/** * @description MeshCentral MSTSC & SSH relay * @author Ylian Saint-Hilaire & Bryan Roe * @copyright Intel Corporation 2018-2021 * @license Apache-2.0 * @version v0.0.1 */ /*jslint node: true */ /*jshint node: true */ /*jshint strict:false */ /*jshint -W097 */ /*jshint esversion: 6 */ "use strict"; // Construct a MSTSC Relay object, called upon connection // This is a bit of a hack as we are going to run the RDP connection thru a loopback connection. // If the "node-rdpjs-2" module supported passing a socket, we would do something different. module.exports.CreateMstscRelay = function (parent, db, ws, req, args, domain) { const Net = require('net'); const WebSocket = require('ws'); var obj = {}; obj.ws = ws; obj.tcpServerPort = 0; obj.relayActive = false; var rdpClient = null; parent.parent.debug('relay', 'RDP: Request for RDP relay (' + req.clientIp + ')'); // Disconnect obj.close = function (arg) { if (obj.ws == null) return; // Collect how many raw bytes where received and sent. // We sum both the websocket and TCP client in this case. //var inTraffc = obj.ws._socket.bytesRead, outTraffc = obj.ws._socket.bytesWritten; //if (obj.wsClient != null) { inTraffc += obj.wsClient._socket.bytesRead; outTraffc += obj.wsClient._socket.bytesWritten; } //console.log('WinRDP - in', inTraffc, 'out', outTraffc); if (obj.wsClient) { obj.wsClient.close(); delete obj.wsClient; } if (obj.tcpServer) { obj.tcpServer.close(); obj.tcpServer.destroy(); delete obj.tcpServer; } if (rdpClient) { rdpClient.close(); rdpClient = null; } if ((arg == 1) || (arg == null)) { try { ws.close(); } catch (e) { console.log(e); } } // Soft close, close the websocket if (arg == 2) { try { ws._socket._parent.end(); } catch (e) { console.log(e); } } // Hard close, close the TCP socket obj.ws.removeAllListeners(); obj.relayActive = false; delete obj.ws; }; // Start the looppback server function startTcpServer() { obj.tcpServer = new Net.Server(); obj.tcpServer.listen(0, '127.0.0.1', function () { obj.tcpServerPort = obj.tcpServer.address().port; startRdp(obj.tcpServerPort); }); obj.tcpServer.on('connection', function (socket) { if (obj.relaySocket != null) { socket.close(); } else { obj.relaySocket = socket; obj.relaySocket.pause(); obj.relaySocket.on('data', function (chunk) { // Make sure to handle flow control. if (obj.relayActive == true) { obj.relaySocket.pause(); obj.wsClient.send(chunk, function () { obj.relaySocket.resume(); }); } }); obj.relaySocket.on('end', function () { obj.close(); }); obj.relaySocket.on('error', function (err) { obj.close(); }); // Decode the authentication cookie var cookie = parent.parent.decodeCookie(obj.infos.ip, parent.parent.loginCookieEncryptionKey); if (cookie == null) return; // Setup the correct URL with domain and use TLS only if needed. var options = { rejectUnauthorized: false }; if (domain.dns != null) { options.servername = domain.dns; } var protocol = (args.tlsoffload) ? 'ws' : 'wss'; var domainadd = ''; if ((domain.dns == null) && (domain.id != '')) { domainadd = domain.id + '/' } var url = protocol + '://127.0.0.1:' + args.port + '/' + domainadd + ((cookie.lc == 1) ? 'local' : 'mesh') + 'relay.ashx?noping=1&p=10&auth=' + obj.infos.ip; // Protocol 10 is Web-RDP parent.parent.debug('relay', 'RDP: Connection websocket to ' + url); obj.wsClient = new WebSocket(url, options); obj.wsClient.on('open', function () { parent.parent.debug('relay', 'RDP: Relay websocket open'); }); obj.wsClient.on('message', function (data) { // Make sure to handle flow control. if ((obj.relayActive == false) && (data == 'c')) { obj.relayActive = true; obj.relaySocket.resume(); } else { obj.wsClient._socket.pause(); obj.relaySocket.write(data, function () { obj.wsClient._socket.resume(); }); } }); obj.wsClient.on('close', function () { parent.parent.debug('relay', 'RDP: Relay websocket closed'); obj.close(); }); obj.wsClient.on('error', function (err) { parent.parent.debug('relay', 'RDP: Relay websocket error: ' + err); obj.close(); }); obj.tcpServer.close(); obj.tcpServer = null; } }); } // Start the RDP client function startRdp(port) { parent.parent.debug('relay', 'RDP: Starting RDP client on loopback port ' + port); try { rdpClient = require('node-rdpjs-2').createClient({ logLevel: 'ERROR', domain: obj.infos.domain, userName: obj.infos.username, password: obj.infos.password, enablePerf: true, autoLogin: true, screen: obj.infos.screen, locale: obj.infos.locale }).on('connect', function () { send(['rdp-connect']); }).on('bitmap', function (bitmap) { try { ws.send(bitmap.data); } catch (ex) { } // Send the bitmap data as binary delete bitmap.data; send(['rdp-bitmap', bitmap]); // Send the bitmap metadata seperately, without bitmap data. }).on('close', function () { send(['rdp-close']); }).on('error', function (err) { send(['rdp-error', err]); }).connect('127.0.0.1', obj.tcpServerPort); } catch (ex) { console.log('startRdpException', ex); obj.close(); } } // When data is received from the web socket // RDP default port is 3389 ws.on('message', function (msg) { try { msg = JSON.parse(msg); switch (msg[0]) { case 'infos': { obj.infos = msg[1]; startTcpServer(); break; } case 'mouse': { if (rdpClient) { rdpClient.sendPointerEvent(msg[1], msg[2], msg[3], msg[4]); } break; } case 'wheel': { if (rdpClient) { rdpClient.sendWheelEvent(msg[1], msg[2], msg[3], msg[4]); } break; } case 'scancode': { if (rdpClient) { rdpClient.sendKeyEventScancode(msg[1], msg[2]); } break; } case 'unicode': { if (rdpClient) { rdpClient.sendKeyEventUnicode(msg[1], msg[2]); } break; } case 'disconnect': { obj.close(); break; } } } catch (ex) { console.log('RdpMessageException', msg, ex); obj.close(); } }); // If error, do nothing ws.on('error', function (err) { parent.parent.debug('relay', 'RDP: Browser websocket error: ' + err); obj.close(); }); // If the web socket is closed ws.on('close', function (req) { parent.parent.debug('relay', 'RDP: Browser websocket closed'); obj.close(); }); // Send an object with flow control function send(obj) { try { rdpClient.bufferLayer.socket.pause(); } catch (ex) { } try { ws.send(JSON.stringify(obj), function () { try { rdpClient.bufferLayer.socket.resume(); } catch (ex) { } }); } catch (ex) { } } // We are all set, start receiving data ws._socket.resume(); return obj; }; // Construct a SSH Relay object, called upon connection module.exports.CreateSshRelay = function (parent, db, ws, req, args, domain) { const Net = require('net'); const WebSocket = require('ws'); // SerialTunnel object is used to embed SSH within another connection. function SerialTunnel(options) { var obj = new require('stream').Duplex(options); obj.forwardwrite = null; obj.updateBuffer = function (chunk) { this.push(chunk); }; obj._write = function (chunk, encoding, callback) { if (obj.forwardwrite != null) { obj.forwardwrite(chunk); } if (callback) callback(); }; // Pass data written to forward obj._read = function (size) { }; // Push nothing, anything to read should be pushed from updateBuffer() obj.destroy = function () { delete obj.forwardwrite; } return obj; } const obj = {}; obj.ws = ws; obj.relayActive = false; parent.parent.debug('relay', 'SSH: Request for SSH relay (' + req.clientIp + ')'); // Disconnect obj.close = function (arg) { if (obj.ws == null) return; // Collect how many raw bytes where received and sent. // We sum both the websocket and TCP client in this case. //var inTraffc = obj.ws._socket.bytesRead, outTraffc = obj.ws._socket.bytesWritten; //if (obj.wsClient != null) { inTraffc += obj.wsClient._socket.bytesRead; outTraffc += obj.wsClient._socket.bytesWritten; } //console.log('WinSSH - in', inTraffc, 'out', outTraffc); if (obj.sshShell) { obj.sshShell.destroy(); obj.sshShell.removeAllListeners('data'); obj.sshShell.removeAllListeners('close'); try { obj.sshShell.end(); } catch (ex) { console.log(ex); } delete obj.sshShell; } if (obj.sshClient) { obj.sshClient.destroy(); obj.sshClient.removeAllListeners('ready'); try { obj.sshClient.end(); } catch (ex) { console.log(ex); } delete obj.sshClient; } if (obj.wsClient) { obj.wsClient.removeAllListeners('open'); obj.wsClient.removeAllListeners('message'); obj.wsClient.removeAllListeners('close'); try { obj.wsClient.close(); } catch (ex) { console.log(ex); } delete obj.wsClient; } if ((arg == 1) || (arg == null)) { try { ws.close(); } catch (e) { console.log(e); } } // Soft close, close the websocket if (arg == 2) { try { ws._socket._parent.end(); } catch (e) { console.log(e); } } // Hard close, close the TCP socket obj.ws.removeAllListeners(); obj.relayActive = false; delete obj.termSize; delete obj.cookie; delete obj.ws; }; // Decode the authentication cookie obj.cookie = parent.parent.decodeCookie(req.query.auth, parent.parent.loginCookieEncryptionKey); if (obj.cookie == null) { obj.ws.send(JSON.stringify({ action: 'sessionerror' })); obj.close(); return; } // Start the looppback server function startRelayConnection() { try { // Setup the correct URL with domain and use TLS only if needed. var options = { rejectUnauthorized: false }; if (domain.dns != null) { options.servername = domain.dns; } var protocol = 'wss'; if (args.tlsoffload) { protocol = 'ws'; } var domainadd = ''; if ((domain.dns == null) && (domain.id != '')) { domainadd = domain.id + '/' } var url = protocol + '://127.0.0.1:' + args.port + '/' + domainadd + ((obj.cookie.lc == 1) ? 'local' : 'mesh') + 'relay.ashx?noping=1&p=11&auth=' + req.query.auth; // Protocol 11 is Web-SSH parent.parent.debug('relay', 'SSH: Connection websocket to ' + url); obj.wsClient = new WebSocket(url, options); obj.wsClient.on('open', function () { parent.parent.debug('relay', 'SSH: Relay websocket open'); }); obj.wsClient.on('message', function (data) { // Make sure to handle flow control. if ((obj.relayActive == false) && (data == 'c')) { obj.relayActive = true; // Create a serial tunnel && SSH module obj.ser = new SerialTunnel(); const Client = require('ssh2').Client; obj.sshClient = new Client(); obj.sshClient.on('ready', function () { // Authentication was successful. obj.sshClient.shell(function (err, stream) { // Start a remote shell if (err) { obj.close(); return; } obj.sshShell = stream; obj.sshShell.setWindow(obj.termSize.rows, obj.termSize.cols, obj.termSize.height, obj.termSize.width); obj.sshShell.on('close', function () { obj.close(); }); obj.sshShell.on('data', function (data) { obj.ws.send('~' + data); }); }); obj.ws.send(JSON.stringify({ action: 'connected' })); }); obj.sshClient.on('error', function (err) { if (err.level == 'client-authentication') { obj.ws.send(JSON.stringify({ action: 'autherror' })); } obj.close(); }); // Setup the serial tunnel, SSH ---> Relay WS obj.ser.forwardwrite = function (data) { if ((data.length > 0) && (obj.wsClient != null)) { try { obj.wsClient.send(data); } catch (ex) { } } }; // Connect the SSH module to the serial tunnel var connectionOptions = { sock: obj.ser } if (typeof obj.username == 'string') { connectionOptions.username = obj.username; delete obj.username; } if (typeof obj.password == 'string') { connectionOptions.password = obj.password; delete obj.password; } obj.sshClient.connect(connectionOptions); // We are all set, start receiving data ws._socket.resume(); } else { // Relay WS --> SSH if ((data.length > 0) && (obj.ser != null)) { try { obj.ser.updateBuffer(data); } catch (ex) { console.log(ex); } } } }); obj.wsClient.on('close', function () { parent.parent.debug('relay', 'SSH: Relay websocket closed'); obj.close(); }); obj.wsClient.on('error', function (err) { parent.parent.debug('relay', 'SSH: Relay websocket error: ' + err); obj.close(); }); } catch (ex) { console.log(ex); } } // When data is received from the web socket // SSH default port is 22 ws.on('message', function (msg) { try { if (typeof msg != 'string') return; if (msg[0] == '{') { // Control data msg = JSON.parse(msg); if (typeof msg.action != 'string') return; switch (msg.action) { case 'connect': { obj.termSize = msg; obj.username = msg.username; obj.password = msg.password; startRelayConnection(); break; } case 'resize': { obj.termSize = msg; if (obj.sshShell != null) { obj.sshShell.setWindow(obj.termSize.rows, obj.termSize.cols, obj.termSize.height, obj.termSize.width); } break; } } } else if (msg[0] == '~') { // Terminal data if (obj.sshShell != null) { obj.sshShell.write(msg.substring(1)); } } } catch (ex) { obj.close(); } }); // If error, do nothing ws.on('error', function (err) { parent.parent.debug('relay', 'SSH: Browser websocket error: ' + err); obj.close(); }); // If the web socket is closed ws.on('close', function (req) { parent.parent.debug('relay', 'SSH: Browser websocket closed'); obj.close(); }); return obj; };