xref: /linux/net/bridge/br_fdb.c (revision 8a5f956a9fb7d74fff681145082acfad5afa6bb8)
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 <linux/unaligned.h>
22 #include <linux/if_vlan.h>
23 #include <net/switchdev.h>
24 #include <trace/events/bridge.h>
25 #include "br_private.h"
26 
27 static const struct rhashtable_params br_fdb_rht_params = {
28 	.head_offset = offsetof(struct net_bridge_fdb_entry, rhnode),
29 	.key_offset = offsetof(struct net_bridge_fdb_entry, key),
30 	.key_len = sizeof(struct net_bridge_fdb_key),
31 	.automatic_shrinking = true,
32 };
33 
34 static struct kmem_cache *br_fdb_cache __read_mostly;
35 
36 int __init br_fdb_init(void)
37 {
38 	br_fdb_cache = KMEM_CACHE(net_bridge_fdb_entry, SLAB_HWCACHE_ALIGN);
39 	if (!br_fdb_cache)
40 		return -ENOMEM;
41 
42 	return 0;
43 }
44 
45 void br_fdb_fini(void)
46 {
47 	kmem_cache_destroy(br_fdb_cache);
48 }
49 
50 int br_fdb_hash_init(struct net_bridge *br)
51 {
52 	return rhashtable_init(&br->fdb_hash_tbl, &br_fdb_rht_params);
53 }
54 
55 void br_fdb_hash_fini(struct net_bridge *br)
56 {
57 	rhashtable_destroy(&br->fdb_hash_tbl);
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 !test_bit(BR_FDB_STATIC, &fdb->flags) &&
72 	       !test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags) &&
73 	       time_before_eq(fdb->updated + hold_time(br), jiffies);
74 }
75 
76 static int fdb_to_nud(const struct net_bridge *br,
77 		      const struct net_bridge_fdb_entry *fdb)
78 {
79 	if (test_bit(BR_FDB_LOCAL, &fdb->flags))
80 		return NUD_PERMANENT;
81 	else if (test_bit(BR_FDB_STATIC, &fdb->flags))
82 		return NUD_NOARP;
83 	else if (has_expired(br, fdb))
84 		return NUD_STALE;
85 	else
86 		return NUD_REACHABLE;
87 }
88 
89 static int fdb_fill_info(struct sk_buff *skb, const struct net_bridge *br,
90 			 const struct net_bridge_fdb_entry *fdb,
91 			 u32 portid, u32 seq, int type, unsigned int flags)
92 {
93 	const struct net_bridge_port *dst = READ_ONCE(fdb->dst);
94 	unsigned long now = jiffies;
95 	struct nda_cacheinfo ci;
96 	struct nlmsghdr *nlh;
97 	struct ndmsg *ndm;
98 	u32 ext_flags = 0;
99 
100 	nlh = nlmsg_put(skb, portid, seq, type, sizeof(*ndm), flags);
101 	if (nlh == NULL)
102 		return -EMSGSIZE;
103 
104 	ndm = nlmsg_data(nlh);
105 	ndm->ndm_family	 = AF_BRIDGE;
106 	ndm->ndm_pad1    = 0;
107 	ndm->ndm_pad2    = 0;
108 	ndm->ndm_flags	 = 0;
109 	ndm->ndm_type	 = 0;
110 	ndm->ndm_ifindex = dst ? dst->dev->ifindex : br->dev->ifindex;
111 	ndm->ndm_state   = fdb_to_nud(br, fdb);
112 
113 	if (test_bit(BR_FDB_OFFLOADED, &fdb->flags))
114 		ndm->ndm_flags |= NTF_OFFLOADED;
115 	if (test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags))
116 		ndm->ndm_flags |= NTF_EXT_LEARNED;
117 	if (test_bit(BR_FDB_STICKY, &fdb->flags))
118 		ndm->ndm_flags |= NTF_STICKY;
119 	if (test_bit(BR_FDB_LOCKED, &fdb->flags))
120 		ext_flags |= NTF_EXT_LOCKED;
121 
122 	if (nla_put(skb, NDA_LLADDR, ETH_ALEN, &fdb->key.addr))
123 		goto nla_put_failure;
124 	if (nla_put_u32(skb, NDA_MASTER, br->dev->ifindex))
125 		goto nla_put_failure;
126 	if (nla_put_u32(skb, NDA_FLAGS_EXT, ext_flags))
127 		goto nla_put_failure;
128 
129 	ci.ndm_used	 = jiffies_to_clock_t(now - fdb->used);
130 	ci.ndm_confirmed = 0;
131 	ci.ndm_updated	 = jiffies_to_clock_t(now - fdb->updated);
132 	ci.ndm_refcnt	 = 0;
133 	if (nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci))
134 		goto nla_put_failure;
135 
136 	if (fdb->key.vlan_id && nla_put(skb, NDA_VLAN, sizeof(u16),
137 					&fdb->key.vlan_id))
138 		goto nla_put_failure;
139 
140 	if (test_bit(BR_FDB_NOTIFY, &fdb->flags)) {
141 		struct nlattr *nest = nla_nest_start(skb, NDA_FDB_EXT_ATTRS);
142 		u8 notify_bits = FDB_NOTIFY_BIT;
143 
144 		if (!nest)
145 			goto nla_put_failure;
146 		if (test_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags))
147 			notify_bits |= FDB_NOTIFY_INACTIVE_BIT;
148 
149 		if (nla_put_u8(skb, NFEA_ACTIVITY_NOTIFY, notify_bits)) {
150 			nla_nest_cancel(skb, nest);
151 			goto nla_put_failure;
152 		}
153 
154 		nla_nest_end(skb, nest);
155 	}
156 
157 	nlmsg_end(skb, nlh);
158 	return 0;
159 
160 nla_put_failure:
161 	nlmsg_cancel(skb, nlh);
162 	return -EMSGSIZE;
163 }
164 
165 static inline size_t fdb_nlmsg_size(void)
166 {
167 	return NLMSG_ALIGN(sizeof(struct ndmsg))
168 		+ nla_total_size(ETH_ALEN) /* NDA_LLADDR */
169 		+ nla_total_size(sizeof(u32)) /* NDA_MASTER */
170 		+ nla_total_size(sizeof(u32)) /* NDA_FLAGS_EXT */
171 		+ nla_total_size(sizeof(u16)) /* NDA_VLAN */
172 		+ nla_total_size(sizeof(struct nda_cacheinfo))
173 		+ nla_total_size(0) /* NDA_FDB_EXT_ATTRS */
174 		+ nla_total_size(sizeof(u8)); /* NFEA_ACTIVITY_NOTIFY */
175 }
176 
177 static void fdb_notify(struct net_bridge *br,
178 		       const struct net_bridge_fdb_entry *fdb, int type,
179 		       bool swdev_notify)
180 {
181 	struct net *net = dev_net(br->dev);
182 	struct sk_buff *skb;
183 	int err = -ENOBUFS;
184 
185 	if (swdev_notify)
186 		br_switchdev_fdb_notify(br, fdb, type);
187 
188 	skb = nlmsg_new(fdb_nlmsg_size(), GFP_ATOMIC);
189 	if (skb == NULL)
190 		goto errout;
191 
192 	err = fdb_fill_info(skb, br, fdb, 0, 0, type, 0);
193 	if (err < 0) {
194 		/* -EMSGSIZE implies BUG in fdb_nlmsg_size() */
195 		WARN_ON(err == -EMSGSIZE);
196 		kfree_skb(skb);
197 		goto errout;
198 	}
199 	rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
200 	return;
201 errout:
202 	rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
203 }
204 
205 static struct net_bridge_fdb_entry *fdb_find_rcu(struct rhashtable *tbl,
206 						 const unsigned char *addr,
207 						 __u16 vid)
208 {
209 	struct net_bridge_fdb_key key;
210 
211 	WARN_ON_ONCE(!rcu_read_lock_held());
212 
213 	key.vlan_id = vid;
214 	memcpy(key.addr.addr, addr, sizeof(key.addr.addr));
215 
216 	return rhashtable_lookup(tbl, &key, br_fdb_rht_params);
217 }
218 
219 /* requires bridge hash_lock */
220 static struct net_bridge_fdb_entry *br_fdb_find(struct net_bridge *br,
221 						const unsigned char *addr,
222 						__u16 vid)
223 {
224 	struct net_bridge_fdb_entry *fdb;
225 
226 	lockdep_assert_held_once(&br->hash_lock);
227 
228 	rcu_read_lock();
229 	fdb = fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
230 	rcu_read_unlock();
231 
232 	return fdb;
233 }
234 
235 struct net_device *br_fdb_find_port(const struct net_device *br_dev,
236 				    const unsigned char *addr,
237 				    __u16 vid)
238 {
239 	struct net_bridge_fdb_entry *f;
240 	struct net_device *dev = NULL;
241 	struct net_bridge *br;
242 
243 	ASSERT_RTNL();
244 
245 	if (!netif_is_bridge_master(br_dev))
246 		return NULL;
247 
248 	br = netdev_priv(br_dev);
249 	rcu_read_lock();
250 	f = br_fdb_find_rcu(br, addr, vid);
251 	if (f && f->dst)
252 		dev = f->dst->dev;
253 	rcu_read_unlock();
254 
255 	return dev;
256 }
257 EXPORT_SYMBOL_GPL(br_fdb_find_port);
258 
259 struct net_bridge_fdb_entry *br_fdb_find_rcu(struct net_bridge *br,
260 					     const unsigned char *addr,
261 					     __u16 vid)
262 {
263 	return fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
264 }
265 
266 /* When a static FDB entry is added, the mac address from the entry is
267  * added to the bridge private HW address list and all required ports
268  * are then updated with the new information.
269  * Called under RTNL.
270  */
271 static void fdb_add_hw_addr(struct net_bridge *br, const unsigned char *addr)
272 {
273 	int err;
274 	struct net_bridge_port *p;
275 
276 	ASSERT_RTNL();
277 
278 	list_for_each_entry(p, &br->port_list, list) {
279 		if (!br_promisc_port(p)) {
280 			err = dev_uc_add(p->dev, addr);
281 			if (err)
282 				goto undo;
283 		}
284 	}
285 
286 	return;
287 undo:
288 	list_for_each_entry_continue_reverse(p, &br->port_list, list) {
289 		if (!br_promisc_port(p))
290 			dev_uc_del(p->dev, addr);
291 	}
292 }
293 
294 /* When a static FDB entry is deleted, the HW address from that entry is
295  * also removed from the bridge private HW address list and updates all
296  * the ports with needed information.
297  * Called under RTNL.
298  */
299 static void fdb_del_hw_addr(struct net_bridge *br, const unsigned char *addr)
300 {
301 	struct net_bridge_port *p;
302 
303 	ASSERT_RTNL();
304 
305 	list_for_each_entry(p, &br->port_list, list) {
306 		if (!br_promisc_port(p))
307 			dev_uc_del(p->dev, addr);
308 	}
309 }
310 
311 static void fdb_delete(struct net_bridge *br, struct net_bridge_fdb_entry *f,
312 		       bool swdev_notify)
313 {
314 	trace_fdb_delete(br, f);
315 
316 	if (test_bit(BR_FDB_STATIC, &f->flags))
317 		fdb_del_hw_addr(br, f->key.addr.addr);
318 
319 	hlist_del_init_rcu(&f->fdb_node);
320 	rhashtable_remove_fast(&br->fdb_hash_tbl, &f->rhnode,
321 			       br_fdb_rht_params);
322 	if (test_and_clear_bit(BR_FDB_DYNAMIC_LEARNED, &f->flags))
323 		atomic_dec(&br->fdb_n_learned);
324 	fdb_notify(br, f, RTM_DELNEIGH, swdev_notify);
325 	kfree_rcu(f, rcu);
326 }
327 
328 /* Delete a local entry if no other port had the same address.
329  *
330  * This function should only be called on entries with BR_FDB_LOCAL set,
331  * so even with BR_FDB_ADDED_BY_USER cleared we never need to increase
332  * the accounting for dynamically learned entries again.
333  */
334 static void fdb_delete_local(struct net_bridge *br,
335 			     const struct net_bridge_port *p,
336 			     struct net_bridge_fdb_entry *f)
337 {
338 	const unsigned char *addr = f->key.addr.addr;
339 	struct net_bridge_vlan_group *vg;
340 	const struct net_bridge_vlan *v;
341 	struct net_bridge_port *op;
342 	u16 vid = f->key.vlan_id;
343 
344 	/* Maybe another port has same hw addr? */
345 	list_for_each_entry(op, &br->port_list, list) {
346 		vg = nbp_vlan_group(op);
347 		if (op != p && ether_addr_equal(op->dev->dev_addr, addr) &&
348 		    (!vid || br_vlan_find(vg, vid))) {
349 			f->dst = op;
350 			clear_bit(BR_FDB_ADDED_BY_USER, &f->flags);
351 			return;
352 		}
353 	}
354 
355 	vg = br_vlan_group(br);
356 	v = br_vlan_find(vg, vid);
357 	/* Maybe bridge device has same hw addr? */
358 	if (p && ether_addr_equal(br->dev->dev_addr, addr) &&
359 	    (!vid || (v && br_vlan_should_use(v)))) {
360 		f->dst = NULL;
361 		clear_bit(BR_FDB_ADDED_BY_USER, &f->flags);
362 		return;
363 	}
364 
365 	fdb_delete(br, f, true);
366 }
367 
368 void br_fdb_find_delete_local(struct net_bridge *br,
369 			      const struct net_bridge_port *p,
370 			      const unsigned char *addr, u16 vid)
371 {
372 	struct net_bridge_fdb_entry *f;
373 
374 	spin_lock_bh(&br->hash_lock);
375 	f = br_fdb_find(br, addr, vid);
376 	if (f && test_bit(BR_FDB_LOCAL, &f->flags) &&
377 	    !test_bit(BR_FDB_ADDED_BY_USER, &f->flags) && f->dst == p)
378 		fdb_delete_local(br, p, f);
379 	spin_unlock_bh(&br->hash_lock);
380 }
381 
382 static struct net_bridge_fdb_entry *fdb_create(struct net_bridge *br,
383 					       struct net_bridge_port *source,
384 					       const unsigned char *addr,
385 					       __u16 vid,
386 					       unsigned long flags)
387 {
388 	bool learned = !test_bit(BR_FDB_ADDED_BY_USER, &flags) &&
389 		       !test_bit(BR_FDB_LOCAL, &flags);
390 	u32 max_learned = READ_ONCE(br->fdb_max_learned);
391 	struct net_bridge_fdb_entry *fdb;
392 	int err;
393 
394 	if (likely(learned)) {
395 		int n_learned = atomic_read(&br->fdb_n_learned);
396 
397 		if (unlikely(max_learned && n_learned >= max_learned))
398 			return NULL;
399 		__set_bit(BR_FDB_DYNAMIC_LEARNED, &flags);
400 	}
401 
402 	fdb = kmem_cache_alloc(br_fdb_cache, GFP_ATOMIC);
403 	if (!fdb)
404 		return NULL;
405 
406 	memcpy(fdb->key.addr.addr, addr, ETH_ALEN);
407 	WRITE_ONCE(fdb->dst, source);
408 	fdb->key.vlan_id = vid;
409 	fdb->flags = flags;
410 	fdb->updated = fdb->used = jiffies;
411 	err = rhashtable_lookup_insert_fast(&br->fdb_hash_tbl, &fdb->rhnode,
412 					    br_fdb_rht_params);
413 	if (err) {
414 		kmem_cache_free(br_fdb_cache, fdb);
415 		return NULL;
416 	}
417 
418 	if (likely(learned))
419 		atomic_inc(&br->fdb_n_learned);
420 
421 	hlist_add_head_rcu(&fdb->fdb_node, &br->fdb_list);
422 
423 	return fdb;
424 }
425 
426 static int fdb_add_local(struct net_bridge *br, struct net_bridge_port *source,
427 			 const unsigned char *addr, u16 vid)
428 {
429 	struct net_bridge_fdb_entry *fdb;
430 
431 	if (!is_valid_ether_addr(addr))
432 		return -EINVAL;
433 
434 	fdb = br_fdb_find(br, addr, vid);
435 	if (fdb) {
436 		/* it is okay to have multiple ports with same
437 		 * address, just use the first one.
438 		 */
439 		if (test_bit(BR_FDB_LOCAL, &fdb->flags))
440 			return 0;
441 		br_warn(br, "adding interface %s with same address as a received packet (addr:%pM, vlan:%u)\n",
442 			source ? source->dev->name : br->dev->name, addr, vid);
443 		fdb_delete(br, fdb, true);
444 	}
445 
446 	fdb = fdb_create(br, source, addr, vid,
447 			 BIT(BR_FDB_LOCAL) | BIT(BR_FDB_STATIC));
448 	if (!fdb)
449 		return -ENOMEM;
450 
451 	fdb_add_hw_addr(br, addr);
452 	fdb_notify(br, fdb, RTM_NEWNEIGH, true);
453 	return 0;
454 }
455 
456 void br_fdb_changeaddr(struct net_bridge_port *p, const unsigned char *newaddr)
457 {
458 	struct net_bridge_vlan_group *vg;
459 	struct net_bridge_fdb_entry *f;
460 	struct net_bridge *br = p->br;
461 	struct net_bridge_vlan *v;
462 	bool local_vlan_0;
463 
464 	local_vlan_0 = br_opt_get(br, BROPT_FDB_LOCAL_VLAN_0);
465 
466 	spin_lock_bh(&br->hash_lock);
467 	vg = nbp_vlan_group(p);
468 	hlist_for_each_entry(f, &br->fdb_list, fdb_node) {
469 		if (f->dst == p && test_bit(BR_FDB_LOCAL, &f->flags) &&
470 		    !test_bit(BR_FDB_ADDED_BY_USER, &f->flags)) {
471 			/* delete old one */
472 			fdb_delete_local(br, p, f);
473 
474 			/* if this port has no vlan information configured, or
475 			 * local entries are only kept on VLAN 0, we can safely
476 			 * be done at this point.
477 			 */
478 			if (!vg || !vg->num_vlans || local_vlan_0)
479 				goto insert;
480 		}
481 	}
482 
483 insert:
484 	/* insert new address,  may fail if invalid address or dup. */
485 	fdb_add_local(br, p, newaddr, 0);
486 
487 	if (!vg || !vg->num_vlans || local_vlan_0)
488 		goto done;
489 
490 	/* Now add entries for every VLAN configured on the port.
491 	 * This function runs under RTNL so the bitmap will not change
492 	 * from under us.
493 	 */
494 	list_for_each_entry(v, &vg->vlan_list, vlist)
495 		fdb_add_local(br, p, newaddr, v->vid);
496 
497 done:
498 	spin_unlock_bh(&br->hash_lock);
499 }
500 
501 void br_fdb_change_mac_address(struct net_bridge *br, const u8 *newaddr)
502 {
503 	struct net_bridge_vlan_group *vg;
504 	struct net_bridge_fdb_entry *f;
505 	struct net_bridge_vlan *v;
506 	bool local_vlan_0;
507 
508 	local_vlan_0 = br_opt_get(br, BROPT_FDB_LOCAL_VLAN_0);
509 
510 	spin_lock_bh(&br->hash_lock);
511 
512 	/* If old entry was unassociated with any port, then delete it. */
513 	f = br_fdb_find(br, br->dev->dev_addr, 0);
514 	if (f && test_bit(BR_FDB_LOCAL, &f->flags) &&
515 	    !f->dst && !test_bit(BR_FDB_ADDED_BY_USER, &f->flags))
516 		fdb_delete_local(br, NULL, f);
517 
518 	fdb_add_local(br, NULL, newaddr, 0);
519 	vg = br_vlan_group(br);
520 	if (!vg || !vg->num_vlans || local_vlan_0)
521 		goto out;
522 	/* Now remove and add entries for every VLAN configured on the
523 	 * bridge.  This function runs under RTNL so the bitmap will not
524 	 * change from under us.
525 	 */
526 	list_for_each_entry(v, &vg->vlan_list, vlist) {
527 		if (!br_vlan_should_use(v))
528 			continue;
529 		f = br_fdb_find(br, br->dev->dev_addr, v->vid);
530 		if (f && test_bit(BR_FDB_LOCAL, &f->flags) &&
531 		    !f->dst && !test_bit(BR_FDB_ADDED_BY_USER, &f->flags))
532 			fdb_delete_local(br, NULL, f);
533 		fdb_add_local(br, NULL, newaddr, v->vid);
534 	}
535 out:
536 	spin_unlock_bh(&br->hash_lock);
537 }
538 
539 void br_fdb_cleanup(struct work_struct *work)
540 {
541 	struct net_bridge *br = container_of(work, struct net_bridge,
542 					     gc_work.work);
543 	struct net_bridge_fdb_entry *f = NULL;
544 	unsigned long delay = hold_time(br);
545 	unsigned long work_delay = delay;
546 	unsigned long now = jiffies;
547 
548 	/* this part is tricky, in order to avoid blocking learning and
549 	 * consequently forwarding, we rely on rcu to delete objects with
550 	 * delayed freeing allowing us to continue traversing
551 	 */
552 	rcu_read_lock();
553 	hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
554 		unsigned long this_timer = f->updated + delay;
555 
556 		if (test_bit(BR_FDB_STATIC, &f->flags) ||
557 		    test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &f->flags)) {
558 			if (test_bit(BR_FDB_NOTIFY, &f->flags)) {
559 				if (time_after(this_timer, now))
560 					work_delay = min(work_delay,
561 							 this_timer - now);
562 				else if (!test_and_set_bit(BR_FDB_NOTIFY_INACTIVE,
563 							   &f->flags))
564 					fdb_notify(br, f, RTM_NEWNEIGH, false);
565 			}
566 			continue;
567 		}
568 
569 		if (time_after(this_timer, now)) {
570 			work_delay = min(work_delay, this_timer - now);
571 		} else {
572 			spin_lock_bh(&br->hash_lock);
573 			if (!hlist_unhashed(&f->fdb_node))
574 				fdb_delete(br, f, true);
575 			spin_unlock_bh(&br->hash_lock);
576 		}
577 	}
578 	rcu_read_unlock();
579 
580 	/* Cleanup minimum 10 milliseconds apart */
581 	work_delay = max_t(unsigned long, work_delay, msecs_to_jiffies(10));
582 	mod_delayed_work(system_long_wq, &br->gc_work, work_delay);
583 }
584 
585 static void br_fdb_delete_locals_per_vlan_port(struct net_bridge *br,
586 					       struct net_bridge_port *p)
587 {
588 	struct net_bridge_vlan_group *vg;
589 	struct net_bridge_vlan *v;
590 	struct net_device *dev;
591 
592 	if (p) {
593 		vg = nbp_vlan_group(p);
594 		dev = p->dev;
595 	} else {
596 		vg = br_vlan_group(br);
597 		dev = br->dev;
598 	}
599 
600 	list_for_each_entry(v, &vg->vlan_list, vlist)
601 		br_fdb_find_delete_local(br, p, dev->dev_addr, v->vid);
602 }
603 
604 static void br_fdb_delete_locals_per_vlan(struct net_bridge *br)
605 {
606 	struct net_bridge_port *p;
607 
608 	ASSERT_RTNL();
609 
610 	list_for_each_entry(p, &br->port_list, list)
611 		br_fdb_delete_locals_per_vlan_port(br, p);
612 
613 	br_fdb_delete_locals_per_vlan_port(br, NULL);
614 }
615 
616 static int br_fdb_insert_locals_per_vlan_port(struct net_bridge *br,
617 					      struct net_bridge_port *p,
618 					      struct netlink_ext_ack *extack)
619 {
620 	struct net_bridge_vlan_group *vg;
621 	struct net_bridge_vlan *v;
622 	struct net_device *dev;
623 	int err;
624 
625 	if (p) {
626 		vg = nbp_vlan_group(p);
627 		dev = p->dev;
628 	} else {
629 		vg = br_vlan_group(br);
630 		dev = br->dev;
631 	}
632 
633 	list_for_each_entry(v, &vg->vlan_list, vlist) {
634 		if (!br_vlan_should_use(v))
635 			continue;
636 
637 		err = br_fdb_add_local(br, p, dev->dev_addr, v->vid);
638 		if (err)
639 			return err;
640 	}
641 
642 	return 0;
643 }
644 
645 static int br_fdb_insert_locals_per_vlan(struct net_bridge *br,
646 					 struct netlink_ext_ack *extack)
647 {
648 	struct net_bridge_port *p;
649 	int err;
650 
651 	ASSERT_RTNL();
652 
653 	list_for_each_entry(p, &br->port_list, list) {
654 		err = br_fdb_insert_locals_per_vlan_port(br, p, extack);
655 		if (err)
656 			goto rollback;
657 	}
658 
659 	err = br_fdb_insert_locals_per_vlan_port(br, NULL, extack);
660 	if (err)
661 		goto rollback;
662 
663 	return 0;
664 
665 rollback:
666 	NL_SET_ERR_MSG_MOD(extack, "fdb_local_vlan_0 toggle: FDB entry insertion failed");
667 	br_fdb_delete_locals_per_vlan(br);
668 	return err;
669 }
670 
671 int br_fdb_toggle_local_vlan_0(struct net_bridge *br, bool on,
672 			       struct netlink_ext_ack *extack)
673 {
674 	if (!on)
675 		return br_fdb_insert_locals_per_vlan(br, extack);
676 
677 	br_fdb_delete_locals_per_vlan(br);
678 	return 0;
679 }
680 
681 static bool __fdb_flush_matches(const struct net_bridge *br,
682 				const struct net_bridge_fdb_entry *f,
683 				const struct net_bridge_fdb_flush_desc *desc)
684 {
685 	const struct net_bridge_port *dst = READ_ONCE(f->dst);
686 	int port_ifidx = dst ? dst->dev->ifindex : br->dev->ifindex;
687 
688 	if (desc->vlan_id && desc->vlan_id != f->key.vlan_id)
689 		return false;
690 	if (desc->port_ifindex && desc->port_ifindex != port_ifidx)
691 		return false;
692 	if (desc->flags_mask && (f->flags & desc->flags_mask) != desc->flags)
693 		return false;
694 
695 	return true;
696 }
697 
698 /* Flush forwarding database entries matching the description */
699 void br_fdb_flush(struct net_bridge *br,
700 		  const struct net_bridge_fdb_flush_desc *desc)
701 {
702 	struct net_bridge_fdb_entry *f;
703 
704 	rcu_read_lock();
705 	hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
706 		if (!__fdb_flush_matches(br, f, desc))
707 			continue;
708 
709 		spin_lock_bh(&br->hash_lock);
710 		if (!hlist_unhashed(&f->fdb_node))
711 			fdb_delete(br, f, true);
712 		spin_unlock_bh(&br->hash_lock);
713 	}
714 	rcu_read_unlock();
715 }
716 
717 static unsigned long __ndm_state_to_fdb_flags(u16 ndm_state)
718 {
719 	unsigned long flags = 0;
720 
721 	if (ndm_state & NUD_PERMANENT)
722 		__set_bit(BR_FDB_LOCAL, &flags);
723 	if (ndm_state & NUD_NOARP)
724 		__set_bit(BR_FDB_STATIC, &flags);
725 
726 	return flags;
727 }
728 
729 static unsigned long __ndm_flags_to_fdb_flags(u8 ndm_flags)
730 {
731 	unsigned long flags = 0;
732 
733 	if (ndm_flags & NTF_USE)
734 		__set_bit(BR_FDB_ADDED_BY_USER, &flags);
735 	if (ndm_flags & NTF_EXT_LEARNED)
736 		__set_bit(BR_FDB_ADDED_BY_EXT_LEARN, &flags);
737 	if (ndm_flags & NTF_OFFLOADED)
738 		__set_bit(BR_FDB_OFFLOADED, &flags);
739 	if (ndm_flags & NTF_STICKY)
740 		__set_bit(BR_FDB_STICKY, &flags);
741 
742 	return flags;
743 }
744 
745 static int __fdb_flush_validate_ifindex(const struct net_bridge *br,
746 					int ifindex,
747 					struct netlink_ext_ack *extack)
748 {
749 	const struct net_device *dev;
750 
751 	dev = __dev_get_by_index(dev_net(br->dev), ifindex);
752 	if (!dev) {
753 		NL_SET_ERR_MSG_MOD(extack, "Unknown flush device ifindex");
754 		return -ENODEV;
755 	}
756 	if (!netif_is_bridge_master(dev) && !netif_is_bridge_port(dev)) {
757 		NL_SET_ERR_MSG_MOD(extack, "Flush device is not a bridge or bridge port");
758 		return -EINVAL;
759 	}
760 	if (netif_is_bridge_master(dev) && dev != br->dev) {
761 		NL_SET_ERR_MSG_MOD(extack,
762 				   "Flush bridge device does not match target bridge device");
763 		return -EINVAL;
764 	}
765 	if (netif_is_bridge_port(dev)) {
766 		struct net_bridge_port *p = br_port_get_rtnl(dev);
767 
768 		if (p->br != br) {
769 			NL_SET_ERR_MSG_MOD(extack, "Port belongs to a different bridge device");
770 			return -EINVAL;
771 		}
772 	}
773 
774 	return 0;
775 }
776 
777 static const struct nla_policy br_fdb_del_bulk_policy[NDA_MAX + 1] = {
778 	[NDA_VLAN]	= NLA_POLICY_RANGE(NLA_U16, 1, VLAN_N_VID - 2),
779 	[NDA_IFINDEX]	= NLA_POLICY_MIN(NLA_S32, 1),
780 	[NDA_NDM_STATE_MASK]	= { .type = NLA_U16 },
781 	[NDA_NDM_FLAGS_MASK]	= { .type = NLA_U8 },
782 };
783 
784 int br_fdb_delete_bulk(struct nlmsghdr *nlh, struct net_device *dev,
785 		       struct netlink_ext_ack *extack)
786 {
787 	struct net_bridge_fdb_flush_desc desc = {};
788 	struct ndmsg *ndm = nlmsg_data(nlh);
789 	struct net_bridge_port *p = NULL;
790 	struct nlattr *tb[NDA_MAX + 1];
791 	struct net_bridge *br;
792 	u8 ndm_flags;
793 	int err;
794 
795 	ndm_flags = ndm->ndm_flags & ~FDB_FLUSH_IGNORED_NDM_FLAGS;
796 
797 	err = nlmsg_parse(nlh, sizeof(*ndm), tb, NDA_MAX,
798 			  br_fdb_del_bulk_policy, extack);
799 	if (err)
800 		return err;
801 
802 	if (netif_is_bridge_master(dev)) {
803 		br = netdev_priv(dev);
804 	} else {
805 		p = br_port_get_rtnl(dev);
806 		if (!p) {
807 			NL_SET_ERR_MSG_MOD(extack, "Device is not a bridge port");
808 			return -EINVAL;
809 		}
810 		br = p->br;
811 	}
812 
813 	if (tb[NDA_VLAN])
814 		desc.vlan_id = nla_get_u16(tb[NDA_VLAN]);
815 
816 	if (ndm_flags & ~FDB_FLUSH_ALLOWED_NDM_FLAGS) {
817 		NL_SET_ERR_MSG(extack, "Unsupported fdb flush ndm flag bits set");
818 		return -EINVAL;
819 	}
820 	if (ndm->ndm_state & ~FDB_FLUSH_ALLOWED_NDM_STATES) {
821 		NL_SET_ERR_MSG(extack, "Unsupported fdb flush ndm state bits set");
822 		return -EINVAL;
823 	}
824 
825 	desc.flags |= __ndm_state_to_fdb_flags(ndm->ndm_state);
826 	desc.flags |= __ndm_flags_to_fdb_flags(ndm_flags);
827 	if (tb[NDA_NDM_STATE_MASK]) {
828 		u16 ndm_state_mask = nla_get_u16(tb[NDA_NDM_STATE_MASK]);
829 
830 		desc.flags_mask |= __ndm_state_to_fdb_flags(ndm_state_mask);
831 	}
832 	if (tb[NDA_NDM_FLAGS_MASK]) {
833 		u8 ndm_flags_mask = nla_get_u8(tb[NDA_NDM_FLAGS_MASK]);
834 
835 		desc.flags_mask |= __ndm_flags_to_fdb_flags(ndm_flags_mask);
836 	}
837 	if (tb[NDA_IFINDEX]) {
838 		int ifidx = nla_get_s32(tb[NDA_IFINDEX]);
839 
840 		err = __fdb_flush_validate_ifindex(br, ifidx, extack);
841 		if (err)
842 			return err;
843 		desc.port_ifindex = ifidx;
844 	} else if (p) {
845 		/* flush was invoked with port device and NTF_MASTER */
846 		desc.port_ifindex = p->dev->ifindex;
847 	}
848 
849 	br_debug(br, "flushing port ifindex: %d vlan id: %u flags: 0x%lx flags mask: 0x%lx\n",
850 		 desc.port_ifindex, desc.vlan_id, desc.flags, desc.flags_mask);
851 
852 	br_fdb_flush(br, &desc);
853 
854 	return 0;
855 }
856 
857 /* Flush all entries referring to a specific port.
858  * if do_all is set also flush static entries
859  * if vid is set delete all entries that match the vlan_id
860  */
861 void br_fdb_delete_by_port(struct net_bridge *br,
862 			   const struct net_bridge_port *p,
863 			   u16 vid,
864 			   int do_all)
865 {
866 	struct net_bridge_fdb_entry *f;
867 	struct hlist_node *tmp;
868 
869 	spin_lock_bh(&br->hash_lock);
870 	hlist_for_each_entry_safe(f, tmp, &br->fdb_list, fdb_node) {
871 		if (f->dst != p)
872 			continue;
873 
874 		if (!do_all)
875 			if (test_bit(BR_FDB_STATIC, &f->flags) ||
876 			    (test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &f->flags) &&
877 			     !test_bit(BR_FDB_OFFLOADED, &f->flags)) ||
878 			    (vid && f->key.vlan_id != vid))
879 				continue;
880 
881 		if (test_bit(BR_FDB_LOCAL, &f->flags))
882 			fdb_delete_local(br, p, f);
883 		else
884 			fdb_delete(br, f, true);
885 	}
886 	spin_unlock_bh(&br->hash_lock);
887 }
888 
889 #if IS_ENABLED(CONFIG_ATM_LANE)
890 /* Interface used by ATM LANE hook to test
891  * if an addr is on some other bridge port */
892 int br_fdb_test_addr(struct net_device *dev, unsigned char *addr)
893 {
894 	struct net_bridge_fdb_entry *fdb;
895 	struct net_bridge_port *port;
896 	int ret;
897 
898 	rcu_read_lock();
899 	port = br_port_get_rcu(dev);
900 	if (!port)
901 		ret = 0;
902 	else {
903 		const struct net_bridge_port *dst = NULL;
904 
905 		fdb = br_fdb_find_rcu(port->br, addr, 0);
906 		if (fdb)
907 			dst = READ_ONCE(fdb->dst);
908 
909 		ret = dst && dst->dev != dev &&
910 		      dst->state == BR_STATE_FORWARDING;
911 	}
912 	rcu_read_unlock();
913 
914 	return ret;
915 }
916 #endif /* CONFIG_ATM_LANE */
917 
918 /*
919  * Fill buffer with forwarding table records in
920  * the API format.
921  */
922 int br_fdb_fillbuf(struct net_bridge *br, void *buf,
923 		   unsigned long maxnum, unsigned long skip)
924 {
925 	struct net_bridge_fdb_entry *f;
926 	struct __fdb_entry *fe = buf;
927 	int num = 0;
928 
929 	memset(buf, 0, maxnum*sizeof(struct __fdb_entry));
930 
931 	rcu_read_lock();
932 	hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
933 		if (num >= maxnum)
934 			break;
935 
936 		if (has_expired(br, f))
937 			continue;
938 
939 		/* ignore pseudo entry for local MAC address */
940 		if (!f->dst)
941 			continue;
942 
943 		if (skip) {
944 			--skip;
945 			continue;
946 		}
947 
948 		/* convert from internal format to API */
949 		memcpy(fe->mac_addr, f->key.addr.addr, ETH_ALEN);
950 
951 		/* due to ABI compat need to split into hi/lo */
952 		fe->port_no = f->dst->port_no;
953 		fe->port_hi = f->dst->port_no >> 8;
954 
955 		fe->is_local = test_bit(BR_FDB_LOCAL, &f->flags);
956 		if (!test_bit(BR_FDB_STATIC, &f->flags))
957 			fe->ageing_timer_value = jiffies_delta_to_clock_t(jiffies - f->updated);
958 		++fe;
959 		++num;
960 	}
961 	rcu_read_unlock();
962 
963 	return num;
964 }
965 
966 /* Add entry for local address of interface */
967 int br_fdb_add_local(struct net_bridge *br, struct net_bridge_port *source,
968 		     const unsigned char *addr, u16 vid)
969 {
970 	int ret;
971 
972 	spin_lock_bh(&br->hash_lock);
973 	ret = fdb_add_local(br, source, addr, vid);
974 	spin_unlock_bh(&br->hash_lock);
975 	return ret;
976 }
977 
978 /* returns true if the fdb was modified */
979 static bool __fdb_mark_active(struct net_bridge_fdb_entry *fdb)
980 {
981 	return !!(test_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags) &&
982 		  test_and_clear_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags));
983 }
984 
985 void br_fdb_update(struct net_bridge *br, struct net_bridge_port *source,
986 		   const unsigned char *addr, u16 vid, unsigned long flags)
987 {
988 	struct net_bridge_fdb_entry *fdb;
989 
990 	/* some users want to always flood. */
991 	if (hold_time(br) == 0)
992 		return;
993 
994 	fdb = fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
995 	if (likely(fdb)) {
996 		/* attempt to update an entry for a local interface */
997 		if (unlikely(test_bit(BR_FDB_LOCAL, &fdb->flags))) {
998 			if (net_ratelimit())
999 				br_warn(br, "received packet on %s with own address as source address (addr:%pM, vlan:%u)\n",
1000 					source->dev->name, addr, vid);
1001 		} else {
1002 			unsigned long now = jiffies;
1003 			bool fdb_modified = false;
1004 
1005 			if (now != fdb->updated) {
1006 				fdb->updated = now;
1007 				fdb_modified = __fdb_mark_active(fdb);
1008 			}
1009 
1010 			/* fastpath: update of existing entry */
1011 			if (unlikely(source != READ_ONCE(fdb->dst) &&
1012 				     !test_bit(BR_FDB_STICKY, &fdb->flags))) {
1013 				br_switchdev_fdb_notify(br, fdb, RTM_DELNEIGH);
1014 				WRITE_ONCE(fdb->dst, source);
1015 				fdb_modified = true;
1016 				/* Take over HW learned entry */
1017 				if (unlikely(test_bit(BR_FDB_ADDED_BY_EXT_LEARN,
1018 						      &fdb->flags)))
1019 					clear_bit(BR_FDB_ADDED_BY_EXT_LEARN,
1020 						  &fdb->flags);
1021 				/* Clear locked flag when roaming to an
1022 				 * unlocked port.
1023 				 */
1024 				if (unlikely(test_bit(BR_FDB_LOCKED, &fdb->flags)))
1025 					clear_bit(BR_FDB_LOCKED, &fdb->flags);
1026 			}
1027 
1028 			if (unlikely(test_bit(BR_FDB_ADDED_BY_USER, &flags))) {
1029 				set_bit(BR_FDB_ADDED_BY_USER, &fdb->flags);
1030 				if (test_and_clear_bit(BR_FDB_DYNAMIC_LEARNED,
1031 						       &fdb->flags))
1032 					atomic_dec(&br->fdb_n_learned);
1033 			}
1034 			if (unlikely(fdb_modified)) {
1035 				trace_br_fdb_update(br, source, addr, vid, flags);
1036 				fdb_notify(br, fdb, RTM_NEWNEIGH, true);
1037 			}
1038 		}
1039 	} else {
1040 		spin_lock(&br->hash_lock);
1041 		fdb = fdb_create(br, source, addr, vid, flags);
1042 		if (fdb) {
1043 			trace_br_fdb_update(br, source, addr, vid, flags);
1044 			fdb_notify(br, fdb, RTM_NEWNEIGH, true);
1045 		}
1046 		/* else  we lose race and someone else inserts
1047 		 * it first, don't bother updating
1048 		 */
1049 		spin_unlock(&br->hash_lock);
1050 	}
1051 }
1052 
1053 /* Dump information about entries, in response to GETNEIGH */
1054 int br_fdb_dump(struct sk_buff *skb,
1055 		struct netlink_callback *cb,
1056 		struct net_device *dev,
1057 		struct net_device *filter_dev,
1058 		int *idx)
1059 {
1060 	struct ndo_fdb_dump_context *ctx = (void *)cb->ctx;
1061 	struct net_bridge *br = netdev_priv(dev);
1062 	struct net_bridge_fdb_entry *f;
1063 	int err = 0;
1064 
1065 	if (!netif_is_bridge_master(dev))
1066 		return err;
1067 
1068 	if (!filter_dev) {
1069 		err = ndo_dflt_fdb_dump(skb, cb, dev, NULL, idx);
1070 		if (err < 0)
1071 			return err;
1072 	}
1073 
1074 	rcu_read_lock();
1075 	hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
1076 		if (*idx < ctx->fdb_idx)
1077 			goto skip;
1078 		if (filter_dev && (!f->dst || f->dst->dev != filter_dev)) {
1079 			if (filter_dev != dev)
1080 				goto skip;
1081 			/* !f->dst is a special case for bridge
1082 			 * It means the MAC belongs to the bridge
1083 			 * Therefore need a little more filtering
1084 			 * we only want to dump the !f->dst case
1085 			 */
1086 			if (f->dst)
1087 				goto skip;
1088 		}
1089 		if (!filter_dev && f->dst)
1090 			goto skip;
1091 
1092 		err = fdb_fill_info(skb, br, f,
1093 				    NETLINK_CB(cb->skb).portid,
1094 				    cb->nlh->nlmsg_seq,
1095 				    RTM_NEWNEIGH,
1096 				    NLM_F_MULTI);
1097 		if (err < 0)
1098 			break;
1099 skip:
1100 		*idx += 1;
1101 	}
1102 	rcu_read_unlock();
1103 
1104 	return err;
1105 }
1106 
1107 int br_fdb_get(struct sk_buff *skb,
1108 	       struct nlattr *tb[],
1109 	       struct net_device *dev,
1110 	       const unsigned char *addr,
1111 	       u16 vid, u32 portid, u32 seq,
1112 	       struct netlink_ext_ack *extack)
1113 {
1114 	struct net_bridge *br = netdev_priv(dev);
1115 	struct net_bridge_fdb_entry *f;
1116 	int err = 0;
1117 
1118 	rcu_read_lock();
1119 	f = br_fdb_find_rcu(br, addr, vid);
1120 	if (!f) {
1121 		NL_SET_ERR_MSG(extack, "Fdb entry not found");
1122 		err = -ENOENT;
1123 		goto errout;
1124 	}
1125 
1126 	err = fdb_fill_info(skb, br, f, portid, seq,
1127 			    RTM_NEWNEIGH, 0);
1128 errout:
1129 	rcu_read_unlock();
1130 	return err;
1131 }
1132 
1133 /* returns true if the fdb is modified */
1134 static bool fdb_handle_notify(struct net_bridge_fdb_entry *fdb, u8 notify)
1135 {
1136 	bool modified = false;
1137 
1138 	/* allow to mark an entry as inactive, usually done on creation */
1139 	if ((notify & FDB_NOTIFY_INACTIVE_BIT) &&
1140 	    !test_and_set_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags))
1141 		modified = true;
1142 
1143 	if ((notify & FDB_NOTIFY_BIT) &&
1144 	    !test_and_set_bit(BR_FDB_NOTIFY, &fdb->flags)) {
1145 		/* enabled activity tracking */
1146 		modified = true;
1147 	} else if (!(notify & FDB_NOTIFY_BIT) &&
1148 		   test_and_clear_bit(BR_FDB_NOTIFY, &fdb->flags)) {
1149 		/* disabled activity tracking, clear notify state */
1150 		clear_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags);
1151 		modified = true;
1152 	}
1153 
1154 	return modified;
1155 }
1156 
1157 /* Update (create or replace) forwarding database entry */
1158 static int fdb_add_entry(struct net_bridge *br, struct net_bridge_port *source,
1159 			 const u8 *addr, struct ndmsg *ndm, u16 flags, u16 vid,
1160 			 struct nlattr *nfea_tb[])
1161 {
1162 	bool is_sticky = !!(ndm->ndm_flags & NTF_STICKY);
1163 	bool refresh = !nfea_tb[NFEA_DONT_REFRESH];
1164 	struct net_bridge_fdb_entry *fdb;
1165 	u16 state = ndm->ndm_state;
1166 	bool modified = false;
1167 	u8 notify = 0;
1168 
1169 	/* If the port cannot learn allow only local and static entries */
1170 	if (source && !(state & NUD_PERMANENT) && !(state & NUD_NOARP) &&
1171 	    !(source->state == BR_STATE_LEARNING ||
1172 	      source->state == BR_STATE_FORWARDING))
1173 		return -EPERM;
1174 
1175 	if (!source && !(state & NUD_PERMANENT)) {
1176 		pr_info("bridge: RTM_NEWNEIGH %s without NUD_PERMANENT\n",
1177 			br->dev->name);
1178 		return -EINVAL;
1179 	}
1180 
1181 	if (is_sticky && (state & NUD_PERMANENT))
1182 		return -EINVAL;
1183 
1184 	if (nfea_tb[NFEA_ACTIVITY_NOTIFY]) {
1185 		notify = nla_get_u8(nfea_tb[NFEA_ACTIVITY_NOTIFY]);
1186 		if ((notify & ~BR_FDB_NOTIFY_SETTABLE_BITS) ||
1187 		    (notify & BR_FDB_NOTIFY_SETTABLE_BITS) == FDB_NOTIFY_INACTIVE_BIT)
1188 			return -EINVAL;
1189 	}
1190 
1191 	fdb = br_fdb_find(br, addr, vid);
1192 	if (fdb == NULL) {
1193 		if (!(flags & NLM_F_CREATE))
1194 			return -ENOENT;
1195 
1196 		fdb = fdb_create(br, source, addr, vid,
1197 				 BIT(BR_FDB_ADDED_BY_USER));
1198 		if (!fdb)
1199 			return -ENOMEM;
1200 
1201 		modified = true;
1202 	} else {
1203 		if (flags & NLM_F_EXCL)
1204 			return -EEXIST;
1205 
1206 		if (READ_ONCE(fdb->dst) != source) {
1207 			WRITE_ONCE(fdb->dst, source);
1208 			modified = true;
1209 		}
1210 
1211 		set_bit(BR_FDB_ADDED_BY_USER, &fdb->flags);
1212 		if (test_and_clear_bit(BR_FDB_DYNAMIC_LEARNED, &fdb->flags))
1213 			atomic_dec(&br->fdb_n_learned);
1214 	}
1215 
1216 	if (fdb_to_nud(br, fdb) != state) {
1217 		if (state & NUD_PERMANENT) {
1218 			set_bit(BR_FDB_LOCAL, &fdb->flags);
1219 			if (!test_and_set_bit(BR_FDB_STATIC, &fdb->flags))
1220 				fdb_add_hw_addr(br, addr);
1221 		} else if (state & NUD_NOARP) {
1222 			clear_bit(BR_FDB_LOCAL, &fdb->flags);
1223 			if (!test_and_set_bit(BR_FDB_STATIC, &fdb->flags))
1224 				fdb_add_hw_addr(br, addr);
1225 		} else {
1226 			clear_bit(BR_FDB_LOCAL, &fdb->flags);
1227 			if (test_and_clear_bit(BR_FDB_STATIC, &fdb->flags))
1228 				fdb_del_hw_addr(br, addr);
1229 		}
1230 
1231 		modified = true;
1232 	}
1233 
1234 	if (is_sticky != test_bit(BR_FDB_STICKY, &fdb->flags)) {
1235 		change_bit(BR_FDB_STICKY, &fdb->flags);
1236 		modified = true;
1237 	}
1238 
1239 	if (test_and_clear_bit(BR_FDB_LOCKED, &fdb->flags))
1240 		modified = true;
1241 
1242 	if (fdb_handle_notify(fdb, notify))
1243 		modified = true;
1244 
1245 	fdb->used = jiffies;
1246 	if (modified) {
1247 		if (refresh)
1248 			fdb->updated = jiffies;
1249 		fdb_notify(br, fdb, RTM_NEWNEIGH, true);
1250 	}
1251 
1252 	return 0;
1253 }
1254 
1255 static int __br_fdb_add(struct ndmsg *ndm, struct net_bridge *br,
1256 			struct net_bridge_port *p, const unsigned char *addr,
1257 			u16 nlh_flags, u16 vid, struct nlattr *nfea_tb[],
1258 			bool *notified, struct netlink_ext_ack *extack)
1259 {
1260 	int err = 0;
1261 
1262 	if (ndm->ndm_flags & NTF_USE) {
1263 		if (!p) {
1264 			pr_info("bridge: RTM_NEWNEIGH %s with NTF_USE is not supported\n",
1265 				br->dev->name);
1266 			return -EINVAL;
1267 		}
1268 		if (!nbp_state_should_learn(p))
1269 			return 0;
1270 
1271 		local_bh_disable();
1272 		rcu_read_lock();
1273 		br_fdb_update(br, p, addr, vid, BIT(BR_FDB_ADDED_BY_USER));
1274 		rcu_read_unlock();
1275 		local_bh_enable();
1276 	} else if (ndm->ndm_flags & NTF_EXT_LEARNED) {
1277 		if (!p && !(ndm->ndm_state & NUD_PERMANENT)) {
1278 			NL_SET_ERR_MSG_MOD(extack,
1279 					   "FDB entry towards bridge must be permanent");
1280 			return -EINVAL;
1281 		}
1282 		err = br_fdb_external_learn_add(br, p, addr, vid, false, true);
1283 	} else {
1284 		spin_lock_bh(&br->hash_lock);
1285 		err = fdb_add_entry(br, p, addr, ndm, nlh_flags, vid, nfea_tb);
1286 		spin_unlock_bh(&br->hash_lock);
1287 	}
1288 
1289 	if (!err)
1290 		*notified = true;
1291 	return err;
1292 }
1293 
1294 static const struct nla_policy br_nda_fdb_pol[NFEA_MAX + 1] = {
1295 	[NFEA_ACTIVITY_NOTIFY]	= { .type = NLA_U8 },
1296 	[NFEA_DONT_REFRESH]	= { .type = NLA_FLAG },
1297 };
1298 
1299 /* Add new permanent fdb entry with RTM_NEWNEIGH */
1300 int br_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
1301 	       struct net_device *dev,
1302 	       const unsigned char *addr, u16 vid, u16 nlh_flags,
1303 	       bool *notified, struct netlink_ext_ack *extack)
1304 {
1305 	struct nlattr *nfea_tb[NFEA_MAX + 1], *attr;
1306 	struct net_bridge_vlan_group *vg;
1307 	struct net_bridge_port *p = NULL;
1308 	struct net_bridge_vlan *v;
1309 	struct net_bridge *br = NULL;
1310 	u32 ext_flags = 0;
1311 	int err = 0;
1312 
1313 	trace_br_fdb_add(ndm, dev, addr, vid, nlh_flags);
1314 
1315 	if (!(ndm->ndm_state & (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE))) {
1316 		pr_info("bridge: RTM_NEWNEIGH with invalid state %#x\n", ndm->ndm_state);
1317 		return -EINVAL;
1318 	}
1319 
1320 	if (is_zero_ether_addr(addr)) {
1321 		pr_info("bridge: RTM_NEWNEIGH with invalid ether address\n");
1322 		return -EINVAL;
1323 	}
1324 
1325 	if (netif_is_bridge_master(dev)) {
1326 		br = netdev_priv(dev);
1327 		vg = br_vlan_group(br);
1328 	} else {
1329 		p = br_port_get_rtnl(dev);
1330 		if (!p) {
1331 			pr_info("bridge: RTM_NEWNEIGH %s not a bridge port\n",
1332 				dev->name);
1333 			return -EINVAL;
1334 		}
1335 		br = p->br;
1336 		vg = nbp_vlan_group(p);
1337 	}
1338 
1339 	if (tb[NDA_FLAGS_EXT])
1340 		ext_flags = nla_get_u32(tb[NDA_FLAGS_EXT]);
1341 
1342 	if (ext_flags & NTF_EXT_LOCKED) {
1343 		NL_SET_ERR_MSG_MOD(extack, "Cannot add FDB entry with \"locked\" flag set");
1344 		return -EINVAL;
1345 	}
1346 
1347 	if (tb[NDA_FDB_EXT_ATTRS]) {
1348 		attr = tb[NDA_FDB_EXT_ATTRS];
1349 		err = nla_parse_nested(nfea_tb, NFEA_MAX, attr,
1350 				       br_nda_fdb_pol, extack);
1351 		if (err)
1352 			return err;
1353 	} else {
1354 		memset(nfea_tb, 0, sizeof(struct nlattr *) * (NFEA_MAX + 1));
1355 	}
1356 
1357 	if (vid) {
1358 		v = br_vlan_find(vg, vid);
1359 		if (!v || !br_vlan_should_use(v)) {
1360 			pr_info("bridge: RTM_NEWNEIGH with unconfigured vlan %d on %s\n", vid, dev->name);
1361 			return -EINVAL;
1362 		}
1363 
1364 		/* VID was specified, so use it. */
1365 		err = __br_fdb_add(ndm, br, p, addr, nlh_flags, vid, nfea_tb,
1366 				   notified, extack);
1367 	} else {
1368 		err = __br_fdb_add(ndm, br, p, addr, nlh_flags, 0, nfea_tb,
1369 				   notified, extack);
1370 		if (err || !vg || !vg->num_vlans)
1371 			goto out;
1372 
1373 		/* We have vlans configured on this port and user didn't
1374 		 * specify a VLAN.  To be nice, add/update entry for every
1375 		 * vlan on this port.
1376 		 */
1377 		list_for_each_entry(v, &vg->vlan_list, vlist) {
1378 			if (!br_vlan_should_use(v))
1379 				continue;
1380 			err = __br_fdb_add(ndm, br, p, addr, nlh_flags, v->vid,
1381 					   nfea_tb, notified, extack);
1382 			if (err)
1383 				goto out;
1384 		}
1385 	}
1386 
1387 out:
1388 	return err;
1389 }
1390 
1391 static int fdb_delete_by_addr_and_port(struct net_bridge *br,
1392 				       const struct net_bridge_port *p,
1393 				       const u8 *addr, u16 vlan, bool *notified)
1394 {
1395 	struct net_bridge_fdb_entry *fdb;
1396 
1397 	fdb = br_fdb_find(br, addr, vlan);
1398 	if (!fdb || READ_ONCE(fdb->dst) != p)
1399 		return -ENOENT;
1400 
1401 	fdb_delete(br, fdb, true);
1402 	*notified = true;
1403 
1404 	return 0;
1405 }
1406 
1407 static int __br_fdb_delete(struct net_bridge *br,
1408 			   const struct net_bridge_port *p,
1409 			   const unsigned char *addr, u16 vid, bool *notified)
1410 {
1411 	int err;
1412 
1413 	spin_lock_bh(&br->hash_lock);
1414 	err = fdb_delete_by_addr_and_port(br, p, addr, vid, notified);
1415 	spin_unlock_bh(&br->hash_lock);
1416 
1417 	return err;
1418 }
1419 
1420 /* Remove neighbor entry with RTM_DELNEIGH */
1421 int br_fdb_delete(struct ndmsg *ndm, struct nlattr *tb[],
1422 		  struct net_device *dev,
1423 		  const unsigned char *addr, u16 vid, bool *notified,
1424 		  struct netlink_ext_ack *extack)
1425 {
1426 	struct net_bridge_vlan_group *vg;
1427 	struct net_bridge_port *p = NULL;
1428 	struct net_bridge *br;
1429 	int err;
1430 
1431 	if (netif_is_bridge_master(dev)) {
1432 		br = netdev_priv(dev);
1433 		vg = br_vlan_group(br);
1434 	} else {
1435 		p = br_port_get_rtnl(dev);
1436 		if (!p) {
1437 			pr_info("bridge: RTM_DELNEIGH %s not a bridge port\n",
1438 				dev->name);
1439 			return -EINVAL;
1440 		}
1441 		vg = nbp_vlan_group(p);
1442 		br = p->br;
1443 	}
1444 
1445 	if (vid) {
1446 		err = __br_fdb_delete(br, p, addr, vid, notified);
1447 	} else {
1448 		struct net_bridge_vlan *v;
1449 
1450 		err = -ENOENT;
1451 		err &= __br_fdb_delete(br, p, addr, 0, notified);
1452 		if (!vg || !vg->num_vlans)
1453 			return err;
1454 
1455 		list_for_each_entry(v, &vg->vlan_list, vlist) {
1456 			if (!br_vlan_should_use(v))
1457 				continue;
1458 			err &= __br_fdb_delete(br, p, addr, v->vid, notified);
1459 		}
1460 	}
1461 
1462 	return err;
1463 }
1464 
1465 int br_fdb_sync_static(struct net_bridge *br, struct net_bridge_port *p)
1466 {
1467 	struct net_bridge_fdb_entry *f, *tmp;
1468 	int err = 0;
1469 
1470 	ASSERT_RTNL();
1471 
1472 	/* the key here is that static entries change only under rtnl */
1473 	rcu_read_lock();
1474 	hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
1475 		/* We only care for static entries */
1476 		if (!test_bit(BR_FDB_STATIC, &f->flags))
1477 			continue;
1478 		err = dev_uc_add(p->dev, f->key.addr.addr);
1479 		if (err)
1480 			goto rollback;
1481 	}
1482 done:
1483 	rcu_read_unlock();
1484 
1485 	return err;
1486 
1487 rollback:
1488 	hlist_for_each_entry_rcu(tmp, &br->fdb_list, fdb_node) {
1489 		/* We only care for static entries */
1490 		if (!test_bit(BR_FDB_STATIC, &tmp->flags))
1491 			continue;
1492 		if (tmp == f)
1493 			break;
1494 		dev_uc_del(p->dev, tmp->key.addr.addr);
1495 	}
1496 
1497 	goto done;
1498 }
1499 
1500 void br_fdb_unsync_static(struct net_bridge *br, struct net_bridge_port *p)
1501 {
1502 	struct net_bridge_fdb_entry *f;
1503 
1504 	ASSERT_RTNL();
1505 
1506 	rcu_read_lock();
1507 	hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
1508 		/* We only care for static entries */
1509 		if (!test_bit(BR_FDB_STATIC, &f->flags))
1510 			continue;
1511 
1512 		dev_uc_del(p->dev, f->key.addr.addr);
1513 	}
1514 	rcu_read_unlock();
1515 }
1516 
1517 int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p,
1518 			      const unsigned char *addr, u16 vid, bool locked,
1519 			      bool swdev_notify)
1520 {
1521 	struct net_bridge_fdb_entry *fdb;
1522 	bool modified = false;
1523 	int err = 0;
1524 
1525 	trace_br_fdb_external_learn_add(br, p, addr, vid);
1526 
1527 	if (locked && (!p || !(p->flags & BR_PORT_MAB)))
1528 		return -EINVAL;
1529 
1530 	spin_lock_bh(&br->hash_lock);
1531 
1532 	fdb = br_fdb_find(br, addr, vid);
1533 	if (!fdb) {
1534 		unsigned long flags = BIT(BR_FDB_ADDED_BY_EXT_LEARN);
1535 
1536 		if (swdev_notify)
1537 			flags |= BIT(BR_FDB_ADDED_BY_USER);
1538 
1539 		if (!p)
1540 			flags |= BIT(BR_FDB_LOCAL);
1541 
1542 		if (locked)
1543 			flags |= BIT(BR_FDB_LOCKED);
1544 
1545 		fdb = fdb_create(br, p, addr, vid, flags);
1546 		if (!fdb) {
1547 			err = -ENOMEM;
1548 			goto err_unlock;
1549 		}
1550 		fdb_notify(br, fdb, RTM_NEWNEIGH, swdev_notify);
1551 	} else {
1552 		if (locked &&
1553 		    (!test_bit(BR_FDB_LOCKED, &fdb->flags) ||
1554 		     READ_ONCE(fdb->dst) != p)) {
1555 			err = -EINVAL;
1556 			goto err_unlock;
1557 		}
1558 
1559 		fdb->updated = jiffies;
1560 
1561 		if (READ_ONCE(fdb->dst) != p) {
1562 			WRITE_ONCE(fdb->dst, p);
1563 			modified = true;
1564 		}
1565 
1566 		if (test_and_set_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags)) {
1567 			/* Refresh entry */
1568 			fdb->used = jiffies;
1569 		} else {
1570 			modified = true;
1571 		}
1572 
1573 		if (locked != test_bit(BR_FDB_LOCKED, &fdb->flags)) {
1574 			change_bit(BR_FDB_LOCKED, &fdb->flags);
1575 			modified = true;
1576 		}
1577 
1578 		if (swdev_notify)
1579 			set_bit(BR_FDB_ADDED_BY_USER, &fdb->flags);
1580 
1581 		if (!p)
1582 			set_bit(BR_FDB_LOCAL, &fdb->flags);
1583 
1584 		if ((swdev_notify || !p) &&
1585 		    test_and_clear_bit(BR_FDB_DYNAMIC_LEARNED, &fdb->flags))
1586 			atomic_dec(&br->fdb_n_learned);
1587 
1588 		if (modified)
1589 			fdb_notify(br, fdb, RTM_NEWNEIGH, swdev_notify);
1590 	}
1591 
1592 err_unlock:
1593 	spin_unlock_bh(&br->hash_lock);
1594 
1595 	return err;
1596 }
1597 
1598 int br_fdb_external_learn_del(struct net_bridge *br, struct net_bridge_port *p,
1599 			      const unsigned char *addr, u16 vid,
1600 			      bool swdev_notify)
1601 {
1602 	struct net_bridge_fdb_entry *fdb;
1603 	int err = 0;
1604 
1605 	spin_lock_bh(&br->hash_lock);
1606 
1607 	fdb = br_fdb_find(br, addr, vid);
1608 	if (fdb && test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags))
1609 		fdb_delete(br, fdb, swdev_notify);
1610 	else
1611 		err = -ENOENT;
1612 
1613 	spin_unlock_bh(&br->hash_lock);
1614 
1615 	return err;
1616 }
1617 
1618 void br_fdb_offloaded_set(struct net_bridge *br, struct net_bridge_port *p,
1619 			  const unsigned char *addr, u16 vid, bool offloaded)
1620 {
1621 	struct net_bridge_fdb_entry *fdb;
1622 
1623 	spin_lock_bh(&br->hash_lock);
1624 
1625 	fdb = br_fdb_find(br, addr, vid);
1626 	if (fdb && offloaded != test_bit(BR_FDB_OFFLOADED, &fdb->flags))
1627 		change_bit(BR_FDB_OFFLOADED, &fdb->flags);
1628 
1629 	spin_unlock_bh(&br->hash_lock);
1630 }
1631 
1632 void br_fdb_clear_offload(const struct net_device *dev, u16 vid)
1633 {
1634 	struct net_bridge_fdb_entry *f;
1635 	struct net_bridge_port *p;
1636 
1637 	ASSERT_RTNL();
1638 
1639 	p = br_port_get_rtnl(dev);
1640 	if (!p)
1641 		return;
1642 
1643 	spin_lock_bh(&p->br->hash_lock);
1644 	hlist_for_each_entry(f, &p->br->fdb_list, fdb_node) {
1645 		if (f->dst == p && f->key.vlan_id == vid)
1646 			clear_bit(BR_FDB_OFFLOADED, &f->flags);
1647 	}
1648 	spin_unlock_bh(&p->br->hash_lock);
1649 }
1650 EXPORT_SYMBOL_GPL(br_fdb_clear_offload);
1651