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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 <trace/events/bridge.h>
29#include "br_private.h"
30
31static const struct rhashtable_params br_fdb_rht_params = {
32 .head_offset = offsetof(struct net_bridge_fdb_entry, rhnode),
33 .key_offset = offsetof(struct net_bridge_fdb_entry, key),
34 .key_len = sizeof(struct net_bridge_fdb_key),
35 .automatic_shrinking = true,
36 .locks_mul = 1,
37};
38
39static struct kmem_cache *br_fdb_cache __read_mostly;
40static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
41 const unsigned char *addr, u16 vid);
42static void fdb_notify(struct net_bridge *br,
43 const struct net_bridge_fdb_entry *, int);
44
45int __init br_fdb_init(void)
46{
47 br_fdb_cache = kmem_cache_create("bridge_fdb_cache",
48 sizeof(struct net_bridge_fdb_entry),
49 0,
50 SLAB_HWCACHE_ALIGN, NULL);
51 if (!br_fdb_cache)
52 return -ENOMEM;
53
54 return 0;
55}
56
57void br_fdb_fini(void)
58{
59 kmem_cache_destroy(br_fdb_cache);
60}
61
62int br_fdb_hash_init(struct net_bridge *br)
63{
64 return rhashtable_init(&br->fdb_hash_tbl, &br_fdb_rht_params);
65}
66
67void br_fdb_hash_fini(struct net_bridge *br)
68{
69 rhashtable_destroy(&br->fdb_hash_tbl);
70}
71
72/* if topology_changing then use forward_delay (default 15 sec)
73 * otherwise keep longer (default 5 minutes)
74 */
75static inline unsigned long hold_time(const struct net_bridge *br)
76{
77 return br->topology_change ? br->forward_delay : br->ageing_time;
78}
79
80static inline int has_expired(const struct net_bridge *br,
81 const struct net_bridge_fdb_entry *fdb)
82{
83 return !fdb->is_static && !fdb->added_by_external_learn &&
84 time_before_eq(fdb->updated + hold_time(br), jiffies);
85}
86
87static void fdb_rcu_free(struct rcu_head *head)
88{
89 struct net_bridge_fdb_entry *ent
90 = container_of(head, struct net_bridge_fdb_entry, rcu);
91 kmem_cache_free(br_fdb_cache, ent);
92}
93
94static struct net_bridge_fdb_entry *fdb_find_rcu(struct rhashtable *tbl,
95 const unsigned char *addr,
96 __u16 vid)
97{
98 struct net_bridge_fdb_key key;
99
100 WARN_ON_ONCE(!rcu_read_lock_held());
101
102 key.vlan_id = vid;
103 memcpy(key.addr.addr, addr, sizeof(key.addr.addr));
104
105 return rhashtable_lookup(tbl, &key, br_fdb_rht_params);
106}
107
108/* requires bridge hash_lock */
109static struct net_bridge_fdb_entry *br_fdb_find(struct net_bridge *br,
110 const unsigned char *addr,
111 __u16 vid)
112{
113 struct net_bridge_fdb_entry *fdb;
114
115 lockdep_assert_held_once(&br->hash_lock);
116
117 rcu_read_lock();
118 fdb = fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
119 rcu_read_unlock();
120
121 return fdb;
122}
123
124struct net_bridge_fdb_entry *br_fdb_find_rcu(struct net_bridge *br,
125 const unsigned char *addr,
126 __u16 vid)
127{
128 return fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
129}
130
131/* When a static FDB entry is added, the mac address from the entry is
132 * added to the bridge private HW address list and all required ports
133 * are then updated with the new information.
134 * Called under RTNL.
135 */
136static void fdb_add_hw_addr(struct net_bridge *br, const unsigned char *addr)
137{
138 int err;
139 struct net_bridge_port *p;
140
141 ASSERT_RTNL();
142
143 list_for_each_entry(p, &br->port_list, list) {
144 if (!br_promisc_port(p)) {
145 err = dev_uc_add(p->dev, addr);
146 if (err)
147 goto undo;
148 }
149 }
150
151 return;
152undo:
153 list_for_each_entry_continue_reverse(p, &br->port_list, list) {
154 if (!br_promisc_port(p))
155 dev_uc_del(p->dev, addr);
156 }
157}
158
159/* When a static FDB entry is deleted, the HW address from that entry is
160 * also removed from the bridge private HW address list and updates all
161 * the ports with needed information.
162 * Called under RTNL.
163 */
164static void fdb_del_hw_addr(struct net_bridge *br, const unsigned char *addr)
165{
166 struct net_bridge_port *p;
167
168 ASSERT_RTNL();
169
170 list_for_each_entry(p, &br->port_list, list) {
171 if (!br_promisc_port(p))
172 dev_uc_del(p->dev, addr);
173 }
174}
175
176static void fdb_delete(struct net_bridge *br, struct net_bridge_fdb_entry *f)
177{
178 trace_fdb_delete(br, f);
179
180 if (f->is_static)
181 fdb_del_hw_addr(br, f->key.addr.addr);
182
183 hlist_del_init_rcu(&f->fdb_node);
184 rhashtable_remove_fast(&br->fdb_hash_tbl, &f->rhnode,
185 br_fdb_rht_params);
186 fdb_notify(br, f, RTM_DELNEIGH);
187 call_rcu(&f->rcu, fdb_rcu_free);
188}
189
190/* Delete a local entry if no other port had the same address. */
191static void fdb_delete_local(struct net_bridge *br,
192 const struct net_bridge_port *p,
193 struct net_bridge_fdb_entry *f)
194{
195 const unsigned char *addr = f->key.addr.addr;
196 struct net_bridge_vlan_group *vg;
197 const struct net_bridge_vlan *v;
198 struct net_bridge_port *op;
199 u16 vid = f->key.vlan_id;
200
201 /* Maybe another port has same hw addr? */
202 list_for_each_entry(op, &br->port_list, list) {
203 vg = nbp_vlan_group(op);
204 if (op != p && ether_addr_equal(op->dev->dev_addr, addr) &&
205 (!vid || br_vlan_find(vg, vid))) {
206 f->dst = op;
207 f->added_by_user = 0;
208 return;
209 }
210 }
211
212 vg = br_vlan_group(br);
213 v = br_vlan_find(vg, vid);
214 /* Maybe bridge device has same hw addr? */
215 if (p && ether_addr_equal(br->dev->dev_addr, addr) &&
216 (!vid || (v && br_vlan_should_use(v)))) {
217 f->dst = NULL;
218 f->added_by_user = 0;
219 return;
220 }
221
222 fdb_delete(br, f);
223}
224
225void br_fdb_find_delete_local(struct net_bridge *br,
226 const struct net_bridge_port *p,
227 const unsigned char *addr, u16 vid)
228{
229 struct net_bridge_fdb_entry *f;
230
231 spin_lock_bh(&br->hash_lock);
232 f = br_fdb_find(br, addr, vid);
233 if (f && f->is_local && !f->added_by_user && f->dst == p)
234 fdb_delete_local(br, p, f);
235 spin_unlock_bh(&br->hash_lock);
236}
237
238void br_fdb_changeaddr(struct net_bridge_port *p, const unsigned char *newaddr)
239{
240 struct net_bridge_vlan_group *vg;
241 struct net_bridge_fdb_entry *f;
242 struct net_bridge *br = p->br;
243 struct net_bridge_vlan *v;
244
245 spin_lock_bh(&br->hash_lock);
246 vg = nbp_vlan_group(p);
247 hlist_for_each_entry(f, &br->fdb_list, fdb_node) {
248 if (f->dst == p && f->is_local && !f->added_by_user) {
249 /* delete old one */
250 fdb_delete_local(br, p, f);
251
252 /* if this port has no vlan information
253 * configured, we can safely be done at
254 * this point.
255 */
256 if (!vg || !vg->num_vlans)
257 goto insert;
258 }
259 }
260
261insert:
262 /* insert new address, may fail if invalid address or dup. */
263 fdb_insert(br, p, newaddr, 0);
264
265 if (!vg || !vg->num_vlans)
266 goto done;
267
268 /* Now add entries for every VLAN configured on the port.
269 * This function runs under RTNL so the bitmap will not change
270 * from under us.
271 */
272 list_for_each_entry(v, &vg->vlan_list, vlist)
273 fdb_insert(br, p, newaddr, v->vid);
274
275done:
276 spin_unlock_bh(&br->hash_lock);
277}
278
279void br_fdb_change_mac_address(struct net_bridge *br, const u8 *newaddr)
280{
281 struct net_bridge_vlan_group *vg;
282 struct net_bridge_fdb_entry *f;
283 struct net_bridge_vlan *v;
284
285 spin_lock_bh(&br->hash_lock);
286
287 /* If old entry was unassociated with any port, then delete it. */
288 f = br_fdb_find(br, br->dev->dev_addr, 0);
289 if (f && f->is_local && !f->dst && !f->added_by_user)
290 fdb_delete_local(br, NULL, f);
291
292 fdb_insert(br, NULL, newaddr, 0);
293 vg = br_vlan_group(br);
294 if (!vg || !vg->num_vlans)
295 goto out;
296 /* Now remove and add entries for every VLAN configured on the
297 * bridge. This function runs under RTNL so the bitmap will not
298 * change from under us.
299 */
300 list_for_each_entry(v, &vg->vlan_list, vlist) {
301 if (!br_vlan_should_use(v))
302 continue;
303 f = br_fdb_find(br, br->dev->dev_addr, v->vid);
304 if (f && f->is_local && !f->dst && !f->added_by_user)
305 fdb_delete_local(br, NULL, f);
306 fdb_insert(br, NULL, newaddr, v->vid);
307 }
308out:
309 spin_unlock_bh(&br->hash_lock);
310}
311
312void br_fdb_cleanup(struct work_struct *work)
313{
314 struct net_bridge *br = container_of(work, struct net_bridge,
315 gc_work.work);
316 struct net_bridge_fdb_entry *f = NULL;
317 unsigned long delay = hold_time(br);
318 unsigned long work_delay = delay;
319 unsigned long now = jiffies;
320
321 /* this part is tricky, in order to avoid blocking learning and
322 * consequently forwarding, we rely on rcu to delete objects with
323 * delayed freeing allowing us to continue traversing
324 */
325 rcu_read_lock();
326 hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
327 unsigned long this_timer;
328
329 if (f->is_static || f->added_by_external_learn)
330 continue;
331 this_timer = f->updated + delay;
332 if (time_after(this_timer, now)) {
333 work_delay = min(work_delay, this_timer - now);
334 } else {
335 spin_lock_bh(&br->hash_lock);
336 if (!hlist_unhashed(&f->fdb_node))
337 fdb_delete(br, f);
338 spin_unlock_bh(&br->hash_lock);
339 }
340 }
341 rcu_read_unlock();
342
343 /* Cleanup minimum 10 milliseconds apart */
344 work_delay = max_t(unsigned long, work_delay, msecs_to_jiffies(10));
345 mod_delayed_work(system_long_wq, &br->gc_work, work_delay);
346}
347
348/* Completely flush all dynamic entries in forwarding database.*/
349void br_fdb_flush(struct net_bridge *br)
350{
351 struct net_bridge_fdb_entry *f;
352 struct hlist_node *tmp;
353
354 spin_lock_bh(&br->hash_lock);
355 hlist_for_each_entry_safe(f, tmp, &br->fdb_list, fdb_node) {
356 if (!f->is_static)
357 fdb_delete(br, f);
358 }
359 spin_unlock_bh(&br->hash_lock);
360}
361
362/* Flush all entries referring to a specific port.
363 * if do_all is set also flush static entries
364 * if vid is set delete all entries that match the vlan_id
365 */
366void br_fdb_delete_by_port(struct net_bridge *br,
367 const struct net_bridge_port *p,
368 u16 vid,
369 int do_all)
370{
371 struct net_bridge_fdb_entry *f;
372 struct hlist_node *tmp;
373
374 spin_lock_bh(&br->hash_lock);
375 hlist_for_each_entry_safe(f, tmp, &br->fdb_list, fdb_node) {
376 if (f->dst != p)
377 continue;
378
379 if (!do_all)
380 if (f->is_static || (vid && f->key.vlan_id != vid))
381 continue;
382
383 if (f->is_local)
384 fdb_delete_local(br, p, f);
385 else
386 fdb_delete(br, f);
387 }
388 spin_unlock_bh(&br->hash_lock);
389}
390
391#if IS_ENABLED(CONFIG_ATM_LANE)
392/* Interface used by ATM LANE hook to test
393 * if an addr is on some other bridge port */
394int br_fdb_test_addr(struct net_device *dev, unsigned char *addr)
395{
396 struct net_bridge_fdb_entry *fdb;
397 struct net_bridge_port *port;
398 int ret;
399
400 rcu_read_lock();
401 port = br_port_get_rcu(dev);
402 if (!port)
403 ret = 0;
404 else {
405 fdb = br_fdb_find_rcu(port->br, addr, 0);
406 ret = fdb && fdb->dst && fdb->dst->dev != dev &&
407 fdb->dst->state == BR_STATE_FORWARDING;
408 }
409 rcu_read_unlock();
410
411 return ret;
412}
413#endif /* CONFIG_ATM_LANE */
414
415/*
416 * Fill buffer with forwarding table records in
417 * the API format.
418 */
419int br_fdb_fillbuf(struct net_bridge *br, void *buf,
420 unsigned long maxnum, unsigned long skip)
421{
422 struct net_bridge_fdb_entry *f;
423 struct __fdb_entry *fe = buf;
424 int num = 0;
425
426 memset(buf, 0, maxnum*sizeof(struct __fdb_entry));
427
428 rcu_read_lock();
429 hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
430 if (num >= maxnum)
431 break;
432
433 if (has_expired(br, f))
434 continue;
435
436 /* ignore pseudo entry for local MAC address */
437 if (!f->dst)
438 continue;
439
440 if (skip) {
441 --skip;
442 continue;
443 }
444
445 /* convert from internal format to API */
446 memcpy(fe->mac_addr, f->key.addr.addr, ETH_ALEN);
447
448 /* due to ABI compat need to split into hi/lo */
449 fe->port_no = f->dst->port_no;
450 fe->port_hi = f->dst->port_no >> 8;
451
452 fe->is_local = f->is_local;
453 if (!f->is_static)
454 fe->ageing_timer_value = jiffies_delta_to_clock_t(jiffies - f->updated);
455 ++fe;
456 ++num;
457 }
458 rcu_read_unlock();
459
460 return num;
461}
462
463static struct net_bridge_fdb_entry *fdb_create(struct net_bridge *br,
464 struct net_bridge_port *source,
465 const unsigned char *addr,
466 __u16 vid,
467 unsigned char is_local,
468 unsigned char is_static)
469{
470 struct net_bridge_fdb_entry *fdb;
471
472 fdb = kmem_cache_alloc(br_fdb_cache, GFP_ATOMIC);
473 if (fdb) {
474 memcpy(fdb->key.addr.addr, addr, ETH_ALEN);
475 fdb->dst = source;
476 fdb->key.vlan_id = vid;
477 fdb->is_local = is_local;
478 fdb->is_static = is_static;
479 fdb->added_by_user = 0;
480 fdb->added_by_external_learn = 0;
481 fdb->offloaded = 0;
482 fdb->updated = fdb->used = jiffies;
483 if (rhashtable_lookup_insert_fast(&br->fdb_hash_tbl,
484 &fdb->rhnode,
485 br_fdb_rht_params)) {
486 kmem_cache_free(br_fdb_cache, fdb);
487 fdb = NULL;
488 } else {
489 hlist_add_head_rcu(&fdb->fdb_node, &br->fdb_list);
490 }
491 }
492 return fdb;
493}
494
495static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
496 const unsigned char *addr, u16 vid)
497{
498 struct net_bridge_fdb_entry *fdb;
499
500 if (!is_valid_ether_addr(addr))
501 return -EINVAL;
502
503 fdb = br_fdb_find(br, addr, vid);
504 if (fdb) {
505 /* it is okay to have multiple ports with same
506 * address, just use the first one.
507 */
508 if (fdb->is_local)
509 return 0;
510 br_warn(br, "adding interface %s with same address as a received packet (addr:%pM, vlan:%u)\n",
511 source ? source->dev->name : br->dev->name, addr, vid);
512 fdb_delete(br, fdb);
513 }
514
515 fdb = fdb_create(br, source, addr, vid, 1, 1);
516 if (!fdb)
517 return -ENOMEM;
518
519 fdb_add_hw_addr(br, addr);
520 fdb_notify(br, fdb, RTM_NEWNEIGH);
521 return 0;
522}
523
524/* Add entry for local address of interface */
525int br_fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
526 const unsigned char *addr, u16 vid)
527{
528 int ret;
529
530 spin_lock_bh(&br->hash_lock);
531 ret = fdb_insert(br, source, addr, vid);
532 spin_unlock_bh(&br->hash_lock);
533 return ret;
534}
535
536void br_fdb_update(struct net_bridge *br, struct net_bridge_port *source,
537 const unsigned char *addr, u16 vid, bool added_by_user)
538{
539 struct net_bridge_fdb_entry *fdb;
540 bool fdb_modified = false;
541
542 /* some users want to always flood. */
543 if (hold_time(br) == 0)
544 return;
545
546 /* ignore packets unless we are using this port */
547 if (!(source->state == BR_STATE_LEARNING ||
548 source->state == BR_STATE_FORWARDING))
549 return;
550
551 fdb = fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
552 if (likely(fdb)) {
553 /* attempt to update an entry for a local interface */
554 if (unlikely(fdb->is_local)) {
555 if (net_ratelimit())
556 br_warn(br, "received packet on %s with own address as source address (addr:%pM, vlan:%u)\n",
557 source->dev->name, addr, vid);
558 } else {
559 unsigned long now = jiffies;
560
561 /* fastpath: update of existing entry */
562 if (unlikely(source != fdb->dst)) {
563 fdb->dst = source;
564 fdb_modified = true;
565 /* Take over HW learned entry */
566 if (unlikely(fdb->added_by_external_learn))
567 fdb->added_by_external_learn = 0;
568 }
569 if (now != fdb->updated)
570 fdb->updated = now;
571 if (unlikely(added_by_user))
572 fdb->added_by_user = 1;
573 if (unlikely(fdb_modified)) {
574 trace_br_fdb_update(br, source, addr, vid, added_by_user);
575 fdb_notify(br, fdb, RTM_NEWNEIGH);
576 }
577 }
578 } else {
579 spin_lock(&br->hash_lock);
580 fdb = fdb_create(br, source, addr, vid, 0, 0);
581 if (fdb) {
582 if (unlikely(added_by_user))
583 fdb->added_by_user = 1;
584 trace_br_fdb_update(br, source, addr, vid,
585 added_by_user);
586 fdb_notify(br, fdb, RTM_NEWNEIGH);
587 }
588 /* else we lose race and someone else inserts
589 * it first, don't bother updating
590 */
591 spin_unlock(&br->hash_lock);
592 }
593}
594
595static int fdb_to_nud(const struct net_bridge *br,
596 const struct net_bridge_fdb_entry *fdb)
597{
598 if (fdb->is_local)
599 return NUD_PERMANENT;
600 else if (fdb->is_static)
601 return NUD_NOARP;
602 else if (has_expired(br, fdb))
603 return NUD_STALE;
604 else
605 return NUD_REACHABLE;
606}
607
608static int fdb_fill_info(struct sk_buff *skb, const struct net_bridge *br,
609 const struct net_bridge_fdb_entry *fdb,
610 u32 portid, u32 seq, int type, unsigned int flags)
611{
612 unsigned long now = jiffies;
613 struct nda_cacheinfo ci;
614 struct nlmsghdr *nlh;
615 struct ndmsg *ndm;
616
617 nlh = nlmsg_put(skb, portid, seq, type, sizeof(*ndm), flags);
618 if (nlh == NULL)
619 return -EMSGSIZE;
620
621 ndm = nlmsg_data(nlh);
622 ndm->ndm_family = AF_BRIDGE;
623 ndm->ndm_pad1 = 0;
624 ndm->ndm_pad2 = 0;
625 ndm->ndm_flags = 0;
626 ndm->ndm_type = 0;
627 ndm->ndm_ifindex = fdb->dst ? fdb->dst->dev->ifindex : br->dev->ifindex;
628 ndm->ndm_state = fdb_to_nud(br, fdb);
629
630 if (fdb->offloaded)
631 ndm->ndm_flags |= NTF_OFFLOADED;
632 if (fdb->added_by_external_learn)
633 ndm->ndm_flags |= NTF_EXT_LEARNED;
634
635 if (nla_put(skb, NDA_LLADDR, ETH_ALEN, &fdb->key.addr))
636 goto nla_put_failure;
637 if (nla_put_u32(skb, NDA_MASTER, br->dev->ifindex))
638 goto nla_put_failure;
639 ci.ndm_used = jiffies_to_clock_t(now - fdb->used);
640 ci.ndm_confirmed = 0;
641 ci.ndm_updated = jiffies_to_clock_t(now - fdb->updated);
642 ci.ndm_refcnt = 0;
643 if (nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci))
644 goto nla_put_failure;
645
646 if (fdb->key.vlan_id && nla_put(skb, NDA_VLAN, sizeof(u16),
647 &fdb->key.vlan_id))
648 goto nla_put_failure;
649
650 nlmsg_end(skb, nlh);
651 return 0;
652
653nla_put_failure:
654 nlmsg_cancel(skb, nlh);
655 return -EMSGSIZE;
656}
657
658static inline size_t fdb_nlmsg_size(void)
659{
660 return NLMSG_ALIGN(sizeof(struct ndmsg))
661 + nla_total_size(ETH_ALEN) /* NDA_LLADDR */
662 + nla_total_size(sizeof(u32)) /* NDA_MASTER */
663 + nla_total_size(sizeof(u16)) /* NDA_VLAN */
664 + nla_total_size(sizeof(struct nda_cacheinfo));
665}
666
667static void fdb_notify(struct net_bridge *br,
668 const struct net_bridge_fdb_entry *fdb, int type)
669{
670 struct net *net = dev_net(br->dev);
671 struct sk_buff *skb;
672 int err = -ENOBUFS;
673
674 br_switchdev_fdb_notify(fdb, type);
675
676 skb = nlmsg_new(fdb_nlmsg_size(), GFP_ATOMIC);
677 if (skb == NULL)
678 goto errout;
679
680 err = fdb_fill_info(skb, br, fdb, 0, 0, type, 0);
681 if (err < 0) {
682 /* -EMSGSIZE implies BUG in fdb_nlmsg_size() */
683 WARN_ON(err == -EMSGSIZE);
684 kfree_skb(skb);
685 goto errout;
686 }
687 rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
688 return;
689errout:
690 rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
691}
692
693/* Dump information about entries, in response to GETNEIGH */
694int br_fdb_dump(struct sk_buff *skb,
695 struct netlink_callback *cb,
696 struct net_device *dev,
697 struct net_device *filter_dev,
698 int *idx)
699{
700 struct net_bridge *br = netdev_priv(dev);
701 struct net_bridge_fdb_entry *f;
702 int err = 0;
703
704 if (!(dev->priv_flags & IFF_EBRIDGE))
705 return err;
706
707 if (!filter_dev) {
708 err = ndo_dflt_fdb_dump(skb, cb, dev, NULL, idx);
709 if (err < 0)
710 return err;
711 }
712
713 rcu_read_lock();
714 hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
715 if (*idx < cb->args[2])
716 goto skip;
717 if (filter_dev && (!f->dst || f->dst->dev != filter_dev)) {
718 if (filter_dev != dev)
719 goto skip;
720 /* !f->dst is a special case for bridge
721 * It means the MAC belongs to the bridge
722 * Therefore need a little more filtering
723 * we only want to dump the !f->dst case
724 */
725 if (f->dst)
726 goto skip;
727 }
728 if (!filter_dev && f->dst)
729 goto skip;
730
731 err = fdb_fill_info(skb, br, f,
732 NETLINK_CB(cb->skb).portid,
733 cb->nlh->nlmsg_seq,
734 RTM_NEWNEIGH,
735 NLM_F_MULTI);
736 if (err < 0)
737 break;
738skip:
739 *idx += 1;
740 }
741 rcu_read_unlock();
742
743 return err;
744}
745
746/* Update (create or replace) forwarding database entry */
747static int fdb_add_entry(struct net_bridge *br, struct net_bridge_port *source,
748 const __u8 *addr, __u16 state, __u16 flags, __u16 vid)
749{
750 struct net_bridge_fdb_entry *fdb;
751 bool modified = false;
752
753 /* If the port cannot learn allow only local and static entries */
754 if (source && !(state & NUD_PERMANENT) && !(state & NUD_NOARP) &&
755 !(source->state == BR_STATE_LEARNING ||
756 source->state == BR_STATE_FORWARDING))
757 return -EPERM;
758
759 if (!source && !(state & NUD_PERMANENT)) {
760 pr_info("bridge: RTM_NEWNEIGH %s without NUD_PERMANENT\n",
761 br->dev->name);
762 return -EINVAL;
763 }
764
765 fdb = br_fdb_find(br, addr, vid);
766 if (fdb == NULL) {
767 if (!(flags & NLM_F_CREATE))
768 return -ENOENT;
769
770 fdb = fdb_create(br, source, addr, vid, 0, 0);
771 if (!fdb)
772 return -ENOMEM;
773
774 modified = true;
775 } else {
776 if (flags & NLM_F_EXCL)
777 return -EEXIST;
778
779 if (fdb->dst != source) {
780 fdb->dst = source;
781 modified = true;
782 }
783 }
784
785 if (fdb_to_nud(br, fdb) != state) {
786 if (state & NUD_PERMANENT) {
787 fdb->is_local = 1;
788 if (!fdb->is_static) {
789 fdb->is_static = 1;
790 fdb_add_hw_addr(br, addr);
791 }
792 } else if (state & NUD_NOARP) {
793 fdb->is_local = 0;
794 if (!fdb->is_static) {
795 fdb->is_static = 1;
796 fdb_add_hw_addr(br, addr);
797 }
798 } else {
799 fdb->is_local = 0;
800 if (fdb->is_static) {
801 fdb->is_static = 0;
802 fdb_del_hw_addr(br, addr);
803 }
804 }
805
806 modified = true;
807 }
808 fdb->added_by_user = 1;
809
810 fdb->used = jiffies;
811 if (modified) {
812 fdb->updated = jiffies;
813 fdb_notify(br, fdb, RTM_NEWNEIGH);
814 }
815
816 return 0;
817}
818
819static int __br_fdb_add(struct ndmsg *ndm, struct net_bridge *br,
820 struct net_bridge_port *p, const unsigned char *addr,
821 u16 nlh_flags, u16 vid)
822{
823 int err = 0;
824
825 if (ndm->ndm_flags & NTF_USE) {
826 if (!p) {
827 pr_info("bridge: RTM_NEWNEIGH %s with NTF_USE is not supported\n",
828 br->dev->name);
829 return -EINVAL;
830 }
831 local_bh_disable();
832 rcu_read_lock();
833 br_fdb_update(br, p, addr, vid, true);
834 rcu_read_unlock();
835 local_bh_enable();
836 } else if (ndm->ndm_flags & NTF_EXT_LEARNED) {
837 err = br_fdb_external_learn_add(br, p, addr, vid);
838 } else {
839 spin_lock_bh(&br->hash_lock);
840 err = fdb_add_entry(br, p, addr, ndm->ndm_state,
841 nlh_flags, vid);
842 spin_unlock_bh(&br->hash_lock);
843 }
844
845 return err;
846}
847
848/* Add new permanent fdb entry with RTM_NEWNEIGH */
849int br_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
850 struct net_device *dev,
851 const unsigned char *addr, u16 vid, u16 nlh_flags)
852{
853 struct net_bridge_vlan_group *vg;
854 struct net_bridge_port *p = NULL;
855 struct net_bridge_vlan *v;
856 struct net_bridge *br = NULL;
857 int err = 0;
858
859 trace_br_fdb_add(ndm, dev, addr, vid, nlh_flags);
860
861 if (!(ndm->ndm_state & (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE))) {
862 pr_info("bridge: RTM_NEWNEIGH with invalid state %#x\n", ndm->ndm_state);
863 return -EINVAL;
864 }
865
866 if (is_zero_ether_addr(addr)) {
867 pr_info("bridge: RTM_NEWNEIGH with invalid ether address\n");
868 return -EINVAL;
869 }
870
871 if (dev->priv_flags & IFF_EBRIDGE) {
872 br = netdev_priv(dev);
873 vg = br_vlan_group(br);
874 } else {
875 p = br_port_get_rtnl(dev);
876 if (!p) {
877 pr_info("bridge: RTM_NEWNEIGH %s not a bridge port\n",
878 dev->name);
879 return -EINVAL;
880 }
881 br = p->br;
882 vg = nbp_vlan_group(p);
883 }
884
885 if (vid) {
886 v = br_vlan_find(vg, vid);
887 if (!v || !br_vlan_should_use(v)) {
888 pr_info("bridge: RTM_NEWNEIGH with unconfigured vlan %d on %s\n", vid, dev->name);
889 return -EINVAL;
890 }
891
892 /* VID was specified, so use it. */
893 err = __br_fdb_add(ndm, br, p, addr, nlh_flags, vid);
894 } else {
895 err = __br_fdb_add(ndm, br, p, addr, nlh_flags, 0);
896 if (err || !vg || !vg->num_vlans)
897 goto out;
898
899 /* We have vlans configured on this port and user didn't
900 * specify a VLAN. To be nice, add/update entry for every
901 * vlan on this port.
902 */
903 list_for_each_entry(v, &vg->vlan_list, vlist) {
904 if (!br_vlan_should_use(v))
905 continue;
906 err = __br_fdb_add(ndm, br, p, addr, nlh_flags, v->vid);
907 if (err)
908 goto out;
909 }
910 }
911
912out:
913 return err;
914}
915
916static int fdb_delete_by_addr_and_port(struct net_bridge *br,
917 const struct net_bridge_port *p,
918 const u8 *addr, u16 vlan)
919{
920 struct net_bridge_fdb_entry *fdb;
921
922 fdb = br_fdb_find(br, addr, vlan);
923 if (!fdb || fdb->dst != p)
924 return -ENOENT;
925
926 fdb_delete(br, fdb);
927
928 return 0;
929}
930
931static int __br_fdb_delete(struct net_bridge *br,
932 const struct net_bridge_port *p,
933 const unsigned char *addr, u16 vid)
934{
935 int err;
936
937 spin_lock_bh(&br->hash_lock);
938 err = fdb_delete_by_addr_and_port(br, p, addr, vid);
939 spin_unlock_bh(&br->hash_lock);
940
941 return err;
942}
943
944/* Remove neighbor entry with RTM_DELNEIGH */
945int br_fdb_delete(struct ndmsg *ndm, struct nlattr *tb[],
946 struct net_device *dev,
947 const unsigned char *addr, u16 vid)
948{
949 struct net_bridge_vlan_group *vg;
950 struct net_bridge_port *p = NULL;
951 struct net_bridge_vlan *v;
952 struct net_bridge *br;
953 int err;
954
955 if (dev->priv_flags & IFF_EBRIDGE) {
956 br = netdev_priv(dev);
957 vg = br_vlan_group(br);
958 } else {
959 p = br_port_get_rtnl(dev);
960 if (!p) {
961 pr_info("bridge: RTM_DELNEIGH %s not a bridge port\n",
962 dev->name);
963 return -EINVAL;
964 }
965 vg = nbp_vlan_group(p);
966 br = p->br;
967 }
968
969 if (vid) {
970 v = br_vlan_find(vg, vid);
971 if (!v) {
972 pr_info("bridge: RTM_DELNEIGH with unconfigured vlan %d on %s\n", vid, dev->name);
973 return -EINVAL;
974 }
975
976 err = __br_fdb_delete(br, p, addr, vid);
977 } else {
978 err = -ENOENT;
979 err &= __br_fdb_delete(br, p, addr, 0);
980 if (!vg || !vg->num_vlans)
981 return err;
982
983 list_for_each_entry(v, &vg->vlan_list, vlist) {
984 if (!br_vlan_should_use(v))
985 continue;
986 err &= __br_fdb_delete(br, p, addr, v->vid);
987 }
988 }
989
990 return err;
991}
992
993int br_fdb_sync_static(struct net_bridge *br, struct net_bridge_port *p)
994{
995 struct net_bridge_fdb_entry *f, *tmp;
996 int err = 0;
997
998 ASSERT_RTNL();
999
1000 /* the key here is that static entries change only under rtnl */
1001 rcu_read_lock();
1002 hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
1003 /* We only care for static entries */
1004 if (!f->is_static)
1005 continue;
1006 err = dev_uc_add(p->dev, f->key.addr.addr);
1007 if (err)
1008 goto rollback;
1009 }
1010done:
1011 rcu_read_unlock();
1012
1013 return err;
1014
1015rollback:
1016 hlist_for_each_entry_rcu(tmp, &br->fdb_list, fdb_node) {
1017 /* We only care for static entries */
1018 if (!tmp->is_static)
1019 continue;
1020 if (tmp == f)
1021 break;
1022 dev_uc_del(p->dev, tmp->key.addr.addr);
1023 }
1024
1025 goto done;
1026}
1027
1028void br_fdb_unsync_static(struct net_bridge *br, struct net_bridge_port *p)
1029{
1030 struct net_bridge_fdb_entry *f;
1031
1032 ASSERT_RTNL();
1033
1034 rcu_read_lock();
1035 hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
1036 /* We only care for static entries */
1037 if (!f->is_static)
1038 continue;
1039
1040 dev_uc_del(p->dev, f->key.addr.addr);
1041 }
1042 rcu_read_unlock();
1043}
1044
1045int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p,
1046 const unsigned char *addr, u16 vid)
1047{
1048 struct net_bridge_fdb_entry *fdb;
1049 bool modified = false;
1050 int err = 0;
1051
1052 trace_br_fdb_external_learn_add(br, p, addr, vid);
1053
1054 spin_lock_bh(&br->hash_lock);
1055
1056 fdb = br_fdb_find(br, addr, vid);
1057 if (!fdb) {
1058 fdb = fdb_create(br, p, addr, vid, 0, 0);
1059 if (!fdb) {
1060 err = -ENOMEM;
1061 goto err_unlock;
1062 }
1063 fdb->added_by_external_learn = 1;
1064 fdb_notify(br, fdb, RTM_NEWNEIGH);
1065 } else {
1066 fdb->updated = jiffies;
1067
1068 if (fdb->dst != p) {
1069 fdb->dst = p;
1070 modified = true;
1071 }
1072
1073 if (fdb->added_by_external_learn) {
1074 /* Refresh entry */
1075 fdb->used = jiffies;
1076 } else if (!fdb->added_by_user) {
1077 /* Take over SW learned entry */
1078 fdb->added_by_external_learn = 1;
1079 modified = true;
1080 }
1081
1082 if (modified)
1083 fdb_notify(br, fdb, RTM_NEWNEIGH);
1084 }
1085
1086err_unlock:
1087 spin_unlock_bh(&br->hash_lock);
1088
1089 return err;
1090}
1091
1092int br_fdb_external_learn_del(struct net_bridge *br, struct net_bridge_port *p,
1093 const unsigned char *addr, u16 vid)
1094{
1095 struct net_bridge_fdb_entry *fdb;
1096 int err = 0;
1097
1098 spin_lock_bh(&br->hash_lock);
1099
1100 fdb = br_fdb_find(br, addr, vid);
1101 if (fdb && fdb->added_by_external_learn)
1102 fdb_delete(br, fdb);
1103 else
1104 err = -ENOENT;
1105
1106 spin_unlock_bh(&br->hash_lock);
1107
1108 return err;
1109}
1110
1111void br_fdb_offloaded_set(struct net_bridge *br, struct net_bridge_port *p,
1112 const unsigned char *addr, u16 vid)
1113{
1114 struct net_bridge_fdb_entry *fdb;
1115
1116 spin_lock_bh(&br->hash_lock);
1117
1118 fdb = br_fdb_find(br, addr, vid);
1119 if (fdb)
1120 fdb->offloaded = 1;
1121
1122 spin_unlock_bh(&br->hash_lock);
1123}
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 fdb_notify(br, f, RTM_DELNEIGH, swdev_notify);
333 call_rcu(&f->rcu, fdb_rcu_free);
334}
335
336/* Delete a local entry if no other port had the same address. */
337static void fdb_delete_local(struct net_bridge *br,
338 const struct net_bridge_port *p,
339 struct net_bridge_fdb_entry *f)
340{
341 const unsigned char *addr = f->key.addr.addr;
342 struct net_bridge_vlan_group *vg;
343 const struct net_bridge_vlan *v;
344 struct net_bridge_port *op;
345 u16 vid = f->key.vlan_id;
346
347 /* Maybe another port has same hw addr? */
348 list_for_each_entry(op, &br->port_list, list) {
349 vg = nbp_vlan_group(op);
350 if (op != p && ether_addr_equal(op->dev->dev_addr, addr) &&
351 (!vid || br_vlan_find(vg, vid))) {
352 f->dst = op;
353 clear_bit(BR_FDB_ADDED_BY_USER, &f->flags);
354 return;
355 }
356 }
357
358 vg = br_vlan_group(br);
359 v = br_vlan_find(vg, vid);
360 /* Maybe bridge device has same hw addr? */
361 if (p && ether_addr_equal(br->dev->dev_addr, addr) &&
362 (!vid || (v && br_vlan_should_use(v)))) {
363 f->dst = NULL;
364 clear_bit(BR_FDB_ADDED_BY_USER, &f->flags);
365 return;
366 }
367
368 fdb_delete(br, f, true);
369}
370
371void br_fdb_find_delete_local(struct net_bridge *br,
372 const struct net_bridge_port *p,
373 const unsigned char *addr, u16 vid)
374{
375 struct net_bridge_fdb_entry *f;
376
377 spin_lock_bh(&br->hash_lock);
378 f = br_fdb_find(br, addr, vid);
379 if (f && test_bit(BR_FDB_LOCAL, &f->flags) &&
380 !test_bit(BR_FDB_ADDED_BY_USER, &f->flags) && f->dst == p)
381 fdb_delete_local(br, p, f);
382 spin_unlock_bh(&br->hash_lock);
383}
384
385static struct net_bridge_fdb_entry *fdb_create(struct net_bridge *br,
386 struct net_bridge_port *source,
387 const unsigned char *addr,
388 __u16 vid,
389 unsigned long flags)
390{
391 struct net_bridge_fdb_entry *fdb;
392 int err;
393
394 fdb = kmem_cache_alloc(br_fdb_cache, GFP_ATOMIC);
395 if (!fdb)
396 return NULL;
397
398 memcpy(fdb->key.addr.addr, addr, ETH_ALEN);
399 WRITE_ONCE(fdb->dst, source);
400 fdb->key.vlan_id = vid;
401 fdb->flags = flags;
402 fdb->updated = fdb->used = jiffies;
403 err = rhashtable_lookup_insert_fast(&br->fdb_hash_tbl, &fdb->rhnode,
404 br_fdb_rht_params);
405 if (err) {
406 kmem_cache_free(br_fdb_cache, fdb);
407 return NULL;
408 }
409
410 hlist_add_head_rcu(&fdb->fdb_node, &br->fdb_list);
411
412 return fdb;
413}
414
415static int fdb_add_local(struct net_bridge *br, struct net_bridge_port *source,
416 const unsigned char *addr, u16 vid)
417{
418 struct net_bridge_fdb_entry *fdb;
419
420 if (!is_valid_ether_addr(addr))
421 return -EINVAL;
422
423 fdb = br_fdb_find(br, addr, vid);
424 if (fdb) {
425 /* it is okay to have multiple ports with same
426 * address, just use the first one.
427 */
428 if (test_bit(BR_FDB_LOCAL, &fdb->flags))
429 return 0;
430 br_warn(br, "adding interface %s with same address as a received packet (addr:%pM, vlan:%u)\n",
431 source ? source->dev->name : br->dev->name, addr, vid);
432 fdb_delete(br, fdb, true);
433 }
434
435 fdb = fdb_create(br, source, addr, vid,
436 BIT(BR_FDB_LOCAL) | BIT(BR_FDB_STATIC));
437 if (!fdb)
438 return -ENOMEM;
439
440 fdb_add_hw_addr(br, addr);
441 fdb_notify(br, fdb, RTM_NEWNEIGH, true);
442 return 0;
443}
444
445void br_fdb_changeaddr(struct net_bridge_port *p, const unsigned char *newaddr)
446{
447 struct net_bridge_vlan_group *vg;
448 struct net_bridge_fdb_entry *f;
449 struct net_bridge *br = p->br;
450 struct net_bridge_vlan *v;
451
452 spin_lock_bh(&br->hash_lock);
453 vg = nbp_vlan_group(p);
454 hlist_for_each_entry(f, &br->fdb_list, fdb_node) {
455 if (f->dst == p && test_bit(BR_FDB_LOCAL, &f->flags) &&
456 !test_bit(BR_FDB_ADDED_BY_USER, &f->flags)) {
457 /* delete old one */
458 fdb_delete_local(br, p, f);
459
460 /* if this port has no vlan information
461 * configured, we can safely be done at
462 * this point.
463 */
464 if (!vg || !vg->num_vlans)
465 goto insert;
466 }
467 }
468
469insert:
470 /* insert new address, may fail if invalid address or dup. */
471 fdb_add_local(br, p, newaddr, 0);
472
473 if (!vg || !vg->num_vlans)
474 goto done;
475
476 /* Now add entries for every VLAN configured on the port.
477 * This function runs under RTNL so the bitmap will not change
478 * from under us.
479 */
480 list_for_each_entry(v, &vg->vlan_list, vlist)
481 fdb_add_local(br, p, newaddr, v->vid);
482
483done:
484 spin_unlock_bh(&br->hash_lock);
485}
486
487void br_fdb_change_mac_address(struct net_bridge *br, const u8 *newaddr)
488{
489 struct net_bridge_vlan_group *vg;
490 struct net_bridge_fdb_entry *f;
491 struct net_bridge_vlan *v;
492
493 spin_lock_bh(&br->hash_lock);
494
495 /* If old entry was unassociated with any port, then delete it. */
496 f = br_fdb_find(br, br->dev->dev_addr, 0);
497 if (f && test_bit(BR_FDB_LOCAL, &f->flags) &&
498 !f->dst && !test_bit(BR_FDB_ADDED_BY_USER, &f->flags))
499 fdb_delete_local(br, NULL, f);
500
501 fdb_add_local(br, NULL, newaddr, 0);
502 vg = br_vlan_group(br);
503 if (!vg || !vg->num_vlans)
504 goto out;
505 /* Now remove and add entries for every VLAN configured on the
506 * bridge. This function runs under RTNL so the bitmap will not
507 * change from under us.
508 */
509 list_for_each_entry(v, &vg->vlan_list, vlist) {
510 if (!br_vlan_should_use(v))
511 continue;
512 f = br_fdb_find(br, br->dev->dev_addr, v->vid);
513 if (f && test_bit(BR_FDB_LOCAL, &f->flags) &&
514 !f->dst && !test_bit(BR_FDB_ADDED_BY_USER, &f->flags))
515 fdb_delete_local(br, NULL, f);
516 fdb_add_local(br, NULL, newaddr, v->vid);
517 }
518out:
519 spin_unlock_bh(&br->hash_lock);
520}
521
522void br_fdb_cleanup(struct work_struct *work)
523{
524 struct net_bridge *br = container_of(work, struct net_bridge,
525 gc_work.work);
526 struct net_bridge_fdb_entry *f = NULL;
527 unsigned long delay = hold_time(br);
528 unsigned long work_delay = delay;
529 unsigned long now = jiffies;
530
531 /* this part is tricky, in order to avoid blocking learning and
532 * consequently forwarding, we rely on rcu to delete objects with
533 * delayed freeing allowing us to continue traversing
534 */
535 rcu_read_lock();
536 hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
537 unsigned long this_timer = f->updated + delay;
538
539 if (test_bit(BR_FDB_STATIC, &f->flags) ||
540 test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &f->flags)) {
541 if (test_bit(BR_FDB_NOTIFY, &f->flags)) {
542 if (time_after(this_timer, now))
543 work_delay = min(work_delay,
544 this_timer - now);
545 else if (!test_and_set_bit(BR_FDB_NOTIFY_INACTIVE,
546 &f->flags))
547 fdb_notify(br, f, RTM_NEWNEIGH, false);
548 }
549 continue;
550 }
551
552 if (time_after(this_timer, now)) {
553 work_delay = min(work_delay, this_timer - now);
554 } else {
555 spin_lock_bh(&br->hash_lock);
556 if (!hlist_unhashed(&f->fdb_node))
557 fdb_delete(br, f, true);
558 spin_unlock_bh(&br->hash_lock);
559 }
560 }
561 rcu_read_unlock();
562
563 /* Cleanup minimum 10 milliseconds apart */
564 work_delay = max_t(unsigned long, work_delay, msecs_to_jiffies(10));
565 mod_delayed_work(system_long_wq, &br->gc_work, work_delay);
566}
567
568static bool __fdb_flush_matches(const struct net_bridge *br,
569 const struct net_bridge_fdb_entry *f,
570 const struct net_bridge_fdb_flush_desc *desc)
571{
572 const struct net_bridge_port *dst = READ_ONCE(f->dst);
573 int port_ifidx = dst ? dst->dev->ifindex : br->dev->ifindex;
574
575 if (desc->vlan_id && desc->vlan_id != f->key.vlan_id)
576 return false;
577 if (desc->port_ifindex && desc->port_ifindex != port_ifidx)
578 return false;
579 if (desc->flags_mask && (f->flags & desc->flags_mask) != desc->flags)
580 return false;
581
582 return true;
583}
584
585/* Flush forwarding database entries matching the description */
586void br_fdb_flush(struct net_bridge *br,
587 const struct net_bridge_fdb_flush_desc *desc)
588{
589 struct net_bridge_fdb_entry *f;
590
591 rcu_read_lock();
592 hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
593 if (!__fdb_flush_matches(br, f, desc))
594 continue;
595
596 spin_lock_bh(&br->hash_lock);
597 if (!hlist_unhashed(&f->fdb_node))
598 fdb_delete(br, f, true);
599 spin_unlock_bh(&br->hash_lock);
600 }
601 rcu_read_unlock();
602}
603
604static unsigned long __ndm_state_to_fdb_flags(u16 ndm_state)
605{
606 unsigned long flags = 0;
607
608 if (ndm_state & NUD_PERMANENT)
609 __set_bit(BR_FDB_LOCAL, &flags);
610 if (ndm_state & NUD_NOARP)
611 __set_bit(BR_FDB_STATIC, &flags);
612
613 return flags;
614}
615
616static unsigned long __ndm_flags_to_fdb_flags(u8 ndm_flags)
617{
618 unsigned long flags = 0;
619
620 if (ndm_flags & NTF_USE)
621 __set_bit(BR_FDB_ADDED_BY_USER, &flags);
622 if (ndm_flags & NTF_EXT_LEARNED)
623 __set_bit(BR_FDB_ADDED_BY_EXT_LEARN, &flags);
624 if (ndm_flags & NTF_OFFLOADED)
625 __set_bit(BR_FDB_OFFLOADED, &flags);
626 if (ndm_flags & NTF_STICKY)
627 __set_bit(BR_FDB_STICKY, &flags);
628
629 return flags;
630}
631
632static int __fdb_flush_validate_ifindex(const struct net_bridge *br,
633 int ifindex,
634 struct netlink_ext_ack *extack)
635{
636 const struct net_device *dev;
637
638 dev = __dev_get_by_index(dev_net(br->dev), ifindex);
639 if (!dev) {
640 NL_SET_ERR_MSG_MOD(extack, "Unknown flush device ifindex");
641 return -ENODEV;
642 }
643 if (!netif_is_bridge_master(dev) && !netif_is_bridge_port(dev)) {
644 NL_SET_ERR_MSG_MOD(extack, "Flush device is not a bridge or bridge port");
645 return -EINVAL;
646 }
647 if (netif_is_bridge_master(dev) && dev != br->dev) {
648 NL_SET_ERR_MSG_MOD(extack,
649 "Flush bridge device does not match target bridge device");
650 return -EINVAL;
651 }
652 if (netif_is_bridge_port(dev)) {
653 struct net_bridge_port *p = br_port_get_rtnl(dev);
654
655 if (p->br != br) {
656 NL_SET_ERR_MSG_MOD(extack, "Port belongs to a different bridge device");
657 return -EINVAL;
658 }
659 }
660
661 return 0;
662}
663
664int br_fdb_delete_bulk(struct ndmsg *ndm, struct nlattr *tb[],
665 struct net_device *dev, u16 vid,
666 struct netlink_ext_ack *extack)
667{
668 u8 ndm_flags = ndm->ndm_flags & ~FDB_FLUSH_IGNORED_NDM_FLAGS;
669 struct net_bridge_fdb_flush_desc desc = { .vlan_id = vid };
670 struct net_bridge_port *p = NULL;
671 struct net_bridge *br;
672
673 if (netif_is_bridge_master(dev)) {
674 br = netdev_priv(dev);
675 } else {
676 p = br_port_get_rtnl(dev);
677 if (!p) {
678 NL_SET_ERR_MSG_MOD(extack, "Device is not a bridge port");
679 return -EINVAL;
680 }
681 br = p->br;
682 }
683
684 if (ndm_flags & ~FDB_FLUSH_ALLOWED_NDM_FLAGS) {
685 NL_SET_ERR_MSG(extack, "Unsupported fdb flush ndm flag bits set");
686 return -EINVAL;
687 }
688 if (ndm->ndm_state & ~FDB_FLUSH_ALLOWED_NDM_STATES) {
689 NL_SET_ERR_MSG(extack, "Unsupported fdb flush ndm state bits set");
690 return -EINVAL;
691 }
692
693 desc.flags |= __ndm_state_to_fdb_flags(ndm->ndm_state);
694 desc.flags |= __ndm_flags_to_fdb_flags(ndm_flags);
695 if (tb[NDA_NDM_STATE_MASK]) {
696 u16 ndm_state_mask = nla_get_u16(tb[NDA_NDM_STATE_MASK]);
697
698 desc.flags_mask |= __ndm_state_to_fdb_flags(ndm_state_mask);
699 }
700 if (tb[NDA_NDM_FLAGS_MASK]) {
701 u8 ndm_flags_mask = nla_get_u8(tb[NDA_NDM_FLAGS_MASK]);
702
703 desc.flags_mask |= __ndm_flags_to_fdb_flags(ndm_flags_mask);
704 }
705 if (tb[NDA_IFINDEX]) {
706 int err, ifidx = nla_get_s32(tb[NDA_IFINDEX]);
707
708 err = __fdb_flush_validate_ifindex(br, ifidx, extack);
709 if (err)
710 return err;
711 desc.port_ifindex = ifidx;
712 } else if (p) {
713 /* flush was invoked with port device and NTF_MASTER */
714 desc.port_ifindex = p->dev->ifindex;
715 }
716
717 br_debug(br, "flushing port ifindex: %d vlan id: %u flags: 0x%lx flags mask: 0x%lx\n",
718 desc.port_ifindex, desc.vlan_id, desc.flags, desc.flags_mask);
719
720 br_fdb_flush(br, &desc);
721
722 return 0;
723}
724
725/* Flush all entries referring to a specific port.
726 * if do_all is set also flush static entries
727 * if vid is set delete all entries that match the vlan_id
728 */
729void br_fdb_delete_by_port(struct net_bridge *br,
730 const struct net_bridge_port *p,
731 u16 vid,
732 int do_all)
733{
734 struct net_bridge_fdb_entry *f;
735 struct hlist_node *tmp;
736
737 spin_lock_bh(&br->hash_lock);
738 hlist_for_each_entry_safe(f, tmp, &br->fdb_list, fdb_node) {
739 if (f->dst != p)
740 continue;
741
742 if (!do_all)
743 if (test_bit(BR_FDB_STATIC, &f->flags) ||
744 (test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &f->flags) &&
745 !test_bit(BR_FDB_OFFLOADED, &f->flags)) ||
746 (vid && f->key.vlan_id != vid))
747 continue;
748
749 if (test_bit(BR_FDB_LOCAL, &f->flags))
750 fdb_delete_local(br, p, f);
751 else
752 fdb_delete(br, f, true);
753 }
754 spin_unlock_bh(&br->hash_lock);
755}
756
757#if IS_ENABLED(CONFIG_ATM_LANE)
758/* Interface used by ATM LANE hook to test
759 * if an addr is on some other bridge port */
760int br_fdb_test_addr(struct net_device *dev, unsigned char *addr)
761{
762 struct net_bridge_fdb_entry *fdb;
763 struct net_bridge_port *port;
764 int ret;
765
766 rcu_read_lock();
767 port = br_port_get_rcu(dev);
768 if (!port)
769 ret = 0;
770 else {
771 const struct net_bridge_port *dst = NULL;
772
773 fdb = br_fdb_find_rcu(port->br, addr, 0);
774 if (fdb)
775 dst = READ_ONCE(fdb->dst);
776
777 ret = dst && dst->dev != dev &&
778 dst->state == BR_STATE_FORWARDING;
779 }
780 rcu_read_unlock();
781
782 return ret;
783}
784#endif /* CONFIG_ATM_LANE */
785
786/*
787 * Fill buffer with forwarding table records in
788 * the API format.
789 */
790int br_fdb_fillbuf(struct net_bridge *br, void *buf,
791 unsigned long maxnum, unsigned long skip)
792{
793 struct net_bridge_fdb_entry *f;
794 struct __fdb_entry *fe = buf;
795 int num = 0;
796
797 memset(buf, 0, maxnum*sizeof(struct __fdb_entry));
798
799 rcu_read_lock();
800 hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
801 if (num >= maxnum)
802 break;
803
804 if (has_expired(br, f))
805 continue;
806
807 /* ignore pseudo entry for local MAC address */
808 if (!f->dst)
809 continue;
810
811 if (skip) {
812 --skip;
813 continue;
814 }
815
816 /* convert from internal format to API */
817 memcpy(fe->mac_addr, f->key.addr.addr, ETH_ALEN);
818
819 /* due to ABI compat need to split into hi/lo */
820 fe->port_no = f->dst->port_no;
821 fe->port_hi = f->dst->port_no >> 8;
822
823 fe->is_local = test_bit(BR_FDB_LOCAL, &f->flags);
824 if (!test_bit(BR_FDB_STATIC, &f->flags))
825 fe->ageing_timer_value = jiffies_delta_to_clock_t(jiffies - f->updated);
826 ++fe;
827 ++num;
828 }
829 rcu_read_unlock();
830
831 return num;
832}
833
834/* Add entry for local address of interface */
835int br_fdb_add_local(struct net_bridge *br, struct net_bridge_port *source,
836 const unsigned char *addr, u16 vid)
837{
838 int ret;
839
840 spin_lock_bh(&br->hash_lock);
841 ret = fdb_add_local(br, source, addr, vid);
842 spin_unlock_bh(&br->hash_lock);
843 return ret;
844}
845
846/* returns true if the fdb was modified */
847static bool __fdb_mark_active(struct net_bridge_fdb_entry *fdb)
848{
849 return !!(test_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags) &&
850 test_and_clear_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags));
851}
852
853void br_fdb_update(struct net_bridge *br, struct net_bridge_port *source,
854 const unsigned char *addr, u16 vid, unsigned long flags)
855{
856 struct net_bridge_fdb_entry *fdb;
857
858 /* some users want to always flood. */
859 if (hold_time(br) == 0)
860 return;
861
862 fdb = fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
863 if (likely(fdb)) {
864 /* attempt to update an entry for a local interface */
865 if (unlikely(test_bit(BR_FDB_LOCAL, &fdb->flags))) {
866 if (net_ratelimit())
867 br_warn(br, "received packet on %s with own address as source address (addr:%pM, vlan:%u)\n",
868 source->dev->name, addr, vid);
869 } else {
870 unsigned long now = jiffies;
871 bool fdb_modified = false;
872
873 if (now != fdb->updated) {
874 fdb->updated = now;
875 fdb_modified = __fdb_mark_active(fdb);
876 }
877
878 /* fastpath: update of existing entry */
879 if (unlikely(source != READ_ONCE(fdb->dst) &&
880 !test_bit(BR_FDB_STICKY, &fdb->flags))) {
881 br_switchdev_fdb_notify(br, fdb, RTM_DELNEIGH);
882 WRITE_ONCE(fdb->dst, source);
883 fdb_modified = true;
884 /* Take over HW learned entry */
885 if (unlikely(test_bit(BR_FDB_ADDED_BY_EXT_LEARN,
886 &fdb->flags)))
887 clear_bit(BR_FDB_ADDED_BY_EXT_LEARN,
888 &fdb->flags);
889 /* Clear locked flag when roaming to an
890 * unlocked port.
891 */
892 if (unlikely(test_bit(BR_FDB_LOCKED, &fdb->flags)))
893 clear_bit(BR_FDB_LOCKED, &fdb->flags);
894 }
895
896 if (unlikely(test_bit(BR_FDB_ADDED_BY_USER, &flags)))
897 set_bit(BR_FDB_ADDED_BY_USER, &fdb->flags);
898 if (unlikely(fdb_modified)) {
899 trace_br_fdb_update(br, source, addr, vid, flags);
900 fdb_notify(br, fdb, RTM_NEWNEIGH, true);
901 }
902 }
903 } else {
904 spin_lock(&br->hash_lock);
905 fdb = fdb_create(br, source, addr, vid, flags);
906 if (fdb) {
907 trace_br_fdb_update(br, source, addr, vid, flags);
908 fdb_notify(br, fdb, RTM_NEWNEIGH, true);
909 }
910 /* else we lose race and someone else inserts
911 * it first, don't bother updating
912 */
913 spin_unlock(&br->hash_lock);
914 }
915}
916
917/* Dump information about entries, in response to GETNEIGH */
918int br_fdb_dump(struct sk_buff *skb,
919 struct netlink_callback *cb,
920 struct net_device *dev,
921 struct net_device *filter_dev,
922 int *idx)
923{
924 struct net_bridge *br = netdev_priv(dev);
925 struct net_bridge_fdb_entry *f;
926 int err = 0;
927
928 if (!netif_is_bridge_master(dev))
929 return err;
930
931 if (!filter_dev) {
932 err = ndo_dflt_fdb_dump(skb, cb, dev, NULL, idx);
933 if (err < 0)
934 return err;
935 }
936
937 rcu_read_lock();
938 hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
939 if (*idx < cb->args[2])
940 goto skip;
941 if (filter_dev && (!f->dst || f->dst->dev != filter_dev)) {
942 if (filter_dev != dev)
943 goto skip;
944 /* !f->dst is a special case for bridge
945 * It means the MAC belongs to the bridge
946 * Therefore need a little more filtering
947 * we only want to dump the !f->dst case
948 */
949 if (f->dst)
950 goto skip;
951 }
952 if (!filter_dev && f->dst)
953 goto skip;
954
955 err = fdb_fill_info(skb, br, f,
956 NETLINK_CB(cb->skb).portid,
957 cb->nlh->nlmsg_seq,
958 RTM_NEWNEIGH,
959 NLM_F_MULTI);
960 if (err < 0)
961 break;
962skip:
963 *idx += 1;
964 }
965 rcu_read_unlock();
966
967 return err;
968}
969
970int br_fdb_get(struct sk_buff *skb,
971 struct nlattr *tb[],
972 struct net_device *dev,
973 const unsigned char *addr,
974 u16 vid, u32 portid, u32 seq,
975 struct netlink_ext_ack *extack)
976{
977 struct net_bridge *br = netdev_priv(dev);
978 struct net_bridge_fdb_entry *f;
979 int err = 0;
980
981 rcu_read_lock();
982 f = br_fdb_find_rcu(br, addr, vid);
983 if (!f) {
984 NL_SET_ERR_MSG(extack, "Fdb entry not found");
985 err = -ENOENT;
986 goto errout;
987 }
988
989 err = fdb_fill_info(skb, br, f, portid, seq,
990 RTM_NEWNEIGH, 0);
991errout:
992 rcu_read_unlock();
993 return err;
994}
995
996/* returns true if the fdb is modified */
997static bool fdb_handle_notify(struct net_bridge_fdb_entry *fdb, u8 notify)
998{
999 bool modified = false;
1000
1001 /* allow to mark an entry as inactive, usually done on creation */
1002 if ((notify & FDB_NOTIFY_INACTIVE_BIT) &&
1003 !test_and_set_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags))
1004 modified = true;
1005
1006 if ((notify & FDB_NOTIFY_BIT) &&
1007 !test_and_set_bit(BR_FDB_NOTIFY, &fdb->flags)) {
1008 /* enabled activity tracking */
1009 modified = true;
1010 } else if (!(notify & FDB_NOTIFY_BIT) &&
1011 test_and_clear_bit(BR_FDB_NOTIFY, &fdb->flags)) {
1012 /* disabled activity tracking, clear notify state */
1013 clear_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags);
1014 modified = true;
1015 }
1016
1017 return modified;
1018}
1019
1020/* Update (create or replace) forwarding database entry */
1021static int fdb_add_entry(struct net_bridge *br, struct net_bridge_port *source,
1022 const u8 *addr, struct ndmsg *ndm, u16 flags, u16 vid,
1023 struct nlattr *nfea_tb[])
1024{
1025 bool is_sticky = !!(ndm->ndm_flags & NTF_STICKY);
1026 bool refresh = !nfea_tb[NFEA_DONT_REFRESH];
1027 struct net_bridge_fdb_entry *fdb;
1028 u16 state = ndm->ndm_state;
1029 bool modified = false;
1030 u8 notify = 0;
1031
1032 /* If the port cannot learn allow only local and static entries */
1033 if (source && !(state & NUD_PERMANENT) && !(state & NUD_NOARP) &&
1034 !(source->state == BR_STATE_LEARNING ||
1035 source->state == BR_STATE_FORWARDING))
1036 return -EPERM;
1037
1038 if (!source && !(state & NUD_PERMANENT)) {
1039 pr_info("bridge: RTM_NEWNEIGH %s without NUD_PERMANENT\n",
1040 br->dev->name);
1041 return -EINVAL;
1042 }
1043
1044 if (is_sticky && (state & NUD_PERMANENT))
1045 return -EINVAL;
1046
1047 if (nfea_tb[NFEA_ACTIVITY_NOTIFY]) {
1048 notify = nla_get_u8(nfea_tb[NFEA_ACTIVITY_NOTIFY]);
1049 if ((notify & ~BR_FDB_NOTIFY_SETTABLE_BITS) ||
1050 (notify & BR_FDB_NOTIFY_SETTABLE_BITS) == FDB_NOTIFY_INACTIVE_BIT)
1051 return -EINVAL;
1052 }
1053
1054 fdb = br_fdb_find(br, addr, vid);
1055 if (fdb == NULL) {
1056 if (!(flags & NLM_F_CREATE))
1057 return -ENOENT;
1058
1059 fdb = fdb_create(br, source, addr, vid, 0);
1060 if (!fdb)
1061 return -ENOMEM;
1062
1063 modified = true;
1064 } else {
1065 if (flags & NLM_F_EXCL)
1066 return -EEXIST;
1067
1068 if (READ_ONCE(fdb->dst) != source) {
1069 WRITE_ONCE(fdb->dst, source);
1070 modified = true;
1071 }
1072 }
1073
1074 if (fdb_to_nud(br, fdb) != state) {
1075 if (state & NUD_PERMANENT) {
1076 set_bit(BR_FDB_LOCAL, &fdb->flags);
1077 if (!test_and_set_bit(BR_FDB_STATIC, &fdb->flags))
1078 fdb_add_hw_addr(br, addr);
1079 } else if (state & NUD_NOARP) {
1080 clear_bit(BR_FDB_LOCAL, &fdb->flags);
1081 if (!test_and_set_bit(BR_FDB_STATIC, &fdb->flags))
1082 fdb_add_hw_addr(br, addr);
1083 } else {
1084 clear_bit(BR_FDB_LOCAL, &fdb->flags);
1085 if (test_and_clear_bit(BR_FDB_STATIC, &fdb->flags))
1086 fdb_del_hw_addr(br, addr);
1087 }
1088
1089 modified = true;
1090 }
1091
1092 if (is_sticky != test_bit(BR_FDB_STICKY, &fdb->flags)) {
1093 change_bit(BR_FDB_STICKY, &fdb->flags);
1094 modified = true;
1095 }
1096
1097 if (test_and_clear_bit(BR_FDB_LOCKED, &fdb->flags))
1098 modified = true;
1099
1100 if (fdb_handle_notify(fdb, notify))
1101 modified = true;
1102
1103 set_bit(BR_FDB_ADDED_BY_USER, &fdb->flags);
1104
1105 fdb->used = jiffies;
1106 if (modified) {
1107 if (refresh)
1108 fdb->updated = jiffies;
1109 fdb_notify(br, fdb, RTM_NEWNEIGH, true);
1110 }
1111
1112 return 0;
1113}
1114
1115static int __br_fdb_add(struct ndmsg *ndm, struct net_bridge *br,
1116 struct net_bridge_port *p, const unsigned char *addr,
1117 u16 nlh_flags, u16 vid, struct nlattr *nfea_tb[],
1118 struct netlink_ext_ack *extack)
1119{
1120 int err = 0;
1121
1122 if (ndm->ndm_flags & NTF_USE) {
1123 if (!p) {
1124 pr_info("bridge: RTM_NEWNEIGH %s with NTF_USE is not supported\n",
1125 br->dev->name);
1126 return -EINVAL;
1127 }
1128 if (!nbp_state_should_learn(p))
1129 return 0;
1130
1131 local_bh_disable();
1132 rcu_read_lock();
1133 br_fdb_update(br, p, addr, vid, BIT(BR_FDB_ADDED_BY_USER));
1134 rcu_read_unlock();
1135 local_bh_enable();
1136 } else if (ndm->ndm_flags & NTF_EXT_LEARNED) {
1137 if (!p && !(ndm->ndm_state & NUD_PERMANENT)) {
1138 NL_SET_ERR_MSG_MOD(extack,
1139 "FDB entry towards bridge must be permanent");
1140 return -EINVAL;
1141 }
1142 err = br_fdb_external_learn_add(br, p, addr, vid, false, true);
1143 } else {
1144 spin_lock_bh(&br->hash_lock);
1145 err = fdb_add_entry(br, p, addr, ndm, nlh_flags, vid, nfea_tb);
1146 spin_unlock_bh(&br->hash_lock);
1147 }
1148
1149 return err;
1150}
1151
1152static const struct nla_policy br_nda_fdb_pol[NFEA_MAX + 1] = {
1153 [NFEA_ACTIVITY_NOTIFY] = { .type = NLA_U8 },
1154 [NFEA_DONT_REFRESH] = { .type = NLA_FLAG },
1155};
1156
1157/* Add new permanent fdb entry with RTM_NEWNEIGH */
1158int br_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
1159 struct net_device *dev,
1160 const unsigned char *addr, u16 vid, u16 nlh_flags,
1161 struct netlink_ext_ack *extack)
1162{
1163 struct nlattr *nfea_tb[NFEA_MAX + 1], *attr;
1164 struct net_bridge_vlan_group *vg;
1165 struct net_bridge_port *p = NULL;
1166 struct net_bridge_vlan *v;
1167 struct net_bridge *br = NULL;
1168 u32 ext_flags = 0;
1169 int err = 0;
1170
1171 trace_br_fdb_add(ndm, dev, addr, vid, nlh_flags);
1172
1173 if (!(ndm->ndm_state & (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE))) {
1174 pr_info("bridge: RTM_NEWNEIGH with invalid state %#x\n", ndm->ndm_state);
1175 return -EINVAL;
1176 }
1177
1178 if (is_zero_ether_addr(addr)) {
1179 pr_info("bridge: RTM_NEWNEIGH with invalid ether address\n");
1180 return -EINVAL;
1181 }
1182
1183 if (netif_is_bridge_master(dev)) {
1184 br = netdev_priv(dev);
1185 vg = br_vlan_group(br);
1186 } else {
1187 p = br_port_get_rtnl(dev);
1188 if (!p) {
1189 pr_info("bridge: RTM_NEWNEIGH %s not a bridge port\n",
1190 dev->name);
1191 return -EINVAL;
1192 }
1193 br = p->br;
1194 vg = nbp_vlan_group(p);
1195 }
1196
1197 if (tb[NDA_FLAGS_EXT])
1198 ext_flags = nla_get_u32(tb[NDA_FLAGS_EXT]);
1199
1200 if (ext_flags & NTF_EXT_LOCKED) {
1201 NL_SET_ERR_MSG_MOD(extack, "Cannot add FDB entry with \"locked\" flag set");
1202 return -EINVAL;
1203 }
1204
1205 if (tb[NDA_FDB_EXT_ATTRS]) {
1206 attr = tb[NDA_FDB_EXT_ATTRS];
1207 err = nla_parse_nested(nfea_tb, NFEA_MAX, attr,
1208 br_nda_fdb_pol, extack);
1209 if (err)
1210 return err;
1211 } else {
1212 memset(nfea_tb, 0, sizeof(struct nlattr *) * (NFEA_MAX + 1));
1213 }
1214
1215 if (vid) {
1216 v = br_vlan_find(vg, vid);
1217 if (!v || !br_vlan_should_use(v)) {
1218 pr_info("bridge: RTM_NEWNEIGH with unconfigured vlan %d on %s\n", vid, dev->name);
1219 return -EINVAL;
1220 }
1221
1222 /* VID was specified, so use it. */
1223 err = __br_fdb_add(ndm, br, p, addr, nlh_flags, vid, nfea_tb,
1224 extack);
1225 } else {
1226 err = __br_fdb_add(ndm, br, p, addr, nlh_flags, 0, nfea_tb,
1227 extack);
1228 if (err || !vg || !vg->num_vlans)
1229 goto out;
1230
1231 /* We have vlans configured on this port and user didn't
1232 * specify a VLAN. To be nice, add/update entry for every
1233 * vlan on this port.
1234 */
1235 list_for_each_entry(v, &vg->vlan_list, vlist) {
1236 if (!br_vlan_should_use(v))
1237 continue;
1238 err = __br_fdb_add(ndm, br, p, addr, nlh_flags, v->vid,
1239 nfea_tb, extack);
1240 if (err)
1241 goto out;
1242 }
1243 }
1244
1245out:
1246 return err;
1247}
1248
1249static int fdb_delete_by_addr_and_port(struct net_bridge *br,
1250 const struct net_bridge_port *p,
1251 const u8 *addr, u16 vlan)
1252{
1253 struct net_bridge_fdb_entry *fdb;
1254
1255 fdb = br_fdb_find(br, addr, vlan);
1256 if (!fdb || READ_ONCE(fdb->dst) != p)
1257 return -ENOENT;
1258
1259 fdb_delete(br, fdb, true);
1260
1261 return 0;
1262}
1263
1264static int __br_fdb_delete(struct net_bridge *br,
1265 const struct net_bridge_port *p,
1266 const unsigned char *addr, u16 vid)
1267{
1268 int err;
1269
1270 spin_lock_bh(&br->hash_lock);
1271 err = fdb_delete_by_addr_and_port(br, p, addr, vid);
1272 spin_unlock_bh(&br->hash_lock);
1273
1274 return err;
1275}
1276
1277/* Remove neighbor entry with RTM_DELNEIGH */
1278int br_fdb_delete(struct ndmsg *ndm, struct nlattr *tb[],
1279 struct net_device *dev,
1280 const unsigned char *addr, u16 vid,
1281 struct netlink_ext_ack *extack)
1282{
1283 struct net_bridge_vlan_group *vg;
1284 struct net_bridge_port *p = NULL;
1285 struct net_bridge_vlan *v;
1286 struct net_bridge *br;
1287 int err;
1288
1289 if (netif_is_bridge_master(dev)) {
1290 br = netdev_priv(dev);
1291 vg = br_vlan_group(br);
1292 } else {
1293 p = br_port_get_rtnl(dev);
1294 if (!p) {
1295 pr_info("bridge: RTM_DELNEIGH %s not a bridge port\n",
1296 dev->name);
1297 return -EINVAL;
1298 }
1299 vg = nbp_vlan_group(p);
1300 br = p->br;
1301 }
1302
1303 if (vid) {
1304 v = br_vlan_find(vg, vid);
1305 if (!v) {
1306 pr_info("bridge: RTM_DELNEIGH with unconfigured vlan %d on %s\n", vid, dev->name);
1307 return -EINVAL;
1308 }
1309
1310 err = __br_fdb_delete(br, p, addr, vid);
1311 } else {
1312 err = -ENOENT;
1313 err &= __br_fdb_delete(br, p, addr, 0);
1314 if (!vg || !vg->num_vlans)
1315 return err;
1316
1317 list_for_each_entry(v, &vg->vlan_list, vlist) {
1318 if (!br_vlan_should_use(v))
1319 continue;
1320 err &= __br_fdb_delete(br, p, addr, v->vid);
1321 }
1322 }
1323
1324 return err;
1325}
1326
1327int br_fdb_sync_static(struct net_bridge *br, struct net_bridge_port *p)
1328{
1329 struct net_bridge_fdb_entry *f, *tmp;
1330 int err = 0;
1331
1332 ASSERT_RTNL();
1333
1334 /* the key here is that static entries change only under rtnl */
1335 rcu_read_lock();
1336 hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
1337 /* We only care for static entries */
1338 if (!test_bit(BR_FDB_STATIC, &f->flags))
1339 continue;
1340 err = dev_uc_add(p->dev, f->key.addr.addr);
1341 if (err)
1342 goto rollback;
1343 }
1344done:
1345 rcu_read_unlock();
1346
1347 return err;
1348
1349rollback:
1350 hlist_for_each_entry_rcu(tmp, &br->fdb_list, fdb_node) {
1351 /* We only care for static entries */
1352 if (!test_bit(BR_FDB_STATIC, &tmp->flags))
1353 continue;
1354 if (tmp == f)
1355 break;
1356 dev_uc_del(p->dev, tmp->key.addr.addr);
1357 }
1358
1359 goto done;
1360}
1361
1362void br_fdb_unsync_static(struct net_bridge *br, struct net_bridge_port *p)
1363{
1364 struct net_bridge_fdb_entry *f;
1365
1366 ASSERT_RTNL();
1367
1368 rcu_read_lock();
1369 hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
1370 /* We only care for static entries */
1371 if (!test_bit(BR_FDB_STATIC, &f->flags))
1372 continue;
1373
1374 dev_uc_del(p->dev, f->key.addr.addr);
1375 }
1376 rcu_read_unlock();
1377}
1378
1379int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p,
1380 const unsigned char *addr, u16 vid, bool locked,
1381 bool swdev_notify)
1382{
1383 struct net_bridge_fdb_entry *fdb;
1384 bool modified = false;
1385 int err = 0;
1386
1387 trace_br_fdb_external_learn_add(br, p, addr, vid);
1388
1389 if (locked && (!p || !(p->flags & BR_PORT_MAB)))
1390 return -EINVAL;
1391
1392 spin_lock_bh(&br->hash_lock);
1393
1394 fdb = br_fdb_find(br, addr, vid);
1395 if (!fdb) {
1396 unsigned long flags = BIT(BR_FDB_ADDED_BY_EXT_LEARN);
1397
1398 if (swdev_notify)
1399 flags |= BIT(BR_FDB_ADDED_BY_USER);
1400
1401 if (!p)
1402 flags |= BIT(BR_FDB_LOCAL);
1403
1404 if (locked)
1405 flags |= BIT(BR_FDB_LOCKED);
1406
1407 fdb = fdb_create(br, p, addr, vid, flags);
1408 if (!fdb) {
1409 err = -ENOMEM;
1410 goto err_unlock;
1411 }
1412 fdb_notify(br, fdb, RTM_NEWNEIGH, swdev_notify);
1413 } else {
1414 if (locked &&
1415 (!test_bit(BR_FDB_LOCKED, &fdb->flags) ||
1416 READ_ONCE(fdb->dst) != p)) {
1417 err = -EINVAL;
1418 goto err_unlock;
1419 }
1420
1421 fdb->updated = jiffies;
1422
1423 if (READ_ONCE(fdb->dst) != p) {
1424 WRITE_ONCE(fdb->dst, p);
1425 modified = true;
1426 }
1427
1428 if (test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags)) {
1429 /* Refresh entry */
1430 fdb->used = jiffies;
1431 } else if (!test_bit(BR_FDB_ADDED_BY_USER, &fdb->flags)) {
1432 /* Take over SW learned entry */
1433 set_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags);
1434 modified = true;
1435 }
1436
1437 if (locked != test_bit(BR_FDB_LOCKED, &fdb->flags)) {
1438 change_bit(BR_FDB_LOCKED, &fdb->flags);
1439 modified = true;
1440 }
1441
1442 if (swdev_notify)
1443 set_bit(BR_FDB_ADDED_BY_USER, &fdb->flags);
1444
1445 if (!p)
1446 set_bit(BR_FDB_LOCAL, &fdb->flags);
1447
1448 if (modified)
1449 fdb_notify(br, fdb, RTM_NEWNEIGH, swdev_notify);
1450 }
1451
1452err_unlock:
1453 spin_unlock_bh(&br->hash_lock);
1454
1455 return err;
1456}
1457
1458int br_fdb_external_learn_del(struct net_bridge *br, struct net_bridge_port *p,
1459 const unsigned char *addr, u16 vid,
1460 bool swdev_notify)
1461{
1462 struct net_bridge_fdb_entry *fdb;
1463 int err = 0;
1464
1465 spin_lock_bh(&br->hash_lock);
1466
1467 fdb = br_fdb_find(br, addr, vid);
1468 if (fdb && test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags))
1469 fdb_delete(br, fdb, swdev_notify);
1470 else
1471 err = -ENOENT;
1472
1473 spin_unlock_bh(&br->hash_lock);
1474
1475 return err;
1476}
1477
1478void br_fdb_offloaded_set(struct net_bridge *br, struct net_bridge_port *p,
1479 const unsigned char *addr, u16 vid, bool offloaded)
1480{
1481 struct net_bridge_fdb_entry *fdb;
1482
1483 spin_lock_bh(&br->hash_lock);
1484
1485 fdb = br_fdb_find(br, addr, vid);
1486 if (fdb && offloaded != test_bit(BR_FDB_OFFLOADED, &fdb->flags))
1487 change_bit(BR_FDB_OFFLOADED, &fdb->flags);
1488
1489 spin_unlock_bh(&br->hash_lock);
1490}
1491
1492void br_fdb_clear_offload(const struct net_device *dev, u16 vid)
1493{
1494 struct net_bridge_fdb_entry *f;
1495 struct net_bridge_port *p;
1496
1497 ASSERT_RTNL();
1498
1499 p = br_port_get_rtnl(dev);
1500 if (!p)
1501 return;
1502
1503 spin_lock_bh(&p->br->hash_lock);
1504 hlist_for_each_entry(f, &p->br->fdb_list, fdb_node) {
1505 if (f->dst == p && f->key.vlan_id == vid)
1506 clear_bit(BR_FDB_OFFLOADED, &f->flags);
1507 }
1508 spin_unlock_bh(&p->br->hash_lock);
1509}
1510EXPORT_SYMBOL_GPL(br_fdb_clear_offload);