Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 28 Mar 2000 13:54:01 -0800
From:      Scott Hess <scott@avantgo.com>
To:        "Brian O'Shea" <boshea@ricochet.net>
Cc:        Kelly Yancey <kbyanc@posi.net>, freebsd-net@FreeBSD.ORG
Subject:   Re: Security of NAT "firewall" vs. packet filtering firewall.
Message-ID:  <20000328135401.A17746@river.avantgo.com>
In-Reply-To: <20000328130850.Z330@beastie.localdomain>
References:  <20000328113534.W330@beastie.localdomain> <Pine.BSF.4.05.10003281436440.3162-100000@kronos.networkrichmond.com> <20000328130850.Z330@beastie.localdomain>

next in thread | previous in thread | raw e-mail | index | archive | help
On Tue, Mar 28, 2000 at 01:08:50PM -0800, Brian O'Shea wrote:
> Thank you for your response.  This is what I thought, although I
> should have clarified my question.  I was wondering if there is any
> added security to having packet filtering rules on the router, in
> addition to NAT.  Since there are no services to exploit (ignoring
> sshd for the moment), what rules would I add?  If there are no
> services running, then there is no need to block any ports.  But are
> there other types of vulnerabilities that I should be worried about?

You could tell the packet filter to only allow packets to the
ssh port.  Sounds redundant, but it certainly does prevent you
from accidentally opening up a hole at some point.

You might want to log packets, on the off chance that someone is
doing something interesting.

You might want to adjust whether non-ssh packets are rejected, or
simply dropped on the floor.  Rejecting the packet gives an immediate
"Connection denied" response to probes, whereas dropping the packet
just leaves the probe high&dry.

Later,
scott


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-net" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20000328135401.A17746>