ark_bn254/curves/
g1.rs

1use ark_ec::{
2    bn,
3    models::{short_weierstrass::SWCurveConfig, CurveConfig},
4    scalar_mul::glv::GLVConfig,
5    short_weierstrass::{Affine, Projective},
6};
7use ark_ff::{AdditiveGroup, BigInt, Field, MontFp, PrimeField, Zero};
8
9use crate::{Fq, Fr};
10
11#[derive(Clone, Default, PartialEq, Eq)]
12pub struct Config;
13
14pub type G1Affine = Affine<Config>;
15
16impl CurveConfig for Config {
17    type BaseField = Fq;
18    type ScalarField = Fr;
19
20    /// COFACTOR = 1
21    const COFACTOR: &'static [u64] = &[0x1];
22
23    /// COFACTOR_INV = COFACTOR^{-1} mod r = 1
24    const COFACTOR_INV: Fr = Fr::ONE;
25}
26
27impl SWCurveConfig for Config {
28    /// COEFF_A = 0
29    const COEFF_A: Fq = Fq::ZERO;
30
31    /// COEFF_B = 3
32    const COEFF_B: Fq = MontFp!("3");
33
34    /// AFFINE_GENERATOR_COEFFS = (G1_GENERATOR_X, G1_GENERATOR_Y)
35    const GENERATOR: G1Affine = G1Affine::new_unchecked(G1_GENERATOR_X, G1_GENERATOR_Y);
36
37    #[inline(always)]
38    fn mul_by_a(_: Self::BaseField) -> Self::BaseField {
39        Self::BaseField::zero()
40    }
41
42    #[inline]
43    fn mul_projective(
44        p: &bn::G1Projective<crate::Config>,
45        scalar: &[u64],
46    ) -> bn::G1Projective<crate::Config> {
47        let s = Self::ScalarField::from_sign_and_limbs(true, scalar);
48        GLVConfig::glv_mul_projective(*p, s)
49    }
50
51    #[inline]
52    fn is_in_correct_subgroup_assuming_on_curve(_p: &G1Affine) -> bool {
53        // G1 = E(Fq) so if the point is on the curve, it is also in the subgroup.
54        true
55    }
56}
57
58impl GLVConfig for Config {
59    const ENDO_COEFFS: &'static [Self::BaseField] = &[MontFp!(
60        "21888242871839275220042445260109153167277707414472061641714758635765020556616"
61    )];
62
63    const LAMBDA: Self::ScalarField =
64        MontFp!("21888242871839275217838484774961031246154997185409878258781734729429964517155");
65
66    const SCALAR_DECOMP_COEFFS: [(bool, <Self::ScalarField as PrimeField>::BigInt); 4] = [
67        (false, BigInt!("147946756881789319000765030803803410728")),
68        (true, BigInt!("9931322734385697763")),
69        (false, BigInt!("9931322734385697763")),
70        (false, BigInt!("147946756881789319010696353538189108491")),
71    ];
72
73    fn endomorphism(p: &Projective<Self>) -> Projective<Self> {
74        let mut res = (*p).clone();
75        res.x *= Self::ENDO_COEFFS[0];
76        res
77    }
78    fn endomorphism_affine(p: &Affine<Self>) -> Affine<Self> {
79        let mut res = (*p).clone();
80        res.x *= Self::ENDO_COEFFS[0];
81        res
82    }
83}
84
85/// G1_GENERATOR_X = 1
86pub const G1_GENERATOR_X: Fq = Fq::ONE;
87
88/// G1_GENERATOR_Y = 2
89pub const G1_GENERATOR_Y: Fq = MontFp!("2");
ark_bn254/curves/g1.rs

ark_bn254/curves/
g1.rs
