From owner-freebsd-current  Sat Aug 24 15:22:54 1996
Return-Path: owner-current
Received: (from root@localhost)
          by freefall.freebsd.org (8.7.5/8.7.3) id PAA04243
          for current-outgoing; Sat, 24 Aug 1996 15:22:54 -0700 (PDT)
Received: from post.io.org (post.io.org [198.133.36.6])
          by freefall.freebsd.org (8.7.5/8.7.3) with ESMTP id PAA04237
          for <current@freebsd.org>; Sat, 24 Aug 1996 15:22:50 -0700 (PDT)
Received: from zot.io.org (taob@zot.io.org [198.133.36.82]) by post.io.org (8.7.5/8.7.3) with SMTP id SAA19578; Sat, 24 Aug 1996 18:22:36 -0400 (EDT)
Date: Sat, 24 Aug 1996 18:22:36 -0400 (EDT)
From: Brian Tao <taob@io.org>
To: Bill Paul <wpaul@skynet.ctr.columbia.edu>
cc: current@freebsd.org
Subject: Re: rarpd broken on 2.2-960801-SNAP?
In-Reply-To: <199608242010.QAA04360@skynet.ctr.columbia.edu>
Message-ID: <Pine.NEB.3.92.960824181350.28538Q-100000@zot.io.org>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
Sender: owner-current@freebsd.org
X-Loop: FreeBSD.org
Precedence: bulk

On Sat, 24 Aug 1996, Bill Paul wrote:
>
> This confused me greatly because NetBSD did (does?) use htons(). I
> could swear I read somewhere that this was due to a bug in BPF. It's
> possible someone fixed the bug, making the htons() necessary again.

    Yeah, something must be different between the bpf in -stable and
the one in -current.  htons() is necessary with -current for rarp
replies to work.  The comments in FreeBSD-current and NetBSD-current
can probably be taken out now:

NetBSD-current:
#ifdef __FreeBSD__
        /* BPF (incorrectly) wants this in host order. */
        ep->ether_type = ETHERTYPE_REVARP;
#else
        ep->ether_type = htons(ETHERTYPE_REVARP);
#endif


FreeBSD-current:
        /*
         * XXX   Using htons(ETHERTYPE_REVARP) doesn't work: you wind
         * up transmitting 0x3580 instead of the correct value of
         * 0x8035. What makes no sense is that the NetBSD people
         * do in fact use htons(ETHERTYPE_REVARP) in their rarpd.
         * (Thank god for tcpdump or I would never have figured this
         * out.)
         */
        ep->ether_type = htons(ETHERTYPE_REVARP);

> Incidentally, you might try using a newer version of rarpd. If you
> grab the new bpf distribution from ftp.ee.lbl.gov (bpf.tar.Z) you'll
> see it has an updated rarpd in it. You should be able to compile it on
> FreeBSD-current (I did it the other day, but didn't get the chance to
> really play with it). You may not need the ethernet.c module that they
> supply for reading /etc/ethers since FreeBSD now has ether_aton() and
> friends in libc.

    I've got the source here too, but I haven't tried using it yet,
since the htons()'d rarpd works here.  Now I have a similar problem
with the X terminals timing out waiting for a response from the
bootparamd server.  It works the first time (so they can NFS-mount
their filesystems), but fails the second (presumably after they've
ifconfig'd their interfaces).  Must be some broadcast or netmask
issue... *sigh*.
--
Brian Tao (BT300, taob@io.org, taob@ican.net)
Senior Systems and Network Administrator, Internet Canada Corp.
"Though this be madness, yet there is method in't"