[CentOS] Block network at logoff on workstation

On Wed, Feb 3, 2010 at 9:36 PM, David McGuffey
<davidmcguffey at verizon.net> wrote:
> I'm trying to reduce the attack surface to a home machine that is always
> on and connected to the Internet.  It is running CentOS 5.4, with tight
> iptables rules and sits behind a Verizon FiOS firewall/switch also
> configured with tight rules.
>
> I was wondering how to best block all network access to it when I log
> off...then unblock it when I log on. Changing iptables requires root
> access...as does running ifdown and ifup scripts.
>
> I could change the permissions on ifdown and ifup and run them from the
> login/logout scripts, but I'd prefer not to do that.

Many window managers can run scripts on login and logout. You could
create a script uses sudo to enable/disable the interface then run it
on login/logout.