IRC: No Ident response

Question

I am currently working on a IRC client written in Java.

As soon as the connection to the server is established I send these messages:

• /NICK test
• /JOIN #chat

The first tests went pretty well - the server is responding. But every time it says:

• NOTICE AUTH :***
• Checking Ident
• NOTICE AUTH :***
• No Ident response
• ERROR :Closing Link ... (Registration timed out)

I found a related question that helped a little bit. It says I need to listen on port 113 for a connection and a message to receive and respond to from the IRC-Server. I implemented a ServerSocket that listens on that port, but the server doesn't try to open a connection on port 113. What am I doing wrong?

Heres the code:

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.net.ServerSocket;
import java.net.Socket;

public class IdentProtocolThread extends Thread {

private String nick;
private ServerSocket serverSocket;
private BufferedReader reader;
private BufferedWriter writer;

public IdentProtocolThread(String nick) throws IOException {
    this.nick = nick;

    this.serverSocket = new ServerSocket(113);
}

@Override
public void run() {

    try {

        System.out.println("waiting for incoming socket");
        Socket socket = this.serverSocket.accept();

        System.out.println("socket accepted");
        this.initialize(socket);
        System.out.println("reader/writer initialized");

        String line = null;
        while ((line = this.reader.readLine()) != null) {
            System.out.println(line);
        }

    } catch (IOException e) {
        e.printStackTrace();
    }
    System.out.println("done");
}

private void initialize(Socket socket) throws IOException {
    this.reader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
    this.writer = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream()));
}
}

On execution I only get this displayed:

waiting for incoming socket

Do I need to send some other messages to avoid the ident check?

Answer 1

Have a look at this question for references to the underlying IRC protocol; it is somewhat more structured than the /-commands you're used to seeing in a client. The handshake often looks something like this:

<< USER foo . . :real name
<< NICK bar
>> :server PING somethinglonghere
<< PONG :somethinglonghere
>> :server 001 bar :Welcome!
<< JOIN #channel
>> :bar!foo@yourhost JOIN #channel
>> :server 332 bar #channel :channel topic
>> :server 353 bar = #channel :@someop +somevoice someuser anotheruser
>> :server 366 bar #channel :End of /NAMES list

where << indicates a line of text sent to the server and >> indicates a line of text received from the server. Note also that IRC nominally uses \r\n line endings, though a number of servers will accept \n too.