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@noble/hashes

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Audited & minimal 0-dependency JS implementation of SHA, RIPEMD, BLAKE, HMAC, HKDF, PBKDF & Scrypt

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/** * Utilities for hex, bytes, CSPRNG. * @module */ /*! noble-hashes - MIT License (c) 2022 Paul Miller (paulmillr.com) */ /** Checks if something is Uint8Array. Be careful: nodejs Buffer will return true. */ export function isBytes(a) { return a instanceof Uint8Array || (ArrayBuffer.isView(a) && a.constructor.name === 'Uint8Array'); } /** Asserts something is positive integer. */ export function anumber(n, title = '') { if (!Number.isSafeInteger(n) || n < 0) { const prefix = title && `"${title}" `; throw new Error(`${prefix}expected integer >0, got ${n}`); } } /** Asserts something is Uint8Array. */ export function abytes(value, length, title = '') { const bytes = isBytes(value); const len = value?.length; const needsLen = length !== undefined; if (!bytes || (needsLen && len !== length)) { const prefix = title && `"${title}" `; const ofLen = needsLen ? ` of length ${length}` : ''; const got = bytes ? `length=${len}` : `type=${typeof value}`; throw new Error(prefix + 'expected Uint8Array' + ofLen + ', got ' + got); } return value; } /** Asserts something is hash */ export function ahash(h) { if (typeof h !== 'function' || typeof h.create !== 'function') throw new Error('Hash must wrapped by utils.createHasher'); anumber(h.outputLen); anumber(h.blockLen); } /** Asserts a hash instance has not been destroyed / finished */ export function aexists(instance, checkFinished = true) { if (instance.destroyed) throw new Error('Hash instance has been destroyed'); if (checkFinished && instance.finished) throw new Error('Hash#digest() has already been called'); } /** Asserts output is properly-sized byte array */ export function aoutput(out, instance) { abytes(out, undefined, 'digestInto() output'); const min = instance.outputLen; if (out.length < min) { throw new Error('"digestInto() output" expected to be of length >=' + min); } } /** Cast u8 / u16 / u32 to u8. */ export function u8(arr) { return new Uint8Array(arr.buffer, arr.byteOffset, arr.byteLength); } /** Cast u8 / u16 / u32 to u32. */ export function u32(arr) { return new Uint32Array(arr.buffer, arr.byteOffset, Math.floor(arr.byteLength / 4)); } /** Zeroize a byte array. Warning: JS provides no guarantees. */ export function clean(...arrays) { for (let i = 0; i < arrays.length; i++) { arrays[i].fill(0); } } /** Create DataView of an array for easy byte-level manipulation. */ export function createView(arr) { return new DataView(arr.buffer, arr.byteOffset, arr.byteLength); } /** The rotate right (circular right shift) operation for uint32 */ export function rotr(word, shift) { return (word << (32 - shift)) | (word >>> shift); } /** The rotate left (circular left shift) operation for uint32 */ export function rotl(word, shift) { return (word << shift) | ((word >>> (32 - shift)) >>> 0); } /** Is current platform little-endian? Most are. Big-Endian platform: IBM */ export const isLE = /* @__PURE__ */ (() => new Uint8Array(new Uint32Array([0x11223344]).buffer)[0] === 0x44)(); /** The byte swap operation for uint32 */ export function byteSwap(word) { return (((word << 24) & 0xff000000) | ((word << 8) & 0xff0000) | ((word >>> 8) & 0xff00) | ((word >>> 24) & 0xff)); } /** Conditionally byte swap if on a big-endian platform */ export const swap8IfBE = isLE ? (n) => n : (n) => byteSwap(n); /** In place byte swap for Uint32Array */ export function byteSwap32(arr) { for (let i = 0; i < arr.length; i++) { arr[i] = byteSwap(arr[i]); } return arr; } export const swap32IfBE = isLE ? (u) => u : byteSwap32; // Built-in hex conversion https://caniuse.com/mdn-javascript_builtins_uint8array_fromhex const hasHexBuiltin = /* @__PURE__ */ (() => // @ts-ignore typeof Uint8Array.from([]).toHex === 'function' && typeof Uint8Array.fromHex === 'function')(); // Array where index 0xf0 (240) is mapped to string 'f0' const hexes = /* @__PURE__ */ Array.from({ length: 256 }, (_, i) => i.toString(16).padStart(2, '0')); /** * Convert byte array to hex string. Uses built-in function, when available. * @example bytesToHex(Uint8Array.from([0xca, 0xfe, 0x01, 0x23])) // 'cafe0123' */ export function bytesToHex(bytes) { abytes(bytes); // @ts-ignore if (hasHexBuiltin) return bytes.toHex(); // pre-caching improves the speed 6x let hex = ''; for (let i = 0; i < bytes.length; i++) { hex += hexes[bytes[i]]; } return hex; } // 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; } /** * Convert hex string to byte array. Uses built-in function, when available. * @example hexToBytes('cafe0123') // Uint8Array.from([0xca, 0xfe, 0x01, 0x23]) */ export function hexToBytes(hex) { if (typeof hex !== 'string') throw new Error('hex string expected, got ' + typeof hex); // @ts-ignore if (hasHexBuiltin) return Uint8Array.fromHex(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; } /** * There is no setImmediate in browser and setTimeout is slow. * Call of async fn will return Promise, which will be fullfiled only on * next scheduler queue processing step and this is exactly what we need. */ export const nextTick = async () => { }; /** Returns control to thread each 'tick' ms to avoid blocking. */ export async function asyncLoop(iters, tick, cb) { let ts = Date.now(); for (let i = 0; i < iters; i++) { cb(i); // Date.now() is not monotonic, so in case if clock goes backwards we return return control too const diff = Date.now() - ts; if (diff >= 0 && diff < tick) continue; await nextTick(); ts += diff; } } /** * Converts string to bytes using UTF8 encoding. * Built-in doesn't validate input to be string: we do the check. * @example utf8ToBytes('abc') // Uint8Array.from([97, 98, 99]) */ export function utf8ToBytes(str) { if (typeof str !== 'string') throw new Error('string expected'); return new Uint8Array(new TextEncoder().encode(str)); // https://bugzil.la/1681809 } /** * Helper for KDFs: consumes uint8array or string. * When string is passed, does utf8 decoding, using TextDecoder. */ export function kdfInputToBytes(data, errorTitle = '') { if (typeof data === 'string') return utf8ToBytes(data); return abytes(data, undefined, errorTitle); } /** Copies several Uint8Arrays into one. */ export 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; } /** Merges default options and passed options. */ export function checkOpts(defaults, opts) { if (opts !== undefined && {}.toString.call(opts) !== '[object Object]') throw new Error('options must be object or undefined'); const merged = Object.assign(defaults, opts); return merged; } /** Creates function with outputLen, blockLen, create properties from a class constructor. */ export function createHasher(hashCons, info = {}) { const hashC = (msg, opts) => hashCons(opts).update(msg).digest(); const tmp = hashCons(undefined); hashC.outputLen = tmp.outputLen; hashC.blockLen = tmp.blockLen; hashC.create = (opts) => hashCons(opts); Object.assign(hashC, info); return Object.freeze(hashC); } /** Cryptographically secure PRNG. Uses internal OS-level `crypto.getRandomValues`. */ export function randomBytes(bytesLength = 32) { const cr = typeof globalThis === 'object' ? globalThis.crypto : null; if (typeof cr?.getRandomValues !== 'function') throw new Error('crypto.getRandomValues must be defined'); return cr.getRandomValues(new Uint8Array(bytesLength)); } /** Creates OID opts for NIST hashes, with prefix 06 09 60 86 48 01 65 03 04 02. */ export const oidNist = (suffix) => ({ oid: Uint8Array.from([0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, suffix]), }); //# sourceMappingURL=utils.js.map