MainClass.java Source code

Introduction

Here is the source code for MainClass.java

Source

import java.math.BigInteger;
import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.SecureRandom;

import javax.crypto.spec.DHParameterSpec;
import javax.crypto.spec.DHPublicKeySpec;

public class MainClass {
    public final static int pValue = 47;

    public final static int gValue = 71;

    public final static int XaValue = 9;

    public final static int XbValue = 14;

    public static void main(String[] args) throws Exception {
        BigInteger p = new BigInteger(Integer.toString(pValue));
        BigInteger g = new BigInteger(Integer.toString(gValue));
        BigInteger Xa = new BigInteger(Integer.toString(XaValue));
        BigInteger Xb = new BigInteger(Integer.toString(XbValue));

        createKey();

        int bitLength = 512; // 512 bits
        SecureRandom rnd = new SecureRandom();
        p = BigInteger.probablePrime(bitLength, rnd);
        g = BigInteger.probablePrime(bitLength, rnd);

        createSpecificKey(p, g);
    }

    public static void createKey() throws Exception {
        KeyPairGenerator kpg = KeyPairGenerator.getInstance("DiffieHellman");

        kpg.initialize(512);
        KeyPair kp = kpg.generateKeyPair();
        KeyFactory kfactory = KeyFactory.getInstance("DiffieHellman");

        DHPublicKeySpec kspec = (DHPublicKeySpec) kfactory.getKeySpec(kp.getPublic(), DHPublicKeySpec.class);
    }

    public static void createSpecificKey(BigInteger p, BigInteger g) throws Exception {
        KeyPairGenerator kpg = KeyPairGenerator.getInstance("DiffieHellman");

        DHParameterSpec param = new DHParameterSpec(p, g);
        kpg.initialize(param);
        KeyPair kp = kpg.generateKeyPair();

        KeyFactory kfactory = KeyFactory.getInstance("DiffieHellman");

        DHPublicKeySpec kspec = (DHPublicKeySpec) kfactory.getKeySpec(kp.getPublic(), DHPublicKeySpec.class);
    }
}