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 unsigned int br_mdb_rehash_seq;
  43
  44 static inline int br_ip_equal(const struct br_ip *a, const struct br_ip *b)
  45 {
  46         if (a->proto != b->proto)
  47                 return 0;
  48         if (a->vid != b->vid)
  49                 return 0;
  50         switch (a->proto) {
  51         case htons(ETH_P_IP):
  52                 return a->u.ip4 == b->u.ip4;
  53 #if IS_ENABLED(CONFIG_IPV6)
  54         case htons(ETH_P_IPV6):
  55                 return ipv6_addr_equal(&a->u.ip6, &b->u.ip6);
  56 #endif
  57         }
  58         return 0;
  59 }
  60
  61 static inline int __br_ip4_hash(struct net_bridge_mdb_htable *mdb, __be32 ip,
  62                                 __u16 vid)
  63 {
  64         return jhash_2words((__force u32)ip, vid, mdb->secret) & (mdb->max - 1);
  65 }
  66
  67 #if IS_ENABLED(CONFIG_IPV6)
  68 static inline int __br_ip6_hash(struct net_bridge_mdb_htable *mdb,
  69                                 const struct in6_addr *ip,
  70                                 __u16 vid)
  71 {
  72         return jhash_2words(ipv6_addr_hash(ip), vid,
  73                             mdb->secret) & (mdb->max - 1);
  74 }
  75 #endif
  76
  77 static inline int br_ip_hash(struct net_bridge_mdb_htable *mdb,
  78                              struct br_ip *ip)
  79 {
  80         switch (ip->proto) {
  81         case htons(ETH_P_IP):
  82                 return __br_ip4_hash(mdb, ip->u.ip4, ip->vid);
  83 #if IS_ENABLED(CONFIG_IPV6)
  84         case htons(ETH_P_IPV6):
  85                 return __br_ip6_hash(mdb, &ip->u.ip6, ip->vid);
  86 #endif
  87         }
  88         return 0;
  89 }
  90
  91 static struct net_bridge_mdb_entry *__br_mdb_ip_get(
  92         struct net_bridge_mdb_htable *mdb, struct br_ip *dst, int hash)
  93 {
  94         struct net_bridge_mdb_entry *mp;
  95
  96         hlist_for_each_entry_rcu(mp, &mdb->mhash[hash], hlist[mdb->ver]) {
  97                 if (br_ip_equal(&mp->addr, dst))
  98                         return mp;
  99         }
 100
 101         return NULL;
 102 }
 103
 104 struct net_bridge_mdb_entry *br_mdb_ip_get(struct net_bridge_mdb_htable *mdb,
 105                                            struct br_ip *dst)
 106 {
 107         if (!mdb)
 108                 return NULL;
 109
 110         return __br_mdb_ip_get(mdb, dst, br_ip_hash(mdb, dst));
 111 }
 112
 113 static struct net_bridge_mdb_entry *br_mdb_ip4_get(
 114         struct net_bridge_mdb_htable *mdb, __be32 dst, __u16 vid)
 115 {
 116         struct br_ip br_dst;
 117
 118         br_dst.u.ip4 = dst;
 119         br_dst.proto = htons(ETH_P_IP);
 120         br_dst.vid = vid;
 121
 122         return br_mdb_ip_get(mdb, &br_dst);
 123 }
 124
 125 #if IS_ENABLED(CONFIG_IPV6)
 126 static struct net_bridge_mdb_entry *br_mdb_ip6_get(
 127         struct net_bridge_mdb_htable *mdb, const struct in6_addr *dst,
 128         __u16 vid)
 129 {
 130         struct br_ip br_dst;
 131
 132         br_dst.u.ip6 = *dst;
 133         br_dst.proto = htons(ETH_P_IPV6);
 134         br_dst.vid = vid;
 135
 136         return br_mdb_ip_get(mdb, &br_dst);
 137 }
 138 #endif
 139
 140 struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br,
 141                                         struct sk_buff *skb, u16 vid)
 142 {
 143         struct net_bridge_mdb_htable *mdb = rcu_dereference(br->mdb);
 144         struct br_ip ip;
 145
 146         if (br->multicast_disabled)
 147                 return NULL;
 148
 149         if (BR_INPUT_SKB_CB(skb)->igmp)
 150                 return NULL;
 151
 152         ip.proto = skb->protocol;
 153         ip.vid = vid;
 154
 155         switch (skb->protocol) {
 156         case htons(ETH_P_IP):
 157                 ip.u.ip4 = ip_hdr(skb)->daddr;
 158                 break;
 159 #if IS_ENABLED(CONFIG_IPV6)
 160         case htons(ETH_P_IPV6):
 161                 ip.u.ip6 = ipv6_hdr(skb)->daddr;
 162                 break;
 163 #endif
 164         default:
 165                 return NULL;
 166         }
 167
 168         return br_mdb_ip_get(mdb, &ip);
 169 }
 170
 171 static void br_mdb_free(struct rcu_head *head)
 172 {
 173         struct net_bridge_mdb_htable *mdb =
 174                 container_of(head, struct net_bridge_mdb_htable, rcu);
 175         struct net_bridge_mdb_htable *old = mdb->old;
 176
 177         mdb->old = NULL;
 178         kfree(old->mhash);
 179         kfree(old);
 180 }
 181
 182 static int br_mdb_copy(struct net_bridge_mdb_htable *new,
 183                        struct net_bridge_mdb_htable *old,
 184                        int elasticity)
 185 {
 186         struct net_bridge_mdb_entry *mp;
 187         int maxlen;
 188         int len;
 189         int i;
 190
 191         for (i = 0; i < old->max; i++)
 192                 hlist_for_each_entry(mp, &old->mhash[i], hlist[old->ver])
 193                         hlist_add_head(&mp->hlist[new->ver],
 194                                        &new->mhash[br_ip_hash(new, &mp->addr)]);
 195
 196         if (!elasticity)
 197                 return 0;
 198
 199         maxlen = 0;
 200         for (i = 0; i < new->max; i++) {
 201                 len = 0;
 202                 hlist_for_each_entry(mp, &new->mhash[i], hlist[new->ver])
 203                         len++;
 204                 if (len > maxlen)
 205                         maxlen = len;
 206         }
 207
 208         return maxlen > elasticity ? -EINVAL : 0;
 209 }
 210
 211 void br_multicast_free_pg(struct rcu_head *head)
 212 {
 213         struct net_bridge_port_group *p =
 214                 container_of(head, struct net_bridge_port_group, rcu);
 215
 216         kfree(p);
 217 }
 218
 219 static void br_multicast_free_group(struct rcu_head *head)
 220 {
 221         struct net_bridge_mdb_entry *mp =
 222                 container_of(head, struct net_bridge_mdb_entry, rcu);
 223
 224         kfree(mp);
 225 }
 226
 227 static void br_multicast_group_expired(unsigned long data)
 228 {
 229         struct net_bridge_mdb_entry *mp = (void *)data;
 230         struct net_bridge *br = mp->br;
 231         struct net_bridge_mdb_htable *mdb;
 232
 233         spin_lock(&br->multicast_lock);
 234         if (!netif_running(br->dev) || timer_pending(&mp->timer))
 235                 goto out;
 236
 237         mp->mglist = false;
 238
 239         if (mp->ports)
 240                 goto out;
 241
 242         mdb = mlock_dereference(br->mdb, br);
 243
 244         hlist_del_rcu(&mp->hlist[mdb->ver]);
 245         mdb->size--;
 246
 247         call_rcu_bh(&mp->rcu, br_multicast_free_group);
 248
 249 out:
 250         spin_unlock(&br->multicast_lock);
 251 }
 252
 253 static void br_multicast_del_pg(struct net_bridge *br,
 254                                 struct net_bridge_port_group *pg)
 255 {
 256         struct net_bridge_mdb_htable *mdb;
 257         struct net_bridge_mdb_entry *mp;
 258         struct net_bridge_port_group *p;
 259         struct net_bridge_port_group __rcu **pp;
 260
 261         mdb = mlock_dereference(br->mdb, br);
 262
 263         mp = br_mdb_ip_get(mdb, &pg->addr);
 264         if (WARN_ON(!mp))
 265                 return;
 266
 267         for (pp = &mp->ports;
 268              (p = mlock_dereference(*pp, br)) != NULL;
 269              pp = &p->next) {
 270                 if (p != pg)
 271                         continue;
 272
 273                 rcu_assign_pointer(*pp, p->next);
 274                 hlist_del_init(&p->mglist);
 275                 del_timer(&p->timer);
 276                 call_rcu_bh(&p->rcu, br_multicast_free_pg);
 277
 278                 if (!mp->ports && !mp->mglist &&
 279                     netif_running(br->dev))
 280                         mod_timer(&mp->timer, jiffies);
 281
 282                 return;
 283         }
 284
 285         WARN_ON(1);
 286 }
 287
 288 static void br_multicast_port_group_expired(unsigned long data)
 289 {
 290         struct net_bridge_port_group *pg = (void *)data;
 291         struct net_bridge *br = pg->port->br;
 292
 293         spin_lock(&br->multicast_lock);
 294         if (!netif_running(br->dev) || timer_pending(&pg->timer) ||
 295             hlist_unhashed(&pg->mglist) || pg->state & MDB_PERMANENT)
 296                 goto out;
 297
 298         br_multicast_del_pg(br, pg);
 299
 300 out:
 301         spin_unlock(&br->multicast_lock);
 302 }
 303
 304 static int br_mdb_rehash(struct net_bridge_mdb_htable __rcu **mdbp, int max,
 305                          int elasticity)
 306 {
 307         struct net_bridge_mdb_htable *old = rcu_dereference_protected(*mdbp, 1);
 308         struct net_bridge_mdb_htable *mdb;
 309         int err;
 310
 311         mdb = kmalloc(sizeof(*mdb), GFP_ATOMIC);
 312         if (!mdb)
 313                 return -ENOMEM;
 314
 315         mdb->max = max;
 316         mdb->old = old;
 317
 318         mdb->mhash = kzalloc(max * sizeof(*mdb->mhash), GFP_ATOMIC);
 319         if (!mdb->mhash) {
 320                 kfree(mdb);
 321                 return -ENOMEM;
 322         }
 323
 324         mdb->size = old ? old->size : 0;
 325         mdb->ver = old ? old->ver ^ 1 : 0;
 326
 327         if (!old || elasticity)
 328                 get_random_bytes(&mdb->secret, sizeof(mdb->secret));
 329         else
 330                 mdb->secret = old->secret;
 331
 332         if (!old)
 333                 goto out;
 334
 335         err = br_mdb_copy(mdb, old, elasticity);
 336         if (err) {
 337                 kfree(mdb->mhash);
 338                 kfree(mdb);
 339                 return err;
 340         }
 341
 342         br_mdb_rehash_seq++;
 343         call_rcu_bh(&mdb->rcu, br_mdb_free);
 344
 345 out:
 346         rcu_assign_pointer(*mdbp, mdb);
 347
 348         return 0;
 349 }
 350
 351 static struct sk_buff *br_ip4_multicast_alloc_query(struct net_bridge *br,
 352                                                     __be32 group)
 353 {
 354         struct sk_buff *skb;
 355         struct igmphdr *ih;
 356         struct ethhdr *eth;
 357         struct iphdr *iph;
 358
 359         skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*iph) +
 360                                                  sizeof(*ih) + 4);
 361         if (!skb)
 362                 goto out;
 363
 364         skb->protocol = htons(ETH_P_IP);
 365
 366         skb_reset_mac_header(skb);
 367         eth = eth_hdr(skb);
 368
 369         ether_addr_copy(eth->h_source, br->dev->dev_addr);
 370         eth->h_dest[0] = 1;
 371         eth->h_dest[1] = 0;
 372         eth->h_dest[2] = 0x5e;
 373         eth->h_dest[3] = 0;
 374         eth->h_dest[4] = 0;
 375         eth->h_dest[5] = 1;
 376         eth->h_proto = htons(ETH_P_IP);
 377         skb_put(skb, sizeof(*eth));
 378
 379         skb_set_network_header(skb, skb->len);
 380         iph = ip_hdr(skb);
 381
 382         iph->version = 4;
 383         iph->ihl = 6;
 384         iph->tos = 0xc0;
 385         iph->tot_len = htons(sizeof(*iph) + sizeof(*ih) + 4);
 386         iph->id = 0;
 387         iph->frag_off = htons(IP_DF);
 388         iph->ttl = 1;
 389         iph->protocol = IPPROTO_IGMP;
 390         iph->saddr = br->multicast_query_use_ifaddr ?
 391                      inet_select_addr(br->dev, 0, RT_SCOPE_LINK) : 0;
 392         iph->daddr = htonl(INADDR_ALLHOSTS_GROUP);
 393         ((u8 *)&iph[1])[0] = IPOPT_RA;
 394         ((u8 *)&iph[1])[1] = 4;
 395         ((u8 *)&iph[1])[2] = 0;
 396         ((u8 *)&iph[1])[3] = 0;
 397         ip_send_check(iph);
 398         skb_put(skb, 24);
 399
 400         skb_set_transport_header(skb, skb->len);
 401         ih = igmp_hdr(skb);
 402         ih->type = IGMP_HOST_MEMBERSHIP_QUERY;
 403         ih->code = (group ? br->multicast_last_member_interval :
 404                             br->multicast_query_response_interval) /
 405                    (HZ / IGMP_TIMER_SCALE);
 406         ih->group = group;
 407         ih->csum = 0;
 408         ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
 409         skb_put(skb, sizeof(*ih));
 410
 411         __skb_pull(skb, sizeof(*eth));
 412
 413 out:
 414         return skb;
 415 }
 416
 417 #if IS_ENABLED(CONFIG_IPV6)
 418 static struct sk_buff *br_ip6_multicast_alloc_query(struct net_bridge *br,
 419                                                     const struct in6_addr *group)
 420 {
 421         struct sk_buff *skb;
 422         struct ipv6hdr *ip6h;
 423         struct mld_msg *mldq;
 424         struct ethhdr *eth;
 425         u8 *hopopt;
 426         unsigned long interval;
 427
 428         skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*ip6h) +
 429                                                  8 + sizeof(*mldq));
 430         if (!skb)
 431                 goto out;
 432
 433         skb->protocol = htons(ETH_P_IPV6);
 434
 435         /* Ethernet header */
 436         skb_reset_mac_header(skb);
 437         eth = eth_hdr(skb);
 438
 439         ether_addr_copy(eth->h_source, br->dev->dev_addr);
 440         eth->h_proto = htons(ETH_P_IPV6);
 441         skb_put(skb, sizeof(*eth));
 442
 443         /* IPv6 header + HbH option */
 444         skb_set_network_header(skb, skb->len);
 445         ip6h = ipv6_hdr(skb);
 446
 447         *(__force __be32 *)ip6h = htonl(0x60000000);
 448         ip6h->payload_len = htons(8 + sizeof(*mldq));
 449         ip6h->nexthdr = IPPROTO_HOPOPTS;
 450         ip6h->hop_limit = 1;
 451         ipv6_addr_set(&ip6h->daddr, htonl(0xff020000), 0, 0, htonl(1));
 452         if (ipv6_dev_get_saddr(dev_net(br->dev), br->dev, &ip6h->daddr, 0,
 453                                &ip6h->saddr)) {
 454                 kfree_skb(skb);
 455                 return NULL;
 456         }
 457         ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest);
 458
 459         hopopt = (u8 *)(ip6h + 1);
 460         hopopt[0] = IPPROTO_ICMPV6;             /* next hdr */
 461         hopopt[1] = 0;                          /* length of HbH */
 462         hopopt[2] = IPV6_TLV_ROUTERALERT;       /* Router Alert */
 463         hopopt[3] = 2;                          /* Length of RA Option */
 464         hopopt[4] = 0;                          /* Type = 0x0000 (MLD) */
 465         hopopt[5] = 0;
 466         hopopt[6] = IPV6_TLV_PAD1;              /* Pad1 */
 467         hopopt[7] = IPV6_TLV_PAD1;              /* Pad1 */
 468
 469         skb_put(skb, sizeof(*ip6h) + 8);
 470
 471         /* ICMPv6 */
 472         skb_set_transport_header(skb, skb->len);
 473         mldq = (struct mld_msg *) icmp6_hdr(skb);
 474
 475         interval = ipv6_addr_any(group) ?
 476                         br->multicast_query_response_interval :
 477                         br->multicast_last_member_interval;
 478
 479         mldq->mld_type = ICMPV6_MGM_QUERY;
 480         mldq->mld_code = 0;
 481         mldq->mld_cksum = 0;
 482         mldq->mld_maxdelay = htons((u16)jiffies_to_msecs(interval));
 483         mldq->mld_reserved = 0;
 484         mldq->mld_mca = *group;
 485
 486         /* checksum */
 487         mldq->mld_cksum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
 488                                           sizeof(*mldq), IPPROTO_ICMPV6,
 489                                           csum_partial(mldq,
 490                                                        sizeof(*mldq), 0));
 491         skb_put(skb, sizeof(*mldq));
 492
 493         __skb_pull(skb, sizeof(*eth));
 494
 495 out:
 496         return skb;
 497 }
 498 #endif
 499
 500 static struct sk_buff *br_multicast_alloc_query(struct net_bridge *br,
 501                                                 struct br_ip *addr)
 502 {
 503         switch (addr->proto) {
 504         case htons(ETH_P_IP):
 505                 return br_ip4_multicast_alloc_query(br, addr->u.ip4);
 506 #if IS_ENABLED(CONFIG_IPV6)
 507         case htons(ETH_P_IPV6):
 508                 return br_ip6_multicast_alloc_query(br, &addr->u.ip6);
 509 #endif
 510         }
 511         return NULL;
 512 }
 513
 514 static struct net_bridge_mdb_entry *br_multicast_get_group(
 515         struct net_bridge *br, struct net_bridge_port *port,
 516         struct br_ip *group, int hash)
 517 {
 518         struct net_bridge_mdb_htable *mdb;
 519         struct net_bridge_mdb_entry *mp;
 520         unsigned int count = 0;
 521         unsigned int max;
 522         int elasticity;
 523         int err;
 524
 525         mdb = rcu_dereference_protected(br->mdb, 1);
 526         hlist_for_each_entry(mp, &mdb->mhash[hash], hlist[mdb->ver]) {
 527                 count++;
 528                 if (unlikely(br_ip_equal(group, &mp->addr)))
 529                         return mp;
 530         }
 531
 532         elasticity = 0;
 533         max = mdb->max;
 534
 535         if (unlikely(count > br->hash_elasticity && count)) {
 536                 if (net_ratelimit())
 537                         br_info(br, "Multicast hash table "
 538                                 "chain limit reached: %s\n",
 539                                 port ? port->dev->name : br->dev->name);
 540
 541                 elasticity = br->hash_elasticity;
 542         }
 543
 544         if (mdb->size >= max) {
 545                 max *= 2;
 546                 if (unlikely(max > br->hash_max)) {
 547                         br_warn(br, "Multicast hash table maximum of %d "
 548                                 "reached, disabling snooping: %s\n",
 549                                 br->hash_max,
 550                                 port ? port->dev->name : br->dev->name);
 551                         err = -E2BIG;
 552 disable:
 553                         br->multicast_disabled = 1;
 554                         goto err;
 555                 }
 556         }
 557
 558         if (max > mdb->max || elasticity) {
 559                 if (mdb->old) {
 560                         if (net_ratelimit())
 561                                 br_info(br, "Multicast hash table "
 562                                         "on fire: %s\n",
 563                                         port ? port->dev->name : br->dev->name);
 564                         err = -EEXIST;
 565                         goto err;
 566                 }
 567
 568                 err = br_mdb_rehash(&br->mdb, max, elasticity);
 569                 if (err) {
 570                         br_warn(br, "Cannot rehash multicast "
 571                                 "hash table, disabling snooping: %s, %d, %d\n",
 572                                 port ? port->dev->name : br->dev->name,
 573                                 mdb->size, err);
 574                         goto disable;
 575                 }
 576
 577                 err = -EAGAIN;
 578                 goto err;
 579         }
 580
 581         return NULL;
 582
 583 err:
 584         mp = ERR_PTR(err);
 585         return mp;
 586 }
 587
 588 struct net_bridge_mdb_entry *br_multicast_new_group(struct net_bridge *br,
 589         struct net_bridge_port *port, struct br_ip *group)
 590 {
 591         struct net_bridge_mdb_htable *mdb;
 592         struct net_bridge_mdb_entry *mp;
 593         int hash;
 594         int err;
 595
 596         mdb = rcu_dereference_protected(br->mdb, 1);
 597         if (!mdb) {
 598                 err = br_mdb_rehash(&br->mdb, BR_HASH_SIZE, 0);
 599                 if (err)
 600                         return ERR_PTR(err);
 601                 goto rehash;
 602         }
 603
 604         hash = br_ip_hash(mdb, group);
 605         mp = br_multicast_get_group(br, port, group, hash);
 606         switch (PTR_ERR(mp)) {
 607         case 0:
 608                 break;
 609
 610         case -EAGAIN:
 611 rehash:
 612                 mdb = rcu_dereference_protected(br->mdb, 1);
 613                 hash = br_ip_hash(mdb, group);
 614                 break;
 615
 616         default:
 617                 goto out;
 618         }
 619
 620         mp = kzalloc(sizeof(*mp), GFP_ATOMIC);
 621         if (unlikely(!mp))
 622                 return ERR_PTR(-ENOMEM);
 623
 624         mp->br = br;
 625         mp->addr = *group;
 626         setup_timer(&mp->timer, br_multicast_group_expired,
 627                     (unsigned long)mp);
 628
 629         hlist_add_head_rcu(&mp->hlist[mdb->ver], &mdb->mhash[hash]);
 630         mdb->size++;
 631
 632 out:
 633         return mp;
 634 }
 635
 636 struct net_bridge_port_group *br_multicast_new_port_group(
 637                         struct net_bridge_port *port,
 638                         struct br_ip *group,
 639                         struct net_bridge_port_group __rcu *next,
 640                         unsigned char state)
 641 {
 642         struct net_bridge_port_group *p;
 643
 644         p = kzalloc(sizeof(*p), GFP_ATOMIC);
 645         if (unlikely(!p))
 646                 return NULL;
 647
 648         p->addr = *group;
 649         p->port = port;
 650         p->state = state;
 651         rcu_assign_pointer(p->next, next);
 652         hlist_add_head(&p->mglist, &port->mglist);
 653         setup_timer(&p->timer, br_multicast_port_group_expired,
 654                     (unsigned long)p);
 655         return p;
 656 }
 657
 658 static int br_multicast_add_group(struct net_bridge *br,
 659                                   struct net_bridge_port *port,
 660                                   struct br_ip *group)
 661 {
 662         struct net_bridge_mdb_entry *mp;
 663         struct net_bridge_port_group *p;
 664         struct net_bridge_port_group __rcu **pp;
 665         unsigned long now = jiffies;
 666         int err;
 667
 668         spin_lock(&br->multicast_lock);
 669         if (!netif_running(br->dev) ||
 670             (port && port->state == BR_STATE_DISABLED))
 671                 goto out;
 672
 673         mp = br_multicast_new_group(br, port, group);
 674         err = PTR_ERR(mp);
 675         if (IS_ERR(mp))
 676                 goto err;
 677
 678         if (!port) {
 679                 mp->mglist = true;
 680                 mod_timer(&mp->timer, now + br->multicast_membership_interval);
 681                 goto out;
 682         }
 683
 684         for (pp = &mp->ports;
 685              (p = mlock_dereference(*pp, br)) != NULL;
 686              pp = &p->next) {
 687                 if (p->port == port)
 688                         goto found;
 689                 if ((unsigned long)p->port < (unsigned long)port)
 690                         break;
 691         }
 692
 693         p = br_multicast_new_port_group(port, group, *pp, MDB_TEMPORARY);
 694         if (unlikely(!p))
 695                 goto err;
 696         rcu_assign_pointer(*pp, p);
 697         br_mdb_notify(br->dev, port, group, RTM_NEWMDB);
 698
 699 found:
 700         mod_timer(&p->timer, now + br->multicast_membership_interval);
 701 out:
 702         err = 0;
 703
 704 err:
 705         spin_unlock(&br->multicast_lock);
 706         return err;
 707 }
 708
 709 static int br_ip4_multicast_add_group(struct net_bridge *br,
 710                                       struct net_bridge_port *port,
 711                                       __be32 group,
 712                                       __u16 vid)
 713 {
 714         struct br_ip br_group;
 715
 716         if (ipv4_is_local_multicast(group))
 717                 return 0;
 718
 719         br_group.u.ip4 = group;
 720         br_group.proto = htons(ETH_P_IP);
 721         br_group.vid = vid;
 722
 723         return br_multicast_add_group(br, port, &br_group);
 724 }
 725
 726 #if IS_ENABLED(CONFIG_IPV6)
 727 static int br_ip6_multicast_add_group(struct net_bridge *br,
 728                                       struct net_bridge_port *port,
 729                                       const struct in6_addr *group,
 730                                       __u16 vid)
 731 {
 732         struct br_ip br_group;
 733
 734         if (ipv6_addr_is_ll_all_nodes(group))
 735                 return 0;
 736
 737         br_group.u.ip6 = *group;
 738         br_group.proto = htons(ETH_P_IPV6);
 739         br_group.vid = vid;
 740
 741         return br_multicast_add_group(br, port, &br_group);
 742 }
 743 #endif
 744
 745 static void br_multicast_router_expired(unsigned long data)
 746 {
 747         struct net_bridge_port *port = (void *)data;
 748         struct net_bridge *br = port->br;
 749
 750         spin_lock(&br->multicast_lock);
 751         if (port->multicast_router != 1 ||
 752             timer_pending(&port->multicast_router_timer) ||
 753             hlist_unhashed(&port->rlist))
 754                 goto out;
 755
 756         hlist_del_init_rcu(&port->rlist);
 757
 758 out:
 759         spin_unlock(&br->multicast_lock);
 760 }
 761
 762 static void br_multicast_local_router_expired(unsigned long data)
 763 {
 764 }
 765
 766 static void br_multicast_querier_expired(struct net_bridge *br,
 767                                          struct bridge_mcast_own_query *query)
 768 {
 769         spin_lock(&br->multicast_lock);
 770         if (!netif_running(br->dev) || br->multicast_disabled)
 771                 goto out;
 772
 773         br_multicast_start_querier(br, query);
 774
 775 out:
 776         spin_unlock(&br->multicast_lock);
 777 }
 778
 779 static void br_ip4_multicast_querier_expired(unsigned long data)
 780 {
 781         struct net_bridge *br = (void *)data;
 782
 783         br_multicast_querier_expired(br, &br->ip4_own_query);
 784 }
 785
 786 #if IS_ENABLED(CONFIG_IPV6)
 787 static void br_ip6_multicast_querier_expired(unsigned long data)
 788 {
 789         struct net_bridge *br = (void *)data;
 790
 791         br_multicast_querier_expired(br, &br->ip6_own_query);
 792 }
 793 #endif
 794
 795 static void br_multicast_select_own_querier(struct net_bridge *br,
 796                                             struct br_ip *ip,
 797                                             struct sk_buff *skb)
 798 {
 799         if (ip->proto == htons(ETH_P_IP))
 800                 br->ip4_querier.addr.u.ip4 = ip_hdr(skb)->saddr;
 801 #if IS_ENABLED(CONFIG_IPV6)
 802         else
 803                 br->ip6_querier.addr.u.ip6 = ipv6_hdr(skb)->saddr;
 804 #endif
 805 }
 806
 807 static void __br_multicast_send_query(struct net_bridge *br,
 808                                       struct net_bridge_port *port,
 809                                       struct br_ip *ip)
 810 {
 811         struct sk_buff *skb;
 812
 813         skb = br_multicast_alloc_query(br, ip);
 814         if (!skb)
 815                 return;
 816
 817         if (port) {
 818                 skb->dev = port->dev;
 819                 NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT, NULL, skb,
 820                         NULL, skb->dev,
 821                         br_dev_queue_push_xmit);
 822         } else {
 823                 br_multicast_select_own_querier(br, ip, skb);
 824                 netif_rx(skb);
 825         }
 826 }
 827
 828 static void br_multicast_send_query(struct net_bridge *br,
 829                                     struct net_bridge_port *port,
 830                                     struct bridge_mcast_own_query *own_query)
 831 {
 832         unsigned long time;
 833         struct br_ip br_group;
 834         struct bridge_mcast_other_query *other_query = NULL;
 835
 836         if (!netif_running(br->dev) || br->multicast_disabled ||
 837             !br->multicast_querier)
 838                 return;
 839
 840         memset(&br_group.u, 0, sizeof(br_group.u));
 841
 842         if (port ? (own_query == &port->ip4_own_query) :
 843                    (own_query == &br->ip4_own_query)) {
 844                 other_query = &br->ip4_other_query;
 845                 br_group.proto = htons(ETH_P_IP);
 846 #if IS_ENABLED(CONFIG_IPV6)
 847         } else {
 848                 other_query = &br->ip6_other_query;
 849                 br_group.proto = htons(ETH_P_IPV6);
 850 #endif
 851         }
 852
 853         if (!other_query || timer_pending(&other_query->timer))
 854                 return;
 855
 856         __br_multicast_send_query(br, port, &br_group);
 857
 858         time = jiffies;
 859         time += own_query->startup_sent < br->multicast_startup_query_count ?
 860                 br->multicast_startup_query_interval :
 861                 br->multicast_query_interval;
 862         mod_timer(&own_query->timer, time);
 863 }
 864
 865 static void
 866 br_multicast_port_query_expired(struct net_bridge_port *port,
 867                                 struct bridge_mcast_own_query *query)
 868 {
 869         struct net_bridge *br = port->br;
 870
 871         spin_lock(&br->multicast_lock);
 872         if (port->state == BR_STATE_DISABLED ||
 873             port->state == BR_STATE_BLOCKING)
 874                 goto out;
 875
 876         if (query->startup_sent < br->multicast_startup_query_count)
 877                 query->startup_sent++;
 878
 879         br_multicast_send_query(port->br, port, query);
 880
 881 out:
 882         spin_unlock(&br->multicast_lock);
 883 }
 884
 885 static void br_ip4_multicast_port_query_expired(unsigned long data)
 886 {
 887         struct net_bridge_port *port = (void *)data;
 888
 889         br_multicast_port_query_expired(port, &port->ip4_own_query);
 890 }
 891
 892 #if IS_ENABLED(CONFIG_IPV6)
 893 static void br_ip6_multicast_port_query_expired(unsigned long data)
 894 {
 895         struct net_bridge_port *port = (void *)data;
 896
 897         br_multicast_port_query_expired(port, &port->ip6_own_query);
 898 }
 899 #endif
 900
 901 void br_multicast_add_port(struct net_bridge_port *port)
 902 {
 903         port->multicast_router = 1;
 904
 905         setup_timer(&port->multicast_router_timer, br_multicast_router_expired,
 906                     (unsigned long)port);
 907         setup_timer(&port->ip4_own_query.timer,
 908                     br_ip4_multicast_port_query_expired, (unsigned long)port);
 909 #if IS_ENABLED(CONFIG_IPV6)
 910         setup_timer(&port->ip6_own_query.timer,
 911                     br_ip6_multicast_port_query_expired, (unsigned long)port);
 912 #endif
 913 }
 914
 915 void br_multicast_del_port(struct net_bridge_port *port)
 916 {
 917         del_timer_sync(&port->multicast_router_timer);
 918 }
 919
 920 static void br_multicast_enable(struct bridge_mcast_own_query *query)
 921 {
 922         query->startup_sent = 0;
 923
 924         if (try_to_del_timer_sync(&query->timer) >= 0 ||
 925             del_timer(&query->timer))
 926                 mod_timer(&query->timer, jiffies);
 927 }
 928
 929 void br_multicast_enable_port(struct net_bridge_port *port)
 930 {
 931         struct net_bridge *br = port->br;
 932
 933         spin_lock(&br->multicast_lock);
 934         if (br->multicast_disabled || !netif_running(br->dev))
 935                 goto out;
 936
 937         br_multicast_enable(&port->ip4_own_query);
 938 #if IS_ENABLED(CONFIG_IPV6)
 939         br_multicast_enable(&port->ip6_own_query);
 940 #endif
 941         if (port->multicast_router == 2 && hlist_unhashed(&port->rlist))
 942                 br_multicast_add_router(br, port);
 943
 944 out:
 945         spin_unlock(&br->multicast_lock);
 946 }
 947
 948 void br_multicast_disable_port(struct net_bridge_port *port)
 949 {
 950         struct net_bridge *br = port->br;
 951         struct net_bridge_port_group *pg;
 952         struct hlist_node *n;
 953
 954         spin_lock(&br->multicast_lock);
 955         hlist_for_each_entry_safe(pg, n, &port->mglist, mglist)
 956                 br_multicast_del_pg(br, pg);
 957
 958         if (!hlist_unhashed(&port->rlist))
 959                 hlist_del_init_rcu(&port->rlist);
 960         del_timer(&port->multicast_router_timer);
 961         del_timer(&port->ip4_own_query.timer);
 962 #if IS_ENABLED(CONFIG_IPV6)
 963         del_timer(&port->ip6_own_query.timer);
 964 #endif
 965         spin_unlock(&br->multicast_lock);
 966 }
 967
 968 static int br_ip4_multicast_igmp3_report(struct net_bridge *br,
 969                                          struct net_bridge_port *port,
 970                                          struct sk_buff *skb,
 971                                          u16 vid)
 972 {
 973         struct igmpv3_report *ih;
 974         struct igmpv3_grec *grec;
 975         int i;
 976         int len;
 977         int num;
 978         int type;
 979         int err = 0;
 980         __be32 group;
 981
 982         if (!pskb_may_pull(skb, sizeof(*ih)))
 983                 return -EINVAL;
 984
 985         ih = igmpv3_report_hdr(skb);
 986         num = ntohs(ih->ngrec);
 987         len = sizeof(*ih);
 988
 989         for (i = 0; i < num; i++) {
 990                 len += sizeof(*grec);
 991                 if (!pskb_may_pull(skb, len))
 992                         return -EINVAL;
 993
 994                 grec = (void *)(skb->data + len - sizeof(*grec));
 995                 group = grec->grec_mca;
 996                 type = grec->grec_type;
 997
 998                 len += ntohs(grec->grec_nsrcs) * 4;
 999                 if (!pskb_may_pull(skb, len))
1000                         return -EINVAL;
1001
1002                 /* We treat this as an IGMPv2 report for now. */
1003                 switch (type) {
1004                 case IGMPV3_MODE_IS_INCLUDE:
1005                 case IGMPV3_MODE_IS_EXCLUDE:
1006                 case IGMPV3_CHANGE_TO_INCLUDE:
1007                 case IGMPV3_CHANGE_TO_EXCLUDE:
1008                 case IGMPV3_ALLOW_NEW_SOURCES:
1009                 case IGMPV3_BLOCK_OLD_SOURCES:
1010                         break;
1011
1012                 default:
1013                         continue;
1014                 }
1015
1016                 err = br_ip4_multicast_add_group(br, port, group, vid);
1017                 if (err)
1018                         break;
1019         }
1020
1021         return err;
1022 }
1023
1024 #if IS_ENABLED(CONFIG_IPV6)
1025 static int br_ip6_multicast_mld2_report(struct net_bridge *br,
1026                                         struct net_bridge_port *port,
1027                                         struct sk_buff *skb,
1028                                         u16 vid)
1029 {
1030         struct icmp6hdr *icmp6h;
1031         struct mld2_grec *grec;
1032         int i;
1033         int len;
1034         int num;
1035         int err = 0;
1036
1037         if (!pskb_may_pull(skb, sizeof(*icmp6h)))
1038                 return -EINVAL;
1039
1040         icmp6h = icmp6_hdr(skb);
1041         num = ntohs(icmp6h->icmp6_dataun.un_data16[1]);
1042         len = sizeof(*icmp6h);
1043
1044         for (i = 0; i < num; i++) {
1045                 __be16 *nsrcs, _nsrcs;
1046
1047                 nsrcs = skb_header_pointer(skb,
1048                                            len + offsetof(struct mld2_grec,
1049                                                           grec_nsrcs),
1050                                            sizeof(_nsrcs), &_nsrcs);
1051                 if (!nsrcs)
1052                         return -EINVAL;
1053
1054                 if (!pskb_may_pull(skb,
1055                                    len + sizeof(*grec) +
1056                                    sizeof(struct in6_addr) * ntohs(*nsrcs)))
1057                         return -EINVAL;
1058
1059                 grec = (struct mld2_grec *)(skb->data + len);
1060                 len += sizeof(*grec) +
1061                        sizeof(struct in6_addr) * ntohs(*nsrcs);
1062
1063                 /* We treat these as MLDv1 reports for now. */
1064                 switch (grec->grec_type) {
1065                 case MLD2_MODE_IS_INCLUDE:
1066                 case MLD2_MODE_IS_EXCLUDE:
1067                 case MLD2_CHANGE_TO_INCLUDE:
1068                 case MLD2_CHANGE_TO_EXCLUDE:
1069                 case MLD2_ALLOW_NEW_SOURCES:
1070                 case MLD2_BLOCK_OLD_SOURCES:
1071                         break;
1072
1073                 default:
1074                         continue;
1075                 }
1076
1077                 err = br_ip6_multicast_add_group(br, port, &grec->grec_mca,
1078                                                  vid);
1079                 if (err)
1080                         break;
1081         }
1082
1083         return err;
1084 }
1085 #endif
1086
1087 static bool br_ip4_multicast_select_querier(struct net_bridge *br,
1088                                             struct net_bridge_port *port,
1089                                             __be32 saddr)
1090 {
1091         if (!timer_pending(&br->ip4_own_query.timer) &&
1092             !timer_pending(&br->ip4_other_query.timer))
1093                 goto update;
1094
1095         if (!br->ip4_querier.addr.u.ip4)
1096                 goto update;
1097
1098         if (ntohl(saddr) <= ntohl(br->ip4_querier.addr.u.ip4))
1099                 goto update;
1100
1101         return false;
1102
1103 update:
1104         br->ip4_querier.addr.u.ip4 = saddr;
1105
1106         /* update protected by general multicast_lock by caller */
1107         rcu_assign_pointer(br->ip4_querier.port, port);
1108
1109         return true;
1110 }
1111
1112 #if IS_ENABLED(CONFIG_IPV6)
1113 static bool br_ip6_multicast_select_querier(struct net_bridge *br,
1114                                             struct net_bridge_port *port,
1115                                             struct in6_addr *saddr)
1116 {
1117         if (!timer_pending(&br->ip6_own_query.timer) &&
1118             !timer_pending(&br->ip6_other_query.timer))
1119                 goto update;
1120
1121         if (ipv6_addr_cmp(saddr, &br->ip6_querier.addr.u.ip6) <= 0)
1122                 goto update;
1123
1124         return false;
1125
1126 update:
1127         br->ip6_querier.addr.u.ip6 = *saddr;
1128
1129         /* update protected by general multicast_lock by caller */
1130         rcu_assign_pointer(br->ip6_querier.port, port);
1131
1132         return true;
1133 }
1134 #endif
1135
1136 static bool br_multicast_select_querier(struct net_bridge *br,
1137                                         struct net_bridge_port *port,
1138                                         struct br_ip *saddr)
1139 {
1140         switch (saddr->proto) {
1141         case htons(ETH_P_IP):
1142                 return br_ip4_multicast_select_querier(br, port, saddr->u.ip4);
1143 #if IS_ENABLED(CONFIG_IPV6)
1144         case htons(ETH_P_IPV6):
1145                 return br_ip6_multicast_select_querier(br, port, &saddr->u.ip6);
1146 #endif
1147         }
1148
1149         return false;
1150 }
1151
1152 static void
1153 br_multicast_update_query_timer(struct net_bridge *br,
1154                                 struct bridge_mcast_other_query *query,
1155                                 unsigned long max_delay)
1156 {
1157         if (!timer_pending(&query->timer))
1158                 query->delay_time = jiffies + max_delay;
1159
1160         mod_timer(&query->timer, jiffies + br->multicast_querier_interval);
1161 }
1162
1163 /*
1164  * Add port to router_list
1165  *  list is maintained ordered by pointer value
1166  *  and locked by br->multicast_lock and RCU
1167  */
1168 static void br_multicast_add_router(struct net_bridge *br,
1169                                     struct net_bridge_port *port)
1170 {
1171         struct net_bridge_port *p;
1172         struct hlist_node *slot = NULL;
1173
1174         if (!hlist_unhashed(&port->rlist))
1175                 return;
1176
1177         hlist_for_each_entry(p, &br->router_list, rlist) {
1178                 if ((unsigned long) port >= (unsigned long) p)
1179                         break;
1180                 slot = &p->rlist;
1181         }
1182
1183         if (slot)
1184                 hlist_add_behind_rcu(&port->rlist, slot);
1185         else
1186                 hlist_add_head_rcu(&port->rlist, &br->router_list);
1187 }
1188
1189 static void br_multicast_mark_router(struct net_bridge *br,
1190                                      struct net_bridge_port *port)
1191 {
1192         unsigned long now = jiffies;
1193
1194         if (!port) {
1195                 if (br->multicast_router == 1)
1196                         mod_timer(&br->multicast_router_timer,
1197                                   now + br->multicast_querier_interval);
1198                 return;
1199         }
1200
1201         if (port->multicast_router != 1)
1202                 return;
1203
1204         br_multicast_add_router(br, port);
1205
1206         mod_timer(&port->multicast_router_timer,
1207                   now + br->multicast_querier_interval);
1208 }
1209
1210 static void br_multicast_query_received(struct net_bridge *br,
1211                                         struct net_bridge_port *port,
1212                                         struct bridge_mcast_other_query *query,
1213                                         struct br_ip *saddr,
1214                                         unsigned long max_delay)
1215 {
1216         if (!br_multicast_select_querier(br, port, saddr))
1217                 return;
1218
1219         br_multicast_update_query_timer(br, query, max_delay);
1220         br_multicast_mark_router(br, port);
1221 }
1222
1223 static int br_ip4_multicast_query(struct net_bridge *br,
1224                                   struct net_bridge_port *port,
1225                                   struct sk_buff *skb,
1226                                   u16 vid)
1227 {
1228         const struct iphdr *iph = ip_hdr(skb);
1229         struct igmphdr *ih = igmp_hdr(skb);
1230         struct net_bridge_mdb_entry *mp;
1231         struct igmpv3_query *ih3;
1232         struct net_bridge_port_group *p;
1233         struct net_bridge_port_group __rcu **pp;
1234         struct br_ip saddr;
1235         unsigned long max_delay;
1236         unsigned long now = jiffies;
1237         __be32 group;
1238         int err = 0;
1239
1240         spin_lock(&br->multicast_lock);
1241         if (!netif_running(br->dev) ||
1242             (port && port->state == BR_STATE_DISABLED))
1243                 goto out;
1244
1245         group = ih->group;
1246
1247         if (skb->len == sizeof(*ih)) {
1248                 max_delay = ih->code * (HZ / IGMP_TIMER_SCALE);
1249
1250                 if (!max_delay) {
1251                         max_delay = 10 * HZ;
1252                         group = 0;
1253                 }
1254         } else {
1255                 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query))) {
1256                         err = -EINVAL;
1257                         goto out;
1258                 }
1259
1260                 ih3 = igmpv3_query_hdr(skb);
1261                 if (ih3->nsrcs)
1262                         goto out;
1263
1264                 max_delay = ih3->code ?
1265                             IGMPV3_MRC(ih3->code) * (HZ / IGMP_TIMER_SCALE) : 1;
1266         }
1267
1268         /* RFC2236+RFC3376 (IGMPv2+IGMPv3) require the multicast link layer
1269          * all-systems destination addresses (224.0.0.1) for general queries
1270          */
1271         if (!group && iph->daddr != htonl(INADDR_ALLHOSTS_GROUP)) {
1272                 err = -EINVAL;
1273                 goto out;
1274         }
1275
1276         if (!group) {
1277                 saddr.proto = htons(ETH_P_IP);
1278                 saddr.u.ip4 = iph->saddr;
1279
1280                 br_multicast_query_received(br, port, &br->ip4_other_query,
1281                                             &saddr, max_delay);
1282                 goto out;
1283         }
1284
1285         mp = br_mdb_ip4_get(mlock_dereference(br->mdb, br), group, vid);
1286         if (!mp)
1287                 goto out;
1288
1289         max_delay *= br->multicast_last_member_count;
1290
1291         if (mp->mglist &&
1292             (timer_pending(&mp->timer) ?
1293              time_after(mp->timer.expires, now + max_delay) :
1294              try_to_del_timer_sync(&mp->timer) >= 0))
1295                 mod_timer(&mp->timer, now + max_delay);
1296
1297         for (pp = &mp->ports;
1298              (p = mlock_dereference(*pp, br)) != NULL;
1299              pp = &p->next) {
1300                 if (timer_pending(&p->timer) ?
1301                     time_after(p->timer.expires, now + max_delay) :
1302                     try_to_del_timer_sync(&p->timer) >= 0)
1303                         mod_timer(&p->timer, now + max_delay);
1304         }
1305
1306 out:
1307         spin_unlock(&br->multicast_lock);
1308         return err;
1309 }
1310
1311 #if IS_ENABLED(CONFIG_IPV6)
1312 static int br_ip6_multicast_query(struct net_bridge *br,
1313                                   struct net_bridge_port *port,
1314                                   struct sk_buff *skb,
1315                                   u16 vid)
1316 {
1317         const struct ipv6hdr *ip6h = ipv6_hdr(skb);
1318         struct mld_msg *mld;
1319         struct net_bridge_mdb_entry *mp;
1320         struct mld2_query *mld2q;
1321         struct net_bridge_port_group *p;
1322         struct net_bridge_port_group __rcu **pp;
1323         struct br_ip saddr;
1324         unsigned long max_delay;
1325         unsigned long now = jiffies;
1326         const struct in6_addr *group = NULL;
1327         bool is_general_query;
1328         int err = 0;
1329
1330         spin_lock(&br->multicast_lock);
1331         if (!netif_running(br->dev) ||
1332             (port && port->state == BR_STATE_DISABLED))
1333                 goto out;
1334
1335         /* RFC2710+RFC3810 (MLDv1+MLDv2) require link-local source addresses */
1336         if (!(ipv6_addr_type(&ip6h->saddr) & IPV6_ADDR_LINKLOCAL)) {
1337                 err = -EINVAL;
1338                 goto out;
1339         }
1340
1341         if (skb->len == sizeof(*mld)) {
1342                 if (!pskb_may_pull(skb, sizeof(*mld))) {
1343                         err = -EINVAL;
1344                         goto out;
1345                 }
1346                 mld = (struct mld_msg *) icmp6_hdr(skb);
1347                 max_delay = msecs_to_jiffies(ntohs(mld->mld_maxdelay));
1348                 if (max_delay)
1349                         group = &mld->mld_mca;
1350         } else {
1351                 if (!pskb_may_pull(skb, sizeof(*mld2q))) {
1352                         err = -EINVAL;
1353                         goto out;
1354                 }
1355                 mld2q = (struct mld2_query *)icmp6_hdr(skb);
1356                 if (!mld2q->mld2q_nsrcs)
1357                         group = &mld2q->mld2q_mca;
1358
1359                 max_delay = max(msecs_to_jiffies(mldv2_mrc(mld2q)), 1UL);
1360         }
1361
1362         is_general_query = group && ipv6_addr_any(group);
1363
1364         /* RFC2710+RFC3810 (MLDv1+MLDv2) require the multicast link layer
1365          * all-nodes destination address (ff02::1) for general queries
1366          */
1367         if (is_general_query && !ipv6_addr_is_ll_all_nodes(&ip6h->daddr)) {
1368                 err = -EINVAL;
1369                 goto out;
1370         }
1371
1372         if (is_general_query) {
1373                 saddr.proto = htons(ETH_P_IPV6);
1374                 saddr.u.ip6 = ip6h->saddr;
1375
1376                 br_multicast_query_received(br, port, &br->ip6_other_query,
1377                                             &saddr, max_delay);
1378                 goto out;
1379         } else if (!group) {
1380                 goto out;
1381         }
1382
1383         mp = br_mdb_ip6_get(mlock_dereference(br->mdb, br), group, vid);
1384         if (!mp)
1385                 goto out;
1386
1387         max_delay *= br->multicast_last_member_count;
1388         if (mp->mglist &&
1389             (timer_pending(&mp->timer) ?
1390              time_after(mp->timer.expires, now + max_delay) :
1391              try_to_del_timer_sync(&mp->timer) >= 0))
1392                 mod_timer(&mp->timer, now + max_delay);
1393
1394         for (pp = &mp->ports;
1395              (p = mlock_dereference(*pp, br)) != NULL;
1396              pp = &p->next) {
1397                 if (timer_pending(&p->timer) ?
1398                     time_after(p->timer.expires, now + max_delay) :
1399                     try_to_del_timer_sync(&p->timer) >= 0)
1400                         mod_timer(&p->timer, now + max_delay);
1401         }
1402
1403 out:
1404         spin_unlock(&br->multicast_lock);
1405         return err;
1406 }
1407 #endif
1408
1409 static void
1410 br_multicast_leave_group(struct net_bridge *br,
1411                          struct net_bridge_port *port,
1412                          struct br_ip *group,
1413                          struct bridge_mcast_other_query *other_query,
1414                          struct bridge_mcast_own_query *own_query)
1415 {
1416         struct net_bridge_mdb_htable *mdb;
1417         struct net_bridge_mdb_entry *mp;
1418         struct net_bridge_port_group *p;
1419         unsigned long now;
1420         unsigned long time;
1421
1422         spin_lock(&br->multicast_lock);
1423         if (!netif_running(br->dev) ||
1424             (port && port->state == BR_STATE_DISABLED) ||
1425             timer_pending(&other_query->timer))
1426                 goto out;
1427
1428         mdb = mlock_dereference(br->mdb, br);
1429         mp = br_mdb_ip_get(mdb, group);
1430         if (!mp)
1431                 goto out;
1432
1433         if (br->multicast_querier) {
1434                 __br_multicast_send_query(br, port, &mp->addr);
1435
1436                 time = jiffies + br->multicast_last_member_count *
1437                                  br->multicast_last_member_interval;
1438
1439                 mod_timer(&own_query->timer, time);
1440
1441                 for (p = mlock_dereference(mp->ports, br);
1442                      p != NULL;
1443                      p = mlock_dereference(p->next, br)) {
1444                         if (p->port != port)
1445                                 continue;
1446
1447                         if (!hlist_unhashed(&p->mglist) &&
1448                             (timer_pending(&p->timer) ?
1449                              time_after(p->timer.expires, time) :
1450                              try_to_del_timer_sync(&p->timer) >= 0)) {
1451                                 mod_timer(&p->timer, time);
1452                         }
1453
1454                         break;
1455                 }
1456         }
1457
1458         if (port && (port->flags & BR_MULTICAST_FAST_LEAVE)) {
1459                 struct net_bridge_port_group __rcu **pp;
1460
1461                 for (pp = &mp->ports;
1462                      (p = mlock_dereference(*pp, br)) != NULL;
1463                      pp = &p->next) {
1464                         if (p->port != port)
1465                                 continue;
1466
1467                         rcu_assign_pointer(*pp, p->next);
1468                         hlist_del_init(&p->mglist);
1469                         del_timer(&p->timer);
1470                         call_rcu_bh(&p->rcu, br_multicast_free_pg);
1471                         br_mdb_notify(br->dev, port, group, RTM_DELMDB);
1472
1473                         if (!mp->ports && !mp->mglist &&
1474                             netif_running(br->dev))
1475                                 mod_timer(&mp->timer, jiffies);
1476                 }
1477                 goto out;
1478         }
1479
1480         now = jiffies;
1481         time = now + br->multicast_last_member_count *
1482                      br->multicast_last_member_interval;
1483
1484         if (!port) {
1485                 if (mp->mglist &&
1486                     (timer_pending(&mp->timer) ?
1487                      time_after(mp->timer.expires, time) :
1488                      try_to_del_timer_sync(&mp->timer) >= 0)) {
1489                         mod_timer(&mp->timer, time);
1490                 }
1491
1492                 goto out;
1493         }
1494
1495         for (p = mlock_dereference(mp->ports, br);
1496              p != NULL;
1497              p = mlock_dereference(p->next, br)) {
1498                 if (p->port != port)
1499                         continue;
1500
1501                 if (!hlist_unhashed(&p->mglist) &&
1502                     (timer_pending(&p->timer) ?
1503                      time_after(p->timer.expires, time) :
1504                      try_to_del_timer_sync(&p->timer) >= 0)) {
1505                         mod_timer(&p->timer, time);
1506                 }
1507
1508                 break;
1509         }
1510 out:
1511         spin_unlock(&br->multicast_lock);
1512 }
1513
1514 static void br_ip4_multicast_leave_group(struct net_bridge *br,
1515                                          struct net_bridge_port *port,
1516                                          __be32 group,
1517                                          __u16 vid)
1518 {
1519         struct br_ip br_group;
1520         struct bridge_mcast_own_query *own_query;
1521
1522         if (ipv4_is_local_multicast(group))
1523                 return;
1524
1525         own_query = port ? &port->ip4_own_query : &br->ip4_own_query;
1526
1527         br_group.u.ip4 = group;
1528         br_group.proto = htons(ETH_P_IP);
1529         br_group.vid = vid;
1530
1531         br_multicast_leave_group(br, port, &br_group, &br->ip4_other_query,
1532                                  own_query);
1533 }
1534
1535 #if IS_ENABLED(CONFIG_IPV6)
1536 static void br_ip6_multicast_leave_group(struct net_bridge *br,
1537                                          struct net_bridge_port *port,
1538                                          const struct in6_addr *group,
1539                                          __u16 vid)
1540 {
1541         struct br_ip br_group;
1542         struct bridge_mcast_own_query *own_query;
1543
1544         if (ipv6_addr_is_ll_all_nodes(group))
1545                 return;
1546
1547         own_query = port ? &port->ip6_own_query : &br->ip6_own_query;
1548
1549         br_group.u.ip6 = *group;
1550         br_group.proto = htons(ETH_P_IPV6);
1551         br_group.vid = vid;
1552
1553         br_multicast_leave_group(br, port, &br_group, &br->ip6_other_query,
1554                                  own_query);
1555 }
1556 #endif
1557
1558 static int br_multicast_ipv4_rcv(struct net_bridge *br,
1559                                  struct net_bridge_port *port,
1560                                  struct sk_buff *skb,
1561                                  u16 vid)
1562 {
1563         struct sk_buff *skb2 = skb;
1564         const struct iphdr *iph;
1565         struct igmphdr *ih;
1566         unsigned int len;
1567         unsigned int offset;
1568         int err;
1569
1570         /* We treat OOM as packet loss for now. */
1571         if (!pskb_may_pull(skb, sizeof(*iph)))
1572                 return -EINVAL;
1573
1574         iph = ip_hdr(skb);
1575
1576         if (iph->ihl < 5 || iph->version != 4)
1577                 return -EINVAL;
1578
1579         if (!pskb_may_pull(skb, ip_hdrlen(skb)))
1580                 return -EINVAL;
1581
1582         iph = ip_hdr(skb);
1583
1584         if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1585                 return -EINVAL;
1586
1587         if (iph->protocol != IPPROTO_IGMP) {
1588                 if (!ipv4_is_local_multicast(iph->daddr))
1589                         BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1590                 return 0;
1591         }
1592
1593         len = ntohs(iph->tot_len);
1594         if (skb->len < len || len < ip_hdrlen(skb))
1595                 return -EINVAL;
1596
1597         if (skb->len > len) {
1598                 skb2 = skb_clone(skb, GFP_ATOMIC);
1599                 if (!skb2)
1600                         return -ENOMEM;
1601
1602                 err = pskb_trim_rcsum(skb2, len);
1603                 if (err)
1604                         goto err_out;
1605         }
1606
1607         len -= ip_hdrlen(skb2);
1608         offset = skb_network_offset(skb2) + ip_hdrlen(skb2);
1609         __skb_pull(skb2, offset);
1610         skb_reset_transport_header(skb2);
1611
1612         err = -EINVAL;
1613         if (!pskb_may_pull(skb2, sizeof(*ih)))
1614                 goto out;
1615
1616         switch (skb2->ip_summed) {
1617         case CHECKSUM_COMPLETE:
1618                 if (!csum_fold(skb2->csum))
1619                         break;
1620                 /* fall through */
1621         case CHECKSUM_NONE:
1622                 skb2->csum = 0;
1623                 if (skb_checksum_complete(skb2))
1624                         goto out;
1625         }
1626
1627         err = 0;
1628
1629         BR_INPUT_SKB_CB(skb)->igmp = 1;
1630         ih = igmp_hdr(skb2);
1631
1632         switch (ih->type) {
1633         case IGMP_HOST_MEMBERSHIP_REPORT:
1634         case IGMPV2_HOST_MEMBERSHIP_REPORT:
1635                 BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1636                 err = br_ip4_multicast_add_group(br, port, ih->group, vid);
1637                 break;
1638         case IGMPV3_HOST_MEMBERSHIP_REPORT:
1639                 err = br_ip4_multicast_igmp3_report(br, port, skb2, vid);
1640                 break;
1641         case IGMP_HOST_MEMBERSHIP_QUERY:
1642                 err = br_ip4_multicast_query(br, port, skb2, vid);
1643                 break;
1644         case IGMP_HOST_LEAVE_MESSAGE:
1645                 br_ip4_multicast_leave_group(br, port, ih->group, vid);
1646                 break;
1647         }
1648
1649 out:
1650         __skb_push(skb2, offset);
1651 err_out:
1652         if (skb2 != skb)
1653                 kfree_skb(skb2);
1654         return err;
1655 }
1656
1657 #if IS_ENABLED(CONFIG_IPV6)
1658 static int br_multicast_ipv6_rcv(struct net_bridge *br,
1659                                  struct net_bridge_port *port,
1660                                  struct sk_buff *skb,
1661                                  u16 vid)
1662 {
1663         struct sk_buff *skb2;
1664         const struct ipv6hdr *ip6h;
1665         u8 icmp6_type;
1666         u8 nexthdr;
1667         __be16 frag_off;
1668         unsigned int len;
1669         int offset;
1670         int err;
1671
1672         if (!pskb_may_pull(skb, sizeof(*ip6h)))
1673                 return -EINVAL;
1674
1675         ip6h = ipv6_hdr(skb);
1676
1677         /*
1678          * We're interested in MLD messages only.
1679          *  - Version is 6
1680          *  - MLD has always Router Alert hop-by-hop option
1681          *  - But we do not support jumbrograms.
1682          */
1683         if (ip6h->version != 6)
1684                 return 0;
1685
1686         /* Prevent flooding this packet if there is no listener present */
1687         if (!ipv6_addr_is_ll_all_nodes(&ip6h->daddr))
1688                 BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1689
1690         if (ip6h->nexthdr != IPPROTO_HOPOPTS ||
1691             ip6h->payload_len == 0)
1692                 return 0;
1693
1694         len = ntohs(ip6h->payload_len) + sizeof(*ip6h);
1695         if (skb->len < len)
1696                 return -EINVAL;
1697
1698         nexthdr = ip6h->nexthdr;
1699         offset = ipv6_skip_exthdr(skb, sizeof(*ip6h), &nexthdr, &frag_off);
1700
1701         if (offset < 0 || nexthdr != IPPROTO_ICMPV6)
1702                 return 0;
1703
1704         /* Okay, we found ICMPv6 header */
1705         skb2 = skb_clone(skb, GFP_ATOMIC);
1706         if (!skb2)
1707                 return -ENOMEM;
1708
1709         err = -EINVAL;
1710         if (!pskb_may_pull(skb2, offset + sizeof(struct icmp6hdr)))
1711                 goto out;
1712
1713         len -= offset - skb_network_offset(skb2);
1714
1715         __skb_pull(skb2, offset);
1716         skb_reset_transport_header(skb2);
1717         skb_postpull_rcsum(skb2, skb_network_header(skb2),
1718                            skb_network_header_len(skb2));
1719
1720         icmp6_type = icmp6_hdr(skb2)->icmp6_type;
1721
1722         switch (icmp6_type) {
1723         case ICMPV6_MGM_QUERY:
1724         case ICMPV6_MGM_REPORT:
1725         case ICMPV6_MGM_REDUCTION:
1726         case ICMPV6_MLD2_REPORT:
1727                 break;
1728         default:
1729                 err = 0;
1730                 goto out;
1731         }
1732
1733         /* Okay, we found MLD message. Check further. */
1734         if (skb2->len > len) {
1735                 err = pskb_trim_rcsum(skb2, len);
1736                 if (err)
1737                         goto out;
1738                 err = -EINVAL;
1739         }
1740
1741         ip6h = ipv6_hdr(skb2);
1742
1743         switch (skb2->ip_summed) {
1744         case CHECKSUM_COMPLETE:
1745                 if (!csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, skb2->len,
1746                                         IPPROTO_ICMPV6, skb2->csum))
1747                         break;
1748                 /*FALLTHROUGH*/
1749         case CHECKSUM_NONE:
1750                 skb2->csum = ~csum_unfold(csum_ipv6_magic(&ip6h->saddr,
1751                                                         &ip6h->daddr,
1752                                                         skb2->len,
1753                                                         IPPROTO_ICMPV6, 0));
1754                 if (__skb_checksum_complete(skb2))
1755                         goto out;
1756         }
1757
1758         err = 0;
1759
1760         BR_INPUT_SKB_CB(skb)->igmp = 1;
1761
1762         switch (icmp6_type) {
1763         case ICMPV6_MGM_REPORT:
1764             {
1765                 struct mld_msg *mld;
1766                 if (!pskb_may_pull(skb2, sizeof(*mld))) {
1767                         err = -EINVAL;
1768                         goto out;
1769                 }
1770                 mld = (struct mld_msg *)skb_transport_header(skb2);
1771                 BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1772                 err = br_ip6_multicast_add_group(br, port, &mld->mld_mca, vid);
1773                 break;
1774             }
1775         case ICMPV6_MLD2_REPORT:
1776                 err = br_ip6_multicast_mld2_report(br, port, skb2, vid);
1777                 break;
1778         case ICMPV6_MGM_QUERY:
1779                 err = br_ip6_multicast_query(br, port, skb2, vid);
1780                 break;
1781         case ICMPV6_MGM_REDUCTION:
1782             {
1783                 struct mld_msg *mld;
1784                 if (!pskb_may_pull(skb2, sizeof(*mld))) {
1785                         err = -EINVAL;
1786                         goto out;
1787                 }
1788                 mld = (struct mld_msg *)skb_transport_header(skb2);
1789                 br_ip6_multicast_leave_group(br, port, &mld->mld_mca, vid);
1790             }
1791         }
1792
1793 out:
1794         kfree_skb(skb2);
1795         return err;
1796 }
1797 #endif
1798
1799 int br_multicast_rcv(struct net_bridge *br, struct net_bridge_port *port,
1800                      struct sk_buff *skb, u16 vid)
1801 {
1802         BR_INPUT_SKB_CB(skb)->igmp = 0;
1803         BR_INPUT_SKB_CB(skb)->mrouters_only = 0;
1804
1805         if (br->multicast_disabled)
1806                 return 0;
1807
1808         switch (skb->protocol) {
1809         case htons(ETH_P_IP):
1810                 return br_multicast_ipv4_rcv(br, port, skb, vid);
1811 #if IS_ENABLED(CONFIG_IPV6)
1812         case htons(ETH_P_IPV6):
1813                 return br_multicast_ipv6_rcv(br, port, skb, vid);
1814 #endif
1815         }
1816
1817         return 0;
1818 }
1819
1820 static void br_multicast_query_expired(struct net_bridge *br,
1821                                        struct bridge_mcast_own_query *query,
1822                                        struct bridge_mcast_querier *querier)
1823 {
1824         spin_lock(&br->multicast_lock);
1825         if (query->startup_sent < br->multicast_startup_query_count)
1826                 query->startup_sent++;
1827
1828         RCU_INIT_POINTER(querier->port, NULL);
1829         br_multicast_send_query(br, NULL, query);
1830         spin_unlock(&br->multicast_lock);
1831 }
1832
1833 static void br_ip4_multicast_query_expired(unsigned long data)
1834 {
1835         struct net_bridge *br = (void *)data;
1836
1837         br_multicast_query_expired(br, &br->ip4_own_query, &br->ip4_querier);
1838 }
1839
1840 #if IS_ENABLED(CONFIG_IPV6)
1841 static void br_ip6_multicast_query_expired(unsigned long data)
1842 {
1843         struct net_bridge *br = (void *)data;
1844
1845         br_multicast_query_expired(br, &br->ip6_own_query, &br->ip6_querier);
1846 }
1847 #endif
1848
1849 void br_multicast_init(struct net_bridge *br)
1850 {
1851         br->hash_elasticity = 4;
1852         br->hash_max = 512;
1853
1854         br->multicast_router = 1;
1855         br->multicast_querier = 0;
1856         br->multicast_query_use_ifaddr = 0;
1857         br->multicast_last_member_count = 2;
1858         br->multicast_startup_query_count = 2;
1859
1860         br->multicast_last_member_interval = HZ;
1861         br->multicast_query_response_interval = 10 * HZ;
1862         br->multicast_startup_query_interval = 125 * HZ / 4;
1863         br->multicast_query_interval = 125 * HZ;
1864         br->multicast_querier_interval = 255 * HZ;
1865         br->multicast_membership_interval = 260 * HZ;
1866
1867         br->ip4_other_query.delay_time = 0;
1868         br->ip4_querier.port = NULL;
1869 #if IS_ENABLED(CONFIG_IPV6)
1870         br->ip6_other_query.delay_time = 0;
1871         br->ip6_querier.port = NULL;
1872 #endif
1873
1874         spin_lock_init(&br->multicast_lock);
1875         setup_timer(&br->multicast_router_timer,
1876                     br_multicast_local_router_expired, 0);
1877         setup_timer(&br->ip4_other_query.timer,
1878                     br_ip4_multicast_querier_expired, (unsigned long)br);
1879         setup_timer(&br->ip4_own_query.timer, br_ip4_multicast_query_expired,
1880                     (unsigned long)br);
1881 #if IS_ENABLED(CONFIG_IPV6)
1882         setup_timer(&br->ip6_other_query.timer,
1883                     br_ip6_multicast_querier_expired, (unsigned long)br);
1884         setup_timer(&br->ip6_own_query.timer, br_ip6_multicast_query_expired,
1885                     (unsigned long)br);
1886 #endif
1887 }
1888
1889 static void __br_multicast_open(struct net_bridge *br,
1890                                 struct bridge_mcast_own_query *query)
1891 {
1892         query->startup_sent = 0;
1893
1894         if (br->multicast_disabled)
1895                 return;
1896
1897         mod_timer(&query->timer, jiffies);
1898 }
1899
1900 void br_multicast_open(struct net_bridge *br)
1901 {
1902         __br_multicast_open(br, &br->ip4_own_query);
1903 #if IS_ENABLED(CONFIG_IPV6)
1904         __br_multicast_open(br, &br->ip6_own_query);
1905 #endif
1906 }
1907
1908 void br_multicast_stop(struct net_bridge *br)
1909 {
1910         struct net_bridge_mdb_htable *mdb;
1911         struct net_bridge_mdb_entry *mp;
1912         struct hlist_node *n;
1913         u32 ver;
1914         int i;
1915
1916         del_timer_sync(&br->multicast_router_timer);
1917         del_timer_sync(&br->ip4_other_query.timer);
1918         del_timer_sync(&br->ip4_own_query.timer);
1919 #if IS_ENABLED(CONFIG_IPV6)
1920         del_timer_sync(&br->ip6_other_query.timer);
1921         del_timer_sync(&br->ip6_own_query.timer);
1922 #endif
1923
1924         spin_lock_bh(&br->multicast_lock);
1925         mdb = mlock_dereference(br->mdb, br);
1926         if (!mdb)
1927                 goto out;
1928
1929         br->mdb = NULL;
1930
1931         ver = mdb->ver;
1932         for (i = 0; i < mdb->max; i++) {
1933                 hlist_for_each_entry_safe(mp, n, &mdb->mhash[i],
1934                                           hlist[ver]) {
1935                         del_timer(&mp->timer);
1936                         call_rcu_bh(&mp->rcu, br_multicast_free_group);
1937                 }
1938         }
1939
1940         if (mdb->old) {
1941                 spin_unlock_bh(&br->multicast_lock);
1942                 rcu_barrier_bh();
1943                 spin_lock_bh(&br->multicast_lock);
1944                 WARN_ON(mdb->old);
1945         }
1946
1947         mdb->old = mdb;
1948         call_rcu_bh(&mdb->rcu, br_mdb_free);
1949
1950 out:
1951         spin_unlock_bh(&br->multicast_lock);
1952 }
1953
1954 int br_multicast_set_router(struct net_bridge *br, unsigned long val)
1955 {
1956         int err = -ENOENT;
1957
1958         spin_lock_bh(&br->multicast_lock);
1959         if (!netif_running(br->dev))
1960                 goto unlock;
1961
1962         switch (val) {
1963         case 0:
1964         case 2:
1965                 del_timer(&br->multicast_router_timer);
1966                 /* fall through */
1967         case 1:
1968                 br->multicast_router = val;
1969                 err = 0;
1970                 break;
1971
1972         default:
1973                 err = -EINVAL;
1974                 break;
1975         }
1976
1977 unlock:
1978         spin_unlock_bh(&br->multicast_lock);
1979
1980         return err;
1981 }
1982
1983 int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
1984 {
1985         struct net_bridge *br = p->br;
1986         int err = -ENOENT;
1987
1988         spin_lock(&br->multicast_lock);
1989         if (!netif_running(br->dev) || p->state == BR_STATE_DISABLED)
1990                 goto unlock;
1991
1992         switch (val) {
1993         case 0:
1994         case 1:
1995         case 2:
1996                 p->multicast_router = val;
1997                 err = 0;
1998
1999                 if (val < 2 && !hlist_unhashed(&p->rlist))
2000                         hlist_del_init_rcu(&p->rlist);
2001
2002                 if (val == 1)
2003                         break;
2004
2005                 del_timer(&p->multicast_router_timer);
2006
2007                 if (val == 0)
2008                         break;
2009
2010                 br_multicast_add_router(br, p);
2011                 break;
2012
2013         default:
2014                 err = -EINVAL;
2015                 break;
2016         }
2017
2018 unlock:
2019         spin_unlock(&br->multicast_lock);
2020
2021         return err;
2022 }
2023
2024 static void br_multicast_start_querier(struct net_bridge *br,
2025                                        struct bridge_mcast_own_query *query)
2026 {
2027         struct net_bridge_port *port;
2028
2029         __br_multicast_open(br, query);
2030
2031         list_for_each_entry(port, &br->port_list, list) {
2032                 if (port->state == BR_STATE_DISABLED ||
2033                     port->state == BR_STATE_BLOCKING)
2034                         continue;
2035
2036                 if (query == &br->ip4_own_query)
2037                         br_multicast_enable(&port->ip4_own_query);
2038 #if IS_ENABLED(CONFIG_IPV6)
2039                 else
2040                         br_multicast_enable(&port->ip6_own_query);
2041 #endif
2042         }
2043 }
2044
2045 int br_multicast_toggle(struct net_bridge *br, unsigned long val)
2046 {
2047         int err = 0;
2048         struct net_bridge_mdb_htable *mdb;
2049
2050         spin_lock_bh(&br->multicast_lock);
2051         if (br->multicast_disabled == !val)
2052                 goto unlock;
2053
2054         br->multicast_disabled = !val;
2055         if (br->multicast_disabled)
2056                 goto unlock;
2057
2058         if (!netif_running(br->dev))
2059                 goto unlock;
2060
2061         mdb = mlock_dereference(br->mdb, br);
2062         if (mdb) {
2063                 if (mdb->old) {
2064                         err = -EEXIST;
2065 rollback:
2066                         br->multicast_disabled = !!val;
2067                         goto unlock;
2068                 }
2069
2070                 err = br_mdb_rehash(&br->mdb, mdb->max,
2071                                     br->hash_elasticity);
2072                 if (err)
2073                         goto rollback;
2074         }
2075
2076         br_multicast_start_querier(br, &br->ip4_own_query);
2077 #if IS_ENABLED(CONFIG_IPV6)
2078         br_multicast_start_querier(br, &br->ip6_own_query);
2079 #endif
2080
2081 unlock:
2082         spin_unlock_bh(&br->multicast_lock);
2083
2084         return err;
2085 }
2086
2087 int br_multicast_set_querier(struct net_bridge *br, unsigned long val)
2088 {
2089         unsigned long max_delay;
2090
2091         val = !!val;
2092
2093         spin_lock_bh(&br->multicast_lock);
2094         if (br->multicast_querier == val)
2095                 goto unlock;
2096
2097         br->multicast_querier = val;
2098         if (!val)
2099                 goto unlock;
2100
2101         max_delay = br->multicast_query_response_interval;
2102
2103         if (!timer_pending(&br->ip4_other_query.timer))
2104                 br->ip4_other_query.delay_time = jiffies + max_delay;
2105
2106         br_multicast_start_querier(br, &br->ip4_own_query);
2107
2108 #if IS_ENABLED(CONFIG_IPV6)
2109         if (!timer_pending(&br->ip6_other_query.timer))
2110                 br->ip6_other_query.delay_time = jiffies + max_delay;
2111
2112         br_multicast_start_querier(br, &br->ip6_own_query);
2113 #endif
2114
2115 unlock:
2116         spin_unlock_bh(&br->multicast_lock);
2117
2118         return 0;
2119 }
2120
2121 int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val)
2122 {
2123         int err = -ENOENT;
2124         u32 old;
2125         struct net_bridge_mdb_htable *mdb;
2126
2127         spin_lock_bh(&br->multicast_lock);
2128         if (!netif_running(br->dev))
2129                 goto unlock;
2130
2131         err = -EINVAL;
2132         if (!is_power_of_2(val))
2133                 goto unlock;
2134
2135         mdb = mlock_dereference(br->mdb, br);
2136         if (mdb && val < mdb->size)
2137                 goto unlock;
2138
2139         err = 0;
2140
2141         old = br->hash_max;
2142         br->hash_max = val;
2143
2144         if (mdb) {
2145                 if (mdb->old) {
2146                         err = -EEXIST;
2147 rollback:
2148                         br->hash_max = old;
2149                         goto unlock;
2150                 }
2151
2152                 err = br_mdb_rehash(&br->mdb, br->hash_max,
2153                                     br->hash_elasticity);
2154                 if (err)
2155                         goto rollback;
2156         }
2157
2158 unlock:
2159         spin_unlock_bh(&br->multicast_lock);
2160
2161         return err;
2162 }
2163
2164 /**
2165  * br_multicast_list_adjacent - Returns snooped multicast addresses
2166  * @dev:        The bridge port adjacent to which to retrieve addresses
2167  * @br_ip_list: The list to store found, snooped multicast IP addresses in
2168  *
2169  * Creates a list of IP addresses (struct br_ip_list) sensed by the multicast
2170  * snooping feature on all bridge ports of dev's bridge device, excluding
2171  * the addresses from dev itself.
2172  *
2173  * Returns the number of items added to br_ip_list.
2174  *
2175  * Notes:
2176  * - br_ip_list needs to be initialized by caller
2177  * - br_ip_list might contain duplicates in the end
2178  *   (needs to be taken care of by caller)
2179  * - br_ip_list needs to be freed by caller
2180  */
2181 int br_multicast_list_adjacent(struct net_device *dev,
2182                                struct list_head *br_ip_list)
2183 {
2184         struct net_bridge *br;
2185         struct net_bridge_port *port;
2186         struct net_bridge_port_group *group;
2187         struct br_ip_list *entry;
2188         int count = 0;
2189
2190         rcu_read_lock();
2191         if (!br_ip_list || !br_port_exists(dev))
2192                 goto unlock;
2193
2194         port = br_port_get_rcu(dev);
2195         if (!port || !port->br)
2196                 goto unlock;
2197
2198         br = port->br;
2199
2200         list_for_each_entry_rcu(port, &br->port_list, list) {
2201                 if (!port->dev || port->dev == dev)
2202                         continue;
2203
2204                 hlist_for_each_entry_rcu(group, &port->mglist, mglist) {
2205                         entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
2206                         if (!entry)
2207                                 goto unlock;
2208
2209                         entry->addr = group->addr;
2210                         list_add(&entry->list, br_ip_list);
2211                         count++;
2212                 }
2213         }
2214
2215 unlock:
2216         rcu_read_unlock();
2217         return count;
2218 }
2219 EXPORT_SYMBOL_GPL(br_multicast_list_adjacent);
2220
2221 /**
2222  * br_multicast_has_querier_anywhere - Checks for a querier on a bridge
2223  * @dev: The bridge port providing the bridge on which to check for a querier
2224  * @proto: The protocol family to check for: IGMP -> ETH_P_IP, MLD -> ETH_P_IPV6
2225  *
2226  * Checks whether the given interface has a bridge on top and if so returns
2227  * true if a valid querier exists anywhere on the bridged link layer.
2228  * Otherwise returns false.
2229  */
2230 bool br_multicast_has_querier_anywhere(struct net_device *dev, int proto)
2231 {
2232         struct net_bridge *br;
2233         struct net_bridge_port *port;
2234         struct ethhdr eth;
2235         bool ret = false;
2236
2237         rcu_read_lock();
2238         if (!br_port_exists(dev))
2239                 goto unlock;
2240
2241         port = br_port_get_rcu(dev);
2242         if (!port || !port->br)
2243                 goto unlock;
2244
2245         br = port->br;
2246
2247         memset(&eth, 0, sizeof(eth));
2248         eth.h_proto = htons(proto);
2249
2250         ret = br_multicast_querier_exists(br, &eth);
2251
2252 unlock:
2253         rcu_read_unlock();
2254         return ret;
2255 }
2256 EXPORT_SYMBOL_GPL(br_multicast_has_querier_anywhere);
2257
2258 /**
2259  * br_multicast_has_querier_adjacent - Checks for a querier behind a bridge port
2260  * @dev: The bridge port adjacent to which to check for a querier
2261  * @proto: The protocol family to check for: IGMP -> ETH_P_IP, MLD -> ETH_P_IPV6
2262  *
2263  * Checks whether the given interface has a bridge on top and if so returns
2264  * true if a selected querier is behind one of the other ports of this
2265  * bridge. Otherwise returns false.
2266  */
2267 bool br_multicast_has_querier_adjacent(struct net_device *dev, int proto)
2268 {
2269         struct net_bridge *br;
2270         struct net_bridge_port *port;
2271         bool ret = false;
2272
2273         rcu_read_lock();
2274         if (!br_port_exists(dev))
2275                 goto unlock;
2276
2277         port = br_port_get_rcu(dev);
2278         if (!port || !port->br)
2279                 goto unlock;
2280
2281         br = port->br;
2282
2283         switch (proto) {
2284         case ETH_P_IP:
2285                 if (!timer_pending(&br->ip4_other_query.timer) ||
2286                     rcu_dereference(br->ip4_querier.port) == port)
2287                         goto unlock;
2288                 break;
2289 #if IS_ENABLED(CONFIG_IPV6)
2290         case ETH_P_IPV6:
2291                 if (!timer_pending(&br->ip6_other_query.timer) ||
2292                     rcu_dereference(br->ip6_querier.port) == port)
2293                         goto unlock;
2294                 break;
2295 #endif
2296         default:
2297                 goto unlock;
2298         }
2299
2300         ret = true;
2301 unlock:
2302         rcu_read_unlock();
2303         return ret;
2304 }
2305 EXPORT_SYMBOL_GPL(br_multicast_has_querier_adjacent);