42 lines
1.8 KiB
JavaScript
42 lines
1.8 KiB
JavaScript
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/*! noble-curves - MIT License (c) 2022 Paul Miller (paulmillr.com) */
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import { sha256 } from '@noble/hashes/sha256';
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import { createCurve } from './_shortw_utils.js';
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import { createHasher } from './abstract/hash-to-curve.js';
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import { Field } from './abstract/modular.js';
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import { mapToCurveSimpleSWU } from './abstract/weierstrass.js';
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// NIST secp256r1 aka p256
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// https://www.secg.org/sec2-v2.pdf, https://neuromancer.sk/std/nist/P-256
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const Fp = Field(BigInt('0xffffffff00000001000000000000000000000000ffffffffffffffffffffffff'));
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const CURVE_A = Fp.create(BigInt('-3'));
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const CURVE_B = BigInt('0x5ac635d8aa3a93e7b3ebbd55769886bc651d06b0cc53b0f63bce3c3e27d2604b');
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// prettier-ignore
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export const p256 = createCurve({
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a: CURVE_A, // Equation params: a, b
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b: CURVE_B,
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Fp, // Field: 2n**224n * (2n**32n-1n) + 2n**192n + 2n**96n-1n
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// Curve order, total count of valid points in the field
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n: BigInt('0xffffffff00000000ffffffffffffffffbce6faada7179e84f3b9cac2fc632551'),
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// Base (generator) point (x, y)
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Gx: BigInt('0x6b17d1f2e12c4247f8bce6e563a440f277037d812deb33a0f4a13945d898c296'),
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Gy: BigInt('0x4fe342e2fe1a7f9b8ee7eb4a7c0f9e162bce33576b315ececbb6406837bf51f5'),
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h: BigInt(1),
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lowS: false,
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}, sha256);
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export const secp256r1 = p256;
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const mapSWU = /* @__PURE__ */ (() => mapToCurveSimpleSWU(Fp, {
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A: CURVE_A,
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B: CURVE_B,
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Z: Fp.create(BigInt('-10')),
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}))();
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const htf = /* @__PURE__ */ (() => createHasher(secp256r1.ProjectivePoint, (scalars) => mapSWU(scalars[0]), {
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DST: 'P256_XMD:SHA-256_SSWU_RO_',
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encodeDST: 'P256_XMD:SHA-256_SSWU_NU_',
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p: Fp.ORDER,
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m: 1,
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k: 128,
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expand: 'xmd',
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hash: sha256,
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}))();
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export const hashToCurve = /* @__PURE__ */ (() => htf.hashToCurve)();
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export const encodeToCurve = /* @__PURE__ */ (() => htf.encodeToCurve)();
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//# sourceMappingURL=p256.js.map
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