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@okxweb3/crypto-lib

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A base package for @okxweb3/coin-*

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'use strict'; var BN = require('bn.js/lib/bn'); var inherits = require('inherits'); var Base = require('./base'); var utils = require('../utils'); function MontCurve(conf) { Base.call(this, 'mont', conf); this.a = new BN(conf.a, 16).toRed(this.red); this.b = new BN(conf.b, 16).toRed(this.red); this.i4 = new BN(4).toRed(this.red).redInvm(); this.two = new BN(2).toRed(this.red); this.a24 = this.i4.redMul(this.a.redAdd(this.two)); } inherits(MontCurve, Base); module.exports = MontCurve; MontCurve.prototype.validate = function validate(point) { var x = point.normalize().x; var x2 = x.redSqr(); var rhs = x2.redMul(x).redAdd(x2.redMul(this.a)).redAdd(x); var y = rhs.redSqrt(); return y.redSqr().cmp(rhs) === 0; }; function Point(curve, x, z) { Base.BasePoint.call(this, curve, 'projective'); if (x === null && z === null) { this.x = this.curve.one; this.z = this.curve.zero; } else { this.x = new BN(x, 16); this.z = new BN(z, 16); if (!this.x.red) this.x = this.x.toRed(this.curve.red); if (!this.z.red) this.z = this.z.toRed(this.curve.red); } } inherits(Point, Base.BasePoint); MontCurve.prototype.decodePoint = function decodePoint(bytes, enc) { return this.point(utils.toArray(bytes, enc), 1); }; MontCurve.prototype.point = function point(x, z) { return new Point(this, x, z); }; MontCurve.prototype.pointFromJSON = function pointFromJSON(obj) { return Point.fromJSON(this, obj); }; Point.prototype.precompute = function precompute() { }; Point.prototype._encode = function _encode() { return this.getX().toArray('be', this.curve.p.byteLength()); }; Point.fromJSON = function fromJSON(curve, obj) { return new Point(curve, obj[0], obj[1] || curve.one); }; Point.prototype.inspect = function inspect() { if (this.isInfinity()) return '<EC Point Infinity>'; return '<EC Point x: ' + this.x.fromRed().toString(16, 2) + ' z: ' + this.z.fromRed().toString(16, 2) + '>'; }; Point.prototype.isInfinity = function isInfinity() { return this.z.cmpn(0) === 0; }; Point.prototype.dbl = function dbl() { var a = this.x.redAdd(this.z); var aa = a.redSqr(); var b = this.x.redSub(this.z); var bb = b.redSqr(); var c = aa.redSub(bb); var nx = aa.redMul(bb); var nz = c.redMul(bb.redAdd(this.curve.a24.redMul(c))); return this.curve.point(nx, nz); }; Point.prototype.add = function add() { throw new Error('Not supported on Montgomery curve'); }; Point.prototype.diffAdd = function diffAdd(p, diff) { var a = this.x.redAdd(this.z); var b = this.x.redSub(this.z); var c = p.x.redAdd(p.z); var d = p.x.redSub(p.z); var da = d.redMul(a); var cb = c.redMul(b); var nx = diff.z.redMul(da.redAdd(cb).redSqr()); var nz = diff.x.redMul(da.redISub(cb).redSqr()); return this.curve.point(nx, nz); }; Point.prototype.mul = function mul(k) { var t = k.clone(); var a = this; var b = this.curve.point(null, null); var c = this; for (var bits = []; t.cmpn(0) !== 0; t.iushrn(1)) bits.push(t.andln(1)); for (var i = bits.length - 1; i >= 0; i--) { if (bits[i] === 0) { a = a.diffAdd(b, c); b = b.dbl(); } else { b = a.diffAdd(b, c); a = a.dbl(); } } return b; }; Point.prototype.mulAdd = function mulAdd() { throw new Error('Not supported on Montgomery curve'); }; Point.prototype.jumlAdd = function jumlAdd() { throw new Error('Not supported on Montgomery curve'); }; Point.prototype.eq = function eq(other) { return this.getX().cmp(other.getX()) === 0; }; Point.prototype.normalize = function normalize() { this.x = this.x.redMul(this.z.redInvm()); this.z = this.curve.one; return this; }; Point.prototype.getX = function getX() { this.normalize(); return this.x.fromRed(); }; //# sourceMappingURL=mont.js.map