crypto-pbkdf2

crypto-PBKDF2
=============

crypto.js' PBKDF2 standalone implementation for npm.

Usage (based on Stack Exchange's PBKDF2 implementation):
``js
var CryptoJS = require("crypto-PBKDF2");

var DEFAULT_HASH_ITERATIONS = 4000;

var SALT_SIZE: 192/8;

var KEY_SIZE = 768/32;

/**
* Convenience wrapper around CryptoJS.lib.WordArray.random to grab a new salt value.
* Treat this value as opaque, as it captures iterations.
*
* @param {number} explicitIterations An integer
* @return {string} Return iterations and salt together as one string ({hex-iterations}.{base64-salt})
*/
function generateSalt(explicitIterations){
var defaultHashIterations = DEFAULT_HASH_ITERATIONS;

if(explicitIterations !== null && explicitIterations !== undefined){
// make sure explicitIterations is an integer
if( parseInt(explicitIterations, 10) === explicitIterations ){
throw new Error("explicitIterations must be an integer");
}
// and that it is smaller than our default hash iterations
if( explicitIterations < DEFAULT_HASH_ITERATIONS){
throw new Error("explicitIterations cannot be less than " + DEFAULT_HASH_ITERATIONS);
}
}

// get some random bytes
var bytes = CryptoJS.lib.WordArray.random(SALT_SIZE);

// convert iterations to Hexadecimal
var iterations = (explicitIterations || defaultHashIterations).toString(16);

// concat the iterations and random bytes together.
return iterations + "." + bytes.toString(CryptoJS.enc.Base64);
}

function hashPassword( value, salt ){
var i = salt.indexOf(".");
var iters = parseInt(salt.substring(0, i), 16);
var key = CryptoJS.PBKDF2(value, salt, { "keySize": KEY_SIZE, "iterations": iters });

return key.toString(CryptoJS.enc.Base64);
}

function checkPassword(candidate, salt, hashed){
return hashPassword( candidate, salt ) === hashed;
}

/ Save BOTH the salt and the hashedPassword to your database so you can validate the password later /
var salt = generateSalt();
var hashedPassword = hashPassword( "password", salt );
var isPassword = checkPassword( "password", salt, hashedPassword ); // true
``