1 /* Copyright (C) 2014-2015 B.A.T.M.A.N. contributors: 2 * 3 * Linus Lüssing 4 * 5 * This program is free software; you can redistribute it and/or 6 * modify it under the terms of version 2 of the GNU General Public 7 * License as published by the Free Software Foundation. 8 * 9 * This program is distributed in the hope that it will be useful, but 10 * WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 * General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, see <http://www.gnu.org/licenses/>. 16 */ 17 18 #include "multicast.h" 19 #include "main.h" 20 21 #include <linux/atomic.h> 22 #include <linux/bitops.h> 23 #include <linux/bug.h> 24 #include <linux/byteorder/generic.h> 25 #include <linux/errno.h> 26 #include <linux/etherdevice.h> 27 #include <linux/fs.h> 28 #include <linux/if_ether.h> 29 #include <linux/in6.h> 30 #include <linux/in.h> 31 #include <linux/ip.h> 32 #include <linux/ipv6.h> 33 #include <linux/list.h> 34 #include <linux/lockdep.h> 35 #include <linux/netdevice.h> 36 #include <linux/rculist.h> 37 #include <linux/rcupdate.h> 38 #include <linux/skbuff.h> 39 #include <linux/slab.h> 40 #include <linux/spinlock.h> 41 #include <linux/stddef.h> 42 #include <linux/string.h> 43 #include <linux/types.h> 44 #include <net/addrconf.h> 45 #include <net/ipv6.h> 46 47 #include "packet.h" 48 #include "translation-table.h" 49 50 /** 51 * batadv_mcast_mla_softif_get - get softif multicast listeners 52 * @dev: the device to collect multicast addresses from 53 * @mcast_list: a list to put found addresses into 54 * 55 * Collect multicast addresses of the local multicast listeners 56 * on the given soft interface, dev, in the given mcast_list. 57 * 58 * Returns -ENOMEM on memory allocation error or the number of 59 * items added to the mcast_list otherwise. 60 */ 61 static int batadv_mcast_mla_softif_get(struct net_device *dev, 62 struct hlist_head *mcast_list) 63 { 64 struct netdev_hw_addr *mc_list_entry; 65 struct batadv_hw_addr *new; 66 int ret = 0; 67 68 netif_addr_lock_bh(dev); 69 netdev_for_each_mc_addr(mc_list_entry, dev) { 70 new = kmalloc(sizeof(*new), GFP_ATOMIC); 71 if (!new) { 72 ret = -ENOMEM; 73 break; 74 } 75 76 ether_addr_copy(new->addr, mc_list_entry->addr); 77 hlist_add_head(&new->list, mcast_list); 78 ret++; 79 } 80 netif_addr_unlock_bh(dev); 81 82 return ret; 83 } 84 85 /** 86 * batadv_mcast_mla_is_duplicate - check whether an address is in a list 87 * @mcast_addr: the multicast address to check 88 * @mcast_list: the list with multicast addresses to search in 89 * 90 * Returns true if the given address is already in the given list. 91 * Otherwise returns false. 92 */ 93 static bool batadv_mcast_mla_is_duplicate(u8 *mcast_addr, 94 struct hlist_head *mcast_list) 95 { 96 struct batadv_hw_addr *mcast_entry; 97 98 hlist_for_each_entry(mcast_entry, mcast_list, list) 99 if (batadv_compare_eth(mcast_entry->addr, mcast_addr)) 100 return true; 101 102 return false; 103 } 104 105 /** 106 * batadv_mcast_mla_list_free - free a list of multicast addresses 107 * @bat_priv: the bat priv with all the soft interface information 108 * @mcast_list: the list to free 109 * 110 * Removes and frees all items in the given mcast_list. 111 */ 112 static void batadv_mcast_mla_list_free(struct batadv_priv *bat_priv, 113 struct hlist_head *mcast_list) 114 { 115 struct batadv_hw_addr *mcast_entry; 116 struct hlist_node *tmp; 117 118 lockdep_assert_held(&bat_priv->tt.commit_lock); 119 120 hlist_for_each_entry_safe(mcast_entry, tmp, mcast_list, list) { 121 hlist_del(&mcast_entry->list); 122 kfree(mcast_entry); 123 } 124 } 125 126 /** 127 * batadv_mcast_mla_tt_retract - clean up multicast listener announcements 128 * @bat_priv: the bat priv with all the soft interface information 129 * @mcast_list: a list of addresses which should _not_ be removed 130 * 131 * Retracts the announcement of any multicast listener from the 132 * translation table except the ones listed in the given mcast_list. 133 * 134 * If mcast_list is NULL then all are retracted. 135 */ 136 static void batadv_mcast_mla_tt_retract(struct batadv_priv *bat_priv, 137 struct hlist_head *mcast_list) 138 { 139 struct batadv_hw_addr *mcast_entry; 140 struct hlist_node *tmp; 141 142 lockdep_assert_held(&bat_priv->tt.commit_lock); 143 144 hlist_for_each_entry_safe(mcast_entry, tmp, &bat_priv->mcast.mla_list, 145 list) { 146 if (mcast_list && 147 batadv_mcast_mla_is_duplicate(mcast_entry->addr, 148 mcast_list)) 149 continue; 150 151 batadv_tt_local_remove(bat_priv, mcast_entry->addr, 152 BATADV_NO_FLAGS, 153 "mcast TT outdated", false); 154 155 hlist_del(&mcast_entry->list); 156 kfree(mcast_entry); 157 } 158 } 159 160 /** 161 * batadv_mcast_mla_tt_add - add multicast listener announcements 162 * @bat_priv: the bat priv with all the soft interface information 163 * @mcast_list: a list of addresses which are going to get added 164 * 165 * Adds multicast listener announcements from the given mcast_list to the 166 * translation table if they have not been added yet. 167 */ 168 static void batadv_mcast_mla_tt_add(struct batadv_priv *bat_priv, 169 struct hlist_head *mcast_list) 170 { 171 struct batadv_hw_addr *mcast_entry; 172 struct hlist_node *tmp; 173 174 lockdep_assert_held(&bat_priv->tt.commit_lock); 175 176 if (!mcast_list) 177 return; 178 179 hlist_for_each_entry_safe(mcast_entry, tmp, mcast_list, list) { 180 if (batadv_mcast_mla_is_duplicate(mcast_entry->addr, 181 &bat_priv->mcast.mla_list)) 182 continue; 183 184 if (!batadv_tt_local_add(bat_priv->soft_iface, 185 mcast_entry->addr, BATADV_NO_FLAGS, 186 BATADV_NULL_IFINDEX, BATADV_NO_MARK)) 187 continue; 188 189 hlist_del(&mcast_entry->list); 190 hlist_add_head(&mcast_entry->list, &bat_priv->mcast.mla_list); 191 } 192 } 193 194 /** 195 * batadv_mcast_has_bridge - check whether the soft-iface is bridged 196 * @bat_priv: the bat priv with all the soft interface information 197 * 198 * Checks whether there is a bridge on top of our soft interface. Returns 199 * true if so, false otherwise. 200 */ 201 static bool batadv_mcast_has_bridge(struct batadv_priv *bat_priv) 202 { 203 struct net_device *upper = bat_priv->soft_iface; 204 205 rcu_read_lock(); 206 do { 207 upper = netdev_master_upper_dev_get_rcu(upper); 208 } while (upper && !(upper->priv_flags & IFF_EBRIDGE)); 209 rcu_read_unlock(); 210 211 return upper; 212 } 213 214 /** 215 * batadv_mcast_mla_tvlv_update - update multicast tvlv 216 * @bat_priv: the bat priv with all the soft interface information 217 * 218 * Updates the own multicast tvlv with our current multicast related settings, 219 * capabilities and inabilities. 220 * 221 * Returns true if the tvlv container is registered afterwards. Otherwise 222 * returns false. 223 */ 224 static bool batadv_mcast_mla_tvlv_update(struct batadv_priv *bat_priv) 225 { 226 struct batadv_tvlv_mcast_data mcast_data; 227 228 mcast_data.flags = BATADV_NO_FLAGS; 229 memset(mcast_data.reserved, 0, sizeof(mcast_data.reserved)); 230 231 /* Avoid attaching MLAs, if there is a bridge on top of our soft 232 * interface, we don't support that yet (TODO) 233 */ 234 if (batadv_mcast_has_bridge(bat_priv)) { 235 if (bat_priv->mcast.enabled) { 236 batadv_tvlv_container_unregister(bat_priv, 237 BATADV_TVLV_MCAST, 1); 238 bat_priv->mcast.enabled = false; 239 } 240 241 return false; 242 } 243 244 if (!bat_priv->mcast.enabled || 245 mcast_data.flags != bat_priv->mcast.flags) { 246 batadv_tvlv_container_register(bat_priv, BATADV_TVLV_MCAST, 1, 247 &mcast_data, sizeof(mcast_data)); 248 bat_priv->mcast.flags = mcast_data.flags; 249 bat_priv->mcast.enabled = true; 250 } 251 252 return true; 253 } 254 255 /** 256 * batadv_mcast_mla_update - update the own MLAs 257 * @bat_priv: the bat priv with all the soft interface information 258 * 259 * Updates the own multicast listener announcements in the translation 260 * table as well as the own, announced multicast tvlv container. 261 */ 262 void batadv_mcast_mla_update(struct batadv_priv *bat_priv) 263 { 264 struct net_device *soft_iface = bat_priv->soft_iface; 265 struct hlist_head mcast_list = HLIST_HEAD_INIT; 266 int ret; 267 268 if (!batadv_mcast_mla_tvlv_update(bat_priv)) 269 goto update; 270 271 ret = batadv_mcast_mla_softif_get(soft_iface, &mcast_list); 272 if (ret < 0) 273 goto out; 274 275 update: 276 batadv_mcast_mla_tt_retract(bat_priv, &mcast_list); 277 batadv_mcast_mla_tt_add(bat_priv, &mcast_list); 278 279 out: 280 batadv_mcast_mla_list_free(bat_priv, &mcast_list); 281 } 282 283 /** 284 * batadv_mcast_forw_mode_check_ipv4 - check for optimized forwarding potential 285 * @bat_priv: the bat priv with all the soft interface information 286 * @skb: the IPv4 packet to check 287 * @is_unsnoopable: stores whether the destination is snoopable 288 * 289 * Checks whether the given IPv4 packet has the potential to be forwarded with a 290 * mode more optimal than classic flooding. 291 * 292 * If so then returns 0. Otherwise -EINVAL is returned or -ENOMEM in case of 293 * memory allocation failure. 294 */ 295 static int batadv_mcast_forw_mode_check_ipv4(struct batadv_priv *bat_priv, 296 struct sk_buff *skb, 297 bool *is_unsnoopable) 298 { 299 struct iphdr *iphdr; 300 301 /* We might fail due to out-of-memory -> drop it */ 302 if (!pskb_may_pull(skb, sizeof(struct ethhdr) + sizeof(*iphdr))) 303 return -ENOMEM; 304 305 iphdr = ip_hdr(skb); 306 307 /* TODO: Implement Multicast Router Discovery (RFC4286), 308 * then allow scope > link local, too 309 */ 310 if (!ipv4_is_local_multicast(iphdr->daddr)) 311 return -EINVAL; 312 313 /* link-local multicast listeners behind a bridge are 314 * not snoopable (see RFC4541, section 2.1.2.2) 315 */ 316 *is_unsnoopable = true; 317 318 return 0; 319 } 320 321 /** 322 * batadv_mcast_forw_mode_check_ipv6 - check for optimized forwarding potential 323 * @bat_priv: the bat priv with all the soft interface information 324 * @skb: the IPv6 packet to check 325 * @is_unsnoopable: stores whether the destination is snoopable 326 * 327 * Checks whether the given IPv6 packet has the potential to be forwarded with a 328 * mode more optimal than classic flooding. 329 * 330 * If so then returns 0. Otherwise -EINVAL is returned or -ENOMEM if we are out 331 * of memory. 332 */ 333 static int batadv_mcast_forw_mode_check_ipv6(struct batadv_priv *bat_priv, 334 struct sk_buff *skb, 335 bool *is_unsnoopable) 336 { 337 struct ipv6hdr *ip6hdr; 338 339 /* We might fail due to out-of-memory -> drop it */ 340 if (!pskb_may_pull(skb, sizeof(struct ethhdr) + sizeof(*ip6hdr))) 341 return -ENOMEM; 342 343 ip6hdr = ipv6_hdr(skb); 344 345 /* TODO: Implement Multicast Router Discovery (RFC4286), 346 * then allow scope > link local, too 347 */ 348 if (IPV6_ADDR_MC_SCOPE(&ip6hdr->daddr) != IPV6_ADDR_SCOPE_LINKLOCAL) 349 return -EINVAL; 350 351 /* link-local-all-nodes multicast listeners behind a bridge are 352 * not snoopable (see RFC4541, section 3, paragraph 3) 353 */ 354 if (ipv6_addr_is_ll_all_nodes(&ip6hdr->daddr)) 355 *is_unsnoopable = true; 356 357 return 0; 358 } 359 360 /** 361 * batadv_mcast_forw_mode_check - check for optimized forwarding potential 362 * @bat_priv: the bat priv with all the soft interface information 363 * @skb: the multicast frame to check 364 * @is_unsnoopable: stores whether the destination is snoopable 365 * 366 * Checks whether the given multicast ethernet frame has the potential to be 367 * forwarded with a mode more optimal than classic flooding. 368 * 369 * If so then returns 0. Otherwise -EINVAL is returned or -ENOMEM if we are out 370 * of memory. 371 */ 372 static int batadv_mcast_forw_mode_check(struct batadv_priv *bat_priv, 373 struct sk_buff *skb, 374 bool *is_unsnoopable) 375 { 376 struct ethhdr *ethhdr = eth_hdr(skb); 377 378 if (!atomic_read(&bat_priv->multicast_mode)) 379 return -EINVAL; 380 381 if (atomic_read(&bat_priv->mcast.num_disabled)) 382 return -EINVAL; 383 384 switch (ntohs(ethhdr->h_proto)) { 385 case ETH_P_IP: 386 return batadv_mcast_forw_mode_check_ipv4(bat_priv, skb, 387 is_unsnoopable); 388 case ETH_P_IPV6: 389 return batadv_mcast_forw_mode_check_ipv6(bat_priv, skb, 390 is_unsnoopable); 391 default: 392 return -EINVAL; 393 } 394 } 395 396 /** 397 * batadv_mcast_want_all_ip_count - count nodes with unspecific mcast interest 398 * @bat_priv: the bat priv with all the soft interface information 399 * @ethhdr: ethernet header of a packet 400 * 401 * Returns the number of nodes which want all IPv4 multicast traffic if the 402 * given ethhdr is from an IPv4 packet or the number of nodes which want all 403 * IPv6 traffic if it matches an IPv6 packet. 404 */ 405 static int batadv_mcast_forw_want_all_ip_count(struct batadv_priv *bat_priv, 406 struct ethhdr *ethhdr) 407 { 408 switch (ntohs(ethhdr->h_proto)) { 409 case ETH_P_IP: 410 return atomic_read(&bat_priv->mcast.num_want_all_ipv4); 411 case ETH_P_IPV6: 412 return atomic_read(&bat_priv->mcast.num_want_all_ipv6); 413 default: 414 /* we shouldn't be here... */ 415 return 0; 416 } 417 } 418 419 /** 420 * batadv_mcast_forw_tt_node_get - get a multicast tt node 421 * @bat_priv: the bat priv with all the soft interface information 422 * @ethhdr: the ether header containing the multicast destination 423 * 424 * Returns an orig_node matching the multicast address provided by ethhdr 425 * via a translation table lookup. This increases the returned nodes refcount. 426 */ 427 static struct batadv_orig_node * 428 batadv_mcast_forw_tt_node_get(struct batadv_priv *bat_priv, 429 struct ethhdr *ethhdr) 430 { 431 return batadv_transtable_search(bat_priv, ethhdr->h_source, 432 ethhdr->h_dest, BATADV_NO_FLAGS); 433 } 434 435 /** 436 * batadv_mcast_want_forw_ipv4_node_get - get a node with an ipv4 flag 437 * @bat_priv: the bat priv with all the soft interface information 438 * 439 * Returns an orig_node which has the BATADV_MCAST_WANT_ALL_IPV4 flag set and 440 * increases its refcount. 441 */ 442 static struct batadv_orig_node * 443 batadv_mcast_forw_ipv4_node_get(struct batadv_priv *bat_priv) 444 { 445 struct batadv_orig_node *tmp_orig_node, *orig_node = NULL; 446 447 rcu_read_lock(); 448 hlist_for_each_entry_rcu(tmp_orig_node, 449 &bat_priv->mcast.want_all_ipv4_list, 450 mcast_want_all_ipv4_node) { 451 if (!atomic_inc_not_zero(&tmp_orig_node->refcount)) 452 continue; 453 454 orig_node = tmp_orig_node; 455 break; 456 } 457 rcu_read_unlock(); 458 459 return orig_node; 460 } 461 462 /** 463 * batadv_mcast_want_forw_ipv6_node_get - get a node with an ipv6 flag 464 * @bat_priv: the bat priv with all the soft interface information 465 * 466 * Returns an orig_node which has the BATADV_MCAST_WANT_ALL_IPV6 flag set 467 * and increases its refcount. 468 */ 469 static struct batadv_orig_node * 470 batadv_mcast_forw_ipv6_node_get(struct batadv_priv *bat_priv) 471 { 472 struct batadv_orig_node *tmp_orig_node, *orig_node = NULL; 473 474 rcu_read_lock(); 475 hlist_for_each_entry_rcu(tmp_orig_node, 476 &bat_priv->mcast.want_all_ipv6_list, 477 mcast_want_all_ipv6_node) { 478 if (!atomic_inc_not_zero(&tmp_orig_node->refcount)) 479 continue; 480 481 orig_node = tmp_orig_node; 482 break; 483 } 484 rcu_read_unlock(); 485 486 return orig_node; 487 } 488 489 /** 490 * batadv_mcast_want_forw_ip_node_get - get a node with an ipv4/ipv6 flag 491 * @bat_priv: the bat priv with all the soft interface information 492 * @ethhdr: an ethernet header to determine the protocol family from 493 * 494 * Returns an orig_node which has the BATADV_MCAST_WANT_ALL_IPV4 or 495 * BATADV_MCAST_WANT_ALL_IPV6 flag, depending on the provided ethhdr, set and 496 * increases its refcount. 497 */ 498 static struct batadv_orig_node * 499 batadv_mcast_forw_ip_node_get(struct batadv_priv *bat_priv, 500 struct ethhdr *ethhdr) 501 { 502 switch (ntohs(ethhdr->h_proto)) { 503 case ETH_P_IP: 504 return batadv_mcast_forw_ipv4_node_get(bat_priv); 505 case ETH_P_IPV6: 506 return batadv_mcast_forw_ipv6_node_get(bat_priv); 507 default: 508 /* we shouldn't be here... */ 509 return NULL; 510 } 511 } 512 513 /** 514 * batadv_mcast_want_forw_unsnoop_node_get - get a node with an unsnoopable flag 515 * @bat_priv: the bat priv with all the soft interface information 516 * 517 * Returns an orig_node which has the BATADV_MCAST_WANT_ALL_UNSNOOPABLES flag 518 * set and increases its refcount. 519 */ 520 static struct batadv_orig_node * 521 batadv_mcast_forw_unsnoop_node_get(struct batadv_priv *bat_priv) 522 { 523 struct batadv_orig_node *tmp_orig_node, *orig_node = NULL; 524 525 rcu_read_lock(); 526 hlist_for_each_entry_rcu(tmp_orig_node, 527 &bat_priv->mcast.want_all_unsnoopables_list, 528 mcast_want_all_unsnoopables_node) { 529 if (!atomic_inc_not_zero(&tmp_orig_node->refcount)) 530 continue; 531 532 orig_node = tmp_orig_node; 533 break; 534 } 535 rcu_read_unlock(); 536 537 return orig_node; 538 } 539 540 /** 541 * batadv_mcast_forw_mode - check on how to forward a multicast packet 542 * @bat_priv: the bat priv with all the soft interface information 543 * @skb: The multicast packet to check 544 * @orig: an originator to be set to forward the skb to 545 * 546 * Returns the forwarding mode as enum batadv_forw_mode and in case of 547 * BATADV_FORW_SINGLE set the orig to the single originator the skb 548 * should be forwarded to. 549 */ 550 enum batadv_forw_mode 551 batadv_mcast_forw_mode(struct batadv_priv *bat_priv, struct sk_buff *skb, 552 struct batadv_orig_node **orig) 553 { 554 int ret, tt_count, ip_count, unsnoop_count, total_count; 555 bool is_unsnoopable = false; 556 struct ethhdr *ethhdr; 557 558 ret = batadv_mcast_forw_mode_check(bat_priv, skb, &is_unsnoopable); 559 if (ret == -ENOMEM) 560 return BATADV_FORW_NONE; 561 else if (ret < 0) 562 return BATADV_FORW_ALL; 563 564 ethhdr = eth_hdr(skb); 565 566 tt_count = batadv_tt_global_hash_count(bat_priv, ethhdr->h_dest, 567 BATADV_NO_FLAGS); 568 ip_count = batadv_mcast_forw_want_all_ip_count(bat_priv, ethhdr); 569 unsnoop_count = !is_unsnoopable ? 0 : 570 atomic_read(&bat_priv->mcast.num_want_all_unsnoopables); 571 572 total_count = tt_count + ip_count + unsnoop_count; 573 574 switch (total_count) { 575 case 1: 576 if (tt_count) 577 *orig = batadv_mcast_forw_tt_node_get(bat_priv, ethhdr); 578 else if (ip_count) 579 *orig = batadv_mcast_forw_ip_node_get(bat_priv, ethhdr); 580 else if (unsnoop_count) 581 *orig = batadv_mcast_forw_unsnoop_node_get(bat_priv); 582 583 if (*orig) 584 return BATADV_FORW_SINGLE; 585 586 /* fall through */ 587 case 0: 588 return BATADV_FORW_NONE; 589 default: 590 return BATADV_FORW_ALL; 591 } 592 } 593 594 /** 595 * batadv_mcast_want_unsnoop_update - update unsnoop counter and list 596 * @bat_priv: the bat priv with all the soft interface information 597 * @orig: the orig_node which multicast state might have changed of 598 * @mcast_flags: flags indicating the new multicast state 599 * 600 * If the BATADV_MCAST_WANT_ALL_UNSNOOPABLES flag of this originator, 601 * orig, has toggled then this method updates counter and list accordingly. 602 * 603 * Caller needs to hold orig->mcast_handler_lock. 604 */ 605 static void batadv_mcast_want_unsnoop_update(struct batadv_priv *bat_priv, 606 struct batadv_orig_node *orig, 607 u8 mcast_flags) 608 { 609 struct hlist_node *node = &orig->mcast_want_all_unsnoopables_node; 610 struct hlist_head *head = &bat_priv->mcast.want_all_unsnoopables_list; 611 612 lockdep_assert_held(&orig->mcast_handler_lock); 613 614 /* switched from flag unset to set */ 615 if (mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES && 616 !(orig->mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES)) { 617 atomic_inc(&bat_priv->mcast.num_want_all_unsnoopables); 618 619 spin_lock_bh(&bat_priv->mcast.want_lists_lock); 620 /* flag checks above + mcast_handler_lock prevents this */ 621 WARN_ON(!hlist_unhashed(node)); 622 623 hlist_add_head_rcu(node, head); 624 spin_unlock_bh(&bat_priv->mcast.want_lists_lock); 625 /* switched from flag set to unset */ 626 } else if (!(mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) && 627 orig->mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) { 628 atomic_dec(&bat_priv->mcast.num_want_all_unsnoopables); 629 630 spin_lock_bh(&bat_priv->mcast.want_lists_lock); 631 /* flag checks above + mcast_handler_lock prevents this */ 632 WARN_ON(hlist_unhashed(node)); 633 634 hlist_del_init_rcu(node); 635 spin_unlock_bh(&bat_priv->mcast.want_lists_lock); 636 } 637 } 638 639 /** 640 * batadv_mcast_want_ipv4_update - update want-all-ipv4 counter and list 641 * @bat_priv: the bat priv with all the soft interface information 642 * @orig: the orig_node which multicast state might have changed of 643 * @mcast_flags: flags indicating the new multicast state 644 * 645 * If the BATADV_MCAST_WANT_ALL_IPV4 flag of this originator, orig, has 646 * toggled then this method updates counter and list accordingly. 647 * 648 * Caller needs to hold orig->mcast_handler_lock. 649 */ 650 static void batadv_mcast_want_ipv4_update(struct batadv_priv *bat_priv, 651 struct batadv_orig_node *orig, 652 u8 mcast_flags) 653 { 654 struct hlist_node *node = &orig->mcast_want_all_ipv4_node; 655 struct hlist_head *head = &bat_priv->mcast.want_all_ipv4_list; 656 657 lockdep_assert_held(&orig->mcast_handler_lock); 658 659 /* switched from flag unset to set */ 660 if (mcast_flags & BATADV_MCAST_WANT_ALL_IPV4 && 661 !(orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV4)) { 662 atomic_inc(&bat_priv->mcast.num_want_all_ipv4); 663 664 spin_lock_bh(&bat_priv->mcast.want_lists_lock); 665 /* flag checks above + mcast_handler_lock prevents this */ 666 WARN_ON(!hlist_unhashed(node)); 667 668 hlist_add_head_rcu(node, head); 669 spin_unlock_bh(&bat_priv->mcast.want_lists_lock); 670 /* switched from flag set to unset */ 671 } else if (!(mcast_flags & BATADV_MCAST_WANT_ALL_IPV4) && 672 orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV4) { 673 atomic_dec(&bat_priv->mcast.num_want_all_ipv4); 674 675 spin_lock_bh(&bat_priv->mcast.want_lists_lock); 676 /* flag checks above + mcast_handler_lock prevents this */ 677 WARN_ON(hlist_unhashed(node)); 678 679 hlist_del_init_rcu(node); 680 spin_unlock_bh(&bat_priv->mcast.want_lists_lock); 681 } 682 } 683 684 /** 685 * batadv_mcast_want_ipv6_update - update want-all-ipv6 counter and list 686 * @bat_priv: the bat priv with all the soft interface information 687 * @orig: the orig_node which multicast state might have changed of 688 * @mcast_flags: flags indicating the new multicast state 689 * 690 * If the BATADV_MCAST_WANT_ALL_IPV6 flag of this originator, orig, has 691 * toggled then this method updates counter and list accordingly. 692 * 693 * Caller needs to hold orig->mcast_handler_lock. 694 */ 695 static void batadv_mcast_want_ipv6_update(struct batadv_priv *bat_priv, 696 struct batadv_orig_node *orig, 697 u8 mcast_flags) 698 { 699 struct hlist_node *node = &orig->mcast_want_all_ipv6_node; 700 struct hlist_head *head = &bat_priv->mcast.want_all_ipv6_list; 701 702 lockdep_assert_held(&orig->mcast_handler_lock); 703 704 /* switched from flag unset to set */ 705 if (mcast_flags & BATADV_MCAST_WANT_ALL_IPV6 && 706 !(orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV6)) { 707 atomic_inc(&bat_priv->mcast.num_want_all_ipv6); 708 709 spin_lock_bh(&bat_priv->mcast.want_lists_lock); 710 /* flag checks above + mcast_handler_lock prevents this */ 711 WARN_ON(!hlist_unhashed(node)); 712 713 hlist_add_head_rcu(node, head); 714 spin_unlock_bh(&bat_priv->mcast.want_lists_lock); 715 /* switched from flag set to unset */ 716 } else if (!(mcast_flags & BATADV_MCAST_WANT_ALL_IPV6) && 717 orig->mcast_flags & BATADV_MCAST_WANT_ALL_IPV6) { 718 atomic_dec(&bat_priv->mcast.num_want_all_ipv6); 719 720 spin_lock_bh(&bat_priv->mcast.want_lists_lock); 721 /* flag checks above + mcast_handler_lock prevents this */ 722 WARN_ON(hlist_unhashed(node)); 723 724 hlist_del_init_rcu(node); 725 spin_unlock_bh(&bat_priv->mcast.want_lists_lock); 726 } 727 } 728 729 /** 730 * batadv_mcast_tvlv_ogm_handler_v1 - process incoming multicast tvlv container 731 * @bat_priv: the bat priv with all the soft interface information 732 * @orig: the orig_node of the ogm 733 * @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags) 734 * @tvlv_value: tvlv buffer containing the multicast data 735 * @tvlv_value_len: tvlv buffer length 736 */ 737 static void batadv_mcast_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv, 738 struct batadv_orig_node *orig, 739 u8 flags, 740 void *tvlv_value, 741 u16 tvlv_value_len) 742 { 743 bool orig_mcast_enabled = !(flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND); 744 u8 mcast_flags = BATADV_NO_FLAGS; 745 bool orig_initialized; 746 747 if (orig_mcast_enabled && tvlv_value && 748 (tvlv_value_len >= sizeof(mcast_flags))) 749 mcast_flags = *(u8 *)tvlv_value; 750 751 spin_lock_bh(&orig->mcast_handler_lock); 752 orig_initialized = test_bit(BATADV_ORIG_CAPA_HAS_MCAST, 753 &orig->capa_initialized); 754 755 /* If mcast support is turned on decrease the disabled mcast node 756 * counter only if we had increased it for this node before. If this 757 * is a completely new orig_node no need to decrease the counter. 758 */ 759 if (orig_mcast_enabled && 760 !test_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities)) { 761 if (orig_initialized) 762 atomic_dec(&bat_priv->mcast.num_disabled); 763 set_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities); 764 /* If mcast support is being switched off or if this is an initial 765 * OGM without mcast support then increase the disabled mcast 766 * node counter. 767 */ 768 } else if (!orig_mcast_enabled && 769 (test_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities) || 770 !orig_initialized)) { 771 atomic_inc(&bat_priv->mcast.num_disabled); 772 clear_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities); 773 } 774 775 set_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capa_initialized); 776 777 batadv_mcast_want_unsnoop_update(bat_priv, orig, mcast_flags); 778 batadv_mcast_want_ipv4_update(bat_priv, orig, mcast_flags); 779 batadv_mcast_want_ipv6_update(bat_priv, orig, mcast_flags); 780 781 orig->mcast_flags = mcast_flags; 782 spin_unlock_bh(&orig->mcast_handler_lock); 783 } 784 785 /** 786 * batadv_mcast_init - initialize the multicast optimizations structures 787 * @bat_priv: the bat priv with all the soft interface information 788 */ 789 void batadv_mcast_init(struct batadv_priv *bat_priv) 790 { 791 batadv_tvlv_handler_register(bat_priv, batadv_mcast_tvlv_ogm_handler_v1, 792 NULL, BATADV_TVLV_MCAST, 1, 793 BATADV_TVLV_HANDLER_OGM_CIFNOTFND); 794 } 795 796 /** 797 * batadv_mcast_free - free the multicast optimizations structures 798 * @bat_priv: the bat priv with all the soft interface information 799 */ 800 void batadv_mcast_free(struct batadv_priv *bat_priv) 801 { 802 batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_MCAST, 1); 803 batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_MCAST, 1); 804 805 spin_lock_bh(&bat_priv->tt.commit_lock); 806 batadv_mcast_mla_tt_retract(bat_priv, NULL); 807 spin_unlock_bh(&bat_priv->tt.commit_lock); 808 } 809 810 /** 811 * batadv_mcast_purge_orig - reset originator global mcast state modifications 812 * @orig: the originator which is going to get purged 813 */ 814 void batadv_mcast_purge_orig(struct batadv_orig_node *orig) 815 { 816 struct batadv_priv *bat_priv = orig->bat_priv; 817 818 spin_lock_bh(&orig->mcast_handler_lock); 819 820 if (!test_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capabilities) && 821 test_bit(BATADV_ORIG_CAPA_HAS_MCAST, &orig->capa_initialized)) 822 atomic_dec(&bat_priv->mcast.num_disabled); 823 824 batadv_mcast_want_unsnoop_update(bat_priv, orig, BATADV_NO_FLAGS); 825 batadv_mcast_want_ipv4_update(bat_priv, orig, BATADV_NO_FLAGS); 826 batadv_mcast_want_ipv6_update(bat_priv, orig, BATADV_NO_FLAGS); 827 828 spin_unlock_bh(&orig->mcast_handler_lock); 829 } 830