xref: /openbmc/linux/net/bridge/br_multicast.c (revision b34e08d5)
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/if_ether.h>
15 #include <linux/igmp.h>
16 #include <linux/jhash.h>
17 #include <linux/kernel.h>
18 #include <linux/log2.h>
19 #include <linux/netdevice.h>
20 #include <linux/netfilter_bridge.h>
21 #include <linux/random.h>
22 #include <linux/rculist.h>
23 #include <linux/skbuff.h>
24 #include <linux/slab.h>
25 #include <linux/timer.h>
26 #include <linux/inetdevice.h>
27 #include <net/ip.h>
28 #if IS_ENABLED(CONFIG_IPV6)
29 #include <net/ipv6.h>
30 #include <net/mld.h>
31 #include <net/ip6_checksum.h>
32 #include <net/addrconf.h>
33 #endif
34 
35 #include "br_private.h"
36 
37 static void br_multicast_start_querier(struct net_bridge *br,
38 				       struct bridge_mcast_query *query);
39 unsigned int br_mdb_rehash_seq;
40 
41 static inline int br_ip_equal(const struct br_ip *a, const struct br_ip *b)
42 {
43 	if (a->proto != b->proto)
44 		return 0;
45 	if (a->vid != b->vid)
46 		return 0;
47 	switch (a->proto) {
48 	case htons(ETH_P_IP):
49 		return a->u.ip4 == b->u.ip4;
50 #if IS_ENABLED(CONFIG_IPV6)
51 	case htons(ETH_P_IPV6):
52 		return ipv6_addr_equal(&a->u.ip6, &b->u.ip6);
53 #endif
54 	}
55 	return 0;
56 }
57 
58 static inline int __br_ip4_hash(struct net_bridge_mdb_htable *mdb, __be32 ip,
59 				__u16 vid)
60 {
61 	return jhash_2words((__force u32)ip, vid, mdb->secret) & (mdb->max - 1);
62 }
63 
64 #if IS_ENABLED(CONFIG_IPV6)
65 static inline int __br_ip6_hash(struct net_bridge_mdb_htable *mdb,
66 				const struct in6_addr *ip,
67 				__u16 vid)
68 {
69 	return jhash_2words(ipv6_addr_hash(ip), vid,
70 			    mdb->secret) & (mdb->max - 1);
71 }
72 #endif
73 
74 static inline int br_ip_hash(struct net_bridge_mdb_htable *mdb,
75 			     struct br_ip *ip)
76 {
77 	switch (ip->proto) {
78 	case htons(ETH_P_IP):
79 		return __br_ip4_hash(mdb, ip->u.ip4, ip->vid);
80 #if IS_ENABLED(CONFIG_IPV6)
81 	case htons(ETH_P_IPV6):
82 		return __br_ip6_hash(mdb, &ip->u.ip6, ip->vid);
83 #endif
84 	}
85 	return 0;
86 }
87 
88 static struct net_bridge_mdb_entry *__br_mdb_ip_get(
89 	struct net_bridge_mdb_htable *mdb, struct br_ip *dst, int hash)
90 {
91 	struct net_bridge_mdb_entry *mp;
92 
93 	hlist_for_each_entry_rcu(mp, &mdb->mhash[hash], hlist[mdb->ver]) {
94 		if (br_ip_equal(&mp->addr, dst))
95 			return mp;
96 	}
97 
98 	return NULL;
99 }
100 
101 struct net_bridge_mdb_entry *br_mdb_ip_get(struct net_bridge_mdb_htable *mdb,
102 					   struct br_ip *dst)
103 {
104 	if (!mdb)
105 		return NULL;
106 
107 	return __br_mdb_ip_get(mdb, dst, br_ip_hash(mdb, dst));
108 }
109 
110 static struct net_bridge_mdb_entry *br_mdb_ip4_get(
111 	struct net_bridge_mdb_htable *mdb, __be32 dst, __u16 vid)
112 {
113 	struct br_ip br_dst;
114 
115 	br_dst.u.ip4 = dst;
116 	br_dst.proto = htons(ETH_P_IP);
117 	br_dst.vid = vid;
118 
119 	return br_mdb_ip_get(mdb, &br_dst);
120 }
121 
122 #if IS_ENABLED(CONFIG_IPV6)
123 static struct net_bridge_mdb_entry *br_mdb_ip6_get(
124 	struct net_bridge_mdb_htable *mdb, const struct in6_addr *dst,
125 	__u16 vid)
126 {
127 	struct br_ip br_dst;
128 
129 	br_dst.u.ip6 = *dst;
130 	br_dst.proto = htons(ETH_P_IPV6);
131 	br_dst.vid = vid;
132 
133 	return br_mdb_ip_get(mdb, &br_dst);
134 }
135 #endif
136 
137 struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br,
138 					struct sk_buff *skb, u16 vid)
139 {
140 	struct net_bridge_mdb_htable *mdb = rcu_dereference(br->mdb);
141 	struct br_ip ip;
142 
143 	if (br->multicast_disabled)
144 		return NULL;
145 
146 	if (BR_INPUT_SKB_CB(skb)->igmp)
147 		return NULL;
148 
149 	ip.proto = skb->protocol;
150 	ip.vid = vid;
151 
152 	switch (skb->protocol) {
153 	case htons(ETH_P_IP):
154 		ip.u.ip4 = ip_hdr(skb)->daddr;
155 		break;
156 #if IS_ENABLED(CONFIG_IPV6)
157 	case htons(ETH_P_IPV6):
158 		ip.u.ip6 = ipv6_hdr(skb)->daddr;
159 		break;
160 #endif
161 	default:
162 		return NULL;
163 	}
164 
165 	return br_mdb_ip_get(mdb, &ip);
166 }
167 
168 static void br_mdb_free(struct rcu_head *head)
169 {
170 	struct net_bridge_mdb_htable *mdb =
171 		container_of(head, struct net_bridge_mdb_htable, rcu);
172 	struct net_bridge_mdb_htable *old = mdb->old;
173 
174 	mdb->old = NULL;
175 	kfree(old->mhash);
176 	kfree(old);
177 }
178 
179 static int br_mdb_copy(struct net_bridge_mdb_htable *new,
180 		       struct net_bridge_mdb_htable *old,
181 		       int elasticity)
182 {
183 	struct net_bridge_mdb_entry *mp;
184 	int maxlen;
185 	int len;
186 	int i;
187 
188 	for (i = 0; i < old->max; i++)
189 		hlist_for_each_entry(mp, &old->mhash[i], hlist[old->ver])
190 			hlist_add_head(&mp->hlist[new->ver],
191 				       &new->mhash[br_ip_hash(new, &mp->addr)]);
192 
193 	if (!elasticity)
194 		return 0;
195 
196 	maxlen = 0;
197 	for (i = 0; i < new->max; i++) {
198 		len = 0;
199 		hlist_for_each_entry(mp, &new->mhash[i], hlist[new->ver])
200 			len++;
201 		if (len > maxlen)
202 			maxlen = len;
203 	}
204 
205 	return maxlen > elasticity ? -EINVAL : 0;
206 }
207 
208 void br_multicast_free_pg(struct rcu_head *head)
209 {
210 	struct net_bridge_port_group *p =
211 		container_of(head, struct net_bridge_port_group, rcu);
212 
213 	kfree(p);
214 }
215 
216 static void br_multicast_free_group(struct rcu_head *head)
217 {
218 	struct net_bridge_mdb_entry *mp =
219 		container_of(head, struct net_bridge_mdb_entry, rcu);
220 
221 	kfree(mp);
222 }
223 
224 static void br_multicast_group_expired(unsigned long data)
225 {
226 	struct net_bridge_mdb_entry *mp = (void *)data;
227 	struct net_bridge *br = mp->br;
228 	struct net_bridge_mdb_htable *mdb;
229 
230 	spin_lock(&br->multicast_lock);
231 	if (!netif_running(br->dev) || timer_pending(&mp->timer))
232 		goto out;
233 
234 	mp->mglist = false;
235 
236 	if (mp->ports)
237 		goto out;
238 
239 	mdb = mlock_dereference(br->mdb, br);
240 
241 	hlist_del_rcu(&mp->hlist[mdb->ver]);
242 	mdb->size--;
243 
244 	call_rcu_bh(&mp->rcu, br_multicast_free_group);
245 
246 out:
247 	spin_unlock(&br->multicast_lock);
248 }
249 
250 static void br_multicast_del_pg(struct net_bridge *br,
251 				struct net_bridge_port_group *pg)
252 {
253 	struct net_bridge_mdb_htable *mdb;
254 	struct net_bridge_mdb_entry *mp;
255 	struct net_bridge_port_group *p;
256 	struct net_bridge_port_group __rcu **pp;
257 
258 	mdb = mlock_dereference(br->mdb, br);
259 
260 	mp = br_mdb_ip_get(mdb, &pg->addr);
261 	if (WARN_ON(!mp))
262 		return;
263 
264 	for (pp = &mp->ports;
265 	     (p = mlock_dereference(*pp, br)) != NULL;
266 	     pp = &p->next) {
267 		if (p != pg)
268 			continue;
269 
270 		rcu_assign_pointer(*pp, p->next);
271 		hlist_del_init(&p->mglist);
272 		del_timer(&p->timer);
273 		call_rcu_bh(&p->rcu, br_multicast_free_pg);
274 
275 		if (!mp->ports && !mp->mglist &&
276 		    netif_running(br->dev))
277 			mod_timer(&mp->timer, jiffies);
278 
279 		return;
280 	}
281 
282 	WARN_ON(1);
283 }
284 
285 static void br_multicast_port_group_expired(unsigned long data)
286 {
287 	struct net_bridge_port_group *pg = (void *)data;
288 	struct net_bridge *br = pg->port->br;
289 
290 	spin_lock(&br->multicast_lock);
291 	if (!netif_running(br->dev) || timer_pending(&pg->timer) ||
292 	    hlist_unhashed(&pg->mglist) || pg->state & MDB_PERMANENT)
293 		goto out;
294 
295 	br_multicast_del_pg(br, pg);
296 
297 out:
298 	spin_unlock(&br->multicast_lock);
299 }
300 
301 static int br_mdb_rehash(struct net_bridge_mdb_htable __rcu **mdbp, int max,
302 			 int elasticity)
303 {
304 	struct net_bridge_mdb_htable *old = rcu_dereference_protected(*mdbp, 1);
305 	struct net_bridge_mdb_htable *mdb;
306 	int err;
307 
308 	mdb = kmalloc(sizeof(*mdb), GFP_ATOMIC);
309 	if (!mdb)
310 		return -ENOMEM;
311 
312 	mdb->max = max;
313 	mdb->old = old;
314 
315 	mdb->mhash = kzalloc(max * sizeof(*mdb->mhash), GFP_ATOMIC);
316 	if (!mdb->mhash) {
317 		kfree(mdb);
318 		return -ENOMEM;
319 	}
320 
321 	mdb->size = old ? old->size : 0;
322 	mdb->ver = old ? old->ver ^ 1 : 0;
323 
324 	if (!old || elasticity)
325 		get_random_bytes(&mdb->secret, sizeof(mdb->secret));
326 	else
327 		mdb->secret = old->secret;
328 
329 	if (!old)
330 		goto out;
331 
332 	err = br_mdb_copy(mdb, old, elasticity);
333 	if (err) {
334 		kfree(mdb->mhash);
335 		kfree(mdb);
336 		return err;
337 	}
338 
339 	br_mdb_rehash_seq++;
340 	call_rcu_bh(&mdb->rcu, br_mdb_free);
341 
342 out:
343 	rcu_assign_pointer(*mdbp, mdb);
344 
345 	return 0;
346 }
347 
348 static struct sk_buff *br_ip4_multicast_alloc_query(struct net_bridge *br,
349 						    __be32 group)
350 {
351 	struct sk_buff *skb;
352 	struct igmphdr *ih;
353 	struct ethhdr *eth;
354 	struct iphdr *iph;
355 
356 	skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*iph) +
357 						 sizeof(*ih) + 4);
358 	if (!skb)
359 		goto out;
360 
361 	skb->protocol = htons(ETH_P_IP);
362 
363 	skb_reset_mac_header(skb);
364 	eth = eth_hdr(skb);
365 
366 	ether_addr_copy(eth->h_source, br->dev->dev_addr);
367 	eth->h_dest[0] = 1;
368 	eth->h_dest[1] = 0;
369 	eth->h_dest[2] = 0x5e;
370 	eth->h_dest[3] = 0;
371 	eth->h_dest[4] = 0;
372 	eth->h_dest[5] = 1;
373 	eth->h_proto = htons(ETH_P_IP);
374 	skb_put(skb, sizeof(*eth));
375 
376 	skb_set_network_header(skb, skb->len);
377 	iph = ip_hdr(skb);
378 
379 	iph->version = 4;
380 	iph->ihl = 6;
381 	iph->tos = 0xc0;
382 	iph->tot_len = htons(sizeof(*iph) + sizeof(*ih) + 4);
383 	iph->id = 0;
384 	iph->frag_off = htons(IP_DF);
385 	iph->ttl = 1;
386 	iph->protocol = IPPROTO_IGMP;
387 	iph->saddr = br->multicast_query_use_ifaddr ?
388 		     inet_select_addr(br->dev, 0, RT_SCOPE_LINK) : 0;
389 	iph->daddr = htonl(INADDR_ALLHOSTS_GROUP);
390 	((u8 *)&iph[1])[0] = IPOPT_RA;
391 	((u8 *)&iph[1])[1] = 4;
392 	((u8 *)&iph[1])[2] = 0;
393 	((u8 *)&iph[1])[3] = 0;
394 	ip_send_check(iph);
395 	skb_put(skb, 24);
396 
397 	skb_set_transport_header(skb, skb->len);
398 	ih = igmp_hdr(skb);
399 	ih->type = IGMP_HOST_MEMBERSHIP_QUERY;
400 	ih->code = (group ? br->multicast_last_member_interval :
401 			    br->multicast_query_response_interval) /
402 		   (HZ / IGMP_TIMER_SCALE);
403 	ih->group = group;
404 	ih->csum = 0;
405 	ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
406 	skb_put(skb, sizeof(*ih));
407 
408 	__skb_pull(skb, sizeof(*eth));
409 
410 out:
411 	return skb;
412 }
413 
414 #if IS_ENABLED(CONFIG_IPV6)
415 static struct sk_buff *br_ip6_multicast_alloc_query(struct net_bridge *br,
416 						    const struct in6_addr *group)
417 {
418 	struct sk_buff *skb;
419 	struct ipv6hdr *ip6h;
420 	struct mld_msg *mldq;
421 	struct ethhdr *eth;
422 	u8 *hopopt;
423 	unsigned long interval;
424 
425 	skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*ip6h) +
426 						 8 + sizeof(*mldq));
427 	if (!skb)
428 		goto out;
429 
430 	skb->protocol = htons(ETH_P_IPV6);
431 
432 	/* Ethernet header */
433 	skb_reset_mac_header(skb);
434 	eth = eth_hdr(skb);
435 
436 	ether_addr_copy(eth->h_source, br->dev->dev_addr);
437 	eth->h_proto = htons(ETH_P_IPV6);
438 	skb_put(skb, sizeof(*eth));
439 
440 	/* IPv6 header + HbH option */
441 	skb_set_network_header(skb, skb->len);
442 	ip6h = ipv6_hdr(skb);
443 
444 	*(__force __be32 *)ip6h = htonl(0x60000000);
445 	ip6h->payload_len = htons(8 + sizeof(*mldq));
446 	ip6h->nexthdr = IPPROTO_HOPOPTS;
447 	ip6h->hop_limit = 1;
448 	ipv6_addr_set(&ip6h->daddr, htonl(0xff020000), 0, 0, htonl(1));
449 	if (ipv6_dev_get_saddr(dev_net(br->dev), br->dev, &ip6h->daddr, 0,
450 			       &ip6h->saddr)) {
451 		kfree_skb(skb);
452 		return NULL;
453 	}
454 	ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest);
455 
456 	hopopt = (u8 *)(ip6h + 1);
457 	hopopt[0] = IPPROTO_ICMPV6;		/* next hdr */
458 	hopopt[1] = 0;				/* length of HbH */
459 	hopopt[2] = IPV6_TLV_ROUTERALERT;	/* Router Alert */
460 	hopopt[3] = 2;				/* Length of RA Option */
461 	hopopt[4] = 0;				/* Type = 0x0000 (MLD) */
462 	hopopt[5] = 0;
463 	hopopt[6] = IPV6_TLV_PAD1;		/* Pad1 */
464 	hopopt[7] = IPV6_TLV_PAD1;		/* Pad1 */
465 
466 	skb_put(skb, sizeof(*ip6h) + 8);
467 
468 	/* ICMPv6 */
469 	skb_set_transport_header(skb, skb->len);
470 	mldq = (struct mld_msg *) icmp6_hdr(skb);
471 
472 	interval = ipv6_addr_any(group) ?
473 			br->multicast_query_response_interval :
474 			br->multicast_last_member_interval;
475 
476 	mldq->mld_type = ICMPV6_MGM_QUERY;
477 	mldq->mld_code = 0;
478 	mldq->mld_cksum = 0;
479 	mldq->mld_maxdelay = htons((u16)jiffies_to_msecs(interval));
480 	mldq->mld_reserved = 0;
481 	mldq->mld_mca = *group;
482 
483 	/* checksum */
484 	mldq->mld_cksum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
485 					  sizeof(*mldq), IPPROTO_ICMPV6,
486 					  csum_partial(mldq,
487 						       sizeof(*mldq), 0));
488 	skb_put(skb, sizeof(*mldq));
489 
490 	__skb_pull(skb, sizeof(*eth));
491 
492 out:
493 	return skb;
494 }
495 #endif
496 
497 static struct sk_buff *br_multicast_alloc_query(struct net_bridge *br,
498 						struct br_ip *addr)
499 {
500 	switch (addr->proto) {
501 	case htons(ETH_P_IP):
502 		return br_ip4_multicast_alloc_query(br, addr->u.ip4);
503 #if IS_ENABLED(CONFIG_IPV6)
504 	case htons(ETH_P_IPV6):
505 		return br_ip6_multicast_alloc_query(br, &addr->u.ip6);
506 #endif
507 	}
508 	return NULL;
509 }
510 
511 static struct net_bridge_mdb_entry *br_multicast_get_group(
512 	struct net_bridge *br, struct net_bridge_port *port,
513 	struct br_ip *group, int hash)
514 {
515 	struct net_bridge_mdb_htable *mdb;
516 	struct net_bridge_mdb_entry *mp;
517 	unsigned int count = 0;
518 	unsigned int max;
519 	int elasticity;
520 	int err;
521 
522 	mdb = rcu_dereference_protected(br->mdb, 1);
523 	hlist_for_each_entry(mp, &mdb->mhash[hash], hlist[mdb->ver]) {
524 		count++;
525 		if (unlikely(br_ip_equal(group, &mp->addr)))
526 			return mp;
527 	}
528 
529 	elasticity = 0;
530 	max = mdb->max;
531 
532 	if (unlikely(count > br->hash_elasticity && count)) {
533 		if (net_ratelimit())
534 			br_info(br, "Multicast hash table "
535 				"chain limit reached: %s\n",
536 				port ? port->dev->name : br->dev->name);
537 
538 		elasticity = br->hash_elasticity;
539 	}
540 
541 	if (mdb->size >= max) {
542 		max *= 2;
543 		if (unlikely(max > br->hash_max)) {
544 			br_warn(br, "Multicast hash table maximum of %d "
545 				"reached, disabling snooping: %s\n",
546 				br->hash_max,
547 				port ? port->dev->name : br->dev->name);
548 			err = -E2BIG;
549 disable:
550 			br->multicast_disabled = 1;
551 			goto err;
552 		}
553 	}
554 
555 	if (max > mdb->max || elasticity) {
556 		if (mdb->old) {
557 			if (net_ratelimit())
558 				br_info(br, "Multicast hash table "
559 					"on fire: %s\n",
560 					port ? port->dev->name : br->dev->name);
561 			err = -EEXIST;
562 			goto err;
563 		}
564 
565 		err = br_mdb_rehash(&br->mdb, max, elasticity);
566 		if (err) {
567 			br_warn(br, "Cannot rehash multicast "
568 				"hash table, disabling snooping: %s, %d, %d\n",
569 				port ? port->dev->name : br->dev->name,
570 				mdb->size, err);
571 			goto disable;
572 		}
573 
574 		err = -EAGAIN;
575 		goto err;
576 	}
577 
578 	return NULL;
579 
580 err:
581 	mp = ERR_PTR(err);
582 	return mp;
583 }
584 
585 struct net_bridge_mdb_entry *br_multicast_new_group(struct net_bridge *br,
586 	struct net_bridge_port *port, struct br_ip *group)
587 {
588 	struct net_bridge_mdb_htable *mdb;
589 	struct net_bridge_mdb_entry *mp;
590 	int hash;
591 	int err;
592 
593 	mdb = rcu_dereference_protected(br->mdb, 1);
594 	if (!mdb) {
595 		err = br_mdb_rehash(&br->mdb, BR_HASH_SIZE, 0);
596 		if (err)
597 			return ERR_PTR(err);
598 		goto rehash;
599 	}
600 
601 	hash = br_ip_hash(mdb, group);
602 	mp = br_multicast_get_group(br, port, group, hash);
603 	switch (PTR_ERR(mp)) {
604 	case 0:
605 		break;
606 
607 	case -EAGAIN:
608 rehash:
609 		mdb = rcu_dereference_protected(br->mdb, 1);
610 		hash = br_ip_hash(mdb, group);
611 		break;
612 
613 	default:
614 		goto out;
615 	}
616 
617 	mp = kzalloc(sizeof(*mp), GFP_ATOMIC);
618 	if (unlikely(!mp))
619 		return ERR_PTR(-ENOMEM);
620 
621 	mp->br = br;
622 	mp->addr = *group;
623 	setup_timer(&mp->timer, br_multicast_group_expired,
624 		    (unsigned long)mp);
625 
626 	hlist_add_head_rcu(&mp->hlist[mdb->ver], &mdb->mhash[hash]);
627 	mdb->size++;
628 
629 out:
630 	return mp;
631 }
632 
633 struct net_bridge_port_group *br_multicast_new_port_group(
634 			struct net_bridge_port *port,
635 			struct br_ip *group,
636 			struct net_bridge_port_group __rcu *next,
637 			unsigned char state)
638 {
639 	struct net_bridge_port_group *p;
640 
641 	p = kzalloc(sizeof(*p), GFP_ATOMIC);
642 	if (unlikely(!p))
643 		return NULL;
644 
645 	p->addr = *group;
646 	p->port = port;
647 	p->state = state;
648 	rcu_assign_pointer(p->next, next);
649 	hlist_add_head(&p->mglist, &port->mglist);
650 	setup_timer(&p->timer, br_multicast_port_group_expired,
651 		    (unsigned long)p);
652 	return p;
653 }
654 
655 static int br_multicast_add_group(struct net_bridge *br,
656 				  struct net_bridge_port *port,
657 				  struct br_ip *group)
658 {
659 	struct net_bridge_mdb_entry *mp;
660 	struct net_bridge_port_group *p;
661 	struct net_bridge_port_group __rcu **pp;
662 	unsigned long now = jiffies;
663 	int err;
664 
665 	spin_lock(&br->multicast_lock);
666 	if (!netif_running(br->dev) ||
667 	    (port && port->state == BR_STATE_DISABLED))
668 		goto out;
669 
670 	mp = br_multicast_new_group(br, port, group);
671 	err = PTR_ERR(mp);
672 	if (IS_ERR(mp))
673 		goto err;
674 
675 	if (!port) {
676 		mp->mglist = true;
677 		mod_timer(&mp->timer, now + br->multicast_membership_interval);
678 		goto out;
679 	}
680 
681 	for (pp = &mp->ports;
682 	     (p = mlock_dereference(*pp, br)) != NULL;
683 	     pp = &p->next) {
684 		if (p->port == port)
685 			goto found;
686 		if ((unsigned long)p->port < (unsigned long)port)
687 			break;
688 	}
689 
690 	p = br_multicast_new_port_group(port, group, *pp, MDB_TEMPORARY);
691 	if (unlikely(!p))
692 		goto err;
693 	rcu_assign_pointer(*pp, p);
694 	br_mdb_notify(br->dev, port, group, RTM_NEWMDB);
695 
696 found:
697 	mod_timer(&p->timer, now + br->multicast_membership_interval);
698 out:
699 	err = 0;
700 
701 err:
702 	spin_unlock(&br->multicast_lock);
703 	return err;
704 }
705 
706 static int br_ip4_multicast_add_group(struct net_bridge *br,
707 				      struct net_bridge_port *port,
708 				      __be32 group,
709 				      __u16 vid)
710 {
711 	struct br_ip br_group;
712 
713 	if (ipv4_is_local_multicast(group))
714 		return 0;
715 
716 	br_group.u.ip4 = group;
717 	br_group.proto = htons(ETH_P_IP);
718 	br_group.vid = vid;
719 
720 	return br_multicast_add_group(br, port, &br_group);
721 }
722 
723 #if IS_ENABLED(CONFIG_IPV6)
724 static int br_ip6_multicast_add_group(struct net_bridge *br,
725 				      struct net_bridge_port *port,
726 				      const struct in6_addr *group,
727 				      __u16 vid)
728 {
729 	struct br_ip br_group;
730 
731 	if (ipv6_addr_is_ll_all_nodes(group))
732 		return 0;
733 
734 	br_group.u.ip6 = *group;
735 	br_group.proto = htons(ETH_P_IPV6);
736 	br_group.vid = vid;
737 
738 	return br_multicast_add_group(br, port, &br_group);
739 }
740 #endif
741 
742 static void br_multicast_router_expired(unsigned long data)
743 {
744 	struct net_bridge_port *port = (void *)data;
745 	struct net_bridge *br = port->br;
746 
747 	spin_lock(&br->multicast_lock);
748 	if (port->multicast_router != 1 ||
749 	    timer_pending(&port->multicast_router_timer) ||
750 	    hlist_unhashed(&port->rlist))
751 		goto out;
752 
753 	hlist_del_init_rcu(&port->rlist);
754 
755 out:
756 	spin_unlock(&br->multicast_lock);
757 }
758 
759 static void br_multicast_local_router_expired(unsigned long data)
760 {
761 }
762 
763 static void br_multicast_querier_expired(struct net_bridge *br,
764 					 struct bridge_mcast_query *query)
765 {
766 	spin_lock(&br->multicast_lock);
767 	if (!netif_running(br->dev) || br->multicast_disabled)
768 		goto out;
769 
770 	br_multicast_start_querier(br, query);
771 
772 out:
773 	spin_unlock(&br->multicast_lock);
774 }
775 
776 static void br_ip4_multicast_querier_expired(unsigned long data)
777 {
778 	struct net_bridge *br = (void *)data;
779 
780 	br_multicast_querier_expired(br, &br->ip4_query);
781 }
782 
783 #if IS_ENABLED(CONFIG_IPV6)
784 static void br_ip6_multicast_querier_expired(unsigned long data)
785 {
786 	struct net_bridge *br = (void *)data;
787 
788 	br_multicast_querier_expired(br, &br->ip6_query);
789 }
790 #endif
791 
792 static void __br_multicast_send_query(struct net_bridge *br,
793 				      struct net_bridge_port *port,
794 				      struct br_ip *ip)
795 {
796 	struct sk_buff *skb;
797 
798 	skb = br_multicast_alloc_query(br, ip);
799 	if (!skb)
800 		return;
801 
802 	if (port) {
803 		__skb_push(skb, sizeof(struct ethhdr));
804 		skb->dev = port->dev;
805 		NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
806 			dev_queue_xmit);
807 	} else
808 		netif_rx(skb);
809 }
810 
811 static void br_multicast_send_query(struct net_bridge *br,
812 				    struct net_bridge_port *port,
813 				    struct bridge_mcast_query *query)
814 {
815 	unsigned long time;
816 	struct br_ip br_group;
817 	struct bridge_mcast_querier *querier = NULL;
818 
819 	if (!netif_running(br->dev) || br->multicast_disabled ||
820 	    !br->multicast_querier)
821 		return;
822 
823 	memset(&br_group.u, 0, sizeof(br_group.u));
824 
825 	if (port ? (query == &port->ip4_query) :
826 		   (query == &br->ip4_query)) {
827 		querier = &br->ip4_querier;
828 		br_group.proto = htons(ETH_P_IP);
829 #if IS_ENABLED(CONFIG_IPV6)
830 	} else {
831 		querier = &br->ip6_querier;
832 		br_group.proto = htons(ETH_P_IPV6);
833 #endif
834 	}
835 
836 	if (!querier || timer_pending(&querier->timer))
837 		return;
838 
839 	__br_multicast_send_query(br, port, &br_group);
840 
841 	time = jiffies;
842 	time += query->startup_sent < br->multicast_startup_query_count ?
843 		br->multicast_startup_query_interval :
844 		br->multicast_query_interval;
845 	mod_timer(&query->timer, time);
846 }
847 
848 static void br_multicast_port_query_expired(struct net_bridge_port *port,
849 					    struct bridge_mcast_query *query)
850 {
851 	struct net_bridge *br = port->br;
852 
853 	spin_lock(&br->multicast_lock);
854 	if (port->state == BR_STATE_DISABLED ||
855 	    port->state == BR_STATE_BLOCKING)
856 		goto out;
857 
858 	if (query->startup_sent < br->multicast_startup_query_count)
859 		query->startup_sent++;
860 
861 	br_multicast_send_query(port->br, port, query);
862 
863 out:
864 	spin_unlock(&br->multicast_lock);
865 }
866 
867 static void br_ip4_multicast_port_query_expired(unsigned long data)
868 {
869 	struct net_bridge_port *port = (void *)data;
870 
871 	br_multicast_port_query_expired(port, &port->ip4_query);
872 }
873 
874 #if IS_ENABLED(CONFIG_IPV6)
875 static void br_ip6_multicast_port_query_expired(unsigned long data)
876 {
877 	struct net_bridge_port *port = (void *)data;
878 
879 	br_multicast_port_query_expired(port, &port->ip6_query);
880 }
881 #endif
882 
883 void br_multicast_add_port(struct net_bridge_port *port)
884 {
885 	port->multicast_router = 1;
886 
887 	setup_timer(&port->multicast_router_timer, br_multicast_router_expired,
888 		    (unsigned long)port);
889 	setup_timer(&port->ip4_query.timer, br_ip4_multicast_port_query_expired,
890 		    (unsigned long)port);
891 #if IS_ENABLED(CONFIG_IPV6)
892 	setup_timer(&port->ip6_query.timer, br_ip6_multicast_port_query_expired,
893 		    (unsigned long)port);
894 #endif
895 }
896 
897 void br_multicast_del_port(struct net_bridge_port *port)
898 {
899 	del_timer_sync(&port->multicast_router_timer);
900 }
901 
902 static void br_multicast_enable(struct bridge_mcast_query *query)
903 {
904 	query->startup_sent = 0;
905 
906 	if (try_to_del_timer_sync(&query->timer) >= 0 ||
907 	    del_timer(&query->timer))
908 		mod_timer(&query->timer, jiffies);
909 }
910 
911 void br_multicast_enable_port(struct net_bridge_port *port)
912 {
913 	struct net_bridge *br = port->br;
914 
915 	spin_lock(&br->multicast_lock);
916 	if (br->multicast_disabled || !netif_running(br->dev))
917 		goto out;
918 
919 	br_multicast_enable(&port->ip4_query);
920 #if IS_ENABLED(CONFIG_IPV6)
921 	br_multicast_enable(&port->ip6_query);
922 #endif
923 
924 out:
925 	spin_unlock(&br->multicast_lock);
926 }
927 
928 void br_multicast_disable_port(struct net_bridge_port *port)
929 {
930 	struct net_bridge *br = port->br;
931 	struct net_bridge_port_group *pg;
932 	struct hlist_node *n;
933 
934 	spin_lock(&br->multicast_lock);
935 	hlist_for_each_entry_safe(pg, n, &port->mglist, mglist)
936 		br_multicast_del_pg(br, pg);
937 
938 	if (!hlist_unhashed(&port->rlist))
939 		hlist_del_init_rcu(&port->rlist);
940 	del_timer(&port->multicast_router_timer);
941 	del_timer(&port->ip4_query.timer);
942 #if IS_ENABLED(CONFIG_IPV6)
943 	del_timer(&port->ip6_query.timer);
944 #endif
945 	spin_unlock(&br->multicast_lock);
946 }
947 
948 static int br_ip4_multicast_igmp3_report(struct net_bridge *br,
949 					 struct net_bridge_port *port,
950 					 struct sk_buff *skb,
951 					 u16 vid)
952 {
953 	struct igmpv3_report *ih;
954 	struct igmpv3_grec *grec;
955 	int i;
956 	int len;
957 	int num;
958 	int type;
959 	int err = 0;
960 	__be32 group;
961 
962 	if (!pskb_may_pull(skb, sizeof(*ih)))
963 		return -EINVAL;
964 
965 	ih = igmpv3_report_hdr(skb);
966 	num = ntohs(ih->ngrec);
967 	len = sizeof(*ih);
968 
969 	for (i = 0; i < num; i++) {
970 		len += sizeof(*grec);
971 		if (!pskb_may_pull(skb, len))
972 			return -EINVAL;
973 
974 		grec = (void *)(skb->data + len - sizeof(*grec));
975 		group = grec->grec_mca;
976 		type = grec->grec_type;
977 
978 		len += ntohs(grec->grec_nsrcs) * 4;
979 		if (!pskb_may_pull(skb, len))
980 			return -EINVAL;
981 
982 		/* We treat this as an IGMPv2 report for now. */
983 		switch (type) {
984 		case IGMPV3_MODE_IS_INCLUDE:
985 		case IGMPV3_MODE_IS_EXCLUDE:
986 		case IGMPV3_CHANGE_TO_INCLUDE:
987 		case IGMPV3_CHANGE_TO_EXCLUDE:
988 		case IGMPV3_ALLOW_NEW_SOURCES:
989 		case IGMPV3_BLOCK_OLD_SOURCES:
990 			break;
991 
992 		default:
993 			continue;
994 		}
995 
996 		err = br_ip4_multicast_add_group(br, port, group, vid);
997 		if (err)
998 			break;
999 	}
1000 
1001 	return err;
1002 }
1003 
1004 #if IS_ENABLED(CONFIG_IPV6)
1005 static int br_ip6_multicast_mld2_report(struct net_bridge *br,
1006 					struct net_bridge_port *port,
1007 					struct sk_buff *skb,
1008 					u16 vid)
1009 {
1010 	struct icmp6hdr *icmp6h;
1011 	struct mld2_grec *grec;
1012 	int i;
1013 	int len;
1014 	int num;
1015 	int err = 0;
1016 
1017 	if (!pskb_may_pull(skb, sizeof(*icmp6h)))
1018 		return -EINVAL;
1019 
1020 	icmp6h = icmp6_hdr(skb);
1021 	num = ntohs(icmp6h->icmp6_dataun.un_data16[1]);
1022 	len = sizeof(*icmp6h);
1023 
1024 	for (i = 0; i < num; i++) {
1025 		__be16 *nsrcs, _nsrcs;
1026 
1027 		nsrcs = skb_header_pointer(skb,
1028 					   len + offsetof(struct mld2_grec,
1029 							  grec_nsrcs),
1030 					   sizeof(_nsrcs), &_nsrcs);
1031 		if (!nsrcs)
1032 			return -EINVAL;
1033 
1034 		if (!pskb_may_pull(skb,
1035 				   len + sizeof(*grec) +
1036 				   sizeof(struct in6_addr) * ntohs(*nsrcs)))
1037 			return -EINVAL;
1038 
1039 		grec = (struct mld2_grec *)(skb->data + len);
1040 		len += sizeof(*grec) +
1041 		       sizeof(struct in6_addr) * ntohs(*nsrcs);
1042 
1043 		/* We treat these as MLDv1 reports for now. */
1044 		switch (grec->grec_type) {
1045 		case MLD2_MODE_IS_INCLUDE:
1046 		case MLD2_MODE_IS_EXCLUDE:
1047 		case MLD2_CHANGE_TO_INCLUDE:
1048 		case MLD2_CHANGE_TO_EXCLUDE:
1049 		case MLD2_ALLOW_NEW_SOURCES:
1050 		case MLD2_BLOCK_OLD_SOURCES:
1051 			break;
1052 
1053 		default:
1054 			continue;
1055 		}
1056 
1057 		err = br_ip6_multicast_add_group(br, port, &grec->grec_mca,
1058 						 vid);
1059 		if (!err)
1060 			break;
1061 	}
1062 
1063 	return err;
1064 }
1065 #endif
1066 
1067 static void
1068 br_multicast_update_querier_timer(struct net_bridge *br,
1069 				  struct bridge_mcast_querier *querier,
1070 				  unsigned long max_delay)
1071 {
1072 	if (!timer_pending(&querier->timer))
1073 		querier->delay_time = jiffies + max_delay;
1074 
1075 	mod_timer(&querier->timer, jiffies + br->multicast_querier_interval);
1076 }
1077 
1078 /*
1079  * Add port to router_list
1080  *  list is maintained ordered by pointer value
1081  *  and locked by br->multicast_lock and RCU
1082  */
1083 static void br_multicast_add_router(struct net_bridge *br,
1084 				    struct net_bridge_port *port)
1085 {
1086 	struct net_bridge_port *p;
1087 	struct hlist_node *slot = NULL;
1088 
1089 	hlist_for_each_entry(p, &br->router_list, rlist) {
1090 		if ((unsigned long) port >= (unsigned long) p)
1091 			break;
1092 		slot = &p->rlist;
1093 	}
1094 
1095 	if (slot)
1096 		hlist_add_after_rcu(slot, &port->rlist);
1097 	else
1098 		hlist_add_head_rcu(&port->rlist, &br->router_list);
1099 }
1100 
1101 static void br_multicast_mark_router(struct net_bridge *br,
1102 				     struct net_bridge_port *port)
1103 {
1104 	unsigned long now = jiffies;
1105 
1106 	if (!port) {
1107 		if (br->multicast_router == 1)
1108 			mod_timer(&br->multicast_router_timer,
1109 				  now + br->multicast_querier_interval);
1110 		return;
1111 	}
1112 
1113 	if (port->multicast_router != 1)
1114 		return;
1115 
1116 	if (!hlist_unhashed(&port->rlist))
1117 		goto timer;
1118 
1119 	br_multicast_add_router(br, port);
1120 
1121 timer:
1122 	mod_timer(&port->multicast_router_timer,
1123 		  now + br->multicast_querier_interval);
1124 }
1125 
1126 static void br_multicast_query_received(struct net_bridge *br,
1127 					struct net_bridge_port *port,
1128 					struct bridge_mcast_querier *querier,
1129 					int saddr,
1130 					bool is_general_query,
1131 					unsigned long max_delay)
1132 {
1133 	if (saddr && is_general_query)
1134 		br_multicast_update_querier_timer(br, querier, max_delay);
1135 	else if (timer_pending(&querier->timer))
1136 		return;
1137 
1138 	br_multicast_mark_router(br, port);
1139 }
1140 
1141 static int br_ip4_multicast_query(struct net_bridge *br,
1142 				  struct net_bridge_port *port,
1143 				  struct sk_buff *skb,
1144 				  u16 vid)
1145 {
1146 	const struct iphdr *iph = ip_hdr(skb);
1147 	struct igmphdr *ih = igmp_hdr(skb);
1148 	struct net_bridge_mdb_entry *mp;
1149 	struct igmpv3_query *ih3;
1150 	struct net_bridge_port_group *p;
1151 	struct net_bridge_port_group __rcu **pp;
1152 	unsigned long max_delay;
1153 	unsigned long now = jiffies;
1154 	__be32 group;
1155 	int err = 0;
1156 
1157 	spin_lock(&br->multicast_lock);
1158 	if (!netif_running(br->dev) ||
1159 	    (port && port->state == BR_STATE_DISABLED))
1160 		goto out;
1161 
1162 	group = ih->group;
1163 
1164 	if (skb->len == sizeof(*ih)) {
1165 		max_delay = ih->code * (HZ / IGMP_TIMER_SCALE);
1166 
1167 		if (!max_delay) {
1168 			max_delay = 10 * HZ;
1169 			group = 0;
1170 		}
1171 	} else {
1172 		if (!pskb_may_pull(skb, sizeof(struct igmpv3_query))) {
1173 			err = -EINVAL;
1174 			goto out;
1175 		}
1176 
1177 		ih3 = igmpv3_query_hdr(skb);
1178 		if (ih3->nsrcs)
1179 			goto out;
1180 
1181 		max_delay = ih3->code ?
1182 			    IGMPV3_MRC(ih3->code) * (HZ / IGMP_TIMER_SCALE) : 1;
1183 	}
1184 
1185 	/* RFC2236+RFC3376 (IGMPv2+IGMPv3) require the multicast link layer
1186 	 * all-systems destination addresses (224.0.0.1) for general queries
1187 	 */
1188 	if (!group && iph->daddr != htonl(INADDR_ALLHOSTS_GROUP)) {
1189 		err = -EINVAL;
1190 		goto out;
1191 	}
1192 
1193 	br_multicast_query_received(br, port, &br->ip4_querier, !!iph->saddr,
1194 				    !group, max_delay);
1195 
1196 	if (!group)
1197 		goto out;
1198 
1199 	mp = br_mdb_ip4_get(mlock_dereference(br->mdb, br), group, vid);
1200 	if (!mp)
1201 		goto out;
1202 
1203 	max_delay *= br->multicast_last_member_count;
1204 
1205 	if (mp->mglist &&
1206 	    (timer_pending(&mp->timer) ?
1207 	     time_after(mp->timer.expires, now + max_delay) :
1208 	     try_to_del_timer_sync(&mp->timer) >= 0))
1209 		mod_timer(&mp->timer, now + max_delay);
1210 
1211 	for (pp = &mp->ports;
1212 	     (p = mlock_dereference(*pp, br)) != NULL;
1213 	     pp = &p->next) {
1214 		if (timer_pending(&p->timer) ?
1215 		    time_after(p->timer.expires, now + max_delay) :
1216 		    try_to_del_timer_sync(&p->timer) >= 0)
1217 			mod_timer(&p->timer, now + max_delay);
1218 	}
1219 
1220 out:
1221 	spin_unlock(&br->multicast_lock);
1222 	return err;
1223 }
1224 
1225 #if IS_ENABLED(CONFIG_IPV6)
1226 static int br_ip6_multicast_query(struct net_bridge *br,
1227 				  struct net_bridge_port *port,
1228 				  struct sk_buff *skb,
1229 				  u16 vid)
1230 {
1231 	const struct ipv6hdr *ip6h = ipv6_hdr(skb);
1232 	struct mld_msg *mld;
1233 	struct net_bridge_mdb_entry *mp;
1234 	struct mld2_query *mld2q;
1235 	struct net_bridge_port_group *p;
1236 	struct net_bridge_port_group __rcu **pp;
1237 	unsigned long max_delay;
1238 	unsigned long now = jiffies;
1239 	const struct in6_addr *group = NULL;
1240 	bool is_general_query;
1241 	int err = 0;
1242 
1243 	spin_lock(&br->multicast_lock);
1244 	if (!netif_running(br->dev) ||
1245 	    (port && port->state == BR_STATE_DISABLED))
1246 		goto out;
1247 
1248 	/* RFC2710+RFC3810 (MLDv1+MLDv2) require link-local source addresses */
1249 	if (!(ipv6_addr_type(&ip6h->saddr) & IPV6_ADDR_LINKLOCAL)) {
1250 		err = -EINVAL;
1251 		goto out;
1252 	}
1253 
1254 	if (skb->len == sizeof(*mld)) {
1255 		if (!pskb_may_pull(skb, sizeof(*mld))) {
1256 			err = -EINVAL;
1257 			goto out;
1258 		}
1259 		mld = (struct mld_msg *) icmp6_hdr(skb);
1260 		max_delay = msecs_to_jiffies(ntohs(mld->mld_maxdelay));
1261 		if (max_delay)
1262 			group = &mld->mld_mca;
1263 	} else {
1264 		if (!pskb_may_pull(skb, sizeof(*mld2q))) {
1265 			err = -EINVAL;
1266 			goto out;
1267 		}
1268 		mld2q = (struct mld2_query *)icmp6_hdr(skb);
1269 		if (!mld2q->mld2q_nsrcs)
1270 			group = &mld2q->mld2q_mca;
1271 
1272 		max_delay = max(msecs_to_jiffies(mldv2_mrc(mld2q)), 1UL);
1273 	}
1274 
1275 	is_general_query = group && ipv6_addr_any(group);
1276 
1277 	/* RFC2710+RFC3810 (MLDv1+MLDv2) require the multicast link layer
1278 	 * all-nodes destination address (ff02::1) for general queries
1279 	 */
1280 	if (is_general_query && !ipv6_addr_is_ll_all_nodes(&ip6h->daddr)) {
1281 		err = -EINVAL;
1282 		goto out;
1283 	}
1284 
1285 	br_multicast_query_received(br, port, &br->ip6_querier,
1286 				    !ipv6_addr_any(&ip6h->saddr),
1287 				    is_general_query, max_delay);
1288 
1289 	if (!group)
1290 		goto out;
1291 
1292 	mp = br_mdb_ip6_get(mlock_dereference(br->mdb, br), group, vid);
1293 	if (!mp)
1294 		goto out;
1295 
1296 	max_delay *= br->multicast_last_member_count;
1297 	if (mp->mglist &&
1298 	    (timer_pending(&mp->timer) ?
1299 	     time_after(mp->timer.expires, now + max_delay) :
1300 	     try_to_del_timer_sync(&mp->timer) >= 0))
1301 		mod_timer(&mp->timer, now + max_delay);
1302 
1303 	for (pp = &mp->ports;
1304 	     (p = mlock_dereference(*pp, br)) != NULL;
1305 	     pp = &p->next) {
1306 		if (timer_pending(&p->timer) ?
1307 		    time_after(p->timer.expires, now + max_delay) :
1308 		    try_to_del_timer_sync(&p->timer) >= 0)
1309 			mod_timer(&p->timer, now + max_delay);
1310 	}
1311 
1312 out:
1313 	spin_unlock(&br->multicast_lock);
1314 	return err;
1315 }
1316 #endif
1317 
1318 static void br_multicast_leave_group(struct net_bridge *br,
1319 				     struct net_bridge_port *port,
1320 				     struct br_ip *group,
1321 				     struct bridge_mcast_querier *querier,
1322 				     struct bridge_mcast_query *query)
1323 {
1324 	struct net_bridge_mdb_htable *mdb;
1325 	struct net_bridge_mdb_entry *mp;
1326 	struct net_bridge_port_group *p;
1327 	unsigned long now;
1328 	unsigned long time;
1329 
1330 	spin_lock(&br->multicast_lock);
1331 	if (!netif_running(br->dev) ||
1332 	    (port && port->state == BR_STATE_DISABLED) ||
1333 	    timer_pending(&querier->timer))
1334 		goto out;
1335 
1336 	mdb = mlock_dereference(br->mdb, br);
1337 	mp = br_mdb_ip_get(mdb, group);
1338 	if (!mp)
1339 		goto out;
1340 
1341 	if (br->multicast_querier) {
1342 		__br_multicast_send_query(br, port, &mp->addr);
1343 
1344 		time = jiffies + br->multicast_last_member_count *
1345 				 br->multicast_last_member_interval;
1346 
1347 		mod_timer(&query->timer, time);
1348 
1349 		for (p = mlock_dereference(mp->ports, br);
1350 		     p != NULL;
1351 		     p = mlock_dereference(p->next, br)) {
1352 			if (p->port != port)
1353 				continue;
1354 
1355 			if (!hlist_unhashed(&p->mglist) &&
1356 			    (timer_pending(&p->timer) ?
1357 			     time_after(p->timer.expires, time) :
1358 			     try_to_del_timer_sync(&p->timer) >= 0)) {
1359 				mod_timer(&p->timer, time);
1360 			}
1361 
1362 			break;
1363 		}
1364 	}
1365 
1366 	if (port && (port->flags & BR_MULTICAST_FAST_LEAVE)) {
1367 		struct net_bridge_port_group __rcu **pp;
1368 
1369 		for (pp = &mp->ports;
1370 		     (p = mlock_dereference(*pp, br)) != NULL;
1371 		     pp = &p->next) {
1372 			if (p->port != port)
1373 				continue;
1374 
1375 			rcu_assign_pointer(*pp, p->next);
1376 			hlist_del_init(&p->mglist);
1377 			del_timer(&p->timer);
1378 			call_rcu_bh(&p->rcu, br_multicast_free_pg);
1379 			br_mdb_notify(br->dev, port, group, RTM_DELMDB);
1380 
1381 			if (!mp->ports && !mp->mglist &&
1382 			    netif_running(br->dev))
1383 				mod_timer(&mp->timer, jiffies);
1384 		}
1385 		goto out;
1386 	}
1387 
1388 	now = jiffies;
1389 	time = now + br->multicast_last_member_count *
1390 		     br->multicast_last_member_interval;
1391 
1392 	if (!port) {
1393 		if (mp->mglist &&
1394 		    (timer_pending(&mp->timer) ?
1395 		     time_after(mp->timer.expires, time) :
1396 		     try_to_del_timer_sync(&mp->timer) >= 0)) {
1397 			mod_timer(&mp->timer, time);
1398 		}
1399 
1400 		goto out;
1401 	}
1402 
1403 	for (p = mlock_dereference(mp->ports, br);
1404 	     p != NULL;
1405 	     p = mlock_dereference(p->next, br)) {
1406 		if (p->port != port)
1407 			continue;
1408 
1409 		if (!hlist_unhashed(&p->mglist) &&
1410 		    (timer_pending(&p->timer) ?
1411 		     time_after(p->timer.expires, time) :
1412 		     try_to_del_timer_sync(&p->timer) >= 0)) {
1413 			mod_timer(&p->timer, time);
1414 		}
1415 
1416 		break;
1417 	}
1418 out:
1419 	spin_unlock(&br->multicast_lock);
1420 }
1421 
1422 static void br_ip4_multicast_leave_group(struct net_bridge *br,
1423 					 struct net_bridge_port *port,
1424 					 __be32 group,
1425 					 __u16 vid)
1426 {
1427 	struct br_ip br_group;
1428 	struct bridge_mcast_query *query = port ? &port->ip4_query :
1429 						  &br->ip4_query;
1430 
1431 	if (ipv4_is_local_multicast(group))
1432 		return;
1433 
1434 	br_group.u.ip4 = group;
1435 	br_group.proto = htons(ETH_P_IP);
1436 	br_group.vid = vid;
1437 
1438 	br_multicast_leave_group(br, port, &br_group, &br->ip4_querier, query);
1439 }
1440 
1441 #if IS_ENABLED(CONFIG_IPV6)
1442 static void br_ip6_multicast_leave_group(struct net_bridge *br,
1443 					 struct net_bridge_port *port,
1444 					 const struct in6_addr *group,
1445 					 __u16 vid)
1446 {
1447 	struct br_ip br_group;
1448 	struct bridge_mcast_query *query = port ? &port->ip6_query :
1449 						  &br->ip6_query;
1450 
1451 
1452 	if (ipv6_addr_is_ll_all_nodes(group))
1453 		return;
1454 
1455 	br_group.u.ip6 = *group;
1456 	br_group.proto = htons(ETH_P_IPV6);
1457 	br_group.vid = vid;
1458 
1459 	br_multicast_leave_group(br, port, &br_group, &br->ip6_querier, query);
1460 }
1461 #endif
1462 
1463 static int br_multicast_ipv4_rcv(struct net_bridge *br,
1464 				 struct net_bridge_port *port,
1465 				 struct sk_buff *skb,
1466 				 u16 vid)
1467 {
1468 	struct sk_buff *skb2 = skb;
1469 	const struct iphdr *iph;
1470 	struct igmphdr *ih;
1471 	unsigned int len;
1472 	unsigned int offset;
1473 	int err;
1474 
1475 	/* We treat OOM as packet loss for now. */
1476 	if (!pskb_may_pull(skb, sizeof(*iph)))
1477 		return -EINVAL;
1478 
1479 	iph = ip_hdr(skb);
1480 
1481 	if (iph->ihl < 5 || iph->version != 4)
1482 		return -EINVAL;
1483 
1484 	if (!pskb_may_pull(skb, ip_hdrlen(skb)))
1485 		return -EINVAL;
1486 
1487 	iph = ip_hdr(skb);
1488 
1489 	if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1490 		return -EINVAL;
1491 
1492 	if (iph->protocol != IPPROTO_IGMP) {
1493 		if (!ipv4_is_local_multicast(iph->daddr))
1494 			BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1495 		return 0;
1496 	}
1497 
1498 	len = ntohs(iph->tot_len);
1499 	if (skb->len < len || len < ip_hdrlen(skb))
1500 		return -EINVAL;
1501 
1502 	if (skb->len > len) {
1503 		skb2 = skb_clone(skb, GFP_ATOMIC);
1504 		if (!skb2)
1505 			return -ENOMEM;
1506 
1507 		err = pskb_trim_rcsum(skb2, len);
1508 		if (err)
1509 			goto err_out;
1510 	}
1511 
1512 	len -= ip_hdrlen(skb2);
1513 	offset = skb_network_offset(skb2) + ip_hdrlen(skb2);
1514 	__skb_pull(skb2, offset);
1515 	skb_reset_transport_header(skb2);
1516 
1517 	err = -EINVAL;
1518 	if (!pskb_may_pull(skb2, sizeof(*ih)))
1519 		goto out;
1520 
1521 	switch (skb2->ip_summed) {
1522 	case CHECKSUM_COMPLETE:
1523 		if (!csum_fold(skb2->csum))
1524 			break;
1525 		/* fall through */
1526 	case CHECKSUM_NONE:
1527 		skb2->csum = 0;
1528 		if (skb_checksum_complete(skb2))
1529 			goto out;
1530 	}
1531 
1532 	err = 0;
1533 
1534 	BR_INPUT_SKB_CB(skb)->igmp = 1;
1535 	ih = igmp_hdr(skb2);
1536 
1537 	switch (ih->type) {
1538 	case IGMP_HOST_MEMBERSHIP_REPORT:
1539 	case IGMPV2_HOST_MEMBERSHIP_REPORT:
1540 		BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1541 		err = br_ip4_multicast_add_group(br, port, ih->group, vid);
1542 		break;
1543 	case IGMPV3_HOST_MEMBERSHIP_REPORT:
1544 		err = br_ip4_multicast_igmp3_report(br, port, skb2, vid);
1545 		break;
1546 	case IGMP_HOST_MEMBERSHIP_QUERY:
1547 		err = br_ip4_multicast_query(br, port, skb2, vid);
1548 		break;
1549 	case IGMP_HOST_LEAVE_MESSAGE:
1550 		br_ip4_multicast_leave_group(br, port, ih->group, vid);
1551 		break;
1552 	}
1553 
1554 out:
1555 	__skb_push(skb2, offset);
1556 err_out:
1557 	if (skb2 != skb)
1558 		kfree_skb(skb2);
1559 	return err;
1560 }
1561 
1562 #if IS_ENABLED(CONFIG_IPV6)
1563 static int br_multicast_ipv6_rcv(struct net_bridge *br,
1564 				 struct net_bridge_port *port,
1565 				 struct sk_buff *skb,
1566 				 u16 vid)
1567 {
1568 	struct sk_buff *skb2;
1569 	const struct ipv6hdr *ip6h;
1570 	u8 icmp6_type;
1571 	u8 nexthdr;
1572 	__be16 frag_off;
1573 	unsigned int len;
1574 	int offset;
1575 	int err;
1576 
1577 	if (!pskb_may_pull(skb, sizeof(*ip6h)))
1578 		return -EINVAL;
1579 
1580 	ip6h = ipv6_hdr(skb);
1581 
1582 	/*
1583 	 * We're interested in MLD messages only.
1584 	 *  - Version is 6
1585 	 *  - MLD has always Router Alert hop-by-hop option
1586 	 *  - But we do not support jumbrograms.
1587 	 */
1588 	if (ip6h->version != 6)
1589 		return 0;
1590 
1591 	/* Prevent flooding this packet if there is no listener present */
1592 	if (!ipv6_addr_is_ll_all_nodes(&ip6h->daddr))
1593 		BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1594 
1595 	if (ip6h->nexthdr != IPPROTO_HOPOPTS ||
1596 	    ip6h->payload_len == 0)
1597 		return 0;
1598 
1599 	len = ntohs(ip6h->payload_len) + sizeof(*ip6h);
1600 	if (skb->len < len)
1601 		return -EINVAL;
1602 
1603 	nexthdr = ip6h->nexthdr;
1604 	offset = ipv6_skip_exthdr(skb, sizeof(*ip6h), &nexthdr, &frag_off);
1605 
1606 	if (offset < 0 || nexthdr != IPPROTO_ICMPV6)
1607 		return 0;
1608 
1609 	/* Okay, we found ICMPv6 header */
1610 	skb2 = skb_clone(skb, GFP_ATOMIC);
1611 	if (!skb2)
1612 		return -ENOMEM;
1613 
1614 	err = -EINVAL;
1615 	if (!pskb_may_pull(skb2, offset + sizeof(struct icmp6hdr)))
1616 		goto out;
1617 
1618 	len -= offset - skb_network_offset(skb2);
1619 
1620 	__skb_pull(skb2, offset);
1621 	skb_reset_transport_header(skb2);
1622 	skb_postpull_rcsum(skb2, skb_network_header(skb2),
1623 			   skb_network_header_len(skb2));
1624 
1625 	icmp6_type = icmp6_hdr(skb2)->icmp6_type;
1626 
1627 	switch (icmp6_type) {
1628 	case ICMPV6_MGM_QUERY:
1629 	case ICMPV6_MGM_REPORT:
1630 	case ICMPV6_MGM_REDUCTION:
1631 	case ICMPV6_MLD2_REPORT:
1632 		break;
1633 	default:
1634 		err = 0;
1635 		goto out;
1636 	}
1637 
1638 	/* Okay, we found MLD message. Check further. */
1639 	if (skb2->len > len) {
1640 		err = pskb_trim_rcsum(skb2, len);
1641 		if (err)
1642 			goto out;
1643 		err = -EINVAL;
1644 	}
1645 
1646 	ip6h = ipv6_hdr(skb2);
1647 
1648 	switch (skb2->ip_summed) {
1649 	case CHECKSUM_COMPLETE:
1650 		if (!csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, skb2->len,
1651 					IPPROTO_ICMPV6, skb2->csum))
1652 			break;
1653 		/*FALLTHROUGH*/
1654 	case CHECKSUM_NONE:
1655 		skb2->csum = ~csum_unfold(csum_ipv6_magic(&ip6h->saddr,
1656 							&ip6h->daddr,
1657 							skb2->len,
1658 							IPPROTO_ICMPV6, 0));
1659 		if (__skb_checksum_complete(skb2))
1660 			goto out;
1661 	}
1662 
1663 	err = 0;
1664 
1665 	BR_INPUT_SKB_CB(skb)->igmp = 1;
1666 
1667 	switch (icmp6_type) {
1668 	case ICMPV6_MGM_REPORT:
1669 	    {
1670 		struct mld_msg *mld;
1671 		if (!pskb_may_pull(skb2, sizeof(*mld))) {
1672 			err = -EINVAL;
1673 			goto out;
1674 		}
1675 		mld = (struct mld_msg *)skb_transport_header(skb2);
1676 		BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1677 		err = br_ip6_multicast_add_group(br, port, &mld->mld_mca, vid);
1678 		break;
1679 	    }
1680 	case ICMPV6_MLD2_REPORT:
1681 		err = br_ip6_multicast_mld2_report(br, port, skb2, vid);
1682 		break;
1683 	case ICMPV6_MGM_QUERY:
1684 		err = br_ip6_multicast_query(br, port, skb2, vid);
1685 		break;
1686 	case ICMPV6_MGM_REDUCTION:
1687 	    {
1688 		struct mld_msg *mld;
1689 		if (!pskb_may_pull(skb2, sizeof(*mld))) {
1690 			err = -EINVAL;
1691 			goto out;
1692 		}
1693 		mld = (struct mld_msg *)skb_transport_header(skb2);
1694 		br_ip6_multicast_leave_group(br, port, &mld->mld_mca, vid);
1695 	    }
1696 	}
1697 
1698 out:
1699 	kfree_skb(skb2);
1700 	return err;
1701 }
1702 #endif
1703 
1704 int br_multicast_rcv(struct net_bridge *br, struct net_bridge_port *port,
1705 		     struct sk_buff *skb, u16 vid)
1706 {
1707 	BR_INPUT_SKB_CB(skb)->igmp = 0;
1708 	BR_INPUT_SKB_CB(skb)->mrouters_only = 0;
1709 
1710 	if (br->multicast_disabled)
1711 		return 0;
1712 
1713 	switch (skb->protocol) {
1714 	case htons(ETH_P_IP):
1715 		return br_multicast_ipv4_rcv(br, port, skb, vid);
1716 #if IS_ENABLED(CONFIG_IPV6)
1717 	case htons(ETH_P_IPV6):
1718 		return br_multicast_ipv6_rcv(br, port, skb, vid);
1719 #endif
1720 	}
1721 
1722 	return 0;
1723 }
1724 
1725 static void br_multicast_query_expired(struct net_bridge *br,
1726 				       struct bridge_mcast_query *query)
1727 {
1728 	spin_lock(&br->multicast_lock);
1729 	if (query->startup_sent < br->multicast_startup_query_count)
1730 		query->startup_sent++;
1731 
1732 	br_multicast_send_query(br, NULL, query);
1733 	spin_unlock(&br->multicast_lock);
1734 }
1735 
1736 static void br_ip4_multicast_query_expired(unsigned long data)
1737 {
1738 	struct net_bridge *br = (void *)data;
1739 
1740 	br_multicast_query_expired(br, &br->ip4_query);
1741 }
1742 
1743 #if IS_ENABLED(CONFIG_IPV6)
1744 static void br_ip6_multicast_query_expired(unsigned long data)
1745 {
1746 	struct net_bridge *br = (void *)data;
1747 
1748 	br_multicast_query_expired(br, &br->ip6_query);
1749 }
1750 #endif
1751 
1752 void br_multicast_init(struct net_bridge *br)
1753 {
1754 	br->hash_elasticity = 4;
1755 	br->hash_max = 512;
1756 
1757 	br->multicast_router = 1;
1758 	br->multicast_querier = 0;
1759 	br->multicast_query_use_ifaddr = 0;
1760 	br->multicast_last_member_count = 2;
1761 	br->multicast_startup_query_count = 2;
1762 
1763 	br->multicast_last_member_interval = HZ;
1764 	br->multicast_query_response_interval = 10 * HZ;
1765 	br->multicast_startup_query_interval = 125 * HZ / 4;
1766 	br->multicast_query_interval = 125 * HZ;
1767 	br->multicast_querier_interval = 255 * HZ;
1768 	br->multicast_membership_interval = 260 * HZ;
1769 
1770 	br->ip4_querier.delay_time = 0;
1771 #if IS_ENABLED(CONFIG_IPV6)
1772 	br->ip6_querier.delay_time = 0;
1773 #endif
1774 
1775 	spin_lock_init(&br->multicast_lock);
1776 	setup_timer(&br->multicast_router_timer,
1777 		    br_multicast_local_router_expired, 0);
1778 	setup_timer(&br->ip4_querier.timer, br_ip4_multicast_querier_expired,
1779 		    (unsigned long)br);
1780 	setup_timer(&br->ip4_query.timer, br_ip4_multicast_query_expired,
1781 		    (unsigned long)br);
1782 #if IS_ENABLED(CONFIG_IPV6)
1783 	setup_timer(&br->ip6_querier.timer, br_ip6_multicast_querier_expired,
1784 		    (unsigned long)br);
1785 	setup_timer(&br->ip6_query.timer, br_ip6_multicast_query_expired,
1786 		    (unsigned long)br);
1787 #endif
1788 }
1789 
1790 static void __br_multicast_open(struct net_bridge *br,
1791 				struct bridge_mcast_query *query)
1792 {
1793 	query->startup_sent = 0;
1794 
1795 	if (br->multicast_disabled)
1796 		return;
1797 
1798 	mod_timer(&query->timer, jiffies);
1799 }
1800 
1801 void br_multicast_open(struct net_bridge *br)
1802 {
1803 	__br_multicast_open(br, &br->ip4_query);
1804 #if IS_ENABLED(CONFIG_IPV6)
1805 	__br_multicast_open(br, &br->ip6_query);
1806 #endif
1807 }
1808 
1809 void br_multicast_stop(struct net_bridge *br)
1810 {
1811 	struct net_bridge_mdb_htable *mdb;
1812 	struct net_bridge_mdb_entry *mp;
1813 	struct hlist_node *n;
1814 	u32 ver;
1815 	int i;
1816 
1817 	del_timer_sync(&br->multicast_router_timer);
1818 	del_timer_sync(&br->ip4_querier.timer);
1819 	del_timer_sync(&br->ip4_query.timer);
1820 #if IS_ENABLED(CONFIG_IPV6)
1821 	del_timer_sync(&br->ip6_querier.timer);
1822 	del_timer_sync(&br->ip6_query.timer);
1823 #endif
1824 
1825 	spin_lock_bh(&br->multicast_lock);
1826 	mdb = mlock_dereference(br->mdb, br);
1827 	if (!mdb)
1828 		goto out;
1829 
1830 	br->mdb = NULL;
1831 
1832 	ver = mdb->ver;
1833 	for (i = 0; i < mdb->max; i++) {
1834 		hlist_for_each_entry_safe(mp, n, &mdb->mhash[i],
1835 					  hlist[ver]) {
1836 			del_timer(&mp->timer);
1837 			call_rcu_bh(&mp->rcu, br_multicast_free_group);
1838 		}
1839 	}
1840 
1841 	if (mdb->old) {
1842 		spin_unlock_bh(&br->multicast_lock);
1843 		rcu_barrier_bh();
1844 		spin_lock_bh(&br->multicast_lock);
1845 		WARN_ON(mdb->old);
1846 	}
1847 
1848 	mdb->old = mdb;
1849 	call_rcu_bh(&mdb->rcu, br_mdb_free);
1850 
1851 out:
1852 	spin_unlock_bh(&br->multicast_lock);
1853 }
1854 
1855 int br_multicast_set_router(struct net_bridge *br, unsigned long val)
1856 {
1857 	int err = -ENOENT;
1858 
1859 	spin_lock_bh(&br->multicast_lock);
1860 	if (!netif_running(br->dev))
1861 		goto unlock;
1862 
1863 	switch (val) {
1864 	case 0:
1865 	case 2:
1866 		del_timer(&br->multicast_router_timer);
1867 		/* fall through */
1868 	case 1:
1869 		br->multicast_router = val;
1870 		err = 0;
1871 		break;
1872 
1873 	default:
1874 		err = -EINVAL;
1875 		break;
1876 	}
1877 
1878 unlock:
1879 	spin_unlock_bh(&br->multicast_lock);
1880 
1881 	return err;
1882 }
1883 
1884 int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
1885 {
1886 	struct net_bridge *br = p->br;
1887 	int err = -ENOENT;
1888 
1889 	spin_lock(&br->multicast_lock);
1890 	if (!netif_running(br->dev) || p->state == BR_STATE_DISABLED)
1891 		goto unlock;
1892 
1893 	switch (val) {
1894 	case 0:
1895 	case 1:
1896 	case 2:
1897 		p->multicast_router = val;
1898 		err = 0;
1899 
1900 		if (val < 2 && !hlist_unhashed(&p->rlist))
1901 			hlist_del_init_rcu(&p->rlist);
1902 
1903 		if (val == 1)
1904 			break;
1905 
1906 		del_timer(&p->multicast_router_timer);
1907 
1908 		if (val == 0)
1909 			break;
1910 
1911 		br_multicast_add_router(br, p);
1912 		break;
1913 
1914 	default:
1915 		err = -EINVAL;
1916 		break;
1917 	}
1918 
1919 unlock:
1920 	spin_unlock(&br->multicast_lock);
1921 
1922 	return err;
1923 }
1924 
1925 static void br_multicast_start_querier(struct net_bridge *br,
1926 				       struct bridge_mcast_query *query)
1927 {
1928 	struct net_bridge_port *port;
1929 
1930 	__br_multicast_open(br, query);
1931 
1932 	list_for_each_entry(port, &br->port_list, list) {
1933 		if (port->state == BR_STATE_DISABLED ||
1934 		    port->state == BR_STATE_BLOCKING)
1935 			continue;
1936 
1937 		if (query == &br->ip4_query)
1938 			br_multicast_enable(&port->ip4_query);
1939 #if IS_ENABLED(CONFIG_IPV6)
1940 		else
1941 			br_multicast_enable(&port->ip6_query);
1942 #endif
1943 	}
1944 }
1945 
1946 int br_multicast_toggle(struct net_bridge *br, unsigned long val)
1947 {
1948 	int err = 0;
1949 	struct net_bridge_mdb_htable *mdb;
1950 
1951 	spin_lock_bh(&br->multicast_lock);
1952 	if (br->multicast_disabled == !val)
1953 		goto unlock;
1954 
1955 	br->multicast_disabled = !val;
1956 	if (br->multicast_disabled)
1957 		goto unlock;
1958 
1959 	if (!netif_running(br->dev))
1960 		goto unlock;
1961 
1962 	mdb = mlock_dereference(br->mdb, br);
1963 	if (mdb) {
1964 		if (mdb->old) {
1965 			err = -EEXIST;
1966 rollback:
1967 			br->multicast_disabled = !!val;
1968 			goto unlock;
1969 		}
1970 
1971 		err = br_mdb_rehash(&br->mdb, mdb->max,
1972 				    br->hash_elasticity);
1973 		if (err)
1974 			goto rollback;
1975 	}
1976 
1977 	br_multicast_start_querier(br, &br->ip4_query);
1978 #if IS_ENABLED(CONFIG_IPV6)
1979 	br_multicast_start_querier(br, &br->ip6_query);
1980 #endif
1981 
1982 unlock:
1983 	spin_unlock_bh(&br->multicast_lock);
1984 
1985 	return err;
1986 }
1987 
1988 int br_multicast_set_querier(struct net_bridge *br, unsigned long val)
1989 {
1990 	unsigned long max_delay;
1991 
1992 	val = !!val;
1993 
1994 	spin_lock_bh(&br->multicast_lock);
1995 	if (br->multicast_querier == val)
1996 		goto unlock;
1997 
1998 	br->multicast_querier = val;
1999 	if (!val)
2000 		goto unlock;
2001 
2002 	max_delay = br->multicast_query_response_interval;
2003 
2004 	if (!timer_pending(&br->ip4_querier.timer))
2005 		br->ip4_querier.delay_time = jiffies + max_delay;
2006 
2007 	br_multicast_start_querier(br, &br->ip4_query);
2008 
2009 #if IS_ENABLED(CONFIG_IPV6)
2010 	if (!timer_pending(&br->ip6_querier.timer))
2011 		br->ip6_querier.delay_time = jiffies + max_delay;
2012 
2013 	br_multicast_start_querier(br, &br->ip6_query);
2014 #endif
2015 
2016 unlock:
2017 	spin_unlock_bh(&br->multicast_lock);
2018 
2019 	return 0;
2020 }
2021 
2022 int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val)
2023 {
2024 	int err = -ENOENT;
2025 	u32 old;
2026 	struct net_bridge_mdb_htable *mdb;
2027 
2028 	spin_lock_bh(&br->multicast_lock);
2029 	if (!netif_running(br->dev))
2030 		goto unlock;
2031 
2032 	err = -EINVAL;
2033 	if (!is_power_of_2(val))
2034 		goto unlock;
2035 
2036 	mdb = mlock_dereference(br->mdb, br);
2037 	if (mdb && val < mdb->size)
2038 		goto unlock;
2039 
2040 	err = 0;
2041 
2042 	old = br->hash_max;
2043 	br->hash_max = val;
2044 
2045 	if (mdb) {
2046 		if (mdb->old) {
2047 			err = -EEXIST;
2048 rollback:
2049 			br->hash_max = old;
2050 			goto unlock;
2051 		}
2052 
2053 		err = br_mdb_rehash(&br->mdb, br->hash_max,
2054 				    br->hash_elasticity);
2055 		if (err)
2056 			goto rollback;
2057 	}
2058 
2059 unlock:
2060 	spin_unlock_bh(&br->multicast_lock);
2061 
2062 	return err;
2063 }
2064