if_stf.c revision 1.4.2.2 1 /* $NetBSD: if_stf.c,v 1.4.2.2 2001/05/01 11:55:37 he Exp $ */
2 /* $KAME: if_stf.c,v 1.39 2000/06/07 23:35:18 itojun Exp $ */
3
4 /*
5 * Copyright (C) 2000 WIDE Project.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
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.
19 *
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
30 * SUCH DAMAGE.
31 */
32
33 /*
34 * 6to4 interface, based on draft-ietf-ngtrans-6to4-06.txt.
35 *
36 * 6to4 interface is NOT capable of link-layer (I mean, IPv4) multicasting.
37 * There is no address mapping defined from IPv6 multicast address to IPv4
38 * address. Therefore, we do not have IFF_MULTICAST on the interface.
39 *
40 * Due to the lack of address mapping for link-local addresses, we cannot
41 * throw packets toward link-local addresses (fe80::x). Also, we cannot throw
42 * packets to link-local multicast addresses (ff02::x).
43 *
44 * Here are interesting symptoms due to the lack of link-local address:
45 *
46 * Unicast routing exchange:
47 * - RIPng: Impossible. Uses link-local multicast packet toward ff02::9,
48 * and link-local addresses as nexthop.
49 * - OSPFv6: Impossible. OSPFv6 assumes that there's link-local address
50 * assigned to the link, and makes use of them. Also, HELLO packets use
51 * link-local multicast addresses (ff02::5 and ff02::6).
52 * - BGP4+: Maybe. You can only use global address as nexthop, and global
53 * address as TCP endpoint address.
54 *
55 * Multicast routing protocols:
56 * - PIM: Hello packet cannot be used to discover adjacent PIM routers.
57 * Adjacent PIM routers must be configured manually (is it really spec-wise
58 * correct thing to do?).
59 *
60 * ICMPv6:
61 * - Redirects cannot be used due to the lack of link-local address.
62 *
63 * Starting from 04 draft, the specification suggests how to construct
64 * link-local address for 6to4 interface.
65 * However, it seems to have no real use and does not help the above symptom
66 * much. Even if we assign link-locals to interface, we cannot really
67 * use link-local unicast/multicast on top of 6to4 cloud, and the above
68 * analysis does not change.
69 *
70 * 6to4 interface has security issues. Refer to
71 * http://playground.iijlab.net/i-d/draft-itojun-ipv6-transition-abuse-00.txt
72 * for details. The code tries to filter out some of malicious packets.
73 * Note that there is no way to be 100% secure.
74 */
75
76 #if defined(__FreeBSD__) && __FreeBSD__ >= 3
77 #include "opt_inet.h"
78 #include "opt_inet6.h"
79 #endif
80 #ifdef __NetBSD__
81 #include "opt_inet.h"
82 #endif
83
84 #include <sys/param.h>
85 #include <sys/systm.h>
86 #include <sys/socket.h>
87 #include <sys/sockio.h>
88 #include <sys/mbuf.h>
89 #include <sys/errno.h>
90 #if !(defined(__FreeBSD__) && __FreeBSD__ >= 3)
91 #include <sys/ioctl.h>
92 #endif
93 #include <sys/protosw.h>
94 #ifdef __FreeBSD__
95 #include <sys/kernel.h>
96 #endif
97 #include <sys/queue.h>
98 #include <sys/syslog.h>
99 #include <machine/cpu.h>
100
101 #if defined(__FreeBSD__) && __FreeBSD__ >= 3
102 #include <sys/malloc.h>
103 #endif
104
105 #include <net/if.h>
106 #include <net/route.h>
107 #include <net/netisr.h>
108 #include <net/if_types.h>
109 #include <net/if_stf.h>
110
111 #include <netinet/in.h>
112 #include <netinet/in_systm.h>
113 #include <netinet/ip.h>
114 #include <netinet/ip_var.h>
115 #include <netinet/in_var.h>
116
117 #include <netinet/ip6.h>
118 #include <netinet6/ip6_var.h>
119 #include <netinet6/in6_gif.h>
120 #include <netinet6/in6_var.h>
121 #include <netinet/ip_ecn.h>
122
123 #include <netinet/ip_encap.h>
124
125 #include <machine/stdarg.h>
126
127 #include <net/net_osdep.h>
128
129 #if defined(__FreeBSD__) && __FreeBSD__ >= 4
130 #include "bpf.h"
131 #define NBPFILTER NBPF
132 #else
133 #include "bpfilter.h"
134 #endif
135 #include "stf.h"
136 #include "gif.h" /*XXX*/
137
138 #if NBPFILTER > 0
139 #include <net/bpf.h>
140 #endif
141
142 #if NGIF > 0
143 #include <net/if_gif.h>
144 #endif
145
146 #if NSTF > 0
147 #if NSTF != 1
148 # error only single stf interface allowed
149 #endif
150
151 #define IN6_IS_ADDR_6TO4(x) (ntohs((x)->s6_addr16[0]) == 0x2002)
152 #define GET_V4(x) ((struct in_addr *)(&(x)->s6_addr16[1]))
153
154 struct stf_softc {
155 struct ifnet sc_if; /* common area */
156 union {
157 struct route __sc_ro4;
158 struct route_in6 __sc_ro6; /* just for safety */
159 } __sc_ro46;
160 #define sc_ro __sc_ro46.__sc_ro4
161 const struct encaptab *encap_cookie;
162 };
163
164 static struct stf_softc *stf;
165 static int nstf;
166
167 #if NGIF > 0
168 extern int ip_gif_ttl; /*XXX*/
169 #else
170 static int ip_gif_ttl = 40; /*XXX*/
171 #endif
172
173 extern struct protosw in_stf_protosw;
174
175 #ifdef __FreeBSD__
176 void stfattach __P((void *));
177 #else
178 void stfattach __P((int));
179 #endif
180 static int stf_encapcheck __P((const struct mbuf *, int, int, void *));
181 static struct in6_ifaddr *stf_getsrcifa6 __P((struct ifnet *));
182 static int stf_output __P((struct ifnet *, struct mbuf *, struct sockaddr *,
183 struct rtentry *));
184 static int stf_checkaddr4 __P((struct stf_softc *, struct in_addr *,
185 struct ifnet *));
186 static int stf_checkaddr6 __P((struct stf_softc *, struct in6_addr *,
187 struct ifnet *));
188 #if defined(__bsdi__) && _BSDI_VERSION >= 199802
189 static void stf_rtrequest __P((int, struct rtentry *, struct rt_addrinfo *));
190 #else
191 static void stf_rtrequest __P((int, struct rtentry *, struct sockaddr *));
192 #endif
193 #if defined(__FreeBSD__) && __FreeBSD__ < 3
194 static int stf_ioctl __P((struct ifnet *, int, caddr_t));
195 #else
196 static int stf_ioctl __P((struct ifnet *, u_long, caddr_t));
197 #endif
198
199 void
200 stfattach(dummy)
201 #ifdef __FreeBSD__
202 void *dummy;
203 #else
204 int dummy;
205 #endif
206 {
207 struct stf_softc *sc;
208 int i;
209 const struct encaptab *p;
210
211 #ifdef __NetBSD__
212 nstf = dummy;
213 #else
214 nstf = NSTF;
215 #endif
216 stf = malloc(nstf * sizeof(struct stf_softc), M_DEVBUF, M_WAIT);
217 bzero(stf, nstf * sizeof(struct stf_softc));
218 sc = stf;
219
220 /* XXX just in case... */
221 for (i = 0; i < nstf; i++) {
222 sc = &stf[i];
223 bzero(sc, sizeof(*sc));
224 #if defined(__NetBSD__) || defined(__OpenBSD__)
225 sprintf(sc->sc_if.if_xname, "stf%d", i);
226 #else
227 sc->sc_if.if_name = "stf";
228 sc->sc_if.if_unit = i;
229 #endif
230
231 p = encap_attach_func(AF_INET, IPPROTO_IPV6, stf_encapcheck,
232 &in_stf_protosw, sc);
233 if (p == NULL) {
234 printf("%s: attach failed\n", if_name(&sc->sc_if));
235 continue;
236 }
237 sc->encap_cookie = p;
238
239 sc->sc_if.if_mtu = IPV6_MMTU;
240 sc->sc_if.if_flags = 0;
241 sc->sc_if.if_ioctl = stf_ioctl;
242 sc->sc_if.if_output = stf_output;
243 sc->sc_if.if_type = IFT_STF;
244 #if defined(__FreeBSD__) && __FreeBSD__ >= 4
245 sc->sc_if.if_snd.ifq_maxlen = IFQ_MAXLEN;
246 #endif
247 if_attach(&sc->sc_if);
248 #if NBPFILTER > 0
249 #ifdef HAVE_OLD_BPF
250 bpfattach(&sc->sc_if, DLT_NULL, sizeof(u_int));
251 #else
252 bpfattach(&sc->sc_if.if_bpf, &sc->sc_if, DLT_NULL, sizeof(u_int));
253 #endif
254 #endif
255 }
256 }
257
258 #ifdef __FreeBSD__
259 PSEUDO_SET(stfattach, if_stf);
260 #endif
261
262 static int
263 stf_encapcheck(m, off, proto, arg)
264 const struct mbuf *m;
265 int off;
266 int proto;
267 void *arg;
268 {
269 struct ip ip;
270 struct in6_ifaddr *ia6;
271 struct stf_softc *sc;
272 struct in_addr a, b;
273
274 sc = (struct stf_softc *)arg;
275 if (sc == NULL)
276 return 0;
277
278 if ((sc->sc_if.if_flags & IFF_UP) == 0)
279 return 0;
280
281 if (proto != IPPROTO_IPV6)
282 return 0;
283
284 /* LINTED const cast */
285 m_copydata((struct mbuf *)m, 0, sizeof(ip), (caddr_t)&ip);
286
287 if (ip.ip_v != 4)
288 return 0;
289
290 ia6 = stf_getsrcifa6(&sc->sc_if);
291 if (ia6 == NULL)
292 return 0;
293
294 /*
295 * check if IPv4 dst matches the IPv4 address derived from the
296 * local 6to4 address.
297 * success on: dst = 10.1.1.1, ia6->ia_addr = 2002:0a01:0101:...
298 */
299 if (bcmp(GET_V4(&ia6->ia_addr.sin6_addr), &ip.ip_dst,
300 sizeof(ip.ip_dst)) != 0)
301 return 0;
302
303 /*
304 * check if IPv4 src matches the IPv4 address derived from the
305 * local 6to4 address masked by prefixmask.
306 * success on: src = 10.1.1.1, ia6->ia_addr = 2002:0a00:.../24
307 * fail on: src = 10.1.1.1, ia6->ia_addr = 2002:0b00:.../24
308 */
309 bzero(&a, sizeof(a));
310 a.s_addr = GET_V4(&ia6->ia_addr.sin6_addr)->s_addr;
311 a.s_addr &= GET_V4(&ia6->ia_prefixmask.sin6_addr)->s_addr;
312 b = ip.ip_src;
313 b.s_addr &= GET_V4(&ia6->ia_prefixmask.sin6_addr)->s_addr;
314 if (a.s_addr != b.s_addr)
315 return 0;
316
317 /* stf interface makes single side match only */
318 return 32;
319 }
320
321 static struct in6_ifaddr *
322 stf_getsrcifa6(ifp)
323 struct ifnet *ifp;
324 {
325 struct ifaddr *ia;
326 struct in_ifaddr *ia4;
327 struct sockaddr_in6 *sin6;
328 struct in_addr in;
329
330 #if defined(__bsdi__) || (defined(__FreeBSD__) && __FreeBSD__ < 3)
331 for (ia = ifp->if_addrlist; ia; ia = ia->ifa_next)
332 #else
333 for (ia = ifp->if_addrlist.tqh_first;
334 ia;
335 ia = ia->ifa_list.tqe_next)
336 #endif
337 {
338 if (ia->ifa_addr == NULL)
339 continue;
340 if (ia->ifa_addr->sa_family != AF_INET6)
341 continue;
342 sin6 = (struct sockaddr_in6 *)ia->ifa_addr;
343 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr))
344 continue;
345
346 bcopy(GET_V4(&sin6->sin6_addr), &in, sizeof(in));
347 #ifdef __NetBSD__
348 INADDR_TO_IA(in, ia4);
349 #else
350 #ifdef __OpenBSD__
351 for (ia4 = in_ifaddr.tqh_first;
352 ia4;
353 ia4 = ia4->ia_list.tqe_next)
354 #elif defined(__FreeBSD__) && __FreeBSD__ >= 3
355 for (ia4 = TAILQ_FIRST(&in_ifaddrhead);
356 ia4;
357 ia4 = TAILQ_NEXT(ia4, ia_link))
358 #else
359 for (ia4 = in_ifaddr; ia4 != NULL; ia4 = ia4->ia_next)
360 #endif
361 {
362 if (ia4->ia_addr.sin_addr.s_addr == in.s_addr)
363 break;
364 }
365 #endif
366 if (ia4 == NULL)
367 continue;
368
369 return (struct in6_ifaddr *)ia;
370 }
371
372 return NULL;
373 }
374
375 static int
376 stf_output(ifp, m, dst, rt)
377 struct ifnet *ifp;
378 struct mbuf *m;
379 struct sockaddr *dst;
380 struct rtentry *rt;
381 {
382 struct stf_softc *sc;
383 struct sockaddr_in6 *dst6;
384 struct in_addr *in4;
385 struct sockaddr_in *dst4;
386 u_int8_t tos;
387 struct ip *ip;
388 struct ip6_hdr *ip6;
389 struct in6_ifaddr *ia6;
390
391 sc = (struct stf_softc*)ifp;
392 dst6 = (struct sockaddr_in6 *)dst;
393
394 /* just in case */
395 if ((ifp->if_flags & IFF_UP) == 0) {
396 m_freem(m);
397 return ENETDOWN;
398 }
399
400 /*
401 * If we don't have an ip4 address that match my inner ip6 address,
402 * we shouldn't generate output. Without this check, we'll end up
403 * using wrong IPv4 source.
404 */
405 ia6 = stf_getsrcifa6(ifp);
406 if (ia6 == NULL) {
407 m_freem(m);
408 return ENETDOWN;
409 }
410
411 if (m->m_len < sizeof(*ip6)) {
412 m = m_pullup(m, sizeof(*ip6));
413 if (!m)
414 return ENOBUFS;
415 }
416 ip6 = mtod(m, struct ip6_hdr *);
417 tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
418
419 /*
420 * Pickup the right outer dst addr from the list of candidates.
421 * ip6_dst has priority as it may be able to give us shorter IPv4 hops.
422 */
423 if (IN6_IS_ADDR_6TO4(&ip6->ip6_dst))
424 in4 = GET_V4(&ip6->ip6_dst);
425 else if (IN6_IS_ADDR_6TO4(&dst6->sin6_addr))
426 in4 = GET_V4(&dst6->sin6_addr);
427 else {
428 m_freem(m);
429 return ENETUNREACH;
430 }
431
432 M_PREPEND(m, sizeof(struct ip), M_DONTWAIT);
433 if (m && m->m_len < sizeof(struct ip))
434 m = m_pullup(m, sizeof(struct ip));
435 if (m == NULL)
436 return ENOBUFS;
437 ip = mtod(m, struct ip *);
438
439 bzero(ip, sizeof(*ip));
440
441 bcopy(GET_V4(&((struct sockaddr_in6 *)&ia6->ia_addr)->sin6_addr),
442 &ip->ip_src, sizeof(ip->ip_src));
443 bcopy(in4, &ip->ip_dst, sizeof(ip->ip_dst));
444 ip->ip_p = IPPROTO_IPV6;
445 ip->ip_ttl = ip_gif_ttl; /*XXX*/
446 ip->ip_len = m->m_pkthdr.len; /*host order*/
447 if (ifp->if_flags & IFF_LINK1)
448 ip_ecn_ingress(ECN_ALLOWED, &ip->ip_tos, &tos);
449
450 dst4 = (struct sockaddr_in *)&sc->sc_ro.ro_dst;
451 if (dst4->sin_family != AF_INET ||
452 bcmp(&dst4->sin_addr, &ip->ip_dst, sizeof(ip->ip_dst)) != 0) {
453 /* cache route doesn't match */
454 dst4->sin_family = AF_INET;
455 dst4->sin_len = sizeof(struct sockaddr_in);
456 bcopy(&ip->ip_dst, &dst4->sin_addr, sizeof(dst4->sin_addr));
457 if (sc->sc_ro.ro_rt) {
458 RTFREE(sc->sc_ro.ro_rt);
459 sc->sc_ro.ro_rt = NULL;
460 }
461 }
462
463 if (sc->sc_ro.ro_rt == NULL) {
464 rtalloc(&sc->sc_ro);
465 if (sc->sc_ro.ro_rt == NULL) {
466 m_freem(m);
467 return ENETUNREACH;
468 }
469 }
470
471 #ifndef __OpenBSD__
472 return ip_output(m, NULL, &sc->sc_ro, 0, NULL);
473 #else
474 return ip_output(m, NULL, &sc->sc_ro, 0, NULL, NULL);
475 #endif
476 }
477
478 static int
479 stf_checkaddr4(sc, in, inifp)
480 struct stf_softc *sc;
481 struct in_addr *in;
482 struct ifnet *inifp; /* incoming interface */
483 {
484 struct in_ifaddr *ia4;
485
486 /*
487 * reject packets with the following address:
488 * 224.0.0.0/4 0.0.0.0/8 127.0.0.0/8 255.0.0.0/8
489 */
490 if (IN_MULTICAST(in->s_addr))
491 return -1;
492 switch ((ntohl(in->s_addr) & 0xff000000) >> 24) {
493 case 0: case 127: case 255:
494 return -1;
495 }
496
497 /*
498 * reject packets with broadcast
499 */
500 #if defined(__OpenBSD__) || defined(__NetBSD__)
501 for (ia4 = in_ifaddr.tqh_first; ia4; ia4 = ia4->ia_list.tqe_next)
502 #elif defined(__FreeBSD__) && __FreeBSD__ >= 3
503 for (ia4 = TAILQ_FIRST(&in_ifaddrhead);
504 ia4;
505 ia4 = TAILQ_NEXT(ia4, ia_link))
506 #else
507 for (ia4 = in_ifaddr; ia4 != NULL; ia4 = ia4->ia_next)
508 #endif
509 {
510 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0)
511 continue;
512 if (in->s_addr == ia4->ia_broadaddr.sin_addr.s_addr)
513 return -1;
514 }
515
516 /*
517 * perform ingress filter
518 */
519 if (sc && (sc->sc_if.if_flags & IFF_LINK2) == 0 && inifp) {
520 struct sockaddr_in sin;
521 struct rtentry *rt;
522
523 bzero(&sin, sizeof(sin));
524 sin.sin_family = AF_INET;
525 sin.sin_len = sizeof(struct sockaddr_in);
526 sin.sin_addr = *in;
527 #ifdef __FreeBSD__
528 rt = rtalloc1((struct sockaddr *)&sin, 0, 0UL);
529 #else
530 rt = rtalloc1((struct sockaddr *)&sin, 0);
531 #endif
532 if (!rt || rt->rt_ifp != inifp) {
533 #if 0
534 log(LOG_WARNING, "%s: packet from 0x%x dropped "
535 "due to ingress filter\n", if_name(&sc->sc_if),
536 (u_int32_t)ntohl(sin.sin_addr.s_addr));
537 #endif
538 if (rt)
539 rtfree(rt);
540 return -1;
541 }
542 rtfree(rt);
543 }
544
545 return 0;
546 }
547
548 static int
549 stf_checkaddr6(sc, in6, inifp)
550 struct stf_softc *sc;
551 struct in6_addr *in6;
552 struct ifnet *inifp; /* incoming interface */
553 {
554 /*
555 * check 6to4 addresses
556 */
557 if (IN6_IS_ADDR_6TO4(in6))
558 return stf_checkaddr4(sc, GET_V4(in6), inifp);
559
560 /*
561 * reject anything that look suspicious. the test is implemented
562 * in ip6_input too, but we check here as well to
563 * (1) reject bad packets earlier, and
564 * (2) to be safe against future ip6_input change.
565 */
566 if (IN6_IS_ADDR_V4COMPAT(in6) || IN6_IS_ADDR_V4MAPPED(in6))
567 return -1;
568
569 return 0;
570 }
571
572 void
573 #if __STDC__
574 in_stf_input(struct mbuf *m, ...)
575 #else
576 in_stf_input(m, va_alist)
577 struct mbuf *m;
578 #endif
579 {
580 int off, proto;
581 struct stf_softc *sc;
582 struct ip *ip;
583 struct ip6_hdr *ip6;
584 u_int8_t otos, itos;
585 int s, isr;
586 struct ifqueue *ifq = NULL;
587 struct ifnet *ifp;
588 va_list ap;
589
590 va_start(ap, m);
591 off = va_arg(ap, int);
592 proto = va_arg(ap, int);
593 va_end(ap);
594
595 if (proto != IPPROTO_IPV6) {
596 m_freem(m);
597 return;
598 }
599
600 ip = mtod(m, struct ip *);
601
602 sc = (struct stf_softc *)encap_getarg(m);
603
604 if (sc == NULL || (sc->sc_if.if_flags & IFF_UP) == 0) {
605 m_freem(m);
606 return;
607 }
608
609 ifp = &sc->sc_if;
610
611 /*
612 * perform sanity check against outer src/dst.
613 * for source, perform ingress filter as well.
614 */
615 if (stf_checkaddr4(sc, &ip->ip_dst, NULL) < 0 ||
616 stf_checkaddr4(sc, &ip->ip_src, m->m_pkthdr.rcvif) < 0) {
617 m_freem(m);
618 return;
619 }
620
621 otos = ip->ip_tos;
622 m_adj(m, off);
623
624 if (m->m_len < sizeof(*ip6)) {
625 m = m_pullup(m, sizeof(*ip6));
626 if (!m)
627 return;
628 }
629 ip6 = mtod(m, struct ip6_hdr *);
630
631 /*
632 * perform sanity check against inner src/dst.
633 * for source, perform ingress filter as well.
634 */
635 if (stf_checkaddr6(sc, &ip6->ip6_dst, NULL) < 0 ||
636 stf_checkaddr6(sc, &ip6->ip6_src, m->m_pkthdr.rcvif) < 0) {
637 m_freem(m);
638 return;
639 }
640
641 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
642 if ((ifp->if_flags & IFF_LINK1) != 0)
643 ip_ecn_egress(ECN_ALLOWED, &otos, &itos);
644 ip6->ip6_flow &= ~htonl(0xff << 20);
645 ip6->ip6_flow |= htonl((u_int32_t)itos << 20);
646
647 m->m_pkthdr.rcvif = ifp;
648
649 #if NBPFILTER > 0
650 if (ifp->if_bpf) {
651 /*
652 * We need to prepend the address family as
653 * a four byte field. Cons up a dummy header
654 * to pacify bpf. This is safe because bpf
655 * will only read from the mbuf (i.e., it won't
656 * try to free it or keep a pointer a to it).
657 */
658 struct mbuf m0;
659 u_int af = AF_INET6;
660
661 m0.m_next = m;
662 m0.m_len = 4;
663 m0.m_data = (char *)⁡
664
665 #ifdef HAVE_OLD_BPF
666 bpf_mtap(ifp, &m0);
667 #else
668 bpf_mtap(ifp->if_bpf, &m0);
669 #endif
670 }
671 #endif /*NBPFILTER > 0*/
672
673 /*
674 * Put the packet to the network layer input queue according to the
675 * specified address family.
676 * See net/if_gif.c for possible issues with packet processing
677 * reorder due to extra queueing.
678 */
679 ifq = &ip6intrq;
680 isr = NETISR_IPV6;
681
682 s = splimp();
683 if (IF_QFULL(ifq)) {
684 IF_DROP(ifq); /* update statistics */
685 m_freem(m);
686 splx(s);
687 return;
688 }
689 IF_ENQUEUE(ifq, m);
690 schednetisr(isr);
691 ifp->if_ipackets++;
692 ifp->if_ibytes += m->m_pkthdr.len;
693 splx(s);
694 }
695
696 /* ARGSUSED */
697 static void
698 stf_rtrequest(cmd, rt, sa)
699 int cmd;
700 struct rtentry *rt;
701 #if defined(__bsdi__) && _BSDI_VERSION >= 199802
702 struct rt_addrinfo *sa;
703 #else
704 struct sockaddr *sa;
705 #endif
706 {
707
708 if (rt)
709 rt->rt_rmx.rmx_mtu = IPV6_MMTU;
710 }
711
712 static int
713 stf_ioctl(ifp, cmd, data)
714 struct ifnet *ifp;
715 #if defined(__FreeBSD__) && __FreeBSD__ < 3
716 int cmd;
717 #else
718 u_long cmd;
719 #endif
720 caddr_t data;
721 {
722 struct ifaddr *ifa;
723 struct ifreq *ifr;
724 struct sockaddr_in6 *sin6;
725 int error;
726
727 error = 0;
728 switch (cmd) {
729 case SIOCSIFADDR:
730 ifa = (struct ifaddr *)data;
731 if (ifa == NULL || ifa->ifa_addr->sa_family != AF_INET6) {
732 error = EAFNOSUPPORT;
733 break;
734 }
735 sin6 = (struct sockaddr_in6 *)ifa->ifa_addr;
736 if (IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) {
737 ifa->ifa_rtrequest = stf_rtrequest;
738 ifp->if_flags |= IFF_UP;
739 } else
740 error = EINVAL;
741 break;
742
743 case SIOCADDMULTI:
744 case SIOCDELMULTI:
745 ifr = (struct ifreq *)data;
746 if (ifr && ifr->ifr_addr.sa_family == AF_INET6)
747 ;
748 else
749 error = EAFNOSUPPORT;
750 break;
751
752 default:
753 error = EINVAL;
754 break;
755 }
756
757 return error;
758 }
759
760 #endif /* NSTF > 0 */
761