plugins/mod_s2s/mod_s2s.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 prosody = prosody;
  12 local hosts = prosody.hosts;
  13 local core_process_stanza = prosody.core_process_stanza;
  14
  15 local tostring, type = tostring, type;
  16 local t_insert = table.insert;
  17 local xpcall, traceback = xpcall, debug.traceback;
  18 local NULL = {};
  19
  20 local add_task = require "util.timer".add_task;
  21 local st = require "util.stanza";
  22 local initialize_filters = require "util.filters".initialize;
  23 local nameprep = require "util.encodings".stringprep.nameprep;
  24 local new_xmpp_stream = require "util.xmppstream".new;
  25 local s2s_new_incoming = require "core.s2smanager".new_incoming;
  26 local s2s_new_outgoing = require "core.s2smanager".new_outgoing;
  27 local s2s_destroy_session = require "core.s2smanager".destroy_session;
  28 local uuid_gen = require "util.uuid".generate;
  29 local cert_verify_identity = require "util.x509".verify_identity;
  30 local fire_global_event = prosody.events.fire_event;
  31
  32 local s2sout = module:require("s2sout");
  33
  34 local connect_timeout = module:get_option_number("s2s_timeout", 90);
  35 local stream_close_timeout = module:get_option_number("s2s_close_timeout", 5);
  36 local opt_keepalives = module:get_option_boolean("s2s_tcp_keepalives", module:get_option_boolean("tcp_keepalives", true));
  37 local secure_auth = module:get_option_boolean("s2s_secure_auth", false); -- One day...
  38 local secure_domains, insecure_domains =
  39         module:get_option_set("s2s_secure_domains", {})._items, module:get_option_set("s2s_insecure_domains", {})._items;
  40 local require_encryption = module:get_option_boolean("s2s_require_encryption", false);
  41
  42 local sessions = module:shared("sessions");
  43
  44 local log = module._log;
  45
  46 --- Handle stanzas to remote domains
  47
  48 local bouncy_stanzas = { message = true, presence = true, iq = true };
  49 local function bounce_sendq(session, reason)
  50         local sendq = session.sendq;
  51         if not sendq then return; end
  52         session.log("info", "sending error replies for "..#sendq.." queued stanzas because of failed outgoing connection to "..tostring(session.to_host));
  53         local dummy = {
  54                 type = "s2sin";
  55                 send = function(s)
  56                         (session.log or log)("error", "Replying to to an s2s error reply, please report this! Traceback: %s", traceback());
  57                 end;
  58                 dummy = true;
  59         };
  60         for i, data in ipairs(sendq) do
  61                 local reply = data[2];
  62                 if reply and not(reply.attr.xmlns) and bouncy_stanzas[reply.name] then
  63                         reply.attr.type = "error";
  64                         reply:tag("error", {type = "cancel"})
  65                                 :tag("remote-server-not-found", {xmlns = "urn:ietf:params:xml:ns:xmpp-stanzas"}):up();
  66                         if reason then
  67                                 reply:tag("text", {xmlns = "urn:ietf:params:xml:ns:xmpp-stanzas"})
  68                                         :text("Server-to-server connection failed: "..reason):up();
  69                         end
  70                         core_process_stanza(dummy, reply);
  71                 end
  72                 sendq[i] = nil;
  73         end
  74         session.sendq = nil;
  75 end
  76
  77 -- Handles stanzas to existing s2s sessions
  78 function route_to_existing_session(event)
  79         local from_host, to_host, stanza = event.from_host, event.to_host, event.stanza;
  80         if not hosts[from_host] then
  81                 log("warn", "Attempt to send stanza from %s - a host we don't serve", from_host);
  82                 return false;
  83         end
  84         if hosts[to_host] then
  85                 log("warn", "Attempt to route stanza to a remote %s - a host we do serve?!", from_host);
  86                 return false;
  87         end
  88         local host = hosts[from_host].s2sout[to_host];
  89         if host then
  90                 -- We have a connection to this host already
  91                 if host.type == "s2sout_unauthed" and (stanza.name ~= "db:verify" or not host.dialback_key) then
  92                         (host.log or log)("debug", "trying to send over unauthed s2sout to "..to_host);
  93
  94                         -- Queue stanza until we are able to send it
  95                         if host.sendq then t_insert(host.sendq, {tostring(stanza), stanza.attr.type ~= "error" and stanza.attr.type ~= "result" and st.reply(stanza)});
  96                         else host.sendq = { {tostring(stanza), stanza.attr.type ~= "error" and stanza.attr.type ~= "result" and st.reply(stanza)} }; end
  97                         host.log("debug", "stanza [%s] queued ", stanza.name);
  98                         return true;
  99                 elseif host.type == "local" or host.type == "component" then
 100                         log("error", "Trying to send a stanza to ourselves??")
 101                         log("error", "Traceback: %s", traceback());
 102                         log("error", "Stanza: %s", tostring(stanza));
 103                         return false;
 104                 else
 105                         (host.log or log)("debug", "going to send stanza to "..to_host.." from "..from_host);
 106                         -- FIXME
 107                         if host.from_host ~= from_host then
 108                                 log("error", "WARNING! This might, possibly, be a bug, but it might not...");
 109                                 log("error", "We are going to send from %s instead of %s", tostring(host.from_host), tostring(from_host));
 110                         end
 111                         if host.sends2s(stanza) then
 112                                 host.log("debug", "stanza sent over %s", host.type);
 113                                 return true;
 114                         end
 115                 end
 116         end
 117 end
 118
 119 -- Create a new outgoing session for a stanza
 120 function route_to_new_session(event)
 121         local from_host, to_host, stanza = event.from_host, event.to_host, event.stanza;
 122         log("debug", "opening a new outgoing connection for this stanza");
 123         local host_session = s2s_new_outgoing(from_host, to_host);
 124
 125         -- Store in buffer
 126         host_session.bounce_sendq = bounce_sendq;
 127         host_session.sendq = { {tostring(stanza), stanza.attr.type ~= "error" and stanza.attr.type ~= "result" and st.reply(stanza)} };
 128         log("debug", "stanza [%s] queued until connection complete", tostring(stanza.name));
 129         s2sout.initiate_connection(host_session);
 130         if (not host_session.connecting) and (not host_session.conn) then
 131                 log("warn", "Connection to %s failed already, destroying session...", to_host);
 132                 s2s_destroy_session(host_session, "Connection failed");
 133                 return false;
 134         end
 135         return true;
 136 end
 137
 138 local function keepalive(event)
 139         return event.session.sends2s(' ');
 140 end
 141
 142 module:hook("s2s-read-timeout", keepalive, -1);
 143
 144 function module.add_host(module)
 145         if module:get_option_boolean("disallow_s2s", false) then
 146                 module:log("warn", "The 'disallow_s2s' config option is deprecated, please see http://prosody.im/doc/s2s#disabling");
 147                 return nil, "This host has disallow_s2s set";
 148         end
 149         module:hook("route/remote", route_to_existing_session, -1);
 150         module:hook("route/remote", route_to_new_session, -10);
 151         module:hook("s2s-authenticated", make_authenticated, -1);
 152         module:hook("s2s-read-timeout", keepalive, -1);
 153 end
 154
 155 -- Stream is authorised, and ready for normal stanzas
 156 function mark_connected(session)
 157         local sendq, send = session.sendq, session.sends2s;
 158
 159         local from, to = session.from_host, session.to_host;
 160
 161         session.log("info", "%s s2s connection %s->%s complete", session.direction:gsub("^.", string.upper), from, to);
 162
 163         local event_data = { session = session };
 164         if session.type == "s2sout" then
 165                 fire_global_event("s2sout-established", event_data);
 166                 hosts[from].events.fire_event("s2sout-established", event_data);
 167         else
 168                 local host_session = hosts[to];
 169                 session.send = function(stanza)
 170                         return host_session.events.fire_event("route/remote", { from_host = to, to_host = from, stanza = stanza });
 171                 end;
 172
 173                 fire_global_event("s2sin-established", event_data);
 174                 hosts[to].events.fire_event("s2sin-established", event_data);
 175         end
 176
 177         if session.direction == "outgoing" then
 178                 if sendq then
 179                         session.log("debug", "sending %d queued stanzas across new outgoing connection to %s", #sendq, session.to_host);
 180                         for i, data in ipairs(sendq) do
 181                                 send(data[1]);
 182                                 sendq[i] = nil;
 183                         end
 184                         session.sendq = nil;
 185                 end
 186
 187                 session.ip_hosts = nil;
 188                 session.srv_hosts = nil;
 189         end
 190 end
 191
 192 function make_authenticated(event)
 193         local session, host = event.session, event.host;
 194         if not session.secure then
 195                 if require_encryption or (secure_auth and not(insecure_domains[host])) or secure_domains[host] then
 196                         session:close({
 197                                 condition = "policy-violation",
 198                                 text = "Encrypted server-to-server communication is required but was not "
 199                                        ..((session.direction == "outgoing" and "offered") or "used")
 200                         });
 201                 end
 202         end
 203         if hosts[host] then
 204                 session:close({ condition = "undefined-condition", text = "Attempt to authenticate as a host we serve" });
 205         end
 206         if session.type == "s2sout_unauthed" then
 207                 session.type = "s2sout";
 208         elseif session.type == "s2sin_unauthed" then
 209                 session.type = "s2sin";
 210                 if host then
 211                         if not session.hosts[host] then session.hosts[host] = {}; end
 212                         session.hosts[host].authed = true;
 213                 end
 214         elseif session.type == "s2sin" and host then
 215                 if not session.hosts[host] then session.hosts[host] = {}; end
 216                 session.hosts[host].authed = true;
 217         else
 218                 return false;
 219         end
 220         session.log("debug", "connection %s->%s is now authenticated for %s", session.from_host, session.to_host, host);
 221
 222         mark_connected(session);
 223
 224         return true;
 225 end
 226
 227 --- Helper to check that a session peer's certificate is valid
 228 local function check_cert_status(session)
 229         local host = session.direction == "outgoing" and session.to_host or session.from_host
 230         local conn = session.conn:socket()
 231         local cert
 232         if conn.getpeercertificate then
 233                 cert = conn:getpeercertificate()
 234         end
 235
 236         if cert then
 237                 local chain_valid, errors;
 238                 if conn.getpeerverification then
 239                         chain_valid, errors = conn:getpeerverification();
 240                 elseif conn.getpeerchainvalid then -- COMPAT mw/luasec-hg
 241                         chain_valid, errors = conn:getpeerchainvalid();
 242                         errors = (not chain_valid) and { { errors } } or nil;
 243                 else
 244                         chain_valid, errors = false, { { "Chain verification not supported by this version of LuaSec" } };
 245                 end
 246                 -- Is there any interest in printing out all/the number of errors here?
 247                 if not chain_valid then
 248                         (session.log or log)("debug", "certificate chain validation result: invalid");
 249                         for depth, t in pairs(errors or NULL) do
 250                                 (session.log or log)("debug", "certificate error(s) at depth %d: %s", depth-1, table.concat(t, ", "))
 251                         end
 252                         session.cert_chain_status = "invalid";
 253                 else
 254                         (session.log or log)("debug", "certificate chain validation result: valid");
 255                         session.cert_chain_status = "valid";
 256
 257                         -- We'll go ahead and verify the asserted identity if the
 258                         -- connecting server specified one.
 259                         if host then
 260                                 if cert_verify_identity(host, "xmpp-server", cert) then
 261                                         session.cert_identity_status = "valid"
 262                                 else
 263                                         session.cert_identity_status = "invalid"
 264                                 end
 265                                 (session.log or log)("debug", "certificate identity validation result: %s", session.cert_identity_status);
 266                         end
 267                 end
 268         end
 269         return module:fire_event("s2s-check-certificate", { host = host, session = session, cert = cert });
 270 end
 271
 272 --- XMPP stream event handlers
 273
 274 local stream_callbacks = { default_ns = "jabber:server", handlestanza =  core_process_stanza };
 275
 276 local xmlns_xmpp_streams = "urn:ietf:params:xml:ns:xmpp-streams";
 277
 278 function stream_callbacks.streamopened(session, attr)
 279         local send = session.sends2s;
 280
 281         session.version = tonumber(attr.version) or 0;
 282
 283         -- TODO: Rename session.secure to session.encrypted
 284         if session.secure == false then
 285                 session.secure = true;
 286
 287                 local sock = session.conn:socket();
 288                 if sock.info then
 289                         local info = sock:info();
 290                         (session.log or log)("info", "Stream encrypted (%s with %s)", info.protocol, info.cipher);
 291                         session.compressed = info.compression;
 292                 else
 293                         (session.log or log)("info", "Stream encrypted");
 294                         session.compressed = sock.compression and sock:compression(); --COMPAT mw/luasec-hg
 295                 end
 296         end
 297
 298         if session.direction == "incoming" then
 299                 -- Send a reply stream header
 300
 301                 -- Validate to/from
 302                 local to, from = nameprep(attr.to), nameprep(attr.from);
 303                 if not to and attr.to then -- COMPAT: Some servers do not reliably set 'to' (especially on stream restarts)
 304                         session:close({ condition = "improper-addressing", text = "Invalid 'to' address" });
 305                         return;
 306                 end
 307                 if not from and attr.from then -- COMPAT: Some servers do not reliably set 'from' (especially on stream restarts)
 308                         session:close({ condition = "improper-addressing", text = "Invalid 'from' address" });
 309                         return;
 310                 end
 311
 312                 -- Set session.[from/to]_host if they have not been set already and if
 313                 -- this session isn't already authenticated
 314                 if session.type == "s2sin_unauthed" and from and not session.from_host then
 315                         session.from_host = from;
 316                 elseif from ~= session.from_host then
 317                         session:close({ condition = "improper-addressing", text = "New stream 'from' attribute does not match original" });
 318                         return;
 319                 end
 320                 if session.type == "s2sin_unauthed" and to and not session.to_host then
 321                         session.to_host = to;
 322                 elseif to ~= session.to_host then
 323                         session:close({ condition = "improper-addressing", text = "New stream 'to' attribute does not match original" });
 324                         return;
 325                 end
 326
 327                 -- For convenience we'll put the sanitised values into these variables
 328                 to, from = session.to_host, session.from_host;
 329
 330                 session.streamid = uuid_gen();
 331                 (session.log or log)("debug", "Incoming s2s received %s", st.stanza("stream:stream", attr):top_tag());
 332                 if to then
 333                         if not hosts[to] then
 334                                 -- Attempting to connect to a host we don't serve
 335                                 session:close({
 336                                         condition = "host-unknown";
 337                                         text = "This host does not serve "..to
 338                                 });
 339                                 return;
 340                         elseif not hosts[to].modules.s2s then
 341                                 -- Attempting to connect to a host that disallows s2s
 342                                 session:close({
 343                                         condition = "policy-violation";
 344                                         text = "Server-to-server communication is disabled for this host";
 345                                 });
 346                                 return;
 347                         end
 348                 end
 349
 350                 if hosts[from] then
 351                         session:close({ condition = "undefined-condition", text = "Attempt to connect from a host we serve" });
 352                         return;
 353                 end
 354
 355                 if session.secure and not session.cert_chain_status then
 356                         if check_cert_status(session) == false then
 357                                 return;
 358                         end
 359                 end
 360
 361                 session:open_stream(session.to_host, session.from_host)
 362                 if session.version >= 1.0 then
 363                         local features = st.stanza("stream:features");
 364
 365                         if to then
 366                                 hosts[to].events.fire_event("s2s-stream-features", { origin = session, features = features });
 367                         else
 368                                 (session.log or log)("warn", "No 'to' on stream header from %s means we can't offer any features", from or "unknown host");
 369                         end
 370
 371                         log("debug", "Sending stream features: %s", tostring(features));
 372                         send(features);
 373                 end
 374         elseif session.direction == "outgoing" then
 375                 -- If we are just using the connection for verifying dialback keys, we won't try and auth it
 376                 if not attr.id then error("stream response did not give us a streamid!!!"); end
 377                 session.streamid = attr.id;
 378
 379                 if session.secure and not session.cert_chain_status then
 380                         if check_cert_status(session) == false then
 381                                 return;
 382                         end
 383                 end
 384
 385                 -- Send unauthed buffer
 386                 -- (stanzas which are fine to send before dialback)
 387                 -- Note that this is *not* the stanza queue (which
 388                 -- we can only send if auth succeeds) :)
 389                 local send_buffer = session.send_buffer;
 390                 if send_buffer and #send_buffer > 0 then
 391                         log("debug", "Sending s2s send_buffer now...");
 392                         for i, data in ipairs(send_buffer) do
 393                                 session.sends2s(tostring(data));
 394                                 send_buffer[i] = nil;
 395                         end
 396                 end
 397                 session.send_buffer = nil;
 398
 399                 -- If server is pre-1.0, don't wait for features, just do dialback
 400                 if session.version < 1.0 then
 401                         if not session.dialback_verifying then
 402                                 hosts[session.from_host].events.fire_event("s2sout-authenticate-legacy", { origin = session });
 403                         else
 404                                 mark_connected(session);
 405                         end
 406                 end
 407         end
 408         session.notopen = nil;
 409 end
 410
 411 function stream_callbacks.streamclosed(session)
 412         (session.log or log)("debug", "Received </stream:stream>");
 413         session:close(false);
 414 end
 415
 416 function stream_callbacks.error(session, error, data)
 417         if error == "no-stream" then
 418                 session:close("invalid-namespace");
 419         elseif error == "parse-error" then
 420                 session.log("debug", "Server-to-server XML parse error: %s", tostring(error));
 421                 session:close("not-well-formed");
 422         elseif error == "stream-error" then
 423                 local condition, text = "undefined-condition";
 424                 for child in data:children() do
 425                         if child.attr.xmlns == xmlns_xmpp_streams then
 426                                 if child.name ~= "text" then
 427                                         condition = child.name;
 428                                 else
 429                                         text = child:get_text();
 430                                 end
 431                                 if condition ~= "undefined-condition" and text then
 432                                         break;
 433                                 end
 434                         end
 435                 end
 436                 text = condition .. (text and (" ("..text..")") or "");
 437                 session.log("info", "Session closed by remote with error: %s", text);
 438                 session:close(nil, text);
 439         end
 440 end
 441
 442 local function handleerr(err) log("error", "Traceback[s2s]: %s", traceback(tostring(err), 2)); end
 443 function stream_callbacks.handlestanza(session, stanza)
 444         if stanza.attr.xmlns == "jabber:client" then --COMPAT: Prosody pre-0.6.2 may send jabber:client
 445                 stanza.attr.xmlns = nil;
 446         end
 447         stanza = session.filter("stanzas/in", stanza);
 448         if stanza then
 449                 return xpcall(function () return core_process_stanza(session, stanza) end, handleerr);
 450         end
 451 end
 452
 453 local listener = {};
 454
 455 --- Session methods
 456 local stream_xmlns_attr = {xmlns='urn:ietf:params:xml:ns:xmpp-streams'};
 457 local function session_close(session, reason, remote_reason)
 458         local log = session.log or log;
 459         if session.conn then
 460                 if session.notopen then
 461                         if session.direction == "incoming" then
 462                                 session:open_stream(session.to_host, session.from_host);
 463                         else
 464                                 session:open_stream(session.from_host, session.to_host);
 465                         end
 466                 end
 467                 if reason then -- nil == no err, initiated by us, false == initiated by remote
 468                         if type(reason) == "string" then -- assume stream error
 469                                 log("debug", "Disconnecting %s[%s], <stream:error> is: %s", session.host or "(unknown host)", session.type, reason);
 470                                 session.sends2s(st.stanza("stream:error"):tag(reason, {xmlns = 'urn:ietf:params:xml:ns:xmpp-streams' }));
 471                         elseif type(reason) == "table" then
 472                                 if reason.condition then
 473                                         local stanza = st.stanza("stream:error"):tag(reason.condition, stream_xmlns_attr):up();
 474                                         if reason.text then
 475                                                 stanza:tag("text", stream_xmlns_attr):text(reason.text):up();
 476                                         end
 477                                         if reason.extra then
 478                                                 stanza:add_child(reason.extra);
 479                                         end
 480                                         log("debug", "Disconnecting %s[%s], <stream:error> is: %s", session.host or "(unknown host)", session.type, tostring(stanza));
 481                                         session.sends2s(stanza);
 482                                 elseif reason.name then -- a stanza
 483                                         log("debug", "Disconnecting %s->%s[%s], <stream:error> is: %s", session.from_host or "(unknown host)", session.to_host or "(unknown host)", session.type, tostring(reason));
 484                                         session.sends2s(reason);
 485                                 end
 486                         end
 487                 end
 488
 489                 session.sends2s("</stream:stream>");
 490                 function session.sends2s() return false; end
 491
 492                 local reason = remote_reason or (reason and (reason.text or reason.condition)) or reason;
 493                 session.log("info", "%s s2s stream %s->%s closed: %s", session.direction:gsub("^.", string.upper), session.from_host or "(unknown host)", session.to_host or "(unknown host)", reason or "stream closed");
 494
 495                 -- Authenticated incoming stream may still be sending us stanzas, so wait for </stream:stream> from remote
 496                 local conn = session.conn;
 497                 if reason == nil and not session.notopen and session.type == "s2sin" then
 498                         add_task(stream_close_timeout, function ()
 499                                 if not session.destroyed then
 500                                         session.log("warn", "Failed to receive a stream close response, closing connection anyway...");
 501                                         s2s_destroy_session(session, reason);
 502                                         conn:close();
 503                                 end
 504                         end);
 505                 else
 506                         s2s_destroy_session(session, reason);
 507                         conn:close(); -- Close immediately, as this is an outgoing connection or is not authed
 508                 end
 509         end
 510 end
 511
 512 function session_open_stream(session, from, to)
 513         local attr = {
 514                 ["xmlns:stream"] = 'http://etherx.jabber.org/streams',
 515                 xmlns = 'jabber:server',
 516                 version = session.version and (session.version > 0 and "1.0" or nil),
 517                 ["xml:lang"] = 'en',
 518                 id = session.streamid,
 519                 from = from, to = to,
 520         }
 521         if not from or (hosts[from] and hosts[from].modules.dialback) then
 522                 attr["xmlns:db"] = 'jabber:server:dialback';
 523         end
 524
 525         session.sends2s("<?xml version='1.0'?>");
 526         session.sends2s(st.stanza("stream:stream", attr):top_tag());
 527         return true;
 528 end
 529
 530 -- Session initialization logic shared by incoming and outgoing
 531 local function initialize_session(session)
 532         local stream = new_xmpp_stream(session, stream_callbacks);
 533         session.stream = stream;
 534
 535         session.notopen = true;
 536
 537         function session.reset_stream()
 538                 session.notopen = true;
 539                 session.stream:reset();
 540         end
 541
 542         session.open_stream = session_open_stream;
 543
 544         local filter = session.filter;
 545         function session.data(data)
 546                 data = filter("bytes/in", data);
 547                 if data then
 548                         local ok, err = stream:feed(data);
 549                         if ok then return; end
 550                         (session.log or log)("warn", "Received invalid XML: %s", data);
 551                         (session.log or log)("warn", "Problem was: %s", err);
 552                         session:close("not-well-formed");
 553                 end
 554         end
 555
 556         session.close = session_close;
 557
 558         local handlestanza = stream_callbacks.handlestanza;
 559         function session.dispatch_stanza(session, stanza)
 560                 return handlestanza(session, stanza);
 561         end
 562
 563         add_task(connect_timeout, function ()
 564                 if session.type == "s2sin" or session.type == "s2sout" then
 565                         return; -- Ok, we're connected
 566                 elseif session.type == "s2s_destroyed" then
 567                         return; -- Session already destroyed
 568                 end
 569                 -- Not connected, need to close session and clean up
 570                 (session.log or log)("debug", "Destroying incomplete session %s->%s due to inactivity",
 571                 session.from_host or "(unknown)", session.to_host or "(unknown)");
 572                 session:close("connection-timeout");
 573         end);
 574 end
 575
 576 function listener.onconnect(conn)
 577         conn:setoption("keepalive", opt_keepalives);
 578         local session = sessions[conn];
 579         if not session then -- New incoming connection
 580                 session = s2s_new_incoming(conn);
 581                 sessions[conn] = session;
 582                 session.log("debug", "Incoming s2s connection");
 583
 584                 local filter = initialize_filters(session);
 585                 local w = conn.write;
 586                 session.sends2s = function (t)
 587                         log("debug", "sending: %s", t.top_tag and t:top_tag() or t:match("^([^>]*>?)"));
 588                         if t.name then
 589                                 t = filter("stanzas/out", t);
 590                         end
 591                         if t then
 592                                 t = filter("bytes/out", tostring(t));
 593                                 if t then
 594                                         return w(conn, t);
 595                                 end
 596                         end
 597                 end
 598
 599                 initialize_session(session);
 600         else -- Outgoing session connected
 601                 session:open_stream(session.from_host, session.to_host);
 602         end
 603         session.ip = conn:ip();
 604 end
 605
 606 function listener.onincoming(conn, data)
 607         local session = sessions[conn];
 608         if session then
 609                 session.data(data);
 610         end
 611 end
 612
 613 function listener.onstatus(conn, status)
 614         if status == "ssl-handshake-complete" then
 615                 local session = sessions[conn];
 616                 if session and session.direction == "outgoing" then
 617                         session.log("debug", "Sending stream header...");
 618                         session:open_stream(session.from_host, session.to_host);
 619                 end
 620         end
 621 end
 622
 623 function listener.ondisconnect(conn, err)
 624         local session = sessions[conn];
 625         if session then
 626                 sessions[conn] = nil;
 627                 if err and session.direction == "outgoing" and session.notopen then
 628                         (session.log or log)("debug", "s2s connection attempt failed: %s", err);
 629                         if s2sout.attempt_connection(session, err) then
 630                                 return; -- Session lives for now
 631                         end
 632                 end
 633                 (session.log or log)("debug", "s2s disconnected: %s->%s (%s)", tostring(session.from_host), tostring(session.to_host), tostring(err or "connection closed"));
 634                 s2s_destroy_session(session, err);
 635         end
 636 end
 637
 638 function listener.onreadtimeout(conn)
 639         local session = sessions[conn];
 640         if session then
 641                 return (hosts[session.host] or prosody).events.fire_event("s2s-read-timeout", { session = session });
 642         end
 643 end
 644
 645 function listener.register_outgoing(conn, session)
 646         session.direction = "outgoing";
 647         sessions[conn] = session;
 648         initialize_session(session);
 649 end
 650
 651 function check_auth_policy(event)
 652         local host, session = event.host, event.session;
 653         local must_secure = secure_auth;
 654
 655         if not must_secure and secure_domains[host] then
 656                 must_secure = true;
 657         elseif must_secure and insecure_domains[host] then
 658                 must_secure = false;
 659         end
 660
 661         if must_secure and (session.cert_chain_status ~= "valid" or session.cert_identity_status ~= "valid") then
 662                 module:log("warn", "Forbidding insecure connection to/from %s", host);
 663                 if session.direction == "incoming" then
 664                         session:close({ condition = "not-authorized", text = "Your server's certificate is invalid, expired, or not trusted by "..session.to_host });
 665                 else -- Close outgoing connections without warning
 666                         session:close(false);
 667                 end
 668                 return false;
 669         end
 670 end
 671
 672 module:hook("s2s-check-certificate", check_auth_policy, -1);
 673
 674 s2sout.set_listener(listener);
 675
 676 module:hook("server-stopping", function(event)
 677         local reason = event.reason;
 678         for _, session in pairs(sessions) do
 679                 session:close{ condition = "system-shutdown", text = reason };
 680         end
 681 end,500);
 682
 683
 684
 685 module:provides("net", {
 686         name = "s2s";
 687         listener = listener;
 688         default_port = 5269;
 689         encryption = "starttls";
 690         multiplex = {
 691                 pattern = "^<.*:stream.*%sxmlns%s*=%s*(['\"])jabber:server%1.*>";
 692         };
 693 });
 694