Bletchley Park is a python implementation of an encrypting/decrypting/cracking library for historical ciphers like Caesar shift cipher, substitution cipher, Vigenère cipher and transposition cipher. Only czech language is supported right now.

Why Bletchley Park? It's the place where ciphers and codes of several Axis countries were decrypted, most importantly the ciphers generated by the German Enigma and Lorenz machines.

You will need Python 2.7. Installation using git:

$ git clone git@github.com:havrlant/bletchley-park.git
$ cd bletchley-park
$ sudo python setup.py install
$ bletchleypark -h

Or simply download the zip file instead of cloning from GitHub.

See bletchleypark -h. Supported ciphers are:

• caesar for Caesar/Shift cipher. Key has to be only one letter.
• vig for Vigenère cipher. Key can be arbitrary word, i.e. [a-b]+.
• subs for Substitution cipher; only encrypt/decrypt methods, no cracking method yet. Key has to be permutation of alphabet, for example camntwqzipryofxkhdlusbevjg.
• trans for Transposition cipher. Key can be arbitrary word, i.e. [a-b]+.

If you want to encrypt a text "Hello World" using Caesar (Shift) cipher and the "b" key:

$ bletchleypark -t "Hello World" -e caesar -k b
ifmmpxpsme

To decrypt back to "Hello World" use:

$ bletchleypark -t "ifmmpxpsme" -d caesar -k b
helloworld

If you want to crack a text "..." which was encrypted by Vigenère cipher:

$ bletchleypark -c vig -t "..."

Or you can always use -i file option instead of -t. The file must be in utf-8. Use --charset option otherwise:

$ bletchleypark -c vig -i path/to/file.txt --charset cp1250