Different actions on different passwords?

Patrick O'Callaghan pocallaghan at gmail.com
Tue Dec 31 00:43:49 UTC 2013


On Mon, Dec 30, 2013 at 11:25 PM, Bill Oliver <vendor at 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
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.fedoraproject.org/pipermail/users/attachments/20131231/fbe9f12e/attachment.html>


More information about the users mailing list