On Tue, 31 Dec 2013, Patrick O'Callaghan wrote:
On Mon, Dec 30, 2013 at 11:25 PM, Bill Oliver <vendor(a)billoblog.com> wrote:
In linux, is it possible to dictate two different actions upon login with different
passwords?
Short answer: no.
Longer answer: in computing almost anything is possible if you really want to achieve it.
Given that on Unix-style systems, including Linux, the login program can be changed, you
can modify the source
to do what you want. Of course you'll need to have superuser privileges to install it
in place of the system standard. Note that doing this may well open a can of worms, e.g.
you might have to modify
the format of the password file (and hence the library routines that access it), possibly
fiddle with SElinux settings, etc. etc.
If the conditions are relaxed slightly you can get a partial solution using the standard
login: write a Shell startup script (.profile or whatever) that allows the user to
discriminate between the two
modes, e.g. by using a timeout, detecting the initial state of the Shift (or Control or
whatever) key etc., in a way that is hopefully non-obvious to an observer. Probably not
reliable enough for
serious use.
Conclusion: better look for some other way to cover your tracks, and note that a forensic
investigation can be carried out without having you log in at all.
poc
Yeah, that's what I thought. I'm a little surprised that there hasn't been a
variant of linux developed for areas with intrusive government surveillance. I recently
noticed that the government of Venezuela has a government-developed distro (Canaima);
think there's some back doors in that? One would think that there would be a movement
to provide anti-governmental variants.
I know there's no perfect security. Back in the day, I had an acquaintance whose job
was to break into houses and install keyloggers on machines in people's homes. Of
course that was back when we still believed in silly things like search warrants.
Sigh. I guess I'll just have to continue keeping my plans for world domination on my
brother-in-law's computer... (Just kidding, NSA).
billo