From: joel@rac3.wam.umd.edu (Joel M. Hoffman) Subject: Password protection when changing VC's ?? Date: Fri, 14 May 1993 13:47:51 GMT
Here's the story: I'd like to let other users use the Linux console
to login, but I don't (obviously) want to give them root access, or
access to my account. However, I also don't want to logout whenever
they use the console; I also generally have top running as root on VC
8, and don't want to have to kill/restart that every time.
So what I'd like is some sort of password protection on changing VC's.
The idea would be that to change to a new VC, one must know the
password. That way, I could switch to VC 1, say, and let anyone and
everyone use it to login/logout, and when I get back to the computer
have full access to all of my stuff, as joel and as root, running on
the other VC's.
But how to implement this? The easiest way would be in ther kernel,
but I don't want to do that. Seems like too much of a kludge even for
me. But I understand processes can now take action when a VC switch
is requested. Is this true? Can the process also deny the VC switch?
If so, I think a very nice feature to add to getty would be optional
password protection when switching out of the current VC. That way,
I'd run ordinary getty on VC's 2-8, and password_getty on VC 1. In
order to switch out of VC 1, users would have to enter the password.
I suppose the shell would have to cooperate, too.
I realize that this is not going to be perfectly safe. Users can
always ``exec ordinary_sh'' or whatever, but the idea here is not to
protect against hackers trying to break into the system (they probably
have their own boot disk anyway), but against new users, who have
never used Unix and are exploring. I don't want them playing around
and finding my root shell when they try to find out what fdisk
does....
Comments?
-Joel
(joel@wam.umd.edu)
--
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|_|~~ Germany, Europe. 1943. "The diameter of the bomb was 30 centimeters,
__|~| 16 Million DEAD. and the diameter of its destruction, about 7
meters, and in it four killed and 11 wounded.
cnc Bosnia, Europe. 1993. And around these, in a larger circle of pain
cnc HOW MANY MORE? and time, are scattered two hospitals and one
cemetery. But the young woman who was buried in
the place from where she came, at a distance of more than
than 100 kilometers, enlarges the circle considerably. And the
lonely man who is mourning her death in a distant country incorporates
into the circle the whole world. And I won't speak of the cry of the orphans
that reaches God's chair and from there makes the circle endless and godless."
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