NodeJS: aes-encrypt / aes-decrypt by using string password. (Browser compatible and I think as a secure way at this point ...)

aes-encrypt-decrypt.js

const aesjs = require('aes-js');
const pbkdf2 = require('pbkdf2');

const password = "mySecretPassword";
const message = "HelloWorld!";

const encrypted = encrypt(message, password);
console.log("encrypted:", encrypted); // 3ed20b7c474c96af513d1c
const decrypted = decrypt(encrypted, password);
console.log("decrypted:", decrypted); // HelloWorld!

function encrypt(msg, password, counter = 1) {
  // Encrypt
  const key = passwordToKey(password);
  // Convert text to bytes
  const textBytes = aesjs.utils.utf8.toBytes(msg);
  // The counter is optional, and if omitted will begin at 1
  const aesCtr = new aesjs.ModeOfOperation.ctr(key, new aesjs.Counter(counter));
  const encryptedBytes = aesCtr.encrypt(textBytes);
  // To print or store the binary data, you may convert it to hex
  const encryptedHex = aesjs.utils.hex.fromBytes(encryptedBytes);
  return encryptedHex;
}

function decrypt(encryptedHex, password, counter = 1) {
  // Decrypt
  // When ready to decrypt the hex string, convert it back to bytes
  const encryptedBytes = aesjs.utils.hex.toBytes(encryptedHex);
  const key = passwordToKey(password);
  // The counter mode of operation maintains internal state, so to
  // decrypt a new instance must be instantiated.
  const aesCtr = new aesjs.ModeOfOperation.ctr(key, new aesjs.Counter(counter));
  const decryptedBytes = aesCtr.decrypt(encryptedBytes);
  // Convert our bytes back into text
  const decryptedText = aesjs.utils.utf8.fromBytes(decryptedBytes);
  return decryptedText;
}

function passwordToKey(password, salt, keyBits = 192) {
  if (!salt) {
    salt = password;
  }
  const key = pbkdf2.pbkdf2Sync(password, salt, 1, keyBits / 8, 'sha512'); // AES192
  return key;
}