2 -- Copyright (C) 2008-2010 Matthew Wild
3 -- Copyright (C) 2008-2010 Waqas Hussain
5 -- This project is MIT/X11 licensed. Please see the
6 -- COPYING file in the source package for more information.
11 local prosody = prosody;
12 local hosts = prosody.hosts;
13 local core_process_stanza = prosody.core_process_stanza;
15 local tostring, type = tostring, type;
16 local t_insert = table.insert;
17 local xpcall, traceback = xpcall, debug.traceback;
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;
32 local s2sout = module:require("s2sout");
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);
42 local sessions = module:shared("sessions");
44 local log = module._log;
46 --- Handle stanzas to remote domains
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));
56 (session.log or log)("error", "Replying to to an s2s error reply, please report this! Traceback: %s", traceback());
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();
67 reply:tag("text", {xmlns = "urn:ietf:params:xml:ns:xmpp-stanzas"})
68 :text("Server-to-server connection failed: "..reason):up();
70 core_process_stanza(dummy, reply);
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);
84 if hosts[to_host] then
85 log("warn", "Attempt to route stanza to a remote %s - a host we do serve?!", from_host);
88 local host = hosts[from_host].s2sout[to_host];
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);
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);
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));
105 (host.log or log)("debug", "going to send stanza to "..to_host.." from "..from_host);
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));
111 if host.sends2s(stanza) then
112 host.log("debug", "stanza sent over %s", host.type);
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);
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");
138 function module.add_host(module)
139 if module:get_option_boolean("disallow_s2s", false) then
140 module:log("warn", "The 'disallow_s2s' config option is deprecated, please see http://prosody.im/doc/s2s#disabling");
141 return nil, "This host has disallow_s2s set";
143 module:hook("route/remote", route_to_existing_session, -1);
144 module:hook("route/remote", route_to_new_session, -10);
145 module:hook("s2s-authenticated", make_authenticated, -1);
148 -- Stream is authorised, and ready for normal stanzas
149 function mark_connected(session)
150 local sendq, send = session.sendq, session.sends2s;
152 local from, to = session.from_host, session.to_host;
154 session.log("info", "%s s2s connection %s->%s complete", session.direction, from, to);
156 local event_data = { session = session };
157 if session.type == "s2sout" then
158 fire_global_event("s2sout-established", event_data);
159 hosts[from].events.fire_event("s2sout-established", event_data);
161 local host_session = hosts[to];
162 session.send = function(stanza)
163 return host_session.events.fire_event("route/remote", { from_host = to, to_host = from, stanza = stanza });
166 fire_global_event("s2sin-established", event_data);
167 hosts[to].events.fire_event("s2sin-established", event_data);
170 if session.direction == "outgoing" then
172 session.log("debug", "sending %d queued stanzas across new outgoing connection to %s", #sendq, session.to_host);
173 for i, data in ipairs(sendq) do
180 session.ip_hosts = nil;
181 session.srv_hosts = nil;
185 function make_authenticated(event)
186 local session, host = event.session, event.host;
187 if not session.secure then
188 if require_encryption or (secure_auth and not(insecure_domains[host])) or secure_domains[host] then
190 condition = "policy-violation",
191 text = "Encrypted server-to-server communication is required but was not "
192 ..((session.direction == "outgoing" and "offered") or "used")
197 session:close({ condition = "undefined-condition", text = "Attempt to authenticate as a host we serve" });
199 if session.type == "s2sout_unauthed" then
200 session.type = "s2sout";
201 elseif session.type == "s2sin_unauthed" then
202 session.type = "s2sin";
204 if not session.hosts[host] then session.hosts[host] = {}; end
205 session.hosts[host].authed = true;
207 elseif session.type == "s2sin" and host then
208 if not session.hosts[host] then session.hosts[host] = {}; end
209 session.hosts[host].authed = true;
213 session.log("debug", "connection %s->%s is now authenticated for %s", session.from_host, session.to_host, host);
215 mark_connected(session);
220 --- Helper to check that a session peer's certificate is valid
221 local function check_cert_status(session)
222 local host = session.direction == "outgoing" and session.to_host or session.from_host
223 local conn = session.conn:socket()
225 if conn.getpeercertificate then
226 cert = conn:getpeercertificate()
230 local chain_valid, errors;
231 if conn.getpeerverification then
232 chain_valid, errors = conn:getpeerverification();
233 elseif conn.getpeerchainvalid then -- COMPAT mw/luasec-hg
234 chain_valid, errors = conn:getpeerchainvalid();
235 errors = (not chain_valid) and { { errors } } or nil;
237 chain_valid, errors = false, { { "Chain verification not supported by this version of LuaSec" } };
239 -- Is there any interest in printing out all/the number of errors here?
240 if not chain_valid then
241 (session.log or log)("debug", "certificate chain validation result: invalid");
242 for depth, t in ipairs(errors or NULL) do
243 (session.log or log)("debug", "certificate error(s) at depth %d: %s", depth-1, table.concat(t, ", "))
245 session.cert_chain_status = "invalid";
247 (session.log or log)("debug", "certificate chain validation result: valid");
248 session.cert_chain_status = "valid";
250 -- We'll go ahead and verify the asserted identity if the
251 -- connecting server specified one.
253 if cert_verify_identity(host, "xmpp-server", cert) then
254 session.cert_identity_status = "valid"
256 session.cert_identity_status = "invalid"
261 return module:fire_event("s2s-check-certificate", { host = host, session = session, cert = cert });
264 --- XMPP stream event handlers
266 local stream_callbacks = { default_ns = "jabber:server", handlestanza = core_process_stanza };
268 local xmlns_xmpp_streams = "urn:ietf:params:xml:ns:xmpp-streams";
270 function stream_callbacks.streamopened(session, attr)
271 local send = session.sends2s;
273 session.version = tonumber(attr.version) or 0;
275 -- TODO: Rename session.secure to session.encrypted
276 if session.secure == false then
277 session.secure = true;
279 -- Check if TLS compression is used
280 local sock = session.conn:socket();
282 session.compressed = sock:info"compression";
283 elseif sock.compression then
284 session.compressed = sock:compression(); --COMPAT mw/luasec-hg
288 if session.direction == "incoming" then
289 -- Send a reply stream header
292 local to, from = nameprep(attr.to), nameprep(attr.from);
293 if not to and attr.to then -- COMPAT: Some servers do not reliably set 'to' (especially on stream restarts)
294 session:close({ condition = "improper-addressing", text = "Invalid 'to' address" });
297 if not from and attr.from then -- COMPAT: Some servers do not reliably set 'from' (especially on stream restarts)
298 session:close({ condition = "improper-addressing", text = "Invalid 'from' address" });
302 -- Set session.[from/to]_host if they have not been set already and if
303 -- this session isn't already authenticated
304 if session.type == "s2sin_unauthed" and from and not session.from_host then
305 session.from_host = from;
306 elseif from ~= session.from_host then
307 session:close({ condition = "improper-addressing", text = "New stream 'from' attribute does not match original" });
310 if session.type == "s2sin_unauthed" and to and not session.to_host then
311 session.to_host = to;
312 elseif to ~= session.to_host then
313 session:close({ condition = "improper-addressing", text = "New stream 'to' attribute does not match original" });
317 -- For convenience we'll put the sanitised values into these variables
318 to, from = session.to_host, session.from_host;
320 session.streamid = uuid_gen();
321 (session.log or log)("debug", "Incoming s2s received %s", st.stanza("stream:stream", attr):top_tag());
323 if not hosts[to] then
324 -- Attempting to connect to a host we don't serve
326 condition = "host-unknown";
327 text = "This host does not serve "..to
330 elseif not hosts[to].modules.s2s then
331 -- Attempting to connect to a host that disallows s2s
333 condition = "policy-violation";
334 text = "Server-to-server communication is disabled for this host";
341 session:close({ condition = "undefined-condition", text = "Attempt to connect from a host we serve" });
345 if session.secure and not session.cert_chain_status then
346 if check_cert_status(session) == false then
351 session:open_stream(session.to_host, session.from_host)
352 if session.version >= 1.0 then
353 local features = st.stanza("stream:features");
356 hosts[to].events.fire_event("s2s-stream-features", { origin = session, features = features });
358 (session.log or log)("warn", "No 'to' on stream header from %s means we can't offer any features", from or "unknown host");
361 log("debug", "Sending stream features: %s", tostring(features));
364 elseif session.direction == "outgoing" then
365 -- If we are just using the connection for verifying dialback keys, we won't try and auth it
366 if not attr.id then error("stream response did not give us a streamid!!!"); end
367 session.streamid = attr.id;
369 if session.secure and not session.cert_chain_status then
370 if check_cert_status(session) == false then
375 -- Send unauthed buffer
376 -- (stanzas which are fine to send before dialback)
377 -- Note that this is *not* the stanza queue (which
378 -- we can only send if auth succeeds) :)
379 local send_buffer = session.send_buffer;
380 if send_buffer and #send_buffer > 0 then
381 log("debug", "Sending s2s send_buffer now...");
382 for i, data in ipairs(send_buffer) do
383 session.sends2s(tostring(data));
384 send_buffer[i] = nil;
387 session.send_buffer = nil;
389 -- If server is pre-1.0, don't wait for features, just do dialback
390 if session.version < 1.0 then
391 if not session.dialback_verifying then
392 hosts[session.from_host].events.fire_event("s2sout-authenticate-legacy", { origin = session });
394 mark_connected(session);
398 session.notopen = nil;
401 function stream_callbacks.streamclosed(session)
402 (session.log or log)("debug", "Received </stream:stream>");
403 session:close(false);
406 function stream_callbacks.error(session, error, data)
407 if error == "no-stream" then
408 session:close("invalid-namespace");
409 elseif error == "parse-error" then
410 session.log("debug", "Server-to-server XML parse error: %s", tostring(error));
411 session:close("not-well-formed");
412 elseif error == "stream-error" then
413 local condition, text = "undefined-condition";
414 for child in data:children() do
415 if child.attr.xmlns == xmlns_xmpp_streams then
416 if child.name ~= "text" then
417 condition = child.name;
419 text = child:get_text();
421 if condition ~= "undefined-condition" and text then
426 text = condition .. (text and (" ("..text..")") or "");
427 session.log("info", "Session closed by remote with error: %s", text);
428 session:close(nil, text);
432 local function handleerr(err) log("error", "Traceback[s2s]: %s", traceback(tostring(err), 2)); end
433 function stream_callbacks.handlestanza(session, stanza)
434 if stanza.attr.xmlns == "jabber:client" then --COMPAT: Prosody pre-0.6.2 may send jabber:client
435 stanza.attr.xmlns = nil;
437 stanza = session.filter("stanzas/in", stanza);
439 return xpcall(function () return core_process_stanza(session, stanza) end, handleerr);
446 local stream_xmlns_attr = {xmlns='urn:ietf:params:xml:ns:xmpp-streams'};
447 local function session_close(session, reason, remote_reason)
448 local log = session.log or log;
450 if session.notopen then
451 if session.direction == "incoming" then
452 session:open_stream(session.to_host, session.from_host);
454 session:open_stream(session.from_host, session.to_host);
457 if reason then -- nil == no err, initiated by us, false == initiated by remote
458 if type(reason) == "string" then -- assume stream error
459 log("debug", "Disconnecting %s[%s], <stream:error> is: %s", session.host or "(unknown host)", session.type, reason);
460 session.sends2s(st.stanza("stream:error"):tag(reason, {xmlns = 'urn:ietf:params:xml:ns:xmpp-streams' }));
461 elseif type(reason) == "table" then
462 if reason.condition then
463 local stanza = st.stanza("stream:error"):tag(reason.condition, stream_xmlns_attr):up();
465 stanza:tag("text", stream_xmlns_attr):text(reason.text):up();
468 stanza:add_child(reason.extra);
470 log("debug", "Disconnecting %s[%s], <stream:error> is: %s", session.host or "(unknown host)", session.type, tostring(stanza));
471 session.sends2s(stanza);
472 elseif reason.name then -- a stanza
473 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));
474 session.sends2s(reason);
479 session.sends2s("</stream:stream>");
480 function session.sends2s() return false; end
482 local reason = remote_reason or (reason and (reason.text or reason.condition)) or reason;
483 session.log("info", "%s s2s stream %s->%s closed: %s", session.direction, session.from_host or "(unknown host)", session.to_host or "(unknown host)", reason or "stream closed");
485 -- Authenticated incoming stream may still be sending us stanzas, so wait for </stream:stream> from remote
486 local conn = session.conn;
487 if reason == nil and not session.notopen and session.type == "s2sin" then
488 add_task(stream_close_timeout, function ()
489 if not session.destroyed then
490 session.log("warn", "Failed to receive a stream close response, closing connection anyway...");
491 s2s_destroy_session(session, reason);
496 s2s_destroy_session(session, reason);
497 conn:close(); -- Close immediately, as this is an outgoing connection or is not authed
502 function session_open_stream(session, from, to)
504 ["xmlns:stream"] = 'http://etherx.jabber.org/streams',
505 xmlns = 'jabber:server',
506 version = session.version and (session.version > 0 and "1.0" or nil),
508 id = session.streamid,
509 from = from, to = to,
511 if not from or (hosts[from] and hosts[from].modules.dialback) then
512 attr["xmlns:db"] = 'jabber:server:dialback';
515 session.sends2s("<?xml version='1.0'?>");
516 session.sends2s(st.stanza("stream:stream", attr):top_tag());
520 -- Session initialization logic shared by incoming and outgoing
521 local function initialize_session(session)
522 local stream = new_xmpp_stream(session, stream_callbacks);
523 session.stream = stream;
525 session.notopen = true;
527 function session.reset_stream()
528 session.notopen = true;
529 session.stream:reset();
532 session.open_stream = session_open_stream;
534 local filter = session.filter;
535 function session.data(data)
536 data = filter("bytes/in", data);
538 local ok, err = stream:feed(data);
539 if ok then return; end
540 (session.log or log)("warn", "Received invalid XML: %s", data);
541 (session.log or log)("warn", "Problem was: %s", err);
542 session:close("not-well-formed");
546 session.close = session_close;
548 local handlestanza = stream_callbacks.handlestanza;
549 function session.dispatch_stanza(session, stanza)
550 return handlestanza(session, stanza);
553 add_task(connect_timeout, function ()
554 if session.type == "s2sin" or session.type == "s2sout" then
555 return; -- Ok, we're connected
556 elseif session.type == "s2s_destroyed" then
557 return; -- Session already destroyed
559 -- Not connected, need to close session and clean up
560 (session.log or log)("debug", "Destroying incomplete session %s->%s due to inactivity",
561 session.from_host or "(unknown)", session.to_host or "(unknown)");
562 session:close("connection-timeout");
566 function listener.onconnect(conn)
567 conn:setoption("keepalive", opt_keepalives);
568 local session = sessions[conn];
569 if not session then -- New incoming connection
570 session = s2s_new_incoming(conn);
571 sessions[conn] = session;
572 session.log("debug", "Incoming s2s connection");
574 local filter = initialize_filters(session);
575 local w = conn.write;
576 session.sends2s = function (t)
577 log("debug", "sending: %s", t.top_tag and t:top_tag() or t:match("^([^>]*>?)"));
579 t = filter("stanzas/out", t);
582 t = filter("bytes/out", tostring(t));
589 initialize_session(session);
590 else -- Outgoing session connected
591 session:open_stream(session.from_host, session.to_host);
595 function listener.onincoming(conn, data)
596 local session = sessions[conn];
602 function listener.onstatus(conn, status)
603 if status == "ssl-handshake-complete" then
604 local session = sessions[conn];
605 if session and session.direction == "outgoing" then
606 session.log("debug", "Sending stream header...");
607 session:open_stream(session.from_host, session.to_host);
612 function listener.ondisconnect(conn, err)
613 local session = sessions[conn];
615 sessions[conn] = nil;
616 if err and session.direction == "outgoing" and session.notopen then
617 (session.log or log)("debug", "s2s connection attempt failed: %s", err);
618 if s2sout.attempt_connection(session, err) then
619 return; -- Session lives for now
622 (session.log or log)("debug", "s2s disconnected: %s->%s (%s)", tostring(session.from_host), tostring(session.to_host), tostring(err or "connection closed"));
623 s2s_destroy_session(session, err);
627 function listener.register_outgoing(conn, session)
628 session.direction = "outgoing";
629 sessions[conn] = session;
630 initialize_session(session);
633 function check_auth_policy(event)
634 local host, session = event.host, event.session;
635 local must_secure = secure_auth;
637 if not must_secure and secure_domains[host] then
639 elseif must_secure and insecure_domains[host] then
643 if must_secure and not session.cert_identity_status then
644 module:log("warn", "Forbidding insecure connection to/from %s", host);
645 if session.direction == "incoming" then
646 session:close({ condition = "not-authorized", text = "Your server's certificate is invalid, expired, or not trusted by "..session.to_host });
647 else -- Close outgoing connections without warning
648 session:close(false);
654 module:hook("s2s-check-certificate", check_auth_policy, -1);
656 s2sout.set_listener(listener);
658 module:hook("server-stopping", function(event)
659 local reason = event.reason;
660 for _, session in pairs(sessions) do
661 session:close{ condition = "system-shutdown", text = reason };
667 module:provides("net", {
671 encryption = "starttls";
673 pattern = "^<.*:stream.*%sxmlns%s*=%s*(['\"])jabber:server%1.*>";