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DES Encryption in Java vs. .NET - Why Another?

I have a .NET method for DES encryption in a line:

public static string EncryptTripleDES(string value, byte[] encryptionKey, byte[] initializationVector) {
  if (!value.IsNullOrEmpty()) {
    TripleDESCryptoServiceProvider cryptoProvider = new TripleDESCryptoServiceProvider();
    MemoryStream ms = new MemoryStream();
    CryptoStream cs = new CryptoStream(ms, cryptoProvider.CreateEncryptor(encryptionKey, initializationVector), CryptoStreamMode.Write);
    StreamWriter sw = new StreamWriter(cs);
    sw.Write(value);
    sw.Flush();
    cs.FlushFinalBlock();
    ms.Flush();
    //convert back to a string
    return Convert.ToBase64String(ms.GetBuffer(), 0, (int)ms.Length);
  } else {
    return "";
  }
}

As you can see, the algorithm accepts 2 parameters - “encryption key” and “initialization vector”.

Now I need to write a DES encryption / decryption function in Java parallel to this function, so if you provide the same encryption key and initialization vector, you can decrypt something encrypted in C # in Java. (Imposes overalls on Java, discards about 10 years since the last use of Java, Googles for DES encryption in Java ...)

A decent Java DES encryption approach is found here . But oh, honey, it turns out that this algorithm insists on an initialization vector of exactly 8 bytes; the .NET code uses an init vector of 24 bytes!

? Java 8- ? , 24- ?

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8 24- Java? , , , 8 , Triple DES 8 . , .NET- , , , IV . , . , 8- IV.

.NET , . , .NET , , CBC. , , , CBC PKCS5Padding . , , .

Java, , #, 24- IV, 8- IV, Java, . , - . Bouncycastle, @Tim, , , ,.NET .

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MSDN:

IV , GenerateIV. IV , BlockSize.

, , BlockSize, IV .

, , , DES 8 (64 , 8 , 56 ). TripleDES (3DES) 24 ( 192 , 24 , 168 ).

, TripleDES Java ( , , SO Question), , DES .NET.

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Have you looked at the Bouncy Castle library for Java? I cannot tell from their (very rare) documentation and samples, but it seems to be a widely used library, so I hope it will be so flexible. It’s worth a look, at least if you haven’t done it yet.

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