Question

I have this vb.net code ( but I think meaning code is equivalent for c# too) that I have to replicate in Java and I can’t modify it in anyway (just replicate):

Public Shared Function Encrypt(ByVal plainText As String, Optional key As String = "") As String

    If String.IsNullOrEmpty(key) Then key = "sfdjf48mdfdf3054"

    Dim encrypted As String = Nothing
    Try

        Dim inputBytes As Byte() = ASCIIEncoding.ASCII.GetBytes(plainText)
        Dim pwdhash As Byte() = Nothing

        'generate an MD5 hash from the password.
        'a hash is a one way encryption meaning once you generate
        'the hash, you cant derive the password back from it.
        Dim hashmd5 As New MD5CryptoServiceProvider()
        pwdhash = hashmd5.ComputeHash(ASCIIEncoding.ASCII.GetBytes(key))
        hashmd5 = Nothing

        ' Create a new TripleDES service provider
        Dim tdesProvider As New TripleDESCryptoServiceProvider()
        tdesProvider.Key = pwdhash
        tdesProvider.Mode = CipherMode.ECB

        encrypted = Convert.ToBase64String(tdesProvider.CreateEncryptor().TransformFinalBlock(inputBytes, 0, inputBytes.Length))

    Catch e As Exception
        Dim str As String = e.Message
        Throw
    End Try
    Return encrypted
End Function

Exactly, this is a .NET Utility Class function.

Now,

I don’t know how to replicate

TripleDESCryptoServiceProvider()

In java code I began to write some code, but I don’t know how to continue:

public static String encrypt(String plaintext, String enctoken){

    if(enctoken == null)
        enctoken = "sfdjf48mdfdf3054";

    String encrypted = null;

    byte[] plaintextByte = EncodingUtils.getAsciiBytes(plaintext);

    //nel caso non funzionasse provare getBytes semplicemente
    byte[] pwd = EncodingUtils.getAsciiBytes(Connessione.md5(enctoken));        

    try {
        Cipher cipher = Cipher.getInstance("DESEDE/ECB/NoPadding");
        SecretKeySpec myKey = new SecretKeySpec(pwd,"DESede");

        cipher.init( Cipher.ENCRYPT_MODE, myKey);

        try {
            byte[] encryptedPlainText= cipher.doFinal(plaintextByte);

            encrypted = Base64.encodeToString(encryptedPlainText, 0); 
            return encrypted;

        } catch (IllegalBlockSizeException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (BadPaddingException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    } catch (NoSuchAlgorithmException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (NoSuchPaddingException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (InvalidKeyException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }       

    return "";
}

UPDATE:

I’ve just updated code. Now should be good. Enctoken String will be a string data rappresentation (just known). In this way, only if second parameter is NULL then fixed key is setted

UPDATE 2

Unfortunally c# hash is always different from Java hash!!
How to replicate this in java ??

 Dim hashmd5 As New MD5CryptoServiceProvider()
    pwdhash = hashmd5.ComputeHash(ASCIIEncoding.ASCII.GetBytes(key))
    hashmd5 = Nothing

    ' Create a new TripleDES service provider
    Dim tdesProvider As New TripleDESCryptoServiceProvider()
    tdesProvider.Key = pwdhash
    tdesProvider.Mode = CipherMode.ECB

    encrypted = Convert.ToBase64String(tdesProvider.CreateEncryptor().TransformFinalBlock(inputBytes, 0, inputBytes.Length))

I tried in this way but it doesn’t work:

HASH

public static final String md5(byte[] s) { 
    try { 

        MessageDigest m = MessageDigest.getInstance("MD5");
        byte[] digest = m.digest(s);
        String hash = EncodingUtils.getAsciiString(digest, 0, 16);
        Log.i("MD5", "Hash: "+hash);

        return hash;

    } catch (NoSuchAlgorithmException e) {
    e.printStackTrace();
    }
    return "";
}   

Answer 1

Fixed by myself! Following function gives same MD5 HASH result:

JAVA HASH MD5

public static final byte[] md5(String s) { 
    try { 

        MessageDigest md = MessageDigest.getInstance("MD5");
        byte[] messageDigest = md.digest(s.getBytes("UTF-8"));

        String md5 = EncodingUtils.getString(messageDigest, "UTF-8");

        Log.i("Function MD5", md5);
        Log.i("Function MD5 Length","Length: "+ md5.length());

        return messageDigest;

    } catch (NoSuchAlgorithmException e) {
        e.printStackTrace();
    } catch (UnsupportedEncodingException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } 
    return null;
}   

VB.NET HASH MD5

Dim hashmd5 As New MD5CryptoServiceProvider()
pwdhash = hashmd5.ComputeHash(ASCIIEncoding.ASCII.GetBytes(key))

And, TRIPLE-DES ECB JAVA is

try {
        Cipher cipher = Cipher.getInstance("DESEDE/ECB/PKCS5Padding");
        SecretKeySpec myKey = new SecretKeySpec(hash,"DESede");

        cipher.init(Cipher.ENCRYPT_MODE, myKey);

        try {
            byte[] encryptedPlainText = cipher.doFinal(plaintextByte);

            encrypted = Base64.encodeToString(encryptedPlainText, 0); 
            Log.i("ENCRYPT", "Pwd encrypted: "+encrypted);
            return encrypted;

        } catch (IllegalBlockSizeException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (BadPaddingException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    } catch (NoSuchAlgorithmException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (NoSuchPaddingException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (InvalidKeyException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }       

TRIPLE-DES VB.NET is

' Create a new TripleDES service provider
    Dim tdesProvider As New TripleDESCryptoServiceProvider()
    tdesProvider.Key = pwdhash
    tdesProvider.Mode = CipherMode.ECB

    encrypted = Convert.ToBase64String(tdesProvider.CreateEncryptor().TransformFinalBlock(inputBytes, 0, inputBytes.Length))