Comments on BlueSam Blog: Triple DES Encryption implementation compatible be...

Hi Sam, My knowledge on the whole encryption bit ...

2010-08-24T14:44:25.883-07:00

Hi Sam,

My knowledge on the whole encryption bit is very poor. We recieve a java generated Triple DES key from a third party. I want to encrypt/decrypt the key in our VB.NET app. Do we have to modify both the .NET and the Java code?
Please pardon my ignorance but vould you please tell me how do i use the key in my app.

Like when i use the key in this line of code:
Dim desTransform As ICryptoTransform = desCrypto.CreateEncryptor(EncryptKey(Key), EncryptIV(IV))

I get the error: 'specified key is not a valid size for this algorithm'.

Could you show me how to use the key here.

Thanks.

Thank you very much. This really helped me out.

2010-07-05T18:01:20.192-07:00

Thank you very much. This really helped me out.

hi. is it possible in both .net and java sides so ...

2010-05-06T19:44:48.289-07:00

hi. is it possible in both .net and java sides so create a key and IV according to our own preferred string?

rather than be restricted to 24 bytes and 8 bytes respectively?

have modified the java code somewhat, but it works...

2010-02-04T00:26:18.370-08:00

have modified the java code somewhat, but it works fine for me, I encrypting the string in .net and decrypting it on java... hope it'll be helpful for you.

package com.bay.bizlogic;

/**
* Created by Nitin Gaur.
* User: admin
* Date: 4 Feb, 2010
* Time: 12:46:23 PM
* To change this template use File | Settings | File Templates.
*/
import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

public class TripleDES {
private String key;
private String initializationVector;
public TripleDES(String key, String initializationVector)
{
this.key = key;
this.initializationVector = initializationVector;

}

public String encryptText(String plainText) throws Exception{
//---- Use specified 3DES key and IV from other source --------------
byte[] plaintext = plainText.getBytes();
byte[] tdesKeyData = key.getBytes();

// byte[] myIV = initializationVector.getBytes();

Cipher c3des = Cipher.getInstance("DESede/CBC/PKCS5Padding");
SecretKeySpec myKey = new SecretKeySpec(tdesKeyData, "DESede");
IvParameterSpec ivspec = new IvParameterSpec(initializationVector.getBytes());

c3des.init(Cipher.ENCRYPT_MODE, myKey, ivspec);
byte[] cipherText = c3des.doFinal(plaintext);

return new sun.misc.BASE64Encoder().encode(cipherText);
}
public String decryptText(String cipherText)throws Exception{
byte[] encData = new sun.misc.BASE64Decoder().decodeBuffer(cipherText);
Cipher decipher = Cipher.getInstance("DESede/CBC/PKCS5Padding");
byte[] tdesKeyData = key.getBytes();
SecretKeySpec myKey = new SecretKeySpec(tdesKeyData, "DESede");
IvParameterSpec ivspec = new IvParameterSpec(initializationVector.getBytes());
decipher.init(Cipher.DECRYPT_MODE, myKey, ivspec);
byte[] plainText = decipher.doFinal(encData);
return new String(plainText);
}
}

Thanks...
India

Sam, THANK YOU VERY MUCH!!! This is 75% of what I ...

2010-01-05T09:42:20.720-08:00

Sam,
THANK YOU VERY MUCH!!! This is 75% of what I have been looking high and low for. Can you please post the Java Decryptor function for the remaining 25% of the functionality I need??? I am not a java developer, so am having a hard time with this.
Thanks a lot for this great post...

So Many Thank Thank Thank. Very good topic

2009-10-14T23:03:37.132-07:00

So Many Thank Thank Thank.

Very good topic

Sam - thanks, I found it in the article you origin...

2009-08-27T12:30:15.880-07:00

Sam - thanks, I found it in the article you originally referenced. The problem is that Java requires a 24 byte key; so I needed to take the 16 byte password, and pad with the first 8 bytes of the password. now it works like a champ!

cawineguy, I'm afraid I'm not much of a ja...

2009-08-26T21:29:41.651-07:00

cawineguy, I'm afraid I'm not much of a java expert, so I'm afraid I can't tell you what's going on right off the bat. I'll take a look at it and get back to you if I find anything.

When I found this post I got excited, because this...

2009-08-26T11:38:11.602-07:00

When I found this post I got excited, because this is precisely the problem I'm trying to solve, except the other direction. Here is the .NET code I want to convert to java:
Decryptor dec = new Decryptor(EncryptionAlgorithm.TripleDes);

dec.IV = Encoding.ASCII.GetBytes(ssIV);
byte[] key = Encoding.ASCII.GetBytes(ssKEY);

byte[] plainText = dec.Decrypt(Convert.FromBase64String(encryptedCCNumber), key);
return Encoding.ASCII.GetString(plainText);

The issue is that the key is 16 characters, and that is an illegal length for the java decryption. Am I using the wrong algorithm on the java side?

Yann, I haven't experienced this problem befor...

2009-08-14T08:19:08.179-07:00

Yann, I haven't experienced this problem before, but I'll take a look. In the mean time, if you end up figuring out the solution, make sure you post it. Thanks!

Sam

Sorry, in fact it's not due to to the "/&...

2009-08-14T06:17:05.572-07:00

Sorry, in fact it's not due to to the "/"

I tried to encrypt this random string "AeRTYhgFD678de4" with these key "4d89g13j4j91j27c582ji693" and iv "zerocool".

In Java i got : cANU9X90FvhHP5wH3t9VMQ==

In C# I got:cANU9X90FvhHgZwH3t9VMQ==

So I can't decrypt the encrypted text from java.

Hi Sam, I've tried your code and it seems to w...

2009-08-14T05:24:37.482-07:00

Hi Sam, I've tried your code and it seems to work excepted when you get an encryted text from java wi th at least one "/" . The C# method can't decrypt the message.Have you already face to this problem ?

From first glance, it looks like an encoding issue...

2009-08-04T09:28:40.300-07:00

From first glance, it looks like an encoding issue, but I'd have to see your code to make a better guess.

Hey great info, I am also dealing with this proble...

2009-08-04T09:05:28.594-07:00

Hey great info, I am also dealing with this problem, but I am doing it from C# Desktop application to a Java servlet, so I need to decrypt on the Java side, I tried to replicate the C# code for decrypt in Java but I only get a 40% of the message decrypted fine, any idea?

For example I sent this as the text to encrypt "_2G4WS52M6W1459365" and I get this "_2G4WS52J��iS�5_2G4WS52J��iS�5"