blake2b.c

/*
   BLAKE2 reference source code package - reference C implementations

   Copyright 2012, Samuel Neves <sneves@dei.uc.pt>.  You may use this under the
   terms of the CC0, the OpenSSL Licence, or the Apache Public License 2.0, at
   your option.  The terms of these licenses can be found at:

   - CC0 1.0 Universal : http://creativecommons.org/publicdomain/zero/1.0
   - OpenSSL license   : https://www.openssl.org/source/license.html
   - Apache 2.0        : http://www.apache.org/licenses/LICENSE-2.0

   More information about the BLAKE2 hash function can be found at
   https://blake2.net.
*/

#include <string.h>

#include "blake2_common.h"
#include "blake2b.h"
#include "memzero.h"
#include "options.h"

typedef struct blake2b_param__ {
  uint8_t digest_length;                   /* 1 */
  uint8_t key_length;                      /* 2 */
  uint8_t fanout;                          /* 3 */
  uint8_t depth;                           /* 4 */
  uint32_t leaf_length;                    /* 8 */
  uint32_t node_offset;                    /* 12 */
  uint32_t xof_length;                     /* 16 */
  uint8_t node_depth;                      /* 17 */
  uint8_t inner_length;                    /* 18 */
  uint8_t reserved[14];                    /* 32 */
  uint8_t salt[BLAKE2B_SALTBYTES];         /* 48 */
  uint8_t personal[BLAKE2B_PERSONALBYTES]; /* 64 */
} __attribute__((packed)) blake2b_param;

static const uint64_t blake2b_IV[8] = {
    0x6a09e667f3bcc908ULL, 0xbb67ae8584caa73bULL, 0x3c6ef372fe94f82bULL,
    0xa54ff53a5f1d36f1ULL, 0x510e527fade682d1ULL, 0x9b05688c2b3e6c1fULL,
    0x1f83d9abfb41bd6bULL, 0x5be0cd19137e2179ULL};

static const uint8_t blake2b_sigma[12][16] = {
    {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15},
    {14, 10, 4, 8, 9, 15, 13, 6, 1, 12, 0, 2, 11, 7, 5, 3},
    {11, 8, 12, 0, 5, 2, 15, 13, 10, 14, 3, 6, 7, 1, 9, 4},
    {7, 9, 3, 1, 13, 12, 11, 14, 2, 6, 5, 10, 4, 0, 15, 8},
    {9, 0, 5, 7, 2, 4, 10, 15, 14, 1, 11, 12, 6, 8, 3, 13},
    {2, 12, 6, 10, 0, 11, 8, 3, 4, 13, 7, 5, 15, 14, 1, 9},
    {12, 5, 1, 15, 14, 13, 4, 10, 0, 7, 6, 3, 9, 2, 8, 11},
    {13, 11, 7, 14, 12, 1, 3, 9, 5, 0, 15, 4, 8, 6, 2, 10},
    {6, 15, 14, 9, 11, 3, 0, 8, 12, 2, 13, 7, 1, 4, 10, 5},
    {10, 2, 8, 4, 7, 6, 1, 5, 15, 11, 9, 14, 3, 12, 13, 0},
    {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15},
    {14, 10, 4, 8, 9, 15, 13, 6, 1, 12, 0, 2, 11, 7, 5, 3}};

static void blake2b_set_lastnode(blake2b_state *S) { S->f[1] = (uint64_t)-1; }

/* Some helper functions, not necessarily useful */
static int blake2b_is_lastblock(const blake2b_state *S) { return S->f[0] != 0; }

static void blake2b_set_lastblock(blake2b_state *S) {
  if (S->last_node) blake2b_set_lastnode(S);

  S->f[0] = (uint64_t)-1;
}

static void blake2b_increment_counter(blake2b_state *S, const uint64_t inc) {
  S->t[0] += inc;
  S->t[1] += (S->t[0] < inc);
}

static void blake2b_init0(blake2b_state *S) {
  size_t i = 0;
  memzero(S, sizeof(blake2b_state));

  for (i = 0; i < 8; ++i) S->h[i] = blake2b_IV[i];
}

/* init xors IV with input parameter block */
int blake2b_init_param(blake2b_state *S, const blake2b_param *P) {
  const uint8_t *p = (const uint8_t *)(P);
  size_t i = 0;

  blake2b_init0(S);

  /* IV XOR ParamBlock */
  for (i = 0; i < 8; ++i) S->h[i] ^= load64(p + sizeof(S->h[i]) * i);

  S->outlen = P->digest_length;
  return 0;
}

/* Sequential blake2b initialization */
int blake2b_Init(blake2b_state *S, size_t outlen) {
  blake2b_param P[1] = {0};

  if ((!outlen) || (outlen > BLAKE2B_OUTBYTES)) return -1;

  P->digest_length = (uint8_t)outlen;
  P->key_length = 0;
  P->fanout = 1;
  P->depth = 1;
  store32(&P->leaf_length, 0);
  store32(&P->node_offset, 0);
  store32(&P->xof_length, 0);
  P->node_depth = 0;
  P->inner_length = 0;
  memzero(P->reserved, sizeof(P->reserved));
  memzero(P->salt, sizeof(P->salt));
  memzero(P->personal, sizeof(P->personal));
  return blake2b_init_param(S, P);
}

int blake2b_InitPersonal(blake2b_state *S, size_t outlen, const void *personal,
                         size_t personal_len) {
  blake2b_param P[1] = {0};

  if ((!outlen) || (outlen > BLAKE2B_OUTBYTES)) return -1;
  if ((!personal) || (personal_len != BLAKE2B_PERSONALBYTES)) return -1;

  P->digest_length = (uint8_t)outlen;
  P->key_length = 0;
  P->fanout = 1;
  P->depth = 1;
  store32(&P->leaf_length, 0);
  store32(&P->node_offset, 0);
  store32(&P->xof_length, 0);
  P->node_depth = 0;
  P->inner_length = 0;
  memzero(P->reserved, sizeof(P->reserved));
  memzero(P->salt, sizeof(P->salt));
  memcpy(P->personal, personal, BLAKE2B_PERSONALBYTES);
  return blake2b_init_param(S, P);
}

int blake2b_InitKey(blake2b_state *S, size_t outlen, const void *key,
                    size_t keylen) {
  blake2b_param P[1] = {0};

  if ((!outlen) || (outlen > BLAKE2B_OUTBYTES)) return -1;

  if (!key || !keylen || keylen > BLAKE2B_KEYBYTES) return -1;

  P->digest_length = (uint8_t)outlen;
  P->key_length = (uint8_t)keylen;
  P->fanout = 1;
  P->depth = 1;
  store32(&P->leaf_length, 0);
  store32(&P->node_offset, 0);
  store32(&P->xof_length, 0);
  P->node_depth = 0;
  P->inner_length = 0;
  memzero(P->reserved, sizeof(P->reserved));
  memzero(P->salt, sizeof(P->salt));
  memzero(P->personal, sizeof(P->personal));

  if (blake2b_init_param(S, P) < 0) return -1;

  {
    uint8_t block[BLAKE2B_BLOCKBYTES] = {0};
    memzero(block, BLAKE2B_BLOCKBYTES);
    memcpy(block, key, keylen);
    blake2b_Update(S, block, BLAKE2B_BLOCKBYTES);
    memzero(block, BLAKE2B_BLOCKBYTES); /* Burn the key from stack */
  }
  return 0;
}

#define G(m, r, i, a, b, c, d)                           \
  do {                                                   \
    *(a) = *(a) + *(b) + m[blake2b_sigma[r][2 * i + 0]]; \
    *(d) = rotr64(*(d) ^ *(a), 32);                      \
    *(c) = *(c) + *(d);                                  \
    *(b) = rotr64(*(b) ^ *(c), 24);                      \
    *(a) = *(a) + *(b) + m[blake2b_sigma[r][2 * i + 1]]; \
    *(d) = rotr64(*(d) ^ *(a), 16);                      \
    *(c) = *(c) + *(d);                                  \
    *(b) = rotr64(*(b) ^ *(c), 63);                      \
  } while (0)

#if OPTIMIZE_SIZE_BLAKE2B
static void g(uint64_t *m, int r, int i, uint64_t *a, uint64_t *b, uint64_t *c,
              uint64_t *d) {
  G(m, r, i, a, b, c, d);
}
#else
#define g(m, r, i, a, b, c, d) G(m, r, i, a, b, c, d)
#endif

#define ROUND(m, v, r)                        \
  do {                                        \
    g(m, r, 0, v + 0, v + 4, v + 8, v + 12);  \
    g(m, r, 1, v + 1, v + 5, v + 9, v + 13);  \
    g(m, r, 2, v + 2, v + 6, v + 10, v + 14); \
    g(m, r, 3, v + 3, v + 7, v + 11, v + 15); \
    g(m, r, 4, v + 0, v + 5, v + 10, v + 15); \
    g(m, r, 5, v + 1, v + 6, v + 11, v + 12); \
    g(m, r, 6, v + 2, v + 7, v + 8, v + 13);  \
    g(m, r, 7, v + 3, v + 4, v + 9, v + 14);  \
  } while (0)

static void blake2b_compress(blake2b_state *S,
                             const uint8_t block[BLAKE2B_BLOCKBYTES]) {
  uint64_t m[16] = {0};
  uint64_t v[16] = {0};
  size_t i = 0;

  for (i = 0; i < 16; ++i) {
    m[i] = load64(block + i * sizeof(m[i]));
  }

  for (i = 0; i < 8; ++i) {
    v[i] = S->h[i];
  }

  v[8] = blake2b_IV[0];
  v[9] = blake2b_IV[1];
  v[10] = blake2b_IV[2];
  v[11] = blake2b_IV[3];
  v[12] = blake2b_IV[4] ^ S->t[0];
  v[13] = blake2b_IV[5] ^ S->t[1];
  v[14] = blake2b_IV[6] ^ S->f[0];
  v[15] = blake2b_IV[7] ^ S->f[1];

#if OPTIMIZE_SIZE_BLAKE2B
  for (int r = 0; r < 12; r++) {
    ROUND(m, v, r);
  }
#else
  ROUND(m, v, 0);
  ROUND(m, v, 1);
  ROUND(m, v, 2);
  ROUND(m, v, 3);
  ROUND(m, v, 4);
  ROUND(m, v, 5);
  ROUND(m, v, 6);
  ROUND(m, v, 7);
  ROUND(m, v, 8);
  ROUND(m, v, 9);
  ROUND(m, v, 10);
  ROUND(m, v, 11);
#endif

  for (i = 0; i < 8; ++i) {
    S->h[i] = S->h[i] ^ v[i] ^ v[i + 8];
  }
}

#undef G
#undef ROUND

int blake2b_Update(blake2b_state *S, const void *pin, size_t inlen) {
  const unsigned char *in = (const unsigned char *)pin;
  if (inlen > 0) {
    size_t left = S->buflen;
    size_t fill = BLAKE2B_BLOCKBYTES - left;
    if (inlen > fill) {
      S->buflen = 0;
      memcpy(S->buf + left, in, fill); /* Fill buffer */
      blake2b_increment_counter(S, BLAKE2B_BLOCKBYTES);
      blake2b_compress(S, S->buf); /* Compress */
      in += fill;
      inlen -= fill;
      while (inlen > BLAKE2B_BLOCKBYTES) {
        blake2b_increment_counter(S, BLAKE2B_BLOCKBYTES);
        blake2b_compress(S, in);
        in += BLAKE2B_BLOCKBYTES;
        inlen -= BLAKE2B_BLOCKBYTES;
      }
    }
    memcpy(S->buf + S->buflen, in, inlen);
    S->buflen += inlen;
  }
  return 0;
}

int blake2b_Final(blake2b_state *S, void *out, size_t outlen) {
  uint8_t buffer[BLAKE2B_OUTBYTES] = {0};
  size_t i = 0;

  if (out == NULL || outlen < S->outlen) return -1;

  if (blake2b_is_lastblock(S)) return -1;

  blake2b_increment_counter(S, S->buflen);
  blake2b_set_lastblock(S);
  memzero(S->buf + S->buflen, BLAKE2B_BLOCKBYTES - S->buflen); /* Padding */
  blake2b_compress(S, S->buf);

  for (i = 0; i < 8; ++i) /* Output full hash to temp buffer */
    store64(buffer + sizeof(S->h[i]) * i, S->h[i]);

  memcpy(out, buffer, S->outlen);
  memzero(buffer, sizeof(buffer));
  return 0;
}

int blake2b(const uint8_t *msg, uint32_t msg_len, void *out, size_t outlen) {
  BLAKE2B_CTX ctx;
  if (0 != blake2b_Init(&ctx, outlen)) return -1;
  if (0 != blake2b_Update(&ctx, msg, msg_len)) return -1;
  if (0 != blake2b_Final(&ctx, out, outlen)) return -1;
  return 0;
}

int blake2b_Key(const uint8_t *msg, uint32_t msg_len, const void *key,
                size_t keylen, void *out, size_t outlen) {
  BLAKE2B_CTX ctx;
  if (0 != blake2b_InitKey(&ctx, outlen, key, keylen)) return -1;
  if (0 != blake2b_Update(&ctx, msg, msg_len)) return -1;
  if (0 != blake2b_Final(&ctx, out, outlen)) return -1;
  return 0;
}