/* verify_sbox_params.c - Don Yang (uguu.org)

   Check that string encoded by sbox_params.c is usable.

   06/08/12
                                                                           */

#include<stdio.h>

typedef unsigned char Byte;
typedef unsigned int Word;

const char *params =
   "h\32:,<$4~$HhVF+\16tz;Z}8^\1Mt|:0t;^OC|1h|||L|Av>jLt{H*J"
   "H*\nb9]zIcx3hp9n`Nm*?$F-\rzWdN{\4nC&^KEf\33;z0h\0~z25K25"
   "\13Tb{R7\2P8\t04KDNBZo|Lt427J27\n42KT\27\37n'Kb9\rb;\14*"
   "I~PzGPZ!PX\"jg\4.W\16XP;PV\r(ZeRU\16~/.(Xft\22\3h\2=$>BV"
   "aD&%9@.eD,e~u3&[6\10z\rr\32k(X6\n{\rzbmX\"e$J\16|t3&U1 o"
   "JR/9n\t\33,7\13PJ{^\21[Z\23[@\36[p^yB\37[D\32\\P$fj\rzx"
   "\\<vK\2NyMvM\1.%gz!.xTBh\0>,\6Dj[if[;D~BjYj&?B`\16\rR1\5"
   "&1Af[j:_4FiDDhDF9DP>\6@\2aP\6\n4Zv@\0b^}7j\7Mh\4NTr<j\5N"
   "hNkjOkH(KH(\13J}r~>hld<J7|R\31\22R\t\2l\14qXt\35ry=l\nr`"
   "?hR\32\21F\27""7ne<b15*IJ2u>";

/* Reduce bit dependencies */
static void AdjustSingleBitDependencies(Byte *sbox)
{
   int bit, i, j, x;
   Byte current, neighbor, tmp;

   for(bit = 0; bit < 8; bit++)
   {
      for(i = 0; i < 256; i++)
      {
         current = sbox[i];
         neighbor = sbox[i ^ (1 << bit)];
         x = current ^ neighbor;

         if( (x & (x - 1)) == 0 )
         {
            j = i ^ (1 << ((bit + 1) % 8));
            tmp = sbox[i];
            sbox[i] = sbox[j];
            sbox[j] = tmp;
         }
      }
   }
}

/* Initialize sbox from 3 offset parameters */
static void InitSbox(int offset1, int offset2, int offset3, Byte *sbox)
{
   int i, j;

   for(i = 0; i < 256; i++)
   {
      j = ((i + offset1) & 0x7f) | (i & 0x80);
      j = (((j >> 1) + offset2) & 0x7f) | ((j << 7) & 0x80);
      j = (((j >> 1) + offset3) & 0x7f) | ((j << 7) & 0x80);
      sbox[i] = (Byte)j;
   }
   AdjustSingleBitDependencies(sbox);
   AdjustSingleBitDependencies(sbox);
}

#define ROTL32(value, r) \
   (((value) << r) | ((value) >> (32 - r)))

/* Compute hash of sbox */
static Word GetHash(const Byte *sbox)
{
   const Word c1 = 0xcc9e2d51;
   const Word c2 = 0x1b873593;
   Word h = 42;  /* seed */
   Word *data = (Word*)sbox;
   Word k;
   int i;

   for(i = 0; i < 64; i++)
   {
      k = *data++;
      k *= c1;
      k = ROTL32(k, 15);
      k *= c2;
      h ^= k;
      h = ROTL32(h, 13);
      h = h * 5 + 0xe6546b64;
   }
   h ^= h >> 16;
   h *= 0x85ebca6b;
   h ^= h >> 13;
   h *= 0xc2b2ae35;
   h ^= h >> 16;
   return h;
}

int main(/*@unused@*/int argc, /*@unused@*/char **argv)
{
   Byte sbox[256];
   int i;

   for(i = 0; i < 9 * 16 * 3; i += 3)
   {
      InitSbox(params[i] ^ 81, params[i + 1] ^ 25, params[i + 2] ^ 16, sbox);
      printf("%08x\n", GetHash(sbox));
   }
   return 0;
}