tunnel-ssh/index.js

var net = require('net');
var debug = require('debug')('tunnel-ssh');
var Connection = require('ssh2');
var createConfig = require('./lib/config');

function bindSSHConnection(config, netConnection) {
  var sshConnection = new Connection();

  sshConnection.on('ready', function() {
    debug('sshConnection:ready');
    netConnection.emit('sshConnection', sshConnection, netConnection);

    sshConnection.forwardOut(
    config.srcHost,
    config.srcPort,
    config.dstHost,
    config.dstPort, function(err, sshStream) {
      if (err) {
        if (!config.keepAlive) {
          server.close();
        }
        // Bubble up the error => netConnection => server
        netConnection.emit('error', err);
        debug('Destination port:', err);
        return;
      }
      sshStream.once('close', function() {
        debug('sshStream:close');
        if (config.keepAlive) {
          sshConnection.end();
        }
      });
      debug('sshStream:create');
      netConnection.pipe(sshStream).pipe(netConnection);
      netConnection.emit('sshStream', sshStream);
    });
  });
  return sshConnection;
}

function createServer(config) {
  var server,
  sshConnection,
  connections = [];

  server = net.createServer(function(netConnection) {
    netConnection.on('error', server.emit.bind(server, 'error'));
    server.emit('netConnection', netConnection, server);
    sshConnection = bindSSHConnection(config, netConnection);
    netConnection.on('sshStream', function(sshStream) {
      sshStream.once('close', function() {
        debug('sshStream:close');
        if (!config.keepAlive) {
          server.close();
        }
      });
    });
    connections.push(sshConnection, netConnection);
    sshConnection.connect(config);
  });

  server.on('close', function() {
    connections.forEach(function(connection) {
      connection.end();
    });
  });

  return server;
}

function tunnel(configArgs, callback) {

  try {
    var config = createConfig(configArgs);
  } catch (e) {
    callback(null, e);
  }

  return createServer(config).listen(config.localPort, config.localHost, callback);
}
tunnel.reverse = require('./lib/reverse');
module.exports = tunnel;