diff options
Diffstat (limited to 'src/group.h')
| -rw-r--r-- | src/group.h | 13 |
1 files changed, 6 insertions, 7 deletions
diff --git a/src/group.h b/src/group.h index 8e122ab429..863644f0f0 100644 --- a/src/group.h +++ b/src/group.h @@ -95,14 +95,13 @@ static int secp256k1_gej_is_infinity(const secp256k1_gej *a); /** Check whether a group element's y coordinate is a quadratic residue. */ static int secp256k1_gej_has_quad_y_var(const secp256k1_gej *a); -/** Set r equal to the double of a. If rzr is not-NULL, r->z = a->z * *rzr (where infinity means an implicit z = 0). - * a may not be zero. Constant time. */ -static void secp256k1_gej_double_nonzero(secp256k1_gej *r, const secp256k1_gej *a, secp256k1_fe *rzr); +/** Set r equal to the double of a, a cannot be infinity. Constant time. */ +static void secp256k1_gej_double_nonzero(secp256k1_gej *r, const secp256k1_gej *a); -/** Set r equal to the double of a. If rzr is not-NULL, r->z = a->z * *rzr (where infinity means an implicit z = 0). */ +/** Set r equal to the double of a. If rzr is not-NULL this sets *rzr such that r->z == a->z * *rzr (where infinity means an implicit z = 0). */ static void secp256k1_gej_double_var(secp256k1_gej *r, const secp256k1_gej *a, secp256k1_fe *rzr); -/** Set r equal to the sum of a and b. If rzr is non-NULL, r->z = a->z * *rzr (a cannot be infinity in that case). */ +/** Set r equal to the sum of a and b. If rzr is non-NULL this sets *rzr such that r->z == a->z * *rzr (a cannot be infinity in that case). */ static void secp256k1_gej_add_var(secp256k1_gej *r, const secp256k1_gej *a, const secp256k1_gej *b, secp256k1_fe *rzr); /** Set r equal to the sum of a and b (with b given in affine coordinates, and not infinity). */ @@ -110,7 +109,7 @@ static void secp256k1_gej_add_ge(secp256k1_gej *r, const secp256k1_gej *a, const /** Set r equal to the sum of a and b (with b given in affine coordinates). This is more efficient than secp256k1_gej_add_var. It is identical to secp256k1_gej_add_ge but without constant-time - guarantee, and b is allowed to be infinity. If rzr is non-NULL, r->z = a->z * *rzr (a cannot be infinity in that case). */ + guarantee, and b is allowed to be infinity. If rzr is non-NULL this sets *rzr such that r->z == a->z * *rzr (a cannot be infinity in that case). */ static void secp256k1_gej_add_ge_var(secp256k1_gej *r, const secp256k1_gej *a, const secp256k1_ge *b, secp256k1_fe *rzr); /** Set r equal to the sum of a and b (with the inverse of b's Z coordinate passed as bzinv). */ @@ -133,7 +132,7 @@ static void secp256k1_ge_to_storage(secp256k1_ge_storage *r, const secp256k1_ge /** Convert a group element back from the storage type. */ static void secp256k1_ge_from_storage(secp256k1_ge *r, const secp256k1_ge_storage *a); -/** If flag is true, set *r equal to *a; otherwise leave it. Constant-time. */ +/** If flag is true, set *r equal to *a; otherwise leave it. Constant-time. Both *r and *a must be initialized.*/ static void secp256k1_ge_storage_cmov(secp256k1_ge_storage *r, const secp256k1_ge_storage *a, int flag); /** Rescale a jacobian point by b which must be non-zero. Constant-time. */ |