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      1 /* Crypto/Sha256.c -- SHA-256 Hash
      2 2010-06-11 : Igor Pavlov : Public domain
      3 This code is based on public domain code from Wei Dai's Crypto++ library. */
      4 
      5 #include "RotateDefs.h"
      6 #include "Sha256.h"
      7 
      8 /* define it for speed optimization */
      9 /* #define _SHA256_UNROLL */
     10 /* #define _SHA256_UNROLL2 */
     11 
     12 void Sha256_Init(CSha256 *p)
     13 {
     14   p->state[0] = 0x6a09e667;
     15   p->state[1] = 0xbb67ae85;
     16   p->state[2] = 0x3c6ef372;
     17   p->state[3] = 0xa54ff53a;
     18   p->state[4] = 0x510e527f;
     19   p->state[5] = 0x9b05688c;
     20   p->state[6] = 0x1f83d9ab;
     21   p->state[7] = 0x5be0cd19;
     22   p->count = 0;
     23 }
     24 
     25 #define S0(x) (rotrFixed(x, 2) ^ rotrFixed(x,13) ^ rotrFixed(x, 22))
     26 #define S1(x) (rotrFixed(x, 6) ^ rotrFixed(x,11) ^ rotrFixed(x, 25))
     27 #define s0(x) (rotrFixed(x, 7) ^ rotrFixed(x,18) ^ (x >> 3))
     28 #define s1(x) (rotrFixed(x,17) ^ rotrFixed(x,19) ^ (x >> 10))
     29 
     30 #define blk0(i) (W[i] = data[i])
     31 #define blk2(i) (W[i&15] += s1(W[(i-2)&15]) + W[(i-7)&15] + s0(W[(i-15)&15]))
     32 
     33 #define Ch(x,y,z) (z^(x&(y^z)))
     34 #define Maj(x,y,z) ((x&y)|(z&(x|y)))
     35 
     36 #define a(i) T[(0-(i))&7]
     37 #define b(i) T[(1-(i))&7]
     38 #define c(i) T[(2-(i))&7]
     39 #define d(i) T[(3-(i))&7]
     40 #define e(i) T[(4-(i))&7]
     41 #define f(i) T[(5-(i))&7]
     42 #define g(i) T[(6-(i))&7]
     43 #define h(i) T[(7-(i))&7]
     44 
     45 
     46 #ifdef _SHA256_UNROLL2
     47 
     48 #define R(a,b,c,d,e,f,g,h, i) h += S1(e) + Ch(e,f,g) + K[i+j] + (j?blk2(i):blk0(i));\
     49   d += h; h += S0(a) + Maj(a, b, c)
     50 
     51 #define RX_8(i) \
     52   R(a,b,c,d,e,f,g,h, i); \
     53   R(h,a,b,c,d,e,f,g, i+1); \
     54   R(g,h,a,b,c,d,e,f, i+2); \
     55   R(f,g,h,a,b,c,d,e, i+3); \
     56   R(e,f,g,h,a,b,c,d, i+4); \
     57   R(d,e,f,g,h,a,b,c, i+5); \
     58   R(c,d,e,f,g,h,a,b, i+6); \
     59   R(b,c,d,e,f,g,h,a, i+7)
     60 
     61 #else
     62 
     63 #define R(i) h(i) += S1(e(i)) + Ch(e(i),f(i),g(i)) + K[i+j] + (j?blk2(i):blk0(i));\
     64   d(i) += h(i); h(i) += S0(a(i)) + Maj(a(i), b(i), c(i))
     65 
     66 #ifdef _SHA256_UNROLL
     67 
     68 #define RX_8(i) R(i+0); R(i+1); R(i+2); R(i+3); R(i+4); R(i+5); R(i+6); R(i+7);
     69 
     70 #endif
     71 
     72 #endif
     73 
     74 static const UInt32 K[64] = {
     75   0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5,
     76   0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
     77   0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
     78   0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
     79   0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc,
     80   0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
     81   0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7,
     82   0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
     83   0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,
     84   0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
     85   0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3,
     86   0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
     87   0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5,
     88   0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
     89   0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
     90   0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2
     91 };
     92 
     93 static void Sha256_Transform(UInt32 *state, const UInt32 *data)
     94 {
     95   UInt32 W[16];
     96   unsigned j;
     97   #ifdef _SHA256_UNROLL2
     98   UInt32 a,b,c,d,e,f,g,h;
     99   a = state[0];
    100   b = state[1];
    101   c = state[2];
    102   d = state[3];
    103   e = state[4];
    104   f = state[5];
    105   g = state[6];
    106   h = state[7];
    107   #else
    108   UInt32 T[8];
    109   for (j = 0; j < 8; j++)
    110     T[j] = state[j];
    111   #endif
    112 
    113   for (j = 0; j < 64; j += 16)
    114   {
    115     #if defined(_SHA256_UNROLL) || defined(_SHA256_UNROLL2)
    116     RX_8(0); RX_8(8);
    117     #else
    118     unsigned i;
    119     for (i = 0; i < 16; i++) { R(i); }
    120     #endif
    121   }
    122 
    123   #ifdef _SHA256_UNROLL2
    124   state[0] += a;
    125   state[1] += b;
    126   state[2] += c;
    127   state[3] += d;
    128   state[4] += e;
    129   state[5] += f;
    130   state[6] += g;
    131   state[7] += h;
    132   #else
    133   for (j = 0; j < 8; j++)
    134     state[j] += T[j];
    135   #endif
    136 
    137   /* Wipe variables */
    138   /* memset(W, 0, sizeof(W)); */
    139   /* memset(T, 0, sizeof(T)); */
    140 }
    141 
    142 #undef S0
    143 #undef S1
    144 #undef s0
    145 #undef s1
    146 
    147 static void Sha256_WriteByteBlock(CSha256 *p)
    148 {
    149   UInt32 data32[16];
    150   unsigned i;
    151   for (i = 0; i < 16; i++)
    152     data32[i] =
    153       ((UInt32)(p->buffer[i * 4    ]) << 24) +
    154       ((UInt32)(p->buffer[i * 4 + 1]) << 16) +
    155       ((UInt32)(p->buffer[i * 4 + 2]) <<  8) +
    156       ((UInt32)(p->buffer[i * 4 + 3]));
    157   Sha256_Transform(p->state, data32);
    158 }
    159 
    160 void Sha256_Update(CSha256 *p, const Byte *data, size_t size)
    161 {
    162   UInt32 curBufferPos = (UInt32)p->count & 0x3F;
    163   while (size > 0)
    164   {
    165     p->buffer[curBufferPos++] = *data++;
    166     p->count++;
    167     size--;
    168     if (curBufferPos == 64)
    169     {
    170       curBufferPos = 0;
    171       Sha256_WriteByteBlock(p);
    172     }
    173   }
    174 }
    175 
    176 void Sha256_Final(CSha256 *p, Byte *digest)
    177 {
    178   UInt64 lenInBits = (p->count << 3);
    179   UInt32 curBufferPos = (UInt32)p->count & 0x3F;
    180   unsigned i;
    181   p->buffer[curBufferPos++] = 0x80;
    182   while (curBufferPos != (64 - 8))
    183   {
    184     curBufferPos &= 0x3F;
    185     if (curBufferPos == 0)
    186       Sha256_WriteByteBlock(p);
    187     p->buffer[curBufferPos++] = 0;
    188   }
    189   for (i = 0; i < 8; i++)
    190   {
    191     p->buffer[curBufferPos++] = (Byte)(lenInBits >> 56);
    192     lenInBits <<= 8;
    193   }
    194   Sha256_WriteByteBlock(p);
    195 
    196   for (i = 0; i < 8; i++)
    197   {
    198     *digest++ = (Byte)(p->state[i] >> 24);
    199     *digest++ = (Byte)(p->state[i] >> 16);
    200     *digest++ = (Byte)(p->state[i] >> 8);
    201     *digest++ = (Byte)(p->state[i]);
    202   }
    203   Sha256_Init(p);
    204 }
    205