Ruby sha and hash to c#

Question

Im trying to translate this to c#

f1 = Digest::SHA1.hexdigest(@password)
f2 = nonce + ":" + f1
Digest::MD5.hexdigest(f2)    

My Code

private static string GetSHA1HashData(string data)
{
    //create new instance of md5
    SHA1 sha1 = SHA1.Create();

    //convert the input text to array of bytes
    byte[] hashData = sha1.ComputeHash(Encoding.Default.GetBytes(data));

    //create new instance of StringBuilder to save hashed data
    StringBuilder returnValue = new StringBuilder();
    //loop for each byte and add it to StringBuilder
    for (int i = 0; i < hashData.Length; i++)
    {
        returnValue.Append(hashData[i].ToString());
    }

    // return hexadecimal string
    return returnValue.ToString();
}
public static string CreateMD5Hash(string input)
{
    // Use input string to calculate MD5 hash
    MD5 md5 = System.Security.Cryptography.MD5.Create();
    byte[] inputBytes = System.Text.Encoding.ASCII.GetBytes(input);
    byte[] hashBytes = md5.ComputeHash(inputBytes);

    // Convert the byte array to hexadecimal string
    StringBuilder sb = new StringBuilder();
    for (int i = 0; i < hashBytes.Length; i++)
    {
        sb.Append(hashBytes[i].ToString("X2"));
        // To force the hex string to lower-case letters instead of
        // upper-case, use he following line instead:
        // sb.Append(hashBytes[i].ToString("x2")); 
    }
    return sb.ToString();
}

Call

var nonce = "1386755695841";
var password = "edc123";
var sha = GetSHA1HashData(password);
var md5 = CreateMD5Hash(nonce + ":" + sha);

But i cant get it right, any ideas

Answer 1

The problem is that .NET uses UTF-16 by default whilst Ruby will use something else (normally UTF-8, but it may also respect encoding that has been set by database or web source).

I think you just need to alter one line:

//convert the input text to array of bytes
byte[] hashData = sha1.ComputeHash(Encoding.ASCII.GetBytes(data));

You may need UTF-8 or even some other encoding instead, depending on the range of passwords accepted by the Ruby version. However, the ASCII coding should at least prove correctness of this answer in general from your sample data.