/* jshint esversion: 6, asi: true, node: true */ /* eslint no-unused-expressions: ["error", { "allowShortCircuit": true, "allowTernary": true }], no-console: ["error", { allow: ["warn", "error"] }] */ // app.js // eslint-disable-next-line import/order const config = require('./config'); const path = require('path'); const nodeRoot = path.dirname(require.main.filename); const publicPath = path.join(nodeRoot, 'client', 'public'); const express = require('express'); const logger = require('morgan'); const app = express(); const server = require('http').Server(app); const validator = require('validator'); const favicon = require('serve-favicon'); const io = require('socket.io')(server, { serveClient: false, path: '/ssh/socket.io', origins: config.http.origins, }); const session = require('express-session')({ secret: config.session.secret, name: config.session.name, resave: true, saveUninitialized: false, unset: 'destroy', }); const appSocket = require('./socket'); const expressOptions = require('./expressOptions'); const myutil = require('./util'); myutil.setDefaultCredentials( config.user.name, config.user.password, config.user.privatekey, config.user.overridebasic ); // safe shutdown let shutdownMode = false; let shutdownInterval = 0; let connectionCount = 0; // eslint-disable-next-line consistent-return function safeShutdownGuard(req, res, next) { if (shutdownMode) { res.status(503).end('Service unavailable: Server shutting down'); } else { return next(); } } // clean stop function stopApp(reason) { shutdownMode = false; // eslint-disable-next-line no-console if (reason) console.log(`Stopping: ${reason}`); if (shutdownInterval) clearInterval(shutdownInterval); io.close(); server.close(); } module.exports = { server, config }; // express app.use(safeShutdownGuard); app.use(session); app.use(myutil.basicAuth); if (config.accesslog) app.use(logger('common')); app.disable('x-powered-by'); // static files app.use('/ssh', express.static(publicPath, expressOptions)); // favicon from root if being pre-fetched by browser to prevent a 404 app.use(favicon(path.join(publicPath, 'favicon.ico'))); app.get('/ssh/reauth', (req, res) => { const r = req.headers.referer || '/'; res .status(401) .send( `` ); }); // eslint-disable-next-line complexity app.get('/ssh/host/:host?', (req, res) => { res.sendFile(path.join(path.join(publicPath, 'client.htm'))); // capture, assign, and validate variables req.session.ssh = { host: config.ssh.host || (validator.isIP(`${req.params.host}`) && req.params.host) || (validator.isFQDN(req.params.host) && req.params.host) || (/^(([a-z]|[A-Z]|[0-9]|[!^(){}\-_~])+)?\w$/.test(req.params.host) && req.params.host), port: (validator.isInt(`${req.query.port}`, { min: 1, max: 65535 }) && req.query.port) || config.ssh.port, localAddress: config.ssh.localAddress, localPort: config.ssh.localPort, header: { name: req.query.header || config.header.text, background: req.query.headerBackground || config.header.background, }, algorithms: config.algorithms, keepaliveInterval: config.ssh.keepaliveInterval, keepaliveCountMax: config.ssh.keepaliveCountMax, allowedSubnets: config.ssh.allowedSubnets, term: (/^(([a-z]|[A-Z]|[0-9]|[!^(){}\-_~])+)?\w$/.test(req.query.sshterm) && req.query.sshterm) || config.ssh.term, terminal: { cursorBlink: validator.isBoolean(`${req.query.cursorBlink}`) ? myutil.parseBool(req.query.cursorBlink) : config.terminal.cursorBlink, scrollback: validator.isInt(`${req.query.scrollback}`, { min: 1, max: 200000 }) && req.query.scrollback ? req.query.scrollback : config.terminal.scrollback, tabStopWidth: validator.isInt(`${req.query.tabStopWidth}`, { min: 1, max: 100 }) && req.query.tabStopWidth ? req.query.tabStopWidth : config.terminal.tabStopWidth, bellStyle: req.query.bellStyle && ['sound', 'none'].indexOf(req.query.bellStyle) > -1 ? req.query.bellStyle : config.terminal.bellStyle, }, allowreplay: config.options.challengeButton || (validator.isBoolean(`${req.headers.allowreplay}`) ? myutil.parseBool(req.headers.allowreplay) : false), allowreauth: config.options.allowreauth || false, mrhsession: validator.isAlphanumeric(`${req.headers.mrhsession}`) && req.headers.mrhsession ? req.headers.mrhsession : 'none', serverlog: { client: config.serverlog.client || false, server: config.serverlog.server || false, }, readyTimeout: (validator.isInt(`${req.query.readyTimeout}`, { min: 1, max: 300000 }) && req.query.readyTimeout) || config.ssh.readyTimeout, }; if (req.session.ssh.header.name) validator.escape(req.session.ssh.header.name); if (req.session.ssh.header.background) validator.escape(req.session.ssh.header.background); }); // express error handling app.use((req, res) => { res.status(404).send("Sorry, can't find that!"); }); app.use((err, req, res) => { console.error(err.stack); res.status(500).send('Something broke!'); }); // bring up socket io.on('connection', appSocket); // socket.io // expose express session with socket.request.session io.use((socket, next) => { socket.request.res ? session(socket.request, socket.request.res, next) : next(next); // eslint disable-line }); io.on('connection', (socket) => { connectionCount += 1; socket.on('disconnect', () => { connectionCount -= 1; if (connectionCount <= 0 && shutdownMode) { stopApp('All clients disconnected'); } }); }); const signals = ['SIGTERM', 'SIGINT']; signals.forEach((signal) => process.on(signal, () => { if (shutdownMode) stopApp('Safe shutdown aborted, force quitting'); else if (connectionCount > 0) { let remainingSeconds = config.safeShutdownDuration; shutdownMode = true; const message = connectionCount === 1 ? ' client is still connected' : ' clients are still connected'; console.error(connectionCount + message); console.error(`Starting a ${remainingSeconds} seconds countdown`); console.error('Press Ctrl+C again to force quit'); shutdownInterval = setInterval(() => { remainingSeconds -= 1; if (remainingSeconds <= 0) { stopApp('Countdown is over'); } else { io.sockets.emit('shutdownCountdownUpdate', remainingSeconds); } }, 1000); } else stopApp(); }) );