RickRolling The Trolls

This post is inspired by a video a friend (Reashlin) sent to me (embedded below). In their company it is policy to lock computers when users are away from them, and if a machine is left unlocked it is customary to tell the supervisor in a “friendly” email from the account of the person in who left their machine unlocked.

Knowing this, Reashlin’s colleague wrote a C# application that leaves the computer running whatever it was before until the mouse is moved, when it switches to a full screen RickRoll video with the machine locked.

A whole C# application to do this seemed a bit much, so I distilled the whole thing into the following 4 line bash script. The script is quite simple. It simply waits for input from /dev/input/mice then spawns full screen mplayer in the background, and xtrlock in the foreground. xtrlock is a handy little program that captures all keyboard/mice events until the users password is entered, a bit like a transparent xlock. There is an issue with this script if the user is proficient in keyboard short-cuts they might never touch the mouse… but that’s something for another day.

If the others at canthack.org try and do this to me again they will be getting a surprise (well not that much; they do read this after all).

#!/bin/bash
sudo cat /dev/input/mice | read -n 1
mplayer -fs rick.flv &
xtrlock

About Mex

Computer science PHD student from Canterbury. Interested in concurrency, mostly CSP and Occam-pi.
This entry was posted in Programming, Unix. Bookmark the permalink.

2 Responses to RickRolling The Trolls

  1. Johannes says:

    Great post, great blog, great hacks!
    I tested this neat little 4Liner and it worked just perfect! The key part for me was at Line 2, the others are straight forward. But on my system(OpenSuse11.4) there is no xtrlock and I haven’t figured out the equal command so far. Any suggestions?

    By the way; to catch keyboard affine users simply replace
    /dev/input/mice
    by
    /dev/input/event0

    Right?

    Anyway, thanks for sharing and cheers from Austria!

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