plugins/mod_c2s.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:set_global();
  10
  11 local add_task = require "util.timer".add_task;
  12 local new_xmpp_stream = require "util.xmppstream".new;
  13 local nameprep = require "util.encodings".stringprep.nameprep;
  14 local sessionmanager = require "core.sessionmanager";
  15 local st = require "util.stanza";
  16 local sm_new_session, sm_destroy_session = sessionmanager.new_session, sessionmanager.destroy_session;
  17 local uuid_generate = require "util.uuid".generate;
  18 local runner = require "util.async".runner;
  19
  20 local tostring, type = tostring, type;
  21
  22 local xmlns_xmpp_streams = "urn:ietf:params:xml:ns:xmpp-streams";
  23
  24 local log = module._log;
  25
  26 local c2s_timeout = module:get_option_number("c2s_timeout", 300);
  27 local stream_close_timeout = module:get_option_number("c2s_close_timeout", 5);
  28 local opt_keepalives = module:get_option_boolean("c2s_tcp_keepalives", module:get_option_boolean("tcp_keepalives", true));
  29
  30 local measure_connections = module:measure("connections", "amount");
  31 local measure_ipv6 = module:measure("ipv6", "amount");
  32
  33 local sessions = module:shared("sessions");
  34 local core_process_stanza = prosody.core_process_stanza;
  35 local hosts = prosody.hosts;
  36
  37 local stream_callbacks = { default_ns = "jabber:client" };
  38 local listener = {};
  39 local runner_callbacks = {};
  40
  41 module:hook("stats-update", function ()
  42         local count = 0;
  43         local ipv6 = 0;
  44         for _, session in pairs(sessions) do
  45                 count = count + 1;
  46                 if session.ip and session.ip:match(":") then
  47                         ipv6 = ipv6 + 1;
  48                 end
  49         end
  50         measure_connections(count);
  51         measure_ipv6(ipv6);
  52 end);
  53
  54 --- Stream events handlers
  55 local stream_xmlns_attr = {xmlns='urn:ietf:params:xml:ns:xmpp-streams'};
  56
  57 function stream_callbacks.streamopened(session, attr)
  58         local send = session.send;
  59         local host = nameprep(attr.to);
  60         if not host then
  61                 session:close{ condition = "improper-addressing",
  62                         text = "A valid 'to' attribute is required on stream headers" };
  63                 return;
  64         end
  65         if not session.host then
  66                 session.host = host;
  67         elseif session.host ~= host then
  68                 session:close{ condition = "not-authorized",
  69                         text = "The 'to' attribute must remain the same across stream restarts" };
  70                 return;
  71         end
  72         session.version = tonumber(attr.version) or 0;
  73         session.streamid = uuid_generate();
  74         (session.log or log)("debug", "Client sent opening <stream:stream> to %s", session.host);
  75
  76         if not hosts[session.host] or not hosts[session.host].modules.c2s then
  77                 -- We don't serve this host...
  78                 session:close{ condition = "host-unknown", text = "This server does not serve "..tostring(session.host)};
  79                 return;
  80         end
  81
  82         session:open_stream();
  83
  84         (session.log or log)("debug", "Sent reply <stream:stream> to client");
  85         session.notopen = nil;
  86
  87         -- If session.secure is *false* (not nil) then it means we /were/ encrypting
  88         -- since we now have a new stream header, session is secured
  89         if session.secure == false then
  90                 session.secure = true;
  91                 session.encrypted = true;
  92
  93                 local sock = session.conn:socket();
  94                 if sock.info then
  95                         local info = sock:info();
  96                         (session.log or log)("info", "Stream encrypted (%s with %s)", info.protocol, info.cipher);
  97                         session.compressed = info.compression;
  98                 else
  99                         (session.log or log)("info", "Stream encrypted");
 100                 end
 101         end
 102
 103         local features = st.stanza("stream:features");
 104         hosts[session.host].events.fire_event("stream-features", { origin = session, features = features });
 105         if features.tags[1] or session.full_jid then
 106                 send(features);
 107         else
 108                 if session.secure then
 109                         -- Normally STARTTLS would be offered
 110                         (session.log or log)("warn", "No stream features to offer on secure session. Check authentication settings.");
 111                 else
 112                         -- Here SASL should be offered
 113                         (session.log or log)("warn", "No stream features to offer on insecure session. Check encryption and security settings.");
 114                 end
 115                 session:close{ condition = "undefined-condition", text = "No stream features to proceed with" };
 116         end
 117 end
 118
 119 function stream_callbacks.streamclosed(session)
 120         session.log("debug", "Received </stream:stream>");
 121         session:close(false);
 122 end
 123
 124 function stream_callbacks.error(session, error, data)
 125         if error == "no-stream" then
 126                 session.log("debug", "Invalid opening stream header (%s)", (data:gsub("^([^\1]+)\1", "{%1}")));
 127                 session:close("invalid-namespace");
 128         elseif error == "parse-error" then
 129                 (session.log or log)("debug", "Client XML parse error: %s", data);
 130                 session:close("not-well-formed");
 131         elseif error == "stream-error" then
 132                 local condition, text = "undefined-condition";
 133                 for child in data:childtags(nil, xmlns_xmpp_streams) do
 134                         if child.name ~= "text" then
 135                                 condition = child.name;
 136                         else
 137                                 text = child:get_text();
 138                         end
 139                         if condition ~= "undefined-condition" and text then
 140                                 break;
 141                         end
 142                 end
 143                 text = condition .. (text and (" ("..text..")") or "");
 144                 session.log("info", "Session closed by remote with error: %s", text);
 145                 session:close(nil, text);
 146         end
 147 end
 148
 149 function stream_callbacks.handlestanza(session, stanza)
 150         stanza = session.filter("stanzas/in", stanza);
 151         session.thread:run(stanza);
 152 end
 153
 154 --- Session methods
 155 local function session_close(session, reason)
 156         local log = session.log or log;
 157         if session.conn then
 158                 if session.notopen then
 159                         session:open_stream();
 160                 end
 161                 if reason then -- nil == no err, initiated by us, false == initiated by client
 162                         local stream_error = st.stanza("stream:error");
 163                         if type(reason) == "string" then -- assume stream error
 164                                 stream_error:tag(reason, {xmlns = 'urn:ietf:params:xml:ns:xmpp-streams' });
 165                         elseif type(reason) == "table" then
 166                                 if reason.condition then
 167                                         stream_error:tag(reason.condition, stream_xmlns_attr):up();
 168                                         if reason.text then
 169                                                 stream_error:tag("text", stream_xmlns_attr):text(reason.text):up();
 170                                         end
 171                                         if reason.extra then
 172                                                 stream_error:add_child(reason.extra);
 173                                         end
 174                                 elseif reason.name then -- a stanza
 175                                         stream_error = reason;
 176                                 end
 177                         end
 178                         stream_error = tostring(stream_error);
 179                         log("debug", "Disconnecting client, <stream:error> is: %s", stream_error);
 180                         session.send(stream_error);
 181                 end
 182
 183                 session.send("</stream:stream>");
 184                 function session.send() return false; end
 185
 186                 local reason_text = (reason and (reason.name or reason.text or reason.condition)) or reason;
 187                 session.log("debug", "c2s stream for %s closed: %s", session.full_jid or session.ip or "<unknown>", reason_text or "session closed");
 188
 189                 -- Authenticated incoming stream may still be sending us stanzas, so wait for </stream:stream> from remote
 190                 local conn = session.conn;
 191                 if reason_text == nil and not session.notopen and session.type == "c2s" then
 192                         -- Grace time to process data from authenticated cleanly-closed stream
 193                         add_task(stream_close_timeout, function ()
 194                                 if not session.destroyed then
 195                                         session.log("warn", "Failed to receive a stream close response, closing connection anyway...");
 196                                         sm_destroy_session(session, reason_text);
 197                                         conn:close();
 198                                 end
 199                         end);
 200                 else
 201                         sm_destroy_session(session, reason_text);
 202                         conn:close();
 203                 end
 204         else
 205                 local reason_text = (reason and (reason.name or reason.text or reason.condition)) or reason;
 206                 sm_destroy_session(session, reason_text);
 207         end
 208 end
 209
 210 module:hook_global("user-deleted", function(event)
 211         local username, host = event.username, event.host;
 212         local user = hosts[host].sessions[username];
 213         if user and user.sessions then
 214                 for _, session in pairs(user.sessions) do
 215                         session:close{ condition = "not-authorized", text = "Account deleted" };
 216                 end
 217         end
 218 end, 200);
 219
 220 module:hook_global("user-password-changed", function(event)
 221         local username, host, resource = event.username, event.host, event.resource;
 222         local user = hosts[host].sessions[username];
 223         if user and user.sessions then
 224                 for r, session in pairs(user.sessions) do
 225                         if r ~= resource then
 226                                 session:close{ condition = "reset", text = "Password changed" };
 227                         end
 228                 end
 229         end
 230 end, 200);
 231
 232 function runner_callbacks:ready()
 233         self.data.conn:resume();
 234 end
 235
 236 function runner_callbacks:waiting()
 237         self.data.conn:pause();
 238 end
 239
 240 function runner_callbacks:error(err)
 241         (self.data.log or log)("error", "Traceback[c2s]: %s", err);
 242 end
 243
 244 --- Port listener
 245 function listener.onconnect(conn)
 246         local session = sm_new_session(conn);
 247
 248         session.log("info", "Client connected");
 249
 250         -- Client is using legacy SSL (otherwise mod_tls sets this flag)
 251         if conn:ssl() then
 252                 session.secure = true;
 253                 session.encrypted = true;
 254
 255                 -- Check if TLS compression is used
 256                 local sock = conn:socket();
 257                 if sock.info then
 258                         session.compressed = sock:info"compression";
 259                 end
 260         end
 261
 262         if opt_keepalives then
 263                 conn:setoption("keepalive", opt_keepalives);
 264         end
 265
 266         session.close = session_close;
 267
 268         local stream = new_xmpp_stream(session, stream_callbacks);
 269         session.stream = stream;
 270         session.notopen = true;
 271
 272         function session.reset_stream()
 273                 session.notopen = true;
 274                 session.stream:reset();
 275         end
 276
 277         session.thread = runner(function (stanza)
 278                 core_process_stanza(session, stanza);
 279         end, runner_callbacks, session);
 280
 281         local filter = session.filter;
 282         function session.data(data)
 283                 -- Parse the data, which will store stanzas in session.pending_stanzas
 284                 if data then
 285                         data = filter("bytes/in", data);
 286                         if data then
 287                                 local ok, err = stream:feed(data);
 288                                 if not ok then
 289                                         log("debug", "Received invalid XML (%s) %d bytes: %q", err, #data, data:sub(1, 300));
 290                                         session:close("not-well-formed");
 291                                 end
 292                         end
 293                 end
 294         end
 295
 296         if c2s_timeout then
 297                 add_task(c2s_timeout, function ()
 298                         if session.type == "c2s_unauthed" then
 299                                 session:close("connection-timeout");
 300                         end
 301                 end);
 302         end
 303
 304         session.dispatch_stanza = stream_callbacks.handlestanza;
 305
 306         sessions[conn] = session;
 307 end
 308
 309 function listener.onincoming(conn, data)
 310         local session = sessions[conn];
 311         if session then
 312                 session.data(data);
 313         end
 314 end
 315
 316 function listener.ondisconnect(conn, err)
 317         local session = sessions[conn];
 318         if session then
 319                 (session.log or log)("info", "Client disconnected: %s", err or "connection closed");
 320                 sm_destroy_session(session, err);
 321                 session.conn = nil;
 322                 sessions[conn]  = nil;
 323         end
 324 end
 325
 326 function listener.onreadtimeout(conn)
 327         local session = sessions[conn];
 328         if session then
 329                 return (hosts[session.host] or prosody).events.fire_event("c2s-read-timeout", { session = session });
 330         end
 331 end
 332
 333 function listener.ondrain(conn)
 334         local session = sessions[conn];
 335         if session then
 336                 return (hosts[session.host] or prosody).events.fire_event("c2s-ondrain", { session = session });
 337         end
 338 end
 339
 340 local function keepalive(event)
 341         local session = event.session;
 342         if not session.notopen then
 343                 return event.session.send(' ');
 344         end
 345 end
 346
 347 function listener.associate_session(conn, session)
 348         sessions[conn] = session;
 349 end
 350
 351 function module.add_host(module)
 352         module:hook("c2s-read-timeout", keepalive, -1);
 353 end
 354
 355 module:hook("c2s-read-timeout", keepalive, -1);
 356
 357 module:hook("server-stopping", function(event)
 358         local reason = event.reason;
 359         for _, session in pairs(sessions) do
 360                 session:close{ condition = "system-shutdown", text = reason };
 361         end
 362 end, -100);
 363
 364
 365
 366 module:provides("net", {
 367         name = "c2s";
 368         listener = listener;
 369         default_port = 5222;
 370         encryption = "starttls";
 371         multiplex = {
 372                 pattern = "^<.*:stream.*%sxmlns%s*=%s*(['\"])jabber:client%1.*>";
 373         };
 374 });
 375
 376 module:provides("net", {
 377         name = "legacy_ssl";
 378         listener = listener;
 379         encryption = "ssl";
 380         multiplex = {
 381                 pattern = "^<.*:stream.*%sxmlns%s*=%s*(['\"])jabber:client%1.*>";
 382         };
 383 });
 384
 385