From owner-freebsd-questions  Sat Sep 27 20:28:27 1997
Return-Path: <owner-freebsd-questions>
Received: (from root@localhost)
          by hub.freebsd.org (8.8.7/8.8.7) id UAA02983
          for questions-outgoing; Sat, 27 Sep 1997 20:28:27 -0700 (PDT)
Received: from awfulhak.demon.co.uk (awfulhak.demon.co.uk [158.152.17.1])
          by hub.freebsd.org (8.8.7/8.8.7) with ESMTP id UAA02939
          for <freebsd-questions@FreeBSD.ORG>; Sat, 27 Sep 1997 20:28:15 -0700 (PDT)
Received: from gate.lan.awfulhak.org (localhost [127.0.0.1])
	by awfulhak.demon.co.uk (8.8.5/8.8.5) with ESMTP id EAA09001;
	Sun, 28 Sep 1997 04:16:26 +0100 (BST)
Message-Id: <199709280316.EAA09001@awfulhak.demon.co.uk>
X-Mailer: exmh version 2.0zeta 7/24/97
To: Eivind Eklund <perhaps@yes.no>
cc: Brian Somers <brian@awfulhak.org>, bruce@zuhause.mn.org,
        freebsd-questions@FreeBSD.ORG
Subject: Re: sendmail and ppp -auto 
In-reply-to: Your message of "Sun, 28 Sep 1997 01:33:57 +0200."
             <199709272333.BAA13407@bitbox.follo.net> 
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Date: Sun, 28 Sep 1997 04:16:26 +0100
From: Brian Somers <brian@awfulhak.org>
Sender: owner-freebsd-questions@FreeBSD.ORG
X-Loop: FreeBSD.org
Precedence: bulk

> > 
> > > I just started using ppp -auto, and whenever sendmail starts up or I
> > > get any new mail, ppp connects to my ISP.  How do I trace this?  I
> > > don't know how.  Is there something I should add to my sendmail
> > > configuration? For that matter, how do I attach bpf0 to tun0, and where
> > > is documentation on setting up ipfilters to reject the packet sendmail
> > > is sending?  Would it help to set up a caching named?
> > 
> > There's a bit in the FAQ now (in the networking section - 10.7.9 
> > currently).
> > 
> > Essentially, you need to "set log +tcp/ip", determine the rogue 
> > program (sendmail in your case) and add a few lines to ppp.conf:
> > 
> >   set dfilter 1 deny udp src eq 25
> >   set dfilter 2 deny udp dst eq 25
> >   set dfilter 3 permit 0/0 0/0
> 
> Eh - this looks completely bogus to me.
> 
>    set dfilter 1 deny udp src eq 53
>    set dfilter 2 deny udp dst eq 53
>    set dfilter 3 permit 0/0 0/0
> 
> would be it, wouldn't it?  But - this denies all DNS requests the
> ability do dial out.  Not Good.  It is much better to fix sendmail
> (and Win95).

You're right of course - the rogue program is the resolver as used by 
sendmail, and if the person wants sendmail to auto-send stuff when it 
*really* has something to do, sendmail needs fixing (as you posted in 
answer to another question).

Of course you *could* add that Q. & A. to the FAQ in as a "why does 
ppp make a connection at boot time"..... *nudge*

> Eivind.

Cheers.

-- 
Brian <brian@Awfulhak.org>, <brian@FreeBSD.org>, <bri@OpenBSD.org>
      <http://www.Awfulhak.org>
Don't _EVER_ lose your sense of humour....