1 /* $KAME: in_gif.c,v 1.54 2001/05/14 14:02:16 itojun Exp $ */
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
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
35 #include "opt_mrouting.h"
37 #include "opt_inet6.h"
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/socket.h>
42 #include <sys/sockio.h>
44 #include <sys/errno.h>
45 #include <sys/kernel.h>
46 #include <sys/sysctl.h>
47 #include <sys/protosw.h>
48 #include <sys/malloc.h>
51 #include <net/route.h>
54 #include <netinet/in.h>
55 #include <netinet/in_systm.h>
56 #include <netinet/ip.h>
57 #include <netinet/ip_var.h>
58 #include <netinet/in_gif.h>
59 #include <netinet/in_var.h>
60 #include <netinet/ip_encap.h>
61 #include <netinet/ip_ecn.h>
64 #include <netinet/ip6.h>
68 #include <netinet/ip_mroute.h>
71 #include <net/if_gif.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 SYSCTL_VNET_INT(_net_inet_ip, IPCTL_GIF_TTL, gifttl, CTLFLAG_RW,
89 &VNET_NAME(ip_gif_ttl), 0, "");
92 in_gif_output(struct ifnet *ifp, int family, struct mbuf *m)
94 struct gif_softc *sc = ifp->if_softc;
95 struct sockaddr_in *dst = (struct sockaddr_in *)&sc->gif_ro.ro_dst;
96 struct sockaddr_in *sin_src = (struct sockaddr_in *)sc->gif_psrc;
97 struct sockaddr_in *sin_dst = (struct sockaddr_in *)sc->gif_pdst;
98 struct ip iphdr; /* capsule IP header, host byte ordered */
99 struct etherip_header eiphdr;
100 int error, len, proto;
105 if (sin_src == NULL || sin_dst == NULL ||
106 sin_src->sin_family != AF_INET ||
107 sin_dst->sin_family != AF_INET) {
118 proto = IPPROTO_IPV4;
119 if (m->m_len < sizeof(*ip)) {
120 m = m_pullup(m, sizeof(*ip));
124 ip = mtod(m, struct ip *);
133 proto = IPPROTO_IPV6;
134 if (m->m_len < sizeof(*ip6)) {
135 m = m_pullup(m, sizeof(*ip6));
139 ip6 = mtod(m, struct ip6_hdr *);
140 tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
145 proto = IPPROTO_ETHERIP;
148 * GIF_SEND_REVETHIP (disabled by default) intentionally
149 * sends an EtherIP packet with revered version field in
150 * the header. This is a knob for backward compatibility
151 * with FreeBSD 7.2R or prior.
153 if ((sc->gif_options & GIF_SEND_REVETHIP)) {
155 eiphdr.eip_resvl = ETHERIP_VERSION;
156 eiphdr.eip_resvh = 0;
158 eiphdr.eip_ver = ETHERIP_VERSION;
159 eiphdr.eip_resvl = 0;
160 eiphdr.eip_resvh = 0;
162 /* prepend Ethernet-in-IP header */
163 M_PREPEND(m, sizeof(struct etherip_header), M_DONTWAIT);
164 if (m && m->m_len < sizeof(struct etherip_header))
165 m = m_pullup(m, sizeof(struct etherip_header));
168 bcopy(&eiphdr, mtod(m, struct etherip_header *),
169 sizeof(struct etherip_header));
174 printf("in_gif_output: warning: unknown family %d passed\n",
181 bzero(&iphdr, sizeof(iphdr));
182 iphdr.ip_src = sin_src->sin_addr;
183 /* bidirectional configured tunnel mode */
184 if (sin_dst->sin_addr.s_addr != INADDR_ANY)
185 iphdr.ip_dst = sin_dst->sin_addr;
191 /* version will be set in ip_output() */
192 iphdr.ip_ttl = V_ip_gif_ttl;
193 iphdr.ip_len = m->m_pkthdr.len + sizeof(struct ip);
194 ip_ecn_ingress((ifp->if_flags & IFF_LINK1) ? ECN_ALLOWED : ECN_NOCARE,
195 &iphdr.ip_tos, &tos);
197 /* prepend new IP header */
198 len = sizeof(struct ip);
199 #ifndef __NO_STRICT_ALIGNMENT
200 if (family == AF_LINK)
201 len += ETHERIP_ALIGN;
203 M_PREPEND(m, len, M_DONTWAIT);
204 if (m != NULL && m->m_len < len)
205 m = m_pullup(m, len);
207 printf("ENOBUFS in in_gif_output %d\n", __LINE__);
210 #ifndef __NO_STRICT_ALIGNMENT
211 if (family == AF_LINK) {
212 len = mtod(m, vm_offset_t) & 3;
213 KASSERT(len == 0 || len == ETHERIP_ALIGN,
214 ("in_gif_output: unexpected misalignment"));
216 m->m_len -= ETHERIP_ALIGN;
219 bcopy(&iphdr, mtod(m, struct ip *), sizeof(struct ip));
221 M_SETFIB(m, sc->gif_fibnum);
223 if (dst->sin_family != sin_dst->sin_family ||
224 dst->sin_addr.s_addr != sin_dst->sin_addr.s_addr) {
225 /* cache route doesn't match */
226 bzero(dst, sizeof(*dst));
227 dst->sin_family = sin_dst->sin_family;
228 dst->sin_len = sizeof(struct sockaddr_in);
229 dst->sin_addr = sin_dst->sin_addr;
230 if (sc->gif_ro.ro_rt) {
231 RTFREE(sc->gif_ro.ro_rt);
232 sc->gif_ro.ro_rt = NULL;
235 GIF2IFP(sc)->if_mtu = GIF_MTU;
239 if (sc->gif_ro.ro_rt == NULL) {
240 in_rtalloc_ign(&sc->gif_ro, 0, sc->gif_fibnum);
241 if (sc->gif_ro.ro_rt == NULL) {
246 /* if it constitutes infinite encapsulation, punt. */
247 if (sc->gif_ro.ro_rt->rt_ifp == ifp) {
249 return ENETUNREACH; /* XXX */
252 ifp->if_mtu = sc->gif_ro.ro_rt->rt_ifp->if_mtu
257 error = ip_output(m, NULL, &sc->gif_ro, 0, NULL, NULL);
259 if (!(GIF2IFP(sc)->if_flags & IFF_LINK0) &&
260 sc->gif_ro.ro_rt != NULL) {
261 RTFREE(sc->gif_ro.ro_rt);
262 sc->gif_ro.ro_rt = NULL;
269 in_gif_input(struct mbuf *m, int off)
271 struct ifnet *gifp = NULL;
272 struct gif_softc *sc;
278 ip = mtod(m, struct ip *);
281 sc = (struct gif_softc *)encap_getarg(m);
284 KMOD_IPSTAT_INC(ips_nogif);
289 if (gifp == NULL || (gifp->if_flags & IFF_UP) == 0) {
291 KMOD_IPSTAT_INC(ips_nogif);
304 if (m->m_len < sizeof(*ip)) {
305 m = m_pullup(m, sizeof(*ip));
309 ip = mtod(m, struct ip *);
310 if (ip_ecn_egress((gifp->if_flags & IFF_LINK1) ?
311 ECN_ALLOWED : ECN_NOCARE,
312 &otos, &ip->ip_tos) == 0) {
323 u_int8_t itos, oitos;
326 if (m->m_len < sizeof(*ip6)) {
327 m = m_pullup(m, sizeof(*ip6));
331 ip6 = mtod(m, struct ip6_hdr *);
332 itos = oitos = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
333 if (ip_ecn_egress((gifp->if_flags & IFF_LINK1) ?
334 ECN_ALLOWED : ECN_NOCARE,
335 &otos, &itos) == 0) {
340 ip6->ip6_flow &= ~htonl(0xff << 20);
341 ip6->ip6_flow |= htonl((u_int32_t)itos << 20);
346 case IPPROTO_ETHERIP:
351 KMOD_IPSTAT_INC(ips_nogif);
355 gif_input(m, af, gifp);
360 * validate outer address.
363 gif_validate4(const struct ip *ip, struct gif_softc *sc, struct ifnet *ifp)
365 struct sockaddr_in *src, *dst;
366 struct in_ifaddr *ia4;
368 src = (struct sockaddr_in *)sc->gif_psrc;
369 dst = (struct sockaddr_in *)sc->gif_pdst;
371 /* check for address match */
372 if (src->sin_addr.s_addr != ip->ip_dst.s_addr ||
373 dst->sin_addr.s_addr != ip->ip_src.s_addr)
376 /* martian filters on outer source - NOT done in ip_input! */
377 if (IN_MULTICAST(ntohl(ip->ip_src.s_addr)))
379 switch ((ntohl(ip->ip_src.s_addr) & 0xff000000) >> 24) {
380 case 0: case 127: case 255:
384 /* reject packets with broadcast on source */
385 /* XXXRW: should use hash lists? */
387 TAILQ_FOREACH(ia4, &V_in_ifaddrhead, ia_link) {
388 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0)
390 if (ip->ip_src.s_addr == ia4->ia_broadaddr.sin_addr.s_addr) {
397 /* ingress filters on outer source */
398 if ((GIF2IFP(sc)->if_flags & IFF_LINK2) == 0 && ifp) {
399 struct sockaddr_in sin;
402 bzero(&sin, sizeof(sin));
403 sin.sin_family = AF_INET;
404 sin.sin_len = sizeof(struct sockaddr_in);
405 sin.sin_addr = ip->ip_src;
406 /* XXX MRT check for the interface we would use on output */
407 rt = in_rtalloc1((struct sockaddr *)&sin, 0,
408 0UL, sc->gif_fibnum);
409 if (!rt || rt->rt_ifp != ifp) {
411 log(LOG_WARNING, "%s: packet from 0x%x dropped "
412 "due to ingress filter\n", if_name(GIF2IFP(sc)),
413 (u_int32_t)ntohl(sin.sin_addr.s_addr));
426 * we know that we are in IFF_UP, outer address available, and outer family
427 * matched the physical addr family. see gif_encapcheck().
430 gif_encapcheck4(const struct mbuf *m, int off, int proto, void *arg)
433 struct gif_softc *sc;
436 /* sanity check done in caller */
437 sc = (struct gif_softc *)arg;
439 /* LINTED const cast */
440 m_copydata(m, 0, sizeof(ip), (caddr_t)&ip);
441 ifp = ((m->m_flags & M_PKTHDR) != 0) ? m->m_pkthdr.rcvif : NULL;
443 return gif_validate4(&ip, sc, ifp);
447 in_gif_attach(struct gif_softc *sc)
449 sc->encap_cookie4 = encap_attach_func(AF_INET, -1, gif_encapcheck,
450 &in_gif_protosw, sc);
451 if (sc->encap_cookie4 == NULL)
457 in_gif_detach(struct gif_softc *sc)
461 error = encap_detach(sc->encap_cookie4);
463 sc->encap_cookie4 = NULL;