s2smanager, mod_compression, mod_tls: Changed event.session to event.origin for s2s...
[prosody.git] / core / s2smanager.lua
index 158536d8d685873627e3d9e248c6818ba10a08fe..aba99ee07482c1ab4fda9f3ec16bb6179147e139 100644 (file)
@@ -1,4 +1,4 @@
--- Prosody IM v0.4
+-- Prosody IM
 -- Copyright (C) 2008-2009 Matthew Wild
 -- Copyright (C) 2008-2009 Waqas Hussain
 -- 
 local hosts = hosts;
 local sessions = sessions;
 local core_process_stanza = function(a, b) core_process_stanza(a, b); end
+local add_task = require "util.timer".add_task;
 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, print, newproxy, error, tonumber
-    = tostring, pairs, ipairs, getmetatable, print, newproxy, error, tonumber;
+local tostring, pairs, ipairs, getmetatable, newproxy, error, tonumber
+    = tostring, pairs, ipairs, getmetatable, newproxy, error, tonumber;
 
 local idna_to_ascii = require "util.encodings".idna.to_ascii;
 local connlisteners_get = require "net.connlisteners".get;
@@ -26,6 +27,7 @@ local st = require "stanza";
 local stanza = st.stanza;
 local nameprep = require "util.encodings".stringprep.nameprep;
 
+local fire_event = require "core.eventmanager".fire_event;
 local uuid_gen = require "util.uuid".generate;
 
 local logger_init = require "util.logger".init;
@@ -34,21 +36,24 @@ local log = logger_init("s2smanager");
 
 local sha256_hash = require "util.hashes".sha256;
 
-local dialback_secret = sha256_hash(tostring{} .. math.random() .. socket.gettime(), true);
-
-local dns = require "net.dns";
+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 max_dns_depth = config.get("*", "core", "dns_max_depth") or 3;
 
 incoming_s2s = {};
+_G.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
 
-local function bounce_sendq(session)
+local function bounce_sendq(session, reason)
        local sendq = session.sendq;
        if sendq then
-               session.log("debug", "sending error replies for "..#sendq.." queued stanzas because of failed outgoing connection to "..tostring(session.to_host));
+               session.log("info", "sending error replies for "..#sendq.." queued stanzas because of failed outgoing connection to "..tostring(session.to_host));
                local dummy = {
                        type = "s2sin";
                        send = function(s)
@@ -63,6 +68,9 @@ local function bounce_sendq(session)
                                reply.attr.type = "error";
                                reply:tag("error", {type = "cancel"})
                                        :tag("remote-server-not-found", {xmlns = "urn:ietf:params:xml:ns:xmpp-stanzas"}):up();
+                               if reason then
+                                       reply:tag("text", {xmlns = "urn:ietf:params:xml:ns:xmpp-stanzas"}):text("Connection failed: "..reason):up();
+                               end
                                core_process_stanza(dummy, reply);
                        end
                        sendq[i] = nil;
@@ -72,15 +80,15 @@ local function bounce_sendq(session)
 end
 
 function send_to_host(from_host, to_host, data)
+       if not hosts[from_host] then
+               log("warn", "Attempt to send stanza from %s - a host we don't serve", from_host);
+               return false;
+       end
        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" 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) and ((not data.xmlns) or data.xmlns == "jabber:client" or data.xmlns == "jabber:server") then
                        (host.log or log)("debug", "trying to send over unauthed s2sout to "..to_host);
-                       if not host.notopen and not host.dialback_key then
-                               host.log("debug", "dialback had not been initiated");
-                               initiate_dialback(host);
-                       end
                        
                        -- Queue stanza until we are able to send it
                        if host.sendq then t_insert(host.sendq, {tostring(data), st.reply(data)});
@@ -103,9 +111,14 @@ function send_to_host(from_host, to_host, data)
        else
                log("debug", "opening a new outgoing connection for this stanza");
                local host_session = new_outgoing(from_host, to_host);
+
                -- Store in buffer
                host_session.sendq = { {tostring(data), st.reply(data)} };
-               if not host_session.conn then destroy_session(host_session); end
+               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);
+               end
        end
 end
 
@@ -119,13 +132,27 @@ function new_incoming(conn)
        end
        open_sessions = open_sessions + 1;
        local w, log = conn.write, logger_init("s2sin"..tostring(conn):match("[a-f0-9]+$"));
-       session.sends2s = function (t) log("debug", "sending: %s", tostring(t)); w(tostring(t)); end
+       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
        incoming_s2s[session] = true;
+       add_task(connect_timeout, function ()
+               if session.conn ~= conn or
+                  session.type == "s2sin" then
+                       return; -- Ok, we're connect[ed|ing]
+               end
+               -- Not connected, need to close session and clean up
+               (session.log or log)("warn", "Destroying incomplete session %s->%s due to inactivity",
+                   session.from_host or "(unknown)", session.to_host or "(unknown)");
+               session:close("connection-timeout");
+       end);
        return session;
 end
 
-function new_outgoing(from_host, to_host)
-               local host_session = { to_host = to_host, from_host = from_host, notopen = true, type = "s2sout_unauthed", direction = "outgoing" };
+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",
+                                      open_stream = session_open_stream };
+               
                hosts[from_host].s2sout[to_host] = host_session;
                
                local log;
@@ -135,84 +162,212 @@ function new_outgoing(from_host, to_host)
                        host_session.log = log;
                end
                
-               attempt_connection(host_session);
+               if connect ~= false then
+                       -- Kick the connection attempting machine into life
+                       attempt_connection(host_session);
+               end
                
+               if not host_session.sends2s then
+                       -- A sends2s which buffers data (until the stream is opened)
+                       -- note that data in this buffer will be sent before the stream is authed
+                       -- and will not be ack'd in any way, successful or otherwise
+                       local buffer;
+                       function host_session.sends2s(data)
+                               if not buffer then
+                                       buffer = {};
+                                       host_session.send_buffer = buffer;
+                               end
+                               log("debug", "Buffering data on unconnected s2sout to %s", to_host);
+                               buffer[#buffer+1] = data;
+                               log("debug", "Buffered item %d: %s", #buffer, tostring(data));
+                       end
+               end
+
                return host_session;
 end
 
 
 function attempt_connection(host_session, err)
        local from_host, to_host = host_session.from_host, host_session.to_host;
-       local conn, handler = socket.tcp()
-
        local connect_host, connect_port = idna_to_ascii(to_host), 5269;
        
+       if not connect_host then
+               return false;
+       end
+       
        if not err then -- This is our first attempt
-               local answer = dns.lookup("_xmpp-server._tcp."..connect_host..".", "SRV");
-               
-               if answer then
-                       log("debug", to_host.." has SRV records, handling...");
-                       local srv_hosts = {};
-                       host_session.srv_hosts = srv_hosts;
-                       for _, record in ipairs(answer) do
-                               t_insert(srv_hosts, record.srv);
+               log("debug", "First attempt to connect to %s, starting with SRV lookup...", to_host);
+               host_session.connecting = true;
+               local handle;
+               handle = adns.lookup(function (answer)
+                       handle = nil;
+                       host_session.connecting = nil;
+                       if answer then
+                               log("debug", to_host.." has SRV records, handling...");
+                               local srv_hosts = {};
+                               host_session.srv_hosts = srv_hosts;
+                               for _, record in ipairs(answer) do
+                                       t_insert(srv_hosts, record.srv);
+                               end
+                               t_sort(srv_hosts, compare_srv_priorities);
+                               
+                               local srv_choice = srv_hosts[1];
+                               host_session.srv_choice = 1;
+                               if srv_choice then
+                                       connect_host, connect_port = srv_choice.target or to_host, srv_choice.port or connect_port;
+                                       log("debug", "Best record found, will connect to %s:%d", connect_host, connect_port);
+                               end
+                       else
+                               log("debug", to_host.." has no SRV records, falling back to A");
                        end
-                       t_sort(srv_hosts, compare_srv_priorities);
-                       
-                       local srv_choice = srv_hosts[1];
-                       host_session.srv_choice = 1;
-                       if srv_choice then
-                               connect_host, connect_port = srv_choice.target or to_host, srv_choice.port or connect_port;
-                               log("debug", "Best record found, will connect to %s:%d", connect_host, connect_port);
+                       -- Try with SRV, or just the plain hostname if no SRV
+                       local ok, err = try_connect(host_session, connect_host, connect_port);
+                       if not ok then
+                               if not attempt_connection(host_session, err) then
+                                       -- No more attempts will be made
+                                       destroy_session(host_session, err);
+                               end
                        end
-               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;
                local srv_choice = host_session.srv_hosts[host_session.srv_choice];
                connect_host, connect_port = srv_choice.target or to_host, srv_choice.port or connect_port;
-               host_session.log("debug", "Connection failed (%s). Attempt #%d: This time to %s:%d", tostring(err), host_session.srv_choice, connect_host, connect_port);
+               host_session.log("info", "Connection failed (%s). Attempt #%d: This time to %s:%d", tostring(err), host_session.srv_choice, connect_host, connect_port);
        else
-               host_session.log("debug", "Out of connection options, can't connect to %s", tostring(host_session.to_host));
+               host_session.log("info", "Out of connection options, can't connect to %s", tostring(host_session.to_host));
                -- We're out of options
                return false;
        end
        
        if not (connect_host and connect_port) then
                -- Likely we couldn't resolve DNS
+               log("warn", "Hmm, we're without a host (%s) and port (%s) to connect to for %s, giving up :(", tostring(connect_host), tostring(connect_port), tostring(to_host));
                return false;
        end
        
+       return try_connect(host_session, connect_host, connect_port);
+end
+
+function try_connect(host_session, connect_host, connect_port)
+       host_session.connecting = true;
+       local handle;
+       handle = adns.lookup(function (reply)
+               handle = nil;
+               host_session.connecting = nil;
+               
+               -- COMPAT: This is a compromise for all you CNAME-(ab)users :)
+               if not (reply and reply[#reply] and reply[#reply].a) then
+                       local count = max_dns_depth;
+                       reply = dns.peek(connect_host, "CNAME", "IN");
+                       while count > 0 and reply and reply[#reply] and not reply[#reply].a and reply[#reply].cname do
+                               log("debug", "Looking up %s (DNS depth is %d)", tostring(reply[#reply].cname), count);
+                               reply = dns.peek(reply[#reply].cname, "A", "IN") or dns.peek(reply[#reply].cname, "CNAME", "IN");
+                               count = count - 1;
+                       end
+               end
+               -- end of CNAME resolving
+               
+               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);
+               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
+                       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);
        -- 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()
+       
+       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);
        if not success and err ~= "timeout" then
-               log("warn", "s2s connect() failed: %s", err);
-               return false;
+               log("warn", "s2s connect() to %s (%s:%d) failed: %s", host_session.to_host, connect_host, connect_port, err);
+               return false, err;
        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;
        
        -- 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 = conn.write;
-       host_session.sends2s = function (t) log("debug", "sending: %s", tostring(t)); w(tostring(t)); end
+       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'>]], from_host, to_host));
+       log("debug", "Connection attempt in progress...");
+       add_task(connect_timeout, function ()
+               if host_session.conn ~= conn or
+                  host_session.type == "s2sout" or
+                  host_session.connecting then
+                       return; -- Ok, we're connect[ed|ing]
+               end
+               -- Not connected, need to close session and clean up
+               (host_session.log or log)("warn", "Destroying incomplete session %s->%s due to inactivity",
+                   host_session.from_host or "(unknown)", host_session.to_host or "(unknown)");
+               host_session:close("connection-timeout");
+       end);
        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;
        
        -- TODO: #29: SASL/TLS on s2s streams
-       session.version = 0; --tonumber(attr.version) or 0;
+       session.version = tonumber(attr.version) or 0;
+       
+       if session.secure == false then
+               session.secure = true;
+       end
        
        if session.version >= 1.0 and not (attr.to and attr.from) then
-               log("warn", (session.to_host or "(unknown)").." failed to specify 'to' or 'from' hostname as per RFC");
+               (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
@@ -222,35 +377,63 @@ function streamopened(session, attr)
        
                session.streamid = uuid_gen();
                (session.log or log)("debug", "incoming s2s received <stream:stream>");
-               send("<?xml version='1.0'?>");
-               send(stanza("stream:stream", { xmlns='jabber:server', ["xmlns:db"]='jabber:server:dialback', 
-                               ["xmlns:stream"]='http://etherx.jabber.org/streams', id=session.streamid, from=session.to_host }):top_tag());
                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;
                end
+               send("<?xml version='1.0'?>");
+               send(stanza("stream:stream", { xmlns='jabber:server', ["xmlns:db"]='jabber:server:dialback',
+                               ["xmlns:stream"]='http://etherx.jabber.org/streams', id=session.streamid, from=session.to_host, to=session.from_host, version=(session.version > 0 and "1.0" or nil) }):top_tag());
                if session.version >= 1.0 then
-                       send(st.stanza("stream:features")
-                                       :tag("dialback", { xmlns='urn:xmpp:features:dialback' }):tag("optional"):up():up());
+                       local features = st.stanza("stream:features");
+                       
+                       if session.to_host then
+                               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
+                       
+                       log("debug", "Sending stream features: %s", tostring(features));
+                       send(features);
                end
        elseif session.direction == "outgoing" then
                -- If we are just using the connection for verifying dialback keys, we won't try and auth it
                if not attr.id then error("stream response did not give us a streamid!!!"); end
                session.streamid = attr.id;
        
-               if not session.dialback_verifying then
-                       initiate_dialback(session);
-               else
-                       mark_connected(session);
+               -- Send unauthed buffer
+               -- (stanzas which are fine to send before dialback)
+               -- Note that this is *not* the stanza queue (which
+               -- we can only send if auth succeeds) :)
+               local send_buffer = session.send_buffer;
+               if send_buffer and #send_buffer > 0 then
+                       log("debug", "Sending s2s send_buffer now...");
+                       for i, data in ipairs(send_buffer) do
+                               session.sends2s(tostring(data));
+                               send_buffer[i] = nil;
+                       end
+               end
+               session.send_buffer = nil;
+       
+               -- If server is pre-1.0, don't wait for features, just do dialback
+               if session.version < 1.0 then
+                       if not session.dialback_verifying then
+                               log("debug", "Initiating dialback...");
+                               initiate_dialback(session);
+                       else
+                               mark_connected(session);
+                       end
                end
        end
-
        session.notopen = nil;
 end
 
 function streamclosed(session)
-       session.send("</stream:stream>");
+       (session.log or log)("debug", "</stream:stream>");
+       if session.sends2s then
+               session.sends2s("</stream:stream>");
+       end
        session.notopen = true;
 end
 
@@ -262,7 +445,7 @@ function initiate_dialback(session)
 end
 
 function generate_dialback(id, to, from)
-       return sha256_hash(id..to..from..dialback_secret, true);
+       return sha256_hash(id..to..from..hosts[from].dialback_secret, true);
 end
 
 function verify_dialback(id, to, from, key)
@@ -270,6 +453,16 @@ 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
@@ -282,19 +475,20 @@ function make_authenticated(session, host)
        else
                return false;
        end
-       session.log("info", "connection is now authenticated");
+       session.log("debug", "connection %s->%s is now authenticated", session.from_host or "(unknown)", session.to_host or "(unknown)");
        
        mark_connected(session);
        
        return true;
 end
 
+-- Stream is authorised, and ready for normal stanzas
 function mark_connected(session)
        local sendq, send = session.sendq, session.sends2s;
        
        local from, to = session.from_host, session.to_host;
        
-       session.log("debug", session.direction.." s2s connection "..from.."->"..to.." is now complete");
+       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
@@ -309,16 +503,17 @@ function mark_connected(session)
                        end
                        session.sendq = nil;
                end
+               
+               session.srv_hosts = nil;
        end
 end
 
-function destroy_session(session)
+function destroy_session(session, reason)
        (session.log or log)("info", "Destroying "..tostring(session.direction).." session "..tostring(session.from_host).."->"..tostring(session.to_host));
        
-       
        if session.direction == "outgoing" then
                hosts[session.from_host].s2sout[session.to_host] = nil;
-               bounce_sendq(session);
+               bounce_sendq(session, reason);
        elseif session.direction == "incoming" then
                incoming_s2s[session] = nil;
        end