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 "br_private.h"
  29
  30 static struct kmem_cache *br_fdb_cache __read_mostly;
  31 static struct net_bridge_fdb_entry *fdb_find(struct hlist_head *head,
  32                                              const unsigned char *addr,
  33                                              __u16 vid);
  34 static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
  35                       const unsigned char *addr, u16 vid);
  36 static void fdb_notify(struct net_bridge *br,
  37                        const struct net_bridge_fdb_entry *, int);
  38
  39 static u32 fdb_salt __read_mostly;
  40
  41 int __init br_fdb_init(void)
  42 {
  43         br_fdb_cache = kmem_cache_create("bridge_fdb_cache",
  44                                          sizeof(struct net_bridge_fdb_entry),
  45                                          0,
  46                                          SLAB_HWCACHE_ALIGN, NULL);
  47         if (!br_fdb_cache)
  48                 return -ENOMEM;
  49
  50         get_random_bytes(&fdb_salt, sizeof(fdb_salt));
  51         return 0;
  52 }
  53
  54 void br_fdb_fini(void)
  55 {
  56         kmem_cache_destroy(br_fdb_cache);
  57 }
  58
  59
  60 /* if topology_changing then use forward_delay (default 15 sec)
  61  * otherwise keep longer (default 5 minutes)
  62  */
  63 static inline unsigned long hold_time(const struct net_bridge *br)
  64 {
  65         return br->topology_change ? br->forward_delay : br->ageing_time;
  66 }
  67
  68 static inline int has_expired(const struct net_bridge *br,
  69                                   const struct net_bridge_fdb_entry *fdb)
  70 {
  71         return !fdb->is_static &&
  72                 time_before_eq(fdb->updated + hold_time(br), jiffies);
  73 }
  74
  75 static inline int br_mac_hash(const unsigned char *mac, __u16 vid)
  76 {
  77         /* use 1 byte of OUI and 3 bytes of NIC */
  78         u32 key = get_unaligned((u32 *)(mac + 2));
  79         return jhash_2words(key, vid, fdb_salt) & (BR_HASH_SIZE - 1);
  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 /* When a static FDB entry is added, the mac address from the entry is
  90  * added to the bridge private HW address list and all required ports
  91  * are then updated with the new information.
  92  * Called under RTNL.
  93  */
  94 static void fdb_add_hw_addr(struct net_bridge *br, const unsigned char *addr)
  95 {
  96         int err;
  97         struct net_bridge_port *p;
  98
  99         ASSERT_RTNL();
 100
 101         list_for_each_entry(p, &br->port_list, list) {
 102                 if (!br_promisc_port(p)) {
 103                         err = dev_uc_add(p->dev, addr);
 104                         if (err)
 105                                 goto undo;
 106                 }
 107         }
 108
 109         return;
 110 undo:
 111         list_for_each_entry_continue_reverse(p, &br->port_list, list) {
 112                 if (!br_promisc_port(p))
 113                         dev_uc_del(p->dev, addr);
 114         }
 115 }
 116
 117 /* When a static FDB entry is deleted, the HW address from that entry is
 118  * also removed from the bridge private HW address list and updates all
 119  * the ports with needed information.
 120  * Called under RTNL.
 121  */
 122 static void fdb_del_hw_addr(struct net_bridge *br, const unsigned char *addr)
 123 {
 124         struct net_bridge_port *p;
 125
 126         ASSERT_RTNL();
 127
 128         list_for_each_entry(p, &br->port_list, list) {
 129                 if (!br_promisc_port(p))
 130                         dev_uc_del(p->dev, addr);
 131         }
 132 }
 133
 134 static void fdb_del_external_learn(struct net_bridge_fdb_entry *f)
 135 {
 136         struct switchdev_obj obj = {
 137                 .id = SWITCHDEV_OBJ_PORT_FDB,
 138                 .u.fdb = {
 139                         .addr = f->addr.addr,
 140                         .vid = f->vlan_id,
 141                 },
 142         };
 143
 144         switchdev_port_obj_del(f->dst->dev, &obj);
 145 }
 146
 147 static void fdb_delete(struct net_bridge *br, struct net_bridge_fdb_entry *f)
 148 {
 149         if (f->is_static)
 150                 fdb_del_hw_addr(br, f->addr.addr);
 151
 152         if (f->added_by_external_learn)
 153                 fdb_del_external_learn(f);
 154
 155         hlist_del_rcu(&f->hlist);
 156         fdb_notify(br, f, RTM_DELNEIGH);
 157         call_rcu(&f->rcu, fdb_rcu_free);
 158 }
 159
 160 /* Delete a local entry if no other port had the same address. */
 161 static void fdb_delete_local(struct net_bridge *br,
 162                              const struct net_bridge_port *p,
 163                              struct net_bridge_fdb_entry *f)
 164 {
 165         const unsigned char *addr = f->addr.addr;
 166         struct net_bridge_vlan_group *vg;
 167         const struct net_bridge_vlan *v;
 168         struct net_bridge_port *op;
 169         u16 vid = f->vlan_id;
 170
 171         /* Maybe another port has same hw addr? */
 172         list_for_each_entry(op, &br->port_list, list) {
 173                 vg = nbp_vlan_group(op);
 174                 if (op != p && ether_addr_equal(op->dev->dev_addr, addr) &&
 175                     (!vid || br_vlan_find(vg, vid))) {
 176                         f->dst = op;
 177                         f->added_by_user = 0;
 178                         return;
 179                 }
 180         }
 181
 182         vg = br_vlan_group(br);
 183         v = br_vlan_find(vg, vid);
 184         /* Maybe bridge device has same hw addr? */
 185         if (p && ether_addr_equal(br->dev->dev_addr, addr) &&
 186             (!vid || (v && br_vlan_should_use(v)))) {
 187                 f->dst = NULL;
 188                 f->added_by_user = 0;
 189                 return;
 190         }
 191
 192         fdb_delete(br, f);
 193 }
 194
 195 void br_fdb_find_delete_local(struct net_bridge *br,
 196                               const struct net_bridge_port *p,
 197                               const unsigned char *addr, u16 vid)
 198 {
 199         struct hlist_head *head = &br->hash[br_mac_hash(addr, vid)];
 200         struct net_bridge_fdb_entry *f;
 201
 202         spin_lock_bh(&br->hash_lock);
 203         f = fdb_find(head, addr, vid);
 204         if (f && f->is_local && !f->added_by_user && f->dst == p)
 205                 fdb_delete_local(br, p, f);
 206         spin_unlock_bh(&br->hash_lock);
 207 }
 208
 209 void br_fdb_changeaddr(struct net_bridge_port *p, const unsigned char *newaddr)
 210 {
 211         struct net_bridge_vlan_group *vg;
 212         struct net_bridge *br = p->br;
 213         struct net_bridge_vlan *v;
 214         int i;
 215
 216         spin_lock_bh(&br->hash_lock);
 217
 218         vg = nbp_vlan_group(p);
 219         /* Search all chains since old address/hash is unknown */
 220         for (i = 0; i < BR_HASH_SIZE; i++) {
 221                 struct hlist_node *h;
 222                 hlist_for_each(h, &br->hash[i]) {
 223                         struct net_bridge_fdb_entry *f;
 224
 225                         f = hlist_entry(h, struct net_bridge_fdb_entry, hlist);
 226                         if (f->dst == p && f->is_local && !f->added_by_user) {
 227                                 /* delete old one */
 228                                 fdb_delete_local(br, p, f);
 229
 230                                 /* if this port has no vlan information
 231                                  * configured, we can safely be done at
 232                                  * this point.
 233                                  */
 234                                 if (!vg || !vg->num_vlans)
 235                                         goto insert;
 236                         }
 237                 }
 238         }
 239
 240 insert:
 241         /* insert new address,  may fail if invalid address or dup. */
 242         fdb_insert(br, p, newaddr, 0);
 243
 244         if (!vg || !vg->num_vlans)
 245                 goto done;
 246
 247         /* Now add entries for every VLAN configured on the port.
 248          * This function runs under RTNL so the bitmap will not change
 249          * from under us.
 250          */
 251         list_for_each_entry(v, &vg->vlan_list, vlist)
 252                 fdb_insert(br, p, newaddr, v->vid);
 253
 254 done:
 255         spin_unlock_bh(&br->hash_lock);
 256 }
 257
 258 void br_fdb_change_mac_address(struct net_bridge *br, const u8 *newaddr)
 259 {
 260         struct net_bridge_vlan_group *vg;
 261         struct net_bridge_fdb_entry *f;
 262         struct net_bridge_vlan *v;
 263
 264         spin_lock_bh(&br->hash_lock);
 265
 266         /* If old entry was unassociated with any port, then delete it. */
 267         f = __br_fdb_get(br, br->dev->dev_addr, 0);
 268         if (f && f->is_local && !f->dst)
 269                 fdb_delete_local(br, NULL, f);
 270
 271         fdb_insert(br, NULL, newaddr, 0);
 272         vg = br_vlan_group(br);
 273         if (!vg || !vg->num_vlans)
 274                 goto out;
 275         /* Now remove and add entries for every VLAN configured on the
 276          * bridge.  This function runs under RTNL so the bitmap will not
 277          * change from under us.
 278          */
 279         list_for_each_entry(v, &vg->vlan_list, vlist) {
 280                 f = __br_fdb_get(br, br->dev->dev_addr, v->vid);
 281                 if (f && f->is_local && !f->dst)
 282                         fdb_delete_local(br, NULL, f);
 283                 fdb_insert(br, NULL, newaddr, v->vid);
 284         }
 285 out:
 286         spin_unlock_bh(&br->hash_lock);
 287 }
 288
 289 void br_fdb_cleanup(unsigned long _data)
 290 {
 291         struct net_bridge *br = (struct net_bridge *)_data;
 292         unsigned long delay = hold_time(br);
 293         unsigned long next_timer = jiffies + br->ageing_time;
 294         int i;
 295
 296         spin_lock(&br->hash_lock);
 297         for (i = 0; i < BR_HASH_SIZE; i++) {
 298                 struct net_bridge_fdb_entry *f;
 299                 struct hlist_node *n;
 300
 301                 hlist_for_each_entry_safe(f, n, &br->hash[i], hlist) {
 302                         unsigned long this_timer;
 303                         if (f->is_static)
 304                                 continue;
 305                         if (f->added_by_external_learn)
 306                                 continue;
 307                         this_timer = f->updated + delay;
 308                         if (time_before_eq(this_timer, jiffies))
 309                                 fdb_delete(br, f);
 310                         else if (time_before(this_timer, next_timer))
 311                                 next_timer = this_timer;
 312                 }
 313         }
 314         spin_unlock(&br->hash_lock);
 315
 316         mod_timer(&br->gc_timer, round_jiffies_up(next_timer));
 317 }
 318
 319 /* Completely flush all dynamic entries in forwarding database.*/
 320 void br_fdb_flush(struct net_bridge *br)
 321 {
 322         int i;
 323
 324         spin_lock_bh(&br->hash_lock);
 325         for (i = 0; i < BR_HASH_SIZE; i++) {
 326                 struct net_bridge_fdb_entry *f;
 327                 struct hlist_node *n;
 328                 hlist_for_each_entry_safe(f, n, &br->hash[i], hlist) {
 329                         if (!f->is_static)
 330                                 fdb_delete(br, f);
 331                 }
 332         }
 333         spin_unlock_bh(&br->hash_lock);
 334 }
 335
 336 /* Flush all entries referring to a specific port.
 337  * if do_all is set also flush static entries
 338  * if vid is set delete all entries that match the vlan_id
 339  */
 340 void br_fdb_delete_by_port(struct net_bridge *br,
 341                            const struct net_bridge_port *p,
 342                            u16 vid,
 343                            int do_all)
 344 {
 345         int i;
 346
 347         spin_lock_bh(&br->hash_lock);
 348         for (i = 0; i < BR_HASH_SIZE; i++) {
 349                 struct hlist_node *h, *g;
 350
 351                 hlist_for_each_safe(h, g, &br->hash[i]) {
 352                         struct net_bridge_fdb_entry *f
 353                                 = hlist_entry(h, struct net_bridge_fdb_entry, hlist);
 354                         if (f->dst != p)
 355                                 continue;
 356
 357                         if (!do_all)
 358                                 if (f->is_static || (vid && f->vlan_id != vid))
 359                                         continue;
 360
 361                         if (f->is_local)
 362                                 fdb_delete_local(br, p, f);
 363                         else
 364                                 fdb_delete(br, f);
 365                 }
 366         }
 367         spin_unlock_bh(&br->hash_lock);
 368 }
 369
 370 /* No locking or refcounting, assumes caller has rcu_read_lock */
 371 struct net_bridge_fdb_entry *__br_fdb_get(struct net_bridge *br,
 372                                           const unsigned char *addr,
 373                                           __u16 vid)
 374 {
 375         struct net_bridge_fdb_entry *fdb;
 376
 377         hlist_for_each_entry_rcu(fdb,
 378                                 &br->hash[br_mac_hash(addr, vid)], hlist) {
 379                 if (ether_addr_equal(fdb->addr.addr, addr) &&
 380                     fdb->vlan_id == vid) {
 381                         if (unlikely(has_expired(br, fdb)))
 382                                 break;
 383                         return fdb;
 384                 }
 385         }
 386
 387         return NULL;
 388 }
 389
 390 #if IS_ENABLED(CONFIG_ATM_LANE)
 391 /* Interface used by ATM LANE hook to test
 392  * if an addr is on some other bridge port */
 393 int br_fdb_test_addr(struct net_device *dev, unsigned char *addr)
 394 {
 395         struct net_bridge_fdb_entry *fdb;
 396         struct net_bridge_port *port;
 397         int ret;
 398
 399         rcu_read_lock();
 400         port = br_port_get_rcu(dev);
 401         if (!port)
 402                 ret = 0;
 403         else {
 404                 fdb = __br_fdb_get(port->br, addr, 0);
 405                 ret = fdb && fdb->dst && fdb->dst->dev != dev &&
 406                         fdb->dst->state == BR_STATE_FORWARDING;
 407         }
 408         rcu_read_unlock();
 409
 410         return ret;
 411 }
 412 #endif /* CONFIG_ATM_LANE */
 413
 414 /*
 415  * Fill buffer with forwarding table records in
 416  * the API format.
 417  */
 418 int br_fdb_fillbuf(struct net_bridge *br, void *buf,
 419                    unsigned long maxnum, unsigned long skip)
 420 {
 421         struct __fdb_entry *fe = buf;
 422         int i, num = 0;
 423         struct net_bridge_fdb_entry *f;
 424
 425         memset(buf, 0, maxnum*sizeof(struct __fdb_entry));
 426
 427         rcu_read_lock();
 428         for (i = 0; i < BR_HASH_SIZE; i++) {
 429                 hlist_for_each_entry_rcu(f, &br->hash[i], hlist) {
 430                         if (num >= maxnum)
 431                                 goto out;
 432
 433                         if (has_expired(br, f))
 434                                 continue;
 435
 436                         /* ignore pseudo entry for local MAC address */
 437                         if (!f->dst)
 438                                 continue;
 439
 440                         if (skip) {
 441                                 --skip;
 442                                 continue;
 443                         }
 444
 445                         /* convert from internal format to API */
 446                         memcpy(fe->mac_addr, f->addr.addr, ETH_ALEN);
 447
 448                         /* due to ABI compat need to split into hi/lo */
 449                         fe->port_no = f->dst->port_no;
 450                         fe->port_hi = f->dst->port_no >> 8;
 451
 452                         fe->is_local = f->is_local;
 453                         if (!f->is_static)
 454                                 fe->ageing_timer_value = jiffies_delta_to_clock_t(jiffies - f->updated);
 455                         ++fe;
 456                         ++num;
 457                 }
 458         }
 459
 460  out:
 461         rcu_read_unlock();
 462
 463         return num;
 464 }
 465
 466 static struct net_bridge_fdb_entry *fdb_find(struct hlist_head *head,
 467                                              const unsigned char *addr,
 468                                              __u16 vid)
 469 {
 470         struct net_bridge_fdb_entry *fdb;
 471
 472         hlist_for_each_entry(fdb, head, hlist) {
 473                 if (ether_addr_equal(fdb->addr.addr, addr) &&
 474                     fdb->vlan_id == vid)
 475                         return fdb;
 476         }
 477         return NULL;
 478 }
 479
 480 static struct net_bridge_fdb_entry *fdb_find_rcu(struct hlist_head *head,
 481                                                  const unsigned char *addr,
 482                                                  __u16 vid)
 483 {
 484         struct net_bridge_fdb_entry *fdb;
 485
 486         hlist_for_each_entry_rcu(fdb, head, hlist) {
 487                 if (ether_addr_equal(fdb->addr.addr, addr) &&
 488                     fdb->vlan_id == vid)
 489                         return fdb;
 490         }
 491         return NULL;
 492 }
 493
 494 static struct net_bridge_fdb_entry *fdb_create(struct hlist_head *head,
 495                                                struct net_bridge_port *source,
 496                                                const unsigned char *addr,
 497                                                __u16 vid)
 498 {
 499         struct net_bridge_fdb_entry *fdb;
 500
 501         fdb = kmem_cache_alloc(br_fdb_cache, GFP_ATOMIC);
 502         if (fdb) {
 503                 memcpy(fdb->addr.addr, addr, ETH_ALEN);
 504                 fdb->dst = source;
 505                 fdb->vlan_id = vid;
 506                 fdb->is_local = 0;
 507                 fdb->is_static = 0;
 508                 fdb->added_by_user = 0;
 509                 fdb->added_by_external_learn = 0;
 510                 fdb->updated = fdb->used = jiffies;
 511                 hlist_add_head_rcu(&fdb->hlist, head);
 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 hlist_head *head = &br->hash[br_mac_hash(addr, vid)];
 520         struct net_bridge_fdb_entry *fdb;
 521
 522         if (!is_valid_ether_addr(addr))
 523                 return -EINVAL;
 524
 525         fdb = fdb_find(head, addr, vid);
 526         if (fdb) {
 527                 /* it is okay to have multiple ports with same
 528                  * address, just use the first one.
 529                  */
 530                 if (fdb->is_local)
 531                         return 0;
 532                 br_warn(br, "adding interface %s with same address "
 533                        "as a received packet\n",
 534                        source ? source->dev->name : br->dev->name);
 535                 fdb_delete(br, fdb);
 536         }
 537
 538         fdb = fdb_create(head, source, addr, vid);
 539         if (!fdb)
 540                 return -ENOMEM;
 541
 542         fdb->is_local = fdb->is_static = 1;
 543         fdb_add_hw_addr(br, addr);
 544         fdb_notify(br, fdb, RTM_NEWNEIGH);
 545         return 0;
 546 }
 547
 548 /* Add entry for local address of interface */
 549 int br_fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
 550                   const unsigned char *addr, u16 vid)
 551 {
 552         int ret;
 553
 554         spin_lock_bh(&br->hash_lock);
 555         ret = fdb_insert(br, source, addr, vid);
 556         spin_unlock_bh(&br->hash_lock);
 557         return ret;
 558 }
 559
 560 void br_fdb_update(struct net_bridge *br, struct net_bridge_port *source,
 561                    const unsigned char *addr, u16 vid, bool added_by_user)
 562 {
 563         struct hlist_head *head = &br->hash[br_mac_hash(addr, vid)];
 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(head, 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 "
 582                                         "own address as source address\n",
 583                                         source->dev->name);
 584                 } else {
 585                         /* fastpath: update of existing entry */
 586                         if (unlikely(source != fdb->dst)) {
 587                                 fdb->dst = source;
 588                                 fdb_modified = true;
 589                         }
 590                         fdb->updated = jiffies;
 591                         if (unlikely(added_by_user))
 592                                 fdb->added_by_user = 1;
 593                         if (unlikely(fdb_modified))
 594                                 fdb_notify(br, fdb, RTM_NEWNEIGH);
 595                 }
 596         } else {
 597                 spin_lock(&br->hash_lock);
 598                 if (likely(!fdb_find(head, addr, vid))) {
 599                         fdb = fdb_create(head, source, addr, vid);
 600                         if (fdb) {
 601                                 if (unlikely(added_by_user))
 602                                         fdb->added_by_user = 1;
 603                                 fdb_notify(br, fdb, RTM_NEWNEIGH);
 604                         }
 605                 }
 606                 /* else  we lose race and someone else inserts
 607                  * it first, don't bother updating
 608                  */
 609                 spin_unlock(&br->hash_lock);
 610         }
 611 }
 612
 613 static int fdb_to_nud(const struct net_bridge_fdb_entry *fdb)
 614 {
 615         if (fdb->is_local)
 616                 return NUD_PERMANENT;
 617         else if (fdb->is_static)
 618                 return NUD_NOARP;
 619         else if (has_expired(fdb->dst->br, fdb))
 620                 return NUD_STALE;
 621         else
 622                 return NUD_REACHABLE;
 623 }
 624
 625 static int fdb_fill_info(struct sk_buff *skb, const struct net_bridge *br,
 626                          const struct net_bridge_fdb_entry *fdb,
 627                          u32 portid, u32 seq, int type, unsigned int flags)
 628 {
 629         unsigned long now = jiffies;
 630         struct nda_cacheinfo ci;
 631         struct nlmsghdr *nlh;
 632         struct ndmsg *ndm;
 633
 634         nlh = nlmsg_put(skb, portid, seq, type, sizeof(*ndm), flags);
 635         if (nlh == NULL)
 636                 return -EMSGSIZE;
 637
 638         ndm = nlmsg_data(nlh);
 639         ndm->ndm_family  = AF_BRIDGE;
 640         ndm->ndm_pad1    = 0;
 641         ndm->ndm_pad2    = 0;
 642         ndm->ndm_flags   = fdb->added_by_external_learn ? NTF_EXT_LEARNED : 0;
 643         ndm->ndm_type    = 0;
 644         ndm->ndm_ifindex = fdb->dst ? fdb->dst->dev->ifindex : br->dev->ifindex;
 645         ndm->ndm_state   = fdb_to_nud(fdb);
 646
 647         if (nla_put(skb, NDA_LLADDR, ETH_ALEN, &fdb->addr))
 648                 goto nla_put_failure;
 649         if (nla_put_u32(skb, NDA_MASTER, br->dev->ifindex))
 650                 goto nla_put_failure;
 651         ci.ndm_used      = jiffies_to_clock_t(now - fdb->used);
 652         ci.ndm_confirmed = 0;
 653         ci.ndm_updated   = jiffies_to_clock_t(now - fdb->updated);
 654         ci.ndm_refcnt    = 0;
 655         if (nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci))
 656                 goto nla_put_failure;
 657
 658         if (fdb->vlan_id && nla_put(skb, NDA_VLAN, sizeof(u16), &fdb->vlan_id))
 659                 goto nla_put_failure;
 660
 661         nlmsg_end(skb, nlh);
 662         return 0;
 663
 664 nla_put_failure:
 665         nlmsg_cancel(skb, nlh);
 666         return -EMSGSIZE;
 667 }
 668
 669 static inline size_t fdb_nlmsg_size(void)
 670 {
 671         return NLMSG_ALIGN(sizeof(struct ndmsg))
 672                 + nla_total_size(ETH_ALEN) /* NDA_LLADDR */
 673                 + nla_total_size(sizeof(u32)) /* NDA_MASTER */
 674                 + nla_total_size(sizeof(u16)) /* NDA_VLAN */
 675                 + nla_total_size(sizeof(struct nda_cacheinfo));
 676 }
 677
 678 static void fdb_notify(struct net_bridge *br,
 679                        const struct net_bridge_fdb_entry *fdb, int type)
 680 {
 681         struct net *net = dev_net(br->dev);
 682         struct sk_buff *skb;
 683         int err = -ENOBUFS;
 684
 685         skb = nlmsg_new(fdb_nlmsg_size(), GFP_ATOMIC);
 686         if (skb == NULL)
 687                 goto errout;
 688
 689         err = fdb_fill_info(skb, br, fdb, 0, 0, type, 0);
 690         if (err < 0) {
 691                 /* -EMSGSIZE implies BUG in fdb_nlmsg_size() */
 692                 WARN_ON(err == -EMSGSIZE);
 693                 kfree_skb(skb);
 694                 goto errout;
 695         }
 696         rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
 697         return;
 698 errout:
 699         rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
 700 }
 701
 702 /* Dump information about entries, in response to GETNEIGH */
 703 int br_fdb_dump(struct sk_buff *skb,
 704                 struct netlink_callback *cb,
 705                 struct net_device *dev,
 706                 struct net_device *filter_dev,
 707                 int idx)
 708 {
 709         struct net_bridge *br = netdev_priv(dev);
 710         int i;
 711
 712         if (!(dev->priv_flags & IFF_EBRIDGE))
 713                 goto out;
 714
 715         if (!filter_dev)
 716                 idx = ndo_dflt_fdb_dump(skb, cb, dev, NULL, idx);
 717
 718         for (i = 0; i < BR_HASH_SIZE; i++) {
 719                 struct net_bridge_fdb_entry *f;
 720
 721                 hlist_for_each_entry_rcu(f, &br->hash[i], hlist) {
 722                         if (idx < cb->args[0])
 723                                 goto skip;
 724
 725                         if (filter_dev &&
 726                             (!f->dst || f->dst->dev != filter_dev)) {
 727                                 if (filter_dev != dev)
 728                                         goto skip;
 729                                 /* !f->dst is a special case for bridge
 730                                  * It means the MAC belongs to the bridge
 731                                  * Therefore need a little more filtering
 732                                  * we only want to dump the !f->dst case
 733                                  */
 734                                 if (f->dst)
 735                                         goto skip;
 736                         }
 737                         if (!filter_dev && f->dst)
 738                                 goto skip;
 739
 740                         if (fdb_fill_info(skb, br, f,
 741                                           NETLINK_CB(cb->skb).portid,
 742                                           cb->nlh->nlmsg_seq,
 743                                           RTM_NEWNEIGH,
 744                                           NLM_F_MULTI) < 0)
 745                                 break;
 746 skip:
 747                         ++idx;
 748                 }
 749         }
 750
 751 out:
 752         return idx;
 753 }
 754
 755 /* Update (create or replace) forwarding database entry */
 756 static int fdb_add_entry(struct net_bridge_port *source, const __u8 *addr,
 757                          __u16 state, __u16 flags, __u16 vid)
 758 {
 759         struct net_bridge *br = source->br;
 760         struct hlist_head *head = &br->hash[br_mac_hash(addr, vid)];
 761         struct net_bridge_fdb_entry *fdb;
 762         bool modified = false;
 763
 764         /* If the port cannot learn allow only local and static entries */
 765         if (!(state & NUD_PERMANENT) && !(state & NUD_NOARP) &&
 766             !(source->state == BR_STATE_LEARNING ||
 767               source->state == BR_STATE_FORWARDING))
 768                 return -EPERM;
 769
 770         fdb = fdb_find(head, addr, vid);
 771         if (fdb == NULL) {
 772                 if (!(flags & NLM_F_CREATE))
 773                         return -ENOENT;
 774
 775                 fdb = fdb_create(head, source, addr, vid);
 776                 if (!fdb)
 777                         return -ENOMEM;
 778
 779                 modified = true;
 780         } else {
 781                 if (flags & NLM_F_EXCL)
 782                         return -EEXIST;
 783
 784                 if (fdb->dst != source) {
 785                         fdb->dst = source;
 786                         modified = true;
 787                 }
 788         }
 789
 790         if (fdb_to_nud(fdb) != state) {
 791                 if (state & NUD_PERMANENT) {
 792                         fdb->is_local = 1;
 793                         if (!fdb->is_static) {
 794                                 fdb->is_static = 1;
 795                                 fdb_add_hw_addr(br, addr);
 796                         }
 797                 } else if (state & NUD_NOARP) {
 798                         fdb->is_local = 0;
 799                         if (!fdb->is_static) {
 800                                 fdb->is_static = 1;
 801                                 fdb_add_hw_addr(br, addr);
 802                         }
 803                 } else {
 804                         fdb->is_local = 0;
 805                         if (fdb->is_static) {
 806                                 fdb->is_static = 0;
 807                                 fdb_del_hw_addr(br, addr);
 808                         }
 809                 }
 810
 811                 modified = true;
 812         }
 813         fdb->added_by_user = 1;
 814
 815         fdb->used = jiffies;
 816         if (modified) {
 817                 fdb->updated = jiffies;
 818                 fdb_notify(br, fdb, RTM_NEWNEIGH);
 819         }
 820
 821         return 0;
 822 }
 823
 824 static int __br_fdb_add(struct ndmsg *ndm, struct net_bridge_port *p,
 825                const unsigned char *addr, u16 nlh_flags, u16 vid)
 826 {
 827         int err = 0;
 828
 829         if (ndm->ndm_flags & NTF_USE) {
 830                 local_bh_disable();
 831                 rcu_read_lock();
 832                 br_fdb_update(p->br, p, addr, vid, true);
 833                 rcu_read_unlock();
 834                 local_bh_enable();
 835         } else {
 836                 spin_lock_bh(&p->br->hash_lock);
 837                 err = fdb_add_entry(p, addr, ndm->ndm_state,
 838                                     nlh_flags, vid);
 839                 spin_unlock_bh(&p->br->hash_lock);
 840         }
 841
 842         return err;
 843 }
 844
 845 /* Add new permanent fdb entry with RTM_NEWNEIGH */
 846 int br_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
 847                struct net_device *dev,
 848                const unsigned char *addr, u16 vid, u16 nlh_flags)
 849 {
 850         struct net_bridge_vlan_group *vg;
 851         struct net_bridge_port *p;
 852         struct net_bridge_vlan *v;
 853         int err = 0;
 854
 855         if (!(ndm->ndm_state & (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE))) {
 856                 pr_info("bridge: RTM_NEWNEIGH with invalid state %#x\n", ndm->ndm_state);
 857                 return -EINVAL;
 858         }
 859
 860         if (is_zero_ether_addr(addr)) {
 861                 pr_info("bridge: RTM_NEWNEIGH with invalid ether address\n");
 862                 return -EINVAL;
 863         }
 864
 865         p = br_port_get_rtnl(dev);
 866         if (p == NULL) {
 867                 pr_info("bridge: RTM_NEWNEIGH %s not a bridge port\n",
 868                         dev->name);
 869                 return -EINVAL;
 870         }
 871
 872         vg = nbp_vlan_group(p);
 873         if (vid) {
 874                 v = br_vlan_find(vg, vid);
 875                 if (!v) {
 876                         pr_info("bridge: RTM_NEWNEIGH with unconfigured "
 877                                 "vlan %d on port %s\n", vid, dev->name);
 878                         return -EINVAL;
 879                 }
 880
 881                 /* VID was specified, so use it. */
 882                 err = __br_fdb_add(ndm, p, addr, nlh_flags, vid);
 883         } else {
 884                 err = __br_fdb_add(ndm, p, addr, nlh_flags, 0);
 885                 if (err || !vg || !vg->num_vlans)
 886                         goto out;
 887
 888                 /* We have vlans configured on this port and user didn't
 889                  * specify a VLAN.  To be nice, add/update entry for every
 890                  * vlan on this port.
 891                  */
 892                 list_for_each_entry(v, &vg->vlan_list, vlist) {
 893                         err = __br_fdb_add(ndm, p, addr, nlh_flags, v->vid);
 894                         if (err)
 895                                 goto out;
 896                 }
 897         }
 898
 899 out:
 900         return err;
 901 }
 902
 903 static int fdb_delete_by_addr_and_port(struct net_bridge_port *p,
 904                                        const u8 *addr, u16 vlan)
 905 {
 906         struct net_bridge *br = p->br;
 907         struct hlist_head *head = &br->hash[br_mac_hash(addr, vlan)];
 908         struct net_bridge_fdb_entry *fdb;
 909
 910         fdb = fdb_find(head, addr, vlan);
 911         if (!fdb || fdb->dst != p)
 912                 return -ENOENT;
 913
 914         fdb_delete(br, fdb);
 915         return 0;
 916 }
 917
 918 static int __br_fdb_delete(struct net_bridge_port *p,
 919                            const unsigned char *addr, u16 vid)
 920 {
 921         int err;
 922
 923         spin_lock_bh(&p->br->hash_lock);
 924         err = fdb_delete_by_addr_and_port(p, addr, vid);
 925         spin_unlock_bh(&p->br->hash_lock);
 926
 927         return err;
 928 }
 929
 930 /* Remove neighbor entry with RTM_DELNEIGH */
 931 int br_fdb_delete(struct ndmsg *ndm, struct nlattr *tb[],
 932                   struct net_device *dev,
 933                   const unsigned char *addr, u16 vid)
 934 {
 935         struct net_bridge_vlan_group *vg;
 936         struct net_bridge_port *p;
 937         struct net_bridge_vlan *v;
 938         int err;
 939
 940         p = br_port_get_rtnl(dev);
 941         if (p == NULL) {
 942                 pr_info("bridge: RTM_DELNEIGH %s not a bridge port\n",
 943                         dev->name);
 944                 return -EINVAL;
 945         }
 946
 947         vg = nbp_vlan_group(p);
 948         if (vid) {
 949                 v = br_vlan_find(vg, vid);
 950                 if (!v) {
 951                         pr_info("bridge: RTM_DELNEIGH with unconfigured "
 952                                 "vlan %d on port %s\n", vid, dev->name);
 953                         return -EINVAL;
 954                 }
 955
 956                 err = __br_fdb_delete(p, addr, vid);
 957         } else {
 958                 err = -ENOENT;
 959                 err &= __br_fdb_delete(p, addr, 0);
 960                 if (!vg || !vg->num_vlans)
 961                         goto out;
 962
 963                 list_for_each_entry(v, &vg->vlan_list, vlist)
 964                         err &= __br_fdb_delete(p, addr, v->vid);
 965         }
 966 out:
 967         return err;
 968 }
 969
 970 int br_fdb_sync_static(struct net_bridge *br, struct net_bridge_port *p)
 971 {
 972         struct net_bridge_fdb_entry *fdb, *tmp;
 973         int i;
 974         int err;
 975
 976         ASSERT_RTNL();
 977
 978         for (i = 0; i < BR_HASH_SIZE; i++) {
 979                 hlist_for_each_entry(fdb, &br->hash[i], hlist) {
 980                         /* We only care for static entries */
 981                         if (!fdb->is_static)
 982                                 continue;
 983
 984                         err = dev_uc_add(p->dev, fdb->addr.addr);
 985                         if (err)
 986                                 goto rollback;
 987                 }
 988         }
 989         return 0;
 990
 991 rollback:
 992         for (i = 0; i < BR_HASH_SIZE; i++) {
 993                 hlist_for_each_entry(tmp, &br->hash[i], hlist) {
 994                         /* If we reached the fdb that failed, we can stop */
 995                         if (tmp == fdb)
 996                                 break;
 997
 998                         /* We only care for static entries */
 999                         if (!tmp->is_static)
1000                                 continue;
1001
1002                         dev_uc_del(p->dev, tmp->addr.addr);
1003                 }
1004         }
1005         return err;
1006 }
1007
1008 void br_fdb_unsync_static(struct net_bridge *br, struct net_bridge_port *p)
1009 {
1010         struct net_bridge_fdb_entry *fdb;
1011         int i;
1012
1013         ASSERT_RTNL();
1014
1015         for (i = 0; i < BR_HASH_SIZE; i++) {
1016                 hlist_for_each_entry_rcu(fdb, &br->hash[i], hlist) {
1017                         /* We only care for static entries */
1018                         if (!fdb->is_static)
1019                                 continue;
1020
1021                         dev_uc_del(p->dev, fdb->addr.addr);
1022                 }
1023         }
1024 }
1025
1026 int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p,
1027                               const unsigned char *addr, u16 vid)
1028 {
1029         struct hlist_head *head;
1030         struct net_bridge_fdb_entry *fdb;
1031         int err = 0;
1032
1033         ASSERT_RTNL();
1034         spin_lock_bh(&br->hash_lock);
1035
1036         head = &br->hash[br_mac_hash(addr, vid)];
1037         fdb = fdb_find(head, addr, vid);
1038         if (!fdb) {
1039                 fdb = fdb_create(head, p, addr, vid);
1040                 if (!fdb) {
1041                         err = -ENOMEM;
1042                         goto err_unlock;
1043                 }
1044                 fdb->added_by_external_learn = 1;
1045                 fdb_notify(br, fdb, RTM_NEWNEIGH);
1046         } else if (fdb->added_by_external_learn) {
1047                 /* Refresh entry */
1048                 fdb->updated = fdb->used = jiffies;
1049         } else if (!fdb->added_by_user) {
1050                 /* Take over SW learned entry */
1051                 fdb->added_by_external_learn = 1;
1052                 fdb->updated = jiffies;
1053                 fdb_notify(br, fdb, RTM_NEWNEIGH);
1054         }
1055
1056 err_unlock:
1057         spin_unlock_bh(&br->hash_lock);
1058
1059         return err;
1060 }
1061
1062 int br_fdb_external_learn_del(struct net_bridge *br, struct net_bridge_port *p,
1063                               const unsigned char *addr, u16 vid)
1064 {
1065         struct hlist_head *head;
1066         struct net_bridge_fdb_entry *fdb;
1067         int err = 0;
1068
1069         ASSERT_RTNL();
1070         spin_lock_bh(&br->hash_lock);
1071
1072         head = &br->hash[br_mac_hash(addr, vid)];
1073         fdb = fdb_find(head, addr, vid);
1074         if (fdb && fdb->added_by_external_learn)
1075                 fdb_delete(br, fdb);
1076         else
1077                 err = -ENOENT;
1078
1079         spin_unlock_bh(&br->hash_lock);
1080
1081         return err;
1082 }