pbkdf2-sha256

pbkdf2-sha256 is a JavaScript implementation of PBKDF2 using the SHA256 HMAC. It's useful as the Scrypt algorithm uses this. It's fully compatible with Node.js and the browser (via Browserify).

Package Info

• github: https://github.com/cryptocoinjs/pbkdf2-sha256
• tests: https://github.com/cryptocoinjs/pbkdf2-sha256/tree/master/test
• issues: https://github.com/cryptocoinjs/pbkdf2-sha256/issues
• license: BSD
• versioning: http://semver-ftw.org

Why?

This is useful for the Scrypt algorithm.

Why not just use the Node.js pbkdf2 function? The Node.js pbkdf2 function uses the sha1 algorithm and not the sha256 algorithm for its pseudorandom function. This will change when Node v0.12 is released. Until then, this is the next best option.

Installation

npm install --save pbkdf2-sha256

Example

var pbkdf2 = require('pbkdf2-sha256')

var key = 'passwd'
var salt = 'salt'
var res = pbkdf2(key, salt, 1, 64);
console.log(res.toString('hex')) // => 55ac046e56e3089fec1691c22544b605f94185216dde0465e68b9d57c20dacbc49ca9cccf179b645991664b39d77ef317c71b845b1e30bd509112041d3a19783

API

pbkdf2(key, salt, iterations, keyLenBytes)

• key: The key to pass. Either string or Buffer.
• salt: The salt to pass. Either string or Buffer.
• iterations: The number of iterations. Should be type number (integer).
• keyLenBytes: The size of the result in bytes. Type number (integer).

Returns Buffer.

Misc

Alternative Implementations

• https://github.com/bitwiseshiftleft/sjcl/blob/master/core/pbkdf2.js (Stanford JavaScript Crypto Library)
• https://code.google.com/p/crypto-js/source/browse/tags/3.1.2/src/pbkdf2.js (CryptoJS)

Why didn't I use either one of these? They're not Node.js optimized. They also don't use native types, so they'll be slower in the browser.