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JCOSkip.java

package edu.virtualschool.jco.unfinished;

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.math.BigInteger;
import java.net.ServerSocket;
import java.net.Socket;
import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.Provider;
import java.security.PublicKey;
import java.security.Security;
import java.security.spec.X509EncodedKeySpec;

import javax.crypto.KeyAgreement;
import javax.crypto.spec.DHParameterSpec;

import org.bouncycastle.jce.provider.BouncyCastleProvider;

import edu.virtualschool.jco.JCOBase64;
import edu.virtualschool.jwaa.IntervalTimer;

public class JCOSkip
{
    
  private static final BigInteger skipP = new BigInteger(
    "f488fd584e49dbcd20b49d349107366b336c380d451d0f7c88b31c7c5b2d8ef6"+
    "f3c923c043f0a55b188d8ebb558cb85d38d334fd7c175743a31d186cde33212c"+
    "b52aff3ce1b1294018118d7c84a70a72d686c40319c807297aca950cd9968fab"+
    "d00a509b0246d3083d66a45d419f9c7cbd894b221926baaba25ec355e92f78c7", 16);

  private static final BigInteger skipG = BigInteger.valueOf(2);

  private static final DHParameterSpec skipParams = 
    new DHParameterSpec(skipP, skipG);
  
  public static void main(String[] args) throws Exception
  {
    Server.main(new String[] { "8081" });
    Client.main(new String[] {"localhost", "8081"});
    return;
  }
  public static class Server
  {
    final private KeyPair keyPair;
    final private DataOutputStream out;
    final private DataInputStream in;

    private final static Provider provider = new BouncyCastleProvider();
    static  { Security.addProvider(provider); }
    
    public static void main(String[] args) throws Exception
    {
      int port = Integer.parseInt(args[0]);
      Server server = new Server(port);
      byte[] secret = server.getSecretKey();
      System.out.println("Server secret:"+JCOBase64.encode(secret));
    }
    public Server(int port) throws Exception
    {
      KeyPairGenerator kpg = KeyPairGenerator.getInstance("DH");
      kpg.initialize(skipParams);
      this.keyPair = kpg.genKeyPair();
      
      // Wait for network connection
      ServerSocket ss = new ServerSocket(port);
      System.out.println("Listening on port " + port);
      Socket s = ss.accept();
      
      this.out = new DataOutputStream(s.getOutputStream());
      this.in = new DataInputStream(s.getInputStream());
    }
    public byte[] getSecretKey() throws Exception
    {
      // Receive their public key
      int theirLength = in.readInt();
      byte[] theirBytes = new byte[theirLength];
      in.readFully(theirBytes);
      KeyFactory kf = KeyFactory.getInstance("DH", "BC");
      X509EncodedKeySpec x509Spec = new X509EncodedKeySpec(theirBytes);
      PublicKey theirPublicKey = kf.generatePublic(x509Spec);
      
      // Respond with my public key
      byte[] myBytes = keyPair.getPublic().getEncoded();
      out.writeInt(myBytes.length);
      out.write(myBytes);
      
      // Generate shared secret
      IntervalTimer t = new IntervalTimer();
      KeyAgreement ka = KeyAgreement.getInstance("DH", "BC");
      System.err.println("Server ka=KeyAgreement msec: "+t);
      ka.init(keyPair.getPrivate());
      System.err.println("Server ka.init msec: "+t);
      ka.doPhase(theirPublicKey, true);
      System.err.println("Server ka.doPhase msec: "+t);
      byte[] secret = ka.generateSecret();
      System.err.println("Server ka.generateSecret msec: "+t);
      
      // Clean up
      out.close();
      in.close();
      return secret;
    }
  }
  public static class Client
  {
    final private KeyPair keyPair;
    final private DataOutputStream out;
    final private DataInputStream in;

    private final static Provider provider = new BouncyCastleProvider();
    static  { Security.addProvider(provider); }
    
    public static void main(String[] args) throws Exception
    {
      String host = args[0];
      int port = Integer.parseInt(args[1]);
      Client client = new Client(host, port);
      byte[] secret = client.getSecretKey();
      System.out.println("Client secret: " + JCOBase64.encode(secret));
    }
    public Client(String host, int port) throws Exception
    {
      // Create Diffie-Hellman key pair
      KeyPairGenerator kpg = KeyPairGenerator.getInstance("DH", "BC");
      kpg.initialize(skipParams);
      this.keyPair = kpg.genKeyPair();

      // Open the network connection
      Socket s = new Socket(host, port);
      this.out = new DataOutputStream(s.getOutputStream());
      this.in = new DataInputStream(s.getInputStream());
    }
    public byte[] getSecretKey() throws Exception
    {
      // Send my public key
      byte[] myBytes = keyPair.getPublic().getEncoded();
      out.writeInt(myBytes.length);
      out.write(myBytes);
      
      // Receive their public key
      byte[] theirBytes = new byte[in.readInt()];
      in.readFully(theirBytes);
      KeyFactory kf = KeyFactory.getInstance("DH", "BC");
      X509EncodedKeySpec theirSpec = new X509EncodedKeySpec(theirBytes);
      PublicKey theirPublicKey = kf.generatePublic(theirSpec);
      
      // Generate the secret value
      IntervalTimer t = new IntervalTimer();
      KeyAgreement ka =KeyAgreement.getInstance("DH", "BC");
      System.err.println("Client ka=KeyAgreement.getInstance: "+t);
      ka.init(keyPair.getPrivate());
      System.err.println("Client ka.init: "+t);
      ka.doPhase(theirPublicKey, true);
      System.err.println("Client ka.doPhase: "+t);
      byte[] secret = ka.generateSecret();
      System.err.println("Client ka.generateSecret: "+t);
      
      // Clean up
      out.close();
      in.close();
      return secret;
    }
  }
}
//Listening on port 8765
//Server ka=KeyAgreement msec: 6677
//Server ka.init msec: 14
//Server ka.doPhase msec: 503
//Server ka.generateSecret msec: 1
//Server secret:AItNLhor/hXuYq0uyGykIHaBv+4Yjul0eU224Lc55ISayBq1GZ5/jpruaRLeiad6846qyh16vE52x/i3K7/dmYqQIY3iAhTKS/JQs5jZjhjfib2K/shzQGK1dnkA2pIYMQhWP5YOjz5zK3VGbg1QYA8BIraS0Or3+02nE/aNlmp9
//
//Client ka=KeyAgreement.getInstance: 6696
//Client ka.init: 13
//Client ka.doPhase: 381
//Client ka.generateSecret: 1
//Client secret: AItNLhor/hXuYq0uyGykIHaBv+4Yjul0eU224Lc55ISayBq1GZ5/jpruaRLeiad6846qyh16vE52x/i3K7/dmYqQIY3iAhTKS/JQs5jZjhjfib2K/shzQGK1dnkA2pIYMQhWP5YOjz5zK3VGbg1QYA8BIraS0Or3+02nE/aNlmp9