xref: /linux/net/bridge/br_multicast.c (revision 93d90ad708b8da6efc0e487b66111aa9db7f70c7)
1 /*
2  * Bridge multicast support.
3  *
4  * Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au>
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License as published by the Free
8  * Software Foundation; either version 2 of the License, or (at your option)
9  * any later version.
10  *
11  */
12 
13 #include <linux/err.h>
14 #include <linux/export.h>
15 #include <linux/if_ether.h>
16 #include <linux/igmp.h>
17 #include <linux/jhash.h>
18 #include <linux/kernel.h>
19 #include <linux/log2.h>
20 #include <linux/netdevice.h>
21 #include <linux/netfilter_bridge.h>
22 #include <linux/random.h>
23 #include <linux/rculist.h>
24 #include <linux/skbuff.h>
25 #include <linux/slab.h>
26 #include <linux/timer.h>
27 #include <linux/inetdevice.h>
28 #include <net/ip.h>
29 #if IS_ENABLED(CONFIG_IPV6)
30 #include <net/ipv6.h>
31 #include <net/mld.h>
32 #include <net/ip6_checksum.h>
33 #include <net/addrconf.h>
34 #endif
35 
36 #include "br_private.h"
37 
38 static void br_multicast_start_querier(struct net_bridge *br,
39 				       struct bridge_mcast_own_query *query);
40 unsigned int br_mdb_rehash_seq;
41 
42 static inline int br_ip_equal(const struct br_ip *a, const struct br_ip *b)
43 {
44 	if (a->proto != b->proto)
45 		return 0;
46 	if (a->vid != b->vid)
47 		return 0;
48 	switch (a->proto) {
49 	case htons(ETH_P_IP):
50 		return a->u.ip4 == b->u.ip4;
51 #if IS_ENABLED(CONFIG_IPV6)
52 	case htons(ETH_P_IPV6):
53 		return ipv6_addr_equal(&a->u.ip6, &b->u.ip6);
54 #endif
55 	}
56 	return 0;
57 }
58 
59 static inline int __br_ip4_hash(struct net_bridge_mdb_htable *mdb, __be32 ip,
60 				__u16 vid)
61 {
62 	return jhash_2words((__force u32)ip, vid, mdb->secret) & (mdb->max - 1);
63 }
64 
65 #if IS_ENABLED(CONFIG_IPV6)
66 static inline int __br_ip6_hash(struct net_bridge_mdb_htable *mdb,
67 				const struct in6_addr *ip,
68 				__u16 vid)
69 {
70 	return jhash_2words(ipv6_addr_hash(ip), vid,
71 			    mdb->secret) & (mdb->max - 1);
72 }
73 #endif
74 
75 static inline int br_ip_hash(struct net_bridge_mdb_htable *mdb,
76 			     struct br_ip *ip)
77 {
78 	switch (ip->proto) {
79 	case htons(ETH_P_IP):
80 		return __br_ip4_hash(mdb, ip->u.ip4, ip->vid);
81 #if IS_ENABLED(CONFIG_IPV6)
82 	case htons(ETH_P_IPV6):
83 		return __br_ip6_hash(mdb, &ip->u.ip6, ip->vid);
84 #endif
85 	}
86 	return 0;
87 }
88 
89 static struct net_bridge_mdb_entry *__br_mdb_ip_get(
90 	struct net_bridge_mdb_htable *mdb, struct br_ip *dst, int hash)
91 {
92 	struct net_bridge_mdb_entry *mp;
93 
94 	hlist_for_each_entry_rcu(mp, &mdb->mhash[hash], hlist[mdb->ver]) {
95 		if (br_ip_equal(&mp->addr, dst))
96 			return mp;
97 	}
98 
99 	return NULL;
100 }
101 
102 struct net_bridge_mdb_entry *br_mdb_ip_get(struct net_bridge_mdb_htable *mdb,
103 					   struct br_ip *dst)
104 {
105 	if (!mdb)
106 		return NULL;
107 
108 	return __br_mdb_ip_get(mdb, dst, br_ip_hash(mdb, dst));
109 }
110 
111 static struct net_bridge_mdb_entry *br_mdb_ip4_get(
112 	struct net_bridge_mdb_htable *mdb, __be32 dst, __u16 vid)
113 {
114 	struct br_ip br_dst;
115 
116 	br_dst.u.ip4 = dst;
117 	br_dst.proto = htons(ETH_P_IP);
118 	br_dst.vid = vid;
119 
120 	return br_mdb_ip_get(mdb, &br_dst);
121 }
122 
123 #if IS_ENABLED(CONFIG_IPV6)
124 static struct net_bridge_mdb_entry *br_mdb_ip6_get(
125 	struct net_bridge_mdb_htable *mdb, const struct in6_addr *dst,
126 	__u16 vid)
127 {
128 	struct br_ip br_dst;
129 
130 	br_dst.u.ip6 = *dst;
131 	br_dst.proto = htons(ETH_P_IPV6);
132 	br_dst.vid = vid;
133 
134 	return br_mdb_ip_get(mdb, &br_dst);
135 }
136 #endif
137 
138 struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br,
139 					struct sk_buff *skb, u16 vid)
140 {
141 	struct net_bridge_mdb_htable *mdb = rcu_dereference(br->mdb);
142 	struct br_ip ip;
143 
144 	if (br->multicast_disabled)
145 		return NULL;
146 
147 	if (BR_INPUT_SKB_CB(skb)->igmp)
148 		return NULL;
149 
150 	ip.proto = skb->protocol;
151 	ip.vid = vid;
152 
153 	switch (skb->protocol) {
154 	case htons(ETH_P_IP):
155 		ip.u.ip4 = ip_hdr(skb)->daddr;
156 		break;
157 #if IS_ENABLED(CONFIG_IPV6)
158 	case htons(ETH_P_IPV6):
159 		ip.u.ip6 = ipv6_hdr(skb)->daddr;
160 		break;
161 #endif
162 	default:
163 		return NULL;
164 	}
165 
166 	return br_mdb_ip_get(mdb, &ip);
167 }
168 
169 static void br_mdb_free(struct rcu_head *head)
170 {
171 	struct net_bridge_mdb_htable *mdb =
172 		container_of(head, struct net_bridge_mdb_htable, rcu);
173 	struct net_bridge_mdb_htable *old = mdb->old;
174 
175 	mdb->old = NULL;
176 	kfree(old->mhash);
177 	kfree(old);
178 }
179 
180 static int br_mdb_copy(struct net_bridge_mdb_htable *new,
181 		       struct net_bridge_mdb_htable *old,
182 		       int elasticity)
183 {
184 	struct net_bridge_mdb_entry *mp;
185 	int maxlen;
186 	int len;
187 	int i;
188 
189 	for (i = 0; i < old->max; i++)
190 		hlist_for_each_entry(mp, &old->mhash[i], hlist[old->ver])
191 			hlist_add_head(&mp->hlist[new->ver],
192 				       &new->mhash[br_ip_hash(new, &mp->addr)]);
193 
194 	if (!elasticity)
195 		return 0;
196 
197 	maxlen = 0;
198 	for (i = 0; i < new->max; i++) {
199 		len = 0;
200 		hlist_for_each_entry(mp, &new->mhash[i], hlist[new->ver])
201 			len++;
202 		if (len > maxlen)
203 			maxlen = len;
204 	}
205 
206 	return maxlen > elasticity ? -EINVAL : 0;
207 }
208 
209 void br_multicast_free_pg(struct rcu_head *head)
210 {
211 	struct net_bridge_port_group *p =
212 		container_of(head, struct net_bridge_port_group, rcu);
213 
214 	kfree(p);
215 }
216 
217 static void br_multicast_free_group(struct rcu_head *head)
218 {
219 	struct net_bridge_mdb_entry *mp =
220 		container_of(head, struct net_bridge_mdb_entry, rcu);
221 
222 	kfree(mp);
223 }
224 
225 static void br_multicast_group_expired(unsigned long data)
226 {
227 	struct net_bridge_mdb_entry *mp = (void *)data;
228 	struct net_bridge *br = mp->br;
229 	struct net_bridge_mdb_htable *mdb;
230 
231 	spin_lock(&br->multicast_lock);
232 	if (!netif_running(br->dev) || timer_pending(&mp->timer))
233 		goto out;
234 
235 	mp->mglist = false;
236 
237 	if (mp->ports)
238 		goto out;
239 
240 	mdb = mlock_dereference(br->mdb, br);
241 
242 	hlist_del_rcu(&mp->hlist[mdb->ver]);
243 	mdb->size--;
244 
245 	call_rcu_bh(&mp->rcu, br_multicast_free_group);
246 
247 out:
248 	spin_unlock(&br->multicast_lock);
249 }
250 
251 static void br_multicast_del_pg(struct net_bridge *br,
252 				struct net_bridge_port_group *pg)
253 {
254 	struct net_bridge_mdb_htable *mdb;
255 	struct net_bridge_mdb_entry *mp;
256 	struct net_bridge_port_group *p;
257 	struct net_bridge_port_group __rcu **pp;
258 
259 	mdb = mlock_dereference(br->mdb, br);
260 
261 	mp = br_mdb_ip_get(mdb, &pg->addr);
262 	if (WARN_ON(!mp))
263 		return;
264 
265 	for (pp = &mp->ports;
266 	     (p = mlock_dereference(*pp, br)) != NULL;
267 	     pp = &p->next) {
268 		if (p != pg)
269 			continue;
270 
271 		rcu_assign_pointer(*pp, p->next);
272 		hlist_del_init(&p->mglist);
273 		del_timer(&p->timer);
274 		call_rcu_bh(&p->rcu, br_multicast_free_pg);
275 
276 		if (!mp->ports && !mp->mglist &&
277 		    netif_running(br->dev))
278 			mod_timer(&mp->timer, jiffies);
279 
280 		return;
281 	}
282 
283 	WARN_ON(1);
284 }
285 
286 static void br_multicast_port_group_expired(unsigned long data)
287 {
288 	struct net_bridge_port_group *pg = (void *)data;
289 	struct net_bridge *br = pg->port->br;
290 
291 	spin_lock(&br->multicast_lock);
292 	if (!netif_running(br->dev) || timer_pending(&pg->timer) ||
293 	    hlist_unhashed(&pg->mglist) || pg->state & MDB_PERMANENT)
294 		goto out;
295 
296 	br_multicast_del_pg(br, pg);
297 
298 out:
299 	spin_unlock(&br->multicast_lock);
300 }
301 
302 static int br_mdb_rehash(struct net_bridge_mdb_htable __rcu **mdbp, int max,
303 			 int elasticity)
304 {
305 	struct net_bridge_mdb_htable *old = rcu_dereference_protected(*mdbp, 1);
306 	struct net_bridge_mdb_htable *mdb;
307 	int err;
308 
309 	mdb = kmalloc(sizeof(*mdb), GFP_ATOMIC);
310 	if (!mdb)
311 		return -ENOMEM;
312 
313 	mdb->max = max;
314 	mdb->old = old;
315 
316 	mdb->mhash = kzalloc(max * sizeof(*mdb->mhash), GFP_ATOMIC);
317 	if (!mdb->mhash) {
318 		kfree(mdb);
319 		return -ENOMEM;
320 	}
321 
322 	mdb->size = old ? old->size : 0;
323 	mdb->ver = old ? old->ver ^ 1 : 0;
324 
325 	if (!old || elasticity)
326 		get_random_bytes(&mdb->secret, sizeof(mdb->secret));
327 	else
328 		mdb->secret = old->secret;
329 
330 	if (!old)
331 		goto out;
332 
333 	err = br_mdb_copy(mdb, old, elasticity);
334 	if (err) {
335 		kfree(mdb->mhash);
336 		kfree(mdb);
337 		return err;
338 	}
339 
340 	br_mdb_rehash_seq++;
341 	call_rcu_bh(&mdb->rcu, br_mdb_free);
342 
343 out:
344 	rcu_assign_pointer(*mdbp, mdb);
345 
346 	return 0;
347 }
348 
349 static struct sk_buff *br_ip4_multicast_alloc_query(struct net_bridge *br,
350 						    __be32 group)
351 {
352 	struct sk_buff *skb;
353 	struct igmphdr *ih;
354 	struct ethhdr *eth;
355 	struct iphdr *iph;
356 
357 	skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*iph) +
358 						 sizeof(*ih) + 4);
359 	if (!skb)
360 		goto out;
361 
362 	skb->protocol = htons(ETH_P_IP);
363 
364 	skb_reset_mac_header(skb);
365 	eth = eth_hdr(skb);
366 
367 	ether_addr_copy(eth->h_source, br->dev->dev_addr);
368 	eth->h_dest[0] = 1;
369 	eth->h_dest[1] = 0;
370 	eth->h_dest[2] = 0x5e;
371 	eth->h_dest[3] = 0;
372 	eth->h_dest[4] = 0;
373 	eth->h_dest[5] = 1;
374 	eth->h_proto = htons(ETH_P_IP);
375 	skb_put(skb, sizeof(*eth));
376 
377 	skb_set_network_header(skb, skb->len);
378 	iph = ip_hdr(skb);
379 
380 	iph->version = 4;
381 	iph->ihl = 6;
382 	iph->tos = 0xc0;
383 	iph->tot_len = htons(sizeof(*iph) + sizeof(*ih) + 4);
384 	iph->id = 0;
385 	iph->frag_off = htons(IP_DF);
386 	iph->ttl = 1;
387 	iph->protocol = IPPROTO_IGMP;
388 	iph->saddr = br->multicast_query_use_ifaddr ?
389 		     inet_select_addr(br->dev, 0, RT_SCOPE_LINK) : 0;
390 	iph->daddr = htonl(INADDR_ALLHOSTS_GROUP);
391 	((u8 *)&iph[1])[0] = IPOPT_RA;
392 	((u8 *)&iph[1])[1] = 4;
393 	((u8 *)&iph[1])[2] = 0;
394 	((u8 *)&iph[1])[3] = 0;
395 	ip_send_check(iph);
396 	skb_put(skb, 24);
397 
398 	skb_set_transport_header(skb, skb->len);
399 	ih = igmp_hdr(skb);
400 	ih->type = IGMP_HOST_MEMBERSHIP_QUERY;
401 	ih->code = (group ? br->multicast_last_member_interval :
402 			    br->multicast_query_response_interval) /
403 		   (HZ / IGMP_TIMER_SCALE);
404 	ih->group = group;
405 	ih->csum = 0;
406 	ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
407 	skb_put(skb, sizeof(*ih));
408 
409 	__skb_pull(skb, sizeof(*eth));
410 
411 out:
412 	return skb;
413 }
414 
415 #if IS_ENABLED(CONFIG_IPV6)
416 static struct sk_buff *br_ip6_multicast_alloc_query(struct net_bridge *br,
417 						    const struct in6_addr *group)
418 {
419 	struct sk_buff *skb;
420 	struct ipv6hdr *ip6h;
421 	struct mld_msg *mldq;
422 	struct ethhdr *eth;
423 	u8 *hopopt;
424 	unsigned long interval;
425 
426 	skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*ip6h) +
427 						 8 + sizeof(*mldq));
428 	if (!skb)
429 		goto out;
430 
431 	skb->protocol = htons(ETH_P_IPV6);
432 
433 	/* Ethernet header */
434 	skb_reset_mac_header(skb);
435 	eth = eth_hdr(skb);
436 
437 	ether_addr_copy(eth->h_source, br->dev->dev_addr);
438 	eth->h_proto = htons(ETH_P_IPV6);
439 	skb_put(skb, sizeof(*eth));
440 
441 	/* IPv6 header + HbH option */
442 	skb_set_network_header(skb, skb->len);
443 	ip6h = ipv6_hdr(skb);
444 
445 	*(__force __be32 *)ip6h = htonl(0x60000000);
446 	ip6h->payload_len = htons(8 + sizeof(*mldq));
447 	ip6h->nexthdr = IPPROTO_HOPOPTS;
448 	ip6h->hop_limit = 1;
449 	ipv6_addr_set(&ip6h->daddr, htonl(0xff020000), 0, 0, htonl(1));
450 	if (ipv6_dev_get_saddr(dev_net(br->dev), br->dev, &ip6h->daddr, 0,
451 			       &ip6h->saddr)) {
452 		kfree_skb(skb);
453 		return NULL;
454 	}
455 	ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest);
456 
457 	hopopt = (u8 *)(ip6h + 1);
458 	hopopt[0] = IPPROTO_ICMPV6;		/* next hdr */
459 	hopopt[1] = 0;				/* length of HbH */
460 	hopopt[2] = IPV6_TLV_ROUTERALERT;	/* Router Alert */
461 	hopopt[3] = 2;				/* Length of RA Option */
462 	hopopt[4] = 0;				/* Type = 0x0000 (MLD) */
463 	hopopt[5] = 0;
464 	hopopt[6] = IPV6_TLV_PAD1;		/* Pad1 */
465 	hopopt[7] = IPV6_TLV_PAD1;		/* Pad1 */
466 
467 	skb_put(skb, sizeof(*ip6h) + 8);
468 
469 	/* ICMPv6 */
470 	skb_set_transport_header(skb, skb->len);
471 	mldq = (struct mld_msg *) icmp6_hdr(skb);
472 
473 	interval = ipv6_addr_any(group) ?
474 			br->multicast_query_response_interval :
475 			br->multicast_last_member_interval;
476 
477 	mldq->mld_type = ICMPV6_MGM_QUERY;
478 	mldq->mld_code = 0;
479 	mldq->mld_cksum = 0;
480 	mldq->mld_maxdelay = htons((u16)jiffies_to_msecs(interval));
481 	mldq->mld_reserved = 0;
482 	mldq->mld_mca = *group;
483 
484 	/* checksum */
485 	mldq->mld_cksum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
486 					  sizeof(*mldq), IPPROTO_ICMPV6,
487 					  csum_partial(mldq,
488 						       sizeof(*mldq), 0));
489 	skb_put(skb, sizeof(*mldq));
490 
491 	__skb_pull(skb, sizeof(*eth));
492 
493 out:
494 	return skb;
495 }
496 #endif
497 
498 static struct sk_buff *br_multicast_alloc_query(struct net_bridge *br,
499 						struct br_ip *addr)
500 {
501 	switch (addr->proto) {
502 	case htons(ETH_P_IP):
503 		return br_ip4_multicast_alloc_query(br, addr->u.ip4);
504 #if IS_ENABLED(CONFIG_IPV6)
505 	case htons(ETH_P_IPV6):
506 		return br_ip6_multicast_alloc_query(br, &addr->u.ip6);
507 #endif
508 	}
509 	return NULL;
510 }
511 
512 static struct net_bridge_mdb_entry *br_multicast_get_group(
513 	struct net_bridge *br, struct net_bridge_port *port,
514 	struct br_ip *group, int hash)
515 {
516 	struct net_bridge_mdb_htable *mdb;
517 	struct net_bridge_mdb_entry *mp;
518 	unsigned int count = 0;
519 	unsigned int max;
520 	int elasticity;
521 	int err;
522 
523 	mdb = rcu_dereference_protected(br->mdb, 1);
524 	hlist_for_each_entry(mp, &mdb->mhash[hash], hlist[mdb->ver]) {
525 		count++;
526 		if (unlikely(br_ip_equal(group, &mp->addr)))
527 			return mp;
528 	}
529 
530 	elasticity = 0;
531 	max = mdb->max;
532 
533 	if (unlikely(count > br->hash_elasticity && count)) {
534 		if (net_ratelimit())
535 			br_info(br, "Multicast hash table "
536 				"chain limit reached: %s\n",
537 				port ? port->dev->name : br->dev->name);
538 
539 		elasticity = br->hash_elasticity;
540 	}
541 
542 	if (mdb->size >= max) {
543 		max *= 2;
544 		if (unlikely(max > br->hash_max)) {
545 			br_warn(br, "Multicast hash table maximum of %d "
546 				"reached, disabling snooping: %s\n",
547 				br->hash_max,
548 				port ? port->dev->name : br->dev->name);
549 			err = -E2BIG;
550 disable:
551 			br->multicast_disabled = 1;
552 			goto err;
553 		}
554 	}
555 
556 	if (max > mdb->max || elasticity) {
557 		if (mdb->old) {
558 			if (net_ratelimit())
559 				br_info(br, "Multicast hash table "
560 					"on fire: %s\n",
561 					port ? port->dev->name : br->dev->name);
562 			err = -EEXIST;
563 			goto err;
564 		}
565 
566 		err = br_mdb_rehash(&br->mdb, max, elasticity);
567 		if (err) {
568 			br_warn(br, "Cannot rehash multicast "
569 				"hash table, disabling snooping: %s, %d, %d\n",
570 				port ? port->dev->name : br->dev->name,
571 				mdb->size, err);
572 			goto disable;
573 		}
574 
575 		err = -EAGAIN;
576 		goto err;
577 	}
578 
579 	return NULL;
580 
581 err:
582 	mp = ERR_PTR(err);
583 	return mp;
584 }
585 
586 struct net_bridge_mdb_entry *br_multicast_new_group(struct net_bridge *br,
587 	struct net_bridge_port *port, struct br_ip *group)
588 {
589 	struct net_bridge_mdb_htable *mdb;
590 	struct net_bridge_mdb_entry *mp;
591 	int hash;
592 	int err;
593 
594 	mdb = rcu_dereference_protected(br->mdb, 1);
595 	if (!mdb) {
596 		err = br_mdb_rehash(&br->mdb, BR_HASH_SIZE, 0);
597 		if (err)
598 			return ERR_PTR(err);
599 		goto rehash;
600 	}
601 
602 	hash = br_ip_hash(mdb, group);
603 	mp = br_multicast_get_group(br, port, group, hash);
604 	switch (PTR_ERR(mp)) {
605 	case 0:
606 		break;
607 
608 	case -EAGAIN:
609 rehash:
610 		mdb = rcu_dereference_protected(br->mdb, 1);
611 		hash = br_ip_hash(mdb, group);
612 		break;
613 
614 	default:
615 		goto out;
616 	}
617 
618 	mp = kzalloc(sizeof(*mp), GFP_ATOMIC);
619 	if (unlikely(!mp))
620 		return ERR_PTR(-ENOMEM);
621 
622 	mp->br = br;
623 	mp->addr = *group;
624 	setup_timer(&mp->timer, br_multicast_group_expired,
625 		    (unsigned long)mp);
626 
627 	hlist_add_head_rcu(&mp->hlist[mdb->ver], &mdb->mhash[hash]);
628 	mdb->size++;
629 
630 out:
631 	return mp;
632 }
633 
634 struct net_bridge_port_group *br_multicast_new_port_group(
635 			struct net_bridge_port *port,
636 			struct br_ip *group,
637 			struct net_bridge_port_group __rcu *next,
638 			unsigned char state)
639 {
640 	struct net_bridge_port_group *p;
641 
642 	p = kzalloc(sizeof(*p), GFP_ATOMIC);
643 	if (unlikely(!p))
644 		return NULL;
645 
646 	p->addr = *group;
647 	p->port = port;
648 	p->state = state;
649 	rcu_assign_pointer(p->next, next);
650 	hlist_add_head(&p->mglist, &port->mglist);
651 	setup_timer(&p->timer, br_multicast_port_group_expired,
652 		    (unsigned long)p);
653 	return p;
654 }
655 
656 static int br_multicast_add_group(struct net_bridge *br,
657 				  struct net_bridge_port *port,
658 				  struct br_ip *group)
659 {
660 	struct net_bridge_mdb_entry *mp;
661 	struct net_bridge_port_group *p;
662 	struct net_bridge_port_group __rcu **pp;
663 	unsigned long now = jiffies;
664 	int err;
665 
666 	spin_lock(&br->multicast_lock);
667 	if (!netif_running(br->dev) ||
668 	    (port && port->state == BR_STATE_DISABLED))
669 		goto out;
670 
671 	mp = br_multicast_new_group(br, port, group);
672 	err = PTR_ERR(mp);
673 	if (IS_ERR(mp))
674 		goto err;
675 
676 	if (!port) {
677 		mp->mglist = true;
678 		mod_timer(&mp->timer, now + br->multicast_membership_interval);
679 		goto out;
680 	}
681 
682 	for (pp = &mp->ports;
683 	     (p = mlock_dereference(*pp, br)) != NULL;
684 	     pp = &p->next) {
685 		if (p->port == port)
686 			goto found;
687 		if ((unsigned long)p->port < (unsigned long)port)
688 			break;
689 	}
690 
691 	p = br_multicast_new_port_group(port, group, *pp, MDB_TEMPORARY);
692 	if (unlikely(!p))
693 		goto err;
694 	rcu_assign_pointer(*pp, p);
695 	br_mdb_notify(br->dev, port, group, RTM_NEWMDB);
696 
697 found:
698 	mod_timer(&p->timer, now + br->multicast_membership_interval);
699 out:
700 	err = 0;
701 
702 err:
703 	spin_unlock(&br->multicast_lock);
704 	return err;
705 }
706 
707 static int br_ip4_multicast_add_group(struct net_bridge *br,
708 				      struct net_bridge_port *port,
709 				      __be32 group,
710 				      __u16 vid)
711 {
712 	struct br_ip br_group;
713 
714 	if (ipv4_is_local_multicast(group))
715 		return 0;
716 
717 	br_group.u.ip4 = group;
718 	br_group.proto = htons(ETH_P_IP);
719 	br_group.vid = vid;
720 
721 	return br_multicast_add_group(br, port, &br_group);
722 }
723 
724 #if IS_ENABLED(CONFIG_IPV6)
725 static int br_ip6_multicast_add_group(struct net_bridge *br,
726 				      struct net_bridge_port *port,
727 				      const struct in6_addr *group,
728 				      __u16 vid)
729 {
730 	struct br_ip br_group;
731 
732 	if (ipv6_addr_is_ll_all_nodes(group))
733 		return 0;
734 
735 	br_group.u.ip6 = *group;
736 	br_group.proto = htons(ETH_P_IPV6);
737 	br_group.vid = vid;
738 
739 	return br_multicast_add_group(br, port, &br_group);
740 }
741 #endif
742 
743 static void br_multicast_router_expired(unsigned long data)
744 {
745 	struct net_bridge_port *port = (void *)data;
746 	struct net_bridge *br = port->br;
747 
748 	spin_lock(&br->multicast_lock);
749 	if (port->multicast_router != 1 ||
750 	    timer_pending(&port->multicast_router_timer) ||
751 	    hlist_unhashed(&port->rlist))
752 		goto out;
753 
754 	hlist_del_init_rcu(&port->rlist);
755 
756 out:
757 	spin_unlock(&br->multicast_lock);
758 }
759 
760 static void br_multicast_local_router_expired(unsigned long data)
761 {
762 }
763 
764 static void br_multicast_querier_expired(struct net_bridge *br,
765 					 struct bridge_mcast_own_query *query)
766 {
767 	spin_lock(&br->multicast_lock);
768 	if (!netif_running(br->dev) || br->multicast_disabled)
769 		goto out;
770 
771 	br_multicast_start_querier(br, query);
772 
773 out:
774 	spin_unlock(&br->multicast_lock);
775 }
776 
777 static void br_ip4_multicast_querier_expired(unsigned long data)
778 {
779 	struct net_bridge *br = (void *)data;
780 
781 	br_multicast_querier_expired(br, &br->ip4_own_query);
782 }
783 
784 #if IS_ENABLED(CONFIG_IPV6)
785 static void br_ip6_multicast_querier_expired(unsigned long data)
786 {
787 	struct net_bridge *br = (void *)data;
788 
789 	br_multicast_querier_expired(br, &br->ip6_own_query);
790 }
791 #endif
792 
793 static void br_multicast_select_own_querier(struct net_bridge *br,
794 					    struct br_ip *ip,
795 					    struct sk_buff *skb)
796 {
797 	if (ip->proto == htons(ETH_P_IP))
798 		br->ip4_querier.addr.u.ip4 = ip_hdr(skb)->saddr;
799 #if IS_ENABLED(CONFIG_IPV6)
800 	else
801 		br->ip6_querier.addr.u.ip6 = ipv6_hdr(skb)->saddr;
802 #endif
803 }
804 
805 static void __br_multicast_send_query(struct net_bridge *br,
806 				      struct net_bridge_port *port,
807 				      struct br_ip *ip)
808 {
809 	struct sk_buff *skb;
810 
811 	skb = br_multicast_alloc_query(br, ip);
812 	if (!skb)
813 		return;
814 
815 	if (port) {
816 		skb->dev = port->dev;
817 		NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
818 			br_dev_queue_push_xmit);
819 	} else {
820 		br_multicast_select_own_querier(br, ip, skb);
821 		netif_rx(skb);
822 	}
823 }
824 
825 static void br_multicast_send_query(struct net_bridge *br,
826 				    struct net_bridge_port *port,
827 				    struct bridge_mcast_own_query *own_query)
828 {
829 	unsigned long time;
830 	struct br_ip br_group;
831 	struct bridge_mcast_other_query *other_query = NULL;
832 
833 	if (!netif_running(br->dev) || br->multicast_disabled ||
834 	    !br->multicast_querier)
835 		return;
836 
837 	memset(&br_group.u, 0, sizeof(br_group.u));
838 
839 	if (port ? (own_query == &port->ip4_own_query) :
840 		   (own_query == &br->ip4_own_query)) {
841 		other_query = &br->ip4_other_query;
842 		br_group.proto = htons(ETH_P_IP);
843 #if IS_ENABLED(CONFIG_IPV6)
844 	} else {
845 		other_query = &br->ip6_other_query;
846 		br_group.proto = htons(ETH_P_IPV6);
847 #endif
848 	}
849 
850 	if (!other_query || timer_pending(&other_query->timer))
851 		return;
852 
853 	__br_multicast_send_query(br, port, &br_group);
854 
855 	time = jiffies;
856 	time += own_query->startup_sent < br->multicast_startup_query_count ?
857 		br->multicast_startup_query_interval :
858 		br->multicast_query_interval;
859 	mod_timer(&own_query->timer, time);
860 }
861 
862 static void
863 br_multicast_port_query_expired(struct net_bridge_port *port,
864 				struct bridge_mcast_own_query *query)
865 {
866 	struct net_bridge *br = port->br;
867 
868 	spin_lock(&br->multicast_lock);
869 	if (port->state == BR_STATE_DISABLED ||
870 	    port->state == BR_STATE_BLOCKING)
871 		goto out;
872 
873 	if (query->startup_sent < br->multicast_startup_query_count)
874 		query->startup_sent++;
875 
876 	br_multicast_send_query(port->br, port, query);
877 
878 out:
879 	spin_unlock(&br->multicast_lock);
880 }
881 
882 static void br_ip4_multicast_port_query_expired(unsigned long data)
883 {
884 	struct net_bridge_port *port = (void *)data;
885 
886 	br_multicast_port_query_expired(port, &port->ip4_own_query);
887 }
888 
889 #if IS_ENABLED(CONFIG_IPV6)
890 static void br_ip6_multicast_port_query_expired(unsigned long data)
891 {
892 	struct net_bridge_port *port = (void *)data;
893 
894 	br_multicast_port_query_expired(port, &port->ip6_own_query);
895 }
896 #endif
897 
898 void br_multicast_add_port(struct net_bridge_port *port)
899 {
900 	port->multicast_router = 1;
901 
902 	setup_timer(&port->multicast_router_timer, br_multicast_router_expired,
903 		    (unsigned long)port);
904 	setup_timer(&port->ip4_own_query.timer,
905 		    br_ip4_multicast_port_query_expired, (unsigned long)port);
906 #if IS_ENABLED(CONFIG_IPV6)
907 	setup_timer(&port->ip6_own_query.timer,
908 		    br_ip6_multicast_port_query_expired, (unsigned long)port);
909 #endif
910 }
911 
912 void br_multicast_del_port(struct net_bridge_port *port)
913 {
914 	del_timer_sync(&port->multicast_router_timer);
915 }
916 
917 static void br_multicast_enable(struct bridge_mcast_own_query *query)
918 {
919 	query->startup_sent = 0;
920 
921 	if (try_to_del_timer_sync(&query->timer) >= 0 ||
922 	    del_timer(&query->timer))
923 		mod_timer(&query->timer, jiffies);
924 }
925 
926 void br_multicast_enable_port(struct net_bridge_port *port)
927 {
928 	struct net_bridge *br = port->br;
929 
930 	spin_lock(&br->multicast_lock);
931 	if (br->multicast_disabled || !netif_running(br->dev))
932 		goto out;
933 
934 	br_multicast_enable(&port->ip4_own_query);
935 #if IS_ENABLED(CONFIG_IPV6)
936 	br_multicast_enable(&port->ip6_own_query);
937 #endif
938 
939 out:
940 	spin_unlock(&br->multicast_lock);
941 }
942 
943 void br_multicast_disable_port(struct net_bridge_port *port)
944 {
945 	struct net_bridge *br = port->br;
946 	struct net_bridge_port_group *pg;
947 	struct hlist_node *n;
948 
949 	spin_lock(&br->multicast_lock);
950 	hlist_for_each_entry_safe(pg, n, &port->mglist, mglist)
951 		br_multicast_del_pg(br, pg);
952 
953 	if (!hlist_unhashed(&port->rlist))
954 		hlist_del_init_rcu(&port->rlist);
955 	del_timer(&port->multicast_router_timer);
956 	del_timer(&port->ip4_own_query.timer);
957 #if IS_ENABLED(CONFIG_IPV6)
958 	del_timer(&port->ip6_own_query.timer);
959 #endif
960 	spin_unlock(&br->multicast_lock);
961 }
962 
963 static int br_ip4_multicast_igmp3_report(struct net_bridge *br,
964 					 struct net_bridge_port *port,
965 					 struct sk_buff *skb,
966 					 u16 vid)
967 {
968 	struct igmpv3_report *ih;
969 	struct igmpv3_grec *grec;
970 	int i;
971 	int len;
972 	int num;
973 	int type;
974 	int err = 0;
975 	__be32 group;
976 
977 	if (!pskb_may_pull(skb, sizeof(*ih)))
978 		return -EINVAL;
979 
980 	ih = igmpv3_report_hdr(skb);
981 	num = ntohs(ih->ngrec);
982 	len = sizeof(*ih);
983 
984 	for (i = 0; i < num; i++) {
985 		len += sizeof(*grec);
986 		if (!pskb_may_pull(skb, len))
987 			return -EINVAL;
988 
989 		grec = (void *)(skb->data + len - sizeof(*grec));
990 		group = grec->grec_mca;
991 		type = grec->grec_type;
992 
993 		len += ntohs(grec->grec_nsrcs) * 4;
994 		if (!pskb_may_pull(skb, len))
995 			return -EINVAL;
996 
997 		/* We treat this as an IGMPv2 report for now. */
998 		switch (type) {
999 		case IGMPV3_MODE_IS_INCLUDE:
1000 		case IGMPV3_MODE_IS_EXCLUDE:
1001 		case IGMPV3_CHANGE_TO_INCLUDE:
1002 		case IGMPV3_CHANGE_TO_EXCLUDE:
1003 		case IGMPV3_ALLOW_NEW_SOURCES:
1004 		case IGMPV3_BLOCK_OLD_SOURCES:
1005 			break;
1006 
1007 		default:
1008 			continue;
1009 		}
1010 
1011 		err = br_ip4_multicast_add_group(br, port, group, vid);
1012 		if (err)
1013 			break;
1014 	}
1015 
1016 	return err;
1017 }
1018 
1019 #if IS_ENABLED(CONFIG_IPV6)
1020 static int br_ip6_multicast_mld2_report(struct net_bridge *br,
1021 					struct net_bridge_port *port,
1022 					struct sk_buff *skb,
1023 					u16 vid)
1024 {
1025 	struct icmp6hdr *icmp6h;
1026 	struct mld2_grec *grec;
1027 	int i;
1028 	int len;
1029 	int num;
1030 	int err = 0;
1031 
1032 	if (!pskb_may_pull(skb, sizeof(*icmp6h)))
1033 		return -EINVAL;
1034 
1035 	icmp6h = icmp6_hdr(skb);
1036 	num = ntohs(icmp6h->icmp6_dataun.un_data16[1]);
1037 	len = sizeof(*icmp6h);
1038 
1039 	for (i = 0; i < num; i++) {
1040 		__be16 *nsrcs, _nsrcs;
1041 
1042 		nsrcs = skb_header_pointer(skb,
1043 					   len + offsetof(struct mld2_grec,
1044 							  grec_nsrcs),
1045 					   sizeof(_nsrcs), &_nsrcs);
1046 		if (!nsrcs)
1047 			return -EINVAL;
1048 
1049 		if (!pskb_may_pull(skb,
1050 				   len + sizeof(*grec) +
1051 				   sizeof(struct in6_addr) * ntohs(*nsrcs)))
1052 			return -EINVAL;
1053 
1054 		grec = (struct mld2_grec *)(skb->data + len);
1055 		len += sizeof(*grec) +
1056 		       sizeof(struct in6_addr) * ntohs(*nsrcs);
1057 
1058 		/* We treat these as MLDv1 reports for now. */
1059 		switch (grec->grec_type) {
1060 		case MLD2_MODE_IS_INCLUDE:
1061 		case MLD2_MODE_IS_EXCLUDE:
1062 		case MLD2_CHANGE_TO_INCLUDE:
1063 		case MLD2_CHANGE_TO_EXCLUDE:
1064 		case MLD2_ALLOW_NEW_SOURCES:
1065 		case MLD2_BLOCK_OLD_SOURCES:
1066 			break;
1067 
1068 		default:
1069 			continue;
1070 		}
1071 
1072 		err = br_ip6_multicast_add_group(br, port, &grec->grec_mca,
1073 						 vid);
1074 		if (!err)
1075 			break;
1076 	}
1077 
1078 	return err;
1079 }
1080 #endif
1081 
1082 static bool br_ip4_multicast_select_querier(struct net_bridge *br,
1083 					    struct net_bridge_port *port,
1084 					    __be32 saddr)
1085 {
1086 	if (!timer_pending(&br->ip4_own_query.timer) &&
1087 	    !timer_pending(&br->ip4_other_query.timer))
1088 		goto update;
1089 
1090 	if (!br->ip4_querier.addr.u.ip4)
1091 		goto update;
1092 
1093 	if (ntohl(saddr) <= ntohl(br->ip4_querier.addr.u.ip4))
1094 		goto update;
1095 
1096 	return false;
1097 
1098 update:
1099 	br->ip4_querier.addr.u.ip4 = saddr;
1100 
1101 	/* update protected by general multicast_lock by caller */
1102 	rcu_assign_pointer(br->ip4_querier.port, port);
1103 
1104 	return true;
1105 }
1106 
1107 #if IS_ENABLED(CONFIG_IPV6)
1108 static bool br_ip6_multicast_select_querier(struct net_bridge *br,
1109 					    struct net_bridge_port *port,
1110 					    struct in6_addr *saddr)
1111 {
1112 	if (!timer_pending(&br->ip6_own_query.timer) &&
1113 	    !timer_pending(&br->ip6_other_query.timer))
1114 		goto update;
1115 
1116 	if (ipv6_addr_cmp(saddr, &br->ip6_querier.addr.u.ip6) <= 0)
1117 		goto update;
1118 
1119 	return false;
1120 
1121 update:
1122 	br->ip6_querier.addr.u.ip6 = *saddr;
1123 
1124 	/* update protected by general multicast_lock by caller */
1125 	rcu_assign_pointer(br->ip6_querier.port, port);
1126 
1127 	return true;
1128 }
1129 #endif
1130 
1131 static bool br_multicast_select_querier(struct net_bridge *br,
1132 					struct net_bridge_port *port,
1133 					struct br_ip *saddr)
1134 {
1135 	switch (saddr->proto) {
1136 	case htons(ETH_P_IP):
1137 		return br_ip4_multicast_select_querier(br, port, saddr->u.ip4);
1138 #if IS_ENABLED(CONFIG_IPV6)
1139 	case htons(ETH_P_IPV6):
1140 		return br_ip6_multicast_select_querier(br, port, &saddr->u.ip6);
1141 #endif
1142 	}
1143 
1144 	return false;
1145 }
1146 
1147 static void
1148 br_multicast_update_query_timer(struct net_bridge *br,
1149 				struct bridge_mcast_other_query *query,
1150 				unsigned long max_delay)
1151 {
1152 	if (!timer_pending(&query->timer))
1153 		query->delay_time = jiffies + max_delay;
1154 
1155 	mod_timer(&query->timer, jiffies + br->multicast_querier_interval);
1156 }
1157 
1158 /*
1159  * Add port to router_list
1160  *  list is maintained ordered by pointer value
1161  *  and locked by br->multicast_lock and RCU
1162  */
1163 static void br_multicast_add_router(struct net_bridge *br,
1164 				    struct net_bridge_port *port)
1165 {
1166 	struct net_bridge_port *p;
1167 	struct hlist_node *slot = NULL;
1168 
1169 	hlist_for_each_entry(p, &br->router_list, rlist) {
1170 		if ((unsigned long) port >= (unsigned long) p)
1171 			break;
1172 		slot = &p->rlist;
1173 	}
1174 
1175 	if (slot)
1176 		hlist_add_behind_rcu(&port->rlist, slot);
1177 	else
1178 		hlist_add_head_rcu(&port->rlist, &br->router_list);
1179 }
1180 
1181 static void br_multicast_mark_router(struct net_bridge *br,
1182 				     struct net_bridge_port *port)
1183 {
1184 	unsigned long now = jiffies;
1185 
1186 	if (!port) {
1187 		if (br->multicast_router == 1)
1188 			mod_timer(&br->multicast_router_timer,
1189 				  now + br->multicast_querier_interval);
1190 		return;
1191 	}
1192 
1193 	if (port->multicast_router != 1)
1194 		return;
1195 
1196 	if (!hlist_unhashed(&port->rlist))
1197 		goto timer;
1198 
1199 	br_multicast_add_router(br, port);
1200 
1201 timer:
1202 	mod_timer(&port->multicast_router_timer,
1203 		  now + br->multicast_querier_interval);
1204 }
1205 
1206 static void br_multicast_query_received(struct net_bridge *br,
1207 					struct net_bridge_port *port,
1208 					struct bridge_mcast_other_query *query,
1209 					struct br_ip *saddr,
1210 					unsigned long max_delay)
1211 {
1212 	if (!br_multicast_select_querier(br, port, saddr))
1213 		return;
1214 
1215 	br_multicast_update_query_timer(br, query, max_delay);
1216 	br_multicast_mark_router(br, port);
1217 }
1218 
1219 static int br_ip4_multicast_query(struct net_bridge *br,
1220 				  struct net_bridge_port *port,
1221 				  struct sk_buff *skb,
1222 				  u16 vid)
1223 {
1224 	const struct iphdr *iph = ip_hdr(skb);
1225 	struct igmphdr *ih = igmp_hdr(skb);
1226 	struct net_bridge_mdb_entry *mp;
1227 	struct igmpv3_query *ih3;
1228 	struct net_bridge_port_group *p;
1229 	struct net_bridge_port_group __rcu **pp;
1230 	struct br_ip saddr;
1231 	unsigned long max_delay;
1232 	unsigned long now = jiffies;
1233 	__be32 group;
1234 	int err = 0;
1235 
1236 	spin_lock(&br->multicast_lock);
1237 	if (!netif_running(br->dev) ||
1238 	    (port && port->state == BR_STATE_DISABLED))
1239 		goto out;
1240 
1241 	group = ih->group;
1242 
1243 	if (skb->len == sizeof(*ih)) {
1244 		max_delay = ih->code * (HZ / IGMP_TIMER_SCALE);
1245 
1246 		if (!max_delay) {
1247 			max_delay = 10 * HZ;
1248 			group = 0;
1249 		}
1250 	} else {
1251 		if (!pskb_may_pull(skb, sizeof(struct igmpv3_query))) {
1252 			err = -EINVAL;
1253 			goto out;
1254 		}
1255 
1256 		ih3 = igmpv3_query_hdr(skb);
1257 		if (ih3->nsrcs)
1258 			goto out;
1259 
1260 		max_delay = ih3->code ?
1261 			    IGMPV3_MRC(ih3->code) * (HZ / IGMP_TIMER_SCALE) : 1;
1262 	}
1263 
1264 	/* RFC2236+RFC3376 (IGMPv2+IGMPv3) require the multicast link layer
1265 	 * all-systems destination addresses (224.0.0.1) for general queries
1266 	 */
1267 	if (!group && iph->daddr != htonl(INADDR_ALLHOSTS_GROUP)) {
1268 		err = -EINVAL;
1269 		goto out;
1270 	}
1271 
1272 	if (!group) {
1273 		saddr.proto = htons(ETH_P_IP);
1274 		saddr.u.ip4 = iph->saddr;
1275 
1276 		br_multicast_query_received(br, port, &br->ip4_other_query,
1277 					    &saddr, max_delay);
1278 		goto out;
1279 	}
1280 
1281 	mp = br_mdb_ip4_get(mlock_dereference(br->mdb, br), group, vid);
1282 	if (!mp)
1283 		goto out;
1284 
1285 	max_delay *= br->multicast_last_member_count;
1286 
1287 	if (mp->mglist &&
1288 	    (timer_pending(&mp->timer) ?
1289 	     time_after(mp->timer.expires, now + max_delay) :
1290 	     try_to_del_timer_sync(&mp->timer) >= 0))
1291 		mod_timer(&mp->timer, now + max_delay);
1292 
1293 	for (pp = &mp->ports;
1294 	     (p = mlock_dereference(*pp, br)) != NULL;
1295 	     pp = &p->next) {
1296 		if (timer_pending(&p->timer) ?
1297 		    time_after(p->timer.expires, now + max_delay) :
1298 		    try_to_del_timer_sync(&p->timer) >= 0)
1299 			mod_timer(&p->timer, now + max_delay);
1300 	}
1301 
1302 out:
1303 	spin_unlock(&br->multicast_lock);
1304 	return err;
1305 }
1306 
1307 #if IS_ENABLED(CONFIG_IPV6)
1308 static int br_ip6_multicast_query(struct net_bridge *br,
1309 				  struct net_bridge_port *port,
1310 				  struct sk_buff *skb,
1311 				  u16 vid)
1312 {
1313 	const struct ipv6hdr *ip6h = ipv6_hdr(skb);
1314 	struct mld_msg *mld;
1315 	struct net_bridge_mdb_entry *mp;
1316 	struct mld2_query *mld2q;
1317 	struct net_bridge_port_group *p;
1318 	struct net_bridge_port_group __rcu **pp;
1319 	struct br_ip saddr;
1320 	unsigned long max_delay;
1321 	unsigned long now = jiffies;
1322 	const struct in6_addr *group = NULL;
1323 	bool is_general_query;
1324 	int err = 0;
1325 
1326 	spin_lock(&br->multicast_lock);
1327 	if (!netif_running(br->dev) ||
1328 	    (port && port->state == BR_STATE_DISABLED))
1329 		goto out;
1330 
1331 	/* RFC2710+RFC3810 (MLDv1+MLDv2) require link-local source addresses */
1332 	if (!(ipv6_addr_type(&ip6h->saddr) & IPV6_ADDR_LINKLOCAL)) {
1333 		err = -EINVAL;
1334 		goto out;
1335 	}
1336 
1337 	if (skb->len == sizeof(*mld)) {
1338 		if (!pskb_may_pull(skb, sizeof(*mld))) {
1339 			err = -EINVAL;
1340 			goto out;
1341 		}
1342 		mld = (struct mld_msg *) icmp6_hdr(skb);
1343 		max_delay = msecs_to_jiffies(ntohs(mld->mld_maxdelay));
1344 		if (max_delay)
1345 			group = &mld->mld_mca;
1346 	} else {
1347 		if (!pskb_may_pull(skb, sizeof(*mld2q))) {
1348 			err = -EINVAL;
1349 			goto out;
1350 		}
1351 		mld2q = (struct mld2_query *)icmp6_hdr(skb);
1352 		if (!mld2q->mld2q_nsrcs)
1353 			group = &mld2q->mld2q_mca;
1354 
1355 		max_delay = max(msecs_to_jiffies(mldv2_mrc(mld2q)), 1UL);
1356 	}
1357 
1358 	is_general_query = group && ipv6_addr_any(group);
1359 
1360 	/* RFC2710+RFC3810 (MLDv1+MLDv2) require the multicast link layer
1361 	 * all-nodes destination address (ff02::1) for general queries
1362 	 */
1363 	if (is_general_query && !ipv6_addr_is_ll_all_nodes(&ip6h->daddr)) {
1364 		err = -EINVAL;
1365 		goto out;
1366 	}
1367 
1368 	if (is_general_query) {
1369 		saddr.proto = htons(ETH_P_IPV6);
1370 		saddr.u.ip6 = ip6h->saddr;
1371 
1372 		br_multicast_query_received(br, port, &br->ip6_other_query,
1373 					    &saddr, max_delay);
1374 		goto out;
1375 	} else if (!group) {
1376 		goto out;
1377 	}
1378 
1379 	mp = br_mdb_ip6_get(mlock_dereference(br->mdb, br), group, vid);
1380 	if (!mp)
1381 		goto out;
1382 
1383 	max_delay *= br->multicast_last_member_count;
1384 	if (mp->mglist &&
1385 	    (timer_pending(&mp->timer) ?
1386 	     time_after(mp->timer.expires, now + max_delay) :
1387 	     try_to_del_timer_sync(&mp->timer) >= 0))
1388 		mod_timer(&mp->timer, now + max_delay);
1389 
1390 	for (pp = &mp->ports;
1391 	     (p = mlock_dereference(*pp, br)) != NULL;
1392 	     pp = &p->next) {
1393 		if (timer_pending(&p->timer) ?
1394 		    time_after(p->timer.expires, now + max_delay) :
1395 		    try_to_del_timer_sync(&p->timer) >= 0)
1396 			mod_timer(&p->timer, now + max_delay);
1397 	}
1398 
1399 out:
1400 	spin_unlock(&br->multicast_lock);
1401 	return err;
1402 }
1403 #endif
1404 
1405 static void
1406 br_multicast_leave_group(struct net_bridge *br,
1407 			 struct net_bridge_port *port,
1408 			 struct br_ip *group,
1409 			 struct bridge_mcast_other_query *other_query,
1410 			 struct bridge_mcast_own_query *own_query)
1411 {
1412 	struct net_bridge_mdb_htable *mdb;
1413 	struct net_bridge_mdb_entry *mp;
1414 	struct net_bridge_port_group *p;
1415 	unsigned long now;
1416 	unsigned long time;
1417 
1418 	spin_lock(&br->multicast_lock);
1419 	if (!netif_running(br->dev) ||
1420 	    (port && port->state == BR_STATE_DISABLED) ||
1421 	    timer_pending(&other_query->timer))
1422 		goto out;
1423 
1424 	mdb = mlock_dereference(br->mdb, br);
1425 	mp = br_mdb_ip_get(mdb, group);
1426 	if (!mp)
1427 		goto out;
1428 
1429 	if (br->multicast_querier) {
1430 		__br_multicast_send_query(br, port, &mp->addr);
1431 
1432 		time = jiffies + br->multicast_last_member_count *
1433 				 br->multicast_last_member_interval;
1434 
1435 		mod_timer(&own_query->timer, time);
1436 
1437 		for (p = mlock_dereference(mp->ports, br);
1438 		     p != NULL;
1439 		     p = mlock_dereference(p->next, br)) {
1440 			if (p->port != port)
1441 				continue;
1442 
1443 			if (!hlist_unhashed(&p->mglist) &&
1444 			    (timer_pending(&p->timer) ?
1445 			     time_after(p->timer.expires, time) :
1446 			     try_to_del_timer_sync(&p->timer) >= 0)) {
1447 				mod_timer(&p->timer, time);
1448 			}
1449 
1450 			break;
1451 		}
1452 	}
1453 
1454 	if (port && (port->flags & BR_MULTICAST_FAST_LEAVE)) {
1455 		struct net_bridge_port_group __rcu **pp;
1456 
1457 		for (pp = &mp->ports;
1458 		     (p = mlock_dereference(*pp, br)) != NULL;
1459 		     pp = &p->next) {
1460 			if (p->port != port)
1461 				continue;
1462 
1463 			rcu_assign_pointer(*pp, p->next);
1464 			hlist_del_init(&p->mglist);
1465 			del_timer(&p->timer);
1466 			call_rcu_bh(&p->rcu, br_multicast_free_pg);
1467 			br_mdb_notify(br->dev, port, group, RTM_DELMDB);
1468 
1469 			if (!mp->ports && !mp->mglist &&
1470 			    netif_running(br->dev))
1471 				mod_timer(&mp->timer, jiffies);
1472 		}
1473 		goto out;
1474 	}
1475 
1476 	now = jiffies;
1477 	time = now + br->multicast_last_member_count *
1478 		     br->multicast_last_member_interval;
1479 
1480 	if (!port) {
1481 		if (mp->mglist &&
1482 		    (timer_pending(&mp->timer) ?
1483 		     time_after(mp->timer.expires, time) :
1484 		     try_to_del_timer_sync(&mp->timer) >= 0)) {
1485 			mod_timer(&mp->timer, time);
1486 		}
1487 
1488 		goto out;
1489 	}
1490 
1491 	for (p = mlock_dereference(mp->ports, br);
1492 	     p != NULL;
1493 	     p = mlock_dereference(p->next, br)) {
1494 		if (p->port != port)
1495 			continue;
1496 
1497 		if (!hlist_unhashed(&p->mglist) &&
1498 		    (timer_pending(&p->timer) ?
1499 		     time_after(p->timer.expires, time) :
1500 		     try_to_del_timer_sync(&p->timer) >= 0)) {
1501 			mod_timer(&p->timer, time);
1502 		}
1503 
1504 		break;
1505 	}
1506 out:
1507 	spin_unlock(&br->multicast_lock);
1508 }
1509 
1510 static void br_ip4_multicast_leave_group(struct net_bridge *br,
1511 					 struct net_bridge_port *port,
1512 					 __be32 group,
1513 					 __u16 vid)
1514 {
1515 	struct br_ip br_group;
1516 	struct bridge_mcast_own_query *own_query;
1517 
1518 	if (ipv4_is_local_multicast(group))
1519 		return;
1520 
1521 	own_query = port ? &port->ip4_own_query : &br->ip4_own_query;
1522 
1523 	br_group.u.ip4 = group;
1524 	br_group.proto = htons(ETH_P_IP);
1525 	br_group.vid = vid;
1526 
1527 	br_multicast_leave_group(br, port, &br_group, &br->ip4_other_query,
1528 				 own_query);
1529 }
1530 
1531 #if IS_ENABLED(CONFIG_IPV6)
1532 static void br_ip6_multicast_leave_group(struct net_bridge *br,
1533 					 struct net_bridge_port *port,
1534 					 const struct in6_addr *group,
1535 					 __u16 vid)
1536 {
1537 	struct br_ip br_group;
1538 	struct bridge_mcast_own_query *own_query;
1539 
1540 	if (ipv6_addr_is_ll_all_nodes(group))
1541 		return;
1542 
1543 	own_query = port ? &port->ip6_own_query : &br->ip6_own_query;
1544 
1545 	br_group.u.ip6 = *group;
1546 	br_group.proto = htons(ETH_P_IPV6);
1547 	br_group.vid = vid;
1548 
1549 	br_multicast_leave_group(br, port, &br_group, &br->ip6_other_query,
1550 				 own_query);
1551 }
1552 #endif
1553 
1554 static int br_multicast_ipv4_rcv(struct net_bridge *br,
1555 				 struct net_bridge_port *port,
1556 				 struct sk_buff *skb,
1557 				 u16 vid)
1558 {
1559 	struct sk_buff *skb2 = skb;
1560 	const struct iphdr *iph;
1561 	struct igmphdr *ih;
1562 	unsigned int len;
1563 	unsigned int offset;
1564 	int err;
1565 
1566 	/* We treat OOM as packet loss for now. */
1567 	if (!pskb_may_pull(skb, sizeof(*iph)))
1568 		return -EINVAL;
1569 
1570 	iph = ip_hdr(skb);
1571 
1572 	if (iph->ihl < 5 || iph->version != 4)
1573 		return -EINVAL;
1574 
1575 	if (!pskb_may_pull(skb, ip_hdrlen(skb)))
1576 		return -EINVAL;
1577 
1578 	iph = ip_hdr(skb);
1579 
1580 	if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1581 		return -EINVAL;
1582 
1583 	if (iph->protocol != IPPROTO_IGMP) {
1584 		if (!ipv4_is_local_multicast(iph->daddr))
1585 			BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1586 		return 0;
1587 	}
1588 
1589 	len = ntohs(iph->tot_len);
1590 	if (skb->len < len || len < ip_hdrlen(skb))
1591 		return -EINVAL;
1592 
1593 	if (skb->len > len) {
1594 		skb2 = skb_clone(skb, GFP_ATOMIC);
1595 		if (!skb2)
1596 			return -ENOMEM;
1597 
1598 		err = pskb_trim_rcsum(skb2, len);
1599 		if (err)
1600 			goto err_out;
1601 	}
1602 
1603 	len -= ip_hdrlen(skb2);
1604 	offset = skb_network_offset(skb2) + ip_hdrlen(skb2);
1605 	__skb_pull(skb2, offset);
1606 	skb_reset_transport_header(skb2);
1607 
1608 	err = -EINVAL;
1609 	if (!pskb_may_pull(skb2, sizeof(*ih)))
1610 		goto out;
1611 
1612 	switch (skb2->ip_summed) {
1613 	case CHECKSUM_COMPLETE:
1614 		if (!csum_fold(skb2->csum))
1615 			break;
1616 		/* fall through */
1617 	case CHECKSUM_NONE:
1618 		skb2->csum = 0;
1619 		if (skb_checksum_complete(skb2))
1620 			goto out;
1621 	}
1622 
1623 	err = 0;
1624 
1625 	BR_INPUT_SKB_CB(skb)->igmp = 1;
1626 	ih = igmp_hdr(skb2);
1627 
1628 	switch (ih->type) {
1629 	case IGMP_HOST_MEMBERSHIP_REPORT:
1630 	case IGMPV2_HOST_MEMBERSHIP_REPORT:
1631 		BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1632 		err = br_ip4_multicast_add_group(br, port, ih->group, vid);
1633 		break;
1634 	case IGMPV3_HOST_MEMBERSHIP_REPORT:
1635 		err = br_ip4_multicast_igmp3_report(br, port, skb2, vid);
1636 		break;
1637 	case IGMP_HOST_MEMBERSHIP_QUERY:
1638 		err = br_ip4_multicast_query(br, port, skb2, vid);
1639 		break;
1640 	case IGMP_HOST_LEAVE_MESSAGE:
1641 		br_ip4_multicast_leave_group(br, port, ih->group, vid);
1642 		break;
1643 	}
1644 
1645 out:
1646 	__skb_push(skb2, offset);
1647 err_out:
1648 	if (skb2 != skb)
1649 		kfree_skb(skb2);
1650 	return err;
1651 }
1652 
1653 #if IS_ENABLED(CONFIG_IPV6)
1654 static int br_multicast_ipv6_rcv(struct net_bridge *br,
1655 				 struct net_bridge_port *port,
1656 				 struct sk_buff *skb,
1657 				 u16 vid)
1658 {
1659 	struct sk_buff *skb2;
1660 	const struct ipv6hdr *ip6h;
1661 	u8 icmp6_type;
1662 	u8 nexthdr;
1663 	__be16 frag_off;
1664 	unsigned int len;
1665 	int offset;
1666 	int err;
1667 
1668 	if (!pskb_may_pull(skb, sizeof(*ip6h)))
1669 		return -EINVAL;
1670 
1671 	ip6h = ipv6_hdr(skb);
1672 
1673 	/*
1674 	 * We're interested in MLD messages only.
1675 	 *  - Version is 6
1676 	 *  - MLD has always Router Alert hop-by-hop option
1677 	 *  - But we do not support jumbrograms.
1678 	 */
1679 	if (ip6h->version != 6)
1680 		return 0;
1681 
1682 	/* Prevent flooding this packet if there is no listener present */
1683 	if (!ipv6_addr_is_ll_all_nodes(&ip6h->daddr))
1684 		BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1685 
1686 	if (ip6h->nexthdr != IPPROTO_HOPOPTS ||
1687 	    ip6h->payload_len == 0)
1688 		return 0;
1689 
1690 	len = ntohs(ip6h->payload_len) + sizeof(*ip6h);
1691 	if (skb->len < len)
1692 		return -EINVAL;
1693 
1694 	nexthdr = ip6h->nexthdr;
1695 	offset = ipv6_skip_exthdr(skb, sizeof(*ip6h), &nexthdr, &frag_off);
1696 
1697 	if (offset < 0 || nexthdr != IPPROTO_ICMPV6)
1698 		return 0;
1699 
1700 	/* Okay, we found ICMPv6 header */
1701 	skb2 = skb_clone(skb, GFP_ATOMIC);
1702 	if (!skb2)
1703 		return -ENOMEM;
1704 
1705 	err = -EINVAL;
1706 	if (!pskb_may_pull(skb2, offset + sizeof(struct icmp6hdr)))
1707 		goto out;
1708 
1709 	len -= offset - skb_network_offset(skb2);
1710 
1711 	__skb_pull(skb2, offset);
1712 	skb_reset_transport_header(skb2);
1713 	skb_postpull_rcsum(skb2, skb_network_header(skb2),
1714 			   skb_network_header_len(skb2));
1715 
1716 	icmp6_type = icmp6_hdr(skb2)->icmp6_type;
1717 
1718 	switch (icmp6_type) {
1719 	case ICMPV6_MGM_QUERY:
1720 	case ICMPV6_MGM_REPORT:
1721 	case ICMPV6_MGM_REDUCTION:
1722 	case ICMPV6_MLD2_REPORT:
1723 		break;
1724 	default:
1725 		err = 0;
1726 		goto out;
1727 	}
1728 
1729 	/* Okay, we found MLD message. Check further. */
1730 	if (skb2->len > len) {
1731 		err = pskb_trim_rcsum(skb2, len);
1732 		if (err)
1733 			goto out;
1734 		err = -EINVAL;
1735 	}
1736 
1737 	ip6h = ipv6_hdr(skb2);
1738 
1739 	switch (skb2->ip_summed) {
1740 	case CHECKSUM_COMPLETE:
1741 		if (!csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, skb2->len,
1742 					IPPROTO_ICMPV6, skb2->csum))
1743 			break;
1744 		/*FALLTHROUGH*/
1745 	case CHECKSUM_NONE:
1746 		skb2->csum = ~csum_unfold(csum_ipv6_magic(&ip6h->saddr,
1747 							&ip6h->daddr,
1748 							skb2->len,
1749 							IPPROTO_ICMPV6, 0));
1750 		if (__skb_checksum_complete(skb2))
1751 			goto out;
1752 	}
1753 
1754 	err = 0;
1755 
1756 	BR_INPUT_SKB_CB(skb)->igmp = 1;
1757 
1758 	switch (icmp6_type) {
1759 	case ICMPV6_MGM_REPORT:
1760 	    {
1761 		struct mld_msg *mld;
1762 		if (!pskb_may_pull(skb2, sizeof(*mld))) {
1763 			err = -EINVAL;
1764 			goto out;
1765 		}
1766 		mld = (struct mld_msg *)skb_transport_header(skb2);
1767 		BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1768 		err = br_ip6_multicast_add_group(br, port, &mld->mld_mca, vid);
1769 		break;
1770 	    }
1771 	case ICMPV6_MLD2_REPORT:
1772 		err = br_ip6_multicast_mld2_report(br, port, skb2, vid);
1773 		break;
1774 	case ICMPV6_MGM_QUERY:
1775 		err = br_ip6_multicast_query(br, port, skb2, vid);
1776 		break;
1777 	case ICMPV6_MGM_REDUCTION:
1778 	    {
1779 		struct mld_msg *mld;
1780 		if (!pskb_may_pull(skb2, sizeof(*mld))) {
1781 			err = -EINVAL;
1782 			goto out;
1783 		}
1784 		mld = (struct mld_msg *)skb_transport_header(skb2);
1785 		br_ip6_multicast_leave_group(br, port, &mld->mld_mca, vid);
1786 	    }
1787 	}
1788 
1789 out:
1790 	kfree_skb(skb2);
1791 	return err;
1792 }
1793 #endif
1794 
1795 int br_multicast_rcv(struct net_bridge *br, struct net_bridge_port *port,
1796 		     struct sk_buff *skb, u16 vid)
1797 {
1798 	BR_INPUT_SKB_CB(skb)->igmp = 0;
1799 	BR_INPUT_SKB_CB(skb)->mrouters_only = 0;
1800 
1801 	if (br->multicast_disabled)
1802 		return 0;
1803 
1804 	switch (skb->protocol) {
1805 	case htons(ETH_P_IP):
1806 		return br_multicast_ipv4_rcv(br, port, skb, vid);
1807 #if IS_ENABLED(CONFIG_IPV6)
1808 	case htons(ETH_P_IPV6):
1809 		return br_multicast_ipv6_rcv(br, port, skb, vid);
1810 #endif
1811 	}
1812 
1813 	return 0;
1814 }
1815 
1816 static void br_multicast_query_expired(struct net_bridge *br,
1817 				       struct bridge_mcast_own_query *query,
1818 				       struct bridge_mcast_querier *querier)
1819 {
1820 	spin_lock(&br->multicast_lock);
1821 	if (query->startup_sent < br->multicast_startup_query_count)
1822 		query->startup_sent++;
1823 
1824 	RCU_INIT_POINTER(querier, NULL);
1825 	br_multicast_send_query(br, NULL, query);
1826 	spin_unlock(&br->multicast_lock);
1827 }
1828 
1829 static void br_ip4_multicast_query_expired(unsigned long data)
1830 {
1831 	struct net_bridge *br = (void *)data;
1832 
1833 	br_multicast_query_expired(br, &br->ip4_own_query, &br->ip4_querier);
1834 }
1835 
1836 #if IS_ENABLED(CONFIG_IPV6)
1837 static void br_ip6_multicast_query_expired(unsigned long data)
1838 {
1839 	struct net_bridge *br = (void *)data;
1840 
1841 	br_multicast_query_expired(br, &br->ip6_own_query, &br->ip6_querier);
1842 }
1843 #endif
1844 
1845 void br_multicast_init(struct net_bridge *br)
1846 {
1847 	br->hash_elasticity = 4;
1848 	br->hash_max = 512;
1849 
1850 	br->multicast_router = 1;
1851 	br->multicast_querier = 0;
1852 	br->multicast_query_use_ifaddr = 0;
1853 	br->multicast_last_member_count = 2;
1854 	br->multicast_startup_query_count = 2;
1855 
1856 	br->multicast_last_member_interval = HZ;
1857 	br->multicast_query_response_interval = 10 * HZ;
1858 	br->multicast_startup_query_interval = 125 * HZ / 4;
1859 	br->multicast_query_interval = 125 * HZ;
1860 	br->multicast_querier_interval = 255 * HZ;
1861 	br->multicast_membership_interval = 260 * HZ;
1862 
1863 	br->ip4_other_query.delay_time = 0;
1864 	br->ip4_querier.port = NULL;
1865 #if IS_ENABLED(CONFIG_IPV6)
1866 	br->ip6_other_query.delay_time = 0;
1867 	br->ip6_querier.port = NULL;
1868 #endif
1869 
1870 	spin_lock_init(&br->multicast_lock);
1871 	setup_timer(&br->multicast_router_timer,
1872 		    br_multicast_local_router_expired, 0);
1873 	setup_timer(&br->ip4_other_query.timer,
1874 		    br_ip4_multicast_querier_expired, (unsigned long)br);
1875 	setup_timer(&br->ip4_own_query.timer, br_ip4_multicast_query_expired,
1876 		    (unsigned long)br);
1877 #if IS_ENABLED(CONFIG_IPV6)
1878 	setup_timer(&br->ip6_other_query.timer,
1879 		    br_ip6_multicast_querier_expired, (unsigned long)br);
1880 	setup_timer(&br->ip6_own_query.timer, br_ip6_multicast_query_expired,
1881 		    (unsigned long)br);
1882 #endif
1883 }
1884 
1885 static void __br_multicast_open(struct net_bridge *br,
1886 				struct bridge_mcast_own_query *query)
1887 {
1888 	query->startup_sent = 0;
1889 
1890 	if (br->multicast_disabled)
1891 		return;
1892 
1893 	mod_timer(&query->timer, jiffies);
1894 }
1895 
1896 void br_multicast_open(struct net_bridge *br)
1897 {
1898 	__br_multicast_open(br, &br->ip4_own_query);
1899 #if IS_ENABLED(CONFIG_IPV6)
1900 	__br_multicast_open(br, &br->ip6_own_query);
1901 #endif
1902 }
1903 
1904 void br_multicast_stop(struct net_bridge *br)
1905 {
1906 	struct net_bridge_mdb_htable *mdb;
1907 	struct net_bridge_mdb_entry *mp;
1908 	struct hlist_node *n;
1909 	u32 ver;
1910 	int i;
1911 
1912 	del_timer_sync(&br->multicast_router_timer);
1913 	del_timer_sync(&br->ip4_other_query.timer);
1914 	del_timer_sync(&br->ip4_own_query.timer);
1915 #if IS_ENABLED(CONFIG_IPV6)
1916 	del_timer_sync(&br->ip6_other_query.timer);
1917 	del_timer_sync(&br->ip6_own_query.timer);
1918 #endif
1919 
1920 	spin_lock_bh(&br->multicast_lock);
1921 	mdb = mlock_dereference(br->mdb, br);
1922 	if (!mdb)
1923 		goto out;
1924 
1925 	br->mdb = NULL;
1926 
1927 	ver = mdb->ver;
1928 	for (i = 0; i < mdb->max; i++) {
1929 		hlist_for_each_entry_safe(mp, n, &mdb->mhash[i],
1930 					  hlist[ver]) {
1931 			del_timer(&mp->timer);
1932 			call_rcu_bh(&mp->rcu, br_multicast_free_group);
1933 		}
1934 	}
1935 
1936 	if (mdb->old) {
1937 		spin_unlock_bh(&br->multicast_lock);
1938 		rcu_barrier_bh();
1939 		spin_lock_bh(&br->multicast_lock);
1940 		WARN_ON(mdb->old);
1941 	}
1942 
1943 	mdb->old = mdb;
1944 	call_rcu_bh(&mdb->rcu, br_mdb_free);
1945 
1946 out:
1947 	spin_unlock_bh(&br->multicast_lock);
1948 }
1949 
1950 int br_multicast_set_router(struct net_bridge *br, unsigned long val)
1951 {
1952 	int err = -ENOENT;
1953 
1954 	spin_lock_bh(&br->multicast_lock);
1955 	if (!netif_running(br->dev))
1956 		goto unlock;
1957 
1958 	switch (val) {
1959 	case 0:
1960 	case 2:
1961 		del_timer(&br->multicast_router_timer);
1962 		/* fall through */
1963 	case 1:
1964 		br->multicast_router = val;
1965 		err = 0;
1966 		break;
1967 
1968 	default:
1969 		err = -EINVAL;
1970 		break;
1971 	}
1972 
1973 unlock:
1974 	spin_unlock_bh(&br->multicast_lock);
1975 
1976 	return err;
1977 }
1978 
1979 int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
1980 {
1981 	struct net_bridge *br = p->br;
1982 	int err = -ENOENT;
1983 
1984 	spin_lock(&br->multicast_lock);
1985 	if (!netif_running(br->dev) || p->state == BR_STATE_DISABLED)
1986 		goto unlock;
1987 
1988 	switch (val) {
1989 	case 0:
1990 	case 1:
1991 	case 2:
1992 		p->multicast_router = val;
1993 		err = 0;
1994 
1995 		if (val < 2 && !hlist_unhashed(&p->rlist))
1996 			hlist_del_init_rcu(&p->rlist);
1997 
1998 		if (val == 1)
1999 			break;
2000 
2001 		del_timer(&p->multicast_router_timer);
2002 
2003 		if (val == 0)
2004 			break;
2005 
2006 		br_multicast_add_router(br, p);
2007 		break;
2008 
2009 	default:
2010 		err = -EINVAL;
2011 		break;
2012 	}
2013 
2014 unlock:
2015 	spin_unlock(&br->multicast_lock);
2016 
2017 	return err;
2018 }
2019 
2020 static void br_multicast_start_querier(struct net_bridge *br,
2021 				       struct bridge_mcast_own_query *query)
2022 {
2023 	struct net_bridge_port *port;
2024 
2025 	__br_multicast_open(br, query);
2026 
2027 	list_for_each_entry(port, &br->port_list, list) {
2028 		if (port->state == BR_STATE_DISABLED ||
2029 		    port->state == BR_STATE_BLOCKING)
2030 			continue;
2031 
2032 		if (query == &br->ip4_own_query)
2033 			br_multicast_enable(&port->ip4_own_query);
2034 #if IS_ENABLED(CONFIG_IPV6)
2035 		else
2036 			br_multicast_enable(&port->ip6_own_query);
2037 #endif
2038 	}
2039 }
2040 
2041 int br_multicast_toggle(struct net_bridge *br, unsigned long val)
2042 {
2043 	int err = 0;
2044 	struct net_bridge_mdb_htable *mdb;
2045 
2046 	spin_lock_bh(&br->multicast_lock);
2047 	if (br->multicast_disabled == !val)
2048 		goto unlock;
2049 
2050 	br->multicast_disabled = !val;
2051 	if (br->multicast_disabled)
2052 		goto unlock;
2053 
2054 	if (!netif_running(br->dev))
2055 		goto unlock;
2056 
2057 	mdb = mlock_dereference(br->mdb, br);
2058 	if (mdb) {
2059 		if (mdb->old) {
2060 			err = -EEXIST;
2061 rollback:
2062 			br->multicast_disabled = !!val;
2063 			goto unlock;
2064 		}
2065 
2066 		err = br_mdb_rehash(&br->mdb, mdb->max,
2067 				    br->hash_elasticity);
2068 		if (err)
2069 			goto rollback;
2070 	}
2071 
2072 	br_multicast_start_querier(br, &br->ip4_own_query);
2073 #if IS_ENABLED(CONFIG_IPV6)
2074 	br_multicast_start_querier(br, &br->ip6_own_query);
2075 #endif
2076 
2077 unlock:
2078 	spin_unlock_bh(&br->multicast_lock);
2079 
2080 	return err;
2081 }
2082 
2083 int br_multicast_set_querier(struct net_bridge *br, unsigned long val)
2084 {
2085 	unsigned long max_delay;
2086 
2087 	val = !!val;
2088 
2089 	spin_lock_bh(&br->multicast_lock);
2090 	if (br->multicast_querier == val)
2091 		goto unlock;
2092 
2093 	br->multicast_querier = val;
2094 	if (!val)
2095 		goto unlock;
2096 
2097 	max_delay = br->multicast_query_response_interval;
2098 
2099 	if (!timer_pending(&br->ip4_other_query.timer))
2100 		br->ip4_other_query.delay_time = jiffies + max_delay;
2101 
2102 	br_multicast_start_querier(br, &br->ip4_own_query);
2103 
2104 #if IS_ENABLED(CONFIG_IPV6)
2105 	if (!timer_pending(&br->ip6_other_query.timer))
2106 		br->ip6_other_query.delay_time = jiffies + max_delay;
2107 
2108 	br_multicast_start_querier(br, &br->ip6_own_query);
2109 #endif
2110 
2111 unlock:
2112 	spin_unlock_bh(&br->multicast_lock);
2113 
2114 	return 0;
2115 }
2116 
2117 int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val)
2118 {
2119 	int err = -ENOENT;
2120 	u32 old;
2121 	struct net_bridge_mdb_htable *mdb;
2122 
2123 	spin_lock_bh(&br->multicast_lock);
2124 	if (!netif_running(br->dev))
2125 		goto unlock;
2126 
2127 	err = -EINVAL;
2128 	if (!is_power_of_2(val))
2129 		goto unlock;
2130 
2131 	mdb = mlock_dereference(br->mdb, br);
2132 	if (mdb && val < mdb->size)
2133 		goto unlock;
2134 
2135 	err = 0;
2136 
2137 	old = br->hash_max;
2138 	br->hash_max = val;
2139 
2140 	if (mdb) {
2141 		if (mdb->old) {
2142 			err = -EEXIST;
2143 rollback:
2144 			br->hash_max = old;
2145 			goto unlock;
2146 		}
2147 
2148 		err = br_mdb_rehash(&br->mdb, br->hash_max,
2149 				    br->hash_elasticity);
2150 		if (err)
2151 			goto rollback;
2152 	}
2153 
2154 unlock:
2155 	spin_unlock_bh(&br->multicast_lock);
2156 
2157 	return err;
2158 }
2159 
2160 /**
2161  * br_multicast_list_adjacent - Returns snooped multicast addresses
2162  * @dev:	The bridge port adjacent to which to retrieve addresses
2163  * @br_ip_list:	The list to store found, snooped multicast IP addresses in
2164  *
2165  * Creates a list of IP addresses (struct br_ip_list) sensed by the multicast
2166  * snooping feature on all bridge ports of dev's bridge device, excluding
2167  * the addresses from dev itself.
2168  *
2169  * Returns the number of items added to br_ip_list.
2170  *
2171  * Notes:
2172  * - br_ip_list needs to be initialized by caller
2173  * - br_ip_list might contain duplicates in the end
2174  *   (needs to be taken care of by caller)
2175  * - br_ip_list needs to be freed by caller
2176  */
2177 int br_multicast_list_adjacent(struct net_device *dev,
2178 			       struct list_head *br_ip_list)
2179 {
2180 	struct net_bridge *br;
2181 	struct net_bridge_port *port;
2182 	struct net_bridge_port_group *group;
2183 	struct br_ip_list *entry;
2184 	int count = 0;
2185 
2186 	rcu_read_lock();
2187 	if (!br_ip_list || !br_port_exists(dev))
2188 		goto unlock;
2189 
2190 	port = br_port_get_rcu(dev);
2191 	if (!port || !port->br)
2192 		goto unlock;
2193 
2194 	br = port->br;
2195 
2196 	list_for_each_entry_rcu(port, &br->port_list, list) {
2197 		if (!port->dev || port->dev == dev)
2198 			continue;
2199 
2200 		hlist_for_each_entry_rcu(group, &port->mglist, mglist) {
2201 			entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
2202 			if (!entry)
2203 				goto unlock;
2204 
2205 			entry->addr = group->addr;
2206 			list_add(&entry->list, br_ip_list);
2207 			count++;
2208 		}
2209 	}
2210 
2211 unlock:
2212 	rcu_read_unlock();
2213 	return count;
2214 }
2215 EXPORT_SYMBOL_GPL(br_multicast_list_adjacent);
2216 
2217 /**
2218  * br_multicast_has_querier_anywhere - Checks for a querier on a bridge
2219  * @dev: The bridge port providing the bridge on which to check for a querier
2220  * @proto: The protocol family to check for: IGMP -> ETH_P_IP, MLD -> ETH_P_IPV6
2221  *
2222  * Checks whether the given interface has a bridge on top and if so returns
2223  * true if a valid querier exists anywhere on the bridged link layer.
2224  * Otherwise returns false.
2225  */
2226 bool br_multicast_has_querier_anywhere(struct net_device *dev, int proto)
2227 {
2228 	struct net_bridge *br;
2229 	struct net_bridge_port *port;
2230 	struct ethhdr eth;
2231 	bool ret = false;
2232 
2233 	rcu_read_lock();
2234 	if (!br_port_exists(dev))
2235 		goto unlock;
2236 
2237 	port = br_port_get_rcu(dev);
2238 	if (!port || !port->br)
2239 		goto unlock;
2240 
2241 	br = port->br;
2242 
2243 	memset(&eth, 0, sizeof(eth));
2244 	eth.h_proto = htons(proto);
2245 
2246 	ret = br_multicast_querier_exists(br, &eth);
2247 
2248 unlock:
2249 	rcu_read_unlock();
2250 	return ret;
2251 }
2252 EXPORT_SYMBOL_GPL(br_multicast_has_querier_anywhere);
2253 
2254 /**
2255  * br_multicast_has_querier_adjacent - Checks for a querier behind a bridge port
2256  * @dev: The bridge port adjacent to which to check for a querier
2257  * @proto: The protocol family to check for: IGMP -> ETH_P_IP, MLD -> ETH_P_IPV6
2258  *
2259  * Checks whether the given interface has a bridge on top and if so returns
2260  * true if a selected querier is behind one of the other ports of this
2261  * bridge. Otherwise returns false.
2262  */
2263 bool br_multicast_has_querier_adjacent(struct net_device *dev, int proto)
2264 {
2265 	struct net_bridge *br;
2266 	struct net_bridge_port *port;
2267 	bool ret = false;
2268 
2269 	rcu_read_lock();
2270 	if (!br_port_exists(dev))
2271 		goto unlock;
2272 
2273 	port = br_port_get_rcu(dev);
2274 	if (!port || !port->br)
2275 		goto unlock;
2276 
2277 	br = port->br;
2278 
2279 	switch (proto) {
2280 	case ETH_P_IP:
2281 		if (!timer_pending(&br->ip4_other_query.timer) ||
2282 		    rcu_dereference(br->ip4_querier.port) == port)
2283 			goto unlock;
2284 		break;
2285 #if IS_ENABLED(CONFIG_IPV6)
2286 	case ETH_P_IPV6:
2287 		if (!timer_pending(&br->ip6_other_query.timer) ||
2288 		    rcu_dereference(br->ip6_querier.port) == port)
2289 			goto unlock;
2290 		break;
2291 #endif
2292 	default:
2293 		goto unlock;
2294 	}
2295 
2296 	ret = true;
2297 unlock:
2298 	rcu_read_unlock();
2299 	return ret;
2300 }
2301 EXPORT_SYMBOL_GPL(br_multicast_has_querier_adjacent);
2302