public static void main(String[] args) throws IOException {
/*
Requirements:
- BigInteger and SecureRandom should be used
- p and q should be at least 512-bit
- difference between p and q should be bigger than 2^256
- demonstration of encryption and decryption should be given
- should include encryption and decryption timing
- public key e is 65537
*/
RSA rsa = new RSA();
int plainText;
BigInteger b_plainText, b_cipherText;
int e_start, e_end, encryptTime, d_start, d_end, decryptTime;
if (args.length != 0 && args[0].equalsIgnoreCase("n")) {
System.out.println("Plaintext chosen for you");
plainText = 1325975912;
} else {
System.out.println("Enter a number (string characters not allowed): ");
Scanner StdIn = new Scanner(System.in);
plainText = StdIn.nextInt();
}
b_plainText = BigInteger.valueOf(plainText);
e_start = (int) System.nanoTime();
b_cipherText = rsa.encrypt(b_plainText);
e_end = (int) System.nanoTime();
System.out.println("plaintext:\t" + b_plainText.toString());
System.out.println("ciphertext:\t" + b_cipherText.toString());
d_start = (int) System.nanoTime();
b_plainText = rsa.decrypt(b_cipherText);
d_end = (int) System.nanoTime();
System.out.println("plaintext after decryption:\t" + b_plainText.toString());
encryptTime = e_end - e_start;
decryptTime = d_end - d_start;
System.out.println(
"encryption time (ns): "
+ String.valueOf(encryptTime)
+ ", decryption time (ns): "
+ String.valueOf(decryptTime));
}
public static void main(String[] args) {
RSA myRSA = new RSA();
String text = "Ὅσον ζῇς φαίνου";
System.out.println(text);
System.out.println(myRSA.decrypt(myRSA.encrypt(text, myRSA.getPublicKey())));
}