/// <summary>
/// Initializes with a hexadecimal DES key.
/// </summary>
/// <param name="text">Hexadecimal representation of the DES key.</param>
private void Init(string text)
{
Guard.IsTrue(text.IsHex(), "Key is not hexadecimal.");
Guard.IsOneOfSupplied <int>(text.Length, new List <int>()
{
16, 32, 48
}, "Key must be 16, 32 or 48 hexadecimal characters");
text = text.ToUpper();
switch (text.Length)
{
case 16:
_keyA = text;
_keyB = _keyA;
_keyC = _keyA;
_keyType = DesKeyType.SingleLength;
break;
case 32:
_keyA = text.Substring(0, 16);
_keyB = text.Substring(16, 16);
_keyC = _keyA;
_keyType = DesKeyType.DoubleLength;
break;
default:
_keyA = text.Substring(0, 16);
_keyB = text.Substring(16, 16);
_keyC = text.Substring(32, 16);
_keyType = DesKeyType.TripleLength;
break;
}
}
/// <summary>
/// Creates a new random DES key.
/// </summary>
/// <param name="type">The DES key type (single, double or triple length).</param>
public DESKey(DesKeyType type)
{
switch (type)
{
case DesKeyType.SingleLength:
Init(GetRandomHex());
break;
case DesKeyType.DoubleLength:
Init(GetRandomHex() + GetRandomHex());
break;
default:
Init(GetRandomHex() + GetRandomHex() + GetRandomHex());
break;
}
}
