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 #define mlock_dereference(X, br) \
37 rcu_dereference_protected(X, lockdep_is_held(&br->multicast_lock))
38
39 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
ipv6_is_transient_multicast(const struct in6_addr * addr)40 static inline int ipv6_is_transient_multicast(const struct in6_addr *addr)
41 {
42 if (ipv6_addr_is_multicast(addr) && IPV6_ADDR_MC_FLAG_TRANSIENT(addr))
43 return 1;
44 return 0;
45 }
46 #endif
47
br_ip_equal(const struct br_ip * a,const struct br_ip * b)48 static inline int br_ip_equal(const struct br_ip *a, const struct br_ip *b)
49 {
50 if (a->proto != b->proto)
51 return 0;
52 switch (a->proto) {
53 case htons(ETH_P_IP):
54 return a->u.ip4 == b->u.ip4;
55 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
56 case htons(ETH_P_IPV6):
57 return ipv6_addr_equal(&a->u.ip6, &b->u.ip6);
58 #endif
59 }
60 return 0;
61 }
62
__br_ip4_hash(struct net_bridge_mdb_htable * mdb,__be32 ip)63 static inline int __br_ip4_hash(struct net_bridge_mdb_htable *mdb, __be32 ip)
64 {
65 return jhash_1word(mdb->secret, (__force u32)ip) & (mdb->max - 1);
66 }
67
68 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
__br_ip6_hash(struct net_bridge_mdb_htable * mdb,const struct in6_addr * ip)69 static inline int __br_ip6_hash(struct net_bridge_mdb_htable *mdb,
70 const struct in6_addr *ip)
71 {
72 return jhash2((__force u32 *)ip->s6_addr32, 4, mdb->secret) & (mdb->max - 1);
73 }
74 #endif
75
br_ip_hash(struct net_bridge_mdb_htable * mdb,struct br_ip * ip)76 static inline int br_ip_hash(struct net_bridge_mdb_htable *mdb,
77 struct br_ip *ip)
78 {
79 switch (ip->proto) {
80 case htons(ETH_P_IP):
81 return __br_ip4_hash(mdb, ip->u.ip4);
82 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
83 case htons(ETH_P_IPV6):
84 return __br_ip6_hash(mdb, &ip->u.ip6);
85 #endif
86 }
87 return 0;
88 }
89
__br_mdb_ip_get(struct net_bridge_mdb_htable * mdb,struct br_ip * dst,int hash)90 static struct net_bridge_mdb_entry *__br_mdb_ip_get(
91 struct net_bridge_mdb_htable *mdb, struct br_ip *dst, int hash)
92 {
93 struct net_bridge_mdb_entry *mp;
94 struct hlist_node *p;
95
96 hlist_for_each_entry_rcu(mp, p, &mdb->mhash[hash], hlist[mdb->ver]) {
97 if (br_ip_equal(&mp->addr, dst))
98 return mp;
99 }
100
101 return NULL;
102 }
103
br_mdb_ip_get(struct net_bridge_mdb_htable * mdb,struct br_ip * dst)104 static struct net_bridge_mdb_entry *br_mdb_ip_get(
105 struct net_bridge_mdb_htable *mdb, struct br_ip *dst)
106 {
107 if (!mdb)
108 return NULL;
109
110 return __br_mdb_ip_get(mdb, dst, br_ip_hash(mdb, dst));
111 }
112
br_mdb_ip4_get(struct net_bridge_mdb_htable * mdb,__be32 dst)113 static struct net_bridge_mdb_entry *br_mdb_ip4_get(
114 struct net_bridge_mdb_htable *mdb, __be32 dst)
115 {
116 struct br_ip br_dst;
117
118 br_dst.u.ip4 = dst;
119 br_dst.proto = htons(ETH_P_IP);
120
121 return br_mdb_ip_get(mdb, &br_dst);
122 }
123
124 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
br_mdb_ip6_get(struct net_bridge_mdb_htable * mdb,const struct in6_addr * dst)125 static struct net_bridge_mdb_entry *br_mdb_ip6_get(
126 struct net_bridge_mdb_htable *mdb, const struct in6_addr *dst)
127 {
128 struct br_ip br_dst;
129
130 ipv6_addr_copy(&br_dst.u.ip6, dst);
131 br_dst.proto = htons(ETH_P_IPV6);
132
133 return br_mdb_ip_get(mdb, &br_dst);
134 }
135 #endif
136
br_mdb_get(struct net_bridge * br,struct sk_buff * skb)137 struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br,
138 struct sk_buff *skb)
139 {
140 struct net_bridge_mdb_htable *mdb = rcu_dereference(br->mdb);
141 struct br_ip ip;
142
143 if (br->multicast_disabled)
144 return NULL;
145
146 if (BR_INPUT_SKB_CB(skb)->igmp)
147 return NULL;
148
149 ip.proto = skb->protocol;
150
151 switch (skb->protocol) {
152 case htons(ETH_P_IP):
153 ip.u.ip4 = ip_hdr(skb)->daddr;
154 break;
155 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
156 case htons(ETH_P_IPV6):
157 ipv6_addr_copy(&ip.u.ip6, &ipv6_hdr(skb)->daddr);
158 break;
159 #endif
160 default:
161 return NULL;
162 }
163
164 return br_mdb_ip_get(mdb, &ip);
165 }
166
br_mdb_free(struct rcu_head * head)167 static void br_mdb_free(struct rcu_head *head)
168 {
169 struct net_bridge_mdb_htable *mdb =
170 container_of(head, struct net_bridge_mdb_htable, rcu);
171 struct net_bridge_mdb_htable *old = mdb->old;
172
173 mdb->old = NULL;
174 kfree(old->mhash);
175 kfree(old);
176 }
177
br_mdb_copy(struct net_bridge_mdb_htable * new,struct net_bridge_mdb_htable * old,int elasticity)178 static int br_mdb_copy(struct net_bridge_mdb_htable *new,
179 struct net_bridge_mdb_htable *old,
180 int elasticity)
181 {
182 struct net_bridge_mdb_entry *mp;
183 struct hlist_node *p;
184 int maxlen;
185 int len;
186 int i;
187
188 for (i = 0; i < old->max; i++)
189 hlist_for_each_entry(mp, p, &old->mhash[i], hlist[old->ver])
190 hlist_add_head(&mp->hlist[new->ver],
191 &new->mhash[br_ip_hash(new, &mp->addr)]);
192
193 if (!elasticity)
194 return 0;
195
196 maxlen = 0;
197 for (i = 0; i < new->max; i++) {
198 len = 0;
199 hlist_for_each_entry(mp, p, &new->mhash[i], hlist[new->ver])
200 len++;
201 if (len > maxlen)
202 maxlen = len;
203 }
204
205 return maxlen > elasticity ? -EINVAL : 0;
206 }
207
br_multicast_free_pg(struct rcu_head * head)208 static void br_multicast_free_pg(struct rcu_head *head)
209 {
210 struct net_bridge_port_group *p =
211 container_of(head, struct net_bridge_port_group, rcu);
212
213 kfree(p);
214 }
215
br_multicast_free_group(struct rcu_head * head)216 static void br_multicast_free_group(struct rcu_head *head)
217 {
218 struct net_bridge_mdb_entry *mp =
219 container_of(head, struct net_bridge_mdb_entry, rcu);
220
221 kfree(mp);
222 }
223
br_multicast_group_expired(unsigned long data)224 static void br_multicast_group_expired(unsigned long data)
225 {
226 struct net_bridge_mdb_entry *mp = (void *)data;
227 struct net_bridge *br = mp->br;
228 struct net_bridge_mdb_htable *mdb;
229
230 spin_lock(&br->multicast_lock);
231 if (!netif_running(br->dev) || timer_pending(&mp->timer))
232 goto out;
233
234 mp->mglist = false;
235
236 if (mp->ports)
237 goto out;
238
239 mdb = mlock_dereference(br->mdb, br);
240
241 hlist_del_rcu(&mp->hlist[mdb->ver]);
242 mdb->size--;
243
244 del_timer(&mp->query_timer);
245 call_rcu_bh(&mp->rcu, br_multicast_free_group);
246
247 out:
248 spin_unlock(&br->multicast_lock);
249 }
250
br_multicast_del_pg(struct net_bridge * br,struct net_bridge_port_group * pg)251 static void br_multicast_del_pg(struct net_bridge *br,
252 struct net_bridge_port_group *pg)
253 {
254 struct net_bridge_mdb_htable *mdb;
255 struct net_bridge_mdb_entry *mp;
256 struct net_bridge_port_group *p;
257 struct net_bridge_port_group __rcu **pp;
258
259 mdb = mlock_dereference(br->mdb, br);
260
261 mp = br_mdb_ip_get(mdb, &pg->addr);
262 if (WARN_ON(!mp))
263 return;
264
265 for (pp = &mp->ports;
266 (p = mlock_dereference(*pp, br)) != NULL;
267 pp = &p->next) {
268 if (p != pg)
269 continue;
270
271 rcu_assign_pointer(*pp, p->next);
272 hlist_del_init(&p->mglist);
273 del_timer(&p->timer);
274 del_timer(&p->query_timer);
275 call_rcu_bh(&p->rcu, br_multicast_free_pg);
276
277 if (!mp->ports && !mp->mglist &&
278 netif_running(br->dev))
279 mod_timer(&mp->timer, jiffies);
280
281 return;
282 }
283
284 WARN_ON(1);
285 }
286
br_multicast_port_group_expired(unsigned long data)287 static void br_multicast_port_group_expired(unsigned long data)
288 {
289 struct net_bridge_port_group *pg = (void *)data;
290 struct net_bridge *br = pg->port->br;
291
292 spin_lock(&br->multicast_lock);
293 if (!netif_running(br->dev) || timer_pending(&pg->timer) ||
294 hlist_unhashed(&pg->mglist))
295 goto out;
296
297 br_multicast_del_pg(br, pg);
298
299 out:
300 spin_unlock(&br->multicast_lock);
301 }
302
br_mdb_rehash(struct net_bridge_mdb_htable __rcu ** mdbp,int max,int elasticity)303 static int br_mdb_rehash(struct net_bridge_mdb_htable __rcu **mdbp, int max,
304 int elasticity)
305 {
306 struct net_bridge_mdb_htable *old = rcu_dereference_protected(*mdbp, 1);
307 struct net_bridge_mdb_htable *mdb;
308 int err;
309
310 mdb = kmalloc(sizeof(*mdb), GFP_ATOMIC);
311 if (!mdb)
312 return -ENOMEM;
313
314 mdb->max = max;
315 mdb->old = old;
316
317 mdb->mhash = kzalloc(max * sizeof(*mdb->mhash), GFP_ATOMIC);
318 if (!mdb->mhash) {
319 kfree(mdb);
320 return -ENOMEM;
321 }
322
323 mdb->size = old ? old->size : 0;
324 mdb->ver = old ? old->ver ^ 1 : 0;
325
326 if (!old || elasticity)
327 get_random_bytes(&mdb->secret, sizeof(mdb->secret));
328 else
329 mdb->secret = old->secret;
330
331 if (!old)
332 goto out;
333
334 err = br_mdb_copy(mdb, old, elasticity);
335 if (err) {
336 kfree(mdb->mhash);
337 kfree(mdb);
338 return err;
339 }
340
341 call_rcu_bh(&mdb->rcu, br_mdb_free);
342
343 out:
344 rcu_assign_pointer(*mdbp, mdb);
345
346 return 0;
347 }
348
br_ip4_multicast_alloc_query(struct net_bridge * br,__be32 group)349 static struct sk_buff *br_ip4_multicast_alloc_query(struct net_bridge *br,
350 __be32 group)
351 {
352 struct sk_buff *skb;
353 struct igmphdr *ih;
354 struct ethhdr *eth;
355 struct iphdr *iph;
356
357 skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*iph) +
358 sizeof(*ih) + 4);
359 if (!skb)
360 goto out;
361
362 skb->protocol = htons(ETH_P_IP);
363
364 skb_reset_mac_header(skb);
365 eth = eth_hdr(skb);
366
367 memcpy(eth->h_source, br->dev->dev_addr, 6);
368 eth->h_dest[0] = 1;
369 eth->h_dest[1] = 0;
370 eth->h_dest[2] = 0x5e;
371 eth->h_dest[3] = 0;
372 eth->h_dest[4] = 0;
373 eth->h_dest[5] = 1;
374 eth->h_proto = htons(ETH_P_IP);
375 skb_put(skb, sizeof(*eth));
376
377 skb_set_network_header(skb, skb->len);
378 iph = ip_hdr(skb);
379
380 iph->version = 4;
381 iph->ihl = 6;
382 iph->tos = 0xc0;
383 iph->tot_len = htons(sizeof(*iph) + sizeof(*ih) + 4);
384 iph->id = 0;
385 iph->frag_off = htons(IP_DF);
386 iph->ttl = 1;
387 iph->protocol = IPPROTO_IGMP;
388 iph->saddr = 0;
389 iph->daddr = htonl(INADDR_ALLHOSTS_GROUP);
390 ((u8 *)&iph[1])[0] = IPOPT_RA;
391 ((u8 *)&iph[1])[1] = 4;
392 ((u8 *)&iph[1])[2] = 0;
393 ((u8 *)&iph[1])[3] = 0;
394 ip_send_check(iph);
395 skb_put(skb, 24);
396
397 skb_set_transport_header(skb, skb->len);
398 ih = igmp_hdr(skb);
399 ih->type = IGMP_HOST_MEMBERSHIP_QUERY;
400 ih->code = (group ? br->multicast_last_member_interval :
401 br->multicast_query_response_interval) /
402 (HZ / IGMP_TIMER_SCALE);
403 ih->group = group;
404 ih->csum = 0;
405 ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
406 skb_put(skb, sizeof(*ih));
407
408 __skb_pull(skb, sizeof(*eth));
409
410 out:
411 return skb;
412 }
413
414 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
br_ip6_multicast_alloc_query(struct net_bridge * br,struct in6_addr * group)415 static struct sk_buff *br_ip6_multicast_alloc_query(struct net_bridge *br,
416 struct in6_addr *group)
417 {
418 struct sk_buff *skb;
419 struct ipv6hdr *ip6h;
420 struct mld_msg *mldq;
421 struct ethhdr *eth;
422 u8 *hopopt;
423 unsigned long interval;
424
425 skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*ip6h) +
426 8 + sizeof(*mldq));
427 if (!skb)
428 goto out;
429
430 skb->protocol = htons(ETH_P_IPV6);
431
432 /* Ethernet header */
433 skb_reset_mac_header(skb);
434 eth = eth_hdr(skb);
435
436 memcpy(eth->h_source, br->dev->dev_addr, 6);
437 eth->h_proto = htons(ETH_P_IPV6);
438 skb_put(skb, sizeof(*eth));
439
440 /* IPv6 header + HbH option */
441 skb_set_network_header(skb, skb->len);
442 ip6h = ipv6_hdr(skb);
443
444 *(__force __be32 *)ip6h = htonl(0x60000000);
445 ip6h->payload_len = htons(8 + sizeof(*mldq));
446 ip6h->nexthdr = IPPROTO_HOPOPTS;
447 ip6h->hop_limit = 1;
448 ipv6_addr_set(&ip6h->daddr, htonl(0xff020000), 0, 0, htonl(1));
449 ipv6_dev_get_saddr(dev_net(br->dev), br->dev, &ip6h->daddr, 0,
450 &ip6h->saddr);
451 ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest);
452
453 hopopt = (u8 *)(ip6h + 1);
454 hopopt[0] = IPPROTO_ICMPV6; /* next hdr */
455 hopopt[1] = 0; /* length of HbH */
456 hopopt[2] = IPV6_TLV_ROUTERALERT; /* Router Alert */
457 hopopt[3] = 2; /* Length of RA Option */
458 hopopt[4] = 0; /* Type = 0x0000 (MLD) */
459 hopopt[5] = 0;
460 hopopt[6] = IPV6_TLV_PAD0; /* Pad0 */
461 hopopt[7] = IPV6_TLV_PAD0; /* Pad0 */
462
463 skb_put(skb, sizeof(*ip6h) + 8);
464
465 /* ICMPv6 */
466 skb_set_transport_header(skb, skb->len);
467 mldq = (struct mld_msg *) icmp6_hdr(skb);
468
469 interval = ipv6_addr_any(group) ? br->multicast_last_member_interval :
470 br->multicast_query_response_interval;
471
472 mldq->mld_type = ICMPV6_MGM_QUERY;
473 mldq->mld_code = 0;
474 mldq->mld_cksum = 0;
475 mldq->mld_maxdelay = htons((u16)jiffies_to_msecs(interval));
476 mldq->mld_reserved = 0;
477 ipv6_addr_copy(&mldq->mld_mca, group);
478
479 /* checksum */
480 mldq->mld_cksum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
481 sizeof(*mldq), IPPROTO_ICMPV6,
482 csum_partial(mldq,
483 sizeof(*mldq), 0));
484 skb_put(skb, sizeof(*mldq));
485
486 __skb_pull(skb, sizeof(*eth));
487
488 out:
489 return skb;
490 }
491 #endif
492
br_multicast_alloc_query(struct net_bridge * br,struct br_ip * addr)493 static struct sk_buff *br_multicast_alloc_query(struct net_bridge *br,
494 struct br_ip *addr)
495 {
496 switch (addr->proto) {
497 case htons(ETH_P_IP):
498 return br_ip4_multicast_alloc_query(br, addr->u.ip4);
499 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
500 case htons(ETH_P_IPV6):
501 return br_ip6_multicast_alloc_query(br, &addr->u.ip6);
502 #endif
503 }
504 return NULL;
505 }
506
br_multicast_send_group_query(struct net_bridge_mdb_entry * mp)507 static void br_multicast_send_group_query(struct net_bridge_mdb_entry *mp)
508 {
509 struct net_bridge *br = mp->br;
510 struct sk_buff *skb;
511
512 skb = br_multicast_alloc_query(br, &mp->addr);
513 if (!skb)
514 goto timer;
515
516 netif_rx(skb);
517
518 timer:
519 if (++mp->queries_sent < br->multicast_last_member_count)
520 mod_timer(&mp->query_timer,
521 jiffies + br->multicast_last_member_interval);
522 }
523
br_multicast_group_query_expired(unsigned long data)524 static void br_multicast_group_query_expired(unsigned long data)
525 {
526 struct net_bridge_mdb_entry *mp = (void *)data;
527 struct net_bridge *br = mp->br;
528
529 spin_lock(&br->multicast_lock);
530 if (!netif_running(br->dev) || !mp->mglist ||
531 mp->queries_sent >= br->multicast_last_member_count)
532 goto out;
533
534 br_multicast_send_group_query(mp);
535
536 out:
537 spin_unlock(&br->multicast_lock);
538 }
539
br_multicast_send_port_group_query(struct net_bridge_port_group * pg)540 static void br_multicast_send_port_group_query(struct net_bridge_port_group *pg)
541 {
542 struct net_bridge_port *port = pg->port;
543 struct net_bridge *br = port->br;
544 struct sk_buff *skb;
545
546 skb = br_multicast_alloc_query(br, &pg->addr);
547 if (!skb)
548 goto timer;
549
550 br_deliver(port, skb);
551
552 timer:
553 if (++pg->queries_sent < br->multicast_last_member_count)
554 mod_timer(&pg->query_timer,
555 jiffies + br->multicast_last_member_interval);
556 }
557
br_multicast_port_group_query_expired(unsigned long data)558 static void br_multicast_port_group_query_expired(unsigned long data)
559 {
560 struct net_bridge_port_group *pg = (void *)data;
561 struct net_bridge_port *port = pg->port;
562 struct net_bridge *br = port->br;
563
564 spin_lock(&br->multicast_lock);
565 if (!netif_running(br->dev) || hlist_unhashed(&pg->mglist) ||
566 pg->queries_sent >= br->multicast_last_member_count)
567 goto out;
568
569 br_multicast_send_port_group_query(pg);
570
571 out:
572 spin_unlock(&br->multicast_lock);
573 }
574
br_multicast_get_group(struct net_bridge * br,struct net_bridge_port * port,struct br_ip * group,int hash)575 static struct net_bridge_mdb_entry *br_multicast_get_group(
576 struct net_bridge *br, struct net_bridge_port *port,
577 struct br_ip *group, int hash)
578 {
579 struct net_bridge_mdb_htable *mdb;
580 struct net_bridge_mdb_entry *mp;
581 struct hlist_node *p;
582 unsigned count = 0;
583 unsigned max;
584 int elasticity;
585 int err;
586
587 mdb = rcu_dereference_protected(br->mdb, 1);
588 hlist_for_each_entry(mp, p, &mdb->mhash[hash], hlist[mdb->ver]) {
589 count++;
590 if (unlikely(br_ip_equal(group, &mp->addr)))
591 return mp;
592 }
593
594 elasticity = 0;
595 max = mdb->max;
596
597 if (unlikely(count > br->hash_elasticity && count)) {
598 if (net_ratelimit())
599 br_info(br, "Multicast hash table "
600 "chain limit reached: %s\n",
601 port ? port->dev->name : br->dev->name);
602
603 elasticity = br->hash_elasticity;
604 }
605
606 if (mdb->size >= max) {
607 max *= 2;
608 if (unlikely(max >= br->hash_max)) {
609 br_warn(br, "Multicast hash table maximum "
610 "reached, disabling snooping: %s, %d\n",
611 port ? port->dev->name : br->dev->name, max);
612 err = -E2BIG;
613 disable:
614 br->multicast_disabled = 1;
615 goto err;
616 }
617 }
618
619 if (max > mdb->max || elasticity) {
620 if (mdb->old) {
621 if (net_ratelimit())
622 br_info(br, "Multicast hash table "
623 "on fire: %s\n",
624 port ? port->dev->name : br->dev->name);
625 err = -EEXIST;
626 goto err;
627 }
628
629 err = br_mdb_rehash(&br->mdb, max, elasticity);
630 if (err) {
631 br_warn(br, "Cannot rehash multicast "
632 "hash table, disabling snooping: %s, %d, %d\n",
633 port ? port->dev->name : br->dev->name,
634 mdb->size, err);
635 goto disable;
636 }
637
638 err = -EAGAIN;
639 goto err;
640 }
641
642 return NULL;
643
644 err:
645 mp = ERR_PTR(err);
646 return mp;
647 }
648
br_multicast_new_group(struct net_bridge * br,struct net_bridge_port * port,struct br_ip * group)649 static struct net_bridge_mdb_entry *br_multicast_new_group(
650 struct net_bridge *br, struct net_bridge_port *port,
651 struct br_ip *group)
652 {
653 struct net_bridge_mdb_htable *mdb;
654 struct net_bridge_mdb_entry *mp;
655 int hash;
656 int err;
657
658 mdb = rcu_dereference_protected(br->mdb, 1);
659 if (!mdb) {
660 err = br_mdb_rehash(&br->mdb, BR_HASH_SIZE, 0);
661 if (err)
662 return ERR_PTR(err);
663 goto rehash;
664 }
665
666 hash = br_ip_hash(mdb, group);
667 mp = br_multicast_get_group(br, port, group, hash);
668 switch (PTR_ERR(mp)) {
669 case 0:
670 break;
671
672 case -EAGAIN:
673 rehash:
674 mdb = rcu_dereference_protected(br->mdb, 1);
675 hash = br_ip_hash(mdb, group);
676 break;
677
678 default:
679 goto out;
680 }
681
682 mp = kzalloc(sizeof(*mp), GFP_ATOMIC);
683 if (unlikely(!mp))
684 return ERR_PTR(-ENOMEM);
685
686 mp->br = br;
687 mp->addr = *group;
688 setup_timer(&mp->timer, br_multicast_group_expired,
689 (unsigned long)mp);
690 setup_timer(&mp->query_timer, br_multicast_group_query_expired,
691 (unsigned long)mp);
692
693 hlist_add_head_rcu(&mp->hlist[mdb->ver], &mdb->mhash[hash]);
694 mdb->size++;
695
696 out:
697 return mp;
698 }
699
br_multicast_add_group(struct net_bridge * br,struct net_bridge_port * port,struct br_ip * group)700 static int br_multicast_add_group(struct net_bridge *br,
701 struct net_bridge_port *port,
702 struct br_ip *group)
703 {
704 struct net_bridge_mdb_entry *mp;
705 struct net_bridge_port_group *p;
706 struct net_bridge_port_group __rcu **pp;
707 unsigned long now = jiffies;
708 int err;
709
710 spin_lock(&br->multicast_lock);
711 if (!netif_running(br->dev) ||
712 (port && port->state == BR_STATE_DISABLED))
713 goto out;
714
715 mp = br_multicast_new_group(br, port, group);
716 err = PTR_ERR(mp);
717 if (IS_ERR(mp))
718 goto err;
719
720 if (!port) {
721 mp->mglist = true;
722 mod_timer(&mp->timer, now + br->multicast_membership_interval);
723 goto out;
724 }
725
726 for (pp = &mp->ports;
727 (p = mlock_dereference(*pp, br)) != NULL;
728 pp = &p->next) {
729 if (p->port == port)
730 goto found;
731 if ((unsigned long)p->port < (unsigned long)port)
732 break;
733 }
734
735 p = kzalloc(sizeof(*p), GFP_ATOMIC);
736 err = -ENOMEM;
737 if (unlikely(!p))
738 goto err;
739
740 p->addr = *group;
741 p->port = port;
742 p->next = *pp;
743 hlist_add_head(&p->mglist, &port->mglist);
744 setup_timer(&p->timer, br_multicast_port_group_expired,
745 (unsigned long)p);
746 setup_timer(&p->query_timer, br_multicast_port_group_query_expired,
747 (unsigned long)p);
748
749 rcu_assign_pointer(*pp, p);
750
751 found:
752 mod_timer(&p->timer, now + br->multicast_membership_interval);
753 out:
754 err = 0;
755
756 err:
757 spin_unlock(&br->multicast_lock);
758 return err;
759 }
760
br_ip4_multicast_add_group(struct net_bridge * br,struct net_bridge_port * port,__be32 group)761 static int br_ip4_multicast_add_group(struct net_bridge *br,
762 struct net_bridge_port *port,
763 __be32 group)
764 {
765 struct br_ip br_group;
766
767 if (ipv4_is_local_multicast(group))
768 return 0;
769
770 br_group.u.ip4 = group;
771 br_group.proto = htons(ETH_P_IP);
772
773 return br_multicast_add_group(br, port, &br_group);
774 }
775
776 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
br_ip6_multicast_add_group(struct net_bridge * br,struct net_bridge_port * port,const struct in6_addr * group)777 static int br_ip6_multicast_add_group(struct net_bridge *br,
778 struct net_bridge_port *port,
779 const struct in6_addr *group)
780 {
781 struct br_ip br_group;
782
783 if (!ipv6_is_transient_multicast(group))
784 return 0;
785
786 ipv6_addr_copy(&br_group.u.ip6, group);
787 br_group.proto = htons(ETH_P_IPV6);
788
789 return br_multicast_add_group(br, port, &br_group);
790 }
791 #endif
792
br_multicast_router_expired(unsigned long data)793 static void br_multicast_router_expired(unsigned long data)
794 {
795 struct net_bridge_port *port = (void *)data;
796 struct net_bridge *br = port->br;
797
798 spin_lock(&br->multicast_lock);
799 if (port->multicast_router != 1 ||
800 timer_pending(&port->multicast_router_timer) ||
801 hlist_unhashed(&port->rlist))
802 goto out;
803
804 hlist_del_init_rcu(&port->rlist);
805
806 out:
807 spin_unlock(&br->multicast_lock);
808 }
809
br_multicast_local_router_expired(unsigned long data)810 static void br_multicast_local_router_expired(unsigned long data)
811 {
812 }
813
__br_multicast_send_query(struct net_bridge * br,struct net_bridge_port * port,struct br_ip * ip)814 static void __br_multicast_send_query(struct net_bridge *br,
815 struct net_bridge_port *port,
816 struct br_ip *ip)
817 {
818 struct sk_buff *skb;
819
820 skb = br_multicast_alloc_query(br, ip);
821 if (!skb)
822 return;
823
824 if (port) {
825 __skb_push(skb, sizeof(struct ethhdr));
826 skb->dev = port->dev;
827 NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
828 dev_queue_xmit);
829 } else
830 netif_rx(skb);
831 }
832
br_multicast_send_query(struct net_bridge * br,struct net_bridge_port * port,u32 sent)833 static void br_multicast_send_query(struct net_bridge *br,
834 struct net_bridge_port *port, u32 sent)
835 {
836 unsigned long time;
837 struct br_ip br_group;
838
839 if (!netif_running(br->dev) || br->multicast_disabled ||
840 timer_pending(&br->multicast_querier_timer))
841 return;
842
843 memset(&br_group.u, 0, sizeof(br_group.u));
844
845 br_group.proto = htons(ETH_P_IP);
846 __br_multicast_send_query(br, port, &br_group);
847
848 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
849 br_group.proto = htons(ETH_P_IPV6);
850 __br_multicast_send_query(br, port, &br_group);
851 #endif
852
853 time = jiffies;
854 time += sent < br->multicast_startup_query_count ?
855 br->multicast_startup_query_interval :
856 br->multicast_query_interval;
857 mod_timer(port ? &port->multicast_query_timer :
858 &br->multicast_query_timer, time);
859 }
860
br_multicast_port_query_expired(unsigned long data)861 static void br_multicast_port_query_expired(unsigned long data)
862 {
863 struct net_bridge_port *port = (void *)data;
864 struct net_bridge *br = port->br;
865
866 spin_lock(&br->multicast_lock);
867 if (port->state == BR_STATE_DISABLED ||
868 port->state == BR_STATE_BLOCKING)
869 goto out;
870
871 if (port->multicast_startup_queries_sent <
872 br->multicast_startup_query_count)
873 port->multicast_startup_queries_sent++;
874
875 br_multicast_send_query(port->br, port,
876 port->multicast_startup_queries_sent);
877
878 out:
879 spin_unlock(&br->multicast_lock);
880 }
881
br_multicast_add_port(struct net_bridge_port * port)882 void br_multicast_add_port(struct net_bridge_port *port)
883 {
884 port->multicast_router = 1;
885
886 setup_timer(&port->multicast_router_timer, br_multicast_router_expired,
887 (unsigned long)port);
888 setup_timer(&port->multicast_query_timer,
889 br_multicast_port_query_expired, (unsigned long)port);
890 }
891
br_multicast_del_port(struct net_bridge_port * port)892 void br_multicast_del_port(struct net_bridge_port *port)
893 {
894 del_timer_sync(&port->multicast_router_timer);
895 }
896
__br_multicast_enable_port(struct net_bridge_port * port)897 static void __br_multicast_enable_port(struct net_bridge_port *port)
898 {
899 port->multicast_startup_queries_sent = 0;
900
901 if (try_to_del_timer_sync(&port->multicast_query_timer) >= 0 ||
902 del_timer(&port->multicast_query_timer))
903 mod_timer(&port->multicast_query_timer, jiffies);
904 }
905
br_multicast_enable_port(struct net_bridge_port * port)906 void br_multicast_enable_port(struct net_bridge_port *port)
907 {
908 struct net_bridge *br = port->br;
909
910 spin_lock(&br->multicast_lock);
911 if (br->multicast_disabled || !netif_running(br->dev))
912 goto out;
913
914 __br_multicast_enable_port(port);
915
916 out:
917 spin_unlock(&br->multicast_lock);
918 }
919
br_multicast_disable_port(struct net_bridge_port * port)920 void br_multicast_disable_port(struct net_bridge_port *port)
921 {
922 struct net_bridge *br = port->br;
923 struct net_bridge_port_group *pg;
924 struct hlist_node *p, *n;
925
926 spin_lock(&br->multicast_lock);
927 hlist_for_each_entry_safe(pg, p, n, &port->mglist, mglist)
928 br_multicast_del_pg(br, pg);
929
930 if (!hlist_unhashed(&port->rlist))
931 hlist_del_init_rcu(&port->rlist);
932 del_timer(&port->multicast_router_timer);
933 del_timer(&port->multicast_query_timer);
934 spin_unlock(&br->multicast_lock);
935 }
936
br_ip4_multicast_igmp3_report(struct net_bridge * br,struct net_bridge_port * port,struct sk_buff * skb)937 static int br_ip4_multicast_igmp3_report(struct net_bridge *br,
938 struct net_bridge_port *port,
939 struct sk_buff *skb)
940 {
941 struct igmpv3_report *ih;
942 struct igmpv3_grec *grec;
943 int i;
944 int len;
945 int num;
946 int type;
947 int err = 0;
948 __be32 group;
949
950 if (!pskb_may_pull(skb, sizeof(*ih)))
951 return -EINVAL;
952
953 ih = igmpv3_report_hdr(skb);
954 num = ntohs(ih->ngrec);
955 len = sizeof(*ih);
956
957 for (i = 0; i < num; i++) {
958 len += sizeof(*grec);
959 if (!pskb_may_pull(skb, len))
960 return -EINVAL;
961
962 grec = (void *)(skb->data + len - sizeof(*grec));
963 group = grec->grec_mca;
964 type = grec->grec_type;
965
966 len += ntohs(grec->grec_nsrcs) * 4;
967 if (!pskb_may_pull(skb, len))
968 return -EINVAL;
969
970 /* We treat this as an IGMPv2 report for now. */
971 switch (type) {
972 case IGMPV3_MODE_IS_INCLUDE:
973 case IGMPV3_MODE_IS_EXCLUDE:
974 case IGMPV3_CHANGE_TO_INCLUDE:
975 case IGMPV3_CHANGE_TO_EXCLUDE:
976 case IGMPV3_ALLOW_NEW_SOURCES:
977 case IGMPV3_BLOCK_OLD_SOURCES:
978 break;
979
980 default:
981 continue;
982 }
983
984 err = br_ip4_multicast_add_group(br, port, group);
985 if (err)
986 break;
987 }
988
989 return err;
990 }
991
992 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
br_ip6_multicast_mld2_report(struct net_bridge * br,struct net_bridge_port * port,struct sk_buff * skb)993 static int br_ip6_multicast_mld2_report(struct net_bridge *br,
994 struct net_bridge_port *port,
995 struct sk_buff *skb)
996 {
997 struct icmp6hdr *icmp6h;
998 struct mld2_grec *grec;
999 int i;
1000 int len;
1001 int num;
1002 int err = 0;
1003
1004 if (!pskb_may_pull(skb, sizeof(*icmp6h)))
1005 return -EINVAL;
1006
1007 icmp6h = icmp6_hdr(skb);
1008 num = ntohs(icmp6h->icmp6_dataun.un_data16[1]);
1009 len = sizeof(*icmp6h);
1010
1011 for (i = 0; i < num; i++) {
1012 __be16 *nsrcs, _nsrcs;
1013
1014 nsrcs = skb_header_pointer(skb,
1015 len + offsetof(struct mld2_grec,
1016 grec_nsrcs),
1017 sizeof(_nsrcs), &_nsrcs);
1018 if (!nsrcs)
1019 return -EINVAL;
1020
1021 if (!pskb_may_pull(skb,
1022 len + sizeof(*grec) +
1023 sizeof(struct in6_addr) * ntohs(*nsrcs)))
1024 return -EINVAL;
1025
1026 grec = (struct mld2_grec *)(skb->data + len);
1027 len += sizeof(*grec) +
1028 sizeof(struct in6_addr) * ntohs(*nsrcs);
1029
1030 /* We treat these as MLDv1 reports for now. */
1031 switch (grec->grec_type) {
1032 case MLD2_MODE_IS_INCLUDE:
1033 case MLD2_MODE_IS_EXCLUDE:
1034 case MLD2_CHANGE_TO_INCLUDE:
1035 case MLD2_CHANGE_TO_EXCLUDE:
1036 case MLD2_ALLOW_NEW_SOURCES:
1037 case MLD2_BLOCK_OLD_SOURCES:
1038 break;
1039
1040 default:
1041 continue;
1042 }
1043
1044 err = br_ip6_multicast_add_group(br, port, &grec->grec_mca);
1045 if (!err)
1046 break;
1047 }
1048
1049 return err;
1050 }
1051 #endif
1052
1053 /*
1054 * Add port to rotuer_list
1055 * list is maintained ordered by pointer value
1056 * and locked by br->multicast_lock and RCU
1057 */
br_multicast_add_router(struct net_bridge * br,struct net_bridge_port * port)1058 static void br_multicast_add_router(struct net_bridge *br,
1059 struct net_bridge_port *port)
1060 {
1061 struct net_bridge_port *p;
1062 struct hlist_node *n, *slot = NULL;
1063
1064 hlist_for_each_entry(p, n, &br->router_list, rlist) {
1065 if ((unsigned long) port >= (unsigned long) p)
1066 break;
1067 slot = n;
1068 }
1069
1070 if (slot)
1071 hlist_add_after_rcu(slot, &port->rlist);
1072 else
1073 hlist_add_head_rcu(&port->rlist, &br->router_list);
1074 }
1075
br_multicast_mark_router(struct net_bridge * br,struct net_bridge_port * port)1076 static void br_multicast_mark_router(struct net_bridge *br,
1077 struct net_bridge_port *port)
1078 {
1079 unsigned long now = jiffies;
1080
1081 if (!port) {
1082 if (br->multicast_router == 1)
1083 mod_timer(&br->multicast_router_timer,
1084 now + br->multicast_querier_interval);
1085 return;
1086 }
1087
1088 if (port->multicast_router != 1)
1089 return;
1090
1091 if (!hlist_unhashed(&port->rlist))
1092 goto timer;
1093
1094 br_multicast_add_router(br, port);
1095
1096 timer:
1097 mod_timer(&port->multicast_router_timer,
1098 now + br->multicast_querier_interval);
1099 }
1100
br_multicast_query_received(struct net_bridge * br,struct net_bridge_port * port,int saddr)1101 static void br_multicast_query_received(struct net_bridge *br,
1102 struct net_bridge_port *port,
1103 int saddr)
1104 {
1105 if (saddr)
1106 mod_timer(&br->multicast_querier_timer,
1107 jiffies + br->multicast_querier_interval);
1108 else if (timer_pending(&br->multicast_querier_timer))
1109 return;
1110
1111 br_multicast_mark_router(br, port);
1112 }
1113
br_ip4_multicast_query(struct net_bridge * br,struct net_bridge_port * port,struct sk_buff * skb)1114 static int br_ip4_multicast_query(struct net_bridge *br,
1115 struct net_bridge_port *port,
1116 struct sk_buff *skb)
1117 {
1118 struct iphdr *iph = ip_hdr(skb);
1119 struct igmphdr *ih = igmp_hdr(skb);
1120 struct net_bridge_mdb_entry *mp;
1121 struct igmpv3_query *ih3;
1122 struct net_bridge_port_group *p;
1123 struct net_bridge_port_group __rcu **pp;
1124 unsigned long max_delay;
1125 unsigned long now = jiffies;
1126 __be32 group;
1127 int err = 0;
1128
1129 spin_lock(&br->multicast_lock);
1130 if (!netif_running(br->dev) ||
1131 (port && port->state == BR_STATE_DISABLED))
1132 goto out;
1133
1134 br_multicast_query_received(br, port, !!iph->saddr);
1135
1136 group = ih->group;
1137
1138 if (skb->len == sizeof(*ih)) {
1139 max_delay = ih->code * (HZ / IGMP_TIMER_SCALE);
1140
1141 if (!max_delay) {
1142 max_delay = 10 * HZ;
1143 group = 0;
1144 }
1145 } else {
1146 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query))) {
1147 err = -EINVAL;
1148 goto out;
1149 }
1150
1151 ih3 = igmpv3_query_hdr(skb);
1152 if (ih3->nsrcs)
1153 goto out;
1154
1155 max_delay = ih3->code ?
1156 IGMPV3_MRC(ih3->code) * (HZ / IGMP_TIMER_SCALE) : 1;
1157 }
1158
1159 if (!group)
1160 goto out;
1161
1162 mp = br_mdb_ip4_get(mlock_dereference(br->mdb, br), group);
1163 if (!mp)
1164 goto out;
1165
1166 max_delay *= br->multicast_last_member_count;
1167
1168 if (mp->mglist &&
1169 (timer_pending(&mp->timer) ?
1170 time_after(mp->timer.expires, now + max_delay) :
1171 try_to_del_timer_sync(&mp->timer) >= 0))
1172 mod_timer(&mp->timer, now + max_delay);
1173
1174 for (pp = &mp->ports;
1175 (p = mlock_dereference(*pp, br)) != NULL;
1176 pp = &p->next) {
1177 if (timer_pending(&p->timer) ?
1178 time_after(p->timer.expires, now + max_delay) :
1179 try_to_del_timer_sync(&p->timer) >= 0)
1180 mod_timer(&p->timer, now + max_delay);
1181 }
1182
1183 out:
1184 spin_unlock(&br->multicast_lock);
1185 return err;
1186 }
1187
1188 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
br_ip6_multicast_query(struct net_bridge * br,struct net_bridge_port * port,struct sk_buff * skb)1189 static int br_ip6_multicast_query(struct net_bridge *br,
1190 struct net_bridge_port *port,
1191 struct sk_buff *skb)
1192 {
1193 struct ipv6hdr *ip6h = ipv6_hdr(skb);
1194 struct mld_msg *mld = (struct mld_msg *) icmp6_hdr(skb);
1195 struct net_bridge_mdb_entry *mp;
1196 struct mld2_query *mld2q;
1197 struct net_bridge_port_group *p;
1198 struct net_bridge_port_group __rcu **pp;
1199 unsigned long max_delay;
1200 unsigned long now = jiffies;
1201 struct in6_addr *group = NULL;
1202 int err = 0;
1203
1204 spin_lock(&br->multicast_lock);
1205 if (!netif_running(br->dev) ||
1206 (port && port->state == BR_STATE_DISABLED))
1207 goto out;
1208
1209 br_multicast_query_received(br, port, !ipv6_addr_any(&ip6h->saddr));
1210
1211 if (skb->len == sizeof(*mld)) {
1212 if (!pskb_may_pull(skb, sizeof(*mld))) {
1213 err = -EINVAL;
1214 goto out;
1215 }
1216 mld = (struct mld_msg *) icmp6_hdr(skb);
1217 max_delay = msecs_to_jiffies(htons(mld->mld_maxdelay));
1218 if (max_delay)
1219 group = &mld->mld_mca;
1220 } else if (skb->len >= sizeof(*mld2q)) {
1221 if (!pskb_may_pull(skb, sizeof(*mld2q))) {
1222 err = -EINVAL;
1223 goto out;
1224 }
1225 mld2q = (struct mld2_query *)icmp6_hdr(skb);
1226 if (!mld2q->mld2q_nsrcs)
1227 group = &mld2q->mld2q_mca;
1228 max_delay = mld2q->mld2q_mrc ? MLDV2_MRC(mld2q->mld2q_mrc) : 1;
1229 }
1230
1231 if (!group)
1232 goto out;
1233
1234 mp = br_mdb_ip6_get(mlock_dereference(br->mdb, br), group);
1235 if (!mp)
1236 goto out;
1237
1238 max_delay *= br->multicast_last_member_count;
1239 if (mp->mglist &&
1240 (timer_pending(&mp->timer) ?
1241 time_after(mp->timer.expires, now + max_delay) :
1242 try_to_del_timer_sync(&mp->timer) >= 0))
1243 mod_timer(&mp->timer, now + max_delay);
1244
1245 for (pp = &mp->ports;
1246 (p = mlock_dereference(*pp, br)) != NULL;
1247 pp = &p->next) {
1248 if (timer_pending(&p->timer) ?
1249 time_after(p->timer.expires, now + max_delay) :
1250 try_to_del_timer_sync(&p->timer) >= 0)
1251 mod_timer(&p->timer, now + max_delay);
1252 }
1253
1254 out:
1255 spin_unlock(&br->multicast_lock);
1256 return err;
1257 }
1258 #endif
1259
br_multicast_leave_group(struct net_bridge * br,struct net_bridge_port * port,struct br_ip * group)1260 static void br_multicast_leave_group(struct net_bridge *br,
1261 struct net_bridge_port *port,
1262 struct br_ip *group)
1263 {
1264 struct net_bridge_mdb_htable *mdb;
1265 struct net_bridge_mdb_entry *mp;
1266 struct net_bridge_port_group *p;
1267 unsigned long now;
1268 unsigned long time;
1269
1270 spin_lock(&br->multicast_lock);
1271 if (!netif_running(br->dev) ||
1272 (port && port->state == BR_STATE_DISABLED) ||
1273 timer_pending(&br->multicast_querier_timer))
1274 goto out;
1275
1276 mdb = mlock_dereference(br->mdb, br);
1277 mp = br_mdb_ip_get(mdb, group);
1278 if (!mp)
1279 goto out;
1280
1281 now = jiffies;
1282 time = now + br->multicast_last_member_count *
1283 br->multicast_last_member_interval;
1284
1285 if (!port) {
1286 if (mp->mglist &&
1287 (timer_pending(&mp->timer) ?
1288 time_after(mp->timer.expires, time) :
1289 try_to_del_timer_sync(&mp->timer) >= 0)) {
1290 mod_timer(&mp->timer, time);
1291
1292 mp->queries_sent = 0;
1293 mod_timer(&mp->query_timer, now);
1294 }
1295
1296 goto out;
1297 }
1298
1299 for (p = mlock_dereference(mp->ports, br);
1300 p != NULL;
1301 p = mlock_dereference(p->next, br)) {
1302 if (p->port != port)
1303 continue;
1304
1305 if (!hlist_unhashed(&p->mglist) &&
1306 (timer_pending(&p->timer) ?
1307 time_after(p->timer.expires, time) :
1308 try_to_del_timer_sync(&p->timer) >= 0)) {
1309 mod_timer(&p->timer, time);
1310
1311 p->queries_sent = 0;
1312 mod_timer(&p->query_timer, now);
1313 }
1314
1315 break;
1316 }
1317
1318 out:
1319 spin_unlock(&br->multicast_lock);
1320 }
1321
br_ip4_multicast_leave_group(struct net_bridge * br,struct net_bridge_port * port,__be32 group)1322 static void br_ip4_multicast_leave_group(struct net_bridge *br,
1323 struct net_bridge_port *port,
1324 __be32 group)
1325 {
1326 struct br_ip br_group;
1327
1328 if (ipv4_is_local_multicast(group))
1329 return;
1330
1331 br_group.u.ip4 = group;
1332 br_group.proto = htons(ETH_P_IP);
1333
1334 br_multicast_leave_group(br, port, &br_group);
1335 }
1336
1337 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
br_ip6_multicast_leave_group(struct net_bridge * br,struct net_bridge_port * port,const struct in6_addr * group)1338 static void br_ip6_multicast_leave_group(struct net_bridge *br,
1339 struct net_bridge_port *port,
1340 const struct in6_addr *group)
1341 {
1342 struct br_ip br_group;
1343
1344 if (!ipv6_is_transient_multicast(group))
1345 return;
1346
1347 ipv6_addr_copy(&br_group.u.ip6, group);
1348 br_group.proto = htons(ETH_P_IPV6);
1349
1350 br_multicast_leave_group(br, port, &br_group);
1351 }
1352 #endif
1353
br_multicast_ipv4_rcv(struct net_bridge * br,struct net_bridge_port * port,struct sk_buff * skb)1354 static int br_multicast_ipv4_rcv(struct net_bridge *br,
1355 struct net_bridge_port *port,
1356 struct sk_buff *skb)
1357 {
1358 struct sk_buff *skb2 = skb;
1359 struct iphdr *iph;
1360 struct igmphdr *ih;
1361 unsigned len;
1362 unsigned offset;
1363 int err;
1364
1365 /* We treat OOM as packet loss for now. */
1366 if (!pskb_may_pull(skb, sizeof(*iph)))
1367 return -EINVAL;
1368
1369 iph = ip_hdr(skb);
1370
1371 if (iph->ihl < 5 || iph->version != 4)
1372 return -EINVAL;
1373
1374 if (!pskb_may_pull(skb, ip_hdrlen(skb)))
1375 return -EINVAL;
1376
1377 iph = ip_hdr(skb);
1378
1379 if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1380 return -EINVAL;
1381
1382 if (iph->protocol != IPPROTO_IGMP)
1383 return 0;
1384
1385 len = ntohs(iph->tot_len);
1386 if (skb->len < len || len < ip_hdrlen(skb))
1387 return -EINVAL;
1388
1389 if (skb->len > len) {
1390 skb2 = skb_clone(skb, GFP_ATOMIC);
1391 if (!skb2)
1392 return -ENOMEM;
1393
1394 err = pskb_trim_rcsum(skb2, len);
1395 if (err)
1396 goto err_out;
1397 }
1398
1399 len -= ip_hdrlen(skb2);
1400 offset = skb_network_offset(skb2) + ip_hdrlen(skb2);
1401 __skb_pull(skb2, offset);
1402 skb_reset_transport_header(skb2);
1403
1404 err = -EINVAL;
1405 if (!pskb_may_pull(skb2, sizeof(*ih)))
1406 goto out;
1407
1408 switch (skb2->ip_summed) {
1409 case CHECKSUM_COMPLETE:
1410 if (!csum_fold(skb2->csum))
1411 break;
1412 /* fall through */
1413 case CHECKSUM_NONE:
1414 skb2->csum = 0;
1415 if (skb_checksum_complete(skb2))
1416 goto out;
1417 }
1418
1419 err = 0;
1420
1421 BR_INPUT_SKB_CB(skb)->igmp = 1;
1422 ih = igmp_hdr(skb2);
1423
1424 switch (ih->type) {
1425 case IGMP_HOST_MEMBERSHIP_REPORT:
1426 case IGMPV2_HOST_MEMBERSHIP_REPORT:
1427 BR_INPUT_SKB_CB(skb2)->mrouters_only = 1;
1428 err = br_ip4_multicast_add_group(br, port, ih->group);
1429 break;
1430 case IGMPV3_HOST_MEMBERSHIP_REPORT:
1431 err = br_ip4_multicast_igmp3_report(br, port, skb2);
1432 break;
1433 case IGMP_HOST_MEMBERSHIP_QUERY:
1434 err = br_ip4_multicast_query(br, port, skb2);
1435 break;
1436 case IGMP_HOST_LEAVE_MESSAGE:
1437 br_ip4_multicast_leave_group(br, port, ih->group);
1438 break;
1439 }
1440
1441 out:
1442 __skb_push(skb2, offset);
1443 err_out:
1444 if (skb2 != skb)
1445 kfree_skb(skb2);
1446 return err;
1447 }
1448
1449 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
br_multicast_ipv6_rcv(struct net_bridge * br,struct net_bridge_port * port,struct sk_buff * skb)1450 static int br_multicast_ipv6_rcv(struct net_bridge *br,
1451 struct net_bridge_port *port,
1452 struct sk_buff *skb)
1453 {
1454 struct sk_buff *skb2;
1455 struct ipv6hdr *ip6h;
1456 struct icmp6hdr *icmp6h;
1457 u8 nexthdr;
1458 unsigned len;
1459 int offset;
1460 int err;
1461
1462 if (!pskb_may_pull(skb, sizeof(*ip6h)))
1463 return -EINVAL;
1464
1465 ip6h = ipv6_hdr(skb);
1466
1467 /*
1468 * We're interested in MLD messages only.
1469 * - Version is 6
1470 * - MLD has always Router Alert hop-by-hop option
1471 * - But we do not support jumbrograms.
1472 */
1473 if (ip6h->version != 6 ||
1474 ip6h->nexthdr != IPPROTO_HOPOPTS ||
1475 ip6h->payload_len == 0)
1476 return 0;
1477
1478 len = ntohs(ip6h->payload_len) + sizeof(*ip6h);
1479 if (skb->len < len)
1480 return -EINVAL;
1481
1482 nexthdr = ip6h->nexthdr;
1483 offset = ipv6_skip_exthdr(skb, sizeof(*ip6h), &nexthdr);
1484
1485 if (offset < 0 || nexthdr != IPPROTO_ICMPV6)
1486 return 0;
1487
1488 /* Okay, we found ICMPv6 header */
1489 skb2 = skb_clone(skb, GFP_ATOMIC);
1490 if (!skb2)
1491 return -ENOMEM;
1492
1493 err = -EINVAL;
1494 if (!pskb_may_pull(skb2, offset + sizeof(struct icmp6hdr)))
1495 goto out;
1496
1497 len -= offset - skb_network_offset(skb2);
1498
1499 __skb_pull(skb2, offset);
1500 skb_reset_transport_header(skb2);
1501
1502 icmp6h = icmp6_hdr(skb2);
1503
1504 switch (icmp6h->icmp6_type) {
1505 case ICMPV6_MGM_QUERY:
1506 case ICMPV6_MGM_REPORT:
1507 case ICMPV6_MGM_REDUCTION:
1508 case ICMPV6_MLD2_REPORT:
1509 break;
1510 default:
1511 err = 0;
1512 goto out;
1513 }
1514
1515 /* Okay, we found MLD message. Check further. */
1516 if (skb2->len > len) {
1517 err = pskb_trim_rcsum(skb2, len);
1518 if (err)
1519 goto out;
1520 }
1521
1522 switch (skb2->ip_summed) {
1523 case CHECKSUM_COMPLETE:
1524 if (!csum_fold(skb2->csum))
1525 break;
1526 /*FALLTHROUGH*/
1527 case CHECKSUM_NONE:
1528 skb2->csum = 0;
1529 if (skb_checksum_complete(skb2))
1530 goto out;
1531 }
1532
1533 err = 0;
1534
1535 BR_INPUT_SKB_CB(skb)->igmp = 1;
1536
1537 switch (icmp6h->icmp6_type) {
1538 case ICMPV6_MGM_REPORT:
1539 {
1540 struct mld_msg *mld;
1541 if (!pskb_may_pull(skb2, sizeof(*mld))) {
1542 err = -EINVAL;
1543 goto out;
1544 }
1545 mld = (struct mld_msg *)skb_transport_header(skb2);
1546 BR_INPUT_SKB_CB(skb2)->mrouters_only = 1;
1547 err = br_ip6_multicast_add_group(br, port, &mld->mld_mca);
1548 break;
1549 }
1550 case ICMPV6_MLD2_REPORT:
1551 err = br_ip6_multicast_mld2_report(br, port, skb2);
1552 break;
1553 case ICMPV6_MGM_QUERY:
1554 err = br_ip6_multicast_query(br, port, skb2);
1555 break;
1556 case ICMPV6_MGM_REDUCTION:
1557 {
1558 struct mld_msg *mld;
1559 if (!pskb_may_pull(skb2, sizeof(*mld))) {
1560 err = -EINVAL;
1561 goto out;
1562 }
1563 mld = (struct mld_msg *)skb_transport_header(skb2);
1564 br_ip6_multicast_leave_group(br, port, &mld->mld_mca);
1565 }
1566 }
1567
1568 out:
1569 kfree_skb(skb2);
1570 return err;
1571 }
1572 #endif
1573
br_multicast_rcv(struct net_bridge * br,struct net_bridge_port * port,struct sk_buff * skb)1574 int br_multicast_rcv(struct net_bridge *br, struct net_bridge_port *port,
1575 struct sk_buff *skb)
1576 {
1577 BR_INPUT_SKB_CB(skb)->igmp = 0;
1578 BR_INPUT_SKB_CB(skb)->mrouters_only = 0;
1579
1580 if (br->multicast_disabled)
1581 return 0;
1582
1583 switch (skb->protocol) {
1584 case htons(ETH_P_IP):
1585 return br_multicast_ipv4_rcv(br, port, skb);
1586 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1587 case htons(ETH_P_IPV6):
1588 return br_multicast_ipv6_rcv(br, port, skb);
1589 #endif
1590 }
1591
1592 return 0;
1593 }
1594
br_multicast_query_expired(unsigned long data)1595 static void br_multicast_query_expired(unsigned long data)
1596 {
1597 struct net_bridge *br = (void *)data;
1598
1599 spin_lock(&br->multicast_lock);
1600 if (br->multicast_startup_queries_sent <
1601 br->multicast_startup_query_count)
1602 br->multicast_startup_queries_sent++;
1603
1604 br_multicast_send_query(br, NULL, br->multicast_startup_queries_sent);
1605
1606 spin_unlock(&br->multicast_lock);
1607 }
1608
br_multicast_init(struct net_bridge * br)1609 void br_multicast_init(struct net_bridge *br)
1610 {
1611 br->hash_elasticity = 4;
1612 br->hash_max = 512;
1613
1614 br->multicast_router = 1;
1615 br->multicast_last_member_count = 2;
1616 br->multicast_startup_query_count = 2;
1617
1618 br->multicast_last_member_interval = HZ;
1619 br->multicast_query_response_interval = 10 * HZ;
1620 br->multicast_startup_query_interval = 125 * HZ / 4;
1621 br->multicast_query_interval = 125 * HZ;
1622 br->multicast_querier_interval = 255 * HZ;
1623 br->multicast_membership_interval = 260 * HZ;
1624
1625 spin_lock_init(&br->multicast_lock);
1626 setup_timer(&br->multicast_router_timer,
1627 br_multicast_local_router_expired, 0);
1628 setup_timer(&br->multicast_querier_timer,
1629 br_multicast_local_router_expired, 0);
1630 setup_timer(&br->multicast_query_timer, br_multicast_query_expired,
1631 (unsigned long)br);
1632 }
1633
br_multicast_open(struct net_bridge * br)1634 void br_multicast_open(struct net_bridge *br)
1635 {
1636 br->multicast_startup_queries_sent = 0;
1637
1638 if (br->multicast_disabled)
1639 return;
1640
1641 mod_timer(&br->multicast_query_timer, jiffies);
1642 }
1643
br_multicast_stop(struct net_bridge * br)1644 void br_multicast_stop(struct net_bridge *br)
1645 {
1646 struct net_bridge_mdb_htable *mdb;
1647 struct net_bridge_mdb_entry *mp;
1648 struct hlist_node *p, *n;
1649 u32 ver;
1650 int i;
1651
1652 del_timer_sync(&br->multicast_router_timer);
1653 del_timer_sync(&br->multicast_querier_timer);
1654 del_timer_sync(&br->multicast_query_timer);
1655
1656 spin_lock_bh(&br->multicast_lock);
1657 mdb = mlock_dereference(br->mdb, br);
1658 if (!mdb)
1659 goto out;
1660
1661 br->mdb = NULL;
1662
1663 ver = mdb->ver;
1664 for (i = 0; i < mdb->max; i++) {
1665 hlist_for_each_entry_safe(mp, p, n, &mdb->mhash[i],
1666 hlist[ver]) {
1667 del_timer(&mp->timer);
1668 del_timer(&mp->query_timer);
1669 call_rcu_bh(&mp->rcu, br_multicast_free_group);
1670 }
1671 }
1672
1673 if (mdb->old) {
1674 spin_unlock_bh(&br->multicast_lock);
1675 rcu_barrier_bh();
1676 spin_lock_bh(&br->multicast_lock);
1677 WARN_ON(mdb->old);
1678 }
1679
1680 mdb->old = mdb;
1681 call_rcu_bh(&mdb->rcu, br_mdb_free);
1682
1683 out:
1684 spin_unlock_bh(&br->multicast_lock);
1685 }
1686
br_multicast_set_router(struct net_bridge * br,unsigned long val)1687 int br_multicast_set_router(struct net_bridge *br, unsigned long val)
1688 {
1689 int err = -ENOENT;
1690
1691 spin_lock_bh(&br->multicast_lock);
1692 if (!netif_running(br->dev))
1693 goto unlock;
1694
1695 switch (val) {
1696 case 0:
1697 case 2:
1698 del_timer(&br->multicast_router_timer);
1699 /* fall through */
1700 case 1:
1701 br->multicast_router = val;
1702 err = 0;
1703 break;
1704
1705 default:
1706 err = -EINVAL;
1707 break;
1708 }
1709
1710 unlock:
1711 spin_unlock_bh(&br->multicast_lock);
1712
1713 return err;
1714 }
1715
br_multicast_set_port_router(struct net_bridge_port * p,unsigned long val)1716 int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
1717 {
1718 struct net_bridge *br = p->br;
1719 int err = -ENOENT;
1720
1721 spin_lock(&br->multicast_lock);
1722 if (!netif_running(br->dev) || p->state == BR_STATE_DISABLED)
1723 goto unlock;
1724
1725 switch (val) {
1726 case 0:
1727 case 1:
1728 case 2:
1729 p->multicast_router = val;
1730 err = 0;
1731
1732 if (val < 2 && !hlist_unhashed(&p->rlist))
1733 hlist_del_init_rcu(&p->rlist);
1734
1735 if (val == 1)
1736 break;
1737
1738 del_timer(&p->multicast_router_timer);
1739
1740 if (val == 0)
1741 break;
1742
1743 br_multicast_add_router(br, p);
1744 break;
1745
1746 default:
1747 err = -EINVAL;
1748 break;
1749 }
1750
1751 unlock:
1752 spin_unlock(&br->multicast_lock);
1753
1754 return err;
1755 }
1756
br_multicast_toggle(struct net_bridge * br,unsigned long val)1757 int br_multicast_toggle(struct net_bridge *br, unsigned long val)
1758 {
1759 struct net_bridge_port *port;
1760 int err = 0;
1761 struct net_bridge_mdb_htable *mdb;
1762
1763 spin_lock(&br->multicast_lock);
1764 if (br->multicast_disabled == !val)
1765 goto unlock;
1766
1767 br->multicast_disabled = !val;
1768 if (br->multicast_disabled)
1769 goto unlock;
1770
1771 if (!netif_running(br->dev))
1772 goto unlock;
1773
1774 mdb = mlock_dereference(br->mdb, br);
1775 if (mdb) {
1776 if (mdb->old) {
1777 err = -EEXIST;
1778 rollback:
1779 br->multicast_disabled = !!val;
1780 goto unlock;
1781 }
1782
1783 err = br_mdb_rehash(&br->mdb, mdb->max,
1784 br->hash_elasticity);
1785 if (err)
1786 goto rollback;
1787 }
1788
1789 br_multicast_open(br);
1790 list_for_each_entry(port, &br->port_list, list) {
1791 if (port->state == BR_STATE_DISABLED ||
1792 port->state == BR_STATE_BLOCKING)
1793 continue;
1794
1795 __br_multicast_enable_port(port);
1796 }
1797
1798 unlock:
1799 spin_unlock(&br->multicast_lock);
1800
1801 return err;
1802 }
1803
br_multicast_set_hash_max(struct net_bridge * br,unsigned long val)1804 int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val)
1805 {
1806 int err = -ENOENT;
1807 u32 old;
1808 struct net_bridge_mdb_htable *mdb;
1809
1810 spin_lock(&br->multicast_lock);
1811 if (!netif_running(br->dev))
1812 goto unlock;
1813
1814 err = -EINVAL;
1815 if (!is_power_of_2(val))
1816 goto unlock;
1817
1818 mdb = mlock_dereference(br->mdb, br);
1819 if (mdb && val < mdb->size)
1820 goto unlock;
1821
1822 err = 0;
1823
1824 old = br->hash_max;
1825 br->hash_max = val;
1826
1827 if (mdb) {
1828 if (mdb->old) {
1829 err = -EEXIST;
1830 rollback:
1831 br->hash_max = old;
1832 goto unlock;
1833 }
1834
1835 err = br_mdb_rehash(&br->mdb, br->hash_max,
1836 br->hash_elasticity);
1837 if (err)
1838 goto rollback;
1839 }
1840
1841 unlock:
1842 spin_unlock(&br->multicast_lock);
1843
1844 return err;
1845 }
1846