cipher.java

RSA编码与解码

/**
 * 
 */
package RSA;

import java.math.BigInteger;

/**
 * @author Administrator
 *
 */
public class Cipher {
	public BigInteger PublicKey;
	public BigInteger PrimeP;
	public BigInteger PrimeQ;
	public BigInteger PrimeN;
	public BigInteger ThetaN;
	public BigInteger SecretKey;
	
	public Cipher(){}
	
	public void init(BigInteger primep, BigInteger primeq, BigInteger publickey)
	{
		this.PublicKey = publickey;
		this.PrimeP = primep;
		this.PrimeQ = primeq;
		SetThetaN();
		SetPrimeN();
		ComputeSecretKey();
	}

	public void SetPrimeN()
	{
		this.PrimeN = this.PrimeP.multiply(this.PrimeQ);
	}
	
	public void SetThetaN()
	{
		BigInteger thetaN = (this.PrimeP.add(new BigInteger("-1"))).multiply((this.PrimeQ.add(new BigInteger("-1"))));
		this.ThetaN = thetaN;
	}
	
	public void ComputeSecretKey()
	{
		this.SecretKey = (this.PublicKey).modInverse(this.ThetaN);
		System.out.println("\nThe SecretKey Value d ="+this.SecretKey);
	}
}