Re: user not authorized to run X, strange variant

["David Zoll" <dzoll@nyscul.org>]

Erik Steffl wrote:
> 
> sena wrote:
> >
> > On 12/12/2000 at 11:35 -0800, Erik Steffl wrote:
> > >   my point was that these options do not help in what I think is by far
> > > most common situation. then again, I have no lies neither statistics to
> > > support this:-)
> > >
> > >   I mean the most common situations should be solved first, then special
> > > cases. maybe I'm missing something but I can't find any docs on this...
> > >
> > I think the most _appropriate_ approach is to make things secure above all.
> > That must be why X comes rootonly by default until someone changes it. Nice.
> 
>   that's the problem. the default is secure but the most typical (my
> assessment) setup cannot be made secure as you have to let anybody run
> X. what's the use of security measure that has to be disabled in most
> cases?

The most typical (by my assessment) setup is where X is run via *dm. 
The "allowed_users=rootonly" option works fine for that (I've only
tested it under gdm, but xdm and kdm should work the same).  This is the
default.

The most typical power-user's setup is where X is run via startx.  The
"allowed_users=console" option works fine for that.  These are power
users, so changing the default should be no problem for them.

I can't think of ANY setups where "allowed_users=console" gives
insufficient access to the X server; just in case, there's an
"allowed_users=anyone" option.  I, for one, don't want anybody running X
unless they're sitting in front of the box.


Earlier in the thread, Erik Steffl also wrote:
> I mean what's the point of having these options when basically only
> 'anybody' is usable? I mean you dont' want to run X as root, that does
> not make sense and if you run X most of the time (fairly common,
> probably most common situation for machines whe X is installed) then it
> makes sense to use xdm (or other *dm).

X, by which I mean the program /usr/bin/X11/X is ALWAYS run as root.  In
fact it is setuid root to make sure of this.  This is because it needs
access to privileged hardware (and possible privileged ports too, I
don't remember for sure).

If you run gdm, X is even run BY root, since gdm is running as root.  I
assume the other *dm's are the same in this respect.  This is why
"allowed_users=rootonly" works in this case.

Best of Luck,
-Gleef