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>
39 #include <sys/systm.h>
40 #include <sys/socket.h>
41 #include <sys/sockio.h>
43 #include <sys/errno.h>
44 #include <sys/kernel.h>
45 #include <sys/queue.h>
46 #include <sys/syslog.h>
47 #include <sys/sysctl.h>
48 #include <sys/protosw.h>
49 #include <sys/malloc.h>
52 #include <net/route.h>
54 #include <netinet/in.h>
55 #include <netinet/in_systm.h>
57 #include <netinet/ip.h>
59 #include <netinet/ip_encap.h>
61 #include <netinet/ip6.h>
62 #include <netinet6/ip6_var.h>
63 #include <netinet6/in6_gif.h>
64 #include <netinet6/in6_var.h>
66 #include <netinet6/ip6protosw.h>
67 #include <netinet/ip_ecn.h>
69 #include <netinet6/ip6_ecn.h>
72 #include <net/if_gif.h>
74 VNET_DEFINE(int, ip6_gif_hlim) = GIF_HLIM;
75 #define V_ip6_gif_hlim VNET(ip6_gif_hlim)
77 SYSCTL_DECL(_net_inet6_ip6);
78 SYSCTL_VNET_INT(_net_inet6_ip6, IPV6CTL_GIF_HLIM, gifhlim, CTLFLAG_RW,
79 &VNET_NAME(ip6_gif_hlim), 0, "");
81 static int gif_validate6(const struct ip6_hdr *, struct gif_softc *,
84 extern struct domain inet6domain;
85 struct ip6protosw in6_gif_protosw = {
87 .pr_domain = &inet6domain,
88 .pr_protocol = 0, /* IPPROTO_IPV[46] */
89 .pr_flags = PR_ATOMIC|PR_ADDR,
90 .pr_input = in6_gif_input,
91 .pr_output = rip6_output,
92 .pr_ctloutput = rip6_ctloutput,
93 .pr_usrreqs = &rip6_usrreqs
97 in6_gif_output(struct ifnet *ifp,
98 int family, /* family of the packet to be encapsulate */
101 struct gif_softc *sc = ifp->if_softc;
102 struct sockaddr_in6 *dst = (struct sockaddr_in6 *)&sc->gif_ro6.ro_dst;
103 struct sockaddr_in6 *sin6_src = (struct sockaddr_in6 *)sc->gif_psrc;
104 struct sockaddr_in6 *sin6_dst = (struct sockaddr_in6 *)sc->gif_pdst;
106 struct etherip_header eiphdr;
107 int error, len, proto;
112 if (sin6_src == NULL || sin6_dst == NULL ||
113 sin6_src->sin6_family != AF_INET6 ||
114 sin6_dst->sin6_family != AF_INET6) {
125 proto = IPPROTO_IPV4;
126 if (m->m_len < sizeof(*ip)) {
127 m = m_pullup(m, sizeof(*ip));
131 ip = mtod(m, struct ip *);
140 proto = IPPROTO_IPV6;
141 if (m->m_len < sizeof(*ip6)) {
142 m = m_pullup(m, sizeof(*ip6));
146 ip6 = mtod(m, struct ip6_hdr *);
147 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
152 proto = IPPROTO_ETHERIP;
155 * GIF_SEND_REVETHIP (disabled by default) intentionally
156 * sends an EtherIP packet with revered version field in
157 * the header. This is a knob for backward compatibility
158 * with FreeBSD 7.2R or prior.
160 if ((sc->gif_options & GIF_SEND_REVETHIP)) {
162 eiphdr.eip_resvl = ETHERIP_VERSION;
163 eiphdr.eip_resvh = 0;
165 eiphdr.eip_ver = ETHERIP_VERSION;
166 eiphdr.eip_resvl = 0;
167 eiphdr.eip_resvh = 0;
169 /* prepend Ethernet-in-IP header */
170 M_PREPEND(m, sizeof(struct etherip_header), M_DONTWAIT);
171 if (m && m->m_len < sizeof(struct etherip_header))
172 m = m_pullup(m, sizeof(struct etherip_header));
175 bcopy(&eiphdr, mtod(m, struct etherip_header *),
176 sizeof(struct etherip_header));
181 printf("in6_gif_output: warning: unknown family %d passed\n",
188 /* prepend new IP header */
189 len = sizeof(struct ip6_hdr);
190 #ifndef __NO_STRICT_ALIGNMENT
191 if (family == AF_LINK)
192 len += ETHERIP_ALIGN;
194 M_PREPEND(m, len, M_DONTWAIT);
195 if (m != NULL && m->m_len < len)
196 m = m_pullup(m, len);
198 printf("ENOBUFS in in6_gif_output %d\n", __LINE__);
201 #ifndef __NO_STRICT_ALIGNMENT
202 if (family == AF_LINK) {
203 len = mtod(m, vm_offset_t) & 3;
204 KASSERT(len == 0 || len == ETHERIP_ALIGN,
205 ("in6_gif_output: unexpected misalignment"));
207 m->m_len -= ETHERIP_ALIGN;
211 ip6 = mtod(m, struct ip6_hdr *);
213 ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
214 ip6->ip6_vfc |= IPV6_VERSION;
215 ip6->ip6_plen = htons((u_short)m->m_pkthdr.len);
216 ip6->ip6_nxt = proto;
217 ip6->ip6_hlim = V_ip6_gif_hlim;
218 ip6->ip6_src = sin6_src->sin6_addr;
219 /* bidirectional configured tunnel mode */
220 if (!IN6_IS_ADDR_UNSPECIFIED(&sin6_dst->sin6_addr))
221 ip6->ip6_dst = sin6_dst->sin6_addr;
226 ip_ecn_ingress((ifp->if_flags & IFF_LINK1) ? ECN_ALLOWED : ECN_NOCARE,
228 ip6->ip6_flow &= ~htonl(0xff << 20);
229 ip6->ip6_flow |= htonl((u_int32_t)otos << 20);
231 if (dst->sin6_family != sin6_dst->sin6_family ||
232 !IN6_ARE_ADDR_EQUAL(&dst->sin6_addr, &sin6_dst->sin6_addr)) {
233 /* cache route doesn't match */
234 bzero(dst, sizeof(*dst));
235 dst->sin6_family = sin6_dst->sin6_family;
236 dst->sin6_len = sizeof(struct sockaddr_in6);
237 dst->sin6_addr = sin6_dst->sin6_addr;
238 if (sc->gif_ro6.ro_rt) {
239 RTFREE(sc->gif_ro6.ro_rt);
240 sc->gif_ro6.ro_rt = NULL;
243 GIF2IFP(sc)->if_mtu = GIF_MTU;
247 if (sc->gif_ro6.ro_rt == NULL) {
248 rtalloc((struct route *)&sc->gif_ro6);
249 if (sc->gif_ro6.ro_rt == NULL) {
254 /* if it constitutes infinite encapsulation, punt. */
255 if (sc->gif_ro.ro_rt->rt_ifp == ifp) {
257 return ENETUNREACH; /*XXX*/
260 ifp->if_mtu = sc->gif_ro6.ro_rt->rt_ifp->if_mtu
261 - sizeof(struct ip6_hdr);
267 * force fragmentation to minimum MTU, to avoid path MTU discovery.
268 * it is too painful to ask for resend of inner packet, to achieve
269 * path MTU discovery for encapsulated packets.
271 error = ip6_output(m, 0, &sc->gif_ro6, IPV6_MINMTU, 0, NULL, NULL);
273 error = ip6_output(m, 0, &sc->gif_ro6, 0, 0, NULL, NULL);
276 if (!(GIF2IFP(sc)->if_flags & IFF_LINK0) &&
277 sc->gif_ro6.ro_rt != NULL) {
278 RTFREE(sc->gif_ro6.ro_rt);
279 sc->gif_ro6.ro_rt = NULL;
286 in6_gif_input(struct mbuf **mp, int *offp, int proto)
288 struct mbuf *m = *mp;
289 struct ifnet *gifp = NULL;
290 struct gif_softc *sc;
295 ip6 = mtod(m, struct ip6_hdr *);
297 sc = (struct gif_softc *)encap_getarg(m);
300 V_ip6stat.ip6s_nogif++;
305 if (gifp == NULL || (gifp->if_flags & IFF_UP) == 0) {
307 V_ip6stat.ip6s_nogif++;
311 otos = ip6->ip6_flow;
321 otos8 = (ntohl(otos) >> 20) & 0xff;
322 if (m->m_len < sizeof(*ip)) {
323 m = m_pullup(m, sizeof(*ip));
327 ip = mtod(m, struct ip *);
328 if (ip_ecn_egress((gifp->if_flags & IFF_LINK1) ?
329 ECN_ALLOWED : ECN_NOCARE,
330 &otos8, &ip->ip_tos) == 0) {
342 if (m->m_len < sizeof(*ip6)) {
343 m = m_pullup(m, sizeof(*ip6));
347 ip6 = mtod(m, struct ip6_hdr *);
348 if (ip6_ecn_egress((gifp->if_flags & IFF_LINK1) ?
349 ECN_ALLOWED : ECN_NOCARE,
350 &otos, &ip6->ip6_flow) == 0) {
357 case IPPROTO_ETHERIP:
362 V_ip6stat.ip6s_nogif++;
367 gif_input(m, af, gifp);
372 * validate outer address.
375 gif_validate6(const struct ip6_hdr *ip6, struct gif_softc *sc,
378 struct sockaddr_in6 *src, *dst;
380 src = (struct sockaddr_in6 *)sc->gif_psrc;
381 dst = (struct sockaddr_in6 *)sc->gif_pdst;
384 * Check for address match. Note that the check is for an incoming
385 * packet. We should compare the *source* address in our configuration
386 * and the *destination* address of the packet, and vice versa.
388 if (!IN6_ARE_ADDR_EQUAL(&src->sin6_addr, &ip6->ip6_dst) ||
389 !IN6_ARE_ADDR_EQUAL(&dst->sin6_addr, &ip6->ip6_src))
392 /* martian filters on outer source - done in ip6_input */
394 /* ingress filters on outer source */
395 if ((GIF2IFP(sc)->if_flags & IFF_LINK2) == 0 && ifp) {
396 struct sockaddr_in6 sin6;
399 bzero(&sin6, sizeof(sin6));
400 sin6.sin6_family = AF_INET6;
401 sin6.sin6_len = sizeof(struct sockaddr_in6);
402 sin6.sin6_addr = ip6->ip6_src;
403 sin6.sin6_scope_id = 0; /* XXX */
405 rt = rtalloc1((struct sockaddr *)&sin6, 0, 0UL);
406 if (!rt || rt->rt_ifp != ifp) {
408 char ip6buf[INET6_ADDRSTRLEN];
409 log(LOG_WARNING, "%s: packet from %s dropped "
410 "due to ingress filter\n", if_name(GIF2IFP(sc)),
411 ip6_sprintf(ip6buf, &sin6.sin6_addr));
424 * we know that we are in IFF_UP, outer address available, and outer family
425 * matched the physical addr family. see gif_encapcheck().
426 * sanity check for arg should have been done in the caller.
429 gif_encapcheck6(const struct mbuf *m, int off, int proto, void *arg)
432 struct gif_softc *sc;
435 /* sanity check done in caller */
436 sc = (struct gif_softc *)arg;
438 /* LINTED const cast */
439 m_copydata(m, 0, sizeof(ip6), (caddr_t)&ip6);
440 ifp = ((m->m_flags & M_PKTHDR) != 0) ? m->m_pkthdr.rcvif : NULL;
442 return gif_validate6(&ip6, sc, ifp);
446 in6_gif_attach(struct gif_softc *sc)
448 sc->encap_cookie6 = encap_attach_func(AF_INET6, -1, gif_encapcheck,
449 (void *)&in6_gif_protosw, sc);
450 if (sc->encap_cookie6 == NULL)
456 in6_gif_detach(struct gif_softc *sc)
460 error = encap_detach(sc->encap_cookie6);
462 sc->encap_cookie6 = NULL;