C++ (Cpp) util_ct_memcmp Examples

Example #1

File: util.c Project: cryptotronix/telehash-c

int util_cmp(char *a, char *b)
{
  if(!a || !b) return -1;
  if(a == b) return 0;
  if(strlen(a) != strlen(b)) return -1;
  return util_ct_memcmp(a,b,strlen(a));
}

Example #2

File: cs1a.c Project: alessiocamillo/telehash-c

lob_t ephemeral_decrypt(ephemeral_t ephem, lob_t outer)
{
  uint8_t iv[16], hmac[32];

  memset(iv,0,16);
  memcpy(iv,outer->body+16,4);

  memcpy(hmac,ephem->deckey,16);
  memcpy(hmac+16,iv,4);
  // mac just the ciphertext
  hmac_256(hmac,16+4,outer->body+16+4,outer->body_len-(4+16+4),hmac);
  fold3(hmac,hmac);

  if(util_ct_memcmp(hmac,outer->body+(outer->body_len-4),4) != 0) return LOG("hmac failed");

  // decrypt in place
  aes_128_ctr(ephem->deckey,outer->body_len-(16+4+4),iv,outer->body+16+4,outer->body+16+4);

  // return parse attempt
  return lob_parse(outer->body+16+4, outer->body_len-(16+4+4));
}

Example #3

File: cs1a.c Project: alessiocamillo/telehash-c

uint8_t remote_verify(remote_t remote, local_t local, lob_t outer)
{
  uint8_t shared[uECC_BYTES+4], hash[32];

  if(!remote || !local || !outer) return 1;
  if(outer->head_len != 1 || outer->head[0] != 0x1a) return 2;

  // generate the key for the hmac, combining the shared secret and IV
  if(!uECC_shared_secret(remote->key, local->secret, shared)) return 3;
  memcpy(shared+uECC_BYTES,outer->body+21,4);

  // verify
  hmac_256(shared,uECC_BYTES+4,outer->body,outer->body_len-4,hash);
  fold3(hash,hash);
  if(util_ct_memcmp(hash,outer->body+(outer->body_len-4),4) != 0)
  {
    LOG("hmac failed");
    return 4;
  }

  return 0;
}

Example #4

File: cs1c.c Project: mathias/telehash-c

uint8_t remote_validate(remote_t remote, lob_t args, lob_t sig, uint8_t *data, size_t len)
{
  uint8_t hash[32];
  if(!args || !sig || !data || !len) return 1;

  if(lob_get_cmp(args,"alg","HS256") == 0)
  {
    if(sig->body_len != 32 || !args->body_len) return 2;
    hmac_256(args->body,args->body_len,data,len,hash);
    return (util_ct_memcmp(sig->body,hash,32) == 0) ? 0 : 3;
  }

  if(lob_get_cmp(args,"alg","ES160") == 0)
  {
    if(!remote || sig->body_len != KEY_BYTES) return 2;
    // hash data first
    e3x_hash(data,len,hash);
    return (uECC_verify(remote->key, hash, 32, sig->body, curve) == 1) ? 0 : 3;
  }

  return 3;
}

Example #5

File: exchange.c Project: FitbeeCN/IoT_Library

// synchronize to incoming ephemeral key and set out at = in at, returns x if success, NULL if not
e3x_exchange_t e3x_exchange_sync(e3x_exchange_t x, lob_t outer)
{
  ephemeral_t ephem;
  if(!x || !outer) return LOG("bad args");
  if(outer->body_len < 16) return LOG("outer too small");

  if(x->in > x->out) x->out = x->in;

  // if the incoming ephemeral key is different, create a new ephemeral
  if(util_ct_memcmp(outer->body,x->eid,16) != 0)
  {
    ephem = x->cs->ephemeral_new(x->remote,outer);
    if(!ephem) return LOG("ephemeral creation failed %s",x->cs->err());
    x->cs->ephemeral_free(x->ephem);
    x->ephem = ephem;
    memcpy(x->eid,outer->body,16);
    // reset incoming channel id validation
    x->last = 0;
  }

  return x;
}