Files
heros/node_modules/crypto-es/lib/evpkdf.js
2024-07-17 16:14:14 +08:00

112 lines
2.7 KiB
JavaScript

import {
Base,
WordArray,
} from './core.js';
import { MD5Algo } from './md5.js';
/**
* This key derivation function is meant to conform with EVP_BytesToKey.
* www.openssl.org/docs/crypto/EVP_BytesToKey.html
*/
export class EvpKDFAlgo extends Base {
/**
* Initializes a newly created key derivation function.
*
* @param {Object} cfg (Optional) The configuration options to use for the derivation.
*
* @example
*
* const kdf = CryptoJS.algo.EvpKDF.create();
* const kdf = CryptoJS.algo.EvpKDF.create({ keySize: 8 });
* const kdf = CryptoJS.algo.EvpKDF.create({ keySize: 8, iterations: 1000 });
*/
constructor(cfg) {
super();
/**
* Configuration options.
*
* @property {number} keySize The key size in words to generate. Default: 4 (128 bits)
* @property {Hasher} hasher The hash algorithm to use. Default: MD5
* @property {number} iterations The number of iterations to perform. Default: 1
*/
this.cfg = Object.assign(
new Base(),
{
keySize: 128 / 32,
hasher: MD5Algo,
iterations: 1,
},
cfg,
);
}
/**
* Derives a key from a password.
*
* @param {WordArray|string} password The password.
* @param {WordArray|string} salt A salt.
*
* @return {WordArray} The derived key.
*
* @example
*
* const key = kdf.compute(password, salt);
*/
compute(password, salt) {
let block;
// Shortcut
const { cfg } = this;
// Init hasher
const hasher = cfg.hasher.create();
// Initial values
const derivedKey = WordArray.create();
// Shortcuts
const derivedKeyWords = derivedKey.words;
const { keySize, iterations } = cfg;
// Generate key
while (derivedKeyWords.length < keySize) {
if (block) {
hasher.update(block);
}
block = hasher.update(password).finalize(salt);
hasher.reset();
// Iterations
for (let i = 1; i < iterations; i += 1) {
block = hasher.finalize(block);
hasher.reset();
}
derivedKey.concat(block);
}
derivedKey.sigBytes = keySize * 4;
return derivedKey;
}
}
/**
* Derives a key from a password.
*
* @param {WordArray|string} password The password.
* @param {WordArray|string} salt A salt.
* @param {Object} cfg (Optional) The configuration options to use for this computation.
*
* @return {WordArray} The derived key.
*
* @static
*
* @example
*
* var key = CryptoJS.EvpKDF(password, salt);
* var key = CryptoJS.EvpKDF(password, salt, { keySize: 8 });
* var key = CryptoJS.EvpKDF(password, salt, { keySize: 8, iterations: 1000 });
*/
export const EvpKDF = (password, salt, cfg) => EvpKDFAlgo.create(cfg).compute(password, salt);