icmp6.c revision 1.245
1/*	$NetBSD: icmp6.c,v 1.245 2020/06/12 11:04:45 roy Exp $	*/
2/*	$KAME: icmp6.c,v 1.217 2001/06/20 15:03:29 jinmei Exp $	*/
3
4/*
5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the project nor the names of its contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33/*
34 * Copyright (c) 1982, 1986, 1988, 1993
35 *	The Regents of the University of California.  All rights reserved.
36 *
37 * Redistribution and use in source and binary forms, with or without
38 * modification, are permitted provided that the following conditions
39 * are met:
40 * 1. Redistributions of source code must retain the above copyright
41 *    notice, this list of conditions and the following disclaimer.
42 * 2. Redistributions in binary form must reproduce the above copyright
43 *    notice, this list of conditions and the following disclaimer in the
44 *    documentation and/or other materials provided with the distribution.
45 * 3. Neither the name of the University nor the names of its contributors
46 *    may be used to endorse or promote products derived from this software
47 *    without specific prior written permission.
48 *
49 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
50 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
52 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
53 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
54 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
55 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
56 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
57 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
58 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
59 * SUCH DAMAGE.
60 *
61 *	@(#)ip_icmp.c	8.2 (Berkeley) 1/4/94
62 */
63
64#include <sys/cdefs.h>
65__KERNEL_RCSID(0, "$NetBSD: icmp6.c,v 1.245 2020/06/12 11:04:45 roy Exp $");
66
67#ifdef _KERNEL_OPT
68#include "opt_compat_netbsd.h"
69#include "opt_inet.h"
70#include "opt_ipsec.h"
71#endif
72
73#include <sys/param.h>
74#include <sys/systm.h>
75#include <sys/kmem.h>
76#include <sys/mbuf.h>
77#include <sys/protosw.h>
78#include <sys/socket.h>
79#include <sys/socketvar.h>
80#include <sys/time.h>
81#include <sys/kernel.h>
82#include <sys/syslog.h>
83#include <sys/domain.h>
84#include <sys/sysctl.h>
85
86#include <net/if.h>
87#include <net/route.h>
88#include <net/if_dl.h>
89#include <net/if_types.h>
90
91#include <netinet/in.h>
92#include <netinet/in_var.h>
93#include <netinet/ip6.h>
94#include <netinet/wqinput.h>
95#include <netinet6/ip6_var.h>
96#include <netinet6/ip6_private.h>
97#include <netinet/icmp6.h>
98#include <netinet6/icmp6_private.h>
99#include <netinet6/mld6_var.h>
100#include <netinet6/in6_pcb.h>
101#include <netinet6/nd6.h>
102#include <netinet6/in6_ifattach.h>
103#include <netinet6/ip6protosw.h>
104#include <netinet6/scope6_var.h>
105
106#ifdef IPSEC
107#include <netipsec/ipsec.h>
108#include <netipsec/ipsec6.h>
109#include <netipsec/key.h>
110#endif
111
112#include "faith.h"
113#if defined(NFAITH) && 0 < NFAITH
114#include <net/if_faith.h>
115#endif
116
117extern struct domain inet6domain;
118
119percpu_t *icmp6stat_percpu;
120
121extern struct inpcbtable raw6cbtable;
122extern int icmp6errppslim;
123static int icmp6errpps_count = 0;
124static struct timeval icmp6errppslim_last;
125extern int icmp6_nodeinfo;
126
127/*
128 * List of callbacks to notify when Path MTU changes are made.
129 */
130struct icmp6_mtudisc_callback {
131	LIST_ENTRY(icmp6_mtudisc_callback) mc_list;
132	void (*mc_func)(struct in6_addr *);
133};
134
135LIST_HEAD(, icmp6_mtudisc_callback) icmp6_mtudisc_callbacks =
136    LIST_HEAD_INITIALIZER(&icmp6_mtudisc_callbacks);
137
138static struct rttimer_queue *icmp6_mtudisc_timeout_q = NULL;
139extern int pmtu_expire;
140
141/* XXX do these values make any sense? */
142static int icmp6_mtudisc_hiwat = 1280;
143static int icmp6_mtudisc_lowat = 256;
144
145/*
146 * keep track of # of redirect routes.
147 */
148static struct rttimer_queue *icmp6_redirect_timeout_q = NULL;
149
150/* XXX experimental, turned off */
151static int icmp6_redirect_hiwat = -1;
152static int icmp6_redirect_lowat = -1;
153
154/* Protect mtudisc and redirect stuffs */
155static kmutex_t icmp6_mtx __cacheline_aligned;
156
157static void icmp6_errcount(u_int, int, int);
158static int icmp6_rip6_input(struct mbuf **, int);
159static void icmp6_reflect(struct mbuf *, size_t);
160static int icmp6_ratelimit(const struct in6_addr *, const int, const int);
161static const char *icmp6_redirect_diag(char *, size_t, struct in6_addr *,
162    struct in6_addr *, struct in6_addr *);
163static void icmp6_redirect_input(struct mbuf *, int);
164static struct mbuf *ni6_input(struct mbuf *, int);
165static struct mbuf *ni6_nametodns(const char *, int, int);
166static int ni6_dnsmatch(const char *, int, const char *, int);
167static int ni6_addrs(struct icmp6_nodeinfo *, struct ifnet **, char *,
168    struct psref *);
169static int ni6_store_addrs(struct icmp6_nodeinfo *, struct icmp6_nodeinfo *,
170    struct ifnet *, int);
171static int icmp6_notify_error(struct mbuf *, int, int, int);
172static struct rtentry *icmp6_mtudisc_clone(struct sockaddr *);
173static void icmp6_mtudisc_timeout(struct rtentry *, struct rttimer *);
174static void icmp6_redirect_timeout(struct rtentry *, struct rttimer *);
175static void sysctl_net_inet6_icmp6_setup(struct sysctllog **);
176
177/* workqueue-based pr_input */
178static struct wqinput *icmp6_wqinput;
179static void _icmp6_input(struct mbuf *m, int off, int proto);
180
181void
182icmp6_init(void)
183{
184
185	sysctl_net_inet6_icmp6_setup(NULL);
186	mld_init();
187
188	mutex_init(&icmp6_mtx, MUTEX_DEFAULT, IPL_NONE);
189	mutex_enter(&icmp6_mtx);
190	icmp6_mtudisc_timeout_q = rt_timer_queue_create(pmtu_expire);
191	icmp6_redirect_timeout_q = rt_timer_queue_create(icmp6_redirtimeout);
192	mutex_exit(&icmp6_mtx);
193
194	icmp6stat_percpu = percpu_alloc(sizeof(uint64_t) * ICMP6_NSTATS);
195
196	icmp6_wqinput = wqinput_create("icmp6", _icmp6_input);
197}
198
199static void
200icmp6_errcount(u_int base, int type, int code)
201{
202	switch (type) {
203	case ICMP6_DST_UNREACH:
204		switch (code) {
205		case ICMP6_DST_UNREACH_NOROUTE:
206			ICMP6_STATINC(base + ICMP6_ERRSTAT_DST_UNREACH_NOROUTE);
207			return;
208		case ICMP6_DST_UNREACH_ADMIN:
209			ICMP6_STATINC(base + ICMP6_ERRSTAT_DST_UNREACH_ADMIN);
210			return;
211		case ICMP6_DST_UNREACH_BEYONDSCOPE:
212			ICMP6_STATINC(base +
213				      ICMP6_ERRSTAT_DST_UNREACH_BEYONDSCOPE);
214			return;
215		case ICMP6_DST_UNREACH_ADDR:
216			ICMP6_STATINC(base + ICMP6_ERRSTAT_DST_UNREACH_ADDR);
217			return;
218		case ICMP6_DST_UNREACH_NOPORT:
219			ICMP6_STATINC(base + ICMP6_ERRSTAT_DST_UNREACH_NOPORT);
220			return;
221		}
222		break;
223	case ICMP6_PACKET_TOO_BIG:
224		ICMP6_STATINC(base + ICMP6_ERRSTAT_PACKET_TOO_BIG);
225		return;
226	case ICMP6_TIME_EXCEEDED:
227		switch (code) {
228		case ICMP6_TIME_EXCEED_TRANSIT:
229			ICMP6_STATINC(base + ICMP6_ERRSTAT_TIME_EXCEED_TRANSIT);
230			return;
231		case ICMP6_TIME_EXCEED_REASSEMBLY:
232			ICMP6_STATINC(base +
233				      ICMP6_ERRSTAT_TIME_EXCEED_REASSEMBLY);
234			return;
235		}
236		break;
237	case ICMP6_PARAM_PROB:
238		switch (code) {
239		case ICMP6_PARAMPROB_HEADER:
240			ICMP6_STATINC(base + ICMP6_ERRSTAT_PARAMPROB_HEADER);
241			return;
242		case ICMP6_PARAMPROB_NEXTHEADER:
243			ICMP6_STATINC(base +
244				      ICMP6_ERRSTAT_PARAMPROB_NEXTHEADER);
245			return;
246		case ICMP6_PARAMPROB_OPTION:
247			ICMP6_STATINC(base + ICMP6_ERRSTAT_PARAMPROB_OPTION);
248			return;
249		}
250		break;
251	case ND_REDIRECT:
252		ICMP6_STATINC(base + ICMP6_ERRSTAT_REDIRECT);
253		return;
254	}
255	ICMP6_STATINC(base + ICMP6_ERRSTAT_UNKNOWN);
256}
257
258/*
259 * Register a Path MTU Discovery callback.
260 */
261void
262icmp6_mtudisc_callback_register(void (*func)(struct in6_addr *))
263{
264	struct icmp6_mtudisc_callback *mc, *new;
265
266	new = kmem_alloc(sizeof(*mc), KM_SLEEP);
267
268	mutex_enter(&icmp6_mtx);
269	for (mc = LIST_FIRST(&icmp6_mtudisc_callbacks); mc != NULL;
270	     mc = LIST_NEXT(mc, mc_list)) {
271		if (mc->mc_func == func) {
272			mutex_exit(&icmp6_mtx);
273			kmem_free(new, sizeof(*mc));
274			return;
275		}
276	}
277
278	new->mc_func = func;
279	LIST_INSERT_HEAD(&icmp6_mtudisc_callbacks, new, mc_list);
280	mutex_exit(&icmp6_mtx);
281}
282
283/*
284 * A wrapper function for icmp6_error() necessary when the erroneous packet
285 * may not contain enough scope zone information.
286 */
287void
288icmp6_error2(struct mbuf *m, int type, int code, int param,
289	struct ifnet *ifp, struct in6_addr *src)
290{
291	struct ip6_hdr *ip6;
292
293	KASSERT(ifp != NULL);
294
295	if (m->m_len < sizeof(struct ip6_hdr)) {
296		m = m_pullup(m, sizeof(struct ip6_hdr));
297		if (m == NULL)
298			return;
299	}
300
301	ip6 = mtod(m, struct ip6_hdr *);
302
303	if (in6_setscope(&ip6->ip6_src, ifp, NULL) != 0)
304		goto out;
305	if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0)
306		goto out;
307
308	*src = ip6->ip6_src;
309	icmp6_error(m, type, code, param);
310	return;
311
312out:
313	m_freem(m);
314}
315
316/*
317 * Generate an error packet of type error in response to bad IP6 packet.
318 */
319void
320icmp6_error(struct mbuf *m, int type, int code, int param)
321{
322	struct ip6_hdr *oip6, *nip6;
323	struct icmp6_hdr *icmp6;
324	u_int preplen;
325	int off;
326	int nxt;
327
328	ICMP6_STATINC(ICMP6_STAT_ERROR);
329
330	/* count per-type-code statistics */
331	icmp6_errcount(ICMP6_STAT_OUTERRHIST, type, code);
332
333	if (m->m_flags & M_DECRYPTED) {
334		ICMP6_STATINC(ICMP6_STAT_CANTERROR);
335		goto freeit;
336	}
337
338	if (M_UNWRITABLE(m, sizeof(struct ip6_hdr)) &&
339	    (m = m_pullup(m, sizeof(struct ip6_hdr))) == NULL)
340		return;
341	oip6 = mtod(m, struct ip6_hdr *);
342
343	/*
344	 * If the destination address of the erroneous packet is a multicast
345	 * address, or the packet was sent using link-layer multicast,
346	 * we should basically suppress sending an error (RFC 2463, Section
347	 * 2.4).
348	 * We have two exceptions (the item e.2 in that section):
349	 * - the Packet Too Big message can be sent for path MTU discovery.
350	 * - the Parameter Problem Message that can be allowed an icmp6 error
351	 *   in the option type field.  This check has been done in
352	 *   ip6_unknown_opt(), so we can just check the type and code.
353	 */
354	if ((m->m_flags & (M_BCAST|M_MCAST) ||
355	     IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) &&
356	    (type != ICMP6_PACKET_TOO_BIG &&
357	     (type != ICMP6_PARAM_PROB ||
358	      code != ICMP6_PARAMPROB_OPTION)))
359		goto freeit;
360
361	/*
362	 * RFC 2463, 2.4 (e.5): source address check.
363	 * XXX: the case of anycast source?
364	 */
365	if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) ||
366	    IN6_IS_ADDR_MULTICAST(&oip6->ip6_src))
367		goto freeit;
368
369	/*
370	 * If we are about to send ICMPv6 against ICMPv6 error/redirect,
371	 * don't do it.
372	 */
373	nxt = -1;
374	off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt);
375	if (off >= 0 && nxt == IPPROTO_ICMPV6) {
376		struct icmp6_hdr *icp;
377
378		IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off,
379			sizeof(*icp));
380		if (icp == NULL) {
381			ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
382			return;
383		}
384		if (icp->icmp6_type < ICMP6_ECHO_REQUEST ||
385		    icp->icmp6_type == ND_REDIRECT) {
386			/*
387			 * ICMPv6 error
388			 * Special case: for redirect (which is
389			 * informational) we must not send icmp6 error.
390			 */
391			ICMP6_STATINC(ICMP6_STAT_CANTERROR);
392			goto freeit;
393		} else {
394			/* ICMPv6 informational - send the error */
395		}
396	} else {
397		/* non-ICMPv6 - send the error */
398	}
399
400	oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */
401
402	/* Finally, do rate limitation check. */
403	if (icmp6_ratelimit(&oip6->ip6_src, type, code)) {
404		ICMP6_STATINC(ICMP6_STAT_TOOFREQ);
405		goto freeit;
406	}
407
408	/*
409	 * OK, ICMP6 can be generated.
410	 */
411
412	if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN)
413		m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len);
414
415	preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
416	M_PREPEND(m, preplen, M_DONTWAIT);
417	if (m && M_UNWRITABLE(m, preplen))
418		m = m_pullup(m, preplen);
419	if (m == NULL) {
420		nd6log(LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__);
421		return;
422	}
423
424	nip6 = mtod(m, struct ip6_hdr *);
425	nip6->ip6_src  = oip6->ip6_src;
426	nip6->ip6_dst  = oip6->ip6_dst;
427
428	in6_clearscope(&oip6->ip6_src);
429	in6_clearscope(&oip6->ip6_dst);
430
431	icmp6 = (struct icmp6_hdr *)(nip6 + 1);
432	icmp6->icmp6_type = type;
433	icmp6->icmp6_code = code;
434	icmp6->icmp6_pptr = htonl((u_int32_t)param);
435
436	/*
437	 * icmp6_reflect() is designed to be in the input path.
438	 * icmp6_error() can be called from both input and output path,
439	 * and if we are in output path rcvif could contain bogus value.
440	 * clear m->m_pkthdr.rcvif for safety, we should have enough scope
441	 * information in ip header (nip6).
442	 */
443	m_reset_rcvif(m);
444
445	ICMP6_STATINC(ICMP6_STAT_OUTHIST + type);
446
447	/* header order: IPv6 - ICMPv6 */
448	icmp6_reflect(m, sizeof(struct ip6_hdr));
449
450	return;
451
452freeit:
453	/*
454	 * If we can't tell whether or not we can generate ICMP6, free it.
455	 */
456	m_freem(m);
457}
458
459/*
460 * Process a received ICMP6 message.
461 */
462static void
463_icmp6_input(struct mbuf *m, int off, int proto)
464{
465	struct mbuf *n;
466	struct ip6_hdr *ip6, *nip6;
467	struct icmp6_hdr *icmp6, *nicmp6;
468	int icmp6len = m->m_pkthdr.len - off;
469	int code, sum;
470	struct ifnet *rcvif;
471	struct psref psref;
472	char ip6buf[INET6_ADDRSTRLEN], ip6buf2[INET6_ADDRSTRLEN];
473
474	rcvif = m_get_rcvif_psref(m, &psref);
475	if (__predict_false(rcvif == NULL))
476		goto freeit;
477
478#define ICMP6_MAXLEN (sizeof(*nip6) + sizeof(*nicmp6) + 4)
479	KASSERT(ICMP6_MAXLEN < MCLBYTES);
480	icmp6_ifstat_inc(rcvif, ifs6_in_msg);
481
482	/*
483	 * Locate icmp6 structure in mbuf, and check
484	 * that not corrupted and of at least minimum length
485	 */
486
487	if (icmp6len < sizeof(struct icmp6_hdr)) {
488		ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
489		icmp6_ifstat_inc(rcvif, ifs6_in_error);
490		goto freeit;
491	}
492
493	if (m->m_len < sizeof(struct ip6_hdr)) {
494		m = m_pullup(m, sizeof(struct ip6_hdr));
495		if (m == NULL) {
496			ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
497			icmp6_ifstat_inc(rcvif, ifs6_in_error);
498			goto freeit;
499		}
500	}
501
502	ip6 = mtod(m, struct ip6_hdr *);
503	IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6));
504	if (icmp6 == NULL) {
505		ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
506		icmp6_ifstat_inc(rcvif, ifs6_in_error);
507		goto freeit;
508	}
509
510	/*
511	 * Enforce alignment requirements that are violated in
512	 * some cases, see kern/50766 for details.
513	 */
514	if (IP6_HDR_ALIGNED_P(icmp6) == 0) {
515		m = m_copyup(m, off + sizeof(struct icmp6_hdr), 0);
516		if (m == NULL) {
517			ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
518			icmp6_ifstat_inc(rcvif, ifs6_in_error);
519			goto freeit;
520		}
521		ip6 = mtod(m, struct ip6_hdr *);
522		icmp6 = (struct icmp6_hdr *)(mtod(m, char *) + off);
523	}
524	KASSERT(IP6_HDR_ALIGNED_P(icmp6));
525
526	/*
527	 * calculate the checksum
528	 */
529	if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) {
530		nd6log(LOG_ERR, "ICMP6 checksum error(%d|%x) %s\n",
531		    icmp6->icmp6_type, sum, IN6_PRINT(ip6buf, &ip6->ip6_src));
532		ICMP6_STATINC(ICMP6_STAT_CHECKSUM);
533		icmp6_ifstat_inc(rcvif, ifs6_in_error);
534		goto freeit;
535	}
536
537#if defined(NFAITH) && 0 < NFAITH
538	if (faithprefix(&ip6->ip6_dst)) {
539		/*
540		 * Deliver very specific ICMP6 type only.
541		 * This is important to deliver TOOBIG.  Otherwise PMTUD
542		 * will not work.
543		 */
544		switch (icmp6->icmp6_type) {
545		case ICMP6_DST_UNREACH:
546		case ICMP6_PACKET_TOO_BIG:
547		case ICMP6_TIME_EXCEEDED:
548			break;
549		default:
550			goto freeit;
551		}
552	}
553#endif
554
555	code = icmp6->icmp6_code;
556	ICMP6_STATINC(ICMP6_STAT_INHIST + icmp6->icmp6_type);
557
558	switch (icmp6->icmp6_type) {
559	case ICMP6_DST_UNREACH:
560		icmp6_ifstat_inc(rcvif, ifs6_in_dstunreach);
561		switch (code) {
562		case ICMP6_DST_UNREACH_NOROUTE:
563			code = PRC_UNREACH_NET;
564			break;
565		case ICMP6_DST_UNREACH_ADMIN:
566			icmp6_ifstat_inc(rcvif, ifs6_in_adminprohib);
567			code = PRC_UNREACH_PROTOCOL; /* is this a good code? */
568			break;
569		case ICMP6_DST_UNREACH_ADDR:
570			code = PRC_HOSTDEAD;
571			break;
572		case ICMP6_DST_UNREACH_BEYONDSCOPE:
573			/* I mean "source address was incorrect." */
574			code = PRC_UNREACH_NET;
575			break;
576		case ICMP6_DST_UNREACH_NOPORT:
577			code = PRC_UNREACH_PORT;
578			break;
579		default:
580			goto badcode;
581		}
582		goto deliver;
583
584	case ICMP6_PACKET_TOO_BIG:
585		icmp6_ifstat_inc(rcvif, ifs6_in_pkttoobig);
586
587		/*
588		 * MTU is checked in icmp6_mtudisc.
589		 */
590		code = PRC_MSGSIZE;
591
592		/*
593		 * Updating the path MTU will be done after examining
594		 * intermediate extension headers.
595		 */
596		goto deliver;
597
598	case ICMP6_TIME_EXCEEDED:
599		icmp6_ifstat_inc(rcvif, ifs6_in_timeexceed);
600		switch (code) {
601		case ICMP6_TIME_EXCEED_TRANSIT:
602			code = PRC_TIMXCEED_INTRANS;
603			break;
604		case ICMP6_TIME_EXCEED_REASSEMBLY:
605			code = PRC_TIMXCEED_REASS;
606			break;
607		default:
608			goto badcode;
609		}
610		goto deliver;
611
612	case ICMP6_PARAM_PROB:
613		icmp6_ifstat_inc(rcvif, ifs6_in_paramprob);
614		switch (code) {
615		case ICMP6_PARAMPROB_NEXTHEADER:
616			code = PRC_UNREACH_PROTOCOL;
617			break;
618		case ICMP6_PARAMPROB_HEADER:
619		case ICMP6_PARAMPROB_OPTION:
620			code = PRC_PARAMPROB;
621			break;
622		default:
623			goto badcode;
624		}
625		goto deliver;
626
627	case ICMP6_ECHO_REQUEST:
628		icmp6_ifstat_inc(rcvif, ifs6_in_echo);
629		if (code != 0)
630			goto badcode;
631		/*
632		 * Copy mbuf to send to two data paths: userland socket(s),
633		 * and to the querier (echo reply).
634		 * m: a copy for socket, n: a copy for querier
635		 *
636		 * If the first mbuf is shared, or the first mbuf is too short,
637		 * copy the first part of the data into a fresh mbuf.
638		 * Otherwise, we will wrongly overwrite both copies.
639		 */
640		if ((n = m_copypacket(m, M_DONTWAIT)) == NULL) {
641			/* Give up local */
642			n = m;
643			m = NULL;
644		} else if (M_UNWRITABLE(n, off + sizeof(struct icmp6_hdr))) {
645			struct mbuf *n0 = n;
646
647			/*
648			 * Prepare an internal mbuf.  m_pullup() doesn't
649			 * always copy the length we specified.
650			 */
651			if ((n = m_dup(n0, 0, M_COPYALL, M_DONTWAIT)) == NULL) {
652				/* Give up local */
653				n = m;
654				m = NULL;
655			}
656			m_freem(n0);
657		}
658		IP6_EXTHDR_GET(nicmp6, struct icmp6_hdr *, n, off,
659		    sizeof(*nicmp6));
660		if (nicmp6 == NULL)
661			goto freeit;
662		nicmp6->icmp6_type = ICMP6_ECHO_REPLY;
663		nicmp6->icmp6_code = 0;
664		if (n) {
665			uint64_t *icmp6s = ICMP6_STAT_GETREF();
666			icmp6s[ICMP6_STAT_REFLECT]++;
667			icmp6s[ICMP6_STAT_OUTHIST + ICMP6_ECHO_REPLY]++;
668			ICMP6_STAT_PUTREF();
669			icmp6_reflect(n, off);
670		}
671		if (!m)
672			goto freeit;
673		break;
674
675	case ICMP6_ECHO_REPLY:
676		icmp6_ifstat_inc(rcvif, ifs6_in_echoreply);
677		if (code != 0)
678			goto badcode;
679		break;
680
681	case MLD_LISTENER_QUERY:
682	case MLD_LISTENER_REPORT:
683		if (icmp6len < sizeof(struct mld_hdr))
684			goto badlen;
685		if (icmp6->icmp6_type == MLD_LISTENER_QUERY) /* XXX: ugly... */
686			icmp6_ifstat_inc(rcvif, ifs6_in_mldquery);
687		else
688			icmp6_ifstat_inc(rcvif, ifs6_in_mldreport);
689		if ((n = m_copypacket(m, M_DONTWAIT)) == NULL) {
690			/* give up local */
691			mld_input(m, off);
692			m = NULL;
693			goto freeit;
694		}
695		mld_input(n, off);
696		/* m stays. */
697		break;
698
699	case MLD_LISTENER_DONE:
700		icmp6_ifstat_inc(rcvif, ifs6_in_mlddone);
701		if (icmp6len < sizeof(struct mld_hdr))	/* necessary? */
702			goto badlen;
703		break;		/* nothing to be done in kernel */
704
705	case MLD_MTRACE_RESP:
706	case MLD_MTRACE:
707		/* XXX: these two are experimental.  not officially defined. */
708		/* XXX: per-interface statistics? */
709		break;		/* just pass it to applications */
710
711	case ICMP6_WRUREQUEST:	/* ICMP6_FQDN_QUERY */
712	    {
713		enum { WRU, FQDN } mode;
714
715		if (!icmp6_nodeinfo)
716			break;
717
718		if (icmp6len == sizeof(struct icmp6_hdr) + 4)
719			mode = WRU;
720		else if (icmp6len >= sizeof(struct icmp6_nodeinfo))
721			mode = FQDN;
722		else
723			goto badlen;
724
725		if (mode == FQDN) {
726			n = m_copypacket(m, M_DONTWAIT);
727			if (n)
728				n = ni6_input(n, off);
729		} else {
730			u_char *p;
731			int maxhlen;
732
733			if ((icmp6_nodeinfo & 5) != 5)
734				break;
735
736			if (code != 0)
737				goto badcode;
738			MGETHDR(n, M_DONTWAIT, m->m_type);
739			if (n && ICMP6_MAXLEN > MHLEN) {
740				MCLGET(n, M_DONTWAIT);
741				if ((n->m_flags & M_EXT) == 0) {
742					m_free(n);
743					n = NULL;
744				}
745			}
746			if (n == NULL) {
747				/* Give up remote */
748				break;
749			}
750			m_reset_rcvif(n);
751			n->m_len = 0;
752			maxhlen = M_TRAILINGSPACE(n) - ICMP6_MAXLEN;
753			if (maxhlen < 0) {
754				m_free(n);
755				break;
756			}
757			if (maxhlen > hostnamelen)
758				maxhlen = hostnamelen;
759			/*
760			 * Copy IPv6 and ICMPv6 only.
761			 */
762			nip6 = mtod(n, struct ip6_hdr *);
763			memcpy(nip6, ip6, sizeof(struct ip6_hdr));
764			nicmp6 = (struct icmp6_hdr *)(nip6 + 1);
765			memcpy(nicmp6, icmp6, sizeof(struct icmp6_hdr));
766
767			p = (u_char *)(nicmp6 + 1);
768			memset(p, 0, 4);
769			memcpy(p + 4, hostname, maxhlen); /* meaningless TTL */
770
771			m_copy_pkthdr(n, m);
772			n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
773				sizeof(struct icmp6_hdr) + 4 + maxhlen;
774			nicmp6->icmp6_type = ICMP6_WRUREPLY;
775			nicmp6->icmp6_code = 0;
776		}
777		if (n) {
778			uint64_t *icmp6s = ICMP6_STAT_GETREF();
779			icmp6s[ICMP6_STAT_REFLECT]++;
780			icmp6s[ICMP6_STAT_OUTHIST + ICMP6_WRUREPLY]++;
781			ICMP6_STAT_PUTREF();
782			icmp6_reflect(n, sizeof(struct ip6_hdr));
783		}
784		break;
785	    }
786
787	case ICMP6_WRUREPLY:
788		if (code != 0)
789			goto badcode;
790		break;
791
792	case ND_ROUTER_SOLICIT:
793		icmp6_ifstat_inc(rcvif, ifs6_in_routersolicit);
794		/* FALLTHROUGH */
795	case ND_ROUTER_ADVERT:
796		if (icmp6->icmp6_type == ND_ROUTER_ADVERT)
797			icmp6_ifstat_inc(rcvif, ifs6_in_routeradvert);
798		if (code != 0)
799			goto badcode;
800		if ((icmp6->icmp6_type == ND_ROUTER_SOLICIT &&
801		    icmp6len < sizeof(struct nd_router_solicit)) ||
802		    (icmp6->icmp6_type == ND_ROUTER_ADVERT &&
803		    icmp6len < sizeof(struct nd_router_advert)))
804			goto badlen;
805		if ((n = m_copypacket(m, M_DONTWAIT)) == NULL) {
806			/* give up local */
807			nd6_rtr_cache(m, off, icmp6len, icmp6->icmp6_type);
808			m = NULL;
809			goto freeit;
810		}
811		nd6_rtr_cache(n, off, icmp6len, icmp6->icmp6_type);
812		/* m stays. */
813		break;
814
815	case ND_NEIGHBOR_SOLICIT:
816		icmp6_ifstat_inc(rcvif, ifs6_in_neighborsolicit);
817		if (code != 0)
818			goto badcode;
819		if (icmp6len < sizeof(struct nd_neighbor_solicit))
820			goto badlen;
821		if ((n = m_copypacket(m, M_DONTWAIT)) == NULL) {
822			/* give up local */
823			nd6_ns_input(m, off, icmp6len);
824			m = NULL;
825			goto freeit;
826		}
827		nd6_ns_input(n, off, icmp6len);
828		/* m stays. */
829		break;
830
831	case ND_NEIGHBOR_ADVERT:
832		icmp6_ifstat_inc(rcvif, ifs6_in_neighboradvert);
833		if (code != 0)
834			goto badcode;
835		if (icmp6len < sizeof(struct nd_neighbor_advert))
836			goto badlen;
837		if ((n = m_copypacket(m, M_DONTWAIT)) == NULL) {
838			/* give up local */
839			nd6_na_input(m, off, icmp6len);
840			m = NULL;
841			goto freeit;
842		}
843		nd6_na_input(n, off, icmp6len);
844		/* m stays. */
845		break;
846
847	case ND_REDIRECT:
848		icmp6_ifstat_inc(rcvif, ifs6_in_redirect);
849		if (code != 0)
850			goto badcode;
851		if (icmp6len < sizeof(struct nd_redirect))
852			goto badlen;
853		if ((n = m_copypacket(m, M_DONTWAIT)) == NULL) {
854			/* give up local */
855			icmp6_redirect_input(m, off);
856			m = NULL;
857			goto freeit;
858		}
859		icmp6_redirect_input(n, off);
860		/* m stays. */
861		break;
862
863	case ICMP6_ROUTER_RENUMBERING:
864		if (code != ICMP6_ROUTER_RENUMBERING_COMMAND &&
865		    code != ICMP6_ROUTER_RENUMBERING_RESULT)
866			goto badcode;
867		if (icmp6len < sizeof(struct icmp6_router_renum))
868			goto badlen;
869		break;
870
871	default:
872		nd6log(LOG_DEBUG,
873		    "unknown type %d(src=%s, dst=%s, ifid=%d)\n",
874		    icmp6->icmp6_type,
875		    IN6_PRINT(ip6buf, &ip6->ip6_src),
876		    IN6_PRINT(ip6buf2, &ip6->ip6_dst),
877		    rcvif ? rcvif->if_index : 0);
878		if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) {
879			/* ICMPv6 error: MUST deliver it by spec... */
880			code = PRC_NCMDS;
881			/* deliver */
882		} else {
883			/* ICMPv6 informational: MUST not deliver */
884			break;
885		}
886	deliver:
887		if (icmp6_notify_error(m, off, icmp6len, code)) {
888			/* In this case, m should've been freed. */
889			m_put_rcvif_psref(rcvif, &psref);
890			return;
891		}
892		break;
893
894	badcode:
895		ICMP6_STATINC(ICMP6_STAT_BADCODE);
896		break;
897
898	badlen:
899		ICMP6_STATINC(ICMP6_STAT_BADLEN);
900		break;
901	}
902	m_put_rcvif_psref(rcvif, &psref);
903
904	/* deliver the packet to appropriate sockets */
905	icmp6_rip6_input(&m, off);
906
907	return;
908
909freeit:
910	m_put_rcvif_psref(rcvif, &psref);
911	m_freem(m);
912	return;
913}
914
915int
916icmp6_input(struct mbuf **mp, int *offp, int proto)
917{
918
919	wqinput_input(icmp6_wqinput, *mp, *offp, proto);
920
921	return IPPROTO_DONE;
922}
923
924static int
925icmp6_notify_error(struct mbuf *m, int off, int icmp6len, int code)
926{
927	struct icmp6_hdr *icmp6;
928	struct ip6_hdr *eip6;
929	u_int32_t notifymtu;
930	struct sockaddr_in6 icmp6src, icmp6dst;
931
932	if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) {
933		ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
934		goto freeit;
935	}
936	IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off,
937	    sizeof(*icmp6) + sizeof(struct ip6_hdr));
938	if (icmp6 == NULL) {
939		ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
940		return (-1);
941	}
942	eip6 = (struct ip6_hdr *)(icmp6 + 1);
943
944	/* Detect the upper level protocol */
945	{
946		void *(*ctlfunc)(int, const struct sockaddr *, void *);
947		u_int8_t nxt = eip6->ip6_nxt;
948		int eoff = off + sizeof(struct icmp6_hdr) +
949			sizeof(struct ip6_hdr);
950		struct ip6ctlparam ip6cp;
951		struct in6_addr *finaldst = NULL;
952		int icmp6type = icmp6->icmp6_type;
953		struct ip6_frag *fh;
954		struct ip6_rthdr *rth;
955		struct ifnet *rcvif;
956		int s;
957
958		while (1) { /* XXX: should avoid infinite loop explicitly? */
959			struct ip6_ext *eh;
960
961			switch (nxt) {
962			case IPPROTO_HOPOPTS:
963			case IPPROTO_DSTOPTS:
964			case IPPROTO_AH:
965				IP6_EXTHDR_GET(eh, struct ip6_ext *, m,
966				    eoff, sizeof(*eh));
967				if (eh == NULL) {
968					ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
969					return (-1);
970				}
971
972				if (nxt == IPPROTO_AH)
973					eoff += (eh->ip6e_len + 2) << 2;
974				else
975					eoff += (eh->ip6e_len + 1) << 3;
976				nxt = eh->ip6e_nxt;
977				break;
978			case IPPROTO_ROUTING:
979				/* Ignore the option. */
980				IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m,
981				    eoff, sizeof(*rth));
982				if (rth == NULL) {
983					ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
984					return (-1);
985				}
986
987				eoff += (rth->ip6r_len + 1) << 3;
988				nxt = rth->ip6r_nxt;
989				break;
990			case IPPROTO_FRAGMENT:
991				IP6_EXTHDR_GET(fh, struct ip6_frag *, m,
992				    eoff, sizeof(*fh));
993				if (fh == NULL) {
994					ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
995					return (-1);
996				}
997				/*
998				 * Data after a fragment header is meaningless
999				 * unless it is the first fragment, but
1000				 * we'll go to the notify label for path MTU
1001				 * discovery.
1002				 */
1003				if (fh->ip6f_offlg & IP6F_OFF_MASK)
1004					goto notify;
1005
1006				eoff += sizeof(struct ip6_frag);
1007				nxt = fh->ip6f_nxt;
1008				break;
1009			default:
1010				/*
1011				 * This case includes ESP and the No Next
1012				 * Header.  In such cases going to the notify
1013				 * label does not have any meaning
1014				 * (i.e. ctlfunc will be NULL), but we go
1015				 * anyway since we might have to update
1016				 * path MTU information.
1017				 */
1018				goto notify;
1019			}
1020		}
1021	  notify:
1022		IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off,
1023		    sizeof(*icmp6) + sizeof(struct ip6_hdr));
1024		if (icmp6 == NULL) {
1025			ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
1026			return (-1);
1027		}
1028
1029		/*
1030		 * retrieve parameters from the inner IPv6 header, and convert
1031		 * them into sockaddr structures.
1032		 * XXX: there is no guarantee that the source or destination
1033		 * addresses of the inner packet are in the same scope zone as
1034		 * the addresses of the icmp packet.  But there is no other
1035		 * way to determine the zone.
1036		 */
1037		eip6 = (struct ip6_hdr *)(icmp6 + 1);
1038
1039		rcvif = m_get_rcvif(m, &s);
1040		if (__predict_false(rcvif == NULL))
1041			goto freeit;
1042		sockaddr_in6_init(&icmp6dst,
1043		    (finaldst == NULL) ? &eip6->ip6_dst : finaldst, 0, 0, 0);
1044		if (in6_setscope(&icmp6dst.sin6_addr, rcvif, NULL)) {
1045			m_put_rcvif(rcvif, &s);
1046			goto freeit;
1047		}
1048		sockaddr_in6_init(&icmp6src, &eip6->ip6_src, 0, 0, 0);
1049		if (in6_setscope(&icmp6src.sin6_addr, rcvif, NULL)) {
1050			m_put_rcvif(rcvif, &s);
1051			goto freeit;
1052		}
1053		m_put_rcvif(rcvif, &s);
1054
1055		icmp6src.sin6_flowinfo =
1056			(eip6->ip6_flow & IPV6_FLOWLABEL_MASK);
1057
1058		if (finaldst == NULL)
1059			finaldst = &eip6->ip6_dst;
1060		ip6cp.ip6c_m = m;
1061		ip6cp.ip6c_icmp6 = icmp6;
1062		ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1);
1063		ip6cp.ip6c_off = eoff;
1064		ip6cp.ip6c_finaldst = finaldst;
1065		ip6cp.ip6c_src = &icmp6src;
1066		ip6cp.ip6c_nxt = nxt;
1067
1068		if (icmp6type == ICMP6_PACKET_TOO_BIG) {
1069			notifymtu = ntohl(icmp6->icmp6_mtu);
1070			ip6cp.ip6c_cmdarg = (void *)&notifymtu;
1071		}
1072
1073		ctlfunc = inet6sw[ip6_protox[nxt]].pr_ctlinput;
1074		if (ctlfunc) {
1075			(void)(*ctlfunc)(code, sin6tosa(&icmp6dst), &ip6cp);
1076		}
1077	}
1078	return (0);
1079
1080freeit:
1081	m_freem(m);
1082	return (-1);
1083}
1084
1085void
1086icmp6_mtudisc_update(struct ip6ctlparam *ip6cp, int validated)
1087{
1088	unsigned long rtcount;
1089	struct icmp6_mtudisc_callback *mc;
1090	struct in6_addr *dst = ip6cp->ip6c_finaldst;
1091	struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6;
1092	struct mbuf *m = ip6cp->ip6c_m;	/* will be necessary for scope issue */
1093	u_int mtu = ntohl(icmp6->icmp6_mtu);
1094	struct rtentry *rt = NULL;
1095	struct sockaddr_in6 sin6;
1096	struct ifnet *rcvif;
1097	int s;
1098
1099	/*
1100	 * The MTU should not be less than the minimal IPv6 MTU except for the
1101	 * hack in ip6_output/ip6_setpmtu where we always include a frag header.
1102	 * In that one case, the MTU might be less than 1280.
1103	 */
1104	if (__predict_false(mtu < IPV6_MMTU - sizeof(struct ip6_frag))) {
1105		/* is the mtu even sane? */
1106		if (mtu < sizeof(struct ip6_hdr) + sizeof(struct ip6_frag) + 8)
1107			return;
1108		if (!validated)
1109			return;
1110		mtu = IPV6_MMTU - sizeof(struct ip6_frag);
1111	}
1112
1113	/*
1114	 * allow non-validated cases if memory is plenty, to make traffic
1115	 * from non-connected pcb happy.
1116	 */
1117	mutex_enter(&icmp6_mtx);
1118	rtcount = rt_timer_count(icmp6_mtudisc_timeout_q);
1119	if (validated) {
1120		if (0 <= icmp6_mtudisc_hiwat && rtcount > icmp6_mtudisc_hiwat) {
1121			mutex_exit(&icmp6_mtx);
1122			return;
1123		} else if (0 <= icmp6_mtudisc_lowat &&
1124		    rtcount > icmp6_mtudisc_lowat) {
1125			/*
1126			 * XXX nuke a victim, install the new one.
1127			 */
1128		}
1129	} else {
1130		if (0 <= icmp6_mtudisc_lowat && rtcount > icmp6_mtudisc_lowat) {
1131			mutex_exit(&icmp6_mtx);
1132			return;
1133		}
1134	}
1135	mutex_exit(&icmp6_mtx);
1136
1137	memset(&sin6, 0, sizeof(sin6));
1138	sin6.sin6_family = PF_INET6;
1139	sin6.sin6_len = sizeof(struct sockaddr_in6);
1140	sin6.sin6_addr = *dst;
1141	rcvif = m_get_rcvif(m, &s);
1142	if (__predict_false(rcvif == NULL))
1143		return;
1144	if (in6_setscope(&sin6.sin6_addr, rcvif, NULL)) {
1145		m_put_rcvif(rcvif, &s);
1146		return;
1147	}
1148	m_put_rcvif(rcvif, &s);
1149
1150	rt = icmp6_mtudisc_clone(sin6tosa(&sin6));
1151
1152	if (rt && (rt->rt_flags & RTF_HOST) &&
1153	    !(rt->rt_rmx.rmx_locks & RTV_MTU) &&
1154	    (rt->rt_rmx.rmx_mtu > mtu || rt->rt_rmx.rmx_mtu == 0)) {
1155		if (mtu < rt->rt_ifp->if_mtu) {
1156			ICMP6_STATINC(ICMP6_STAT_PMTUCHG);
1157			rt->rt_rmx.rmx_mtu = mtu;
1158		}
1159	}
1160	if (rt) {
1161		rt_unref(rt);
1162	}
1163
1164	/*
1165	 * Notify protocols that the MTU for this destination
1166	 * has changed.
1167	 */
1168	mutex_enter(&icmp6_mtx);
1169	for (mc = LIST_FIRST(&icmp6_mtudisc_callbacks); mc != NULL;
1170	     mc = LIST_NEXT(mc, mc_list))
1171		(*mc->mc_func)(&sin6.sin6_addr);
1172	mutex_exit(&icmp6_mtx);
1173}
1174
1175/*
1176 * Process a Node Information Query packet, based on
1177 * draft-ietf-ipngwg-icmp-name-lookups-07.
1178 *
1179 * Spec incompatibilities:
1180 * - IPv6 Subject address handling
1181 * - IPv4 Subject address handling support missing
1182 * - Proxy reply (answer even if it's not for me)
1183 * - joins NI group address at in6_ifattach() time only, does not cope
1184 *   with hostname changes by sethostname(3)
1185 */
1186static struct mbuf *
1187ni6_input(struct mbuf *m, int off)
1188{
1189	struct icmp6_nodeinfo *ni6, *nni6;
1190	struct mbuf *n = NULL;
1191	u_int16_t qtype;
1192	int subjlen;
1193	int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo);
1194	struct ni_reply_fqdn *fqdn;
1195	int addrs;		/* for NI_QTYPE_NODEADDR */
1196	struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */
1197	struct sockaddr_in6 sin6; /* ip6_dst */
1198	struct in6_addr in6_subj; /* subject address */
1199	struct ip6_hdr *ip6;
1200	int oldfqdn = 0;	/* if 1, return pascal string (03 draft) */
1201	char *subj = NULL;
1202	struct ifnet *rcvif;
1203	int s, ss;
1204	struct ifaddr *ifa;
1205	struct psref psref;
1206
1207	ip6 = mtod(m, struct ip6_hdr *);
1208	IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6));
1209	if (ni6 == NULL) {
1210		/* m is already reclaimed */
1211		return NULL;
1212	}
1213	KASSERT((m->m_flags & M_PKTHDR) != 0);
1214
1215	/*
1216	 * Validate IPv6 destination address.
1217	 *
1218	 * The Responder must discard the Query without further processing
1219	 * unless it is one of the Responder's unicast or anycast addresses, or
1220	 * a link-local scope multicast address which the Responder has joined.
1221	 * [icmp-name-lookups-07, Section 4.]
1222	 */
1223	sockaddr_in6_init(&sin6, &ip6->ip6_dst, 0, 0, 0);
1224	/* XXX scopeid */
1225	ss = pserialize_read_enter();
1226	ifa = ifa_ifwithaddr(sin6tosa(&sin6));
1227	if (ifa != NULL) {
1228		; /* unicast/anycast, fine */
1229	} else if (IN6_IS_ADDR_MC_LINKLOCAL(&sin6.sin6_addr)) {
1230		; /* link-local multicast, fine */
1231	} else {
1232		pserialize_read_exit(ss);
1233		goto bad;
1234	}
1235	pserialize_read_exit(ss);
1236
1237	/* validate query Subject field. */
1238	qtype = ntohs(ni6->ni_qtype);
1239	subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo);
1240	switch (qtype) {
1241	case NI_QTYPE_NOOP:
1242	case NI_QTYPE_SUPTYPES:
1243		/* 07 draft */
1244		if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0)
1245			break;
1246		/* FALLTHROUGH */
1247	case NI_QTYPE_FQDN:
1248	case NI_QTYPE_NODEADDR:
1249	case NI_QTYPE_IPV4ADDR:
1250		switch (ni6->ni_code) {
1251		case ICMP6_NI_SUBJ_IPV6:
1252#if ICMP6_NI_SUBJ_IPV6 != 0
1253		case 0:
1254#endif
1255			/*
1256			 * backward compatibility - try to accept 03 draft
1257			 * format, where no Subject is present.
1258			 */
1259			if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 &&
1260			    subjlen == 0) {
1261				oldfqdn++;
1262				break;
1263			}
1264#if ICMP6_NI_SUBJ_IPV6 != 0
1265			if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6)
1266				goto bad;
1267#endif
1268
1269			if (subjlen != sizeof(sin6.sin6_addr))
1270				goto bad;
1271
1272			/*
1273			 * Validate Subject address.
1274			 *
1275			 * Not sure what exactly "address belongs to the node"
1276			 * means in the spec, is it just unicast, or what?
1277			 *
1278			 * At this moment we consider Subject address as
1279			 * "belong to the node" if the Subject address equals
1280			 * to the IPv6 destination address; validation for
1281			 * IPv6 destination address should have done enough
1282			 * check for us.
1283			 *
1284			 * We do not do proxy at this moment.
1285			 */
1286			/* m_pulldown instead of copy? */
1287			m_copydata(m, off + sizeof(struct icmp6_nodeinfo),
1288			    subjlen, (void *)&in6_subj);
1289			rcvif = m_get_rcvif(m, &s);
1290			if (__predict_false(rcvif == NULL))
1291				goto bad;
1292			if (in6_setscope(&in6_subj, rcvif, NULL)) {
1293				m_put_rcvif(rcvif, &s);
1294				goto bad;
1295			}
1296			m_put_rcvif(rcvif, &s);
1297
1298			subj = (char *)&in6_subj;
1299			if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &in6_subj))
1300				break;
1301
1302			/*
1303			 * XXX if we are to allow other cases, we should really
1304			 * be careful about scope here.
1305			 * basically, we should disallow queries toward IPv6
1306			 * destination X with subject Y, if scope(X) > scope(Y).
1307			 * if we allow scope(X) > scope(Y), it will result in
1308			 * information leakage across scope boundary.
1309			 */
1310			goto bad;
1311
1312		case ICMP6_NI_SUBJ_FQDN:
1313			/*
1314			 * Validate Subject name with gethostname(3).
1315			 *
1316			 * The behavior may need some debate, since:
1317			 * - we are not sure if the node has FQDN as
1318			 *   hostname (returned by gethostname(3)).
1319			 * - the code does wildcard match for truncated names.
1320			 *   however, we are not sure if we want to perform
1321			 *   wildcard match, if gethostname(3) side has
1322			 *   truncated hostname.
1323			 */
1324			n = ni6_nametodns(hostname, hostnamelen, 0);
1325			if (!n || n->m_next || n->m_len == 0)
1326				goto bad;
1327			IP6_EXTHDR_GET(subj, char *, m,
1328			    off + sizeof(struct icmp6_nodeinfo), subjlen);
1329			if (subj == NULL)
1330				goto bad;
1331			if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *),
1332			    n->m_len)) {
1333				goto bad;
1334			}
1335			m_freem(n);
1336			n = NULL;
1337			break;
1338
1339		case ICMP6_NI_SUBJ_IPV4:	/* XXX: to be implemented? */
1340		default:
1341			goto bad;
1342		}
1343		break;
1344	}
1345
1346	/* refuse based on configuration.  XXX ICMP6_NI_REFUSED? */
1347	switch (qtype) {
1348	case NI_QTYPE_FQDN:
1349		if ((icmp6_nodeinfo & 1) == 0)
1350			goto bad;
1351		break;
1352	case NI_QTYPE_NODEADDR:
1353	case NI_QTYPE_IPV4ADDR:
1354		if ((icmp6_nodeinfo & 2) == 0)
1355			goto bad;
1356		break;
1357	}
1358
1359	/* guess reply length */
1360	switch (qtype) {
1361	case NI_QTYPE_NOOP:
1362		break;		/* no reply data */
1363	case NI_QTYPE_SUPTYPES:
1364		replylen += sizeof(u_int32_t);
1365		break;
1366	case NI_QTYPE_FQDN:
1367		/* will append an mbuf */
1368		replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen);
1369		break;
1370	case NI_QTYPE_NODEADDR:
1371		addrs = ni6_addrs(ni6, &ifp, subj, &psref);
1372		replylen += addrs *
1373		    (sizeof(struct in6_addr) + sizeof(u_int32_t));
1374		if (replylen > MCLBYTES)
1375			replylen = MCLBYTES; /* XXX: will truncate pkt later */
1376		break;
1377	case NI_QTYPE_IPV4ADDR:
1378		/* unsupported - should respond with unknown Qtype? */
1379		goto bad;
1380	default:
1381		/*
1382		 * XXX: We must return a reply with the ICMP6 code
1383		 * `unknown Qtype' in this case.  However we regard the case
1384		 * as an FQDN query for backward compatibility.
1385		 * Older versions set a random value to this field,
1386		 * so it rarely varies in the defined qtypes.
1387		 * But the mechanism is not reliable...
1388		 * maybe we should obsolete older versions.
1389		 */
1390		qtype = NI_QTYPE_FQDN;
1391		/* will append an mbuf */
1392		replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen);
1393		oldfqdn++;
1394		break;
1395	}
1396
1397	/* allocate an mbuf to reply. */
1398	MGETHDR(n, M_DONTWAIT, m->m_type);
1399	if (n == NULL) {
1400		goto bad;
1401	}
1402	m_move_pkthdr(n, m);
1403	if (replylen > MHLEN) {
1404		if (replylen > MCLBYTES) {
1405			/*
1406			 * XXX: should we try to allocate more? But MCLBYTES
1407			 * is probably much larger than IPV6_MMTU...
1408			 */
1409			goto bad;
1410		}
1411		MCLGET(n, M_DONTWAIT);
1412		if ((n->m_flags & M_EXT) == 0) {
1413			goto bad;
1414		}
1415	}
1416	n->m_pkthdr.len = n->m_len = replylen;
1417
1418	/* copy mbuf header and IPv6 + Node Information base headers */
1419	bcopy(mtod(m, void *), mtod(n, void *), sizeof(struct ip6_hdr));
1420	nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1);
1421	bcopy((void *)ni6, (void *)nni6, sizeof(struct icmp6_nodeinfo));
1422
1423	/* qtype dependent procedure */
1424	switch (qtype) {
1425	case NI_QTYPE_NOOP:
1426		nni6->ni_code = ICMP6_NI_SUCCESS;
1427		nni6->ni_flags = 0;
1428		break;
1429	case NI_QTYPE_SUPTYPES:
1430	{
1431		u_int32_t v;
1432		nni6->ni_code = ICMP6_NI_SUCCESS;
1433		nni6->ni_flags = htons(0x0000);	/* raw bitmap */
1434		/* supports NOOP, SUPTYPES, FQDN, and NODEADDR */
1435		v = (u_int32_t)htonl(0x0000000f);
1436		memcpy(nni6 + 1, &v, sizeof(u_int32_t));
1437		break;
1438	}
1439	case NI_QTYPE_FQDN:
1440		nni6->ni_code = ICMP6_NI_SUCCESS;
1441		fqdn = (struct ni_reply_fqdn *)(mtod(n, char *) +
1442		    sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo));
1443		nni6->ni_flags = 0; /* XXX: meaningless TTL */
1444		fqdn->ni_fqdn_ttl = 0;	/* ditto. */
1445		/*
1446		 * XXX do we really have FQDN in variable "hostname"?
1447		 */
1448		n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn);
1449		if (n->m_next == NULL)
1450			goto bad;
1451		/* XXX we assume that n->m_next is not a chain */
1452		if (n->m_next->m_next != NULL)
1453			goto bad;
1454		n->m_pkthdr.len += n->m_next->m_len;
1455		break;
1456	case NI_QTYPE_NODEADDR:
1457	{
1458		int lenlim, copied;
1459
1460		nni6->ni_code = ICMP6_NI_SUCCESS;
1461		n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
1462		    sizeof(struct icmp6_nodeinfo);
1463		lenlim = M_TRAILINGSPACE(n);
1464		copied = ni6_store_addrs(ni6, nni6, ifp, lenlim);
1465		if_put(ifp, &psref);
1466		ifp = NULL;
1467		/* update mbuf length */
1468		n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
1469		    sizeof(struct icmp6_nodeinfo) + copied;
1470		break;
1471	}
1472	default:
1473		panic("%s: impossible", __func__);
1474		break;
1475	}
1476
1477	nni6->ni_type = ICMP6_NI_REPLY;
1478	m_freem(m);
1479	return n;
1480
1481bad:
1482	if_put(ifp, &psref);
1483	m_freem(m);
1484	if (n)
1485		m_freem(n);
1486	return NULL;
1487}
1488
1489#define isupper(x) ('A' <= (x) && (x) <= 'Z')
1490#define isalpha(x) (('A' <= (x) && (x) <= 'Z') || ('a' <= (x) && (x) <= 'z'))
1491#define isalnum(x) (isalpha(x) || ('0' <= (x) && (x) <= '9'))
1492#define tolower(x) (isupper(x) ? (x) + 'a' - 'A' : (x))
1493
1494/*
1495 * make a mbuf with DNS-encoded string.  no compression support.
1496 *
1497 * XXX names with less than 2 dots (like "foo" or "foo.section") will be
1498 * treated as truncated name (two \0 at the end).  this is a wild guess.
1499 *
1500 * old - return pascal string if non-zero
1501 */
1502static struct mbuf *
1503ni6_nametodns(const char *name, int namelen, int old)
1504{
1505	struct mbuf *m;
1506	char *cp, *ep;
1507	const char *p, *q;
1508	int i, len, nterm;
1509
1510	if (old)
1511		len = namelen + 1;
1512	else
1513		len = MCLBYTES;
1514
1515	/* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */
1516	MGET(m, M_DONTWAIT, MT_DATA);
1517	if (m && len > MLEN) {
1518		MCLGET(m, M_DONTWAIT);
1519		if ((m->m_flags & M_EXT) == 0)
1520			goto fail;
1521	}
1522	if (!m)
1523		goto fail;
1524	m->m_next = NULL;
1525
1526	if (old) {
1527		m->m_len = len;
1528		*mtod(m, char *) = namelen;
1529		memcpy(mtod(m, char *) + 1, name, namelen);
1530		return m;
1531	} else {
1532		m->m_len = 0;
1533		cp = mtod(m, char *);
1534		ep = mtod(m, char *) + M_TRAILINGSPACE(m);
1535
1536		/* if not certain about my name, return empty buffer */
1537		if (namelen == 0)
1538			return m;
1539
1540		/*
1541		 * guess if it looks like shortened hostname, or FQDN.
1542		 * shortened hostname needs two trailing "\0".
1543		 */
1544		i = 0;
1545		for (p = name; p < name + namelen; p++) {
1546			if (*p == '.')
1547				i++;
1548		}
1549		if (i < 2)
1550			nterm = 2;
1551		else
1552			nterm = 1;
1553
1554		p = name;
1555		while (cp < ep && p < name + namelen) {
1556			i = 0;
1557			for (q = p; q < name + namelen && *q && *q != '.'; q++)
1558				i++;
1559			/* result does not fit into mbuf */
1560			if (cp + i + 1 >= ep)
1561				goto fail;
1562			/*
1563			 * DNS label length restriction, RFC1035 page 8.
1564			 * "i == 0" case is included here to avoid returning
1565			 * 0-length label on "foo..bar".
1566			 */
1567			if (i <= 0 || i >= 64)
1568				goto fail;
1569			*cp++ = i;
1570			if (!isalpha(p[0]) || !isalnum(p[i - 1]))
1571				goto fail;
1572			while (i > 0) {
1573				if (!isalnum(*p) && *p != '-')
1574					goto fail;
1575				if (isupper(*p)) {
1576					*cp++ = tolower(*p);
1577					p++;
1578				} else
1579					*cp++ = *p++;
1580				i--;
1581			}
1582			p = q;
1583			if (p < name + namelen && *p == '.')
1584				p++;
1585		}
1586		/* termination */
1587		if (cp + nterm >= ep)
1588			goto fail;
1589		while (nterm-- > 0)
1590			*cp++ = '\0';
1591		m->m_len = cp - mtod(m, char *);
1592		return m;
1593	}
1594
1595	panic("should not reach here");
1596	/* NOTREACHED */
1597
1598fail:
1599	if (m)
1600		m_freem(m);
1601	return NULL;
1602}
1603
1604/*
1605 * check if two DNS-encoded string matches.  takes care of truncated
1606 * form (with \0\0 at the end).  no compression support.
1607 * XXX upper/lowercase match (see RFC2065)
1608 */
1609static int
1610ni6_dnsmatch(const char *a, int alen, const char *b, int blen)
1611{
1612	const char *a0, *b0;
1613	int l;
1614
1615	/* simplest case - need validation? */
1616	if (alen == blen && memcmp(a, b, alen) == 0)
1617		return 1;
1618
1619	a0 = a;
1620	b0 = b;
1621
1622	/* termination is mandatory */
1623	if (alen < 2 || blen < 2)
1624		return 0;
1625	if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0')
1626		return 0;
1627	alen--;
1628	blen--;
1629
1630	while (a - a0 < alen && b - b0 < blen) {
1631		if (a - a0 + 1 > alen || b - b0 + 1 > blen)
1632			return 0;
1633
1634		if ((signed char)a[0] < 0 || (signed char)b[0] < 0)
1635			return 0;
1636		/* we don't support compression yet */
1637		if (a[0] >= 64 || b[0] >= 64)
1638			return 0;
1639
1640		/* truncated case */
1641		if (a[0] == 0 && a - a0 == alen - 1)
1642			return 1;
1643		if (b[0] == 0 && b - b0 == blen - 1)
1644			return 1;
1645		if (a[0] == 0 || b[0] == 0)
1646			return 0;
1647
1648		if (a[0] != b[0])
1649			return 0;
1650		l = a[0];
1651		if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen)
1652			return 0;
1653		if (memcmp(a + 1, b + 1, l) != 0)
1654			return 0;
1655
1656		a += 1 + l;
1657		b += 1 + l;
1658	}
1659
1660	if (a - a0 == alen && b - b0 == blen)
1661		return 1;
1662	else
1663		return 0;
1664}
1665
1666/*
1667 * calculate the number of addresses to be returned in the node info reply.
1668 */
1669static int
1670ni6_addrs(struct icmp6_nodeinfo *ni6, struct ifnet **ifpp, char *subj,
1671    struct psref *psref)
1672{
1673	struct ifnet *ifp;
1674	struct in6_ifaddr *ia6;
1675	struct ifaddr *ifa;
1676	struct sockaddr_in6 *subj_ip6 = NULL; /* XXX pedant */
1677	int addrs = 0, addrsofif, iffound = 0;
1678	int niflags = ni6->ni_flags;
1679	int s;
1680
1681	if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) {
1682		switch (ni6->ni_code) {
1683		case ICMP6_NI_SUBJ_IPV6:
1684			if (subj == NULL) /* must be impossible... */
1685				return 0;
1686			subj_ip6 = (struct sockaddr_in6 *)subj;
1687			break;
1688		default:
1689			/*
1690			 * XXX: we only support IPv6 subject address for
1691			 * this Qtype.
1692			 */
1693			return 0;
1694		}
1695	}
1696
1697	s = pserialize_read_enter();
1698	IFNET_READER_FOREACH(ifp) {
1699		addrsofif = 0;
1700		IFADDR_READER_FOREACH(ifa, ifp) {
1701			if (ifa->ifa_addr->sa_family != AF_INET6)
1702				continue;
1703			ia6 = (struct in6_ifaddr *)ifa;
1704
1705			if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 &&
1706			    IN6_ARE_ADDR_EQUAL(&subj_ip6->sin6_addr,
1707			     &ia6->ia_addr.sin6_addr))
1708				iffound = 1;
1709
1710			/*
1711			 * IPv4-mapped addresses can only be returned by a
1712			 * Node Information proxy, since they represent
1713			 * addresses of IPv4-only nodes, which perforce do
1714			 * not implement this protocol.
1715			 * [icmp-name-lookups-07, Section 5.4]
1716			 * So we don't support NI_NODEADDR_FLAG_COMPAT in
1717			 * this function at this moment.
1718			 */
1719
1720			/* What do we have to do about ::1? */
1721			switch (in6_addrscope(&ia6->ia_addr.sin6_addr)) {
1722			case IPV6_ADDR_SCOPE_LINKLOCAL:
1723				if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0)
1724					continue;
1725				break;
1726			case IPV6_ADDR_SCOPE_SITELOCAL:
1727				if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0)
1728					continue;
1729				break;
1730			case IPV6_ADDR_SCOPE_GLOBAL:
1731				if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0)
1732					continue;
1733				break;
1734			default:
1735				continue;
1736			}
1737
1738			/*
1739			 * check if anycast is okay.
1740			 * XXX: just experimental.  not in the spec.
1741			 */
1742			if ((ia6->ia6_flags & IN6_IFF_ANYCAST) != 0 &&
1743			    (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0)
1744				continue; /* we need only unicast addresses */
1745
1746			addrsofif++; /* count the address */
1747		}
1748		if (iffound) {
1749			if_acquire(ifp, psref);
1750			pserialize_read_exit(s);
1751			*ifpp = ifp;
1752			return addrsofif;
1753		}
1754
1755		addrs += addrsofif;
1756	}
1757	pserialize_read_exit(s);
1758
1759	return addrs;
1760}
1761
1762static int
1763ni6_store_addrs(struct icmp6_nodeinfo *ni6,
1764	struct icmp6_nodeinfo *nni6, struct ifnet *ifp0,
1765	int resid)
1766{
1767	struct ifnet *ifp;
1768	struct in6_ifaddr *ia6;
1769	struct ifaddr *ifa;
1770	struct ifnet *ifp_dep = NULL;
1771	int copied = 0, allow_deprecated = 0;
1772	u_char *cp = (u_char *)(nni6 + 1);
1773	int niflags = ni6->ni_flags;
1774	u_int32_t ltime;
1775	int s;
1776
1777	if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL))
1778		return 0;	/* needless to copy */
1779
1780	s = pserialize_read_enter();
1781	ifp = ifp0 ? ifp0 : IFNET_READER_FIRST();
1782again:
1783
1784	for (; ifp; ifp = IFNET_READER_NEXT(ifp))
1785	{
1786		IFADDR_READER_FOREACH(ifa, ifp) {
1787			if (ifa->ifa_addr->sa_family != AF_INET6)
1788				continue;
1789			ia6 = (struct in6_ifaddr *)ifa;
1790
1791			if ((ia6->ia6_flags & IN6_IFF_DEPRECATED) != 0 &&
1792			    allow_deprecated == 0) {
1793				/*
1794				 * prefererred address should be put before
1795				 * deprecated addresses.
1796				 */
1797
1798				/* record the interface for later search */
1799				if (ifp_dep == NULL)
1800					ifp_dep = ifp;
1801
1802				continue;
1803			}
1804			else if ((ia6->ia6_flags & IN6_IFF_DEPRECATED) == 0 &&
1805				 allow_deprecated != 0)
1806				continue; /* we now collect deprecated addrs */
1807
1808			/* What do we have to do about ::1? */
1809			switch (in6_addrscope(&ia6->ia_addr.sin6_addr)) {
1810			case IPV6_ADDR_SCOPE_LINKLOCAL:
1811				if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0)
1812					continue;
1813				break;
1814			case IPV6_ADDR_SCOPE_SITELOCAL:
1815				if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0)
1816					continue;
1817				break;
1818			case IPV6_ADDR_SCOPE_GLOBAL:
1819				if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0)
1820					continue;
1821				break;
1822			default:
1823				continue;
1824			}
1825
1826			/*
1827			 * check if anycast is okay.
1828			 * XXX: just experimental.  not in the spec.
1829			 */
1830			if ((ia6->ia6_flags & IN6_IFF_ANYCAST) != 0 &&
1831			    (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0)
1832				continue;
1833
1834			/* now we can copy the address */
1835			if (resid < sizeof(struct in6_addr) +
1836			    sizeof(u_int32_t)) {
1837				/*
1838				 * We give up much more copy.
1839				 * Set the truncate flag and return.
1840				 */
1841				nni6->ni_flags |= NI_NODEADDR_FLAG_TRUNCATE;
1842				goto out;
1843			}
1844
1845			/*
1846			 * Set the TTL of the address.
1847			 * The TTL value should be one of the following
1848			 * according to the specification:
1849			 *
1850			 * 1. The remaining lifetime of a DHCP lease on the
1851			 *    address, or
1852			 * 2. The remaining Valid Lifetime of a prefix from
1853			 *    which the address was derived through Stateless
1854			 *    Autoconfiguration.
1855			 *
1856			 * Note that we currently do not support stateful
1857			 * address configuration by DHCPv6, so the former
1858			 * case can't happen.
1859			 *
1860			 * TTL must be 2^31 > TTL >= 0.
1861			 */
1862			if (ia6->ia6_lifetime.ia6t_expire == 0)
1863				ltime = ND6_INFINITE_LIFETIME;
1864			else {
1865				if (ia6->ia6_lifetime.ia6t_expire >
1866				    time_uptime)
1867					ltime = ia6->ia6_lifetime.ia6t_expire -
1868					    time_uptime;
1869				else
1870					ltime = 0;
1871			}
1872			if (ltime > 0x7fffffff)
1873				ltime = 0x7fffffff;
1874			ltime = htonl(ltime);
1875
1876			memcpy(cp, &ltime, sizeof(u_int32_t));
1877			cp += sizeof(u_int32_t);
1878
1879			/* copy the address itself */
1880			bcopy(&ia6->ia_addr.sin6_addr, cp,
1881			      sizeof(struct in6_addr));
1882			in6_clearscope((struct in6_addr *)cp); /* XXX */
1883			cp += sizeof(struct in6_addr);
1884
1885			resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t));
1886			copied += (sizeof(struct in6_addr) + sizeof(u_int32_t));
1887		}
1888		if (ifp0)	/* we need search only on the specified IF */
1889			break;
1890	}
1891
1892	if (allow_deprecated == 0 && ifp_dep != NULL) {
1893		ifp = ifp_dep;
1894		allow_deprecated = 1;
1895
1896		goto again;
1897	}
1898out:
1899	pserialize_read_exit(s);
1900	return copied;
1901}
1902
1903/*
1904 * XXX almost dup'ed code with rip6_input.
1905 */
1906static int
1907icmp6_rip6_input(struct mbuf **mp, int off)
1908{
1909	struct mbuf *m = *mp;
1910	struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1911	struct inpcb_hdr *inph;
1912	struct in6pcb *in6p;
1913	struct in6pcb *last = NULL;
1914	struct sockaddr_in6 rip6src;
1915	struct icmp6_hdr *icmp6;
1916	struct mbuf *n, *opts = NULL;
1917
1918	IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6));
1919	if (icmp6 == NULL) {
1920		/* m is already reclaimed */
1921		return IPPROTO_DONE;
1922	}
1923
1924	/*
1925	 * XXX: the address may have embedded scope zone ID, which should be
1926	 * hidden from applications.
1927	 */
1928	sockaddr_in6_init(&rip6src, &ip6->ip6_src, 0, 0, 0);
1929	if (sa6_recoverscope(&rip6src)) {
1930		m_freem(m);
1931		return IPPROTO_DONE;
1932	}
1933
1934	TAILQ_FOREACH(inph, &raw6cbtable.inpt_queue, inph_queue) {
1935		in6p = (struct in6pcb *)inph;
1936		if (in6p->in6p_af != AF_INET6)
1937			continue;
1938		if (in6p->in6p_ip6.ip6_nxt != IPPROTO_ICMPV6)
1939			continue;
1940		if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) &&
1941		    !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst))
1942			continue;
1943		if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) &&
1944		    !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src))
1945			continue;
1946		if (in6p->in6p_icmp6filt &&
1947		    ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type,
1948		    in6p->in6p_icmp6filt))
1949			continue;
1950
1951		if (last == NULL) {
1952			;
1953		}
1954#ifdef IPSEC
1955		else if (ipsec_used && ipsec_in_reject(m, last)) {
1956			/* do not inject data into pcb */
1957		}
1958#endif
1959		else if ((n = m_copypacket(m, M_DONTWAIT)) != NULL) {
1960			if (last->in6p_flags & IN6P_CONTROLOPTS)
1961				ip6_savecontrol(last, &opts, ip6, n);
1962			/* strip intermediate headers */
1963			m_adj(n, off);
1964			if (sbappendaddr(&last->in6p_socket->so_rcv,
1965			    sin6tosa(&rip6src), n, opts) == 0) {
1966				soroverflow(last->in6p_socket);
1967				m_freem(n);
1968				if (opts)
1969					m_freem(opts);
1970			} else {
1971				sorwakeup(last->in6p_socket);
1972			}
1973			opts = NULL;
1974		}
1975
1976		last = in6p;
1977	}
1978
1979#ifdef IPSEC
1980	if (ipsec_used && last && ipsec_in_reject(m, last)) {
1981		m_freem(m);
1982		IP6_STATDEC(IP6_STAT_DELIVERED);
1983		/* do not inject data into pcb */
1984	} else
1985#endif
1986	if (last) {
1987		if (last->in6p_flags & IN6P_CONTROLOPTS)
1988			ip6_savecontrol(last, &opts, ip6, m);
1989		/* strip intermediate headers */
1990		m_adj(m, off);
1991		if (sbappendaddr(&last->in6p_socket->so_rcv,
1992		    sin6tosa(&rip6src), m, opts) == 0) {
1993			soroverflow(last->in6p_socket);
1994			m_freem(m);
1995			if (opts)
1996				m_freem(opts);
1997		} else {
1998			sorwakeup(last->in6p_socket);
1999		}
2000	} else {
2001		m_freem(m);
2002		IP6_STATDEC(IP6_STAT_DELIVERED);
2003	}
2004	return IPPROTO_DONE;
2005}
2006
2007/*
2008 * Reflect the ip6 packet back to the source.
2009 * OFF points to the icmp6 header, counted from the top of the mbuf.
2010 *
2011 * Note: RFC 1885 required that an echo reply should be truncated if it
2012 * did not fit in with (return) path MTU, and KAME code supported the
2013 * behavior.  However, as a clarification after the RFC, this limitation
2014 * was removed in a revised version of the spec, RFC 2463.  We had kept the
2015 * old behavior, with a (non-default) ifdef block, while the new version of
2016 * the spec was an internet-draft status, and even after the new RFC was
2017 * published.  But it would rather make sense to clean the obsoleted part
2018 * up, and to make the code simpler at this stage.
2019 */
2020static void
2021icmp6_reflect(struct mbuf *m, size_t off)
2022{
2023	struct ip6_hdr *ip6;
2024	struct icmp6_hdr *icmp6;
2025	const struct in6_ifaddr *ia;
2026	const struct ip6aux *ip6a;
2027	int plen;
2028	int type, code;
2029	struct ifnet *outif = NULL;
2030	struct in6_addr origdst;
2031	struct ifnet *rcvif;
2032	int s;
2033	bool ip6_src_filled = false;
2034
2035	/* too short to reflect */
2036	if (off < sizeof(struct ip6_hdr)) {
2037		nd6log(LOG_DEBUG,
2038		    "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n",
2039		    (u_long)off, (u_long)sizeof(struct ip6_hdr),
2040		    __FILE__, __LINE__);
2041		goto bad;
2042	}
2043
2044	/*
2045	 * If there are extra headers between IPv6 and ICMPv6, strip
2046	 * off that header first.
2047	 */
2048	CTASSERT(sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) <= MHLEN);
2049	if (off > sizeof(struct ip6_hdr)) {
2050		size_t l;
2051		struct ip6_hdr nip6;
2052
2053		l = off - sizeof(struct ip6_hdr);
2054		m_copydata(m, 0, sizeof(nip6), (void *)&nip6);
2055		m_adj(m, l);
2056		l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
2057		if (m->m_len < l) {
2058			if ((m = m_pullup(m, l)) == NULL)
2059				return;
2060		}
2061		memcpy(mtod(m, void *), (void *)&nip6, sizeof(nip6));
2062	} else {
2063		size_t l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
2064		if (m->m_len < l) {
2065			if ((m = m_pullup(m, l)) == NULL)
2066				return;
2067		}
2068	}
2069
2070	plen = m->m_pkthdr.len - sizeof(struct ip6_hdr);
2071	ip6 = mtod(m, struct ip6_hdr *);
2072	ip6->ip6_nxt = IPPROTO_ICMPV6;
2073	icmp6 = (struct icmp6_hdr *)(ip6 + 1);
2074	type = icmp6->icmp6_type; /* keep type for statistics */
2075	code = icmp6->icmp6_code; /* ditto. */
2076
2077	origdst = ip6->ip6_dst;
2078	/*
2079	 * ip6_input() drops a packet if its src is multicast.
2080	 * So, the src is never multicast.
2081	 */
2082	ip6->ip6_dst = ip6->ip6_src;
2083
2084	/*
2085	 * If the incoming packet was addressed directly to us (i.e. unicast),
2086	 * use dst as the src for the reply.
2087	 * The IN6_IFF_NOTREADY case should be VERY rare, but is possible
2088	 * (for example) when we encounter an error while forwarding procedure
2089	 * destined to a duplicated address of ours.
2090	 * Note that ip6_getdstifaddr() may fail if we are in an error handling
2091	 * procedure of an outgoing packet of our own, in which case we need
2092	 * to search in the ifaddr list.
2093	 */
2094	if (IN6_IS_ADDR_MULTICAST(&origdst)) {
2095		;
2096	} else if ((ip6a = ip6_getdstifaddr(m)) != NULL) {
2097		if ((ip6a->ip6a_flags &
2098		     (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)) == 0) {
2099			ip6->ip6_src = ip6a->ip6a_src;
2100			ip6_src_filled = true;
2101		}
2102	} else {
2103		union {
2104			struct sockaddr_in6 sin6;
2105			struct sockaddr sa;
2106		} u;
2107		int _s;
2108		struct ifaddr *ifa;
2109
2110		sockaddr_in6_init(&u.sin6, &origdst, 0, 0, 0);
2111
2112		_s = pserialize_read_enter();
2113		ifa = ifa_ifwithaddr(&u.sa);
2114
2115		if (ifa != NULL) {
2116			ia = ifatoia6(ifa);
2117			if ((ia->ia6_flags &
2118				 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)) == 0) {
2119				ip6->ip6_src = ia->ia_addr.sin6_addr;
2120				ip6_src_filled = true;
2121			}
2122		}
2123		pserialize_read_exit(_s);
2124	}
2125
2126	if (!ip6_src_filled) {
2127		int e;
2128		struct sockaddr_in6 sin6;
2129		struct route ro;
2130
2131		/*
2132		 * This case matches to multicasts, our anycast, or unicasts
2133		 * that we do not own.  Select a source address based on the
2134		 * source address of the erroneous packet.
2135		 */
2136		/* zone ID should be embedded */
2137		sockaddr_in6_init(&sin6, &ip6->ip6_dst, 0, 0, 0);
2138
2139		memset(&ro, 0, sizeof(ro));
2140		e = in6_selectsrc(&sin6, NULL, NULL, &ro, NULL, NULL, NULL,
2141		    &ip6->ip6_src);
2142		rtcache_free(&ro);
2143		if (e != 0) {
2144			char ip6buf[INET6_ADDRSTRLEN];
2145			nd6log(LOG_DEBUG,
2146			    "source can't be determined: "
2147			    "dst=%s, error=%d\n",
2148			    IN6_PRINT(ip6buf, &sin6.sin6_addr), e);
2149			goto bad;
2150		}
2151	}
2152
2153	ip6->ip6_flow = 0;
2154	ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
2155	ip6->ip6_vfc |= IPV6_VERSION;
2156	ip6->ip6_nxt = IPPROTO_ICMPV6;
2157	rcvif = m_get_rcvif(m, &s);
2158	if (rcvif) {
2159		/* XXX: This may not be the outgoing interface */
2160		ip6->ip6_hlim = ND_IFINFO(rcvif)->chlim;
2161	} else {
2162		ip6->ip6_hlim = ip6_defhlim;
2163	}
2164	m_put_rcvif(rcvif, &s);
2165
2166	m->m_pkthdr.csum_flags = 0;
2167	icmp6->icmp6_cksum = 0;
2168	icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6,
2169	    sizeof(struct ip6_hdr), plen);
2170
2171	/*
2172	 * XXX option handling
2173	 */
2174
2175	m->m_flags &= ~(M_BCAST|M_MCAST);
2176
2177	/*
2178	 * To avoid a "too big" situation at an intermediate router
2179	 * and the path MTU discovery process, specify the IPV6_MINMTU flag.
2180	 * Note that only echo and node information replies are affected,
2181	 * since the length of ICMP6 errors is limited to the minimum MTU.
2182	 */
2183	if (ip6_output(m, NULL, NULL, IPV6_MINMTU, NULL, NULL, &outif) != 0 &&
2184	    outif)
2185		icmp6_ifstat_inc(outif, ifs6_out_error);
2186	if (outif)
2187		icmp6_ifoutstat_inc(outif, type, code);
2188
2189	return;
2190
2191 bad:
2192	m_freem(m);
2193	return;
2194}
2195
2196static const char *
2197icmp6_redirect_diag(char *buf, size_t buflen, struct in6_addr *src6,
2198    struct in6_addr *dst6,  struct in6_addr *tgt6)
2199{
2200	char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
2201	char ip6buft[INET6_ADDRSTRLEN];
2202
2203	snprintf(buf, buflen, "(src=%s dst=%s tgt=%s)",
2204	    IN6_PRINT(ip6bufs, src6), IN6_PRINT(ip6bufd, dst6),
2205	    IN6_PRINT(ip6buft, tgt6));
2206	return buf;
2207}
2208
2209static void
2210icmp6_redirect_input(struct mbuf *m, int off)
2211{
2212	struct ifnet *ifp;
2213	struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
2214	struct nd_redirect *nd_rd;
2215	int icmp6len = m->m_pkthdr.len - off;
2216	char *lladdr = NULL;
2217	int lladdrlen = 0;
2218	struct rtentry *rt = NULL;
2219	int is_router;
2220	int is_onlink;
2221	struct in6_addr src6 = ip6->ip6_src;
2222	struct in6_addr redtgt6;
2223	struct in6_addr reddst6;
2224	union nd_opts ndopts;
2225	struct psref psref;
2226	char ip6buf[INET6_ADDRSTRLEN];
2227	char diagbuf[256];
2228
2229	ifp = m_get_rcvif_psref(m, &psref);
2230	if (ifp == NULL)
2231		goto freeit;
2232
2233	/* XXX if we are router, we don't update route by icmp6 redirect */
2234	if (ip6_forwarding)
2235		goto freeit;
2236	if (!icmp6_rediraccept)
2237		goto freeit;
2238
2239	IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len);
2240	if (nd_rd == NULL) {
2241		ICMP6_STATINC(ICMP6_STAT_TOOSHORT);
2242		m_put_rcvif_psref(ifp, &psref);
2243		return;
2244	}
2245	redtgt6 = nd_rd->nd_rd_target;
2246	reddst6 = nd_rd->nd_rd_dst;
2247
2248	if (in6_setscope(&redtgt6, ifp, NULL) ||
2249	    in6_setscope(&reddst6, ifp, NULL)) {
2250		goto freeit;
2251	}
2252
2253	/* validation */
2254	if (!IN6_IS_ADDR_LINKLOCAL(&src6)) {
2255		nd6log(LOG_ERR,
2256		    "ICMP6 redirect sent from %s rejected; "
2257		    "must be from linklocal\n", IN6_PRINT(ip6buf, &src6));
2258		goto bad;
2259	}
2260	if (ip6->ip6_hlim != 255) {
2261		nd6log(LOG_ERR,
2262		    "ICMP6 redirect sent from %s rejected; "
2263		    "hlim=%d (must be 255)\n",
2264		    IN6_PRINT(ip6buf, &src6), ip6->ip6_hlim);
2265		goto bad;
2266	}
2267
2268    {
2269	/* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */
2270	struct sockaddr_in6 sin6;
2271	struct in6_addr *gw6;
2272
2273	sockaddr_in6_init(&sin6, &reddst6, 0, 0, 0);
2274	rt = rtalloc1(sin6tosa(&sin6), 0);
2275	if (rt) {
2276		if (rt->rt_gateway == NULL ||
2277		    rt->rt_gateway->sa_family != AF_INET6) {
2278			nd6log(LOG_ERR,
2279			    "ICMP6 redirect rejected; no route "
2280			    "with inet6 gateway found for redirect dst: %s\n",
2281			    icmp6_redirect_diag(diagbuf, sizeof(diagbuf),
2282			    &src6, &reddst6, &redtgt6));
2283			rt_unref(rt);
2284			goto bad;
2285		}
2286
2287		gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr);
2288		if (memcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) {
2289			nd6log(LOG_ERR,
2290			    "ICMP6 redirect rejected; "
2291			    "not equal to gw-for-src=%s (must be same): %s\n",
2292			    IN6_PRINT(ip6buf, gw6),
2293			    icmp6_redirect_diag(diagbuf, sizeof(diagbuf),
2294			    &src6, &reddst6, &redtgt6));
2295			rt_unref(rt);
2296			goto bad;
2297		}
2298	} else {
2299		nd6log(LOG_ERR, "ICMP6 redirect rejected; "
2300		    "no route found for redirect dst: %s\n",
2301		    icmp6_redirect_diag(diagbuf, sizeof(diagbuf),
2302		    &src6, &reddst6, &redtgt6));
2303		goto bad;
2304	}
2305	rt_unref(rt);
2306	rt = NULL;
2307    }
2308
2309	if (IN6_IS_ADDR_MULTICAST(&reddst6)) {
2310		nd6log(LOG_ERR, "ICMP6 redirect rejected; "
2311		    "redirect dst must be unicast: %s\n",
2312		    icmp6_redirect_diag(diagbuf, sizeof(diagbuf),
2313		    &src6, &reddst6, &redtgt6));
2314		goto bad;
2315	}
2316
2317	is_router = is_onlink = 0;
2318	if (IN6_IS_ADDR_LINKLOCAL(&redtgt6))
2319		is_router = 1;	/* router case */
2320	if (memcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0)
2321		is_onlink = 1;	/* on-link destination case */
2322	if (!is_router && !is_onlink) {
2323		nd6log(LOG_ERR, "ICMP6 redirect rejected; "
2324		    "neither router case nor onlink case: %s\n",
2325		    icmp6_redirect_diag(diagbuf, sizeof(diagbuf),
2326		    &src6, &reddst6, &redtgt6));
2327		goto bad;
2328	}
2329	/* validation passed */
2330
2331	icmp6len -= sizeof(*nd_rd);
2332	nd6_option_init(nd_rd + 1, icmp6len, &ndopts);
2333	if (nd6_options(&ndopts) < 0) {
2334		nd6log(LOG_INFO, "invalid ND option, rejected: %s\n",
2335		    icmp6_redirect_diag(diagbuf, sizeof(diagbuf),
2336		    &src6, &reddst6, &redtgt6));
2337		/* nd6_options have incremented stats */
2338		goto freeit;
2339	}
2340
2341	if (ndopts.nd_opts_tgt_lladdr) {
2342		lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
2343		lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
2344	}
2345
2346	if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
2347		nd6log(LOG_INFO, "lladdrlen mismatch for %s "
2348		    "(if %d, icmp6 packet %d): %s\n",
2349		    IN6_PRINT(ip6buf, &redtgt6),
2350		    ifp->if_addrlen, lladdrlen - 2,
2351		    icmp6_redirect_diag(diagbuf, sizeof(diagbuf),
2352		    &src6, &reddst6, &redtgt6));
2353		goto bad;
2354	}
2355
2356	/* RFC 2461 8.3 */
2357	nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT,
2358	    is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER);
2359
2360	m_put_rcvif_psref(ifp, &psref);
2361	ifp = NULL;
2362
2363	if (!is_onlink) {	/* better router case.  perform rtredirect. */
2364		/* perform rtredirect */
2365		struct sockaddr_in6 sdst;
2366		struct sockaddr_in6 sgw;
2367		struct sockaddr_in6 ssrc;
2368		unsigned long rtcount;
2369		struct rtentry *newrt = NULL;
2370
2371		/*
2372		 * do not install redirect route, if the number of entries
2373		 * is too much (> hiwat).  note that, the node (= host) will
2374		 * work just fine even if we do not install redirect route
2375		 * (there will be additional hops, though).
2376		 */
2377		mutex_enter(&icmp6_mtx);
2378		rtcount = rt_timer_count(icmp6_redirect_timeout_q);
2379		if (0 <= ip6_maxdynroutes && rtcount >= ip6_maxdynroutes) {
2380			mutex_exit(&icmp6_mtx);
2381			goto freeit;
2382		}
2383		if (0 <= icmp6_redirect_hiwat && rtcount > icmp6_redirect_hiwat) {
2384			mutex_exit(&icmp6_mtx);
2385			goto freeit;
2386		} else if (0 <= icmp6_redirect_lowat &&
2387		    rtcount > icmp6_redirect_lowat) {
2388			/*
2389			 * XXX nuke a victim, install the new one.
2390			 */
2391		}
2392
2393		memset(&sdst, 0, sizeof(sdst));
2394		memset(&sgw, 0, sizeof(sgw));
2395		memset(&ssrc, 0, sizeof(ssrc));
2396		sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6;
2397		sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len =
2398		    sizeof(struct sockaddr_in6);
2399		bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr));
2400		bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr));
2401		bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr));
2402		rtredirect(sin6tosa(&sdst), sin6tosa(&sgw), NULL,
2403		    RTF_GATEWAY | RTF_HOST, sin6tosa(&ssrc), &newrt);
2404
2405		if (newrt) {
2406			(void)rt_timer_add(newrt, icmp6_redirect_timeout,
2407			    icmp6_redirect_timeout_q);
2408			rt_unref(newrt);
2409		}
2410		mutex_exit(&icmp6_mtx);
2411	}
2412	/* finally update cached route in each socket via pfctlinput */
2413	{
2414		struct sockaddr_in6 sdst;
2415
2416		sockaddr_in6_init(&sdst, &reddst6, 0, 0, 0);
2417		pfctlinput(PRC_REDIRECT_HOST, sin6tosa(&sdst));
2418#if defined(IPSEC)
2419		if (ipsec_used)
2420			key_sa_routechange(sin6tosa(&sdst));
2421#endif
2422	}
2423
2424freeit:
2425	if (ifp != NULL)
2426		m_put_rcvif_psref(ifp, &psref);
2427	m_freem(m);
2428	return;
2429
2430bad:
2431	m_put_rcvif_psref(ifp, &psref);
2432	ICMP6_STATINC(ICMP6_STAT_BADREDIRECT);
2433	m_freem(m);
2434}
2435
2436void
2437icmp6_redirect_output(struct mbuf *m0, struct rtentry *rt)
2438{
2439	struct ifnet *ifp;	/* my outgoing interface */
2440	struct in6_addr *ifp_ll6;
2441	struct in6_addr *nexthop;
2442	struct ip6_hdr *sip6;	/* m0 as struct ip6_hdr */
2443	struct mbuf *m = NULL;	/* newly allocated one */
2444	struct ip6_hdr *ip6;	/* m as struct ip6_hdr */
2445	struct nd_redirect *nd_rd;
2446	size_t maxlen;
2447	u_char *p;
2448	struct sockaddr_in6 src_sa;
2449
2450	icmp6_errcount(ICMP6_STAT_OUTERRHIST, ND_REDIRECT, 0);
2451
2452	/* if we are not router, we don't send icmp6 redirect */
2453	if (!ip6_forwarding)
2454		goto fail;
2455
2456	/* sanity check */
2457	KASSERT(m0 != NULL);
2458	KASSERT(rt != NULL);
2459
2460	ifp = rt->rt_ifp;
2461
2462	/*
2463	 * Address check:
2464	 *  the source address must identify a neighbor, and
2465	 *  the destination address must not be a multicast address
2466	 *  [RFC 2461, sec 8.2]
2467	 */
2468	sip6 = mtod(m0, struct ip6_hdr *);
2469	sockaddr_in6_init(&src_sa, &sip6->ip6_src, 0, 0, 0);
2470	if (nd6_is_addr_neighbor(&src_sa, ifp) == 0)
2471		goto fail;
2472	if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst))
2473		goto fail;	/* what should we do here? */
2474
2475	/* rate limit */
2476	if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0))
2477		goto fail;
2478
2479	/*
2480	 * Since we are going to append up to 1280 bytes (= IPV6_MMTU),
2481	 * we almost always ask for an mbuf cluster for simplicity.
2482	 * (MHLEN < IPV6_MMTU is almost always true)
2483	 */
2484	MGETHDR(m, M_DONTWAIT, MT_HEADER);
2485	if (m && IPV6_MMTU >= MHLEN) {
2486#if IPV6_MMTU >= MCLBYTES
2487		MEXTMALLOC(m, IPV6_MMTU, M_NOWAIT);
2488#else
2489		MCLGET(m, M_DONTWAIT);
2490#endif
2491	}
2492
2493	if (!m)
2494		goto fail;
2495	m_reset_rcvif(m);
2496	m->m_len = 0;
2497	maxlen = M_TRAILINGSPACE(m);
2498	maxlen = uimin(IPV6_MMTU, maxlen);
2499
2500	/* just for safety */
2501	if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct nd_redirect) +
2502	    ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) {
2503		goto fail;
2504	}
2505
2506	{
2507		/* get ip6 linklocal address for ifp(my outgoing interface). */
2508		struct in6_ifaddr *ia;
2509		int s = pserialize_read_enter();
2510		if ((ia = in6ifa_ifpforlinklocal(ifp,
2511						 IN6_IFF_NOTREADY|
2512						 IN6_IFF_ANYCAST)) == NULL) {
2513			pserialize_read_exit(s);
2514			goto fail;
2515		}
2516		ifp_ll6 = &ia->ia_addr.sin6_addr;
2517		pserialize_read_exit(s);
2518	}
2519
2520	/* get ip6 linklocal address for the router. */
2521	if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) {
2522		struct sockaddr_in6 *sin6;
2523		sin6 = (struct sockaddr_in6 *)rt->rt_gateway;
2524		nexthop = &sin6->sin6_addr;
2525		if (!IN6_IS_ADDR_LINKLOCAL(nexthop))
2526			nexthop = NULL;
2527	} else
2528		nexthop = NULL;
2529
2530	/* ip6 */
2531	ip6 = mtod(m, struct ip6_hdr *);
2532	ip6->ip6_flow = 0;
2533	ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
2534	ip6->ip6_vfc |= IPV6_VERSION;
2535	/* ip6->ip6_plen will be set later */
2536	ip6->ip6_nxt = IPPROTO_ICMPV6;
2537	ip6->ip6_hlim = 255;
2538	/* ip6->ip6_src must be linklocal addr for my outgoing if. */
2539	bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr));
2540	bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr));
2541
2542	/* ND Redirect */
2543	nd_rd = (struct nd_redirect *)(ip6 + 1);
2544	nd_rd->nd_rd_type = ND_REDIRECT;
2545	nd_rd->nd_rd_code = 0;
2546	nd_rd->nd_rd_reserved = 0;
2547	if (rt->rt_flags & RTF_GATEWAY) {
2548		/*
2549		 * nd_rd->nd_rd_target must be a link-local address in
2550		 * better router cases.
2551		 */
2552		if (!nexthop)
2553			goto fail;
2554		bcopy(nexthop, &nd_rd->nd_rd_target,
2555		      sizeof(nd_rd->nd_rd_target));
2556		bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst,
2557		      sizeof(nd_rd->nd_rd_dst));
2558	} else {
2559		/* make sure redtgt == reddst */
2560		nexthop = &sip6->ip6_dst;
2561		bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target,
2562		      sizeof(nd_rd->nd_rd_target));
2563		bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst,
2564		      sizeof(nd_rd->nd_rd_dst));
2565	}
2566
2567	p = (u_char *)(nd_rd + 1);
2568
2569	{
2570		/* target lladdr option */
2571		struct llentry *ln = NULL;
2572		int len, pad;
2573		struct nd_opt_hdr *nd_opt;
2574		char *lladdr;
2575
2576		ln = nd6_lookup(nexthop, ifp, false);
2577		if (ln == NULL)
2578			goto nolladdropt;
2579		len = sizeof(*nd_opt) + ifp->if_addrlen;
2580		len = (len + 7) & ~7;	/* round by 8 */
2581		pad = len - (sizeof(*nd_opt) + ifp->if_addrlen);
2582
2583		/* safety check */
2584		if (len + (p - (u_char *)ip6) > maxlen) {
2585			LLE_RUNLOCK(ln);
2586			goto nolladdropt;
2587		}
2588
2589		if (ln->la_flags & LLE_VALID) {
2590			nd_opt = (struct nd_opt_hdr *)p;
2591			nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
2592			nd_opt->nd_opt_len = len >> 3;
2593			lladdr = (char *)(nd_opt + 1);
2594			memcpy(lladdr, &ln->ll_addr, ifp->if_addrlen);
2595			memset(lladdr + ifp->if_addrlen, 0, pad);
2596			p += len;
2597		}
2598		LLE_RUNLOCK(ln);
2599	}
2600nolladdropt:
2601
2602	m->m_pkthdr.len = m->m_len = p - (u_char *)ip6;
2603
2604	/* just to be safe */
2605	if (m0->m_flags & M_DECRYPTED)
2606		goto noredhdropt;
2607	if (p - (u_char *)ip6 > maxlen)
2608		goto noredhdropt;
2609
2610	{
2611		/* redirected header option */
2612		int len;
2613		struct nd_opt_rd_hdr *nd_opt_rh;
2614
2615		/*
2616		 * compute the maximum size for icmp6 redirect header option.
2617		 * XXX room for auth header?
2618		 */
2619		len = maxlen - (p - (u_char *)ip6);
2620		len &= ~7;
2621
2622		if (len < sizeof(*nd_opt_rh)) {
2623			goto noredhdropt;
2624		}
2625
2626		/*
2627		 * Redirected header option spec (RFC2461 4.6.3) talks nothing
2628		 * about padding/truncate rule for the original IP packet.
2629		 * From the discussion on IPv6imp in Feb 1999,
2630		 * the consensus was:
2631		 * - "attach as much as possible" is the goal
2632		 * - pad if not aligned (original size can be guessed by
2633		 *   original ip6 header)
2634		 * Following code adds the padding if it is simple enough,
2635		 * and truncates if not.
2636		 */
2637		if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) {
2638			/* not enough room, truncate */
2639			m_adj(m0, (len - sizeof(*nd_opt_rh)) -
2640			    m0->m_pkthdr.len);
2641		} else {
2642			/*
2643			 * enough room, truncate if not aligned.
2644			 * we don't pad here for simplicity.
2645			 */
2646			int extra;
2647
2648			extra = m0->m_pkthdr.len % 8;
2649			if (extra) {
2650				/* truncate */
2651				m_adj(m0, -extra);
2652			}
2653			len = m0->m_pkthdr.len + sizeof(*nd_opt_rh);
2654		}
2655
2656		nd_opt_rh = (struct nd_opt_rd_hdr *)p;
2657		memset(nd_opt_rh, 0, sizeof(*nd_opt_rh));
2658		nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER;
2659		nd_opt_rh->nd_opt_rh_len = len >> 3;
2660		p += sizeof(*nd_opt_rh);
2661		m->m_pkthdr.len = m->m_len = p - (u_char *)ip6;
2662
2663		/* connect m0 to m */
2664		m->m_pkthdr.len += m0->m_pkthdr.len;
2665		m_cat(m, m0);
2666		m0 = NULL;
2667	}
2668noredhdropt:
2669	if (m0) {
2670		m_freem(m0);
2671		m0 = NULL;
2672	}
2673
2674	/* XXX: clear embedded link IDs in the inner header */
2675	in6_clearscope(&sip6->ip6_src);
2676	in6_clearscope(&sip6->ip6_dst);
2677	in6_clearscope(&nd_rd->nd_rd_target);
2678	in6_clearscope(&nd_rd->nd_rd_dst);
2679
2680	ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
2681
2682	nd_rd->nd_rd_cksum = 0;
2683	nd_rd->nd_rd_cksum =
2684	    in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), ntohs(ip6->ip6_plen));
2685
2686	/* send the packet to outside... */
2687	if (ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL) != 0)
2688		icmp6_ifstat_inc(ifp, ifs6_out_error);
2689
2690	icmp6_ifstat_inc(ifp, ifs6_out_msg);
2691	icmp6_ifstat_inc(ifp, ifs6_out_redirect);
2692	ICMP6_STATINC(ICMP6_STAT_OUTHIST + ND_REDIRECT);
2693
2694	return;
2695
2696fail:
2697	if (m)
2698		m_freem(m);
2699	if (m0)
2700		m_freem(m0);
2701}
2702
2703/*
2704 * ICMPv6 socket option processing.
2705 */
2706int
2707icmp6_ctloutput(int op, struct socket *so, struct sockopt *sopt)
2708{
2709	int error = 0;
2710	struct in6pcb *in6p = sotoin6pcb(so);
2711
2712	if (sopt->sopt_level != IPPROTO_ICMPV6)
2713		return rip6_ctloutput(op, so, sopt);
2714
2715	switch (op) {
2716	case PRCO_SETOPT:
2717		switch (sopt->sopt_name) {
2718		case ICMP6_FILTER:
2719		    {
2720			struct icmp6_filter fil;
2721
2722			error = sockopt_get(sopt, &fil, sizeof(fil));
2723			if (error)
2724				break;
2725			memcpy(in6p->in6p_icmp6filt, &fil,
2726			    sizeof(struct icmp6_filter));
2727			error = 0;
2728			break;
2729		    }
2730
2731		default:
2732			error = ENOPROTOOPT;
2733			break;
2734		}
2735		break;
2736
2737	case PRCO_GETOPT:
2738		switch (sopt->sopt_name) {
2739		case ICMP6_FILTER:
2740		    {
2741			if (in6p->in6p_icmp6filt == NULL) {
2742				error = EINVAL;
2743				break;
2744			}
2745			error = sockopt_set(sopt, in6p->in6p_icmp6filt,
2746			    sizeof(struct icmp6_filter));
2747			break;
2748		    }
2749
2750		default:
2751			error = ENOPROTOOPT;
2752			break;
2753		}
2754		break;
2755	}
2756
2757	return error;
2758}
2759
2760/*
2761 * Perform rate limit check.
2762 * Returns 0 if it is okay to send the icmp6 packet.
2763 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate
2764 * limitation.
2765 *
2766 * XXX per-destination/type check necessary?
2767 */
2768static int
2769icmp6_ratelimit(
2770	const struct in6_addr *dst,	/* not used at this moment */
2771	const int type,		/* not used at this moment */
2772	const int code)		/* not used at this moment */
2773{
2774	int ret;
2775
2776	ret = 0;	/* okay to send */
2777
2778	/* PPS limit */
2779	if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count,
2780	    icmp6errppslim)) {
2781		/* The packet is subject to rate limit */
2782		ret++;
2783	}
2784
2785	return ret;
2786}
2787
2788static struct rtentry *
2789icmp6_mtudisc_clone(struct sockaddr *dst)
2790{
2791	struct rtentry *rt;
2792	int    error;
2793
2794	rt = rtalloc1(dst, 1);
2795	if (rt == NULL)
2796		return NULL;
2797
2798	/* If we didn't get a host route, allocate one */
2799	if ((rt->rt_flags & RTF_HOST) == 0) {
2800		struct rtentry *nrt;
2801
2802		error = rtrequest(RTM_ADD, dst, rt->rt_gateway, NULL,
2803		    RTF_GATEWAY | RTF_HOST | RTF_DYNAMIC, &nrt);
2804		if (error) {
2805			rt_unref(rt);
2806			return NULL;
2807		}
2808		nrt->rt_rmx = rt->rt_rmx;
2809		rt_unref(rt);
2810		rt = nrt;
2811	}
2812
2813	mutex_enter(&icmp6_mtx);
2814	error = rt_timer_add(rt, icmp6_mtudisc_timeout,
2815			icmp6_mtudisc_timeout_q);
2816	mutex_exit(&icmp6_mtx);
2817
2818	if (error) {
2819		rt_unref(rt);
2820		return NULL;
2821	}
2822
2823	return rt;	/* caller need to call rtfree() */
2824}
2825
2826static void
2827icmp6_mtudisc_timeout(struct rtentry *rt, struct rttimer *r)
2828{
2829	struct rtentry *retrt;
2830
2831	KASSERT(rt != NULL);
2832	rt_assert_referenced(rt);
2833
2834	if ((rt->rt_flags & (RTF_DYNAMIC | RTF_HOST)) ==
2835	    (RTF_DYNAMIC | RTF_HOST)) {
2836		rtrequest(RTM_DELETE, rt_getkey(rt),
2837		    rt->rt_gateway, rt_mask(rt), rt->rt_flags, &retrt);
2838		rt_unref(rt);
2839		rt_free(retrt);
2840	} else {
2841		if (!(rt->rt_rmx.rmx_locks & RTV_MTU))
2842			rt->rt_rmx.rmx_mtu = 0;
2843	}
2844}
2845
2846static void
2847icmp6_redirect_timeout(struct rtentry *rt, struct rttimer *r)
2848{
2849	struct rtentry *retrt;
2850
2851	KASSERT(rt != NULL);
2852	rt_assert_referenced(rt);
2853
2854	if ((rt->rt_flags & (RTF_GATEWAY | RTF_DYNAMIC | RTF_HOST)) ==
2855	    (RTF_GATEWAY | RTF_DYNAMIC | RTF_HOST)) {
2856		rtrequest(RTM_DELETE, rt_getkey(rt),
2857		    rt->rt_gateway, rt_mask(rt), rt->rt_flags, &retrt);
2858		rt_unref(rt);
2859		rt_free(retrt);
2860	}
2861}
2862
2863#ifdef COMPAT_90
2864/*
2865 * sysctl helper routine for the net.inet6.icmp6.nd6 nodes.  silly?
2866 */
2867static int
2868sysctl_net_inet6_icmp6_nd6(SYSCTLFN_ARGS)
2869{
2870	(void)&name;
2871	(void)&l;
2872	(void)&oname;
2873
2874	if (namelen != 0)
2875		return (EINVAL);
2876
2877	return (nd6_sysctl(rnode->sysctl_num, oldp, oldlenp,
2878	    /*XXXUNCONST*/
2879	    __UNCONST(newp), newlen));
2880}
2881#endif
2882
2883static int
2884sysctl_net_inet6_icmp6_stats(SYSCTLFN_ARGS)
2885{
2886
2887	return (NETSTAT_SYSCTL(icmp6stat_percpu, ICMP6_NSTATS));
2888}
2889
2890static int
2891sysctl_net_inet6_icmp6_redirtimeout(SYSCTLFN_ARGS)
2892{
2893	int error, tmp;
2894	struct sysctlnode node;
2895
2896	mutex_enter(&icmp6_mtx);
2897
2898	node = *rnode;
2899	node.sysctl_data = &tmp;
2900	tmp = icmp6_redirtimeout;
2901	error = sysctl_lookup(SYSCTLFN_CALL(&node));
2902	if (error || newp == NULL)
2903		goto out;
2904	if (tmp < 0) {
2905		error = EINVAL;
2906		goto out;
2907	}
2908	icmp6_redirtimeout = tmp;
2909
2910	if (icmp6_redirect_timeout_q != NULL) {
2911		if (icmp6_redirtimeout == 0) {
2912			rt_timer_queue_destroy(icmp6_redirect_timeout_q);
2913		} else {
2914			rt_timer_queue_change(icmp6_redirect_timeout_q,
2915			    icmp6_redirtimeout);
2916		}
2917	} else if (icmp6_redirtimeout > 0) {
2918		icmp6_redirect_timeout_q =
2919		    rt_timer_queue_create(icmp6_redirtimeout);
2920	}
2921	error = 0;
2922out:
2923	mutex_exit(&icmp6_mtx);
2924	return error;
2925}
2926
2927static void
2928sysctl_net_inet6_icmp6_setup(struct sysctllog **clog)
2929{
2930	extern int nd6_maxqueuelen; /* defined in nd6.c */
2931
2932	sysctl_createv(clog, 0, NULL, NULL,
2933		       CTLFLAG_PERMANENT,
2934		       CTLTYPE_NODE, "inet6", NULL,
2935		       NULL, 0, NULL, 0,
2936		       CTL_NET, PF_INET6, CTL_EOL);
2937	sysctl_createv(clog, 0, NULL, NULL,
2938		       CTLFLAG_PERMANENT,
2939		       CTLTYPE_NODE, "icmp6",
2940		       SYSCTL_DESCR("ICMPv6 related settings"),
2941		       NULL, 0, NULL, 0,
2942		       CTL_NET, PF_INET6, IPPROTO_ICMPV6, CTL_EOL);
2943
2944	sysctl_createv(clog, 0, NULL, NULL,
2945		       CTLFLAG_PERMANENT,
2946		       CTLTYPE_STRUCT, "stats",
2947		       SYSCTL_DESCR("ICMPv6 transmission statistics"),
2948		       sysctl_net_inet6_icmp6_stats, 0, NULL, 0,
2949		       CTL_NET, PF_INET6, IPPROTO_ICMPV6,
2950		       ICMPV6CTL_STATS, CTL_EOL);
2951	sysctl_createv(clog, 0, NULL, NULL,
2952		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
2953		       CTLTYPE_INT, "rediraccept",
2954		       SYSCTL_DESCR("Accept and process redirect messages"),
2955		       NULL, 0, &icmp6_rediraccept, 0,
2956		       CTL_NET, PF_INET6, IPPROTO_ICMPV6,
2957		       ICMPV6CTL_REDIRACCEPT, CTL_EOL);
2958	sysctl_createv(clog, 0, NULL, NULL,
2959		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
2960		       CTLTYPE_INT, "redirtimeout",
2961		       SYSCTL_DESCR("Redirect generated route lifetime"),
2962		       sysctl_net_inet6_icmp6_redirtimeout, 0,
2963		       &icmp6_redirtimeout, 0,
2964		       CTL_NET, PF_INET6, IPPROTO_ICMPV6,
2965		       ICMPV6CTL_REDIRTIMEOUT, CTL_EOL);
2966#if 0 /* obsoleted */
2967	sysctl_createv(clog, 0, NULL, NULL,
2968		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
2969		       CTLTYPE_INT, "errratelimit", NULL,
2970		       NULL, 0, &icmp6_errratelimit, 0,
2971		       CTL_NET, PF_INET6, IPPROTO_ICMPV6,
2972		       ICMPV6CTL_ERRRATELIMIT, CTL_EOL);
2973#endif
2974	sysctl_createv(clog, 0, NULL, NULL,
2975		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
2976		       CTLTYPE_INT, "nd6_prune",
2977		       SYSCTL_DESCR("Neighbor discovery prune interval"),
2978		       NULL, 0, &nd6_prune, 0,
2979		       CTL_NET, PF_INET6, IPPROTO_ICMPV6,
2980		       ICMPV6CTL_ND6_PRUNE, CTL_EOL);
2981	sysctl_createv(clog, 0, NULL, NULL,
2982		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
2983		       CTLTYPE_INT, "nd6_delay",
2984		       SYSCTL_DESCR("First probe delay time"),
2985		       NULL, 0, &nd6_delay, 0,
2986		       CTL_NET, PF_INET6, IPPROTO_ICMPV6,
2987		       ICMPV6CTL_ND6_DELAY, CTL_EOL);
2988	sysctl_createv(clog, 0, NULL, NULL,
2989		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
2990		       CTLTYPE_INT, "nd6_umaxtries",
2991		       SYSCTL_DESCR("Number of unicast discovery attempts"),
2992		       NULL, 0, &nd6_umaxtries, 0,
2993		       CTL_NET, PF_INET6, IPPROTO_ICMPV6,
2994		       ICMPV6CTL_ND6_UMAXTRIES, CTL_EOL);
2995	sysctl_createv(clog, 0, NULL, NULL,
2996		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
2997		       CTLTYPE_INT, "nd6_mmaxtries",
2998		       SYSCTL_DESCR("Number of multicast discovery attempts"),
2999		       NULL, 0, &nd6_mmaxtries, 0,
3000		       CTL_NET, PF_INET6, IPPROTO_ICMPV6,
3001		       ICMPV6CTL_ND6_MMAXTRIES, CTL_EOL);
3002	sysctl_createv(clog, 0, NULL, NULL,
3003		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
3004		       CTLTYPE_INT, "nd6_useloopback",
3005		       SYSCTL_DESCR("Use loopback interface for local traffic"),
3006		       NULL, 0, &nd6_useloopback, 0,
3007		       CTL_NET, PF_INET6, IPPROTO_ICMPV6,
3008		       ICMPV6CTL_ND6_USELOOPBACK, CTL_EOL);
3009#if 0 /* obsoleted */
3010	sysctl_createv(clog, 0, NULL, NULL,
3011		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
3012		       CTLTYPE_INT, "nd6_proxyall", NULL,
3013		       NULL, 0, &nd6_proxyall, 0,
3014		       CTL_NET, PF_INET6, IPPROTO_ICMPV6,
3015		       ICMPV6CTL_ND6_PROXYALL, CTL_EOL);
3016#endif
3017	sysctl_createv(clog, 0, NULL, NULL,
3018		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
3019		       CTLTYPE_INT, "nodeinfo",
3020		       SYSCTL_DESCR("Respond to node information requests"),
3021		       NULL, 0, &icmp6_nodeinfo, 0,
3022		       CTL_NET, PF_INET6, IPPROTO_ICMPV6,
3023		       ICMPV6CTL_NODEINFO, CTL_EOL);
3024	sysctl_createv(clog, 0, NULL, NULL,
3025		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
3026		       CTLTYPE_INT, "errppslimit",
3027		       SYSCTL_DESCR("Maximum ICMP errors sent per second"),
3028		       NULL, 0, &icmp6errppslim, 0,
3029		       CTL_NET, PF_INET6, IPPROTO_ICMPV6,
3030		       ICMPV6CTL_ERRPPSLIMIT, CTL_EOL);
3031	sysctl_createv(clog, 0, NULL, NULL,
3032		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
3033		       CTLTYPE_INT, "nd6_maxnudhint",
3034		       SYSCTL_DESCR("Maximum neighbor unreachable hint count"),
3035		       NULL, 0, &nd6_maxnudhint, 0,
3036		       CTL_NET, PF_INET6, IPPROTO_ICMPV6,
3037		       ICMPV6CTL_ND6_MAXNUDHINT, CTL_EOL);
3038	sysctl_createv(clog, 0, NULL, NULL,
3039		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
3040		       CTLTYPE_INT, "mtudisc_hiwat",
3041		       SYSCTL_DESCR("Low mark on MTU Discovery route timers"),
3042		       NULL, 0, &icmp6_mtudisc_hiwat, 0,
3043		       CTL_NET, PF_INET6, IPPROTO_ICMPV6,
3044		       ICMPV6CTL_MTUDISC_HIWAT, CTL_EOL);
3045	sysctl_createv(clog, 0, NULL, NULL,
3046		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
3047		       CTLTYPE_INT, "mtudisc_lowat",
3048		       SYSCTL_DESCR("Low mark on MTU Discovery route timers"),
3049		       NULL, 0, &icmp6_mtudisc_lowat, 0,
3050		       CTL_NET, PF_INET6, IPPROTO_ICMPV6,
3051		       ICMPV6CTL_MTUDISC_LOWAT, CTL_EOL);
3052	sysctl_createv(clog, 0, NULL, NULL,
3053		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
3054		       CTLTYPE_INT, "nd6_debug",
3055		       SYSCTL_DESCR("Enable neighbor discovery debug output"),
3056		       NULL, 0, &nd6_debug, 0,
3057		       CTL_NET, PF_INET6, IPPROTO_ICMPV6,
3058		       ICMPV6CTL_ND6_DEBUG, CTL_EOL);
3059#ifdef COMPAT_90
3060	sysctl_createv(clog, 0, NULL, NULL,
3061		       CTLFLAG_PERMANENT,
3062		       CTLTYPE_STRUCT, "nd6_drlist",
3063		       SYSCTL_DESCR("Default router list"),
3064		       sysctl_net_inet6_icmp6_nd6, 0, NULL, 0,
3065		       CTL_NET, PF_INET6, IPPROTO_ICMPV6,
3066		       OICMPV6CTL_ND6_DRLIST, CTL_EOL);
3067	sysctl_createv(clog, 0, NULL, NULL,
3068		       CTLFLAG_PERMANENT,
3069		       CTLTYPE_STRUCT, "nd6_prlist",
3070		       SYSCTL_DESCR("Prefix list"),
3071		       sysctl_net_inet6_icmp6_nd6, 0, NULL, 0,
3072		       CTL_NET, PF_INET6, IPPROTO_ICMPV6,
3073		       OICMPV6CTL_ND6_PRLIST, CTL_EOL);
3074#endif
3075	sysctl_createv(clog, 0, NULL, NULL,
3076		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
3077		       CTLTYPE_INT, "maxqueuelen",
3078		       SYSCTL_DESCR("max packet queue len for a unresolved ND"),
3079		       NULL, 1, &nd6_maxqueuelen, 0,
3080		       CTL_NET, PF_INET6, IPPROTO_ICMPV6,
3081		       ICMPV6CTL_ND6_MAXQLEN, CTL_EOL);
3082}
3083
3084void
3085icmp6_statinc(u_int stat)
3086{
3087
3088	KASSERT(stat < ICMP6_NSTATS);
3089	ICMP6_STATINC(stat);
3090}
3091