Pileus Git - ~andy/linux/blob - 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 IS_ENABLED(CONFIG_IPV6)
  28 #include <net/ipv6.h>
  29 #include <net/mld.h>
  30 #include <net/ip6_checksum.h>
  31 #endif
  32
  33 #include "br_private.h"
  34
  35 static void br_multicast_start_querier(struct net_bridge *br);
  36 unsigned int br_mdb_rehash_seq;
  37
  38 static inline int br_ip_equal(const struct br_ip *a, const struct br_ip *b)
  39 {
  40         if (a->proto != b->proto)
  41                 return 0;
  42         switch (a->proto) {
  43         case htons(ETH_P_IP):
  44                 return a->u.ip4 == b->u.ip4;
  45 #if IS_ENABLED(CONFIG_IPV6)
  46         case htons(ETH_P_IPV6):
  47                 return ipv6_addr_equal(&a->u.ip6, &b->u.ip6);
  48 #endif
  49         }
  50         return 0;
  51 }
  52
  53 static inline int __br_ip4_hash(struct net_bridge_mdb_htable *mdb, __be32 ip)
  54 {
  55         return jhash_1word(mdb->secret, (__force u32)ip) & (mdb->max - 1);
  56 }
  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 {
  62         return jhash2((__force u32 *)ip->s6_addr32, 4, mdb->secret) & (mdb->max - 1);
  63 }
  64 #endif
  65
  66 static inline int br_ip_hash(struct net_bridge_mdb_htable *mdb,
  67                              struct br_ip *ip)
  68 {
  69         switch (ip->proto) {
  70         case htons(ETH_P_IP):
  71                 return __br_ip4_hash(mdb, ip->u.ip4);
  72 #if IS_ENABLED(CONFIG_IPV6)
  73         case htons(ETH_P_IPV6):
  74                 return __br_ip6_hash(mdb, &ip->u.ip6);
  75 #endif
  76         }
  77         return 0;
  78 }
  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         struct hlist_node *p;
  85
  86         hlist_for_each_entry_rcu(mp, p, &mdb->mhash[hash], hlist[mdb->ver]) {
  87                 if (br_ip_equal(&mp->addr, dst))
  88                         return mp;
  89         }
  90
  91         return NULL;
  92 }
  93
  94 struct net_bridge_mdb_entry *br_mdb_ip_get(struct net_bridge_mdb_htable *mdb,
  95                                            struct br_ip *dst)
  96 {
  97         if (!mdb)
  98                 return NULL;
  99
 100         return __br_mdb_ip_get(mdb, dst, br_ip_hash(mdb, dst));
 101 }
 102
 103 static struct net_bridge_mdb_entry *br_mdb_ip4_get(
 104         struct net_bridge_mdb_htable *mdb, __be32 dst)
 105 {
 106         struct br_ip br_dst;
 107
 108         br_dst.u.ip4 = dst;
 109         br_dst.proto = htons(ETH_P_IP);
 110
 111         return br_mdb_ip_get(mdb, &br_dst);
 112 }
 113
 114 #if IS_ENABLED(CONFIG_IPV6)
 115 static struct net_bridge_mdb_entry *br_mdb_ip6_get(
 116         struct net_bridge_mdb_htable *mdb, const struct in6_addr *dst)
 117 {
 118         struct br_ip br_dst;
 119
 120         br_dst.u.ip6 = *dst;
 121         br_dst.proto = htons(ETH_P_IPV6);
 122
 123         return br_mdb_ip_get(mdb, &br_dst);
 124 }
 125 #endif
 126
 127 struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br,
 128                                         struct sk_buff *skb)
 129 {
 130         struct net_bridge_mdb_htable *mdb = rcu_dereference(br->mdb);
 131         struct br_ip ip;
 132
 133         if (br->multicast_disabled)
 134                 return NULL;
 135
 136         if (BR_INPUT_SKB_CB(skb)->igmp)
 137                 return NULL;
 138
 139         ip.proto = skb->protocol;
 140
 141         switch (skb->protocol) {
 142         case htons(ETH_P_IP):
 143                 ip.u.ip4 = ip_hdr(skb)->daddr;
 144                 break;
 145 #if IS_ENABLED(CONFIG_IPV6)
 146         case htons(ETH_P_IPV6):
 147                 ip.u.ip6 = ipv6_hdr(skb)->daddr;
 148                 break;
 149 #endif
 150         default:
 151                 return NULL;
 152         }
 153
 154         return br_mdb_ip_get(mdb, &ip);
 155 }
 156
 157 static void br_mdb_free(struct rcu_head *head)
 158 {
 159         struct net_bridge_mdb_htable *mdb =
 160                 container_of(head, struct net_bridge_mdb_htable, rcu);
 161         struct net_bridge_mdb_htable *old = mdb->old;
 162
 163         mdb->old = NULL;
 164         kfree(old->mhash);
 165         kfree(old);
 166 }
 167
 168 static int br_mdb_copy(struct net_bridge_mdb_htable *new,
 169                        struct net_bridge_mdb_htable *old,
 170                        int elasticity)
 171 {
 172         struct net_bridge_mdb_entry *mp;
 173         struct hlist_node *p;
 174         int maxlen;
 175         int len;
 176         int i;
 177
 178         for (i = 0; i < old->max; i++)
 179                 hlist_for_each_entry(mp, p, &old->mhash[i], hlist[old->ver])
 180                         hlist_add_head(&mp->hlist[new->ver],
 181                                        &new->mhash[br_ip_hash(new, &mp->addr)]);
 182
 183         if (!elasticity)
 184                 return 0;
 185
 186         maxlen = 0;
 187         for (i = 0; i < new->max; i++) {
 188                 len = 0;
 189                 hlist_for_each_entry(mp, p, &new->mhash[i], hlist[new->ver])
 190                         len++;
 191                 if (len > maxlen)
 192                         maxlen = len;
 193         }
 194
 195         return maxlen > elasticity ? -EINVAL : 0;
 196 }
 197
 198 void br_multicast_free_pg(struct rcu_head *head)
 199 {
 200         struct net_bridge_port_group *p =
 201                 container_of(head, struct net_bridge_port_group, rcu);
 202
 203         kfree(p);
 204 }
 205
 206 static void br_multicast_free_group(struct rcu_head *head)
 207 {
 208         struct net_bridge_mdb_entry *mp =
 209                 container_of(head, struct net_bridge_mdb_entry, rcu);
 210
 211         kfree(mp);
 212 }
 213
 214 static void br_multicast_group_expired(unsigned long data)
 215 {
 216         struct net_bridge_mdb_entry *mp = (void *)data;
 217         struct net_bridge *br = mp->br;
 218         struct net_bridge_mdb_htable *mdb;
 219
 220         spin_lock(&br->multicast_lock);
 221         if (!netif_running(br->dev) || timer_pending(&mp->timer))
 222                 goto out;
 223
 224         mp->mglist = false;
 225
 226         if (mp->ports)
 227                 goto out;
 228
 229         mdb = mlock_dereference(br->mdb, br);
 230
 231         hlist_del_rcu(&mp->hlist[mdb->ver]);
 232         mdb->size--;
 233
 234         call_rcu_bh(&mp->rcu, br_multicast_free_group);
 235
 236 out:
 237         spin_unlock(&br->multicast_lock);
 238 }
 239
 240 static void br_multicast_del_pg(struct net_bridge *br,
 241                                 struct net_bridge_port_group *pg)
 242 {
 243         struct net_bridge_mdb_htable *mdb;
 244         struct net_bridge_mdb_entry *mp;
 245         struct net_bridge_port_group *p;
 246         struct net_bridge_port_group __rcu **pp;
 247
 248         mdb = mlock_dereference(br->mdb, br);
 249
 250         mp = br_mdb_ip_get(mdb, &pg->addr);
 251         if (WARN_ON(!mp))
 252                 return;
 253
 254         for (pp = &mp->ports;
 255              (p = mlock_dereference(*pp, br)) != NULL;
 256              pp = &p->next) {
 257                 if (p != pg)
 258                         continue;
 259
 260                 rcu_assign_pointer(*pp, p->next);
 261                 hlist_del_init(&p->mglist);
 262                 del_timer(&p->timer);
 263                 call_rcu_bh(&p->rcu, br_multicast_free_pg);
 264
 265                 if (!mp->ports && !mp->mglist &&
 266                     netif_running(br->dev))
 267                         mod_timer(&mp->timer, jiffies);
 268
 269                 return;
 270         }
 271
 272         WARN_ON(1);
 273 }
 274
 275 static void br_multicast_port_group_expired(unsigned long data)
 276 {
 277         struct net_bridge_port_group *pg = (void *)data;
 278         struct net_bridge *br = pg->port->br;
 279
 280         spin_lock(&br->multicast_lock);
 281         if (!netif_running(br->dev) || timer_pending(&pg->timer) ||
 282             hlist_unhashed(&pg->mglist) || pg->state & MDB_PERMANENT)
 283                 goto out;
 284
 285         br_multicast_del_pg(br, pg);
 286
 287 out:
 288         spin_unlock(&br->multicast_lock);
 289 }
 290
 291 static int br_mdb_rehash(struct net_bridge_mdb_htable __rcu **mdbp, int max,
 292                          int elasticity)
 293 {
 294         struct net_bridge_mdb_htable *old = rcu_dereference_protected(*mdbp, 1);
 295         struct net_bridge_mdb_htable *mdb;
 296         int err;
 297
 298         mdb = kmalloc(sizeof(*mdb), GFP_ATOMIC);
 299         if (!mdb)
 300                 return -ENOMEM;
 301
 302         mdb->max = max;
 303         mdb->old = old;
 304
 305         mdb->mhash = kzalloc(max * sizeof(*mdb->mhash), GFP_ATOMIC);
 306         if (!mdb->mhash) {
 307                 kfree(mdb);
 308                 return -ENOMEM;
 309         }
 310
 311         mdb->size = old ? old->size : 0;
 312         mdb->ver = old ? old->ver ^ 1 : 0;
 313
 314         if (!old || elasticity)
 315                 get_random_bytes(&mdb->secret, sizeof(mdb->secret));
 316         else
 317                 mdb->secret = old->secret;
 318
 319         if (!old)
 320                 goto out;
 321
 322         err = br_mdb_copy(mdb, old, elasticity);
 323         if (err) {
 324                 kfree(mdb->mhash);
 325                 kfree(mdb);
 326                 return err;
 327         }
 328
 329         br_mdb_rehash_seq++;
 330         call_rcu_bh(&mdb->rcu, br_mdb_free);
 331
 332 out:
 333         rcu_assign_pointer(*mdbp, mdb);
 334
 335         return 0;
 336 }
 337
 338 static struct sk_buff *br_ip4_multicast_alloc_query(struct net_bridge *br,
 339                                                     __be32 group)
 340 {
 341         struct sk_buff *skb;
 342         struct igmphdr *ih;
 343         struct ethhdr *eth;
 344         struct iphdr *iph;
 345
 346         skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*iph) +
 347                                                  sizeof(*ih) + 4);
 348         if (!skb)
 349                 goto out;
 350
 351         skb->protocol = htons(ETH_P_IP);
 352
 353         skb_reset_mac_header(skb);
 354         eth = eth_hdr(skb);
 355
 356         memcpy(eth->h_source, br->dev->dev_addr, 6);
 357         eth->h_dest[0] = 1;
 358         eth->h_dest[1] = 0;
 359         eth->h_dest[2] = 0x5e;
 360         eth->h_dest[3] = 0;
 361         eth->h_dest[4] = 0;
 362         eth->h_dest[5] = 1;
 363         eth->h_proto = htons(ETH_P_IP);
 364         skb_put(skb, sizeof(*eth));
 365
 366         skb_set_network_header(skb, skb->len);
 367         iph = ip_hdr(skb);
 368
 369         iph->version = 4;
 370         iph->ihl = 6;
 371         iph->tos = 0xc0;
 372         iph->tot_len = htons(sizeof(*iph) + sizeof(*ih) + 4);
 373         iph->id = 0;
 374         iph->frag_off = htons(IP_DF);
 375         iph->ttl = 1;
 376         iph->protocol = IPPROTO_IGMP;
 377         iph->saddr = 0;
 378         iph->daddr = htonl(INADDR_ALLHOSTS_GROUP);
 379         ((u8 *)&iph[1])[0] = IPOPT_RA;
 380         ((u8 *)&iph[1])[1] = 4;
 381         ((u8 *)&iph[1])[2] = 0;
 382         ((u8 *)&iph[1])[3] = 0;
 383         ip_send_check(iph);
 384         skb_put(skb, 24);
 385
 386         skb_set_transport_header(skb, skb->len);
 387         ih = igmp_hdr(skb);
 388         ih->type = IGMP_HOST_MEMBERSHIP_QUERY;
 389         ih->code = (group ? br->multicast_last_member_interval :
 390                             br->multicast_query_response_interval) /
 391                    (HZ / IGMP_TIMER_SCALE);
 392         ih->group = group;
 393         ih->csum = 0;
 394         ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
 395         skb_put(skb, sizeof(*ih));
 396
 397         __skb_pull(skb, sizeof(*eth));
 398
 399 out:
 400         return skb;
 401 }
 402
 403 #if IS_ENABLED(CONFIG_IPV6)
 404 static struct sk_buff *br_ip6_multicast_alloc_query(struct net_bridge *br,
 405                                                     const struct in6_addr *group)
 406 {
 407         struct sk_buff *skb;
 408         struct ipv6hdr *ip6h;
 409         struct mld_msg *mldq;
 410         struct ethhdr *eth;
 411         u8 *hopopt;
 412         unsigned long interval;
 413
 414         skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*ip6h) +
 415                                                  8 + sizeof(*mldq));
 416         if (!skb)
 417                 goto out;
 418
 419         skb->protocol = htons(ETH_P_IPV6);
 420
 421         /* Ethernet header */
 422         skb_reset_mac_header(skb);
 423         eth = eth_hdr(skb);
 424
 425         memcpy(eth->h_source, br->dev->dev_addr, 6);
 426         eth->h_proto = htons(ETH_P_IPV6);
 427         skb_put(skb, sizeof(*eth));
 428
 429         /* IPv6 header + HbH option */
 430         skb_set_network_header(skb, skb->len);
 431         ip6h = ipv6_hdr(skb);
 432
 433         *(__force __be32 *)ip6h = htonl(0x60000000);
 434         ip6h->payload_len = htons(8 + sizeof(*mldq));
 435         ip6h->nexthdr = IPPROTO_HOPOPTS;
 436         ip6h->hop_limit = 1;
 437         ipv6_addr_set(&ip6h->daddr, htonl(0xff020000), 0, 0, htonl(1));
 438         if (ipv6_dev_get_saddr(dev_net(br->dev), br->dev, &ip6h->daddr, 0,
 439                                &ip6h->saddr)) {
 440                 kfree_skb(skb);
 441                 return NULL;
 442         }
 443         ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest);
 444
 445         hopopt = (u8 *)(ip6h + 1);
 446         hopopt[0] = IPPROTO_ICMPV6;             /* next hdr */
 447         hopopt[1] = 0;                          /* length of HbH */
 448         hopopt[2] = IPV6_TLV_ROUTERALERT;       /* Router Alert */
 449         hopopt[3] = 2;                          /* Length of RA Option */
 450         hopopt[4] = 0;                          /* Type = 0x0000 (MLD) */
 451         hopopt[5] = 0;
 452         hopopt[6] = IPV6_TLV_PAD1;              /* Pad1 */
 453         hopopt[7] = IPV6_TLV_PAD1;              /* Pad1 */
 454
 455         skb_put(skb, sizeof(*ip6h) + 8);
 456
 457         /* ICMPv6 */
 458         skb_set_transport_header(skb, skb->len);
 459         mldq = (struct mld_msg *) icmp6_hdr(skb);
 460
 461         interval = ipv6_addr_any(group) ? br->multicast_last_member_interval :
 462                                           br->multicast_query_response_interval;
 463
 464         mldq->mld_type = ICMPV6_MGM_QUERY;
 465         mldq->mld_code = 0;
 466         mldq->mld_cksum = 0;
 467         mldq->mld_maxdelay = htons((u16)jiffies_to_msecs(interval));
 468         mldq->mld_reserved = 0;
 469         mldq->mld_mca = *group;
 470
 471         /* checksum */
 472         mldq->mld_cksum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
 473                                           sizeof(*mldq), IPPROTO_ICMPV6,
 474                                           csum_partial(mldq,
 475                                                        sizeof(*mldq), 0));
 476         skb_put(skb, sizeof(*mldq));
 477
 478         __skb_pull(skb, sizeof(*eth));
 479
 480 out:
 481         return skb;
 482 }
 483 #endif
 484
 485 static struct sk_buff *br_multicast_alloc_query(struct net_bridge *br,
 486                                                 struct br_ip *addr)
 487 {
 488         switch (addr->proto) {
 489         case htons(ETH_P_IP):
 490                 return br_ip4_multicast_alloc_query(br, addr->u.ip4);
 491 #if IS_ENABLED(CONFIG_IPV6)
 492         case htons(ETH_P_IPV6):
 493                 return br_ip6_multicast_alloc_query(br, &addr->u.ip6);
 494 #endif
 495         }
 496         return NULL;
 497 }
 498
 499 static struct net_bridge_mdb_entry *br_multicast_get_group(
 500         struct net_bridge *br, struct net_bridge_port *port,
 501         struct br_ip *group, int hash)
 502 {
 503         struct net_bridge_mdb_htable *mdb;
 504         struct net_bridge_mdb_entry *mp;
 505         struct hlist_node *p;
 506         unsigned int count = 0;
 507         unsigned int max;
 508         int elasticity;
 509         int err;
 510
 511         mdb = rcu_dereference_protected(br->mdb, 1);
 512         hlist_for_each_entry(mp, p, &mdb->mhash[hash], hlist[mdb->ver]) {
 513                 count++;
 514                 if (unlikely(br_ip_equal(group, &mp->addr)))
 515                         return mp;
 516         }
 517
 518         elasticity = 0;
 519         max = mdb->max;
 520
 521         if (unlikely(count > br->hash_elasticity && count)) {
 522                 if (net_ratelimit())
 523                         br_info(br, "Multicast hash table "
 524                                 "chain limit reached: %s\n",
 525                                 port ? port->dev->name : br->dev->name);
 526
 527                 elasticity = br->hash_elasticity;
 528         }
 529
 530         if (mdb->size >= max) {
 531                 max *= 2;
 532                 if (unlikely(max > br->hash_max)) {
 533                         br_warn(br, "Multicast hash table maximum of %d "
 534                                 "reached, disabling snooping: %s\n",
 535                                 br->hash_max,
 536                                 port ? port->dev->name : br->dev->name);
 537                         err = -E2BIG;
 538 disable:
 539                         br->multicast_disabled = 1;
 540                         goto err;
 541                 }
 542         }
 543
 544         if (max > mdb->max || elasticity) {
 545                 if (mdb->old) {
 546                         if (net_ratelimit())
 547                                 br_info(br, "Multicast hash table "
 548                                         "on fire: %s\n",
 549                                         port ? port->dev->name : br->dev->name);
 550                         err = -EEXIST;
 551                         goto err;
 552                 }
 553
 554                 err = br_mdb_rehash(&br->mdb, max, elasticity);
 555                 if (err) {
 556                         br_warn(br, "Cannot rehash multicast "
 557                                 "hash table, disabling snooping: %s, %d, %d\n",
 558                                 port ? port->dev->name : br->dev->name,
 559                                 mdb->size, err);
 560                         goto disable;
 561                 }
 562
 563                 err = -EAGAIN;
 564                 goto err;
 565         }
 566
 567         return NULL;
 568
 569 err:
 570         mp = ERR_PTR(err);
 571         return mp;
 572 }
 573
 574 struct net_bridge_mdb_entry *br_multicast_new_group(struct net_bridge *br,
 575         struct net_bridge_port *port, struct br_ip *group)
 576 {
 577         struct net_bridge_mdb_htable *mdb;
 578         struct net_bridge_mdb_entry *mp;
 579         int hash;
 580         int err;
 581
 582         mdb = rcu_dereference_protected(br->mdb, 1);
 583         if (!mdb) {
 584                 err = br_mdb_rehash(&br->mdb, BR_HASH_SIZE, 0);
 585                 if (err)
 586                         return ERR_PTR(err);
 587                 goto rehash;
 588         }
 589
 590         hash = br_ip_hash(mdb, group);
 591         mp = br_multicast_get_group(br, port, group, hash);
 592         switch (PTR_ERR(mp)) {
 593         case 0:
 594                 break;
 595
 596         case -EAGAIN:
 597 rehash:
 598                 mdb = rcu_dereference_protected(br->mdb, 1);
 599                 hash = br_ip_hash(mdb, group);
 600                 break;
 601
 602         default:
 603                 goto out;
 604         }
 605
 606         mp = kzalloc(sizeof(*mp), GFP_ATOMIC);
 607         if (unlikely(!mp))
 608                 return ERR_PTR(-ENOMEM);
 609
 610         mp->br = br;
 611         mp->addr = *group;
 612         setup_timer(&mp->timer, br_multicast_group_expired,
 613                     (unsigned long)mp);
 614
 615         hlist_add_head_rcu(&mp->hlist[mdb->ver], &mdb->mhash[hash]);
 616         mdb->size++;
 617
 618 out:
 619         return mp;
 620 }
 621
 622 struct net_bridge_port_group *br_multicast_new_port_group(
 623                         struct net_bridge_port *port,
 624                         struct br_ip *group,
 625                         struct net_bridge_port_group __rcu *next,
 626                         unsigned char state)
 627 {
 628         struct net_bridge_port_group *p;
 629
 630         p = kzalloc(sizeof(*p), GFP_ATOMIC);
 631         if (unlikely(!p))
 632                 return NULL;
 633
 634         p->addr = *group;
 635         p->port = port;
 636         p->state = state;
 637         rcu_assign_pointer(p->next, next);
 638         hlist_add_head(&p->mglist, &port->mglist);
 639         setup_timer(&p->timer, br_multicast_port_group_expired,
 640                     (unsigned long)p);
 641         return p;
 642 }
 643
 644 static int br_multicast_add_group(struct net_bridge *br,
 645                                   struct net_bridge_port *port,
 646                                   struct br_ip *group)
 647 {
 648         struct net_bridge_mdb_entry *mp;
 649         struct net_bridge_port_group *p;
 650         struct net_bridge_port_group __rcu **pp;
 651         unsigned long now = jiffies;
 652         int err;
 653
 654         spin_lock(&br->multicast_lock);
 655         if (!netif_running(br->dev) ||
 656             (port && port->state == BR_STATE_DISABLED))
 657                 goto out;
 658
 659         mp = br_multicast_new_group(br, port, group);
 660         err = PTR_ERR(mp);
 661         if (IS_ERR(mp))
 662                 goto err;
 663
 664         if (!port) {
 665                 mp->mglist = true;
 666                 mod_timer(&mp->timer, now + br->multicast_membership_interval);
 667                 goto out;
 668         }
 669
 670         for (pp = &mp->ports;
 671              (p = mlock_dereference(*pp, br)) != NULL;
 672              pp = &p->next) {
 673                 if (p->port == port)
 674                         goto found;
 675                 if ((unsigned long)p->port < (unsigned long)port)
 676                         break;
 677         }
 678
 679         p = br_multicast_new_port_group(port, group, *pp, MDB_TEMPORARY);
 680         if (unlikely(!p))
 681                 goto err;
 682         rcu_assign_pointer(*pp, p);
 683         br_mdb_notify(br->dev, port, group, RTM_NEWMDB);
 684
 685 found:
 686         mod_timer(&p->timer, now + br->multicast_membership_interval);
 687 out:
 688         err = 0;
 689
 690 err:
 691         spin_unlock(&br->multicast_lock);
 692         return err;
 693 }
 694
 695 static int br_ip4_multicast_add_group(struct net_bridge *br,
 696                                       struct net_bridge_port *port,
 697                                       __be32 group)
 698 {
 699         struct br_ip br_group;
 700
 701         if (ipv4_is_local_multicast(group))
 702                 return 0;
 703
 704         br_group.u.ip4 = group;
 705         br_group.proto = htons(ETH_P_IP);
 706
 707         return br_multicast_add_group(br, port, &br_group);
 708 }
 709
 710 #if IS_ENABLED(CONFIG_IPV6)
 711 static int br_ip6_multicast_add_group(struct net_bridge *br,
 712                                       struct net_bridge_port *port,
 713                                       const struct in6_addr *group)
 714 {
 715         struct br_ip br_group;
 716
 717         if (!ipv6_is_transient_multicast(group))
 718                 return 0;
 719
 720         br_group.u.ip6 = *group;
 721         br_group.proto = htons(ETH_P_IPV6);
 722
 723         return br_multicast_add_group(br, port, &br_group);
 724 }
 725 #endif
 726
 727 static void br_multicast_router_expired(unsigned long data)
 728 {
 729         struct net_bridge_port *port = (void *)data;
 730         struct net_bridge *br = port->br;
 731
 732         spin_lock(&br->multicast_lock);
 733         if (port->multicast_router != 1 ||
 734             timer_pending(&port->multicast_router_timer) ||
 735             hlist_unhashed(&port->rlist))
 736                 goto out;
 737
 738         hlist_del_init_rcu(&port->rlist);
 739
 740 out:
 741         spin_unlock(&br->multicast_lock);
 742 }
 743
 744 static void br_multicast_local_router_expired(unsigned long data)
 745 {
 746 }
 747
 748 static void br_multicast_querier_expired(unsigned long data)
 749 {
 750         struct net_bridge *br = (void *)data;
 751
 752         spin_lock(&br->multicast_lock);
 753         if (!netif_running(br->dev) || br->multicast_disabled)
 754                 goto out;
 755
 756         br_multicast_start_querier(br);
 757
 758 out:
 759         spin_unlock(&br->multicast_lock);
 760 }
 761
 762 static void __br_multicast_send_query(struct net_bridge *br,
 763                                       struct net_bridge_port *port,
 764                                       struct br_ip *ip)
 765 {
 766         struct sk_buff *skb;
 767
 768         skb = br_multicast_alloc_query(br, ip);
 769         if (!skb)
 770                 return;
 771
 772         if (port) {
 773                 __skb_push(skb, sizeof(struct ethhdr));
 774                 skb->dev = port->dev;
 775                 NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
 776                         dev_queue_xmit);
 777         } else
 778                 netif_rx(skb);
 779 }
 780
 781 static void br_multicast_send_query(struct net_bridge *br,
 782                                     struct net_bridge_port *port, u32 sent)
 783 {
 784         unsigned long time;
 785         struct br_ip br_group;
 786
 787         if (!netif_running(br->dev) || br->multicast_disabled ||
 788             !br->multicast_querier ||
 789             timer_pending(&br->multicast_querier_timer))
 790                 return;
 791
 792         memset(&br_group.u, 0, sizeof(br_group.u));
 793
 794         br_group.proto = htons(ETH_P_IP);
 795         __br_multicast_send_query(br, port, &br_group);
 796
 797 #if IS_ENABLED(CONFIG_IPV6)
 798         br_group.proto = htons(ETH_P_IPV6);
 799         __br_multicast_send_query(br, port, &br_group);
 800 #endif
 801
 802         time = jiffies;
 803         time += sent < br->multicast_startup_query_count ?
 804                 br->multicast_startup_query_interval :
 805                 br->multicast_query_interval;
 806         mod_timer(port ? &port->multicast_query_timer :
 807                          &br->multicast_query_timer, time);
 808 }
 809
 810 static void br_multicast_port_query_expired(unsigned long data)
 811 {
 812         struct net_bridge_port *port = (void *)data;
 813         struct net_bridge *br = port->br;
 814
 815         spin_lock(&br->multicast_lock);
 816         if (port->state == BR_STATE_DISABLED ||
 817             port->state == BR_STATE_BLOCKING)
 818                 goto out;
 819
 820         if (port->multicast_startup_queries_sent <
 821             br->multicast_startup_query_count)
 822                 port->multicast_startup_queries_sent++;
 823
 824         br_multicast_send_query(port->br, port,
 825                                 port->multicast_startup_queries_sent);
 826
 827 out:
 828         spin_unlock(&br->multicast_lock);
 829 }
 830
 831 void br_multicast_add_port(struct net_bridge_port *port)
 832 {
 833         port->multicast_router = 1;
 834
 835         setup_timer(&port->multicast_router_timer, br_multicast_router_expired,
 836                     (unsigned long)port);
 837         setup_timer(&port->multicast_query_timer,
 838                     br_multicast_port_query_expired, (unsigned long)port);
 839 }
 840
 841 void br_multicast_del_port(struct net_bridge_port *port)
 842 {
 843         del_timer_sync(&port->multicast_router_timer);
 844 }
 845
 846 static void __br_multicast_enable_port(struct net_bridge_port *port)
 847 {
 848         port->multicast_startup_queries_sent = 0;
 849
 850         if (try_to_del_timer_sync(&port->multicast_query_timer) >= 0 ||
 851             del_timer(&port->multicast_query_timer))
 852                 mod_timer(&port->multicast_query_timer, jiffies);
 853 }
 854
 855 void br_multicast_enable_port(struct net_bridge_port *port)
 856 {
 857         struct net_bridge *br = port->br;
 858
 859         spin_lock(&br->multicast_lock);
 860         if (br->multicast_disabled || !netif_running(br->dev))
 861                 goto out;
 862
 863         __br_multicast_enable_port(port);
 864
 865 out:
 866         spin_unlock(&br->multicast_lock);
 867 }
 868
 869 void br_multicast_disable_port(struct net_bridge_port *port)
 870 {
 871         struct net_bridge *br = port->br;
 872         struct net_bridge_port_group *pg;
 873         struct hlist_node *p, *n;
 874
 875         spin_lock(&br->multicast_lock);
 876         hlist_for_each_entry_safe(pg, p, n, &port->mglist, mglist)
 877                 br_multicast_del_pg(br, pg);
 878
 879         if (!hlist_unhashed(&port->rlist))
 880                 hlist_del_init_rcu(&port->rlist);
 881         del_timer(&port->multicast_router_timer);
 882         del_timer(&port->multicast_query_timer);
 883         spin_unlock(&br->multicast_lock);
 884 }
 885
 886 static int br_ip4_multicast_igmp3_report(struct net_bridge *br,
 887                                          struct net_bridge_port *port,
 888                                          struct sk_buff *skb)
 889 {
 890         struct igmpv3_report *ih;
 891         struct igmpv3_grec *grec;
 892         int i;
 893         int len;
 894         int num;
 895         int type;
 896         int err = 0;
 897         __be32 group;
 898
 899         if (!pskb_may_pull(skb, sizeof(*ih)))
 900                 return -EINVAL;
 901
 902         ih = igmpv3_report_hdr(skb);
 903         num = ntohs(ih->ngrec);
 904         len = sizeof(*ih);
 905
 906         for (i = 0; i < num; i++) {
 907                 len += sizeof(*grec);
 908                 if (!pskb_may_pull(skb, len))
 909                         return -EINVAL;
 910
 911                 grec = (void *)(skb->data + len - sizeof(*grec));
 912                 group = grec->grec_mca;
 913                 type = grec->grec_type;
 914
 915                 len += ntohs(grec->grec_nsrcs) * 4;
 916                 if (!pskb_may_pull(skb, len))
 917                         return -EINVAL;
 918
 919                 /* We treat this as an IGMPv2 report for now. */
 920                 switch (type) {
 921                 case IGMPV3_MODE_IS_INCLUDE:
 922                 case IGMPV3_MODE_IS_EXCLUDE:
 923                 case IGMPV3_CHANGE_TO_INCLUDE:
 924                 case IGMPV3_CHANGE_TO_EXCLUDE:
 925                 case IGMPV3_ALLOW_NEW_SOURCES:
 926                 case IGMPV3_BLOCK_OLD_SOURCES:
 927                         break;
 928
 929                 default:
 930                         continue;
 931                 }
 932
 933                 err = br_ip4_multicast_add_group(br, port, group);
 934                 if (err)
 935                         break;
 936         }
 937
 938         return err;
 939 }
 940
 941 #if IS_ENABLED(CONFIG_IPV6)
 942 static int br_ip6_multicast_mld2_report(struct net_bridge *br,
 943                                         struct net_bridge_port *port,
 944                                         struct sk_buff *skb)
 945 {
 946         struct icmp6hdr *icmp6h;
 947         struct mld2_grec *grec;
 948         int i;
 949         int len;
 950         int num;
 951         int err = 0;
 952
 953         if (!pskb_may_pull(skb, sizeof(*icmp6h)))
 954                 return -EINVAL;
 955
 956         icmp6h = icmp6_hdr(skb);
 957         num = ntohs(icmp6h->icmp6_dataun.un_data16[1]);
 958         len = sizeof(*icmp6h);
 959
 960         for (i = 0; i < num; i++) {
 961                 __be16 *nsrcs, _nsrcs;
 962
 963                 nsrcs = skb_header_pointer(skb,
 964                                            len + offsetof(struct mld2_grec,
 965                                                           grec_nsrcs),
 966                                            sizeof(_nsrcs), &_nsrcs);
 967                 if (!nsrcs)
 968                         return -EINVAL;
 969
 970                 if (!pskb_may_pull(skb,
 971                                    len + sizeof(*grec) +
 972                                    sizeof(struct in6_addr) * ntohs(*nsrcs)))
 973                         return -EINVAL;
 974
 975                 grec = (struct mld2_grec *)(skb->data + len);
 976                 len += sizeof(*grec) +
 977                        sizeof(struct in6_addr) * ntohs(*nsrcs);
 978
 979                 /* We treat these as MLDv1 reports for now. */
 980                 switch (grec->grec_type) {
 981                 case MLD2_MODE_IS_INCLUDE:
 982                 case MLD2_MODE_IS_EXCLUDE:
 983                 case MLD2_CHANGE_TO_INCLUDE:
 984                 case MLD2_CHANGE_TO_EXCLUDE:
 985                 case MLD2_ALLOW_NEW_SOURCES:
 986                 case MLD2_BLOCK_OLD_SOURCES:
 987                         break;
 988
 989                 default:
 990                         continue;
 991                 }
 992
 993                 err = br_ip6_multicast_add_group(br, port, &grec->grec_mca);
 994                 if (!err)
 995                         break;
 996         }
 997
 998         return err;
 999 }
1000 #endif
1001
1002 /*
1003  * Add port to rotuer_list
1004  *  list is maintained ordered by pointer value
1005  *  and locked by br->multicast_lock and RCU
1006  */
1007 static void br_multicast_add_router(struct net_bridge *br,
1008                                     struct net_bridge_port *port)
1009 {
1010         struct net_bridge_port *p;
1011         struct hlist_node *n, *slot = NULL;
1012
1013         hlist_for_each_entry(p, n, &br->router_list, rlist) {
1014                 if ((unsigned long) port >= (unsigned long) p)
1015                         break;
1016                 slot = n;
1017         }
1018
1019         if (slot)
1020                 hlist_add_after_rcu(slot, &port->rlist);
1021         else
1022                 hlist_add_head_rcu(&port->rlist, &br->router_list);
1023 }
1024
1025 static void br_multicast_mark_router(struct net_bridge *br,
1026                                      struct net_bridge_port *port)
1027 {
1028         unsigned long now = jiffies;
1029
1030         if (!port) {
1031                 if (br->multicast_router == 1)
1032                         mod_timer(&br->multicast_router_timer,
1033                                   now + br->multicast_querier_interval);
1034                 return;
1035         }
1036
1037         if (port->multicast_router != 1)
1038                 return;
1039
1040         if (!hlist_unhashed(&port->rlist))
1041                 goto timer;
1042
1043         br_multicast_add_router(br, port);
1044
1045 timer:
1046         mod_timer(&port->multicast_router_timer,
1047                   now + br->multicast_querier_interval);
1048 }
1049
1050 static void br_multicast_query_received(struct net_bridge *br,
1051                                         struct net_bridge_port *port,
1052                                         int saddr)
1053 {
1054         if (saddr)
1055                 mod_timer(&br->multicast_querier_timer,
1056                           jiffies + br->multicast_querier_interval);
1057         else if (timer_pending(&br->multicast_querier_timer))
1058                 return;
1059
1060         br_multicast_mark_router(br, port);
1061 }
1062
1063 static int br_ip4_multicast_query(struct net_bridge *br,
1064                                   struct net_bridge_port *port,
1065                                   struct sk_buff *skb)
1066 {
1067         const struct iphdr *iph = ip_hdr(skb);
1068         struct igmphdr *ih = igmp_hdr(skb);
1069         struct net_bridge_mdb_entry *mp;
1070         struct igmpv3_query *ih3;
1071         struct net_bridge_port_group *p;
1072         struct net_bridge_port_group __rcu **pp;
1073         unsigned long max_delay;
1074         unsigned long now = jiffies;
1075         __be32 group;
1076         int err = 0;
1077
1078         spin_lock(&br->multicast_lock);
1079         if (!netif_running(br->dev) ||
1080             (port && port->state == BR_STATE_DISABLED))
1081                 goto out;
1082
1083         br_multicast_query_received(br, port, !!iph->saddr);
1084
1085         group = ih->group;
1086
1087         if (skb->len == sizeof(*ih)) {
1088                 max_delay = ih->code * (HZ / IGMP_TIMER_SCALE);
1089
1090                 if (!max_delay) {
1091                         max_delay = 10 * HZ;
1092                         group = 0;
1093                 }
1094         } else {
1095                 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query))) {
1096                         err = -EINVAL;
1097                         goto out;
1098                 }
1099
1100                 ih3 = igmpv3_query_hdr(skb);
1101                 if (ih3->nsrcs)
1102                         goto out;
1103
1104                 max_delay = ih3->code ?
1105                             IGMPV3_MRC(ih3->code) * (HZ / IGMP_TIMER_SCALE) : 1;
1106         }
1107
1108         if (!group)
1109                 goto out;
1110
1111         mp = br_mdb_ip4_get(mlock_dereference(br->mdb, br), group);
1112         if (!mp)
1113                 goto out;
1114
1115         max_delay *= br->multicast_last_member_count;
1116
1117         if (mp->mglist &&
1118             (timer_pending(&mp->timer) ?
1119              time_after(mp->timer.expires, now + max_delay) :
1120              try_to_del_timer_sync(&mp->timer) >= 0))
1121                 mod_timer(&mp->timer, now + max_delay);
1122
1123         for (pp = &mp->ports;
1124              (p = mlock_dereference(*pp, br)) != NULL;
1125              pp = &p->next) {
1126                 if (timer_pending(&p->timer) ?
1127                     time_after(p->timer.expires, now + max_delay) :
1128                     try_to_del_timer_sync(&p->timer) >= 0)
1129                         mod_timer(&p->timer, now + max_delay);
1130         }
1131
1132 out:
1133         spin_unlock(&br->multicast_lock);
1134         return err;
1135 }
1136
1137 #if IS_ENABLED(CONFIG_IPV6)
1138 static int br_ip6_multicast_query(struct net_bridge *br,
1139                                   struct net_bridge_port *port,
1140                                   struct sk_buff *skb)
1141 {
1142         const struct ipv6hdr *ip6h = ipv6_hdr(skb);
1143         struct mld_msg *mld;
1144         struct net_bridge_mdb_entry *mp;
1145         struct mld2_query *mld2q;
1146         struct net_bridge_port_group *p;
1147         struct net_bridge_port_group __rcu **pp;
1148         unsigned long max_delay;
1149         unsigned long now = jiffies;
1150         const struct in6_addr *group = NULL;
1151         int err = 0;
1152
1153         spin_lock(&br->multicast_lock);
1154         if (!netif_running(br->dev) ||
1155             (port && port->state == BR_STATE_DISABLED))
1156                 goto out;
1157
1158         br_multicast_query_received(br, port, !ipv6_addr_any(&ip6h->saddr));
1159
1160         if (skb->len == sizeof(*mld)) {
1161                 if (!pskb_may_pull(skb, sizeof(*mld))) {
1162                         err = -EINVAL;
1163                         goto out;
1164                 }
1165                 mld = (struct mld_msg *) icmp6_hdr(skb);
1166                 max_delay = msecs_to_jiffies(ntohs(mld->mld_maxdelay));
1167                 if (max_delay)
1168                         group = &mld->mld_mca;
1169         } else if (skb->len >= sizeof(*mld2q)) {
1170                 if (!pskb_may_pull(skb, sizeof(*mld2q))) {
1171                         err = -EINVAL;
1172                         goto out;
1173                 }
1174                 mld2q = (struct mld2_query *)icmp6_hdr(skb);
1175                 if (!mld2q->mld2q_nsrcs)
1176                         group = &mld2q->mld2q_mca;
1177                 max_delay = mld2q->mld2q_mrc ? MLDV2_MRC(ntohs(mld2q->mld2q_mrc)) : 1;
1178         }
1179
1180         if (!group)
1181                 goto out;
1182
1183         mp = br_mdb_ip6_get(mlock_dereference(br->mdb, br), group);
1184         if (!mp)
1185                 goto out;
1186
1187         max_delay *= br->multicast_last_member_count;
1188         if (mp->mglist &&
1189             (timer_pending(&mp->timer) ?
1190              time_after(mp->timer.expires, now + max_delay) :
1191              try_to_del_timer_sync(&mp->timer) >= 0))
1192                 mod_timer(&mp->timer, now + max_delay);
1193
1194         for (pp = &mp->ports;
1195              (p = mlock_dereference(*pp, br)) != NULL;
1196              pp = &p->next) {
1197                 if (timer_pending(&p->timer) ?
1198                     time_after(p->timer.expires, now + max_delay) :
1199                     try_to_del_timer_sync(&p->timer) >= 0)
1200                         mod_timer(&p->timer, now + max_delay);
1201         }
1202
1203 out:
1204         spin_unlock(&br->multicast_lock);
1205         return err;
1206 }
1207 #endif
1208
1209 static void br_multicast_leave_group(struct net_bridge *br,
1210                                      struct net_bridge_port *port,
1211                                      struct br_ip *group)
1212 {
1213         struct net_bridge_mdb_htable *mdb;
1214         struct net_bridge_mdb_entry *mp;
1215         struct net_bridge_port_group *p;
1216         unsigned long now;
1217         unsigned long time;
1218
1219         spin_lock(&br->multicast_lock);
1220         if (!netif_running(br->dev) ||
1221             (port && port->state == BR_STATE_DISABLED) ||
1222             timer_pending(&br->multicast_querier_timer))
1223                 goto out;
1224
1225         mdb = mlock_dereference(br->mdb, br);
1226         mp = br_mdb_ip_get(mdb, group);
1227         if (!mp)
1228                 goto out;
1229
1230         if (port && (port->flags & BR_MULTICAST_FAST_LEAVE)) {
1231                 struct net_bridge_port_group __rcu **pp;
1232
1233                 for (pp = &mp->ports;
1234                      (p = mlock_dereference(*pp, br)) != NULL;
1235                      pp = &p->next) {
1236                         if (p->port != port)
1237                                 continue;
1238
1239                         rcu_assign_pointer(*pp, p->next);
1240                         hlist_del_init(&p->mglist);
1241                         del_timer(&p->timer);
1242                         call_rcu_bh(&p->rcu, br_multicast_free_pg);
1243                         br_mdb_notify(br->dev, port, group, RTM_DELMDB);
1244
1245                         if (!mp->ports && !mp->mglist &&
1246                             netif_running(br->dev))
1247                                 mod_timer(&mp->timer, jiffies);
1248                 }
1249                 goto out;
1250         }
1251
1252         now = jiffies;
1253         time = now + br->multicast_last_member_count *
1254                      br->multicast_last_member_interval;
1255
1256         if (!port) {
1257                 if (mp->mglist &&
1258                     (timer_pending(&mp->timer) ?
1259                      time_after(mp->timer.expires, time) :
1260                      try_to_del_timer_sync(&mp->timer) >= 0)) {
1261                         mod_timer(&mp->timer, time);
1262                 }
1263
1264                 goto out;
1265         }
1266
1267         for (p = mlock_dereference(mp->ports, br);
1268              p != NULL;
1269              p = mlock_dereference(p->next, br)) {
1270                 if (p->port != port)
1271                         continue;
1272
1273                 if (!hlist_unhashed(&p->mglist) &&
1274                     (timer_pending(&p->timer) ?
1275                      time_after(p->timer.expires, time) :
1276                      try_to_del_timer_sync(&p->timer) >= 0)) {
1277                         mod_timer(&p->timer, time);
1278                 }
1279
1280                 break;
1281         }
1282
1283 out:
1284         spin_unlock(&br->multicast_lock);
1285 }
1286
1287 static void br_ip4_multicast_leave_group(struct net_bridge *br,
1288                                          struct net_bridge_port *port,
1289                                          __be32 group)
1290 {
1291         struct br_ip br_group;
1292
1293         if (ipv4_is_local_multicast(group))
1294                 return;
1295
1296         br_group.u.ip4 = group;
1297         br_group.proto = htons(ETH_P_IP);
1298
1299         br_multicast_leave_group(br, port, &br_group);
1300 }
1301
1302 #if IS_ENABLED(CONFIG_IPV6)
1303 static void br_ip6_multicast_leave_group(struct net_bridge *br,
1304                                          struct net_bridge_port *port,
1305                                          const struct in6_addr *group)
1306 {
1307         struct br_ip br_group;
1308
1309         if (!ipv6_is_transient_multicast(group))
1310                 return;
1311
1312         br_group.u.ip6 = *group;
1313         br_group.proto = htons(ETH_P_IPV6);
1314
1315         br_multicast_leave_group(br, port, &br_group);
1316 }
1317 #endif
1318
1319 static int br_multicast_ipv4_rcv(struct net_bridge *br,
1320                                  struct net_bridge_port *port,
1321                                  struct sk_buff *skb)
1322 {
1323         struct sk_buff *skb2 = skb;
1324         const struct iphdr *iph;
1325         struct igmphdr *ih;
1326         unsigned int len;
1327         unsigned int offset;
1328         int err;
1329
1330         /* We treat OOM as packet loss for now. */
1331         if (!pskb_may_pull(skb, sizeof(*iph)))
1332                 return -EINVAL;
1333
1334         iph = ip_hdr(skb);
1335
1336         if (iph->ihl < 5 || iph->version != 4)
1337                 return -EINVAL;
1338
1339         if (!pskb_may_pull(skb, ip_hdrlen(skb)))
1340                 return -EINVAL;
1341
1342         iph = ip_hdr(skb);
1343
1344         if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1345                 return -EINVAL;
1346
1347         if (iph->protocol != IPPROTO_IGMP) {
1348                 if ((iph->daddr & IGMP_LOCAL_GROUP_MASK) != IGMP_LOCAL_GROUP)
1349                         BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1350                 return 0;
1351         }
1352
1353         len = ntohs(iph->tot_len);
1354         if (skb->len < len || len < ip_hdrlen(skb))
1355                 return -EINVAL;
1356
1357         if (skb->len > len) {
1358                 skb2 = skb_clone(skb, GFP_ATOMIC);
1359                 if (!skb2)
1360                         return -ENOMEM;
1361
1362                 err = pskb_trim_rcsum(skb2, len);
1363                 if (err)
1364                         goto err_out;
1365         }
1366
1367         len -= ip_hdrlen(skb2);
1368         offset = skb_network_offset(skb2) + ip_hdrlen(skb2);
1369         __skb_pull(skb2, offset);
1370         skb_reset_transport_header(skb2);
1371
1372         err = -EINVAL;
1373         if (!pskb_may_pull(skb2, sizeof(*ih)))
1374                 goto out;
1375
1376         switch (skb2->ip_summed) {
1377         case CHECKSUM_COMPLETE:
1378                 if (!csum_fold(skb2->csum))
1379                         break;
1380                 /* fall through */
1381         case CHECKSUM_NONE:
1382                 skb2->csum = 0;
1383                 if (skb_checksum_complete(skb2))
1384                         goto out;
1385         }
1386
1387         err = 0;
1388
1389         BR_INPUT_SKB_CB(skb)->igmp = 1;
1390         ih = igmp_hdr(skb2);
1391
1392         switch (ih->type) {
1393         case IGMP_HOST_MEMBERSHIP_REPORT:
1394         case IGMPV2_HOST_MEMBERSHIP_REPORT:
1395                 BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1396                 err = br_ip4_multicast_add_group(br, port, ih->group);
1397                 break;
1398         case IGMPV3_HOST_MEMBERSHIP_REPORT:
1399                 err = br_ip4_multicast_igmp3_report(br, port, skb2);
1400                 break;
1401         case IGMP_HOST_MEMBERSHIP_QUERY:
1402                 err = br_ip4_multicast_query(br, port, skb2);
1403                 break;
1404         case IGMP_HOST_LEAVE_MESSAGE:
1405                 br_ip4_multicast_leave_group(br, port, ih->group);
1406                 break;
1407         }
1408
1409 out:
1410         __skb_push(skb2, offset);
1411 err_out:
1412         if (skb2 != skb)
1413                 kfree_skb(skb2);
1414         return err;
1415 }
1416
1417 #if IS_ENABLED(CONFIG_IPV6)
1418 static int br_multicast_ipv6_rcv(struct net_bridge *br,
1419                                  struct net_bridge_port *port,
1420                                  struct sk_buff *skb)
1421 {
1422         struct sk_buff *skb2;
1423         const struct ipv6hdr *ip6h;
1424         u8 icmp6_type;
1425         u8 nexthdr;
1426         __be16 frag_off;
1427         unsigned int len;
1428         int offset;
1429         int err;
1430
1431         if (!pskb_may_pull(skb, sizeof(*ip6h)))
1432                 return -EINVAL;
1433
1434         ip6h = ipv6_hdr(skb);
1435
1436         /*
1437          * We're interested in MLD messages only.
1438          *  - Version is 6
1439          *  - MLD has always Router Alert hop-by-hop option
1440          *  - But we do not support jumbrograms.
1441          */
1442         if (ip6h->version != 6 ||
1443             ip6h->nexthdr != IPPROTO_HOPOPTS ||
1444             ip6h->payload_len == 0)
1445                 return 0;
1446
1447         len = ntohs(ip6h->payload_len) + sizeof(*ip6h);
1448         if (skb->len < len)
1449                 return -EINVAL;
1450
1451         nexthdr = ip6h->nexthdr;
1452         offset = ipv6_skip_exthdr(skb, sizeof(*ip6h), &nexthdr, &frag_off);
1453
1454         if (offset < 0 || nexthdr != IPPROTO_ICMPV6)
1455                 return 0;
1456
1457         /* Okay, we found ICMPv6 header */
1458         skb2 = skb_clone(skb, GFP_ATOMIC);
1459         if (!skb2)
1460                 return -ENOMEM;
1461
1462         err = -EINVAL;
1463         if (!pskb_may_pull(skb2, offset + sizeof(struct icmp6hdr)))
1464                 goto out;
1465
1466         len -= offset - skb_network_offset(skb2);
1467
1468         __skb_pull(skb2, offset);
1469         skb_reset_transport_header(skb2);
1470         skb_postpull_rcsum(skb2, skb_network_header(skb2),
1471                            skb_network_header_len(skb2));
1472
1473         icmp6_type = icmp6_hdr(skb2)->icmp6_type;
1474
1475         switch (icmp6_type) {
1476         case ICMPV6_MGM_QUERY:
1477         case ICMPV6_MGM_REPORT:
1478         case ICMPV6_MGM_REDUCTION:
1479         case ICMPV6_MLD2_REPORT:
1480                 break;
1481         default:
1482                 err = 0;
1483                 goto out;
1484         }
1485
1486         /* Okay, we found MLD message. Check further. */
1487         if (skb2->len > len) {
1488                 err = pskb_trim_rcsum(skb2, len);
1489                 if (err)
1490                         goto out;
1491                 err = -EINVAL;
1492         }
1493
1494         ip6h = ipv6_hdr(skb2);
1495
1496         switch (skb2->ip_summed) {
1497         case CHECKSUM_COMPLETE:
1498                 if (!csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, skb2->len,
1499                                         IPPROTO_ICMPV6, skb2->csum))
1500                         break;
1501                 /*FALLTHROUGH*/
1502         case CHECKSUM_NONE:
1503                 skb2->csum = ~csum_unfold(csum_ipv6_magic(&ip6h->saddr,
1504                                                         &ip6h->daddr,
1505                                                         skb2->len,
1506                                                         IPPROTO_ICMPV6, 0));
1507                 if (__skb_checksum_complete(skb2))
1508                         goto out;
1509         }
1510
1511         err = 0;
1512
1513         BR_INPUT_SKB_CB(skb)->igmp = 1;
1514
1515         switch (icmp6_type) {
1516         case ICMPV6_MGM_REPORT:
1517             {
1518                 struct mld_msg *mld;
1519                 if (!pskb_may_pull(skb2, sizeof(*mld))) {
1520                         err = -EINVAL;
1521                         goto out;
1522                 }
1523                 mld = (struct mld_msg *)skb_transport_header(skb2);
1524                 BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1525                 err = br_ip6_multicast_add_group(br, port, &mld->mld_mca);
1526                 break;
1527             }
1528         case ICMPV6_MLD2_REPORT:
1529                 err = br_ip6_multicast_mld2_report(br, port, skb2);
1530                 break;
1531         case ICMPV6_MGM_QUERY:
1532                 err = br_ip6_multicast_query(br, port, skb2);
1533                 break;
1534         case ICMPV6_MGM_REDUCTION:
1535             {
1536                 struct mld_msg *mld;
1537                 if (!pskb_may_pull(skb2, sizeof(*mld))) {
1538                         err = -EINVAL;
1539                         goto out;
1540                 }
1541                 mld = (struct mld_msg *)skb_transport_header(skb2);
1542                 br_ip6_multicast_leave_group(br, port, &mld->mld_mca);
1543             }
1544         }
1545
1546 out:
1547         kfree_skb(skb2);
1548         return err;
1549 }
1550 #endif
1551
1552 int br_multicast_rcv(struct net_bridge *br, struct net_bridge_port *port,
1553                      struct sk_buff *skb)
1554 {
1555         BR_INPUT_SKB_CB(skb)->igmp = 0;
1556         BR_INPUT_SKB_CB(skb)->mrouters_only = 0;
1557
1558         if (br->multicast_disabled)
1559                 return 0;
1560
1561         switch (skb->protocol) {
1562         case htons(ETH_P_IP):
1563                 return br_multicast_ipv4_rcv(br, port, skb);
1564 #if IS_ENABLED(CONFIG_IPV6)
1565         case htons(ETH_P_IPV6):
1566                 return br_multicast_ipv6_rcv(br, port, skb);
1567 #endif
1568         }
1569
1570         return 0;
1571 }
1572
1573 static void br_multicast_query_expired(unsigned long data)
1574 {
1575         struct net_bridge *br = (void *)data;
1576
1577         spin_lock(&br->multicast_lock);
1578         if (br->multicast_startup_queries_sent <
1579             br->multicast_startup_query_count)
1580                 br->multicast_startup_queries_sent++;
1581
1582         br_multicast_send_query(br, NULL, br->multicast_startup_queries_sent);
1583
1584         spin_unlock(&br->multicast_lock);
1585 }
1586
1587 void br_multicast_init(struct net_bridge *br)
1588 {
1589         br->hash_elasticity = 4;
1590         br->hash_max = 512;
1591
1592         br->multicast_router = 1;
1593         br->multicast_querier = 0;
1594         br->multicast_last_member_count = 2;
1595         br->multicast_startup_query_count = 2;
1596
1597         br->multicast_last_member_interval = HZ;
1598         br->multicast_query_response_interval = 10 * HZ;
1599         br->multicast_startup_query_interval = 125 * HZ / 4;
1600         br->multicast_query_interval = 125 * HZ;
1601         br->multicast_querier_interval = 255 * HZ;
1602         br->multicast_membership_interval = 260 * HZ;
1603
1604         spin_lock_init(&br->multicast_lock);
1605         setup_timer(&br->multicast_router_timer,
1606                     br_multicast_local_router_expired, 0);
1607         setup_timer(&br->multicast_querier_timer,
1608                     br_multicast_querier_expired, (unsigned long)br);
1609         setup_timer(&br->multicast_query_timer, br_multicast_query_expired,
1610                     (unsigned long)br);
1611 }
1612
1613 void br_multicast_open(struct net_bridge *br)
1614 {
1615         br->multicast_startup_queries_sent = 0;
1616
1617         if (br->multicast_disabled)
1618                 return;
1619
1620         mod_timer(&br->multicast_query_timer, jiffies);
1621 }
1622
1623 void br_multicast_stop(struct net_bridge *br)
1624 {
1625         struct net_bridge_mdb_htable *mdb;
1626         struct net_bridge_mdb_entry *mp;
1627         struct hlist_node *p, *n;
1628         u32 ver;
1629         int i;
1630
1631         del_timer_sync(&br->multicast_router_timer);
1632         del_timer_sync(&br->multicast_querier_timer);
1633         del_timer_sync(&br->multicast_query_timer);
1634
1635         spin_lock_bh(&br->multicast_lock);
1636         mdb = mlock_dereference(br->mdb, br);
1637         if (!mdb)
1638                 goto out;
1639
1640         br->mdb = NULL;
1641
1642         ver = mdb->ver;
1643         for (i = 0; i < mdb->max; i++) {
1644                 hlist_for_each_entry_safe(mp, p, n, &mdb->mhash[i],
1645                                           hlist[ver]) {
1646                         del_timer(&mp->timer);
1647                         call_rcu_bh(&mp->rcu, br_multicast_free_group);
1648                 }
1649         }
1650
1651         if (mdb->old) {
1652                 spin_unlock_bh(&br->multicast_lock);
1653                 rcu_barrier_bh();
1654                 spin_lock_bh(&br->multicast_lock);
1655                 WARN_ON(mdb->old);
1656         }
1657
1658         mdb->old = mdb;
1659         call_rcu_bh(&mdb->rcu, br_mdb_free);
1660
1661 out:
1662         spin_unlock_bh(&br->multicast_lock);
1663 }
1664
1665 int br_multicast_set_router(struct net_bridge *br, unsigned long val)
1666 {
1667         int err = -ENOENT;
1668
1669         spin_lock_bh(&br->multicast_lock);
1670         if (!netif_running(br->dev))
1671                 goto unlock;
1672
1673         switch (val) {
1674         case 0:
1675         case 2:
1676                 del_timer(&br->multicast_router_timer);
1677                 /* fall through */
1678         case 1:
1679                 br->multicast_router = val;
1680                 err = 0;
1681                 break;
1682
1683         default:
1684                 err = -EINVAL;
1685                 break;
1686         }
1687
1688 unlock:
1689         spin_unlock_bh(&br->multicast_lock);
1690
1691         return err;
1692 }
1693
1694 int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
1695 {
1696         struct net_bridge *br = p->br;
1697         int err = -ENOENT;
1698
1699         spin_lock(&br->multicast_lock);
1700         if (!netif_running(br->dev) || p->state == BR_STATE_DISABLED)
1701                 goto unlock;
1702
1703         switch (val) {
1704         case 0:
1705         case 1:
1706         case 2:
1707                 p->multicast_router = val;
1708                 err = 0;
1709
1710                 if (val < 2 && !hlist_unhashed(&p->rlist))
1711                         hlist_del_init_rcu(&p->rlist);
1712
1713                 if (val == 1)
1714                         break;
1715
1716                 del_timer(&p->multicast_router_timer);
1717
1718                 if (val == 0)
1719                         break;
1720
1721                 br_multicast_add_router(br, p);
1722                 break;
1723
1724         default:
1725                 err = -EINVAL;
1726                 break;
1727         }
1728
1729 unlock:
1730         spin_unlock(&br->multicast_lock);
1731
1732         return err;
1733 }
1734
1735 static void br_multicast_start_querier(struct net_bridge *br)
1736 {
1737         struct net_bridge_port *port;
1738
1739         br_multicast_open(br);
1740
1741         list_for_each_entry(port, &br->port_list, list) {
1742                 if (port->state == BR_STATE_DISABLED ||
1743                     port->state == BR_STATE_BLOCKING)
1744                         continue;
1745
1746                 __br_multicast_enable_port(port);
1747         }
1748 }
1749
1750 int br_multicast_toggle(struct net_bridge *br, unsigned long val)
1751 {
1752         int err = 0;
1753         struct net_bridge_mdb_htable *mdb;
1754
1755         spin_lock_bh(&br->multicast_lock);
1756         if (br->multicast_disabled == !val)
1757                 goto unlock;
1758
1759         br->multicast_disabled = !val;
1760         if (br->multicast_disabled)
1761                 goto unlock;
1762
1763         if (!netif_running(br->dev))
1764                 goto unlock;
1765
1766         mdb = mlock_dereference(br->mdb, br);
1767         if (mdb) {
1768                 if (mdb->old) {
1769                         err = -EEXIST;
1770 rollback:
1771                         br->multicast_disabled = !!val;
1772                         goto unlock;
1773                 }
1774
1775                 err = br_mdb_rehash(&br->mdb, mdb->max,
1776                                     br->hash_elasticity);
1777                 if (err)
1778                         goto rollback;
1779         }
1780
1781         br_multicast_start_querier(br);
1782
1783 unlock:
1784         spin_unlock_bh(&br->multicast_lock);
1785
1786         return err;
1787 }
1788
1789 int br_multicast_set_querier(struct net_bridge *br, unsigned long val)
1790 {
1791         val = !!val;
1792
1793         spin_lock_bh(&br->multicast_lock);
1794         if (br->multicast_querier == val)
1795                 goto unlock;
1796
1797         br->multicast_querier = val;
1798         if (val)
1799                 br_multicast_start_querier(br);
1800
1801 unlock:
1802         spin_unlock_bh(&br->multicast_lock);
1803
1804         return 0;
1805 }
1806
1807 int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val)
1808 {
1809         int err = -ENOENT;
1810         u32 old;
1811         struct net_bridge_mdb_htable *mdb;
1812
1813         spin_lock(&br->multicast_lock);
1814         if (!netif_running(br->dev))
1815                 goto unlock;
1816
1817         err = -EINVAL;
1818         if (!is_power_of_2(val))
1819                 goto unlock;
1820
1821         mdb = mlock_dereference(br->mdb, br);
1822         if (mdb && val < mdb->size)
1823                 goto unlock;
1824
1825         err = 0;
1826
1827         old = br->hash_max;
1828         br->hash_max = val;
1829
1830         if (mdb) {
1831                 if (mdb->old) {
1832                         err = -EEXIST;
1833 rollback:
1834                         br->hash_max = old;
1835                         goto unlock;
1836                 }
1837
1838                 err = br_mdb_rehash(&br->mdb, br->hash_max,
1839                                     br->hash_elasticity);
1840                 if (err)
1841                         goto rollback;
1842         }
1843
1844 unlock:
1845         spin_unlock(&br->multicast_lock);
1846
1847         return err;
1848 }