xref: /linux/net/bridge/br_multicast.c (revision d39d0ed196aa1685bb24771e92f78633c66ac9cb)
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 defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
28 #include <net/ipv6.h>
29 #include <net/mld.h>
30 #include <net/addrconf.h>
31 #include <net/ip6_checksum.h>
32 #endif
33 
34 #include "br_private.h"
35 
36 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
37 static inline int ipv6_is_local_multicast(const struct in6_addr *addr)
38 {
39 	if (ipv6_addr_is_multicast(addr) &&
40 	    IPV6_ADDR_MC_SCOPE(addr) <= IPV6_ADDR_SCOPE_LINKLOCAL)
41 		return 1;
42 	return 0;
43 }
44 #endif
45 
46 static inline int br_ip_equal(const struct br_ip *a, const struct br_ip *b)
47 {
48 	if (a->proto != b->proto)
49 		return 0;
50 	switch (a->proto) {
51 	case htons(ETH_P_IP):
52 		return a->u.ip4 == b->u.ip4;
53 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
54 	case htons(ETH_P_IPV6):
55 		return ipv6_addr_equal(&a->u.ip6, &b->u.ip6);
56 #endif
57 	}
58 	return 0;
59 }
60 
61 static inline int __br_ip4_hash(struct net_bridge_mdb_htable *mdb, __be32 ip)
62 {
63 	return jhash_1word(mdb->secret, (__force u32)ip) & (mdb->max - 1);
64 }
65 
66 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
67 static inline int __br_ip6_hash(struct net_bridge_mdb_htable *mdb,
68 				const struct in6_addr *ip)
69 {
70 	return jhash2((__force u32 *)ip->s6_addr32, 4, 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);
80 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
81 	case htons(ETH_P_IPV6):
82 		return __br_ip6_hash(mdb, &ip->u.ip6);
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 	struct hlist_node *p;
93 
94 	hlist_for_each_entry_rcu(mp, p, &mdb->mhash[hash], hlist[mdb->ver]) {
95 		if (br_ip_equal(&mp->addr, dst))
96 			return mp;
97 	}
98 
99 	return NULL;
100 }
101 
102 static struct net_bridge_mdb_entry *br_mdb_ip_get(
103 	struct net_bridge_mdb_htable *mdb, struct br_ip *dst)
104 {
105 	if (!mdb)
106 		return NULL;
107 
108 	return __br_mdb_ip_get(mdb, dst, br_ip_hash(mdb, dst));
109 }
110 
111 static struct net_bridge_mdb_entry *br_mdb_ip4_get(
112 	struct net_bridge_mdb_htable *mdb, __be32 dst)
113 {
114 	struct br_ip br_dst;
115 
116 	br_dst.u.ip4 = dst;
117 	br_dst.proto = htons(ETH_P_IP);
118 
119 	return br_mdb_ip_get(mdb, &br_dst);
120 }
121 
122 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
123 static struct net_bridge_mdb_entry *br_mdb_ip6_get(
124 	struct net_bridge_mdb_htable *mdb, const struct in6_addr *dst)
125 {
126 	struct br_ip br_dst;
127 
128 	ipv6_addr_copy(&br_dst.u.ip6, dst);
129 	br_dst.proto = htons(ETH_P_IPV6);
130 
131 	return br_mdb_ip_get(mdb, &br_dst);
132 }
133 #endif
134 
135 struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br,
136 					struct sk_buff *skb)
137 {
138 	struct net_bridge_mdb_htable *mdb = br->mdb;
139 	struct br_ip ip;
140 
141 	if (br->multicast_disabled)
142 		return NULL;
143 
144 	if (BR_INPUT_SKB_CB(skb)->igmp)
145 		return NULL;
146 
147 	ip.proto = skb->protocol;
148 
149 	switch (skb->protocol) {
150 	case htons(ETH_P_IP):
151 		ip.u.ip4 = ip_hdr(skb)->daddr;
152 		break;
153 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
154 	case htons(ETH_P_IPV6):
155 		ipv6_addr_copy(&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 	struct hlist_node *p;
182 	int maxlen;
183 	int len;
184 	int i;
185 
186 	for (i = 0; i < old->max; i++)
187 		hlist_for_each_entry(mp, p, &old->mhash[i], hlist[old->ver])
188 			hlist_add_head(&mp->hlist[new->ver],
189 				       &new->mhash[br_ip_hash(new, &mp->addr)]);
190 
191 	if (!elasticity)
192 		return 0;
193 
194 	maxlen = 0;
195 	for (i = 0; i < new->max; i++) {
196 		len = 0;
197 		hlist_for_each_entry(mp, p, &new->mhash[i], hlist[new->ver])
198 			len++;
199 		if (len > maxlen)
200 			maxlen = len;
201 	}
202 
203 	return maxlen > elasticity ? -EINVAL : 0;
204 }
205 
206 static void br_multicast_free_pg(struct rcu_head *head)
207 {
208 	struct net_bridge_port_group *p =
209 		container_of(head, struct net_bridge_port_group, rcu);
210 
211 	kfree(p);
212 }
213 
214 static void br_multicast_free_group(struct rcu_head *head)
215 {
216 	struct net_bridge_mdb_entry *mp =
217 		container_of(head, struct net_bridge_mdb_entry, rcu);
218 
219 	kfree(mp);
220 }
221 
222 static void br_multicast_group_expired(unsigned long data)
223 {
224 	struct net_bridge_mdb_entry *mp = (void *)data;
225 	struct net_bridge *br = mp->br;
226 	struct net_bridge_mdb_htable *mdb;
227 
228 	spin_lock(&br->multicast_lock);
229 	if (!netif_running(br->dev) || timer_pending(&mp->timer))
230 		goto out;
231 
232 	if (!hlist_unhashed(&mp->mglist))
233 		hlist_del_init(&mp->mglist);
234 
235 	if (mp->ports)
236 		goto out;
237 
238 	mdb = br->mdb;
239 	hlist_del_rcu(&mp->hlist[mdb->ver]);
240 	mdb->size--;
241 
242 	del_timer(&mp->query_timer);
243 	call_rcu_bh(&mp->rcu, br_multicast_free_group);
244 
245 out:
246 	spin_unlock(&br->multicast_lock);
247 }
248 
249 static void br_multicast_del_pg(struct net_bridge *br,
250 				struct net_bridge_port_group *pg)
251 {
252 	struct net_bridge_mdb_htable *mdb = br->mdb;
253 	struct net_bridge_mdb_entry *mp;
254 	struct net_bridge_port_group *p;
255 	struct net_bridge_port_group **pp;
256 
257 	mp = br_mdb_ip_get(mdb, &pg->addr);
258 	if (WARN_ON(!mp))
259 		return;
260 
261 	for (pp = &mp->ports; (p = *pp); pp = &p->next) {
262 		if (p != pg)
263 			continue;
264 
265 		rcu_assign_pointer(*pp, p->next);
266 		hlist_del_init(&p->mglist);
267 		del_timer(&p->timer);
268 		del_timer(&p->query_timer);
269 		call_rcu_bh(&p->rcu, br_multicast_free_pg);
270 
271 		if (!mp->ports && hlist_unhashed(&mp->mglist) &&
272 		    netif_running(br->dev))
273 			mod_timer(&mp->timer, jiffies);
274 
275 		return;
276 	}
277 
278 	WARN_ON(1);
279 }
280 
281 static void br_multicast_port_group_expired(unsigned long data)
282 {
283 	struct net_bridge_port_group *pg = (void *)data;
284 	struct net_bridge *br = pg->port->br;
285 
286 	spin_lock(&br->multicast_lock);
287 	if (!netif_running(br->dev) || timer_pending(&pg->timer) ||
288 	    hlist_unhashed(&pg->mglist))
289 		goto out;
290 
291 	br_multicast_del_pg(br, pg);
292 
293 out:
294 	spin_unlock(&br->multicast_lock);
295 }
296 
297 static int br_mdb_rehash(struct net_bridge_mdb_htable **mdbp, int max,
298 			 int elasticity)
299 {
300 	struct net_bridge_mdb_htable *old = *mdbp;
301 	struct net_bridge_mdb_htable *mdb;
302 	int err;
303 
304 	mdb = kmalloc(sizeof(*mdb), GFP_ATOMIC);
305 	if (!mdb)
306 		return -ENOMEM;
307 
308 	mdb->max = max;
309 	mdb->old = old;
310 
311 	mdb->mhash = kzalloc(max * sizeof(*mdb->mhash), GFP_ATOMIC);
312 	if (!mdb->mhash) {
313 		kfree(mdb);
314 		return -ENOMEM;
315 	}
316 
317 	mdb->size = old ? old->size : 0;
318 	mdb->ver = old ? old->ver ^ 1 : 0;
319 
320 	if (!old || elasticity)
321 		get_random_bytes(&mdb->secret, sizeof(mdb->secret));
322 	else
323 		mdb->secret = old->secret;
324 
325 	if (!old)
326 		goto out;
327 
328 	err = br_mdb_copy(mdb, old, elasticity);
329 	if (err) {
330 		kfree(mdb->mhash);
331 		kfree(mdb);
332 		return err;
333 	}
334 
335 	call_rcu_bh(&mdb->rcu, br_mdb_free);
336 
337 out:
338 	rcu_assign_pointer(*mdbp, mdb);
339 
340 	return 0;
341 }
342 
343 static struct sk_buff *br_ip4_multicast_alloc_query(struct net_bridge *br,
344 						    __be32 group)
345 {
346 	struct sk_buff *skb;
347 	struct igmphdr *ih;
348 	struct ethhdr *eth;
349 	struct iphdr *iph;
350 
351 	skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*iph) +
352 						 sizeof(*ih) + 4);
353 	if (!skb)
354 		goto out;
355 
356 	skb->protocol = htons(ETH_P_IP);
357 
358 	skb_reset_mac_header(skb);
359 	eth = eth_hdr(skb);
360 
361 	memcpy(eth->h_source, br->dev->dev_addr, 6);
362 	eth->h_dest[0] = 1;
363 	eth->h_dest[1] = 0;
364 	eth->h_dest[2] = 0x5e;
365 	eth->h_dest[3] = 0;
366 	eth->h_dest[4] = 0;
367 	eth->h_dest[5] = 1;
368 	eth->h_proto = htons(ETH_P_IP);
369 	skb_put(skb, sizeof(*eth));
370 
371 	skb_set_network_header(skb, skb->len);
372 	iph = ip_hdr(skb);
373 
374 	iph->version = 4;
375 	iph->ihl = 6;
376 	iph->tos = 0xc0;
377 	iph->tot_len = htons(sizeof(*iph) + sizeof(*ih) + 4);
378 	iph->id = 0;
379 	iph->frag_off = htons(IP_DF);
380 	iph->ttl = 1;
381 	iph->protocol = IPPROTO_IGMP;
382 	iph->saddr = 0;
383 	iph->daddr = htonl(INADDR_ALLHOSTS_GROUP);
384 	((u8 *)&iph[1])[0] = IPOPT_RA;
385 	((u8 *)&iph[1])[1] = 4;
386 	((u8 *)&iph[1])[2] = 0;
387 	((u8 *)&iph[1])[3] = 0;
388 	ip_send_check(iph);
389 	skb_put(skb, 24);
390 
391 	skb_set_transport_header(skb, skb->len);
392 	ih = igmp_hdr(skb);
393 	ih->type = IGMP_HOST_MEMBERSHIP_QUERY;
394 	ih->code = (group ? br->multicast_last_member_interval :
395 			    br->multicast_query_response_interval) /
396 		   (HZ / IGMP_TIMER_SCALE);
397 	ih->group = group;
398 	ih->csum = 0;
399 	ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
400 	skb_put(skb, sizeof(*ih));
401 
402 	__skb_pull(skb, sizeof(*eth));
403 
404 out:
405 	return skb;
406 }
407 
408 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
409 static struct sk_buff *br_ip6_multicast_alloc_query(struct net_bridge *br,
410 						    struct in6_addr *group)
411 {
412 	struct sk_buff *skb;
413 	struct ipv6hdr *ip6h;
414 	struct mld_msg *mldq;
415 	struct ethhdr *eth;
416 	u8 *hopopt;
417 	unsigned long interval;
418 
419 	skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*ip6h) +
420 						 8 + sizeof(*mldq));
421 	if (!skb)
422 		goto out;
423 
424 	skb->protocol = htons(ETH_P_IPV6);
425 
426 	/* Ethernet header */
427 	skb_reset_mac_header(skb);
428 	eth = eth_hdr(skb);
429 
430 	memcpy(eth->h_source, br->dev->dev_addr, 6);
431 	ipv6_eth_mc_map(group, eth->h_dest);
432 	eth->h_proto = htons(ETH_P_IPV6);
433 	skb_put(skb, sizeof(*eth));
434 
435 	/* IPv6 header + HbH option */
436 	skb_set_network_header(skb, skb->len);
437 	ip6h = ipv6_hdr(skb);
438 
439 	*(__force __be32 *)ip6h = htonl(0x60000000);
440 	ip6h->payload_len = 8 + sizeof(*mldq);
441 	ip6h->nexthdr = IPPROTO_HOPOPTS;
442 	ip6h->hop_limit = 1;
443 	ipv6_addr_set(&ip6h->saddr, 0, 0, 0, 0);
444 	ipv6_addr_set(&ip6h->daddr, htonl(0xff020000), 0, 0, htonl(1));
445 
446 	hopopt = (u8 *)(ip6h + 1);
447 	hopopt[0] = IPPROTO_ICMPV6;		/* next hdr */
448 	hopopt[1] = 0;				/* length of HbH */
449 	hopopt[2] = IPV6_TLV_ROUTERALERT;	/* Router Alert */
450 	hopopt[3] = 2;				/* Length of RA Option */
451 	hopopt[4] = 0;				/* Type = 0x0000 (MLD) */
452 	hopopt[5] = 0;
453 	hopopt[6] = IPV6_TLV_PAD0;		/* Pad0 */
454 	hopopt[7] = IPV6_TLV_PAD0;		/* Pad0 */
455 
456 	skb_put(skb, sizeof(*ip6h) + 8);
457 
458 	/* ICMPv6 */
459 	skb_set_transport_header(skb, skb->len);
460 	mldq = (struct mld_msg *) icmp6_hdr(skb);
461 
462 	interval = ipv6_addr_any(group) ? br->multicast_last_member_interval :
463 					  br->multicast_query_response_interval;
464 
465 	mldq->mld_type = ICMPV6_MGM_QUERY;
466 	mldq->mld_code = 0;
467 	mldq->mld_cksum = 0;
468 	mldq->mld_maxdelay = htons((u16)jiffies_to_msecs(interval));
469 	mldq->mld_reserved = 0;
470 	ipv6_addr_copy(&mldq->mld_mca, group);
471 
472 	/* checksum */
473 	mldq->mld_cksum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
474 					  sizeof(*mldq), IPPROTO_ICMPV6,
475 					  csum_partial(mldq,
476 						       sizeof(*mldq), 0));
477 	skb_put(skb, sizeof(*mldq));
478 
479 	__skb_pull(skb, sizeof(*eth));
480 
481 out:
482 	return skb;
483 }
484 #endif
485 
486 static struct sk_buff *br_multicast_alloc_query(struct net_bridge *br,
487 						struct br_ip *addr)
488 {
489 	switch (addr->proto) {
490 	case htons(ETH_P_IP):
491 		return br_ip4_multicast_alloc_query(br, addr->u.ip4);
492 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
493 	case htons(ETH_P_IPV6):
494 		return br_ip6_multicast_alloc_query(br, &addr->u.ip6);
495 #endif
496 	}
497 	return NULL;
498 }
499 
500 static void br_multicast_send_group_query(struct net_bridge_mdb_entry *mp)
501 {
502 	struct net_bridge *br = mp->br;
503 	struct sk_buff *skb;
504 
505 	skb = br_multicast_alloc_query(br, &mp->addr);
506 	if (!skb)
507 		goto timer;
508 
509 	netif_rx(skb);
510 
511 timer:
512 	if (++mp->queries_sent < br->multicast_last_member_count)
513 		mod_timer(&mp->query_timer,
514 			  jiffies + br->multicast_last_member_interval);
515 }
516 
517 static void br_multicast_group_query_expired(unsigned long data)
518 {
519 	struct net_bridge_mdb_entry *mp = (void *)data;
520 	struct net_bridge *br = mp->br;
521 
522 	spin_lock(&br->multicast_lock);
523 	if (!netif_running(br->dev) || hlist_unhashed(&mp->mglist) ||
524 	    mp->queries_sent >= br->multicast_last_member_count)
525 		goto out;
526 
527 	br_multicast_send_group_query(mp);
528 
529 out:
530 	spin_unlock(&br->multicast_lock);
531 }
532 
533 static void br_multicast_send_port_group_query(struct net_bridge_port_group *pg)
534 {
535 	struct net_bridge_port *port = pg->port;
536 	struct net_bridge *br = port->br;
537 	struct sk_buff *skb;
538 
539 	skb = br_multicast_alloc_query(br, &pg->addr);
540 	if (!skb)
541 		goto timer;
542 
543 	br_deliver(port, skb);
544 
545 timer:
546 	if (++pg->queries_sent < br->multicast_last_member_count)
547 		mod_timer(&pg->query_timer,
548 			  jiffies + br->multicast_last_member_interval);
549 }
550 
551 static void br_multicast_port_group_query_expired(unsigned long data)
552 {
553 	struct net_bridge_port_group *pg = (void *)data;
554 	struct net_bridge_port *port = pg->port;
555 	struct net_bridge *br = port->br;
556 
557 	spin_lock(&br->multicast_lock);
558 	if (!netif_running(br->dev) || hlist_unhashed(&pg->mglist) ||
559 	    pg->queries_sent >= br->multicast_last_member_count)
560 		goto out;
561 
562 	br_multicast_send_port_group_query(pg);
563 
564 out:
565 	spin_unlock(&br->multicast_lock);
566 }
567 
568 static struct net_bridge_mdb_entry *br_multicast_get_group(
569 	struct net_bridge *br, struct net_bridge_port *port,
570 	struct br_ip *group, int hash)
571 {
572 	struct net_bridge_mdb_htable *mdb = br->mdb;
573 	struct net_bridge_mdb_entry *mp;
574 	struct hlist_node *p;
575 	unsigned count = 0;
576 	unsigned max;
577 	int elasticity;
578 	int err;
579 
580 	hlist_for_each_entry(mp, p, &mdb->mhash[hash], hlist[mdb->ver]) {
581 		count++;
582 		if (unlikely(br_ip_equal(group, &mp->addr)))
583 			return mp;
584 	}
585 
586 	elasticity = 0;
587 	max = mdb->max;
588 
589 	if (unlikely(count > br->hash_elasticity && count)) {
590 		if (net_ratelimit())
591 			br_info(br, "Multicast hash table "
592 				"chain limit reached: %s\n",
593 				port ? port->dev->name : br->dev->name);
594 
595 		elasticity = br->hash_elasticity;
596 	}
597 
598 	if (mdb->size >= max) {
599 		max *= 2;
600 		if (unlikely(max >= br->hash_max)) {
601 			br_warn(br, "Multicast hash table maximum "
602 				"reached, disabling snooping: %s, %d\n",
603 				port ? port->dev->name : br->dev->name, max);
604 			err = -E2BIG;
605 disable:
606 			br->multicast_disabled = 1;
607 			goto err;
608 		}
609 	}
610 
611 	if (max > mdb->max || elasticity) {
612 		if (mdb->old) {
613 			if (net_ratelimit())
614 				br_info(br, "Multicast hash table "
615 					"on fire: %s\n",
616 					port ? port->dev->name : br->dev->name);
617 			err = -EEXIST;
618 			goto err;
619 		}
620 
621 		err = br_mdb_rehash(&br->mdb, max, elasticity);
622 		if (err) {
623 			br_warn(br, "Cannot rehash multicast "
624 				"hash table, disabling snooping: %s, %d, %d\n",
625 				port ? port->dev->name : br->dev->name,
626 				mdb->size, err);
627 			goto disable;
628 		}
629 
630 		err = -EAGAIN;
631 		goto err;
632 	}
633 
634 	return NULL;
635 
636 err:
637 	mp = ERR_PTR(err);
638 	return mp;
639 }
640 
641 static struct net_bridge_mdb_entry *br_multicast_new_group(
642 	struct net_bridge *br, struct net_bridge_port *port,
643 	struct br_ip *group)
644 {
645 	struct net_bridge_mdb_htable *mdb = br->mdb;
646 	struct net_bridge_mdb_entry *mp;
647 	int hash;
648 
649 	if (!mdb) {
650 		if (br_mdb_rehash(&br->mdb, BR_HASH_SIZE, 0))
651 			return NULL;
652 		goto rehash;
653 	}
654 
655 	hash = br_ip_hash(mdb, group);
656 	mp = br_multicast_get_group(br, port, group, hash);
657 	switch (PTR_ERR(mp)) {
658 	case 0:
659 		break;
660 
661 	case -EAGAIN:
662 rehash:
663 		mdb = br->mdb;
664 		hash = br_ip_hash(mdb, group);
665 		break;
666 
667 	default:
668 		goto out;
669 	}
670 
671 	mp = kzalloc(sizeof(*mp), GFP_ATOMIC);
672 	if (unlikely(!mp))
673 		goto out;
674 
675 	mp->br = br;
676 	mp->addr = *group;
677 	setup_timer(&mp->timer, br_multicast_group_expired,
678 		    (unsigned long)mp);
679 	setup_timer(&mp->query_timer, br_multicast_group_query_expired,
680 		    (unsigned long)mp);
681 
682 	hlist_add_head_rcu(&mp->hlist[mdb->ver], &mdb->mhash[hash]);
683 	mdb->size++;
684 
685 out:
686 	return mp;
687 }
688 
689 static int br_multicast_add_group(struct net_bridge *br,
690 				  struct net_bridge_port *port,
691 				  struct br_ip *group)
692 {
693 	struct net_bridge_mdb_entry *mp;
694 	struct net_bridge_port_group *p;
695 	struct net_bridge_port_group **pp;
696 	unsigned long now = jiffies;
697 	int err;
698 
699 	spin_lock(&br->multicast_lock);
700 	if (!netif_running(br->dev) ||
701 	    (port && port->state == BR_STATE_DISABLED))
702 		goto out;
703 
704 	mp = br_multicast_new_group(br, port, group);
705 	err = PTR_ERR(mp);
706 	if (unlikely(IS_ERR(mp) || !mp))
707 		goto err;
708 
709 	if (!port) {
710 		hlist_add_head(&mp->mglist, &br->mglist);
711 		mod_timer(&mp->timer, now + br->multicast_membership_interval);
712 		goto out;
713 	}
714 
715 	for (pp = &mp->ports; (p = *pp); pp = &p->next) {
716 		if (p->port == port)
717 			goto found;
718 		if ((unsigned long)p->port < (unsigned long)port)
719 			break;
720 	}
721 
722 	p = kzalloc(sizeof(*p), GFP_ATOMIC);
723 	err = -ENOMEM;
724 	if (unlikely(!p))
725 		goto err;
726 
727 	p->addr = *group;
728 	p->port = port;
729 	p->next = *pp;
730 	hlist_add_head(&p->mglist, &port->mglist);
731 	setup_timer(&p->timer, br_multicast_port_group_expired,
732 		    (unsigned long)p);
733 	setup_timer(&p->query_timer, br_multicast_port_group_query_expired,
734 		    (unsigned long)p);
735 
736 	rcu_assign_pointer(*pp, p);
737 
738 found:
739 	mod_timer(&p->timer, now + br->multicast_membership_interval);
740 out:
741 	err = 0;
742 
743 err:
744 	spin_unlock(&br->multicast_lock);
745 	return err;
746 }
747 
748 static int br_ip4_multicast_add_group(struct net_bridge *br,
749 				      struct net_bridge_port *port,
750 				      __be32 group)
751 {
752 	struct br_ip br_group;
753 
754 	if (ipv4_is_local_multicast(group))
755 		return 0;
756 
757 	br_group.u.ip4 = group;
758 	br_group.proto = htons(ETH_P_IP);
759 
760 	return br_multicast_add_group(br, port, &br_group);
761 }
762 
763 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
764 static int br_ip6_multicast_add_group(struct net_bridge *br,
765 				      struct net_bridge_port *port,
766 				      const struct in6_addr *group)
767 {
768 	struct br_ip br_group;
769 
770 	if (ipv6_is_local_multicast(group))
771 		return 0;
772 
773 	ipv6_addr_copy(&br_group.u.ip6, group);
774 	br_group.proto = htons(ETH_P_IP);
775 
776 	return br_multicast_add_group(br, port, &br_group);
777 }
778 #endif
779 
780 static void br_multicast_router_expired(unsigned long data)
781 {
782 	struct net_bridge_port *port = (void *)data;
783 	struct net_bridge *br = port->br;
784 
785 	spin_lock(&br->multicast_lock);
786 	if (port->multicast_router != 1 ||
787 	    timer_pending(&port->multicast_router_timer) ||
788 	    hlist_unhashed(&port->rlist))
789 		goto out;
790 
791 	hlist_del_init_rcu(&port->rlist);
792 
793 out:
794 	spin_unlock(&br->multicast_lock);
795 }
796 
797 static void br_multicast_local_router_expired(unsigned long data)
798 {
799 }
800 
801 static void __br_multicast_send_query(struct net_bridge *br,
802 				      struct net_bridge_port *port,
803 				      struct br_ip *ip)
804 {
805 	struct sk_buff *skb;
806 
807 	skb = br_multicast_alloc_query(br, ip);
808 	if (!skb)
809 		return;
810 
811 	if (port) {
812 		__skb_push(skb, sizeof(struct ethhdr));
813 		skb->dev = port->dev;
814 		NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
815 			dev_queue_xmit);
816 	} else
817 		netif_rx(skb);
818 }
819 
820 static void br_multicast_send_query(struct net_bridge *br,
821 				    struct net_bridge_port *port, u32 sent)
822 {
823 	unsigned long time;
824 	struct br_ip br_group;
825 
826 	if (!netif_running(br->dev) || br->multicast_disabled ||
827 	    timer_pending(&br->multicast_querier_timer))
828 		return;
829 
830 	memset(&br_group.u, 0, sizeof(br_group.u));
831 
832 	br_group.proto = htons(ETH_P_IP);
833 	__br_multicast_send_query(br, port, &br_group);
834 
835 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
836 	br_group.proto = htons(ETH_P_IPV6);
837 	__br_multicast_send_query(br, port, &br_group);
838 #endif
839 
840 	time = jiffies;
841 	time += sent < br->multicast_startup_query_count ?
842 		br->multicast_startup_query_interval :
843 		br->multicast_query_interval;
844 	mod_timer(port ? &port->multicast_query_timer :
845 			 &br->multicast_query_timer, time);
846 }
847 
848 static void br_multicast_port_query_expired(unsigned long data)
849 {
850 	struct net_bridge_port *port = (void *)data;
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 (port->multicast_startup_queries_sent <
859 	    br->multicast_startup_query_count)
860 		port->multicast_startup_queries_sent++;
861 
862 	br_multicast_send_query(port->br, port,
863 				port->multicast_startup_queries_sent);
864 
865 out:
866 	spin_unlock(&br->multicast_lock);
867 }
868 
869 void br_multicast_add_port(struct net_bridge_port *port)
870 {
871 	port->multicast_router = 1;
872 
873 	setup_timer(&port->multicast_router_timer, br_multicast_router_expired,
874 		    (unsigned long)port);
875 	setup_timer(&port->multicast_query_timer,
876 		    br_multicast_port_query_expired, (unsigned long)port);
877 }
878 
879 void br_multicast_del_port(struct net_bridge_port *port)
880 {
881 	del_timer_sync(&port->multicast_router_timer);
882 }
883 
884 static void __br_multicast_enable_port(struct net_bridge_port *port)
885 {
886 	port->multicast_startup_queries_sent = 0;
887 
888 	if (try_to_del_timer_sync(&port->multicast_query_timer) >= 0 ||
889 	    del_timer(&port->multicast_query_timer))
890 		mod_timer(&port->multicast_query_timer, jiffies);
891 }
892 
893 void br_multicast_enable_port(struct net_bridge_port *port)
894 {
895 	struct net_bridge *br = port->br;
896 
897 	spin_lock(&br->multicast_lock);
898 	if (br->multicast_disabled || !netif_running(br->dev))
899 		goto out;
900 
901 	__br_multicast_enable_port(port);
902 
903 out:
904 	spin_unlock(&br->multicast_lock);
905 }
906 
907 void br_multicast_disable_port(struct net_bridge_port *port)
908 {
909 	struct net_bridge *br = port->br;
910 	struct net_bridge_port_group *pg;
911 	struct hlist_node *p, *n;
912 
913 	spin_lock(&br->multicast_lock);
914 	hlist_for_each_entry_safe(pg, p, n, &port->mglist, mglist)
915 		br_multicast_del_pg(br, pg);
916 
917 	if (!hlist_unhashed(&port->rlist))
918 		hlist_del_init_rcu(&port->rlist);
919 	del_timer(&port->multicast_router_timer);
920 	del_timer(&port->multicast_query_timer);
921 	spin_unlock(&br->multicast_lock);
922 }
923 
924 static int br_ip4_multicast_igmp3_report(struct net_bridge *br,
925 					 struct net_bridge_port *port,
926 					 struct sk_buff *skb)
927 {
928 	struct igmpv3_report *ih;
929 	struct igmpv3_grec *grec;
930 	int i;
931 	int len;
932 	int num;
933 	int type;
934 	int err = 0;
935 	__be32 group;
936 
937 	if (!pskb_may_pull(skb, sizeof(*ih)))
938 		return -EINVAL;
939 
940 	ih = igmpv3_report_hdr(skb);
941 	num = ntohs(ih->ngrec);
942 	len = sizeof(*ih);
943 
944 	for (i = 0; i < num; i++) {
945 		len += sizeof(*grec);
946 		if (!pskb_may_pull(skb, len))
947 			return -EINVAL;
948 
949 		grec = (void *)(skb->data + len - sizeof(*grec));
950 		group = grec->grec_mca;
951 		type = grec->grec_type;
952 
953 		len += ntohs(grec->grec_nsrcs) * 4;
954 		if (!pskb_may_pull(skb, len))
955 			return -EINVAL;
956 
957 		/* We treat this as an IGMPv2 report for now. */
958 		switch (type) {
959 		case IGMPV3_MODE_IS_INCLUDE:
960 		case IGMPV3_MODE_IS_EXCLUDE:
961 		case IGMPV3_CHANGE_TO_INCLUDE:
962 		case IGMPV3_CHANGE_TO_EXCLUDE:
963 		case IGMPV3_ALLOW_NEW_SOURCES:
964 		case IGMPV3_BLOCK_OLD_SOURCES:
965 			break;
966 
967 		default:
968 			continue;
969 		}
970 
971 		err = br_ip4_multicast_add_group(br, port, group);
972 		if (err)
973 			break;
974 	}
975 
976 	return err;
977 }
978 
979 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
980 static int br_ip6_multicast_mld2_report(struct net_bridge *br,
981 					struct net_bridge_port *port,
982 					struct sk_buff *skb)
983 {
984 	struct icmp6hdr *icmp6h;
985 	struct mld2_grec *grec;
986 	int i;
987 	int len;
988 	int num;
989 	int err = 0;
990 
991 	if (!pskb_may_pull(skb, sizeof(*icmp6h)))
992 		return -EINVAL;
993 
994 	icmp6h = icmp6_hdr(skb);
995 	num = ntohs(icmp6h->icmp6_dataun.un_data16[1]);
996 	len = sizeof(*icmp6h);
997 
998 	for (i = 0; i < num; i++) {
999 		__be16 *nsrcs, _nsrcs;
1000 
1001 		nsrcs = skb_header_pointer(skb,
1002 					   len + offsetof(struct mld2_grec,
1003 							  grec_mca),
1004 					   sizeof(_nsrcs), &_nsrcs);
1005 		if (!nsrcs)
1006 			return -EINVAL;
1007 
1008 		if (!pskb_may_pull(skb,
1009 				   len + sizeof(*grec) +
1010 				   sizeof(struct in6_addr) * (*nsrcs)))
1011 			return -EINVAL;
1012 
1013 		grec = (struct mld2_grec *)(skb->data + len);
1014 		len += sizeof(*grec) + sizeof(struct in6_addr) * (*nsrcs);
1015 
1016 		/* We treat these as MLDv1 reports for now. */
1017 		switch (grec->grec_type) {
1018 		case MLD2_MODE_IS_INCLUDE:
1019 		case MLD2_MODE_IS_EXCLUDE:
1020 		case MLD2_CHANGE_TO_INCLUDE:
1021 		case MLD2_CHANGE_TO_EXCLUDE:
1022 		case MLD2_ALLOW_NEW_SOURCES:
1023 		case MLD2_BLOCK_OLD_SOURCES:
1024 			break;
1025 
1026 		default:
1027 			continue;
1028 		}
1029 
1030 		err = br_ip6_multicast_add_group(br, port, &grec->grec_mca);
1031 		if (!err)
1032 			break;
1033 	}
1034 
1035 	return err;
1036 }
1037 #endif
1038 
1039 /*
1040  * Add port to rotuer_list
1041  *  list is maintained ordered by pointer value
1042  *  and locked by br->multicast_lock and RCU
1043  */
1044 static void br_multicast_add_router(struct net_bridge *br,
1045 				    struct net_bridge_port *port)
1046 {
1047 	struct net_bridge_port *p;
1048 	struct hlist_node *n, *slot = NULL;
1049 
1050 	hlist_for_each_entry(p, n, &br->router_list, rlist) {
1051 		if ((unsigned long) port >= (unsigned long) p)
1052 			break;
1053 		slot = n;
1054 	}
1055 
1056 	if (slot)
1057 		hlist_add_after_rcu(slot, &port->rlist);
1058 	else
1059 		hlist_add_head_rcu(&port->rlist, &br->router_list);
1060 }
1061 
1062 static void br_multicast_mark_router(struct net_bridge *br,
1063 				     struct net_bridge_port *port)
1064 {
1065 	unsigned long now = jiffies;
1066 
1067 	if (!port) {
1068 		if (br->multicast_router == 1)
1069 			mod_timer(&br->multicast_router_timer,
1070 				  now + br->multicast_querier_interval);
1071 		return;
1072 	}
1073 
1074 	if (port->multicast_router != 1)
1075 		return;
1076 
1077 	if (!hlist_unhashed(&port->rlist))
1078 		goto timer;
1079 
1080 	br_multicast_add_router(br, port);
1081 
1082 timer:
1083 	mod_timer(&port->multicast_router_timer,
1084 		  now + br->multicast_querier_interval);
1085 }
1086 
1087 static void br_multicast_query_received(struct net_bridge *br,
1088 					struct net_bridge_port *port,
1089 					int saddr)
1090 {
1091 	if (saddr)
1092 		mod_timer(&br->multicast_querier_timer,
1093 			  jiffies + br->multicast_querier_interval);
1094 	else if (timer_pending(&br->multicast_querier_timer))
1095 		return;
1096 
1097 	br_multicast_mark_router(br, port);
1098 }
1099 
1100 static int br_ip4_multicast_query(struct net_bridge *br,
1101 				  struct net_bridge_port *port,
1102 				  struct sk_buff *skb)
1103 {
1104 	struct iphdr *iph = ip_hdr(skb);
1105 	struct igmphdr *ih = igmp_hdr(skb);
1106 	struct net_bridge_mdb_entry *mp;
1107 	struct igmpv3_query *ih3;
1108 	struct net_bridge_port_group *p;
1109 	struct net_bridge_port_group **pp;
1110 	unsigned long max_delay;
1111 	unsigned long now = jiffies;
1112 	__be32 group;
1113 	int err = 0;
1114 
1115 	spin_lock(&br->multicast_lock);
1116 	if (!netif_running(br->dev) ||
1117 	    (port && port->state == BR_STATE_DISABLED))
1118 		goto out;
1119 
1120 	br_multicast_query_received(br, port, !!iph->saddr);
1121 
1122 	group = ih->group;
1123 
1124 	if (skb->len == sizeof(*ih)) {
1125 		max_delay = ih->code * (HZ / IGMP_TIMER_SCALE);
1126 
1127 		if (!max_delay) {
1128 			max_delay = 10 * HZ;
1129 			group = 0;
1130 		}
1131 	} else {
1132 		if (!pskb_may_pull(skb, sizeof(struct igmpv3_query))) {
1133 			err = -EINVAL;
1134 			goto out;
1135 		}
1136 
1137 		ih3 = igmpv3_query_hdr(skb);
1138 		if (ih3->nsrcs)
1139 			goto out;
1140 
1141 		max_delay = ih3->code ?
1142 			    IGMPV3_MRC(ih3->code) * (HZ / IGMP_TIMER_SCALE) : 1;
1143 	}
1144 
1145 	if (!group)
1146 		goto out;
1147 
1148 	mp = br_mdb_ip4_get(br->mdb, group);
1149 	if (!mp)
1150 		goto out;
1151 
1152 	max_delay *= br->multicast_last_member_count;
1153 
1154 	if (!hlist_unhashed(&mp->mglist) &&
1155 	    (timer_pending(&mp->timer) ?
1156 	     time_after(mp->timer.expires, now + max_delay) :
1157 	     try_to_del_timer_sync(&mp->timer) >= 0))
1158 		mod_timer(&mp->timer, now + max_delay);
1159 
1160 	for (pp = &mp->ports; (p = *pp); pp = &p->next) {
1161 		if (timer_pending(&p->timer) ?
1162 		    time_after(p->timer.expires, now + max_delay) :
1163 		    try_to_del_timer_sync(&p->timer) >= 0)
1164 			mod_timer(&mp->timer, now + max_delay);
1165 	}
1166 
1167 out:
1168 	spin_unlock(&br->multicast_lock);
1169 	return err;
1170 }
1171 
1172 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1173 static int br_ip6_multicast_query(struct net_bridge *br,
1174 				  struct net_bridge_port *port,
1175 				  struct sk_buff *skb)
1176 {
1177 	struct ipv6hdr *ip6h = ipv6_hdr(skb);
1178 	struct mld_msg *mld = (struct mld_msg *) icmp6_hdr(skb);
1179 	struct net_bridge_mdb_entry *mp;
1180 	struct mld2_query *mld2q;
1181 	struct net_bridge_port_group *p, **pp;
1182 	unsigned long max_delay;
1183 	unsigned long now = jiffies;
1184 	struct in6_addr *group = NULL;
1185 	int err = 0;
1186 
1187 	spin_lock(&br->multicast_lock);
1188 	if (!netif_running(br->dev) ||
1189 	    (port && port->state == BR_STATE_DISABLED))
1190 		goto out;
1191 
1192 	br_multicast_query_received(br, port, !ipv6_addr_any(&ip6h->saddr));
1193 
1194 	if (skb->len == sizeof(*mld)) {
1195 		if (!pskb_may_pull(skb, sizeof(*mld))) {
1196 			err = -EINVAL;
1197 			goto out;
1198 		}
1199 		mld = (struct mld_msg *) icmp6_hdr(skb);
1200 		max_delay = msecs_to_jiffies(htons(mld->mld_maxdelay));
1201 		if (max_delay)
1202 			group = &mld->mld_mca;
1203 	} else if (skb->len >= sizeof(*mld2q)) {
1204 		if (!pskb_may_pull(skb, sizeof(*mld2q))) {
1205 			err = -EINVAL;
1206 			goto out;
1207 		}
1208 		mld2q = (struct mld2_query *)icmp6_hdr(skb);
1209 		if (!mld2q->mld2q_nsrcs)
1210 			group = &mld2q->mld2q_mca;
1211 		max_delay = mld2q->mld2q_mrc ? MLDV2_MRC(mld2q->mld2q_mrc) : 1;
1212 	}
1213 
1214 	if (!group)
1215 		goto out;
1216 
1217 	mp = br_mdb_ip6_get(br->mdb, group);
1218 	if (!mp)
1219 		goto out;
1220 
1221 	max_delay *= br->multicast_last_member_count;
1222 	if (!hlist_unhashed(&mp->mglist) &&
1223 	    (timer_pending(&mp->timer) ?
1224 	     time_after(mp->timer.expires, now + max_delay) :
1225 	     try_to_del_timer_sync(&mp->timer) >= 0))
1226 		mod_timer(&mp->timer, now + max_delay);
1227 
1228 	for (pp = &mp->ports; (p = *pp); pp = &p->next) {
1229 		if (timer_pending(&p->timer) ?
1230 		    time_after(p->timer.expires, now + max_delay) :
1231 		    try_to_del_timer_sync(&p->timer) >= 0)
1232 			mod_timer(&mp->timer, now + max_delay);
1233 	}
1234 
1235 out:
1236 	spin_unlock(&br->multicast_lock);
1237 	return err;
1238 }
1239 #endif
1240 
1241 static void br_multicast_leave_group(struct net_bridge *br,
1242 				     struct net_bridge_port *port,
1243 				     struct br_ip *group)
1244 {
1245 	struct net_bridge_mdb_htable *mdb;
1246 	struct net_bridge_mdb_entry *mp;
1247 	struct net_bridge_port_group *p;
1248 	unsigned long now;
1249 	unsigned long time;
1250 
1251 	spin_lock(&br->multicast_lock);
1252 	if (!netif_running(br->dev) ||
1253 	    (port && port->state == BR_STATE_DISABLED) ||
1254 	    timer_pending(&br->multicast_querier_timer))
1255 		goto out;
1256 
1257 	mdb = br->mdb;
1258 	mp = br_mdb_ip_get(mdb, group);
1259 	if (!mp)
1260 		goto out;
1261 
1262 	now = jiffies;
1263 	time = now + br->multicast_last_member_count *
1264 		     br->multicast_last_member_interval;
1265 
1266 	if (!port) {
1267 		if (!hlist_unhashed(&mp->mglist) &&
1268 		    (timer_pending(&mp->timer) ?
1269 		     time_after(mp->timer.expires, time) :
1270 		     try_to_del_timer_sync(&mp->timer) >= 0)) {
1271 			mod_timer(&mp->timer, time);
1272 
1273 			mp->queries_sent = 0;
1274 			mod_timer(&mp->query_timer, now);
1275 		}
1276 
1277 		goto out;
1278 	}
1279 
1280 	for (p = mp->ports; p; p = p->next) {
1281 		if (p->port != port)
1282 			continue;
1283 
1284 		if (!hlist_unhashed(&p->mglist) &&
1285 		    (timer_pending(&p->timer) ?
1286 		     time_after(p->timer.expires, time) :
1287 		     try_to_del_timer_sync(&p->timer) >= 0)) {
1288 			mod_timer(&p->timer, time);
1289 
1290 			p->queries_sent = 0;
1291 			mod_timer(&p->query_timer, now);
1292 		}
1293 
1294 		break;
1295 	}
1296 
1297 out:
1298 	spin_unlock(&br->multicast_lock);
1299 }
1300 
1301 static void br_ip4_multicast_leave_group(struct net_bridge *br,
1302 					 struct net_bridge_port *port,
1303 					 __be32 group)
1304 {
1305 	struct br_ip br_group;
1306 
1307 	if (ipv4_is_local_multicast(group))
1308 		return;
1309 
1310 	br_group.u.ip4 = group;
1311 	br_group.proto = htons(ETH_P_IP);
1312 
1313 	br_multicast_leave_group(br, port, &br_group);
1314 }
1315 
1316 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1317 static void br_ip6_multicast_leave_group(struct net_bridge *br,
1318 					 struct net_bridge_port *port,
1319 					 const struct in6_addr *group)
1320 {
1321 	struct br_ip br_group;
1322 
1323 	if (ipv6_is_local_multicast(group))
1324 		return;
1325 
1326 	ipv6_addr_copy(&br_group.u.ip6, group);
1327 	br_group.proto = htons(ETH_P_IPV6);
1328 
1329 	br_multicast_leave_group(br, port, &br_group);
1330 }
1331 #endif
1332 
1333 static int br_multicast_ipv4_rcv(struct net_bridge *br,
1334 				 struct net_bridge_port *port,
1335 				 struct sk_buff *skb)
1336 {
1337 	struct sk_buff *skb2 = skb;
1338 	struct iphdr *iph;
1339 	struct igmphdr *ih;
1340 	unsigned len;
1341 	unsigned offset;
1342 	int err;
1343 
1344 	/* We treat OOM as packet loss for now. */
1345 	if (!pskb_may_pull(skb, sizeof(*iph)))
1346 		return -EINVAL;
1347 
1348 	iph = ip_hdr(skb);
1349 
1350 	if (iph->ihl < 5 || iph->version != 4)
1351 		return -EINVAL;
1352 
1353 	if (!pskb_may_pull(skb, ip_hdrlen(skb)))
1354 		return -EINVAL;
1355 
1356 	iph = ip_hdr(skb);
1357 
1358 	if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1359 		return -EINVAL;
1360 
1361 	if (iph->protocol != IPPROTO_IGMP)
1362 		return 0;
1363 
1364 	len = ntohs(iph->tot_len);
1365 	if (skb->len < len || len < ip_hdrlen(skb))
1366 		return -EINVAL;
1367 
1368 	if (skb->len > len) {
1369 		skb2 = skb_clone(skb, GFP_ATOMIC);
1370 		if (!skb2)
1371 			return -ENOMEM;
1372 
1373 		err = pskb_trim_rcsum(skb2, len);
1374 		if (err)
1375 			goto err_out;
1376 	}
1377 
1378 	len -= ip_hdrlen(skb2);
1379 	offset = skb_network_offset(skb2) + ip_hdrlen(skb2);
1380 	__skb_pull(skb2, offset);
1381 	skb_reset_transport_header(skb2);
1382 
1383 	err = -EINVAL;
1384 	if (!pskb_may_pull(skb2, sizeof(*ih)))
1385 		goto out;
1386 
1387 	switch (skb2->ip_summed) {
1388 	case CHECKSUM_COMPLETE:
1389 		if (!csum_fold(skb2->csum))
1390 			break;
1391 		/* fall through */
1392 	case CHECKSUM_NONE:
1393 		skb2->csum = 0;
1394 		if (skb_checksum_complete(skb2))
1395 			goto out;
1396 	}
1397 
1398 	err = 0;
1399 
1400 	BR_INPUT_SKB_CB(skb)->igmp = 1;
1401 	ih = igmp_hdr(skb2);
1402 
1403 	switch (ih->type) {
1404 	case IGMP_HOST_MEMBERSHIP_REPORT:
1405 	case IGMPV2_HOST_MEMBERSHIP_REPORT:
1406 		BR_INPUT_SKB_CB(skb2)->mrouters_only = 1;
1407 		err = br_ip4_multicast_add_group(br, port, ih->group);
1408 		break;
1409 	case IGMPV3_HOST_MEMBERSHIP_REPORT:
1410 		err = br_ip4_multicast_igmp3_report(br, port, skb2);
1411 		break;
1412 	case IGMP_HOST_MEMBERSHIP_QUERY:
1413 		err = br_ip4_multicast_query(br, port, skb2);
1414 		break;
1415 	case IGMP_HOST_LEAVE_MESSAGE:
1416 		br_ip4_multicast_leave_group(br, port, ih->group);
1417 		break;
1418 	}
1419 
1420 out:
1421 	__skb_push(skb2, offset);
1422 err_out:
1423 	if (skb2 != skb)
1424 		kfree_skb(skb2);
1425 	return err;
1426 }
1427 
1428 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1429 static int br_multicast_ipv6_rcv(struct net_bridge *br,
1430 				 struct net_bridge_port *port,
1431 				 struct sk_buff *skb)
1432 {
1433 	struct sk_buff *skb2 = skb;
1434 	struct ipv6hdr *ip6h;
1435 	struct icmp6hdr *icmp6h;
1436 	u8 nexthdr;
1437 	unsigned len;
1438 	int offset;
1439 	int err;
1440 
1441 	if (!pskb_may_pull(skb, sizeof(*ip6h)))
1442 		return -EINVAL;
1443 
1444 	ip6h = ipv6_hdr(skb);
1445 
1446 	/*
1447 	 * We're interested in MLD messages only.
1448 	 *  - Version is 6
1449 	 *  - MLD has always Router Alert hop-by-hop option
1450 	 *  - But we do not support jumbrograms.
1451 	 */
1452 	if (ip6h->version != 6 ||
1453 	    ip6h->nexthdr != IPPROTO_HOPOPTS ||
1454 	    ip6h->payload_len == 0)
1455 		return 0;
1456 
1457 	len = ntohs(ip6h->payload_len);
1458 	if (skb->len < len)
1459 		return -EINVAL;
1460 
1461 	nexthdr = ip6h->nexthdr;
1462 	offset = ipv6_skip_exthdr(skb, sizeof(*ip6h), &nexthdr);
1463 
1464 	if (offset < 0 || nexthdr != IPPROTO_ICMPV6)
1465 		return 0;
1466 
1467 	/* Okay, we found ICMPv6 header */
1468 	skb2 = skb_clone(skb, GFP_ATOMIC);
1469 	if (!skb2)
1470 		return -ENOMEM;
1471 
1472 	len -= offset - skb_network_offset(skb2);
1473 
1474 	__skb_pull(skb2, offset);
1475 	skb_reset_transport_header(skb2);
1476 
1477 	err = -EINVAL;
1478 	if (!pskb_may_pull(skb2, sizeof(*icmp6h)))
1479 		goto out;
1480 
1481 	icmp6h = icmp6_hdr(skb2);
1482 
1483 	switch (icmp6h->icmp6_type) {
1484 	case ICMPV6_MGM_QUERY:
1485 	case ICMPV6_MGM_REPORT:
1486 	case ICMPV6_MGM_REDUCTION:
1487 	case ICMPV6_MLD2_REPORT:
1488 		break;
1489 	default:
1490 		err = 0;
1491 		goto out;
1492 	}
1493 
1494 	/* Okay, we found MLD message. Check further. */
1495 	if (skb2->len > len) {
1496 		err = pskb_trim_rcsum(skb2, len);
1497 		if (err)
1498 			goto out;
1499 	}
1500 
1501 	switch (skb2->ip_summed) {
1502 	case CHECKSUM_COMPLETE:
1503 		if (!csum_fold(skb2->csum))
1504 			break;
1505 		/*FALLTHROUGH*/
1506 	case CHECKSUM_NONE:
1507 		skb2->csum = 0;
1508 		if (skb_checksum_complete(skb2))
1509 			goto out;
1510 	}
1511 
1512 	err = 0;
1513 
1514 	BR_INPUT_SKB_CB(skb)->igmp = 1;
1515 
1516 	switch (icmp6h->icmp6_type) {
1517 	case ICMPV6_MGM_REPORT:
1518 	    {
1519 		struct mld_msg *mld = (struct mld_msg *)icmp6h;
1520 		BR_INPUT_SKB_CB(skb2)->mrouters_only = 1;
1521 		err = br_ip6_multicast_add_group(br, port, &mld->mld_mca);
1522 		break;
1523 	    }
1524 	case ICMPV6_MLD2_REPORT:
1525 		err = br_ip6_multicast_mld2_report(br, port, skb2);
1526 		break;
1527 	case ICMPV6_MGM_QUERY:
1528 		err = br_ip6_multicast_query(br, port, skb2);
1529 		break;
1530 	case ICMPV6_MGM_REDUCTION:
1531 	    {
1532 		struct mld_msg *mld = (struct mld_msg *)icmp6h;
1533 		br_ip6_multicast_leave_group(br, port, &mld->mld_mca);
1534 	    }
1535 	}
1536 
1537 out:
1538 	__skb_push(skb2, offset);
1539 	if (skb2 != skb)
1540 		kfree_skb(skb2);
1541 	return err;
1542 }
1543 #endif
1544 
1545 int br_multicast_rcv(struct net_bridge *br, struct net_bridge_port *port,
1546 		     struct sk_buff *skb)
1547 {
1548 	BR_INPUT_SKB_CB(skb)->igmp = 0;
1549 	BR_INPUT_SKB_CB(skb)->mrouters_only = 0;
1550 
1551 	if (br->multicast_disabled)
1552 		return 0;
1553 
1554 	switch (skb->protocol) {
1555 	case htons(ETH_P_IP):
1556 		return br_multicast_ipv4_rcv(br, port, skb);
1557 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1558 	case htons(ETH_P_IPV6):
1559 		return br_multicast_ipv6_rcv(br, port, skb);
1560 #endif
1561 	}
1562 
1563 	return 0;
1564 }
1565 
1566 static void br_multicast_query_expired(unsigned long data)
1567 {
1568 	struct net_bridge *br = (void *)data;
1569 
1570 	spin_lock(&br->multicast_lock);
1571 	if (br->multicast_startup_queries_sent <
1572 	    br->multicast_startup_query_count)
1573 		br->multicast_startup_queries_sent++;
1574 
1575 	br_multicast_send_query(br, NULL, br->multicast_startup_queries_sent);
1576 
1577 	spin_unlock(&br->multicast_lock);
1578 }
1579 
1580 void br_multicast_init(struct net_bridge *br)
1581 {
1582 	br->hash_elasticity = 4;
1583 	br->hash_max = 512;
1584 
1585 	br->multicast_router = 1;
1586 	br->multicast_last_member_count = 2;
1587 	br->multicast_startup_query_count = 2;
1588 
1589 	br->multicast_last_member_interval = HZ;
1590 	br->multicast_query_response_interval = 10 * HZ;
1591 	br->multicast_startup_query_interval = 125 * HZ / 4;
1592 	br->multicast_query_interval = 125 * HZ;
1593 	br->multicast_querier_interval = 255 * HZ;
1594 	br->multicast_membership_interval = 260 * HZ;
1595 
1596 	spin_lock_init(&br->multicast_lock);
1597 	setup_timer(&br->multicast_router_timer,
1598 		    br_multicast_local_router_expired, 0);
1599 	setup_timer(&br->multicast_querier_timer,
1600 		    br_multicast_local_router_expired, 0);
1601 	setup_timer(&br->multicast_query_timer, br_multicast_query_expired,
1602 		    (unsigned long)br);
1603 }
1604 
1605 void br_multicast_open(struct net_bridge *br)
1606 {
1607 	br->multicast_startup_queries_sent = 0;
1608 
1609 	if (br->multicast_disabled)
1610 		return;
1611 
1612 	mod_timer(&br->multicast_query_timer, jiffies);
1613 }
1614 
1615 void br_multicast_stop(struct net_bridge *br)
1616 {
1617 	struct net_bridge_mdb_htable *mdb;
1618 	struct net_bridge_mdb_entry *mp;
1619 	struct hlist_node *p, *n;
1620 	u32 ver;
1621 	int i;
1622 
1623 	del_timer_sync(&br->multicast_router_timer);
1624 	del_timer_sync(&br->multicast_querier_timer);
1625 	del_timer_sync(&br->multicast_query_timer);
1626 
1627 	spin_lock_bh(&br->multicast_lock);
1628 	mdb = br->mdb;
1629 	if (!mdb)
1630 		goto out;
1631 
1632 	br->mdb = NULL;
1633 
1634 	ver = mdb->ver;
1635 	for (i = 0; i < mdb->max; i++) {
1636 		hlist_for_each_entry_safe(mp, p, n, &mdb->mhash[i],
1637 					  hlist[ver]) {
1638 			del_timer(&mp->timer);
1639 			del_timer(&mp->query_timer);
1640 			call_rcu_bh(&mp->rcu, br_multicast_free_group);
1641 		}
1642 	}
1643 
1644 	if (mdb->old) {
1645 		spin_unlock_bh(&br->multicast_lock);
1646 		rcu_barrier_bh();
1647 		spin_lock_bh(&br->multicast_lock);
1648 		WARN_ON(mdb->old);
1649 	}
1650 
1651 	mdb->old = mdb;
1652 	call_rcu_bh(&mdb->rcu, br_mdb_free);
1653 
1654 out:
1655 	spin_unlock_bh(&br->multicast_lock);
1656 }
1657 
1658 int br_multicast_set_router(struct net_bridge *br, unsigned long val)
1659 {
1660 	int err = -ENOENT;
1661 
1662 	spin_lock_bh(&br->multicast_lock);
1663 	if (!netif_running(br->dev))
1664 		goto unlock;
1665 
1666 	switch (val) {
1667 	case 0:
1668 	case 2:
1669 		del_timer(&br->multicast_router_timer);
1670 		/* fall through */
1671 	case 1:
1672 		br->multicast_router = val;
1673 		err = 0;
1674 		break;
1675 
1676 	default:
1677 		err = -EINVAL;
1678 		break;
1679 	}
1680 
1681 unlock:
1682 	spin_unlock_bh(&br->multicast_lock);
1683 
1684 	return err;
1685 }
1686 
1687 int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
1688 {
1689 	struct net_bridge *br = p->br;
1690 	int err = -ENOENT;
1691 
1692 	spin_lock(&br->multicast_lock);
1693 	if (!netif_running(br->dev) || p->state == BR_STATE_DISABLED)
1694 		goto unlock;
1695 
1696 	switch (val) {
1697 	case 0:
1698 	case 1:
1699 	case 2:
1700 		p->multicast_router = val;
1701 		err = 0;
1702 
1703 		if (val < 2 && !hlist_unhashed(&p->rlist))
1704 			hlist_del_init_rcu(&p->rlist);
1705 
1706 		if (val == 1)
1707 			break;
1708 
1709 		del_timer(&p->multicast_router_timer);
1710 
1711 		if (val == 0)
1712 			break;
1713 
1714 		br_multicast_add_router(br, p);
1715 		break;
1716 
1717 	default:
1718 		err = -EINVAL;
1719 		break;
1720 	}
1721 
1722 unlock:
1723 	spin_unlock(&br->multicast_lock);
1724 
1725 	return err;
1726 }
1727 
1728 int br_multicast_toggle(struct net_bridge *br, unsigned long val)
1729 {
1730 	struct net_bridge_port *port;
1731 	int err = 0;
1732 
1733 	spin_lock(&br->multicast_lock);
1734 	if (br->multicast_disabled == !val)
1735 		goto unlock;
1736 
1737 	br->multicast_disabled = !val;
1738 	if (br->multicast_disabled)
1739 		goto unlock;
1740 
1741 	if (!netif_running(br->dev))
1742 		goto unlock;
1743 
1744 	if (br->mdb) {
1745 		if (br->mdb->old) {
1746 			err = -EEXIST;
1747 rollback:
1748 			br->multicast_disabled = !!val;
1749 			goto unlock;
1750 		}
1751 
1752 		err = br_mdb_rehash(&br->mdb, br->mdb->max,
1753 				    br->hash_elasticity);
1754 		if (err)
1755 			goto rollback;
1756 	}
1757 
1758 	br_multicast_open(br);
1759 	list_for_each_entry(port, &br->port_list, list) {
1760 		if (port->state == BR_STATE_DISABLED ||
1761 		    port->state == BR_STATE_BLOCKING)
1762 			continue;
1763 
1764 		__br_multicast_enable_port(port);
1765 	}
1766 
1767 unlock:
1768 	spin_unlock(&br->multicast_lock);
1769 
1770 	return err;
1771 }
1772 
1773 int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val)
1774 {
1775 	int err = -ENOENT;
1776 	u32 old;
1777 
1778 	spin_lock(&br->multicast_lock);
1779 	if (!netif_running(br->dev))
1780 		goto unlock;
1781 
1782 	err = -EINVAL;
1783 	if (!is_power_of_2(val))
1784 		goto unlock;
1785 	if (br->mdb && val < br->mdb->size)
1786 		goto unlock;
1787 
1788 	err = 0;
1789 
1790 	old = br->hash_max;
1791 	br->hash_max = val;
1792 
1793 	if (br->mdb) {
1794 		if (br->mdb->old) {
1795 			err = -EEXIST;
1796 rollback:
1797 			br->hash_max = old;
1798 			goto unlock;
1799 		}
1800 
1801 		err = br_mdb_rehash(&br->mdb, br->hash_max,
1802 				    br->hash_elasticity);
1803 		if (err)
1804 			goto rollback;
1805 	}
1806 
1807 unlock:
1808 	spin_unlock(&br->multicast_lock);
1809 
1810 	return err;
1811 }
1812