private byte[] Process(BitBlock[] subKeys, byte[] next8ByteBlock)
{
BitBlock next64BitBlock = new BitBlock(next8ByteBlock);
BitBlock initialPermutation_Output = InitialPermutation(next64BitBlock);
BitBlock leftSide = initialPermutation_Output.LeftSide();
BitBlock rightSide = initialPermutation_Output.RightSide();
// 16 Rounds of Encryption/Decryption
for (int i = 0; i <= 15; i++)
{
BitBlock F_Output = F(rightSide, subKeys[i]);
BitBlock tempRightSide = leftSide ^ F_Output;
leftSide = rightSide;
rightSide = tempRightSide;
}
BitBlock finalPermutation_Output = FinalPermutation(rightSide + leftSide);
byte[] byteArray = BitBlock.ConvertToByteArray(finalPermutation_Output);
return(byteArray);
}
private BitBlock[] GenerateSubKeys(ProcessType process, BitBlock masterKey)
{
BitBlock PC1_Output = PC1(masterKey);
BitBlock cBlock = PC1_Output.LeftSide();
BitBlock dBlock = PC1_Output.RightSide();
BitBlock[] subKeys = new BitBlock[16];
switch (process)
{
case ProcessType.Encrypt:
#region Encrypt
for (int round = 1; round <= 16; round++)
{
if (round == 1 || round == 2 || round == 9 || round == 16)
{
cBlock = cBlock << 1;
dBlock = dBlock << 1;
}
else
{
cBlock = cBlock << 2;
dBlock = dBlock << 2;
}
BitBlock key = PC2(cBlock + dBlock);
subKeys[round - 1] = key;
}
break;
#endregion
case ProcessType.Decrypt:
#region Decrypt
for (int round = 1; round <= 16; round++)
{
if (round == 1)
{
// No Rotation
}
else if (round == 2 || round == 9 || round == 16)
{
cBlock = cBlock >> 1;
dBlock = dBlock >> 1;
}
else
{
cBlock = cBlock >> 2;
dBlock = dBlock >> 2;
}
BitBlock key = PC2(cBlock + dBlock);
subKeys[round - 1] = key;
}
break;
#endregion
}
return(subKeys);
}