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1/*
2 * Forwarding database
3 * Linux ethernet bridge
4 *
5 * Authors:
6 * Lennert Buytenhek <buytenh@gnu.org>
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; either version
11 * 2 of the License, or (at your option) any later version.
12 */
13
14#include <linux/kernel.h>
15#include <linux/init.h>
16#include <linux/rculist.h>
17#include <linux/spinlock.h>
18#include <linux/times.h>
19#include <linux/netdevice.h>
20#include <linux/etherdevice.h>
21#include <linux/jhash.h>
22#include <linux/random.h>
23#include <linux/slab.h>
24#include <linux/atomic.h>
25#include <asm/unaligned.h>
26#include <linux/if_vlan.h>
27#include <net/switchdev.h>
28#include "br_private.h"
29
30static struct kmem_cache *br_fdb_cache __read_mostly;
31static struct net_bridge_fdb_entry *fdb_find(struct hlist_head *head,
32 const unsigned char *addr,
33 __u16 vid);
34static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
35 const unsigned char *addr, u16 vid);
36static void fdb_notify(struct net_bridge *br,
37 const struct net_bridge_fdb_entry *, int);
38
39static u32 fdb_salt __read_mostly;
40
41int __init br_fdb_init(void)
42{
43 br_fdb_cache = kmem_cache_create("bridge_fdb_cache",
44 sizeof(struct net_bridge_fdb_entry),
45 0,
46 SLAB_HWCACHE_ALIGN, NULL);
47 if (!br_fdb_cache)
48 return -ENOMEM;
49
50 get_random_bytes(&fdb_salt, sizeof(fdb_salt));
51 return 0;
52}
53
54void br_fdb_fini(void)
55{
56 kmem_cache_destroy(br_fdb_cache);
57}
58
59
60/* if topology_changing then use forward_delay (default 15 sec)
61 * otherwise keep longer (default 5 minutes)
62 */
63static inline unsigned long hold_time(const struct net_bridge *br)
64{
65 return br->topology_change ? br->forward_delay : br->ageing_time;
66}
67
68static inline int has_expired(const struct net_bridge *br,
69 const struct net_bridge_fdb_entry *fdb)
70{
71 return !fdb->is_static &&
72 time_before_eq(fdb->updated + hold_time(br), jiffies);
73}
74
75static inline int br_mac_hash(const unsigned char *mac, __u16 vid)
76{
77 /* use 1 byte of OUI and 3 bytes of NIC */
78 u32 key = get_unaligned((u32 *)(mac + 2));
79 return jhash_2words(key, vid, fdb_salt) & (BR_HASH_SIZE - 1);
80}
81
82static void fdb_rcu_free(struct rcu_head *head)
83{
84 struct net_bridge_fdb_entry *ent
85 = container_of(head, struct net_bridge_fdb_entry, rcu);
86 kmem_cache_free(br_fdb_cache, ent);
87}
88
89/* When a static FDB entry is added, the mac address from the entry is
90 * added to the bridge private HW address list and all required ports
91 * are then updated with the new information.
92 * Called under RTNL.
93 */
94static void fdb_add_hw_addr(struct net_bridge *br, const unsigned char *addr)
95{
96 int err;
97 struct net_bridge_port *p;
98
99 ASSERT_RTNL();
100
101 list_for_each_entry(p, &br->port_list, list) {
102 if (!br_promisc_port(p)) {
103 err = dev_uc_add(p->dev, addr);
104 if (err)
105 goto undo;
106 }
107 }
108
109 return;
110undo:
111 list_for_each_entry_continue_reverse(p, &br->port_list, list) {
112 if (!br_promisc_port(p))
113 dev_uc_del(p->dev, addr);
114 }
115}
116
117/* When a static FDB entry is deleted, the HW address from that entry is
118 * also removed from the bridge private HW address list and updates all
119 * the ports with needed information.
120 * Called under RTNL.
121 */
122static void fdb_del_hw_addr(struct net_bridge *br, const unsigned char *addr)
123{
124 struct net_bridge_port *p;
125
126 ASSERT_RTNL();
127
128 list_for_each_entry(p, &br->port_list, list) {
129 if (!br_promisc_port(p))
130 dev_uc_del(p->dev, addr);
131 }
132}
133
134static void fdb_del_external_learn(struct net_bridge_fdb_entry *f)
135{
136 struct switchdev_obj_port_fdb fdb = {
137 .obj = {
138 .orig_dev = f->dst->dev,
139 .id = SWITCHDEV_OBJ_ID_PORT_FDB,
140 .flags = SWITCHDEV_F_DEFER,
141 },
142 .vid = f->vlan_id,
143 };
144
145 ether_addr_copy(fdb.addr, f->addr.addr);
146 switchdev_port_obj_del(f->dst->dev, &fdb.obj);
147}
148
149static void fdb_delete(struct net_bridge *br, struct net_bridge_fdb_entry *f)
150{
151 if (f->is_static)
152 fdb_del_hw_addr(br, f->addr.addr);
153
154 if (f->added_by_external_learn)
155 fdb_del_external_learn(f);
156
157 hlist_del_rcu(&f->hlist);
158 fdb_notify(br, f, RTM_DELNEIGH);
159 call_rcu(&f->rcu, fdb_rcu_free);
160}
161
162/* Delete a local entry if no other port had the same address. */
163static void fdb_delete_local(struct net_bridge *br,
164 const struct net_bridge_port *p,
165 struct net_bridge_fdb_entry *f)
166{
167 const unsigned char *addr = f->addr.addr;
168 struct net_bridge_vlan_group *vg;
169 const struct net_bridge_vlan *v;
170 struct net_bridge_port *op;
171 u16 vid = f->vlan_id;
172
173 /* Maybe another port has same hw addr? */
174 list_for_each_entry(op, &br->port_list, list) {
175 vg = nbp_vlan_group(op);
176 if (op != p && ether_addr_equal(op->dev->dev_addr, addr) &&
177 (!vid || br_vlan_find(vg, vid))) {
178 f->dst = op;
179 f->added_by_user = 0;
180 return;
181 }
182 }
183
184 vg = br_vlan_group(br);
185 v = br_vlan_find(vg, vid);
186 /* Maybe bridge device has same hw addr? */
187 if (p && ether_addr_equal(br->dev->dev_addr, addr) &&
188 (!vid || (v && br_vlan_should_use(v)))) {
189 f->dst = NULL;
190 f->added_by_user = 0;
191 return;
192 }
193
194 fdb_delete(br, f);
195}
196
197void br_fdb_find_delete_local(struct net_bridge *br,
198 const struct net_bridge_port *p,
199 const unsigned char *addr, u16 vid)
200{
201 struct hlist_head *head = &br->hash[br_mac_hash(addr, vid)];
202 struct net_bridge_fdb_entry *f;
203
204 spin_lock_bh(&br->hash_lock);
205 f = fdb_find(head, addr, vid);
206 if (f && f->is_local && !f->added_by_user && f->dst == p)
207 fdb_delete_local(br, p, f);
208 spin_unlock_bh(&br->hash_lock);
209}
210
211void br_fdb_changeaddr(struct net_bridge_port *p, const unsigned char *newaddr)
212{
213 struct net_bridge_vlan_group *vg;
214 struct net_bridge *br = p->br;
215 struct net_bridge_vlan *v;
216 int i;
217
218 spin_lock_bh(&br->hash_lock);
219
220 vg = nbp_vlan_group(p);
221 /* Search all chains since old address/hash is unknown */
222 for (i = 0; i < BR_HASH_SIZE; i++) {
223 struct hlist_node *h;
224 hlist_for_each(h, &br->hash[i]) {
225 struct net_bridge_fdb_entry *f;
226
227 f = hlist_entry(h, struct net_bridge_fdb_entry, hlist);
228 if (f->dst == p && f->is_local && !f->added_by_user) {
229 /* delete old one */
230 fdb_delete_local(br, p, f);
231
232 /* if this port has no vlan information
233 * configured, we can safely be done at
234 * this point.
235 */
236 if (!vg || !vg->num_vlans)
237 goto insert;
238 }
239 }
240 }
241
242insert:
243 /* insert new address, may fail if invalid address or dup. */
244 fdb_insert(br, p, newaddr, 0);
245
246 if (!vg || !vg->num_vlans)
247 goto done;
248
249 /* Now add entries for every VLAN configured on the port.
250 * This function runs under RTNL so the bitmap will not change
251 * from under us.
252 */
253 list_for_each_entry(v, &vg->vlan_list, vlist)
254 fdb_insert(br, p, newaddr, v->vid);
255
256done:
257 spin_unlock_bh(&br->hash_lock);
258}
259
260void br_fdb_change_mac_address(struct net_bridge *br, const u8 *newaddr)
261{
262 struct net_bridge_vlan_group *vg;
263 struct net_bridge_fdb_entry *f;
264 struct net_bridge_vlan *v;
265
266 spin_lock_bh(&br->hash_lock);
267
268 /* If old entry was unassociated with any port, then delete it. */
269 f = __br_fdb_get(br, br->dev->dev_addr, 0);
270 if (f && f->is_local && !f->dst)
271 fdb_delete_local(br, NULL, f);
272
273 fdb_insert(br, NULL, newaddr, 0);
274 vg = br_vlan_group(br);
275 if (!vg || !vg->num_vlans)
276 goto out;
277 /* Now remove and add entries for every VLAN configured on the
278 * bridge. This function runs under RTNL so the bitmap will not
279 * change from under us.
280 */
281 list_for_each_entry(v, &vg->vlan_list, vlist) {
282 f = __br_fdb_get(br, br->dev->dev_addr, v->vid);
283 if (f && f->is_local && !f->dst)
284 fdb_delete_local(br, NULL, f);
285 fdb_insert(br, NULL, newaddr, v->vid);
286 }
287out:
288 spin_unlock_bh(&br->hash_lock);
289}
290
291void br_fdb_cleanup(unsigned long _data)
292{
293 struct net_bridge *br = (struct net_bridge *)_data;
294 unsigned long delay = hold_time(br);
295 unsigned long next_timer = jiffies + br->ageing_time;
296 int i;
297
298 spin_lock(&br->hash_lock);
299 for (i = 0; i < BR_HASH_SIZE; i++) {
300 struct net_bridge_fdb_entry *f;
301 struct hlist_node *n;
302
303 hlist_for_each_entry_safe(f, n, &br->hash[i], hlist) {
304 unsigned long this_timer;
305 if (f->is_static)
306 continue;
307 if (f->added_by_external_learn)
308 continue;
309 this_timer = f->updated + delay;
310 if (time_before_eq(this_timer, jiffies))
311 fdb_delete(br, f);
312 else if (time_before(this_timer, next_timer))
313 next_timer = this_timer;
314 }
315 }
316 spin_unlock(&br->hash_lock);
317
318 mod_timer(&br->gc_timer, round_jiffies_up(next_timer));
319}
320
321/* Completely flush all dynamic entries in forwarding database.*/
322void br_fdb_flush(struct net_bridge *br)
323{
324 int i;
325
326 spin_lock_bh(&br->hash_lock);
327 for (i = 0; i < BR_HASH_SIZE; i++) {
328 struct net_bridge_fdb_entry *f;
329 struct hlist_node *n;
330 hlist_for_each_entry_safe(f, n, &br->hash[i], hlist) {
331 if (!f->is_static)
332 fdb_delete(br, f);
333 }
334 }
335 spin_unlock_bh(&br->hash_lock);
336}
337
338/* Flush all entries referring to a specific port.
339 * if do_all is set also flush static entries
340 * if vid is set delete all entries that match the vlan_id
341 */
342void br_fdb_delete_by_port(struct net_bridge *br,
343 const struct net_bridge_port *p,
344 u16 vid,
345 int do_all)
346{
347 int i;
348
349 spin_lock_bh(&br->hash_lock);
350 for (i = 0; i < BR_HASH_SIZE; i++) {
351 struct hlist_node *h, *g;
352
353 hlist_for_each_safe(h, g, &br->hash[i]) {
354 struct net_bridge_fdb_entry *f
355 = hlist_entry(h, struct net_bridge_fdb_entry, hlist);
356 if (f->dst != p)
357 continue;
358
359 if (!do_all)
360 if (f->is_static || (vid && f->vlan_id != vid))
361 continue;
362
363 if (f->is_local)
364 fdb_delete_local(br, p, f);
365 else
366 fdb_delete(br, f);
367 }
368 }
369 spin_unlock_bh(&br->hash_lock);
370}
371
372/* No locking or refcounting, assumes caller has rcu_read_lock */
373struct net_bridge_fdb_entry *__br_fdb_get(struct net_bridge *br,
374 const unsigned char *addr,
375 __u16 vid)
376{
377 struct net_bridge_fdb_entry *fdb;
378
379 hlist_for_each_entry_rcu(fdb,
380 &br->hash[br_mac_hash(addr, vid)], hlist) {
381 if (ether_addr_equal(fdb->addr.addr, addr) &&
382 fdb->vlan_id == vid) {
383 if (unlikely(has_expired(br, fdb)))
384 break;
385 return fdb;
386 }
387 }
388
389 return NULL;
390}
391
392#if IS_ENABLED(CONFIG_ATM_LANE)
393/* Interface used by ATM LANE hook to test
394 * if an addr is on some other bridge port */
395int br_fdb_test_addr(struct net_device *dev, unsigned char *addr)
396{
397 struct net_bridge_fdb_entry *fdb;
398 struct net_bridge_port *port;
399 int ret;
400
401 rcu_read_lock();
402 port = br_port_get_rcu(dev);
403 if (!port)
404 ret = 0;
405 else {
406 fdb = __br_fdb_get(port->br, addr, 0);
407 ret = fdb && fdb->dst && fdb->dst->dev != dev &&
408 fdb->dst->state == BR_STATE_FORWARDING;
409 }
410 rcu_read_unlock();
411
412 return ret;
413}
414#endif /* CONFIG_ATM_LANE */
415
416/*
417 * Fill buffer with forwarding table records in
418 * the API format.
419 */
420int br_fdb_fillbuf(struct net_bridge *br, void *buf,
421 unsigned long maxnum, unsigned long skip)
422{
423 struct __fdb_entry *fe = buf;
424 int i, num = 0;
425 struct net_bridge_fdb_entry *f;
426
427 memset(buf, 0, maxnum*sizeof(struct __fdb_entry));
428
429 rcu_read_lock();
430 for (i = 0; i < BR_HASH_SIZE; i++) {
431 hlist_for_each_entry_rcu(f, &br->hash[i], hlist) {
432 if (num >= maxnum)
433 goto out;
434
435 if (has_expired(br, f))
436 continue;
437
438 /* ignore pseudo entry for local MAC address */
439 if (!f->dst)
440 continue;
441
442 if (skip) {
443 --skip;
444 continue;
445 }
446
447 /* convert from internal format to API */
448 memcpy(fe->mac_addr, f->addr.addr, ETH_ALEN);
449
450 /* due to ABI compat need to split into hi/lo */
451 fe->port_no = f->dst->port_no;
452 fe->port_hi = f->dst->port_no >> 8;
453
454 fe->is_local = f->is_local;
455 if (!f->is_static)
456 fe->ageing_timer_value = jiffies_delta_to_clock_t(jiffies - f->updated);
457 ++fe;
458 ++num;
459 }
460 }
461
462 out:
463 rcu_read_unlock();
464
465 return num;
466}
467
468static struct net_bridge_fdb_entry *fdb_find(struct hlist_head *head,
469 const unsigned char *addr,
470 __u16 vid)
471{
472 struct net_bridge_fdb_entry *fdb;
473
474 hlist_for_each_entry(fdb, head, hlist) {
475 if (ether_addr_equal(fdb->addr.addr, addr) &&
476 fdb->vlan_id == vid)
477 return fdb;
478 }
479 return NULL;
480}
481
482static struct net_bridge_fdb_entry *fdb_find_rcu(struct hlist_head *head,
483 const unsigned char *addr,
484 __u16 vid)
485{
486 struct net_bridge_fdb_entry *fdb;
487
488 hlist_for_each_entry_rcu(fdb, head, hlist) {
489 if (ether_addr_equal(fdb->addr.addr, addr) &&
490 fdb->vlan_id == vid)
491 return fdb;
492 }
493 return NULL;
494}
495
496static struct net_bridge_fdb_entry *fdb_create(struct hlist_head *head,
497 struct net_bridge_port *source,
498 const unsigned char *addr,
499 __u16 vid,
500 unsigned char is_local,
501 unsigned char is_static)
502{
503 struct net_bridge_fdb_entry *fdb;
504
505 fdb = kmem_cache_alloc(br_fdb_cache, GFP_ATOMIC);
506 if (fdb) {
507 memcpy(fdb->addr.addr, addr, ETH_ALEN);
508 fdb->dst = source;
509 fdb->vlan_id = vid;
510 fdb->is_local = is_local;
511 fdb->is_static = is_static;
512 fdb->added_by_user = 0;
513 fdb->added_by_external_learn = 0;
514 fdb->updated = fdb->used = jiffies;
515 hlist_add_head_rcu(&fdb->hlist, head);
516 }
517 return fdb;
518}
519
520static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
521 const unsigned char *addr, u16 vid)
522{
523 struct hlist_head *head = &br->hash[br_mac_hash(addr, vid)];
524 struct net_bridge_fdb_entry *fdb;
525
526 if (!is_valid_ether_addr(addr))
527 return -EINVAL;
528
529 fdb = fdb_find(head, addr, vid);
530 if (fdb) {
531 /* it is okay to have multiple ports with same
532 * address, just use the first one.
533 */
534 if (fdb->is_local)
535 return 0;
536 br_warn(br, "adding interface %s with same address "
537 "as a received packet\n",
538 source ? source->dev->name : br->dev->name);
539 fdb_delete(br, fdb);
540 }
541
542 fdb = fdb_create(head, source, addr, vid, 1, 1);
543 if (!fdb)
544 return -ENOMEM;
545
546 fdb_add_hw_addr(br, addr);
547 fdb_notify(br, fdb, RTM_NEWNEIGH);
548 return 0;
549}
550
551/* Add entry for local address of interface */
552int br_fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
553 const unsigned char *addr, u16 vid)
554{
555 int ret;
556
557 spin_lock_bh(&br->hash_lock);
558 ret = fdb_insert(br, source, addr, vid);
559 spin_unlock_bh(&br->hash_lock);
560 return ret;
561}
562
563void br_fdb_update(struct net_bridge *br, struct net_bridge_port *source,
564 const unsigned char *addr, u16 vid, bool added_by_user)
565{
566 struct hlist_head *head = &br->hash[br_mac_hash(addr, vid)];
567 struct net_bridge_fdb_entry *fdb;
568 bool fdb_modified = false;
569
570 /* some users want to always flood. */
571 if (hold_time(br) == 0)
572 return;
573
574 /* ignore packets unless we are using this port */
575 if (!(source->state == BR_STATE_LEARNING ||
576 source->state == BR_STATE_FORWARDING))
577 return;
578
579 fdb = fdb_find_rcu(head, addr, vid);
580 if (likely(fdb)) {
581 /* attempt to update an entry for a local interface */
582 if (unlikely(fdb->is_local)) {
583 if (net_ratelimit())
584 br_warn(br, "received packet on %s with "
585 "own address as source address\n",
586 source->dev->name);
587 } else {
588 /* fastpath: update of existing entry */
589 if (unlikely(source != fdb->dst)) {
590 fdb->dst = source;
591 fdb_modified = true;
592 }
593 fdb->updated = jiffies;
594 if (unlikely(added_by_user))
595 fdb->added_by_user = 1;
596 if (unlikely(fdb_modified))
597 fdb_notify(br, fdb, RTM_NEWNEIGH);
598 }
599 } else {
600 spin_lock(&br->hash_lock);
601 if (likely(!fdb_find(head, addr, vid))) {
602 fdb = fdb_create(head, source, addr, vid, 0, 0);
603 if (fdb) {
604 if (unlikely(added_by_user))
605 fdb->added_by_user = 1;
606 fdb_notify(br, fdb, RTM_NEWNEIGH);
607 }
608 }
609 /* else we lose race and someone else inserts
610 * it first, don't bother updating
611 */
612 spin_unlock(&br->hash_lock);
613 }
614}
615
616static int fdb_to_nud(const struct net_bridge *br,
617 const struct net_bridge_fdb_entry *fdb)
618{
619 if (fdb->is_local)
620 return NUD_PERMANENT;
621 else if (fdb->is_static)
622 return NUD_NOARP;
623 else if (has_expired(br, fdb))
624 return NUD_STALE;
625 else
626 return NUD_REACHABLE;
627}
628
629static int fdb_fill_info(struct sk_buff *skb, const struct net_bridge *br,
630 const struct net_bridge_fdb_entry *fdb,
631 u32 portid, u32 seq, int type, unsigned int flags)
632{
633 unsigned long now = jiffies;
634 struct nda_cacheinfo ci;
635 struct nlmsghdr *nlh;
636 struct ndmsg *ndm;
637
638 nlh = nlmsg_put(skb, portid, seq, type, sizeof(*ndm), flags);
639 if (nlh == NULL)
640 return -EMSGSIZE;
641
642 ndm = nlmsg_data(nlh);
643 ndm->ndm_family = AF_BRIDGE;
644 ndm->ndm_pad1 = 0;
645 ndm->ndm_pad2 = 0;
646 ndm->ndm_flags = fdb->added_by_external_learn ? NTF_EXT_LEARNED : 0;
647 ndm->ndm_type = 0;
648 ndm->ndm_ifindex = fdb->dst ? fdb->dst->dev->ifindex : br->dev->ifindex;
649 ndm->ndm_state = fdb_to_nud(br, fdb);
650
651 if (nla_put(skb, NDA_LLADDR, ETH_ALEN, &fdb->addr))
652 goto nla_put_failure;
653 if (nla_put_u32(skb, NDA_MASTER, br->dev->ifindex))
654 goto nla_put_failure;
655 ci.ndm_used = jiffies_to_clock_t(now - fdb->used);
656 ci.ndm_confirmed = 0;
657 ci.ndm_updated = jiffies_to_clock_t(now - fdb->updated);
658 ci.ndm_refcnt = 0;
659 if (nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci))
660 goto nla_put_failure;
661
662 if (fdb->vlan_id && nla_put(skb, NDA_VLAN, sizeof(u16), &fdb->vlan_id))
663 goto nla_put_failure;
664
665 nlmsg_end(skb, nlh);
666 return 0;
667
668nla_put_failure:
669 nlmsg_cancel(skb, nlh);
670 return -EMSGSIZE;
671}
672
673static inline size_t fdb_nlmsg_size(void)
674{
675 return NLMSG_ALIGN(sizeof(struct ndmsg))
676 + nla_total_size(ETH_ALEN) /* NDA_LLADDR */
677 + nla_total_size(sizeof(u32)) /* NDA_MASTER */
678 + nla_total_size(sizeof(u16)) /* NDA_VLAN */
679 + nla_total_size(sizeof(struct nda_cacheinfo));
680}
681
682static void fdb_notify(struct net_bridge *br,
683 const struct net_bridge_fdb_entry *fdb, int type)
684{
685 struct net *net = dev_net(br->dev);
686 struct sk_buff *skb;
687 int err = -ENOBUFS;
688
689 skb = nlmsg_new(fdb_nlmsg_size(), GFP_ATOMIC);
690 if (skb == NULL)
691 goto errout;
692
693 err = fdb_fill_info(skb, br, fdb, 0, 0, type, 0);
694 if (err < 0) {
695 /* -EMSGSIZE implies BUG in fdb_nlmsg_size() */
696 WARN_ON(err == -EMSGSIZE);
697 kfree_skb(skb);
698 goto errout;
699 }
700 rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
701 return;
702errout:
703 rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
704}
705
706/* Dump information about entries, in response to GETNEIGH */
707int br_fdb_dump(struct sk_buff *skb,
708 struct netlink_callback *cb,
709 struct net_device *dev,
710 struct net_device *filter_dev,
711 int idx)
712{
713 struct net_bridge *br = netdev_priv(dev);
714 int i;
715
716 if (!(dev->priv_flags & IFF_EBRIDGE))
717 goto out;
718
719 if (!filter_dev)
720 idx = ndo_dflt_fdb_dump(skb, cb, dev, NULL, idx);
721
722 for (i = 0; i < BR_HASH_SIZE; i++) {
723 struct net_bridge_fdb_entry *f;
724
725 hlist_for_each_entry_rcu(f, &br->hash[i], hlist) {
726 int err;
727
728 if (idx < cb->args[0])
729 goto skip;
730
731 if (filter_dev &&
732 (!f->dst || f->dst->dev != filter_dev)) {
733 if (filter_dev != dev)
734 goto skip;
735 /* !f->dst is a special case for bridge
736 * It means the MAC belongs to the bridge
737 * Therefore need a little more filtering
738 * we only want to dump the !f->dst case
739 */
740 if (f->dst)
741 goto skip;
742 }
743 if (!filter_dev && f->dst)
744 goto skip;
745
746 err = fdb_fill_info(skb, br, f,
747 NETLINK_CB(cb->skb).portid,
748 cb->nlh->nlmsg_seq,
749 RTM_NEWNEIGH,
750 NLM_F_MULTI);
751 if (err < 0) {
752 cb->args[1] = err;
753 break;
754 }
755skip:
756 ++idx;
757 }
758 }
759
760out:
761 return idx;
762}
763
764/* Update (create or replace) forwarding database entry */
765static int fdb_add_entry(struct net_bridge_port *source, const __u8 *addr,
766 __u16 state, __u16 flags, __u16 vid)
767{
768 struct net_bridge *br = source->br;
769 struct hlist_head *head = &br->hash[br_mac_hash(addr, vid)];
770 struct net_bridge_fdb_entry *fdb;
771 bool modified = false;
772
773 /* If the port cannot learn allow only local and static entries */
774 if (!(state & NUD_PERMANENT) && !(state & NUD_NOARP) &&
775 !(source->state == BR_STATE_LEARNING ||
776 source->state == BR_STATE_FORWARDING))
777 return -EPERM;
778
779 fdb = fdb_find(head, addr, vid);
780 if (fdb == NULL) {
781 if (!(flags & NLM_F_CREATE))
782 return -ENOENT;
783
784 fdb = fdb_create(head, source, addr, vid, 0, 0);
785 if (!fdb)
786 return -ENOMEM;
787
788 modified = true;
789 } else {
790 if (flags & NLM_F_EXCL)
791 return -EEXIST;
792
793 if (fdb->dst != source) {
794 fdb->dst = source;
795 modified = true;
796 }
797 }
798
799 if (fdb_to_nud(br, fdb) != state) {
800 if (state & NUD_PERMANENT) {
801 fdb->is_local = 1;
802 if (!fdb->is_static) {
803 fdb->is_static = 1;
804 fdb_add_hw_addr(br, addr);
805 }
806 } else if (state & NUD_NOARP) {
807 fdb->is_local = 0;
808 if (!fdb->is_static) {
809 fdb->is_static = 1;
810 fdb_add_hw_addr(br, addr);
811 }
812 } else {
813 fdb->is_local = 0;
814 if (fdb->is_static) {
815 fdb->is_static = 0;
816 fdb_del_hw_addr(br, addr);
817 }
818 }
819
820 modified = true;
821 }
822 fdb->added_by_user = 1;
823
824 fdb->used = jiffies;
825 if (modified) {
826 fdb->updated = jiffies;
827 fdb_notify(br, fdb, RTM_NEWNEIGH);
828 }
829
830 return 0;
831}
832
833static int __br_fdb_add(struct ndmsg *ndm, struct net_bridge_port *p,
834 const unsigned char *addr, u16 nlh_flags, u16 vid)
835{
836 int err = 0;
837
838 if (ndm->ndm_flags & NTF_USE) {
839 local_bh_disable();
840 rcu_read_lock();
841 br_fdb_update(p->br, p, addr, vid, true);
842 rcu_read_unlock();
843 local_bh_enable();
844 } else {
845 spin_lock_bh(&p->br->hash_lock);
846 err = fdb_add_entry(p, addr, ndm->ndm_state,
847 nlh_flags, vid);
848 spin_unlock_bh(&p->br->hash_lock);
849 }
850
851 return err;
852}
853
854/* Add new permanent fdb entry with RTM_NEWNEIGH */
855int br_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
856 struct net_device *dev,
857 const unsigned char *addr, u16 vid, u16 nlh_flags)
858{
859 struct net_bridge_vlan_group *vg;
860 struct net_bridge_port *p = NULL;
861 struct net_bridge_vlan *v;
862 struct net_bridge *br = NULL;
863 int err = 0;
864
865 if (!(ndm->ndm_state & (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE))) {
866 pr_info("bridge: RTM_NEWNEIGH with invalid state %#x\n", ndm->ndm_state);
867 return -EINVAL;
868 }
869
870 if (is_zero_ether_addr(addr)) {
871 pr_info("bridge: RTM_NEWNEIGH with invalid ether address\n");
872 return -EINVAL;
873 }
874
875 if (dev->priv_flags & IFF_EBRIDGE) {
876 br = netdev_priv(dev);
877 vg = br_vlan_group(br);
878 } else {
879 p = br_port_get_rtnl(dev);
880 if (!p) {
881 pr_info("bridge: RTM_NEWNEIGH %s not a bridge port\n",
882 dev->name);
883 return -EINVAL;
884 }
885 vg = nbp_vlan_group(p);
886 }
887
888 if (vid) {
889 v = br_vlan_find(vg, vid);
890 if (!v || !br_vlan_should_use(v)) {
891 pr_info("bridge: RTM_NEWNEIGH with unconfigured vlan %d on %s\n", vid, dev->name);
892 return -EINVAL;
893 }
894
895 /* VID was specified, so use it. */
896 if (dev->priv_flags & IFF_EBRIDGE)
897 err = br_fdb_insert(br, NULL, addr, vid);
898 else
899 err = __br_fdb_add(ndm, p, addr, nlh_flags, vid);
900 } else {
901 if (dev->priv_flags & IFF_EBRIDGE)
902 err = br_fdb_insert(br, NULL, addr, 0);
903 else
904 err = __br_fdb_add(ndm, p, addr, nlh_flags, 0);
905 if (err || !vg || !vg->num_vlans)
906 goto out;
907
908 /* We have vlans configured on this port and user didn't
909 * specify a VLAN. To be nice, add/update entry for every
910 * vlan on this port.
911 */
912 list_for_each_entry(v, &vg->vlan_list, vlist) {
913 if (!br_vlan_should_use(v))
914 continue;
915 if (dev->priv_flags & IFF_EBRIDGE)
916 err = br_fdb_insert(br, NULL, addr, v->vid);
917 else
918 err = __br_fdb_add(ndm, p, addr, nlh_flags,
919 v->vid);
920 if (err)
921 goto out;
922 }
923 }
924
925out:
926 return err;
927}
928
929static int fdb_delete_by_addr(struct net_bridge *br, const u8 *addr,
930 u16 vid)
931{
932 struct hlist_head *head = &br->hash[br_mac_hash(addr, vid)];
933 struct net_bridge_fdb_entry *fdb;
934
935 fdb = fdb_find(head, addr, vid);
936 if (!fdb)
937 return -ENOENT;
938
939 fdb_delete(br, fdb);
940 return 0;
941}
942
943static int __br_fdb_delete_by_addr(struct net_bridge *br,
944 const unsigned char *addr, u16 vid)
945{
946 int err;
947
948 spin_lock_bh(&br->hash_lock);
949 err = fdb_delete_by_addr(br, addr, vid);
950 spin_unlock_bh(&br->hash_lock);
951
952 return err;
953}
954
955static int fdb_delete_by_addr_and_port(struct net_bridge_port *p,
956 const u8 *addr, u16 vlan)
957{
958 struct net_bridge *br = p->br;
959 struct hlist_head *head = &br->hash[br_mac_hash(addr, vlan)];
960 struct net_bridge_fdb_entry *fdb;
961
962 fdb = fdb_find(head, addr, vlan);
963 if (!fdb || fdb->dst != p)
964 return -ENOENT;
965
966 fdb_delete(br, fdb);
967 return 0;
968}
969
970static int __br_fdb_delete(struct net_bridge_port *p,
971 const unsigned char *addr, u16 vid)
972{
973 int err;
974
975 spin_lock_bh(&p->br->hash_lock);
976 err = fdb_delete_by_addr_and_port(p, addr, vid);
977 spin_unlock_bh(&p->br->hash_lock);
978
979 return err;
980}
981
982/* Remove neighbor entry with RTM_DELNEIGH */
983int br_fdb_delete(struct ndmsg *ndm, struct nlattr *tb[],
984 struct net_device *dev,
985 const unsigned char *addr, u16 vid)
986{
987 struct net_bridge_vlan_group *vg;
988 struct net_bridge_port *p = NULL;
989 struct net_bridge_vlan *v;
990 struct net_bridge *br = NULL;
991 int err;
992
993 if (dev->priv_flags & IFF_EBRIDGE) {
994 br = netdev_priv(dev);
995 vg = br_vlan_group(br);
996 } else {
997 p = br_port_get_rtnl(dev);
998 if (!p) {
999 pr_info("bridge: RTM_DELNEIGH %s not a bridge port\n",
1000 dev->name);
1001 return -EINVAL;
1002 }
1003 vg = nbp_vlan_group(p);
1004 }
1005
1006 if (vid) {
1007 v = br_vlan_find(vg, vid);
1008 if (!v) {
1009 pr_info("bridge: RTM_DELNEIGH with unconfigured vlan %d on %s\n", vid, dev->name);
1010 return -EINVAL;
1011 }
1012
1013 if (dev->priv_flags & IFF_EBRIDGE)
1014 err = __br_fdb_delete_by_addr(br, addr, vid);
1015 else
1016 err = __br_fdb_delete(p, addr, vid);
1017 } else {
1018 err = -ENOENT;
1019 if (dev->priv_flags & IFF_EBRIDGE)
1020 err = __br_fdb_delete_by_addr(br, addr, 0);
1021 else
1022 err &= __br_fdb_delete(p, addr, 0);
1023
1024 if (!vg || !vg->num_vlans)
1025 goto out;
1026
1027 list_for_each_entry(v, &vg->vlan_list, vlist) {
1028 if (!br_vlan_should_use(v))
1029 continue;
1030 if (dev->priv_flags & IFF_EBRIDGE)
1031 err = __br_fdb_delete_by_addr(br, addr, v->vid);
1032 else
1033 err &= __br_fdb_delete(p, addr, v->vid);
1034 }
1035 }
1036out:
1037 return err;
1038}
1039
1040int br_fdb_sync_static(struct net_bridge *br, struct net_bridge_port *p)
1041{
1042 struct net_bridge_fdb_entry *fdb, *tmp;
1043 int i;
1044 int err;
1045
1046 ASSERT_RTNL();
1047
1048 for (i = 0; i < BR_HASH_SIZE; i++) {
1049 hlist_for_each_entry(fdb, &br->hash[i], hlist) {
1050 /* We only care for static entries */
1051 if (!fdb->is_static)
1052 continue;
1053
1054 err = dev_uc_add(p->dev, fdb->addr.addr);
1055 if (err)
1056 goto rollback;
1057 }
1058 }
1059 return 0;
1060
1061rollback:
1062 for (i = 0; i < BR_HASH_SIZE; i++) {
1063 hlist_for_each_entry(tmp, &br->hash[i], hlist) {
1064 /* If we reached the fdb that failed, we can stop */
1065 if (tmp == fdb)
1066 break;
1067
1068 /* We only care for static entries */
1069 if (!tmp->is_static)
1070 continue;
1071
1072 dev_uc_del(p->dev, tmp->addr.addr);
1073 }
1074 }
1075 return err;
1076}
1077
1078void br_fdb_unsync_static(struct net_bridge *br, struct net_bridge_port *p)
1079{
1080 struct net_bridge_fdb_entry *fdb;
1081 int i;
1082
1083 ASSERT_RTNL();
1084
1085 for (i = 0; i < BR_HASH_SIZE; i++) {
1086 hlist_for_each_entry_rcu(fdb, &br->hash[i], hlist) {
1087 /* We only care for static entries */
1088 if (!fdb->is_static)
1089 continue;
1090
1091 dev_uc_del(p->dev, fdb->addr.addr);
1092 }
1093 }
1094}
1095
1096int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p,
1097 const unsigned char *addr, u16 vid)
1098{
1099 struct hlist_head *head;
1100 struct net_bridge_fdb_entry *fdb;
1101 int err = 0;
1102
1103 ASSERT_RTNL();
1104 spin_lock_bh(&br->hash_lock);
1105
1106 head = &br->hash[br_mac_hash(addr, vid)];
1107 fdb = fdb_find(head, addr, vid);
1108 if (!fdb) {
1109 fdb = fdb_create(head, p, addr, vid, 0, 0);
1110 if (!fdb) {
1111 err = -ENOMEM;
1112 goto err_unlock;
1113 }
1114 fdb->added_by_external_learn = 1;
1115 fdb_notify(br, fdb, RTM_NEWNEIGH);
1116 } else if (fdb->added_by_external_learn) {
1117 /* Refresh entry */
1118 fdb->updated = fdb->used = jiffies;
1119 } else if (!fdb->added_by_user) {
1120 /* Take over SW learned entry */
1121 fdb->added_by_external_learn = 1;
1122 fdb->updated = jiffies;
1123 fdb_notify(br, fdb, RTM_NEWNEIGH);
1124 }
1125
1126err_unlock:
1127 spin_unlock_bh(&br->hash_lock);
1128
1129 return err;
1130}
1131
1132int br_fdb_external_learn_del(struct net_bridge *br, struct net_bridge_port *p,
1133 const unsigned char *addr, u16 vid)
1134{
1135 struct hlist_head *head;
1136 struct net_bridge_fdb_entry *fdb;
1137 int err = 0;
1138
1139 ASSERT_RTNL();
1140 spin_lock_bh(&br->hash_lock);
1141
1142 head = &br->hash[br_mac_hash(addr, vid)];
1143 fdb = fdb_find(head, addr, vid);
1144 if (fdb && fdb->added_by_external_learn)
1145 fdb_delete(br, fdb);
1146 else
1147 err = -ENOENT;
1148
1149 spin_unlock_bh(&br->hash_lock);
1150
1151 return err;
1152}
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Forwarding database
4 * Linux ethernet bridge
5 *
6 * Authors:
7 * Lennert Buytenhek <buytenh@gnu.org>
8 */
9
10#include <linux/kernel.h>
11#include <linux/init.h>
12#include <linux/rculist.h>
13#include <linux/spinlock.h>
14#include <linux/times.h>
15#include <linux/netdevice.h>
16#include <linux/etherdevice.h>
17#include <linux/jhash.h>
18#include <linux/random.h>
19#include <linux/slab.h>
20#include <linux/atomic.h>
21#include <asm/unaligned.h>
22#include <linux/if_vlan.h>
23#include <net/switchdev.h>
24#include <trace/events/bridge.h>
25#include "br_private.h"
26
27static const struct rhashtable_params br_fdb_rht_params = {
28 .head_offset = offsetof(struct net_bridge_fdb_entry, rhnode),
29 .key_offset = offsetof(struct net_bridge_fdb_entry, key),
30 .key_len = sizeof(struct net_bridge_fdb_key),
31 .automatic_shrinking = true,
32};
33
34static struct kmem_cache *br_fdb_cache __read_mostly;
35
36int __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
48void br_fdb_fini(void)
49{
50 kmem_cache_destroy(br_fdb_cache);
51}
52
53int br_fdb_hash_init(struct net_bridge *br)
54{
55 return rhashtable_init(&br->fdb_hash_tbl, &br_fdb_rht_params);
56}
57
58void 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 */
66static inline unsigned long hold_time(const struct net_bridge *br)
67{
68 return br->topology_change ? br->forward_delay : br->ageing_time;
69}
70
71static 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
79static 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
86static 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
99static 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
170nla_put_failure:
171 nlmsg_cancel(skb, nlh);
172 return -EMSGSIZE;
173}
174
175static 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
187static 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;
211errout:
212 rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
213}
214
215static 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 */
230static 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
245struct 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}
267EXPORT_SYMBOL_GPL(br_fdb_find_port);
268
269struct 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 */
281static 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;
297undo:
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 */
309static 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
321static 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 */
344static 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
378void 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
392static 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
436static 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
466void 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
490insert:
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
504done:
505 spin_unlock_bh(&br->hash_lock);
506}
507
508void 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 }
539out:
540 spin_unlock_bh(&br->hash_lock);
541}
542
543void 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
589static 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 */
607void 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
625static 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
637static 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
653static 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
685static 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
692int 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 */
769void 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 */
800int 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 */
830int 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 */
875int 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 */
887static 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
893void 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 */
962int 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;
1006skip:
1007 *idx += 1;
1008 }
1009 rcu_read_unlock();
1010
1011 return err;
1012}
1013
1014int 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);
1035errout:
1036 rcu_read_unlock();
1037 return err;
1038}
1039
1040/* returns true if the fdb is modified */
1041static 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 */
1065static 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
1162static 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
1199static 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 */
1205int 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
1292out:
1293 return err;
1294}
1295
1296static 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
1311static 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 */
1325int 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
1374int 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 }
1391done:
1392 rcu_read_unlock();
1393
1394 return err;
1395
1396rollback:
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
1409void 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
1426int 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
1503err_unlock:
1504 spin_unlock_bh(&br->hash_lock);
1505
1506 return err;
1507}
1508
1509int 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
1529void 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
1543void 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}
1561EXPORT_SYMBOL_GPL(br_fdb_clear_offload);