net/bridge/br_fdb.c

   1 /*
   2  *      Forwarding database
   3  *      Linux ethernet bridge
   4  *
   5  *      Authors:
   6  *      Lennert Buytenhek               <buytenh@gnu.org>
   7  *
   8  *      This program is free software; you can redistribute it and/or
   9  *      modify it under the terms of the GNU General Public License
  10  *      as published by the Free Software Foundation; either version
  11  *      2 of the License, or (at your option) any later version.
  12  */
  13
  14 #include <linux/kernel.h>
  15 #include <linux/init.h>
  16 #include <linux/rculist.h>
  17 #include <linux/spinlock.h>
  18 #include <linux/times.h>
  19 #include <linux/netdevice.h>
  20 #include <linux/etherdevice.h>
  21 #include <linux/jhash.h>
  22 #include <linux/random.h>
  23 #include <linux/slab.h>
  24 #include <linux/atomic.h>
  25 #include <asm/unaligned.h>
  26 #include <linux/if_vlan.h>
  27 #include <net/switchdev.h>
  28 #include <trace/events/bridge.h>
  29 #include "br_private.h"
  30
  31 static const struct rhashtable_params br_fdb_rht_params = {
  32         .head_offset = offsetof(struct net_bridge_fdb_entry, rhnode),
  33         .key_offset = offsetof(struct net_bridge_fdb_entry, key),
  34         .key_len = sizeof(struct net_bridge_fdb_key),
  35         .automatic_shrinking = true,
  36 };
  37
  38 static struct kmem_cache *br_fdb_cache __read_mostly;
  39 static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
  40                       const unsigned char *addr, u16 vid);
  41 static void fdb_notify(struct net_bridge *br,
  42                        const struct net_bridge_fdb_entry *, int, bool);
  43
  44 int __init br_fdb_init(void)
  45 {
  46         br_fdb_cache = kmem_cache_create("bridge_fdb_cache",
  47                                          sizeof(struct net_bridge_fdb_entry),
  48                                          0,
  49                                          SLAB_HWCACHE_ALIGN, NULL);
  50         if (!br_fdb_cache)
  51                 return -ENOMEM;
  52
  53         return 0;
  54 }
  55
  56 void br_fdb_fini(void)
  57 {
  58         kmem_cache_destroy(br_fdb_cache);
  59 }
  60
  61 int br_fdb_hash_init(struct net_bridge *br)
  62 {
  63         return rhashtable_init(&br->fdb_hash_tbl, &br_fdb_rht_params);
  64 }
  65
  66 void br_fdb_hash_fini(struct net_bridge *br)
  67 {
  68         rhashtable_destroy(&br->fdb_hash_tbl);
  69 }
  70
  71 /* if topology_changing then use forward_delay (default 15 sec)
  72  * otherwise keep longer (default 5 minutes)
  73  */
  74 static inline unsigned long hold_time(const struct net_bridge *br)
  75 {
  76         return br->topology_change ? br->forward_delay : br->ageing_time;
  77 }
  78
  79 static inline int has_expired(const struct net_bridge *br,
  80                                   const struct net_bridge_fdb_entry *fdb)
  81 {
  82         return !fdb->is_static && !fdb->added_by_external_learn &&
  83                 time_before_eq(fdb->updated + hold_time(br), jiffies);
  84 }
  85
  86 static void fdb_rcu_free(struct rcu_head *head)
  87 {
  88         struct net_bridge_fdb_entry *ent
  89                 = container_of(head, struct net_bridge_fdb_entry, rcu);
  90         kmem_cache_free(br_fdb_cache, ent);
  91 }
  92
  93 static struct net_bridge_fdb_entry *fdb_find_rcu(struct rhashtable *tbl,
  94                                                  const unsigned char *addr,
  95                                                  __u16 vid)
  96 {
  97         struct net_bridge_fdb_key key;
  98
  99         WARN_ON_ONCE(!rcu_read_lock_held());
 100
 101         key.vlan_id = vid;
 102         memcpy(key.addr.addr, addr, sizeof(key.addr.addr));
 103
 104         return rhashtable_lookup(tbl, &key, br_fdb_rht_params);
 105 }
 106
 107 /* requires bridge hash_lock */
 108 static struct net_bridge_fdb_entry *br_fdb_find(struct net_bridge *br,
 109                                                 const unsigned char *addr,
 110                                                 __u16 vid)
 111 {
 112         struct net_bridge_fdb_entry *fdb;
 113
 114         lockdep_assert_held_once(&br->hash_lock);
 115
 116         rcu_read_lock();
 117         fdb = fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
 118         rcu_read_unlock();
 119
 120         return fdb;
 121 }
 122
 123 struct net_device *br_fdb_find_port(const struct net_device *br_dev,
 124                                     const unsigned char *addr,
 125                                     __u16 vid)
 126 {
 127         struct net_bridge_fdb_entry *f;
 128         struct net_device *dev = NULL;
 129         struct net_bridge *br;
 130
 131         ASSERT_RTNL();
 132
 133         if (!netif_is_bridge_master(br_dev))
 134                 return NULL;
 135
 136         br = netdev_priv(br_dev);
 137         rcu_read_lock();
 138         f = br_fdb_find_rcu(br, addr, vid);
 139         if (f && f->dst)
 140                 dev = f->dst->dev;
 141         rcu_read_unlock();
 142
 143         return dev;
 144 }
 145 EXPORT_SYMBOL_GPL(br_fdb_find_port);
 146
 147 struct net_bridge_fdb_entry *br_fdb_find_rcu(struct net_bridge *br,
 148                                              const unsigned char *addr,
 149                                              __u16 vid)
 150 {
 151         return fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
 152 }
 153
 154 /* When a static FDB entry is added, the mac address from the entry is
 155  * added to the bridge private HW address list and all required ports
 156  * are then updated with the new information.
 157  * Called under RTNL.
 158  */
 159 static void fdb_add_hw_addr(struct net_bridge *br, const unsigned char *addr)
 160 {
 161         int err;
 162         struct net_bridge_port *p;
 163
 164         ASSERT_RTNL();
 165
 166         list_for_each_entry(p, &br->port_list, list) {
 167                 if (!br_promisc_port(p)) {
 168                         err = dev_uc_add(p->dev, addr);
 169                         if (err)
 170                                 goto undo;
 171                 }
 172         }
 173
 174         return;
 175 undo:
 176         list_for_each_entry_continue_reverse(p, &br->port_list, list) {
 177                 if (!br_promisc_port(p))
 178                         dev_uc_del(p->dev, addr);
 179         }
 180 }
 181
 182 /* When a static FDB entry is deleted, the HW address from that entry is
 183  * also removed from the bridge private HW address list and updates all
 184  * the ports with needed information.
 185  * Called under RTNL.
 186  */
 187 static void fdb_del_hw_addr(struct net_bridge *br, const unsigned char *addr)
 188 {
 189         struct net_bridge_port *p;
 190
 191         ASSERT_RTNL();
 192
 193         list_for_each_entry(p, &br->port_list, list) {
 194                 if (!br_promisc_port(p))
 195                         dev_uc_del(p->dev, addr);
 196         }
 197 }
 198
 199 static void fdb_delete(struct net_bridge *br, struct net_bridge_fdb_entry *f,
 200                        bool swdev_notify)
 201 {
 202         trace_fdb_delete(br, f);
 203
 204         if (f->is_static)
 205                 fdb_del_hw_addr(br, f->key.addr.addr);
 206
 207         hlist_del_init_rcu(&f->fdb_node);
 208         rhashtable_remove_fast(&br->fdb_hash_tbl, &f->rhnode,
 209                                br_fdb_rht_params);
 210         fdb_notify(br, f, RTM_DELNEIGH, swdev_notify);
 211         call_rcu(&f->rcu, fdb_rcu_free);
 212 }
 213
 214 /* Delete a local entry if no other port had the same address. */
 215 static void fdb_delete_local(struct net_bridge *br,
 216                              const struct net_bridge_port *p,
 217                              struct net_bridge_fdb_entry *f)
 218 {
 219         const unsigned char *addr = f->key.addr.addr;
 220         struct net_bridge_vlan_group *vg;
 221         const struct net_bridge_vlan *v;
 222         struct net_bridge_port *op;
 223         u16 vid = f->key.vlan_id;
 224
 225         /* Maybe another port has same hw addr? */
 226         list_for_each_entry(op, &br->port_list, list) {
 227                 vg = nbp_vlan_group(op);
 228                 if (op != p && ether_addr_equal(op->dev->dev_addr, addr) &&
 229                     (!vid || br_vlan_find(vg, vid))) {
 230                         f->dst = op;
 231                         f->added_by_user = 0;
 232                         return;
 233                 }
 234         }
 235
 236         vg = br_vlan_group(br);
 237         v = br_vlan_find(vg, vid);
 238         /* Maybe bridge device has same hw addr? */
 239         if (p && ether_addr_equal(br->dev->dev_addr, addr) &&
 240             (!vid || (v && br_vlan_should_use(v)))) {
 241                 f->dst = NULL;
 242                 f->added_by_user = 0;
 243                 return;
 244         }
 245
 246         fdb_delete(br, f, true);
 247 }
 248
 249 void br_fdb_find_delete_local(struct net_bridge *br,
 250                               const struct net_bridge_port *p,
 251                               const unsigned char *addr, u16 vid)
 252 {
 253         struct net_bridge_fdb_entry *f;
 254
 255         spin_lock_bh(&br->hash_lock);
 256         f = br_fdb_find(br, addr, vid);
 257         if (f && f->is_local && !f->added_by_user && f->dst == p)
 258                 fdb_delete_local(br, p, f);
 259         spin_unlock_bh(&br->hash_lock);
 260 }
 261
 262 void br_fdb_changeaddr(struct net_bridge_port *p, const unsigned char *newaddr)
 263 {
 264         struct net_bridge_vlan_group *vg;
 265         struct net_bridge_fdb_entry *f;
 266         struct net_bridge *br = p->br;
 267         struct net_bridge_vlan *v;
 268
 269         spin_lock_bh(&br->hash_lock);
 270         vg = nbp_vlan_group(p);
 271         hlist_for_each_entry(f, &br->fdb_list, fdb_node) {
 272                 if (f->dst == p && f->is_local && !f->added_by_user) {
 273                         /* delete old one */
 274                         fdb_delete_local(br, p, f);
 275
 276                         /* if this port has no vlan information
 277                          * configured, we can safely be done at
 278                          * this point.
 279                          */
 280                         if (!vg || !vg->num_vlans)
 281                                 goto insert;
 282                 }
 283         }
 284
 285 insert:
 286         /* insert new address,  may fail if invalid address or dup. */
 287         fdb_insert(br, p, newaddr, 0);
 288
 289         if (!vg || !vg->num_vlans)
 290                 goto done;
 291
 292         /* Now add entries for every VLAN configured on the port.
 293          * This function runs under RTNL so the bitmap will not change
 294          * from under us.
 295          */
 296         list_for_each_entry(v, &vg->vlan_list, vlist)
 297                 fdb_insert(br, p, newaddr, v->vid);
 298
 299 done:
 300         spin_unlock_bh(&br->hash_lock);
 301 }
 302
 303 void br_fdb_change_mac_address(struct net_bridge *br, const u8 *newaddr)
 304 {
 305         struct net_bridge_vlan_group *vg;
 306         struct net_bridge_fdb_entry *f;
 307         struct net_bridge_vlan *v;
 308
 309         spin_lock_bh(&br->hash_lock);
 310
 311         /* If old entry was unassociated with any port, then delete it. */
 312         f = br_fdb_find(br, br->dev->dev_addr, 0);
 313         if (f && f->is_local && !f->dst && !f->added_by_user)
 314                 fdb_delete_local(br, NULL, f);
 315
 316         fdb_insert(br, NULL, newaddr, 0);
 317         vg = br_vlan_group(br);
 318         if (!vg || !vg->num_vlans)
 319                 goto out;
 320         /* Now remove and add entries for every VLAN configured on the
 321          * bridge.  This function runs under RTNL so the bitmap will not
 322          * change from under us.
 323          */
 324         list_for_each_entry(v, &vg->vlan_list, vlist) {
 325                 if (!br_vlan_should_use(v))
 326                         continue;
 327                 f = br_fdb_find(br, br->dev->dev_addr, v->vid);
 328                 if (f && f->is_local && !f->dst && !f->added_by_user)
 329                         fdb_delete_local(br, NULL, f);
 330                 fdb_insert(br, NULL, newaddr, v->vid);
 331         }
 332 out:
 333         spin_unlock_bh(&br->hash_lock);
 334 }
 335
 336 void br_fdb_cleanup(struct work_struct *work)
 337 {
 338         struct net_bridge *br = container_of(work, struct net_bridge,
 339                                              gc_work.work);
 340         struct net_bridge_fdb_entry *f = NULL;
 341         unsigned long delay = hold_time(br);
 342         unsigned long work_delay = delay;
 343         unsigned long now = jiffies;
 344
 345         /* this part is tricky, in order to avoid blocking learning and
 346          * consequently forwarding, we rely on rcu to delete objects with
 347          * delayed freeing allowing us to continue traversing
 348          */
 349         rcu_read_lock();
 350         hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
 351                 unsigned long this_timer;
 352
 353                 if (f->is_static || f->added_by_external_learn)
 354                         continue;
 355                 this_timer = f->updated + delay;
 356                 if (time_after(this_timer, now)) {
 357                         work_delay = min(work_delay, this_timer - now);
 358                 } else {
 359                         spin_lock_bh(&br->hash_lock);
 360                         if (!hlist_unhashed(&f->fdb_node))
 361                                 fdb_delete(br, f, true);
 362                         spin_unlock_bh(&br->hash_lock);
 363                 }
 364         }
 365         rcu_read_unlock();
 366
 367         /* Cleanup minimum 10 milliseconds apart */
 368         work_delay = max_t(unsigned long, work_delay, msecs_to_jiffies(10));
 369         mod_delayed_work(system_long_wq, &br->gc_work, work_delay);
 370 }
 371
 372 /* Completely flush all dynamic entries in forwarding database.*/
 373 void br_fdb_flush(struct net_bridge *br)
 374 {
 375         struct net_bridge_fdb_entry *f;
 376         struct hlist_node *tmp;
 377
 378         spin_lock_bh(&br->hash_lock);
 379         hlist_for_each_entry_safe(f, tmp, &br->fdb_list, fdb_node) {
 380                 if (!f->is_static)
 381                         fdb_delete(br, f, true);
 382         }
 383         spin_unlock_bh(&br->hash_lock);
 384 }
 385
 386 /* Flush all entries referring to a specific port.
 387  * if do_all is set also flush static entries
 388  * if vid is set delete all entries that match the vlan_id
 389  */
 390 void br_fdb_delete_by_port(struct net_bridge *br,
 391                            const struct net_bridge_port *p,
 392                            u16 vid,
 393                            int do_all)
 394 {
 395         struct net_bridge_fdb_entry *f;
 396         struct hlist_node *tmp;
 397
 398         spin_lock_bh(&br->hash_lock);
 399         hlist_for_each_entry_safe(f, tmp, &br->fdb_list, fdb_node) {
 400                 if (f->dst != p)
 401                         continue;
 402
 403                 if (!do_all)
 404                         if (f->is_static || (vid && f->key.vlan_id != vid))
 405                                 continue;
 406
 407                 if (f->is_local)
 408                         fdb_delete_local(br, p, f);
 409                 else
 410                         fdb_delete(br, f, true);
 411         }
 412         spin_unlock_bh(&br->hash_lock);
 413 }
 414
 415 #if IS_ENABLED(CONFIG_ATM_LANE)
 416 /* Interface used by ATM LANE hook to test
 417  * if an addr is on some other bridge port */
 418 int br_fdb_test_addr(struct net_device *dev, unsigned char *addr)
 419 {
 420         struct net_bridge_fdb_entry *fdb;
 421         struct net_bridge_port *port;
 422         int ret;
 423
 424         rcu_read_lock();
 425         port = br_port_get_rcu(dev);
 426         if (!port)
 427                 ret = 0;
 428         else {
 429                 fdb = br_fdb_find_rcu(port->br, addr, 0);
 430                 ret = fdb && fdb->dst && fdb->dst->dev != dev &&
 431                         fdb->dst->state == BR_STATE_FORWARDING;
 432         }
 433         rcu_read_unlock();
 434
 435         return ret;
 436 }
 437 #endif /* CONFIG_ATM_LANE */
 438
 439 /*
 440  * Fill buffer with forwarding table records in
 441  * the API format.
 442  */
 443 int br_fdb_fillbuf(struct net_bridge *br, void *buf,
 444                    unsigned long maxnum, unsigned long skip)
 445 {
 446         struct net_bridge_fdb_entry *f;
 447         struct __fdb_entry *fe = buf;
 448         int num = 0;
 449
 450         memset(buf, 0, maxnum*sizeof(struct __fdb_entry));
 451
 452         rcu_read_lock();
 453         hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
 454                 if (num >= maxnum)
 455                         break;
 456
 457                 if (has_expired(br, f))
 458                         continue;
 459
 460                 /* ignore pseudo entry for local MAC address */
 461                 if (!f->dst)
 462                         continue;
 463
 464                 if (skip) {
 465                         --skip;
 466                         continue;
 467                 }
 468
 469                 /* convert from internal format to API */
 470                 memcpy(fe->mac_addr, f->key.addr.addr, ETH_ALEN);
 471
 472                 /* due to ABI compat need to split into hi/lo */
 473                 fe->port_no = f->dst->port_no;
 474                 fe->port_hi = f->dst->port_no >> 8;
 475
 476                 fe->is_local = f->is_local;
 477                 if (!f->is_static)
 478                         fe->ageing_timer_value = jiffies_delta_to_clock_t(jiffies - f->updated);
 479                 ++fe;
 480                 ++num;
 481         }
 482         rcu_read_unlock();
 483
 484         return num;
 485 }
 486
 487 static struct net_bridge_fdb_entry *fdb_create(struct net_bridge *br,
 488                                                struct net_bridge_port *source,
 489                                                const unsigned char *addr,
 490                                                __u16 vid,
 491                                                unsigned char is_local,
 492                                                unsigned char is_static)
 493 {
 494         struct net_bridge_fdb_entry *fdb;
 495
 496         fdb = kmem_cache_alloc(br_fdb_cache, GFP_ATOMIC);
 497         if (fdb) {
 498                 memcpy(fdb->key.addr.addr, addr, ETH_ALEN);
 499                 fdb->dst = source;
 500                 fdb->key.vlan_id = vid;
 501                 fdb->is_local = is_local;
 502                 fdb->is_static = is_static;
 503                 fdb->added_by_user = 0;
 504                 fdb->added_by_external_learn = 0;
 505                 fdb->offloaded = 0;
 506                 fdb->is_sticky = 0;
 507                 fdb->updated = fdb->used = jiffies;
 508                 if (rhashtable_lookup_insert_fast(&br->fdb_hash_tbl,
 509                                                   &fdb->rhnode,
 510                                                   br_fdb_rht_params)) {
 511                         kmem_cache_free(br_fdb_cache, fdb);
 512                         fdb = NULL;
 513                 } else {
 514                         hlist_add_head_rcu(&fdb->fdb_node, &br->fdb_list);
 515                 }
 516         }
 517         return fdb;
 518 }
 519
 520 static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
 521                   const unsigned char *addr, u16 vid)
 522 {
 523         struct net_bridge_fdb_entry *fdb;
 524
 525         if (!is_valid_ether_addr(addr))
 526                 return -EINVAL;
 527
 528         fdb = br_fdb_find(br, addr, vid);
 529         if (fdb) {
 530                 /* it is okay to have multiple ports with same
 531                  * address, just use the first one.
 532                  */
 533                 if (fdb->is_local)
 534                         return 0;
 535                 br_warn(br, "adding interface %s with same address as a received packet (addr:%pM, vlan:%u)\n",
 536                        source ? source->dev->name : br->dev->name, addr, vid);
 537                 fdb_delete(br, fdb, true);
 538         }
 539
 540         fdb = fdb_create(br, source, addr, vid, 1, 1);
 541         if (!fdb)
 542                 return -ENOMEM;
 543
 544         fdb_add_hw_addr(br, addr);
 545         fdb_notify(br, fdb, RTM_NEWNEIGH, true);
 546         return 0;
 547 }
 548
 549 /* Add entry for local address of interface */
 550 int br_fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
 551                   const unsigned char *addr, u16 vid)
 552 {
 553         int ret;
 554
 555         spin_lock_bh(&br->hash_lock);
 556         ret = fdb_insert(br, source, addr, vid);
 557         spin_unlock_bh(&br->hash_lock);
 558         return ret;
 559 }
 560
 561 void br_fdb_update(struct net_bridge *br, struct net_bridge_port *source,
 562                    const unsigned char *addr, u16 vid, bool added_by_user)
 563 {
 564         struct net_bridge_fdb_entry *fdb;
 565         bool fdb_modified = false;
 566
 567         /* some users want to always flood. */
 568         if (hold_time(br) == 0)
 569                 return;
 570
 571         /* ignore packets unless we are using this port */
 572         if (!(source->state == BR_STATE_LEARNING ||
 573               source->state == BR_STATE_FORWARDING))
 574                 return;
 575
 576         fdb = fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
 577         if (likely(fdb)) {
 578                 /* attempt to update an entry for a local interface */
 579                 if (unlikely(fdb->is_local)) {
 580                         if (net_ratelimit())
 581                                 br_warn(br, "received packet on %s with own address as source address (addr:%pM, vlan:%u)\n",
 582                                         source->dev->name, addr, vid);
 583                 } else {
 584                         unsigned long now = jiffies;
 585
 586                         /* fastpath: update of existing entry */
 587                         if (unlikely(source != fdb->dst && !fdb->is_sticky)) {
 588                                 fdb->dst = source;
 589                                 fdb_modified = true;
 590                                 /* Take over HW learned entry */
 591                                 if (unlikely(fdb->added_by_external_learn))
 592                                         fdb->added_by_external_learn = 0;
 593                         }
 594                         if (now != fdb->updated)
 595                                 fdb->updated = now;
 596                         if (unlikely(added_by_user))
 597                                 fdb->added_by_user = 1;
 598                         if (unlikely(fdb_modified)) {
 599                                 trace_br_fdb_update(br, source, addr, vid, added_by_user);
 600                                 fdb_notify(br, fdb, RTM_NEWNEIGH, true);
 601                         }
 602                 }
 603         } else {
 604                 spin_lock(&br->hash_lock);
 605                 fdb = fdb_create(br, source, addr, vid, 0, 0);
 606                 if (fdb) {
 607                         if (unlikely(added_by_user))
 608                                 fdb->added_by_user = 1;
 609                         trace_br_fdb_update(br, source, addr, vid,
 610                                             added_by_user);
 611                         fdb_notify(br, fdb, RTM_NEWNEIGH, true);
 612                 }
 613                 /* else  we lose race and someone else inserts
 614                  * it first, don't bother updating
 615                  */
 616                 spin_unlock(&br->hash_lock);
 617         }
 618 }
 619
 620 static int fdb_to_nud(const struct net_bridge *br,
 621                       const struct net_bridge_fdb_entry *fdb)
 622 {
 623         if (fdb->is_local)
 624                 return NUD_PERMANENT;
 625         else if (fdb->is_static)
 626                 return NUD_NOARP;
 627         else if (has_expired(br, fdb))
 628                 return NUD_STALE;
 629         else
 630                 return NUD_REACHABLE;
 631 }
 632
 633 static int fdb_fill_info(struct sk_buff *skb, const struct net_bridge *br,
 634                          const struct net_bridge_fdb_entry *fdb,
 635                          u32 portid, u32 seq, int type, unsigned int flags)
 636 {
 637         unsigned long now = jiffies;
 638         struct nda_cacheinfo ci;
 639         struct nlmsghdr *nlh;
 640         struct ndmsg *ndm;
 641
 642         nlh = nlmsg_put(skb, portid, seq, type, sizeof(*ndm), flags);
 643         if (nlh == NULL)
 644                 return -EMSGSIZE;
 645
 646         ndm = nlmsg_data(nlh);
 647         ndm->ndm_family  = AF_BRIDGE;
 648         ndm->ndm_pad1    = 0;
 649         ndm->ndm_pad2    = 0;
 650         ndm->ndm_flags   = 0;
 651         ndm->ndm_type    = 0;
 652         ndm->ndm_ifindex = fdb->dst ? fdb->dst->dev->ifindex : br->dev->ifindex;
 653         ndm->ndm_state   = fdb_to_nud(br, fdb);
 654
 655         if (fdb->offloaded)
 656                 ndm->ndm_flags |= NTF_OFFLOADED;
 657         if (fdb->added_by_external_learn)
 658                 ndm->ndm_flags |= NTF_EXT_LEARNED;
 659         if (fdb->is_sticky)
 660                 ndm->ndm_flags |= NTF_STICKY;
 661
 662         if (nla_put(skb, NDA_LLADDR, ETH_ALEN, &fdb->key.addr))
 663                 goto nla_put_failure;
 664         if (nla_put_u32(skb, NDA_MASTER, br->dev->ifindex))
 665                 goto nla_put_failure;
 666         ci.ndm_used      = jiffies_to_clock_t(now - fdb->used);
 667         ci.ndm_confirmed = 0;
 668         ci.ndm_updated   = jiffies_to_clock_t(now - fdb->updated);
 669         ci.ndm_refcnt    = 0;
 670         if (nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci))
 671                 goto nla_put_failure;
 672
 673         if (fdb->key.vlan_id && nla_put(skb, NDA_VLAN, sizeof(u16),
 674                                         &fdb->key.vlan_id))
 675                 goto nla_put_failure;
 676
 677         nlmsg_end(skb, nlh);
 678         return 0;
 679
 680 nla_put_failure:
 681         nlmsg_cancel(skb, nlh);
 682         return -EMSGSIZE;
 683 }
 684
 685 static inline size_t fdb_nlmsg_size(void)
 686 {
 687         return NLMSG_ALIGN(sizeof(struct ndmsg))
 688                 + nla_total_size(ETH_ALEN) /* NDA_LLADDR */
 689                 + nla_total_size(sizeof(u32)) /* NDA_MASTER */
 690                 + nla_total_size(sizeof(u16)) /* NDA_VLAN */
 691                 + nla_total_size(sizeof(struct nda_cacheinfo));
 692 }
 693
 694 static void fdb_notify(struct net_bridge *br,
 695                        const struct net_bridge_fdb_entry *fdb, int type,
 696                        bool swdev_notify)
 697 {
 698         struct net *net = dev_net(br->dev);
 699         struct sk_buff *skb;
 700         int err = -ENOBUFS;
 701
 702         if (swdev_notify)
 703                 br_switchdev_fdb_notify(fdb, type);
 704
 705         skb = nlmsg_new(fdb_nlmsg_size(), GFP_ATOMIC);
 706         if (skb == NULL)
 707                 goto errout;
 708
 709         err = fdb_fill_info(skb, br, fdb, 0, 0, type, 0);
 710         if (err < 0) {
 711                 /* -EMSGSIZE implies BUG in fdb_nlmsg_size() */
 712                 WARN_ON(err == -EMSGSIZE);
 713                 kfree_skb(skb);
 714                 goto errout;
 715         }
 716         rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
 717         return;
 718 errout:
 719         rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
 720 }
 721
 722 /* Dump information about entries, in response to GETNEIGH */
 723 int br_fdb_dump(struct sk_buff *skb,
 724                 struct netlink_callback *cb,
 725                 struct net_device *dev,
 726                 struct net_device *filter_dev,
 727                 int *idx)
 728 {
 729         struct net_bridge *br = netdev_priv(dev);
 730         struct net_bridge_fdb_entry *f;
 731         int err = 0;
 732
 733         if (!(dev->priv_flags & IFF_EBRIDGE))
 734                 return err;
 735
 736         if (!filter_dev) {
 737                 err = ndo_dflt_fdb_dump(skb, cb, dev, NULL, idx);
 738                 if (err < 0)
 739                         return err;
 740         }
 741
 742         rcu_read_lock();
 743         hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
 744                 if (*idx < cb->args[2])
 745                         goto skip;
 746                 if (filter_dev && (!f->dst || f->dst->dev != filter_dev)) {
 747                         if (filter_dev != dev)
 748                                 goto skip;
 749                         /* !f->dst is a special case for bridge
 750                          * It means the MAC belongs to the bridge
 751                          * Therefore need a little more filtering
 752                          * we only want to dump the !f->dst case
 753                          */
 754                         if (f->dst)
 755                                 goto skip;
 756                 }
 757                 if (!filter_dev && f->dst)
 758                         goto skip;
 759
 760                 err = fdb_fill_info(skb, br, f,
 761                                     NETLINK_CB(cb->skb).portid,
 762                                     cb->nlh->nlmsg_seq,
 763                                     RTM_NEWNEIGH,
 764                                     NLM_F_MULTI);
 765                 if (err < 0)
 766                         break;
 767 skip:
 768                 *idx += 1;
 769         }
 770         rcu_read_unlock();
 771
 772         return err;
 773 }
 774
 775 int br_fdb_get(struct sk_buff *skb,
 776                struct nlattr *tb[],
 777                struct net_device *dev,
 778                const unsigned char *addr,
 779                u16 vid, u32 portid, u32 seq,
 780                struct netlink_ext_ack *extack)
 781 {
 782         struct net_bridge *br = netdev_priv(dev);
 783         struct net_bridge_fdb_entry *f;
 784         int err = 0;
 785
 786         rcu_read_lock();
 787         f = br_fdb_find_rcu(br, addr, vid);
 788         if (!f) {
 789                 NL_SET_ERR_MSG(extack, "Fdb entry not found");
 790                 err = -ENOENT;
 791                 goto errout;
 792         }
 793
 794         err = fdb_fill_info(skb, br, f, portid, seq,
 795                             RTM_NEWNEIGH, 0);
 796 errout:
 797         rcu_read_unlock();
 798         return err;
 799 }
 800
 801 /* Update (create or replace) forwarding database entry */
 802 static int fdb_add_entry(struct net_bridge *br, struct net_bridge_port *source,
 803                          const u8 *addr, u16 state, u16 flags, u16 vid,
 804                          u8 ndm_flags)
 805 {
 806         u8 is_sticky = !!(ndm_flags & NTF_STICKY);
 807         struct net_bridge_fdb_entry *fdb;
 808         bool modified = false;
 809
 810         /* If the port cannot learn allow only local and static entries */
 811         if (source && !(state & NUD_PERMANENT) && !(state & NUD_NOARP) &&
 812             !(source->state == BR_STATE_LEARNING ||
 813               source->state == BR_STATE_FORWARDING))
 814                 return -EPERM;
 815
 816         if (!source && !(state & NUD_PERMANENT)) {
 817                 pr_info("bridge: RTM_NEWNEIGH %s without NUD_PERMANENT\n",
 818                         br->dev->name);
 819                 return -EINVAL;
 820         }
 821
 822         if (is_sticky && (state & NUD_PERMANENT))
 823                 return -EINVAL;
 824
 825         fdb = br_fdb_find(br, addr, vid);
 826         if (fdb == NULL) {
 827                 if (!(flags & NLM_F_CREATE))
 828                         return -ENOENT;
 829
 830                 fdb = fdb_create(br, source, addr, vid, 0, 0);
 831                 if (!fdb)
 832                         return -ENOMEM;
 833
 834                 modified = true;
 835         } else {
 836                 if (flags & NLM_F_EXCL)
 837                         return -EEXIST;
 838
 839                 if (fdb->dst != source) {
 840                         fdb->dst = source;
 841                         modified = true;
 842                 }
 843         }
 844
 845         if (fdb_to_nud(br, fdb) != state) {
 846                 if (state & NUD_PERMANENT) {
 847                         fdb->is_local = 1;
 848                         if (!fdb->is_static) {
 849                                 fdb->is_static = 1;
 850                                 fdb_add_hw_addr(br, addr);
 851                         }
 852                 } else if (state & NUD_NOARP) {
 853                         fdb->is_local = 0;
 854                         if (!fdb->is_static) {
 855                                 fdb->is_static = 1;
 856                                 fdb_add_hw_addr(br, addr);
 857                         }
 858                 } else {
 859                         fdb->is_local = 0;
 860                         if (fdb->is_static) {
 861                                 fdb->is_static = 0;
 862                                 fdb_del_hw_addr(br, addr);
 863                         }
 864                 }
 865
 866                 modified = true;
 867         }
 868
 869         if (is_sticky != fdb->is_sticky) {
 870                 fdb->is_sticky = is_sticky;
 871                 modified = true;
 872         }
 873
 874         fdb->added_by_user = 1;
 875
 876         fdb->used = jiffies;
 877         if (modified) {
 878                 fdb->updated = jiffies;
 879                 fdb_notify(br, fdb, RTM_NEWNEIGH, true);
 880         }
 881
 882         return 0;
 883 }
 884
 885 static int __br_fdb_add(struct ndmsg *ndm, struct net_bridge *br,
 886                         struct net_bridge_port *p, const unsigned char *addr,
 887                         u16 nlh_flags, u16 vid)
 888 {
 889         int err = 0;
 890
 891         if (ndm->ndm_flags & NTF_USE) {
 892                 if (!p) {
 893                         pr_info("bridge: RTM_NEWNEIGH %s with NTF_USE is not supported\n",
 894                                 br->dev->name);
 895                         return -EINVAL;
 896                 }
 897                 local_bh_disable();
 898                 rcu_read_lock();
 899                 br_fdb_update(br, p, addr, vid, true);
 900                 rcu_read_unlock();
 901                 local_bh_enable();
 902         } else if (ndm->ndm_flags & NTF_EXT_LEARNED) {
 903                 err = br_fdb_external_learn_add(br, p, addr, vid, true);
 904         } else {
 905                 spin_lock_bh(&br->hash_lock);
 906                 err = fdb_add_entry(br, p, addr, ndm->ndm_state,
 907                                     nlh_flags, vid, ndm->ndm_flags);
 908                 spin_unlock_bh(&br->hash_lock);
 909         }
 910
 911         return err;
 912 }
 913
 914 /* Add new permanent fdb entry with RTM_NEWNEIGH */
 915 int br_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
 916                struct net_device *dev,
 917                const unsigned char *addr, u16 vid, u16 nlh_flags,
 918                struct netlink_ext_ack *extack)
 919 {
 920         struct net_bridge_vlan_group *vg;
 921         struct net_bridge_port *p = NULL;
 922         struct net_bridge_vlan *v;
 923         struct net_bridge *br = NULL;
 924         int err = 0;
 925
 926         trace_br_fdb_add(ndm, dev, addr, vid, nlh_flags);
 927
 928         if (!(ndm->ndm_state & (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE))) {
 929                 pr_info("bridge: RTM_NEWNEIGH with invalid state %#x\n", ndm->ndm_state);
 930                 return -EINVAL;
 931         }
 932
 933         if (is_zero_ether_addr(addr)) {
 934                 pr_info("bridge: RTM_NEWNEIGH with invalid ether address\n");
 935                 return -EINVAL;
 936         }
 937
 938         if (dev->priv_flags & IFF_EBRIDGE) {
 939                 br = netdev_priv(dev);
 940                 vg = br_vlan_group(br);
 941         } else {
 942                 p = br_port_get_rtnl(dev);
 943                 if (!p) {
 944                         pr_info("bridge: RTM_NEWNEIGH %s not a bridge port\n",
 945                                 dev->name);
 946                         return -EINVAL;
 947                 }
 948                 br = p->br;
 949                 vg = nbp_vlan_group(p);
 950         }
 951
 952         if (vid) {
 953                 v = br_vlan_find(vg, vid);
 954                 if (!v || !br_vlan_should_use(v)) {
 955                         pr_info("bridge: RTM_NEWNEIGH with unconfigured vlan %d on %s\n", vid, dev->name);
 956                         return -EINVAL;
 957                 }
 958
 959                 /* VID was specified, so use it. */
 960                 err = __br_fdb_add(ndm, br, p, addr, nlh_flags, vid);
 961         } else {
 962                 err = __br_fdb_add(ndm, br, p, addr, nlh_flags, 0);
 963                 if (err || !vg || !vg->num_vlans)
 964                         goto out;
 965
 966                 /* We have vlans configured on this port and user didn't
 967                  * specify a VLAN.  To be nice, add/update entry for every
 968                  * vlan on this port.
 969                  */
 970                 list_for_each_entry(v, &vg->vlan_list, vlist) {
 971                         if (!br_vlan_should_use(v))
 972                                 continue;
 973                         err = __br_fdb_add(ndm, br, p, addr, nlh_flags, v->vid);
 974                         if (err)
 975                                 goto out;
 976                 }
 977         }
 978
 979 out:
 980         return err;
 981 }
 982
 983 static int fdb_delete_by_addr_and_port(struct net_bridge *br,
 984                                        const struct net_bridge_port *p,
 985                                        const u8 *addr, u16 vlan)
 986 {
 987         struct net_bridge_fdb_entry *fdb;
 988
 989         fdb = br_fdb_find(br, addr, vlan);
 990         if (!fdb || fdb->dst != p)
 991                 return -ENOENT;
 992
 993         fdb_delete(br, fdb, true);
 994
 995         return 0;
 996 }
 997
 998 static int __br_fdb_delete(struct net_bridge *br,
 999                            const struct net_bridge_port *p,
1000                            const unsigned char *addr, u16 vid)
1001 {
1002         int err;
1003
1004         spin_lock_bh(&br->hash_lock);
1005         err = fdb_delete_by_addr_and_port(br, p, addr, vid);
1006         spin_unlock_bh(&br->hash_lock);
1007
1008         return err;
1009 }
1010
1011 /* Remove neighbor entry with RTM_DELNEIGH */
1012 int br_fdb_delete(struct ndmsg *ndm, struct nlattr *tb[],
1013                   struct net_device *dev,
1014                   const unsigned char *addr, u16 vid)
1015 {
1016         struct net_bridge_vlan_group *vg;
1017         struct net_bridge_port *p = NULL;
1018         struct net_bridge_vlan *v;
1019         struct net_bridge *br;
1020         int err;
1021
1022         if (dev->priv_flags & IFF_EBRIDGE) {
1023                 br = netdev_priv(dev);
1024                 vg = br_vlan_group(br);
1025         } else {
1026                 p = br_port_get_rtnl(dev);
1027                 if (!p) {
1028                         pr_info("bridge: RTM_DELNEIGH %s not a bridge port\n",
1029                                 dev->name);
1030                         return -EINVAL;
1031                 }
1032                 vg = nbp_vlan_group(p);
1033                 br = p->br;
1034         }
1035
1036         if (vid) {
1037                 v = br_vlan_find(vg, vid);
1038                 if (!v) {
1039                         pr_info("bridge: RTM_DELNEIGH with unconfigured vlan %d on %s\n", vid, dev->name);
1040                         return -EINVAL;
1041                 }
1042
1043                 err = __br_fdb_delete(br, p, addr, vid);
1044         } else {
1045                 err = -ENOENT;
1046                 err &= __br_fdb_delete(br, p, addr, 0);
1047                 if (!vg || !vg->num_vlans)
1048                         return err;
1049
1050                 list_for_each_entry(v, &vg->vlan_list, vlist) {
1051                         if (!br_vlan_should_use(v))
1052                                 continue;
1053                         err &= __br_fdb_delete(br, p, addr, v->vid);
1054                 }
1055         }
1056
1057         return err;
1058 }
1059
1060 int br_fdb_sync_static(struct net_bridge *br, struct net_bridge_port *p)
1061 {
1062         struct net_bridge_fdb_entry *f, *tmp;
1063         int err = 0;
1064
1065         ASSERT_RTNL();
1066
1067         /* the key here is that static entries change only under rtnl */
1068         rcu_read_lock();
1069         hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
1070                 /* We only care for static entries */
1071                 if (!f->is_static)
1072                         continue;
1073                 err = dev_uc_add(p->dev, f->key.addr.addr);
1074                 if (err)
1075                         goto rollback;
1076         }
1077 done:
1078         rcu_read_unlock();
1079
1080         return err;
1081
1082 rollback:
1083         hlist_for_each_entry_rcu(tmp, &br->fdb_list, fdb_node) {
1084                 /* We only care for static entries */
1085                 if (!tmp->is_static)
1086                         continue;
1087                 if (tmp == f)
1088                         break;
1089                 dev_uc_del(p->dev, tmp->key.addr.addr);
1090         }
1091
1092         goto done;
1093 }
1094
1095 void br_fdb_unsync_static(struct net_bridge *br, struct net_bridge_port *p)
1096 {
1097         struct net_bridge_fdb_entry *f;
1098
1099         ASSERT_RTNL();
1100
1101         rcu_read_lock();
1102         hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
1103                 /* We only care for static entries */
1104                 if (!f->is_static)
1105                         continue;
1106
1107                 dev_uc_del(p->dev, f->key.addr.addr);
1108         }
1109         rcu_read_unlock();
1110 }
1111
1112 int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p,
1113                               const unsigned char *addr, u16 vid,
1114                               bool swdev_notify)
1115 {
1116         struct net_bridge_fdb_entry *fdb;
1117         bool modified = false;
1118         int err = 0;
1119
1120         trace_br_fdb_external_learn_add(br, p, addr, vid);
1121
1122         spin_lock_bh(&br->hash_lock);
1123
1124         fdb = br_fdb_find(br, addr, vid);
1125         if (!fdb) {
1126                 fdb = fdb_create(br, p, addr, vid, 0, 0);
1127                 if (!fdb) {
1128                         err = -ENOMEM;
1129                         goto err_unlock;
1130                 }
1131                 if (swdev_notify)
1132                         fdb->added_by_user = 1;
1133                 fdb->added_by_external_learn = 1;
1134                 fdb_notify(br, fdb, RTM_NEWNEIGH, swdev_notify);
1135         } else {
1136                 fdb->updated = jiffies;
1137
1138                 if (fdb->dst != p) {
1139                         fdb->dst = p;
1140                         modified = true;
1141                 }
1142
1143                 if (fdb->added_by_external_learn) {
1144                         /* Refresh entry */
1145                         fdb->used = jiffies;
1146                 } else if (!fdb->added_by_user) {
1147                         /* Take over SW learned entry */
1148                         fdb->added_by_external_learn = 1;
1149                         modified = true;
1150                 }
1151
1152                 if (swdev_notify)
1153                         fdb->added_by_user = 1;
1154
1155                 if (modified)
1156                         fdb_notify(br, fdb, RTM_NEWNEIGH, swdev_notify);
1157         }
1158
1159 err_unlock:
1160         spin_unlock_bh(&br->hash_lock);
1161
1162         return err;
1163 }
1164
1165 int br_fdb_external_learn_del(struct net_bridge *br, struct net_bridge_port *p,
1166                               const unsigned char *addr, u16 vid,
1167                               bool swdev_notify)
1168 {
1169         struct net_bridge_fdb_entry *fdb;
1170         int err = 0;
1171
1172         spin_lock_bh(&br->hash_lock);
1173
1174         fdb = br_fdb_find(br, addr, vid);
1175         if (fdb && fdb->added_by_external_learn)
1176                 fdb_delete(br, fdb, swdev_notify);
1177         else
1178                 err = -ENOENT;
1179
1180         spin_unlock_bh(&br->hash_lock);
1181
1182         return err;
1183 }
1184
1185 void br_fdb_offloaded_set(struct net_bridge *br, struct net_bridge_port *p,
1186                           const unsigned char *addr, u16 vid, bool offloaded)
1187 {
1188         struct net_bridge_fdb_entry *fdb;
1189
1190         spin_lock_bh(&br->hash_lock);
1191
1192         fdb = br_fdb_find(br, addr, vid);
1193         if (fdb)
1194                 fdb->offloaded = offloaded;
1195
1196         spin_unlock_bh(&br->hash_lock);
1197 }
1198
1199 void br_fdb_clear_offload(const struct net_device *dev, u16 vid)
1200 {
1201         struct net_bridge_fdb_entry *f;
1202         struct net_bridge_port *p;
1203
1204         ASSERT_RTNL();
1205
1206         p = br_port_get_rtnl(dev);
1207         if (!p)
1208                 return;
1209
1210         spin_lock_bh(&p->br->hash_lock);
1211         hlist_for_each_entry(f, &p->br->fdb_list, fdb_node) {
1212                 if (f->dst == p && f->key.vlan_id == vid)
1213                         f->offloaded = 0;
1214         }
1215         spin_unlock_bh(&p->br->hash_lock);
1216 }
1217 EXPORT_SYMBOL_GPL(br_fdb_clear_offload);