/*      $NetBSD: route6.c,v 1.25 2018/02/01 16:23:28 maxv Exp $ */
/*      $KAME: route6.c,v 1.22 2000/12/03 00:54:00 itojun Exp $ */

/*
* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
* 3. Neither the name of the project nor the names of its contributors
*    may be used to endorse or promote products derived from this software
*    without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: route6.c,v 1.25 2018/02/01 16:23:28 maxv Exp $");

#include <sys/param.h>
#include <sys/mbuf.h>
#include <sys/systm.h>

#include <net/if.h>

#include <netinet/in.h>
#include <netinet6/in6_var.h>
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet6/ip6_private.h>

#include <netinet/icmp6.h>

int
route6_input(struct mbuf **mp, int *offp, int proto)
{
       struct mbuf *m = *mp;
       struct ip6_rthdr *rh;
       int off = *offp, rhlen;

       IP6_EXTHDR_GET(rh, struct ip6_rthdr *, m, off, sizeof(*rh));
       if (rh == NULL) {
               IP6_STATINC(IP6_STAT_TOOSHORT);
               return IPPROTO_DONE;
       }

       switch (rh->ip6r_type) {
       case IPV6_RTHDR_TYPE_0:
               /*
                * RFC5095: RH0 must be treated as unrecognized.
                */
       default:
               /* unknown routing type */
               if (rh->ip6r_segleft == 0) {
                       rhlen = (rh->ip6r_len + 1) << 3;
                       break;  /* Final dst. Just ignore the header. */
               }
               IP6_STATINC(IP6_STAT_BADOPTIONS);
               icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER,
                   off + offsetof(struct ip6_rthdr, ip6r_type));
               return IPPROTO_DONE;
       }

       *offp += rhlen;
       return rh->ip6r_nxt;
}