skalibs

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blake2s_transform.c (2419B)

      1  /* ISC license. */
      2 
      3 #include <stdint.h>
      4 
      5 #include <skalibs/uint32.h>
      6 #include <skalibs/blake2s.h>
      7 #include "blake2s-internal.h"
      8 
      9 static uint32_t const blake2s_iv[8] =
     10 {
     11   0x6A09E667UL, 0xBB67AE85UL, 0x3C6EF372UL, 0xA54FF53AUL,
     12   0x510E527FUL, 0x9B05688CUL, 0x1F83D9ABUL, 0x5BE0CD19UL
     13 };
     14 
     15 static uint8_t const blake2s_sigma[10][16] =
     16 {
     17   { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 },
     18   { 14, 10, 4, 8, 9, 15, 13, 6, 1, 12, 0, 2, 11, 7, 5, 3 },
     19   { 11, 8, 12, 0, 5, 2, 15, 13, 10, 14, 3, 6, 7, 1, 9, 4 },
     20   { 7, 9, 3, 1, 13, 12, 11, 14, 2, 6, 5, 10, 4, 0, 15, 8 },
     21   { 9, 0, 5, 7, 2, 4, 10, 15, 14, 1, 11, 12, 6, 8, 3, 13 },
     22   { 2, 12, 6, 10, 0, 11, 8, 3, 4, 13, 7, 5, 15, 14, 1, 9 },
     23   { 12, 5, 1, 15, 14, 13, 4, 10, 0, 7, 6, 3, 9, 2, 8, 11 },
     24   { 13, 11, 7, 14, 12, 1, 3, 9, 5, 0, 15, 4, 8, 6, 2, 10 },
     25   { 6, 15, 14, 9, 11, 3, 0, 8, 12, 2, 13, 7, 1, 4, 10, 5 },
     26   { 10, 2, 8, 4, 7, 6, 1, 5, 15, 11, 9, 14, 3, 12, 13, 0 }
     27 } ;
     28 
     29 static uint32_t ror32 (uint32_t word, unsigned int shift)
     30 {
     31   return (word >> (shift & 31)) | (word << ((-shift) & 31)) ;
     32 }
     33 
     34 #define G(r, i, a, b, c, d) do \
     35 { \
     36   a += b + m[blake2s_sigma[r][i<<1]] ; \
     37   d = ror32(d ^ a, 16) ; \
     38   c += d ; \
     39   b = ror32(b ^ c, 12) ; \
     40   a += b + m[blake2s_sigma[r][(i<<1)+1]] ; \
     41   d = ror32(d ^ a, 8) ; \
     42   c += d ; \
     43   b = ror32(b ^ c, 7) ; \
     44 } while (0)
     45 
     46 void blake2s_transform (blake2s_ctx *ctx, char const *block, size_t n, uint32_t inc)
     47 {
     48   uint32_t m[16] ;
     49   uint32_t v[16] ;
     50 
     51   while (n--)
     52   {
     53     unsigned int i = 0 ;
     54     ctx->t[0] += inc ;
     55     ctx->t[1] += (ctx->t[0] < inc) ;
     56     for (; i < 16 ; i++) uint32_unpack(block + (i << 2), m + i) ;
     57     for (i = 0 ; i < 8 ; i++) v[i] = ctx->h[i] ;
     58     v[8] = blake2s_iv[0] ;
     59     v[9] = blake2s_iv[1] ;
     60     v[10] = blake2s_iv[2] ;
     61     v[11] = blake2s_iv[3] ;
     62     v[12] = blake2s_iv[4] ^ ctx->t[0] ;
     63     v[13] = blake2s_iv[5] ^ ctx->t[1] ;
     64     v[14] = blake2s_iv[6] ^ ctx->f[0] ;
     65     v[15] = blake2s_iv[7] ^ ctx->f[1] ;
     66 
     67     for (i = 0 ; i < 10 ; i++)
     68     {
     69       G(i, 0, v[0], v[ 4], v[ 8], v[12]) ;
     70       G(i, 1, v[1], v[ 5], v[ 9], v[13]) ;
     71       G(i, 2, v[2], v[ 6], v[10], v[14]) ;
     72       G(i, 3, v[3], v[ 7], v[11], v[15]) ;
     73       G(i, 4, v[0], v[ 5], v[10], v[15]) ;
     74       G(i, 5, v[1], v[ 6], v[11], v[12]) ;
     75       G(i, 6, v[2], v[ 7], v[ 8], v[13]) ;
     76       G(i, 7, v[3], v[ 4], v[ 9], v[14]) ;
     77     }
     78 
     79     for (i = 0 ; i < 8 ; i++) ctx->h[i] ^= v[i] ^ v[i+8] ;
     80     block += 64 ;
     81   }
     82 }