public async Task <TotpResult> ValidateAccountTOTPAsync(string globalId, string code, Func <string, string, Task <bool> > dupeChecker = null)
{
var result = new TotpResult
{
Code = code,
Timestamp = DateTime.UtcNow
};
if (!Int32.TryParse(code, out int number))
{
return(result);
}
var account = await _store.LoadByGuid(globalId);
if (account != null)
{
var token = account.Tokens.Where(t => t.Type == AccountTokenType.TOTP).FirstOrDefault();
if (token != null)
{
var otp = new OtpNet.Totp(Encoding.UTF8.GetBytes(token.Hash)); //, mode: OtpHashMode.Sha256);
if (otp.VerifyTotp(code, out long matchedStep, new OtpNet.VerificationWindow(1, 1)))
{
result.Valid = (dupeChecker != null)
? await dupeChecker.Invoke(globalId, matchedStep.ToString())
: true;
}
}
}
return(result);
}
/// <summary>
/// Pass in a valid Base-32 encoded TOTP-Secret; receive a valid 2FA token.<para> </para>
/// If the token would be closer than 2 seconds to expiry, the method waits for a fresh one to avoid authentication failures due to latency.
/// </summary>
/// <param name="totpSecret">The Base-32 encoded secret to use for TOTP generation. If this is <c>null</c> or empty, <c>null</c> is returned.</param>
/// <returns>The 6-cipher string containing the TOTP; <c>null</c> if generation failed for some reason (e.g. invalid <paramref name="totpSecret"/> parameter).</returns>
public async Task <string> GetTotp(string totpSecret)
{
if (totpSecret.NullOrEmpty())
{
return(null);
}
try
{
var totp = new OtpNet.Totp(Base32Encoding.ToBytes(totpSecret));
if (totp.RemainingSeconds() < 2)
{
await Task.Delay(1250);
}
return(totp.ComputeTotp());
}
catch (Exception)
{
return(null);
}
}
public Totp(string secret, int period, OtpHashMode algorithm, int digits)
{
var secretBytes = Base32Encoding.ToBytes(secret);
_totp = new OtpNet.Totp(secretBytes, period, algorithm, digits);
}
public SteamOtp(string secret)
{
var secretBytes = Base32Encoding.ToBytes(secret);
_totp = new SteamTotp(secretBytes);
}