Split fe_set_b32 into reducing and normalizing variants

This commit is contained in:
Pieter Wuille
2023-02-05 17:19:00 -05:00
parent 006ddc1f42
commit 5b32602295
16 changed files with 69 additions and 40 deletions

View File

@@ -236,7 +236,7 @@ static int secp256k1_fe_impl_cmp_var(const secp256k1_fe *a, const secp256k1_fe *
return 0;
}
static int secp256k1_fe_impl_set_b32(secp256k1_fe *r, const unsigned char *a) {
static void secp256k1_fe_impl_set_b32_mod(secp256k1_fe *r, const unsigned char *a) {
r->n[0] = (uint64_t)a[31]
| ((uint64_t)a[30] << 8)
| ((uint64_t)a[29] << 16)
@@ -271,6 +271,10 @@ static int secp256k1_fe_impl_set_b32(secp256k1_fe *r, const unsigned char *a) {
| ((uint64_t)a[2] << 24)
| ((uint64_t)a[1] << 32)
| ((uint64_t)a[0] << 40);
}
static int secp256k1_fe_impl_set_b32_limit(secp256k1_fe *r, const unsigned char *a) {
secp256k1_fe_impl_set_b32_mod(r, a);
return !((r->n[4] == 0x0FFFFFFFFFFFFULL) & ((r->n[3] & r->n[2] & r->n[1]) == 0xFFFFFFFFFFFFFULL) & (r->n[0] >= 0xFFFFEFFFFFC2FULL));
}