xref: /freebsd/sys/netinet6/ip6_input.c (revision 32100375a661c1e16588ddfa7b90ca8d26cb9786)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the project nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  *	$KAME: ip6_input.c,v 1.259 2002/01/21 04:58:09 jinmei Exp $
32  */
33 
34 /*-
35  * Copyright (c) 1982, 1986, 1988, 1993
36  *	The Regents of the University of California.  All rights reserved.
37  *
38  * Redistribution and use in source and binary forms, with or without
39  * modification, are permitted provided that the following conditions
40  * are met:
41  * 1. Redistributions of source code must retain the above copyright
42  *    notice, this list of conditions and the following disclaimer.
43  * 2. Redistributions in binary form must reproduce the above copyright
44  *    notice, this list of conditions and the following disclaimer in the
45  *    documentation and/or other materials provided with the distribution.
46  * 3. Neither the name of the University nor the names of its contributors
47  *    may be used to endorse or promote products derived from this software
48  *    without specific prior written permission.
49  *
50  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
51  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
52  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
53  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
54  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
55  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
56  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
57  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
58  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
59  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
60  * SUCH DAMAGE.
61  *
62  *	@(#)ip_input.c	8.2 (Berkeley) 1/4/94
63  */
64 
65 #include <sys/cdefs.h>
66 __FBSDID("$FreeBSD$");
67 
68 #include "opt_inet.h"
69 #include "opt_inet6.h"
70 #include "opt_ipsec.h"
71 #include "opt_route.h"
72 #include "opt_rss.h"
73 
74 #include <sys/param.h>
75 #include <sys/systm.h>
76 #include <sys/hhook.h>
77 #include <sys/malloc.h>
78 #include <sys/mbuf.h>
79 #include <sys/proc.h>
80 #include <sys/domain.h>
81 #include <sys/protosw.h>
82 #include <sys/sdt.h>
83 #include <sys/socket.h>
84 #include <sys/socketvar.h>
85 #include <sys/errno.h>
86 #include <sys/time.h>
87 #include <sys/kernel.h>
88 #include <sys/lock.h>
89 #include <sys/rmlock.h>
90 #include <sys/syslog.h>
91 #include <sys/sysctl.h>
92 
93 #include <net/if.h>
94 #include <net/if_var.h>
95 #include <net/if_types.h>
96 #include <net/if_dl.h>
97 #include <net/route.h>
98 #include <net/netisr.h>
99 #include <net/rss_config.h>
100 #include <net/pfil.h>
101 #include <net/vnet.h>
102 
103 #include <netinet/in.h>
104 #include <netinet/in_kdtrace.h>
105 #include <netinet/ip_var.h>
106 #include <netinet/in_systm.h>
107 #include <net/if_llatbl.h>
108 #ifdef INET
109 #include <netinet/ip.h>
110 #include <netinet/ip_icmp.h>
111 #endif /* INET */
112 #include <netinet/ip6.h>
113 #include <netinet6/in6_var.h>
114 #include <netinet6/ip6_var.h>
115 #include <netinet/in_pcb.h>
116 #include <netinet/icmp6.h>
117 #include <netinet6/scope6_var.h>
118 #include <netinet6/in6_ifattach.h>
119 #include <netinet6/mld6_var.h>
120 #include <netinet6/nd6.h>
121 #include <netinet6/in6_rss.h>
122 
123 #include <netipsec/ipsec_support.h>
124 
125 #include <netinet6/ip6protosw.h>
126 
127 extern struct domain inet6domain;
128 
129 u_char ip6_protox[IPPROTO_MAX];
130 VNET_DEFINE(struct in6_ifaddrhead, in6_ifaddrhead);
131 VNET_DEFINE(struct in6_ifaddrlisthead *, in6_ifaddrhashtbl);
132 VNET_DEFINE(u_long, in6_ifaddrhmask);
133 
134 static struct netisr_handler ip6_nh = {
135 	.nh_name = "ip6",
136 	.nh_handler = ip6_input,
137 	.nh_proto = NETISR_IPV6,
138 #ifdef RSS
139 	.nh_m2cpuid = rss_soft_m2cpuid_v6,
140 	.nh_policy = NETISR_POLICY_CPU,
141 	.nh_dispatch = NETISR_DISPATCH_HYBRID,
142 #else
143 	.nh_policy = NETISR_POLICY_FLOW,
144 #endif
145 };
146 
147 static int
148 sysctl_netinet6_intr_queue_maxlen(SYSCTL_HANDLER_ARGS)
149 {
150 	int error, qlimit;
151 
152 	netisr_getqlimit(&ip6_nh, &qlimit);
153 	error = sysctl_handle_int(oidp, &qlimit, 0, req);
154 	if (error || !req->newptr)
155 		return (error);
156 	if (qlimit < 1)
157 		return (EINVAL);
158 	return (netisr_setqlimit(&ip6_nh, qlimit));
159 }
160 SYSCTL_DECL(_net_inet6_ip6);
161 SYSCTL_PROC(_net_inet6_ip6, IPV6CTL_INTRQMAXLEN, intr_queue_maxlen,
162     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
163     0, 0, sysctl_netinet6_intr_queue_maxlen, "I",
164     "Maximum size of the IPv6 input queue");
165 
166 #ifdef RSS
167 static struct netisr_handler ip6_direct_nh = {
168 	.nh_name = "ip6_direct",
169 	.nh_handler = ip6_direct_input,
170 	.nh_proto = NETISR_IPV6_DIRECT,
171 	.nh_m2cpuid = rss_soft_m2cpuid_v6,
172 	.nh_policy = NETISR_POLICY_CPU,
173 	.nh_dispatch = NETISR_DISPATCH_HYBRID,
174 };
175 
176 static int
177 sysctl_netinet6_intr_direct_queue_maxlen(SYSCTL_HANDLER_ARGS)
178 {
179 	int error, qlimit;
180 
181 	netisr_getqlimit(&ip6_direct_nh, &qlimit);
182 	error = sysctl_handle_int(oidp, &qlimit, 0, req);
183 	if (error || !req->newptr)
184 		return (error);
185 	if (qlimit < 1)
186 		return (EINVAL);
187 	return (netisr_setqlimit(&ip6_direct_nh, qlimit));
188 }
189 SYSCTL_PROC(_net_inet6_ip6, IPV6CTL_INTRDQMAXLEN, intr_direct_queue_maxlen,
190     CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
191     0, 0, sysctl_netinet6_intr_direct_queue_maxlen, "I",
192     "Maximum size of the IPv6 direct input queue");
193 
194 #endif
195 
196 VNET_DEFINE(pfil_head_t, inet6_pfil_head);
197 
198 VNET_PCPUSTAT_DEFINE(struct ip6stat, ip6stat);
199 VNET_PCPUSTAT_SYSINIT(ip6stat);
200 #ifdef VIMAGE
201 VNET_PCPUSTAT_SYSUNINIT(ip6stat);
202 #endif /* VIMAGE */
203 
204 struct rmlock in6_ifaddr_lock;
205 RM_SYSINIT(in6_ifaddr_lock, &in6_ifaddr_lock, "in6_ifaddr_lock");
206 
207 static int ip6_hopopts_input(u_int32_t *, u_int32_t *, struct mbuf **, int *);
208 
209 /*
210  * IP6 initialization: fill in IP6 protocol switch table.
211  * All protocols not implemented in kernel go to raw IP6 protocol handler.
212  */
213 void
214 ip6_init(void)
215 {
216 	struct pfil_head_args args;
217 	struct protosw *pr;
218 	int i;
219 
220 	TUNABLE_INT_FETCH("net.inet6.ip6.auto_linklocal",
221 	    &V_ip6_auto_linklocal);
222 	TUNABLE_INT_FETCH("net.inet6.ip6.accept_rtadv", &V_ip6_accept_rtadv);
223 	TUNABLE_INT_FETCH("net.inet6.ip6.no_radr", &V_ip6_no_radr);
224 
225 	CK_STAILQ_INIT(&V_in6_ifaddrhead);
226 	V_in6_ifaddrhashtbl = hashinit(IN6ADDR_NHASH, M_IFADDR,
227 	    &V_in6_ifaddrhmask);
228 
229 	/* Initialize packet filter hooks. */
230 	args.pa_version = PFIL_VERSION;
231 	args.pa_flags = PFIL_IN | PFIL_OUT;
232 	args.pa_type = PFIL_TYPE_IP6;
233 	args.pa_headname = PFIL_INET6_NAME;
234 	V_inet6_pfil_head = pfil_head_register(&args);
235 
236 	if (hhook_head_register(HHOOK_TYPE_IPSEC_IN, AF_INET6,
237 	    &V_ipsec_hhh_in[HHOOK_IPSEC_INET6],
238 	    HHOOK_WAITOK | HHOOK_HEADISINVNET) != 0)
239 		printf("%s: WARNING: unable to register input helper hook\n",
240 		    __func__);
241 	if (hhook_head_register(HHOOK_TYPE_IPSEC_OUT, AF_INET6,
242 	    &V_ipsec_hhh_out[HHOOK_IPSEC_INET6],
243 	    HHOOK_WAITOK | HHOOK_HEADISINVNET) != 0)
244 		printf("%s: WARNING: unable to register output helper hook\n",
245 		    __func__);
246 
247 	scope6_init();
248 	addrsel_policy_init();
249 	nd6_init();
250 	frag6_init();
251 
252 	V_ip6_desync_factor = arc4random() % MAX_TEMP_DESYNC_FACTOR;
253 
254 	/* Skip global initialization stuff for non-default instances. */
255 #ifdef VIMAGE
256 	if (!IS_DEFAULT_VNET(curvnet)) {
257 		netisr_register_vnet(&ip6_nh);
258 #ifdef RSS
259 		netisr_register_vnet(&ip6_direct_nh);
260 #endif
261 		return;
262 	}
263 #endif
264 
265 	pr = pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW);
266 	if (pr == NULL)
267 		panic("ip6_init");
268 
269 	/* Initialize the entire ip6_protox[] array to IPPROTO_RAW. */
270 	for (i = 0; i < IPPROTO_MAX; i++)
271 		ip6_protox[i] = pr - inet6sw;
272 	/*
273 	 * Cycle through IP protocols and put them into the appropriate place
274 	 * in ip6_protox[].
275 	 */
276 	for (pr = inet6domain.dom_protosw;
277 	    pr < inet6domain.dom_protoswNPROTOSW; pr++)
278 		if (pr->pr_domain->dom_family == PF_INET6 &&
279 		    pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) {
280 			/* Be careful to only index valid IP protocols. */
281 			if (pr->pr_protocol < IPPROTO_MAX)
282 				ip6_protox[pr->pr_protocol] = pr - inet6sw;
283 		}
284 
285 	netisr_register(&ip6_nh);
286 #ifdef RSS
287 	netisr_register(&ip6_direct_nh);
288 #endif
289 }
290 
291 /*
292  * The protocol to be inserted into ip6_protox[] must be already registered
293  * in inet6sw[], either statically or through pf_proto_register().
294  */
295 int
296 ip6proto_register(short ip6proto)
297 {
298 	struct protosw *pr;
299 
300 	/* Sanity checks. */
301 	if (ip6proto <= 0 || ip6proto >= IPPROTO_MAX)
302 		return (EPROTONOSUPPORT);
303 
304 	/*
305 	 * The protocol slot must not be occupied by another protocol
306 	 * already.  An index pointing to IPPROTO_RAW is unused.
307 	 */
308 	pr = pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW);
309 	if (pr == NULL)
310 		return (EPFNOSUPPORT);
311 	if (ip6_protox[ip6proto] != pr - inet6sw)	/* IPPROTO_RAW */
312 		return (EEXIST);
313 
314 	/*
315 	 * Find the protocol position in inet6sw[] and set the index.
316 	 */
317 	for (pr = inet6domain.dom_protosw;
318 	    pr < inet6domain.dom_protoswNPROTOSW; pr++) {
319 		if (pr->pr_domain->dom_family == PF_INET6 &&
320 		    pr->pr_protocol && pr->pr_protocol == ip6proto) {
321 			ip6_protox[pr->pr_protocol] = pr - inet6sw;
322 			return (0);
323 		}
324 	}
325 	return (EPROTONOSUPPORT);
326 }
327 
328 int
329 ip6proto_unregister(short ip6proto)
330 {
331 	struct protosw *pr;
332 
333 	/* Sanity checks. */
334 	if (ip6proto <= 0 || ip6proto >= IPPROTO_MAX)
335 		return (EPROTONOSUPPORT);
336 
337 	/* Check if the protocol was indeed registered. */
338 	pr = pffindproto(PF_INET6, IPPROTO_RAW, SOCK_RAW);
339 	if (pr == NULL)
340 		return (EPFNOSUPPORT);
341 	if (ip6_protox[ip6proto] == pr - inet6sw)	/* IPPROTO_RAW */
342 		return (ENOENT);
343 
344 	/* Reset the protocol slot to IPPROTO_RAW. */
345 	ip6_protox[ip6proto] = pr - inet6sw;
346 	return (0);
347 }
348 
349 #ifdef VIMAGE
350 static void
351 ip6_destroy(void *unused __unused)
352 {
353 	struct ifaddr *ifa, *nifa;
354 	struct ifnet *ifp;
355 	int error;
356 
357 #ifdef RSS
358 	netisr_unregister_vnet(&ip6_direct_nh);
359 #endif
360 	netisr_unregister_vnet(&ip6_nh);
361 
362 	pfil_head_unregister(V_inet6_pfil_head);
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 	CK_STAILQ_FOREACH(ifp, &V_ifnet, if_link) {
379 		/* Cannot lock here - lock recursion. */
380 		/* IF_ADDR_LOCK(ifp); */
381 		CK_STAILQ_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 	frag6_destroy();
396 	nd6_destroy();
397 	in6_ifattach_destroy();
398 
399 	hashdestroy(V_in6_ifaddrhashtbl, M_IFADDR, V_in6_ifaddrhmask);
400 }
401 
402 VNET_SYSUNINIT(inet6, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, ip6_destroy, NULL);
403 #endif
404 
405 static int
406 ip6_input_hbh(struct mbuf **mp, uint32_t *plen, uint32_t *rtalert, int *off,
407     int *nxt, int *ours)
408 {
409 	struct mbuf *m;
410 	struct ip6_hdr *ip6;
411 	struct ip6_hbh *hbh;
412 
413 	if (ip6_hopopts_input(plen, rtalert, mp, off)) {
414 #if 0	/*touches NULL pointer*/
415 		in6_ifstat_inc((*mp)->m_pkthdr.rcvif, ifs6_in_discard);
416 #endif
417 		goto out;	/* m have already been freed */
418 	}
419 
420 	/* adjust pointer */
421 	m = *mp;
422 	ip6 = mtod(m, struct ip6_hdr *);
423 
424 	/*
425 	 * if the payload length field is 0 and the next header field
426 	 * indicates Hop-by-Hop Options header, then a Jumbo Payload
427 	 * option MUST be included.
428 	 */
429 	if (ip6->ip6_plen == 0 && *plen == 0) {
430 		/*
431 		 * Note that if a valid jumbo payload option is
432 		 * contained, ip6_hopopts_input() must set a valid
433 		 * (non-zero) payload length to the variable plen.
434 		 */
435 		IP6STAT_INC(ip6s_badoptions);
436 		in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard);
437 		in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_hdrerr);
438 		icmp6_error(m, ICMP6_PARAM_PROB,
439 			    ICMP6_PARAMPROB_HEADER,
440 			    (caddr_t)&ip6->ip6_plen - (caddr_t)ip6);
441 		goto out;
442 	}
443 	/* ip6_hopopts_input() ensures that mbuf is contiguous */
444 	hbh = (struct ip6_hbh *)(ip6 + 1);
445 	*nxt = hbh->ip6h_nxt;
446 
447 	/*
448 	 * If we are acting as a router and the packet contains a
449 	 * router alert option, see if we know the option value.
450 	 * Currently, we only support the option value for MLD, in which
451 	 * case we should pass the packet to the multicast routing
452 	 * daemon.
453 	 */
454 	if (*rtalert != ~0) {
455 		switch (*rtalert) {
456 		case IP6OPT_RTALERT_MLD:
457 			if (V_ip6_forwarding)
458 				*ours = 1;
459 			break;
460 		default:
461 			/*
462 			 * RFC2711 requires unrecognized values must be
463 			 * silently ignored.
464 			 */
465 			break;
466 		}
467 	}
468 
469 	return (0);
470 
471 out:
472 	return (1);
473 }
474 
475 #ifdef RSS
476 /*
477  * IPv6 direct input routine.
478  *
479  * This is called when reinjecting completed fragments where
480  * all of the previous checking and book-keeping has been done.
481  */
482 void
483 ip6_direct_input(struct mbuf *m)
484 {
485 	int off, nxt;
486 	int nest;
487 	struct m_tag *mtag;
488 	struct ip6_direct_ctx *ip6dc;
489 
490 	mtag = m_tag_locate(m, MTAG_ABI_IPV6, IPV6_TAG_DIRECT, NULL);
491 	KASSERT(mtag != NULL, ("Reinjected packet w/o direct ctx tag!"));
492 
493 	ip6dc = (struct ip6_direct_ctx *)(mtag + 1);
494 	nxt = ip6dc->ip6dc_nxt;
495 	off = ip6dc->ip6dc_off;
496 
497 	nest = 0;
498 
499 	m_tag_delete(m, mtag);
500 
501 	while (nxt != IPPROTO_DONE) {
502 		if (V_ip6_hdrnestlimit && (++nest > V_ip6_hdrnestlimit)) {
503 			IP6STAT_INC(ip6s_toomanyhdr);
504 			goto bad;
505 		}
506 
507 		/*
508 		 * protection against faulty packet - there should be
509 		 * more sanity checks in header chain processing.
510 		 */
511 		if (m->m_pkthdr.len < off) {
512 			IP6STAT_INC(ip6s_tooshort);
513 			in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated);
514 			goto bad;
515 		}
516 
517 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
518 		if (IPSEC_ENABLED(ipv6)) {
519 			if (IPSEC_INPUT(ipv6, m, off, nxt) != 0)
520 				return;
521 		}
522 #endif /* IPSEC */
523 
524 		nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &off, nxt);
525 	}
526 	return;
527 bad:
528 	m_freem(m);
529 }
530 #endif
531 
532 void
533 ip6_input(struct mbuf *m)
534 {
535 	struct in6_addr odst;
536 	struct ip6_hdr *ip6;
537 	struct in6_ifaddr *ia;
538 	struct ifnet *rcvif;
539 	u_int32_t plen;
540 	u_int32_t rtalert = ~0;
541 	int off = sizeof(struct ip6_hdr), nest;
542 	int nxt, ours = 0;
543 	int srcrt = 0;
544 
545 	/*
546 	 * Drop the packet if IPv6 operation is disabled on the interface.
547 	 */
548 	rcvif = m->m_pkthdr.rcvif;
549 	if ((ND_IFINFO(rcvif)->flags & ND6_IFF_IFDISABLED))
550 		goto bad;
551 
552 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
553 	/*
554 	 * should the inner packet be considered authentic?
555 	 * see comment in ah4_input().
556 	 * NB: m cannot be NULL when passed to the input routine
557 	 */
558 
559 	m->m_flags &= ~M_AUTHIPHDR;
560 	m->m_flags &= ~M_AUTHIPDGM;
561 
562 #endif /* IPSEC */
563 
564 	if (m->m_flags & M_FASTFWD_OURS) {
565 		/*
566 		 * Firewall changed destination to local.
567 		 */
568 		ip6 = mtod(m, struct ip6_hdr *);
569 		goto passin;
570 	}
571 
572 	/*
573 	 * mbuf statistics
574 	 */
575 	if (m->m_flags & M_EXT) {
576 		if (m->m_next)
577 			IP6STAT_INC(ip6s_mext2m);
578 		else
579 			IP6STAT_INC(ip6s_mext1);
580 	} else {
581 		if (m->m_next) {
582 			if (m->m_flags & M_LOOP) {
583 				IP6STAT_INC(ip6s_m2m[V_loif->if_index]);
584 			} else if (rcvif->if_index < IP6S_M2MMAX)
585 				IP6STAT_INC(ip6s_m2m[rcvif->if_index]);
586 			else
587 				IP6STAT_INC(ip6s_m2m[0]);
588 		} else
589 			IP6STAT_INC(ip6s_m1);
590 	}
591 
592 	in6_ifstat_inc(rcvif, ifs6_in_receive);
593 	IP6STAT_INC(ip6s_total);
594 
595 	/*
596 	 * L2 bridge code and some other code can return mbuf chain
597 	 * that does not conform to KAME requirement.  too bad.
598 	 * XXX: fails to join if interface MTU > MCLBYTES.  jumbogram?
599 	 */
600 	if (m && m->m_next != NULL && m->m_pkthdr.len < MCLBYTES) {
601 		struct mbuf *n;
602 
603 		if (m->m_pkthdr.len > MHLEN)
604 			n = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
605 		else
606 			n = m_gethdr(M_NOWAIT, MT_DATA);
607 		if (n == NULL)
608 			goto bad;
609 
610 		m_move_pkthdr(n, m);
611 		m_copydata(m, 0, n->m_pkthdr.len, mtod(n, caddr_t));
612 		n->m_len = n->m_pkthdr.len;
613 		m_freem(m);
614 		m = n;
615 	}
616 	if (m->m_len < sizeof(struct ip6_hdr)) {
617 		if ((m = m_pullup(m, sizeof(struct ip6_hdr))) == NULL) {
618 			IP6STAT_INC(ip6s_toosmall);
619 			in6_ifstat_inc(rcvif, ifs6_in_hdrerr);
620 			goto bad;
621 		}
622 	}
623 
624 	ip6 = mtod(m, struct ip6_hdr *);
625 	if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
626 		IP6STAT_INC(ip6s_badvers);
627 		in6_ifstat_inc(rcvif, ifs6_in_hdrerr);
628 		goto bad;
629 	}
630 
631 	IP6STAT_INC(ip6s_nxthist[ip6->ip6_nxt]);
632 	IP_PROBE(receive, NULL, NULL, ip6, rcvif, NULL, ip6);
633 
634 	/*
635 	 * Check against address spoofing/corruption.
636 	 */
637 	if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src) ||
638 	    IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst)) {
639 		/*
640 		 * XXX: "badscope" is not very suitable for a multicast source.
641 		 */
642 		IP6STAT_INC(ip6s_badscope);
643 		in6_ifstat_inc(rcvif, ifs6_in_addrerr);
644 		goto bad;
645 	}
646 	if (IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst) &&
647 	    !(m->m_flags & M_LOOP)) {
648 		/*
649 		 * In this case, the packet should come from the loopback
650 		 * interface.  However, we cannot just check the if_flags,
651 		 * because ip6_mloopback() passes the "actual" interface
652 		 * as the outgoing/incoming interface.
653 		 */
654 		IP6STAT_INC(ip6s_badscope);
655 		in6_ifstat_inc(rcvif, ifs6_in_addrerr);
656 		goto bad;
657 	}
658 	if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) &&
659 	    IPV6_ADDR_MC_SCOPE(&ip6->ip6_dst) == 0) {
660 		/*
661 		 * RFC4291 2.7:
662 		 * Nodes must not originate a packet to a multicast address
663 		 * whose scop field contains the reserved value 0; if such
664 		 * a packet is received, it must be silently dropped.
665 		 */
666 		IP6STAT_INC(ip6s_badscope);
667 		in6_ifstat_inc(rcvif, ifs6_in_addrerr);
668 		goto bad;
669 	}
670 #ifdef ALTQ
671 	if (altq_input != NULL && (*altq_input)(m, AF_INET6) == 0) {
672 		/* packet is dropped by traffic conditioner */
673 		return;
674 	}
675 #endif
676 	/*
677 	 * The following check is not documented in specs.  A malicious
678 	 * party may be able to use IPv4 mapped addr to confuse tcp/udp stack
679 	 * and bypass security checks (act as if it was from 127.0.0.1 by using
680 	 * IPv6 src ::ffff:127.0.0.1).  Be cautious.
681 	 *
682 	 * We have supported IPv6-only kernels for a few years and this issue
683 	 * has not come up.  The world seems to move mostly towards not using
684 	 * v4mapped on the wire, so it makes sense for us to keep rejecting
685 	 * any such packets.
686 	 */
687 	if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) ||
688 	    IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) {
689 		IP6STAT_INC(ip6s_badscope);
690 		in6_ifstat_inc(rcvif, ifs6_in_addrerr);
691 		goto bad;
692 	}
693 #if 0
694 	/*
695 	 * Reject packets with IPv4 compatible addresses (auto tunnel).
696 	 *
697 	 * The code forbids auto tunnel relay case in RFC1933 (the check is
698 	 * stronger than RFC1933).  We may want to re-enable it if mech-xx
699 	 * is revised to forbid relaying case.
700 	 */
701 	if (IN6_IS_ADDR_V4COMPAT(&ip6->ip6_src) ||
702 	    IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) {
703 		IP6STAT_INC(ip6s_badscope);
704 		in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_addrerr);
705 		goto bad;
706 	}
707 #endif
708 	/*
709 	 * Try to forward the packet, but if we fail continue.
710 	 * ip6_tryforward() does not generate redirects, so fall
711 	 * through to normal processing if redirects are required.
712 	 * ip6_tryforward() does inbound and outbound packet firewall
713 	 * processing. If firewall has decided that destination becomes
714 	 * our local address, it sets M_FASTFWD_OURS flag. In this
715 	 * case skip another inbound firewall processing and update
716 	 * ip6 pointer.
717 	 */
718 	if (V_ip6_forwarding != 0 && V_ip6_sendredirects == 0
719 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
720 	    && (!IPSEC_ENABLED(ipv6) ||
721 	    IPSEC_CAPS(ipv6, m, IPSEC_CAP_OPERABLE) == 0)
722 #endif
723 	    ) {
724 		if ((m = ip6_tryforward(m)) == NULL)
725 			return;
726 		if (m->m_flags & M_FASTFWD_OURS) {
727 			ip6 = mtod(m, struct ip6_hdr *);
728 			goto passin;
729 		}
730 	}
731 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
732 	/*
733 	 * Bypass packet filtering for packets previously handled by IPsec.
734 	 */
735 	if (IPSEC_ENABLED(ipv6) &&
736 	    IPSEC_CAPS(ipv6, m, IPSEC_CAP_BYPASS_FILTER) != 0)
737 			goto passin;
738 #endif
739 	/*
740 	 * Run through list of hooks for input packets.
741 	 *
742 	 * NB: Beware of the destination address changing
743 	 *     (e.g. by NAT rewriting).  When this happens,
744 	 *     tell ip6_forward to do the right thing.
745 	 */
746 
747 	/* Jump over all PFIL processing if hooks are not active. */
748 	if (!PFIL_HOOKED_IN(V_inet6_pfil_head))
749 		goto passin;
750 
751 	odst = ip6->ip6_dst;
752 	if (pfil_run_hooks(V_inet6_pfil_head, &m, m->m_pkthdr.rcvif, PFIL_IN,
753 	    NULL) != PFIL_PASS)
754 		return;
755 	ip6 = mtod(m, struct ip6_hdr *);
756 	srcrt = !IN6_ARE_ADDR_EQUAL(&odst, &ip6->ip6_dst);
757 	if ((m->m_flags & (M_IP6_NEXTHOP | M_FASTFWD_OURS)) == M_IP6_NEXTHOP &&
758 	    m_tag_find(m, PACKET_TAG_IPFORWARD, NULL) != NULL) {
759 		/*
760 		 * Directly ship the packet on.  This allows forwarding
761 		 * packets originally destined to us to some other directly
762 		 * connected host.
763 		 */
764 		ip6_forward(m, 1);
765 		return;
766 	}
767 
768 passin:
769 	/*
770 	 * Disambiguate address scope zones (if there is ambiguity).
771 	 * We first make sure that the original source or destination address
772 	 * is not in our internal form for scoped addresses.  Such addresses
773 	 * are not necessarily invalid spec-wise, but we cannot accept them due
774 	 * to the usage conflict.
775 	 * in6_setscope() then also checks and rejects the cases where src or
776 	 * dst are the loopback address and the receiving interface
777 	 * is not loopback.
778 	 */
779 	if (in6_clearscope(&ip6->ip6_src) || in6_clearscope(&ip6->ip6_dst)) {
780 		IP6STAT_INC(ip6s_badscope); /* XXX */
781 		goto bad;
782 	}
783 	if (in6_setscope(&ip6->ip6_src, rcvif, NULL) ||
784 	    in6_setscope(&ip6->ip6_dst, rcvif, NULL)) {
785 		IP6STAT_INC(ip6s_badscope);
786 		goto bad;
787 	}
788 	if (m->m_flags & M_FASTFWD_OURS) {
789 		m->m_flags &= ~M_FASTFWD_OURS;
790 		ours = 1;
791 		goto hbhcheck;
792 	}
793 	/*
794 	 * Multicast check. Assume packet is for us to avoid
795 	 * prematurely taking locks.
796 	 */
797 	if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
798 		ours = 1;
799 		in6_ifstat_inc(rcvif, ifs6_in_mcast);
800 		goto hbhcheck;
801 	}
802 	/*
803 	 * Unicast check
804 	 * XXX: For now we keep link-local IPv6 addresses with embedded
805 	 *      scope zone id, therefore we use zero zoneid here.
806 	 */
807 	ia = in6ifa_ifwithaddr(&ip6->ip6_dst, 0 /* XXX */);
808 	if (ia != NULL) {
809 		if (ia->ia6_flags & IN6_IFF_NOTREADY) {
810 			char ip6bufs[INET6_ADDRSTRLEN];
811 			char ip6bufd[INET6_ADDRSTRLEN];
812 			/* address is not ready, so discard the packet. */
813 			nd6log((LOG_INFO,
814 			    "ip6_input: packet to an unready address %s->%s\n",
815 			    ip6_sprintf(ip6bufs, &ip6->ip6_src),
816 			    ip6_sprintf(ip6bufd, &ip6->ip6_dst)));
817 			ifa_free(&ia->ia_ifa);
818 			goto bad;
819 		}
820 		/* Count the packet in the ip address stats */
821 		counter_u64_add(ia->ia_ifa.ifa_ipackets, 1);
822 		counter_u64_add(ia->ia_ifa.ifa_ibytes, m->m_pkthdr.len);
823 		ifa_free(&ia->ia_ifa);
824 		ours = 1;
825 		goto hbhcheck;
826 	}
827 
828 	/*
829 	 * Now there is no reason to process the packet if it's not our own
830 	 * and we're not a router.
831 	 */
832 	if (!V_ip6_forwarding) {
833 		IP6STAT_INC(ip6s_cantforward);
834 		goto bad;
835 	}
836 
837   hbhcheck:
838 	/*
839 	 * Process Hop-by-Hop options header if it's contained.
840 	 * m may be modified in ip6_hopopts_input().
841 	 * If a JumboPayload option is included, plen will also be modified.
842 	 */
843 	plen = (u_int32_t)ntohs(ip6->ip6_plen);
844 	if (ip6->ip6_nxt == IPPROTO_HOPOPTS) {
845 		if (ip6_input_hbh(&m, &plen, &rtalert, &off, &nxt, &ours) != 0)
846 			return;
847 	} else
848 		nxt = ip6->ip6_nxt;
849 
850 	/*
851 	 * Use mbuf flags to propagate Router Alert option to
852 	 * ICMPv6 layer, as hop-by-hop options have been stripped.
853 	 */
854 	if (rtalert != ~0)
855 		m->m_flags |= M_RTALERT_MLD;
856 
857 	/*
858 	 * Check that the amount of data in the buffers
859 	 * is as at least much as the IPv6 header would have us expect.
860 	 * Trim mbufs if longer than we expect.
861 	 * Drop packet if shorter than we expect.
862 	 */
863 	if (m->m_pkthdr.len - sizeof(struct ip6_hdr) < plen) {
864 		IP6STAT_INC(ip6s_tooshort);
865 		in6_ifstat_inc(rcvif, ifs6_in_truncated);
866 		goto bad;
867 	}
868 	if (m->m_pkthdr.len > sizeof(struct ip6_hdr) + plen) {
869 		if (m->m_len == m->m_pkthdr.len) {
870 			m->m_len = sizeof(struct ip6_hdr) + plen;
871 			m->m_pkthdr.len = sizeof(struct ip6_hdr) + plen;
872 		} else
873 			m_adj(m, sizeof(struct ip6_hdr) + plen - m->m_pkthdr.len);
874 	}
875 
876 	/*
877 	 * Forward if desirable.
878 	 */
879 	if (V_ip6_mrouter &&
880 	    IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
881 		/*
882 		 * If we are acting as a multicast router, all
883 		 * incoming multicast packets are passed to the
884 		 * kernel-level multicast forwarding function.
885 		 * The packet is returned (relatively) intact; if
886 		 * ip6_mforward() returns a non-zero value, the packet
887 		 * must be discarded, else it may be accepted below.
888 		 *
889 		 * XXX TODO: Check hlim and multicast scope here to avoid
890 		 * unnecessarily calling into ip6_mforward().
891 		 */
892 		if (ip6_mforward && ip6_mforward(ip6, rcvif, m)) {
893 			IP6STAT_INC(ip6s_cantforward);
894 			goto bad;
895 		}
896 	} else if (!ours) {
897 		ip6_forward(m, srcrt);
898 		return;
899 	}
900 
901 	/*
902 	 * Tell launch routine the next header
903 	 */
904 	IP6STAT_INC(ip6s_delivered);
905 	in6_ifstat_inc(rcvif, ifs6_in_deliver);
906 	nest = 0;
907 
908 	while (nxt != IPPROTO_DONE) {
909 		if (V_ip6_hdrnestlimit && (++nest > V_ip6_hdrnestlimit)) {
910 			IP6STAT_INC(ip6s_toomanyhdr);
911 			goto bad;
912 		}
913 
914 		/*
915 		 * protection against faulty packet - there should be
916 		 * more sanity checks in header chain processing.
917 		 */
918 		if (m->m_pkthdr.len < off) {
919 			IP6STAT_INC(ip6s_tooshort);
920 			in6_ifstat_inc(rcvif, ifs6_in_truncated);
921 			goto bad;
922 		}
923 
924 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
925 		if (IPSEC_ENABLED(ipv6)) {
926 			if (IPSEC_INPUT(ipv6, m, off, nxt) != 0)
927 				return;
928 		}
929 #endif /* IPSEC */
930 
931 		nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &off, nxt);
932 	}
933 	return;
934 bad:
935 	in6_ifstat_inc(rcvif, ifs6_in_discard);
936 	if (m != NULL)
937 		m_freem(m);
938 }
939 
940 /*
941  * Hop-by-Hop options header processing. If a valid jumbo payload option is
942  * included, the real payload length will be stored in plenp.
943  *
944  * rtalertp - XXX: should be stored more smart way
945  */
946 static int
947 ip6_hopopts_input(u_int32_t *plenp, u_int32_t *rtalertp,
948     struct mbuf **mp, int *offp)
949 {
950 	struct mbuf *m = *mp;
951 	int off = *offp, hbhlen;
952 	struct ip6_hbh *hbh;
953 
954 	/* validation of the length of the header */
955 	if (m->m_len < off + sizeof(*hbh)) {
956 		m = m_pullup(m, off + sizeof(*hbh));
957 		if (m == NULL) {
958 			IP6STAT_INC(ip6s_exthdrtoolong);
959 			*mp = NULL;
960 			return (-1);
961 		}
962 	}
963 	hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off);
964 	hbhlen = (hbh->ip6h_len + 1) << 3;
965 
966 	if (m->m_len < off + hbhlen) {
967 		m = m_pullup(m, off + hbhlen);
968 		if (m == NULL) {
969 			IP6STAT_INC(ip6s_exthdrtoolong);
970 			*mp = NULL;
971 			return (-1);
972 		}
973 	}
974 	hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off);
975 	off += hbhlen;
976 	hbhlen -= sizeof(struct ip6_hbh);
977 	if (ip6_process_hopopts(m, (u_int8_t *)hbh + sizeof(struct ip6_hbh),
978 				hbhlen, rtalertp, plenp) < 0) {
979 		*mp = NULL;
980 		return (-1);
981 	}
982 
983 	*offp = off;
984 	*mp = m;
985 	return (0);
986 }
987 
988 /*
989  * Search header for all Hop-by-hop options and process each option.
990  * This function is separate from ip6_hopopts_input() in order to
991  * handle a case where the sending node itself process its hop-by-hop
992  * options header. In such a case, the function is called from ip6_output().
993  *
994  * The function assumes that hbh header is located right after the IPv6 header
995  * (RFC2460 p7), opthead is pointer into data content in m, and opthead to
996  * opthead + hbhlen is located in contiguous memory region.
997  */
998 int
999 ip6_process_hopopts(struct mbuf *m, u_int8_t *opthead, int hbhlen,
1000     u_int32_t *rtalertp, u_int32_t *plenp)
1001 {
1002 	struct ip6_hdr *ip6;
1003 	int optlen = 0;
1004 	u_int8_t *opt = opthead;
1005 	u_int16_t rtalert_val;
1006 	u_int32_t jumboplen;
1007 	const int erroff = sizeof(struct ip6_hdr) + sizeof(struct ip6_hbh);
1008 
1009 	for (; hbhlen > 0; hbhlen -= optlen, opt += optlen) {
1010 		switch (*opt) {
1011 		case IP6OPT_PAD1:
1012 			optlen = 1;
1013 			break;
1014 		case IP6OPT_PADN:
1015 			if (hbhlen < IP6OPT_MINLEN) {
1016 				IP6STAT_INC(ip6s_toosmall);
1017 				goto bad;
1018 			}
1019 			optlen = *(opt + 1) + 2;
1020 			break;
1021 		case IP6OPT_ROUTER_ALERT:
1022 			/* XXX may need check for alignment */
1023 			if (hbhlen < IP6OPT_RTALERT_LEN) {
1024 				IP6STAT_INC(ip6s_toosmall);
1025 				goto bad;
1026 			}
1027 			if (*(opt + 1) != IP6OPT_RTALERT_LEN - 2) {
1028 				/* XXX stat */
1029 				icmp6_error(m, ICMP6_PARAM_PROB,
1030 				    ICMP6_PARAMPROB_HEADER,
1031 				    erroff + opt + 1 - opthead);
1032 				return (-1);
1033 			}
1034 			optlen = IP6OPT_RTALERT_LEN;
1035 			bcopy((caddr_t)(opt + 2), (caddr_t)&rtalert_val, 2);
1036 			*rtalertp = ntohs(rtalert_val);
1037 			break;
1038 		case IP6OPT_JUMBO:
1039 			/* XXX may need check for alignment */
1040 			if (hbhlen < IP6OPT_JUMBO_LEN) {
1041 				IP6STAT_INC(ip6s_toosmall);
1042 				goto bad;
1043 			}
1044 			if (*(opt + 1) != IP6OPT_JUMBO_LEN - 2) {
1045 				/* XXX stat */
1046 				icmp6_error(m, ICMP6_PARAM_PROB,
1047 				    ICMP6_PARAMPROB_HEADER,
1048 				    erroff + opt + 1 - opthead);
1049 				return (-1);
1050 			}
1051 			optlen = IP6OPT_JUMBO_LEN;
1052 
1053 			/*
1054 			 * IPv6 packets that have non 0 payload length
1055 			 * must not contain a jumbo payload option.
1056 			 */
1057 			ip6 = mtod(m, struct ip6_hdr *);
1058 			if (ip6->ip6_plen) {
1059 				IP6STAT_INC(ip6s_badoptions);
1060 				icmp6_error(m, ICMP6_PARAM_PROB,
1061 				    ICMP6_PARAMPROB_HEADER,
1062 				    erroff + opt - opthead);
1063 				return (-1);
1064 			}
1065 
1066 			/*
1067 			 * We may see jumbolen in unaligned location, so
1068 			 * we'd need to perform bcopy().
1069 			 */
1070 			bcopy(opt + 2, &jumboplen, sizeof(jumboplen));
1071 			jumboplen = (u_int32_t)htonl(jumboplen);
1072 
1073 #if 1
1074 			/*
1075 			 * if there are multiple jumbo payload options,
1076 			 * *plenp will be non-zero and the packet will be
1077 			 * rejected.
1078 			 * the behavior may need some debate in ipngwg -
1079 			 * multiple options does not make sense, however,
1080 			 * there's no explicit mention in specification.
1081 			 */
1082 			if (*plenp != 0) {
1083 				IP6STAT_INC(ip6s_badoptions);
1084 				icmp6_error(m, ICMP6_PARAM_PROB,
1085 				    ICMP6_PARAMPROB_HEADER,
1086 				    erroff + opt + 2 - opthead);
1087 				return (-1);
1088 			}
1089 #endif
1090 
1091 			/*
1092 			 * jumbo payload length must be larger than 65535.
1093 			 */
1094 			if (jumboplen <= IPV6_MAXPACKET) {
1095 				IP6STAT_INC(ip6s_badoptions);
1096 				icmp6_error(m, ICMP6_PARAM_PROB,
1097 				    ICMP6_PARAMPROB_HEADER,
1098 				    erroff + opt + 2 - opthead);
1099 				return (-1);
1100 			}
1101 			*plenp = jumboplen;
1102 
1103 			break;
1104 		default:		/* unknown option */
1105 			if (hbhlen < IP6OPT_MINLEN) {
1106 				IP6STAT_INC(ip6s_toosmall);
1107 				goto bad;
1108 			}
1109 			optlen = ip6_unknown_opt(opt, m,
1110 			    erroff + opt - opthead);
1111 			if (optlen == -1)
1112 				return (-1);
1113 			optlen += 2;
1114 			break;
1115 		}
1116 	}
1117 
1118 	return (0);
1119 
1120   bad:
1121 	m_freem(m);
1122 	return (-1);
1123 }
1124 
1125 /*
1126  * Unknown option processing.
1127  * The third argument `off' is the offset from the IPv6 header to the option,
1128  * which is necessary if the IPv6 header the and option header and IPv6 header
1129  * is not contiguous in order to return an ICMPv6 error.
1130  */
1131 int
1132 ip6_unknown_opt(u_int8_t *optp, struct mbuf *m, int off)
1133 {
1134 	struct ip6_hdr *ip6;
1135 
1136 	switch (IP6OPT_TYPE(*optp)) {
1137 	case IP6OPT_TYPE_SKIP: /* ignore the option */
1138 		return ((int)*(optp + 1));
1139 	case IP6OPT_TYPE_DISCARD:	/* silently discard */
1140 		m_freem(m);
1141 		return (-1);
1142 	case IP6OPT_TYPE_FORCEICMP: /* send ICMP even if multicasted */
1143 		IP6STAT_INC(ip6s_badoptions);
1144 		icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, off);
1145 		return (-1);
1146 	case IP6OPT_TYPE_ICMP: /* send ICMP if not multicasted */
1147 		IP6STAT_INC(ip6s_badoptions);
1148 		ip6 = mtod(m, struct ip6_hdr *);
1149 		if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) ||
1150 		    (m->m_flags & (M_BCAST|M_MCAST)))
1151 			m_freem(m);
1152 		else
1153 			icmp6_error(m, ICMP6_PARAM_PROB,
1154 				    ICMP6_PARAMPROB_OPTION, off);
1155 		return (-1);
1156 	}
1157 
1158 	m_freem(m);		/* XXX: NOTREACHED */
1159 	return (-1);
1160 }
1161 
1162 /*
1163  * Create the "control" list for this pcb.
1164  * These functions will not modify mbuf chain at all.
1165  *
1166  * The routine will be called from upper layer handlers like tcp6_input().
1167  * Thus the routine assumes that the caller (tcp6_input) have already
1168  * called m_pullup() and all the extension headers are located in the
1169  * very first mbuf on the mbuf chain.
1170  *
1171  * ip6_savecontrol_v4 will handle those options that are possible to be
1172  * set on a v4-mapped socket.
1173  * ip6_savecontrol will directly call ip6_savecontrol_v4 to handle those
1174  * options and handle the v6-only ones itself.
1175  */
1176 struct mbuf **
1177 ip6_savecontrol_v4(struct inpcb *inp, struct mbuf *m, struct mbuf **mp,
1178     int *v4only)
1179 {
1180 	struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1181 
1182 #ifdef SO_TIMESTAMP
1183 	if ((inp->inp_socket->so_options & SO_TIMESTAMP) != 0) {
1184 		union {
1185 			struct timeval tv;
1186 			struct bintime bt;
1187 			struct timespec ts;
1188 		} t;
1189 		struct bintime boottimebin, bt1;
1190 		struct timespec ts1;
1191 		bool stamped;
1192 
1193 		stamped = false;
1194 		switch (inp->inp_socket->so_ts_clock) {
1195 		case SO_TS_REALTIME_MICRO:
1196 			if ((m->m_flags & (M_PKTHDR | M_TSTMP)) == (M_PKTHDR |
1197 			    M_TSTMP)) {
1198 				mbuf_tstmp2timespec(m, &ts1);
1199 				timespec2bintime(&ts1, &bt1);
1200 				getboottimebin(&boottimebin);
1201 				bintime_add(&bt1, &boottimebin);
1202 				bintime2timeval(&bt1, &t.tv);
1203 			} else {
1204 				microtime(&t.tv);
1205 			}
1206 			*mp = sbcreatecontrol((caddr_t) &t.tv, sizeof(t.tv),
1207 			    SCM_TIMESTAMP, SOL_SOCKET);
1208 			if (*mp != NULL) {
1209 				mp = &(*mp)->m_next;
1210 				stamped = true;
1211 			}
1212 			break;
1213 
1214 		case SO_TS_BINTIME:
1215 			if ((m->m_flags & (M_PKTHDR | M_TSTMP)) == (M_PKTHDR |
1216 			    M_TSTMP)) {
1217 				mbuf_tstmp2timespec(m, &ts1);
1218 				timespec2bintime(&ts1, &t.bt);
1219 				getboottimebin(&boottimebin);
1220 				bintime_add(&t.bt, &boottimebin);
1221 			} else {
1222 				bintime(&t.bt);
1223 			}
1224 			*mp = sbcreatecontrol((caddr_t)&t.bt, sizeof(t.bt),
1225 			    SCM_BINTIME, SOL_SOCKET);
1226 			if (*mp != NULL) {
1227 				mp = &(*mp)->m_next;
1228 				stamped = true;
1229 			}
1230 			break;
1231 
1232 		case SO_TS_REALTIME:
1233 			if ((m->m_flags & (M_PKTHDR | M_TSTMP)) == (M_PKTHDR |
1234 			    M_TSTMP)) {
1235 				mbuf_tstmp2timespec(m, &t.ts);
1236 				getboottimebin(&boottimebin);
1237 				bintime2timespec(&boottimebin, &ts1);
1238 				timespecadd(&t.ts, &ts1, &t.ts);
1239 			} else {
1240 				nanotime(&t.ts);
1241 			}
1242 			*mp = sbcreatecontrol((caddr_t)&t.ts, sizeof(t.ts),
1243 			    SCM_REALTIME, SOL_SOCKET);
1244 			if (*mp != NULL) {
1245 				mp = &(*mp)->m_next;
1246 				stamped = true;
1247 			}
1248 			break;
1249 
1250 		case SO_TS_MONOTONIC:
1251 			if ((m->m_flags & (M_PKTHDR | M_TSTMP)) == (M_PKTHDR |
1252 			    M_TSTMP))
1253 				mbuf_tstmp2timespec(m, &t.ts);
1254 			else
1255 				nanouptime(&t.ts);
1256 			*mp = sbcreatecontrol((caddr_t)&t.ts, sizeof(t.ts),
1257 			    SCM_MONOTONIC, SOL_SOCKET);
1258 			if (*mp != NULL) {
1259 				mp = &(*mp)->m_next;
1260 				stamped = true;
1261 			}
1262 			break;
1263 
1264 		default:
1265 			panic("unknown (corrupted) so_ts_clock");
1266 		}
1267 		if (stamped && (m->m_flags & (M_PKTHDR | M_TSTMP)) ==
1268 		    (M_PKTHDR | M_TSTMP)) {
1269 			struct sock_timestamp_info sti;
1270 
1271 			bzero(&sti, sizeof(sti));
1272 			sti.st_info_flags = ST_INFO_HW;
1273 			if ((m->m_flags & M_TSTMP_HPREC) != 0)
1274 				sti.st_info_flags |= ST_INFO_HW_HPREC;
1275 			*mp = sbcreatecontrol((caddr_t)&sti, sizeof(sti),
1276 			    SCM_TIME_INFO, SOL_SOCKET);
1277 			if (*mp != NULL)
1278 				mp = &(*mp)->m_next;
1279 		}
1280 	}
1281 #endif
1282 
1283 #define IS2292(inp, x, y)	(((inp)->inp_flags & IN6P_RFC2292) ? (x) : (y))
1284 	/* RFC 2292 sec. 5 */
1285 	if ((inp->inp_flags & IN6P_PKTINFO) != 0) {
1286 		struct in6_pktinfo pi6;
1287 
1288 		if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
1289 #ifdef INET
1290 			struct ip *ip;
1291 
1292 			ip = mtod(m, struct ip *);
1293 			pi6.ipi6_addr.s6_addr32[0] = 0;
1294 			pi6.ipi6_addr.s6_addr32[1] = 0;
1295 			pi6.ipi6_addr.s6_addr32[2] = IPV6_ADDR_INT32_SMP;
1296 			pi6.ipi6_addr.s6_addr32[3] = ip->ip_dst.s_addr;
1297 #else
1298 			/* We won't hit this code */
1299 			bzero(&pi6.ipi6_addr, sizeof(struct in6_addr));
1300 #endif
1301 		} else {
1302 			bcopy(&ip6->ip6_dst, &pi6.ipi6_addr, sizeof(struct in6_addr));
1303 			in6_clearscope(&pi6.ipi6_addr);	/* XXX */
1304 		}
1305 		pi6.ipi6_ifindex =
1306 		    (m && m->m_pkthdr.rcvif) ? m->m_pkthdr.rcvif->if_index : 0;
1307 
1308 		*mp = sbcreatecontrol((caddr_t) &pi6,
1309 		    sizeof(struct in6_pktinfo),
1310 		    IS2292(inp, IPV6_2292PKTINFO, IPV6_PKTINFO), IPPROTO_IPV6);
1311 		if (*mp)
1312 			mp = &(*mp)->m_next;
1313 	}
1314 
1315 	if ((inp->inp_flags & IN6P_HOPLIMIT) != 0) {
1316 		int hlim;
1317 
1318 		if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
1319 #ifdef INET
1320 			struct ip *ip;
1321 
1322 			ip = mtod(m, struct ip *);
1323 			hlim = ip->ip_ttl;
1324 #else
1325 			/* We won't hit this code */
1326 			hlim = 0;
1327 #endif
1328 		} else {
1329 			hlim = ip6->ip6_hlim & 0xff;
1330 		}
1331 		*mp = sbcreatecontrol((caddr_t) &hlim, sizeof(int),
1332 		    IS2292(inp, IPV6_2292HOPLIMIT, IPV6_HOPLIMIT),
1333 		    IPPROTO_IPV6);
1334 		if (*mp)
1335 			mp = &(*mp)->m_next;
1336 	}
1337 
1338 	if ((inp->inp_flags & IN6P_TCLASS) != 0) {
1339 		int tclass;
1340 
1341 		if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
1342 #ifdef INET
1343 			struct ip *ip;
1344 
1345 			ip = mtod(m, struct ip *);
1346 			tclass = ip->ip_tos;
1347 #else
1348 			/* We won't hit this code */
1349 			tclass = 0;
1350 #endif
1351 		} else {
1352 			u_int32_t flowinfo;
1353 
1354 			flowinfo = (u_int32_t)ntohl(ip6->ip6_flow & IPV6_FLOWINFO_MASK);
1355 			flowinfo >>= 20;
1356 			tclass = flowinfo & 0xff;
1357 		}
1358 		*mp = sbcreatecontrol((caddr_t) &tclass, sizeof(int),
1359 		    IPV6_TCLASS, IPPROTO_IPV6);
1360 		if (*mp)
1361 			mp = &(*mp)->m_next;
1362 	}
1363 
1364 	if (v4only != NULL) {
1365 		if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
1366 			*v4only = 1;
1367 		} else {
1368 			*v4only = 0;
1369 		}
1370 	}
1371 
1372 	return (mp);
1373 }
1374 
1375 void
1376 ip6_savecontrol(struct inpcb *inp, struct mbuf *m, struct mbuf **mp)
1377 {
1378 	struct ip6_hdr *ip6;
1379 	int v4only = 0;
1380 
1381 	mp = ip6_savecontrol_v4(inp, m, mp, &v4only);
1382 	if (v4only)
1383 		return;
1384 
1385 	ip6 = mtod(m, struct ip6_hdr *);
1386 	/*
1387 	 * IPV6_HOPOPTS socket option.  Recall that we required super-user
1388 	 * privilege for the option (see ip6_ctloutput), but it might be too
1389 	 * strict, since there might be some hop-by-hop options which can be
1390 	 * returned to normal user.
1391 	 * See also RFC 2292 section 6 (or RFC 3542 section 8).
1392 	 */
1393 	if ((inp->inp_flags & IN6P_HOPOPTS) != 0) {
1394 		/*
1395 		 * Check if a hop-by-hop options header is contatined in the
1396 		 * received packet, and if so, store the options as ancillary
1397 		 * data. Note that a hop-by-hop options header must be
1398 		 * just after the IPv6 header, which is assured through the
1399 		 * IPv6 input processing.
1400 		 */
1401 		if (ip6->ip6_nxt == IPPROTO_HOPOPTS) {
1402 			struct ip6_hbh *hbh;
1403 			int hbhlen;
1404 
1405 			hbh = (struct ip6_hbh *)(ip6 + 1);
1406 			hbhlen = (hbh->ip6h_len + 1) << 3;
1407 
1408 			/*
1409 			 * XXX: We copy the whole header even if a
1410 			 * jumbo payload option is included, the option which
1411 			 * is to be removed before returning according to
1412 			 * RFC2292.
1413 			 * Note: this constraint is removed in RFC3542
1414 			 */
1415 			*mp = sbcreatecontrol((caddr_t)hbh, hbhlen,
1416 			    IS2292(inp, IPV6_2292HOPOPTS, IPV6_HOPOPTS),
1417 			    IPPROTO_IPV6);
1418 			if (*mp)
1419 				mp = &(*mp)->m_next;
1420 		}
1421 	}
1422 
1423 	if ((inp->inp_flags & (IN6P_RTHDR | IN6P_DSTOPTS)) != 0) {
1424 		int nxt = ip6->ip6_nxt, off = sizeof(struct ip6_hdr);
1425 
1426 		/*
1427 		 * Search for destination options headers or routing
1428 		 * header(s) through the header chain, and stores each
1429 		 * header as ancillary data.
1430 		 * Note that the order of the headers remains in
1431 		 * the chain of ancillary data.
1432 		 */
1433 		while (1) {	/* is explicit loop prevention necessary? */
1434 			struct ip6_ext *ip6e = NULL;
1435 			int elen;
1436 
1437 			/*
1438 			 * if it is not an extension header, don't try to
1439 			 * pull it from the chain.
1440 			 */
1441 			switch (nxt) {
1442 			case IPPROTO_DSTOPTS:
1443 			case IPPROTO_ROUTING:
1444 			case IPPROTO_HOPOPTS:
1445 			case IPPROTO_AH: /* is it possible? */
1446 				break;
1447 			default:
1448 				goto loopend;
1449 			}
1450 
1451 			if (off + sizeof(*ip6e) > m->m_len)
1452 				goto loopend;
1453 			ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + off);
1454 			if (nxt == IPPROTO_AH)
1455 				elen = (ip6e->ip6e_len + 2) << 2;
1456 			else
1457 				elen = (ip6e->ip6e_len + 1) << 3;
1458 			if (off + elen > m->m_len)
1459 				goto loopend;
1460 
1461 			switch (nxt) {
1462 			case IPPROTO_DSTOPTS:
1463 				if (!(inp->inp_flags & IN6P_DSTOPTS))
1464 					break;
1465 
1466 				*mp = sbcreatecontrol((caddr_t)ip6e, elen,
1467 				    IS2292(inp,
1468 					IPV6_2292DSTOPTS, IPV6_DSTOPTS),
1469 				    IPPROTO_IPV6);
1470 				if (*mp)
1471 					mp = &(*mp)->m_next;
1472 				break;
1473 			case IPPROTO_ROUTING:
1474 				if (!(inp->inp_flags & IN6P_RTHDR))
1475 					break;
1476 
1477 				*mp = sbcreatecontrol((caddr_t)ip6e, elen,
1478 				    IS2292(inp, IPV6_2292RTHDR, IPV6_RTHDR),
1479 				    IPPROTO_IPV6);
1480 				if (*mp)
1481 					mp = &(*mp)->m_next;
1482 				break;
1483 			case IPPROTO_HOPOPTS:
1484 			case IPPROTO_AH: /* is it possible? */
1485 				break;
1486 
1487 			default:
1488 				/*
1489 				 * other cases have been filtered in the above.
1490 				 * none will visit this case.  here we supply
1491 				 * the code just in case (nxt overwritten or
1492 				 * other cases).
1493 				 */
1494 				goto loopend;
1495 
1496 			}
1497 
1498 			/* proceed with the next header. */
1499 			off += elen;
1500 			nxt = ip6e->ip6e_nxt;
1501 			ip6e = NULL;
1502 		}
1503 	  loopend:
1504 		;
1505 	}
1506 
1507 	if (inp->inp_flags2 & INP_RECVFLOWID) {
1508 		uint32_t flowid, flow_type;
1509 
1510 		flowid = m->m_pkthdr.flowid;
1511 		flow_type = M_HASHTYPE_GET(m);
1512 
1513 		/*
1514 		 * XXX should handle the failure of one or the
1515 		 * other - don't populate both?
1516 		 */
1517 		*mp = sbcreatecontrol((caddr_t) &flowid,
1518 		    sizeof(uint32_t), IPV6_FLOWID, IPPROTO_IPV6);
1519 		if (*mp)
1520 			mp = &(*mp)->m_next;
1521 		*mp = sbcreatecontrol((caddr_t) &flow_type,
1522 		    sizeof(uint32_t), IPV6_FLOWTYPE, IPPROTO_IPV6);
1523 		if (*mp)
1524 			mp = &(*mp)->m_next;
1525 	}
1526 
1527 #ifdef	RSS
1528 	if (inp->inp_flags2 & INP_RECVRSSBUCKETID) {
1529 		uint32_t flowid, flow_type;
1530 		uint32_t rss_bucketid;
1531 
1532 		flowid = m->m_pkthdr.flowid;
1533 		flow_type = M_HASHTYPE_GET(m);
1534 
1535 		if (rss_hash2bucket(flowid, flow_type, &rss_bucketid) == 0) {
1536 			*mp = sbcreatecontrol((caddr_t) &rss_bucketid,
1537 			   sizeof(uint32_t), IPV6_RSSBUCKETID, IPPROTO_IPV6);
1538 			if (*mp)
1539 				mp = &(*mp)->m_next;
1540 		}
1541 	}
1542 #endif
1543 
1544 }
1545 #undef IS2292
1546 
1547 void
1548 ip6_notify_pmtu(struct inpcb *inp, struct sockaddr_in6 *dst, u_int32_t mtu)
1549 {
1550 	struct socket *so;
1551 	struct mbuf *m_mtu;
1552 	struct ip6_mtuinfo mtuctl;
1553 
1554 	KASSERT(inp != NULL, ("%s: inp == NULL", __func__));
1555 	/*
1556 	 * Notify the error by sending IPV6_PATHMTU ancillary data if
1557 	 * application wanted to know the MTU value.
1558 	 * NOTE: we notify disconnected sockets, because some udp
1559 	 * applications keep sending sockets disconnected.
1560 	 * NOTE: our implementation doesn't notify connected sockets that has
1561 	 * foreign address that is different than given destination addresses
1562 	 * (this is permitted by RFC 3542).
1563 	 */
1564 	if ((inp->inp_flags & IN6P_MTU) == 0 || (
1565 	    !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr) &&
1566 	    !IN6_ARE_ADDR_EQUAL(&inp->in6p_faddr, &dst->sin6_addr)))
1567 		return;
1568 
1569 	mtuctl.ip6m_mtu = mtu;
1570 	mtuctl.ip6m_addr = *dst;
1571 	if (sa6_recoverscope(&mtuctl.ip6m_addr))
1572 		return;
1573 
1574 	if ((m_mtu = sbcreatecontrol((caddr_t)&mtuctl, sizeof(mtuctl),
1575 	    IPV6_PATHMTU, IPPROTO_IPV6)) == NULL)
1576 		return;
1577 
1578 	so =  inp->inp_socket;
1579 	if (sbappendaddr(&so->so_rcv, (struct sockaddr *)dst, NULL, m_mtu)
1580 	    == 0) {
1581 		m_freem(m_mtu);
1582 		/* XXX: should count statistics */
1583 	} else
1584 		sorwakeup(so);
1585 }
1586 
1587 /*
1588  * Get pointer to the previous header followed by the header
1589  * currently processed.
1590  */
1591 int
1592 ip6_get_prevhdr(const struct mbuf *m, int off)
1593 {
1594 	struct ip6_ext ip6e;
1595 	struct ip6_hdr *ip6;
1596 	int len, nlen, nxt;
1597 
1598 	if (off == sizeof(struct ip6_hdr))
1599 		return (offsetof(struct ip6_hdr, ip6_nxt));
1600 	if (off < sizeof(struct ip6_hdr))
1601 		panic("%s: off < sizeof(struct ip6_hdr)", __func__);
1602 
1603 	ip6 = mtod(m, struct ip6_hdr *);
1604 	nxt = ip6->ip6_nxt;
1605 	len = sizeof(struct ip6_hdr);
1606 	nlen = 0;
1607 	while (len < off) {
1608 		m_copydata(m, len, sizeof(ip6e), (caddr_t)&ip6e);
1609 		switch (nxt) {
1610 		case IPPROTO_FRAGMENT:
1611 			nlen = sizeof(struct ip6_frag);
1612 			break;
1613 		case IPPROTO_AH:
1614 			nlen = (ip6e.ip6e_len + 2) << 2;
1615 			break;
1616 		default:
1617 			nlen = (ip6e.ip6e_len + 1) << 3;
1618 		}
1619 		len += nlen;
1620 		nxt = ip6e.ip6e_nxt;
1621 	}
1622 	return (len - nlen);
1623 }
1624 
1625 /*
1626  * get next header offset.  m will be retained.
1627  */
1628 int
1629 ip6_nexthdr(const struct mbuf *m, int off, int proto, int *nxtp)
1630 {
1631 	struct ip6_hdr ip6;
1632 	struct ip6_ext ip6e;
1633 	struct ip6_frag fh;
1634 
1635 	/* just in case */
1636 	if (m == NULL)
1637 		panic("ip6_nexthdr: m == NULL");
1638 	if ((m->m_flags & M_PKTHDR) == 0 || m->m_pkthdr.len < off)
1639 		return -1;
1640 
1641 	switch (proto) {
1642 	case IPPROTO_IPV6:
1643 		if (m->m_pkthdr.len < off + sizeof(ip6))
1644 			return -1;
1645 		m_copydata(m, off, sizeof(ip6), (caddr_t)&ip6);
1646 		if (nxtp)
1647 			*nxtp = ip6.ip6_nxt;
1648 		off += sizeof(ip6);
1649 		return off;
1650 
1651 	case IPPROTO_FRAGMENT:
1652 		/*
1653 		 * terminate parsing if it is not the first fragment,
1654 		 * it does not make sense to parse through it.
1655 		 */
1656 		if (m->m_pkthdr.len < off + sizeof(fh))
1657 			return -1;
1658 		m_copydata(m, off, sizeof(fh), (caddr_t)&fh);
1659 		/* IP6F_OFF_MASK = 0xfff8(BigEndian), 0xf8ff(LittleEndian) */
1660 		if (fh.ip6f_offlg & IP6F_OFF_MASK)
1661 			return -1;
1662 		if (nxtp)
1663 			*nxtp = fh.ip6f_nxt;
1664 		off += sizeof(struct ip6_frag);
1665 		return off;
1666 
1667 	case IPPROTO_AH:
1668 		if (m->m_pkthdr.len < off + sizeof(ip6e))
1669 			return -1;
1670 		m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e);
1671 		if (nxtp)
1672 			*nxtp = ip6e.ip6e_nxt;
1673 		off += (ip6e.ip6e_len + 2) << 2;
1674 		return off;
1675 
1676 	case IPPROTO_HOPOPTS:
1677 	case IPPROTO_ROUTING:
1678 	case IPPROTO_DSTOPTS:
1679 		if (m->m_pkthdr.len < off + sizeof(ip6e))
1680 			return -1;
1681 		m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e);
1682 		if (nxtp)
1683 			*nxtp = ip6e.ip6e_nxt;
1684 		off += (ip6e.ip6e_len + 1) << 3;
1685 		return off;
1686 
1687 	case IPPROTO_NONE:
1688 	case IPPROTO_ESP:
1689 	case IPPROTO_IPCOMP:
1690 		/* give up */
1691 		return -1;
1692 
1693 	default:
1694 		return -1;
1695 	}
1696 
1697 	/* NOTREACHED */
1698 }
1699 
1700 /*
1701  * get offset for the last header in the chain.  m will be kept untainted.
1702  */
1703 int
1704 ip6_lasthdr(const struct mbuf *m, int off, int proto, int *nxtp)
1705 {
1706 	int newoff;
1707 	int nxt;
1708 
1709 	if (!nxtp) {
1710 		nxt = -1;
1711 		nxtp = &nxt;
1712 	}
1713 	while (1) {
1714 		newoff = ip6_nexthdr(m, off, proto, nxtp);
1715 		if (newoff < 0)
1716 			return off;
1717 		else if (newoff < off)
1718 			return -1;	/* invalid */
1719 		else if (newoff == off)
1720 			return newoff;
1721 
1722 		off = newoff;
1723 		proto = *nxtp;
1724 	}
1725 }
1726 
1727 /*
1728  * System control for IP6
1729  */
1730 
1731 u_char	inet6ctlerrmap[PRC_NCMDS] = {
1732 	0,		0,		0,		0,
1733 	0,		EMSGSIZE,	EHOSTDOWN,	EHOSTUNREACH,
1734 	EHOSTUNREACH,	EHOSTUNREACH,	ECONNREFUSED,	ECONNREFUSED,
1735 	EMSGSIZE,	EHOSTUNREACH,	0,		0,
1736 	0,		0,		EHOSTUNREACH,	0,
1737 	ENOPROTOOPT,	ECONNREFUSED
1738 };
1739