/// <summary>
/// Generate a Totp using provided binary data.
/// </summary>
/// <param name="key">Binary data.</param>
/// <returns>Time-based One Time Password.</returns>
public string Generate(byte[] key)
{
System.Security.Cryptography.HMACSHA1 hmac = new System.Security.Cryptography.HMACSHA1(key, true); //Instanciates a new hash provider with a key.
byte[] hash = hmac.ComputeHash(GetBytes((ulong)Counter)); //Generates hash from key using counter.
hmac.Clear(); //Clear hash instance securing the key.
int offset = hash[hash.Length - 1] & 0xf; //Math.
int binary = //Math.
((hash[offset] & 0x7f) << 24) //Math.
| ((hash[offset + 1] & 0xff) << 16) //Math.
| ((hash[offset + 2] & 0xff) << 8) //Math.
| (hash[offset + 3] & 0xff); //Math.
int password = binary % (int)Math.Pow(10, _Length); //Math.
return(password.ToString(new string('0', _Length))); //Math.
}
/// <summary>
/// Generate a Totp using provided binary data.
/// </summary>
/// <param name="key">Binary data.</param>
/// <returns>Time-based One Time Password.</returns>
public string Generate(byte[] key)
{
System.Security.Cryptography.HMACSHA1 hmac = new System.Security.Cryptography.HMACSHA1(key, true); //Instanciates a new hash provider with a key.
byte[] hash = hmac.ComputeHash(GetBytes((ulong)Counter)); //Generates hash from key using counter.
hmac.Clear(); //Clear hash instance securing the key.
int offset = hash[hash.Length - 1] & 0xf; //Math.
int binary = //Math.
((hash[offset] & 0x7f) << 24) //Math.
| ((hash[offset + 1] & 0xff) << 16) //Math.
| ((hash[offset + 2] & 0xff) << 8) //Math.
| (hash[offset + 3] & 0xff); //Math.
int password = binary % (int)Math.Pow(10, _Length); //Math.
return password.ToString(new string('0', _Length)); //Math.
}