xref: /freebsd/sys/netinet6/ip6_mroute.c (revision a9148abd9da5db2f1c682fb17bed791845fc41c9)
1 /*-
2  * Copyright (C) 1998 WIDE Project.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the project nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  *	$KAME: ip6_mroute.c,v 1.58 2001/12/18 02:36:31 itojun Exp $
30  */
31 
32 /*-
33  * Copyright (c) 1989 Stephen Deering
34  * Copyright (c) 1992, 1993
35  *      The Regents of the University of California.  All rights reserved.
36  *
37  * This code is derived from software contributed to Berkeley by
38  * Stephen Deering of Stanford University.
39  *
40  * Redistribution and use in source and binary forms, with or without
41  * modification, are permitted provided that the following conditions
42  * are met:
43  * 1. Redistributions of source code must retain the above copyright
44  *    notice, this list of conditions and the following disclaimer.
45  * 2. Redistributions in binary form must reproduce the above copyright
46  *    notice, this list of conditions and the following disclaimer in the
47  *    documentation and/or other materials provided with the distribution.
48  * 4. Neither the name of the University nor the names of its contributors
49  *    may be used to endorse or promote products derived from this software
50  *    without specific prior written permission.
51  *
52  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
53  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
54  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
55  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
56  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
57  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
58  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
59  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
60  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
61  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
62  * SUCH DAMAGE.
63  *
64  *	@(#)ip_mroute.c	8.2 (Berkeley) 11/15/93
65  *	BSDI ip_mroute.c,v 2.10 1996/11/14 00:29:52 jch Exp
66  */
67 
68 /*
69  * IP multicast forwarding procedures
70  *
71  * Written by David Waitzman, BBN Labs, August 1988.
72  * Modified by Steve Deering, Stanford, February 1989.
73  * Modified by Mark J. Steiglitz, Stanford, May, 1991
74  * Modified by Van Jacobson, LBL, January 1993
75  * Modified by Ajit Thyagarajan, PARC, August 1993
76  * Modified by Bill Fenner, PARC, April 1994
77  *
78  * MROUTING Revision: 3.5.1.2 + PIM-SMv2 (pimd) Support
79  */
80 
81 #include <sys/cdefs.h>
82 __FBSDID("$FreeBSD$");
83 
84 #include "opt_inet.h"
85 #include "opt_inet6.h"
86 
87 #include <sys/param.h>
88 #include <sys/callout.h>
89 #include <sys/errno.h>
90 #include <sys/kernel.h>
91 #include <sys/lock.h>
92 #include <sys/malloc.h>
93 #include <sys/mbuf.h>
94 #include <sys/protosw.h>
95 #include <sys/signalvar.h>
96 #include <sys/socket.h>
97 #include <sys/socketvar.h>
98 #include <sys/sockio.h>
99 #include <sys/sx.h>
100 #include <sys/sysctl.h>
101 #include <sys/syslog.h>
102 #include <sys/systm.h>
103 #include <sys/time.h>
104 #include <sys/vimage.h>
105 
106 #include <net/if.h>
107 #include <net/if_types.h>
108 #include <net/raw_cb.h>
109 #include <net/route.h>
110 
111 #include <netinet/in.h>
112 #include <netinet/in_var.h>
113 #include <netinet/icmp6.h>
114 
115 #include <netinet/ip6.h>
116 #include <netinet6/ip6_var.h>
117 #include <netinet6/scope6_var.h>
118 #include <netinet6/nd6.h>
119 #include <netinet6/ip6_mroute.h>
120 #include <netinet6/ip6protosw.h>
121 #include <netinet6/pim6.h>
122 #include <netinet6/pim6_var.h>
123 
124 static MALLOC_DEFINE(M_MRTABLE6, "mf6c", "multicast forwarding cache entry");
125 
126 /* XXX: this is a very common idiom; move to <sys/mbuf.h> ? */
127 #define M_HASCL(m) ((m)->m_flags & M_EXT)
128 
129 static int ip6_mdq(struct mbuf *, struct ifnet *, struct mf6c *);
130 static void phyint_send(struct ip6_hdr *, struct mif6 *, struct mbuf *);
131 
132 static int set_pim6(int *);
133 static int socket_send __P((struct socket *, struct mbuf *,
134 	    struct sockaddr_in6 *));
135 static int register_send __P((struct ip6_hdr *, struct mif6 *,
136 	    struct mbuf *));
137 
138 extern struct domain inet6domain;
139 
140 /* XXX: referenced from ip_mroute.c for dynamically loading this code. */
141 struct ip6protosw in6_pim_protosw = {
142 	.pr_type =		SOCK_RAW,
143 	.pr_domain =		&inet6domain,
144 	.pr_protocol =		IPPROTO_PIM,
145 	.pr_flags =		PR_ATOMIC|PR_ADDR|PR_LASTHDR,
146 	.pr_input =		pim6_input,
147 	.pr_output =		rip6_output,
148 	.pr_ctloutput =		rip6_ctloutput,
149 	.pr_usrreqs =		&rip6_usrreqs
150 };
151 
152 static int ip6_mrouter_ver = 0;
153 
154 SYSCTL_DECL(_net_inet6);
155 SYSCTL_DECL(_net_inet6_ip6);
156 SYSCTL_NODE(_net_inet6, IPPROTO_PIM, pim, CTLFLAG_RW, 0, "PIM");
157 
158 static struct mrt6stat mrt6stat;
159 SYSCTL_STRUCT(_net_inet6_ip6, OID_AUTO, mrt6stat, CTLFLAG_RW,
160     &mrt6stat, mrt6stat,
161     "Multicast Routing Statistics (struct mrt6stat, netinet6/ip6_mroute.h)");
162 
163 #define NO_RTE_FOUND	0x1
164 #define RTE_FOUND	0x2
165 
166 static struct mf6c *mf6ctable[MF6CTBLSIZ];
167 SYSCTL_OPAQUE(_net_inet6_ip6, OID_AUTO, mf6ctable, CTLFLAG_RD,
168     &mf6ctable, sizeof(mf6ctable), "S,*mf6ctable[MF6CTBLSIZ]",
169     "Multicast Forwarding Table (struct *mf6ctable[MF6CTBLSIZ], "
170     "netinet6/ip6_mroute.h)");
171 
172 static u_char n6expire[MF6CTBLSIZ];
173 
174 static struct mif6 mif6table[MAXMIFS];
175 SYSCTL_OPAQUE(_net_inet6_ip6, OID_AUTO, mif6table, CTLFLAG_RD,
176     &mif6table, sizeof(mif6table), "S,vif[MAXMIFS]",
177     "Multicast Interfaces (struct mif[MAXMIFS], netinet6/ip6_mroute.h)");
178 
179 #ifdef MRT6DEBUG
180 static u_int mrt6debug = 0;		/* debug level */
181 #define DEBUG_MFC	0x02
182 #define DEBUG_FORWARD	0x04
183 #define DEBUG_EXPIRE	0x08
184 #define DEBUG_XMIT	0x10
185 #define DEBUG_REG	0x20
186 #define DEBUG_PIM	0x40
187 #endif
188 
189 static void	expire_upcalls(void *);
190 #define	EXPIRE_TIMEOUT	(hz / 4)	/* 4x / second */
191 #define	UPCALL_EXPIRE	6		/* number of timeouts */
192 
193 #ifdef INET
194 #ifdef MROUTING
195 extern struct socket *ip_mrouter;
196 #endif
197 #endif
198 
199 /*
200  * 'Interfaces' associated with decapsulator (so we can tell
201  * packets that went through it from ones that get reflected
202  * by a broken gateway).  Different from IPv4 register_if,
203  * these interfaces are linked into the system ifnet list,
204  * because per-interface IPv6 statistics are maintained in
205  * ifp->if_afdata.  But it does not have any routes point
206  * to them.  I.e., packets can't be sent this way.  They
207  * only exist as a placeholder for multicast source
208  * verification.
209  */
210 static struct ifnet *multicast_register_if6;
211 
212 #define ENCAP_HOPS 64
213 
214 /*
215  * Private variables.
216  */
217 static mifi_t nummifs = 0;
218 static mifi_t reg_mif_num = (mifi_t)-1;
219 
220 static struct pim6stat pim6stat;
221 SYSCTL_STRUCT(_net_inet6_pim, PIM6CTL_STATS, stats, CTLFLAG_RD,
222     &pim6stat, pim6stat,
223     "PIM Statistics (struct pim6stat, netinet6/pim_var.h)");
224 
225 static int pim6;
226 
227 /*
228  * Hash function for a source, group entry
229  */
230 #define MF6CHASH(a, g) MF6CHASHMOD((a).s6_addr32[0] ^ (a).s6_addr32[1] ^ \
231 				   (a).s6_addr32[2] ^ (a).s6_addr32[3] ^ \
232 				   (g).s6_addr32[0] ^ (g).s6_addr32[1] ^ \
233 				   (g).s6_addr32[2] ^ (g).s6_addr32[3])
234 
235 /*
236  * Find a route for a given origin IPv6 address and Multicast group address.
237  */
238 #define MF6CFIND(o, g, rt) do { \
239 	struct mf6c *_rt = mf6ctable[MF6CHASH(o,g)]; \
240 	rt = NULL; \
241 	mrt6stat.mrt6s_mfc_lookups++; \
242 	while (_rt) { \
243 		if (IN6_ARE_ADDR_EQUAL(&_rt->mf6c_origin.sin6_addr, &(o)) && \
244 		    IN6_ARE_ADDR_EQUAL(&_rt->mf6c_mcastgrp.sin6_addr, &(g)) && \
245 		    (_rt->mf6c_stall == NULL)) { \
246 			rt = _rt; \
247 			break; \
248 		} \
249 		_rt = _rt->mf6c_next; \
250 	} \
251 	if (rt == NULL) { \
252 		mrt6stat.mrt6s_mfc_misses++; \
253 	} \
254 } while (/*CONSTCOND*/ 0)
255 
256 /*
257  * Macros to compute elapsed time efficiently
258  * Borrowed from Van Jacobson's scheduling code
259  * XXX: replace with timersub() ?
260  */
261 #define TV_DELTA(a, b, delta) do { \
262 	    int xxs; \
263 		\
264 	    delta = (a).tv_usec - (b).tv_usec; \
265 	    if ((xxs = (a).tv_sec - (b).tv_sec)) { \
266 	       switch (xxs) { \
267 		      case 2: \
268 			  delta += 1000000; \
269 			      /* FALLTHROUGH */ \
270 		      case 1: \
271 			  delta += 1000000; \
272 			  break; \
273 		      default: \
274 			  delta += (1000000 * xxs); \
275 	       } \
276 	    } \
277 } while (/*CONSTCOND*/ 0)
278 
279 /* XXX: replace with timercmp(a, b, <) ? */
280 #define TV_LT(a, b) (((a).tv_usec < (b).tv_usec && \
281 	      (a).tv_sec <= (b).tv_sec) || (a).tv_sec < (b).tv_sec)
282 
283 #ifdef UPCALL_TIMING
284 #define UPCALL_MAX	50
285 static u_long upcall_data[UPCALL_MAX + 1];
286 static void collate();
287 #endif /* UPCALL_TIMING */
288 
289 static int get_sg_cnt(struct sioc_sg_req6 *);
290 static int get_mif6_cnt(struct sioc_mif_req6 *);
291 static int ip6_mrouter_init(struct socket *, int, int);
292 static int add_m6if(struct mif6ctl *);
293 static int del_m6if(mifi_t *);
294 static int add_m6fc(struct mf6cctl *);
295 static int del_m6fc(struct mf6cctl *);
296 
297 static struct callout expire_upcalls_ch;
298 
299 int X_ip6_mforward(struct ip6_hdr *ip6, struct ifnet *ifp, struct mbuf *m);
300 int X_ip6_mrouter_done(void);
301 int X_ip6_mrouter_set(struct socket *so, struct sockopt *sopt);
302 int X_ip6_mrouter_get(struct socket *so, struct sockopt *sopt);
303 int X_mrt6_ioctl(int cmd, caddr_t data);
304 
305 /*
306  * Handle MRT setsockopt commands to modify the multicast routing tables.
307  */
308 int
309 X_ip6_mrouter_set(struct socket *so, struct sockopt *sopt)
310 {
311 	int error = 0;
312 	int optval;
313 	struct mif6ctl mifc;
314 	struct mf6cctl mfcc;
315 	mifi_t mifi;
316 
317 	if (so != ip6_mrouter && sopt->sopt_name != MRT6_INIT)
318 		return (EACCES);
319 
320 	switch (sopt->sopt_name) {
321 	case MRT6_INIT:
322 #ifdef MRT6_OINIT
323 	case MRT6_OINIT:
324 #endif
325 		error = sooptcopyin(sopt, &optval, sizeof(optval),
326 		    sizeof(optval));
327 		if (error)
328 			break;
329 		error = ip6_mrouter_init(so, optval, sopt->sopt_name);
330 		break;
331 	case MRT6_DONE:
332 		error = X_ip6_mrouter_done();
333 		break;
334 	case MRT6_ADD_MIF:
335 		error = sooptcopyin(sopt, &mifc, sizeof(mifc), sizeof(mifc));
336 		if (error)
337 			break;
338 		error = add_m6if(&mifc);
339 		break;
340 	case MRT6_ADD_MFC:
341 		error = sooptcopyin(sopt, &mfcc, sizeof(mfcc), sizeof(mfcc));
342 		if (error)
343 			break;
344 		error = add_m6fc(&mfcc);
345 		break;
346 	case MRT6_DEL_MFC:
347 		error = sooptcopyin(sopt, &mfcc, sizeof(mfcc), sizeof(mfcc));
348 		if (error)
349 			break;
350 		error = del_m6fc(&mfcc);
351 		break;
352 	case MRT6_DEL_MIF:
353 		error = sooptcopyin(sopt, &mifi, sizeof(mifi), sizeof(mifi));
354 		if (error)
355 			break;
356 		error = del_m6if(&mifi);
357 		break;
358 	case MRT6_PIM:
359 		error = sooptcopyin(sopt, &optval, sizeof(optval),
360 		    sizeof(optval));
361 		if (error)
362 			break;
363 		error = set_pim6(&optval);
364 		break;
365 	default:
366 		error = EOPNOTSUPP;
367 		break;
368 	}
369 
370 	return (error);
371 }
372 
373 /*
374  * Handle MRT getsockopt commands
375  */
376 int
377 X_ip6_mrouter_get(struct socket *so, struct sockopt *sopt)
378 {
379 	INIT_VNET_INET6(curvnet);
380 	int error = 0;
381 
382 	if (so != ip6_mrouter)
383 		return (EACCES);
384 
385 	switch (sopt->sopt_name) {
386 		case MRT6_PIM:
387 			error = sooptcopyout(sopt, &V_pim6, sizeof(V_pim6));
388 			break;
389 	}
390 	return (error);
391 }
392 
393 /*
394  * Handle ioctl commands to obtain information from the cache
395  */
396 int
397 X_mrt6_ioctl(int cmd, caddr_t data)
398 {
399 	switch (cmd) {
400 	case SIOCGETSGCNT_IN6:
401 		return (get_sg_cnt((struct sioc_sg_req6 *)data));
402 	case SIOCGETMIFCNT_IN6:
403 		return (get_mif6_cnt((struct sioc_mif_req6 *)data));
404 	default:
405 		return (EINVAL);
406 	}
407 }
408 
409 /*
410  * returns the packet, byte, rpf-failure count for the source group provided
411  */
412 static int
413 get_sg_cnt(struct sioc_sg_req6 *req)
414 {
415 	struct mf6c *rt;
416 	int s;
417 
418 	s = splnet();
419 	MF6CFIND(req->src.sin6_addr, req->grp.sin6_addr, rt);
420 	splx(s);
421 	if (rt != NULL) {
422 		req->pktcnt = rt->mf6c_pkt_cnt;
423 		req->bytecnt = rt->mf6c_byte_cnt;
424 		req->wrong_if = rt->mf6c_wrong_if;
425 	} else
426 		return (ESRCH);
427 #if 0
428 		req->pktcnt = req->bytecnt = req->wrong_if = 0xffffffff;
429 #endif
430 
431 	return (0);
432 }
433 
434 /*
435  * returns the input and output packet and byte counts on the mif provided
436  */
437 static int
438 get_mif6_cnt(struct sioc_mif_req6 *req)
439 {
440 	mifi_t mifi = req->mifi;
441 
442 	if (mifi >= nummifs)
443 		return (EINVAL);
444 
445 	req->icount = mif6table[mifi].m6_pkt_in;
446 	req->ocount = mif6table[mifi].m6_pkt_out;
447 	req->ibytes = mif6table[mifi].m6_bytes_in;
448 	req->obytes = mif6table[mifi].m6_bytes_out;
449 
450 	return (0);
451 }
452 
453 static int
454 set_pim6(int *i)
455 {
456 	INIT_VNET_INET6(curvnet);
457 	if ((*i != 1) && (*i != 0))
458 		return (EINVAL);
459 
460 	V_pim6 = *i;
461 
462 	return (0);
463 }
464 
465 /*
466  * Enable multicast routing
467  */
468 static int
469 ip6_mrouter_init(struct socket *so, int v, int cmd)
470 {
471 	INIT_VNET_INET6(curvnet);
472 
473 #ifdef MRT6DEBUG
474 	if (V_mrt6debug)
475 		log(LOG_DEBUG,
476 		    "ip6_mrouter_init: so_type = %d, pr_protocol = %d\n",
477 		    so->so_type, so->so_proto->pr_protocol);
478 #endif
479 
480 	if (so->so_type != SOCK_RAW ||
481 	    so->so_proto->pr_protocol != IPPROTO_ICMPV6)
482 		return (EOPNOTSUPP);
483 
484 	if (v != 1)
485 		return (ENOPROTOOPT);
486 
487 	if (ip6_mrouter != NULL)
488 		return (EADDRINUSE);
489 
490 	ip6_mrouter = so;
491 	V_ip6_mrouter_ver = cmd;
492 
493 	bzero((caddr_t)mf6ctable, sizeof(mf6ctable));
494 	bzero((caddr_t)n6expire, sizeof(n6expire));
495 
496 	V_pim6 = 0;/* used for stubbing out/in pim stuff */
497 
498 	callout_init(&expire_upcalls_ch, 0);
499 	callout_reset(&expire_upcalls_ch, EXPIRE_TIMEOUT,
500 	    expire_upcalls, NULL);
501 
502 #ifdef MRT6DEBUG
503 	if (V_mrt6debug)
504 		log(LOG_DEBUG, "ip6_mrouter_init\n");
505 #endif
506 
507 	return (0);
508 }
509 
510 /*
511  * Disable multicast routing
512  */
513 int
514 X_ip6_mrouter_done(void)
515 {
516 	INIT_VNET_INET6(curvnet);
517 	mifi_t mifi;
518 	int i;
519 	struct mf6c *rt;
520 	struct rtdetq *rte;
521 	int s;
522 
523 	s = splnet();
524 
525 	/*
526 	 * For each phyint in use, disable promiscuous reception of all IPv6
527 	 * multicasts.
528 	 */
529 #ifdef INET
530 #ifdef MROUTING
531 	/*
532 	 * If there is still IPv4 multicast routing daemon,
533 	 * we remain interfaces to receive all muliticasted packets.
534 	 * XXX: there may be an interface in which the IPv4 multicast
535 	 * daemon is not interested...
536 	 */
537 	if (!V_ip_mrouter)
538 #endif
539 #endif
540 	{
541 		for (mifi = 0; mifi < nummifs; mifi++) {
542 			if (mif6table[mifi].m6_ifp &&
543 			    !(mif6table[mifi].m6_flags & MIFF_REGISTER)) {
544 				if_allmulti(mif6table[mifi].m6_ifp, 0);
545 			}
546 		}
547 	}
548 	bzero((caddr_t)mif6table, sizeof(mif6table));
549 	nummifs = 0;
550 
551 	V_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_MRTABLE6);
568 				rte = n;
569 			}
570 			frt = rt;
571 			rt = rt->mf6c_next;
572 			free(frt, M_MRTABLE6);
573 		}
574 	}
575 
576 	bzero((caddr_t)mf6ctable, sizeof(mf6ctable));
577 
578 	/*
579 	 * Reset register interface
580 	 */
581 	if (reg_mif_num != (mifi_t)-1 && multicast_register_if6 != NULL) {
582 		if_detach(multicast_register_if6);
583 		if_free(multicast_register_if6);
584 		reg_mif_num = (mifi_t)-1;
585 		multicast_register_if6 = NULL;
586 	}
587 
588 	ip6_mrouter = NULL;
589 	V_ip6_mrouter_ver = 0;
590 
591 	splx(s);
592 
593 #ifdef MRT6DEBUG
594 	if (V_mrt6debug)
595 		log(LOG_DEBUG, "ip6_mrouter_done\n");
596 #endif
597 
598 	return (0);
599 }
600 
601 static struct sockaddr_in6 sin6 = { sizeof(sin6), AF_INET6 };
602 
603 /*
604  * Add a mif to the mif table
605  */
606 static int
607 add_m6if(struct mif6ctl *mifcp)
608 {
609 	INIT_VNET_NET(curvnet);
610 	struct mif6 *mifp;
611 	struct ifnet *ifp;
612 	int error, s;
613 
614 	if (mifcp->mif6c_mifi >= MAXMIFS)
615 		return (EINVAL);
616 	mifp = mif6table + mifcp->mif6c_mifi;
617 	if (mifp->m6_ifp)
618 		return (EADDRINUSE); /* XXX: is it appropriate? */
619 	if (mifcp->mif6c_pifi == 0 || mifcp->mif6c_pifi > V_if_index)
620 		return (ENXIO);
621 	ifp = ifnet_byindex(mifcp->mif6c_pifi);
622 
623 	if (mifcp->mif6c_flags & MIFF_REGISTER) {
624 		if (reg_mif_num == (mifi_t)-1) {
625 			ifp = if_alloc(IFT_OTHER);
626 
627 			if_initname(ifp, "register_mif", 0);
628 			ifp->if_flags |= IFF_LOOPBACK;
629 			if_attach(ifp);
630 			multicast_register_if6 = ifp;
631 			reg_mif_num = mifcp->mif6c_mifi;
632 			/*
633 			 * it is impossible to guess the ifindex of the
634 			 * register interface.  So mif6c_pifi is automatically
635 			 * calculated.
636 			 */
637 			mifcp->mif6c_pifi = ifp->if_index;
638 		} else {
639 			ifp = multicast_register_if6;
640 		}
641 
642 	} /* if REGISTER */
643 	else {
644 		/* Make sure the interface supports multicast */
645 		if ((ifp->if_flags & IFF_MULTICAST) == 0)
646 			return (EOPNOTSUPP);
647 
648 		s = splnet();
649 		error = if_allmulti(ifp, 1);
650 		splx(s);
651 		if (error)
652 			return (error);
653 	}
654 
655 	s = splnet();
656 	mifp->m6_flags     = mifcp->mif6c_flags;
657 	mifp->m6_ifp       = ifp;
658 
659 	/* initialize per mif pkt counters */
660 	mifp->m6_pkt_in    = 0;
661 	mifp->m6_pkt_out   = 0;
662 	mifp->m6_bytes_in  = 0;
663 	mifp->m6_bytes_out = 0;
664 	splx(s);
665 
666 	/* Adjust nummifs up if the mifi is higher than nummifs */
667 	if (nummifs <= mifcp->mif6c_mifi)
668 		nummifs = mifcp->mif6c_mifi + 1;
669 
670 #ifdef MRT6DEBUG
671 	if (V_mrt6debug)
672 		log(LOG_DEBUG,
673 		    "add_mif #%d, phyint %s\n",
674 		    mifcp->mif6c_mifi,
675 		    ifp->if_xname);
676 #endif
677 
678 	return (0);
679 }
680 
681 /*
682  * Delete a mif from the mif table
683  */
684 static int
685 del_m6if(mifi_t *mifip)
686 {
687 	struct mif6 *mifp = mif6table + *mifip;
688 	mifi_t mifi;
689 	struct ifnet *ifp;
690 	int s;
691 
692 	if (*mifip >= nummifs)
693 		return (EINVAL);
694 	if (mifp->m6_ifp == NULL)
695 		return (EINVAL);
696 
697 	s = splnet();
698 
699 	if (!(mifp->m6_flags & MIFF_REGISTER)) {
700 		/*
701 		 * XXX: what if there is yet IPv4 multicast daemon
702 		 *      using the interface?
703 		 */
704 		ifp = mifp->m6_ifp;
705 
706 		if_allmulti(ifp, 0);
707 	} else {
708 		if (reg_mif_num != (mifi_t)-1 &&
709 		    multicast_register_if6 != NULL) {
710 			if_detach(multicast_register_if6);
711 			if_free(multicast_register_if6);
712 			reg_mif_num = (mifi_t)-1;
713 			multicast_register_if6 = NULL;
714 		}
715 	}
716 
717 	bzero((caddr_t)mifp, sizeof(*mifp));
718 
719 	/* Adjust nummifs down */
720 	for (mifi = nummifs; mifi > 0; mifi--)
721 		if (mif6table[mifi - 1].m6_ifp)
722 			break;
723 	nummifs = mifi;
724 
725 	splx(s);
726 
727 #ifdef MRT6DEBUG
728 	if (V_mrt6debug)
729 		log(LOG_DEBUG, "del_m6if %d, nummifs %d\n", *mifip, nummifs);
730 #endif
731 
732 	return (0);
733 }
734 
735 /*
736  * Add an mfc entry
737  */
738 static int
739 add_m6fc(struct mf6cctl *mfccp)
740 {
741 	struct mf6c *rt;
742 	u_long hash;
743 	struct rtdetq *rte;
744 	u_short nstl;
745 	int s;
746 	char ip6bufo[INET6_ADDRSTRLEN], ip6bufg[INET6_ADDRSTRLEN];
747 
748 	MF6CFIND(mfccp->mf6cc_origin.sin6_addr,
749 		 mfccp->mf6cc_mcastgrp.sin6_addr, rt);
750 
751 	/* If an entry already exists, just update the fields */
752 	if (rt) {
753 #ifdef MRT6DEBUG
754 		if (V_mrt6debug & DEBUG_MFC) {
755 		    log(LOG_DEBUG,
756 			"add_m6fc no upcall h %d o %s g %s p %x\n",
757 			ip6_sprintf(ip6bufo, &mfccp->mf6cc_origin.sin6_addr),
758 			ip6_sprintf(ip6bufg, &mfccp->mf6cc_mcastgrp.sin6_addr),
759 			mfccp->mf6cc_parent);
760 		}
761 #endif
762 
763 		s = splnet();
764 		rt->mf6c_parent = mfccp->mf6cc_parent;
765 		rt->mf6c_ifset = mfccp->mf6cc_ifset;
766 		splx(s);
767 		return (0);
768 	}
769 
770 	/*
771 	 * Find the entry for which the upcall was made and update
772 	 */
773 	s = splnet();
774 	hash = MF6CHASH(mfccp->mf6cc_origin.sin6_addr,
775 			mfccp->mf6cc_mcastgrp.sin6_addr);
776 	for (rt = mf6ctable[hash], nstl = 0; rt; rt = rt->mf6c_next) {
777 		if (IN6_ARE_ADDR_EQUAL(&rt->mf6c_origin.sin6_addr,
778 				       &mfccp->mf6cc_origin.sin6_addr) &&
779 		    IN6_ARE_ADDR_EQUAL(&rt->mf6c_mcastgrp.sin6_addr,
780 				       &mfccp->mf6cc_mcastgrp.sin6_addr) &&
781 		    (rt->mf6c_stall != NULL)) {
782 
783 			if (nstl++)
784 				log(LOG_ERR,
785 				    "add_m6fc: %s o %s g %s p %x dbx %p\n",
786 				    "multiple kernel entries",
787 				    ip6_sprintf(ip6bufo,
788 					    &mfccp->mf6cc_origin.sin6_addr),
789 				    ip6_sprintf(ip6bufg,
790 					    &mfccp->mf6cc_mcastgrp.sin6_addr),
791 				    mfccp->mf6cc_parent, rt->mf6c_stall);
792 
793 #ifdef MRT6DEBUG
794 			if (V_mrt6debug & DEBUG_MFC)
795 				log(LOG_DEBUG,
796 				    "add_m6fc o %s g %s p %x dbg %x\n",
797 				    ip6_sprintf(ip6bufo,
798 					    &mfccp->mf6cc_origin.sin6_addr),
799 				    ip6_sprintf(ip6bufg,
800 					    &mfccp->mf6cc_mcastgrp.sin6_addr),
801 				    mfccp->mf6cc_parent, rt->mf6c_stall);
802 #endif
803 
804 			rt->mf6c_origin     = mfccp->mf6cc_origin;
805 			rt->mf6c_mcastgrp   = mfccp->mf6cc_mcastgrp;
806 			rt->mf6c_parent     = mfccp->mf6cc_parent;
807 			rt->mf6c_ifset	    = mfccp->mf6cc_ifset;
808 			/* initialize pkt counters per src-grp */
809 			rt->mf6c_pkt_cnt    = 0;
810 			rt->mf6c_byte_cnt   = 0;
811 			rt->mf6c_wrong_if   = 0;
812 
813 			rt->mf6c_expire = 0;	/* Don't clean this guy up */
814 			n6expire[hash]--;
815 
816 			/* free packets Qed at the end of this entry */
817 			for (rte = rt->mf6c_stall; rte != NULL; ) {
818 				struct rtdetq *n = rte->next;
819 				ip6_mdq(rte->m, rte->ifp, rt);
820 				m_freem(rte->m);
821 #ifdef UPCALL_TIMING
822 				collate(&(rte->t));
823 #endif /* UPCALL_TIMING */
824 				free(rte, M_MRTABLE6);
825 				rte = n;
826 			}
827 			rt->mf6c_stall = NULL;
828 		}
829 	}
830 
831 	/*
832 	 * It is possible that an entry is being inserted without an upcall
833 	 */
834 	if (nstl == 0) {
835 #ifdef MRT6DEBUG
836 		if (V_mrt6debug & DEBUG_MFC)
837 		    log(LOG_DEBUG,
838 			"add_mfc no upcall h %d o %s g %s p %x\n",
839 			hash,
840 			ip6_sprintf(ip6bufo, &mfccp->mf6cc_origin.sin6_addr),
841 			ip6_sprintf(ip6bufg, &mfccp->mf6cc_mcastgrp.sin6_addr),
842 			mfccp->mf6cc_parent);
843 #endif
844 
845 		for (rt = mf6ctable[hash]; rt; rt = rt->mf6c_next) {
846 
847 			if (IN6_ARE_ADDR_EQUAL(&rt->mf6c_origin.sin6_addr,
848 					       &mfccp->mf6cc_origin.sin6_addr)&&
849 			    IN6_ARE_ADDR_EQUAL(&rt->mf6c_mcastgrp.sin6_addr,
850 					       &mfccp->mf6cc_mcastgrp.sin6_addr)) {
851 
852 				rt->mf6c_origin     = mfccp->mf6cc_origin;
853 				rt->mf6c_mcastgrp   = mfccp->mf6cc_mcastgrp;
854 				rt->mf6c_parent     = mfccp->mf6cc_parent;
855 				rt->mf6c_ifset	    = mfccp->mf6cc_ifset;
856 				/* initialize pkt counters per src-grp */
857 				rt->mf6c_pkt_cnt    = 0;
858 				rt->mf6c_byte_cnt   = 0;
859 				rt->mf6c_wrong_if   = 0;
860 
861 				if (rt->mf6c_expire)
862 					n6expire[hash]--;
863 				rt->mf6c_expire	   = 0;
864 			}
865 		}
866 		if (rt == NULL) {
867 			/* no upcall, so make a new entry */
868 			rt = (struct mf6c *)malloc(sizeof(*rt), M_MRTABLE6,
869 						  M_NOWAIT);
870 			if (rt == NULL) {
871 				splx(s);
872 				return (ENOBUFS);
873 			}
874 
875 			/* insert new entry at head of hash chain */
876 			rt->mf6c_origin     = mfccp->mf6cc_origin;
877 			rt->mf6c_mcastgrp   = mfccp->mf6cc_mcastgrp;
878 			rt->mf6c_parent     = mfccp->mf6cc_parent;
879 			rt->mf6c_ifset	    = mfccp->mf6cc_ifset;
880 			/* initialize pkt counters per src-grp */
881 			rt->mf6c_pkt_cnt    = 0;
882 			rt->mf6c_byte_cnt   = 0;
883 			rt->mf6c_wrong_if   = 0;
884 			rt->mf6c_expire     = 0;
885 			rt->mf6c_stall = NULL;
886 
887 			/* link into table */
888 			rt->mf6c_next  = mf6ctable[hash];
889 			mf6ctable[hash] = rt;
890 		}
891 	}
892 	splx(s);
893 	return (0);
894 }
895 
896 #ifdef UPCALL_TIMING
897 /*
898  * collect delay statistics on the upcalls
899  */
900 static void
901 collate(struct timeval *t)
902 {
903 	u_long d;
904 	struct timeval tp;
905 	u_long delta;
906 
907 	GET_TIME(tp);
908 
909 	if (TV_LT(*t, tp))
910 	{
911 		TV_DELTA(tp, *t, delta);
912 
913 		d = delta >> 10;
914 		if (d > UPCALL_MAX)
915 			d = UPCALL_MAX;
916 
917 		++upcall_data[d];
918 	}
919 }
920 #endif /* UPCALL_TIMING */
921 
922 /*
923  * Delete an mfc entry
924  */
925 static int
926 del_m6fc(struct mf6cctl *mfccp)
927 {
928 	struct sockaddr_in6	origin;
929 	struct sockaddr_in6	mcastgrp;
930 	struct mf6c		*rt;
931 	struct mf6c		**nptr;
932 	u_long		hash;
933 	int s;
934 
935 	origin = mfccp->mf6cc_origin;
936 	mcastgrp = mfccp->mf6cc_mcastgrp;
937 	hash = MF6CHASH(origin.sin6_addr, mcastgrp.sin6_addr);
938 
939 #ifdef MRT6DEBUG
940 	if (V_mrt6debug & DEBUG_MFC) {
941 		char ip6bufo[INET6_ADDRSTRLEN], ip6bufg[INET6_ADDRSTRLEN];
942 		log(LOG_DEBUG,"del_m6fc orig %s mcastgrp %s\n",
943 		    ip6_sprintf(ip6bufo, &origin.sin6_addr),
944 		    ip6_sprintf(ip6bufg, &mcastgrp.sin6_addr));
945 	}
946 #endif
947 
948 	s = splnet();
949 
950 	nptr = &mf6ctable[hash];
951 	while ((rt = *nptr) != NULL) {
952 		if (IN6_ARE_ADDR_EQUAL(&origin.sin6_addr,
953 				       &rt->mf6c_origin.sin6_addr) &&
954 		    IN6_ARE_ADDR_EQUAL(&mcastgrp.sin6_addr,
955 				       &rt->mf6c_mcastgrp.sin6_addr) &&
956 		    rt->mf6c_stall == NULL)
957 			break;
958 
959 		nptr = &rt->mf6c_next;
960 	}
961 	if (rt == NULL) {
962 		splx(s);
963 		return (EADDRNOTAVAIL);
964 	}
965 
966 	*nptr = rt->mf6c_next;
967 	free(rt, M_MRTABLE6);
968 
969 	splx(s);
970 
971 	return (0);
972 }
973 
974 static int
975 socket_send(struct socket *s, struct mbuf *mm, struct sockaddr_in6 *src)
976 {
977 
978 	if (s) {
979 		if (sbappendaddr(&s->so_rcv,
980 				 (struct sockaddr *)src,
981 				 mm, (struct mbuf *)0) != 0) {
982 			sorwakeup(s);
983 			return (0);
984 		}
985 	}
986 	m_freem(mm);
987 	return (-1);
988 }
989 
990 /*
991  * IPv6 multicast forwarding function. This function assumes that the packet
992  * pointed to by "ip6" has arrived on (or is about to be sent to) the interface
993  * pointed to by "ifp", and the packet is to be relayed to other networks
994  * that have members of the packet's destination IPv6 multicast group.
995  *
996  * The packet is returned unscathed to the caller, unless it is
997  * erroneous, in which case a non-zero return value tells the caller to
998  * discard it.
999  *
1000  * NOTE: this implementation assumes that m->m_pkthdr.rcvif is NULL iff
1001  * this function is called in the originating context (i.e., not when
1002  * forwarding a packet from other node).  ip6_output(), which is currently the
1003  * only function that calls this function is called in the originating context,
1004  * explicitly ensures this condition.  It is caller's responsibility to ensure
1005  * that if this function is called from somewhere else in the originating
1006  * context in the future.
1007  */
1008 int
1009 X_ip6_mforward(struct ip6_hdr *ip6, struct ifnet *ifp, struct mbuf *m)
1010 {
1011 	INIT_VNET_INET6(curvnet);
1012 	struct mf6c *rt;
1013 	struct mif6 *mifp;
1014 	struct mbuf *mm;
1015 	int s;
1016 	mifi_t mifi;
1017 	char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
1018 
1019 #ifdef MRT6DEBUG
1020 	if (V_mrt6debug & DEBUG_FORWARD)
1021 		log(LOG_DEBUG, "ip6_mforward: src %s, dst %s, ifindex %d\n",
1022 		    ip6_sprintf(ip6bufs, &ip6->ip6_src),
1023 		    ip6_sprintf(ip6bufd, &ip6->ip6_dst),
1024 		    ifp->if_index);
1025 #endif
1026 
1027 	/*
1028 	 * Don't forward a packet with Hop limit of zero or one,
1029 	 * or a packet destined to a local-only group.
1030 	 */
1031 	if (ip6->ip6_hlim <= 1 || IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst) ||
1032 	    IN6_IS_ADDR_MC_LINKLOCAL(&ip6->ip6_dst))
1033 		return (0);
1034 	ip6->ip6_hlim--;
1035 
1036 	/*
1037 	 * Source address check: do not forward packets with unspecified
1038 	 * source. It was discussed in July 2000, on ipngwg mailing list.
1039 	 * This is rather more serious than unicast cases, because some
1040 	 * MLD packets can be sent with the unspecified source address
1041 	 * (although such packets must normally set 1 to the hop limit field).
1042 	 */
1043 	if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src)) {
1044 		V_ip6stat.ip6s_cantforward++;
1045 		if (V_ip6_log_time + V_ip6_log_interval < time_second) {
1046 			V_ip6_log_time = time_second;
1047 			log(LOG_DEBUG,
1048 			    "cannot forward "
1049 			    "from %s to %s nxt %d received on %s\n",
1050 			    ip6_sprintf(ip6bufs, &ip6->ip6_src),
1051 			    ip6_sprintf(ip6bufd, &ip6->ip6_dst),
1052 			    ip6->ip6_nxt,
1053 			    if_name(m->m_pkthdr.rcvif));
1054 		}
1055 		return (0);
1056 	}
1057 
1058 	/*
1059 	 * Determine forwarding mifs from the forwarding cache table
1060 	 */
1061 	s = splnet();
1062 	MF6CFIND(ip6->ip6_src, ip6->ip6_dst, rt);
1063 
1064 	/* Entry exists, so forward if necessary */
1065 	if (rt) {
1066 		splx(s);
1067 		return (ip6_mdq(m, ifp, rt));
1068 	} else {
1069 		/*
1070 		 * If we don't have a route for packet's origin,
1071 		 * Make a copy of the packet &
1072 		 * send message to routing daemon
1073 		 */
1074 
1075 		struct mbuf *mb0;
1076 		struct rtdetq *rte;
1077 		u_long hash;
1078 /*		int i, npkts;*/
1079 #ifdef UPCALL_TIMING
1080 		struct timeval tp;
1081 
1082 		GET_TIME(tp);
1083 #endif /* UPCALL_TIMING */
1084 
1085 		mrt6stat.mrt6s_no_route++;
1086 #ifdef MRT6DEBUG
1087 		if (V_mrt6debug & (DEBUG_FORWARD | DEBUG_MFC))
1088 			log(LOG_DEBUG, "ip6_mforward: no rte s %s g %s\n",
1089 			    ip6_sprintf(ip6bufs, &ip6->ip6_src),
1090 			    ip6_sprintf(ip6bufd, &ip6->ip6_dst));
1091 #endif
1092 
1093 		/*
1094 		 * Allocate mbufs early so that we don't do extra work if we
1095 		 * are just going to fail anyway.
1096 		 */
1097 		rte = (struct rtdetq *)malloc(sizeof(*rte), M_MRTABLE6,
1098 					      M_NOWAIT);
1099 		if (rte == NULL) {
1100 			splx(s);
1101 			return (ENOBUFS);
1102 		}
1103 		mb0 = m_copy(m, 0, M_COPYALL);
1104 		/*
1105 		 * Pullup packet header if needed before storing it,
1106 		 * as other references may modify it in the meantime.
1107 		 */
1108 		if (mb0 &&
1109 		    (M_HASCL(mb0) || mb0->m_len < sizeof(struct ip6_hdr)))
1110 			mb0 = m_pullup(mb0, sizeof(struct ip6_hdr));
1111 		if (mb0 == NULL) {
1112 			free(rte, M_MRTABLE6);
1113 			splx(s);
1114 			return (ENOBUFS);
1115 		}
1116 
1117 		/* is there an upcall waiting for this packet? */
1118 		hash = MF6CHASH(ip6->ip6_src, ip6->ip6_dst);
1119 		for (rt = mf6ctable[hash]; rt; rt = rt->mf6c_next) {
1120 			if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_src,
1121 					       &rt->mf6c_origin.sin6_addr) &&
1122 			    IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst,
1123 					       &rt->mf6c_mcastgrp.sin6_addr) &&
1124 			    (rt->mf6c_stall != NULL))
1125 				break;
1126 		}
1127 
1128 		if (rt == NULL) {
1129 			struct mrt6msg *im;
1130 #ifdef MRT6_OINIT
1131 			struct omrt6msg *oim;
1132 #endif
1133 
1134 			/* no upcall, so make a new entry */
1135 			rt = (struct mf6c *)malloc(sizeof(*rt), M_MRTABLE6,
1136 						  M_NOWAIT);
1137 			if (rt == NULL) {
1138 				free(rte, M_MRTABLE6);
1139 				m_freem(mb0);
1140 				splx(s);
1141 				return (ENOBUFS);
1142 			}
1143 			/*
1144 			 * Make a copy of the header to send to the user
1145 			 * level process
1146 			 */
1147 			mm = m_copy(mb0, 0, sizeof(struct ip6_hdr));
1148 
1149 			if (mm == NULL) {
1150 				free(rte, M_MRTABLE6);
1151 				m_freem(mb0);
1152 				free(rt, M_MRTABLE6);
1153 				splx(s);
1154 				return (ENOBUFS);
1155 			}
1156 
1157 			/*
1158 			 * Send message to routing daemon
1159 			 */
1160 			sin6.sin6_addr = ip6->ip6_src;
1161 
1162 			im = NULL;
1163 #ifdef MRT6_OINIT
1164 			oim = NULL;
1165 #endif
1166 			switch (V_ip6_mrouter_ver) {
1167 #ifdef MRT6_OINIT
1168 			case MRT6_OINIT:
1169 				oim = mtod(mm, struct omrt6msg *);
1170 				oim->im6_msgtype = MRT6MSG_NOCACHE;
1171 				oim->im6_mbz = 0;
1172 				break;
1173 #endif
1174 			case MRT6_INIT:
1175 				im = mtod(mm, struct mrt6msg *);
1176 				im->im6_msgtype = MRT6MSG_NOCACHE;
1177 				im->im6_mbz = 0;
1178 				break;
1179 			default:
1180 				free(rte, M_MRTABLE6);
1181 				m_freem(mb0);
1182 				free(rt, M_MRTABLE6);
1183 				splx(s);
1184 				return (EINVAL);
1185 			}
1186 
1187 #ifdef MRT6DEBUG
1188 			if (V_mrt6debug & DEBUG_FORWARD)
1189 				log(LOG_DEBUG,
1190 				    "getting the iif info in the kernel\n");
1191 #endif
1192 
1193 			for (mifp = mif6table, mifi = 0;
1194 			     mifi < nummifs && mifp->m6_ifp != ifp;
1195 			     mifp++, mifi++)
1196 				;
1197 
1198 			switch (V_ip6_mrouter_ver) {
1199 #ifdef MRT6_OINIT
1200 			case MRT6_OINIT:
1201 				oim->im6_mif = mifi;
1202 				break;
1203 #endif
1204 			case MRT6_INIT:
1205 				im->im6_mif = mifi;
1206 				break;
1207 			}
1208 
1209 			if (socket_send(ip6_mrouter, mm, &sin6) < 0) {
1210 				log(LOG_WARNING, "ip6_mforward: ip6_mrouter "
1211 				    "socket queue full\n");
1212 				mrt6stat.mrt6s_upq_sockfull++;
1213 				free(rte, M_MRTABLE6);
1214 				m_freem(mb0);
1215 				free(rt, M_MRTABLE6);
1216 				splx(s);
1217 				return (ENOBUFS);
1218 			}
1219 
1220 			mrt6stat.mrt6s_upcalls++;
1221 
1222 			/* insert new entry at head of hash chain */
1223 			bzero(rt, sizeof(*rt));
1224 			rt->mf6c_origin.sin6_family = AF_INET6;
1225 			rt->mf6c_origin.sin6_len = sizeof(struct sockaddr_in6);
1226 			rt->mf6c_origin.sin6_addr = ip6->ip6_src;
1227 			rt->mf6c_mcastgrp.sin6_family = AF_INET6;
1228 			rt->mf6c_mcastgrp.sin6_len = sizeof(struct sockaddr_in6);
1229 			rt->mf6c_mcastgrp.sin6_addr = ip6->ip6_dst;
1230 			rt->mf6c_expire = UPCALL_EXPIRE;
1231 			n6expire[hash]++;
1232 			rt->mf6c_parent = MF6C_INCOMPLETE_PARENT;
1233 
1234 			/* link into table */
1235 			rt->mf6c_next  = mf6ctable[hash];
1236 			mf6ctable[hash] = rt;
1237 			/* Add this entry to the end of the queue */
1238 			rt->mf6c_stall = rte;
1239 		} else {
1240 			/* determine if q has overflowed */
1241 			struct rtdetq **p;
1242 			int npkts = 0;
1243 
1244 			for (p = &rt->mf6c_stall; *p != NULL; p = &(*p)->next)
1245 				if (++npkts > MAX_UPQ6) {
1246 					mrt6stat.mrt6s_upq_ovflw++;
1247 					free(rte, M_MRTABLE6);
1248 					m_freem(mb0);
1249 					splx(s);
1250 					return (0);
1251 				}
1252 
1253 			/* Add this entry to the end of the queue */
1254 			*p = rte;
1255 		}
1256 
1257 		rte->next = NULL;
1258 		rte->m = mb0;
1259 		rte->ifp = ifp;
1260 #ifdef UPCALL_TIMING
1261 		rte->t = tp;
1262 #endif /* UPCALL_TIMING */
1263 
1264 		splx(s);
1265 
1266 		return (0);
1267 	}
1268 }
1269 
1270 /*
1271  * Clean up cache entries if upcalls are not serviced
1272  * Call from the Slow Timeout mechanism, every half second.
1273  */
1274 static void
1275 expire_upcalls(void *unused)
1276 {
1277 	struct rtdetq *rte;
1278 	struct mf6c *mfc, **nptr;
1279 	int i;
1280 	int s;
1281 
1282 	s = splnet();
1283 	for (i = 0; i < MF6CTBLSIZ; i++) {
1284 		if (n6expire[i] == 0)
1285 			continue;
1286 		nptr = &mf6ctable[i];
1287 		while ((mfc = *nptr) != NULL) {
1288 			rte = mfc->mf6c_stall;
1289 			/*
1290 			 * Skip real cache entries
1291 			 * Make sure it wasn't marked to not expire (shouldn't happen)
1292 			 * If it expires now
1293 			 */
1294 			if (rte != NULL &&
1295 			    mfc->mf6c_expire != 0 &&
1296 			    --mfc->mf6c_expire == 0) {
1297 #ifdef MRT6DEBUG
1298 				if (V_mrt6debug & DEBUG_EXPIRE) {
1299 					char ip6bufo[INET6_ADDRSTRLEN];
1300 					char ip6bufg[INET6_ADDRSTRLEN];
1301 					log(LOG_DEBUG, "expire_upcalls: expiring (%s %s)\n",
1302 					    ip6_sprintf(ip6bufo, &mfc->mf6c_origin.sin6_addr),
1303 					    ip6_sprintf(ip6bufg, &mfc->mf6c_mcastgrp.sin6_addr));
1304 				}
1305 #endif
1306 				/*
1307 				 * drop all the packets
1308 				 * free the mbuf with the pkt, if, timing info
1309 				 */
1310 				do {
1311 					struct rtdetq *n = rte->next;
1312 					m_freem(rte->m);
1313 					free(rte, M_MRTABLE6);
1314 					rte = n;
1315 				} while (rte != NULL);
1316 				mrt6stat.mrt6s_cache_cleanups++;
1317 				n6expire[i]--;
1318 
1319 				*nptr = mfc->mf6c_next;
1320 				free(mfc, M_MRTABLE6);
1321 			} else {
1322 				nptr = &mfc->mf6c_next;
1323 			}
1324 		}
1325 	}
1326 	splx(s);
1327 	callout_reset(&expire_upcalls_ch, EXPIRE_TIMEOUT,
1328 	    expire_upcalls, NULL);
1329 }
1330 
1331 /*
1332  * Packet forwarding routine once entry in the cache is made
1333  */
1334 static int
1335 ip6_mdq(struct mbuf *m, struct ifnet *ifp, struct mf6c *rt)
1336 {
1337 	INIT_VNET_INET6(curvnet);
1338 	struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1339 	mifi_t mifi, iif;
1340 	struct mif6 *mifp;
1341 	int plen = m->m_pkthdr.len;
1342 	struct in6_addr src0, dst0; /* copies for local work */
1343 	u_int32_t iszone, idzone, oszone, odzone;
1344 	int error = 0;
1345 
1346 /*
1347  * Macro to send packet on mif.  Since RSVP packets don't get counted on
1348  * input, they shouldn't get counted on output, so statistics keeping is
1349  * separate.
1350  */
1351 
1352 #define MC6_SEND(ip6, mifp, m) do {				\
1353 	if ((mifp)->m6_flags & MIFF_REGISTER)			\
1354 		register_send((ip6), (mifp), (m));		\
1355 	else							\
1356 		phyint_send((ip6), (mifp), (m));		\
1357 } while (/*CONSTCOND*/ 0)
1358 
1359 	/*
1360 	 * Don't forward if it didn't arrive from the parent mif
1361 	 * for its origin.
1362 	 */
1363 	mifi = rt->mf6c_parent;
1364 	if ((mifi >= nummifs) || (mif6table[mifi].m6_ifp != ifp)) {
1365 		/* came in the wrong interface */
1366 #ifdef MRT6DEBUG
1367 		if (V_mrt6debug & DEBUG_FORWARD)
1368 			log(LOG_DEBUG,
1369 			    "wrong if: ifid %d mifi %d mififid %x\n",
1370 			    ifp->if_index, mifi,
1371 			    mif6table[mifi].m6_ifp->if_index);
1372 #endif
1373 		mrt6stat.mrt6s_wrong_if++;
1374 		rt->mf6c_wrong_if++;
1375 		/*
1376 		 * If we are doing PIM processing, and we are forwarding
1377 		 * packets on this interface, send a message to the
1378 		 * routing daemon.
1379 		 */
1380 		/* have to make sure this is a valid mif */
1381 		if (mifi < nummifs && mif6table[mifi].m6_ifp)
1382 			if (V_pim6 && (m->m_flags & M_LOOP) == 0) {
1383 				/*
1384 				 * Check the M_LOOP flag to avoid an
1385 				 * unnecessary PIM assert.
1386 				 * XXX: M_LOOP is an ad-hoc hack...
1387 				 */
1388 				static struct sockaddr_in6 sin6 =
1389 				{ sizeof(sin6), AF_INET6 };
1390 
1391 				struct mbuf *mm;
1392 				struct mrt6msg *im;
1393 #ifdef MRT6_OINIT
1394 				struct omrt6msg *oim;
1395 #endif
1396 
1397 				mm = m_copy(m, 0, sizeof(struct ip6_hdr));
1398 				if (mm &&
1399 				    (M_HASCL(mm) ||
1400 				     mm->m_len < sizeof(struct ip6_hdr)))
1401 					mm = m_pullup(mm, sizeof(struct ip6_hdr));
1402 				if (mm == NULL)
1403 					return (ENOBUFS);
1404 
1405 #ifdef MRT6_OINIT
1406 				oim = NULL;
1407 #endif
1408 				im = NULL;
1409 				switch (V_ip6_mrouter_ver) {
1410 #ifdef MRT6_OINIT
1411 				case MRT6_OINIT:
1412 					oim = mtod(mm, struct omrt6msg *);
1413 					oim->im6_msgtype = MRT6MSG_WRONGMIF;
1414 					oim->im6_mbz = 0;
1415 					break;
1416 #endif
1417 				case MRT6_INIT:
1418 					im = mtod(mm, struct mrt6msg *);
1419 					im->im6_msgtype = MRT6MSG_WRONGMIF;
1420 					im->im6_mbz = 0;
1421 					break;
1422 				default:
1423 					m_freem(mm);
1424 					return (EINVAL);
1425 				}
1426 
1427 				for (mifp = mif6table, iif = 0;
1428 				     iif < nummifs && mifp &&
1429 					     mifp->m6_ifp != ifp;
1430 				     mifp++, iif++)
1431 					;
1432 
1433 				switch (V_ip6_mrouter_ver) {
1434 #ifdef MRT6_OINIT
1435 				case MRT6_OINIT:
1436 					oim->im6_mif = iif;
1437 					sin6.sin6_addr = oim->im6_src;
1438 					break;
1439 #endif
1440 				case MRT6_INIT:
1441 					im->im6_mif = iif;
1442 					sin6.sin6_addr = im->im6_src;
1443 					break;
1444 				}
1445 
1446 				mrt6stat.mrt6s_upcalls++;
1447 
1448 				if (socket_send(ip6_mrouter, mm, &sin6) < 0) {
1449 #ifdef MRT6DEBUG
1450 					if (V_mrt6debug)
1451 						log(LOG_WARNING, "mdq, ip6_mrouter socket queue full\n");
1452 #endif
1453 					++mrt6stat.mrt6s_upq_sockfull;
1454 					return (ENOBUFS);
1455 				}	/* if socket Q full */
1456 			}		/* if PIM */
1457 		return (0);
1458 	}			/* if wrong iif */
1459 
1460 	/* If I sourced this packet, it counts as output, else it was input. */
1461 	if (m->m_pkthdr.rcvif == NULL) {
1462 		/* XXX: is rcvif really NULL when output?? */
1463 		mif6table[mifi].m6_pkt_out++;
1464 		mif6table[mifi].m6_bytes_out += plen;
1465 	} else {
1466 		mif6table[mifi].m6_pkt_in++;
1467 		mif6table[mifi].m6_bytes_in += plen;
1468 	}
1469 	rt->mf6c_pkt_cnt++;
1470 	rt->mf6c_byte_cnt += plen;
1471 
1472 	/*
1473 	 * For each mif, forward a copy of the packet if there are group
1474 	 * members downstream on the interface.
1475 	 */
1476 	src0 = ip6->ip6_src;
1477 	dst0 = ip6->ip6_dst;
1478 	if ((error = in6_setscope(&src0, ifp, &iszone)) != 0 ||
1479 	    (error = in6_setscope(&dst0, ifp, &idzone)) != 0) {
1480 		V_ip6stat.ip6s_badscope++;
1481 		return (error);
1482 	}
1483 	for (mifp = mif6table, mifi = 0; mifi < nummifs; mifp++, mifi++) {
1484 		if (IF_ISSET(mifi, &rt->mf6c_ifset)) {
1485 			/*
1486 			 * check if the outgoing packet is going to break
1487 			 * a scope boundary.
1488 			 * XXX For packets through PIM register tunnel
1489 			 * interface, we believe a routing daemon.
1490 			 */
1491 			if (!(mif6table[rt->mf6c_parent].m6_flags &
1492 			      MIFF_REGISTER) &&
1493 			    !(mif6table[mifi].m6_flags & MIFF_REGISTER)) {
1494 				if (in6_setscope(&src0, mif6table[mifi].m6_ifp,
1495 				    &oszone) ||
1496 				    in6_setscope(&dst0, mif6table[mifi].m6_ifp,
1497 				    &odzone) ||
1498 				    iszone != oszone ||
1499 				    idzone != odzone) {
1500 					V_ip6stat.ip6s_badscope++;
1501 					continue;
1502 				}
1503 			}
1504 
1505 			mifp->m6_pkt_out++;
1506 			mifp->m6_bytes_out += plen;
1507 			MC6_SEND(ip6, mifp, m);
1508 		}
1509 	}
1510 	return (0);
1511 }
1512 
1513 static void
1514 phyint_send(struct ip6_hdr *ip6, struct mif6 *mifp, struct mbuf *m)
1515 {
1516 	INIT_VNET_INET6(curvnet);
1517 	struct mbuf *mb_copy;
1518 	struct ifnet *ifp = mifp->m6_ifp;
1519 	int error = 0;
1520 	int s = splnet();	/* needs to protect static "ro" below. */
1521 	static struct route_in6 ro;
1522 	struct	in6_multi *in6m;
1523 	struct sockaddr_in6 *dst6;
1524 	u_long linkmtu;
1525 
1526 	/*
1527 	 * Make a new reference to the packet; make sure that
1528 	 * the IPv6 header is actually copied, not just referenced,
1529 	 * so that ip6_output() only scribbles on the copy.
1530 	 */
1531 	mb_copy = m_copy(m, 0, M_COPYALL);
1532 	if (mb_copy &&
1533 	    (M_HASCL(mb_copy) || mb_copy->m_len < sizeof(struct ip6_hdr)))
1534 		mb_copy = m_pullup(mb_copy, sizeof(struct ip6_hdr));
1535 	if (mb_copy == NULL) {
1536 		splx(s);
1537 		return;
1538 	}
1539 	/* set MCAST flag to the outgoing packet */
1540 	mb_copy->m_flags |= M_MCAST;
1541 
1542 	/*
1543 	 * If we sourced the packet, call ip6_output since we may devide
1544 	 * the packet into fragments when the packet is too big for the
1545 	 * outgoing interface.
1546 	 * Otherwise, we can simply send the packet to the interface
1547 	 * sending queue.
1548 	 */
1549 	if (m->m_pkthdr.rcvif == NULL) {
1550 		struct ip6_moptions im6o;
1551 
1552 		im6o.im6o_multicast_ifp = ifp;
1553 		/* XXX: ip6_output will override ip6->ip6_hlim */
1554 		im6o.im6o_multicast_hlim = ip6->ip6_hlim;
1555 		im6o.im6o_multicast_loop = 1;
1556 		error = ip6_output(mb_copy, NULL, &ro,
1557 				   IPV6_FORWARDING, &im6o, NULL, NULL);
1558 
1559 #ifdef MRT6DEBUG
1560 		if (V_mrt6debug & DEBUG_XMIT)
1561 			log(LOG_DEBUG, "phyint_send on mif %d err %d\n",
1562 			    mifp - mif6table, error);
1563 #endif
1564 		splx(s);
1565 		return;
1566 	}
1567 
1568 	/*
1569 	 * If we belong to the destination multicast group
1570 	 * on the outgoing interface, loop back a copy.
1571 	 */
1572 	dst6 = (struct sockaddr_in6 *)&ro.ro_dst;
1573 	IN6_LOOKUP_MULTI(ip6->ip6_dst, ifp, in6m);
1574 	if (in6m != NULL) {
1575 		dst6->sin6_len = sizeof(struct sockaddr_in6);
1576 		dst6->sin6_family = AF_INET6;
1577 		dst6->sin6_addr = ip6->ip6_dst;
1578 		ip6_mloopback(ifp, m, (struct sockaddr_in6 *)&ro.ro_dst);
1579 	}
1580 	/*
1581 	 * Put the packet into the sending queue of the outgoing interface
1582 	 * if it would fit in the MTU of the interface.
1583 	 */
1584 	linkmtu = IN6_LINKMTU(ifp);
1585 	if (mb_copy->m_pkthdr.len <= linkmtu || linkmtu < IPV6_MMTU) {
1586 		dst6->sin6_len = sizeof(struct sockaddr_in6);
1587 		dst6->sin6_family = AF_INET6;
1588 		dst6->sin6_addr = ip6->ip6_dst;
1589 		/*
1590 		 * We just call if_output instead of nd6_output here, since
1591 		 * we need no ND for a multicast forwarded packet...right?
1592 		 */
1593 		error = (*ifp->if_output)(ifp, mb_copy,
1594 		    (struct sockaddr *)&ro.ro_dst, NULL);
1595 #ifdef MRT6DEBUG
1596 		if (V_mrt6debug & DEBUG_XMIT)
1597 			log(LOG_DEBUG, "phyint_send on mif %d err %d\n",
1598 			    mifp - mif6table, error);
1599 #endif
1600 	} else {
1601 		/*
1602 		 * pMTU discovery is intentionally disabled by default, since
1603 		 * various router may notify pMTU in multicast, which can be
1604 		 * a DDoS to a router
1605 		 */
1606 		if (V_ip6_mcast_pmtu)
1607 			icmp6_error(mb_copy, ICMP6_PACKET_TOO_BIG, 0, linkmtu);
1608 		else {
1609 #ifdef MRT6DEBUG
1610 			if (V_mrt6debug & DEBUG_XMIT) {
1611 				char ip6bufs[INET6_ADDRSTRLEN];
1612 				char ip6bufd[INET6_ADDRSTRLEN];
1613 				log(LOG_DEBUG,
1614 				    "phyint_send: packet too big on %s o %s "
1615 				    "g %s size %d(discarded)\n",
1616 				    if_name(ifp),
1617 				    ip6_sprintf(ip6bufs, &ip6->ip6_src),
1618 				    ip6_sprintf(ip6bufd, &ip6->ip6_dst),
1619 				    mb_copy->m_pkthdr.len);
1620 			}
1621 #endif /* MRT6DEBUG */
1622 			m_freem(mb_copy); /* simply discard the packet */
1623 		}
1624 	}
1625 
1626 	splx(s);
1627 }
1628 
1629 static int
1630 register_send(struct ip6_hdr *ip6, struct mif6 *mif, struct mbuf *m)
1631 {
1632 	struct mbuf *mm;
1633 	int i, len = m->m_pkthdr.len;
1634 	static struct sockaddr_in6 sin6 = { sizeof(sin6), AF_INET6 };
1635 	struct mrt6msg *im6;
1636 
1637 #ifdef MRT6DEBUG
1638 	if (V_mrt6debug) {
1639 		char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
1640 		log(LOG_DEBUG, "** IPv6 register_send **\n src %s dst %s\n",
1641 		    ip6_sprintf(ip6bufs, &ip6->ip6_src),
1642 		    ip6_sprintf(ip6bufd, &ip6->ip6_dst));
1643 	}
1644 #endif
1645 	++pim6stat.pim6s_snd_registers;
1646 
1647 	/* Make a copy of the packet to send to the user level process */
1648 	MGETHDR(mm, M_DONTWAIT, MT_HEADER);
1649 	if (mm == NULL)
1650 		return (ENOBUFS);
1651 	mm->m_pkthdr.rcvif = NULL;
1652 	mm->m_data += max_linkhdr;
1653 	mm->m_len = sizeof(struct ip6_hdr);
1654 
1655 	if ((mm->m_next = m_copy(m, 0, M_COPYALL)) == NULL) {
1656 		m_freem(mm);
1657 		return (ENOBUFS);
1658 	}
1659 	i = MHLEN - M_LEADINGSPACE(mm);
1660 	if (i > len)
1661 		i = len;
1662 	mm = m_pullup(mm, i);
1663 	if (mm == NULL)
1664 		return (ENOBUFS);
1665 /* TODO: check it! */
1666 	mm->m_pkthdr.len = len + sizeof(struct ip6_hdr);
1667 
1668 	/*
1669 	 * Send message to routing daemon
1670 	 */
1671 	sin6.sin6_addr = ip6->ip6_src;
1672 
1673 	im6 = mtod(mm, struct mrt6msg *);
1674 	im6->im6_msgtype      = MRT6MSG_WHOLEPKT;
1675 	im6->im6_mbz          = 0;
1676 
1677 	im6->im6_mif = mif - mif6table;
1678 
1679 	/* iif info is not given for reg. encap.n */
1680 	mrt6stat.mrt6s_upcalls++;
1681 
1682 	if (socket_send(ip6_mrouter, mm, &sin6) < 0) {
1683 #ifdef MRT6DEBUG
1684 		if (V_mrt6debug)
1685 			log(LOG_WARNING,
1686 			    "register_send: ip6_mrouter socket queue full\n");
1687 #endif
1688 		++mrt6stat.mrt6s_upq_sockfull;
1689 		return (ENOBUFS);
1690 	}
1691 	return (0);
1692 }
1693 
1694 /*
1695  * PIM sparse mode hook
1696  * Receives the pim control messages, and passes them up to the listening
1697  * socket, using rip6_input.
1698  * The only message processed is the REGISTER pim message; the pim header
1699  * is stripped off, and the inner packet is passed to register_mforward.
1700  */
1701 int
1702 pim6_input(struct mbuf **mp, int *offp, int proto)
1703 {
1704 	INIT_VNET_INET6(curvnet);
1705 	struct pim *pim; /* pointer to a pim struct */
1706 	struct ip6_hdr *ip6;
1707 	int pimlen;
1708 	struct mbuf *m = *mp;
1709 	int minlen;
1710 	int off = *offp;
1711 
1712 	++pim6stat.pim6s_rcv_total;
1713 
1714 	ip6 = mtod(m, struct ip6_hdr *);
1715 	pimlen = m->m_pkthdr.len - *offp;
1716 
1717 	/*
1718 	 * Validate lengths
1719 	 */
1720 	if (pimlen < PIM_MINLEN) {
1721 		++pim6stat.pim6s_rcv_tooshort;
1722 #ifdef MRT6DEBUG
1723 		if (V_mrt6debug & DEBUG_PIM)
1724 			log(LOG_DEBUG,"pim6_input: PIM packet too short\n");
1725 #endif
1726 		m_freem(m);
1727 		return (IPPROTO_DONE);
1728 	}
1729 
1730 	/*
1731 	 * if the packet is at least as big as a REGISTER, go ahead
1732 	 * and grab the PIM REGISTER header size, to avoid another
1733 	 * possible m_pullup() later.
1734 	 *
1735 	 * PIM_MINLEN       == pimhdr + u_int32 == 8
1736 	 * PIM6_REG_MINLEN   == pimhdr + reghdr + eip6hdr == 4 + 4 + 40
1737 	 */
1738 	minlen = (pimlen >= PIM6_REG_MINLEN) ? PIM6_REG_MINLEN : PIM_MINLEN;
1739 
1740 	/*
1741 	 * Make sure that the IP6 and PIM headers in contiguous memory, and
1742 	 * possibly the PIM REGISTER header
1743 	 */
1744 #ifndef PULLDOWN_TEST
1745 	IP6_EXTHDR_CHECK(m, off, minlen, IPPROTO_DONE);
1746 	/* adjust pointer */
1747 	ip6 = mtod(m, struct ip6_hdr *);
1748 
1749 	/* adjust mbuf to point to the PIM header */
1750 	pim = (struct pim *)((caddr_t)ip6 + off);
1751 #else
1752 	IP6_EXTHDR_GET(pim, struct pim *, m, off, minlen);
1753 	if (pim == NULL) {
1754 		pim6stat.pim6s_rcv_tooshort++;
1755 		return (IPPROTO_DONE);
1756 	}
1757 #endif
1758 
1759 #define PIM6_CHECKSUM
1760 #ifdef PIM6_CHECKSUM
1761 	{
1762 		int cksumlen;
1763 
1764 		/*
1765 		 * Validate checksum.
1766 		 * If PIM REGISTER, exclude the data packet
1767 		 */
1768 		if (pim->pim_type == PIM_REGISTER)
1769 			cksumlen = PIM_MINLEN;
1770 		else
1771 			cksumlen = pimlen;
1772 
1773 		if (in6_cksum(m, IPPROTO_PIM, off, cksumlen)) {
1774 			++pim6stat.pim6s_rcv_badsum;
1775 #ifdef MRT6DEBUG
1776 			if (V_mrt6debug & DEBUG_PIM)
1777 				log(LOG_DEBUG,
1778 				    "pim6_input: invalid checksum\n");
1779 #endif
1780 			m_freem(m);
1781 			return (IPPROTO_DONE);
1782 		}
1783 	}
1784 #endif /* PIM_CHECKSUM */
1785 
1786 	/* PIM version check */
1787 	if (pim->pim_ver != PIM_VERSION) {
1788 		++pim6stat.pim6s_rcv_badversion;
1789 #ifdef MRT6DEBUG
1790 		log(LOG_ERR,
1791 		    "pim6_input: incorrect version %d, expecting %d\n",
1792 		    pim->pim_ver, PIM_VERSION);
1793 #endif
1794 		m_freem(m);
1795 		return (IPPROTO_DONE);
1796 	}
1797 
1798 	if (pim->pim_type == PIM_REGISTER) {
1799 		/*
1800 		 * since this is a REGISTER, we'll make a copy of the register
1801 		 * headers ip6+pim+u_int32_t+encap_ip6, to be passed up to the
1802 		 * routing daemon.
1803 		 */
1804 		static struct sockaddr_in6 dst = { sizeof(dst), AF_INET6 };
1805 
1806 		struct mbuf *mcp;
1807 		struct ip6_hdr *eip6;
1808 		u_int32_t *reghdr;
1809 		int rc;
1810 #ifdef MRT6DEBUG
1811 		char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
1812 #endif
1813 
1814 		++pim6stat.pim6s_rcv_registers;
1815 
1816 		if ((reg_mif_num >= nummifs) || (reg_mif_num == (mifi_t) -1)) {
1817 #ifdef MRT6DEBUG
1818 			if (V_mrt6debug & DEBUG_PIM)
1819 				log(LOG_DEBUG,
1820 				    "pim6_input: register mif not set: %d\n",
1821 				    reg_mif_num);
1822 #endif
1823 			m_freem(m);
1824 			return (IPPROTO_DONE);
1825 		}
1826 
1827 		reghdr = (u_int32_t *)(pim + 1);
1828 
1829 		if ((ntohl(*reghdr) & PIM_NULL_REGISTER))
1830 			goto pim6_input_to_daemon;
1831 
1832 		/*
1833 		 * Validate length
1834 		 */
1835 		if (pimlen < PIM6_REG_MINLEN) {
1836 			++pim6stat.pim6s_rcv_tooshort;
1837 			++pim6stat.pim6s_rcv_badregisters;
1838 #ifdef MRT6DEBUG
1839 			log(LOG_ERR,
1840 			    "pim6_input: register packet size too "
1841 			    "small %d from %s\n",
1842 			    pimlen, ip6_sprintf(ip6bufs, &ip6->ip6_src));
1843 #endif
1844 			m_freem(m);
1845 			return (IPPROTO_DONE);
1846 		}
1847 
1848 		eip6 = (struct ip6_hdr *) (reghdr + 1);
1849 #ifdef MRT6DEBUG
1850 		if (V_mrt6debug & DEBUG_PIM)
1851 			log(LOG_DEBUG,
1852 			    "pim6_input[register], eip6: %s -> %s, "
1853 			    "eip6 plen %d\n",
1854 			    ip6_sprintf(ip6bufs, &eip6->ip6_src),
1855 			    ip6_sprintf(ip6bufd, &eip6->ip6_dst),
1856 			    ntohs(eip6->ip6_plen));
1857 #endif
1858 
1859 		/* verify the version number of the inner packet */
1860 		if ((eip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
1861 			++pim6stat.pim6s_rcv_badregisters;
1862 #ifdef MRT6DEBUG
1863 			log(LOG_DEBUG, "pim6_input: invalid IP version (%d) "
1864 			    "of the inner packet\n",
1865 			    (eip6->ip6_vfc & IPV6_VERSION));
1866 #endif
1867 			m_freem(m);
1868 			return (IPPROTO_NONE);
1869 		}
1870 
1871 		/* verify the inner packet is destined to a mcast group */
1872 		if (!IN6_IS_ADDR_MULTICAST(&eip6->ip6_dst)) {
1873 			++pim6stat.pim6s_rcv_badregisters;
1874 #ifdef MRT6DEBUG
1875 			if (V_mrt6debug & DEBUG_PIM)
1876 				log(LOG_DEBUG,
1877 				    "pim6_input: inner packet of register "
1878 				    "is not multicast %s\n",
1879 				    ip6_sprintf(ip6bufd, &eip6->ip6_dst));
1880 #endif
1881 			m_freem(m);
1882 			return (IPPROTO_DONE);
1883 		}
1884 
1885 		/*
1886 		 * make a copy of the whole header to pass to the daemon later.
1887 		 */
1888 		mcp = m_copy(m, 0, off + PIM6_REG_MINLEN);
1889 		if (mcp == NULL) {
1890 #ifdef MRT6DEBUG
1891 			log(LOG_ERR,
1892 			    "pim6_input: pim register: "
1893 			    "could not copy register head\n");
1894 #endif
1895 			m_freem(m);
1896 			return (IPPROTO_DONE);
1897 		}
1898 
1899 		/*
1900 		 * forward the inner ip6 packet; point m_data at the inner ip6.
1901 		 */
1902 		m_adj(m, off + PIM_MINLEN);
1903 #ifdef MRT6DEBUG
1904 		if (V_mrt6debug & DEBUG_PIM) {
1905 			log(LOG_DEBUG,
1906 			    "pim6_input: forwarding decapsulated register: "
1907 			    "src %s, dst %s, mif %d\n",
1908 			    ip6_sprintf(ip6bufs, &eip6->ip6_src),
1909 			    ip6_sprintf(ip6bufd, &eip6->ip6_dst),
1910 			    reg_mif_num);
1911 		}
1912 #endif
1913 
1914 		rc = if_simloop(mif6table[reg_mif_num].m6_ifp, m,
1915 				dst.sin6_family, 0);
1916 
1917 		/* prepare the register head to send to the mrouting daemon */
1918 		m = mcp;
1919 	}
1920 
1921 	/*
1922 	 * Pass the PIM message up to the daemon; if it is a register message
1923 	 * pass the 'head' only up to the daemon. This includes the
1924 	 * encapsulator ip6 header, pim header, register header and the
1925 	 * encapsulated ip6 header.
1926 	 */
1927   pim6_input_to_daemon:
1928 	rip6_input(&m, offp, proto);
1929 	return (IPPROTO_DONE);
1930 }
1931