104 lines
2.2 KiB
JavaScript
104 lines
2.2 KiB
JavaScript
/*!
|
|
* pbkdf2.js - pbkdf2 for bcoin
|
|
* Copyright (c) 2014-2017, Christopher Jeffrey (MIT License).
|
|
* https://github.com/bcoin-org/bcoin
|
|
*/
|
|
|
|
'use strict';
|
|
|
|
/**
|
|
* @module crypto.pbkdf2-browser
|
|
* @ignore
|
|
*/
|
|
|
|
var digest = require('./digest');
|
|
var crypto = global.crypto || global.msCrypto || {};
|
|
var subtle = crypto.subtle || {};
|
|
|
|
/**
|
|
* Perform key derivation using PBKDF2.
|
|
* @param {Buffer} key
|
|
* @param {Buffer} salt
|
|
* @param {Number} iter
|
|
* @param {Number} len
|
|
* @param {String} alg
|
|
* @returns {Buffer}
|
|
*/
|
|
|
|
exports.derive = function derive(key, salt, iter, len, alg) {
|
|
var size = digest.hash(alg, Buffer.alloc(0)).length;
|
|
var blocks = Math.ceil(len / size);
|
|
var out = Buffer.allocUnsafe(len);
|
|
var buf = Buffer.allocUnsafe(salt.length + 4);
|
|
var block = Buffer.allocUnsafe(size);
|
|
var pos = 0;
|
|
var i, j, k, mac;
|
|
|
|
salt.copy(buf, 0);
|
|
|
|
for (i = 0; i < blocks; i++) {
|
|
buf.writeUInt32BE(i + 1, salt.length, true);
|
|
mac = digest.hmac(alg, buf, key);
|
|
mac.copy(block, 0);
|
|
for (j = 1; j < iter; j++) {
|
|
mac = digest.hmac(alg, mac, key);
|
|
for (k = 0; k < size; k++)
|
|
block[k] ^= mac[k];
|
|
}
|
|
block.copy(out, pos);
|
|
pos += size;
|
|
}
|
|
|
|
return out;
|
|
};
|
|
|
|
/**
|
|
* Execute pbkdf2 asynchronously.
|
|
* @param {Buffer} key
|
|
* @param {Buffer} salt
|
|
* @param {Number} iter
|
|
* @param {Number} len
|
|
* @param {String} alg
|
|
* @returns {Promise}
|
|
*/
|
|
|
|
exports.deriveAsync = async function deriveAsync(key, salt, iter, len, alg) {
|
|
var algo = { name: 'PBKDF2' };
|
|
var use = ['deriveBits'];
|
|
var options, imported, data;
|
|
|
|
if (!subtle.importKey || !subtle.deriveBits)
|
|
return exports.derive(key, salt, iter, len, alg);
|
|
|
|
options = {
|
|
name: 'PBKDF2',
|
|
salt: salt,
|
|
iterations: iter,
|
|
hash: getHash(alg)
|
|
};
|
|
|
|
imported = await subtle.importKey('raw', key, algo, false, use);
|
|
data = await subtle.deriveBits(options, imported, len * 8);
|
|
|
|
return Buffer.from(data);
|
|
};
|
|
|
|
/*
|
|
* Helpers
|
|
*/
|
|
|
|
function getHash(name) {
|
|
switch (name) {
|
|
case 'sha1':
|
|
return 'SHA-1';
|
|
case 'sha256':
|
|
return 'SHA-256';
|
|
case 'sha384':
|
|
return 'SHA-384';
|
|
case 'sha512':
|
|
return 'SHA-512';
|
|
default:
|
|
throw new Error('Algorithm not supported: ' + name);
|
|
}
|
|
}
|