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From: Archie Cobbs <archie@whistle.com>
Message-Id: <199702051901.LAA23740@bubba.whistle.com>
Subject: Re: Single socket version of natd
In-Reply-To: <199702050149.BAA29882@awfulhak.demon.co.uk> from Brian Somers at "Feb 5, 97 01:49:00 am"
To: brian@awfulhak.demon.co.uk (Brian Somers)
Date: Wed, 5 Feb 1997 11:01:57 -0800 (PST)
Cc: brian@utell.co.uk, cmott@srv.net, julian@whistle.com, eivind@dimaga.com,
        ari.suutari@ps.carel.fi, hackers@freebsd.org
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> Does anyone know of a reason (besides the divert(4) man page) that the
> sum on incoming packets is zero'd ?
> The code says:
> 
> [.....]
>         if (hlen == sizeof(struct ip)) {
>                 ip->ip_sum = in_cksum_hdr(ip);
>         } else {
>                 ip->ip_sum = in_cksum(m, hlen);
>         }
>         if (ip->ip_sum) {
>                 ipstat.ips_badsum++;
>                 goto bad;
>         }
> [.....]
> 
> Is there any problems with changing this to
> 
>         u_short sum;
> .....
>         if (hlen == sizeof(struct ip)) {
>                 sum = in_cksum_hdr(ip);
>         } else {
>                 sum = in_cksum(m, hlen);
>         }
>         if (sum) {
>                 ipstat.ips_badsum++;
>                 goto bad;
>         }
> 
> (and updating divert(4)) ?

Please do!

-Archie

___________________________________________________________________________
Archie Cobbs   *   Whistle Communications, Inc.  *   http://www.whistle.com