This is a feistel cipher implementation I wrote for a Computerphile video. While I started with this being a simple couple of functions, I realised that if I wanted proper file IO, I needed to code up ...

usage: main.py [-h] [--encrypt] [--decrypt] [--crack] [--generate] {caesar,rsa,elgamal,massey,simple,feistel,vigenere} ... Encrypt, decrypt or crack a cipher text ...