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- /*! noble-curves - MIT License (c) 2022 Paul Miller (paulmillr.com) */
- import { sha512 } from '@noble/hashes/sha512';
- import { concatBytes, randomBytes, utf8ToBytes } from '@noble/hashes/utils';
- import { twistedEdwards } from './abstract/edwards.js';
- import { createHasher, expand_message_xmd } from './abstract/hash-to-curve.js';
- import { Field, FpSqrtEven, isNegativeLE, mod, pow2 } from './abstract/modular.js';
- import { montgomery } from './abstract/montgomery.js';
- import { bytesToHex, bytesToNumberLE, ensureBytes, equalBytes, numberToBytesLE, } from './abstract/utils.js';
- /**
- * ed25519 Twisted Edwards curve with following addons:
- * - X25519 ECDH
- * - Ristretto cofactor elimination
- * - Elligator hash-to-group / point indistinguishability
- */
- const ED25519_P = BigInt('57896044618658097711785492504343953926634992332820282019728792003956564819949');
- // √(-1) aka √(a) aka 2^((p-1)/4)
- const ED25519_SQRT_M1 = /* @__PURE__ */ BigInt('19681161376707505956807079304988542015446066515923890162744021073123829784752');
- // prettier-ignore
- const _0n = BigInt(0), _1n = BigInt(1), _2n = BigInt(2), _3n = BigInt(3);
- // prettier-ignore
- const _5n = BigInt(5), _8n = BigInt(8);
- function ed25519_pow_2_252_3(x) {
- // prettier-ignore
- const _10n = BigInt(10), _20n = BigInt(20), _40n = BigInt(40), _80n = BigInt(80);
- const P = ED25519_P;
- const x2 = (x * x) % P;
- const b2 = (x2 * x) % P; // x^3, 11
- const b4 = (pow2(b2, _2n, P) * b2) % P; // x^15, 1111
- const b5 = (pow2(b4, _1n, P) * x) % P; // x^31
- const b10 = (pow2(b5, _5n, P) * b5) % P;
- const b20 = (pow2(b10, _10n, P) * b10) % P;
- const b40 = (pow2(b20, _20n, P) * b20) % P;
- const b80 = (pow2(b40, _40n, P) * b40) % P;
- const b160 = (pow2(b80, _80n, P) * b80) % P;
- const b240 = (pow2(b160, _80n, P) * b80) % P;
- const b250 = (pow2(b240, _10n, P) * b10) % P;
- const pow_p_5_8 = (pow2(b250, _2n, P) * x) % P;
- // ^ To pow to (p+3)/8, multiply it by x.
- return { pow_p_5_8, b2 };
- }
- function adjustScalarBytes(bytes) {
- // Section 5: For X25519, in order to decode 32 random bytes as an integer scalar,
- // set the three least significant bits of the first byte
- bytes[0] &= 248; // 0b1111_1000
- // and the most significant bit of the last to zero,
- bytes[31] &= 127; // 0b0111_1111
- // set the second most significant bit of the last byte to 1
- bytes[31] |= 64; // 0b0100_0000
- return bytes;
- }
- // sqrt(u/v)
- function uvRatio(u, v) {
- const P = ED25519_P;
- const v3 = mod(v * v * v, P); // v³
- const v7 = mod(v3 * v3 * v, P); // v⁷
- // (p+3)/8 and (p-5)/8
- const pow = ed25519_pow_2_252_3(u * v7).pow_p_5_8;
- let x = mod(u * v3 * pow, P); // (uv³)(uv⁷)^(p-5)/8
- const vx2 = mod(v * x * x, P); // vx²
- const root1 = x; // First root candidate
- const root2 = mod(x * ED25519_SQRT_M1, P); // Second root candidate
- const useRoot1 = vx2 === u; // If vx² = u (mod p), x is a square root
- const useRoot2 = vx2 === mod(-u, P); // If vx² = -u, set x <-- x * 2^((p-1)/4)
- const noRoot = vx2 === mod(-u * ED25519_SQRT_M1, P); // There is no valid root, vx² = -u√(-1)
- if (useRoot1)
- x = root1;
- if (useRoot2 || noRoot)
- x = root2; // We return root2 anyway, for const-time
- if (isNegativeLE(x, P))
- x = mod(-x, P);
- return { isValid: useRoot1 || useRoot2, value: x };
- }
- // Just in case
- export const ED25519_TORSION_SUBGROUP = [
- '0100000000000000000000000000000000000000000000000000000000000000',
- 'c7176a703d4dd84fba3c0b760d10670f2a2053fa2c39ccc64ec7fd7792ac037a',
- '0000000000000000000000000000000000000000000000000000000000000080',
- '26e8958fc2b227b045c3f489f2ef98f0d5dfac05d3c63339b13802886d53fc05',
- 'ecffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff7f',
- '26e8958fc2b227b045c3f489f2ef98f0d5dfac05d3c63339b13802886d53fc85',
- '0000000000000000000000000000000000000000000000000000000000000000',
- 'c7176a703d4dd84fba3c0b760d10670f2a2053fa2c39ccc64ec7fd7792ac03fa',
- ];
- const Fp = /* @__PURE__ */ (() => Field(ED25519_P, undefined, true))();
- const ed25519Defaults = /* @__PURE__ */ (() => ({
- // Param: a
- a: BigInt(-1), // Fp.create(-1) is proper; our way still works and is faster
- // d is equal to -121665/121666 over finite field.
- // Negative number is P - number, and division is invert(number, P)
- d: BigInt('37095705934669439343138083508754565189542113879843219016388785533085940283555'),
- // Finite field 𝔽p over which we'll do calculations; 2n**255n - 19n
- Fp,
- // Subgroup order: how many points curve has
- // 2n**252n + 27742317777372353535851937790883648493n;
- n: BigInt('7237005577332262213973186563042994240857116359379907606001950938285454250989'),
- // Cofactor
- h: _8n,
- // Base point (x, y) aka generator point
- Gx: BigInt('15112221349535400772501151409588531511454012693041857206046113283949847762202'),
- Gy: BigInt('46316835694926478169428394003475163141307993866256225615783033603165251855960'),
- hash: sha512,
- randomBytes,
- adjustScalarBytes,
- // dom2
- // Ratio of u to v. Allows us to combine inversion and square root. Uses algo from RFC8032 5.1.3.
- // Constant-time, u/√v
- uvRatio,
- }))();
- export const ed25519 = /* @__PURE__ */ (() => twistedEdwards(ed25519Defaults))();
- function ed25519_domain(data, ctx, phflag) {
- if (ctx.length > 255)
- throw new Error('Context is too big');
- return concatBytes(utf8ToBytes('SigEd25519 no Ed25519 collisions'), new Uint8Array([phflag ? 1 : 0, ctx.length]), ctx, data);
- }
- export const ed25519ctx = /* @__PURE__ */ (() => twistedEdwards({
- ...ed25519Defaults,
- domain: ed25519_domain,
- }))();
- export const ed25519ph = /* @__PURE__ */ (() => twistedEdwards(Object.assign({}, ed25519Defaults, {
- domain: ed25519_domain,
- prehash: sha512,
- })))();
- export const x25519 = /* @__PURE__ */ (() => montgomery({
- P: ED25519_P,
- a: BigInt(486662),
- montgomeryBits: 255, // n is 253 bits
- nByteLength: 32,
- Gu: BigInt(9),
- powPminus2: (x) => {
- const P = ED25519_P;
- // x^(p-2) aka x^(2^255-21)
- const { pow_p_5_8, b2 } = ed25519_pow_2_252_3(x);
- return mod(pow2(pow_p_5_8, _3n, P) * b2, P);
- },
- adjustScalarBytes,
- randomBytes,
- }))();
- /**
- * Converts ed25519 public key to x25519 public key. Uses formula:
- * * `(u, v) = ((1+y)/(1-y), sqrt(-486664)*u/x)`
- * * `(x, y) = (sqrt(-486664)*u/v, (u-1)/(u+1))`
- * @example
- * const someonesPub = ed25519.getPublicKey(ed25519.utils.randomPrivateKey());
- * const aPriv = x25519.utils.randomPrivateKey();
- * x25519.getSharedSecret(aPriv, edwardsToMontgomeryPub(someonesPub))
- */
- export function edwardsToMontgomeryPub(edwardsPub) {
- const { y } = ed25519.ExtendedPoint.fromHex(edwardsPub);
- const _1n = BigInt(1);
- return Fp.toBytes(Fp.create((_1n + y) * Fp.inv(_1n - y)));
- }
- export const edwardsToMontgomery = edwardsToMontgomeryPub; // deprecated
- /**
- * Converts ed25519 secret key to x25519 secret key.
- * @example
- * const someonesPub = x25519.getPublicKey(x25519.utils.randomPrivateKey());
- * const aPriv = ed25519.utils.randomPrivateKey();
- * x25519.getSharedSecret(edwardsToMontgomeryPriv(aPriv), someonesPub)
- */
- export function edwardsToMontgomeryPriv(edwardsPriv) {
- const hashed = ed25519Defaults.hash(edwardsPriv.subarray(0, 32));
- return ed25519Defaults.adjustScalarBytes(hashed).subarray(0, 32);
- }
- // Hash To Curve Elligator2 Map (NOTE: different from ristretto255 elligator)
- // NOTE: very important part is usage of FpSqrtEven for ELL2_C1_EDWARDS, since
- // SageMath returns different root first and everything falls apart
- const ELL2_C1 = /* @__PURE__ */ (() => (Fp.ORDER + _3n) / _8n)(); // 1. c1 = (q + 3) / 8 # Integer arithmetic
- const ELL2_C2 = /* @__PURE__ */ (() => Fp.pow(_2n, ELL2_C1))(); // 2. c2 = 2^c1
- const ELL2_C3 = /* @__PURE__ */ (() => Fp.sqrt(Fp.neg(Fp.ONE)))(); // 3. c3 = sqrt(-1)
- // prettier-ignore
- function map_to_curve_elligator2_curve25519(u) {
- const ELL2_C4 = (Fp.ORDER - _5n) / _8n; // 4. c4 = (q - 5) / 8 # Integer arithmetic
- const ELL2_J = BigInt(486662);
- let tv1 = Fp.sqr(u); // 1. tv1 = u^2
- tv1 = Fp.mul(tv1, _2n); // 2. tv1 = 2 * tv1
- let xd = Fp.add(tv1, Fp.ONE); // 3. xd = tv1 + 1 # Nonzero: -1 is square (mod p), tv1 is not
- let x1n = Fp.neg(ELL2_J); // 4. x1n = -J # x1 = x1n / xd = -J / (1 + 2 * u^2)
- let tv2 = Fp.sqr(xd); // 5. tv2 = xd^2
- let gxd = Fp.mul(tv2, xd); // 6. gxd = tv2 * xd # gxd = xd^3
- let gx1 = Fp.mul(tv1, ELL2_J); // 7. gx1 = J * tv1 # x1n + J * xd
- gx1 = Fp.mul(gx1, x1n); // 8. gx1 = gx1 * x1n # x1n^2 + J * x1n * xd
- gx1 = Fp.add(gx1, tv2); // 9. gx1 = gx1 + tv2 # x1n^2 + J * x1n * xd + xd^2
- gx1 = Fp.mul(gx1, x1n); // 10. gx1 = gx1 * x1n # x1n^3 + J * x1n^2 * xd + x1n * xd^2
- let tv3 = Fp.sqr(gxd); // 11. tv3 = gxd^2
- tv2 = Fp.sqr(tv3); // 12. tv2 = tv3^2 # gxd^4
- tv3 = Fp.mul(tv3, gxd); // 13. tv3 = tv3 * gxd # gxd^3
- tv3 = Fp.mul(tv3, gx1); // 14. tv3 = tv3 * gx1 # gx1 * gxd^3
- tv2 = Fp.mul(tv2, tv3); // 15. tv2 = tv2 * tv3 # gx1 * gxd^7
- let y11 = Fp.pow(tv2, ELL2_C4); // 16. y11 = tv2^c4 # (gx1 * gxd^7)^((p - 5) / 8)
- y11 = Fp.mul(y11, tv3); // 17. y11 = y11 * tv3 # gx1*gxd^3*(gx1*gxd^7)^((p-5)/8)
- let y12 = Fp.mul(y11, ELL2_C3); // 18. y12 = y11 * c3
- tv2 = Fp.sqr(y11); // 19. tv2 = y11^2
- tv2 = Fp.mul(tv2, gxd); // 20. tv2 = tv2 * gxd
- let e1 = Fp.eql(tv2, gx1); // 21. e1 = tv2 == gx1
- let y1 = Fp.cmov(y12, y11, e1); // 22. y1 = CMOV(y12, y11, e1) # If g(x1) is square, this is its sqrt
- let x2n = Fp.mul(x1n, tv1); // 23. x2n = x1n * tv1 # x2 = x2n / xd = 2 * u^2 * x1n / xd
- let y21 = Fp.mul(y11, u); // 24. y21 = y11 * u
- y21 = Fp.mul(y21, ELL2_C2); // 25. y21 = y21 * c2
- let y22 = Fp.mul(y21, ELL2_C3); // 26. y22 = y21 * c3
- let gx2 = Fp.mul(gx1, tv1); // 27. gx2 = gx1 * tv1 # g(x2) = gx2 / gxd = 2 * u^2 * g(x1)
- tv2 = Fp.sqr(y21); // 28. tv2 = y21^2
- tv2 = Fp.mul(tv2, gxd); // 29. tv2 = tv2 * gxd
- let e2 = Fp.eql(tv2, gx2); // 30. e2 = tv2 == gx2
- let y2 = Fp.cmov(y22, y21, e2); // 31. y2 = CMOV(y22, y21, e2) # If g(x2) is square, this is its sqrt
- tv2 = Fp.sqr(y1); // 32. tv2 = y1^2
- tv2 = Fp.mul(tv2, gxd); // 33. tv2 = tv2 * gxd
- let e3 = Fp.eql(tv2, gx1); // 34. e3 = tv2 == gx1
- let xn = Fp.cmov(x2n, x1n, e3); // 35. xn = CMOV(x2n, x1n, e3) # If e3, x = x1, else x = x2
- let y = Fp.cmov(y2, y1, e3); // 36. y = CMOV(y2, y1, e3) # If e3, y = y1, else y = y2
- let e4 = Fp.isOdd(y); // 37. e4 = sgn0(y) == 1 # Fix sign of y
- y = Fp.cmov(y, Fp.neg(y), e3 !== e4); // 38. y = CMOV(y, -y, e3 XOR e4)
- return { xMn: xn, xMd: xd, yMn: y, yMd: _1n }; // 39. return (xn, xd, y, 1)
- }
- const ELL2_C1_EDWARDS = /* @__PURE__ */ (() => FpSqrtEven(Fp, Fp.neg(BigInt(486664))))(); // sgn0(c1) MUST equal 0
- function map_to_curve_elligator2_edwards25519(u) {
- const { xMn, xMd, yMn, yMd } = map_to_curve_elligator2_curve25519(u); // 1. (xMn, xMd, yMn, yMd) =
- // map_to_curve_elligator2_curve25519(u)
- let xn = Fp.mul(xMn, yMd); // 2. xn = xMn * yMd
- xn = Fp.mul(xn, ELL2_C1_EDWARDS); // 3. xn = xn * c1
- let xd = Fp.mul(xMd, yMn); // 4. xd = xMd * yMn # xn / xd = c1 * xM / yM
- let yn = Fp.sub(xMn, xMd); // 5. yn = xMn - xMd
- let yd = Fp.add(xMn, xMd); // 6. yd = xMn + xMd # (n / d - 1) / (n / d + 1) = (n - d) / (n + d)
- let tv1 = Fp.mul(xd, yd); // 7. tv1 = xd * yd
- let e = Fp.eql(tv1, Fp.ZERO); // 8. e = tv1 == 0
- xn = Fp.cmov(xn, Fp.ZERO, e); // 9. xn = CMOV(xn, 0, e)
- xd = Fp.cmov(xd, Fp.ONE, e); // 10. xd = CMOV(xd, 1, e)
- yn = Fp.cmov(yn, Fp.ONE, e); // 11. yn = CMOV(yn, 1, e)
- yd = Fp.cmov(yd, Fp.ONE, e); // 12. yd = CMOV(yd, 1, e)
- const inv = Fp.invertBatch([xd, yd]); // batch division
- return { x: Fp.mul(xn, inv[0]), y: Fp.mul(yn, inv[1]) }; // 13. return (xn, xd, yn, yd)
- }
- const htf = /* @__PURE__ */ (() => createHasher(ed25519.ExtendedPoint, (scalars) => map_to_curve_elligator2_edwards25519(scalars[0]), {
- DST: 'edwards25519_XMD:SHA-512_ELL2_RO_',
- encodeDST: 'edwards25519_XMD:SHA-512_ELL2_NU_',
- p: Fp.ORDER,
- m: 1,
- k: 128,
- expand: 'xmd',
- hash: sha512,
- }))();
- export const hashToCurve = /* @__PURE__ */ (() => htf.hashToCurve)();
- export const encodeToCurve = /* @__PURE__ */ (() => htf.encodeToCurve)();
- function assertRstPoint(other) {
- if (!(other instanceof RistPoint))
- throw new Error('RistrettoPoint expected');
- }
- // √(-1) aka √(a) aka 2^((p-1)/4)
- const SQRT_M1 = ED25519_SQRT_M1;
- // √(ad - 1)
- const SQRT_AD_MINUS_ONE = /* @__PURE__ */ BigInt('25063068953384623474111414158702152701244531502492656460079210482610430750235');
- // 1 / √(a-d)
- const INVSQRT_A_MINUS_D = /* @__PURE__ */ BigInt('54469307008909316920995813868745141605393597292927456921205312896311721017578');
- // 1-d²
- const ONE_MINUS_D_SQ = /* @__PURE__ */ BigInt('1159843021668779879193775521855586647937357759715417654439879720876111806838');
- // (d-1)²
- const D_MINUS_ONE_SQ = /* @__PURE__ */ BigInt('40440834346308536858101042469323190826248399146238708352240133220865137265952');
- // Calculates 1/√(number)
- const invertSqrt = (number) => uvRatio(_1n, number);
- const MAX_255B = /* @__PURE__ */ BigInt('0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff');
- const bytes255ToNumberLE = (bytes) => ed25519.CURVE.Fp.create(bytesToNumberLE(bytes) & MAX_255B);
- // Computes Elligator map for Ristretto
- // https://ristretto.group/formulas/elligator.html
- function calcElligatorRistrettoMap(r0) {
- const { d } = ed25519.CURVE;
- const P = ed25519.CURVE.Fp.ORDER;
- const mod = ed25519.CURVE.Fp.create;
- const r = mod(SQRT_M1 * r0 * r0); // 1
- const Ns = mod((r + _1n) * ONE_MINUS_D_SQ); // 2
- let c = BigInt(-1); // 3
- const D = mod((c - d * r) * mod(r + d)); // 4
- let { isValid: Ns_D_is_sq, value: s } = uvRatio(Ns, D); // 5
- let s_ = mod(s * r0); // 6
- if (!isNegativeLE(s_, P))
- s_ = mod(-s_);
- if (!Ns_D_is_sq)
- s = s_; // 7
- if (!Ns_D_is_sq)
- c = r; // 8
- const Nt = mod(c * (r - _1n) * D_MINUS_ONE_SQ - D); // 9
- const s2 = s * s;
- const W0 = mod((s + s) * D); // 10
- const W1 = mod(Nt * SQRT_AD_MINUS_ONE); // 11
- const W2 = mod(_1n - s2); // 12
- const W3 = mod(_1n + s2); // 13
- return new ed25519.ExtendedPoint(mod(W0 * W3), mod(W2 * W1), mod(W1 * W3), mod(W0 * W2));
- }
- /**
- * Each ed25519/ExtendedPoint has 8 different equivalent points. This can be
- * a source of bugs for protocols like ring signatures. Ristretto was created to solve this.
- * Ristretto point operates in X:Y:Z:T extended coordinates like ExtendedPoint,
- * but it should work in its own namespace: do not combine those two.
- * https://datatracker.ietf.org/doc/html/draft-irtf-cfrg-ristretto255-decaf448
- */
- class RistPoint {
- // Private property to discourage combining ExtendedPoint + RistrettoPoint
- // Always use Ristretto encoding/decoding instead.
- constructor(ep) {
- this.ep = ep;
- }
- static fromAffine(ap) {
- return new RistPoint(ed25519.ExtendedPoint.fromAffine(ap));
- }
- /**
- * Takes uniform output of 64-byte hash function like sha512 and converts it to `RistrettoPoint`.
- * The hash-to-group operation applies Elligator twice and adds the results.
- * **Note:** this is one-way map, there is no conversion from point to hash.
- * https://ristretto.group/formulas/elligator.html
- * @param hex 64-byte output of a hash function
- */
- static hashToCurve(hex) {
- hex = ensureBytes('ristrettoHash', hex, 64);
- const r1 = bytes255ToNumberLE(hex.slice(0, 32));
- const R1 = calcElligatorRistrettoMap(r1);
- const r2 = bytes255ToNumberLE(hex.slice(32, 64));
- const R2 = calcElligatorRistrettoMap(r2);
- return new RistPoint(R1.add(R2));
- }
- /**
- * Converts ristretto-encoded string to ristretto point.
- * https://ristretto.group/formulas/decoding.html
- * @param hex Ristretto-encoded 32 bytes. Not every 32-byte string is valid ristretto encoding
- */
- static fromHex(hex) {
- hex = ensureBytes('ristrettoHex', hex, 32);
- const { a, d } = ed25519.CURVE;
- const P = ed25519.CURVE.Fp.ORDER;
- const mod = ed25519.CURVE.Fp.create;
- const emsg = 'RistrettoPoint.fromHex: the hex is not valid encoding of RistrettoPoint';
- const s = bytes255ToNumberLE(hex);
- // 1. Check that s_bytes is the canonical encoding of a field element, or else abort.
- // 3. Check that s is non-negative, or else abort
- if (!equalBytes(numberToBytesLE(s, 32), hex) || isNegativeLE(s, P))
- throw new Error(emsg);
- const s2 = mod(s * s);
- const u1 = mod(_1n + a * s2); // 4 (a is -1)
- const u2 = mod(_1n - a * s2); // 5
- const u1_2 = mod(u1 * u1);
- const u2_2 = mod(u2 * u2);
- const v = mod(a * d * u1_2 - u2_2); // 6
- const { isValid, value: I } = invertSqrt(mod(v * u2_2)); // 7
- const Dx = mod(I * u2); // 8
- const Dy = mod(I * Dx * v); // 9
- let x = mod((s + s) * Dx); // 10
- if (isNegativeLE(x, P))
- x = mod(-x); // 10
- const y = mod(u1 * Dy); // 11
- const t = mod(x * y); // 12
- if (!isValid || isNegativeLE(t, P) || y === _0n)
- throw new Error(emsg);
- return new RistPoint(new ed25519.ExtendedPoint(x, y, _1n, t));
- }
- /**
- * Encodes ristretto point to Uint8Array.
- * https://ristretto.group/formulas/encoding.html
- */
- toRawBytes() {
- let { ex: x, ey: y, ez: z, et: t } = this.ep;
- const P = ed25519.CURVE.Fp.ORDER;
- const mod = ed25519.CURVE.Fp.create;
- const u1 = mod(mod(z + y) * mod(z - y)); // 1
- const u2 = mod(x * y); // 2
- // Square root always exists
- const u2sq = mod(u2 * u2);
- const { value: invsqrt } = invertSqrt(mod(u1 * u2sq)); // 3
- const D1 = mod(invsqrt * u1); // 4
- const D2 = mod(invsqrt * u2); // 5
- const zInv = mod(D1 * D2 * t); // 6
- let D; // 7
- if (isNegativeLE(t * zInv, P)) {
- let _x = mod(y * SQRT_M1);
- let _y = mod(x * SQRT_M1);
- x = _x;
- y = _y;
- D = mod(D1 * INVSQRT_A_MINUS_D);
- }
- else {
- D = D2; // 8
- }
- if (isNegativeLE(x * zInv, P))
- y = mod(-y); // 9
- let s = mod((z - y) * D); // 10 (check footer's note, no sqrt(-a))
- if (isNegativeLE(s, P))
- s = mod(-s);
- return numberToBytesLE(s, 32); // 11
- }
- toHex() {
- return bytesToHex(this.toRawBytes());
- }
- toString() {
- return this.toHex();
- }
- // Compare one point to another.
- equals(other) {
- assertRstPoint(other);
- const { ex: X1, ey: Y1 } = this.ep;
- const { ex: X2, ey: Y2 } = other.ep;
- const mod = ed25519.CURVE.Fp.create;
- // (x1 * y2 == y1 * x2) | (y1 * y2 == x1 * x2)
- const one = mod(X1 * Y2) === mod(Y1 * X2);
- const two = mod(Y1 * Y2) === mod(X1 * X2);
- return one || two;
- }
- add(other) {
- assertRstPoint(other);
- return new RistPoint(this.ep.add(other.ep));
- }
- subtract(other) {
- assertRstPoint(other);
- return new RistPoint(this.ep.subtract(other.ep));
- }
- multiply(scalar) {
- return new RistPoint(this.ep.multiply(scalar));
- }
- multiplyUnsafe(scalar) {
- return new RistPoint(this.ep.multiplyUnsafe(scalar));
- }
- double() {
- return new RistPoint(this.ep.double());
- }
- negate() {
- return new RistPoint(this.ep.negate());
- }
- }
- export const RistrettoPoint = /* @__PURE__ */ (() => {
- if (!RistPoint.BASE)
- RistPoint.BASE = new RistPoint(ed25519.ExtendedPoint.BASE);
- if (!RistPoint.ZERO)
- RistPoint.ZERO = new RistPoint(ed25519.ExtendedPoint.ZERO);
- return RistPoint;
- })();
- // Hashing to ristretto255. https://www.rfc-editor.org/rfc/rfc9380#appendix-B
- export const hashToRistretto255 = (msg, options) => {
- const d = options.DST;
- const DST = typeof d === 'string' ? utf8ToBytes(d) : d;
- const uniform_bytes = expand_message_xmd(msg, DST, 64, sha512);
- const P = RistPoint.hashToCurve(uniform_bytes);
- return P;
- };
- export const hash_to_ristretto255 = hashToRistretto255; // legacy
- //# sourceMappingURL=ed25519.js.map
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