--- a/mod_websocket/mod_websocket.lua	Thu May 24 23:52:36 2012 +0200
+++ b/mod_websocket/mod_websocket.lua	Fri May 25 17:20:41 2012 +0200
@@ -1,53 +1,127 @@
-module.host = "*" -- Global module
+-- Prosody IM
+-- Copyright (C) 2008-2010 Matthew Wild
+-- Copyright (C) 2008-2010 Waqas Hussain
+-- Copyright (C) 2012 Florian Zeitz
+--
+-- This project is MIT/X11 licensed. Please see the
+-- COPYING file in the source package for more information.
+--
+
+module:set_global();
 
-local logger = require "util.logger";
-local log = logger.init("mod_websocket");
-local httpserver = require "net.httpserver";
-local lxp = require "lxp";
-local init_xmlhandlers = require "core.xmlhandlers";
+local add_task = require "util.timer".add_task;
+local new_xmpp_stream = require "util.xmppstream".new;
+local nameprep = require "util.encodings".stringprep.nameprep;
+local sessionmanager = require "core.sessionmanager";
 local st = require "util.stanza";
-local sm = require "core.sessionmanager";
+local sm_new_session, sm_destroy_session = sessionmanager.new_session, sessionmanager.destroy_session;
+local uuid_generate = require "util.uuid".generate;
+local sha1 = require "util.hashes".sha1;
+local base64 = require "util.encodings".base64.encode;
+local bxor = require "bit".bxor;
+local tohex = require "bit".tohex;
 
-local sessions = {};
-local default_headers = { };
+module:depends("http")
 
 
-local stream_callbacks = { default_ns = "jabber:client",
-		streamopened = sm.streamopened,
-		streamclosed = sm.streamclosed,
-		handlestanza = core_process_stanza };
+local xpcall, tostring, type = xpcall, tostring, type;
+local traceback = debug.traceback;
+
+local xmlns_xmpp_streams = "urn:ietf:params:xml:ns:xmpp-streams";
+
+local log = module._log;
+
+local c2s_timeout = module:get_option_number("c2s_timeout");
+local opt_keepalives = module:get_option_boolean("tcp_keepalives", false);
+
+local sessions = module:shared("sessions");
+
+local stream_callbacks = { default_ns = "jabber:client", handlestanza = core_process_stanza };
+local listener = {};
+
+--- Stream events handlers
+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 = "" };
+
+function stream_callbacks.streamopened(session, attr)
+	local send = session.send;
+	session.host = nameprep(attr.to);
+	if not session.host then
+		session:close{ condition = "improper-addressing",
+			text = "A valid 'to' attribute is required on stream headers" };
+		return;
+	end
+	session.version = tonumber(attr.version) or 0;
+	session.streamid = uuid_generate();
+	(session.log or session)("debug", "Client sent opening <stream:stream> to %s", session.host);
+
+	if not hosts[session.host] then
+		-- We don't serve this host...
+		session:close{ condition = "host-unknown", text = "This server does not serve "..tostring(session.host)};
+		return;
+	end
+
+	send("<?xml version='1.0'?>"..(tostring(st.stanza("stream:stream", {
+		xmlns = 'jabber:client', ["xmlns:stream"] = 'http://etherx.jabber.org/streams';
+		id = session.streamid, from = session.host, version = '1.0', ["xml:lang"] = 'en' }):top_tag()):gsub(">", "/>")));
+
+	(session.log or log)("debug", "Sent reply <stream:stream> to client");
+	session.notopen = nil;
+
+	-- If session.secure is *false* (not nil) then it means we /were/ encrypting
+	-- since we now have a new stream header, session is secured
+	if session.secure == false then
+		session.secure = true;
+	end
+
+	local features = st.stanza("stream:features");
+	hosts[session.host].events.fire_event("stream-features", { origin = session, features = features });
+	module:fire_event("stream-features", session, features);
+
+	send(features);
+end
+
+function stream_callbacks.streamclosed(session)
+	session.log("debug", "Received </stream:stream>");
+	session:close();
+end
+
 function stream_callbacks.error(session, error, data)
 	if error == "no-stream" then
 		session.log("debug", "Invalid opening stream header");
 		session:close("invalid-namespace");
-	elseif session.close then
-		(session.log or log)("debug", "Client XML parse error: %s", tostring(error));
-		session:close("xml-not-well-formed");
+	elseif error == "parse-error" then
+		(session.log or log)("debug", "Client XML parse error: %s", tostring(data));
+		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 session_reset_stream(session)
-	local parser = lxp.new(init_xmlhandlers(session, stream_callbacks), "\1");
-	session.parser = parser;
-
-	session.notopen = true;
-
-	function session.data(conn, data)
-		data, _ = data:gsub("[%z\255]", "")
-		log("debug", "Parsing: %s", data)
-
-		local ok, err = parser:parse(data)
-		if not ok then
-			log("debug", "Received invalid XML (%s) %d bytes: %s", tostring(err), #data,
-				data:sub(1, 300):gsub("[\r\n]+", " "):gsub("[%z\1-\31]", "_"));
-			session:close("xml-not-well-formed");
-		end
+local function handleerr(err) log("error", "Traceback[c2s]: %s: %s", tostring(err), traceback()); end
+function stream_callbacks.handlestanza(session, stanza)
+	stanza = session.filter("stanzas/in", stanza);
+	if stanza then
+		return xpcall(function () return core_process_stanza(session, stanza) end, handleerr);
 	end
 end
 
-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 = "" };
+--- Session methods
 local function session_close(session, reason)
 	local log = session.log or log;
 	if session.conn then
@@ -78,85 +152,137 @@
 		end
 		session.send("</stream:stream>");
 		session.conn:close();
-		websocket_listener.ondisconnect(session.conn, (reason and (reason.text or reason.condition)) or reason or "session closed");
+		listener.ondisconnect(session.conn, (reason and (reason.text or reason.condition)) or reason or "session closed");
 	end
 end
 
+--- Port listener
+function listener.onconnect(conn)
+	local session = sm_new_session(conn);
+	sessions[conn] = session;
 
-local websocket_listener = { default_mode = "*a" };
-function websocket_listener.onincoming(conn, data)
-	local session = sessions[conn];
-	if not session then
-		session = { type = "c2s_unauthed",
-			conn = conn,
-			reset_stream = session_reset_stream,
-			close = session_close,
-			dispatch_stanza = stream_callbacks.handlestanza,
-			log = logger.init("websocket"),
-			secure = conn.ssl };
+	session.log("info", "Client connected");
+
+	-- Client is using legacy SSL (otherwise mod_tls sets this flag)
+	if conn:ssl() then
+		session.secure = true;
+	end
 
-		function session.send(s)
-			conn:write("\00" .. tostring(s) .. "\255");
-		end
+	if opt_keepalives then
+		conn:setoption("keepalive", opt_keepalives);
+	end
+
+	session.close = session_close;
 
-		sessions[conn] = 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
 
-	session_reset_stream(session);
+	local filter = session.filter;
+	function session.data(data)
+		local off = 0;
+		local len = string.byte(data, 2) - 0x80;
+		if len == 126 then
+			off = 2;
+		elseif len ==127 then
+			off = 8;
+		end
+		local key = {string.byte(data, off+3), string.byte(data, off+4), string.byte(data, off+5), string.byte(data, off+6)}
+		local decoded = "";
+		local counter = 0;
+		for i = off+7, #data do
+			decoded = decoded .. string.char(bxor(key[counter+1], string.byte(data, i)));
+			counter = (counter + 1) % 4;
+		end
+		module:log("debug", "Websocket received: %s %i", decoded, #decoded)
+		decoded = decoded:gsub("/>$", ">");
+
+		data = filter("bytes/in", decoded);
+		if data then
+			local ok, err = stream:feed(data);
+			if ok then return; end
+			log("debug", "Received invalid XML (%s) %d bytes: %s", tostring(err), #data, data:sub(1, 300):gsub("[\r\n]+", " "):gsub("[%z\1-\31]", "_"));
+			session:close("not-well-formed");
+		end
+	end
 
-	if data then
-		session.data(conn, data);
+	function session.send(s)
+		s = tostring(s);
+		local len = #s;
+		if len < 126 then
+			conn:write("\x81" .. string.char(len) .. s);
+		elseif len <= 0xffff then
+			conn:write("\x81" .. string.char(126) .. string.char(len/0x100) .. string.char(len%0x100) .. s);
+		else
+			conn:write("\x81" .. string.char(127) .. string.char(len/0x100000000000000)
+			.. string.char((len%0x100000000000000)/0x1000000000000) .. string.char((len%0x1000000000000)/0x10000000000)
+			.. string.char((len%0x10000000000)/0x100000000) .. string.char((len%0x100000000)/0x1000000)
+			.. string.char((len%0x1000000)/0x10000) .. string.char((len%0x10000)/0x100)
+			.. string.char((len%0x100)))
+		end
+	end
+
+	if c2s_timeout then
+		add_task(c2s_timeout, function ()
+			if session.type == "c2s_unauthed" then
+				session:close("connection-timeout");
+			end
+		end);
+	end
+
+	session.dispatch_stanza = stream_callbacks.handlestanza;
+end
+
+function listener.onincoming(conn, data)
+	local session = sessions[conn];
+	if session then
+		session.data(data);
+	else
+		listener.onconnect(conn, data);
+		session = sessions[conn];
+		session.data(data);
 	end
 end
 
-function websocket_listener.ondisconnect(conn, err)
+function listener.ondisconnect(conn, err)
 	local session = sessions[conn];
 	if session then
 		(session.log or log)("info", "Client disconnected: %s", err);
-		sm.destroy_session(session, err);
-		sessions[conn] = nil;
+		sm_destroy_session(session, err);
+		sessions[conn]  = nil;
 		session = nil;
 	end
 end
 
-
-function handle_request(method, body, request)
-	if request.method ~= "GET" or request.headers["upgrade"] ~= "WebSocket" or request.headers["connection"] ~= "Upgrade" then
-		if request.method == "OPTIONS" then
-			return { headers = default_headers, body = "" };
-		else
-			return "<html><body>You really don't look like a Websocket client to me... what do you want?</body></html>";
-		end
-	end
-
-	local subprotocol = request.headers["Websocket-Protocol"];
-	if subprotocol ~= nil and subprotocol ~= "XMPP" then
-		return "<html><body>You really don't look like an XMPP Websocket client to me... what do you want?</body></html>";
-	end
-
-	if not method then
-		log("debug", "Request %s suffered error %s", tostring(request.id), body);
-		return;
-	end
-
-	request.conn:setlistener(websocket_listener);
-	request.write("HTTP/1.1 101 Web Socket Protocol Handshake\r\n");
-	request.write("Upgrade: WebSocket\r\n");
-	request.write("Connection: Upgrade\r\n");
-	request.write("WebSocket-Origin: file://\r\n"); -- FIXME
-	request.write("WebSocket-Location: ws://localhost:5281/xmpp-websocket\r\n"); -- FIXME
-	request.write("WebSocket-Protocol: XMPP\r\n");
-	request.write("\r\n");
-
-	return true;
+function listener.associate_session(conn, session)
+	sessions[conn] = session;
 end
 
-local function setup()
-	local ports = module:get_option("websocket_ports") or { 5281 };
-	httpserver.new_from_config(ports, handle_request, { base = "xmpp-websocket" });
+function handle_request(event, path)
+	local request, response = event.request, event.response;
+
+	-- Add sanity checks
+
+	response.conn:setlistener(listener);
+	response.status = "101 Switching Protocols";
+	response.headers.Upgrade = "websocket";
+	response.headers.Connection = "Upgrade";
+	response.headers.Sec_WebSocket_Accept = base64(sha1(request.headers.sec_websocket_key .. "258EAFA5-E914-47DA-95CA-C5AB0DC85B11"));
+	response.headers.Sec_WebSocket_Protocol = "xmpp";
+
+	return "";
 end
-if prosody.start_time then -- already started
-	setup();
-else
-	prosody.events.add_handler("server-started", setup);
+
+function module.load()
+	module:provides("http", {
+		name = "xmpp-websocket";
+		route = {
+			["GET /*"] = handle_request;
+		};
+	});
 end