[PLUG] firewall

[Michael Rasmussen]

Bruce Kilpatrick wrote:
> The Ubuntu faq states:
>
>         Does Ubuntu come with a firewall installed?
>
> Since Ubuntu doesn't run any daemons that listen to the outside world by
> default ...

That's factually correct.  It's also wrong.

A properly configured firewall not only controlls what comes in, but what goes
out.   Consider the trojaned windows system functioning as a spambot.  If it had a
firewall restricting SMTP connections to configured mail relays it couldn't spam.

> The rationale is that if a user's got a need for installing a
> world-facing daemon, they'll be aware that they should configure a
> firewall/ACL for it too.

This assumes the user realizes the risks and __remembers__ to do the firewall/acl
thing.

> Does this mean that I don't really need the firewall in the Actiontec
> DSL modem turned on?  What daemons that listen to the outside world
> might I have turned on in my experimentation with Ubuntu 5.10?

Leave it on.  An added layer of protection is a good thing.

What daemons might you have turned on?  web, database, mail ... who knows?  But
you can find out.

run:  `netstat -nt` and look for the word LISTEN.  If it's there you're running
something.


I think the Ubuntu stance on this issue is terrible.  netfilter is built into the
kernel.  iptables is available to use and there are many tools available to help
build rule sets.


-- 
   Michael Rasmussen, Portland, Ore, USA
  Be Appropriate && Follow Your Curiosity
        http://www.patch.com/words/