xref: /freebsd/sys/netinet/in_mcast.c (revision ccfd87fe2ac0e2e6aeb1911a7d7cce6712a8564f)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 2007-2009 Bruce Simpson.
5  * Copyright (c) 2005 Robert N. M. Watson.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. The name of the author may not be used to endorse or promote
17  *    products derived from this software without specific prior written
18  *    permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 /*
34  * IPv4 multicast socket, group, and socket option processing module.
35  */
36 
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
39 
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/kernel.h>
43 #include <sys/lock.h>
44 #include <sys/malloc.h>
45 #include <sys/mbuf.h>
46 #include <sys/protosw.h>
47 #include <sys/socket.h>
48 #include <sys/socketvar.h>
49 #include <sys/protosw.h>
50 #include <sys/sysctl.h>
51 #include <sys/ktr.h>
52 #include <sys/taskqueue.h>
53 #include <sys/tree.h>
54 
55 #include <net/if.h>
56 #include <net/if_var.h>
57 #include <net/if_dl.h>
58 #include <net/route.h>
59 #include <net/route/nhop.h>
60 #include <net/vnet.h>
61 
62 #include <net/ethernet.h>
63 
64 #include <netinet/in.h>
65 #include <netinet/in_systm.h>
66 #include <netinet/in_fib.h>
67 #include <netinet/in_pcb.h>
68 #include <netinet/in_var.h>
69 #include <net/if_private.h>
70 #include <netinet/ip_var.h>
71 #include <netinet/igmp_var.h>
72 
73 #ifndef KTR_IGMPV3
74 #define KTR_IGMPV3 KTR_INET
75 #endif
76 
77 #ifndef __SOCKUNION_DECLARED
78 union sockunion {
79 	struct sockaddr_storage	ss;
80 	struct sockaddr		sa;
81 	struct sockaddr_dl	sdl;
82 	struct sockaddr_in	sin;
83 };
84 typedef union sockunion sockunion_t;
85 #define __SOCKUNION_DECLARED
86 #endif /* __SOCKUNION_DECLARED */
87 
88 static MALLOC_DEFINE(M_INMFILTER, "in_mfilter",
89     "IPv4 multicast PCB-layer source filter");
90 static MALLOC_DEFINE(M_IPMADDR, "in_multi", "IPv4 multicast group");
91 static MALLOC_DEFINE(M_IPMOPTS, "ip_moptions", "IPv4 multicast options");
92 static MALLOC_DEFINE(M_IPMSOURCE, "ip_msource",
93     "IPv4 multicast IGMP-layer source filter");
94 
95 /*
96  * Locking:
97  *
98  * - Lock order is: Giant, IN_MULTI_LOCK, INP_WLOCK,
99  *   IN_MULTI_LIST_LOCK, IGMP_LOCK, IF_ADDR_LOCK.
100  * - The IF_ADDR_LOCK is implicitly taken by inm_lookup() earlier, however
101  *   it can be taken by code in net/if.c also.
102  * - ip_moptions and in_mfilter are covered by the INP_WLOCK.
103  *
104  * struct in_multi is covered by IN_MULTI_LIST_LOCK. There isn't strictly
105  * any need for in_multi itself to be virtualized -- it is bound to an ifp
106  * anyway no matter what happens.
107  */
108 struct mtx in_multi_list_mtx;
109 MTX_SYSINIT(in_multi_mtx, &in_multi_list_mtx, "in_multi_list_mtx", MTX_DEF);
110 
111 struct mtx in_multi_free_mtx;
112 MTX_SYSINIT(in_multi_free_mtx, &in_multi_free_mtx, "in_multi_free_mtx", MTX_DEF);
113 
114 struct sx in_multi_sx;
115 SX_SYSINIT(in_multi_sx, &in_multi_sx, "in_multi_sx");
116 
117 /*
118  * Functions with non-static linkage defined in this file should be
119  * declared in in_var.h:
120  *  imo_multi_filter()
121  *  in_joingroup()
122  *  in_joingroup_locked()
123  *  in_leavegroup()
124  *  in_leavegroup_locked()
125  * and ip_var.h:
126  *  inp_freemoptions()
127  *  inp_getmoptions()
128  *  inp_setmoptions()
129  */
130 static void	imf_commit(struct in_mfilter *);
131 static int	imf_get_source(struct in_mfilter *imf,
132 		    const struct sockaddr_in *psin,
133 		    struct in_msource **);
134 static struct in_msource *
135 		imf_graft(struct in_mfilter *, const uint8_t,
136 		    const struct sockaddr_in *);
137 static void	imf_leave(struct in_mfilter *);
138 static int	imf_prune(struct in_mfilter *, const struct sockaddr_in *);
139 static void	imf_purge(struct in_mfilter *);
140 static void	imf_rollback(struct in_mfilter *);
141 static void	imf_reap(struct in_mfilter *);
142 static struct in_mfilter *
143 		imo_match_group(const struct ip_moptions *,
144 		    const struct ifnet *, const struct sockaddr *);
145 static struct in_msource *
146 		imo_match_source(struct in_mfilter *, const struct sockaddr *);
147 static void	ims_merge(struct ip_msource *ims,
148 		    const struct in_msource *lims, const int rollback);
149 static int	in_getmulti(struct ifnet *, const struct in_addr *,
150 		    struct in_multi **);
151 static int	inm_get_source(struct in_multi *inm, const in_addr_t haddr,
152 		    const int noalloc, struct ip_msource **pims);
153 #ifdef KTR
154 static int	inm_is_ifp_detached(const struct in_multi *);
155 #endif
156 static int	inm_merge(struct in_multi *, /*const*/ struct in_mfilter *);
157 static void	inm_purge(struct in_multi *);
158 static void	inm_reap(struct in_multi *);
159 static void inm_release(struct in_multi *);
160 static struct ip_moptions *
161 		inp_findmoptions(struct inpcb *);
162 static int	inp_get_source_filters(struct inpcb *, struct sockopt *);
163 static int	inp_join_group(struct inpcb *, struct sockopt *);
164 static int	inp_leave_group(struct inpcb *, struct sockopt *);
165 static struct ifnet *
166 		inp_lookup_mcast_ifp(const struct inpcb *,
167 		    const struct sockaddr_in *, const struct in_addr);
168 static int	inp_block_unblock_source(struct inpcb *, struct sockopt *);
169 static int	inp_set_multicast_if(struct inpcb *, struct sockopt *);
170 static int	inp_set_source_filters(struct inpcb *, struct sockopt *);
171 static int	sysctl_ip_mcast_filters(SYSCTL_HANDLER_ARGS);
172 
173 static SYSCTL_NODE(_net_inet_ip, OID_AUTO, mcast,
174     CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
175     "IPv4 multicast");
176 
177 static u_long in_mcast_maxgrpsrc = IP_MAX_GROUP_SRC_FILTER;
178 SYSCTL_ULONG(_net_inet_ip_mcast, OID_AUTO, maxgrpsrc,
179     CTLFLAG_RWTUN, &in_mcast_maxgrpsrc, 0,
180     "Max source filters per group");
181 
182 static u_long in_mcast_maxsocksrc = IP_MAX_SOCK_SRC_FILTER;
183 SYSCTL_ULONG(_net_inet_ip_mcast, OID_AUTO, maxsocksrc,
184     CTLFLAG_RWTUN, &in_mcast_maxsocksrc, 0,
185     "Max source filters per socket");
186 
187 int in_mcast_loop = IP_DEFAULT_MULTICAST_LOOP;
188 SYSCTL_INT(_net_inet_ip_mcast, OID_AUTO, loop, CTLFLAG_RWTUN,
189     &in_mcast_loop, 0, "Loopback multicast datagrams by default");
190 
191 static SYSCTL_NODE(_net_inet_ip_mcast, OID_AUTO, filters,
192     CTLFLAG_RD | CTLFLAG_MPSAFE, sysctl_ip_mcast_filters,
193     "Per-interface stack-wide source filters");
194 
195 #ifdef KTR
196 /*
197  * Inline function which wraps assertions for a valid ifp.
198  * The ifnet layer will set the ifma's ifp pointer to NULL if the ifp
199  * is detached.
200  */
201 static int __inline
202 inm_is_ifp_detached(const struct in_multi *inm)
203 {
204 	struct ifnet *ifp;
205 
206 	KASSERT(inm->inm_ifma != NULL, ("%s: no ifma", __func__));
207 	ifp = inm->inm_ifma->ifma_ifp;
208 	if (ifp != NULL) {
209 		/*
210 		 * Sanity check that netinet's notion of ifp is the
211 		 * same as net's.
212 		 */
213 		KASSERT(inm->inm_ifp == ifp, ("%s: bad ifp", __func__));
214 	}
215 
216 	return (ifp == NULL);
217 }
218 #endif
219 
220 /*
221  * Interface detach can happen in a taskqueue thread context, so we must use a
222  * dedicated thread to avoid deadlocks when draining inm_release tasks.
223  */
224 TASKQUEUE_DEFINE_THREAD(inm_free);
225 static struct in_multi_head inm_free_list = SLIST_HEAD_INITIALIZER();
226 static void inm_release_task(void *arg __unused, int pending __unused);
227 static struct task inm_free_task = TASK_INITIALIZER(0, inm_release_task, NULL);
228 
229 void
230 inm_release_wait(void *arg __unused)
231 {
232 
233 	/*
234 	 * Make sure all pending multicast addresses are freed before
235 	 * the VNET or network device is destroyed:
236 	 */
237 	taskqueue_drain(taskqueue_inm_free, &inm_free_task);
238 }
239 #ifdef VIMAGE
240 /* XXX-BZ FIXME, see D24914. */
241 VNET_SYSUNINIT(inm_release_wait, SI_SUB_PROTO_DOMAIN, SI_ORDER_FIRST, inm_release_wait, NULL);
242 #endif
243 
244 void
245 inm_release_list_deferred(struct in_multi_head *inmh)
246 {
247 
248 	if (SLIST_EMPTY(inmh))
249 		return;
250 	mtx_lock(&in_multi_free_mtx);
251 	SLIST_CONCAT(&inm_free_list, inmh, in_multi, inm_nrele);
252 	mtx_unlock(&in_multi_free_mtx);
253 	taskqueue_enqueue(taskqueue_inm_free, &inm_free_task);
254 }
255 
256 void
257 inm_disconnect(struct in_multi *inm)
258 {
259 	struct ifnet *ifp;
260 	struct ifmultiaddr *ifma, *ll_ifma;
261 
262 	ifp = inm->inm_ifp;
263 	IF_ADDR_WLOCK_ASSERT(ifp);
264 	ifma = inm->inm_ifma;
265 
266 	if_ref(ifp);
267 	if (ifma->ifma_flags & IFMA_F_ENQUEUED) {
268 		CK_STAILQ_REMOVE(&ifp->if_multiaddrs, ifma, ifmultiaddr, ifma_link);
269 		ifma->ifma_flags &= ~IFMA_F_ENQUEUED;
270 	}
271 	MCDPRINTF("removed ifma: %p from %s\n", ifma, ifp->if_xname);
272 	if ((ll_ifma = ifma->ifma_llifma) != NULL) {
273 		MPASS(ifma != ll_ifma);
274 		ifma->ifma_llifma = NULL;
275 		MPASS(ll_ifma->ifma_llifma == NULL);
276 		MPASS(ll_ifma->ifma_ifp == ifp);
277 		if (--ll_ifma->ifma_refcount == 0) {
278 			if (ll_ifma->ifma_flags & IFMA_F_ENQUEUED) {
279 				CK_STAILQ_REMOVE(&ifp->if_multiaddrs, ll_ifma, ifmultiaddr, ifma_link);
280 				ll_ifma->ifma_flags &= ~IFMA_F_ENQUEUED;
281 			}
282 			MCDPRINTF("removed ll_ifma: %p from %s\n", ll_ifma, ifp->if_xname);
283 			if_freemulti(ll_ifma);
284 		}
285 	}
286 }
287 
288 void
289 inm_release_deferred(struct in_multi *inm)
290 {
291 	struct in_multi_head tmp;
292 
293 	IN_MULTI_LIST_LOCK_ASSERT();
294 	MPASS(inm->inm_refcount > 0);
295 	if (--inm->inm_refcount == 0) {
296 		SLIST_INIT(&tmp);
297 		inm_disconnect(inm);
298 		inm->inm_ifma->ifma_protospec = NULL;
299 		SLIST_INSERT_HEAD(&tmp, inm, inm_nrele);
300 		inm_release_list_deferred(&tmp);
301 	}
302 }
303 
304 static void
305 inm_release_task(void *arg __unused, int pending __unused)
306 {
307 	struct in_multi_head inm_free_tmp;
308 	struct in_multi *inm, *tinm;
309 
310 	SLIST_INIT(&inm_free_tmp);
311 	mtx_lock(&in_multi_free_mtx);
312 	SLIST_CONCAT(&inm_free_tmp, &inm_free_list, in_multi, inm_nrele);
313 	mtx_unlock(&in_multi_free_mtx);
314 	IN_MULTI_LOCK();
315 	SLIST_FOREACH_SAFE(inm, &inm_free_tmp, inm_nrele, tinm) {
316 		SLIST_REMOVE_HEAD(&inm_free_tmp, inm_nrele);
317 		MPASS(inm);
318 		inm_release(inm);
319 	}
320 	IN_MULTI_UNLOCK();
321 }
322 
323 /*
324  * Initialize an in_mfilter structure to a known state at t0, t1
325  * with an empty source filter list.
326  */
327 static __inline void
328 imf_init(struct in_mfilter *imf, const int st0, const int st1)
329 {
330 	memset(imf, 0, sizeof(struct in_mfilter));
331 	RB_INIT(&imf->imf_sources);
332 	imf->imf_st[0] = st0;
333 	imf->imf_st[1] = st1;
334 }
335 
336 struct in_mfilter *
337 ip_mfilter_alloc(const int mflags, const int st0, const int st1)
338 {
339 	struct in_mfilter *imf;
340 
341 	imf = malloc(sizeof(*imf), M_INMFILTER, mflags);
342 	if (imf != NULL)
343 		imf_init(imf, st0, st1);
344 
345 	return (imf);
346 }
347 
348 void
349 ip_mfilter_free(struct in_mfilter *imf)
350 {
351 
352 	imf_purge(imf);
353 	free(imf, M_INMFILTER);
354 }
355 
356 /*
357  * Function for looking up an in_multi record for an IPv4 multicast address
358  * on a given interface. ifp must be valid. If no record found, return NULL.
359  * The IN_MULTI_LIST_LOCK and IF_ADDR_LOCK on ifp must be held.
360  */
361 struct in_multi *
362 inm_lookup_locked(struct ifnet *ifp, const struct in_addr ina)
363 {
364 	struct ifmultiaddr *ifma;
365 	struct in_multi *inm;
366 
367 	IN_MULTI_LIST_LOCK_ASSERT();
368 	IF_ADDR_LOCK_ASSERT(ifp);
369 
370 	CK_STAILQ_FOREACH(ifma, &((ifp)->if_multiaddrs), ifma_link) {
371 		inm = inm_ifmultiaddr_get_inm(ifma);
372 		if (inm == NULL)
373 			continue;
374 		if (inm->inm_addr.s_addr == ina.s_addr)
375 			return (inm);
376 	}
377 	return (NULL);
378 }
379 
380 /*
381  * Wrapper for inm_lookup_locked().
382  * The IF_ADDR_LOCK will be taken on ifp and released on return.
383  */
384 struct in_multi *
385 inm_lookup(struct ifnet *ifp, const struct in_addr ina)
386 {
387 	struct epoch_tracker et;
388 	struct in_multi *inm;
389 
390 	IN_MULTI_LIST_LOCK_ASSERT();
391 	NET_EPOCH_ENTER(et);
392 
393 	inm = inm_lookup_locked(ifp, ina);
394 	NET_EPOCH_EXIT(et);
395 
396 	return (inm);
397 }
398 
399 /*
400  * Find an IPv4 multicast group entry for this ip_moptions instance
401  * which matches the specified group, and optionally an interface.
402  * Return its index into the array, or -1 if not found.
403  */
404 static struct in_mfilter *
405 imo_match_group(const struct ip_moptions *imo, const struct ifnet *ifp,
406     const struct sockaddr *group)
407 {
408 	const struct sockaddr_in *gsin;
409 	struct in_mfilter *imf;
410 	struct in_multi	*inm;
411 
412 	gsin = (const struct sockaddr_in *)group;
413 
414 	IP_MFILTER_FOREACH(imf, &imo->imo_head) {
415 		inm = imf->imf_inm;
416 		if (inm == NULL)
417 			continue;
418 		if ((ifp == NULL || (inm->inm_ifp == ifp)) &&
419 		    in_hosteq(inm->inm_addr, gsin->sin_addr)) {
420 			break;
421 		}
422 	}
423 	return (imf);
424 }
425 
426 /*
427  * Find an IPv4 multicast source entry for this imo which matches
428  * the given group index for this socket, and source address.
429  *
430  * NOTE: This does not check if the entry is in-mode, merely if
431  * it exists, which may not be the desired behaviour.
432  */
433 static struct in_msource *
434 imo_match_source(struct in_mfilter *imf, const struct sockaddr *src)
435 {
436 	struct ip_msource	 find;
437 	struct ip_msource	*ims;
438 	const sockunion_t	*psa;
439 
440 	KASSERT(src->sa_family == AF_INET, ("%s: !AF_INET", __func__));
441 
442 	/* Source trees are keyed in host byte order. */
443 	psa = (const sockunion_t *)src;
444 	find.ims_haddr = ntohl(psa->sin.sin_addr.s_addr);
445 	ims = RB_FIND(ip_msource_tree, &imf->imf_sources, &find);
446 
447 	return ((struct in_msource *)ims);
448 }
449 
450 /*
451  * Perform filtering for multicast datagrams on a socket by group and source.
452  *
453  * Returns 0 if a datagram should be allowed through, or various error codes
454  * if the socket was not a member of the group, or the source was muted, etc.
455  */
456 int
457 imo_multi_filter(const struct ip_moptions *imo, const struct ifnet *ifp,
458     const struct sockaddr *group, const struct sockaddr *src)
459 {
460 	struct in_mfilter *imf;
461 	struct in_msource *ims;
462 	int mode;
463 
464 	KASSERT(ifp != NULL, ("%s: null ifp", __func__));
465 
466 	imf = imo_match_group(imo, ifp, group);
467 	if (imf == NULL)
468 		return (MCAST_NOTGMEMBER);
469 
470 	/*
471 	 * Check if the source was included in an (S,G) join.
472 	 * Allow reception on exclusive memberships by default,
473 	 * reject reception on inclusive memberships by default.
474 	 * Exclude source only if an in-mode exclude filter exists.
475 	 * Include source only if an in-mode include filter exists.
476 	 * NOTE: We are comparing group state here at IGMP t1 (now)
477 	 * with socket-layer t0 (since last downcall).
478 	 */
479 	mode = imf->imf_st[1];
480 	ims = imo_match_source(imf, src);
481 
482 	if ((ims == NULL && mode == MCAST_INCLUDE) ||
483 	    (ims != NULL && ims->imsl_st[0] == MCAST_EXCLUDE))
484 		return (MCAST_NOTSMEMBER);
485 
486 	return (MCAST_PASS);
487 }
488 
489 /*
490  * Find and return a reference to an in_multi record for (ifp, group),
491  * and bump its reference count.
492  * If one does not exist, try to allocate it, and update link-layer multicast
493  * filters on ifp to listen for group.
494  * Assumes the IN_MULTI lock is held across the call.
495  * Return 0 if successful, otherwise return an appropriate error code.
496  */
497 static int
498 in_getmulti(struct ifnet *ifp, const struct in_addr *group,
499     struct in_multi **pinm)
500 {
501 	struct sockaddr_in	 gsin;
502 	struct ifmultiaddr	*ifma;
503 	struct in_ifinfo	*ii;
504 	struct in_multi		*inm;
505 	int error;
506 
507 	IN_MULTI_LOCK_ASSERT();
508 
509 	ii = (struct in_ifinfo *)ifp->if_afdata[AF_INET];
510 	IN_MULTI_LIST_LOCK();
511 	inm = inm_lookup(ifp, *group);
512 	if (inm != NULL) {
513 		/*
514 		 * If we already joined this group, just bump the
515 		 * refcount and return it.
516 		 */
517 		KASSERT(inm->inm_refcount >= 1,
518 		    ("%s: bad refcount %d", __func__, inm->inm_refcount));
519 		inm_acquire_locked(inm);
520 		*pinm = inm;
521 	}
522 	IN_MULTI_LIST_UNLOCK();
523 	if (inm != NULL)
524 		return (0);
525 
526 	memset(&gsin, 0, sizeof(gsin));
527 	gsin.sin_family = AF_INET;
528 	gsin.sin_len = sizeof(struct sockaddr_in);
529 	gsin.sin_addr = *group;
530 
531 	/*
532 	 * Check if a link-layer group is already associated
533 	 * with this network-layer group on the given ifnet.
534 	 */
535 	error = if_addmulti(ifp, (struct sockaddr *)&gsin, &ifma);
536 	if (error != 0)
537 		return (error);
538 
539 	/* XXX ifma_protospec must be covered by IF_ADDR_LOCK */
540 	IN_MULTI_LIST_LOCK();
541 	IF_ADDR_WLOCK(ifp);
542 
543 	/*
544 	 * If something other than netinet is occupying the link-layer
545 	 * group, print a meaningful error message and back out of
546 	 * the allocation.
547 	 * Otherwise, bump the refcount on the existing network-layer
548 	 * group association and return it.
549 	 */
550 	if (ifma->ifma_protospec != NULL) {
551 		inm = (struct in_multi *)ifma->ifma_protospec;
552 #ifdef INVARIANTS
553 		KASSERT(ifma->ifma_addr != NULL, ("%s: no ifma_addr",
554 		    __func__));
555 		KASSERT(ifma->ifma_addr->sa_family == AF_INET,
556 		    ("%s: ifma not AF_INET", __func__));
557 		KASSERT(inm != NULL, ("%s: no ifma_protospec", __func__));
558 		if (inm->inm_ifma != ifma || inm->inm_ifp != ifp ||
559 		    !in_hosteq(inm->inm_addr, *group)) {
560 			char addrbuf[INET_ADDRSTRLEN];
561 
562 			panic("%s: ifma %p is inconsistent with %p (%s)",
563 			    __func__, ifma, inm, inet_ntoa_r(*group, addrbuf));
564 		}
565 #endif
566 		inm_acquire_locked(inm);
567 		*pinm = inm;
568 		goto out_locked;
569 	}
570 
571 	IF_ADDR_WLOCK_ASSERT(ifp);
572 
573 	/*
574 	 * A new in_multi record is needed; allocate and initialize it.
575 	 * We DO NOT perform an IGMP join as the in_ layer may need to
576 	 * push an initial source list down to IGMP to support SSM.
577 	 *
578 	 * The initial source filter state is INCLUDE, {} as per the RFC.
579 	 */
580 	inm = malloc(sizeof(*inm), M_IPMADDR, M_NOWAIT | M_ZERO);
581 	if (inm == NULL) {
582 		IF_ADDR_WUNLOCK(ifp);
583 		IN_MULTI_LIST_UNLOCK();
584 		if_delmulti_ifma(ifma);
585 		return (ENOMEM);
586 	}
587 	inm->inm_addr = *group;
588 	inm->inm_ifp = ifp;
589 	inm->inm_igi = ii->ii_igmp;
590 	inm->inm_ifma = ifma;
591 	inm->inm_refcount = 1;
592 	inm->inm_state = IGMP_NOT_MEMBER;
593 	mbufq_init(&inm->inm_scq, IGMP_MAX_STATE_CHANGES);
594 	inm->inm_st[0].iss_fmode = MCAST_UNDEFINED;
595 	inm->inm_st[1].iss_fmode = MCAST_UNDEFINED;
596 	RB_INIT(&inm->inm_srcs);
597 
598 	ifma->ifma_protospec = inm;
599 
600 	*pinm = inm;
601  out_locked:
602 	IF_ADDR_WUNLOCK(ifp);
603 	IN_MULTI_LIST_UNLOCK();
604 	return (0);
605 }
606 
607 /*
608  * Drop a reference to an in_multi record.
609  *
610  * If the refcount drops to 0, free the in_multi record and
611  * delete the underlying link-layer membership.
612  */
613 static void
614 inm_release(struct in_multi *inm)
615 {
616 	struct ifmultiaddr *ifma;
617 	struct ifnet *ifp;
618 
619 	CTR2(KTR_IGMPV3, "%s: refcount is %d", __func__, inm->inm_refcount);
620 	MPASS(inm->inm_refcount == 0);
621 	CTR2(KTR_IGMPV3, "%s: freeing inm %p", __func__, inm);
622 
623 	ifma = inm->inm_ifma;
624 	ifp = inm->inm_ifp;
625 
626 	/* XXX this access is not covered by IF_ADDR_LOCK */
627 	CTR2(KTR_IGMPV3, "%s: purging ifma %p", __func__, ifma);
628 	if (ifp != NULL) {
629 		CURVNET_SET(ifp->if_vnet);
630 		inm_purge(inm);
631 		free(inm, M_IPMADDR);
632 		if_delmulti_ifma_flags(ifma, 1);
633 		CURVNET_RESTORE();
634 		if_rele(ifp);
635 	} else {
636 		inm_purge(inm);
637 		free(inm, M_IPMADDR);
638 		if_delmulti_ifma_flags(ifma, 1);
639 	}
640 }
641 
642 /*
643  * Clear recorded source entries for a group.
644  * Used by the IGMP code. Caller must hold the IN_MULTI lock.
645  * FIXME: Should reap.
646  */
647 void
648 inm_clear_recorded(struct in_multi *inm)
649 {
650 	struct ip_msource	*ims;
651 
652 	IN_MULTI_LIST_LOCK_ASSERT();
653 
654 	RB_FOREACH(ims, ip_msource_tree, &inm->inm_srcs) {
655 		if (ims->ims_stp) {
656 			ims->ims_stp = 0;
657 			--inm->inm_st[1].iss_rec;
658 		}
659 	}
660 	KASSERT(inm->inm_st[1].iss_rec == 0,
661 	    ("%s: iss_rec %d not 0", __func__, inm->inm_st[1].iss_rec));
662 }
663 
664 /*
665  * Record a source as pending for a Source-Group IGMPv3 query.
666  * This lives here as it modifies the shared tree.
667  *
668  * inm is the group descriptor.
669  * naddr is the address of the source to record in network-byte order.
670  *
671  * If the net.inet.igmp.sgalloc sysctl is non-zero, we will
672  * lazy-allocate a source node in response to an SG query.
673  * Otherwise, no allocation is performed. This saves some memory
674  * with the trade-off that the source will not be reported to the
675  * router if joined in the window between the query response and
676  * the group actually being joined on the local host.
677  *
678  * VIMAGE: XXX: Currently the igmp_sgalloc feature has been removed.
679  * This turns off the allocation of a recorded source entry if
680  * the group has not been joined.
681  *
682  * Return 0 if the source didn't exist or was already marked as recorded.
683  * Return 1 if the source was marked as recorded by this function.
684  * Return <0 if any error occurred (negated errno code).
685  */
686 int
687 inm_record_source(struct in_multi *inm, const in_addr_t naddr)
688 {
689 	struct ip_msource	 find;
690 	struct ip_msource	*ims, *nims;
691 
692 	IN_MULTI_LIST_LOCK_ASSERT();
693 
694 	find.ims_haddr = ntohl(naddr);
695 	ims = RB_FIND(ip_msource_tree, &inm->inm_srcs, &find);
696 	if (ims && ims->ims_stp)
697 		return (0);
698 	if (ims == NULL) {
699 		if (inm->inm_nsrc == in_mcast_maxgrpsrc)
700 			return (-ENOSPC);
701 		nims = malloc(sizeof(struct ip_msource), M_IPMSOURCE,
702 		    M_NOWAIT | M_ZERO);
703 		if (nims == NULL)
704 			return (-ENOMEM);
705 		nims->ims_haddr = find.ims_haddr;
706 		RB_INSERT(ip_msource_tree, &inm->inm_srcs, nims);
707 		++inm->inm_nsrc;
708 		ims = nims;
709 	}
710 
711 	/*
712 	 * Mark the source as recorded and update the recorded
713 	 * source count.
714 	 */
715 	++ims->ims_stp;
716 	++inm->inm_st[1].iss_rec;
717 
718 	return (1);
719 }
720 
721 /*
722  * Return a pointer to an in_msource owned by an in_mfilter,
723  * given its source address.
724  * Lazy-allocate if needed. If this is a new entry its filter state is
725  * undefined at t0.
726  *
727  * imf is the filter set being modified.
728  * haddr is the source address in *host* byte-order.
729  *
730  * SMPng: May be called with locks held; malloc must not block.
731  */
732 static int
733 imf_get_source(struct in_mfilter *imf, const struct sockaddr_in *psin,
734     struct in_msource **plims)
735 {
736 	struct ip_msource	 find;
737 	struct ip_msource	*ims, *nims;
738 	struct in_msource	*lims;
739 	int			 error;
740 
741 	error = 0;
742 	ims = NULL;
743 	lims = NULL;
744 
745 	/* key is host byte order */
746 	find.ims_haddr = ntohl(psin->sin_addr.s_addr);
747 	ims = RB_FIND(ip_msource_tree, &imf->imf_sources, &find);
748 	lims = (struct in_msource *)ims;
749 	if (lims == NULL) {
750 		if (imf->imf_nsrc == in_mcast_maxsocksrc)
751 			return (ENOSPC);
752 		nims = malloc(sizeof(struct in_msource), M_INMFILTER,
753 		    M_NOWAIT | M_ZERO);
754 		if (nims == NULL)
755 			return (ENOMEM);
756 		lims = (struct in_msource *)nims;
757 		lims->ims_haddr = find.ims_haddr;
758 		lims->imsl_st[0] = MCAST_UNDEFINED;
759 		RB_INSERT(ip_msource_tree, &imf->imf_sources, nims);
760 		++imf->imf_nsrc;
761 	}
762 
763 	*plims = lims;
764 
765 	return (error);
766 }
767 
768 /*
769  * Graft a source entry into an existing socket-layer filter set,
770  * maintaining any required invariants and checking allocations.
771  *
772  * The source is marked as being in the new filter mode at t1.
773  *
774  * Return the pointer to the new node, otherwise return NULL.
775  */
776 static struct in_msource *
777 imf_graft(struct in_mfilter *imf, const uint8_t st1,
778     const struct sockaddr_in *psin)
779 {
780 	struct ip_msource	*nims;
781 	struct in_msource	*lims;
782 
783 	nims = malloc(sizeof(struct in_msource), M_INMFILTER,
784 	    M_NOWAIT | M_ZERO);
785 	if (nims == NULL)
786 		return (NULL);
787 	lims = (struct in_msource *)nims;
788 	lims->ims_haddr = ntohl(psin->sin_addr.s_addr);
789 	lims->imsl_st[0] = MCAST_UNDEFINED;
790 	lims->imsl_st[1] = st1;
791 	RB_INSERT(ip_msource_tree, &imf->imf_sources, nims);
792 	++imf->imf_nsrc;
793 
794 	return (lims);
795 }
796 
797 /*
798  * Prune a source entry from an existing socket-layer filter set,
799  * maintaining any required invariants and checking allocations.
800  *
801  * The source is marked as being left at t1, it is not freed.
802  *
803  * Return 0 if no error occurred, otherwise return an errno value.
804  */
805 static int
806 imf_prune(struct in_mfilter *imf, const struct sockaddr_in *psin)
807 {
808 	struct ip_msource	 find;
809 	struct ip_msource	*ims;
810 	struct in_msource	*lims;
811 
812 	/* key is host byte order */
813 	find.ims_haddr = ntohl(psin->sin_addr.s_addr);
814 	ims = RB_FIND(ip_msource_tree, &imf->imf_sources, &find);
815 	if (ims == NULL)
816 		return (ENOENT);
817 	lims = (struct in_msource *)ims;
818 	lims->imsl_st[1] = MCAST_UNDEFINED;
819 	return (0);
820 }
821 
822 /*
823  * Revert socket-layer filter set deltas at t1 to t0 state.
824  */
825 static void
826 imf_rollback(struct in_mfilter *imf)
827 {
828 	struct ip_msource	*ims, *tims;
829 	struct in_msource	*lims;
830 
831 	RB_FOREACH_SAFE(ims, ip_msource_tree, &imf->imf_sources, tims) {
832 		lims = (struct in_msource *)ims;
833 		if (lims->imsl_st[0] == lims->imsl_st[1]) {
834 			/* no change at t1 */
835 			continue;
836 		} else if (lims->imsl_st[0] != MCAST_UNDEFINED) {
837 			/* revert change to existing source at t1 */
838 			lims->imsl_st[1] = lims->imsl_st[0];
839 		} else {
840 			/* revert source added t1 */
841 			CTR2(KTR_IGMPV3, "%s: free ims %p", __func__, ims);
842 			RB_REMOVE(ip_msource_tree, &imf->imf_sources, ims);
843 			free(ims, M_INMFILTER);
844 			imf->imf_nsrc--;
845 		}
846 	}
847 	imf->imf_st[1] = imf->imf_st[0];
848 }
849 
850 /*
851  * Mark socket-layer filter set as INCLUDE {} at t1.
852  */
853 static void
854 imf_leave(struct in_mfilter *imf)
855 {
856 	struct ip_msource	*ims;
857 	struct in_msource	*lims;
858 
859 	RB_FOREACH(ims, ip_msource_tree, &imf->imf_sources) {
860 		lims = (struct in_msource *)ims;
861 		lims->imsl_st[1] = MCAST_UNDEFINED;
862 	}
863 	imf->imf_st[1] = MCAST_INCLUDE;
864 }
865 
866 /*
867  * Mark socket-layer filter set deltas as committed.
868  */
869 static void
870 imf_commit(struct in_mfilter *imf)
871 {
872 	struct ip_msource	*ims;
873 	struct in_msource	*lims;
874 
875 	RB_FOREACH(ims, ip_msource_tree, &imf->imf_sources) {
876 		lims = (struct in_msource *)ims;
877 		lims->imsl_st[0] = lims->imsl_st[1];
878 	}
879 	imf->imf_st[0] = imf->imf_st[1];
880 }
881 
882 /*
883  * Reap unreferenced sources from socket-layer filter set.
884  */
885 static void
886 imf_reap(struct in_mfilter *imf)
887 {
888 	struct ip_msource	*ims, *tims;
889 	struct in_msource	*lims;
890 
891 	RB_FOREACH_SAFE(ims, ip_msource_tree, &imf->imf_sources, tims) {
892 		lims = (struct in_msource *)ims;
893 		if ((lims->imsl_st[0] == MCAST_UNDEFINED) &&
894 		    (lims->imsl_st[1] == MCAST_UNDEFINED)) {
895 			CTR2(KTR_IGMPV3, "%s: free lims %p", __func__, ims);
896 			RB_REMOVE(ip_msource_tree, &imf->imf_sources, ims);
897 			free(ims, M_INMFILTER);
898 			imf->imf_nsrc--;
899 		}
900 	}
901 }
902 
903 /*
904  * Purge socket-layer filter set.
905  */
906 static void
907 imf_purge(struct in_mfilter *imf)
908 {
909 	struct ip_msource	*ims, *tims;
910 
911 	RB_FOREACH_SAFE(ims, ip_msource_tree, &imf->imf_sources, tims) {
912 		CTR2(KTR_IGMPV3, "%s: free ims %p", __func__, ims);
913 		RB_REMOVE(ip_msource_tree, &imf->imf_sources, ims);
914 		free(ims, M_INMFILTER);
915 		imf->imf_nsrc--;
916 	}
917 	imf->imf_st[0] = imf->imf_st[1] = MCAST_UNDEFINED;
918 	KASSERT(RB_EMPTY(&imf->imf_sources),
919 	    ("%s: imf_sources not empty", __func__));
920 }
921 
922 /*
923  * Look up a source filter entry for a multicast group.
924  *
925  * inm is the group descriptor to work with.
926  * haddr is the host-byte-order IPv4 address to look up.
927  * noalloc may be non-zero to suppress allocation of sources.
928  * *pims will be set to the address of the retrieved or allocated source.
929  *
930  * SMPng: NOTE: may be called with locks held.
931  * Return 0 if successful, otherwise return a non-zero error code.
932  */
933 static int
934 inm_get_source(struct in_multi *inm, const in_addr_t haddr,
935     const int noalloc, struct ip_msource **pims)
936 {
937 	struct ip_msource	 find;
938 	struct ip_msource	*ims, *nims;
939 
940 	find.ims_haddr = haddr;
941 	ims = RB_FIND(ip_msource_tree, &inm->inm_srcs, &find);
942 	if (ims == NULL && !noalloc) {
943 		if (inm->inm_nsrc == in_mcast_maxgrpsrc)
944 			return (ENOSPC);
945 		nims = malloc(sizeof(struct ip_msource), M_IPMSOURCE,
946 		    M_NOWAIT | M_ZERO);
947 		if (nims == NULL)
948 			return (ENOMEM);
949 		nims->ims_haddr = haddr;
950 		RB_INSERT(ip_msource_tree, &inm->inm_srcs, nims);
951 		++inm->inm_nsrc;
952 		ims = nims;
953 #ifdef KTR
954 		CTR3(KTR_IGMPV3, "%s: allocated 0x%08x as %p", __func__,
955 		    haddr, ims);
956 #endif
957 	}
958 
959 	*pims = ims;
960 	return (0);
961 }
962 
963 /*
964  * Merge socket-layer source into IGMP-layer source.
965  * If rollback is non-zero, perform the inverse of the merge.
966  */
967 static void
968 ims_merge(struct ip_msource *ims, const struct in_msource *lims,
969     const int rollback)
970 {
971 	int n = rollback ? -1 : 1;
972 
973 	if (lims->imsl_st[0] == MCAST_EXCLUDE) {
974 		CTR3(KTR_IGMPV3, "%s: t1 ex -= %d on 0x%08x",
975 		    __func__, n, ims->ims_haddr);
976 		ims->ims_st[1].ex -= n;
977 	} else if (lims->imsl_st[0] == MCAST_INCLUDE) {
978 		CTR3(KTR_IGMPV3, "%s: t1 in -= %d on 0x%08x",
979 		    __func__, n, ims->ims_haddr);
980 		ims->ims_st[1].in -= n;
981 	}
982 
983 	if (lims->imsl_st[1] == MCAST_EXCLUDE) {
984 		CTR3(KTR_IGMPV3, "%s: t1 ex += %d on 0x%08x",
985 		    __func__, n, ims->ims_haddr);
986 		ims->ims_st[1].ex += n;
987 	} else if (lims->imsl_st[1] == MCAST_INCLUDE) {
988 		CTR3(KTR_IGMPV3, "%s: t1 in += %d on 0x%08x",
989 		    __func__, n, ims->ims_haddr);
990 		ims->ims_st[1].in += n;
991 	}
992 }
993 
994 /*
995  * Atomically update the global in_multi state, when a membership's
996  * filter list is being updated in any way.
997  *
998  * imf is the per-inpcb-membership group filter pointer.
999  * A fake imf may be passed for in-kernel consumers.
1000  *
1001  * XXX This is a candidate for a set-symmetric-difference style loop
1002  * which would eliminate the repeated lookup from root of ims nodes,
1003  * as they share the same key space.
1004  *
1005  * If any error occurred this function will back out of refcounts
1006  * and return a non-zero value.
1007  */
1008 static int
1009 inm_merge(struct in_multi *inm, /*const*/ struct in_mfilter *imf)
1010 {
1011 	struct ip_msource	*ims, *nims;
1012 	struct in_msource	*lims;
1013 	int			 schanged, error;
1014 	int			 nsrc0, nsrc1;
1015 
1016 	schanged = 0;
1017 	error = 0;
1018 	nsrc1 = nsrc0 = 0;
1019 	IN_MULTI_LIST_LOCK_ASSERT();
1020 
1021 	/*
1022 	 * Update the source filters first, as this may fail.
1023 	 * Maintain count of in-mode filters at t0, t1. These are
1024 	 * used to work out if we transition into ASM mode or not.
1025 	 * Maintain a count of source filters whose state was
1026 	 * actually modified by this operation.
1027 	 */
1028 	RB_FOREACH(ims, ip_msource_tree, &imf->imf_sources) {
1029 		lims = (struct in_msource *)ims;
1030 		if (lims->imsl_st[0] == imf->imf_st[0]) nsrc0++;
1031 		if (lims->imsl_st[1] == imf->imf_st[1]) nsrc1++;
1032 		if (lims->imsl_st[0] == lims->imsl_st[1]) continue;
1033 		error = inm_get_source(inm, lims->ims_haddr, 0, &nims);
1034 		++schanged;
1035 		if (error)
1036 			break;
1037 		ims_merge(nims, lims, 0);
1038 	}
1039 	if (error) {
1040 		struct ip_msource *bims;
1041 
1042 		RB_FOREACH_REVERSE_FROM(ims, ip_msource_tree, nims) {
1043 			lims = (struct in_msource *)ims;
1044 			if (lims->imsl_st[0] == lims->imsl_st[1])
1045 				continue;
1046 			(void)inm_get_source(inm, lims->ims_haddr, 1, &bims);
1047 			if (bims == NULL)
1048 				continue;
1049 			ims_merge(bims, lims, 1);
1050 		}
1051 		goto out_reap;
1052 	}
1053 
1054 	CTR3(KTR_IGMPV3, "%s: imf filters in-mode: %d at t0, %d at t1",
1055 	    __func__, nsrc0, nsrc1);
1056 
1057 	/* Handle transition between INCLUDE {n} and INCLUDE {} on socket. */
1058 	if (imf->imf_st[0] == imf->imf_st[1] &&
1059 	    imf->imf_st[1] == MCAST_INCLUDE) {
1060 		if (nsrc1 == 0) {
1061 			CTR1(KTR_IGMPV3, "%s: --in on inm at t1", __func__);
1062 			--inm->inm_st[1].iss_in;
1063 		}
1064 	}
1065 
1066 	/* Handle filter mode transition on socket. */
1067 	if (imf->imf_st[0] != imf->imf_st[1]) {
1068 		CTR3(KTR_IGMPV3, "%s: imf transition %d to %d",
1069 		    __func__, imf->imf_st[0], imf->imf_st[1]);
1070 
1071 		if (imf->imf_st[0] == MCAST_EXCLUDE) {
1072 			CTR1(KTR_IGMPV3, "%s: --ex on inm at t1", __func__);
1073 			--inm->inm_st[1].iss_ex;
1074 		} else if (imf->imf_st[0] == MCAST_INCLUDE) {
1075 			CTR1(KTR_IGMPV3, "%s: --in on inm at t1", __func__);
1076 			--inm->inm_st[1].iss_in;
1077 		}
1078 
1079 		if (imf->imf_st[1] == MCAST_EXCLUDE) {
1080 			CTR1(KTR_IGMPV3, "%s: ex++ on inm at t1", __func__);
1081 			inm->inm_st[1].iss_ex++;
1082 		} else if (imf->imf_st[1] == MCAST_INCLUDE && nsrc1 > 0) {
1083 			CTR1(KTR_IGMPV3, "%s: in++ on inm at t1", __func__);
1084 			inm->inm_st[1].iss_in++;
1085 		}
1086 	}
1087 
1088 	/*
1089 	 * Track inm filter state in terms of listener counts.
1090 	 * If there are any exclusive listeners, stack-wide
1091 	 * membership is exclusive.
1092 	 * Otherwise, if only inclusive listeners, stack-wide is inclusive.
1093 	 * If no listeners remain, state is undefined at t1,
1094 	 * and the IGMP lifecycle for this group should finish.
1095 	 */
1096 	if (inm->inm_st[1].iss_ex > 0) {
1097 		CTR1(KTR_IGMPV3, "%s: transition to EX", __func__);
1098 		inm->inm_st[1].iss_fmode = MCAST_EXCLUDE;
1099 	} else if (inm->inm_st[1].iss_in > 0) {
1100 		CTR1(KTR_IGMPV3, "%s: transition to IN", __func__);
1101 		inm->inm_st[1].iss_fmode = MCAST_INCLUDE;
1102 	} else {
1103 		CTR1(KTR_IGMPV3, "%s: transition to UNDEF", __func__);
1104 		inm->inm_st[1].iss_fmode = MCAST_UNDEFINED;
1105 	}
1106 
1107 	/* Decrement ASM listener count on transition out of ASM mode. */
1108 	if (imf->imf_st[0] == MCAST_EXCLUDE && nsrc0 == 0) {
1109 		if ((imf->imf_st[1] != MCAST_EXCLUDE) ||
1110 		    (imf->imf_st[1] == MCAST_EXCLUDE && nsrc1 > 0)) {
1111 			CTR1(KTR_IGMPV3, "%s: --asm on inm at t1", __func__);
1112 			--inm->inm_st[1].iss_asm;
1113 		}
1114 	}
1115 
1116 	/* Increment ASM listener count on transition to ASM mode. */
1117 	if (imf->imf_st[1] == MCAST_EXCLUDE && nsrc1 == 0) {
1118 		CTR1(KTR_IGMPV3, "%s: asm++ on inm at t1", __func__);
1119 		inm->inm_st[1].iss_asm++;
1120 	}
1121 
1122 	CTR3(KTR_IGMPV3, "%s: merged imf %p to inm %p", __func__, imf, inm);
1123 	inm_print(inm);
1124 
1125 out_reap:
1126 	if (schanged > 0) {
1127 		CTR1(KTR_IGMPV3, "%s: sources changed; reaping", __func__);
1128 		inm_reap(inm);
1129 	}
1130 	return (error);
1131 }
1132 
1133 /*
1134  * Mark an in_multi's filter set deltas as committed.
1135  * Called by IGMP after a state change has been enqueued.
1136  */
1137 void
1138 inm_commit(struct in_multi *inm)
1139 {
1140 	struct ip_msource	*ims;
1141 
1142 	CTR2(KTR_IGMPV3, "%s: commit inm %p", __func__, inm);
1143 	CTR1(KTR_IGMPV3, "%s: pre commit:", __func__);
1144 	inm_print(inm);
1145 
1146 	RB_FOREACH(ims, ip_msource_tree, &inm->inm_srcs) {
1147 		ims->ims_st[0] = ims->ims_st[1];
1148 	}
1149 	inm->inm_st[0] = inm->inm_st[1];
1150 }
1151 
1152 /*
1153  * Reap unreferenced nodes from an in_multi's filter set.
1154  */
1155 static void
1156 inm_reap(struct in_multi *inm)
1157 {
1158 	struct ip_msource	*ims, *tims;
1159 
1160 	RB_FOREACH_SAFE(ims, ip_msource_tree, &inm->inm_srcs, tims) {
1161 		if (ims->ims_st[0].ex > 0 || ims->ims_st[0].in > 0 ||
1162 		    ims->ims_st[1].ex > 0 || ims->ims_st[1].in > 0 ||
1163 		    ims->ims_stp != 0)
1164 			continue;
1165 		CTR2(KTR_IGMPV3, "%s: free ims %p", __func__, ims);
1166 		RB_REMOVE(ip_msource_tree, &inm->inm_srcs, ims);
1167 		free(ims, M_IPMSOURCE);
1168 		inm->inm_nsrc--;
1169 	}
1170 }
1171 
1172 /*
1173  * Purge all source nodes from an in_multi's filter set.
1174  */
1175 static void
1176 inm_purge(struct in_multi *inm)
1177 {
1178 	struct ip_msource	*ims, *tims;
1179 
1180 	RB_FOREACH_SAFE(ims, ip_msource_tree, &inm->inm_srcs, tims) {
1181 		CTR2(KTR_IGMPV3, "%s: free ims %p", __func__, ims);
1182 		RB_REMOVE(ip_msource_tree, &inm->inm_srcs, ims);
1183 		free(ims, M_IPMSOURCE);
1184 		inm->inm_nsrc--;
1185 	}
1186 }
1187 
1188 /*
1189  * Join a multicast group; unlocked entry point.
1190  *
1191  * SMPng: XXX: in_joingroup() is called from in_control() when Giant
1192  * is not held. Fortunately, ifp is unlikely to have been detached
1193  * at this point, so we assume it's OK to recurse.
1194  */
1195 int
1196 in_joingroup(struct ifnet *ifp, const struct in_addr *gina,
1197     /*const*/ struct in_mfilter *imf, struct in_multi **pinm)
1198 {
1199 	int error;
1200 
1201 	IN_MULTI_LOCK();
1202 	error = in_joingroup_locked(ifp, gina, imf, pinm);
1203 	IN_MULTI_UNLOCK();
1204 
1205 	return (error);
1206 }
1207 
1208 /*
1209  * Join a multicast group; real entry point.
1210  *
1211  * Only preserves atomicity at inm level.
1212  * NOTE: imf argument cannot be const due to sys/tree.h limitations.
1213  *
1214  * If the IGMP downcall fails, the group is not joined, and an error
1215  * code is returned.
1216  */
1217 int
1218 in_joingroup_locked(struct ifnet *ifp, const struct in_addr *gina,
1219     /*const*/ struct in_mfilter *imf, struct in_multi **pinm)
1220 {
1221 	struct in_mfilter	 timf;
1222 	struct in_multi		*inm;
1223 	int			 error;
1224 
1225 	IN_MULTI_LOCK_ASSERT();
1226 	IN_MULTI_LIST_UNLOCK_ASSERT();
1227 
1228 	CTR4(KTR_IGMPV3, "%s: join 0x%08x on %p(%s))", __func__,
1229 	    ntohl(gina->s_addr), ifp, ifp->if_xname);
1230 
1231 	error = 0;
1232 	inm = NULL;
1233 
1234 	/*
1235 	 * If no imf was specified (i.e. kernel consumer),
1236 	 * fake one up and assume it is an ASM join.
1237 	 */
1238 	if (imf == NULL) {
1239 		imf_init(&timf, MCAST_UNDEFINED, MCAST_EXCLUDE);
1240 		imf = &timf;
1241 	}
1242 
1243 	error = in_getmulti(ifp, gina, &inm);
1244 	if (error) {
1245 		CTR1(KTR_IGMPV3, "%s: in_getmulti() failure", __func__);
1246 		return (error);
1247 	}
1248 	IN_MULTI_LIST_LOCK();
1249 	CTR1(KTR_IGMPV3, "%s: merge inm state", __func__);
1250 	error = inm_merge(inm, imf);
1251 	if (error) {
1252 		CTR1(KTR_IGMPV3, "%s: failed to merge inm state", __func__);
1253 		goto out_inm_release;
1254 	}
1255 
1256 	CTR1(KTR_IGMPV3, "%s: doing igmp downcall", __func__);
1257 	error = igmp_change_state(inm);
1258 	if (error) {
1259 		CTR1(KTR_IGMPV3, "%s: failed to update source", __func__);
1260 		goto out_inm_release;
1261 	}
1262 
1263  out_inm_release:
1264 	if (error) {
1265 		CTR2(KTR_IGMPV3, "%s: dropping ref on %p", __func__, inm);
1266 		IF_ADDR_WLOCK(ifp);
1267 		inm_release_deferred(inm);
1268 		IF_ADDR_WUNLOCK(ifp);
1269 	} else {
1270 		*pinm = inm;
1271 	}
1272 	IN_MULTI_LIST_UNLOCK();
1273 
1274 	return (error);
1275 }
1276 
1277 /*
1278  * Leave a multicast group; unlocked entry point.
1279  */
1280 int
1281 in_leavegroup(struct in_multi *inm, /*const*/ struct in_mfilter *imf)
1282 {
1283 	int error;
1284 
1285 	IN_MULTI_LOCK();
1286 	error = in_leavegroup_locked(inm, imf);
1287 	IN_MULTI_UNLOCK();
1288 
1289 	return (error);
1290 }
1291 
1292 /*
1293  * Leave a multicast group; real entry point.
1294  * All source filters will be expunged.
1295  *
1296  * Only preserves atomicity at inm level.
1297  *
1298  * Holding the write lock for the INP which contains imf
1299  * is highly advisable. We can't assert for it as imf does not
1300  * contain a back-pointer to the owning inp.
1301  *
1302  * Note: This is not the same as inm_release(*) as this function also
1303  * makes a state change downcall into IGMP.
1304  */
1305 int
1306 in_leavegroup_locked(struct in_multi *inm, /*const*/ struct in_mfilter *imf)
1307 {
1308 	struct in_mfilter	 timf;
1309 	int			 error;
1310 
1311 	IN_MULTI_LOCK_ASSERT();
1312 	IN_MULTI_LIST_UNLOCK_ASSERT();
1313 
1314 	error = 0;
1315 
1316 	CTR5(KTR_IGMPV3, "%s: leave inm %p, 0x%08x/%s, imf %p", __func__,
1317 	    inm, ntohl(inm->inm_addr.s_addr),
1318 	    (inm_is_ifp_detached(inm) ? "null" : inm->inm_ifp->if_xname),
1319 	    imf);
1320 
1321 	/*
1322 	 * If no imf was specified (i.e. kernel consumer),
1323 	 * fake one up and assume it is an ASM join.
1324 	 */
1325 	if (imf == NULL) {
1326 		imf_init(&timf, MCAST_EXCLUDE, MCAST_UNDEFINED);
1327 		imf = &timf;
1328 	}
1329 
1330 	/*
1331 	 * Begin state merge transaction at IGMP layer.
1332 	 *
1333 	 * As this particular invocation should not cause any memory
1334 	 * to be allocated, and there is no opportunity to roll back
1335 	 * the transaction, it MUST NOT fail.
1336 	 */
1337 	CTR1(KTR_IGMPV3, "%s: merge inm state", __func__);
1338 	IN_MULTI_LIST_LOCK();
1339 	error = inm_merge(inm, imf);
1340 	KASSERT(error == 0, ("%s: failed to merge inm state", __func__));
1341 
1342 	CTR1(KTR_IGMPV3, "%s: doing igmp downcall", __func__);
1343 	CURVNET_SET(inm->inm_ifp->if_vnet);
1344 	error = igmp_change_state(inm);
1345 	IF_ADDR_WLOCK(inm->inm_ifp);
1346 	inm_release_deferred(inm);
1347 	IF_ADDR_WUNLOCK(inm->inm_ifp);
1348 	IN_MULTI_LIST_UNLOCK();
1349 	CURVNET_RESTORE();
1350 	if (error)
1351 		CTR1(KTR_IGMPV3, "%s: failed igmp downcall", __func__);
1352 
1353 	CTR2(KTR_IGMPV3, "%s: dropping ref on %p", __func__, inm);
1354 
1355 	return (error);
1356 }
1357 
1358 /*#ifndef BURN_BRIDGES*/
1359 
1360 /*
1361  * Block or unblock an ASM multicast source on an inpcb.
1362  * This implements the delta-based API described in RFC 3678.
1363  *
1364  * The delta-based API applies only to exclusive-mode memberships.
1365  * An IGMP downcall will be performed.
1366  *
1367  * SMPng: NOTE: Must take Giant as a join may create a new ifma.
1368  *
1369  * Return 0 if successful, otherwise return an appropriate error code.
1370  */
1371 static int
1372 inp_block_unblock_source(struct inpcb *inp, struct sockopt *sopt)
1373 {
1374 	struct epoch_tracker		 et;
1375 	struct group_source_req		 gsr;
1376 	sockunion_t			*gsa, *ssa;
1377 	struct ifnet			*ifp;
1378 	struct in_mfilter		*imf;
1379 	struct ip_moptions		*imo;
1380 	struct in_msource		*ims;
1381 	struct in_multi			*inm;
1382 	uint16_t			 fmode;
1383 	int				 error, doblock;
1384 
1385 	ifp = NULL;
1386 	error = 0;
1387 	doblock = 0;
1388 
1389 	memset(&gsr, 0, sizeof(struct group_source_req));
1390 	gsa = (sockunion_t *)&gsr.gsr_group;
1391 	ssa = (sockunion_t *)&gsr.gsr_source;
1392 
1393 	switch (sopt->sopt_name) {
1394 	case IP_BLOCK_SOURCE:
1395 	case IP_UNBLOCK_SOURCE: {
1396 		struct ip_mreq_source	 mreqs;
1397 
1398 		error = sooptcopyin(sopt, &mreqs,
1399 		    sizeof(struct ip_mreq_source),
1400 		    sizeof(struct ip_mreq_source));
1401 		if (error)
1402 			return (error);
1403 
1404 		gsa->sin.sin_family = AF_INET;
1405 		gsa->sin.sin_len = sizeof(struct sockaddr_in);
1406 		gsa->sin.sin_addr = mreqs.imr_multiaddr;
1407 
1408 		ssa->sin.sin_family = AF_INET;
1409 		ssa->sin.sin_len = sizeof(struct sockaddr_in);
1410 		ssa->sin.sin_addr = mreqs.imr_sourceaddr;
1411 
1412 		if (!in_nullhost(mreqs.imr_interface)) {
1413 			NET_EPOCH_ENTER(et);
1414 			INADDR_TO_IFP(mreqs.imr_interface, ifp);
1415 			/* XXXGL: ifref? */
1416 			NET_EPOCH_EXIT(et);
1417 		}
1418 		if (sopt->sopt_name == IP_BLOCK_SOURCE)
1419 			doblock = 1;
1420 
1421 		CTR3(KTR_IGMPV3, "%s: imr_interface = 0x%08x, ifp = %p",
1422 		    __func__, ntohl(mreqs.imr_interface.s_addr), ifp);
1423 		break;
1424 	    }
1425 
1426 	case MCAST_BLOCK_SOURCE:
1427 	case MCAST_UNBLOCK_SOURCE:
1428 		error = sooptcopyin(sopt, &gsr,
1429 		    sizeof(struct group_source_req),
1430 		    sizeof(struct group_source_req));
1431 		if (error)
1432 			return (error);
1433 
1434 		if (gsa->sin.sin_family != AF_INET ||
1435 		    gsa->sin.sin_len != sizeof(struct sockaddr_in))
1436 			return (EINVAL);
1437 
1438 		if (ssa->sin.sin_family != AF_INET ||
1439 		    ssa->sin.sin_len != sizeof(struct sockaddr_in))
1440 			return (EINVAL);
1441 
1442 		NET_EPOCH_ENTER(et);
1443 		ifp = ifnet_byindex(gsr.gsr_interface);
1444 		NET_EPOCH_EXIT(et);
1445 		if (ifp == NULL)
1446 			return (EADDRNOTAVAIL);
1447 
1448 		if (sopt->sopt_name == MCAST_BLOCK_SOURCE)
1449 			doblock = 1;
1450 		break;
1451 
1452 	default:
1453 		CTR2(KTR_IGMPV3, "%s: unknown sopt_name %d",
1454 		    __func__, sopt->sopt_name);
1455 		return (EOPNOTSUPP);
1456 		break;
1457 	}
1458 
1459 	if (!IN_MULTICAST(ntohl(gsa->sin.sin_addr.s_addr)))
1460 		return (EINVAL);
1461 
1462 	IN_MULTI_LOCK();
1463 
1464 	/*
1465 	 * Check if we are actually a member of this group.
1466 	 */
1467 	imo = inp_findmoptions(inp);
1468 	imf = imo_match_group(imo, ifp, &gsa->sa);
1469 	if (imf == NULL) {
1470 		error = EADDRNOTAVAIL;
1471 		goto out_inp_locked;
1472 	}
1473 	inm = imf->imf_inm;
1474 
1475 	/*
1476 	 * Attempting to use the delta-based API on an
1477 	 * non exclusive-mode membership is an error.
1478 	 */
1479 	fmode = imf->imf_st[0];
1480 	if (fmode != MCAST_EXCLUDE) {
1481 		error = EINVAL;
1482 		goto out_inp_locked;
1483 	}
1484 
1485 	/*
1486 	 * Deal with error cases up-front:
1487 	 *  Asked to block, but already blocked; or
1488 	 *  Asked to unblock, but nothing to unblock.
1489 	 * If adding a new block entry, allocate it.
1490 	 */
1491 	ims = imo_match_source(imf, &ssa->sa);
1492 	if ((ims != NULL && doblock) || (ims == NULL && !doblock)) {
1493 		CTR3(KTR_IGMPV3, "%s: source 0x%08x %spresent", __func__,
1494 		    ntohl(ssa->sin.sin_addr.s_addr), doblock ? "" : "not ");
1495 		error = EADDRNOTAVAIL;
1496 		goto out_inp_locked;
1497 	}
1498 
1499 	INP_WLOCK_ASSERT(inp);
1500 
1501 	/*
1502 	 * Begin state merge transaction at socket layer.
1503 	 */
1504 	if (doblock) {
1505 		CTR2(KTR_IGMPV3, "%s: %s source", __func__, "block");
1506 		ims = imf_graft(imf, fmode, &ssa->sin);
1507 		if (ims == NULL)
1508 			error = ENOMEM;
1509 	} else {
1510 		CTR2(KTR_IGMPV3, "%s: %s source", __func__, "allow");
1511 		error = imf_prune(imf, &ssa->sin);
1512 	}
1513 
1514 	if (error) {
1515 		CTR1(KTR_IGMPV3, "%s: merge imf state failed", __func__);
1516 		goto out_imf_rollback;
1517 	}
1518 
1519 	/*
1520 	 * Begin state merge transaction at IGMP layer.
1521 	 */
1522 	CTR1(KTR_IGMPV3, "%s: merge inm state", __func__);
1523 	IN_MULTI_LIST_LOCK();
1524 	error = inm_merge(inm, imf);
1525 	if (error) {
1526 		CTR1(KTR_IGMPV3, "%s: failed to merge inm state", __func__);
1527 		IN_MULTI_LIST_UNLOCK();
1528 		goto out_imf_rollback;
1529 	}
1530 
1531 	CTR1(KTR_IGMPV3, "%s: doing igmp downcall", __func__);
1532 	error = igmp_change_state(inm);
1533 	IN_MULTI_LIST_UNLOCK();
1534 	if (error)
1535 		CTR1(KTR_IGMPV3, "%s: failed igmp downcall", __func__);
1536 
1537 out_imf_rollback:
1538 	if (error)
1539 		imf_rollback(imf);
1540 	else
1541 		imf_commit(imf);
1542 
1543 	imf_reap(imf);
1544 
1545 out_inp_locked:
1546 	INP_WUNLOCK(inp);
1547 	IN_MULTI_UNLOCK();
1548 	return (error);
1549 }
1550 
1551 /*
1552  * Given an inpcb, return its multicast options structure pointer.  Accepts
1553  * an unlocked inpcb pointer, but will return it locked.  May sleep.
1554  *
1555  * SMPng: NOTE: Potentially calls malloc(M_WAITOK) with Giant held.
1556  * SMPng: NOTE: Returns with the INP write lock held.
1557  */
1558 static struct ip_moptions *
1559 inp_findmoptions(struct inpcb *inp)
1560 {
1561 	struct ip_moptions	 *imo;
1562 
1563 	INP_WLOCK(inp);
1564 	if (inp->inp_moptions != NULL)
1565 		return (inp->inp_moptions);
1566 
1567 	INP_WUNLOCK(inp);
1568 
1569 	imo = malloc(sizeof(*imo), M_IPMOPTS, M_WAITOK);
1570 
1571 	imo->imo_multicast_ifp = NULL;
1572 	imo->imo_multicast_addr.s_addr = INADDR_ANY;
1573 	imo->imo_multicast_vif = -1;
1574 	imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL;
1575 	imo->imo_multicast_loop = in_mcast_loop;
1576 	STAILQ_INIT(&imo->imo_head);
1577 
1578 	INP_WLOCK(inp);
1579 	if (inp->inp_moptions != NULL) {
1580 		free(imo, M_IPMOPTS);
1581 		return (inp->inp_moptions);
1582 	}
1583 	inp->inp_moptions = imo;
1584 	return (imo);
1585 }
1586 
1587 void
1588 inp_freemoptions(struct ip_moptions *imo)
1589 {
1590 	struct in_mfilter *imf;
1591 	struct in_multi *inm;
1592 	struct ifnet *ifp;
1593 
1594 	if (imo == NULL)
1595 		return;
1596 
1597 	while ((imf = ip_mfilter_first(&imo->imo_head)) != NULL) {
1598 		ip_mfilter_remove(&imo->imo_head, imf);
1599 
1600 		imf_leave(imf);
1601 		if ((inm = imf->imf_inm) != NULL) {
1602 			if ((ifp = inm->inm_ifp) != NULL) {
1603 				CURVNET_SET(ifp->if_vnet);
1604 				(void)in_leavegroup(inm, imf);
1605 				CURVNET_RESTORE();
1606 			} else {
1607 				(void)in_leavegroup(inm, imf);
1608 			}
1609 		}
1610 		ip_mfilter_free(imf);
1611 	}
1612 	free(imo, M_IPMOPTS);
1613 }
1614 
1615 /*
1616  * Atomically get source filters on a socket for an IPv4 multicast group.
1617  * Called with INP lock held; returns with lock released.
1618  */
1619 static int
1620 inp_get_source_filters(struct inpcb *inp, struct sockopt *sopt)
1621 {
1622 	struct epoch_tracker	 et;
1623 	struct __msfilterreq	 msfr;
1624 	sockunion_t		*gsa;
1625 	struct ifnet		*ifp;
1626 	struct ip_moptions	*imo;
1627 	struct in_mfilter	*imf;
1628 	struct ip_msource	*ims;
1629 	struct in_msource	*lims;
1630 	struct sockaddr_in	*psin;
1631 	struct sockaddr_storage	*ptss;
1632 	struct sockaddr_storage	*tss;
1633 	int			 error;
1634 	size_t			 nsrcs, ncsrcs;
1635 
1636 	INP_WLOCK_ASSERT(inp);
1637 
1638 	imo = inp->inp_moptions;
1639 	KASSERT(imo != NULL, ("%s: null ip_moptions", __func__));
1640 
1641 	INP_WUNLOCK(inp);
1642 
1643 	error = sooptcopyin(sopt, &msfr, sizeof(struct __msfilterreq),
1644 	    sizeof(struct __msfilterreq));
1645 	if (error)
1646 		return (error);
1647 
1648 	NET_EPOCH_ENTER(et);
1649 	ifp = ifnet_byindex(msfr.msfr_ifindex);
1650 	NET_EPOCH_EXIT(et);	/* XXXGL: unsafe ifnet pointer left */
1651 	if (ifp == NULL)
1652 		return (EINVAL);
1653 
1654 	INP_WLOCK(inp);
1655 
1656 	/*
1657 	 * Lookup group on the socket.
1658 	 */
1659 	gsa = (sockunion_t *)&msfr.msfr_group;
1660 	imf = imo_match_group(imo, ifp, &gsa->sa);
1661 	if (imf == NULL) {
1662 		INP_WUNLOCK(inp);
1663 		return (EADDRNOTAVAIL);
1664 	}
1665 
1666 	/*
1667 	 * Ignore memberships which are in limbo.
1668 	 */
1669 	if (imf->imf_st[1] == MCAST_UNDEFINED) {
1670 		INP_WUNLOCK(inp);
1671 		return (EAGAIN);
1672 	}
1673 	msfr.msfr_fmode = imf->imf_st[1];
1674 
1675 	/*
1676 	 * If the user specified a buffer, copy out the source filter
1677 	 * entries to userland gracefully.
1678 	 * We only copy out the number of entries which userland
1679 	 * has asked for, but we always tell userland how big the
1680 	 * buffer really needs to be.
1681 	 */
1682 	if (msfr.msfr_nsrcs > in_mcast_maxsocksrc)
1683 		msfr.msfr_nsrcs = in_mcast_maxsocksrc;
1684 	tss = NULL;
1685 	if (msfr.msfr_srcs != NULL && msfr.msfr_nsrcs > 0) {
1686 		tss = malloc(sizeof(struct sockaddr_storage) * msfr.msfr_nsrcs,
1687 		    M_TEMP, M_NOWAIT | M_ZERO);
1688 		if (tss == NULL) {
1689 			INP_WUNLOCK(inp);
1690 			return (ENOBUFS);
1691 		}
1692 	}
1693 
1694 	/*
1695 	 * Count number of sources in-mode at t0.
1696 	 * If buffer space exists and remains, copy out source entries.
1697 	 */
1698 	nsrcs = msfr.msfr_nsrcs;
1699 	ncsrcs = 0;
1700 	ptss = tss;
1701 	RB_FOREACH(ims, ip_msource_tree, &imf->imf_sources) {
1702 		lims = (struct in_msource *)ims;
1703 		if (lims->imsl_st[0] == MCAST_UNDEFINED ||
1704 		    lims->imsl_st[0] != imf->imf_st[0])
1705 			continue;
1706 		++ncsrcs;
1707 		if (tss != NULL && nsrcs > 0) {
1708 			psin = (struct sockaddr_in *)ptss;
1709 			psin->sin_family = AF_INET;
1710 			psin->sin_len = sizeof(struct sockaddr_in);
1711 			psin->sin_addr.s_addr = htonl(lims->ims_haddr);
1712 			psin->sin_port = 0;
1713 			++ptss;
1714 			--nsrcs;
1715 		}
1716 	}
1717 
1718 	INP_WUNLOCK(inp);
1719 
1720 	if (tss != NULL) {
1721 		error = copyout(tss, msfr.msfr_srcs,
1722 		    sizeof(struct sockaddr_storage) * msfr.msfr_nsrcs);
1723 		free(tss, M_TEMP);
1724 		if (error)
1725 			return (error);
1726 	}
1727 
1728 	msfr.msfr_nsrcs = ncsrcs;
1729 	error = sooptcopyout(sopt, &msfr, sizeof(struct __msfilterreq));
1730 
1731 	return (error);
1732 }
1733 
1734 /*
1735  * Return the IP multicast options in response to user getsockopt().
1736  */
1737 int
1738 inp_getmoptions(struct inpcb *inp, struct sockopt *sopt)
1739 {
1740 	struct ip_mreqn		 mreqn;
1741 	struct ip_moptions	*imo;
1742 	struct ifnet		*ifp;
1743 	struct in_ifaddr	*ia;
1744 	int			 error, optval;
1745 	u_char			 coptval;
1746 
1747 	INP_WLOCK(inp);
1748 	imo = inp->inp_moptions;
1749 	/* If socket is neither of type SOCK_RAW or SOCK_DGRAM reject it. */
1750 	if (inp->inp_socket->so_proto->pr_type != SOCK_RAW &&
1751 	    inp->inp_socket->so_proto->pr_type != SOCK_DGRAM) {
1752 		INP_WUNLOCK(inp);
1753 		return (EOPNOTSUPP);
1754 	}
1755 
1756 	error = 0;
1757 	switch (sopt->sopt_name) {
1758 	case IP_MULTICAST_VIF:
1759 		if (imo != NULL)
1760 			optval = imo->imo_multicast_vif;
1761 		else
1762 			optval = -1;
1763 		INP_WUNLOCK(inp);
1764 		error = sooptcopyout(sopt, &optval, sizeof(int));
1765 		break;
1766 
1767 	case IP_MULTICAST_IF:
1768 		memset(&mreqn, 0, sizeof(struct ip_mreqn));
1769 		if (imo != NULL) {
1770 			ifp = imo->imo_multicast_ifp;
1771 			if (!in_nullhost(imo->imo_multicast_addr)) {
1772 				mreqn.imr_address = imo->imo_multicast_addr;
1773 			} else if (ifp != NULL) {
1774 				struct epoch_tracker et;
1775 
1776 				mreqn.imr_ifindex = ifp->if_index;
1777 				NET_EPOCH_ENTER(et);
1778 				IFP_TO_IA(ifp, ia);
1779 				if (ia != NULL)
1780 					mreqn.imr_address =
1781 					    IA_SIN(ia)->sin_addr;
1782 				NET_EPOCH_EXIT(et);
1783 			}
1784 		}
1785 		INP_WUNLOCK(inp);
1786 		if (sopt->sopt_valsize == sizeof(struct ip_mreqn)) {
1787 			error = sooptcopyout(sopt, &mreqn,
1788 			    sizeof(struct ip_mreqn));
1789 		} else {
1790 			error = sooptcopyout(sopt, &mreqn.imr_address,
1791 			    sizeof(struct in_addr));
1792 		}
1793 		break;
1794 
1795 	case IP_MULTICAST_TTL:
1796 		if (imo == NULL)
1797 			optval = coptval = IP_DEFAULT_MULTICAST_TTL;
1798 		else
1799 			optval = coptval = imo->imo_multicast_ttl;
1800 		INP_WUNLOCK(inp);
1801 		if (sopt->sopt_valsize == sizeof(u_char))
1802 			error = sooptcopyout(sopt, &coptval, sizeof(u_char));
1803 		else
1804 			error = sooptcopyout(sopt, &optval, sizeof(int));
1805 		break;
1806 
1807 	case IP_MULTICAST_LOOP:
1808 		if (imo == NULL)
1809 			optval = coptval = IP_DEFAULT_MULTICAST_LOOP;
1810 		else
1811 			optval = coptval = imo->imo_multicast_loop;
1812 		INP_WUNLOCK(inp);
1813 		if (sopt->sopt_valsize == sizeof(u_char))
1814 			error = sooptcopyout(sopt, &coptval, sizeof(u_char));
1815 		else
1816 			error = sooptcopyout(sopt, &optval, sizeof(int));
1817 		break;
1818 
1819 	case IP_MSFILTER:
1820 		if (imo == NULL) {
1821 			error = EADDRNOTAVAIL;
1822 			INP_WUNLOCK(inp);
1823 		} else {
1824 			error = inp_get_source_filters(inp, sopt);
1825 		}
1826 		break;
1827 
1828 	default:
1829 		INP_WUNLOCK(inp);
1830 		error = ENOPROTOOPT;
1831 		break;
1832 	}
1833 
1834 	INP_UNLOCK_ASSERT(inp);
1835 
1836 	return (error);
1837 }
1838 
1839 /*
1840  * Look up the ifnet to use for a multicast group membership,
1841  * given the IPv4 address of an interface, and the IPv4 group address.
1842  *
1843  * This routine exists to support legacy multicast applications
1844  * which do not understand that multicast memberships are scoped to
1845  * specific physical links in the networking stack, or which need
1846  * to join link-scope groups before IPv4 addresses are configured.
1847  *
1848  * Use this socket's current FIB number for any required FIB lookup.
1849  * If ina is INADDR_ANY, look up the group address in the unicast FIB,
1850  * and use its ifp; usually, this points to the default next-hop.
1851  *
1852  * If the FIB lookup fails, attempt to use the first non-loopback
1853  * interface with multicast capability in the system as a
1854  * last resort. The legacy IPv4 ASM API requires that we do
1855  * this in order to allow groups to be joined when the routing
1856  * table has not yet been populated during boot.
1857  *
1858  * Returns NULL if no ifp could be found, otherwise return referenced ifp.
1859  *
1860  * FUTURE: Implement IPv4 source-address selection.
1861  */
1862 static struct ifnet *
1863 inp_lookup_mcast_ifp(const struct inpcb *inp,
1864     const struct sockaddr_in *gsin, const struct in_addr ina)
1865 {
1866 	struct ifnet *ifp;
1867 	struct nhop_object *nh;
1868 
1869 	NET_EPOCH_ASSERT();
1870 	KASSERT(inp != NULL, ("%s: inp must not be NULL", __func__));
1871 	KASSERT(gsin->sin_family == AF_INET, ("%s: not AF_INET", __func__));
1872 	KASSERT(IN_MULTICAST(ntohl(gsin->sin_addr.s_addr)),
1873 	    ("%s: not multicast", __func__));
1874 
1875 	ifp = NULL;
1876 	if (!in_nullhost(ina)) {
1877 		INADDR_TO_IFP(ina, ifp);
1878 		if (ifp != NULL)
1879 			if_ref(ifp);
1880 	} else {
1881 		nh = fib4_lookup(inp->inp_inc.inc_fibnum, gsin->sin_addr, 0, NHR_NONE, 0);
1882 		if (nh != NULL) {
1883 			ifp = nh->nh_ifp;
1884 			if_ref(ifp);
1885 		} else {
1886 			struct in_ifaddr *ia;
1887 			struct ifnet *mifp;
1888 
1889 			mifp = NULL;
1890 			CK_STAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
1891 				mifp = ia->ia_ifp;
1892 				if (!(mifp->if_flags & IFF_LOOPBACK) &&
1893 				     (mifp->if_flags & IFF_MULTICAST)) {
1894 					ifp = mifp;
1895 					if_ref(ifp);
1896 					break;
1897 				}
1898 			}
1899 		}
1900 	}
1901 
1902 	return (ifp);
1903 }
1904 
1905 /*
1906  * Join an IPv4 multicast group, possibly with a source.
1907  */
1908 static int
1909 inp_join_group(struct inpcb *inp, struct sockopt *sopt)
1910 {
1911 	struct group_source_req		 gsr;
1912 	sockunion_t			*gsa, *ssa;
1913 	struct ifnet			*ifp;
1914 	struct in_mfilter		*imf;
1915 	struct ip_moptions		*imo;
1916 	struct in_multi			*inm;
1917 	struct in_msource		*lims;
1918 	struct epoch_tracker		 et;
1919 	int				 error, is_new;
1920 
1921 	ifp = NULL;
1922 	lims = NULL;
1923 	error = 0;
1924 
1925 	memset(&gsr, 0, sizeof(struct group_source_req));
1926 	gsa = (sockunion_t *)&gsr.gsr_group;
1927 	gsa->ss.ss_family = AF_UNSPEC;
1928 	ssa = (sockunion_t *)&gsr.gsr_source;
1929 	ssa->ss.ss_family = AF_UNSPEC;
1930 
1931 	switch (sopt->sopt_name) {
1932 	case IP_ADD_MEMBERSHIP: {
1933 		struct ip_mreqn mreqn;
1934 
1935 		if (sopt->sopt_valsize == sizeof(struct ip_mreqn))
1936 			error = sooptcopyin(sopt, &mreqn,
1937 			    sizeof(struct ip_mreqn), sizeof(struct ip_mreqn));
1938 		else
1939 			error = sooptcopyin(sopt, &mreqn,
1940 			    sizeof(struct ip_mreq), sizeof(struct ip_mreq));
1941 		if (error)
1942 			return (error);
1943 
1944 		gsa->sin.sin_family = AF_INET;
1945 		gsa->sin.sin_len = sizeof(struct sockaddr_in);
1946 		gsa->sin.sin_addr = mreqn.imr_multiaddr;
1947 		if (!IN_MULTICAST(ntohl(gsa->sin.sin_addr.s_addr)))
1948 			return (EINVAL);
1949 
1950 		NET_EPOCH_ENTER(et);
1951 		if (sopt->sopt_valsize == sizeof(struct ip_mreqn) &&
1952 		    mreqn.imr_ifindex != 0)
1953 			ifp = ifnet_byindex_ref(mreqn.imr_ifindex);
1954 		else
1955 			ifp = inp_lookup_mcast_ifp(inp, &gsa->sin,
1956 			    mreqn.imr_address);
1957 		NET_EPOCH_EXIT(et);
1958 		break;
1959 	}
1960 	case IP_ADD_SOURCE_MEMBERSHIP: {
1961 		struct ip_mreq_source	 mreqs;
1962 
1963 		error = sooptcopyin(sopt, &mreqs, sizeof(struct ip_mreq_source),
1964 			    sizeof(struct ip_mreq_source));
1965 		if (error)
1966 			return (error);
1967 
1968 		gsa->sin.sin_family = ssa->sin.sin_family = AF_INET;
1969 		gsa->sin.sin_len = ssa->sin.sin_len =
1970 		    sizeof(struct sockaddr_in);
1971 
1972 		gsa->sin.sin_addr = mreqs.imr_multiaddr;
1973 		if (!IN_MULTICAST(ntohl(gsa->sin.sin_addr.s_addr)))
1974 			return (EINVAL);
1975 
1976 		ssa->sin.sin_addr = mreqs.imr_sourceaddr;
1977 
1978 		NET_EPOCH_ENTER(et);
1979 		ifp = inp_lookup_mcast_ifp(inp, &gsa->sin,
1980 		    mreqs.imr_interface);
1981 		NET_EPOCH_EXIT(et);
1982 		CTR3(KTR_IGMPV3, "%s: imr_interface = 0x%08x, ifp = %p",
1983 		    __func__, ntohl(mreqs.imr_interface.s_addr), ifp);
1984 		break;
1985 	}
1986 
1987 	case MCAST_JOIN_GROUP:
1988 	case MCAST_JOIN_SOURCE_GROUP:
1989 		if (sopt->sopt_name == MCAST_JOIN_GROUP) {
1990 			error = sooptcopyin(sopt, &gsr,
1991 			    sizeof(struct group_req),
1992 			    sizeof(struct group_req));
1993 		} else if (sopt->sopt_name == MCAST_JOIN_SOURCE_GROUP) {
1994 			error = sooptcopyin(sopt, &gsr,
1995 			    sizeof(struct group_source_req),
1996 			    sizeof(struct group_source_req));
1997 		}
1998 		if (error)
1999 			return (error);
2000 
2001 		if (gsa->sin.sin_family != AF_INET ||
2002 		    gsa->sin.sin_len != sizeof(struct sockaddr_in))
2003 			return (EINVAL);
2004 
2005 		/*
2006 		 * Overwrite the port field if present, as the sockaddr
2007 		 * being copied in may be matched with a binary comparison.
2008 		 */
2009 		gsa->sin.sin_port = 0;
2010 		if (sopt->sopt_name == MCAST_JOIN_SOURCE_GROUP) {
2011 			if (ssa->sin.sin_family != AF_INET ||
2012 			    ssa->sin.sin_len != sizeof(struct sockaddr_in))
2013 				return (EINVAL);
2014 			ssa->sin.sin_port = 0;
2015 		}
2016 
2017 		if (!IN_MULTICAST(ntohl(gsa->sin.sin_addr.s_addr)))
2018 			return (EINVAL);
2019 
2020 		NET_EPOCH_ENTER(et);
2021 		ifp = ifnet_byindex_ref(gsr.gsr_interface);
2022 		NET_EPOCH_EXIT(et);
2023 		if (ifp == NULL)
2024 			return (EADDRNOTAVAIL);
2025 		break;
2026 
2027 	default:
2028 		CTR2(KTR_IGMPV3, "%s: unknown sopt_name %d",
2029 		    __func__, sopt->sopt_name);
2030 		return (EOPNOTSUPP);
2031 		break;
2032 	}
2033 
2034 	if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) {
2035 		if (ifp != NULL)
2036 			if_rele(ifp);
2037 		return (EADDRNOTAVAIL);
2038 	}
2039 
2040 	IN_MULTI_LOCK();
2041 
2042 	/*
2043 	 * Find the membership in the membership list.
2044 	 */
2045 	imo = inp_findmoptions(inp);
2046 	imf = imo_match_group(imo, ifp, &gsa->sa);
2047 	if (imf == NULL) {
2048 		is_new = 1;
2049 		inm = NULL;
2050 
2051 		if (ip_mfilter_count(&imo->imo_head) >= IP_MAX_MEMBERSHIPS) {
2052 			error = ENOMEM;
2053 			goto out_inp_locked;
2054 		}
2055 	} else {
2056 		is_new = 0;
2057 		inm = imf->imf_inm;
2058 
2059 		if (ssa->ss.ss_family != AF_UNSPEC) {
2060 			/*
2061 			 * MCAST_JOIN_SOURCE_GROUP on an exclusive membership
2062 			 * is an error. On an existing inclusive membership,
2063 			 * it just adds the source to the filter list.
2064 			 */
2065 			if (imf->imf_st[1] != MCAST_INCLUDE) {
2066 				error = EINVAL;
2067 				goto out_inp_locked;
2068 			}
2069 			/*
2070 			 * Throw out duplicates.
2071 			 *
2072 			 * XXX FIXME: This makes a naive assumption that
2073 			 * even if entries exist for *ssa in this imf,
2074 			 * they will be rejected as dupes, even if they
2075 			 * are not valid in the current mode (in-mode).
2076 			 *
2077 			 * in_msource is transactioned just as for anything
2078 			 * else in SSM -- but note naive use of inm_graft()
2079 			 * below for allocating new filter entries.
2080 			 *
2081 			 * This is only an issue if someone mixes the
2082 			 * full-state SSM API with the delta-based API,
2083 			 * which is discouraged in the relevant RFCs.
2084 			 */
2085 			lims = imo_match_source(imf, &ssa->sa);
2086 			if (lims != NULL /*&&
2087 			    lims->imsl_st[1] == MCAST_INCLUDE*/) {
2088 				error = EADDRNOTAVAIL;
2089 				goto out_inp_locked;
2090 			}
2091 		} else {
2092 			/*
2093 			 * MCAST_JOIN_GROUP on an existing exclusive
2094 			 * membership is an error; return EADDRINUSE
2095 			 * to preserve 4.4BSD API idempotence, and
2096 			 * avoid tedious detour to code below.
2097 			 * NOTE: This is bending RFC 3678 a bit.
2098 			 *
2099 			 * On an existing inclusive membership, this is also
2100 			 * an error; if you want to change filter mode,
2101 			 * you must use the userland API setsourcefilter().
2102 			 * XXX We don't reject this for imf in UNDEFINED
2103 			 * state at t1, because allocation of a filter
2104 			 * is atomic with allocation of a membership.
2105 			 */
2106 			error = EINVAL;
2107 			if (imf->imf_st[1] == MCAST_EXCLUDE)
2108 				error = EADDRINUSE;
2109 			goto out_inp_locked;
2110 		}
2111 	}
2112 
2113 	/*
2114 	 * Begin state merge transaction at socket layer.
2115 	 */
2116 	INP_WLOCK_ASSERT(inp);
2117 
2118 	/*
2119 	 * Graft new source into filter list for this inpcb's
2120 	 * membership of the group. The in_multi may not have
2121 	 * been allocated yet if this is a new membership, however,
2122 	 * the in_mfilter slot will be allocated and must be initialized.
2123 	 *
2124 	 * Note: Grafting of exclusive mode filters doesn't happen
2125 	 * in this path.
2126 	 * XXX: Should check for non-NULL lims (node exists but may
2127 	 * not be in-mode) for interop with full-state API.
2128 	 */
2129 	if (ssa->ss.ss_family != AF_UNSPEC) {
2130 		/* Membership starts in IN mode */
2131 		if (is_new) {
2132 			CTR1(KTR_IGMPV3, "%s: new join w/source", __func__);
2133 			imf = ip_mfilter_alloc(M_NOWAIT, MCAST_UNDEFINED, MCAST_INCLUDE);
2134 			if (imf == NULL) {
2135 				error = ENOMEM;
2136 				goto out_inp_locked;
2137 			}
2138 		} else {
2139 			CTR2(KTR_IGMPV3, "%s: %s source", __func__, "allow");
2140 		}
2141 		lims = imf_graft(imf, MCAST_INCLUDE, &ssa->sin);
2142 		if (lims == NULL) {
2143 			CTR1(KTR_IGMPV3, "%s: merge imf state failed",
2144 			    __func__);
2145 			error = ENOMEM;
2146 			goto out_inp_locked;
2147 		}
2148 	} else {
2149 		/* No address specified; Membership starts in EX mode */
2150 		if (is_new) {
2151 			CTR1(KTR_IGMPV3, "%s: new join w/o source", __func__);
2152 			imf = ip_mfilter_alloc(M_NOWAIT, MCAST_UNDEFINED, MCAST_EXCLUDE);
2153 			if (imf == NULL) {
2154 				error = ENOMEM;
2155 				goto out_inp_locked;
2156 			}
2157 		}
2158 	}
2159 
2160 	/*
2161 	 * Begin state merge transaction at IGMP layer.
2162 	 */
2163 	if (is_new) {
2164 		in_pcbref(inp);
2165 		INP_WUNLOCK(inp);
2166 
2167 		error = in_joingroup_locked(ifp, &gsa->sin.sin_addr, imf,
2168 		    &imf->imf_inm);
2169 
2170 		INP_WLOCK(inp);
2171 		if (in_pcbrele_wlocked(inp)) {
2172 			error = ENXIO;
2173 			goto out_inp_unlocked;
2174 		}
2175 		if (error) {
2176                         CTR1(KTR_IGMPV3, "%s: in_joingroup_locked failed",
2177                             __func__);
2178 			goto out_inp_locked;
2179 		}
2180 		/*
2181 		 * NOTE: Refcount from in_joingroup_locked()
2182 		 * is protecting membership.
2183 		 */
2184 		ip_mfilter_insert(&imo->imo_head, imf);
2185 	} else {
2186 		CTR1(KTR_IGMPV3, "%s: merge inm state", __func__);
2187 		IN_MULTI_LIST_LOCK();
2188 		error = inm_merge(inm, imf);
2189 		if (error) {
2190 			CTR1(KTR_IGMPV3, "%s: failed to merge inm state",
2191 				 __func__);
2192 			IN_MULTI_LIST_UNLOCK();
2193 			imf_rollback(imf);
2194 			imf_reap(imf);
2195 			goto out_inp_locked;
2196 		}
2197 		CTR1(KTR_IGMPV3, "%s: doing igmp downcall", __func__);
2198 		error = igmp_change_state(inm);
2199 		IN_MULTI_LIST_UNLOCK();
2200 		if (error) {
2201 			CTR1(KTR_IGMPV3, "%s: failed igmp downcall",
2202 			    __func__);
2203 			imf_rollback(imf);
2204 			imf_reap(imf);
2205 			goto out_inp_locked;
2206 		}
2207 	}
2208 
2209 	imf_commit(imf);
2210 	imf = NULL;
2211 
2212 out_inp_locked:
2213 	INP_WUNLOCK(inp);
2214 out_inp_unlocked:
2215 	IN_MULTI_UNLOCK();
2216 
2217 	if (is_new && imf) {
2218 		if (imf->imf_inm != NULL) {
2219 			IN_MULTI_LIST_LOCK();
2220 			IF_ADDR_WLOCK(ifp);
2221 			inm_release_deferred(imf->imf_inm);
2222 			IF_ADDR_WUNLOCK(ifp);
2223 			IN_MULTI_LIST_UNLOCK();
2224 		}
2225 		ip_mfilter_free(imf);
2226 	}
2227 	if_rele(ifp);
2228 	return (error);
2229 }
2230 
2231 /*
2232  * Leave an IPv4 multicast group on an inpcb, possibly with a source.
2233  */
2234 static int
2235 inp_leave_group(struct inpcb *inp, struct sockopt *sopt)
2236 {
2237 	struct epoch_tracker		 et;
2238 	struct group_source_req		 gsr;
2239 	struct ip_mreq_source		 mreqs;
2240 	sockunion_t			*gsa, *ssa;
2241 	struct ifnet			*ifp;
2242 	struct in_mfilter		*imf;
2243 	struct ip_moptions		*imo;
2244 	struct in_msource		*ims;
2245 	struct in_multi			*inm;
2246 	int				 error;
2247 	bool				 is_final;
2248 
2249 	ifp = NULL;
2250 	error = 0;
2251 	is_final = true;
2252 
2253 	memset(&gsr, 0, sizeof(struct group_source_req));
2254 	gsa = (sockunion_t *)&gsr.gsr_group;
2255 	gsa->ss.ss_family = AF_UNSPEC;
2256 	ssa = (sockunion_t *)&gsr.gsr_source;
2257 	ssa->ss.ss_family = AF_UNSPEC;
2258 
2259 	switch (sopt->sopt_name) {
2260 	case IP_DROP_MEMBERSHIP:
2261 	case IP_DROP_SOURCE_MEMBERSHIP:
2262 		if (sopt->sopt_name == IP_DROP_MEMBERSHIP) {
2263 			error = sooptcopyin(sopt, &mreqs,
2264 			    sizeof(struct ip_mreq),
2265 			    sizeof(struct ip_mreq));
2266 			/*
2267 			 * Swap interface and sourceaddr arguments,
2268 			 * as ip_mreq and ip_mreq_source are laid
2269 			 * out differently.
2270 			 */
2271 			mreqs.imr_interface = mreqs.imr_sourceaddr;
2272 			mreqs.imr_sourceaddr.s_addr = INADDR_ANY;
2273 		} else if (sopt->sopt_name == IP_DROP_SOURCE_MEMBERSHIP) {
2274 			error = sooptcopyin(sopt, &mreqs,
2275 			    sizeof(struct ip_mreq_source),
2276 			    sizeof(struct ip_mreq_source));
2277 		}
2278 		if (error)
2279 			return (error);
2280 
2281 		gsa->sin.sin_family = AF_INET;
2282 		gsa->sin.sin_len = sizeof(struct sockaddr_in);
2283 		gsa->sin.sin_addr = mreqs.imr_multiaddr;
2284 
2285 		if (sopt->sopt_name == IP_DROP_SOURCE_MEMBERSHIP) {
2286 			ssa->sin.sin_family = AF_INET;
2287 			ssa->sin.sin_len = sizeof(struct sockaddr_in);
2288 			ssa->sin.sin_addr = mreqs.imr_sourceaddr;
2289 		}
2290 
2291 		/*
2292 		 * Attempt to look up hinted ifp from interface address.
2293 		 * Fallthrough with null ifp iff lookup fails, to
2294 		 * preserve 4.4BSD mcast API idempotence.
2295 		 * XXX NOTE WELL: The RFC 3678 API is preferred because
2296 		 * using an IPv4 address as a key is racy.
2297 		 */
2298 		if (!in_nullhost(mreqs.imr_interface)) {
2299 			NET_EPOCH_ENTER(et);
2300 			INADDR_TO_IFP(mreqs.imr_interface, ifp);
2301 			/* XXXGL ifref? */
2302 			NET_EPOCH_EXIT(et);
2303 		}
2304 		CTR3(KTR_IGMPV3, "%s: imr_interface = 0x%08x, ifp = %p",
2305 		    __func__, ntohl(mreqs.imr_interface.s_addr), ifp);
2306 
2307 		break;
2308 
2309 	case MCAST_LEAVE_GROUP:
2310 	case MCAST_LEAVE_SOURCE_GROUP:
2311 		if (sopt->sopt_name == MCAST_LEAVE_GROUP) {
2312 			error = sooptcopyin(sopt, &gsr,
2313 			    sizeof(struct group_req),
2314 			    sizeof(struct group_req));
2315 		} else if (sopt->sopt_name == MCAST_LEAVE_SOURCE_GROUP) {
2316 			error = sooptcopyin(sopt, &gsr,
2317 			    sizeof(struct group_source_req),
2318 			    sizeof(struct group_source_req));
2319 		}
2320 		if (error)
2321 			return (error);
2322 
2323 		if (gsa->sin.sin_family != AF_INET ||
2324 		    gsa->sin.sin_len != sizeof(struct sockaddr_in))
2325 			return (EINVAL);
2326 
2327 		if (sopt->sopt_name == MCAST_LEAVE_SOURCE_GROUP) {
2328 			if (ssa->sin.sin_family != AF_INET ||
2329 			    ssa->sin.sin_len != sizeof(struct sockaddr_in))
2330 				return (EINVAL);
2331 		}
2332 
2333 		NET_EPOCH_ENTER(et);
2334 		ifp = ifnet_byindex(gsr.gsr_interface);
2335 		NET_EPOCH_EXIT(et);	/* XXXGL: unsafe ifp */
2336 		if (ifp == NULL)
2337 			return (EADDRNOTAVAIL);
2338 		break;
2339 
2340 	default:
2341 		CTR2(KTR_IGMPV3, "%s: unknown sopt_name %d",
2342 		    __func__, sopt->sopt_name);
2343 		return (EOPNOTSUPP);
2344 		break;
2345 	}
2346 
2347 	if (!IN_MULTICAST(ntohl(gsa->sin.sin_addr.s_addr)))
2348 		return (EINVAL);
2349 
2350 	IN_MULTI_LOCK();
2351 
2352 	/*
2353 	 * Find the membership in the membership list.
2354 	 */
2355 	imo = inp_findmoptions(inp);
2356 	imf = imo_match_group(imo, ifp, &gsa->sa);
2357 	if (imf == NULL) {
2358 		error = EADDRNOTAVAIL;
2359 		goto out_inp_locked;
2360 	}
2361 	inm = imf->imf_inm;
2362 
2363 	if (ssa->ss.ss_family != AF_UNSPEC)
2364 		is_final = false;
2365 
2366 	/*
2367 	 * Begin state merge transaction at socket layer.
2368 	 */
2369 	INP_WLOCK_ASSERT(inp);
2370 
2371 	/*
2372 	 * If we were instructed only to leave a given source, do so.
2373 	 * MCAST_LEAVE_SOURCE_GROUP is only valid for inclusive memberships.
2374 	 */
2375 	if (is_final) {
2376 		ip_mfilter_remove(&imo->imo_head, imf);
2377 		imf_leave(imf);
2378 
2379 		/*
2380 		 * Give up the multicast address record to which
2381 		 * the membership points.
2382 		 */
2383 		(void) in_leavegroup_locked(imf->imf_inm, imf);
2384 	} else {
2385 		if (imf->imf_st[0] == MCAST_EXCLUDE) {
2386 			error = EADDRNOTAVAIL;
2387 			goto out_inp_locked;
2388 		}
2389 		ims = imo_match_source(imf, &ssa->sa);
2390 		if (ims == NULL) {
2391 			CTR3(KTR_IGMPV3, "%s: source 0x%08x %spresent",
2392 			    __func__, ntohl(ssa->sin.sin_addr.s_addr), "not ");
2393 			error = EADDRNOTAVAIL;
2394 			goto out_inp_locked;
2395 		}
2396 		CTR2(KTR_IGMPV3, "%s: %s source", __func__, "block");
2397 		error = imf_prune(imf, &ssa->sin);
2398 		if (error) {
2399 			CTR1(KTR_IGMPV3, "%s: merge imf state failed",
2400 			    __func__);
2401 			goto out_inp_locked;
2402 		}
2403 	}
2404 
2405 	/*
2406 	 * Begin state merge transaction at IGMP layer.
2407 	 */
2408 	if (!is_final) {
2409 		CTR1(KTR_IGMPV3, "%s: merge inm state", __func__);
2410 		IN_MULTI_LIST_LOCK();
2411 		error = inm_merge(inm, imf);
2412 		if (error) {
2413 			CTR1(KTR_IGMPV3, "%s: failed to merge inm state",
2414 			    __func__);
2415 			IN_MULTI_LIST_UNLOCK();
2416 			imf_rollback(imf);
2417 			imf_reap(imf);
2418 			goto out_inp_locked;
2419 		}
2420 
2421 		CTR1(KTR_IGMPV3, "%s: doing igmp downcall", __func__);
2422 		error = igmp_change_state(inm);
2423 		IN_MULTI_LIST_UNLOCK();
2424 		if (error) {
2425 			CTR1(KTR_IGMPV3, "%s: failed igmp downcall",
2426 			    __func__);
2427 			imf_rollback(imf);
2428 			imf_reap(imf);
2429 			goto out_inp_locked;
2430 		}
2431 	}
2432 	imf_commit(imf);
2433 	imf_reap(imf);
2434 
2435 out_inp_locked:
2436 	INP_WUNLOCK(inp);
2437 
2438 	if (is_final && imf)
2439 		ip_mfilter_free(imf);
2440 
2441 	IN_MULTI_UNLOCK();
2442 	return (error);
2443 }
2444 
2445 /*
2446  * Select the interface for transmitting IPv4 multicast datagrams.
2447  *
2448  * Either an instance of struct in_addr or an instance of struct ip_mreqn
2449  * may be passed to this socket option. An address of INADDR_ANY or an
2450  * interface index of 0 is used to remove a previous selection.
2451  * When no interface is selected, one is chosen for every send.
2452  */
2453 static int
2454 inp_set_multicast_if(struct inpcb *inp, struct sockopt *sopt)
2455 {
2456 	struct in_addr		 addr;
2457 	struct ip_mreqn		 mreqn;
2458 	struct ifnet		*ifp;
2459 	struct ip_moptions	*imo;
2460 	int			 error;
2461 
2462 	if (sopt->sopt_valsize == sizeof(struct ip_mreqn)) {
2463 		/*
2464 		 * An interface index was specified using the
2465 		 * Linux-derived ip_mreqn structure.
2466 		 */
2467 		error = sooptcopyin(sopt, &mreqn, sizeof(struct ip_mreqn),
2468 		    sizeof(struct ip_mreqn));
2469 		if (error)
2470 			return (error);
2471 
2472 		if (mreqn.imr_ifindex < 0)
2473 			return (EINVAL);
2474 
2475 		if (mreqn.imr_ifindex == 0) {
2476 			ifp = NULL;
2477 		} else {
2478 			struct epoch_tracker et;
2479 
2480 			NET_EPOCH_ENTER(et);
2481 			ifp = ifnet_byindex(mreqn.imr_ifindex);
2482 			NET_EPOCH_EXIT(et);	/* XXXGL: unsafe ifp */
2483 			if (ifp == NULL)
2484 				return (EADDRNOTAVAIL);
2485 		}
2486 	} else {
2487 		/*
2488 		 * An interface was specified by IPv4 address.
2489 		 * This is the traditional BSD usage.
2490 		 */
2491 		error = sooptcopyin(sopt, &addr, sizeof(struct in_addr),
2492 		    sizeof(struct in_addr));
2493 		if (error)
2494 			return (error);
2495 		if (in_nullhost(addr)) {
2496 			ifp = NULL;
2497 		} else {
2498 			struct epoch_tracker et;
2499 
2500 			NET_EPOCH_ENTER(et);
2501 			INADDR_TO_IFP(addr, ifp);
2502 			/* XXXGL ifref? */
2503 			NET_EPOCH_EXIT(et);
2504 			if (ifp == NULL)
2505 				return (EADDRNOTAVAIL);
2506 		}
2507 		CTR3(KTR_IGMPV3, "%s: ifp = %p, addr = 0x%08x", __func__, ifp,
2508 		    ntohl(addr.s_addr));
2509 	}
2510 
2511 	/* Reject interfaces which do not support multicast. */
2512 	if (ifp != NULL && (ifp->if_flags & IFF_MULTICAST) == 0)
2513 		return (EOPNOTSUPP);
2514 
2515 	imo = inp_findmoptions(inp);
2516 	imo->imo_multicast_ifp = ifp;
2517 	imo->imo_multicast_addr.s_addr = INADDR_ANY;
2518 	INP_WUNLOCK(inp);
2519 
2520 	return (0);
2521 }
2522 
2523 /*
2524  * Atomically set source filters on a socket for an IPv4 multicast group.
2525  *
2526  * SMPng: NOTE: Potentially calls malloc(M_WAITOK) with Giant held.
2527  */
2528 static int
2529 inp_set_source_filters(struct inpcb *inp, struct sockopt *sopt)
2530 {
2531 	struct epoch_tracker	 et;
2532 	struct __msfilterreq	 msfr;
2533 	sockunion_t		*gsa;
2534 	struct ifnet		*ifp;
2535 	struct in_mfilter	*imf;
2536 	struct ip_moptions	*imo;
2537 	struct in_multi		*inm;
2538 	int			 error;
2539 
2540 	error = sooptcopyin(sopt, &msfr, sizeof(struct __msfilterreq),
2541 	    sizeof(struct __msfilterreq));
2542 	if (error)
2543 		return (error);
2544 
2545 	if (msfr.msfr_nsrcs > in_mcast_maxsocksrc)
2546 		return (ENOBUFS);
2547 
2548 	if ((msfr.msfr_fmode != MCAST_EXCLUDE &&
2549 	     msfr.msfr_fmode != MCAST_INCLUDE))
2550 		return (EINVAL);
2551 
2552 	if (msfr.msfr_group.ss_family != AF_INET ||
2553 	    msfr.msfr_group.ss_len != sizeof(struct sockaddr_in))
2554 		return (EINVAL);
2555 
2556 	gsa = (sockunion_t *)&msfr.msfr_group;
2557 	if (!IN_MULTICAST(ntohl(gsa->sin.sin_addr.s_addr)))
2558 		return (EINVAL);
2559 
2560 	gsa->sin.sin_port = 0;	/* ignore port */
2561 
2562 	NET_EPOCH_ENTER(et);
2563 	ifp = ifnet_byindex(msfr.msfr_ifindex);
2564 	NET_EPOCH_EXIT(et);	/* XXXGL: unsafe ifp */
2565 	if (ifp == NULL)
2566 		return (EADDRNOTAVAIL);
2567 
2568 	IN_MULTI_LOCK();
2569 
2570 	/*
2571 	 * Take the INP write lock.
2572 	 * Check if this socket is a member of this group.
2573 	 */
2574 	imo = inp_findmoptions(inp);
2575 	imf = imo_match_group(imo, ifp, &gsa->sa);
2576 	if (imf == NULL) {
2577 		error = EADDRNOTAVAIL;
2578 		goto out_inp_locked;
2579 	}
2580 	inm = imf->imf_inm;
2581 
2582 	/*
2583 	 * Begin state merge transaction at socket layer.
2584 	 */
2585 	INP_WLOCK_ASSERT(inp);
2586 
2587 	imf->imf_st[1] = msfr.msfr_fmode;
2588 
2589 	/*
2590 	 * Apply any new source filters, if present.
2591 	 * Make a copy of the user-space source vector so
2592 	 * that we may copy them with a single copyin. This
2593 	 * allows us to deal with page faults up-front.
2594 	 */
2595 	if (msfr.msfr_nsrcs > 0) {
2596 		struct in_msource	*lims;
2597 		struct sockaddr_in	*psin;
2598 		struct sockaddr_storage	*kss, *pkss;
2599 		int			 i;
2600 
2601 		INP_WUNLOCK(inp);
2602 
2603 		CTR2(KTR_IGMPV3, "%s: loading %lu source list entries",
2604 		    __func__, (unsigned long)msfr.msfr_nsrcs);
2605 		kss = malloc(sizeof(struct sockaddr_storage) * msfr.msfr_nsrcs,
2606 		    M_TEMP, M_WAITOK);
2607 		error = copyin(msfr.msfr_srcs, kss,
2608 		    sizeof(struct sockaddr_storage) * msfr.msfr_nsrcs);
2609 		if (error) {
2610 			free(kss, M_TEMP);
2611 			return (error);
2612 		}
2613 
2614 		INP_WLOCK(inp);
2615 
2616 		/*
2617 		 * Mark all source filters as UNDEFINED at t1.
2618 		 * Restore new group filter mode, as imf_leave()
2619 		 * will set it to INCLUDE.
2620 		 */
2621 		imf_leave(imf);
2622 		imf->imf_st[1] = msfr.msfr_fmode;
2623 
2624 		/*
2625 		 * Update socket layer filters at t1, lazy-allocating
2626 		 * new entries. This saves a bunch of memory at the
2627 		 * cost of one RB_FIND() per source entry; duplicate
2628 		 * entries in the msfr_nsrcs vector are ignored.
2629 		 * If we encounter an error, rollback transaction.
2630 		 *
2631 		 * XXX This too could be replaced with a set-symmetric
2632 		 * difference like loop to avoid walking from root
2633 		 * every time, as the key space is common.
2634 		 */
2635 		for (i = 0, pkss = kss; i < msfr.msfr_nsrcs; i++, pkss++) {
2636 			psin = (struct sockaddr_in *)pkss;
2637 			if (psin->sin_family != AF_INET) {
2638 				error = EAFNOSUPPORT;
2639 				break;
2640 			}
2641 			if (psin->sin_len != sizeof(struct sockaddr_in)) {
2642 				error = EINVAL;
2643 				break;
2644 			}
2645 			error = imf_get_source(imf, psin, &lims);
2646 			if (error)
2647 				break;
2648 			lims->imsl_st[1] = imf->imf_st[1];
2649 		}
2650 		free(kss, M_TEMP);
2651 	}
2652 
2653 	if (error)
2654 		goto out_imf_rollback;
2655 
2656 	INP_WLOCK_ASSERT(inp);
2657 
2658 	/*
2659 	 * Begin state merge transaction at IGMP layer.
2660 	 */
2661 	CTR1(KTR_IGMPV3, "%s: merge inm state", __func__);
2662 	IN_MULTI_LIST_LOCK();
2663 	error = inm_merge(inm, imf);
2664 	if (error) {
2665 		CTR1(KTR_IGMPV3, "%s: failed to merge inm state", __func__);
2666 		IN_MULTI_LIST_UNLOCK();
2667 		goto out_imf_rollback;
2668 	}
2669 
2670 	CTR1(KTR_IGMPV3, "%s: doing igmp downcall", __func__);
2671 	error = igmp_change_state(inm);
2672 	IN_MULTI_LIST_UNLOCK();
2673 	if (error)
2674 		CTR1(KTR_IGMPV3, "%s: failed igmp downcall", __func__);
2675 
2676 out_imf_rollback:
2677 	if (error)
2678 		imf_rollback(imf);
2679 	else
2680 		imf_commit(imf);
2681 
2682 	imf_reap(imf);
2683 
2684 out_inp_locked:
2685 	INP_WUNLOCK(inp);
2686 	IN_MULTI_UNLOCK();
2687 	return (error);
2688 }
2689 
2690 /*
2691  * Set the IP multicast options in response to user setsockopt().
2692  *
2693  * Many of the socket options handled in this function duplicate the
2694  * functionality of socket options in the regular unicast API. However,
2695  * it is not possible to merge the duplicate code, because the idempotence
2696  * of the IPv4 multicast part of the BSD Sockets API must be preserved;
2697  * the effects of these options must be treated as separate and distinct.
2698  *
2699  * SMPng: XXX: Unlocked read of inp_socket believed OK.
2700  * FUTURE: The IP_MULTICAST_VIF option may be eliminated if MROUTING
2701  * is refactored to no longer use vifs.
2702  */
2703 int
2704 inp_setmoptions(struct inpcb *inp, struct sockopt *sopt)
2705 {
2706 	struct ip_moptions	*imo;
2707 	int			 error;
2708 
2709 	error = 0;
2710 
2711 	/* If socket is neither of type SOCK_RAW or SOCK_DGRAM, reject it. */
2712 	if (inp->inp_socket->so_proto->pr_type != SOCK_RAW &&
2713 	     inp->inp_socket->so_proto->pr_type != SOCK_DGRAM)
2714 		return (EOPNOTSUPP);
2715 
2716 	switch (sopt->sopt_name) {
2717 	case IP_MULTICAST_VIF: {
2718 		int vifi;
2719 		/*
2720 		 * Select a multicast VIF for transmission.
2721 		 * Only useful if multicast forwarding is active.
2722 		 */
2723 		if (legal_vif_num == NULL) {
2724 			error = EOPNOTSUPP;
2725 			break;
2726 		}
2727 		error = sooptcopyin(sopt, &vifi, sizeof(int), sizeof(int));
2728 		if (error)
2729 			break;
2730 		if (!legal_vif_num(vifi) && (vifi != -1)) {
2731 			error = EINVAL;
2732 			break;
2733 		}
2734 		imo = inp_findmoptions(inp);
2735 		imo->imo_multicast_vif = vifi;
2736 		INP_WUNLOCK(inp);
2737 		break;
2738 	}
2739 
2740 	case IP_MULTICAST_IF:
2741 		error = inp_set_multicast_if(inp, sopt);
2742 		break;
2743 
2744 	case IP_MULTICAST_TTL: {
2745 		u_char ttl;
2746 
2747 		/*
2748 		 * Set the IP time-to-live for outgoing multicast packets.
2749 		 * The original multicast API required a char argument,
2750 		 * which is inconsistent with the rest of the socket API.
2751 		 * We allow either a char or an int.
2752 		 */
2753 		if (sopt->sopt_valsize == sizeof(u_char)) {
2754 			error = sooptcopyin(sopt, &ttl, sizeof(u_char),
2755 			    sizeof(u_char));
2756 			if (error)
2757 				break;
2758 		} else {
2759 			u_int ittl;
2760 
2761 			error = sooptcopyin(sopt, &ittl, sizeof(u_int),
2762 			    sizeof(u_int));
2763 			if (error)
2764 				break;
2765 			if (ittl > 255) {
2766 				error = EINVAL;
2767 				break;
2768 			}
2769 			ttl = (u_char)ittl;
2770 		}
2771 		imo = inp_findmoptions(inp);
2772 		imo->imo_multicast_ttl = ttl;
2773 		INP_WUNLOCK(inp);
2774 		break;
2775 	}
2776 
2777 	case IP_MULTICAST_LOOP: {
2778 		u_char loop;
2779 
2780 		/*
2781 		 * Set the loopback flag for outgoing multicast packets.
2782 		 * Must be zero or one.  The original multicast API required a
2783 		 * char argument, which is inconsistent with the rest
2784 		 * of the socket API.  We allow either a char or an int.
2785 		 */
2786 		if (sopt->sopt_valsize == sizeof(u_char)) {
2787 			error = sooptcopyin(sopt, &loop, sizeof(u_char),
2788 			    sizeof(u_char));
2789 			if (error)
2790 				break;
2791 		} else {
2792 			u_int iloop;
2793 
2794 			error = sooptcopyin(sopt, &iloop, sizeof(u_int),
2795 					    sizeof(u_int));
2796 			if (error)
2797 				break;
2798 			loop = (u_char)iloop;
2799 		}
2800 		imo = inp_findmoptions(inp);
2801 		imo->imo_multicast_loop = !!loop;
2802 		INP_WUNLOCK(inp);
2803 		break;
2804 	}
2805 
2806 	case IP_ADD_MEMBERSHIP:
2807 	case IP_ADD_SOURCE_MEMBERSHIP:
2808 	case MCAST_JOIN_GROUP:
2809 	case MCAST_JOIN_SOURCE_GROUP:
2810 		error = inp_join_group(inp, sopt);
2811 		break;
2812 
2813 	case IP_DROP_MEMBERSHIP:
2814 	case IP_DROP_SOURCE_MEMBERSHIP:
2815 	case MCAST_LEAVE_GROUP:
2816 	case MCAST_LEAVE_SOURCE_GROUP:
2817 		error = inp_leave_group(inp, sopt);
2818 		break;
2819 
2820 	case IP_BLOCK_SOURCE:
2821 	case IP_UNBLOCK_SOURCE:
2822 	case MCAST_BLOCK_SOURCE:
2823 	case MCAST_UNBLOCK_SOURCE:
2824 		error = inp_block_unblock_source(inp, sopt);
2825 		break;
2826 
2827 	case IP_MSFILTER:
2828 		error = inp_set_source_filters(inp, sopt);
2829 		break;
2830 
2831 	default:
2832 		error = EOPNOTSUPP;
2833 		break;
2834 	}
2835 
2836 	INP_UNLOCK_ASSERT(inp);
2837 
2838 	return (error);
2839 }
2840 
2841 /*
2842  * Expose IGMP's multicast filter mode and source list(s) to userland,
2843  * keyed by (ifindex, group).
2844  * The filter mode is written out as a uint32_t, followed by
2845  * 0..n of struct in_addr.
2846  * For use by ifmcstat(8).
2847  * SMPng: NOTE: unlocked read of ifindex space.
2848  */
2849 static int
2850 sysctl_ip_mcast_filters(SYSCTL_HANDLER_ARGS)
2851 {
2852 	struct in_addr			 src, group;
2853 	struct epoch_tracker		 et;
2854 	struct ifnet			*ifp;
2855 	struct ifmultiaddr		*ifma;
2856 	struct in_multi			*inm;
2857 	struct ip_msource		*ims;
2858 	int				*name;
2859 	int				 retval;
2860 	u_int				 namelen;
2861 	uint32_t			 fmode, ifindex;
2862 
2863 	name = (int *)arg1;
2864 	namelen = arg2;
2865 
2866 	if (req->newptr != NULL)
2867 		return (EPERM);
2868 
2869 	if (namelen != 2)
2870 		return (EINVAL);
2871 
2872 	group.s_addr = name[1];
2873 	if (!IN_MULTICAST(ntohl(group.s_addr))) {
2874 		CTR2(KTR_IGMPV3, "%s: group 0x%08x is not multicast",
2875 		    __func__, ntohl(group.s_addr));
2876 		return (EINVAL);
2877 	}
2878 
2879 	ifindex = name[0];
2880 	NET_EPOCH_ENTER(et);
2881 	ifp = ifnet_byindex(ifindex);
2882 	if (ifp == NULL) {
2883 		NET_EPOCH_EXIT(et);
2884 		CTR2(KTR_IGMPV3, "%s: no ifp for ifindex %u",
2885 		    __func__, ifindex);
2886 		return (ENOENT);
2887 	}
2888 
2889 	retval = sysctl_wire_old_buffer(req,
2890 	    sizeof(uint32_t) + (in_mcast_maxgrpsrc * sizeof(struct in_addr)));
2891 	if (retval) {
2892 		NET_EPOCH_EXIT(et);
2893 		return (retval);
2894 	}
2895 
2896 	IN_MULTI_LIST_LOCK();
2897 
2898 	CK_STAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
2899 		inm = inm_ifmultiaddr_get_inm(ifma);
2900 		if (inm == NULL)
2901 			continue;
2902 		if (!in_hosteq(inm->inm_addr, group))
2903 			continue;
2904 		fmode = inm->inm_st[1].iss_fmode;
2905 		retval = SYSCTL_OUT(req, &fmode, sizeof(uint32_t));
2906 		if (retval != 0)
2907 			break;
2908 		RB_FOREACH(ims, ip_msource_tree, &inm->inm_srcs) {
2909 			CTR2(KTR_IGMPV3, "%s: visit node 0x%08x", __func__,
2910 			    ims->ims_haddr);
2911 			/*
2912 			 * Only copy-out sources which are in-mode.
2913 			 */
2914 			if (fmode != ims_get_mode(inm, ims, 1)) {
2915 				CTR1(KTR_IGMPV3, "%s: skip non-in-mode",
2916 				    __func__);
2917 				continue;
2918 			}
2919 			src.s_addr = htonl(ims->ims_haddr);
2920 			retval = SYSCTL_OUT(req, &src, sizeof(struct in_addr));
2921 			if (retval != 0)
2922 				break;
2923 		}
2924 	}
2925 
2926 	IN_MULTI_LIST_UNLOCK();
2927 	NET_EPOCH_EXIT(et);
2928 
2929 	return (retval);
2930 }
2931 
2932 #if defined(KTR) && (KTR_COMPILE & KTR_IGMPV3)
2933 
2934 static const char *inm_modestrs[] = {
2935 	[MCAST_UNDEFINED] = "un",
2936 	[MCAST_INCLUDE] = "in",
2937 	[MCAST_EXCLUDE] = "ex",
2938 };
2939 _Static_assert(MCAST_UNDEFINED == 0 &&
2940 	       MCAST_EXCLUDE + 1 == nitems(inm_modestrs),
2941 	       "inm_modestrs: no longer matches #defines");
2942 
2943 static const char *
2944 inm_mode_str(const int mode)
2945 {
2946 
2947 	if (mode >= MCAST_UNDEFINED && mode <= MCAST_EXCLUDE)
2948 		return (inm_modestrs[mode]);
2949 	return ("??");
2950 }
2951 
2952 static const char *inm_statestrs[] = {
2953 	[IGMP_NOT_MEMBER] = "not-member",
2954 	[IGMP_SILENT_MEMBER] = "silent",
2955 	[IGMP_REPORTING_MEMBER] = "reporting",
2956 	[IGMP_IDLE_MEMBER] = "idle",
2957 	[IGMP_LAZY_MEMBER] = "lazy",
2958 	[IGMP_SLEEPING_MEMBER] = "sleeping",
2959 	[IGMP_AWAKENING_MEMBER] = "awakening",
2960 	[IGMP_G_QUERY_PENDING_MEMBER] = "query-pending",
2961 	[IGMP_SG_QUERY_PENDING_MEMBER] = "sg-query-pending",
2962 	[IGMP_LEAVING_MEMBER] = "leaving",
2963 };
2964 _Static_assert(IGMP_NOT_MEMBER == 0 &&
2965 	       IGMP_LEAVING_MEMBER + 1 == nitems(inm_statestrs),
2966 	       "inm_statetrs: no longer matches #defines");
2967 
2968 static const char *
2969 inm_state_str(const int state)
2970 {
2971 
2972 	if (state >= IGMP_NOT_MEMBER && state <= IGMP_LEAVING_MEMBER)
2973 		return (inm_statestrs[state]);
2974 	return ("??");
2975 }
2976 
2977 /*
2978  * Dump an in_multi structure to the console.
2979  */
2980 void
2981 inm_print(const struct in_multi *inm)
2982 {
2983 	int t;
2984 	char addrbuf[INET_ADDRSTRLEN];
2985 
2986 	if ((ktr_mask & KTR_IGMPV3) == 0)
2987 		return;
2988 
2989 	printf("%s: --- begin inm %p ---\n", __func__, inm);
2990 	printf("addr %s ifp %p(%s) ifma %p\n",
2991 	    inet_ntoa_r(inm->inm_addr, addrbuf),
2992 	    inm->inm_ifp,
2993 	    inm->inm_ifp->if_xname,
2994 	    inm->inm_ifma);
2995 	printf("timer %u state %s refcount %u scq.len %u\n",
2996 	    inm->inm_timer,
2997 	    inm_state_str(inm->inm_state),
2998 	    inm->inm_refcount,
2999 	    inm->inm_scq.mq_len);
3000 	printf("igi %p nsrc %lu sctimer %u scrv %u\n",
3001 	    inm->inm_igi,
3002 	    inm->inm_nsrc,
3003 	    inm->inm_sctimer,
3004 	    inm->inm_scrv);
3005 	for (t = 0; t < 2; t++) {
3006 		printf("t%d: fmode %s asm %u ex %u in %u rec %u\n", t,
3007 		    inm_mode_str(inm->inm_st[t].iss_fmode),
3008 		    inm->inm_st[t].iss_asm,
3009 		    inm->inm_st[t].iss_ex,
3010 		    inm->inm_st[t].iss_in,
3011 		    inm->inm_st[t].iss_rec);
3012 	}
3013 	printf("%s: --- end inm %p ---\n", __func__, inm);
3014 }
3015 
3016 #else /* !KTR || !(KTR_COMPILE & KTR_IGMPV3) */
3017 
3018 void
3019 inm_print(const struct in_multi *inm)
3020 {
3021 
3022 }
3023 
3024 #endif /* KTR && (KTR_COMPILE & KTR_IGMPV3) */
3025 
3026 RB_GENERATE(ip_msource_tree, ip_msource, ims_link, ip_msource_cmp);
3027