s2smanager: Don't bounce error replies for error and result stanzas.
[prosody.git] / core / s2smanager.lua
index 42aa1016b13b50abadfe7a157c26639f30298832..1d038433b874fefdb3d976374387bfe780eed663 100644 (file)
@@ -1,6 +1,6 @@
 -- Prosody IM
--- Copyright (C) 2008-2009 Matthew Wild
--- Copyright (C) 2008-2009 Waqas Hussain
+-- Copyright (C) 2008-2010 Matthew Wild
+-- Copyright (C) 2008-2010 Waqas Hussain
 -- 
 -- This project is MIT/X11 licensed. Please see the
 -- COPYING file in the source package for more information.
@@ -16,18 +16,19 @@ local socket = require "socket";
 local format = string.format;
 local t_insert, t_sort = table.insert, table.sort;
 local get_traceback = debug.traceback;
-local tostring, pairs, ipairs, getmetatable, newproxy, error, tonumber
-    = tostring, pairs, ipairs, getmetatable, newproxy, error, tonumber;
+local tostring, pairs, ipairs, getmetatable, newproxy, error, tonumber, setmetatable
+    = tostring, pairs, ipairs, getmetatable, newproxy, error, tonumber, setmetatable;
 
 local idna_to_ascii = require "util.encodings".idna.to_ascii;
 local connlisteners_get = require "net.connlisteners".get;
+local initialize_filters = require "util.filters".initialize;
 local wrapclient = require "net.server".wrapclient;
 local modulemanager = require "core.modulemanager";
 local st = require "stanza";
 local stanza = st.stanza;
 local nameprep = require "util.encodings".stringprep.nameprep;
 
-local fire_event = require "core.eventmanager".fire_event;
+local fire_event = prosody.events.fire_event;
 local uuid_gen = require "util.uuid".generate;
 
 local logger_init = require "util.logger".init;
@@ -39,17 +40,23 @@ local sha256_hash = require "util.hashes".sha256;
 local adns, dns = require "net.adns", require "net.dns";
 local config = require "core.configmanager";
 local connect_timeout = config.get("*", "core", "s2s_timeout") or 60;
-local dns_timeout = config.get("*", "core", "dns_timeout") or 60;
+local dns_timeout = config.get("*", "core", "dns_timeout") or 15;
 local max_dns_depth = config.get("*", "core", "dns_max_depth") or 3;
 
+dns.settimeout(dns_timeout);
+
+local prosody = _G.prosody;
 incoming_s2s = {};
-_G.prosody.incoming_s2s = incoming_s2s;
+prosody.incoming_s2s = incoming_s2s;
 local incoming_s2s = incoming_s2s;
 
 module "s2smanager"
 
-local function compare_srv_priorities(a,b) return a.priority < b.priority or a.weight < b.weight; end
+function compare_srv_priorities(a,b)
+       return a.priority < b.priority or (a.priority == b.priority and a.weight > b.weight);
+end
 
+local bouncy_stanzas = { message = true, presence = true, iq = true };
 local function bounce_sendq(session, reason)
        local sendq = session.sendq;
        if sendq then
@@ -63,8 +70,7 @@ local function bounce_sendq(session, reason)
                };
                for i, data in ipairs(sendq) do
                        local reply = data[2];
-                       local xmlns = reply.attr.xmlns;
-                       if not xmlns or xmlns == "jabber:client" or xmlns == "jabber:server" then
+                       if reply and not(reply.attr.xmlns) and bouncy_stanzas[reply.name] then
                                reply.attr.type = "error";
                                reply:tag("error", {type = "cancel"})
                                        :tag("remote-server-not-found", {xmlns = "urn:ietf:params:xml:ns:xmpp-stanzas"}):up();
@@ -87,17 +93,18 @@ function send_to_host(from_host, to_host, data)
        local host = hosts[from_host].s2sout[to_host];
        if host then
                -- We have a connection to this host already
-               if host.type == "s2sout_unauthed" and (data.name ~= "db:verify" or not host.dialback_key) and ((not data.xmlns) or data.xmlns == "jabber:client" or data.xmlns == "jabber:server") then
+               if host.type == "s2sout_unauthed" and (data.name ~= "db:verify" or not host.dialback_key) then
                        (host.log or log)("debug", "trying to send over unauthed s2sout to "..to_host);
                        
                        -- Queue stanza until we are able to send it
-                       if host.sendq then t_insert(host.sendq, {tostring(data), st.reply(data)});
-                       else host.sendq = { {tostring(data), st.reply(data)} }; end
+                       if host.sendq then t_insert(host.sendq, {tostring(data), data.attr.type ~= "error" and data.attr.type ~= "result" and st.reply(data)});
+                       else host.sendq = { {tostring(data), data.attr.type ~= "error" and data.attr.type ~= "result" and st.reply(data)} }; end
                        host.log("debug", "stanza [%s] queued ", data.name);
                elseif host.type == "local" or host.type == "component" then
                        log("error", "Trying to send a stanza to ourselves??")
                        log("error", "Traceback: %s", get_traceback());
                        log("error", "Stanza: %s", tostring(data));
+                       return false;
                else
                        (host.log or log)("debug", "going to send stanza to "..to_host.." from "..from_host);
                        -- FIXME
@@ -113,13 +120,18 @@ function send_to_host(from_host, to_host, data)
                local host_session = new_outgoing(from_host, to_host);
 
                -- Store in buffer
-               host_session.sendq = { {tostring(data), st.reply(data)} };
+               host_session.sendq = { {tostring(data), data.attr.type ~= "error" and data.attr.type ~= "result" and st.reply(data)} };
                log("debug", "stanza [%s] queued until connection complete", tostring(data.name));
                if (not host_session.connecting) and (not host_session.conn) then
                        log("warn", "Connection to %s failed already, destroying session...", to_host);
-                       destroy_session(host_session);
+                       if not destroy_session(host_session, "Connection failed") then
+                               -- Already destroyed, we need to bounce our stanza
+                               bounce_sendq(host_session, host_session.destruction_reason);
+                       end
+                       return false;
                end
        end
+       return true;
 end
 
 local open_sessions = 0;
@@ -133,7 +145,19 @@ function new_incoming(conn)
        open_sessions = open_sessions + 1;
        local w, log = conn.write, logger_init("s2sin"..tostring(conn):match("[a-f0-9]+$"));
        session.log = log;
-       session.sends2s = function (t) log("debug", "sending: %s", t.top_tag and t:top_tag() or t:match("^([^>]*>?)")); w(conn, tostring(t)); end
+       local filter = initialize_filters(session);
+       session.sends2s = function (t)
+               log("debug", "sending: %s", t.top_tag and t:top_tag() or t:match("^([^>]*>?)"));
+               if t.name then
+                       t = filter("stanzas/out", t);
+               end
+               if t then
+                       t = filter("bytes/out", tostring(t));
+                       if t then
+                               return w(conn, t);
+                       end
+               end
+       end
        incoming_s2s[session] = true;
        add_task(connect_timeout, function ()
                if session.conn ~= conn or
@@ -150,10 +174,13 @@ end
 
 function new_outgoing(from_host, to_host, connect)
                local host_session = { to_host = to_host, from_host = from_host, host = from_host,
-                                      notopen = true, type = "s2sout_unauthed", direction = "outgoing" };
+                                      notopen = true, type = "s2sout_unauthed", direction = "outgoing",
+                                      open_stream = session_open_stream };
                
                hosts[from_host].s2sout[to_host] = host_session;
                
+               host_session.close = destroy_session; -- This gets replaced by xmppserver_listener later
+               
                local log;
                do
                        local conn_name = "s2sout"..tostring(host_session):match("[a-f0-9]*$");
@@ -161,9 +188,15 @@ function new_outgoing(from_host, to_host, connect)
                        host_session.log = log;
                end
                
+               initialize_filters(host_session);
+               
                if connect ~= false then
                        -- Kick the connection attempting machine into life
-                       attempt_connection(host_session);
+                       if not attempt_connection(host_session) then
+                               -- Intentionally not returning here, the
+                               -- session is needed, connected or not
+                               destroy_session(host_session);
+                       end
                end
                
                if not host_session.sends2s then
@@ -180,7 +213,6 @@ function new_outgoing(from_host, to_host, connect)
                                buffer[#buffer+1] = data;
                                log("debug", "Buffered item %d: %s", #buffer, tostring(data));
                        end
-                       
                end
 
                return host_session;
@@ -189,7 +221,7 @@ end
 
 function attempt_connection(host_session, err)
        local from_host, to_host = host_session.from_host, host_session.to_host;
-       local connect_host, connect_port = idna_to_ascii(to_host), 5269;
+       local connect_host, connect_port = to_host and idna_to_ascii(to_host), 5269;
        
        if not connect_host then
                return false;
@@ -230,14 +262,6 @@ function attempt_connection(host_session, err)
                        end
                end, "_xmpp-server._tcp."..connect_host..".", "SRV");
                
-               -- Set handler for DNS timeout
-               add_task(dns_timeout, function ()
-                       if handle then
-                               adns.cancel(handle, true);
-                       end
-               end);
-               
-               log("debug", "DNS lookup for %s sent, waiting for response before we can connect", to_host);
                return true; -- Attempt in progress
        elseif host_session.srv_hosts and #host_session.srv_hosts > host_session.srv_choice then -- Not our first attempt, and we also have SRV
                host_session.srv_choice = host_session.srv_choice + 1;
@@ -262,7 +286,7 @@ end
 function try_connect(host_session, connect_host, connect_port)
        host_session.connecting = true;
        local handle;
-       handle = adns.lookup(function (reply)
+       handle = adns.lookup(function (reply, err)
                handle = nil;
                host_session.connecting = nil;
                
@@ -280,33 +304,38 @@ function try_connect(host_session, connect_host, connect_port)
                
                if reply and reply[#reply] and reply[#reply].a then
                        log("debug", "DNS reply for %s gives us %s", connect_host, reply[#reply].a);
-                       return make_connect(host_session, reply[#reply].a, connect_port);
+                       local ok, err = make_connect(host_session, reply[#reply].a, connect_port);
+                       if not ok then
+                               if not attempt_connection(host_session, err or "closed") then
+                                       err = err and (": "..err) or "";
+                                       destroy_session(host_session, "Connection failed"..err);
+                               end
+                       end
                else
                        log("debug", "DNS lookup failed to get a response for %s", connect_host);
                        if not attempt_connection(host_session, "name resolution failed") then -- Retry if we can
                                log("debug", "No other records to try for %s - destroying", host_session.to_host);
-                               destroy_session(host_session, "DNS resolution failed"); -- End of the line, we can't
+                               err = err and (": "..err) or "";
+                               destroy_session(host_session, "DNS resolution failed"..err); -- End of the line, we can't
                        end
                end
        end, connect_host, "A", "IN");
 
-       -- Set handler for DNS timeout
-       add_task(dns_timeout, function ()
-               if handle then
-                       adns.cancel(handle, true);
-               end
-       end);
-       
        return true;
 end
 
 function make_connect(host_session, connect_host, connect_port)
-       host_session.log("info", "Beginning new connection attempt to %s (%s:%d)", host_session.to_host, connect_host, connect_port);
+       (host_session.log or log)("info", "Beginning new connection attempt to %s (%s:%d)", host_session.to_host, connect_host, connect_port);
        -- Ok, we're going to try to connect
        
        local from_host, to_host = host_session.from_host, host_session.to_host;
        
-       local conn, handler = socket.tcp()
+       local conn, handler = socket.tcp();
+       
+       if not conn then
+               log("warn", "Failed to create outgoing connection, system error: %s", handler);
+               return false, handler;
+       end
 
        conn:settimeout(0);
        local success, err = conn:connect(connect_host, connect_port);
@@ -316,17 +345,30 @@ function make_connect(host_session, connect_host, connect_port)
        end
        
        local cl = connlisteners_get("xmppserver");
-       conn = wrapclient(conn, connect_host, connect_port, cl, cl.default_mode or 1, hosts[from_host].ssl_ctx, false );
+       conn = wrapclient(conn, connect_host, connect_port, cl, cl.default_mode or 1 );
        host_session.conn = conn;
        
+       local filter = initialize_filters(host_session);
+       local w, log = conn.write, host_session.log;
+       host_session.sends2s = function (t)
+               log("debug", "sending: %s", (t.top_tag and t:top_tag()) or t:match("^[^>]*>?"));
+               if t.name then
+                       t = filter("stanzas/out", t);
+               end
+               if t then
+                       t = filter("bytes/out", tostring(t));
+                       if t then
+                               return w(conn, tostring(t));
+                       end
+               end
+       end
+       
        -- Register this outgoing connection so that xmppserver_listener knows about it
        -- otherwise it will assume it is a new incoming connection
        cl.register_outgoing(conn, host_session);
        
-       local w, log = conn.write, host_session.log;
-       host_session.sends2s = function (t) log("debug", "sending: %s", (t.top_tag and t:top_tag()) or t:match("^[^>]*>?")); w(conn, tostring(t)); end
+       host_session:open_stream(from_host, to_host);
        
-       conn:write(format([[<stream:stream xmlns='jabber:server' xmlns:db='jabber:server:dialback' xmlns:stream='http://etherx.jabber.org/streams' from='%s' to='%s' version='1.0' xml:lang='en'>]], from_host, to_host));
        log("debug", "Connection attempt in progress...");
        add_task(connect_timeout, function ()
                if host_session.conn ~= conn or
@@ -342,6 +384,13 @@ function make_connect(host_session, connect_host, connect_port)
        return true;
 end
 
+function session_open_stream(session, from, to)
+       session.sends2s(st.stanza("stream:stream", {
+               xmlns='jabber:server', ["xmlns:db"]='jabber:server:dialback',
+               ["xmlns:stream"]='http://etherx.jabber.org/streams',
+               from=from, to=to, version='1.0', ["xml:lang"]='en'}):top_tag());
+end
+
 function streamopened(session, attr)
        local send = session.sends2s;
        
@@ -352,11 +401,6 @@ function streamopened(session, attr)
                session.secure = true;
        end
        
-       if session.version >= 1.0 and not (attr.to and attr.from) then
-               (session.log or log)("warn", "Remote of stream "..(session.from_host or "(unknown)").."->"..(session.to_host or "(unknown)")
-                       .." failed to specify to (%s) and/or from (%s) hostname as per RFC", tostring(attr.to), tostring(attr.from));
-       end
-       
        if session.direction == "incoming" then
                -- Send a reply stream header
                session.to_host = attr.to and nameprep(attr.to);
@@ -364,10 +408,22 @@ function streamopened(session, attr)
        
                session.streamid = uuid_gen();
                (session.log or log)("debug", "incoming s2s received <stream:stream>");
-               if session.to_host and not hosts[session.to_host] then
-                       -- Attempting to connect to a host we don't serve
-                       session:close({ condition = "host-unknown"; text = "This host does not serve "..session.to_host });
-                       return;
+               if session.to_host then
+                       if not hosts[session.to_host] then
+                               -- Attempting to connect to a host we don't serve
+                               session:close({
+                                       condition = "host-unknown";
+                                       text = "This host does not serve "..session.to_host
+                               });
+                               return;
+                       elseif hosts[session.to_host].disallow_s2s then
+                               -- Attempting to connect to a host that disallows s2s
+                               session:close({
+                                       condition = "policy-violation";
+                                       text = "Server-to-server communication is not allowed to this host";
+                               });
+                               return;
+                       end
                end
                send("<?xml version='1.0'?>");
                send(stanza("stream:stream", { xmlns='jabber:server', ["xmlns:db"]='jabber:server:dialback',
@@ -376,7 +432,7 @@ function streamopened(session, attr)
                        local features = st.stanza("stream:features");
                        
                        if session.to_host then
-                               hosts[session.to_host].events.fire_event("s2s-stream-features", { session = session, features = features });
+                               hosts[session.to_host].events.fire_event("s2s-stream-features", { origin = session, features = features });
                        else
                                (session.log or log)("warn", "No 'to' on stream header from %s means we can't offer any features", session.from_host or "unknown host");
                        end
@@ -417,11 +473,8 @@ function streamopened(session, attr)
 end
 
 function streamclosed(session)
-       (session.log or log)("debug", "</stream:stream>");
-       if session.sends2s then
-               session.sends2s("</stream:stream>");
-       end
-       session.notopen = true;
+       (session.log or log)("debug", "Received </stream:stream>");
+       session:close();
 end
 
 function initiate_dialback(session)
@@ -440,14 +493,26 @@ function verify_dialback(id, to, from, key)
 end
 
 function make_authenticated(session, host)
+       if not session.secure then
+               local local_host = session.direction == "incoming" and session.to_host or session.from_host;
+               if config.get(local_host, "core", "s2s_require_encryption") then
+                       session:close({
+                               condition = "policy-violation",
+                               text = "Encrypted server-to-server communication is required but was not "
+                                      ..((session.direction == "outgoing" and "offered") or "used")
+                       });
+               end
+       end
        if session.type == "s2sout_unauthed" then
                session.type = "s2sout";
        elseif session.type == "s2sin_unauthed" then
                session.type = "s2sin";
                if host then
+                       if not session.hosts[host] then session.hosts[host] = {}; end
                        session.hosts[host].authed = true;
                end
        elseif session.type == "s2sin" and host then
+               if not session.hosts[host] then session.hosts[host] = {}; end
                session.hosts[host].authed = true;
        else
                return false;
@@ -468,8 +533,16 @@ function mark_connected(session)
        session.log("info", session.direction.." s2s connection "..from.."->"..to.." complete");
        
        local send_to_host = send_to_host;
-       function session.send(data) send_to_host(to, from, data); end
+       function session.send(data) return send_to_host(to, from, data); end
        
+       local event_data = { session = session };
+       if session.type == "s2sout" then
+               prosody.events.fire_event("s2sout-established", event_data);
+               hosts[session.from_host].events.fire_event("s2sout-established", event_data);
+       else
+               prosody.events.fire_event("s2sin-established", event_data);
+               hosts[session.to_host].events.fire_event("s2sin-established", event_data);
+       end
        
        if session.direction == "outgoing" then
                if sendq then
@@ -485,7 +558,35 @@ function mark_connected(session)
        end
 end
 
+local resting_session = { -- Resting, not dead
+               destroyed = true;
+               type = "s2s_destroyed";
+               open_stream = function (session)
+                       session.log("debug", "Attempt to open stream on resting session");
+               end;
+               close = function (session)
+                       session.log("debug", "Attempt to close already-closed session");
+               end;
+               filter = function (type, data) return data; end;
+       }; resting_session.__index = resting_session;
+
+function retire_session(session, reason)
+       local log = session.log or log;
+       for k in pairs(session) do
+               if k ~= "trace" and k ~= "log" and k ~= "id" then
+                       session[k] = nil;
+               end
+       end
+
+       session.destruction_reason = reason;
+
+       function session.send(data) log("debug", "Discarding data sent to resting session: %s", tostring(data)); end
+       function session.data(data) log("debug", "Discarding data received from resting session: %s", tostring(data)); end
+       return setmetatable(session, resting_session);
+end
+
 function destroy_session(session, reason)
+       if session.destroyed then return; end
        (session.log or log)("info", "Destroying "..tostring(session.direction).." session "..tostring(session.from_host).."->"..tostring(session.to_host));
        
        if session.direction == "outgoing" then
@@ -495,11 +596,21 @@ function destroy_session(session, reason)
                incoming_s2s[session] = nil;
        end
        
-       for k in pairs(session) do
-               if k ~= "trace" then
-                       session[k] = nil;
+       local event_data = { session = session, reason = reason };
+       if session.type == "s2sout" then
+               prosody.events.fire_event("s2sout-destroyed", event_data);
+               if hosts[session.from_host] then
+                       hosts[session.from_host].events.fire_event("s2sout-destroyed", event_data);
+               end
+       elseif session.type == "s2sin" then
+               prosody.events.fire_event("s2sin-destroyed", event_data);
+               if hosts[session.to_host] then
+                       hosts[session.to_host].events.fire_event("s2sin-destroyed", event_data);
                end
        end
+       
+       retire_session(session, reason); -- Clean session until it is GC'd
+       return true;
 end
 
 return _M;