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. /* If we have an existing entry, update it's expire timer */
  507. mod_timer(&mp->timer,
  508. jiffies + br->multicast_membership_interval);
  509. goto out;
  510. }
  511. mp = kzalloc(sizeof(*mp), GFP_ATOMIC);
  512. if (unlikely(!mp))
  513. return ERR_PTR(-ENOMEM);
  514. mp->br = br;
  515. mp->addr = *group;
  516. setup_timer(&mp->timer, br_multicast_group_expired,
  517. (unsigned long)mp);
  518. hlist_add_head_rcu(&mp->hlist[mdb->ver], &mdb->mhash[hash]);
  519. mdb->size++;
  520. out:
  521. return mp;
  522. }
  523. struct net_bridge_port_group *br_multicast_new_port_group(
  524. struct net_bridge_port *port,
  525. struct br_ip *group,
  526. struct net_bridge_port_group __rcu *next,
  527. unsigned char state)
  528. {
  529. struct net_bridge_port_group *p;
  530. p = kzalloc(sizeof(*p), GFP_ATOMIC);
  531. if (unlikely(!p))
  532. return NULL;
  533. p->addr = *group;
  534. p->port = port;
  535. p->state = state;
  536. rcu_assign_pointer(p->next, next);
  537. hlist_add_head(&p->mglist, &port->mglist);
  538. setup_timer(&p->timer, br_multicast_port_group_expired,
  539. (unsigned long)p);
  540. return p;
  541. }
  542. static int br_multicast_add_group(struct net_bridge *br,
  543. struct net_bridge_port *port,
  544. struct br_ip *group)
  545. {
  546. struct net_bridge_mdb_entry *mp;
  547. struct net_bridge_port_group *p;
  548. struct net_bridge_port_group __rcu **pp;
  549. int err;
  550. spin_lock(&br->multicast_lock);
  551. if (!netif_running(br->dev) ||
  552. (port && port->state == BR_STATE_DISABLED))
  553. goto out;
  554. mp = br_multicast_new_group(br, port, group);
  555. err = PTR_ERR(mp);
  556. if (IS_ERR(mp))
  557. goto err;
  558. if (!port) {
  559. mp->mglist = true;
  560. goto out;
  561. }
  562. for (pp = &mp->ports;
  563. (p = mlock_dereference(*pp, br)) != NULL;
  564. pp = &p->next) {
  565. if (p->port == port) {
  566. /* We already have a portgroup, update the timer. */
  567. mod_timer(&p->timer,
  568. jiffies + br->multicast_membership_interval);
  569. goto out;
  570. }
  571. if ((unsigned long)p->port < (unsigned long)port)
  572. break;
  573. }
  574. p = br_multicast_new_port_group(port, group, *pp, MDB_TEMPORARY);
  575. if (unlikely(!p))
  576. goto err;
  577. rcu_assign_pointer(*pp, p);
  578. br_mdb_notify(br->dev, port, group, RTM_NEWMDB);
  579. out:
  580. err = 0;
  581. err:
  582. spin_unlock(&br->multicast_lock);
  583. return err;
  584. }
  585. static int br_ip4_multicast_add_group(struct net_bridge *br,
  586. struct net_bridge_port *port,
  587. __be32 group,
  588. __u16 vid)
  589. {
  590. struct br_ip br_group;
  591. if (ipv4_is_local_multicast(group))
  592. return 0;
  593. br_group.u.ip4 = group;
  594. br_group.proto = htons(ETH_P_IP);
  595. br_group.vid = vid;
  596. return br_multicast_add_group(br, port, &br_group);
  597. }
  598. #if IS_ENABLED(CONFIG_IPV6)
  599. static int br_ip6_multicast_add_group(struct net_bridge *br,
  600. struct net_bridge_port *port,
  601. const struct in6_addr *group,
  602. __u16 vid)
  603. {
  604. struct br_ip br_group;
  605. if (ipv6_addr_is_ll_all_nodes(group))
  606. return 0;
  607. br_group.u.ip6 = *group;
  608. br_group.proto = htons(ETH_P_IPV6);
  609. br_group.vid = vid;
  610. return br_multicast_add_group(br, port, &br_group);
  611. }
  612. #endif
  613. static void br_multicast_router_expired(unsigned long data)
  614. {
  615. struct net_bridge_port *port = (void *)data;
  616. struct net_bridge *br = port->br;
  617. spin_lock(&br->multicast_lock);
  618. if (port->multicast_router != 1 ||
  619. timer_pending(&port->multicast_router_timer) ||
  620. hlist_unhashed(&port->rlist))
  621. goto out;
  622. hlist_del_init_rcu(&port->rlist);
  623. out:
  624. spin_unlock(&br->multicast_lock);
  625. }
  626. static void br_multicast_local_router_expired(unsigned long data)
  627. {
  628. }
  629. static void br_multicast_querier_expired(struct net_bridge *br,
  630. struct bridge_mcast_query *query)
  631. {
  632. spin_lock(&br->multicast_lock);
  633. if (!netif_running(br->dev) || br->multicast_disabled)
  634. goto out;
  635. br_multicast_start_querier(br, query);
  636. out:
  637. spin_unlock(&br->multicast_lock);
  638. }
  639. static void br_ip4_multicast_querier_expired(unsigned long data)
  640. {
  641. struct net_bridge *br = (void *)data;
  642. br_multicast_querier_expired(br, &br->ip4_query);
  643. }
  644. #if IS_ENABLED(CONFIG_IPV6)
  645. static void br_ip6_multicast_querier_expired(unsigned long data)
  646. {
  647. struct net_bridge *br = (void *)data;
  648. br_multicast_querier_expired(br, &br->ip6_query);
  649. }
  650. #endif
  651. static void __br_multicast_send_query(struct net_bridge *br,
  652. struct net_bridge_port *port,
  653. struct br_ip *ip)
  654. {
  655. struct sk_buff *skb;
  656. skb = br_multicast_alloc_query(br, ip);
  657. if (!skb)
  658. return;
  659. if (port) {
  660. __skb_push(skb, sizeof(struct ethhdr));
  661. skb->dev = port->dev;
  662. NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
  663. dev_queue_xmit);
  664. } else
  665. netif_rx(skb);
  666. }
  667. static void br_multicast_send_query(struct net_bridge *br,
  668. struct net_bridge_port *port,
  669. struct bridge_mcast_query *query)
  670. {
  671. unsigned long time;
  672. struct br_ip br_group;
  673. struct bridge_mcast_querier *querier = NULL;
  674. if (!netif_running(br->dev) || br->multicast_disabled ||
  675. !br->multicast_querier)
  676. return;
  677. memset(&br_group.u, 0, sizeof(br_group.u));
  678. if (port ? (query == &port->ip4_query) :
  679. (query == &br->ip4_query)) {
  680. querier = &br->ip4_querier;
  681. br_group.proto = htons(ETH_P_IP);
  682. #if IS_ENABLED(CONFIG_IPV6)
  683. } else {
  684. querier = &br->ip6_querier;
  685. br_group.proto = htons(ETH_P_IPV6);
  686. #endif
  687. }
  688. if (!querier || timer_pending(&querier->timer))
  689. return;
  690. __br_multicast_send_query(br, port, &br_group);
  691. time = jiffies;
  692. time += query->startup_sent < br->multicast_startup_query_count ?
  693. br->multicast_startup_query_interval :
  694. br->multicast_query_interval;
  695. mod_timer(&query->timer, time);
  696. }
  697. static void br_multicast_port_query_expired(struct net_bridge_port *port,
  698. struct bridge_mcast_query *query)
  699. {
  700. struct net_bridge *br = port->br;
  701. spin_lock(&br->multicast_lock);
  702. if (port->state == BR_STATE_DISABLED ||
  703. port->state == BR_STATE_BLOCKING)
  704. goto out;
  705. if (query->startup_sent < br->multicast_startup_query_count)
  706. query->startup_sent++;
  707. br_multicast_send_query(port->br, port, query);
  708. out:
  709. spin_unlock(&br->multicast_lock);
  710. }
  711. static void br_ip4_multicast_port_query_expired(unsigned long data)
  712. {
  713. struct net_bridge_port *port = (void *)data;
  714. br_multicast_port_query_expired(port, &port->ip4_query);
  715. }
  716. #if IS_ENABLED(CONFIG_IPV6)
  717. static void br_ip6_multicast_port_query_expired(unsigned long data)
  718. {
  719. struct net_bridge_port *port = (void *)data;
  720. br_multicast_port_query_expired(port, &port->ip6_query);
  721. }
  722. #endif
  723. void br_multicast_add_port(struct net_bridge_port *port)
  724. {
  725. port->multicast_router = 1;
  726. setup_timer(&port->multicast_router_timer, br_multicast_router_expired,
  727. (unsigned long)port);
  728. setup_timer(&port->ip4_query.timer, br_ip4_multicast_port_query_expired,
  729. (unsigned long)port);
  730. #if IS_ENABLED(CONFIG_IPV6)
  731. setup_timer(&port->ip6_query.timer, br_ip6_multicast_port_query_expired,
  732. (unsigned long)port);
  733. #endif
  734. }
  735. void br_multicast_del_port(struct net_bridge_port *port)
  736. {
  737. del_timer_sync(&port->multicast_router_timer);
  738. }
  739. static void br_multicast_enable(struct bridge_mcast_query *query)
  740. {
  741. query->startup_sent = 0;
  742. if (try_to_del_timer_sync(&query->timer) >= 0 ||
  743. del_timer(&query->timer))
  744. mod_timer(&query->timer, jiffies);
  745. }
  746. void br_multicast_enable_port(struct net_bridge_port *port)
  747. {
  748. struct net_bridge *br = port->br;
  749. spin_lock(&br->multicast_lock);
  750. if (br->multicast_disabled || !netif_running(br->dev))
  751. goto out;
  752. br_multicast_enable(&port->ip4_query);
  753. #if IS_ENABLED(CONFIG_IPV6)
  754. br_multicast_enable(&port->ip6_query);
  755. #endif
  756. out:
  757. spin_unlock(&br->multicast_lock);
  758. }
  759. void br_multicast_disable_port(struct net_bridge_port *port)
  760. {
  761. struct net_bridge *br = port->br;
  762. struct net_bridge_port_group *pg;
  763. struct hlist_node *n;
  764. spin_lock(&br->multicast_lock);
  765. hlist_for_each_entry_safe(pg, n, &port->mglist, mglist)
  766. br_multicast_del_pg(br, pg);
  767. if (!hlist_unhashed(&port->rlist))
  768. hlist_del_init_rcu(&port->rlist);
  769. del_timer(&port->multicast_router_timer);
  770. del_timer(&port->ip4_query.timer);
  771. #if IS_ENABLED(CONFIG_IPV6)
  772. del_timer(&port->ip6_query.timer);
  773. #endif
  774. spin_unlock(&br->multicast_lock);
  775. }
  776. static int br_ip4_multicast_igmp3_report(struct net_bridge *br,
  777. struct net_bridge_port *port,
  778. struct sk_buff *skb)
  779. {
  780. struct igmpv3_report *ih;
  781. struct igmpv3_grec *grec;
  782. int i;
  783. int len;
  784. int num;
  785. int type;
  786. int err = 0;
  787. __be32 group;
  788. u16 vid = 0;
  789. if (!pskb_may_pull(skb, sizeof(*ih)))
  790. return -EINVAL;
  791. br_vlan_get_tag(skb, &vid);
  792. ih = igmpv3_report_hdr(skb);
  793. num = ntohs(ih->ngrec);
  794. len = sizeof(*ih);
  795. for (i = 0; i < num; i++) {
  796. len += sizeof(*grec);
  797. if (!pskb_may_pull(skb, len))
  798. return -EINVAL;
  799. grec = (void *)(skb->data + len - sizeof(*grec));
  800. group = grec->grec_mca;
  801. type = grec->grec_type;
  802. len += ntohs(grec->grec_nsrcs) * 4;
  803. if (!pskb_may_pull(skb, len))
  804. return -EINVAL;
  805. /* We treat this as an IGMPv2 report for now. */
  806. switch (type) {
  807. case IGMPV3_MODE_IS_INCLUDE:
  808. case IGMPV3_MODE_IS_EXCLUDE:
  809. case IGMPV3_CHANGE_TO_INCLUDE:
  810. case IGMPV3_CHANGE_TO_EXCLUDE:
  811. case IGMPV3_ALLOW_NEW_SOURCES:
  812. case IGMPV3_BLOCK_OLD_SOURCES:
  813. break;
  814. default:
  815. continue;
  816. }
  817. err = br_ip4_multicast_add_group(br, port, group, vid);
  818. if (err)
  819. break;
  820. }
  821. return err;
  822. }
  823. #if IS_ENABLED(CONFIG_IPV6)
  824. static int br_ip6_multicast_mld2_report(struct net_bridge *br,
  825. struct net_bridge_port *port,
  826. struct sk_buff *skb)
  827. {
  828. struct icmp6hdr *icmp6h;
  829. struct mld2_grec *grec;
  830. int i;
  831. int len;
  832. int num;
  833. int err = 0;
  834. u16 vid = 0;
  835. if (!pskb_may_pull(skb, sizeof(*icmp6h)))
  836. return -EINVAL;
  837. br_vlan_get_tag(skb, &vid);
  838. icmp6h = icmp6_hdr(skb);
  839. num = ntohs(icmp6h->icmp6_dataun.un_data16[1]);
  840. len = sizeof(*icmp6h);
  841. for (i = 0; i < num; i++) {
  842. __be16 *nsrcs, _nsrcs;
  843. nsrcs = skb_header_pointer(skb,
  844. len + offsetof(struct mld2_grec,
  845. grec_nsrcs),
  846. sizeof(_nsrcs), &_nsrcs);
  847. if (!nsrcs)
  848. return -EINVAL;
  849. if (!pskb_may_pull(skb,
  850. len + sizeof(*grec) +
  851. sizeof(struct in6_addr) * ntohs(*nsrcs)))
  852. return -EINVAL;
  853. grec = (struct mld2_grec *)(skb->data + len);
  854. len += sizeof(*grec) +
  855. sizeof(struct in6_addr) * ntohs(*nsrcs);
  856. /* We treat these as MLDv1 reports for now. */
  857. switch (grec->grec_type) {
  858. case MLD2_MODE_IS_INCLUDE:
  859. case MLD2_MODE_IS_EXCLUDE:
  860. case MLD2_CHANGE_TO_INCLUDE:
  861. case MLD2_CHANGE_TO_EXCLUDE:
  862. case MLD2_ALLOW_NEW_SOURCES:
  863. case MLD2_BLOCK_OLD_SOURCES:
  864. break;
  865. default:
  866. continue;
  867. }
  868. err = br_ip6_multicast_add_group(br, port, &grec->grec_mca,
  869. vid);
  870. if (!err)
  871. break;
  872. }
  873. return err;
  874. }
  875. #endif
  876. static void
  877. br_multicast_update_querier_timer(struct net_bridge *br,
  878. struct bridge_mcast_querier *querier,
  879. unsigned long max_delay)
  880. {
  881. if (!timer_pending(&querier->timer))
  882. querier->delay_time = jiffies + max_delay;
  883. mod_timer(&querier->timer, jiffies + br->multicast_querier_interval);
  884. }
  885. /*
  886. * Add port to router_list
  887. * list is maintained ordered by pointer value
  888. * and locked by br->multicast_lock and RCU
  889. */
  890. static void br_multicast_add_router(struct net_bridge *br,
  891. struct net_bridge_port *port)
  892. {
  893. struct net_bridge_port *p;
  894. struct hlist_node *slot = NULL;
  895. hlist_for_each_entry(p, &br->router_list, rlist) {
  896. if ((unsigned long) port >= (unsigned long) p)
  897. break;
  898. slot = &p->rlist;
  899. }
  900. if (slot)
  901. hlist_add_after_rcu(slot, &port->rlist);
  902. else
  903. hlist_add_head_rcu(&port->rlist, &br->router_list);
  904. }
  905. static void br_multicast_mark_router(struct net_bridge *br,
  906. struct net_bridge_port *port)
  907. {
  908. unsigned long now = jiffies;
  909. if (!port) {
  910. if (br->multicast_router == 1)
  911. mod_timer(&br->multicast_router_timer,
  912. now + br->multicast_querier_interval);
  913. return;
  914. }
  915. if (port->multicast_router != 1)
  916. return;
  917. if (!hlist_unhashed(&port->rlist))
  918. goto timer;
  919. br_multicast_add_router(br, port);
  920. timer:
  921. mod_timer(&port->multicast_router_timer,
  922. now + br->multicast_querier_interval);
  923. }
  924. static void br_multicast_query_received(struct net_bridge *br,
  925. struct net_bridge_port *port,
  926. struct bridge_mcast_querier *querier,
  927. int saddr,
  928. unsigned long max_delay)
  929. {
  930. if (saddr)
  931. br_multicast_update_querier_timer(br, querier, max_delay);
  932. else if (timer_pending(&querier->timer))
  933. return;
  934. br_multicast_mark_router(br, port);
  935. }
  936. static int br_ip4_multicast_query(struct net_bridge *br,
  937. struct net_bridge_port *port,
  938. struct sk_buff *skb)
  939. {
  940. const struct iphdr *iph = ip_hdr(skb);
  941. struct igmphdr *ih = igmp_hdr(skb);
  942. struct net_bridge_mdb_entry *mp;
  943. struct igmpv3_query *ih3;
  944. struct net_bridge_port_group *p;
  945. struct net_bridge_port_group __rcu **pp;
  946. unsigned long max_delay;
  947. unsigned long now = jiffies;
  948. __be32 group;
  949. int err = 0;
  950. u16 vid = 0;
  951. spin_lock(&br->multicast_lock);
  952. if (!netif_running(br->dev) ||
  953. (port && port->state == BR_STATE_DISABLED))
  954. goto out;
  955. group = ih->group;
  956. if (skb->len == sizeof(*ih)) {
  957. max_delay = ih->code * (HZ / IGMP_TIMER_SCALE);
  958. if (!max_delay) {
  959. max_delay = 10 * HZ;
  960. group = 0;
  961. }
  962. } else {
  963. if (!pskb_may_pull(skb, sizeof(struct igmpv3_query))) {
  964. err = -EINVAL;
  965. goto out;
  966. }
  967. ih3 = igmpv3_query_hdr(skb);
  968. if (ih3->nsrcs)
  969. goto out;
  970. max_delay = ih3->code ?
  971. IGMPV3_MRC(ih3->code) * (HZ / IGMP_TIMER_SCALE) : 1;
  972. }
  973. br_multicast_query_received(br, port, &br->ip4_querier, !!iph->saddr,
  974. max_delay);
  975. if (!group)
  976. goto out;
  977. br_vlan_get_tag(skb, &vid);
  978. mp = br_mdb_ip4_get(mlock_dereference(br->mdb, br), group, vid);
  979. if (!mp)
  980. goto out;
  981. mod_timer(&mp->timer, now + br->multicast_membership_interval);
  982. mp->timer_armed = true;
  983. max_delay *= br->multicast_last_member_count;
  984. if (mp->mglist &&
  985. (timer_pending(&mp->timer) ?
  986. time_after(mp->timer.expires, now + max_delay) :
  987. try_to_del_timer_sync(&mp->timer) >= 0))
  988. mod_timer(&mp->timer, now + max_delay);
  989. for (pp = &mp->ports;
  990. (p = mlock_dereference(*pp, br)) != NULL;
  991. pp = &p->next) {
  992. if (timer_pending(&p->timer) ?
  993. time_after(p->timer.expires, now + max_delay) :
  994. try_to_del_timer_sync(&p->timer) >= 0)
  995. mod_timer(&p->timer, now + max_delay);
  996. }
  997. out:
  998. spin_unlock(&br->multicast_lock);
  999. return err;
  1000. }
  1001. #if IS_ENABLED(CONFIG_IPV6)
  1002. static int br_ip6_multicast_query(struct net_bridge *br,
  1003. struct net_bridge_port *port,
  1004. struct sk_buff *skb)
  1005. {
  1006. const struct ipv6hdr *ip6h = ipv6_hdr(skb);
  1007. struct mld_msg *mld;
  1008. struct net_bridge_mdb_entry *mp;
  1009. struct mld2_query *mld2q;
  1010. struct net_bridge_port_group *p;
  1011. struct net_bridge_port_group __rcu **pp;
  1012. unsigned long max_delay;
  1013. unsigned long now = jiffies;
  1014. const struct in6_addr *group = NULL;
  1015. int err = 0;
  1016. u16 vid = 0;
  1017. spin_lock(&br->multicast_lock);
  1018. if (!netif_running(br->dev) ||
  1019. (port && port->state == BR_STATE_DISABLED))
  1020. goto out;
  1021. if (skb->len == sizeof(*mld)) {
  1022. if (!pskb_may_pull(skb, sizeof(*mld))) {
  1023. err = -EINVAL;
  1024. goto out;
  1025. }
  1026. mld = (struct mld_msg *) icmp6_hdr(skb);
  1027. max_delay = msecs_to_jiffies(ntohs(mld->mld_maxdelay));
  1028. if (max_delay)
  1029. group = &mld->mld_mca;
  1030. } else {
  1031. if (!pskb_may_pull(skb, sizeof(*mld2q))) {
  1032. err = -EINVAL;
  1033. goto out;
  1034. }
  1035. mld2q = (struct mld2_query *)icmp6_hdr(skb);
  1036. if (!mld2q->mld2q_nsrcs)
  1037. group = &mld2q->mld2q_mca;
  1038. max_delay = max(msecs_to_jiffies(mldv2_mrc(mld2q)), 1UL);
  1039. }
  1040. br_multicast_query_received(br, port, &br->ip6_querier,
  1041. !ipv6_addr_any(&ip6h->saddr), max_delay);
  1042. if (!group)
  1043. goto out;
  1044. br_vlan_get_tag(skb, &vid);
  1045. mp = br_mdb_ip6_get(mlock_dereference(br->mdb, br), group, vid);
  1046. if (!mp)
  1047. goto out;
  1048. mod_timer(&mp->timer, now + br->multicast_membership_interval);
  1049. mp->timer_armed = true;
  1050. max_delay *= br->multicast_last_member_count;
  1051. if (mp->mglist &&
  1052. (timer_pending(&mp->timer) ?
  1053. time_after(mp->timer.expires, now + max_delay) :
  1054. try_to_del_timer_sync(&mp->timer) >= 0))
  1055. mod_timer(&mp->timer, now + max_delay);
  1056. for (pp = &mp->ports;
  1057. (p = mlock_dereference(*pp, br)) != NULL;
  1058. pp = &p->next) {
  1059. if (timer_pending(&p->timer) ?
  1060. time_after(p->timer.expires, now + max_delay) :
  1061. try_to_del_timer_sync(&p->timer) >= 0)
  1062. mod_timer(&p->timer, now + max_delay);
  1063. }
  1064. out:
  1065. spin_unlock(&br->multicast_lock);
  1066. return err;
  1067. }
  1068. #endif
  1069. static void br_multicast_leave_group(struct net_bridge *br,
  1070. struct net_bridge_port *port,
  1071. struct br_ip *group,
  1072. struct bridge_mcast_querier *querier,
  1073. struct bridge_mcast_query *query)
  1074. {
  1075. struct net_bridge_mdb_htable *mdb;
  1076. struct net_bridge_mdb_entry *mp;
  1077. struct net_bridge_port_group *p;
  1078. unsigned long now;
  1079. unsigned long time;
  1080. spin_lock(&br->multicast_lock);
  1081. if (!netif_running(br->dev) ||
  1082. (port && port->state == BR_STATE_DISABLED) ||
  1083. timer_pending(&querier->timer))
  1084. goto out;
  1085. mdb = mlock_dereference(br->mdb, br);
  1086. mp = br_mdb_ip_get(mdb, group);
  1087. if (!mp)
  1088. goto out;
  1089. if (br->multicast_querier) {
  1090. __br_multicast_send_query(br, port, &mp->addr);
  1091. time = jiffies + br->multicast_last_member_count *
  1092. br->multicast_last_member_interval;
  1093. mod_timer(&query->timer, time);
  1094. for (p = mlock_dereference(mp->ports, br);
  1095. p != NULL;
  1096. p = mlock_dereference(p->next, br)) {
  1097. if (p->port != port)
  1098. continue;
  1099. if (!hlist_unhashed(&p->mglist) &&
  1100. (timer_pending(&p->timer) ?
  1101. time_after(p->timer.expires, time) :
  1102. try_to_del_timer_sync(&p->timer) >= 0)) {
  1103. mod_timer(&p->timer, time);
  1104. }
  1105. break;
  1106. }
  1107. }
  1108. if (port && (port->flags & BR_MULTICAST_FAST_LEAVE)) {
  1109. struct net_bridge_port_group __rcu **pp;
  1110. for (pp = &mp->ports;
  1111. (p = mlock_dereference(*pp, br)) != NULL;
  1112. pp = &p->next) {
  1113. if (p->port != port)
  1114. continue;
  1115. rcu_assign_pointer(*pp, p->next);
  1116. hlist_del_init(&p->mglist);
  1117. del_timer(&p->timer);
  1118. call_rcu_bh(&p->rcu, br_multicast_free_pg);
  1119. br_mdb_notify(br->dev, port, group, RTM_DELMDB);
  1120. if (!mp->ports && !mp->mglist && mp->timer_armed &&
  1121. netif_running(br->dev))
  1122. mod_timer(&mp->timer, jiffies);
  1123. }
  1124. goto out;
  1125. }
  1126. now = jiffies;
  1127. time = now + br->multicast_last_member_count *
  1128. br->multicast_last_member_interval;
  1129. if (!port) {
  1130. if (mp->mglist && mp->timer_armed &&
  1131. (timer_pending(&mp->timer) ?
  1132. time_after(mp->timer.expires, time) :
  1133. try_to_del_timer_sync(&mp->timer) >= 0)) {
  1134. mod_timer(&mp->timer, time);
  1135. }
  1136. }
  1137. out:
  1138. spin_unlock(&br->multicast_lock);
  1139. }
  1140. static void br_ip4_multicast_leave_group(struct net_bridge *br,
  1141. struct net_bridge_port *port,
  1142. __be32 group,
  1143. __u16 vid)
  1144. {
  1145. struct br_ip br_group;
  1146. struct bridge_mcast_query *query = port ? &port->ip4_query :
  1147. &br->ip4_query;
  1148. if (ipv4_is_local_multicast(group))
  1149. return;
  1150. br_group.u.ip4 = group;
  1151. br_group.proto = htons(ETH_P_IP);
  1152. br_group.vid = vid;
  1153. br_multicast_leave_group(br, port, &br_group, &br->ip4_querier, query);
  1154. }
  1155. #if IS_ENABLED(CONFIG_IPV6)
  1156. static void br_ip6_multicast_leave_group(struct net_bridge *br,
  1157. struct net_bridge_port *port,
  1158. const struct in6_addr *group,
  1159. __u16 vid)
  1160. {
  1161. struct br_ip br_group;
  1162. struct bridge_mcast_query *query = port ? &port->ip6_query :
  1163. &br->ip6_query;
  1164. if (ipv6_addr_is_ll_all_nodes(group))
  1165. return;
  1166. br_group.u.ip6 = *group;
  1167. br_group.proto = htons(ETH_P_IPV6);
  1168. br_group.vid = vid;
  1169. br_multicast_leave_group(br, port, &br_group, &br->ip6_querier, query);
  1170. }
  1171. #endif
  1172. static int br_multicast_ipv4_rcv(struct net_bridge *br,
  1173. struct net_bridge_port *port,
  1174. struct sk_buff *skb)
  1175. {
  1176. struct sk_buff *skb2 = skb;
  1177. const struct iphdr *iph;
  1178. struct igmphdr *ih;
  1179. unsigned int len;
  1180. unsigned int offset;
  1181. int err;
  1182. u16 vid = 0;
  1183. /* We treat OOM as packet loss for now. */
  1184. if (!pskb_may_pull(skb, sizeof(*iph)))
  1185. return -EINVAL;
  1186. iph = ip_hdr(skb);
  1187. if (iph->ihl < 5 || iph->version != 4)
  1188. return -EINVAL;
  1189. if (!pskb_may_pull(skb, ip_hdrlen(skb)))
  1190. return -EINVAL;
  1191. iph = ip_hdr(skb);
  1192. if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
  1193. return -EINVAL;
  1194. if (iph->protocol != IPPROTO_IGMP) {
  1195. if (!ipv4_is_local_multicast(iph->daddr))
  1196. BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
  1197. return 0;
  1198. }
  1199. len = ntohs(iph->tot_len);
  1200. if (skb->len < len || len < ip_hdrlen(skb))
  1201. return -EINVAL;
  1202. if (skb->len > len) {
  1203. skb2 = skb_clone(skb, GFP_ATOMIC);
  1204. if (!skb2)
  1205. return -ENOMEM;
  1206. err = pskb_trim_rcsum(skb2, len);
  1207. if (err)
  1208. goto err_out;
  1209. }
  1210. len -= ip_hdrlen(skb2);
  1211. offset = skb_network_offset(skb2) + ip_hdrlen(skb2);
  1212. __skb_pull(skb2, offset);
  1213. skb_reset_transport_header(skb2);
  1214. err = -EINVAL;
  1215. if (!pskb_may_pull(skb2, sizeof(*ih)))
  1216. goto out;
  1217. switch (skb2->ip_summed) {
  1218. case CHECKSUM_COMPLETE:
  1219. if (!csum_fold(skb2->csum))
  1220. break;
  1221. /* fall through */
  1222. case CHECKSUM_NONE:
  1223. skb2->csum = 0;
  1224. if (skb_checksum_complete(skb2))
  1225. goto out;
  1226. }
  1227. err = 0;
  1228. br_vlan_get_tag(skb2, &vid);
  1229. BR_INPUT_SKB_CB(skb)->igmp = 1;
  1230. ih = igmp_hdr(skb2);
  1231. switch (ih->type) {
  1232. case IGMP_HOST_MEMBERSHIP_REPORT:
  1233. case IGMPV2_HOST_MEMBERSHIP_REPORT:
  1234. BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
  1235. err = br_ip4_multicast_add_group(br, port, ih->group, vid);
  1236. break;
  1237. case IGMPV3_HOST_MEMBERSHIP_REPORT:
  1238. err = br_ip4_multicast_igmp3_report(br, port, skb2);
  1239. break;
  1240. case IGMP_HOST_MEMBERSHIP_QUERY:
  1241. err = br_ip4_multicast_query(br, port, skb2);
  1242. break;
  1243. case IGMP_HOST_LEAVE_MESSAGE:
  1244. br_ip4_multicast_leave_group(br, port, ih->group, vid);
  1245. break;
  1246. }
  1247. out:
  1248. __skb_push(skb2, offset);
  1249. err_out:
  1250. if (skb2 != skb)
  1251. kfree_skb(skb2);
  1252. return err;
  1253. }
  1254. #if IS_ENABLED(CONFIG_IPV6)
  1255. static int br_multicast_ipv6_rcv(struct net_bridge *br,
  1256. struct net_bridge_port *port,
  1257. struct sk_buff *skb)
  1258. {
  1259. struct sk_buff *skb2;
  1260. const struct ipv6hdr *ip6h;
  1261. u8 icmp6_type;
  1262. u8 nexthdr;
  1263. __be16 frag_off;
  1264. unsigned int len;
  1265. int offset;
  1266. int err;
  1267. u16 vid = 0;
  1268. if (!pskb_may_pull(skb, sizeof(*ip6h)))
  1269. return -EINVAL;
  1270. ip6h = ipv6_hdr(skb);
  1271. /*
  1272. * We're interested in MLD messages only.
  1273. * - Version is 6
  1274. * - MLD has always Router Alert hop-by-hop option
  1275. * - But we do not support jumbrograms.
  1276. */
  1277. if (ip6h->version != 6)
  1278. return 0;
  1279. /* Prevent flooding this packet if there is no listener present */
  1280. if (!ipv6_addr_is_ll_all_nodes(&ip6h->daddr))
  1281. BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
  1282. if (ip6h->nexthdr != IPPROTO_HOPOPTS ||
  1283. ip6h->payload_len == 0)
  1284. return 0;
  1285. len = ntohs(ip6h->payload_len) + sizeof(*ip6h);
  1286. if (skb->len < len)
  1287. return -EINVAL;
  1288. nexthdr = ip6h->nexthdr;
  1289. offset = ipv6_skip_exthdr(skb, sizeof(*ip6h), &nexthdr, &frag_off);
  1290. if (offset < 0 || nexthdr != IPPROTO_ICMPV6)
  1291. return 0;
  1292. /* Okay, we found ICMPv6 header */
  1293. skb2 = skb_clone(skb, GFP_ATOMIC);
  1294. if (!skb2)
  1295. return -ENOMEM;
  1296. err = -EINVAL;
  1297. if (!pskb_may_pull(skb2, offset + sizeof(struct icmp6hdr)))
  1298. goto out;
  1299. len -= offset - skb_network_offset(skb2);
  1300. __skb_pull(skb2, offset);
  1301. skb_reset_transport_header(skb2);
  1302. skb_postpull_rcsum(skb2, skb_network_header(skb2),
  1303. skb_network_header_len(skb2));
  1304. icmp6_type = icmp6_hdr(skb2)->icmp6_type;
  1305. switch (icmp6_type) {
  1306. case ICMPV6_MGM_QUERY:
  1307. case ICMPV6_MGM_REPORT:
  1308. case ICMPV6_MGM_REDUCTION:
  1309. case ICMPV6_MLD2_REPORT:
  1310. break;
  1311. default:
  1312. err = 0;
  1313. goto out;
  1314. }
  1315. /* Okay, we found MLD message. Check further. */
  1316. if (skb2->len > len) {
  1317. err = pskb_trim_rcsum(skb2, len);
  1318. if (err)
  1319. goto out;
  1320. err = -EINVAL;
  1321. }
  1322. ip6h = ipv6_hdr(skb2);
  1323. switch (skb2->ip_summed) {
  1324. case CHECKSUM_COMPLETE:
  1325. if (!csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, skb2->len,
  1326. IPPROTO_ICMPV6, skb2->csum))
  1327. break;
  1328. /*FALLTHROUGH*/
  1329. case CHECKSUM_NONE:
  1330. skb2->csum = ~csum_unfold(csum_ipv6_magic(&ip6h->saddr,
  1331. &ip6h->daddr,
  1332. skb2->len,
  1333. IPPROTO_ICMPV6, 0));
  1334. if (__skb_checksum_complete(skb2))
  1335. goto out;
  1336. }
  1337. err = 0;
  1338. br_vlan_get_tag(skb, &vid);
  1339. BR_INPUT_SKB_CB(skb)->igmp = 1;
  1340. switch (icmp6_type) {
  1341. case ICMPV6_MGM_REPORT:
  1342. {
  1343. struct mld_msg *mld;
  1344. if (!pskb_may_pull(skb2, sizeof(*mld))) {
  1345. err = -EINVAL;
  1346. goto out;
  1347. }
  1348. mld = (struct mld_msg *)skb_transport_header(skb2);
  1349. BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
  1350. err = br_ip6_multicast_add_group(br, port, &mld->mld_mca, vid);
  1351. break;
  1352. }
  1353. case ICMPV6_MLD2_REPORT:
  1354. err = br_ip6_multicast_mld2_report(br, port, skb2);
  1355. break;
  1356. case ICMPV6_MGM_QUERY:
  1357. err = br_ip6_multicast_query(br, port, skb2);
  1358. break;
  1359. case ICMPV6_MGM_REDUCTION:
  1360. {
  1361. struct mld_msg *mld;
  1362. if (!pskb_may_pull(skb2, sizeof(*mld))) {
  1363. err = -EINVAL;
  1364. goto out;
  1365. }
  1366. mld = (struct mld_msg *)skb_transport_header(skb2);
  1367. br_ip6_multicast_leave_group(br, port, &mld->mld_mca, vid);
  1368. }
  1369. }
  1370. out:
  1371. kfree_skb(skb2);
  1372. return err;
  1373. }
  1374. #endif
  1375. int br_multicast_rcv(struct net_bridge *br, struct net_bridge_port *port,
  1376. struct sk_buff *skb)
  1377. {
  1378. BR_INPUT_SKB_CB(skb)->igmp = 0;
  1379. BR_INPUT_SKB_CB(skb)->mrouters_only = 0;
  1380. if (br->multicast_disabled)
  1381. return 0;
  1382. switch (skb->protocol) {
  1383. case htons(ETH_P_IP):
  1384. return br_multicast_ipv4_rcv(br, port, skb);
  1385. #if IS_ENABLED(CONFIG_IPV6)
  1386. case htons(ETH_P_IPV6):
  1387. return br_multicast_ipv6_rcv(br, port, skb);
  1388. #endif
  1389. }
  1390. return 0;
  1391. }
  1392. static void br_multicast_query_expired(struct net_bridge *br,
  1393. struct bridge_mcast_query *query)
  1394. {
  1395. spin_lock(&br->multicast_lock);
  1396. if (query->startup_sent < br->multicast_startup_query_count)
  1397. query->startup_sent++;
  1398. br_multicast_send_query(br, NULL, query);
  1399. spin_unlock(&br->multicast_lock);
  1400. }
  1401. static void br_ip4_multicast_query_expired(unsigned long data)
  1402. {
  1403. struct net_bridge *br = (void *)data;
  1404. br_multicast_query_expired(br, &br->ip4_query);
  1405. }
  1406. #if IS_ENABLED(CONFIG_IPV6)
  1407. static void br_ip6_multicast_query_expired(unsigned long data)
  1408. {
  1409. struct net_bridge *br = (void *)data;
  1410. br_multicast_query_expired(br, &br->ip6_query);
  1411. }
  1412. #endif
  1413. void br_multicast_init(struct net_bridge *br)
  1414. {
  1415. br->hash_elasticity = 4;
  1416. br->hash_max = 512;
  1417. br->multicast_router = 1;
  1418. br->multicast_querier = 0;
  1419. br->multicast_query_use_ifaddr = 0;
  1420. br->multicast_last_member_count = 2;
  1421. br->multicast_startup_query_count = 2;
  1422. br->multicast_last_member_interval = HZ;
  1423. br->multicast_query_response_interval = 10 * HZ;
  1424. br->multicast_startup_query_interval = 125 * HZ / 4;
  1425. br->multicast_query_interval = 125 * HZ;
  1426. br->multicast_querier_interval = 255 * HZ;
  1427. br->multicast_membership_interval = 260 * HZ;
  1428. br->ip4_querier.delay_time = 0;
  1429. #if IS_ENABLED(CONFIG_IPV6)
  1430. br->ip6_querier.delay_time = 0;
  1431. #endif
  1432. spin_lock_init(&br->multicast_lock);
  1433. setup_timer(&br->multicast_router_timer,
  1434. br_multicast_local_router_expired, 0);
  1435. setup_timer(&br->ip4_querier.timer, br_ip4_multicast_querier_expired,
  1436. (unsigned long)br);
  1437. setup_timer(&br->ip4_query.timer, br_ip4_multicast_query_expired,
  1438. (unsigned long)br);
  1439. #if IS_ENABLED(CONFIG_IPV6)
  1440. setup_timer(&br->ip6_querier.timer, br_ip6_multicast_querier_expired,
  1441. (unsigned long)br);
  1442. setup_timer(&br->ip6_query.timer, br_ip6_multicast_query_expired,
  1443. (unsigned long)br);
  1444. #endif
  1445. }
  1446. static void __br_multicast_open(struct net_bridge *br,
  1447. struct bridge_mcast_query *query)
  1448. {
  1449. query->startup_sent = 0;
  1450. if (br->multicast_disabled)
  1451. return;
  1452. mod_timer(&query->timer, jiffies);
  1453. }
  1454. void br_multicast_open(struct net_bridge *br)
  1455. {
  1456. __br_multicast_open(br, &br->ip4_query);
  1457. #if IS_ENABLED(CONFIG_IPV6)
  1458. __br_multicast_open(br, &br->ip6_query);
  1459. #endif
  1460. }
  1461. void br_multicast_stop(struct net_bridge *br)
  1462. {
  1463. struct net_bridge_mdb_htable *mdb;
  1464. struct net_bridge_mdb_entry *mp;
  1465. struct hlist_node *n;
  1466. u32 ver;
  1467. int i;
  1468. del_timer_sync(&br->multicast_router_timer);
  1469. del_timer_sync(&br->ip4_querier.timer);
  1470. del_timer_sync(&br->ip4_query.timer);
  1471. #if IS_ENABLED(CONFIG_IPV6)
  1472. del_timer_sync(&br->ip6_querier.timer);
  1473. del_timer_sync(&br->ip6_query.timer);
  1474. #endif
  1475. spin_lock_bh(&br->multicast_lock);
  1476. mdb = mlock_dereference(br->mdb, br);
  1477. if (!mdb)
  1478. goto out;
  1479. br->mdb = NULL;
  1480. ver = mdb->ver;
  1481. for (i = 0; i < mdb->max; i++) {
  1482. hlist_for_each_entry_safe(mp, n, &mdb->mhash[i],
  1483. hlist[ver]) {
  1484. del_timer(&mp->timer);
  1485. mp->timer_armed = false;
  1486. call_rcu_bh(&mp->rcu, br_multicast_free_group);
  1487. }
  1488. }
  1489. if (mdb->old) {
  1490. spin_unlock_bh(&br->multicast_lock);
  1491. rcu_barrier_bh();
  1492. spin_lock_bh(&br->multicast_lock);
  1493. WARN_ON(mdb->old);
  1494. }
  1495. mdb->old = mdb;
  1496. call_rcu_bh(&mdb->rcu, br_mdb_free);
  1497. out:
  1498. spin_unlock_bh(&br->multicast_lock);
  1499. }
  1500. int br_multicast_set_router(struct net_bridge *br, unsigned long val)
  1501. {
  1502. int err = -ENOENT;
  1503. spin_lock_bh(&br->multicast_lock);
  1504. if (!netif_running(br->dev))
  1505. goto unlock;
  1506. switch (val) {
  1507. case 0:
  1508. case 2:
  1509. del_timer(&br->multicast_router_timer);
  1510. /* fall through */
  1511. case 1:
  1512. br->multicast_router = val;
  1513. err = 0;
  1514. break;
  1515. default:
  1516. err = -EINVAL;
  1517. break;
  1518. }
  1519. unlock:
  1520. spin_unlock_bh(&br->multicast_lock);
  1521. return err;
  1522. }
  1523. int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
  1524. {
  1525. struct net_bridge *br = p->br;
  1526. int err = -ENOENT;
  1527. spin_lock(&br->multicast_lock);
  1528. if (!netif_running(br->dev) || p->state == BR_STATE_DISABLED)
  1529. goto unlock;
  1530. switch (val) {
  1531. case 0:
  1532. case 1:
  1533. case 2:
  1534. p->multicast_router = val;
  1535. err = 0;
  1536. if (val < 2 && !hlist_unhashed(&p->rlist))
  1537. hlist_del_init_rcu(&p->rlist);
  1538. if (val == 1)
  1539. break;
  1540. del_timer(&p->multicast_router_timer);
  1541. if (val == 0)
  1542. break;
  1543. br_multicast_add_router(br, p);
  1544. break;
  1545. default:
  1546. err = -EINVAL;
  1547. break;
  1548. }
  1549. unlock:
  1550. spin_unlock(&br->multicast_lock);
  1551. return err;
  1552. }
  1553. static void br_multicast_start_querier(struct net_bridge *br,
  1554. struct bridge_mcast_query *query)
  1555. {
  1556. struct net_bridge_port *port;
  1557. __br_multicast_open(br, query);
  1558. list_for_each_entry(port, &br->port_list, list) {
  1559. if (port->state == BR_STATE_DISABLED ||
  1560. port->state == BR_STATE_BLOCKING)
  1561. continue;
  1562. if (query == &br->ip4_query)
  1563. br_multicast_enable(&port->ip4_query);
  1564. #if IS_ENABLED(CONFIG_IPV6)
  1565. else
  1566. br_multicast_enable(&port->ip6_query);
  1567. #endif
  1568. }
  1569. }
  1570. int br_multicast_toggle(struct net_bridge *br, unsigned long val)
  1571. {
  1572. int err = 0;
  1573. struct net_bridge_mdb_htable *mdb;
  1574. spin_lock_bh(&br->multicast_lock);
  1575. if (br->multicast_disabled == !val)
  1576. goto unlock;
  1577. br->multicast_disabled = !val;
  1578. if (br->multicast_disabled)
  1579. goto unlock;
  1580. if (!netif_running(br->dev))
  1581. goto unlock;
  1582. mdb = mlock_dereference(br->mdb, br);
  1583. if (mdb) {
  1584. if (mdb->old) {
  1585. err = -EEXIST;
  1586. rollback:
  1587. br->multicast_disabled = !!val;
  1588. goto unlock;
  1589. }
  1590. err = br_mdb_rehash(&br->mdb, mdb->max,
  1591. br->hash_elasticity);
  1592. if (err)
  1593. goto rollback;
  1594. }
  1595. br_multicast_start_querier(br, &br->ip4_query);
  1596. #if IS_ENABLED(CONFIG_IPV6)
  1597. br_multicast_start_querier(br, &br->ip6_query);
  1598. #endif
  1599. unlock:
  1600. spin_unlock_bh(&br->multicast_lock);
  1601. return err;
  1602. }
  1603. int br_multicast_set_querier(struct net_bridge *br, unsigned long val)
  1604. {
  1605. unsigned long max_delay;
  1606. val = !!val;
  1607. spin_lock_bh(&br->multicast_lock);
  1608. if (br->multicast_querier == val)
  1609. goto unlock;
  1610. br->multicast_querier = val;
  1611. if (!val)
  1612. goto unlock;
  1613. max_delay = br->multicast_query_response_interval;
  1614. if (!timer_pending(&br->ip4_querier.timer))
  1615. br->ip4_querier.delay_time = jiffies + max_delay;
  1616. br_multicast_start_querier(br, &br->ip4_query);
  1617. #if IS_ENABLED(CONFIG_IPV6)
  1618. if (!timer_pending(&br->ip6_querier.timer))
  1619. br->ip6_querier.delay_time = jiffies + max_delay;
  1620. br_multicast_start_querier(br, &br->ip6_query);
  1621. #endif
  1622. unlock:
  1623. spin_unlock_bh(&br->multicast_lock);
  1624. return 0;
  1625. }
  1626. int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val)
  1627. {
  1628. int err = -ENOENT;
  1629. u32 old;
  1630. struct net_bridge_mdb_htable *mdb;
  1631. spin_lock(&br->multicast_lock);
  1632. if (!netif_running(br->dev))
  1633. goto unlock;
  1634. err = -EINVAL;
  1635. if (!is_power_of_2(val))
  1636. goto unlock;
  1637. mdb = mlock_dereference(br->mdb, br);
  1638. if (mdb && val < mdb->size)
  1639. goto unlock;
  1640. err = 0;
  1641. old = br->hash_max;
  1642. br->hash_max = val;
  1643. if (mdb) {
  1644. if (mdb->old) {
  1645. err = -EEXIST;
  1646. rollback:
  1647. br->hash_max = old;
  1648. goto unlock;
  1649. }
  1650. err = br_mdb_rehash(&br->mdb, br->hash_max,
  1651. br->hash_elasticity);
  1652. if (err)
  1653. goto rollback;
  1654. }
  1655. unlock:
  1656. spin_unlock(&br->multicast_lock);
  1657. return err;
  1658. }