xref: /openbmc/linux/net/bridge/br_multicast.c (revision 97da55fc)
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 <net/ip.h>
27 #if IS_ENABLED(CONFIG_IPV6)
28 #include <net/ipv6.h>
29 #include <net/mld.h>
30 #include <net/ip6_checksum.h>
31 #endif
32 
33 #include "br_private.h"
34 
35 static void br_multicast_start_querier(struct net_bridge *br);
36 unsigned int br_mdb_rehash_seq;
37 
38 static inline int br_ip_equal(const struct br_ip *a, const struct br_ip *b)
39 {
40 	if (a->proto != b->proto)
41 		return 0;
42 	if (a->vid != b->vid)
43 		return 0;
44 	switch (a->proto) {
45 	case htons(ETH_P_IP):
46 		return a->u.ip4 == b->u.ip4;
47 #if IS_ENABLED(CONFIG_IPV6)
48 	case htons(ETH_P_IPV6):
49 		return ipv6_addr_equal(&a->u.ip6, &b->u.ip6);
50 #endif
51 	}
52 	return 0;
53 }
54 
55 static inline int __br_ip4_hash(struct net_bridge_mdb_htable *mdb, __be32 ip,
56 				__u16 vid)
57 {
58 	return jhash_2words((__force u32)ip, vid, mdb->secret) & (mdb->max - 1);
59 }
60 
61 #if IS_ENABLED(CONFIG_IPV6)
62 static inline int __br_ip6_hash(struct net_bridge_mdb_htable *mdb,
63 				const struct in6_addr *ip,
64 				__u16 vid)
65 {
66 	return jhash_2words(ipv6_addr_hash(ip), vid,
67 			    mdb->secret) & (mdb->max - 1);
68 }
69 #endif
70 
71 static inline int br_ip_hash(struct net_bridge_mdb_htable *mdb,
72 			     struct br_ip *ip)
73 {
74 	switch (ip->proto) {
75 	case htons(ETH_P_IP):
76 		return __br_ip4_hash(mdb, ip->u.ip4, ip->vid);
77 #if IS_ENABLED(CONFIG_IPV6)
78 	case htons(ETH_P_IPV6):
79 		return __br_ip6_hash(mdb, &ip->u.ip6, ip->vid);
80 #endif
81 	}
82 	return 0;
83 }
84 
85 static struct net_bridge_mdb_entry *__br_mdb_ip_get(
86 	struct net_bridge_mdb_htable *mdb, struct br_ip *dst, int hash)
87 {
88 	struct net_bridge_mdb_entry *mp;
89 
90 	hlist_for_each_entry_rcu(mp, &mdb->mhash[hash], hlist[mdb->ver]) {
91 		if (br_ip_equal(&mp->addr, dst))
92 			return mp;
93 	}
94 
95 	return NULL;
96 }
97 
98 struct net_bridge_mdb_entry *br_mdb_ip_get(struct net_bridge_mdb_htable *mdb,
99 					   struct br_ip *dst)
100 {
101 	if (!mdb)
102 		return NULL;
103 
104 	return __br_mdb_ip_get(mdb, dst, br_ip_hash(mdb, dst));
105 }
106 
107 static struct net_bridge_mdb_entry *br_mdb_ip4_get(
108 	struct net_bridge_mdb_htable *mdb, __be32 dst, __u16 vid)
109 {
110 	struct br_ip br_dst;
111 
112 	br_dst.u.ip4 = dst;
113 	br_dst.proto = htons(ETH_P_IP);
114 	br_dst.vid = vid;
115 
116 	return br_mdb_ip_get(mdb, &br_dst);
117 }
118 
119 #if IS_ENABLED(CONFIG_IPV6)
120 static struct net_bridge_mdb_entry *br_mdb_ip6_get(
121 	struct net_bridge_mdb_htable *mdb, const struct in6_addr *dst,
122 	__u16 vid)
123 {
124 	struct br_ip br_dst;
125 
126 	br_dst.u.ip6 = *dst;
127 	br_dst.proto = htons(ETH_P_IPV6);
128 	br_dst.vid = vid;
129 
130 	return br_mdb_ip_get(mdb, &br_dst);
131 }
132 #endif
133 
134 struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br,
135 					struct sk_buff *skb, u16 vid)
136 {
137 	struct net_bridge_mdb_htable *mdb = rcu_dereference(br->mdb);
138 	struct br_ip ip;
139 
140 	if (br->multicast_disabled)
141 		return NULL;
142 
143 	if (BR_INPUT_SKB_CB(skb)->igmp)
144 		return NULL;
145 
146 	ip.proto = skb->protocol;
147 	ip.vid = vid;
148 
149 	switch (skb->protocol) {
150 	case htons(ETH_P_IP):
151 		ip.u.ip4 = ip_hdr(skb)->daddr;
152 		break;
153 #if IS_ENABLED(CONFIG_IPV6)
154 	case htons(ETH_P_IPV6):
155 		ip.u.ip6 = ipv6_hdr(skb)->daddr;
156 		break;
157 #endif
158 	default:
159 		return NULL;
160 	}
161 
162 	return br_mdb_ip_get(mdb, &ip);
163 }
164 
165 static void br_mdb_free(struct rcu_head *head)
166 {
167 	struct net_bridge_mdb_htable *mdb =
168 		container_of(head, struct net_bridge_mdb_htable, rcu);
169 	struct net_bridge_mdb_htable *old = mdb->old;
170 
171 	mdb->old = NULL;
172 	kfree(old->mhash);
173 	kfree(old);
174 }
175 
176 static int br_mdb_copy(struct net_bridge_mdb_htable *new,
177 		       struct net_bridge_mdb_htable *old,
178 		       int elasticity)
179 {
180 	struct net_bridge_mdb_entry *mp;
181 	int maxlen;
182 	int len;
183 	int i;
184 
185 	for (i = 0; i < old->max; i++)
186 		hlist_for_each_entry(mp, &old->mhash[i], hlist[old->ver])
187 			hlist_add_head(&mp->hlist[new->ver],
188 				       &new->mhash[br_ip_hash(new, &mp->addr)]);
189 
190 	if (!elasticity)
191 		return 0;
192 
193 	maxlen = 0;
194 	for (i = 0; i < new->max; i++) {
195 		len = 0;
196 		hlist_for_each_entry(mp, &new->mhash[i], hlist[new->ver])
197 			len++;
198 		if (len > maxlen)
199 			maxlen = len;
200 	}
201 
202 	return maxlen > elasticity ? -EINVAL : 0;
203 }
204 
205 void br_multicast_free_pg(struct rcu_head *head)
206 {
207 	struct net_bridge_port_group *p =
208 		container_of(head, struct net_bridge_port_group, rcu);
209 
210 	kfree(p);
211 }
212 
213 static void br_multicast_free_group(struct rcu_head *head)
214 {
215 	struct net_bridge_mdb_entry *mp =
216 		container_of(head, struct net_bridge_mdb_entry, rcu);
217 
218 	kfree(mp);
219 }
220 
221 static void br_multicast_group_expired(unsigned long data)
222 {
223 	struct net_bridge_mdb_entry *mp = (void *)data;
224 	struct net_bridge *br = mp->br;
225 	struct net_bridge_mdb_htable *mdb;
226 
227 	spin_lock(&br->multicast_lock);
228 	if (!netif_running(br->dev) || timer_pending(&mp->timer))
229 		goto out;
230 
231 	mp->mglist = false;
232 
233 	if (mp->ports)
234 		goto out;
235 
236 	mdb = mlock_dereference(br->mdb, br);
237 
238 	hlist_del_rcu(&mp->hlist[mdb->ver]);
239 	mdb->size--;
240 
241 	call_rcu_bh(&mp->rcu, br_multicast_free_group);
242 
243 out:
244 	spin_unlock(&br->multicast_lock);
245 }
246 
247 static void br_multicast_del_pg(struct net_bridge *br,
248 				struct net_bridge_port_group *pg)
249 {
250 	struct net_bridge_mdb_htable *mdb;
251 	struct net_bridge_mdb_entry *mp;
252 	struct net_bridge_port_group *p;
253 	struct net_bridge_port_group __rcu **pp;
254 
255 	mdb = mlock_dereference(br->mdb, br);
256 
257 	mp = br_mdb_ip_get(mdb, &pg->addr);
258 	if (WARN_ON(!mp))
259 		return;
260 
261 	for (pp = &mp->ports;
262 	     (p = mlock_dereference(*pp, br)) != NULL;
263 	     pp = &p->next) {
264 		if (p != pg)
265 			continue;
266 
267 		rcu_assign_pointer(*pp, p->next);
268 		hlist_del_init(&p->mglist);
269 		del_timer(&p->timer);
270 		call_rcu_bh(&p->rcu, br_multicast_free_pg);
271 
272 		if (!mp->ports && !mp->mglist &&
273 		    netif_running(br->dev))
274 			mod_timer(&mp->timer, jiffies);
275 
276 		return;
277 	}
278 
279 	WARN_ON(1);
280 }
281 
282 static void br_multicast_port_group_expired(unsigned long data)
283 {
284 	struct net_bridge_port_group *pg = (void *)data;
285 	struct net_bridge *br = pg->port->br;
286 
287 	spin_lock(&br->multicast_lock);
288 	if (!netif_running(br->dev) || timer_pending(&pg->timer) ||
289 	    hlist_unhashed(&pg->mglist) || pg->state & MDB_PERMANENT)
290 		goto out;
291 
292 	br_multicast_del_pg(br, pg);
293 
294 out:
295 	spin_unlock(&br->multicast_lock);
296 }
297 
298 static int br_mdb_rehash(struct net_bridge_mdb_htable __rcu **mdbp, int max,
299 			 int elasticity)
300 {
301 	struct net_bridge_mdb_htable *old = rcu_dereference_protected(*mdbp, 1);
302 	struct net_bridge_mdb_htable *mdb;
303 	int err;
304 
305 	mdb = kmalloc(sizeof(*mdb), GFP_ATOMIC);
306 	if (!mdb)
307 		return -ENOMEM;
308 
309 	mdb->max = max;
310 	mdb->old = old;
311 
312 	mdb->mhash = kzalloc(max * sizeof(*mdb->mhash), GFP_ATOMIC);
313 	if (!mdb->mhash) {
314 		kfree(mdb);
315 		return -ENOMEM;
316 	}
317 
318 	mdb->size = old ? old->size : 0;
319 	mdb->ver = old ? old->ver ^ 1 : 0;
320 
321 	if (!old || elasticity)
322 		get_random_bytes(&mdb->secret, sizeof(mdb->secret));
323 	else
324 		mdb->secret = old->secret;
325 
326 	if (!old)
327 		goto out;
328 
329 	err = br_mdb_copy(mdb, old, elasticity);
330 	if (err) {
331 		kfree(mdb->mhash);
332 		kfree(mdb);
333 		return err;
334 	}
335 
336 	br_mdb_rehash_seq++;
337 	call_rcu_bh(&mdb->rcu, br_mdb_free);
338 
339 out:
340 	rcu_assign_pointer(*mdbp, mdb);
341 
342 	return 0;
343 }
344 
345 static struct sk_buff *br_ip4_multicast_alloc_query(struct net_bridge *br,
346 						    __be32 group)
347 {
348 	struct sk_buff *skb;
349 	struct igmphdr *ih;
350 	struct ethhdr *eth;
351 	struct iphdr *iph;
352 
353 	skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*iph) +
354 						 sizeof(*ih) + 4);
355 	if (!skb)
356 		goto out;
357 
358 	skb->protocol = htons(ETH_P_IP);
359 
360 	skb_reset_mac_header(skb);
361 	eth = eth_hdr(skb);
362 
363 	memcpy(eth->h_source, br->dev->dev_addr, 6);
364 	eth->h_dest[0] = 1;
365 	eth->h_dest[1] = 0;
366 	eth->h_dest[2] = 0x5e;
367 	eth->h_dest[3] = 0;
368 	eth->h_dest[4] = 0;
369 	eth->h_dest[5] = 1;
370 	eth->h_proto = htons(ETH_P_IP);
371 	skb_put(skb, sizeof(*eth));
372 
373 	skb_set_network_header(skb, skb->len);
374 	iph = ip_hdr(skb);
375 
376 	iph->version = 4;
377 	iph->ihl = 6;
378 	iph->tos = 0xc0;
379 	iph->tot_len = htons(sizeof(*iph) + sizeof(*ih) + 4);
380 	iph->id = 0;
381 	iph->frag_off = htons(IP_DF);
382 	iph->ttl = 1;
383 	iph->protocol = IPPROTO_IGMP;
384 	iph->saddr = 0;
385 	iph->daddr = htonl(INADDR_ALLHOSTS_GROUP);
386 	((u8 *)&iph[1])[0] = IPOPT_RA;
387 	((u8 *)&iph[1])[1] = 4;
388 	((u8 *)&iph[1])[2] = 0;
389 	((u8 *)&iph[1])[3] = 0;
390 	ip_send_check(iph);
391 	skb_put(skb, 24);
392 
393 	skb_set_transport_header(skb, skb->len);
394 	ih = igmp_hdr(skb);
395 	ih->type = IGMP_HOST_MEMBERSHIP_QUERY;
396 	ih->code = (group ? br->multicast_last_member_interval :
397 			    br->multicast_query_response_interval) /
398 		   (HZ / IGMP_TIMER_SCALE);
399 	ih->group = group;
400 	ih->csum = 0;
401 	ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
402 	skb_put(skb, sizeof(*ih));
403 
404 	__skb_pull(skb, sizeof(*eth));
405 
406 out:
407 	return skb;
408 }
409 
410 #if IS_ENABLED(CONFIG_IPV6)
411 static struct sk_buff *br_ip6_multicast_alloc_query(struct net_bridge *br,
412 						    const struct in6_addr *group)
413 {
414 	struct sk_buff *skb;
415 	struct ipv6hdr *ip6h;
416 	struct mld_msg *mldq;
417 	struct ethhdr *eth;
418 	u8 *hopopt;
419 	unsigned long interval;
420 
421 	skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*ip6h) +
422 						 8 + sizeof(*mldq));
423 	if (!skb)
424 		goto out;
425 
426 	skb->protocol = htons(ETH_P_IPV6);
427 
428 	/* Ethernet header */
429 	skb_reset_mac_header(skb);
430 	eth = eth_hdr(skb);
431 
432 	memcpy(eth->h_source, br->dev->dev_addr, 6);
433 	eth->h_proto = htons(ETH_P_IPV6);
434 	skb_put(skb, sizeof(*eth));
435 
436 	/* IPv6 header + HbH option */
437 	skb_set_network_header(skb, skb->len);
438 	ip6h = ipv6_hdr(skb);
439 
440 	*(__force __be32 *)ip6h = htonl(0x60000000);
441 	ip6h->payload_len = htons(8 + sizeof(*mldq));
442 	ip6h->nexthdr = IPPROTO_HOPOPTS;
443 	ip6h->hop_limit = 1;
444 	ipv6_addr_set(&ip6h->daddr, htonl(0xff020000), 0, 0, htonl(1));
445 	if (ipv6_dev_get_saddr(dev_net(br->dev), br->dev, &ip6h->daddr, 0,
446 			       &ip6h->saddr)) {
447 		kfree_skb(skb);
448 		return NULL;
449 	}
450 	ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest);
451 
452 	hopopt = (u8 *)(ip6h + 1);
453 	hopopt[0] = IPPROTO_ICMPV6;		/* next hdr */
454 	hopopt[1] = 0;				/* length of HbH */
455 	hopopt[2] = IPV6_TLV_ROUTERALERT;	/* Router Alert */
456 	hopopt[3] = 2;				/* Length of RA Option */
457 	hopopt[4] = 0;				/* Type = 0x0000 (MLD) */
458 	hopopt[5] = 0;
459 	hopopt[6] = IPV6_TLV_PAD1;		/* Pad1 */
460 	hopopt[7] = IPV6_TLV_PAD1;		/* Pad1 */
461 
462 	skb_put(skb, sizeof(*ip6h) + 8);
463 
464 	/* ICMPv6 */
465 	skb_set_transport_header(skb, skb->len);
466 	mldq = (struct mld_msg *) icmp6_hdr(skb);
467 
468 	interval = ipv6_addr_any(group) ? br->multicast_last_member_interval :
469 					  br->multicast_query_response_interval;
470 
471 	mldq->mld_type = ICMPV6_MGM_QUERY;
472 	mldq->mld_code = 0;
473 	mldq->mld_cksum = 0;
474 	mldq->mld_maxdelay = htons((u16)jiffies_to_msecs(interval));
475 	mldq->mld_reserved = 0;
476 	mldq->mld_mca = *group;
477 
478 	/* checksum */
479 	mldq->mld_cksum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
480 					  sizeof(*mldq), IPPROTO_ICMPV6,
481 					  csum_partial(mldq,
482 						       sizeof(*mldq), 0));
483 	skb_put(skb, sizeof(*mldq));
484 
485 	__skb_pull(skb, sizeof(*eth));
486 
487 out:
488 	return skb;
489 }
490 #endif
491 
492 static struct sk_buff *br_multicast_alloc_query(struct net_bridge *br,
493 						struct br_ip *addr)
494 {
495 	switch (addr->proto) {
496 	case htons(ETH_P_IP):
497 		return br_ip4_multicast_alloc_query(br, addr->u.ip4);
498 #if IS_ENABLED(CONFIG_IPV6)
499 	case htons(ETH_P_IPV6):
500 		return br_ip6_multicast_alloc_query(br, &addr->u.ip6);
501 #endif
502 	}
503 	return NULL;
504 }
505 
506 static struct net_bridge_mdb_entry *br_multicast_get_group(
507 	struct net_bridge *br, struct net_bridge_port *port,
508 	struct br_ip *group, int hash)
509 {
510 	struct net_bridge_mdb_htable *mdb;
511 	struct net_bridge_mdb_entry *mp;
512 	unsigned int count = 0;
513 	unsigned int max;
514 	int elasticity;
515 	int err;
516 
517 	mdb = rcu_dereference_protected(br->mdb, 1);
518 	hlist_for_each_entry(mp, &mdb->mhash[hash], hlist[mdb->ver]) {
519 		count++;
520 		if (unlikely(br_ip_equal(group, &mp->addr)))
521 			return mp;
522 	}
523 
524 	elasticity = 0;
525 	max = mdb->max;
526 
527 	if (unlikely(count > br->hash_elasticity && count)) {
528 		if (net_ratelimit())
529 			br_info(br, "Multicast hash table "
530 				"chain limit reached: %s\n",
531 				port ? port->dev->name : br->dev->name);
532 
533 		elasticity = br->hash_elasticity;
534 	}
535 
536 	if (mdb->size >= max) {
537 		max *= 2;
538 		if (unlikely(max > br->hash_max)) {
539 			br_warn(br, "Multicast hash table maximum of %d "
540 				"reached, disabling snooping: %s\n",
541 				br->hash_max,
542 				port ? port->dev->name : br->dev->name);
543 			err = -E2BIG;
544 disable:
545 			br->multicast_disabled = 1;
546 			goto err;
547 		}
548 	}
549 
550 	if (max > mdb->max || elasticity) {
551 		if (mdb->old) {
552 			if (net_ratelimit())
553 				br_info(br, "Multicast hash table "
554 					"on fire: %s\n",
555 					port ? port->dev->name : br->dev->name);
556 			err = -EEXIST;
557 			goto err;
558 		}
559 
560 		err = br_mdb_rehash(&br->mdb, max, elasticity);
561 		if (err) {
562 			br_warn(br, "Cannot rehash multicast "
563 				"hash table, disabling snooping: %s, %d, %d\n",
564 				port ? port->dev->name : br->dev->name,
565 				mdb->size, err);
566 			goto disable;
567 		}
568 
569 		err = -EAGAIN;
570 		goto err;
571 	}
572 
573 	return NULL;
574 
575 err:
576 	mp = ERR_PTR(err);
577 	return mp;
578 }
579 
580 struct net_bridge_mdb_entry *br_multicast_new_group(struct net_bridge *br,
581 	struct net_bridge_port *port, struct br_ip *group)
582 {
583 	struct net_bridge_mdb_htable *mdb;
584 	struct net_bridge_mdb_entry *mp;
585 	int hash;
586 	int err;
587 
588 	mdb = rcu_dereference_protected(br->mdb, 1);
589 	if (!mdb) {
590 		err = br_mdb_rehash(&br->mdb, BR_HASH_SIZE, 0);
591 		if (err)
592 			return ERR_PTR(err);
593 		goto rehash;
594 	}
595 
596 	hash = br_ip_hash(mdb, group);
597 	mp = br_multicast_get_group(br, port, group, hash);
598 	switch (PTR_ERR(mp)) {
599 	case 0:
600 		break;
601 
602 	case -EAGAIN:
603 rehash:
604 		mdb = rcu_dereference_protected(br->mdb, 1);
605 		hash = br_ip_hash(mdb, group);
606 		break;
607 
608 	default:
609 		goto out;
610 	}
611 
612 	mp = kzalloc(sizeof(*mp), GFP_ATOMIC);
613 	if (unlikely(!mp))
614 		return ERR_PTR(-ENOMEM);
615 
616 	mp->br = br;
617 	mp->addr = *group;
618 	setup_timer(&mp->timer, br_multicast_group_expired,
619 		    (unsigned long)mp);
620 
621 	hlist_add_head_rcu(&mp->hlist[mdb->ver], &mdb->mhash[hash]);
622 	mdb->size++;
623 
624 out:
625 	return mp;
626 }
627 
628 struct net_bridge_port_group *br_multicast_new_port_group(
629 			struct net_bridge_port *port,
630 			struct br_ip *group,
631 			struct net_bridge_port_group __rcu *next,
632 			unsigned char state)
633 {
634 	struct net_bridge_port_group *p;
635 
636 	p = kzalloc(sizeof(*p), GFP_ATOMIC);
637 	if (unlikely(!p))
638 		return NULL;
639 
640 	p->addr = *group;
641 	p->port = port;
642 	p->state = state;
643 	rcu_assign_pointer(p->next, next);
644 	hlist_add_head(&p->mglist, &port->mglist);
645 	setup_timer(&p->timer, br_multicast_port_group_expired,
646 		    (unsigned long)p);
647 	return p;
648 }
649 
650 static int br_multicast_add_group(struct net_bridge *br,
651 				  struct net_bridge_port *port,
652 				  struct br_ip *group)
653 {
654 	struct net_bridge_mdb_entry *mp;
655 	struct net_bridge_port_group *p;
656 	struct net_bridge_port_group __rcu **pp;
657 	unsigned long now = jiffies;
658 	int err;
659 
660 	spin_lock(&br->multicast_lock);
661 	if (!netif_running(br->dev) ||
662 	    (port && port->state == BR_STATE_DISABLED))
663 		goto out;
664 
665 	mp = br_multicast_new_group(br, port, group);
666 	err = PTR_ERR(mp);
667 	if (IS_ERR(mp))
668 		goto err;
669 
670 	if (!port) {
671 		mp->mglist = true;
672 		mod_timer(&mp->timer, now + br->multicast_membership_interval);
673 		goto out;
674 	}
675 
676 	for (pp = &mp->ports;
677 	     (p = mlock_dereference(*pp, br)) != NULL;
678 	     pp = &p->next) {
679 		if (p->port == port)
680 			goto found;
681 		if ((unsigned long)p->port < (unsigned long)port)
682 			break;
683 	}
684 
685 	p = br_multicast_new_port_group(port, group, *pp, MDB_TEMPORARY);
686 	if (unlikely(!p))
687 		goto err;
688 	rcu_assign_pointer(*pp, p);
689 	br_mdb_notify(br->dev, port, group, RTM_NEWMDB);
690 
691 found:
692 	mod_timer(&p->timer, now + br->multicast_membership_interval);
693 out:
694 	err = 0;
695 
696 err:
697 	spin_unlock(&br->multicast_lock);
698 	return err;
699 }
700 
701 static int br_ip4_multicast_add_group(struct net_bridge *br,
702 				      struct net_bridge_port *port,
703 				      __be32 group,
704 				      __u16 vid)
705 {
706 	struct br_ip br_group;
707 
708 	if (ipv4_is_local_multicast(group))
709 		return 0;
710 
711 	br_group.u.ip4 = group;
712 	br_group.proto = htons(ETH_P_IP);
713 	br_group.vid = vid;
714 
715 	return br_multicast_add_group(br, port, &br_group);
716 }
717 
718 #if IS_ENABLED(CONFIG_IPV6)
719 static int br_ip6_multicast_add_group(struct net_bridge *br,
720 				      struct net_bridge_port *port,
721 				      const struct in6_addr *group,
722 				      __u16 vid)
723 {
724 	struct br_ip br_group;
725 
726 	if (!ipv6_is_transient_multicast(group))
727 		return 0;
728 
729 	br_group.u.ip6 = *group;
730 	br_group.proto = htons(ETH_P_IPV6);
731 	br_group.vid = vid;
732 
733 	return br_multicast_add_group(br, port, &br_group);
734 }
735 #endif
736 
737 static void br_multicast_router_expired(unsigned long data)
738 {
739 	struct net_bridge_port *port = (void *)data;
740 	struct net_bridge *br = port->br;
741 
742 	spin_lock(&br->multicast_lock);
743 	if (port->multicast_router != 1 ||
744 	    timer_pending(&port->multicast_router_timer) ||
745 	    hlist_unhashed(&port->rlist))
746 		goto out;
747 
748 	hlist_del_init_rcu(&port->rlist);
749 
750 out:
751 	spin_unlock(&br->multicast_lock);
752 }
753 
754 static void br_multicast_local_router_expired(unsigned long data)
755 {
756 }
757 
758 static void br_multicast_querier_expired(unsigned long data)
759 {
760 	struct net_bridge *br = (void *)data;
761 
762 	spin_lock(&br->multicast_lock);
763 	if (!netif_running(br->dev) || br->multicast_disabled)
764 		goto out;
765 
766 	br_multicast_start_querier(br);
767 
768 out:
769 	spin_unlock(&br->multicast_lock);
770 }
771 
772 static void __br_multicast_send_query(struct net_bridge *br,
773 				      struct net_bridge_port *port,
774 				      struct br_ip *ip)
775 {
776 	struct sk_buff *skb;
777 
778 	skb = br_multicast_alloc_query(br, ip);
779 	if (!skb)
780 		return;
781 
782 	if (port) {
783 		__skb_push(skb, sizeof(struct ethhdr));
784 		skb->dev = port->dev;
785 		NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
786 			dev_queue_xmit);
787 	} else
788 		netif_rx(skb);
789 }
790 
791 static void br_multicast_send_query(struct net_bridge *br,
792 				    struct net_bridge_port *port, u32 sent)
793 {
794 	unsigned long time;
795 	struct br_ip br_group;
796 
797 	if (!netif_running(br->dev) || br->multicast_disabled ||
798 	    !br->multicast_querier ||
799 	    timer_pending(&br->multicast_querier_timer))
800 		return;
801 
802 	memset(&br_group.u, 0, sizeof(br_group.u));
803 
804 	br_group.proto = htons(ETH_P_IP);
805 	__br_multicast_send_query(br, port, &br_group);
806 
807 #if IS_ENABLED(CONFIG_IPV6)
808 	br_group.proto = htons(ETH_P_IPV6);
809 	__br_multicast_send_query(br, port, &br_group);
810 #endif
811 
812 	time = jiffies;
813 	time += sent < br->multicast_startup_query_count ?
814 		br->multicast_startup_query_interval :
815 		br->multicast_query_interval;
816 	mod_timer(port ? &port->multicast_query_timer :
817 			 &br->multicast_query_timer, time);
818 }
819 
820 static void br_multicast_port_query_expired(unsigned long data)
821 {
822 	struct net_bridge_port *port = (void *)data;
823 	struct net_bridge *br = port->br;
824 
825 	spin_lock(&br->multicast_lock);
826 	if (port->state == BR_STATE_DISABLED ||
827 	    port->state == BR_STATE_BLOCKING)
828 		goto out;
829 
830 	if (port->multicast_startup_queries_sent <
831 	    br->multicast_startup_query_count)
832 		port->multicast_startup_queries_sent++;
833 
834 	br_multicast_send_query(port->br, port,
835 				port->multicast_startup_queries_sent);
836 
837 out:
838 	spin_unlock(&br->multicast_lock);
839 }
840 
841 void br_multicast_add_port(struct net_bridge_port *port)
842 {
843 	port->multicast_router = 1;
844 
845 	setup_timer(&port->multicast_router_timer, br_multicast_router_expired,
846 		    (unsigned long)port);
847 	setup_timer(&port->multicast_query_timer,
848 		    br_multicast_port_query_expired, (unsigned long)port);
849 }
850 
851 void br_multicast_del_port(struct net_bridge_port *port)
852 {
853 	del_timer_sync(&port->multicast_router_timer);
854 }
855 
856 static void __br_multicast_enable_port(struct net_bridge_port *port)
857 {
858 	port->multicast_startup_queries_sent = 0;
859 
860 	if (try_to_del_timer_sync(&port->multicast_query_timer) >= 0 ||
861 	    del_timer(&port->multicast_query_timer))
862 		mod_timer(&port->multicast_query_timer, jiffies);
863 }
864 
865 void br_multicast_enable_port(struct net_bridge_port *port)
866 {
867 	struct net_bridge *br = port->br;
868 
869 	spin_lock(&br->multicast_lock);
870 	if (br->multicast_disabled || !netif_running(br->dev))
871 		goto out;
872 
873 	__br_multicast_enable_port(port);
874 
875 out:
876 	spin_unlock(&br->multicast_lock);
877 }
878 
879 void br_multicast_disable_port(struct net_bridge_port *port)
880 {
881 	struct net_bridge *br = port->br;
882 	struct net_bridge_port_group *pg;
883 	struct hlist_node *n;
884 
885 	spin_lock(&br->multicast_lock);
886 	hlist_for_each_entry_safe(pg, n, &port->mglist, mglist)
887 		br_multicast_del_pg(br, pg);
888 
889 	if (!hlist_unhashed(&port->rlist))
890 		hlist_del_init_rcu(&port->rlist);
891 	del_timer(&port->multicast_router_timer);
892 	del_timer(&port->multicast_query_timer);
893 	spin_unlock(&br->multicast_lock);
894 }
895 
896 static int br_ip4_multicast_igmp3_report(struct net_bridge *br,
897 					 struct net_bridge_port *port,
898 					 struct sk_buff *skb)
899 {
900 	struct igmpv3_report *ih;
901 	struct igmpv3_grec *grec;
902 	int i;
903 	int len;
904 	int num;
905 	int type;
906 	int err = 0;
907 	__be32 group;
908 	u16 vid = 0;
909 
910 	if (!pskb_may_pull(skb, sizeof(*ih)))
911 		return -EINVAL;
912 
913 	br_vlan_get_tag(skb, &vid);
914 	ih = igmpv3_report_hdr(skb);
915 	num = ntohs(ih->ngrec);
916 	len = sizeof(*ih);
917 
918 	for (i = 0; i < num; i++) {
919 		len += sizeof(*grec);
920 		if (!pskb_may_pull(skb, len))
921 			return -EINVAL;
922 
923 		grec = (void *)(skb->data + len - sizeof(*grec));
924 		group = grec->grec_mca;
925 		type = grec->grec_type;
926 
927 		len += ntohs(grec->grec_nsrcs) * 4;
928 		if (!pskb_may_pull(skb, len))
929 			return -EINVAL;
930 
931 		/* We treat this as an IGMPv2 report for now. */
932 		switch (type) {
933 		case IGMPV3_MODE_IS_INCLUDE:
934 		case IGMPV3_MODE_IS_EXCLUDE:
935 		case IGMPV3_CHANGE_TO_INCLUDE:
936 		case IGMPV3_CHANGE_TO_EXCLUDE:
937 		case IGMPV3_ALLOW_NEW_SOURCES:
938 		case IGMPV3_BLOCK_OLD_SOURCES:
939 			break;
940 
941 		default:
942 			continue;
943 		}
944 
945 		err = br_ip4_multicast_add_group(br, port, group, vid);
946 		if (err)
947 			break;
948 	}
949 
950 	return err;
951 }
952 
953 #if IS_ENABLED(CONFIG_IPV6)
954 static int br_ip6_multicast_mld2_report(struct net_bridge *br,
955 					struct net_bridge_port *port,
956 					struct sk_buff *skb)
957 {
958 	struct icmp6hdr *icmp6h;
959 	struct mld2_grec *grec;
960 	int i;
961 	int len;
962 	int num;
963 	int err = 0;
964 	u16 vid = 0;
965 
966 	if (!pskb_may_pull(skb, sizeof(*icmp6h)))
967 		return -EINVAL;
968 
969 	br_vlan_get_tag(skb, &vid);
970 	icmp6h = icmp6_hdr(skb);
971 	num = ntohs(icmp6h->icmp6_dataun.un_data16[1]);
972 	len = sizeof(*icmp6h);
973 
974 	for (i = 0; i < num; i++) {
975 		__be16 *nsrcs, _nsrcs;
976 
977 		nsrcs = skb_header_pointer(skb,
978 					   len + offsetof(struct mld2_grec,
979 							  grec_nsrcs),
980 					   sizeof(_nsrcs), &_nsrcs);
981 		if (!nsrcs)
982 			return -EINVAL;
983 
984 		if (!pskb_may_pull(skb,
985 				   len + sizeof(*grec) +
986 				   sizeof(struct in6_addr) * ntohs(*nsrcs)))
987 			return -EINVAL;
988 
989 		grec = (struct mld2_grec *)(skb->data + len);
990 		len += sizeof(*grec) +
991 		       sizeof(struct in6_addr) * ntohs(*nsrcs);
992 
993 		/* We treat these as MLDv1 reports for now. */
994 		switch (grec->grec_type) {
995 		case MLD2_MODE_IS_INCLUDE:
996 		case MLD2_MODE_IS_EXCLUDE:
997 		case MLD2_CHANGE_TO_INCLUDE:
998 		case MLD2_CHANGE_TO_EXCLUDE:
999 		case MLD2_ALLOW_NEW_SOURCES:
1000 		case MLD2_BLOCK_OLD_SOURCES:
1001 			break;
1002 
1003 		default:
1004 			continue;
1005 		}
1006 
1007 		err = br_ip6_multicast_add_group(br, port, &grec->grec_mca,
1008 						 vid);
1009 		if (!err)
1010 			break;
1011 	}
1012 
1013 	return err;
1014 }
1015 #endif
1016 
1017 /*
1018  * Add port to rotuer_list
1019  *  list is maintained ordered by pointer value
1020  *  and locked by br->multicast_lock and RCU
1021  */
1022 static void br_multicast_add_router(struct net_bridge *br,
1023 				    struct net_bridge_port *port)
1024 {
1025 	struct net_bridge_port *p;
1026 	struct hlist_node *slot = NULL;
1027 
1028 	hlist_for_each_entry(p, &br->router_list, rlist) {
1029 		if ((unsigned long) port >= (unsigned long) p)
1030 			break;
1031 		slot = &p->rlist;
1032 	}
1033 
1034 	if (slot)
1035 		hlist_add_after_rcu(slot, &port->rlist);
1036 	else
1037 		hlist_add_head_rcu(&port->rlist, &br->router_list);
1038 }
1039 
1040 static void br_multicast_mark_router(struct net_bridge *br,
1041 				     struct net_bridge_port *port)
1042 {
1043 	unsigned long now = jiffies;
1044 
1045 	if (!port) {
1046 		if (br->multicast_router == 1)
1047 			mod_timer(&br->multicast_router_timer,
1048 				  now + br->multicast_querier_interval);
1049 		return;
1050 	}
1051 
1052 	if (port->multicast_router != 1)
1053 		return;
1054 
1055 	if (!hlist_unhashed(&port->rlist))
1056 		goto timer;
1057 
1058 	br_multicast_add_router(br, port);
1059 
1060 timer:
1061 	mod_timer(&port->multicast_router_timer,
1062 		  now + br->multicast_querier_interval);
1063 }
1064 
1065 static void br_multicast_query_received(struct net_bridge *br,
1066 					struct net_bridge_port *port,
1067 					int saddr)
1068 {
1069 	if (saddr)
1070 		mod_timer(&br->multicast_querier_timer,
1071 			  jiffies + br->multicast_querier_interval);
1072 	else if (timer_pending(&br->multicast_querier_timer))
1073 		return;
1074 
1075 	br_multicast_mark_router(br, port);
1076 }
1077 
1078 static int br_ip4_multicast_query(struct net_bridge *br,
1079 				  struct net_bridge_port *port,
1080 				  struct sk_buff *skb)
1081 {
1082 	const struct iphdr *iph = ip_hdr(skb);
1083 	struct igmphdr *ih = igmp_hdr(skb);
1084 	struct net_bridge_mdb_entry *mp;
1085 	struct igmpv3_query *ih3;
1086 	struct net_bridge_port_group *p;
1087 	struct net_bridge_port_group __rcu **pp;
1088 	unsigned long max_delay;
1089 	unsigned long now = jiffies;
1090 	__be32 group;
1091 	int err = 0;
1092 	u16 vid = 0;
1093 
1094 	spin_lock(&br->multicast_lock);
1095 	if (!netif_running(br->dev) ||
1096 	    (port && port->state == BR_STATE_DISABLED))
1097 		goto out;
1098 
1099 	br_multicast_query_received(br, port, !!iph->saddr);
1100 
1101 	group = ih->group;
1102 
1103 	if (skb->len == sizeof(*ih)) {
1104 		max_delay = ih->code * (HZ / IGMP_TIMER_SCALE);
1105 
1106 		if (!max_delay) {
1107 			max_delay = 10 * HZ;
1108 			group = 0;
1109 		}
1110 	} else {
1111 		if (!pskb_may_pull(skb, sizeof(struct igmpv3_query))) {
1112 			err = -EINVAL;
1113 			goto out;
1114 		}
1115 
1116 		ih3 = igmpv3_query_hdr(skb);
1117 		if (ih3->nsrcs)
1118 			goto out;
1119 
1120 		max_delay = ih3->code ?
1121 			    IGMPV3_MRC(ih3->code) * (HZ / IGMP_TIMER_SCALE) : 1;
1122 	}
1123 
1124 	if (!group)
1125 		goto out;
1126 
1127 	br_vlan_get_tag(skb, &vid);
1128 	mp = br_mdb_ip4_get(mlock_dereference(br->mdb, br), group, vid);
1129 	if (!mp)
1130 		goto out;
1131 
1132 	max_delay *= br->multicast_last_member_count;
1133 
1134 	if (mp->mglist &&
1135 	    (timer_pending(&mp->timer) ?
1136 	     time_after(mp->timer.expires, now + max_delay) :
1137 	     try_to_del_timer_sync(&mp->timer) >= 0))
1138 		mod_timer(&mp->timer, now + max_delay);
1139 
1140 	for (pp = &mp->ports;
1141 	     (p = mlock_dereference(*pp, br)) != NULL;
1142 	     pp = &p->next) {
1143 		if (timer_pending(&p->timer) ?
1144 		    time_after(p->timer.expires, now + max_delay) :
1145 		    try_to_del_timer_sync(&p->timer) >= 0)
1146 			mod_timer(&p->timer, now + max_delay);
1147 	}
1148 
1149 out:
1150 	spin_unlock(&br->multicast_lock);
1151 	return err;
1152 }
1153 
1154 #if IS_ENABLED(CONFIG_IPV6)
1155 static int br_ip6_multicast_query(struct net_bridge *br,
1156 				  struct net_bridge_port *port,
1157 				  struct sk_buff *skb)
1158 {
1159 	const struct ipv6hdr *ip6h = ipv6_hdr(skb);
1160 	struct mld_msg *mld;
1161 	struct net_bridge_mdb_entry *mp;
1162 	struct mld2_query *mld2q;
1163 	struct net_bridge_port_group *p;
1164 	struct net_bridge_port_group __rcu **pp;
1165 	unsigned long max_delay;
1166 	unsigned long now = jiffies;
1167 	const struct in6_addr *group = NULL;
1168 	int err = 0;
1169 	u16 vid = 0;
1170 
1171 	spin_lock(&br->multicast_lock);
1172 	if (!netif_running(br->dev) ||
1173 	    (port && port->state == BR_STATE_DISABLED))
1174 		goto out;
1175 
1176 	br_multicast_query_received(br, port, !ipv6_addr_any(&ip6h->saddr));
1177 
1178 	if (skb->len == sizeof(*mld)) {
1179 		if (!pskb_may_pull(skb, sizeof(*mld))) {
1180 			err = -EINVAL;
1181 			goto out;
1182 		}
1183 		mld = (struct mld_msg *) icmp6_hdr(skb);
1184 		max_delay = msecs_to_jiffies(ntohs(mld->mld_maxdelay));
1185 		if (max_delay)
1186 			group = &mld->mld_mca;
1187 	} else if (skb->len >= sizeof(*mld2q)) {
1188 		if (!pskb_may_pull(skb, sizeof(*mld2q))) {
1189 			err = -EINVAL;
1190 			goto out;
1191 		}
1192 		mld2q = (struct mld2_query *)icmp6_hdr(skb);
1193 		if (!mld2q->mld2q_nsrcs)
1194 			group = &mld2q->mld2q_mca;
1195 		max_delay = mld2q->mld2q_mrc ? MLDV2_MRC(ntohs(mld2q->mld2q_mrc)) : 1;
1196 	}
1197 
1198 	if (!group)
1199 		goto out;
1200 
1201 	br_vlan_get_tag(skb, &vid);
1202 	mp = br_mdb_ip6_get(mlock_dereference(br->mdb, br), group, vid);
1203 	if (!mp)
1204 		goto out;
1205 
1206 	max_delay *= br->multicast_last_member_count;
1207 	if (mp->mglist &&
1208 	    (timer_pending(&mp->timer) ?
1209 	     time_after(mp->timer.expires, now + max_delay) :
1210 	     try_to_del_timer_sync(&mp->timer) >= 0))
1211 		mod_timer(&mp->timer, now + max_delay);
1212 
1213 	for (pp = &mp->ports;
1214 	     (p = mlock_dereference(*pp, br)) != NULL;
1215 	     pp = &p->next) {
1216 		if (timer_pending(&p->timer) ?
1217 		    time_after(p->timer.expires, now + max_delay) :
1218 		    try_to_del_timer_sync(&p->timer) >= 0)
1219 			mod_timer(&p->timer, now + max_delay);
1220 	}
1221 
1222 out:
1223 	spin_unlock(&br->multicast_lock);
1224 	return err;
1225 }
1226 #endif
1227 
1228 static void br_multicast_leave_group(struct net_bridge *br,
1229 				     struct net_bridge_port *port,
1230 				     struct br_ip *group)
1231 {
1232 	struct net_bridge_mdb_htable *mdb;
1233 	struct net_bridge_mdb_entry *mp;
1234 	struct net_bridge_port_group *p;
1235 	unsigned long now;
1236 	unsigned long time;
1237 
1238 	spin_lock(&br->multicast_lock);
1239 	if (!netif_running(br->dev) ||
1240 	    (port && port->state == BR_STATE_DISABLED) ||
1241 	    timer_pending(&br->multicast_querier_timer))
1242 		goto out;
1243 
1244 	mdb = mlock_dereference(br->mdb, br);
1245 	mp = br_mdb_ip_get(mdb, group);
1246 	if (!mp)
1247 		goto out;
1248 
1249 	if (port && (port->flags & BR_MULTICAST_FAST_LEAVE)) {
1250 		struct net_bridge_port_group __rcu **pp;
1251 
1252 		for (pp = &mp->ports;
1253 		     (p = mlock_dereference(*pp, br)) != NULL;
1254 		     pp = &p->next) {
1255 			if (p->port != port)
1256 				continue;
1257 
1258 			rcu_assign_pointer(*pp, p->next);
1259 			hlist_del_init(&p->mglist);
1260 			del_timer(&p->timer);
1261 			call_rcu_bh(&p->rcu, br_multicast_free_pg);
1262 			br_mdb_notify(br->dev, port, group, RTM_DELMDB);
1263 
1264 			if (!mp->ports && !mp->mglist &&
1265 			    netif_running(br->dev))
1266 				mod_timer(&mp->timer, jiffies);
1267 		}
1268 		goto out;
1269 	}
1270 
1271 	now = jiffies;
1272 	time = now + br->multicast_last_member_count *
1273 		     br->multicast_last_member_interval;
1274 
1275 	if (!port) {
1276 		if (mp->mglist &&
1277 		    (timer_pending(&mp->timer) ?
1278 		     time_after(mp->timer.expires, time) :
1279 		     try_to_del_timer_sync(&mp->timer) >= 0)) {
1280 			mod_timer(&mp->timer, time);
1281 		}
1282 
1283 		goto out;
1284 	}
1285 
1286 	for (p = mlock_dereference(mp->ports, br);
1287 	     p != NULL;
1288 	     p = mlock_dereference(p->next, br)) {
1289 		if (p->port != port)
1290 			continue;
1291 
1292 		if (!hlist_unhashed(&p->mglist) &&
1293 		    (timer_pending(&p->timer) ?
1294 		     time_after(p->timer.expires, time) :
1295 		     try_to_del_timer_sync(&p->timer) >= 0)) {
1296 			mod_timer(&p->timer, time);
1297 		}
1298 
1299 		break;
1300 	}
1301 
1302 out:
1303 	spin_unlock(&br->multicast_lock);
1304 }
1305 
1306 static void br_ip4_multicast_leave_group(struct net_bridge *br,
1307 					 struct net_bridge_port *port,
1308 					 __be32 group,
1309 					 __u16 vid)
1310 {
1311 	struct br_ip br_group;
1312 
1313 	if (ipv4_is_local_multicast(group))
1314 		return;
1315 
1316 	br_group.u.ip4 = group;
1317 	br_group.proto = htons(ETH_P_IP);
1318 	br_group.vid = vid;
1319 
1320 	br_multicast_leave_group(br, port, &br_group);
1321 }
1322 
1323 #if IS_ENABLED(CONFIG_IPV6)
1324 static void br_ip6_multicast_leave_group(struct net_bridge *br,
1325 					 struct net_bridge_port *port,
1326 					 const struct in6_addr *group,
1327 					 __u16 vid)
1328 {
1329 	struct br_ip br_group;
1330 
1331 	if (!ipv6_is_transient_multicast(group))
1332 		return;
1333 
1334 	br_group.u.ip6 = *group;
1335 	br_group.proto = htons(ETH_P_IPV6);
1336 	br_group.vid = vid;
1337 
1338 	br_multicast_leave_group(br, port, &br_group);
1339 }
1340 #endif
1341 
1342 static int br_multicast_ipv4_rcv(struct net_bridge *br,
1343 				 struct net_bridge_port *port,
1344 				 struct sk_buff *skb)
1345 {
1346 	struct sk_buff *skb2 = skb;
1347 	const struct iphdr *iph;
1348 	struct igmphdr *ih;
1349 	unsigned int len;
1350 	unsigned int offset;
1351 	int err;
1352 	u16 vid = 0;
1353 
1354 	/* We treat OOM as packet loss for now. */
1355 	if (!pskb_may_pull(skb, sizeof(*iph)))
1356 		return -EINVAL;
1357 
1358 	iph = ip_hdr(skb);
1359 
1360 	if (iph->ihl < 5 || iph->version != 4)
1361 		return -EINVAL;
1362 
1363 	if (!pskb_may_pull(skb, ip_hdrlen(skb)))
1364 		return -EINVAL;
1365 
1366 	iph = ip_hdr(skb);
1367 
1368 	if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1369 		return -EINVAL;
1370 
1371 	if (iph->protocol != IPPROTO_IGMP) {
1372 		if ((iph->daddr & IGMP_LOCAL_GROUP_MASK) != IGMP_LOCAL_GROUP)
1373 			BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1374 		return 0;
1375 	}
1376 
1377 	len = ntohs(iph->tot_len);
1378 	if (skb->len < len || len < ip_hdrlen(skb))
1379 		return -EINVAL;
1380 
1381 	if (skb->len > len) {
1382 		skb2 = skb_clone(skb, GFP_ATOMIC);
1383 		if (!skb2)
1384 			return -ENOMEM;
1385 
1386 		err = pskb_trim_rcsum(skb2, len);
1387 		if (err)
1388 			goto err_out;
1389 	}
1390 
1391 	len -= ip_hdrlen(skb2);
1392 	offset = skb_network_offset(skb2) + ip_hdrlen(skb2);
1393 	__skb_pull(skb2, offset);
1394 	skb_reset_transport_header(skb2);
1395 
1396 	err = -EINVAL;
1397 	if (!pskb_may_pull(skb2, sizeof(*ih)))
1398 		goto out;
1399 
1400 	switch (skb2->ip_summed) {
1401 	case CHECKSUM_COMPLETE:
1402 		if (!csum_fold(skb2->csum))
1403 			break;
1404 		/* fall through */
1405 	case CHECKSUM_NONE:
1406 		skb2->csum = 0;
1407 		if (skb_checksum_complete(skb2))
1408 			goto out;
1409 	}
1410 
1411 	err = 0;
1412 
1413 	br_vlan_get_tag(skb2, &vid);
1414 	BR_INPUT_SKB_CB(skb)->igmp = 1;
1415 	ih = igmp_hdr(skb2);
1416 
1417 	switch (ih->type) {
1418 	case IGMP_HOST_MEMBERSHIP_REPORT:
1419 	case IGMPV2_HOST_MEMBERSHIP_REPORT:
1420 		BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1421 		err = br_ip4_multicast_add_group(br, port, ih->group, vid);
1422 		break;
1423 	case IGMPV3_HOST_MEMBERSHIP_REPORT:
1424 		err = br_ip4_multicast_igmp3_report(br, port, skb2);
1425 		break;
1426 	case IGMP_HOST_MEMBERSHIP_QUERY:
1427 		err = br_ip4_multicast_query(br, port, skb2);
1428 		break;
1429 	case IGMP_HOST_LEAVE_MESSAGE:
1430 		br_ip4_multicast_leave_group(br, port, ih->group, vid);
1431 		break;
1432 	}
1433 
1434 out:
1435 	__skb_push(skb2, offset);
1436 err_out:
1437 	if (skb2 != skb)
1438 		kfree_skb(skb2);
1439 	return err;
1440 }
1441 
1442 #if IS_ENABLED(CONFIG_IPV6)
1443 static int br_multicast_ipv6_rcv(struct net_bridge *br,
1444 				 struct net_bridge_port *port,
1445 				 struct sk_buff *skb)
1446 {
1447 	struct sk_buff *skb2;
1448 	const struct ipv6hdr *ip6h;
1449 	u8 icmp6_type;
1450 	u8 nexthdr;
1451 	__be16 frag_off;
1452 	unsigned int len;
1453 	int offset;
1454 	int err;
1455 	u16 vid = 0;
1456 
1457 	if (!pskb_may_pull(skb, sizeof(*ip6h)))
1458 		return -EINVAL;
1459 
1460 	ip6h = ipv6_hdr(skb);
1461 
1462 	/*
1463 	 * We're interested in MLD messages only.
1464 	 *  - Version is 6
1465 	 *  - MLD has always Router Alert hop-by-hop option
1466 	 *  - But we do not support jumbrograms.
1467 	 */
1468 	if (ip6h->version != 6 ||
1469 	    ip6h->nexthdr != IPPROTO_HOPOPTS ||
1470 	    ip6h->payload_len == 0)
1471 		return 0;
1472 
1473 	len = ntohs(ip6h->payload_len) + sizeof(*ip6h);
1474 	if (skb->len < len)
1475 		return -EINVAL;
1476 
1477 	nexthdr = ip6h->nexthdr;
1478 	offset = ipv6_skip_exthdr(skb, sizeof(*ip6h), &nexthdr, &frag_off);
1479 
1480 	if (offset < 0 || nexthdr != IPPROTO_ICMPV6)
1481 		return 0;
1482 
1483 	/* Okay, we found ICMPv6 header */
1484 	skb2 = skb_clone(skb, GFP_ATOMIC);
1485 	if (!skb2)
1486 		return -ENOMEM;
1487 
1488 	err = -EINVAL;
1489 	if (!pskb_may_pull(skb2, offset + sizeof(struct icmp6hdr)))
1490 		goto out;
1491 
1492 	len -= offset - skb_network_offset(skb2);
1493 
1494 	__skb_pull(skb2, offset);
1495 	skb_reset_transport_header(skb2);
1496 	skb_postpull_rcsum(skb2, skb_network_header(skb2),
1497 			   skb_network_header_len(skb2));
1498 
1499 	icmp6_type = icmp6_hdr(skb2)->icmp6_type;
1500 
1501 	switch (icmp6_type) {
1502 	case ICMPV6_MGM_QUERY:
1503 	case ICMPV6_MGM_REPORT:
1504 	case ICMPV6_MGM_REDUCTION:
1505 	case ICMPV6_MLD2_REPORT:
1506 		break;
1507 	default:
1508 		err = 0;
1509 		goto out;
1510 	}
1511 
1512 	/* Okay, we found MLD message. Check further. */
1513 	if (skb2->len > len) {
1514 		err = pskb_trim_rcsum(skb2, len);
1515 		if (err)
1516 			goto out;
1517 		err = -EINVAL;
1518 	}
1519 
1520 	ip6h = ipv6_hdr(skb2);
1521 
1522 	switch (skb2->ip_summed) {
1523 	case CHECKSUM_COMPLETE:
1524 		if (!csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, skb2->len,
1525 					IPPROTO_ICMPV6, skb2->csum))
1526 			break;
1527 		/*FALLTHROUGH*/
1528 	case CHECKSUM_NONE:
1529 		skb2->csum = ~csum_unfold(csum_ipv6_magic(&ip6h->saddr,
1530 							&ip6h->daddr,
1531 							skb2->len,
1532 							IPPROTO_ICMPV6, 0));
1533 		if (__skb_checksum_complete(skb2))
1534 			goto out;
1535 	}
1536 
1537 	err = 0;
1538 
1539 	br_vlan_get_tag(skb, &vid);
1540 	BR_INPUT_SKB_CB(skb)->igmp = 1;
1541 
1542 	switch (icmp6_type) {
1543 	case ICMPV6_MGM_REPORT:
1544 	    {
1545 		struct mld_msg *mld;
1546 		if (!pskb_may_pull(skb2, sizeof(*mld))) {
1547 			err = -EINVAL;
1548 			goto out;
1549 		}
1550 		mld = (struct mld_msg *)skb_transport_header(skb2);
1551 		BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1552 		err = br_ip6_multicast_add_group(br, port, &mld->mld_mca, vid);
1553 		break;
1554 	    }
1555 	case ICMPV6_MLD2_REPORT:
1556 		err = br_ip6_multicast_mld2_report(br, port, skb2);
1557 		break;
1558 	case ICMPV6_MGM_QUERY:
1559 		err = br_ip6_multicast_query(br, port, skb2);
1560 		break;
1561 	case ICMPV6_MGM_REDUCTION:
1562 	    {
1563 		struct mld_msg *mld;
1564 		if (!pskb_may_pull(skb2, sizeof(*mld))) {
1565 			err = -EINVAL;
1566 			goto out;
1567 		}
1568 		mld = (struct mld_msg *)skb_transport_header(skb2);
1569 		br_ip6_multicast_leave_group(br, port, &mld->mld_mca, vid);
1570 	    }
1571 	}
1572 
1573 out:
1574 	kfree_skb(skb2);
1575 	return err;
1576 }
1577 #endif
1578 
1579 int br_multicast_rcv(struct net_bridge *br, struct net_bridge_port *port,
1580 		     struct sk_buff *skb)
1581 {
1582 	BR_INPUT_SKB_CB(skb)->igmp = 0;
1583 	BR_INPUT_SKB_CB(skb)->mrouters_only = 0;
1584 
1585 	if (br->multicast_disabled)
1586 		return 0;
1587 
1588 	switch (skb->protocol) {
1589 	case htons(ETH_P_IP):
1590 		return br_multicast_ipv4_rcv(br, port, skb);
1591 #if IS_ENABLED(CONFIG_IPV6)
1592 	case htons(ETH_P_IPV6):
1593 		return br_multicast_ipv6_rcv(br, port, skb);
1594 #endif
1595 	}
1596 
1597 	return 0;
1598 }
1599 
1600 static void br_multicast_query_expired(unsigned long data)
1601 {
1602 	struct net_bridge *br = (void *)data;
1603 
1604 	spin_lock(&br->multicast_lock);
1605 	if (br->multicast_startup_queries_sent <
1606 	    br->multicast_startup_query_count)
1607 		br->multicast_startup_queries_sent++;
1608 
1609 	br_multicast_send_query(br, NULL, br->multicast_startup_queries_sent);
1610 
1611 	spin_unlock(&br->multicast_lock);
1612 }
1613 
1614 void br_multicast_init(struct net_bridge *br)
1615 {
1616 	br->hash_elasticity = 4;
1617 	br->hash_max = 512;
1618 
1619 	br->multicast_router = 1;
1620 	br->multicast_querier = 0;
1621 	br->multicast_last_member_count = 2;
1622 	br->multicast_startup_query_count = 2;
1623 
1624 	br->multicast_last_member_interval = HZ;
1625 	br->multicast_query_response_interval = 10 * HZ;
1626 	br->multicast_startup_query_interval = 125 * HZ / 4;
1627 	br->multicast_query_interval = 125 * HZ;
1628 	br->multicast_querier_interval = 255 * HZ;
1629 	br->multicast_membership_interval = 260 * HZ;
1630 
1631 	spin_lock_init(&br->multicast_lock);
1632 	setup_timer(&br->multicast_router_timer,
1633 		    br_multicast_local_router_expired, 0);
1634 	setup_timer(&br->multicast_querier_timer,
1635 		    br_multicast_querier_expired, (unsigned long)br);
1636 	setup_timer(&br->multicast_query_timer, br_multicast_query_expired,
1637 		    (unsigned long)br);
1638 }
1639 
1640 void br_multicast_open(struct net_bridge *br)
1641 {
1642 	br->multicast_startup_queries_sent = 0;
1643 
1644 	if (br->multicast_disabled)
1645 		return;
1646 
1647 	mod_timer(&br->multicast_query_timer, jiffies);
1648 }
1649 
1650 void br_multicast_stop(struct net_bridge *br)
1651 {
1652 	struct net_bridge_mdb_htable *mdb;
1653 	struct net_bridge_mdb_entry *mp;
1654 	struct hlist_node *n;
1655 	u32 ver;
1656 	int i;
1657 
1658 	del_timer_sync(&br->multicast_router_timer);
1659 	del_timer_sync(&br->multicast_querier_timer);
1660 	del_timer_sync(&br->multicast_query_timer);
1661 
1662 	spin_lock_bh(&br->multicast_lock);
1663 	mdb = mlock_dereference(br->mdb, br);
1664 	if (!mdb)
1665 		goto out;
1666 
1667 	br->mdb = NULL;
1668 
1669 	ver = mdb->ver;
1670 	for (i = 0; i < mdb->max; i++) {
1671 		hlist_for_each_entry_safe(mp, n, &mdb->mhash[i],
1672 					  hlist[ver]) {
1673 			del_timer(&mp->timer);
1674 			call_rcu_bh(&mp->rcu, br_multicast_free_group);
1675 		}
1676 	}
1677 
1678 	if (mdb->old) {
1679 		spin_unlock_bh(&br->multicast_lock);
1680 		rcu_barrier_bh();
1681 		spin_lock_bh(&br->multicast_lock);
1682 		WARN_ON(mdb->old);
1683 	}
1684 
1685 	mdb->old = mdb;
1686 	call_rcu_bh(&mdb->rcu, br_mdb_free);
1687 
1688 out:
1689 	spin_unlock_bh(&br->multicast_lock);
1690 }
1691 
1692 int br_multicast_set_router(struct net_bridge *br, unsigned long val)
1693 {
1694 	int err = -ENOENT;
1695 
1696 	spin_lock_bh(&br->multicast_lock);
1697 	if (!netif_running(br->dev))
1698 		goto unlock;
1699 
1700 	switch (val) {
1701 	case 0:
1702 	case 2:
1703 		del_timer(&br->multicast_router_timer);
1704 		/* fall through */
1705 	case 1:
1706 		br->multicast_router = val;
1707 		err = 0;
1708 		break;
1709 
1710 	default:
1711 		err = -EINVAL;
1712 		break;
1713 	}
1714 
1715 unlock:
1716 	spin_unlock_bh(&br->multicast_lock);
1717 
1718 	return err;
1719 }
1720 
1721 int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
1722 {
1723 	struct net_bridge *br = p->br;
1724 	int err = -ENOENT;
1725 
1726 	spin_lock(&br->multicast_lock);
1727 	if (!netif_running(br->dev) || p->state == BR_STATE_DISABLED)
1728 		goto unlock;
1729 
1730 	switch (val) {
1731 	case 0:
1732 	case 1:
1733 	case 2:
1734 		p->multicast_router = val;
1735 		err = 0;
1736 
1737 		if (val < 2 && !hlist_unhashed(&p->rlist))
1738 			hlist_del_init_rcu(&p->rlist);
1739 
1740 		if (val == 1)
1741 			break;
1742 
1743 		del_timer(&p->multicast_router_timer);
1744 
1745 		if (val == 0)
1746 			break;
1747 
1748 		br_multicast_add_router(br, p);
1749 		break;
1750 
1751 	default:
1752 		err = -EINVAL;
1753 		break;
1754 	}
1755 
1756 unlock:
1757 	spin_unlock(&br->multicast_lock);
1758 
1759 	return err;
1760 }
1761 
1762 static void br_multicast_start_querier(struct net_bridge *br)
1763 {
1764 	struct net_bridge_port *port;
1765 
1766 	br_multicast_open(br);
1767 
1768 	list_for_each_entry(port, &br->port_list, list) {
1769 		if (port->state == BR_STATE_DISABLED ||
1770 		    port->state == BR_STATE_BLOCKING)
1771 			continue;
1772 
1773 		__br_multicast_enable_port(port);
1774 	}
1775 }
1776 
1777 int br_multicast_toggle(struct net_bridge *br, unsigned long val)
1778 {
1779 	int err = 0;
1780 	struct net_bridge_mdb_htable *mdb;
1781 
1782 	spin_lock_bh(&br->multicast_lock);
1783 	if (br->multicast_disabled == !val)
1784 		goto unlock;
1785 
1786 	br->multicast_disabled = !val;
1787 	if (br->multicast_disabled)
1788 		goto unlock;
1789 
1790 	if (!netif_running(br->dev))
1791 		goto unlock;
1792 
1793 	mdb = mlock_dereference(br->mdb, br);
1794 	if (mdb) {
1795 		if (mdb->old) {
1796 			err = -EEXIST;
1797 rollback:
1798 			br->multicast_disabled = !!val;
1799 			goto unlock;
1800 		}
1801 
1802 		err = br_mdb_rehash(&br->mdb, mdb->max,
1803 				    br->hash_elasticity);
1804 		if (err)
1805 			goto rollback;
1806 	}
1807 
1808 	br_multicast_start_querier(br);
1809 
1810 unlock:
1811 	spin_unlock_bh(&br->multicast_lock);
1812 
1813 	return err;
1814 }
1815 
1816 int br_multicast_set_querier(struct net_bridge *br, unsigned long val)
1817 {
1818 	val = !!val;
1819 
1820 	spin_lock_bh(&br->multicast_lock);
1821 	if (br->multicast_querier == val)
1822 		goto unlock;
1823 
1824 	br->multicast_querier = val;
1825 	if (val)
1826 		br_multicast_start_querier(br);
1827 
1828 unlock:
1829 	spin_unlock_bh(&br->multicast_lock);
1830 
1831 	return 0;
1832 }
1833 
1834 int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val)
1835 {
1836 	int err = -ENOENT;
1837 	u32 old;
1838 	struct net_bridge_mdb_htable *mdb;
1839 
1840 	spin_lock(&br->multicast_lock);
1841 	if (!netif_running(br->dev))
1842 		goto unlock;
1843 
1844 	err = -EINVAL;
1845 	if (!is_power_of_2(val))
1846 		goto unlock;
1847 
1848 	mdb = mlock_dereference(br->mdb, br);
1849 	if (mdb && val < mdb->size)
1850 		goto unlock;
1851 
1852 	err = 0;
1853 
1854 	old = br->hash_max;
1855 	br->hash_max = val;
1856 
1857 	if (mdb) {
1858 		if (mdb->old) {
1859 			err = -EEXIST;
1860 rollback:
1861 			br->hash_max = old;
1862 			goto unlock;
1863 		}
1864 
1865 		err = br_mdb_rehash(&br->mdb, br->hash_max,
1866 				    br->hash_elasticity);
1867 		if (err)
1868 			goto rollback;
1869 	}
1870 
1871 unlock:
1872 	spin_unlock(&br->multicast_lock);
1873 
1874 	return err;
1875 }
1876