weak normalization

This commit is contained in:
Pieter Wuille
2014-12-10 14:34:25 +01:00
parent cf0c48bea5
commit 0295f0a33d
7 changed files with 65 additions and 17 deletions

View File

@@ -29,13 +29,7 @@ static int secp256k1_ge_is_infinity(const secp256k1_ge_t *a) {
static void secp256k1_ge_neg(secp256k1_ge_t *r, const secp256k1_ge_t *a) {
*r = *a;
secp256k1_fe_normalize(&r->y);
secp256k1_fe_negate(&r->y, &r->y, 1);
}
static void secp256k1_ge_neg_var(secp256k1_ge_t *r, const secp256k1_ge_t *a) {
*r = *a;
secp256k1_fe_normalize_var(&r->y);
secp256k1_fe_normalize_weak(&r->y);
secp256k1_fe_negate(&r->y, &r->y, 1);
}
@@ -172,12 +166,12 @@ static int secp256k1_gej_eq_x_var(const secp256k1_fe_t *x, const secp256k1_gej_t
return secp256k1_fe_equal(&r, &r2);
}
static void secp256k1_gej_neg_var(secp256k1_gej_t *r, const secp256k1_gej_t *a) {
static void secp256k1_gej_neg(secp256k1_gej_t *r, const secp256k1_gej_t *a) {
r->infinity = a->infinity;
r->x = a->x;
r->y = a->y;
r->z = a->z;
secp256k1_fe_normalize_var(&r->y);
secp256k1_fe_normalize_weak(&r->y);
secp256k1_fe_negate(&r->y, &r->y, 1);
}
@@ -359,9 +353,9 @@ static void secp256k1_gej_add_ge(secp256k1_gej_t *r, const secp256k1_gej_t *a, c
*/
secp256k1_fe_t zz; secp256k1_fe_sqr(&zz, &a->z); /* z = Z1^2 */
secp256k1_fe_t u1 = a->x; secp256k1_fe_normalize(&u1); /* u1 = U1 = X1*Z2^2 (1) */
secp256k1_fe_t u1 = a->x; secp256k1_fe_normalize_weak(&u1); /* u1 = U1 = X1*Z2^2 (1) */
secp256k1_fe_t u2; secp256k1_fe_mul(&u2, &b->x, &zz); /* u2 = U2 = X2*Z1^2 (1) */
secp256k1_fe_t s1 = a->y; secp256k1_fe_normalize(&s1); /* s1 = S1 = Y1*Z2^3 (1) */
secp256k1_fe_t s1 = a->y; secp256k1_fe_normalize_weak(&s1); /* s1 = S1 = Y1*Z2^3 (1) */
secp256k1_fe_t s2; secp256k1_fe_mul(&s2, &b->y, &zz); /* s2 = Y2*Z2^2 (1) */
secp256k1_fe_mul(&s2, &s2, &a->z); /* s2 = S2 = Y2*Z1^3 (1) */
secp256k1_fe_t z = a->z; /* z = Z = Z1*Z2 (8) */
@@ -388,7 +382,7 @@ static void secp256k1_gej_add_ge(secp256k1_gej_t *r, const secp256k1_gej_t *a, c
secp256k1_fe_mul(&t, &t, &rr); /* t = R*(2*R^2-3*Q) (1) */
secp256k1_fe_add(&t, &n); /* t = R*(2*R^2-3*Q)+M^4 (2) */
secp256k1_fe_negate(&r->y, &t, 2); /* r->y = R*(3*Q-2*R^2)-M^4 (3) */
secp256k1_fe_normalize(&r->y);
secp256k1_fe_normalize_weak(&r->y);
secp256k1_fe_mul_int(&r->x, 4 * (1 - a->infinity)); /* r->x = X3 = 4*(R^2-Q) */
secp256k1_fe_mul_int(&r->y, 4 * (1 - a->infinity)); /* r->y = Y3 = 4*R*(3*Q-2*R^2)-4*M^4 (4) */