ark-curves-cherry-picked/bls12_377/src/curves/g2.rs
bls12_377/src/curves/g2.rsRaw
1use ark_ec::models::{ModelParameters, SWModelParameters};
2use ark_ff::{field_new, Zero};
3
4use crate::{fields::FQ_ZERO, g1, Fq, Fq2, Fr};
5
6#[derive(Clone, Default, PartialEq, Eq)]
7pub struct Parameters;
8
9impl ModelParameters for Parameters {
10 type BaseField = Fq2;
11 type ScalarField = Fr;
12
13 /// COFACTOR =
14 /// 7923214915284317143930293550643874566881017850177945424769256759165301436616933228209277966774092486467289478618404761412630691835764674559376407658497
15 #[rustfmt::skip]
16 const COFACTOR: &'static [u64] = &[
17 0x0000000000000001,
18 0x452217cc90000000,
19 0xa0f3622fba094800,
20 0xd693e8c36676bd09,
21 0x8c505634fae2e189,
22 0xfbb36b00e1dcc40c,
23 0xddd88d99a6f6a829,
24 0x26ba558ae9562a,
25 ];
26
27 /// COFACTOR_INV = COFACTOR^{-1} mod r
28 /// = 6764900296503390671038341982857278410319949526107311149686707033187604810669
29 #[rustfmt::skip]
30 const COFACTOR_INV: Fr = field_new!(Fr, "6764900296503390671038341982857278410319949526107311149686707033187604810669");
31}
32
33impl SWModelParameters for Parameters {
34 /// COEFF_A = [0, 0]
35 #[rustfmt::skip]
36 const COEFF_A: Fq2 = field_new!(Fq2,
37 g1::Parameters::COEFF_A,
38 g1::Parameters::COEFF_A,
39 );
40
41 // As per https://eprint.iacr.org/2012/072.pdf,
42 // this curve has b' = b/i, where b is the COEFF_B of G1, and x^6 -i is
43 // the irreducible poly used to extend from Fp2 to Fp12.
44 // In our case, i = u (App A.3, T_6).
45 /// COEFF_B = [0,
46 /// 155198655607781456406391640216936120121836107652948796323930557600032281009004493664981332883744016074664192874906]
47 #[rustfmt::skip]
48 const COEFF_B: Fq2 = field_new!(Fq2,
49 FQ_ZERO,
50 field_new!(Fq, "155198655607781456406391640216936120121836107652948796323930557600032281009004493664981332883744016074664192874906"),
51 );
52
53 /// AFFINE_GENERATOR_COEFFS = (G2_GENERATOR_X, G2_GENERATOR_Y)
54 const AFFINE_GENERATOR_COEFFS: (Self::BaseField, Self::BaseField) =
55 (G2_GENERATOR_X, G2_GENERATOR_Y);
56
57 #[inline(always)]
58 fn mul_by_a(_: &Self::BaseField) -> Self::BaseField {
59 Self::BaseField::zero()
60 }
61}
62
63#[rustfmt::skip]
64pub const G2_GENERATOR_X: Fq2 = field_new!(Fq2, G2_GENERATOR_X_C0, G2_GENERATOR_X_C1);
65#[rustfmt::skip]
66pub const G2_GENERATOR_Y: Fq2 = field_new!(Fq2, G2_GENERATOR_Y_C0, G2_GENERATOR_Y_C1);
67
68/// G2_GENERATOR_X_C0 =
69/// 233578398248691099356572568220835526895379068987715365179118596935057653620464273615301663571204657964920925606294
70#[rustfmt::skip]
71pub const G2_GENERATOR_X_C0: Fq = field_new!(Fq, "233578398248691099356572568220835526895379068987715365179118596935057653620464273615301663571204657964920925606294");
72
73/// G2_GENERATOR_X_C1 =
74/// 140913150380207355837477652521042157274541796891053068589147167627541651775299824604154852141315666357241556069118
75#[rustfmt::skip]
76pub const G2_GENERATOR_X_C1: Fq = field_new!(Fq, "140913150380207355837477652521042157274541796891053068589147167627541651775299824604154852141315666357241556069118");
77
78/// G2_GENERATOR_Y_C0 =
79/// 63160294768292073209381361943935198908131692476676907196754037919244929611450776219210369229519898517858833747423
80#[rustfmt::skip]
81pub const G2_GENERATOR_Y_C0: Fq = field_new!(Fq, "63160294768292073209381361943935198908131692476676907196754037919244929611450776219210369229519898517858833747423");
82
83/// G2_GENERATOR_Y_C1 =
84/// 149157405641012693445398062341192467754805999074082136895788947234480009303640899064710353187729182149407503257491
85#[rustfmt::skip]
86pub const G2_GENERATOR_Y_C1: Fq = field_new!(Fq, "149157405641012693445398062341192467754805999074082136895788947234480009303640899064710353187729182149407503257491");