xref: /freebsd/sys/netinet6/ip6_mroute.c (revision d4ae33f0721c1b170fe37d97e395228ffcfb3f80)
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_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/module.h>
94 #include <sys/domain.h>
95 #include <sys/protosw.h>
96 #include <sys/sdt.h>
97 #include <sys/signalvar.h>
98 #include <sys/socket.h>
99 #include <sys/socketvar.h>
100 #include <sys/sockio.h>
101 #include <sys/sx.h>
102 #include <sys/sysctl.h>
103 #include <sys/syslog.h>
104 #include <sys/systm.h>
105 #include <sys/time.h>
106 
107 #include <net/if.h>
108 #include <net/if_var.h>
109 #include <net/if_types.h>
110 #include <net/raw_cb.h>
111 #include <net/vnet.h>
112 
113 #include <netinet/in.h>
114 #include <netinet/in_var.h>
115 #include <netinet/icmp6.h>
116 #include <netinet/ip_encap.h>
117 
118 #include <netinet/ip6.h>
119 #include <netinet/in_kdtrace.h>
120 #include <netinet6/ip6_var.h>
121 #include <netinet6/scope6_var.h>
122 #include <netinet6/nd6.h>
123 #include <netinet6/ip6_mroute.h>
124 #include <netinet6/ip6protosw.h>
125 #include <netinet6/pim6.h>
126 #include <netinet6/pim6_var.h>
127 
128 static MALLOC_DEFINE(M_MRTABLE6, "mf6c", "multicast forwarding cache entry");
129 
130 /* XXX: this is a very common idiom; move to <sys/mbuf.h> ? */
131 #define M_HASCL(m) ((m)->m_flags & M_EXT)
132 
133 static int	ip6_mdq(struct mbuf *, struct ifnet *, struct mf6c *);
134 static void	phyint_send(struct ip6_hdr *, struct mif6 *, struct mbuf *);
135 static int	register_send(struct ip6_hdr *, struct mif6 *, struct mbuf *);
136 static int	set_pim6(int *);
137 static int	socket_send(struct socket *, struct mbuf *,
138 		    struct sockaddr_in6 *);
139 
140 extern int in6_mcast_loop;
141 extern struct domain inet6domain;
142 
143 static const struct encaptab *pim6_encap_cookie;
144 static const struct ip6protosw in6_pim_protosw = {
145 	.pr_type =		SOCK_RAW,
146 	.pr_domain =		&inet6domain,
147 	.pr_protocol =		IPPROTO_PIM,
148 	.pr_flags =		PR_ATOMIC|PR_ADDR|PR_LASTHDR,
149 	.pr_input =		pim6_input,
150 	.pr_output =		rip6_output,
151 	.pr_ctloutput =		rip6_ctloutput,
152 	.pr_usrreqs =		&rip6_usrreqs
153 };
154 static int pim6_encapcheck(const struct mbuf *, int, int, void *);
155 
156 static VNET_DEFINE(int, ip6_mrouter_ver) = 0;
157 #define	V_ip6_mrouter_ver	VNET(ip6_mrouter_ver)
158 
159 SYSCTL_DECL(_net_inet6);
160 SYSCTL_DECL(_net_inet6_ip6);
161 static SYSCTL_NODE(_net_inet6, IPPROTO_PIM, pim, CTLFLAG_RW, 0, "PIM");
162 
163 static struct mrt6stat mrt6stat;
164 SYSCTL_STRUCT(_net_inet6_ip6, OID_AUTO, mrt6stat, CTLFLAG_RW,
165     &mrt6stat, mrt6stat,
166     "Multicast Routing Statistics (struct mrt6stat, netinet6/ip6_mroute.h)");
167 
168 #define	MRT6STAT_INC(name)	mrt6stat.name += 1
169 #define NO_RTE_FOUND	0x1
170 #define RTE_FOUND	0x2
171 
172 static struct mtx mrouter6_mtx;
173 #define	MROUTER6_LOCK()		mtx_lock(&mrouter6_mtx)
174 #define	MROUTER6_UNLOCK()	mtx_unlock(&mrouter6_mtx)
175 #define	MROUTER6_LOCK_ASSERT()	do {					\
176 	mtx_assert(&mrouter6_mtx, MA_OWNED);				\
177 	NET_ASSERT_GIANT();						\
178 } while (0)
179 #define	MROUTER6_LOCK_INIT()	\
180 	mtx_init(&mrouter6_mtx, "IPv6 multicast forwarding", NULL, MTX_DEF)
181 #define	MROUTER6_LOCK_DESTROY()	mtx_destroy(&mrouter6_mtx)
182 
183 static struct mf6c *mf6ctable[MF6CTBLSIZ];
184 SYSCTL_OPAQUE(_net_inet6_ip6, OID_AUTO, mf6ctable, CTLFLAG_RD,
185     &mf6ctable, sizeof(mf6ctable), "S,*mf6ctable[MF6CTBLSIZ]",
186     "IPv6 Multicast Forwarding Table (struct *mf6ctable[MF6CTBLSIZ], "
187     "netinet6/ip6_mroute.h)");
188 
189 static struct mtx mfc6_mtx;
190 #define	MFC6_LOCK()		mtx_lock(&mfc6_mtx)
191 #define	MFC6_UNLOCK()		mtx_unlock(&mfc6_mtx)
192 #define	MFC6_LOCK_ASSERT()	do {					\
193 	mtx_assert(&mfc6_mtx, MA_OWNED);				\
194 	NET_ASSERT_GIANT();						\
195 } while (0)
196 #define	MFC6_LOCK_INIT()		\
197 	mtx_init(&mfc6_mtx, "IPv6 multicast forwarding cache", NULL, MTX_DEF)
198 #define	MFC6_LOCK_DESTROY()	mtx_destroy(&mfc6_mtx)
199 
200 static u_char n6expire[MF6CTBLSIZ];
201 
202 static struct mif6 mif6table[MAXMIFS];
203 SYSCTL_OPAQUE(_net_inet6_ip6, OID_AUTO, mif6table, CTLFLAG_RD,
204     &mif6table, sizeof(mif6table), "S,mif6[MAXMIFS]",
205     "IPv6 Multicast Interfaces (struct mif6[MAXMIFS], netinet6/ip6_mroute.h)");
206 
207 static struct mtx mif6_mtx;
208 #define	MIF6_LOCK()		mtx_lock(&mif6_mtx)
209 #define	MIF6_UNLOCK()		mtx_unlock(&mif6_mtx)
210 #define	MIF6_LOCK_ASSERT()	mtx_assert(&mif6_mtx, MA_OWNED)
211 #define	MIF6_LOCK_INIT()	\
212 	mtx_init(&mif6_mtx, "IPv6 multicast interfaces", NULL, MTX_DEF)
213 #define	MIF6_LOCK_DESTROY()	mtx_destroy(&mif6_mtx)
214 
215 #ifdef MRT6DEBUG
216 static VNET_DEFINE(u_int, mrt6debug) = 0;	/* debug level */
217 #define	V_mrt6debug		VNET(mrt6debug)
218 #define DEBUG_MFC	0x02
219 #define DEBUG_FORWARD	0x04
220 #define DEBUG_EXPIRE	0x08
221 #define DEBUG_XMIT	0x10
222 #define DEBUG_REG	0x20
223 #define DEBUG_PIM	0x40
224 #endif
225 
226 static void	expire_upcalls(void *);
227 #define	EXPIRE_TIMEOUT	(hz / 4)	/* 4x / second */
228 #define	UPCALL_EXPIRE	6		/* number of timeouts */
229 
230 /*
231  * XXX TODO: maintain a count to if_allmulti() calls in struct ifnet.
232  */
233 
234 /*
235  * 'Interfaces' associated with decapsulator (so we can tell
236  * packets that went through it from ones that get reflected
237  * by a broken gateway).  Different from IPv4 register_if,
238  * these interfaces are linked into the system ifnet list,
239  * because per-interface IPv6 statistics are maintained in
240  * ifp->if_afdata.  But it does not have any routes point
241  * to them.  I.e., packets can't be sent this way.  They
242  * only exist as a placeholder for multicast source
243  * verification.
244  */
245 static struct ifnet *multicast_register_if6;
246 
247 #define ENCAP_HOPS 64
248 
249 /*
250  * Private variables.
251  */
252 static mifi_t nummifs = 0;
253 static mifi_t reg_mif_num = (mifi_t)-1;
254 
255 static struct pim6stat pim6stat;
256 SYSCTL_STRUCT(_net_inet6_pim, PIM6CTL_STATS, stats, CTLFLAG_RW,
257     &pim6stat, pim6stat,
258     "PIM Statistics (struct pim6stat, netinet6/pim6_var.h)");
259 
260 #define	PIM6STAT_INC(name)	pim6stat.name += 1
261 static VNET_DEFINE(int, pim6);
262 #define	V_pim6		VNET(pim6)
263 
264 /*
265  * Hash function for a source, group entry
266  */
267 #define MF6CHASH(a, g) MF6CHASHMOD((a).s6_addr32[0] ^ (a).s6_addr32[1] ^ \
268 				   (a).s6_addr32[2] ^ (a).s6_addr32[3] ^ \
269 				   (g).s6_addr32[0] ^ (g).s6_addr32[1] ^ \
270 				   (g).s6_addr32[2] ^ (g).s6_addr32[3])
271 
272 /*
273  * Find a route for a given origin IPv6 address and Multicast group address.
274  */
275 #define MF6CFIND(o, g, rt) do { \
276 	struct mf6c *_rt = mf6ctable[MF6CHASH(o,g)]; \
277 	rt = NULL; \
278 	MRT6STAT_INC(mrt6s_mfc_lookups); \
279 	while (_rt) { \
280 		if (IN6_ARE_ADDR_EQUAL(&_rt->mf6c_origin.sin6_addr, &(o)) && \
281 		    IN6_ARE_ADDR_EQUAL(&_rt->mf6c_mcastgrp.sin6_addr, &(g)) && \
282 		    (_rt->mf6c_stall == NULL)) { \
283 			rt = _rt; \
284 			break; \
285 		} \
286 		_rt = _rt->mf6c_next; \
287 	} \
288 	if (rt == NULL) { \
289 		MRT6STAT_INC(mrt6s_mfc_misses); \
290 	} \
291 } while (/*CONSTCOND*/ 0)
292 
293 /*
294  * Macros to compute elapsed time efficiently
295  * Borrowed from Van Jacobson's scheduling code
296  * XXX: replace with timersub() ?
297  */
298 #define TV_DELTA(a, b, delta) do { \
299 	    int xxs; \
300 		\
301 	    delta = (a).tv_usec - (b).tv_usec; \
302 	    if ((xxs = (a).tv_sec - (b).tv_sec)) { \
303 	       switch (xxs) { \
304 		      case 2: \
305 			  delta += 1000000; \
306 			      /* FALLTHROUGH */ \
307 		      case 1: \
308 			  delta += 1000000; \
309 			  break; \
310 		      default: \
311 			  delta += (1000000 * xxs); \
312 	       } \
313 	    } \
314 } while (/*CONSTCOND*/ 0)
315 
316 /* XXX: replace with timercmp(a, b, <) ? */
317 #define TV_LT(a, b) (((a).tv_usec < (b).tv_usec && \
318 	      (a).tv_sec <= (b).tv_sec) || (a).tv_sec < (b).tv_sec)
319 
320 #ifdef UPCALL_TIMING
321 #define UPCALL_MAX	50
322 static u_long upcall_data[UPCALL_MAX + 1];
323 static void collate();
324 #endif /* UPCALL_TIMING */
325 
326 static int ip6_mrouter_init(struct socket *, int, int);
327 static int add_m6fc(struct mf6cctl *);
328 static int add_m6if(struct mif6ctl *);
329 static int del_m6fc(struct mf6cctl *);
330 static int del_m6if(mifi_t *);
331 static int del_m6if_locked(mifi_t *);
332 static int get_mif6_cnt(struct sioc_mif_req6 *);
333 static int get_sg_cnt(struct sioc_sg_req6 *);
334 
335 static struct callout expire_upcalls_ch;
336 
337 int X_ip6_mforward(struct ip6_hdr *, struct ifnet *, struct mbuf *);
338 int X_ip6_mrouter_done(void);
339 int X_ip6_mrouter_set(struct socket *, struct sockopt *);
340 int X_ip6_mrouter_get(struct socket *, struct sockopt *);
341 int X_mrt6_ioctl(u_long, caddr_t);
342 
343 /*
344  * Handle MRT setsockopt commands to modify the multicast routing tables.
345  */
346 int
347 X_ip6_mrouter_set(struct socket *so, struct sockopt *sopt)
348 {
349 	int error = 0;
350 	int optval;
351 	struct mif6ctl mifc;
352 	struct mf6cctl mfcc;
353 	mifi_t mifi;
354 
355 	if (so != V_ip6_mrouter && sopt->sopt_name != MRT6_INIT)
356 		return (EACCES);
357 
358 	switch (sopt->sopt_name) {
359 	case MRT6_INIT:
360 #ifdef MRT6_OINIT
361 	case MRT6_OINIT:
362 #endif
363 		error = sooptcopyin(sopt, &optval, sizeof(optval),
364 		    sizeof(optval));
365 		if (error)
366 			break;
367 		error = ip6_mrouter_init(so, optval, sopt->sopt_name);
368 		break;
369 	case MRT6_DONE:
370 		error = X_ip6_mrouter_done();
371 		break;
372 	case MRT6_ADD_MIF:
373 		error = sooptcopyin(sopt, &mifc, sizeof(mifc), sizeof(mifc));
374 		if (error)
375 			break;
376 		error = add_m6if(&mifc);
377 		break;
378 	case MRT6_ADD_MFC:
379 		error = sooptcopyin(sopt, &mfcc, sizeof(mfcc), sizeof(mfcc));
380 		if (error)
381 			break;
382 		error = add_m6fc(&mfcc);
383 		break;
384 	case MRT6_DEL_MFC:
385 		error = sooptcopyin(sopt, &mfcc, sizeof(mfcc), sizeof(mfcc));
386 		if (error)
387 			break;
388 		error = del_m6fc(&mfcc);
389 		break;
390 	case MRT6_DEL_MIF:
391 		error = sooptcopyin(sopt, &mifi, sizeof(mifi), sizeof(mifi));
392 		if (error)
393 			break;
394 		error = del_m6if(&mifi);
395 		break;
396 	case MRT6_PIM:
397 		error = sooptcopyin(sopt, &optval, sizeof(optval),
398 		    sizeof(optval));
399 		if (error)
400 			break;
401 		error = set_pim6(&optval);
402 		break;
403 	default:
404 		error = EOPNOTSUPP;
405 		break;
406 	}
407 
408 	return (error);
409 }
410 
411 /*
412  * Handle MRT getsockopt commands
413  */
414 int
415 X_ip6_mrouter_get(struct socket *so, struct sockopt *sopt)
416 {
417 	int error = 0;
418 
419 	if (so != V_ip6_mrouter)
420 		return (EACCES);
421 
422 	switch (sopt->sopt_name) {
423 		case MRT6_PIM:
424 			error = sooptcopyout(sopt, &V_pim6, sizeof(V_pim6));
425 			break;
426 	}
427 	return (error);
428 }
429 
430 /*
431  * Handle ioctl commands to obtain information from the cache
432  */
433 int
434 X_mrt6_ioctl(u_long cmd, caddr_t data)
435 {
436 	int ret;
437 
438 	ret = EINVAL;
439 
440 	switch (cmd) {
441 	case SIOCGETSGCNT_IN6:
442 		ret = get_sg_cnt((struct sioc_sg_req6 *)data);
443 		break;
444 
445 	case SIOCGETMIFCNT_IN6:
446 		ret = get_mif6_cnt((struct sioc_mif_req6 *)data);
447 		break;
448 
449 	default:
450 		break;
451 	}
452 
453 	return (ret);
454 }
455 
456 /*
457  * returns the packet, byte, rpf-failure count for the source group provided
458  */
459 static int
460 get_sg_cnt(struct sioc_sg_req6 *req)
461 {
462 	struct mf6c *rt;
463 	int ret;
464 
465 	ret = 0;
466 
467 	MFC6_LOCK();
468 
469 	MF6CFIND(req->src.sin6_addr, req->grp.sin6_addr, rt);
470 	if (rt == NULL) {
471 		ret = ESRCH;
472 	} else {
473 		req->pktcnt = rt->mf6c_pkt_cnt;
474 		req->bytecnt = rt->mf6c_byte_cnt;
475 		req->wrong_if = rt->mf6c_wrong_if;
476 	}
477 
478 	MFC6_UNLOCK();
479 
480 	return (ret);
481 }
482 
483 /*
484  * returns the input and output packet and byte counts on the mif provided
485  */
486 static int
487 get_mif6_cnt(struct sioc_mif_req6 *req)
488 {
489 	mifi_t mifi;
490 	int ret;
491 
492 	ret = 0;
493 	mifi = req->mifi;
494 
495 	MIF6_LOCK();
496 
497 	if (mifi >= nummifs) {
498 		ret = EINVAL;
499 	} else {
500 		req->icount = mif6table[mifi].m6_pkt_in;
501 		req->ocount = mif6table[mifi].m6_pkt_out;
502 		req->ibytes = mif6table[mifi].m6_bytes_in;
503 		req->obytes = mif6table[mifi].m6_bytes_out;
504 	}
505 
506 	MIF6_UNLOCK();
507 
508 	return (ret);
509 }
510 
511 static int
512 set_pim6(int *i)
513 {
514 	if ((*i != 1) && (*i != 0))
515 		return (EINVAL);
516 
517 	V_pim6 = *i;
518 
519 	return (0);
520 }
521 
522 /*
523  * Enable multicast routing
524  */
525 static int
526 ip6_mrouter_init(struct socket *so, int v, int cmd)
527 {
528 
529 #ifdef MRT6DEBUG
530 	if (V_mrt6debug)
531 		log(LOG_DEBUG,
532 		    "ip6_mrouter_init: so_type = %d, pr_protocol = %d\n",
533 		    so->so_type, so->so_proto->pr_protocol);
534 #endif
535 
536 	if (so->so_type != SOCK_RAW ||
537 	    so->so_proto->pr_protocol != IPPROTO_ICMPV6)
538 		return (EOPNOTSUPP);
539 
540 	if (v != 1)
541 		return (ENOPROTOOPT);
542 
543 	MROUTER6_LOCK();
544 
545 	if (V_ip6_mrouter != NULL) {
546 		MROUTER6_UNLOCK();
547 		return (EADDRINUSE);
548 	}
549 
550 	V_ip6_mrouter = so;
551 	V_ip6_mrouter_ver = cmd;
552 
553 	bzero((caddr_t)mf6ctable, sizeof(mf6ctable));
554 	bzero((caddr_t)n6expire, sizeof(n6expire));
555 
556 	V_pim6 = 0;/* used for stubbing out/in pim stuff */
557 
558 	callout_init(&expire_upcalls_ch, 0);
559 	callout_reset(&expire_upcalls_ch, EXPIRE_TIMEOUT,
560 	    expire_upcalls, NULL);
561 
562 	MROUTER6_UNLOCK();
563 
564 #ifdef MRT6DEBUG
565 	if (V_mrt6debug)
566 		log(LOG_DEBUG, "ip6_mrouter_init\n");
567 #endif
568 
569 	return (0);
570 }
571 
572 /*
573  * Disable IPv6 multicast forwarding.
574  */
575 int
576 X_ip6_mrouter_done(void)
577 {
578 	mifi_t mifi;
579 	u_long i;
580 	struct mf6c *rt;
581 	struct rtdetq *rte;
582 
583 	MROUTER6_LOCK();
584 
585 	if (V_ip6_mrouter == NULL) {
586 		MROUTER6_UNLOCK();
587 		return (EINVAL);
588 	}
589 
590 	/*
591 	 * For each phyint in use, disable promiscuous reception of all IPv6
592 	 * multicasts.
593 	 */
594 	for (mifi = 0; mifi < nummifs; mifi++) {
595 		if (mif6table[mifi].m6_ifp &&
596 		    !(mif6table[mifi].m6_flags & MIFF_REGISTER)) {
597 			if_allmulti(mif6table[mifi].m6_ifp, 0);
598 		}
599 	}
600 	bzero((caddr_t)mif6table, sizeof(mif6table));
601 	nummifs = 0;
602 
603 	V_pim6 = 0; /* used to stub out/in pim specific code */
604 
605 	callout_stop(&expire_upcalls_ch);
606 
607 	/*
608 	 * Free all multicast forwarding cache entries.
609 	 */
610 	MFC6_LOCK();
611 	for (i = 0; i < MF6CTBLSIZ; i++) {
612 		rt = mf6ctable[i];
613 		while (rt) {
614 			struct mf6c *frt;
615 
616 			for (rte = rt->mf6c_stall; rte != NULL; ) {
617 				struct rtdetq *n = rte->next;
618 
619 				m_freem(rte->m);
620 				free(rte, M_MRTABLE6);
621 				rte = n;
622 			}
623 			frt = rt;
624 			rt = rt->mf6c_next;
625 			free(frt, M_MRTABLE6);
626 		}
627 	}
628 	bzero((caddr_t)mf6ctable, sizeof(mf6ctable));
629 	MFC6_UNLOCK();
630 
631 	/*
632 	 * Reset register interface
633 	 */
634 	if (reg_mif_num != (mifi_t)-1 && multicast_register_if6 != NULL) {
635 		if_detach(multicast_register_if6);
636 		if_free(multicast_register_if6);
637 		reg_mif_num = (mifi_t)-1;
638 		multicast_register_if6 = NULL;
639 	}
640 
641 	V_ip6_mrouter = NULL;
642 	V_ip6_mrouter_ver = 0;
643 
644 	MROUTER6_UNLOCK();
645 
646 #ifdef MRT6DEBUG
647 	if (V_mrt6debug)
648 		log(LOG_DEBUG, "ip6_mrouter_done\n");
649 #endif
650 
651 	return (0);
652 }
653 
654 static struct sockaddr_in6 sin6 = { sizeof(sin6), AF_INET6 };
655 
656 /*
657  * Add a mif to the mif table
658  */
659 static int
660 add_m6if(struct mif6ctl *mifcp)
661 {
662 	struct mif6 *mifp;
663 	struct ifnet *ifp;
664 	int error;
665 
666 	MIF6_LOCK();
667 
668 	if (mifcp->mif6c_mifi >= MAXMIFS) {
669 		MIF6_UNLOCK();
670 		return (EINVAL);
671 	}
672 	mifp = mif6table + mifcp->mif6c_mifi;
673 	if (mifp->m6_ifp != NULL) {
674 		MIF6_UNLOCK();
675 		return (EADDRINUSE); /* XXX: is it appropriate? */
676 	}
677 	if (mifcp->mif6c_pifi == 0 || mifcp->mif6c_pifi > V_if_index) {
678 		MIF6_UNLOCK();
679 		return (ENXIO);
680 	}
681 
682 	ifp = ifnet_byindex(mifcp->mif6c_pifi);
683 
684 	if (mifcp->mif6c_flags & MIFF_REGISTER) {
685 		if (reg_mif_num == (mifi_t)-1) {
686 			ifp = if_alloc(IFT_OTHER);
687 
688 			if_initname(ifp, "register_mif", 0);
689 			ifp->if_flags |= IFF_LOOPBACK;
690 			if_attach(ifp);
691 			multicast_register_if6 = ifp;
692 			reg_mif_num = mifcp->mif6c_mifi;
693 			/*
694 			 * it is impossible to guess the ifindex of the
695 			 * register interface.  So mif6c_pifi is automatically
696 			 * calculated.
697 			 */
698 			mifcp->mif6c_pifi = ifp->if_index;
699 		} else {
700 			ifp = multicast_register_if6;
701 		}
702 	} else {
703 		/* Make sure the interface supports multicast */
704 		if ((ifp->if_flags & IFF_MULTICAST) == 0) {
705 			MIF6_UNLOCK();
706 			return (EOPNOTSUPP);
707 		}
708 
709 		error = if_allmulti(ifp, 1);
710 		if (error) {
711 			MIF6_UNLOCK();
712 			return (error);
713 		}
714 	}
715 
716 	mifp->m6_flags     = mifcp->mif6c_flags;
717 	mifp->m6_ifp       = ifp;
718 
719 	/* initialize per mif pkt counters */
720 	mifp->m6_pkt_in    = 0;
721 	mifp->m6_pkt_out   = 0;
722 	mifp->m6_bytes_in  = 0;
723 	mifp->m6_bytes_out = 0;
724 
725 	/* Adjust nummifs up if the mifi is higher than nummifs */
726 	if (nummifs <= mifcp->mif6c_mifi)
727 		nummifs = mifcp->mif6c_mifi + 1;
728 
729 	MIF6_UNLOCK();
730 
731 #ifdef MRT6DEBUG
732 	if (V_mrt6debug)
733 		log(LOG_DEBUG,
734 		    "add_mif #%d, phyint %s\n",
735 		    mifcp->mif6c_mifi,
736 		    ifp->if_xname);
737 #endif
738 
739 	return (0);
740 }
741 
742 /*
743  * Delete a mif from the mif table
744  */
745 static int
746 del_m6if_locked(mifi_t *mifip)
747 {
748 	struct mif6 *mifp = mif6table + *mifip;
749 	mifi_t mifi;
750 	struct ifnet *ifp;
751 
752 	MIF6_LOCK_ASSERT();
753 
754 	if (*mifip >= nummifs)
755 		return (EINVAL);
756 	if (mifp->m6_ifp == NULL)
757 		return (EINVAL);
758 
759 	if (!(mifp->m6_flags & MIFF_REGISTER)) {
760 		/* XXX: TODO: Maintain an ALLMULTI refcount in struct ifnet. */
761 		ifp = mifp->m6_ifp;
762 		if_allmulti(ifp, 0);
763 	} else {
764 		if (reg_mif_num != (mifi_t)-1 &&
765 		    multicast_register_if6 != NULL) {
766 			if_detach(multicast_register_if6);
767 			if_free(multicast_register_if6);
768 			reg_mif_num = (mifi_t)-1;
769 			multicast_register_if6 = NULL;
770 		}
771 	}
772 
773 	bzero((caddr_t)mifp, sizeof(*mifp));
774 
775 	/* Adjust nummifs down */
776 	for (mifi = nummifs; mifi > 0; mifi--)
777 		if (mif6table[mifi - 1].m6_ifp)
778 			break;
779 	nummifs = mifi;
780 
781 #ifdef MRT6DEBUG
782 	if (V_mrt6debug)
783 		log(LOG_DEBUG, "del_m6if %d, nummifs %d\n", *mifip, nummifs);
784 #endif
785 
786 	return (0);
787 }
788 
789 static int
790 del_m6if(mifi_t *mifip)
791 {
792 	int cc;
793 
794 	MIF6_LOCK();
795 	cc = del_m6if_locked(mifip);
796 	MIF6_UNLOCK();
797 
798 	return (cc);
799 }
800 
801 /*
802  * Add an mfc entry
803  */
804 static int
805 add_m6fc(struct mf6cctl *mfccp)
806 {
807 	struct mf6c *rt;
808 	u_long hash;
809 	struct rtdetq *rte;
810 	u_short nstl;
811 	char ip6bufo[INET6_ADDRSTRLEN], ip6bufg[INET6_ADDRSTRLEN];
812 
813 	MFC6_LOCK();
814 
815 	MF6CFIND(mfccp->mf6cc_origin.sin6_addr,
816 		 mfccp->mf6cc_mcastgrp.sin6_addr, rt);
817 
818 	/* If an entry already exists, just update the fields */
819 	if (rt) {
820 #ifdef MRT6DEBUG
821 		if (V_mrt6debug & DEBUG_MFC) {
822 		    log(LOG_DEBUG,
823 			"add_m6fc no upcall h %d o %s g %s p %x\n",
824 			ip6_sprintf(ip6bufo, &mfccp->mf6cc_origin.sin6_addr),
825 			ip6_sprintf(ip6bufg, &mfccp->mf6cc_mcastgrp.sin6_addr),
826 			mfccp->mf6cc_parent);
827 		}
828 #endif
829 
830 		rt->mf6c_parent = mfccp->mf6cc_parent;
831 		rt->mf6c_ifset = mfccp->mf6cc_ifset;
832 
833 		MFC6_UNLOCK();
834 		return (0);
835 	}
836 
837 	/*
838 	 * Find the entry for which the upcall was made and update
839 	 */
840 	hash = MF6CHASH(mfccp->mf6cc_origin.sin6_addr,
841 			mfccp->mf6cc_mcastgrp.sin6_addr);
842 	for (rt = mf6ctable[hash], nstl = 0; rt; rt = rt->mf6c_next) {
843 		if (IN6_ARE_ADDR_EQUAL(&rt->mf6c_origin.sin6_addr,
844 				       &mfccp->mf6cc_origin.sin6_addr) &&
845 		    IN6_ARE_ADDR_EQUAL(&rt->mf6c_mcastgrp.sin6_addr,
846 				       &mfccp->mf6cc_mcastgrp.sin6_addr) &&
847 		    (rt->mf6c_stall != NULL)) {
848 
849 			if (nstl++)
850 				log(LOG_ERR,
851 				    "add_m6fc: %s o %s g %s p %x dbx %p\n",
852 				    "multiple kernel entries",
853 				    ip6_sprintf(ip6bufo,
854 					    &mfccp->mf6cc_origin.sin6_addr),
855 				    ip6_sprintf(ip6bufg,
856 					    &mfccp->mf6cc_mcastgrp.sin6_addr),
857 				    mfccp->mf6cc_parent, rt->mf6c_stall);
858 
859 #ifdef MRT6DEBUG
860 			if (V_mrt6debug & DEBUG_MFC)
861 				log(LOG_DEBUG,
862 				    "add_m6fc o %s g %s p %x dbg %x\n",
863 				    ip6_sprintf(ip6bufo,
864 					    &mfccp->mf6cc_origin.sin6_addr),
865 				    ip6_sprintf(ip6bufg,
866 					    &mfccp->mf6cc_mcastgrp.sin6_addr),
867 				    mfccp->mf6cc_parent, rt->mf6c_stall);
868 #endif
869 
870 			rt->mf6c_origin     = mfccp->mf6cc_origin;
871 			rt->mf6c_mcastgrp   = mfccp->mf6cc_mcastgrp;
872 			rt->mf6c_parent     = mfccp->mf6cc_parent;
873 			rt->mf6c_ifset	    = mfccp->mf6cc_ifset;
874 			/* initialize pkt counters per src-grp */
875 			rt->mf6c_pkt_cnt    = 0;
876 			rt->mf6c_byte_cnt   = 0;
877 			rt->mf6c_wrong_if   = 0;
878 
879 			rt->mf6c_expire = 0;	/* Don't clean this guy up */
880 			n6expire[hash]--;
881 
882 			/* free packets Qed at the end of this entry */
883 			for (rte = rt->mf6c_stall; rte != NULL; ) {
884 				struct rtdetq *n = rte->next;
885 				ip6_mdq(rte->m, rte->ifp, rt);
886 				m_freem(rte->m);
887 #ifdef UPCALL_TIMING
888 				collate(&(rte->t));
889 #endif /* UPCALL_TIMING */
890 				free(rte, M_MRTABLE6);
891 				rte = n;
892 			}
893 			rt->mf6c_stall = NULL;
894 		}
895 	}
896 
897 	/*
898 	 * It is possible that an entry is being inserted without an upcall
899 	 */
900 	if (nstl == 0) {
901 #ifdef MRT6DEBUG
902 		if (V_mrt6debug & DEBUG_MFC)
903 		    log(LOG_DEBUG,
904 			"add_mfc no upcall h %d o %s g %s p %x\n",
905 			hash,
906 			ip6_sprintf(ip6bufo, &mfccp->mf6cc_origin.sin6_addr),
907 			ip6_sprintf(ip6bufg, &mfccp->mf6cc_mcastgrp.sin6_addr),
908 			mfccp->mf6cc_parent);
909 #endif
910 
911 		for (rt = mf6ctable[hash]; rt; rt = rt->mf6c_next) {
912 
913 			if (IN6_ARE_ADDR_EQUAL(&rt->mf6c_origin.sin6_addr,
914 					       &mfccp->mf6cc_origin.sin6_addr)&&
915 			    IN6_ARE_ADDR_EQUAL(&rt->mf6c_mcastgrp.sin6_addr,
916 					       &mfccp->mf6cc_mcastgrp.sin6_addr)) {
917 
918 				rt->mf6c_origin     = mfccp->mf6cc_origin;
919 				rt->mf6c_mcastgrp   = mfccp->mf6cc_mcastgrp;
920 				rt->mf6c_parent     = mfccp->mf6cc_parent;
921 				rt->mf6c_ifset	    = mfccp->mf6cc_ifset;
922 				/* initialize pkt counters per src-grp */
923 				rt->mf6c_pkt_cnt    = 0;
924 				rt->mf6c_byte_cnt   = 0;
925 				rt->mf6c_wrong_if   = 0;
926 
927 				if (rt->mf6c_expire)
928 					n6expire[hash]--;
929 				rt->mf6c_expire	   = 0;
930 			}
931 		}
932 		if (rt == NULL) {
933 			/* no upcall, so make a new entry */
934 			rt = (struct mf6c *)malloc(sizeof(*rt), M_MRTABLE6,
935 						  M_NOWAIT);
936 			if (rt == NULL) {
937 				MFC6_UNLOCK();
938 				return (ENOBUFS);
939 			}
940 
941 			/* insert new entry at head of hash chain */
942 			rt->mf6c_origin     = mfccp->mf6cc_origin;
943 			rt->mf6c_mcastgrp   = mfccp->mf6cc_mcastgrp;
944 			rt->mf6c_parent     = mfccp->mf6cc_parent;
945 			rt->mf6c_ifset	    = mfccp->mf6cc_ifset;
946 			/* initialize pkt counters per src-grp */
947 			rt->mf6c_pkt_cnt    = 0;
948 			rt->mf6c_byte_cnt   = 0;
949 			rt->mf6c_wrong_if   = 0;
950 			rt->mf6c_expire     = 0;
951 			rt->mf6c_stall = NULL;
952 
953 			/* link into table */
954 			rt->mf6c_next  = mf6ctable[hash];
955 			mf6ctable[hash] = rt;
956 		}
957 	}
958 
959 	MFC6_UNLOCK();
960 	return (0);
961 }
962 
963 #ifdef UPCALL_TIMING
964 /*
965  * collect delay statistics on the upcalls
966  */
967 static void
968 collate(struct timeval *t)
969 {
970 	u_long d;
971 	struct timeval tp;
972 	u_long delta;
973 
974 	GET_TIME(tp);
975 
976 	if (TV_LT(*t, tp))
977 	{
978 		TV_DELTA(tp, *t, delta);
979 
980 		d = delta >> 10;
981 		if (d > UPCALL_MAX)
982 			d = UPCALL_MAX;
983 
984 		++upcall_data[d];
985 	}
986 }
987 #endif /* UPCALL_TIMING */
988 
989 /*
990  * Delete an mfc entry
991  */
992 static int
993 del_m6fc(struct mf6cctl *mfccp)
994 {
995 	struct sockaddr_in6	origin;
996 	struct sockaddr_in6	mcastgrp;
997 	struct mf6c		*rt;
998 	struct mf6c		**nptr;
999 	u_long		hash;
1000 
1001 	origin = mfccp->mf6cc_origin;
1002 	mcastgrp = mfccp->mf6cc_mcastgrp;
1003 	hash = MF6CHASH(origin.sin6_addr, mcastgrp.sin6_addr);
1004 
1005 #ifdef MRT6DEBUG
1006 	if (V_mrt6debug & DEBUG_MFC) {
1007 		char ip6bufo[INET6_ADDRSTRLEN], ip6bufg[INET6_ADDRSTRLEN];
1008 		log(LOG_DEBUG,"del_m6fc orig %s mcastgrp %s\n",
1009 		    ip6_sprintf(ip6bufo, &origin.sin6_addr),
1010 		    ip6_sprintf(ip6bufg, &mcastgrp.sin6_addr));
1011 	}
1012 #endif
1013 
1014 	MFC6_LOCK();
1015 
1016 	nptr = &mf6ctable[hash];
1017 	while ((rt = *nptr) != NULL) {
1018 		if (IN6_ARE_ADDR_EQUAL(&origin.sin6_addr,
1019 				       &rt->mf6c_origin.sin6_addr) &&
1020 		    IN6_ARE_ADDR_EQUAL(&mcastgrp.sin6_addr,
1021 				       &rt->mf6c_mcastgrp.sin6_addr) &&
1022 		    rt->mf6c_stall == NULL)
1023 			break;
1024 
1025 		nptr = &rt->mf6c_next;
1026 	}
1027 	if (rt == NULL) {
1028 		MFC6_UNLOCK();
1029 		return (EADDRNOTAVAIL);
1030 	}
1031 
1032 	*nptr = rt->mf6c_next;
1033 	free(rt, M_MRTABLE6);
1034 
1035 	MFC6_UNLOCK();
1036 
1037 	return (0);
1038 }
1039 
1040 static int
1041 socket_send(struct socket *s, struct mbuf *mm, struct sockaddr_in6 *src)
1042 {
1043 
1044 	if (s) {
1045 		if (sbappendaddr(&s->so_rcv,
1046 				 (struct sockaddr *)src,
1047 				 mm, (struct mbuf *)0) != 0) {
1048 			sorwakeup(s);
1049 			return (0);
1050 		}
1051 	}
1052 	m_freem(mm);
1053 	return (-1);
1054 }
1055 
1056 /*
1057  * IPv6 multicast forwarding function. This function assumes that the packet
1058  * pointed to by "ip6" has arrived on (or is about to be sent to) the interface
1059  * pointed to by "ifp", and the packet is to be relayed to other networks
1060  * that have members of the packet's destination IPv6 multicast group.
1061  *
1062  * The packet is returned unscathed to the caller, unless it is
1063  * erroneous, in which case a non-zero return value tells the caller to
1064  * discard it.
1065  *
1066  * NOTE: this implementation assumes that m->m_pkthdr.rcvif is NULL iff
1067  * this function is called in the originating context (i.e., not when
1068  * forwarding a packet from other node).  ip6_output(), which is currently the
1069  * only function that calls this function is called in the originating context,
1070  * explicitly ensures this condition.  It is caller's responsibility to ensure
1071  * that if this function is called from somewhere else in the originating
1072  * context in the future.
1073  */
1074 int
1075 X_ip6_mforward(struct ip6_hdr *ip6, struct ifnet *ifp, struct mbuf *m)
1076 {
1077 	struct mf6c *rt;
1078 	struct mif6 *mifp;
1079 	struct mbuf *mm;
1080 	mifi_t mifi;
1081 	char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
1082 
1083 #ifdef MRT6DEBUG
1084 	if (V_mrt6debug & DEBUG_FORWARD)
1085 		log(LOG_DEBUG, "ip6_mforward: src %s, dst %s, ifindex %d\n",
1086 		    ip6_sprintf(ip6bufs, &ip6->ip6_src),
1087 		    ip6_sprintf(ip6bufd, &ip6->ip6_dst),
1088 		    ifp->if_index);
1089 #endif
1090 
1091 	/*
1092 	 * Don't forward a packet with Hop limit of zero or one,
1093 	 * or a packet destined to a local-only group.
1094 	 */
1095 	if (ip6->ip6_hlim <= 1 || IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst) ||
1096 	    IN6_IS_ADDR_MC_LINKLOCAL(&ip6->ip6_dst))
1097 		return (0);
1098 	ip6->ip6_hlim--;
1099 
1100 	/*
1101 	 * Source address check: do not forward packets with unspecified
1102 	 * source. It was discussed in July 2000, on ipngwg mailing list.
1103 	 * This is rather more serious than unicast cases, because some
1104 	 * MLD packets can be sent with the unspecified source address
1105 	 * (although such packets must normally set 1 to the hop limit field).
1106 	 */
1107 	if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src)) {
1108 		IP6STAT_INC(ip6s_cantforward);
1109 		if (V_ip6_log_time + V_ip6_log_interval < time_uptime) {
1110 			V_ip6_log_time = time_uptime;
1111 			log(LOG_DEBUG,
1112 			    "cannot forward "
1113 			    "from %s to %s nxt %d received on %s\n",
1114 			    ip6_sprintf(ip6bufs, &ip6->ip6_src),
1115 			    ip6_sprintf(ip6bufd, &ip6->ip6_dst),
1116 			    ip6->ip6_nxt,
1117 			    if_name(m->m_pkthdr.rcvif));
1118 		}
1119 		return (0);
1120 	}
1121 
1122 	MFC6_LOCK();
1123 
1124 	/*
1125 	 * Determine forwarding mifs from the forwarding cache table
1126 	 */
1127 	MF6CFIND(ip6->ip6_src, ip6->ip6_dst, rt);
1128 
1129 	/* Entry exists, so forward if necessary */
1130 	if (rt) {
1131 		MFC6_UNLOCK();
1132 		return (ip6_mdq(m, ifp, rt));
1133 	} else {
1134 		/*
1135 		 * If we don't have a route for packet's origin,
1136 		 * Make a copy of the packet &
1137 		 * send message to routing daemon
1138 		 */
1139 
1140 		struct mbuf *mb0;
1141 		struct rtdetq *rte;
1142 		u_long hash;
1143 /*		int i, npkts;*/
1144 #ifdef UPCALL_TIMING
1145 		struct timeval tp;
1146 
1147 		GET_TIME(tp);
1148 #endif /* UPCALL_TIMING */
1149 
1150 		MRT6STAT_INC(mrt6s_no_route);
1151 #ifdef MRT6DEBUG
1152 		if (V_mrt6debug & (DEBUG_FORWARD | DEBUG_MFC))
1153 			log(LOG_DEBUG, "ip6_mforward: no rte s %s g %s\n",
1154 			    ip6_sprintf(ip6bufs, &ip6->ip6_src),
1155 			    ip6_sprintf(ip6bufd, &ip6->ip6_dst));
1156 #endif
1157 
1158 		/*
1159 		 * Allocate mbufs early so that we don't do extra work if we
1160 		 * are just going to fail anyway.
1161 		 */
1162 		rte = (struct rtdetq *)malloc(sizeof(*rte), M_MRTABLE6,
1163 					      M_NOWAIT);
1164 		if (rte == NULL) {
1165 			MFC6_UNLOCK();
1166 			return (ENOBUFS);
1167 		}
1168 		mb0 = m_copy(m, 0, M_COPYALL);
1169 		/*
1170 		 * Pullup packet header if needed before storing it,
1171 		 * as other references may modify it in the meantime.
1172 		 */
1173 		if (mb0 &&
1174 		    (M_HASCL(mb0) || mb0->m_len < sizeof(struct ip6_hdr)))
1175 			mb0 = m_pullup(mb0, sizeof(struct ip6_hdr));
1176 		if (mb0 == NULL) {
1177 			free(rte, M_MRTABLE6);
1178 			MFC6_UNLOCK();
1179 			return (ENOBUFS);
1180 		}
1181 
1182 		/* is there an upcall waiting for this packet? */
1183 		hash = MF6CHASH(ip6->ip6_src, ip6->ip6_dst);
1184 		for (rt = mf6ctable[hash]; rt; rt = rt->mf6c_next) {
1185 			if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_src,
1186 					       &rt->mf6c_origin.sin6_addr) &&
1187 			    IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst,
1188 					       &rt->mf6c_mcastgrp.sin6_addr) &&
1189 			    (rt->mf6c_stall != NULL))
1190 				break;
1191 		}
1192 
1193 		if (rt == NULL) {
1194 			struct mrt6msg *im;
1195 #ifdef MRT6_OINIT
1196 			struct omrt6msg *oim;
1197 #endif
1198 
1199 			/* no upcall, so make a new entry */
1200 			rt = (struct mf6c *)malloc(sizeof(*rt), M_MRTABLE6,
1201 						  M_NOWAIT);
1202 			if (rt == NULL) {
1203 				free(rte, M_MRTABLE6);
1204 				m_freem(mb0);
1205 				MFC6_UNLOCK();
1206 				return (ENOBUFS);
1207 			}
1208 			/*
1209 			 * Make a copy of the header to send to the user
1210 			 * level process
1211 			 */
1212 			mm = m_copy(mb0, 0, sizeof(struct ip6_hdr));
1213 
1214 			if (mm == NULL) {
1215 				free(rte, M_MRTABLE6);
1216 				m_freem(mb0);
1217 				free(rt, M_MRTABLE6);
1218 				MFC6_UNLOCK();
1219 				return (ENOBUFS);
1220 			}
1221 
1222 			/*
1223 			 * Send message to routing daemon
1224 			 */
1225 			sin6.sin6_addr = ip6->ip6_src;
1226 
1227 			im = NULL;
1228 #ifdef MRT6_OINIT
1229 			oim = NULL;
1230 #endif
1231 			switch (V_ip6_mrouter_ver) {
1232 #ifdef MRT6_OINIT
1233 			case MRT6_OINIT:
1234 				oim = mtod(mm, struct omrt6msg *);
1235 				oim->im6_msgtype = MRT6MSG_NOCACHE;
1236 				oim->im6_mbz = 0;
1237 				break;
1238 #endif
1239 			case MRT6_INIT:
1240 				im = mtod(mm, struct mrt6msg *);
1241 				im->im6_msgtype = MRT6MSG_NOCACHE;
1242 				im->im6_mbz = 0;
1243 				break;
1244 			default:
1245 				free(rte, M_MRTABLE6);
1246 				m_freem(mb0);
1247 				free(rt, M_MRTABLE6);
1248 				MFC6_UNLOCK();
1249 				return (EINVAL);
1250 			}
1251 
1252 #ifdef MRT6DEBUG
1253 			if (V_mrt6debug & DEBUG_FORWARD)
1254 				log(LOG_DEBUG,
1255 				    "getting the iif info in the kernel\n");
1256 #endif
1257 
1258 			for (mifp = mif6table, mifi = 0;
1259 			     mifi < nummifs && mifp->m6_ifp != ifp;
1260 			     mifp++, mifi++)
1261 				;
1262 
1263 			switch (V_ip6_mrouter_ver) {
1264 #ifdef MRT6_OINIT
1265 			case MRT6_OINIT:
1266 				oim->im6_mif = mifi;
1267 				break;
1268 #endif
1269 			case MRT6_INIT:
1270 				im->im6_mif = mifi;
1271 				break;
1272 			}
1273 
1274 			if (socket_send(V_ip6_mrouter, mm, &sin6) < 0) {
1275 				log(LOG_WARNING, "ip6_mforward: ip6_mrouter "
1276 				    "socket queue full\n");
1277 				MRT6STAT_INC(mrt6s_upq_sockfull);
1278 				free(rte, M_MRTABLE6);
1279 				m_freem(mb0);
1280 				free(rt, M_MRTABLE6);
1281 				MFC6_UNLOCK();
1282 				return (ENOBUFS);
1283 			}
1284 
1285 			MRT6STAT_INC(mrt6s_upcalls);
1286 
1287 			/* insert new entry at head of hash chain */
1288 			bzero(rt, sizeof(*rt));
1289 			rt->mf6c_origin.sin6_family = AF_INET6;
1290 			rt->mf6c_origin.sin6_len = sizeof(struct sockaddr_in6);
1291 			rt->mf6c_origin.sin6_addr = ip6->ip6_src;
1292 			rt->mf6c_mcastgrp.sin6_family = AF_INET6;
1293 			rt->mf6c_mcastgrp.sin6_len = sizeof(struct sockaddr_in6);
1294 			rt->mf6c_mcastgrp.sin6_addr = ip6->ip6_dst;
1295 			rt->mf6c_expire = UPCALL_EXPIRE;
1296 			n6expire[hash]++;
1297 			rt->mf6c_parent = MF6C_INCOMPLETE_PARENT;
1298 
1299 			/* link into table */
1300 			rt->mf6c_next  = mf6ctable[hash];
1301 			mf6ctable[hash] = rt;
1302 			/* Add this entry to the end of the queue */
1303 			rt->mf6c_stall = rte;
1304 		} else {
1305 			/* determine if q has overflowed */
1306 			struct rtdetq **p;
1307 			int npkts = 0;
1308 
1309 			for (p = &rt->mf6c_stall; *p != NULL; p = &(*p)->next)
1310 				if (++npkts > MAX_UPQ6) {
1311 					MRT6STAT_INC(mrt6s_upq_ovflw);
1312 					free(rte, M_MRTABLE6);
1313 					m_freem(mb0);
1314 					MFC6_UNLOCK();
1315 					return (0);
1316 				}
1317 
1318 			/* Add this entry to the end of the queue */
1319 			*p = rte;
1320 		}
1321 
1322 		rte->next = NULL;
1323 		rte->m = mb0;
1324 		rte->ifp = ifp;
1325 #ifdef UPCALL_TIMING
1326 		rte->t = tp;
1327 #endif /* UPCALL_TIMING */
1328 
1329 		MFC6_UNLOCK();
1330 
1331 		return (0);
1332 	}
1333 }
1334 
1335 /*
1336  * Clean up cache entries if upcalls are not serviced
1337  * Call from the Slow Timeout mechanism, every half second.
1338  */
1339 static void
1340 expire_upcalls(void *unused)
1341 {
1342 	struct rtdetq *rte;
1343 	struct mf6c *mfc, **nptr;
1344 	u_long i;
1345 
1346 	MFC6_LOCK();
1347 	for (i = 0; i < MF6CTBLSIZ; i++) {
1348 		if (n6expire[i] == 0)
1349 			continue;
1350 		nptr = &mf6ctable[i];
1351 		while ((mfc = *nptr) != NULL) {
1352 			rte = mfc->mf6c_stall;
1353 			/*
1354 			 * Skip real cache entries
1355 			 * Make sure it wasn't marked to not expire (shouldn't happen)
1356 			 * If it expires now
1357 			 */
1358 			if (rte != NULL &&
1359 			    mfc->mf6c_expire != 0 &&
1360 			    --mfc->mf6c_expire == 0) {
1361 #ifdef MRT6DEBUG
1362 				if (V_mrt6debug & DEBUG_EXPIRE) {
1363 					char ip6bufo[INET6_ADDRSTRLEN];
1364 					char ip6bufg[INET6_ADDRSTRLEN];
1365 					log(LOG_DEBUG, "expire_upcalls: expiring (%s %s)\n",
1366 					    ip6_sprintf(ip6bufo, &mfc->mf6c_origin.sin6_addr),
1367 					    ip6_sprintf(ip6bufg, &mfc->mf6c_mcastgrp.sin6_addr));
1368 				}
1369 #endif
1370 				/*
1371 				 * drop all the packets
1372 				 * free the mbuf with the pkt, if, timing info
1373 				 */
1374 				do {
1375 					struct rtdetq *n = rte->next;
1376 					m_freem(rte->m);
1377 					free(rte, M_MRTABLE6);
1378 					rte = n;
1379 				} while (rte != NULL);
1380 				MRT6STAT_INC(mrt6s_cache_cleanups);
1381 				n6expire[i]--;
1382 
1383 				*nptr = mfc->mf6c_next;
1384 				free(mfc, M_MRTABLE6);
1385 			} else {
1386 				nptr = &mfc->mf6c_next;
1387 			}
1388 		}
1389 	}
1390 	MFC6_UNLOCK();
1391 	callout_reset(&expire_upcalls_ch, EXPIRE_TIMEOUT,
1392 	    expire_upcalls, NULL);
1393 }
1394 
1395 /*
1396  * Packet forwarding routine once entry in the cache is made
1397  */
1398 static int
1399 ip6_mdq(struct mbuf *m, struct ifnet *ifp, struct mf6c *rt)
1400 {
1401 	struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1402 	mifi_t mifi, iif;
1403 	struct mif6 *mifp;
1404 	int plen = m->m_pkthdr.len;
1405 	struct in6_addr src0, dst0; /* copies for local work */
1406 	u_int32_t iszone, idzone, oszone, odzone;
1407 	int error = 0;
1408 
1409 /*
1410  * Macro to send packet on mif.  Since RSVP packets don't get counted on
1411  * input, they shouldn't get counted on output, so statistics keeping is
1412  * separate.
1413  */
1414 
1415 #define MC6_SEND(ip6, mifp, m) do {				\
1416 	if ((mifp)->m6_flags & MIFF_REGISTER)			\
1417 		register_send((ip6), (mifp), (m));		\
1418 	else							\
1419 		phyint_send((ip6), (mifp), (m));		\
1420 } while (/*CONSTCOND*/ 0)
1421 
1422 	/*
1423 	 * Don't forward if it didn't arrive from the parent mif
1424 	 * for its origin.
1425 	 */
1426 	mifi = rt->mf6c_parent;
1427 	if ((mifi >= nummifs) || (mif6table[mifi].m6_ifp != ifp)) {
1428 		/* came in the wrong interface */
1429 #ifdef MRT6DEBUG
1430 		if (V_mrt6debug & DEBUG_FORWARD)
1431 			log(LOG_DEBUG,
1432 			    "wrong if: ifid %d mifi %d mififid %x\n",
1433 			    ifp->if_index, mifi,
1434 			    mif6table[mifi].m6_ifp->if_index);
1435 #endif
1436 		MRT6STAT_INC(mrt6s_wrong_if);
1437 		rt->mf6c_wrong_if++;
1438 		/*
1439 		 * If we are doing PIM processing, and we are forwarding
1440 		 * packets on this interface, send a message to the
1441 		 * routing daemon.
1442 		 */
1443 		/* have to make sure this is a valid mif */
1444 		if (mifi < nummifs && mif6table[mifi].m6_ifp)
1445 			if (V_pim6 && (m->m_flags & M_LOOP) == 0) {
1446 				/*
1447 				 * Check the M_LOOP flag to avoid an
1448 				 * unnecessary PIM assert.
1449 				 * XXX: M_LOOP is an ad-hoc hack...
1450 				 */
1451 				static struct sockaddr_in6 sin6 =
1452 				{ sizeof(sin6), AF_INET6 };
1453 
1454 				struct mbuf *mm;
1455 				struct mrt6msg *im;
1456 #ifdef MRT6_OINIT
1457 				struct omrt6msg *oim;
1458 #endif
1459 
1460 				mm = m_copy(m, 0, sizeof(struct ip6_hdr));
1461 				if (mm &&
1462 				    (M_HASCL(mm) ||
1463 				     mm->m_len < sizeof(struct ip6_hdr)))
1464 					mm = m_pullup(mm, sizeof(struct ip6_hdr));
1465 				if (mm == NULL)
1466 					return (ENOBUFS);
1467 
1468 #ifdef MRT6_OINIT
1469 				oim = NULL;
1470 #endif
1471 				im = NULL;
1472 				switch (V_ip6_mrouter_ver) {
1473 #ifdef MRT6_OINIT
1474 				case MRT6_OINIT:
1475 					oim = mtod(mm, struct omrt6msg *);
1476 					oim->im6_msgtype = MRT6MSG_WRONGMIF;
1477 					oim->im6_mbz = 0;
1478 					break;
1479 #endif
1480 				case MRT6_INIT:
1481 					im = mtod(mm, struct mrt6msg *);
1482 					im->im6_msgtype = MRT6MSG_WRONGMIF;
1483 					im->im6_mbz = 0;
1484 					break;
1485 				default:
1486 					m_freem(mm);
1487 					return (EINVAL);
1488 				}
1489 
1490 				for (mifp = mif6table, iif = 0;
1491 				     iif < nummifs && mifp &&
1492 					     mifp->m6_ifp != ifp;
1493 				     mifp++, iif++)
1494 					;
1495 
1496 				switch (V_ip6_mrouter_ver) {
1497 #ifdef MRT6_OINIT
1498 				case MRT6_OINIT:
1499 					oim->im6_mif = iif;
1500 					sin6.sin6_addr = oim->im6_src;
1501 					break;
1502 #endif
1503 				case MRT6_INIT:
1504 					im->im6_mif = iif;
1505 					sin6.sin6_addr = im->im6_src;
1506 					break;
1507 				}
1508 
1509 				MRT6STAT_INC(mrt6s_upcalls);
1510 
1511 				if (socket_send(V_ip6_mrouter, mm, &sin6) < 0) {
1512 #ifdef MRT6DEBUG
1513 					if (V_mrt6debug)
1514 						log(LOG_WARNING, "mdq, ip6_mrouter socket queue full\n");
1515 #endif
1516 					MRT6STAT_INC(mrt6s_upq_sockfull);
1517 					return (ENOBUFS);
1518 				}	/* if socket Q full */
1519 			}		/* if PIM */
1520 		return (0);
1521 	}			/* if wrong iif */
1522 
1523 	/* If I sourced this packet, it counts as output, else it was input. */
1524 	if (m->m_pkthdr.rcvif == NULL) {
1525 		/* XXX: is rcvif really NULL when output?? */
1526 		mif6table[mifi].m6_pkt_out++;
1527 		mif6table[mifi].m6_bytes_out += plen;
1528 	} else {
1529 		mif6table[mifi].m6_pkt_in++;
1530 		mif6table[mifi].m6_bytes_in += plen;
1531 	}
1532 	rt->mf6c_pkt_cnt++;
1533 	rt->mf6c_byte_cnt += plen;
1534 
1535 	/*
1536 	 * For each mif, forward a copy of the packet if there are group
1537 	 * members downstream on the interface.
1538 	 */
1539 	src0 = ip6->ip6_src;
1540 	dst0 = ip6->ip6_dst;
1541 	if ((error = in6_setscope(&src0, ifp, &iszone)) != 0 ||
1542 	    (error = in6_setscope(&dst0, ifp, &idzone)) != 0) {
1543 		IP6STAT_INC(ip6s_badscope);
1544 		return (error);
1545 	}
1546 	for (mifp = mif6table, mifi = 0; mifi < nummifs; mifp++, mifi++) {
1547 		if (IF_ISSET(mifi, &rt->mf6c_ifset)) {
1548 			/*
1549 			 * check if the outgoing packet is going to break
1550 			 * a scope boundary.
1551 			 * XXX For packets through PIM register tunnel
1552 			 * interface, we believe a routing daemon.
1553 			 */
1554 			if (!(mif6table[rt->mf6c_parent].m6_flags &
1555 			      MIFF_REGISTER) &&
1556 			    !(mif6table[mifi].m6_flags & MIFF_REGISTER)) {
1557 				if (in6_setscope(&src0, mif6table[mifi].m6_ifp,
1558 				    &oszone) ||
1559 				    in6_setscope(&dst0, mif6table[mifi].m6_ifp,
1560 				    &odzone) ||
1561 				    iszone != oszone ||
1562 				    idzone != odzone) {
1563 					IP6STAT_INC(ip6s_badscope);
1564 					continue;
1565 				}
1566 			}
1567 
1568 			mifp->m6_pkt_out++;
1569 			mifp->m6_bytes_out += plen;
1570 			MC6_SEND(ip6, mifp, m);
1571 		}
1572 	}
1573 	return (0);
1574 }
1575 
1576 static void
1577 phyint_send(struct ip6_hdr *ip6, struct mif6 *mifp, struct mbuf *m)
1578 {
1579 	struct mbuf *mb_copy;
1580 	struct ifnet *ifp = mifp->m6_ifp;
1581 	int error = 0;
1582 	u_long linkmtu;
1583 
1584 	/*
1585 	 * Make a new reference to the packet; make sure that
1586 	 * the IPv6 header is actually copied, not just referenced,
1587 	 * so that ip6_output() only scribbles on the copy.
1588 	 */
1589 	mb_copy = m_copy(m, 0, M_COPYALL);
1590 	if (mb_copy &&
1591 	    (M_HASCL(mb_copy) || mb_copy->m_len < sizeof(struct ip6_hdr)))
1592 		mb_copy = m_pullup(mb_copy, sizeof(struct ip6_hdr));
1593 	if (mb_copy == NULL) {
1594 		return;
1595 	}
1596 	/* set MCAST flag to the outgoing packet */
1597 	mb_copy->m_flags |= M_MCAST;
1598 
1599 	/*
1600 	 * If we sourced the packet, call ip6_output since we may devide
1601 	 * the packet into fragments when the packet is too big for the
1602 	 * outgoing interface.
1603 	 * Otherwise, we can simply send the packet to the interface
1604 	 * sending queue.
1605 	 */
1606 	if (m->m_pkthdr.rcvif == NULL) {
1607 		struct ip6_moptions im6o;
1608 
1609 		im6o.im6o_multicast_ifp = ifp;
1610 		/* XXX: ip6_output will override ip6->ip6_hlim */
1611 		im6o.im6o_multicast_hlim = ip6->ip6_hlim;
1612 		im6o.im6o_multicast_loop = 1;
1613 		error = ip6_output(mb_copy, NULL, NULL, IPV6_FORWARDING, &im6o,
1614 		    NULL, NULL);
1615 
1616 #ifdef MRT6DEBUG
1617 		if (V_mrt6debug & DEBUG_XMIT)
1618 			log(LOG_DEBUG, "phyint_send on mif %d err %d\n",
1619 			    mifp - mif6table, error);
1620 #endif
1621 		return;
1622 	}
1623 
1624 	/*
1625 	 * If configured to loop back multicasts by default,
1626 	 * loop back a copy now.
1627 	 */
1628 	if (in6_mcast_loop) {
1629 		struct sockaddr_in6 dst6;
1630 
1631 		bzero(&dst6, sizeof(dst6));
1632 		dst6.sin6_len = sizeof(struct sockaddr_in6);
1633 		dst6.sin6_family = AF_INET6;
1634 		dst6.sin6_addr = ip6->ip6_dst;
1635 		ip6_mloopback(ifp, m, &dst6);
1636 	}
1637 
1638 	/*
1639 	 * Put the packet into the sending queue of the outgoing interface
1640 	 * if it would fit in the MTU of the interface.
1641 	 */
1642 	linkmtu = IN6_LINKMTU(ifp);
1643 	if (mb_copy->m_pkthdr.len <= linkmtu || linkmtu < IPV6_MMTU) {
1644 		struct sockaddr_in6 dst6;
1645 
1646 		bzero(&dst6, sizeof(dst6));
1647 		dst6.sin6_len = sizeof(struct sockaddr_in6);
1648 		dst6.sin6_family = AF_INET6;
1649 		dst6.sin6_addr = ip6->ip6_dst;
1650 
1651 		IP_PROBE(send, NULL, NULL, ip6, ifp, NULL, ip6);
1652 		/*
1653 		 * We just call if_output instead of nd6_output here, since
1654 		 * we need no ND for a multicast forwarded packet...right?
1655 		 */
1656 		m_clrprotoflags(m);	/* Avoid confusing lower layers. */
1657 		error = (*ifp->if_output)(ifp, mb_copy,
1658 		    (struct sockaddr *)&dst6, NULL);
1659 #ifdef MRT6DEBUG
1660 		if (V_mrt6debug & DEBUG_XMIT)
1661 			log(LOG_DEBUG, "phyint_send on mif %d err %d\n",
1662 			    mifp - mif6table, error);
1663 #endif
1664 	} else {
1665 		/*
1666 		 * pMTU discovery is intentionally disabled by default, since
1667 		 * various router may notify pMTU in multicast, which can be
1668 		 * a DDoS to a router
1669 		 */
1670 		if (V_ip6_mcast_pmtu)
1671 			icmp6_error(mb_copy, ICMP6_PACKET_TOO_BIG, 0, linkmtu);
1672 		else {
1673 #ifdef MRT6DEBUG
1674 			if (V_mrt6debug & DEBUG_XMIT) {
1675 				char ip6bufs[INET6_ADDRSTRLEN];
1676 				char ip6bufd[INET6_ADDRSTRLEN];
1677 				log(LOG_DEBUG,
1678 				    "phyint_send: packet too big on %s o %s "
1679 				    "g %s size %d(discarded)\n",
1680 				    if_name(ifp),
1681 				    ip6_sprintf(ip6bufs, &ip6->ip6_src),
1682 				    ip6_sprintf(ip6bufd, &ip6->ip6_dst),
1683 				    mb_copy->m_pkthdr.len);
1684 			}
1685 #endif /* MRT6DEBUG */
1686 			m_freem(mb_copy); /* simply discard the packet */
1687 		}
1688 	}
1689 }
1690 
1691 static int
1692 register_send(struct ip6_hdr *ip6, struct mif6 *mif, struct mbuf *m)
1693 {
1694 	struct mbuf *mm;
1695 	int i, len = m->m_pkthdr.len;
1696 	static struct sockaddr_in6 sin6 = { sizeof(sin6), AF_INET6 };
1697 	struct mrt6msg *im6;
1698 
1699 #ifdef MRT6DEBUG
1700 	if (V_mrt6debug) {
1701 		char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
1702 		log(LOG_DEBUG, "** IPv6 register_send **\n src %s dst %s\n",
1703 		    ip6_sprintf(ip6bufs, &ip6->ip6_src),
1704 		    ip6_sprintf(ip6bufd, &ip6->ip6_dst));
1705 	}
1706 #endif
1707 	PIM6STAT_INC(pim6s_snd_registers);
1708 
1709 	/* Make a copy of the packet to send to the user level process. */
1710 	mm = m_gethdr(M_NOWAIT, MT_DATA);
1711 	if (mm == NULL)
1712 		return (ENOBUFS);
1713 	mm->m_data += max_linkhdr;
1714 	mm->m_len = sizeof(struct ip6_hdr);
1715 
1716 	if ((mm->m_next = m_copy(m, 0, M_COPYALL)) == NULL) {
1717 		m_freem(mm);
1718 		return (ENOBUFS);
1719 	}
1720 	i = MHLEN - M_LEADINGSPACE(mm);
1721 	if (i > len)
1722 		i = len;
1723 	mm = m_pullup(mm, i);
1724 	if (mm == NULL)
1725 		return (ENOBUFS);
1726 /* TODO: check it! */
1727 	mm->m_pkthdr.len = len + sizeof(struct ip6_hdr);
1728 
1729 	/*
1730 	 * Send message to routing daemon
1731 	 */
1732 	sin6.sin6_addr = ip6->ip6_src;
1733 
1734 	im6 = mtod(mm, struct mrt6msg *);
1735 	im6->im6_msgtype      = MRT6MSG_WHOLEPKT;
1736 	im6->im6_mbz          = 0;
1737 
1738 	im6->im6_mif = mif - mif6table;
1739 
1740 	/* iif info is not given for reg. encap.n */
1741 	MRT6STAT_INC(mrt6s_upcalls);
1742 
1743 	if (socket_send(V_ip6_mrouter, mm, &sin6) < 0) {
1744 #ifdef MRT6DEBUG
1745 		if (V_mrt6debug)
1746 			log(LOG_WARNING,
1747 			    "register_send: ip6_mrouter socket queue full\n");
1748 #endif
1749 		MRT6STAT_INC(mrt6s_upq_sockfull);
1750 		return (ENOBUFS);
1751 	}
1752 	return (0);
1753 }
1754 
1755 /*
1756  * pim6_encapcheck() is called by the encap6_input() path at runtime to
1757  * determine if a packet is for PIM; allowing PIM to be dynamically loaded
1758  * into the kernel.
1759  */
1760 static int
1761 pim6_encapcheck(const struct mbuf *m, int off, int proto, void *arg)
1762 {
1763 
1764 #ifdef DIAGNOSTIC
1765     KASSERT(proto == IPPROTO_PIM, ("not for IPPROTO_PIM"));
1766 #endif
1767     if (proto != IPPROTO_PIM)
1768 	return 0;	/* not for us; reject the datagram. */
1769 
1770     return 64;		/* claim the datagram. */
1771 }
1772 
1773 /*
1774  * PIM sparse mode hook
1775  * Receives the pim control messages, and passes them up to the listening
1776  * socket, using rip6_input.
1777  * The only message processed is the REGISTER pim message; the pim header
1778  * is stripped off, and the inner packet is passed to register_mforward.
1779  */
1780 int
1781 pim6_input(struct mbuf **mp, int *offp, int proto)
1782 {
1783 	struct pim *pim; /* pointer to a pim struct */
1784 	struct ip6_hdr *ip6;
1785 	int pimlen;
1786 	struct mbuf *m = *mp;
1787 	int minlen;
1788 	int off = *offp;
1789 
1790 	PIM6STAT_INC(pim6s_rcv_total);
1791 
1792 	ip6 = mtod(m, struct ip6_hdr *);
1793 	pimlen = m->m_pkthdr.len - *offp;
1794 
1795 	/*
1796 	 * Validate lengths
1797 	 */
1798 	if (pimlen < PIM_MINLEN) {
1799 		PIM6STAT_INC(pim6s_rcv_tooshort);
1800 #ifdef MRT6DEBUG
1801 		if (V_mrt6debug & DEBUG_PIM)
1802 			log(LOG_DEBUG,"pim6_input: PIM packet too short\n");
1803 #endif
1804 		m_freem(m);
1805 		return (IPPROTO_DONE);
1806 	}
1807 
1808 	/*
1809 	 * if the packet is at least as big as a REGISTER, go ahead
1810 	 * and grab the PIM REGISTER header size, to avoid another
1811 	 * possible m_pullup() later.
1812 	 *
1813 	 * PIM_MINLEN       == pimhdr + u_int32 == 8
1814 	 * PIM6_REG_MINLEN   == pimhdr + reghdr + eip6hdr == 4 + 4 + 40
1815 	 */
1816 	minlen = (pimlen >= PIM6_REG_MINLEN) ? PIM6_REG_MINLEN : PIM_MINLEN;
1817 
1818 	/*
1819 	 * Make sure that the IP6 and PIM headers in contiguous memory, and
1820 	 * possibly the PIM REGISTER header
1821 	 */
1822 #ifndef PULLDOWN_TEST
1823 	IP6_EXTHDR_CHECK(m, off, minlen, IPPROTO_DONE);
1824 	/* adjust pointer */
1825 	ip6 = mtod(m, struct ip6_hdr *);
1826 
1827 	/* adjust mbuf to point to the PIM header */
1828 	pim = (struct pim *)((caddr_t)ip6 + off);
1829 #else
1830 	IP6_EXTHDR_GET(pim, struct pim *, m, off, minlen);
1831 	if (pim == NULL) {
1832 		PIM6STAT_INC(pim6s_rcv_tooshort);
1833 		return (IPPROTO_DONE);
1834 	}
1835 #endif
1836 
1837 #define PIM6_CHECKSUM
1838 #ifdef PIM6_CHECKSUM
1839 	{
1840 		int cksumlen;
1841 
1842 		/*
1843 		 * Validate checksum.
1844 		 * If PIM REGISTER, exclude the data packet
1845 		 */
1846 		if (pim->pim_type == PIM_REGISTER)
1847 			cksumlen = PIM_MINLEN;
1848 		else
1849 			cksumlen = pimlen;
1850 
1851 		if (in6_cksum(m, IPPROTO_PIM, off, cksumlen)) {
1852 			PIM6STAT_INC(pim6s_rcv_badsum);
1853 #ifdef MRT6DEBUG
1854 			if (V_mrt6debug & DEBUG_PIM)
1855 				log(LOG_DEBUG,
1856 				    "pim6_input: invalid checksum\n");
1857 #endif
1858 			m_freem(m);
1859 			return (IPPROTO_DONE);
1860 		}
1861 	}
1862 #endif /* PIM_CHECKSUM */
1863 
1864 	/* PIM version check */
1865 	if (pim->pim_ver != PIM_VERSION) {
1866 		PIM6STAT_INC(pim6s_rcv_badversion);
1867 #ifdef MRT6DEBUG
1868 		log(LOG_ERR,
1869 		    "pim6_input: incorrect version %d, expecting %d\n",
1870 		    pim->pim_ver, PIM_VERSION);
1871 #endif
1872 		m_freem(m);
1873 		return (IPPROTO_DONE);
1874 	}
1875 
1876 	if (pim->pim_type == PIM_REGISTER) {
1877 		/*
1878 		 * since this is a REGISTER, we'll make a copy of the register
1879 		 * headers ip6+pim+u_int32_t+encap_ip6, to be passed up to the
1880 		 * routing daemon.
1881 		 */
1882 		static struct sockaddr_in6 dst = { sizeof(dst), AF_INET6 };
1883 
1884 		struct mbuf *mcp;
1885 		struct ip6_hdr *eip6;
1886 		u_int32_t *reghdr;
1887 		int rc;
1888 #ifdef MRT6DEBUG
1889 		char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
1890 #endif
1891 
1892 		PIM6STAT_INC(pim6s_rcv_registers);
1893 
1894 		if ((reg_mif_num >= nummifs) || (reg_mif_num == (mifi_t) -1)) {
1895 #ifdef MRT6DEBUG
1896 			if (V_mrt6debug & DEBUG_PIM)
1897 				log(LOG_DEBUG,
1898 				    "pim6_input: register mif not set: %d\n",
1899 				    reg_mif_num);
1900 #endif
1901 			m_freem(m);
1902 			return (IPPROTO_DONE);
1903 		}
1904 
1905 		reghdr = (u_int32_t *)(pim + 1);
1906 
1907 		if ((ntohl(*reghdr) & PIM_NULL_REGISTER))
1908 			goto pim6_input_to_daemon;
1909 
1910 		/*
1911 		 * Validate length
1912 		 */
1913 		if (pimlen < PIM6_REG_MINLEN) {
1914 			PIM6STAT_INC(pim6s_rcv_tooshort);
1915 			PIM6STAT_INC(pim6s_rcv_badregisters);
1916 #ifdef MRT6DEBUG
1917 			log(LOG_ERR,
1918 			    "pim6_input: register packet size too "
1919 			    "small %d from %s\n",
1920 			    pimlen, ip6_sprintf(ip6bufs, &ip6->ip6_src));
1921 #endif
1922 			m_freem(m);
1923 			return (IPPROTO_DONE);
1924 		}
1925 
1926 		eip6 = (struct ip6_hdr *) (reghdr + 1);
1927 #ifdef MRT6DEBUG
1928 		if (V_mrt6debug & DEBUG_PIM)
1929 			log(LOG_DEBUG,
1930 			    "pim6_input[register], eip6: %s -> %s, "
1931 			    "eip6 plen %d\n",
1932 			    ip6_sprintf(ip6bufs, &eip6->ip6_src),
1933 			    ip6_sprintf(ip6bufd, &eip6->ip6_dst),
1934 			    ntohs(eip6->ip6_plen));
1935 #endif
1936 
1937 		/* verify the version number of the inner packet */
1938 		if ((eip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
1939 			PIM6STAT_INC(pim6s_rcv_badregisters);
1940 #ifdef MRT6DEBUG
1941 			log(LOG_DEBUG, "pim6_input: invalid IP version (%d) "
1942 			    "of the inner packet\n",
1943 			    (eip6->ip6_vfc & IPV6_VERSION));
1944 #endif
1945 			m_freem(m);
1946 			return (IPPROTO_NONE);
1947 		}
1948 
1949 		/* verify the inner packet is destined to a mcast group */
1950 		if (!IN6_IS_ADDR_MULTICAST(&eip6->ip6_dst)) {
1951 			PIM6STAT_INC(pim6s_rcv_badregisters);
1952 #ifdef MRT6DEBUG
1953 			if (V_mrt6debug & DEBUG_PIM)
1954 				log(LOG_DEBUG,
1955 				    "pim6_input: inner packet of register "
1956 				    "is not multicast %s\n",
1957 				    ip6_sprintf(ip6bufd, &eip6->ip6_dst));
1958 #endif
1959 			m_freem(m);
1960 			return (IPPROTO_DONE);
1961 		}
1962 
1963 		/*
1964 		 * make a copy of the whole header to pass to the daemon later.
1965 		 */
1966 		mcp = m_copy(m, 0, off + PIM6_REG_MINLEN);
1967 		if (mcp == NULL) {
1968 #ifdef MRT6DEBUG
1969 			log(LOG_ERR,
1970 			    "pim6_input: pim register: "
1971 			    "could not copy register head\n");
1972 #endif
1973 			m_freem(m);
1974 			return (IPPROTO_DONE);
1975 		}
1976 
1977 		/*
1978 		 * forward the inner ip6 packet; point m_data at the inner ip6.
1979 		 */
1980 		m_adj(m, off + PIM_MINLEN);
1981 #ifdef MRT6DEBUG
1982 		if (V_mrt6debug & DEBUG_PIM) {
1983 			log(LOG_DEBUG,
1984 			    "pim6_input: forwarding decapsulated register: "
1985 			    "src %s, dst %s, mif %d\n",
1986 			    ip6_sprintf(ip6bufs, &eip6->ip6_src),
1987 			    ip6_sprintf(ip6bufd, &eip6->ip6_dst),
1988 			    reg_mif_num);
1989 		}
1990 #endif
1991 
1992 		rc = if_simloop(mif6table[reg_mif_num].m6_ifp, m,
1993 				dst.sin6_family, 0);
1994 
1995 		/* prepare the register head to send to the mrouting daemon */
1996 		m = mcp;
1997 	}
1998 
1999 	/*
2000 	 * Pass the PIM message up to the daemon; if it is a register message
2001 	 * pass the 'head' only up to the daemon. This includes the
2002 	 * encapsulator ip6 header, pim header, register header and the
2003 	 * encapsulated ip6 header.
2004 	 */
2005   pim6_input_to_daemon:
2006 	rip6_input(&m, offp, proto);
2007 	return (IPPROTO_DONE);
2008 }
2009 
2010 static int
2011 ip6_mroute_modevent(module_t mod, int type, void *unused)
2012 {
2013 
2014 	switch (type) {
2015 	case MOD_LOAD:
2016 		MROUTER6_LOCK_INIT();
2017 		MFC6_LOCK_INIT();
2018 		MIF6_LOCK_INIT();
2019 
2020 		pim6_encap_cookie = encap_attach_func(AF_INET6, IPPROTO_PIM,
2021 			pim6_encapcheck,
2022 			(const struct protosw *)&in6_pim_protosw, NULL);
2023 		if (pim6_encap_cookie == NULL) {
2024 			printf("ip6_mroute: unable to attach pim6 encap\n");
2025 			MIF6_LOCK_DESTROY();
2026 			MFC6_LOCK_DESTROY();
2027 			MROUTER6_LOCK_DESTROY();
2028 			return (EINVAL);
2029 		}
2030 
2031 		ip6_mforward = X_ip6_mforward;
2032 		ip6_mrouter_done = X_ip6_mrouter_done;
2033 		ip6_mrouter_get = X_ip6_mrouter_get;
2034 		ip6_mrouter_set = X_ip6_mrouter_set;
2035 		mrt6_ioctl = X_mrt6_ioctl;
2036 		break;
2037 
2038 	case MOD_UNLOAD:
2039 		if (V_ip6_mrouter != NULL)
2040 			return EINVAL;
2041 
2042 		if (pim6_encap_cookie) {
2043 			encap_detach(pim6_encap_cookie);
2044 			pim6_encap_cookie = NULL;
2045 		}
2046 		X_ip6_mrouter_done();
2047 		ip6_mforward = NULL;
2048 		ip6_mrouter_done = NULL;
2049 		ip6_mrouter_get = NULL;
2050 		ip6_mrouter_set = NULL;
2051 		mrt6_ioctl = NULL;
2052 
2053 		MIF6_LOCK_DESTROY();
2054 		MFC6_LOCK_DESTROY();
2055 		MROUTER6_LOCK_DESTROY();
2056 		break;
2057 
2058 	default:
2059 		return (EOPNOTSUPP);
2060 	}
2061 
2062 	return (0);
2063 }
2064 
2065 static moduledata_t ip6_mroutemod = {
2066 	"ip6_mroute",
2067 	ip6_mroute_modevent,
2068 	0
2069 };
2070 
2071 DECLARE_MODULE(ip6_mroute, ip6_mroutemod, SI_SUB_PSEUDO, SI_ORDER_ANY);
2072