s suffered error %s", tostring(request.id), body);
  59                 return;
  60         end
  61         --log("debug", "Handling new request %s: %s\n----------", request.id, tostring(body));
  62         request.notopen = true;
  63         request.log = log;
  64         local parser = lxp.new(init_xmlhandlers(request, stream_callbacks), "|");
  65
  66         parser:parse(body);
  67
  68         local session = sessions[request.sid];
  69         if session then
  70                 local r = session.requests;
  71                 log("debug", "Session %s has %d out of %d requests open", request.sid, #r, session.bosh_hold);
  72                 log("debug", "and there are %d things in the send_buffer", #session.send_buffer);
  73                 if #r > session.bosh_hold then
  74                         -- We are holding too many requests, send what's in the buffer,
  75                         log("debug", "We are holding too many requests, so...");
  76                         if #session.send_buffer > 0 then
  77                                 log("debug", "...sending what is in the buffer")
  78                                 session.send(t_concat(session.send_buffer));
  79                                 session.send_buffer = {};
  80                         else
  81                                 -- or an empty response
  82                                 log("debug", "...sending an empty response");
  83                                 session.send("");
  84                         end
  85                 elseif #session.send_buffer > 0 then
  86                         log("debug", "Session has data in the send buffer, will send now..");
  87                         local resp = t_concat(session.send_buffer);
  88                         session.send_buffer = {};
  89                         session.send(resp);
  90                 end
  91
  92                 if not request.destroyed and session.bosh_wait then
  93                         request.reply_before = os_time() + session.bosh_wait;
  94                         request.on_destroy = on_destroy_request;
  95                         waiting_requests[request] = true;
  96                 end
  97
  98                 log("debug", "Have nothing to say, so leaving request unanswered for now");
  99                 return true;
 100         end
 101 end
 102
 103
 104 local function bosh_reset_stream(session) session.notopen = true; end
 105
 106 local session_close_reply = { headers = default_headers, body = st.stanza("body", { xmlns = xmlns_bosh, type = "terminate" }), attr = {} };
 107 local function bosh_close_stream(session, reason)
 108         (session.log or log)("info", "BOSH client disconnected");
 109         session_close_reply.attr.condition = reason;
 110         local session_close_reply = tostring(session_close_reply);
 111         for _, held_request in ipairs(session.requests) do
 112                 held_request:send(session_close_reply);
 113                 held_request:destroy();
 114         end
 115         sessions[session.sid]  = nil;
 116         sm_destroy_session(session);
 117 end
 118
 119 function stream_callbacks.streamopened(request, attr)
 120         log("debug", "BOSH body open (sid: %s)", attr.sid);
 121         local sid = attr.sid
 122         if not sid then
 123                 -- New session request
 124                 request.notopen = nil; -- Signals that we accept this opening tag
 125
 126                 -- TODO: Sanity checks here (rid, to, known host, etc.)
 127                 if not hosts[attr.to] then
 128                         -- Unknown host
 129                         log("debug", "BOSH client tried to connect to unknown host: %s", tostring(attr.to));
 130                         session_close_reply.attr.condition = "host-unknown";
 131                         request:send{ headers = default_headers, body = tostring(session_close_reply) };
 132                         request.notopen = nil
 133                         return;
 134                 end
 135
 136                 -- New session
 137                 sid = new_uuid();
 138                 local session = { type = "c2s_unauthed", conn = {}, sid = sid, rid = attr.rid, host = attr.to, bosh_version = attr.ver, bosh_wait = attr.wait, streamid = sid,
 139                                                 bosh_hold = BOSH_DEFAULT_HOLD, bosh_max_inactive = BOSH_DEFAULT_INACTIVITY,
 140                                                 requests = { }, send_buffer = {}, reset_stream = bosh_reset_stream, close = bosh_close_stream,
 141                                                 dispatch_stanza = core_process_stanza, log = logger.init("bosh"..sid) };
 142                 sessions[sid] = session;
 143
 144                 log("info", "New BOSH session, assigned it sid '%s'", sid);
 145                 local r, send_buffer = session.requests, session.send_buffer;
 146                 local response = { headers = default_headers }
 147                 function session.send(s)
 148                         log("debug", "Sending BOSH data: %s", tostring(s));
 149                         local oldest_request = r[1];
 150                         while oldest_request and oldest_request.destroyed do
 151                                 t_remove(r, 1);
 152                                 waiting_requests[oldest_request] = nil;
 153                                 oldest_request = r[1];
 154                         end
 155                         if oldest_request then
 156                                 log("debug", "We have an open request, so using that to send with");
 157                                 response.body = t_concat{"<body xmlns='http://jabber.org/protocol/httpbind' sid='", sid, "' xmlns:stream = 'http://etherx.jabber.org/streams'>", tostring(s), "</body>" };
 158                                 oldest_request:send(response);
 159                                 --log("debug", "Sent");
 160                                 if oldest_request.stayopen then
 161                                         if #r>1 then
 162                                                 -- Move front request to back
 163                                                 t_insert(r, oldest_request);
 164                                                 t_remove(r, 1);
 165                                         end
 166                                 else
 167                                         log("debug", "Destroying the request now...");
 168                                         oldest_request:destroy();
 169                                         t_remove(r, 1);
 170                                 end
 171                         elseif s ~= "" then
 172                                 log("debug", "Saved to send buffer because there are %d open requests", #r);
 173                                 -- Hmm, no requests are open :(
 174                                 t_insert(session.send_buffer, tostring(s));
 175                                 log("debug", "There are now %d things in the send_buffer", #session.send_buffer);
 176                         end
 177                 end
 178
 179                 -- Send creation response
 180
 181                 local features = st.stanza("stream:features");
 182                 fire_event("stream-features", session, features);
 183                 --xmpp:version='1.0' xmlns:xmpp='urn:xmpp:xbosh'
 184                 local response = st.stanza("body", { xmlns = xmlns_bosh,
 185                                                                         inactivity = tostring(BOSH_DEFAULT_INACTIVITY), polling = tostring(BOSH_DEFAULT_POLLING), requests = tostring(BOSH_DEFAULT_REQUESTS), hold = tostring(session.bosh_hold), maxpause = "120",
 186                                                                         sid = sid, authid = sid, ver  = '1.6', from = session.host, secure = 'true', ["xmpp:version"] = "1.0",
 187                                                                         ["xmlns:xmpp"] = "urn:xmpp:xbosh", ["xmlns:stream"] = "http://etherx.jabber.org/streams" }):add_child(features);
 188                 request:send{ headers = default_headers, body = tostring(response) };
 189
 190                 request.sid = sid;
 191                 return;
 192         end
 193
 194         local session = sessions[sid];
 195         if not session then
 196                 -- Unknown sid
 197                 log("info", "Client tried to use sid '%s' which we don't know about", sid);
 198                 request:send{ headers = default_headers, body = tostring(st.stanza("body", { xmlns = xmlns_bosh, type = "terminate", condition = "item-not-found" })) };
 199                 request.notopen = nil;
 200                 return;
 201         end
 202
 203         if attr.type == "terminate" then
 204                 -- Client wants to end this session
 205                 session:close();
 206                 request.notopen = nil;
 207                 return;
 208         end
 209
 210         -- If session was inactive, make sure it is now marked as not
 211         if #session.requests == 0 then
 212                 (session.log or log)("debug", "BOSH client now active again at %d", os_time());
 213                 inactive_sessions[session] = nil;
 214         end
 215
 216         if session.notopen then
 217                 local features = st.stanza("stream:features");
 218                 fire_event("stream-features", session, features);
 219                 session.send(features);
 220                 session.notopen = nil;
 221         end
 222
 223         request.notopen = nil; -- Signals that we accept this opening tag
 224         t_insert(session.requests, request);
 225         request.sid = sid;
 226 end
 227
 228 function stream_callbacks.handlestanza(request, stanza)
 229         log("debug", "BOSH stanza received: %s\n", stanza:top_tag());
 230         local session = sessions[request.sid];
 231         if session then
 232                 if stanza.attr.xmlns == xmlns_bosh then
 233                         stanza.attr.xmlns = "jabber:client";
 234                 end
 235                 core_process_stanza(session, stanza);
 236         end
 237 end
 238
 239 function on_timer()
 240         -- log("debug", "Checking for requests soon to timeout...");
 241         -- Identify requests timing out within the next few seconds
 242         local now = os_time() + 3;
 243         for request in pairs(waiting_requests) do
 244                 if request.reply_before <= now then
 245                         log("debug", "%s was soon to timeout, sending empty response", request.id);
 246                         -- Send empty response to let the
 247                         -- client know we're still here
 248                         if request.conn then
 249                                 sessions[request.sid].send("");
 250                         end
 251                 end
 252         end
 253
 254         now = now - 3;
 255         for session, inactive_since in pairs(inactive_sessions) do
 256                 if session.bosh_max_inactive then
 257                         if now - inactive_since > session.bosh_max_inactive then
 258                                 (session.log or log)("debug", "BOSH client inactive too long, destroying session at %d", now);
 259                                 sessions[session.sid]  = nil;
 260                                 inactive_sessions[session] = nil;
 261                                 sm_destroy_session(session, "BOSH client silent for over "..session.bosh_max_inactive.." seconds");
 262                         end
 263                 else
 264                         inactive_sessions[session] = nil;
 265                 end
 266         end
 267 end
 268
 269 local ports = config.get(module.host, "core", "bosh_ports") or { 5280 };
 270 for _, options in ipairs(ports) do
 271         local port, base, ssl, interface = 5280, "http-bind", false, nil;
 272         if type(options) == "number" then
 273                 port = options;
 274         elseif type(options) == "table" then
 275                 port, base, ssl, interface = options.port or 5280, options.path or "http-bind", options.ssl or false, options.interface;
 276         elseif type(options) == "string" then
 277                 base = options;
 278         end
 279         httpserver.new{ port = port, base = base, handler = handle_request, ssl = ssl }
 280 end
 281
 282 server.addtimer(on_timer);