public IntermediateRound(Settings settings, KeySchedule keySchedule)
: base(new SubBytes(settings),
new ShiftRows(settings),
new MixColumns(settings),
new AddRoundKey(settings, keySchedule))
{
}
public FinalRound(Settings settings, KeySchedule keySchedule)
: base(
new SubBytes(settings),
new ShiftRows(settings),
new AddRoundKey(settings, keySchedule)
)
{
}
private void ShuffleWordTransforms()
{
int count = transforms.Length;
byte[] random = new byte[count];
KeySchedule.GetNext(count * 8).CopyTo(random, 0);
for (int i = 0; i < count; i++)
{
int r = random[i] % count;
transforms.Swap(i, r);
}
}
private void InstantiateWordTransforms()
{
int count = PossibleTransforms.Length;
transforms = new IWordEncoder[count];
for (int i = 0; i < count; i++)
{
IWordEncoder transform = (IWordEncoder)Activator.CreateInstance(PossibleTransforms[i]);
transform.WordSize = wordSize;
if (transform.SeedSize != 0)
{
transform.Seed = KeySchedule.GetNext(transform.SeedSize);
}
transforms[i] = transform;
}
}
public EncodingPlan GetEncodingPlan(int blockLength)
{
EncodingPlan result = new EncodingPlan();
result.WordSize = wordSize;
int transformsCount = Transforms.Length;
int bitsInBlock = blockLength * 8;
int remainder = bitsInBlock % wordSize;
bool hasRemainder = remainder != 0;
int wordCount = (int)Math.Ceiling((double)bitsInBlock / wordSize);
for (int index = 0; index < wordCount; index++)
{
int wordLength = (index == wordCount - 1 && hasRemainder ? remainder : wordSize);
IWordEncoder encoder = (IWordEncoder)Activator.CreateInstance(transforms[index % transformsCount].GetType());
encoder.WordSize = wordLength;
encoder.Seed = KeySchedule.GetNext(encoder.SeedSize);
result.Transformations.Add(encoder);
}
return(result);
}
public InitialRound(Settings settings, KeySchedule keySchedule)
: base(new AddRoundKey(settings, keySchedule))
{
}
private void NewWordSize()
{
byte[] random = new byte[1];
KeySchedule.GetNext(8).CopyTo(random, 0);
wordSize = (MinWordSize + random[0] % (MaxWordSize - MinWordSize + 1));
}
public AddRoundKey(Settings settings, KeySchedule keySchedule)
: base(settings)
{
_KeySchedule = keySchedule;
}