From owner-freebsd-security Wed Nov 29 7:21:25 2000 Delivered-To: freebsd-security@freebsd.org Received: from point.osg.gov.bc.ca (point.osg.gov.bc.ca [142.32.102.44]) by hub.freebsd.org (Postfix) with ESMTP id 8596937B400 for ; Wed, 29 Nov 2000 07:21:22 -0800 (PST) Received: (from daemon@localhost) by point.osg.gov.bc.ca (8.8.7/8.8.8) id HAA18027; Wed, 29 Nov 2000 07:20:26 -0800 Received: from passer.osg.gov.bc.ca(142.32.110.29) via SMTP by point.osg.gov.bc.ca, id smtpda18025; Wed Nov 29 07:20:26 2000 Received: (from uucp@localhost) by passer.osg.gov.bc.ca (8.11.1/8.9.1) id eATFKKx13553; Wed, 29 Nov 2000 07:20:20 -0800 (PST) Received: from cwsys9.cwsent.com(10.2.2.1), claiming to be "cwsys.cwsent.com" via SMTP by passer9.cwsent.com, id smtpdF13543; Wed Nov 29 07:19:28 2000 Received: (from uucp@localhost) by cwsys.cwsent.com (8.11.1/8.9.1) id eATFJSN20826; Wed, 29 Nov 2000 07:19:28 -0800 (PST) Message-Id: <200011291519.eATFJSN20826@cwsys.cwsent.com> Received: from localhost.cwsent.com(127.0.0.1), claiming to be "cwsys" via SMTP by localhost.cwsent.com, id smtpdl20822; Wed Nov 29 07:19:25 2000 X-Mailer: exmh version 2.2 06/23/2000 with nmh-1.0.4 Reply-To: Cy Schubert - ITSD Open Systems Group From: Cy Schubert - ITSD Open Systems Group X-OS: FreeBSD 4.2-RELEASE X-Sender: cy To: Dominick LaTrappe Cc: freebsd-security@FreeBSD.ORG Subject: Re: filtering ipsec traffic In-reply-to: Your message of "Tue, 28 Nov 2000 23:49:09 EST." Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Wed, 29 Nov 2000 07:19:25 -0800 Sender: owner-freebsd-security@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org In message , Dominick LaTrappe writes: > It seems that, on the way in, ipfilter on FreeBSD gets packets before KAME > does, and on the way out, after. This limits ipfilter to inspecting > traffic from IPsec peers on on layer 3 only. Since I see no > packet-filtering mechanism in KAME itself, this presents a severe > limitation, namely that I must trust my IPsec peers enough for their > traffic to bypass any layer-4 filters. > > Is there some way to give ipfilter two passes, pre-KAME and post-KAME? > The even better fix, I suppose, would be to have 4 ipfilter rulesets > instead of 2 -- pre-KAME in, pre-KAME out, post-KAME in, post-KAME out. > > In the mean time, I'm using tcpwrappers as a last-line-of-defense where I > can, but it's not enough. Looking at the source, I don't see any references to IPFW either, meaning this is not a simple copy-the-code change. One option would be to set up a point-to-point IPSec tunnel between the two gateways, then use an IP tunnel within it. Alternatively you could pipsecd which sets up an IPSec tunnel and defines a tun interface, which can be filtered using IP Filter or IPFW. Regards, Phone: (250)387-8437 Cy Schubert Fax: (250)387-5766 Team Leader, Sun/DEC Team Internet: Cy.Schubert@osg.gov.bc.ca Open Systems Group, ITSD, ISTA Province of BC To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-security" in the body of the message