xref: /openbmc/linux/net/ipv6/mcast.c (revision f20c7d91)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *	Multicast support for IPv6
4  *	Linux INET6 implementation
5  *
6  *	Authors:
7  *	Pedro Roque		<roque@di.fc.ul.pt>
8  *
9  *	Based on linux/ipv4/igmp.c and linux/ipv4/ip_sockglue.c
10  */
11 
12 /* Changes:
13  *
14  *	yoshfuji	: fix format of router-alert option
15  *	YOSHIFUJI Hideaki @USAGI:
16  *		Fixed source address for MLD message based on
17  *		<draft-ietf-magma-mld-source-05.txt>.
18  *	YOSHIFUJI Hideaki @USAGI:
19  *		- Ignore Queries for invalid addresses.
20  *		- MLD for link-local addresses.
21  *	David L Stevens <dlstevens@us.ibm.com>:
22  *		- MLDv2 support
23  */
24 
25 #include <linux/module.h>
26 #include <linux/errno.h>
27 #include <linux/types.h>
28 #include <linux/string.h>
29 #include <linux/socket.h>
30 #include <linux/sockios.h>
31 #include <linux/jiffies.h>
32 #include <linux/times.h>
33 #include <linux/net.h>
34 #include <linux/in.h>
35 #include <linux/in6.h>
36 #include <linux/netdevice.h>
37 #include <linux/if_arp.h>
38 #include <linux/route.h>
39 #include <linux/init.h>
40 #include <linux/proc_fs.h>
41 #include <linux/seq_file.h>
42 #include <linux/slab.h>
43 #include <linux/pkt_sched.h>
44 #include <net/mld.h>
45 
46 #include <linux/netfilter.h>
47 #include <linux/netfilter_ipv6.h>
48 
49 #include <net/net_namespace.h>
50 #include <net/sock.h>
51 #include <net/snmp.h>
52 
53 #include <net/ipv6.h>
54 #include <net/protocol.h>
55 #include <net/if_inet6.h>
56 #include <net/ndisc.h>
57 #include <net/addrconf.h>
58 #include <net/ip6_route.h>
59 #include <net/inet_common.h>
60 
61 #include <net/ip6_checksum.h>
62 
63 /* Ensure that we have struct in6_addr aligned on 32bit word. */
64 static int __mld2_query_bugs[] __attribute__((__unused__)) = {
65 	BUILD_BUG_ON_ZERO(offsetof(struct mld2_query, mld2q_srcs) % 4),
66 	BUILD_BUG_ON_ZERO(offsetof(struct mld2_report, mld2r_grec) % 4),
67 	BUILD_BUG_ON_ZERO(offsetof(struct mld2_grec, grec_mca) % 4)
68 };
69 
70 static struct in6_addr mld2_all_mcr = MLD2_ALL_MCR_INIT;
71 
72 static void igmp6_join_group(struct ifmcaddr6 *ma);
73 static void igmp6_leave_group(struct ifmcaddr6 *ma);
74 static void igmp6_timer_handler(struct timer_list *t);
75 
76 static void mld_gq_timer_expire(struct timer_list *t);
77 static void mld_ifc_timer_expire(struct timer_list *t);
78 static void mld_ifc_event(struct inet6_dev *idev);
79 static void mld_add_delrec(struct inet6_dev *idev, struct ifmcaddr6 *pmc);
80 static void mld_del_delrec(struct inet6_dev *idev, struct ifmcaddr6 *pmc);
81 static void mld_clear_delrec(struct inet6_dev *idev);
82 static bool mld_in_v1_mode(const struct inet6_dev *idev);
83 static int sf_setstate(struct ifmcaddr6 *pmc);
84 static void sf_markstate(struct ifmcaddr6 *pmc);
85 static void ip6_mc_clear_src(struct ifmcaddr6 *pmc);
86 static int ip6_mc_del_src(struct inet6_dev *idev, const struct in6_addr *pmca,
87 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
88 			  int delta);
89 static int ip6_mc_add_src(struct inet6_dev *idev, const struct in6_addr *pmca,
90 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
91 			  int delta);
92 static int ip6_mc_leave_src(struct sock *sk, struct ipv6_mc_socklist *iml,
93 			    struct inet6_dev *idev);
94 static int __ipv6_dev_mc_inc(struct net_device *dev,
95 			     const struct in6_addr *addr, unsigned int mode);
96 
97 #define MLD_QRV_DEFAULT		2
98 /* RFC3810, 9.2. Query Interval */
99 #define MLD_QI_DEFAULT		(125 * HZ)
100 /* RFC3810, 9.3. Query Response Interval */
101 #define MLD_QRI_DEFAULT		(10 * HZ)
102 
103 /* RFC3810, 8.1 Query Version Distinctions */
104 #define MLD_V1_QUERY_LEN	24
105 #define MLD_V2_QUERY_LEN_MIN	28
106 
107 #define IPV6_MLD_MAX_MSF	64
108 
109 int sysctl_mld_max_msf __read_mostly = IPV6_MLD_MAX_MSF;
110 int sysctl_mld_qrv __read_mostly = MLD_QRV_DEFAULT;
111 
112 /*
113  *	socket join on multicast group
114  */
115 
116 #define for_each_pmc_rcu(np, pmc)				\
117 	for (pmc = rcu_dereference(np->ipv6_mc_list);		\
118 	     pmc != NULL;					\
119 	     pmc = rcu_dereference(pmc->next))
120 
121 static int unsolicited_report_interval(struct inet6_dev *idev)
122 {
123 	int iv;
124 
125 	if (mld_in_v1_mode(idev))
126 		iv = idev->cnf.mldv1_unsolicited_report_interval;
127 	else
128 		iv = idev->cnf.mldv2_unsolicited_report_interval;
129 
130 	return iv > 0 ? iv : 1;
131 }
132 
133 static int __ipv6_sock_mc_join(struct sock *sk, int ifindex,
134 			       const struct in6_addr *addr, unsigned int mode)
135 {
136 	struct net_device *dev = NULL;
137 	struct ipv6_mc_socklist *mc_lst;
138 	struct ipv6_pinfo *np = inet6_sk(sk);
139 	struct net *net = sock_net(sk);
140 	int err;
141 
142 	ASSERT_RTNL();
143 
144 	if (!ipv6_addr_is_multicast(addr))
145 		return -EINVAL;
146 
147 	rcu_read_lock();
148 	for_each_pmc_rcu(np, mc_lst) {
149 		if ((ifindex == 0 || mc_lst->ifindex == ifindex) &&
150 		    ipv6_addr_equal(&mc_lst->addr, addr)) {
151 			rcu_read_unlock();
152 			return -EADDRINUSE;
153 		}
154 	}
155 	rcu_read_unlock();
156 
157 	mc_lst = sock_kmalloc(sk, sizeof(struct ipv6_mc_socklist), GFP_KERNEL);
158 
159 	if (!mc_lst)
160 		return -ENOMEM;
161 
162 	mc_lst->next = NULL;
163 	mc_lst->addr = *addr;
164 
165 	if (ifindex == 0) {
166 		struct rt6_info *rt;
167 		rt = rt6_lookup(net, addr, NULL, 0, NULL, 0);
168 		if (rt) {
169 			dev = rt->dst.dev;
170 			ip6_rt_put(rt);
171 		}
172 	} else
173 		dev = __dev_get_by_index(net, ifindex);
174 
175 	if (!dev) {
176 		sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));
177 		return -ENODEV;
178 	}
179 
180 	mc_lst->ifindex = dev->ifindex;
181 	mc_lst->sfmode = mode;
182 	rwlock_init(&mc_lst->sflock);
183 	mc_lst->sflist = NULL;
184 
185 	/*
186 	 *	now add/increase the group membership on the device
187 	 */
188 
189 	err = __ipv6_dev_mc_inc(dev, addr, mode);
190 
191 	if (err) {
192 		sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));
193 		return err;
194 	}
195 
196 	mc_lst->next = np->ipv6_mc_list;
197 	rcu_assign_pointer(np->ipv6_mc_list, mc_lst);
198 
199 	return 0;
200 }
201 
202 int ipv6_sock_mc_join(struct sock *sk, int ifindex, const struct in6_addr *addr)
203 {
204 	return __ipv6_sock_mc_join(sk, ifindex, addr, MCAST_EXCLUDE);
205 }
206 EXPORT_SYMBOL(ipv6_sock_mc_join);
207 
208 int ipv6_sock_mc_join_ssm(struct sock *sk, int ifindex,
209 			  const struct in6_addr *addr, unsigned int mode)
210 {
211 	return __ipv6_sock_mc_join(sk, ifindex, addr, mode);
212 }
213 
214 /*
215  *	socket leave on multicast group
216  */
217 int ipv6_sock_mc_drop(struct sock *sk, int ifindex, const struct in6_addr *addr)
218 {
219 	struct ipv6_pinfo *np = inet6_sk(sk);
220 	struct ipv6_mc_socklist *mc_lst;
221 	struct ipv6_mc_socklist __rcu **lnk;
222 	struct net *net = sock_net(sk);
223 
224 	ASSERT_RTNL();
225 
226 	if (!ipv6_addr_is_multicast(addr))
227 		return -EINVAL;
228 
229 	for (lnk = &np->ipv6_mc_list;
230 	     (mc_lst = rtnl_dereference(*lnk)) != NULL;
231 	      lnk = &mc_lst->next) {
232 		if ((ifindex == 0 || mc_lst->ifindex == ifindex) &&
233 		    ipv6_addr_equal(&mc_lst->addr, addr)) {
234 			struct net_device *dev;
235 
236 			*lnk = mc_lst->next;
237 
238 			dev = __dev_get_by_index(net, mc_lst->ifindex);
239 			if (dev) {
240 				struct inet6_dev *idev = __in6_dev_get(dev);
241 
242 				(void) ip6_mc_leave_src(sk, mc_lst, idev);
243 				if (idev)
244 					__ipv6_dev_mc_dec(idev, &mc_lst->addr);
245 			} else
246 				(void) ip6_mc_leave_src(sk, mc_lst, NULL);
247 
248 			atomic_sub(sizeof(*mc_lst), &sk->sk_omem_alloc);
249 			kfree_rcu(mc_lst, rcu);
250 			return 0;
251 		}
252 	}
253 
254 	return -EADDRNOTAVAIL;
255 }
256 EXPORT_SYMBOL(ipv6_sock_mc_drop);
257 
258 /* called with rcu_read_lock() */
259 static struct inet6_dev *ip6_mc_find_dev_rcu(struct net *net,
260 					     const struct in6_addr *group,
261 					     int ifindex)
262 {
263 	struct net_device *dev = NULL;
264 	struct inet6_dev *idev = NULL;
265 
266 	if (ifindex == 0) {
267 		struct rt6_info *rt = rt6_lookup(net, group, NULL, 0, NULL, 0);
268 
269 		if (rt) {
270 			dev = rt->dst.dev;
271 			ip6_rt_put(rt);
272 		}
273 	} else
274 		dev = dev_get_by_index_rcu(net, ifindex);
275 
276 	if (!dev)
277 		return NULL;
278 	idev = __in6_dev_get(dev);
279 	if (!idev)
280 		return NULL;
281 	read_lock_bh(&idev->lock);
282 	if (idev->dead) {
283 		read_unlock_bh(&idev->lock);
284 		return NULL;
285 	}
286 	return idev;
287 }
288 
289 void __ipv6_sock_mc_close(struct sock *sk)
290 {
291 	struct ipv6_pinfo *np = inet6_sk(sk);
292 	struct ipv6_mc_socklist *mc_lst;
293 	struct net *net = sock_net(sk);
294 
295 	ASSERT_RTNL();
296 
297 	while ((mc_lst = rtnl_dereference(np->ipv6_mc_list)) != NULL) {
298 		struct net_device *dev;
299 
300 		np->ipv6_mc_list = mc_lst->next;
301 
302 		dev = __dev_get_by_index(net, mc_lst->ifindex);
303 		if (dev) {
304 			struct inet6_dev *idev = __in6_dev_get(dev);
305 
306 			(void) ip6_mc_leave_src(sk, mc_lst, idev);
307 			if (idev)
308 				__ipv6_dev_mc_dec(idev, &mc_lst->addr);
309 		} else
310 			(void) ip6_mc_leave_src(sk, mc_lst, NULL);
311 
312 		atomic_sub(sizeof(*mc_lst), &sk->sk_omem_alloc);
313 		kfree_rcu(mc_lst, rcu);
314 	}
315 }
316 
317 void ipv6_sock_mc_close(struct sock *sk)
318 {
319 	struct ipv6_pinfo *np = inet6_sk(sk);
320 
321 	if (!rcu_access_pointer(np->ipv6_mc_list))
322 		return;
323 	rtnl_lock();
324 	__ipv6_sock_mc_close(sk);
325 	rtnl_unlock();
326 }
327 
328 int ip6_mc_source(int add, int omode, struct sock *sk,
329 	struct group_source_req *pgsr)
330 {
331 	struct in6_addr *source, *group;
332 	struct ipv6_mc_socklist *pmc;
333 	struct inet6_dev *idev;
334 	struct ipv6_pinfo *inet6 = inet6_sk(sk);
335 	struct ip6_sf_socklist *psl;
336 	struct net *net = sock_net(sk);
337 	int i, j, rv;
338 	int leavegroup = 0;
339 	int pmclocked = 0;
340 	int err;
341 
342 	source = &((struct sockaddr_in6 *)&pgsr->gsr_source)->sin6_addr;
343 	group = &((struct sockaddr_in6 *)&pgsr->gsr_group)->sin6_addr;
344 
345 	if (!ipv6_addr_is_multicast(group))
346 		return -EINVAL;
347 
348 	rcu_read_lock();
349 	idev = ip6_mc_find_dev_rcu(net, group, pgsr->gsr_interface);
350 	if (!idev) {
351 		rcu_read_unlock();
352 		return -ENODEV;
353 	}
354 
355 	err = -EADDRNOTAVAIL;
356 
357 	for_each_pmc_rcu(inet6, pmc) {
358 		if (pgsr->gsr_interface && pmc->ifindex != pgsr->gsr_interface)
359 			continue;
360 		if (ipv6_addr_equal(&pmc->addr, group))
361 			break;
362 	}
363 	if (!pmc) {		/* must have a prior join */
364 		err = -EINVAL;
365 		goto done;
366 	}
367 	/* if a source filter was set, must be the same mode as before */
368 	if (pmc->sflist) {
369 		if (pmc->sfmode != omode) {
370 			err = -EINVAL;
371 			goto done;
372 		}
373 	} else if (pmc->sfmode != omode) {
374 		/* allow mode switches for empty-set filters */
375 		ip6_mc_add_src(idev, group, omode, 0, NULL, 0);
376 		ip6_mc_del_src(idev, group, pmc->sfmode, 0, NULL, 0);
377 		pmc->sfmode = omode;
378 	}
379 
380 	write_lock(&pmc->sflock);
381 	pmclocked = 1;
382 
383 	psl = pmc->sflist;
384 	if (!add) {
385 		if (!psl)
386 			goto done;	/* err = -EADDRNOTAVAIL */
387 		rv = !0;
388 		for (i = 0; i < psl->sl_count; i++) {
389 			rv = !ipv6_addr_equal(&psl->sl_addr[i], source);
390 			if (rv == 0)
391 				break;
392 		}
393 		if (rv)		/* source not found */
394 			goto done;	/* err = -EADDRNOTAVAIL */
395 
396 		/* special case - (INCLUDE, empty) == LEAVE_GROUP */
397 		if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
398 			leavegroup = 1;
399 			goto done;
400 		}
401 
402 		/* update the interface filter */
403 		ip6_mc_del_src(idev, group, omode, 1, source, 1);
404 
405 		for (j = i+1; j < psl->sl_count; j++)
406 			psl->sl_addr[j-1] = psl->sl_addr[j];
407 		psl->sl_count--;
408 		err = 0;
409 		goto done;
410 	}
411 	/* else, add a new source to the filter */
412 
413 	if (psl && psl->sl_count >= sysctl_mld_max_msf) {
414 		err = -ENOBUFS;
415 		goto done;
416 	}
417 	if (!psl || psl->sl_count == psl->sl_max) {
418 		struct ip6_sf_socklist *newpsl;
419 		int count = IP6_SFBLOCK;
420 
421 		if (psl)
422 			count += psl->sl_max;
423 		newpsl = sock_kmalloc(sk, IP6_SFLSIZE(count), GFP_ATOMIC);
424 		if (!newpsl) {
425 			err = -ENOBUFS;
426 			goto done;
427 		}
428 		newpsl->sl_max = count;
429 		newpsl->sl_count = count - IP6_SFBLOCK;
430 		if (psl) {
431 			for (i = 0; i < psl->sl_count; i++)
432 				newpsl->sl_addr[i] = psl->sl_addr[i];
433 			sock_kfree_s(sk, psl, IP6_SFLSIZE(psl->sl_max));
434 		}
435 		pmc->sflist = psl = newpsl;
436 	}
437 	rv = 1;	/* > 0 for insert logic below if sl_count is 0 */
438 	for (i = 0; i < psl->sl_count; i++) {
439 		rv = !ipv6_addr_equal(&psl->sl_addr[i], source);
440 		if (rv == 0) /* There is an error in the address. */
441 			goto done;
442 	}
443 	for (j = psl->sl_count-1; j >= i; j--)
444 		psl->sl_addr[j+1] = psl->sl_addr[j];
445 	psl->sl_addr[i] = *source;
446 	psl->sl_count++;
447 	err = 0;
448 	/* update the interface list */
449 	ip6_mc_add_src(idev, group, omode, 1, source, 1);
450 done:
451 	if (pmclocked)
452 		write_unlock(&pmc->sflock);
453 	read_unlock_bh(&idev->lock);
454 	rcu_read_unlock();
455 	if (leavegroup)
456 		err = ipv6_sock_mc_drop(sk, pgsr->gsr_interface, group);
457 	return err;
458 }
459 
460 int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf,
461 		    struct sockaddr_storage *list)
462 {
463 	const struct in6_addr *group;
464 	struct ipv6_mc_socklist *pmc;
465 	struct inet6_dev *idev;
466 	struct ipv6_pinfo *inet6 = inet6_sk(sk);
467 	struct ip6_sf_socklist *newpsl, *psl;
468 	struct net *net = sock_net(sk);
469 	int leavegroup = 0;
470 	int i, err;
471 
472 	group = &((struct sockaddr_in6 *)&gsf->gf_group)->sin6_addr;
473 
474 	if (!ipv6_addr_is_multicast(group))
475 		return -EINVAL;
476 	if (gsf->gf_fmode != MCAST_INCLUDE &&
477 	    gsf->gf_fmode != MCAST_EXCLUDE)
478 		return -EINVAL;
479 
480 	rcu_read_lock();
481 	idev = ip6_mc_find_dev_rcu(net, group, gsf->gf_interface);
482 
483 	if (!idev) {
484 		rcu_read_unlock();
485 		return -ENODEV;
486 	}
487 
488 	err = 0;
489 
490 	if (gsf->gf_fmode == MCAST_INCLUDE && gsf->gf_numsrc == 0) {
491 		leavegroup = 1;
492 		goto done;
493 	}
494 
495 	for_each_pmc_rcu(inet6, pmc) {
496 		if (pmc->ifindex != gsf->gf_interface)
497 			continue;
498 		if (ipv6_addr_equal(&pmc->addr, group))
499 			break;
500 	}
501 	if (!pmc) {		/* must have a prior join */
502 		err = -EINVAL;
503 		goto done;
504 	}
505 	if (gsf->gf_numsrc) {
506 		newpsl = sock_kmalloc(sk, IP6_SFLSIZE(gsf->gf_numsrc),
507 							  GFP_ATOMIC);
508 		if (!newpsl) {
509 			err = -ENOBUFS;
510 			goto done;
511 		}
512 		newpsl->sl_max = newpsl->sl_count = gsf->gf_numsrc;
513 		for (i = 0; i < newpsl->sl_count; ++i, ++list) {
514 			struct sockaddr_in6 *psin6;
515 
516 			psin6 = (struct sockaddr_in6 *)list;
517 			newpsl->sl_addr[i] = psin6->sin6_addr;
518 		}
519 		err = ip6_mc_add_src(idev, group, gsf->gf_fmode,
520 			newpsl->sl_count, newpsl->sl_addr, 0);
521 		if (err) {
522 			sock_kfree_s(sk, newpsl, IP6_SFLSIZE(newpsl->sl_max));
523 			goto done;
524 		}
525 	} else {
526 		newpsl = NULL;
527 		(void) ip6_mc_add_src(idev, group, gsf->gf_fmode, 0, NULL, 0);
528 	}
529 
530 	write_lock(&pmc->sflock);
531 	psl = pmc->sflist;
532 	if (psl) {
533 		(void) ip6_mc_del_src(idev, group, pmc->sfmode,
534 			psl->sl_count, psl->sl_addr, 0);
535 		sock_kfree_s(sk, psl, IP6_SFLSIZE(psl->sl_max));
536 	} else
537 		(void) ip6_mc_del_src(idev, group, pmc->sfmode, 0, NULL, 0);
538 	pmc->sflist = newpsl;
539 	pmc->sfmode = gsf->gf_fmode;
540 	write_unlock(&pmc->sflock);
541 	err = 0;
542 done:
543 	read_unlock_bh(&idev->lock);
544 	rcu_read_unlock();
545 	if (leavegroup)
546 		err = ipv6_sock_mc_drop(sk, gsf->gf_interface, group);
547 	return err;
548 }
549 
550 int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
551 	struct sockaddr_storage *p)
552 {
553 	int err, i, count, copycount;
554 	const struct in6_addr *group;
555 	struct ipv6_mc_socklist *pmc;
556 	struct inet6_dev *idev;
557 	struct ipv6_pinfo *inet6 = inet6_sk(sk);
558 	struct ip6_sf_socklist *psl;
559 	struct net *net = sock_net(sk);
560 
561 	group = &((struct sockaddr_in6 *)&gsf->gf_group)->sin6_addr;
562 
563 	if (!ipv6_addr_is_multicast(group))
564 		return -EINVAL;
565 
566 	rcu_read_lock();
567 	idev = ip6_mc_find_dev_rcu(net, group, gsf->gf_interface);
568 
569 	if (!idev) {
570 		rcu_read_unlock();
571 		return -ENODEV;
572 	}
573 
574 	err = -EADDRNOTAVAIL;
575 	/* changes to the ipv6_mc_list require the socket lock and
576 	 * rtnl lock. We have the socket lock and rcu read lock,
577 	 * so reading the list is safe.
578 	 */
579 
580 	for_each_pmc_rcu(inet6, pmc) {
581 		if (pmc->ifindex != gsf->gf_interface)
582 			continue;
583 		if (ipv6_addr_equal(group, &pmc->addr))
584 			break;
585 	}
586 	if (!pmc)		/* must have a prior join */
587 		goto done;
588 	gsf->gf_fmode = pmc->sfmode;
589 	psl = pmc->sflist;
590 	count = psl ? psl->sl_count : 0;
591 	read_unlock_bh(&idev->lock);
592 	rcu_read_unlock();
593 
594 	copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
595 	gsf->gf_numsrc = count;
596 	/* changes to psl require the socket lock, and a write lock
597 	 * on pmc->sflock. We have the socket lock so reading here is safe.
598 	 */
599 	for (i = 0; i < copycount; i++, p++) {
600 		struct sockaddr_in6 *psin6;
601 		struct sockaddr_storage ss;
602 
603 		psin6 = (struct sockaddr_in6 *)&ss;
604 		memset(&ss, 0, sizeof(ss));
605 		psin6->sin6_family = AF_INET6;
606 		psin6->sin6_addr = psl->sl_addr[i];
607 		if (copy_to_user(p, &ss, sizeof(ss)))
608 			return -EFAULT;
609 	}
610 	return 0;
611 done:
612 	read_unlock_bh(&idev->lock);
613 	rcu_read_unlock();
614 	return err;
615 }
616 
617 bool inet6_mc_check(struct sock *sk, const struct in6_addr *mc_addr,
618 		    const struct in6_addr *src_addr)
619 {
620 	struct ipv6_pinfo *np = inet6_sk(sk);
621 	struct ipv6_mc_socklist *mc;
622 	struct ip6_sf_socklist *psl;
623 	bool rv = true;
624 
625 	rcu_read_lock();
626 	for_each_pmc_rcu(np, mc) {
627 		if (ipv6_addr_equal(&mc->addr, mc_addr))
628 			break;
629 	}
630 	if (!mc) {
631 		rcu_read_unlock();
632 		return np->mc_all;
633 	}
634 	read_lock(&mc->sflock);
635 	psl = mc->sflist;
636 	if (!psl) {
637 		rv = mc->sfmode == MCAST_EXCLUDE;
638 	} else {
639 		int i;
640 
641 		for (i = 0; i < psl->sl_count; i++) {
642 			if (ipv6_addr_equal(&psl->sl_addr[i], src_addr))
643 				break;
644 		}
645 		if (mc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
646 			rv = false;
647 		if (mc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
648 			rv = false;
649 	}
650 	read_unlock(&mc->sflock);
651 	rcu_read_unlock();
652 
653 	return rv;
654 }
655 
656 static void igmp6_group_added(struct ifmcaddr6 *mc)
657 {
658 	struct net_device *dev = mc->idev->dev;
659 	char buf[MAX_ADDR_LEN];
660 
661 	if (IPV6_ADDR_MC_SCOPE(&mc->mca_addr) <
662 	    IPV6_ADDR_SCOPE_LINKLOCAL)
663 		return;
664 
665 	spin_lock_bh(&mc->mca_lock);
666 	if (!(mc->mca_flags&MAF_LOADED)) {
667 		mc->mca_flags |= MAF_LOADED;
668 		if (ndisc_mc_map(&mc->mca_addr, buf, dev, 0) == 0)
669 			dev_mc_add(dev, buf);
670 	}
671 	spin_unlock_bh(&mc->mca_lock);
672 
673 	if (!(dev->flags & IFF_UP) || (mc->mca_flags & MAF_NOREPORT))
674 		return;
675 
676 	if (mld_in_v1_mode(mc->idev)) {
677 		igmp6_join_group(mc);
678 		return;
679 	}
680 	/* else v2 */
681 
682 	/* Based on RFC3810 6.1, for newly added INCLUDE SSM, we
683 	 * should not send filter-mode change record as the mode
684 	 * should be from IN() to IN(A).
685 	 */
686 	if (mc->mca_sfmode == MCAST_EXCLUDE)
687 		mc->mca_crcount = mc->idev->mc_qrv;
688 
689 	mld_ifc_event(mc->idev);
690 }
691 
692 static void igmp6_group_dropped(struct ifmcaddr6 *mc)
693 {
694 	struct net_device *dev = mc->idev->dev;
695 	char buf[MAX_ADDR_LEN];
696 
697 	if (IPV6_ADDR_MC_SCOPE(&mc->mca_addr) <
698 	    IPV6_ADDR_SCOPE_LINKLOCAL)
699 		return;
700 
701 	spin_lock_bh(&mc->mca_lock);
702 	if (mc->mca_flags&MAF_LOADED) {
703 		mc->mca_flags &= ~MAF_LOADED;
704 		if (ndisc_mc_map(&mc->mca_addr, buf, dev, 0) == 0)
705 			dev_mc_del(dev, buf);
706 	}
707 
708 	spin_unlock_bh(&mc->mca_lock);
709 	if (mc->mca_flags & MAF_NOREPORT)
710 		return;
711 
712 	if (!mc->idev->dead)
713 		igmp6_leave_group(mc);
714 
715 	spin_lock_bh(&mc->mca_lock);
716 	if (del_timer(&mc->mca_timer))
717 		refcount_dec(&mc->mca_refcnt);
718 	spin_unlock_bh(&mc->mca_lock);
719 }
720 
721 /*
722  * deleted ifmcaddr6 manipulation
723  */
724 static void mld_add_delrec(struct inet6_dev *idev, struct ifmcaddr6 *im)
725 {
726 	struct ifmcaddr6 *pmc;
727 
728 	/* this is an "ifmcaddr6" for convenience; only the fields below
729 	 * are actually used. In particular, the refcnt and users are not
730 	 * used for management of the delete list. Using the same structure
731 	 * for deleted items allows change reports to use common code with
732 	 * non-deleted or query-response MCA's.
733 	 */
734 	pmc = kzalloc(sizeof(*pmc), GFP_ATOMIC);
735 	if (!pmc)
736 		return;
737 
738 	spin_lock_bh(&im->mca_lock);
739 	spin_lock_init(&pmc->mca_lock);
740 	pmc->idev = im->idev;
741 	in6_dev_hold(idev);
742 	pmc->mca_addr = im->mca_addr;
743 	pmc->mca_crcount = idev->mc_qrv;
744 	pmc->mca_sfmode = im->mca_sfmode;
745 	if (pmc->mca_sfmode == MCAST_INCLUDE) {
746 		struct ip6_sf_list *psf;
747 
748 		pmc->mca_tomb = im->mca_tomb;
749 		pmc->mca_sources = im->mca_sources;
750 		im->mca_tomb = im->mca_sources = NULL;
751 		for (psf = pmc->mca_sources; psf; psf = psf->sf_next)
752 			psf->sf_crcount = pmc->mca_crcount;
753 	}
754 	spin_unlock_bh(&im->mca_lock);
755 
756 	spin_lock_bh(&idev->mc_lock);
757 	pmc->next = idev->mc_tomb;
758 	idev->mc_tomb = pmc;
759 	spin_unlock_bh(&idev->mc_lock);
760 }
761 
762 static void mld_del_delrec(struct inet6_dev *idev, struct ifmcaddr6 *im)
763 {
764 	struct ifmcaddr6 *pmc, *pmc_prev;
765 	struct ip6_sf_list *psf;
766 	struct in6_addr *pmca = &im->mca_addr;
767 
768 	spin_lock_bh(&idev->mc_lock);
769 	pmc_prev = NULL;
770 	for (pmc = idev->mc_tomb; pmc; pmc = pmc->next) {
771 		if (ipv6_addr_equal(&pmc->mca_addr, pmca))
772 			break;
773 		pmc_prev = pmc;
774 	}
775 	if (pmc) {
776 		if (pmc_prev)
777 			pmc_prev->next = pmc->next;
778 		else
779 			idev->mc_tomb = pmc->next;
780 	}
781 	spin_unlock_bh(&idev->mc_lock);
782 
783 	spin_lock_bh(&im->mca_lock);
784 	if (pmc) {
785 		im->idev = pmc->idev;
786 		if (im->mca_sfmode == MCAST_INCLUDE) {
787 			swap(im->mca_tomb, pmc->mca_tomb);
788 			swap(im->mca_sources, pmc->mca_sources);
789 			for (psf = im->mca_sources; psf; psf = psf->sf_next)
790 				psf->sf_crcount = idev->mc_qrv;
791 		} else {
792 			im->mca_crcount = idev->mc_qrv;
793 		}
794 		in6_dev_put(pmc->idev);
795 		ip6_mc_clear_src(pmc);
796 		kfree(pmc);
797 	}
798 	spin_unlock_bh(&im->mca_lock);
799 }
800 
801 static void mld_clear_delrec(struct inet6_dev *idev)
802 {
803 	struct ifmcaddr6 *pmc, *nextpmc;
804 
805 	spin_lock_bh(&idev->mc_lock);
806 	pmc = idev->mc_tomb;
807 	idev->mc_tomb = NULL;
808 	spin_unlock_bh(&idev->mc_lock);
809 
810 	for (; pmc; pmc = nextpmc) {
811 		nextpmc = pmc->next;
812 		ip6_mc_clear_src(pmc);
813 		in6_dev_put(pmc->idev);
814 		kfree(pmc);
815 	}
816 
817 	/* clear dead sources, too */
818 	read_lock_bh(&idev->lock);
819 	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
820 		struct ip6_sf_list *psf, *psf_next;
821 
822 		spin_lock_bh(&pmc->mca_lock);
823 		psf = pmc->mca_tomb;
824 		pmc->mca_tomb = NULL;
825 		spin_unlock_bh(&pmc->mca_lock);
826 		for (; psf; psf = psf_next) {
827 			psf_next = psf->sf_next;
828 			kfree(psf);
829 		}
830 	}
831 	read_unlock_bh(&idev->lock);
832 }
833 
834 static void mca_get(struct ifmcaddr6 *mc)
835 {
836 	refcount_inc(&mc->mca_refcnt);
837 }
838 
839 static void ma_put(struct ifmcaddr6 *mc)
840 {
841 	if (refcount_dec_and_test(&mc->mca_refcnt)) {
842 		in6_dev_put(mc->idev);
843 		kfree(mc);
844 	}
845 }
846 
847 static struct ifmcaddr6 *mca_alloc(struct inet6_dev *idev,
848 				   const struct in6_addr *addr,
849 				   unsigned int mode)
850 {
851 	struct ifmcaddr6 *mc;
852 
853 	mc = kzalloc(sizeof(*mc), GFP_ATOMIC);
854 	if (!mc)
855 		return NULL;
856 
857 	timer_setup(&mc->mca_timer, igmp6_timer_handler, 0);
858 
859 	mc->mca_addr = *addr;
860 	mc->idev = idev; /* reference taken by caller */
861 	mc->mca_users = 1;
862 	/* mca_stamp should be updated upon changes */
863 	mc->mca_cstamp = mc->mca_tstamp = jiffies;
864 	refcount_set(&mc->mca_refcnt, 1);
865 	spin_lock_init(&mc->mca_lock);
866 
867 	mc->mca_sfmode = mode;
868 	mc->mca_sfcount[mode] = 1;
869 
870 	if (ipv6_addr_is_ll_all_nodes(&mc->mca_addr) ||
871 	    IPV6_ADDR_MC_SCOPE(&mc->mca_addr) < IPV6_ADDR_SCOPE_LINKLOCAL)
872 		mc->mca_flags |= MAF_NOREPORT;
873 
874 	return mc;
875 }
876 
877 /*
878  *	device multicast group inc (add if not found)
879  */
880 static int __ipv6_dev_mc_inc(struct net_device *dev,
881 			     const struct in6_addr *addr, unsigned int mode)
882 {
883 	struct ifmcaddr6 *mc;
884 	struct inet6_dev *idev;
885 
886 	ASSERT_RTNL();
887 
888 	/* we need to take a reference on idev */
889 	idev = in6_dev_get(dev);
890 
891 	if (!idev)
892 		return -EINVAL;
893 
894 	write_lock_bh(&idev->lock);
895 	if (idev->dead) {
896 		write_unlock_bh(&idev->lock);
897 		in6_dev_put(idev);
898 		return -ENODEV;
899 	}
900 
901 	for (mc = idev->mc_list; mc; mc = mc->next) {
902 		if (ipv6_addr_equal(&mc->mca_addr, addr)) {
903 			mc->mca_users++;
904 			write_unlock_bh(&idev->lock);
905 			ip6_mc_add_src(idev, &mc->mca_addr, mode, 0, NULL, 0);
906 			in6_dev_put(idev);
907 			return 0;
908 		}
909 	}
910 
911 	mc = mca_alloc(idev, addr, mode);
912 	if (!mc) {
913 		write_unlock_bh(&idev->lock);
914 		in6_dev_put(idev);
915 		return -ENOMEM;
916 	}
917 
918 	mc->next = idev->mc_list;
919 	idev->mc_list = mc;
920 
921 	/* Hold this for the code below before we unlock,
922 	 * it is already exposed via idev->mc_list.
923 	 */
924 	mca_get(mc);
925 	write_unlock_bh(&idev->lock);
926 
927 	mld_del_delrec(idev, mc);
928 	igmp6_group_added(mc);
929 	ma_put(mc);
930 	return 0;
931 }
932 
933 int ipv6_dev_mc_inc(struct net_device *dev, const struct in6_addr *addr)
934 {
935 	return __ipv6_dev_mc_inc(dev, addr, MCAST_EXCLUDE);
936 }
937 EXPORT_SYMBOL(ipv6_dev_mc_inc);
938 
939 /*
940  *	device multicast group del
941  */
942 int __ipv6_dev_mc_dec(struct inet6_dev *idev, const struct in6_addr *addr)
943 {
944 	struct ifmcaddr6 *ma, **map;
945 
946 	ASSERT_RTNL();
947 
948 	write_lock_bh(&idev->lock);
949 	for (map = &idev->mc_list; (ma = *map) != NULL; map = &ma->next) {
950 		if (ipv6_addr_equal(&ma->mca_addr, addr)) {
951 			if (--ma->mca_users == 0) {
952 				*map = ma->next;
953 				write_unlock_bh(&idev->lock);
954 
955 				igmp6_group_dropped(ma);
956 				ip6_mc_clear_src(ma);
957 
958 				ma_put(ma);
959 				return 0;
960 			}
961 			write_unlock_bh(&idev->lock);
962 			return 0;
963 		}
964 	}
965 	write_unlock_bh(&idev->lock);
966 
967 	return -ENOENT;
968 }
969 
970 int ipv6_dev_mc_dec(struct net_device *dev, const struct in6_addr *addr)
971 {
972 	struct inet6_dev *idev;
973 	int err;
974 
975 	ASSERT_RTNL();
976 
977 	idev = __in6_dev_get(dev);
978 	if (!idev)
979 		err = -ENODEV;
980 	else
981 		err = __ipv6_dev_mc_dec(idev, addr);
982 
983 	return err;
984 }
985 EXPORT_SYMBOL(ipv6_dev_mc_dec);
986 
987 /*
988  *	check if the interface/address pair is valid
989  */
990 bool ipv6_chk_mcast_addr(struct net_device *dev, const struct in6_addr *group,
991 			 const struct in6_addr *src_addr)
992 {
993 	struct inet6_dev *idev;
994 	struct ifmcaddr6 *mc;
995 	bool rv = false;
996 
997 	rcu_read_lock();
998 	idev = __in6_dev_get(dev);
999 	if (idev) {
1000 		read_lock_bh(&idev->lock);
1001 		for (mc = idev->mc_list; mc; mc = mc->next) {
1002 			if (ipv6_addr_equal(&mc->mca_addr, group))
1003 				break;
1004 		}
1005 		if (mc) {
1006 			if (src_addr && !ipv6_addr_any(src_addr)) {
1007 				struct ip6_sf_list *psf;
1008 
1009 				spin_lock_bh(&mc->mca_lock);
1010 				for (psf = mc->mca_sources; psf; psf = psf->sf_next) {
1011 					if (ipv6_addr_equal(&psf->sf_addr, src_addr))
1012 						break;
1013 				}
1014 				if (psf)
1015 					rv = psf->sf_count[MCAST_INCLUDE] ||
1016 						psf->sf_count[MCAST_EXCLUDE] !=
1017 						mc->mca_sfcount[MCAST_EXCLUDE];
1018 				else
1019 					rv = mc->mca_sfcount[MCAST_EXCLUDE] != 0;
1020 				spin_unlock_bh(&mc->mca_lock);
1021 			} else
1022 				rv = true; /* don't filter unspecified source */
1023 		}
1024 		read_unlock_bh(&idev->lock);
1025 	}
1026 	rcu_read_unlock();
1027 	return rv;
1028 }
1029 
1030 static void mld_gq_start_timer(struct inet6_dev *idev)
1031 {
1032 	unsigned long tv = prandom_u32() % idev->mc_maxdelay;
1033 
1034 	idev->mc_gq_running = 1;
1035 	if (!mod_timer(&idev->mc_gq_timer, jiffies+tv+2))
1036 		in6_dev_hold(idev);
1037 }
1038 
1039 static void mld_gq_stop_timer(struct inet6_dev *idev)
1040 {
1041 	idev->mc_gq_running = 0;
1042 	if (del_timer(&idev->mc_gq_timer))
1043 		__in6_dev_put(idev);
1044 }
1045 
1046 static void mld_ifc_start_timer(struct inet6_dev *idev, unsigned long delay)
1047 {
1048 	unsigned long tv = prandom_u32() % delay;
1049 
1050 	if (!mod_timer(&idev->mc_ifc_timer, jiffies+tv+2))
1051 		in6_dev_hold(idev);
1052 }
1053 
1054 static void mld_ifc_stop_timer(struct inet6_dev *idev)
1055 {
1056 	idev->mc_ifc_count = 0;
1057 	if (del_timer(&idev->mc_ifc_timer))
1058 		__in6_dev_put(idev);
1059 }
1060 
1061 static void mld_dad_start_timer(struct inet6_dev *idev, unsigned long delay)
1062 {
1063 	unsigned long tv = prandom_u32() % delay;
1064 
1065 	if (!mod_timer(&idev->mc_dad_timer, jiffies+tv+2))
1066 		in6_dev_hold(idev);
1067 }
1068 
1069 static void mld_dad_stop_timer(struct inet6_dev *idev)
1070 {
1071 	if (del_timer(&idev->mc_dad_timer))
1072 		__in6_dev_put(idev);
1073 }
1074 
1075 /*
1076  *	IGMP handling (alias multicast ICMPv6 messages)
1077  */
1078 
1079 static void igmp6_group_queried(struct ifmcaddr6 *ma, unsigned long resptime)
1080 {
1081 	unsigned long delay = resptime;
1082 
1083 	/* Do not start timer for these addresses */
1084 	if (ipv6_addr_is_ll_all_nodes(&ma->mca_addr) ||
1085 	    IPV6_ADDR_MC_SCOPE(&ma->mca_addr) < IPV6_ADDR_SCOPE_LINKLOCAL)
1086 		return;
1087 
1088 	if (del_timer(&ma->mca_timer)) {
1089 		refcount_dec(&ma->mca_refcnt);
1090 		delay = ma->mca_timer.expires - jiffies;
1091 	}
1092 
1093 	if (delay >= resptime)
1094 		delay = prandom_u32() % resptime;
1095 
1096 	ma->mca_timer.expires = jiffies + delay;
1097 	if (!mod_timer(&ma->mca_timer, jiffies + delay))
1098 		refcount_inc(&ma->mca_refcnt);
1099 	ma->mca_flags |= MAF_TIMER_RUNNING;
1100 }
1101 
1102 /* mark EXCLUDE-mode sources */
1103 static bool mld_xmarksources(struct ifmcaddr6 *pmc, int nsrcs,
1104 			     const struct in6_addr *srcs)
1105 {
1106 	struct ip6_sf_list *psf;
1107 	int i, scount;
1108 
1109 	scount = 0;
1110 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
1111 		if (scount == nsrcs)
1112 			break;
1113 		for (i = 0; i < nsrcs; i++) {
1114 			/* skip inactive filters */
1115 			if (psf->sf_count[MCAST_INCLUDE] ||
1116 			    pmc->mca_sfcount[MCAST_EXCLUDE] !=
1117 			    psf->sf_count[MCAST_EXCLUDE])
1118 				break;
1119 			if (ipv6_addr_equal(&srcs[i], &psf->sf_addr)) {
1120 				scount++;
1121 				break;
1122 			}
1123 		}
1124 	}
1125 	pmc->mca_flags &= ~MAF_GSQUERY;
1126 	if (scount == nsrcs)	/* all sources excluded */
1127 		return false;
1128 	return true;
1129 }
1130 
1131 static bool mld_marksources(struct ifmcaddr6 *pmc, int nsrcs,
1132 			    const struct in6_addr *srcs)
1133 {
1134 	struct ip6_sf_list *psf;
1135 	int i, scount;
1136 
1137 	if (pmc->mca_sfmode == MCAST_EXCLUDE)
1138 		return mld_xmarksources(pmc, nsrcs, srcs);
1139 
1140 	/* mark INCLUDE-mode sources */
1141 
1142 	scount = 0;
1143 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
1144 		if (scount == nsrcs)
1145 			break;
1146 		for (i = 0; i < nsrcs; i++) {
1147 			if (ipv6_addr_equal(&srcs[i], &psf->sf_addr)) {
1148 				psf->sf_gsresp = 1;
1149 				scount++;
1150 				break;
1151 			}
1152 		}
1153 	}
1154 	if (!scount) {
1155 		pmc->mca_flags &= ~MAF_GSQUERY;
1156 		return false;
1157 	}
1158 	pmc->mca_flags |= MAF_GSQUERY;
1159 	return true;
1160 }
1161 
1162 static int mld_force_mld_version(const struct inet6_dev *idev)
1163 {
1164 	/* Normally, both are 0 here. If enforcement to a particular is
1165 	 * being used, individual device enforcement will have a lower
1166 	 * precedence over 'all' device (.../conf/all/force_mld_version).
1167 	 */
1168 
1169 	if (dev_net(idev->dev)->ipv6.devconf_all->force_mld_version != 0)
1170 		return dev_net(idev->dev)->ipv6.devconf_all->force_mld_version;
1171 	else
1172 		return idev->cnf.force_mld_version;
1173 }
1174 
1175 static bool mld_in_v2_mode_only(const struct inet6_dev *idev)
1176 {
1177 	return mld_force_mld_version(idev) == 2;
1178 }
1179 
1180 static bool mld_in_v1_mode_only(const struct inet6_dev *idev)
1181 {
1182 	return mld_force_mld_version(idev) == 1;
1183 }
1184 
1185 static bool mld_in_v1_mode(const struct inet6_dev *idev)
1186 {
1187 	if (mld_in_v2_mode_only(idev))
1188 		return false;
1189 	if (mld_in_v1_mode_only(idev))
1190 		return true;
1191 	if (idev->mc_v1_seen && time_before(jiffies, idev->mc_v1_seen))
1192 		return true;
1193 
1194 	return false;
1195 }
1196 
1197 static void mld_set_v1_mode(struct inet6_dev *idev)
1198 {
1199 	/* RFC3810, relevant sections:
1200 	 *  - 9.1. Robustness Variable
1201 	 *  - 9.2. Query Interval
1202 	 *  - 9.3. Query Response Interval
1203 	 *  - 9.12. Older Version Querier Present Timeout
1204 	 */
1205 	unsigned long switchback;
1206 
1207 	switchback = (idev->mc_qrv * idev->mc_qi) + idev->mc_qri;
1208 
1209 	idev->mc_v1_seen = jiffies + switchback;
1210 }
1211 
1212 static void mld_update_qrv(struct inet6_dev *idev,
1213 			   const struct mld2_query *mlh2)
1214 {
1215 	/* RFC3810, relevant sections:
1216 	 *  - 5.1.8. QRV (Querier's Robustness Variable)
1217 	 *  - 9.1. Robustness Variable
1218 	 */
1219 
1220 	/* The value of the Robustness Variable MUST NOT be zero,
1221 	 * and SHOULD NOT be one. Catch this here if we ever run
1222 	 * into such a case in future.
1223 	 */
1224 	const int min_qrv = min(MLD_QRV_DEFAULT, sysctl_mld_qrv);
1225 	WARN_ON(idev->mc_qrv == 0);
1226 
1227 	if (mlh2->mld2q_qrv > 0)
1228 		idev->mc_qrv = mlh2->mld2q_qrv;
1229 
1230 	if (unlikely(idev->mc_qrv < min_qrv)) {
1231 		net_warn_ratelimited("IPv6: MLD: clamping QRV from %u to %u!\n",
1232 				     idev->mc_qrv, min_qrv);
1233 		idev->mc_qrv = min_qrv;
1234 	}
1235 }
1236 
1237 static void mld_update_qi(struct inet6_dev *idev,
1238 			  const struct mld2_query *mlh2)
1239 {
1240 	/* RFC3810, relevant sections:
1241 	 *  - 5.1.9. QQIC (Querier's Query Interval Code)
1242 	 *  - 9.2. Query Interval
1243 	 *  - 9.12. Older Version Querier Present Timeout
1244 	 *    (the [Query Interval] in the last Query received)
1245 	 */
1246 	unsigned long mc_qqi;
1247 
1248 	if (mlh2->mld2q_qqic < 128) {
1249 		mc_qqi = mlh2->mld2q_qqic;
1250 	} else {
1251 		unsigned long mc_man, mc_exp;
1252 
1253 		mc_exp = MLDV2_QQIC_EXP(mlh2->mld2q_qqic);
1254 		mc_man = MLDV2_QQIC_MAN(mlh2->mld2q_qqic);
1255 
1256 		mc_qqi = (mc_man | 0x10) << (mc_exp + 3);
1257 	}
1258 
1259 	idev->mc_qi = mc_qqi * HZ;
1260 }
1261 
1262 static void mld_update_qri(struct inet6_dev *idev,
1263 			   const struct mld2_query *mlh2)
1264 {
1265 	/* RFC3810, relevant sections:
1266 	 *  - 5.1.3. Maximum Response Code
1267 	 *  - 9.3. Query Response Interval
1268 	 */
1269 	idev->mc_qri = msecs_to_jiffies(mldv2_mrc(mlh2));
1270 }
1271 
1272 static int mld_process_v1(struct inet6_dev *idev, struct mld_msg *mld,
1273 			  unsigned long *max_delay, bool v1_query)
1274 {
1275 	unsigned long mldv1_md;
1276 
1277 	/* Ignore v1 queries */
1278 	if (mld_in_v2_mode_only(idev))
1279 		return -EINVAL;
1280 
1281 	mldv1_md = ntohs(mld->mld_maxdelay);
1282 
1283 	/* When in MLDv1 fallback and a MLDv2 router start-up being
1284 	 * unaware of current MLDv1 operation, the MRC == MRD mapping
1285 	 * only works when the exponential algorithm is not being
1286 	 * used (as MLDv1 is unaware of such things).
1287 	 *
1288 	 * According to the RFC author, the MLDv2 implementations
1289 	 * he's aware of all use a MRC < 32768 on start up queries.
1290 	 *
1291 	 * Thus, should we *ever* encounter something else larger
1292 	 * than that, just assume the maximum possible within our
1293 	 * reach.
1294 	 */
1295 	if (!v1_query)
1296 		mldv1_md = min(mldv1_md, MLDV1_MRD_MAX_COMPAT);
1297 
1298 	*max_delay = max(msecs_to_jiffies(mldv1_md), 1UL);
1299 
1300 	/* MLDv1 router present: we need to go into v1 mode *only*
1301 	 * when an MLDv1 query is received as per section 9.12. of
1302 	 * RFC3810! And we know from RFC2710 section 3.7 that MLDv1
1303 	 * queries MUST be of exactly 24 octets.
1304 	 */
1305 	if (v1_query)
1306 		mld_set_v1_mode(idev);
1307 
1308 	/* cancel MLDv2 report timer */
1309 	mld_gq_stop_timer(idev);
1310 	/* cancel the interface change timer */
1311 	mld_ifc_stop_timer(idev);
1312 	/* clear deleted report items */
1313 	mld_clear_delrec(idev);
1314 
1315 	return 0;
1316 }
1317 
1318 static int mld_process_v2(struct inet6_dev *idev, struct mld2_query *mld,
1319 			  unsigned long *max_delay)
1320 {
1321 	*max_delay = max(msecs_to_jiffies(mldv2_mrc(mld)), 1UL);
1322 
1323 	mld_update_qrv(idev, mld);
1324 	mld_update_qi(idev, mld);
1325 	mld_update_qri(idev, mld);
1326 
1327 	idev->mc_maxdelay = *max_delay;
1328 
1329 	return 0;
1330 }
1331 
1332 /* called with rcu_read_lock() */
1333 int igmp6_event_query(struct sk_buff *skb)
1334 {
1335 	struct mld2_query *mlh2 = NULL;
1336 	struct ifmcaddr6 *ma;
1337 	const struct in6_addr *group;
1338 	unsigned long max_delay;
1339 	struct inet6_dev *idev;
1340 	struct mld_msg *mld;
1341 	int group_type;
1342 	int mark = 0;
1343 	int len, err;
1344 
1345 	if (!pskb_may_pull(skb, sizeof(struct in6_addr)))
1346 		return -EINVAL;
1347 
1348 	/* compute payload length excluding extension headers */
1349 	len = ntohs(ipv6_hdr(skb)->payload_len) + sizeof(struct ipv6hdr);
1350 	len -= skb_network_header_len(skb);
1351 
1352 	/* RFC3810 6.2
1353 	 * Upon reception of an MLD message that contains a Query, the node
1354 	 * checks if the source address of the message is a valid link-local
1355 	 * address, if the Hop Limit is set to 1, and if the Router Alert
1356 	 * option is present in the Hop-By-Hop Options header of the IPv6
1357 	 * packet.  If any of these checks fails, the packet is dropped.
1358 	 */
1359 	if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL) ||
1360 	    ipv6_hdr(skb)->hop_limit != 1 ||
1361 	    !(IP6CB(skb)->flags & IP6SKB_ROUTERALERT) ||
1362 	    IP6CB(skb)->ra != htons(IPV6_OPT_ROUTERALERT_MLD))
1363 		return -EINVAL;
1364 
1365 	idev = __in6_dev_get(skb->dev);
1366 	if (!idev)
1367 		return 0;
1368 
1369 	mld = (struct mld_msg *)icmp6_hdr(skb);
1370 	group = &mld->mld_mca;
1371 	group_type = ipv6_addr_type(group);
1372 
1373 	if (group_type != IPV6_ADDR_ANY &&
1374 	    !(group_type&IPV6_ADDR_MULTICAST))
1375 		return -EINVAL;
1376 
1377 	if (len < MLD_V1_QUERY_LEN) {
1378 		return -EINVAL;
1379 	} else if (len == MLD_V1_QUERY_LEN || mld_in_v1_mode(idev)) {
1380 		err = mld_process_v1(idev, mld, &max_delay,
1381 				     len == MLD_V1_QUERY_LEN);
1382 		if (err < 0)
1383 			return err;
1384 	} else if (len >= MLD_V2_QUERY_LEN_MIN) {
1385 		int srcs_offset = sizeof(struct mld2_query) -
1386 				  sizeof(struct icmp6hdr);
1387 
1388 		if (!pskb_may_pull(skb, srcs_offset))
1389 			return -EINVAL;
1390 
1391 		mlh2 = (struct mld2_query *)skb_transport_header(skb);
1392 
1393 		err = mld_process_v2(idev, mlh2, &max_delay);
1394 		if (err < 0)
1395 			return err;
1396 
1397 		if (group_type == IPV6_ADDR_ANY) { /* general query */
1398 			if (mlh2->mld2q_nsrcs)
1399 				return -EINVAL; /* no sources allowed */
1400 
1401 			mld_gq_start_timer(idev);
1402 			return 0;
1403 		}
1404 		/* mark sources to include, if group & source-specific */
1405 		if (mlh2->mld2q_nsrcs != 0) {
1406 			if (!pskb_may_pull(skb, srcs_offset +
1407 			    ntohs(mlh2->mld2q_nsrcs) * sizeof(struct in6_addr)))
1408 				return -EINVAL;
1409 
1410 			mlh2 = (struct mld2_query *)skb_transport_header(skb);
1411 			mark = 1;
1412 		}
1413 	} else {
1414 		return -EINVAL;
1415 	}
1416 
1417 	read_lock_bh(&idev->lock);
1418 	if (group_type == IPV6_ADDR_ANY) {
1419 		for (ma = idev->mc_list; ma; ma = ma->next) {
1420 			spin_lock_bh(&ma->mca_lock);
1421 			igmp6_group_queried(ma, max_delay);
1422 			spin_unlock_bh(&ma->mca_lock);
1423 		}
1424 	} else {
1425 		for (ma = idev->mc_list; ma; ma = ma->next) {
1426 			if (!ipv6_addr_equal(group, &ma->mca_addr))
1427 				continue;
1428 			spin_lock_bh(&ma->mca_lock);
1429 			if (ma->mca_flags & MAF_TIMER_RUNNING) {
1430 				/* gsquery <- gsquery && mark */
1431 				if (!mark)
1432 					ma->mca_flags &= ~MAF_GSQUERY;
1433 			} else {
1434 				/* gsquery <- mark */
1435 				if (mark)
1436 					ma->mca_flags |= MAF_GSQUERY;
1437 				else
1438 					ma->mca_flags &= ~MAF_GSQUERY;
1439 			}
1440 			if (!(ma->mca_flags & MAF_GSQUERY) ||
1441 			    mld_marksources(ma, ntohs(mlh2->mld2q_nsrcs), mlh2->mld2q_srcs))
1442 				igmp6_group_queried(ma, max_delay);
1443 			spin_unlock_bh(&ma->mca_lock);
1444 			break;
1445 		}
1446 	}
1447 	read_unlock_bh(&idev->lock);
1448 
1449 	return 0;
1450 }
1451 
1452 /* called with rcu_read_lock() */
1453 int igmp6_event_report(struct sk_buff *skb)
1454 {
1455 	struct ifmcaddr6 *ma;
1456 	struct inet6_dev *idev;
1457 	struct mld_msg *mld;
1458 	int addr_type;
1459 
1460 	/* Our own report looped back. Ignore it. */
1461 	if (skb->pkt_type == PACKET_LOOPBACK)
1462 		return 0;
1463 
1464 	/* send our report if the MC router may not have heard this report */
1465 	if (skb->pkt_type != PACKET_MULTICAST &&
1466 	    skb->pkt_type != PACKET_BROADCAST)
1467 		return 0;
1468 
1469 	if (!pskb_may_pull(skb, sizeof(*mld) - sizeof(struct icmp6hdr)))
1470 		return -EINVAL;
1471 
1472 	mld = (struct mld_msg *)icmp6_hdr(skb);
1473 
1474 	/* Drop reports with not link local source */
1475 	addr_type = ipv6_addr_type(&ipv6_hdr(skb)->saddr);
1476 	if (addr_type != IPV6_ADDR_ANY &&
1477 	    !(addr_type&IPV6_ADDR_LINKLOCAL))
1478 		return -EINVAL;
1479 
1480 	idev = __in6_dev_get(skb->dev);
1481 	if (!idev)
1482 		return -ENODEV;
1483 
1484 	/*
1485 	 *	Cancel the timer for this group
1486 	 */
1487 
1488 	read_lock_bh(&idev->lock);
1489 	for (ma = idev->mc_list; ma; ma = ma->next) {
1490 		if (ipv6_addr_equal(&ma->mca_addr, &mld->mld_mca)) {
1491 			spin_lock(&ma->mca_lock);
1492 			if (del_timer(&ma->mca_timer))
1493 				refcount_dec(&ma->mca_refcnt);
1494 			ma->mca_flags &= ~(MAF_LAST_REPORTER|MAF_TIMER_RUNNING);
1495 			spin_unlock(&ma->mca_lock);
1496 			break;
1497 		}
1498 	}
1499 	read_unlock_bh(&idev->lock);
1500 	return 0;
1501 }
1502 
1503 static bool is_in(struct ifmcaddr6 *pmc, struct ip6_sf_list *psf, int type,
1504 		  int gdeleted, int sdeleted)
1505 {
1506 	switch (type) {
1507 	case MLD2_MODE_IS_INCLUDE:
1508 	case MLD2_MODE_IS_EXCLUDE:
1509 		if (gdeleted || sdeleted)
1510 			return false;
1511 		if (!((pmc->mca_flags & MAF_GSQUERY) && !psf->sf_gsresp)) {
1512 			if (pmc->mca_sfmode == MCAST_INCLUDE)
1513 				return true;
1514 			/* don't include if this source is excluded
1515 			 * in all filters
1516 			 */
1517 			if (psf->sf_count[MCAST_INCLUDE])
1518 				return type == MLD2_MODE_IS_INCLUDE;
1519 			return pmc->mca_sfcount[MCAST_EXCLUDE] ==
1520 				psf->sf_count[MCAST_EXCLUDE];
1521 		}
1522 		return false;
1523 	case MLD2_CHANGE_TO_INCLUDE:
1524 		if (gdeleted || sdeleted)
1525 			return false;
1526 		return psf->sf_count[MCAST_INCLUDE] != 0;
1527 	case MLD2_CHANGE_TO_EXCLUDE:
1528 		if (gdeleted || sdeleted)
1529 			return false;
1530 		if (pmc->mca_sfcount[MCAST_EXCLUDE] == 0 ||
1531 		    psf->sf_count[MCAST_INCLUDE])
1532 			return false;
1533 		return pmc->mca_sfcount[MCAST_EXCLUDE] ==
1534 			psf->sf_count[MCAST_EXCLUDE];
1535 	case MLD2_ALLOW_NEW_SOURCES:
1536 		if (gdeleted || !psf->sf_crcount)
1537 			return false;
1538 		return (pmc->mca_sfmode == MCAST_INCLUDE) ^ sdeleted;
1539 	case MLD2_BLOCK_OLD_SOURCES:
1540 		if (pmc->mca_sfmode == MCAST_INCLUDE)
1541 			return gdeleted || (psf->sf_crcount && sdeleted);
1542 		return psf->sf_crcount && !gdeleted && !sdeleted;
1543 	}
1544 	return false;
1545 }
1546 
1547 static int
1548 mld_scount(struct ifmcaddr6 *pmc, int type, int gdeleted, int sdeleted)
1549 {
1550 	struct ip6_sf_list *psf;
1551 	int scount = 0;
1552 
1553 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
1554 		if (!is_in(pmc, psf, type, gdeleted, sdeleted))
1555 			continue;
1556 		scount++;
1557 	}
1558 	return scount;
1559 }
1560 
1561 static void ip6_mc_hdr(struct sock *sk, struct sk_buff *skb,
1562 		       struct net_device *dev,
1563 		       const struct in6_addr *saddr,
1564 		       const struct in6_addr *daddr,
1565 		       int proto, int len)
1566 {
1567 	struct ipv6hdr *hdr;
1568 
1569 	skb->protocol = htons(ETH_P_IPV6);
1570 	skb->dev = dev;
1571 
1572 	skb_reset_network_header(skb);
1573 	skb_put(skb, sizeof(struct ipv6hdr));
1574 	hdr = ipv6_hdr(skb);
1575 
1576 	ip6_flow_hdr(hdr, 0, 0);
1577 
1578 	hdr->payload_len = htons(len);
1579 	hdr->nexthdr = proto;
1580 	hdr->hop_limit = inet6_sk(sk)->hop_limit;
1581 
1582 	hdr->saddr = *saddr;
1583 	hdr->daddr = *daddr;
1584 }
1585 
1586 static struct sk_buff *mld_newpack(struct inet6_dev *idev, unsigned int mtu)
1587 {
1588 	struct net_device *dev = idev->dev;
1589 	struct net *net = dev_net(dev);
1590 	struct sock *sk = net->ipv6.igmp_sk;
1591 	struct sk_buff *skb;
1592 	struct mld2_report *pmr;
1593 	struct in6_addr addr_buf;
1594 	const struct in6_addr *saddr;
1595 	int hlen = LL_RESERVED_SPACE(dev);
1596 	int tlen = dev->needed_tailroom;
1597 	unsigned int size = mtu + hlen + tlen;
1598 	int err;
1599 	u8 ra[8] = { IPPROTO_ICMPV6, 0,
1600 		     IPV6_TLV_ROUTERALERT, 2, 0, 0,
1601 		     IPV6_TLV_PADN, 0 };
1602 
1603 	/* we assume size > sizeof(ra) here */
1604 	/* limit our allocations to order-0 page */
1605 	size = min_t(int, size, SKB_MAX_ORDER(0, 0));
1606 	skb = sock_alloc_send_skb(sk, size, 1, &err);
1607 
1608 	if (!skb)
1609 		return NULL;
1610 
1611 	skb->priority = TC_PRIO_CONTROL;
1612 	skb_reserve(skb, hlen);
1613 	skb_tailroom_reserve(skb, mtu, tlen);
1614 
1615 	if (__ipv6_get_lladdr(idev, &addr_buf, IFA_F_TENTATIVE)) {
1616 		/* <draft-ietf-magma-mld-source-05.txt>:
1617 		 * use unspecified address as the source address
1618 		 * when a valid link-local address is not available.
1619 		 */
1620 		saddr = &in6addr_any;
1621 	} else
1622 		saddr = &addr_buf;
1623 
1624 	ip6_mc_hdr(sk, skb, dev, saddr, &mld2_all_mcr, NEXTHDR_HOP, 0);
1625 
1626 	skb_put_data(skb, ra, sizeof(ra));
1627 
1628 	skb_set_transport_header(skb, skb_tail_pointer(skb) - skb->data);
1629 	skb_put(skb, sizeof(*pmr));
1630 	pmr = (struct mld2_report *)skb_transport_header(skb);
1631 	pmr->mld2r_type = ICMPV6_MLD2_REPORT;
1632 	pmr->mld2r_resv1 = 0;
1633 	pmr->mld2r_cksum = 0;
1634 	pmr->mld2r_resv2 = 0;
1635 	pmr->mld2r_ngrec = 0;
1636 	return skb;
1637 }
1638 
1639 static void mld_sendpack(struct sk_buff *skb)
1640 {
1641 	struct ipv6hdr *pip6 = ipv6_hdr(skb);
1642 	struct mld2_report *pmr =
1643 			      (struct mld2_report *)skb_transport_header(skb);
1644 	int payload_len, mldlen;
1645 	struct inet6_dev *idev;
1646 	struct net *net = dev_net(skb->dev);
1647 	int err;
1648 	struct flowi6 fl6;
1649 	struct dst_entry *dst;
1650 
1651 	rcu_read_lock();
1652 	idev = __in6_dev_get(skb->dev);
1653 	IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len);
1654 
1655 	payload_len = (skb_tail_pointer(skb) - skb_network_header(skb)) -
1656 		sizeof(*pip6);
1657 	mldlen = skb_tail_pointer(skb) - skb_transport_header(skb);
1658 	pip6->payload_len = htons(payload_len);
1659 
1660 	pmr->mld2r_cksum = csum_ipv6_magic(&pip6->saddr, &pip6->daddr, mldlen,
1661 					   IPPROTO_ICMPV6,
1662 					   csum_partial(skb_transport_header(skb),
1663 							mldlen, 0));
1664 
1665 	icmpv6_flow_init(net->ipv6.igmp_sk, &fl6, ICMPV6_MLD2_REPORT,
1666 			 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
1667 			 skb->dev->ifindex);
1668 	dst = icmp6_dst_alloc(skb->dev, &fl6);
1669 
1670 	err = 0;
1671 	if (IS_ERR(dst)) {
1672 		err = PTR_ERR(dst);
1673 		dst = NULL;
1674 	}
1675 	skb_dst_set(skb, dst);
1676 	if (err)
1677 		goto err_out;
1678 
1679 	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
1680 		      net, net->ipv6.igmp_sk, skb, NULL, skb->dev,
1681 		      dst_output);
1682 out:
1683 	if (!err) {
1684 		ICMP6MSGOUT_INC_STATS(net, idev, ICMPV6_MLD2_REPORT);
1685 		ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
1686 	} else {
1687 		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
1688 	}
1689 
1690 	rcu_read_unlock();
1691 	return;
1692 
1693 err_out:
1694 	kfree_skb(skb);
1695 	goto out;
1696 }
1697 
1698 static int grec_size(struct ifmcaddr6 *pmc, int type, int gdel, int sdel)
1699 {
1700 	return sizeof(struct mld2_grec) + 16 * mld_scount(pmc,type,gdel,sdel);
1701 }
1702 
1703 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ifmcaddr6 *pmc,
1704 	int type, struct mld2_grec **ppgr, unsigned int mtu)
1705 {
1706 	struct mld2_report *pmr;
1707 	struct mld2_grec *pgr;
1708 
1709 	if (!skb) {
1710 		skb = mld_newpack(pmc->idev, mtu);
1711 		if (!skb)
1712 			return NULL;
1713 	}
1714 	pgr = skb_put(skb, sizeof(struct mld2_grec));
1715 	pgr->grec_type = type;
1716 	pgr->grec_auxwords = 0;
1717 	pgr->grec_nsrcs = 0;
1718 	pgr->grec_mca = pmc->mca_addr;	/* structure copy */
1719 	pmr = (struct mld2_report *)skb_transport_header(skb);
1720 	pmr->mld2r_ngrec = htons(ntohs(pmr->mld2r_ngrec)+1);
1721 	*ppgr = pgr;
1722 	return skb;
1723 }
1724 
1725 #define AVAILABLE(skb)	((skb) ? skb_availroom(skb) : 0)
1726 
1727 static struct sk_buff *add_grec(struct sk_buff *skb, struct ifmcaddr6 *pmc,
1728 	int type, int gdeleted, int sdeleted, int crsend)
1729 {
1730 	struct inet6_dev *idev = pmc->idev;
1731 	struct net_device *dev = idev->dev;
1732 	struct mld2_report *pmr;
1733 	struct mld2_grec *pgr = NULL;
1734 	struct ip6_sf_list *psf, *psf_next, *psf_prev, **psf_list;
1735 	int scount, stotal, first, isquery, truncate;
1736 	unsigned int mtu;
1737 
1738 	if (pmc->mca_flags & MAF_NOREPORT)
1739 		return skb;
1740 
1741 	mtu = READ_ONCE(dev->mtu);
1742 	if (mtu < IPV6_MIN_MTU)
1743 		return skb;
1744 
1745 	isquery = type == MLD2_MODE_IS_INCLUDE ||
1746 		  type == MLD2_MODE_IS_EXCLUDE;
1747 	truncate = type == MLD2_MODE_IS_EXCLUDE ||
1748 		    type == MLD2_CHANGE_TO_EXCLUDE;
1749 
1750 	stotal = scount = 0;
1751 
1752 	psf_list = sdeleted ? &pmc->mca_tomb : &pmc->mca_sources;
1753 
1754 	if (!*psf_list)
1755 		goto empty_source;
1756 
1757 	pmr = skb ? (struct mld2_report *)skb_transport_header(skb) : NULL;
1758 
1759 	/* EX and TO_EX get a fresh packet, if needed */
1760 	if (truncate) {
1761 		if (pmr && pmr->mld2r_ngrec &&
1762 		    AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
1763 			if (skb)
1764 				mld_sendpack(skb);
1765 			skb = mld_newpack(idev, mtu);
1766 		}
1767 	}
1768 	first = 1;
1769 	psf_prev = NULL;
1770 	for (psf = *psf_list; psf; psf = psf_next) {
1771 		struct in6_addr *psrc;
1772 
1773 		psf_next = psf->sf_next;
1774 
1775 		if (!is_in(pmc, psf, type, gdeleted, sdeleted) && !crsend) {
1776 			psf_prev = psf;
1777 			continue;
1778 		}
1779 
1780 		/* Based on RFC3810 6.1. Should not send source-list change
1781 		 * records when there is a filter mode change.
1782 		 */
1783 		if (((gdeleted && pmc->mca_sfmode == MCAST_EXCLUDE) ||
1784 		     (!gdeleted && pmc->mca_crcount)) &&
1785 		    (type == MLD2_ALLOW_NEW_SOURCES ||
1786 		     type == MLD2_BLOCK_OLD_SOURCES) && psf->sf_crcount)
1787 			goto decrease_sf_crcount;
1788 
1789 		/* clear marks on query responses */
1790 		if (isquery)
1791 			psf->sf_gsresp = 0;
1792 
1793 		if (AVAILABLE(skb) < sizeof(*psrc) +
1794 		    first*sizeof(struct mld2_grec)) {
1795 			if (truncate && !first)
1796 				break;	 /* truncate these */
1797 			if (pgr)
1798 				pgr->grec_nsrcs = htons(scount);
1799 			if (skb)
1800 				mld_sendpack(skb);
1801 			skb = mld_newpack(idev, mtu);
1802 			first = 1;
1803 			scount = 0;
1804 		}
1805 		if (first) {
1806 			skb = add_grhead(skb, pmc, type, &pgr, mtu);
1807 			first = 0;
1808 		}
1809 		if (!skb)
1810 			return NULL;
1811 		psrc = skb_put(skb, sizeof(*psrc));
1812 		*psrc = psf->sf_addr;
1813 		scount++; stotal++;
1814 		if ((type == MLD2_ALLOW_NEW_SOURCES ||
1815 		     type == MLD2_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
1816 decrease_sf_crcount:
1817 			psf->sf_crcount--;
1818 			if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
1819 				if (psf_prev)
1820 					psf_prev->sf_next = psf->sf_next;
1821 				else
1822 					*psf_list = psf->sf_next;
1823 				kfree(psf);
1824 				continue;
1825 			}
1826 		}
1827 		psf_prev = psf;
1828 	}
1829 
1830 empty_source:
1831 	if (!stotal) {
1832 		if (type == MLD2_ALLOW_NEW_SOURCES ||
1833 		    type == MLD2_BLOCK_OLD_SOURCES)
1834 			return skb;
1835 		if (pmc->mca_crcount || isquery || crsend) {
1836 			/* make sure we have room for group header */
1837 			if (skb && AVAILABLE(skb) < sizeof(struct mld2_grec)) {
1838 				mld_sendpack(skb);
1839 				skb = NULL; /* add_grhead will get a new one */
1840 			}
1841 			skb = add_grhead(skb, pmc, type, &pgr, mtu);
1842 		}
1843 	}
1844 	if (pgr)
1845 		pgr->grec_nsrcs = htons(scount);
1846 
1847 	if (isquery)
1848 		pmc->mca_flags &= ~MAF_GSQUERY;	/* clear query state */
1849 	return skb;
1850 }
1851 
1852 static void mld_send_report(struct inet6_dev *idev, struct ifmcaddr6 *pmc)
1853 {
1854 	struct sk_buff *skb = NULL;
1855 	int type;
1856 
1857 	read_lock_bh(&idev->lock);
1858 	if (!pmc) {
1859 		for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
1860 			if (pmc->mca_flags & MAF_NOREPORT)
1861 				continue;
1862 			spin_lock_bh(&pmc->mca_lock);
1863 			if (pmc->mca_sfcount[MCAST_EXCLUDE])
1864 				type = MLD2_MODE_IS_EXCLUDE;
1865 			else
1866 				type = MLD2_MODE_IS_INCLUDE;
1867 			skb = add_grec(skb, pmc, type, 0, 0, 0);
1868 			spin_unlock_bh(&pmc->mca_lock);
1869 		}
1870 	} else {
1871 		spin_lock_bh(&pmc->mca_lock);
1872 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
1873 			type = MLD2_MODE_IS_EXCLUDE;
1874 		else
1875 			type = MLD2_MODE_IS_INCLUDE;
1876 		skb = add_grec(skb, pmc, type, 0, 0, 0);
1877 		spin_unlock_bh(&pmc->mca_lock);
1878 	}
1879 	read_unlock_bh(&idev->lock);
1880 	if (skb)
1881 		mld_sendpack(skb);
1882 }
1883 
1884 /*
1885  * remove zero-count source records from a source filter list
1886  */
1887 static void mld_clear_zeros(struct ip6_sf_list **ppsf)
1888 {
1889 	struct ip6_sf_list *psf_prev, *psf_next, *psf;
1890 
1891 	psf_prev = NULL;
1892 	for (psf = *ppsf; psf; psf = psf_next) {
1893 		psf_next = psf->sf_next;
1894 		if (psf->sf_crcount == 0) {
1895 			if (psf_prev)
1896 				psf_prev->sf_next = psf->sf_next;
1897 			else
1898 				*ppsf = psf->sf_next;
1899 			kfree(psf);
1900 		} else
1901 			psf_prev = psf;
1902 	}
1903 }
1904 
1905 static void mld_send_cr(struct inet6_dev *idev)
1906 {
1907 	struct ifmcaddr6 *pmc, *pmc_prev, *pmc_next;
1908 	struct sk_buff *skb = NULL;
1909 	int type, dtype;
1910 
1911 	read_lock_bh(&idev->lock);
1912 	spin_lock(&idev->mc_lock);
1913 
1914 	/* deleted MCA's */
1915 	pmc_prev = NULL;
1916 	for (pmc = idev->mc_tomb; pmc; pmc = pmc_next) {
1917 		pmc_next = pmc->next;
1918 		if (pmc->mca_sfmode == MCAST_INCLUDE) {
1919 			type = MLD2_BLOCK_OLD_SOURCES;
1920 			dtype = MLD2_BLOCK_OLD_SOURCES;
1921 			skb = add_grec(skb, pmc, type, 1, 0, 0);
1922 			skb = add_grec(skb, pmc, dtype, 1, 1, 0);
1923 		}
1924 		if (pmc->mca_crcount) {
1925 			if (pmc->mca_sfmode == MCAST_EXCLUDE) {
1926 				type = MLD2_CHANGE_TO_INCLUDE;
1927 				skb = add_grec(skb, pmc, type, 1, 0, 0);
1928 			}
1929 			pmc->mca_crcount--;
1930 			if (pmc->mca_crcount == 0) {
1931 				mld_clear_zeros(&pmc->mca_tomb);
1932 				mld_clear_zeros(&pmc->mca_sources);
1933 			}
1934 		}
1935 		if (pmc->mca_crcount == 0 && !pmc->mca_tomb &&
1936 		    !pmc->mca_sources) {
1937 			if (pmc_prev)
1938 				pmc_prev->next = pmc_next;
1939 			else
1940 				idev->mc_tomb = pmc_next;
1941 			in6_dev_put(pmc->idev);
1942 			kfree(pmc);
1943 		} else
1944 			pmc_prev = pmc;
1945 	}
1946 	spin_unlock(&idev->mc_lock);
1947 
1948 	/* change recs */
1949 	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
1950 		spin_lock_bh(&pmc->mca_lock);
1951 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
1952 			type = MLD2_BLOCK_OLD_SOURCES;
1953 			dtype = MLD2_ALLOW_NEW_SOURCES;
1954 		} else {
1955 			type = MLD2_ALLOW_NEW_SOURCES;
1956 			dtype = MLD2_BLOCK_OLD_SOURCES;
1957 		}
1958 		skb = add_grec(skb, pmc, type, 0, 0, 0);
1959 		skb = add_grec(skb, pmc, dtype, 0, 1, 0);	/* deleted sources */
1960 
1961 		/* filter mode changes */
1962 		if (pmc->mca_crcount) {
1963 			if (pmc->mca_sfmode == MCAST_EXCLUDE)
1964 				type = MLD2_CHANGE_TO_EXCLUDE;
1965 			else
1966 				type = MLD2_CHANGE_TO_INCLUDE;
1967 			skb = add_grec(skb, pmc, type, 0, 0, 0);
1968 			pmc->mca_crcount--;
1969 		}
1970 		spin_unlock_bh(&pmc->mca_lock);
1971 	}
1972 	read_unlock_bh(&idev->lock);
1973 	if (!skb)
1974 		return;
1975 	(void) mld_sendpack(skb);
1976 }
1977 
1978 static void igmp6_send(struct in6_addr *addr, struct net_device *dev, int type)
1979 {
1980 	struct net *net = dev_net(dev);
1981 	struct sock *sk = net->ipv6.igmp_sk;
1982 	struct inet6_dev *idev;
1983 	struct sk_buff *skb;
1984 	struct mld_msg *hdr;
1985 	const struct in6_addr *snd_addr, *saddr;
1986 	struct in6_addr addr_buf;
1987 	int hlen = LL_RESERVED_SPACE(dev);
1988 	int tlen = dev->needed_tailroom;
1989 	int err, len, payload_len, full_len;
1990 	u8 ra[8] = { IPPROTO_ICMPV6, 0,
1991 		     IPV6_TLV_ROUTERALERT, 2, 0, 0,
1992 		     IPV6_TLV_PADN, 0 };
1993 	struct flowi6 fl6;
1994 	struct dst_entry *dst;
1995 
1996 	if (type == ICMPV6_MGM_REDUCTION)
1997 		snd_addr = &in6addr_linklocal_allrouters;
1998 	else
1999 		snd_addr = addr;
2000 
2001 	len = sizeof(struct icmp6hdr) + sizeof(struct in6_addr);
2002 	payload_len = len + sizeof(ra);
2003 	full_len = sizeof(struct ipv6hdr) + payload_len;
2004 
2005 	rcu_read_lock();
2006 	IP6_UPD_PO_STATS(net, __in6_dev_get(dev),
2007 		      IPSTATS_MIB_OUT, full_len);
2008 	rcu_read_unlock();
2009 
2010 	skb = sock_alloc_send_skb(sk, hlen + tlen + full_len, 1, &err);
2011 
2012 	if (!skb) {
2013 		rcu_read_lock();
2014 		IP6_INC_STATS(net, __in6_dev_get(dev),
2015 			      IPSTATS_MIB_OUTDISCARDS);
2016 		rcu_read_unlock();
2017 		return;
2018 	}
2019 	skb->priority = TC_PRIO_CONTROL;
2020 	skb_reserve(skb, hlen);
2021 
2022 	if (ipv6_get_lladdr(dev, &addr_buf, IFA_F_TENTATIVE)) {
2023 		/* <draft-ietf-magma-mld-source-05.txt>:
2024 		 * use unspecified address as the source address
2025 		 * when a valid link-local address is not available.
2026 		 */
2027 		saddr = &in6addr_any;
2028 	} else
2029 		saddr = &addr_buf;
2030 
2031 	ip6_mc_hdr(sk, skb, dev, saddr, snd_addr, NEXTHDR_HOP, payload_len);
2032 
2033 	skb_put_data(skb, ra, sizeof(ra));
2034 
2035 	hdr = skb_put_zero(skb, sizeof(struct mld_msg));
2036 	hdr->mld_type = type;
2037 	hdr->mld_mca = *addr;
2038 
2039 	hdr->mld_cksum = csum_ipv6_magic(saddr, snd_addr, len,
2040 					 IPPROTO_ICMPV6,
2041 					 csum_partial(hdr, len, 0));
2042 
2043 	rcu_read_lock();
2044 	idev = __in6_dev_get(skb->dev);
2045 
2046 	icmpv6_flow_init(sk, &fl6, type,
2047 			 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
2048 			 skb->dev->ifindex);
2049 	dst = icmp6_dst_alloc(skb->dev, &fl6);
2050 	if (IS_ERR(dst)) {
2051 		err = PTR_ERR(dst);
2052 		goto err_out;
2053 	}
2054 
2055 	skb_dst_set(skb, dst);
2056 	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
2057 		      net, sk, skb, NULL, skb->dev,
2058 		      dst_output);
2059 out:
2060 	if (!err) {
2061 		ICMP6MSGOUT_INC_STATS(net, idev, type);
2062 		ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
2063 	} else
2064 		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
2065 
2066 	rcu_read_unlock();
2067 	return;
2068 
2069 err_out:
2070 	kfree_skb(skb);
2071 	goto out;
2072 }
2073 
2074 static void mld_send_initial_cr(struct inet6_dev *idev)
2075 {
2076 	struct sk_buff *skb;
2077 	struct ifmcaddr6 *pmc;
2078 	int type;
2079 
2080 	if (mld_in_v1_mode(idev))
2081 		return;
2082 
2083 	skb = NULL;
2084 	read_lock_bh(&idev->lock);
2085 	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
2086 		spin_lock_bh(&pmc->mca_lock);
2087 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
2088 			type = MLD2_CHANGE_TO_EXCLUDE;
2089 		else
2090 			type = MLD2_ALLOW_NEW_SOURCES;
2091 		skb = add_grec(skb, pmc, type, 0, 0, 1);
2092 		spin_unlock_bh(&pmc->mca_lock);
2093 	}
2094 	read_unlock_bh(&idev->lock);
2095 	if (skb)
2096 		mld_sendpack(skb);
2097 }
2098 
2099 void ipv6_mc_dad_complete(struct inet6_dev *idev)
2100 {
2101 	idev->mc_dad_count = idev->mc_qrv;
2102 	if (idev->mc_dad_count) {
2103 		mld_send_initial_cr(idev);
2104 		idev->mc_dad_count--;
2105 		if (idev->mc_dad_count)
2106 			mld_dad_start_timer(idev,
2107 					    unsolicited_report_interval(idev));
2108 	}
2109 }
2110 
2111 static void mld_dad_timer_expire(struct timer_list *t)
2112 {
2113 	struct inet6_dev *idev = from_timer(idev, t, mc_dad_timer);
2114 
2115 	mld_send_initial_cr(idev);
2116 	if (idev->mc_dad_count) {
2117 		idev->mc_dad_count--;
2118 		if (idev->mc_dad_count)
2119 			mld_dad_start_timer(idev,
2120 					    unsolicited_report_interval(idev));
2121 	}
2122 	in6_dev_put(idev);
2123 }
2124 
2125 static int ip6_mc_del1_src(struct ifmcaddr6 *pmc, int sfmode,
2126 	const struct in6_addr *psfsrc)
2127 {
2128 	struct ip6_sf_list *psf, *psf_prev;
2129 	int rv = 0;
2130 
2131 	psf_prev = NULL;
2132 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
2133 		if (ipv6_addr_equal(&psf->sf_addr, psfsrc))
2134 			break;
2135 		psf_prev = psf;
2136 	}
2137 	if (!psf || psf->sf_count[sfmode] == 0) {
2138 		/* source filter not found, or count wrong =>  bug */
2139 		return -ESRCH;
2140 	}
2141 	psf->sf_count[sfmode]--;
2142 	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
2143 		struct inet6_dev *idev = pmc->idev;
2144 
2145 		/* no more filters for this source */
2146 		if (psf_prev)
2147 			psf_prev->sf_next = psf->sf_next;
2148 		else
2149 			pmc->mca_sources = psf->sf_next;
2150 		if (psf->sf_oldin && !(pmc->mca_flags & MAF_NOREPORT) &&
2151 		    !mld_in_v1_mode(idev)) {
2152 			psf->sf_crcount = idev->mc_qrv;
2153 			psf->sf_next = pmc->mca_tomb;
2154 			pmc->mca_tomb = psf;
2155 			rv = 1;
2156 		} else
2157 			kfree(psf);
2158 	}
2159 	return rv;
2160 }
2161 
2162 static int ip6_mc_del_src(struct inet6_dev *idev, const struct in6_addr *pmca,
2163 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
2164 			  int delta)
2165 {
2166 	struct ifmcaddr6 *pmc;
2167 	int	changerec = 0;
2168 	int	i, err;
2169 
2170 	if (!idev)
2171 		return -ENODEV;
2172 	read_lock_bh(&idev->lock);
2173 	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
2174 		if (ipv6_addr_equal(pmca, &pmc->mca_addr))
2175 			break;
2176 	}
2177 	if (!pmc) {
2178 		/* MCA not found?? bug */
2179 		read_unlock_bh(&idev->lock);
2180 		return -ESRCH;
2181 	}
2182 	spin_lock_bh(&pmc->mca_lock);
2183 	sf_markstate(pmc);
2184 	if (!delta) {
2185 		if (!pmc->mca_sfcount[sfmode]) {
2186 			spin_unlock_bh(&pmc->mca_lock);
2187 			read_unlock_bh(&idev->lock);
2188 			return -EINVAL;
2189 		}
2190 		pmc->mca_sfcount[sfmode]--;
2191 	}
2192 	err = 0;
2193 	for (i = 0; i < sfcount; i++) {
2194 		int rv = ip6_mc_del1_src(pmc, sfmode, &psfsrc[i]);
2195 
2196 		changerec |= rv > 0;
2197 		if (!err && rv < 0)
2198 			err = rv;
2199 	}
2200 	if (pmc->mca_sfmode == MCAST_EXCLUDE &&
2201 	    pmc->mca_sfcount[MCAST_EXCLUDE] == 0 &&
2202 	    pmc->mca_sfcount[MCAST_INCLUDE]) {
2203 		struct ip6_sf_list *psf;
2204 
2205 		/* filter mode change */
2206 		pmc->mca_sfmode = MCAST_INCLUDE;
2207 		pmc->mca_crcount = idev->mc_qrv;
2208 		idev->mc_ifc_count = pmc->mca_crcount;
2209 		for (psf = pmc->mca_sources; psf; psf = psf->sf_next)
2210 			psf->sf_crcount = 0;
2211 		mld_ifc_event(pmc->idev);
2212 	} else if (sf_setstate(pmc) || changerec)
2213 		mld_ifc_event(pmc->idev);
2214 	spin_unlock_bh(&pmc->mca_lock);
2215 	read_unlock_bh(&idev->lock);
2216 	return err;
2217 }
2218 
2219 /*
2220  * Add multicast single-source filter to the interface list
2221  */
2222 static int ip6_mc_add1_src(struct ifmcaddr6 *pmc, int sfmode,
2223 	const struct in6_addr *psfsrc)
2224 {
2225 	struct ip6_sf_list *psf, *psf_prev;
2226 
2227 	psf_prev = NULL;
2228 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
2229 		if (ipv6_addr_equal(&psf->sf_addr, psfsrc))
2230 			break;
2231 		psf_prev = psf;
2232 	}
2233 	if (!psf) {
2234 		psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
2235 		if (!psf)
2236 			return -ENOBUFS;
2237 
2238 		psf->sf_addr = *psfsrc;
2239 		if (psf_prev) {
2240 			psf_prev->sf_next = psf;
2241 		} else
2242 			pmc->mca_sources = psf;
2243 	}
2244 	psf->sf_count[sfmode]++;
2245 	return 0;
2246 }
2247 
2248 static void sf_markstate(struct ifmcaddr6 *pmc)
2249 {
2250 	struct ip6_sf_list *psf;
2251 	int mca_xcount = pmc->mca_sfcount[MCAST_EXCLUDE];
2252 
2253 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next)
2254 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
2255 			psf->sf_oldin = mca_xcount ==
2256 				psf->sf_count[MCAST_EXCLUDE] &&
2257 				!psf->sf_count[MCAST_INCLUDE];
2258 		} else
2259 			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
2260 }
2261 
2262 static int sf_setstate(struct ifmcaddr6 *pmc)
2263 {
2264 	struct ip6_sf_list *psf, *dpsf;
2265 	int mca_xcount = pmc->mca_sfcount[MCAST_EXCLUDE];
2266 	int qrv = pmc->idev->mc_qrv;
2267 	int new_in, rv;
2268 
2269 	rv = 0;
2270 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
2271 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
2272 			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
2273 				!psf->sf_count[MCAST_INCLUDE];
2274 		} else
2275 			new_in = psf->sf_count[MCAST_INCLUDE] != 0;
2276 		if (new_in) {
2277 			if (!psf->sf_oldin) {
2278 				struct ip6_sf_list *prev = NULL;
2279 
2280 				for (dpsf = pmc->mca_tomb; dpsf;
2281 				     dpsf = dpsf->sf_next) {
2282 					if (ipv6_addr_equal(&dpsf->sf_addr,
2283 					    &psf->sf_addr))
2284 						break;
2285 					prev = dpsf;
2286 				}
2287 				if (dpsf) {
2288 					if (prev)
2289 						prev->sf_next = dpsf->sf_next;
2290 					else
2291 						pmc->mca_tomb = dpsf->sf_next;
2292 					kfree(dpsf);
2293 				}
2294 				psf->sf_crcount = qrv;
2295 				rv++;
2296 			}
2297 		} else if (psf->sf_oldin) {
2298 			psf->sf_crcount = 0;
2299 			/*
2300 			 * add or update "delete" records if an active filter
2301 			 * is now inactive
2302 			 */
2303 			for (dpsf = pmc->mca_tomb; dpsf; dpsf = dpsf->sf_next)
2304 				if (ipv6_addr_equal(&dpsf->sf_addr,
2305 				    &psf->sf_addr))
2306 					break;
2307 			if (!dpsf) {
2308 				dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC);
2309 				if (!dpsf)
2310 					continue;
2311 				*dpsf = *psf;
2312 				/* pmc->mca_lock held by callers */
2313 				dpsf->sf_next = pmc->mca_tomb;
2314 				pmc->mca_tomb = dpsf;
2315 			}
2316 			dpsf->sf_crcount = qrv;
2317 			rv++;
2318 		}
2319 	}
2320 	return rv;
2321 }
2322 
2323 /*
2324  * Add multicast source filter list to the interface list
2325  */
2326 static int ip6_mc_add_src(struct inet6_dev *idev, const struct in6_addr *pmca,
2327 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
2328 			  int delta)
2329 {
2330 	struct ifmcaddr6 *pmc;
2331 	int	isexclude;
2332 	int	i, err;
2333 
2334 	if (!idev)
2335 		return -ENODEV;
2336 	read_lock_bh(&idev->lock);
2337 	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
2338 		if (ipv6_addr_equal(pmca, &pmc->mca_addr))
2339 			break;
2340 	}
2341 	if (!pmc) {
2342 		/* MCA not found?? bug */
2343 		read_unlock_bh(&idev->lock);
2344 		return -ESRCH;
2345 	}
2346 	spin_lock_bh(&pmc->mca_lock);
2347 
2348 	sf_markstate(pmc);
2349 	isexclude = pmc->mca_sfmode == MCAST_EXCLUDE;
2350 	if (!delta)
2351 		pmc->mca_sfcount[sfmode]++;
2352 	err = 0;
2353 	for (i = 0; i < sfcount; i++) {
2354 		err = ip6_mc_add1_src(pmc, sfmode, &psfsrc[i]);
2355 		if (err)
2356 			break;
2357 	}
2358 	if (err) {
2359 		int j;
2360 
2361 		if (!delta)
2362 			pmc->mca_sfcount[sfmode]--;
2363 		for (j = 0; j < i; j++)
2364 			ip6_mc_del1_src(pmc, sfmode, &psfsrc[j]);
2365 	} else if (isexclude != (pmc->mca_sfcount[MCAST_EXCLUDE] != 0)) {
2366 		struct ip6_sf_list *psf;
2367 
2368 		/* filter mode change */
2369 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
2370 			pmc->mca_sfmode = MCAST_EXCLUDE;
2371 		else if (pmc->mca_sfcount[MCAST_INCLUDE])
2372 			pmc->mca_sfmode = MCAST_INCLUDE;
2373 		/* else no filters; keep old mode for reports */
2374 
2375 		pmc->mca_crcount = idev->mc_qrv;
2376 		idev->mc_ifc_count = pmc->mca_crcount;
2377 		for (psf = pmc->mca_sources; psf; psf = psf->sf_next)
2378 			psf->sf_crcount = 0;
2379 		mld_ifc_event(idev);
2380 	} else if (sf_setstate(pmc))
2381 		mld_ifc_event(idev);
2382 	spin_unlock_bh(&pmc->mca_lock);
2383 	read_unlock_bh(&idev->lock);
2384 	return err;
2385 }
2386 
2387 static void ip6_mc_clear_src(struct ifmcaddr6 *pmc)
2388 {
2389 	struct ip6_sf_list *psf, *nextpsf;
2390 
2391 	for (psf = pmc->mca_tomb; psf; psf = nextpsf) {
2392 		nextpsf = psf->sf_next;
2393 		kfree(psf);
2394 	}
2395 	pmc->mca_tomb = NULL;
2396 	for (psf = pmc->mca_sources; psf; psf = nextpsf) {
2397 		nextpsf = psf->sf_next;
2398 		kfree(psf);
2399 	}
2400 	pmc->mca_sources = NULL;
2401 	pmc->mca_sfmode = MCAST_EXCLUDE;
2402 	pmc->mca_sfcount[MCAST_INCLUDE] = 0;
2403 	pmc->mca_sfcount[MCAST_EXCLUDE] = 1;
2404 }
2405 
2406 
2407 static void igmp6_join_group(struct ifmcaddr6 *ma)
2408 {
2409 	unsigned long delay;
2410 
2411 	if (ma->mca_flags & MAF_NOREPORT)
2412 		return;
2413 
2414 	igmp6_send(&ma->mca_addr, ma->idev->dev, ICMPV6_MGM_REPORT);
2415 
2416 	delay = prandom_u32() % unsolicited_report_interval(ma->idev);
2417 
2418 	spin_lock_bh(&ma->mca_lock);
2419 	if (del_timer(&ma->mca_timer)) {
2420 		refcount_dec(&ma->mca_refcnt);
2421 		delay = ma->mca_timer.expires - jiffies;
2422 	}
2423 
2424 	if (!mod_timer(&ma->mca_timer, jiffies + delay))
2425 		refcount_inc(&ma->mca_refcnt);
2426 	ma->mca_flags |= MAF_TIMER_RUNNING | MAF_LAST_REPORTER;
2427 	spin_unlock_bh(&ma->mca_lock);
2428 }
2429 
2430 static int ip6_mc_leave_src(struct sock *sk, struct ipv6_mc_socklist *iml,
2431 			    struct inet6_dev *idev)
2432 {
2433 	int err;
2434 
2435 	write_lock_bh(&iml->sflock);
2436 	if (!iml->sflist) {
2437 		/* any-source empty exclude case */
2438 		err = ip6_mc_del_src(idev, &iml->addr, iml->sfmode, 0, NULL, 0);
2439 	} else {
2440 		err = ip6_mc_del_src(idev, &iml->addr, iml->sfmode,
2441 				iml->sflist->sl_count, iml->sflist->sl_addr, 0);
2442 		sock_kfree_s(sk, iml->sflist, IP6_SFLSIZE(iml->sflist->sl_max));
2443 		iml->sflist = NULL;
2444 	}
2445 	write_unlock_bh(&iml->sflock);
2446 	return err;
2447 }
2448 
2449 static void igmp6_leave_group(struct ifmcaddr6 *ma)
2450 {
2451 	if (mld_in_v1_mode(ma->idev)) {
2452 		if (ma->mca_flags & MAF_LAST_REPORTER)
2453 			igmp6_send(&ma->mca_addr, ma->idev->dev,
2454 				ICMPV6_MGM_REDUCTION);
2455 	} else {
2456 		mld_add_delrec(ma->idev, ma);
2457 		mld_ifc_event(ma->idev);
2458 	}
2459 }
2460 
2461 static void mld_gq_timer_expire(struct timer_list *t)
2462 {
2463 	struct inet6_dev *idev = from_timer(idev, t, mc_gq_timer);
2464 
2465 	idev->mc_gq_running = 0;
2466 	mld_send_report(idev, NULL);
2467 	in6_dev_put(idev);
2468 }
2469 
2470 static void mld_ifc_timer_expire(struct timer_list *t)
2471 {
2472 	struct inet6_dev *idev = from_timer(idev, t, mc_ifc_timer);
2473 
2474 	mld_send_cr(idev);
2475 	if (idev->mc_ifc_count) {
2476 		idev->mc_ifc_count--;
2477 		if (idev->mc_ifc_count)
2478 			mld_ifc_start_timer(idev,
2479 					    unsolicited_report_interval(idev));
2480 	}
2481 	in6_dev_put(idev);
2482 }
2483 
2484 static void mld_ifc_event(struct inet6_dev *idev)
2485 {
2486 	if (mld_in_v1_mode(idev))
2487 		return;
2488 	idev->mc_ifc_count = idev->mc_qrv;
2489 	mld_ifc_start_timer(idev, 1);
2490 }
2491 
2492 static void igmp6_timer_handler(struct timer_list *t)
2493 {
2494 	struct ifmcaddr6 *ma = from_timer(ma, t, mca_timer);
2495 
2496 	if (mld_in_v1_mode(ma->idev))
2497 		igmp6_send(&ma->mca_addr, ma->idev->dev, ICMPV6_MGM_REPORT);
2498 	else
2499 		mld_send_report(ma->idev, ma);
2500 
2501 	spin_lock(&ma->mca_lock);
2502 	ma->mca_flags |=  MAF_LAST_REPORTER;
2503 	ma->mca_flags &= ~MAF_TIMER_RUNNING;
2504 	spin_unlock(&ma->mca_lock);
2505 	ma_put(ma);
2506 }
2507 
2508 /* Device changing type */
2509 
2510 void ipv6_mc_unmap(struct inet6_dev *idev)
2511 {
2512 	struct ifmcaddr6 *i;
2513 
2514 	/* Install multicast list, except for all-nodes (already installed) */
2515 
2516 	read_lock_bh(&idev->lock);
2517 	for (i = idev->mc_list; i; i = i->next)
2518 		igmp6_group_dropped(i);
2519 	read_unlock_bh(&idev->lock);
2520 }
2521 
2522 void ipv6_mc_remap(struct inet6_dev *idev)
2523 {
2524 	ipv6_mc_up(idev);
2525 }
2526 
2527 /* Device going down */
2528 
2529 void ipv6_mc_down(struct inet6_dev *idev)
2530 {
2531 	struct ifmcaddr6 *i;
2532 
2533 	/* Withdraw multicast list */
2534 
2535 	read_lock_bh(&idev->lock);
2536 
2537 	for (i = idev->mc_list; i; i = i->next)
2538 		igmp6_group_dropped(i);
2539 
2540 	/* Should stop timer after group drop. or we will
2541 	 * start timer again in mld_ifc_event()
2542 	 */
2543 	mld_ifc_stop_timer(idev);
2544 	mld_gq_stop_timer(idev);
2545 	mld_dad_stop_timer(idev);
2546 	read_unlock_bh(&idev->lock);
2547 }
2548 
2549 static void ipv6_mc_reset(struct inet6_dev *idev)
2550 {
2551 	idev->mc_qrv = sysctl_mld_qrv;
2552 	idev->mc_qi = MLD_QI_DEFAULT;
2553 	idev->mc_qri = MLD_QRI_DEFAULT;
2554 	idev->mc_v1_seen = 0;
2555 	idev->mc_maxdelay = unsolicited_report_interval(idev);
2556 }
2557 
2558 /* Device going up */
2559 
2560 void ipv6_mc_up(struct inet6_dev *idev)
2561 {
2562 	struct ifmcaddr6 *i;
2563 
2564 	/* Install multicast list, except for all-nodes (already installed) */
2565 
2566 	read_lock_bh(&idev->lock);
2567 	ipv6_mc_reset(idev);
2568 	for (i = idev->mc_list; i; i = i->next) {
2569 		mld_del_delrec(idev, i);
2570 		igmp6_group_added(i);
2571 	}
2572 	read_unlock_bh(&idev->lock);
2573 }
2574 
2575 /* IPv6 device initialization. */
2576 
2577 void ipv6_mc_init_dev(struct inet6_dev *idev)
2578 {
2579 	write_lock_bh(&idev->lock);
2580 	spin_lock_init(&idev->mc_lock);
2581 	idev->mc_gq_running = 0;
2582 	timer_setup(&idev->mc_gq_timer, mld_gq_timer_expire, 0);
2583 	idev->mc_tomb = NULL;
2584 	idev->mc_ifc_count = 0;
2585 	timer_setup(&idev->mc_ifc_timer, mld_ifc_timer_expire, 0);
2586 	timer_setup(&idev->mc_dad_timer, mld_dad_timer_expire, 0);
2587 	ipv6_mc_reset(idev);
2588 	write_unlock_bh(&idev->lock);
2589 }
2590 
2591 /*
2592  *	Device is about to be destroyed: clean up.
2593  */
2594 
2595 void ipv6_mc_destroy_dev(struct inet6_dev *idev)
2596 {
2597 	struct ifmcaddr6 *i;
2598 
2599 	/* Deactivate timers */
2600 	ipv6_mc_down(idev);
2601 	mld_clear_delrec(idev);
2602 
2603 	/* Delete all-nodes address. */
2604 	/* We cannot call ipv6_dev_mc_dec() directly, our caller in
2605 	 * addrconf.c has NULL'd out dev->ip6_ptr so in6_dev_get() will
2606 	 * fail.
2607 	 */
2608 	__ipv6_dev_mc_dec(idev, &in6addr_linklocal_allnodes);
2609 
2610 	if (idev->cnf.forwarding)
2611 		__ipv6_dev_mc_dec(idev, &in6addr_linklocal_allrouters);
2612 
2613 	write_lock_bh(&idev->lock);
2614 	while ((i = idev->mc_list) != NULL) {
2615 		idev->mc_list = i->next;
2616 
2617 		write_unlock_bh(&idev->lock);
2618 		ma_put(i);
2619 		write_lock_bh(&idev->lock);
2620 	}
2621 	write_unlock_bh(&idev->lock);
2622 }
2623 
2624 static void ipv6_mc_rejoin_groups(struct inet6_dev *idev)
2625 {
2626 	struct ifmcaddr6 *pmc;
2627 
2628 	ASSERT_RTNL();
2629 
2630 	if (mld_in_v1_mode(idev)) {
2631 		read_lock_bh(&idev->lock);
2632 		for (pmc = idev->mc_list; pmc; pmc = pmc->next)
2633 			igmp6_join_group(pmc);
2634 		read_unlock_bh(&idev->lock);
2635 	} else
2636 		mld_send_report(idev, NULL);
2637 }
2638 
2639 static int ipv6_mc_netdev_event(struct notifier_block *this,
2640 				unsigned long event,
2641 				void *ptr)
2642 {
2643 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
2644 	struct inet6_dev *idev = __in6_dev_get(dev);
2645 
2646 	switch (event) {
2647 	case NETDEV_RESEND_IGMP:
2648 		if (idev)
2649 			ipv6_mc_rejoin_groups(idev);
2650 		break;
2651 	default:
2652 		break;
2653 	}
2654 
2655 	return NOTIFY_DONE;
2656 }
2657 
2658 static struct notifier_block igmp6_netdev_notifier = {
2659 	.notifier_call = ipv6_mc_netdev_event,
2660 };
2661 
2662 #ifdef CONFIG_PROC_FS
2663 struct igmp6_mc_iter_state {
2664 	struct seq_net_private p;
2665 	struct net_device *dev;
2666 	struct inet6_dev *idev;
2667 };
2668 
2669 #define igmp6_mc_seq_private(seq)	((struct igmp6_mc_iter_state *)(seq)->private)
2670 
2671 static inline struct ifmcaddr6 *igmp6_mc_get_first(struct seq_file *seq)
2672 {
2673 	struct ifmcaddr6 *im = NULL;
2674 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2675 	struct net *net = seq_file_net(seq);
2676 
2677 	state->idev = NULL;
2678 	for_each_netdev_rcu(net, state->dev) {
2679 		struct inet6_dev *idev;
2680 		idev = __in6_dev_get(state->dev);
2681 		if (!idev)
2682 			continue;
2683 		read_lock_bh(&idev->lock);
2684 		im = idev->mc_list;
2685 		if (im) {
2686 			state->idev = idev;
2687 			break;
2688 		}
2689 		read_unlock_bh(&idev->lock);
2690 	}
2691 	return im;
2692 }
2693 
2694 static struct ifmcaddr6 *igmp6_mc_get_next(struct seq_file *seq, struct ifmcaddr6 *im)
2695 {
2696 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2697 
2698 	im = im->next;
2699 	while (!im) {
2700 		if (likely(state->idev))
2701 			read_unlock_bh(&state->idev->lock);
2702 
2703 		state->dev = next_net_device_rcu(state->dev);
2704 		if (!state->dev) {
2705 			state->idev = NULL;
2706 			break;
2707 		}
2708 		state->idev = __in6_dev_get(state->dev);
2709 		if (!state->idev)
2710 			continue;
2711 		read_lock_bh(&state->idev->lock);
2712 		im = state->idev->mc_list;
2713 	}
2714 	return im;
2715 }
2716 
2717 static struct ifmcaddr6 *igmp6_mc_get_idx(struct seq_file *seq, loff_t pos)
2718 {
2719 	struct ifmcaddr6 *im = igmp6_mc_get_first(seq);
2720 	if (im)
2721 		while (pos && (im = igmp6_mc_get_next(seq, im)) != NULL)
2722 			--pos;
2723 	return pos ? NULL : im;
2724 }
2725 
2726 static void *igmp6_mc_seq_start(struct seq_file *seq, loff_t *pos)
2727 	__acquires(RCU)
2728 {
2729 	rcu_read_lock();
2730 	return igmp6_mc_get_idx(seq, *pos);
2731 }
2732 
2733 static void *igmp6_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2734 {
2735 	struct ifmcaddr6 *im = igmp6_mc_get_next(seq, v);
2736 
2737 	++*pos;
2738 	return im;
2739 }
2740 
2741 static void igmp6_mc_seq_stop(struct seq_file *seq, void *v)
2742 	__releases(RCU)
2743 {
2744 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2745 
2746 	if (likely(state->idev)) {
2747 		read_unlock_bh(&state->idev->lock);
2748 		state->idev = NULL;
2749 	}
2750 	state->dev = NULL;
2751 	rcu_read_unlock();
2752 }
2753 
2754 static int igmp6_mc_seq_show(struct seq_file *seq, void *v)
2755 {
2756 	struct ifmcaddr6 *im = (struct ifmcaddr6 *)v;
2757 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2758 
2759 	seq_printf(seq,
2760 		   "%-4d %-15s %pi6 %5d %08X %ld\n",
2761 		   state->dev->ifindex, state->dev->name,
2762 		   &im->mca_addr,
2763 		   im->mca_users, im->mca_flags,
2764 		   (im->mca_flags&MAF_TIMER_RUNNING) ?
2765 		   jiffies_to_clock_t(im->mca_timer.expires-jiffies) : 0);
2766 	return 0;
2767 }
2768 
2769 static const struct seq_operations igmp6_mc_seq_ops = {
2770 	.start	=	igmp6_mc_seq_start,
2771 	.next	=	igmp6_mc_seq_next,
2772 	.stop	=	igmp6_mc_seq_stop,
2773 	.show	=	igmp6_mc_seq_show,
2774 };
2775 
2776 struct igmp6_mcf_iter_state {
2777 	struct seq_net_private p;
2778 	struct net_device *dev;
2779 	struct inet6_dev *idev;
2780 	struct ifmcaddr6 *im;
2781 };
2782 
2783 #define igmp6_mcf_seq_private(seq)	((struct igmp6_mcf_iter_state *)(seq)->private)
2784 
2785 static inline struct ip6_sf_list *igmp6_mcf_get_first(struct seq_file *seq)
2786 {
2787 	struct ip6_sf_list *psf = NULL;
2788 	struct ifmcaddr6 *im = NULL;
2789 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
2790 	struct net *net = seq_file_net(seq);
2791 
2792 	state->idev = NULL;
2793 	state->im = NULL;
2794 	for_each_netdev_rcu(net, state->dev) {
2795 		struct inet6_dev *idev;
2796 		idev = __in6_dev_get(state->dev);
2797 		if (unlikely(idev == NULL))
2798 			continue;
2799 		read_lock_bh(&idev->lock);
2800 		im = idev->mc_list;
2801 		if (likely(im)) {
2802 			spin_lock_bh(&im->mca_lock);
2803 			psf = im->mca_sources;
2804 			if (likely(psf)) {
2805 				state->im = im;
2806 				state->idev = idev;
2807 				break;
2808 			}
2809 			spin_unlock_bh(&im->mca_lock);
2810 		}
2811 		read_unlock_bh(&idev->lock);
2812 	}
2813 	return psf;
2814 }
2815 
2816 static struct ip6_sf_list *igmp6_mcf_get_next(struct seq_file *seq, struct ip6_sf_list *psf)
2817 {
2818 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
2819 
2820 	psf = psf->sf_next;
2821 	while (!psf) {
2822 		spin_unlock_bh(&state->im->mca_lock);
2823 		state->im = state->im->next;
2824 		while (!state->im) {
2825 			if (likely(state->idev))
2826 				read_unlock_bh(&state->idev->lock);
2827 
2828 			state->dev = next_net_device_rcu(state->dev);
2829 			if (!state->dev) {
2830 				state->idev = NULL;
2831 				goto out;
2832 			}
2833 			state->idev = __in6_dev_get(state->dev);
2834 			if (!state->idev)
2835 				continue;
2836 			read_lock_bh(&state->idev->lock);
2837 			state->im = state->idev->mc_list;
2838 		}
2839 		if (!state->im)
2840 			break;
2841 		spin_lock_bh(&state->im->mca_lock);
2842 		psf = state->im->mca_sources;
2843 	}
2844 out:
2845 	return psf;
2846 }
2847 
2848 static struct ip6_sf_list *igmp6_mcf_get_idx(struct seq_file *seq, loff_t pos)
2849 {
2850 	struct ip6_sf_list *psf = igmp6_mcf_get_first(seq);
2851 	if (psf)
2852 		while (pos && (psf = igmp6_mcf_get_next(seq, psf)) != NULL)
2853 			--pos;
2854 	return pos ? NULL : psf;
2855 }
2856 
2857 static void *igmp6_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2858 	__acquires(RCU)
2859 {
2860 	rcu_read_lock();
2861 	return *pos ? igmp6_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2862 }
2863 
2864 static void *igmp6_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2865 {
2866 	struct ip6_sf_list *psf;
2867 	if (v == SEQ_START_TOKEN)
2868 		psf = igmp6_mcf_get_first(seq);
2869 	else
2870 		psf = igmp6_mcf_get_next(seq, v);
2871 	++*pos;
2872 	return psf;
2873 }
2874 
2875 static void igmp6_mcf_seq_stop(struct seq_file *seq, void *v)
2876 	__releases(RCU)
2877 {
2878 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
2879 	if (likely(state->im)) {
2880 		spin_unlock_bh(&state->im->mca_lock);
2881 		state->im = NULL;
2882 	}
2883 	if (likely(state->idev)) {
2884 		read_unlock_bh(&state->idev->lock);
2885 		state->idev = NULL;
2886 	}
2887 	state->dev = NULL;
2888 	rcu_read_unlock();
2889 }
2890 
2891 static int igmp6_mcf_seq_show(struct seq_file *seq, void *v)
2892 {
2893 	struct ip6_sf_list *psf = (struct ip6_sf_list *)v;
2894 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
2895 
2896 	if (v == SEQ_START_TOKEN) {
2897 		seq_puts(seq, "Idx Device                Multicast Address                   Source Address    INC    EXC\n");
2898 	} else {
2899 		seq_printf(seq,
2900 			   "%3d %6.6s %pi6 %pi6 %6lu %6lu\n",
2901 			   state->dev->ifindex, state->dev->name,
2902 			   &state->im->mca_addr,
2903 			   &psf->sf_addr,
2904 			   psf->sf_count[MCAST_INCLUDE],
2905 			   psf->sf_count[MCAST_EXCLUDE]);
2906 	}
2907 	return 0;
2908 }
2909 
2910 static const struct seq_operations igmp6_mcf_seq_ops = {
2911 	.start	=	igmp6_mcf_seq_start,
2912 	.next	=	igmp6_mcf_seq_next,
2913 	.stop	=	igmp6_mcf_seq_stop,
2914 	.show	=	igmp6_mcf_seq_show,
2915 };
2916 
2917 static int __net_init igmp6_proc_init(struct net *net)
2918 {
2919 	int err;
2920 
2921 	err = -ENOMEM;
2922 	if (!proc_create_net("igmp6", 0444, net->proc_net, &igmp6_mc_seq_ops,
2923 			sizeof(struct igmp6_mc_iter_state)))
2924 		goto out;
2925 	if (!proc_create_net("mcfilter6", 0444, net->proc_net,
2926 			&igmp6_mcf_seq_ops,
2927 			sizeof(struct igmp6_mcf_iter_state)))
2928 		goto out_proc_net_igmp6;
2929 
2930 	err = 0;
2931 out:
2932 	return err;
2933 
2934 out_proc_net_igmp6:
2935 	remove_proc_entry("igmp6", net->proc_net);
2936 	goto out;
2937 }
2938 
2939 static void __net_exit igmp6_proc_exit(struct net *net)
2940 {
2941 	remove_proc_entry("mcfilter6", net->proc_net);
2942 	remove_proc_entry("igmp6", net->proc_net);
2943 }
2944 #else
2945 static inline int igmp6_proc_init(struct net *net)
2946 {
2947 	return 0;
2948 }
2949 static inline void igmp6_proc_exit(struct net *net)
2950 {
2951 }
2952 #endif
2953 
2954 static int __net_init igmp6_net_init(struct net *net)
2955 {
2956 	int err;
2957 
2958 	err = inet_ctl_sock_create(&net->ipv6.igmp_sk, PF_INET6,
2959 				   SOCK_RAW, IPPROTO_ICMPV6, net);
2960 	if (err < 0) {
2961 		pr_err("Failed to initialize the IGMP6 control socket (err %d)\n",
2962 		       err);
2963 		goto out;
2964 	}
2965 
2966 	inet6_sk(net->ipv6.igmp_sk)->hop_limit = 1;
2967 
2968 	err = inet_ctl_sock_create(&net->ipv6.mc_autojoin_sk, PF_INET6,
2969 				   SOCK_RAW, IPPROTO_ICMPV6, net);
2970 	if (err < 0) {
2971 		pr_err("Failed to initialize the IGMP6 autojoin socket (err %d)\n",
2972 		       err);
2973 		goto out_sock_create;
2974 	}
2975 
2976 	err = igmp6_proc_init(net);
2977 	if (err)
2978 		goto out_sock_create_autojoin;
2979 
2980 	return 0;
2981 
2982 out_sock_create_autojoin:
2983 	inet_ctl_sock_destroy(net->ipv6.mc_autojoin_sk);
2984 out_sock_create:
2985 	inet_ctl_sock_destroy(net->ipv6.igmp_sk);
2986 out:
2987 	return err;
2988 }
2989 
2990 static void __net_exit igmp6_net_exit(struct net *net)
2991 {
2992 	inet_ctl_sock_destroy(net->ipv6.igmp_sk);
2993 	inet_ctl_sock_destroy(net->ipv6.mc_autojoin_sk);
2994 	igmp6_proc_exit(net);
2995 }
2996 
2997 static struct pernet_operations igmp6_net_ops = {
2998 	.init = igmp6_net_init,
2999 	.exit = igmp6_net_exit,
3000 };
3001 
3002 int __init igmp6_init(void)
3003 {
3004 	return register_pernet_subsys(&igmp6_net_ops);
3005 }
3006 
3007 int __init igmp6_late_init(void)
3008 {
3009 	return register_netdevice_notifier(&igmp6_netdev_notifier);
3010 }
3011 
3012 void igmp6_cleanup(void)
3013 {
3014 	unregister_pernet_subsys(&igmp6_net_ops);
3015 }
3016 
3017 void igmp6_late_cleanup(void)
3018 {
3019 	unregister_netdevice_notifier(&igmp6_netdev_notifier);
3020 }
3021