Encrypt and decrypt buffers in nodejs

crypto-buffer.js

// Part of https://github.com/chris-rock/node-crypto-examples

var crypto = require('crypto'),
    algorithm = 'aes-256-ctr',
    password = 'd6F3Efeq';

function encrypt(buffer){
  var cipher = crypto.createCipher(algorithm,password)
  var crypted = Buffer.concat([cipher.update(buffer),cipher.final()]);
  return crypted;
}
 
function decrypt(buffer){
  var decipher = crypto.createDecipher(algorithm,password)
  var dec = Buffer.concat([decipher.update(buffer) , decipher.final()]);
  return dec;
}
 
var hw = encrypt(new Buffer("hello world", "utf8"))
// outputs hello world
console.log(decrypt(hw).toString('utf8'));

Yes, I download encrypted buffer with a rest api like content-type application/pdf and attachments headers. What I'm looking for is to protect the pdf with a password, so I can open it only with this password.

@hdiaz-nectia Have you got the solution for this case? I wanted to implement this same case