Problem with DES Decryption of String - Need Urgent Help

Question

Hi,
I created this program to encrypt and decrypt a string using DES algorithm but somehow I keep getting an exception. The code is given below.
/* ASCryptography.java*/
import javax.crypto.*;
import javax.crypto.spec.*;
import java.security.*;
import java.io.*;
import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;
public class ASCryptography
     public static String[] encryptPassword(String password)
          String returnvalue[] = new String[2];
          try
               KeyGenerator keygen = KeyGenerator.getInstance("DES");
               SecretKey skey = keygen.generateKey();
               byte[] bytekey = skey.getEncoded();
               returnvalue[0] = new BASE64Encoder().encode(bytekey);
               Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");
               cipher.init(Cipher.ENCRYPT_MODE, skey);
               byte[] bytepassword = password.getBytes();
               byte[] byteencryptedpassword = cipher.doFinal(bytepassword);
               returnvalue[1] = new BASE64Encoder().encode(byteencryptedpassword);
          catch(Exception err)
          return (returnvalue);
     public static String decryptPassword(String key, String encryptedpassword)
          String password = null;
          try
               Cipher decipher = Cipher.getInstance("DES/CBC/PKCS5Padding");               
               byte[] bytekey = new BASE64Decoder().decodeBuffer(key);
               SecretKey skey = new SecretKeySpec(bytekey, "DES");
               decipher.init(Cipher.DECRYPT_MODE, skey, decipher.getParameters());   /* Netbeans detected the error to be in this part*/
               byte[] byteencryptedpassword = new BASE64Decoder().decodeBuffer(encryptedpassword);
               byte[] bytedecryptedpassword = decipher.doFinal(byteencryptedpassword);
               password = new String(bytedecryptedpassword);
          catch(Exception err)
               System.out.println(err);
          return password;
}The methods of this class are used by another class given below.
/*Crypt.java*/
public class Crypt
     public static void main(String[] args)
          String password = "pic01234";
          String value[] = new String[2];
          value = ASCryptography.encryptPassword(password);
          System.out.println(value[0]);
          System.out.println(value[1]);
          String returnedvalue = ASCryptography.decryptPassword(value[0], value[1]);
          System.out.println(returnedvalue); //the returned value remains null
          System.out.println(returnedvalue.length()); // This generates a null pointer exception coz of above.
}Now whenever I run the Crypt.java program the Netbeans IDE gives the following as output
jL+Fg2EBp9Y=
LOhqKHoJRkKWc76IkU4q/A==
java.security.InvalidAlgorithmParameterException: Parameters missing
null
Exception in thread "main" java.lang.NullPointerException
I used the Step in tool of Netbeans and came out with the following conclusion
1. The first 2 strings are the encrypted key and the password string so encryption is working fine.
2. All is fine till the decipher.init(Cipher.DECRYPT_MODE, skey, decipher.getParameters()); part is encountered at this point the java.security.InvalidAlgorithmParameterException: Parameters missing is thrown.
3.The NullPointerException is caused due to the null value stored in returnedvalue
Can anyone help me out with this one I have been trying to solve for the past 6 hours.
Thanks!

Answer 1

Also -
1) Using an array to return a compound result is at best poor. You should really define a class as a container for your encryption result.
2) Since you generate and return a new key for each password, where are you going to store the key. If you store it in the same place (database ?) as the encrypted password then this is just the same as not encrypting the password because anyone with with access to the encrypted password will also have access to the key!