TLS Without Certificates

TlsWithoutCertificatesDemo.java

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.net.Socket;
import java.util.Arrays;
import java.util.LinkedHashSet;
import java.util.Set;

import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLServerSocket;
import javax.net.ssl.SSLServerSocketFactory;
import javax.net.ssl.SSLSocket;
import javax.net.ssl.SSLSocketFactory;

final class Server
{
  public static void main(String[] arstring) throws Throwable
  {
    SSLContext sslContext = SSLContext.getDefault();
    SSLServerSocketFactory sslServerSocketFactory = sslContext.getServerSocketFactory();

    try (SSLServerSocket sslServerSocket = (SSLServerSocket) sslServerSocketFactory.createServerSocket(9999))
    {
      String[] supportedAnonCipherSuites = Util
          .getSupportedAnonCipherSuites(sslServerSocket.getSupportedCipherSuites());
      sslServerSocket.setEnabledCipherSuites(supportedAnonCipherSuites);

      try (Socket socket = sslServerSocket.accept())
      {
        BufferedReader br = new BufferedReader(new InputStreamReader(socket.getInputStream()));

        for (String line; (line = br.readLine()) != null;)
          System.out.println(line);
      }
    }
  }
}

final class Client
{
  public static void main(String[] arstring) throws Throwable
  {
    SSLContext sslContext = SSLContext.getDefault();
    SSLSocketFactory sslSocketFactory = sslContext.getSocketFactory();

    try (SSLSocket sslSocket = (SSLSocket) sslSocketFactory.createSocket("localhost", 9999))
    {
      String[] supportedAnonCipherSuites = Util
          .getSupportedAnonCipherSuites(sslSocket.getSupportedCipherSuites());
      sslSocket.setEnabledCipherSuites(supportedAnonCipherSuites);

      System.out.println("Connected to server");

      System.out.printf("Enter your input: ");
      BufferedReader userInput = new BufferedReader(new InputStreamReader(System.in));
      BufferedWriter bufferedwriter = new BufferedWriter(new OutputStreamWriter(sslSocket.getOutputStream()));
      for (String input; (input = userInput.readLine()) != null;)
      {
        System.out.println("Sending input: " + input);
        bufferedwriter.append(input).append('\n').flush();
        System.out.println("Your input is sent");
        System.out.printf("Enter your input: ");
      }
    }
  }
}

final class Util
{
  private static final Set<String> ANON_CIPHER_SUITES = new LinkedHashSet<>(Arrays.asList(
      "TLS_DH_anon_WITH_AES_256_GCM_SHA384",
      "TLS_DH_anon_WITH_AES_128_GCM_SHA256",
      "TLS_DH_anon_WITH_AES_256_CBC_SHA256",
      "TLS_DH_anon_WITH_AES_128_CBC_SHA256",
      "TLS_ECDH_anon_WITH_AES_128_CBC_SHA",
      "TLS_DH_anon_WITH_AES_128_CBC_SHA"));

  static String[] getSupportedAnonCipherSuites(String[] supportedCipherSuites)
  {
    Set<String> cipherSuites = new LinkedHashSet<>(Arrays.asList(supportedCipherSuites));
    cipherSuites.retainAll(ANON_CIPHER_SUITES);
    if (cipherSuites.isEmpty())
      throw new RuntimeException("No predefined anon Cipher Suiters are supported");
    return cipherSuites.toArray(new String[cipherSuites.size()]);
  }
}