FreeBSD/Linux Kernel Cross Reference
sys/net/if_stf.c
1 /* $FreeBSD: releng/6.4/sys/net/if_stf.c 166110 2007-01-19 23:01:34Z jhb $ */
2 /* $KAME: if_stf.c,v 1.73 2001/12/03 11:08:30 keiichi 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 "opt_inet.h"
78 #include "opt_inet6.h"
79 #include "opt_mac.h"
80
81 #include <sys/param.h>
82 #include <sys/systm.h>
83 #include <sys/socket.h>
84 #include <sys/sockio.h>
85 #include <sys/mac.h>
86 #include <sys/mbuf.h>
87 #include <sys/errno.h>
88 #include <sys/kernel.h>
89 #include <sys/module.h>
90 #include <sys/protosw.h>
91 #include <sys/queue.h>
92 #include <machine/cpu.h>
93
94 #include <sys/malloc.h>
95
96 #include <net/if.h>
97 #include <net/if_clone.h>
98 #include <net/route.h>
99 #include <net/netisr.h>
100 #include <net/if_types.h>
101 #include <net/if_stf.h>
102
103 #include <netinet/in.h>
104 #include <netinet/in_systm.h>
105 #include <netinet/ip.h>
106 #include <netinet/ip_var.h>
107 #include <netinet/in_var.h>
108
109 #include <netinet/ip6.h>
110 #include <netinet6/ip6_var.h>
111 #include <netinet6/in6_var.h>
112 #include <netinet/ip_ecn.h>
113
114 #include <netinet/ip_encap.h>
115
116 #include <machine/stdarg.h>
117
118 #include <net/net_osdep.h>
119
120 #include <net/bpf.h>
121
122 #define STFNAME "stf"
123 #define STFUNIT 0
124
125 #define IN6_IS_ADDR_6TO4(x) (ntohs((x)->s6_addr16[0]) == 0x2002)
126
127 /*
128 * XXX: Return a pointer with 16-bit aligned. Don't cast it to
129 * struct in_addr *; use bcopy() instead.
130 */
131 #define GET_V4(x) ((caddr_t)(&(x)->s6_addr16[1]))
132
133 struct stf_softc {
134 struct ifnet *sc_ifp;
135 union {
136 struct route __sc_ro4;
137 struct route_in6 __sc_ro6; /* just for safety */
138 } __sc_ro46;
139 #define sc_ro __sc_ro46.__sc_ro4
140 const struct encaptab *encap_cookie;
141 LIST_ENTRY(stf_softc) sc_list; /* all stf's are linked */
142 };
143 #define STF2IFP(sc) ((sc)->sc_ifp)
144
145 /*
146 * All mutable global variables in if_stf.c are protected by stf_mtx.
147 * XXXRW: Note that mutable fields in the softc are not currently locked:
148 * in particular, sc_ro needs to be protected from concurrent entrance
149 * of stf_output().
150 */
151 static struct mtx stf_mtx;
152 static LIST_HEAD(, stf_softc) stf_softc_list;
153
154 static MALLOC_DEFINE(M_STF, STFNAME, "6to4 Tunnel Interface");
155 static const int ip_stf_ttl = 40;
156
157 extern struct domain inetdomain;
158 struct protosw in_stf_protosw = {
159 .pr_type = SOCK_RAW,
160 .pr_domain = &inetdomain,
161 .pr_protocol = IPPROTO_IPV6,
162 .pr_flags = PR_ATOMIC|PR_ADDR,
163 .pr_input = in_stf_input,
164 .pr_output = (pr_output_t *)rip_output,
165 .pr_ctloutput = rip_ctloutput,
166 .pr_usrreqs = &rip_usrreqs
167 };
168
169 static char *stfnames[] = {"stf0", "stf", "6to4", NULL};
170
171 static int stfmodevent(module_t, int, void *);
172 static int stf_encapcheck(const struct mbuf *, int, int, void *);
173 static struct in6_ifaddr *stf_getsrcifa6(struct ifnet *);
174 static int stf_output(struct ifnet *, struct mbuf *, struct sockaddr *,
175 struct rtentry *);
176 static int isrfc1918addr(struct in_addr *);
177 static int stf_checkaddr4(struct stf_softc *, struct in_addr *,
178 struct ifnet *);
179 static int stf_checkaddr6(struct stf_softc *, struct in6_addr *,
180 struct ifnet *);
181 static void stf_rtrequest(int, struct rtentry *, struct rt_addrinfo *);
182 static int stf_ioctl(struct ifnet *, u_long, caddr_t);
183
184 static int stf_clone_match(struct if_clone *, const char *);
185 static int stf_clone_create(struct if_clone *, char *, size_t);
186 static int stf_clone_destroy(struct if_clone *, struct ifnet *);
187 struct if_clone stf_cloner = IFC_CLONE_INITIALIZER(STFNAME, NULL, 0,
188 NULL, stf_clone_match, stf_clone_create, stf_clone_destroy);
189
190 static int
191 stf_clone_match(struct if_clone *ifc, const char *name)
192 {
193 int i;
194
195 for(i = 0; stfnames[i] != NULL; i++) {
196 if (strcmp(stfnames[i], name) == 0)
197 return (1);
198 }
199
200 return (0);
201 }
202
203 static int
204 stf_clone_create(struct if_clone *ifc, char *name, size_t len)
205 {
206 int err, unit;
207 struct stf_softc *sc;
208 struct ifnet *ifp;
209
210 /*
211 * We can only have one unit, but since unit allocation is
212 * already locked, we use it to keep from allocating extra
213 * interfaces.
214 */
215 unit = STFUNIT;
216 err = ifc_alloc_unit(ifc, &unit);
217 if (err != 0)
218 return (err);
219
220 sc = malloc(sizeof(struct stf_softc), M_STF, M_WAITOK | M_ZERO);
221 ifp = STF2IFP(sc) = if_alloc(IFT_STF);
222 if (ifp == NULL) {
223 free(sc, M_STF);
224 ifc_free_unit(ifc, unit);
225 return (ENOSPC);
226 }
227 ifp->if_softc = sc;
228
229 /*
230 * Set the name manually rather then using if_initname because
231 * we don't conform to the default naming convention for interfaces.
232 */
233 strlcpy(ifp->if_xname, name, IFNAMSIZ);
234 ifp->if_dname = ifc->ifc_name;
235 ifp->if_dunit = IF_DUNIT_NONE;
236
237 sc->encap_cookie = encap_attach_func(AF_INET, IPPROTO_IPV6,
238 stf_encapcheck, &in_stf_protosw, sc);
239 if (sc->encap_cookie == NULL) {
240 if_printf(ifp, "attach failed\n");
241 free(sc, M_STF);
242 ifc_free_unit(ifc, unit);
243 return (ENOMEM);
244 }
245
246 ifp->if_mtu = IPV6_MMTU;
247 ifp->if_ioctl = stf_ioctl;
248 ifp->if_output = stf_output;
249 ifp->if_snd.ifq_maxlen = IFQ_MAXLEN;
250 if_attach(ifp);
251 bpfattach(ifp, DLT_NULL, sizeof(u_int32_t));
252 mtx_lock(&stf_mtx);
253 LIST_INSERT_HEAD(&stf_softc_list, sc, sc_list);
254 mtx_unlock(&stf_mtx);
255 return (0);
256 }
257
258 static void
259 stf_destroy(struct stf_softc *sc)
260 {
261 int err;
262
263 err = encap_detach(sc->encap_cookie);
264 KASSERT(err == 0, ("Unexpected error detaching encap_cookie"));
265 bpfdetach(STF2IFP(sc));
266 if_detach(STF2IFP(sc));
267 if_free(STF2IFP(sc));
268
269 free(sc, M_STF);
270 }
271
272 static int
273 stf_clone_destroy(struct if_clone *ifc, struct ifnet *ifp)
274 {
275 struct stf_softc *sc = ifp->if_softc;
276
277 mtx_lock(&stf_mtx);
278 LIST_REMOVE(sc, sc_list);
279 mtx_unlock(&stf_mtx);
280
281 stf_destroy(sc);
282 ifc_free_unit(ifc, STFUNIT);
283
284 return (0);
285 }
286
287 static int
288 stfmodevent(mod, type, data)
289 module_t mod;
290 int type;
291 void *data;
292 {
293 struct stf_softc *sc;
294
295 switch (type) {
296 case MOD_LOAD:
297 mtx_init(&stf_mtx, "stf_mtx", NULL, MTX_DEF);
298 LIST_INIT(&stf_softc_list);
299 if_clone_attach(&stf_cloner);
300
301 break;
302 case MOD_UNLOAD:
303 if_clone_detach(&stf_cloner);
304
305 mtx_lock(&stf_mtx);
306 while ((sc = LIST_FIRST(&stf_softc_list)) != NULL) {
307 LIST_REMOVE(sc, sc_list);
308 mtx_unlock(&stf_mtx);
309 stf_destroy(sc);
310 mtx_lock(&stf_mtx);
311 }
312 mtx_unlock(&stf_mtx);
313 mtx_destroy(&stf_mtx);
314 break;
315 default:
316 return (EOPNOTSUPP);
317 }
318
319 return (0);
320 }
321
322 static moduledata_t stf_mod = {
323 "if_stf",
324 stfmodevent,
325 0
326 };
327
328 DECLARE_MODULE(if_stf, stf_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
329
330 static int
331 stf_encapcheck(m, off, proto, arg)
332 const struct mbuf *m;
333 int off;
334 int proto;
335 void *arg;
336 {
337 struct ip ip;
338 struct in6_ifaddr *ia6;
339 struct stf_softc *sc;
340 struct in_addr a, b, mask;
341
342 sc = (struct stf_softc *)arg;
343 if (sc == NULL)
344 return 0;
345
346 if ((STF2IFP(sc)->if_flags & IFF_UP) == 0)
347 return 0;
348
349 /* IFF_LINK0 means "no decapsulation" */
350 if ((STF2IFP(sc)->if_flags & IFF_LINK0) != 0)
351 return 0;
352
353 if (proto != IPPROTO_IPV6)
354 return 0;
355
356 /* LINTED const cast */
357 m_copydata((struct mbuf *)(uintptr_t)m, 0, sizeof(ip), (caddr_t)&ip);
358
359 if (ip.ip_v != 4)
360 return 0;
361
362 ia6 = stf_getsrcifa6(STF2IFP(sc));
363 if (ia6 == NULL)
364 return 0;
365
366 /*
367 * check if IPv4 dst matches the IPv4 address derived from the
368 * local 6to4 address.
369 * success on: dst = 10.1.1.1, ia6->ia_addr = 2002:0a01:0101:...
370 */
371 if (bcmp(GET_V4(&ia6->ia_addr.sin6_addr), &ip.ip_dst,
372 sizeof(ip.ip_dst)) != 0)
373 return 0;
374
375 /*
376 * check if IPv4 src matches the IPv4 address derived from the
377 * local 6to4 address masked by prefixmask.
378 * success on: src = 10.1.1.1, ia6->ia_addr = 2002:0a00:.../24
379 * fail on: src = 10.1.1.1, ia6->ia_addr = 2002:0b00:.../24
380 */
381 bzero(&a, sizeof(a));
382 bcopy(GET_V4(&ia6->ia_addr.sin6_addr), &a, sizeof(a));
383 bcopy(GET_V4(&ia6->ia_prefixmask.sin6_addr), &mask, sizeof(mask));
384 a.s_addr &= mask.s_addr;
385 b = ip.ip_src;
386 b.s_addr &= mask.s_addr;
387 if (a.s_addr != b.s_addr)
388 return 0;
389
390 /* stf interface makes single side match only */
391 return 32;
392 }
393
394 static struct in6_ifaddr *
395 stf_getsrcifa6(ifp)
396 struct ifnet *ifp;
397 {
398 struct ifaddr *ia;
399 struct in_ifaddr *ia4;
400 struct sockaddr_in6 *sin6;
401 struct in_addr in;
402
403 for (ia = TAILQ_FIRST(&ifp->if_addrlist);
404 ia;
405 ia = TAILQ_NEXT(ia, ifa_list))
406 {
407 if (ia->ifa_addr == NULL)
408 continue;
409 if (ia->ifa_addr->sa_family != AF_INET6)
410 continue;
411 sin6 = (struct sockaddr_in6 *)ia->ifa_addr;
412 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr))
413 continue;
414
415 bcopy(GET_V4(&sin6->sin6_addr), &in, sizeof(in));
416 LIST_FOREACH(ia4, INADDR_HASH(in.s_addr), ia_hash)
417 if (ia4->ia_addr.sin_addr.s_addr == in.s_addr)
418 break;
419 if (ia4 == NULL)
420 continue;
421
422 return (struct in6_ifaddr *)ia;
423 }
424
425 return NULL;
426 }
427
428 static int
429 stf_output(ifp, m, dst, rt)
430 struct ifnet *ifp;
431 struct mbuf *m;
432 struct sockaddr *dst;
433 struct rtentry *rt;
434 {
435 struct stf_softc *sc;
436 struct sockaddr_in6 *dst6;
437 struct in_addr in4;
438 caddr_t ptr;
439 struct sockaddr_in *dst4;
440 u_int8_t tos;
441 struct ip *ip;
442 struct ip6_hdr *ip6;
443 struct in6_ifaddr *ia6;
444 u_int32_t af;
445 #ifdef MAC
446 int error;
447
448 error = mac_check_ifnet_transmit(ifp, m);
449 if (error) {
450 m_freem(m);
451 return (error);
452 }
453 #endif
454
455 sc = ifp->if_softc;
456 dst6 = (struct sockaddr_in6 *)dst;
457
458 /* just in case */
459 if ((ifp->if_flags & IFF_UP) == 0) {
460 m_freem(m);
461 ifp->if_oerrors++;
462 return ENETDOWN;
463 }
464
465 /*
466 * If we don't have an ip4 address that match my inner ip6 address,
467 * we shouldn't generate output. Without this check, we'll end up
468 * using wrong IPv4 source.
469 */
470 ia6 = stf_getsrcifa6(ifp);
471 if (ia6 == NULL) {
472 m_freem(m);
473 ifp->if_oerrors++;
474 return ENETDOWN;
475 }
476
477 if (m->m_len < sizeof(*ip6)) {
478 m = m_pullup(m, sizeof(*ip6));
479 if (!m) {
480 ifp->if_oerrors++;
481 return ENOBUFS;
482 }
483 }
484 ip6 = mtod(m, struct ip6_hdr *);
485 tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
486
487 /*
488 * BPF writes need to be handled specially.
489 * This is a null operation, nothing here checks dst->sa_family.
490 */
491 if (dst->sa_family == AF_UNSPEC) {
492 bcopy(dst->sa_data, &af, sizeof(af));
493 dst->sa_family = af;
494 }
495
496 /*
497 * Pickup the right outer dst addr from the list of candidates.
498 * ip6_dst has priority as it may be able to give us shorter IPv4 hops.
499 */
500 ptr = NULL;
501 if (IN6_IS_ADDR_6TO4(&ip6->ip6_dst))
502 ptr = GET_V4(&ip6->ip6_dst);
503 else if (IN6_IS_ADDR_6TO4(&dst6->sin6_addr))
504 ptr = GET_V4(&dst6->sin6_addr);
505 else {
506 m_freem(m);
507 ifp->if_oerrors++;
508 return ENETUNREACH;
509 }
510 bcopy(ptr, &in4, sizeof(in4));
511
512 if (bpf_peers_present(ifp->if_bpf)) {
513 /*
514 * We need to prepend the address family as
515 * a four byte field. Cons up a dummy header
516 * to pacify bpf. This is safe because bpf
517 * will only read from the mbuf (i.e., it won't
518 * try to free it or keep a pointer a to it).
519 */
520 af = AF_INET6;
521 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m);
522 }
523
524 M_PREPEND(m, sizeof(struct ip), M_DONTWAIT);
525 if (m && m->m_len < sizeof(struct ip))
526 m = m_pullup(m, sizeof(struct ip));
527 if (m == NULL) {
528 ifp->if_oerrors++;
529 return ENOBUFS;
530 }
531 ip = mtod(m, struct ip *);
532
533 bzero(ip, sizeof(*ip));
534
535 bcopy(GET_V4(&((struct sockaddr_in6 *)&ia6->ia_addr)->sin6_addr),
536 &ip->ip_src, sizeof(ip->ip_src));
537 bcopy(&in4, &ip->ip_dst, sizeof(ip->ip_dst));
538 ip->ip_p = IPPROTO_IPV6;
539 ip->ip_ttl = ip_stf_ttl;
540 ip->ip_len = m->m_pkthdr.len; /*host order*/
541 if (ifp->if_flags & IFF_LINK1)
542 ip_ecn_ingress(ECN_ALLOWED, &ip->ip_tos, &tos);
543 else
544 ip_ecn_ingress(ECN_NOCARE, &ip->ip_tos, &tos);
545
546 /*
547 * XXXRW: Locking of sc_ro required.
548 */
549 dst4 = (struct sockaddr_in *)&sc->sc_ro.ro_dst;
550 if (dst4->sin_family != AF_INET ||
551 bcmp(&dst4->sin_addr, &ip->ip_dst, sizeof(ip->ip_dst)) != 0) {
552 /* cache route doesn't match */
553 dst4->sin_family = AF_INET;
554 dst4->sin_len = sizeof(struct sockaddr_in);
555 bcopy(&ip->ip_dst, &dst4->sin_addr, sizeof(dst4->sin_addr));
556 if (sc->sc_ro.ro_rt) {
557 RTFREE(sc->sc_ro.ro_rt);
558 sc->sc_ro.ro_rt = NULL;
559 }
560 }
561
562 if (sc->sc_ro.ro_rt == NULL) {
563 rtalloc(&sc->sc_ro);
564 if (sc->sc_ro.ro_rt == NULL) {
565 m_freem(m);
566 ifp->if_oerrors++;
567 return ENETUNREACH;
568 }
569 }
570
571 ifp->if_opackets++;
572 return ip_output(m, NULL, &sc->sc_ro, 0, NULL, NULL);
573 }
574
575 static int
576 isrfc1918addr(in)
577 struct in_addr *in;
578 {
579 /*
580 * returns 1 if private address range:
581 * 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16
582 */
583 if ((ntohl(in->s_addr) & 0xff000000) >> 24 == 10 ||
584 (ntohl(in->s_addr) & 0xfff00000) >> 16 == 172 * 256 + 16 ||
585 (ntohl(in->s_addr) & 0xffff0000) >> 16 == 192 * 256 + 168)
586 return 1;
587
588 return 0;
589 }
590
591 static int
592 stf_checkaddr4(sc, in, inifp)
593 struct stf_softc *sc;
594 struct in_addr *in;
595 struct ifnet *inifp; /* incoming interface */
596 {
597 struct in_ifaddr *ia4;
598
599 /*
600 * reject packets with the following address:
601 * 224.0.0.0/4 0.0.0.0/8 127.0.0.0/8 255.0.0.0/8
602 */
603 if (IN_MULTICAST(ntohl(in->s_addr)))
604 return -1;
605 switch ((ntohl(in->s_addr) & 0xff000000) >> 24) {
606 case 0: case 127: case 255:
607 return -1;
608 }
609
610 /*
611 * reject packets with private address range.
612 * (requirement from RFC3056 section 2 1st paragraph)
613 */
614 if (isrfc1918addr(in))
615 return -1;
616
617 /*
618 * reject packets with broadcast
619 */
620 for (ia4 = TAILQ_FIRST(&in_ifaddrhead);
621 ia4;
622 ia4 = TAILQ_NEXT(ia4, ia_link))
623 {
624 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0)
625 continue;
626 if (in->s_addr == ia4->ia_broadaddr.sin_addr.s_addr)
627 return -1;
628 }
629
630 /*
631 * perform ingress filter
632 */
633 if (sc && (STF2IFP(sc)->if_flags & IFF_LINK2) == 0 && inifp) {
634 struct sockaddr_in sin;
635 struct rtentry *rt;
636
637 bzero(&sin, sizeof(sin));
638 sin.sin_family = AF_INET;
639 sin.sin_len = sizeof(struct sockaddr_in);
640 sin.sin_addr = *in;
641 rt = rtalloc1((struct sockaddr *)&sin, 0, 0UL);
642 if (!rt || rt->rt_ifp != inifp) {
643 #if 0
644 log(LOG_WARNING, "%s: packet from 0x%x dropped "
645 "due to ingress filter\n", if_name(STF2IFP(sc)),
646 (u_int32_t)ntohl(sin.sin_addr.s_addr));
647 #endif
648 if (rt)
649 rtfree(rt);
650 return -1;
651 }
652 rtfree(rt);
653 }
654
655 return 0;
656 }
657
658 static int
659 stf_checkaddr6(sc, in6, inifp)
660 struct stf_softc *sc;
661 struct in6_addr *in6;
662 struct ifnet *inifp; /* incoming interface */
663 {
664 /*
665 * check 6to4 addresses
666 */
667 if (IN6_IS_ADDR_6TO4(in6)) {
668 struct in_addr in4;
669 bcopy(GET_V4(in6), &in4, sizeof(in4));
670 return stf_checkaddr4(sc, &in4, inifp);
671 }
672
673 /*
674 * reject anything that look suspicious. the test is implemented
675 * in ip6_input too, but we check here as well to
676 * (1) reject bad packets earlier, and
677 * (2) to be safe against future ip6_input change.
678 */
679 if (IN6_IS_ADDR_V4COMPAT(in6) || IN6_IS_ADDR_V4MAPPED(in6))
680 return -1;
681
682 return 0;
683 }
684
685 void
686 in_stf_input(m, off)
687 struct mbuf *m;
688 int off;
689 {
690 int proto;
691 struct stf_softc *sc;
692 struct ip *ip;
693 struct ip6_hdr *ip6;
694 u_int8_t otos, itos;
695 struct ifnet *ifp;
696
697 proto = mtod(m, struct ip *)->ip_p;
698
699 if (proto != IPPROTO_IPV6) {
700 m_freem(m);
701 return;
702 }
703
704 ip = mtod(m, struct ip *);
705
706 sc = (struct stf_softc *)encap_getarg(m);
707
708 if (sc == NULL || (STF2IFP(sc)->if_flags & IFF_UP) == 0) {
709 m_freem(m);
710 return;
711 }
712
713 ifp = STF2IFP(sc);
714
715 #ifdef MAC
716 mac_create_mbuf_from_ifnet(ifp, m);
717 #endif
718
719 /*
720 * perform sanity check against outer src/dst.
721 * for source, perform ingress filter as well.
722 */
723 if (stf_checkaddr4(sc, &ip->ip_dst, NULL) < 0 ||
724 stf_checkaddr4(sc, &ip->ip_src, m->m_pkthdr.rcvif) < 0) {
725 m_freem(m);
726 return;
727 }
728
729 otos = ip->ip_tos;
730 m_adj(m, off);
731
732 if (m->m_len < sizeof(*ip6)) {
733 m = m_pullup(m, sizeof(*ip6));
734 if (!m)
735 return;
736 }
737 ip6 = mtod(m, struct ip6_hdr *);
738
739 /*
740 * perform sanity check against inner src/dst.
741 * for source, perform ingress filter as well.
742 */
743 if (stf_checkaddr6(sc, &ip6->ip6_dst, NULL) < 0 ||
744 stf_checkaddr6(sc, &ip6->ip6_src, m->m_pkthdr.rcvif) < 0) {
745 m_freem(m);
746 return;
747 }
748
749 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
750 if ((ifp->if_flags & IFF_LINK1) != 0)
751 ip_ecn_egress(ECN_ALLOWED, &otos, &itos);
752 else
753 ip_ecn_egress(ECN_NOCARE, &otos, &itos);
754 ip6->ip6_flow &= ~htonl(0xff << 20);
755 ip6->ip6_flow |= htonl((u_int32_t)itos << 20);
756
757 m->m_pkthdr.rcvif = ifp;
758
759 if (bpf_peers_present(ifp->if_bpf)) {
760 /*
761 * We need to prepend the address family as
762 * a four byte field. Cons up a dummy header
763 * to pacify bpf. This is safe because bpf
764 * will only read from the mbuf (i.e., it won't
765 * try to free it or keep a pointer a to it).
766 */
767 u_int32_t af = AF_INET6;
768 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m);
769 }
770
771 /*
772 * Put the packet to the network layer input queue according to the
773 * specified address family.
774 * See net/if_gif.c for possible issues with packet processing
775 * reorder due to extra queueing.
776 */
777 ifp->if_ipackets++;
778 ifp->if_ibytes += m->m_pkthdr.len;
779 netisr_dispatch(NETISR_IPV6, m);
780 }
781
782 /* ARGSUSED */
783 static void
784 stf_rtrequest(cmd, rt, info)
785 int cmd;
786 struct rtentry *rt;
787 struct rt_addrinfo *info;
788 {
789 RT_LOCK_ASSERT(rt);
790 rt->rt_rmx.rmx_mtu = IPV6_MMTU;
791 }
792
793 static int
794 stf_ioctl(ifp, cmd, data)
795 struct ifnet *ifp;
796 u_long cmd;
797 caddr_t data;
798 {
799 struct ifaddr *ifa;
800 struct ifreq *ifr;
801 struct sockaddr_in6 *sin6;
802 struct in_addr addr;
803 int error;
804
805 error = 0;
806 switch (cmd) {
807 case SIOCSIFADDR:
808 ifa = (struct ifaddr *)data;
809 if (ifa == NULL || ifa->ifa_addr->sa_family != AF_INET6) {
810 error = EAFNOSUPPORT;
811 break;
812 }
813 sin6 = (struct sockaddr_in6 *)ifa->ifa_addr;
814 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) {
815 error = EINVAL;
816 break;
817 }
818 bcopy(GET_V4(&sin6->sin6_addr), &addr, sizeof(addr));
819 if (isrfc1918addr(&addr)) {
820 error = EINVAL;
821 break;
822 }
823
824 ifa->ifa_rtrequest = stf_rtrequest;
825 ifp->if_flags |= IFF_UP;
826 break;
827
828 case SIOCADDMULTI:
829 case SIOCDELMULTI:
830 ifr = (struct ifreq *)data;
831 if (ifr && ifr->ifr_addr.sa_family == AF_INET6)
832 ;
833 else
834 error = EAFNOSUPPORT;
835 break;
836
837 default:
838 error = EINVAL;
839 break;
840 }
841
842 return error;
843 }
Cache object: db6a12d24371ae828417408d9b02ddfe
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