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I've got this C# code to encrypt/decrypt strings:

private static byte[] EncryptString(byte[] clearText, byte[] Key, byte[] IV)
{
    MemoryStream ms = new MemoryStream();
    Rijndael alg = Rijndael.Create();
    alg.Key = Key;
    alg.IV = IV;
    CryptoStream cs = new CryptoStream(ms, alg.CreateEncryptor(), CryptoStreamMode.Write);
    cs.Write(clearText, 0, clearText.Length);
    cs.Close();
    byte[] encryptedData = ms.ToArray();
    return encryptedData;
}

public static string EncryptString(string clearText, string Password)
{
    byte[] clearBytes = System.Text.Encoding.Unicode.GetBytes(clearText);
    PasswordDeriveBytes pdb = new PasswordDeriveBytes(Password, new byte[] { 0x74, 0x68, 0x69, 0x73, 0x69, 0x61, 0x74, 0x65, 0x73, 0x74 });
    byte[] encryptedData = EncryptString(clearBytes, pdb.GetBytes(32), pdb.GetBytes(16));
    return Convert.ToBase64String(encryptedData);
}

private static byte[] DecryptString(byte[] cipherData, byte[] Key, byte[] IV)
{
    MemoryStream ms = new MemoryStream();
    Rijndael alg = Rijndael.Create();
    alg.Key = Key;
    alg.IV = IV;
    CryptoStream cs = new CryptoStream(ms, alg.CreateDecryptor(), CryptoStreamMode.Write);
    cs.Write(cipherData, 0, cipherData.Length);
    cs.Close();
    byte[] decryptedData = ms.ToArray();
    return decryptedData;
}

public static string DecryptString(string cipherText, string Password)
{
    if (!string.IsNullOrEmpty(cipherText))
    {
        byte[] cipherBytes = Convert.FromBase64String(cipherText);
        PasswordDeriveBytes pdb = new PasswordDeriveBytes(Password, new byte[] { 0x74, 0x68, 0x69, 0x73, 0x69, 0x61, 0x74, 0x65, 0x73, 0x74 });
        byte[] decryptedData = DecryptString(cipherBytes, pdb.GetBytes(32), pdb.GetBytes(16));
        return System.Text.Encoding.Unicode.GetString(decryptedData);
    }
    else
    {
        return "";
    }
}

Encrypted strings should be stored locally in the registry or a file. A Delphi application has to have access to this strings too. Please note that, for some reason, it is not possible to outsource the encryption/decryption code to a DLL.

My Problem is that i am not able to produce "PasswordDerivedBytes" in Delphi. Can somebody please give me a hint how that can work?

Action Heinz
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    Unfortunately, StackOverflow isn't here to convert your code from language to language. You need to do your own research and do this yourself, and when you have a specific issue, ask about that specific issue. – Jerry Dodge Sep 22 '13 at 15:26
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    There are plenty of Rijndael implementations. Find one and use it. – David Heffernan Sep 22 '13 at 16:27
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    I'm sorry for asking my question in an improper way. Yes you are right, you can have the impression that i want a conversation of my code from C# to Delphi but that was not my intention. Please let me clarify my question: my special problem is that i'm not able to get the counterpart of "PasswordDerivedBytes" in Delphi. Therefore i'm not able to get the right result in Delphi. Can you give me a hint how to build PasswordDerivedBytes in Delphi? – Action Heinz Sep 22 '13 at 17:48
  • Please put the details in the question and not comments. Edit the question. – David Heffernan Sep 22 '13 at 18:30
  • `PasswordDerivedBytes` must be a type which is proprietary to the code you posted, but your code doesn't include this. Are you sure this is all the code? – Jerry Dodge Sep 22 '13 at 21:25
  • A Google search nets [this](http://msdn.microsoft.com/en-us/library/system.security.cryptography.passwordderivebytes.aspx) and the call is also documented [here](http://stackoverflow.com/questions/9231754/c-sharp-passwordderivebytes-confusion) for what it's worth. This is probably the code that is being called. It should be noted that the call is deprecated and [Rfc2898DeriveBytes](http://msdn.microsoft.com/en-us/library/system.security.cryptography.rfc2898derivebytes.aspx) seems to be favored. – Glenn1234 Sep 23 '13 at 03:28
  • Though, if you are trying to duplicate this in straight Delphi as opposed to .NET, try something like [this](http://stackoverflow.com/questions/14411975/simple-code-to-encrypt-an-ini-file-string-using-a-password/14462455#14462455) instead of trying to reinvent the wheel. – Glenn1234 Sep 23 '13 at 03:29
  • Check this [SO reply](http://stackoverflow.com/a/18016448/197962) for a (fairly rough) PHP implementation of PBKDF1 / PasswordDeriveBytes that works against MS / C# encryption. I know it's not Delphi but I don't think it's rocket science to translate it. – shunty Sep 23 '13 at 08:33

1 Answers1

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I would suggest to you to use the Delphi Encryption Compedium. It has almost anything you need cryptowise and hase some examples which mostly do what you want to do.

Tim Schumacher
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