Simple AES in JavaScript - Part I

Recently I needed to store an encrypted value in a database table for a Cloudflare Worker. A simple way to do this was with AES and a passphrase.

Install dependency

crypto-js is required:

npm install crypto-js

Encryption

const cryptoJS = require('crypto-js');

const encrypt = (stringValue) => {
  const passphrase = "sssh-its-a-secret";
  return cryptoJS.AES.encrypt(stringValue, passphrase).toString();
};

Decryption

const cryptoJS = require('crypto-js');

const decrypt = (ciphertext) => {
  const passphrase = "sssh-its-a-secret";
  const bytes = cryptoJS.AES.decrypt(ciphertext, passphrase);
  return bytes.toString(cryptoJS.enc.Utf8);
};

Example

const ciphertext = encrypt("don't be evil");
console.log(ciphertext);
// U2FsdGVkX1+WBqXF5xgowgP5ZubzrDBGYofLloWaafU=
const stringValue = decrypt(ciphertext);
console.log(stringValue)
// don't be evil

A non-dependency approach

Modern Node.js ships with a native Crypto module. A future post will show how to use that to achieve a similar result as above.

References

crypto-js