-- 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(); -- Global module local hosts = _G.hosts; local new_xmpp_stream = require "util.xmppstream".new; local sm = require "core.sessionmanager"; local sm_destroy_session = sm.destroy_session; local new_uuid = require "util.uuid".generate; local core_process_stanza = prosody.core_process_stanza; local st = require "util.stanza"; local logger = require "util.logger"; local log = logger.init("mod_bosh"); local initialize_filters = require "util.filters".initialize; local math_min = math.min; local xpcall, tostring, type = xpcall, tostring, type; local traceback = debug.traceback; local nameprep = require "util.encodings".stringprep.nameprep; local xmlns_streams = "http://etherx.jabber.org/streams"; local xmlns_xmpp_streams = "urn:ietf:params:xml:ns:xmpp-streams"; local xmlns_bosh = "http://jabber.org/protocol/httpbind"; -- (hard-coded into a literal in session.send) local stream_callbacks = { stream_ns = xmlns_bosh, stream_tag = "body", default_ns = "jabber:client" }; local BOSH_DEFAULT_HOLD = module:get_option_number("bosh_default_hold", 1); local BOSH_DEFAULT_INACTIVITY = module:get_option_number("bosh_max_inactivity", 60); local BOSH_DEFAULT_POLLING = module:get_option_number("bosh_max_polling", 5); local BOSH_DEFAULT_REQUESTS = module:get_option_number("bosh_max_requests", 2); local bosh_max_wait = module:get_option_number("bosh_max_wait", 120); local consider_bosh_secure = module:get_option_boolean("consider_bosh_secure"); local cross_domain = module:get_option("cross_domain_bosh", false); if cross_domain == true then cross_domain = "*"; end if type(cross_domain) == "table" then cross_domain = table.concat(cross_domain, ", "); end local trusted_proxies = module:get_option_set("trusted_proxies", {"127.0.0.1"})._items; local function get_ip_from_request(request) local ip = request.conn:ip(); local forwarded_for = request.headers.x_forwarded_for; if forwarded_for then forwarded_for = forwarded_for..", "..ip; for forwarded_ip in forwarded_for:gmatch("[^%s,]+") do if not trusted_proxies[forwarded_ip] then ip = forwarded_ip; end end end return ip; end local t_insert, t_remove, t_concat = table.insert, table.remove, table.concat; local os_time = os.time; -- All sessions, and sessions that have no requests open local sessions, inactive_sessions = module:shared("sessions", "inactive_sessions"); -- Used to respond to idle sessions (those with waiting requests) local waiting_requests = module:shared("waiting_requests"); function on_destroy_request(request) log("debug", "Request destroyed: %s", tostring(request)); waiting_requests[request] = nil; local session = sessions[request.context.sid]; if session then local requests = session.requests; for i, r in ipairs(requests) do if r == request then t_remove(requests, i); break; end end -- If this session now has no requests open, mark it as inactive local max_inactive = session.bosh_max_inactive; if max_inactive and #requests == 0 then inactive_sessions[session] = os_time() + max_inactive; (session.log or log)("debug", "BOSH session marked as inactive (for %ds)", max_inactive); end end end local function set_cross_domain_headers(response) local headers = response.headers; headers.access_control_allow_methods = "GET, POST, OPTIONS"; headers.access_control_allow_headers = "Content-Type"; headers.access_control_max_age = "7200"; headers.access_control_allow_origin = cross_domain; return response; end function handle_OPTIONS(event) if cross_domain and event.request.headers.origin then set_cross_domain_headers(event.response); end return ""; end function handle_POST(event) log("debug", "Handling new request %s: %s\n----------", tostring(event.request), tostring(event.request.body)); local request, response = event.request, event.response; response.on_destroy = on_destroy_request; local body = request.body; local context = { request = request, response = response, notopen = true }; local stream = new_xmpp_stream(context, stream_callbacks); response.context = context; local headers = response.headers; headers.content_type = "text/xml; charset=utf-8"; if cross_domain and event.request.headers.origin then set_cross_domain_headers(response); end -- stream:feed() calls the stream_callbacks, so all stanzas in -- the body are processed in this next line before it returns. -- In particular, the streamopened() stream callback is where -- much of the session logic happens, because it's where we first -- get to see the 'sid' of this request. local ok, err = stream:feed(body); if not ok then module:log("warn", "Error parsing BOSH payload; %s", err) local close_reply = st.stanza("body", { xmlns = xmlns_bosh, type = "terminate", ["xmlns:stream"] = xmlns_streams, condition = "bad-request" }); return tostring(close_reply); end -- Stanzas (if any) in the request have now been processed, and -- we take care of the high-level BOSH logic here, including -- giving a response or putting the request "on hold". local session = sessions[context.sid]; if session then -- Session was marked as inactive, since we have -- a request open now, unmark it if inactive_sessions[session] and #session.requests > 0 then inactive_sessions[session] = nil; end local r = session.requests; log("debug", "Session %s has %d out of %d requests open", context.sid, #r, session.bosh_hold); log("debug", "and there are %d things in the send_buffer:", #session.send_buffer); if #r > session.bosh_hold then -- We are holding too many requests, send what's in the buffer, log("debug", "We are holding too many requests, so..."); if #session.send_buffer > 0 then log("debug", "...sending what is in the buffer") session.send(t_concat(session.send_buffer)); session.send_buffer = {}; else -- or an empty response log("debug", "...sending an empty response"); session.send(""); end elseif #session.send_buffer > 0 then log("debug", "Session has data in the send buffer, will send now.."); local resp = t_concat(session.send_buffer); session.send_buffer = {}; session.send(resp); end if not response.finished then -- We're keeping this request open, to respond later log("debug", "Have nothing to say, so leaving request unanswered for now"); if session.bosh_wait then waiting_requests[response] = os_time() + session.bosh_wait; end end if session.bosh_terminate then session.log("debug", "Closing session with %d requests open", #session.requests); session:close(); return nil; else return true; -- Inform http server we shall reply later end elseif response.finished then return; -- A response has been sent already end module:log("warn", "Unable to associate request with a session (incomplete request?)"); local close_reply = st.stanza("body", { xmlns = xmlns_bosh, type = "terminate", ["xmlns:stream"] = xmlns_streams, condition = "item-not-found" }); return tostring(close_reply) .. "\n"; end local function bosh_reset_stream(session) session.notopen = true; end local stream_xmlns_attr = { xmlns = "urn:ietf:params:xml:ns:xmpp-streams" }; local function bosh_close_stream(session, reason) (session.log or log)("info", "BOSH client disconnected"); local close_reply = st.stanza("body", { xmlns = xmlns_bosh, type = "terminate", ["xmlns:stream"] = xmlns_streams }); if reason then close_reply.attr.condition = "remote-stream-error"; if type(reason) == "string" then -- assume stream error close_reply:tag("stream:error") :tag(reason, {xmlns = xmlns_xmpp_streams}); elseif type(reason) == "table" then if reason.condition then close_reply:tag("stream:error") :tag(reason.condition, stream_xmlns_attr):up(); if reason.text then close_reply:tag("text", stream_xmlns_attr):text(reason.text):up(); end if reason.extra then close_reply:add_child(reason.extra); end elseif reason.name then -- a stanza close_reply = reason; end end log("info", "Disconnecting client, is: %s", tostring(close_reply)); end local response_body = tostring(close_reply); for _, held_request in ipairs(session.requests) do held_request:send(response_body); end sessions[session.sid] = nil; inactive_sessions[session] = nil; sm_destroy_session(session); end -- Handle the tag in the request payload. function stream_callbacks.streamopened(context, attr) local request, response = context.request, context.response; local sid = attr.sid; log("debug", "BOSH body open (sid: %s)", sid or ""); if not sid then -- New session request context.notopen = nil; -- Signals that we accept this opening tag local to_host = nameprep(attr.to); local rid = tonumber(attr.rid); local wait = tonumber(attr.wait); if not to_host then log("debug", "BOSH client tried to connect to invalid host: %s", tostring(attr.to)); local close_reply = st.stanza("body", { xmlns = xmlns_bosh, type = "terminate", ["xmlns:stream"] = xmlns_streams, condition = "improper-addressing" }); response:send(tostring(close_reply)); return; elseif not hosts[to_host] then -- Unknown host log("debug", "BOSH client tried to connect to unknown host: %s", tostring(attr.to)); local close_reply = st.stanza("body", { xmlns = xmlns_bosh, type = "terminate", ["xmlns:stream"] = xmlns_streams, condition = "host-unknown" }); response:send(tostring(close_reply)); return; end if not rid or (not wait and attr.wait or wait < 0 or wait % 1 ~= 0) then log("debug", "BOSH client sent invalid rid or wait attributes: rid=%s, wait=%s", tostring(attr.rid), tostring(attr.wait)); local close_reply = st.stanza("body", { xmlns = xmlns_bosh, type = "terminate", ["xmlns:stream"] = xmlns_streams, condition = "bad-request" }); response:send(tostring(close_reply)); return; end rid = rid - 1; wait = math_min(wait, bosh_max_wait); -- New session sid = new_uuid(); local session = { type = "c2s_unauthed", conn = {}, sid = sid, rid = rid, host = attr.to, bosh_version = attr.ver, bosh_wait = wait, streamid = sid, bosh_hold = BOSH_DEFAULT_HOLD, bosh_max_inactive = BOSH_DEFAULT_INACTIVITY, requests = { }, send_buffer = {}, reset_stream = bosh_reset_stream, close = bosh_close_stream, dispatch_stanza = core_process_stanza, notopen = true, log = logger.init("bosh"..sid), secure = consider_bosh_secure or request.secure, ip = get_ip_from_request(request); }; sessions[sid] = session; local filter = initialize_filters(session); session.log("debug", "BOSH session created for request from %s", session.ip); log("info", "New BOSH session, assigned it sid '%s'", sid); hosts[session.host].events.fire_event("bosh-session", { session = session, request = request }); -- Send creation response local creating_session = true; local r = session.requests; function session.send(s) -- We need to ensure that outgoing stanzas have the jabber:client xmlns if s.attr and not s.attr.xmlns then s = st.clone(s); s.attr.xmlns = "jabber:client"; end s = filter("stanzas/out", s); --log("debug", "Sending BOSH data: %s", tostring(s)); if not s then return true end t_insert(session.send_buffer, tostring(s)); local oldest_request = r[1]; if oldest_request and not session.bosh_processing then log("debug", "We have an open request, so sending on that"); local body_attr = { xmlns = "http://jabber.org/protocol/httpbind", ["xmlns:stream"] = "http://etherx.jabber.org/streams"; type = session.bosh_terminate and "terminate" or nil; sid = sid; }; if creating_session then creating_session = nil; body_attr.inactivity = tostring(BOSH_DEFAULT_INACTIVITY); body_attr.polling = tostring(BOSH_DEFAULT_POLLING); body_attr.requests = tostring(BOSH_DEFAULT_REQUESTS); body_attr.wait = tostring(session.bosh_wait); body_attr.hold = tostring(session.bosh_hold); body_attr.authid = sid; body_attr.secure = "true"; body_attr.ver = '1.6'; body_attr.from = session.host; body_attr["xmlns:xmpp"] = "urn:xmpp:xbosh"; body_attr["xmpp:version"] = "1.0"; end oldest_request:send(st.stanza("body", body_attr):top_tag()..t_concat(session.send_buffer)..""); session.send_buffer = {}; end return true; end request.sid = sid; end local session = sessions[sid]; if not session then -- Unknown sid log("info", "Client tried to use sid '%s' which we don't know about", sid); response:send(tostring(st.stanza("body", { xmlns = xmlns_bosh, type = "terminate", condition = "item-not-found" }))); context.notopen = nil; return; end if session.rid then local rid = tonumber(attr.rid); local diff = rid - session.rid; -- Diff should be 1 for a healthy request if diff ~= 1 then context.sid = sid; context.notopen = nil; if diff == 2 then -- Hold request, but don't process it (ouch!) session.log("debug", "rid skipped: %d, deferring this request", rid-1) context.defer = true; session.bosh_deferred = { context = context, sid = sid, rid = rid, terminate = attr.type == "terminate" }; return; end context.ignore = true; if diff == 0 then -- Re-send previous response, ignore stanzas in this request session.log("debug", "rid repeated, ignoring: %s (diff %d)", session.rid, diff); response:send(session.bosh_last_response); return; end -- Session broken, destroy it session.log("debug", "rid out of range: %d (diff %d)", rid, diff); response:send(tostring(st.stanza("body", { xmlns = xmlns_bosh, type = "terminate", condition = "item-not-found" }))); return; end session.rid = rid; end if attr.type == "terminate" then -- Client wants to end this session, which we'll do -- after processing any stanzas in this request session.bosh_terminate = true; end context.notopen = nil; -- Signals that we accept this opening tag t_insert(session.requests, response); context.sid = sid; session.bosh_processing = true; -- Used to suppress replies until processing of this request is done if session.notopen then local features = st.stanza("stream:features"); hosts[session.host].events.fire_event("stream-features", { origin = session, features = features }); session.send(features); session.notopen = nil; end end local function handleerr(err) log("error", "Traceback[bosh]: %s", traceback(tostring(err), 2)); end function stream_callbacks.handlestanza(context, stanza) if context.ignore then return; end log("debug", "BOSH stanza received: %s\n", stanza:top_tag()); local session = sessions[context.sid]; if session then if stanza.attr.xmlns == xmlns_bosh then stanza.attr.xmlns = nil; end if context.defer and session.bosh_deferred then log("debug", "Deferring this stanza"); t_insert(session.bosh_deferred, stanza); else stanza = session.filter("stanzas/in", stanza); if stanza then return xpcall(function () return core_process_stanza(session, stanza) end, handleerr); end end end end function stream_callbacks.streamclosed(context) local session = sessions[context.sid]; if session then if not context.defer and session.bosh_deferred then -- Handle deferred stanzas now local deferred_stanzas = session.bosh_deferred; local context = deferred_stanzas.context; session.bosh_deferred = nil; log("debug", "Handling deferred stanzas from rid %d", deferred_stanzas.rid); session.rid = deferred_stanzas.rid; t_insert(session.requests, context.response); for _, stanza in ipairs(deferred_stanzas) do stream_callbacks.handlestanza(context, stanza); end if deferred_stanzas.terminate then session.bosh_terminate = true; end end session.bosh_processing = false; if #session.send_buffer > 0 then session.send(""); end end end function stream_callbacks.error(context, error) log("debug", "Error parsing BOSH request payload; %s", error); if not context.sid then local response = context.response; local close_reply = st.stanza("body", { xmlns = xmlns_bosh, type = "terminate", ["xmlns:stream"] = xmlns_streams, condition = "bad-request" }); response:send(tostring(close_reply)); return; end local session = sessions[context.sid]; if error == "stream-error" then -- Remote stream error, we close normally session:close(); else session:close({ condition = "bad-format", text = "Error processing stream" }); end end local dead_sessions = module:shared("dead_sessions"); function on_timer() -- log("debug", "Checking for requests soon to timeout..."); -- Identify requests timing out within the next few seconds local now = os_time() + 3; for request, reply_before in pairs(waiting_requests) do if reply_before <= now then log("debug", "%s was soon to timeout (at %d, now %d), sending empty response", tostring(request), reply_before, now); -- Send empty response to let the -- client know we're still here if request.conn then sessions[request.context.sid].send(""); end end end now = now - 3; local n_dead_sessions = 0; for session, close_after in pairs(inactive_sessions) do if close_after < now then (session.log or log)("debug", "BOSH client inactive too long, destroying session at %d", now); sessions[session.sid] = nil; inactive_sessions[session] = nil; n_dead_sessions = n_dead_sessions + 1; dead_sessions[n_dead_sessions] = session; end end for i=1,n_dead_sessions do local session = dead_sessions[i]; dead_sessions[i] = nil; sm_destroy_session(session, "BOSH client silent for over "..session.bosh_max_inactive.." seconds"); end return 1; end module:add_timer(1, on_timer); local GET_response = { headers = { content_type = "text/html"; }; body = [[

It works! Now point your BOSH client to this URL to connect to Prosody.

For more information see Prosody: Setting up BOSH.

]]; }; function module.add_host(module) module:depends("http"); module:provides("http", { default_path = "/http-bind"; route = { ["GET"] = GET_response; ["GET /"] = GET_response; ["OPTIONS"] = handle_OPTIONS; ["OPTIONS /"] = handle_OPTIONS; ["POST"] = handle_POST; ["POST /"] = handle_POST; }; }); end