634 lines
25 KiB
JavaScript
634 lines
25 KiB
JavaScript
"use strict";
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Object.defineProperty(exports, "__esModule", { value: true });
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exports.PrimeEdwardsPoint = void 0;
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exports.edwards = edwards;
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exports.eddsa = eddsa;
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exports.twistedEdwards = twistedEdwards;
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/**
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* Twisted Edwards curve. The formula is: ax² + y² = 1 + dx²y².
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* For design rationale of types / exports, see weierstrass module documentation.
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* Untwisted Edwards curves exist, but they aren't used in real-world protocols.
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* @module
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*/
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/*! noble-curves - MIT License (c) 2022 Paul Miller (paulmillr.com) */
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const utils_ts_1 = require("../utils.js");
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const curve_ts_1 = require("./curve.js");
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const modular_ts_1 = require("./modular.js");
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// Be friendly to bad ECMAScript parsers by not using bigint literals
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// prettier-ignore
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const _0n = BigInt(0), _1n = BigInt(1), _2n = BigInt(2), _8n = BigInt(8);
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function isEdValidXY(Fp, CURVE, x, y) {
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const x2 = Fp.sqr(x);
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const y2 = Fp.sqr(y);
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const left = Fp.add(Fp.mul(CURVE.a, x2), y2);
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const right = Fp.add(Fp.ONE, Fp.mul(CURVE.d, Fp.mul(x2, y2)));
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return Fp.eql(left, right);
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}
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function edwards(params, extraOpts = {}) {
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const validated = (0, curve_ts_1._createCurveFields)('edwards', params, extraOpts, extraOpts.FpFnLE);
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const { Fp, Fn } = validated;
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let CURVE = validated.CURVE;
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const { h: cofactor } = CURVE;
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(0, utils_ts_1._validateObject)(extraOpts, {}, { uvRatio: 'function' });
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// Important:
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// There are some places where Fp.BYTES is used instead of nByteLength.
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// So far, everything has been tested with curves of Fp.BYTES == nByteLength.
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// TODO: test and find curves which behave otherwise.
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const MASK = _2n << (BigInt(Fn.BYTES * 8) - _1n);
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const modP = (n) => Fp.create(n); // Function overrides
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// sqrt(u/v)
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const uvRatio = extraOpts.uvRatio ||
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((u, v) => {
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try {
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return { isValid: true, value: Fp.sqrt(Fp.div(u, v)) };
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}
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catch (e) {
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return { isValid: false, value: _0n };
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}
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});
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// Validate whether the passed curve params are valid.
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// equation ax² + y² = 1 + dx²y² should work for generator point.
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if (!isEdValidXY(Fp, CURVE, CURVE.Gx, CURVE.Gy))
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throw new Error('bad curve params: generator point');
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/**
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* Asserts coordinate is valid: 0 <= n < MASK.
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* Coordinates >= Fp.ORDER are allowed for zip215.
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*/
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function acoord(title, n, banZero = false) {
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const min = banZero ? _1n : _0n;
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(0, utils_ts_1.aInRange)('coordinate ' + title, n, min, MASK);
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return n;
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}
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function aextpoint(other) {
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if (!(other instanceof Point))
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throw new Error('ExtendedPoint expected');
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}
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// Converts Extended point to default (x, y) coordinates.
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// Can accept precomputed Z^-1 - for example, from invertBatch.
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const toAffineMemo = (0, utils_ts_1.memoized)((p, iz) => {
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const { X, Y, Z } = p;
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const is0 = p.is0();
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if (iz == null)
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iz = is0 ? _8n : Fp.inv(Z); // 8 was chosen arbitrarily
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const x = modP(X * iz);
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const y = modP(Y * iz);
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const zz = Fp.mul(Z, iz);
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if (is0)
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return { x: _0n, y: _1n };
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if (zz !== _1n)
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throw new Error('invZ was invalid');
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return { x, y };
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});
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const assertValidMemo = (0, utils_ts_1.memoized)((p) => {
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const { a, d } = CURVE;
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if (p.is0())
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throw new Error('bad point: ZERO'); // TODO: optimize, with vars below?
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// Equation in affine coordinates: ax² + y² = 1 + dx²y²
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// Equation in projective coordinates (X/Z, Y/Z, Z): (aX² + Y²)Z² = Z⁴ + dX²Y²
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const { X, Y, Z, T } = p;
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const X2 = modP(X * X); // X²
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const Y2 = modP(Y * Y); // Y²
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const Z2 = modP(Z * Z); // Z²
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const Z4 = modP(Z2 * Z2); // Z⁴
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const aX2 = modP(X2 * a); // aX²
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const left = modP(Z2 * modP(aX2 + Y2)); // (aX² + Y²)Z²
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const right = modP(Z4 + modP(d * modP(X2 * Y2))); // Z⁴ + dX²Y²
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if (left !== right)
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throw new Error('bad point: equation left != right (1)');
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// In Extended coordinates we also have T, which is x*y=T/Z: check X*Y == Z*T
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const XY = modP(X * Y);
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const ZT = modP(Z * T);
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if (XY !== ZT)
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throw new Error('bad point: equation left != right (2)');
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return true;
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});
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// Extended Point works in extended coordinates: (X, Y, Z, T) ∋ (x=X/Z, y=Y/Z, T=xy).
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// https://en.wikipedia.org/wiki/Twisted_Edwards_curve#Extended_coordinates
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class Point {
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constructor(X, Y, Z, T) {
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this.X = acoord('x', X);
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this.Y = acoord('y', Y);
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this.Z = acoord('z', Z, true);
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this.T = acoord('t', T);
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Object.freeze(this);
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}
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static CURVE() {
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return CURVE;
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}
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static fromAffine(p) {
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if (p instanceof Point)
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throw new Error('extended point not allowed');
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const { x, y } = p || {};
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acoord('x', x);
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acoord('y', y);
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return new Point(x, y, _1n, modP(x * y));
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}
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// Uses algo from RFC8032 5.1.3.
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static fromBytes(bytes, zip215 = false) {
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const len = Fp.BYTES;
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const { a, d } = CURVE;
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bytes = (0, utils_ts_1.copyBytes)((0, utils_ts_1._abytes2)(bytes, len, 'point'));
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(0, utils_ts_1._abool2)(zip215, 'zip215');
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const normed = (0, utils_ts_1.copyBytes)(bytes); // copy again, we'll manipulate it
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const lastByte = bytes[len - 1]; // select last byte
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normed[len - 1] = lastByte & ~0x80; // clear last bit
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const y = (0, utils_ts_1.bytesToNumberLE)(normed);
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// zip215=true is good for consensus-critical apps. =false follows RFC8032 / NIST186-5.
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// RFC8032 prohibits >= p, but ZIP215 doesn't
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// zip215=true: 0 <= y < MASK (2^256 for ed25519)
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// zip215=false: 0 <= y < P (2^255-19 for ed25519)
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const max = zip215 ? MASK : Fp.ORDER;
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(0, utils_ts_1.aInRange)('point.y', y, _0n, max);
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// Ed25519: x² = (y²-1)/(dy²+1) mod p. Ed448: x² = (y²-1)/(dy²-1) mod p. Generic case:
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// ax²+y²=1+dx²y² => y²-1=dx²y²-ax² => y²-1=x²(dy²-a) => x²=(y²-1)/(dy²-a)
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const y2 = modP(y * y); // denominator is always non-0 mod p.
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const u = modP(y2 - _1n); // u = y² - 1
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const v = modP(d * y2 - a); // v = d y² + 1.
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let { isValid, value: x } = uvRatio(u, v); // √(u/v)
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if (!isValid)
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throw new Error('bad point: invalid y coordinate');
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const isXOdd = (x & _1n) === _1n; // There are 2 square roots. Use x_0 bit to select proper
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const isLastByteOdd = (lastByte & 0x80) !== 0; // x_0, last bit
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if (!zip215 && x === _0n && isLastByteOdd)
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// if x=0 and x_0 = 1, fail
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throw new Error('bad point: x=0 and x_0=1');
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if (isLastByteOdd !== isXOdd)
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x = modP(-x); // if x_0 != x mod 2, set x = p-x
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return Point.fromAffine({ x, y });
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}
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static fromHex(bytes, zip215 = false) {
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return Point.fromBytes((0, utils_ts_1.ensureBytes)('point', bytes), zip215);
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}
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get x() {
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return this.toAffine().x;
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}
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get y() {
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return this.toAffine().y;
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}
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precompute(windowSize = 8, isLazy = true) {
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wnaf.createCache(this, windowSize);
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if (!isLazy)
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this.multiply(_2n); // random number
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return this;
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}
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// Useful in fromAffine() - not for fromBytes(), which always created valid points.
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assertValidity() {
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assertValidMemo(this);
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}
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// Compare one point to another.
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equals(other) {
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aextpoint(other);
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const { X: X1, Y: Y1, Z: Z1 } = this;
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const { X: X2, Y: Y2, Z: Z2 } = other;
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const X1Z2 = modP(X1 * Z2);
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const X2Z1 = modP(X2 * Z1);
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const Y1Z2 = modP(Y1 * Z2);
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const Y2Z1 = modP(Y2 * Z1);
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return X1Z2 === X2Z1 && Y1Z2 === Y2Z1;
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}
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is0() {
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return this.equals(Point.ZERO);
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}
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negate() {
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// Flips point sign to a negative one (-x, y in affine coords)
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return new Point(modP(-this.X), this.Y, this.Z, modP(-this.T));
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}
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// Fast algo for doubling Extended Point.
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// https://hyperelliptic.org/EFD/g1p/auto-twisted-extended.html#doubling-dbl-2008-hwcd
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// Cost: 4M + 4S + 1*a + 6add + 1*2.
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double() {
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const { a } = CURVE;
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const { X: X1, Y: Y1, Z: Z1 } = this;
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const A = modP(X1 * X1); // A = X12
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const B = modP(Y1 * Y1); // B = Y12
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const C = modP(_2n * modP(Z1 * Z1)); // C = 2*Z12
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const D = modP(a * A); // D = a*A
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const x1y1 = X1 + Y1;
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const E = modP(modP(x1y1 * x1y1) - A - B); // E = (X1+Y1)2-A-B
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const G = D + B; // G = D+B
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const F = G - C; // F = G-C
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const H = D - B; // H = D-B
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const X3 = modP(E * F); // X3 = E*F
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const Y3 = modP(G * H); // Y3 = G*H
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const T3 = modP(E * H); // T3 = E*H
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const Z3 = modP(F * G); // Z3 = F*G
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return new Point(X3, Y3, Z3, T3);
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}
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// Fast algo for adding 2 Extended Points.
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// https://hyperelliptic.org/EFD/g1p/auto-twisted-extended.html#addition-add-2008-hwcd
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// Cost: 9M + 1*a + 1*d + 7add.
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add(other) {
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aextpoint(other);
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const { a, d } = CURVE;
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const { X: X1, Y: Y1, Z: Z1, T: T1 } = this;
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const { X: X2, Y: Y2, Z: Z2, T: T2 } = other;
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const A = modP(X1 * X2); // A = X1*X2
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const B = modP(Y1 * Y2); // B = Y1*Y2
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const C = modP(T1 * d * T2); // C = T1*d*T2
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const D = modP(Z1 * Z2); // D = Z1*Z2
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const E = modP((X1 + Y1) * (X2 + Y2) - A - B); // E = (X1+Y1)*(X2+Y2)-A-B
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const F = D - C; // F = D-C
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const G = D + C; // G = D+C
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const H = modP(B - a * A); // H = B-a*A
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const X3 = modP(E * F); // X3 = E*F
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const Y3 = modP(G * H); // Y3 = G*H
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const T3 = modP(E * H); // T3 = E*H
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const Z3 = modP(F * G); // Z3 = F*G
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return new Point(X3, Y3, Z3, T3);
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}
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subtract(other) {
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return this.add(other.negate());
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}
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// Constant-time multiplication.
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multiply(scalar) {
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// 1 <= scalar < L
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if (!Fn.isValidNot0(scalar))
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throw new Error('invalid scalar: expected 1 <= sc < curve.n');
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const { p, f } = wnaf.cached(this, scalar, (p) => (0, curve_ts_1.normalizeZ)(Point, p));
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return (0, curve_ts_1.normalizeZ)(Point, [p, f])[0];
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}
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// Non-constant-time multiplication. Uses double-and-add algorithm.
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// It's faster, but should only be used when you don't care about
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// an exposed private key e.g. sig verification.
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// Does NOT allow scalars higher than CURVE.n.
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// Accepts optional accumulator to merge with multiply (important for sparse scalars)
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multiplyUnsafe(scalar, acc = Point.ZERO) {
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// 0 <= scalar < L
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if (!Fn.isValid(scalar))
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throw new Error('invalid scalar: expected 0 <= sc < curve.n');
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if (scalar === _0n)
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return Point.ZERO;
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if (this.is0() || scalar === _1n)
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return this;
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return wnaf.unsafe(this, scalar, (p) => (0, curve_ts_1.normalizeZ)(Point, p), acc);
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}
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// Checks if point is of small order.
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// If you add something to small order point, you will have "dirty"
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// point with torsion component.
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// Multiplies point by cofactor and checks if the result is 0.
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isSmallOrder() {
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return this.multiplyUnsafe(cofactor).is0();
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}
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// Multiplies point by curve order and checks if the result is 0.
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// Returns `false` is the point is dirty.
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isTorsionFree() {
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return wnaf.unsafe(this, CURVE.n).is0();
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}
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// Converts Extended point to default (x, y) coordinates.
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// Can accept precomputed Z^-1 - for example, from invertBatch.
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toAffine(invertedZ) {
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return toAffineMemo(this, invertedZ);
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}
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clearCofactor() {
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if (cofactor === _1n)
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return this;
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return this.multiplyUnsafe(cofactor);
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}
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toBytes() {
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const { x, y } = this.toAffine();
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// Fp.toBytes() allows non-canonical encoding of y (>= p).
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const bytes = Fp.toBytes(y);
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// Each y has 2 valid points: (x, y), (x,-y).
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// When compressing, it's enough to store y and use the last byte to encode sign of x
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bytes[bytes.length - 1] |= x & _1n ? 0x80 : 0;
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return bytes;
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}
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toHex() {
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return (0, utils_ts_1.bytesToHex)(this.toBytes());
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}
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toString() {
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return `<Point ${this.is0() ? 'ZERO' : this.toHex()}>`;
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}
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// TODO: remove
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get ex() {
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return this.X;
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}
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get ey() {
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return this.Y;
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}
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get ez() {
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return this.Z;
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}
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get et() {
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return this.T;
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}
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static normalizeZ(points) {
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return (0, curve_ts_1.normalizeZ)(Point, points);
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}
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static msm(points, scalars) {
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return (0, curve_ts_1.pippenger)(Point, Fn, points, scalars);
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}
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_setWindowSize(windowSize) {
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this.precompute(windowSize);
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}
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toRawBytes() {
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return this.toBytes();
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}
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}
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// base / generator point
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Point.BASE = new Point(CURVE.Gx, CURVE.Gy, _1n, modP(CURVE.Gx * CURVE.Gy));
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// zero / infinity / identity point
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Point.ZERO = new Point(_0n, _1n, _1n, _0n); // 0, 1, 1, 0
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// math field
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Point.Fp = Fp;
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// scalar field
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Point.Fn = Fn;
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const wnaf = new curve_ts_1.wNAF(Point, Fn.BITS);
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Point.BASE.precompute(8); // Enable precomputes. Slows down first publicKey computation by 20ms.
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return Point;
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}
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/**
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* Base class for prime-order points like Ristretto255 and Decaf448.
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* These points eliminate cofactor issues by representing equivalence classes
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* of Edwards curve points.
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*/
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class PrimeEdwardsPoint {
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constructor(ep) {
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this.ep = ep;
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}
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// Static methods that must be implemented by subclasses
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static fromBytes(_bytes) {
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(0, utils_ts_1.notImplemented)();
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}
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static fromHex(_hex) {
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(0, utils_ts_1.notImplemented)();
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}
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get x() {
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return this.toAffine().x;
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}
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get y() {
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return this.toAffine().y;
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}
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// Common implementations
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clearCofactor() {
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// no-op for prime-order groups
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return this;
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}
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assertValidity() {
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this.ep.assertValidity();
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}
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toAffine(invertedZ) {
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return this.ep.toAffine(invertedZ);
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}
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toHex() {
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return (0, utils_ts_1.bytesToHex)(this.toBytes());
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}
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toString() {
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return this.toHex();
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}
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isTorsionFree() {
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return true;
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}
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isSmallOrder() {
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return false;
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}
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add(other) {
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this.assertSame(other);
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return this.init(this.ep.add(other.ep));
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}
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subtract(other) {
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this.assertSame(other);
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return this.init(this.ep.subtract(other.ep));
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}
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multiply(scalar) {
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return this.init(this.ep.multiply(scalar));
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}
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multiplyUnsafe(scalar) {
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return this.init(this.ep.multiplyUnsafe(scalar));
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}
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double() {
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return this.init(this.ep.double());
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}
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negate() {
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return this.init(this.ep.negate());
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}
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precompute(windowSize, isLazy) {
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return this.init(this.ep.precompute(windowSize, isLazy));
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}
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/** @deprecated use `toBytes` */
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toRawBytes() {
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return this.toBytes();
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}
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}
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exports.PrimeEdwardsPoint = PrimeEdwardsPoint;
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/**
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* Initializes EdDSA signatures over given Edwards curve.
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*/
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function eddsa(Point, cHash, eddsaOpts = {}) {
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if (typeof cHash !== 'function')
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throw new Error('"hash" function param is required');
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(0, utils_ts_1._validateObject)(eddsaOpts, {}, {
|
|
adjustScalarBytes: 'function',
|
|
randomBytes: 'function',
|
|
domain: 'function',
|
|
prehash: 'function',
|
|
mapToCurve: 'function',
|
|
});
|
|
const { prehash } = eddsaOpts;
|
|
const { BASE, Fp, Fn } = Point;
|
|
const randomBytes = eddsaOpts.randomBytes || utils_ts_1.randomBytes;
|
|
const adjustScalarBytes = eddsaOpts.adjustScalarBytes || ((bytes) => bytes);
|
|
const domain = eddsaOpts.domain ||
|
|
((data, ctx, phflag) => {
|
|
(0, utils_ts_1._abool2)(phflag, 'phflag');
|
|
if (ctx.length || phflag)
|
|
throw new Error('Contexts/pre-hash are not supported');
|
|
return data;
|
|
}); // NOOP
|
|
// Little-endian SHA512 with modulo n
|
|
function modN_LE(hash) {
|
|
return Fn.create((0, utils_ts_1.bytesToNumberLE)(hash)); // Not Fn.fromBytes: it has length limit
|
|
}
|
|
// Get the hashed private scalar per RFC8032 5.1.5
|
|
function getPrivateScalar(key) {
|
|
const len = lengths.secretKey;
|
|
key = (0, utils_ts_1.ensureBytes)('private key', key, len);
|
|
// Hash private key with curve's hash function to produce uniformingly random input
|
|
// Check byte lengths: ensure(64, h(ensure(32, key)))
|
|
const hashed = (0, utils_ts_1.ensureBytes)('hashed private key', cHash(key), 2 * len);
|
|
const head = adjustScalarBytes(hashed.slice(0, len)); // clear first half bits, produce FE
|
|
const prefix = hashed.slice(len, 2 * len); // second half is called key prefix (5.1.6)
|
|
const scalar = modN_LE(head); // The actual private scalar
|
|
return { head, prefix, scalar };
|
|
}
|
|
/** Convenience method that creates public key from scalar. RFC8032 5.1.5 */
|
|
function getExtendedPublicKey(secretKey) {
|
|
const { head, prefix, scalar } = getPrivateScalar(secretKey);
|
|
const point = BASE.multiply(scalar); // Point on Edwards curve aka public key
|
|
const pointBytes = point.toBytes();
|
|
return { head, prefix, scalar, point, pointBytes };
|
|
}
|
|
/** Calculates EdDSA pub key. RFC8032 5.1.5. */
|
|
function getPublicKey(secretKey) {
|
|
return getExtendedPublicKey(secretKey).pointBytes;
|
|
}
|
|
// int('LE', SHA512(dom2(F, C) || msgs)) mod N
|
|
function hashDomainToScalar(context = Uint8Array.of(), ...msgs) {
|
|
const msg = (0, utils_ts_1.concatBytes)(...msgs);
|
|
return modN_LE(cHash(domain(msg, (0, utils_ts_1.ensureBytes)('context', context), !!prehash)));
|
|
}
|
|
/** Signs message with privateKey. RFC8032 5.1.6 */
|
|
function sign(msg, secretKey, options = {}) {
|
|
msg = (0, utils_ts_1.ensureBytes)('message', msg);
|
|
if (prehash)
|
|
msg = prehash(msg); // for ed25519ph etc.
|
|
const { prefix, scalar, pointBytes } = getExtendedPublicKey(secretKey);
|
|
const r = hashDomainToScalar(options.context, prefix, msg); // r = dom2(F, C) || prefix || PH(M)
|
|
const R = BASE.multiply(r).toBytes(); // R = rG
|
|
const k = hashDomainToScalar(options.context, R, pointBytes, msg); // R || A || PH(M)
|
|
const s = Fn.create(r + k * scalar); // S = (r + k * s) mod L
|
|
if (!Fn.isValid(s))
|
|
throw new Error('sign failed: invalid s'); // 0 <= s < L
|
|
const rs = (0, utils_ts_1.concatBytes)(R, Fn.toBytes(s));
|
|
return (0, utils_ts_1._abytes2)(rs, lengths.signature, 'result');
|
|
}
|
|
// verification rule is either zip215 or rfc8032 / nist186-5. Consult fromHex:
|
|
const verifyOpts = { zip215: true };
|
|
/**
|
|
* Verifies EdDSA signature against message and public key. RFC8032 5.1.7.
|
|
* An extended group equation is checked.
|
|
*/
|
|
function verify(sig, msg, publicKey, options = verifyOpts) {
|
|
const { context, zip215 } = options;
|
|
const len = lengths.signature;
|
|
sig = (0, utils_ts_1.ensureBytes)('signature', sig, len);
|
|
msg = (0, utils_ts_1.ensureBytes)('message', msg);
|
|
publicKey = (0, utils_ts_1.ensureBytes)('publicKey', publicKey, lengths.publicKey);
|
|
if (zip215 !== undefined)
|
|
(0, utils_ts_1._abool2)(zip215, 'zip215');
|
|
if (prehash)
|
|
msg = prehash(msg); // for ed25519ph, etc
|
|
const mid = len / 2;
|
|
const r = sig.subarray(0, mid);
|
|
const s = (0, utils_ts_1.bytesToNumberLE)(sig.subarray(mid, len));
|
|
let A, R, SB;
|
|
try {
|
|
// zip215=true is good for consensus-critical apps. =false follows RFC8032 / NIST186-5.
|
|
// zip215=true: 0 <= y < MASK (2^256 for ed25519)
|
|
// zip215=false: 0 <= y < P (2^255-19 for ed25519)
|
|
A = Point.fromBytes(publicKey, zip215);
|
|
R = Point.fromBytes(r, zip215);
|
|
SB = BASE.multiplyUnsafe(s); // 0 <= s < l is done inside
|
|
}
|
|
catch (error) {
|
|
return false;
|
|
}
|
|
if (!zip215 && A.isSmallOrder())
|
|
return false; // zip215 allows public keys of small order
|
|
const k = hashDomainToScalar(context, R.toBytes(), A.toBytes(), msg);
|
|
const RkA = R.add(A.multiplyUnsafe(k));
|
|
// Extended group equation
|
|
// [8][S]B = [8]R + [8][k]A'
|
|
return RkA.subtract(SB).clearCofactor().is0();
|
|
}
|
|
const _size = Fp.BYTES; // 32 for ed25519, 57 for ed448
|
|
const lengths = {
|
|
secretKey: _size,
|
|
publicKey: _size,
|
|
signature: 2 * _size,
|
|
seed: _size,
|
|
};
|
|
function randomSecretKey(seed = randomBytes(lengths.seed)) {
|
|
return (0, utils_ts_1._abytes2)(seed, lengths.seed, 'seed');
|
|
}
|
|
function keygen(seed) {
|
|
const secretKey = utils.randomSecretKey(seed);
|
|
return { secretKey, publicKey: getPublicKey(secretKey) };
|
|
}
|
|
function isValidSecretKey(key) {
|
|
return (0, utils_ts_1.isBytes)(key) && key.length === Fn.BYTES;
|
|
}
|
|
function isValidPublicKey(key, zip215) {
|
|
try {
|
|
return !!Point.fromBytes(key, zip215);
|
|
}
|
|
catch (error) {
|
|
return false;
|
|
}
|
|
}
|
|
const utils = {
|
|
getExtendedPublicKey,
|
|
randomSecretKey,
|
|
isValidSecretKey,
|
|
isValidPublicKey,
|
|
/**
|
|
* Converts ed public key to x public key. Uses formula:
|
|
* - ed25519:
|
|
* - `(u, v) = ((1+y)/(1-y), sqrt(-486664)*u/x)`
|
|
* - `(x, y) = (sqrt(-486664)*u/v, (u-1)/(u+1))`
|
|
* - ed448:
|
|
* - `(u, v) = ((y-1)/(y+1), sqrt(156324)*u/x)`
|
|
* - `(x, y) = (sqrt(156324)*u/v, (1+u)/(1-u))`
|
|
*/
|
|
toMontgomery(publicKey) {
|
|
const { y } = Point.fromBytes(publicKey);
|
|
const size = lengths.publicKey;
|
|
const is25519 = size === 32;
|
|
if (!is25519 && size !== 57)
|
|
throw new Error('only defined for 25519 and 448');
|
|
const u = is25519 ? Fp.div(_1n + y, _1n - y) : Fp.div(y - _1n, y + _1n);
|
|
return Fp.toBytes(u);
|
|
},
|
|
toMontgomerySecret(secretKey) {
|
|
const size = lengths.secretKey;
|
|
(0, utils_ts_1._abytes2)(secretKey, size);
|
|
const hashed = cHash(secretKey.subarray(0, size));
|
|
return adjustScalarBytes(hashed).subarray(0, size);
|
|
},
|
|
/** @deprecated */
|
|
randomPrivateKey: randomSecretKey,
|
|
/** @deprecated */
|
|
precompute(windowSize = 8, point = Point.BASE) {
|
|
return point.precompute(windowSize, false);
|
|
},
|
|
};
|
|
return Object.freeze({
|
|
keygen,
|
|
getPublicKey,
|
|
sign,
|
|
verify,
|
|
utils,
|
|
Point,
|
|
lengths,
|
|
});
|
|
}
|
|
function _eddsa_legacy_opts_to_new(c) {
|
|
const CURVE = {
|
|
a: c.a,
|
|
d: c.d,
|
|
p: c.Fp.ORDER,
|
|
n: c.n,
|
|
h: c.h,
|
|
Gx: c.Gx,
|
|
Gy: c.Gy,
|
|
};
|
|
const Fp = c.Fp;
|
|
const Fn = (0, modular_ts_1.Field)(CURVE.n, c.nBitLength, true);
|
|
const curveOpts = { Fp, Fn, uvRatio: c.uvRatio };
|
|
const eddsaOpts = {
|
|
randomBytes: c.randomBytes,
|
|
adjustScalarBytes: c.adjustScalarBytes,
|
|
domain: c.domain,
|
|
prehash: c.prehash,
|
|
mapToCurve: c.mapToCurve,
|
|
};
|
|
return { CURVE, curveOpts, hash: c.hash, eddsaOpts };
|
|
}
|
|
function _eddsa_new_output_to_legacy(c, eddsa) {
|
|
const Point = eddsa.Point;
|
|
const legacy = Object.assign({}, eddsa, {
|
|
ExtendedPoint: Point,
|
|
CURVE: c,
|
|
nBitLength: Point.Fn.BITS,
|
|
nByteLength: Point.Fn.BYTES,
|
|
});
|
|
return legacy;
|
|
}
|
|
// TODO: remove. Use eddsa
|
|
function twistedEdwards(c) {
|
|
const { CURVE, curveOpts, hash, eddsaOpts } = _eddsa_legacy_opts_to_new(c);
|
|
const Point = edwards(CURVE, curveOpts);
|
|
const EDDSA = eddsa(Point, hash, eddsaOpts);
|
|
return _eddsa_new_output_to_legacy(c, EDDSA);
|
|
}
|
|
//# sourceMappingURL=edwards.js.map
|