From 68bf2a395659bf458efe9e49e4c8abed90fd084f Mon Sep 17 00:00:00 2001 From: Matthew Wild Date: Mon, 23 Jan 2012 16:28:20 +0000 Subject: s2smanager, mod_s2s, mod_s2s/s2sout: Split connection handling out of s2smanager into mod_s2s, and further split connection logic for s2sout to a module lib, s2sout.lib.lua --- core/s2smanager.lua | 581 +-------------------------------------------- plugins/s2s/mod_s2s.lua | 447 ++++++++++++++++++++++++++++++++++ plugins/s2s/s2sout.lib.lua | 314 ++++++++++++++++++++++++ 3 files changed, 772 insertions(+), 570 deletions(-) create mode 100644 plugins/s2s/mod_s2s.lua create mode 100644 plugins/s2s/s2sout.lib.lua diff --git a/core/s2smanager.lua b/core/s2smanager.lua index f44921c3..e61aaccb 100644 --- a/core/s2smanager.lua +++ b/core/s2smanager.lua @@ -9,18 +9,13 @@ 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, newproxy, type, error, tonumber, setmetatable = tostring, pairs, ipairs, getmetatable, newproxy, type, 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 st = require "stanza"; @@ -41,11 +36,13 @@ 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 15; local max_dns_depth = config.get("*", "core", "dns_max_depth") or 3; +local cfg_sources = config.get("*", "core", "s2s_interface") + or config.get("*", "core", "interface"); local sources; +--FIXME: s2sout should create its own resolver w/ timeout dns.settimeout(dns_timeout); local prosody = _G.prosody; @@ -55,89 +52,6 @@ local incoming_s2s = incoming_s2s; module "s2smanager" -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 - 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) - (session.log or log)("error", "Replying to to an s2s error reply, please report this! Traceback: %s", get_traceback()); - end; - dummy = true; - }; - for i, data in ipairs(sendq) do - local reply = data[2]; - 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(); - if reason then - reply:tag("text", {xmlns = "urn:ietf:params:xml:ns:xmpp-stanzas"}) - :text("Server-to-server connection failed: "..reason):up(); - end - core_process_stanza(dummy, reply); - end - sendq[i] = nil; - end - session.sendq = nil; - end -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" 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), 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 - if host.from_host ~= from_host then - log("error", "WARNING! This might, possibly, be a bug, but it might not..."); - log("error", "We are going to send from %s instead of %s", tostring(host.from_host), tostring(from_host)); - end - host.sends2s(data); - host.log("debug", "stanza sent over "..host.type); - end - 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), 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); - 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; function new_incoming(conn) @@ -147,491 +61,18 @@ function new_incoming(conn) getmetatable(session.trace).__gc = function () open_sessions = open_sessions - 1; end; end open_sessions = open_sessions + 1; - local w, log = conn.write, logger_init("s2sin"..tostring(conn):match("[a-f0-9]+$")); - session.log = log; - local filter = initialize_filters(session); - session.sends2s = function (t) - log("debug", "sending: %s", t.top_tag and t:top_tag() or t:match("^([^>]*>?)")); - if t.name then - t = filter("stanzas/out", t); - end - if t then - t = filter("bytes/out", tostring(t)); - if t then - return w(conn, t); - end - end - end + session.log = logger_init("s2sin"..tostring(conn):match("[a-f0-9]+$")); 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)("debug", "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, 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; - - 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]*$"); - log = logger_init(conn_name); - host_session.log = log; - end - - initialize_filters(host_session); - - if connect ~= false then - -- Kick the connection attempting machine into life - 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 - -- 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 connect_host, connect_port = to_host and idna_to_ascii(to_host), 5269; - - if not connect_host then - return false; - end - - if not err then -- This is our first attempt - 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 - if #srv_hosts == 1 and srv_hosts[1].target == "." then - log("debug", to_host.." does not provide a XMPP service"); - destroy_session(host_session, err); -- Nothing to see here - return; - 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 - -- 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, "_xmpp-server._tcp."..connect_host..".", "SRV"); - - return true; -- Attempt in progress - elseif host_session.ip_hosts then - return try_connect(host_session, connect_host, connect_port, err); - 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("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("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_next_ip(host_session) - host_session.connecting = nil; - host_session.ip_choice = host_session.ip_choice + 1; - local ip = host_session.ip_hosts[host_session.ip_choice]; - local ok, err= make_connect(host_session, ip.ip, ip.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 -end - -function try_connect(host_session, connect_host, connect_port, err) - host_session.connecting = true; - - if not err then - local IPs = {}; - host_session.ip_hosts = IPs; - local handle4, handle6; - local has_other = false; - - if not sources then - sources = {}; - local cfg_sources = config.get("*", "core", "interface") or connlisteners_get("xmppserver").default_interface; - if type(cfg_sources) == "string" then - cfg_sources = { cfg_sources }; - end - for i, source in ipairs(cfg_sources) do - if source == "*" then - sources[i] = new_ip("0.0.0.0", "IPv4"); - else - sources[i] = new_ip(source, (source:find(":") and "IPv6") or "IPv4"); - end - end - end - - handle4 = adns.lookup(function (reply, err) - handle4 = 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 - for _, ip in ipairs(reply) do - log("debug", "DNS reply for %s gives us %s", connect_host, ip.a); - IPs[#IPs+1] = new_ip(ip.a, "IPv4"); - end - end - - if has_other then - if #IPs > 0 then - rfc3484_dest(host_session.ip_hosts, sources); - for i = 1, #IPs do - IPs[i] = {ip = IPs[i], port = connect_port}; - end - host_session.ip_choice = 0; - try_next_ip(host_session); - else - log("debug", "DNS lookup failed to get a response for %s", connect_host); - host_session.ip_hosts = nil; - 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); - err = err and (": "..err) or ""; - destroy_session(host_session, "DNS resolution failed"..err); -- End of the line, we can't - end - end - else - has_other = true; - end - end, connect_host, "A", "IN"); - - handle6 = adns.lookup(function (reply, err) - handle6 = nil; - - if reply and reply[#reply] and reply[#reply].aaaa then - for _, ip in ipairs(reply) do - log("debug", "DNS reply for %s gives us %s", connect_host, ip.aaaa); - IPs[#IPs+1] = new_ip(ip.aaaa, "IPv6"); - end - end - - if has_other then - if #IPs > 0 then - rfc3484_dest(host_session.ip_hosts, sources); - for i = 1, #IPs do - IPs[i] = {ip = IPs[i], port = connect_port}; - end - host_session.ip_choice = 0; - try_next_ip(host_session); - else - log("debug", "DNS lookup failed to get a response for %s", connect_host); - host_session.ip_hosts = nil; - 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); - err = err and (": "..err) or ""; - destroy_session(host_session, "DNS resolution failed"..err); -- End of the line, we can't - end - end - else - has_other = true; - end - end, connect_host, "AAAA", "IN"); - - return true; - elseif host_session.ip_hosts and #host_session.ip_hosts > host_session.ip_choice then -- Not our first attempt, and we also have IPs left to try - try_next_ip(host_session); - else - host_session.ip_hosts = nil; - if not attempt_connection(host_session, "out of IP addresses") then -- Retry if we can - log("debug", "No other records to try for %s - destroying", host_session.to_host); - err = err and (": "..err) or ""; - destroy_session(host_session, "Connecting failed"..err); -- End of the line, we can't - return false; - end - end - - return true; -end - -function make_connect(host_session, connect_host, connect_port) - (host_session.log or log)("info", "Beginning new connection attempt to %s ([%s]:%d)", host_session.to_host, connect_host.addr, 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; - if connect_host.proto == "IPv4" then - conn, handler = socket.tcp(); - else - conn, handler = socket.tcp6(); - end - - 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.addr, connect_port); - if not success and err ~= "timeout" then - log("warn", "s2s connect() to %s (%s:%d) failed: %s", host_session.to_host, connect_host.addr, connect_port, err); - return false, err; - end - - local cl = connlisteners_get("xmppserver"); - conn = wrapclient(conn, connect_host.addr, 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); - - host_session:open_stream(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 - -local function check_cert_status(session) - local conn = session.conn:socket() - local cert - if conn.getpeercertificate then - cert = conn:getpeercertificate() - end - - if cert then - local chain_valid, errors = conn:getpeerverification() - -- Is there any interest in printing out all/the number of errors here? - if not chain_valid then - (session.log or log)("debug", "certificate chain validation result: invalid"); - session.cert_chain_status = "invalid"; - else - (session.log or log)("debug", "certificate chain validation result: valid"); - session.cert_chain_status = "valid"; - - local host = session.direction == "incoming" and session.from_host or session.to_host - - -- We'll go ahead and verify the asserted identity if the - -- connecting server specified one. - if host then - if cert_verify_identity(host, "xmpp-server", cert) then - session.cert_identity_status = "valid" - else - session.cert_identity_status = "invalid" - end - end - end - end -end - -function streamopened(session, attr) - local send = session.sends2s; - - -- TODO: #29: SASL/TLS on s2s streams - session.version = tonumber(attr.version) or 0; - - -- TODO: Rename session.secure to session.encrypted - if session.secure == false then - session.secure = true; - end - - if session.direction == "incoming" then - -- Send a reply stream header - session.to_host = attr.to and nameprep(attr.to); - session.from_host = attr.from and nameprep(attr.from); - - session.streamid = uuid_gen(); - (session.log or log)("debug", "Incoming s2s received "); - 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 - - if session.secure and not session.cert_chain_status then check_cert_status(session); end - - send(""); - 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 - 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 session.secure and not session.cert_chain_status then check_cert_status(session); end - - -- 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.log or log)("debug", "Received "); - session:close(); -end - -function initiate_dialback(session) - -- generate dialback key - session.dialback_key = generate_dialback(session.streamid, session.to_host, session.from_host); - session.sends2s(format("%s", session.from_host, session.to_host, session.dialback_key)); - session.log("info", "sent dialback key on outgoing s2s stream"); -end - -function generate_dialback(id, to, from) - return sha256_hash(id..to..from..hosts[from].dialback_secret, true); -end - -function verify_dialback(id, to, from, key) - return key == generate_dialback(id, to, from); + local host_session = { to_host = to_host, from_host = from_host, host = from_host, + notopen = true, type = "s2sout_unauthed", direction = "outgoing" }; + hosts[from_host].s2sout[to_host] = host_session; + local conn_name = "s2sout"..tostring(host_session):match("[a-f0-9]*$"); + host_session.log = logger_init(conn_name); + return host_session; end function make_authenticated(session, host) @@ -733,7 +174,7 @@ function destroy_session(session, reason) if session.direction == "outgoing" then hosts[session.from_host].s2sout[session.to_host] = nil; - bounce_sendq(session, reason); + session:bounce_sendq(reason); elseif session.direction == "incoming" then incoming_s2s[session] = nil; end diff --git a/plugins/s2s/mod_s2s.lua b/plugins/s2s/mod_s2s.lua new file mode 100644 index 00000000..5be4d84b --- /dev/null +++ b/plugins/s2s/mod_s2s.lua @@ -0,0 +1,447 @@ +-- Prosody IM +-- 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. +-- + +module:set_global(); + +local tostring, type = tostring, type; +local xpcall, traceback = xpcall, debug.traceback; + +local add_task = require "util.timer".add_task; +local st = require "util.stanza"; +local initialize_filters = require "util.filters".initialize; +local new_xmpp_stream = require "util.xmppstream".new; +local s2s_new_incoming = require "core.s2smanager".new_incoming; +local s2s_new_outgoing = require "core.s2smanager".new_outgoing; +local s2s_destroy_session = require "core.s2smanager".destroy_session; + +local s2sout = module:require("s2sout"); + +local connect_timeout = module:get_option_number("s2s_timeout", 60); + +local sessions = module:shared("sessions"); + +--- Handle stanzas to remote domains + +local bouncy_stanzas = { message = true, presence = true, iq = true }; +local function bounce_sendq(session, reason) + local sendq = session.sendq; + if not sendq then return; end + 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) + (session.log or log)("error", "Replying to to an s2s error reply, please report this! Traceback: %s", get_traceback()); + end; + dummy = true; + }; + for i, data in ipairs(sendq) do + local reply = data[2]; + 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(); + if reason then + reply:tag("text", {xmlns = "urn:ietf:params:xml:ns:xmpp-stanzas"}) + :text("Server-to-server connection failed: "..reason):up(); + end + core_process_stanza(dummy, reply); + end + sendq[i] = nil; + end + session.sendq = nil; +end + +function send_to_host(from_host, to_host, stanza) + 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 (stanza.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(stanza), stanza.attr.type ~= "error" and stanza.attr.type ~= "result" and st.reply(stanza)}); + else host.sendq = { {tostring(stanza), stanza.attr.type ~= "error" and stanza.attr.type ~= "result" and st.reply(stanza)} }; end + host.log("debug", "stanza [%s] queued ", stanza.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(stanza)); + return false; + else + (host.log or log)("debug", "going to send stanza to "..to_host.." from "..from_host); + -- FIXME + if host.from_host ~= from_host then + log("error", "WARNING! This might, possibly, be a bug, but it might not..."); + log("error", "We are going to send from %s instead of %s", tostring(host.from_host), tostring(from_host)); + end + host.sends2s(stanza); + host.log("debug", "stanza sent over "..host.type); + end + else + log("debug", "opening a new outgoing connection for this stanza"); + local host_session = s2s_new_outgoing(from_host, to_host); + + -- Store in buffer + host_session.bounce_sendq = bounce_sendq; + host_session.sendq = { {tostring(stanza), stanza.attr.type ~= "error" and stanza.attr.type ~= "result" and st.reply(stanza)} }; + log("debug", "stanza [%s] queued until connection complete", tostring(stanza.name)); + if (not host_session.connecting) and (not host_session.conn) then + log("warn", "Connection to %s failed already, destroying session...", to_host); + if not s2s_destroy_session(host_session, "Connection failed") then + -- Already destroyed, we need to bounce our stanza + host_session:bounce_sendq(host_session.destruction_reason); + end + return false; + end + s2sout.initiate_connection(host_session); + end + return true; +end + +module:hook("route/remote", function (event) + return send_to_host(event.from_host, event.to_host, event.stanza); +end); + +--- Helper to check that a session peer's certificate is valid +local function check_cert_status(session) + local conn = session.conn:socket() + local cert + if conn.getpeercertificate then + cert = conn:getpeercertificate() + end + + if cert then + local chain_valid, errors = conn:getpeerverification() + -- Is there any interest in printing out all/the number of errors here? + if not chain_valid then + (session.log or log)("debug", "certificate chain validation result: invalid"); + session.cert_chain_status = "invalid"; + else + (session.log or log)("debug", "certificate chain validation result: valid"); + session.cert_chain_status = "valid"; + + local host = session.direction == "incoming" and session.from_host or session.to_host + + -- We'll go ahead and verify the asserted identity if the + -- connecting server specified one. + if host then + if cert_verify_identity(host, "xmpp-server", cert) then + session.cert_identity_status = "valid" + else + session.cert_identity_status = "invalid" + end + end + end + end +end + +--- XMPP stream event handlers + +local stream_callbacks = { default_ns = "jabber:server", handlestanza = core_process_stanza }; + +local xmlns_xmpp_streams = "urn:ietf:params:xml:ns:xmpp-streams"; + +function stream_callbacks.streamopened(session, attr) + local send = session.sends2s; + + -- TODO: #29: SASL/TLS on s2s streams + session.version = tonumber(attr.version) or 0; + + -- TODO: Rename session.secure to session.encrypted + if session.secure == false then + session.secure = true; + end + + if session.direction == "incoming" then + -- Send a reply stream header + session.to_host = attr.to and nameprep(attr.to); + session.from_host = attr.from and nameprep(attr.from); + + session.streamid = uuid_gen(); + (session.log or log)("debug", "Incoming s2s received "); + 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 + + if session.secure and not session.cert_chain_status then check_cert_status(session); end + + send(""); + 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 + 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 session.secure and not session.cert_chain_status then check_cert_status(session); end + + -- 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 + s2s_mark_connected(session); + end + end + end + session.notopen = nil; +end + +function stream_callbacks.streamclosed(session) + (session.log or log)("debug", "Received "); + session:close(); +end + +function stream_callbacks.streamdisconnected(session, err) + if err and err ~= "closed" then + (session.log or log)("debug", "s2s connection attempt failed: %s", err); + if s2sout.attempt_connection(session, err) then + (session.log or log)("debug", "...so we're going to try another target"); + return true; -- Session lives for now + end + end + (session.log or log)("info", "s2s disconnected: %s->%s (%s)", tostring(session.from_host), tostring(session.to_host), tostring(err or "closed")); + sessions[session.conn] = nil; + s2s_destroy_session(session, err); +end + +function stream_callbacks.error(session, error, data) + if error == "no-stream" then + session:close("invalid-namespace"); + elseif error == "parse-error" then + session.log("debug", "Server-to-server XML parse error: %s", tostring(error)); + session:close("not-well-formed"); + elseif error == "stream-error" then + local condition, text = "undefined-condition"; + for child in data:children() do + if child.attr.xmlns == xmlns_xmpp_streams then + if child.name ~= "text" then + condition = child.name; + else + text = child:get_text(); + end + if condition ~= "undefined-condition" and text then + break; + end + end + end + text = condition .. (text and (" ("..text..")") or ""); + session.log("info", "Session closed by remote with error: %s", text); + session:close(nil, text); + end +end + +local function handleerr(err) log("error", "Traceback[s2s]: %s: %s", tostring(err), traceback()); end +function stream_callbacks.handlestanza(session, stanza) + if stanza.attr.xmlns == "jabber:client" then --COMPAT: Prosody pre-0.6.2 may send jabber:client + stanza.attr.xmlns = nil; + end + stanza = session.filter("stanzas/in", stanza); + if stanza then + return xpcall(function () return core_process_stanza(session, stanza) end, handleerr); + end +end + +local listener = { default_port = 5269, default_mode = "*a", default_interface = "*" }; + +--- Session methods +local stream_xmlns_attr = {xmlns='urn:ietf:params:xml:ns:xmpp-streams'}; +local default_stream_attr = { ["xmlns:stream"] = "http://etherx.jabber.org/streams", xmlns = stream_callbacks.default_ns, version = "1.0", id = "" }; +local function session_close(session, reason, remote_reason) + local log = session.log or log; + if session.conn then + if session.notopen then + session.sends2s(""); + session.sends2s(st.stanza("stream:stream", default_stream_attr):top_tag()); + end + if reason then + if type(reason) == "string" then -- assume stream error + log("info", "Disconnecting %s[%s], is: %s", session.host or "(unknown host)", session.type, reason); + session.sends2s(st.stanza("stream:error"):tag(reason, {xmlns = 'urn:ietf:params:xml:ns:xmpp-streams' })); + elseif type(reason) == "table" then + if reason.condition then + local stanza = st.stanza("stream:error"):tag(reason.condition, stream_xmlns_attr):up(); + if reason.text then + stanza:tag("text", stream_xmlns_attr):text(reason.text):up(); + end + if reason.extra then + stanza:add_child(reason.extra); + end + log("info", "Disconnecting %s[%s], is: %s", session.host or "(unknown host)", session.type, tostring(stanza)); + session.sends2s(stanza); + elseif reason.name then -- a stanza + log("info", "Disconnecting %s->%s[%s], is: %s", session.from_host or "(unknown host)", session.to_host or "(unknown host)", session.type, tostring(reason)); + session.sends2s(reason); + end + end + end + session.sends2s(""); + if session.notopen or not session.conn:close() then + session.conn:close(true); -- Force FIXME: timer? + end + session.conn:close(); + listener.ondisconnect(session.conn, remote_reason or (reason and (reason.text or reason.condition)) or reason or "stream closed"); + end +end + +-- Session initialization logic shared by incoming and outgoing +local function initialize_session(session) + local stream = new_xmpp_stream(session, stream_callbacks); + session.stream = stream; + + session.notopen = true; + + function session.reset_stream() + session.notopen = true; + session.stream:reset(); + end + + local filter = session.filter; + function session.data(data) + data = filter("bytes/in", data); + if data then + local ok, err = stream:feed(data); + if ok then return; end + (session.log or log)("warn", "Received invalid XML: %s", data); + (session.log or log)("warn", "Problem was: %s", err); + session:close("not-well-formed"); + end + end + + session.close = session_close; + + local handlestanza = stream_callbacks.handlestanza; + function session.dispatch_stanza(session, stanza) + return handlestanza(session, stanza); + end + + local conn = session.conn; + add_task(connect_timeout, function () + if session.conn ~= conn or session.connecting + or session.type == "s2sin" or session.type == "s2sout" then + return; -- Ok, we're connect[ed|ing] + end + -- Not connected, need to close session and clean up + (session.log or log)("debug", "Destroying incomplete session %s->%s due to inactivity", + session.from_host or "(unknown)", session.to_host or "(unknown)"); + session:close("connection-timeout"); + end); +end + +function listener.onconnect(conn) + if not sessions[conn] then -- May be an existing outgoing session + local session = s2s_new_incoming(conn); + sessions[conn] = session; + session.log("debug", "Incoming s2s connection"); + + local filter = initialize_filters(session); + local w = conn.write; + 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 + + initialize_session(session); + end +end + +function listener.onincoming(conn, data) + local session = sessions[conn]; + if session then + session.data(data); + end +end + +function listener.onstatus(conn, status) + if status == "ssl-handshake-complete" then + local session = sessions[conn]; + if session and session.direction == "outgoing" then + local to_host, from_host = session.to_host, session.from_host; + session.log("debug", "Sending stream header..."); + session:open_stream(session.from_host, session.to_host); + end + end +end + +function listener.ondisconnect(conn, err) + local session = sessions[conn]; + if session then + if stream_callbacks.streamdisconnected(session, err) then + return; -- Connection lives, for now + end + end + sessions[conn] = nil; +end + +function listener.register_outgoing(conn, session) + session.direction = "outgoing"; + sessions[conn] = session; + initialize_session(session); +end + +s2sout.set_listener(listener); + +require "core.portmanager".register_service("s2s", { + listener = listener; + default_port = 5269; + encryption = "starttls"; +}); + diff --git a/plugins/s2s/s2sout.lib.lua b/plugins/s2s/s2sout.lib.lua new file mode 100644 index 00000000..094126e7 --- /dev/null +++ b/plugins/s2s/s2sout.lib.lua @@ -0,0 +1,314 @@ +-- Prosody IM +-- 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. +-- + +--- Module containing all the logic for connecting to a remote server + +local initialize_filters = require "util.filters".initialize; +local idna_to_ascii = require "util.encodings".idna.to_ascii; +local add_task = require "util.timer".add_task; +local socket = require "socket"; + +local s2s_destroy_session = require "core.s2smanager".destroy_session; + +local s2sout = {}; + +local s2s_listener; + +function s2sout.set_listener(listener) + s2s_listener = listener; +end + +local function compare_srv_priorities(a,b) + return a.priority < b.priority or (a.priority == b.priority and a.weight > b.weight); +end + +local 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 s2sout.initiate_connection(host_session) + initialize_filters(host_session); + session.open_stream = session_open_stream; + + -- Kick the connection attempting machine into life + if not s2sout.attempt_connection(host_session) then + -- Intentionally not returning here, the + -- session is needed, connected or not + s2s_destroy_session(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 +end + +function s2sout.attempt_connection(host_session, err) + local from_host, to_host = host_session.from_host, host_session.to_host; + local connect_host, connect_port = to_host and idna_to_ascii(to_host), 5269; + + if not connect_host then + return false; + end + + if not err then -- This is our first attempt + 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 + if #srv_hosts == 1 and srv_hosts[1].target == "." then + log("debug", to_host.." does not provide a XMPP service"); + s2s_destroy_session(host_session, err); -- Nothing to see here + return; + 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 + -- Try with SRV, or just the plain hostname if no SRV + local ok, err = s2sout.try_connect(host_session, connect_host, connect_port); + if not ok then + if not s2sout.attempt_connection(host_session, err) then + -- No more attempts will be made + s2s_destroy_session(host_session, err); + end + end + end, "_xmpp-server._tcp."..connect_host..".", "SRV"); + + return true; -- Attempt in progress + elseif host_session.ip_hosts then + return s2sout.try_connect(host_session, connect_host, connect_port, err); + 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("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("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 s2sout.try_connect(host_session, connect_host, connect_port); +end + +function s2sout.try_next_ip(host_session) + host_session.connecting = nil; + host_session.ip_choice = host_session.ip_choice + 1; + local ip = host_session.ip_hosts[host_session.ip_choice]; + local ok, err= s2sout.make_connect(host_session, ip.ip, ip.port); + if not ok then + if not s2sout.attempt_connection(host_session, err or "closed") then + err = err and (": "..err) or ""; + s2s_destroy_session(host_session, "Connection failed"..err); + end + end +end + +function s2sout.try_connect(host_session, connect_host, connect_port, err) + host_session.connecting = true; + + if not err then + local IPs = {}; + host_session.ip_hosts = IPs; + local handle4, handle6; + local has_other = false; + + if not sources then + sources = {}; + for i, source in ipairs(cfg_sources) do + if source == "*" then + sources[i] = new_ip("0.0.0.0", "IPv4"); + else + sources[i] = new_ip(source, (source:find(":") and "IPv6") or "IPv4"); + end + end + end + + handle4 = adns.lookup(function (reply, err) + handle4 = 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 + for _, ip in ipairs(reply) do + log("debug", "DNS reply for %s gives us %s", connect_host, ip.a); + IPs[#IPs+1] = new_ip(ip.a, "IPv4"); + end + end + + if has_other then + if #IPs > 0 then + rfc3484_dest(host_session.ip_hosts, sources); + for i = 1, #IPs do + IPs[i] = {ip = IPs[i], port = connect_port}; + end + host_session.ip_choice = 0; + s2sout.try_next_ip(host_session); + else + log("debug", "DNS lookup failed to get a response for %s", connect_host); + host_session.ip_hosts = nil; + if not s2sout.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); + err = err and (": "..err) or ""; + s2s_destroy_session(host_session, "DNS resolution failed"..err); -- End of the line, we can't + end + end + else + has_other = true; + end + end, connect_host, "A", "IN"); + + handle6 = adns.lookup(function (reply, err) + handle6 = nil; + + if reply and reply[#reply] and reply[#reply].aaaa then + for _, ip in ipairs(reply) do + log("debug", "DNS reply for %s gives us %s", connect_host, ip.aaaa); + IPs[#IPs+1] = new_ip(ip.aaaa, "IPv6"); + end + end + + if has_other then + if #IPs > 0 then + rfc3484_dest(host_session.ip_hosts, sources); + for i = 1, #IPs do + IPs[i] = {ip = IPs[i], port = connect_port}; + end + host_session.ip_choice = 0; + s2sout.try_next_ip(host_session); + else + log("debug", "DNS lookup failed to get a response for %s", connect_host); + host_session.ip_hosts = nil; + if not s2sout.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); + err = err and (": "..err) or ""; + s2s_destroy_session(host_session, "DNS resolution failed"..err); -- End of the line, we can't + end + end + else + has_other = true; + end + end, connect_host, "AAAA", "IN"); + + return true; + elseif host_session.ip_hosts and #host_session.ip_hosts > host_session.ip_choice then -- Not our first attempt, and we also have IPs left to try + s2sout.try_next_ip(host_session); + else + host_session.ip_hosts = nil; + if not s2sout.attempt_connection(host_session, "out of IP addresses") then -- Retry if we can + log("debug", "No other records to try for %s - destroying", host_session.to_host); + err = err and (": "..err) or ""; + s2s_destroy_session(host_session, "Connecting failed"..err); -- End of the line, we can't + return false; + end + end + + return true; +end + +function s2sout.make_connect(host_session, connect_host, connect_port) + (host_session.log or log)("info", "Beginning new connection attempt to %s ([%s]:%d)", host_session.to_host, connect_host.addr, 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; + if connect_host.proto == "IPv4" then + conn, handler = socket.tcp(); + else + conn, handler = socket.tcp6(); + end + + 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.addr, connect_port); + if not success and err ~= "timeout" then + log("warn", "s2s connect() to %s (%s:%d) failed: %s", host_session.to_host, connect_host.addr, connect_port, err); + return false, err; + end + + conn = wrapclient(conn, connect_host.addr, connect_port, s2s_listener, "*a"); + 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 + s2s_listener.register_outgoing(conn, host_session); + + host_session:open_stream(from_host, to_host); + + log("debug", "Connection attempt in progress..."); + return true; +end + +return s2sout; -- cgit v1.2.3