skein

Compact and fast 512-bit encryption add-on for node.js using Skein hash functions.

What is Skein?

Skein is a family of cryptographic hash functions. Skein’s design combines speed, security, simplicity, and a great deal of flexibility in a modular package that is easy to analyze. [1]

What is skein add-on?

Skein add-on wraps original Skein C implementation. The add-on makes Skein available for node.js packages without sacrificing its speed. The wrapper includes a 512-bit hash function and a pair of 512-bit symmetric encryption functions.

Status

The add-on is currently available for Linux, OS X and Windows platforms. Raspbian build is in progress and it will be available soon. Please stay tuned and check out this page for further news.

How do I install?

npm install skein

skein functions

The following functions are currently available from the skein add-on. These functions are asynchronous in nature and conforms to node.js 'error-first' callback convention. Argument errors can cause exceptions to be thrown.

calcHash

The method calcHash takes a string argument and returns a 512-bit (64-byte) hash value in a Buffer object. The Buffer object is NOT stored internally. The Buffer object can be used as a key in the encrypt and decrypt functions.

var skein = require('skein');
var crypto = new skein.Crypto();
crypto.calcHash("my top secret password", function (err, hash) {
   assert.equal(err, null);
   assert.equal(hash.length, 64);
});

encrypt

The method encrypt takes a 64-byte hash value as a key, a String object to encrypt, and a function object to return encrypted binary data in a Buffer object. Typically the hash value is calculated using the calcHash function although it does not have to be.

var skein = require('skein');
var crypto = new skein.Crypto();
crypto.calcHash("my top secret password", function (err, hash) {
   assert.equal(err, null);
   assert.equal(hash.length, 64);
   var text = "Οὐχὶ ταὐτὰ παρίσταταί μοι γιγνώσκειν";
   crypto.encrypt(hash, text, function (err, encrypted) {
      assert.equal(err, null);
      assert.equal(encrypted.length, 76);
      done();
   });
});

decrypt

The method decrypt takes a 64-byte hash value as a key, a binary Buffer object to decrypt, and a function object to return decrypted data in a String object. Typically the hash value is calculated using the calcHash function although it does not have to be.

var skein = require('skein');
var crypto = new skein.Crypto();
crypto.calcHash("my top secret password", function (err, hash) {
   assert.equal(err, null);
   assert.equal(hash.length, 64);
   var text = "Οὐχὶ ταὐτὰ παρίσταταί μοι γιγνώσκειν";
   crypto.encrypt(hash, text, function (err, encrypted) {
      assert.equal(err, null);
      crypto.decrypt(hash, encrypted, function (err, decrypted) {
         assert.equal(err, null);
         assert.equal(decrypted, text);
         done();
      });
   });
});

Acknowledgement

Skein was developed by Niels Ferguson, Stefan Lucks, Bruce Schneier, Doug Whiting, Mihir Bellare, Tadayoshi Kohno, Jon Callas, Jesse Walker.

Reference

1 Skein website