Simple implementations of the Caesar and Vigenere ciphers, as well as a command-line interface to call them with.
First run make to compile, then can run via the command-line to call cli(), such as crypto.c caesar-encrypt 5 HELLO.
Always call like crypto.c [method] [key] [message]. Has the methods of caesar-encrypt, caesar-decrypt, vigenere-encrypt and vigenere-decrypt.