xref: /freebsd/sys/netinet6/route6.c (revision d8a0fe102c0cfdfcd5b818f850eff09d8536c9bc)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
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  *	$KAME: route6.c,v 1.24 2001/03/14 03:07:05 itojun Exp $
32  */
33 
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
36 
37 #include "opt_inet.h"
38 #include "opt_inet6.h"
39 
40 #include <sys/param.h>
41 #include <sys/mbuf.h>
42 #include <sys/socket.h>
43 #include <sys/systm.h>
44 #include <sys/queue.h>
45 
46 #include <net/if.h>
47 #include <net/if_var.h>
48 
49 #include <netinet/in.h>
50 #include <netinet6/in6_var.h>
51 #include <netinet/ip6.h>
52 #include <netinet6/ip6_var.h>
53 #include <netinet6/scope6_var.h>
54 
55 #include <netinet/icmp6.h>
56 
57 /*
58  * proto - is unused
59  */
60 
61 int
62 route6_input(struct mbuf **mp, int *offp, int proto)
63 {
64 	struct ip6_hdr *ip6;
65 	struct mbuf *m = *mp;
66 	struct ip6_rthdr *rh;
67 	int off = *offp, rhlen;
68 #ifdef __notyet__
69 	struct ip6aux *ip6a;
70 
71 	ip6a = ip6_findaux(m);
72 	if (ip6a) {
73 		/* XXX reject home-address option before rthdr */
74 		if (ip6a->ip6a_flags & IP6A_SWAP) {
75 			IP6STAT_INC(ip6s_badoptions);
76 			m_freem(m);
77 			return IPPROTO_DONE;
78 		}
79 	}
80 #endif
81 
82 #ifndef PULLDOWN_TEST
83 	IP6_EXTHDR_CHECK(m, off, sizeof(*rh), IPPROTO_DONE);
84 	ip6 = mtod(m, struct ip6_hdr *);
85 	rh = (struct ip6_rthdr *)((caddr_t)ip6 + off);
86 #else
87 	ip6 = mtod(m, struct ip6_hdr *);
88 	IP6_EXTHDR_GET(rh, struct ip6_rthdr *, m, off, sizeof(*rh));
89 	if (rh == NULL) {
90 		IP6STAT_INC(ip6s_tooshort);
91 		return IPPROTO_DONE;
92 	}
93 #endif
94 
95 	/*
96 	 * While this switch may look gratuitous, leave it in
97 	 * in favour of RH2 implementations, etc.
98 	 */
99 	switch (rh->ip6r_type) {
100 	default:
101 		/* Unknown routing header type. */
102 		if (rh->ip6r_segleft == 0) {
103 			rhlen = (rh->ip6r_len + 1) << 3;
104 			break;	/* Final dst. Just ignore the header. */
105 		}
106 		IP6STAT_INC(ip6s_badoptions);
107 		icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER,
108 			    (caddr_t)&rh->ip6r_type - (caddr_t)ip6);
109 		return (IPPROTO_DONE);
110 	}
111 
112 	*offp += rhlen;
113 	return (rh->ip6r_nxt);
114 }
115