2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
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.
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
31 * $KAME: in6_gif.c,v 1.49 2001/05/14 14:02:17 itojun Exp $
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
38 #include "opt_inet6.h"
40 #include <sys/param.h>
42 #include <sys/rmlock.h>
43 #include <sys/systm.h>
44 #include <sys/socket.h>
45 #include <sys/sockio.h>
47 #include <sys/errno.h>
48 #include <sys/kernel.h>
49 #include <sys/queue.h>
50 #include <sys/syslog.h>
51 #include <sys/sysctl.h>
52 #include <sys/protosw.h>
53 #include <sys/malloc.h>
56 #include <net/if_var.h>
57 #include <net/route.h>
60 #include <netinet/in.h>
61 #include <netinet/in_systm.h>
63 #include <netinet/ip.h>
65 #include <netinet/ip_encap.h>
67 #include <netinet/ip6.h>
68 #include <netinet6/ip6_var.h>
69 #include <netinet6/in6_var.h>
71 #include <netinet/ip_ecn.h>
73 #include <netinet6/ip6_ecn.h>
74 #include <netinet6/in6_fib.h>
77 #include <net/if_gif.h>
80 static VNET_DEFINE(int, ip6_gif_hlim) = GIF_HLIM;
81 #define V_ip6_gif_hlim VNET(ip6_gif_hlim)
83 SYSCTL_DECL(_net_inet6_ip6);
84 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_GIF_HLIM, gifhlim, CTLFLAG_VNET | CTLFLAG_RW,
85 &VNET_NAME(ip6_gif_hlim), 0, "");
87 static int in6_gif_input(struct mbuf **, int *, int);
89 extern struct domain inet6domain;
90 static struct protosw in6_gif_protosw = {
92 .pr_domain = &inet6domain,
93 .pr_protocol = 0, /* IPPROTO_IPV[46] */
94 .pr_flags = PR_ATOMIC|PR_ADDR,
95 .pr_input = in6_gif_input,
96 .pr_output = rip6_output,
97 .pr_ctloutput = rip6_ctloutput,
98 .pr_usrreqs = &rip6_usrreqs
102 in6_gif_output(struct ifnet *ifp, struct mbuf *m, int proto, uint8_t ecn)
105 struct gif_softc *sc = ifp->if_softc;
109 /* prepend new IP header */
110 len = sizeof(struct ip6_hdr);
111 #ifndef __NO_STRICT_ALIGNMENT
112 if (proto == IPPROTO_ETHERIP)
113 len += ETHERIP_ALIGN;
115 M_PREPEND(m, len, M_NOWAIT);
118 #ifndef __NO_STRICT_ALIGNMENT
119 if (proto == IPPROTO_ETHERIP) {
120 len = mtod(m, vm_offset_t) & 3;
121 KASSERT(len == 0 || len == ETHERIP_ALIGN,
122 ("in6_gif_output: unexpected misalignment"));
124 m->m_len -= ETHERIP_ALIGN;
128 ip6 = mtod(m, struct ip6_hdr *);
130 if (sc->gif_family != AF_INET6) {
135 bcopy(sc->gif_ip6hdr, ip6, sizeof(struct ip6_hdr));
138 ip6->ip6_flow |= htonl((uint32_t)ecn << 20);
139 ip6->ip6_nxt = proto;
140 ip6->ip6_hlim = V_ip6_gif_hlim;
142 * force fragmentation to minimum MTU, to avoid path MTU discovery.
143 * it is too painful to ask for resend of inner packet, to achieve
144 * path MTU discovery for encapsulated packets.
146 return (ip6_output(m, 0, NULL, IPV6_MINMTU, 0, NULL, NULL));
150 in6_gif_input(struct mbuf **mp, int *offp, int proto)
152 struct mbuf *m = *mp;
154 struct gif_softc *sc;
158 sc = encap_getarg(m);
161 IP6STAT_INC(ip6s_nogif);
162 return (IPPROTO_DONE);
165 if ((gifp->if_flags & IFF_UP) != 0) {
166 ip6 = mtod(m, struct ip6_hdr *);
167 ecn = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
169 gif_input(m, gifp, proto, ecn);
172 IP6STAT_INC(ip6s_nogif);
174 return (IPPROTO_DONE);
178 * we know that we are in IFF_UP, outer address available, and outer family
179 * matched the physical addr family. see gif_encapcheck().
182 in6_gif_encapcheck(const struct mbuf *m, int off, int proto, void *arg)
184 const struct ip6_hdr *ip6;
185 struct gif_softc *sc;
188 /* sanity check done in caller */
189 sc = (struct gif_softc *)arg;
190 GIF_RLOCK_ASSERT(sc);
193 * Check for address match. Note that the check is for an incoming
194 * packet. We should compare the *source* address in our configuration
195 * and the *destination* address of the packet, and vice versa.
197 ip6 = mtod(m, const struct ip6_hdr *);
198 if (!IN6_ARE_ADDR_EQUAL(&sc->gif_ip6hdr->ip6_src, &ip6->ip6_dst))
201 if (!IN6_ARE_ADDR_EQUAL(&sc->gif_ip6hdr->ip6_dst, &ip6->ip6_src)) {
202 if ((sc->gif_options & GIF_IGNORE_SOURCE) == 0)
207 /* ingress filters on outer source */
208 if ((GIF2IFP(sc)->if_flags & IFF_LINK2) == 0) {
209 struct nhop6_basic nh6;
211 /* XXX empty scope id */
212 if (fib6_lookup_nh_basic(sc->gif_fibnum, &ip6->ip6_src, 0, 0, 0,
216 if (nh6.nh_ifp != m->m_pkthdr.rcvif)
223 in6_gif_attach(struct gif_softc *sc)
226 KASSERT(sc->gif_ecookie == NULL, ("gif_ecookie isn't NULL"));
227 sc->gif_ecookie = encap_attach_func(AF_INET6, -1, gif_encapcheck,
228 (void *)&in6_gif_protosw, sc);
229 if (sc->gif_ecookie == NULL)