Yubilock is a simple program that will lock your screen if a Yubikey is removed from the computer.

As others have pointed out, it can be achieved more elegantly with a udev rule, I'll keep this here for posterity and to serve as a reference for dbus/python3 stuff in case somebody needs it.

The udev rule in question is:

ACTION=="remove", ATTRS{idVendor}=="1050", RUN+="/bin/loginctl lock-sessions"

Adding this to a /etc/udev/rules.d/80-yubilock.rules file should do the trick.

That will lock the screen for any USB device made by Yubico, you could add your specifi device ID as ATTRS{idProduct} if you want to narrow that down further.

Thanks to masta from reddit!

First of all: why not? :)

I find myself working from cybercafes/coworking spaces quite often, and realized whenever I had to leave my computer, I systematically did two things:

1. Remove my Yubikey from the USB port it's plugged into
2. Lock my screen

This program is a simple attempt at optimising this aspect of my life. Removing the Yubikey now triggers a screen lock!

Simple!

Yubilock is currently thought to be run on Ubuntu, using python3. As such, the following (system) dependencies are required:

sudo apt-get install python3 python3-pyudev python3-dbus

This program depends on DBus's system and session busses to be available to the running user. Therefore, it needs a working DBus environment. Normal logged in users on a default Ubuntu install should have this, but i.e. containers won't by default.

Simply run the ./yubilock script as a normal logged in user from a terminal.

It doesn't do anything fancy yet, and will simply log information about Yubikeys on stdout.

An applet? Who knows!