Restrict java-websocket access to localhost

Question

I'm writing a java-websocket server as a cryptocurrency client.

For security reasons, I'd like to restrict access to the local machine.

Is there a way to restrict access to a java-websocket server by IP or hostname?

If so, how?

Answer 1

You should specify your listening ip to 127.0.0.1 thus it wont be possible to connect from the outside.

Edit

Looking at the example ChatServer.java the binding happens with

ChatServer s = new ChatServer( port );

The class implements two constructors:

  public ChatServer( int port ) throws UnknownHostException {
            super( new InetSocketAddress( port ) );
    }

    public ChatServer( InetSocketAddress address ) {
            super( address );
    }

So you could also call the server with an inetSocketAddress. Create one thats binds to localhost:

new ServerSocket(9090, 0, InetAddress.getByName(null));

and then call the server with that instead of just the port.

So replace

ChatServer s = new ChatServer( port );

with

InetSocketAddress myLocalSocket = new ServerSocket(9090, 0, InetAddress.getByName(null));
ChatServer s = new ChatServer( myLocalSocket );

in your example and it should work.