xref: /openbmc/linux/net/ipv6/mcast.c (revision 4f3db074)
1 /*
2  *	Multicast support for IPv6
3  *	Linux INET6 implementation
4  *
5  *	Authors:
6  *	Pedro Roque		<roque@di.fc.ul.pt>
7  *
8  *	Based on linux/ipv4/igmp.c and linux/ipv4/ip_sockglue.c
9  *
10  *	This program is free software; you can redistribute it and/or
11  *      modify it under the terms of the GNU General Public License
12  *      as published by the Free Software Foundation; either version
13  *      2 of the License, or (at your option) any later version.
14  */
15 
16 /* Changes:
17  *
18  *	yoshfuji	: fix format of router-alert option
19  *	YOSHIFUJI Hideaki @USAGI:
20  *		Fixed source address for MLD message based on
21  *		<draft-ietf-magma-mld-source-05.txt>.
22  *	YOSHIFUJI Hideaki @USAGI:
23  *		- Ignore Queries for invalid addresses.
24  *		- MLD for link-local addresses.
25  *	David L Stevens <dlstevens@us.ibm.com>:
26  *		- MLDv2 support
27  */
28 
29 #include <linux/module.h>
30 #include <linux/errno.h>
31 #include <linux/types.h>
32 #include <linux/string.h>
33 #include <linux/socket.h>
34 #include <linux/sockios.h>
35 #include <linux/jiffies.h>
36 #include <linux/times.h>
37 #include <linux/net.h>
38 #include <linux/in.h>
39 #include <linux/in6.h>
40 #include <linux/netdevice.h>
41 #include <linux/if_arp.h>
42 #include <linux/route.h>
43 #include <linux/init.h>
44 #include <linux/proc_fs.h>
45 #include <linux/seq_file.h>
46 #include <linux/slab.h>
47 #include <linux/pkt_sched.h>
48 #include <net/mld.h>
49 
50 #include <linux/netfilter.h>
51 #include <linux/netfilter_ipv6.h>
52 
53 #include <net/net_namespace.h>
54 #include <net/sock.h>
55 #include <net/snmp.h>
56 
57 #include <net/ipv6.h>
58 #include <net/protocol.h>
59 #include <net/if_inet6.h>
60 #include <net/ndisc.h>
61 #include <net/addrconf.h>
62 #include <net/ip6_route.h>
63 #include <net/inet_common.h>
64 
65 #include <net/ip6_checksum.h>
66 
67 /* Ensure that we have struct in6_addr aligned on 32bit word. */
68 static void *__mld2_query_bugs[] __attribute__((__unused__)) = {
69 	BUILD_BUG_ON_NULL(offsetof(struct mld2_query, mld2q_srcs) % 4),
70 	BUILD_BUG_ON_NULL(offsetof(struct mld2_report, mld2r_grec) % 4),
71 	BUILD_BUG_ON_NULL(offsetof(struct mld2_grec, grec_mca) % 4)
72 };
73 
74 static struct in6_addr mld2_all_mcr = MLD2_ALL_MCR_INIT;
75 
76 static void igmp6_join_group(struct ifmcaddr6 *ma);
77 static void igmp6_leave_group(struct ifmcaddr6 *ma);
78 static void igmp6_timer_handler(unsigned long data);
79 
80 static void mld_gq_timer_expire(unsigned long data);
81 static void mld_ifc_timer_expire(unsigned long data);
82 static void mld_ifc_event(struct inet6_dev *idev);
83 static void mld_add_delrec(struct inet6_dev *idev, struct ifmcaddr6 *pmc);
84 static void mld_del_delrec(struct inet6_dev *idev, const struct in6_addr *addr);
85 static void mld_clear_delrec(struct inet6_dev *idev);
86 static bool mld_in_v1_mode(const struct inet6_dev *idev);
87 static int sf_setstate(struct ifmcaddr6 *pmc);
88 static void sf_markstate(struct ifmcaddr6 *pmc);
89 static void ip6_mc_clear_src(struct ifmcaddr6 *pmc);
90 static int ip6_mc_del_src(struct inet6_dev *idev, const struct in6_addr *pmca,
91 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
92 			  int delta);
93 static int ip6_mc_add_src(struct inet6_dev *idev, const struct in6_addr *pmca,
94 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
95 			  int delta);
96 static int ip6_mc_leave_src(struct sock *sk, struct ipv6_mc_socklist *iml,
97 			    struct inet6_dev *idev);
98 
99 #define MLD_QRV_DEFAULT		2
100 /* RFC3810, 9.2. Query Interval */
101 #define MLD_QI_DEFAULT		(125 * HZ)
102 /* RFC3810, 9.3. Query Response Interval */
103 #define MLD_QRI_DEFAULT		(10 * HZ)
104 
105 /* RFC3810, 8.1 Query Version Distinctions */
106 #define MLD_V1_QUERY_LEN	24
107 #define MLD_V2_QUERY_LEN_MIN	28
108 
109 #define IPV6_MLD_MAX_MSF	64
110 
111 int sysctl_mld_max_msf __read_mostly = IPV6_MLD_MAX_MSF;
112 int sysctl_mld_qrv __read_mostly = MLD_QRV_DEFAULT;
113 
114 /*
115  *	socket join on multicast group
116  */
117 
118 #define for_each_pmc_rcu(np, pmc)				\
119 	for (pmc = rcu_dereference(np->ipv6_mc_list);		\
120 	     pmc != NULL;					\
121 	     pmc = rcu_dereference(pmc->next))
122 
123 static int unsolicited_report_interval(struct inet6_dev *idev)
124 {
125 	int iv;
126 
127 	if (mld_in_v1_mode(idev))
128 		iv = idev->cnf.mldv1_unsolicited_report_interval;
129 	else
130 		iv = idev->cnf.mldv2_unsolicited_report_interval;
131 
132 	return iv > 0 ? iv : 1;
133 }
134 
135 int ipv6_sock_mc_join(struct sock *sk, int ifindex, const struct in6_addr *addr)
136 {
137 	struct net_device *dev = NULL;
138 	struct ipv6_mc_socklist *mc_lst;
139 	struct ipv6_pinfo *np = inet6_sk(sk);
140 	struct net *net = sock_net(sk);
141 	int err;
142 
143 	ASSERT_RTNL();
144 
145 	if (!ipv6_addr_is_multicast(addr))
146 		return -EINVAL;
147 
148 	rcu_read_lock();
149 	for_each_pmc_rcu(np, mc_lst) {
150 		if ((ifindex == 0 || mc_lst->ifindex == ifindex) &&
151 		    ipv6_addr_equal(&mc_lst->addr, addr)) {
152 			rcu_read_unlock();
153 			return -EADDRINUSE;
154 		}
155 	}
156 	rcu_read_unlock();
157 
158 	mc_lst = sock_kmalloc(sk, sizeof(struct ipv6_mc_socklist), GFP_KERNEL);
159 
160 	if (!mc_lst)
161 		return -ENOMEM;
162 
163 	mc_lst->next = NULL;
164 	mc_lst->addr = *addr;
165 
166 	if (ifindex == 0) {
167 		struct rt6_info *rt;
168 		rt = rt6_lookup(net, addr, NULL, 0, 0);
169 		if (rt) {
170 			dev = rt->dst.dev;
171 			ip6_rt_put(rt);
172 		}
173 	} else
174 		dev = __dev_get_by_index(net, ifindex);
175 
176 	if (!dev) {
177 		sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));
178 		return -ENODEV;
179 	}
180 
181 	mc_lst->ifindex = dev->ifindex;
182 	mc_lst->sfmode = MCAST_EXCLUDE;
183 	rwlock_init(&mc_lst->sflock);
184 	mc_lst->sflist = NULL;
185 
186 	/*
187 	 *	now add/increase the group membership on the device
188 	 */
189 
190 	err = ipv6_dev_mc_inc(dev, addr);
191 
192 	if (err) {
193 		sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));
194 		return err;
195 	}
196 
197 	mc_lst->next = np->ipv6_mc_list;
198 	rcu_assign_pointer(np->ipv6_mc_list, mc_lst);
199 
200 	return 0;
201 }
202 EXPORT_SYMBOL(ipv6_sock_mc_join);
203 
204 /*
205  *	socket leave on multicast group
206  */
207 int ipv6_sock_mc_drop(struct sock *sk, int ifindex, const struct in6_addr *addr)
208 {
209 	struct ipv6_pinfo *np = inet6_sk(sk);
210 	struct ipv6_mc_socklist *mc_lst;
211 	struct ipv6_mc_socklist __rcu **lnk;
212 	struct net *net = sock_net(sk);
213 
214 	ASSERT_RTNL();
215 
216 	if (!ipv6_addr_is_multicast(addr))
217 		return -EINVAL;
218 
219 	for (lnk = &np->ipv6_mc_list;
220 	     (mc_lst = rtnl_dereference(*lnk)) != NULL;
221 	      lnk = &mc_lst->next) {
222 		if ((ifindex == 0 || mc_lst->ifindex == ifindex) &&
223 		    ipv6_addr_equal(&mc_lst->addr, addr)) {
224 			struct net_device *dev;
225 
226 			*lnk = mc_lst->next;
227 
228 			dev = __dev_get_by_index(net, mc_lst->ifindex);
229 			if (dev) {
230 				struct inet6_dev *idev = __in6_dev_get(dev);
231 
232 				(void) ip6_mc_leave_src(sk, mc_lst, idev);
233 				if (idev)
234 					__ipv6_dev_mc_dec(idev, &mc_lst->addr);
235 			} else
236 				(void) ip6_mc_leave_src(sk, mc_lst, NULL);
237 
238 			atomic_sub(sizeof(*mc_lst), &sk->sk_omem_alloc);
239 			kfree_rcu(mc_lst, rcu);
240 			return 0;
241 		}
242 	}
243 
244 	return -EADDRNOTAVAIL;
245 }
246 EXPORT_SYMBOL(ipv6_sock_mc_drop);
247 
248 /* called with rcu_read_lock() */
249 static struct inet6_dev *ip6_mc_find_dev_rcu(struct net *net,
250 					     const struct in6_addr *group,
251 					     int ifindex)
252 {
253 	struct net_device *dev = NULL;
254 	struct inet6_dev *idev = NULL;
255 
256 	if (ifindex == 0) {
257 		struct rt6_info *rt = rt6_lookup(net, group, NULL, 0, 0);
258 
259 		if (rt) {
260 			dev = rt->dst.dev;
261 			ip6_rt_put(rt);
262 		}
263 	} else
264 		dev = dev_get_by_index_rcu(net, ifindex);
265 
266 	if (!dev)
267 		return NULL;
268 	idev = __in6_dev_get(dev);
269 	if (!idev)
270 		return NULL;
271 	read_lock_bh(&idev->lock);
272 	if (idev->dead) {
273 		read_unlock_bh(&idev->lock);
274 		return NULL;
275 	}
276 	return idev;
277 }
278 
279 void ipv6_sock_mc_close(struct sock *sk)
280 {
281 	struct ipv6_pinfo *np = inet6_sk(sk);
282 	struct ipv6_mc_socklist *mc_lst;
283 	struct net *net = sock_net(sk);
284 
285 	if (!rcu_access_pointer(np->ipv6_mc_list))
286 		return;
287 
288 	rtnl_lock();
289 	while ((mc_lst = rtnl_dereference(np->ipv6_mc_list)) != NULL) {
290 		struct net_device *dev;
291 
292 		np->ipv6_mc_list = mc_lst->next;
293 
294 		dev = __dev_get_by_index(net, mc_lst->ifindex);
295 		if (dev) {
296 			struct inet6_dev *idev = __in6_dev_get(dev);
297 
298 			(void) ip6_mc_leave_src(sk, mc_lst, idev);
299 			if (idev)
300 				__ipv6_dev_mc_dec(idev, &mc_lst->addr);
301 		} else
302 			(void) ip6_mc_leave_src(sk, mc_lst, NULL);
303 
304 		atomic_sub(sizeof(*mc_lst), &sk->sk_omem_alloc);
305 		kfree_rcu(mc_lst, rcu);
306 
307 	}
308 	rtnl_unlock();
309 }
310 
311 int ip6_mc_source(int add, int omode, struct sock *sk,
312 	struct group_source_req *pgsr)
313 {
314 	struct in6_addr *source, *group;
315 	struct ipv6_mc_socklist *pmc;
316 	struct inet6_dev *idev;
317 	struct ipv6_pinfo *inet6 = inet6_sk(sk);
318 	struct ip6_sf_socklist *psl;
319 	struct net *net = sock_net(sk);
320 	int i, j, rv;
321 	int leavegroup = 0;
322 	int pmclocked = 0;
323 	int err;
324 
325 	source = &((struct sockaddr_in6 *)&pgsr->gsr_source)->sin6_addr;
326 	group = &((struct sockaddr_in6 *)&pgsr->gsr_group)->sin6_addr;
327 
328 	if (!ipv6_addr_is_multicast(group))
329 		return -EINVAL;
330 
331 	rcu_read_lock();
332 	idev = ip6_mc_find_dev_rcu(net, group, pgsr->gsr_interface);
333 	if (!idev) {
334 		rcu_read_unlock();
335 		return -ENODEV;
336 	}
337 
338 	err = -EADDRNOTAVAIL;
339 
340 	for_each_pmc_rcu(inet6, pmc) {
341 		if (pgsr->gsr_interface && pmc->ifindex != pgsr->gsr_interface)
342 			continue;
343 		if (ipv6_addr_equal(&pmc->addr, group))
344 			break;
345 	}
346 	if (!pmc) {		/* must have a prior join */
347 		err = -EINVAL;
348 		goto done;
349 	}
350 	/* if a source filter was set, must be the same mode as before */
351 	if (pmc->sflist) {
352 		if (pmc->sfmode != omode) {
353 			err = -EINVAL;
354 			goto done;
355 		}
356 	} else if (pmc->sfmode != omode) {
357 		/* allow mode switches for empty-set filters */
358 		ip6_mc_add_src(idev, group, omode, 0, NULL, 0);
359 		ip6_mc_del_src(idev, group, pmc->sfmode, 0, NULL, 0);
360 		pmc->sfmode = omode;
361 	}
362 
363 	write_lock(&pmc->sflock);
364 	pmclocked = 1;
365 
366 	psl = pmc->sflist;
367 	if (!add) {
368 		if (!psl)
369 			goto done;	/* err = -EADDRNOTAVAIL */
370 		rv = !0;
371 		for (i = 0; i < psl->sl_count; i++) {
372 			rv = !ipv6_addr_equal(&psl->sl_addr[i], source);
373 			if (rv == 0)
374 				break;
375 		}
376 		if (rv)		/* source not found */
377 			goto done;	/* err = -EADDRNOTAVAIL */
378 
379 		/* special case - (INCLUDE, empty) == LEAVE_GROUP */
380 		if (psl->sl_count == 1 && omode == MCAST_INCLUDE) {
381 			leavegroup = 1;
382 			goto done;
383 		}
384 
385 		/* update the interface filter */
386 		ip6_mc_del_src(idev, group, omode, 1, source, 1);
387 
388 		for (j = i+1; j < psl->sl_count; j++)
389 			psl->sl_addr[j-1] = psl->sl_addr[j];
390 		psl->sl_count--;
391 		err = 0;
392 		goto done;
393 	}
394 	/* else, add a new source to the filter */
395 
396 	if (psl && psl->sl_count >= sysctl_mld_max_msf) {
397 		err = -ENOBUFS;
398 		goto done;
399 	}
400 	if (!psl || psl->sl_count == psl->sl_max) {
401 		struct ip6_sf_socklist *newpsl;
402 		int count = IP6_SFBLOCK;
403 
404 		if (psl)
405 			count += psl->sl_max;
406 		newpsl = sock_kmalloc(sk, IP6_SFLSIZE(count), GFP_ATOMIC);
407 		if (!newpsl) {
408 			err = -ENOBUFS;
409 			goto done;
410 		}
411 		newpsl->sl_max = count;
412 		newpsl->sl_count = count - IP6_SFBLOCK;
413 		if (psl) {
414 			for (i = 0; i < psl->sl_count; i++)
415 				newpsl->sl_addr[i] = psl->sl_addr[i];
416 			sock_kfree_s(sk, psl, IP6_SFLSIZE(psl->sl_max));
417 		}
418 		pmc->sflist = psl = newpsl;
419 	}
420 	rv = 1;	/* > 0 for insert logic below if sl_count is 0 */
421 	for (i = 0; i < psl->sl_count; i++) {
422 		rv = !ipv6_addr_equal(&psl->sl_addr[i], source);
423 		if (rv == 0) /* There is an error in the address. */
424 			goto done;
425 	}
426 	for (j = psl->sl_count-1; j >= i; j--)
427 		psl->sl_addr[j+1] = psl->sl_addr[j];
428 	psl->sl_addr[i] = *source;
429 	psl->sl_count++;
430 	err = 0;
431 	/* update the interface list */
432 	ip6_mc_add_src(idev, group, omode, 1, source, 1);
433 done:
434 	if (pmclocked)
435 		write_unlock(&pmc->sflock);
436 	read_unlock_bh(&idev->lock);
437 	rcu_read_unlock();
438 	if (leavegroup)
439 		err = ipv6_sock_mc_drop(sk, pgsr->gsr_interface, group);
440 	return err;
441 }
442 
443 int ip6_mc_msfilter(struct sock *sk, struct group_filter *gsf)
444 {
445 	const struct in6_addr *group;
446 	struct ipv6_mc_socklist *pmc;
447 	struct inet6_dev *idev;
448 	struct ipv6_pinfo *inet6 = inet6_sk(sk);
449 	struct ip6_sf_socklist *newpsl, *psl;
450 	struct net *net = sock_net(sk);
451 	int leavegroup = 0;
452 	int i, err;
453 
454 	group = &((struct sockaddr_in6 *)&gsf->gf_group)->sin6_addr;
455 
456 	if (!ipv6_addr_is_multicast(group))
457 		return -EINVAL;
458 	if (gsf->gf_fmode != MCAST_INCLUDE &&
459 	    gsf->gf_fmode != MCAST_EXCLUDE)
460 		return -EINVAL;
461 
462 	rcu_read_lock();
463 	idev = ip6_mc_find_dev_rcu(net, group, gsf->gf_interface);
464 
465 	if (!idev) {
466 		rcu_read_unlock();
467 		return -ENODEV;
468 	}
469 
470 	err = 0;
471 
472 	if (gsf->gf_fmode == MCAST_INCLUDE && gsf->gf_numsrc == 0) {
473 		leavegroup = 1;
474 		goto done;
475 	}
476 
477 	for_each_pmc_rcu(inet6, pmc) {
478 		if (pmc->ifindex != gsf->gf_interface)
479 			continue;
480 		if (ipv6_addr_equal(&pmc->addr, group))
481 			break;
482 	}
483 	if (!pmc) {		/* must have a prior join */
484 		err = -EINVAL;
485 		goto done;
486 	}
487 	if (gsf->gf_numsrc) {
488 		newpsl = sock_kmalloc(sk, IP6_SFLSIZE(gsf->gf_numsrc),
489 							  GFP_ATOMIC);
490 		if (!newpsl) {
491 			err = -ENOBUFS;
492 			goto done;
493 		}
494 		newpsl->sl_max = newpsl->sl_count = gsf->gf_numsrc;
495 		for (i = 0; i < newpsl->sl_count; ++i) {
496 			struct sockaddr_in6 *psin6;
497 
498 			psin6 = (struct sockaddr_in6 *)&gsf->gf_slist[i];
499 			newpsl->sl_addr[i] = psin6->sin6_addr;
500 		}
501 		err = ip6_mc_add_src(idev, group, gsf->gf_fmode,
502 			newpsl->sl_count, newpsl->sl_addr, 0);
503 		if (err) {
504 			sock_kfree_s(sk, newpsl, IP6_SFLSIZE(newpsl->sl_max));
505 			goto done;
506 		}
507 	} else {
508 		newpsl = NULL;
509 		(void) ip6_mc_add_src(idev, group, gsf->gf_fmode, 0, NULL, 0);
510 	}
511 
512 	write_lock(&pmc->sflock);
513 	psl = pmc->sflist;
514 	if (psl) {
515 		(void) ip6_mc_del_src(idev, group, pmc->sfmode,
516 			psl->sl_count, psl->sl_addr, 0);
517 		sock_kfree_s(sk, psl, IP6_SFLSIZE(psl->sl_max));
518 	} else
519 		(void) ip6_mc_del_src(idev, group, pmc->sfmode, 0, NULL, 0);
520 	pmc->sflist = newpsl;
521 	pmc->sfmode = gsf->gf_fmode;
522 	write_unlock(&pmc->sflock);
523 	err = 0;
524 done:
525 	read_unlock_bh(&idev->lock);
526 	rcu_read_unlock();
527 	if (leavegroup)
528 		err = ipv6_sock_mc_drop(sk, gsf->gf_interface, group);
529 	return err;
530 }
531 
532 int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf,
533 	struct group_filter __user *optval, int __user *optlen)
534 {
535 	int err, i, count, copycount;
536 	const struct in6_addr *group;
537 	struct ipv6_mc_socklist *pmc;
538 	struct inet6_dev *idev;
539 	struct ipv6_pinfo *inet6 = inet6_sk(sk);
540 	struct ip6_sf_socklist *psl;
541 	struct net *net = sock_net(sk);
542 
543 	group = &((struct sockaddr_in6 *)&gsf->gf_group)->sin6_addr;
544 
545 	if (!ipv6_addr_is_multicast(group))
546 		return -EINVAL;
547 
548 	rcu_read_lock();
549 	idev = ip6_mc_find_dev_rcu(net, group, gsf->gf_interface);
550 
551 	if (!idev) {
552 		rcu_read_unlock();
553 		return -ENODEV;
554 	}
555 
556 	err = -EADDRNOTAVAIL;
557 	/* changes to the ipv6_mc_list require the socket lock and
558 	 * rtnl lock. We have the socket lock and rcu read lock,
559 	 * so reading the list is safe.
560 	 */
561 
562 	for_each_pmc_rcu(inet6, pmc) {
563 		if (pmc->ifindex != gsf->gf_interface)
564 			continue;
565 		if (ipv6_addr_equal(group, &pmc->addr))
566 			break;
567 	}
568 	if (!pmc)		/* must have a prior join */
569 		goto done;
570 	gsf->gf_fmode = pmc->sfmode;
571 	psl = pmc->sflist;
572 	count = psl ? psl->sl_count : 0;
573 	read_unlock_bh(&idev->lock);
574 	rcu_read_unlock();
575 
576 	copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
577 	gsf->gf_numsrc = count;
578 	if (put_user(GROUP_FILTER_SIZE(copycount), optlen) ||
579 	    copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) {
580 		return -EFAULT;
581 	}
582 	/* changes to psl require the socket lock, and a write lock
583 	 * on pmc->sflock. We have the socket lock so reading here is safe.
584 	 */
585 	for (i = 0; i < copycount; i++) {
586 		struct sockaddr_in6 *psin6;
587 		struct sockaddr_storage ss;
588 
589 		psin6 = (struct sockaddr_in6 *)&ss;
590 		memset(&ss, 0, sizeof(ss));
591 		psin6->sin6_family = AF_INET6;
592 		psin6->sin6_addr = psl->sl_addr[i];
593 		if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss)))
594 			return -EFAULT;
595 	}
596 	return 0;
597 done:
598 	read_unlock_bh(&idev->lock);
599 	rcu_read_unlock();
600 	return err;
601 }
602 
603 bool inet6_mc_check(struct sock *sk, const struct in6_addr *mc_addr,
604 		    const struct in6_addr *src_addr)
605 {
606 	struct ipv6_pinfo *np = inet6_sk(sk);
607 	struct ipv6_mc_socklist *mc;
608 	struct ip6_sf_socklist *psl;
609 	bool rv = true;
610 
611 	rcu_read_lock();
612 	for_each_pmc_rcu(np, mc) {
613 		if (ipv6_addr_equal(&mc->addr, mc_addr))
614 			break;
615 	}
616 	if (!mc) {
617 		rcu_read_unlock();
618 		return true;
619 	}
620 	read_lock(&mc->sflock);
621 	psl = mc->sflist;
622 	if (!psl) {
623 		rv = mc->sfmode == MCAST_EXCLUDE;
624 	} else {
625 		int i;
626 
627 		for (i = 0; i < psl->sl_count; i++) {
628 			if (ipv6_addr_equal(&psl->sl_addr[i], src_addr))
629 				break;
630 		}
631 		if (mc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
632 			rv = false;
633 		if (mc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
634 			rv = false;
635 	}
636 	read_unlock(&mc->sflock);
637 	rcu_read_unlock();
638 
639 	return rv;
640 }
641 
642 static void igmp6_group_added(struct ifmcaddr6 *mc)
643 {
644 	struct net_device *dev = mc->idev->dev;
645 	char buf[MAX_ADDR_LEN];
646 
647 	if (IPV6_ADDR_MC_SCOPE(&mc->mca_addr) <
648 	    IPV6_ADDR_SCOPE_LINKLOCAL)
649 		return;
650 
651 	spin_lock_bh(&mc->mca_lock);
652 	if (!(mc->mca_flags&MAF_LOADED)) {
653 		mc->mca_flags |= MAF_LOADED;
654 		if (ndisc_mc_map(&mc->mca_addr, buf, dev, 0) == 0)
655 			dev_mc_add(dev, buf);
656 	}
657 	spin_unlock_bh(&mc->mca_lock);
658 
659 	if (!(dev->flags & IFF_UP) || (mc->mca_flags & MAF_NOREPORT))
660 		return;
661 
662 	if (mld_in_v1_mode(mc->idev)) {
663 		igmp6_join_group(mc);
664 		return;
665 	}
666 	/* else v2 */
667 
668 	mc->mca_crcount = mc->idev->mc_qrv;
669 	mld_ifc_event(mc->idev);
670 }
671 
672 static void igmp6_group_dropped(struct ifmcaddr6 *mc)
673 {
674 	struct net_device *dev = mc->idev->dev;
675 	char buf[MAX_ADDR_LEN];
676 
677 	if (IPV6_ADDR_MC_SCOPE(&mc->mca_addr) <
678 	    IPV6_ADDR_SCOPE_LINKLOCAL)
679 		return;
680 
681 	spin_lock_bh(&mc->mca_lock);
682 	if (mc->mca_flags&MAF_LOADED) {
683 		mc->mca_flags &= ~MAF_LOADED;
684 		if (ndisc_mc_map(&mc->mca_addr, buf, dev, 0) == 0)
685 			dev_mc_del(dev, buf);
686 	}
687 
688 	if (mc->mca_flags & MAF_NOREPORT)
689 		goto done;
690 	spin_unlock_bh(&mc->mca_lock);
691 
692 	if (!mc->idev->dead)
693 		igmp6_leave_group(mc);
694 
695 	spin_lock_bh(&mc->mca_lock);
696 	if (del_timer(&mc->mca_timer))
697 		atomic_dec(&mc->mca_refcnt);
698 done:
699 	ip6_mc_clear_src(mc);
700 	spin_unlock_bh(&mc->mca_lock);
701 }
702 
703 /*
704  * deleted ifmcaddr6 manipulation
705  */
706 static void mld_add_delrec(struct inet6_dev *idev, struct ifmcaddr6 *im)
707 {
708 	struct ifmcaddr6 *pmc;
709 
710 	/* this is an "ifmcaddr6" for convenience; only the fields below
711 	 * are actually used. In particular, the refcnt and users are not
712 	 * used for management of the delete list. Using the same structure
713 	 * for deleted items allows change reports to use common code with
714 	 * non-deleted or query-response MCA's.
715 	 */
716 	pmc = kzalloc(sizeof(*pmc), GFP_ATOMIC);
717 	if (!pmc)
718 		return;
719 
720 	spin_lock_bh(&im->mca_lock);
721 	spin_lock_init(&pmc->mca_lock);
722 	pmc->idev = im->idev;
723 	in6_dev_hold(idev);
724 	pmc->mca_addr = im->mca_addr;
725 	pmc->mca_crcount = idev->mc_qrv;
726 	pmc->mca_sfmode = im->mca_sfmode;
727 	if (pmc->mca_sfmode == MCAST_INCLUDE) {
728 		struct ip6_sf_list *psf;
729 
730 		pmc->mca_tomb = im->mca_tomb;
731 		pmc->mca_sources = im->mca_sources;
732 		im->mca_tomb = im->mca_sources = NULL;
733 		for (psf = pmc->mca_sources; psf; psf = psf->sf_next)
734 			psf->sf_crcount = pmc->mca_crcount;
735 	}
736 	spin_unlock_bh(&im->mca_lock);
737 
738 	spin_lock_bh(&idev->mc_lock);
739 	pmc->next = idev->mc_tomb;
740 	idev->mc_tomb = pmc;
741 	spin_unlock_bh(&idev->mc_lock);
742 }
743 
744 static void mld_del_delrec(struct inet6_dev *idev, const struct in6_addr *pmca)
745 {
746 	struct ifmcaddr6 *pmc, *pmc_prev;
747 	struct ip6_sf_list *psf, *psf_next;
748 
749 	spin_lock_bh(&idev->mc_lock);
750 	pmc_prev = NULL;
751 	for (pmc = idev->mc_tomb; pmc; pmc = pmc->next) {
752 		if (ipv6_addr_equal(&pmc->mca_addr, pmca))
753 			break;
754 		pmc_prev = pmc;
755 	}
756 	if (pmc) {
757 		if (pmc_prev)
758 			pmc_prev->next = pmc->next;
759 		else
760 			idev->mc_tomb = pmc->next;
761 	}
762 	spin_unlock_bh(&idev->mc_lock);
763 
764 	if (pmc) {
765 		for (psf = pmc->mca_tomb; psf; psf = psf_next) {
766 			psf_next = psf->sf_next;
767 			kfree(psf);
768 		}
769 		in6_dev_put(pmc->idev);
770 		kfree(pmc);
771 	}
772 }
773 
774 static void mld_clear_delrec(struct inet6_dev *idev)
775 {
776 	struct ifmcaddr6 *pmc, *nextpmc;
777 
778 	spin_lock_bh(&idev->mc_lock);
779 	pmc = idev->mc_tomb;
780 	idev->mc_tomb = NULL;
781 	spin_unlock_bh(&idev->mc_lock);
782 
783 	for (; pmc; pmc = nextpmc) {
784 		nextpmc = pmc->next;
785 		ip6_mc_clear_src(pmc);
786 		in6_dev_put(pmc->idev);
787 		kfree(pmc);
788 	}
789 
790 	/* clear dead sources, too */
791 	read_lock_bh(&idev->lock);
792 	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
793 		struct ip6_sf_list *psf, *psf_next;
794 
795 		spin_lock_bh(&pmc->mca_lock);
796 		psf = pmc->mca_tomb;
797 		pmc->mca_tomb = NULL;
798 		spin_unlock_bh(&pmc->mca_lock);
799 		for (; psf; psf = psf_next) {
800 			psf_next = psf->sf_next;
801 			kfree(psf);
802 		}
803 	}
804 	read_unlock_bh(&idev->lock);
805 }
806 
807 static void mca_get(struct ifmcaddr6 *mc)
808 {
809 	atomic_inc(&mc->mca_refcnt);
810 }
811 
812 static void ma_put(struct ifmcaddr6 *mc)
813 {
814 	if (atomic_dec_and_test(&mc->mca_refcnt)) {
815 		in6_dev_put(mc->idev);
816 		kfree(mc);
817 	}
818 }
819 
820 static struct ifmcaddr6 *mca_alloc(struct inet6_dev *idev,
821 				   const struct in6_addr *addr)
822 {
823 	struct ifmcaddr6 *mc;
824 
825 	mc = kzalloc(sizeof(*mc), GFP_ATOMIC);
826 	if (!mc)
827 		return NULL;
828 
829 	setup_timer(&mc->mca_timer, igmp6_timer_handler, (unsigned long)mc);
830 
831 	mc->mca_addr = *addr;
832 	mc->idev = idev; /* reference taken by caller */
833 	mc->mca_users = 1;
834 	/* mca_stamp should be updated upon changes */
835 	mc->mca_cstamp = mc->mca_tstamp = jiffies;
836 	atomic_set(&mc->mca_refcnt, 1);
837 	spin_lock_init(&mc->mca_lock);
838 
839 	/* initial mode is (EX, empty) */
840 	mc->mca_sfmode = MCAST_EXCLUDE;
841 	mc->mca_sfcount[MCAST_EXCLUDE] = 1;
842 
843 	if (ipv6_addr_is_ll_all_nodes(&mc->mca_addr) ||
844 	    IPV6_ADDR_MC_SCOPE(&mc->mca_addr) < IPV6_ADDR_SCOPE_LINKLOCAL)
845 		mc->mca_flags |= MAF_NOREPORT;
846 
847 	return mc;
848 }
849 
850 /*
851  *	device multicast group inc (add if not found)
852  */
853 int ipv6_dev_mc_inc(struct net_device *dev, const struct in6_addr *addr)
854 {
855 	struct ifmcaddr6 *mc;
856 	struct inet6_dev *idev;
857 
858 	ASSERT_RTNL();
859 
860 	/* we need to take a reference on idev */
861 	idev = in6_dev_get(dev);
862 
863 	if (!idev)
864 		return -EINVAL;
865 
866 	write_lock_bh(&idev->lock);
867 	if (idev->dead) {
868 		write_unlock_bh(&idev->lock);
869 		in6_dev_put(idev);
870 		return -ENODEV;
871 	}
872 
873 	for (mc = idev->mc_list; mc; mc = mc->next) {
874 		if (ipv6_addr_equal(&mc->mca_addr, addr)) {
875 			mc->mca_users++;
876 			write_unlock_bh(&idev->lock);
877 			ip6_mc_add_src(idev, &mc->mca_addr, MCAST_EXCLUDE, 0,
878 				NULL, 0);
879 			in6_dev_put(idev);
880 			return 0;
881 		}
882 	}
883 
884 	mc = mca_alloc(idev, addr);
885 	if (!mc) {
886 		write_unlock_bh(&idev->lock);
887 		in6_dev_put(idev);
888 		return -ENOMEM;
889 	}
890 
891 	mc->next = idev->mc_list;
892 	idev->mc_list = mc;
893 
894 	/* Hold this for the code below before we unlock,
895 	 * it is already exposed via idev->mc_list.
896 	 */
897 	mca_get(mc);
898 	write_unlock_bh(&idev->lock);
899 
900 	mld_del_delrec(idev, &mc->mca_addr);
901 	igmp6_group_added(mc);
902 	ma_put(mc);
903 	return 0;
904 }
905 
906 /*
907  *	device multicast group del
908  */
909 int __ipv6_dev_mc_dec(struct inet6_dev *idev, const struct in6_addr *addr)
910 {
911 	struct ifmcaddr6 *ma, **map;
912 
913 	ASSERT_RTNL();
914 
915 	write_lock_bh(&idev->lock);
916 	for (map = &idev->mc_list; (ma = *map) != NULL; map = &ma->next) {
917 		if (ipv6_addr_equal(&ma->mca_addr, addr)) {
918 			if (--ma->mca_users == 0) {
919 				*map = ma->next;
920 				write_unlock_bh(&idev->lock);
921 
922 				igmp6_group_dropped(ma);
923 
924 				ma_put(ma);
925 				return 0;
926 			}
927 			write_unlock_bh(&idev->lock);
928 			return 0;
929 		}
930 	}
931 	write_unlock_bh(&idev->lock);
932 
933 	return -ENOENT;
934 }
935 
936 int ipv6_dev_mc_dec(struct net_device *dev, const struct in6_addr *addr)
937 {
938 	struct inet6_dev *idev;
939 	int err;
940 
941 	ASSERT_RTNL();
942 
943 	idev = __in6_dev_get(dev);
944 	if (!idev)
945 		err = -ENODEV;
946 	else
947 		err = __ipv6_dev_mc_dec(idev, addr);
948 
949 	return err;
950 }
951 
952 /*
953  *	check if the interface/address pair is valid
954  */
955 bool ipv6_chk_mcast_addr(struct net_device *dev, const struct in6_addr *group,
956 			 const struct in6_addr *src_addr)
957 {
958 	struct inet6_dev *idev;
959 	struct ifmcaddr6 *mc;
960 	bool rv = false;
961 
962 	rcu_read_lock();
963 	idev = __in6_dev_get(dev);
964 	if (idev) {
965 		read_lock_bh(&idev->lock);
966 		for (mc = idev->mc_list; mc; mc = mc->next) {
967 			if (ipv6_addr_equal(&mc->mca_addr, group))
968 				break;
969 		}
970 		if (mc) {
971 			if (src_addr && !ipv6_addr_any(src_addr)) {
972 				struct ip6_sf_list *psf;
973 
974 				spin_lock_bh(&mc->mca_lock);
975 				for (psf = mc->mca_sources; psf; psf = psf->sf_next) {
976 					if (ipv6_addr_equal(&psf->sf_addr, src_addr))
977 						break;
978 				}
979 				if (psf)
980 					rv = psf->sf_count[MCAST_INCLUDE] ||
981 						psf->sf_count[MCAST_EXCLUDE] !=
982 						mc->mca_sfcount[MCAST_EXCLUDE];
983 				else
984 					rv = mc->mca_sfcount[MCAST_EXCLUDE] != 0;
985 				spin_unlock_bh(&mc->mca_lock);
986 			} else
987 				rv = true; /* don't filter unspecified source */
988 		}
989 		read_unlock_bh(&idev->lock);
990 	}
991 	rcu_read_unlock();
992 	return rv;
993 }
994 
995 static void mld_gq_start_timer(struct inet6_dev *idev)
996 {
997 	unsigned long tv = prandom_u32() % idev->mc_maxdelay;
998 
999 	idev->mc_gq_running = 1;
1000 	if (!mod_timer(&idev->mc_gq_timer, jiffies+tv+2))
1001 		in6_dev_hold(idev);
1002 }
1003 
1004 static void mld_gq_stop_timer(struct inet6_dev *idev)
1005 {
1006 	idev->mc_gq_running = 0;
1007 	if (del_timer(&idev->mc_gq_timer))
1008 		__in6_dev_put(idev);
1009 }
1010 
1011 static void mld_ifc_start_timer(struct inet6_dev *idev, unsigned long delay)
1012 {
1013 	unsigned long tv = prandom_u32() % delay;
1014 
1015 	if (!mod_timer(&idev->mc_ifc_timer, jiffies+tv+2))
1016 		in6_dev_hold(idev);
1017 }
1018 
1019 static void mld_ifc_stop_timer(struct inet6_dev *idev)
1020 {
1021 	idev->mc_ifc_count = 0;
1022 	if (del_timer(&idev->mc_ifc_timer))
1023 		__in6_dev_put(idev);
1024 }
1025 
1026 static void mld_dad_start_timer(struct inet6_dev *idev, unsigned long delay)
1027 {
1028 	unsigned long tv = prandom_u32() % delay;
1029 
1030 	if (!mod_timer(&idev->mc_dad_timer, jiffies+tv+2))
1031 		in6_dev_hold(idev);
1032 }
1033 
1034 static void mld_dad_stop_timer(struct inet6_dev *idev)
1035 {
1036 	if (del_timer(&idev->mc_dad_timer))
1037 		__in6_dev_put(idev);
1038 }
1039 
1040 /*
1041  *	IGMP handling (alias multicast ICMPv6 messages)
1042  */
1043 
1044 static void igmp6_group_queried(struct ifmcaddr6 *ma, unsigned long resptime)
1045 {
1046 	unsigned long delay = resptime;
1047 
1048 	/* Do not start timer for these addresses */
1049 	if (ipv6_addr_is_ll_all_nodes(&ma->mca_addr) ||
1050 	    IPV6_ADDR_MC_SCOPE(&ma->mca_addr) < IPV6_ADDR_SCOPE_LINKLOCAL)
1051 		return;
1052 
1053 	if (del_timer(&ma->mca_timer)) {
1054 		atomic_dec(&ma->mca_refcnt);
1055 		delay = ma->mca_timer.expires - jiffies;
1056 	}
1057 
1058 	if (delay >= resptime)
1059 		delay = prandom_u32() % resptime;
1060 
1061 	ma->mca_timer.expires = jiffies + delay;
1062 	if (!mod_timer(&ma->mca_timer, jiffies + delay))
1063 		atomic_inc(&ma->mca_refcnt);
1064 	ma->mca_flags |= MAF_TIMER_RUNNING;
1065 }
1066 
1067 /* mark EXCLUDE-mode sources */
1068 static bool mld_xmarksources(struct ifmcaddr6 *pmc, int nsrcs,
1069 			     const struct in6_addr *srcs)
1070 {
1071 	struct ip6_sf_list *psf;
1072 	int i, scount;
1073 
1074 	scount = 0;
1075 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
1076 		if (scount == nsrcs)
1077 			break;
1078 		for (i = 0; i < nsrcs; i++) {
1079 			/* skip inactive filters */
1080 			if (psf->sf_count[MCAST_INCLUDE] ||
1081 			    pmc->mca_sfcount[MCAST_EXCLUDE] !=
1082 			    psf->sf_count[MCAST_EXCLUDE])
1083 				break;
1084 			if (ipv6_addr_equal(&srcs[i], &psf->sf_addr)) {
1085 				scount++;
1086 				break;
1087 			}
1088 		}
1089 	}
1090 	pmc->mca_flags &= ~MAF_GSQUERY;
1091 	if (scount == nsrcs)	/* all sources excluded */
1092 		return false;
1093 	return true;
1094 }
1095 
1096 static bool mld_marksources(struct ifmcaddr6 *pmc, int nsrcs,
1097 			    const struct in6_addr *srcs)
1098 {
1099 	struct ip6_sf_list *psf;
1100 	int i, scount;
1101 
1102 	if (pmc->mca_sfmode == MCAST_EXCLUDE)
1103 		return mld_xmarksources(pmc, nsrcs, srcs);
1104 
1105 	/* mark INCLUDE-mode sources */
1106 
1107 	scount = 0;
1108 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
1109 		if (scount == nsrcs)
1110 			break;
1111 		for (i = 0; i < nsrcs; i++) {
1112 			if (ipv6_addr_equal(&srcs[i], &psf->sf_addr)) {
1113 				psf->sf_gsresp = 1;
1114 				scount++;
1115 				break;
1116 			}
1117 		}
1118 	}
1119 	if (!scount) {
1120 		pmc->mca_flags &= ~MAF_GSQUERY;
1121 		return false;
1122 	}
1123 	pmc->mca_flags |= MAF_GSQUERY;
1124 	return true;
1125 }
1126 
1127 static int mld_force_mld_version(const struct inet6_dev *idev)
1128 {
1129 	/* Normally, both are 0 here. If enforcement to a particular is
1130 	 * being used, individual device enforcement will have a lower
1131 	 * precedence over 'all' device (.../conf/all/force_mld_version).
1132 	 */
1133 
1134 	if (dev_net(idev->dev)->ipv6.devconf_all->force_mld_version != 0)
1135 		return dev_net(idev->dev)->ipv6.devconf_all->force_mld_version;
1136 	else
1137 		return idev->cnf.force_mld_version;
1138 }
1139 
1140 static bool mld_in_v2_mode_only(const struct inet6_dev *idev)
1141 {
1142 	return mld_force_mld_version(idev) == 2;
1143 }
1144 
1145 static bool mld_in_v1_mode_only(const struct inet6_dev *idev)
1146 {
1147 	return mld_force_mld_version(idev) == 1;
1148 }
1149 
1150 static bool mld_in_v1_mode(const struct inet6_dev *idev)
1151 {
1152 	if (mld_in_v2_mode_only(idev))
1153 		return false;
1154 	if (mld_in_v1_mode_only(idev))
1155 		return true;
1156 	if (idev->mc_v1_seen && time_before(jiffies, idev->mc_v1_seen))
1157 		return true;
1158 
1159 	return false;
1160 }
1161 
1162 static void mld_set_v1_mode(struct inet6_dev *idev)
1163 {
1164 	/* RFC3810, relevant sections:
1165 	 *  - 9.1. Robustness Variable
1166 	 *  - 9.2. Query Interval
1167 	 *  - 9.3. Query Response Interval
1168 	 *  - 9.12. Older Version Querier Present Timeout
1169 	 */
1170 	unsigned long switchback;
1171 
1172 	switchback = (idev->mc_qrv * idev->mc_qi) + idev->mc_qri;
1173 
1174 	idev->mc_v1_seen = jiffies + switchback;
1175 }
1176 
1177 static void mld_update_qrv(struct inet6_dev *idev,
1178 			   const struct mld2_query *mlh2)
1179 {
1180 	/* RFC3810, relevant sections:
1181 	 *  - 5.1.8. QRV (Querier's Robustness Variable)
1182 	 *  - 9.1. Robustness Variable
1183 	 */
1184 
1185 	/* The value of the Robustness Variable MUST NOT be zero,
1186 	 * and SHOULD NOT be one. Catch this here if we ever run
1187 	 * into such a case in future.
1188 	 */
1189 	const int min_qrv = min(MLD_QRV_DEFAULT, sysctl_mld_qrv);
1190 	WARN_ON(idev->mc_qrv == 0);
1191 
1192 	if (mlh2->mld2q_qrv > 0)
1193 		idev->mc_qrv = mlh2->mld2q_qrv;
1194 
1195 	if (unlikely(idev->mc_qrv < min_qrv)) {
1196 		net_warn_ratelimited("IPv6: MLD: clamping QRV from %u to %u!\n",
1197 				     idev->mc_qrv, min_qrv);
1198 		idev->mc_qrv = min_qrv;
1199 	}
1200 }
1201 
1202 static void mld_update_qi(struct inet6_dev *idev,
1203 			  const struct mld2_query *mlh2)
1204 {
1205 	/* RFC3810, relevant sections:
1206 	 *  - 5.1.9. QQIC (Querier's Query Interval Code)
1207 	 *  - 9.2. Query Interval
1208 	 *  - 9.12. Older Version Querier Present Timeout
1209 	 *    (the [Query Interval] in the last Query received)
1210 	 */
1211 	unsigned long mc_qqi;
1212 
1213 	if (mlh2->mld2q_qqic < 128) {
1214 		mc_qqi = mlh2->mld2q_qqic;
1215 	} else {
1216 		unsigned long mc_man, mc_exp;
1217 
1218 		mc_exp = MLDV2_QQIC_EXP(mlh2->mld2q_qqic);
1219 		mc_man = MLDV2_QQIC_MAN(mlh2->mld2q_qqic);
1220 
1221 		mc_qqi = (mc_man | 0x10) << (mc_exp + 3);
1222 	}
1223 
1224 	idev->mc_qi = mc_qqi * HZ;
1225 }
1226 
1227 static void mld_update_qri(struct inet6_dev *idev,
1228 			   const struct mld2_query *mlh2)
1229 {
1230 	/* RFC3810, relevant sections:
1231 	 *  - 5.1.3. Maximum Response Code
1232 	 *  - 9.3. Query Response Interval
1233 	 */
1234 	idev->mc_qri = msecs_to_jiffies(mldv2_mrc(mlh2));
1235 }
1236 
1237 static int mld_process_v1(struct inet6_dev *idev, struct mld_msg *mld,
1238 			  unsigned long *max_delay, bool v1_query)
1239 {
1240 	unsigned long mldv1_md;
1241 
1242 	/* Ignore v1 queries */
1243 	if (mld_in_v2_mode_only(idev))
1244 		return -EINVAL;
1245 
1246 	mldv1_md = ntohs(mld->mld_maxdelay);
1247 
1248 	/* When in MLDv1 fallback and a MLDv2 router start-up being
1249 	 * unaware of current MLDv1 operation, the MRC == MRD mapping
1250 	 * only works when the exponential algorithm is not being
1251 	 * used (as MLDv1 is unaware of such things).
1252 	 *
1253 	 * According to the RFC author, the MLDv2 implementations
1254 	 * he's aware of all use a MRC < 32768 on start up queries.
1255 	 *
1256 	 * Thus, should we *ever* encounter something else larger
1257 	 * than that, just assume the maximum possible within our
1258 	 * reach.
1259 	 */
1260 	if (!v1_query)
1261 		mldv1_md = min(mldv1_md, MLDV1_MRD_MAX_COMPAT);
1262 
1263 	*max_delay = max(msecs_to_jiffies(mldv1_md), 1UL);
1264 
1265 	/* MLDv1 router present: we need to go into v1 mode *only*
1266 	 * when an MLDv1 query is received as per section 9.12. of
1267 	 * RFC3810! And we know from RFC2710 section 3.7 that MLDv1
1268 	 * queries MUST be of exactly 24 octets.
1269 	 */
1270 	if (v1_query)
1271 		mld_set_v1_mode(idev);
1272 
1273 	/* cancel MLDv2 report timer */
1274 	mld_gq_stop_timer(idev);
1275 	/* cancel the interface change timer */
1276 	mld_ifc_stop_timer(idev);
1277 	/* clear deleted report items */
1278 	mld_clear_delrec(idev);
1279 
1280 	return 0;
1281 }
1282 
1283 static int mld_process_v2(struct inet6_dev *idev, struct mld2_query *mld,
1284 			  unsigned long *max_delay)
1285 {
1286 	*max_delay = max(msecs_to_jiffies(mldv2_mrc(mld)), 1UL);
1287 
1288 	mld_update_qrv(idev, mld);
1289 	mld_update_qi(idev, mld);
1290 	mld_update_qri(idev, mld);
1291 
1292 	idev->mc_maxdelay = *max_delay;
1293 
1294 	return 0;
1295 }
1296 
1297 /* called with rcu_read_lock() */
1298 int igmp6_event_query(struct sk_buff *skb)
1299 {
1300 	struct mld2_query *mlh2 = NULL;
1301 	struct ifmcaddr6 *ma;
1302 	const struct in6_addr *group;
1303 	unsigned long max_delay;
1304 	struct inet6_dev *idev;
1305 	struct mld_msg *mld;
1306 	int group_type;
1307 	int mark = 0;
1308 	int len, err;
1309 
1310 	if (!pskb_may_pull(skb, sizeof(struct in6_addr)))
1311 		return -EINVAL;
1312 
1313 	/* compute payload length excluding extension headers */
1314 	len = ntohs(ipv6_hdr(skb)->payload_len) + sizeof(struct ipv6hdr);
1315 	len -= skb_network_header_len(skb);
1316 
1317 	/* RFC3810 6.2
1318 	 * Upon reception of an MLD message that contains a Query, the node
1319 	 * checks if the source address of the message is a valid link-local
1320 	 * address, if the Hop Limit is set to 1, and if the Router Alert
1321 	 * option is present in the Hop-By-Hop Options header of the IPv6
1322 	 * packet.  If any of these checks fails, the packet is dropped.
1323 	 */
1324 	if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL) ||
1325 	    ipv6_hdr(skb)->hop_limit != 1 ||
1326 	    !(IP6CB(skb)->flags & IP6SKB_ROUTERALERT) ||
1327 	    IP6CB(skb)->ra != htons(IPV6_OPT_ROUTERALERT_MLD))
1328 		return -EINVAL;
1329 
1330 	idev = __in6_dev_get(skb->dev);
1331 	if (!idev)
1332 		return 0;
1333 
1334 	mld = (struct mld_msg *)icmp6_hdr(skb);
1335 	group = &mld->mld_mca;
1336 	group_type = ipv6_addr_type(group);
1337 
1338 	if (group_type != IPV6_ADDR_ANY &&
1339 	    !(group_type&IPV6_ADDR_MULTICAST))
1340 		return -EINVAL;
1341 
1342 	if (len < MLD_V1_QUERY_LEN) {
1343 		return -EINVAL;
1344 	} else if (len == MLD_V1_QUERY_LEN || mld_in_v1_mode(idev)) {
1345 		err = mld_process_v1(idev, mld, &max_delay,
1346 				     len == MLD_V1_QUERY_LEN);
1347 		if (err < 0)
1348 			return err;
1349 	} else if (len >= MLD_V2_QUERY_LEN_MIN) {
1350 		int srcs_offset = sizeof(struct mld2_query) -
1351 				  sizeof(struct icmp6hdr);
1352 
1353 		if (!pskb_may_pull(skb, srcs_offset))
1354 			return -EINVAL;
1355 
1356 		mlh2 = (struct mld2_query *)skb_transport_header(skb);
1357 
1358 		err = mld_process_v2(idev, mlh2, &max_delay);
1359 		if (err < 0)
1360 			return err;
1361 
1362 		if (group_type == IPV6_ADDR_ANY) { /* general query */
1363 			if (mlh2->mld2q_nsrcs)
1364 				return -EINVAL; /* no sources allowed */
1365 
1366 			mld_gq_start_timer(idev);
1367 			return 0;
1368 		}
1369 		/* mark sources to include, if group & source-specific */
1370 		if (mlh2->mld2q_nsrcs != 0) {
1371 			if (!pskb_may_pull(skb, srcs_offset +
1372 			    ntohs(mlh2->mld2q_nsrcs) * sizeof(struct in6_addr)))
1373 				return -EINVAL;
1374 
1375 			mlh2 = (struct mld2_query *)skb_transport_header(skb);
1376 			mark = 1;
1377 		}
1378 	} else {
1379 		return -EINVAL;
1380 	}
1381 
1382 	read_lock_bh(&idev->lock);
1383 	if (group_type == IPV6_ADDR_ANY) {
1384 		for (ma = idev->mc_list; ma; ma = ma->next) {
1385 			spin_lock_bh(&ma->mca_lock);
1386 			igmp6_group_queried(ma, max_delay);
1387 			spin_unlock_bh(&ma->mca_lock);
1388 		}
1389 	} else {
1390 		for (ma = idev->mc_list; ma; ma = ma->next) {
1391 			if (!ipv6_addr_equal(group, &ma->mca_addr))
1392 				continue;
1393 			spin_lock_bh(&ma->mca_lock);
1394 			if (ma->mca_flags & MAF_TIMER_RUNNING) {
1395 				/* gsquery <- gsquery && mark */
1396 				if (!mark)
1397 					ma->mca_flags &= ~MAF_GSQUERY;
1398 			} else {
1399 				/* gsquery <- mark */
1400 				if (mark)
1401 					ma->mca_flags |= MAF_GSQUERY;
1402 				else
1403 					ma->mca_flags &= ~MAF_GSQUERY;
1404 			}
1405 			if (!(ma->mca_flags & MAF_GSQUERY) ||
1406 			    mld_marksources(ma, ntohs(mlh2->mld2q_nsrcs), mlh2->mld2q_srcs))
1407 				igmp6_group_queried(ma, max_delay);
1408 			spin_unlock_bh(&ma->mca_lock);
1409 			break;
1410 		}
1411 	}
1412 	read_unlock_bh(&idev->lock);
1413 
1414 	return 0;
1415 }
1416 
1417 /* called with rcu_read_lock() */
1418 int igmp6_event_report(struct sk_buff *skb)
1419 {
1420 	struct ifmcaddr6 *ma;
1421 	struct inet6_dev *idev;
1422 	struct mld_msg *mld;
1423 	int addr_type;
1424 
1425 	/* Our own report looped back. Ignore it. */
1426 	if (skb->pkt_type == PACKET_LOOPBACK)
1427 		return 0;
1428 
1429 	/* send our report if the MC router may not have heard this report */
1430 	if (skb->pkt_type != PACKET_MULTICAST &&
1431 	    skb->pkt_type != PACKET_BROADCAST)
1432 		return 0;
1433 
1434 	if (!pskb_may_pull(skb, sizeof(*mld) - sizeof(struct icmp6hdr)))
1435 		return -EINVAL;
1436 
1437 	mld = (struct mld_msg *)icmp6_hdr(skb);
1438 
1439 	/* Drop reports with not link local source */
1440 	addr_type = ipv6_addr_type(&ipv6_hdr(skb)->saddr);
1441 	if (addr_type != IPV6_ADDR_ANY &&
1442 	    !(addr_type&IPV6_ADDR_LINKLOCAL))
1443 		return -EINVAL;
1444 
1445 	idev = __in6_dev_get(skb->dev);
1446 	if (!idev)
1447 		return -ENODEV;
1448 
1449 	/*
1450 	 *	Cancel the timer for this group
1451 	 */
1452 
1453 	read_lock_bh(&idev->lock);
1454 	for (ma = idev->mc_list; ma; ma = ma->next) {
1455 		if (ipv6_addr_equal(&ma->mca_addr, &mld->mld_mca)) {
1456 			spin_lock(&ma->mca_lock);
1457 			if (del_timer(&ma->mca_timer))
1458 				atomic_dec(&ma->mca_refcnt);
1459 			ma->mca_flags &= ~(MAF_LAST_REPORTER|MAF_TIMER_RUNNING);
1460 			spin_unlock(&ma->mca_lock);
1461 			break;
1462 		}
1463 	}
1464 	read_unlock_bh(&idev->lock);
1465 	return 0;
1466 }
1467 
1468 static bool is_in(struct ifmcaddr6 *pmc, struct ip6_sf_list *psf, int type,
1469 		  int gdeleted, int sdeleted)
1470 {
1471 	switch (type) {
1472 	case MLD2_MODE_IS_INCLUDE:
1473 	case MLD2_MODE_IS_EXCLUDE:
1474 		if (gdeleted || sdeleted)
1475 			return false;
1476 		if (!((pmc->mca_flags & MAF_GSQUERY) && !psf->sf_gsresp)) {
1477 			if (pmc->mca_sfmode == MCAST_INCLUDE)
1478 				return true;
1479 			/* don't include if this source is excluded
1480 			 * in all filters
1481 			 */
1482 			if (psf->sf_count[MCAST_INCLUDE])
1483 				return type == MLD2_MODE_IS_INCLUDE;
1484 			return pmc->mca_sfcount[MCAST_EXCLUDE] ==
1485 				psf->sf_count[MCAST_EXCLUDE];
1486 		}
1487 		return false;
1488 	case MLD2_CHANGE_TO_INCLUDE:
1489 		if (gdeleted || sdeleted)
1490 			return false;
1491 		return psf->sf_count[MCAST_INCLUDE] != 0;
1492 	case MLD2_CHANGE_TO_EXCLUDE:
1493 		if (gdeleted || sdeleted)
1494 			return false;
1495 		if (pmc->mca_sfcount[MCAST_EXCLUDE] == 0 ||
1496 		    psf->sf_count[MCAST_INCLUDE])
1497 			return false;
1498 		return pmc->mca_sfcount[MCAST_EXCLUDE] ==
1499 			psf->sf_count[MCAST_EXCLUDE];
1500 	case MLD2_ALLOW_NEW_SOURCES:
1501 		if (gdeleted || !psf->sf_crcount)
1502 			return false;
1503 		return (pmc->mca_sfmode == MCAST_INCLUDE) ^ sdeleted;
1504 	case MLD2_BLOCK_OLD_SOURCES:
1505 		if (pmc->mca_sfmode == MCAST_INCLUDE)
1506 			return gdeleted || (psf->sf_crcount && sdeleted);
1507 		return psf->sf_crcount && !gdeleted && !sdeleted;
1508 	}
1509 	return false;
1510 }
1511 
1512 static int
1513 mld_scount(struct ifmcaddr6 *pmc, int type, int gdeleted, int sdeleted)
1514 {
1515 	struct ip6_sf_list *psf;
1516 	int scount = 0;
1517 
1518 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
1519 		if (!is_in(pmc, psf, type, gdeleted, sdeleted))
1520 			continue;
1521 		scount++;
1522 	}
1523 	return scount;
1524 }
1525 
1526 static void ip6_mc_hdr(struct sock *sk, struct sk_buff *skb,
1527 		       struct net_device *dev,
1528 		       const struct in6_addr *saddr,
1529 		       const struct in6_addr *daddr,
1530 		       int proto, int len)
1531 {
1532 	struct ipv6hdr *hdr;
1533 
1534 	skb->protocol = htons(ETH_P_IPV6);
1535 	skb->dev = dev;
1536 
1537 	skb_reset_network_header(skb);
1538 	skb_put(skb, sizeof(struct ipv6hdr));
1539 	hdr = ipv6_hdr(skb);
1540 
1541 	ip6_flow_hdr(hdr, 0, 0);
1542 
1543 	hdr->payload_len = htons(len);
1544 	hdr->nexthdr = proto;
1545 	hdr->hop_limit = inet6_sk(sk)->hop_limit;
1546 
1547 	hdr->saddr = *saddr;
1548 	hdr->daddr = *daddr;
1549 }
1550 
1551 static struct sk_buff *mld_newpack(struct inet6_dev *idev, unsigned int mtu)
1552 {
1553 	struct net_device *dev = idev->dev;
1554 	struct net *net = dev_net(dev);
1555 	struct sock *sk = net->ipv6.igmp_sk;
1556 	struct sk_buff *skb;
1557 	struct mld2_report *pmr;
1558 	struct in6_addr addr_buf;
1559 	const struct in6_addr *saddr;
1560 	int hlen = LL_RESERVED_SPACE(dev);
1561 	int tlen = dev->needed_tailroom;
1562 	unsigned int size = mtu + hlen + tlen;
1563 	int err;
1564 	u8 ra[8] = { IPPROTO_ICMPV6, 0,
1565 		     IPV6_TLV_ROUTERALERT, 2, 0, 0,
1566 		     IPV6_TLV_PADN, 0 };
1567 
1568 	/* we assume size > sizeof(ra) here */
1569 	/* limit our allocations to order-0 page */
1570 	size = min_t(int, size, SKB_MAX_ORDER(0, 0));
1571 	skb = sock_alloc_send_skb(sk, size, 1, &err);
1572 
1573 	if (!skb)
1574 		return NULL;
1575 
1576 	skb->priority = TC_PRIO_CONTROL;
1577 	skb->reserved_tailroom = skb_end_offset(skb) -
1578 				 min(mtu, skb_end_offset(skb));
1579 	skb_reserve(skb, hlen);
1580 
1581 	if (__ipv6_get_lladdr(idev, &addr_buf, IFA_F_TENTATIVE)) {
1582 		/* <draft-ietf-magma-mld-source-05.txt>:
1583 		 * use unspecified address as the source address
1584 		 * when a valid link-local address is not available.
1585 		 */
1586 		saddr = &in6addr_any;
1587 	} else
1588 		saddr = &addr_buf;
1589 
1590 	ip6_mc_hdr(sk, skb, dev, saddr, &mld2_all_mcr, NEXTHDR_HOP, 0);
1591 
1592 	memcpy(skb_put(skb, sizeof(ra)), ra, sizeof(ra));
1593 
1594 	skb_set_transport_header(skb, skb_tail_pointer(skb) - skb->data);
1595 	skb_put(skb, sizeof(*pmr));
1596 	pmr = (struct mld2_report *)skb_transport_header(skb);
1597 	pmr->mld2r_type = ICMPV6_MLD2_REPORT;
1598 	pmr->mld2r_resv1 = 0;
1599 	pmr->mld2r_cksum = 0;
1600 	pmr->mld2r_resv2 = 0;
1601 	pmr->mld2r_ngrec = 0;
1602 	return skb;
1603 }
1604 
1605 static void mld_sendpack(struct sk_buff *skb)
1606 {
1607 	struct ipv6hdr *pip6 = ipv6_hdr(skb);
1608 	struct mld2_report *pmr =
1609 			      (struct mld2_report *)skb_transport_header(skb);
1610 	int payload_len, mldlen;
1611 	struct inet6_dev *idev;
1612 	struct net *net = dev_net(skb->dev);
1613 	int err;
1614 	struct flowi6 fl6;
1615 	struct dst_entry *dst;
1616 
1617 	rcu_read_lock();
1618 	idev = __in6_dev_get(skb->dev);
1619 	IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len);
1620 
1621 	payload_len = (skb_tail_pointer(skb) - skb_network_header(skb)) -
1622 		sizeof(*pip6);
1623 	mldlen = skb_tail_pointer(skb) - skb_transport_header(skb);
1624 	pip6->payload_len = htons(payload_len);
1625 
1626 	pmr->mld2r_cksum = csum_ipv6_magic(&pip6->saddr, &pip6->daddr, mldlen,
1627 					   IPPROTO_ICMPV6,
1628 					   csum_partial(skb_transport_header(skb),
1629 							mldlen, 0));
1630 
1631 	icmpv6_flow_init(net->ipv6.igmp_sk, &fl6, ICMPV6_MLD2_REPORT,
1632 			 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
1633 			 skb->dev->ifindex);
1634 	dst = icmp6_dst_alloc(skb->dev, &fl6);
1635 
1636 	err = 0;
1637 	if (IS_ERR(dst)) {
1638 		err = PTR_ERR(dst);
1639 		dst = NULL;
1640 	}
1641 	skb_dst_set(skb, dst);
1642 	if (err)
1643 		goto err_out;
1644 
1645 	payload_len = skb->len;
1646 
1647 	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
1648 		      net->ipv6.igmp_sk, skb, NULL, skb->dev,
1649 		      dst_output_sk);
1650 out:
1651 	if (!err) {
1652 		ICMP6MSGOUT_INC_STATS(net, idev, ICMPV6_MLD2_REPORT);
1653 		ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
1654 		IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUTMCAST, payload_len);
1655 	} else {
1656 		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
1657 	}
1658 
1659 	rcu_read_unlock();
1660 	return;
1661 
1662 err_out:
1663 	kfree_skb(skb);
1664 	goto out;
1665 }
1666 
1667 static int grec_size(struct ifmcaddr6 *pmc, int type, int gdel, int sdel)
1668 {
1669 	return sizeof(struct mld2_grec) + 16 * mld_scount(pmc,type,gdel,sdel);
1670 }
1671 
1672 static struct sk_buff *add_grhead(struct sk_buff *skb, struct ifmcaddr6 *pmc,
1673 	int type, struct mld2_grec **ppgr)
1674 {
1675 	struct net_device *dev = pmc->idev->dev;
1676 	struct mld2_report *pmr;
1677 	struct mld2_grec *pgr;
1678 
1679 	if (!skb)
1680 		skb = mld_newpack(pmc->idev, dev->mtu);
1681 	if (!skb)
1682 		return NULL;
1683 	pgr = (struct mld2_grec *)skb_put(skb, sizeof(struct mld2_grec));
1684 	pgr->grec_type = type;
1685 	pgr->grec_auxwords = 0;
1686 	pgr->grec_nsrcs = 0;
1687 	pgr->grec_mca = pmc->mca_addr;	/* structure copy */
1688 	pmr = (struct mld2_report *)skb_transport_header(skb);
1689 	pmr->mld2r_ngrec = htons(ntohs(pmr->mld2r_ngrec)+1);
1690 	*ppgr = pgr;
1691 	return skb;
1692 }
1693 
1694 #define AVAILABLE(skb)	((skb) ? skb_availroom(skb) : 0)
1695 
1696 static struct sk_buff *add_grec(struct sk_buff *skb, struct ifmcaddr6 *pmc,
1697 	int type, int gdeleted, int sdeleted, int crsend)
1698 {
1699 	struct inet6_dev *idev = pmc->idev;
1700 	struct net_device *dev = idev->dev;
1701 	struct mld2_report *pmr;
1702 	struct mld2_grec *pgr = NULL;
1703 	struct ip6_sf_list *psf, *psf_next, *psf_prev, **psf_list;
1704 	int scount, stotal, first, isquery, truncate;
1705 
1706 	if (pmc->mca_flags & MAF_NOREPORT)
1707 		return skb;
1708 
1709 	isquery = type == MLD2_MODE_IS_INCLUDE ||
1710 		  type == MLD2_MODE_IS_EXCLUDE;
1711 	truncate = type == MLD2_MODE_IS_EXCLUDE ||
1712 		    type == MLD2_CHANGE_TO_EXCLUDE;
1713 
1714 	stotal = scount = 0;
1715 
1716 	psf_list = sdeleted ? &pmc->mca_tomb : &pmc->mca_sources;
1717 
1718 	if (!*psf_list)
1719 		goto empty_source;
1720 
1721 	pmr = skb ? (struct mld2_report *)skb_transport_header(skb) : NULL;
1722 
1723 	/* EX and TO_EX get a fresh packet, if needed */
1724 	if (truncate) {
1725 		if (pmr && pmr->mld2r_ngrec &&
1726 		    AVAILABLE(skb) < grec_size(pmc, type, gdeleted, sdeleted)) {
1727 			if (skb)
1728 				mld_sendpack(skb);
1729 			skb = mld_newpack(idev, dev->mtu);
1730 		}
1731 	}
1732 	first = 1;
1733 	psf_prev = NULL;
1734 	for (psf = *psf_list; psf; psf = psf_next) {
1735 		struct in6_addr *psrc;
1736 
1737 		psf_next = psf->sf_next;
1738 
1739 		if (!is_in(pmc, psf, type, gdeleted, sdeleted)) {
1740 			psf_prev = psf;
1741 			continue;
1742 		}
1743 
1744 		/* clear marks on query responses */
1745 		if (isquery)
1746 			psf->sf_gsresp = 0;
1747 
1748 		if (AVAILABLE(skb) < sizeof(*psrc) +
1749 		    first*sizeof(struct mld2_grec)) {
1750 			if (truncate && !first)
1751 				break;	 /* truncate these */
1752 			if (pgr)
1753 				pgr->grec_nsrcs = htons(scount);
1754 			if (skb)
1755 				mld_sendpack(skb);
1756 			skb = mld_newpack(idev, dev->mtu);
1757 			first = 1;
1758 			scount = 0;
1759 		}
1760 		if (first) {
1761 			skb = add_grhead(skb, pmc, type, &pgr);
1762 			first = 0;
1763 		}
1764 		if (!skb)
1765 			return NULL;
1766 		psrc = (struct in6_addr *)skb_put(skb, sizeof(*psrc));
1767 		*psrc = psf->sf_addr;
1768 		scount++; stotal++;
1769 		if ((type == MLD2_ALLOW_NEW_SOURCES ||
1770 		     type == MLD2_BLOCK_OLD_SOURCES) && psf->sf_crcount) {
1771 			psf->sf_crcount--;
1772 			if ((sdeleted || gdeleted) && psf->sf_crcount == 0) {
1773 				if (psf_prev)
1774 					psf_prev->sf_next = psf->sf_next;
1775 				else
1776 					*psf_list = psf->sf_next;
1777 				kfree(psf);
1778 				continue;
1779 			}
1780 		}
1781 		psf_prev = psf;
1782 	}
1783 
1784 empty_source:
1785 	if (!stotal) {
1786 		if (type == MLD2_ALLOW_NEW_SOURCES ||
1787 		    type == MLD2_BLOCK_OLD_SOURCES)
1788 			return skb;
1789 		if (pmc->mca_crcount || isquery || crsend) {
1790 			/* make sure we have room for group header */
1791 			if (skb && AVAILABLE(skb) < sizeof(struct mld2_grec)) {
1792 				mld_sendpack(skb);
1793 				skb = NULL; /* add_grhead will get a new one */
1794 			}
1795 			skb = add_grhead(skb, pmc, type, &pgr);
1796 		}
1797 	}
1798 	if (pgr)
1799 		pgr->grec_nsrcs = htons(scount);
1800 
1801 	if (isquery)
1802 		pmc->mca_flags &= ~MAF_GSQUERY;	/* clear query state */
1803 	return skb;
1804 }
1805 
1806 static void mld_send_report(struct inet6_dev *idev, struct ifmcaddr6 *pmc)
1807 {
1808 	struct sk_buff *skb = NULL;
1809 	int type;
1810 
1811 	read_lock_bh(&idev->lock);
1812 	if (!pmc) {
1813 		for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
1814 			if (pmc->mca_flags & MAF_NOREPORT)
1815 				continue;
1816 			spin_lock_bh(&pmc->mca_lock);
1817 			if (pmc->mca_sfcount[MCAST_EXCLUDE])
1818 				type = MLD2_MODE_IS_EXCLUDE;
1819 			else
1820 				type = MLD2_MODE_IS_INCLUDE;
1821 			skb = add_grec(skb, pmc, type, 0, 0, 0);
1822 			spin_unlock_bh(&pmc->mca_lock);
1823 		}
1824 	} else {
1825 		spin_lock_bh(&pmc->mca_lock);
1826 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
1827 			type = MLD2_MODE_IS_EXCLUDE;
1828 		else
1829 			type = MLD2_MODE_IS_INCLUDE;
1830 		skb = add_grec(skb, pmc, type, 0, 0, 0);
1831 		spin_unlock_bh(&pmc->mca_lock);
1832 	}
1833 	read_unlock_bh(&idev->lock);
1834 	if (skb)
1835 		mld_sendpack(skb);
1836 }
1837 
1838 /*
1839  * remove zero-count source records from a source filter list
1840  */
1841 static void mld_clear_zeros(struct ip6_sf_list **ppsf)
1842 {
1843 	struct ip6_sf_list *psf_prev, *psf_next, *psf;
1844 
1845 	psf_prev = NULL;
1846 	for (psf = *ppsf; psf; psf = psf_next) {
1847 		psf_next = psf->sf_next;
1848 		if (psf->sf_crcount == 0) {
1849 			if (psf_prev)
1850 				psf_prev->sf_next = psf->sf_next;
1851 			else
1852 				*ppsf = psf->sf_next;
1853 			kfree(psf);
1854 		} else
1855 			psf_prev = psf;
1856 	}
1857 }
1858 
1859 static void mld_send_cr(struct inet6_dev *idev)
1860 {
1861 	struct ifmcaddr6 *pmc, *pmc_prev, *pmc_next;
1862 	struct sk_buff *skb = NULL;
1863 	int type, dtype;
1864 
1865 	read_lock_bh(&idev->lock);
1866 	spin_lock(&idev->mc_lock);
1867 
1868 	/* deleted MCA's */
1869 	pmc_prev = NULL;
1870 	for (pmc = idev->mc_tomb; pmc; pmc = pmc_next) {
1871 		pmc_next = pmc->next;
1872 		if (pmc->mca_sfmode == MCAST_INCLUDE) {
1873 			type = MLD2_BLOCK_OLD_SOURCES;
1874 			dtype = MLD2_BLOCK_OLD_SOURCES;
1875 			skb = add_grec(skb, pmc, type, 1, 0, 0);
1876 			skb = add_grec(skb, pmc, dtype, 1, 1, 0);
1877 		}
1878 		if (pmc->mca_crcount) {
1879 			if (pmc->mca_sfmode == MCAST_EXCLUDE) {
1880 				type = MLD2_CHANGE_TO_INCLUDE;
1881 				skb = add_grec(skb, pmc, type, 1, 0, 0);
1882 			}
1883 			pmc->mca_crcount--;
1884 			if (pmc->mca_crcount == 0) {
1885 				mld_clear_zeros(&pmc->mca_tomb);
1886 				mld_clear_zeros(&pmc->mca_sources);
1887 			}
1888 		}
1889 		if (pmc->mca_crcount == 0 && !pmc->mca_tomb &&
1890 		    !pmc->mca_sources) {
1891 			if (pmc_prev)
1892 				pmc_prev->next = pmc_next;
1893 			else
1894 				idev->mc_tomb = pmc_next;
1895 			in6_dev_put(pmc->idev);
1896 			kfree(pmc);
1897 		} else
1898 			pmc_prev = pmc;
1899 	}
1900 	spin_unlock(&idev->mc_lock);
1901 
1902 	/* change recs */
1903 	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
1904 		spin_lock_bh(&pmc->mca_lock);
1905 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
1906 			type = MLD2_BLOCK_OLD_SOURCES;
1907 			dtype = MLD2_ALLOW_NEW_SOURCES;
1908 		} else {
1909 			type = MLD2_ALLOW_NEW_SOURCES;
1910 			dtype = MLD2_BLOCK_OLD_SOURCES;
1911 		}
1912 		skb = add_grec(skb, pmc, type, 0, 0, 0);
1913 		skb = add_grec(skb, pmc, dtype, 0, 1, 0);	/* deleted sources */
1914 
1915 		/* filter mode changes */
1916 		if (pmc->mca_crcount) {
1917 			if (pmc->mca_sfmode == MCAST_EXCLUDE)
1918 				type = MLD2_CHANGE_TO_EXCLUDE;
1919 			else
1920 				type = MLD2_CHANGE_TO_INCLUDE;
1921 			skb = add_grec(skb, pmc, type, 0, 0, 0);
1922 			pmc->mca_crcount--;
1923 		}
1924 		spin_unlock_bh(&pmc->mca_lock);
1925 	}
1926 	read_unlock_bh(&idev->lock);
1927 	if (!skb)
1928 		return;
1929 	(void) mld_sendpack(skb);
1930 }
1931 
1932 static void igmp6_send(struct in6_addr *addr, struct net_device *dev, int type)
1933 {
1934 	struct net *net = dev_net(dev);
1935 	struct sock *sk = net->ipv6.igmp_sk;
1936 	struct inet6_dev *idev;
1937 	struct sk_buff *skb;
1938 	struct mld_msg *hdr;
1939 	const struct in6_addr *snd_addr, *saddr;
1940 	struct in6_addr addr_buf;
1941 	int hlen = LL_RESERVED_SPACE(dev);
1942 	int tlen = dev->needed_tailroom;
1943 	int err, len, payload_len, full_len;
1944 	u8 ra[8] = { IPPROTO_ICMPV6, 0,
1945 		     IPV6_TLV_ROUTERALERT, 2, 0, 0,
1946 		     IPV6_TLV_PADN, 0 };
1947 	struct flowi6 fl6;
1948 	struct dst_entry *dst;
1949 
1950 	if (type == ICMPV6_MGM_REDUCTION)
1951 		snd_addr = &in6addr_linklocal_allrouters;
1952 	else
1953 		snd_addr = addr;
1954 
1955 	len = sizeof(struct icmp6hdr) + sizeof(struct in6_addr);
1956 	payload_len = len + sizeof(ra);
1957 	full_len = sizeof(struct ipv6hdr) + payload_len;
1958 
1959 	rcu_read_lock();
1960 	IP6_UPD_PO_STATS(net, __in6_dev_get(dev),
1961 		      IPSTATS_MIB_OUT, full_len);
1962 	rcu_read_unlock();
1963 
1964 	skb = sock_alloc_send_skb(sk, hlen + tlen + full_len, 1, &err);
1965 
1966 	if (!skb) {
1967 		rcu_read_lock();
1968 		IP6_INC_STATS(net, __in6_dev_get(dev),
1969 			      IPSTATS_MIB_OUTDISCARDS);
1970 		rcu_read_unlock();
1971 		return;
1972 	}
1973 	skb->priority = TC_PRIO_CONTROL;
1974 	skb_reserve(skb, hlen);
1975 
1976 	if (ipv6_get_lladdr(dev, &addr_buf, IFA_F_TENTATIVE)) {
1977 		/* <draft-ietf-magma-mld-source-05.txt>:
1978 		 * use unspecified address as the source address
1979 		 * when a valid link-local address is not available.
1980 		 */
1981 		saddr = &in6addr_any;
1982 	} else
1983 		saddr = &addr_buf;
1984 
1985 	ip6_mc_hdr(sk, skb, dev, saddr, snd_addr, NEXTHDR_HOP, payload_len);
1986 
1987 	memcpy(skb_put(skb, sizeof(ra)), ra, sizeof(ra));
1988 
1989 	hdr = (struct mld_msg *) skb_put(skb, sizeof(struct mld_msg));
1990 	memset(hdr, 0, sizeof(struct mld_msg));
1991 	hdr->mld_type = type;
1992 	hdr->mld_mca = *addr;
1993 
1994 	hdr->mld_cksum = csum_ipv6_magic(saddr, snd_addr, len,
1995 					 IPPROTO_ICMPV6,
1996 					 csum_partial(hdr, len, 0));
1997 
1998 	rcu_read_lock();
1999 	idev = __in6_dev_get(skb->dev);
2000 
2001 	icmpv6_flow_init(sk, &fl6, type,
2002 			 &ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
2003 			 skb->dev->ifindex);
2004 	dst = icmp6_dst_alloc(skb->dev, &fl6);
2005 	if (IS_ERR(dst)) {
2006 		err = PTR_ERR(dst);
2007 		goto err_out;
2008 	}
2009 
2010 	skb_dst_set(skb, dst);
2011 	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, sk, skb,
2012 		      NULL, skb->dev, dst_output_sk);
2013 out:
2014 	if (!err) {
2015 		ICMP6MSGOUT_INC_STATS(net, idev, type);
2016 		ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
2017 		IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUTMCAST, full_len);
2018 	} else
2019 		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
2020 
2021 	rcu_read_unlock();
2022 	return;
2023 
2024 err_out:
2025 	kfree_skb(skb);
2026 	goto out;
2027 }
2028 
2029 static void mld_send_initial_cr(struct inet6_dev *idev)
2030 {
2031 	struct sk_buff *skb;
2032 	struct ifmcaddr6 *pmc;
2033 	int type;
2034 
2035 	if (mld_in_v1_mode(idev))
2036 		return;
2037 
2038 	skb = NULL;
2039 	read_lock_bh(&idev->lock);
2040 	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
2041 		spin_lock_bh(&pmc->mca_lock);
2042 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
2043 			type = MLD2_CHANGE_TO_EXCLUDE;
2044 		else
2045 			type = MLD2_CHANGE_TO_INCLUDE;
2046 		skb = add_grec(skb, pmc, type, 0, 0, 1);
2047 		spin_unlock_bh(&pmc->mca_lock);
2048 	}
2049 	read_unlock_bh(&idev->lock);
2050 	if (skb)
2051 		mld_sendpack(skb);
2052 }
2053 
2054 void ipv6_mc_dad_complete(struct inet6_dev *idev)
2055 {
2056 	idev->mc_dad_count = idev->mc_qrv;
2057 	if (idev->mc_dad_count) {
2058 		mld_send_initial_cr(idev);
2059 		idev->mc_dad_count--;
2060 		if (idev->mc_dad_count)
2061 			mld_dad_start_timer(idev, idev->mc_maxdelay);
2062 	}
2063 }
2064 
2065 static void mld_dad_timer_expire(unsigned long data)
2066 {
2067 	struct inet6_dev *idev = (struct inet6_dev *)data;
2068 
2069 	mld_send_initial_cr(idev);
2070 	if (idev->mc_dad_count) {
2071 		idev->mc_dad_count--;
2072 		if (idev->mc_dad_count)
2073 			mld_dad_start_timer(idev, idev->mc_maxdelay);
2074 	}
2075 	in6_dev_put(idev);
2076 }
2077 
2078 static int ip6_mc_del1_src(struct ifmcaddr6 *pmc, int sfmode,
2079 	const struct in6_addr *psfsrc)
2080 {
2081 	struct ip6_sf_list *psf, *psf_prev;
2082 	int rv = 0;
2083 
2084 	psf_prev = NULL;
2085 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
2086 		if (ipv6_addr_equal(&psf->sf_addr, psfsrc))
2087 			break;
2088 		psf_prev = psf;
2089 	}
2090 	if (!psf || psf->sf_count[sfmode] == 0) {
2091 		/* source filter not found, or count wrong =>  bug */
2092 		return -ESRCH;
2093 	}
2094 	psf->sf_count[sfmode]--;
2095 	if (!psf->sf_count[MCAST_INCLUDE] && !psf->sf_count[MCAST_EXCLUDE]) {
2096 		struct inet6_dev *idev = pmc->idev;
2097 
2098 		/* no more filters for this source */
2099 		if (psf_prev)
2100 			psf_prev->sf_next = psf->sf_next;
2101 		else
2102 			pmc->mca_sources = psf->sf_next;
2103 		if (psf->sf_oldin && !(pmc->mca_flags & MAF_NOREPORT) &&
2104 		    !mld_in_v1_mode(idev)) {
2105 			psf->sf_crcount = idev->mc_qrv;
2106 			psf->sf_next = pmc->mca_tomb;
2107 			pmc->mca_tomb = psf;
2108 			rv = 1;
2109 		} else
2110 			kfree(psf);
2111 	}
2112 	return rv;
2113 }
2114 
2115 static int ip6_mc_del_src(struct inet6_dev *idev, const struct in6_addr *pmca,
2116 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
2117 			  int delta)
2118 {
2119 	struct ifmcaddr6 *pmc;
2120 	int	changerec = 0;
2121 	int	i, err;
2122 
2123 	if (!idev)
2124 		return -ENODEV;
2125 	read_lock_bh(&idev->lock);
2126 	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
2127 		if (ipv6_addr_equal(pmca, &pmc->mca_addr))
2128 			break;
2129 	}
2130 	if (!pmc) {
2131 		/* MCA not found?? bug */
2132 		read_unlock_bh(&idev->lock);
2133 		return -ESRCH;
2134 	}
2135 	spin_lock_bh(&pmc->mca_lock);
2136 	sf_markstate(pmc);
2137 	if (!delta) {
2138 		if (!pmc->mca_sfcount[sfmode]) {
2139 			spin_unlock_bh(&pmc->mca_lock);
2140 			read_unlock_bh(&idev->lock);
2141 			return -EINVAL;
2142 		}
2143 		pmc->mca_sfcount[sfmode]--;
2144 	}
2145 	err = 0;
2146 	for (i = 0; i < sfcount; i++) {
2147 		int rv = ip6_mc_del1_src(pmc, sfmode, &psfsrc[i]);
2148 
2149 		changerec |= rv > 0;
2150 		if (!err && rv < 0)
2151 			err = rv;
2152 	}
2153 	if (pmc->mca_sfmode == MCAST_EXCLUDE &&
2154 	    pmc->mca_sfcount[MCAST_EXCLUDE] == 0 &&
2155 	    pmc->mca_sfcount[MCAST_INCLUDE]) {
2156 		struct ip6_sf_list *psf;
2157 
2158 		/* filter mode change */
2159 		pmc->mca_sfmode = MCAST_INCLUDE;
2160 		pmc->mca_crcount = idev->mc_qrv;
2161 		idev->mc_ifc_count = pmc->mca_crcount;
2162 		for (psf = pmc->mca_sources; psf; psf = psf->sf_next)
2163 			psf->sf_crcount = 0;
2164 		mld_ifc_event(pmc->idev);
2165 	} else if (sf_setstate(pmc) || changerec)
2166 		mld_ifc_event(pmc->idev);
2167 	spin_unlock_bh(&pmc->mca_lock);
2168 	read_unlock_bh(&idev->lock);
2169 	return err;
2170 }
2171 
2172 /*
2173  * Add multicast single-source filter to the interface list
2174  */
2175 static int ip6_mc_add1_src(struct ifmcaddr6 *pmc, int sfmode,
2176 	const struct in6_addr *psfsrc)
2177 {
2178 	struct ip6_sf_list *psf, *psf_prev;
2179 
2180 	psf_prev = NULL;
2181 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
2182 		if (ipv6_addr_equal(&psf->sf_addr, psfsrc))
2183 			break;
2184 		psf_prev = psf;
2185 	}
2186 	if (!psf) {
2187 		psf = kzalloc(sizeof(*psf), GFP_ATOMIC);
2188 		if (!psf)
2189 			return -ENOBUFS;
2190 
2191 		psf->sf_addr = *psfsrc;
2192 		if (psf_prev) {
2193 			psf_prev->sf_next = psf;
2194 		} else
2195 			pmc->mca_sources = psf;
2196 	}
2197 	psf->sf_count[sfmode]++;
2198 	return 0;
2199 }
2200 
2201 static void sf_markstate(struct ifmcaddr6 *pmc)
2202 {
2203 	struct ip6_sf_list *psf;
2204 	int mca_xcount = pmc->mca_sfcount[MCAST_EXCLUDE];
2205 
2206 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next)
2207 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
2208 			psf->sf_oldin = mca_xcount ==
2209 				psf->sf_count[MCAST_EXCLUDE] &&
2210 				!psf->sf_count[MCAST_INCLUDE];
2211 		} else
2212 			psf->sf_oldin = psf->sf_count[MCAST_INCLUDE] != 0;
2213 }
2214 
2215 static int sf_setstate(struct ifmcaddr6 *pmc)
2216 {
2217 	struct ip6_sf_list *psf, *dpsf;
2218 	int mca_xcount = pmc->mca_sfcount[MCAST_EXCLUDE];
2219 	int qrv = pmc->idev->mc_qrv;
2220 	int new_in, rv;
2221 
2222 	rv = 0;
2223 	for (psf = pmc->mca_sources; psf; psf = psf->sf_next) {
2224 		if (pmc->mca_sfcount[MCAST_EXCLUDE]) {
2225 			new_in = mca_xcount == psf->sf_count[MCAST_EXCLUDE] &&
2226 				!psf->sf_count[MCAST_INCLUDE];
2227 		} else
2228 			new_in = psf->sf_count[MCAST_INCLUDE] != 0;
2229 		if (new_in) {
2230 			if (!psf->sf_oldin) {
2231 				struct ip6_sf_list *prev = NULL;
2232 
2233 				for (dpsf = pmc->mca_tomb; dpsf;
2234 				     dpsf = dpsf->sf_next) {
2235 					if (ipv6_addr_equal(&dpsf->sf_addr,
2236 					    &psf->sf_addr))
2237 						break;
2238 					prev = dpsf;
2239 				}
2240 				if (dpsf) {
2241 					if (prev)
2242 						prev->sf_next = dpsf->sf_next;
2243 					else
2244 						pmc->mca_tomb = dpsf->sf_next;
2245 					kfree(dpsf);
2246 				}
2247 				psf->sf_crcount = qrv;
2248 				rv++;
2249 			}
2250 		} else if (psf->sf_oldin) {
2251 			psf->sf_crcount = 0;
2252 			/*
2253 			 * add or update "delete" records if an active filter
2254 			 * is now inactive
2255 			 */
2256 			for (dpsf = pmc->mca_tomb; dpsf; dpsf = dpsf->sf_next)
2257 				if (ipv6_addr_equal(&dpsf->sf_addr,
2258 				    &psf->sf_addr))
2259 					break;
2260 			if (!dpsf) {
2261 				dpsf = kmalloc(sizeof(*dpsf), GFP_ATOMIC);
2262 				if (!dpsf)
2263 					continue;
2264 				*dpsf = *psf;
2265 				/* pmc->mca_lock held by callers */
2266 				dpsf->sf_next = pmc->mca_tomb;
2267 				pmc->mca_tomb = dpsf;
2268 			}
2269 			dpsf->sf_crcount = qrv;
2270 			rv++;
2271 		}
2272 	}
2273 	return rv;
2274 }
2275 
2276 /*
2277  * Add multicast source filter list to the interface list
2278  */
2279 static int ip6_mc_add_src(struct inet6_dev *idev, const struct in6_addr *pmca,
2280 			  int sfmode, int sfcount, const struct in6_addr *psfsrc,
2281 			  int delta)
2282 {
2283 	struct ifmcaddr6 *pmc;
2284 	int	isexclude;
2285 	int	i, err;
2286 
2287 	if (!idev)
2288 		return -ENODEV;
2289 	read_lock_bh(&idev->lock);
2290 	for (pmc = idev->mc_list; pmc; pmc = pmc->next) {
2291 		if (ipv6_addr_equal(pmca, &pmc->mca_addr))
2292 			break;
2293 	}
2294 	if (!pmc) {
2295 		/* MCA not found?? bug */
2296 		read_unlock_bh(&idev->lock);
2297 		return -ESRCH;
2298 	}
2299 	spin_lock_bh(&pmc->mca_lock);
2300 
2301 	sf_markstate(pmc);
2302 	isexclude = pmc->mca_sfmode == MCAST_EXCLUDE;
2303 	if (!delta)
2304 		pmc->mca_sfcount[sfmode]++;
2305 	err = 0;
2306 	for (i = 0; i < sfcount; i++) {
2307 		err = ip6_mc_add1_src(pmc, sfmode, &psfsrc[i]);
2308 		if (err)
2309 			break;
2310 	}
2311 	if (err) {
2312 		int j;
2313 
2314 		if (!delta)
2315 			pmc->mca_sfcount[sfmode]--;
2316 		for (j = 0; j < i; j++)
2317 			ip6_mc_del1_src(pmc, sfmode, &psfsrc[j]);
2318 	} else if (isexclude != (pmc->mca_sfcount[MCAST_EXCLUDE] != 0)) {
2319 		struct ip6_sf_list *psf;
2320 
2321 		/* filter mode change */
2322 		if (pmc->mca_sfcount[MCAST_EXCLUDE])
2323 			pmc->mca_sfmode = MCAST_EXCLUDE;
2324 		else if (pmc->mca_sfcount[MCAST_INCLUDE])
2325 			pmc->mca_sfmode = MCAST_INCLUDE;
2326 		/* else no filters; keep old mode for reports */
2327 
2328 		pmc->mca_crcount = idev->mc_qrv;
2329 		idev->mc_ifc_count = pmc->mca_crcount;
2330 		for (psf = pmc->mca_sources; psf; psf = psf->sf_next)
2331 			psf->sf_crcount = 0;
2332 		mld_ifc_event(idev);
2333 	} else if (sf_setstate(pmc))
2334 		mld_ifc_event(idev);
2335 	spin_unlock_bh(&pmc->mca_lock);
2336 	read_unlock_bh(&idev->lock);
2337 	return err;
2338 }
2339 
2340 static void ip6_mc_clear_src(struct ifmcaddr6 *pmc)
2341 {
2342 	struct ip6_sf_list *psf, *nextpsf;
2343 
2344 	for (psf = pmc->mca_tomb; psf; psf = nextpsf) {
2345 		nextpsf = psf->sf_next;
2346 		kfree(psf);
2347 	}
2348 	pmc->mca_tomb = NULL;
2349 	for (psf = pmc->mca_sources; psf; psf = nextpsf) {
2350 		nextpsf = psf->sf_next;
2351 		kfree(psf);
2352 	}
2353 	pmc->mca_sources = NULL;
2354 	pmc->mca_sfmode = MCAST_EXCLUDE;
2355 	pmc->mca_sfcount[MCAST_INCLUDE] = 0;
2356 	pmc->mca_sfcount[MCAST_EXCLUDE] = 1;
2357 }
2358 
2359 
2360 static void igmp6_join_group(struct ifmcaddr6 *ma)
2361 {
2362 	unsigned long delay;
2363 
2364 	if (ma->mca_flags & MAF_NOREPORT)
2365 		return;
2366 
2367 	igmp6_send(&ma->mca_addr, ma->idev->dev, ICMPV6_MGM_REPORT);
2368 
2369 	delay = prandom_u32() % unsolicited_report_interval(ma->idev);
2370 
2371 	spin_lock_bh(&ma->mca_lock);
2372 	if (del_timer(&ma->mca_timer)) {
2373 		atomic_dec(&ma->mca_refcnt);
2374 		delay = ma->mca_timer.expires - jiffies;
2375 	}
2376 
2377 	if (!mod_timer(&ma->mca_timer, jiffies + delay))
2378 		atomic_inc(&ma->mca_refcnt);
2379 	ma->mca_flags |= MAF_TIMER_RUNNING | MAF_LAST_REPORTER;
2380 	spin_unlock_bh(&ma->mca_lock);
2381 }
2382 
2383 static int ip6_mc_leave_src(struct sock *sk, struct ipv6_mc_socklist *iml,
2384 			    struct inet6_dev *idev)
2385 {
2386 	int err;
2387 
2388 	/* callers have the socket lock and rtnl lock
2389 	 * so no other readers or writers of iml or its sflist
2390 	 */
2391 	if (!iml->sflist) {
2392 		/* any-source empty exclude case */
2393 		return ip6_mc_del_src(idev, &iml->addr, iml->sfmode, 0, NULL, 0);
2394 	}
2395 	err = ip6_mc_del_src(idev, &iml->addr, iml->sfmode,
2396 		iml->sflist->sl_count, iml->sflist->sl_addr, 0);
2397 	sock_kfree_s(sk, iml->sflist, IP6_SFLSIZE(iml->sflist->sl_max));
2398 	iml->sflist = NULL;
2399 	return err;
2400 }
2401 
2402 static void igmp6_leave_group(struct ifmcaddr6 *ma)
2403 {
2404 	if (mld_in_v1_mode(ma->idev)) {
2405 		if (ma->mca_flags & MAF_LAST_REPORTER)
2406 			igmp6_send(&ma->mca_addr, ma->idev->dev,
2407 				ICMPV6_MGM_REDUCTION);
2408 	} else {
2409 		mld_add_delrec(ma->idev, ma);
2410 		mld_ifc_event(ma->idev);
2411 	}
2412 }
2413 
2414 static void mld_gq_timer_expire(unsigned long data)
2415 {
2416 	struct inet6_dev *idev = (struct inet6_dev *)data;
2417 
2418 	idev->mc_gq_running = 0;
2419 	mld_send_report(idev, NULL);
2420 	in6_dev_put(idev);
2421 }
2422 
2423 static void mld_ifc_timer_expire(unsigned long data)
2424 {
2425 	struct inet6_dev *idev = (struct inet6_dev *)data;
2426 
2427 	mld_send_cr(idev);
2428 	if (idev->mc_ifc_count) {
2429 		idev->mc_ifc_count--;
2430 		if (idev->mc_ifc_count)
2431 			mld_ifc_start_timer(idev, idev->mc_maxdelay);
2432 	}
2433 	in6_dev_put(idev);
2434 }
2435 
2436 static void mld_ifc_event(struct inet6_dev *idev)
2437 {
2438 	if (mld_in_v1_mode(idev))
2439 		return;
2440 	idev->mc_ifc_count = idev->mc_qrv;
2441 	mld_ifc_start_timer(idev, 1);
2442 }
2443 
2444 
2445 static void igmp6_timer_handler(unsigned long data)
2446 {
2447 	struct ifmcaddr6 *ma = (struct ifmcaddr6 *) data;
2448 
2449 	if (mld_in_v1_mode(ma->idev))
2450 		igmp6_send(&ma->mca_addr, ma->idev->dev, ICMPV6_MGM_REPORT);
2451 	else
2452 		mld_send_report(ma->idev, ma);
2453 
2454 	spin_lock(&ma->mca_lock);
2455 	ma->mca_flags |=  MAF_LAST_REPORTER;
2456 	ma->mca_flags &= ~MAF_TIMER_RUNNING;
2457 	spin_unlock(&ma->mca_lock);
2458 	ma_put(ma);
2459 }
2460 
2461 /* Device changing type */
2462 
2463 void ipv6_mc_unmap(struct inet6_dev *idev)
2464 {
2465 	struct ifmcaddr6 *i;
2466 
2467 	/* Install multicast list, except for all-nodes (already installed) */
2468 
2469 	read_lock_bh(&idev->lock);
2470 	for (i = idev->mc_list; i; i = i->next)
2471 		igmp6_group_dropped(i);
2472 	read_unlock_bh(&idev->lock);
2473 }
2474 
2475 void ipv6_mc_remap(struct inet6_dev *idev)
2476 {
2477 	ipv6_mc_up(idev);
2478 }
2479 
2480 /* Device going down */
2481 
2482 void ipv6_mc_down(struct inet6_dev *idev)
2483 {
2484 	struct ifmcaddr6 *i;
2485 
2486 	/* Withdraw multicast list */
2487 
2488 	read_lock_bh(&idev->lock);
2489 	mld_ifc_stop_timer(idev);
2490 	mld_gq_stop_timer(idev);
2491 	mld_dad_stop_timer(idev);
2492 
2493 	for (i = idev->mc_list; i; i = i->next)
2494 		igmp6_group_dropped(i);
2495 	read_unlock_bh(&idev->lock);
2496 
2497 	mld_clear_delrec(idev);
2498 }
2499 
2500 static void ipv6_mc_reset(struct inet6_dev *idev)
2501 {
2502 	idev->mc_qrv = sysctl_mld_qrv;
2503 	idev->mc_qi = MLD_QI_DEFAULT;
2504 	idev->mc_qri = MLD_QRI_DEFAULT;
2505 	idev->mc_v1_seen = 0;
2506 	idev->mc_maxdelay = unsolicited_report_interval(idev);
2507 }
2508 
2509 /* Device going up */
2510 
2511 void ipv6_mc_up(struct inet6_dev *idev)
2512 {
2513 	struct ifmcaddr6 *i;
2514 
2515 	/* Install multicast list, except for all-nodes (already installed) */
2516 
2517 	read_lock_bh(&idev->lock);
2518 	ipv6_mc_reset(idev);
2519 	for (i = idev->mc_list; i; i = i->next)
2520 		igmp6_group_added(i);
2521 	read_unlock_bh(&idev->lock);
2522 }
2523 
2524 /* IPv6 device initialization. */
2525 
2526 void ipv6_mc_init_dev(struct inet6_dev *idev)
2527 {
2528 	write_lock_bh(&idev->lock);
2529 	spin_lock_init(&idev->mc_lock);
2530 	idev->mc_gq_running = 0;
2531 	setup_timer(&idev->mc_gq_timer, mld_gq_timer_expire,
2532 			(unsigned long)idev);
2533 	idev->mc_tomb = NULL;
2534 	idev->mc_ifc_count = 0;
2535 	setup_timer(&idev->mc_ifc_timer, mld_ifc_timer_expire,
2536 			(unsigned long)idev);
2537 	setup_timer(&idev->mc_dad_timer, mld_dad_timer_expire,
2538 		    (unsigned long)idev);
2539 	ipv6_mc_reset(idev);
2540 	write_unlock_bh(&idev->lock);
2541 }
2542 
2543 /*
2544  *	Device is about to be destroyed: clean up.
2545  */
2546 
2547 void ipv6_mc_destroy_dev(struct inet6_dev *idev)
2548 {
2549 	struct ifmcaddr6 *i;
2550 
2551 	/* Deactivate timers */
2552 	ipv6_mc_down(idev);
2553 
2554 	/* Delete all-nodes address. */
2555 	/* We cannot call ipv6_dev_mc_dec() directly, our caller in
2556 	 * addrconf.c has NULL'd out dev->ip6_ptr so in6_dev_get() will
2557 	 * fail.
2558 	 */
2559 	__ipv6_dev_mc_dec(idev, &in6addr_linklocal_allnodes);
2560 
2561 	if (idev->cnf.forwarding)
2562 		__ipv6_dev_mc_dec(idev, &in6addr_linklocal_allrouters);
2563 
2564 	write_lock_bh(&idev->lock);
2565 	while ((i = idev->mc_list) != NULL) {
2566 		idev->mc_list = i->next;
2567 		write_unlock_bh(&idev->lock);
2568 
2569 		igmp6_group_dropped(i);
2570 		ma_put(i);
2571 
2572 		write_lock_bh(&idev->lock);
2573 	}
2574 	write_unlock_bh(&idev->lock);
2575 }
2576 
2577 #ifdef CONFIG_PROC_FS
2578 struct igmp6_mc_iter_state {
2579 	struct seq_net_private p;
2580 	struct net_device *dev;
2581 	struct inet6_dev *idev;
2582 };
2583 
2584 #define igmp6_mc_seq_private(seq)	((struct igmp6_mc_iter_state *)(seq)->private)
2585 
2586 static inline struct ifmcaddr6 *igmp6_mc_get_first(struct seq_file *seq)
2587 {
2588 	struct ifmcaddr6 *im = NULL;
2589 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2590 	struct net *net = seq_file_net(seq);
2591 
2592 	state->idev = NULL;
2593 	for_each_netdev_rcu(net, state->dev) {
2594 		struct inet6_dev *idev;
2595 		idev = __in6_dev_get(state->dev);
2596 		if (!idev)
2597 			continue;
2598 		read_lock_bh(&idev->lock);
2599 		im = idev->mc_list;
2600 		if (im) {
2601 			state->idev = idev;
2602 			break;
2603 		}
2604 		read_unlock_bh(&idev->lock);
2605 	}
2606 	return im;
2607 }
2608 
2609 static struct ifmcaddr6 *igmp6_mc_get_next(struct seq_file *seq, struct ifmcaddr6 *im)
2610 {
2611 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2612 
2613 	im = im->next;
2614 	while (!im) {
2615 		if (likely(state->idev))
2616 			read_unlock_bh(&state->idev->lock);
2617 
2618 		state->dev = next_net_device_rcu(state->dev);
2619 		if (!state->dev) {
2620 			state->idev = NULL;
2621 			break;
2622 		}
2623 		state->idev = __in6_dev_get(state->dev);
2624 		if (!state->idev)
2625 			continue;
2626 		read_lock_bh(&state->idev->lock);
2627 		im = state->idev->mc_list;
2628 	}
2629 	return im;
2630 }
2631 
2632 static struct ifmcaddr6 *igmp6_mc_get_idx(struct seq_file *seq, loff_t pos)
2633 {
2634 	struct ifmcaddr6 *im = igmp6_mc_get_first(seq);
2635 	if (im)
2636 		while (pos && (im = igmp6_mc_get_next(seq, im)) != NULL)
2637 			--pos;
2638 	return pos ? NULL : im;
2639 }
2640 
2641 static void *igmp6_mc_seq_start(struct seq_file *seq, loff_t *pos)
2642 	__acquires(RCU)
2643 {
2644 	rcu_read_lock();
2645 	return igmp6_mc_get_idx(seq, *pos);
2646 }
2647 
2648 static void *igmp6_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2649 {
2650 	struct ifmcaddr6 *im = igmp6_mc_get_next(seq, v);
2651 
2652 	++*pos;
2653 	return im;
2654 }
2655 
2656 static void igmp6_mc_seq_stop(struct seq_file *seq, void *v)
2657 	__releases(RCU)
2658 {
2659 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2660 
2661 	if (likely(state->idev)) {
2662 		read_unlock_bh(&state->idev->lock);
2663 		state->idev = NULL;
2664 	}
2665 	state->dev = NULL;
2666 	rcu_read_unlock();
2667 }
2668 
2669 static int igmp6_mc_seq_show(struct seq_file *seq, void *v)
2670 {
2671 	struct ifmcaddr6 *im = (struct ifmcaddr6 *)v;
2672 	struct igmp6_mc_iter_state *state = igmp6_mc_seq_private(seq);
2673 
2674 	seq_printf(seq,
2675 		   "%-4d %-15s %pi6 %5d %08X %ld\n",
2676 		   state->dev->ifindex, state->dev->name,
2677 		   &im->mca_addr,
2678 		   im->mca_users, im->mca_flags,
2679 		   (im->mca_flags&MAF_TIMER_RUNNING) ?
2680 		   jiffies_to_clock_t(im->mca_timer.expires-jiffies) : 0);
2681 	return 0;
2682 }
2683 
2684 static const struct seq_operations igmp6_mc_seq_ops = {
2685 	.start	=	igmp6_mc_seq_start,
2686 	.next	=	igmp6_mc_seq_next,
2687 	.stop	=	igmp6_mc_seq_stop,
2688 	.show	=	igmp6_mc_seq_show,
2689 };
2690 
2691 static int igmp6_mc_seq_open(struct inode *inode, struct file *file)
2692 {
2693 	return seq_open_net(inode, file, &igmp6_mc_seq_ops,
2694 			    sizeof(struct igmp6_mc_iter_state));
2695 }
2696 
2697 static const struct file_operations igmp6_mc_seq_fops = {
2698 	.owner		=	THIS_MODULE,
2699 	.open		=	igmp6_mc_seq_open,
2700 	.read		=	seq_read,
2701 	.llseek		=	seq_lseek,
2702 	.release	=	seq_release_net,
2703 };
2704 
2705 struct igmp6_mcf_iter_state {
2706 	struct seq_net_private p;
2707 	struct net_device *dev;
2708 	struct inet6_dev *idev;
2709 	struct ifmcaddr6 *im;
2710 };
2711 
2712 #define igmp6_mcf_seq_private(seq)	((struct igmp6_mcf_iter_state *)(seq)->private)
2713 
2714 static inline struct ip6_sf_list *igmp6_mcf_get_first(struct seq_file *seq)
2715 {
2716 	struct ip6_sf_list *psf = NULL;
2717 	struct ifmcaddr6 *im = NULL;
2718 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
2719 	struct net *net = seq_file_net(seq);
2720 
2721 	state->idev = NULL;
2722 	state->im = NULL;
2723 	for_each_netdev_rcu(net, state->dev) {
2724 		struct inet6_dev *idev;
2725 		idev = __in6_dev_get(state->dev);
2726 		if (unlikely(idev == NULL))
2727 			continue;
2728 		read_lock_bh(&idev->lock);
2729 		im = idev->mc_list;
2730 		if (likely(im)) {
2731 			spin_lock_bh(&im->mca_lock);
2732 			psf = im->mca_sources;
2733 			if (likely(psf)) {
2734 				state->im = im;
2735 				state->idev = idev;
2736 				break;
2737 			}
2738 			spin_unlock_bh(&im->mca_lock);
2739 		}
2740 		read_unlock_bh(&idev->lock);
2741 	}
2742 	return psf;
2743 }
2744 
2745 static struct ip6_sf_list *igmp6_mcf_get_next(struct seq_file *seq, struct ip6_sf_list *psf)
2746 {
2747 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
2748 
2749 	psf = psf->sf_next;
2750 	while (!psf) {
2751 		spin_unlock_bh(&state->im->mca_lock);
2752 		state->im = state->im->next;
2753 		while (!state->im) {
2754 			if (likely(state->idev))
2755 				read_unlock_bh(&state->idev->lock);
2756 
2757 			state->dev = next_net_device_rcu(state->dev);
2758 			if (!state->dev) {
2759 				state->idev = NULL;
2760 				goto out;
2761 			}
2762 			state->idev = __in6_dev_get(state->dev);
2763 			if (!state->idev)
2764 				continue;
2765 			read_lock_bh(&state->idev->lock);
2766 			state->im = state->idev->mc_list;
2767 		}
2768 		if (!state->im)
2769 			break;
2770 		spin_lock_bh(&state->im->mca_lock);
2771 		psf = state->im->mca_sources;
2772 	}
2773 out:
2774 	return psf;
2775 }
2776 
2777 static struct ip6_sf_list *igmp6_mcf_get_idx(struct seq_file *seq, loff_t pos)
2778 {
2779 	struct ip6_sf_list *psf = igmp6_mcf_get_first(seq);
2780 	if (psf)
2781 		while (pos && (psf = igmp6_mcf_get_next(seq, psf)) != NULL)
2782 			--pos;
2783 	return pos ? NULL : psf;
2784 }
2785 
2786 static void *igmp6_mcf_seq_start(struct seq_file *seq, loff_t *pos)
2787 	__acquires(RCU)
2788 {
2789 	rcu_read_lock();
2790 	return *pos ? igmp6_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
2791 }
2792 
2793 static void *igmp6_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2794 {
2795 	struct ip6_sf_list *psf;
2796 	if (v == SEQ_START_TOKEN)
2797 		psf = igmp6_mcf_get_first(seq);
2798 	else
2799 		psf = igmp6_mcf_get_next(seq, v);
2800 	++*pos;
2801 	return psf;
2802 }
2803 
2804 static void igmp6_mcf_seq_stop(struct seq_file *seq, void *v)
2805 	__releases(RCU)
2806 {
2807 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
2808 	if (likely(state->im)) {
2809 		spin_unlock_bh(&state->im->mca_lock);
2810 		state->im = NULL;
2811 	}
2812 	if (likely(state->idev)) {
2813 		read_unlock_bh(&state->idev->lock);
2814 		state->idev = NULL;
2815 	}
2816 	state->dev = NULL;
2817 	rcu_read_unlock();
2818 }
2819 
2820 static int igmp6_mcf_seq_show(struct seq_file *seq, void *v)
2821 {
2822 	struct ip6_sf_list *psf = (struct ip6_sf_list *)v;
2823 	struct igmp6_mcf_iter_state *state = igmp6_mcf_seq_private(seq);
2824 
2825 	if (v == SEQ_START_TOKEN) {
2826 		seq_puts(seq, "Idx Device                Multicast Address                   Source Address    INC    EXC\n");
2827 	} else {
2828 		seq_printf(seq,
2829 			   "%3d %6.6s %pi6 %pi6 %6lu %6lu\n",
2830 			   state->dev->ifindex, state->dev->name,
2831 			   &state->im->mca_addr,
2832 			   &psf->sf_addr,
2833 			   psf->sf_count[MCAST_INCLUDE],
2834 			   psf->sf_count[MCAST_EXCLUDE]);
2835 	}
2836 	return 0;
2837 }
2838 
2839 static const struct seq_operations igmp6_mcf_seq_ops = {
2840 	.start	=	igmp6_mcf_seq_start,
2841 	.next	=	igmp6_mcf_seq_next,
2842 	.stop	=	igmp6_mcf_seq_stop,
2843 	.show	=	igmp6_mcf_seq_show,
2844 };
2845 
2846 static int igmp6_mcf_seq_open(struct inode *inode, struct file *file)
2847 {
2848 	return seq_open_net(inode, file, &igmp6_mcf_seq_ops,
2849 			    sizeof(struct igmp6_mcf_iter_state));
2850 }
2851 
2852 static const struct file_operations igmp6_mcf_seq_fops = {
2853 	.owner		=	THIS_MODULE,
2854 	.open		=	igmp6_mcf_seq_open,
2855 	.read		=	seq_read,
2856 	.llseek		=	seq_lseek,
2857 	.release	=	seq_release_net,
2858 };
2859 
2860 static int __net_init igmp6_proc_init(struct net *net)
2861 {
2862 	int err;
2863 
2864 	err = -ENOMEM;
2865 	if (!proc_create("igmp6", S_IRUGO, net->proc_net, &igmp6_mc_seq_fops))
2866 		goto out;
2867 	if (!proc_create("mcfilter6", S_IRUGO, net->proc_net,
2868 			 &igmp6_mcf_seq_fops))
2869 		goto out_proc_net_igmp6;
2870 
2871 	err = 0;
2872 out:
2873 	return err;
2874 
2875 out_proc_net_igmp6:
2876 	remove_proc_entry("igmp6", net->proc_net);
2877 	goto out;
2878 }
2879 
2880 static void __net_exit igmp6_proc_exit(struct net *net)
2881 {
2882 	remove_proc_entry("mcfilter6", net->proc_net);
2883 	remove_proc_entry("igmp6", net->proc_net);
2884 }
2885 #else
2886 static inline int igmp6_proc_init(struct net *net)
2887 {
2888 	return 0;
2889 }
2890 static inline void igmp6_proc_exit(struct net *net)
2891 {
2892 }
2893 #endif
2894 
2895 static int __net_init igmp6_net_init(struct net *net)
2896 {
2897 	int err;
2898 
2899 	err = inet_ctl_sock_create(&net->ipv6.igmp_sk, PF_INET6,
2900 				   SOCK_RAW, IPPROTO_ICMPV6, net);
2901 	if (err < 0) {
2902 		pr_err("Failed to initialize the IGMP6 control socket (err %d)\n",
2903 		       err);
2904 		goto out;
2905 	}
2906 
2907 	inet6_sk(net->ipv6.igmp_sk)->hop_limit = 1;
2908 
2909 	err = inet_ctl_sock_create(&net->ipv6.mc_autojoin_sk, PF_INET6,
2910 				   SOCK_RAW, IPPROTO_ICMPV6, net);
2911 	if (err < 0) {
2912 		pr_err("Failed to initialize the IGMP6 autojoin socket (err %d)\n",
2913 		       err);
2914 		goto out_sock_create;
2915 	}
2916 
2917 	err = igmp6_proc_init(net);
2918 	if (err)
2919 		goto out_sock_create_autojoin;
2920 
2921 	return 0;
2922 
2923 out_sock_create_autojoin:
2924 	inet_ctl_sock_destroy(net->ipv6.mc_autojoin_sk);
2925 out_sock_create:
2926 	inet_ctl_sock_destroy(net->ipv6.igmp_sk);
2927 out:
2928 	return err;
2929 }
2930 
2931 static void __net_exit igmp6_net_exit(struct net *net)
2932 {
2933 	inet_ctl_sock_destroy(net->ipv6.igmp_sk);
2934 	inet_ctl_sock_destroy(net->ipv6.mc_autojoin_sk);
2935 	igmp6_proc_exit(net);
2936 }
2937 
2938 static struct pernet_operations igmp6_net_ops = {
2939 	.init = igmp6_net_init,
2940 	.exit = igmp6_net_exit,
2941 };
2942 
2943 int __init igmp6_init(void)
2944 {
2945 	return register_pernet_subsys(&igmp6_net_ops);
2946 }
2947 
2948 void igmp6_cleanup(void)
2949 {
2950 	unregister_pernet_subsys(&igmp6_net_ops);
2951 }
2952