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/export.h>
  15 #include <linux/if_ether.h>
  16 #include <linux/igmp.h>
  17 #include <linux/jhash.h>
  18 #include <linux/kernel.h>
  19 #include <linux/log2.h>
  20 #include <linux/netdevice.h>
  21 #include <linux/netfilter_bridge.h>
  22 #include <linux/random.h>
  23 #include <linux/rculist.h>
  24 #include <linux/skbuff.h>
  25 #include <linux/slab.h>
  26 #include <linux/timer.h>
  27 #include <linux/inetdevice.h>
  28 #include <net/ip.h>
  29 #if IS_ENABLED(CONFIG_IPV6)
  30 #include <net/ipv6.h>
  31 #include <net/mld.h>
  32 #include <net/ip6_checksum.h>
  33 #include <net/addrconf.h>
  34 #endif
  35
  36 #include "br_private.h"
  37
  38 static void br_multicast_start_querier(struct net_bridge *br,
  39                                        struct bridge_mcast_own_query *query);
  40 static void br_multicast_add_router(struct net_bridge *br,
  41                                     struct net_bridge_port *port);
  42 static void br_ip4_multicast_leave_group(struct net_bridge *br,
  43                                          struct net_bridge_port *port,
  44                                          __be32 group,
  45                                          __u16 vid);
  46 #if IS_ENABLED(CONFIG_IPV6)
  47 static void br_ip6_multicast_leave_group(struct net_bridge *br,
  48                                          struct net_bridge_port *port,
  49                                          const struct in6_addr *group,
  50                                          __u16 vid);
  51 #endif
  52 unsigned int br_mdb_rehash_seq;
  53
  54 static inline int br_ip_equal(const struct br_ip *a, const struct br_ip *b)
  55 {
  56         if (a->proto != b->proto)
  57                 return 0;
  58         if (a->vid != b->vid)
  59                 return 0;
  60         switch (a->proto) {
  61         case htons(ETH_P_IP):
  62                 return a->u.ip4 == b->u.ip4;
  63 #if IS_ENABLED(CONFIG_IPV6)
  64         case htons(ETH_P_IPV6):
  65                 return ipv6_addr_equal(&a->u.ip6, &b->u.ip6);
  66 #endif
  67         }
  68         return 0;
  69 }
  70
  71 static inline int __br_ip4_hash(struct net_bridge_mdb_htable *mdb, __be32 ip,
  72                                 __u16 vid)
  73 {
  74         return jhash_2words((__force u32)ip, vid, mdb->secret) & (mdb->max - 1);
  75 }
  76
  77 #if IS_ENABLED(CONFIG_IPV6)
  78 static inline int __br_ip6_hash(struct net_bridge_mdb_htable *mdb,
  79                                 const struct in6_addr *ip,
  80                                 __u16 vid)
  81 {
  82         return jhash_2words(ipv6_addr_hash(ip), vid,
  83                             mdb->secret) & (mdb->max - 1);
  84 }
  85 #endif
  86
  87 static inline int br_ip_hash(struct net_bridge_mdb_htable *mdb,
  88                              struct br_ip *ip)
  89 {
  90         switch (ip->proto) {
  91         case htons(ETH_P_IP):
  92                 return __br_ip4_hash(mdb, ip->u.ip4, ip->vid);
  93 #if IS_ENABLED(CONFIG_IPV6)
  94         case htons(ETH_P_IPV6):
  95                 return __br_ip6_hash(mdb, &ip->u.ip6, ip->vid);
  96 #endif
  97         }
  98         return 0;
  99 }
 100
 101 static struct net_bridge_mdb_entry *__br_mdb_ip_get(
 102         struct net_bridge_mdb_htable *mdb, struct br_ip *dst, int hash)
 103 {
 104         struct net_bridge_mdb_entry *mp;
 105
 106         hlist_for_each_entry_rcu(mp, &mdb->mhash[hash], hlist[mdb->ver]) {
 107                 if (br_ip_equal(&mp->addr, dst))
 108                         return mp;
 109         }
 110
 111         return NULL;
 112 }
 113
 114 struct net_bridge_mdb_entry *br_mdb_ip_get(struct net_bridge_mdb_htable *mdb,
 115                                            struct br_ip *dst)
 116 {
 117         if (!mdb)
 118                 return NULL;
 119
 120         return __br_mdb_ip_get(mdb, dst, br_ip_hash(mdb, dst));
 121 }
 122
 123 static struct net_bridge_mdb_entry *br_mdb_ip4_get(
 124         struct net_bridge_mdb_htable *mdb, __be32 dst, __u16 vid)
 125 {
 126         struct br_ip br_dst;
 127
 128         br_dst.u.ip4 = dst;
 129         br_dst.proto = htons(ETH_P_IP);
 130         br_dst.vid = vid;
 131
 132         return br_mdb_ip_get(mdb, &br_dst);
 133 }
 134
 135 #if IS_ENABLED(CONFIG_IPV6)
 136 static struct net_bridge_mdb_entry *br_mdb_ip6_get(
 137         struct net_bridge_mdb_htable *mdb, const struct in6_addr *dst,
 138         __u16 vid)
 139 {
 140         struct br_ip br_dst;
 141
 142         br_dst.u.ip6 = *dst;
 143         br_dst.proto = htons(ETH_P_IPV6);
 144         br_dst.vid = vid;
 145
 146         return br_mdb_ip_get(mdb, &br_dst);
 147 }
 148 #endif
 149
 150 struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br,
 151                                         struct sk_buff *skb, u16 vid)
 152 {
 153         struct net_bridge_mdb_htable *mdb = rcu_dereference(br->mdb);
 154         struct br_ip ip;
 155
 156         if (br->multicast_disabled)
 157                 return NULL;
 158
 159         if (BR_INPUT_SKB_CB(skb)->igmp)
 160                 return NULL;
 161
 162         ip.proto = skb->protocol;
 163         ip.vid = vid;
 164
 165         switch (skb->protocol) {
 166         case htons(ETH_P_IP):
 167                 ip.u.ip4 = ip_hdr(skb)->daddr;
 168                 break;
 169 #if IS_ENABLED(CONFIG_IPV6)
 170         case htons(ETH_P_IPV6):
 171                 ip.u.ip6 = ipv6_hdr(skb)->daddr;
 172                 break;
 173 #endif
 174         default:
 175                 return NULL;
 176         }
 177
 178         return br_mdb_ip_get(mdb, &ip);
 179 }
 180
 181 static void br_mdb_free(struct rcu_head *head)
 182 {
 183         struct net_bridge_mdb_htable *mdb =
 184                 container_of(head, struct net_bridge_mdb_htable, rcu);
 185         struct net_bridge_mdb_htable *old = mdb->old;
 186
 187         mdb->old = NULL;
 188         kfree(old->mhash);
 189         kfree(old);
 190 }
 191
 192 static int br_mdb_copy(struct net_bridge_mdb_htable *new,
 193                        struct net_bridge_mdb_htable *old,
 194                        int elasticity)
 195 {
 196         struct net_bridge_mdb_entry *mp;
 197         int maxlen;
 198         int len;
 199         int i;
 200
 201         for (i = 0; i < old->max; i++)
 202                 hlist_for_each_entry(mp, &old->mhash[i], hlist[old->ver])
 203                         hlist_add_head(&mp->hlist[new->ver],
 204                                        &new->mhash[br_ip_hash(new, &mp->addr)]);
 205
 206         if (!elasticity)
 207                 return 0;
 208
 209         maxlen = 0;
 210         for (i = 0; i < new->max; i++) {
 211                 len = 0;
 212                 hlist_for_each_entry(mp, &new->mhash[i], hlist[new->ver])
 213                         len++;
 214                 if (len > maxlen)
 215                         maxlen = len;
 216         }
 217
 218         return maxlen > elasticity ? -EINVAL : 0;
 219 }
 220
 221 void br_multicast_free_pg(struct rcu_head *head)
 222 {
 223         struct net_bridge_port_group *p =
 224                 container_of(head, struct net_bridge_port_group, rcu);
 225
 226         kfree(p);
 227 }
 228
 229 static void br_multicast_free_group(struct rcu_head *head)
 230 {
 231         struct net_bridge_mdb_entry *mp =
 232                 container_of(head, struct net_bridge_mdb_entry, rcu);
 233
 234         kfree(mp);
 235 }
 236
 237 static void br_multicast_group_expired(unsigned long data)
 238 {
 239         struct net_bridge_mdb_entry *mp = (void *)data;
 240         struct net_bridge *br = mp->br;
 241         struct net_bridge_mdb_htable *mdb;
 242
 243         spin_lock(&br->multicast_lock);
 244         if (!netif_running(br->dev) || timer_pending(&mp->timer))
 245                 goto out;
 246
 247         mp->mglist = false;
 248
 249         if (mp->ports)
 250                 goto out;
 251
 252         mdb = mlock_dereference(br->mdb, br);
 253
 254         hlist_del_rcu(&mp->hlist[mdb->ver]);
 255         mdb->size--;
 256
 257         call_rcu_bh(&mp->rcu, br_multicast_free_group);
 258
 259 out:
 260         spin_unlock(&br->multicast_lock);
 261 }
 262
 263 static void br_multicast_del_pg(struct net_bridge *br,
 264                                 struct net_bridge_port_group *pg)
 265 {
 266         struct net_bridge_mdb_htable *mdb;
 267         struct net_bridge_mdb_entry *mp;
 268         struct net_bridge_port_group *p;
 269         struct net_bridge_port_group __rcu **pp;
 270
 271         mdb = mlock_dereference(br->mdb, br);
 272
 273         mp = br_mdb_ip_get(mdb, &pg->addr);
 274         if (WARN_ON(!mp))
 275                 return;
 276
 277         for (pp = &mp->ports;
 278              (p = mlock_dereference(*pp, br)) != NULL;
 279              pp = &p->next) {
 280                 if (p != pg)
 281                         continue;
 282
 283                 rcu_assign_pointer(*pp, p->next);
 284                 hlist_del_init(&p->mglist);
 285                 del_timer(&p->timer);
 286                 br_mdb_notify(br->dev, p, RTM_DELMDB);
 287                 call_rcu_bh(&p->rcu, br_multicast_free_pg);
 288
 289                 if (!mp->ports && !mp->mglist &&
 290                     netif_running(br->dev))
 291                         mod_timer(&mp->timer, jiffies);
 292
 293                 return;
 294         }
 295
 296         WARN_ON(1);
 297 }
 298
 299 static void br_multicast_port_group_expired(unsigned long data)
 300 {
 301         struct net_bridge_port_group *pg = (void *)data;
 302         struct net_bridge *br = pg->port->br;
 303
 304         spin_lock(&br->multicast_lock);
 305         if (!netif_running(br->dev) || timer_pending(&pg->timer) ||
 306             hlist_unhashed(&pg->mglist) || pg->flags & MDB_PG_FLAGS_PERMANENT)
 307                 goto out;
 308
 309         br_multicast_del_pg(br, pg);
 310
 311 out:
 312         spin_unlock(&br->multicast_lock);
 313 }
 314
 315 static int br_mdb_rehash(struct net_bridge_mdb_htable __rcu **mdbp, int max,
 316                          int elasticity)
 317 {
 318         struct net_bridge_mdb_htable *old = rcu_dereference_protected(*mdbp, 1);
 319         struct net_bridge_mdb_htable *mdb;
 320         int err;
 321
 322         mdb = kmalloc(sizeof(*mdb), GFP_ATOMIC);
 323         if (!mdb)
 324                 return -ENOMEM;
 325
 326         mdb->max = max;
 327         mdb->old = old;
 328
 329         mdb->mhash = kzalloc(max * sizeof(*mdb->mhash), GFP_ATOMIC);
 330         if (!mdb->mhash) {
 331                 kfree(mdb);
 332                 return -ENOMEM;
 333         }
 334
 335         mdb->size = old ? old->size : 0;
 336         mdb->ver = old ? old->ver ^ 1 : 0;
 337
 338         if (!old || elasticity)
 339                 get_random_bytes(&mdb->secret, sizeof(mdb->secret));
 340         else
 341                 mdb->secret = old->secret;
 342
 343         if (!old)
 344                 goto out;
 345
 346         err = br_mdb_copy(mdb, old, elasticity);
 347         if (err) {
 348                 kfree(mdb->mhash);
 349                 kfree(mdb);
 350                 return err;
 351         }
 352
 353         br_mdb_rehash_seq++;
 354         call_rcu_bh(&mdb->rcu, br_mdb_free);
 355
 356 out:
 357         rcu_assign_pointer(*mdbp, mdb);
 358
 359         return 0;
 360 }
 361
 362 static struct sk_buff *br_ip4_multicast_alloc_query(struct net_bridge *br,
 363                                                     __be32 group)
 364 {
 365         struct sk_buff *skb;
 366         struct igmphdr *ih;
 367         struct ethhdr *eth;
 368         struct iphdr *iph;
 369
 370         skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*iph) +
 371                                                  sizeof(*ih) + 4);
 372         if (!skb)
 373                 goto out;
 374
 375         skb->protocol = htons(ETH_P_IP);
 376
 377         skb_reset_mac_header(skb);
 378         eth = eth_hdr(skb);
 379
 380         ether_addr_copy(eth->h_source, br->dev->dev_addr);
 381         eth->h_dest[0] = 1;
 382         eth->h_dest[1] = 0;
 383         eth->h_dest[2] = 0x5e;
 384         eth->h_dest[3] = 0;
 385         eth->h_dest[4] = 0;
 386         eth->h_dest[5] = 1;
 387         eth->h_proto = htons(ETH_P_IP);
 388         skb_put(skb, sizeof(*eth));
 389
 390         skb_set_network_header(skb, skb->len);
 391         iph = ip_hdr(skb);
 392
 393         iph->version = 4;
 394         iph->ihl = 6;
 395         iph->tos = 0xc0;
 396         iph->tot_len = htons(sizeof(*iph) + sizeof(*ih) + 4);
 397         iph->id = 0;
 398         iph->frag_off = htons(IP_DF);
 399         iph->ttl = 1;
 400         iph->protocol = IPPROTO_IGMP;
 401         iph->saddr = br->multicast_query_use_ifaddr ?
 402                      inet_select_addr(br->dev, 0, RT_SCOPE_LINK) : 0;
 403         iph->daddr = htonl(INADDR_ALLHOSTS_GROUP);
 404         ((u8 *)&iph[1])[0] = IPOPT_RA;
 405         ((u8 *)&iph[1])[1] = 4;
 406         ((u8 *)&iph[1])[2] = 0;
 407         ((u8 *)&iph[1])[3] = 0;
 408         ip_send_check(iph);
 409         skb_put(skb, 24);
 410
 411         skb_set_transport_header(skb, skb->len);
 412         ih = igmp_hdr(skb);
 413         ih->type = IGMP_HOST_MEMBERSHIP_QUERY;
 414         ih->code = (group ? br->multicast_last_member_interval :
 415                             br->multicast_query_response_interval) /
 416                    (HZ / IGMP_TIMER_SCALE);
 417         ih->group = group;
 418         ih->csum = 0;
 419         ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
 420         skb_put(skb, sizeof(*ih));
 421
 422         __skb_pull(skb, sizeof(*eth));
 423
 424 out:
 425         return skb;
 426 }
 427
 428 #if IS_ENABLED(CONFIG_IPV6)
 429 static struct sk_buff *br_ip6_multicast_alloc_query(struct net_bridge *br,
 430                                                     const struct in6_addr *group)
 431 {
 432         struct sk_buff *skb;
 433         struct ipv6hdr *ip6h;
 434         struct mld_msg *mldq;
 435         struct ethhdr *eth;
 436         u8 *hopopt;
 437         unsigned long interval;
 438
 439         skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*ip6h) +
 440                                                  8 + sizeof(*mldq));
 441         if (!skb)
 442                 goto out;
 443
 444         skb->protocol = htons(ETH_P_IPV6);
 445
 446         /* Ethernet header */
 447         skb_reset_mac_header(skb);
 448         eth = eth_hdr(skb);
 449
 450         ether_addr_copy(eth->h_source, br->dev->dev_addr);
 451         eth->h_proto = htons(ETH_P_IPV6);
 452         skb_put(skb, sizeof(*eth));
 453
 454         /* IPv6 header + HbH option */
 455         skb_set_network_header(skb, skb->len);
 456         ip6h = ipv6_hdr(skb);
 457
 458         *(__force __be32 *)ip6h = htonl(0x60000000);
 459         ip6h->payload_len = htons(8 + sizeof(*mldq));
 460         ip6h->nexthdr = IPPROTO_HOPOPTS;
 461         ip6h->hop_limit = 1;
 462         ipv6_addr_set(&ip6h->daddr, htonl(0xff020000), 0, 0, htonl(1));
 463         if (ipv6_dev_get_saddr(dev_net(br->dev), br->dev, &ip6h->daddr, 0,
 464                                &ip6h->saddr)) {
 465                 kfree_skb(skb);
 466                 return NULL;
 467         }
 468         ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest);
 469
 470         hopopt = (u8 *)(ip6h + 1);
 471         hopopt[0] = IPPROTO_ICMPV6;             /* next hdr */
 472         hopopt[1] = 0;                          /* length of HbH */
 473         hopopt[2] = IPV6_TLV_ROUTERALERT;       /* Router Alert */
 474         hopopt[3] = 2;                          /* Length of RA Option */
 475         hopopt[4] = 0;                          /* Type = 0x0000 (MLD) */
 476         hopopt[5] = 0;
 477         hopopt[6] = IPV6_TLV_PAD1;              /* Pad1 */
 478         hopopt[7] = IPV6_TLV_PAD1;              /* Pad1 */
 479
 480         skb_put(skb, sizeof(*ip6h) + 8);
 481
 482         /* ICMPv6 */
 483         skb_set_transport_header(skb, skb->len);
 484         mldq = (struct mld_msg *) icmp6_hdr(skb);
 485
 486         interval = ipv6_addr_any(group) ?
 487                         br->multicast_query_response_interval :
 488                         br->multicast_last_member_interval;
 489
 490         mldq->mld_type = ICMPV6_MGM_QUERY;
 491         mldq->mld_code = 0;
 492         mldq->mld_cksum = 0;
 493         mldq->mld_maxdelay = htons((u16)jiffies_to_msecs(interval));
 494         mldq->mld_reserved = 0;
 495         mldq->mld_mca = *group;
 496
 497         /* checksum */
 498         mldq->mld_cksum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
 499                                           sizeof(*mldq), IPPROTO_ICMPV6,
 500                                           csum_partial(mldq,
 501                                                        sizeof(*mldq), 0));
 502         skb_put(skb, sizeof(*mldq));
 503
 504         __skb_pull(skb, sizeof(*eth));
 505
 506 out:
 507         return skb;
 508 }
 509 #endif
 510
 511 static struct sk_buff *br_multicast_alloc_query(struct net_bridge *br,
 512                                                 struct br_ip *addr)
 513 {
 514         switch (addr->proto) {
 515         case htons(ETH_P_IP):
 516                 return br_ip4_multicast_alloc_query(br, addr->u.ip4);
 517 #if IS_ENABLED(CONFIG_IPV6)
 518         case htons(ETH_P_IPV6):
 519                 return br_ip6_multicast_alloc_query(br, &addr->u.ip6);
 520 #endif
 521         }
 522         return NULL;
 523 }
 524
 525 static struct net_bridge_mdb_entry *br_multicast_get_group(
 526         struct net_bridge *br, struct net_bridge_port *port,
 527         struct br_ip *group, int hash)
 528 {
 529         struct net_bridge_mdb_htable *mdb;
 530         struct net_bridge_mdb_entry *mp;
 531         unsigned int count = 0;
 532         unsigned int max;
 533         int elasticity;
 534         int err;
 535
 536         mdb = rcu_dereference_protected(br->mdb, 1);
 537         hlist_for_each_entry(mp, &mdb->mhash[hash], hlist[mdb->ver]) {
 538                 count++;
 539                 if (unlikely(br_ip_equal(group, &mp->addr)))
 540                         return mp;
 541         }
 542
 543         elasticity = 0;
 544         max = mdb->max;
 545
 546         if (unlikely(count > br->hash_elasticity && count)) {
 547                 if (net_ratelimit())
 548                         br_info(br, "Multicast hash table "
 549                                 "chain limit reached: %s\n",
 550                                 port ? port->dev->name : br->dev->name);
 551
 552                 elasticity = br->hash_elasticity;
 553         }
 554
 555         if (mdb->size >= max) {
 556                 max *= 2;
 557                 if (unlikely(max > br->hash_max)) {
 558                         br_warn(br, "Multicast hash table maximum of %d "
 559                                 "reached, disabling snooping: %s\n",
 560                                 br->hash_max,
 561                                 port ? port->dev->name : br->dev->name);
 562                         err = -E2BIG;
 563 disable:
 564                         br->multicast_disabled = 1;
 565                         goto err;
 566                 }
 567         }
 568
 569         if (max > mdb->max || elasticity) {
 570                 if (mdb->old) {
 571                         if (net_ratelimit())
 572                                 br_info(br, "Multicast hash table "
 573                                         "on fire: %s\n",
 574                                         port ? port->dev->name : br->dev->name);
 575                         err = -EEXIST;
 576                         goto err;
 577                 }
 578
 579                 err = br_mdb_rehash(&br->mdb, max, elasticity);
 580                 if (err) {
 581                         br_warn(br, "Cannot rehash multicast "
 582                                 "hash table, disabling snooping: %s, %d, %d\n",
 583                                 port ? port->dev->name : br->dev->name,
 584                                 mdb->size, err);
 585                         goto disable;
 586                 }
 587
 588                 err = -EAGAIN;
 589                 goto err;
 590         }
 591
 592         return NULL;
 593
 594 err:
 595         mp = ERR_PTR(err);
 596         return mp;
 597 }
 598
 599 struct net_bridge_mdb_entry *br_multicast_new_group(struct net_bridge *br,
 600         struct net_bridge_port *port, struct br_ip *group)
 601 {
 602         struct net_bridge_mdb_htable *mdb;
 603         struct net_bridge_mdb_entry *mp;
 604         int hash;
 605         int err;
 606
 607         mdb = rcu_dereference_protected(br->mdb, 1);
 608         if (!mdb) {
 609                 err = br_mdb_rehash(&br->mdb, BR_HASH_SIZE, 0);
 610                 if (err)
 611                         return ERR_PTR(err);
 612                 goto rehash;
 613         }
 614
 615         hash = br_ip_hash(mdb, group);
 616         mp = br_multicast_get_group(br, port, group, hash);
 617         switch (PTR_ERR(mp)) {
 618         case 0:
 619                 break;
 620
 621         case -EAGAIN:
 622 rehash:
 623                 mdb = rcu_dereference_protected(br->mdb, 1);
 624                 hash = br_ip_hash(mdb, group);
 625                 break;
 626
 627         default:
 628                 goto out;
 629         }
 630
 631         mp = kzalloc(sizeof(*mp), GFP_ATOMIC);
 632         if (unlikely(!mp))
 633                 return ERR_PTR(-ENOMEM);
 634
 635         mp->br = br;
 636         mp->addr = *group;
 637         setup_timer(&mp->timer, br_multicast_group_expired,
 638                     (unsigned long)mp);
 639
 640         hlist_add_head_rcu(&mp->hlist[mdb->ver], &mdb->mhash[hash]);
 641         mdb->size++;
 642
 643 out:
 644         return mp;
 645 }
 646
 647 struct net_bridge_port_group *br_multicast_new_port_group(
 648                         struct net_bridge_port *port,
 649                         struct br_ip *group,
 650                         struct net_bridge_port_group __rcu *next,
 651                         unsigned char flags)
 652 {
 653         struct net_bridge_port_group *p;
 654
 655         p = kzalloc(sizeof(*p), GFP_ATOMIC);
 656         if (unlikely(!p))
 657                 return NULL;
 658
 659         p->addr = *group;
 660         p->port = port;
 661         p->flags = flags;
 662         rcu_assign_pointer(p->next, next);
 663         hlist_add_head(&p->mglist, &port->mglist);
 664         setup_timer(&p->timer, br_multicast_port_group_expired,
 665                     (unsigned long)p);
 666         return p;
 667 }
 668
 669 static int br_multicast_add_group(struct net_bridge *br,
 670                                   struct net_bridge_port *port,
 671                                   struct br_ip *group)
 672 {
 673         struct net_bridge_mdb_entry *mp;
 674         struct net_bridge_port_group *p;
 675         struct net_bridge_port_group __rcu **pp;
 676         unsigned long now = jiffies;
 677         int err;
 678
 679         spin_lock(&br->multicast_lock);
 680         if (!netif_running(br->dev) ||
 681             (port && port->state == BR_STATE_DISABLED))
 682                 goto out;
 683
 684         mp = br_multicast_new_group(br, port, group);
 685         err = PTR_ERR(mp);
 686         if (IS_ERR(mp))
 687                 goto err;
 688
 689         if (!port) {
 690                 mp->mglist = true;
 691                 mod_timer(&mp->timer, now + br->multicast_membership_interval);
 692                 goto out;
 693         }
 694
 695         for (pp = &mp->ports;
 696              (p = mlock_dereference(*pp, br)) != NULL;
 697              pp = &p->next) {
 698                 if (p->port == port)
 699                         goto found;
 700                 if ((unsigned long)p->port < (unsigned long)port)
 701                         break;
 702         }
 703
 704         p = br_multicast_new_port_group(port, group, *pp, 0);
 705         if (unlikely(!p))
 706                 goto err;
 707         rcu_assign_pointer(*pp, p);
 708         br_mdb_notify(br->dev, p, RTM_NEWMDB);
 709
 710 found:
 711         mod_timer(&p->timer, now + br->multicast_membership_interval);
 712 out:
 713         err = 0;
 714
 715 err:
 716         spin_unlock(&br->multicast_lock);
 717         return err;
 718 }
 719
 720 static int br_ip4_multicast_add_group(struct net_bridge *br,
 721                                       struct net_bridge_port *port,
 722                                       __be32 group,
 723                                       __u16 vid)
 724 {
 725         struct br_ip br_group;
 726
 727         if (ipv4_is_local_multicast(group))
 728                 return 0;
 729
 730         br_group.u.ip4 = group;
 731         br_group.proto = htons(ETH_P_IP);
 732         br_group.vid = vid;
 733
 734         return br_multicast_add_group(br, port, &br_group);
 735 }
 736
 737 #if IS_ENABLED(CONFIG_IPV6)
 738 static int br_ip6_multicast_add_group(struct net_bridge *br,
 739                                       struct net_bridge_port *port,
 740                                       const struct in6_addr *group,
 741                                       __u16 vid)
 742 {
 743         struct br_ip br_group;
 744
 745         if (ipv6_addr_is_ll_all_nodes(group))
 746                 return 0;
 747
 748         br_group.u.ip6 = *group;
 749         br_group.proto = htons(ETH_P_IPV6);
 750         br_group.vid = vid;
 751
 752         return br_multicast_add_group(br, port, &br_group);
 753 }
 754 #endif
 755
 756 static void br_multicast_router_expired(unsigned long data)
 757 {
 758         struct net_bridge_port *port = (void *)data;
 759         struct net_bridge *br = port->br;
 760
 761         spin_lock(&br->multicast_lock);
 762         if (port->multicast_router == MDB_RTR_TYPE_DISABLED ||
 763             port->multicast_router == MDB_RTR_TYPE_PERM ||
 764             timer_pending(&port->multicast_router_timer) ||
 765             hlist_unhashed(&port->rlist))
 766                 goto out;
 767
 768         hlist_del_init_rcu(&port->rlist);
 769         br_rtr_notify(br->dev, port, RTM_DELMDB);
 770         /* Don't allow timer refresh if the router expired */
 771         if (port->multicast_router == MDB_RTR_TYPE_TEMP)
 772                 port->multicast_router = MDB_RTR_TYPE_TEMP_QUERY;
 773
 774 out:
 775         spin_unlock(&br->multicast_lock);
 776 }
 777
 778 static void br_multicast_local_router_expired(unsigned long data)
 779 {
 780 }
 781
 782 static void br_multicast_querier_expired(struct net_bridge *br,
 783                                          struct bridge_mcast_own_query *query)
 784 {
 785         spin_lock(&br->multicast_lock);
 786         if (!netif_running(br->dev) || br->multicast_disabled)
 787                 goto out;
 788
 789         br_multicast_start_querier(br, query);
 790
 791 out:
 792         spin_unlock(&br->multicast_lock);
 793 }
 794
 795 static void br_ip4_multicast_querier_expired(unsigned long data)
 796 {
 797         struct net_bridge *br = (void *)data;
 798
 799         br_multicast_querier_expired(br, &br->ip4_own_query);
 800 }
 801
 802 #if IS_ENABLED(CONFIG_IPV6)
 803 static void br_ip6_multicast_querier_expired(unsigned long data)
 804 {
 805         struct net_bridge *br = (void *)data;
 806
 807         br_multicast_querier_expired(br, &br->ip6_own_query);
 808 }
 809 #endif
 810
 811 static void br_multicast_select_own_querier(struct net_bridge *br,
 812                                             struct br_ip *ip,
 813                                             struct sk_buff *skb)
 814 {
 815         if (ip->proto == htons(ETH_P_IP))
 816                 br->ip4_querier.addr.u.ip4 = ip_hdr(skb)->saddr;
 817 #if IS_ENABLED(CONFIG_IPV6)
 818         else
 819                 br->ip6_querier.addr.u.ip6 = ipv6_hdr(skb)->saddr;
 820 #endif
 821 }
 822
 823 static void __br_multicast_send_query(struct net_bridge *br,
 824                                       struct net_bridge_port *port,
 825                                       struct br_ip *ip)
 826 {
 827         struct sk_buff *skb;
 828
 829         skb = br_multicast_alloc_query(br, ip);
 830         if (!skb)
 831                 return;
 832
 833         if (port) {
 834                 skb->dev = port->dev;
 835                 NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT,
 836                         dev_net(port->dev), NULL, skb, NULL, skb->dev,
 837                         br_dev_queue_push_xmit);
 838         } else {
 839                 br_multicast_select_own_querier(br, ip, skb);
 840                 netif_rx(skb);
 841         }
 842 }
 843
 844 static void br_multicast_send_query(struct net_bridge *br,
 845                                     struct net_bridge_port *port,
 846                                     struct bridge_mcast_own_query *own_query)
 847 {
 848         unsigned long time;
 849         struct br_ip br_group;
 850         struct bridge_mcast_other_query *other_query = NULL;
 851
 852         if (!netif_running(br->dev) || br->multicast_disabled ||
 853             !br->multicast_querier)
 854                 return;
 855
 856         memset(&br_group.u, 0, sizeof(br_group.u));
 857
 858         if (port ? (own_query == &port->ip4_own_query) :
 859                    (own_query == &br->ip4_own_query)) {
 860                 other_query = &br->ip4_other_query;
 861                 br_group.proto = htons(ETH_P_IP);
 862 #if IS_ENABLED(CONFIG_IPV6)
 863         } else {
 864                 other_query = &br->ip6_other_query;
 865                 br_group.proto = htons(ETH_P_IPV6);
 866 #endif
 867         }
 868
 869         if (!other_query || timer_pending(&other_query->timer))
 870                 return;
 871
 872         __br_multicast_send_query(br, port, &br_group);
 873
 874         time = jiffies;
 875         time += own_query->startup_sent < br->multicast_startup_query_count ?
 876                 br->multicast_startup_query_interval :
 877                 br->multicast_query_interval;
 878         mod_timer(&own_query->timer, time);
 879 }
 880
 881 static void
 882 br_multicast_port_query_expired(struct net_bridge_port *port,
 883                                 struct bridge_mcast_own_query *query)
 884 {
 885         struct net_bridge *br = port->br;
 886
 887         spin_lock(&br->multicast_lock);
 888         if (port->state == BR_STATE_DISABLED ||
 889             port->state == BR_STATE_BLOCKING)
 890                 goto out;
 891
 892         if (query->startup_sent < br->multicast_startup_query_count)
 893                 query->startup_sent++;
 894
 895         br_multicast_send_query(port->br, port, query);
 896
 897 out:
 898         spin_unlock(&br->multicast_lock);
 899 }
 900
 901 static void br_ip4_multicast_port_query_expired(unsigned long data)
 902 {
 903         struct net_bridge_port *port = (void *)data;
 904
 905         br_multicast_port_query_expired(port, &port->ip4_own_query);
 906 }
 907
 908 #if IS_ENABLED(CONFIG_IPV6)
 909 static void br_ip6_multicast_port_query_expired(unsigned long data)
 910 {
 911         struct net_bridge_port *port = (void *)data;
 912
 913         br_multicast_port_query_expired(port, &port->ip6_own_query);
 914 }
 915 #endif
 916
 917 void br_multicast_add_port(struct net_bridge_port *port)
 918 {
 919         port->multicast_router = MDB_RTR_TYPE_TEMP_QUERY;
 920
 921         setup_timer(&port->multicast_router_timer, br_multicast_router_expired,
 922                     (unsigned long)port);
 923         setup_timer(&port->ip4_own_query.timer,
 924                     br_ip4_multicast_port_query_expired, (unsigned long)port);
 925 #if IS_ENABLED(CONFIG_IPV6)
 926         setup_timer(&port->ip6_own_query.timer,
 927                     br_ip6_multicast_port_query_expired, (unsigned long)port);
 928 #endif
 929 }
 930
 931 void br_multicast_del_port(struct net_bridge_port *port)
 932 {
 933         struct net_bridge *br = port->br;
 934         struct net_bridge_port_group *pg;
 935         struct hlist_node *n;
 936
 937         /* Take care of the remaining groups, only perm ones should be left */
 938         spin_lock_bh(&br->multicast_lock);
 939         hlist_for_each_entry_safe(pg, n, &port->mglist, mglist)
 940                 br_multicast_del_pg(br, pg);
 941         spin_unlock_bh(&br->multicast_lock);
 942         del_timer_sync(&port->multicast_router_timer);
 943 }
 944
 945 static void br_multicast_enable(struct bridge_mcast_own_query *query)
 946 {
 947         query->startup_sent = 0;
 948
 949         if (try_to_del_timer_sync(&query->timer) >= 0 ||
 950             del_timer(&query->timer))
 951                 mod_timer(&query->timer, jiffies);
 952 }
 953
 954 void br_multicast_enable_port(struct net_bridge_port *port)
 955 {
 956         struct net_bridge *br = port->br;
 957
 958         spin_lock(&br->multicast_lock);
 959         if (br->multicast_disabled || !netif_running(br->dev))
 960                 goto out;
 961
 962         br_multicast_enable(&port->ip4_own_query);
 963 #if IS_ENABLED(CONFIG_IPV6)
 964         br_multicast_enable(&port->ip6_own_query);
 965 #endif
 966         if (port->multicast_router == MDB_RTR_TYPE_PERM &&
 967             hlist_unhashed(&port->rlist))
 968                 br_multicast_add_router(br, port);
 969
 970 out:
 971         spin_unlock(&br->multicast_lock);
 972 }
 973
 974 void br_multicast_disable_port(struct net_bridge_port *port)
 975 {
 976         struct net_bridge *br = port->br;
 977         struct net_bridge_port_group *pg;
 978         struct hlist_node *n;
 979
 980         spin_lock(&br->multicast_lock);
 981         hlist_for_each_entry_safe(pg, n, &port->mglist, mglist)
 982                 if (!(pg->flags & MDB_PG_FLAGS_PERMANENT))
 983                         br_multicast_del_pg(br, pg);
 984
 985         if (!hlist_unhashed(&port->rlist)) {
 986                 hlist_del_init_rcu(&port->rlist);
 987                 br_rtr_notify(br->dev, port, RTM_DELMDB);
 988                 /* Don't allow timer refresh if disabling */
 989                 if (port->multicast_router == MDB_RTR_TYPE_TEMP)
 990                         port->multicast_router = MDB_RTR_TYPE_TEMP_QUERY;
 991         }
 992         del_timer(&port->multicast_router_timer);
 993         del_timer(&port->ip4_own_query.timer);
 994 #if IS_ENABLED(CONFIG_IPV6)
 995         del_timer(&port->ip6_own_query.timer);
 996 #endif
 997         spin_unlock(&br->multicast_lock);
 998 }
 999
1000 static int br_ip4_multicast_igmp3_report(struct net_bridge *br,
1001                                          struct net_bridge_port *port,
1002                                          struct sk_buff *skb,
1003                                          u16 vid)
1004 {
1005         struct igmpv3_report *ih;
1006         struct igmpv3_grec *grec;
1007         int i;
1008         int len;
1009         int num;
1010         int type;
1011         int err = 0;
1012         __be32 group;
1013
1014         ih = igmpv3_report_hdr(skb);
1015         num = ntohs(ih->ngrec);
1016         len = skb_transport_offset(skb) + sizeof(*ih);
1017
1018         for (i = 0; i < num; i++) {
1019                 len += sizeof(*grec);
1020                 if (!pskb_may_pull(skb, len))
1021                         return -EINVAL;
1022
1023                 grec = (void *)(skb->data + len - sizeof(*grec));
1024                 group = grec->grec_mca;
1025                 type = grec->grec_type;
1026
1027                 len += ntohs(grec->grec_nsrcs) * 4;
1028                 if (!pskb_may_pull(skb, len))
1029                         return -EINVAL;
1030
1031                 /* We treat this as an IGMPv2 report for now. */
1032                 switch (type) {
1033                 case IGMPV3_MODE_IS_INCLUDE:
1034                 case IGMPV3_MODE_IS_EXCLUDE:
1035                 case IGMPV3_CHANGE_TO_INCLUDE:
1036                 case IGMPV3_CHANGE_TO_EXCLUDE:
1037                 case IGMPV3_ALLOW_NEW_SOURCES:
1038                 case IGMPV3_BLOCK_OLD_SOURCES:
1039                         break;
1040
1041                 default:
1042                         continue;
1043                 }
1044
1045                 if ((type == IGMPV3_CHANGE_TO_INCLUDE ||
1046                      type == IGMPV3_MODE_IS_INCLUDE) &&
1047                     ntohs(grec->grec_nsrcs) == 0) {
1048                         br_ip4_multicast_leave_group(br, port, group, vid);
1049                 } else {
1050                         err = br_ip4_multicast_add_group(br, port, group, vid);
1051                         if (err)
1052                                 break;
1053                 }
1054         }
1055
1056         return err;
1057 }
1058
1059 #if IS_ENABLED(CONFIG_IPV6)
1060 static int br_ip6_multicast_mld2_report(struct net_bridge *br,
1061                                         struct net_bridge_port *port,
1062                                         struct sk_buff *skb,
1063                                         u16 vid)
1064 {
1065         struct icmp6hdr *icmp6h;
1066         struct mld2_grec *grec;
1067         int i;
1068         int len;
1069         int num;
1070         int err = 0;
1071
1072         if (!pskb_may_pull(skb, sizeof(*icmp6h)))
1073                 return -EINVAL;
1074
1075         icmp6h = icmp6_hdr(skb);
1076         num = ntohs(icmp6h->icmp6_dataun.un_data16[1]);
1077         len = skb_transport_offset(skb) + sizeof(*icmp6h);
1078
1079         for (i = 0; i < num; i++) {
1080                 __be16 *nsrcs, _nsrcs;
1081
1082                 nsrcs = skb_header_pointer(skb,
1083                                            len + offsetof(struct mld2_grec,
1084                                                           grec_nsrcs),
1085                                            sizeof(_nsrcs), &_nsrcs);
1086                 if (!nsrcs)
1087                         return -EINVAL;
1088
1089                 if (!pskb_may_pull(skb,
1090                                    len + sizeof(*grec) +
1091                                    sizeof(struct in6_addr) * ntohs(*nsrcs)))
1092                         return -EINVAL;
1093
1094                 grec = (struct mld2_grec *)(skb->data + len);
1095                 len += sizeof(*grec) +
1096                        sizeof(struct in6_addr) * ntohs(*nsrcs);
1097
1098                 /* We treat these as MLDv1 reports for now. */
1099                 switch (grec->grec_type) {
1100                 case MLD2_MODE_IS_INCLUDE:
1101                 case MLD2_MODE_IS_EXCLUDE:
1102                 case MLD2_CHANGE_TO_INCLUDE:
1103                 case MLD2_CHANGE_TO_EXCLUDE:
1104                 case MLD2_ALLOW_NEW_SOURCES:
1105                 case MLD2_BLOCK_OLD_SOURCES:
1106                         break;
1107
1108                 default:
1109                         continue;
1110                 }
1111
1112                 if ((grec->grec_type == MLD2_CHANGE_TO_INCLUDE ||
1113                      grec->grec_type == MLD2_MODE_IS_INCLUDE) &&
1114                     ntohs(*nsrcs) == 0) {
1115                         br_ip6_multicast_leave_group(br, port, &grec->grec_mca,
1116                                                      vid);
1117                 } else {
1118                         err = br_ip6_multicast_add_group(br, port,
1119                                                          &grec->grec_mca, vid);
1120                         if (!err)
1121                                 break;
1122                 }
1123         }
1124
1125         return err;
1126 }
1127 #endif
1128
1129 static bool br_ip4_multicast_select_querier(struct net_bridge *br,
1130                                             struct net_bridge_port *port,
1131                                             __be32 saddr)
1132 {
1133         if (!timer_pending(&br->ip4_own_query.timer) &&
1134             !timer_pending(&br->ip4_other_query.timer))
1135                 goto update;
1136
1137         if (!br->ip4_querier.addr.u.ip4)
1138                 goto update;
1139
1140         if (ntohl(saddr) <= ntohl(br->ip4_querier.addr.u.ip4))
1141                 goto update;
1142
1143         return false;
1144
1145 update:
1146         br->ip4_querier.addr.u.ip4 = saddr;
1147
1148         /* update protected by general multicast_lock by caller */
1149         rcu_assign_pointer(br->ip4_querier.port, port);
1150
1151         return true;
1152 }
1153
1154 #if IS_ENABLED(CONFIG_IPV6)
1155 static bool br_ip6_multicast_select_querier(struct net_bridge *br,
1156                                             struct net_bridge_port *port,
1157                                             struct in6_addr *saddr)
1158 {
1159         if (!timer_pending(&br->ip6_own_query.timer) &&
1160             !timer_pending(&br->ip6_other_query.timer))
1161                 goto update;
1162
1163         if (ipv6_addr_cmp(saddr, &br->ip6_querier.addr.u.ip6) <= 0)
1164                 goto update;
1165
1166         return false;
1167
1168 update:
1169         br->ip6_querier.addr.u.ip6 = *saddr;
1170
1171         /* update protected by general multicast_lock by caller */
1172         rcu_assign_pointer(br->ip6_querier.port, port);
1173
1174         return true;
1175 }
1176 #endif
1177
1178 static bool br_multicast_select_querier(struct net_bridge *br,
1179                                         struct net_bridge_port *port,
1180                                         struct br_ip *saddr)
1181 {
1182         switch (saddr->proto) {
1183         case htons(ETH_P_IP):
1184                 return br_ip4_multicast_select_querier(br, port, saddr->u.ip4);
1185 #if IS_ENABLED(CONFIG_IPV6)
1186         case htons(ETH_P_IPV6):
1187                 return br_ip6_multicast_select_querier(br, port, &saddr->u.ip6);
1188 #endif
1189         }
1190
1191         return false;
1192 }
1193
1194 static void
1195 br_multicast_update_query_timer(struct net_bridge *br,
1196                                 struct bridge_mcast_other_query *query,
1197                                 unsigned long max_delay)
1198 {
1199         if (!timer_pending(&query->timer))
1200                 query->delay_time = jiffies + max_delay;
1201
1202         mod_timer(&query->timer, jiffies + br->multicast_querier_interval);
1203 }
1204
1205 /*
1206  * Add port to router_list
1207  *  list is maintained ordered by pointer value
1208  *  and locked by br->multicast_lock and RCU
1209  */
1210 static void br_multicast_add_router(struct net_bridge *br,
1211                                     struct net_bridge_port *port)
1212 {
1213         struct net_bridge_port *p;
1214         struct hlist_node *slot = NULL;
1215
1216         if (!hlist_unhashed(&port->rlist))
1217                 return;
1218
1219         hlist_for_each_entry(p, &br->router_list, rlist) {
1220                 if ((unsigned long) port >= (unsigned long) p)
1221                         break;
1222                 slot = &p->rlist;
1223         }
1224
1225         if (slot)
1226                 hlist_add_behind_rcu(&port->rlist, slot);
1227         else
1228                 hlist_add_head_rcu(&port->rlist, &br->router_list);
1229         br_rtr_notify(br->dev, port, RTM_NEWMDB);
1230 }
1231
1232 static void br_multicast_mark_router(struct net_bridge *br,
1233                                      struct net_bridge_port *port)
1234 {
1235         unsigned long now = jiffies;
1236
1237         if (!port) {
1238                 if (br->multicast_router == MDB_RTR_TYPE_TEMP_QUERY)
1239                         mod_timer(&br->multicast_router_timer,
1240                                   now + br->multicast_querier_interval);
1241                 return;
1242         }
1243
1244         if (port->multicast_router == MDB_RTR_TYPE_DISABLED ||
1245             port->multicast_router == MDB_RTR_TYPE_PERM)
1246                 return;
1247
1248         br_multicast_add_router(br, port);
1249
1250         mod_timer(&port->multicast_router_timer,
1251                   now + br->multicast_querier_interval);
1252 }
1253
1254 static void br_multicast_query_received(struct net_bridge *br,
1255                                         struct net_bridge_port *port,
1256                                         struct bridge_mcast_other_query *query,
1257                                         struct br_ip *saddr,
1258                                         unsigned long max_delay)
1259 {
1260         if (!br_multicast_select_querier(br, port, saddr))
1261                 return;
1262
1263         br_multicast_update_query_timer(br, query, max_delay);
1264         br_multicast_mark_router(br, port);
1265 }
1266
1267 static int br_ip4_multicast_query(struct net_bridge *br,
1268                                   struct net_bridge_port *port,
1269                                   struct sk_buff *skb,
1270                                   u16 vid)
1271 {
1272         const struct iphdr *iph = ip_hdr(skb);
1273         struct igmphdr *ih = igmp_hdr(skb);
1274         struct net_bridge_mdb_entry *mp;
1275         struct igmpv3_query *ih3;
1276         struct net_bridge_port_group *p;
1277         struct net_bridge_port_group __rcu **pp;
1278         struct br_ip saddr;
1279         unsigned long max_delay;
1280         unsigned long now = jiffies;
1281         __be32 group;
1282         int err = 0;
1283
1284         spin_lock(&br->multicast_lock);
1285         if (!netif_running(br->dev) ||
1286             (port && port->state == BR_STATE_DISABLED))
1287                 goto out;
1288
1289         group = ih->group;
1290
1291         if (skb->len == sizeof(*ih)) {
1292                 max_delay = ih->code * (HZ / IGMP_TIMER_SCALE);
1293
1294                 if (!max_delay) {
1295                         max_delay = 10 * HZ;
1296                         group = 0;
1297                 }
1298         } else if (skb->len >= sizeof(*ih3)) {
1299                 ih3 = igmpv3_query_hdr(skb);
1300                 if (ih3->nsrcs)
1301                         goto out;
1302
1303                 max_delay = ih3->code ?
1304                             IGMPV3_MRC(ih3->code) * (HZ / IGMP_TIMER_SCALE) : 1;
1305         } else {
1306                 goto out;
1307         }
1308
1309         if (!group) {
1310                 saddr.proto = htons(ETH_P_IP);
1311                 saddr.u.ip4 = iph->saddr;
1312
1313                 br_multicast_query_received(br, port, &br->ip4_other_query,
1314                                             &saddr, max_delay);
1315                 goto out;
1316         }
1317
1318         mp = br_mdb_ip4_get(mlock_dereference(br->mdb, br), group, vid);
1319         if (!mp)
1320                 goto out;
1321
1322         max_delay *= br->multicast_last_member_count;
1323
1324         if (mp->mglist &&
1325             (timer_pending(&mp->timer) ?
1326              time_after(mp->timer.expires, now + max_delay) :
1327              try_to_del_timer_sync(&mp->timer) >= 0))
1328                 mod_timer(&mp->timer, now + max_delay);
1329
1330         for (pp = &mp->ports;
1331              (p = mlock_dereference(*pp, br)) != NULL;
1332              pp = &p->next) {
1333                 if (timer_pending(&p->timer) ?
1334                     time_after(p->timer.expires, now + max_delay) :
1335                     try_to_del_timer_sync(&p->timer) >= 0)
1336                         mod_timer(&p->timer, now + max_delay);
1337         }
1338
1339 out:
1340         spin_unlock(&br->multicast_lock);
1341         return err;
1342 }
1343
1344 #if IS_ENABLED(CONFIG_IPV6)
1345 static int br_ip6_multicast_query(struct net_bridge *br,
1346                                   struct net_bridge_port *port,
1347                                   struct sk_buff *skb,
1348                                   u16 vid)
1349 {
1350         const struct ipv6hdr *ip6h = ipv6_hdr(skb);
1351         struct mld_msg *mld;
1352         struct net_bridge_mdb_entry *mp;
1353         struct mld2_query *mld2q;
1354         struct net_bridge_port_group *p;
1355         struct net_bridge_port_group __rcu **pp;
1356         struct br_ip saddr;
1357         unsigned long max_delay;
1358         unsigned long now = jiffies;
1359         const struct in6_addr *group = NULL;
1360         bool is_general_query;
1361         int err = 0;
1362
1363         spin_lock(&br->multicast_lock);
1364         if (!netif_running(br->dev) ||
1365             (port && port->state == BR_STATE_DISABLED))
1366                 goto out;
1367
1368         if (skb->len == sizeof(*mld)) {
1369                 if (!pskb_may_pull(skb, sizeof(*mld))) {
1370                         err = -EINVAL;
1371                         goto out;
1372                 }
1373                 mld = (struct mld_msg *) icmp6_hdr(skb);
1374                 max_delay = msecs_to_jiffies(ntohs(mld->mld_maxdelay));
1375                 if (max_delay)
1376                         group = &mld->mld_mca;
1377         } else {
1378                 if (!pskb_may_pull(skb, sizeof(*mld2q))) {
1379                         err = -EINVAL;
1380                         goto out;
1381                 }
1382                 mld2q = (struct mld2_query *)icmp6_hdr(skb);
1383                 if (!mld2q->mld2q_nsrcs)
1384                         group = &mld2q->mld2q_mca;
1385
1386                 max_delay = max(msecs_to_jiffies(mldv2_mrc(mld2q)), 1UL);
1387         }
1388
1389         is_general_query = group && ipv6_addr_any(group);
1390
1391         if (is_general_query) {
1392                 saddr.proto = htons(ETH_P_IPV6);
1393                 saddr.u.ip6 = ip6h->saddr;
1394
1395                 br_multicast_query_received(br, port, &br->ip6_other_query,
1396                                             &saddr, max_delay);
1397                 goto out;
1398         } else if (!group) {
1399                 goto out;
1400         }
1401
1402         mp = br_mdb_ip6_get(mlock_dereference(br->mdb, br), group, vid);
1403         if (!mp)
1404                 goto out;
1405
1406         max_delay *= br->multicast_last_member_count;
1407         if (mp->mglist &&
1408             (timer_pending(&mp->timer) ?
1409              time_after(mp->timer.expires, now + max_delay) :
1410              try_to_del_timer_sync(&mp->timer) >= 0))
1411                 mod_timer(&mp->timer, now + max_delay);
1412
1413         for (pp = &mp->ports;
1414              (p = mlock_dereference(*pp, br)) != NULL;
1415              pp = &p->next) {
1416                 if (timer_pending(&p->timer) ?
1417                     time_after(p->timer.expires, now + max_delay) :
1418                     try_to_del_timer_sync(&p->timer) >= 0)
1419                         mod_timer(&p->timer, now + max_delay);
1420         }
1421
1422 out:
1423         spin_unlock(&br->multicast_lock);
1424         return err;
1425 }
1426 #endif
1427
1428 static void
1429 br_multicast_leave_group(struct net_bridge *br,
1430                          struct net_bridge_port *port,
1431                          struct br_ip *group,
1432                          struct bridge_mcast_other_query *other_query,
1433                          struct bridge_mcast_own_query *own_query)
1434 {
1435         struct net_bridge_mdb_htable *mdb;
1436         struct net_bridge_mdb_entry *mp;
1437         struct net_bridge_port_group *p;
1438         unsigned long now;
1439         unsigned long time;
1440
1441         spin_lock(&br->multicast_lock);
1442         if (!netif_running(br->dev) ||
1443             (port && port->state == BR_STATE_DISABLED))
1444                 goto out;
1445
1446         mdb = mlock_dereference(br->mdb, br);
1447         mp = br_mdb_ip_get(mdb, group);
1448         if (!mp)
1449                 goto out;
1450
1451         if (port && (port->flags & BR_MULTICAST_FAST_LEAVE)) {
1452                 struct net_bridge_port_group __rcu **pp;
1453
1454                 for (pp = &mp->ports;
1455                      (p = mlock_dereference(*pp, br)) != NULL;
1456                      pp = &p->next) {
1457                         if (p->port != port)
1458                                 continue;
1459
1460                         rcu_assign_pointer(*pp, p->next);
1461                         hlist_del_init(&p->mglist);
1462                         del_timer(&p->timer);
1463                         call_rcu_bh(&p->rcu, br_multicast_free_pg);
1464                         br_mdb_notify(br->dev, p, RTM_DELMDB);
1465
1466                         if (!mp->ports && !mp->mglist &&
1467                             netif_running(br->dev))
1468                                 mod_timer(&mp->timer, jiffies);
1469                 }
1470                 goto out;
1471         }
1472
1473         if (timer_pending(&other_query->timer))
1474                 goto out;
1475
1476         if (br->multicast_querier) {
1477                 __br_multicast_send_query(br, port, &mp->addr);
1478
1479                 time = jiffies + br->multicast_last_member_count *
1480                                  br->multicast_last_member_interval;
1481
1482                 mod_timer(&own_query->timer, time);
1483
1484                 for (p = mlock_dereference(mp->ports, br);
1485                      p != NULL;
1486                      p = mlock_dereference(p->next, br)) {
1487                         if (p->port != port)
1488                                 continue;
1489
1490                         if (!hlist_unhashed(&p->mglist) &&
1491                             (timer_pending(&p->timer) ?
1492                              time_after(p->timer.expires, time) :
1493                              try_to_del_timer_sync(&p->timer) >= 0)) {
1494                                 mod_timer(&p->timer, time);
1495                         }
1496
1497                         break;
1498                 }
1499         }
1500
1501         now = jiffies;
1502         time = now + br->multicast_last_member_count *
1503                      br->multicast_last_member_interval;
1504
1505         if (!port) {
1506                 if (mp->mglist &&
1507                     (timer_pending(&mp->timer) ?
1508                      time_after(mp->timer.expires, time) :
1509                      try_to_del_timer_sync(&mp->timer) >= 0)) {
1510                         mod_timer(&mp->timer, time);
1511                 }
1512
1513                 goto out;
1514         }
1515
1516         for (p = mlock_dereference(mp->ports, br);
1517              p != NULL;
1518              p = mlock_dereference(p->next, br)) {
1519                 if (p->port != port)
1520                         continue;
1521
1522                 if (!hlist_unhashed(&p->mglist) &&
1523                     (timer_pending(&p->timer) ?
1524                      time_after(p->timer.expires, time) :
1525                      try_to_del_timer_sync(&p->timer) >= 0)) {
1526                         mod_timer(&p->timer, time);
1527                 }
1528
1529                 break;
1530         }
1531 out:
1532         spin_unlock(&br->multicast_lock);
1533 }
1534
1535 static void br_ip4_multicast_leave_group(struct net_bridge *br,
1536                                          struct net_bridge_port *port,
1537                                          __be32 group,
1538                                          __u16 vid)
1539 {
1540         struct br_ip br_group;
1541         struct bridge_mcast_own_query *own_query;
1542
1543         if (ipv4_is_local_multicast(group))
1544                 return;
1545
1546         own_query = port ? &port->ip4_own_query : &br->ip4_own_query;
1547
1548         br_group.u.ip4 = group;
1549         br_group.proto = htons(ETH_P_IP);
1550         br_group.vid = vid;
1551
1552         br_multicast_leave_group(br, port, &br_group, &br->ip4_other_query,
1553                                  own_query);
1554 }
1555
1556 #if IS_ENABLED(CONFIG_IPV6)
1557 static void br_ip6_multicast_leave_group(struct net_bridge *br,
1558                                          struct net_bridge_port *port,
1559                                          const struct in6_addr *group,
1560                                          __u16 vid)
1561 {
1562         struct br_ip br_group;
1563         struct bridge_mcast_own_query *own_query;
1564
1565         if (ipv6_addr_is_ll_all_nodes(group))
1566                 return;
1567
1568         own_query = port ? &port->ip6_own_query : &br->ip6_own_query;
1569
1570         br_group.u.ip6 = *group;
1571         br_group.proto = htons(ETH_P_IPV6);
1572         br_group.vid = vid;
1573
1574         br_multicast_leave_group(br, port, &br_group, &br->ip6_other_query,
1575                                  own_query);
1576 }
1577 #endif
1578
1579 static int br_multicast_ipv4_rcv(struct net_bridge *br,
1580                                  struct net_bridge_port *port,
1581                                  struct sk_buff *skb,
1582                                  u16 vid)
1583 {
1584         struct sk_buff *skb_trimmed = NULL;
1585         struct igmphdr *ih;
1586         int err;
1587
1588         err = ip_mc_check_igmp(skb, &skb_trimmed);
1589
1590         if (err == -ENOMSG) {
1591                 if (!ipv4_is_local_multicast(ip_hdr(skb)->daddr))
1592                         BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1593                 return 0;
1594         } else if (err < 0) {
1595                 return err;
1596         }
1597
1598         BR_INPUT_SKB_CB(skb)->igmp = 1;
1599         ih = igmp_hdr(skb);
1600
1601         switch (ih->type) {
1602         case IGMP_HOST_MEMBERSHIP_REPORT:
1603         case IGMPV2_HOST_MEMBERSHIP_REPORT:
1604                 BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1605                 err = br_ip4_multicast_add_group(br, port, ih->group, vid);
1606                 break;
1607         case IGMPV3_HOST_MEMBERSHIP_REPORT:
1608                 err = br_ip4_multicast_igmp3_report(br, port, skb_trimmed, vid);
1609                 break;
1610         case IGMP_HOST_MEMBERSHIP_QUERY:
1611                 err = br_ip4_multicast_query(br, port, skb_trimmed, vid);
1612                 break;
1613         case IGMP_HOST_LEAVE_MESSAGE:
1614                 br_ip4_multicast_leave_group(br, port, ih->group, vid);
1615                 break;
1616         }
1617
1618         if (skb_trimmed && skb_trimmed != skb)
1619                 kfree_skb(skb_trimmed);
1620
1621         return err;
1622 }
1623
1624 #if IS_ENABLED(CONFIG_IPV6)
1625 static int br_multicast_ipv6_rcv(struct net_bridge *br,
1626                                  struct net_bridge_port *port,
1627                                  struct sk_buff *skb,
1628                                  u16 vid)
1629 {
1630         struct sk_buff *skb_trimmed = NULL;
1631         struct mld_msg *mld;
1632         int err;
1633
1634         err = ipv6_mc_check_mld(skb, &skb_trimmed);
1635
1636         if (err == -ENOMSG) {
1637                 if (!ipv6_addr_is_ll_all_nodes(&ipv6_hdr(skb)->daddr))
1638                         BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1639                 return 0;
1640         } else if (err < 0) {
1641                 return err;
1642         }
1643
1644         BR_INPUT_SKB_CB(skb)->igmp = 1;
1645         mld = (struct mld_msg *)skb_transport_header(skb);
1646
1647         switch (mld->mld_type) {
1648         case ICMPV6_MGM_REPORT:
1649                 BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1650                 err = br_ip6_multicast_add_group(br, port, &mld->mld_mca, vid);
1651                 break;
1652         case ICMPV6_MLD2_REPORT:
1653                 err = br_ip6_multicast_mld2_report(br, port, skb_trimmed, vid);
1654                 break;
1655         case ICMPV6_MGM_QUERY:
1656                 err = br_ip6_multicast_query(br, port, skb_trimmed, vid);
1657                 break;
1658         case ICMPV6_MGM_REDUCTION:
1659                 br_ip6_multicast_leave_group(br, port, &mld->mld_mca, vid);
1660                 break;
1661         }
1662
1663         if (skb_trimmed && skb_trimmed != skb)
1664                 kfree_skb(skb_trimmed);
1665
1666         return err;
1667 }
1668 #endif
1669
1670 int br_multicast_rcv(struct net_bridge *br, struct net_bridge_port *port,
1671                      struct sk_buff *skb, u16 vid)
1672 {
1673         BR_INPUT_SKB_CB(skb)->igmp = 0;
1674         BR_INPUT_SKB_CB(skb)->mrouters_only = 0;
1675
1676         if (br->multicast_disabled)
1677                 return 0;
1678
1679         switch (skb->protocol) {
1680         case htons(ETH_P_IP):
1681                 return br_multicast_ipv4_rcv(br, port, skb, vid);
1682 #if IS_ENABLED(CONFIG_IPV6)
1683         case htons(ETH_P_IPV6):
1684                 return br_multicast_ipv6_rcv(br, port, skb, vid);
1685 #endif
1686         }
1687
1688         return 0;
1689 }
1690
1691 static void br_multicast_query_expired(struct net_bridge *br,
1692                                        struct bridge_mcast_own_query *query,
1693                                        struct bridge_mcast_querier *querier)
1694 {
1695         spin_lock(&br->multicast_lock);
1696         if (query->startup_sent < br->multicast_startup_query_count)
1697                 query->startup_sent++;
1698
1699         RCU_INIT_POINTER(querier->port, NULL);
1700         br_multicast_send_query(br, NULL, query);
1701         spin_unlock(&br->multicast_lock);
1702 }
1703
1704 static void br_ip4_multicast_query_expired(unsigned long data)
1705 {
1706         struct net_bridge *br = (void *)data;
1707
1708         br_multicast_query_expired(br, &br->ip4_own_query, &br->ip4_querier);
1709 }
1710
1711 #if IS_ENABLED(CONFIG_IPV6)
1712 static void br_ip6_multicast_query_expired(unsigned long data)
1713 {
1714         struct net_bridge *br = (void *)data;
1715
1716         br_multicast_query_expired(br, &br->ip6_own_query, &br->ip6_querier);
1717 }
1718 #endif
1719
1720 void br_multicast_init(struct net_bridge *br)
1721 {
1722         br->hash_elasticity = 4;
1723         br->hash_max = 512;
1724
1725         br->multicast_router = MDB_RTR_TYPE_TEMP_QUERY;
1726         br->multicast_querier = 0;
1727         br->multicast_query_use_ifaddr = 0;
1728         br->multicast_last_member_count = 2;
1729         br->multicast_startup_query_count = 2;
1730
1731         br->multicast_last_member_interval = HZ;
1732         br->multicast_query_response_interval = 10 * HZ;
1733         br->multicast_startup_query_interval = 125 * HZ / 4;
1734         br->multicast_query_interval = 125 * HZ;
1735         br->multicast_querier_interval = 255 * HZ;
1736         br->multicast_membership_interval = 260 * HZ;
1737
1738         br->ip4_other_query.delay_time = 0;
1739         br->ip4_querier.port = NULL;
1740 #if IS_ENABLED(CONFIG_IPV6)
1741         br->ip6_other_query.delay_time = 0;
1742         br->ip6_querier.port = NULL;
1743 #endif
1744
1745         spin_lock_init(&br->multicast_lock);
1746         setup_timer(&br->multicast_router_timer,
1747                     br_multicast_local_router_expired, 0);
1748         setup_timer(&br->ip4_other_query.timer,
1749                     br_ip4_multicast_querier_expired, (unsigned long)br);
1750         setup_timer(&br->ip4_own_query.timer, br_ip4_multicast_query_expired,
1751                     (unsigned long)br);
1752 #if IS_ENABLED(CONFIG_IPV6)
1753         setup_timer(&br->ip6_other_query.timer,
1754                     br_ip6_multicast_querier_expired, (unsigned long)br);
1755         setup_timer(&br->ip6_own_query.timer, br_ip6_multicast_query_expired,
1756                     (unsigned long)br);
1757 #endif
1758 }
1759
1760 static void __br_multicast_open(struct net_bridge *br,
1761                                 struct bridge_mcast_own_query *query)
1762 {
1763         query->startup_sent = 0;
1764
1765         if (br->multicast_disabled)
1766                 return;
1767
1768         mod_timer(&query->timer, jiffies);
1769 }
1770
1771 void br_multicast_open(struct net_bridge *br)
1772 {
1773         __br_multicast_open(br, &br->ip4_own_query);
1774 #if IS_ENABLED(CONFIG_IPV6)
1775         __br_multicast_open(br, &br->ip6_own_query);
1776 #endif
1777 }
1778
1779 void br_multicast_stop(struct net_bridge *br)
1780 {
1781         del_timer_sync(&br->multicast_router_timer);
1782         del_timer_sync(&br->ip4_other_query.timer);
1783         del_timer_sync(&br->ip4_own_query.timer);
1784 #if IS_ENABLED(CONFIG_IPV6)
1785         del_timer_sync(&br->ip6_other_query.timer);
1786         del_timer_sync(&br->ip6_own_query.timer);
1787 #endif
1788 }
1789
1790 void br_multicast_dev_del(struct net_bridge *br)
1791 {
1792         struct net_bridge_mdb_htable *mdb;
1793         struct net_bridge_mdb_entry *mp;
1794         struct hlist_node *n;
1795         u32 ver;
1796         int i;
1797
1798         spin_lock_bh(&br->multicast_lock);
1799         mdb = mlock_dereference(br->mdb, br);
1800         if (!mdb)
1801                 goto out;
1802
1803         br->mdb = NULL;
1804
1805         ver = mdb->ver;
1806         for (i = 0; i < mdb->max; i++) {
1807                 hlist_for_each_entry_safe(mp, n, &mdb->mhash[i],
1808                                           hlist[ver]) {
1809                         del_timer(&mp->timer);
1810                         call_rcu_bh(&mp->rcu, br_multicast_free_group);
1811                 }
1812         }
1813
1814         if (mdb->old) {
1815                 spin_unlock_bh(&br->multicast_lock);
1816                 rcu_barrier_bh();
1817                 spin_lock_bh(&br->multicast_lock);
1818                 WARN_ON(mdb->old);
1819         }
1820
1821         mdb->old = mdb;
1822         call_rcu_bh(&mdb->rcu, br_mdb_free);
1823
1824 out:
1825         spin_unlock_bh(&br->multicast_lock);
1826 }
1827
1828 int br_multicast_set_router(struct net_bridge *br, unsigned long val)
1829 {
1830         int err = -EINVAL;
1831
1832         spin_lock_bh(&br->multicast_lock);
1833
1834         switch (val) {
1835         case MDB_RTR_TYPE_DISABLED:
1836         case MDB_RTR_TYPE_PERM:
1837                 del_timer(&br->multicast_router_timer);
1838                 /* fall through */
1839         case MDB_RTR_TYPE_TEMP_QUERY:
1840                 br->multicast_router = val;
1841                 err = 0;
1842                 break;
1843         }
1844
1845         spin_unlock_bh(&br->multicast_lock);
1846
1847         return err;
1848 }
1849
1850 static void __del_port_router(struct net_bridge_port *p)
1851 {
1852         if (hlist_unhashed(&p->rlist))
1853                 return;
1854         hlist_del_init_rcu(&p->rlist);
1855         br_rtr_notify(p->br->dev, p, RTM_DELMDB);
1856 }
1857
1858 int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
1859 {
1860         struct net_bridge *br = p->br;
1861         unsigned long now = jiffies;
1862         int err = -EINVAL;
1863
1864         spin_lock(&br->multicast_lock);
1865         if (p->multicast_router == val) {
1866                 /* Refresh the temp router port timer */
1867                 if (p->multicast_router == MDB_RTR_TYPE_TEMP)
1868                         mod_timer(&p->multicast_router_timer,
1869                                   now + br->multicast_querier_interval);
1870                 err = 0;
1871                 goto unlock;
1872         }
1873         switch (val) {
1874         case MDB_RTR_TYPE_DISABLED:
1875                 p->multicast_router = MDB_RTR_TYPE_DISABLED;
1876                 __del_port_router(p);
1877                 del_timer(&p->multicast_router_timer);
1878                 break;
1879         case MDB_RTR_TYPE_TEMP_QUERY:
1880                 p->multicast_router = MDB_RTR_TYPE_TEMP_QUERY;
1881                 __del_port_router(p);
1882                 break;
1883         case MDB_RTR_TYPE_PERM:
1884                 p->multicast_router = MDB_RTR_TYPE_PERM;
1885                 del_timer(&p->multicast_router_timer);
1886                 br_multicast_add_router(br, p);
1887                 break;
1888         case MDB_RTR_TYPE_TEMP:
1889                 p->multicast_router = MDB_RTR_TYPE_TEMP;
1890                 br_multicast_mark_router(br, p);
1891                 break;
1892         default:
1893                 goto unlock;
1894         }
1895         err = 0;
1896 unlock:
1897         spin_unlock(&br->multicast_lock);
1898
1899         return err;
1900 }
1901
1902 static void br_multicast_start_querier(struct net_bridge *br,
1903                                        struct bridge_mcast_own_query *query)
1904 {
1905         struct net_bridge_port *port;
1906
1907         __br_multicast_open(br, query);
1908
1909         list_for_each_entry(port, &br->port_list, list) {
1910                 if (port->state == BR_STATE_DISABLED ||
1911                     port->state == BR_STATE_BLOCKING)
1912                         continue;
1913
1914                 if (query == &br->ip4_own_query)
1915                         br_multicast_enable(&port->ip4_own_query);
1916 #if IS_ENABLED(CONFIG_IPV6)
1917                 else
1918                         br_multicast_enable(&port->ip6_own_query);
1919 #endif
1920         }
1921 }
1922
1923 int br_multicast_toggle(struct net_bridge *br, unsigned long val)
1924 {
1925         int err = 0;
1926         struct net_bridge_mdb_htable *mdb;
1927
1928         spin_lock_bh(&br->multicast_lock);
1929         if (br->multicast_disabled == !val)
1930                 goto unlock;
1931
1932         br->multicast_disabled = !val;
1933         if (br->multicast_disabled)
1934                 goto unlock;
1935
1936         if (!netif_running(br->dev))
1937                 goto unlock;
1938
1939         mdb = mlock_dereference(br->mdb, br);
1940         if (mdb) {
1941                 if (mdb->old) {
1942                         err = -EEXIST;
1943 rollback:
1944                         br->multicast_disabled = !!val;
1945                         goto unlock;
1946                 }
1947
1948                 err = br_mdb_rehash(&br->mdb, mdb->max,
1949                                     br->hash_elasticity);
1950                 if (err)
1951                         goto rollback;
1952         }
1953
1954         br_multicast_start_querier(br, &br->ip4_own_query);
1955 #if IS_ENABLED(CONFIG_IPV6)
1956         br_multicast_start_querier(br, &br->ip6_own_query);
1957 #endif
1958
1959 unlock:
1960         spin_unlock_bh(&br->multicast_lock);
1961
1962         return err;
1963 }
1964
1965 int br_multicast_set_querier(struct net_bridge *br, unsigned long val)
1966 {
1967         unsigned long max_delay;
1968
1969         val = !!val;
1970
1971         spin_lock_bh(&br->multicast_lock);
1972         if (br->multicast_querier == val)
1973                 goto unlock;
1974
1975         br->multicast_querier = val;
1976         if (!val)
1977                 goto unlock;
1978
1979         max_delay = br->multicast_query_response_interval;
1980
1981         if (!timer_pending(&br->ip4_other_query.timer))
1982                 br->ip4_other_query.delay_time = jiffies + max_delay;
1983
1984         br_multicast_start_querier(br, &br->ip4_own_query);
1985
1986 #if IS_ENABLED(CONFIG_IPV6)
1987         if (!timer_pending(&br->ip6_other_query.timer))
1988                 br->ip6_other_query.delay_time = jiffies + max_delay;
1989
1990         br_multicast_start_querier(br, &br->ip6_own_query);
1991 #endif
1992
1993 unlock:
1994         spin_unlock_bh(&br->multicast_lock);
1995
1996         return 0;
1997 }
1998
1999 int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val)
2000 {
2001         int err = -EINVAL;
2002         u32 old;
2003         struct net_bridge_mdb_htable *mdb;
2004
2005         spin_lock_bh(&br->multicast_lock);
2006         if (!is_power_of_2(val))
2007                 goto unlock;
2008
2009         mdb = mlock_dereference(br->mdb, br);
2010         if (mdb && val < mdb->size)
2011                 goto unlock;
2012
2013         err = 0;
2014
2015         old = br->hash_max;
2016         br->hash_max = val;
2017
2018         if (mdb) {
2019                 if (mdb->old) {
2020                         err = -EEXIST;
2021 rollback:
2022                         br->hash_max = old;
2023                         goto unlock;
2024                 }
2025
2026                 err = br_mdb_rehash(&br->mdb, br->hash_max,
2027                                     br->hash_elasticity);
2028                 if (err)
2029                         goto rollback;
2030         }
2031
2032 unlock:
2033         spin_unlock_bh(&br->multicast_lock);
2034
2035         return err;
2036 }
2037
2038 /**
2039  * br_multicast_list_adjacent - Returns snooped multicast addresses
2040  * @dev:        The bridge port adjacent to which to retrieve addresses
2041  * @br_ip_list: The list to store found, snooped multicast IP addresses in
2042  *
2043  * Creates a list of IP addresses (struct br_ip_list) sensed by the multicast
2044  * snooping feature on all bridge ports of dev's bridge device, excluding
2045  * the addresses from dev itself.
2046  *
2047  * Returns the number of items added to br_ip_list.
2048  *
2049  * Notes:
2050  * - br_ip_list needs to be initialized by caller
2051  * - br_ip_list might contain duplicates in the end
2052  *   (needs to be taken care of by caller)
2053  * - br_ip_list needs to be freed by caller
2054  */
2055 int br_multicast_list_adjacent(struct net_device *dev,
2056                                struct list_head *br_ip_list)
2057 {
2058         struct net_bridge *br;
2059         struct net_bridge_port *port;
2060         struct net_bridge_port_group *group;
2061         struct br_ip_list *entry;
2062         int count = 0;
2063
2064         rcu_read_lock();
2065         if (!br_ip_list || !br_port_exists(dev))
2066                 goto unlock;
2067
2068         port = br_port_get_rcu(dev);
2069         if (!port || !port->br)
2070                 goto unlock;
2071
2072         br = port->br;
2073
2074         list_for_each_entry_rcu(port, &br->port_list, list) {
2075                 if (!port->dev || port->dev == dev)
2076                         continue;
2077
2078                 hlist_for_each_entry_rcu(group, &port->mglist, mglist) {
2079                         entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
2080                         if (!entry)
2081                                 goto unlock;
2082
2083                         entry->addr = group->addr;
2084                         list_add(&entry->list, br_ip_list);
2085                         count++;
2086                 }
2087         }
2088
2089 unlock:
2090         rcu_read_unlock();
2091         return count;
2092 }
2093 EXPORT_SYMBOL_GPL(br_multicast_list_adjacent);
2094
2095 /**
2096  * br_multicast_has_querier_anywhere - Checks for a querier on a bridge
2097  * @dev: The bridge port providing the bridge on which to check for a querier
2098  * @proto: The protocol family to check for: IGMP -> ETH_P_IP, MLD -> ETH_P_IPV6
2099  *
2100  * Checks whether the given interface has a bridge on top and if so returns
2101  * true if a valid querier exists anywhere on the bridged link layer.
2102  * Otherwise returns false.
2103  */
2104 bool br_multicast_has_querier_anywhere(struct net_device *dev, int proto)
2105 {
2106         struct net_bridge *br;
2107         struct net_bridge_port *port;
2108         struct ethhdr eth;
2109         bool ret = false;
2110
2111         rcu_read_lock();
2112         if (!br_port_exists(dev))
2113                 goto unlock;
2114
2115         port = br_port_get_rcu(dev);
2116         if (!port || !port->br)
2117                 goto unlock;
2118
2119         br = port->br;
2120
2121         memset(&eth, 0, sizeof(eth));
2122         eth.h_proto = htons(proto);
2123
2124         ret = br_multicast_querier_exists(br, &eth);
2125
2126 unlock:
2127         rcu_read_unlock();
2128         return ret;
2129 }
2130 EXPORT_SYMBOL_GPL(br_multicast_has_querier_anywhere);
2131
2132 /**
2133  * br_multicast_has_querier_adjacent - Checks for a querier behind a bridge port
2134  * @dev: The bridge port adjacent to which to check for a querier
2135  * @proto: The protocol family to check for: IGMP -> ETH_P_IP, MLD -> ETH_P_IPV6
2136  *
2137  * Checks whether the given interface has a bridge on top and if so returns
2138  * true if a selected querier is behind one of the other ports of this
2139  * bridge. Otherwise returns false.
2140  */
2141 bool br_multicast_has_querier_adjacent(struct net_device *dev, int proto)
2142 {
2143         struct net_bridge *br;
2144         struct net_bridge_port *port;
2145         bool ret = false;
2146
2147         rcu_read_lock();
2148         if (!br_port_exists(dev))
2149                 goto unlock;
2150
2151         port = br_port_get_rcu(dev);
2152         if (!port || !port->br)
2153                 goto unlock;
2154
2155         br = port->br;
2156
2157         switch (proto) {
2158         case ETH_P_IP:
2159                 if (!timer_pending(&br->ip4_other_query.timer) ||
2160                     rcu_dereference(br->ip4_querier.port) == port)
2161                         goto unlock;
2162                 break;
2163 #if IS_ENABLED(CONFIG_IPV6)
2164         case ETH_P_IPV6:
2165                 if (!timer_pending(&br->ip6_other_query.timer) ||
2166                     rcu_dereference(br->ip6_querier.port) == port)
2167                         goto unlock;
2168                 break;
2169 #endif
2170         default:
2171                 goto unlock;
2172         }
2173
2174         ret = true;
2175 unlock:
2176         rcu_read_unlock();
2177         return ret;
2178 }
2179 EXPORT_SYMBOL_GPL(br_multicast_has_querier_adjacent);