Circles and Crosses » Uncategorized http://ox.no Håvard Stranden's website Sat, 20 Aug 2011 00:11:11 +0000 en hourly 1 http://wordpress.org/?v=3.3.1 Diffie-Hellman support in Node.js http://ox.no/posts/diffie-hellman-support-in-node-js http://ox.no/posts/diffie-hellman-support-in-node-js#comments Tue, 10 May 2011 11:43:07 +0000 Håvard http://ox.no/?p=302 Continue reading →]]> Yay! My patch implementing support for Diffie-Hellman key exchange in Node.js has finally been merged into the Node.js master branch. This will simplify the OpenID for Node.js codebase a lot. It will also make the OpenID association phase run a lot faster, since the current code does Diffie-Hellman in Javascript while the Node.js crypto version does it all in native code using OpenSSL.

A brief API overview:

  • crypto.createDiffieHellman(prime_length)
    • Creates a Diffie-Hellman key exchange object and generates a prime of the given bit length. The generator used is 2.
  • crypto.createDiffieHellman(prime, encoding='binary')
    • Creates a Diffie-Hellman key exchange object using the supplied prime. The generator used is 2. Encoding can be 'binary', 'hex', or 'base64'.
  • diffieHellman.generateKeys(encoding='binary')
    • Generates private and public Diffie-Hellman key values, and returns the public key in the specified encoding. This key should be transferred to the other party. Encoding can be 'binary', 'hex', or 'base64'.
  • diffieHellman.computeSecret(other_public_key, input_encoding='binary', output_encoding=input_encoding)
    • Computes the shared secret using other_public_key as the other party’s public key and returns the computed shared secret. Supplied key is interpreted using specified input_encoding, and secret is encoded using specified output_encoding. Encodings can be 'binary', 'hex', or 'base64'. If no output encoding is given, the input encoding is used as output encoding.
  • diffieHellman.getPrime(encoding='binary')
    • Returns the Diffie-Hellman prime in the specified encoding, which can be 'binary', 'hex', or 'base64'.
  • diffieHellman.getGenerator(encoding='binary')
    • Returns the Diffie-Hellman prime in the specified encoding, which can be 'binary', 'hex', or 'base64'.
  • diffieHellman.getPublicKey(encoding='binary')
    • Returns the Diffie-Hellman public key in the specified encoding, which can be 'binary', 'hex', or 'base64'.
  • diffieHellman.getPrivateKey(encoding='binary')
    • Returns the Diffie-Hellman private key in the specified encoding, which can be 'binary', 'hex', or 'base64'.
  • diffieHellman.setPublicKey(public_key, encoding='binary')
    • Sets the Diffie-Hellman public key. Key encoding can be 'binary', 'hex', or 'base64'.
  • diffieHellman.setPrivateKey(public_key, encoding='binary')
    • Sets the Diffie-Hellman private key. Key encoding can be 'binary', 'hex', or 'base64'.

NOTE: The API is still subject to change.

I would appreciate getting a note if you actually do something useful with it. :) Play around with it and let me know what you think!

]]> http://ox.no/posts/diffie-hellman-support-in-node-js/feed 0 A Software Craftsmans Bookshelf http://ox.no/posts/a-software-craftsmans-bookshelf http://ox.no/posts/a-software-craftsmans-bookshelf#comments Thu, 06 May 2010 09:50:31 +0000 Håvard http://ox.no/?p=108 Continue reading →]]> A (long) while ago, Gøran Hansen tagged me and invited me to share a set of recommended books. Reorganizing my book shelves, the tag came back to mind, and I decided to name a few of the books that I have learned from. The first three are essential, the rest are great books you should read.

]]> http://ox.no/posts/a-software-craftsmans-bookshelf/feed 2