2 /* $KAME: in_gif.c,v 1.54 2001/05/14 14:02:16 itojun Exp $ */
5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
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.
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
33 #include "opt_mrouting.h"
35 #include "opt_inet6.h"
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/socket.h>
40 #include <sys/sockio.h>
42 #include <sys/errno.h>
43 #include <sys/kernel.h>
44 #include <sys/sysctl.h>
45 #include <sys/protosw.h>
47 #include <sys/malloc.h>
50 #include <net/route.h>
52 #include <netinet/in.h>
53 #include <netinet/in_systm.h>
54 #include <netinet/ip.h>
55 #include <netinet/ip_var.h>
56 #include <netinet/in_gif.h>
57 #include <netinet/in_var.h>
58 #include <netinet/ip_encap.h>
59 #include <netinet/ip_ecn.h>
62 #include <netinet/ip6.h>
66 #include <netinet/ip_mroute.h>
69 #include <net/if_gif.h>
71 #include <net/net_osdep.h>
73 static int gif_validate4(const struct ip *, struct gif_softc *,
76 extern struct domain inetdomain;
77 struct protosw in_gif_protosw = {
79 .pr_domain = &inetdomain,
80 .pr_protocol = 0/* IPPROTO_IPV[46] */,
81 .pr_flags = PR_ATOMIC|PR_ADDR,
82 .pr_input = in_gif_input,
83 .pr_output = (pr_output_t*)rip_output,
84 .pr_ctloutput = rip_ctloutput,
85 .pr_usrreqs = &rip_usrreqs
88 static int ip_gif_ttl = GIF_TTL;
89 SYSCTL_INT(_net_inet_ip, IPCTL_GIF_TTL, gifttl, CTLFLAG_RW,
93 in_gif_output(ifp, family, m)
98 struct gif_softc *sc = ifp->if_softc;
99 struct sockaddr_in *dst = (struct sockaddr_in *)&sc->gif_ro.ro_dst;
100 struct sockaddr_in *sin_src = (struct sockaddr_in *)sc->gif_psrc;
101 struct sockaddr_in *sin_dst = (struct sockaddr_in *)sc->gif_pdst;
102 struct ip iphdr; /* capsule IP header, host byte ordered */
103 struct etherip_header eiphdr;
109 if (sin_src == NULL || sin_dst == NULL ||
110 sin_src->sin_family != AF_INET ||
111 sin_dst->sin_family != AF_INET) {
122 proto = IPPROTO_IPV4;
123 if (m->m_len < sizeof(*ip)) {
124 m = m_pullup(m, sizeof(*ip));
128 ip = mtod(m, struct ip *);
137 proto = IPPROTO_IPV6;
138 if (m->m_len < sizeof(*ip6)) {
139 m = m_pullup(m, sizeof(*ip6));
143 ip6 = mtod(m, struct ip6_hdr *);
144 tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
149 proto = IPPROTO_ETHERIP;
150 eiphdr.eip_ver = ETHERIP_VERSION & ETHERIP_VER_VERS_MASK;
152 /* prepend Ethernet-in-IP header */
153 M_PREPEND(m, sizeof(struct etherip_header), M_DONTWAIT);
154 if (m && m->m_len < sizeof(struct etherip_header))
155 m = m_pullup(m, sizeof(struct etherip_header));
158 bcopy(&eiphdr, mtod(m, struct etherip_header *),
159 sizeof(struct etherip_header));
164 printf("in_gif_output: warning: unknown family %d passed\n",
171 bzero(&iphdr, sizeof(iphdr));
172 iphdr.ip_src = sin_src->sin_addr;
173 /* bidirectional configured tunnel mode */
174 if (sin_dst->sin_addr.s_addr != INADDR_ANY)
175 iphdr.ip_dst = sin_dst->sin_addr;
181 /* version will be set in ip_output() */
182 iphdr.ip_ttl = ip_gif_ttl;
183 iphdr.ip_len = m->m_pkthdr.len + sizeof(struct ip);
184 ip_ecn_ingress((ifp->if_flags & IFF_LINK1) ? ECN_ALLOWED : ECN_NOCARE,
185 &iphdr.ip_tos, &tos);
187 /* prepend new IP header */
188 M_PREPEND(m, sizeof(struct ip), M_DONTWAIT);
189 if (m && m->m_len < sizeof(struct ip))
190 m = m_pullup(m, sizeof(struct ip));
192 printf("ENOBUFS in in_gif_output %d\n", __LINE__);
195 bcopy(&iphdr, mtod(m, struct ip *), sizeof(struct ip));
197 if (dst->sin_family != sin_dst->sin_family ||
198 dst->sin_addr.s_addr != sin_dst->sin_addr.s_addr) {
199 /* cache route doesn't match */
200 bzero(dst, sizeof(*dst));
201 dst->sin_family = sin_dst->sin_family;
202 dst->sin_len = sizeof(struct sockaddr_in);
203 dst->sin_addr = sin_dst->sin_addr;
204 if (sc->gif_ro.ro_rt) {
205 RTFREE(sc->gif_ro.ro_rt);
206 sc->gif_ro.ro_rt = NULL;
209 GIF2IFP(sc)->if_mtu = GIF_MTU;
213 if (sc->gif_ro.ro_rt == NULL) {
214 rtalloc_ign(&sc->gif_ro, 0);
215 if (sc->gif_ro.ro_rt == NULL) {
220 /* if it constitutes infinite encapsulation, punt. */
221 if (sc->gif_ro.ro_rt->rt_ifp == ifp) {
223 return ENETUNREACH; /* XXX */
226 ifp->if_mtu = sc->gif_ro.ro_rt->rt_ifp->if_mtu
231 error = ip_output(m, NULL, &sc->gif_ro, 0, NULL, NULL);
233 if (!(GIF2IFP(sc)->if_flags & IFF_LINK0) &&
234 sc->gif_ro.ro_rt != NULL) {
235 RTFREE(sc->gif_ro.ro_rt);
236 sc->gif_ro.ro_rt = NULL;
247 struct ifnet *gifp = NULL;
248 struct gif_softc *sc;
254 ip = mtod(m, struct ip *);
257 sc = (struct gif_softc *)encap_getarg(m);
265 if (gifp == NULL || (gifp->if_flags & IFF_UP) == 0) {
280 if (m->m_len < sizeof(*ip)) {
281 m = m_pullup(m, sizeof(*ip));
285 ip = mtod(m, struct ip *);
286 if (ip_ecn_egress((gifp->if_flags & IFF_LINK1) ?
287 ECN_ALLOWED : ECN_NOCARE,
288 &otos, &ip->ip_tos) == 0) {
299 u_int8_t itos, oitos;
302 if (m->m_len < sizeof(*ip6)) {
303 m = m_pullup(m, sizeof(*ip6));
307 ip6 = mtod(m, struct ip6_hdr *);
308 itos = oitos = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
309 if (ip_ecn_egress((gifp->if_flags & IFF_LINK1) ?
310 ECN_ALLOWED : ECN_NOCARE,
311 &otos, &itos) == 0) {
316 ip6->ip6_flow &= ~htonl(0xff << 20);
317 ip6->ip6_flow |= htonl((u_int32_t)itos << 20);
322 case IPPROTO_ETHERIP:
331 gif_input(m, af, gifp);
336 * validate outer address.
339 gif_validate4(ip, sc, ifp)
341 struct gif_softc *sc;
344 struct sockaddr_in *src, *dst;
345 struct in_ifaddr *ia4;
347 src = (struct sockaddr_in *)sc->gif_psrc;
348 dst = (struct sockaddr_in *)sc->gif_pdst;
350 /* check for address match */
351 if (src->sin_addr.s_addr != ip->ip_dst.s_addr ||
352 dst->sin_addr.s_addr != ip->ip_src.s_addr)
355 /* martian filters on outer source - NOT done in ip_input! */
356 if (IN_MULTICAST(ntohl(ip->ip_src.s_addr)))
358 switch ((ntohl(ip->ip_src.s_addr) & 0xff000000) >> 24) {
359 case 0: case 127: case 255:
362 /* reject packets with broadcast on source */
363 TAILQ_FOREACH(ia4, &in_ifaddrhead, ia_link) {
364 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0)
366 if (ip->ip_src.s_addr == ia4->ia_broadaddr.sin_addr.s_addr)
370 /* ingress filters on outer source */
371 if ((GIF2IFP(sc)->if_flags & IFF_LINK2) == 0 && ifp) {
372 struct sockaddr_in sin;
375 bzero(&sin, sizeof(sin));
376 sin.sin_family = AF_INET;
377 sin.sin_len = sizeof(struct sockaddr_in);
378 sin.sin_addr = ip->ip_src;
379 rt = rtalloc1((struct sockaddr *)&sin, 0, 0UL);
380 if (!rt || rt->rt_ifp != ifp) {
382 log(LOG_WARNING, "%s: packet from 0x%x dropped "
383 "due to ingress filter\n", if_name(GIF2IFP(sc)),
384 (u_int32_t)ntohl(sin.sin_addr.s_addr));
397 * we know that we are in IFF_UP, outer address available, and outer family
398 * matched the physical addr family. see gif_encapcheck().
401 gif_encapcheck4(m, off, proto, arg)
402 const struct mbuf *m;
408 struct gif_softc *sc;
411 /* sanity check done in caller */
412 sc = (struct gif_softc *)arg;
414 /* LINTED const cast */
415 m_copydata(m, 0, sizeof(ip), (caddr_t)&ip);
416 ifp = ((m->m_flags & M_PKTHDR) != 0) ? m->m_pkthdr.rcvif : NULL;
418 return gif_validate4(&ip, sc, ifp);
423 struct gif_softc *sc;
425 sc->encap_cookie4 = encap_attach_func(AF_INET, -1, gif_encapcheck,
426 &in_gif_protosw, sc);
427 if (sc->encap_cookie4 == NULL)
434 struct gif_softc *sc;
438 error = encap_detach(sc->encap_cookie4);
440 sc->encap_cookie4 = NULL;