net/bridge/br_multicast.c

   1 /*
   2  * Bridge multicast support.
   3  *
   4  * Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au>
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the Free
   8  * Software Foundation; either version 2 of the License, or (at your option)
   9  * any later version.
  10  *
  11  */
  12
  13 #include <linux/err.h>
  14 #include <linux/if_ether.h>
  15 #include <linux/igmp.h>
  16 #include <linux/jhash.h>
  17 #include <linux/kernel.h>
  18 #include <linux/log2.h>
  19 #include <linux/netdevice.h>
  20 #include <linux/netfilter_bridge.h>
  21 #include <linux/random.h>
  22 #include <linux/rculist.h>
  23 #include <linux/skbuff.h>
  24 #include <linux/slab.h>
  25 #include <linux/timer.h>
  26 #include <net/ip.h>
  27 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
  28 #include <net/ipv6.h>
  29 #include <net/mld.h>
  30 #include <net/addrconf.h>
  31 #include <net/ip6_checksum.h>
  32 #endif
  33
  34 #include "br_private.h"
  35
  36 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
  37 static inline int ipv6_is_local_multicast(const struct in6_addr *addr)
  38 {
  39         if (ipv6_addr_is_multicast(addr) &&
  40             IPV6_ADDR_MC_SCOPE(addr) <= IPV6_ADDR_SCOPE_LINKLOCAL)
  41                 return 1;
  42         return 0;
  43 }
  44 #endif
  45
  46 static inline int br_ip_equal(const struct br_ip *a, const struct br_ip *b)
  47 {
  48         if (a->proto != b->proto)
  49                 return 0;
  50         switch (a->proto) {
  51         case htons(ETH_P_IP):
  52                 return a->u.ip4 == b->u.ip4;
  53 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
  54         case htons(ETH_P_IPV6):
  55                 return ipv6_addr_equal(&a->u.ip6, &b->u.ip6);
  56 #endif
  57         }
  58         return 0;
  59 }
  60
  61 static inline int __br_ip4_hash(struct net_bridge_mdb_htable *mdb, __be32 ip)
  62 {
  63         return jhash_1word(mdb->secret, (__force u32)ip) & (mdb->max - 1);
  64 }
  65
  66 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
  67 static inline int __br_ip6_hash(struct net_bridge_mdb_htable *mdb,
  68                                 const struct in6_addr *ip)
  69 {
  70         return jhash2((__force u32 *)ip->s6_addr32, 4, mdb->secret) & (mdb->max - 1);
  71 }
  72 #endif
  73
  74 static inline int br_ip_hash(struct net_bridge_mdb_htable *mdb,
  75                              struct br_ip *ip)
  76 {
  77         switch (ip->proto) {
  78         case htons(ETH_P_IP):
  79                 return __br_ip4_hash(mdb, ip->u.ip4);
  80 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
  81         case htons(ETH_P_IPV6):
  82                 return __br_ip6_hash(mdb, &ip->u.ip6);
  83 #endif
  84         }
  85         return 0;
  86 }
  87
  88 static struct net_bridge_mdb_entry *__br_mdb_ip_get(
  89         struct net_bridge_mdb_htable *mdb, struct br_ip *dst, int hash)
  90 {
  91         struct net_bridge_mdb_entry *mp;
  92         struct hlist_node *p;
  93
  94         hlist_for_each_entry_rcu(mp, p, &mdb->mhash[hash], hlist[mdb->ver]) {
  95                 if (br_ip_equal(&mp->addr, dst))
  96                         return mp;
  97         }
  98
  99         return NULL;
 100 }
 101
 102 static struct net_bridge_mdb_entry *br_mdb_ip_get(
 103         struct net_bridge_mdb_htable *mdb, struct br_ip *dst)
 104 {
 105         if (!mdb)
 106                 return NULL;
 107
 108         return __br_mdb_ip_get(mdb, dst, br_ip_hash(mdb, dst));
 109 }
 110
 111 static struct net_bridge_mdb_entry *br_mdb_ip4_get(
 112         struct net_bridge_mdb_htable *mdb, __be32 dst)
 113 {
 114         struct br_ip br_dst;
 115
 116         br_dst.u.ip4 = dst;
 117         br_dst.proto = htons(ETH_P_IP);
 118
 119         return br_mdb_ip_get(mdb, &br_dst);
 120 }
 121
 122 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 123 static struct net_bridge_mdb_entry *br_mdb_ip6_get(
 124         struct net_bridge_mdb_htable *mdb, const struct in6_addr *dst)
 125 {
 126         struct br_ip br_dst;
 127
 128         ipv6_addr_copy(&br_dst.u.ip6, dst);
 129         br_dst.proto = htons(ETH_P_IPV6);
 130
 131         return br_mdb_ip_get(mdb, &br_dst);
 132 }
 133 #endif
 134
 135 struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br,
 136                                         struct sk_buff *skb)
 137 {
 138         struct net_bridge_mdb_htable *mdb = br->mdb;
 139         struct br_ip ip;
 140
 141         if (br->multicast_disabled)
 142                 return NULL;
 143
 144         if (BR_INPUT_SKB_CB(skb)->igmp)
 145                 return NULL;
 146
 147         ip.proto = skb->protocol;
 148
 149         switch (skb->protocol) {
 150         case htons(ETH_P_IP):
 151                 ip.u.ip4 = ip_hdr(skb)->daddr;
 152                 break;
 153 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 154         case htons(ETH_P_IPV6):
 155                 ipv6_addr_copy(&ip.u.ip6, &ipv6_hdr(skb)->daddr);
 156                 break;
 157 #endif
 158         default:
 159                 return NULL;
 160         }
 161
 162         return br_mdb_ip_get(mdb, &ip);
 163 }
 164
 165 static void br_mdb_free(struct rcu_head *head)
 166 {
 167         struct net_bridge_mdb_htable *mdb =
 168                 container_of(head, struct net_bridge_mdb_htable, rcu);
 169         struct net_bridge_mdb_htable *old = mdb->old;
 170
 171         mdb->old = NULL;
 172         kfree(old->mhash);
 173         kfree(old);
 174 }
 175
 176 static int br_mdb_copy(struct net_bridge_mdb_htable *new,
 177                        struct net_bridge_mdb_htable *old,
 178                        int elasticity)
 179 {
 180         struct net_bridge_mdb_entry *mp;
 181         struct hlist_node *p;
 182         int maxlen;
 183         int len;
 184         int i;
 185
 186         for (i = 0; i < old->max; i++)
 187                 hlist_for_each_entry(mp, p, &old->mhash[i], hlist[old->ver])
 188                         hlist_add_head(&mp->hlist[new->ver],
 189                                        &new->mhash[br_ip_hash(new, &mp->addr)]);
 190
 191         if (!elasticity)
 192                 return 0;
 193
 194         maxlen = 0;
 195         for (i = 0; i < new->max; i++) {
 196                 len = 0;
 197                 hlist_for_each_entry(mp, p, &new->mhash[i], hlist[new->ver])
 198                         len++;
 199                 if (len > maxlen)
 200                         maxlen = len;
 201         }
 202
 203         return maxlen > elasticity ? -EINVAL : 0;
 204 }
 205
 206 static void br_multicast_free_pg(struct rcu_head *head)
 207 {
 208         struct net_bridge_port_group *p =
 209                 container_of(head, struct net_bridge_port_group, rcu);
 210
 211         kfree(p);
 212 }
 213
 214 static void br_multicast_free_group(struct rcu_head *head)
 215 {
 216         struct net_bridge_mdb_entry *mp =
 217                 container_of(head, struct net_bridge_mdb_entry, rcu);
 218
 219         kfree(mp);
 220 }
 221
 222 static void br_multicast_group_expired(unsigned long data)
 223 {
 224         struct net_bridge_mdb_entry *mp = (void *)data;
 225         struct net_bridge *br = mp->br;
 226         struct net_bridge_mdb_htable *mdb;
 227
 228         spin_lock(&br->multicast_lock);
 229         if (!netif_running(br->dev) || timer_pending(&mp->timer))
 230                 goto out;
 231
 232         if (!hlist_unhashed(&mp->mglist))
 233                 hlist_del_init(&mp->mglist);
 234
 235         if (mp->ports)
 236                 goto out;
 237
 238         mdb = br->mdb;
 239         hlist_del_rcu(&mp->hlist[mdb->ver]);
 240         mdb->size--;
 241
 242         del_timer(&mp->query_timer);
 243         call_rcu_bh(&mp->rcu, br_multicast_free_group);
 244
 245 out:
 246         spin_unlock(&br->multicast_lock);
 247 }
 248
 249 static void br_multicast_del_pg(struct net_bridge *br,
 250                                 struct net_bridge_port_group *pg)
 251 {
 252         struct net_bridge_mdb_htable *mdb = br->mdb;
 253         struct net_bridge_mdb_entry *mp;
 254         struct net_bridge_port_group *p;
 255         struct net_bridge_port_group **pp;
 256
 257         mp = br_mdb_ip_get(mdb, &pg->addr);
 258         if (WARN_ON(!mp))
 259                 return;
 260
 261         for (pp = &mp->ports; (p = *pp); pp = &p->next) {
 262                 if (p != pg)
 263                         continue;
 264
 265                 rcu_assign_pointer(*pp, p->next);
 266                 hlist_del_init(&p->mglist);
 267                 del_timer(&p->timer);
 268                 del_timer(&p->query_timer);
 269                 call_rcu_bh(&p->rcu, br_multicast_free_pg);
 270
 271                 if (!mp->ports && hlist_unhashed(&mp->mglist) &&
 272                     netif_running(br->dev))
 273                         mod_timer(&mp->timer, jiffies);
 274
 275                 return;
 276         }
 277
 278         WARN_ON(1);
 279 }
 280
 281 static void br_multicast_port_group_expired(unsigned long data)
 282 {
 283         struct net_bridge_port_group *pg = (void *)data;
 284         struct net_bridge *br = pg->port->br;
 285
 286         spin_lock(&br->multicast_lock);
 287         if (!netif_running(br->dev) || timer_pending(&pg->timer) ||
 288             hlist_unhashed(&pg->mglist))
 289                 goto out;
 290
 291         br_multicast_del_pg(br, pg);
 292
 293 out:
 294         spin_unlock(&br->multicast_lock);
 295 }
 296
 297 static int br_mdb_rehash(struct net_bridge_mdb_htable **mdbp, int max,
 298                          int elasticity)
 299 {
 300         struct net_bridge_mdb_htable *old = *mdbp;
 301         struct net_bridge_mdb_htable *mdb;
 302         int err;
 303
 304         mdb = kmalloc(sizeof(*mdb), GFP_ATOMIC);
 305         if (!mdb)
 306                 return -ENOMEM;
 307
 308         mdb->max = max;
 309         mdb->old = old;
 310
 311         mdb->mhash = kzalloc(max * sizeof(*mdb->mhash), GFP_ATOMIC);
 312         if (!mdb->mhash) {
 313                 kfree(mdb);
 314                 return -ENOMEM;
 315         }
 316
 317         mdb->size = old ? old->size : 0;
 318         mdb->ver = old ? old->ver ^ 1 : 0;
 319
 320         if (!old || elasticity)
 321                 get_random_bytes(&mdb->secret, sizeof(mdb->secret));
 322         else
 323                 mdb->secret = old->secret;
 324
 325         if (!old)
 326                 goto out;
 327
 328         err = br_mdb_copy(mdb, old, elasticity);
 329         if (err) {
 330                 kfree(mdb->mhash);
 331                 kfree(mdb);
 332                 return err;
 333         }
 334
 335         call_rcu_bh(&mdb->rcu, br_mdb_free);
 336
 337 out:
 338         rcu_assign_pointer(*mdbp, mdb);
 339
 340         return 0;
 341 }
 342
 343 static struct sk_buff *br_ip4_multicast_alloc_query(struct net_bridge *br,
 344                                                     __be32 group)
 345 {
 346         struct sk_buff *skb;
 347         struct igmphdr *ih;
 348         struct ethhdr *eth;
 349         struct iphdr *iph;
 350
 351         skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*iph) +
 352                                                  sizeof(*ih) + 4);
 353         if (!skb)
 354                 goto out;
 355
 356         skb->protocol = htons(ETH_P_IP);
 357
 358         skb_reset_mac_header(skb);
 359         eth = eth_hdr(skb);
 360
 361         memcpy(eth->h_source, br->dev->dev_addr, 6);
 362         eth->h_dest[0] = 1;
 363         eth->h_dest[1] = 0;
 364         eth->h_dest[2] = 0x5e;
 365         eth->h_dest[3] = 0;
 366         eth->h_dest[4] = 0;
 367         eth->h_dest[5] = 1;
 368         eth->h_proto = htons(ETH_P_IP);
 369         skb_put(skb, sizeof(*eth));
 370
 371         skb_set_network_header(skb, skb->len);
 372         iph = ip_hdr(skb);
 373
 374         iph->version = 4;
 375         iph->ihl = 6;
 376         iph->tos = 0xc0;
 377         iph->tot_len = htons(sizeof(*iph) + sizeof(*ih) + 4);
 378         iph->id = 0;
 379         iph->frag_off = htons(IP_DF);
 380         iph->ttl = 1;
 381         iph->protocol = IPPROTO_IGMP;
 382         iph->saddr = 0;
 383         iph->daddr = htonl(INADDR_ALLHOSTS_GROUP);
 384         ((u8 *)&iph[1])[0] = IPOPT_RA;
 385         ((u8 *)&iph[1])[1] = 4;
 386         ((u8 *)&iph[1])[2] = 0;
 387         ((u8 *)&iph[1])[3] = 0;
 388         ip_send_check(iph);
 389         skb_put(skb, 24);
 390
 391         skb_set_transport_header(skb, skb->len);
 392         ih = igmp_hdr(skb);
 393         ih->type = IGMP_HOST_MEMBERSHIP_QUERY;
 394         ih->code = (group ? br->multicast_last_member_interval :
 395                             br->multicast_query_response_interval) /
 396                    (HZ / IGMP_TIMER_SCALE);
 397         ih->group = group;
 398         ih->csum = 0;
 399         ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
 400         skb_put(skb, sizeof(*ih));
 401
 402         __skb_pull(skb, sizeof(*eth));
 403
 404 out:
 405         return skb;
 406 }
 407
 408 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 409 static struct sk_buff *br_ip6_multicast_alloc_query(struct net_bridge *br,
 410                                                     struct in6_addr *group)
 411 {
 412         struct sk_buff *skb;
 413         struct ipv6hdr *ip6h;
 414         struct mld_msg *mldq;
 415         struct ethhdr *eth;
 416         u8 *hopopt;
 417         unsigned long interval;
 418
 419         skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*ip6h) +
 420                                                  8 + sizeof(*mldq));
 421         if (!skb)
 422                 goto out;
 423
 424         skb->protocol = htons(ETH_P_IPV6);
 425
 426         /* Ethernet header */
 427         skb_reset_mac_header(skb);
 428         eth = eth_hdr(skb);
 429
 430         memcpy(eth->h_source, br->dev->dev_addr, 6);
 431         ipv6_eth_mc_map(group, eth->h_dest);
 432         eth->h_proto = htons(ETH_P_IPV6);
 433         skb_put(skb, sizeof(*eth));
 434
 435         /* IPv6 header + HbH option */
 436         skb_set_network_header(skb, skb->len);
 437         ip6h = ipv6_hdr(skb);
 438
 439         *(__force __be32 *)ip6h = htonl(0x60000000);
 440         ip6h->payload_len = 8 + sizeof(*mldq);
 441         ip6h->nexthdr = IPPROTO_HOPOPTS;
 442         ip6h->hop_limit = 1;
 443         ipv6_addr_set(&ip6h->saddr, 0, 0, 0, 0);
 444         ipv6_addr_set(&ip6h->daddr, htonl(0xff020000), 0, 0, htonl(1));
 445
 446         hopopt = (u8 *)(ip6h + 1);
 447         hopopt[0] = IPPROTO_ICMPV6;             /* next hdr */
 448         hopopt[1] = 0;                          /* length of HbH */
 449         hopopt[2] = IPV6_TLV_ROUTERALERT;       /* Router Alert */
 450         hopopt[3] = 2;                          /* Length of RA Option */
 451         hopopt[4] = 0;                          /* Type = 0x0000 (MLD) */
 452         hopopt[5] = 0;
 453         hopopt[6] = IPV6_TLV_PAD0;              /* Pad0 */
 454         hopopt[7] = IPV6_TLV_PAD0;              /* Pad0 */
 455
 456         skb_put(skb, sizeof(*ip6h) + 8);
 457
 458         /* ICMPv6 */
 459         skb_set_transport_header(skb, skb->len);
 460         mldq = (struct mld_msg *) icmp6_hdr(skb);
 461
 462         interval = ipv6_addr_any(group) ? br->multicast_last_member_interval :
 463                                           br->multicast_query_response_interval;
 464
 465         mldq->mld_type = ICMPV6_MGM_QUERY;
 466         mldq->mld_code = 0;
 467         mldq->mld_cksum = 0;
 468         mldq->mld_maxdelay = htons((u16)jiffies_to_msecs(interval));
 469         mldq->mld_reserved = 0;
 470         ipv6_addr_copy(&mldq->mld_mca, group);
 471
 472         /* checksum */
 473         mldq->mld_cksum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
 474                                           sizeof(*mldq), IPPROTO_ICMPV6,
 475                                           csum_partial(mldq,
 476                                                        sizeof(*mldq), 0));
 477         skb_put(skb, sizeof(*mldq));
 478
 479         __skb_pull(skb, sizeof(*eth));
 480
 481 out:
 482         return skb;
 483 }
 484 #endif
 485
 486 static struct sk_buff *br_multicast_alloc_query(struct net_bridge *br,
 487                                                 struct br_ip *addr)
 488 {
 489         switch (addr->proto) {
 490         case htons(ETH_P_IP):
 491                 return br_ip4_multicast_alloc_query(br, addr->u.ip4);
 492 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 493         case htons(ETH_P_IPV6):
 494                 return br_ip6_multicast_alloc_query(br, &addr->u.ip6);
 495 #endif
 496         }
 497         return NULL;
 498 }
 499
 500 static void br_multicast_send_group_query(struct net_bridge_mdb_entry *mp)
 501 {
 502         struct net_bridge *br = mp->br;
 503         struct sk_buff *skb;
 504
 505         skb = br_multicast_alloc_query(br, &mp->addr);
 506         if (!skb)
 507                 goto timer;
 508
 509         netif_rx(skb);
 510
 511 timer:
 512         if (++mp->queries_sent < br->multicast_last_member_count)
 513                 mod_timer(&mp->query_timer,
 514                           jiffies + br->multicast_last_member_interval);
 515 }
 516
 517 static void br_multicast_group_query_expired(unsigned long data)
 518 {
 519         struct net_bridge_mdb_entry *mp = (void *)data;
 520         struct net_bridge *br = mp->br;
 521
 522         spin_lock(&br->multicast_lock);
 523         if (!netif_running(br->dev) || hlist_unhashed(&mp->mglist) ||
 524             mp->queries_sent >= br->multicast_last_member_count)
 525                 goto out;
 526
 527         br_multicast_send_group_query(mp);
 528
 529 out:
 530         spin_unlock(&br->multicast_lock);
 531 }
 532
 533 static void br_multicast_send_port_group_query(struct net_bridge_port_group *pg)
 534 {
 535         struct net_bridge_port *port = pg->port;
 536         struct net_bridge *br = port->br;
 537         struct sk_buff *skb;
 538
 539         skb = br_multicast_alloc_query(br, &pg->addr);
 540         if (!skb)
 541                 goto timer;
 542
 543         br_deliver(port, skb);
 544
 545 timer:
 546         if (++pg->queries_sent < br->multicast_last_member_count)
 547                 mod_timer(&pg->query_timer,
 548                           jiffies + br->multicast_last_member_interval);
 549 }
 550
 551 static void br_multicast_port_group_query_expired(unsigned long data)
 552 {
 553         struct net_bridge_port_group *pg = (void *)data;
 554         struct net_bridge_port *port = pg->port;
 555         struct net_bridge *br = port->br;
 556
 557         spin_lock(&br->multicast_lock);
 558         if (!netif_running(br->dev) || hlist_unhashed(&pg->mglist) ||
 559             pg->queries_sent >= br->multicast_last_member_count)
 560                 goto out;
 561
 562         br_multicast_send_port_group_query(pg);
 563
 564 out:
 565         spin_unlock(&br->multicast_lock);
 566 }
 567
 568 static struct net_bridge_mdb_entry *br_multicast_get_group(
 569         struct net_bridge *br, struct net_bridge_port *port,
 570         struct br_ip *group, int hash)
 571 {
 572         struct net_bridge_mdb_htable *mdb = br->mdb;
 573         struct net_bridge_mdb_entry *mp;
 574         struct hlist_node *p;
 575         unsigned count = 0;
 576         unsigned max;
 577         int elasticity;
 578         int err;
 579
 580         hlist_for_each_entry(mp, p, &mdb->mhash[hash], hlist[mdb->ver]) {
 581                 count++;
 582                 if (unlikely(br_ip_equal(group, &mp->addr)))
 583                         return mp;
 584         }
 585
 586         elasticity = 0;
 587         max = mdb->max;
 588
 589         if (unlikely(count > br->hash_elasticity && count)) {
 590                 if (net_ratelimit())
 591                         br_info(br, "Multicast hash table "
 592                                 "chain limit reached: %s\n",
 593                                 port ? port->dev->name : br->dev->name);
 594
 595                 elasticity = br->hash_elasticity;
 596         }
 597
 598         if (mdb->size >= max) {
 599                 max *= 2;
 600                 if (unlikely(max >= br->hash_max)) {
 601                         br_warn(br, "Multicast hash table maximum "
 602                                 "reached, disabling snooping: %s, %d\n",
 603                                 port ? port->dev->name : br->dev->name, max);
 604                         err = -E2BIG;
 605 disable:
 606                         br->multicast_disabled = 1;
 607                         goto err;
 608                 }
 609         }
 610
 611         if (max > mdb->max || elasticity) {
 612                 if (mdb->old) {
 613                         if (net_ratelimit())
 614                                 br_info(br, "Multicast hash table "
 615                                         "on fire: %s\n",
 616                                         port ? port->dev->name : br->dev->name);
 617                         err = -EEXIST;
 618                         goto err;
 619                 }
 620
 621                 err = br_mdb_rehash(&br->mdb, max, elasticity);
 622                 if (err) {
 623                         br_warn(br, "Cannot rehash multicast "
 624                                 "hash table, disabling snooping: %s, %d, %d\n",
 625                                 port ? port->dev->name : br->dev->name,
 626                                 mdb->size, err);
 627                         goto disable;
 628                 }
 629
 630                 err = -EAGAIN;
 631                 goto err;
 632         }
 633
 634         return NULL;
 635
 636 err:
 637         mp = ERR_PTR(err);
 638         return mp;
 639 }
 640
 641 static struct net_bridge_mdb_entry *br_multicast_new_group(
 642         struct net_bridge *br, struct net_bridge_port *port,
 643         struct br_ip *group)
 644 {
 645         struct net_bridge_mdb_htable *mdb = br->mdb;
 646         struct net_bridge_mdb_entry *mp;
 647         int hash;
 648
 649         if (!mdb) {
 650                 if (br_mdb_rehash(&br->mdb, BR_HASH_SIZE, 0))
 651                         return NULL;
 652                 goto rehash;
 653         }
 654
 655         hash = br_ip_hash(mdb, group);
 656         mp = br_multicast_get_group(br, port, group, hash);
 657         switch (PTR_ERR(mp)) {
 658         case 0:
 659                 break;
 660
 661         case -EAGAIN:
 662 rehash:
 663                 mdb = br->mdb;
 664                 hash = br_ip_hash(mdb, group);
 665                 break;
 666
 667         default:
 668                 goto out;
 669         }
 670
 671         mp = kzalloc(sizeof(*mp), GFP_ATOMIC);
 672         if (unlikely(!mp))
 673                 goto out;
 674
 675         mp->br = br;
 676         mp->addr = *group;
 677         setup_timer(&mp->timer, br_multicast_group_expired,
 678                     (unsigned long)mp);
 679         setup_timer(&mp->query_timer, br_multicast_group_query_expired,
 680                     (unsigned long)mp);
 681
 682         hlist_add_head_rcu(&mp->hlist[mdb->ver], &mdb->mhash[hash]);
 683         mdb->size++;
 684
 685 out:
 686         return mp;
 687 }
 688
 689 static int br_multicast_add_group(struct net_bridge *br,
 690                                   struct net_bridge_port *port,
 691                                   struct br_ip *group)
 692 {
 693         struct net_bridge_mdb_entry *mp;
 694         struct net_bridge_port_group *p;
 695         struct net_bridge_port_group **pp;
 696         unsigned long now = jiffies;
 697         int err;
 698
 699         spin_lock(&br->multicast_lock);
 700         if (!netif_running(br->dev) ||
 701             (port && port->state == BR_STATE_DISABLED))
 702                 goto out;
 703
 704         mp = br_multicast_new_group(br, port, group);
 705         err = PTR_ERR(mp);
 706         if (unlikely(IS_ERR(mp) || !mp))
 707                 goto err;
 708
 709         if (!port) {
 710                 hlist_add_head(&mp->mglist, &br->mglist);
 711                 mod_timer(&mp->timer, now + br->multicast_membership_interval);
 712                 goto out;
 713         }
 714
 715         for (pp = &mp->ports; (p = *pp); pp = &p->next) {
 716                 if (p->port == port)
 717                         goto found;
 718                 if ((unsigned long)p->port < (unsigned long)port)
 719                         break;
 720         }
 721
 722         p = kzalloc(sizeof(*p), GFP_ATOMIC);
 723         err = -ENOMEM;
 724         if (unlikely(!p))
 725                 goto err;
 726
 727         p->addr = *group;
 728         p->port = port;
 729         p->next = *pp;
 730         hlist_add_head(&p->mglist, &port->mglist);
 731         setup_timer(&p->timer, br_multicast_port_group_expired,
 732                     (unsigned long)p);
 733         setup_timer(&p->query_timer, br_multicast_port_group_query_expired,
 734                     (unsigned long)p);
 735
 736         rcu_assign_pointer(*pp, p);
 737
 738 found:
 739         mod_timer(&p->timer, now + br->multicast_membership_interval);
 740 out:
 741         err = 0;
 742
 743 err:
 744         spin_unlock(&br->multicast_lock);
 745         return err;
 746 }
 747
 748 static int br_ip4_multicast_add_group(struct net_bridge *br,
 749                                       struct net_bridge_port *port,
 750                                       __be32 group)
 751 {
 752         struct br_ip br_group;
 753
 754         if (ipv4_is_local_multicast(group))
 755                 return 0;
 756
 757         br_group.u.ip4 = group;
 758         br_group.proto = htons(ETH_P_IP);
 759
 760         return br_multicast_add_group(br, port, &br_group);
 761 }
 762
 763 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 764 static int br_ip6_multicast_add_group(struct net_bridge *br,
 765                                       struct net_bridge_port *port,
 766                                       const struct in6_addr *group)
 767 {
 768         struct br_ip br_group;
 769
 770         if (ipv6_is_local_multicast(group))
 771                 return 0;
 772
 773         ipv6_addr_copy(&br_group.u.ip6, group);
 774         br_group.proto = htons(ETH_P_IP);
 775
 776         return br_multicast_add_group(br, port, &br_group);
 777 }
 778 #endif
 779
 780 static void br_multicast_router_expired(unsigned long data)
 781 {
 782         struct net_bridge_port *port = (void *)data;
 783         struct net_bridge *br = port->br;
 784
 785         spin_lock(&br->multicast_lock);
 786         if (port->multicast_router != 1 ||
 787             timer_pending(&port->multicast_router_timer) ||
 788             hlist_unhashed(&port->rlist))
 789                 goto out;
 790
 791         hlist_del_init_rcu(&port->rlist);
 792
 793 out:
 794         spin_unlock(&br->multicast_lock);
 795 }
 796
 797 static void br_multicast_local_router_expired(unsigned long data)
 798 {
 799 }
 800
 801 static void __br_multicast_send_query(struct net_bridge *br,
 802                                       struct net_bridge_port *port,
 803                                       struct br_ip *ip)
 804 {
 805         struct sk_buff *skb;
 806
 807         skb = br_multicast_alloc_query(br, ip);
 808         if (!skb)
 809                 return;
 810
 811         if (port) {
 812                 __skb_push(skb, sizeof(struct ethhdr));
 813                 skb->dev = port->dev;
 814                 NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
 815                         dev_queue_xmit);
 816         } else
 817                 netif_rx(skb);
 818 }
 819
 820 static void br_multicast_send_query(struct net_bridge *br,
 821                                     struct net_bridge_port *port, u32 sent)
 822 {
 823         unsigned long time;
 824         struct br_ip br_group;
 825
 826         if (!netif_running(br->dev) || br->multicast_disabled ||
 827             timer_pending(&br->multicast_querier_timer))
 828                 return;
 829
 830         memset(&br_group.u, 0, sizeof(br_group.u));
 831
 832         br_group.proto = htons(ETH_P_IP);
 833         __br_multicast_send_query(br, port, &br_group);
 834
 835 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 836         br_group.proto = htons(ETH_P_IPV6);
 837         __br_multicast_send_query(br, port, &br_group);
 838 #endif
 839
 840         time = jiffies;
 841         time += sent < br->multicast_startup_query_count ?
 842                 br->multicast_startup_query_interval :
 843                 br->multicast_query_interval;
 844         mod_timer(port ? &port->multicast_query_timer :
 845                          &br->multicast_query_timer, time);
 846 }
 847
 848 static void br_multicast_port_query_expired(unsigned long data)
 849 {
 850         struct net_bridge_port *port = (void *)data;
 851         struct net_bridge *br = port->br;
 852
 853         spin_lock(&br->multicast_lock);
 854         if (port->state == BR_STATE_DISABLED ||
 855             port->state == BR_STATE_BLOCKING)
 856                 goto out;
 857
 858         if (port->multicast_startup_queries_sent <
 859             br->multicast_startup_query_count)
 860                 port->multicast_startup_queries_sent++;
 861
 862         br_multicast_send_query(port->br, port,
 863                                 port->multicast_startup_queries_sent);
 864
 865 out:
 866         spin_unlock(&br->multicast_lock);
 867 }
 868
 869 void br_multicast_add_port(struct net_bridge_port *port)
 870 {
 871         port->multicast_router = 1;
 872
 873         setup_timer(&port->multicast_router_timer, br_multicast_router_expired,
 874                     (unsigned long)port);
 875         setup_timer(&port->multicast_query_timer,
 876                     br_multicast_port_query_expired, (unsigned long)port);
 877 }
 878
 879 void br_multicast_del_port(struct net_bridge_port *port)
 880 {
 881         del_timer_sync(&port->multicast_router_timer);
 882 }
 883
 884 static void __br_multicast_enable_port(struct net_bridge_port *port)
 885 {
 886         port->multicast_startup_queries_sent = 0;
 887
 888         if (try_to_del_timer_sync(&port->multicast_query_timer) >= 0 ||
 889             del_timer(&port->multicast_query_timer))
 890                 mod_timer(&port->multicast_query_timer, jiffies);
 891 }
 892
 893 void br_multicast_enable_port(struct net_bridge_port *port)
 894 {
 895         struct net_bridge *br = port->br;
 896
 897         spin_lock(&br->multicast_lock);
 898         if (br->multicast_disabled || !netif_running(br->dev))
 899                 goto out;
 900
 901         __br_multicast_enable_port(port);
 902
 903 out:
 904         spin_unlock(&br->multicast_lock);
 905 }
 906
 907 void br_multicast_disable_port(struct net_bridge_port *port)
 908 {
 909         struct net_bridge *br = port->br;
 910         struct net_bridge_port_group *pg;
 911         struct hlist_node *p, *n;
 912
 913         spin_lock(&br->multicast_lock);
 914         hlist_for_each_entry_safe(pg, p, n, &port->mglist, mglist)
 915                 br_multicast_del_pg(br, pg);
 916
 917         if (!hlist_unhashed(&port->rlist))
 918                 hlist_del_init_rcu(&port->rlist);
 919         del_timer(&port->multicast_router_timer);
 920         del_timer(&port->multicast_query_timer);
 921         spin_unlock(&br->multicast_lock);
 922 }
 923
 924 static int br_ip4_multicast_igmp3_report(struct net_bridge *br,
 925                                          struct net_bridge_port *port,
 926                                          struct sk_buff *skb)
 927 {
 928         struct igmpv3_report *ih;
 929         struct igmpv3_grec *grec;
 930         int i;
 931         int len;
 932         int num;
 933         int type;
 934         int err = 0;
 935         __be32 group;
 936
 937         if (!pskb_may_pull(skb, sizeof(*ih)))
 938                 return -EINVAL;
 939
 940         ih = igmpv3_report_hdr(skb);
 941         num = ntohs(ih->ngrec);
 942         len = sizeof(*ih);
 943
 944         for (i = 0; i < num; i++) {
 945                 len += sizeof(*grec);
 946                 if (!pskb_may_pull(skb, len))
 947                         return -EINVAL;
 948
 949                 grec = (void *)(skb->data + len - sizeof(*grec));
 950                 group = grec->grec_mca;
 951                 type = grec->grec_type;
 952
 953                 len += ntohs(grec->grec_nsrcs) * 4;
 954                 if (!pskb_may_pull(skb, len))
 955                         return -EINVAL;
 956
 957                 /* We treat this as an IGMPv2 report for now. */
 958                 switch (type) {
 959                 case IGMPV3_MODE_IS_INCLUDE:
 960                 case IGMPV3_MODE_IS_EXCLUDE:
 961                 case IGMPV3_CHANGE_TO_INCLUDE:
 962                 case IGMPV3_CHANGE_TO_EXCLUDE:
 963                 case IGMPV3_ALLOW_NEW_SOURCES:
 964                 case IGMPV3_BLOCK_OLD_SOURCES:
 965                         break;
 966
 967                 default:
 968                         continue;
 969                 }
 970
 971                 err = br_ip4_multicast_add_group(br, port, group);
 972                 if (err)
 973                         break;
 974         }
 975
 976         return err;
 977 }
 978
 979 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 980 static int br_ip6_multicast_mld2_report(struct net_bridge *br,
 981                                         struct net_bridge_port *port,
 982                                         struct sk_buff *skb)
 983 {
 984         struct icmp6hdr *icmp6h;
 985         struct mld2_grec *grec;
 986         int i;
 987         int len;
 988         int num;
 989         int err = 0;
 990
 991         if (!pskb_may_pull(skb, sizeof(*icmp6h)))
 992                 return -EINVAL;
 993
 994         icmp6h = icmp6_hdr(skb);
 995         num = ntohs(icmp6h->icmp6_dataun.un_data16[1]);
 996         len = sizeof(*icmp6h);
 997
 998         for (i = 0; i < num; i++) {
 999                 __be16 *nsrcs, _nsrcs;
1000
1001                 nsrcs = skb_header_pointer(skb,
1002                                            len + offsetof(struct mld2_grec,
1003                                                           grec_mca),
1004                                            sizeof(_nsrcs), &_nsrcs);
1005                 if (!nsrcs)
1006                         return -EINVAL;
1007
1008                 if (!pskb_may_pull(skb,
1009                                    len + sizeof(*grec) +
1010                                    sizeof(struct in6_addr) * (*nsrcs)))
1011                         return -EINVAL;
1012
1013                 grec = (struct mld2_grec *)(skb->data + len);
1014                 len += sizeof(*grec) + sizeof(struct in6_addr) * (*nsrcs);
1015
1016                 /* We treat these as MLDv1 reports for now. */
1017                 switch (grec->grec_type) {
1018                 case MLD2_MODE_IS_INCLUDE:
1019                 case MLD2_MODE_IS_EXCLUDE:
1020                 case MLD2_CHANGE_TO_INCLUDE:
1021                 case MLD2_CHANGE_TO_EXCLUDE:
1022                 case MLD2_ALLOW_NEW_SOURCES:
1023                 case MLD2_BLOCK_OLD_SOURCES:
1024                         break;
1025
1026                 default:
1027                         continue;
1028                 }
1029
1030                 err = br_ip6_multicast_add_group(br, port, &grec->grec_mca);
1031                 if (!err)
1032                         break;
1033         }
1034
1035         return err;
1036 }
1037 #endif
1038
1039 /*
1040  * Add port to rotuer_list
1041  *  list is maintained ordered by pointer value
1042  *  and locked by br->multicast_lock and RCU
1043  */
1044 static void br_multicast_add_router(struct net_bridge *br,
1045                                     struct net_bridge_port *port)
1046 {
1047         struct net_bridge_port *p;
1048         struct hlist_node *n, *slot = NULL;
1049
1050         hlist_for_each_entry(p, n, &br->router_list, rlist) {
1051                 if ((unsigned long) port >= (unsigned long) p)
1052                         break;
1053                 slot = n;
1054         }
1055
1056         if (slot)
1057                 hlist_add_after_rcu(slot, &port->rlist);
1058         else
1059                 hlist_add_head_rcu(&port->rlist, &br->router_list);
1060 }
1061
1062 static void br_multicast_mark_router(struct net_bridge *br,
1063                                      struct net_bridge_port *port)
1064 {
1065         unsigned long now = jiffies;
1066
1067         if (!port) {
1068                 if (br->multicast_router == 1)
1069                         mod_timer(&br->multicast_router_timer,
1070                                   now + br->multicast_querier_interval);
1071                 return;
1072         }
1073
1074         if (port->multicast_router != 1)
1075                 return;
1076
1077         if (!hlist_unhashed(&port->rlist))
1078                 goto timer;
1079
1080         br_multicast_add_router(br, port);
1081
1082 timer:
1083         mod_timer(&port->multicast_router_timer,
1084                   now + br->multicast_querier_interval);
1085 }
1086
1087 static void br_multicast_query_received(struct net_bridge *br,
1088                                         struct net_bridge_port *port,
1089                                         int saddr)
1090 {
1091         if (saddr)
1092                 mod_timer(&br->multicast_querier_timer,
1093                           jiffies + br->multicast_querier_interval);
1094         else if (timer_pending(&br->multicast_querier_timer))
1095                 return;
1096
1097         br_multicast_mark_router(br, port);
1098 }
1099
1100 static int br_ip4_multicast_query(struct net_bridge *br,
1101                                   struct net_bridge_port *port,
1102                                   struct sk_buff *skb)
1103 {
1104         struct iphdr *iph = ip_hdr(skb);
1105         struct igmphdr *ih = igmp_hdr(skb);
1106         struct net_bridge_mdb_entry *mp;
1107         struct igmpv3_query *ih3;
1108         struct net_bridge_port_group *p;
1109         struct net_bridge_port_group **pp;
1110         unsigned long max_delay;
1111         unsigned long now = jiffies;
1112         __be32 group;
1113         int err = 0;
1114
1115         spin_lock(&br->multicast_lock);
1116         if (!netif_running(br->dev) ||
1117             (port && port->state == BR_STATE_DISABLED))
1118                 goto out;
1119
1120         br_multicast_query_received(br, port, !!iph->saddr);
1121
1122         group = ih->group;
1123
1124         if (skb->len == sizeof(*ih)) {
1125                 max_delay = ih->code * (HZ / IGMP_TIMER_SCALE);
1126
1127                 if (!max_delay) {
1128                         max_delay = 10 * HZ;
1129                         group = 0;
1130                 }
1131         } else {
1132                 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query))) {
1133                         err = -EINVAL;
1134                         goto out;
1135                 }
1136
1137                 ih3 = igmpv3_query_hdr(skb);
1138                 if (ih3->nsrcs)
1139                         goto out;
1140
1141                 max_delay = ih3->code ?
1142                             IGMPV3_MRC(ih3->code) * (HZ / IGMP_TIMER_SCALE) : 1;
1143         }
1144
1145         if (!group)
1146                 goto out;
1147
1148         mp = br_mdb_ip4_get(br->mdb, group);
1149         if (!mp)
1150                 goto out;
1151
1152         max_delay *= br->multicast_last_member_count;
1153
1154         if (!hlist_unhashed(&mp->mglist) &&
1155             (timer_pending(&mp->timer) ?
1156              time_after(mp->timer.expires, now + max_delay) :
1157              try_to_del_timer_sync(&mp->timer) >= 0))
1158                 mod_timer(&mp->timer, now + max_delay);
1159
1160         for (pp = &mp->ports; (p = *pp); pp = &p->next) {
1161                 if (timer_pending(&p->timer) ?
1162                     time_after(p->timer.expires, now + max_delay) :
1163                     try_to_del_timer_sync(&p->timer) >= 0)
1164                         mod_timer(&mp->timer, now + max_delay);
1165         }
1166
1167 out:
1168         spin_unlock(&br->multicast_lock);
1169         return err;
1170 }
1171
1172 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1173 static int br_ip6_multicast_query(struct net_bridge *br,
1174                                   struct net_bridge_port *port,
1175                                   struct sk_buff *skb)
1176 {
1177         struct ipv6hdr *ip6h = ipv6_hdr(skb);
1178         struct mld_msg *mld = (struct mld_msg *) icmp6_hdr(skb);
1179         struct net_bridge_mdb_entry *mp;
1180         struct mld2_query *mld2q;
1181         struct net_bridge_port_group *p, **pp;
1182         unsigned long max_delay;
1183         unsigned long now = jiffies;
1184         struct in6_addr *group = NULL;
1185         int err = 0;
1186
1187         spin_lock(&br->multicast_lock);
1188         if (!netif_running(br->dev) ||
1189             (port && port->state == BR_STATE_DISABLED))
1190                 goto out;
1191
1192         br_multicast_query_received(br, port, !ipv6_addr_any(&ip6h->saddr));
1193
1194         if (skb->len == sizeof(*mld)) {
1195                 if (!pskb_may_pull(skb, sizeof(*mld))) {
1196                         err = -EINVAL;
1197                         goto out;
1198                 }
1199                 mld = (struct mld_msg *) icmp6_hdr(skb);
1200                 max_delay = msecs_to_jiffies(htons(mld->mld_maxdelay));
1201                 if (max_delay)
1202                         group = &mld->mld_mca;
1203         } else if (skb->len >= sizeof(*mld2q)) {
1204                 if (!pskb_may_pull(skb, sizeof(*mld2q))) {
1205                         err = -EINVAL;
1206                         goto out;
1207                 }
1208                 mld2q = (struct mld2_query *)icmp6_hdr(skb);
1209                 if (!mld2q->mld2q_nsrcs)
1210                         group = &mld2q->mld2q_mca;
1211                 max_delay = mld2q->mld2q_mrc ? MLDV2_MRC(mld2q->mld2q_mrc) : 1;
1212         }
1213
1214         if (!group)
1215                 goto out;
1216
1217         mp = br_mdb_ip6_get(br->mdb, group);
1218         if (!mp)
1219                 goto out;
1220
1221         max_delay *= br->multicast_last_member_count;
1222         if (!hlist_unhashed(&mp->mglist) &&
1223             (timer_pending(&mp->timer) ?
1224              time_after(mp->timer.expires, now + max_delay) :
1225              try_to_del_timer_sync(&mp->timer) >= 0))
1226                 mod_timer(&mp->timer, now + max_delay);
1227
1228         for (pp = &mp->ports; (p = *pp); pp = &p->next) {
1229                 if (timer_pending(&p->timer) ?
1230                     time_after(p->timer.expires, now + max_delay) :
1231                     try_to_del_timer_sync(&p->timer) >= 0)
1232                         mod_timer(&mp->timer, now + max_delay);
1233         }
1234
1235 out:
1236         spin_unlock(&br->multicast_lock);
1237         return err;
1238 }
1239 #endif
1240
1241 static void br_multicast_leave_group(struct net_bridge *br,
1242                                      struct net_bridge_port *port,
1243                                      struct br_ip *group)
1244 {
1245         struct net_bridge_mdb_htable *mdb;
1246         struct net_bridge_mdb_entry *mp;
1247         struct net_bridge_port_group *p;
1248         unsigned long now;
1249         unsigned long time;
1250
1251         spin_lock(&br->multicast_lock);
1252         if (!netif_running(br->dev) ||
1253             (port && port->state == BR_STATE_DISABLED) ||
1254             timer_pending(&br->multicast_querier_timer))
1255                 goto out;
1256
1257         mdb = br->mdb;
1258         mp = br_mdb_ip_get(mdb, group);
1259         if (!mp)
1260                 goto out;
1261
1262         now = jiffies;
1263         time = now + br->multicast_last_member_count *
1264                      br->multicast_last_member_interval;
1265
1266         if (!port) {
1267                 if (!hlist_unhashed(&mp->mglist) &&
1268                     (timer_pending(&mp->timer) ?
1269                      time_after(mp->timer.expires, time) :
1270                      try_to_del_timer_sync(&mp->timer) >= 0)) {
1271                         mod_timer(&mp->timer, time);
1272
1273                         mp->queries_sent = 0;
1274                         mod_timer(&mp->query_timer, now);
1275                 }
1276
1277                 goto out;
1278         }
1279
1280         for (p = mp->ports; p; p = p->next) {
1281                 if (p->port != port)
1282                         continue;
1283
1284                 if (!hlist_unhashed(&p->mglist) &&
1285                     (timer_pending(&p->timer) ?
1286                      time_after(p->timer.expires, time) :
1287                      try_to_del_timer_sync(&p->timer) >= 0)) {
1288                         mod_timer(&p->timer, time);
1289
1290                         p->queries_sent = 0;
1291                         mod_timer(&p->query_timer, now);
1292                 }
1293
1294                 break;
1295         }
1296
1297 out:
1298         spin_unlock(&br->multicast_lock);
1299 }
1300
1301 static void br_ip4_multicast_leave_group(struct net_bridge *br,
1302                                          struct net_bridge_port *port,
1303                                          __be32 group)
1304 {
1305         struct br_ip br_group;
1306
1307         if (ipv4_is_local_multicast(group))
1308                 return;
1309
1310         br_group.u.ip4 = group;
1311         br_group.proto = htons(ETH_P_IP);
1312
1313         br_multicast_leave_group(br, port, &br_group);
1314 }
1315
1316 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1317 static void br_ip6_multicast_leave_group(struct net_bridge *br,
1318                                          struct net_bridge_port *port,
1319                                          const struct in6_addr *group)
1320 {
1321         struct br_ip br_group;
1322
1323         if (ipv6_is_local_multicast(group))
1324                 return;
1325
1326         ipv6_addr_copy(&br_group.u.ip6, group);
1327         br_group.proto = htons(ETH_P_IPV6);
1328
1329         br_multicast_leave_group(br, port, &br_group);
1330 }
1331 #endif
1332
1333 static int br_multicast_ipv4_rcv(struct net_bridge *br,
1334                                  struct net_bridge_port *port,
1335                                  struct sk_buff *skb)
1336 {
1337         struct sk_buff *skb2 = skb;
1338         struct iphdr *iph;
1339         struct igmphdr *ih;
1340         unsigned len;
1341         unsigned offset;
1342         int err;
1343
1344         /* We treat OOM as packet loss for now. */
1345         if (!pskb_may_pull(skb, sizeof(*iph)))
1346                 return -EINVAL;
1347
1348         iph = ip_hdr(skb);
1349
1350         if (iph->ihl < 5 || iph->version != 4)
1351                 return -EINVAL;
1352
1353         if (!pskb_may_pull(skb, ip_hdrlen(skb)))
1354                 return -EINVAL;
1355
1356         iph = ip_hdr(skb);
1357
1358         if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1359                 return -EINVAL;
1360
1361         if (iph->protocol != IPPROTO_IGMP)
1362                 return 0;
1363
1364         len = ntohs(iph->tot_len);
1365         if (skb->len < len || len < ip_hdrlen(skb))
1366                 return -EINVAL;
1367
1368         if (skb->len > len) {
1369                 skb2 = skb_clone(skb, GFP_ATOMIC);
1370                 if (!skb2)
1371                         return -ENOMEM;
1372
1373                 err = pskb_trim_rcsum(skb2, len);
1374                 if (err)
1375                         goto err_out;
1376         }
1377
1378         len -= ip_hdrlen(skb2);
1379         offset = skb_network_offset(skb2) + ip_hdrlen(skb2);
1380         __skb_pull(skb2, offset);
1381         skb_reset_transport_header(skb2);
1382
1383         err = -EINVAL;
1384         if (!pskb_may_pull(skb2, sizeof(*ih)))
1385                 goto out;
1386
1387         switch (skb2->ip_summed) {
1388         case CHECKSUM_COMPLETE:
1389                 if (!csum_fold(skb2->csum))
1390                         break;
1391                 /* fall through */
1392         case CHECKSUM_NONE:
1393                 skb2->csum = 0;
1394                 if (skb_checksum_complete(skb2))
1395                         goto out;
1396         }
1397
1398         err = 0;
1399
1400         BR_INPUT_SKB_CB(skb)->igmp = 1;
1401         ih = igmp_hdr(skb2);
1402
1403         switch (ih->type) {
1404         case IGMP_HOST_MEMBERSHIP_REPORT:
1405         case IGMPV2_HOST_MEMBERSHIP_REPORT:
1406                 BR_INPUT_SKB_CB(skb2)->mrouters_only = 1;
1407                 err = br_ip4_multicast_add_group(br, port, ih->group);
1408                 break;
1409         case IGMPV3_HOST_MEMBERSHIP_REPORT:
1410                 err = br_ip4_multicast_igmp3_report(br, port, skb2);
1411                 break;
1412         case IGMP_HOST_MEMBERSHIP_QUERY:
1413                 err = br_ip4_multicast_query(br, port, skb2);
1414                 break;
1415         case IGMP_HOST_LEAVE_MESSAGE:
1416                 br_ip4_multicast_leave_group(br, port, ih->group);
1417                 break;
1418         }
1419
1420 out:
1421         __skb_push(skb2, offset);
1422 err_out:
1423         if (skb2 != skb)
1424                 kfree_skb(skb2);
1425         return err;
1426 }
1427
1428 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1429 static int br_multicast_ipv6_rcv(struct net_bridge *br,
1430                                  struct net_bridge_port *port,
1431                                  struct sk_buff *skb)
1432 {
1433         struct sk_buff *skb2 = skb;
1434         struct ipv6hdr *ip6h;
1435         struct icmp6hdr *icmp6h;
1436         u8 nexthdr;
1437         unsigned len;
1438         int offset;
1439         int err;
1440
1441         if (!pskb_may_pull(skb, sizeof(*ip6h)))
1442                 return -EINVAL;
1443
1444         ip6h = ipv6_hdr(skb);
1445
1446         /*
1447          * We're interested in MLD messages only.
1448          *  - Version is 6
1449          *  - MLD has always Router Alert hop-by-hop option
1450          *  - But we do not support jumbrograms.
1451          */
1452         if (ip6h->version != 6 ||
1453             ip6h->nexthdr != IPPROTO_HOPOPTS ||
1454             ip6h->payload_len == 0)
1455                 return 0;
1456
1457         len = ntohs(ip6h->payload_len);
1458         if (skb->len < len)
1459                 return -EINVAL;
1460
1461         nexthdr = ip6h->nexthdr;
1462         offset = ipv6_skip_exthdr(skb, sizeof(*ip6h), &nexthdr);
1463
1464         if (offset < 0 || nexthdr != IPPROTO_ICMPV6)
1465                 return 0;
1466
1467         /* Okay, we found ICMPv6 header */
1468         skb2 = skb_clone(skb, GFP_ATOMIC);
1469         if (!skb2)
1470                 return -ENOMEM;
1471
1472         len -= offset - skb_network_offset(skb2);
1473
1474         __skb_pull(skb2, offset);
1475         skb_reset_transport_header(skb2);
1476
1477         err = -EINVAL;
1478         if (!pskb_may_pull(skb2, sizeof(*icmp6h)))
1479                 goto out;
1480
1481         icmp6h = icmp6_hdr(skb2);
1482
1483         switch (icmp6h->icmp6_type) {
1484         case ICMPV6_MGM_QUERY:
1485         case ICMPV6_MGM_REPORT:
1486         case ICMPV6_MGM_REDUCTION:
1487         case ICMPV6_MLD2_REPORT:
1488                 break;
1489         default:
1490                 err = 0;
1491                 goto out;
1492         }
1493
1494         /* Okay, we found MLD message. Check further. */
1495         if (skb2->len > len) {
1496                 err = pskb_trim_rcsum(skb2, len);
1497                 if (err)
1498                         goto out;
1499         }
1500
1501         switch (skb2->ip_summed) {
1502         case CHECKSUM_COMPLETE:
1503                 if (!csum_fold(skb2->csum))
1504                         break;
1505                 /*FALLTHROUGH*/
1506         case CHECKSUM_NONE:
1507                 skb2->csum = 0;
1508                 if (skb_checksum_complete(skb2))
1509                         goto out;
1510         }
1511
1512         err = 0;
1513
1514         BR_INPUT_SKB_CB(skb)->igmp = 1;
1515
1516         switch (icmp6h->icmp6_type) {
1517         case ICMPV6_MGM_REPORT:
1518             {
1519                 struct mld_msg *mld = (struct mld_msg *)icmp6h;
1520                 BR_INPUT_SKB_CB(skb2)->mrouters_only = 1;
1521                 err = br_ip6_multicast_add_group(br, port, &mld->mld_mca);
1522                 break;
1523             }
1524         case ICMPV6_MLD2_REPORT:
1525                 err = br_ip6_multicast_mld2_report(br, port, skb2);
1526                 break;
1527         case ICMPV6_MGM_QUERY:
1528                 err = br_ip6_multicast_query(br, port, skb2);
1529                 break;
1530         case ICMPV6_MGM_REDUCTION:
1531             {
1532                 struct mld_msg *mld = (struct mld_msg *)icmp6h;
1533                 br_ip6_multicast_leave_group(br, port, &mld->mld_mca);
1534             }
1535         }
1536
1537 out:
1538         __skb_push(skb2, offset);
1539         if (skb2 != skb)
1540                 kfree_skb(skb2);
1541         return err;
1542 }
1543 #endif
1544
1545 int br_multicast_rcv(struct net_bridge *br, struct net_bridge_port *port,
1546                      struct sk_buff *skb)
1547 {
1548         BR_INPUT_SKB_CB(skb)->igmp = 0;
1549         BR_INPUT_SKB_CB(skb)->mrouters_only = 0;
1550
1551         if (br->multicast_disabled)
1552                 return 0;
1553
1554         switch (skb->protocol) {
1555         case htons(ETH_P_IP):
1556                 return br_multicast_ipv4_rcv(br, port, skb);
1557 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
1558         case htons(ETH_P_IPV6):
1559                 return br_multicast_ipv6_rcv(br, port, skb);
1560 #endif
1561         }
1562
1563         return 0;
1564 }
1565
1566 static void br_multicast_query_expired(unsigned long data)
1567 {
1568         struct net_bridge *br = (void *)data;
1569
1570         spin_lock(&br->multicast_lock);
1571         if (br->multicast_startup_queries_sent <
1572             br->multicast_startup_query_count)
1573                 br->multicast_startup_queries_sent++;
1574
1575         br_multicast_send_query(br, NULL, br->multicast_startup_queries_sent);
1576
1577         spin_unlock(&br->multicast_lock);
1578 }
1579
1580 void br_multicast_init(struct net_bridge *br)
1581 {
1582         br->hash_elasticity = 4;
1583         br->hash_max = 512;
1584
1585         br->multicast_router = 1;
1586         br->multicast_last_member_count = 2;
1587         br->multicast_startup_query_count = 2;
1588
1589         br->multicast_last_member_interval = HZ;
1590         br->multicast_query_response_interval = 10 * HZ;
1591         br->multicast_startup_query_interval = 125 * HZ / 4;
1592         br->multicast_query_interval = 125 * HZ;
1593         br->multicast_querier_interval = 255 * HZ;
1594         br->multicast_membership_interval = 260 * HZ;
1595
1596         spin_lock_init(&br->multicast_lock);
1597         setup_timer(&br->multicast_router_timer,
1598                     br_multicast_local_router_expired, 0);
1599         setup_timer(&br->multicast_querier_timer,
1600                     br_multicast_local_router_expired, 0);
1601         setup_timer(&br->multicast_query_timer, br_multicast_query_expired,
1602                     (unsigned long)br);
1603 }
1604
1605 void br_multicast_open(struct net_bridge *br)
1606 {
1607         br->multicast_startup_queries_sent = 0;
1608
1609         if (br->multicast_disabled)
1610                 return;
1611
1612         mod_timer(&br->multicast_query_timer, jiffies);
1613 }
1614
1615 void br_multicast_stop(struct net_bridge *br)
1616 {
1617         struct net_bridge_mdb_htable *mdb;
1618         struct net_bridge_mdb_entry *mp;
1619         struct hlist_node *p, *n;
1620         u32 ver;
1621         int i;
1622
1623         del_timer_sync(&br->multicast_router_timer);
1624         del_timer_sync(&br->multicast_querier_timer);
1625         del_timer_sync(&br->multicast_query_timer);
1626
1627         spin_lock_bh(&br->multicast_lock);
1628         mdb = br->mdb;
1629         if (!mdb)
1630                 goto out;
1631
1632         br->mdb = NULL;
1633
1634         ver = mdb->ver;
1635         for (i = 0; i < mdb->max; i++) {
1636                 hlist_for_each_entry_safe(mp, p, n, &mdb->mhash[i],
1637                                           hlist[ver]) {
1638                         del_timer(&mp->timer);
1639                         del_timer(&mp->query_timer);
1640                         call_rcu_bh(&mp->rcu, br_multicast_free_group);
1641                 }
1642         }
1643
1644         if (mdb->old) {
1645                 spin_unlock_bh(&br->multicast_lock);
1646                 rcu_barrier_bh();
1647                 spin_lock_bh(&br->multicast_lock);
1648                 WARN_ON(mdb->old);
1649         }
1650
1651         mdb->old = mdb;
1652         call_rcu_bh(&mdb->rcu, br_mdb_free);
1653
1654 out:
1655         spin_unlock_bh(&br->multicast_lock);
1656 }
1657
1658 int br_multicast_set_router(struct net_bridge *br, unsigned long val)
1659 {
1660         int err = -ENOENT;
1661
1662         spin_lock_bh(&br->multicast_lock);
1663         if (!netif_running(br->dev))
1664                 goto unlock;
1665
1666         switch (val) {
1667         case 0:
1668         case 2:
1669                 del_timer(&br->multicast_router_timer);
1670                 /* fall through */
1671         case 1:
1672                 br->multicast_router = val;
1673                 err = 0;
1674                 break;
1675
1676         default:
1677                 err = -EINVAL;
1678                 break;
1679         }
1680
1681 unlock:
1682         spin_unlock_bh(&br->multicast_lock);
1683
1684         return err;
1685 }
1686
1687 int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
1688 {
1689         struct net_bridge *br = p->br;
1690         int err = -ENOENT;
1691
1692         spin_lock(&br->multicast_lock);
1693         if (!netif_running(br->dev) || p->state == BR_STATE_DISABLED)
1694                 goto unlock;
1695
1696         switch (val) {
1697         case 0:
1698         case 1:
1699         case 2:
1700                 p->multicast_router = val;
1701                 err = 0;
1702
1703                 if (val < 2 && !hlist_unhashed(&p->rlist))
1704                         hlist_del_init_rcu(&p->rlist);
1705
1706                 if (val == 1)
1707                         break;
1708
1709                 del_timer(&p->multicast_router_timer);
1710
1711                 if (val == 0)
1712                         break;
1713
1714                 br_multicast_add_router(br, p);
1715                 break;
1716
1717         default:
1718                 err = -EINVAL;
1719                 break;
1720         }
1721
1722 unlock:
1723         spin_unlock(&br->multicast_lock);
1724
1725         return err;
1726 }
1727
1728 int br_multicast_toggle(struct net_bridge *br, unsigned long val)
1729 {
1730         struct net_bridge_port *port;
1731         int err = -ENOENT;
1732
1733         spin_lock(&br->multicast_lock);
1734         if (!netif_running(br->dev))
1735                 goto unlock;
1736
1737         err = 0;
1738         if (br->multicast_disabled == !val)
1739                 goto unlock;
1740
1741         br->multicast_disabled = !val;
1742         if (br->multicast_disabled)
1743                 goto unlock;
1744
1745         if (br->mdb) {
1746                 if (br->mdb->old) {
1747                         err = -EEXIST;
1748 rollback:
1749                         br->multicast_disabled = !!val;
1750                         goto unlock;
1751                 }
1752
1753                 err = br_mdb_rehash(&br->mdb, br->mdb->max,
1754                                     br->hash_elasticity);
1755                 if (err)
1756                         goto rollback;
1757         }
1758
1759         br_multicast_open(br);
1760         list_for_each_entry(port, &br->port_list, list) {
1761                 if (port->state == BR_STATE_DISABLED ||
1762                     port->state == BR_STATE_BLOCKING)
1763                         continue;
1764
1765                 __br_multicast_enable_port(port);
1766         }
1767
1768 unlock:
1769         spin_unlock(&br->multicast_lock);
1770
1771         return err;
1772 }
1773
1774 int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val)
1775 {
1776         int err = -ENOENT;
1777         u32 old;
1778
1779         spin_lock(&br->multicast_lock);
1780         if (!netif_running(br->dev))
1781                 goto unlock;
1782
1783         err = -EINVAL;
1784         if (!is_power_of_2(val))
1785                 goto unlock;
1786         if (br->mdb && val < br->mdb->size)
1787                 goto unlock;
1788
1789         err = 0;
1790
1791         old = br->hash_max;
1792         br->hash_max = val;
1793
1794         if (br->mdb) {
1795                 if (br->mdb->old) {
1796                         err = -EEXIST;
1797 rollback:
1798                         br->hash_max = old;
1799                         goto unlock;
1800                 }
1801
1802                 err = br_mdb_rehash(&br->mdb, br->hash_max,
1803                                     br->hash_elasticity);
1804                 if (err)
1805                         goto rollback;
1806         }
1807
1808 unlock:
1809         spin_unlock(&br->multicast_lock);
1810
1811         return err;
1812 }