private void DecryptBlock(
byte[] input,
int inOff,
byte[] outBytes,
int outOff)
{
int x76, x54, x32, x10;
x76 = ((input[inOff + 7] & 0xff) << 8) + (input[inOff + 6] & 0xff);
x54 = ((input[inOff + 5] & 0xff) << 8) + (input[inOff + 4] & 0xff);
x32 = ((input[inOff + 3] & 0xff) << 8) + (input[inOff + 2] & 0xff);
x10 = ((input[inOff + 1] & 0xff) << 8) + (input[inOff + 0] & 0xff);
for (int i = 60; i >= 44; i -= 4)
{
x76 = RotateWordLeft(x76, 11) - ((x10 & ~x54) + (x32 & x54) + workingKey[i+3]);
x54 = RotateWordLeft(x54, 13) - ((x76 & ~x32) + (x10 & x32) + workingKey[i+2]);
x32 = RotateWordLeft(x32, 14) - ((x54 & ~x10) + (x76 & x10) + workingKey[i+1]);
x10 = RotateWordLeft(x10, 15) - ((x32 & ~x76) + (x54 & x76) + workingKey[i ]);
}
x76 -= workingKey[x54 & 63];
x54 -= workingKey[x32 & 63];
x32 -= workingKey[x10 & 63];
x10 -= workingKey[x76 & 63];
for (int i = 40; i >= 20; i -= 4)
{
x76 = RotateWordLeft(x76, 11) - ((x10 & ~x54) + (x32 & x54) + workingKey[i+3]);
x54 = RotateWordLeft(x54, 13) - ((x76 & ~x32) + (x10 & x32) + workingKey[i+2]);
x32 = RotateWordLeft(x32, 14) - ((x54 & ~x10) + (x76 & x10) + workingKey[i+1]);
x10 = RotateWordLeft(x10, 15) - ((x32 & ~x76) + (x54 & x76) + workingKey[i ]);
}
x76 -= workingKey[x54 & 63];
x54 -= workingKey[x32 & 63];
x32 -= workingKey[x10 & 63];
x10 -= workingKey[x76 & 63];
for (int i = 16; i >= 0; i -= 4)
{
x76 = RotateWordLeft(x76, 11) - ((x10 & ~x54) + (x32 & x54) + workingKey[i+3]);
x54 = RotateWordLeft(x54, 13) - ((x76 & ~x32) + (x10 & x32) + workingKey[i+2]);
x32 = RotateWordLeft(x32, 14) - ((x54 & ~x10) + (x76 & x10) + workingKey[i+1]);
x10 = RotateWordLeft(x10, 15) - ((x32 & ~x76) + (x54 & x76) + workingKey[i ]);
}
outBytes[outOff + 0] = (byte)x10;
outBytes[outOff + 1] = (byte)(x10 >> 8);
outBytes[outOff + 2] = (byte)x32;
outBytes[outOff + 3] = (byte)(x32 >> 8);
outBytes[outOff + 4] = (byte)x54;
outBytes[outOff + 5] = (byte)(x54 >> 8);
outBytes[outOff + 6] = (byte)x76;
outBytes[outOff + 7] = (byte)(x76 >> 8);
}
}
