byte-swapping constant is good.  i've updated my tree.

> > @@ -764,3 +759,3 @@
> >  		 */
> > -		if (mff || ip->ip_off) {
> > +		if (mff || ntohs(ip->ip_off)) {
>Don't need to byte-swap if you're testing != 0.

	for completeness i'd like to have it.

> > Index: netinet/raw_ip.c
> > ===================================================================
> > RCS file: /cvsroot/syssrc/sys/netinet/raw_ip.c,v
> > retrieving revision 1.61
> > diff -u -1 -r1.61 raw_ip.c
> > --- netinet/raw_ip.c	2002/06/09 16:33:43	1.61
> > +++ netinet/raw_ip.c	2002/08/12 22:57:50
> > @@ -165,5 +165,7 @@
> >  	 * XXX Compatibility: programs using raw IP expect ip_len
> > -	 * XXX to have the header length subtracted.
> > +	 * XXX to have the header length subtracted, and in host order.
> > +	 * XXX ip_off is also expected to be host order.
> >  	 */
> > -	ip->ip_len -= ip->ip_hl << 2;
> > +	ip->ip_len = ntohs(ip->ip_len) - (ip->ip_hl << 2);
> > +	NTOHS(ip->ip_off);
>You're converting from host-to-net, so use htons() and HTONS(), right?

	no, this is in rip_input, so net-to-host.

itojun