affine-chiper is An implementation of the historycal affine chiper written in C and a Brute Force Attack written in Python.
“The affine cipher is a type of monoalphabetic substitution cipher, wherein each letter in an alphabet is mapped to its numeric equivalent, encrypted using a simple mathematical function, and converted back to a letter. The formula used means that each letter encrypts to one other letter, and back again, meaning the cipher is essentially a standard substitution cipher with a rule governing which letter goes to which. As such, it has the weaknesses of all substitution ciphers. Each letter is enciphered with the function (ax+b)\mod(26), where b is the magnitude of the shift.” – taken from Wikipedia – for further information see here.
In this repository you can find my version of the cipher and a simple script in written in Python that forces the cipher in a few seconds doing a Brute Force Attack.
git clone https://github.com/danfloyd111/affine-cipher && cd affine-cipher
gcc -o affine-cipher affine-cipher.c
python affine-cipher-brute-force.py (path)