Simple message encryption/decryption with AES

aes-encrypt-decrypt-message.scala

  val iv = new IvParameterSpec(Base64.getDecoder.decode("V4kfws5dKNgK0ORjb8jCtQ=="))

  def mkKeySpec(key: String, load: Int) = {
    val digest = MessageDigest.getInstance("SHA-256")
    var bytes = key.getBytes(UTF_8)
    for (_ <- 0 until load) {
      bytes = digest.digest(bytes)
    }
    new SecretKeySpec(bytes, "AES")
  }

  def encrypt(msg: String, key: String, load: Int): String = {

    val cipher = Cipher.getInstance("AES/CTR/NoPadding")
    cipher.init(Cipher.ENCRYPT_MODE, mkKeySpec(key, load), iv)

    val msgBytes = msg.getBytes(UTF_8)
    val encBytes = cipher.doFinal(msgBytes)
    Base64.getEncoder.encodeToString(encBytes)
  }

  def decrypt(msg: String, key: String, load: Int): String = {

    val cipher = Cipher.getInstance("AES/CTR/NoPadding")
    cipher.init(Cipher.DECRYPT_MODE, mkKeySpec(key, load), iv)

    val msgBytes = Base64.getDecoder.decode(msg)
    val decBytes = cipher.doFinal(msgBytes)
    new String(decBytes, UTF_8)
  }

iv must be recreated for each message with the same key