1/* $KAME: in_gif.c,v 1.54 2001/05/14 14:02:16 itojun Exp $ */
2
3/*-
4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
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.
18 *
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
29 * SUCH DAMAGE.
30 */
31
32#include <sys/cdefs.h>
33__FBSDID("$FreeBSD: head/sys/netinet/in_gif.c 196019 2009-08-01 19:26:27Z rwatson $");
34
35#include "opt_mrouting.h"
36#include "opt_inet.h"
37#include "opt_inet6.h"
38
39#include <sys/param.h>
40#include <sys/systm.h>
41#include <sys/socket.h>
42#include <sys/sockio.h>
43#include <sys/mbuf.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>
49
50#include <net/if.h>
51#include <net/route.h>
52#include <net/vnet.h>
53
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>
62
63#ifdef INET6
64#include <netinet/ip6.h>
65#endif
66
67#ifdef MROUTING
68#include <netinet/ip_mroute.h>
69#endif /* MROUTING */
70
71#include <net/if_gif.h>
72
73static int gif_validate4(const struct ip *, struct gif_softc *,
74 struct ifnet *);
75
76extern struct domain inetdomain;
77struct protosw in_gif_protosw = {
78 .pr_type = SOCK_RAW,
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
86};
87
88SYSCTL_VNET_INT(_net_inet_ip, IPCTL_GIF_TTL, gifttl, CTLFLAG_RW,
89 &VNET_NAME(ip_gif_ttl), 0, "");
90
91int
92in_gif_output(struct ifnet *ifp, int family, struct mbuf *m)
93{
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;
101 u_int8_t tos;
102
103 GIF_LOCK_ASSERT(sc);
104
105 if (sin_src == NULL || sin_dst == NULL ||
106 sin_src->sin_family != AF_INET ||
107 sin_dst->sin_family != AF_INET) {
108 m_freem(m);
109 return EAFNOSUPPORT;
110 }
111
112 switch (family) {
113#ifdef INET
114 case AF_INET:
115 {
116 struct ip *ip;
117
118 proto = IPPROTO_IPV4;
119 if (m->m_len < sizeof(*ip)) {
120 m = m_pullup(m, sizeof(*ip));
121 if (!m)
122 return ENOBUFS;
123 }
124 ip = mtod(m, struct ip *);
125 tos = ip->ip_tos;
126 break;
127 }
128#endif /* INET */
129#ifdef INET6
130 case AF_INET6:
131 {
132 struct ip6_hdr *ip6;
133 proto = IPPROTO_IPV6;
134 if (m->m_len < sizeof(*ip6)) {
135 m = m_pullup(m, sizeof(*ip6));
136 if (!m)
137 return ENOBUFS;
138 }
139 ip6 = mtod(m, struct ip6_hdr *);
140 tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
141 break;
142 }
143#endif /* INET6 */
144 case AF_LINK:
145 proto = IPPROTO_ETHERIP;
146
147 /*
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.
152 */
153 if ((sc->gif_options & GIF_SEND_REVETHIP)) {
154 eiphdr.eip_ver = 0;
155 eiphdr.eip_resvl = ETHERIP_VERSION;
156 eiphdr.eip_resvh = 0;
157 } else {
158 eiphdr.eip_ver = ETHERIP_VERSION;
159 eiphdr.eip_resvl = 0;
160 eiphdr.eip_resvh = 0;
161 }
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));
166 if (m == NULL)
167 return ENOBUFS;
168 bcopy(&eiphdr, mtod(m, struct etherip_header *),
169 sizeof(struct etherip_header));
170 break;
171
172 default:
173#ifdef DEBUG
174 printf("in_gif_output: warning: unknown family %d passed\n",
175 family);
176#endif
177 m_freem(m);
178 return EAFNOSUPPORT;
179 }
180
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;
186 else {
187 m_freem(m);
188 return ENETUNREACH;
189 }
190 iphdr.ip_p = proto;
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);
196
197 /* prepend new IP header */
198 len = sizeof(struct ip);
199#ifndef __NO_STRICT_ALIGNMENT
200 if (family == AF_LINK)
201 len += ETHERIP_ALIGN;
202#endif
203 M_PREPEND(m, len, M_DONTWAIT);
204 if (m != NULL && m->m_len < len)
205 m = m_pullup(m, len);
206 if (m == NULL) {
207 printf("ENOBUFS in in_gif_output %d\n", __LINE__);
208 return ENOBUFS;
209 }
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"));
215 m->m_data += len;
216 m->m_len -= ETHERIP_ALIGN;
217 }
218#endif
219 bcopy(&iphdr, mtod(m, struct ip *), sizeof(struct ip));
220
221 M_SETFIB(m, sc->gif_fibnum);
222
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;
233 }
234#if 0
235 GIF2IFP(sc)->if_mtu = GIF_MTU;
236#endif
237 }
238
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) {
242 m_freem(m);
243 return ENETUNREACH;
244 }
245
246 /* if it constitutes infinite encapsulation, punt. */
247 if (sc->gif_ro.ro_rt->rt_ifp == ifp) {
248 m_freem(m);
249 return ENETUNREACH; /* XXX */
250 }
251#if 0
252 ifp->if_mtu = sc->gif_ro.ro_rt->rt_ifp->if_mtu
253 - sizeof(struct ip);
254#endif
255 }
256
257 error = ip_output(m, NULL, &sc->gif_ro, 0, NULL, NULL);
258
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;
263 }
264
265 return (error);
266}
267
268void
269in_gif_input(struct mbuf *m, int off)
270{
271 struct ifnet *gifp = NULL;
272 struct gif_softc *sc;
273 struct ip *ip;
274 int af;
275 u_int8_t otos;
276 int proto;
277
278 ip = mtod(m, struct ip *);
279 proto = ip->ip_p;
280
281 sc = (struct gif_softc *)encap_getarg(m);
282 if (sc == NULL) {
283 m_freem(m);
284 IPSTAT_INC(ips_nogif);
285 return;
286 }
287
288 gifp = GIF2IFP(sc);
289 if (gifp == NULL || (gifp->if_flags & IFF_UP) == 0) {
290 m_freem(m);
291 IPSTAT_INC(ips_nogif);
292 return;
293 }
294
295 otos = ip->ip_tos;
296 m_adj(m, off);
297
298 switch (proto) {
299#ifdef INET
300 case IPPROTO_IPV4:
301 {
302 struct ip *ip;
303 af = AF_INET;
304 if (m->m_len < sizeof(*ip)) {
305 m = m_pullup(m, sizeof(*ip));
306 if (!m)
307 return;
308 }
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) {
313 m_freem(m);
314 return;
315 }
316 break;
317 }
318#endif
319#ifdef INET6
320 case IPPROTO_IPV6:
321 {
322 struct ip6_hdr *ip6;
323 u_int8_t itos, oitos;
324
325 af = AF_INET6;
326 if (m->m_len < sizeof(*ip6)) {
327 m = m_pullup(m, sizeof(*ip6));
328 if (!m)
329 return;
330 }
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) {
336 m_freem(m);
337 return;
338 }
339 if (itos != oitos) {
340 ip6->ip6_flow &= ~htonl(0xff << 20);
341 ip6->ip6_flow |= htonl((u_int32_t)itos << 20);
342 }
343 break;
344 }
345#endif /* INET6 */
346 case IPPROTO_ETHERIP:
347 af = AF_LINK;
348 break;
349
350 default:
351 IPSTAT_INC(ips_nogif);
352 m_freem(m);
353 return;
354 }
355 gif_input(m, af, gifp);
356 return;
357}
358
359/*
360 * validate outer address.
361 */
362static int
363gif_validate4(const struct ip *ip, struct gif_softc *sc, struct ifnet *ifp)
364{
365 struct sockaddr_in *src, *dst;
366 struct in_ifaddr *ia4;
367
368 src = (struct sockaddr_in *)sc->gif_psrc;
369 dst = (struct sockaddr_in *)sc->gif_pdst;
370
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)
374 return 0;
375
376 /* martian filters on outer source - NOT done in ip_input! */
377 if (IN_MULTICAST(ntohl(ip->ip_src.s_addr)))
378 return 0;
379 switch ((ntohl(ip->ip_src.s_addr) & 0xff000000) >> 24) {
380 case 0: case 127: case 255:
381 return 0;
382 }
383
384 /* reject packets with broadcast on source */
385 /* XXXRW: should use hash lists? */
386 IN_IFADDR_RLOCK();
387 TAILQ_FOREACH(ia4, &V_in_ifaddrhead, ia_link) {
388 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0)
389 continue;
390 if (ip->ip_src.s_addr == ia4->ia_broadaddr.sin_addr.s_addr) {
391 IN_IFADDR_RUNLOCK();
392 return 0;
393 }
394 }
395 IN_IFADDR_RUNLOCK();
396
397 /* ingress filters on outer source */
398 if ((GIF2IFP(sc)->if_flags & IFF_LINK2) == 0 && ifp) {
399 struct sockaddr_in sin;
400 struct rtentry *rt;
401
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) {
410#if 0
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));
414#endif
415 if (rt)
416 RTFREE_LOCKED(rt);
417 return 0;
418 }
419 RTFREE_LOCKED(rt);
420 }
421
422 return 32 * 2;
423}
424
425/*
426 * we know that we are in IFF_UP, outer address available, and outer family
427 * matched the physical addr family. see gif_encapcheck().
428 */
429int
430gif_encapcheck4(const struct mbuf *m, int off, int proto, void *arg)
431{
432 struct ip ip;
433 struct gif_softc *sc;
434 struct ifnet *ifp;
435
436 /* sanity check done in caller */
437 sc = (struct gif_softc *)arg;
438
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;
442
443 return gif_validate4(&ip, sc, ifp);
444}
445
446int
447in_gif_attach(struct gif_softc *sc)
448{
449 sc->encap_cookie4 = encap_attach_func(AF_INET, -1, gif_encapcheck,
450 &in_gif_protosw, sc);
451 if (sc->encap_cookie4 == NULL)
452 return EEXIST;
453 return 0;
454}
455
456int
457in_gif_detach(struct gif_softc *sc)
458{
459 int error;
460
461 error = encap_detach(sc->encap_cookie4);
462 if (error == 0)
463 sc->encap_cookie4 = NULL;
464 return error;
465}
2
3/*-
4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
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.
18 *
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
29 * SUCH DAMAGE.
30 */
31
32#include <sys/cdefs.h>
33__FBSDID("$FreeBSD: head/sys/netinet/in_gif.c 196019 2009-08-01 19:26:27Z rwatson $");
34
35#include "opt_mrouting.h"
36#include "opt_inet.h"
37#include "opt_inet6.h"
38
39#include <sys/param.h>
40#include <sys/systm.h>
41#include <sys/socket.h>
42#include <sys/sockio.h>
43#include <sys/mbuf.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>
49
50#include <net/if.h>
51#include <net/route.h>
52#include <net/vnet.h>
53
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>
62
63#ifdef INET6
64#include <netinet/ip6.h>
65#endif
66
67#ifdef MROUTING
68#include <netinet/ip_mroute.h>
69#endif /* MROUTING */
70
71#include <net/if_gif.h>
72
73static int gif_validate4(const struct ip *, struct gif_softc *,
74 struct ifnet *);
75
76extern struct domain inetdomain;
77struct protosw in_gif_protosw = {
78 .pr_type = SOCK_RAW,
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
86};
87
88SYSCTL_VNET_INT(_net_inet_ip, IPCTL_GIF_TTL, gifttl, CTLFLAG_RW,
89 &VNET_NAME(ip_gif_ttl), 0, "");
90
91int
92in_gif_output(struct ifnet *ifp, int family, struct mbuf *m)
93{
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;
101 u_int8_t tos;
102
103 GIF_LOCK_ASSERT(sc);
104
105 if (sin_src == NULL || sin_dst == NULL ||
106 sin_src->sin_family != AF_INET ||
107 sin_dst->sin_family != AF_INET) {
108 m_freem(m);
109 return EAFNOSUPPORT;
110 }
111
112 switch (family) {
113#ifdef INET
114 case AF_INET:
115 {
116 struct ip *ip;
117
118 proto = IPPROTO_IPV4;
119 if (m->m_len < sizeof(*ip)) {
120 m = m_pullup(m, sizeof(*ip));
121 if (!m)
122 return ENOBUFS;
123 }
124 ip = mtod(m, struct ip *);
125 tos = ip->ip_tos;
126 break;
127 }
128#endif /* INET */
129#ifdef INET6
130 case AF_INET6:
131 {
132 struct ip6_hdr *ip6;
133 proto = IPPROTO_IPV6;
134 if (m->m_len < sizeof(*ip6)) {
135 m = m_pullup(m, sizeof(*ip6));
136 if (!m)
137 return ENOBUFS;
138 }
139 ip6 = mtod(m, struct ip6_hdr *);
140 tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
141 break;
142 }
143#endif /* INET6 */
144 case AF_LINK:
145 proto = IPPROTO_ETHERIP;
146
147 /*
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.
152 */
153 if ((sc->gif_options & GIF_SEND_REVETHIP)) {
154 eiphdr.eip_ver = 0;
155 eiphdr.eip_resvl = ETHERIP_VERSION;
156 eiphdr.eip_resvh = 0;
157 } else {
158 eiphdr.eip_ver = ETHERIP_VERSION;
159 eiphdr.eip_resvl = 0;
160 eiphdr.eip_resvh = 0;
161 }
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));
166 if (m == NULL)
167 return ENOBUFS;
168 bcopy(&eiphdr, mtod(m, struct etherip_header *),
169 sizeof(struct etherip_header));
170 break;
171
172 default:
173#ifdef DEBUG
174 printf("in_gif_output: warning: unknown family %d passed\n",
175 family);
176#endif
177 m_freem(m);
178 return EAFNOSUPPORT;
179 }
180
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;
186 else {
187 m_freem(m);
188 return ENETUNREACH;
189 }
190 iphdr.ip_p = proto;
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);
196
197 /* prepend new IP header */
198 len = sizeof(struct ip);
199#ifndef __NO_STRICT_ALIGNMENT
200 if (family == AF_LINK)
201 len += ETHERIP_ALIGN;
202#endif
203 M_PREPEND(m, len, M_DONTWAIT);
204 if (m != NULL && m->m_len < len)
205 m = m_pullup(m, len);
206 if (m == NULL) {
207 printf("ENOBUFS in in_gif_output %d\n", __LINE__);
208 return ENOBUFS;
209 }
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"));
215 m->m_data += len;
216 m->m_len -= ETHERIP_ALIGN;
217 }
218#endif
219 bcopy(&iphdr, mtod(m, struct ip *), sizeof(struct ip));
220
221 M_SETFIB(m, sc->gif_fibnum);
222
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;
233 }
234#if 0
235 GIF2IFP(sc)->if_mtu = GIF_MTU;
236#endif
237 }
238
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) {
242 m_freem(m);
243 return ENETUNREACH;
244 }
245
246 /* if it constitutes infinite encapsulation, punt. */
247 if (sc->gif_ro.ro_rt->rt_ifp == ifp) {
248 m_freem(m);
249 return ENETUNREACH; /* XXX */
250 }
251#if 0
252 ifp->if_mtu = sc->gif_ro.ro_rt->rt_ifp->if_mtu
253 - sizeof(struct ip);
254#endif
255 }
256
257 error = ip_output(m, NULL, &sc->gif_ro, 0, NULL, NULL);
258
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;
263 }
264
265 return (error);
266}
267
268void
269in_gif_input(struct mbuf *m, int off)
270{
271 struct ifnet *gifp = NULL;
272 struct gif_softc *sc;
273 struct ip *ip;
274 int af;
275 u_int8_t otos;
276 int proto;
277
278 ip = mtod(m, struct ip *);
279 proto = ip->ip_p;
280
281 sc = (struct gif_softc *)encap_getarg(m);
282 if (sc == NULL) {
283 m_freem(m);
284 IPSTAT_INC(ips_nogif);
285 return;
286 }
287
288 gifp = GIF2IFP(sc);
289 if (gifp == NULL || (gifp->if_flags & IFF_UP) == 0) {
290 m_freem(m);
291 IPSTAT_INC(ips_nogif);
292 return;
293 }
294
295 otos = ip->ip_tos;
296 m_adj(m, off);
297
298 switch (proto) {
299#ifdef INET
300 case IPPROTO_IPV4:
301 {
302 struct ip *ip;
303 af = AF_INET;
304 if (m->m_len < sizeof(*ip)) {
305 m = m_pullup(m, sizeof(*ip));
306 if (!m)
307 return;
308 }
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) {
313 m_freem(m);
314 return;
315 }
316 break;
317 }
318#endif
319#ifdef INET6
320 case IPPROTO_IPV6:
321 {
322 struct ip6_hdr *ip6;
323 u_int8_t itos, oitos;
324
325 af = AF_INET6;
326 if (m->m_len < sizeof(*ip6)) {
327 m = m_pullup(m, sizeof(*ip6));
328 if (!m)
329 return;
330 }
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) {
336 m_freem(m);
337 return;
338 }
339 if (itos != oitos) {
340 ip6->ip6_flow &= ~htonl(0xff << 20);
341 ip6->ip6_flow |= htonl((u_int32_t)itos << 20);
342 }
343 break;
344 }
345#endif /* INET6 */
346 case IPPROTO_ETHERIP:
347 af = AF_LINK;
348 break;
349
350 default:
351 IPSTAT_INC(ips_nogif);
352 m_freem(m);
353 return;
354 }
355 gif_input(m, af, gifp);
356 return;
357}
358
359/*
360 * validate outer address.
361 */
362static int
363gif_validate4(const struct ip *ip, struct gif_softc *sc, struct ifnet *ifp)
364{
365 struct sockaddr_in *src, *dst;
366 struct in_ifaddr *ia4;
367
368 src = (struct sockaddr_in *)sc->gif_psrc;
369 dst = (struct sockaddr_in *)sc->gif_pdst;
370
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)
374 return 0;
375
376 /* martian filters on outer source - NOT done in ip_input! */
377 if (IN_MULTICAST(ntohl(ip->ip_src.s_addr)))
378 return 0;
379 switch ((ntohl(ip->ip_src.s_addr) & 0xff000000) >> 24) {
380 case 0: case 127: case 255:
381 return 0;
382 }
383
384 /* reject packets with broadcast on source */
385 /* XXXRW: should use hash lists? */
386 IN_IFADDR_RLOCK();
387 TAILQ_FOREACH(ia4, &V_in_ifaddrhead, ia_link) {
388 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0)
389 continue;
390 if (ip->ip_src.s_addr == ia4->ia_broadaddr.sin_addr.s_addr) {
391 IN_IFADDR_RUNLOCK();
392 return 0;
393 }
394 }
395 IN_IFADDR_RUNLOCK();
396
397 /* ingress filters on outer source */
398 if ((GIF2IFP(sc)->if_flags & IFF_LINK2) == 0 && ifp) {
399 struct sockaddr_in sin;
400 struct rtentry *rt;
401
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) {
410#if 0
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));
414#endif
415 if (rt)
416 RTFREE_LOCKED(rt);
417 return 0;
418 }
419 RTFREE_LOCKED(rt);
420 }
421
422 return 32 * 2;
423}
424
425/*
426 * we know that we are in IFF_UP, outer address available, and outer family
427 * matched the physical addr family. see gif_encapcheck().
428 */
429int
430gif_encapcheck4(const struct mbuf *m, int off, int proto, void *arg)
431{
432 struct ip ip;
433 struct gif_softc *sc;
434 struct ifnet *ifp;
435
436 /* sanity check done in caller */
437 sc = (struct gif_softc *)arg;
438
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;
442
443 return gif_validate4(&ip, sc, ifp);
444}
445
446int
447in_gif_attach(struct gif_softc *sc)
448{
449 sc->encap_cookie4 = encap_attach_func(AF_INET, -1, gif_encapcheck,
450 &in_gif_protosw, sc);
451 if (sc->encap_cookie4 == NULL)
452 return EEXIST;
453 return 0;
454}
455
456int
457in_gif_detach(struct gif_softc *sc)
458{
459 int error;
460
461 error = encap_detach(sc->encap_cookie4);
462 if (error == 0)
463 sc->encap_cookie4 = NULL;
464 return error;
465}