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smallstack reduction for wolfSSL_EC_POINT_get_affine_coordinates_GFp

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This commit is contained in:
Chris Conlon
2022-03-18 09:07:57 -06:00
parent 94e1b87ae0
commit ddc1899d48
1 changed files with 40 additions and 10 deletions
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50
src/ssl.c
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@ -40281,7 +40281,11 @@ int wolfSSL_EC_POINT_get_affine_coordinates_GFp(const WOLFSSL_EC_GROUP *group,
WOLFSSL_BN_CTX *ctx)
{
mp_digit mp;
mp_int modulus;
#ifdef WOLFSSL_SMALL_STACK
mp_int* modulus = NULL;
#else
mp_int modulus[1];
#endif
(void)ctx;
WOLFSSL_ENTER("wolfSSL_EC_POINT_get_affine_coordinates_GFp");
@ -40296,39 +40300,65 @@ int wolfSSL_EC_POINT_get_affine_coordinates_GFp(const WOLFSSL_EC_GROUP *group,
return WOLFSSL_FAILURE;
}
#ifdef WOLFSSL_SMALL_STACK
modulus = (mp_int*)XMALLOC(sizeof(mp_int), NULL, DYNAMIC_TYPE_BIGINT);
if (modulus == NULL) {
return WOLFSSL_FAILURE;
}
#endif
if (!wolfSSL_BN_is_one(point->Z)) {
if (mp_init(&modulus) != MP_OKAY) {
if (mp_init(modulus) != MP_OKAY) {
WOLFSSL_MSG("mp_init failed");
#ifdef WOLFSSL_SMALL_STACK
XFREE(modulus, NULL, DYNAMIC_TYPE_BIGINT);
#endif
return WOLFSSL_FAILURE;
}
/* Map the Jacobian point back to affine space */
if (mp_read_radix(&modulus, ecc_sets[group->curve_idx].prime, MP_RADIX_HEX) != MP_OKAY) {
if (mp_read_radix(modulus, ecc_sets[group->curve_idx].prime, MP_RADIX_HEX) != MP_OKAY) {
WOLFSSL_MSG("mp_read_radix failed");
mp_clear(&modulus);
mp_clear(modulus);
#ifdef WOLFSSL_SMALL_STACK
XFREE(modulus, NULL, DYNAMIC_TYPE_BIGINT);
#endif
return WOLFSSL_FAILURE;
}
if (mp_montgomery_setup(&modulus, &mp) != MP_OKAY) {
if (mp_montgomery_setup(modulus, &mp) != MP_OKAY) {
WOLFSSL_MSG("mp_montgomery_setup failed");
mp_clear(&modulus);
mp_clear(modulus);
#ifdef WOLFSSL_SMALL_STACK
XFREE(modulus, NULL, DYNAMIC_TYPE_BIGINT);
#endif
return WOLFSSL_FAILURE;
}
if (ecc_map((ecc_point*)point->internal, &modulus, mp) != MP_OKAY) {
if (ecc_map((ecc_point*)point->internal, modulus, mp) != MP_OKAY) {
WOLFSSL_MSG("ecc_map failed");
mp_clear(&modulus);
mp_clear(modulus);
#ifdef WOLFSSL_SMALL_STACK
XFREE(modulus, NULL, DYNAMIC_TYPE_BIGINT);
#endif
return WOLFSSL_FAILURE;
}
if (SetECPointExternal((WOLFSSL_EC_POINT *)point) != WOLFSSL_SUCCESS) {
WOLFSSL_MSG("SetECPointExternal failed");
mp_clear(&modulus);
mp_clear(modulus);
#ifdef WOLFSSL_SMALL_STACK
XFREE(modulus, NULL, DYNAMIC_TYPE_BIGINT);
#endif
return WOLFSSL_FAILURE;
}
mp_clear(&modulus);
mp_clear(modulus);
}
BN_copy(x, point->X);
BN_copy(y, point->Y);
#ifdef WOLFSSL_SMALL_STACK
XFREE(modulus, NULL, DYNAMIC_TYPE_BIGINT);
#endif
return WOLFSSL_SUCCESS;
}
#endif