1 /*-
2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
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.
16 *
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
27 * SUCH DAMAGE.
28 *
29 * $KAME: ip6_input.c,v 1.259 2002/01/21 04:58:09 jinmei Exp $
30 */
31
32 /*-
33 * Copyright (c) 1982, 1986, 1988, 1993
34 * The Regents of the University of California. All rights reserved.
35 *
36 * Redistribution and use in source and binary forms, with or without
37 * modification, are permitted provided that the following conditions
38 * are met:
39 * 1. Redistributions of source code must retain the above copyright
40 * notice, this list of conditions and the following disclaimer.
41 * 2. Redistributions in binary form must reproduce the above copyright
42 * notice, this list of conditions and the following disclaimer in the
43 * documentation and/or other materials provided with the distribution.
44 * 4. Neither the name of the University nor the names of its contributors
45 * may be used to endorse or promote products derived from this software
46 * without specific prior written permission.
47 *
48 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
49 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
50 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
51 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
52 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
53 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
54 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
55 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
56 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
57 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
58 * SUCH DAMAGE.
59 *
60 * @(#)ip_input.c 8.2 (Berkeley) 1/4/94
61 */
62
63 #include <sys/cdefs.h>
64 __FBSDID("$FreeBSD: releng/11.1/sys/netinet6/ip6_input.c 315514 2017-03-18 22:04:20Z ae $");
65
66 #include "opt_inet.h"
67 #include "opt_inet6.h"
68 #include "opt_ipsec.h"
69 #include "opt_route.h"
70 #include "opt_rss.h"
71
72 #include <sys/param.h>
73 #include <sys/systm.h>
74 #include <sys/hhook.h>
75 #include <sys/malloc.h>
76 #include <sys/mbuf.h>
77 #include <sys/proc.h>
78 #include <sys/domain.h>
79 #include <sys/protosw.h>
80 #include <sys/sdt.h>
81 #include <sys/socket.h>
82 #include <sys/socketvar.h>
83 #include <sys/errno.h>
84 #include <sys/time.h>
85 #include <sys/kernel.h>
86 #include <sys/lock.h>
87 #include <sys/rmlock.h>
88 #include <sys/syslog.h>
89 #include <sys/sysctl.h>
90
91 #include <net/if.h>
92 #include <net/if_var.h>
93 #include <net/if_types.h>
94 #include <net/if_dl.h>
95 #include <net/route.h>
96 #include <net/netisr.h>
97 #include <net/rss_config.h>
98 #include <net/pfil.h>
99 #include <net/vnet.h>
100
101 #include <netinet/in.h>
102 #include <netinet/in_kdtrace.h>
103 #include <netinet/ip_var.h>
104 #include <netinet/in_systm.h>
105 #include <net/if_llatbl.h>
106 #ifdef INET
107 #include <netinet/ip.h>
108 #include <netinet/ip_icmp.h>
109 #endif /* INET */
110 #include <netinet/ip6.h>
111 #include <netinet6/in6_var.h>
112 #include <netinet6/ip6_var.h>
113 #include <netinet/in_pcb.h>
114 #include <netinet/icmp6.h>
115 #include <netinet6/scope6_var.h>
116 #include <netinet6/in6_ifattach.h>
117 #include <netinet6/mld6_var.h>
118 #include <netinet6/nd6.h>
119 #include <netinet6/in6_rss.h>
120
121 #include <netipsec/ipsec_support.h>
122
123 #include <netinet6/ip6protosw.h>
124
125 extern struct domain inet6domain;
126
127 u_char ip6_protox[IPPROTO_MAX];
128 VNET_DEFINE(struct in6_ifaddrhead, in6_ifaddrhead);
129 VNET_DEFINE(struct in6_ifaddrlisthead *, in6_ifaddrhashtbl);
130 VNET_DEFINE(u_long, in6_ifaddrhmask);
131
132 static struct netisr_handler ip6_nh = {
133 .nh_name = "ip6",
134 .nh_handler = ip6_input,
135 .nh_proto = NETISR_IPV6,
136 #ifdef RSS
137 .nh_m2cpuid = rss_soft_m2cpuid_v6,
138 .nh_policy = NETISR_POLICY_CPU,
139 .nh_dispatch = NETISR_DISPATCH_HYBRID,
140 #else
141 .nh_policy = NETISR_POLICY_FLOW,
142 #endif
143 };
144
145 static int
146 sysctl_netinet6_intr_queue_maxlen(SYSCTL_HANDLER_ARGS)
147 {
148 int error, qlimit;
149
150 netisr_getqlimit(&ip6_nh, &qlimit);
151 error = sysctl_handle_int(oidp, &qlimit, 0, req);
152 if (error || !req->newptr)
153 return (error);
154 if (qlimit < 1)
155 return (EINVAL);
156 return (netisr_setqlimit(&ip6_nh, qlimit));
157 }
158 SYSCTL_DECL(_net_inet6_ip6);
159 SYSCTL_PROC(_net_inet6_ip6, IPV6CTL_INTRQMAXLEN, intr_queue_maxlen,
160 CTLTYPE_INT|CTLFLAG_RW, 0, 0, sysctl_netinet6_intr_queue_maxlen, "I",
161 "Maximum size of the IPv6 input queue");
162
163 #ifdef RSS
164 static struct netisr_handler ip6_direct_nh = {
165 .nh_name = "ip6_direct",
166 .nh_handler = ip6_direct_input,
167 .nh_proto = NETISR_IPV6_DIRECT,
168 .nh_m2cpuid = rss_soft_m2cpuid_v6,
169 .nh_policy = NETISR_POLICY_CPU,
170 .nh_dispatch = NETISR_DISPATCH_HYBRID,
171 };
172
173 static int
174 sysctl_netinet6_intr_direct_queue_maxlen(SYSCTL_HANDLER_ARGS)
175 {
176 int error, qlimit;
177
178 netisr_getqlimit(&ip6_direct_nh, &qlimit);
179 error = sysctl_handle_int(oidp, &qlimit, 0, req);
180 if (error || !req->newptr)
181 return (error);
182 if (qlimit < 1)
183 return (EINVAL);
184 return (netisr_setqlimit(&ip6_direct_nh, qlimit));
185 }
186 SYSCTL_PROC(_net_inet6_ip6, IPV6CTL_INTRDQMAXLEN, intr_direct_queue_maxlen,
187 CTLTYPE_INT|CTLFLAG_RW, 0, 0, sysctl_netinet6_intr_direct_queue_maxlen,
188 "I", "Maximum size of the IPv6 direct input queue");
189
190 #endif
191
192 VNET_DEFINE(struct pfil_head, inet6_pfil_hook);
193
194 VNET_PCPUSTAT_DEFINE(struct ip6stat, ip6stat);
195 VNET_PCPUSTAT_SYSINIT(ip6stat);
196 #ifdef VIMAGE
197 VNET_PCPUSTAT_SYSUNINIT(ip6stat);
198 #endif /* VIMAGE */
199
200 struct rmlock in6_ifaddr_lock;
201 RM_SYSINIT(in6_ifaddr_lock, &in6_ifaddr_lock, "in6_ifaddr_lock");
202
203 static int ip6_hopopts_input(u_int32_t *, u_int32_t *, struct mbuf **, int *);
204 #ifdef PULLDOWN_TEST
205 static struct mbuf *ip6_pullexthdr(struct mbuf *, size_t, int);
206 #endif
207
208 /*
209 * IP6 initialization: fill in IP6 protocol switch table.
210 * All protocols not implemented in kernel go to raw IP6 protocol handler.
211 */
212 void
213 ip6_init(void)
214 {
215 struct protosw *pr;
216 int i;
217
218 TUNABLE_INT_FETCH("net.inet6.ip6.auto_linklocal",
219 &V_ip6_auto_linklocal);
220 TUNABLE_INT_FETCH("net.inet6.ip6.accept_rtadv", &V_ip6_accept_rtadv);
221 TUNABLE_INT_FETCH("net.inet6.ip6.no_radr", &V_ip6_no_radr);
222
223 TAILQ_INIT(&V_in6_ifaddrhead);
224 V_in6_ifaddrhashtbl = hashinit(IN6ADDR_NHASH, M_IFADDR,
225 &V_in6_ifaddrhmask);
226
227 /* Initialize packet filter hooks. */
228 V_inet6_pfil_hook.ph_type = PFIL_TYPE_AF;
229 V_inet6_pfil_hook.ph_af = AF_INET6;
230 if ((i = pfil_head_register(&V_inet6_pfil_hook)) != 0)
231 printf("%s: WARNING: unable to register pfil hook, "
232 "error %d\n", __func__, i);
233
234 if (hhook_head_register(HHOOK_TYPE_IPSEC_IN, AF_INET6,
235 &V_ipsec_hhh_in[HHOOK_IPSEC_INET6],
236 HHOOK_WAITOK | HHOOK_HEADISINVNET) != 0)
237 printf("%s: WARNING: unable to register input helper hook\n",
238 __func__);
239 if (hhook_head_register(HHOOK_TYPE_IPSEC_OUT, AF_INET6,
240 &V_ipsec_hhh_out[HHOOK_IPSEC_INET6],
241 HHOOK_WAITOK | HHOOK_HEADISINVNET) != 0)
242 printf("%s: WARNING: unable to register output helper hook\n",
243 __func__);
244
245 scope6_init();
246 addrsel_policy_init();
247 nd6_init();
248 frag6_init();
249
250 V_ip6_desync_factor = arc4random() % MAX_TEMP_DESYNC_FACTOR;
251
252 /* Skip global initialization stuff for non-default instances. */
253 #ifdef VIMAGE
254 if (!IS_DEFAULT_VNET(curvnet)) {
255 netisr_register_vnet(&ip6_nh);
256 #ifdef RSS
257 netisr_register_vnet(&ip6_direct_nh);
258 #endif
259 return;
260 }
261 #endif
262
263 pr = pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW);
264 if (pr == NULL)
265 panic("ip6_init");
266
267 /* Initialize the entire ip6_protox[] array to IPPROTO_RAW. */
268 for (i = 0; i < IPPROTO_MAX; i++)
269 ip6_protox[i] = pr - inet6sw;
270 /*
271 * Cycle through IP protocols and put them into the appropriate place
272 * in ip6_protox[].
273 */
274 for (pr = inet6domain.dom_protosw;
275 pr < inet6domain.dom_protoswNPROTOSW; pr++)
276 if (pr->pr_domain->dom_family == PF_INET6 &&
277 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) {
278 /* Be careful to only index valid IP protocols. */
279 if (pr->pr_protocol < IPPROTO_MAX)
280 ip6_protox[pr->pr_protocol] = pr - inet6sw;
281 }
282
283 netisr_register(&ip6_nh);
284 #ifdef RSS
285 netisr_register(&ip6_direct_nh);
286 #endif
287 }
288
289 /*
290 * The protocol to be inserted into ip6_protox[] must be already registered
291 * in inet6sw[], either statically or through pf_proto_register().
292 */
293 int
294 ip6proto_register(short ip6proto)
295 {
296 struct protosw *pr;
297
298 /* Sanity checks. */
299 if (ip6proto <= 0 || ip6proto >= IPPROTO_MAX)
300 return (EPROTONOSUPPORT);
301
302 /*
303 * The protocol slot must not be occupied by another protocol
304 * already. An index pointing to IPPROTO_RAW is unused.
305 */
306 pr = pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW);
307 if (pr == NULL)
308 return (EPFNOSUPPORT);
309 if (ip6_protox[ip6proto] != pr - inet6sw) /* IPPROTO_RAW */
310 return (EEXIST);
311
312 /*
313 * Find the protocol position in inet6sw[] and set the index.
314 */
315 for (pr = inet6domain.dom_protosw;
316 pr < inet6domain.dom_protoswNPROTOSW; pr++) {
317 if (pr->pr_domain->dom_family == PF_INET6 &&
318 pr->pr_protocol && pr->pr_protocol == ip6proto) {
319 ip6_protox[pr->pr_protocol] = pr - inet6sw;
320 return (0);
321 }
322 }
323 return (EPROTONOSUPPORT);
324 }
325
326 int
327 ip6proto_unregister(short ip6proto)
328 {
329 struct protosw *pr;
330
331 /* Sanity checks. */
332 if (ip6proto <= 0 || ip6proto >= IPPROTO_MAX)
333 return (EPROTONOSUPPORT);
334
335 /* Check if the protocol was indeed registered. */
336 pr = pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW);
337 if (pr == NULL)
338 return (EPFNOSUPPORT);
339 if (ip6_protox[ip6proto] == pr - inet6sw) /* IPPROTO_RAW */
340 return (ENOENT);
341
342 /* Reset the protocol slot to IPPROTO_RAW. */
343 ip6_protox[ip6proto] = pr - inet6sw;
344 return (0);
345 }
346
347 #ifdef VIMAGE
348 static void
349 ip6_destroy(void *unused __unused)
350 {
351 struct ifaddr *ifa, *nifa;
352 struct ifnet *ifp;
353 int error;
354
355 #ifdef RSS
356 netisr_unregister_vnet(&ip6_direct_nh);
357 #endif
358 netisr_unregister_vnet(&ip6_nh);
359
360 if ((error = pfil_head_unregister(&V_inet6_pfil_hook)) != 0)
361 printf("%s: WARNING: unable to unregister pfil hook, "
362 "error %d\n", __func__, error);
363 error = hhook_head_deregister(V_ipsec_hhh_in[HHOOK_IPSEC_INET6]);
364 if (error != 0) {
365 printf("%s: WARNING: unable to deregister input helper hook "
366 "type HHOOK_TYPE_IPSEC_IN, id HHOOK_IPSEC_INET6: "
367 "error %d returned\n", __func__, error);
368 }
369 error = hhook_head_deregister(V_ipsec_hhh_out[HHOOK_IPSEC_INET6]);
370 if (error != 0) {
371 printf("%s: WARNING: unable to deregister output helper hook "
372 "type HHOOK_TYPE_IPSEC_OUT, id HHOOK_IPSEC_INET6: "
373 "error %d returned\n", __func__, error);
374 }
375
376 /* Cleanup addresses. */
377 IFNET_RLOCK();
378 TAILQ_FOREACH(ifp, &V_ifnet, if_link) {
379 /* Cannot lock here - lock recursion. */
380 /* IF_ADDR_LOCK(ifp); */
381 TAILQ_FOREACH_SAFE(ifa, &ifp->if_addrhead, ifa_link, nifa) {
382
383 if (ifa->ifa_addr->sa_family != AF_INET6)
384 continue;
385 in6_purgeaddr(ifa);
386 }
387 /* IF_ADDR_UNLOCK(ifp); */
388 in6_ifdetach_destroy(ifp);
389 mld_domifdetach(ifp);
390 /* Make sure any routes are gone as well. */
391 rt_flushifroutes_af(ifp, AF_INET6);
392 }
393 IFNET_RUNLOCK();
394
395 nd6_destroy();
396 in6_ifattach_destroy();
397
398 hashdestroy(V_in6_ifaddrhashtbl, M_IFADDR, V_in6_ifaddrhmask);
399 }
400
401 VNET_SYSUNINIT(inet6, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, ip6_destroy, NULL);
402 #endif
403
404 static int
405 ip6_input_hbh(struct mbuf *m, uint32_t *plen, uint32_t *rtalert, int *off,
406 int *nxt, int *ours)
407 {
408 struct ip6_hdr *ip6;
409 struct ip6_hbh *hbh;
410
411 if (ip6_hopopts_input(plen, rtalert, &m, off)) {
412 #if 0 /*touches NULL pointer*/
413 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard);
414 #endif
415 goto out; /* m have already been freed */
416 }
417
418 /* adjust pointer */
419 ip6 = mtod(m, struct ip6_hdr *);
420
421 /*
422 * if the payload length field is 0 and the next header field
423 * indicates Hop-by-Hop Options header, then a Jumbo Payload
424 * option MUST be included.
425 */
426 if (ip6->ip6_plen == 0 && *plen == 0) {
427 /*
428 * Note that if a valid jumbo payload option is
429 * contained, ip6_hopopts_input() must set a valid
430 * (non-zero) payload length to the variable plen.
431 */
432 IP6STAT_INC(ip6s_badoptions);
433 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard);
434 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr);
435 icmp6_error(m, ICMP6_PARAM_PROB,
436 ICMP6_PARAMPROB_HEADER,
437 (caddr_t)&ip6->ip6_plen - (caddr_t)ip6);
438 goto out;
439 }
440 #ifndef PULLDOWN_TEST
441 /* ip6_hopopts_input() ensures that mbuf is contiguous */
442 hbh = (struct ip6_hbh *)(ip6 + 1);
443 #else
444 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr),
445 sizeof(struct ip6_hbh));
446 if (hbh == NULL) {
447 IP6STAT_INC(ip6s_tooshort);
448 goto out;
449 }
450 #endif
451 *nxt = hbh->ip6h_nxt;
452
453 /*
454 * If we are acting as a router and the packet contains a
455 * router alert option, see if we know the option value.
456 * Currently, we only support the option value for MLD, in which
457 * case we should pass the packet to the multicast routing
458 * daemon.
459 */
460 if (*rtalert != ~0) {
461 switch (*rtalert) {
462 case IP6OPT_RTALERT_MLD:
463 if (V_ip6_forwarding)
464 *ours = 1;
465 break;
466 default:
467 /*
468 * RFC2711 requires unrecognized values must be
469 * silently ignored.
470 */
471 break;
472 }
473 }
474
475 return (0);
476
477 out:
478 return (1);
479 }
480
481 #ifdef RSS
482 /*
483 * IPv6 direct input routine.
484 *
485 * This is called when reinjecting completed fragments where
486 * all of the previous checking and book-keeping has been done.
487 */
488 void
489 ip6_direct_input(struct mbuf *m)
490 {
491 int off, nxt;
492 int nest;
493 struct m_tag *mtag;
494 struct ip6_direct_ctx *ip6dc;
495
496 mtag = m_tag_locate(m, MTAG_ABI_IPV6, IPV6_TAG_DIRECT, NULL);
497 KASSERT(mtag != NULL, ("Reinjected packet w/o direct ctx tag!"));
498
499 ip6dc = (struct ip6_direct_ctx *)(mtag + 1);
500 nxt = ip6dc->ip6dc_nxt;
501 off = ip6dc->ip6dc_off;
502
503 nest = 0;
504
505 m_tag_delete(m, mtag);
506
507 while (nxt != IPPROTO_DONE) {
508 if (V_ip6_hdrnestlimit && (++nest > V_ip6_hdrnestlimit)) {
509 IP6STAT_INC(ip6s_toomanyhdr);
510 goto bad;
511 }
512
513 /*
514 * protection against faulty packet - there should be
515 * more sanity checks in header chain processing.
516 */
517 if (m->m_pkthdr.len < off) {
518 IP6STAT_INC(ip6s_tooshort);
519 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated);
520 goto bad;
521 }
522
523 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
524 if (IPSEC_ENABLED(ipv6)) {
525 if (IPSEC_INPUT(ipv6, m, off, nxt) != 0)
526 return;
527 }
528 #endif /* IPSEC */
529
530 nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &off, nxt);
531 }
532 return;
533 bad:
534 m_freem(m);
535 }
536 #endif
537
538 void
539 ip6_input(struct mbuf *m)
540 {
541 struct in6_addr odst;
542 struct ip6_hdr *ip6;
543 struct in6_ifaddr *ia;
544 struct ifnet *rcvif;
545 u_int32_t plen;
546 u_int32_t rtalert = ~0;
547 int off = sizeof(struct ip6_hdr), nest;
548 int nxt, ours = 0;
549 int srcrt = 0;
550
551 /*
552 * Drop the packet if IPv6 operation is disabled on the interface.
553 */
554 rcvif = m->m_pkthdr.rcvif;
555 if ((ND_IFINFO(rcvif)->flags & ND6_IFF_IFDISABLED))
556 goto bad;
557
558 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
559 /*
560 * should the inner packet be considered authentic?
561 * see comment in ah4_input().
562 * NB: m cannot be NULL when passed to the input routine
563 */
564
565 m->m_flags &= ~M_AUTHIPHDR;
566 m->m_flags &= ~M_AUTHIPDGM;
567
568 #endif /* IPSEC */
569
570 if (m->m_flags & M_FASTFWD_OURS) {
571 /*
572 * Firewall changed destination to local.
573 */
574 m->m_flags &= ~M_FASTFWD_OURS;
575 ours = 1;
576 ip6 = mtod(m, struct ip6_hdr *);
577 goto hbhcheck;
578 }
579
580 /*
581 * mbuf statistics
582 */
583 if (m->m_flags & M_EXT) {
584 if (m->m_next)
585 IP6STAT_INC(ip6s_mext2m);
586 else
587 IP6STAT_INC(ip6s_mext1);
588 } else {
589 if (m->m_next) {
590 if (m->m_flags & M_LOOP) {
591 IP6STAT_INC(ip6s_m2m[V_loif->if_index]);
592 } else if (rcvif->if_index < IP6S_M2MMAX)
593 IP6STAT_INC(ip6s_m2m[rcvif->if_index]);
594 else
595 IP6STAT_INC(ip6s_m2m[0]);
596 } else
597 IP6STAT_INC(ip6s_m1);
598 }
599
600 in6_ifstat_inc(rcvif, ifs6_in_receive);
601 IP6STAT_INC(ip6s_total);
602
603 #ifndef PULLDOWN_TEST
604 /*
605 * L2 bridge code and some other code can return mbuf chain
606 * that does not conform to KAME requirement. too bad.
607 * XXX: fails to join if interface MTU > MCLBYTES. jumbogram?
608 */
609 if (m && m->m_next != NULL && m->m_pkthdr.len < MCLBYTES) {
610 struct mbuf *n;
611
612 if (m->m_pkthdr.len > MHLEN)
613 n = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
614 else
615 n = m_gethdr(M_NOWAIT, MT_DATA);
616 if (n == NULL)
617 goto bad;
618
619 m_move_pkthdr(n, m);
620 m_copydata(m, 0, n->m_pkthdr.len, mtod(n, caddr_t));
621 n->m_len = n->m_pkthdr.len;
622 m_freem(m);
623 m = n;
624 }
625 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), /* nothing */);
626 #endif
627
628 if (m->m_len < sizeof(struct ip6_hdr)) {
629 if ((m = m_pullup(m, sizeof(struct ip6_hdr))) == NULL) {
630 IP6STAT_INC(ip6s_toosmall);
631 in6_ifstat_inc(rcvif, ifs6_in_hdrerr);
632 goto bad;
633 }
634 }
635
636 ip6 = mtod(m, struct ip6_hdr *);
637 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
638 IP6STAT_INC(ip6s_badvers);
639 in6_ifstat_inc(rcvif, ifs6_in_hdrerr);
640 goto bad;
641 }
642
643 IP6STAT_INC(ip6s_nxthist[ip6->ip6_nxt]);
644 IP_PROBE(receive, NULL, NULL, ip6, rcvif, NULL, ip6);
645
646 /*
647 * Check against address spoofing/corruption.
648 */
649 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src) ||
650 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst)) {
651 /*
652 * XXX: "badscope" is not very suitable for a multicast source.
653 */
654 IP6STAT_INC(ip6s_badscope);
655 in6_ifstat_inc(rcvif, ifs6_in_addrerr);
656 goto bad;
657 }
658 if (IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst) &&
659 !(m->m_flags & M_LOOP)) {
660 /*
661 * In this case, the packet should come from the loopback
662 * interface. However, we cannot just check the if_flags,
663 * because ip6_mloopback() passes the "actual" interface
664 * as the outgoing/incoming interface.
665 */
666 IP6STAT_INC(ip6s_badscope);
667 in6_ifstat_inc(rcvif, ifs6_in_addrerr);
668 goto bad;
669 }
670 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) &&
671 IPV6_ADDR_MC_SCOPE(&ip6->ip6_dst) == 0) {
672 /*
673 * RFC4291 2.7:
674 * Nodes must not originate a packet to a multicast address
675 * whose scop field contains the reserved value 0; if such
676 * a packet is received, it must be silently dropped.
677 */
678 IP6STAT_INC(ip6s_badscope);
679 in6_ifstat_inc(rcvif, ifs6_in_addrerr);
680 goto bad;
681 }
682 #ifdef ALTQ
683 if (altq_input != NULL && (*altq_input)(m, AF_INET6) == 0) {
684 /* packet is dropped by traffic conditioner */
685 return;
686 }
687 #endif
688 /*
689 * The following check is not documented in specs. A malicious
690 * party may be able to use IPv4 mapped addr to confuse tcp/udp stack
691 * and bypass security checks (act as if it was from 127.0.0.1 by using
692 * IPv6 src ::ffff:127.0.0.1). Be cautious.
693 *
694 * This check chokes if we are in an SIIT cloud. As none of BSDs
695 * support IPv4-less kernel compilation, we cannot support SIIT
696 * environment at all. So, it makes more sense for us to reject any
697 * malicious packets for non-SIIT environment, than try to do a
698 * partial support for SIIT environment.
699 */
700 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) ||
701 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) {
702 IP6STAT_INC(ip6s_badscope);
703 in6_ifstat_inc(rcvif, ifs6_in_addrerr);
704 goto bad;
705 }
706 #if 0
707 /*
708 * Reject packets with IPv4 compatible addresses (auto tunnel).
709 *
710 * The code forbids auto tunnel relay case in RFC1933 (the check is
711 * stronger than RFC1933). We may want to re-enable it if mech-xx
712 * is revised to forbid relaying case.
713 */
714 if (IN6_IS_ADDR_V4COMPAT(&ip6->ip6_src) ||
715 IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) {
716 IP6STAT_INC(ip6s_badscope);
717 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr);
718 goto bad;
719 }
720 #endif
721 /*
722 * Try to forward the packet, but if we fail continue.
723 * ip6_tryforward() does inbound and outbound packet firewall
724 * processing. If firewall has decided that destination becomes
725 * our local address, it sets M_FASTFWD_OURS flag. In this
726 * case skip another inbound firewall processing and update
727 * ip6 pointer.
728 */
729 if (V_ip6_forwarding != 0
730 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
731 && (!IPSEC_ENABLED(ipv6) ||
732 IPSEC_CAPS(ipv6, m, IPSEC_CAP_OPERABLE) == 0)
733 #endif
734 ) {
735 if ((m = ip6_tryforward(m)) == NULL)
736 return;
737 if (m->m_flags & M_FASTFWD_OURS) {
738 m->m_flags &= ~M_FASTFWD_OURS;
739 ours = 1;
740 ip6 = mtod(m, struct ip6_hdr *);
741 goto hbhcheck;
742 }
743 }
744 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
745 /*
746 * Bypass packet filtering for packets previously handled by IPsec.
747 */
748 if (IPSEC_ENABLED(ipv6) &&
749 IPSEC_CAPS(ipv6, m, IPSEC_CAP_BYPASS_FILTER) != 0)
750 goto passin;
751 #endif
752 /*
753 * Run through list of hooks for input packets.
754 *
755 * NB: Beware of the destination address changing
756 * (e.g. by NAT rewriting). When this happens,
757 * tell ip6_forward to do the right thing.
758 */
759
760 /* Jump over all PFIL processing if hooks are not active. */
761 if (!PFIL_HOOKED(&V_inet6_pfil_hook))
762 goto passin;
763
764 odst = ip6->ip6_dst;
765 if (pfil_run_hooks(&V_inet6_pfil_hook, &m,
766 m->m_pkthdr.rcvif, PFIL_IN, NULL))
767 return;
768 if (m == NULL) /* consumed by filter */
769 return;
770 ip6 = mtod(m, struct ip6_hdr *);
771 srcrt = !IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst);
772
773 if (m->m_flags & M_FASTFWD_OURS) {
774 m->m_flags &= ~M_FASTFWD_OURS;
775 ours = 1;
776 goto hbhcheck;
777 }
778 if ((m->m_flags & M_IP6_NEXTHOP) &&
779 m_tag_find(m, PACKET_TAG_IPFORWARD, NULL) != NULL) {
780 /*
781 * Directly ship the packet on. This allows forwarding
782 * packets originally destined to us to some other directly
783 * connected host.
784 */
785 ip6_forward(m, 1);
786 return;
787 }
788
789 passin:
790 /*
791 * Disambiguate address scope zones (if there is ambiguity).
792 * We first make sure that the original source or destination address
793 * is not in our internal form for scoped addresses. Such addresses
794 * are not necessarily invalid spec-wise, but we cannot accept them due
795 * to the usage conflict.
796 * in6_setscope() then also checks and rejects the cases where src or
797 * dst are the loopback address and the receiving interface
798 * is not loopback.
799 */
800 if (in6_clearscope(&ip6->ip6_src) || in6_clearscope(&ip6->ip6_dst)) {
801 IP6STAT_INC(ip6s_badscope); /* XXX */
802 goto bad;
803 }
804 if (in6_setscope(&ip6->ip6_src, rcvif, NULL) ||
805 in6_setscope(&ip6->ip6_dst, rcvif, NULL)) {
806 IP6STAT_INC(ip6s_badscope);
807 goto bad;
808 }
809 /*
810 * Multicast check. Assume packet is for us to avoid
811 * prematurely taking locks.
812 */
813 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
814 ours = 1;
815 in6_ifstat_inc(rcvif, ifs6_in_mcast);
816 goto hbhcheck;
817 }
818 /*
819 * Unicast check
820 * XXX: For now we keep link-local IPv6 addresses with embedded
821 * scope zone id, therefore we use zero zoneid here.
822 */
823 ia = in6ifa_ifwithaddr(&ip6->ip6_dst, 0 /* XXX */);
824 if (ia != NULL) {
825 if (ia->ia6_flags & IN6_IFF_NOTREADY) {
826 char ip6bufs[INET6_ADDRSTRLEN];
827 char ip6bufd[INET6_ADDRSTRLEN];
828 /* address is not ready, so discard the packet. */
829 nd6log((LOG_INFO,
830 "ip6_input: packet to an unready address %s->%s\n",
831 ip6_sprintf(ip6bufs, &ip6->ip6_src),
832 ip6_sprintf(ip6bufd, &ip6->ip6_dst)));
833 ifa_free(&ia->ia_ifa);
834 goto bad;
835 }
836 /* Count the packet in the ip address stats */
837 counter_u64_add(ia->ia_ifa.ifa_ipackets, 1);
838 counter_u64_add(ia->ia_ifa.ifa_ibytes, m->m_pkthdr.len);
839 ifa_free(&ia->ia_ifa);
840 ours = 1;
841 goto hbhcheck;
842 }
843
844 /*
845 * Now there is no reason to process the packet if it's not our own
846 * and we're not a router.
847 */
848 if (!V_ip6_forwarding) {
849 IP6STAT_INC(ip6s_cantforward);
850 goto bad;
851 }
852
853 hbhcheck:
854 /*
855 * Process Hop-by-Hop options header if it's contained.
856 * m may be modified in ip6_hopopts_input().
857 * If a JumboPayload option is included, plen will also be modified.
858 */
859 plen = (u_int32_t)ntohs(ip6->ip6_plen);
860 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) {
861 if (ip6_input_hbh(m, &plen, &rtalert, &off, &nxt, &ours) != 0)
862 return;
863 } else
864 nxt = ip6->ip6_nxt;
865
866 /*
867 * Use mbuf flags to propagate Router Alert option to
868 * ICMPv6 layer, as hop-by-hop options have been stripped.
869 */
870 if (rtalert != ~0)
871 m->m_flags |= M_RTALERT_MLD;
872
873 /*
874 * Check that the amount of data in the buffers
875 * is as at least much as the IPv6 header would have us expect.
876 * Trim mbufs if longer than we expect.
877 * Drop packet if shorter than we expect.
878 */
879 if (m->m_pkthdr.len - sizeof(struct ip6_hdr) < plen) {
880 IP6STAT_INC(ip6s_tooshort);
881 in6_ifstat_inc(rcvif, ifs6_in_truncated);
882 goto bad;
883 }
884 if (m->m_pkthdr.len > sizeof(struct ip6_hdr) + plen) {
885 if (m->m_len == m->m_pkthdr.len) {
886 m->m_len = sizeof(struct ip6_hdr) + plen;
887 m->m_pkthdr.len = sizeof(struct ip6_hdr) + plen;
888 } else
889 m_adj(m, sizeof(struct ip6_hdr) + plen - m->m_pkthdr.len);
890 }
891
892 /*
893 * Forward if desirable.
894 */
895 if (V_ip6_mrouter &&
896 IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
897 /*
898 * If we are acting as a multicast router, all
899 * incoming multicast packets are passed to the
900 * kernel-level multicast forwarding function.
901 * The packet is returned (relatively) intact; if
902 * ip6_mforward() returns a non-zero value, the packet
903 * must be discarded, else it may be accepted below.
904 *
905 * XXX TODO: Check hlim and multicast scope here to avoid
906 * unnecessarily calling into ip6_mforward().
907 */
908 if (ip6_mforward && ip6_mforward(ip6, rcvif, m)) {
909 IP6STAT_INC(ip6s_cantforward);
910 goto bad;
911 }
912 } else if (!ours) {
913 ip6_forward(m, srcrt);
914 return;
915 }
916
917 ip6 = mtod(m, struct ip6_hdr *);
918
919 /*
920 * Malicious party may be able to use IPv4 mapped addr to confuse
921 * tcp/udp stack and bypass security checks (act as if it was from
922 * 127.0.0.1 by using IPv6 src ::ffff:127.0.0.1). Be cautious.
923 *
924 * For SIIT end node behavior, you may want to disable the check.
925 * However, you will become vulnerable to attacks using IPv4 mapped
926 * source.
927 */
928 if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) ||
929 IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) {
930 IP6STAT_INC(ip6s_badscope);
931 in6_ifstat_inc(rcvif, ifs6_in_addrerr);
932 goto bad;
933 }
934
935 /*
936 * Tell launch routine the next header
937 */
938 IP6STAT_INC(ip6s_delivered);
939 in6_ifstat_inc(rcvif, ifs6_in_deliver);
940 nest = 0;
941
942 while (nxt != IPPROTO_DONE) {
943 if (V_ip6_hdrnestlimit && (++nest > V_ip6_hdrnestlimit)) {
944 IP6STAT_INC(ip6s_toomanyhdr);
945 goto bad;
946 }
947
948 /*
949 * protection against faulty packet - there should be
950 * more sanity checks in header chain processing.
951 */
952 if (m->m_pkthdr.len < off) {
953 IP6STAT_INC(ip6s_tooshort);
954 in6_ifstat_inc(rcvif, ifs6_in_truncated);
955 goto bad;
956 }
957
958 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
959 if (IPSEC_ENABLED(ipv6)) {
960 if (IPSEC_INPUT(ipv6, m, off, nxt) != 0)
961 return;
962 }
963 #endif /* IPSEC */
964
965 nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &off, nxt);
966 }
967 return;
968 bad:
969 in6_ifstat_inc(rcvif, ifs6_in_discard);
970 if (m != NULL)
971 m_freem(m);
972 }
973
974 /*
975 * Hop-by-Hop options header processing. If a valid jumbo payload option is
976 * included, the real payload length will be stored in plenp.
977 *
978 * rtalertp - XXX: should be stored more smart way
979 */
980 static int
981 ip6_hopopts_input(u_int32_t *plenp, u_int32_t *rtalertp,
982 struct mbuf **mp, int *offp)
983 {
984 struct mbuf *m = *mp;
985 int off = *offp, hbhlen;
986 struct ip6_hbh *hbh;
987
988 /* validation of the length of the header */
989 #ifndef PULLDOWN_TEST
990 IP6_EXTHDR_CHECK(m, off, sizeof(*hbh), -1);
991 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off);
992 hbhlen = (hbh->ip6h_len + 1) << 3;
993
994 IP6_EXTHDR_CHECK(m, off, hbhlen, -1);
995 hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off);
996 #else
997 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m,
998 sizeof(struct ip6_hdr), sizeof(struct ip6_hbh));
999 if (hbh == NULL) {
1000 IP6STAT_INC(ip6s_tooshort);
1001 return -1;
1002 }
1003 hbhlen = (hbh->ip6h_len + 1) << 3;
1004 IP6_EXTHDR_GET(hbh, struct ip6_hbh *, m, sizeof(struct ip6_hdr),
1005 hbhlen);
1006 if (hbh == NULL) {
1007 IP6STAT_INC(ip6s_tooshort);
1008 return -1;
1009 }
1010 #endif
1011 off += hbhlen;
1012 hbhlen -= sizeof(struct ip6_hbh);
1013 if (ip6_process_hopopts(m, (u_int8_t *)hbh + sizeof(struct ip6_hbh),
1014 hbhlen, rtalertp, plenp) < 0)
1015 return (-1);
1016
1017 *offp = off;
1018 *mp = m;
1019 return (0);
1020 }
1021
1022 /*
1023 * Search header for all Hop-by-hop options and process each option.
1024 * This function is separate from ip6_hopopts_input() in order to
1025 * handle a case where the sending node itself process its hop-by-hop
1026 * options header. In such a case, the function is called from ip6_output().
1027 *
1028 * The function assumes that hbh header is located right after the IPv6 header
1029 * (RFC2460 p7), opthead is pointer into data content in m, and opthead to
1030 * opthead + hbhlen is located in contiguous memory region.
1031 */
1032 int
1033 ip6_process_hopopts(struct mbuf *m, u_int8_t *opthead, int hbhlen,
1034 u_int32_t *rtalertp, u_int32_t *plenp)
1035 {
1036 struct ip6_hdr *ip6;
1037 int optlen = 0;
1038 u_int8_t *opt = opthead;
1039 u_int16_t rtalert_val;
1040 u_int32_t jumboplen;
1041 const int erroff = sizeof(struct ip6_hdr) + sizeof(struct ip6_hbh);
1042
1043 for (; hbhlen > 0; hbhlen -= optlen, opt += optlen) {
1044 switch (*opt) {
1045 case IP6OPT_PAD1:
1046 optlen = 1;
1047 break;
1048 case IP6OPT_PADN:
1049 if (hbhlen < IP6OPT_MINLEN) {
1050 IP6STAT_INC(ip6s_toosmall);
1051 goto bad;
1052 }
1053 optlen = *(opt + 1) + 2;
1054 break;
1055 case IP6OPT_ROUTER_ALERT:
1056 /* XXX may need check for alignment */
1057 if (hbhlen < IP6OPT_RTALERT_LEN) {
1058 IP6STAT_INC(ip6s_toosmall);
1059 goto bad;
1060 }
1061 if (*(opt + 1) != IP6OPT_RTALERT_LEN - 2) {
1062 /* XXX stat */
1063 icmp6_error(m, ICMP6_PARAM_PROB,
1064 ICMP6_PARAMPROB_HEADER,
1065 erroff + opt + 1 - opthead);
1066 return (-1);
1067 }
1068 optlen = IP6OPT_RTALERT_LEN;
1069 bcopy((caddr_t)(opt + 2), (caddr_t)&rtalert_val, 2);
1070 *rtalertp = ntohs(rtalert_val);
1071 break;
1072 case IP6OPT_JUMBO:
1073 /* XXX may need check for alignment */
1074 if (hbhlen < IP6OPT_JUMBO_LEN) {
1075 IP6STAT_INC(ip6s_toosmall);
1076 goto bad;
1077 }
1078 if (*(opt + 1) != IP6OPT_JUMBO_LEN - 2) {
1079 /* XXX stat */
1080 icmp6_error(m, ICMP6_PARAM_PROB,
1081 ICMP6_PARAMPROB_HEADER,
1082 erroff + opt + 1 - opthead);
1083 return (-1);
1084 }
1085 optlen = IP6OPT_JUMBO_LEN;
1086
1087 /*
1088 * IPv6 packets that have non 0 payload length
1089 * must not contain a jumbo payload option.
1090 */
1091 ip6 = mtod(m, struct ip6_hdr *);
1092 if (ip6->ip6_plen) {
1093 IP6STAT_INC(ip6s_badoptions);
1094 icmp6_error(m, ICMP6_PARAM_PROB,
1095 ICMP6_PARAMPROB_HEADER,
1096 erroff + opt - opthead);
1097 return (-1);
1098 }
1099
1100 /*
1101 * We may see jumbolen in unaligned location, so
1102 * we'd need to perform bcopy().
1103 */
1104 bcopy(opt + 2, &jumboplen, sizeof(jumboplen));
1105 jumboplen = (u_int32_t)htonl(jumboplen);
1106
1107 #if 1
1108 /*
1109 * if there are multiple jumbo payload options,
1110 * *plenp will be non-zero and the packet will be
1111 * rejected.
1112 * the behavior may need some debate in ipngwg -
1113 * multiple options does not make sense, however,
1114 * there's no explicit mention in specification.
1115 */
1116 if (*plenp != 0) {
1117 IP6STAT_INC(ip6s_badoptions);
1118 icmp6_error(m, ICMP6_PARAM_PROB,
1119 ICMP6_PARAMPROB_HEADER,
1120 erroff + opt + 2 - opthead);
1121 return (-1);
1122 }
1123 #endif
1124
1125 /*
1126 * jumbo payload length must be larger than 65535.
1127 */
1128 if (jumboplen <= IPV6_MAXPACKET) {
1129 IP6STAT_INC(ip6s_badoptions);
1130 icmp6_error(m, ICMP6_PARAM_PROB,
1131 ICMP6_PARAMPROB_HEADER,
1132 erroff + opt + 2 - opthead);
1133 return (-1);
1134 }
1135 *plenp = jumboplen;
1136
1137 break;
1138 default: /* unknown option */
1139 if (hbhlen < IP6OPT_MINLEN) {
1140 IP6STAT_INC(ip6s_toosmall);
1141 goto bad;
1142 }
1143 optlen = ip6_unknown_opt(opt, m,
1144 erroff + opt - opthead);
1145 if (optlen == -1)
1146 return (-1);
1147 optlen += 2;
1148 break;
1149 }
1150 }
1151
1152 return (0);
1153
1154 bad:
1155 m_freem(m);
1156 return (-1);
1157 }
1158
1159 /*
1160 * Unknown option processing.
1161 * The third argument `off' is the offset from the IPv6 header to the option,
1162 * which is necessary if the IPv6 header the and option header and IPv6 header
1163 * is not contiguous in order to return an ICMPv6 error.
1164 */
1165 int
1166 ip6_unknown_opt(u_int8_t *optp, struct mbuf *m, int off)
1167 {
1168 struct ip6_hdr *ip6;
1169
1170 switch (IP6OPT_TYPE(*optp)) {
1171 case IP6OPT_TYPE_SKIP: /* ignore the option */
1172 return ((int)*(optp + 1));
1173 case IP6OPT_TYPE_DISCARD: /* silently discard */
1174 m_freem(m);
1175 return (-1);
1176 case IP6OPT_TYPE_FORCEICMP: /* send ICMP even if multicasted */
1177 IP6STAT_INC(ip6s_badoptions);
1178 icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, off);
1179 return (-1);
1180 case IP6OPT_TYPE_ICMP: /* send ICMP if not multicasted */
1181 IP6STAT_INC(ip6s_badoptions);
1182 ip6 = mtod(m, struct ip6_hdr *);
1183 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) ||
1184 (m->m_flags & (M_BCAST|M_MCAST)))
1185 m_freem(m);
1186 else
1187 icmp6_error(m, ICMP6_PARAM_PROB,
1188 ICMP6_PARAMPROB_OPTION, off);
1189 return (-1);
1190 }
1191
1192 m_freem(m); /* XXX: NOTREACHED */
1193 return (-1);
1194 }
1195
1196 /*
1197 * Create the "control" list for this pcb.
1198 * These functions will not modify mbuf chain at all.
1199 *
1200 * With KAME mbuf chain restriction:
1201 * The routine will be called from upper layer handlers like tcp6_input().
1202 * Thus the routine assumes that the caller (tcp6_input) have already
1203 * called IP6_EXTHDR_CHECK() and all the extension headers are located in the
1204 * very first mbuf on the mbuf chain.
1205 *
1206 * ip6_savecontrol_v4 will handle those options that are possible to be
1207 * set on a v4-mapped socket.
1208 * ip6_savecontrol will directly call ip6_savecontrol_v4 to handle those
1209 * options and handle the v6-only ones itself.
1210 */
1211 struct mbuf **
1212 ip6_savecontrol_v4(struct inpcb *inp, struct mbuf *m, struct mbuf **mp,
1213 int *v4only)
1214 {
1215 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1216
1217 #ifdef SO_TIMESTAMP
1218 if ((inp->inp_socket->so_options & SO_TIMESTAMP) != 0) {
1219 struct timeval tv;
1220
1221 microtime(&tv);
1222 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv),
1223 SCM_TIMESTAMP, SOL_SOCKET);
1224 if (*mp)
1225 mp = &(*mp)->m_next;
1226 }
1227 #endif
1228
1229 #define IS2292(inp, x, y) (((inp)->inp_flags & IN6P_RFC2292) ? (x) : (y))
1230 /* RFC 2292 sec. 5 */
1231 if ((inp->inp_flags & IN6P_PKTINFO) != 0) {
1232 struct in6_pktinfo pi6;
1233
1234 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
1235 #ifdef INET
1236 struct ip *ip;
1237
1238 ip = mtod(m, struct ip *);
1239 pi6.ipi6_addr.s6_addr32[0] = 0;
1240 pi6.ipi6_addr.s6_addr32[1] = 0;
1241 pi6.ipi6_addr.s6_addr32[2] = IPV6_ADDR_INT32_SMP;
1242 pi6.ipi6_addr.s6_addr32[3] = ip->ip_dst.s_addr;
1243 #else
1244 /* We won't hit this code */
1245 bzero(&pi6.ipi6_addr, sizeof(struct in6_addr));
1246 #endif
1247 } else {
1248 bcopy(&ip6->ip6_dst, &pi6.ipi6_addr, sizeof(struct in6_addr));
1249 in6_clearscope(&pi6.ipi6_addr); /* XXX */
1250 }
1251 pi6.ipi6_ifindex =
1252 (m && m->m_pkthdr.rcvif) ? m->m_pkthdr.rcvif->if_index : 0;
1253
1254 *mp = sbcreatecontrol((caddr_t) &pi6,
1255 sizeof(struct in6_pktinfo),
1256 IS2292(inp, IPV6_2292PKTINFO, IPV6_PKTINFO), IPPROTO_IPV6);
1257 if (*mp)
1258 mp = &(*mp)->m_next;
1259 }
1260
1261 if ((inp->inp_flags & IN6P_HOPLIMIT) != 0) {
1262 int hlim;
1263
1264 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
1265 #ifdef INET
1266 struct ip *ip;
1267
1268 ip = mtod(m, struct ip *);
1269 hlim = ip->ip_ttl;
1270 #else
1271 /* We won't hit this code */
1272 hlim = 0;
1273 #endif
1274 } else {
1275 hlim = ip6->ip6_hlim & 0xff;
1276 }
1277 *mp = sbcreatecontrol((caddr_t) &hlim, sizeof(int),
1278 IS2292(inp, IPV6_2292HOPLIMIT, IPV6_HOPLIMIT),
1279 IPPROTO_IPV6);
1280 if (*mp)
1281 mp = &(*mp)->m_next;
1282 }
1283
1284 if ((inp->inp_flags & IN6P_TCLASS) != 0) {
1285 int tclass;
1286
1287 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
1288 #ifdef INET
1289 struct ip *ip;
1290
1291 ip = mtod(m, struct ip *);
1292 tclass = ip->ip_tos;
1293 #else
1294 /* We won't hit this code */
1295 tclass = 0;
1296 #endif
1297 } else {
1298 u_int32_t flowinfo;
1299
1300 flowinfo = (u_int32_t)ntohl(ip6->ip6_flow & IPV6_FLOWINFO_MASK);
1301 flowinfo >>= 20;
1302 tclass = flowinfo & 0xff;
1303 }
1304 *mp = sbcreatecontrol((caddr_t) &tclass, sizeof(int),
1305 IPV6_TCLASS, IPPROTO_IPV6);
1306 if (*mp)
1307 mp = &(*mp)->m_next;
1308 }
1309
1310 if (v4only != NULL) {
1311 if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
1312 *v4only = 1;
1313 } else {
1314 *v4only = 0;
1315 }
1316 }
1317
1318 return (mp);
1319 }
1320
1321 void
1322 ip6_savecontrol(struct inpcb *in6p, struct mbuf *m, struct mbuf **mp)
1323 {
1324 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1325 int v4only = 0;
1326
1327 mp = ip6_savecontrol_v4(in6p, m, mp, &v4only);
1328 if (v4only)
1329 return;
1330
1331 /*
1332 * IPV6_HOPOPTS socket option. Recall that we required super-user
1333 * privilege for the option (see ip6_ctloutput), but it might be too
1334 * strict, since there might be some hop-by-hop options which can be
1335 * returned to normal user.
1336 * See also RFC 2292 section 6 (or RFC 3542 section 8).
1337 */
1338 if ((in6p->inp_flags & IN6P_HOPOPTS) != 0) {
1339 /*
1340 * Check if a hop-by-hop options header is contatined in the
1341 * received packet, and if so, store the options as ancillary
1342 * data. Note that a hop-by-hop options header must be
1343 * just after the IPv6 header, which is assured through the
1344 * IPv6 input processing.
1345 */
1346 if (ip6->ip6_nxt == IPPROTO_HOPOPTS) {
1347 struct ip6_hbh *hbh;
1348 int hbhlen = 0;
1349 #ifdef PULLDOWN_TEST
1350 struct mbuf *ext;
1351 #endif
1352
1353 #ifndef PULLDOWN_TEST
1354 hbh = (struct ip6_hbh *)(ip6 + 1);
1355 hbhlen = (hbh->ip6h_len + 1) << 3;
1356 #else
1357 ext = ip6_pullexthdr(m, sizeof(struct ip6_hdr),
1358 ip6->ip6_nxt);
1359 if (ext == NULL) {
1360 IP6STAT_INC(ip6s_tooshort);
1361 return;
1362 }
1363 hbh = mtod(ext, struct ip6_hbh *);
1364 hbhlen = (hbh->ip6h_len + 1) << 3;
1365 if (hbhlen != ext->m_len) {
1366 m_freem(ext);
1367 IP6STAT_INC(ip6s_tooshort);
1368 return;
1369 }
1370 #endif
1371
1372 /*
1373 * XXX: We copy the whole header even if a
1374 * jumbo payload option is included, the option which
1375 * is to be removed before returning according to
1376 * RFC2292.
1377 * Note: this constraint is removed in RFC3542
1378 */
1379 *mp = sbcreatecontrol((caddr_t)hbh, hbhlen,
1380 IS2292(in6p, IPV6_2292HOPOPTS, IPV6_HOPOPTS),
1381 IPPROTO_IPV6);
1382 if (*mp)
1383 mp = &(*mp)->m_next;
1384 #ifdef PULLDOWN_TEST
1385 m_freem(ext);
1386 #endif
1387 }
1388 }
1389
1390 if ((in6p->inp_flags & (IN6P_RTHDR | IN6P_DSTOPTS)) != 0) {
1391 int nxt = ip6->ip6_nxt, off = sizeof(struct ip6_hdr);
1392
1393 /*
1394 * Search for destination options headers or routing
1395 * header(s) through the header chain, and stores each
1396 * header as ancillary data.
1397 * Note that the order of the headers remains in
1398 * the chain of ancillary data.
1399 */
1400 while (1) { /* is explicit loop prevention necessary? */
1401 struct ip6_ext *ip6e = NULL;
1402 int elen;
1403 #ifdef PULLDOWN_TEST
1404 struct mbuf *ext = NULL;
1405 #endif
1406
1407 /*
1408 * if it is not an extension header, don't try to
1409 * pull it from the chain.
1410 */
1411 switch (nxt) {
1412 case IPPROTO_DSTOPTS:
1413 case IPPROTO_ROUTING:
1414 case IPPROTO_HOPOPTS:
1415 case IPPROTO_AH: /* is it possible? */
1416 break;
1417 default:
1418 goto loopend;
1419 }
1420
1421 #ifndef PULLDOWN_TEST
1422 if (off + sizeof(*ip6e) > m->m_len)
1423 goto loopend;
1424 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + off);
1425 if (nxt == IPPROTO_AH)
1426 elen = (ip6e->ip6e_len + 2) << 2;
1427 else
1428 elen = (ip6e->ip6e_len + 1) << 3;
1429 if (off + elen > m->m_len)
1430 goto loopend;
1431 #else
1432 ext = ip6_pullexthdr(m, off, nxt);
1433 if (ext == NULL) {
1434 IP6STAT_INC(ip6s_tooshort);
1435 return;
1436 }
1437 ip6e = mtod(ext, struct ip6_ext *);
1438 if (nxt == IPPROTO_AH)
1439 elen = (ip6e->ip6e_len + 2) << 2;
1440 else
1441 elen = (ip6e->ip6e_len + 1) << 3;
1442 if (elen != ext->m_len) {
1443 m_freem(ext);
1444 IP6STAT_INC(ip6s_tooshort);
1445 return;
1446 }
1447 #endif
1448
1449 switch (nxt) {
1450 case IPPROTO_DSTOPTS:
1451 if (!(in6p->inp_flags & IN6P_DSTOPTS))
1452 break;
1453
1454 *mp = sbcreatecontrol((caddr_t)ip6e, elen,
1455 IS2292(in6p,
1456 IPV6_2292DSTOPTS, IPV6_DSTOPTS),
1457 IPPROTO_IPV6);
1458 if (*mp)
1459 mp = &(*mp)->m_next;
1460 break;
1461 case IPPROTO_ROUTING:
1462 if (!(in6p->inp_flags & IN6P_RTHDR))
1463 break;
1464
1465 *mp = sbcreatecontrol((caddr_t)ip6e, elen,
1466 IS2292(in6p, IPV6_2292RTHDR, IPV6_RTHDR),
1467 IPPROTO_IPV6);
1468 if (*mp)
1469 mp = &(*mp)->m_next;
1470 break;
1471 case IPPROTO_HOPOPTS:
1472 case IPPROTO_AH: /* is it possible? */
1473 break;
1474
1475 default:
1476 /*
1477 * other cases have been filtered in the above.
1478 * none will visit this case. here we supply
1479 * the code just in case (nxt overwritten or
1480 * other cases).
1481 */
1482 #ifdef PULLDOWN_TEST
1483 m_freem(ext);
1484 #endif
1485 goto loopend;
1486
1487 }
1488
1489 /* proceed with the next header. */
1490 off += elen;
1491 nxt = ip6e->ip6e_nxt;
1492 ip6e = NULL;
1493 #ifdef PULLDOWN_TEST
1494 m_freem(ext);
1495 ext = NULL;
1496 #endif
1497 }
1498 loopend:
1499 ;
1500 }
1501
1502 if (in6p->inp_flags2 & INP_RECVFLOWID) {
1503 uint32_t flowid, flow_type;
1504
1505 flowid = m->m_pkthdr.flowid;
1506 flow_type = M_HASHTYPE_GET(m);
1507
1508 /*
1509 * XXX should handle the failure of one or the
1510 * other - don't populate both?
1511 */
1512 *mp = sbcreatecontrol((caddr_t) &flowid,
1513 sizeof(uint32_t), IPV6_FLOWID, IPPROTO_IPV6);
1514 if (*mp)
1515 mp = &(*mp)->m_next;
1516 *mp = sbcreatecontrol((caddr_t) &flow_type,
1517 sizeof(uint32_t), IPV6_FLOWTYPE, IPPROTO_IPV6);
1518 if (*mp)
1519 mp = &(*mp)->m_next;
1520 }
1521
1522 #ifdef RSS
1523 if (in6p->inp_flags2 & INP_RECVRSSBUCKETID) {
1524 uint32_t flowid, flow_type;
1525 uint32_t rss_bucketid;
1526
1527 flowid = m->m_pkthdr.flowid;
1528 flow_type = M_HASHTYPE_GET(m);
1529
1530 if (rss_hash2bucket(flowid, flow_type, &rss_bucketid) == 0) {
1531 *mp = sbcreatecontrol((caddr_t) &rss_bucketid,
1532 sizeof(uint32_t), IPV6_RSSBUCKETID, IPPROTO_IPV6);
1533 if (*mp)
1534 mp = &(*mp)->m_next;
1535 }
1536 }
1537 #endif
1538
1539 }
1540 #undef IS2292
1541
1542 void
1543 ip6_notify_pmtu(struct inpcb *inp, struct sockaddr_in6 *dst, u_int32_t mtu)
1544 {
1545 struct socket *so;
1546 struct mbuf *m_mtu;
1547 struct ip6_mtuinfo mtuctl;
1548
1549 KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
1550 /*
1551 * Notify the error by sending IPV6_PATHMTU ancillary data if
1552 * application wanted to know the MTU value.
1553 * NOTE: we notify disconnected sockets, because some udp
1554 * applications keep sending sockets disconnected.
1555 * NOTE: our implementation doesn't notify connected sockets that has
1556 * foreign address that is different than given destination addresses
1557 * (this is permitted by RFC 3542).
1558 */
1559 if ((inp->inp_flags & IN6P_MTU) == 0 || (
1560 !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr) &&
1561 !IN6_ARE_ADDR_EQUAL(&inp->in6p_faddr, &dst->sin6_addr)))
1562 return;
1563
1564 mtuctl.ip6m_mtu = mtu;
1565 mtuctl.ip6m_addr = *dst;
1566 if (sa6_recoverscope(&mtuctl.ip6m_addr))
1567 return;
1568
1569 if ((m_mtu = sbcreatecontrol((caddr_t)&mtuctl, sizeof(mtuctl),
1570 IPV6_PATHMTU, IPPROTO_IPV6)) == NULL)
1571 return;
1572
1573 so = inp->inp_socket;
1574 if (sbappendaddr(&so->so_rcv, (struct sockaddr *)dst, NULL, m_mtu)
1575 == 0) {
1576 m_freem(m_mtu);
1577 /* XXX: should count statistics */
1578 } else
1579 sorwakeup(so);
1580 }
1581
1582 #ifdef PULLDOWN_TEST
1583 /*
1584 * pull single extension header from mbuf chain. returns single mbuf that
1585 * contains the result, or NULL on error.
1586 */
1587 static struct mbuf *
1588 ip6_pullexthdr(struct mbuf *m, size_t off, int nxt)
1589 {
1590 struct ip6_ext ip6e;
1591 size_t elen;
1592 struct mbuf *n;
1593
1594 #ifdef DIAGNOSTIC
1595 switch (nxt) {
1596 case IPPROTO_DSTOPTS:
1597 case IPPROTO_ROUTING:
1598 case IPPROTO_HOPOPTS:
1599 case IPPROTO_AH: /* is it possible? */
1600 break;
1601 default:
1602 printf("ip6_pullexthdr: invalid nxt=%d\n", nxt);
1603 }
1604 #endif
1605
1606 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e);
1607 if (nxt == IPPROTO_AH)
1608 elen = (ip6e.ip6e_len + 2) << 2;
1609 else
1610 elen = (ip6e.ip6e_len + 1) << 3;
1611
1612 if (elen > MLEN)
1613 n = m_getcl(M_NOWAIT, MT_DATA, 0);
1614 else
1615 n = m_get(M_NOWAIT, MT_DATA);
1616 if (n == NULL)
1617 return NULL;
1618
1619 m_copydata(m, off, elen, mtod(n, caddr_t));
1620 n->m_len = elen;
1621 return n;
1622 }
1623 #endif
1624
1625 /*
1626 * Get pointer to the previous header followed by the header
1627 * currently processed.
1628 * XXX: This function supposes that
1629 * M includes all headers,
1630 * the next header field and the header length field of each header
1631 * are valid, and
1632 * the sum of each header length equals to OFF.
1633 * Because of these assumptions, this function must be called very
1634 * carefully. Moreover, it will not be used in the near future when
1635 * we develop `neater' mechanism to process extension headers.
1636 */
1637 char *
1638 ip6_get_prevhdr(const struct mbuf *m, int off)
1639 {
1640 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1641
1642 if (off == sizeof(struct ip6_hdr))
1643 return (&ip6->ip6_nxt);
1644 else {
1645 int len, nxt;
1646 struct ip6_ext *ip6e = NULL;
1647
1648 nxt = ip6->ip6_nxt;
1649 len = sizeof(struct ip6_hdr);
1650 while (len < off) {
1651 ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + len);
1652
1653 switch (nxt) {
1654 case IPPROTO_FRAGMENT:
1655 len += sizeof(struct ip6_frag);
1656 break;
1657 case IPPROTO_AH:
1658 len += (ip6e->ip6e_len + 2) << 2;
1659 break;
1660 default:
1661 len += (ip6e->ip6e_len + 1) << 3;
1662 break;
1663 }
1664 nxt = ip6e->ip6e_nxt;
1665 }
1666 if (ip6e)
1667 return (&ip6e->ip6e_nxt);
1668 else
1669 return NULL;
1670 }
1671 }
1672
1673 /*
1674 * get next header offset. m will be retained.
1675 */
1676 int
1677 ip6_nexthdr(const struct mbuf *m, int off, int proto, int *nxtp)
1678 {
1679 struct ip6_hdr ip6;
1680 struct ip6_ext ip6e;
1681 struct ip6_frag fh;
1682
1683 /* just in case */
1684 if (m == NULL)
1685 panic("ip6_nexthdr: m == NULL");
1686 if ((m->m_flags & M_PKTHDR) == 0 || m->m_pkthdr.len < off)
1687 return -1;
1688
1689 switch (proto) {
1690 case IPPROTO_IPV6:
1691 if (m->m_pkthdr.len < off + sizeof(ip6))
1692 return -1;
1693 m_copydata(m, off, sizeof(ip6), (caddr_t)&ip6);
1694 if (nxtp)
1695 *nxtp = ip6.ip6_nxt;
1696 off += sizeof(ip6);
1697 return off;
1698
1699 case IPPROTO_FRAGMENT:
1700 /*
1701 * terminate parsing if it is not the first fragment,
1702 * it does not make sense to parse through it.
1703 */
1704 if (m->m_pkthdr.len < off + sizeof(fh))
1705 return -1;
1706 m_copydata(m, off, sizeof(fh), (caddr_t)&fh);
1707 /* IP6F_OFF_MASK = 0xfff8(BigEndian), 0xf8ff(LittleEndian) */
1708 if (fh.ip6f_offlg & IP6F_OFF_MASK)
1709 return -1;
1710 if (nxtp)
1711 *nxtp = fh.ip6f_nxt;
1712 off += sizeof(struct ip6_frag);
1713 return off;
1714
1715 case IPPROTO_AH:
1716 if (m->m_pkthdr.len < off + sizeof(ip6e))
1717 return -1;
1718 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e);
1719 if (nxtp)
1720 *nxtp = ip6e.ip6e_nxt;
1721 off += (ip6e.ip6e_len + 2) << 2;
1722 return off;
1723
1724 case IPPROTO_HOPOPTS:
1725 case IPPROTO_ROUTING:
1726 case IPPROTO_DSTOPTS:
1727 if (m->m_pkthdr.len < off + sizeof(ip6e))
1728 return -1;
1729 m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e);
1730 if (nxtp)
1731 *nxtp = ip6e.ip6e_nxt;
1732 off += (ip6e.ip6e_len + 1) << 3;
1733 return off;
1734
1735 case IPPROTO_NONE:
1736 case IPPROTO_ESP:
1737 case IPPROTO_IPCOMP:
1738 /* give up */
1739 return -1;
1740
1741 default:
1742 return -1;
1743 }
1744
1745 /* NOTREACHED */
1746 }
1747
1748 /*
1749 * get offset for the last header in the chain. m will be kept untainted.
1750 */
1751 int
1752 ip6_lasthdr(const struct mbuf *m, int off, int proto, int *nxtp)
1753 {
1754 int newoff;
1755 int nxt;
1756
1757 if (!nxtp) {
1758 nxt = -1;
1759 nxtp = &nxt;
1760 }
1761 while (1) {
1762 newoff = ip6_nexthdr(m, off, proto, nxtp);
1763 if (newoff < 0)
1764 return off;
1765 else if (newoff < off)
1766 return -1; /* invalid */
1767 else if (newoff == off)
1768 return newoff;
1769
1770 off = newoff;
1771 proto = *nxtp;
1772 }
1773 }
1774
1775 /*
1776 * System control for IP6
1777 */
1778
1779 u_char inet6ctlerrmap[PRC_NCMDS] = {
1780 0, 0, 0, 0,
1781 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH,
1782 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED,
1783 EMSGSIZE, EHOSTUNREACH, 0, 0,
1784 0, 0, EHOSTUNREACH, 0,
1785 ENOPROTOOPT, ECONNREFUSED
1786 };
Cache object: a2bb60e4570db8c306e97b09ceabb9a8
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