public bool VerifyOtp(string code, byte[] challenge = null, int forward = 1, int back = 1)
{
if (string.IsNullOrEmpty(code) || code.Length != CodeLength || (CachingProvider != null && !CachingProvider.ValidateToken(code)))
{
return(false);
}
long State = GetState(-back);
List <string> Tried = new List <string>();
for (int I = 0; I <= (forward + back); I++)
{
string Code = GetOtp(state: State + I, challenge: challenge);
Tried.Add(code);
if (Code == code)
{
if (CachingProvider != null)
{
CachingProvider.CancelTokens(Type, Tried);
}
if (Type == OtpType.HOTP)
{
HotpCounter = State + I + 1;
}
return(true);
}
}
return(false);
}