/* Threefish-1024 LITE-port from Java implementation of Skein by Maarten Bodewes *//*                        Alexander Myasnikov                                    *//*                 WEB:  www.darksoftware.narod.ru                               */#include <mem.h>#define u64    unsigned long longconst u64 EXTENDED_KEY_SCHEDULE_CONST = 6148914691236517205L;int SUBKEY_INTERVAL = 4;//  Word permutation constants for PI(i)int PI16[16] = { 0, 9, 2, 13, 6, 11, 4, 15, 10, 7, 12, 3, 14, 5, 8, 1 };//  Reverse word permutation constants for PI(i)int RPI16[16] = { 0, 15, 2, 11, 6, 13, 4, 9, 14, 1, 8, 5, 10, 3, 12, 7 };int DEPTH_OF_D_IN_R = 8;// Rotation constantsint R16[8][8] ={   { 55, 43, 37, 40, 16, 22, 38, 12 },   { 25, 25, 46, 13, 14, 13, 52, 57 },   { 33,  8, 18, 57, 21, 12, 32, 54 },   { 34, 43, 25, 60, 44,  9, 59, 34 },   { 28,  7, 47, 48, 51,  9, 35, 41 },   { 17,  6, 18, 25, 43, 42, 40, 15 },   { 58,  7, 32, 45, 19, 18,  2, 56 },   { 47, 49, 27, 58, 37, 48, 53, 56 },};u64 t[3];u64 x[2];u64 y[2];int nr = 80;                    // number of rounds depending on block sizeu64 k[17];                      // initial key words including knwint nw = 16;                    // number of key words excluding knwu64 vd[16];u64 ed[16];u64 fd[16];u64 ksd[16];#define rol64(x, n)    ((x << (n)) | (x >> (64 - n)))#define ror64(x, n)    (x >> n) | (x << (64 - n))// param j the index in the rotation constants// param d the roundvoidmix(int j, int d){   u64 rotl;   y[0]  = x[0] + x[1];   rotl  = R16[d % DEPTH_OF_D_IN_R][j];   y[1]  = rol64(x[1], rotl);   y[1] ^= y[0];}voiddemix(int j, int d){   u64 rotr;   y[1] ^= y[0];   rotr  = R16[d % DEPTH_OF_D_IN_R][j]; // NOTE performance: darn, creation on stack!   x[1]  = ror64(y[1], rotr);   x[0]  = y[0] - x[1];}voidkeySchedule(int s){   int i;   for (i = 0; i < nw; i++)   {      // just put in the main key first      ksd[i] = k[(s + i) % (nw + 1)];      // don't add anything for i = 0,...,Nw - 4      if (i == nw - 3)          // second to last      {         ksd[i] += t[s % 3];      }      else if (i == nw - 2)     // first to last      {         ksd[i] += t[(s + 1) % 3];      }      else if (i == nw - 1)     // last      {         ksd[i] += s;      }   }}voidinit(u64 *key, u64 *tweak){   int i;   u64 knw;   memset(vd, 0, 128);   memset(ed, 0, 128);   memset(fd, 0, 128);   memset(ksd, 0, 128);   for (i = 0; i < nw; i++)   {      k[i] = key[i];   }   knw = EXTENDED_KEY_SCHEDULE_CONST;   for (i = 0; i < nw; i++)   {      knw ^= key[i];   }   k[nw] = knw;   // set tweak values   t[0] = tweak[0];   t[1] = tweak[1];   t[2] = t[0] ^ t[1];}void __stdcall __exportcrypt(u64 *p, u64 *c){   int i, d, j, s;   for (i = 0; i < nw; i++)   {      vd[i] = p[i];   }   for (d = 0; d < nr; d++)     // do the rounds   {      // calculate e{d,i}      if (d % SUBKEY_INTERVAL == 0)      {         s = d / SUBKEY_INTERVAL;         keySchedule(s);         for (i = 0; i < nw; i++)         {            ed[i] = vd[i] + ksd[i];         }      }      else      {         for (i = 0; i < nw; i++)         {            ed[i] = vd[i];         }      }      for (j = 0; j < nw / 2; j++)      {         x[0] = ed[j * 2];         x[1] = ed[j * 2 + 1];         mix(j, d);         fd[j * 2]     = y[0];         fd[j * 2 + 1] = y[1];      }      for (i = 0; i < nw; i++)      {         vd[i] = fd[PI16[i]];      }   }   // do the last keyschedule   keySchedule(nr / SUBKEY_INTERVAL);   for (i = 0; i < nw; i++)   {      c[i] = vd[i] + ksd[i];   }}void __stdcall __exportdecrypt(u64 *c, u64 *p){   int i, d, j, s;   // initial value = plain   for (i = 0; i < nw; i++)   {      vd[i] = c[i];   }   for (d = nr; d > 0; d--)     // do the rounds   {      // calculate e{d,i}      if (d % SUBKEY_INTERVAL == 0)      {         s = d / SUBKEY_INTERVAL;         keySchedule(s);        // calculate same keys         for (i = 0; i < nw; i++)         {            fd[i] = vd[i] - ksd[i];         }      }      else      {         for (i = 0; i < nw; i++)         {            fd[i] = vd[i];         }      }      for (i = 0; i < nw; i++)      {         ed[i] = fd[RPI16[i]];      }      for (j = 0; j < nw / 2; j++)      {         y[0] = ed[j * 2];         y[1] = ed[j * 2 + 1];         demix(j, d - 1);         vd[j * 2]     = x[0];         vd[j * 2 + 1] = x[1];      }   }   // do the first keyschedule   keySchedule(0);   for (i = 0; i < nw; i++)   {      p[i] = vd[i] - ksd[i];   }}void __stdcall __exportsetup(u64 *key, u64 *tweak){   init(key, tweak);}