xref: /freebsd/sys/netinet6/ip6_mroute.c (revision 35a04710d7286aa9538917fd7f8e417dbee95b82)
1 /*	$FreeBSD$	*/
2 /*	$KAME: ip6_mroute.c,v 1.58 2001/12/18 02:36:31 itojun 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) 1989 Stephen Deering
37  * Copyright (c) 1992, 1993
38  *      The Regents of the University of California.  All rights reserved.
39  *
40  * This code is derived from software contributed to Berkeley by
41  * Stephen Deering of Stanford University.
42  *
43  * Redistribution and use in source and binary forms, with or without
44  * modification, are permitted provided that the following conditions
45  * are met:
46  * 1. Redistributions of source code must retain the above copyright
47  *    notice, this list of conditions and the following disclaimer.
48  * 2. Redistributions in binary form must reproduce the above copyright
49  *    notice, this list of conditions and the following disclaimer in the
50  *    documentation and/or other materials provided with the distribution.
51  * 4. Neither the name of the University nor the names of its contributors
52  *    may be used to endorse or promote products derived from this software
53  *    without specific prior written permission.
54  *
55  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
56  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
57  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
58  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
59  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
60  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
61  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
62  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
63  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
64  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
65  * SUCH DAMAGE.
66  *
67  *      @(#)ip_mroute.c 8.2 (Berkeley) 11/15/93
68  */
69 
70 /*
71  * IP multicast forwarding procedures
72  *
73  * Written by David Waitzman, BBN Labs, August 1988.
74  * Modified by Steve Deering, Stanford, February 1989.
75  * Modified by Mark J. Steiglitz, Stanford, May, 1991
76  * Modified by Van Jacobson, LBL, January 1993
77  * Modified by Ajit Thyagarajan, PARC, August 1993
78  * Modified by Bill Fenner, PARC, April 1994
79  *
80  * MROUTING Revision: 3.5.1.2 + PIM-SMv2 (pimd) Support
81  */
82 
83 #include "opt_inet.h"
84 #include "opt_inet6.h"
85 
86 #include <sys/param.h>
87 #include <sys/callout.h>
88 #include <sys/errno.h>
89 #include <sys/kernel.h>
90 #include <sys/lock.h>
91 #include <sys/malloc.h>
92 #include <sys/mbuf.h>
93 #include <sys/protosw.h>
94 #include <sys/signalvar.h>
95 #include <sys/socket.h>
96 #include <sys/socketvar.h>
97 #include <sys/sockio.h>
98 #include <sys/sx.h>
99 #include <sys/sysctl.h>
100 #include <sys/syslog.h>
101 #include <sys/systm.h>
102 #include <sys/time.h>
103 
104 #include <net/if.h>
105 #include <net/if_types.h>
106 #include <net/raw_cb.h>
107 #include <net/route.h>
108 
109 #include <netinet/in.h>
110 #include <netinet/in_var.h>
111 #include <netinet/icmp6.h>
112 
113 #include <netinet/ip6.h>
114 #include <netinet6/ip6_var.h>
115 #include <netinet6/scope6_var.h>
116 #include <netinet6/nd6.h>
117 #include <netinet6/ip6_mroute.h>
118 #include <netinet6/ip6protosw.h>
119 #include <netinet6/pim6.h>
120 #include <netinet6/pim6_var.h>
121 
122 static MALLOC_DEFINE(M_MRTABLE6, "mf6c", "multicast forwarding cache entry");
123 
124 /* XXX: this is a very common idiom; move to <sys/mbuf.h> ? */
125 #define M_HASCL(m) ((m)->m_flags & M_EXT)
126 
127 static int ip6_mdq __P((struct mbuf *, struct ifnet *, struct mf6c *));
128 static void phyint_send __P((struct ip6_hdr *, struct mif6 *, struct mbuf *));
129 
130 static int set_pim6 __P((int *));
131 static int socket_send __P((struct socket *, struct mbuf *,
132 	    struct sockaddr_in6 *));
133 static int register_send __P((struct ip6_hdr *, struct mif6 *,
134 	    struct mbuf *));
135 
136 extern struct domain inet6domain;
137 
138 /* XXX: referenced from ip_mroute.c for dynamically loading this code. */
139 struct ip6protosw in6_pim_protosw = {
140 	.pr_type =		SOCK_RAW,
141 	.pr_domain =		&inet6domain,
142 	.pr_protocol =		IPPROTO_PIM,
143 	.pr_flags =		PR_ATOMIC|PR_ADDR|PR_LASTHDR,
144 	.pr_input =		pim6_input,
145 	.pr_output =		rip6_output,
146 	.pr_ctloutput =		rip6_ctloutput,
147 	.pr_usrreqs =		&rip6_usrreqs
148 };
149 
150 static int ip6_mrouter_ver = 0;
151 
152 SYSCTL_DECL(_net_inet6);
153 SYSCTL_DECL(_net_inet6_ip6);
154 SYSCTL_NODE(_net_inet6, IPPROTO_PIM, pim, CTLFLAG_RW, 0, "PIM");
155 
156 static struct mrt6stat mrt6stat;
157 SYSCTL_STRUCT(_net_inet6_ip6, OID_AUTO, mrt6stat, CTLFLAG_RW,
158     &mrt6stat, mrt6stat,
159     "Multicast Routing Statistics (struct mrt6stat, netinet6/ip6_mroute.h)");
160 
161 #define NO_RTE_FOUND	0x1
162 #define RTE_FOUND	0x2
163 
164 static struct mf6c *mf6ctable[MF6CTBLSIZ];
165 SYSCTL_OPAQUE(_net_inet6_ip6, OID_AUTO, mf6ctable, CTLFLAG_RD,
166     &mf6ctable, sizeof(mf6ctable), "S,*mf6ctable[MF6CTBLSIZ]",
167     "Multicast Forwarding Table (struct *mf6ctable[MF6CTBLSIZ], "
168     "netinet6/ip6_mroute.h)");
169 
170 static u_char n6expire[MF6CTBLSIZ];
171 
172 static struct mif6 mif6table[MAXMIFS];
173 SYSCTL_OPAQUE(_net_inet6_ip6, OID_AUTO, mif6table, CTLFLAG_RD,
174     &mif6table, sizeof(mif6table), "S,vif[MAXMIFS]",
175     "Multicast Interfaces (struct mif[MAXMIFS], netinet6/ip6_mroute.h)");
176 
177 #ifdef MRT6DEBUG
178 static u_int mrt6debug = 0;		/* debug level */
179 #define DEBUG_MFC	0x02
180 #define DEBUG_FORWARD	0x04
181 #define DEBUG_EXPIRE	0x08
182 #define DEBUG_XMIT	0x10
183 #define DEBUG_REG	0x20
184 #define DEBUG_PIM	0x40
185 #endif
186 
187 static void	expire_upcalls __P((void *));
188 #define	EXPIRE_TIMEOUT	(hz / 4)	/* 4x / second */
189 #define	UPCALL_EXPIRE	6		/* number of timeouts */
190 
191 #ifdef INET
192 #ifdef MROUTING
193 extern struct socket *ip_mrouter;
194 #endif
195 #endif
196 
197 /*
198  * 'Interfaces' associated with decapsulator (so we can tell
199  * packets that went through it from ones that get reflected
200  * by a broken gateway).  Different from IPv4 register_if,
201  * these interfaces are linked into the system ifnet list,
202  * because per-interface IPv6 statistics are maintained in
203  * ifp->if_afdata.  But it does not have any routes point
204  * to them.  I.e., packets can't be sent this way.  They
205  * only exist as a placeholder for multicast source
206  * verification.
207  */
208 static struct ifnet *multicast_register_if6;
209 
210 #define ENCAP_HOPS 64
211 
212 /*
213  * Private variables.
214  */
215 static mifi_t nummifs = 0;
216 static mifi_t reg_mif_num = (mifi_t)-1;
217 
218 static struct pim6stat pim6stat;
219 SYSCTL_STRUCT(_net_inet6_pim, PIM6CTL_STATS, stats, CTLFLAG_RD,
220     &pim6stat, pim6stat,
221     "PIM Statistics (struct pim6stat, netinet6/pim_var.h)");
222 
223 static int pim6;
224 
225 /*
226  * Hash function for a source, group entry
227  */
228 #define MF6CHASH(a, g) MF6CHASHMOD((a).s6_addr32[0] ^ (a).s6_addr32[1] ^ \
229 				   (a).s6_addr32[2] ^ (a).s6_addr32[3] ^ \
230 				   (g).s6_addr32[0] ^ (g).s6_addr32[1] ^ \
231 				   (g).s6_addr32[2] ^ (g).s6_addr32[3])
232 
233 /*
234  * Find a route for a given origin IPv6 address and Multicast group address.
235  */
236 #define MF6CFIND(o, g, rt) do { \
237 	struct mf6c *_rt = mf6ctable[MF6CHASH(o,g)]; \
238 	rt = NULL; \
239 	mrt6stat.mrt6s_mfc_lookups++; \
240 	while (_rt) { \
241 		if (IN6_ARE_ADDR_EQUAL(&_rt->mf6c_origin.sin6_addr, &(o)) && \
242 		    IN6_ARE_ADDR_EQUAL(&_rt->mf6c_mcastgrp.sin6_addr, &(g)) && \
243 		    (_rt->mf6c_stall == NULL)) { \
244 			rt = _rt; \
245 			break; \
246 		} \
247 		_rt = _rt->mf6c_next; \
248 	} \
249 	if (rt == NULL) { \
250 		mrt6stat.mrt6s_mfc_misses++; \
251 	} \
252 } while (/*CONSTCOND*/ 0)
253 
254 /*
255  * Macros to compute elapsed time efficiently
256  * Borrowed from Van Jacobson's scheduling code
257  * XXX: replace with timersub() ?
258  */
259 #define TV_DELTA(a, b, delta) do { \
260 	    int xxs; \
261 		\
262 	    delta = (a).tv_usec - (b).tv_usec; \
263 	    if ((xxs = (a).tv_sec - (b).tv_sec)) { \
264 	       switch (xxs) { \
265 		      case 2: \
266 			  delta += 1000000; \
267 			      /* FALLTHROUGH */ \
268 		      case 1: \
269 			  delta += 1000000; \
270 			  break; \
271 		      default: \
272 			  delta += (1000000 * xxs); \
273 	       } \
274 	    } \
275 } while (/*CONSTCOND*/ 0)
276 
277 /* XXX: replace with timercmp(a, b, <) ? */
278 #define TV_LT(a, b) (((a).tv_usec < (b).tv_usec && \
279 	      (a).tv_sec <= (b).tv_sec) || (a).tv_sec < (b).tv_sec)
280 
281 #ifdef UPCALL_TIMING
282 #define UPCALL_MAX	50
283 static u_long upcall_data[UPCALL_MAX + 1];
284 static void collate();
285 #endif /* UPCALL_TIMING */
286 
287 static int get_sg_cnt __P((struct sioc_sg_req6 *));
288 static int get_mif6_cnt __P((struct sioc_mif_req6 *));
289 static int ip6_mrouter_init __P((struct socket *, int, int));
290 static int add_m6if __P((struct mif6ctl *));
291 static int del_m6if __P((mifi_t *));
292 static int add_m6fc __P((struct mf6cctl *));
293 static int del_m6fc __P((struct mf6cctl *));
294 
295 static struct callout expire_upcalls_ch;
296 
297 int X_ip6_mforward(struct ip6_hdr *ip6, struct ifnet *ifp, struct mbuf *m);
298 int X_ip6_mrouter_done(void);
299 int X_ip6_mrouter_set(struct socket *so, struct sockopt *sopt);
300 int X_ip6_mrouter_get(struct socket *so, struct sockopt *sopt);
301 int X_mrt6_ioctl(int cmd, caddr_t data);
302 
303 /*
304  * Handle MRT setsockopt commands to modify the multicast routing tables.
305  */
306 int
307 X_ip6_mrouter_set(struct socket *so, struct sockopt *sopt)
308 {
309 	int error = 0;
310 	int optval;
311 	struct mif6ctl mifc;
312 	struct mf6cctl mfcc;
313 	mifi_t mifi;
314 
315 	if (so != ip6_mrouter && sopt->sopt_name != MRT6_INIT)
316 		return (EACCES);
317 
318 	switch (sopt->sopt_name) {
319 	case MRT6_INIT:
320 #ifdef MRT6_OINIT
321 	case MRT6_OINIT:
322 #endif
323 		error = sooptcopyin(sopt, &optval, sizeof(optval),
324 		    sizeof(optval));
325 		if (error)
326 			break;
327 		error = ip6_mrouter_init(so, optval, sopt->sopt_name);
328 		break;
329 	case MRT6_DONE:
330 		error = X_ip6_mrouter_done();
331 		break;
332 	case MRT6_ADD_MIF:
333 		error = sooptcopyin(sopt, &mifc, sizeof(mifc), sizeof(mifc));
334 		if (error)
335 			break;
336 		error = add_m6if(&mifc);
337 		break;
338 	case MRT6_ADD_MFC:
339 		error = sooptcopyin(sopt, &mfcc, sizeof(mfcc), sizeof(mfcc));
340 		if (error)
341 			break;
342 		error = add_m6fc(&mfcc);
343 		break;
344 	case MRT6_DEL_MFC:
345 		error = sooptcopyin(sopt, &mfcc, sizeof(mfcc), sizeof(mfcc));
346 		if (error)
347 			break;
348 		error = del_m6fc(&mfcc);
349 		break;
350 	case MRT6_DEL_MIF:
351 		error = sooptcopyin(sopt, &mifi, sizeof(mifi), sizeof(mifi));
352 		if (error)
353 			break;
354 		error = del_m6if(&mifi);
355 		break;
356 	case MRT6_PIM:
357 		error = sooptcopyin(sopt, &optval, sizeof(optval),
358 		    sizeof(optval));
359 		if (error)
360 			break;
361 		error = set_pim6(&optval);
362 		break;
363 	default:
364 		error = EOPNOTSUPP;
365 		break;
366 	}
367 
368 	return (error);
369 }
370 
371 /*
372  * Handle MRT getsockopt commands
373  */
374 int
375 X_ip6_mrouter_get(struct socket *so, struct sockopt *sopt)
376 {
377 	int error = 0;
378 
379 	if (so != ip6_mrouter)
380 		return (EACCES);
381 
382 	switch (sopt->sopt_name) {
383 		case MRT6_PIM:
384 			error = sooptcopyout(sopt, &pim6, sizeof(pim6));
385 			break;
386 	}
387 	return (error);
388 }
389 
390 /*
391  * Handle ioctl commands to obtain information from the cache
392  */
393 int
394 X_mrt6_ioctl(int cmd, caddr_t data)
395 {
396 	switch (cmd) {
397 	case SIOCGETSGCNT_IN6:
398 		return (get_sg_cnt((struct sioc_sg_req6 *)data));
399 	case SIOCGETMIFCNT_IN6:
400 		return (get_mif6_cnt((struct sioc_mif_req6 *)data));
401 	default:
402 		return (EINVAL);
403 	}
404 }
405 
406 /*
407  * returns the packet, byte, rpf-failure count for the source group provided
408  */
409 static int
410 get_sg_cnt(struct sioc_sg_req6 *req)
411 {
412 	struct mf6c *rt;
413 	int s;
414 
415 	s = splnet();
416 	MF6CFIND(req->src.sin6_addr, req->grp.sin6_addr, rt);
417 	splx(s);
418 	if (rt != NULL) {
419 		req->pktcnt = rt->mf6c_pkt_cnt;
420 		req->bytecnt = rt->mf6c_byte_cnt;
421 		req->wrong_if = rt->mf6c_wrong_if;
422 	} else
423 		return (ESRCH);
424 #if 0
425 		req->pktcnt = req->bytecnt = req->wrong_if = 0xffffffff;
426 #endif
427 
428 	return (0);
429 }
430 
431 /*
432  * returns the input and output packet and byte counts on the mif provided
433  */
434 static int
435 get_mif6_cnt(struct sioc_mif_req6 *req)
436 {
437 	mifi_t mifi = req->mifi;
438 
439 	if (mifi >= nummifs)
440 		return (EINVAL);
441 
442 	req->icount = mif6table[mifi].m6_pkt_in;
443 	req->ocount = mif6table[mifi].m6_pkt_out;
444 	req->ibytes = mif6table[mifi].m6_bytes_in;
445 	req->obytes = mif6table[mifi].m6_bytes_out;
446 
447 	return (0);
448 }
449 
450 static int
451 set_pim6(int *i)
452 {
453 	if ((*i != 1) && (*i != 0))
454 		return (EINVAL);
455 
456 	pim6 = *i;
457 
458 	return (0);
459 }
460 
461 /*
462  * Enable multicast routing
463  */
464 static int
465 ip6_mrouter_init(struct socket *so, int v, int cmd)
466 {
467 #ifdef MRT6DEBUG
468 	if (mrt6debug)
469 		log(LOG_DEBUG,
470 		    "ip6_mrouter_init: so_type = %d, pr_protocol = %d\n",
471 		    so->so_type, so->so_proto->pr_protocol);
472 #endif
473 
474 	if (so->so_type != SOCK_RAW ||
475 	    so->so_proto->pr_protocol != IPPROTO_ICMPV6)
476 		return (EOPNOTSUPP);
477 
478 	if (v != 1)
479 		return (ENOPROTOOPT);
480 
481 	if (ip6_mrouter != NULL)
482 		return (EADDRINUSE);
483 
484 	ip6_mrouter = so;
485 	ip6_mrouter_ver = cmd;
486 
487 	bzero((caddr_t)mf6ctable, sizeof(mf6ctable));
488 	bzero((caddr_t)n6expire, sizeof(n6expire));
489 
490 	pim6 = 0;/* used for stubbing out/in pim stuff */
491 
492 	callout_init(&expire_upcalls_ch, 0);
493 	callout_reset(&expire_upcalls_ch, EXPIRE_TIMEOUT,
494 	    expire_upcalls, NULL);
495 
496 #ifdef MRT6DEBUG
497 	if (mrt6debug)
498 		log(LOG_DEBUG, "ip6_mrouter_init\n");
499 #endif
500 
501 	return (0);
502 }
503 
504 /*
505  * Disable multicast routing
506  */
507 int
508 X_ip6_mrouter_done(void)
509 {
510 	mifi_t mifi;
511 	int i;
512 	struct mf6c *rt;
513 	struct rtdetq *rte;
514 	int s;
515 
516 	s = splnet();
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 				if_allmulti(mif6table[mifi].m6_ifp, 0);
538 			}
539 		}
540 	}
541 	bzero((caddr_t)mif6table, sizeof(mif6table));
542 	nummifs = 0;
543 
544 	pim6 = 0; /* used to stub out/in pim specific code */
545 
546 	callout_stop(&expire_upcalls_ch);
547 
548 	/*
549 	 * Free all multicast forwarding cache entries.
550 	 */
551 	for (i = 0; i < MF6CTBLSIZ; i++) {
552 		rt = mf6ctable[i];
553 		while (rt) {
554 			struct mf6c *frt;
555 
556 			for (rte = rt->mf6c_stall; rte != NULL; ) {
557 				struct rtdetq *n = rte->next;
558 
559 				m_free(rte->m);
560 				free(rte, M_MRTABLE6);
561 				rte = n;
562 			}
563 			frt = rt;
564 			rt = rt->mf6c_next;
565 			free(frt, M_MRTABLE6);
566 		}
567 	}
568 
569 	bzero((caddr_t)mf6ctable, sizeof(mf6ctable));
570 
571 	/*
572 	 * Reset register interface
573 	 */
574 	if (reg_mif_num != (mifi_t)-1 && multicast_register_if6 != NULL) {
575 		if_detach(multicast_register_if6);
576 		if_free(multicast_register_if6);
577 		reg_mif_num = (mifi_t)-1;
578 		multicast_register_if6 = NULL;
579 	}
580 
581 	ip6_mrouter = NULL;
582 	ip6_mrouter_ver = 0;
583 
584 	splx(s);
585 
586 #ifdef MRT6DEBUG
587 	if (mrt6debug)
588 		log(LOG_DEBUG, "ip6_mrouter_done\n");
589 #endif
590 
591 	return (0);
592 }
593 
594 static struct sockaddr_in6 sin6 = { sizeof(sin6), AF_INET6 };
595 
596 /*
597  * Add a mif to the mif table
598  */
599 static int
600 add_m6if(struct mif6ctl *mifcp)
601 {
602 	struct mif6 *mifp;
603 	struct ifnet *ifp;
604 	int error, s;
605 
606 	if (mifcp->mif6c_mifi >= MAXMIFS)
607 		return (EINVAL);
608 	mifp = mif6table + mifcp->mif6c_mifi;
609 	if (mifp->m6_ifp)
610 		return (EADDRINUSE); /* XXX: is it appropriate? */
611 	if (mifcp->mif6c_pifi == 0 || mifcp->mif6c_pifi > if_index)
612 		return (ENXIO);
613 	ifp = ifnet_byindex(mifcp->mif6c_pifi);
614 
615 	if (mifcp->mif6c_flags & MIFF_REGISTER) {
616 		if (reg_mif_num == (mifi_t)-1) {
617 			ifp = if_alloc(IFT_OTHER);
618 
619 			if_initname(ifp, "register_mif", 0);
620 			ifp->if_flags |= IFF_LOOPBACK;
621 			if_attach(ifp);
622 			multicast_register_if6 = ifp;
623 			reg_mif_num = mifcp->mif6c_mifi;
624 			/*
625 			 * it is impossible to guess the ifindex of the
626 			 * register interface.  So mif6c_pifi is automatically
627 			 * calculated.
628 			 */
629 			mifcp->mif6c_pifi = ifp->if_index;
630 		} else {
631 			ifp = multicast_register_if6;
632 		}
633 
634 	} /* if REGISTER */
635 	else {
636 		/* Make sure the interface supports multicast */
637 		if ((ifp->if_flags & IFF_MULTICAST) == 0)
638 			return (EOPNOTSUPP);
639 
640 		s = splnet();
641 		error = if_allmulti(ifp, 1);
642 		splx(s);
643 		if (error)
644 			return (error);
645 	}
646 
647 	s = splnet();
648 	mifp->m6_flags     = mifcp->mif6c_flags;
649 	mifp->m6_ifp       = ifp;
650 
651 	/* initialize per mif pkt counters */
652 	mifp->m6_pkt_in    = 0;
653 	mifp->m6_pkt_out   = 0;
654 	mifp->m6_bytes_in  = 0;
655 	mifp->m6_bytes_out = 0;
656 	splx(s);
657 
658 	/* Adjust nummifs up if the mifi is higher than nummifs */
659 	if (nummifs <= mifcp->mif6c_mifi)
660 		nummifs = mifcp->mif6c_mifi + 1;
661 
662 #ifdef MRT6DEBUG
663 	if (mrt6debug)
664 		log(LOG_DEBUG,
665 		    "add_mif #%d, phyint %s\n",
666 		    mifcp->mif6c_mifi,
667 		    ifp->if_xname);
668 #endif
669 
670 	return (0);
671 }
672 
673 /*
674  * Delete a mif from the mif table
675  */
676 static int
677 del_m6if(mifi_t *mifip)
678 {
679 	struct mif6 *mifp = mif6table + *mifip;
680 	mifi_t mifi;
681 	struct ifnet *ifp;
682 	int s;
683 
684 	if (*mifip >= nummifs)
685 		return (EINVAL);
686 	if (mifp->m6_ifp == NULL)
687 		return (EINVAL);
688 
689 	s = splnet();
690 
691 	if (!(mifp->m6_flags & MIFF_REGISTER)) {
692 		/*
693 		 * XXX: what if there is yet IPv4 multicast daemon
694 		 *      using the interface?
695 		 */
696 		ifp = mifp->m6_ifp;
697 
698 		if_allmulti(ifp, 0);
699 	} else {
700 		if (reg_mif_num != (mifi_t)-1 &&
701 		    multicast_register_if6 != NULL) {
702 			if_detach(multicast_register_if6);
703 			if_free(multicast_register_if6);
704 			reg_mif_num = (mifi_t)-1;
705 			multicast_register_if6 = NULL;
706 		}
707 	}
708 
709 	bzero((caddr_t)mifp, sizeof(*mifp));
710 
711 	/* Adjust nummifs down */
712 	for (mifi = nummifs; mifi > 0; mifi--)
713 		if (mif6table[mifi - 1].m6_ifp)
714 			break;
715 	nummifs = mifi;
716 
717 	splx(s);
718 
719 #ifdef MRT6DEBUG
720 	if (mrt6debug)
721 		log(LOG_DEBUG, "del_m6if %d, nummifs %d\n", *mifip, nummifs);
722 #endif
723 
724 	return (0);
725 }
726 
727 /*
728  * Add an mfc entry
729  */
730 static int
731 add_m6fc(struct mf6cctl *mfccp)
732 {
733 	struct mf6c *rt;
734 	u_long hash;
735 	struct rtdetq *rte;
736 	u_short nstl;
737 	int s;
738 	char ip6bufo[INET6_ADDRSTRLEN], ip6bufg[INET6_ADDRSTRLEN];
739 
740 	MF6CFIND(mfccp->mf6cc_origin.sin6_addr,
741 		 mfccp->mf6cc_mcastgrp.sin6_addr, rt);
742 
743 	/* If an entry already exists, just update the fields */
744 	if (rt) {
745 #ifdef MRT6DEBUG
746 		if (mrt6debug & DEBUG_MFC) {
747 		    log(LOG_DEBUG,
748 			"add_m6fc no upcall h %d o %s g %s p %x\n",
749 			ip6_sprintf(ip6bufo, &mfccp->mf6cc_origin.sin6_addr),
750 			ip6_sprintf(ip6bufg, &mfccp->mf6cc_mcastgrp.sin6_addr),
751 			mfccp->mf6cc_parent);
752 		}
753 #endif
754 
755 		s = splnet();
756 		rt->mf6c_parent = mfccp->mf6cc_parent;
757 		rt->mf6c_ifset = mfccp->mf6cc_ifset;
758 		splx(s);
759 		return (0);
760 	}
761 
762 	/*
763 	 * Find the entry for which the upcall was made and update
764 	 */
765 	s = splnet();
766 	hash = MF6CHASH(mfccp->mf6cc_origin.sin6_addr,
767 			mfccp->mf6cc_mcastgrp.sin6_addr);
768 	for (rt = mf6ctable[hash], nstl = 0; rt; rt = rt->mf6c_next) {
769 		if (IN6_ARE_ADDR_EQUAL(&rt->mf6c_origin.sin6_addr,
770 				       &mfccp->mf6cc_origin.sin6_addr) &&
771 		    IN6_ARE_ADDR_EQUAL(&rt->mf6c_mcastgrp.sin6_addr,
772 				       &mfccp->mf6cc_mcastgrp.sin6_addr) &&
773 		    (rt->mf6c_stall != NULL)) {
774 
775 			if (nstl++)
776 				log(LOG_ERR,
777 				    "add_m6fc: %s o %s g %s p %x dbx %p\n",
778 				    "multiple kernel entries",
779 				    ip6_sprintf(ip6bufo,
780 					    &mfccp->mf6cc_origin.sin6_addr),
781 				    ip6_sprintf(ip6bufg,
782 					    &mfccp->mf6cc_mcastgrp.sin6_addr),
783 				    mfccp->mf6cc_parent, rt->mf6c_stall);
784 
785 #ifdef MRT6DEBUG
786 			if (mrt6debug & DEBUG_MFC)
787 				log(LOG_DEBUG,
788 				    "add_m6fc o %s g %s p %x dbg %x\n",
789 				    ip6_sprintf(ip6bufo,
790 					    &mfccp->mf6cc_origin.sin6_addr),
791 				    ip6_sprintf(ip6bufg,
792 					    &mfccp->mf6cc_mcastgrp.sin6_addr),
793 				    mfccp->mf6cc_parent, rt->mf6c_stall);
794 #endif
795 
796 			rt->mf6c_origin     = mfccp->mf6cc_origin;
797 			rt->mf6c_mcastgrp   = mfccp->mf6cc_mcastgrp;
798 			rt->mf6c_parent     = mfccp->mf6cc_parent;
799 			rt->mf6c_ifset	    = mfccp->mf6cc_ifset;
800 			/* initialize pkt counters per src-grp */
801 			rt->mf6c_pkt_cnt    = 0;
802 			rt->mf6c_byte_cnt   = 0;
803 			rt->mf6c_wrong_if   = 0;
804 
805 			rt->mf6c_expire = 0;	/* Don't clean this guy up */
806 			n6expire[hash]--;
807 
808 			/* free packets Qed at the end of this entry */
809 			for (rte = rt->mf6c_stall; rte != NULL; ) {
810 				struct rtdetq *n = rte->next;
811 				ip6_mdq(rte->m, rte->ifp, rt);
812 				m_freem(rte->m);
813 #ifdef UPCALL_TIMING
814 				collate(&(rte->t));
815 #endif /* UPCALL_TIMING */
816 				free(rte, M_MRTABLE6);
817 				rte = n;
818 			}
819 			rt->mf6c_stall = NULL;
820 		}
821 	}
822 
823 	/*
824 	 * It is possible that an entry is being inserted without an upcall
825 	 */
826 	if (nstl == 0) {
827 #ifdef MRT6DEBUG
828 		if (mrt6debug & DEBUG_MFC)
829 		    log(LOG_DEBUG,
830 			"add_mfc no upcall h %d o %s g %s p %x\n",
831 			hash,
832 			ip6_sprintf(ip6bufo, &mfccp->mf6cc_origin.sin6_addr),
833 			ip6_sprintf(ip6bufg, &mfccp->mf6cc_mcastgrp.sin6_addr),
834 			mfccp->mf6cc_parent);
835 #endif
836 
837 		for (rt = mf6ctable[hash]; rt; rt = rt->mf6c_next) {
838 
839 			if (IN6_ARE_ADDR_EQUAL(&rt->mf6c_origin.sin6_addr,
840 					       &mfccp->mf6cc_origin.sin6_addr)&&
841 			    IN6_ARE_ADDR_EQUAL(&rt->mf6c_mcastgrp.sin6_addr,
842 					       &mfccp->mf6cc_mcastgrp.sin6_addr)) {
843 
844 				rt->mf6c_origin     = mfccp->mf6cc_origin;
845 				rt->mf6c_mcastgrp   = mfccp->mf6cc_mcastgrp;
846 				rt->mf6c_parent     = mfccp->mf6cc_parent;
847 				rt->mf6c_ifset	    = mfccp->mf6cc_ifset;
848 				/* initialize pkt counters per src-grp */
849 				rt->mf6c_pkt_cnt    = 0;
850 				rt->mf6c_byte_cnt   = 0;
851 				rt->mf6c_wrong_if   = 0;
852 
853 				if (rt->mf6c_expire)
854 					n6expire[hash]--;
855 				rt->mf6c_expire	   = 0;
856 			}
857 		}
858 		if (rt == NULL) {
859 			/* no upcall, so make a new entry */
860 			rt = (struct mf6c *)malloc(sizeof(*rt), M_MRTABLE6,
861 						  M_NOWAIT);
862 			if (rt == NULL) {
863 				splx(s);
864 				return (ENOBUFS);
865 			}
866 
867 			/* insert new entry at head of hash chain */
868 			rt->mf6c_origin     = mfccp->mf6cc_origin;
869 			rt->mf6c_mcastgrp   = mfccp->mf6cc_mcastgrp;
870 			rt->mf6c_parent     = mfccp->mf6cc_parent;
871 			rt->mf6c_ifset	    = mfccp->mf6cc_ifset;
872 			/* initialize pkt counters per src-grp */
873 			rt->mf6c_pkt_cnt    = 0;
874 			rt->mf6c_byte_cnt   = 0;
875 			rt->mf6c_wrong_if   = 0;
876 			rt->mf6c_expire     = 0;
877 			rt->mf6c_stall = NULL;
878 
879 			/* link into table */
880 			rt->mf6c_next  = mf6ctable[hash];
881 			mf6ctable[hash] = rt;
882 		}
883 	}
884 	splx(s);
885 	return (0);
886 }
887 
888 #ifdef UPCALL_TIMING
889 /*
890  * collect delay statistics on the upcalls
891  */
892 static void
893 collate(struct timeval *t)
894 {
895 	u_long d;
896 	struct timeval tp;
897 	u_long delta;
898 
899 	GET_TIME(tp);
900 
901 	if (TV_LT(*t, tp))
902 	{
903 		TV_DELTA(tp, *t, delta);
904 
905 		d = delta >> 10;
906 		if (d > UPCALL_MAX)
907 			d = UPCALL_MAX;
908 
909 		++upcall_data[d];
910 	}
911 }
912 #endif /* UPCALL_TIMING */
913 
914 /*
915  * Delete an mfc entry
916  */
917 static int
918 del_m6fc(struct mf6cctl *mfccp)
919 {
920 	struct sockaddr_in6	origin;
921 	struct sockaddr_in6	mcastgrp;
922 	struct mf6c		*rt;
923 	struct mf6c		**nptr;
924 	u_long		hash;
925 	int s;
926 
927 	origin = mfccp->mf6cc_origin;
928 	mcastgrp = mfccp->mf6cc_mcastgrp;
929 	hash = MF6CHASH(origin.sin6_addr, mcastgrp.sin6_addr);
930 
931 #ifdef MRT6DEBUG
932 	if (mrt6debug & DEBUG_MFC) {
933 		char ip6bufo[INET6_ADDRSTRLEN], ip6bufg[INET6_ADDRSTRLEN];
934 		log(LOG_DEBUG,"del_m6fc orig %s mcastgrp %s\n",
935 		    ip6_sprintf(ip6bufo, &origin.sin6_addr),
936 		    ip6_sprintf(ip6bufg, &mcastgrp.sin6_addr));
937 	}
938 #endif
939 
940 	s = splnet();
941 
942 	nptr = &mf6ctable[hash];
943 	while ((rt = *nptr) != NULL) {
944 		if (IN6_ARE_ADDR_EQUAL(&origin.sin6_addr,
945 				       &rt->mf6c_origin.sin6_addr) &&
946 		    IN6_ARE_ADDR_EQUAL(&mcastgrp.sin6_addr,
947 				       &rt->mf6c_mcastgrp.sin6_addr) &&
948 		    rt->mf6c_stall == NULL)
949 			break;
950 
951 		nptr = &rt->mf6c_next;
952 	}
953 	if (rt == NULL) {
954 		splx(s);
955 		return (EADDRNOTAVAIL);
956 	}
957 
958 	*nptr = rt->mf6c_next;
959 	free(rt, M_MRTABLE6);
960 
961 	splx(s);
962 
963 	return (0);
964 }
965 
966 static int
967 socket_send(struct socket *s, struct mbuf *mm, struct sockaddr_in6 *src)
968 {
969 
970 	if (s) {
971 		if (sbappendaddr(&s->so_rcv,
972 				 (struct sockaddr *)src,
973 				 mm, (struct mbuf *)0) != 0) {
974 			sorwakeup(s);
975 			return (0);
976 		}
977 	}
978 	m_freem(mm);
979 	return (-1);
980 }
981 
982 /*
983  * IPv6 multicast forwarding function. This function assumes that the packet
984  * pointed to by "ip6" has arrived on (or is about to be sent to) the interface
985  * pointed to by "ifp", and the packet is to be relayed to other networks
986  * that have members of the packet's destination IPv6 multicast group.
987  *
988  * The packet is returned unscathed to the caller, unless it is
989  * erroneous, in which case a non-zero return value tells the caller to
990  * discard it.
991  *
992  * NOTE: this implementation assumes that m->m_pkthdr.rcvif is NULL iff
993  * this function is called in the originating context (i.e., not when
994  * forwarding a packet from other node).  ip6_output(), which is currently the
995  * only function that calls this function is called in the originating context,
996  * explicitly ensures this condition.  It is caller's responsibility to ensure
997  * that if this function is called from somewhere else in the originating
998  * context in the future.
999  */
1000 int
1001 X_ip6_mforward(struct ip6_hdr *ip6, struct ifnet *ifp, struct mbuf *m)
1002 {
1003 	struct mf6c *rt;
1004 	struct mif6 *mifp;
1005 	struct mbuf *mm;
1006 	int s;
1007 	mifi_t mifi;
1008 	char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
1009 
1010 #ifdef MRT6DEBUG
1011 	if (mrt6debug & DEBUG_FORWARD)
1012 		log(LOG_DEBUG, "ip6_mforward: src %s, dst %s, ifindex %d\n",
1013 		    ip6_sprintf(ip6bufs, &ip6->ip6_src),
1014 		    ip6_sprintf(ip6bufd, &ip6->ip6_dst),
1015 		    ifp->if_index);
1016 #endif
1017 
1018 	/*
1019 	 * Don't forward a packet with Hop limit of zero or one,
1020 	 * or a packet destined to a local-only group.
1021 	 */
1022 	if (ip6->ip6_hlim <= 1 || IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst) ||
1023 	    IN6_IS_ADDR_MC_LINKLOCAL(&ip6->ip6_dst))
1024 		return (0);
1025 	ip6->ip6_hlim--;
1026 
1027 	/*
1028 	 * Source address check: do not forward packets with unspecified
1029 	 * source. It was discussed in July 2000, on ipngwg mailing list.
1030 	 * This is rather more serious than unicast cases, because some
1031 	 * MLD packets can be sent with the unspecified source address
1032 	 * (although such packets must normally set 1 to the hop limit field).
1033 	 */
1034 	if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src)) {
1035 		ip6stat.ip6s_cantforward++;
1036 		if (ip6_log_time + ip6_log_interval < time_second) {
1037 			ip6_log_time = time_second;
1038 			log(LOG_DEBUG,
1039 			    "cannot forward "
1040 			    "from %s to %s nxt %d received on %s\n",
1041 			    ip6_sprintf(ip6bufs, &ip6->ip6_src),
1042 			    ip6_sprintf(ip6bufd, &ip6->ip6_dst),
1043 			    ip6->ip6_nxt,
1044 			    if_name(m->m_pkthdr.rcvif));
1045 		}
1046 		return (0);
1047 	}
1048 
1049 	/*
1050 	 * Determine forwarding mifs from the forwarding cache table
1051 	 */
1052 	s = splnet();
1053 	MF6CFIND(ip6->ip6_src, ip6->ip6_dst, rt);
1054 
1055 	/* Entry exists, so forward if necessary */
1056 	if (rt) {
1057 		splx(s);
1058 		return (ip6_mdq(m, ifp, rt));
1059 	} else {
1060 		/*
1061 		 * If we don't have a route for packet's origin,
1062 		 * Make a copy of the packet &
1063 		 * send message to routing daemon
1064 		 */
1065 
1066 		struct mbuf *mb0;
1067 		struct rtdetq *rte;
1068 		u_long hash;
1069 /*		int i, npkts;*/
1070 #ifdef UPCALL_TIMING
1071 		struct timeval tp;
1072 
1073 		GET_TIME(tp);
1074 #endif /* UPCALL_TIMING */
1075 
1076 		mrt6stat.mrt6s_no_route++;
1077 #ifdef MRT6DEBUG
1078 		if (mrt6debug & (DEBUG_FORWARD | DEBUG_MFC))
1079 			log(LOG_DEBUG, "ip6_mforward: no rte s %s g %s\n",
1080 			    ip6_sprintf(ip6bufs, &ip6->ip6_src),
1081 			    ip6_sprintf(ip6bufd, &ip6->ip6_dst));
1082 #endif
1083 
1084 		/*
1085 		 * Allocate mbufs early so that we don't do extra work if we
1086 		 * are just going to fail anyway.
1087 		 */
1088 		rte = (struct rtdetq *)malloc(sizeof(*rte), M_MRTABLE6,
1089 					      M_NOWAIT);
1090 		if (rte == NULL) {
1091 			splx(s);
1092 			return (ENOBUFS);
1093 		}
1094 		mb0 = m_copy(m, 0, M_COPYALL);
1095 		/*
1096 		 * Pullup packet header if needed before storing it,
1097 		 * as other references may modify it in the meantime.
1098 		 */
1099 		if (mb0 &&
1100 		    (M_HASCL(mb0) || mb0->m_len < sizeof(struct ip6_hdr)))
1101 			mb0 = m_pullup(mb0, sizeof(struct ip6_hdr));
1102 		if (mb0 == NULL) {
1103 			free(rte, M_MRTABLE6);
1104 			splx(s);
1105 			return (ENOBUFS);
1106 		}
1107 
1108 		/* is there an upcall waiting for this packet? */
1109 		hash = MF6CHASH(ip6->ip6_src, ip6->ip6_dst);
1110 		for (rt = mf6ctable[hash]; rt; rt = rt->mf6c_next) {
1111 			if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_src,
1112 					       &rt->mf6c_origin.sin6_addr) &&
1113 			    IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst,
1114 					       &rt->mf6c_mcastgrp.sin6_addr) &&
1115 			    (rt->mf6c_stall != NULL))
1116 				break;
1117 		}
1118 
1119 		if (rt == NULL) {
1120 			struct mrt6msg *im;
1121 #ifdef MRT6_OINIT
1122 			struct omrt6msg *oim;
1123 #endif
1124 
1125 			/* no upcall, so make a new entry */
1126 			rt = (struct mf6c *)malloc(sizeof(*rt), M_MRTABLE6,
1127 						  M_NOWAIT);
1128 			if (rt == NULL) {
1129 				free(rte, M_MRTABLE6);
1130 				m_freem(mb0);
1131 				splx(s);
1132 				return (ENOBUFS);
1133 			}
1134 			/*
1135 			 * Make a copy of the header to send to the user
1136 			 * level process
1137 			 */
1138 			mm = m_copy(mb0, 0, sizeof(struct ip6_hdr));
1139 
1140 			if (mm == NULL) {
1141 				free(rte, M_MRTABLE6);
1142 				m_freem(mb0);
1143 				free(rt, M_MRTABLE6);
1144 				splx(s);
1145 				return (ENOBUFS);
1146 			}
1147 
1148 			/*
1149 			 * Send message to routing daemon
1150 			 */
1151 			sin6.sin6_addr = ip6->ip6_src;
1152 
1153 			im = NULL;
1154 #ifdef MRT6_OINIT
1155 			oim = NULL;
1156 #endif
1157 			switch (ip6_mrouter_ver) {
1158 #ifdef MRT6_OINIT
1159 			case MRT6_OINIT:
1160 				oim = mtod(mm, struct omrt6msg *);
1161 				oim->im6_msgtype = MRT6MSG_NOCACHE;
1162 				oim->im6_mbz = 0;
1163 				break;
1164 #endif
1165 			case MRT6_INIT:
1166 				im = mtod(mm, struct mrt6msg *);
1167 				im->im6_msgtype = MRT6MSG_NOCACHE;
1168 				im->im6_mbz = 0;
1169 				break;
1170 			default:
1171 				free(rte, M_MRTABLE6);
1172 				m_freem(mb0);
1173 				free(rt, M_MRTABLE6);
1174 				splx(s);
1175 				return (EINVAL);
1176 			}
1177 
1178 #ifdef MRT6DEBUG
1179 			if (mrt6debug & DEBUG_FORWARD)
1180 				log(LOG_DEBUG,
1181 				    "getting the iif info in the kernel\n");
1182 #endif
1183 
1184 			for (mifp = mif6table, mifi = 0;
1185 			     mifi < nummifs && mifp->m6_ifp != ifp;
1186 			     mifp++, mifi++)
1187 				;
1188 
1189 			switch (ip6_mrouter_ver) {
1190 #ifdef MRT6_OINIT
1191 			case MRT6_OINIT:
1192 				oim->im6_mif = mifi;
1193 				break;
1194 #endif
1195 			case MRT6_INIT:
1196 				im->im6_mif = mifi;
1197 				break;
1198 			}
1199 
1200 			if (socket_send(ip6_mrouter, mm, &sin6) < 0) {
1201 				log(LOG_WARNING, "ip6_mforward: ip6_mrouter "
1202 				    "socket queue full\n");
1203 				mrt6stat.mrt6s_upq_sockfull++;
1204 				free(rte, M_MRTABLE6);
1205 				m_freem(mb0);
1206 				free(rt, M_MRTABLE6);
1207 				splx(s);
1208 				return (ENOBUFS);
1209 			}
1210 
1211 			mrt6stat.mrt6s_upcalls++;
1212 
1213 			/* insert new entry at head of hash chain */
1214 			bzero(rt, sizeof(*rt));
1215 			rt->mf6c_origin.sin6_family = AF_INET6;
1216 			rt->mf6c_origin.sin6_len = sizeof(struct sockaddr_in6);
1217 			rt->mf6c_origin.sin6_addr = ip6->ip6_src;
1218 			rt->mf6c_mcastgrp.sin6_family = AF_INET6;
1219 			rt->mf6c_mcastgrp.sin6_len = sizeof(struct sockaddr_in6);
1220 			rt->mf6c_mcastgrp.sin6_addr = ip6->ip6_dst;
1221 			rt->mf6c_expire = UPCALL_EXPIRE;
1222 			n6expire[hash]++;
1223 			rt->mf6c_parent = MF6C_INCOMPLETE_PARENT;
1224 
1225 			/* link into table */
1226 			rt->mf6c_next  = mf6ctable[hash];
1227 			mf6ctable[hash] = rt;
1228 			/* Add this entry to the end of the queue */
1229 			rt->mf6c_stall = rte;
1230 		} else {
1231 			/* determine if q has overflowed */
1232 			struct rtdetq **p;
1233 			int npkts = 0;
1234 
1235 			for (p = &rt->mf6c_stall; *p != NULL; p = &(*p)->next)
1236 				if (++npkts > MAX_UPQ6) {
1237 					mrt6stat.mrt6s_upq_ovflw++;
1238 					free(rte, M_MRTABLE6);
1239 					m_freem(mb0);
1240 					splx(s);
1241 					return (0);
1242 				}
1243 
1244 			/* Add this entry to the end of the queue */
1245 			*p = rte;
1246 		}
1247 
1248 		rte->next = NULL;
1249 		rte->m = mb0;
1250 		rte->ifp = ifp;
1251 #ifdef UPCALL_TIMING
1252 		rte->t = tp;
1253 #endif /* UPCALL_TIMING */
1254 
1255 		splx(s);
1256 
1257 		return (0);
1258 	}
1259 }
1260 
1261 /*
1262  * Clean up cache entries if upcalls are not serviced
1263  * Call from the Slow Timeout mechanism, every half second.
1264  */
1265 static void
1266 expire_upcalls(void *unused)
1267 {
1268 	struct rtdetq *rte;
1269 	struct mf6c *mfc, **nptr;
1270 	int i;
1271 	int s;
1272 
1273 	s = splnet();
1274 	for (i = 0; i < MF6CTBLSIZ; i++) {
1275 		if (n6expire[i] == 0)
1276 			continue;
1277 		nptr = &mf6ctable[i];
1278 		while ((mfc = *nptr) != NULL) {
1279 			rte = mfc->mf6c_stall;
1280 			/*
1281 			 * Skip real cache entries
1282 			 * Make sure it wasn't marked to not expire (shouldn't happen)
1283 			 * If it expires now
1284 			 */
1285 			if (rte != NULL &&
1286 			    mfc->mf6c_expire != 0 &&
1287 			    --mfc->mf6c_expire == 0) {
1288 #ifdef MRT6DEBUG
1289 				if (mrt6debug & DEBUG_EXPIRE) {
1290 					char ip6bufo[INET6_ADDRSTRLEN];
1291 					char ip6bufg[INET6_ADDRSTRLEN];
1292 					log(LOG_DEBUG, "expire_upcalls: expiring (%s %s)\n",
1293 					    ip6_sprintf(ip6bufo, &mfc->mf6c_origin.sin6_addr),
1294 					    ip6_sprintf(ip6bufg, &mfc->mf6c_mcastgrp.sin6_addr));
1295 				}
1296 #endif
1297 				/*
1298 				 * drop all the packets
1299 				 * free the mbuf with the pkt, if, timing info
1300 				 */
1301 				do {
1302 					struct rtdetq *n = rte->next;
1303 					m_freem(rte->m);
1304 					free(rte, M_MRTABLE6);
1305 					rte = n;
1306 				} while (rte != NULL);
1307 				mrt6stat.mrt6s_cache_cleanups++;
1308 				n6expire[i]--;
1309 
1310 				*nptr = mfc->mf6c_next;
1311 				free(mfc, M_MRTABLE6);
1312 			} else {
1313 				nptr = &mfc->mf6c_next;
1314 			}
1315 		}
1316 	}
1317 	splx(s);
1318 	callout_reset(&expire_upcalls_ch, EXPIRE_TIMEOUT,
1319 	    expire_upcalls, NULL);
1320 }
1321 
1322 /*
1323  * Packet forwarding routine once entry in the cache is made
1324  */
1325 static int
1326 ip6_mdq(struct mbuf *m, struct ifnet *ifp, struct mf6c *rt)
1327 {
1328 	struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1329 	mifi_t mifi, iif;
1330 	struct mif6 *mifp;
1331 	int plen = m->m_pkthdr.len;
1332 	struct in6_addr src0, dst0; /* copies for local work */
1333 	u_int32_t iszone, idzone, oszone, odzone;
1334 	int error = 0;
1335 
1336 /*
1337  * Macro to send packet on mif.  Since RSVP packets don't get counted on
1338  * input, they shouldn't get counted on output, so statistics keeping is
1339  * separate.
1340  */
1341 
1342 #define MC6_SEND(ip6, mifp, m) do {				\
1343 	if ((mifp)->m6_flags & MIFF_REGISTER)			\
1344 		register_send((ip6), (mifp), (m));		\
1345 	else							\
1346 		phyint_send((ip6), (mifp), (m));		\
1347 } while (/*CONSTCOND*/ 0)
1348 
1349 	/*
1350 	 * Don't forward if it didn't arrive from the parent mif
1351 	 * for its origin.
1352 	 */
1353 	mifi = rt->mf6c_parent;
1354 	if ((mifi >= nummifs) || (mif6table[mifi].m6_ifp != ifp)) {
1355 		/* came in the wrong interface */
1356 #ifdef MRT6DEBUG
1357 		if (mrt6debug & DEBUG_FORWARD)
1358 			log(LOG_DEBUG,
1359 			    "wrong if: ifid %d mifi %d mififid %x\n",
1360 			    ifp->if_index, mifi,
1361 			    mif6table[mifi].m6_ifp->if_index);
1362 #endif
1363 		mrt6stat.mrt6s_wrong_if++;
1364 		rt->mf6c_wrong_if++;
1365 		/*
1366 		 * If we are doing PIM processing, and we are forwarding
1367 		 * packets on this interface, send a message to the
1368 		 * routing daemon.
1369 		 */
1370 		/* have to make sure this is a valid mif */
1371 		if (mifi < nummifs && mif6table[mifi].m6_ifp)
1372 			if (pim6 && (m->m_flags & M_LOOP) == 0) {
1373 				/*
1374 				 * Check the M_LOOP flag to avoid an
1375 				 * unnecessary PIM assert.
1376 				 * XXX: M_LOOP is an ad-hoc hack...
1377 				 */
1378 				static struct sockaddr_in6 sin6 =
1379 				{ sizeof(sin6), AF_INET6 };
1380 
1381 				struct mbuf *mm;
1382 				struct mrt6msg *im;
1383 #ifdef MRT6_OINIT
1384 				struct omrt6msg *oim;
1385 #endif
1386 
1387 				mm = m_copy(m, 0, sizeof(struct ip6_hdr));
1388 				if (mm &&
1389 				    (M_HASCL(mm) ||
1390 				     mm->m_len < sizeof(struct ip6_hdr)))
1391 					mm = m_pullup(mm, sizeof(struct ip6_hdr));
1392 				if (mm == NULL)
1393 					return (ENOBUFS);
1394 
1395 #ifdef MRT6_OINIT
1396 				oim = NULL;
1397 #endif
1398 				im = NULL;
1399 				switch (ip6_mrouter_ver) {
1400 #ifdef MRT6_OINIT
1401 				case MRT6_OINIT:
1402 					oim = mtod(mm, struct omrt6msg *);
1403 					oim->im6_msgtype = MRT6MSG_WRONGMIF;
1404 					oim->im6_mbz = 0;
1405 					break;
1406 #endif
1407 				case MRT6_INIT:
1408 					im = mtod(mm, struct mrt6msg *);
1409 					im->im6_msgtype = MRT6MSG_WRONGMIF;
1410 					im->im6_mbz = 0;
1411 					break;
1412 				default:
1413 					m_freem(mm);
1414 					return (EINVAL);
1415 				}
1416 
1417 				for (mifp = mif6table, iif = 0;
1418 				     iif < nummifs && mifp &&
1419 					     mifp->m6_ifp != ifp;
1420 				     mifp++, iif++)
1421 					;
1422 
1423 				switch (ip6_mrouter_ver) {
1424 #ifdef MRT6_OINIT
1425 				case MRT6_OINIT:
1426 					oim->im6_mif = iif;
1427 					sin6.sin6_addr = oim->im6_src;
1428 					break;
1429 #endif
1430 				case MRT6_INIT:
1431 					im->im6_mif = iif;
1432 					sin6.sin6_addr = im->im6_src;
1433 					break;
1434 				}
1435 
1436 				mrt6stat.mrt6s_upcalls++;
1437 
1438 				if (socket_send(ip6_mrouter, mm, &sin6) < 0) {
1439 #ifdef MRT6DEBUG
1440 					if (mrt6debug)
1441 						log(LOG_WARNING, "mdq, ip6_mrouter socket queue full\n");
1442 #endif
1443 					++mrt6stat.mrt6s_upq_sockfull;
1444 					return (ENOBUFS);
1445 				}	/* if socket Q full */
1446 			}		/* if PIM */
1447 		return (0);
1448 	}			/* if wrong iif */
1449 
1450 	/* If I sourced this packet, it counts as output, else it was input. */
1451 	if (m->m_pkthdr.rcvif == NULL) {
1452 		/* XXX: is rcvif really NULL when output?? */
1453 		mif6table[mifi].m6_pkt_out++;
1454 		mif6table[mifi].m6_bytes_out += plen;
1455 	} else {
1456 		mif6table[mifi].m6_pkt_in++;
1457 		mif6table[mifi].m6_bytes_in += plen;
1458 	}
1459 	rt->mf6c_pkt_cnt++;
1460 	rt->mf6c_byte_cnt += plen;
1461 
1462 	/*
1463 	 * For each mif, forward a copy of the packet if there are group
1464 	 * members downstream on the interface.
1465 	 */
1466 	src0 = ip6->ip6_src;
1467 	dst0 = ip6->ip6_dst;
1468 	if ((error = in6_setscope(&src0, ifp, &iszone)) != 0 ||
1469 	    (error = in6_setscope(&dst0, ifp, &idzone)) != 0) {
1470 		ip6stat.ip6s_badscope++;
1471 		return (error);
1472 	}
1473 	for (mifp = mif6table, mifi = 0; mifi < nummifs; mifp++, mifi++) {
1474 		if (IF_ISSET(mifi, &rt->mf6c_ifset)) {
1475 			/*
1476 			 * check if the outgoing packet is going to break
1477 			 * a scope boundary.
1478 			 * XXX For packets through PIM register tunnel
1479 			 * interface, we believe a routing daemon.
1480 			 */
1481 			if (!(mif6table[rt->mf6c_parent].m6_flags &
1482 			      MIFF_REGISTER) &&
1483 			    !(mif6table[mifi].m6_flags & MIFF_REGISTER)) {
1484 				if (in6_setscope(&src0, mif6table[mifi].m6_ifp,
1485 				    &oszone) ||
1486 				    in6_setscope(&dst0, mif6table[mifi].m6_ifp,
1487 				    &odzone) ||
1488 				    iszone != oszone ||
1489 				    idzone != odzone) {
1490 					ip6stat.ip6s_badscope++;
1491 					continue;
1492 				}
1493 			}
1494 
1495 			mifp->m6_pkt_out++;
1496 			mifp->m6_bytes_out += plen;
1497 			MC6_SEND(ip6, mifp, m);
1498 		}
1499 	}
1500 	return (0);
1501 }
1502 
1503 static void
1504 phyint_send(struct ip6_hdr *ip6, struct mif6 *mifp, struct mbuf *m)
1505 {
1506 	struct mbuf *mb_copy;
1507 	struct ifnet *ifp = mifp->m6_ifp;
1508 	int error = 0;
1509 	int s = splnet();	/* needs to protect static "ro" below. */
1510 	static struct route_in6 ro;
1511 	struct	in6_multi *in6m;
1512 	struct sockaddr_in6 *dst6;
1513 	u_long linkmtu;
1514 
1515 	/*
1516 	 * Make a new reference to the packet; make sure that
1517 	 * the IPv6 header is actually copied, not just referenced,
1518 	 * so that ip6_output() only scribbles on the copy.
1519 	 */
1520 	mb_copy = m_copy(m, 0, M_COPYALL);
1521 	if (mb_copy &&
1522 	    (M_HASCL(mb_copy) || mb_copy->m_len < sizeof(struct ip6_hdr)))
1523 		mb_copy = m_pullup(mb_copy, sizeof(struct ip6_hdr));
1524 	if (mb_copy == NULL) {
1525 		splx(s);
1526 		return;
1527 	}
1528 	/* set MCAST flag to the outgoing packet */
1529 	mb_copy->m_flags |= M_MCAST;
1530 
1531 	/*
1532 	 * If we sourced the packet, call ip6_output since we may devide
1533 	 * the packet into fragments when the packet is too big for the
1534 	 * outgoing interface.
1535 	 * Otherwise, we can simply send the packet to the interface
1536 	 * sending queue.
1537 	 */
1538 	if (m->m_pkthdr.rcvif == NULL) {
1539 		struct ip6_moptions im6o;
1540 
1541 		im6o.im6o_multicast_ifp = ifp;
1542 		/* XXX: ip6_output will override ip6->ip6_hlim */
1543 		im6o.im6o_multicast_hlim = ip6->ip6_hlim;
1544 		im6o.im6o_multicast_loop = 1;
1545 		error = ip6_output(mb_copy, NULL, &ro,
1546 				   IPV6_FORWARDING, &im6o, NULL, NULL);
1547 
1548 #ifdef MRT6DEBUG
1549 		if (mrt6debug & DEBUG_XMIT)
1550 			log(LOG_DEBUG, "phyint_send on mif %d err %d\n",
1551 			    mifp - mif6table, error);
1552 #endif
1553 		splx(s);
1554 		return;
1555 	}
1556 
1557 	/*
1558 	 * If we belong to the destination multicast group
1559 	 * on the outgoing interface, loop back a copy.
1560 	 */
1561 	dst6 = (struct sockaddr_in6 *)&ro.ro_dst;
1562 	IN6_LOOKUP_MULTI(ip6->ip6_dst, ifp, in6m);
1563 	if (in6m != NULL) {
1564 		dst6->sin6_len = sizeof(struct sockaddr_in6);
1565 		dst6->sin6_family = AF_INET6;
1566 		dst6->sin6_addr = ip6->ip6_dst;
1567 		ip6_mloopback(ifp, m, (struct sockaddr_in6 *)&ro.ro_dst);
1568 	}
1569 	/*
1570 	 * Put the packet into the sending queue of the outgoing interface
1571 	 * if it would fit in the MTU of the interface.
1572 	 */
1573 	linkmtu = IN6_LINKMTU(ifp);
1574 	if (mb_copy->m_pkthdr.len <= linkmtu || linkmtu < IPV6_MMTU) {
1575 		dst6->sin6_len = sizeof(struct sockaddr_in6);
1576 		dst6->sin6_family = AF_INET6;
1577 		dst6->sin6_addr = ip6->ip6_dst;
1578 		/*
1579 		 * We just call if_output instead of nd6_output here, since
1580 		 * we need no ND for a multicast forwarded packet...right?
1581 		 */
1582 		error = (*ifp->if_output)(ifp, mb_copy,
1583 		    (struct sockaddr *)&ro.ro_dst, NULL);
1584 #ifdef MRT6DEBUG
1585 		if (mrt6debug & DEBUG_XMIT)
1586 			log(LOG_DEBUG, "phyint_send on mif %d err %d\n",
1587 			    mifp - mif6table, error);
1588 #endif
1589 	} else {
1590 		/*
1591 		 * pMTU discovery is intentionally disabled by default, since
1592 		 * various router may notify pMTU in multicast, which can be
1593 		 * a DDoS to a router
1594 		 */
1595 		if (ip6_mcast_pmtu)
1596 			icmp6_error(mb_copy, ICMP6_PACKET_TOO_BIG, 0, linkmtu);
1597 		else {
1598 #ifdef MRT6DEBUG
1599 			if (mrt6debug & DEBUG_XMIT) {
1600 				char ip6bufs[INET6_ADDRSTRLEN];
1601 				char ip6bufd[INET6_ADDRSTRLEN];
1602 				log(LOG_DEBUG,
1603 				    "phyint_send: packet too big on %s o %s "
1604 				    "g %s size %d(discarded)\n",
1605 				    if_name(ifp),
1606 				    ip6_sprintf(ip6bufs, &ip6->ip6_src),
1607 				    ip6_sprintf(ip6bufd, &ip6->ip6_dst),
1608 				    mb_copy->m_pkthdr.len);
1609 			}
1610 #endif /* MRT6DEBUG */
1611 			m_freem(mb_copy); /* simply discard the packet */
1612 		}
1613 	}
1614 
1615 	splx(s);
1616 }
1617 
1618 static int
1619 register_send(struct ip6_hdr *ip6, struct mif6 *mif, struct mbuf *m)
1620 {
1621 	struct mbuf *mm;
1622 	int i, len = m->m_pkthdr.len;
1623 	static struct sockaddr_in6 sin6 = { sizeof(sin6), AF_INET6 };
1624 	struct mrt6msg *im6;
1625 
1626 #ifdef MRT6DEBUG
1627 	if (mrt6debug) {
1628 		char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
1629 		log(LOG_DEBUG, "** IPv6 register_send **\n src %s dst %s\n",
1630 		    ip6_sprintf(ip6bufs, &ip6->ip6_src),
1631 		    ip6_sprintf(ip6bufd, &ip6->ip6_dst));
1632 	}
1633 #endif
1634 	++pim6stat.pim6s_snd_registers;
1635 
1636 	/* Make a copy of the packet to send to the user level process */
1637 	MGETHDR(mm, M_DONTWAIT, MT_HEADER);
1638 	if (mm == NULL)
1639 		return (ENOBUFS);
1640 	mm->m_pkthdr.rcvif = NULL;
1641 	mm->m_data += max_linkhdr;
1642 	mm->m_len = sizeof(struct ip6_hdr);
1643 
1644 	if ((mm->m_next = m_copy(m, 0, M_COPYALL)) == NULL) {
1645 		m_freem(mm);
1646 		return (ENOBUFS);
1647 	}
1648 	i = MHLEN - M_LEADINGSPACE(mm);
1649 	if (i > len)
1650 		i = len;
1651 	mm = m_pullup(mm, i);
1652 	if (mm == NULL)
1653 		return (ENOBUFS);
1654 /* TODO: check it! */
1655 	mm->m_pkthdr.len = len + sizeof(struct ip6_hdr);
1656 
1657 	/*
1658 	 * Send message to routing daemon
1659 	 */
1660 	sin6.sin6_addr = ip6->ip6_src;
1661 
1662 	im6 = mtod(mm, struct mrt6msg *);
1663 	im6->im6_msgtype      = MRT6MSG_WHOLEPKT;
1664 	im6->im6_mbz          = 0;
1665 
1666 	im6->im6_mif = mif - mif6table;
1667 
1668 	/* iif info is not given for reg. encap.n */
1669 	mrt6stat.mrt6s_upcalls++;
1670 
1671 	if (socket_send(ip6_mrouter, mm, &sin6) < 0) {
1672 #ifdef MRT6DEBUG
1673 		if (mrt6debug)
1674 			log(LOG_WARNING,
1675 			    "register_send: ip6_mrouter socket queue full\n");
1676 #endif
1677 		++mrt6stat.mrt6s_upq_sockfull;
1678 		return (ENOBUFS);
1679 	}
1680 	return (0);
1681 }
1682 
1683 /*
1684  * PIM sparse mode hook
1685  * Receives the pim control messages, and passes them up to the listening
1686  * socket, using rip6_input.
1687  * The only message processed is the REGISTER pim message; the pim header
1688  * is stripped off, and the inner packet is passed to register_mforward.
1689  */
1690 int
1691 pim6_input(struct mbuf **mp, int *offp, int proto)
1692 {
1693 	struct pim *pim; /* pointer to a pim struct */
1694 	struct ip6_hdr *ip6;
1695 	int pimlen;
1696 	struct mbuf *m = *mp;
1697 	int minlen;
1698 	int off = *offp;
1699 
1700 	++pim6stat.pim6s_rcv_total;
1701 
1702 	ip6 = mtod(m, struct ip6_hdr *);
1703 	pimlen = m->m_pkthdr.len - *offp;
1704 
1705 	/*
1706 	 * Validate lengths
1707 	 */
1708 	if (pimlen < PIM_MINLEN) {
1709 		++pim6stat.pim6s_rcv_tooshort;
1710 #ifdef MRT6DEBUG
1711 		if (mrt6debug & DEBUG_PIM)
1712 			log(LOG_DEBUG,"pim6_input: PIM packet too short\n");
1713 #endif
1714 		m_freem(m);
1715 		return (IPPROTO_DONE);
1716 	}
1717 
1718 	/*
1719 	 * if the packet is at least as big as a REGISTER, go ahead
1720 	 * and grab the PIM REGISTER header size, to avoid another
1721 	 * possible m_pullup() later.
1722 	 *
1723 	 * PIM_MINLEN       == pimhdr + u_int32 == 8
1724 	 * PIM6_REG_MINLEN   == pimhdr + reghdr + eip6hdr == 4 + 4 + 40
1725 	 */
1726 	minlen = (pimlen >= PIM6_REG_MINLEN) ? PIM6_REG_MINLEN : PIM_MINLEN;
1727 
1728 	/*
1729 	 * Make sure that the IP6 and PIM headers in contiguous memory, and
1730 	 * possibly the PIM REGISTER header
1731 	 */
1732 #ifndef PULLDOWN_TEST
1733 	IP6_EXTHDR_CHECK(m, off, minlen, IPPROTO_DONE);
1734 	/* adjust pointer */
1735 	ip6 = mtod(m, struct ip6_hdr *);
1736 
1737 	/* adjust mbuf to point to the PIM header */
1738 	pim = (struct pim *)((caddr_t)ip6 + off);
1739 #else
1740 	IP6_EXTHDR_GET(pim, struct pim *, m, off, minlen);
1741 	if (pim == NULL) {
1742 		pim6stat.pim6s_rcv_tooshort++;
1743 		return (IPPROTO_DONE);
1744 	}
1745 #endif
1746 
1747 #define PIM6_CHECKSUM
1748 #ifdef PIM6_CHECKSUM
1749 	{
1750 		int cksumlen;
1751 
1752 		/*
1753 		 * Validate checksum.
1754 		 * If PIM REGISTER, exclude the data packet
1755 		 */
1756 		if (pim->pim_type == PIM_REGISTER)
1757 			cksumlen = PIM_MINLEN;
1758 		else
1759 			cksumlen = pimlen;
1760 
1761 		if (in6_cksum(m, IPPROTO_PIM, off, cksumlen)) {
1762 			++pim6stat.pim6s_rcv_badsum;
1763 #ifdef MRT6DEBUG
1764 			if (mrt6debug & DEBUG_PIM)
1765 				log(LOG_DEBUG,
1766 				    "pim6_input: invalid checksum\n");
1767 #endif
1768 			m_freem(m);
1769 			return (IPPROTO_DONE);
1770 		}
1771 	}
1772 #endif /* PIM_CHECKSUM */
1773 
1774 	/* PIM version check */
1775 	if (pim->pim_ver != PIM_VERSION) {
1776 		++pim6stat.pim6s_rcv_badversion;
1777 #ifdef MRT6DEBUG
1778 		log(LOG_ERR,
1779 		    "pim6_input: incorrect version %d, expecting %d\n",
1780 		    pim->pim_ver, PIM_VERSION);
1781 #endif
1782 		m_freem(m);
1783 		return (IPPROTO_DONE);
1784 	}
1785 
1786 	if (pim->pim_type == PIM_REGISTER) {
1787 		/*
1788 		 * since this is a REGISTER, we'll make a copy of the register
1789 		 * headers ip6+pim+u_int32_t+encap_ip6, to be passed up to the
1790 		 * routing daemon.
1791 		 */
1792 		static struct sockaddr_in6 dst = { sizeof(dst), AF_INET6 };
1793 
1794 		struct mbuf *mcp;
1795 		struct ip6_hdr *eip6;
1796 		u_int32_t *reghdr;
1797 		int rc;
1798 #ifdef MRT6DEBUG
1799 		char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
1800 #endif
1801 
1802 		++pim6stat.pim6s_rcv_registers;
1803 
1804 		if ((reg_mif_num >= nummifs) || (reg_mif_num == (mifi_t) -1)) {
1805 #ifdef MRT6DEBUG
1806 			if (mrt6debug & DEBUG_PIM)
1807 				log(LOG_DEBUG,
1808 				    "pim6_input: register mif not set: %d\n",
1809 				    reg_mif_num);
1810 #endif
1811 			m_freem(m);
1812 			return (IPPROTO_DONE);
1813 		}
1814 
1815 		reghdr = (u_int32_t *)(pim + 1);
1816 
1817 		if ((ntohl(*reghdr) & PIM_NULL_REGISTER))
1818 			goto pim6_input_to_daemon;
1819 
1820 		/*
1821 		 * Validate length
1822 		 */
1823 		if (pimlen < PIM6_REG_MINLEN) {
1824 			++pim6stat.pim6s_rcv_tooshort;
1825 			++pim6stat.pim6s_rcv_badregisters;
1826 #ifdef MRT6DEBUG
1827 			log(LOG_ERR,
1828 			    "pim6_input: register packet size too "
1829 			    "small %d from %s\n",
1830 			    pimlen, ip6_sprintf(ip6bufs, &ip6->ip6_src));
1831 #endif
1832 			m_freem(m);
1833 			return (IPPROTO_DONE);
1834 		}
1835 
1836 		eip6 = (struct ip6_hdr *) (reghdr + 1);
1837 #ifdef MRT6DEBUG
1838 		if (mrt6debug & DEBUG_PIM)
1839 			log(LOG_DEBUG,
1840 			    "pim6_input[register], eip6: %s -> %s, "
1841 			    "eip6 plen %d\n",
1842 			    ip6_sprintf(ip6bufs, &eip6->ip6_src),
1843 			    ip6_sprintf(ip6bufd, &eip6->ip6_dst),
1844 			    ntohs(eip6->ip6_plen));
1845 #endif
1846 
1847 		/* verify the version number of the inner packet */
1848 		if ((eip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
1849 			++pim6stat.pim6s_rcv_badregisters;
1850 #ifdef MRT6DEBUG
1851 			log(LOG_DEBUG, "pim6_input: invalid IP version (%d) "
1852 			    "of the inner packet\n",
1853 			    (eip6->ip6_vfc & IPV6_VERSION));
1854 #endif
1855 			m_freem(m);
1856 			return (IPPROTO_NONE);
1857 		}
1858 
1859 		/* verify the inner packet is destined to a mcast group */
1860 		if (!IN6_IS_ADDR_MULTICAST(&eip6->ip6_dst)) {
1861 			++pim6stat.pim6s_rcv_badregisters;
1862 #ifdef MRT6DEBUG
1863 			if (mrt6debug & DEBUG_PIM)
1864 				log(LOG_DEBUG,
1865 				    "pim6_input: inner packet of register "
1866 				    "is not multicast %s\n",
1867 				    ip6_sprintf(ip6bufd, &eip6->ip6_dst));
1868 #endif
1869 			m_freem(m);
1870 			return (IPPROTO_DONE);
1871 		}
1872 
1873 		/*
1874 		 * make a copy of the whole header to pass to the daemon later.
1875 		 */
1876 		mcp = m_copy(m, 0, off + PIM6_REG_MINLEN);
1877 		if (mcp == NULL) {
1878 #ifdef MRT6DEBUG
1879 			log(LOG_ERR,
1880 			    "pim6_input: pim register: "
1881 			    "could not copy register head\n");
1882 #endif
1883 			m_freem(m);
1884 			return (IPPROTO_DONE);
1885 		}
1886 
1887 		/*
1888 		 * forward the inner ip6 packet; point m_data at the inner ip6.
1889 		 */
1890 		m_adj(m, off + PIM_MINLEN);
1891 #ifdef MRT6DEBUG
1892 		if (mrt6debug & DEBUG_PIM) {
1893 			log(LOG_DEBUG,
1894 			    "pim6_input: forwarding decapsulated register: "
1895 			    "src %s, dst %s, mif %d\n",
1896 			    ip6_sprintf(ip6bufs, &eip6->ip6_src),
1897 			    ip6_sprintf(ip6bufd, &eip6->ip6_dst),
1898 			    reg_mif_num);
1899 		}
1900 #endif
1901 
1902 		rc = if_simloop(mif6table[reg_mif_num].m6_ifp, m,
1903 				dst.sin6_family, 0);
1904 
1905 		/* prepare the register head to send to the mrouting daemon */
1906 		m = mcp;
1907 	}
1908 
1909 	/*
1910 	 * Pass the PIM message up to the daemon; if it is a register message
1911 	 * pass the 'head' only up to the daemon. This includes the
1912 	 * encapsulator ip6 header, pim header, register header and the
1913 	 * encapsulated ip6 header.
1914 	 */
1915   pim6_input_to_daemon:
1916 	rip6_input(&m, offp, proto);
1917 	return (IPPROTO_DONE);
1918 }
1919