Vigenere Cipher

Overview

This program is an implementation of the Vigenere Cipher.

https://en.wikipedia.org/wiki/Vigen%C3%A8re_cipher

The following steps are performed during encryption:

• Read the encryption key.
• Read the plain text input string.
• Remove all non-alpha characters from the key and plain text input.
• Convert any lower case characters to upper case in key and plain text.
• Apply the cipher.
• Display the encrypted text.

Build

Use the following command to build the program:

./build.sh

Usage

To encrypt a string:

./vigenere -k "KEY" -e "STRING TO ENCRYPT"

The above command returns:

CXPSREDSCXGPITR

To decrypt a string:

./vigenere -k "KEY" -d "CXPSREDSCXGPITR"

The above command returns:

STRINGTOENCRYPT