MainClass.java Source code

Introduction

Here is the source code for MainClass.java

Source

import java.math.BigInteger;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.MessageDigest;
import java.security.SecureRandom;
import java.security.Security;
import java.security.spec.ECFieldFp;
import java.security.spec.ECParameterSpec;
import java.security.spec.ECPoint;
import java.security.spec.EllipticCurve;

import javax.crypto.KeyAgreement;

public class MainClass {
    public static void main(String[] args) throws Exception {
        Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());

        KeyPairGenerator keyGen = KeyPairGenerator.getInstance("ECDH", "BC");
        EllipticCurve curve = new EllipticCurve(
                new ECFieldFp(new BigInteger("fffffffffffffffffffffffffffffffeffffffffffffffff", 16)),
                new BigInteger("fffffffffffffffffffffffffffffffefffffffffffffffc", 16),
                new BigInteger("fffffffffffffffffffffffffffffffefffffffffffffffc", 16));

        ECParameterSpec ecSpec = new ECParameterSpec(curve,
                new ECPoint(new BigInteger("fffffffffffffffffffffffffffffffefffffffffffffffc", 16),
                        new BigInteger("fffffffffffffffffffffffffffffffefffffffffffffffc", 16)),
                new BigInteger("fffffffffffffffffffffffffffffffefffffffffffffffc", 16), 1);

        keyGen.initialize(ecSpec, new SecureRandom());

        KeyAgreement aKeyAgree = KeyAgreement.getInstance("ECDH", "BC");
        KeyPair aPair = keyGen.generateKeyPair();
        KeyAgreement bKeyAgree = KeyAgreement.getInstance("ECDH", "BC");
        KeyPair bPair = keyGen.generateKeyPair();

        aKeyAgree.init(aPair.getPrivate());
        bKeyAgree.init(bPair.getPrivate());

        aKeyAgree.doPhase(bPair.getPublic(), true);
        bKeyAgree.doPhase(aPair.getPublic(), true);

        MessageDigest hash = MessageDigest.getInstance("SHA1", "BC");

        System.out.println(new String(hash.digest(aKeyAgree.generateSecret())));
        System.out.println(new String(hash.digest(bKeyAgree.generateSecret())));
    }
}