Text Ciphers

Monoalphabetic ciphers (substitution cipher) and Vigenère square ciphers (US ASCII alphabet only (A-Z)) for use with node.js or CommonJS.

Note in almost all cases using this package for actual cryptography is a pretty bad idea. These were created for fun and are intended for educational purposes only.

Install

npm i text-ciphers

Examples

Monoalphabetic cipher

const MonoAlphabeticCipher = require('text-ciphers').MonoAlphabeticCipher;
const monoalphabeticCipher = new MonoAlphabeticCipher({
	substitution: MonoAlphabeticCipher.createKeyByShift(-5)
});

// outputs 'oczlpdxfwmjriajsephkzyjqzmoczgvutyjb'
const enciphered = monoalphabeticCipher.encipher('The Quick Brown Fox Jumped Over the Lazy Dog');

//outputs 'thequickbrownfoxjumpedoverthelazydogs'
const deciphered = monoalphabeticCipher.decipher(enciphered);

Vigenère cipher

const VigenereCipher = require('text-ciphers').VigenereCipher;
const vigenereCipher = new VigenereCipher({
	keyword: 'hopper'
});

const enciphered = vigenereCipher.encipher('The Quick Brown Fox Jumped Over the Lazy Dog');

const deciphered = vigenereCipher.decipher(enciphered);

Options

preserveSpaces - Preserve spaces in the text (default = false) preserverOther - Preserve other characters (non A-Z and spaces) in the text (default = false);

MonoAlphabeticCipher options

substitution - Substitution alphabet to use (required)

VigenereCipher options

keyword - string to use to encipher and decipher (required) square - 26x26 square to use for enciphering and deciphering (optional, default = false) randomSquare - Use a randomized 26x26 character square (optional, default = false)

Utility methods

MonoAlphabeticCipher

MonoAlphabeticCipher.createKey(keyword) - create substitution alphabet from a key or phrase MonoAlphabeticCipher.createKeyByShift(shiftPlaces) - create substitution alphabet by shifting letters to the left or right shiftPlaces spaces MonoAlphabeticCipher.createKeyRandom() - create a substitution alphabet by randomizing the letters A-Z (Fischer-Yates shuffle)

VigenereCipher

VigenereCipher.createSquare(random) - create a 26x26 square for use with a Vigenère cipher. boolean random default = false

See tests in /test for examples for using various options and static methods

Tests

npm test