Created
April 22, 2015 17:38
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Flawed shuffle code - what is wrong with this?
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internal static byte[,] shuffle_order = new byte[,] | |
{{0,1,2,3},{0,1,3,2},{0,2,1,3},{0,2,3,1},{0,3,1,2},{0,3,2,1},{1,0,2,3},{1,0,3,2}, | |
{1,2,0,3},{1,2,3,0},{1,3,0,2},{1,3,2,0},{2,0,1,3},{2,0,3,1},{2,1,0,3},{2,1,3,0},{2,3,0,1}, | |
{2,3,1,0},{3,0,1,2},{3,0,2,1},{3,1,0,2},{3,1,2,0},{3,2,0,1},{3,2,1,0}}; | |
internal static byte[,] inv_shuffle_order = new byte[,] | |
{{0,1,2,3},{0,1,3,2},{0,2,1,3},{0,3,1,2},{0,2,3,1},{0,3,2,1},{1,0,2,3},{1,0,3,2},{2,0,1,3}, | |
{3,0,1,2},{2,0,3,1},{3,0,2,1},{1,2,0,3},{1,3,0,2},{2,1,0,3},{3,1,0,2},{2,3,0,1},{3,2,0,1}, | |
{1,2,3,0},{1,3,2,0},{2,1,3,0},{3,1,2,0},{2,3,1,0},{3,2,1,0}}; | |
internal static byte[] shuffle(byte[] pkx, bool un) | |
{ | |
byte[] temp = new byte[232]; | |
Array.Clear(temp, 0, 232); | |
uint pv = BitConverter.ToUInt32(pkx, 0); | |
uint sv = ((pv & 0x3E000) >> 0xD) % 24; | |
const int blocksize = 56; | |
if (un) | |
{ | |
Array.Copy(pkx, 8 + (0 * blocksize), temp, 8 + (shuffle_order[sv, 0] * blocksize), blocksize); | |
Array.Copy(pkx, 8 + (1 * blocksize), temp, 8 + (shuffle_order[sv, 1] * blocksize), blocksize); | |
Array.Copy(pkx, 8 + (2 * blocksize), temp, 8 + (shuffle_order[sv, 2] * blocksize), blocksize); | |
Array.Copy(pkx, 8 + (3 * blocksize), temp, 8 + (shuffle_order[sv, 3] * blocksize), blocksize); | |
} | |
else | |
{ | |
Array.Copy(pkx, 8 + (0 * blocksize), temp, 8 + (inv_shuffle_order[sv, 0] * blocksize), blocksize); | |
Array.Copy(pkx, 8 + (1 * blocksize), temp, 8 + (inv_shuffle_order[sv, 1] * blocksize), blocksize); | |
Array.Copy(pkx, 8 + (2 * blocksize), temp, 8 + (inv_shuffle_order[sv, 2] * blocksize), blocksize); | |
Array.Copy(pkx, 8 + (3 * blocksize), temp, 8 + (inv_shuffle_order[sv, 3] * blocksize), blocksize); | |
} | |
Array.Copy(temp, 8, pkx, 8, 224); | |
return pkx; | |
} |
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I think you've got the offsets in the Copy call swapped.