Thesis project 2020-2021
Topic: Bare-metal application for x86 processors on a QEMU/KVM hypervisor
Requirements:
The application has to encrypt/decrypt data with asymmetric encryption sent over virtio-serial and to return results over the same connection.
The application has to implement the virtio-serial connection.
A bare-metal application running on the QEMU hypervisor implementing the RSA algorithm for asymmetric encryption and a serial driver for the serial connection. The virtio-serial driver was abandoned after a month of fruitless debugging.
The documentation can be found as a pdf in the latest release. It's written in Bulgarian because that's one of the requirements and I am too lazy to translate it. Here's "documentation lite", I guess:
docs/ - The .latex and .tex files for the documentation
kernel/ - The barebones assembly and C code for running anything on bare metal
serial/ - A regular serial driver for communication
virtio/ - A (currently broken) virtio-serial driver for communication
encryption/ - An implementation of RSA
builds/ - Makefiles and glue code for different combinations of the 4 folders mentioned above
tiny-bignum-c/ - A modified fork of kokke/tiny-bignum-c because I didn't know .patch files existed
The code needs to be compiled with a gcc cross-compiler. Figure 4.7 of the documentation lists the commands needed to make such a compiler, but I got them from the OSDev wiki so you can just follow that. I have also experimented with using the zig compiler as an off-the-shelf substitution but I couldn't get it to link together.
My biggest technical mistake was to choose xorshift as my pseudo-rng, compromising the security of the application while actually taking more effort to implement than just using RDRAND. My documentation also wasn't perfect, despite my best efforts. Despite that I got my A. 😄