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/rmlock.h>
48#include <sys/socket.h>
49#include <sys/socketvar.h>
50#include <sys/protosw.h>
51#include <sys/sysctl.h>
52#include <sys/ktr.h>
53#include <sys/taskqueue.h>
54#include <sys/tree.h>
55
56#include <net/if.h>
57#include <net/if_var.h>
58#include <net/if_dl.h>
59#include <net/route.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 <netinet/ip_var.h>
70#include <netinet/igmp_var.h>
71
72#ifndef KTR_IGMPV3
73#define KTR_IGMPV3 KTR_INET
74#endif
75
76#ifndef __SOCKUNION_DECLARED
77union sockunion {
78	struct sockaddr_storage	ss;
79	struct sockaddr		sa;
80	struct sockaddr_dl	sdl;
81	struct sockaddr_in	sin;
82};
83typedef union sockunion sockunion_t;
84#define __SOCKUNION_DECLARED
85#endif /* __SOCKUNION_DECLARED */
86
87static MALLOC_DEFINE(M_INMFILTER, "in_mfilter",
88    "IPv4 multicast PCB-layer source filter");
89static MALLOC_DEFINE(M_IPMADDR, "in_multi", "IPv4 multicast group");
90static MALLOC_DEFINE(M_IPMOPTS, "ip_moptions", "IPv4 multicast options");
91static MALLOC_DEFINE(M_IPMSOURCE, "ip_msource",
92    "IPv4 multicast IGMP-layer source filter");
93
94/*
95 * Locking:
96 *
97 * - Lock order is: Giant, IN_MULTI_LOCK, INP_WLOCK,
98 *   IN_MULTI_LIST_LOCK, IGMP_LOCK, IF_ADDR_LOCK.
99 * - The IF_ADDR_LOCK is implicitly taken by inm_lookup() earlier, however
100 *   it can be taken by code in net/if.c also.
101 * - ip_moptions and in_mfilter are covered by the INP_WLOCK.
102 *
103 * struct in_multi is covered by IN_MULTI_LIST_LOCK. There isn't strictly
104 * any need for in_multi itself to be virtualized -- it is bound to an ifp
105 * anyway no matter what happens.
106 */
107struct mtx in_multi_list_mtx;
108MTX_SYSINIT(in_multi_mtx, &in_multi_list_mtx, "in_multi_list_mtx", MTX_DEF);
109
110struct mtx in_multi_free_mtx;
111MTX_SYSINIT(in_multi_free_mtx, &in_multi_free_mtx, "in_multi_free_mtx", MTX_DEF);
112
113struct sx in_multi_sx;
114SX_SYSINIT(in_multi_sx, &in_multi_sx, "in_multi_sx");
115
116int ifma_restart;
117
118/*
119 * Functions with non-static linkage defined in this file should be
120 * declared in in_var.h:
121 *  imo_multi_filter()
122 *  in_addmulti()
123 *  in_delmulti()
124 *  in_joingroup()
125 *  in_joingroup_locked()
126 *  in_leavegroup()
127 *  in_leavegroup_locked()
128 * and ip_var.h:
129 *  inp_freemoptions()
130 *  inp_getmoptions()
131 *  inp_setmoptions()
132 *
133 * XXX: Both carp and pf need to use the legacy (*,G) KPIs in_addmulti()
134 * and in_delmulti().
135 */
136static void	imf_commit(struct in_mfilter *);
137static int	imf_get_source(struct in_mfilter *imf,
138		    const struct sockaddr_in *psin,
139		    struct in_msource **);
140static struct in_msource *
141		imf_graft(struct in_mfilter *, const uint8_t,
142		    const struct sockaddr_in *);
143static void	imf_leave(struct in_mfilter *);
144static int	imf_prune(struct in_mfilter *, const struct sockaddr_in *);
145static void	imf_purge(struct in_mfilter *);
146static void	imf_rollback(struct in_mfilter *);
147static void	imf_reap(struct in_mfilter *);
148static struct in_mfilter *
149		imo_match_group(const struct ip_moptions *,
150		    const struct ifnet *, const struct sockaddr *);
151static struct in_msource *
152		imo_match_source(struct in_mfilter *, const struct sockaddr *);
153static void	ims_merge(struct ip_msource *ims,
154		    const struct in_msource *lims, const int rollback);
155static int	in_getmulti(struct ifnet *, const struct in_addr *,
156		    struct in_multi **);
157static int	inm_get_source(struct in_multi *inm, const in_addr_t haddr,
158		    const int noalloc, struct ip_msource **pims);
159#ifdef KTR
160static int	inm_is_ifp_detached(const struct in_multi *);
161#endif
162static int	inm_merge(struct in_multi *, /*const*/ struct in_mfilter *);
163static void	inm_purge(struct in_multi *);
164static void	inm_reap(struct in_multi *);
165static void inm_release(struct in_multi *);
166static struct ip_moptions *
167		inp_findmoptions(struct inpcb *);
168static int	inp_get_source_filters(struct inpcb *, struct sockopt *);
169static int	inp_join_group(struct inpcb *, struct sockopt *);
170static int	inp_leave_group(struct inpcb *, struct sockopt *);
171static struct ifnet *
172		inp_lookup_mcast_ifp(const struct inpcb *,
173		    const struct sockaddr_in *, const struct in_addr);
174static int	inp_block_unblock_source(struct inpcb *, struct sockopt *);
175static int	inp_set_multicast_if(struct inpcb *, struct sockopt *);
176static int	inp_set_source_filters(struct inpcb *, struct sockopt *);
177static int	sysctl_ip_mcast_filters(SYSCTL_HANDLER_ARGS);
178
179static SYSCTL_NODE(_net_inet_ip, OID_AUTO, mcast, CTLFLAG_RW, 0,
180    "IPv4 multicast");
181
182static u_long in_mcast_maxgrpsrc = IP_MAX_GROUP_SRC_FILTER;
183SYSCTL_ULONG(_net_inet_ip_mcast, OID_AUTO, maxgrpsrc,
184    CTLFLAG_RWTUN, &in_mcast_maxgrpsrc, 0,
185    "Max source filters per group");
186
187static u_long in_mcast_maxsocksrc = IP_MAX_SOCK_SRC_FILTER;
188SYSCTL_ULONG(_net_inet_ip_mcast, OID_AUTO, maxsocksrc,
189    CTLFLAG_RWTUN, &in_mcast_maxsocksrc, 0,
190    "Max source filters per socket");
191
192int in_mcast_loop = IP_DEFAULT_MULTICAST_LOOP;
193SYSCTL_INT(_net_inet_ip_mcast, OID_AUTO, loop, CTLFLAG_RWTUN,
194    &in_mcast_loop, 0, "Loopback multicast datagrams by default");
195
196static SYSCTL_NODE(_net_inet_ip_mcast, OID_AUTO, filters,
197    CTLFLAG_RD | CTLFLAG_MPSAFE, sysctl_ip_mcast_filters,
198    "Per-interface stack-wide source filters");
199
200#ifdef KTR
201/*
202 * Inline function which wraps assertions for a valid ifp.
203 * The ifnet layer will set the ifma's ifp pointer to NULL if the ifp
204 * is detached.
205 */
206static int __inline
207inm_is_ifp_detached(const struct in_multi *inm)
208{
209	struct ifnet *ifp;
210
211	KASSERT(inm->inm_ifma != NULL, ("%s: no ifma", __func__));
212	ifp = inm->inm_ifma->ifma_ifp;
213	if (ifp != NULL) {
214		/*
215		 * Sanity check that netinet's notion of ifp is the
216		 * same as net's.
217		 */
218		KASSERT(inm->inm_ifp == ifp, ("%s: bad ifp", __func__));
219	}
220
221	return (ifp == NULL);
222}
223#endif
224
225/*
226 * Interface detach can happen in a taskqueue thread context, so we must use a
227 * dedicated thread to avoid deadlocks when draining inm_release tasks.
228 */
229TASKQUEUE_DEFINE_THREAD(inm_free);
230static struct in_multi_head inm_free_list = SLIST_HEAD_INITIALIZER();
231static void inm_release_task(void *arg __unused, int pending __unused);
232static struct task inm_free_task = TASK_INITIALIZER(0, inm_release_task, NULL);
233
234void
235inm_release_wait(void *arg __unused)
236{
237
238	/*
239	 * Make sure all pending multicast addresses are freed before
240	 * the VNET or network device is destroyed:
241	 */
242	taskqueue_drain(taskqueue_inm_free, &inm_free_task);
243}
244#ifdef VIMAGE
245VNET_SYSUNINIT(inm_release_wait, SI_SUB_PROTO_DOMAIN, SI_ORDER_FIRST, inm_release_wait, NULL);
246#endif
247
248void
249inm_release_list_deferred(struct in_multi_head *inmh)
250{
251
252	if (SLIST_EMPTY(inmh))
253		return;
254	mtx_lock(&in_multi_free_mtx);
255	SLIST_CONCAT(&inm_free_list, inmh, in_multi, inm_nrele);
256	mtx_unlock(&in_multi_free_mtx);
257	taskqueue_enqueue(taskqueue_inm_free, &inm_free_task);
258}
259
260void
261inm_disconnect(struct in_multi *inm)
262{
263	struct ifnet *ifp;
264	struct ifmultiaddr *ifma, *ll_ifma;
265
266	ifp = inm->inm_ifp;
267	IF_ADDR_WLOCK_ASSERT(ifp);
268	ifma = inm->inm_ifma;
269
270	if_ref(ifp);
271	if (ifma->ifma_flags & IFMA_F_ENQUEUED) {
272		CK_STAILQ_REMOVE(&ifp->if_multiaddrs, ifma, ifmultiaddr, ifma_link);
273		ifma->ifma_flags &= ~IFMA_F_ENQUEUED;
274	}
275	MCDPRINTF("removed ifma: %p from %s\n", ifma, ifp->if_xname);
276	if ((ll_ifma = ifma->ifma_llifma) != NULL) {
277		MPASS(ifma != ll_ifma);
278		ifma->ifma_llifma = NULL;
279		MPASS(ll_ifma->ifma_llifma == NULL);
280		MPASS(ll_ifma->ifma_ifp == ifp);
281		if (--ll_ifma->ifma_refcount == 0) {
282			if (ll_ifma->ifma_flags & IFMA_F_ENQUEUED) {
283				CK_STAILQ_REMOVE(&ifp->if_multiaddrs, ll_ifma, ifmultiaddr, ifma_link);
284				ll_ifma->ifma_flags &= ~IFMA_F_ENQUEUED;
285			}
286			MCDPRINTF("removed ll_ifma: %p from %s\n", ll_ifma, ifp->if_xname);
287			if_freemulti(ll_ifma);
288			ifma_restart = true;
289		}
290	}
291}
292
293void
294inm_release_deferred(struct in_multi *inm)
295{
296	struct in_multi_head tmp;
297
298	IN_MULTI_LIST_LOCK_ASSERT();
299	MPASS(inm->inm_refcount > 0);
300	if (--inm->inm_refcount == 0) {
301		SLIST_INIT(&tmp);
302		inm_disconnect(inm);
303		inm->inm_ifma->ifma_protospec = NULL;
304		SLIST_INSERT_HEAD(&tmp, inm, inm_nrele);
305		inm_release_list_deferred(&tmp);
306	}
307}
308
309static void
310inm_release_task(void *arg __unused, int pending __unused)
311{
312	struct in_multi_head inm_free_tmp;
313	struct in_multi *inm, *tinm;
314
315	SLIST_INIT(&inm_free_tmp);
316	mtx_lock(&in_multi_free_mtx);
317	SLIST_CONCAT(&inm_free_tmp, &inm_free_list, in_multi, inm_nrele);
318	mtx_unlock(&in_multi_free_mtx);
319	IN_MULTI_LOCK();
320	SLIST_FOREACH_SAFE(inm, &inm_free_tmp, inm_nrele, tinm) {
321		SLIST_REMOVE_HEAD(&inm_free_tmp, inm_nrele);
322		MPASS(inm);
323		inm_release(inm);
324	}
325	IN_MULTI_UNLOCK();
326}
327
328/*
329 * Initialize an in_mfilter structure to a known state at t0, t1
330 * with an empty source filter list.
331 */
332static __inline void
333imf_init(struct in_mfilter *imf, const int st0, const int st1)
334{
335	memset(imf, 0, sizeof(struct in_mfilter));
336	RB_INIT(&imf->imf_sources);
337	imf->imf_st[0] = st0;
338	imf->imf_st[1] = st1;
339}
340
341struct in_mfilter *
342ip_mfilter_alloc(const int mflags, const int st0, const int st1)
343{
344	struct in_mfilter *imf;
345
346	imf = malloc(sizeof(*imf), M_INMFILTER, mflags);
347	if (imf != NULL)
348		imf_init(imf, st0, st1);
349
350	return (imf);
351}
352
353void
354ip_mfilter_free(struct in_mfilter *imf)
355{
356
357	imf_purge(imf);
358	free(imf, M_INMFILTER);
359}
360
361/*
362 * Function for looking up an in_multi record for an IPv4 multicast address
363 * on a given interface. ifp must be valid. If no record found, return NULL.
364 * The IN_MULTI_LIST_LOCK and IF_ADDR_LOCK on ifp must be held.
365 */
366struct in_multi *
367inm_lookup_locked(struct ifnet *ifp, const struct in_addr ina)
368{
369	struct ifmultiaddr *ifma;
370	struct in_multi *inm;
371
372	IN_MULTI_LIST_LOCK_ASSERT();
373	IF_ADDR_LOCK_ASSERT(ifp);
374
375	inm = NULL;
376	CK_STAILQ_FOREACH(ifma, &((ifp)->if_multiaddrs), ifma_link) {
377		if (ifma->ifma_addr->sa_family != AF_INET ||
378			ifma->ifma_protospec == NULL)
379			continue;
380		inm = (struct in_multi *)ifma->ifma_protospec;
381		if (inm->inm_addr.s_addr == ina.s_addr)
382			break;
383		inm = NULL;
384	}
385	return (inm);
386}
387
388/*
389 * Wrapper for inm_lookup_locked().
390 * The IF_ADDR_LOCK will be taken on ifp and released on return.
391 */
392struct in_multi *
393inm_lookup(struct ifnet *ifp, const struct in_addr ina)
394{
395	struct in_multi *inm;
396
397	IN_MULTI_LIST_LOCK_ASSERT();
398	IF_ADDR_RLOCK(ifp);
399	inm = inm_lookup_locked(ifp, ina);
400	IF_ADDR_RUNLOCK(ifp);
401
402	return (inm);
403}
404
405/*
406 * Find an IPv4 multicast group entry for this ip_moptions instance
407 * which matches the specified group, and optionally an interface.
408 * Return its index into the array, or -1 if not found.
409 */
410static struct in_mfilter *
411imo_match_group(const struct ip_moptions *imo, const struct ifnet *ifp,
412    const struct sockaddr *group)
413{
414	const struct sockaddr_in *gsin;
415	struct in_mfilter *imf;
416	struct in_multi	*inm;
417
418	gsin = (const struct sockaddr_in *)group;
419
420	IP_MFILTER_FOREACH(imf, &imo->imo_head) {
421		inm = imf->imf_inm;
422		if (inm == NULL)
423			continue;
424		if ((ifp == NULL || (inm->inm_ifp == ifp)) &&
425		    in_hosteq(inm->inm_addr, gsin->sin_addr)) {
426			break;
427		}
428	}
429	return (imf);
430}
431
432/*
433 * Find an IPv4 multicast source entry for this imo which matches
434 * the given group index for this socket, and source address.
435 *
436 * NOTE: This does not check if the entry is in-mode, merely if
437 * it exists, which may not be the desired behaviour.
438 */
439static struct in_msource *
440imo_match_source(struct in_mfilter *imf, const struct sockaddr *src)
441{
442	struct ip_msource	 find;
443	struct ip_msource	*ims;
444	const sockunion_t	*psa;
445
446	KASSERT(src->sa_family == AF_INET, ("%s: !AF_INET", __func__));
447
448	/* Source trees are keyed in host byte order. */
449	psa = (const sockunion_t *)src;
450	find.ims_haddr = ntohl(psa->sin.sin_addr.s_addr);
451	ims = RB_FIND(ip_msource_tree, &imf->imf_sources, &find);
452
453	return ((struct in_msource *)ims);
454}
455
456/*
457 * Perform filtering for multicast datagrams on a socket by group and source.
458 *
459 * Returns 0 if a datagram should be allowed through, or various error codes
460 * if the socket was not a member of the group, or the source was muted, etc.
461 */
462int
463imo_multi_filter(const struct ip_moptions *imo, const struct ifnet *ifp,
464    const struct sockaddr *group, const struct sockaddr *src)
465{
466	struct in_mfilter *imf;
467	struct in_msource *ims;
468	int mode;
469
470	KASSERT(ifp != NULL, ("%s: null ifp", __func__));
471
472	imf = imo_match_group(imo, ifp, group);
473	if (imf == NULL)
474		return (MCAST_NOTGMEMBER);
475
476	/*
477	 * Check if the source was included in an (S,G) join.
478	 * Allow reception on exclusive memberships by default,
479	 * reject reception on inclusive memberships by default.
480	 * Exclude source only if an in-mode exclude filter exists.
481	 * Include source only if an in-mode include filter exists.
482	 * NOTE: We are comparing group state here at IGMP t1 (now)
483	 * with socket-layer t0 (since last downcall).
484	 */
485	mode = imf->imf_st[1];
486	ims = imo_match_source(imf, src);
487
488	if ((ims == NULL && mode == MCAST_INCLUDE) ||
489	    (ims != NULL && ims->imsl_st[0] != mode))
490		return (MCAST_NOTSMEMBER);
491
492	return (MCAST_PASS);
493}
494
495/*
496 * Find and return a reference to an in_multi record for (ifp, group),
497 * and bump its reference count.
498 * If one does not exist, try to allocate it, and update link-layer multicast
499 * filters on ifp to listen for group.
500 * Assumes the IN_MULTI lock is held across the call.
501 * Return 0 if successful, otherwise return an appropriate error code.
502 */
503static int
504in_getmulti(struct ifnet *ifp, const struct in_addr *group,
505    struct in_multi **pinm)
506{
507	struct sockaddr_in	 gsin;
508	struct ifmultiaddr	*ifma;
509	struct in_ifinfo	*ii;
510	struct in_multi		*inm;
511	int error;
512
513	IN_MULTI_LOCK_ASSERT();
514
515	ii = (struct in_ifinfo *)ifp->if_afdata[AF_INET];
516	IN_MULTI_LIST_LOCK();
517	inm = inm_lookup(ifp, *group);
518	if (inm != NULL) {
519		/*
520		 * If we already joined this group, just bump the
521		 * refcount and return it.
522		 */
523		KASSERT(inm->inm_refcount >= 1,
524		    ("%s: bad refcount %d", __func__, inm->inm_refcount));
525		inm_acquire_locked(inm);
526		*pinm = inm;
527	}
528	IN_MULTI_LIST_UNLOCK();
529	if (inm != NULL)
530		return (0);
531
532	memset(&gsin, 0, sizeof(gsin));
533	gsin.sin_family = AF_INET;
534	gsin.sin_len = sizeof(struct sockaddr_in);
535	gsin.sin_addr = *group;
536
537	/*
538	 * Check if a link-layer group is already associated
539	 * with this network-layer group on the given ifnet.
540	 */
541	error = if_addmulti(ifp, (struct sockaddr *)&gsin, &ifma);
542	if (error != 0)
543		return (error);
544
545	/* XXX ifma_protospec must be covered by IF_ADDR_LOCK */
546	IN_MULTI_LIST_LOCK();
547	IF_ADDR_WLOCK(ifp);
548
549	/*
550	 * If something other than netinet is occupying the link-layer
551	 * group, print a meaningful error message and back out of
552	 * the allocation.
553	 * Otherwise, bump the refcount on the existing network-layer
554	 * group association and return it.
555	 */
556	if (ifma->ifma_protospec != NULL) {
557		inm = (struct in_multi *)ifma->ifma_protospec;
558#ifdef INVARIANTS
559		KASSERT(ifma->ifma_addr != NULL, ("%s: no ifma_addr",
560		    __func__));
561		KASSERT(ifma->ifma_addr->sa_family == AF_INET,
562		    ("%s: ifma not AF_INET", __func__));
563		KASSERT(inm != NULL, ("%s: no ifma_protospec", __func__));
564		if (inm->inm_ifma != ifma || inm->inm_ifp != ifp ||
565		    !in_hosteq(inm->inm_addr, *group)) {
566			char addrbuf[INET_ADDRSTRLEN];
567
568			panic("%s: ifma %p is inconsistent with %p (%s)",
569			    __func__, ifma, inm, inet_ntoa_r(*group, addrbuf));
570		}
571#endif
572		inm_acquire_locked(inm);
573		*pinm = inm;
574		goto out_locked;
575	}
576
577	IF_ADDR_WLOCK_ASSERT(ifp);
578
579	/*
580	 * A new in_multi record is needed; allocate and initialize it.
581	 * We DO NOT perform an IGMP join as the in_ layer may need to
582	 * push an initial source list down to IGMP to support SSM.
583	 *
584	 * The initial source filter state is INCLUDE, {} as per the RFC.
585	 */
586	inm = malloc(sizeof(*inm), M_IPMADDR, M_NOWAIT | M_ZERO);
587	if (inm == NULL) {
588		IF_ADDR_WUNLOCK(ifp);
589		IN_MULTI_LIST_UNLOCK();
590		if_delmulti_ifma(ifma);
591		return (ENOMEM);
592	}
593	inm->inm_addr = *group;
594	inm->inm_ifp = ifp;
595	inm->inm_igi = ii->ii_igmp;
596	inm->inm_ifma = ifma;
597	inm->inm_refcount = 1;
598	inm->inm_state = IGMP_NOT_MEMBER;
599	mbufq_init(&inm->inm_scq, IGMP_MAX_STATE_CHANGES);
600	inm->inm_st[0].iss_fmode = MCAST_UNDEFINED;
601	inm->inm_st[1].iss_fmode = MCAST_UNDEFINED;
602	RB_INIT(&inm->inm_srcs);
603
604	ifma->ifma_protospec = inm;
605
606	*pinm = inm;
607 out_locked:
608	IF_ADDR_WUNLOCK(ifp);
609	IN_MULTI_LIST_UNLOCK();
610	return (0);
611}
612
613/*
614 * Drop a reference to an in_multi record.
615 *
616 * If the refcount drops to 0, free the in_multi record and
617 * delete the underlying link-layer membership.
618 */
619static void
620inm_release(struct in_multi *inm)
621{
622	struct ifmultiaddr *ifma;
623	struct ifnet *ifp;
624
625	CTR2(KTR_IGMPV3, "%s: refcount is %d", __func__, inm->inm_refcount);
626	MPASS(inm->inm_refcount == 0);
627	CTR2(KTR_IGMPV3, "%s: freeing inm %p", __func__, inm);
628
629	ifma = inm->inm_ifma;
630	ifp = inm->inm_ifp;
631
632	/* XXX this access is not covered by IF_ADDR_LOCK */
633	CTR2(KTR_IGMPV3, "%s: purging ifma %p", __func__, ifma);
634	if (ifp != NULL) {
635		CURVNET_SET(ifp->if_vnet);
636		inm_purge(inm);
637		free(inm, M_IPMADDR);
638		if_delmulti_ifma_flags(ifma, 1);
639		CURVNET_RESTORE();
640		if_rele(ifp);
641	} else {
642		inm_purge(inm);
643		free(inm, M_IPMADDR);
644		if_delmulti_ifma_flags(ifma, 1);
645	}
646}
647
648/*
649 * Clear recorded source entries for a group.
650 * Used by the IGMP code. Caller must hold the IN_MULTI lock.
651 * FIXME: Should reap.
652 */
653void
654inm_clear_recorded(struct in_multi *inm)
655{
656	struct ip_msource	*ims;
657
658	IN_MULTI_LIST_LOCK_ASSERT();
659
660	RB_FOREACH(ims, ip_msource_tree, &inm->inm_srcs) {
661		if (ims->ims_stp) {
662			ims->ims_stp = 0;
663			--inm->inm_st[1].iss_rec;
664		}
665	}
666	KASSERT(inm->inm_st[1].iss_rec == 0,
667	    ("%s: iss_rec %d not 0", __func__, inm->inm_st[1].iss_rec));
668}
669
670/*
671 * Record a source as pending for a Source-Group IGMPv3 query.
672 * This lives here as it modifies the shared tree.
673 *
674 * inm is the group descriptor.
675 * naddr is the address of the source to record in network-byte order.
676 *
677 * If the net.inet.igmp.sgalloc sysctl is non-zero, we will
678 * lazy-allocate a source node in response to an SG query.
679 * Otherwise, no allocation is performed. This saves some memory
680 * with the trade-off that the source will not be reported to the
681 * router if joined in the window between the query response and
682 * the group actually being joined on the local host.
683 *
684 * VIMAGE: XXX: Currently the igmp_sgalloc feature has been removed.
685 * This turns off the allocation of a recorded source entry if
686 * the group has not been joined.
687 *
688 * Return 0 if the source didn't exist or was already marked as recorded.
689 * Return 1 if the source was marked as recorded by this function.
690 * Return <0 if any error occurred (negated errno code).
691 */
692int
693inm_record_source(struct in_multi *inm, const in_addr_t naddr)
694{
695	struct ip_msource	 find;
696	struct ip_msource	*ims, *nims;
697
698	IN_MULTI_LIST_LOCK_ASSERT();
699
700	find.ims_haddr = ntohl(naddr);
701	ims = RB_FIND(ip_msource_tree, &inm->inm_srcs, &find);
702	if (ims && ims->ims_stp)
703		return (0);
704	if (ims == NULL) {
705		if (inm->inm_nsrc == in_mcast_maxgrpsrc)
706			return (-ENOSPC);
707		nims = malloc(sizeof(struct ip_msource), M_IPMSOURCE,
708		    M_NOWAIT | M_ZERO);
709		if (nims == NULL)
710			return (-ENOMEM);
711		nims->ims_haddr = find.ims_haddr;
712		RB_INSERT(ip_msource_tree, &inm->inm_srcs, nims);
713		++inm->inm_nsrc;
714		ims = nims;
715	}
716
717	/*
718	 * Mark the source as recorded and update the recorded
719	 * source count.
720	 */
721	++ims->ims_stp;
722	++inm->inm_st[1].iss_rec;
723
724	return (1);
725}
726
727/*
728 * Return a pointer to an in_msource owned by an in_mfilter,
729 * given its source address.
730 * Lazy-allocate if needed. If this is a new entry its filter state is
731 * undefined at t0.
732 *
733 * imf is the filter set being modified.
734 * haddr is the source address in *host* byte-order.
735 *
736 * SMPng: May be called with locks held; malloc must not block.
737 */
738static int
739imf_get_source(struct in_mfilter *imf, const struct sockaddr_in *psin,
740    struct in_msource **plims)
741{
742	struct ip_msource	 find;
743	struct ip_msource	*ims, *nims;
744	struct in_msource	*lims;
745	int			 error;
746
747	error = 0;
748	ims = NULL;
749	lims = NULL;
750
751	/* key is host byte order */
752	find.ims_haddr = ntohl(psin->sin_addr.s_addr);
753	ims = RB_FIND(ip_msource_tree, &imf->imf_sources, &find);
754	lims = (struct in_msource *)ims;
755	if (lims == NULL) {
756		if (imf->imf_nsrc == in_mcast_maxsocksrc)
757			return (ENOSPC);
758		nims = malloc(sizeof(struct in_msource), M_INMFILTER,
759		    M_NOWAIT | M_ZERO);
760		if (nims == NULL)
761			return (ENOMEM);
762		lims = (struct in_msource *)nims;
763		lims->ims_haddr = find.ims_haddr;
764		lims->imsl_st[0] = MCAST_UNDEFINED;
765		RB_INSERT(ip_msource_tree, &imf->imf_sources, nims);
766		++imf->imf_nsrc;
767	}
768
769	*plims = lims;
770
771	return (error);
772}
773
774/*
775 * Graft a source entry into an existing socket-layer filter set,
776 * maintaining any required invariants and checking allocations.
777 *
778 * The source is marked as being in the new filter mode at t1.
779 *
780 * Return the pointer to the new node, otherwise return NULL.
781 */
782static struct in_msource *
783imf_graft(struct in_mfilter *imf, const uint8_t st1,
784    const struct sockaddr_in *psin)
785{
786	struct ip_msource	*nims;
787	struct in_msource	*lims;
788
789	nims = malloc(sizeof(struct in_msource), M_INMFILTER,
790	    M_NOWAIT | M_ZERO);
791	if (nims == NULL)
792		return (NULL);
793	lims = (struct in_msource *)nims;
794	lims->ims_haddr = ntohl(psin->sin_addr.s_addr);
795	lims->imsl_st[0] = MCAST_UNDEFINED;
796	lims->imsl_st[1] = st1;
797	RB_INSERT(ip_msource_tree, &imf->imf_sources, nims);
798	++imf->imf_nsrc;
799
800	return (lims);
801}
802
803/*
804 * Prune a source entry from an existing socket-layer filter set,
805 * maintaining any required invariants and checking allocations.
806 *
807 * The source is marked as being left at t1, it is not freed.
808 *
809 * Return 0 if no error occurred, otherwise return an errno value.
810 */
811static int
812imf_prune(struct in_mfilter *imf, const struct sockaddr_in *psin)
813{
814	struct ip_msource	 find;
815	struct ip_msource	*ims;
816	struct in_msource	*lims;
817
818	/* key is host byte order */
819	find.ims_haddr = ntohl(psin->sin_addr.s_addr);
820	ims = RB_FIND(ip_msource_tree, &imf->imf_sources, &find);
821	if (ims == NULL)
822		return (ENOENT);
823	lims = (struct in_msource *)ims;
824	lims->imsl_st[1] = MCAST_UNDEFINED;
825	return (0);
826}
827
828/*
829 * Revert socket-layer filter set deltas at t1 to t0 state.
830 */
831static void
832imf_rollback(struct in_mfilter *imf)
833{
834	struct ip_msource	*ims, *tims;
835	struct in_msource	*lims;
836
837	RB_FOREACH_SAFE(ims, ip_msource_tree, &imf->imf_sources, tims) {
838		lims = (struct in_msource *)ims;
839		if (lims->imsl_st[0] == lims->imsl_st[1]) {
840			/* no change at t1 */
841			continue;
842		} else if (lims->imsl_st[0] != MCAST_UNDEFINED) {
843			/* revert change to existing source at t1 */
844			lims->imsl_st[1] = lims->imsl_st[0];
845		} else {
846			/* revert source added t1 */
847			CTR2(KTR_IGMPV3, "%s: free ims %p", __func__, ims);
848			RB_REMOVE(ip_msource_tree, &imf->imf_sources, ims);
849			free(ims, M_INMFILTER);
850			imf->imf_nsrc--;
851		}
852	}
853	imf->imf_st[1] = imf->imf_st[0];
854}
855
856/*
857 * Mark socket-layer filter set as INCLUDE {} at t1.
858 */
859static void
860imf_leave(struct in_mfilter *imf)
861{
862	struct ip_msource	*ims;
863	struct in_msource	*lims;
864
865	RB_FOREACH(ims, ip_msource_tree, &imf->imf_sources) {
866		lims = (struct in_msource *)ims;
867		lims->imsl_st[1] = MCAST_UNDEFINED;
868	}
869	imf->imf_st[1] = MCAST_INCLUDE;
870}
871
872/*
873 * Mark socket-layer filter set deltas as committed.
874 */
875static void
876imf_commit(struct in_mfilter *imf)
877{
878	struct ip_msource	*ims;
879	struct in_msource	*lims;
880
881	RB_FOREACH(ims, ip_msource_tree, &imf->imf_sources) {
882		lims = (struct in_msource *)ims;
883		lims->imsl_st[0] = lims->imsl_st[1];
884	}
885	imf->imf_st[0] = imf->imf_st[1];
886}
887
888/*
889 * Reap unreferenced sources from socket-layer filter set.
890 */
891static void
892imf_reap(struct in_mfilter *imf)
893{
894	struct ip_msource	*ims, *tims;
895	struct in_msource	*lims;
896
897	RB_FOREACH_SAFE(ims, ip_msource_tree, &imf->imf_sources, tims) {
898		lims = (struct in_msource *)ims;
899		if ((lims->imsl_st[0] == MCAST_UNDEFINED) &&
900		    (lims->imsl_st[1] == MCAST_UNDEFINED)) {
901			CTR2(KTR_IGMPV3, "%s: free lims %p", __func__, ims);
902			RB_REMOVE(ip_msource_tree, &imf->imf_sources, ims);
903			free(ims, M_INMFILTER);
904			imf->imf_nsrc--;
905		}
906	}
907}
908
909/*
910 * Purge socket-layer filter set.
911 */
912static void
913imf_purge(struct in_mfilter *imf)
914{
915	struct ip_msource	*ims, *tims;
916
917	RB_FOREACH_SAFE(ims, ip_msource_tree, &imf->imf_sources, tims) {
918		CTR2(KTR_IGMPV3, "%s: free ims %p", __func__, ims);
919		RB_REMOVE(ip_msource_tree, &imf->imf_sources, ims);
920		free(ims, M_INMFILTER);
921		imf->imf_nsrc--;
922	}
923	imf->imf_st[0] = imf->imf_st[1] = MCAST_UNDEFINED;
924	KASSERT(RB_EMPTY(&imf->imf_sources),
925	    ("%s: imf_sources not empty", __func__));
926}
927
928/*
929 * Look up a source filter entry for a multicast group.
930 *
931 * inm is the group descriptor to work with.
932 * haddr is the host-byte-order IPv4 address to look up.
933 * noalloc may be non-zero to suppress allocation of sources.
934 * *pims will be set to the address of the retrieved or allocated source.
935 *
936 * SMPng: NOTE: may be called with locks held.
937 * Return 0 if successful, otherwise return a non-zero error code.
938 */
939static int
940inm_get_source(struct in_multi *inm, const in_addr_t haddr,
941    const int noalloc, struct ip_msource **pims)
942{
943	struct ip_msource	 find;
944	struct ip_msource	*ims, *nims;
945
946	find.ims_haddr = haddr;
947	ims = RB_FIND(ip_msource_tree, &inm->inm_srcs, &find);
948	if (ims == NULL && !noalloc) {
949		if (inm->inm_nsrc == in_mcast_maxgrpsrc)
950			return (ENOSPC);
951		nims = malloc(sizeof(struct ip_msource), M_IPMSOURCE,
952		    M_NOWAIT | M_ZERO);
953		if (nims == NULL)
954			return (ENOMEM);
955		nims->ims_haddr = haddr;
956		RB_INSERT(ip_msource_tree, &inm->inm_srcs, nims);
957		++inm->inm_nsrc;
958		ims = nims;
959#ifdef KTR
960		CTR3(KTR_IGMPV3, "%s: allocated 0x%08x as %p", __func__,
961		    haddr, ims);
962#endif
963	}
964
965	*pims = ims;
966	return (0);
967}
968
969/*
970 * Merge socket-layer source into IGMP-layer source.
971 * If rollback is non-zero, perform the inverse of the merge.
972 */
973static void
974ims_merge(struct ip_msource *ims, const struct in_msource *lims,
975    const int rollback)
976{
977	int n = rollback ? -1 : 1;
978
979	if (lims->imsl_st[0] == MCAST_EXCLUDE) {
980		CTR3(KTR_IGMPV3, "%s: t1 ex -= %d on 0x%08x",
981		    __func__, n, ims->ims_haddr);
982		ims->ims_st[1].ex -= n;
983	} else if (lims->imsl_st[0] == MCAST_INCLUDE) {
984		CTR3(KTR_IGMPV3, "%s: t1 in -= %d on 0x%08x",
985		    __func__, n, ims->ims_haddr);
986		ims->ims_st[1].in -= n;
987	}
988
989	if (lims->imsl_st[1] == MCAST_EXCLUDE) {
990		CTR3(KTR_IGMPV3, "%s: t1 ex += %d on 0x%08x",
991		    __func__, n, ims->ims_haddr);
992		ims->ims_st[1].ex += n;
993	} else if (lims->imsl_st[1] == MCAST_INCLUDE) {
994		CTR3(KTR_IGMPV3, "%s: t1 in += %d on 0x%08x",
995		    __func__, n, ims->ims_haddr);
996		ims->ims_st[1].in += n;
997	}
998}
999
1000/*
1001 * Atomically update the global in_multi state, when a membership's
1002 * filter list is being updated in any way.
1003 *
1004 * imf is the per-inpcb-membership group filter pointer.
1005 * A fake imf may be passed for in-kernel consumers.
1006 *
1007 * XXX This is a candidate for a set-symmetric-difference style loop
1008 * which would eliminate the repeated lookup from root of ims nodes,
1009 * as they share the same key space.
1010 *
1011 * If any error occurred this function will back out of refcounts
1012 * and return a non-zero value.
1013 */
1014static int
1015inm_merge(struct in_multi *inm, /*const*/ struct in_mfilter *imf)
1016{
1017	struct ip_msource	*ims, *nims;
1018	struct in_msource	*lims;
1019	int			 schanged, error;
1020	int			 nsrc0, nsrc1;
1021
1022	schanged = 0;
1023	error = 0;
1024	nsrc1 = nsrc0 = 0;
1025	IN_MULTI_LIST_LOCK_ASSERT();
1026
1027	/*
1028	 * Update the source filters first, as this may fail.
1029	 * Maintain count of in-mode filters at t0, t1. These are
1030	 * used to work out if we transition into ASM mode or not.
1031	 * Maintain a count of source filters whose state was
1032	 * actually modified by this operation.
1033	 */
1034	RB_FOREACH(ims, ip_msource_tree, &imf->imf_sources) {
1035		lims = (struct in_msource *)ims;
1036		if (lims->imsl_st[0] == imf->imf_st[0]) nsrc0++;
1037		if (lims->imsl_st[1] == imf->imf_st[1]) nsrc1++;
1038		if (lims->imsl_st[0] == lims->imsl_st[1]) continue;
1039		error = inm_get_source(inm, lims->ims_haddr, 0, &nims);
1040		++schanged;
1041		if (error)
1042			break;
1043		ims_merge(nims, lims, 0);
1044	}
1045	if (error) {
1046		struct ip_msource *bims;
1047
1048		RB_FOREACH_REVERSE_FROM(ims, ip_msource_tree, nims) {
1049			lims = (struct in_msource *)ims;
1050			if (lims->imsl_st[0] == lims->imsl_st[1])
1051				continue;
1052			(void)inm_get_source(inm, lims->ims_haddr, 1, &bims);
1053			if (bims == NULL)
1054				continue;
1055			ims_merge(bims, lims, 1);
1056		}
1057		goto out_reap;
1058	}
1059
1060	CTR3(KTR_IGMPV3, "%s: imf filters in-mode: %d at t0, %d at t1",
1061	    __func__, nsrc0, nsrc1);
1062
1063	/* Handle transition between INCLUDE {n} and INCLUDE {} on socket. */
1064	if (imf->imf_st[0] == imf->imf_st[1] &&
1065	    imf->imf_st[1] == MCAST_INCLUDE) {
1066		if (nsrc1 == 0) {
1067			CTR1(KTR_IGMPV3, "%s: --in on inm at t1", __func__);
1068			--inm->inm_st[1].iss_in;
1069		}
1070	}
1071
1072	/* Handle filter mode transition on socket. */
1073	if (imf->imf_st[0] != imf->imf_st[1]) {
1074		CTR3(KTR_IGMPV3, "%s: imf transition %d to %d",
1075		    __func__, imf->imf_st[0], imf->imf_st[1]);
1076
1077		if (imf->imf_st[0] == MCAST_EXCLUDE) {
1078			CTR1(KTR_IGMPV3, "%s: --ex on inm at t1", __func__);
1079			--inm->inm_st[1].iss_ex;
1080		} else if (imf->imf_st[0] == MCAST_INCLUDE) {
1081			CTR1(KTR_IGMPV3, "%s: --in on inm at t1", __func__);
1082			--inm->inm_st[1].iss_in;
1083		}
1084
1085		if (imf->imf_st[1] == MCAST_EXCLUDE) {
1086			CTR1(KTR_IGMPV3, "%s: ex++ on inm at t1", __func__);
1087			inm->inm_st[1].iss_ex++;
1088		} else if (imf->imf_st[1] == MCAST_INCLUDE && nsrc1 > 0) {
1089			CTR1(KTR_IGMPV3, "%s: in++ on inm at t1", __func__);
1090			inm->inm_st[1].iss_in++;
1091		}
1092	}
1093
1094	/*
1095	 * Track inm filter state in terms of listener counts.
1096	 * If there are any exclusive listeners, stack-wide
1097	 * membership is exclusive.
1098	 * Otherwise, if only inclusive listeners, stack-wide is inclusive.
1099	 * If no listeners remain, state is undefined at t1,
1100	 * and the IGMP lifecycle for this group should finish.
1101	 */
1102	if (inm->inm_st[1].iss_ex > 0) {
1103		CTR1(KTR_IGMPV3, "%s: transition to EX", __func__);
1104		inm->inm_st[1].iss_fmode = MCAST_EXCLUDE;
1105	} else if (inm->inm_st[1].iss_in > 0) {
1106		CTR1(KTR_IGMPV3, "%s: transition to IN", __func__);
1107		inm->inm_st[1].iss_fmode = MCAST_INCLUDE;
1108	} else {
1109		CTR1(KTR_IGMPV3, "%s: transition to UNDEF", __func__);
1110		inm->inm_st[1].iss_fmode = MCAST_UNDEFINED;
1111	}
1112
1113	/* Decrement ASM listener count on transition out of ASM mode. */
1114	if (imf->imf_st[0] == MCAST_EXCLUDE && nsrc0 == 0) {
1115		if ((imf->imf_st[1] != MCAST_EXCLUDE) ||
1116		    (imf->imf_st[1] == MCAST_EXCLUDE && nsrc1 > 0)) {
1117			CTR1(KTR_IGMPV3, "%s: --asm on inm at t1", __func__);
1118			--inm->inm_st[1].iss_asm;
1119		}
1120	}
1121
1122	/* Increment ASM listener count on transition to ASM mode. */
1123	if (imf->imf_st[1] == MCAST_EXCLUDE && nsrc1 == 0) {
1124		CTR1(KTR_IGMPV3, "%s: asm++ on inm at t1", __func__);
1125		inm->inm_st[1].iss_asm++;
1126	}
1127
1128	CTR3(KTR_IGMPV3, "%s: merged imf %p to inm %p", __func__, imf, inm);
1129	inm_print(inm);
1130
1131out_reap:
1132	if (schanged > 0) {
1133		CTR1(KTR_IGMPV3, "%s: sources changed; reaping", __func__);
1134		inm_reap(inm);
1135	}
1136	return (error);
1137}
1138
1139/*
1140 * Mark an in_multi's filter set deltas as committed.
1141 * Called by IGMP after a state change has been enqueued.
1142 */
1143void
1144inm_commit(struct in_multi *inm)
1145{
1146	struct ip_msource	*ims;
1147
1148	CTR2(KTR_IGMPV3, "%s: commit inm %p", __func__, inm);
1149	CTR1(KTR_IGMPV3, "%s: pre commit:", __func__);
1150	inm_print(inm);
1151
1152	RB_FOREACH(ims, ip_msource_tree, &inm->inm_srcs) {
1153		ims->ims_st[0] = ims->ims_st[1];
1154	}
1155	inm->inm_st[0] = inm->inm_st[1];
1156}
1157
1158/*
1159 * Reap unreferenced nodes from an in_multi's filter set.
1160 */
1161static void
1162inm_reap(struct in_multi *inm)
1163{
1164	struct ip_msource	*ims, *tims;
1165
1166	RB_FOREACH_SAFE(ims, ip_msource_tree, &inm->inm_srcs, tims) {
1167		if (ims->ims_st[0].ex > 0 || ims->ims_st[0].in > 0 ||
1168		    ims->ims_st[1].ex > 0 || ims->ims_st[1].in > 0 ||
1169		    ims->ims_stp != 0)
1170			continue;
1171		CTR2(KTR_IGMPV3, "%s: free ims %p", __func__, ims);
1172		RB_REMOVE(ip_msource_tree, &inm->inm_srcs, ims);
1173		free(ims, M_IPMSOURCE);
1174		inm->inm_nsrc--;
1175	}
1176}
1177
1178/*
1179 * Purge all source nodes from an in_multi's filter set.
1180 */
1181static void
1182inm_purge(struct in_multi *inm)
1183{
1184	struct ip_msource	*ims, *tims;
1185
1186	RB_FOREACH_SAFE(ims, ip_msource_tree, &inm->inm_srcs, tims) {
1187		CTR2(KTR_IGMPV3, "%s: free ims %p", __func__, ims);
1188		RB_REMOVE(ip_msource_tree, &inm->inm_srcs, ims);
1189		free(ims, M_IPMSOURCE);
1190		inm->inm_nsrc--;
1191	}
1192}
1193
1194/*
1195 * Join a multicast group; unlocked entry point.
1196 *
1197 * SMPng: XXX: in_joingroup() is called from in_control() when Giant
1198 * is not held. Fortunately, ifp is unlikely to have been detached
1199 * at this point, so we assume it's OK to recurse.
1200 */
1201int
1202in_joingroup(struct ifnet *ifp, const struct in_addr *gina,
1203    /*const*/ struct in_mfilter *imf, struct in_multi **pinm)
1204{
1205	int error;
1206
1207	IN_MULTI_LOCK();
1208	error = in_joingroup_locked(ifp, gina, imf, pinm);
1209	IN_MULTI_UNLOCK();
1210
1211	return (error);
1212}
1213
1214/*
1215 * Join a multicast group; real entry point.
1216 *
1217 * Only preserves atomicity at inm level.
1218 * NOTE: imf argument cannot be const due to sys/tree.h limitations.
1219 *
1220 * If the IGMP downcall fails, the group is not joined, and an error
1221 * code is returned.
1222 */
1223int
1224in_joingroup_locked(struct ifnet *ifp, const struct in_addr *gina,
1225    /*const*/ struct in_mfilter *imf, struct in_multi **pinm)
1226{
1227	struct in_mfilter	 timf;
1228	struct in_multi		*inm;
1229	int			 error;
1230
1231	IN_MULTI_LOCK_ASSERT();
1232	IN_MULTI_LIST_UNLOCK_ASSERT();
1233
1234	CTR4(KTR_IGMPV3, "%s: join 0x%08x on %p(%s))", __func__,
1235	    ntohl(gina->s_addr), ifp, ifp->if_xname);
1236
1237	error = 0;
1238	inm = NULL;
1239
1240	/*
1241	 * If no imf was specified (i.e. kernel consumer),
1242	 * fake one up and assume it is an ASM join.
1243	 */
1244	if (imf == NULL) {
1245		imf_init(&timf, MCAST_UNDEFINED, MCAST_EXCLUDE);
1246		imf = &timf;
1247	}
1248
1249	error = in_getmulti(ifp, gina, &inm);
1250	if (error) {
1251		CTR1(KTR_IGMPV3, "%s: in_getmulti() failure", __func__);
1252		return (error);
1253	}
1254	IN_MULTI_LIST_LOCK();
1255	CTR1(KTR_IGMPV3, "%s: merge inm state", __func__);
1256	error = inm_merge(inm, imf);
1257	if (error) {
1258		CTR1(KTR_IGMPV3, "%s: failed to merge inm state", __func__);
1259		goto out_inm_release;
1260	}
1261
1262	CTR1(KTR_IGMPV3, "%s: doing igmp downcall", __func__);
1263	error = igmp_change_state(inm);
1264	if (error) {
1265		CTR1(KTR_IGMPV3, "%s: failed to update source", __func__);
1266		goto out_inm_release;
1267	}
1268
1269 out_inm_release:
1270	if (error) {
1271
1272		CTR2(KTR_IGMPV3, "%s: dropping ref on %p", __func__, inm);
1273		inm_release_deferred(inm);
1274	} else {
1275		*pinm = inm;
1276	}
1277	IN_MULTI_LIST_UNLOCK();
1278
1279	return (error);
1280}
1281
1282/*
1283 * Leave a multicast group; unlocked entry point.
1284 */
1285int
1286in_leavegroup(struct in_multi *inm, /*const*/ struct in_mfilter *imf)
1287{
1288	int error;
1289
1290	IN_MULTI_LOCK();
1291	error = in_leavegroup_locked(inm, imf);
1292	IN_MULTI_UNLOCK();
1293
1294	return (error);
1295}
1296
1297/*
1298 * Leave a multicast group; real entry point.
1299 * All source filters will be expunged.
1300 *
1301 * Only preserves atomicity at inm level.
1302 *
1303 * Holding the write lock for the INP which contains imf
1304 * is highly advisable. We can't assert for it as imf does not
1305 * contain a back-pointer to the owning inp.
1306 *
1307 * Note: This is not the same as inm_release(*) as this function also
1308 * makes a state change downcall into IGMP.
1309 */
1310int
1311in_leavegroup_locked(struct in_multi *inm, /*const*/ struct in_mfilter *imf)
1312{
1313	struct in_mfilter	 timf;
1314	int			 error;
1315
1316	error = 0;
1317
1318	IN_MULTI_LOCK_ASSERT();
1319	IN_MULTI_LIST_UNLOCK_ASSERT();
1320
1321	CTR5(KTR_IGMPV3, "%s: leave inm %p, 0x%08x/%s, imf %p", __func__,
1322	    inm, ntohl(inm->inm_addr.s_addr),
1323	    (inm_is_ifp_detached(inm) ? "null" : inm->inm_ifp->if_xname),
1324	    imf);
1325
1326	/*
1327	 * If no imf was specified (i.e. kernel consumer),
1328	 * fake one up and assume it is an ASM join.
1329	 */
1330	if (imf == NULL) {
1331		imf_init(&timf, MCAST_EXCLUDE, MCAST_UNDEFINED);
1332		imf = &timf;
1333	}
1334
1335	/*
1336	 * Begin state merge transaction at IGMP layer.
1337	 *
1338	 * As this particular invocation should not cause any memory
1339	 * to be allocated, and there is no opportunity to roll back
1340	 * the transaction, it MUST NOT fail.
1341	 */
1342	CTR1(KTR_IGMPV3, "%s: merge inm state", __func__);
1343	IN_MULTI_LIST_LOCK();
1344	error = inm_merge(inm, imf);
1345	KASSERT(error == 0, ("%s: failed to merge inm state", __func__));
1346
1347	CTR1(KTR_IGMPV3, "%s: doing igmp downcall", __func__);
1348	CURVNET_SET(inm->inm_ifp->if_vnet);
1349	error = igmp_change_state(inm);
1350	IF_ADDR_WLOCK(inm->inm_ifp);
1351	inm_release_deferred(inm);
1352	IF_ADDR_WUNLOCK(inm->inm_ifp);
1353	IN_MULTI_LIST_UNLOCK();
1354	CURVNET_RESTORE();
1355	if (error)
1356		CTR1(KTR_IGMPV3, "%s: failed igmp downcall", __func__);
1357
1358	CTR2(KTR_IGMPV3, "%s: dropping ref on %p", __func__, inm);
1359
1360	return (error);
1361}
1362
1363/*#ifndef BURN_BRIDGES*/
1364/*
1365 * Join an IPv4 multicast group in (*,G) exclusive mode.
1366 * The group must be a 224.0.0.0/24 link-scope group.
1367 * This KPI is for legacy kernel consumers only.
1368 */
1369struct in_multi *
1370in_addmulti(struct in_addr *ap, struct ifnet *ifp)
1371{
1372	struct in_multi *pinm;
1373	int error;
1374#ifdef INVARIANTS
1375	char addrbuf[INET_ADDRSTRLEN];
1376#endif
1377
1378	KASSERT(IN_LOCAL_GROUP(ntohl(ap->s_addr)),
1379	    ("%s: %s not in 224.0.0.0/24", __func__,
1380	    inet_ntoa_r(*ap, addrbuf)));
1381
1382	error = in_joingroup(ifp, ap, NULL, &pinm);
1383	if (error != 0)
1384		pinm = NULL;
1385
1386	return (pinm);
1387}
1388
1389/*
1390 * Block or unblock an ASM multicast source on an inpcb.
1391 * This implements the delta-based API described in RFC 3678.
1392 *
1393 * The delta-based API applies only to exclusive-mode memberships.
1394 * An IGMP downcall will be performed.
1395 *
1396 * SMPng: NOTE: Must take Giant as a join may create a new ifma.
1397 *
1398 * Return 0 if successful, otherwise return an appropriate error code.
1399 */
1400static int
1401inp_block_unblock_source(struct inpcb *inp, struct sockopt *sopt)
1402{
1403	struct group_source_req		 gsr;
1404	struct rm_priotracker		 in_ifa_tracker;
1405	sockunion_t			*gsa, *ssa;
1406	struct ifnet			*ifp;
1407	struct in_mfilter		*imf;
1408	struct ip_moptions		*imo;
1409	struct in_msource		*ims;
1410	struct in_multi			*inm;
1411	uint16_t			 fmode;
1412	int				 error, doblock;
1413
1414	ifp = NULL;
1415	error = 0;
1416	doblock = 0;
1417
1418	memset(&gsr, 0, sizeof(struct group_source_req));
1419	gsa = (sockunion_t *)&gsr.gsr_group;
1420	ssa = (sockunion_t *)&gsr.gsr_source;
1421
1422	switch (sopt->sopt_name) {
1423	case IP_BLOCK_SOURCE:
1424	case IP_UNBLOCK_SOURCE: {
1425		struct ip_mreq_source	 mreqs;
1426
1427		error = sooptcopyin(sopt, &mreqs,
1428		    sizeof(struct ip_mreq_source),
1429		    sizeof(struct ip_mreq_source));
1430		if (error)
1431			return (error);
1432
1433		gsa->sin.sin_family = AF_INET;
1434		gsa->sin.sin_len = sizeof(struct sockaddr_in);
1435		gsa->sin.sin_addr = mreqs.imr_multiaddr;
1436
1437		ssa->sin.sin_family = AF_INET;
1438		ssa->sin.sin_len = sizeof(struct sockaddr_in);
1439		ssa->sin.sin_addr = mreqs.imr_sourceaddr;
1440
1441		if (!in_nullhost(mreqs.imr_interface)) {
1442			IN_IFADDR_RLOCK(&in_ifa_tracker);
1443			INADDR_TO_IFP(mreqs.imr_interface, ifp);
1444			IN_IFADDR_RUNLOCK(&in_ifa_tracker);
1445		}
1446		if (sopt->sopt_name == IP_BLOCK_SOURCE)
1447			doblock = 1;
1448
1449		CTR3(KTR_IGMPV3, "%s: imr_interface = 0x%08x, ifp = %p",
1450		    __func__, ntohl(mreqs.imr_interface.s_addr), ifp);
1451		break;
1452	    }
1453
1454	case MCAST_BLOCK_SOURCE:
1455	case MCAST_UNBLOCK_SOURCE:
1456		error = sooptcopyin(sopt, &gsr,
1457		    sizeof(struct group_source_req),
1458		    sizeof(struct group_source_req));
1459		if (error)
1460			return (error);
1461
1462		if (gsa->sin.sin_family != AF_INET ||
1463		    gsa->sin.sin_len != sizeof(struct sockaddr_in))
1464			return (EINVAL);
1465
1466		if (ssa->sin.sin_family != AF_INET ||
1467		    ssa->sin.sin_len != sizeof(struct sockaddr_in))
1468			return (EINVAL);
1469
1470		if (gsr.gsr_interface == 0 || V_if_index < gsr.gsr_interface)
1471			return (EADDRNOTAVAIL);
1472
1473		ifp = ifnet_byindex(gsr.gsr_interface);
1474
1475		if (sopt->sopt_name == MCAST_BLOCK_SOURCE)
1476			doblock = 1;
1477		break;
1478
1479	default:
1480		CTR2(KTR_IGMPV3, "%s: unknown sopt_name %d",
1481		    __func__, sopt->sopt_name);
1482		return (EOPNOTSUPP);
1483		break;
1484	}
1485
1486	if (!IN_MULTICAST(ntohl(gsa->sin.sin_addr.s_addr)))
1487		return (EINVAL);
1488
1489	IN_MULTI_LOCK();
1490
1491	/*
1492	 * Check if we are actually a member of this group.
1493	 */
1494	imo = inp_findmoptions(inp);
1495	imf = imo_match_group(imo, ifp, &gsa->sa);
1496	if (imf == NULL) {
1497		error = EADDRNOTAVAIL;
1498		goto out_inp_locked;
1499	}
1500	inm = imf->imf_inm;
1501
1502	/*
1503	 * Attempting to use the delta-based API on an
1504	 * non exclusive-mode membership is an error.
1505	 */
1506	fmode = imf->imf_st[0];
1507	if (fmode != MCAST_EXCLUDE) {
1508		error = EINVAL;
1509		goto out_inp_locked;
1510	}
1511
1512	/*
1513	 * Deal with error cases up-front:
1514	 *  Asked to block, but already blocked; or
1515	 *  Asked to unblock, but nothing to unblock.
1516	 * If adding a new block entry, allocate it.
1517	 */
1518	ims = imo_match_source(imf, &ssa->sa);
1519	if ((ims != NULL && doblock) || (ims == NULL && !doblock)) {
1520		CTR3(KTR_IGMPV3, "%s: source 0x%08x %spresent", __func__,
1521		    ntohl(ssa->sin.sin_addr.s_addr), doblock ? "" : "not ");
1522		error = EADDRNOTAVAIL;
1523		goto out_inp_locked;
1524	}
1525
1526	INP_WLOCK_ASSERT(inp);
1527
1528	/*
1529	 * Begin state merge transaction at socket layer.
1530	 */
1531	if (doblock) {
1532		CTR2(KTR_IGMPV3, "%s: %s source", __func__, "block");
1533		ims = imf_graft(imf, fmode, &ssa->sin);
1534		if (ims == NULL)
1535			error = ENOMEM;
1536	} else {
1537		CTR2(KTR_IGMPV3, "%s: %s source", __func__, "allow");
1538		error = imf_prune(imf, &ssa->sin);
1539	}
1540
1541	if (error) {
1542		CTR1(KTR_IGMPV3, "%s: merge imf state failed", __func__);
1543		goto out_imf_rollback;
1544	}
1545
1546	/*
1547	 * Begin state merge transaction at IGMP layer.
1548	 */
1549	CTR1(KTR_IGMPV3, "%s: merge inm state", __func__);
1550	IN_MULTI_LIST_LOCK();
1551	error = inm_merge(inm, imf);
1552	if (error) {
1553		CTR1(KTR_IGMPV3, "%s: failed to merge inm state", __func__);
1554		IN_MULTI_LIST_UNLOCK();
1555		goto out_imf_rollback;
1556	}
1557
1558	CTR1(KTR_IGMPV3, "%s: doing igmp downcall", __func__);
1559	error = igmp_change_state(inm);
1560	IN_MULTI_LIST_UNLOCK();
1561	if (error)
1562		CTR1(KTR_IGMPV3, "%s: failed igmp downcall", __func__);
1563
1564out_imf_rollback:
1565	if (error)
1566		imf_rollback(imf);
1567	else
1568		imf_commit(imf);
1569
1570	imf_reap(imf);
1571
1572out_inp_locked:
1573	INP_WUNLOCK(inp);
1574	IN_MULTI_UNLOCK();
1575	return (error);
1576}
1577
1578/*
1579 * Given an inpcb, return its multicast options structure pointer.  Accepts
1580 * an unlocked inpcb pointer, but will return it locked.  May sleep.
1581 *
1582 * SMPng: NOTE: Potentially calls malloc(M_WAITOK) with Giant held.
1583 * SMPng: NOTE: Returns with the INP write lock held.
1584 */
1585static struct ip_moptions *
1586inp_findmoptions(struct inpcb *inp)
1587{
1588	struct ip_moptions	 *imo;
1589
1590	INP_WLOCK(inp);
1591	if (inp->inp_moptions != NULL)
1592		return (inp->inp_moptions);
1593
1594	INP_WUNLOCK(inp);
1595
1596	imo = malloc(sizeof(*imo), M_IPMOPTS, M_WAITOK);
1597
1598	imo->imo_multicast_ifp = NULL;
1599	imo->imo_multicast_addr.s_addr = INADDR_ANY;
1600	imo->imo_multicast_vif = -1;
1601	imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL;
1602	imo->imo_multicast_loop = in_mcast_loop;
1603	STAILQ_INIT(&imo->imo_head);
1604
1605	INP_WLOCK(inp);
1606	if (inp->inp_moptions != NULL) {
1607		free(imo, M_IPMOPTS);
1608		return (inp->inp_moptions);
1609	}
1610	inp->inp_moptions = imo;
1611	return (imo);
1612}
1613
1614static void
1615inp_gcmoptions(struct ip_moptions *imo)
1616{
1617	struct in_mfilter *imf;
1618	struct in_multi *inm;
1619	struct ifnet *ifp;
1620
1621	while ((imf = ip_mfilter_first(&imo->imo_head)) != NULL) {
1622		ip_mfilter_remove(&imo->imo_head, imf);
1623
1624		imf_leave(imf);
1625		if ((inm = imf->imf_inm) != NULL) {
1626			if ((ifp = inm->inm_ifp) != NULL) {
1627				CURVNET_SET(ifp->if_vnet);
1628				(void)in_leavegroup(inm, imf);
1629				CURVNET_RESTORE();
1630			} else {
1631				(void)in_leavegroup(inm, imf);
1632			}
1633		}
1634		ip_mfilter_free(imf);
1635	}
1636	free(imo, M_IPMOPTS);
1637}
1638
1639/*
1640 * Discard the IP multicast options (and source filters).  To minimize
1641 * the amount of work done while holding locks such as the INP's
1642 * pcbinfo lock (which is used in the receive path), the free
1643 * operation is deferred to the epoch callback task.
1644 */
1645void
1646inp_freemoptions(struct ip_moptions *imo)
1647{
1648	if (imo == NULL)
1649		return;
1650	inp_gcmoptions(imo);
1651}
1652
1653/*
1654 * Atomically get source filters on a socket for an IPv4 multicast group.
1655 * Called with INP lock held; returns with lock released.
1656 */
1657static int
1658inp_get_source_filters(struct inpcb *inp, struct sockopt *sopt)
1659{
1660	struct __msfilterreq	 msfr;
1661	sockunion_t		*gsa;
1662	struct ifnet		*ifp;
1663	struct ip_moptions	*imo;
1664	struct in_mfilter	*imf;
1665	struct ip_msource	*ims;
1666	struct in_msource	*lims;
1667	struct sockaddr_in	*psin;
1668	struct sockaddr_storage	*ptss;
1669	struct sockaddr_storage	*tss;
1670	int			 error;
1671	size_t			 nsrcs, ncsrcs;
1672
1673	INP_WLOCK_ASSERT(inp);
1674
1675	imo = inp->inp_moptions;
1676	KASSERT(imo != NULL, ("%s: null ip_moptions", __func__));
1677
1678	INP_WUNLOCK(inp);
1679
1680	error = sooptcopyin(sopt, &msfr, sizeof(struct __msfilterreq),
1681	    sizeof(struct __msfilterreq));
1682	if (error)
1683		return (error);
1684
1685	if (msfr.msfr_ifindex == 0 || V_if_index < msfr.msfr_ifindex)
1686		return (EINVAL);
1687
1688	ifp = ifnet_byindex(msfr.msfr_ifindex);
1689	if (ifp == NULL)
1690		return (EINVAL);
1691
1692	INP_WLOCK(inp);
1693
1694	/*
1695	 * Lookup group on the socket.
1696	 */
1697	gsa = (sockunion_t *)&msfr.msfr_group;
1698	imf = imo_match_group(imo, ifp, &gsa->sa);
1699	if (imf == NULL) {
1700		INP_WUNLOCK(inp);
1701		return (EADDRNOTAVAIL);
1702	}
1703
1704	/*
1705	 * Ignore memberships which are in limbo.
1706	 */
1707	if (imf->imf_st[1] == MCAST_UNDEFINED) {
1708		INP_WUNLOCK(inp);
1709		return (EAGAIN);
1710	}
1711	msfr.msfr_fmode = imf->imf_st[1];
1712
1713	/*
1714	 * If the user specified a buffer, copy out the source filter
1715	 * entries to userland gracefully.
1716	 * We only copy out the number of entries which userland
1717	 * has asked for, but we always tell userland how big the
1718	 * buffer really needs to be.
1719	 */
1720	if (msfr.msfr_nsrcs > in_mcast_maxsocksrc)
1721		msfr.msfr_nsrcs = in_mcast_maxsocksrc;
1722	tss = NULL;
1723	if (msfr.msfr_srcs != NULL && msfr.msfr_nsrcs > 0) {
1724		tss = malloc(sizeof(struct sockaddr_storage) * msfr.msfr_nsrcs,
1725		    M_TEMP, M_NOWAIT | M_ZERO);
1726		if (tss == NULL) {
1727			INP_WUNLOCK(inp);
1728			return (ENOBUFS);
1729		}
1730	}
1731
1732	/*
1733	 * Count number of sources in-mode at t0.
1734	 * If buffer space exists and remains, copy out source entries.
1735	 */
1736	nsrcs = msfr.msfr_nsrcs;
1737	ncsrcs = 0;
1738	ptss = tss;
1739	RB_FOREACH(ims, ip_msource_tree, &imf->imf_sources) {
1740		lims = (struct in_msource *)ims;
1741		if (lims->imsl_st[0] == MCAST_UNDEFINED ||
1742		    lims->imsl_st[0] != imf->imf_st[0])
1743			continue;
1744		++ncsrcs;
1745		if (tss != NULL && nsrcs > 0) {
1746			psin = (struct sockaddr_in *)ptss;
1747			psin->sin_family = AF_INET;
1748			psin->sin_len = sizeof(struct sockaddr_in);
1749			psin->sin_addr.s_addr = htonl(lims->ims_haddr);
1750			psin->sin_port = 0;
1751			++ptss;
1752			--nsrcs;
1753		}
1754	}
1755
1756	INP_WUNLOCK(inp);
1757
1758	if (tss != NULL) {
1759		error = copyout(tss, msfr.msfr_srcs,
1760		    sizeof(struct sockaddr_storage) * msfr.msfr_nsrcs);
1761		free(tss, M_TEMP);
1762		if (error)
1763			return (error);
1764	}
1765
1766	msfr.msfr_nsrcs = ncsrcs;
1767	error = sooptcopyout(sopt, &msfr, sizeof(struct __msfilterreq));
1768
1769	return (error);
1770}
1771
1772/*
1773 * Return the IP multicast options in response to user getsockopt().
1774 */
1775int
1776inp_getmoptions(struct inpcb *inp, struct sockopt *sopt)
1777{
1778	struct rm_priotracker	 in_ifa_tracker;
1779	struct ip_mreqn		 mreqn;
1780	struct ip_moptions	*imo;
1781	struct ifnet		*ifp;
1782	struct in_ifaddr	*ia;
1783	int			 error, optval;
1784	u_char			 coptval;
1785
1786	INP_WLOCK(inp);
1787	imo = inp->inp_moptions;
1788	/*
1789	 * If socket is neither of type SOCK_RAW or SOCK_DGRAM,
1790	 * or is a divert socket, reject it.
1791	 */
1792	if (inp->inp_socket->so_proto->pr_protocol == IPPROTO_DIVERT ||
1793	    (inp->inp_socket->so_proto->pr_type != SOCK_RAW &&
1794	    inp->inp_socket->so_proto->pr_type != SOCK_DGRAM)) {
1795		INP_WUNLOCK(inp);
1796		return (EOPNOTSUPP);
1797	}
1798
1799	error = 0;
1800	switch (sopt->sopt_name) {
1801	case IP_MULTICAST_VIF:
1802		if (imo != NULL)
1803			optval = imo->imo_multicast_vif;
1804		else
1805			optval = -1;
1806		INP_WUNLOCK(inp);
1807		error = sooptcopyout(sopt, &optval, sizeof(int));
1808		break;
1809
1810	case IP_MULTICAST_IF:
1811		memset(&mreqn, 0, sizeof(struct ip_mreqn));
1812		if (imo != NULL) {
1813			ifp = imo->imo_multicast_ifp;
1814			if (!in_nullhost(imo->imo_multicast_addr)) {
1815				mreqn.imr_address = imo->imo_multicast_addr;
1816			} else if (ifp != NULL) {
1817				mreqn.imr_ifindex = ifp->if_index;
1818				NET_EPOCH_ENTER();
1819				IFP_TO_IA(ifp, ia, &in_ifa_tracker);
1820				if (ia != NULL)
1821					mreqn.imr_address =
1822					    IA_SIN(ia)->sin_addr;
1823				NET_EPOCH_EXIT();
1824			}
1825		}
1826		INP_WUNLOCK(inp);
1827		if (sopt->sopt_valsize == sizeof(struct ip_mreqn)) {
1828			error = sooptcopyout(sopt, &mreqn,
1829			    sizeof(struct ip_mreqn));
1830		} else {
1831			error = sooptcopyout(sopt, &mreqn.imr_address,
1832			    sizeof(struct in_addr));
1833		}
1834		break;
1835
1836	case IP_MULTICAST_TTL:
1837		if (imo == NULL)
1838			optval = coptval = IP_DEFAULT_MULTICAST_TTL;
1839		else
1840			optval = coptval = imo->imo_multicast_ttl;
1841		INP_WUNLOCK(inp);
1842		if (sopt->sopt_valsize == sizeof(u_char))
1843			error = sooptcopyout(sopt, &coptval, sizeof(u_char));
1844		else
1845			error = sooptcopyout(sopt, &optval, sizeof(int));
1846		break;
1847
1848	case IP_MULTICAST_LOOP:
1849		if (imo == NULL)
1850			optval = coptval = IP_DEFAULT_MULTICAST_LOOP;
1851		else
1852			optval = coptval = imo->imo_multicast_loop;
1853		INP_WUNLOCK(inp);
1854		if (sopt->sopt_valsize == sizeof(u_char))
1855			error = sooptcopyout(sopt, &coptval, sizeof(u_char));
1856		else
1857			error = sooptcopyout(sopt, &optval, sizeof(int));
1858		break;
1859
1860	case IP_MSFILTER:
1861		if (imo == NULL) {
1862			error = EADDRNOTAVAIL;
1863			INP_WUNLOCK(inp);
1864		} else {
1865			error = inp_get_source_filters(inp, sopt);
1866		}
1867		break;
1868
1869	default:
1870		INP_WUNLOCK(inp);
1871		error = ENOPROTOOPT;
1872		break;
1873	}
1874
1875	INP_UNLOCK_ASSERT(inp);
1876
1877	return (error);
1878}
1879
1880/*
1881 * Look up the ifnet to use for a multicast group membership,
1882 * given the IPv4 address of an interface, and the IPv4 group address.
1883 *
1884 * This routine exists to support legacy multicast applications
1885 * which do not understand that multicast memberships are scoped to
1886 * specific physical links in the networking stack, or which need
1887 * to join link-scope groups before IPv4 addresses are configured.
1888 *
1889 * If inp is non-NULL, use this socket's current FIB number for any
1890 * required FIB lookup.
1891 * If ina is INADDR_ANY, look up the group address in the unicast FIB,
1892 * and use its ifp; usually, this points to the default next-hop.
1893 *
1894 * If the FIB lookup fails, attempt to use the first non-loopback
1895 * interface with multicast capability in the system as a
1896 * last resort. The legacy IPv4 ASM API requires that we do
1897 * this in order to allow groups to be joined when the routing
1898 * table has not yet been populated during boot.
1899 *
1900 * Returns NULL if no ifp could be found.
1901 *
1902 * FUTURE: Implement IPv4 source-address selection.
1903 */
1904static struct ifnet *
1905inp_lookup_mcast_ifp(const struct inpcb *inp,
1906    const struct sockaddr_in *gsin, const struct in_addr ina)
1907{
1908	struct rm_priotracker in_ifa_tracker;
1909	struct ifnet *ifp;
1910	struct nhop4_basic nh4;
1911	uint32_t fibnum;
1912
1913	KASSERT(gsin->sin_family == AF_INET, ("%s: not AF_INET", __func__));
1914	KASSERT(IN_MULTICAST(ntohl(gsin->sin_addr.s_addr)),
1915	    ("%s: not multicast", __func__));
1916
1917	ifp = NULL;
1918	if (!in_nullhost(ina)) {
1919		IN_IFADDR_RLOCK(&in_ifa_tracker);
1920		INADDR_TO_IFP(ina, ifp);
1921		IN_IFADDR_RUNLOCK(&in_ifa_tracker);
1922	} else {
1923		fibnum = inp ? inp->inp_inc.inc_fibnum : 0;
1924		if (fib4_lookup_nh_basic(fibnum, gsin->sin_addr, 0, 0, &nh4)==0)
1925			ifp = nh4.nh_ifp;
1926		else {
1927			struct in_ifaddr *ia;
1928			struct ifnet *mifp;
1929
1930			mifp = NULL;
1931			IN_IFADDR_RLOCK(&in_ifa_tracker);
1932			CK_STAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) {
1933				mifp = ia->ia_ifp;
1934				if (!(mifp->if_flags & IFF_LOOPBACK) &&
1935				     (mifp->if_flags & IFF_MULTICAST)) {
1936					ifp = mifp;
1937					break;
1938				}
1939			}
1940			IN_IFADDR_RUNLOCK(&in_ifa_tracker);
1941		}
1942	}
1943
1944	return (ifp);
1945}
1946
1947/*
1948 * Join an IPv4 multicast group, possibly with a source.
1949 */
1950static int
1951inp_join_group(struct inpcb *inp, struct sockopt *sopt)
1952{
1953	struct group_source_req		 gsr;
1954	sockunion_t			*gsa, *ssa;
1955	struct ifnet			*ifp;
1956	struct in_mfilter		*imf;
1957	struct ip_moptions		*imo;
1958	struct in_multi			*inm;
1959	struct in_msource		*lims;
1960	int				 error, is_new;
1961
1962	ifp = NULL;
1963	lims = NULL;
1964	error = 0;
1965
1966	memset(&gsr, 0, sizeof(struct group_source_req));
1967	gsa = (sockunion_t *)&gsr.gsr_group;
1968	gsa->ss.ss_family = AF_UNSPEC;
1969	ssa = (sockunion_t *)&gsr.gsr_source;
1970	ssa->ss.ss_family = AF_UNSPEC;
1971
1972	switch (sopt->sopt_name) {
1973	case IP_ADD_MEMBERSHIP: {
1974		struct ip_mreqn mreqn;
1975
1976		if (sopt->sopt_valsize == sizeof(struct ip_mreqn))
1977			error = sooptcopyin(sopt, &mreqn,
1978			    sizeof(struct ip_mreqn), sizeof(struct ip_mreqn));
1979		else
1980			error = sooptcopyin(sopt, &mreqn,
1981			    sizeof(struct ip_mreq), sizeof(struct ip_mreq));
1982		if (error)
1983			return (error);
1984
1985		gsa->sin.sin_family = AF_INET;
1986		gsa->sin.sin_len = sizeof(struct sockaddr_in);
1987		gsa->sin.sin_addr = mreqn.imr_multiaddr;
1988		if (!IN_MULTICAST(ntohl(gsa->sin.sin_addr.s_addr)))
1989			return (EINVAL);
1990
1991		if (sopt->sopt_valsize == sizeof(struct ip_mreqn) &&
1992		    mreqn.imr_ifindex != 0)
1993			ifp = ifnet_byindex(mreqn.imr_ifindex);
1994		else
1995			ifp = inp_lookup_mcast_ifp(inp, &gsa->sin,
1996			    mreqn.imr_address);
1997		break;
1998	}
1999	case IP_ADD_SOURCE_MEMBERSHIP: {
2000		struct ip_mreq_source	 mreqs;
2001
2002		error = sooptcopyin(sopt, &mreqs, sizeof(struct ip_mreq_source),
2003			    sizeof(struct ip_mreq_source));
2004		if (error)
2005			return (error);
2006
2007		gsa->sin.sin_family = ssa->sin.sin_family = AF_INET;
2008		gsa->sin.sin_len = ssa->sin.sin_len =
2009		    sizeof(struct sockaddr_in);
2010
2011		gsa->sin.sin_addr = mreqs.imr_multiaddr;
2012		if (!IN_MULTICAST(ntohl(gsa->sin.sin_addr.s_addr)))
2013			return (EINVAL);
2014
2015		ssa->sin.sin_addr = mreqs.imr_sourceaddr;
2016
2017		ifp = inp_lookup_mcast_ifp(inp, &gsa->sin,
2018		    mreqs.imr_interface);
2019		CTR3(KTR_IGMPV3, "%s: imr_interface = 0x%08x, ifp = %p",
2020		    __func__, ntohl(mreqs.imr_interface.s_addr), ifp);
2021		break;
2022	}
2023
2024	case MCAST_JOIN_GROUP:
2025	case MCAST_JOIN_SOURCE_GROUP:
2026		if (sopt->sopt_name == MCAST_JOIN_GROUP) {
2027			error = sooptcopyin(sopt, &gsr,
2028			    sizeof(struct group_req),
2029			    sizeof(struct group_req));
2030		} else if (sopt->sopt_name == MCAST_JOIN_SOURCE_GROUP) {
2031			error = sooptcopyin(sopt, &gsr,
2032			    sizeof(struct group_source_req),
2033			    sizeof(struct group_source_req));
2034		}
2035		if (error)
2036			return (error);
2037
2038		if (gsa->sin.sin_family != AF_INET ||
2039		    gsa->sin.sin_len != sizeof(struct sockaddr_in))
2040			return (EINVAL);
2041
2042		/*
2043		 * Overwrite the port field if present, as the sockaddr
2044		 * being copied in may be matched with a binary comparison.
2045		 */
2046		gsa->sin.sin_port = 0;
2047		if (sopt->sopt_name == MCAST_JOIN_SOURCE_GROUP) {
2048			if (ssa->sin.sin_family != AF_INET ||
2049			    ssa->sin.sin_len != sizeof(struct sockaddr_in))
2050				return (EINVAL);
2051			ssa->sin.sin_port = 0;
2052		}
2053
2054		if (!IN_MULTICAST(ntohl(gsa->sin.sin_addr.s_addr)))
2055			return (EINVAL);
2056
2057		if (gsr.gsr_interface == 0 || V_if_index < gsr.gsr_interface)
2058			return (EADDRNOTAVAIL);
2059		ifp = ifnet_byindex(gsr.gsr_interface);
2060		break;
2061
2062	default:
2063		CTR2(KTR_IGMPV3, "%s: unknown sopt_name %d",
2064		    __func__, sopt->sopt_name);
2065		return (EOPNOTSUPP);
2066		break;
2067	}
2068
2069	if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0)
2070		return (EADDRNOTAVAIL);
2071
2072	IN_MULTI_LOCK();
2073
2074	/*
2075	 * Find the membership in the membership list.
2076	 */
2077	imo = inp_findmoptions(inp);
2078	imf = imo_match_group(imo, ifp, &gsa->sa);
2079	if (imf == NULL) {
2080		is_new = 1;
2081		inm = NULL;
2082
2083		if (ip_mfilter_count(&imo->imo_head) >= IP_MAX_MEMBERSHIPS) {
2084			error = ENOMEM;
2085			goto out_inp_locked;
2086		}
2087	} else {
2088		is_new = 0;
2089		inm = imf->imf_inm;
2090
2091		if (ssa->ss.ss_family != AF_UNSPEC) {
2092			/*
2093			 * MCAST_JOIN_SOURCE_GROUP on an exclusive membership
2094			 * is an error. On an existing inclusive membership,
2095			 * it just adds the source to the filter list.
2096			 */
2097			if (imf->imf_st[1] != MCAST_INCLUDE) {
2098				error = EINVAL;
2099				goto out_inp_locked;
2100			}
2101			/*
2102			 * Throw out duplicates.
2103			 *
2104			 * XXX FIXME: This makes a naive assumption that
2105			 * even if entries exist for *ssa in this imf,
2106			 * they will be rejected as dupes, even if they
2107			 * are not valid in the current mode (in-mode).
2108			 *
2109			 * in_msource is transactioned just as for anything
2110			 * else in SSM -- but note naive use of inm_graft()
2111			 * below for allocating new filter entries.
2112			 *
2113			 * This is only an issue if someone mixes the
2114			 * full-state SSM API with the delta-based API,
2115			 * which is discouraged in the relevant RFCs.
2116			 */
2117			lims = imo_match_source(imf, &ssa->sa);
2118			if (lims != NULL /*&&
2119			    lims->imsl_st[1] == MCAST_INCLUDE*/) {
2120				error = EADDRNOTAVAIL;
2121				goto out_inp_locked;
2122			}
2123		} else {
2124			/*
2125			 * MCAST_JOIN_GROUP on an existing exclusive
2126			 * membership is an error; return EADDRINUSE
2127			 * to preserve 4.4BSD API idempotence, and
2128			 * avoid tedious detour to code below.
2129			 * NOTE: This is bending RFC 3678 a bit.
2130			 *
2131			 * On an existing inclusive membership, this is also
2132			 * an error; if you want to change filter mode,
2133			 * you must use the userland API setsourcefilter().
2134			 * XXX We don't reject this for imf in UNDEFINED
2135			 * state at t1, because allocation of a filter
2136			 * is atomic with allocation of a membership.
2137			 */
2138			error = EINVAL;
2139			if (imf->imf_st[1] == MCAST_EXCLUDE)
2140				error = EADDRINUSE;
2141			goto out_inp_locked;
2142		}
2143	}
2144
2145	/*
2146	 * Begin state merge transaction at socket layer.
2147	 */
2148	INP_WLOCK_ASSERT(inp);
2149
2150	/*
2151	 * Graft new source into filter list for this inpcb's
2152	 * membership of the group. The in_multi may not have
2153	 * been allocated yet if this is a new membership, however,
2154	 * the in_mfilter slot will be allocated and must be initialized.
2155	 *
2156	 * Note: Grafting of exclusive mode filters doesn't happen
2157	 * in this path.
2158	 * XXX: Should check for non-NULL lims (node exists but may
2159	 * not be in-mode) for interop with full-state API.
2160	 */
2161	if (ssa->ss.ss_family != AF_UNSPEC) {
2162		/* Membership starts in IN mode */
2163		if (is_new) {
2164			CTR1(KTR_IGMPV3, "%s: new join w/source", __func__);
2165			imf = ip_mfilter_alloc(M_NOWAIT, MCAST_UNDEFINED, MCAST_INCLUDE);
2166			if (imf == NULL) {
2167				error = ENOMEM;
2168				goto out_inp_locked;
2169			}
2170		} else {
2171			CTR2(KTR_IGMPV3, "%s: %s source", __func__, "allow");
2172		}
2173		lims = imf_graft(imf, MCAST_INCLUDE, &ssa->sin);
2174		if (lims == NULL) {
2175			CTR1(KTR_IGMPV3, "%s: merge imf state failed",
2176			    __func__);
2177			error = ENOMEM;
2178			goto out_inp_locked;
2179		}
2180	} else {
2181		/* No address specified; Membership starts in EX mode */
2182		if (is_new) {
2183			CTR1(KTR_IGMPV3, "%s: new join w/o source", __func__);
2184			imf = ip_mfilter_alloc(M_NOWAIT, MCAST_UNDEFINED, MCAST_EXCLUDE);
2185			if (imf == NULL) {
2186				error = ENOMEM;
2187				goto out_inp_locked;
2188			}
2189		}
2190	}
2191
2192	/*
2193	 * Begin state merge transaction at IGMP layer.
2194	 */
2195	if (is_new) {
2196		in_pcbref(inp);
2197		INP_WUNLOCK(inp);
2198
2199		error = in_joingroup_locked(ifp, &gsa->sin.sin_addr, imf,
2200		    &imf->imf_inm);
2201
2202		INP_WLOCK(inp);
2203		if (in_pcbrele_wlocked(inp)) {
2204			error = ENXIO;
2205			goto out_inp_unlocked;
2206		}
2207		if (error) {
2208                        CTR1(KTR_IGMPV3, "%s: in_joingroup_locked failed",
2209                            __func__);
2210			goto out_inp_locked;
2211		}
2212		/*
2213		 * NOTE: Refcount from in_joingroup_locked()
2214		 * is protecting membership.
2215		 */
2216		ip_mfilter_insert(&imo->imo_head, imf);
2217	} else {
2218		CTR1(KTR_IGMPV3, "%s: merge inm state", __func__);
2219		IN_MULTI_LIST_LOCK();
2220		error = inm_merge(inm, imf);
2221		if (error) {
2222			CTR1(KTR_IGMPV3, "%s: failed to merge inm state",
2223				 __func__);
2224			IN_MULTI_LIST_UNLOCK();
2225			imf_rollback(imf);
2226			imf_reap(imf);
2227			goto out_inp_locked;
2228		}
2229		CTR1(KTR_IGMPV3, "%s: doing igmp downcall", __func__);
2230		error = igmp_change_state(inm);
2231		IN_MULTI_LIST_UNLOCK();
2232		if (error) {
2233			CTR1(KTR_IGMPV3, "%s: failed igmp downcall",
2234			    __func__);
2235			imf_rollback(imf);
2236			imf_reap(imf);
2237			goto out_inp_locked;
2238		}
2239	}
2240
2241	imf_commit(imf);
2242	imf = NULL;
2243
2244out_inp_locked:
2245	INP_WUNLOCK(inp);
2246out_inp_unlocked:
2247	IN_MULTI_UNLOCK();
2248
2249	if (is_new && imf) {
2250		if (imf->imf_inm != NULL) {
2251			IN_MULTI_LIST_LOCK();
2252			inm_release_deferred(imf->imf_inm);
2253			IN_MULTI_LIST_UNLOCK();
2254		}
2255		ip_mfilter_free(imf);
2256	}
2257	return (error);
2258}
2259
2260/*
2261 * Leave an IPv4 multicast group on an inpcb, possibly with a source.
2262 */
2263static int
2264inp_leave_group(struct inpcb *inp, struct sockopt *sopt)
2265{
2266	struct group_source_req		 gsr;
2267	struct ip_mreq_source		 mreqs;
2268	struct rm_priotracker		 in_ifa_tracker;
2269	sockunion_t			*gsa, *ssa;
2270	struct ifnet			*ifp;
2271	struct in_mfilter		*imf;
2272	struct ip_moptions		*imo;
2273	struct in_msource		*ims;
2274	struct in_multi			*inm;
2275	int				 error;
2276	bool				 is_final;
2277
2278	ifp = NULL;
2279	error = 0;
2280	is_final = true;
2281
2282	memset(&gsr, 0, sizeof(struct group_source_req));
2283	gsa = (sockunion_t *)&gsr.gsr_group;
2284	gsa->ss.ss_family = AF_UNSPEC;
2285	ssa = (sockunion_t *)&gsr.gsr_source;
2286	ssa->ss.ss_family = AF_UNSPEC;
2287
2288	switch (sopt->sopt_name) {
2289	case IP_DROP_MEMBERSHIP:
2290	case IP_DROP_SOURCE_MEMBERSHIP:
2291		if (sopt->sopt_name == IP_DROP_MEMBERSHIP) {
2292			error = sooptcopyin(sopt, &mreqs,
2293			    sizeof(struct ip_mreq),
2294			    sizeof(struct ip_mreq));
2295			/*
2296			 * Swap interface and sourceaddr arguments,
2297			 * as ip_mreq and ip_mreq_source are laid
2298			 * out differently.
2299			 */
2300			mreqs.imr_interface = mreqs.imr_sourceaddr;
2301			mreqs.imr_sourceaddr.s_addr = INADDR_ANY;
2302		} else if (sopt->sopt_name == IP_DROP_SOURCE_MEMBERSHIP) {
2303			error = sooptcopyin(sopt, &mreqs,
2304			    sizeof(struct ip_mreq_source),
2305			    sizeof(struct ip_mreq_source));
2306		}
2307		if (error)
2308			return (error);
2309
2310		gsa->sin.sin_family = AF_INET;
2311		gsa->sin.sin_len = sizeof(struct sockaddr_in);
2312		gsa->sin.sin_addr = mreqs.imr_multiaddr;
2313
2314		if (sopt->sopt_name == IP_DROP_SOURCE_MEMBERSHIP) {
2315			ssa->sin.sin_family = AF_INET;
2316			ssa->sin.sin_len = sizeof(struct sockaddr_in);
2317			ssa->sin.sin_addr = mreqs.imr_sourceaddr;
2318		}
2319
2320		/*
2321		 * Attempt to look up hinted ifp from interface address.
2322		 * Fallthrough with null ifp iff lookup fails, to
2323		 * preserve 4.4BSD mcast API idempotence.
2324		 * XXX NOTE WELL: The RFC 3678 API is preferred because
2325		 * using an IPv4 address as a key is racy.
2326		 */
2327		if (!in_nullhost(mreqs.imr_interface)) {
2328			IN_IFADDR_RLOCK(&in_ifa_tracker);
2329			INADDR_TO_IFP(mreqs.imr_interface, ifp);
2330			IN_IFADDR_RUNLOCK(&in_ifa_tracker);
2331		}
2332		CTR3(KTR_IGMPV3, "%s: imr_interface = 0x%08x, ifp = %p",
2333		    __func__, ntohl(mreqs.imr_interface.s_addr), ifp);
2334
2335		break;
2336
2337	case MCAST_LEAVE_GROUP:
2338	case MCAST_LEAVE_SOURCE_GROUP:
2339		if (sopt->sopt_name == MCAST_LEAVE_GROUP) {
2340			error = sooptcopyin(sopt, &gsr,
2341			    sizeof(struct group_req),
2342			    sizeof(struct group_req));
2343		} else if (sopt->sopt_name == MCAST_LEAVE_SOURCE_GROUP) {
2344			error = sooptcopyin(sopt, &gsr,
2345			    sizeof(struct group_source_req),
2346			    sizeof(struct group_source_req));
2347		}
2348		if (error)
2349			return (error);
2350
2351		if (gsa->sin.sin_family != AF_INET ||
2352		    gsa->sin.sin_len != sizeof(struct sockaddr_in))
2353			return (EINVAL);
2354
2355		if (sopt->sopt_name == MCAST_LEAVE_SOURCE_GROUP) {
2356			if (ssa->sin.sin_family != AF_INET ||
2357			    ssa->sin.sin_len != sizeof(struct sockaddr_in))
2358				return (EINVAL);
2359		}
2360
2361		if (gsr.gsr_interface == 0 || V_if_index < gsr.gsr_interface)
2362			return (EADDRNOTAVAIL);
2363
2364		ifp = ifnet_byindex(gsr.gsr_interface);
2365
2366		if (ifp == NULL)
2367			return (EADDRNOTAVAIL);
2368		break;
2369
2370	default:
2371		CTR2(KTR_IGMPV3, "%s: unknown sopt_name %d",
2372		    __func__, sopt->sopt_name);
2373		return (EOPNOTSUPP);
2374		break;
2375	}
2376
2377	if (!IN_MULTICAST(ntohl(gsa->sin.sin_addr.s_addr)))
2378		return (EINVAL);
2379
2380	IN_MULTI_LOCK();
2381
2382	/*
2383	 * Find the membership in the membership list.
2384	 */
2385	imo = inp_findmoptions(inp);
2386	imf = imo_match_group(imo, ifp, &gsa->sa);
2387	if (imf == NULL) {
2388		error = EADDRNOTAVAIL;
2389		goto out_inp_locked;
2390	}
2391	inm = imf->imf_inm;
2392
2393	if (ssa->ss.ss_family != AF_UNSPEC)
2394		is_final = false;
2395
2396	/*
2397	 * Begin state merge transaction at socket layer.
2398	 */
2399	INP_WLOCK_ASSERT(inp);
2400
2401	/*
2402	 * If we were instructed only to leave a given source, do so.
2403	 * MCAST_LEAVE_SOURCE_GROUP is only valid for inclusive memberships.
2404	 */
2405	if (is_final) {
2406		ip_mfilter_remove(&imo->imo_head, imf);
2407		imf_leave(imf);
2408
2409		/*
2410		 * Give up the multicast address record to which
2411		 * the membership points.
2412		 */
2413		(void) in_leavegroup_locked(imf->imf_inm, imf);
2414	} else {
2415		if (imf->imf_st[0] == MCAST_EXCLUDE) {
2416			error = EADDRNOTAVAIL;
2417			goto out_inp_locked;
2418		}
2419		ims = imo_match_source(imf, &ssa->sa);
2420		if (ims == NULL) {
2421			CTR3(KTR_IGMPV3, "%s: source 0x%08x %spresent",
2422			    __func__, ntohl(ssa->sin.sin_addr.s_addr), "not ");
2423			error = EADDRNOTAVAIL;
2424			goto out_inp_locked;
2425		}
2426		CTR2(KTR_IGMPV3, "%s: %s source", __func__, "block");
2427		error = imf_prune(imf, &ssa->sin);
2428		if (error) {
2429			CTR1(KTR_IGMPV3, "%s: merge imf state failed",
2430			    __func__);
2431			goto out_inp_locked;
2432		}
2433	}
2434
2435	/*
2436	 * Begin state merge transaction at IGMP layer.
2437	 */
2438	if (!is_final) {
2439		CTR1(KTR_IGMPV3, "%s: merge inm state", __func__);
2440		IN_MULTI_LIST_LOCK();
2441		error = inm_merge(inm, imf);
2442		if (error) {
2443			CTR1(KTR_IGMPV3, "%s: failed to merge inm state",
2444			    __func__);
2445			IN_MULTI_LIST_UNLOCK();
2446			imf_rollback(imf);
2447			imf_reap(imf);
2448			goto out_inp_locked;
2449		}
2450
2451		CTR1(KTR_IGMPV3, "%s: doing igmp downcall", __func__);
2452		error = igmp_change_state(inm);
2453		IN_MULTI_LIST_UNLOCK();
2454		if (error) {
2455			CTR1(KTR_IGMPV3, "%s: failed igmp downcall",
2456			    __func__);
2457			imf_rollback(imf);
2458			imf_reap(imf);
2459			goto out_inp_locked;
2460		}
2461	}
2462	imf_commit(imf);
2463	imf_reap(imf);
2464
2465out_inp_locked:
2466	INP_WUNLOCK(inp);
2467
2468	if (is_final && imf)
2469		ip_mfilter_free(imf);
2470
2471	IN_MULTI_UNLOCK();
2472	return (error);
2473}
2474
2475/*
2476 * Select the interface for transmitting IPv4 multicast datagrams.
2477 *
2478 * Either an instance of struct in_addr or an instance of struct ip_mreqn
2479 * may be passed to this socket option. An address of INADDR_ANY or an
2480 * interface index of 0 is used to remove a previous selection.
2481 * When no interface is selected, one is chosen for every send.
2482 */
2483static int
2484inp_set_multicast_if(struct inpcb *inp, struct sockopt *sopt)
2485{
2486	struct rm_priotracker	 in_ifa_tracker;
2487	struct in_addr		 addr;
2488	struct ip_mreqn		 mreqn;
2489	struct ifnet		*ifp;
2490	struct ip_moptions	*imo;
2491	int			 error;
2492
2493	if (sopt->sopt_valsize == sizeof(struct ip_mreqn)) {
2494		/*
2495		 * An interface index was specified using the
2496		 * Linux-derived ip_mreqn structure.
2497		 */
2498		error = sooptcopyin(sopt, &mreqn, sizeof(struct ip_mreqn),
2499		    sizeof(struct ip_mreqn));
2500		if (error)
2501			return (error);
2502
2503		if (mreqn.imr_ifindex < 0 || V_if_index < mreqn.imr_ifindex)
2504			return (EINVAL);
2505
2506		if (mreqn.imr_ifindex == 0) {
2507			ifp = NULL;
2508		} else {
2509			ifp = ifnet_byindex(mreqn.imr_ifindex);
2510			if (ifp == NULL)
2511				return (EADDRNOTAVAIL);
2512		}
2513	} else {
2514		/*
2515		 * An interface was specified by IPv4 address.
2516		 * This is the traditional BSD usage.
2517		 */
2518		error = sooptcopyin(sopt, &addr, sizeof(struct in_addr),
2519		    sizeof(struct in_addr));
2520		if (error)
2521			return (error);
2522		if (in_nullhost(addr)) {
2523			ifp = NULL;
2524		} else {
2525			IN_IFADDR_RLOCK(&in_ifa_tracker);
2526			INADDR_TO_IFP(addr, ifp);
2527			IN_IFADDR_RUNLOCK(&in_ifa_tracker);
2528			if (ifp == NULL)
2529				return (EADDRNOTAVAIL);
2530		}
2531		CTR3(KTR_IGMPV3, "%s: ifp = %p, addr = 0x%08x", __func__, ifp,
2532		    ntohl(addr.s_addr));
2533	}
2534
2535	/* Reject interfaces which do not support multicast. */
2536	if (ifp != NULL && (ifp->if_flags & IFF_MULTICAST) == 0)
2537		return (EOPNOTSUPP);
2538
2539	imo = inp_findmoptions(inp);
2540	imo->imo_multicast_ifp = ifp;
2541	imo->imo_multicast_addr.s_addr = INADDR_ANY;
2542	INP_WUNLOCK(inp);
2543
2544	return (0);
2545}
2546
2547/*
2548 * Atomically set source filters on a socket for an IPv4 multicast group.
2549 *
2550 * SMPng: NOTE: Potentially calls malloc(M_WAITOK) with Giant held.
2551 */
2552static int
2553inp_set_source_filters(struct inpcb *inp, struct sockopt *sopt)
2554{
2555	struct __msfilterreq	 msfr;
2556	sockunion_t		*gsa;
2557	struct ifnet		*ifp;
2558	struct in_mfilter	*imf;
2559	struct ip_moptions	*imo;
2560	struct in_multi		*inm;
2561	int			 error;
2562
2563	error = sooptcopyin(sopt, &msfr, sizeof(struct __msfilterreq),
2564	    sizeof(struct __msfilterreq));
2565	if (error)
2566		return (error);
2567
2568	if (msfr.msfr_nsrcs > in_mcast_maxsocksrc)
2569		return (ENOBUFS);
2570
2571	if ((msfr.msfr_fmode != MCAST_EXCLUDE &&
2572	     msfr.msfr_fmode != MCAST_INCLUDE))
2573		return (EINVAL);
2574
2575	if (msfr.msfr_group.ss_family != AF_INET ||
2576	    msfr.msfr_group.ss_len != sizeof(struct sockaddr_in))
2577		return (EINVAL);
2578
2579	gsa = (sockunion_t *)&msfr.msfr_group;
2580	if (!IN_MULTICAST(ntohl(gsa->sin.sin_addr.s_addr)))
2581		return (EINVAL);
2582
2583	gsa->sin.sin_port = 0;	/* ignore port */
2584
2585	if (msfr.msfr_ifindex == 0 || V_if_index < msfr.msfr_ifindex)
2586		return (EADDRNOTAVAIL);
2587
2588	ifp = ifnet_byindex(msfr.msfr_ifindex);
2589	if (ifp == NULL)
2590		return (EADDRNOTAVAIL);
2591
2592	IN_MULTI_LOCK();
2593
2594	/*
2595	 * Take the INP write lock.
2596	 * Check if this socket is a member of this group.
2597	 */
2598	imo = inp_findmoptions(inp);
2599	imf = imo_match_group(imo, ifp, &gsa->sa);
2600	if (imf == NULL) {
2601		error = EADDRNOTAVAIL;
2602		goto out_inp_locked;
2603	}
2604	inm = imf->imf_inm;
2605
2606	/*
2607	 * Begin state merge transaction at socket layer.
2608	 */
2609	INP_WLOCK_ASSERT(inp);
2610
2611	imf->imf_st[1] = msfr.msfr_fmode;
2612
2613	/*
2614	 * Apply any new source filters, if present.
2615	 * Make a copy of the user-space source vector so
2616	 * that we may copy them with a single copyin. This
2617	 * allows us to deal with page faults up-front.
2618	 */
2619	if (msfr.msfr_nsrcs > 0) {
2620		struct in_msource	*lims;
2621		struct sockaddr_in	*psin;
2622		struct sockaddr_storage	*kss, *pkss;
2623		int			 i;
2624
2625		INP_WUNLOCK(inp);
2626
2627		CTR2(KTR_IGMPV3, "%s: loading %lu source list entries",
2628		    __func__, (unsigned long)msfr.msfr_nsrcs);
2629		kss = malloc(sizeof(struct sockaddr_storage) * msfr.msfr_nsrcs,
2630		    M_TEMP, M_WAITOK);
2631		error = copyin(msfr.msfr_srcs, kss,
2632		    sizeof(struct sockaddr_storage) * msfr.msfr_nsrcs);
2633		if (error) {
2634			free(kss, M_TEMP);
2635			return (error);
2636		}
2637
2638		INP_WLOCK(inp);
2639
2640		/*
2641		 * Mark all source filters as UNDEFINED at t1.
2642		 * Restore new group filter mode, as imf_leave()
2643		 * will set it to INCLUDE.
2644		 */
2645		imf_leave(imf);
2646		imf->imf_st[1] = msfr.msfr_fmode;
2647
2648		/*
2649		 * Update socket layer filters at t1, lazy-allocating
2650		 * new entries. This saves a bunch of memory at the
2651		 * cost of one RB_FIND() per source entry; duplicate
2652		 * entries in the msfr_nsrcs vector are ignored.
2653		 * If we encounter an error, rollback transaction.
2654		 *
2655		 * XXX This too could be replaced with a set-symmetric
2656		 * difference like loop to avoid walking from root
2657		 * every time, as the key space is common.
2658		 */
2659		for (i = 0, pkss = kss; i < msfr.msfr_nsrcs; i++, pkss++) {
2660			psin = (struct sockaddr_in *)pkss;
2661			if (psin->sin_family != AF_INET) {
2662				error = EAFNOSUPPORT;
2663				break;
2664			}
2665			if (psin->sin_len != sizeof(struct sockaddr_in)) {
2666				error = EINVAL;
2667				break;
2668			}
2669			error = imf_get_source(imf, psin, &lims);
2670			if (error)
2671				break;
2672			lims->imsl_st[1] = imf->imf_st[1];
2673		}
2674		free(kss, M_TEMP);
2675	}
2676
2677	if (error)
2678		goto out_imf_rollback;
2679
2680	INP_WLOCK_ASSERT(inp);
2681
2682	/*
2683	 * Begin state merge transaction at IGMP layer.
2684	 */
2685	CTR1(KTR_IGMPV3, "%s: merge inm state", __func__);
2686	IN_MULTI_LIST_LOCK();
2687	error = inm_merge(inm, imf);
2688	if (error) {
2689		CTR1(KTR_IGMPV3, "%s: failed to merge inm state", __func__);
2690		IN_MULTI_LIST_UNLOCK();
2691		goto out_imf_rollback;
2692	}
2693
2694	CTR1(KTR_IGMPV3, "%s: doing igmp downcall", __func__);
2695	error = igmp_change_state(inm);
2696	IN_MULTI_LIST_UNLOCK();
2697	if (error)
2698		CTR1(KTR_IGMPV3, "%s: failed igmp downcall", __func__);
2699
2700out_imf_rollback:
2701	if (error)
2702		imf_rollback(imf);
2703	else
2704		imf_commit(imf);
2705
2706	imf_reap(imf);
2707
2708out_inp_locked:
2709	INP_WUNLOCK(inp);
2710	IN_MULTI_UNLOCK();
2711	return (error);
2712}
2713
2714/*
2715 * Set the IP multicast options in response to user setsockopt().
2716 *
2717 * Many of the socket options handled in this function duplicate the
2718 * functionality of socket options in the regular unicast API. However,
2719 * it is not possible to merge the duplicate code, because the idempotence
2720 * of the IPv4 multicast part of the BSD Sockets API must be preserved;
2721 * the effects of these options must be treated as separate and distinct.
2722 *
2723 * SMPng: XXX: Unlocked read of inp_socket believed OK.
2724 * FUTURE: The IP_MULTICAST_VIF option may be eliminated if MROUTING
2725 * is refactored to no longer use vifs.
2726 */
2727int
2728inp_setmoptions(struct inpcb *inp, struct sockopt *sopt)
2729{
2730	struct ip_moptions	*imo;
2731	int			 error;
2732
2733	error = 0;
2734
2735	/*
2736	 * If socket is neither of type SOCK_RAW or SOCK_DGRAM,
2737	 * or is a divert socket, reject it.
2738	 */
2739	if (inp->inp_socket->so_proto->pr_protocol == IPPROTO_DIVERT ||
2740	    (inp->inp_socket->so_proto->pr_type != SOCK_RAW &&
2741	     inp->inp_socket->so_proto->pr_type != SOCK_DGRAM))
2742		return (EOPNOTSUPP);
2743
2744	switch (sopt->sopt_name) {
2745	case IP_MULTICAST_VIF: {
2746		int vifi;
2747		/*
2748		 * Select a multicast VIF for transmission.
2749		 * Only useful if multicast forwarding is active.
2750		 */
2751		if (legal_vif_num == NULL) {
2752			error = EOPNOTSUPP;
2753			break;
2754		}
2755		error = sooptcopyin(sopt, &vifi, sizeof(int), sizeof(int));
2756		if (error)
2757			break;
2758		if (!legal_vif_num(vifi) && (vifi != -1)) {
2759			error = EINVAL;
2760			break;
2761		}
2762		imo = inp_findmoptions(inp);
2763		imo->imo_multicast_vif = vifi;
2764		INP_WUNLOCK(inp);
2765		break;
2766	}
2767
2768	case IP_MULTICAST_IF:
2769		error = inp_set_multicast_if(inp, sopt);
2770		break;
2771
2772	case IP_MULTICAST_TTL: {
2773		u_char ttl;
2774
2775		/*
2776		 * Set the IP time-to-live for outgoing multicast packets.
2777		 * The original multicast API required a char argument,
2778		 * which is inconsistent with the rest of the socket API.
2779		 * We allow either a char or an int.
2780		 */
2781		if (sopt->sopt_valsize == sizeof(u_char)) {
2782			error = sooptcopyin(sopt, &ttl, sizeof(u_char),
2783			    sizeof(u_char));
2784			if (error)
2785				break;
2786		} else {
2787			u_int ittl;
2788
2789			error = sooptcopyin(sopt, &ittl, sizeof(u_int),
2790			    sizeof(u_int));
2791			if (error)
2792				break;
2793			if (ittl > 255) {
2794				error = EINVAL;
2795				break;
2796			}
2797			ttl = (u_char)ittl;
2798		}
2799		imo = inp_findmoptions(inp);
2800		imo->imo_multicast_ttl = ttl;
2801		INP_WUNLOCK(inp);
2802		break;
2803	}
2804
2805	case IP_MULTICAST_LOOP: {
2806		u_char loop;
2807
2808		/*
2809		 * Set the loopback flag for outgoing multicast packets.
2810		 * Must be zero or one.  The original multicast API required a
2811		 * char argument, which is inconsistent with the rest
2812		 * of the socket API.  We allow either a char or an int.
2813		 */
2814		if (sopt->sopt_valsize == sizeof(u_char)) {
2815			error = sooptcopyin(sopt, &loop, sizeof(u_char),
2816			    sizeof(u_char));
2817			if (error)
2818				break;
2819		} else {
2820			u_int iloop;
2821
2822			error = sooptcopyin(sopt, &iloop, sizeof(u_int),
2823					    sizeof(u_int));
2824			if (error)
2825				break;
2826			loop = (u_char)iloop;
2827		}
2828		imo = inp_findmoptions(inp);
2829		imo->imo_multicast_loop = !!loop;
2830		INP_WUNLOCK(inp);
2831		break;
2832	}
2833
2834	case IP_ADD_MEMBERSHIP:
2835	case IP_ADD_SOURCE_MEMBERSHIP:
2836	case MCAST_JOIN_GROUP:
2837	case MCAST_JOIN_SOURCE_GROUP:
2838		error = inp_join_group(inp, sopt);
2839		break;
2840
2841	case IP_DROP_MEMBERSHIP:
2842	case IP_DROP_SOURCE_MEMBERSHIP:
2843	case MCAST_LEAVE_GROUP:
2844	case MCAST_LEAVE_SOURCE_GROUP:
2845		error = inp_leave_group(inp, sopt);
2846		break;
2847
2848	case IP_BLOCK_SOURCE:
2849	case IP_UNBLOCK_SOURCE:
2850	case MCAST_BLOCK_SOURCE:
2851	case MCAST_UNBLOCK_SOURCE:
2852		error = inp_block_unblock_source(inp, sopt);
2853		break;
2854
2855	case IP_MSFILTER:
2856		error = inp_set_source_filters(inp, sopt);
2857		break;
2858
2859	default:
2860		error = EOPNOTSUPP;
2861		break;
2862	}
2863
2864	INP_UNLOCK_ASSERT(inp);
2865
2866	return (error);
2867}
2868
2869/*
2870 * Expose IGMP's multicast filter mode and source list(s) to userland,
2871 * keyed by (ifindex, group).
2872 * The filter mode is written out as a uint32_t, followed by
2873 * 0..n of struct in_addr.
2874 * For use by ifmcstat(8).
2875 * SMPng: NOTE: unlocked read of ifindex space.
2876 */
2877static int
2878sysctl_ip_mcast_filters(SYSCTL_HANDLER_ARGS)
2879{
2880	struct in_addr			 src, group;
2881	struct ifnet			*ifp;
2882	struct ifmultiaddr		*ifma;
2883	struct in_multi			*inm;
2884	struct ip_msource		*ims;
2885	int				*name;
2886	int				 retval;
2887	u_int				 namelen;
2888	uint32_t			 fmode, ifindex;
2889
2890	name = (int *)arg1;
2891	namelen = arg2;
2892
2893	if (req->newptr != NULL)
2894		return (EPERM);
2895
2896	if (namelen != 2)
2897		return (EINVAL);
2898
2899	ifindex = name[0];
2900	if (ifindex <= 0 || ifindex > V_if_index) {
2901		CTR2(KTR_IGMPV3, "%s: ifindex %u out of range",
2902		    __func__, ifindex);
2903		return (ENOENT);
2904	}
2905
2906	group.s_addr = name[1];
2907	if (!IN_MULTICAST(ntohl(group.s_addr))) {
2908		CTR2(KTR_IGMPV3, "%s: group 0x%08x is not multicast",
2909		    __func__, ntohl(group.s_addr));
2910		return (EINVAL);
2911	}
2912
2913	ifp = ifnet_byindex(ifindex);
2914	if (ifp == NULL) {
2915		CTR2(KTR_IGMPV3, "%s: no ifp for ifindex %u",
2916		    __func__, ifindex);
2917		return (ENOENT);
2918	}
2919
2920	retval = sysctl_wire_old_buffer(req,
2921	    sizeof(uint32_t) + (in_mcast_maxgrpsrc * sizeof(struct in_addr)));
2922	if (retval)
2923		return (retval);
2924
2925	IN_MULTI_LIST_LOCK();
2926
2927	IF_ADDR_RLOCK(ifp);
2928	CK_STAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
2929		if (ifma->ifma_addr->sa_family != AF_INET ||
2930		    ifma->ifma_protospec == NULL)
2931			continue;
2932		inm = (struct in_multi *)ifma->ifma_protospec;
2933		if (!in_hosteq(inm->inm_addr, group))
2934			continue;
2935		fmode = inm->inm_st[1].iss_fmode;
2936		retval = SYSCTL_OUT(req, &fmode, sizeof(uint32_t));
2937		if (retval != 0)
2938			break;
2939		RB_FOREACH(ims, ip_msource_tree, &inm->inm_srcs) {
2940			CTR2(KTR_IGMPV3, "%s: visit node 0x%08x", __func__,
2941			    ims->ims_haddr);
2942			/*
2943			 * Only copy-out sources which are in-mode.
2944			 */
2945			if (fmode != ims_get_mode(inm, ims, 1)) {
2946				CTR1(KTR_IGMPV3, "%s: skip non-in-mode",
2947				    __func__);
2948				continue;
2949			}
2950			src.s_addr = htonl(ims->ims_haddr);
2951			retval = SYSCTL_OUT(req, &src, sizeof(struct in_addr));
2952			if (retval != 0)
2953				break;
2954		}
2955	}
2956	IF_ADDR_RUNLOCK(ifp);
2957
2958	IN_MULTI_LIST_UNLOCK();
2959
2960	return (retval);
2961}
2962
2963#if defined(KTR) && (KTR_COMPILE & KTR_IGMPV3)
2964
2965static const char *inm_modestrs[] = {
2966	[MCAST_UNDEFINED] = "un",
2967	[MCAST_INCLUDE] = "in",
2968	[MCAST_EXCLUDE] = "ex",
2969};
2970_Static_assert(MCAST_UNDEFINED == 0 &&
2971	       MCAST_EXCLUDE + 1 == nitems(inm_modestrs),
2972	       "inm_modestrs: no longer matches #defines");
2973
2974static const char *
2975inm_mode_str(const int mode)
2976{
2977
2978	if (mode >= MCAST_UNDEFINED && mode <= MCAST_EXCLUDE)
2979		return (inm_modestrs[mode]);
2980	return ("??");
2981}
2982
2983static const char *inm_statestrs[] = {
2984	[IGMP_NOT_MEMBER] = "not-member",
2985	[IGMP_SILENT_MEMBER] = "silent",
2986	[IGMP_REPORTING_MEMBER] = "reporting",
2987	[IGMP_IDLE_MEMBER] = "idle",
2988	[IGMP_LAZY_MEMBER] = "lazy",
2989	[IGMP_SLEEPING_MEMBER] = "sleeping",
2990	[IGMP_AWAKENING_MEMBER] = "awakening",
2991	[IGMP_G_QUERY_PENDING_MEMBER] = "query-pending",
2992	[IGMP_SG_QUERY_PENDING_MEMBER] = "sg-query-pending",
2993	[IGMP_LEAVING_MEMBER] = "leaving",
2994};
2995_Static_assert(IGMP_NOT_MEMBER == 0 &&
2996	       IGMP_LEAVING_MEMBER + 1 == nitems(inm_statestrs),
2997	       "inm_statetrs: no longer matches #defines");
2998
2999static const char *
3000inm_state_str(const int state)
3001{
3002
3003	if (state >= IGMP_NOT_MEMBER && state <= IGMP_LEAVING_MEMBER)
3004		return (inm_statestrs[state]);
3005	return ("??");
3006}
3007
3008/*
3009 * Dump an in_multi structure to the console.
3010 */
3011void
3012inm_print(const struct in_multi *inm)
3013{
3014	int t;
3015	char addrbuf[INET_ADDRSTRLEN];
3016
3017	if ((ktr_mask & KTR_IGMPV3) == 0)
3018		return;
3019
3020	printf("%s: --- begin inm %p ---\n", __func__, inm);
3021	printf("addr %s ifp %p(%s) ifma %p\n",
3022	    inet_ntoa_r(inm->inm_addr, addrbuf),
3023	    inm->inm_ifp,
3024	    inm->inm_ifp->if_xname,
3025	    inm->inm_ifma);
3026	printf("timer %u state %s refcount %u scq.len %u\n",
3027	    inm->inm_timer,
3028	    inm_state_str(inm->inm_state),
3029	    inm->inm_refcount,
3030	    inm->inm_scq.mq_len);
3031	printf("igi %p nsrc %lu sctimer %u scrv %u\n",
3032	    inm->inm_igi,
3033	    inm->inm_nsrc,
3034	    inm->inm_sctimer,
3035	    inm->inm_scrv);
3036	for (t = 0; t < 2; t++) {
3037		printf("t%d: fmode %s asm %u ex %u in %u rec %u\n", t,
3038		    inm_mode_str(inm->inm_st[t].iss_fmode),
3039		    inm->inm_st[t].iss_asm,
3040		    inm->inm_st[t].iss_ex,
3041		    inm->inm_st[t].iss_in,
3042		    inm->inm_st[t].iss_rec);
3043	}
3044	printf("%s: --- end inm %p ---\n", __func__, inm);
3045}
3046
3047#else /* !KTR || !(KTR_COMPILE & KTR_IGMPV3) */
3048
3049void
3050inm_print(const struct in_multi *inm)
3051{
3052
3053}
3054
3055#endif /* KTR && (KTR_COMPILE & KTR_IGMPV3) */
3056
3057RB_GENERATE(ip_msource_tree, ip_msource, ims_link, ip_msource_cmp);
3058