public FormsAuthenticationTicket Decrypt(string formsAuthCredential)
{
var derivedEncryptionKey = _purpose.GetDerivedEncryptionKey(_masterKeyProvider, SP800_108.DeriveKey);
var derivedValidationKey = _purpose.GetDerivedValidationKey(_masterKeyProvider, SP800_108.DeriveKey);
var cryptoService = new NetFXCryptoService(_cryptoAlgorithmFactory, derivedEncryptionKey, derivedValidationKey);
SerializedTicket = cryptoService.Unprotect(CryptoUtil.HexToBinary(formsAuthCredential));
return(FormsAuthenticationTicketSerializer.Deserialize(SerializedTicket, SerializedTicket.Length));
}