/// <remarks> /// This method mainly exists for unit tests. /// The RFC defines a decimal value in the test table that is an /// intermediate step to a final HOTP value /// </remarks> internal long ComputeHotpDecimal(long counter, OtpHashMode mode) => CalculateOtp(KeyUtilities.GetBigEndianBytes(counter), mode);
/// <summary> /// Takes a time step and computes a TOTP code /// </summary> /// <param name="counter">time step</param> /// <param name="mode">The hash mode to use</param> /// <returns>TOTP calculated code</returns> protected override string Compute(long counter, OtpHashMode mode) => Digits(CalculateOtp(KeyUtilities.GetBigEndianBytes(counter), mode), _totpSize);
/// <summary> /// Uses the procedure defined in RFC 4226 section 7.5 to derive a key from the master key /// </summary> /// <param name="masterKey">The master key from which to derive a device specific key</param> /// <param name="serialNumber">A serial number that is unique to the authenticating device</param> /// <param name="mode">The hash mode to use. This will determine the resulting key lenght. The default is sha-1 (as per the RFC) which is 20 bytes</param> /// <returns>Derived key</returns> public static byte[] DeriveKeyFromMaster(IKeyProvider masterKey, int serialNumber, OtpHashMode mode = OtpHashMode.Sha1) => DeriveKeyFromMaster(masterKey, KeyUtilities.GetBigEndianBytes(serialNumber), mode);
