File Encryption/Decryption with AES using Linux

Question

I'm using the OpenWrt Linux distribution and I want to encrypt a file using AES.

How can I do that quickly and easily, and how can I—or someone else—decrypt it again?

Answer 1

The quickest and easiest way is to use openssl util (provided by openssl-util package). For example, to encrypt a file, issue the following command:

openssl enc -aes-256-cbc -in file.txt -out file.enc

To decrypt:

openssl enc -d -aes-256-cbc -in file.enc -out file.dec

Answer 2

The openssl encryption is not a good solution according to this, so please don't use it.

I've used https://www.aescrypt.com/ in the past and I was happy with it. If you want something that has been around for a while - that's not a bad start. It also has both a UI and a cli.

The fact that there is no small, easy to use and super simple cli tool for this purpose annoyed me so much that I sat down and wrote this https://github.com/ro-tex/aes256cli. I literally wrote it while this discussion was open on my screen, so I'm making no claims as to how good of a solution it is. I just wanted something that will do what I need with zero friction and this is good enough for me.

Answer 3

To encode:

cat 'yourfile' | openssl aes-128-cbc > 'encrypted file'

To decode: First, you have to remember your password which you used to encode, then:

cat 'encrypted file' | openssl enc -d -aes-128-cbc -k 'Your password' > 'decrypted file'