Esempi in C++ (Cpp) per bignum_is_bit_set

Esempio n. 1

File: dh.c Progetto: ToThePradoHotel/libssh

ssh_string make_bignum_string(bignum num) {
  ssh_string ptr = NULL;
  int pad = 0;
  unsigned int len = bignum_num_bytes(num);
  unsigned int bits = bignum_num_bits(num);

  /* Remember if the fist bit is set, it is considered as a
   * negative number. So 0's must be appended */
  if (!(bits % 8) && bignum_is_bit_set(num, bits - 1)) {
    pad++;
  }

#ifdef DEBUG_CRYPTO
  fprintf(stderr, "%d bits, %d bytes, %d padding\n", bits, len, pad);
#endif /* DEBUG_CRYPTO */
/* TODO: fix that crap !! */
  ptr = malloc(4 + len + pad);
  if (ptr == NULL) {
    return NULL;
  }
  ptr->size = htonl(len + pad);
  if (pad) {
    ptr->string[0] = 0;
  }

#ifdef HAVE_LIBGCRYPT
  bignum_bn2bin(num, len, ptr->string + pad);
#elif HAVE_LIBCRYPTO
  bignum_bn2bin(num, ptr->string + pad);
#endif

  return ptr;
}

Esempio n. 2

File: bignum.c Progetto: simonsj/libssh

ssh_string ssh_make_bignum_string(bignum num) {
  ssh_string ptr = NULL;
  int pad = 0;
  unsigned int len = bignum_num_bytes(num);
  unsigned int bits = bignum_num_bits(num);

  if (len == 0) {
      return NULL;
  }

  /* If the first bit is set we have a negative number */
  if (!(bits % 8) && bignum_is_bit_set(num, bits - 1)) {
    pad++;
  }

#ifdef DEBUG_CRYPTO
  fprintf(stderr, "%d bits, %d bytes, %d padding\n", bits, len, pad);
#endif /* DEBUG_CRYPTO */

  ptr = ssh_string_new(len + pad);
  if (ptr == NULL) {
    return NULL;
  }

  /* We have a negative number so we need a leading zero */
  if (pad) {
    ptr->data[0] = 0;
  }

  bignum_bn2bin(num, len, ptr->data + pad);

  return ptr;
}