2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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
29 * $KAME: in6_gif.c,v 1.49 2001/05/14 14:02:17 itojun Exp $
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
36 #include "opt_inet6.h"
38 #include <sys/param.h>
40 #include <sys/rmlock.h>
41 #include <sys/systm.h>
42 #include <sys/socket.h>
43 #include <sys/sockio.h>
45 #include <sys/errno.h>
46 #include <sys/kernel.h>
47 #include <sys/queue.h>
48 #include <sys/syslog.h>
49 #include <sys/sysctl.h>
50 #include <sys/protosw.h>
51 #include <sys/malloc.h>
54 #include <net/if_var.h>
55 #include <net/route.h>
58 #include <netinet/in.h>
59 #include <netinet/in_systm.h>
61 #include <netinet/ip.h>
63 #include <netinet/ip_encap.h>
65 #include <netinet/ip6.h>
66 #include <netinet6/ip6_var.h>
67 #include <netinet6/in6_var.h>
69 #include <netinet/ip_ecn.h>
71 #include <netinet6/ip6_ecn.h>
74 #include <net/if_gif.h>
77 static VNET_DEFINE(int, ip6_gif_hlim) = GIF_HLIM;
78 #define V_ip6_gif_hlim VNET(ip6_gif_hlim)
80 SYSCTL_DECL(_net_inet6_ip6);
81 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_GIF_HLIM, gifhlim, CTLFLAG_VNET | CTLFLAG_RW,
82 &VNET_NAME(ip6_gif_hlim), 0, "");
84 int in6_gif_output(struct ifnet *, struct mbuf *, int, uint8_t);
85 int in6_gif_encapcheck(const struct mbuf *, int, int, void *);
86 int in6_gif_attach(struct gif_softc *);
88 static int gif_validate6(const struct ip6_hdr *, struct gif_softc *,
90 static int in6_gif_input(struct mbuf **, int *, int);
92 extern struct domain inet6domain;
93 static struct protosw in6_gif_protosw = {
95 .pr_domain = &inet6domain,
96 .pr_protocol = 0, /* IPPROTO_IPV[46] */
97 .pr_flags = PR_ATOMIC|PR_ADDR,
98 .pr_input = in6_gif_input,
99 .pr_output = rip6_output,
100 .pr_ctloutput = rip6_ctloutput,
101 .pr_usrreqs = &rip6_usrreqs
105 in6_gif_output(struct ifnet *ifp, struct mbuf *m, int proto, uint8_t ecn)
108 struct gif_softc *sc = ifp->if_softc;
112 /* prepend new IP header */
113 len = sizeof(struct ip6_hdr);
114 #ifndef __NO_STRICT_ALIGNMENT
115 if (proto == IPPROTO_ETHERIP)
116 len += ETHERIP_ALIGN;
118 M_PREPEND(m, len, M_NOWAIT);
121 #ifndef __NO_STRICT_ALIGNMENT
122 if (proto == IPPROTO_ETHERIP) {
123 len = mtod(m, vm_offset_t) & 3;
124 KASSERT(len == 0 || len == ETHERIP_ALIGN,
125 ("in6_gif_output: unexpected misalignment"));
127 m->m_len -= ETHERIP_ALIGN;
131 ip6 = mtod(m, struct ip6_hdr *);
133 if (sc->gif_family != AF_INET6) {
138 bcopy(sc->gif_ip6hdr, ip6, sizeof(struct ip6_hdr));
141 ip6->ip6_flow |= htonl((uint32_t)ecn << 20);
142 ip6->ip6_nxt = proto;
143 ip6->ip6_hlim = V_ip6_gif_hlim;
145 * force fragmentation to minimum MTU, to avoid path MTU discovery.
146 * it is too painful to ask for resend of inner packet, to achieve
147 * path MTU discovery for encapsulated packets.
149 return (ip6_output(m, 0, NULL, IPV6_MINMTU, 0, NULL, NULL));
153 in6_gif_input(struct mbuf **mp, int *offp, int proto)
155 struct mbuf *m = *mp;
157 struct gif_softc *sc;
161 sc = encap_getarg(m);
164 IP6STAT_INC(ip6s_nogif);
165 return (IPPROTO_DONE);
168 if ((gifp->if_flags & IFF_UP) != 0) {
169 ip6 = mtod(m, struct ip6_hdr *);
170 ecn = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
172 gif_input(m, gifp, proto, ecn);
175 IP6STAT_INC(ip6s_nogif);
177 return (IPPROTO_DONE);
181 * validate outer address.
184 gif_validate6(const struct ip6_hdr *ip6, struct gif_softc *sc,
188 GIF_RLOCK_ASSERT(sc);
190 * Check for address match. Note that the check is for an incoming
191 * packet. We should compare the *source* address in our configuration
192 * and the *destination* address of the packet, and vice versa.
194 if (!IN6_ARE_ADDR_EQUAL(&sc->gif_ip6hdr->ip6_src, &ip6->ip6_dst) ||
195 !IN6_ARE_ADDR_EQUAL(&sc->gif_ip6hdr->ip6_dst, &ip6->ip6_src))
198 /* martian filters on outer source - done in ip6_input */
200 /* ingress filters on outer source */
201 if ((GIF2IFP(sc)->if_flags & IFF_LINK2) == 0 && ifp) {
202 struct sockaddr_in6 sin6;
205 bzero(&sin6, sizeof(sin6));
206 sin6.sin6_family = AF_INET6;
207 sin6.sin6_len = sizeof(struct sockaddr_in6);
208 sin6.sin6_addr = ip6->ip6_src;
209 sin6.sin6_scope_id = 0; /* XXX */
211 rt = in6_rtalloc1((struct sockaddr *)&sin6, 0, 0UL,
213 if (!rt || rt->rt_ifp != ifp) {
225 * we know that we are in IFF_UP, outer address available, and outer family
226 * matched the physical addr family. see gif_encapcheck().
229 in6_gif_encapcheck(const struct mbuf *m, int off, int proto, void *arg)
232 struct gif_softc *sc;
235 /* sanity check done in caller */
236 sc = (struct gif_softc *)arg;
237 GIF_RLOCK_ASSERT(sc);
239 m_copydata(m, 0, sizeof(ip6), (caddr_t)&ip6);
240 ifp = ((m->m_flags & M_PKTHDR) != 0) ? m->m_pkthdr.rcvif : NULL;
241 return (gif_validate6(&ip6, sc, ifp));
245 in6_gif_attach(struct gif_softc *sc)
248 KASSERT(sc->gif_ecookie == NULL, ("gif_ecookie isn't NULL"));
249 sc->gif_ecookie = encap_attach_func(AF_INET6, -1, gif_encapcheck,
250 (void *)&in6_gif_protosw, sc);
251 if (sc->gif_ecookie == NULL)