net/bridge/br_multicast.c

   1 /*
   2  * Bridge multicast support.
   3  *
   4  * Copyright (c) 2010 Herbert Xu <herbert@gondor.apana.org.au>
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the Free
   8  * Software Foundation; either version 2 of the License, or (at your option)
   9  * any later version.
  10  *
  11  */
  12
  13 #include <linux/err.h>
  14 #include <linux/if_ether.h>
  15 #include <linux/igmp.h>
  16 #include <linux/jhash.h>
  17 #include <linux/kernel.h>
  18 #include <linux/log2.h>
  19 #include <linux/netdevice.h>
  20 #include <linux/netfilter_bridge.h>
  21 #include <linux/random.h>
  22 #include <linux/rculist.h>
  23 #include <linux/skbuff.h>
  24 #include <linux/slab.h>
  25 #include <linux/timer.h>
  26 #include <net/ip.h>
  27 #if IS_ENABLED(CONFIG_IPV6)
  28 #include <net/ipv6.h>
  29 #include <net/mld.h>
  30 #include <net/addrconf.h>
  31 #include <net/ip6_checksum.h>
  32 #endif
  33
  34 #include "br_private.h"
  35
  36 #define mlock_dereference(X, br) \
  37         rcu_dereference_protected(X, lockdep_is_held(&br->multicast_lock))
  38
  39 static void br_multicast_start_querier(struct net_bridge *br);
  40
  41 #if IS_ENABLED(CONFIG_IPV6)
  42 static inline int ipv6_is_transient_multicast(const struct in6_addr *addr)
  43 {
  44         if (ipv6_addr_is_multicast(addr) && IPV6_ADDR_MC_FLAG_TRANSIENT(addr))
  45                 return 1;
  46         return 0;
  47 }
  48 #endif
  49
  50 static inline int br_ip_equal(const struct br_ip *a, const struct br_ip *b)
  51 {
  52         if (a->proto != b->proto)
  53                 return 0;
  54         switch (a->proto) {
  55         case htons(ETH_P_IP):
  56                 return a->u.ip4 == b->u.ip4;
  57 #if IS_ENABLED(CONFIG_IPV6)
  58         case htons(ETH_P_IPV6):
  59                 return ipv6_addr_equal(&a->u.ip6, &b->u.ip6);
  60 #endif
  61         }
  62         return 0;
  63 }
  64
  65 static inline int __br_ip4_hash(struct net_bridge_mdb_htable *mdb, __be32 ip)
  66 {
  67         return jhash_1word(mdb->secret, (__force u32)ip) & (mdb->max - 1);
  68 }
  69
  70 #if IS_ENABLED(CONFIG_IPV6)
  71 static inline int __br_ip6_hash(struct net_bridge_mdb_htable *mdb,
  72                                 const struct in6_addr *ip)
  73 {
  74         return jhash2((__force u32 *)ip->s6_addr32, 4, mdb->secret) & (mdb->max - 1);
  75 }
  76 #endif
  77
  78 static inline int br_ip_hash(struct net_bridge_mdb_htable *mdb,
  79                              struct br_ip *ip)
  80 {
  81         switch (ip->proto) {
  82         case htons(ETH_P_IP):
  83                 return __br_ip4_hash(mdb, ip->u.ip4);
  84 #if IS_ENABLED(CONFIG_IPV6)
  85         case htons(ETH_P_IPV6):
  86                 return __br_ip6_hash(mdb, &ip->u.ip6);
  87 #endif
  88         }
  89         return 0;
  90 }
  91
  92 static struct net_bridge_mdb_entry *__br_mdb_ip_get(
  93         struct net_bridge_mdb_htable *mdb, struct br_ip *dst, int hash)
  94 {
  95         struct net_bridge_mdb_entry *mp;
  96         struct hlist_node *p;
  97
  98         hlist_for_each_entry_rcu(mp, p, &mdb->mhash[hash], hlist[mdb->ver]) {
  99                 if (br_ip_equal(&mp->addr, dst))
 100                         return mp;
 101         }
 102
 103         return NULL;
 104 }
 105
 106 static struct net_bridge_mdb_entry *br_mdb_ip_get(
 107         struct net_bridge_mdb_htable *mdb, struct br_ip *dst)
 108 {
 109         if (!mdb)
 110                 return NULL;
 111
 112         return __br_mdb_ip_get(mdb, dst, br_ip_hash(mdb, dst));
 113 }
 114
 115 static struct net_bridge_mdb_entry *br_mdb_ip4_get(
 116         struct net_bridge_mdb_htable *mdb, __be32 dst)
 117 {
 118         struct br_ip br_dst;
 119
 120         br_dst.u.ip4 = dst;
 121         br_dst.proto = htons(ETH_P_IP);
 122
 123         return br_mdb_ip_get(mdb, &br_dst);
 124 }
 125
 126 #if IS_ENABLED(CONFIG_IPV6)
 127 static struct net_bridge_mdb_entry *br_mdb_ip6_get(
 128         struct net_bridge_mdb_htable *mdb, const struct in6_addr *dst)
 129 {
 130         struct br_ip br_dst;
 131
 132         br_dst.u.ip6 = *dst;
 133         br_dst.proto = htons(ETH_P_IPV6);
 134
 135         return br_mdb_ip_get(mdb, &br_dst);
 136 }
 137 #endif
 138
 139 struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br,
 140                                         struct sk_buff *skb)
 141 {
 142         struct net_bridge_mdb_htable *mdb = rcu_dereference(br->mdb);
 143         struct br_ip ip;
 144
 145         if (br->multicast_disabled)
 146                 return NULL;
 147
 148         if (BR_INPUT_SKB_CB(skb)->igmp)
 149                 return NULL;
 150
 151         ip.proto = skb->protocol;
 152
 153         switch (skb->protocol) {
 154         case htons(ETH_P_IP):
 155                 ip.u.ip4 = ip_hdr(skb)->daddr;
 156                 break;
 157 #if IS_ENABLED(CONFIG_IPV6)
 158         case htons(ETH_P_IPV6):
 159                 ip.u.ip6 = ipv6_hdr(skb)->daddr;
 160                 break;
 161 #endif
 162         default:
 163                 return NULL;
 164         }
 165
 166         return br_mdb_ip_get(mdb, &ip);
 167 }
 168
 169 static void br_mdb_free(struct rcu_head *head)
 170 {
 171         struct net_bridge_mdb_htable *mdb =
 172                 container_of(head, struct net_bridge_mdb_htable, rcu);
 173         struct net_bridge_mdb_htable *old = mdb->old;
 174
 175         mdb->old = NULL;
 176         kfree(old->mhash);
 177         kfree(old);
 178 }
 179
 180 static int br_mdb_copy(struct net_bridge_mdb_htable *new,
 181                        struct net_bridge_mdb_htable *old,
 182                        int elasticity)
 183 {
 184         struct net_bridge_mdb_entry *mp;
 185         struct hlist_node *p;
 186         int maxlen;
 187         int len;
 188         int i;
 189
 190         for (i = 0; i < old->max; i++)
 191                 hlist_for_each_entry(mp, p, &old->mhash[i], hlist[old->ver])
 192                         hlist_add_head(&mp->hlist[new->ver],
 193                                        &new->mhash[br_ip_hash(new, &mp->addr)]);
 194
 195         if (!elasticity)
 196                 return 0;
 197
 198         maxlen = 0;
 199         for (i = 0; i < new->max; i++) {
 200                 len = 0;
 201                 hlist_for_each_entry(mp, p, &new->mhash[i], hlist[new->ver])
 202                         len++;
 203                 if (len > maxlen)
 204                         maxlen = len;
 205         }
 206
 207         return maxlen > elasticity ? -EINVAL : 0;
 208 }
 209
 210 static void br_multicast_free_pg(struct rcu_head *head)
 211 {
 212         struct net_bridge_port_group *p =
 213                 container_of(head, struct net_bridge_port_group, rcu);
 214
 215         kfree(p);
 216 }
 217
 218 static void br_multicast_free_group(struct rcu_head *head)
 219 {
 220         struct net_bridge_mdb_entry *mp =
 221                 container_of(head, struct net_bridge_mdb_entry, rcu);
 222
 223         kfree(mp);
 224 }
 225
 226 static void br_multicast_group_expired(unsigned long data)
 227 {
 228         struct net_bridge_mdb_entry *mp = (void *)data;
 229         struct net_bridge *br = mp->br;
 230         struct net_bridge_mdb_htable *mdb;
 231
 232         spin_lock(&br->multicast_lock);
 233         if (!netif_running(br->dev) || timer_pending(&mp->timer))
 234                 goto out;
 235
 236         mp->mglist = false;
 237
 238         if (mp->ports)
 239                 goto out;
 240
 241         mdb = mlock_dereference(br->mdb, br);
 242
 243         hlist_del_rcu(&mp->hlist[mdb->ver]);
 244         mdb->size--;
 245
 246         call_rcu_bh(&mp->rcu, br_multicast_free_group);
 247
 248 out:
 249         spin_unlock(&br->multicast_lock);
 250 }
 251
 252 static void br_multicast_del_pg(struct net_bridge *br,
 253                                 struct net_bridge_port_group *pg)
 254 {
 255         struct net_bridge_mdb_htable *mdb;
 256         struct net_bridge_mdb_entry *mp;
 257         struct net_bridge_port_group *p;
 258         struct net_bridge_port_group __rcu **pp;
 259
 260         mdb = mlock_dereference(br->mdb, br);
 261
 262         mp = br_mdb_ip_get(mdb, &pg->addr);
 263         if (WARN_ON(!mp))
 264                 return;
 265
 266         for (pp = &mp->ports;
 267              (p = mlock_dereference(*pp, br)) != NULL;
 268              pp = &p->next) {
 269                 if (p != pg)
 270                         continue;
 271
 272                 rcu_assign_pointer(*pp, p->next);
 273                 hlist_del_init(&p->mglist);
 274                 del_timer(&p->timer);
 275                 call_rcu_bh(&p->rcu, br_multicast_free_pg);
 276
 277                 if (!mp->ports && !mp->mglist &&
 278                     netif_running(br->dev))
 279                         mod_timer(&mp->timer, jiffies);
 280
 281                 return;
 282         }
 283
 284         WARN_ON(1);
 285 }
 286
 287 static void br_multicast_port_group_expired(unsigned long data)
 288 {
 289         struct net_bridge_port_group *pg = (void *)data;
 290         struct net_bridge *br = pg->port->br;
 291
 292         spin_lock(&br->multicast_lock);
 293         if (!netif_running(br->dev) || timer_pending(&pg->timer) ||
 294             hlist_unhashed(&pg->mglist))
 295                 goto out;
 296
 297         br_multicast_del_pg(br, pg);
 298
 299 out:
 300         spin_unlock(&br->multicast_lock);
 301 }
 302
 303 static int br_mdb_rehash(struct net_bridge_mdb_htable __rcu **mdbp, int max,
 304                          int elasticity)
 305 {
 306         struct net_bridge_mdb_htable *old = rcu_dereference_protected(*mdbp, 1);
 307         struct net_bridge_mdb_htable *mdb;
 308         int err;
 309
 310         mdb = kmalloc(sizeof(*mdb), GFP_ATOMIC);
 311         if (!mdb)
 312                 return -ENOMEM;
 313
 314         mdb->max = max;
 315         mdb->old = old;
 316
 317         mdb->mhash = kzalloc(max * sizeof(*mdb->mhash), GFP_ATOMIC);
 318         if (!mdb->mhash) {
 319                 kfree(mdb);
 320                 return -ENOMEM;
 321         }
 322
 323         mdb->size = old ? old->size : 0;
 324         mdb->ver = old ? old->ver ^ 1 : 0;
 325
 326         if (!old || elasticity)
 327                 get_random_bytes(&mdb->secret, sizeof(mdb->secret));
 328         else
 329                 mdb->secret = old->secret;
 330
 331         if (!old)
 332                 goto out;
 333
 334         err = br_mdb_copy(mdb, old, elasticity);
 335         if (err) {
 336                 kfree(mdb->mhash);
 337                 kfree(mdb);
 338                 return err;
 339         }
 340
 341         call_rcu_bh(&mdb->rcu, br_mdb_free);
 342
 343 out:
 344         rcu_assign_pointer(*mdbp, mdb);
 345
 346         return 0;
 347 }
 348
 349 static struct sk_buff *br_ip4_multicast_alloc_query(struct net_bridge *br,
 350                                                     __be32 group)
 351 {
 352         struct sk_buff *skb;
 353         struct igmphdr *ih;
 354         struct ethhdr *eth;
 355         struct iphdr *iph;
 356
 357         skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*iph) +
 358                                                  sizeof(*ih) + 4);
 359         if (!skb)
 360                 goto out;
 361
 362         skb->protocol = htons(ETH_P_IP);
 363
 364         skb_reset_mac_header(skb);
 365         eth = eth_hdr(skb);
 366
 367         memcpy(eth->h_source, br->dev->dev_addr, 6);
 368         eth->h_dest[0] = 1;
 369         eth->h_dest[1] = 0;
 370         eth->h_dest[2] = 0x5e;
 371         eth->h_dest[3] = 0;
 372         eth->h_dest[4] = 0;
 373         eth->h_dest[5] = 1;
 374         eth->h_proto = htons(ETH_P_IP);
 375         skb_put(skb, sizeof(*eth));
 376
 377         skb_set_network_header(skb, skb->len);
 378         iph = ip_hdr(skb);
 379
 380         iph->version = 4;
 381         iph->ihl = 6;
 382         iph->tos = 0xc0;
 383         iph->tot_len = htons(sizeof(*iph) + sizeof(*ih) + 4);
 384         iph->id = 0;
 385         iph->frag_off = htons(IP_DF);
 386         iph->ttl = 1;
 387         iph->protocol = IPPROTO_IGMP;
 388         iph->saddr = 0;
 389         iph->daddr = htonl(INADDR_ALLHOSTS_GROUP);
 390         ((u8 *)&iph[1])[0] = IPOPT_RA;
 391         ((u8 *)&iph[1])[1] = 4;
 392         ((u8 *)&iph[1])[2] = 0;
 393         ((u8 *)&iph[1])[3] = 0;
 394         ip_send_check(iph);
 395         skb_put(skb, 24);
 396
 397         skb_set_transport_header(skb, skb->len);
 398         ih = igmp_hdr(skb);
 399         ih->type = IGMP_HOST_MEMBERSHIP_QUERY;
 400         ih->code = (group ? br->multicast_last_member_interval :
 401                             br->multicast_query_response_interval) /
 402                    (HZ / IGMP_TIMER_SCALE);
 403         ih->group = group;
 404         ih->csum = 0;
 405         ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr));
 406         skb_put(skb, sizeof(*ih));
 407
 408         __skb_pull(skb, sizeof(*eth));
 409
 410 out:
 411         return skb;
 412 }
 413
 414 #if IS_ENABLED(CONFIG_IPV6)
 415 static struct sk_buff *br_ip6_multicast_alloc_query(struct net_bridge *br,
 416                                                     const struct in6_addr *group)
 417 {
 418         struct sk_buff *skb;
 419         struct ipv6hdr *ip6h;
 420         struct mld_msg *mldq;
 421         struct ethhdr *eth;
 422         u8 *hopopt;
 423         unsigned long interval;
 424
 425         skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*ip6h) +
 426                                                  8 + sizeof(*mldq));
 427         if (!skb)
 428                 goto out;
 429
 430         skb->protocol = htons(ETH_P_IPV6);
 431
 432         /* Ethernet header */
 433         skb_reset_mac_header(skb);
 434         eth = eth_hdr(skb);
 435
 436         memcpy(eth->h_source, br->dev->dev_addr, 6);
 437         eth->h_proto = htons(ETH_P_IPV6);
 438         skb_put(skb, sizeof(*eth));
 439
 440         /* IPv6 header + HbH option */
 441         skb_set_network_header(skb, skb->len);
 442         ip6h = ipv6_hdr(skb);
 443
 444         *(__force __be32 *)ip6h = htonl(0x60000000);
 445         ip6h->payload_len = htons(8 + sizeof(*mldq));
 446         ip6h->nexthdr = IPPROTO_HOPOPTS;
 447         ip6h->hop_limit = 1;
 448         ipv6_addr_set(&ip6h->daddr, htonl(0xff020000), 0, 0, htonl(1));
 449         if (ipv6_dev_get_saddr(dev_net(br->dev), br->dev, &ip6h->daddr, 0,
 450                                &ip6h->saddr)) {
 451                 kfree_skb(skb);
 452                 return NULL;
 453         }
 454         ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest);
 455
 456         hopopt = (u8 *)(ip6h + 1);
 457         hopopt[0] = IPPROTO_ICMPV6;             /* next hdr */
 458         hopopt[1] = 0;                          /* length of HbH */
 459         hopopt[2] = IPV6_TLV_ROUTERALERT;       /* Router Alert */
 460         hopopt[3] = 2;                          /* Length of RA Option */
 461         hopopt[4] = 0;                          /* Type = 0x0000 (MLD) */
 462         hopopt[5] = 0;
 463         hopopt[6] = IPV6_TLV_PAD0;              /* Pad0 */
 464         hopopt[7] = IPV6_TLV_PAD0;              /* Pad0 */
 465
 466         skb_put(skb, sizeof(*ip6h) + 8);
 467
 468         /* ICMPv6 */
 469         skb_set_transport_header(skb, skb->len);
 470         mldq = (struct mld_msg *) icmp6_hdr(skb);
 471
 472         interval = ipv6_addr_any(group) ? br->multicast_last_member_interval :
 473                                           br->multicast_query_response_interval;
 474
 475         mldq->mld_type = ICMPV6_MGM_QUERY;
 476         mldq->mld_code = 0;
 477         mldq->mld_cksum = 0;
 478         mldq->mld_maxdelay = htons((u16)jiffies_to_msecs(interval));
 479         mldq->mld_reserved = 0;
 480         mldq->mld_mca = *group;
 481
 482         /* checksum */
 483         mldq->mld_cksum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
 484                                           sizeof(*mldq), IPPROTO_ICMPV6,
 485                                           csum_partial(mldq,
 486                                                        sizeof(*mldq), 0));
 487         skb_put(skb, sizeof(*mldq));
 488
 489         __skb_pull(skb, sizeof(*eth));
 490
 491 out:
 492         return skb;
 493 }
 494 #endif
 495
 496 static struct sk_buff *br_multicast_alloc_query(struct net_bridge *br,
 497                                                 struct br_ip *addr)
 498 {
 499         switch (addr->proto) {
 500         case htons(ETH_P_IP):
 501                 return br_ip4_multicast_alloc_query(br, addr->u.ip4);
 502 #if IS_ENABLED(CONFIG_IPV6)
 503         case htons(ETH_P_IPV6):
 504                 return br_ip6_multicast_alloc_query(br, &addr->u.ip6);
 505 #endif
 506         }
 507         return NULL;
 508 }
 509
 510 static struct net_bridge_mdb_entry *br_multicast_get_group(
 511         struct net_bridge *br, struct net_bridge_port *port,
 512         struct br_ip *group, int hash)
 513 {
 514         struct net_bridge_mdb_htable *mdb;
 515         struct net_bridge_mdb_entry *mp;
 516         struct hlist_node *p;
 517         unsigned int count = 0;
 518         unsigned int max;
 519         int elasticity;
 520         int err;
 521
 522         mdb = rcu_dereference_protected(br->mdb, 1);
 523         hlist_for_each_entry(mp, p, &mdb->mhash[hash], hlist[mdb->ver]) {
 524                 count++;
 525                 if (unlikely(br_ip_equal(group, &mp->addr)))
 526                         return mp;
 527         }
 528
 529         elasticity = 0;
 530         max = mdb->max;
 531
 532         if (unlikely(count > br->hash_elasticity && count)) {
 533                 if (net_ratelimit())
 534                         br_info(br, "Multicast hash table "
 535                                 "chain limit reached: %s\n",
 536                                 port ? port->dev->name : br->dev->name);
 537
 538                 elasticity = br->hash_elasticity;
 539         }
 540
 541         if (mdb->size >= max) {
 542                 max *= 2;
 543                 if (unlikely(max >= br->hash_max)) {
 544                         br_warn(br, "Multicast hash table maximum "
 545                                 "reached, disabling snooping: %s, %d\n",
 546                                 port ? port->dev->name : br->dev->name, max);
 547                         err = -E2BIG;
 548 disable:
 549                         br->multicast_disabled = 1;
 550                         goto err;
 551                 }
 552         }
 553
 554         if (max > mdb->max || elasticity) {
 555                 if (mdb->old) {
 556                         if (net_ratelimit())
 557                                 br_info(br, "Multicast hash table "
 558                                         "on fire: %s\n",
 559                                         port ? port->dev->name : br->dev->name);
 560                         err = -EEXIST;
 561                         goto err;
 562                 }
 563
 564                 err = br_mdb_rehash(&br->mdb, max, elasticity);
 565                 if (err) {
 566                         br_warn(br, "Cannot rehash multicast "
 567                                 "hash table, disabling snooping: %s, %d, %d\n",
 568                                 port ? port->dev->name : br->dev->name,
 569                                 mdb->size, err);
 570                         goto disable;
 571                 }
 572
 573                 err = -EAGAIN;
 574                 goto err;
 575         }
 576
 577         return NULL;
 578
 579 err:
 580         mp = ERR_PTR(err);
 581         return mp;
 582 }
 583
 584 static struct net_bridge_mdb_entry *br_multicast_new_group(
 585         struct net_bridge *br, struct net_bridge_port *port,
 586         struct br_ip *group)
 587 {
 588         struct net_bridge_mdb_htable *mdb;
 589         struct net_bridge_mdb_entry *mp;
 590         int hash;
 591         int err;
 592
 593         mdb = rcu_dereference_protected(br->mdb, 1);
 594         if (!mdb) {
 595                 err = br_mdb_rehash(&br->mdb, BR_HASH_SIZE, 0);
 596                 if (err)
 597                         return ERR_PTR(err);
 598                 goto rehash;
 599         }
 600
 601         hash = br_ip_hash(mdb, group);
 602         mp = br_multicast_get_group(br, port, group, hash);
 603         switch (PTR_ERR(mp)) {
 604         case 0:
 605                 break;
 606
 607         case -EAGAIN:
 608 rehash:
 609                 mdb = rcu_dereference_protected(br->mdb, 1);
 610                 hash = br_ip_hash(mdb, group);
 611                 break;
 612
 613         default:
 614                 goto out;
 615         }
 616
 617         mp = kzalloc(sizeof(*mp), GFP_ATOMIC);
 618         if (unlikely(!mp))
 619                 return ERR_PTR(-ENOMEM);
 620
 621         mp->br = br;
 622         mp->addr = *group;
 623         setup_timer(&mp->timer, br_multicast_group_expired,
 624                     (unsigned long)mp);
 625
 626         hlist_add_head_rcu(&mp->hlist[mdb->ver], &mdb->mhash[hash]);
 627         mdb->size++;
 628
 629 out:
 630         return mp;
 631 }
 632
 633 static int br_multicast_add_group(struct net_bridge *br,
 634                                   struct net_bridge_port *port,
 635                                   struct br_ip *group)
 636 {
 637         struct net_bridge_mdb_entry *mp;
 638         struct net_bridge_port_group *p;
 639         struct net_bridge_port_group __rcu **pp;
 640         unsigned long now = jiffies;
 641         int err;
 642
 643         spin_lock(&br->multicast_lock);
 644         if (!netif_running(br->dev) ||
 645             (port && port->state == BR_STATE_DISABLED))
 646                 goto out;
 647
 648         mp = br_multicast_new_group(br, port, group);
 649         err = PTR_ERR(mp);
 650         if (IS_ERR(mp))
 651                 goto err;
 652
 653         if (!port) {
 654                 mp->mglist = true;
 655                 mod_timer(&mp->timer, now + br->multicast_membership_interval);
 656                 goto out;
 657         }
 658
 659         for (pp = &mp->ports;
 660              (p = mlock_dereference(*pp, br)) != NULL;
 661              pp = &p->next) {
 662                 if (p->port == port)
 663                         goto found;
 664                 if ((unsigned long)p->port < (unsigned long)port)
 665                         break;
 666         }
 667
 668         p = kzalloc(sizeof(*p), GFP_ATOMIC);
 669         err = -ENOMEM;
 670         if (unlikely(!p))
 671                 goto err;
 672
 673         p->addr = *group;
 674         p->port = port;
 675         p->next = *pp;
 676         hlist_add_head(&p->mglist, &port->mglist);
 677         setup_timer(&p->timer, br_multicast_port_group_expired,
 678                     (unsigned long)p);
 679
 680         rcu_assign_pointer(*pp, p);
 681
 682 found:
 683         mod_timer(&p->timer, now + br->multicast_membership_interval);
 684 out:
 685         err = 0;
 686
 687 err:
 688         spin_unlock(&br->multicast_lock);
 689         return err;
 690 }
 691
 692 static int br_ip4_multicast_add_group(struct net_bridge *br,
 693                                       struct net_bridge_port *port,
 694                                       __be32 group)
 695 {
 696         struct br_ip br_group;
 697
 698         if (ipv4_is_local_multicast(group))
 699                 return 0;
 700
 701         br_group.u.ip4 = group;
 702         br_group.proto = htons(ETH_P_IP);
 703
 704         return br_multicast_add_group(br, port, &br_group);
 705 }
 706
 707 #if IS_ENABLED(CONFIG_IPV6)
 708 static int br_ip6_multicast_add_group(struct net_bridge *br,
 709                                       struct net_bridge_port *port,
 710                                       const struct in6_addr *group)
 711 {
 712         struct br_ip br_group;
 713
 714         if (!ipv6_is_transient_multicast(group))
 715                 return 0;
 716
 717         br_group.u.ip6 = *group;
 718         br_group.proto = htons(ETH_P_IPV6);
 719
 720         return br_multicast_add_group(br, port, &br_group);
 721 }
 722 #endif
 723
 724 static void br_multicast_router_expired(unsigned long data)
 725 {
 726         struct net_bridge_port *port = (void *)data;
 727         struct net_bridge *br = port->br;
 728
 729         spin_lock(&br->multicast_lock);
 730         if (port->multicast_router != 1 ||
 731             timer_pending(&port->multicast_router_timer) ||
 732             hlist_unhashed(&port->rlist))
 733                 goto out;
 734
 735         hlist_del_init_rcu(&port->rlist);
 736
 737 out:
 738         spin_unlock(&br->multicast_lock);
 739 }
 740
 741 static void br_multicast_local_router_expired(unsigned long data)
 742 {
 743 }
 744
 745 static void br_multicast_querier_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 (!netif_running(br->dev) || br->multicast_disabled)
 752                 goto out;
 753
 754         br_multicast_start_querier(br);
 755
 756 out:
 757         spin_unlock(&br->multicast_lock);
 758 }
 759
 760 static void __br_multicast_send_query(struct net_bridge *br,
 761                                       struct net_bridge_port *port,
 762                                       struct br_ip *ip)
 763 {
 764         struct sk_buff *skb;
 765
 766         skb = br_multicast_alloc_query(br, ip);
 767         if (!skb)
 768                 return;
 769
 770         if (port) {
 771                 __skb_push(skb, sizeof(struct ethhdr));
 772                 skb->dev = port->dev;
 773                 NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
 774                         dev_queue_xmit);
 775         } else
 776                 netif_rx(skb);
 777 }
 778
 779 static void br_multicast_send_query(struct net_bridge *br,
 780                                     struct net_bridge_port *port, u32 sent)
 781 {
 782         unsigned long time;
 783         struct br_ip br_group;
 784
 785         if (!netif_running(br->dev) || br->multicast_disabled ||
 786             !br->multicast_querier ||
 787             timer_pending(&br->multicast_querier_timer))
 788                 return;
 789
 790         memset(&br_group.u, 0, sizeof(br_group.u));
 791
 792         br_group.proto = htons(ETH_P_IP);
 793         __br_multicast_send_query(br, port, &br_group);
 794
 795 #if IS_ENABLED(CONFIG_IPV6)
 796         br_group.proto = htons(ETH_P_IPV6);
 797         __br_multicast_send_query(br, port, &br_group);
 798 #endif
 799
 800         time = jiffies;
 801         time += sent < br->multicast_startup_query_count ?
 802                 br->multicast_startup_query_interval :
 803                 br->multicast_query_interval;
 804         mod_timer(port ? &port->multicast_query_timer :
 805                          &br->multicast_query_timer, time);
 806 }
 807
 808 static void br_multicast_port_query_expired(unsigned long data)
 809 {
 810         struct net_bridge_port *port = (void *)data;
 811         struct net_bridge *br = port->br;
 812
 813         spin_lock(&br->multicast_lock);
 814         if (port->state == BR_STATE_DISABLED ||
 815             port->state == BR_STATE_BLOCKING)
 816                 goto out;
 817
 818         if (port->multicast_startup_queries_sent <
 819             br->multicast_startup_query_count)
 820                 port->multicast_startup_queries_sent++;
 821
 822         br_multicast_send_query(port->br, port,
 823                                 port->multicast_startup_queries_sent);
 824
 825 out:
 826         spin_unlock(&br->multicast_lock);
 827 }
 828
 829 void br_multicast_add_port(struct net_bridge_port *port)
 830 {
 831         port->multicast_router = 1;
 832
 833         setup_timer(&port->multicast_router_timer, br_multicast_router_expired,
 834                     (unsigned long)port);
 835         setup_timer(&port->multicast_query_timer,
 836                     br_multicast_port_query_expired, (unsigned long)port);
 837 }
 838
 839 void br_multicast_del_port(struct net_bridge_port *port)
 840 {
 841         del_timer_sync(&port->multicast_router_timer);
 842 }
 843
 844 static void __br_multicast_enable_port(struct net_bridge_port *port)
 845 {
 846         port->multicast_startup_queries_sent = 0;
 847
 848         if (try_to_del_timer_sync(&port->multicast_query_timer) >= 0 ||
 849             del_timer(&port->multicast_query_timer))
 850                 mod_timer(&port->multicast_query_timer, jiffies);
 851 }
 852
 853 void br_multicast_enable_port(struct net_bridge_port *port)
 854 {
 855         struct net_bridge *br = port->br;
 856
 857         spin_lock(&br->multicast_lock);
 858         if (br->multicast_disabled || !netif_running(br->dev))
 859                 goto out;
 860
 861         __br_multicast_enable_port(port);
 862
 863 out:
 864         spin_unlock(&br->multicast_lock);
 865 }
 866
 867 void br_multicast_disable_port(struct net_bridge_port *port)
 868 {
 869         struct net_bridge *br = port->br;
 870         struct net_bridge_port_group *pg;
 871         struct hlist_node *p, *n;
 872
 873         spin_lock(&br->multicast_lock);
 874         hlist_for_each_entry_safe(pg, p, n, &port->mglist, mglist)
 875                 br_multicast_del_pg(br, pg);
 876
 877         if (!hlist_unhashed(&port->rlist))
 878                 hlist_del_init_rcu(&port->rlist);
 879         del_timer(&port->multicast_router_timer);
 880         del_timer(&port->multicast_query_timer);
 881         spin_unlock(&br->multicast_lock);
 882 }
 883
 884 static int br_ip4_multicast_igmp3_report(struct net_bridge *br,
 885                                          struct net_bridge_port *port,
 886                                          struct sk_buff *skb)
 887 {
 888         struct igmpv3_report *ih;
 889         struct igmpv3_grec *grec;
 890         int i;
 891         int len;
 892         int num;
 893         int type;
 894         int err = 0;
 895         __be32 group;
 896
 897         if (!pskb_may_pull(skb, sizeof(*ih)))
 898                 return -EINVAL;
 899
 900         ih = igmpv3_report_hdr(skb);
 901         num = ntohs(ih->ngrec);
 902         len = sizeof(*ih);
 903
 904         for (i = 0; i < num; i++) {
 905                 len += sizeof(*grec);
 906                 if (!pskb_may_pull(skb, len))
 907                         return -EINVAL;
 908
 909                 grec = (void *)(skb->data + len - sizeof(*grec));
 910                 group = grec->grec_mca;
 911                 type = grec->grec_type;
 912
 913                 len += ntohs(grec->grec_nsrcs) * 4;
 914                 if (!pskb_may_pull(skb, len))
 915                         return -EINVAL;
 916
 917                 /* We treat this as an IGMPv2 report for now. */
 918                 switch (type) {
 919                 case IGMPV3_MODE_IS_INCLUDE:
 920                 case IGMPV3_MODE_IS_EXCLUDE:
 921                 case IGMPV3_CHANGE_TO_INCLUDE:
 922                 case IGMPV3_CHANGE_TO_EXCLUDE:
 923                 case IGMPV3_ALLOW_NEW_SOURCES:
 924                 case IGMPV3_BLOCK_OLD_SOURCES:
 925                         break;
 926
 927                 default:
 928                         continue;
 929                 }
 930
 931                 err = br_ip4_multicast_add_group(br, port, group);
 932                 if (err)
 933                         break;
 934         }
 935
 936         return err;
 937 }
 938
 939 #if IS_ENABLED(CONFIG_IPV6)
 940 static int br_ip6_multicast_mld2_report(struct net_bridge *br,
 941                                         struct net_bridge_port *port,
 942                                         struct sk_buff *skb)
 943 {
 944         struct icmp6hdr *icmp6h;
 945         struct mld2_grec *grec;
 946         int i;
 947         int len;
 948         int num;
 949         int err = 0;
 950
 951         if (!pskb_may_pull(skb, sizeof(*icmp6h)))
 952                 return -EINVAL;
 953
 954         icmp6h = icmp6_hdr(skb);
 955         num = ntohs(icmp6h->icmp6_dataun.un_data16[1]);
 956         len = sizeof(*icmp6h);
 957
 958         for (i = 0; i < num; i++) {
 959                 __be16 *nsrcs, _nsrcs;
 960
 961                 nsrcs = skb_header_pointer(skb,
 962                                            len + offsetof(struct mld2_grec,
 963                                                           grec_nsrcs),
 964                                            sizeof(_nsrcs), &_nsrcs);
 965                 if (!nsrcs)
 966                         return -EINVAL;
 967
 968                 if (!pskb_may_pull(skb,
 969                                    len + sizeof(*grec) +
 970                                    sizeof(struct in6_addr) * ntohs(*nsrcs)))
 971                         return -EINVAL;
 972
 973                 grec = (struct mld2_grec *)(skb->data + len);
 974                 len += sizeof(*grec) +
 975                        sizeof(struct in6_addr) * ntohs(*nsrcs);
 976
 977                 /* We treat these as MLDv1 reports for now. */
 978                 switch (grec->grec_type) {
 979                 case MLD2_MODE_IS_INCLUDE:
 980                 case MLD2_MODE_IS_EXCLUDE:
 981                 case MLD2_CHANGE_TO_INCLUDE:
 982                 case MLD2_CHANGE_TO_EXCLUDE:
 983                 case MLD2_ALLOW_NEW_SOURCES:
 984                 case MLD2_BLOCK_OLD_SOURCES:
 985                         break;
 986
 987                 default:
 988                         continue;
 989                 }
 990
 991                 err = br_ip6_multicast_add_group(br, port, &grec->grec_mca);
 992                 if (!err)
 993                         break;
 994         }
 995
 996         return err;
 997 }
 998 #endif
 999
1000 /*
1001  * Add port to rotuer_list
1002  *  list is maintained ordered by pointer value
1003  *  and locked by br->multicast_lock and RCU
1004  */
1005 static void br_multicast_add_router(struct net_bridge *br,
1006                                     struct net_bridge_port *port)
1007 {
1008         struct net_bridge_port *p;
1009         struct hlist_node *n, *slot = NULL;
1010
1011         hlist_for_each_entry(p, n, &br->router_list, rlist) {
1012                 if ((unsigned long) port >= (unsigned long) p)
1013                         break;
1014                 slot = n;
1015         }
1016
1017         if (slot)
1018                 hlist_add_after_rcu(slot, &port->rlist);
1019         else
1020                 hlist_add_head_rcu(&port->rlist, &br->router_list);
1021 }
1022
1023 static void br_multicast_mark_router(struct net_bridge *br,
1024                                      struct net_bridge_port *port)
1025 {
1026         unsigned long now = jiffies;
1027
1028         if (!port) {
1029                 if (br->multicast_router == 1)
1030                         mod_timer(&br->multicast_router_timer,
1031                                   now + br->multicast_querier_interval);
1032                 return;
1033         }
1034
1035         if (port->multicast_router != 1)
1036                 return;
1037
1038         if (!hlist_unhashed(&port->rlist))
1039                 goto timer;
1040
1041         br_multicast_add_router(br, port);
1042
1043 timer:
1044         mod_timer(&port->multicast_router_timer,
1045                   now + br->multicast_querier_interval);
1046 }
1047
1048 static void br_multicast_query_received(struct net_bridge *br,
1049                                         struct net_bridge_port *port,
1050                                         int saddr)
1051 {
1052         if (saddr)
1053                 mod_timer(&br->multicast_querier_timer,
1054                           jiffies + br->multicast_querier_interval);
1055         else if (timer_pending(&br->multicast_querier_timer))
1056                 return;
1057
1058         br_multicast_mark_router(br, port);
1059 }
1060
1061 static int br_ip4_multicast_query(struct net_bridge *br,
1062                                   struct net_bridge_port *port,
1063                                   struct sk_buff *skb)
1064 {
1065         const struct iphdr *iph = ip_hdr(skb);
1066         struct igmphdr *ih = igmp_hdr(skb);
1067         struct net_bridge_mdb_entry *mp;
1068         struct igmpv3_query *ih3;
1069         struct net_bridge_port_group *p;
1070         struct net_bridge_port_group __rcu **pp;
1071         unsigned long max_delay;
1072         unsigned long now = jiffies;
1073         __be32 group;
1074         int err = 0;
1075
1076         spin_lock(&br->multicast_lock);
1077         if (!netif_running(br->dev) ||
1078             (port && port->state == BR_STATE_DISABLED))
1079                 goto out;
1080
1081         br_multicast_query_received(br, port, !!iph->saddr);
1082
1083         group = ih->group;
1084
1085         if (skb->len == sizeof(*ih)) {
1086                 max_delay = ih->code * (HZ / IGMP_TIMER_SCALE);
1087
1088                 if (!max_delay) {
1089                         max_delay = 10 * HZ;
1090                         group = 0;
1091                 }
1092         } else {
1093                 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query))) {
1094                         err = -EINVAL;
1095                         goto out;
1096                 }
1097
1098                 ih3 = igmpv3_query_hdr(skb);
1099                 if (ih3->nsrcs)
1100                         goto out;
1101
1102                 max_delay = ih3->code ?
1103                             IGMPV3_MRC(ih3->code) * (HZ / IGMP_TIMER_SCALE) : 1;
1104         }
1105
1106         if (!group)
1107                 goto out;
1108
1109         mp = br_mdb_ip4_get(mlock_dereference(br->mdb, br), group);
1110         if (!mp)
1111                 goto out;
1112
1113         max_delay *= br->multicast_last_member_count;
1114
1115         if (mp->mglist &&
1116             (timer_pending(&mp->timer) ?
1117              time_after(mp->timer.expires, now + max_delay) :
1118              try_to_del_timer_sync(&mp->timer) >= 0))
1119                 mod_timer(&mp->timer, now + max_delay);
1120
1121         for (pp = &mp->ports;
1122              (p = mlock_dereference(*pp, br)) != NULL;
1123              pp = &p->next) {
1124                 if (timer_pending(&p->timer) ?
1125                     time_after(p->timer.expires, now + max_delay) :
1126                     try_to_del_timer_sync(&p->timer) >= 0)
1127                         mod_timer(&p->timer, now + max_delay);
1128         }
1129
1130 out:
1131         spin_unlock(&br->multicast_lock);
1132         return err;
1133 }
1134
1135 #if IS_ENABLED(CONFIG_IPV6)
1136 static int br_ip6_multicast_query(struct net_bridge *br,
1137                                   struct net_bridge_port *port,
1138                                   struct sk_buff *skb)
1139 {
1140         const struct ipv6hdr *ip6h = ipv6_hdr(skb);
1141         struct mld_msg *mld = (struct mld_msg *) icmp6_hdr(skb);
1142         struct net_bridge_mdb_entry *mp;
1143         struct mld2_query *mld2q;
1144         struct net_bridge_port_group *p;
1145         struct net_bridge_port_group __rcu **pp;
1146         unsigned long max_delay;
1147         unsigned long now = jiffies;
1148         const struct in6_addr *group = NULL;
1149         int err = 0;
1150
1151         spin_lock(&br->multicast_lock);
1152         if (!netif_running(br->dev) ||
1153             (port && port->state == BR_STATE_DISABLED))
1154                 goto out;
1155
1156         br_multicast_query_received(br, port, !ipv6_addr_any(&ip6h->saddr));
1157
1158         if (skb->len == sizeof(*mld)) {
1159                 if (!pskb_may_pull(skb, sizeof(*mld))) {
1160                         err = -EINVAL;
1161                         goto out;
1162                 }
1163                 mld = (struct mld_msg *) icmp6_hdr(skb);
1164                 max_delay = msecs_to_jiffies(htons(mld->mld_maxdelay));
1165                 if (max_delay)
1166                         group = &mld->mld_mca;
1167         } else if (skb->len >= sizeof(*mld2q)) {
1168                 if (!pskb_may_pull(skb, sizeof(*mld2q))) {
1169                         err = -EINVAL;
1170                         goto out;
1171                 }
1172                 mld2q = (struct mld2_query *)icmp6_hdr(skb);
1173                 if (!mld2q->mld2q_nsrcs)
1174                         group = &mld2q->mld2q_mca;
1175                 max_delay = mld2q->mld2q_mrc ? MLDV2_MRC(mld2q->mld2q_mrc) : 1;
1176         }
1177
1178         if (!group)
1179                 goto out;
1180
1181         mp = br_mdb_ip6_get(mlock_dereference(br->mdb, br), group);
1182         if (!mp)
1183                 goto out;
1184
1185         max_delay *= br->multicast_last_member_count;
1186         if (mp->mglist &&
1187             (timer_pending(&mp->timer) ?
1188              time_after(mp->timer.expires, now + max_delay) :
1189              try_to_del_timer_sync(&mp->timer) >= 0))
1190                 mod_timer(&mp->timer, now + max_delay);
1191
1192         for (pp = &mp->ports;
1193              (p = mlock_dereference(*pp, br)) != NULL;
1194              pp = &p->next) {
1195                 if (timer_pending(&p->timer) ?
1196                     time_after(p->timer.expires, now + max_delay) :
1197                     try_to_del_timer_sync(&p->timer) >= 0)
1198                         mod_timer(&p->timer, now + max_delay);
1199         }
1200
1201 out:
1202         spin_unlock(&br->multicast_lock);
1203         return err;
1204 }
1205 #endif
1206
1207 static void br_multicast_leave_group(struct net_bridge *br,
1208                                      struct net_bridge_port *port,
1209                                      struct br_ip *group)
1210 {
1211         struct net_bridge_mdb_htable *mdb;
1212         struct net_bridge_mdb_entry *mp;
1213         struct net_bridge_port_group *p;
1214         unsigned long now;
1215         unsigned long time;
1216
1217         spin_lock(&br->multicast_lock);
1218         if (!netif_running(br->dev) ||
1219             (port && port->state == BR_STATE_DISABLED) ||
1220             timer_pending(&br->multicast_querier_timer))
1221                 goto out;
1222
1223         mdb = mlock_dereference(br->mdb, br);
1224         mp = br_mdb_ip_get(mdb, group);
1225         if (!mp)
1226                 goto out;
1227
1228         now = jiffies;
1229         time = now + br->multicast_last_member_count *
1230                      br->multicast_last_member_interval;
1231
1232         if (!port) {
1233                 if (mp->mglist &&
1234                     (timer_pending(&mp->timer) ?
1235                      time_after(mp->timer.expires, time) :
1236                      try_to_del_timer_sync(&mp->timer) >= 0)) {
1237                         mod_timer(&mp->timer, time);
1238                 }
1239
1240                 goto out;
1241         }
1242
1243         for (p = mlock_dereference(mp->ports, br);
1244              p != NULL;
1245              p = mlock_dereference(p->next, br)) {
1246                 if (p->port != port)
1247                         continue;
1248
1249                 if (!hlist_unhashed(&p->mglist) &&
1250                     (timer_pending(&p->timer) ?
1251                      time_after(p->timer.expires, time) :
1252                      try_to_del_timer_sync(&p->timer) >= 0)) {
1253                         mod_timer(&p->timer, time);
1254                 }
1255
1256                 break;
1257         }
1258
1259 out:
1260         spin_unlock(&br->multicast_lock);
1261 }
1262
1263 static void br_ip4_multicast_leave_group(struct net_bridge *br,
1264                                          struct net_bridge_port *port,
1265                                          __be32 group)
1266 {
1267         struct br_ip br_group;
1268
1269         if (ipv4_is_local_multicast(group))
1270                 return;
1271
1272         br_group.u.ip4 = group;
1273         br_group.proto = htons(ETH_P_IP);
1274
1275         br_multicast_leave_group(br, port, &br_group);
1276 }
1277
1278 #if IS_ENABLED(CONFIG_IPV6)
1279 static void br_ip6_multicast_leave_group(struct net_bridge *br,
1280                                          struct net_bridge_port *port,
1281                                          const struct in6_addr *group)
1282 {
1283         struct br_ip br_group;
1284
1285         if (!ipv6_is_transient_multicast(group))
1286                 return;
1287
1288         br_group.u.ip6 = *group;
1289         br_group.proto = htons(ETH_P_IPV6);
1290
1291         br_multicast_leave_group(br, port, &br_group);
1292 }
1293 #endif
1294
1295 static int br_multicast_ipv4_rcv(struct net_bridge *br,
1296                                  struct net_bridge_port *port,
1297                                  struct sk_buff *skb)
1298 {
1299         struct sk_buff *skb2 = skb;
1300         const struct iphdr *iph;
1301         struct igmphdr *ih;
1302         unsigned int len;
1303         unsigned int offset;
1304         int err;
1305
1306         /* We treat OOM as packet loss for now. */
1307         if (!pskb_may_pull(skb, sizeof(*iph)))
1308                 return -EINVAL;
1309
1310         iph = ip_hdr(skb);
1311
1312         if (iph->ihl < 5 || iph->version != 4)
1313                 return -EINVAL;
1314
1315         if (!pskb_may_pull(skb, ip_hdrlen(skb)))
1316                 return -EINVAL;
1317
1318         iph = ip_hdr(skb);
1319
1320         if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
1321                 return -EINVAL;
1322
1323         if (iph->protocol != IPPROTO_IGMP) {
1324                 if ((iph->daddr & IGMP_LOCAL_GROUP_MASK) != IGMP_LOCAL_GROUP)
1325                         BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1326                 return 0;
1327         }
1328
1329         len = ntohs(iph->tot_len);
1330         if (skb->len < len || len < ip_hdrlen(skb))
1331                 return -EINVAL;
1332
1333         if (skb->len > len) {
1334                 skb2 = skb_clone(skb, GFP_ATOMIC);
1335                 if (!skb2)
1336                         return -ENOMEM;
1337
1338                 err = pskb_trim_rcsum(skb2, len);
1339                 if (err)
1340                         goto err_out;
1341         }
1342
1343         len -= ip_hdrlen(skb2);
1344         offset = skb_network_offset(skb2) + ip_hdrlen(skb2);
1345         __skb_pull(skb2, offset);
1346         skb_reset_transport_header(skb2);
1347
1348         err = -EINVAL;
1349         if (!pskb_may_pull(skb2, sizeof(*ih)))
1350                 goto out;
1351
1352         switch (skb2->ip_summed) {
1353         case CHECKSUM_COMPLETE:
1354                 if (!csum_fold(skb2->csum))
1355                         break;
1356                 /* fall through */
1357         case CHECKSUM_NONE:
1358                 skb2->csum = 0;
1359                 if (skb_checksum_complete(skb2))
1360                         goto out;
1361         }
1362
1363         err = 0;
1364
1365         BR_INPUT_SKB_CB(skb)->igmp = 1;
1366         ih = igmp_hdr(skb2);
1367
1368         switch (ih->type) {
1369         case IGMP_HOST_MEMBERSHIP_REPORT:
1370         case IGMPV2_HOST_MEMBERSHIP_REPORT:
1371                 BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1372                 err = br_ip4_multicast_add_group(br, port, ih->group);
1373                 break;
1374         case IGMPV3_HOST_MEMBERSHIP_REPORT:
1375                 err = br_ip4_multicast_igmp3_report(br, port, skb2);
1376                 break;
1377         case IGMP_HOST_MEMBERSHIP_QUERY:
1378                 err = br_ip4_multicast_query(br, port, skb2);
1379                 break;
1380         case IGMP_HOST_LEAVE_MESSAGE:
1381                 br_ip4_multicast_leave_group(br, port, ih->group);
1382                 break;
1383         }
1384
1385 out:
1386         __skb_push(skb2, offset);
1387 err_out:
1388         if (skb2 != skb)
1389                 kfree_skb(skb2);
1390         return err;
1391 }
1392
1393 #if IS_ENABLED(CONFIG_IPV6)
1394 static int br_multicast_ipv6_rcv(struct net_bridge *br,
1395                                  struct net_bridge_port *port,
1396                                  struct sk_buff *skb)
1397 {
1398         struct sk_buff *skb2;
1399         const struct ipv6hdr *ip6h;
1400         u8 icmp6_type;
1401         u8 nexthdr;
1402         __be16 frag_off;
1403         unsigned int len;
1404         int offset;
1405         int err;
1406
1407         if (!pskb_may_pull(skb, sizeof(*ip6h)))
1408                 return -EINVAL;
1409
1410         ip6h = ipv6_hdr(skb);
1411
1412         /*
1413          * We're interested in MLD messages only.
1414          *  - Version is 6
1415          *  - MLD has always Router Alert hop-by-hop option
1416          *  - But we do not support jumbrograms.
1417          */
1418         if (ip6h->version != 6 ||
1419             ip6h->nexthdr != IPPROTO_HOPOPTS ||
1420             ip6h->payload_len == 0)
1421                 return 0;
1422
1423         len = ntohs(ip6h->payload_len) + sizeof(*ip6h);
1424         if (skb->len < len)
1425                 return -EINVAL;
1426
1427         nexthdr = ip6h->nexthdr;
1428         offset = ipv6_skip_exthdr(skb, sizeof(*ip6h), &nexthdr, &frag_off);
1429
1430         if (offset < 0 || nexthdr != IPPROTO_ICMPV6)
1431                 return 0;
1432
1433         /* Okay, we found ICMPv6 header */
1434         skb2 = skb_clone(skb, GFP_ATOMIC);
1435         if (!skb2)
1436                 return -ENOMEM;
1437
1438         err = -EINVAL;
1439         if (!pskb_may_pull(skb2, offset + sizeof(struct icmp6hdr)))
1440                 goto out;
1441
1442         len -= offset - skb_network_offset(skb2);
1443
1444         __skb_pull(skb2, offset);
1445         skb_reset_transport_header(skb2);
1446         skb_postpull_rcsum(skb2, skb_network_header(skb2),
1447                            skb_network_header_len(skb2));
1448
1449         icmp6_type = icmp6_hdr(skb2)->icmp6_type;
1450
1451         switch (icmp6_type) {
1452         case ICMPV6_MGM_QUERY:
1453         case ICMPV6_MGM_REPORT:
1454         case ICMPV6_MGM_REDUCTION:
1455         case ICMPV6_MLD2_REPORT:
1456                 break;
1457         default:
1458                 err = 0;
1459                 goto out;
1460         }
1461
1462         /* Okay, we found MLD message. Check further. */
1463         if (skb2->len > len) {
1464                 err = pskb_trim_rcsum(skb2, len);
1465                 if (err)
1466                         goto out;
1467                 err = -EINVAL;
1468         }
1469
1470         ip6h = ipv6_hdr(skb2);
1471
1472         switch (skb2->ip_summed) {
1473         case CHECKSUM_COMPLETE:
1474                 if (!csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, skb2->len,
1475                                         IPPROTO_ICMPV6, skb2->csum))
1476                         break;
1477                 /*FALLTHROUGH*/
1478         case CHECKSUM_NONE:
1479                 skb2->csum = ~csum_unfold(csum_ipv6_magic(&ip6h->saddr,
1480                                                         &ip6h->daddr,
1481                                                         skb2->len,
1482                                                         IPPROTO_ICMPV6, 0));
1483                 if (__skb_checksum_complete(skb2))
1484                         goto out;
1485         }
1486
1487         err = 0;
1488
1489         BR_INPUT_SKB_CB(skb)->igmp = 1;
1490
1491         switch (icmp6_type) {
1492         case ICMPV6_MGM_REPORT:
1493             {
1494                 struct mld_msg *mld;
1495                 if (!pskb_may_pull(skb2, sizeof(*mld))) {
1496                         err = -EINVAL;
1497                         goto out;
1498                 }
1499                 mld = (struct mld_msg *)skb_transport_header(skb2);
1500                 BR_INPUT_SKB_CB(skb)->mrouters_only = 1;
1501                 err = br_ip6_multicast_add_group(br, port, &mld->mld_mca);
1502                 break;
1503             }
1504         case ICMPV6_MLD2_REPORT:
1505                 err = br_ip6_multicast_mld2_report(br, port, skb2);
1506                 break;
1507         case ICMPV6_MGM_QUERY:
1508                 err = br_ip6_multicast_query(br, port, skb2);
1509                 break;
1510         case ICMPV6_MGM_REDUCTION:
1511             {
1512                 struct mld_msg *mld;
1513                 if (!pskb_may_pull(skb2, sizeof(*mld))) {
1514                         err = -EINVAL;
1515                         goto out;
1516                 }
1517                 mld = (struct mld_msg *)skb_transport_header(skb2);
1518                 br_ip6_multicast_leave_group(br, port, &mld->mld_mca);
1519             }
1520         }
1521
1522 out:
1523         kfree_skb(skb2);
1524         return err;
1525 }
1526 #endif
1527
1528 int br_multicast_rcv(struct net_bridge *br, struct net_bridge_port *port,
1529                      struct sk_buff *skb)
1530 {
1531         BR_INPUT_SKB_CB(skb)->igmp = 0;
1532         BR_INPUT_SKB_CB(skb)->mrouters_only = 0;
1533
1534         if (br->multicast_disabled)
1535                 return 0;
1536
1537         switch (skb->protocol) {
1538         case htons(ETH_P_IP):
1539                 return br_multicast_ipv4_rcv(br, port, skb);
1540 #if IS_ENABLED(CONFIG_IPV6)
1541         case htons(ETH_P_IPV6):
1542                 return br_multicast_ipv6_rcv(br, port, skb);
1543 #endif
1544         }
1545
1546         return 0;
1547 }
1548
1549 static void br_multicast_query_expired(unsigned long data)
1550 {
1551         struct net_bridge *br = (void *)data;
1552
1553         spin_lock(&br->multicast_lock);
1554         if (br->multicast_startup_queries_sent <
1555             br->multicast_startup_query_count)
1556                 br->multicast_startup_queries_sent++;
1557
1558         br_multicast_send_query(br, NULL, br->multicast_startup_queries_sent);
1559
1560         spin_unlock(&br->multicast_lock);
1561 }
1562
1563 void br_multicast_init(struct net_bridge *br)
1564 {
1565         br->hash_elasticity = 4;
1566         br->hash_max = 512;
1567
1568         br->multicast_router = 1;
1569         br->multicast_querier = 0;
1570         br->multicast_last_member_count = 2;
1571         br->multicast_startup_query_count = 2;
1572
1573         br->multicast_last_member_interval = HZ;
1574         br->multicast_query_response_interval = 10 * HZ;
1575         br->multicast_startup_query_interval = 125 * HZ / 4;
1576         br->multicast_query_interval = 125 * HZ;
1577         br->multicast_querier_interval = 255 * HZ;
1578         br->multicast_membership_interval = 260 * HZ;
1579
1580         spin_lock_init(&br->multicast_lock);
1581         setup_timer(&br->multicast_router_timer,
1582                     br_multicast_local_router_expired, 0);
1583         setup_timer(&br->multicast_querier_timer,
1584                     br_multicast_querier_expired, 0);
1585         setup_timer(&br->multicast_query_timer, br_multicast_query_expired,
1586                     (unsigned long)br);
1587 }
1588
1589 void br_multicast_open(struct net_bridge *br)
1590 {
1591         br->multicast_startup_queries_sent = 0;
1592
1593         if (br->multicast_disabled)
1594                 return;
1595
1596         mod_timer(&br->multicast_query_timer, jiffies);
1597 }
1598
1599 void br_multicast_stop(struct net_bridge *br)
1600 {
1601         struct net_bridge_mdb_htable *mdb;
1602         struct net_bridge_mdb_entry *mp;
1603         struct hlist_node *p, *n;
1604         u32 ver;
1605         int i;
1606
1607         del_timer_sync(&br->multicast_router_timer);
1608         del_timer_sync(&br->multicast_querier_timer);
1609         del_timer_sync(&br->multicast_query_timer);
1610
1611         spin_lock_bh(&br->multicast_lock);
1612         mdb = mlock_dereference(br->mdb, br);
1613         if (!mdb)
1614                 goto out;
1615
1616         br->mdb = NULL;
1617
1618         ver = mdb->ver;
1619         for (i = 0; i < mdb->max; i++) {
1620                 hlist_for_each_entry_safe(mp, p, n, &mdb->mhash[i],
1621                                           hlist[ver]) {
1622                         del_timer(&mp->timer);
1623                         call_rcu_bh(&mp->rcu, br_multicast_free_group);
1624                 }
1625         }
1626
1627         if (mdb->old) {
1628                 spin_unlock_bh(&br->multicast_lock);
1629                 rcu_barrier_bh();
1630                 spin_lock_bh(&br->multicast_lock);
1631                 WARN_ON(mdb->old);
1632         }
1633
1634         mdb->old = mdb;
1635         call_rcu_bh(&mdb->rcu, br_mdb_free);
1636
1637 out:
1638         spin_unlock_bh(&br->multicast_lock);
1639 }
1640
1641 int br_multicast_set_router(struct net_bridge *br, unsigned long val)
1642 {
1643         int err = -ENOENT;
1644
1645         spin_lock_bh(&br->multicast_lock);
1646         if (!netif_running(br->dev))
1647                 goto unlock;
1648
1649         switch (val) {
1650         case 0:
1651         case 2:
1652                 del_timer(&br->multicast_router_timer);
1653                 /* fall through */
1654         case 1:
1655                 br->multicast_router = val;
1656                 err = 0;
1657                 break;
1658
1659         default:
1660                 err = -EINVAL;
1661                 break;
1662         }
1663
1664 unlock:
1665         spin_unlock_bh(&br->multicast_lock);
1666
1667         return err;
1668 }
1669
1670 int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
1671 {
1672         struct net_bridge *br = p->br;
1673         int err = -ENOENT;
1674
1675         spin_lock(&br->multicast_lock);
1676         if (!netif_running(br->dev) || p->state == BR_STATE_DISABLED)
1677                 goto unlock;
1678
1679         switch (val) {
1680         case 0:
1681         case 1:
1682         case 2:
1683                 p->multicast_router = val;
1684                 err = 0;
1685
1686                 if (val < 2 && !hlist_unhashed(&p->rlist))
1687                         hlist_del_init_rcu(&p->rlist);
1688
1689                 if (val == 1)
1690                         break;
1691
1692                 del_timer(&p->multicast_router_timer);
1693
1694                 if (val == 0)
1695                         break;
1696
1697                 br_multicast_add_router(br, p);
1698                 break;
1699
1700         default:
1701                 err = -EINVAL;
1702                 break;
1703         }
1704
1705 unlock:
1706         spin_unlock(&br->multicast_lock);
1707
1708         return err;
1709 }
1710
1711 static void br_multicast_start_querier(struct net_bridge *br)
1712 {
1713         struct net_bridge_port *port;
1714
1715         br_multicast_open(br);
1716
1717         list_for_each_entry(port, &br->port_list, list) {
1718                 if (port->state == BR_STATE_DISABLED ||
1719                     port->state == BR_STATE_BLOCKING)
1720                         continue;
1721
1722                 __br_multicast_enable_port(port);
1723         }
1724 }
1725
1726 int br_multicast_toggle(struct net_bridge *br, unsigned long val)
1727 {
1728         int err = 0;
1729         struct net_bridge_mdb_htable *mdb;
1730
1731         spin_lock_bh(&br->multicast_lock);
1732         if (br->multicast_disabled == !val)
1733                 goto unlock;
1734
1735         br->multicast_disabled = !val;
1736         if (br->multicast_disabled)
1737                 goto unlock;
1738
1739         if (!netif_running(br->dev))
1740                 goto unlock;
1741
1742         mdb = mlock_dereference(br->mdb, br);
1743         if (mdb) {
1744                 if (mdb->old) {
1745                         err = -EEXIST;
1746 rollback:
1747                         br->multicast_disabled = !!val;
1748                         goto unlock;
1749                 }
1750
1751                 err = br_mdb_rehash(&br->mdb, mdb->max,
1752                                     br->hash_elasticity);
1753                 if (err)
1754                         goto rollback;
1755         }
1756
1757         br_multicast_start_querier(br);
1758
1759 unlock:
1760         spin_unlock_bh(&br->multicast_lock);
1761
1762         return err;
1763 }
1764
1765 int br_multicast_set_querier(struct net_bridge *br, unsigned long val)
1766 {
1767         val = !!val;
1768
1769         spin_lock_bh(&br->multicast_lock);
1770         if (br->multicast_querier == val)
1771                 goto unlock;
1772
1773         br->multicast_querier = val;
1774         if (val)
1775                 br_multicast_start_querier(br);
1776
1777 unlock:
1778         spin_unlock_bh(&br->multicast_lock);
1779
1780         return 0;
1781 }
1782
1783 int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val)
1784 {
1785         int err = -ENOENT;
1786         u32 old;
1787         struct net_bridge_mdb_htable *mdb;
1788
1789         spin_lock(&br->multicast_lock);
1790         if (!netif_running(br->dev))
1791                 goto unlock;
1792
1793         err = -EINVAL;
1794         if (!is_power_of_2(val))
1795                 goto unlock;
1796
1797         mdb = mlock_dereference(br->mdb, br);
1798         if (mdb && val < mdb->size)
1799                 goto unlock;
1800
1801         err = 0;
1802
1803         old = br->hash_max;
1804         br->hash_max = val;
1805
1806         if (mdb) {
1807                 if (mdb->old) {
1808                         err = -EEXIST;
1809 rollback:
1810                         br->hash_max = old;
1811                         goto unlock;
1812                 }
1813
1814                 err = br_mdb_rehash(&br->mdb, br->hash_max,
1815                                     br->hash_elasticity);
1816                 if (err)
1817                         goto rollback;
1818         }
1819
1820 unlock:
1821         spin_unlock(&br->multicast_lock);
1822
1823         return err;
1824 }