xref: /openbsd/sys/netinet6/route6.c (revision d415bd75)
1 /*	$OpenBSD: route6.c,v 1.21 2017/04/14 20:46:31 bluhm Exp $	*/
2 /*	$KAME: route6.c,v 1.22 2000/12/03 00:54:00 itojun Exp $	*/
3 
4 /*
5  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the project nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #include <sys/param.h>
34 #include <sys/mbuf.h>
35 #include <sys/socket.h>
36 #include <sys/systm.h>
37 
38 #include <net/if.h>
39 #include <net/if_var.h>
40 
41 #include <netinet/in.h>
42 #include <netinet6/in6_var.h>
43 #include <netinet/ip6.h>
44 #include <netinet6/ip6_var.h>
45 
46 #include <netinet/icmp6.h>
47 
48 /*
49  * proto is unused
50  */
51 
52 int
53 route6_input(struct mbuf **mp, int *offp, int proto, int af)
54 {
55 	struct ip6_hdr *ip6;
56 	struct mbuf *m = *mp;
57 	struct ip6_rthdr *rh;
58 	int off = *offp, rhlen;
59 
60 	ip6 = mtod(m, struct ip6_hdr *);
61 	IP6_EXTHDR_GET(rh, struct ip6_rthdr *, m, off, sizeof(*rh));
62 	if (rh == NULL) {
63 		ip6stat_inc(ip6s_tooshort);
64 		return IPPROTO_DONE;
65 	}
66 
67 	switch (rh->ip6r_type) {
68 	case IPV6_RTHDR_TYPE_0:
69 		/*
70 		 * RFC 5095 specifies to handle routing header type 0
71 		 * the same way as an unrecognised routing type.
72 		 */
73 		/* FALLTHROUGH */
74 	default:
75 		/* unknown routing type */
76 		if (rh->ip6r_segleft == 0) {
77 			rhlen = (rh->ip6r_len + 1) << 3;
78 			break;	/* Final dst. Just ignore the header. */
79 		}
80 		ip6stat_inc(ip6s_badoptions);
81 		icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER,
82 			    (caddr_t)&rh->ip6r_type - (caddr_t)ip6);
83 		return (IPPROTO_DONE);
84 	}
85 
86 	*offp += rhlen;
87 	return (rh->ip6r_nxt);
88 }
89