Hey there!

Here's a quick lite-c conversion of the AES-128 implementation found at: https://github.com/kokke/tiny-AES128-C (more info on AES)

Note that this AES implementation is probably not secure against a variety of attacks. On top of that the author provides NO warranty.
I'm using it to encrypt game files.

Important note from aes.c:
Download: AES128_lite-c_19-06-2017.zip (Dropbox)
Download: AES128_lite-c_19-06-2017.zip (update 1) (Dropbox)

Edit: small update: Added (CBC mode) functions to encrypt or decrypt from and into the same buffer, rather than having to use both an input and an output buffer.

Just a note, using strong encryption for gamefiles is useless and simply just wasting time.
All files can easily be dumped live from memory.
You should use a simple XOR cypher with incrementing the steps.
Anyways thanks for the contribution.

Yes, I know about a few ways to do this, thanks for the info though. It's important to keep this in mind.
But I'm still sticking to my current approach since a simple xor encryption seems a bit too easy to break.
(in terms of being able to manipulate save files, textures, levels or other game data in a predictable manner)