ECC: handle zero in wc_ecc_mulmod()

Public API needs to handle multiplying by zero as the underlying code
doesn't and needn't.
This commit is contained in:
Sean Parkinson
2024-05-15 08:51:45 +10:00
parent 28bd4ebeea
commit 36754683d6
2 changed files with 25 additions and 0 deletions

View File

@@ -4058,6 +4058,12 @@ exit:
int wc_ecc_mulmod(const mp_int* k, ecc_point *G, ecc_point *R, mp_int* a,
mp_int* modulus, int map)
{
if ((k != NULL) && (G != NULL) && (mp_iszero(k))) {
mp_zero(G->x);
mp_zero(G->y);
mp_zero(G->z);
return MP_OKAY;
}
return wc_ecc_mulmod_ex(k, G, R, a, modulus, map, NULL);
}

View File

@@ -29328,6 +29328,9 @@ static wc_test_ret_t ecc_mulmod_test(ecc_key* key1)
ecc_key key2[1];
ecc_key key3[1];
#endif
#ifdef WOLFSSL_PUBLIC_MP
mp_int* priv;
#endif
#if defined(WOLFSSL_SMALL_STACK) && !defined(WOLFSSL_NO_MALLOC)
if ((key2 == NULL) || (key3 == NULL))
@@ -29362,6 +29365,22 @@ static wc_test_ret_t ecc_mulmod_test(ecc_key* key1)
goto done;
}
#ifdef WOLFSSL_PUBLIC_MP
priv = wc_ecc_key_get_priv(key1);
mp_zero(priv);
ret = wc_ecc_mulmod(wc_ecc_key_get_priv(key1), &key2->pubkey, &key3->pubkey,
wc_ecc_key_get_priv(key2), wc_ecc_key_get_priv(key3),
1);
if (ret != 0) {
ret = WC_TEST_RET_ENC_EC(ret);
goto done;
}
if (!wc_ecc_point_is_at_infinity(&key2->pubkey)) {
ret = WC_TEST_RET_ENC_EC(ret);
goto done;
}
#endif
done:
#if defined(WOLFSSL_SMALL_STACK) && !defined(WOLFSSL_NO_MALLOC)