diff --git a/lib/server.js b/lib/server.js new file mode 100644 index 0000000..59656b0 --- /dev/null +++ b/lib/server.js @@ -0,0 +1,579 @@ +'use strict'; + +var url = require('url'); +var sni = require('sni'); +var Packer = require('proxy-packer'); +var PromiseA; +try { + PromiseA = require('bluebird'); +} catch(e) { + PromiseA = global.Promise; +} + +function timeoutPromise(duration) { + return new PromiseA(function (resolve) { + setTimeout(resolve, duration); + }); +} +var Devices = require('./device-tracker'); +var pipeWs = require('./pipe-ws.js'); +var PortServers = {}; +var Server = { + _initCommandHandlers: function (state, srv) { + var commandHandlers = { + add_token: function addToken(newAuth) { + return Server.addToken(state, srv, newAuth); + } + , delete_token: function (token) { + return state.Promise.resolve(function () { + var err; + + if (token !== '*') { + err = Server.removeToken(state, srv, token); + if (err) { return state.Promise.reject(err); } + } + + Object.keys(srv.grants).some(function (jwtoken) { + err = Server.removeToken(state, srv, jwtoken); + return err; + }); + if (err) { return state.Promise.reject(err); } + + return null; + }); + } + }; + commandHandlers.auth = commandHandlers.add_token; + commandHandlers.authn = commandHandlers.add_token; + commandHandlers.authz = commandHandlers.add_token; + srv._commandHandlers = commandHandlers; + } +, _initPackerHandlers: function (state, srv) { + var packerHandlers = { + oncontrol: function (tun) { + var cmd; + try { + cmd = JSON.parse(tun.data.toString()); + } catch (e) {} + if (!Array.isArray(cmd) || typeof cmd[0] !== 'number') { + var msg = 'received bad command "' + tun.data.toString() + '"'; + console.warn(msg, 'from websocket', srv.socketId); + Server.sendTunnelMsg(srv, null, [0, {message: msg, code: 'E_BAD_COMMAND'}], 'control'); + return; + } + + if (cmd[0] < 0) { + // We only ever send one command and we send it once, so we just hard coded the ID as 1. + if (cmd[0] === -1) { + if (cmd[1]) { + console.warn('received error response to hello from', srv.socketId, cmd[1]); + } + } + else { + console.warn('received response to unknown command', cmd, 'from', srv.socketId); + } + return; + } + + if (cmd[0] === 0) { + console.warn('received dis-associated error from', srv.socketId, cmd[1]); + return; + } + + function onSuccess() { + Server.sendTunnelMsg(srv, null, [-cmd[0], null], 'control'); + } + function onError(err) { + Server.sendTunnelMsg(srv, null, [-cmd[0], err], 'control'); + } + + if (!srv._commandHandlers[cmd[1]]) { + onError({ message: 'unknown command "'+cmd[1]+'"', code: 'E_UNKNOWN_COMMAND' }); + return; + } + + console.log('command:', cmd[1], cmd.slice(2)); + return srv._commandHandlers[cmd[1]].apply(null, cmd.slice(2)).then(onSuccess, onError); + } + + , onconnection: function (/*tun*/) { + // I don't think this event can happen since this relay + // is acting the part of the client, but just in case... + // (in fact it should probably be explicitly disallowed) + console.error("[SANITY FAIL] reverse connection start"); + } + + , onmessage: function (tun) { + var cid = Packer.addrToId(tun); + if (state.debug) { console.log("remote '" + Server.logName(state, srv) + "' has data for '" + cid + "'", tun.data.byteLength); } + + var browserConn = Server.getBrowserConn(state, srv, cid); + if (!browserConn) { + Server.sendTunnelMsg(srv, tun, {message: 'no matching connection', code: 'E_NO_CONN'}, 'error'); + return; + } + + browserConn.write(tun.data); + // tunnelRead is how many bytes we've read from the tunnel, and written to the browser. + browserConn.tunnelRead = (browserConn.tunnelRead || 0) + tun.data.byteLength; + // If we have more than 1MB buffered data we need to tell the other side to slow down. + // Once we've finished sending what we have we can tell the other side to keep going. + // If we've already sent the 'pause' message though don't send it again, because we're + // probably just dealing with data queued before our message got to them. + if (!browserConn.remotePaused && browserConn.bufferSize > 1024*1024) { + Server.sendTunnelMsg(srv, tun, browserConn.tunnelRead, 'pause'); + browserConn.remotePaused = true; + + browserConn.once('drain', function () { + Server.sendTunnelMsg(srv, tun, browserConn.tunnelRead, 'resume'); + browserConn.remotePaused = false; + }); + } + } + + , onpause: function (tun) { + var cid = Packer.addrToId(tun); + console.log('[TunnelPause]', cid); + var browserConn = Server.getBrowserConn(state, srv, cid); + if (browserConn) { + browserConn.manualPause = true; + browserConn.pause(); + } else { + Server.sendTunnelMsg(srv, tun, {message: 'no matching connection', code: 'E_NO_CONN'}, 'error'); + } + } + + , onresume: function (tun) { + var cid = Packer.addrToId(tun); + console.log('[TunnelResume]', cid); + var browserConn = Server.getBrowserConn(state, srv, cid); + if (browserConn) { + browserConn.manualPause = false; + browserConn.resume(); + } else { + Server.sendTunnelMsg(srv, tun, {message: 'no matching connection', code: 'E_NO_CONN'}, 'error'); + } + } + + , onend: function (tun) { + var cid = Packer.addrToId(tun); + console.log('[TunnelEnd]', cid); + Server.closeBrowserConn(state, srv, cid); + } + , onerror: function (tun) { + var cid = Packer.addrToId(tun); + console.warn('[TunnelError]', cid, tun.message); + Server.closeBrowserConn(state, srv, cid); + } + }; + srv._packerHandlers = packerHandlers; + srv.unpacker = Packer.create(srv._packerHandlers); + } +, _initSocketHandlers: function (state, srv) { + function refreshTimeout() { + srv.lastActivity = Date.now(); + } + + function checkTimeout() { + // Determine how long the connection has been "silent", ie no activity. + var silent = Date.now() - srv.lastActivity; + + // If we have had activity within the last activityTimeout then all we need to do is + // call this function again at the soonest time when the connection could be timed out. + if (silent < state.activityTimeout) { + srv.timeoutId = setTimeout(checkTimeout, state.activityTimeout - silent); + } + + // Otherwise we check to see if the pong has also timed out, and if not we send a ping + // and call this function again when the pong will have timed out. + else if (silent < state.activityTimeout + state.pongTimeout) { + if (state.debug) { console.log('pinging', Server.logName(state, srv)); } + try { + srv.ws.ping(); + } catch (err) { + console.warn('failed to ping home cloud', Server.logName(state, srv)); + } + srv.timeoutId = setTimeout(checkTimeout, state.pongTimeout); + } + + // Last case means the ping we sent before didn't get a response soon enough, so we + // need to close the websocket connection. + else { + console.warn('home cloud', Server.logName(state, srv), 'connection timed out'); + srv.ws.close(1013, 'connection timeout'); + } + } + + function forwardMessage(chunk) { + refreshTimeout(); + if (state.debug) { console.log('[ws] device => client : demultiplexing message ', chunk.byteLength, 'bytes'); } + //console.log(chunk.toString()); + srv.unpacker.fns.addChunk(chunk); + } + + function hangup() { + clearTimeout(srv.timeoutId); + console.log('[ws] device hangup', Server.logName(state, srv), 'connection closing'); + // remove the allowed domains from the list (but leave the socket) + Object.keys(srv.grants).forEach(function (jwtoken) { + Server.removeToken(state, srv, jwtoken); + }); + srv.ws.terminate(); + // remove the socket from the list, period + Devices.close(state.deviceLists, srv); + } + + srv.lastActivity = Date.now(); + srv.timeoutId = null; + srv.timeoutId = setTimeout(checkTimeout, state.activityTimeout); + + // Note that our websocket library automatically handles pong responses on ping requests + // before it even emits the event. + srv.ws.on('ping', refreshTimeout); + srv.ws.on('pong', refreshTimeout); + srv.ws.on('message', forwardMessage); + srv.ws.on('close', hangup); + srv.ws.on('error', hangup); + } +, init: function init(state, srv) { + Server._initCommandHandlers(state, srv); + Server._initPackerHandlers(state, srv); + Server._initSocketHandlers(state, srv); + + // Status Code '1' for Status 'hello' + Server.sendTunnelMsg(srv, null, [1, 'hello', [srv.unpacker._version], Object.keys(srv._commandHandlers)], 'control'); + } +, sendTunnelMsg: function sendTunnelMsg(srv, addr, data, service) { + if (data && !Buffer.isBuffer()) { + data = Buffer.from(JSON.stringify(data)); + } + srv.ws.send(Packer.packHeader(addr, data, service), {binary: true}); + srv.ws.send(data, {binary: true}); + } +, logName: function logName(state, srv) { + var result = Object.keys(srv.grants).map(function (jwtoken) { + return srv.grants[jwtoken].currentDesc; + }).join(';'); + + return result || srv.socketId; + } +, onAuth: function onAuth(state, srv, rawAuth, grant) { + console.log('\n[relay.js] onAuth'); + console.log(rawAuth); + //console.log(grant); + //var stringauth; + var err; + if (!grant || 'object' !== typeof grant) { + console.log('[relay.js] invalid token', grant); + err = new Error("invalid access token"); + err.code = "E_INVALID_TOKEN"; + return state.Promise.reject(err); + } + + // deprecated (for json object on connect) + if ('string' !== typeof rawAuth) { + rawAuth = JSON.stringify(rawAuth); + } + + // TODO don't fire the onAuth event on non-authz updates + if (!grant.jwt && !(grant.domains||[]).length && !(grant.ports||[]).length) { + console.log("[onAuth] nothing to offer at all"); + return null; + } + + console.log('[onAuth] check for upgrade token'); + //console.log(grant); + if (grant.jwt) { + if (rawAuth !== grant.jwt) { + console.log('[onAuth] token is new'); + } + // TODO only send token when new + if (true) { + // Access Token + console.log('[onAuth] sending back token'); + Server.sendTunnelMsg( + srv + , null + , [ 3 + , 'access_token' + , { jwt: grant.jwt } + ] + , 'control' + ); + // these aren't needed internally once they're sent + grant.jwt = null; + } + } + + /* + if (!Array.isArray(grant.domains) || !grant.domains.length) { + err = new Error("invalid domains array"); + err.code = "E_INVALID_NAME"; + return state.Promise.reject(err); + } + */ + if (grant.domains.some(function (name) { return typeof name !== 'string'; })) { + console.log('bad domain names'); + err = new Error("invalid domain name(s)"); + err.code = "E_INVALID_NAME"; + return state.Promise.reject(err); + } + + console.log('[onAuth] strolling through pleasantries'); + // Add the custom properties we need to manage this remote, then add it to all the relevant + // domains and the list of all this websocket's grants. + grant.domains.forEach(function (domainname) { + console.log('add', domainname, 'to device lists'); + srv.domainsMap[domainname] = true; + Devices.add(state.deviceLists, domainname, srv); + // TODO allow subs to go to individual devices + Devices.alias(state.deviceLists, domainname, '*.' + domainname); + }); + srv.domains = Object.keys(srv.domainsMap); + srv.currentDesc = (grant.device && (grant.device.id || grant.device.hostname)) || srv.domains.join(','); + grant.currentDesc = (grant.device && (grant.device.id || grant.device.hostname)) || grant.domains.join(','); + //grant.srv = srv; + //grant.ws = srv.ws; + //grant.upgradeReq = srv.upgradeReq; + grant.clients = {}; + + if (!grant.ports) { grant.ports = []; } + + function openPort(serviceport) { + function tcpListener(conn) { + Server.onDynTcpConn(state, srv, srv.portsMap[serviceport], conn); + } + serviceport = parseInt(serviceport, 10) || 0; + if (!serviceport) { + // TODO error message about bad port + return; + } + if (PortServers[serviceport]) { + console.log('reuse', serviceport, 'for this connection'); + //grant.ports = []; + srv.portsMap[serviceport] = PortServers[serviceport]; + srv.portsMap[serviceport].on('connection', tcpListener); + srv.portsMap[serviceport].tcpListener = tcpListener; + Devices.addPort(state.deviceLists, serviceport, srv); + } else { + try { + console.log('use new', serviceport, 'for this connection'); + srv.portsMap[serviceport] = PortServers[serviceport] = require('net').createServer(tcpListener); + srv.portsMap[serviceport].tcpListener = tcpListener; + srv.portsMap[serviceport].listen(serviceport, function () { + console.info('[DynTcpConn] Port', serviceport, 'now open for', grant.currentDesc); + Devices.addPort(state.deviceLists, serviceport, srv); + }); + srv.portsMap[serviceport].on('error', function (e) { + // TODO try again with random port + console.error("Server Error assigning a dynamic port to a new connection:", e); + }); + } catch(e) { + // what a wonderful problem it will be the day that this bug needs to be fixed + // (i.e. there are enough users to run out of ports) + console.error("Error assigning a dynamic port to a new connection:", e); + } + } + } + grant.ports.forEach(openPort); + + console.info("[ws] authorized", srv.socketId, "for", grant.currentDesc); + console.log('notify of grants', grant.domains, grant.ports); + srv.grants[rawAuth] = grant; + Server.sendTunnelMsg( + srv + , null + , [ 2 + , 'grant' + , [ ['ssh+https', grant.domains[0], 443 ] + // TODO the shared domain should be token specific + , ['ssh', 'ssh.' + state.config.sharedDomain, [grant.ports[0]] ] + , ['tcp', 'tcp.' + state.config.sharedDomain, [grant.ports[0]] ] + , ['https', grant.domains[0] ] + ] + ] + , 'control' + ); + return null; + } +, onDynTcpConn: function onDynTcpConn(state, srv, server, conn) { + var serviceport = server.address().port; + console.log('[DynTcpConn] new connection on', serviceport); + var nextDevice = Devices.next(state.deviceLists, serviceport); + + if (!nextDevice) { + conn.write("[Sanity Error] I've got a blank space baby, but nowhere to write your name."); + conn.end(); + try { + server.close(); + } catch(e) { + console.error("[DynTcpConn] failed to close server:", e); + } + return; + } + + // When using raw TCP we're already paired to the client by port + // and we can begin connecting right away, but we'll wait just a sec + // to reject known bad connections + var sendConnection = setTimeout(function () { + conn.removeListener('data', peekFirstPacket); + console.log("[debug tcp conn] Connecting possible telnet client to device..."); + pipeWs(null, 'tcp', nextDevice, conn, serviceport); + }, 350); + function peekFirstPacket(firstChunk) { + clearTimeout(sendConnection); + if (state.debug) { console.log("[DynTcp]", serviceport, "examining firstChunk from", Packer.socketToId(conn)); } + conn.pause(); + //conn.unshift(firstChunk); + conn._handle.onread(firstChunk.length, firstChunk); + + var servername; + var hostname; + var str; + var m; + + if (22 === firstChunk[0]) { + servername = (sni(firstChunk)||'').toLowerCase(); + } else if (firstChunk[0] > 32 && firstChunk[0] < 127) { + str = firstChunk.toString(); + m = str.match(/(?:^|[\r\n])Host: ([^\r\n]+)[\r\n]*/im); + hostname = (m && m[1].toLowerCase() || '').split(':')[0]; + } + + if (servername || hostname) { + if (servername) { + conn.write("TLS with sni is allowed only on standard ports. If you've registered '" + servername + "' use port 443."); + } else { + conn.write("HTTP with Host headers is not allowed on dynamic ports. If you've registered '" + hostname + "' use port 80."); + } + conn.end(); + return; + } + + // pipeWs(servername, servicename, srv, client, serviceport) + // remote.clients is managed as part of the piping process + if (state.debug) { console.log("[DynTcp]", serviceport, "piping to srv (via loadbal)"); } + pipeWs(null, 'tcp', nextDevice, conn, serviceport); + + process.nextTick(function () { conn.resume(); }); + } + conn.once('data', peekFirstPacket); + } +, addToken: function addToken(state, srv, rawAuth) { + console.log("[addToken]", rawAuth); + if (srv.grants[rawAuth]) { + console.log("addToken - duplicate"); + // return { message: "token sent multiple times", code: "E_TOKEN_REPEAT" }; + return state.Promise.resolve(null); + } + + // [Extension] [Auth] This is where authentication is either handed off to + // an extension or the default authencitation handler. + return state.authenticate({ auth: rawAuth }).then(function (validatedTokenData) { + console.log('\n[relay.js] rawAuth'); + console.log(rawAuth); + + console.log('\n[relay.js] authnToken'); + console.log(validatedTokenData); + + // For tracking state between token exchanges + // and tacking on extra attributes (i.e. for extensions) + // TODO close on delete + if (!state.srvs[validatedTokenData.id]) { + state.srvs[validatedTokenData.id] = {}; + } + if (!state.srvs[validatedTokenData.id].updateAuth) { + // be sure to always pass latest srv since the connection may change + // and reuse the same token + state.srvs[validatedTokenData.id].updateAuth = function (srv, validatedTokenData) { + return Server.onAuth(state, srv, rawAuth, validatedTokenData); + }; + } + state.srvs[validatedTokenData.id].updateAuth(srv, validatedTokenData); + }); + } +, removeToken: function removeToken(state, srv, jwtoken) { + var grant = srv.grants[jwtoken]; + if (!grant) { + return { message: 'specified token not present', code: 'E_INVALID_TOKEN'}; + } + + // Prevent any more browser connections for this grant being sent to this srv, + // and any existing connections from trying to send more data across the connection. + grant.domains.forEach(function (domainname) { + Devices.remove(state.deviceLists, domainname, srv); + }); + grant.ports.forEach(function (portnumber) { + Devices.remove(state.deviceLists, portnumber, srv); + if (!srv.portsMap[portnumber]) { return; } + try { + srv.portsMap[portnumber].close(function () { + console.log("[DynTcpConn] closing server for ", portnumber); + delete srv.portsMap[portnumber]; + delete PortServers[portnumber]; + }); + } catch(e) { /*ignore*/ } + }); + + // Close all of the existing browser connections associated with this websocket connection. + Object.keys(grant.clients).forEach(function (cid) { + Server.closeBrowserConn(state, srv, cid); + }); + delete srv.grants[jwtoken]; + console.log("[ws] removed token '" + grant.currentDesc + "' from", srv.socketId); + return null; + } +, getBrowserConn: function getBrowserConn(state, srv, cid) { + return srv.clients[cid]; + } +, closeBrowserConn: function closeBrowserConn(state, srv, cid) { + if (!srv.clients[cid]) { + return; + } + + PromiseA.resolve().then(function () { + var conn = srv.clients[cid]; + conn.tunnelClosing = true; + conn.end(); + + // If no data is buffered for writing then we don't need to wait for it to drain. + if (!conn.bufferSize) { + return timeoutPromise(500); + } + // Otherwise we want the connection to be able to finish, but we also want to impose + // a time limit for it to drain, since it shouldn't have more than 1MB buffered. + return new PromiseA(function (resolve) { + var timeoutId = setTimeout(resolve, 60*1000); + conn.once('drain', function () { + clearTimeout(timeoutId); + setTimeout(resolve, 500); + }); + }); + }).then(function () { + if (srv.clients[cid]) { + console.warn(cid, 'browser connection still present after calling `end`'); + srv.clients[cid].destroy(); + return timeoutPromise(500); + } + }).then(function () { + if (srv.clients[cid]) { + console.error(cid, 'browser connection still present after calling `destroy`'); + delete srv.clients[cid]; + } + }).catch(function (err) { + console.warn('failed to close browser connection', cid, err); + }); + } +, parseAuth: function parseAuth(state, srv) { + var authn = (srv.upgradeReq.headers.authorization||'').split(/\s+/); + if (authn[0] && 'basic' === authn[0].toLowerCase()) { + try { + authn = new Buffer(authn[1], 'base64').toString('ascii').split(':'); + return authn[1]; + } catch (err) { } + } + return url.parse(srv.upgradeReq.url, true).query.access_token; + } +}; + +module.exports = Server;