noble-curves/src/p384.ts

54 lines
1.9 KiB
TypeScript

/*! noble-curves - MIT License (c) 2022 Paul Miller (paulmillr.com) */
import { createCurve } from './_shortw_utils.js';
import { sha384 } from '@noble/hashes/sha512';
import { Field } from './abstract/modular.js';
import { mapToCurveSimpleSWU } from './abstract/weierstrass.js';
import * as htf from './abstract/hash-to-curve.js';
// NIST secp384r1 aka p384
// https://www.secg.org/sec2-v2.pdf, https://neuromancer.sk/std/nist/P-384
// Field over which we'll do calculations.
// prettier-ignore
const P = BigInt('0xfffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffeffffffff0000000000000000ffffffff');
const Fp = Field(P);
const CURVE_A = Fp.create(BigInt('-3'));
// prettier-ignore
const CURVE_B = BigInt('0xb3312fa7e23ee7e4988e056be3f82d19181d9c6efe8141120314088f5013875ac656398d8a2ed19d2a85c8edd3ec2aef');
// prettier-ignore
export const p384 = createCurve({
a: CURVE_A, // Equation params: a, b
b: CURVE_B,
Fp, // Field: 2n**384n - 2n**128n - 2n**96n + 2n**32n - 1n
// Curve order, total count of valid points in the field.
n: BigInt('0xffffffffffffffffffffffffffffffffffffffffffffffffc7634d81f4372ddf581a0db248b0a77aecec196accc52973'),
// Base (generator) point (x, y)
Gx: BigInt('0xaa87ca22be8b05378eb1c71ef320ad746e1d3b628ba79b9859f741e082542a385502f25dbf55296c3a545e3872760ab7'),
Gy: BigInt('0x3617de4a96262c6f5d9e98bf9292dc29f8f41dbd289a147ce9da3113b5f0b8c00a60b1ce1d7e819d7a431d7c90ea0e5f'),
h: BigInt(1),
lowS: false,
} as const, sha384);
export const secp384r1 = p384;
const mapSWU = mapToCurveSimpleSWU(Fp, {
A: CURVE_A,
B: CURVE_B,
Z: Fp.create(BigInt('-12')),
});
const { hashToCurve, encodeToCurve } = htf.createHasher(
secp384r1.ProjectivePoint,
(scalars: bigint[]) => mapSWU(scalars[0]),
{
DST: 'P384_XMD:SHA-384_SSWU_RO_',
encodeDST: 'P384_XMD:SHA-384_SSWU_NU_',
p: Fp.ORDER,
m: 1,
k: 192,
expand: 'xmd',
hash: sha384,
}
);
export { hashToCurve, encodeToCurve };