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"use strict"; Object.defineProperty(exports, "__esModule", { value: true }); exports.bitMask = void 0; exports.isBytes = isBytes; exports.abytes = abytes; exports.abool = abool; exports.bytesToHex = bytesToHex; exports.hexToNumber = hexToNumber; exports.hexToBytes = hexToBytes; exports.bytesToNumberBE = bytesToNumberBE; exports.bytesToNumberLE = bytesToNumberLE; exports.numberToBytesBE = numberToBytesBE; exports.numberToBytesLE = numberToBytesLE; exports.ensureBytes = ensureBytes; exports.concatBytes = concatBytes; exports.inRange = inRange; exports.aInRange = aInRange; exports.bitLen = bitLen; exports.validateObject = validateObject; exports.memoized = memoized; const _0n = /* @__PURE__ */ BigInt(0); const _1n = /* @__PURE__ */ BigInt(1); const _2n = /* @__PURE__ */ BigInt(2); function isBytes(a) { return a instanceof Uint8Array || (ArrayBuffer.isView(a) && a.constructor.name === 'Uint8Array'); } function abytes(item) { if (!isBytes(item)) throw new Error('Uint8Array expected'); } function abool(title, value) { if (typeof value !== 'boolean') throw new Error(title + ' boolean expected, got ' + value); } // Array where index 0xf0 (240) is mapped to string 'f0' const hexes = /* @__PURE__ */ Array.from({ length: 256 }, (_, i) => i.toString(16).padStart(2, '0')); /** * @example bytesToHex(Uint8Array.from([0xca, 0xfe, 0x01, 0x23])) // 'cafe0123' */ function bytesToHex(bytes) { abytes(bytes); // pre-caching improves the speed 6x let hex = ''; for (let i = 0; i < bytes.length; i++) { hex += hexes[bytes[i]]; } return hex; } function hexToNumber(hex) { if (typeof hex !== 'string') throw new Error('hex string expected, got ' + typeof hex); return hex === '' ? _0n : BigInt('0x' + hex); // Big Endian } // We use optimized technique to convert hex string to byte array const asciis = { _0: 48, _9: 57, A: 65, F: 70, a: 97, f: 102 }; function asciiToBase16(ch) { if (ch >= asciis._0 && ch <= asciis._9) return ch - asciis._0; // '2' => 50-48 if (ch >= asciis.A && ch <= asciis.F) return ch - (asciis.A - 10); // 'B' => 66-(65-10) if (ch >= asciis.a && ch <= asciis.f) return ch - (asciis.a - 10); // 'b' => 98-(97-10) return; } /** * @example hexToBytes('cafe0123') // Uint8Array.from([0xca, 0xfe, 0x01, 0x23]) */ function hexToBytes(hex) { if (typeof hex !== 'string') throw new Error('hex string expected, got ' + typeof hex); const hl = hex.length; const al = hl / 2; if (hl % 2) throw new Error('hex string expected, got unpadded hex of length ' + hl); const array = new Uint8Array(al); for (let ai = 0, hi = 0; ai < al; ai++, hi += 2) { const n1 = asciiToBase16(hex.charCodeAt(hi)); const n2 = asciiToBase16(hex.charCodeAt(hi + 1)); if (n1 === undefined || n2 === undefined) { const char = hex[hi] + hex[hi + 1]; throw new Error('hex string expected, got non-hex character "' + char + '" at index ' + hi); } array[ai] = n1 * 16 + n2; // multiply first octet, e.g. 'a3' => 10*16+3 => 160 + 3 => 163 } return array; } // BE: Big Endian, LE: Little Endian function bytesToNumberBE(bytes) { return hexToNumber(bytesToHex(bytes)); } function bytesToNumberLE(bytes) { abytes(bytes); return hexToNumber(bytesToHex(Uint8Array.from(bytes).reverse())); } function numberToBytesBE(n, len) { return hexToBytes(n.toString(16).padStart(len * 2, '0')); } function numberToBytesLE(n, len) { return numberToBytesBE(n, len).reverse(); } /** * Takes hex string or Uint8Array, converts to Uint8Array. * Validates output length. * Will throw error for other types. * @param title descriptive title for an error e.g. 'private key' * @param hex hex string or Uint8Array * @param expectedLength optional, will compare to result array's length * @returns */ function ensureBytes(title, hex, expectedLength) { let res; if (typeof hex === 'string') { try { res = hexToBytes(hex); } catch (e) { throw new Error(title + ' must be hex string or Uint8Array, cause: ' + e); } } else if (isBytes(hex)) { // Uint8Array.from() instead of hash.slice() because node.js Buffer // is instance of Uint8Array, and its slice() creates **mutable** copy res = Uint8Array.from(hex); } else { throw new Error(title + ' must be hex string or Uint8Array'); } const len = res.length; if (typeof expectedLength === 'number' && len !== expectedLength) throw new Error(title + ' of length ' + expectedLength + ' expected, got ' + len); return res; } /** * Copies several Uint8Arrays into one. */ function concatBytes(...arrays) { let sum = 0; for (let i = 0; i < arrays.length; i++) { const a = arrays[i]; abytes(a); sum += a.length; } const res = new Uint8Array(sum); for (let i = 0, pad = 0; i < arrays.length; i++) { const a = arrays[i]; res.set(a, pad); pad += a.length; } return res; } // Is positive bigint const isPosBig = (n) => typeof n === 'bigint' && _0n <= n; function inRange(n, min, max) { return isPosBig(n) && isPosBig(min) && isPosBig(max) && min <= n && n < max; } /** * Asserts min <= n < max. NOTE: It's < max and not <= max. * @example * aInRange('x', x, 1n, 256n); // would assume x is in (1n..255n) */ function aInRange(title, n, min, max) { // Why min <= n < max and not a (min < n < max) OR b (min <= n <= max)? // consider P=256n, min=0n, max=P // - a for min=0 would require -1: `inRange('x', x, -1n, P)` // - b would commonly require subtraction: `inRange('x', x, 0n, P - 1n)` // - our way is the cleanest: `inRange('x', x, 0n, P) if (!inRange(n, min, max)) throw new Error('expected valid ' + title + ': ' + min + ' <= n < ' + max + ', got ' + n); } // Bit operations /** * Calculates amount of bits in a bigint. * Same as `n.toString(2).length` */ function bitLen(n) { let len; for (len = 0; n > _0n; n >>= _1n, len += 1) ; return len; } /** * Calculate mask for N bits. Not using ** operator with bigints because of old engines. * Same as BigInt(`0b${Array(i).fill('1').join('')}`) */ const bitMask = (n) => (_2n << BigInt(n - 1)) - _1n; exports.bitMask = bitMask; // Validating curves and fields const validatorFns = { bigint: (val) => typeof val === 'bigint', function: (val) => typeof val === 'function', boolean: (val) => typeof val === 'boolean', string: (val) => typeof val === 'string', stringOrUint8Array: (val) => typeof val === 'string' || isBytes(val), isSafeInteger: (val) => Number.isSafeInteger(val), array: (val) => Array.isArray(val), field: (val, object) => object.Fp.isValid(val), hash: (val) => typeof val === 'function' && Number.isSafeInteger(val.outputLen), }; // type Record<K extends string | number | symbol, T> = { [P in K]: T; } function validateObject(object, validators, optValidators = {}) { const checkField = (fieldName, type, isOptional) => { const checkVal = validatorFns[type]; if (typeof checkVal !== 'function') throw new Error('invalid validator function'); const val = object[fieldName]; if (isOptional && val === undefined) return; if (!checkVal(val, object)) { throw new Error('param ' + String(fieldName) + ' is invalid. Expected ' + type + ', got ' + val); } }; for (const [fieldName, type] of Object.entries(validators)) checkField(fieldName, type, false); for (const [fieldName, type] of Object.entries(optValidators)) checkField(fieldName, type, true); return object; } /** * Memoizes (caches) computation result. * Uses WeakMap: the value is going auto-cleaned by GC after last reference is removed. */ function memoized(fn) { const map = new WeakMap(); return (arg, ...args) => { const val = map.get(arg); if (val !== undefined) return val; const computed = fn(arg, ...args); map.set(arg, computed); return computed; }; }