sha256/block/sha256.c

   1 #include "git-compat-util.h"
   2 #include "./sha256.h"
   3
   4 #undef RND
   5 #undef BLKSIZE
   6
   7 #define BLKSIZE blk_SHA256_BLKSIZE
   8
   9 void blk_SHA256_Init(blk_SHA256_CTX *ctx)
  10 {
  11         ctx->offset = 0;
  12         ctx->size = 0;
  13         ctx->state[0] = 0x6a09e667ul;
  14         ctx->state[1] = 0xbb67ae85ul;
  15         ctx->state[2] = 0x3c6ef372ul;
  16         ctx->state[3] = 0xa54ff53aul;
  17         ctx->state[4] = 0x510e527ful;
  18         ctx->state[5] = 0x9b05688cul;
  19         ctx->state[6] = 0x1f83d9abul;
  20         ctx->state[7] = 0x5be0cd19ul;
  21 }
  22
  23 static inline uint32_t ror(uint32_t x, unsigned n)
  24 {
  25         return (x >> n) | (x << (32 - n));
  26 }
  27
  28 static inline uint32_t ch(uint32_t x, uint32_t y, uint32_t z)
  29 {
  30         return z ^ (x & (y ^ z));
  31 }
  32
  33 static inline uint32_t maj(uint32_t x, uint32_t y, uint32_t z)
  34 {
  35         return ((x | y) & z) | (x & y);
  36 }
  37
  38 static inline uint32_t sigma0(uint32_t x)
  39 {
  40         return ror(x, 2) ^ ror(x, 13) ^ ror(x, 22);
  41 }
  42
  43 static inline uint32_t sigma1(uint32_t x)
  44 {
  45         return ror(x, 6) ^ ror(x, 11) ^ ror(x, 25);
  46 }
  47
  48 static inline uint32_t gamma0(uint32_t x)
  49 {
  50         return ror(x, 7) ^ ror(x, 18) ^ (x >> 3);
  51 }
  52
  53 static inline uint32_t gamma1(uint32_t x)
  54 {
  55         return ror(x, 17) ^ ror(x, 19) ^ (x >> 10);
  56 }
  57
  58 static void blk_SHA256_Transform(blk_SHA256_CTX *ctx, const unsigned char *buf)
  59 {
  60
  61         uint32_t S[8], W[64], t0, t1;
  62         int i;
  63
  64         /* copy state into S */
  65         for (i = 0; i < 8; i++)
  66                 S[i] = ctx->state[i];
  67
  68         /* copy the state into 512-bits into W[0..15] */
  69         for (i = 0; i < 16; i++, buf += sizeof(uint32_t))
  70                 W[i] = get_be32(buf);
  71
  72         /* fill W[16..63] */
  73         for (i = 16; i < 64; i++)
  74                 W[i] = gamma1(W[i - 2]) + W[i - 7] + gamma0(W[i - 15]) + W[i - 16];
  75
  76 #define RND(a,b,c,d,e,f,g,h,i,ki)                    \
  77         t0 = h + sigma1(e) + ch(e, f, g) + ki + W[i];   \
  78         t1 = sigma0(a) + maj(a, b, c);                  \
  79         d += t0;                                        \
  80         h  = t0 + t1;
  81
  82         RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],0,0x428a2f98);
  83         RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],1,0x71374491);
  84         RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],2,0xb5c0fbcf);
  85         RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],3,0xe9b5dba5);
  86         RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],4,0x3956c25b);
  87         RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],5,0x59f111f1);
  88         RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],6,0x923f82a4);
  89         RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],7,0xab1c5ed5);
  90         RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],8,0xd807aa98);
  91         RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],9,0x12835b01);
  92         RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],10,0x243185be);
  93         RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],11,0x550c7dc3);
  94         RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],12,0x72be5d74);
  95         RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],13,0x80deb1fe);
  96         RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],14,0x9bdc06a7);
  97         RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],15,0xc19bf174);
  98         RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],16,0xe49b69c1);
  99         RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],17,0xefbe4786);
 100         RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],18,0x0fc19dc6);
 101         RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],19,0x240ca1cc);
 102         RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],20,0x2de92c6f);
 103         RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],21,0x4a7484aa);
 104         RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],22,0x5cb0a9dc);
 105         RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],23,0x76f988da);
 106         RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],24,0x983e5152);
 107         RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],25,0xa831c66d);
 108         RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],26,0xb00327c8);
 109         RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],27,0xbf597fc7);
 110         RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],28,0xc6e00bf3);
 111         RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],29,0xd5a79147);
 112         RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],30,0x06ca6351);
 113         RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],31,0x14292967);
 114         RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],32,0x27b70a85);
 115         RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],33,0x2e1b2138);
 116         RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],34,0x4d2c6dfc);
 117         RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],35,0x53380d13);
 118         RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],36,0x650a7354);
 119         RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],37,0x766a0abb);
 120         RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],38,0x81c2c92e);
 121         RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],39,0x92722c85);
 122         RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],40,0xa2bfe8a1);
 123         RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],41,0xa81a664b);
 124         RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],42,0xc24b8b70);
 125         RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],43,0xc76c51a3);
 126         RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],44,0xd192e819);
 127         RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],45,0xd6990624);
 128         RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],46,0xf40e3585);
 129         RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],47,0x106aa070);
 130         RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],48,0x19a4c116);
 131         RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],49,0x1e376c08);
 132         RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],50,0x2748774c);
 133         RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],51,0x34b0bcb5);
 134         RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],52,0x391c0cb3);
 135         RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],53,0x4ed8aa4a);
 136         RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],54,0x5b9cca4f);
 137         RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],55,0x682e6ff3);
 138         RND(S[0],S[1],S[2],S[3],S[4],S[5],S[6],S[7],56,0x748f82ee);
 139         RND(S[7],S[0],S[1],S[2],S[3],S[4],S[5],S[6],57,0x78a5636f);
 140         RND(S[6],S[7],S[0],S[1],S[2],S[3],S[4],S[5],58,0x84c87814);
 141         RND(S[5],S[6],S[7],S[0],S[1],S[2],S[3],S[4],59,0x8cc70208);
 142         RND(S[4],S[5],S[6],S[7],S[0],S[1],S[2],S[3],60,0x90befffa);
 143         RND(S[3],S[4],S[5],S[6],S[7],S[0],S[1],S[2],61,0xa4506ceb);
 144         RND(S[2],S[3],S[4],S[5],S[6],S[7],S[0],S[1],62,0xbef9a3f7);
 145         RND(S[1],S[2],S[3],S[4],S[5],S[6],S[7],S[0],63,0xc67178f2);
 146
 147         for (i = 0; i < 8; i++)
 148                 ctx->state[i] += S[i];
 149 }
 150
 151 void blk_SHA256_Update(blk_SHA256_CTX *ctx, const void *data, size_t len)
 152 {
 153         unsigned int len_buf = ctx->size & 63;
 154
 155         ctx->size += len;
 156
 157         /* Read the data into buf and process blocks as they get full */
 158         if (len_buf) {
 159                 unsigned int left = 64 - len_buf;
 160                 if (len < left)
 161                         left = len;
 162                 memcpy(len_buf + ctx->buf, data, left);
 163                 len_buf = (len_buf + left) & 63;
 164                 len -= left;
 165                 data = ((const char *)data + left);
 166                 if (len_buf)
 167                         return;
 168                 blk_SHA256_Transform(ctx, ctx->buf);
 169         }
 170         while (len >= 64) {
 171                 blk_SHA256_Transform(ctx, data);
 172                 data = ((const char *)data + 64);
 173                 len -= 64;
 174         }
 175         if (len)
 176                 memcpy(ctx->buf, data, len);
 177 }
 178
 179 void blk_SHA256_Final(unsigned char *digest, blk_SHA256_CTX *ctx)
 180 {
 181         static const unsigned char pad[64] = { 0x80 };
 182         unsigned int padlen[2];
 183         int i;
 184
 185         /* Pad with a binary 1 (ie 0x80), then zeroes, then length */
 186         padlen[0] = htonl((uint32_t)(ctx->size >> 29));
 187         padlen[1] = htonl((uint32_t)(ctx->size << 3));
 188
 189         i = ctx->size & 63;
 190         blk_SHA256_Update(ctx, pad, 1 + (63 & (55 - i)));
 191         blk_SHA256_Update(ctx, padlen, 8);
 192
 193         /* copy output */
 194         for (i = 0; i < 8; i++, digest += sizeof(uint32_t))
 195                 put_be32(digest, ctx->state[i]);
 196 }