On Feb 3,  1:29pm, Manuel Bouyer wrote:
> > [...]
> > 	/etc/hosts		none
>
> I would set this one schg. On a secure system, /etc/hosts is used before
> dns, and critical machines are in /etc/hosts.
> Adding or changing entries in /etc/hosts can compromise the system.
> nsswitch.conf should also be schg (not listed here).

You're right, I agree.

> > [...]
> I played with system flags when I set up our firewall. Alone they're useless:
> why make /dev immutable if a root user can create devices elsewhere ?
> (well, they are not useless, but can be worked around).

The intention to make /dev immutable is not to disable creation of devices
elsewhere, but to protect your devices from being rm'ed by a malicious hacker.
One could disable device creation by checking securitylevel in mknod(2), but
that does not seem to make much sense to me (the devices aready present in /dev
can always be used). Once you're running at security level 2, disks, /dev/mem,
/dev/kmem (well, also /hackerdev/mem in that respect) are read-only, so what is
your concern?

-- Lex

-- 
Dr. Alexandre Wennmacher
Institut fuer Geophysik und Meteorologie         wennmach@geo.Uni-Koeln.DE
Universitaet zu Koeln                            phone  +49 221 470 - 3387
D-50923 Koeln                                    fax    +49 221 470 - 5198