encrypt.js

const crypto = require('crypto');

// Encrypt a message with a secret key
const message = 'This is a secret message';
const secretKey = 'This is a secret key';

// Create a 256-bit cipher key and initialization vector
const cipherKey = crypto.createHash('sha256').update(secretKey).digest();
const iv = crypto.randomBytes(16);

// Encrypt the message
const cipher = crypto.createCipheriv('aes-256-cbc', cipherKey, iv);
let encryptedMessage = cipher.update(message, 'utf8', 'hex');
encryptedMessage += cipher.final('hex');

console.log('Encrypted message:', iv.toString('hex') + encryptedMessage);

// Decrypt the message
const encryptedBuffer = Buffer.from(iv.toString('hex') + encryptedMessage, 'hex');
const decipher = crypto.createDecipheriv('aes-256-cbc', cipherKey, encryptedBuffer.slice(0, 16));

let decryptedMessage = decipher.update(encryptedBuffer.slice(16), 'hex', 'utf8');
decryptedMessage += decipher.final('utf8');

console.log('Decrypted message:', decryptedMessage);