使用SHA256的PayFort签名

Question

https://docs.payfort.com/docs/in-common/build/index.html#create-signature-value

I need some assistance regarding generating SHA256 Signature for PayFort Tokenization. The example in the link gives you basic guideline on how to tokenize your request, but what I need is information on how to generate SHA256 Signature with a secret key and decrypt the response signature with a key. I have all the data required for request and response paraphrase keys. I don't exactly understand how to generate proper SHA256 Signature with a secret key in C#. I tried different examples to generate SHA256 signature, but it returns signature mismatch.

The example from PayFort's Documentation:

SHA Request Phrase: PASS 
SHA-Type: SHA-256

PASSaccess_code=SILgpo7pWbmzuURp2qrilanguage=enmerchant_identifier=MxvOupuGmerchant_reference=MyReference0001service_command=TOKENIZATIONPASS

How can I properly encrypt and decrypt it in C#.

Any help is appreciated.

Edit:

I am firing in the blind, Anybody familiar with PayFort Integration with C# can guide me

public static String Sign(String data, String key)
{
    KeyedHashAlgorithm algorithm = new HMACSHA256();
    Encoding encoding = new UTF8Encoding();
    algorithm.Key = encoding.GetBytes(key);
    return Convert.ToBase64String(algorithm.ComputeHash(
        encoding.GetBytes(data.ToCharArray())));
}

Answer 1

Firstly you need to generate your signature as a string. Signature includes accesscode, language etc. Then convert that signature to bytes. Then initialize a sha256Managed object. Pass the bytes paramter to that object and this will return you another byte but with sha256Managed format. Now you need to set its format in foreach.

Please find the below code this will help you out.

byte[] bytes = Encoding.UTF8.GetBytes(signature);
            SHA256Managed hashstring = new SHA256Managed();
            byte[] hash = hashstring.ComputeHash(bytes);
            string hashString = string.Empty;
            foreach (byte x in hash)
            {
                hashString += String.Format("{0:x2}", x);
            }