xref: /freebsd/sys/netinet6/in6_proto.c (revision 4b2eaea43fec8e8792be611dea204071a10b655a)
1 /*	$FreeBSD$	*/
2 /*	$KAME: in6_proto.c,v 1.91 2001/05/27 13:28:35 itojun 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, 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. All advertising materials mentioning features or use of this software
46  *    must display the following acknowledgement:
47  *	This product includes software developed by the University of
48  *	California, Berkeley and its contributors.
49  * 4. Neither the name of the University nor the names of its contributors
50  *    may be used to endorse or promote products derived from this software
51  *    without specific prior written permission.
52  *
53  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
54  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
55  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
56  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
57  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
58  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
59  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
60  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
61  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
62  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
63  * SUCH DAMAGE.
64  *
65  *	@(#)in_proto.c	8.1 (Berkeley) 6/10/93
66  */
67 
68 #include "opt_inet.h"
69 #include "opt_inet6.h"
70 #include "opt_ipsec.h"
71 
72 #include <sys/param.h>
73 #include <sys/socket.h>
74 #include <sys/socketvar.h>
75 #include <sys/protosw.h>
76 #include <sys/kernel.h>
77 #include <sys/domain.h>
78 #include <sys/mbuf.h>
79 #include <sys/systm.h>
80 #include <sys/sysctl.h>
81 
82 #include <net/if.h>
83 #include <net/radix.h>
84 #include <net/route.h>
85 
86 #include <netinet/in.h>
87 #include <netinet/in_systm.h>
88 #include <netinet/in_var.h>
89 #include <netinet/ip_encap.h>
90 #include <netinet/ip.h>
91 #include <netinet/ip_var.h>
92 #include <netinet/ip6.h>
93 #include <netinet6/ip6_var.h>
94 #include <netinet/icmp6.h>
95 
96 #include <netinet/tcp.h>
97 #include <netinet/tcp_timer.h>
98 #include <netinet/tcp_var.h>
99 #include <netinet/udp.h>
100 #include <netinet/udp_var.h>
101 #include <netinet6/tcp6_var.h>
102 #include <netinet6/raw_ip6.h>
103 #include <netinet6/udp6_var.h>
104 #include <netinet6/pim6_var.h>
105 #include <netinet6/nd6.h>
106 #include <netinet6/in6_prefix.h>
107 
108 #ifdef IPSEC
109 #include <netinet6/ipsec.h>
110 #ifdef INET6
111 #include <netinet6/ipsec6.h>
112 #endif
113 #include <netinet6/ah.h>
114 #ifdef INET6
115 #include <netinet6/ah6.h>
116 #endif
117 #ifdef IPSEC_ESP
118 #include <netinet6/esp.h>
119 #ifdef INET6
120 #include <netinet6/esp6.h>
121 #endif
122 #endif
123 #include <netinet6/ipcomp.h>
124 #ifdef INET6
125 #include <netinet6/ipcomp6.h>
126 #endif
127 #endif /* IPSEC */
128 
129 #ifdef FAST_IPSEC
130 #include <netipsec/ipsec6.h>
131 #define	IPSEC
132 #define	IPSEC_ESP
133 #define	ah6_input	ipsec6_common_input
134 #define	esp6_input	ipsec6_common_input
135 #define	ipcomp6_input	ipsec6_common_input
136 #endif /* FAST_IPSEC */
137 
138 #include <netinet6/ip6protosw.h>
139 
140 #include <net/net_osdep.h>
141 
142 /*
143  * TCP/IP protocol family: IP6, ICMP6, UDP, TCP.
144  */
145 
146 extern	struct domain inet6domain;
147 static struct pr_usrreqs nousrreqs;
148 
149 #define PR_LISTEN	0
150 #define PR_ABRTACPTDIS	0
151 
152 struct ip6protosw inet6sw[] = {
153 { 0,		&inet6domain,	IPPROTO_IPV6,	0,
154   0,		0,		0,		0,
155   0,
156   ip6_init,	0,		frag6_slowtimo,	frag6_drain,
157   &nousrreqs,
158 },
159 { SOCK_DGRAM,	&inet6domain,	IPPROTO_UDP,	PR_ATOMIC|PR_ADDR,
160   udp6_input,	0,		udp6_ctlinput,	ip6_ctloutput,
161   0,
162   0,		0,		0,		0,
163   &udp6_usrreqs,
164 },
165 { SOCK_STREAM,	&inet6domain,	IPPROTO_TCP,	PR_CONNREQUIRED|PR_WANTRCVD|PR_LISTEN,
166   tcp6_input,	0,		tcp6_ctlinput,	tcp_ctloutput,
167   0,
168 #ifdef INET	/* don't call initialization and timeout routines twice */
169   0,		0,		0,		tcp_drain,
170 #else
171   tcp_init,	tcp_fasttimo,	tcp_slowtimo,	tcp_drain,
172 #endif
173   &tcp6_usrreqs,
174 },
175 { SOCK_RAW,	&inet6domain,	IPPROTO_RAW,	PR_ATOMIC|PR_ADDR,
176   rip6_input,	rip6_output,	rip6_ctlinput,	rip6_ctloutput,
177   0,
178   0,		0,		0,		0,
179   &rip6_usrreqs
180 },
181 { SOCK_RAW,	&inet6domain,	IPPROTO_ICMPV6,	PR_ATOMIC|PR_ADDR|PR_LASTHDR,
182   icmp6_input,	rip6_output,	rip6_ctlinput,	rip6_ctloutput,
183   0,
184   icmp6_init,	icmp6_fasttimo,	0,		0,
185   &rip6_usrreqs
186 },
187 { SOCK_RAW,	&inet6domain,	IPPROTO_DSTOPTS,PR_ATOMIC|PR_ADDR,
188   dest6_input,	0,	 	0,		0,
189   0,
190   0,		0,		0,		0,
191   &nousrreqs
192 },
193 { SOCK_RAW,	&inet6domain,	IPPROTO_ROUTING,PR_ATOMIC|PR_ADDR,
194   route6_input,	0,	 	0,		0,
195   0,
196   0,		0,		0,		0,
197   &nousrreqs
198 },
199 { SOCK_RAW,	&inet6domain,	IPPROTO_FRAGMENT,PR_ATOMIC|PR_ADDR,
200   frag6_input,	0,	 	0,		0,
201   0,
202   0,		0,		0,		0,
203   &nousrreqs
204 },
205 #ifdef IPSEC
206 { SOCK_RAW,	&inet6domain,	IPPROTO_AH,	PR_ATOMIC|PR_ADDR,
207   ah6_input,	0,		0,		0,
208   0,
209   0,		0,		0,		0,
210   &nousrreqs,
211 },
212 #ifdef IPSEC_ESP
213 { SOCK_RAW,	&inet6domain,	IPPROTO_ESP,	PR_ATOMIC|PR_ADDR,
214   esp6_input,	0,
215   esp6_ctlinput,
216   0,
217   0,
218   0,		0,		0,		0,
219   &nousrreqs,
220 },
221 #endif
222 { SOCK_RAW,	&inet6domain,	IPPROTO_IPCOMP,	PR_ATOMIC|PR_ADDR,
223   ipcomp6_input, 0,	 	0,		0,
224   0,
225   0,		0,		0,		0,
226   &nousrreqs,
227 },
228 #endif /* IPSEC */
229 #ifdef INET
230 { SOCK_RAW,	&inet6domain,	IPPROTO_IPV4,	PR_ATOMIC|PR_ADDR|PR_LASTHDR,
231   encap6_input,	rip6_output, 	0,		rip6_ctloutput,
232   0,
233   encap_init,	0,		0,		0,
234   &rip6_usrreqs
235 },
236 #endif /* INET */
237 { SOCK_RAW,	&inet6domain,	IPPROTO_IPV6,	PR_ATOMIC|PR_ADDR|PR_LASTHDR,
238   encap6_input, rip6_output,	0,		rip6_ctloutput,
239   0,
240   encap_init,	0,		0,		0,
241   &rip6_usrreqs
242 },
243 { SOCK_RAW,     &inet6domain,	IPPROTO_PIM,	PR_ATOMIC|PR_ADDR|PR_LASTHDR,
244   pim6_input,	rip6_output,	0,              rip6_ctloutput,
245   0,
246   0,            0,              0,              0,
247   &rip6_usrreqs
248 },
249 /* raw wildcard */
250 { SOCK_RAW,	&inet6domain,	0,		PR_ATOMIC|PR_ADDR,
251   rip6_input,	rip6_output,	0,		rip6_ctloutput,
252   0,
253   0,		0,		0,		0,
254   &rip6_usrreqs
255 },
256 };
257 
258 extern int in6_inithead __P((void **, int));
259 
260 struct domain inet6domain =
261     { AF_INET6, "internet6", 0, 0, 0,
262       (struct protosw *)inet6sw,
263       (struct protosw *)&inet6sw[sizeof(inet6sw)/sizeof(inet6sw[0])], 0,
264       in6_inithead,
265       offsetof(struct sockaddr_in6, sin6_addr) << 3,
266       sizeof(struct sockaddr_in6) };
267 
268 DOMAIN_SET(inet6);
269 
270 /*
271  * Internet configuration info
272  */
273 #ifndef	IPV6FORWARDING
274 #ifdef GATEWAY6
275 #define	IPV6FORWARDING	1	/* forward IP6 packets not for us */
276 #else
277 #define	IPV6FORWARDING	0	/* don't forward IP6 packets not for us */
278 #endif /* GATEWAY6 */
279 #endif /* !IPV6FORWARDING */
280 
281 #ifndef	IPV6_SENDREDIRECTS
282 #define	IPV6_SENDREDIRECTS	1
283 #endif
284 
285 int	ip6_forwarding = IPV6FORWARDING;	/* act as router? */
286 int	ip6_sendredirects = IPV6_SENDREDIRECTS;
287 int	ip6_defhlim = IPV6_DEFHLIM;
288 int	ip6_defmcasthlim = IPV6_DEFAULT_MULTICAST_HOPS;
289 int	ip6_accept_rtadv = 0;	/* "IPV6FORWARDING ? 0 : 1" is dangerous */
290 int	ip6_maxfragpackets;	/* initialized in frag6.c:frag6_init() */
291 int	ip6_log_interval = 5;
292 int	ip6_hdrnestlimit = 50;	/* appropriate? */
293 int	ip6_dad_count = 1;	/* DupAddrDetectionTransmits */
294 u_int32_t ip6_flow_seq;
295 int	ip6_auto_flowlabel = 1;
296 int	ip6_gif_hlim = 0;
297 int	ip6_use_deprecated = 1;	/* allow deprecated addr (RFC2462 5.5.4) */
298 int	ip6_rr_prune = 5;	/* router renumbering prefix
299 				 * walk list every 5 sec.    */
300 int	ip6_v6only = 1;
301 
302 u_int32_t ip6_id = 0UL;
303 int	ip6_keepfaith = 0;
304 time_t	ip6_log_time = (time_t)0L;
305 
306 /* icmp6 */
307 /*
308  * BSDI4 defines these variables in in_proto.c...
309  * XXX: what if we don't define INET? Should we define pmtu6_expire
310  * or so? (jinmei@kame.net 19990310)
311  */
312 int pmtu_expire = 60*10;
313 int pmtu_probe = 60*2;
314 
315 /* raw IP6 parameters */
316 /*
317  * Nominal space allocated to a raw ip socket.
318  */
319 #define	RIPV6SNDQ	8192
320 #define	RIPV6RCVQ	8192
321 
322 u_long	rip6_sendspace = RIPV6SNDQ;
323 u_long	rip6_recvspace = RIPV6RCVQ;
324 
325 /* ICMPV6 parameters */
326 int	icmp6_rediraccept = 1;		/* accept and process redirects */
327 int	icmp6_redirtimeout = 10 * 60;	/* 10 minutes */
328 int	icmp6errppslim = 100;		/* 100pps */
329 int	icmp6_nodeinfo = 3;		/* enable/disable NI response */
330 
331 /* UDP on IP6 parameters */
332 int	udp6_sendspace = 9216;		/* really max datagram size */
333 int	udp6_recvspace = 40 * (1024 + sizeof(struct sockaddr_in6));
334 					/* 40 1K datagrams */
335 
336 /*
337  * sysctl related items.
338  */
339 SYSCTL_NODE(_net,	PF_INET6,	inet6,	CTLFLAG_RW,	0,
340 	"Internet6 Family");
341 
342 /* net.inet6 */
343 SYSCTL_NODE(_net_inet6,	IPPROTO_IPV6,	ip6,	CTLFLAG_RW, 0,	"IP6");
344 SYSCTL_NODE(_net_inet6,	IPPROTO_ICMPV6,	icmp6,	CTLFLAG_RW, 0,	"ICMP6");
345 SYSCTL_NODE(_net_inet6,	IPPROTO_UDP,	udp6,	CTLFLAG_RW, 0,	"UDP6");
346 SYSCTL_NODE(_net_inet6,	IPPROTO_TCP,	tcp6,	CTLFLAG_RW, 0,	"TCP6");
347 #ifdef IPSEC
348 SYSCTL_NODE(_net_inet6,	IPPROTO_ESP,	ipsec6,	CTLFLAG_RW, 0,	"IPSEC6");
349 #endif /* IPSEC */
350 
351 /* net.inet6.ip6 */
352 static int
353 sysctl_ip6_temppltime(SYSCTL_HANDLER_ARGS)
354 {
355 	int error = 0;
356 	int old;
357 
358 	error = SYSCTL_OUT(req, arg1, sizeof(int));
359 	if (error || !req->newptr)
360 		return (error);
361 	old = ip6_temp_preferred_lifetime;
362 	error = SYSCTL_IN(req, arg1, sizeof(int));
363 	if (ip6_temp_preferred_lifetime <
364 	    ip6_desync_factor + ip6_temp_regen_advance) {
365 		ip6_temp_preferred_lifetime = old;
366 		return(EINVAL);
367 	}
368 	return(error);
369 }
370 
371 static int
372 sysctl_ip6_tempvltime(SYSCTL_HANDLER_ARGS)
373 {
374 	int error = 0;
375 	int old;
376 
377 	error = SYSCTL_OUT(req, arg1, sizeof(int));
378 	if (error || !req->newptr)
379 		return (error);
380 	old = ip6_temp_valid_lifetime;
381 	error = SYSCTL_IN(req, arg1, sizeof(int));
382 	if (ip6_temp_valid_lifetime < ip6_temp_preferred_lifetime) {
383 		ip6_temp_preferred_lifetime = old;
384 		return(EINVAL);
385 	}
386 	return(error);
387 }
388 
389 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_FORWARDING,
390 	forwarding, CTLFLAG_RW, 	&ip6_forwarding,	0, "");
391 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_SENDREDIRECTS,
392 	redirect, CTLFLAG_RW,		&ip6_sendredirects,	0, "");
393 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_DEFHLIM,
394 	hlim, CTLFLAG_RW,		&ip6_defhlim,	0, "");
395 SYSCTL_STRUCT(_net_inet6_ip6, IPV6CTL_STATS, stats, CTLFLAG_RD,
396 	&ip6stat, ip6stat, "");
397 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_MAXFRAGPACKETS,
398 	maxfragpackets, CTLFLAG_RW,	&ip6_maxfragpackets,	0, "");
399 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_ACCEPT_RTADV,
400 	accept_rtadv, CTLFLAG_RW,	&ip6_accept_rtadv,	0, "");
401 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_KEEPFAITH,
402 	keepfaith, CTLFLAG_RW,		&ip6_keepfaith,	0, "");
403 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_LOG_INTERVAL,
404 	log_interval, CTLFLAG_RW,	&ip6_log_interval,	0, "");
405 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_HDRNESTLIMIT,
406 	hdrnestlimit, CTLFLAG_RW,	&ip6_hdrnestlimit,	0, "");
407 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_DAD_COUNT,
408 	dad_count, CTLFLAG_RW,	&ip6_dad_count,	0, "");
409 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_AUTO_FLOWLABEL,
410 	auto_flowlabel, CTLFLAG_RW,	&ip6_auto_flowlabel,	0, "");
411 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_DEFMCASTHLIM,
412 	defmcasthlim, CTLFLAG_RW,	&ip6_defmcasthlim,	0, "");
413 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_GIF_HLIM,
414 	gifhlim, CTLFLAG_RW,	&ip6_gif_hlim,			0, "");
415 SYSCTL_STRING(_net_inet6_ip6, IPV6CTL_KAME_VERSION,
416 	kame_version, CTLFLAG_RD,	__KAME_VERSION,		0, "");
417 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_USE_DEPRECATED,
418 	use_deprecated, CTLFLAG_RW,	&ip6_use_deprecated,	0, "");
419 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_RR_PRUNE,
420 	rr_prune, CTLFLAG_RW,	&ip6_rr_prune,			0, "");
421 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_USETEMPADDR,
422 	use_tempaddr, CTLFLAG_RW, &ip6_use_tempaddr,		0, "");
423 SYSCTL_OID(_net_inet6_ip6, IPV6CTL_TEMPPLTIME, temppltime,
424 	   CTLTYPE_INT|CTLFLAG_RW, &ip6_temp_preferred_lifetime, 0,
425 	   sysctl_ip6_temppltime, "I", "");
426 SYSCTL_OID(_net_inet6_ip6, IPV6CTL_TEMPVLTIME, tempvltime,
427 	   CTLTYPE_INT|CTLFLAG_RW, &ip6_temp_valid_lifetime, 0,
428 	   sysctl_ip6_tempvltime, "I", "");
429 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_V6ONLY,
430 	v6only,	CTLFLAG_RW,	&ip6_v6only,			0, "");
431 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_AUTO_LINKLOCAL,
432 	auto_linklocal, CTLFLAG_RW, &ip6_auto_linklocal,	0, "");
433 SYSCTL_STRUCT(_net_inet6_ip6, IPV6CTL_RIP6STATS, rip6stats, CTLFLAG_RD,
434 	&rip6stat, rip6stat, "");
435 
436 /* net.inet6.icmp6 */
437 SYSCTL_INT(_net_inet6_icmp6, ICMPV6CTL_REDIRACCEPT,
438 	rediraccept, CTLFLAG_RW,	&icmp6_rediraccept,	0, "");
439 SYSCTL_INT(_net_inet6_icmp6, ICMPV6CTL_REDIRTIMEOUT,
440 	redirtimeout, CTLFLAG_RW,	&icmp6_redirtimeout,	0, "");
441 SYSCTL_STRUCT(_net_inet6_icmp6, ICMPV6CTL_STATS, stats, CTLFLAG_RD,
442 	&icmp6stat, icmp6stat, "");
443 SYSCTL_INT(_net_inet6_icmp6, ICMPV6CTL_ND6_PRUNE,
444 	nd6_prune, CTLFLAG_RW,		&nd6_prune,	0, "");
445 SYSCTL_INT(_net_inet6_icmp6, ICMPV6CTL_ND6_DELAY,
446 	nd6_delay, CTLFLAG_RW,		&nd6_delay,	0, "");
447 SYSCTL_INT(_net_inet6_icmp6, ICMPV6CTL_ND6_UMAXTRIES,
448 	nd6_umaxtries, CTLFLAG_RW,	&nd6_umaxtries,	0, "");
449 SYSCTL_INT(_net_inet6_icmp6, ICMPV6CTL_ND6_MMAXTRIES,
450 	nd6_mmaxtries, CTLFLAG_RW,	&nd6_mmaxtries,	0, "");
451 SYSCTL_INT(_net_inet6_icmp6, ICMPV6CTL_ND6_USELOOPBACK,
452 	nd6_useloopback, CTLFLAG_RW,	&nd6_useloopback, 0, "");
453 SYSCTL_INT(_net_inet6_icmp6, ICMPV6CTL_NODEINFO,
454 	nodeinfo, CTLFLAG_RW,	&icmp6_nodeinfo,	0, "");
455 SYSCTL_INT(_net_inet6_icmp6, ICMPV6CTL_ERRPPSLIMIT,
456 	errppslimit, CTLFLAG_RW,	&icmp6errppslim,	0, "");
457 SYSCTL_INT(_net_inet6_icmp6, ICMPV6CTL_ND6_MAXNUDHINT,
458 	nd6_maxnudhint, CTLFLAG_RW,	&nd6_maxnudhint, 0, "");
459 SYSCTL_INT(_net_inet6_icmp6, ICMPV6CTL_ND6_DEBUG,
460 	nd6_debug, CTLFLAG_RW,	&nd6_debug,		0, "");
461