c# decryption [Java Encryption]

Hi all,

I'm pretty new to Encryption/Decryption and I have been struggling for the last 2 days trying to decrypt data encrypted in Java.

From my understanding, the following java code use DES mode ECB with PKCS5Padding for Padding.

The key is: 7IC64w6ksLU

The value to decode is: cy0vlmQq8RIc3lalnjPKpA==

The java encryption script is the following:

import java.security.MessageDigest;

import java.util.Arrays;

import javax.crypto.Cipher;

import javax.crypto.KeyGenerator;

import javax.crypto.SecretKey;

import javax.crypto.SecretKeyFactory;

import javax.crypto.spec.DESKeySpec;

import javax.crypto.spec.IvParameterSpec;

import javax.crypto.spec.SecretKeySpec;

import org.apache.commons.codec.binary.Base64;

import org.apache.commons.lang.StringUtils;

 

 

public String ALGORITHM = "DES/ECB/PKCS5Padding";

public String HASH_ALGORITHM = "SHA";

 

public String CHARSET = "UTF-8";

 

private SecretKey desKey;

private FieldHelper encrypted = null;

 

public boolean processRow(StepMetaInterface smi, StepDataInterface sdi) throws KettleException

{

    

    Object[] r = getRow();

 

    if (r == null) {

        setOutputDone();

        return false;

    }

 

    if (first){

        first = false;

try {

                                setSecretKey("7IC64w6ksLU");

}

catch (Exception e) {

            throw new RuntimeException(e);

        }

    }

 

    r = createOutputRow(r, data.outputRowMeta.size());

 

    // Get the value from an input field

    String test_value = get(Fields.In, "vht_tax_number").getString(r);

 

    // play around with it

if(test_value != null) {

                String regexed=test_value.replaceAll("[^0-9]","");

    String Encrypted = encrypt(regexed);

 

    // Set a value in a new output field

    get(Fields.Out, "encrypted").setValue(r, Encrypted);

} else {

get(Fields.Out, "encrypted").setValue(r, test_value);

}

 

    // Send the row on to the next step.

    putRow(data.outputRowMeta, r);

 

    return true;

}

public String encrypt(Object valueToHide)  {

               

               

        if (valueToHide == null) {

            return "";

        }

try {

        // Initialize the cipher for encryption

        Cipher cipher = Cipher.getInstance(ALGORITHM);

        cipher.init(Cipher.ENCRYPT_MODE, desKey);

 

      

            // Our cleartext

            byte[] cleartext = valueToHide.toString().getBytes(CHARSET);

   

            // Encrypt the cleartext

            byte[] ciphertext = cipher.doFinal(cleartext);

   

            return new String(Base64.encodeBase64(ciphertext), CHARSET);

        }

                                catch (Exception e) {

            throw new RuntimeException(e);

        }

   }

private SecretKey unwrapEncodedKey(String key) throws Exception {

        KeyGenerator keygen = KeyGenerator.getInstance("DES");

        SecretKey desKey = keygen.generateKey();

 

        // Create the cipher

        Cipher cipher = Cipher.getInstance(ALGORITHM);

        cipher.init((Cipher.UNWRAP_MODE), desKey);

 

        byte[] bytes = Base64.decodeBase64(key.getBytes());

 

        SecretKeyFactory desFactory = SecretKeyFactory.getInstance("DES");

 

        DESKeySpec keyspec = new DESKeySpec(bytes);

        SecretKey k = desFactory.generateSecret(keyspec);

 

        return k;

 

    }

public void setSecretKey(String secretKey) throws Exception {

                if (!StringUtils.isEmpty(secretKey)) {

                                desKey = this.unwrapEncodedKey(secretKey);

                               

                                // Create the cipher

                                Cipher cipher = Cipher.getInstance(ALGORITHM);

                                cipher.init((Cipher.WRAP_MODE), desKey);

                }

    }

My C# decryption code is the following:

using System;
using System.Security.Cryptography;
using System.Text;
using System.IO;

class ConsoleApplication3
{
    static void Main(string[] args)
    {
        try
        {
            // Create a new TripleDESCryptoServiceProvider object
            // to generate a key and initialization vector (IV).
            DESCryptoServiceProvider tDESalg = new DESCryptoServiceProvider();
            tDESalg.Mode = CipherMode.ECB;
            //tDESalg.Padding = PaddingMode.PKCS7;
            tDESalg.GenerateKey();
            //byte[] key = tDESalg.Key;

            //Console.Write("Generated key: \n");
            //foreach(byte b in key){
            //    Console.Write(b + "\n");
            //}

            //Console.Write("\n\n");
            tDESalg.Key = System.Convert.FromBase64String("71C64w6ksLU=");

            // Decrypt the buffer back to a string.
            string Final = DecryptTextFromMemory(System.Convert.FromBase64String("cy0vlmQq8RIc3lalnjPKpA=="), tDESalg.Key, tDESalg.IV);

            // Display the decrypted string to the console.
            Console.WriteLine(Final);
            Console.WriteLine("Press any key to exit.");
            Console.ReadKey();
        }
        catch (Exception e)
        {
            Console.WriteLine(e.Message);
        }

    }

    public static string DecryptTextFromMemory(byte[] Data,  byte[] Key, byte[] IV)
    {
        try
        {
            // Create a new MemoryStream using the passed  
            // array of encrypted data.
            MemoryStream msDecrypt = new MemoryStream(Data);

            // Create a CryptoStream using the MemoryStream  
            // and the passed key and initialization vector (IV).
            CryptoStream csDecrypt = new CryptoStream(msDecrypt,
                new DESCryptoServiceProvider().CreateDecryptor(Key, IV),
                CryptoStreamMode.Read);

            
            // Create buffer to hold the decrypted data.
            byte[] fromEncrypt = new byte[Data.Length];

            // Read the decrypted data out of the crypto stream
            // and place it into the temporary buffer.
            csDecrypt.Read(fromEncrypt, 0, fromEncrypt.Length);

            //Convert the buffer into a string and return it.
            return new ASCIIEncoding().GetString(fromEncrypt);
            //String res =  System.Convert.ToBase64String(fromEncrypt);
            //return res;
        }
        catch(CryptographicException e)
        {
            Console.WriteLine("A Cryptographic error occurred: {0}", e.Message);
            return null;
        }
    }
}

Please let me know if you have any suggestion for decrypting this value. I can't point out what I am doing wrong.

Regards,

Greg