Home | History | Annotate | Line # | Download | only in netinet6
dest6.c revision 1.4 
      1 /*	$NetBSD: dest6.c,v 1.4 1999/07/30 10:35:35 itojun Exp $	*/
      2 
      3 /*
      4  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
      5  * All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. Neither the name of the project nor the names of its contributors
     16  *    may be used to endorse or promote products derived from this software
     17  *    without specific prior written permission.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
     20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
     23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     29  * SUCH DAMAGE.
     30  */
     31 
     32 #include <sys/param.h>
     33 #include <sys/systm.h>
     34 #include <sys/malloc.h>
     35 #include <sys/mbuf.h>
     36 #include <sys/domain.h>
     37 #include <sys/protosw.h>
     38 #include <sys/socket.h>
     39 #include <sys/errno.h>
     40 #include <sys/time.h>
     41 #include <sys/kernel.h>
     42 
     43 #include <net/if.h>
     44 #include <net/route.h>
     45 
     46 #include <netinet/in.h>
     47 #include <netinet/in_var.h>
     48 #include <netinet6/ip6.h>
     49 #if !defined(__FreeBSD__) || __FreeBSD__ < 3
     50 #include <netinet6/in6_pcb.h>
     51 #endif
     52 #include <netinet6/ip6_var.h>
     53 #include <netinet6/icmp6.h>
     54 
     55 /*
     56  * Destination options header processing.
     57  */
     58 int
     59 dest6_input(mp, offp, proto)
     60 	struct mbuf **mp;
     61 	int *offp, proto;
     62 {
     63 	register struct mbuf *m = *mp;
     64 	int off = *offp, dstoptlen, optlen;
     65 	struct ip6_dest *dstopts;
     66 	u_int8_t *opt;
     67 
     68 	/* validation of the length of the header */
     69 	IP6_EXTHDR_CHECK(m, off, sizeof(*dstopts), IPPROTO_DONE);
     70 	dstopts = (struct ip6_dest *)(mtod(m, caddr_t) + off);
     71 	dstoptlen = (dstopts->ip6d_len + 1) << 3;
     72 
     73 	IP6_EXTHDR_CHECK(m, off, dstoptlen, IPPROTO_DONE);
     74 	dstopts = (struct ip6_dest *)(mtod(m, caddr_t) + off);
     75 	off += dstoptlen;
     76 	dstoptlen -= sizeof(struct ip6_dest);
     77 	opt = (u_int8_t *)dstopts + sizeof(struct ip6_dest);
     78 
     79 	/* search header for all options. */
     80 	for (optlen = 0; dstoptlen > 0; dstoptlen -= optlen, opt += optlen) {
     81 		switch(*opt) {
     82 		 case IP6OPT_PAD1:
     83 			 optlen = 1;
     84 			 break;
     85 		 case IP6OPT_PADN:
     86 			 if (dstoptlen < IP6OPT_MINLEN) {
     87 				 ip6stat.ip6s_toosmall++;
     88 				 goto bad;
     89 			 }
     90 			 optlen = *(opt + 1) + 2;
     91 			 break;
     92 		 default:		/* unknown option */
     93 			 if (dstoptlen < IP6OPT_MINLEN) {
     94 				 ip6stat.ip6s_toosmall++;
     95 				 goto bad;
     96 			 }
     97 			 if ((optlen = ip6_unknown_opt(opt, m,
     98 						       opt-mtod(m, u_int8_t *))) == -1)
     99 				 return(IPPROTO_DONE);
    100 			 optlen += 2;
    101 			 break;
    102 		}
    103 	}
    104 
    105 	*offp = off;
    106 	return(dstopts->ip6d_nxt);
    107 
    108   bad:
    109 	m_freem(m);
    110 	return(IPPROTO_DONE);
    111 }
    112