node-aescrypt

A node implementation of the AES Crypt https://www.aescrypt.com/ file encryption format.

How to use this package

This package exposes two different interfaces. If you are just interested in encrypting secrets on your own workstation, you can use the CLI version. If you want to use this in an node application, you can import the node library.

CLI

This simplest way to get started encrypting files is to use NPX to use the executable without necessarily "installing" it. To encrypt a local file you can simply execute:

$ npx node-aescrypt -e -p SUPER_SECURE_PASSWORD README.md

In this case, I'm encrypting the file README.md. After this command executes, you will see a new file in your current directory called README.me.aes. To decrypt this file you can use:

$ npx node-aescrypt -d -p SUPER_SECURE_PASSWORD README.md.aes

This will recreate the README.md file.

For a little more complicated of an example, you can pipe in data from the command line, so you could archive, compress, and then encrypt a directory like this:

$ tar -czf - -C src/ . | npx node-aescrypt -e -p SUPER_SECURE_PASSWORD -o my-src.tgz.aes

And then if you wanted to reconstitue that directory, you can move the my-src.tgz.aes file where ever you need it and execute:

$ npx node-aescrypt -d -p SUPER_SECURE_PASSWORD -o - my-src.tgz.aes | tar -pxzf -

Library

The primary reason I built this package was actually to integrate it into build systems. I planned to use the simple AES Crypt https://www.aescrypt.com/ app to encrypt secrets, and then this library, which is binarily compatibile with it, to decrypt on the fly using ENV variables to store my password.

To use the library version you should import the Decrypt or Encrypt classes from the module. These classes implement the node stream.Transform interface, so that they can be piped through by any Readable and/or Writable stream. So for example if you wanted to encrypt a file you could do this:

import { createReadStream, createWriteStream } from 'fs';
import { Encrypt } from 'node-aescrypt';

const from = createReadStream('somefile.txt');
const to = createWriteStream('somefile.txt.aes');
const through = new Encrypt('SUPER_SECURE_PASSWORD');

from
  .pipe(through)
  .pipe(to)
  .on('error', () => console.error('Oh no!  Something went wrong.'))
  .on('finish', () => console.log('All done.'));

For decrypting, it is the exact same process, but make sure the from stream is your encrypted file, the to stream is to a new file to put the decrypted data into, and you use the Decrypt class instead of the Encrypt class.

This makes the library very flexible because you can chain these streams in many different ways. For example, you could pipe the data through a Zlip https://nodejs.org/api/zlib.html transformer before you pipe it through the Encrypt object. You could even serve it from a server by piping it into an http.ServerResponse https://nodejs.org/api/http.html#http_class_http_serverresponse object.