providers/implementations/digests/blake2s_prov.c

   1 /*
   2  * Copyright 2016-2021 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the Apache License 2.0 (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 /*
  11  * Derived from the BLAKE2 reference implementation written by Samuel Neves.
  12  * Copyright 2012, Samuel Neves <sneves@dei.uc.pt>
  13  * More information about the BLAKE2 hash function and its implementations
  14  * can be found at https://blake2.net.
  15  */
  16
  17 #include <assert.h>
  18 #include <string.h>
  19 #include <openssl/crypto.h>
  20 #include "blake2_impl.h"
  21 #include "prov/blake2.h"
  22
  23 static const uint32_t blake2s_IV[8] =
  24 {
  25     0x6A09E667U, 0xBB67AE85U, 0x3C6EF372U, 0xA54FF53AU,
  26     0x510E527FU, 0x9B05688CU, 0x1F83D9ABU, 0x5BE0CD19U
  27 };
  28
  29 static const uint8_t blake2s_sigma[10][16] =
  30 {
  31     {  0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15 } ,
  32     { 14, 10,  4,  8,  9, 15, 13,  6,  1, 12,  0,  2, 11,  7,  5,  3 } ,
  33     { 11,  8, 12,  0,  5,  2, 15, 13, 10, 14,  3,  6,  7,  1,  9,  4 } ,
  34     {  7,  9,  3,  1, 13, 12, 11, 14,  2,  6,  5, 10,  4,  0, 15,  8 } ,
  35     {  9,  0,  5,  7,  2,  4, 10, 15, 14,  1, 11, 12,  6,  8,  3, 13 } ,
  36     {  2, 12,  6, 10,  0, 11,  8,  3,  4, 13,  7,  5, 15, 14,  1,  9 } ,
  37     { 12,  5,  1, 15, 14, 13,  4, 10,  0,  7,  6,  3,  9,  2,  8, 11 } ,
  38     { 13, 11,  7, 14, 12,  1,  3,  9,  5,  0, 15,  4,  8,  6,  2, 10 } ,
  39     {  6, 15, 14,  9, 11,  3,  0,  8, 12,  2, 13,  7,  1,  4, 10,  5 } ,
  40     { 10,  2,  8,  4,  7,  6,  1,  5, 15, 11,  9, 14,  3, 12, 13 , 0 } ,
  41 };
  42
  43 /* Set that it's the last block we'll compress */
  44 static ossl_inline void blake2s_set_lastblock(BLAKE2S_CTX *S)
  45 {
  46     S->f[0] = -1;
  47 }
  48
  49 /* Initialize the hashing state. */
  50 static ossl_inline void blake2s_init0(BLAKE2S_CTX *S)
  51 {
  52     int i;
  53
  54     memset(S, 0, sizeof(BLAKE2S_CTX));
  55     for (i = 0; i < 8; ++i) {
  56         S->h[i] = blake2s_IV[i];
  57     }
  58 }
  59
  60 /* init xors IV with input parameter block and sets the output length */
  61 static void blake2s_init_param(BLAKE2S_CTX *S, const BLAKE2S_PARAM *P)
  62 {
  63     size_t i;
  64     const uint8_t *p = (const uint8_t *)(P);
  65
  66     blake2s_init0(S);
  67     S->outlen = P->digest_length;
  68
  69     /* The param struct is carefully hand packed, and should be 32 bytes on
  70      * every platform. */
  71     assert(sizeof(BLAKE2S_PARAM) == 32);
  72     /* IV XOR ParamBlock */
  73     for (i = 0; i < 8; ++i) {
  74         S->h[i] ^= load32(&p[i*4]);
  75     }
  76 }
  77
  78 void ossl_blake2s_param_init(BLAKE2S_PARAM *P)
  79 {
  80     P->digest_length = BLAKE2S_DIGEST_LENGTH;
  81     P->key_length    = 0;
  82     P->fanout        = 1;
  83     P->depth         = 1;
  84     store32(P->leaf_length, 0);
  85     store48(P->node_offset, 0);
  86     P->node_depth    = 0;
  87     P->inner_length  = 0;
  88     memset(P->salt,     0, sizeof(P->salt));
  89     memset(P->personal, 0, sizeof(P->personal));
  90 }
  91
  92 void ossl_blake2s_param_set_digest_length(BLAKE2S_PARAM *P, uint8_t outlen)
  93 {
  94     P->digest_length = outlen;
  95 }
  96
  97 void ossl_blake2s_param_set_key_length(BLAKE2S_PARAM *P, uint8_t keylen)
  98 {
  99     P->key_length = keylen;
 100 }
 101
 102 void ossl_blake2s_param_set_personal(BLAKE2S_PARAM *P, const uint8_t *personal,
 103                                      size_t len)
 104 {
 105     memcpy(P->personal, personal, len);
 106     memset(P->personal + len, 0, BLAKE2S_PERSONALBYTES - len);
 107 }
 108
 109 void ossl_blake2s_param_set_salt(BLAKE2S_PARAM *P, const uint8_t *salt,
 110                                  size_t len)
 111 {
 112     memcpy(P->salt, salt, len);
 113     memset(P->salt + len, 0, BLAKE2S_SALTBYTES - len);}
 114
 115 /*
 116  * Initialize the hashing context with the given parameter block.
 117  * Always returns 1.
 118  */
 119 int ossl_blake2s_init(BLAKE2S_CTX *c, const BLAKE2S_PARAM *P)
 120 {
 121     blake2s_init_param(c, P);
 122     return 1;
 123 }
 124
 125 /*
 126  * Initialize the hashing context with the given parameter block and key.
 127  * Always returns 1.
 128  */
 129 int ossl_blake2s_init_key(BLAKE2S_CTX *c, const BLAKE2S_PARAM *P,
 130                           const void *key)
 131 {
 132     blake2s_init_param(c, P);
 133
 134     /* Pad the key to form first data block */
 135     {
 136         uint8_t block[BLAKE2S_BLOCKBYTES] = {0};
 137
 138         memcpy(block, key, P->key_length);
 139         ossl_blake2s_update(c, block, BLAKE2S_BLOCKBYTES);
 140         OPENSSL_cleanse(block, BLAKE2S_BLOCKBYTES);
 141     }
 142
 143     return 1;
 144 }
 145
 146 /* Permute the state while xoring in the block of data. */
 147 static void blake2s_compress(BLAKE2S_CTX *S,
 148                             const uint8_t *blocks,
 149                             size_t len)
 150 {
 151     uint32_t m[16];
 152     uint32_t v[16];
 153     size_t i;
 154     size_t increment;
 155
 156     /*
 157      * There are two distinct usage vectors for this function:
 158      *
 159      * a) BLAKE2s_Update uses it to process complete blocks,
 160      *    possibly more than one at a time;
 161      *
 162      * b) BLAK2s_Final uses it to process last block, always
 163      *    single but possibly incomplete, in which case caller
 164      *    pads input with zeros.
 165      */
 166     assert(len < BLAKE2S_BLOCKBYTES || len % BLAKE2S_BLOCKBYTES == 0);
 167
 168     /*
 169      * Since last block is always processed with separate call,
 170      * |len| not being multiple of complete blocks can be observed
 171      * only with |len| being less than BLAKE2S_BLOCKBYTES ("less"
 172      * including even zero), which is why following assignment doesn't
 173      * have to reside inside the main loop below.
 174      */
 175     increment = len < BLAKE2S_BLOCKBYTES ? len : BLAKE2S_BLOCKBYTES;
 176
 177     for (i = 0; i < 8; ++i) {
 178         v[i] = S->h[i];
 179     }
 180
 181     do {
 182         for (i = 0; i < 16; ++i) {
 183             m[i] = load32(blocks + i * sizeof(m[i]));
 184         }
 185
 186         /* blake2s_increment_counter */
 187         S->t[0] += increment;
 188         S->t[1] += (S->t[0] < increment);
 189
 190         v[ 8] = blake2s_IV[0];
 191         v[ 9] = blake2s_IV[1];
 192         v[10] = blake2s_IV[2];
 193         v[11] = blake2s_IV[3];
 194         v[12] = S->t[0] ^ blake2s_IV[4];
 195         v[13] = S->t[1] ^ blake2s_IV[5];
 196         v[14] = S->f[0] ^ blake2s_IV[6];
 197         v[15] = S->f[1] ^ blake2s_IV[7];
 198 #define G(r,i,a,b,c,d) \
 199         do { \
 200             a = a + b + m[blake2s_sigma[r][2*i+0]]; \
 201             d = rotr32(d ^ a, 16); \
 202             c = c + d; \
 203             b = rotr32(b ^ c, 12); \
 204             a = a + b + m[blake2s_sigma[r][2*i+1]]; \
 205             d = rotr32(d ^ a, 8); \
 206             c = c + d; \
 207             b = rotr32(b ^ c, 7); \
 208         } while (0)
 209 #define ROUND(r)  \
 210         do { \
 211             G(r,0,v[ 0],v[ 4],v[ 8],v[12]); \
 212             G(r,1,v[ 1],v[ 5],v[ 9],v[13]); \
 213             G(r,2,v[ 2],v[ 6],v[10],v[14]); \
 214             G(r,3,v[ 3],v[ 7],v[11],v[15]); \
 215             G(r,4,v[ 0],v[ 5],v[10],v[15]); \
 216             G(r,5,v[ 1],v[ 6],v[11],v[12]); \
 217             G(r,6,v[ 2],v[ 7],v[ 8],v[13]); \
 218             G(r,7,v[ 3],v[ 4],v[ 9],v[14]); \
 219         } while (0)
 220 #if defined(OPENSSL_SMALL_FOOTPRINT)
 221         /* almost 3x reduction on x86_64, 4.5x on ARMv8, 4x on ARMv4 */
 222         for (i = 0; i < 10; i++) {
 223             ROUND(i);
 224         }
 225 #else
 226         ROUND(0);
 227         ROUND(1);
 228         ROUND(2);
 229         ROUND(3);
 230         ROUND(4);
 231         ROUND(5);
 232         ROUND(6);
 233         ROUND(7);
 234         ROUND(8);
 235         ROUND(9);
 236 #endif
 237
 238         for (i = 0; i < 8; ++i) {
 239             S->h[i] = v[i] ^= v[i + 8] ^ S->h[i];
 240         }
 241 #undef G
 242 #undef ROUND
 243         blocks += increment;
 244         len -= increment;
 245     } while (len);
 246 }
 247
 248 /* Absorb the input data into the hash state.  Always returns 1. */
 249 int ossl_blake2s_update(BLAKE2S_CTX *c, const void *data, size_t datalen)
 250 {
 251     const uint8_t *in = data;
 252     size_t fill;
 253
 254     /*
 255      * Intuitively one would expect intermediate buffer, c->buf, to
 256      * store incomplete blocks. But in this case we are interested to
 257      * temporarily stash even complete blocks, because last one in the
 258      * stream has to be treated in special way, and at this point we
 259      * don't know if last block in *this* call is last one "ever". This
 260      * is the reason for why |datalen| is compared as >, and not >=.
 261      */
 262     fill = sizeof(c->buf) - c->buflen;
 263     if (datalen > fill) {
 264         if (c->buflen) {
 265             memcpy(c->buf + c->buflen, in, fill); /* Fill buffer */
 266             blake2s_compress(c, c->buf, BLAKE2S_BLOCKBYTES);
 267             c->buflen = 0;
 268             in += fill;
 269             datalen -= fill;
 270         }
 271         if (datalen > BLAKE2S_BLOCKBYTES) {
 272             size_t stashlen = datalen % BLAKE2S_BLOCKBYTES;
 273             /*
 274              * If |datalen| is a multiple of the blocksize, stash
 275              * last complete block, it can be final one...
 276              */
 277             stashlen = stashlen ? stashlen : BLAKE2S_BLOCKBYTES;
 278             datalen -= stashlen;
 279             blake2s_compress(c, in, datalen);
 280             in += datalen;
 281             datalen = stashlen;
 282         }
 283     }
 284
 285     assert(datalen <= BLAKE2S_BLOCKBYTES);
 286
 287     memcpy(c->buf + c->buflen, in, datalen);
 288     c->buflen += datalen; /* Be lazy, do not compress */
 289
 290     return 1;
 291 }
 292
 293 /*
 294  * Calculate the final hash and save it in md.
 295  * Always returns 1.
 296  */
 297 int ossl_blake2s_final(unsigned char *md, BLAKE2S_CTX *c)
 298 {
 299     uint8_t outbuffer[BLAKE2S_OUTBYTES] = {0};
 300     uint8_t *target = outbuffer;
 301     int iter = (c->outlen + 3) / 4;
 302     int i;
 303
 304     /* Avoid writing to the temporary buffer if possible */
 305     if ((c->outlen % sizeof(c->h[0])) == 0)
 306         target = md;
 307
 308     blake2s_set_lastblock(c);
 309     /* Padding */
 310     memset(c->buf + c->buflen, 0, sizeof(c->buf) - c->buflen);
 311     blake2s_compress(c, c->buf, c->buflen);
 312
 313     /* Output full hash to buffer */
 314     for (i = 0; i < iter; ++i)
 315         store32(target + sizeof(c->h[i]) * i, c->h[i]);
 316
 317     if (target != md)
 318         memcpy(md, target, c->outlen);
 319
 320     OPENSSL_cleanse(c, sizeof(BLAKE2S_CTX));
 321     return 1;
 322 }