plugins/mod_bosh.lua

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