Function openChannel

lib/server.js:1335–1373

(self, type, opts, cb)

function openChannel(self, type, opts, cb) {
  // Ask the client to open a channel for some purpose (e.g. a forwarded TCP
  // connection)
  const initWindow = MAX_WINDOW;
  const maxPacket = PACKET_SIZE;

  if (typeof opts === 'function') {
    cb = opts;
    opts = {};
  }

  const wrapper = (err, stream) => {
    cb(err, stream);
  };
  wrapper.type = type;

  const localChan = self._chanMgr.add(wrapper);

  if (localChan === -1) {
    cb(new Error('No free channels available'));
    return;
  }

  switch (type) {
    case 'forwarded-tcpip':
      self._protocol.forwardedTcpip(localChan, initWindow, maxPacket, opts);
      break;
    case 'x11':
      self._protocol.x11(localChan, initWindow, maxPacket, opts);
      break;
    case 'forwarded-streamlocal@openssh.com':
      self._protocol.openssh_forwardedStreamLocal(
        localChan, initWindow, maxPacket, opts
      );
      break;
    default:
      throw new Error(`Unsupported channel type: ${type}`);
  }
}

function compareNumbers(a, b) {
  return a - b;