我如何知道我使用的是Triple Des Algorithm实现的正确版本？

Question

I searched over the internet for a Triple Des Algorithm implementation for Java.

I found a lot of solutions and choosed one (The one with better documentation for me). I tested and works Ok.

Then, I searched for an AES Algorithm implementation for Java. And found a good ones. Really similar to Triple Des Algorithm implementation, but not exactly the same.

So I think, what appends if I use the AES Algorithm implementation but changing the Cipher instance parameter from "AES" to "DESede"? I made the change, tested the code and worked ok. But, the String returned it is different from the String returned on my previous Triple Des Algorithm implementation.

So, like the title say, how do I know if I'm using the right version of Triple Des Algorithm implementation?

This is the first implementation:

public String encrypt(SecretKey key, String stringIn){

    String outString = "";      

    if (stringIn.isEmpty() || stringIn.toUpperCase().equals("NULL")){
        return "";
    }

    try {   

        if (key == null)
            key = this.key;


        InputStream in = new ByteArrayInputStream(stringIn.getBytes("UTF-8"));

        ByteArrayOutputStream out = new ByteArrayOutputStream();

        // Create and initialize the encryption engine
        Cipher cipher = Cipher.getInstance("DESede");
        cipher.init(Cipher.ENCRYPT_MODE, key);

        // Create a special output stream to do the work for us
        CipherOutputStream cos = new CipherOutputStream(out, cipher);

        // Read from the input and write to the encrypting output stream
        byte[] buffer = new byte[2048];

        int bytesRead;

        while ((bytesRead = in.read(buffer)) != -1) {
            cos.write(buffer, 0, bytesRead);
        }

        cos.close();

        // For extra security, don't leave any plaintext hanging around memory.
        java.util.Arrays.fill(buffer, (byte) 0);

        outString = out.toString();

    } catch (UnsupportedEncodingException e) {

        e.printStackTrace();

    } catch (NoSuchAlgorithmException e) {

        e.printStackTrace();

    } catch (NoSuchPaddingException e) {

        e.printStackTrace();

    } catch (InvalidKeyException e) {

        e.printStackTrace();

    } catch (IOException e) {

        e.printStackTrace();

    } finally {

        return outString;
    }

}

This is the second one:

public String encrypt(SecretKey key, String stringIn){

    String outString = "";      

    if (stringIn.isEmpty() || stringIn.toUpperCase().equals("NULL")){
        return "";
    }


    try {   

        if (key == null)
            key = this.key;

        Cipher ecipher = Cipher.getInstance("DESede");

        ecipher.init(Cipher.ENCRYPT_MODE, key);

        byte[] bytes = stringIn.getBytes("UTF8");

        byte[] encVal = ecipher.doFinal(bytes);

        outString = new sun.misc.BASE64Encoder().encode(encVal);

    } catch (UnsupportedEncodingException e) {

        e.printStackTrace();

    } catch (NoSuchAlgorithmException e) {

        e.printStackTrace();

    } catch (NoSuchPaddingException e) {

        e.printStackTrace();

    } catch (InvalidKeyException e) {

        e.printStackTrace();

    } catch (IOException e) {

        e.printStackTrace();

    } finally {

        return outString;
    }

}

This is the Test case:

    String In: 6985475896580019
    String Returned when I Encripted with First code: Kœ¼i …€‡ä«‘]<žéù âpU
    String Returned when I Encripted with Second code: w1ujopasjH6ccFKgUtOgansFNBtxbWe8YwDhso2pZN8=

Sorry for my poor english.

Thanks for your help

Answer 1

cipher.init(mode,key) generates a random IV. This is actually the most secure way of using it; you should use .getIV() and return that with the encrypted text (which is also automatic; Java tacks it onto the first few bytes of the cryptostream, which is how they decrypt OK). Different IV changes the result just as much as a different key, but it doesn't need to be secret, it's just to make sure identical things don't encrypt identically.

To force an IV for comparing algorithms, or for decrypting with a known one not included, use cipher.init(mode,key,new IvParameterSpec(iv))