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plugins/mod_s2s.lua @ 11200:bf8f2da84007
Merge 0.11->trunk
author | Kim Alvefur <zash@zash.se> |
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date | Thu, 05 Nov 2020 22:31:25 +0100 |
parent | 11118:plugins/mod_s2s/mod_s2s.lua@ece430d49809 |
parent | 11120:plugins/mod_s2s/mod_s2s.lua@b2331f3dfeea |
child | 11227:d36e44d00ef8 |
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-- 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 prosody = prosody; local hosts = prosody.hosts; local core_process_stanza = prosody.core_process_stanza; local tostring, type = tostring, type; local t_insert = table.insert; local traceback = debug.traceback; local add_task = require "util.timer".add_task; local st = require "util.stanza"; local initialize_filters = require "util.filters".initialize; local nameprep = require "util.encodings".stringprep.nameprep; 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 uuid_gen = require "util.uuid".generate; local fire_global_event = prosody.events.fire_event; local runner = require "util.async".runner; local connect = require "net.connect".connect; local service = require "net.resolvers.service"; local errors = require "util.error"; local set = require "util.set"; local connect_timeout = module:get_option_number("s2s_timeout", 90); local stream_close_timeout = module:get_option_number("s2s_close_timeout", 5); local opt_keepalives = module:get_option_boolean("s2s_tcp_keepalives", module:get_option_boolean("tcp_keepalives", true)); local secure_auth = module:get_option_boolean("s2s_secure_auth", false); -- One day... local secure_domains, insecure_domains = module:get_option_set("s2s_secure_domains", {})._items, module:get_option_set("s2s_insecure_domains", {})._items; local require_encryption = module:get_option_boolean("s2s_require_encryption", false); local stanza_size_limit = module:get_option_number("s2s_stanza_size_limit"); -- TODO come up with a sensible default (util.xmppstream defaults to 10M) local measure_connections = module:measure("connections", "amount"); local measure_ipv6 = module:measure("ipv6", "amount"); local sessions = module:shared("sessions"); local runner_callbacks = {}; local listener = {}; local log = module._log; local s2s_service_options = { default_port = 5269; use_ipv4 = module:get_option_boolean("use_ipv4", true); use_ipv6 = module:get_option_boolean("use_ipv6", true); }; module:hook("stats-update", function () local count = 0; local ipv6 = 0; for _, session in pairs(sessions) do count = count + 1; if session.ip and session.ip:match(":") then ipv6 = ipv6 + 1; end end measure_connections(count); measure_ipv6(ipv6); end); --- 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 %d queued stanzas because of failed outgoing connection to %s", #sendq, session.to_host); local dummy = { type = "s2sin"; send = function () (session.log or log)("error", "Replying to to an s2s error reply, please report this! Traceback: %s", traceback()); end; dummy = true; close = function () (session.log or log)("error", "Attempting to close the dummy origin of s2s error replies, please report this! Traceback: %s", traceback()); end; }; -- FIXME Allow for more specific error conditions -- TODO use util.error ? local error_type = "cancel"; local condition = "remote-server-not-found"; local reason_text; if session.had_stream then -- set when a stream is opened by the remote error_type, condition = "wait", "remote-server-timeout"; end if errors.is_err(reason) then error_type, condition, reason_text = reason.type, reason.condition, reason.text; elseif type(reason) == "string" then reason_text = reason; end 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 = error_type, by = session.from_host}) :tag(condition, {xmlns = "urn:ietf:params:xml:ns:xmpp-stanzas"}):up(); if reason_text then reply:tag("text", {xmlns = "urn:ietf:params:xml:ns:xmpp-stanzas"}) :text("Server-to-server connection failed: "..reason_text):up(); end core_process_stanza(dummy, reply); end sendq[i] = nil; end session.sendq = nil; end -- Handles stanzas to existing s2s sessions function route_to_existing_session(event) local from_host, to_host, stanza = event.from_host, event.to_host, event.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 if hosts[to_host] then log("warn", "Attempt to route stanza to a remote %s - a host we do serve?!", from_host); return false; end local host = hosts[from_host].s2sout[to_host]; if not host then return end -- 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 local queued_item = { tostring(stanza), stanza.attr.type ~= "error" and stanza.attr.type ~= "result" and st.reply(stanza); }; if host.sendq then t_insert(host.sendq, queued_item); else -- luacheck: ignore 122 host.sendq = { queued_item }; end host.log("debug", "stanza [%s] queued ", stanza.name); return true; elseif host.type == "local" or host.type == "component" then log("error", "Trying to send a stanza to ourselves??") log("error", "Traceback: %s", traceback()); log("error", "Stanza: %s", stanza); return false; else if host.sends2s(stanza) then return true; end end end -- Create a new outgoing session for a stanza function route_to_new_session(event) local from_host, to_host, stanza = event.from_host, event.to_host, event.stanza; log("debug", "opening a new outgoing connection for this stanza"); local host_session = s2s_new_outgoing(from_host, to_host); host_session.version = 1; -- 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", stanza.name); connect(service.new(to_host, "xmpp-server", "tcp", s2s_service_options), listener, nil, { session = host_session }); return true; end local function keepalive(event) return event.session.sends2s(' '); end module:hook("s2s-read-timeout", keepalive, -1); function module.add_host(module) if module:get_option_boolean("disallow_s2s", false) then module:log("warn", "The 'disallow_s2s' config option is deprecated, please see https://prosody.im/doc/s2s#disabling"); return nil, "This host has disallow_s2s set"; end module:hook("route/remote", route_to_existing_session, -1); module:hook("route/remote", route_to_new_session, -10); module:hook("s2s-authenticated", make_authenticated, -1); module:hook("s2s-read-timeout", keepalive, -1); module:hook_stanza("http://etherx.jabber.org/streams", "features", function (session, stanza) -- luacheck: ignore 212/stanza if session.type == "s2sout" then -- Stream is authenticated and we are seem to be done with feature negotiation, -- so the stream is ready for stanzas. RFC 6120 Section 4.3 mark_connected(session); return true; elseif require_encryption and not session.secure then session.log("warn", "Encrypted server-to-server communication is required but was not offered by %s", session.to_host); session:close({ condition = "policy-violation", text = "Encrypted server-to-server communication is required but was not offered", }, nil, "Could not establish encrypted connection to remote server"); return true; elseif not session.dialback_verifying then session.log("warn", "No SASL EXTERNAL offer and Dialback doesn't seem to be enabled, giving up"); session:close({ condition = "unsupported-feature", text = "No viable authentication method offered", }, nil, "No viable authentication method offered by remote server"); return true; end end, -1); end -- Stream is authorised, and ready for normal stanzas function mark_connected(session) local sendq = session.sendq; local from, to = session.from_host, session.to_host; session.log("info", "%s s2s connection %s->%s complete", session.direction:gsub("^.", string.upper), from, to); local event_data = { session = session }; if session.type == "s2sout" then fire_global_event("s2sout-established", event_data); hosts[from].events.fire_event("s2sout-established", event_data); if session.incoming then session.send = function(stanza) return hosts[from].events.fire_event("route/remote", { from_host = from, to_host = to, stanza = stanza }); end; end else if session.outgoing and not hosts[to].s2sout[from] then session.log("debug", "Setting up to handle route from %s to %s", to, from); hosts[to].s2sout[from] = session; -- luacheck: ignore 122 end local host_session = hosts[to]; session.send = function(stanza) return host_session.events.fire_event("route/remote", { from_host = to, to_host = from, stanza = stanza }); end; fire_global_event("s2sin-established", event_data); hosts[to].events.fire_event("s2sin-established", event_data); end if session.direction == "outgoing" then if sendq then session.log("debug", "sending %d queued stanzas across new outgoing connection to %s", #sendq, session.to_host); local send = session.sends2s; for i, data in ipairs(sendq) do send(data[1]); sendq[i] = nil; end session.sendq = nil; end end end function make_authenticated(event) local session, host = event.session, event.host; if not session.secure then if require_encryption or (secure_auth and not(insecure_domains[host])) or secure_domains[host] then session:close({ condition = "policy-violation", text = "Encrypted server-to-server communication is required but was not " ..((session.direction == "outgoing" and "offered") or "used") }, nil, "Could not establish encrypted connection to remote server"); end end if hosts[host] then session:close({ condition = "undefined-condition", text = "Attempt to authenticate as a host we serve" }); end if session.type == "s2sout_unauthed" then session.type = "s2sout"; elseif session.type == "s2sin_unauthed" then session.type = "s2sin"; elseif session.type ~= "s2sin" and session.type ~= "s2sout" then return false; end if session.incoming and host then if not session.hosts[host] then session.hosts[host] = {}; end session.hosts[host].authed = true; end session.log("debug", "connection %s->%s is now authenticated for %s", session.from_host, session.to_host, host); if (session.type == "s2sout" and session.external_auth ~= "succeeded") or session.type == "s2sin" then -- Stream either used dialback for authentication or is an incoming stream. mark_connected(session); end return true; end --- Helper to check that a session peer's certificate is valid function check_cert_status(session) local host = session.direction == "outgoing" and session.to_host or session.from_host local conn = session.conn:socket() local cert if conn.getpeercertificate then cert = conn:getpeercertificate() end return module:fire_event("s2s-check-certificate", { host = host, session = session, cert = cert }); end --- XMPP stream event handlers local stream_callbacks = { default_ns = "jabber:server" }; function stream_callbacks.handlestanza(session, stanza) stanza = session.filter("stanzas/in", stanza); session.thread:run(stanza); end local xmlns_xmpp_streams = "urn:ietf:params:xml:ns:xmpp-streams"; function stream_callbacks.streamopened(session, attr) -- run _streamopened in async context session.thread:run({ stream = "opened", attr = attr }); end function stream_callbacks._streamopened(session, attr) session.version = tonumber(attr.version) or 0; session.had_stream = true; -- Had a stream opened at least once -- TODO: Rename session.secure to session.encrypted if session.secure == false then session.secure = true; session.encrypted = true; local sock = session.conn:socket(); if sock.info then local info = sock:info(); (session.log or log)("info", "Stream encrypted (%s with %s)", info.protocol, info.cipher); session.compressed = info.compression; else (session.log or log)("info", "Stream encrypted"); end end if session.direction == "incoming" then -- Send a reply stream header -- Validate to/from local to, from = attr.to, attr.from; if to then to = nameprep(attr.to); end if from then from = nameprep(attr.from); end if not to and attr.to then -- COMPAT: Some servers do not reliably set 'to' (especially on stream restarts) session:close({ condition = "improper-addressing", text = "Invalid 'to' address" }); return; end if not from and attr.from then -- COMPAT: Some servers do not reliably set 'from' (especially on stream restarts) session:close({ condition = "improper-addressing", text = "Invalid 'from' address" }); return; end -- Set session.[from/to]_host if they have not been set already and if -- this session isn't already authenticated if session.type == "s2sin_unauthed" and from and not session.from_host then session.from_host = from; elseif from ~= session.from_host then session:close({ condition = "improper-addressing", text = "New stream 'from' attribute does not match original" }); return; end if session.type == "s2sin_unauthed" and to and not session.to_host then session.to_host = to; elseif to ~= session.to_host then session:close({ condition = "improper-addressing", text = "New stream 'to' attribute does not match original" }); return; end -- For convenience we'll put the sanitised values into these variables to, from = session.to_host, session.from_host; session.streamid = uuid_gen(); (session.log or log)("debug", "Incoming s2s received %s", st.stanza("stream:stream", attr):top_tag()); if to then if not hosts[to] then -- Attempting to connect to a host we don't serve session:close({ condition = "host-unknown"; text = "This host does not serve "..to }); return; elseif not hosts[to].modules.s2s then -- Attempting to connect to a host that disallows s2s session:close({ condition = "policy-violation"; text = "Server-to-server communication is disabled for this host"; }); return; end end if hosts[from] then session:close({ condition = "undefined-condition", text = "Attempt to connect from a host we serve" }); return; end if session.secure and not session.cert_chain_status then if check_cert_status(session) == false then return; end end session:open_stream(session.to_host, session.from_host) session.notopen = nil; if session.version >= 1.0 then local features = st.stanza("stream:features"); if to then hosts[to].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", from or session.ip or "unknown host"); fire_global_event("s2s-stream-features-legacy", { origin = session, features = features }); end if ( session.type == "s2sin" or session.type == "s2sout" ) or features.tags[1] then log("debug", "Sending stream features: %s", features); session.sends2s(features); else (session.log or log)("warn", "No stream features to offer, giving up"); session:close({ condition = "undefined-condition", text = "No stream features to offer" }); end end elseif session.direction == "outgoing" then session.notopen = nil; if not attr.id then log("warn", "Stream response did not give us a stream id!"); session:close({ condition = "undefined-condition", text = "Missing stream ID" }); return; end session.streamid = attr.id; if session.secure and not session.cert_chain_status then if check_cert_status(session) == false then return; end end -- 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 hosts[session.from_host].events.fire_event("s2sout-authenticate-legacy", { origin = session }); else mark_connected(session); end end end end function stream_callbacks._streamclosed(session) (session.log or log)("debug", "Received </stream:stream>"); session:close(false); end function stream_callbacks.streamclosed(session, attr) -- run _streamclosed in async context session.thread:run({ stream = "closed", attr = attr }); end function stream_callbacks.error(session, error, data) if error == "no-stream" then session.log("debug", "Invalid opening stream header (%s)", (data:gsub("^([^\1]+)\1", "{%1}"))); session:close("invalid-namespace"); elseif error == "parse-error" then session.log("debug", "Server-to-server XML parse error: %s", error); session:close("not-well-formed"); elseif error == "stream-error" then local condition, text = "undefined-condition"; for child in data:childtags(nil, xmlns_xmpp_streams) do if child.name ~= "text" then condition = child.name; else text = child:get_text(); end if condition ~= "undefined-condition" and text then break; 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 --- Session methods local stream_xmlns_attr = {xmlns='urn:ietf:params:xml:ns:xmpp-streams'}; -- reason: stream error to send to the remote server -- remote_reason: stream error received from the remote server -- bounce_reason: stanza error to pass to bounce_sendq because stream- and stanza errors are different local function session_close(session, reason, remote_reason, bounce_reason) local log = session.log or log; if session.conn then if session.notopen then if session.direction == "incoming" then session:open_stream(session.to_host, session.from_host); else session:open_stream(session.from_host, session.to_host); end end if reason then -- nil == no err, initiated by us, false == initiated by remote local stream_error; if type(reason) == "string" then -- assume stream error stream_error = st.stanza("stream:error"):tag(reason, {xmlns = 'urn:ietf:params:xml:ns:xmpp-streams' }); elseif type(reason) == "table" and not st.is_stanza(reason) then stream_error = st.stanza("stream:error"):tag(reason.condition or "undefined-condition", stream_xmlns_attr):up(); if reason.text then stream_error:tag("text", stream_xmlns_attr):text(reason.text):up(); end if reason.extra then stream_error:add_child(reason.extra); end end if st.is_stanza(stream_error) then -- to and from are never unknown on outgoing connections log("debug", "Disconnecting %s->%s[%s], <stream:error> is: %s", session.from_host or "(unknown host)" or session.ip, session.to_host or "(unknown host)", session.type, reason); session.sends2s(stream_error); end end session.sends2s("</stream:stream>"); function session.sends2s() return false; end -- luacheck: ignore 422/reason -- FIXME reason should be managed in a place common to c2s, s2s, bosh, component etc local reason = remote_reason or (reason and (reason.text or reason.condition)) or reason; session.log("info", "%s s2s stream %s->%s closed: %s", session.direction:gsub("^.", string.upper), session.from_host or "(unknown host)", session.to_host or "(unknown host)", reason or "stream closed"); -- Authenticated incoming stream may still be sending us stanzas, so wait for </stream:stream> from remote local conn = session.conn; if reason == nil and not session.notopen and session.incoming then add_task(stream_close_timeout, function () if not session.destroyed then session.log("warn", "Failed to receive a stream close response, closing connection anyway..."); s2s_destroy_session(session, reason, bounce_reason); conn:close(); end end); else s2s_destroy_session(session, reason, bounce_reason); conn:close(); -- Close immediately, as this is an outgoing connection or is not authed end end end function session_stream_attrs(session, from, to, attr) -- luacheck: ignore 212/session if not from or (hosts[from] and hosts[from].modules.dialback) then attr["xmlns:db"] = 'jabber:server:dialback'; end if not from then attr.from = ''; end if not to then attr.to = ''; end end -- Session initialization logic shared by incoming and outgoing local function initialize_session(session) local stream = new_xmpp_stream(session, stream_callbacks, stanza_size_limit); session.thread = runner(function (stanza) if st.is_stanza(stanza) then core_process_stanza(session, stanza); elseif stanza.stream == "opened" then stream_callbacks._streamopened(session, stanza.attr); elseif stanza.stream == "closed" then stream_callbacks._streamclosed(session, stanza.attr); end end, runner_callbacks, session); local log = session.log or log; session.stream = stream; session.notopen = true; function session.reset_stream() session.notopen = true; session.streamid = nil; session.stream:reset(); end session.stream_attrs = session_stream_attrs; local filter = initialize_filters(session); local conn = session.conn; local w = conn.write; function session.sends2s(t) log("debug", "Sending[%s]: %s", session.type, 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 function session.data(data) data = filter("bytes/in", data); if data then local ok, err = stream:feed(data); if ok then return; end log("debug", "Received invalid XML (%s) %d bytes: %q", err, #data, data:sub(1, 300)); if err == "stanza-too-large" then session:close({ condition = "policy-violation", text = "XML stanza is too big" }, nil, "Received invalid XML from remote server"); else session:close("not-well-formed", nil, "Received invalid XML from remote server"); end end end session.close = session_close; local handlestanza = stream_callbacks.handlestanza; function session.dispatch_stanza(session, stanza) -- luacheck: ignore 432/session return handlestanza(session, stanza); end module:fire_event("s2s-created", { session = session }); add_task(connect_timeout, function () if session.type == "s2sin" or session.type == "s2sout" then return; -- Ok, we're connected elseif session.type == "s2s_destroyed" then return; -- Session already destroyed 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 runner_callbacks:ready() self.data.log("debug", "Runner %s ready (%s)", self.thread, coroutine.status(self.thread)); self.data.conn:resume(); end function runner_callbacks:waiting() self.data.log("debug", "Runner %s waiting (%s)", self.thread, coroutine.status(self.thread)); self.data.conn:pause(); end function runner_callbacks:error(err) (self.data.log or log)("error", "Traceback[s2s]: %s", err); end function listener.onconnect(conn) conn:setoption("keepalive", opt_keepalives); local session = sessions[conn]; if not session then -- New incoming connection session = s2s_new_incoming(conn); sessions[conn] = session; session.log("debug", "Incoming s2s connection"); initialize_session(session); else -- Outgoing session connected session:open_stream(session.from_host, session.to_host); end session.ip = conn:ip(); 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 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 sessions[conn] = nil; (session.log or log)("debug", "s2s disconnected: %s->%s (%s)", session.from_host, session.to_host, err or "connection closed"); if session.secure == false and err then -- TODO util.error-ify this err = "Error during negotiation of encrypted connection: "..err; end s2s_destroy_session(session, err); end end function listener.onfail(data, err) local session = data and data.session; if session then if err and session.direction == "outgoing" and session.notopen then (session.log or log)("debug", "s2s connection attempt failed: %s", err); end (session.log or log)("debug", "s2s disconnected: %s->%s (%s)", session.from_host, session.to_host, err or "connection closed"); s2s_destroy_session(session, err); end end function listener.onreadtimeout(conn) local session = sessions[conn]; if session then local host = session.host or session.to_host; return (hosts[host] or prosody).events.fire_event("s2s-read-timeout", { session = session }); end end function listener.register_outgoing(conn, session) sessions[conn] = session; initialize_session(session); end function listener.ondetach(conn) sessions[conn] = nil; end function listener.onattach(conn, data) local session = data and data.session; if session then session.conn = conn; sessions[conn] = session; initialize_session(session); end end -- Complete the sentence "Your certificate " with what's wrong local function friendly_cert_error(session) --> string if session.cert_chain_status == "invalid" then if session.cert_chain_errors then local cert_errors = set.new(session.cert_chain_errors[1]); if cert_errors:contains("certificate has expired") then return "has expired"; elseif cert_errors:contains("self signed certificate") then return "is self-signed"; end end return "is not trusted"; -- for some other reason elseif session.cert_identity_status == "invalid" then return "is not valid for this name"; end -- this should normally be unreachable except if no s2s auth module was loaded return "could not be validated"; end function check_auth_policy(event) local host, session = event.host, event.session; local must_secure = secure_auth; if not must_secure and secure_domains[host] then must_secure = true; elseif must_secure and insecure_domains[host] then must_secure = false; end if must_secure and (session.cert_chain_status ~= "valid" or session.cert_identity_status ~= "valid") then local reason = friendly_cert_error(session); session.log("warn", "Forbidding insecure connection to/from %s because its certificate %s", host or session.ip or "(unknown host)", reason); -- XEP-0178 recommends closing outgoing connections without warning -- but does not give a rationale for this. -- In practice most cases are configuration mistakes or forgotten -- certificate renewals. We think it's better to let the other party -- know about the problem so that they can fix it. session:close({ condition = "not-authorized", text = "Your server's certificate "..reason }, nil, "Remote server's certificate "..reason); return false; end end module:hook("s2s-check-certificate", check_auth_policy, -1); module:hook("server-stopping", function(event) local reason = event.reason; for _, session in pairs(sessions) do session:close{ condition = "system-shutdown", text = reason }; end end, -200); module:provides("net", { name = "s2s"; listener = listener; default_port = 5269; encryption = "starttls"; ssl_config = { -- FIXME This is not used atm, see mod_tls verify = { "peer", "client_once", }; }; multiplex = { protocol = "xmpp-server"; pattern = "^<.*:stream.*%sxmlns%s*=%s*(['\"])jabber:server%1.*>"; }; });