xref: /netbsd-src/sys/netinet6/ip6_mroute.c (revision cac8e449158efc7261bebc8657cbb0125a2cfdde)
1 /*	$NetBSD: ip6_mroute.c,v 1.95 2008/06/24 10:35:14 gmcgarry Exp $	*/
2 /*	$KAME: ip6_mroute.c,v 1.49 2001/07/25 09:21:18 jinmei Exp $	*/
3 
4 /*
5  * Copyright (C) 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 /*	BSDI ip_mroute.c,v 2.10 1996/11/14 00:29:52 jch Exp	*/
34 
35 /*
36  * Copyright (c) 1992, 1993
37  *      The Regents of the University of California.  All rights reserved.
38  *
39  * This code is derived from software contributed to Berkeley by
40  * Stephen Deering of Stanford University.
41  *
42  * Redistribution and use in source and binary forms, with or without
43  * modification, are permitted provided that the following conditions
44  * are met:
45  * 1. Redistributions of source code must retain the above copyright
46  *    notice, this list of conditions and the following disclaimer.
47  * 2. Redistributions in binary form must reproduce the above copyright
48  *    notice, this list of conditions and the following disclaimer in the
49  *    documentation and/or other materials provided with the distribution.
50  * 3. Neither the name of the University nor the names of its contributors
51  *    may be used to endorse or promote products derived from this software
52  *    without specific prior written permission.
53  *
54  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
55  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
56  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
57  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
58  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
59  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
60  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
61  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
62  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
63  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
64  * SUCH DAMAGE.
65  *
66  *      @(#)ip_mroute.c 8.2 (Berkeley) 11/15/93
67  */
68 
69 /*
70  * Copyright (c) 1989 Stephen Deering
71  *
72  * This code is derived from software contributed to Berkeley by
73  * Stephen Deering of Stanford University.
74  *
75  * Redistribution and use in source and binary forms, with or without
76  * modification, are permitted provided that the following conditions
77  * are met:
78  * 1. Redistributions of source code must retain the above copyright
79  *    notice, this list of conditions and the following disclaimer.
80  * 2. Redistributions in binary form must reproduce the above copyright
81  *    notice, this list of conditions and the following disclaimer in the
82  *    documentation and/or other materials provided with the distribution.
83  * 3. All advertising materials mentioning features or use of this software
84  *    must display the following acknowledgement:
85  *      This product includes software developed by the University of
86  *      California, Berkeley and its contributors.
87  * 4. Neither the name of the University nor the names of its contributors
88  *    may be used to endorse or promote products derived from this software
89  *    without specific prior written permission.
90  *
91  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
92  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
93  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
94  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
95  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
96  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
97  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
98  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
99  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
100  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
101  * SUCH DAMAGE.
102  *
103  *      @(#)ip_mroute.c 8.2 (Berkeley) 11/15/93
104  */
105 
106 /*
107  * IP multicast forwarding procedures
108  *
109  * Written by David Waitzman, BBN Labs, August 1988.
110  * Modified by Steve Deering, Stanford, February 1989.
111  * Modified by Mark J. Steiglitz, Stanford, May, 1991
112  * Modified by Van Jacobson, LBL, January 1993
113  * Modified by Ajit Thyagarajan, PARC, August 1993
114  * Modified by Bill Fenner, PARC, April 1994
115  *
116  * MROUTING Revision: 3.5.1.2 + PIM-SMv2 (pimd) Support
117  */
118 
119 #include <sys/cdefs.h>
120 __KERNEL_RCSID(0, "$NetBSD: ip6_mroute.c,v 1.95 2008/06/24 10:35:14 gmcgarry Exp $");
121 
122 #include "opt_inet.h"
123 #include "opt_mrouting.h"
124 
125 #include <sys/param.h>
126 #include <sys/systm.h>
127 #include <sys/callout.h>
128 #include <sys/mbuf.h>
129 #include <sys/socket.h>
130 #include <sys/socketvar.h>
131 #include <sys/sockio.h>
132 #include <sys/protosw.h>
133 #include <sys/errno.h>
134 #include <sys/time.h>
135 #include <sys/kernel.h>
136 #include <sys/ioctl.h>
137 #include <sys/sysctl.h>
138 #include <sys/syslog.h>
139 
140 #include <net/if.h>
141 #include <net/route.h>
142 #include <net/raw_cb.h>
143 #include <net/net_stats.h>
144 
145 #include <netinet/in.h>
146 #include <netinet/in_var.h>
147 #include <netinet/icmp6.h>
148 
149 #include <netinet/ip6.h>
150 #include <netinet6/ip6_var.h>
151 #include <netinet6/ip6_private.h>
152 #include <netinet6/ip6_mroute.h>
153 #include <netinet6/scope6_var.h>
154 #include <netinet6/pim6.h>
155 #include <netinet6/pim6_var.h>
156 #include <netinet6/nd6.h>
157 
158 #include <net/net_osdep.h>
159 
160 static int ip6_mdq(struct mbuf *, struct ifnet *, struct mf6c *);
161 static void phyint_send(struct ip6_hdr *, struct mif6 *, struct mbuf *);
162 
163 static int set_pim6(int *);
164 static int get_pim6(struct mbuf *);
165 static int socket_send(struct socket *, struct mbuf *,
166 	    struct sockaddr_in6 *);
167 static int register_send(struct ip6_hdr *, struct mif6 *, struct mbuf *);
168 
169 /*
170  * Globals.  All but ip6_mrouter, ip6_mrtproto and mrt6stat could be static,
171  * except for netstat or debugging purposes.
172  */
173 struct socket  *ip6_mrouter = NULL;
174 int		ip6_mrouter_ver = 0;
175 int		ip6_mrtproto = IPPROTO_PIM;    /* for netstat only */
176 struct mrt6stat	mrt6stat;
177 
178 #define NO_RTE_FOUND 	0x1
179 #define RTE_FOUND	0x2
180 
181 struct mf6c	*mf6ctable[MF6CTBLSIZ];
182 u_char		n6expire[MF6CTBLSIZ];
183 struct mif6 mif6table[MAXMIFS];
184 #ifdef MRT6DEBUG
185 u_int		mrt6debug = 0;	  /* debug level 	*/
186 #define DEBUG_MFC	0x02
187 #define DEBUG_FORWARD	0x04
188 #define DEBUG_EXPIRE	0x08
189 #define DEBUG_XMIT	0x10
190 #define DEBUG_REG	0x20
191 #define DEBUG_PIM	0x40
192 #endif
193 
194 static void	expire_upcalls(void *);
195 #define	EXPIRE_TIMEOUT	(hz / 4)	/* 4x / second */
196 #define	UPCALL_EXPIRE	6		/* number of timeouts */
197 
198 #ifdef INET
199 #ifdef MROUTING
200 extern struct socket *ip_mrouter;
201 #endif
202 #endif
203 
204 /*
205  * 'Interfaces' associated with decapsulator (so we can tell
206  * packets that went through it from ones that get reflected
207  * by a broken gateway).  These interfaces are never linked into
208  * the system ifnet list & no routes point to them.  I.e., packets
209  * can't be sent this way.  They only exist as a placeholder for
210  * multicast source verification.
211  */
212 struct ifnet multicast_register_if6;
213 
214 #define ENCAP_HOPS 64
215 
216 /*
217  * Private variables.
218  */
219 static mifi_t nummifs = 0;
220 static mifi_t reg_mif_num = (mifi_t)-1;
221 
222 static percpu_t *pim6stat_percpu;
223 
224 #define	PIM6_STATINC(x)		_NET_STATINC(pim6stat_percpu, x)
225 
226 static int pim6;
227 
228 /*
229  * Hash function for a source, group entry
230  */
231 #define MF6CHASH(a, g) MF6CHASHMOD((a).s6_addr32[0] ^ (a).s6_addr32[1] ^ \
232 				   (a).s6_addr32[2] ^ (a).s6_addr32[3] ^ \
233 				   (g).s6_addr32[0] ^ (g).s6_addr32[1] ^ \
234 				   (g).s6_addr32[2] ^ (g).s6_addr32[3])
235 
236 /*
237  * Find a route for a given origin IPv6 address and Multicast group address.
238  * Quality of service parameter to be added in the future!!!
239  */
240 
241 #define MF6CFIND(o, g, rt) do { \
242 	struct mf6c *_rt = mf6ctable[MF6CHASH(o,g)]; \
243 	rt = NULL; \
244 	mrt6stat.mrt6s_mfc_lookups++; \
245 	while (_rt) { \
246 		if (IN6_ARE_ADDR_EQUAL(&_rt->mf6c_origin.sin6_addr, &(o)) && \
247 		    IN6_ARE_ADDR_EQUAL(&_rt->mf6c_mcastgrp.sin6_addr, &(g)) && \
248 		    (_rt->mf6c_stall == NULL)) { \
249 			rt = _rt; \
250 			break; \
251 		} \
252 		_rt = _rt->mf6c_next; \
253 	} \
254 	if (rt == NULL) { \
255 		mrt6stat.mrt6s_mfc_misses++; \
256 	} \
257 } while (/*CONSTCOND*/ 0)
258 
259 /*
260  * Macros to compute elapsed time efficiently
261  * Borrowed from Van Jacobson's scheduling code
262  */
263 #define TV_DELTA(a, b, delta) do { \
264 	    int xxs; \
265 		\
266 	    delta = (a).tv_usec - (b).tv_usec; \
267 	    if ((xxs = (a).tv_sec - (b).tv_sec)) { \
268 	       switch (xxs) { \
269 		      case 2: \
270 			  delta += 1000000; \
271 			      /* FALLTHROUGH */ \
272 		      case 1: \
273 			  delta += 1000000; \
274 			  break; \
275 		      default: \
276 			  delta += (1000000 * xxs); \
277 	       } \
278 	    } \
279 } while (/*CONSTCOND*/ 0)
280 
281 #define TV_LT(a, b) (((a).tv_usec < (b).tv_usec && \
282 	      (a).tv_sec <= (b).tv_sec) || (a).tv_sec < (b).tv_sec)
283 
284 #ifdef UPCALL_TIMING
285 #define UPCALL_MAX	50
286 u_long upcall_data[UPCALL_MAX + 1];
287 static void collate();
288 #endif /* UPCALL_TIMING */
289 
290 static int get_sg_cnt(struct sioc_sg_req6 *);
291 static int get_mif6_cnt(struct sioc_mif_req6 *);
292 static int ip6_mrouter_init(struct socket *, int, int);
293 static int add_m6if(struct mif6ctl *);
294 static int del_m6if(mifi_t *);
295 static int add_m6fc(struct mf6cctl *);
296 static int del_m6fc(struct mf6cctl *);
297 
298 static callout_t expire_upcalls_ch;
299 
300 void
301 pim6_init(void)
302 {
303 
304 	pim6stat_percpu = percpu_alloc(sizeof(uint64_t) * PIM6_NSTATS);
305 }
306 
307 /*
308  * Handle MRT setsockopt commands to modify the multicast routing tables.
309  */
310 int
311 ip6_mrouter_set(int cmd, struct socket *so, struct mbuf *m)
312 {
313 	if (cmd != MRT6_INIT && so != ip6_mrouter)
314 		return (EACCES);
315 
316 	switch (cmd) {
317 #ifdef MRT6_OINIT
318 	case MRT6_OINIT:
319 #endif
320 	case MRT6_INIT:
321 		if (m == NULL || m->m_len != sizeof(int))
322 			return (EINVAL);
323 		return (ip6_mrouter_init(so, *mtod(m, int *), cmd));
324 	case MRT6_DONE:
325 		return (ip6_mrouter_done());
326 	case MRT6_ADD_MIF:
327 		if (m == NULL || m->m_len != sizeof(struct mif6ctl))
328 			return (EINVAL);
329 		return (add_m6if(mtod(m, struct mif6ctl *)));
330 	case MRT6_DEL_MIF:
331 		if (m == NULL || m->m_len != sizeof(mifi_t))
332 			return (EINVAL);
333 		return (del_m6if(mtod(m, mifi_t *)));
334 	case MRT6_ADD_MFC:
335 		if (m == NULL || m->m_len != sizeof(struct mf6cctl))
336 			return (EINVAL);
337 		return (add_m6fc(mtod(m, struct mf6cctl *)));
338 	case MRT6_DEL_MFC:
339 		if (m == NULL || m->m_len != sizeof(struct mf6cctl))
340 			return (EINVAL);
341 		return (del_m6fc(mtod(m,  struct mf6cctl *)));
342 	case MRT6_PIM:
343 		if (m == NULL || m->m_len != sizeof(int))
344 			return (EINVAL);
345 		return (set_pim6(mtod(m, int *)));
346 	default:
347 		return (EOPNOTSUPP);
348 	}
349 }
350 
351 /*
352  * Handle MRT getsockopt commands
353  */
354 int
355 ip6_mrouter_get(int cmd, struct socket *so, struct mbuf **m)
356 {
357 	struct mbuf *mb;
358 
359 	if (so != ip6_mrouter) return EACCES;
360 
361 	*m = mb = m_get(M_WAIT, MT_SOOPTS);
362 
363 	switch (cmd) {
364 	case MRT6_PIM:
365 		return get_pim6(mb);
366 	default:
367 		m_free(mb);
368 		return EOPNOTSUPP;
369 	}
370 }
371 
372 /*
373  * Handle ioctl commands to obtain information from the cache
374  */
375 int
376 mrt6_ioctl(u_long cmd, void *data)
377 {
378 
379 	switch (cmd) {
380 	case SIOCGETSGCNT_IN6:
381 		return (get_sg_cnt((struct sioc_sg_req6 *)data));
382 	case SIOCGETMIFCNT_IN6:
383 		return (get_mif6_cnt((struct sioc_mif_req6 *)data));
384 	default:
385 		return (EINVAL);
386 	}
387 }
388 
389 /*
390  * returns the packet, byte, rpf-failure count for the source group provided
391  */
392 static int
393 get_sg_cnt(struct sioc_sg_req6 *req)
394 {
395 	struct mf6c *rt;
396 	int s;
397 
398 	s = splsoftnet();
399 	MF6CFIND(req->src.sin6_addr, req->grp.sin6_addr, rt);
400 	splx(s);
401 	if (rt != NULL) {
402 		req->pktcnt = rt->mf6c_pkt_cnt;
403 		req->bytecnt = rt->mf6c_byte_cnt;
404 		req->wrong_if = rt->mf6c_wrong_if;
405 	} else
406 		return (ESRCH);
407 #if 0
408 		req->pktcnt = req->bytecnt = req->wrong_if = 0xffffffff;
409 #endif
410 
411 	return 0;
412 }
413 
414 /*
415  * returns the input and output packet and byte counts on the mif provided
416  */
417 static int
418 get_mif6_cnt(struct sioc_mif_req6 *req)
419 {
420 	mifi_t mifi = req->mifi;
421 
422 	if (mifi >= nummifs)
423 		return EINVAL;
424 
425 	req->icount = mif6table[mifi].m6_pkt_in;
426 	req->ocount = mif6table[mifi].m6_pkt_out;
427 	req->ibytes = mif6table[mifi].m6_bytes_in;
428 	req->obytes = mif6table[mifi].m6_bytes_out;
429 
430 	return 0;
431 }
432 
433 /*
434  * Get PIM processiong global
435  */
436 static int
437 get_pim6(struct mbuf *m)
438 {
439 	int *i;
440 
441 	i = mtod(m, int *);
442 
443 	*i = pim6;
444 
445 	return 0;
446 }
447 
448 static int
449 set_pim6(int *i)
450 {
451 	if ((*i != 1) && (*i != 0))
452 		return EINVAL;
453 
454 	pim6 = *i;
455 
456 	return 0;
457 }
458 
459 /*
460  * Enable multicast routing
461  */
462 static int
463 ip6_mrouter_init(struct socket *so, int v, int cmd)
464 {
465 #ifdef MRT6DEBUG
466 	if (mrt6debug)
467 		log(LOG_DEBUG,
468 		    "ip6_mrouter_init: so_type = %d, pr_protocol = %d\n",
469 		    so->so_type, so->so_proto->pr_protocol);
470 #endif
471 
472 	if (so->so_type != SOCK_RAW ||
473 	    so->so_proto->pr_protocol != IPPROTO_ICMPV6)
474 		return (EOPNOTSUPP);
475 
476 	if (v != 1)
477 		return (ENOPROTOOPT);
478 
479 	if (ip6_mrouter != NULL)
480 		return (EADDRINUSE);
481 
482 	ip6_mrouter = so;
483 	ip6_mrouter_ver = cmd;
484 
485 	bzero((void *)mf6ctable, sizeof(mf6ctable));
486 	bzero((void *)n6expire, sizeof(n6expire));
487 
488 	pim6 = 0;/* used for stubbing out/in pim stuff */
489 
490 	callout_init(&expire_upcalls_ch, CALLOUT_MPSAFE);
491 	callout_reset(&expire_upcalls_ch, EXPIRE_TIMEOUT,
492 	    expire_upcalls, NULL);
493 
494 #ifdef MRT6DEBUG
495 	if (mrt6debug)
496 		log(LOG_DEBUG, "ip6_mrouter_init\n");
497 #endif
498 
499 	return 0;
500 }
501 
502 /*
503  * Disable multicast routing
504  */
505 int
506 ip6_mrouter_done(void)
507 {
508 	mifi_t mifi;
509 	int i;
510 	struct ifnet *ifp;
511 	struct in6_ifreq ifr;
512 	struct mf6c *rt;
513 	struct rtdetq *rte;
514 	int s;
515 
516 	s = splsoftnet();
517 
518 	/*
519 	 * For each phyint in use, disable promiscuous reception of all IPv6
520 	 * multicasts.
521 	 */
522 #ifdef INET
523 #ifdef MROUTING
524 	/*
525 	 * If there is still IPv4 multicast routing daemon,
526 	 * we remain interfaces to receive all muliticasted packets.
527 	 * XXX: there may be an interface in which the IPv4 multicast
528 	 * daemon is not interested...
529 	 */
530 	if (!ip_mrouter)
531 #endif
532 #endif
533 	{
534 		for (mifi = 0; mifi < nummifs; mifi++) {
535 			if (mif6table[mifi].m6_ifp &&
536 			    !(mif6table[mifi].m6_flags & MIFF_REGISTER)) {
537 				ifr.ifr_addr.sin6_family = AF_INET6;
538 				ifr.ifr_addr.sin6_addr= in6addr_any;
539 				ifp = mif6table[mifi].m6_ifp;
540 				(*ifp->if_ioctl)(ifp, SIOCDELMULTI, &ifr);
541 			}
542 		}
543 	}
544 #ifdef notyet
545 	bzero((void *)qtable, sizeof(qtable));
546 	bzero((void *)tbftable, sizeof(tbftable));
547 #endif
548 	bzero((void *)mif6table, sizeof(mif6table));
549 	nummifs = 0;
550 
551 	pim6 = 0; /* used to stub out/in pim specific code */
552 
553 	callout_stop(&expire_upcalls_ch);
554 
555 	/*
556 	 * Free all multicast forwarding cache entries.
557 	 */
558 	for (i = 0; i < MF6CTBLSIZ; i++) {
559 		rt = mf6ctable[i];
560 		while (rt) {
561 			struct mf6c *frt;
562 
563 			for (rte = rt->mf6c_stall; rte != NULL; ) {
564 				struct rtdetq *n = rte->next;
565 
566 				m_free(rte->m);
567 				free(rte, M_MRTABLE);
568 				rte = n;
569 			}
570 			frt = rt;
571 			rt = rt->mf6c_next;
572 			free(frt, M_MRTABLE);
573 		}
574 	}
575 
576 	bzero((void *)mf6ctable, sizeof(mf6ctable));
577 
578 	/*
579 	 * Reset register interface
580 	 */
581 	if (reg_mif_num != (mifi_t)-1) {
582 		if_detach(&multicast_register_if6);
583 		reg_mif_num = (mifi_t)-1;
584 	}
585 
586 	ip6_mrouter = NULL;
587 	ip6_mrouter_ver = 0;
588 
589 	splx(s);
590 
591 #ifdef MRT6DEBUG
592 	if (mrt6debug)
593 		log(LOG_DEBUG, "ip6_mrouter_done\n");
594 #endif
595 
596 	return 0;
597 }
598 
599 void
600 ip6_mrouter_detach(struct ifnet *ifp)
601 {
602 	struct rtdetq *rte;
603 	struct mf6c *mfc;
604 	mifi_t mifi;
605 	int i;
606 
607 	if (ip6_mrouter == NULL)
608 		return;
609 
610 	/*
611 	 * Delete a mif which points to ifp.
612 	 */
613 	for (mifi = 0; mifi < nummifs; mifi++)
614 		if (mif6table[mifi].m6_ifp == ifp)
615 			del_m6if(&mifi);
616 
617 	/*
618 	 * Clear rte->ifp of cache entries received on ifp.
619 	 */
620 	for (i = 0; i < MF6CTBLSIZ; i++) {
621 		if (n6expire[i] == 0)
622 			continue;
623 
624 		for (mfc = mf6ctable[i]; mfc != NULL; mfc = mfc->mf6c_next) {
625 			for (rte = mfc->mf6c_stall; rte != NULL; rte = rte->next) {
626 				if (rte->ifp == ifp)
627 					rte->ifp = NULL;
628 			}
629 		}
630 	}
631 }
632 
633 
634 /*
635  * Add a mif to the mif table
636  */
637 static int
638 add_m6if(struct mif6ctl *mifcp)
639 {
640 	struct mif6 *mifp;
641 	struct ifnet *ifp;
642 	struct in6_ifreq ifr;
643 	int error, s;
644 #ifdef notyet
645 	struct tbf *m_tbf = tbftable + mifcp->mif6c_mifi;
646 #endif
647 
648 	if (mifcp->mif6c_mifi >= MAXMIFS)
649 		return EINVAL;
650 	mifp = mif6table + mifcp->mif6c_mifi;
651 	if (mifp->m6_ifp)
652 		return EADDRINUSE; /* XXX: is it appropriate? */
653 	if (mifcp->mif6c_pifi == 0 || mifcp->mif6c_pifi >= if_indexlim)
654 		return ENXIO;
655 	/*
656 	 * XXX: some OSes can remove ifp and clear ifindex2ifnet[id]
657 	 * even for id between 0 and if_index.
658 	 */
659 	if ((ifp = ifindex2ifnet[mifcp->mif6c_pifi]) == NULL)
660 		return ENXIO;
661 
662 	if (mifcp->mif6c_flags & MIFF_REGISTER) {
663 		ifp = &multicast_register_if6;
664 
665 		if (reg_mif_num == (mifi_t)-1) {
666 			strlcpy(ifp->if_xname, "register_mif",
667 			    sizeof(ifp->if_xname));
668 			ifp->if_flags |= IFF_LOOPBACK;
669 			ifp->if_index = mifcp->mif6c_mifi;
670 			reg_mif_num = mifcp->mif6c_mifi;
671 			if_attach(ifp);
672 		}
673 
674 	} /* if REGISTER */
675 	else {
676 		/* Make sure the interface supports multicast */
677 		if ((ifp->if_flags & IFF_MULTICAST) == 0)
678 			return EOPNOTSUPP;
679 
680 		s = splsoftnet();
681 		/*
682 		 * Enable promiscuous reception of all IPv6 multicasts
683 		 * from the interface.
684 		 */
685 		ifr.ifr_addr.sin6_family = AF_INET6;
686 		ifr.ifr_addr.sin6_addr = in6addr_any;
687 		error = (*ifp->if_ioctl)(ifp, SIOCADDMULTI, &ifr);
688 		splx(s);
689 		if (error)
690 			return error;
691 	}
692 
693 	s = splsoftnet();
694 	mifp->m6_flags     = mifcp->mif6c_flags;
695 	mifp->m6_ifp       = ifp;
696 #ifdef notyet
697 	/* scaling up here allows division by 1024 in critical code */
698 	mifp->m6_rate_limit = mifcp->mif6c_rate_limit * 1024 / 1000;
699 #endif
700 	/* initialize per mif pkt counters */
701 	mifp->m6_pkt_in    = 0;
702 	mifp->m6_pkt_out   = 0;
703 	mifp->m6_bytes_in  = 0;
704 	mifp->m6_bytes_out = 0;
705 	splx(s);
706 
707 	/* Adjust nummifs up if the mifi is higher than nummifs */
708 	if (nummifs <= mifcp->mif6c_mifi)
709 		nummifs = mifcp->mif6c_mifi + 1;
710 
711 #ifdef MRT6DEBUG
712 	if (mrt6debug)
713 		log(LOG_DEBUG,
714 		    "add_mif #%d, phyint %s\n",
715 		    mifcp->mif6c_mifi, ifp->if_xname);
716 #endif
717 
718 	return 0;
719 }
720 
721 /*
722  * Delete a mif from the mif table
723  */
724 static int
725 del_m6if(mifi_t *mifip)
726 {
727 	struct mif6 *mifp = mif6table + *mifip;
728 	mifi_t mifi;
729 	struct ifnet *ifp;
730 	struct in6_ifreq ifr;
731 	int s;
732 
733 	if (*mifip >= nummifs)
734 		return EINVAL;
735 	if (mifp->m6_ifp == NULL)
736 		return EINVAL;
737 
738 	s = splsoftnet();
739 
740 	if (!(mifp->m6_flags & MIFF_REGISTER)) {
741 		/*
742 		 * XXX: what if there is yet IPv4 multicast daemon
743 		 *      using the interface?
744 		 */
745 		ifp = mifp->m6_ifp;
746 
747 		ifr.ifr_addr.sin6_family = AF_INET6;
748 		ifr.ifr_addr.sin6_addr = in6addr_any;
749 		(*ifp->if_ioctl)(ifp, SIOCDELMULTI, &ifr);
750 	} else {
751 		if (reg_mif_num != (mifi_t)-1) {
752 			if_detach(&multicast_register_if6);
753 			reg_mif_num = (mifi_t)-1;
754 		}
755 	}
756 
757 #ifdef notyet
758 	bzero((void *)qtable[*mifip], sizeof(qtable[*mifip]));
759 	bzero((void *)mifp->m6_tbf, sizeof(*(mifp->m6_tbf)));
760 #endif
761 	bzero((void *)mifp, sizeof (*mifp));
762 
763 	/* Adjust nummifs down */
764 	for (mifi = nummifs; mifi > 0; mifi--)
765 		if (mif6table[mifi - 1].m6_ifp)
766 			break;
767 	nummifs = mifi;
768 
769 	splx(s);
770 
771 #ifdef MRT6DEBUG
772 	if (mrt6debug)
773 		log(LOG_DEBUG, "del_m6if %d, nummifs %d\n", *mifip, nummifs);
774 #endif
775 
776 	return 0;
777 }
778 
779 /*
780  * Add an mfc entry
781  */
782 static int
783 add_m6fc(struct mf6cctl *mfccp)
784 {
785 	struct mf6c *rt;
786 	u_long hash;
787 	struct rtdetq *rte;
788 	u_short nstl;
789 	int s;
790 
791 	MF6CFIND(mfccp->mf6cc_origin.sin6_addr,
792 		 mfccp->mf6cc_mcastgrp.sin6_addr, rt);
793 
794 	/* If an entry already exists, just update the fields */
795 	if (rt) {
796 #ifdef MRT6DEBUG
797 		if (mrt6debug & DEBUG_MFC)
798 			log(LOG_DEBUG,"add_m6fc update o %s g %s p %x\n",
799 			    ip6_sprintf(&mfccp->mf6cc_origin.sin6_addr),
800 			    ip6_sprintf(&mfccp->mf6cc_mcastgrp.sin6_addr),
801 			    mfccp->mf6cc_parent);
802 #endif
803 
804 		s = splsoftnet();
805 		rt->mf6c_parent = mfccp->mf6cc_parent;
806 		rt->mf6c_ifset = mfccp->mf6cc_ifset;
807 		splx(s);
808 		return 0;
809 	}
810 
811 	/*
812 	 * Find the entry for which the upcall was made and update
813 	 */
814 	s = splsoftnet();
815 	hash = MF6CHASH(mfccp->mf6cc_origin.sin6_addr,
816 			mfccp->mf6cc_mcastgrp.sin6_addr);
817 	for (rt = mf6ctable[hash], nstl = 0; rt; rt = rt->mf6c_next) {
818 		if (IN6_ARE_ADDR_EQUAL(&rt->mf6c_origin.sin6_addr,
819 				       &mfccp->mf6cc_origin.sin6_addr) &&
820 		    IN6_ARE_ADDR_EQUAL(&rt->mf6c_mcastgrp.sin6_addr,
821 				       &mfccp->mf6cc_mcastgrp.sin6_addr) &&
822 		    (rt->mf6c_stall != NULL)) {
823 
824 			if (nstl++)
825 				log(LOG_ERR,
826 				    "add_m6fc: %s o %s g %s p %x dbx %p\n",
827 				    "multiple kernel entries",
828 				    ip6_sprintf(&mfccp->mf6cc_origin.sin6_addr),
829 				    ip6_sprintf(&mfccp->mf6cc_mcastgrp.sin6_addr),
830 				    mfccp->mf6cc_parent, rt->mf6c_stall);
831 
832 #ifdef MRT6DEBUG
833 			if (mrt6debug & DEBUG_MFC)
834 				log(LOG_DEBUG,
835 				    "add_m6fc o %s g %s p %x dbg %p\n",
836 				    ip6_sprintf(&mfccp->mf6cc_origin.sin6_addr),
837 				    ip6_sprintf(&mfccp->mf6cc_mcastgrp.sin6_addr),
838 				    mfccp->mf6cc_parent, rt->mf6c_stall);
839 #endif
840 
841 			rt->mf6c_origin     = mfccp->mf6cc_origin;
842 			rt->mf6c_mcastgrp   = mfccp->mf6cc_mcastgrp;
843 			rt->mf6c_parent     = mfccp->mf6cc_parent;
844 			rt->mf6c_ifset	    = mfccp->mf6cc_ifset;
845 			/* initialize pkt counters per src-grp */
846 			rt->mf6c_pkt_cnt    = 0;
847 			rt->mf6c_byte_cnt   = 0;
848 			rt->mf6c_wrong_if   = 0;
849 
850 			rt->mf6c_expire = 0;	/* Don't clean this guy up */
851 			n6expire[hash]--;
852 
853 			/* free packets Qed at the end of this entry */
854 			for (rte = rt->mf6c_stall; rte != NULL; ) {
855 				struct rtdetq *n = rte->next;
856 				if (rte->ifp) {
857 					ip6_mdq(rte->m, rte->ifp, rt);
858 				}
859 				m_freem(rte->m);
860 #ifdef UPCALL_TIMING
861 				collate(&(rte->t));
862 #endif /* UPCALL_TIMING */
863 				free(rte, M_MRTABLE);
864 				rte = n;
865 			}
866 			rt->mf6c_stall = NULL;
867 		}
868 	}
869 
870 	/*
871 	 * It is possible that an entry is being inserted without an upcall
872 	 */
873 	if (nstl == 0) {
874 #ifdef MRT6DEBUG
875 		if (mrt6debug & DEBUG_MFC)
876 			log(LOG_DEBUG,
877 			    "add_mfc no upcall h %ld o %s g %s p %x\n",
878 			    hash,
879 			    ip6_sprintf(&mfccp->mf6cc_origin.sin6_addr),
880 			    ip6_sprintf(&mfccp->mf6cc_mcastgrp.sin6_addr),
881 			    mfccp->mf6cc_parent);
882 #endif
883 
884 		for (rt = mf6ctable[hash]; rt; rt = rt->mf6c_next) {
885 
886 			if (IN6_ARE_ADDR_EQUAL(&rt->mf6c_origin.sin6_addr,
887 					       &mfccp->mf6cc_origin.sin6_addr)&&
888 			    IN6_ARE_ADDR_EQUAL(&rt->mf6c_mcastgrp.sin6_addr,
889 					       &mfccp->mf6cc_mcastgrp.sin6_addr)) {
890 
891 				rt->mf6c_origin     = mfccp->mf6cc_origin;
892 				rt->mf6c_mcastgrp   = mfccp->mf6cc_mcastgrp;
893 				rt->mf6c_parent     = mfccp->mf6cc_parent;
894 				rt->mf6c_ifset	    = mfccp->mf6cc_ifset;
895 				/* initialize pkt counters per src-grp */
896 				rt->mf6c_pkt_cnt    = 0;
897 				rt->mf6c_byte_cnt   = 0;
898 				rt->mf6c_wrong_if   = 0;
899 
900 				if (rt->mf6c_expire)
901 					n6expire[hash]--;
902 				rt->mf6c_expire	   = 0;
903 			}
904 		}
905 		if (rt == NULL) {
906 			/* no upcall, so make a new entry */
907 			rt = (struct mf6c *)malloc(sizeof(*rt), M_MRTABLE,
908 						  M_NOWAIT);
909 			if (rt == NULL) {
910 				splx(s);
911 				return ENOBUFS;
912 			}
913 
914 			/* insert new entry at head of hash chain */
915 			rt->mf6c_origin     = mfccp->mf6cc_origin;
916 			rt->mf6c_mcastgrp   = mfccp->mf6cc_mcastgrp;
917 			rt->mf6c_parent     = mfccp->mf6cc_parent;
918 			rt->mf6c_ifset	    = mfccp->mf6cc_ifset;
919 			/* initialize pkt counters per src-grp */
920 			rt->mf6c_pkt_cnt    = 0;
921 			rt->mf6c_byte_cnt   = 0;
922 			rt->mf6c_wrong_if   = 0;
923 			rt->mf6c_expire     = 0;
924 			rt->mf6c_stall = NULL;
925 
926 			/* link into table */
927 			rt->mf6c_next  = mf6ctable[hash];
928 			mf6ctable[hash] = rt;
929 		}
930 	}
931 	splx(s);
932 	return 0;
933 }
934 
935 #ifdef UPCALL_TIMING
936 /*
937  * collect delay statistics on the upcalls
938  */
939 static void
940 collate(struct timeval *t)
941 {
942 	u_long d;
943 	struct timeval tp;
944 	u_long delta;
945 
946 	GET_TIME(tp);
947 
948 	if (TV_LT(*t, tp))
949 	{
950 		TV_DELTA(tp, *t, delta);
951 
952 		d = delta >> 10;
953 		if (d > UPCALL_MAX)
954 			d = UPCALL_MAX;
955 
956 		++upcall_data[d];
957 	}
958 }
959 #endif /* UPCALL_TIMING */
960 
961 /*
962  * Delete an mfc entry
963  */
964 static int
965 del_m6fc(struct mf6cctl *mfccp)
966 {
967 	struct sockaddr_in6 	origin;
968 	struct sockaddr_in6 	mcastgrp;
969 	struct mf6c 		*rt;
970 	struct mf6c	 	**nptr;
971 	u_long 		hash;
972 	int s;
973 
974 	origin = mfccp->mf6cc_origin;
975 	mcastgrp = mfccp->mf6cc_mcastgrp;
976 	hash = MF6CHASH(origin.sin6_addr, mcastgrp.sin6_addr);
977 
978 #ifdef MRT6DEBUG
979 	if (mrt6debug & DEBUG_MFC)
980 		log(LOG_DEBUG,"del_m6fc orig %s mcastgrp %s\n",
981 		    ip6_sprintf(&origin.sin6_addr),
982 		    ip6_sprintf(&mcastgrp.sin6_addr));
983 #endif
984 
985 	s = splsoftnet();
986 
987 	nptr = &mf6ctable[hash];
988 	while ((rt = *nptr) != NULL) {
989 		if (IN6_ARE_ADDR_EQUAL(&origin.sin6_addr,
990 				       &rt->mf6c_origin.sin6_addr) &&
991 		    IN6_ARE_ADDR_EQUAL(&mcastgrp.sin6_addr,
992 				       &rt->mf6c_mcastgrp.sin6_addr) &&
993 		    rt->mf6c_stall == NULL)
994 			break;
995 
996 		nptr = &rt->mf6c_next;
997 	}
998 	if (rt == NULL) {
999 		splx(s);
1000 		return EADDRNOTAVAIL;
1001 	}
1002 
1003 	*nptr = rt->mf6c_next;
1004 	free(rt, M_MRTABLE);
1005 
1006 	splx(s);
1007 
1008 	return 0;
1009 }
1010 
1011 static int
1012 socket_send(struct socket *s, struct mbuf *mm, struct sockaddr_in6 *src)
1013 {
1014 	if (s) {
1015 		if (sbappendaddr(&s->so_rcv,
1016 				 (struct sockaddr *)src,
1017 				 mm, (struct mbuf *)0) != 0) {
1018 			sorwakeup(s);
1019 			return 0;
1020 		}
1021 	}
1022 	m_freem(mm);
1023 	return -1;
1024 }
1025 
1026 /*
1027  * IPv6 multicast forwarding function. This function assumes that the packet
1028  * pointed to by "ip6" has arrived on (or is about to be sent to) the interface
1029  * pointed to by "ifp", and the packet is to be relayed to other networks
1030  * that have members of the packet's destination IPv6 multicast group.
1031  *
1032  * The packet is returned unscathed to the caller, unless it is
1033  * erroneous, in which case a non-zero return value tells the caller to
1034  * discard it.
1035  */
1036 
1037 int
1038 ip6_mforward(struct ip6_hdr *ip6, struct ifnet *ifp, struct mbuf *m)
1039 {
1040 	struct mf6c *rt;
1041 	struct mif6 *mifp;
1042 	struct mbuf *mm;
1043 	int s;
1044 	mifi_t mifi;
1045 	struct sockaddr_in6 sin6;
1046 
1047 #ifdef MRT6DEBUG
1048 	if (mrt6debug & DEBUG_FORWARD)
1049 		log(LOG_DEBUG, "ip6_mforward: src %s, dst %s, ifindex %d\n",
1050 		    ip6_sprintf(&ip6->ip6_src), ip6_sprintf(&ip6->ip6_dst),
1051 		    ifp->if_index);
1052 #endif
1053 
1054 	/*
1055 	 * Don't forward a packet with Hop limit of zero or one,
1056 	 * or a packet destined to a local-only group.
1057 	 */
1058 	if (ip6->ip6_hlim <= 1 || IN6_IS_ADDR_MC_NODELOCAL(&ip6->ip6_dst) ||
1059 	    IN6_IS_ADDR_MC_LINKLOCAL(&ip6->ip6_dst))
1060 		return 0;
1061 	ip6->ip6_hlim--;
1062 
1063 	/*
1064 	 * Source address check: do not forward packets with unspecified
1065 	 * source. It was discussed in July 2000, on ipngwg mailing list.
1066 	 * This is rather more serious than unicast cases, because some
1067 	 * MLD packets can be sent with the unspecified source address
1068 	 * (although such packets must normally set the hop limit field to 1).
1069 	 */
1070 	if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src)) {
1071 		IP6_STATINC(IP6_STAT_CANTFORWARD);
1072 		if (ip6_log_time + ip6_log_interval < time_second) {
1073 			ip6_log_time = time_second;
1074 			log(LOG_DEBUG,
1075 			    "cannot forward "
1076 			    "from %s to %s nxt %d received on %s\n",
1077 			    ip6_sprintf(&ip6->ip6_src),
1078 			    ip6_sprintf(&ip6->ip6_dst),
1079 			    ip6->ip6_nxt,
1080 			    m->m_pkthdr.rcvif ?
1081 			    if_name(m->m_pkthdr.rcvif) : "?");
1082 		}
1083 		return 0;
1084 	}
1085 
1086 	/*
1087 	 * Determine forwarding mifs from the forwarding cache table
1088 	 */
1089 	s = splsoftnet();
1090 	MF6CFIND(ip6->ip6_src, ip6->ip6_dst, rt);
1091 
1092 	/* Entry exists, so forward if necessary */
1093 	if (rt) {
1094 		splx(s);
1095 		return (ip6_mdq(m, ifp, rt));
1096 	} else {
1097 		/*
1098 		 * If we don't have a route for packet's origin,
1099 		 * Make a copy of the packet &
1100 		 * send message to routing daemon
1101 		 */
1102 
1103 		struct mbuf *mb0;
1104 		struct rtdetq *rte;
1105 		u_long hash;
1106 /*		int i, npkts;*/
1107 #ifdef UPCALL_TIMING
1108 		struct timeval tp;
1109 
1110 		GET_TIME(tp);
1111 #endif /* UPCALL_TIMING */
1112 
1113 		mrt6stat.mrt6s_no_route++;
1114 #ifdef MRT6DEBUG
1115 		if (mrt6debug & (DEBUG_FORWARD | DEBUG_MFC))
1116 			log(LOG_DEBUG, "ip6_mforward: no rte s %s g %s\n",
1117 			    ip6_sprintf(&ip6->ip6_src),
1118 			    ip6_sprintf(&ip6->ip6_dst));
1119 #endif
1120 
1121 		/*
1122 		 * Allocate mbufs early so that we don't do extra work if we
1123 		 * are just going to fail anyway.
1124 		 */
1125 		rte = (struct rtdetq *)malloc(sizeof(*rte), M_MRTABLE,
1126 					      M_NOWAIT);
1127 		if (rte == NULL) {
1128 			splx(s);
1129 			return ENOBUFS;
1130 		}
1131 		mb0 = m_copy(m, 0, M_COPYALL);
1132 		/*
1133 		 * Pullup packet header if needed before storing it,
1134 		 * as other references may modify it in the meantime.
1135 		 */
1136 		if (mb0 &&
1137 		    (M_READONLY(mb0) || mb0->m_len < sizeof(struct ip6_hdr)))
1138 			mb0 = m_pullup(mb0, sizeof(struct ip6_hdr));
1139 		if (mb0 == NULL) {
1140 			free(rte, M_MRTABLE);
1141 			splx(s);
1142 			return ENOBUFS;
1143 		}
1144 
1145 		/* is there an upcall waiting for this packet? */
1146 		hash = MF6CHASH(ip6->ip6_src, ip6->ip6_dst);
1147 		for (rt = mf6ctable[hash]; rt; rt = rt->mf6c_next) {
1148 			if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_src,
1149 					       &rt->mf6c_origin.sin6_addr) &&
1150 			    IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst,
1151 					       &rt->mf6c_mcastgrp.sin6_addr) &&
1152 			    (rt->mf6c_stall != NULL))
1153 				break;
1154 		}
1155 
1156 		if (rt == NULL) {
1157 			struct mrt6msg *im;
1158 			struct omrt6msg *oim;
1159 
1160 			/* no upcall, so make a new entry */
1161 			rt = (struct mf6c *)malloc(sizeof(*rt), M_MRTABLE,
1162 						  M_NOWAIT);
1163 			if (rt == NULL) {
1164 				free(rte, M_MRTABLE);
1165 				m_freem(mb0);
1166 				splx(s);
1167 				return ENOBUFS;
1168 			}
1169 			/*
1170 			 * Make a copy of the header to send to the user
1171 			 * level process
1172 			 */
1173 			mm = m_copy(mb0, 0, sizeof(struct ip6_hdr));
1174 
1175 			if (mm == NULL) {
1176 				free(rte, M_MRTABLE);
1177 				m_freem(mb0);
1178 				free(rt, M_MRTABLE);
1179 				splx(s);
1180 				return ENOBUFS;
1181 			}
1182 
1183 			/*
1184 			 * Send message to routing daemon
1185 			 */
1186 			sockaddr_in6_init(&sin6, &ip6->ip6_src, 0, 0, 0);
1187 
1188 			im = NULL;
1189 			oim = NULL;
1190 			switch (ip6_mrouter_ver) {
1191 			case MRT6_OINIT:
1192 				oim = mtod(mm, struct omrt6msg *);
1193 				oim->im6_msgtype = MRT6MSG_NOCACHE;
1194 				oim->im6_mbz = 0;
1195 				break;
1196 			case MRT6_INIT:
1197 				im = mtod(mm, struct mrt6msg *);
1198 				im->im6_msgtype = MRT6MSG_NOCACHE;
1199 				im->im6_mbz = 0;
1200 				break;
1201 			default:
1202 				free(rte, M_MRTABLE);
1203 				m_freem(mb0);
1204 				free(rt, M_MRTABLE);
1205 				splx(s);
1206 				return EINVAL;
1207 			}
1208 
1209 #ifdef MRT6DEBUG
1210 			if (mrt6debug & DEBUG_FORWARD)
1211 				log(LOG_DEBUG,
1212 				    "getting the iif info in the kernel\n");
1213 #endif
1214 
1215 			for (mifp = mif6table, mifi = 0;
1216 			     mifi < nummifs && mifp->m6_ifp != ifp;
1217 			     mifp++, mifi++)
1218 				;
1219 
1220 			switch (ip6_mrouter_ver) {
1221 			case MRT6_OINIT:
1222 				oim->im6_mif = mifi;
1223 				break;
1224 			case MRT6_INIT:
1225 				im->im6_mif = mifi;
1226 				break;
1227 			}
1228 
1229 			if (socket_send(ip6_mrouter, mm, &sin6) < 0) {
1230 				log(LOG_WARNING, "ip6_mforward: ip6_mrouter "
1231 				    "socket queue full\n");
1232 				mrt6stat.mrt6s_upq_sockfull++;
1233 				free(rte, M_MRTABLE);
1234 				m_freem(mb0);
1235 				free(rt, M_MRTABLE);
1236 				splx(s);
1237 				return ENOBUFS;
1238 			}
1239 
1240 			mrt6stat.mrt6s_upcalls++;
1241 
1242 			/* insert new entry at head of hash chain */
1243 			bzero(rt, sizeof(*rt));
1244 			sockaddr_in6_init(&rt->mf6c_origin, &ip6->ip6_src,
1245 			    0, 0, 0);
1246 			sockaddr_in6_init(&rt->mf6c_mcastgrp, &ip6->ip6_dst,
1247 			    0, 0, 0);
1248 			rt->mf6c_expire = UPCALL_EXPIRE;
1249 			n6expire[hash]++;
1250 			rt->mf6c_parent = MF6C_INCOMPLETE_PARENT;
1251 
1252 			/* link into table */
1253 			rt->mf6c_next  = mf6ctable[hash];
1254 			mf6ctable[hash] = rt;
1255 			/* Add this entry to the end of the queue */
1256 			rt->mf6c_stall = rte;
1257 		} else {
1258 			/* determine if q has overflowed */
1259 			struct rtdetq **p;
1260 			int npkts = 0;
1261 
1262 			for (p = &rt->mf6c_stall; *p != NULL; p = &(*p)->next)
1263 				if (++npkts > MAX_UPQ6) {
1264 					mrt6stat.mrt6s_upq_ovflw++;
1265 					free(rte, M_MRTABLE);
1266 					m_freem(mb0);
1267 					splx(s);
1268 					return 0;
1269 				}
1270 
1271 			/* Add this entry to the end of the queue */
1272 			*p = rte;
1273 		}
1274 
1275 		rte->next = NULL;
1276 		rte->m = mb0;
1277 		rte->ifp = ifp;
1278 #ifdef UPCALL_TIMING
1279 		rte->t = tp;
1280 #endif /* UPCALL_TIMING */
1281 
1282 		splx(s);
1283 
1284 		return 0;
1285 	}
1286 }
1287 
1288 /*
1289  * Clean up cache entries if upcalls are not serviced
1290  * Call from the Slow Timeout mechanism, every 0.25 seconds.
1291  */
1292 static void
1293 expire_upcalls(void *unused)
1294 {
1295 	struct rtdetq *rte;
1296 	struct mf6c *mfc, **nptr;
1297 	int i;
1298 
1299 	mutex_enter(softnet_lock);
1300 	KERNEL_LOCK(1, NULL);
1301 
1302 	for (i = 0; i < MF6CTBLSIZ; i++) {
1303 		if (n6expire[i] == 0)
1304 			continue;
1305 		nptr = &mf6ctable[i];
1306 		while ((mfc = *nptr) != NULL) {
1307 			rte = mfc->mf6c_stall;
1308 			/*
1309 			 * Skip real cache entries
1310 			 * Make sure it wasn't marked to not expire (shouldn't happen)
1311 			 * If it expires now
1312 			 */
1313 			if (rte != NULL &&
1314 			    mfc->mf6c_expire != 0 &&
1315 			    --mfc->mf6c_expire == 0) {
1316 #ifdef MRT6DEBUG
1317 				if (mrt6debug & DEBUG_EXPIRE)
1318 					log(LOG_DEBUG, "expire_upcalls: expiring (%s %s)\n",
1319 					    ip6_sprintf(&mfc->mf6c_origin.sin6_addr),
1320 					    ip6_sprintf(&mfc->mf6c_mcastgrp.sin6_addr));
1321 #endif
1322 				/*
1323 				 * drop all the packets
1324 				 * free the mbuf with the pkt, if, timing info
1325 				 */
1326 				do {
1327 					struct rtdetq *n = rte->next;
1328 					m_freem(rte->m);
1329 					free(rte, M_MRTABLE);
1330 					rte = n;
1331 				} while (rte != NULL);
1332 				mrt6stat.mrt6s_cache_cleanups++;
1333 				n6expire[i]--;
1334 
1335 				*nptr = mfc->mf6c_next;
1336 				free(mfc, M_MRTABLE);
1337 			} else {
1338 				nptr = &mfc->mf6c_next;
1339 			}
1340 		}
1341 	}
1342 	callout_reset(&expire_upcalls_ch, EXPIRE_TIMEOUT,
1343 	    expire_upcalls, NULL);
1344 
1345 	KERNEL_UNLOCK_ONE(NULL);
1346 	mutex_exit(softnet_lock);
1347 }
1348 
1349 /*
1350  * Packet forwarding routine once entry in the cache is made
1351  */
1352 static int
1353 ip6_mdq(struct mbuf *m, struct ifnet *ifp, struct mf6c *rt)
1354 {
1355 	struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1356 	mifi_t mifi, iif;
1357 	struct mif6 *mifp;
1358 	int plen = m->m_pkthdr.len;
1359 	struct in6_addr src0, dst0; /* copies for local work */
1360 	u_int32_t iszone, idzone, oszone, odzone;
1361 	int error = 0;
1362 
1363 /*
1364  * Macro to send packet on mif.  Since RSVP packets don't get counted on
1365  * input, they shouldn't get counted on output, so statistics keeping is
1366  * separate.
1367  */
1368 
1369 #define MC6_SEND(ip6, mifp, m) do {				\
1370 	if ((mifp)->m6_flags & MIFF_REGISTER)			\
1371 		register_send((ip6), (mifp), (m));		\
1372 	else							\
1373 		phyint_send((ip6), (mifp), (m));		\
1374 } while (/*CONSTCOND*/ 0)
1375 
1376 	/*
1377 	 * Don't forward if it didn't arrive from the parent mif
1378 	 * for its origin.
1379 	 */
1380 	mifi = rt->mf6c_parent;
1381 	if ((mifi >= nummifs) || (mif6table[mifi].m6_ifp != ifp)) {
1382 		/* came in the wrong interface */
1383 #ifdef MRT6DEBUG
1384 		if (mrt6debug & DEBUG_FORWARD)
1385 			log(LOG_DEBUG,
1386 			    "wrong if: ifid %d mifi %d mififid %x\n",
1387 			    ifp->if_index, mifi,
1388 			    mif6table[mifi].m6_ifp ?
1389 			    mif6table[mifi].m6_ifp->if_index : -1);
1390 #endif
1391 		mrt6stat.mrt6s_wrong_if++;
1392 		rt->mf6c_wrong_if++;
1393 		/*
1394 		 * If we are doing PIM processing, and we are forwarding
1395 		 * packets on this interface, send a message to the
1396 		 * routing daemon.
1397 		 */
1398 		/* have to make sure this is a valid mif */
1399 		if (mifi < nummifs && mif6table[mifi].m6_ifp)
1400 			if (pim6 && (m->m_flags & M_LOOP) == 0) {
1401 				/*
1402 				 * Check the M_LOOP flag to avoid an
1403 				 * unnecessary PIM assert.
1404 				 * XXX: M_LOOP is an ad-hoc hack...
1405 				 */
1406 				struct sockaddr_in6 sin6;
1407 
1408 				struct mbuf *mm;
1409 				struct mrt6msg *im;
1410 				struct omrt6msg *oim;
1411 
1412 				mm = m_copy(m, 0, sizeof(struct ip6_hdr));
1413 				if (mm &&
1414 				    (M_READONLY(mm) ||
1415 				     mm->m_len < sizeof(struct ip6_hdr)))
1416 					mm = m_pullup(mm, sizeof(struct ip6_hdr));
1417 				if (mm == NULL)
1418 					return ENOBUFS;
1419 
1420 				oim = NULL;
1421 				im = NULL;
1422 				switch (ip6_mrouter_ver) {
1423 				case MRT6_OINIT:
1424 					oim = mtod(mm, struct omrt6msg *);
1425 					oim->im6_msgtype = MRT6MSG_WRONGMIF;
1426 					oim->im6_mbz = 0;
1427 					break;
1428 				case MRT6_INIT:
1429 					im = mtod(mm, struct mrt6msg *);
1430 					im->im6_msgtype = MRT6MSG_WRONGMIF;
1431 					im->im6_mbz = 0;
1432 					break;
1433 				default:
1434 					m_freem(mm);
1435 					return EINVAL;
1436 				}
1437 
1438 				for (mifp = mif6table, iif = 0;
1439 				     iif < nummifs && mifp &&
1440 					     mifp->m6_ifp != ifp;
1441 				     mifp++, iif++)
1442 					;
1443 
1444 				bzero(&sin6, sizeof(sin6));
1445 				sin6.sin6_len = sizeof(sin6);
1446 				sin6.sin6_family = AF_INET6;
1447 				switch (ip6_mrouter_ver) {
1448 				case MRT6_OINIT:
1449 					oim->im6_mif = iif;
1450 					sin6.sin6_addr = oim->im6_src;
1451 					break;
1452 				case MRT6_INIT:
1453 					im->im6_mif = iif;
1454 					sin6.sin6_addr = im->im6_src;
1455 					break;
1456 				}
1457 
1458 				mrt6stat.mrt6s_upcalls++;
1459 
1460 				if (socket_send(ip6_mrouter, mm, &sin6) < 0) {
1461 #ifdef MRT6DEBUG
1462 					if (mrt6debug)
1463 						log(LOG_WARNING, "mdq, ip6_mrouter socket queue full\n");
1464 #endif
1465 					++mrt6stat.mrt6s_upq_sockfull;
1466 					return ENOBUFS;
1467 				}	/* if socket Q full */
1468 			}		/* if PIM */
1469 		return 0;
1470 	}			/* if wrong iif */
1471 
1472 	/* If I sourced this packet, it counts as output, else it was input. */
1473 	if (m->m_pkthdr.rcvif == NULL) {
1474 		/* XXX: is rcvif really NULL when output?? */
1475 		mif6table[mifi].m6_pkt_out++;
1476 		mif6table[mifi].m6_bytes_out += plen;
1477 	} else {
1478 		mif6table[mifi].m6_pkt_in++;
1479 		mif6table[mifi].m6_bytes_in += plen;
1480 	}
1481 	rt->mf6c_pkt_cnt++;
1482 	rt->mf6c_byte_cnt += plen;
1483 
1484 	/*
1485 	 * For each mif, forward a copy of the packet if there are group
1486 	 * members downstream on the interface.
1487 	 */
1488 	src0 = ip6->ip6_src;
1489 	dst0 = ip6->ip6_dst;
1490 	if ((error = in6_setscope(&src0, ifp, &iszone)) != 0 ||
1491 	    (error = in6_setscope(&dst0, ifp, &idzone)) != 0) {
1492 		IP6_STATINC(IP6_STAT_BADSCOPE);
1493 		return (error);
1494 	}
1495 	for (mifp = mif6table, mifi = 0; mifi < nummifs; mifp++, mifi++)
1496 		if (IF_ISSET(mifi, &rt->mf6c_ifset)) {
1497 			if (mif6table[mifi].m6_ifp == NULL)
1498 				continue;
1499 			/*
1500 			 * check if the outgoing packet is going to break
1501 			 * a scope boundary.
1502 			 * XXX: For packets through PIM register tunnel
1503 			 * interface, we believe the routing daemon.
1504 			 */
1505 			if ((mif6table[rt->mf6c_parent].m6_flags &
1506 			     MIFF_REGISTER) == 0 &&
1507 			    (mif6table[mifi].m6_flags & MIFF_REGISTER) == 0) {
1508 				if (in6_setscope(&src0, mif6table[mifi].m6_ifp,
1509 				    &oszone) ||
1510 				    in6_setscope(&dst0, mif6table[mifi].m6_ifp,
1511 				    &odzone) ||
1512 				    iszone != oszone || idzone != odzone) {
1513 					IP6_STATINC(IP6_STAT_BADSCOPE);
1514 					continue;
1515 				}
1516 			}
1517 
1518 			mifp->m6_pkt_out++;
1519 			mifp->m6_bytes_out += plen;
1520 			MC6_SEND(ip6, mifp, m);
1521 		}
1522 	return 0;
1523 }
1524 
1525 static void
1526 phyint_send(struct ip6_hdr *ip6, struct mif6 *mifp, struct mbuf *m)
1527 {
1528 	struct mbuf *mb_copy;
1529 	struct ifnet *ifp = mifp->m6_ifp;
1530 	int error = 0;
1531 	int s;
1532 	static struct route ro;
1533 	struct in6_multi *in6m;
1534 	struct sockaddr_in6 dst6;
1535 	u_long linkmtu;
1536 
1537 	s = splsoftnet();
1538 	/*
1539 	 * Make a new reference to the packet; make sure that
1540 	 * the IPv6 header is actually copied, not just referenced,
1541 	 * so that ip6_output() only scribbles on the copy.
1542 	 */
1543 	mb_copy = m_copy(m, 0, M_COPYALL);
1544 	if (mb_copy &&
1545 	    (M_READONLY(mb_copy) || mb_copy->m_len < sizeof(struct ip6_hdr)))
1546 		mb_copy = m_pullup(mb_copy, sizeof(struct ip6_hdr));
1547 	if (mb_copy == NULL) {
1548 		splx(s);
1549 		return;
1550 	}
1551 	/* set MCAST flag to the outgoing packet */
1552 	mb_copy->m_flags |= M_MCAST;
1553 
1554 	/*
1555 	 * If we sourced the packet, call ip6_output since we may divide
1556 	 * the packet into fragments when the packet is too big for the
1557 	 * outgoing interface.
1558 	 * Otherwise, we can simply send the packet to the interface
1559 	 * sending queue.
1560 	 */
1561 	if (m->m_pkthdr.rcvif == NULL) {
1562 		struct ip6_moptions im6o;
1563 
1564 		im6o.im6o_multicast_ifp = ifp;
1565 		/* XXX: ip6_output will override ip6->ip6_hlim */
1566 		im6o.im6o_multicast_hlim = ip6->ip6_hlim;
1567 		im6o.im6o_multicast_loop = 1;
1568 		error = ip6_output(mb_copy, NULL, &ro, IPV6_FORWARDING,
1569 				   &im6o, NULL, NULL);
1570 
1571 #ifdef MRT6DEBUG
1572 		if (mrt6debug & DEBUG_XMIT)
1573 			log(LOG_DEBUG, "phyint_send on mif %d err %d\n",
1574 			    mifp - mif6table, error);
1575 #endif
1576 		splx(s);
1577 		return;
1578 	}
1579 
1580 	/*
1581 	 * If we belong to the destination multicast group
1582 	 * on the outgoing interface, loop back a copy.
1583 	 */
1584 	/*
1585 	 * Does not have to check source info, as it's alreay covered by
1586 	 * ip6_input
1587 	 */
1588 	sockaddr_in6_init(&dst6, &ip6->ip6_dst, 0, 0, 0);
1589 
1590 	IN6_LOOKUP_MULTI(ip6->ip6_dst, ifp, in6m);
1591 	if (in6m != NULL) {
1592 		ip6_mloopback(ifp, m,
1593 		    satocsin6(rtcache_getdst(&ro)));
1594 	}
1595 
1596 	/*
1597 	 * Put the packet into the sending queue of the outgoing interface
1598 	 * if it would fit in the MTU of the interface.
1599 	 */
1600 	linkmtu = IN6_LINKMTU(ifp);
1601 	if (mb_copy->m_pkthdr.len <= linkmtu || linkmtu < IPV6_MMTU) {
1602 		/*
1603 		 * We could call if_output directly here, but we use
1604 		 * nd6_output on purpose to see if IPv6 operation is allowed
1605 		 * on the interface.
1606 		 */
1607 		error = nd6_output(ifp, ifp, mb_copy, &dst6, NULL);
1608 #ifdef MRT6DEBUG
1609 		if (mrt6debug & DEBUG_XMIT)
1610 			log(LOG_DEBUG, "phyint_send on mif %d err %d\n",
1611 			    mifp - mif6table, error);
1612 #endif
1613 	} else {
1614 		/*
1615 		 * pMTU discovery is intentionally disabled by default, since
1616 		 * various router may notify pMTU in multicast, which can be
1617 		 * a DDoS to a router
1618 		 */
1619 		if (ip6_mcast_pmtu)
1620 			icmp6_error(mb_copy, ICMP6_PACKET_TOO_BIG, 0, linkmtu);
1621 		else {
1622 #ifdef MRT6DEBUG
1623 			if (mrt6debug & DEBUG_XMIT)
1624 				log(LOG_DEBUG,
1625 				    "phyint_send: packet too big on %s o %s g %s"
1626 				    " size %d(discarded)\n",
1627 				    if_name(ifp),
1628 				    ip6_sprintf(&ip6->ip6_src),
1629 				    ip6_sprintf(&ip6->ip6_dst),
1630 				    mb_copy->m_pkthdr.len);
1631 #endif /* MRT6DEBUG */
1632 			m_freem(mb_copy); /* simply discard the packet */
1633 		}
1634 	}
1635 
1636 	splx(s);
1637 }
1638 
1639 static int
1640 register_send(struct ip6_hdr *ip6, struct mif6 *mif, struct mbuf *m)
1641 {
1642 	struct mbuf *mm;
1643 	int i, len = m->m_pkthdr.len;
1644 	struct sockaddr_in6 sin6;
1645 	struct mrt6msg *im6;
1646 
1647 #ifdef MRT6DEBUG
1648 	if (mrt6debug)
1649 		log(LOG_DEBUG, "** IPv6 register_send **\n src %s dst %s\n",
1650 		    ip6_sprintf(&ip6->ip6_src), ip6_sprintf(&ip6->ip6_dst));
1651 #endif
1652 	PIM6_STATINC(PIM6_STAT_SND_REGISTERS);
1653 
1654 	/* Make a copy of the packet to send to the user level process */
1655 	MGETHDR(mm, M_DONTWAIT, MT_HEADER);
1656 	if (mm == NULL)
1657 		return ENOBUFS;
1658 	mm->m_data += max_linkhdr;
1659 	mm->m_len = sizeof(struct ip6_hdr);
1660 
1661 	if ((mm->m_next = m_copy(m, 0, M_COPYALL)) == NULL) {
1662 		m_freem(mm);
1663 		return ENOBUFS;
1664 	}
1665 	i = MHLEN - M_LEADINGSPACE(mm);
1666 	if (i > len)
1667 		i = len;
1668 	mm = m_pullup(mm, i);
1669 	if (mm == NULL)
1670 		return ENOBUFS;
1671 /* TODO: check it! */
1672 	mm->m_pkthdr.len = len + sizeof(struct ip6_hdr);
1673 
1674 	/*
1675 	 * Send message to routing daemon
1676 	 */
1677 	sockaddr_in6_init(&sin6, &ip6->ip6_src, 0, 0, 0);
1678 
1679 	im6 = mtod(mm, struct mrt6msg *);
1680 	im6->im6_msgtype      = MRT6MSG_WHOLEPKT;
1681 	im6->im6_mbz          = 0;
1682 
1683 	im6->im6_mif = mif - mif6table;
1684 
1685 	/* iif info is not given for reg. encap.n */
1686 	mrt6stat.mrt6s_upcalls++;
1687 
1688 	if (socket_send(ip6_mrouter, mm, &sin6) < 0) {
1689 #ifdef MRT6DEBUG
1690 		if (mrt6debug)
1691 			log(LOG_WARNING,
1692 			    "register_send: ip6_mrouter socket queue full\n");
1693 #endif
1694 		++mrt6stat.mrt6s_upq_sockfull;
1695 		return ENOBUFS;
1696 	}
1697 	return 0;
1698 }
1699 
1700 /*
1701  * PIM sparse mode hook
1702  * Receives the pim control messages, and passes them up to the listening
1703  * socket, using rip6_input.
1704  * The only message processed is the REGISTER pim message; the pim header
1705  * is stripped off, and the inner packet is passed to register_mforward.
1706  */
1707 int
1708 pim6_input(struct mbuf **mp, int *offp, int proto)
1709 {
1710 	struct pim *pim; /* pointer to a pim struct */
1711 	struct ip6_hdr *ip6;
1712 	int pimlen;
1713 	struct mbuf *m = *mp;
1714 	int minlen;
1715 	int off = *offp;
1716 
1717 	PIM6_STATINC(PIM6_STAT_RCV_TOTAL);
1718 
1719 	ip6 = mtod(m, struct ip6_hdr *);
1720 	pimlen = m->m_pkthdr.len - *offp;
1721 
1722 	/*
1723 	 * Validate lengths
1724 	 */
1725 	if (pimlen < PIM_MINLEN) {
1726 		PIM6_STATINC(PIM6_STAT_RCV_TOOSHORT);
1727 #ifdef MRT6DEBUG
1728 		if (mrt6debug & DEBUG_PIM)
1729 			log(LOG_DEBUG,"pim6_input: PIM packet too short\n");
1730 #endif
1731 		m_freem(m);
1732 		return (IPPROTO_DONE);
1733 	}
1734 
1735 	/*
1736 	 * if the packet is at least as big as a REGISTER, go ahead
1737 	 * and grab the PIM REGISTER header size, to avoid another
1738 	 * possible m_pullup() later.
1739 	 *
1740 	 * PIM_MINLEN       == pimhdr + u_int32 == 8
1741 	 * PIM6_REG_MINLEN   == pimhdr + reghdr + eip6hdr == 4 + 4 + 40
1742 	 */
1743 	minlen = (pimlen >= PIM6_REG_MINLEN) ? PIM6_REG_MINLEN : PIM_MINLEN;
1744 
1745 	/*
1746 	 * Make sure that the IP6 and PIM headers in contiguous memory, and
1747 	 * possibly the PIM REGISTER header
1748 	 */
1749 	IP6_EXTHDR_GET(pim, struct pim *, m, off, minlen);
1750 	if (pim == NULL) {
1751 		PIM6_STATINC(PIM6_STAT_RCV_TOOSHORT);
1752 		return IPPROTO_DONE;
1753 	}
1754 
1755 	/* PIM version check */
1756 	if (pim->pim_ver != PIM_VERSION) {
1757 		PIM6_STATINC(PIM6_STAT_RCV_BADVERSION);
1758 #ifdef MRT6DEBUG
1759 		log(LOG_ERR,
1760 		    "pim6_input: incorrect version %d, expecting %d\n",
1761 		    pim->pim_ver, PIM_VERSION);
1762 #endif
1763 		m_freem(m);
1764 		return (IPPROTO_DONE);
1765 	}
1766 
1767 #define PIM6_CHECKSUM
1768 #ifdef PIM6_CHECKSUM
1769 	{
1770 		int cksumlen;
1771 
1772 		/*
1773 		 * Validate checksum.
1774 		 * If PIM REGISTER, exclude the data packet
1775 		 */
1776 		if (pim->pim_type == PIM_REGISTER)
1777 			cksumlen = PIM_MINLEN;
1778 		else
1779 			cksumlen = pimlen;
1780 
1781 		if (in6_cksum(m, IPPROTO_PIM, off, cksumlen)) {
1782 			PIM6_STATINC(PIM6_STAT_RCV_BADSUM);
1783 #ifdef MRT6DEBUG
1784 			if (mrt6debug & DEBUG_PIM)
1785 				log(LOG_DEBUG,
1786 				    "pim6_input: invalid checksum\n");
1787 #endif
1788 			m_freem(m);
1789 			return (IPPROTO_DONE);
1790 		}
1791 	}
1792 #endif /* PIM_CHECKSUM */
1793 
1794 	if (pim->pim_type == PIM_REGISTER) {
1795 		/*
1796 		 * since this is a REGISTER, we'll make a copy of the register
1797 		 * headers ip6+pim+u_int32_t+encap_ip6, to be passed up to the
1798 		 * routing daemon.
1799 		 */
1800 		static const struct sockaddr_in6 dst = {
1801 			.sin6_len = sizeof(dst),
1802 			.sin6_family = AF_INET6,
1803 		};
1804 
1805 		struct mbuf *mcp;
1806 		struct ip6_hdr *eip6;
1807 		u_int32_t *reghdr;
1808 
1809 		PIM6_STATINC(PIM6_STAT_RCV_REGISTERS);
1810 
1811 		if ((reg_mif_num >= nummifs) || (reg_mif_num == (mifi_t) -1)) {
1812 #ifdef MRT6DEBUG
1813 			if (mrt6debug & DEBUG_PIM)
1814 				log(LOG_DEBUG,
1815 				    "pim6_input: register mif not set: %d\n",
1816 				    reg_mif_num);
1817 #endif
1818 			m_freem(m);
1819 			return (IPPROTO_DONE);
1820 		}
1821 
1822 		reghdr = (u_int32_t *)(pim + 1);
1823 
1824 		if ((ntohl(*reghdr) & PIM_NULL_REGISTER))
1825 			goto pim6_input_to_daemon;
1826 
1827 		/*
1828 		 * Validate length
1829 		 */
1830 		if (pimlen < PIM6_REG_MINLEN) {
1831 			PIM6_STATINC(PIM6_STAT_RCV_TOOSHORT);
1832 			PIM6_STATINC(PIM6_STAT_RCV_BADREGISTERS);
1833 #ifdef MRT6DEBUG
1834 			log(LOG_ERR,
1835 			    "pim6_input: register packet size too "
1836 			    "small %d from %s\n",
1837 			    pimlen, ip6_sprintf(&ip6->ip6_src));
1838 #endif
1839 			m_freem(m);
1840 			return (IPPROTO_DONE);
1841 		}
1842 
1843 		eip6 = (struct ip6_hdr *) (reghdr + 1);
1844 #ifdef MRT6DEBUG
1845 		if (mrt6debug & DEBUG_PIM)
1846 			log(LOG_DEBUG,
1847 			    "pim6_input[register], eip6: %s -> %s, "
1848 			    "eip6 plen %d\n",
1849 			    ip6_sprintf(&eip6->ip6_src),
1850 			    ip6_sprintf(&eip6->ip6_dst),
1851 			    ntohs(eip6->ip6_plen));
1852 #endif
1853 
1854 		/* verify the version number of the inner packet */
1855 		if ((eip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
1856 			PIM6_STATINC(PIM6_STAT_RCV_BADREGISTERS);
1857 #ifdef MRT6DEBUG
1858 			log(LOG_DEBUG, "pim6_input: invalid IP version (%d) "
1859 			    "of the inner packet\n",
1860 			    (eip6->ip6_vfc & IPV6_VERSION));
1861 #endif
1862 			m_freem(m);
1863 			return (IPPROTO_NONE);
1864 		}
1865 
1866 		/* verify the inner packet is destined to a mcast group */
1867 		if (!IN6_IS_ADDR_MULTICAST(&eip6->ip6_dst)) {
1868 			PIM6_STATINC(PIM6_STAT_RCV_BADREGISTERS);
1869 #ifdef MRT6DEBUG
1870 			if (mrt6debug & DEBUG_PIM)
1871 				log(LOG_DEBUG,
1872 				    "pim6_input: inner packet of register "
1873 				    "is not multicast %s\n",
1874 				    ip6_sprintf(&eip6->ip6_dst));
1875 #endif
1876 			m_freem(m);
1877 			return (IPPROTO_DONE);
1878 		}
1879 
1880 		/*
1881 		 * make a copy of the whole header to pass to the daemon later.
1882 		 */
1883 		mcp = m_copy(m, 0, off + PIM6_REG_MINLEN);
1884 		if (mcp == NULL) {
1885 #ifdef MRT6DEBUG
1886 			log(LOG_ERR,
1887 			    "pim6_input: pim register: "
1888 			    "could not copy register head\n");
1889 #endif
1890 			m_freem(m);
1891 			return (IPPROTO_DONE);
1892 		}
1893 
1894 		/*
1895 		 * forward the inner ip6 packet; point m_data at the inner ip6.
1896 		 */
1897 		m_adj(m, off + PIM_MINLEN);
1898 #ifdef MRT6DEBUG
1899 		if (mrt6debug & DEBUG_PIM) {
1900 			log(LOG_DEBUG,
1901 			    "pim6_input: forwarding decapsulated register: "
1902 			    "src %s, dst %s, mif %d\n",
1903 			    ip6_sprintf(&eip6->ip6_src),
1904 			    ip6_sprintf(&eip6->ip6_dst),
1905 			    reg_mif_num);
1906 		}
1907 #endif
1908 
1909 		looutput(mif6table[reg_mif_num].m6_ifp, m,
1910 			      (struct sockaddr *)__UNCONST(&dst),
1911 			      (struct rtentry *) NULL);
1912 
1913 		/* prepare the register head to send to the mrouting daemon */
1914 		m = mcp;
1915 	}
1916 
1917 	/*
1918 	 * Pass the PIM message up to the daemon; if it is a register message
1919 	 * pass the 'head' only up to the daemon. This includes the
1920 	 * encapsulator ip6 header, pim header, register header and the
1921 	 * encapsulated ip6 header.
1922 	 */
1923   pim6_input_to_daemon:
1924 	rip6_input(&m, offp, proto);
1925 	return (IPPROTO_DONE);
1926 }
1927 
1928 static int
1929 sysctl_net_inet6_pim6_stats(SYSCTLFN_ARGS)
1930 {
1931 
1932 	return (NETSTAT_SYSCTL(pim6stat_percpu, PIM6_NSTATS));
1933 }
1934 
1935 SYSCTL_SETUP(sysctl_net_inet6_pim6_setup, "sysctl net.inet6.pim6 subtree setup")
1936 {
1937 	sysctl_createv(clog, 0, NULL, NULL,
1938 		       CTLFLAG_PERMANENT,
1939 		       CTLTYPE_NODE, "net", NULL,
1940 		       NULL, 0, NULL, 0,
1941 		       CTL_NET, CTL_EOL);
1942 	sysctl_createv(clog, 0, NULL, NULL,
1943 		       CTLFLAG_PERMANENT,
1944 		       CTLTYPE_NODE, "inet6", NULL,
1945 		       NULL, 0, NULL, 0,
1946 		       CTL_NET, PF_INET6, CTL_EOL);
1947 	sysctl_createv(clog, 0, NULL, NULL,
1948 		       CTLFLAG_PERMANENT,
1949 		       CTLTYPE_NODE, "pim6",
1950 		       SYSCTL_DESCR("PIMv6 settings"),
1951 		       NULL, 0, NULL, 0,
1952 		       CTL_NET, PF_INET6, IPPROTO_PIM, CTL_EOL);
1953 
1954 	sysctl_createv(clog, 0, NULL, NULL,
1955 		       CTLFLAG_PERMANENT,
1956 		       CTLTYPE_STRUCT, "stats",
1957 		       SYSCTL_DESCR("PIMv6 statistics"),
1958 		       sysctl_net_inet6_pim6_stats, 0, NULL, 0,
1959 		       CTL_NET, PF_INET6, IPPROTO_PIM, PIM6CTL_STATS,
1960 		       CTL_EOL);
1961 }
1962