/// <summary>
/// Convert your data to multipass token and get redirect url for shopify mutipass
/// </summary>
/// <param name="data"></param>
/// <returns></returns>
public string GetMultipassRedirectUrl(ShopifyProfile data)
{
var token = GetMultipassToken(data);
//build redirect url
return(string.Format("https://{0}/account/login/multipass/{1}", _shopifyShopDomain, token));
}
public string GetMultipassToken(ShopifyProfile profile)
{
//Generate encryption key and signature key by SHA 256
var keys = new MessageDigestContext(MessageDigest.SHA256).Digest(Encoding.UTF8.GetBytes(_shopifyMultipassSecret));
//First 16 bytes will be encryption key and last 16 bytes will be signature key
ArraySegment <byte> encryptionKeyArraySegmenet = new ArraySegment <byte>(keys, 0, 16);
ArraySegment <byte> signatureKeyArraySegmenet = new ArraySegment <byte>(keys, 16, 16);
var encryptionKey = encryptionKeyArraySegmenet.ToArray();
var signatureKey = signatureKeyArraySegmenet.ToArray();
var dataString = JsonConvert.SerializeObject(profile);
var dataBytes = Encoding.UTF8.GetBytes(dataString);
//generate random 16 bytes for Init Vactor
var iv = new byte[16];
new RNGCryptoServiceProvider().GetBytes(iv);
//Generate Cipher using AES-128-CBC algo and concat Init Vector with this.
var cipher = Combine(iv, new CipherContext(Cipher.AES_128_CBC).Crypt(dataBytes, encryptionKey, iv, true));
//Generate signature of Cipher
HMACSHA256 hasher = new HMACSHA256(signatureKey);
byte[] sing = hasher.ComputeHash(cipher);
//append signature to cipher and convert it to URL safe base64 string
var token = Convert.ToBase64String(Combine(cipher, sing)).Replace("+", "-").Replace("/", "_");
return(token);
}