1 /* $NetBSD: if_stf.c,v 1.109 2022/09/03 02:47:59 thorpej Exp $ */
2 /* $KAME: if_stf.c,v 1.62 2001/06/07 22:32:16 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 RFC3056.
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 * stf interface does not have, and will not need, a link-local address.
64 * It seems to have no real benefit and does not help the above symptoms much.
65 * Even if we assign link-locals to interface, we cannot really
66 * use link-local unicast/multicast on top of 6to4 cloud (since there's no
67 * encapsulation defined for link-local address), and the above analysis does
68 * not change. RFC3056 does not mandate the assignment of link-local address
69 * either.
70 *
71 * 6to4 interface has security issues. Refer to
72 * http://playground.iijlab.net/i-d/draft-itojun-ipv6-transition-abuse-00.txt
73 * for details. The code tries to filter out some of malicious packets.
74 * Note that there is no way to be 100% secure.
75 */
76
77 #include <sys/cdefs.h>
78 __KERNEL_RCSID(0, "$NetBSD: if_stf.c,v 1.109 2022/09/03 02:47:59 thorpej Exp $");
79
80 #ifdef _KERNEL_OPT
81 #include "opt_inet.h"
82 #include "stf.h"
83 #endif
84
85 #ifndef INET6
86 #error "pseudo-device stf requires options INET6"
87 #endif
88
89 #include <sys/param.h>
90 #include <sys/systm.h>
91 #include <sys/socket.h>
92 #include <sys/sockio.h>
93 #include <sys/mbuf.h>
94 #include <sys/errno.h>
95 #include <sys/ioctl.h>
96 #include <sys/proc.h>
97 #include <sys/queue.h>
98 #include <sys/syslog.h>
99 #include <sys/device.h>
100 #include <sys/module.h>
101
102 #include <sys/cpu.h>
103
104 #include <net/if.h>
105 #include <net/route.h>
106 #include <net/if_types.h>
107 #include <net/if_stf.h>
108
109 #include <netinet/in.h>
110 #include <netinet/in_systm.h>
111 #include <netinet/ip.h>
112 #include <netinet/ip_var.h>
113 #include <netinet/in_var.h>
114
115 #include <netinet/ip6.h>
116 #include <netinet6/ip6_var.h>
117 #include <netinet6/in6_var.h>
118 #include <netinet/ip_ecn.h>
119
120 #include <netinet/ip_encap.h>
121
122 #include <net/bpf.h>
123
124 #include "ioconf.h"
125
126 #define IN6_IS_ADDR_6TO4(x) (ntohs((x)->s6_addr16[0]) == 0x2002)
127 #define GET_V4(x) ((const struct in_addr *)(&(x)->s6_addr16[1]))
128
129 struct stf_softc {
130 struct ifnet sc_if; /* common area */
131 struct route sc_ro;
132 const struct encaptab *encap_cookie;
133 LIST_ENTRY(stf_softc) sc_list;
134 };
135
136 static LIST_HEAD(, stf_softc) stf_softc_list;
137
138 static int stf_clone_create(struct if_clone *, int);
139 static int stf_clone_destroy(struct ifnet *);
140
141 struct if_clone stf_cloner =
142 IF_CLONE_INITIALIZER("stf", stf_clone_create, stf_clone_destroy);
143
144 static int ip_stf_ttl = STF_TTL;
145
146 extern struct domain inetdomain;
147
148 static const struct encapsw in_stf_encapsw =
149 {
150 .encapsw4 = {
151 .pr_input = in_stf_input,
152 .pr_ctlinput = NULL,
153 }
154 };
155
156 static int stf_encapcheck(struct mbuf *, int, int, void *);
157 static struct in6_ifaddr *stf_getsrcifa6(struct ifnet *);
158 static int stf_output(struct ifnet *, struct mbuf *, const struct sockaddr *,
159 const struct rtentry *);
160 static int isrfc1918addr(const struct in_addr *);
161 static int stf_checkaddr4(struct stf_softc *, const struct in_addr *,
162 struct ifnet *);
163 static int stf_checkaddr6(struct stf_softc *, const struct in6_addr *,
164 struct ifnet *);
165 static void stf_rtrequest(int, struct rtentry *, const struct rt_addrinfo *);
166 static int stf_ioctl(struct ifnet *, u_long, void *);
167
168 /* ARGSUSED */
169 void
stfattach(int count)170 stfattach(int count)
171 {
172
173 /*
174 * Nothing to do here, initialization is handled by the
175 * module initialization code in stfinit() below).
176 */
177 }
178
179 static void
stfinit(void)180 stfinit(void)
181 {
182
183 LIST_INIT(&stf_softc_list);
184 if_clone_attach(&stf_cloner);
185 }
186
187 static int
stfdetach(void)188 stfdetach(void)
189 {
190 int error = 0;
191
192 if (!LIST_EMPTY(&stf_softc_list))
193 error = EBUSY;
194
195 if (error == 0)
196 if_clone_detach(&stf_cloner);
197
198 return error;
199 }
200
201 static int
stf_clone_create(struct if_clone * ifc,int unit)202 stf_clone_create(struct if_clone *ifc, int unit)
203 {
204 struct stf_softc *sc;
205 int error;
206
207 sc = malloc(sizeof(struct stf_softc), M_DEVBUF, M_WAIT|M_ZERO);
208 if_initname(&sc->sc_if, ifc->ifc_name, unit);
209
210 error = encap_lock_enter();
211 if (error) {
212 free(sc, M_DEVBUF);
213 return error;
214 }
215
216 if (LIST_FIRST(&stf_softc_list) != NULL) {
217 /* Only one stf interface is allowed. */
218 encap_lock_exit();
219 free(sc, M_DEVBUF);
220 return EEXIST;
221 }
222
223 sc->encap_cookie = encap_attach_func(AF_INET, IPPROTO_IPV6,
224 stf_encapcheck, &in_stf_encapsw, sc);
225 encap_lock_exit();
226 if (sc->encap_cookie == NULL) {
227 printf("%s: unable to attach encap\n", if_name(&sc->sc_if));
228 free(sc, M_DEVBUF);
229 return EIO; /* XXX */
230 }
231
232 sc->sc_if.if_mtu = STF_MTU;
233 sc->sc_if.if_flags = 0;
234 sc->sc_if.if_ioctl = stf_ioctl;
235 sc->sc_if.if_output = stf_output;
236 sc->sc_if.if_type = IFT_STF;
237 sc->sc_if.if_dlt = DLT_NULL;
238 if_attach(&sc->sc_if);
239 if_alloc_sadl(&sc->sc_if);
240 bpf_attach(&sc->sc_if, DLT_NULL, sizeof(u_int));
241 LIST_INSERT_HEAD(&stf_softc_list, sc, sc_list);
242 return 0;
243 }
244
245 static int
stf_clone_destroy(struct ifnet * ifp)246 stf_clone_destroy(struct ifnet *ifp)
247 {
248 struct stf_softc *sc = (void *) ifp;
249
250 encap_lock_enter();
251 LIST_REMOVE(sc, sc_list);
252 encap_detach(sc->encap_cookie);
253 encap_lock_exit();
254 bpf_detach(ifp);
255 if_detach(ifp);
256 rtcache_free(&sc->sc_ro);
257 free(sc, M_DEVBUF);
258
259 return 0;
260 }
261
262 static int
stf_encapcheck(struct mbuf * m,int off,int proto,void * arg)263 stf_encapcheck(struct mbuf *m, int off, int proto, void *arg)
264 {
265 struct ip ip;
266 struct in6_ifaddr *ia6;
267 struct stf_softc *sc;
268 struct in_addr a, b;
269
270 sc = (struct stf_softc *)arg;
271 if (sc == NULL)
272 return 0;
273
274 if ((sc->sc_if.if_flags & IFF_UP) == 0)
275 return 0;
276
277 /* IFF_LINK0 means "no decapsulation" */
278 if ((sc->sc_if.if_flags & IFF_LINK0) != 0)
279 return 0;
280
281 if (proto != IPPROTO_IPV6)
282 return 0;
283
284 m_copydata(m, 0, sizeof(ip), (void *)&ip);
285
286 if (ip.ip_v != 4)
287 return 0;
288
289 ia6 = stf_getsrcifa6(&sc->sc_if);
290 if (ia6 == NULL)
291 return 0;
292
293 /*
294 * check if IPv4 dst matches the IPv4 address derived from the
295 * local 6to4 address.
296 * success on: dst = 10.1.1.1, ia6->ia_addr = 2002:0a01:0101:...
297 */
298 if (memcmp(GET_V4(&ia6->ia_addr.sin6_addr), &ip.ip_dst,
299 sizeof(ip.ip_dst)) != 0)
300 return 0;
301
302 /*
303 * check if IPv4 src matches the IPv4 address derived from the
304 * local 6to4 address masked by prefixmask.
305 * success on: src = 10.1.1.1, ia6->ia_addr = 2002:0a00:.../24
306 * fail on: src = 10.1.1.1, ia6->ia_addr = 2002:0b00:.../24
307 */
308 memset(&a, 0, sizeof(a));
309 a.s_addr = GET_V4(&ia6->ia_addr.sin6_addr)->s_addr;
310 a.s_addr &= GET_V4(&ia6->ia_prefixmask.sin6_addr)->s_addr;
311 b = ip.ip_src;
312 b.s_addr &= GET_V4(&ia6->ia_prefixmask.sin6_addr)->s_addr;
313 if (a.s_addr != b.s_addr)
314 return 0;
315
316 /* stf interface makes single side match only */
317 return 32;
318 }
319
320 static struct in6_ifaddr *
stf_getsrcifa6(struct ifnet * ifp)321 stf_getsrcifa6(struct ifnet *ifp)
322 {
323 struct ifaddr *ifa;
324 struct in_ifaddr *ia4;
325 struct sockaddr_in6 *sin6;
326 struct in_addr in;
327 int s;
328
329 s = pserialize_read_enter();
330 IFADDR_READER_FOREACH(ifa, ifp) {
331 if (ifa->ifa_addr->sa_family != AF_INET6)
332 continue;
333 sin6 = (struct sockaddr_in6 *)ifa->ifa_addr;
334 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr))
335 continue;
336
337 memcpy(&in, GET_V4(&sin6->sin6_addr), sizeof(in));
338 ia4 = in_get_ia(in);
339 if (ia4 == NULL)
340 continue;
341
342 pserialize_read_exit(s);
343 /* TODO NOMPSAFE */
344 return (struct in6_ifaddr *)ifa;
345 }
346 pserialize_read_exit(s);
347
348 return NULL;
349 }
350
351 static int
stf_output(struct ifnet * ifp,struct mbuf * m,const struct sockaddr * dst,const struct rtentry * rt0)352 stf_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
353 const struct rtentry *rt0)
354 {
355 struct rtentry *rt;
356 struct stf_softc *sc;
357 const struct sockaddr_in6 *dst6;
358 const struct in_addr *in4;
359 uint8_t tos;
360 struct ip *ip;
361 struct ip6_hdr *ip6;
362 struct in6_ifaddr *ia6;
363 union {
364 struct sockaddr dst;
365 struct sockaddr_in dst4;
366 } u;
367
368 sc = (struct stf_softc*)ifp;
369 dst6 = (const struct sockaddr_in6 *)dst;
370
371 /* just in case */
372 if ((ifp->if_flags & IFF_UP) == 0) {
373 m_freem(m);
374 return ENETDOWN;
375 }
376
377 /*
378 * If we don't have an ip4 address that match my inner ip6 address,
379 * we shouldn't generate output. Without this check, we'll end up
380 * using wrong IPv4 source.
381 */
382 ia6 = stf_getsrcifa6(ifp);
383 if (ia6 == NULL) {
384 m_freem(m);
385 if_statinc(ifp, if_oerrors);
386 return ENETDOWN;
387 }
388
389 if (m->m_len < sizeof(*ip6)) {
390 m = m_pullup(m, sizeof(*ip6));
391 if (m == NULL) {
392 if_statinc(ifp, if_oerrors);
393 return ENOBUFS;
394 }
395 }
396 ip6 = mtod(m, struct ip6_hdr *);
397 tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
398
399 /*
400 * Pickup the right outer dst addr from the list of candidates.
401 * ip6_dst has priority as it may be able to give us shorter IPv4 hops.
402 */
403 if (IN6_IS_ADDR_6TO4(&ip6->ip6_dst))
404 in4 = GET_V4(&ip6->ip6_dst);
405 else if (IN6_IS_ADDR_6TO4(&dst6->sin6_addr))
406 in4 = GET_V4(&dst6->sin6_addr);
407 else {
408 m_freem(m);
409 if_statinc(ifp, if_oerrors);
410 return ENETUNREACH;
411 }
412
413 bpf_mtap_af(ifp, AF_INET6, m, BPF_D_OUT);
414
415 M_PREPEND(m, sizeof(struct ip), M_DONTWAIT);
416 if (m && m->m_len < sizeof(struct ip))
417 m = m_pullup(m, sizeof(struct ip));
418 if (m == NULL) {
419 if_statinc(ifp, if_oerrors);
420 return ENOBUFS;
421 }
422 ip = mtod(m, struct ip *);
423
424 memset(ip, 0, sizeof(*ip));
425
426 bcopy(GET_V4(&((struct sockaddr_in6 *)&ia6->ia_addr)->sin6_addr),
427 &ip->ip_src, sizeof(ip->ip_src));
428 memcpy(&ip->ip_dst, in4, sizeof(ip->ip_dst));
429 ip->ip_p = IPPROTO_IPV6;
430 ip->ip_ttl = ip_stf_ttl;
431 ip->ip_len = htons(m->m_pkthdr.len);
432 if (ifp->if_flags & IFF_LINK1)
433 ip_ecn_ingress(ECN_ALLOWED, &ip->ip_tos, &tos);
434 else
435 ip_ecn_ingress(ECN_NOCARE, &ip->ip_tos, &tos);
436
437 sockaddr_in_init(&u.dst4, &ip->ip_dst, 0);
438 if ((rt = rtcache_lookup(&sc->sc_ro, &u.dst)) == NULL) {
439 m_freem(m);
440 if_statinc(ifp, if_oerrors);
441 return ENETUNREACH;
442 }
443
444 /* If the route constitutes infinite encapsulation, punt. */
445 if (rt->rt_ifp == ifp) {
446 rtcache_unref(rt, &sc->sc_ro);
447 rtcache_free(&sc->sc_ro);
448 m_freem(m);
449 if_statinc(ifp, if_oerrors);
450 return ENETUNREACH;
451 }
452 rtcache_unref(rt, &sc->sc_ro);
453
454 if_statadd2(ifp, if_opackets, 1,
455 if_obytes, m->m_pkthdr.len - sizeof(struct ip));
456 return ip_output(m, NULL, &sc->sc_ro, 0, NULL, NULL);
457 }
458
459 static int
isrfc1918addr(const struct in_addr * in)460 isrfc1918addr(const struct in_addr *in)
461 {
462 /*
463 * returns 1 if private address range:
464 * 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16
465 */
466 if ((ntohl(in->s_addr) & 0xff000000) >> 24 == 10 ||
467 (ntohl(in->s_addr) & 0xfff00000) >> 16 == 172 * 256 + 16 ||
468 (ntohl(in->s_addr) & 0xffff0000) >> 16 == 192 * 256 + 168)
469 return 1;
470
471 return 0;
472 }
473
474 static int
stf_checkaddr4(struct stf_softc * sc,const struct in_addr * in,struct ifnet * inifp)475 stf_checkaddr4(struct stf_softc *sc, const struct in_addr *in,
476 struct ifnet *inifp /*incoming interface*/)
477 {
478 struct in_ifaddr *ia4;
479
480 /*
481 * reject packets with the following address:
482 * 224.0.0.0/4 0.0.0.0/8 127.0.0.0/8 255.0.0.0/8
483 */
484 if (IN_MULTICAST(in->s_addr))
485 return -1;
486 switch ((ntohl(in->s_addr) & 0xff000000) >> 24) {
487 case 0: case 127: case 255:
488 return -1;
489 }
490
491 /*
492 * reject packets with private address range.
493 * (requirement from RFC3056 section 2 1st paragraph)
494 */
495 if (isrfc1918addr(in))
496 return -1;
497
498 /*
499 * reject packet with IPv4 link-local (169.254.0.0/16),
500 * as suggested in draft-savola-v6ops-6to4-security-00.txt
501 */
502 if (((ntohl(in->s_addr) & 0xff000000) >> 24) == 169 &&
503 ((ntohl(in->s_addr) & 0x00ff0000) >> 16) == 254)
504 return -1;
505
506 /*
507 * reject packets with broadcast
508 */
509 IN_ADDRLIST_READER_FOREACH(ia4) {
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 memset(&sin, 0, sizeof(sin));
524 sin.sin_family = AF_INET;
525 sin.sin_len = sizeof(struct sockaddr_in);
526 sin.sin_addr = *in;
527 rt = rtalloc1((struct sockaddr *)&sin, 0);
528 if (!rt || rt->rt_ifp != inifp) {
529 #if 0
530 log(LOG_WARNING, "%s: packet from 0x%x dropped "
531 "due to ingress filter\n", if_name(&sc->sc_if),
532 (uint32_t)ntohl(sin.sin_addr.s_addr));
533 #endif
534 if (rt)
535 rt_unref(rt);
536 return -1;
537 }
538 rt_unref(rt);
539 }
540
541 return 0;
542 }
543
544 static int
stf_checkaddr6(struct stf_softc * sc,const struct in6_addr * in6,struct ifnet * inifp)545 stf_checkaddr6(struct stf_softc *sc, const struct in6_addr *in6,
546 struct ifnet *inifp /*incoming interface*/)
547 {
548
549 /*
550 * check 6to4 addresses
551 */
552 if (IN6_IS_ADDR_6TO4(in6))
553 return stf_checkaddr4(sc, GET_V4(in6), inifp);
554
555 /*
556 * reject anything that look suspicious. the test is implemented
557 * in ip6_input too, but we check here as well to
558 * (1) reject bad packets earlier, and
559 * (2) to be safe against future ip6_input change.
560 */
561 if (IN6_IS_ADDR_V4COMPAT(in6) || IN6_IS_ADDR_V4MAPPED(in6))
562 return -1;
563
564 /*
565 * reject link-local and site-local unicast
566 * as suggested in draft-savola-v6ops-6to4-security-00.txt
567 */
568 if (IN6_IS_ADDR_LINKLOCAL(in6) || IN6_IS_ADDR_SITELOCAL(in6))
569 return -1;
570
571 /*
572 * reject node-local and link-local multicast
573 * as suggested in draft-savola-v6ops-6to4-security-00.txt
574 */
575 if (IN6_IS_ADDR_MC_NODELOCAL(in6) || IN6_IS_ADDR_MC_LINKLOCAL(in6))
576 return -1;
577
578 return 0;
579 }
580
581 void
in_stf_input(struct mbuf * m,int off,int proto,void * eparg)582 in_stf_input(struct mbuf *m, int off, int proto, void *eparg)
583 {
584 int s;
585 struct stf_softc *sc = eparg;
586 struct ip *ip;
587 struct ip6_hdr *ip6;
588 uint8_t otos, itos;
589 struct ifnet *ifp;
590 size_t pktlen;
591
592 KASSERT(sc != NULL);
593
594 if (proto != IPPROTO_IPV6) {
595 m_freem(m);
596 return;
597 }
598
599 ip = mtod(m, struct ip *);
600
601 if ((sc->sc_if.if_flags & IFF_UP) == 0) {
602 m_freem(m);
603 return;
604 }
605
606 ifp = &sc->sc_if;
607
608 /*
609 * perform sanity check against outer src/dst.
610 * for source, perform ingress filter as well.
611 */
612 if (stf_checkaddr4(sc, &ip->ip_dst, NULL) < 0 ||
613 stf_checkaddr4(sc, &ip->ip_src, m_get_rcvif_NOMPSAFE(m)) < 0) {
614 m_freem(m);
615 return;
616 }
617
618 otos = ip->ip_tos;
619 m_adj(m, off);
620
621 if (m->m_len < sizeof(*ip6)) {
622 m = m_pullup(m, sizeof(*ip6));
623 if (!m)
624 return;
625 }
626 ip6 = mtod(m, struct ip6_hdr *);
627
628 /*
629 * perform sanity check against inner src/dst.
630 * for source, perform ingress filter as well.
631 */
632 if (stf_checkaddr6(sc, &ip6->ip6_dst, NULL) < 0 ||
633 stf_checkaddr6(sc, &ip6->ip6_src, m_get_rcvif_NOMPSAFE(m)) < 0) {
634 m_freem(m);
635 return;
636 }
637
638 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
639 if ((ifp->if_flags & IFF_LINK1) != 0)
640 ip_ecn_egress(ECN_ALLOWED, &otos, &itos);
641 else
642 ip_ecn_egress(ECN_NOCARE, &otos, &itos);
643 ip6->ip6_flow &= ~htonl(0xff << 20);
644 ip6->ip6_flow |= htonl((uint32_t)itos << 20);
645
646 pktlen = m->m_pkthdr.len;
647 m_set_rcvif(m, ifp);
648
649 bpf_mtap_af(ifp, AF_INET6, m, BPF_D_IN);
650
651 /*
652 * Put the packet to the network layer input queue according to the
653 * specified address family.
654 * See net/if_gif.c for possible issues with packet processing
655 * reorder due to extra queueing.
656 */
657
658 s = splnet();
659 if (__predict_true(pktq_enqueue(ip6_pktq, m, 0))) {
660 if_statadd2(ifp, if_ipackets, 1, if_ibytes, pktlen);
661 } else {
662 m_freem(m);
663 }
664 splx(s);
665
666 return;
667 }
668
669 /* ARGSUSED */
670 static void
stf_rtrequest(int cmd,struct rtentry * rt,const struct rt_addrinfo * info)671 stf_rtrequest(int cmd, struct rtentry *rt,
672 const struct rt_addrinfo *info)
673 {
674 if (rt != NULL) {
675 struct stf_softc *sc;
676
677 sc = LIST_FIRST(&stf_softc_list);
678 rt->rt_rmx.rmx_mtu = (sc != NULL) ? sc->sc_if.if_mtu : STF_MTU;
679 }
680 }
681
682 static int
stf_ioctl(struct ifnet * ifp,u_long cmd,void * data)683 stf_ioctl(struct ifnet *ifp, u_long cmd, void *data)
684 {
685 struct ifaddr *ifa;
686 struct ifreq *ifr = data;
687 struct sockaddr_in6 *sin6;
688 int error;
689
690 error = 0;
691 switch (cmd) {
692 case SIOCINITIFADDR:
693 ifa = (struct ifaddr *)data;
694 if (ifa == NULL || ifa->ifa_addr->sa_family != AF_INET6) {
695 error = EAFNOSUPPORT;
696 break;
697 }
698 sin6 = (struct sockaddr_in6 *)ifa->ifa_addr;
699 if (IN6_IS_ADDR_6TO4(&sin6->sin6_addr) &&
700 !isrfc1918addr(GET_V4(&sin6->sin6_addr))) {
701 ifa->ifa_rtrequest = stf_rtrequest;
702 ifp->if_flags |= IFF_UP;
703 } else
704 error = EINVAL;
705 break;
706
707 case SIOCADDMULTI:
708 case SIOCDELMULTI:
709 if (ifr != NULL &&
710 ifreq_getaddr(cmd, ifr)->sa_family == AF_INET6)
711 ;
712 else
713 error = EAFNOSUPPORT;
714 break;
715
716 case SIOCSIFMTU:
717 if (ifr->ifr_mtu < STF_MTU_MIN || ifr->ifr_mtu > STF_MTU_MAX)
718 return EINVAL;
719 else if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET)
720 error = 0;
721 break;
722
723 default:
724 error = ifioctl_common(ifp, cmd, data);
725 break;
726 }
727
728 return error;
729 }
730
731 /*
732 * Module infrastructure
733 */
734 #include "if_module.h"
735
736 IF_MODULE(MODULE_CLASS_DRIVER, stf, NULL)
737