Java安全套接字数据传输/接收器

Question

I have build up a Chat application, and I'm using PrintWriter and Scanner to read and write to stream. For example:

Socket socket = new Socket(HOST, PORT);
Scanner IN = new Scanner(socket.getInputStream());
PrintWriter OUT = new PrintWriter(socket.getOutputStream());
String MESSAGE = "";

while(true){
 if(IN.hasNext()){
    MESSAGE = IN.nextLine();
    OUT.println("RESPONSE: " + MESSAGE);
    OUT.flush();
 }
}

I have thinking about what if somebody connects to my server (ServerSocket), he could read all data what have I write to stream. The worst case it would be if he writes to the stream.

I was thinking about encryption. All data would be encrypted and the "RECEIVER" would decrypt data stream. Also, I must use a secured key, in the beginning or at the end of the encrypted string that would be written to the stream. And if the secured key is valid, the string will be allowed to be read by the receiver.

Is this a good solution? Is this enough secured? It is good enough to use PrinterWriter and Scanner to read/write to a stream? What about InputStreamReader and BufferedStream?

Answer 1

I would advice you not create the socket server from scratch as you are attempting. Use Netty (or even Apache mina) to do this. Netty has built-in support for SSL and you can setup client-side certificates. If you are unwilling to take on the extra work of SSL, then you can implement IP based restrictions or add a simple password into your protocol coupled with SSL.

For more information: http://netty.io