Ask Slashdot: Ubuntu Lockdown Options?

First time accepted submitter clava writes "We have a desktop Java testing application that is going to be administering tests to students on lab computers running Ubuntu 10.x. These computers are used by the students for other purposes and we're not allowed to create special users or change the OS configuration. When the testing app is launched, we need to restrict users from exiting the app so they can't do things like search the internet for answers or use other applications. Is there a good way to put an Ubuntu machine in kiosk mode or something via our application and have exiting kiosk mode be password protected? Any ideas are appreciated."

Comments

Depends how locked-down

[Anonymous Coward]

I'm afraid if you want it actually locked-down, you're pretty screwed. You can't really disable things like switching to a tty with ctrl-alt-f1 without "changing the OS configuration."

Re:Depends how locked-down

[c 0xFF]

Disabling TTY switching is a pretty simple change, though, and won't affect the general use of the system.

In fact, you might as well use this to your advantage: start up a new X server instance, but don't start up the window manager. Run your java app in this server.

Now all a student can do is take the test -- there's no way to do anything besides take the test unless they can switch using ctrl-alt-F*, which has been disabled.

That's as near to a "kiosk mode" as I can figure.

Boot from USB or CD-ROM?

[hawguy]

Create your own custom locked down kiosk boot image and require users to boot from that? Keep in mind that users might take the boot media home with them so they'll have a copy of the test app if you store it locally (as opposed to retrieving it from a website)

Here's an example:

http://jacob.steelsmith.org/content/ubuntu-kiosk-based-910

(I'm not vouching for this particular implementation, I just found it through a quick google search).

Re:Boot from USB or CD-ROM?

[phoenix_rizzen]

That's what we do. All our Linux stations boot off the network and use NFS mounts for everything. For government exams, teachers reboot the stations into "Exam Mode" which disables everything possible, launches a bare-bones X11 session with Firefox as the "WM", with all settings locked in, including an add-on that let's you specify a list of sites that are accessible, blocking access to everything else.

Took a few iterations to get the configuration locked down completely, but there's really no better way to find the holes than watch a class of students try to break it. :)

It's not bullet-proof, but we've made it hard enough that it's very obvious when a student is trying to break out of the box that anyone watching the lab will notice. :)

If you can't change the OS config, you can't lock it down.

LiveCD?

[grahamsaa]

Not sure how hard this would be to do, but it seems like it would be fairly easy to boot from a livecd/usb key. If you remove packages you don't want the end user to have access to (it's hard to browse the web for test answers if there's no browser installed) that should address at least some of your concerns. An added bonus is that if you need to repurpose the machine, or if it doesn't need to be in test mode all the time, a simple reboot could restore it to a vanilla version of the OS.

Google???

[muphin]

did you even google your question?
http://lmgtfy.com/?q=ubuntu+lockdown

maybe this will help you
http://ubuntuforums.org/showthread.php?t=456549
http://users.telenet.be/mydotcom/howto/linuxkiosk/ubuntu01.htm
http://library.gnome.org/admin/system-admin-guide/stable/menustructure-13.html.en