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 28 #include "br_private.h" 29 30 static inline int br_ip_hash(struct net_bridge_mdb_htable *mdb, __be32 ip) 31 { 32 return jhash_1word(mdb->secret, (u32)ip) & (mdb->max - 1); 33 } 34 35 static struct net_bridge_mdb_entry *__br_mdb_ip_get( 36 struct net_bridge_mdb_htable *mdb, __be32 dst, int hash) 37 { 38 struct net_bridge_mdb_entry *mp; 39 struct hlist_node *p; 40 41 hlist_for_each_entry_rcu(mp, p, &mdb->mhash[hash], hlist[mdb->ver]) { 42 if (dst == mp->addr) 43 return mp; 44 } 45 46 return NULL; 47 } 48 49 static struct net_bridge_mdb_entry *br_mdb_ip_get( 50 struct net_bridge_mdb_htable *mdb, __be32 dst) 51 { 52 if (!mdb) 53 return NULL; 54 55 return __br_mdb_ip_get(mdb, dst, br_ip_hash(mdb, dst)); 56 } 57 58 struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br, 59 struct sk_buff *skb) 60 { 61 if (br->multicast_disabled) 62 return NULL; 63 64 switch (skb->protocol) { 65 case htons(ETH_P_IP): 66 if (BR_INPUT_SKB_CB(skb)->igmp) 67 break; 68 return br_mdb_ip_get(br->mdb, ip_hdr(skb)->daddr); 69 } 70 71 return NULL; 72 } 73 74 static void br_mdb_free(struct rcu_head *head) 75 { 76 struct net_bridge_mdb_htable *mdb = 77 container_of(head, struct net_bridge_mdb_htable, rcu); 78 struct net_bridge_mdb_htable *old = mdb->old; 79 80 mdb->old = NULL; 81 kfree(old->mhash); 82 kfree(old); 83 } 84 85 static int br_mdb_copy(struct net_bridge_mdb_htable *new, 86 struct net_bridge_mdb_htable *old, 87 int elasticity) 88 { 89 struct net_bridge_mdb_entry *mp; 90 struct hlist_node *p; 91 int maxlen; 92 int len; 93 int i; 94 95 for (i = 0; i < old->max; i++) 96 hlist_for_each_entry(mp, p, &old->mhash[i], hlist[old->ver]) 97 hlist_add_head(&mp->hlist[new->ver], 98 &new->mhash[br_ip_hash(new, mp->addr)]); 99 100 if (!elasticity) 101 return 0; 102 103 maxlen = 0; 104 for (i = 0; i < new->max; i++) { 105 len = 0; 106 hlist_for_each_entry(mp, p, &new->mhash[i], hlist[new->ver]) 107 len++; 108 if (len > maxlen) 109 maxlen = len; 110 } 111 112 return maxlen > elasticity ? -EINVAL : 0; 113 } 114 115 static void br_multicast_free_pg(struct rcu_head *head) 116 { 117 struct net_bridge_port_group *p = 118 container_of(head, struct net_bridge_port_group, rcu); 119 120 kfree(p); 121 } 122 123 static void br_multicast_free_group(struct rcu_head *head) 124 { 125 struct net_bridge_mdb_entry *mp = 126 container_of(head, struct net_bridge_mdb_entry, rcu); 127 128 kfree(mp); 129 } 130 131 static void br_multicast_group_expired(unsigned long data) 132 { 133 struct net_bridge_mdb_entry *mp = (void *)data; 134 struct net_bridge *br = mp->br; 135 struct net_bridge_mdb_htable *mdb; 136 137 spin_lock(&br->multicast_lock); 138 if (!netif_running(br->dev) || timer_pending(&mp->timer)) 139 goto out; 140 141 if (!hlist_unhashed(&mp->mglist)) 142 hlist_del_init(&mp->mglist); 143 144 if (mp->ports) 145 goto out; 146 147 mdb = br->mdb; 148 hlist_del_rcu(&mp->hlist[mdb->ver]); 149 mdb->size--; 150 151 del_timer(&mp->query_timer); 152 call_rcu_bh(&mp->rcu, br_multicast_free_group); 153 154 out: 155 spin_unlock(&br->multicast_lock); 156 } 157 158 static void br_multicast_del_pg(struct net_bridge *br, 159 struct net_bridge_port_group *pg) 160 { 161 struct net_bridge_mdb_htable *mdb = br->mdb; 162 struct net_bridge_mdb_entry *mp; 163 struct net_bridge_port_group *p; 164 struct net_bridge_port_group **pp; 165 166 mp = br_mdb_ip_get(mdb, pg->addr); 167 if (WARN_ON(!mp)) 168 return; 169 170 for (pp = &mp->ports; (p = *pp); pp = &p->next) { 171 if (p != pg) 172 continue; 173 174 *pp = p->next; 175 hlist_del_init(&p->mglist); 176 del_timer(&p->timer); 177 del_timer(&p->query_timer); 178 call_rcu_bh(&p->rcu, br_multicast_free_pg); 179 180 if (!mp->ports && hlist_unhashed(&mp->mglist) && 181 netif_running(br->dev)) 182 mod_timer(&mp->timer, jiffies); 183 184 return; 185 } 186 187 WARN_ON(1); 188 } 189 190 static void br_multicast_port_group_expired(unsigned long data) 191 { 192 struct net_bridge_port_group *pg = (void *)data; 193 struct net_bridge *br = pg->port->br; 194 195 spin_lock(&br->multicast_lock); 196 if (!netif_running(br->dev) || timer_pending(&pg->timer) || 197 hlist_unhashed(&pg->mglist)) 198 goto out; 199 200 br_multicast_del_pg(br, pg); 201 202 out: 203 spin_unlock(&br->multicast_lock); 204 } 205 206 static int br_mdb_rehash(struct net_bridge_mdb_htable **mdbp, int max, 207 int elasticity) 208 { 209 struct net_bridge_mdb_htable *old = *mdbp; 210 struct net_bridge_mdb_htable *mdb; 211 int err; 212 213 mdb = kmalloc(sizeof(*mdb), GFP_ATOMIC); 214 if (!mdb) 215 return -ENOMEM; 216 217 mdb->max = max; 218 mdb->old = old; 219 220 mdb->mhash = kzalloc(max * sizeof(*mdb->mhash), GFP_ATOMIC); 221 if (!mdb->mhash) { 222 kfree(mdb); 223 return -ENOMEM; 224 } 225 226 mdb->size = old ? old->size : 0; 227 mdb->ver = old ? old->ver ^ 1 : 0; 228 229 if (!old || elasticity) 230 get_random_bytes(&mdb->secret, sizeof(mdb->secret)); 231 else 232 mdb->secret = old->secret; 233 234 if (!old) 235 goto out; 236 237 err = br_mdb_copy(mdb, old, elasticity); 238 if (err) { 239 kfree(mdb->mhash); 240 kfree(mdb); 241 return err; 242 } 243 244 call_rcu_bh(&mdb->rcu, br_mdb_free); 245 246 out: 247 rcu_assign_pointer(*mdbp, mdb); 248 249 return 0; 250 } 251 252 static struct sk_buff *br_multicast_alloc_query(struct net_bridge *br, 253 __be32 group) 254 { 255 struct sk_buff *skb; 256 struct igmphdr *ih; 257 struct ethhdr *eth; 258 struct iphdr *iph; 259 260 skb = netdev_alloc_skb_ip_align(br->dev, sizeof(*eth) + sizeof(*iph) + 261 sizeof(*ih) + 4); 262 if (!skb) 263 goto out; 264 265 skb->protocol = htons(ETH_P_IP); 266 267 skb_reset_mac_header(skb); 268 eth = eth_hdr(skb); 269 270 memcpy(eth->h_source, br->dev->dev_addr, 6); 271 eth->h_dest[0] = 1; 272 eth->h_dest[1] = 0; 273 eth->h_dest[2] = 0x5e; 274 eth->h_dest[3] = 0; 275 eth->h_dest[4] = 0; 276 eth->h_dest[5] = 1; 277 eth->h_proto = htons(ETH_P_IP); 278 skb_put(skb, sizeof(*eth)); 279 280 skb_set_network_header(skb, skb->len); 281 iph = ip_hdr(skb); 282 283 iph->version = 4; 284 iph->ihl = 6; 285 iph->tos = 0xc0; 286 iph->tot_len = htons(sizeof(*iph) + sizeof(*ih) + 4); 287 iph->id = 0; 288 iph->frag_off = htons(IP_DF); 289 iph->ttl = 1; 290 iph->protocol = IPPROTO_IGMP; 291 iph->saddr = 0; 292 iph->daddr = htonl(INADDR_ALLHOSTS_GROUP); 293 ((u8 *)&iph[1])[0] = IPOPT_RA; 294 ((u8 *)&iph[1])[1] = 4; 295 ((u8 *)&iph[1])[2] = 0; 296 ((u8 *)&iph[1])[3] = 0; 297 ip_send_check(iph); 298 skb_put(skb, 24); 299 300 skb_set_transport_header(skb, skb->len); 301 ih = igmp_hdr(skb); 302 ih->type = IGMP_HOST_MEMBERSHIP_QUERY; 303 ih->code = (group ? br->multicast_last_member_interval : 304 br->multicast_query_response_interval) / 305 (HZ / IGMP_TIMER_SCALE); 306 ih->group = group; 307 ih->csum = 0; 308 ih->csum = ip_compute_csum((void *)ih, sizeof(struct igmphdr)); 309 skb_put(skb, sizeof(*ih)); 310 311 __skb_pull(skb, sizeof(*eth)); 312 313 out: 314 return skb; 315 } 316 317 static void br_multicast_send_group_query(struct net_bridge_mdb_entry *mp) 318 { 319 struct net_bridge *br = mp->br; 320 struct sk_buff *skb; 321 322 skb = br_multicast_alloc_query(br, mp->addr); 323 if (!skb) 324 goto timer; 325 326 netif_rx(skb); 327 328 timer: 329 if (++mp->queries_sent < br->multicast_last_member_count) 330 mod_timer(&mp->query_timer, 331 jiffies + br->multicast_last_member_interval); 332 } 333 334 static void br_multicast_group_query_expired(unsigned long data) 335 { 336 struct net_bridge_mdb_entry *mp = (void *)data; 337 struct net_bridge *br = mp->br; 338 339 spin_lock(&br->multicast_lock); 340 if (!netif_running(br->dev) || hlist_unhashed(&mp->mglist) || 341 mp->queries_sent >= br->multicast_last_member_count) 342 goto out; 343 344 br_multicast_send_group_query(mp); 345 346 out: 347 spin_unlock(&br->multicast_lock); 348 } 349 350 static void br_multicast_send_port_group_query(struct net_bridge_port_group *pg) 351 { 352 struct net_bridge_port *port = pg->port; 353 struct net_bridge *br = port->br; 354 struct sk_buff *skb; 355 356 skb = br_multicast_alloc_query(br, pg->addr); 357 if (!skb) 358 goto timer; 359 360 br_deliver(port, skb); 361 362 timer: 363 if (++pg->queries_sent < br->multicast_last_member_count) 364 mod_timer(&pg->query_timer, 365 jiffies + br->multicast_last_member_interval); 366 } 367 368 static void br_multicast_port_group_query_expired(unsigned long data) 369 { 370 struct net_bridge_port_group *pg = (void *)data; 371 struct net_bridge_port *port = pg->port; 372 struct net_bridge *br = port->br; 373 374 spin_lock(&br->multicast_lock); 375 if (!netif_running(br->dev) || hlist_unhashed(&pg->mglist) || 376 pg->queries_sent >= br->multicast_last_member_count) 377 goto out; 378 379 br_multicast_send_port_group_query(pg); 380 381 out: 382 spin_unlock(&br->multicast_lock); 383 } 384 385 static struct net_bridge_mdb_entry *br_multicast_get_group( 386 struct net_bridge *br, struct net_bridge_port *port, __be32 group, 387 int hash) 388 { 389 struct net_bridge_mdb_htable *mdb = br->mdb; 390 struct net_bridge_mdb_entry *mp; 391 struct hlist_node *p; 392 unsigned count = 0; 393 unsigned max; 394 int elasticity; 395 int err; 396 397 hlist_for_each_entry(mp, p, &mdb->mhash[hash], hlist[mdb->ver]) { 398 count++; 399 if (unlikely(group == mp->addr)) { 400 return mp; 401 } 402 } 403 404 elasticity = 0; 405 max = mdb->max; 406 407 if (unlikely(count > br->hash_elasticity && count)) { 408 if (net_ratelimit()) 409 printk(KERN_INFO "%s: Multicast hash table " 410 "chain limit reached: %s\n", 411 br->dev->name, port ? port->dev->name : 412 br->dev->name); 413 414 elasticity = br->hash_elasticity; 415 } 416 417 if (mdb->size >= max) { 418 max *= 2; 419 if (unlikely(max >= br->hash_max)) { 420 printk(KERN_WARNING "%s: Multicast hash table maximum " 421 "reached, disabling snooping: %s, %d\n", 422 br->dev->name, port ? port->dev->name : 423 br->dev->name, 424 max); 425 err = -E2BIG; 426 disable: 427 br->multicast_disabled = 1; 428 goto err; 429 } 430 } 431 432 if (max > mdb->max || elasticity) { 433 if (mdb->old) { 434 if (net_ratelimit()) 435 printk(KERN_INFO "%s: Multicast hash table " 436 "on fire: %s\n", 437 br->dev->name, port ? port->dev->name : 438 br->dev->name); 439 err = -EEXIST; 440 goto err; 441 } 442 443 err = br_mdb_rehash(&br->mdb, max, elasticity); 444 if (err) { 445 printk(KERN_WARNING "%s: Cannot rehash multicast " 446 "hash table, disabling snooping: " 447 "%s, %d, %d\n", 448 br->dev->name, port ? port->dev->name : 449 br->dev->name, 450 mdb->size, err); 451 goto disable; 452 } 453 454 err = -EAGAIN; 455 goto err; 456 } 457 458 return NULL; 459 460 err: 461 mp = ERR_PTR(err); 462 return mp; 463 } 464 465 static struct net_bridge_mdb_entry *br_multicast_new_group( 466 struct net_bridge *br, struct net_bridge_port *port, __be32 group) 467 { 468 struct net_bridge_mdb_htable *mdb = br->mdb; 469 struct net_bridge_mdb_entry *mp; 470 int hash; 471 472 if (!mdb) { 473 if (br_mdb_rehash(&br->mdb, BR_HASH_SIZE, 0)) 474 return NULL; 475 goto rehash; 476 } 477 478 hash = br_ip_hash(mdb, group); 479 mp = br_multicast_get_group(br, port, group, hash); 480 switch (PTR_ERR(mp)) { 481 case 0: 482 break; 483 484 case -EAGAIN: 485 rehash: 486 mdb = br->mdb; 487 hash = br_ip_hash(mdb, group); 488 break; 489 490 default: 491 goto out; 492 } 493 494 mp = kzalloc(sizeof(*mp), GFP_ATOMIC); 495 if (unlikely(!mp)) 496 goto out; 497 498 mp->br = br; 499 mp->addr = group; 500 setup_timer(&mp->timer, br_multicast_group_expired, 501 (unsigned long)mp); 502 setup_timer(&mp->query_timer, br_multicast_group_query_expired, 503 (unsigned long)mp); 504 505 hlist_add_head_rcu(&mp->hlist[mdb->ver], &mdb->mhash[hash]); 506 mdb->size++; 507 508 out: 509 return mp; 510 } 511 512 static int br_multicast_add_group(struct net_bridge *br, 513 struct net_bridge_port *port, __be32 group) 514 { 515 struct net_bridge_mdb_entry *mp; 516 struct net_bridge_port_group *p; 517 struct net_bridge_port_group **pp; 518 unsigned long now = jiffies; 519 int err; 520 521 if (ipv4_is_local_multicast(group)) 522 return 0; 523 524 spin_lock(&br->multicast_lock); 525 if (!netif_running(br->dev) || 526 (port && port->state == BR_STATE_DISABLED)) 527 goto out; 528 529 mp = br_multicast_new_group(br, port, group); 530 err = PTR_ERR(mp); 531 if (unlikely(IS_ERR(mp) || !mp)) 532 goto err; 533 534 if (!port) { 535 hlist_add_head(&mp->mglist, &br->mglist); 536 mod_timer(&mp->timer, now + br->multicast_membership_interval); 537 goto out; 538 } 539 540 for (pp = &mp->ports; (p = *pp); pp = &p->next) { 541 if (p->port == port) 542 goto found; 543 if ((unsigned long)p->port < (unsigned long)port) 544 break; 545 } 546 547 p = kzalloc(sizeof(*p), GFP_ATOMIC); 548 err = -ENOMEM; 549 if (unlikely(!p)) 550 goto err; 551 552 p->addr = group; 553 p->port = port; 554 p->next = *pp; 555 hlist_add_head(&p->mglist, &port->mglist); 556 setup_timer(&p->timer, br_multicast_port_group_expired, 557 (unsigned long)p); 558 setup_timer(&p->query_timer, br_multicast_port_group_query_expired, 559 (unsigned long)p); 560 561 rcu_assign_pointer(*pp, p); 562 563 found: 564 mod_timer(&p->timer, now + br->multicast_membership_interval); 565 out: 566 err = 0; 567 568 err: 569 spin_unlock(&br->multicast_lock); 570 return err; 571 } 572 573 static void br_multicast_router_expired(unsigned long data) 574 { 575 struct net_bridge_port *port = (void *)data; 576 struct net_bridge *br = port->br; 577 578 spin_lock(&br->multicast_lock); 579 if (port->multicast_router != 1 || 580 timer_pending(&port->multicast_router_timer) || 581 hlist_unhashed(&port->rlist)) 582 goto out; 583 584 hlist_del_init_rcu(&port->rlist); 585 586 out: 587 spin_unlock(&br->multicast_lock); 588 } 589 590 static void br_multicast_local_router_expired(unsigned long data) 591 { 592 } 593 594 static void br_multicast_send_query(struct net_bridge *br, 595 struct net_bridge_port *port, u32 sent) 596 { 597 unsigned long time; 598 struct sk_buff *skb; 599 600 if (!netif_running(br->dev) || br->multicast_disabled || 601 timer_pending(&br->multicast_querier_timer)) 602 return; 603 604 skb = br_multicast_alloc_query(br, 0); 605 if (!skb) 606 goto timer; 607 608 if (port) { 609 __skb_push(skb, sizeof(struct ethhdr)); 610 skb->dev = port->dev; 611 NF_HOOK(PF_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev, 612 dev_queue_xmit); 613 } else 614 netif_rx(skb); 615 616 timer: 617 time = jiffies; 618 time += sent < br->multicast_startup_query_count ? 619 br->multicast_startup_query_interval : 620 br->multicast_query_interval; 621 mod_timer(port ? &port->multicast_query_timer : 622 &br->multicast_query_timer, time); 623 } 624 625 static void br_multicast_port_query_expired(unsigned long data) 626 { 627 struct net_bridge_port *port = (void *)data; 628 struct net_bridge *br = port->br; 629 630 spin_lock(&br->multicast_lock); 631 if (port->state == BR_STATE_DISABLED || 632 port->state == BR_STATE_BLOCKING) 633 goto out; 634 635 if (port->multicast_startup_queries_sent < 636 br->multicast_startup_query_count) 637 port->multicast_startup_queries_sent++; 638 639 br_multicast_send_query(port->br, port, 640 port->multicast_startup_queries_sent); 641 642 out: 643 spin_unlock(&br->multicast_lock); 644 } 645 646 void br_multicast_add_port(struct net_bridge_port *port) 647 { 648 port->multicast_router = 1; 649 650 setup_timer(&port->multicast_router_timer, br_multicast_router_expired, 651 (unsigned long)port); 652 setup_timer(&port->multicast_query_timer, 653 br_multicast_port_query_expired, (unsigned long)port); 654 } 655 656 void br_multicast_del_port(struct net_bridge_port *port) 657 { 658 del_timer_sync(&port->multicast_router_timer); 659 } 660 661 static void __br_multicast_enable_port(struct net_bridge_port *port) 662 { 663 port->multicast_startup_queries_sent = 0; 664 665 if (try_to_del_timer_sync(&port->multicast_query_timer) >= 0 || 666 del_timer(&port->multicast_query_timer)) 667 mod_timer(&port->multicast_query_timer, jiffies); 668 } 669 670 void br_multicast_enable_port(struct net_bridge_port *port) 671 { 672 struct net_bridge *br = port->br; 673 674 spin_lock(&br->multicast_lock); 675 if (br->multicast_disabled || !netif_running(br->dev)) 676 goto out; 677 678 __br_multicast_enable_port(port); 679 680 out: 681 spin_unlock(&br->multicast_lock); 682 } 683 684 void br_multicast_disable_port(struct net_bridge_port *port) 685 { 686 struct net_bridge *br = port->br; 687 struct net_bridge_port_group *pg; 688 struct hlist_node *p, *n; 689 690 spin_lock(&br->multicast_lock); 691 hlist_for_each_entry_safe(pg, p, n, &port->mglist, mglist) 692 br_multicast_del_pg(br, pg); 693 694 if (!hlist_unhashed(&port->rlist)) 695 hlist_del_init_rcu(&port->rlist); 696 del_timer(&port->multicast_router_timer); 697 del_timer(&port->multicast_query_timer); 698 spin_unlock(&br->multicast_lock); 699 } 700 701 static int br_multicast_igmp3_report(struct net_bridge *br, 702 struct net_bridge_port *port, 703 struct sk_buff *skb) 704 { 705 struct igmpv3_report *ih; 706 struct igmpv3_grec *grec; 707 int i; 708 int len; 709 int num; 710 int type; 711 int err = 0; 712 __be32 group; 713 714 if (!pskb_may_pull(skb, sizeof(*ih))) 715 return -EINVAL; 716 717 ih = igmpv3_report_hdr(skb); 718 num = ntohs(ih->ngrec); 719 len = sizeof(*ih); 720 721 for (i = 0; i < num; i++) { 722 len += sizeof(*grec); 723 if (!pskb_may_pull(skb, len)) 724 return -EINVAL; 725 726 grec = (void *)(skb->data + len - sizeof(*grec)); 727 group = grec->grec_mca; 728 type = grec->grec_type; 729 730 len += ntohs(grec->grec_nsrcs) * 4; 731 if (!pskb_may_pull(skb, len)) 732 return -EINVAL; 733 734 /* We treat this as an IGMPv2 report for now. */ 735 switch (type) { 736 case IGMPV3_MODE_IS_INCLUDE: 737 case IGMPV3_MODE_IS_EXCLUDE: 738 case IGMPV3_CHANGE_TO_INCLUDE: 739 case IGMPV3_CHANGE_TO_EXCLUDE: 740 case IGMPV3_ALLOW_NEW_SOURCES: 741 case IGMPV3_BLOCK_OLD_SOURCES: 742 break; 743 744 default: 745 continue; 746 } 747 748 err = br_multicast_add_group(br, port, group); 749 if (err) 750 break; 751 } 752 753 return err; 754 } 755 756 static void br_multicast_add_router(struct net_bridge *br, 757 struct net_bridge_port *port) 758 { 759 struct hlist_node *p; 760 struct hlist_node **h; 761 762 for (h = &br->router_list.first; 763 (p = *h) && 764 (unsigned long)container_of(p, struct net_bridge_port, rlist) > 765 (unsigned long)port; 766 h = &p->next) 767 ; 768 769 port->rlist.pprev = h; 770 port->rlist.next = p; 771 rcu_assign_pointer(*h, &port->rlist); 772 if (p) 773 p->pprev = &port->rlist.next; 774 } 775 776 static void br_multicast_mark_router(struct net_bridge *br, 777 struct net_bridge_port *port) 778 { 779 unsigned long now = jiffies; 780 781 if (!port) { 782 if (br->multicast_router == 1) 783 mod_timer(&br->multicast_router_timer, 784 now + br->multicast_querier_interval); 785 return; 786 } 787 788 if (port->multicast_router != 1) 789 return; 790 791 if (!hlist_unhashed(&port->rlist)) 792 goto timer; 793 794 br_multicast_add_router(br, port); 795 796 timer: 797 mod_timer(&port->multicast_router_timer, 798 now + br->multicast_querier_interval); 799 } 800 801 static void br_multicast_query_received(struct net_bridge *br, 802 struct net_bridge_port *port, 803 __be32 saddr) 804 { 805 if (saddr) 806 mod_timer(&br->multicast_querier_timer, 807 jiffies + br->multicast_querier_interval); 808 else if (timer_pending(&br->multicast_querier_timer)) 809 return; 810 811 br_multicast_mark_router(br, port); 812 } 813 814 static int br_multicast_query(struct net_bridge *br, 815 struct net_bridge_port *port, 816 struct sk_buff *skb) 817 { 818 struct iphdr *iph = ip_hdr(skb); 819 struct igmphdr *ih = igmp_hdr(skb); 820 struct net_bridge_mdb_entry *mp; 821 struct igmpv3_query *ih3; 822 struct net_bridge_port_group *p; 823 struct net_bridge_port_group **pp; 824 unsigned long max_delay; 825 unsigned long now = jiffies; 826 __be32 group; 827 int err = 0; 828 829 spin_lock(&br->multicast_lock); 830 if (!netif_running(br->dev) || 831 (port && port->state == BR_STATE_DISABLED)) 832 goto out; 833 834 br_multicast_query_received(br, port, iph->saddr); 835 836 group = ih->group; 837 838 if (skb->len == sizeof(*ih)) { 839 max_delay = ih->code * (HZ / IGMP_TIMER_SCALE); 840 841 if (!max_delay) { 842 max_delay = 10 * HZ; 843 group = 0; 844 } 845 } else { 846 if (!pskb_may_pull(skb, sizeof(struct igmpv3_query))) { 847 err = -EINVAL; 848 goto out; 849 } 850 851 ih3 = igmpv3_query_hdr(skb); 852 if (ih3->nsrcs) 853 goto out; 854 855 max_delay = ih3->code ? 856 IGMPV3_MRC(ih3->code) * (HZ / IGMP_TIMER_SCALE) : 1; 857 } 858 859 if (!group) 860 goto out; 861 862 mp = br_mdb_ip_get(br->mdb, group); 863 if (!mp) 864 goto out; 865 866 max_delay *= br->multicast_last_member_count; 867 868 if (!hlist_unhashed(&mp->mglist) && 869 (timer_pending(&mp->timer) ? 870 time_after(mp->timer.expires, now + max_delay) : 871 try_to_del_timer_sync(&mp->timer) >= 0)) 872 mod_timer(&mp->timer, now + max_delay); 873 874 for (pp = &mp->ports; (p = *pp); pp = &p->next) { 875 if (timer_pending(&p->timer) ? 876 time_after(p->timer.expires, now + max_delay) : 877 try_to_del_timer_sync(&p->timer) >= 0) 878 mod_timer(&mp->timer, now + max_delay); 879 } 880 881 out: 882 spin_unlock(&br->multicast_lock); 883 return err; 884 } 885 886 static void br_multicast_leave_group(struct net_bridge *br, 887 struct net_bridge_port *port, 888 __be32 group) 889 { 890 struct net_bridge_mdb_htable *mdb; 891 struct net_bridge_mdb_entry *mp; 892 struct net_bridge_port_group *p; 893 unsigned long now; 894 unsigned long time; 895 896 if (ipv4_is_local_multicast(group)) 897 return; 898 899 spin_lock(&br->multicast_lock); 900 if (!netif_running(br->dev) || 901 (port && port->state == BR_STATE_DISABLED) || 902 timer_pending(&br->multicast_querier_timer)) 903 goto out; 904 905 mdb = br->mdb; 906 mp = br_mdb_ip_get(mdb, group); 907 if (!mp) 908 goto out; 909 910 now = jiffies; 911 time = now + br->multicast_last_member_count * 912 br->multicast_last_member_interval; 913 914 if (!port) { 915 if (!hlist_unhashed(&mp->mglist) && 916 (timer_pending(&mp->timer) ? 917 time_after(mp->timer.expires, time) : 918 try_to_del_timer_sync(&mp->timer) >= 0)) { 919 mod_timer(&mp->timer, time); 920 921 mp->queries_sent = 0; 922 mod_timer(&mp->query_timer, now); 923 } 924 925 goto out; 926 } 927 928 for (p = mp->ports; p; p = p->next) { 929 if (p->port != port) 930 continue; 931 932 if (!hlist_unhashed(&p->mglist) && 933 (timer_pending(&p->timer) ? 934 time_after(p->timer.expires, time) : 935 try_to_del_timer_sync(&p->timer) >= 0)) { 936 mod_timer(&p->timer, time); 937 938 p->queries_sent = 0; 939 mod_timer(&p->query_timer, now); 940 } 941 942 break; 943 } 944 945 out: 946 spin_unlock(&br->multicast_lock); 947 } 948 949 static int br_multicast_ipv4_rcv(struct net_bridge *br, 950 struct net_bridge_port *port, 951 struct sk_buff *skb) 952 { 953 struct sk_buff *skb2 = skb; 954 struct iphdr *iph; 955 struct igmphdr *ih; 956 unsigned len; 957 unsigned offset; 958 int err; 959 960 /* We treat OOM as packet loss for now. */ 961 if (!pskb_may_pull(skb, sizeof(*iph))) 962 return -EINVAL; 963 964 iph = ip_hdr(skb); 965 966 if (iph->ihl < 5 || iph->version != 4) 967 return -EINVAL; 968 969 if (!pskb_may_pull(skb, ip_hdrlen(skb))) 970 return -EINVAL; 971 972 iph = ip_hdr(skb); 973 974 if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl))) 975 return -EINVAL; 976 977 if (iph->protocol != IPPROTO_IGMP) 978 return 0; 979 980 len = ntohs(iph->tot_len); 981 if (skb->len < len || len < ip_hdrlen(skb)) 982 return -EINVAL; 983 984 if (skb->len > len) { 985 skb2 = skb_clone(skb, GFP_ATOMIC); 986 if (!skb2) 987 return -ENOMEM; 988 989 err = pskb_trim_rcsum(skb2, len); 990 if (err) 991 goto err_out; 992 } 993 994 len -= ip_hdrlen(skb2); 995 offset = skb_network_offset(skb2) + ip_hdrlen(skb2); 996 __skb_pull(skb2, offset); 997 skb_reset_transport_header(skb2); 998 999 err = -EINVAL; 1000 if (!pskb_may_pull(skb2, sizeof(*ih))) 1001 goto out; 1002 1003 iph = ip_hdr(skb2); 1004 1005 switch (skb2->ip_summed) { 1006 case CHECKSUM_COMPLETE: 1007 if (!csum_fold(skb2->csum)) 1008 break; 1009 /* fall through */ 1010 case CHECKSUM_NONE: 1011 skb2->csum = 0; 1012 if (skb_checksum_complete(skb2)) 1013 goto out; 1014 } 1015 1016 err = 0; 1017 1018 BR_INPUT_SKB_CB(skb)->igmp = 1; 1019 ih = igmp_hdr(skb2); 1020 1021 switch (ih->type) { 1022 case IGMP_HOST_MEMBERSHIP_REPORT: 1023 case IGMPV2_HOST_MEMBERSHIP_REPORT: 1024 BR_INPUT_SKB_CB(skb2)->mrouters_only = 1; 1025 err = br_multicast_add_group(br, port, ih->group); 1026 break; 1027 case IGMPV3_HOST_MEMBERSHIP_REPORT: 1028 err = br_multicast_igmp3_report(br, port, skb2); 1029 break; 1030 case IGMP_HOST_MEMBERSHIP_QUERY: 1031 err = br_multicast_query(br, port, skb2); 1032 break; 1033 case IGMP_HOST_LEAVE_MESSAGE: 1034 br_multicast_leave_group(br, port, ih->group); 1035 break; 1036 } 1037 1038 out: 1039 __skb_push(skb2, offset); 1040 err_out: 1041 if (skb2 != skb) 1042 kfree_skb(skb2); 1043 return err; 1044 } 1045 1046 int br_multicast_rcv(struct net_bridge *br, struct net_bridge_port *port, 1047 struct sk_buff *skb) 1048 { 1049 BR_INPUT_SKB_CB(skb)->igmp = 0; 1050 BR_INPUT_SKB_CB(skb)->mrouters_only = 0; 1051 1052 if (br->multicast_disabled) 1053 return 0; 1054 1055 switch (skb->protocol) { 1056 case htons(ETH_P_IP): 1057 return br_multicast_ipv4_rcv(br, port, skb); 1058 } 1059 1060 return 0; 1061 } 1062 1063 static void br_multicast_query_expired(unsigned long data) 1064 { 1065 struct net_bridge *br = (void *)data; 1066 1067 spin_lock(&br->multicast_lock); 1068 if (br->multicast_startup_queries_sent < 1069 br->multicast_startup_query_count) 1070 br->multicast_startup_queries_sent++; 1071 1072 br_multicast_send_query(br, NULL, br->multicast_startup_queries_sent); 1073 1074 spin_unlock(&br->multicast_lock); 1075 } 1076 1077 void br_multicast_init(struct net_bridge *br) 1078 { 1079 br->hash_elasticity = 4; 1080 br->hash_max = 512; 1081 1082 br->multicast_router = 1; 1083 br->multicast_last_member_count = 2; 1084 br->multicast_startup_query_count = 2; 1085 1086 br->multicast_last_member_interval = HZ; 1087 br->multicast_query_response_interval = 10 * HZ; 1088 br->multicast_startup_query_interval = 125 * HZ / 4; 1089 br->multicast_query_interval = 125 * HZ; 1090 br->multicast_querier_interval = 255 * HZ; 1091 br->multicast_membership_interval = 260 * HZ; 1092 1093 spin_lock_init(&br->multicast_lock); 1094 setup_timer(&br->multicast_router_timer, 1095 br_multicast_local_router_expired, 0); 1096 setup_timer(&br->multicast_querier_timer, 1097 br_multicast_local_router_expired, 0); 1098 setup_timer(&br->multicast_query_timer, br_multicast_query_expired, 1099 (unsigned long)br); 1100 } 1101 1102 void br_multicast_open(struct net_bridge *br) 1103 { 1104 br->multicast_startup_queries_sent = 0; 1105 1106 if (br->multicast_disabled) 1107 return; 1108 1109 mod_timer(&br->multicast_query_timer, jiffies); 1110 } 1111 1112 void br_multicast_stop(struct net_bridge *br) 1113 { 1114 struct net_bridge_mdb_htable *mdb; 1115 struct net_bridge_mdb_entry *mp; 1116 struct hlist_node *p, *n; 1117 u32 ver; 1118 int i; 1119 1120 del_timer_sync(&br->multicast_router_timer); 1121 del_timer_sync(&br->multicast_querier_timer); 1122 del_timer_sync(&br->multicast_query_timer); 1123 1124 spin_lock_bh(&br->multicast_lock); 1125 mdb = br->mdb; 1126 if (!mdb) 1127 goto out; 1128 1129 br->mdb = NULL; 1130 1131 ver = mdb->ver; 1132 for (i = 0; i < mdb->max; i++) { 1133 hlist_for_each_entry_safe(mp, p, n, &mdb->mhash[i], 1134 hlist[ver]) { 1135 del_timer(&mp->timer); 1136 del_timer(&mp->query_timer); 1137 call_rcu_bh(&mp->rcu, br_multicast_free_group); 1138 } 1139 } 1140 1141 if (mdb->old) { 1142 spin_unlock_bh(&br->multicast_lock); 1143 rcu_barrier_bh(); 1144 spin_lock_bh(&br->multicast_lock); 1145 WARN_ON(mdb->old); 1146 } 1147 1148 mdb->old = mdb; 1149 call_rcu_bh(&mdb->rcu, br_mdb_free); 1150 1151 out: 1152 spin_unlock_bh(&br->multicast_lock); 1153 } 1154 1155 int br_multicast_set_router(struct net_bridge *br, unsigned long val) 1156 { 1157 int err = -ENOENT; 1158 1159 spin_lock_bh(&br->multicast_lock); 1160 if (!netif_running(br->dev)) 1161 goto unlock; 1162 1163 switch (val) { 1164 case 0: 1165 case 2: 1166 del_timer(&br->multicast_router_timer); 1167 /* fall through */ 1168 case 1: 1169 br->multicast_router = val; 1170 err = 0; 1171 break; 1172 1173 default: 1174 err = -EINVAL; 1175 break; 1176 } 1177 1178 unlock: 1179 spin_unlock_bh(&br->multicast_lock); 1180 1181 return err; 1182 } 1183 1184 int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val) 1185 { 1186 struct net_bridge *br = p->br; 1187 int err = -ENOENT; 1188 1189 spin_lock(&br->multicast_lock); 1190 if (!netif_running(br->dev) || p->state == BR_STATE_DISABLED) 1191 goto unlock; 1192 1193 switch (val) { 1194 case 0: 1195 case 1: 1196 case 2: 1197 p->multicast_router = val; 1198 err = 0; 1199 1200 if (val < 2 && !hlist_unhashed(&p->rlist)) 1201 hlist_del_init_rcu(&p->rlist); 1202 1203 if (val == 1) 1204 break; 1205 1206 del_timer(&p->multicast_router_timer); 1207 1208 if (val == 0) 1209 break; 1210 1211 br_multicast_add_router(br, p); 1212 break; 1213 1214 default: 1215 err = -EINVAL; 1216 break; 1217 } 1218 1219 unlock: 1220 spin_unlock(&br->multicast_lock); 1221 1222 return err; 1223 } 1224 1225 int br_multicast_toggle(struct net_bridge *br, unsigned long val) 1226 { 1227 struct net_bridge_port *port; 1228 int err = -ENOENT; 1229 1230 spin_lock(&br->multicast_lock); 1231 if (!netif_running(br->dev)) 1232 goto unlock; 1233 1234 err = 0; 1235 if (br->multicast_disabled == !val) 1236 goto unlock; 1237 1238 br->multicast_disabled = !val; 1239 if (br->multicast_disabled) 1240 goto unlock; 1241 1242 if (br->mdb) { 1243 if (br->mdb->old) { 1244 err = -EEXIST; 1245 rollback: 1246 br->multicast_disabled = !!val; 1247 goto unlock; 1248 } 1249 1250 err = br_mdb_rehash(&br->mdb, br->mdb->max, 1251 br->hash_elasticity); 1252 if (err) 1253 goto rollback; 1254 } 1255 1256 br_multicast_open(br); 1257 list_for_each_entry(port, &br->port_list, list) { 1258 if (port->state == BR_STATE_DISABLED || 1259 port->state == BR_STATE_BLOCKING) 1260 continue; 1261 1262 __br_multicast_enable_port(port); 1263 } 1264 1265 unlock: 1266 spin_unlock(&br->multicast_lock); 1267 1268 return err; 1269 } 1270 1271 int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val) 1272 { 1273 int err = -ENOENT; 1274 u32 old; 1275 1276 spin_lock(&br->multicast_lock); 1277 if (!netif_running(br->dev)) 1278 goto unlock; 1279 1280 err = -EINVAL; 1281 if (!is_power_of_2(val)) 1282 goto unlock; 1283 if (br->mdb && val < br->mdb->size) 1284 goto unlock; 1285 1286 err = 0; 1287 1288 old = br->hash_max; 1289 br->hash_max = val; 1290 1291 if (br->mdb) { 1292 if (br->mdb->old) { 1293 err = -EEXIST; 1294 rollback: 1295 br->hash_max = old; 1296 goto unlock; 1297 } 1298 1299 err = br_mdb_rehash(&br->mdb, br->hash_max, 1300 br->hash_elasticity); 1301 if (err) 1302 goto rollback; 1303 } 1304 1305 unlock: 1306 spin_unlock(&br->multicast_lock); 1307 1308 return err; 1309 } 1310