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drand-client

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A client to the drand randomness beacon network.

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{ "version": 3, "sources": ["../../node_modules/@noble/hashes/src/cryptoNode.ts", "../../node_modules/@noble/hashes/src/utils.ts", "../../node_modules/@noble/curves/src/abstract/utils.ts", "../../node_modules/@noble/curves/src/abstract/modular.ts", "../../node_modules/@noble/curves/src/abstract/hash-to-curve.ts", "../../node_modules/@noble/curves/src/abstract/curve.ts", "../../node_modules/@noble/curves/src/abstract/weierstrass.ts", "../../node_modules/@noble/curves/src/abstract/bls.ts", "../../node_modules/@noble/curves/src/abstract/tower.ts", "../../node_modules/@noble/hashes/src/_u64.ts", "../../node_modules/@noble/hashes/src/sha3.ts", "../../node_modules/@kevincharm/noble-bn254-drand/dist/src/bn254.js", "../../node_modules/@kevincharm/noble-bn254-drand/dist/src/index.js", "../../lib/index.ts", "../../lib/version.ts", "../../lib/util.ts", "../../lib/http-caching-chain.ts", "../../lib/http-chain-client.ts", "../../lib/speedtest.ts", "../../lib/fastest-node-client.ts", "../../lib/multi-beacon-node.ts", "../../node_modules/@noble/hashes/src/cryptoNode.ts", "../../node_modules/@noble/hashes/src/utils.ts", "../../node_modules/@noble/hashes/src/_md.ts", "../../node_modules/@noble/hashes/src/_u64.ts", "../../node_modules/@noble/hashes/src/sha2.ts", "../../node_modules/@noble/curves/src/abstract/utils.ts", "../../node_modules/@noble/curves/src/abstract/modular.ts", "../../node_modules/@noble/curves/src/abstract/hash-to-curve.ts", "../../node_modules/@noble/curves/src/abstract/curve.ts", "../../node_modules/@noble/curves/src/abstract/weierstrass.ts", "../../node_modules/@noble/curves/src/abstract/bls.ts", "../../node_modules/@noble/curves/src/abstract/tower.ts", "../../node_modules/@noble/curves/src/bls12-381.ts", "../../lib/beacon-verification.ts", "../../node_modules/@noble/hashes/src/sha3.ts", "../../lib/defaults.ts"], "sourcesContent": ["/**\n * Internal webcrypto alias.\n * We prefer WebCrypto aka globalThis.crypto, which exists in node.js 16+.\n * Falls back to Node.js built-in crypto for Node.js <=v14.\n * See utils.ts for details.\n * @module\n */\n// @ts-ignore\nimport * as nc from 'node:crypto';\nexport const crypto: any =\n nc && typeof nc === 'object' && 'webcrypto' in nc\n ? (nc.webcrypto as any)\n : nc && typeof nc === 'object' && 'randomBytes' in nc\n ? nc\n : undefined;\n", "/**\n * Utilities for hex, bytes, CSPRNG.\n * @module\n */\n/*! noble-hashes - MIT License (c) 2022 Paul Miller (paulmillr.com) */\n\n// We use WebCrypto aka globalThis.crypto, which exists in browsers and node.js 16+.\n// node.js versions earlier than v19 don't declare it in global scope.\n// For node.js, package.json#exports field mapping rewrites import\n// from `crypto` to `cryptoNode`, which imports native module.\n// Makes the utils un-importable in browsers without a bundler.\n// Once node.js 18 is deprecated (2025-04-30), we can just drop the import.\nimport { crypto } from '@noble/hashes/crypto';\n\n/** Checks if something is Uint8Array. Be careful: nodejs Buffer will return true. */\nexport function isBytes(a: unknown): a is Uint8Array {\n return a instanceof Uint8Array || (ArrayBuffer.isView(a) && a.constructor.name === 'Uint8Array');\n}\n\n/** Asserts something is positive integer. */\nexport function anumber(n: number): void {\n if (!Number.isSafeInteger(n) || n < 0) throw new Error('positive integer expected, got ' + n);\n}\n\n/** Asserts something is Uint8Array. */\nexport function abytes(b: Uint8Array | undefined, ...lengths: number[]): void {\n if (!isBytes(b)) throw new Error('Uint8Array expected');\n if (lengths.length > 0 && !lengths.includes(b.length))\n throw new Error('Uint8Array expected of length ' + lengths + ', got length=' + b.length);\n}\n\n/** Asserts something is hash */\nexport function ahash(h: IHash): void {\n if (typeof h !== 'function' || typeof h.create !== 'function')\n throw new Error('Hash should be wrapped by utils.createHasher');\n anumber(h.outputLen);\n anumber(h.blockLen);\n}\n\n/** Asserts a hash instance has not been destroyed / finished */\nexport function aexists(instance: any, checkFinished = true): void {\n if (instance.destroyed) throw new Error('Hash instance has been destroyed');\n if (checkFinished && instance.finished) throw new Error('Hash#digest() has already been called');\n}\n\n/** Asserts output is properly-sized byte array */\nexport function aoutput(out: any, instance: any): void {\n abytes(out);\n const min = instance.outputLen;\n if (out.length < min) {\n throw new Error('digestInto() expects output buffer of length at least ' + min);\n }\n}\n\n/** Generic type encompassing 8/16/32-byte arrays - but not 64-byte. */\n// prettier-ignore\nexport type TypedArray = Int8Array | Uint8ClampedArray | Uint8Array |\n Uint16Array | Int16Array | Uint32Array | Int32Array;\n\n/** Cast u8 / u16 / u32 to u8. */\nexport function u8(arr: TypedArray): Uint8Array {\n return new Uint8Array(arr.buffer, arr.byteOffset, arr.byteLength);\n}\n\n/** Cast u8 / u16 / u32 to u32. */\nexport function u32(arr: TypedArray): Uint32Array {\n return new Uint32Array(arr.buffer, arr.byteOffset, Math.floor(arr.byteLength / 4));\n}\n\n/** Zeroize a byte array. Warning: JS provides no guarantees. */\nexport function clean(...arrays: TypedArray[]): void {\n for (let i = 0; i < arrays.length; i++) {\n arrays[i].fill(0);\n }\n}\n\n/** Create DataView of an array for easy byte-level manipulation. */\nexport function createView(arr: TypedArray): DataView {\n return new DataView(arr.buffer, arr.byteOffset, arr.byteLength);\n}\n\n/** The rotate right (circular right shift) operation for uint32 */\nexport function rotr(word: number, shift: number): number {\n return (word << (32 - shift)) | (word >>> shift);\n}\n\n/** The rotate left (circular left shift) operation for uint32 */\nexport function rotl(word: number, shift: number): number {\n return (word << shift) | ((word >>> (32 - shift)) >>> 0);\n}\n\n/** Is current platform little-endian? Most are. Big-Endian platform: IBM */\nexport const isLE: boolean = /* @__PURE__ */ (() =>\n new Uint8Array(new Uint32Array([0x11223344]).buffer)[0] === 0x44)();\n\n/** The byte swap operation for uint32 */\nexport function byteSwap(word: number): number {\n return (\n ((word << 24) & 0xff000000) |\n ((word << 8) & 0xff0000) |\n ((word >>> 8) & 0xff00) |\n ((word >>> 24) & 0xff)\n );\n}\n/** Conditionally byte swap if on a big-endian platform */\nexport const swap8IfBE: (n: number) => number = isLE\n ? (n: number) => n\n : (n: number) => byteSwap(n);\n\n/** @deprecated */\nexport const byteSwapIfBE: typeof swap8IfBE = swap8IfBE;\n/** In place byte swap for Uint32Array */\nexport function byteSwap32(arr: Uint32Array): Uint32Array {\n for (let i = 0; i < arr.length; i++) {\n arr[i] = byteSwap(arr[i]);\n }\n return arr;\n}\n\nexport const swap32IfBE: (u: Uint32Array) => Uint32Array = isLE\n ? (u: Uint32Array) => u\n : byteSwap32;\n\n// Built-in hex conversion https://caniuse.com/mdn-javascript_builtins_uint8array_fromhex\nconst hasHexBuiltin: boolean = /* @__PURE__ */ (() =>\n // @ts-ignore\n typeof Uint8Array.from([]).toHex === 'function' && typeof Uint8Array.fromHex === 'function')();\n\n// Array where index 0xf0 (240) is mapped to string 'f0'\nconst hexes = /* @__PURE__ */ Array.from({ length: 256 }, (_, i) =>\n i.toString(16).padStart(2, '0')\n);\n\n/**\n * Convert byte array to hex string. Uses built-in function, when available.\n * @example bytesToHex(Uint8Array.from([0xca, 0xfe, 0x01, 0x23])) // 'cafe0123'\n */\nexport function bytesToHex(bytes: Uint8Array): string {\n abytes(bytes);\n // @ts-ignore\n if (hasHexBuiltin) return bytes.toHex();\n // pre-caching improves the speed 6x\n let hex = '';\n for (let i = 0; i < bytes.length; i++) {\n hex += hexes[bytes[i]];\n }\n return hex;\n}\n\n// We use optimized technique to convert hex string to byte array\nconst asciis = { _0: 48, _9: 57, A: 65, F: 70, a: 97, f: 102 } as const;\nfunction asciiToBase16(ch: number): number | undefined {\n if (ch >= asciis._0 && ch <= asciis._9) return ch - asciis._0; // '2' => 50-48\n if (ch >= asciis.A && ch <= asciis.F) return ch - (asciis.A - 10); // 'B' => 66-(65-10)\n if (ch >= asciis.a && ch <= asciis.f) return ch - (asciis.a - 10); // 'b' => 98-(97-10)\n return;\n}\n\n/**\n * Convert hex string to byte array. Uses built-in function, when available.\n * @example hexToBytes('cafe0123') // Uint8Array.from([0xca, 0xfe, 0x01, 0x23])\n */\nexport function hexToBytes(hex: string): Uint8Array {\n if (typeof hex !== 'string') throw new Error('hex string expected, got ' + typeof hex);\n // @ts-ignore\n if (hasHexBuiltin) return Uint8Array.fromHex(hex);\n const hl = hex.length;\n const al = hl / 2;\n if (hl % 2) throw new Error('hex string expected, got unpadded hex of length ' + hl);\n const array = new Uint8Array(al);\n for (let ai = 0, hi = 0; ai < al; ai++, hi += 2) {\n const n1 = asciiToBase16(hex.charCodeAt(hi));\n const n2 = asciiToBase16(hex.charCodeAt(hi + 1));\n if (n1 === undefined || n2 === undefined) {\n const char = hex[hi] + hex[hi + 1];\n throw new Error('hex string expected, got non-hex character \"' + char + '\" at index ' + hi);\n }\n array[ai] = n1 * 16 + n2; // multiply first octet, e.g. 'a3' => 10*16+3 => 160 + 3 => 163\n }\n return array;\n}\n\n/**\n * There is no setImmediate in browser and setTimeout is slow.\n * Call of async fn will return Promise, which will be fullfiled only on\n * next scheduler queue processing step and this is exactly what we need.\n */\nexport const nextTick = async (): Promise<void> => {};\n\n/** Returns control to thread each 'tick' ms to avoid blocking. */\nexport async function asyncLoop(\n iters: number,\n tick: number,\n cb: (i: number) => void\n): Promise<void> {\n let ts = Date.now();\n for (let i = 0; i < iters; i++) {\n cb(i);\n // Date.now() is not monotonic, so in case if clock goes backwards we return return control too\n const diff = Date.now() - ts;\n if (diff >= 0 && diff < tick) continue;\n await nextTick();\n ts += diff;\n }\n}\n\n// Global symbols, but ts doesn't see them: https://github.com/microsoft/TypeScript/issues/31535\ndeclare const TextEncoder: any;\ndeclare const TextDecoder: any;\n\n/**\n * Converts string to bytes using UTF8 encoding.\n * @example utf8ToBytes('abc') // Uint8Array.from([97, 98, 99])\n */\nexport function utf8ToBytes(str: string): Uint8Array {\n if (typeof str !== 'string') throw new Error('string expected');\n return new Uint8Array(new TextEncoder().encode(str)); // https://bugzil.la/1681809\n}\n\n/**\n * Converts bytes to string using UTF8 encoding.\n * @example bytesToUtf8(Uint8Array.from([97, 98, 99])) // 'abc'\n */\nexport function bytesToUtf8(bytes: Uint8Array): string {\n return new TextDecoder().decode(bytes);\n}\n\n/** Accepted input of hash functions. Strings are converted to byte arrays. */\nexport type Input = string | Uint8Array;\n/**\n * Normalizes (non-hex) string or Uint8Array to Uint8Array.\n * Warning: when Uint8Array is passed, it would NOT get copied.\n * Keep in mind for future mutable operations.\n */\nexport function toBytes(data: Input): Uint8Array {\n if (typeof data === 'string') data = utf8ToBytes(data);\n abytes(data);\n return data;\n}\n\n/** KDFs can accept string or Uint8Array for user convenience. */\nexport type KDFInput = string | Uint8Array;\n/**\n * Helper for KDFs: consumes uint8array or string.\n * When string is passed, does utf8 decoding, using TextDecoder.\n */\nexport function kdfInputToBytes(data: KDFInput): Uint8Array {\n if (typeof data === 'string') data = utf8ToBytes(data);\n abytes(data);\n return data;\n}\n\n/** Copies several Uint8Arrays into one. */\nexport function concatBytes(...arrays: Uint8Array[]): Uint8Array {\n let sum = 0;\n for (let i = 0; i < arrays.length; i++) {\n const a = arrays[i];\n abytes(a);\n sum += a.length;\n }\n const res = new Uint8Array(sum);\n for (let i = 0, pad = 0; i < arrays.length; i++) {\n const a = arrays[i];\n res.set(a, pad);\n pad += a.length;\n }\n return res;\n}\n\ntype EmptyObj = {};\nexport function checkOpts<T1 extends EmptyObj, T2 extends EmptyObj>(\n defaults: T1,\n opts?: T2\n): T1 & T2 {\n if (opts !== undefined && {}.toString.call(opts) !== '[object Object]')\n throw new Error('options should be object or undefined');\n const merged = Object.assign(defaults, opts);\n return merged as T1 & T2;\n}\n\n/** Hash interface. */\nexport type IHash = {\n (data: Uint8Array): Uint8Array;\n blockLen: number;\n outputLen: number;\n create: any;\n};\n\n/** For runtime check if class implements interface */\nexport abstract class Hash<T extends Hash<T>> {\n abstract blockLen: number; // Bytes per block\n abstract outputLen: number; // Bytes in output\n abstract update(buf: Input): this;\n // Writes digest into buf\n abstract digestInto(buf: Uint8Array): void;\n abstract digest(): Uint8Array;\n /**\n * Resets internal state. Makes Hash instance unusable.\n * Reset is impossible for keyed hashes if key is consumed into state. If digest is not consumed\n * by user, they will need to manually call `destroy()` when zeroing is necessary.\n */\n abstract destroy(): void;\n /**\n * Clones hash instance. Unsafe: doesn't check whether `to` is valid. Can be used as `clone()`\n * when no options are passed.\n * Reasons to use `_cloneInto` instead of clone: 1) performance 2) reuse instance => all internal\n * buffers are overwritten => causes buffer overwrite which is used for digest in some cases.\n * There are no guarantees for clean-up because it's impossible in JS.\n */\n abstract _cloneInto(to?: T): T;\n // Safe version that clones internal state\n abstract clone(): T;\n}\n\n/**\n * XOF: streaming API to read digest in chunks.\n * Same as 'squeeze' in keccak/k12 and 'seek' in blake3, but more generic name.\n * When hash used in XOF mode it is up to user to call '.destroy' afterwards, since we cannot\n * destroy state, next call can require more bytes.\n */\nexport type HashXOF<T extends Hash<T>> = Hash<T> & {\n xof(bytes: number): Uint8Array; // Read 'bytes' bytes from digest stream\n xofInto(buf: Uint8Array): Uint8Array; // read buf.length bytes from digest stream into buf\n};\n\n/** Hash function */\nexport type CHash = ReturnType<typeof createHasher>;\n/** Hash function with output */\nexport type CHashO = ReturnType<typeof createOptHasher>;\n/** XOF with output */\nexport type CHashXO = ReturnType<typeof createXOFer>;\n\n/** Wraps hash function, creating an interface on top of it */\nexport function createHasher<T extends Hash<T>>(\n hashCons: () => Hash<T>\n): {\n (msg: Input): Uint8Array;\n outputLen: number;\n blockLen: number;\n create(): Hash<T>;\n} {\n const hashC = (msg: Input): Uint8Array => hashCons().update(toBytes(msg)).digest();\n const tmp = hashCons();\n hashC.outputLen = tmp.outputLen;\n hashC.blockLen = tmp.blockLen;\n hashC.create = () => hashCons();\n return hashC;\n}\n\nexport function createOptHasher<H extends Hash<H>, T extends Object>(\n hashCons: (opts?: T) => Hash<H>\n): {\n (msg: Input, opts?: T): Uint8Array;\n outputLen: number;\n blockLen: number;\n create(opts?: T): Hash<H>;\n} {\n const hashC = (msg: Input, opts?: T): Uint8Array => hashCons(opts).update(toBytes(msg)).digest();\n const tmp = hashCons({} as T);\n hashC.outputLen = tmp.outputLen;\n hashC.blockLen = tmp.blockLen;\n hashC.create = (opts?: T) => hashCons(opts);\n return hashC;\n}\n\nexport function createXOFer<H extends HashXOF<H>, T extends Object>(\n hashCons: (opts?: T) => HashXOF<H>\n): {\n (msg: Input, opts?: T): Uint8Array;\n outputLen: number;\n blockLen: number;\n create(opts?: T): HashXOF<H>;\n} {\n const hashC = (msg: Input, opts?: T): Uint8Array => hashCons(opts).update(toBytes(msg)).digest();\n const tmp = hashCons({} as T);\n hashC.outputLen = tmp.outputLen;\n hashC.blockLen = tmp.blockLen;\n hashC.create = (opts?: T) => hashCons(opts);\n return hashC;\n}\nexport const wrapConstructor: typeof createHasher = createHasher;\nexport const wrapConstructorWithOpts: typeof createOptHasher = createOptHasher;\nexport const wrapXOFConstructorWithOpts: typeof createXOFer = createXOFer;\n\n/** Cryptographically secure PRNG. Uses internal OS-level `crypto.getRandomValues`. */\nexport function randomBytes(bytesLength = 32): Uint8Array {\n if (crypto && typeof crypto.getRandomValues === 'function') {\n return crypto.getRandomValues(new Uint8Array(bytesLength));\n }\n // Legacy Node.js compatibility\n if (crypto && typeof crypto.randomBytes === 'function') {\n return Uint8Array.from(crypto.randomBytes(bytesLength));\n }\n throw new Error('crypto.getRandomValues must be defined');\n}\n", "/**\n * Hex, bytes and number utilities.\n * @module\n */\n/*! noble-curves - MIT License (c) 2022 Paul Miller (paulmillr.com) */\n\n// 100 lines of code in the file are duplicated from noble-hashes (utils).\n// This is OK: `abstract` directory does not use noble-hashes.\n// User may opt-in into using different hashing library. This way, noble-hashes\n// won't be included into their bundle.\nconst _0n = /* @__PURE__ */ BigInt(0);\nconst _1n = /* @__PURE__ */ BigInt(1);\nexport type Hex = Uint8Array | string; // hex strings are accepted for simplicity\nexport type PrivKey = Hex | bigint; // bigints are accepted to ease learning curve\nexport type CHash = {\n (message: Uint8Array | string): Uint8Array;\n blockLen: number;\n outputLen: number;\n create(opts?: { dkLen?: number }): any; // For shake\n};\nexport type FHash = (message: Uint8Array | string) => Uint8Array;\n\nexport function isBytes(a: unknown): a is Uint8Array {\n return a instanceof Uint8Array || (ArrayBuffer.isView(a) && a.constructor.name === 'Uint8Array');\n}\n\nexport function abytes(item: unknown): void {\n if (!isBytes(item)) throw new Error('Uint8Array expected');\n}\n\nexport function abool(title: string, value: boolean): void {\n if (typeof value !== 'boolean') throw new Error(title + ' boolean expected, got ' + value);\n}\n\n// Used in weierstrass, der\nexport function numberToHexUnpadded(num: number | bigint): string {\n const hex = num.toString(16);\n return hex.length & 1 ? '0' + hex : hex;\n}\n\nexport function hexToNumber(hex: string): bigint {\n if (typeof hex !== 'string') throw new Error('hex string expected, got ' + typeof hex);\n return hex === '' ? _0n : BigInt('0x' + hex); // Big Endian\n}\n\n// Built-in hex conversion https://caniuse.com/mdn-javascript_builtins_uint8array_fromhex\nconst hasHexBuiltin: boolean =\n // @ts-ignore\n typeof Uint8Array.from([]).toHex === 'function' && typeof Uint8Array.fromHex === 'function';\n\n// Array where index 0xf0 (240) is mapped to string 'f0'\nconst hexes = /* @__PURE__ */ Array.from({ length: 256 }, (_, i) =>\n i.toString(16).padStart(2, '0')\n);\n\n/**\n * Convert byte array to hex string. Uses built-in function, when available.\n * @example bytesToHex(Uint8Array.from([0xca, 0xfe, 0x01, 0x23])) // 'cafe0123'\n */\nexport function bytesToHex(bytes: Uint8Array): string {\n abytes(bytes);\n // @ts-ignore\n if (hasHexBuiltin) return bytes.toHex();\n // pre-caching improves the speed 6x\n let hex = '';\n for (let i = 0; i < bytes.length; i++) {\n hex += hexes[bytes[i]];\n }\n return hex;\n}\n\n// We use optimized technique to convert hex string to byte array\nconst asciis = { _0: 48, _9: 57, A: 65, F: 70, a: 97, f: 102 } as const;\nfunction asciiToBase16(ch: number): number | undefined {\n if (ch >= asciis._0 && ch <= asciis._9) return ch - asciis._0; // '2' => 50-48\n if (ch >= asciis.A && ch <= asciis.F) return ch - (asciis.A - 10); // 'B' => 66-(65-10)\n if (ch >= asciis.a && ch <= asciis.f) return ch - (asciis.a - 10); // 'b' => 98-(97-10)\n return;\n}\n\n/**\n * Convert hex string to byte array. Uses built-in function, when available.\n * @example hexToBytes('cafe0123') // Uint8Array.from([0xca, 0xfe, 0x01, 0x23])\n */\nexport function hexToBytes(hex: string): Uint8Array {\n if (typeof hex !== 'string') throw new Error('hex string expected, got ' + typeof hex);\n // @ts-ignore\n if (hasHexBuiltin) return Uint8Array.fromHex(hex);\n const hl = hex.length;\n const al = hl / 2;\n if (hl % 2) throw new Error('hex string expected, got unpadded hex of length ' + hl);\n const array = new Uint8Array(al);\n for (let ai = 0, hi = 0; ai < al; ai++, hi += 2) {\n const n1 = asciiToBase16(hex.charCodeAt(hi));\n const n2 = asciiToBase16(hex.charCodeAt(hi + 1));\n if (n1 === undefined || n2 === undefined) {\n const char = hex[hi] + hex[hi + 1];\n throw new Error('hex string expected, got non-hex character \"' + char + '\" at index ' + hi);\n }\n array[ai] = n1 * 16 + n2; // multiply first octet, e.g. 'a3' => 10*16+3 => 160 + 3 => 163\n }\n return array;\n}\n\n// BE: Big Endian, LE: Little Endian\nexport function bytesToNumberBE(bytes: Uint8Array): bigint {\n return hexToNumber(bytesToHex(bytes));\n}\nexport function bytesToNumberLE(bytes: Uint8Array): bigint {\n abytes(bytes);\n return hexToNumber(bytesToHex(Uint8Array.from(bytes).reverse()));\n}\n\nexport function numberToBytesBE(n: number | bigint, len: number): Uint8Array {\n return hexToBytes(n.toString(16).padStart(len * 2, '0'));\n}\nexport function numberToBytesLE(n: number | bigint, len: number): Uint8Array {\n return numberToBytesBE(n, len).reverse();\n}\n// Unpadded, rarely used\nexport function numberToVarBytesBE(n: number | bigint): Uint8Array {\n return hexToBytes(numberToHexUnpadded(n));\n}\n\n/**\n * Takes hex string or Uint8Array, converts to Uint8Array.\n * Validates output length.\n * Will throw error for other types.\n * @param title descriptive title for an error e.g. 'private key'\n * @param hex hex string or Uint8Array\n * @param expectedLength optional, will compare to result array's length\n * @returns\n */\nexport function ensureBytes(title: string, hex: Hex, expectedLength?: number): Uint8Array {\n let res: Uint8Array;\n if (typeof hex === 'string') {\n try {\n res = hexToBytes(hex);\n } catch (e) {\n throw new Error(title + ' must be hex string or Uint8Array, cause: ' + e);\n }\n } else if (isBytes(hex)) {\n // Uint8Array.from() instead of hash.slice() because node.js Buffer\n // is instance of Uint8Array, and its slice() creates **mutable** copy\n res = Uint8Array.from(hex);\n } else {\n throw new Error(title + ' must be hex string or Uint8Array');\n }\n const len = res.length;\n if (typeof expectedLength === 'number' && len !== expectedLength)\n throw new Error(title + ' of length ' + expectedLength + ' expected, got ' + len);\n return res;\n}\n\n/**\n * Copies several Uint8Arrays into one.\n */\nexport function concatBytes(...arrays: Uint8Array[]): Uint8Array {\n let sum = 0;\n for (let i = 0; i < arrays.length; i++) {\n const a = arrays[i];\n abytes(a);\n sum += a.length;\n }\n const res = new Uint8Array(sum);\n for (let i = 0, pad = 0; i < arrays.length; i++) {\n const a = arrays[i];\n res.set(a, pad);\n pad += a.length;\n }\n return res;\n}\n\n// Compares 2 u8a-s in kinda constant time\nexport function equalBytes(a: Uint8Array, b: Uint8Array): boolean {\n if (a.length !== b.length) return false;\n let diff = 0;\n for (let i = 0; i < a.length; i++) diff |= a[i] ^ b[i];\n return diff === 0;\n}\n\n// Global symbols in both browsers and Node.js since v11\n// See https://github.com/microsoft/TypeScript/issues/31535\ndeclare const TextEncoder: any;\n\n/**\n * @example utf8ToBytes('abc') // new Uint8Array([97, 98, 99])\n */\nexport function utf8ToBytes(str: string): Uint8Array {\n if (typeof str !== 'string') throw new Error('string expected');\n return new Uint8Array(new TextEncoder().encode(str)); // https://bugzil.la/1681809\n}\n\n// Is positive bigint\nconst isPosBig = (n: bigint) => typeof n === 'bigint' && _0n <= n;\n\nexport function inRange(n: bigint, min: bigint, max: bigint): boolean {\n return isPosBig(n) && isPosBig(min) && isPosBig(max) && min <= n && n < max;\n}\n\n/**\n * Asserts min <= n < max. NOTE: It's < max and not <= max.\n * @example\n * aInRange('x', x, 1n, 256n); // would assume x is in (1n..255n)\n */\nexport function aInRange(title: string, n: bigint, min: bigint, max: bigint): void {\n // Why min <= n < max and not a (min < n < max) OR b (min <= n <= max)?\n // consider P=256n, min=0n, max=P\n // - a for min=0 would require -1: `inRange('x', x, -1n, P)`\n // - b would commonly require subtraction: `inRange('x', x, 0n, P - 1n)`\n // - our way is the cleanest: `inRange('x', x, 0n, P)\n if (!inRange(n, min, max))\n throw new Error('expected valid ' + title + ': ' + min + ' <= n < ' + max + ', got ' + n);\n}\n\n// Bit operations\n\n/**\n * Calculates amount of bits in a bigint.\n * Same as `n.toString(2).length`\n * TODO: merge with nLength in modular\n */\nexport function bitLen(n: bigint): number {\n let len;\n for (len = 0; n > _0n; n >>= _1n, len += 1);\n return len;\n}\n\n/**\n * Gets single bit at position.\n * NOTE: first bit position is 0 (same as arrays)\n * Same as `!!+Array.from(n.toString(2)).reverse()[pos]`\n */\nexport function bitGet(n: bigint, pos: number): bigint {\n return (n >> BigInt(pos)) & _1n;\n}\n\n/**\n * Sets single bit at position.\n */\nexport function bitSet(n: bigint, pos: number, value: boolean): bigint {\n return n | ((value ? _1n : _0n) << BigInt(pos));\n}\n\n/**\n * Calculate mask for N bits. Not using ** operator with bigints because of old engines.\n * Same as BigInt(`0b${Array(i).fill('1').join('')}`)\n */\nexport const bitMask = (n: number): bigint => (_1n << BigInt(n)) - _1n;\n\n// DRBG\n\nconst u8n = (len: number) => new Uint8Array(len); // creates Uint8Array\nconst u8fr = (arr: ArrayLike<number>) => Uint8Array.from(arr); // another shortcut\ntype Pred<T> = (v: Uint8Array) => T | undefined;\n/**\n * Minimal HMAC-DRBG from NIST 800-90 for RFC6979 sigs.\n * @returns function that will call DRBG until 2nd arg returns something meaningful\n * @example\n * const drbg = createHmacDRBG<Key>(32, 32, hmac);\n * drbg(seed, bytesToKey); // bytesToKey must return Key or undefined\n */\nexport function createHmacDrbg<T>(\n hashLen: number,\n qByteLen: number,\n hmacFn: (key: Uint8Array, ...messages: Uint8Array[]) => Uint8Array\n): (seed: Uint8Array, predicate: Pred<T>) => T {\n if (typeof hashLen !== 'number' || hashLen < 2) throw new Error('hashLen must be a number');\n if (typeof qByteLen !== 'number' || qByteLen < 2) throw new Error('qByteLen must be a number');\n if (typeof hmacFn !== 'function') throw new Error('hmacFn must be a function');\n // Step B, Step C: set hashLen to 8*ceil(hlen/8)\n let v = u8n(hashLen); // Minimal non-full-spec HMAC-DRBG from NIST 800-90 for RFC6979 sigs.\n let k = u8n(hashLen); // Steps B and C of RFC6979 3.2: set hashLen, in our case always same\n let i = 0; // Iterations counter, will throw when over 1000\n const reset = () => {\n v.fill(1);\n k.fill(0);\n i = 0;\n };\n const h = (...b: Uint8Array[]) => hmacFn(k, v, ...b); // hmac(k)(v, ...values)\n const reseed = (seed = u8n(0)) => {\n // HMAC-DRBG reseed() function. Steps D-G\n k = h(u8fr([0x00]), seed); // k = hmac(k || v || 0x00 || seed)\n v = h(); // v = hmac(k || v)\n if (seed.length === 0) return;\n k = h(u8fr([0x01]), seed); // k = hmac(k || v || 0x01 || seed)\n v = h(); // v = hmac(k || v)\n };\n const gen = () => {\n // HMAC-DRBG generate() function\n if (i++ >= 1000) throw new Error('drbg: tried 1000 values');\n let len = 0;\n const out: Uint8Array[] = [];\n while (len < qByteLen) {\n v = h();\n const sl = v.slice();\n out.push(sl);\n len += v.length;\n }\n return concatBytes(...out);\n };\n const genUntil = (seed: Uint8Array, pred: Pred<T>): T => {\n reset();\n reseed(seed); // Steps D-G\n let res: T | undefined = undefined; // Step H: grind until k is in [1..n-1]\n while (!(res = pred(gen()))) reseed();\n reset();\n return res;\n };\n return genUntil;\n}\n\n// Validating curves and fields\n\nconst validatorFns = {\n bigint: (val: any): boolean => typeof val === 'bigint',\n function: (val: any): boolean => typeof val === 'function',\n boolean: (val: any): boolean => typeof val === 'boolean',\n string: (val: any): boolean => typeof val === 'string',\n stringOrUint8Array: (val: any): boolean => typeof val === 'string' || isBytes(val),\n isSafeInteger: (val: any): boolean => Number.isSafeInteger(val),\n array: (val: any): boolean => Array.isArray(val),\n field: (val: any, object: any): any => (object as any).Fp.isValid(val),\n hash: (val: any): boolean => typeof val === 'function' && Number.isSafeInteger(val.outputLen),\n} as const;\ntype Validator = keyof typeof validatorFns;\ntype ValMap<T extends Record<string, any>> = { [K in keyof T]?: Validator };\n// type Record<K extends string | number | symbol, T> = { [P in K]: T; }\n\nexport function validateObject<T extends Record<string, any>>(\n object: T,\n validators: ValMap<T>,\n optValidators: ValMap<T> = {}\n): T {\n const checkField = (fieldName: keyof T, type: Validator, isOptional: boolean) => {\n const checkVal = validatorFns[type];\n if (typeof checkVal !== 'function') throw new Error('invalid validator function');\n\n const val = object[fieldName as keyof typeof object];\n if (isOptional && val === undefined) return;\n if (!checkVal(val, object)) {\n throw new Error(\n 'param ' + String(fieldName) + ' is invalid. Expected ' + type + ', got ' + val\n );\n }\n };\n for (const [fieldName, type] of Object.entries(validators)) checkField(fieldName, type!, false);\n for (const [fieldName, type] of Object.entries(optValidators)) checkField(fieldName, type!, true);\n return object;\n}\n// validate type tests\n// const o: { a: number; b: number; c: number } = { a: 1, b: 5, c: 6 };\n// const z0 = validateObject(o, { a: 'isSafeInteger' }, { c: 'bigint' }); // Ok!\n// // Should fail type-check\n// const z1 = validateObject(o, { a: 'tmp' }, { c: 'zz' });\n// const z2 = validateObject(o, { a: 'isSafeInteger' }, { c: 'zz' });\n// const z3 = validateObject(o, { test: 'boolean', z: 'bug' });\n// const z4 = validateObject(o, { a: 'boolean', z: 'bug' });\n\n/**\n * throws not implemented error\n */\nexport const notImplemented = (): never => {\n throw new Error('not implemented');\n};\n\n/**\n * Memoizes (caches) computation result.\n * Uses WeakMap: the value is going auto-cleaned by GC after last reference is removed.\n */\nexport function memoized<T extends object, R, O extends any[]>(\n fn: (arg: T, ...args: O) => R\n): (arg: T, ...args: O) => R {\n const map = new WeakMap<T, R>();\n return (arg: T, ...args: O): R => {\n const val = map.get(arg);\n if (val !== undefined) return val;\n const computed = fn(arg, ...args);\n map.set(arg, computed);\n return computed;\n };\n}\n", "/**\n * Utils for modular division and finite fields.\n * A finite field over 11 is integer number operations `mod 11`.\n * There is no division: it is replaced by modular multiplicative inverse.\n * @module\n */\n/*! noble-curves - MIT License (c) 2022 Paul Miller (paulmillr.com) */\nimport { anumber } from '@noble/hashes/utils';\nimport {\n bitMask,\n bytesToNumberBE,\n bytesToNumberLE,\n ensureBytes,\n numberToBytesBE,\n numberToBytesLE,\n validateObject,\n} from './utils.ts';\n\n// prettier-ignore\nconst _0n = BigInt(0), _1n = BigInt(1), _2n = /* @__PURE__ */ BigInt(2), _3n = /* @__PURE__ */ BigInt(3);\n// prettier-ignore\nconst _4n = /* @__PURE__ */ BigInt(4), _5n = /* @__PURE__ */ BigInt(5), _8n = /* @__PURE__ */ BigInt(8);\n// prettier-ignore\nconst _9n =/* @__PURE__ */ BigInt(9), _16n = /* @__PURE__ */ BigInt(16);\n\n// Calculates a modulo b\nexport function mod(a: bigint, b: bigint): bigint {\n const result = a % b;\n return result >= _0n ? result : b + result;\n}\n/**\n * Efficiently raise num to power and do modular division.\n * Unsafe in some contexts: uses ladder, so can expose bigint bits.\n * TODO: remove.\n * @example\n * pow(2n, 6n, 11n) // 64n % 11n == 9n\n */\nexport function pow(num: bigint, power: bigint, modulo: bigint): bigint {\n if (power < _0n) throw new Error('invalid exponent, negatives unsupported');\n if (modulo <= _0n) throw new Error('invalid modulus');\n if (modulo === _1n) return _0n;\n let res = _1n;\n while (power > _0n) {\n if (power & _1n) res = (res * num) % modulo;\n num = (num * num) % modulo;\n power >>= _1n;\n }\n return res;\n}\n\n/** Does `x^(2^power)` mod p. `pow2(30, 4)` == `30^(2^4)` */\nexport function pow2(x: bigint, power: bigint, modulo: bigint): bigint {\n let res = x;\n while (power-- > _0n) {\n res *= res;\n res %= modulo;\n }\n return res;\n}\n\n/**\n * Inverses number over modulo.\n * Implemented using [Euclidean GCD](https://brilliant.org/wiki/extended-euclidean-algorithm/).\n */\nexport function invert(number: bigint, modulo: bigint): bigint {\n if (number === _0n) throw new Error('invert: expected non-zero number');\n if (modulo <= _0n) throw new Error('invert: expected positive modulus, got ' + modulo);\n // Fermat's little theorem \"CT-like\" version inv(n) = n^(m-2) mod m is 30x slower.\n let a = mod(number, modulo);\n let b = modulo;\n // prettier-ignore\n let x = _0n, y = _1n, u = _1n, v = _0n;\n while (a !== _0n) {\n // JIT applies optimization if those two lines follow each other\n const q = b / a;\n const r = b % a;\n const m = x - u * q;\n const n = y - v * q;\n // prettier-ignore\n b = a, a = r, x = u, y = v, u = m, v = n;\n }\n const gcd = b;\n if (gcd !== _1n) throw new Error('invert: does not exist');\n return mod(x, modulo);\n}\n\n/**\n * Tonelli-Shanks square root search algorithm.\n * 1. https://eprint.iacr.org/2012/685.pdf (page 12)\n * 2. Square Roots from 1; 24, 51, 10 to Dan Shanks\n * @param P field order\n * @returns function that takes field Fp (created from P) and number n\n */\nexport function tonelliShanks(P: bigint): <T>(Fp: IField<T>, n: T) => T {\n // Do expensive precomputation step\n // Step 1: By factoring out powers of 2 from p - 1,\n // find q and s such that p-1 == q*(2^s) with q odd\n let Q = P - _1n;\n let S = 0;\n while (Q % _2n === _0n) {\n Q /= _2n;\n S++;\n }\n\n // Step 2: Select a non-square z such that (z | p) \u2261 -1 and set c \u2261 zq\n let Z = _2n;\n const _Fp = Field(P);\n while (Z < P && FpIsSquare(_Fp, Z)) {\n if (Z++ > 1000) throw new Error('Cannot find square root: probably non-prime P');\n }\n\n // Fast-path\n if (S === 1) {\n const p1div4 = (P + _1n) / _4n;\n return function tonelliFast<T>(Fp: IField<T>, n: T) {\n const root = Fp.pow(n, p1div4);\n if (!Fp.eql(Fp.sqr(root), n)) throw new Error('Cannot find square root');\n return root;\n };\n }\n // Slow-path\n const Q1div2 = (Q + _1n) / _2n;\n return function tonelliSlow<T>(Fp: IField<T>, n: T): T {\n // Step 0: Check that n is indeed a square: (n | p) should not be \u2261 -1\n if (!FpIsSquare(Fp, n)) throw new Error('Cannot find square root');\n let r = S;\n // TODO: test on Fp2 and others\n let g = Fp.pow(Fp.mul(Fp.ONE, Z), Q); // will update both x and b\n let x = Fp.pow(n, Q1div2); // first guess at the square root\n let b = Fp.pow(n, Q); // first guess at the fudge factor\n\n while (!Fp.eql(b, Fp.ONE)) {\n // (4. If t = 0, return r = 0)\n // https://en.wikipedia.org/wiki/Tonelli%E2%80%93Shanks_algorithm\n if (Fp.eql(b, Fp.ZERO)) return Fp.ZERO;\n // Find m such b^(2^m)==1\n let m = 1;\n for (let t2 = Fp.sqr(b); m < r; m++) {\n if (Fp.eql(t2, Fp.ONE)) break;\n t2 = Fp.sqr(t2); // t2 *= t2\n }\n // NOTE: r-m-1 can be bigger than 32, need to convert to bigint before shift,\n // otherwise there will be overflow.\n const ge = Fp.pow(g, _1n << BigInt(r - m - 1)); // ge = 2^(r-m-1)\n g = Fp.sqr(ge); // g = ge * ge\n x = Fp.mul(x, ge); // x *= ge\n b = Fp.mul(b, g); // b *= g\n r = m;\n }\n return x;\n };\n}\n\n/**\n * Square root for a finite field. It will try to check if optimizations are applicable and fall back to 4:\n *\n * 1. P \u2261 3 (mod 4)\n * 2. P \u2261 5 (mod 8)\n * 3. P \u2261 9 (mod 16)\n * 4. Tonelli-Shanks algorithm\n *\n * Different algorithms can give different roots, it is up to user to decide which one they want.\n * For example there is FpSqrtOdd/FpSqrtEven to choice root based on oddness (used for hash-to-curve).\n */\nexport function FpSqrt(P: bigint): <T>(Fp: IField<T>, n: T) => T {\n // P \u2261 3 (mod 4)\n // \u221An = n^((P+1)/4)\n if (P % _4n === _3n) {\n // Not all roots possible!\n // const ORDER =\n // 0x1a0111ea397fe69a4b1ba7b6434bacd764774b84f38512bf6730d2a0f6b0f6241eabfffeb153ffffb9feffffffffaaabn;\n // const NUM = 72057594037927816n;\n return function sqrt3mod4<T>(Fp: IField<T>, n: T) {\n const p1div4 = (P + _1n) / _4n;\n const root = Fp.pow(n, p1div4);\n // Throw if root**2 != n\n if (!Fp.eql(Fp.sqr(root), n)) throw new Error('Cannot find square root');\n return root;\n };\n }\n\n // Atkin algorithm for q \u2261 5 (mod 8), https://eprint.iacr.org/2012/685.pdf (page 10)\n if (P % _8n === _5n) {\n return function sqrt5mod8<T>(Fp: IField<T>, n: T) {\n const n2 = Fp.mul(n, _2n);\n const c1 = (P - _5n) / _8n;\n const v = Fp.pow(n2, c1);\n const nv = Fp.mul(n, v);\n const i = Fp.mul(Fp.mul(nv, _2n), v);\n const root = Fp.mul(nv, Fp.sub(i, Fp.ONE));\n if (!Fp.eql(Fp.sqr(root), n)) throw new Error('Cannot find square root');\n return root;\n };\n }\n\n // P \u2261 9 (mod 16)\n if (P % _16n === _9n) {\n // NOTE: tonelli is too slow for bls-Fp2 calculations even on start\n // Means we cannot use sqrt for constants at all!\n //\n // const c1 = Fp.sqrt(Fp.negate(Fp.ONE)); // 1. c1 = sqrt(-1) in F, i.e., (c1^2) == -1 in F\n // const c2 = Fp.sqrt(c1); // 2. c2 = sqrt(c1) in F, i.e., (c2^2) == c1 in F\n // const c3 = Fp.sqrt(Fp.negate(c1)); // 3. c3 = sqrt(-c1) in F, i.e., (c3^2) == -c1 in F\n // const c4 = (P + _7n) / _16n; // 4. c4 = (q + 7) / 16 # Integer arithmetic\n // sqrt = (x) => {\n // let tv1 = Fp.pow(x, c4); // 1. tv1 = x^c4\n // let tv2 = Fp.mul(c1, tv1); // 2. tv2 = c1 * tv1\n // const tv3 = Fp.mul(c2, tv1); // 3. tv3 = c2 * tv1\n // let tv4 = Fp.mul(c3, tv1); // 4. tv4 = c3 * tv1\n // const e1 = Fp.equals(Fp.square(tv2), x); // 5. e1 = (tv2^2) == x\n // const e2 = Fp.equals(Fp.square(tv3), x); // 6. e2 = (tv3^2) == x\n // tv1 = Fp.cmov(tv1, tv2, e1); // 7. tv1 = CMOV(tv1, tv2, e1) # Select tv2 if (tv2^2) == x\n // tv2 = Fp.cmov(tv4, tv3, e2); // 8. tv2 = CMOV(tv4, tv3, e2) # Select tv3 if (tv3^2) == x\n // const e3 = Fp.equals(Fp.square(tv2), x); // 9. e3 = (tv2^2) == x\n // return Fp.cmov(tv1, tv2, e3); // 10. z = CMOV(tv1, tv2, e3) # Select the sqrt from tv1 and tv2\n // }\n }\n // Other cases: Tonelli-Shanks algorithm\n return tonelliShanks(P);\n}\n\n// Little-endian check for first LE bit (last BE bit);\nexport const isNegativeLE = (num: bigint, modulo: bigint): boolean =>\n (mod(num, modulo) & _1n) === _1n;\n\n/** Field is not always over prime: for example, Fp2 has ORDER(q)=p^m. */\nexport interface IField<T> {\n ORDER: bigint;\n isLE: boolean;\n BYTES: number;\n BITS: number;\n MASK: bigint;\n ZERO: T;\n ONE: T;\n // 1-arg\n create: (num: T) => T;\n isValid: (num: T) => boolean;\n is0: (num: T) => boolean;\n neg(num: T): T;\n inv(num: T): T;\n sqrt(num: T): T;\n sqr(num: T): T;\n // 2-args\n eql(lhs: T, rhs: T): boolean;\n add(lhs: T, rhs: T): T;\n sub(lhs: T, rhs: T): T;\n mul(lhs: T, rhs: T | bigint): T;\n pow(lhs: T, power: bigint): T;\n div(lhs: T, rhs: T | bigint): T;\n // N for NonNormalized (for now)\n addN(lhs: T, rhs: T): T;\n subN(lhs: T, rhs: T): T;\n mulN(lhs: T, rhs: T | bigint): T;\n sqrN(num: T): T;\n\n // Optional\n // Should be same as sgn0 function in\n // [RFC9380](https://www.rfc-editor.org/rfc/rfc9380#section-4.1).\n // NOTE: sgn0 is 'negative in LE', which is same as odd. And negative in LE is kinda strange definition anyway.\n isOdd?(num: T): boolean; // Odd instead of even since we have it for Fp2\n // legendre?(num: T): T;\n pow(lhs: T, power: bigint): T;\n invertBatch: (lst: T[]) => T[];\n toBytes(num: T): Uint8Array;\n fromBytes(bytes: Uint8Array): T;\n // If c is False, CMOV returns a, otherwise it returns b.\n cmov(a: T, b: T, c: boolean): T;\n}\n// prettier-ignore\nconst FIELD_FIELDS = [\n 'create', 'isValid', 'is0', 'neg', 'inv', 'sqrt', 'sqr',\n 'eql', 'add', 'sub', 'mul', 'pow', 'div',\n 'addN', 'subN', 'mulN', 'sqrN'\n] as const;\nexport function validateField<T>(field: IField<T>): IField<T> {\n const initial = {\n ORDER: 'bigint',\n MASK: 'bigint',\n BYTES: 'isSafeInteger',\n BITS: 'isSafeInteger',\n } as Record<string, string>;\n const opts = FIELD_FIELDS.reduce((map, val: string) => {\n map[val] = 'function';\n return map;\n }, initial);\n return validateObject(field, opts);\n}\n\n// Generic field functions\n\n/**\n * Same as `pow` but for Fp: non-constant-time.\n * Unsafe in some contexts: uses ladder, so can expose bigint bits.\n */\nexport function FpPow<T>(Fp: IField<T>, num: T, power: bigint): T {\n if (power < _0n) throw new Error('invalid exponent, negatives unsupported');\n if (power === _0n) return Fp.ONE;\n if (power === _1n) return num;\n // @ts-ignore\n let p = Fp.ONE;\n let d = num;\n while (power > _0n) {\n if (power & _1n) p = Fp.mul(p, d);\n d = Fp.sqr(d);\n power >>= _1n;\n }\n return p;\n}\n\n/**\n * Efficiently invert an array of Field elements.\n * Exception-free. Will return `undefined` for 0 elements.\n * @param passZero map 0 to 0 (instead of undefined)\n */\nexport function FpInvertBatch<T>(Fp: IField<T>, nums: T[], passZero = false): T[] {\n const inverted = new Array(nums.length).fill(passZero ? Fp.ZERO : undefined);\n // Walk from first to last, multiply them by each other MOD p\n const multipliedAcc = nums.reduce((acc, num, i) => {\n if (Fp.is0(num)) return acc;\n inverted[i] = acc;\n return Fp.mul(acc, num);\n }, Fp.ONE);\n // Invert last element\n const invertedAcc = Fp.inv(multipliedAcc);\n // Walk from last to first, multiply them by inverted each other MOD p\n nums.reduceRight((acc, num, i) => {\n if (Fp.is0(num)) return acc;\n inverted[i] = Fp.mul(acc, inverted[i]);\n return Fp.mul(acc, num);\n }, invertedAcc);\n return inverted;\n}\n\n// TODO: remove\nexport function FpDiv<T>(Fp: IField<T>, lhs: T, rhs: T | bigint): T {\n return Fp.mul(lhs, typeof rhs === 'bigint' ? invert(rhs, Fp.ORDER) : Fp.inv(rhs));\n}\n\n/**\n * Legendre symbol.\n * Legendre constant is used to calculate Legendre symbol (a | p)\n * which denotes the value of a^((p-1)/2) (mod p)..\n *\n * * (a | p) \u2261 1 if a is a square (mod p), quadratic residue\n * * (a | p) \u2261 -1 if a is not a square (mod p), quadratic non residue\n * * (a | p) \u2261 0 if a \u2261 0 (mod p)\n */\nexport function FpLegendre<T>(Fp: IField<T>, n: T): number {\n const legc = (Fp.ORDER - _1n) / _2n;\n const powered = Fp.pow(n, legc);\n const yes = Fp.eql(powered, Fp.ONE);\n const zero = Fp.eql(powered, Fp.ZERO);\n const no = Fp.eql(powered, Fp.neg(Fp.ONE));\n if (!yes && !zero && !no) throw new Error('Cannot find square root: probably non-prime P');\n return yes ? 1 : zero ? 0 : -1;\n}\n\n// This function returns True whenever the value x is a square in the field F.\nexport function FpIsSquare<T>(Fp: IField<T>, n: T): boolean {\n const l = FpLegendre(Fp, n);\n return l === 0 || l === 1;\n}\n\n// CURVE.n lengths\nexport function nLength(\n n: bigint,\n nBitLength?: number\n): {\n nBitLength: number;\n nByteLength: number;\n} {\n // Bit size, byte size of CURVE.n\n if (nBitLength !== undefined) anumber(nBitLength);\n const _nBitLength = nBitLength !== undefined ? nBitLength : n.toString(2).length;\n const nByteLength = Math.ceil(_nBitLength / 8);\n return { nBitLength: _nBitLength, nByteLength };\n}\n\ntype FpField = IField<bigint> & Required<Pick<IField<bigint>, 'isOdd'>>;\n/**\n * Initializes a finite field over prime.\n * Major performance optimizations:\n * * a) denormalized operations like mulN instead of mul\n * * b) same object shape: never add or remove keys\n * * c) Object.freeze\n * Fragile: always run a benchmark on a change.\n * Security note: operations don't check 'isValid' for all elements for performance reasons,\n * it is caller responsibility to check this.\n * This is low-level code, please make sure you know what you're doing.\n * @param ORDER prime positive bigint\n * @param bitLen how many bits the field consumes\n * @param isLE (def: false) if encoding / decoding should be in little-endian\n * @param redef optional faster redefinitions of sqrt and other methods\n */\nexport function Field(\n ORDER: bigint,\n bitLen?: number,\n isLE = false,\n redef: Partial<IField<bigint>> = {}\n): Readonly<FpField> {\n if (ORDER <= _0n) throw new Error('invalid field: expected ORDER > 0, got ' + ORDER);\n const { nBitLength: BITS, nByteLength: BYTES } = nLength(ORDER, bitLen);\n if (BYTES > 2048) throw new Error('invalid field: expected ORDER of <= 2048 bytes');\n let sqrtP: ReturnType<typeof FpSqrt>; // cached sqrtP\n const f: Readonly<FpField> = Object.freeze({\n ORDER,\n isLE,\n BITS,\n BYTES,\n MASK: bitMask(BITS),\n ZERO: _0n,\n ONE: _1n,\n create: (num) => mod(num, ORDER),\n isValid: (num) => {\n if (typeof num !== 'bigint')\n throw new Error('invalid field element: expected bigint, got ' + typeof num);\n return _0n <= num && num < ORDER; // 0 is valid element, but it's not invertible\n },\n is0: (num) => num === _0n,\n isOdd: (num) => (num & _1n) === _1n,\n neg: (num) => mod(-num, ORDER),\n eql: (lhs, rhs) => lhs === rhs,\n\n sqr: (num) => mod(num * num, ORDER),\n add: (lhs, rhs) => mod(lhs + rhs, ORDER),\n sub: (lhs, rhs) => mod(lhs - rhs, ORDER),\n mul: (lhs, rhs) => mod(lhs * rhs, ORDER),\n pow: (num, power) => FpPow(f, num, power),\n div: (lhs, rhs) => mod(lhs * invert(rhs, ORDER), ORDER),\n\n // Same as above, but doesn't normalize\n sqrN: (num) => num * num,\n addN: (lhs, rhs) => lhs + rhs,\n subN: (lhs, rhs) => lhs - rhs,\n mulN: (lhs, rhs) => lhs * rhs,\n\n inv: (num) => invert(num, ORDER),\n sqrt:\n redef.sqrt ||\n ((n) => {\n if (!sqrtP) sqrtP = FpSqrt(ORDER);\n return sqrtP(f, n);\n }),\n toBytes: (num) => (isLE ? numberToBytesLE(num, BYTES) : numberToBytesBE(num, BYTES)),\n fromBytes: (bytes) => {\n if (bytes.length !== BYTES)\n throw new Error('Field.fromBytes: expected ' + BYTES + ' bytes, got ' + bytes.length);\n return isLE ? bytesToNumberLE(bytes) : bytesToNumberBE(bytes);\n },\n // TODO: we don't need it here, move out to separate fn\n invertBatch: (lst) => FpInvertBatch(f, lst),\n // We can't move this out because Fp6, Fp12 implement it\n // and it's unclear what to return in there.\n cmov: (a, b, c) => (c ? b : a),\n } as FpField);\n return Object.freeze(f);\n}\n\nexport function FpSqrtOdd<T>(Fp: IField<T>, elm: T): T {\n if (!Fp.isOdd) throw new Error(\"Field doesn't have isOdd\");\n const root = Fp.sqrt(elm);\n return Fp.isOdd(root) ? root : Fp.neg(root);\n}\n\nexport function FpSqrtEven<T>(Fp: IField<T>, elm: T): T {\n if (!Fp.isOdd) throw new Error(\"Field doesn't have isOdd\");\n const root = Fp.sqrt(elm);\n return Fp.isOdd(root) ? Fp.neg(root) : root;\n}\n\n/**\n * \"Constant-time\" private key generation utility.\n * Same as mapKeyToField, but accepts less bytes (40 instead of 48 for 32-byte field).\n * Which makes it slightly more biased, less secure.\n * @deprecated use `mapKeyToField` instead\n */\nexport function hashToPrivateScalar(\n hash: string | Uint8Array,\n groupOrder: bigint,\n isLE = false\n): bigint {\n hash = ensureBytes('privateHash', hash);\n const hashLen = hash.length;\n const minLen = nLength(groupOrder).nByteLength + 8;\n if (minLen < 24 || hashLen < minLen || hashLen > 1024)\n throw new Error(\n 'hashToPrivateScalar: expected ' + minLen + '-1024 bytes of input, got ' + hashLen\n );\n const num = isLE ? bytesToNumberLE(hash) : bytesToNumberBE(hash);\n return mod(num, groupOrder - _1n) + _1n;\n}\n\n/**\n * Returns total number of bytes consumed by the field element.\n * For example, 32 bytes for usual 256-bit weierstrass curve.\n * @param fieldOrder number of field elements, usually CURVE.n\n * @returns byte length of field\n */\nexport function getFieldBytesLength(fieldOrder: bigint): number {\n if (typeof fieldOrder !== 'bigint') throw new Error('field order must be bigint');\n const bitLength = fieldOrder.toString(2).length;\n return Math.ceil(bitLength / 8);\n}\n\n/**\n * Returns minimal amount of bytes that can be safely reduced\n * by field order.\n * Should be 2^-128 for 128-bit curve such as P256.\n * @param fieldOrder number of field elements, usually CURVE.n\n * @returns byte length of target hash\n */\nexport function getMinHashLength(fieldOrder: bigint): number {\n const length = getFieldBytesLength(fieldOrder);\n return length + Math.ceil(length / 2);\n}\n\n/**\n * \"Constant-time\" private key generation utility.\n * Can take (n + n/2) or more bytes of uniform input e.g. from CSPRNG or KDF\n * and convert them into private scalar, with the modulo bias being negligible.