private void WriteBlock(uint[] K)
{
_byteWriter.WriteBytes(Word32Bits.ToBytes(K[2]));
_byteWriter.WriteBytes(Word32Bits.ToBytes(K[3]));
_byteWriter.WriteBytes(Word32Bits.ToBytes(K[0]));
_byteWriter.WriteBytes(Word32Bits.ToBytes(K[1]));
}
public void WriteWords(uint[] words)
{
foreach (var word in words)
{
WriteBytes(Word32Bits.ToBytes(word));
}
}
private void ReadWords(byte[] key, uint[] words)
{
for (int i = 0; i < key.Length / 4; i++)
{
words[i] = Word32Bits.ToUint(key.SubArray(i * 4, i * 4 + 4));
}
}
public void ToUint_ConvertsToUint_Converted()
{
byte[] bytes = { 2, 108, 209, 77 };
uint excepted = 1305570306;
Assert.AreEqual(excepted, Word32Bits.ToUint(bytes));
}
public void RotateRight_RotatesTwoBits_Rotated()
{
uint value = 6;
uint expected = 2147483649;
Assert.AreEqual(expected, Word32Bits.RotateRight(value, 2));
}
public void ToBytes_ConvertsToBytesLittleEndian_Converted()
{
uint word = 40685901;
byte[] excepted = { 2, 108, 209, 77 };
CollectionAssert.AreEqual(excepted, Word32Bits.ToBytes(word, ValueRepresentation.LittleEndian));
}
public void RotateRight_RotatesOneBit_Rotated()
{
uint value = 3;
uint expected = 2147483649;
Assert.AreEqual(expected, Word32Bits.RotateRight(value));
}
public void ToBytes_ConvertsToBytes_Converted()
{
uint word = 1305570306;
byte[] excepted = { 2, 108, 209, 77 };
CollectionAssert.AreEqual(excepted, Word32Bits.ToBytes(word));
}
public void ToUint_ConvertsToUintLittleEndian_Converted()
{
byte[] bytes = { 2, 108, 209, 77 };
uint excepted = 40685901;
Assert.AreEqual(excepted, Word32Bits.ToUint(bytes, ValueRepresentation.LittleEndian));
}
public static uint h(ITwofishMDS mds, uint x, uint[] L)
{
int k = L.Length;
uint[] y = Word32Bits.ToUintBytes(x);
if (k == 4)
{
y[0] = (uint)q1(y[0]) ^ Word32Bits.GetByte(L[3], 0);
y[1] = (uint)q0(y[1]) ^ Word32Bits.GetByte(L[3], 1);
y[2] = (uint)q0(y[2]) ^ Word32Bits.GetByte(L[3], 2);
y[3] = (uint)q1(y[3]) ^ Word32Bits.GetByte(L[3], 3);
}
if (k >= 3)
{
y[0] = (uint)q1(y[0]) ^ Word32Bits.GetByte(L[2], 0);
y[1] = (uint)q1(y[1]) ^ Word32Bits.GetByte(L[2], 1);
y[2] = (uint)q0(y[2]) ^ Word32Bits.GetByte(L[2], 2);
y[3] = (uint)q0(y[3]) ^ Word32Bits.GetByte(L[2], 3);
}
y[0] = (uint)(q0(q0(y[0]) ^ Word32Bits.GetByte(L[1], 0)) ^ Word32Bits.GetByte(L[0], 0));
y[1] = (uint)(q0(q1(y[1]) ^ Word32Bits.GetByte(L[1], 1)) ^ Word32Bits.GetByte(L[0], 1));
y[2] = (uint)(q1(q0(y[2]) ^ Word32Bits.GetByte(L[1], 2)) ^ Word32Bits.GetByte(L[0], 2));
y[3] = (uint)(q1(q1(y[3]) ^ Word32Bits.GetByte(L[1], 3)) ^ Word32Bits.GetByte(L[0], 3));
return(mds.Multiply(y));
}
public void GetByte_GetsByteFromWord_GotByte()
{
uint value = 1305570306;
Assert.AreEqual(2, Word32Bits.GetByte(value, 0));
Assert.AreEqual(108, Word32Bits.GetByte(value, 1));
Assert.AreEqual(209, Word32Bits.GetByte(value, 2));
Assert.AreEqual(77, Word32Bits.GetByte(value, 3));
}
private uint[] Round(ITwofishMDS mds, uint[] K, int round)
{
uint F0 = TwofishFunction.h(mds, K[0], _key.SBox);
uint F1 = TwofishFunction.h(mds, Word32Bits.RotateLeft(K[1], 8), _key.SBox);
K[2] ^= F0 + F1 + _key.K[2 * round + 8];
K[2] = Word32Bits.RotateRight(K[2], 1);
K[3] = Word32Bits.RotateLeft(K[3], 1) ^ (F0 + 2 * F1 + _key.K[2 * round + 9]);
return(K);
}
private uint ReadWord()
{
var bytes = new byte[_bytesPerWord];
for (int i = 0; i < _bytesPerWord; i++)
{
bytes[i] = ReadByte();
}
return(Word32Bits.ToUint(bytes));
}
private uint[] SplitInto32BitWords(byte[] m)
{
int BYTES_PER_WORD = 4;
var M = new uint[m.Length / BYTES_PER_WORD];
for (int i = 0; i < M.Length; i++)
{
M[i] = Word32Bits.ToUint(m.SubArray(i * 4, i * 4 + 4));
}
return(M);
}
public static uint[] Inverse(uint[] x)
{
uint x1 = Word32Bits.RotateRight(x[2], 22) ^ x[3] ^ x[1] << 7;
uint x2 = Word32Bits.RotateRight(x[0], 5) ^ x[1] ^ x[3];
uint num1 = Word32Bits.RotateRight(x[3], 7);
uint num2 = Word32Bits.RotateRight(x[1], 1);
x[3] = num1 ^ x1 ^ x2 << 3;
x[1] = num2 ^ x2 ^ x1;
x[2] = Word32Bits.RotateRight(x1, 3);
x[0] = Word32Bits.RotateRight(x2, 13);
return(x);
}
private void CalculateWords(uint[] words)
{
for (int i = 8; i < 16; i++)
{
words[i] = Word32Bits.RotateLeft((uint)(words[i - 8] ^ words[i - 5] ^ words[i - 3] ^ words[i - 1] ^ PHI ^ (i - 8)), 11);
}
Array.Copy(words, 8, words, 0, 8);
for (int i = 8; i < 132; i++)
{
words[i] = Word32Bits.RotateLeft((uint)(words[i - 8] ^ words[i - 5] ^ words[i - 3] ^ words[i - 1] ^ PHI ^ i), 11);
}
}
public static uint[] Transform(uint[] x)
{
x[0] = Word32Bits.RotateLeft(x[0], 13);
x[2] = Word32Bits.RotateLeft(x[2], 3);
x[1] = x[1] ^ x[0] ^ x[2];
x[3] = x[3] ^ x[2] ^ x[0] << 3;
x[1] = Word32Bits.RotateLeft(x[1], 1);
x[3] = Word32Bits.RotateLeft(x[3], 7);
x[0] = x[0] ^ x[1] ^ x[3];
x[2] = x[2] ^ x[3] ^ x[1] << 7;
x[0] = Word32Bits.RotateLeft(x[0], 5);
x[2] = Word32Bits.RotateLeft(x[2], 22);
return(x);
}
private uint[] GetK(uint[] Me, uint[] Mo)
{
var k = new uint[40];
uint p = 16843009;
var mds = new TwofishMDS();
for (int i = 0; i < 20; i++)
{
uint A = TwofishFunction.h(mds, (uint)(2 * i * p), Me);
uint B = Word32Bits.RotateLeft(TwofishFunction.h(mds, (uint)((2 * i + 1) * p), Mo), 8);
k[2 * i] = A + B;
k[2 * i + 1] = Word32Bits.RotateLeft(A + 2 * B, 9);
}
return(k);
}
