internal static void ThrowOnBadKey(BitArray key, KeySize keysize)
{
if (key.Length % keysize.ConvertToInt() != 0)
{
throw new MismatchedKeySizeException();
}
}
internal static List <BitArray> ExpandKey(BitArray key, KeySize keySize)
{
int rounds = keySize.NumRounds();
int length = keySize.ConvertToInt();
var keys = new BitArray(rounds * length);
var prev = key;
for (int i = 0; i < rounds; i++)
{
var next = prev.Next(i + 1);
next.CopyTo(keys, length * i);
}
return(keys.SeparateBlocks());
}