RSADemo.java

/*
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 * Click nbfs://nbhost/SystemFileSystem/Templates/Classes/Class.java to edit this template
 */
package week03;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.math.BigInteger;
/**
 *
 * @author levan
 */
public class RSADemo {
    public static void main(String[] args) throws IOException {
        int primeSize = 1024;
        RSACipher rsa = new RSACipher(primeSize);
        System.out.println("Key Size: [" + primeSize + "]");
        System.out.println(); 
        System.out.println("Generated prime numbers p and q");
        System.out.println("p: (" + rsa.getP().toString(16).toUpperCase() + "]");
        System.out.println("q: ("+ rsa.getQ().toString(16).toUpperCase() + "]"); 
        System.out.println();
        System.out.println("The public key is the pair (N, E) which will be published."); 
        System.out.println("N: [" + rsa.getN().toString(16).toUpperCase() + "]");
        System.out.println("E: [" + rsa.getE().toString(16).toUpperCase() + "]");
        System.out.println();
        System.out.println("The private key is the pair (N, D) which will be kept private."); 
        System.out.println("N: ("+ rsa.getN().toString(16).toUpperCase() + "]"); 
        System.out.println("D: [" + rsa.getD().toString(16).toUpperCase() + "]"); 
        System.out.println(); 
        System.out.print("Please enter message (plaintext): "); 
        String plaintext = new BufferedReader(new InputStreamReader(System.in)).readLine(); 
        BigInteger[] ciphertext= rsa.encrypt (plaintext); 
        System.out.print("Ciphertext: "); 
        for (BigInteger ciphertextPart: ciphertext) {
                System.out.print(ciphertextPart.toString(16).toUpperCase());
                System.out.print(""); 
                }
        System.out.println();
        String recoveredPliantext = rsa.decrypt(ciphertext, rsa.getD(), rsa.getN());
        System.err.println("Recovered plaintext: "+ recoveredPliantext);
        
    }
    
}