Ensure that idle sockets are automatically closed.

client.js

@@ -1,5 +1,7 @@
 'use strict';
 
+const IDLE_SOCKET_TIMEOUT_MILLISECONDS = 1000 * 30;
+
 module.exports = (options) => {
   return new Promise((resolve, reject) => {
     // require the things we need
@@ -50,6 +52,11 @@ module.exports = (options) => {
         ss(socket).emit(clientId, s);
       });
 
+      client.setTimeout(IDLE_SOCKET_TIMEOUT_MILLISECONDS);
+      client.on('timeout', () => {
+        client.end();
+      });
+
       client.on('error', () => {
         // handle connection refusal (create a stream and immediately close it)
         let s = ss.createStream();

server.js

@@ -112,11 +112,6 @@ module.exports = (options) => {
         // Pipe all data from tunnel stream to requesting connection
         tunnelClientStream.pipe(req.connection);
 
-        // ensure that we kill the remote socket if the http connection drops
-        req.connection.on('end', () => {
-          tunnelClientStream.destroy();
-        });
-
         resolve(tunnelClientStream);
       });