1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Forwarding database 4 * Linux ethernet bridge 5 * 6 * Authors: 7 * Lennert Buytenhek <buytenh@gnu.org> 8 */ 9 10 #include <linux/kernel.h> 11 #include <linux/init.h> 12 #include <linux/rculist.h> 13 #include <linux/spinlock.h> 14 #include <linux/times.h> 15 #include <linux/netdevice.h> 16 #include <linux/etherdevice.h> 17 #include <linux/jhash.h> 18 #include <linux/random.h> 19 #include <linux/slab.h> 20 #include <linux/atomic.h> 21 #include <asm/unaligned.h> 22 #include <linux/if_vlan.h> 23 #include <net/switchdev.h> 24 #include <trace/events/bridge.h> 25 #include "br_private.h" 26 27 static const struct rhashtable_params br_fdb_rht_params = { 28 .head_offset = offsetof(struct net_bridge_fdb_entry, rhnode), 29 .key_offset = offsetof(struct net_bridge_fdb_entry, key), 30 .key_len = sizeof(struct net_bridge_fdb_key), 31 .automatic_shrinking = true, 32 }; 33 34 static struct kmem_cache *br_fdb_cache __read_mostly; 35 static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source, 36 const unsigned char *addr, u16 vid); 37 static void fdb_notify(struct net_bridge *br, 38 const struct net_bridge_fdb_entry *, int, bool); 39 40 int __init br_fdb_init(void) 41 { 42 br_fdb_cache = kmem_cache_create("bridge_fdb_cache", 43 sizeof(struct net_bridge_fdb_entry), 44 0, 45 SLAB_HWCACHE_ALIGN, NULL); 46 if (!br_fdb_cache) 47 return -ENOMEM; 48 49 return 0; 50 } 51 52 void br_fdb_fini(void) 53 { 54 kmem_cache_destroy(br_fdb_cache); 55 } 56 57 int br_fdb_hash_init(struct net_bridge *br) 58 { 59 return rhashtable_init(&br->fdb_hash_tbl, &br_fdb_rht_params); 60 } 61 62 void br_fdb_hash_fini(struct net_bridge *br) 63 { 64 rhashtable_destroy(&br->fdb_hash_tbl); 65 } 66 67 /* if topology_changing then use forward_delay (default 15 sec) 68 * otherwise keep longer (default 5 minutes) 69 */ 70 static inline unsigned long hold_time(const struct net_bridge *br) 71 { 72 return br->topology_change ? br->forward_delay : br->ageing_time; 73 } 74 75 static inline int has_expired(const struct net_bridge *br, 76 const struct net_bridge_fdb_entry *fdb) 77 { 78 return !fdb->is_static && !fdb->added_by_external_learn && 79 time_before_eq(fdb->updated + hold_time(br), jiffies); 80 } 81 82 static void fdb_rcu_free(struct rcu_head *head) 83 { 84 struct net_bridge_fdb_entry *ent 85 = container_of(head, struct net_bridge_fdb_entry, rcu); 86 kmem_cache_free(br_fdb_cache, ent); 87 } 88 89 static struct net_bridge_fdb_entry *fdb_find_rcu(struct rhashtable *tbl, 90 const unsigned char *addr, 91 __u16 vid) 92 { 93 struct net_bridge_fdb_key key; 94 95 WARN_ON_ONCE(!rcu_read_lock_held()); 96 97 key.vlan_id = vid; 98 memcpy(key.addr.addr, addr, sizeof(key.addr.addr)); 99 100 return rhashtable_lookup(tbl, &key, br_fdb_rht_params); 101 } 102 103 /* requires bridge hash_lock */ 104 static struct net_bridge_fdb_entry *br_fdb_find(struct net_bridge *br, 105 const unsigned char *addr, 106 __u16 vid) 107 { 108 struct net_bridge_fdb_entry *fdb; 109 110 lockdep_assert_held_once(&br->hash_lock); 111 112 rcu_read_lock(); 113 fdb = fdb_find_rcu(&br->fdb_hash_tbl, addr, vid); 114 rcu_read_unlock(); 115 116 return fdb; 117 } 118 119 struct net_device *br_fdb_find_port(const struct net_device *br_dev, 120 const unsigned char *addr, 121 __u16 vid) 122 { 123 struct net_bridge_fdb_entry *f; 124 struct net_device *dev = NULL; 125 struct net_bridge *br; 126 127 ASSERT_RTNL(); 128 129 if (!netif_is_bridge_master(br_dev)) 130 return NULL; 131 132 br = netdev_priv(br_dev); 133 rcu_read_lock(); 134 f = br_fdb_find_rcu(br, addr, vid); 135 if (f && f->dst) 136 dev = f->dst->dev; 137 rcu_read_unlock(); 138 139 return dev; 140 } 141 EXPORT_SYMBOL_GPL(br_fdb_find_port); 142 143 struct net_bridge_fdb_entry *br_fdb_find_rcu(struct net_bridge *br, 144 const unsigned char *addr, 145 __u16 vid) 146 { 147 return fdb_find_rcu(&br->fdb_hash_tbl, addr, vid); 148 } 149 150 /* When a static FDB entry is added, the mac address from the entry is 151 * added to the bridge private HW address list and all required ports 152 * are then updated with the new information. 153 * Called under RTNL. 154 */ 155 static void fdb_add_hw_addr(struct net_bridge *br, const unsigned char *addr) 156 { 157 int err; 158 struct net_bridge_port *p; 159 160 ASSERT_RTNL(); 161 162 list_for_each_entry(p, &br->port_list, list) { 163 if (!br_promisc_port(p)) { 164 err = dev_uc_add(p->dev, addr); 165 if (err) 166 goto undo; 167 } 168 } 169 170 return; 171 undo: 172 list_for_each_entry_continue_reverse(p, &br->port_list, list) { 173 if (!br_promisc_port(p)) 174 dev_uc_del(p->dev, addr); 175 } 176 } 177 178 /* When a static FDB entry is deleted, the HW address from that entry is 179 * also removed from the bridge private HW address list and updates all 180 * the ports with needed information. 181 * Called under RTNL. 182 */ 183 static void fdb_del_hw_addr(struct net_bridge *br, const unsigned char *addr) 184 { 185 struct net_bridge_port *p; 186 187 ASSERT_RTNL(); 188 189 list_for_each_entry(p, &br->port_list, list) { 190 if (!br_promisc_port(p)) 191 dev_uc_del(p->dev, addr); 192 } 193 } 194 195 static void fdb_delete(struct net_bridge *br, struct net_bridge_fdb_entry *f, 196 bool swdev_notify) 197 { 198 trace_fdb_delete(br, f); 199 200 if (f->is_static) 201 fdb_del_hw_addr(br, f->key.addr.addr); 202 203 hlist_del_init_rcu(&f->fdb_node); 204 rhashtable_remove_fast(&br->fdb_hash_tbl, &f->rhnode, 205 br_fdb_rht_params); 206 fdb_notify(br, f, RTM_DELNEIGH, swdev_notify); 207 call_rcu(&f->rcu, fdb_rcu_free); 208 } 209 210 /* Delete a local entry if no other port had the same address. */ 211 static void fdb_delete_local(struct net_bridge *br, 212 const struct net_bridge_port *p, 213 struct net_bridge_fdb_entry *f) 214 { 215 const unsigned char *addr = f->key.addr.addr; 216 struct net_bridge_vlan_group *vg; 217 const struct net_bridge_vlan *v; 218 struct net_bridge_port *op; 219 u16 vid = f->key.vlan_id; 220 221 /* Maybe another port has same hw addr? */ 222 list_for_each_entry(op, &br->port_list, list) { 223 vg = nbp_vlan_group(op); 224 if (op != p && ether_addr_equal(op->dev->dev_addr, addr) && 225 (!vid || br_vlan_find(vg, vid))) { 226 f->dst = op; 227 f->added_by_user = 0; 228 return; 229 } 230 } 231 232 vg = br_vlan_group(br); 233 v = br_vlan_find(vg, vid); 234 /* Maybe bridge device has same hw addr? */ 235 if (p && ether_addr_equal(br->dev->dev_addr, addr) && 236 (!vid || (v && br_vlan_should_use(v)))) { 237 f->dst = NULL; 238 f->added_by_user = 0; 239 return; 240 } 241 242 fdb_delete(br, f, true); 243 } 244 245 void br_fdb_find_delete_local(struct net_bridge *br, 246 const struct net_bridge_port *p, 247 const unsigned char *addr, u16 vid) 248 { 249 struct net_bridge_fdb_entry *f; 250 251 spin_lock_bh(&br->hash_lock); 252 f = br_fdb_find(br, addr, vid); 253 if (f && f->is_local && !f->added_by_user && f->dst == p) 254 fdb_delete_local(br, p, f); 255 spin_unlock_bh(&br->hash_lock); 256 } 257 258 void br_fdb_changeaddr(struct net_bridge_port *p, const unsigned char *newaddr) 259 { 260 struct net_bridge_vlan_group *vg; 261 struct net_bridge_fdb_entry *f; 262 struct net_bridge *br = p->br; 263 struct net_bridge_vlan *v; 264 265 spin_lock_bh(&br->hash_lock); 266 vg = nbp_vlan_group(p); 267 hlist_for_each_entry(f, &br->fdb_list, fdb_node) { 268 if (f->dst == p && f->is_local && !f->added_by_user) { 269 /* delete old one */ 270 fdb_delete_local(br, p, f); 271 272 /* if this port has no vlan information 273 * configured, we can safely be done at 274 * this point. 275 */ 276 if (!vg || !vg->num_vlans) 277 goto insert; 278 } 279 } 280 281 insert: 282 /* insert new address, may fail if invalid address or dup. */ 283 fdb_insert(br, p, newaddr, 0); 284 285 if (!vg || !vg->num_vlans) 286 goto done; 287 288 /* Now add entries for every VLAN configured on the port. 289 * This function runs under RTNL so the bitmap will not change 290 * from under us. 291 */ 292 list_for_each_entry(v, &vg->vlan_list, vlist) 293 fdb_insert(br, p, newaddr, v->vid); 294 295 done: 296 spin_unlock_bh(&br->hash_lock); 297 } 298 299 void br_fdb_change_mac_address(struct net_bridge *br, const u8 *newaddr) 300 { 301 struct net_bridge_vlan_group *vg; 302 struct net_bridge_fdb_entry *f; 303 struct net_bridge_vlan *v; 304 305 spin_lock_bh(&br->hash_lock); 306 307 /* If old entry was unassociated with any port, then delete it. */ 308 f = br_fdb_find(br, br->dev->dev_addr, 0); 309 if (f && f->is_local && !f->dst && !f->added_by_user) 310 fdb_delete_local(br, NULL, f); 311 312 fdb_insert(br, NULL, newaddr, 0); 313 vg = br_vlan_group(br); 314 if (!vg || !vg->num_vlans) 315 goto out; 316 /* Now remove and add entries for every VLAN configured on the 317 * bridge. This function runs under RTNL so the bitmap will not 318 * change from under us. 319 */ 320 list_for_each_entry(v, &vg->vlan_list, vlist) { 321 if (!br_vlan_should_use(v)) 322 continue; 323 f = br_fdb_find(br, br->dev->dev_addr, v->vid); 324 if (f && f->is_local && !f->dst && !f->added_by_user) 325 fdb_delete_local(br, NULL, f); 326 fdb_insert(br, NULL, newaddr, v->vid); 327 } 328 out: 329 spin_unlock_bh(&br->hash_lock); 330 } 331 332 void br_fdb_cleanup(struct work_struct *work) 333 { 334 struct net_bridge *br = container_of(work, struct net_bridge, 335 gc_work.work); 336 struct net_bridge_fdb_entry *f = NULL; 337 unsigned long delay = hold_time(br); 338 unsigned long work_delay = delay; 339 unsigned long now = jiffies; 340 341 /* this part is tricky, in order to avoid blocking learning and 342 * consequently forwarding, we rely on rcu to delete objects with 343 * delayed freeing allowing us to continue traversing 344 */ 345 rcu_read_lock(); 346 hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) { 347 unsigned long this_timer; 348 349 if (f->is_static || f->added_by_external_learn) 350 continue; 351 this_timer = f->updated + delay; 352 if (time_after(this_timer, now)) { 353 work_delay = min(work_delay, this_timer - now); 354 } else { 355 spin_lock_bh(&br->hash_lock); 356 if (!hlist_unhashed(&f->fdb_node)) 357 fdb_delete(br, f, true); 358 spin_unlock_bh(&br->hash_lock); 359 } 360 } 361 rcu_read_unlock(); 362 363 /* Cleanup minimum 10 milliseconds apart */ 364 work_delay = max_t(unsigned long, work_delay, msecs_to_jiffies(10)); 365 mod_delayed_work(system_long_wq, &br->gc_work, work_delay); 366 } 367 368 /* Completely flush all dynamic entries in forwarding database.*/ 369 void br_fdb_flush(struct net_bridge *br) 370 { 371 struct net_bridge_fdb_entry *f; 372 struct hlist_node *tmp; 373 374 spin_lock_bh(&br->hash_lock); 375 hlist_for_each_entry_safe(f, tmp, &br->fdb_list, fdb_node) { 376 if (!f->is_static) 377 fdb_delete(br, f, true); 378 } 379 spin_unlock_bh(&br->hash_lock); 380 } 381 382 /* Flush all entries referring to a specific port. 383 * if do_all is set also flush static entries 384 * if vid is set delete all entries that match the vlan_id 385 */ 386 void br_fdb_delete_by_port(struct net_bridge *br, 387 const struct net_bridge_port *p, 388 u16 vid, 389 int do_all) 390 { 391 struct net_bridge_fdb_entry *f; 392 struct hlist_node *tmp; 393 394 spin_lock_bh(&br->hash_lock); 395 hlist_for_each_entry_safe(f, tmp, &br->fdb_list, fdb_node) { 396 if (f->dst != p) 397 continue; 398 399 if (!do_all) 400 if (f->is_static || (vid && f->key.vlan_id != vid)) 401 continue; 402 403 if (f->is_local) 404 fdb_delete_local(br, p, f); 405 else 406 fdb_delete(br, f, true); 407 } 408 spin_unlock_bh(&br->hash_lock); 409 } 410 411 #if IS_ENABLED(CONFIG_ATM_LANE) 412 /* Interface used by ATM LANE hook to test 413 * if an addr is on some other bridge port */ 414 int br_fdb_test_addr(struct net_device *dev, unsigned char *addr) 415 { 416 struct net_bridge_fdb_entry *fdb; 417 struct net_bridge_port *port; 418 int ret; 419 420 rcu_read_lock(); 421 port = br_port_get_rcu(dev); 422 if (!port) 423 ret = 0; 424 else { 425 fdb = br_fdb_find_rcu(port->br, addr, 0); 426 ret = fdb && fdb->dst && fdb->dst->dev != dev && 427 fdb->dst->state == BR_STATE_FORWARDING; 428 } 429 rcu_read_unlock(); 430 431 return ret; 432 } 433 #endif /* CONFIG_ATM_LANE */ 434 435 /* 436 * Fill buffer with forwarding table records in 437 * the API format. 438 */ 439 int br_fdb_fillbuf(struct net_bridge *br, void *buf, 440 unsigned long maxnum, unsigned long skip) 441 { 442 struct net_bridge_fdb_entry *f; 443 struct __fdb_entry *fe = buf; 444 int num = 0; 445 446 memset(buf, 0, maxnum*sizeof(struct __fdb_entry)); 447 448 rcu_read_lock(); 449 hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) { 450 if (num >= maxnum) 451 break; 452 453 if (has_expired(br, f)) 454 continue; 455 456 /* ignore pseudo entry for local MAC address */ 457 if (!f->dst) 458 continue; 459 460 if (skip) { 461 --skip; 462 continue; 463 } 464 465 /* convert from internal format to API */ 466 memcpy(fe->mac_addr, f->key.addr.addr, ETH_ALEN); 467 468 /* due to ABI compat need to split into hi/lo */ 469 fe->port_no = f->dst->port_no; 470 fe->port_hi = f->dst->port_no >> 8; 471 472 fe->is_local = f->is_local; 473 if (!f->is_static) 474 fe->ageing_timer_value = jiffies_delta_to_clock_t(jiffies - f->updated); 475 ++fe; 476 ++num; 477 } 478 rcu_read_unlock(); 479 480 return num; 481 } 482 483 static struct net_bridge_fdb_entry *fdb_create(struct net_bridge *br, 484 struct net_bridge_port *source, 485 const unsigned char *addr, 486 __u16 vid, 487 unsigned char is_local, 488 unsigned char is_static) 489 { 490 struct net_bridge_fdb_entry *fdb; 491 492 fdb = kmem_cache_alloc(br_fdb_cache, GFP_ATOMIC); 493 if (fdb) { 494 memcpy(fdb->key.addr.addr, addr, ETH_ALEN); 495 fdb->dst = source; 496 fdb->key.vlan_id = vid; 497 fdb->is_local = is_local; 498 fdb->is_static = is_static; 499 fdb->added_by_user = 0; 500 fdb->added_by_external_learn = 0; 501 fdb->offloaded = 0; 502 fdb->is_sticky = 0; 503 fdb->updated = fdb->used = jiffies; 504 if (rhashtable_lookup_insert_fast(&br->fdb_hash_tbl, 505 &fdb->rhnode, 506 br_fdb_rht_params)) { 507 kmem_cache_free(br_fdb_cache, fdb); 508 fdb = NULL; 509 } else { 510 hlist_add_head_rcu(&fdb->fdb_node, &br->fdb_list); 511 } 512 } 513 return fdb; 514 } 515 516 static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source, 517 const unsigned char *addr, u16 vid) 518 { 519 struct net_bridge_fdb_entry *fdb; 520 521 if (!is_valid_ether_addr(addr)) 522 return -EINVAL; 523 524 fdb = br_fdb_find(br, addr, vid); 525 if (fdb) { 526 /* it is okay to have multiple ports with same 527 * address, just use the first one. 528 */ 529 if (fdb->is_local) 530 return 0; 531 br_warn(br, "adding interface %s with same address as a received packet (addr:%pM, vlan:%u)\n", 532 source ? source->dev->name : br->dev->name, addr, vid); 533 fdb_delete(br, fdb, true); 534 } 535 536 fdb = fdb_create(br, source, addr, vid, 1, 1); 537 if (!fdb) 538 return -ENOMEM; 539 540 fdb_add_hw_addr(br, addr); 541 fdb_notify(br, fdb, RTM_NEWNEIGH, true); 542 return 0; 543 } 544 545 /* Add entry for local address of interface */ 546 int br_fdb_insert(struct net_bridge *br, struct net_bridge_port *source, 547 const unsigned char *addr, u16 vid) 548 { 549 int ret; 550 551 spin_lock_bh(&br->hash_lock); 552 ret = fdb_insert(br, source, addr, vid); 553 spin_unlock_bh(&br->hash_lock); 554 return ret; 555 } 556 557 void br_fdb_update(struct net_bridge *br, struct net_bridge_port *source, 558 const unsigned char *addr, u16 vid, bool added_by_user) 559 { 560 struct net_bridge_fdb_entry *fdb; 561 bool fdb_modified = false; 562 563 /* some users want to always flood. */ 564 if (hold_time(br) == 0) 565 return; 566 567 /* ignore packets unless we are using this port */ 568 if (!(source->state == BR_STATE_LEARNING || 569 source->state == BR_STATE_FORWARDING)) 570 return; 571 572 fdb = fdb_find_rcu(&br->fdb_hash_tbl, addr, vid); 573 if (likely(fdb)) { 574 /* attempt to update an entry for a local interface */ 575 if (unlikely(fdb->is_local)) { 576 if (net_ratelimit()) 577 br_warn(br, "received packet on %s with own address as source address (addr:%pM, vlan:%u)\n", 578 source->dev->name, addr, vid); 579 } else { 580 unsigned long now = jiffies; 581 582 /* fastpath: update of existing entry */ 583 if (unlikely(source != fdb->dst && !fdb->is_sticky)) { 584 fdb->dst = source; 585 fdb_modified = true; 586 /* Take over HW learned entry */ 587 if (unlikely(fdb->added_by_external_learn)) 588 fdb->added_by_external_learn = 0; 589 } 590 if (now != fdb->updated) 591 fdb->updated = now; 592 if (unlikely(added_by_user)) 593 fdb->added_by_user = 1; 594 if (unlikely(fdb_modified)) { 595 trace_br_fdb_update(br, source, addr, vid, added_by_user); 596 fdb_notify(br, fdb, RTM_NEWNEIGH, true); 597 } 598 } 599 } else { 600 spin_lock(&br->hash_lock); 601 fdb = fdb_create(br, source, addr, vid, 0, 0); 602 if (fdb) { 603 if (unlikely(added_by_user)) 604 fdb->added_by_user = 1; 605 trace_br_fdb_update(br, source, addr, vid, 606 added_by_user); 607 fdb_notify(br, fdb, RTM_NEWNEIGH, true); 608 } 609 /* else we lose race and someone else inserts 610 * it first, don't bother updating 611 */ 612 spin_unlock(&br->hash_lock); 613 } 614 } 615 616 static int fdb_to_nud(const struct net_bridge *br, 617 const struct net_bridge_fdb_entry *fdb) 618 { 619 if (fdb->is_local) 620 return NUD_PERMANENT; 621 else if (fdb->is_static) 622 return NUD_NOARP; 623 else if (has_expired(br, fdb)) 624 return NUD_STALE; 625 else 626 return NUD_REACHABLE; 627 } 628 629 static int fdb_fill_info(struct sk_buff *skb, const struct net_bridge *br, 630 const struct net_bridge_fdb_entry *fdb, 631 u32 portid, u32 seq, int type, unsigned int flags) 632 { 633 unsigned long now = jiffies; 634 struct nda_cacheinfo ci; 635 struct nlmsghdr *nlh; 636 struct ndmsg *ndm; 637 638 nlh = nlmsg_put(skb, portid, seq, type, sizeof(*ndm), flags); 639 if (nlh == NULL) 640 return -EMSGSIZE; 641 642 ndm = nlmsg_data(nlh); 643 ndm->ndm_family = AF_BRIDGE; 644 ndm->ndm_pad1 = 0; 645 ndm->ndm_pad2 = 0; 646 ndm->ndm_flags = 0; 647 ndm->ndm_type = 0; 648 ndm->ndm_ifindex = fdb->dst ? fdb->dst->dev->ifindex : br->dev->ifindex; 649 ndm->ndm_state = fdb_to_nud(br, fdb); 650 651 if (fdb->offloaded) 652 ndm->ndm_flags |= NTF_OFFLOADED; 653 if (fdb->added_by_external_learn) 654 ndm->ndm_flags |= NTF_EXT_LEARNED; 655 if (fdb->is_sticky) 656 ndm->ndm_flags |= NTF_STICKY; 657 658 if (nla_put(skb, NDA_LLADDR, ETH_ALEN, &fdb->key.addr)) 659 goto nla_put_failure; 660 if (nla_put_u32(skb, NDA_MASTER, br->dev->ifindex)) 661 goto nla_put_failure; 662 ci.ndm_used = jiffies_to_clock_t(now - fdb->used); 663 ci.ndm_confirmed = 0; 664 ci.ndm_updated = jiffies_to_clock_t(now - fdb->updated); 665 ci.ndm_refcnt = 0; 666 if (nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci)) 667 goto nla_put_failure; 668 669 if (fdb->key.vlan_id && nla_put(skb, NDA_VLAN, sizeof(u16), 670 &fdb->key.vlan_id)) 671 goto nla_put_failure; 672 673 nlmsg_end(skb, nlh); 674 return 0; 675 676 nla_put_failure: 677 nlmsg_cancel(skb, nlh); 678 return -EMSGSIZE; 679 } 680 681 static inline size_t fdb_nlmsg_size(void) 682 { 683 return NLMSG_ALIGN(sizeof(struct ndmsg)) 684 + nla_total_size(ETH_ALEN) /* NDA_LLADDR */ 685 + nla_total_size(sizeof(u32)) /* NDA_MASTER */ 686 + nla_total_size(sizeof(u16)) /* NDA_VLAN */ 687 + nla_total_size(sizeof(struct nda_cacheinfo)); 688 } 689 690 static void fdb_notify(struct net_bridge *br, 691 const struct net_bridge_fdb_entry *fdb, int type, 692 bool swdev_notify) 693 { 694 struct net *net = dev_net(br->dev); 695 struct sk_buff *skb; 696 int err = -ENOBUFS; 697 698 if (swdev_notify) 699 br_switchdev_fdb_notify(fdb, type); 700 701 skb = nlmsg_new(fdb_nlmsg_size(), GFP_ATOMIC); 702 if (skb == NULL) 703 goto errout; 704 705 err = fdb_fill_info(skb, br, fdb, 0, 0, type, 0); 706 if (err < 0) { 707 /* -EMSGSIZE implies BUG in fdb_nlmsg_size() */ 708 WARN_ON(err == -EMSGSIZE); 709 kfree_skb(skb); 710 goto errout; 711 } 712 rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC); 713 return; 714 errout: 715 rtnl_set_sk_err(net, RTNLGRP_NEIGH, err); 716 } 717 718 /* Dump information about entries, in response to GETNEIGH */ 719 int br_fdb_dump(struct sk_buff *skb, 720 struct netlink_callback *cb, 721 struct net_device *dev, 722 struct net_device *filter_dev, 723 int *idx) 724 { 725 struct net_bridge *br = netdev_priv(dev); 726 struct net_bridge_fdb_entry *f; 727 int err = 0; 728 729 if (!(dev->priv_flags & IFF_EBRIDGE)) 730 return err; 731 732 if (!filter_dev) { 733 err = ndo_dflt_fdb_dump(skb, cb, dev, NULL, idx); 734 if (err < 0) 735 return err; 736 } 737 738 rcu_read_lock(); 739 hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) { 740 if (*idx < cb->args[2]) 741 goto skip; 742 if (filter_dev && (!f->dst || f->dst->dev != filter_dev)) { 743 if (filter_dev != dev) 744 goto skip; 745 /* !f->dst is a special case for bridge 746 * It means the MAC belongs to the bridge 747 * Therefore need a little more filtering 748 * we only want to dump the !f->dst case 749 */ 750 if (f->dst) 751 goto skip; 752 } 753 if (!filter_dev && f->dst) 754 goto skip; 755 756 err = fdb_fill_info(skb, br, f, 757 NETLINK_CB(cb->skb).portid, 758 cb->nlh->nlmsg_seq, 759 RTM_NEWNEIGH, 760 NLM_F_MULTI); 761 if (err < 0) 762 break; 763 skip: 764 *idx += 1; 765 } 766 rcu_read_unlock(); 767 768 return err; 769 } 770 771 int br_fdb_get(struct sk_buff *skb, 772 struct nlattr *tb[], 773 struct net_device *dev, 774 const unsigned char *addr, 775 u16 vid, u32 portid, u32 seq, 776 struct netlink_ext_ack *extack) 777 { 778 struct net_bridge *br = netdev_priv(dev); 779 struct net_bridge_fdb_entry *f; 780 int err = 0; 781 782 rcu_read_lock(); 783 f = br_fdb_find_rcu(br, addr, vid); 784 if (!f) { 785 NL_SET_ERR_MSG(extack, "Fdb entry not found"); 786 err = -ENOENT; 787 goto errout; 788 } 789 790 err = fdb_fill_info(skb, br, f, portid, seq, 791 RTM_NEWNEIGH, 0); 792 errout: 793 rcu_read_unlock(); 794 return err; 795 } 796 797 /* Update (create or replace) forwarding database entry */ 798 static int fdb_add_entry(struct net_bridge *br, struct net_bridge_port *source, 799 const u8 *addr, u16 state, u16 flags, u16 vid, 800 u8 ndm_flags) 801 { 802 u8 is_sticky = !!(ndm_flags & NTF_STICKY); 803 struct net_bridge_fdb_entry *fdb; 804 bool modified = false; 805 806 /* If the port cannot learn allow only local and static entries */ 807 if (source && !(state & NUD_PERMANENT) && !(state & NUD_NOARP) && 808 !(source->state == BR_STATE_LEARNING || 809 source->state == BR_STATE_FORWARDING)) 810 return -EPERM; 811 812 if (!source && !(state & NUD_PERMANENT)) { 813 pr_info("bridge: RTM_NEWNEIGH %s without NUD_PERMANENT\n", 814 br->dev->name); 815 return -EINVAL; 816 } 817 818 if (is_sticky && (state & NUD_PERMANENT)) 819 return -EINVAL; 820 821 fdb = br_fdb_find(br, addr, vid); 822 if (fdb == NULL) { 823 if (!(flags & NLM_F_CREATE)) 824 return -ENOENT; 825 826 fdb = fdb_create(br, source, addr, vid, 0, 0); 827 if (!fdb) 828 return -ENOMEM; 829 830 modified = true; 831 } else { 832 if (flags & NLM_F_EXCL) 833 return -EEXIST; 834 835 if (fdb->dst != source) { 836 fdb->dst = source; 837 modified = true; 838 } 839 } 840 841 if (fdb_to_nud(br, fdb) != state) { 842 if (state & NUD_PERMANENT) { 843 fdb->is_local = 1; 844 if (!fdb->is_static) { 845 fdb->is_static = 1; 846 fdb_add_hw_addr(br, addr); 847 } 848 } else if (state & NUD_NOARP) { 849 fdb->is_local = 0; 850 if (!fdb->is_static) { 851 fdb->is_static = 1; 852 fdb_add_hw_addr(br, addr); 853 } 854 } else { 855 fdb->is_local = 0; 856 if (fdb->is_static) { 857 fdb->is_static = 0; 858 fdb_del_hw_addr(br, addr); 859 } 860 } 861 862 modified = true; 863 } 864 865 if (is_sticky != fdb->is_sticky) { 866 fdb->is_sticky = is_sticky; 867 modified = true; 868 } 869 870 fdb->added_by_user = 1; 871 872 fdb->used = jiffies; 873 if (modified) { 874 fdb->updated = jiffies; 875 fdb_notify(br, fdb, RTM_NEWNEIGH, true); 876 } 877 878 return 0; 879 } 880 881 static int __br_fdb_add(struct ndmsg *ndm, struct net_bridge *br, 882 struct net_bridge_port *p, const unsigned char *addr, 883 u16 nlh_flags, u16 vid) 884 { 885 int err = 0; 886 887 if (ndm->ndm_flags & NTF_USE) { 888 if (!p) { 889 pr_info("bridge: RTM_NEWNEIGH %s with NTF_USE is not supported\n", 890 br->dev->name); 891 return -EINVAL; 892 } 893 local_bh_disable(); 894 rcu_read_lock(); 895 br_fdb_update(br, p, addr, vid, true); 896 rcu_read_unlock(); 897 local_bh_enable(); 898 } else if (ndm->ndm_flags & NTF_EXT_LEARNED) { 899 err = br_fdb_external_learn_add(br, p, addr, vid, true); 900 } else { 901 spin_lock_bh(&br->hash_lock); 902 err = fdb_add_entry(br, p, addr, ndm->ndm_state, 903 nlh_flags, vid, ndm->ndm_flags); 904 spin_unlock_bh(&br->hash_lock); 905 } 906 907 return err; 908 } 909 910 /* Add new permanent fdb entry with RTM_NEWNEIGH */ 911 int br_fdb_add(struct ndmsg *ndm, struct nlattr *tb[], 912 struct net_device *dev, 913 const unsigned char *addr, u16 vid, u16 nlh_flags, 914 struct netlink_ext_ack *extack) 915 { 916 struct net_bridge_vlan_group *vg; 917 struct net_bridge_port *p = NULL; 918 struct net_bridge_vlan *v; 919 struct net_bridge *br = NULL; 920 int err = 0; 921 922 trace_br_fdb_add(ndm, dev, addr, vid, nlh_flags); 923 924 if (!(ndm->ndm_state & (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE))) { 925 pr_info("bridge: RTM_NEWNEIGH with invalid state %#x\n", ndm->ndm_state); 926 return -EINVAL; 927 } 928 929 if (is_zero_ether_addr(addr)) { 930 pr_info("bridge: RTM_NEWNEIGH with invalid ether address\n"); 931 return -EINVAL; 932 } 933 934 if (dev->priv_flags & IFF_EBRIDGE) { 935 br = netdev_priv(dev); 936 vg = br_vlan_group(br); 937 } else { 938 p = br_port_get_rtnl(dev); 939 if (!p) { 940 pr_info("bridge: RTM_NEWNEIGH %s not a bridge port\n", 941 dev->name); 942 return -EINVAL; 943 } 944 br = p->br; 945 vg = nbp_vlan_group(p); 946 } 947 948 if (vid) { 949 v = br_vlan_find(vg, vid); 950 if (!v || !br_vlan_should_use(v)) { 951 pr_info("bridge: RTM_NEWNEIGH with unconfigured vlan %d on %s\n", vid, dev->name); 952 return -EINVAL; 953 } 954 955 /* VID was specified, so use it. */ 956 err = __br_fdb_add(ndm, br, p, addr, nlh_flags, vid); 957 } else { 958 err = __br_fdb_add(ndm, br, p, addr, nlh_flags, 0); 959 if (err || !vg || !vg->num_vlans) 960 goto out; 961 962 /* We have vlans configured on this port and user didn't 963 * specify a VLAN. To be nice, add/update entry for every 964 * vlan on this port. 965 */ 966 list_for_each_entry(v, &vg->vlan_list, vlist) { 967 if (!br_vlan_should_use(v)) 968 continue; 969 err = __br_fdb_add(ndm, br, p, addr, nlh_flags, v->vid); 970 if (err) 971 goto out; 972 } 973 } 974 975 out: 976 return err; 977 } 978 979 static int fdb_delete_by_addr_and_port(struct net_bridge *br, 980 const struct net_bridge_port *p, 981 const u8 *addr, u16 vlan) 982 { 983 struct net_bridge_fdb_entry *fdb; 984 985 fdb = br_fdb_find(br, addr, vlan); 986 if (!fdb || fdb->dst != p) 987 return -ENOENT; 988 989 fdb_delete(br, fdb, true); 990 991 return 0; 992 } 993 994 static int __br_fdb_delete(struct net_bridge *br, 995 const struct net_bridge_port *p, 996 const unsigned char *addr, u16 vid) 997 { 998 int err; 999 1000 spin_lock_bh(&br->hash_lock); 1001 err = fdb_delete_by_addr_and_port(br, p, addr, vid); 1002 spin_unlock_bh(&br->hash_lock); 1003 1004 return err; 1005 } 1006 1007 /* Remove neighbor entry with RTM_DELNEIGH */ 1008 int br_fdb_delete(struct ndmsg *ndm, struct nlattr *tb[], 1009 struct net_device *dev, 1010 const unsigned char *addr, u16 vid) 1011 { 1012 struct net_bridge_vlan_group *vg; 1013 struct net_bridge_port *p = NULL; 1014 struct net_bridge_vlan *v; 1015 struct net_bridge *br; 1016 int err; 1017 1018 if (dev->priv_flags & IFF_EBRIDGE) { 1019 br = netdev_priv(dev); 1020 vg = br_vlan_group(br); 1021 } else { 1022 p = br_port_get_rtnl(dev); 1023 if (!p) { 1024 pr_info("bridge: RTM_DELNEIGH %s not a bridge port\n", 1025 dev->name); 1026 return -EINVAL; 1027 } 1028 vg = nbp_vlan_group(p); 1029 br = p->br; 1030 } 1031 1032 if (vid) { 1033 v = br_vlan_find(vg, vid); 1034 if (!v) { 1035 pr_info("bridge: RTM_DELNEIGH with unconfigured vlan %d on %s\n", vid, dev->name); 1036 return -EINVAL; 1037 } 1038 1039 err = __br_fdb_delete(br, p, addr, vid); 1040 } else { 1041 err = -ENOENT; 1042 err &= __br_fdb_delete(br, p, addr, 0); 1043 if (!vg || !vg->num_vlans) 1044 return err; 1045 1046 list_for_each_entry(v, &vg->vlan_list, vlist) { 1047 if (!br_vlan_should_use(v)) 1048 continue; 1049 err &= __br_fdb_delete(br, p, addr, v->vid); 1050 } 1051 } 1052 1053 return err; 1054 } 1055 1056 int br_fdb_sync_static(struct net_bridge *br, struct net_bridge_port *p) 1057 { 1058 struct net_bridge_fdb_entry *f, *tmp; 1059 int err = 0; 1060 1061 ASSERT_RTNL(); 1062 1063 /* the key here is that static entries change only under rtnl */ 1064 rcu_read_lock(); 1065 hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) { 1066 /* We only care for static entries */ 1067 if (!f->is_static) 1068 continue; 1069 err = dev_uc_add(p->dev, f->key.addr.addr); 1070 if (err) 1071 goto rollback; 1072 } 1073 done: 1074 rcu_read_unlock(); 1075 1076 return err; 1077 1078 rollback: 1079 hlist_for_each_entry_rcu(tmp, &br->fdb_list, fdb_node) { 1080 /* We only care for static entries */ 1081 if (!tmp->is_static) 1082 continue; 1083 if (tmp == f) 1084 break; 1085 dev_uc_del(p->dev, tmp->key.addr.addr); 1086 } 1087 1088 goto done; 1089 } 1090 1091 void br_fdb_unsync_static(struct net_bridge *br, struct net_bridge_port *p) 1092 { 1093 struct net_bridge_fdb_entry *f; 1094 1095 ASSERT_RTNL(); 1096 1097 rcu_read_lock(); 1098 hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) { 1099 /* We only care for static entries */ 1100 if (!f->is_static) 1101 continue; 1102 1103 dev_uc_del(p->dev, f->key.addr.addr); 1104 } 1105 rcu_read_unlock(); 1106 } 1107 1108 int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p, 1109 const unsigned char *addr, u16 vid, 1110 bool swdev_notify) 1111 { 1112 struct net_bridge_fdb_entry *fdb; 1113 bool modified = false; 1114 int err = 0; 1115 1116 trace_br_fdb_external_learn_add(br, p, addr, vid); 1117 1118 spin_lock_bh(&br->hash_lock); 1119 1120 fdb = br_fdb_find(br, addr, vid); 1121 if (!fdb) { 1122 fdb = fdb_create(br, p, addr, vid, 0, 0); 1123 if (!fdb) { 1124 err = -ENOMEM; 1125 goto err_unlock; 1126 } 1127 if (swdev_notify) 1128 fdb->added_by_user = 1; 1129 fdb->added_by_external_learn = 1; 1130 fdb_notify(br, fdb, RTM_NEWNEIGH, swdev_notify); 1131 } else { 1132 fdb->updated = jiffies; 1133 1134 if (fdb->dst != p) { 1135 fdb->dst = p; 1136 modified = true; 1137 } 1138 1139 if (fdb->added_by_external_learn) { 1140 /* Refresh entry */ 1141 fdb->used = jiffies; 1142 } else if (!fdb->added_by_user) { 1143 /* Take over SW learned entry */ 1144 fdb->added_by_external_learn = 1; 1145 modified = true; 1146 } 1147 1148 if (swdev_notify) 1149 fdb->added_by_user = 1; 1150 1151 if (modified) 1152 fdb_notify(br, fdb, RTM_NEWNEIGH, swdev_notify); 1153 } 1154 1155 err_unlock: 1156 spin_unlock_bh(&br->hash_lock); 1157 1158 return err; 1159 } 1160 1161 int br_fdb_external_learn_del(struct net_bridge *br, struct net_bridge_port *p, 1162 const unsigned char *addr, u16 vid, 1163 bool swdev_notify) 1164 { 1165 struct net_bridge_fdb_entry *fdb; 1166 int err = 0; 1167 1168 spin_lock_bh(&br->hash_lock); 1169 1170 fdb = br_fdb_find(br, addr, vid); 1171 if (fdb && fdb->added_by_external_learn) 1172 fdb_delete(br, fdb, swdev_notify); 1173 else 1174 err = -ENOENT; 1175 1176 spin_unlock_bh(&br->hash_lock); 1177 1178 return err; 1179 } 1180 1181 void br_fdb_offloaded_set(struct net_bridge *br, struct net_bridge_port *p, 1182 const unsigned char *addr, u16 vid, bool offloaded) 1183 { 1184 struct net_bridge_fdb_entry *fdb; 1185 1186 spin_lock_bh(&br->hash_lock); 1187 1188 fdb = br_fdb_find(br, addr, vid); 1189 if (fdb) 1190 fdb->offloaded = offloaded; 1191 1192 spin_unlock_bh(&br->hash_lock); 1193 } 1194 1195 void br_fdb_clear_offload(const struct net_device *dev, u16 vid) 1196 { 1197 struct net_bridge_fdb_entry *f; 1198 struct net_bridge_port *p; 1199 1200 ASSERT_RTNL(); 1201 1202 p = br_port_get_rtnl(dev); 1203 if (!p) 1204 return; 1205 1206 spin_lock_bh(&p->br->hash_lock); 1207 hlist_for_each_entry(f, &p->br->fdb_list, fdb_node) { 1208 if (f->dst == p && f->key.vlan_id == vid) 1209 f->offloaded = 0; 1210 } 1211 spin_unlock_bh(&p->br->hash_lock); 1212 } 1213 EXPORT_SYMBOL_GPL(br_fdb_clear_offload); 1214