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v5.9
   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
  27static 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
  34static struct kmem_cache *br_fdb_cache __read_mostly;
  35static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
  36		      const unsigned char *addr, u16 vid);
  37static void fdb_notify(struct net_bridge *br,
  38		       const struct net_bridge_fdb_entry *, int, bool);
  39
  40int __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
  52void br_fdb_fini(void)
  53{
  54	kmem_cache_destroy(br_fdb_cache);
  55}
  56
  57int br_fdb_hash_init(struct net_bridge *br)
  58{
  59	return rhashtable_init(&br->fdb_hash_tbl, &br_fdb_rht_params);
  60}
  61
  62void 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 */
  70static inline unsigned long hold_time(const struct net_bridge *br)
  71{
  72	return br->topology_change ? br->forward_delay : br->ageing_time;
  73}
  74
  75static inline int has_expired(const struct net_bridge *br,
  76				  const struct net_bridge_fdb_entry *fdb)
  77{
  78	return !test_bit(BR_FDB_STATIC, &fdb->flags) &&
  79	       !test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags) &&
  80	       time_before_eq(fdb->updated + hold_time(br), jiffies);
  81}
  82
  83static void fdb_rcu_free(struct rcu_head *head)
  84{
  85	struct net_bridge_fdb_entry *ent
  86		= container_of(head, struct net_bridge_fdb_entry, rcu);
  87	kmem_cache_free(br_fdb_cache, ent);
  88}
  89
  90static struct net_bridge_fdb_entry *fdb_find_rcu(struct rhashtable *tbl,
  91						 const unsigned char *addr,
  92						 __u16 vid)
  93{
  94	struct net_bridge_fdb_key key;
  95
  96	WARN_ON_ONCE(!rcu_read_lock_held());
  97
  98	key.vlan_id = vid;
  99	memcpy(key.addr.addr, addr, sizeof(key.addr.addr));
 100
 101	return rhashtable_lookup(tbl, &key, br_fdb_rht_params);
 102}
 103
 104/* requires bridge hash_lock */
 105static struct net_bridge_fdb_entry *br_fdb_find(struct net_bridge *br,
 106						const unsigned char *addr,
 107						__u16 vid)
 108{
 109	struct net_bridge_fdb_entry *fdb;
 110
 111	lockdep_assert_held_once(&br->hash_lock);
 112
 113	rcu_read_lock();
 114	fdb = fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
 115	rcu_read_unlock();
 116
 117	return fdb;
 118}
 119
 120struct net_device *br_fdb_find_port(const struct net_device *br_dev,
 121				    const unsigned char *addr,
 122				    __u16 vid)
 123{
 124	struct net_bridge_fdb_entry *f;
 125	struct net_device *dev = NULL;
 126	struct net_bridge *br;
 127
 128	ASSERT_RTNL();
 129
 130	if (!netif_is_bridge_master(br_dev))
 131		return NULL;
 132
 133	br = netdev_priv(br_dev);
 134	rcu_read_lock();
 135	f = br_fdb_find_rcu(br, addr, vid);
 136	if (f && f->dst)
 137		dev = f->dst->dev;
 138	rcu_read_unlock();
 139
 140	return dev;
 141}
 142EXPORT_SYMBOL_GPL(br_fdb_find_port);
 143
 144struct net_bridge_fdb_entry *br_fdb_find_rcu(struct net_bridge *br,
 145					     const unsigned char *addr,
 146					     __u16 vid)
 147{
 148	return fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
 149}
 150
 151/* When a static FDB entry is added, the mac address from the entry is
 152 * added to the bridge private HW address list and all required ports
 153 * are then updated with the new information.
 154 * Called under RTNL.
 155 */
 156static void fdb_add_hw_addr(struct net_bridge *br, const unsigned char *addr)
 157{
 158	int err;
 159	struct net_bridge_port *p;
 160
 161	ASSERT_RTNL();
 162
 163	list_for_each_entry(p, &br->port_list, list) {
 164		if (!br_promisc_port(p)) {
 165			err = dev_uc_add(p->dev, addr);
 166			if (err)
 167				goto undo;
 168		}
 169	}
 170
 171	return;
 172undo:
 173	list_for_each_entry_continue_reverse(p, &br->port_list, list) {
 174		if (!br_promisc_port(p))
 175			dev_uc_del(p->dev, addr);
 176	}
 177}
 178
 179/* When a static FDB entry is deleted, the HW address from that entry is
 180 * also removed from the bridge private HW address list and updates all
 181 * the ports with needed information.
 182 * Called under RTNL.
 183 */
 184static void fdb_del_hw_addr(struct net_bridge *br, const unsigned char *addr)
 185{
 186	struct net_bridge_port *p;
 187
 188	ASSERT_RTNL();
 189
 190	list_for_each_entry(p, &br->port_list, list) {
 191		if (!br_promisc_port(p))
 192			dev_uc_del(p->dev, addr);
 193	}
 194}
 195
 196static void fdb_delete(struct net_bridge *br, struct net_bridge_fdb_entry *f,
 197		       bool swdev_notify)
 198{
 199	trace_fdb_delete(br, f);
 200
 201	if (test_bit(BR_FDB_STATIC, &f->flags))
 202		fdb_del_hw_addr(br, f->key.addr.addr);
 203
 204	hlist_del_init_rcu(&f->fdb_node);
 205	rhashtable_remove_fast(&br->fdb_hash_tbl, &f->rhnode,
 206			       br_fdb_rht_params);
 207	fdb_notify(br, f, RTM_DELNEIGH, swdev_notify);
 208	call_rcu(&f->rcu, fdb_rcu_free);
 209}
 210
 211/* Delete a local entry if no other port had the same address. */
 212static void fdb_delete_local(struct net_bridge *br,
 213			     const struct net_bridge_port *p,
 214			     struct net_bridge_fdb_entry *f)
 215{
 216	const unsigned char *addr = f->key.addr.addr;
 217	struct net_bridge_vlan_group *vg;
 218	const struct net_bridge_vlan *v;
 219	struct net_bridge_port *op;
 220	u16 vid = f->key.vlan_id;
 221
 222	/* Maybe another port has same hw addr? */
 223	list_for_each_entry(op, &br->port_list, list) {
 224		vg = nbp_vlan_group(op);
 225		if (op != p && ether_addr_equal(op->dev->dev_addr, addr) &&
 226		    (!vid || br_vlan_find(vg, vid))) {
 227			f->dst = op;
 228			clear_bit(BR_FDB_ADDED_BY_USER, &f->flags);
 229			return;
 230		}
 231	}
 232
 233	vg = br_vlan_group(br);
 234	v = br_vlan_find(vg, vid);
 235	/* Maybe bridge device has same hw addr? */
 236	if (p && ether_addr_equal(br->dev->dev_addr, addr) &&
 237	    (!vid || (v && br_vlan_should_use(v)))) {
 238		f->dst = NULL;
 239		clear_bit(BR_FDB_ADDED_BY_USER, &f->flags);
 240		return;
 241	}
 242
 243	fdb_delete(br, f, true);
 244}
 245
 246void br_fdb_find_delete_local(struct net_bridge *br,
 247			      const struct net_bridge_port *p,
 248			      const unsigned char *addr, u16 vid)
 249{
 250	struct net_bridge_fdb_entry *f;
 251
 252	spin_lock_bh(&br->hash_lock);
 253	f = br_fdb_find(br, addr, vid);
 254	if (f && test_bit(BR_FDB_LOCAL, &f->flags) &&
 255	    !test_bit(BR_FDB_ADDED_BY_USER, &f->flags) && f->dst == p)
 256		fdb_delete_local(br, p, f);
 257	spin_unlock_bh(&br->hash_lock);
 258}
 259
 260void br_fdb_changeaddr(struct net_bridge_port *p, const unsigned char *newaddr)
 261{
 262	struct net_bridge_vlan_group *vg;
 263	struct net_bridge_fdb_entry *f;
 264	struct net_bridge *br = p->br;
 265	struct net_bridge_vlan *v;
 266
 267	spin_lock_bh(&br->hash_lock);
 268	vg = nbp_vlan_group(p);
 269	hlist_for_each_entry(f, &br->fdb_list, fdb_node) {
 270		if (f->dst == p && test_bit(BR_FDB_LOCAL, &f->flags) &&
 271		    !test_bit(BR_FDB_ADDED_BY_USER, &f->flags)) {
 272			/* delete old one */
 273			fdb_delete_local(br, p, f);
 274
 275			/* if this port has no vlan information
 276			 * configured, we can safely be done at
 277			 * this point.
 278			 */
 279			if (!vg || !vg->num_vlans)
 280				goto insert;
 281		}
 282	}
 283
 284insert:
 285	/* insert new address,  may fail if invalid address or dup. */
 286	fdb_insert(br, p, newaddr, 0);
 287
 288	if (!vg || !vg->num_vlans)
 289		goto done;
 290
 291	/* Now add entries for every VLAN configured on the port.
 292	 * This function runs under RTNL so the bitmap will not change
 293	 * from under us.
 294	 */
 295	list_for_each_entry(v, &vg->vlan_list, vlist)
 296		fdb_insert(br, p, newaddr, v->vid);
 297
 298done:
 299	spin_unlock_bh(&br->hash_lock);
 300}
 301
 302void br_fdb_change_mac_address(struct net_bridge *br, const u8 *newaddr)
 303{
 304	struct net_bridge_vlan_group *vg;
 305	struct net_bridge_fdb_entry *f;
 306	struct net_bridge_vlan *v;
 307
 308	spin_lock_bh(&br->hash_lock);
 309
 310	/* If old entry was unassociated with any port, then delete it. */
 311	f = br_fdb_find(br, br->dev->dev_addr, 0);
 312	if (f && test_bit(BR_FDB_LOCAL, &f->flags) &&
 313	    !f->dst && !test_bit(BR_FDB_ADDED_BY_USER, &f->flags))
 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 && test_bit(BR_FDB_LOCAL, &f->flags) &&
 329		    !f->dst && !test_bit(BR_FDB_ADDED_BY_USER, &f->flags))
 330			fdb_delete_local(br, NULL, f);
 331		fdb_insert(br, NULL, newaddr, v->vid);
 332	}
 333out:
 334	spin_unlock_bh(&br->hash_lock);
 335}
 336
 337void br_fdb_cleanup(struct work_struct *work)
 338{
 339	struct net_bridge *br = container_of(work, struct net_bridge,
 340					     gc_work.work);
 341	struct net_bridge_fdb_entry *f = NULL;
 342	unsigned long delay = hold_time(br);
 343	unsigned long work_delay = delay;
 344	unsigned long now = jiffies;
 345
 346	/* this part is tricky, in order to avoid blocking learning and
 347	 * consequently forwarding, we rely on rcu to delete objects with
 348	 * delayed freeing allowing us to continue traversing
 349	 */
 350	rcu_read_lock();
 351	hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
 352		unsigned long this_timer = f->updated + delay;
 353
 354		if (test_bit(BR_FDB_STATIC, &f->flags) ||
 355		    test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &f->flags)) {
 356			if (test_bit(BR_FDB_NOTIFY, &f->flags)) {
 357				if (time_after(this_timer, now))
 358					work_delay = min(work_delay,
 359							 this_timer - now);
 360				else if (!test_and_set_bit(BR_FDB_NOTIFY_INACTIVE,
 361							   &f->flags))
 362					fdb_notify(br, f, RTM_NEWNEIGH, false);
 363			}
 364			continue;
 365		}
 366
 367		if (time_after(this_timer, now)) {
 368			work_delay = min(work_delay, this_timer - now);
 369		} else {
 370			spin_lock_bh(&br->hash_lock);
 371			if (!hlist_unhashed(&f->fdb_node))
 372				fdb_delete(br, f, true);
 373			spin_unlock_bh(&br->hash_lock);
 374		}
 375	}
 376	rcu_read_unlock();
 377
 378	/* Cleanup minimum 10 milliseconds apart */
 379	work_delay = max_t(unsigned long, work_delay, msecs_to_jiffies(10));
 380	mod_delayed_work(system_long_wq, &br->gc_work, work_delay);
 381}
 382
 383/* Completely flush all dynamic entries in forwarding database.*/
 384void br_fdb_flush(struct net_bridge *br)
 385{
 386	struct net_bridge_fdb_entry *f;
 387	struct hlist_node *tmp;
 388
 389	spin_lock_bh(&br->hash_lock);
 390	hlist_for_each_entry_safe(f, tmp, &br->fdb_list, fdb_node) {
 391		if (!test_bit(BR_FDB_STATIC, &f->flags))
 392			fdb_delete(br, f, true);
 393	}
 394	spin_unlock_bh(&br->hash_lock);
 395}
 396
 397/* Flush all entries referring to a specific port.
 398 * if do_all is set also flush static entries
 399 * if vid is set delete all entries that match the vlan_id
 400 */
 401void br_fdb_delete_by_port(struct net_bridge *br,
 402			   const struct net_bridge_port *p,
 403			   u16 vid,
 404			   int do_all)
 405{
 406	struct net_bridge_fdb_entry *f;
 407	struct hlist_node *tmp;
 408
 409	spin_lock_bh(&br->hash_lock);
 410	hlist_for_each_entry_safe(f, tmp, &br->fdb_list, fdb_node) {
 411		if (f->dst != p)
 412			continue;
 413
 414		if (!do_all)
 415			if (test_bit(BR_FDB_STATIC, &f->flags) ||
 416			    (test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &f->flags) &&
 417			     !test_bit(BR_FDB_OFFLOADED, &f->flags)) ||
 418			    (vid && f->key.vlan_id != vid))
 419				continue;
 420
 421		if (test_bit(BR_FDB_LOCAL, &f->flags))
 422			fdb_delete_local(br, p, f);
 423		else
 424			fdb_delete(br, f, true);
 425	}
 426	spin_unlock_bh(&br->hash_lock);
 427}
 428
 429#if IS_ENABLED(CONFIG_ATM_LANE)
 430/* Interface used by ATM LANE hook to test
 431 * if an addr is on some other bridge port */
 432int br_fdb_test_addr(struct net_device *dev, unsigned char *addr)
 433{
 434	struct net_bridge_fdb_entry *fdb;
 435	struct net_bridge_port *port;
 436	int ret;
 437
 438	rcu_read_lock();
 439	port = br_port_get_rcu(dev);
 440	if (!port)
 441		ret = 0;
 442	else {
 443		fdb = br_fdb_find_rcu(port->br, addr, 0);
 444		ret = fdb && fdb->dst && fdb->dst->dev != dev &&
 445			fdb->dst->state == BR_STATE_FORWARDING;
 446	}
 447	rcu_read_unlock();
 448
 449	return ret;
 450}
 451#endif /* CONFIG_ATM_LANE */
 452
 453/*
 454 * Fill buffer with forwarding table records in
 455 * the API format.
 456 */
 457int br_fdb_fillbuf(struct net_bridge *br, void *buf,
 458		   unsigned long maxnum, unsigned long skip)
 459{
 460	struct net_bridge_fdb_entry *f;
 461	struct __fdb_entry *fe = buf;
 462	int num = 0;
 463
 464	memset(buf, 0, maxnum*sizeof(struct __fdb_entry));
 465
 466	rcu_read_lock();
 467	hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
 468		if (num >= maxnum)
 469			break;
 470
 471		if (has_expired(br, f))
 472			continue;
 473
 474		/* ignore pseudo entry for local MAC address */
 475		if (!f->dst)
 476			continue;
 477
 478		if (skip) {
 479			--skip;
 480			continue;
 481		}
 482
 483		/* convert from internal format to API */
 484		memcpy(fe->mac_addr, f->key.addr.addr, ETH_ALEN);
 485
 486		/* due to ABI compat need to split into hi/lo */
 487		fe->port_no = f->dst->port_no;
 488		fe->port_hi = f->dst->port_no >> 8;
 489
 490		fe->is_local = test_bit(BR_FDB_LOCAL, &f->flags);
 491		if (!test_bit(BR_FDB_STATIC, &f->flags))
 492			fe->ageing_timer_value = jiffies_delta_to_clock_t(jiffies - f->updated);
 493		++fe;
 494		++num;
 495	}
 496	rcu_read_unlock();
 497
 498	return num;
 499}
 500
 501static struct net_bridge_fdb_entry *fdb_create(struct net_bridge *br,
 502					       struct net_bridge_port *source,
 503					       const unsigned char *addr,
 504					       __u16 vid,
 505					       unsigned long flags)
 
 506{
 507	struct net_bridge_fdb_entry *fdb;
 508
 509	fdb = kmem_cache_alloc(br_fdb_cache, GFP_ATOMIC);
 510	if (fdb) {
 511		memcpy(fdb->key.addr.addr, addr, ETH_ALEN);
 512		fdb->dst = source;
 513		fdb->key.vlan_id = vid;
 514		fdb->flags = flags;
 
 
 
 
 
 515		fdb->updated = fdb->used = jiffies;
 516		if (rhashtable_lookup_insert_fast(&br->fdb_hash_tbl,
 517						  &fdb->rhnode,
 518						  br_fdb_rht_params)) {
 519			kmem_cache_free(br_fdb_cache, fdb);
 520			fdb = NULL;
 521		} else {
 522			hlist_add_head_rcu(&fdb->fdb_node, &br->fdb_list);
 523		}
 524	}
 525	return fdb;
 526}
 527
 528static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
 529		  const unsigned char *addr, u16 vid)
 530{
 531	struct net_bridge_fdb_entry *fdb;
 532
 533	if (!is_valid_ether_addr(addr))
 534		return -EINVAL;
 535
 536	fdb = br_fdb_find(br, addr, vid);
 537	if (fdb) {
 538		/* it is okay to have multiple ports with same
 539		 * address, just use the first one.
 540		 */
 541		if (test_bit(BR_FDB_LOCAL, &fdb->flags))
 542			return 0;
 543		br_warn(br, "adding interface %s with same address as a received packet (addr:%pM, vlan:%u)\n",
 544		       source ? source->dev->name : br->dev->name, addr, vid);
 545		fdb_delete(br, fdb, true);
 546	}
 547
 548	fdb = fdb_create(br, source, addr, vid,
 549			 BIT(BR_FDB_LOCAL) | BIT(BR_FDB_STATIC));
 550	if (!fdb)
 551		return -ENOMEM;
 552
 553	fdb_add_hw_addr(br, addr);
 554	fdb_notify(br, fdb, RTM_NEWNEIGH, true);
 555	return 0;
 556}
 557
 558/* Add entry for local address of interface */
 559int br_fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
 560		  const unsigned char *addr, u16 vid)
 561{
 562	int ret;
 563
 564	spin_lock_bh(&br->hash_lock);
 565	ret = fdb_insert(br, source, addr, vid);
 566	spin_unlock_bh(&br->hash_lock);
 567	return ret;
 568}
 569
 570/* returns true if the fdb was modified */
 571static bool __fdb_mark_active(struct net_bridge_fdb_entry *fdb)
 572{
 573	return !!(test_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags) &&
 574		  test_and_clear_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags));
 575}
 576
 577void br_fdb_update(struct net_bridge *br, struct net_bridge_port *source,
 578		   const unsigned char *addr, u16 vid, unsigned long flags)
 579{
 580	struct net_bridge_fdb_entry *fdb;
 
 581
 582	/* some users want to always flood. */
 583	if (hold_time(br) == 0)
 584		return;
 585
 
 
 
 
 
 586	fdb = fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
 587	if (likely(fdb)) {
 588		/* attempt to update an entry for a local interface */
 589		if (unlikely(test_bit(BR_FDB_LOCAL, &fdb->flags))) {
 590			if (net_ratelimit())
 591				br_warn(br, "received packet on %s with own address as source address (addr:%pM, vlan:%u)\n",
 592					source->dev->name, addr, vid);
 593		} else {
 594			unsigned long now = jiffies;
 595			bool fdb_modified = false;
 596
 597			if (now != fdb->updated) {
 598				fdb->updated = now;
 599				fdb_modified = __fdb_mark_active(fdb);
 600			}
 601
 602			/* fastpath: update of existing entry */
 603			if (unlikely(source != fdb->dst &&
 604				     !test_bit(BR_FDB_STICKY, &fdb->flags))) {
 605				fdb->dst = source;
 606				fdb_modified = true;
 607				/* Take over HW learned entry */
 608				if (unlikely(test_bit(BR_FDB_ADDED_BY_EXT_LEARN,
 609						      &fdb->flags)))
 610					clear_bit(BR_FDB_ADDED_BY_EXT_LEARN,
 611						  &fdb->flags);
 612			}
 613
 614			if (unlikely(test_bit(BR_FDB_ADDED_BY_USER, &flags)))
 615				set_bit(BR_FDB_ADDED_BY_USER, &fdb->flags);
 
 616			if (unlikely(fdb_modified)) {
 617				trace_br_fdb_update(br, source, addr, vid, flags);
 618				fdb_notify(br, fdb, RTM_NEWNEIGH, true);
 619			}
 620		}
 621	} else {
 622		spin_lock(&br->hash_lock);
 623		fdb = fdb_create(br, source, addr, vid, flags);
 624		if (fdb) {
 625			trace_br_fdb_update(br, source, addr, vid, flags);
 
 
 
 626			fdb_notify(br, fdb, RTM_NEWNEIGH, true);
 627		}
 628		/* else  we lose race and someone else inserts
 629		 * it first, don't bother updating
 630		 */
 631		spin_unlock(&br->hash_lock);
 632	}
 633}
 634
 635static int fdb_to_nud(const struct net_bridge *br,
 636		      const struct net_bridge_fdb_entry *fdb)
 637{
 638	if (test_bit(BR_FDB_LOCAL, &fdb->flags))
 639		return NUD_PERMANENT;
 640	else if (test_bit(BR_FDB_STATIC, &fdb->flags))
 641		return NUD_NOARP;
 642	else if (has_expired(br, fdb))
 643		return NUD_STALE;
 644	else
 645		return NUD_REACHABLE;
 646}
 647
 648static int fdb_fill_info(struct sk_buff *skb, const struct net_bridge *br,
 649			 const struct net_bridge_fdb_entry *fdb,
 650			 u32 portid, u32 seq, int type, unsigned int flags)
 651{
 652	unsigned long now = jiffies;
 653	struct nda_cacheinfo ci;
 654	struct nlmsghdr *nlh;
 655	struct ndmsg *ndm;
 656
 657	nlh = nlmsg_put(skb, portid, seq, type, sizeof(*ndm), flags);
 658	if (nlh == NULL)
 659		return -EMSGSIZE;
 660
 661	ndm = nlmsg_data(nlh);
 662	ndm->ndm_family	 = AF_BRIDGE;
 663	ndm->ndm_pad1    = 0;
 664	ndm->ndm_pad2    = 0;
 665	ndm->ndm_flags	 = 0;
 666	ndm->ndm_type	 = 0;
 667	ndm->ndm_ifindex = fdb->dst ? fdb->dst->dev->ifindex : br->dev->ifindex;
 668	ndm->ndm_state   = fdb_to_nud(br, fdb);
 669
 670	if (test_bit(BR_FDB_OFFLOADED, &fdb->flags))
 671		ndm->ndm_flags |= NTF_OFFLOADED;
 672	if (test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags))
 673		ndm->ndm_flags |= NTF_EXT_LEARNED;
 674	if (test_bit(BR_FDB_STICKY, &fdb->flags))
 675		ndm->ndm_flags |= NTF_STICKY;
 676
 677	if (nla_put(skb, NDA_LLADDR, ETH_ALEN, &fdb->key.addr))
 678		goto nla_put_failure;
 679	if (nla_put_u32(skb, NDA_MASTER, br->dev->ifindex))
 680		goto nla_put_failure;
 681	ci.ndm_used	 = jiffies_to_clock_t(now - fdb->used);
 682	ci.ndm_confirmed = 0;
 683	ci.ndm_updated	 = jiffies_to_clock_t(now - fdb->updated);
 684	ci.ndm_refcnt	 = 0;
 685	if (nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci))
 686		goto nla_put_failure;
 687
 688	if (fdb->key.vlan_id && nla_put(skb, NDA_VLAN, sizeof(u16),
 689					&fdb->key.vlan_id))
 690		goto nla_put_failure;
 691
 692	if (test_bit(BR_FDB_NOTIFY, &fdb->flags)) {
 693		struct nlattr *nest = nla_nest_start(skb, NDA_FDB_EXT_ATTRS);
 694		u8 notify_bits = FDB_NOTIFY_BIT;
 695
 696		if (!nest)
 697			goto nla_put_failure;
 698		if (test_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags))
 699			notify_bits |= FDB_NOTIFY_INACTIVE_BIT;
 700
 701		if (nla_put_u8(skb, NFEA_ACTIVITY_NOTIFY, notify_bits)) {
 702			nla_nest_cancel(skb, nest);
 703			goto nla_put_failure;
 704		}
 705
 706		nla_nest_end(skb, nest);
 707	}
 708
 709	nlmsg_end(skb, nlh);
 710	return 0;
 711
 712nla_put_failure:
 713	nlmsg_cancel(skb, nlh);
 714	return -EMSGSIZE;
 715}
 716
 717static inline size_t fdb_nlmsg_size(void)
 718{
 719	return NLMSG_ALIGN(sizeof(struct ndmsg))
 720		+ nla_total_size(ETH_ALEN) /* NDA_LLADDR */
 721		+ nla_total_size(sizeof(u32)) /* NDA_MASTER */
 722		+ nla_total_size(sizeof(u16)) /* NDA_VLAN */
 723		+ nla_total_size(sizeof(struct nda_cacheinfo))
 724		+ nla_total_size(0) /* NDA_FDB_EXT_ATTRS */
 725		+ nla_total_size(sizeof(u8)); /* NFEA_ACTIVITY_NOTIFY */
 726}
 727
 728static void fdb_notify(struct net_bridge *br,
 729		       const struct net_bridge_fdb_entry *fdb, int type,
 730		       bool swdev_notify)
 731{
 732	struct net *net = dev_net(br->dev);
 733	struct sk_buff *skb;
 734	int err = -ENOBUFS;
 735
 736	if (swdev_notify)
 737		br_switchdev_fdb_notify(fdb, type);
 738
 739	skb = nlmsg_new(fdb_nlmsg_size(), GFP_ATOMIC);
 740	if (skb == NULL)
 741		goto errout;
 742
 743	err = fdb_fill_info(skb, br, fdb, 0, 0, type, 0);
 744	if (err < 0) {
 745		/* -EMSGSIZE implies BUG in fdb_nlmsg_size() */
 746		WARN_ON(err == -EMSGSIZE);
 747		kfree_skb(skb);
 748		goto errout;
 749	}
 750	rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
 751	return;
 752errout:
 753	rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
 754}
 755
 756/* Dump information about entries, in response to GETNEIGH */
 757int br_fdb_dump(struct sk_buff *skb,
 758		struct netlink_callback *cb,
 759		struct net_device *dev,
 760		struct net_device *filter_dev,
 761		int *idx)
 762{
 763	struct net_bridge *br = netdev_priv(dev);
 764	struct net_bridge_fdb_entry *f;
 765	int err = 0;
 766
 767	if (!(dev->priv_flags & IFF_EBRIDGE))
 768		return err;
 769
 770	if (!filter_dev) {
 771		err = ndo_dflt_fdb_dump(skb, cb, dev, NULL, idx);
 772		if (err < 0)
 773			return err;
 774	}
 775
 776	rcu_read_lock();
 777	hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
 778		if (*idx < cb->args[2])
 779			goto skip;
 780		if (filter_dev && (!f->dst || f->dst->dev != filter_dev)) {
 781			if (filter_dev != dev)
 782				goto skip;
 783			/* !f->dst is a special case for bridge
 784			 * It means the MAC belongs to the bridge
 785			 * Therefore need a little more filtering
 786			 * we only want to dump the !f->dst case
 787			 */
 788			if (f->dst)
 789				goto skip;
 790		}
 791		if (!filter_dev && f->dst)
 792			goto skip;
 793
 794		err = fdb_fill_info(skb, br, f,
 795				    NETLINK_CB(cb->skb).portid,
 796				    cb->nlh->nlmsg_seq,
 797				    RTM_NEWNEIGH,
 798				    NLM_F_MULTI);
 799		if (err < 0)
 800			break;
 801skip:
 802		*idx += 1;
 803	}
 804	rcu_read_unlock();
 805
 806	return err;
 807}
 808
 809int br_fdb_get(struct sk_buff *skb,
 810	       struct nlattr *tb[],
 811	       struct net_device *dev,
 812	       const unsigned char *addr,
 813	       u16 vid, u32 portid, u32 seq,
 814	       struct netlink_ext_ack *extack)
 815{
 816	struct net_bridge *br = netdev_priv(dev);
 817	struct net_bridge_fdb_entry *f;
 818	int err = 0;
 819
 820	rcu_read_lock();
 821	f = br_fdb_find_rcu(br, addr, vid);
 822	if (!f) {
 823		NL_SET_ERR_MSG(extack, "Fdb entry not found");
 824		err = -ENOENT;
 825		goto errout;
 826	}
 827
 828	err = fdb_fill_info(skb, br, f, portid, seq,
 829			    RTM_NEWNEIGH, 0);
 830errout:
 831	rcu_read_unlock();
 832	return err;
 833}
 834
 835/* returns true if the fdb is modified */
 836static bool fdb_handle_notify(struct net_bridge_fdb_entry *fdb, u8 notify)
 837{
 838	bool modified = false;
 839
 840	/* allow to mark an entry as inactive, usually done on creation */
 841	if ((notify & FDB_NOTIFY_INACTIVE_BIT) &&
 842	    !test_and_set_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags))
 843		modified = true;
 844
 845	if ((notify & FDB_NOTIFY_BIT) &&
 846	    !test_and_set_bit(BR_FDB_NOTIFY, &fdb->flags)) {
 847		/* enabled activity tracking */
 848		modified = true;
 849	} else if (!(notify & FDB_NOTIFY_BIT) &&
 850		   test_and_clear_bit(BR_FDB_NOTIFY, &fdb->flags)) {
 851		/* disabled activity tracking, clear notify state */
 852		clear_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags);
 853		modified = true;
 854	}
 855
 856	return modified;
 857}
 858
 859/* Update (create or replace) forwarding database entry */
 860static int fdb_add_entry(struct net_bridge *br, struct net_bridge_port *source,
 861			 const u8 *addr, struct ndmsg *ndm, u16 flags, u16 vid,
 862			 struct nlattr *nfea_tb[])
 863{
 864	bool is_sticky = !!(ndm->ndm_flags & NTF_STICKY);
 865	bool refresh = !nfea_tb[NFEA_DONT_REFRESH];
 866	struct net_bridge_fdb_entry *fdb;
 867	u16 state = ndm->ndm_state;
 868	bool modified = false;
 869	u8 notify = 0;
 870
 871	/* If the port cannot learn allow only local and static entries */
 872	if (source && !(state & NUD_PERMANENT) && !(state & NUD_NOARP) &&
 873	    !(source->state == BR_STATE_LEARNING ||
 874	      source->state == BR_STATE_FORWARDING))
 875		return -EPERM;
 876
 877	if (!source && !(state & NUD_PERMANENT)) {
 878		pr_info("bridge: RTM_NEWNEIGH %s without NUD_PERMANENT\n",
 879			br->dev->name);
 880		return -EINVAL;
 881	}
 882
 883	if (is_sticky && (state & NUD_PERMANENT))
 884		return -EINVAL;
 885
 886	if (nfea_tb[NFEA_ACTIVITY_NOTIFY]) {
 887		notify = nla_get_u8(nfea_tb[NFEA_ACTIVITY_NOTIFY]);
 888		if ((notify & ~BR_FDB_NOTIFY_SETTABLE_BITS) ||
 889		    (notify & BR_FDB_NOTIFY_SETTABLE_BITS) == FDB_NOTIFY_INACTIVE_BIT)
 890			return -EINVAL;
 891	}
 892
 893	fdb = br_fdb_find(br, addr, vid);
 894	if (fdb == NULL) {
 895		if (!(flags & NLM_F_CREATE))
 896			return -ENOENT;
 897
 898		fdb = fdb_create(br, source, addr, vid, 0);
 899		if (!fdb)
 900			return -ENOMEM;
 901
 902		modified = true;
 903	} else {
 904		if (flags & NLM_F_EXCL)
 905			return -EEXIST;
 906
 907		if (fdb->dst != source) {
 908			fdb->dst = source;
 909			modified = true;
 910		}
 911	}
 912
 913	if (fdb_to_nud(br, fdb) != state) {
 914		if (state & NUD_PERMANENT) {
 915			set_bit(BR_FDB_LOCAL, &fdb->flags);
 916			if (!test_and_set_bit(BR_FDB_STATIC, &fdb->flags))
 
 917				fdb_add_hw_addr(br, addr);
 
 918		} else if (state & NUD_NOARP) {
 919			clear_bit(BR_FDB_LOCAL, &fdb->flags);
 920			if (!test_and_set_bit(BR_FDB_STATIC, &fdb->flags))
 
 921				fdb_add_hw_addr(br, addr);
 
 922		} else {
 923			clear_bit(BR_FDB_LOCAL, &fdb->flags);
 924			if (test_and_clear_bit(BR_FDB_STATIC, &fdb->flags))
 
 925				fdb_del_hw_addr(br, addr);
 
 926		}
 927
 928		modified = true;
 929	}
 930
 931	if (is_sticky != test_bit(BR_FDB_STICKY, &fdb->flags)) {
 932		change_bit(BR_FDB_STICKY, &fdb->flags);
 933		modified = true;
 934	}
 935
 936	if (fdb_handle_notify(fdb, notify))
 937		modified = true;
 938
 939	set_bit(BR_FDB_ADDED_BY_USER, &fdb->flags);
 940
 941	fdb->used = jiffies;
 942	if (modified) {
 943		if (refresh)
 944			fdb->updated = jiffies;
 945		fdb_notify(br, fdb, RTM_NEWNEIGH, true);
 946	}
 947
 948	return 0;
 949}
 950
 951static int __br_fdb_add(struct ndmsg *ndm, struct net_bridge *br,
 952			struct net_bridge_port *p, const unsigned char *addr,
 953			u16 nlh_flags, u16 vid, struct nlattr *nfea_tb[])
 954{
 955	int err = 0;
 956
 957	if (ndm->ndm_flags & NTF_USE) {
 958		if (!p) {
 959			pr_info("bridge: RTM_NEWNEIGH %s with NTF_USE is not supported\n",
 960				br->dev->name);
 961			return -EINVAL;
 962		}
 963		if (!nbp_state_should_learn(p))
 964			return 0;
 965
 966		local_bh_disable();
 967		rcu_read_lock();
 968		br_fdb_update(br, p, addr, vid, BIT(BR_FDB_ADDED_BY_USER));
 969		rcu_read_unlock();
 970		local_bh_enable();
 971	} else if (ndm->ndm_flags & NTF_EXT_LEARNED) {
 972		err = br_fdb_external_learn_add(br, p, addr, vid, true);
 973	} else {
 974		spin_lock_bh(&br->hash_lock);
 975		err = fdb_add_entry(br, p, addr, ndm, nlh_flags, vid, nfea_tb);
 
 976		spin_unlock_bh(&br->hash_lock);
 977	}
 978
 979	return err;
 980}
 981
 982static const struct nla_policy br_nda_fdb_pol[NFEA_MAX + 1] = {
 983	[NFEA_ACTIVITY_NOTIFY]	= { .type = NLA_U8 },
 984	[NFEA_DONT_REFRESH]	= { .type = NLA_FLAG },
 985};
 986
 987/* Add new permanent fdb entry with RTM_NEWNEIGH */
 988int br_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
 989	       struct net_device *dev,
 990	       const unsigned char *addr, u16 vid, u16 nlh_flags,
 991	       struct netlink_ext_ack *extack)
 992{
 993	struct nlattr *nfea_tb[NFEA_MAX + 1], *attr;
 994	struct net_bridge_vlan_group *vg;
 995	struct net_bridge_port *p = NULL;
 996	struct net_bridge_vlan *v;
 997	struct net_bridge *br = NULL;
 998	int err = 0;
 999
1000	trace_br_fdb_add(ndm, dev, addr, vid, nlh_flags);
1001
1002	if (!(ndm->ndm_state & (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE))) {
1003		pr_info("bridge: RTM_NEWNEIGH with invalid state %#x\n", ndm->ndm_state);
1004		return -EINVAL;
1005	}
1006
1007	if (is_zero_ether_addr(addr)) {
1008		pr_info("bridge: RTM_NEWNEIGH with invalid ether address\n");
1009		return -EINVAL;
1010	}
1011
1012	if (dev->priv_flags & IFF_EBRIDGE) {
1013		br = netdev_priv(dev);
1014		vg = br_vlan_group(br);
1015	} else {
1016		p = br_port_get_rtnl(dev);
1017		if (!p) {
1018			pr_info("bridge: RTM_NEWNEIGH %s not a bridge port\n",
1019				dev->name);
1020			return -EINVAL;
1021		}
1022		br = p->br;
1023		vg = nbp_vlan_group(p);
1024	}
1025
1026	if (tb[NDA_FDB_EXT_ATTRS]) {
1027		attr = tb[NDA_FDB_EXT_ATTRS];
1028		err = nla_parse_nested(nfea_tb, NFEA_MAX, attr,
1029				       br_nda_fdb_pol, extack);
1030		if (err)
1031			return err;
1032	} else {
1033		memset(nfea_tb, 0, sizeof(struct nlattr *) * (NFEA_MAX + 1));
1034	}
1035
1036	if (vid) {
1037		v = br_vlan_find(vg, vid);
1038		if (!v || !br_vlan_should_use(v)) {
1039			pr_info("bridge: RTM_NEWNEIGH with unconfigured vlan %d on %s\n", vid, dev->name);
1040			return -EINVAL;
1041		}
1042
1043		/* VID was specified, so use it. */
1044		err = __br_fdb_add(ndm, br, p, addr, nlh_flags, vid, nfea_tb);
1045	} else {
1046		err = __br_fdb_add(ndm, br, p, addr, nlh_flags, 0, nfea_tb);
1047		if (err || !vg || !vg->num_vlans)
1048			goto out;
1049
1050		/* We have vlans configured on this port and user didn't
1051		 * specify a VLAN.  To be nice, add/update entry for every
1052		 * vlan on this port.
1053		 */
1054		list_for_each_entry(v, &vg->vlan_list, vlist) {
1055			if (!br_vlan_should_use(v))
1056				continue;
1057			err = __br_fdb_add(ndm, br, p, addr, nlh_flags, v->vid,
1058					   nfea_tb);
1059			if (err)
1060				goto out;
1061		}
1062	}
1063
1064out:
1065	return err;
1066}
1067
1068static int fdb_delete_by_addr_and_port(struct net_bridge *br,
1069				       const struct net_bridge_port *p,
1070				       const u8 *addr, u16 vlan)
1071{
1072	struct net_bridge_fdb_entry *fdb;
1073
1074	fdb = br_fdb_find(br, addr, vlan);
1075	if (!fdb || fdb->dst != p)
1076		return -ENOENT;
1077
1078	fdb_delete(br, fdb, true);
1079
1080	return 0;
1081}
1082
1083static int __br_fdb_delete(struct net_bridge *br,
1084			   const struct net_bridge_port *p,
1085			   const unsigned char *addr, u16 vid)
1086{
1087	int err;
1088
1089	spin_lock_bh(&br->hash_lock);
1090	err = fdb_delete_by_addr_and_port(br, p, addr, vid);
1091	spin_unlock_bh(&br->hash_lock);
1092
1093	return err;
1094}
1095
1096/* Remove neighbor entry with RTM_DELNEIGH */
1097int br_fdb_delete(struct ndmsg *ndm, struct nlattr *tb[],
1098		  struct net_device *dev,
1099		  const unsigned char *addr, u16 vid)
1100{
1101	struct net_bridge_vlan_group *vg;
1102	struct net_bridge_port *p = NULL;
1103	struct net_bridge_vlan *v;
1104	struct net_bridge *br;
1105	int err;
1106
1107	if (dev->priv_flags & IFF_EBRIDGE) {
1108		br = netdev_priv(dev);
1109		vg = br_vlan_group(br);
1110	} else {
1111		p = br_port_get_rtnl(dev);
1112		if (!p) {
1113			pr_info("bridge: RTM_DELNEIGH %s not a bridge port\n",
1114				dev->name);
1115			return -EINVAL;
1116		}
1117		vg = nbp_vlan_group(p);
1118		br = p->br;
1119	}
1120
1121	if (vid) {
1122		v = br_vlan_find(vg, vid);
1123		if (!v) {
1124			pr_info("bridge: RTM_DELNEIGH with unconfigured vlan %d on %s\n", vid, dev->name);
1125			return -EINVAL;
1126		}
1127
1128		err = __br_fdb_delete(br, p, addr, vid);
1129	} else {
1130		err = -ENOENT;
1131		err &= __br_fdb_delete(br, p, addr, 0);
1132		if (!vg || !vg->num_vlans)
1133			return err;
1134
1135		list_for_each_entry(v, &vg->vlan_list, vlist) {
1136			if (!br_vlan_should_use(v))
1137				continue;
1138			err &= __br_fdb_delete(br, p, addr, v->vid);
1139		}
1140	}
1141
1142	return err;
1143}
1144
1145int br_fdb_sync_static(struct net_bridge *br, struct net_bridge_port *p)
1146{
1147	struct net_bridge_fdb_entry *f, *tmp;
1148	int err = 0;
1149
1150	ASSERT_RTNL();
1151
1152	/* the key here is that static entries change only under rtnl */
1153	rcu_read_lock();
1154	hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
1155		/* We only care for static entries */
1156		if (!test_bit(BR_FDB_STATIC, &f->flags))
1157			continue;
1158		err = dev_uc_add(p->dev, f->key.addr.addr);
1159		if (err)
1160			goto rollback;
1161	}
1162done:
1163	rcu_read_unlock();
1164
1165	return err;
1166
1167rollback:
1168	hlist_for_each_entry_rcu(tmp, &br->fdb_list, fdb_node) {
1169		/* We only care for static entries */
1170		if (!test_bit(BR_FDB_STATIC, &tmp->flags))
1171			continue;
1172		if (tmp == f)
1173			break;
1174		dev_uc_del(p->dev, tmp->key.addr.addr);
1175	}
1176
1177	goto done;
1178}
1179
1180void br_fdb_unsync_static(struct net_bridge *br, struct net_bridge_port *p)
1181{
1182	struct net_bridge_fdb_entry *f;
1183
1184	ASSERT_RTNL();
1185
1186	rcu_read_lock();
1187	hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
1188		/* We only care for static entries */
1189		if (!test_bit(BR_FDB_STATIC, &f->flags))
1190			continue;
1191
1192		dev_uc_del(p->dev, f->key.addr.addr);
1193	}
1194	rcu_read_unlock();
1195}
1196
1197int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p,
1198			      const unsigned char *addr, u16 vid,
1199			      bool swdev_notify)
1200{
1201	struct net_bridge_fdb_entry *fdb;
1202	bool modified = false;
1203	int err = 0;
1204
1205	trace_br_fdb_external_learn_add(br, p, addr, vid);
1206
1207	spin_lock_bh(&br->hash_lock);
1208
1209	fdb = br_fdb_find(br, addr, vid);
1210	if (!fdb) {
1211		unsigned long flags = BIT(BR_FDB_ADDED_BY_EXT_LEARN);
1212
1213		if (swdev_notify)
1214			flags |= BIT(BR_FDB_ADDED_BY_USER);
1215		fdb = fdb_create(br, p, addr, vid, flags);
1216		if (!fdb) {
1217			err = -ENOMEM;
1218			goto err_unlock;
1219		}
 
 
 
1220		fdb_notify(br, fdb, RTM_NEWNEIGH, swdev_notify);
1221	} else {
1222		fdb->updated = jiffies;
1223
1224		if (fdb->dst != p) {
1225			fdb->dst = p;
1226			modified = true;
1227		}
1228
1229		if (test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags)) {
1230			/* Refresh entry */
1231			fdb->used = jiffies;
1232		} else if (!test_bit(BR_FDB_ADDED_BY_USER, &fdb->flags)) {
1233			/* Take over SW learned entry */
1234			set_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags);
1235			modified = true;
1236		}
1237
1238		if (swdev_notify)
1239			set_bit(BR_FDB_ADDED_BY_USER, &fdb->flags);
1240
1241		if (modified)
1242			fdb_notify(br, fdb, RTM_NEWNEIGH, swdev_notify);
1243	}
1244
1245err_unlock:
1246	spin_unlock_bh(&br->hash_lock);
1247
1248	return err;
1249}
1250
1251int br_fdb_external_learn_del(struct net_bridge *br, struct net_bridge_port *p,
1252			      const unsigned char *addr, u16 vid,
1253			      bool swdev_notify)
1254{
1255	struct net_bridge_fdb_entry *fdb;
1256	int err = 0;
1257
1258	spin_lock_bh(&br->hash_lock);
1259
1260	fdb = br_fdb_find(br, addr, vid);
1261	if (fdb && test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags))
1262		fdb_delete(br, fdb, swdev_notify);
1263	else
1264		err = -ENOENT;
1265
1266	spin_unlock_bh(&br->hash_lock);
1267
1268	return err;
1269}
1270
1271void br_fdb_offloaded_set(struct net_bridge *br, struct net_bridge_port *p,
1272			  const unsigned char *addr, u16 vid, bool offloaded)
1273{
1274	struct net_bridge_fdb_entry *fdb;
1275
1276	spin_lock_bh(&br->hash_lock);
1277
1278	fdb = br_fdb_find(br, addr, vid);
1279	if (fdb && offloaded != test_bit(BR_FDB_OFFLOADED, &fdb->flags))
1280		change_bit(BR_FDB_OFFLOADED, &fdb->flags);
1281
1282	spin_unlock_bh(&br->hash_lock);
1283}
1284
1285void br_fdb_clear_offload(const struct net_device *dev, u16 vid)
1286{
1287	struct net_bridge_fdb_entry *f;
1288	struct net_bridge_port *p;
1289
1290	ASSERT_RTNL();
1291
1292	p = br_port_get_rtnl(dev);
1293	if (!p)
1294		return;
1295
1296	spin_lock_bh(&p->br->hash_lock);
1297	hlist_for_each_entry(f, &p->br->fdb_list, fdb_node) {
1298		if (f->dst == p && f->key.vlan_id == vid)
1299			clear_bit(BR_FDB_OFFLOADED, &f->flags);
1300	}
1301	spin_unlock_bh(&p->br->hash_lock);
1302}
1303EXPORT_SYMBOL_GPL(br_fdb_clear_offload);
v5.4
   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
  27static 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
  34static struct kmem_cache *br_fdb_cache __read_mostly;
  35static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
  36		      const unsigned char *addr, u16 vid);
  37static void fdb_notify(struct net_bridge *br,
  38		       const struct net_bridge_fdb_entry *, int, bool);
  39
  40int __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
  52void br_fdb_fini(void)
  53{
  54	kmem_cache_destroy(br_fdb_cache);
  55}
  56
  57int br_fdb_hash_init(struct net_bridge *br)
  58{
  59	return rhashtable_init(&br->fdb_hash_tbl, &br_fdb_rht_params);
  60}
  61
  62void 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 */
  70static inline unsigned long hold_time(const struct net_bridge *br)
  71{
  72	return br->topology_change ? br->forward_delay : br->ageing_time;
  73}
  74
  75static 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
  82static 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
  89static 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 */
 104static 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
 119struct 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}
 141EXPORT_SYMBOL_GPL(br_fdb_find_port);
 142
 143struct 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 */
 155static 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;
 171undo:
 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 */
 183static 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
 195static 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. */
 211static 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
 245void 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
 258void 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
 281insert:
 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
 295done:
 296	spin_unlock_bh(&br->hash_lock);
 297}
 298
 299void 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	}
 328out:
 329	spin_unlock_bh(&br->hash_lock);
 330}
 331
 332void 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.*/
 369void 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 */
 386void 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 */
 414int 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 */
 439int 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
 483static 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
 516static 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 */
 546int 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
 
 
 
 
 
 
 
 557void 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
 616static 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
 629static 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
 676nla_put_failure:
 677	nlmsg_cancel(skb, nlh);
 678	return -EMSGSIZE;
 679}
 680
 681static 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
 690static 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;
 714errout:
 715	rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
 716}
 717
 718/* Dump information about entries, in response to GETNEIGH */
 719int 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;
 763skip:
 764		*idx += 1;
 765	}
 766	rcu_read_unlock();
 767
 768	return err;
 769}
 770
 771int 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);
 792errout:
 793	rcu_read_unlock();
 794	return err;
 795}
 796
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 797/* Update (create or replace) forwarding database entry */
 798static 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
 881static 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 */
 911int 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
 975out:
 976	return err;
 977}
 978
 979static 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
 994static 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 */
1008int 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
1056int 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	}
1073done:
1074	rcu_read_unlock();
1075
1076	return err;
1077
1078rollback:
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
1091void 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
1108int 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
1155err_unlock:
1156	spin_unlock_bh(&br->hash_lock);
1157
1158	return err;
1159}
1160
1161int 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
1181void 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
1195void 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}
1213EXPORT_SYMBOL_GPL(br_fdb_clear_offload);