ChaoCipher

ChaoCipher is a Ruby implementation of the Chaocipher cipher, invented by J. F. Byrne; the algorithm was disclosed in 2010, hence this small bit of code!

The Algorithm

You can find more about the Chaocipher at Wikipedia/Chaocipher, and you can read the online PDF which contains details about the algorithm itself, upon which this code is based. The algorithm isn't that involved and is actually quite rudimentary.

How do I use this thing?

To install from RubyGems:

gem install chaocipher

To get the source:

git clone https://github.com/aprescott/chaocipher.git

To run the tests with the source:

rake test

To contribute:

• Fork it
• Make a new feature branch: git checkout -b some-new-thing master
• Hack away and add tests
• Pull request

Basic usage

The Chaocipher works off two alphabets, a "left" and a "right" alphabet which are used for look-up during ciphering and deciphering. The initial two alphabets are all that is required to have a working cipher. For more details, it's probably best that you just read the PDF linked above.

require "chaocipher"

ciphertext_alphabet = "HXUCZVAMDSLKPEFJRIGTWOBNYQ"
plaintext_alphabet = "PTLNBQDEOYSFAVZKGJRIHWXUMC"

cipher = ChaoCipher::Cipher.new(ciphertext_alphabet, plaintext_alphabet)

cipher.encrypt("WELLDONEISBETTERTHANWELLSAID") #=> "OAHQHCNYNXTSZJRRHJBYHQKSOUJY"

Cryptographic security

I have no idea what the strength of this cipher is, so I wouldn't encrypt anything of utter importance with it, personally.