xref: /freebsd/sys/netinet6/route6.c (revision c0020399a650364d0134f79f3fa319f84064372d)
1 /*-
2  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the project nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  *	$KAME: route6.c,v 1.24 2001/03/14 03:07:05 itojun Exp $
30  */
31 
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34 
35 #include "opt_inet.h"
36 #include "opt_inet6.h"
37 
38 #include <sys/param.h>
39 #include <sys/mbuf.h>
40 #include <sys/socket.h>
41 #include <sys/systm.h>
42 #include <sys/queue.h>
43 #include <sys/vimage.h>
44 
45 #include <net/if.h>
46 
47 #include <netinet/in.h>
48 #include <netinet6/in6_var.h>
49 #include <netinet/ip6.h>
50 #include <netinet6/ip6_var.h>
51 #include <netinet6/scope6_var.h>
52 
53 #include <netinet/icmp6.h>
54 #include <netinet6/vinet6.h>
55 
56 /*
57  * proto - is unused
58  */
59 
60 int
61 route6_input(struct mbuf **mp, int *offp, int proto)
62 {
63 	INIT_VNET_INET6(curvnet);
64 	struct ip6_hdr *ip6;
65 	struct mbuf *m = *mp;
66 	struct ip6_rthdr *rh;
67 	int off = *offp, rhlen;
68 	struct ip6aux *ip6a;
69 
70 	ip6a = ip6_findaux(m);
71 	if (ip6a) {
72 		/* XXX reject home-address option before rthdr */
73 		if (ip6a->ip6a_flags & IP6A_SWAP) {
74 			V_ip6stat.ip6s_badoptions++;
75 			m_freem(m);
76 			return IPPROTO_DONE;
77 		}
78 	}
79 
80 #ifndef PULLDOWN_TEST
81 	IP6_EXTHDR_CHECK(m, off, sizeof(*rh), IPPROTO_DONE);
82 	ip6 = mtod(m, struct ip6_hdr *);
83 	rh = (struct ip6_rthdr *)((caddr_t)ip6 + off);
84 #else
85 	ip6 = mtod(m, struct ip6_hdr *);
86 	IP6_EXTHDR_GET(rh, struct ip6_rthdr *, m, off, sizeof(*rh));
87 	if (rh == NULL) {
88 		V_ip6stat.ip6s_tooshort++;
89 		return IPPROTO_DONE;
90 	}
91 #endif
92 
93 	/*
94 	 * While this switch may look gratuitous, leave it in
95 	 * in favour of RH2 implementations, etc.
96 	 */
97 	switch (rh->ip6r_type) {
98 #ifndef BURN_BRIDGES
99 	case IPV6_RTHDR_TYPE_0:
100 		/*
101 		 * According to RFC 5095, 3.  Deprecation of RH0,
102 		 * we must handle RH0 like the default (unknown
103 		 * routing header type) case.
104 		 */
105 		/* FALLTHROUGH */
106 #endif
107 	default:
108 		/* Unknown routing header type. */
109 		if (rh->ip6r_segleft == 0) {
110 			rhlen = (rh->ip6r_len + 1) << 3;
111 			break;	/* Final dst. Just ignore the header. */
112 		}
113 		V_ip6stat.ip6s_badoptions++;
114 		icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER,
115 			    (caddr_t)&rh->ip6r_type - (caddr_t)ip6);
116 		return (IPPROTO_DONE);
117 	}
118 
119 	*offp += rhlen;
120 	return (rh->ip6r_nxt);
121 }
122