Crate with an example of a kernel module in Rust
This repo is a Makfile with a Rust project that, using Kbuild, the kernel's build system, will generate
a kernel module file named parrot.ko.
The kernel module creates a char device that on every read() call, will return a new frame of an
ASCII art party parrot in your terminal, which ultimately makes an animation appear when used with cat.
Well... the longer story is that I was talking with a colleague, rpless,
about parrot.live. This came up
during the same conversation as my desire to do something in kernel space. This also came up
in the same conversation as my love of Rust. He suggested jokingly I should do exactly what I did in this
project. So I did!
The shorter answer is "for science!"
A more serious answer is that I was interested in seeing how compatible Rust actually is on a C ABI level. I was also interested in digging into Rust internals a bit more. Debugging some of the initial issues that came up trying to load the Rust kernel module was pretty fun and taught me a lot about the compiler.
# Make sure Rust in installed via rustup
curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh
# Build and load the kernel module
make
sudo insmod parrot.ko
# Find the char device ID in the kernel
cat /proc/devices | grep parrot
# Make the device node exposing the char device
sudo mknod /dev/parrot c [ID_FROM_PREVIOUS_COMMAND] 0
# Party hard!
cat /dev/parrot
The frames for the parrot were shamelessly lifted from parrot.live.
Please go there if you like the ASCII art and shower the maker with praise - they're not mine.
I'm a lot of things but ASCII artist is not one of them.