xref: /linux/net/bridge/br_fdb.c (revision ce6b6d1513965f500a05f3facf223fa01fd74920)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *	Forwarding database
4  *	Linux ethernet bridge
5  *
6  *	Authors:
7  *	Lennert Buytenhek		<buytenh@gnu.org>
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/init.h>
12 #include <linux/rculist.h>
13 #include <linux/spinlock.h>
14 #include <linux/times.h>
15 #include <linux/netdevice.h>
16 #include <linux/etherdevice.h>
17 #include <linux/jhash.h>
18 #include <linux/random.h>
19 #include <linux/slab.h>
20 #include <linux/atomic.h>
21 #include <asm/unaligned.h>
22 #include <linux/if_vlan.h>
23 #include <net/switchdev.h>
24 #include <trace/events/bridge.h>
25 #include "br_private.h"
26 
27 static const struct rhashtable_params br_fdb_rht_params = {
28 	.head_offset = offsetof(struct net_bridge_fdb_entry, rhnode),
29 	.key_offset = offsetof(struct net_bridge_fdb_entry, key),
30 	.key_len = sizeof(struct net_bridge_fdb_key),
31 	.automatic_shrinking = true,
32 };
33 
34 static struct kmem_cache *br_fdb_cache __read_mostly;
35 
36 int __init br_fdb_init(void)
37 {
38 	br_fdb_cache = kmem_cache_create("bridge_fdb_cache",
39 					 sizeof(struct net_bridge_fdb_entry),
40 					 0,
41 					 SLAB_HWCACHE_ALIGN, NULL);
42 	if (!br_fdb_cache)
43 		return -ENOMEM;
44 
45 	return 0;
46 }
47 
48 void br_fdb_fini(void)
49 {
50 	kmem_cache_destroy(br_fdb_cache);
51 }
52 
53 int br_fdb_hash_init(struct net_bridge *br)
54 {
55 	return rhashtable_init(&br->fdb_hash_tbl, &br_fdb_rht_params);
56 }
57 
58 void br_fdb_hash_fini(struct net_bridge *br)
59 {
60 	rhashtable_destroy(&br->fdb_hash_tbl);
61 }
62 
63 /* if topology_changing then use forward_delay (default 15 sec)
64  * otherwise keep longer (default 5 minutes)
65  */
66 static inline unsigned long hold_time(const struct net_bridge *br)
67 {
68 	return br->topology_change ? br->forward_delay : br->ageing_time;
69 }
70 
71 static inline int has_expired(const struct net_bridge *br,
72 				  const struct net_bridge_fdb_entry *fdb)
73 {
74 	return !test_bit(BR_FDB_STATIC, &fdb->flags) &&
75 	       !test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags) &&
76 	       time_before_eq(fdb->updated + hold_time(br), jiffies);
77 }
78 
79 static void fdb_rcu_free(struct rcu_head *head)
80 {
81 	struct net_bridge_fdb_entry *ent
82 		= container_of(head, struct net_bridge_fdb_entry, rcu);
83 	kmem_cache_free(br_fdb_cache, ent);
84 }
85 
86 static int fdb_to_nud(const struct net_bridge *br,
87 		      const struct net_bridge_fdb_entry *fdb)
88 {
89 	if (test_bit(BR_FDB_LOCAL, &fdb->flags))
90 		return NUD_PERMANENT;
91 	else if (test_bit(BR_FDB_STATIC, &fdb->flags))
92 		return NUD_NOARP;
93 	else if (has_expired(br, fdb))
94 		return NUD_STALE;
95 	else
96 		return NUD_REACHABLE;
97 }
98 
99 static int fdb_fill_info(struct sk_buff *skb, const struct net_bridge *br,
100 			 const struct net_bridge_fdb_entry *fdb,
101 			 u32 portid, u32 seq, int type, unsigned int flags)
102 {
103 	const struct net_bridge_port *dst = READ_ONCE(fdb->dst);
104 	unsigned long now = jiffies;
105 	struct nda_cacheinfo ci;
106 	struct nlmsghdr *nlh;
107 	struct ndmsg *ndm;
108 	u32 ext_flags = 0;
109 
110 	nlh = nlmsg_put(skb, portid, seq, type, sizeof(*ndm), flags);
111 	if (nlh == NULL)
112 		return -EMSGSIZE;
113 
114 	ndm = nlmsg_data(nlh);
115 	ndm->ndm_family	 = AF_BRIDGE;
116 	ndm->ndm_pad1    = 0;
117 	ndm->ndm_pad2    = 0;
118 	ndm->ndm_flags	 = 0;
119 	ndm->ndm_type	 = 0;
120 	ndm->ndm_ifindex = dst ? dst->dev->ifindex : br->dev->ifindex;
121 	ndm->ndm_state   = fdb_to_nud(br, fdb);
122 
123 	if (test_bit(BR_FDB_OFFLOADED, &fdb->flags))
124 		ndm->ndm_flags |= NTF_OFFLOADED;
125 	if (test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags))
126 		ndm->ndm_flags |= NTF_EXT_LEARNED;
127 	if (test_bit(BR_FDB_STICKY, &fdb->flags))
128 		ndm->ndm_flags |= NTF_STICKY;
129 	if (test_bit(BR_FDB_LOCKED, &fdb->flags))
130 		ext_flags |= NTF_EXT_LOCKED;
131 
132 	if (nla_put(skb, NDA_LLADDR, ETH_ALEN, &fdb->key.addr))
133 		goto nla_put_failure;
134 	if (nla_put_u32(skb, NDA_MASTER, br->dev->ifindex))
135 		goto nla_put_failure;
136 	if (nla_put_u32(skb, NDA_FLAGS_EXT, ext_flags))
137 		goto nla_put_failure;
138 
139 	ci.ndm_used	 = jiffies_to_clock_t(now - fdb->used);
140 	ci.ndm_confirmed = 0;
141 	ci.ndm_updated	 = jiffies_to_clock_t(now - fdb->updated);
142 	ci.ndm_refcnt	 = 0;
143 	if (nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci))
144 		goto nla_put_failure;
145 
146 	if (fdb->key.vlan_id && nla_put(skb, NDA_VLAN, sizeof(u16),
147 					&fdb->key.vlan_id))
148 		goto nla_put_failure;
149 
150 	if (test_bit(BR_FDB_NOTIFY, &fdb->flags)) {
151 		struct nlattr *nest = nla_nest_start(skb, NDA_FDB_EXT_ATTRS);
152 		u8 notify_bits = FDB_NOTIFY_BIT;
153 
154 		if (!nest)
155 			goto nla_put_failure;
156 		if (test_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags))
157 			notify_bits |= FDB_NOTIFY_INACTIVE_BIT;
158 
159 		if (nla_put_u8(skb, NFEA_ACTIVITY_NOTIFY, notify_bits)) {
160 			nla_nest_cancel(skb, nest);
161 			goto nla_put_failure;
162 		}
163 
164 		nla_nest_end(skb, nest);
165 	}
166 
167 	nlmsg_end(skb, nlh);
168 	return 0;
169 
170 nla_put_failure:
171 	nlmsg_cancel(skb, nlh);
172 	return -EMSGSIZE;
173 }
174 
175 static inline size_t fdb_nlmsg_size(void)
176 {
177 	return NLMSG_ALIGN(sizeof(struct ndmsg))
178 		+ nla_total_size(ETH_ALEN) /* NDA_LLADDR */
179 		+ nla_total_size(sizeof(u32)) /* NDA_MASTER */
180 		+ nla_total_size(sizeof(u32)) /* NDA_FLAGS_EXT */
181 		+ nla_total_size(sizeof(u16)) /* NDA_VLAN */
182 		+ nla_total_size(sizeof(struct nda_cacheinfo))
183 		+ nla_total_size(0) /* NDA_FDB_EXT_ATTRS */
184 		+ nla_total_size(sizeof(u8)); /* NFEA_ACTIVITY_NOTIFY */
185 }
186 
187 static void fdb_notify(struct net_bridge *br,
188 		       const struct net_bridge_fdb_entry *fdb, int type,
189 		       bool swdev_notify)
190 {
191 	struct net *net = dev_net(br->dev);
192 	struct sk_buff *skb;
193 	int err = -ENOBUFS;
194 
195 	if (swdev_notify)
196 		br_switchdev_fdb_notify(br, fdb, type);
197 
198 	skb = nlmsg_new(fdb_nlmsg_size(), GFP_ATOMIC);
199 	if (skb == NULL)
200 		goto errout;
201 
202 	err = fdb_fill_info(skb, br, fdb, 0, 0, type, 0);
203 	if (err < 0) {
204 		/* -EMSGSIZE implies BUG in fdb_nlmsg_size() */
205 		WARN_ON(err == -EMSGSIZE);
206 		kfree_skb(skb);
207 		goto errout;
208 	}
209 	rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
210 	return;
211 errout:
212 	rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
213 }
214 
215 static struct net_bridge_fdb_entry *fdb_find_rcu(struct rhashtable *tbl,
216 						 const unsigned char *addr,
217 						 __u16 vid)
218 {
219 	struct net_bridge_fdb_key key;
220 
221 	WARN_ON_ONCE(!rcu_read_lock_held());
222 
223 	key.vlan_id = vid;
224 	memcpy(key.addr.addr, addr, sizeof(key.addr.addr));
225 
226 	return rhashtable_lookup(tbl, &key, br_fdb_rht_params);
227 }
228 
229 /* requires bridge hash_lock */
230 static struct net_bridge_fdb_entry *br_fdb_find(struct net_bridge *br,
231 						const unsigned char *addr,
232 						__u16 vid)
233 {
234 	struct net_bridge_fdb_entry *fdb;
235 
236 	lockdep_assert_held_once(&br->hash_lock);
237 
238 	rcu_read_lock();
239 	fdb = fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
240 	rcu_read_unlock();
241 
242 	return fdb;
243 }
244 
245 struct net_device *br_fdb_find_port(const struct net_device *br_dev,
246 				    const unsigned char *addr,
247 				    __u16 vid)
248 {
249 	struct net_bridge_fdb_entry *f;
250 	struct net_device *dev = NULL;
251 	struct net_bridge *br;
252 
253 	ASSERT_RTNL();
254 
255 	if (!netif_is_bridge_master(br_dev))
256 		return NULL;
257 
258 	br = netdev_priv(br_dev);
259 	rcu_read_lock();
260 	f = br_fdb_find_rcu(br, addr, vid);
261 	if (f && f->dst)
262 		dev = f->dst->dev;
263 	rcu_read_unlock();
264 
265 	return dev;
266 }
267 EXPORT_SYMBOL_GPL(br_fdb_find_port);
268 
269 struct net_bridge_fdb_entry *br_fdb_find_rcu(struct net_bridge *br,
270 					     const unsigned char *addr,
271 					     __u16 vid)
272 {
273 	return fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
274 }
275 
276 /* When a static FDB entry is added, the mac address from the entry is
277  * added to the bridge private HW address list and all required ports
278  * are then updated with the new information.
279  * Called under RTNL.
280  */
281 static void fdb_add_hw_addr(struct net_bridge *br, const unsigned char *addr)
282 {
283 	int err;
284 	struct net_bridge_port *p;
285 
286 	ASSERT_RTNL();
287 
288 	list_for_each_entry(p, &br->port_list, list) {
289 		if (!br_promisc_port(p)) {
290 			err = dev_uc_add(p->dev, addr);
291 			if (err)
292 				goto undo;
293 		}
294 	}
295 
296 	return;
297 undo:
298 	list_for_each_entry_continue_reverse(p, &br->port_list, list) {
299 		if (!br_promisc_port(p))
300 			dev_uc_del(p->dev, addr);
301 	}
302 }
303 
304 /* When a static FDB entry is deleted, the HW address from that entry is
305  * also removed from the bridge private HW address list and updates all
306  * the ports with needed information.
307  * Called under RTNL.
308  */
309 static void fdb_del_hw_addr(struct net_bridge *br, const unsigned char *addr)
310 {
311 	struct net_bridge_port *p;
312 
313 	ASSERT_RTNL();
314 
315 	list_for_each_entry(p, &br->port_list, list) {
316 		if (!br_promisc_port(p))
317 			dev_uc_del(p->dev, addr);
318 	}
319 }
320 
321 static void fdb_delete(struct net_bridge *br, struct net_bridge_fdb_entry *f,
322 		       bool swdev_notify)
323 {
324 	trace_fdb_delete(br, f);
325 
326 	if (test_bit(BR_FDB_STATIC, &f->flags))
327 		fdb_del_hw_addr(br, f->key.addr.addr);
328 
329 	hlist_del_init_rcu(&f->fdb_node);
330 	rhashtable_remove_fast(&br->fdb_hash_tbl, &f->rhnode,
331 			       br_fdb_rht_params);
332 	if (test_and_clear_bit(BR_FDB_DYNAMIC_LEARNED, &f->flags))
333 		atomic_dec(&br->fdb_n_learned);
334 	fdb_notify(br, f, RTM_DELNEIGH, swdev_notify);
335 	call_rcu(&f->rcu, fdb_rcu_free);
336 }
337 
338 /* Delete a local entry if no other port had the same address.
339  *
340  * This function should only be called on entries with BR_FDB_LOCAL set,
341  * so even with BR_FDB_ADDED_BY_USER cleared we never need to increase
342  * the accounting for dynamically learned entries again.
343  */
344 static void fdb_delete_local(struct net_bridge *br,
345 			     const struct net_bridge_port *p,
346 			     struct net_bridge_fdb_entry *f)
347 {
348 	const unsigned char *addr = f->key.addr.addr;
349 	struct net_bridge_vlan_group *vg;
350 	const struct net_bridge_vlan *v;
351 	struct net_bridge_port *op;
352 	u16 vid = f->key.vlan_id;
353 
354 	/* Maybe another port has same hw addr? */
355 	list_for_each_entry(op, &br->port_list, list) {
356 		vg = nbp_vlan_group(op);
357 		if (op != p && ether_addr_equal(op->dev->dev_addr, addr) &&
358 		    (!vid || br_vlan_find(vg, vid))) {
359 			f->dst = op;
360 			clear_bit(BR_FDB_ADDED_BY_USER, &f->flags);
361 			return;
362 		}
363 	}
364 
365 	vg = br_vlan_group(br);
366 	v = br_vlan_find(vg, vid);
367 	/* Maybe bridge device has same hw addr? */
368 	if (p && ether_addr_equal(br->dev->dev_addr, addr) &&
369 	    (!vid || (v && br_vlan_should_use(v)))) {
370 		f->dst = NULL;
371 		clear_bit(BR_FDB_ADDED_BY_USER, &f->flags);
372 		return;
373 	}
374 
375 	fdb_delete(br, f, true);
376 }
377 
378 void br_fdb_find_delete_local(struct net_bridge *br,
379 			      const struct net_bridge_port *p,
380 			      const unsigned char *addr, u16 vid)
381 {
382 	struct net_bridge_fdb_entry *f;
383 
384 	spin_lock_bh(&br->hash_lock);
385 	f = br_fdb_find(br, addr, vid);
386 	if (f && test_bit(BR_FDB_LOCAL, &f->flags) &&
387 	    !test_bit(BR_FDB_ADDED_BY_USER, &f->flags) && f->dst == p)
388 		fdb_delete_local(br, p, f);
389 	spin_unlock_bh(&br->hash_lock);
390 }
391 
392 static struct net_bridge_fdb_entry *fdb_create(struct net_bridge *br,
393 					       struct net_bridge_port *source,
394 					       const unsigned char *addr,
395 					       __u16 vid,
396 					       unsigned long flags)
397 {
398 	bool learned = !test_bit(BR_FDB_ADDED_BY_USER, &flags) &&
399 		       !test_bit(BR_FDB_LOCAL, &flags);
400 	u32 max_learned = READ_ONCE(br->fdb_max_learned);
401 	struct net_bridge_fdb_entry *fdb;
402 	int err;
403 
404 	if (likely(learned)) {
405 		int n_learned = atomic_read(&br->fdb_n_learned);
406 
407 		if (unlikely(max_learned && n_learned >= max_learned))
408 			return NULL;
409 		__set_bit(BR_FDB_DYNAMIC_LEARNED, &flags);
410 	}
411 
412 	fdb = kmem_cache_alloc(br_fdb_cache, GFP_ATOMIC);
413 	if (!fdb)
414 		return NULL;
415 
416 	memcpy(fdb->key.addr.addr, addr, ETH_ALEN);
417 	WRITE_ONCE(fdb->dst, source);
418 	fdb->key.vlan_id = vid;
419 	fdb->flags = flags;
420 	fdb->updated = fdb->used = jiffies;
421 	err = rhashtable_lookup_insert_fast(&br->fdb_hash_tbl, &fdb->rhnode,
422 					    br_fdb_rht_params);
423 	if (err) {
424 		kmem_cache_free(br_fdb_cache, fdb);
425 		return NULL;
426 	}
427 
428 	if (likely(learned))
429 		atomic_inc(&br->fdb_n_learned);
430 
431 	hlist_add_head_rcu(&fdb->fdb_node, &br->fdb_list);
432 
433 	return fdb;
434 }
435 
436 static int fdb_add_local(struct net_bridge *br, struct net_bridge_port *source,
437 			 const unsigned char *addr, u16 vid)
438 {
439 	struct net_bridge_fdb_entry *fdb;
440 
441 	if (!is_valid_ether_addr(addr))
442 		return -EINVAL;
443 
444 	fdb = br_fdb_find(br, addr, vid);
445 	if (fdb) {
446 		/* it is okay to have multiple ports with same
447 		 * address, just use the first one.
448 		 */
449 		if (test_bit(BR_FDB_LOCAL, &fdb->flags))
450 			return 0;
451 		br_warn(br, "adding interface %s with same address as a received packet (addr:%pM, vlan:%u)\n",
452 			source ? source->dev->name : br->dev->name, addr, vid);
453 		fdb_delete(br, fdb, true);
454 	}
455 
456 	fdb = fdb_create(br, source, addr, vid,
457 			 BIT(BR_FDB_LOCAL) | BIT(BR_FDB_STATIC));
458 	if (!fdb)
459 		return -ENOMEM;
460 
461 	fdb_add_hw_addr(br, addr);
462 	fdb_notify(br, fdb, RTM_NEWNEIGH, true);
463 	return 0;
464 }
465 
466 void br_fdb_changeaddr(struct net_bridge_port *p, const unsigned char *newaddr)
467 {
468 	struct net_bridge_vlan_group *vg;
469 	struct net_bridge_fdb_entry *f;
470 	struct net_bridge *br = p->br;
471 	struct net_bridge_vlan *v;
472 
473 	spin_lock_bh(&br->hash_lock);
474 	vg = nbp_vlan_group(p);
475 	hlist_for_each_entry(f, &br->fdb_list, fdb_node) {
476 		if (f->dst == p && test_bit(BR_FDB_LOCAL, &f->flags) &&
477 		    !test_bit(BR_FDB_ADDED_BY_USER, &f->flags)) {
478 			/* delete old one */
479 			fdb_delete_local(br, p, f);
480 
481 			/* if this port has no vlan information
482 			 * configured, we can safely be done at
483 			 * this point.
484 			 */
485 			if (!vg || !vg->num_vlans)
486 				goto insert;
487 		}
488 	}
489 
490 insert:
491 	/* insert new address,  may fail if invalid address or dup. */
492 	fdb_add_local(br, p, newaddr, 0);
493 
494 	if (!vg || !vg->num_vlans)
495 		goto done;
496 
497 	/* Now add entries for every VLAN configured on the port.
498 	 * This function runs under RTNL so the bitmap will not change
499 	 * from under us.
500 	 */
501 	list_for_each_entry(v, &vg->vlan_list, vlist)
502 		fdb_add_local(br, p, newaddr, v->vid);
503 
504 done:
505 	spin_unlock_bh(&br->hash_lock);
506 }
507 
508 void br_fdb_change_mac_address(struct net_bridge *br, const u8 *newaddr)
509 {
510 	struct net_bridge_vlan_group *vg;
511 	struct net_bridge_fdb_entry *f;
512 	struct net_bridge_vlan *v;
513 
514 	spin_lock_bh(&br->hash_lock);
515 
516 	/* If old entry was unassociated with any port, then delete it. */
517 	f = br_fdb_find(br, br->dev->dev_addr, 0);
518 	if (f && test_bit(BR_FDB_LOCAL, &f->flags) &&
519 	    !f->dst && !test_bit(BR_FDB_ADDED_BY_USER, &f->flags))
520 		fdb_delete_local(br, NULL, f);
521 
522 	fdb_add_local(br, NULL, newaddr, 0);
523 	vg = br_vlan_group(br);
524 	if (!vg || !vg->num_vlans)
525 		goto out;
526 	/* Now remove and add entries for every VLAN configured on the
527 	 * bridge.  This function runs under RTNL so the bitmap will not
528 	 * change from under us.
529 	 */
530 	list_for_each_entry(v, &vg->vlan_list, vlist) {
531 		if (!br_vlan_should_use(v))
532 			continue;
533 		f = br_fdb_find(br, br->dev->dev_addr, v->vid);
534 		if (f && test_bit(BR_FDB_LOCAL, &f->flags) &&
535 		    !f->dst && !test_bit(BR_FDB_ADDED_BY_USER, &f->flags))
536 			fdb_delete_local(br, NULL, f);
537 		fdb_add_local(br, NULL, newaddr, v->vid);
538 	}
539 out:
540 	spin_unlock_bh(&br->hash_lock);
541 }
542 
543 void br_fdb_cleanup(struct work_struct *work)
544 {
545 	struct net_bridge *br = container_of(work, struct net_bridge,
546 					     gc_work.work);
547 	struct net_bridge_fdb_entry *f = NULL;
548 	unsigned long delay = hold_time(br);
549 	unsigned long work_delay = delay;
550 	unsigned long now = jiffies;
551 
552 	/* this part is tricky, in order to avoid blocking learning and
553 	 * consequently forwarding, we rely on rcu to delete objects with
554 	 * delayed freeing allowing us to continue traversing
555 	 */
556 	rcu_read_lock();
557 	hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
558 		unsigned long this_timer = f->updated + delay;
559 
560 		if (test_bit(BR_FDB_STATIC, &f->flags) ||
561 		    test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &f->flags)) {
562 			if (test_bit(BR_FDB_NOTIFY, &f->flags)) {
563 				if (time_after(this_timer, now))
564 					work_delay = min(work_delay,
565 							 this_timer - now);
566 				else if (!test_and_set_bit(BR_FDB_NOTIFY_INACTIVE,
567 							   &f->flags))
568 					fdb_notify(br, f, RTM_NEWNEIGH, false);
569 			}
570 			continue;
571 		}
572 
573 		if (time_after(this_timer, now)) {
574 			work_delay = min(work_delay, this_timer - now);
575 		} else {
576 			spin_lock_bh(&br->hash_lock);
577 			if (!hlist_unhashed(&f->fdb_node))
578 				fdb_delete(br, f, true);
579 			spin_unlock_bh(&br->hash_lock);
580 		}
581 	}
582 	rcu_read_unlock();
583 
584 	/* Cleanup minimum 10 milliseconds apart */
585 	work_delay = max_t(unsigned long, work_delay, msecs_to_jiffies(10));
586 	mod_delayed_work(system_long_wq, &br->gc_work, work_delay);
587 }
588 
589 static bool __fdb_flush_matches(const struct net_bridge *br,
590 				const struct net_bridge_fdb_entry *f,
591 				const struct net_bridge_fdb_flush_desc *desc)
592 {
593 	const struct net_bridge_port *dst = READ_ONCE(f->dst);
594 	int port_ifidx = dst ? dst->dev->ifindex : br->dev->ifindex;
595 
596 	if (desc->vlan_id && desc->vlan_id != f->key.vlan_id)
597 		return false;
598 	if (desc->port_ifindex && desc->port_ifindex != port_ifidx)
599 		return false;
600 	if (desc->flags_mask && (f->flags & desc->flags_mask) != desc->flags)
601 		return false;
602 
603 	return true;
604 }
605 
606 /* Flush forwarding database entries matching the description */
607 void br_fdb_flush(struct net_bridge *br,
608 		  const struct net_bridge_fdb_flush_desc *desc)
609 {
610 	struct net_bridge_fdb_entry *f;
611 
612 	rcu_read_lock();
613 	hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
614 		if (!__fdb_flush_matches(br, f, desc))
615 			continue;
616 
617 		spin_lock_bh(&br->hash_lock);
618 		if (!hlist_unhashed(&f->fdb_node))
619 			fdb_delete(br, f, true);
620 		spin_unlock_bh(&br->hash_lock);
621 	}
622 	rcu_read_unlock();
623 }
624 
625 static unsigned long __ndm_state_to_fdb_flags(u16 ndm_state)
626 {
627 	unsigned long flags = 0;
628 
629 	if (ndm_state & NUD_PERMANENT)
630 		__set_bit(BR_FDB_LOCAL, &flags);
631 	if (ndm_state & NUD_NOARP)
632 		__set_bit(BR_FDB_STATIC, &flags);
633 
634 	return flags;
635 }
636 
637 static unsigned long __ndm_flags_to_fdb_flags(u8 ndm_flags)
638 {
639 	unsigned long flags = 0;
640 
641 	if (ndm_flags & NTF_USE)
642 		__set_bit(BR_FDB_ADDED_BY_USER, &flags);
643 	if (ndm_flags & NTF_EXT_LEARNED)
644 		__set_bit(BR_FDB_ADDED_BY_EXT_LEARN, &flags);
645 	if (ndm_flags & NTF_OFFLOADED)
646 		__set_bit(BR_FDB_OFFLOADED, &flags);
647 	if (ndm_flags & NTF_STICKY)
648 		__set_bit(BR_FDB_STICKY, &flags);
649 
650 	return flags;
651 }
652 
653 static int __fdb_flush_validate_ifindex(const struct net_bridge *br,
654 					int ifindex,
655 					struct netlink_ext_ack *extack)
656 {
657 	const struct net_device *dev;
658 
659 	dev = __dev_get_by_index(dev_net(br->dev), ifindex);
660 	if (!dev) {
661 		NL_SET_ERR_MSG_MOD(extack, "Unknown flush device ifindex");
662 		return -ENODEV;
663 	}
664 	if (!netif_is_bridge_master(dev) && !netif_is_bridge_port(dev)) {
665 		NL_SET_ERR_MSG_MOD(extack, "Flush device is not a bridge or bridge port");
666 		return -EINVAL;
667 	}
668 	if (netif_is_bridge_master(dev) && dev != br->dev) {
669 		NL_SET_ERR_MSG_MOD(extack,
670 				   "Flush bridge device does not match target bridge device");
671 		return -EINVAL;
672 	}
673 	if (netif_is_bridge_port(dev)) {
674 		struct net_bridge_port *p = br_port_get_rtnl(dev);
675 
676 		if (p->br != br) {
677 			NL_SET_ERR_MSG_MOD(extack, "Port belongs to a different bridge device");
678 			return -EINVAL;
679 		}
680 	}
681 
682 	return 0;
683 }
684 
685 static const struct nla_policy br_fdb_del_bulk_policy[NDA_MAX + 1] = {
686 	[NDA_VLAN]	= NLA_POLICY_RANGE(NLA_U16, 1, VLAN_N_VID - 2),
687 	[NDA_IFINDEX]	= NLA_POLICY_MIN(NLA_S32, 1),
688 	[NDA_NDM_STATE_MASK]	= { .type = NLA_U16 },
689 	[NDA_NDM_FLAGS_MASK]	= { .type = NLA_U8 },
690 };
691 
692 int br_fdb_delete_bulk(struct nlmsghdr *nlh, struct net_device *dev,
693 		       struct netlink_ext_ack *extack)
694 {
695 	struct net_bridge_fdb_flush_desc desc = {};
696 	struct ndmsg *ndm = nlmsg_data(nlh);
697 	struct net_bridge_port *p = NULL;
698 	struct nlattr *tb[NDA_MAX + 1];
699 	struct net_bridge *br;
700 	u8 ndm_flags;
701 	int err;
702 
703 	ndm_flags = ndm->ndm_flags & ~FDB_FLUSH_IGNORED_NDM_FLAGS;
704 
705 	err = nlmsg_parse(nlh, sizeof(*ndm), tb, NDA_MAX,
706 			  br_fdb_del_bulk_policy, extack);
707 	if (err)
708 		return err;
709 
710 	if (netif_is_bridge_master(dev)) {
711 		br = netdev_priv(dev);
712 	} else {
713 		p = br_port_get_rtnl(dev);
714 		if (!p) {
715 			NL_SET_ERR_MSG_MOD(extack, "Device is not a bridge port");
716 			return -EINVAL;
717 		}
718 		br = p->br;
719 	}
720 
721 	if (tb[NDA_VLAN])
722 		desc.vlan_id = nla_get_u16(tb[NDA_VLAN]);
723 
724 	if (ndm_flags & ~FDB_FLUSH_ALLOWED_NDM_FLAGS) {
725 		NL_SET_ERR_MSG(extack, "Unsupported fdb flush ndm flag bits set");
726 		return -EINVAL;
727 	}
728 	if (ndm->ndm_state & ~FDB_FLUSH_ALLOWED_NDM_STATES) {
729 		NL_SET_ERR_MSG(extack, "Unsupported fdb flush ndm state bits set");
730 		return -EINVAL;
731 	}
732 
733 	desc.flags |= __ndm_state_to_fdb_flags(ndm->ndm_state);
734 	desc.flags |= __ndm_flags_to_fdb_flags(ndm_flags);
735 	if (tb[NDA_NDM_STATE_MASK]) {
736 		u16 ndm_state_mask = nla_get_u16(tb[NDA_NDM_STATE_MASK]);
737 
738 		desc.flags_mask |= __ndm_state_to_fdb_flags(ndm_state_mask);
739 	}
740 	if (tb[NDA_NDM_FLAGS_MASK]) {
741 		u8 ndm_flags_mask = nla_get_u8(tb[NDA_NDM_FLAGS_MASK]);
742 
743 		desc.flags_mask |= __ndm_flags_to_fdb_flags(ndm_flags_mask);
744 	}
745 	if (tb[NDA_IFINDEX]) {
746 		int ifidx = nla_get_s32(tb[NDA_IFINDEX]);
747 
748 		err = __fdb_flush_validate_ifindex(br, ifidx, extack);
749 		if (err)
750 			return err;
751 		desc.port_ifindex = ifidx;
752 	} else if (p) {
753 		/* flush was invoked with port device and NTF_MASTER */
754 		desc.port_ifindex = p->dev->ifindex;
755 	}
756 
757 	br_debug(br, "flushing port ifindex: %d vlan id: %u flags: 0x%lx flags mask: 0x%lx\n",
758 		 desc.port_ifindex, desc.vlan_id, desc.flags, desc.flags_mask);
759 
760 	br_fdb_flush(br, &desc);
761 
762 	return 0;
763 }
764 
765 /* Flush all entries referring to a specific port.
766  * if do_all is set also flush static entries
767  * if vid is set delete all entries that match the vlan_id
768  */
769 void br_fdb_delete_by_port(struct net_bridge *br,
770 			   const struct net_bridge_port *p,
771 			   u16 vid,
772 			   int do_all)
773 {
774 	struct net_bridge_fdb_entry *f;
775 	struct hlist_node *tmp;
776 
777 	spin_lock_bh(&br->hash_lock);
778 	hlist_for_each_entry_safe(f, tmp, &br->fdb_list, fdb_node) {
779 		if (f->dst != p)
780 			continue;
781 
782 		if (!do_all)
783 			if (test_bit(BR_FDB_STATIC, &f->flags) ||
784 			    (test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &f->flags) &&
785 			     !test_bit(BR_FDB_OFFLOADED, &f->flags)) ||
786 			    (vid && f->key.vlan_id != vid))
787 				continue;
788 
789 		if (test_bit(BR_FDB_LOCAL, &f->flags))
790 			fdb_delete_local(br, p, f);
791 		else
792 			fdb_delete(br, f, true);
793 	}
794 	spin_unlock_bh(&br->hash_lock);
795 }
796 
797 #if IS_ENABLED(CONFIG_ATM_LANE)
798 /* Interface used by ATM LANE hook to test
799  * if an addr is on some other bridge port */
800 int br_fdb_test_addr(struct net_device *dev, unsigned char *addr)
801 {
802 	struct net_bridge_fdb_entry *fdb;
803 	struct net_bridge_port *port;
804 	int ret;
805 
806 	rcu_read_lock();
807 	port = br_port_get_rcu(dev);
808 	if (!port)
809 		ret = 0;
810 	else {
811 		const struct net_bridge_port *dst = NULL;
812 
813 		fdb = br_fdb_find_rcu(port->br, addr, 0);
814 		if (fdb)
815 			dst = READ_ONCE(fdb->dst);
816 
817 		ret = dst && dst->dev != dev &&
818 		      dst->state == BR_STATE_FORWARDING;
819 	}
820 	rcu_read_unlock();
821 
822 	return ret;
823 }
824 #endif /* CONFIG_ATM_LANE */
825 
826 /*
827  * Fill buffer with forwarding table records in
828  * the API format.
829  */
830 int br_fdb_fillbuf(struct net_bridge *br, void *buf,
831 		   unsigned long maxnum, unsigned long skip)
832 {
833 	struct net_bridge_fdb_entry *f;
834 	struct __fdb_entry *fe = buf;
835 	int num = 0;
836 
837 	memset(buf, 0, maxnum*sizeof(struct __fdb_entry));
838 
839 	rcu_read_lock();
840 	hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
841 		if (num >= maxnum)
842 			break;
843 
844 		if (has_expired(br, f))
845 			continue;
846 
847 		/* ignore pseudo entry for local MAC address */
848 		if (!f->dst)
849 			continue;
850 
851 		if (skip) {
852 			--skip;
853 			continue;
854 		}
855 
856 		/* convert from internal format to API */
857 		memcpy(fe->mac_addr, f->key.addr.addr, ETH_ALEN);
858 
859 		/* due to ABI compat need to split into hi/lo */
860 		fe->port_no = f->dst->port_no;
861 		fe->port_hi = f->dst->port_no >> 8;
862 
863 		fe->is_local = test_bit(BR_FDB_LOCAL, &f->flags);
864 		if (!test_bit(BR_FDB_STATIC, &f->flags))
865 			fe->ageing_timer_value = jiffies_delta_to_clock_t(jiffies - f->updated);
866 		++fe;
867 		++num;
868 	}
869 	rcu_read_unlock();
870 
871 	return num;
872 }
873 
874 /* Add entry for local address of interface */
875 int br_fdb_add_local(struct net_bridge *br, struct net_bridge_port *source,
876 		     const unsigned char *addr, u16 vid)
877 {
878 	int ret;
879 
880 	spin_lock_bh(&br->hash_lock);
881 	ret = fdb_add_local(br, source, addr, vid);
882 	spin_unlock_bh(&br->hash_lock);
883 	return ret;
884 }
885 
886 /* returns true if the fdb was modified */
887 static bool __fdb_mark_active(struct net_bridge_fdb_entry *fdb)
888 {
889 	return !!(test_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags) &&
890 		  test_and_clear_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags));
891 }
892 
893 void br_fdb_update(struct net_bridge *br, struct net_bridge_port *source,
894 		   const unsigned char *addr, u16 vid, unsigned long flags)
895 {
896 	struct net_bridge_fdb_entry *fdb;
897 
898 	/* some users want to always flood. */
899 	if (hold_time(br) == 0)
900 		return;
901 
902 	fdb = fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
903 	if (likely(fdb)) {
904 		/* attempt to update an entry for a local interface */
905 		if (unlikely(test_bit(BR_FDB_LOCAL, &fdb->flags))) {
906 			if (net_ratelimit())
907 				br_warn(br, "received packet on %s with own address as source address (addr:%pM, vlan:%u)\n",
908 					source->dev->name, addr, vid);
909 		} else {
910 			unsigned long now = jiffies;
911 			bool fdb_modified = false;
912 
913 			if (now != fdb->updated) {
914 				fdb->updated = now;
915 				fdb_modified = __fdb_mark_active(fdb);
916 			}
917 
918 			/* fastpath: update of existing entry */
919 			if (unlikely(source != READ_ONCE(fdb->dst) &&
920 				     !test_bit(BR_FDB_STICKY, &fdb->flags))) {
921 				br_switchdev_fdb_notify(br, fdb, RTM_DELNEIGH);
922 				WRITE_ONCE(fdb->dst, source);
923 				fdb_modified = true;
924 				/* Take over HW learned entry */
925 				if (unlikely(test_bit(BR_FDB_ADDED_BY_EXT_LEARN,
926 						      &fdb->flags)))
927 					clear_bit(BR_FDB_ADDED_BY_EXT_LEARN,
928 						  &fdb->flags);
929 				/* Clear locked flag when roaming to an
930 				 * unlocked port.
931 				 */
932 				if (unlikely(test_bit(BR_FDB_LOCKED, &fdb->flags)))
933 					clear_bit(BR_FDB_LOCKED, &fdb->flags);
934 			}
935 
936 			if (unlikely(test_bit(BR_FDB_ADDED_BY_USER, &flags))) {
937 				set_bit(BR_FDB_ADDED_BY_USER, &fdb->flags);
938 				if (test_and_clear_bit(BR_FDB_DYNAMIC_LEARNED,
939 						       &fdb->flags))
940 					atomic_dec(&br->fdb_n_learned);
941 			}
942 			if (unlikely(fdb_modified)) {
943 				trace_br_fdb_update(br, source, addr, vid, flags);
944 				fdb_notify(br, fdb, RTM_NEWNEIGH, true);
945 			}
946 		}
947 	} else {
948 		spin_lock(&br->hash_lock);
949 		fdb = fdb_create(br, source, addr, vid, flags);
950 		if (fdb) {
951 			trace_br_fdb_update(br, source, addr, vid, flags);
952 			fdb_notify(br, fdb, RTM_NEWNEIGH, true);
953 		}
954 		/* else  we lose race and someone else inserts
955 		 * it first, don't bother updating
956 		 */
957 		spin_unlock(&br->hash_lock);
958 	}
959 }
960 
961 /* Dump information about entries, in response to GETNEIGH */
962 int br_fdb_dump(struct sk_buff *skb,
963 		struct netlink_callback *cb,
964 		struct net_device *dev,
965 		struct net_device *filter_dev,
966 		int *idx)
967 {
968 	struct net_bridge *br = netdev_priv(dev);
969 	struct net_bridge_fdb_entry *f;
970 	int err = 0;
971 
972 	if (!netif_is_bridge_master(dev))
973 		return err;
974 
975 	if (!filter_dev) {
976 		err = ndo_dflt_fdb_dump(skb, cb, dev, NULL, idx);
977 		if (err < 0)
978 			return err;
979 	}
980 
981 	rcu_read_lock();
982 	hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
983 		if (*idx < cb->args[2])
984 			goto skip;
985 		if (filter_dev && (!f->dst || f->dst->dev != filter_dev)) {
986 			if (filter_dev != dev)
987 				goto skip;
988 			/* !f->dst is a special case for bridge
989 			 * It means the MAC belongs to the bridge
990 			 * Therefore need a little more filtering
991 			 * we only want to dump the !f->dst case
992 			 */
993 			if (f->dst)
994 				goto skip;
995 		}
996 		if (!filter_dev && f->dst)
997 			goto skip;
998 
999 		err = fdb_fill_info(skb, br, f,
1000 				    NETLINK_CB(cb->skb).portid,
1001 				    cb->nlh->nlmsg_seq,
1002 				    RTM_NEWNEIGH,
1003 				    NLM_F_MULTI);
1004 		if (err < 0)
1005 			break;
1006 skip:
1007 		*idx += 1;
1008 	}
1009 	rcu_read_unlock();
1010 
1011 	return err;
1012 }
1013 
1014 int br_fdb_get(struct sk_buff *skb,
1015 	       struct nlattr *tb[],
1016 	       struct net_device *dev,
1017 	       const unsigned char *addr,
1018 	       u16 vid, u32 portid, u32 seq,
1019 	       struct netlink_ext_ack *extack)
1020 {
1021 	struct net_bridge *br = netdev_priv(dev);
1022 	struct net_bridge_fdb_entry *f;
1023 	int err = 0;
1024 
1025 	rcu_read_lock();
1026 	f = br_fdb_find_rcu(br, addr, vid);
1027 	if (!f) {
1028 		NL_SET_ERR_MSG(extack, "Fdb entry not found");
1029 		err = -ENOENT;
1030 		goto errout;
1031 	}
1032 
1033 	err = fdb_fill_info(skb, br, f, portid, seq,
1034 			    RTM_NEWNEIGH, 0);
1035 errout:
1036 	rcu_read_unlock();
1037 	return err;
1038 }
1039 
1040 /* returns true if the fdb is modified */
1041 static bool fdb_handle_notify(struct net_bridge_fdb_entry *fdb, u8 notify)
1042 {
1043 	bool modified = false;
1044 
1045 	/* allow to mark an entry as inactive, usually done on creation */
1046 	if ((notify & FDB_NOTIFY_INACTIVE_BIT) &&
1047 	    !test_and_set_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags))
1048 		modified = true;
1049 
1050 	if ((notify & FDB_NOTIFY_BIT) &&
1051 	    !test_and_set_bit(BR_FDB_NOTIFY, &fdb->flags)) {
1052 		/* enabled activity tracking */
1053 		modified = true;
1054 	} else if (!(notify & FDB_NOTIFY_BIT) &&
1055 		   test_and_clear_bit(BR_FDB_NOTIFY, &fdb->flags)) {
1056 		/* disabled activity tracking, clear notify state */
1057 		clear_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags);
1058 		modified = true;
1059 	}
1060 
1061 	return modified;
1062 }
1063 
1064 /* Update (create or replace) forwarding database entry */
1065 static int fdb_add_entry(struct net_bridge *br, struct net_bridge_port *source,
1066 			 const u8 *addr, struct ndmsg *ndm, u16 flags, u16 vid,
1067 			 struct nlattr *nfea_tb[])
1068 {
1069 	bool is_sticky = !!(ndm->ndm_flags & NTF_STICKY);
1070 	bool refresh = !nfea_tb[NFEA_DONT_REFRESH];
1071 	struct net_bridge_fdb_entry *fdb;
1072 	u16 state = ndm->ndm_state;
1073 	bool modified = false;
1074 	u8 notify = 0;
1075 
1076 	/* If the port cannot learn allow only local and static entries */
1077 	if (source && !(state & NUD_PERMANENT) && !(state & NUD_NOARP) &&
1078 	    !(source->state == BR_STATE_LEARNING ||
1079 	      source->state == BR_STATE_FORWARDING))
1080 		return -EPERM;
1081 
1082 	if (!source && !(state & NUD_PERMANENT)) {
1083 		pr_info("bridge: RTM_NEWNEIGH %s without NUD_PERMANENT\n",
1084 			br->dev->name);
1085 		return -EINVAL;
1086 	}
1087 
1088 	if (is_sticky && (state & NUD_PERMANENT))
1089 		return -EINVAL;
1090 
1091 	if (nfea_tb[NFEA_ACTIVITY_NOTIFY]) {
1092 		notify = nla_get_u8(nfea_tb[NFEA_ACTIVITY_NOTIFY]);
1093 		if ((notify & ~BR_FDB_NOTIFY_SETTABLE_BITS) ||
1094 		    (notify & BR_FDB_NOTIFY_SETTABLE_BITS) == FDB_NOTIFY_INACTIVE_BIT)
1095 			return -EINVAL;
1096 	}
1097 
1098 	fdb = br_fdb_find(br, addr, vid);
1099 	if (fdb == NULL) {
1100 		if (!(flags & NLM_F_CREATE))
1101 			return -ENOENT;
1102 
1103 		fdb = fdb_create(br, source, addr, vid,
1104 				 BIT(BR_FDB_ADDED_BY_USER));
1105 		if (!fdb)
1106 			return -ENOMEM;
1107 
1108 		modified = true;
1109 	} else {
1110 		if (flags & NLM_F_EXCL)
1111 			return -EEXIST;
1112 
1113 		if (READ_ONCE(fdb->dst) != source) {
1114 			WRITE_ONCE(fdb->dst, source);
1115 			modified = true;
1116 		}
1117 
1118 		set_bit(BR_FDB_ADDED_BY_USER, &fdb->flags);
1119 		if (test_and_clear_bit(BR_FDB_DYNAMIC_LEARNED, &fdb->flags))
1120 			atomic_dec(&br->fdb_n_learned);
1121 	}
1122 
1123 	if (fdb_to_nud(br, fdb) != state) {
1124 		if (state & NUD_PERMANENT) {
1125 			set_bit(BR_FDB_LOCAL, &fdb->flags);
1126 			if (!test_and_set_bit(BR_FDB_STATIC, &fdb->flags))
1127 				fdb_add_hw_addr(br, addr);
1128 		} else if (state & NUD_NOARP) {
1129 			clear_bit(BR_FDB_LOCAL, &fdb->flags);
1130 			if (!test_and_set_bit(BR_FDB_STATIC, &fdb->flags))
1131 				fdb_add_hw_addr(br, addr);
1132 		} else {
1133 			clear_bit(BR_FDB_LOCAL, &fdb->flags);
1134 			if (test_and_clear_bit(BR_FDB_STATIC, &fdb->flags))
1135 				fdb_del_hw_addr(br, addr);
1136 		}
1137 
1138 		modified = true;
1139 	}
1140 
1141 	if (is_sticky != test_bit(BR_FDB_STICKY, &fdb->flags)) {
1142 		change_bit(BR_FDB_STICKY, &fdb->flags);
1143 		modified = true;
1144 	}
1145 
1146 	if (test_and_clear_bit(BR_FDB_LOCKED, &fdb->flags))
1147 		modified = true;
1148 
1149 	if (fdb_handle_notify(fdb, notify))
1150 		modified = true;
1151 
1152 	fdb->used = jiffies;
1153 	if (modified) {
1154 		if (refresh)
1155 			fdb->updated = jiffies;
1156 		fdb_notify(br, fdb, RTM_NEWNEIGH, true);
1157 	}
1158 
1159 	return 0;
1160 }
1161 
1162 static int __br_fdb_add(struct ndmsg *ndm, struct net_bridge *br,
1163 			struct net_bridge_port *p, const unsigned char *addr,
1164 			u16 nlh_flags, u16 vid, struct nlattr *nfea_tb[],
1165 			struct netlink_ext_ack *extack)
1166 {
1167 	int err = 0;
1168 
1169 	if (ndm->ndm_flags & NTF_USE) {
1170 		if (!p) {
1171 			pr_info("bridge: RTM_NEWNEIGH %s with NTF_USE is not supported\n",
1172 				br->dev->name);
1173 			return -EINVAL;
1174 		}
1175 		if (!nbp_state_should_learn(p))
1176 			return 0;
1177 
1178 		local_bh_disable();
1179 		rcu_read_lock();
1180 		br_fdb_update(br, p, addr, vid, BIT(BR_FDB_ADDED_BY_USER));
1181 		rcu_read_unlock();
1182 		local_bh_enable();
1183 	} else if (ndm->ndm_flags & NTF_EXT_LEARNED) {
1184 		if (!p && !(ndm->ndm_state & NUD_PERMANENT)) {
1185 			NL_SET_ERR_MSG_MOD(extack,
1186 					   "FDB entry towards bridge must be permanent");
1187 			return -EINVAL;
1188 		}
1189 		err = br_fdb_external_learn_add(br, p, addr, vid, false, true);
1190 	} else {
1191 		spin_lock_bh(&br->hash_lock);
1192 		err = fdb_add_entry(br, p, addr, ndm, nlh_flags, vid, nfea_tb);
1193 		spin_unlock_bh(&br->hash_lock);
1194 	}
1195 
1196 	return err;
1197 }
1198 
1199 static const struct nla_policy br_nda_fdb_pol[NFEA_MAX + 1] = {
1200 	[NFEA_ACTIVITY_NOTIFY]	= { .type = NLA_U8 },
1201 	[NFEA_DONT_REFRESH]	= { .type = NLA_FLAG },
1202 };
1203 
1204 /* Add new permanent fdb entry with RTM_NEWNEIGH */
1205 int br_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
1206 	       struct net_device *dev,
1207 	       const unsigned char *addr, u16 vid, u16 nlh_flags,
1208 	       struct netlink_ext_ack *extack)
1209 {
1210 	struct nlattr *nfea_tb[NFEA_MAX + 1], *attr;
1211 	struct net_bridge_vlan_group *vg;
1212 	struct net_bridge_port *p = NULL;
1213 	struct net_bridge_vlan *v;
1214 	struct net_bridge *br = NULL;
1215 	u32 ext_flags = 0;
1216 	int err = 0;
1217 
1218 	trace_br_fdb_add(ndm, dev, addr, vid, nlh_flags);
1219 
1220 	if (!(ndm->ndm_state & (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE))) {
1221 		pr_info("bridge: RTM_NEWNEIGH with invalid state %#x\n", ndm->ndm_state);
1222 		return -EINVAL;
1223 	}
1224 
1225 	if (is_zero_ether_addr(addr)) {
1226 		pr_info("bridge: RTM_NEWNEIGH with invalid ether address\n");
1227 		return -EINVAL;
1228 	}
1229 
1230 	if (netif_is_bridge_master(dev)) {
1231 		br = netdev_priv(dev);
1232 		vg = br_vlan_group(br);
1233 	} else {
1234 		p = br_port_get_rtnl(dev);
1235 		if (!p) {
1236 			pr_info("bridge: RTM_NEWNEIGH %s not a bridge port\n",
1237 				dev->name);
1238 			return -EINVAL;
1239 		}
1240 		br = p->br;
1241 		vg = nbp_vlan_group(p);
1242 	}
1243 
1244 	if (tb[NDA_FLAGS_EXT])
1245 		ext_flags = nla_get_u32(tb[NDA_FLAGS_EXT]);
1246 
1247 	if (ext_flags & NTF_EXT_LOCKED) {
1248 		NL_SET_ERR_MSG_MOD(extack, "Cannot add FDB entry with \"locked\" flag set");
1249 		return -EINVAL;
1250 	}
1251 
1252 	if (tb[NDA_FDB_EXT_ATTRS]) {
1253 		attr = tb[NDA_FDB_EXT_ATTRS];
1254 		err = nla_parse_nested(nfea_tb, NFEA_MAX, attr,
1255 				       br_nda_fdb_pol, extack);
1256 		if (err)
1257 			return err;
1258 	} else {
1259 		memset(nfea_tb, 0, sizeof(struct nlattr *) * (NFEA_MAX + 1));
1260 	}
1261 
1262 	if (vid) {
1263 		v = br_vlan_find(vg, vid);
1264 		if (!v || !br_vlan_should_use(v)) {
1265 			pr_info("bridge: RTM_NEWNEIGH with unconfigured vlan %d on %s\n", vid, dev->name);
1266 			return -EINVAL;
1267 		}
1268 
1269 		/* VID was specified, so use it. */
1270 		err = __br_fdb_add(ndm, br, p, addr, nlh_flags, vid, nfea_tb,
1271 				   extack);
1272 	} else {
1273 		err = __br_fdb_add(ndm, br, p, addr, nlh_flags, 0, nfea_tb,
1274 				   extack);
1275 		if (err || !vg || !vg->num_vlans)
1276 			goto out;
1277 
1278 		/* We have vlans configured on this port and user didn't
1279 		 * specify a VLAN.  To be nice, add/update entry for every
1280 		 * vlan on this port.
1281 		 */
1282 		list_for_each_entry(v, &vg->vlan_list, vlist) {
1283 			if (!br_vlan_should_use(v))
1284 				continue;
1285 			err = __br_fdb_add(ndm, br, p, addr, nlh_flags, v->vid,
1286 					   nfea_tb, extack);
1287 			if (err)
1288 				goto out;
1289 		}
1290 	}
1291 
1292 out:
1293 	return err;
1294 }
1295 
1296 static int fdb_delete_by_addr_and_port(struct net_bridge *br,
1297 				       const struct net_bridge_port *p,
1298 				       const u8 *addr, u16 vlan)
1299 {
1300 	struct net_bridge_fdb_entry *fdb;
1301 
1302 	fdb = br_fdb_find(br, addr, vlan);
1303 	if (!fdb || READ_ONCE(fdb->dst) != p)
1304 		return -ENOENT;
1305 
1306 	fdb_delete(br, fdb, true);
1307 
1308 	return 0;
1309 }
1310 
1311 static int __br_fdb_delete(struct net_bridge *br,
1312 			   const struct net_bridge_port *p,
1313 			   const unsigned char *addr, u16 vid)
1314 {
1315 	int err;
1316 
1317 	spin_lock_bh(&br->hash_lock);
1318 	err = fdb_delete_by_addr_and_port(br, p, addr, vid);
1319 	spin_unlock_bh(&br->hash_lock);
1320 
1321 	return err;
1322 }
1323 
1324 /* Remove neighbor entry with RTM_DELNEIGH */
1325 int br_fdb_delete(struct ndmsg *ndm, struct nlattr *tb[],
1326 		  struct net_device *dev,
1327 		  const unsigned char *addr, u16 vid,
1328 		  struct netlink_ext_ack *extack)
1329 {
1330 	struct net_bridge_vlan_group *vg;
1331 	struct net_bridge_port *p = NULL;
1332 	struct net_bridge_vlan *v;
1333 	struct net_bridge *br;
1334 	int err;
1335 
1336 	if (netif_is_bridge_master(dev)) {
1337 		br = netdev_priv(dev);
1338 		vg = br_vlan_group(br);
1339 	} else {
1340 		p = br_port_get_rtnl(dev);
1341 		if (!p) {
1342 			pr_info("bridge: RTM_DELNEIGH %s not a bridge port\n",
1343 				dev->name);
1344 			return -EINVAL;
1345 		}
1346 		vg = nbp_vlan_group(p);
1347 		br = p->br;
1348 	}
1349 
1350 	if (vid) {
1351 		v = br_vlan_find(vg, vid);
1352 		if (!v) {
1353 			pr_info("bridge: RTM_DELNEIGH with unconfigured vlan %d on %s\n", vid, dev->name);
1354 			return -EINVAL;
1355 		}
1356 
1357 		err = __br_fdb_delete(br, p, addr, vid);
1358 	} else {
1359 		err = -ENOENT;
1360 		err &= __br_fdb_delete(br, p, addr, 0);
1361 		if (!vg || !vg->num_vlans)
1362 			return err;
1363 
1364 		list_for_each_entry(v, &vg->vlan_list, vlist) {
1365 			if (!br_vlan_should_use(v))
1366 				continue;
1367 			err &= __br_fdb_delete(br, p, addr, v->vid);
1368 		}
1369 	}
1370 
1371 	return err;
1372 }
1373 
1374 int br_fdb_sync_static(struct net_bridge *br, struct net_bridge_port *p)
1375 {
1376 	struct net_bridge_fdb_entry *f, *tmp;
1377 	int err = 0;
1378 
1379 	ASSERT_RTNL();
1380 
1381 	/* the key here is that static entries change only under rtnl */
1382 	rcu_read_lock();
1383 	hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
1384 		/* We only care for static entries */
1385 		if (!test_bit(BR_FDB_STATIC, &f->flags))
1386 			continue;
1387 		err = dev_uc_add(p->dev, f->key.addr.addr);
1388 		if (err)
1389 			goto rollback;
1390 	}
1391 done:
1392 	rcu_read_unlock();
1393 
1394 	return err;
1395 
1396 rollback:
1397 	hlist_for_each_entry_rcu(tmp, &br->fdb_list, fdb_node) {
1398 		/* We only care for static entries */
1399 		if (!test_bit(BR_FDB_STATIC, &tmp->flags))
1400 			continue;
1401 		if (tmp == f)
1402 			break;
1403 		dev_uc_del(p->dev, tmp->key.addr.addr);
1404 	}
1405 
1406 	goto done;
1407 }
1408 
1409 void br_fdb_unsync_static(struct net_bridge *br, struct net_bridge_port *p)
1410 {
1411 	struct net_bridge_fdb_entry *f;
1412 
1413 	ASSERT_RTNL();
1414 
1415 	rcu_read_lock();
1416 	hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
1417 		/* We only care for static entries */
1418 		if (!test_bit(BR_FDB_STATIC, &f->flags))
1419 			continue;
1420 
1421 		dev_uc_del(p->dev, f->key.addr.addr);
1422 	}
1423 	rcu_read_unlock();
1424 }
1425 
1426 int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p,
1427 			      const unsigned char *addr, u16 vid, bool locked,
1428 			      bool swdev_notify)
1429 {
1430 	struct net_bridge_fdb_entry *fdb;
1431 	bool modified = false;
1432 	int err = 0;
1433 
1434 	trace_br_fdb_external_learn_add(br, p, addr, vid);
1435 
1436 	if (locked && (!p || !(p->flags & BR_PORT_MAB)))
1437 		return -EINVAL;
1438 
1439 	spin_lock_bh(&br->hash_lock);
1440 
1441 	fdb = br_fdb_find(br, addr, vid);
1442 	if (!fdb) {
1443 		unsigned long flags = BIT(BR_FDB_ADDED_BY_EXT_LEARN);
1444 
1445 		if (swdev_notify)
1446 			flags |= BIT(BR_FDB_ADDED_BY_USER);
1447 
1448 		if (!p)
1449 			flags |= BIT(BR_FDB_LOCAL);
1450 
1451 		if (locked)
1452 			flags |= BIT(BR_FDB_LOCKED);
1453 
1454 		fdb = fdb_create(br, p, addr, vid, flags);
1455 		if (!fdb) {
1456 			err = -ENOMEM;
1457 			goto err_unlock;
1458 		}
1459 		fdb_notify(br, fdb, RTM_NEWNEIGH, swdev_notify);
1460 	} else {
1461 		if (locked &&
1462 		    (!test_bit(BR_FDB_LOCKED, &fdb->flags) ||
1463 		     READ_ONCE(fdb->dst) != p)) {
1464 			err = -EINVAL;
1465 			goto err_unlock;
1466 		}
1467 
1468 		fdb->updated = jiffies;
1469 
1470 		if (READ_ONCE(fdb->dst) != p) {
1471 			WRITE_ONCE(fdb->dst, p);
1472 			modified = true;
1473 		}
1474 
1475 		if (test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags)) {
1476 			/* Refresh entry */
1477 			fdb->used = jiffies;
1478 		} else if (!test_bit(BR_FDB_ADDED_BY_USER, &fdb->flags)) {
1479 			/* Take over SW learned entry */
1480 			set_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags);
1481 			modified = true;
1482 		}
1483 
1484 		if (locked != test_bit(BR_FDB_LOCKED, &fdb->flags)) {
1485 			change_bit(BR_FDB_LOCKED, &fdb->flags);
1486 			modified = true;
1487 		}
1488 
1489 		if (swdev_notify)
1490 			set_bit(BR_FDB_ADDED_BY_USER, &fdb->flags);
1491 
1492 		if (!p)
1493 			set_bit(BR_FDB_LOCAL, &fdb->flags);
1494 
1495 		if ((swdev_notify || !p) &&
1496 		    test_and_clear_bit(BR_FDB_DYNAMIC_LEARNED, &fdb->flags))
1497 			atomic_dec(&br->fdb_n_learned);
1498 
1499 		if (modified)
1500 			fdb_notify(br, fdb, RTM_NEWNEIGH, swdev_notify);
1501 	}
1502 
1503 err_unlock:
1504 	spin_unlock_bh(&br->hash_lock);
1505 
1506 	return err;
1507 }
1508 
1509 int br_fdb_external_learn_del(struct net_bridge *br, struct net_bridge_port *p,
1510 			      const unsigned char *addr, u16 vid,
1511 			      bool swdev_notify)
1512 {
1513 	struct net_bridge_fdb_entry *fdb;
1514 	int err = 0;
1515 
1516 	spin_lock_bh(&br->hash_lock);
1517 
1518 	fdb = br_fdb_find(br, addr, vid);
1519 	if (fdb && test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags))
1520 		fdb_delete(br, fdb, swdev_notify);
1521 	else
1522 		err = -ENOENT;
1523 
1524 	spin_unlock_bh(&br->hash_lock);
1525 
1526 	return err;
1527 }
1528 
1529 void br_fdb_offloaded_set(struct net_bridge *br, struct net_bridge_port *p,
1530 			  const unsigned char *addr, u16 vid, bool offloaded)
1531 {
1532 	struct net_bridge_fdb_entry *fdb;
1533 
1534 	spin_lock_bh(&br->hash_lock);
1535 
1536 	fdb = br_fdb_find(br, addr, vid);
1537 	if (fdb && offloaded != test_bit(BR_FDB_OFFLOADED, &fdb->flags))
1538 		change_bit(BR_FDB_OFFLOADED, &fdb->flags);
1539 
1540 	spin_unlock_bh(&br->hash_lock);
1541 }
1542 
1543 void br_fdb_clear_offload(const struct net_device *dev, u16 vid)
1544 {
1545 	struct net_bridge_fdb_entry *f;
1546 	struct net_bridge_port *p;
1547 
1548 	ASSERT_RTNL();
1549 
1550 	p = br_port_get_rtnl(dev);
1551 	if (!p)
1552 		return;
1553 
1554 	spin_lock_bh(&p->br->hash_lock);
1555 	hlist_for_each_entry(f, &p->br->fdb_list, fdb_node) {
1556 		if (f->dst == p && f->key.vlan_id == vid)
1557 			clear_bit(BR_FDB_OFFLOADED, &f->flags);
1558 	}
1559 	spin_unlock_bh(&p->br->hash_lock);
1560 }
1561 EXPORT_SYMBOL_GPL(br_fdb_clear_offload);
1562