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Hardcode numwords in semi-internal vli_numBits()

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This commit is contained in:
Manuel Pégourié-Gonnard
2019-11-04 12:56:59 +01:00
parent 94e48498ef
commit 2bf5a129cf
3 changed files with 10 additions and 13 deletions
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14
tinycrypt/ecc.c
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@@ -121,27 +121,25 @@ uECC_word_t uECC_vli_testBit(const uECC_word_t *vli, bitcount_t bit)
}
/* Counts the number of words in vli. */
static wordcount_t vli_numDigits(const uECC_word_t *vli,
const wordcount_t max_words)
static wordcount_t vli_numDigits(const uECC_word_t *vli)
{
wordcount_t i;
/* Search from the end until we find a non-zero digit. We do it in reverse
* because we expect that most digits will be nonzero. */
for (i = max_words - 1; i >= 0 && vli[i] == 0; --i) {
for (i = NUM_ECC_WORDS - 1; i >= 0 && vli[i] == 0; --i) {
}
return (i + 1);
}
bitcount_t uECC_vli_numBits(const uECC_word_t *vli,
const wordcount_t max_words)
bitcount_t uECC_vli_numBits(const uECC_word_t *vli)
{
uECC_word_t i;
uECC_word_t digit;
wordcount_t num_digits = vli_numDigits(vli, max_words);
wordcount_t num_digits = vli_numDigits(vli);
if (num_digits == 0) {
return 0;
}
@@ -461,7 +459,7 @@ void uECC_vli_mmod(uECC_word_t *result, uECC_word_t *product,
/* Shift mod so its highest set bit is at the maximum position. */
bitcount_t shift = (num_words * 2 * uECC_WORD_BITS) -
uECC_vli_numBits(mod, num_words);
uECC_vli_numBits(mod);
wordcount_t word_shift = shift / uECC_WORD_BITS;
wordcount_t bit_shift = shift % uECC_WORD_BITS;
uECC_word_t carry = 0;
@@ -1029,7 +1027,7 @@ int uECC_generate_random_int(uECC_word_t *random, const uECC_word_t *top,
{
uECC_word_t mask = (uECC_word_t)-1;
uECC_word_t tries;
bitcount_t num_bits = uECC_vli_numBits(top, num_words);
bitcount_t num_bits = uECC_vli_numBits(top);
if (!g_rng_function) {
return 0;