bsidessf-pinlock.java

// rename as HelloWorld.java :)

import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Arrays;
import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.PBEKeySpec;
import javax.crypto.spec.SecretKeySpec;
import sun.misc.BASE64Decoder;

public class HelloWorld{

public static void main(String[] args) throws Exception
{ 
  String SECRET = "Bi528nDlNBcX9BcCC+ZqGQo1Oz01+GOWSmvxRj7jg1g=";

  Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
  byte[] salt = "SampleSalt".getBytes();
  String pin = "7498";
  SecretKeySpec key = new SecretKeySpec(SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1").generateSecret(new PBEKeySpec(pin.toCharArray(), salt, 1000, 128)).getEncoded(), "AES");
  cipher.init(2,key);
  BASE64Decoder decoder = new BASE64Decoder();
  System.out.println(new String(cipher.doFinal(decoder.decodeBuffer(SECRET)),"UTF-8")); 
}

}