br_multicast.c 44 KB

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