PHP WebShell
Текущая директория: /usr/lib/node_modules/bitgo/node_modules/@noble/curves/abstract
Просмотр файла: curve.js
"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.wNAF = void 0;
exports.negateCt = negateCt;
exports.normalizeZ = normalizeZ;
exports.mulEndoUnsafe = mulEndoUnsafe;
exports.pippenger = pippenger;
exports.precomputeMSMUnsafe = precomputeMSMUnsafe;
exports.validateBasic = validateBasic;
exports._createCurveFields = _createCurveFields;
/**
* Methods for elliptic curve multiplication by scalars.
* Contains wNAF, pippenger.
* @module
*/
/*! noble-curves - MIT License (c) 2022 Paul Miller (paulmillr.com) */
const utils_ts_1 = require("../utils.js");
const modular_ts_1 = require("./modular.js");
const _0n = BigInt(0);
const _1n = BigInt(1);
function negateCt(condition, item) {
const neg = item.negate();
return condition ? neg : item;
}
/**
* Takes a bunch of Projective Points but executes only one
* inversion on all of them. Inversion is very slow operation,
* so this improves performance massively.
* Optimization: converts a list of projective points to a list of identical points with Z=1.
*/
function normalizeZ(c, points) {
const invertedZs = (0, modular_ts_1.FpInvertBatch)(c.Fp, points.map((p) => p.Z));
return points.map((p, i) => c.fromAffine(p.toAffine(invertedZs[i])));
}
function validateW(W, bits) {
if (!Number.isSafeInteger(W) || W <= 0 || W > bits)
throw new Error('invalid window size, expected [1..' + bits + '], got W=' + W);
}
function calcWOpts(W, scalarBits) {
validateW(W, scalarBits);
const windows = Math.ceil(scalarBits / W) + 1; // W=8 33. Not 32, because we skip zero
const windowSize = 2 ** (W - 1); // W=8 128. Not 256, because we skip zero
const maxNumber = 2 ** W; // W=8 256
const mask = (0, utils_ts_1.bitMask)(W); // W=8 255 == mask 0b11111111
const shiftBy = BigInt(W); // W=8 8
return { windows, windowSize, mask, maxNumber, shiftBy };
}
function calcOffsets(n, window, wOpts) {
const { windowSize, mask, maxNumber, shiftBy } = wOpts;
let wbits = Number(n & mask); // extract W bits.
let nextN = n >> shiftBy; // shift number by W bits.
// What actually happens here:
// const highestBit = Number(mask ^ (mask >> 1n));
// let wbits2 = wbits - 1; // skip zero
// if (wbits2 & highestBit) { wbits2 ^= Number(mask); // (~);
// split if bits > max: +224 => 256-32
if (wbits > windowSize) {
// we skip zero, which means instead of `>= size-1`, we do `> size`
wbits -= maxNumber; // -32, can be maxNumber - wbits, but then we need to set isNeg here.
nextN += _1n; // +256 (carry)
}
const offsetStart = window * windowSize;
const offset = offsetStart + Math.abs(wbits) - 1; // -1 because we skip zero
const isZero = wbits === 0; // is current window slice a 0?
const isNeg = wbits < 0; // is current window slice negative?
const isNegF = window % 2 !== 0; // fake random statement for noise
const offsetF = offsetStart; // fake offset for noise
return { nextN, offset, isZero, isNeg, isNegF, offsetF };
}
function validateMSMPoints(points, c) {
if (!Array.isArray(points))
throw new Error('array expected');
points.forEach((p, i) => {
if (!(p instanceof c))
throw new Error('invalid point at index ' + i);
});
}
function validateMSMScalars(scalars, field) {
if (!Array.isArray(scalars))
throw new Error('array of scalars expected');
scalars.forEach((s, i) => {
if (!field.isValid(s))
throw new Error('invalid scalar at index ' + i);
});
}
// Since points in different groups cannot be equal (different object constructor),
// we can have single place to store precomputes.
// Allows to make points frozen / immutable.
const pointPrecomputes = new WeakMap();
const pointWindowSizes = new WeakMap();
function getW(P) {
// To disable precomputes:
// return 1;
return pointWindowSizes.get(P) || 1;
}
function assert0(n) {
if (n !== _0n)
throw new Error('invalid wNAF');
}
/**
* Elliptic curve multiplication of Point by scalar. Fragile.
* Table generation takes **30MB of ram and 10ms on high-end CPU**,
* but may take much longer on slow devices. Actual generation will happen on
* first call of `multiply()`. By default, `BASE` point is precomputed.
*
* Scalars should always be less than curve order: this should be checked inside of a curve itself.
* Creates precomputation tables for fast multiplication:
* - private scalar is split by fixed size windows of W bits
* - every window point is collected from window's table & added to accumulator
* - since windows are different, same point inside tables won't be accessed more than once per calc
* - each multiplication is 'Math.ceil(CURVE_ORDER / 𝑊) + 1' point additions (fixed for any scalar)
* - +1 window is neccessary for wNAF
* - wNAF reduces table size: 2x less memory + 2x faster generation, but 10% slower multiplication
*
* @todo Research returning 2d JS array of windows, instead of a single window.
* This would allow windows to be in different memory locations
*/
class wNAF {
// Parametrized with a given Point class (not individual point)
constructor(Point, bits) {
this.BASE = Point.BASE;
this.ZERO = Point.ZERO;
this.Fn = Point.Fn;
this.bits = bits;
}
// non-const time multiplication ladder
_unsafeLadder(elm, n, p = this.ZERO) {
let d = elm;
while (n > _0n) {
if (n & _1n)
p = p.add(d);
d = d.double();
n >>= _1n;
}
return p;
}
/**
* Creates a wNAF precomputation window. Used for caching.
* Default window size is set by `utils.precompute()` and is equal to 8.
* Number of precomputed points depends on the curve size:
* 2^(𝑊−1) * (Math.ceil(𝑛 / 𝑊) + 1), where:
* - 𝑊 is the window size
* - 𝑛 is the bitlength of the curve order.
* For a 256-bit curve and window size 8, the number of precomputed points is 128 * 33 = 4224.
* @param point Point instance
* @param W window size
* @returns precomputed point tables flattened to a single array
*/
precomputeWindow(point, W) {
const { windows, windowSize } = calcWOpts(W, this.bits);
const points = [];
let p = point;
let base = p;
for (let window = 0; window < windows; window++) {
base = p;
points.push(base);
// i=1, bc we skip 0
for (let i = 1; i < windowSize; i++) {
base = base.add(p);
points.push(base);
}
p = base.double();
}
return points;
}
/**
* Implements ec multiplication using precomputed tables and w-ary non-adjacent form.
* More compact implementation:
* https://github.com/paulmillr/noble-secp256k1/blob/47cb1669b6e506ad66b35fe7d76132ae97465da2/index.ts#L502-L541
* @returns real and fake (for const-time) points
*/
wNAF(W, precomputes, n) {
// Scalar should be smaller than field order
if (!this.Fn.isValid(n))
throw new Error('invalid scalar');
// Accumulators
let p = this.ZERO;
let f = this.BASE;
// This code was first written with assumption that 'f' and 'p' will never be infinity point:
// since each addition is multiplied by 2 ** W, it cannot cancel each other. However,
// there is negate now: it is possible that negated element from low value
// would be the same as high element, which will create carry into next window.
// It's not obvious how this can fail, but still worth investigating later.
const wo = calcWOpts(W, this.bits);
for (let window = 0; window < wo.windows; window++) {
// (n === _0n) is handled and not early-exited. isEven and offsetF are used for noise
const { nextN, offset, isZero, isNeg, isNegF, offsetF } = calcOffsets(n, window, wo);
n = nextN;
if (isZero) {
// bits are 0: add garbage to fake point
// Important part for const-time getPublicKey: add random "noise" point to f.
f = f.add(negateCt(isNegF, precomputes[offsetF]));
}
else {
// bits are 1: add to result point
p = p.add(negateCt(isNeg, precomputes[offset]));
}
}
assert0(n);
// Return both real and fake points: JIT won't eliminate f.
// At this point there is a way to F be infinity-point even if p is not,
// which makes it less const-time: around 1 bigint multiply.
return { p, f };
}
/**
* Implements ec unsafe (non const-time) multiplication using precomputed tables and w-ary non-adjacent form.
* @param acc accumulator point to add result of multiplication
* @returns point
*/
wNAFUnsafe(W, precomputes, n, acc = this.ZERO) {
const wo = calcWOpts(W, this.bits);
for (let window = 0; window < wo.windows; window++) {
if (n === _0n)
break; // Early-exit, skip 0 value
const { nextN, offset, isZero, isNeg } = calcOffsets(n, window, wo);
n = nextN;
if (isZero) {
// Window bits are 0: skip processing.
// Move to next window.
continue;
}
else {
const item = precomputes[offset];
acc = acc.add(isNeg ? item.negate() : item); // Re-using acc allows to save adds in MSM
}
}
assert0(n);
return acc;
}
getPrecomputes(W, point, transform) {
// Calculate precomputes on a first run, reuse them after
let comp = pointPrecomputes.get(point);
if (!comp) {
comp = this.precomputeWindow(point, W);
if (W !== 1) {
// Doing transform outside of if brings 15% perf hit
if (typeof transform === 'function')
comp = transform(comp);
pointPrecomputes.set(point, comp);
}
}
return comp;
}
cached(point, scalar, transform) {
const W = getW(point);
return this.wNAF(W, this.getPrecomputes(W, point, transform), scalar);
}
unsafe(point, scalar, transform, prev) {
const W = getW(point);
if (W === 1)
return this._unsafeLadder(point, scalar, prev); // For W=1 ladder is ~x2 faster
return this.wNAFUnsafe(W, this.getPrecomputes(W, point, transform), scalar, prev);
}
// We calculate precomputes for elliptic curve point multiplication
// using windowed method. This specifies window size and
// stores precomputed values. Usually only base point would be precomputed.
createCache(P, W) {
validateW(W, this.bits);
pointWindowSizes.set(P, W);
pointPrecomputes.delete(P);
}
hasCache(elm) {
return getW(elm) !== 1;
}
}
exports.wNAF = wNAF;
/**
* Endomorphism-specific multiplication for Koblitz curves.
* Cost: 128 dbl, 0-256 adds.
*/
function mulEndoUnsafe(Point, point, k1, k2) {
let acc = point;
let p1 = Point.ZERO;
let p2 = Point.ZERO;
while (k1 > _0n || k2 > _0n) {
if (k1 & _1n)
p1 = p1.add(acc);
if (k2 & _1n)
p2 = p2.add(acc);
acc = acc.double();
k1 >>= _1n;
k2 >>= _1n;
}
return { p1, p2 };
}
/**
* Pippenger algorithm for multi-scalar multiplication (MSM, Pa + Qb + Rc + ...).
* 30x faster vs naive addition on L=4096, 10x faster than precomputes.
* For N=254bit, L=1, it does: 1024 ADD + 254 DBL. For L=5: 1536 ADD + 254 DBL.
* Algorithmically constant-time (for same L), even when 1 point + scalar, or when scalar = 0.
* @param c Curve Point constructor
* @param fieldN field over CURVE.N - important that it's not over CURVE.P
* @param points array of L curve points
* @param scalars array of L scalars (aka secret keys / bigints)
*/
function pippenger(c, fieldN, points, scalars) {
// If we split scalars by some window (let's say 8 bits), every chunk will only
// take 256 buckets even if there are 4096 scalars, also re-uses double.
// TODO:
// - https://eprint.iacr.org/2024/750.pdf
// - https://tches.iacr.org/index.php/TCHES/article/view/10287
// 0 is accepted in scalars
validateMSMPoints(points, c);
validateMSMScalars(scalars, fieldN);
const plength = points.length;
const slength = scalars.length;
if (plength !== slength)
throw new Error('arrays of points and scalars must have equal length');
// if (plength === 0) throw new Error('array must be of length >= 2');
const zero = c.ZERO;
const wbits = (0, utils_ts_1.bitLen)(BigInt(plength));
let windowSize = 1; // bits
if (wbits > 12)
windowSize = wbits - 3;
else if (wbits > 4)
windowSize = wbits - 2;
else if (wbits > 0)
windowSize = 2;
const MASK = (0, utils_ts_1.bitMask)(windowSize);
const buckets = new Array(Number(MASK) + 1).fill(zero); // +1 for zero array
const lastBits = Math.floor((fieldN.BITS - 1) / windowSize) * windowSize;
let sum = zero;
for (let i = lastBits; i >= 0; i -= windowSize) {
buckets.fill(zero);
for (let j = 0; j < slength; j++) {
const scalar = scalars[j];
const wbits = Number((scalar >> BigInt(i)) & MASK);
buckets[wbits] = buckets[wbits].add(points[j]);
}
let resI = zero; // not using this will do small speed-up, but will lose ct
// Skip first bucket, because it is zero
for (let j = buckets.length - 1, sumI = zero; j > 0; j--) {
sumI = sumI.add(buckets[j]);
resI = resI.add(sumI);
}
sum = sum.add(resI);
if (i !== 0)
for (let j = 0; j < windowSize; j++)
sum = sum.double();
}
return sum;
}
/**
* Precomputed multi-scalar multiplication (MSM, Pa + Qb + Rc + ...).
* @param c Curve Point constructor
* @param fieldN field over CURVE.N - important that it's not over CURVE.P
* @param points array of L curve points
* @returns function which multiplies points with scaars
*/
function precomputeMSMUnsafe(c, fieldN, points, windowSize) {
/**
* Performance Analysis of Window-based Precomputation
*
* Base Case (256-bit scalar, 8-bit window):
* - Standard precomputation requires:
* - 31 additions per scalar × 256 scalars = 7,936 ops
* - Plus 255 summary additions = 8,191 total ops
* Note: Summary additions can be optimized via accumulator
*
* Chunked Precomputation Analysis:
* - Using 32 chunks requires:
* - 255 additions per chunk
* - 256 doublings
* - Total: (255 × 32) + 256 = 8,416 ops
*
* Memory Usage Comparison:
* Window Size | Standard Points | Chunked Points
* ------------|-----------------|---------------
* 4-bit | 520 | 15
* 8-bit | 4,224 | 255
* 10-bit | 13,824 | 1,023
* 16-bit | 557,056 | 65,535
*
* Key Advantages:
* 1. Enables larger window sizes due to reduced memory overhead
* 2. More efficient for smaller scalar counts:
* - 16 chunks: (16 × 255) + 256 = 4,336 ops
* - ~2x faster than standard 8,191 ops
*
* Limitations:
* - Not suitable for plain precomputes (requires 256 constant doublings)
* - Performance degrades with larger scalar counts:
* - Optimal for ~256 scalars
* - Less efficient for 4096+ scalars (Pippenger preferred)
*/
validateW(windowSize, fieldN.BITS);
validateMSMPoints(points, c);
const zero = c.ZERO;
const tableSize = 2 ** windowSize - 1; // table size (without zero)
const chunks = Math.ceil(fieldN.BITS / windowSize); // chunks of item
const MASK = (0, utils_ts_1.bitMask)(windowSize);
const tables = points.map((p) => {
const res = [];
for (let i = 0, acc = p; i < tableSize; i++) {
res.push(acc);
acc = acc.add(p);
}
return res;
});
return (scalars) => {
validateMSMScalars(scalars, fieldN);
if (scalars.length > points.length)
throw new Error('array of scalars must be smaller than array of points');
let res = zero;
for (let i = 0; i < chunks; i++) {
// No need to double if accumulator is still zero.
if (res !== zero)
for (let j = 0; j < windowSize; j++)
res = res.double();
const shiftBy = BigInt(chunks * windowSize - (i + 1) * windowSize);
for (let j = 0; j < scalars.length; j++) {
const n = scalars[j];
const curr = Number((n >> shiftBy) & MASK);
if (!curr)
continue; // skip zero scalars chunks
res = res.add(tables[j][curr - 1]);
}
}
return res;
};
}
// TODO: remove
/** @deprecated */
function validateBasic(curve) {
(0, modular_ts_1.validateField)(curve.Fp);
(0, utils_ts_1.validateObject)(curve, {
n: 'bigint',
h: 'bigint',
Gx: 'field',
Gy: 'field',
}, {
nBitLength: 'isSafeInteger',
nByteLength: 'isSafeInteger',
});
// Set defaults
return Object.freeze({
...(0, modular_ts_1.nLength)(curve.n, curve.nBitLength),
...curve,
...{ p: curve.Fp.ORDER },
});
}
function createField(order, field, isLE) {
if (field) {
if (field.ORDER !== order)
throw new Error('Field.ORDER must match order: Fp == p, Fn == n');
(0, modular_ts_1.validateField)(field);
return field;
}
else {
return (0, modular_ts_1.Field)(order, { isLE });
}
}
/** Validates CURVE opts and creates fields */
function _createCurveFields(type, CURVE, curveOpts = {}, FpFnLE) {
if (FpFnLE === undefined)
FpFnLE = type === 'edwards';
if (!CURVE || typeof CURVE !== 'object')
throw new Error(`expected valid ${type} CURVE object`);
for (const p of ['p', 'n', 'h']) {
const val = CURVE[p];
if (!(typeof val === 'bigint' && val > _0n))
throw new Error(`CURVE.${p} must be positive bigint`);
}
const Fp = createField(CURVE.p, curveOpts.Fp, FpFnLE);
const Fn = createField(CURVE.n, curveOpts.Fn, FpFnLE);
const _b = type === 'weierstrass' ? 'b' : 'd';
const params = ['Gx', 'Gy', 'a', _b];
for (const p of params) {
// @ts-ignore
if (!Fp.isValid(CURVE[p]))
throw new Error(`CURVE.${p} must be valid field element of CURVE.Fp`);
}
CURVE = Object.freeze(Object.assign({}, CURVE));
return { CURVE, Fp, Fn };
}
//# sourceMappingURL=curve.js.mapВыполнить команду
Для локальной разработки. Не используйте в интернете!