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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 "br_private.h"
27
28static struct kmem_cache *br_fdb_cache __read_mostly;
29static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
30 const unsigned char *addr);
31static void fdb_notify(const struct net_bridge_fdb_entry *, int);
32
33static u32 fdb_salt __read_mostly;
34
35int __init br_fdb_init(void)
36{
37 br_fdb_cache = kmem_cache_create("bridge_fdb_cache",
38 sizeof(struct net_bridge_fdb_entry),
39 0,
40 SLAB_HWCACHE_ALIGN, NULL);
41 if (!br_fdb_cache)
42 return -ENOMEM;
43
44 get_random_bytes(&fdb_salt, sizeof(fdb_salt));
45 return 0;
46}
47
48void br_fdb_fini(void)
49{
50 kmem_cache_destroy(br_fdb_cache);
51}
52
53
54/* if topology_changing then use forward_delay (default 15 sec)
55 * otherwise keep longer (default 5 minutes)
56 */
57static inline unsigned long hold_time(const struct net_bridge *br)
58{
59 return br->topology_change ? br->forward_delay : br->ageing_time;
60}
61
62static inline int has_expired(const struct net_bridge *br,
63 const struct net_bridge_fdb_entry *fdb)
64{
65 return !fdb->is_static &&
66 time_before_eq(fdb->updated + hold_time(br), jiffies);
67}
68
69static inline int br_mac_hash(const unsigned char *mac)
70{
71 /* use 1 byte of OUI cnd 3 bytes of NIC */
72 u32 key = get_unaligned((u32 *)(mac + 2));
73 return jhash_1word(key, fdb_salt) & (BR_HASH_SIZE - 1);
74}
75
76static void fdb_rcu_free(struct rcu_head *head)
77{
78 struct net_bridge_fdb_entry *ent
79 = container_of(head, struct net_bridge_fdb_entry, rcu);
80 kmem_cache_free(br_fdb_cache, ent);
81}
82
83static inline void fdb_delete(struct net_bridge_fdb_entry *f)
84{
85 fdb_notify(f, RTM_DELNEIGH);
86 hlist_del_rcu(&f->hlist);
87 call_rcu(&f->rcu, fdb_rcu_free);
88}
89
90void br_fdb_changeaddr(struct net_bridge_port *p, const unsigned char *newaddr)
91{
92 struct net_bridge *br = p->br;
93 int i;
94
95 spin_lock_bh(&br->hash_lock);
96
97 /* Search all chains since old address/hash is unknown */
98 for (i = 0; i < BR_HASH_SIZE; i++) {
99 struct hlist_node *h;
100 hlist_for_each(h, &br->hash[i]) {
101 struct net_bridge_fdb_entry *f;
102
103 f = hlist_entry(h, struct net_bridge_fdb_entry, hlist);
104 if (f->dst == p && f->is_local) {
105 /* maybe another port has same hw addr? */
106 struct net_bridge_port *op;
107 list_for_each_entry(op, &br->port_list, list) {
108 if (op != p &&
109 !compare_ether_addr(op->dev->dev_addr,
110 f->addr.addr)) {
111 f->dst = op;
112 goto insert;
113 }
114 }
115
116 /* delete old one */
117 fdb_delete(f);
118 goto insert;
119 }
120 }
121 }
122 insert:
123 /* insert new address, may fail if invalid address or dup. */
124 fdb_insert(br, p, newaddr);
125
126 spin_unlock_bh(&br->hash_lock);
127}
128
129void br_fdb_cleanup(unsigned long _data)
130{
131 struct net_bridge *br = (struct net_bridge *)_data;
132 unsigned long delay = hold_time(br);
133 unsigned long next_timer = jiffies + br->ageing_time;
134 int i;
135
136 spin_lock_bh(&br->hash_lock);
137 for (i = 0; i < BR_HASH_SIZE; i++) {
138 struct net_bridge_fdb_entry *f;
139 struct hlist_node *h, *n;
140
141 hlist_for_each_entry_safe(f, h, n, &br->hash[i], hlist) {
142 unsigned long this_timer;
143 if (f->is_static)
144 continue;
145 this_timer = f->updated + delay;
146 if (time_before_eq(this_timer, jiffies))
147 fdb_delete(f);
148 else if (time_before(this_timer, next_timer))
149 next_timer = this_timer;
150 }
151 }
152 spin_unlock_bh(&br->hash_lock);
153
154 mod_timer(&br->gc_timer, round_jiffies_up(next_timer));
155}
156
157/* Completely flush all dynamic entries in forwarding database.*/
158void br_fdb_flush(struct net_bridge *br)
159{
160 int i;
161
162 spin_lock_bh(&br->hash_lock);
163 for (i = 0; i < BR_HASH_SIZE; i++) {
164 struct net_bridge_fdb_entry *f;
165 struct hlist_node *h, *n;
166 hlist_for_each_entry_safe(f, h, n, &br->hash[i], hlist) {
167 if (!f->is_static)
168 fdb_delete(f);
169 }
170 }
171 spin_unlock_bh(&br->hash_lock);
172}
173
174/* Flush all entries referring to a specific port.
175 * if do_all is set also flush static entries
176 */
177void br_fdb_delete_by_port(struct net_bridge *br,
178 const struct net_bridge_port *p,
179 int do_all)
180{
181 int i;
182
183 spin_lock_bh(&br->hash_lock);
184 for (i = 0; i < BR_HASH_SIZE; i++) {
185 struct hlist_node *h, *g;
186
187 hlist_for_each_safe(h, g, &br->hash[i]) {
188 struct net_bridge_fdb_entry *f
189 = hlist_entry(h, struct net_bridge_fdb_entry, hlist);
190 if (f->dst != p)
191 continue;
192
193 if (f->is_static && !do_all)
194 continue;
195 /*
196 * if multiple ports all have the same device address
197 * then when one port is deleted, assign
198 * the local entry to other port
199 */
200 if (f->is_local) {
201 struct net_bridge_port *op;
202 list_for_each_entry(op, &br->port_list, list) {
203 if (op != p &&
204 !compare_ether_addr(op->dev->dev_addr,
205 f->addr.addr)) {
206 f->dst = op;
207 goto skip_delete;
208 }
209 }
210 }
211
212 fdb_delete(f);
213 skip_delete: ;
214 }
215 }
216 spin_unlock_bh(&br->hash_lock);
217}
218
219/* No locking or refcounting, assumes caller has rcu_read_lock */
220struct net_bridge_fdb_entry *__br_fdb_get(struct net_bridge *br,
221 const unsigned char *addr)
222{
223 struct hlist_node *h;
224 struct net_bridge_fdb_entry *fdb;
225
226 hlist_for_each_entry_rcu(fdb, h, &br->hash[br_mac_hash(addr)], hlist) {
227 if (!compare_ether_addr(fdb->addr.addr, addr)) {
228 if (unlikely(has_expired(br, fdb)))
229 break;
230 return fdb;
231 }
232 }
233
234 return NULL;
235}
236
237#if defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE)
238/* Interface used by ATM LANE hook to test
239 * if an addr is on some other bridge port */
240int br_fdb_test_addr(struct net_device *dev, unsigned char *addr)
241{
242 struct net_bridge_fdb_entry *fdb;
243 struct net_bridge_port *port;
244 int ret;
245
246 rcu_read_lock();
247 port = br_port_get_rcu(dev);
248 if (!port)
249 ret = 0;
250 else {
251 fdb = __br_fdb_get(port->br, addr);
252 ret = fdb && fdb->dst->dev != dev &&
253 fdb->dst->state == BR_STATE_FORWARDING;
254 }
255 rcu_read_unlock();
256
257 return ret;
258}
259#endif /* CONFIG_ATM_LANE */
260
261/*
262 * Fill buffer with forwarding table records in
263 * the API format.
264 */
265int br_fdb_fillbuf(struct net_bridge *br, void *buf,
266 unsigned long maxnum, unsigned long skip)
267{
268 struct __fdb_entry *fe = buf;
269 int i, num = 0;
270 struct hlist_node *h;
271 struct net_bridge_fdb_entry *f;
272
273 memset(buf, 0, maxnum*sizeof(struct __fdb_entry));
274
275 rcu_read_lock();
276 for (i = 0; i < BR_HASH_SIZE; i++) {
277 hlist_for_each_entry_rcu(f, h, &br->hash[i], hlist) {
278 if (num >= maxnum)
279 goto out;
280
281 if (has_expired(br, f))
282 continue;
283
284 if (skip) {
285 --skip;
286 continue;
287 }
288
289 /* convert from internal format to API */
290 memcpy(fe->mac_addr, f->addr.addr, ETH_ALEN);
291
292 /* due to ABI compat need to split into hi/lo */
293 fe->port_no = f->dst->port_no;
294 fe->port_hi = f->dst->port_no >> 8;
295
296 fe->is_local = f->is_local;
297 if (!f->is_static)
298 fe->ageing_timer_value = jiffies_to_clock_t(jiffies - f->updated);
299 ++fe;
300 ++num;
301 }
302 }
303
304 out:
305 rcu_read_unlock();
306
307 return num;
308}
309
310static struct net_bridge_fdb_entry *fdb_find(struct hlist_head *head,
311 const unsigned char *addr)
312{
313 struct hlist_node *h;
314 struct net_bridge_fdb_entry *fdb;
315
316 hlist_for_each_entry(fdb, h, head, hlist) {
317 if (!compare_ether_addr(fdb->addr.addr, addr))
318 return fdb;
319 }
320 return NULL;
321}
322
323static struct net_bridge_fdb_entry *fdb_find_rcu(struct hlist_head *head,
324 const unsigned char *addr)
325{
326 struct hlist_node *h;
327 struct net_bridge_fdb_entry *fdb;
328
329 hlist_for_each_entry_rcu(fdb, h, head, hlist) {
330 if (!compare_ether_addr(fdb->addr.addr, addr))
331 return fdb;
332 }
333 return NULL;
334}
335
336static struct net_bridge_fdb_entry *fdb_create(struct hlist_head *head,
337 struct net_bridge_port *source,
338 const unsigned char *addr)
339{
340 struct net_bridge_fdb_entry *fdb;
341
342 fdb = kmem_cache_alloc(br_fdb_cache, GFP_ATOMIC);
343 if (fdb) {
344 memcpy(fdb->addr.addr, addr, ETH_ALEN);
345 fdb->dst = source;
346 fdb->is_local = 0;
347 fdb->is_static = 0;
348 fdb->updated = fdb->used = jiffies;
349 hlist_add_head_rcu(&fdb->hlist, head);
350 fdb_notify(fdb, RTM_NEWNEIGH);
351 }
352 return fdb;
353}
354
355static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
356 const unsigned char *addr)
357{
358 struct hlist_head *head = &br->hash[br_mac_hash(addr)];
359 struct net_bridge_fdb_entry *fdb;
360
361 if (!is_valid_ether_addr(addr))
362 return -EINVAL;
363
364 fdb = fdb_find(head, addr);
365 if (fdb) {
366 /* it is okay to have multiple ports with same
367 * address, just use the first one.
368 */
369 if (fdb->is_local)
370 return 0;
371 br_warn(br, "adding interface %s with same address "
372 "as a received packet\n",
373 source->dev->name);
374 fdb_delete(fdb);
375 }
376
377 fdb = fdb_create(head, source, addr);
378 if (!fdb)
379 return -ENOMEM;
380
381 fdb->is_local = fdb->is_static = 1;
382 return 0;
383}
384
385/* Add entry for local address of interface */
386int br_fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
387 const unsigned char *addr)
388{
389 int ret;
390
391 spin_lock_bh(&br->hash_lock);
392 ret = fdb_insert(br, source, addr);
393 spin_unlock_bh(&br->hash_lock);
394 return ret;
395}
396
397void br_fdb_update(struct net_bridge *br, struct net_bridge_port *source,
398 const unsigned char *addr)
399{
400 struct hlist_head *head = &br->hash[br_mac_hash(addr)];
401 struct net_bridge_fdb_entry *fdb;
402
403 /* some users want to always flood. */
404 if (hold_time(br) == 0)
405 return;
406
407 /* ignore packets unless we are using this port */
408 if (!(source->state == BR_STATE_LEARNING ||
409 source->state == BR_STATE_FORWARDING))
410 return;
411
412 fdb = fdb_find_rcu(head, addr);
413 if (likely(fdb)) {
414 /* attempt to update an entry for a local interface */
415 if (unlikely(fdb->is_local)) {
416 if (net_ratelimit())
417 br_warn(br, "received packet on %s with "
418 "own address as source address\n",
419 source->dev->name);
420 } else {
421 /* fastpath: update of existing entry */
422 fdb->dst = source;
423 fdb->updated = jiffies;
424 }
425 } else {
426 spin_lock(&br->hash_lock);
427 if (likely(!fdb_find(head, addr)))
428 fdb_create(head, source, addr);
429
430 /* else we lose race and someone else inserts
431 * it first, don't bother updating
432 */
433 spin_unlock(&br->hash_lock);
434 }
435}
436
437static int fdb_to_nud(const struct net_bridge_fdb_entry *fdb)
438{
439 if (fdb->is_local)
440 return NUD_PERMANENT;
441 else if (fdb->is_static)
442 return NUD_NOARP;
443 else if (has_expired(fdb->dst->br, fdb))
444 return NUD_STALE;
445 else
446 return NUD_REACHABLE;
447}
448
449static int fdb_fill_info(struct sk_buff *skb,
450 const struct net_bridge_fdb_entry *fdb,
451 u32 pid, u32 seq, int type, unsigned int flags)
452{
453 unsigned long now = jiffies;
454 struct nda_cacheinfo ci;
455 struct nlmsghdr *nlh;
456 struct ndmsg *ndm;
457
458 nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ndm), flags);
459 if (nlh == NULL)
460 return -EMSGSIZE;
461
462
463 ndm = nlmsg_data(nlh);
464 ndm->ndm_family = AF_BRIDGE;
465 ndm->ndm_pad1 = 0;
466 ndm->ndm_pad2 = 0;
467 ndm->ndm_flags = 0;
468 ndm->ndm_type = 0;
469 ndm->ndm_ifindex = fdb->dst->dev->ifindex;
470 ndm->ndm_state = fdb_to_nud(fdb);
471
472 NLA_PUT(skb, NDA_LLADDR, ETH_ALEN, &fdb->addr);
473
474 ci.ndm_used = jiffies_to_clock_t(now - fdb->used);
475 ci.ndm_confirmed = 0;
476 ci.ndm_updated = jiffies_to_clock_t(now - fdb->updated);
477 ci.ndm_refcnt = 0;
478 NLA_PUT(skb, NDA_CACHEINFO, sizeof(ci), &ci);
479
480 return nlmsg_end(skb, nlh);
481
482nla_put_failure:
483 nlmsg_cancel(skb, nlh);
484 return -EMSGSIZE;
485}
486
487static inline size_t fdb_nlmsg_size(void)
488{
489 return NLMSG_ALIGN(sizeof(struct ndmsg))
490 + nla_total_size(ETH_ALEN) /* NDA_LLADDR */
491 + nla_total_size(sizeof(struct nda_cacheinfo));
492}
493
494static void fdb_notify(const struct net_bridge_fdb_entry *fdb, int type)
495{
496 struct net *net = dev_net(fdb->dst->dev);
497 struct sk_buff *skb;
498 int err = -ENOBUFS;
499
500 skb = nlmsg_new(fdb_nlmsg_size(), GFP_ATOMIC);
501 if (skb == NULL)
502 goto errout;
503
504 err = fdb_fill_info(skb, fdb, 0, 0, type, 0);
505 if (err < 0) {
506 /* -EMSGSIZE implies BUG in fdb_nlmsg_size() */
507 WARN_ON(err == -EMSGSIZE);
508 kfree_skb(skb);
509 goto errout;
510 }
511 rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
512 return;
513errout:
514 if (err < 0)
515 rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
516}
517
518/* Dump information about entries, in response to GETNEIGH */
519int br_fdb_dump(struct sk_buff *skb, struct netlink_callback *cb)
520{
521 struct net *net = sock_net(skb->sk);
522 struct net_device *dev;
523 int idx = 0;
524
525 rcu_read_lock();
526 for_each_netdev_rcu(net, dev) {
527 struct net_bridge *br = netdev_priv(dev);
528 int i;
529
530 if (!(dev->priv_flags & IFF_EBRIDGE))
531 continue;
532
533 for (i = 0; i < BR_HASH_SIZE; i++) {
534 struct hlist_node *h;
535 struct net_bridge_fdb_entry *f;
536
537 hlist_for_each_entry_rcu(f, h, &br->hash[i], hlist) {
538 if (idx < cb->args[0])
539 goto skip;
540
541 if (fdb_fill_info(skb, f,
542 NETLINK_CB(cb->skb).pid,
543 cb->nlh->nlmsg_seq,
544 RTM_NEWNEIGH,
545 NLM_F_MULTI) < 0)
546 break;
547skip:
548 ++idx;
549 }
550 }
551 }
552 rcu_read_unlock();
553
554 cb->args[0] = idx;
555
556 return skb->len;
557}
558
559/* Create new static fdb entry */
560static int fdb_add_entry(struct net_bridge_port *source, const __u8 *addr,
561 __u16 state)
562{
563 struct net_bridge *br = source->br;
564 struct hlist_head *head = &br->hash[br_mac_hash(addr)];
565 struct net_bridge_fdb_entry *fdb;
566
567 fdb = fdb_find(head, addr);
568 if (fdb)
569 return -EEXIST;
570
571 fdb = fdb_create(head, source, addr);
572 if (!fdb)
573 return -ENOMEM;
574
575 if (state & NUD_PERMANENT)
576 fdb->is_local = fdb->is_static = 1;
577 else if (state & NUD_NOARP)
578 fdb->is_static = 1;
579 return 0;
580}
581
582/* Add new permanent fdb entry with RTM_NEWNEIGH */
583int br_fdb_add(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
584{
585 struct net *net = sock_net(skb->sk);
586 struct ndmsg *ndm;
587 struct nlattr *tb[NDA_MAX+1];
588 struct net_device *dev;
589 struct net_bridge_port *p;
590 const __u8 *addr;
591 int err;
592
593 ASSERT_RTNL();
594 err = nlmsg_parse(nlh, sizeof(*ndm), tb, NDA_MAX, NULL);
595 if (err < 0)
596 return err;
597
598 ndm = nlmsg_data(nlh);
599 if (ndm->ndm_ifindex == 0) {
600 pr_info("bridge: RTM_NEWNEIGH with invalid ifindex\n");
601 return -EINVAL;
602 }
603
604 dev = __dev_get_by_index(net, ndm->ndm_ifindex);
605 if (dev == NULL) {
606 pr_info("bridge: RTM_NEWNEIGH with unknown ifindex\n");
607 return -ENODEV;
608 }
609
610 if (!tb[NDA_LLADDR] || nla_len(tb[NDA_LLADDR]) != ETH_ALEN) {
611 pr_info("bridge: RTM_NEWNEIGH with invalid address\n");
612 return -EINVAL;
613 }
614
615 addr = nla_data(tb[NDA_LLADDR]);
616 if (!is_valid_ether_addr(addr)) {
617 pr_info("bridge: RTM_NEWNEIGH with invalid ether address\n");
618 return -EINVAL;
619 }
620
621 p = br_port_get_rtnl(dev);
622 if (p == NULL) {
623 pr_info("bridge: RTM_NEWNEIGH %s not a bridge port\n",
624 dev->name);
625 return -EINVAL;
626 }
627
628 spin_lock_bh(&p->br->hash_lock);
629 err = fdb_add_entry(p, addr, ndm->ndm_state);
630 spin_unlock_bh(&p->br->hash_lock);
631
632 return err;
633}
634
635static int fdb_delete_by_addr(struct net_bridge_port *p, const u8 *addr)
636{
637 struct net_bridge *br = p->br;
638 struct hlist_head *head = &br->hash[br_mac_hash(addr)];
639 struct net_bridge_fdb_entry *fdb;
640
641 fdb = fdb_find(head, addr);
642 if (!fdb)
643 return -ENOENT;
644
645 fdb_delete(fdb);
646 return 0;
647}
648
649/* Remove neighbor entry with RTM_DELNEIGH */
650int br_fdb_delete(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
651{
652 struct net *net = sock_net(skb->sk);
653 struct ndmsg *ndm;
654 struct net_bridge_port *p;
655 struct nlattr *llattr;
656 const __u8 *addr;
657 struct net_device *dev;
658 int err;
659
660 ASSERT_RTNL();
661 if (nlmsg_len(nlh) < sizeof(*ndm))
662 return -EINVAL;
663
664 ndm = nlmsg_data(nlh);
665 if (ndm->ndm_ifindex == 0) {
666 pr_info("bridge: RTM_DELNEIGH with invalid ifindex\n");
667 return -EINVAL;
668 }
669
670 dev = __dev_get_by_index(net, ndm->ndm_ifindex);
671 if (dev == NULL) {
672 pr_info("bridge: RTM_DELNEIGH with unknown ifindex\n");
673 return -ENODEV;
674 }
675
676 llattr = nlmsg_find_attr(nlh, sizeof(*ndm), NDA_LLADDR);
677 if (llattr == NULL || nla_len(llattr) != ETH_ALEN) {
678 pr_info("bridge: RTM_DELNEIGH with invalid address\n");
679 return -EINVAL;
680 }
681
682 addr = nla_data(llattr);
683
684 p = br_port_get_rtnl(dev);
685 if (p == NULL) {
686 pr_info("bridge: RTM_DELNEIGH %s not a bridge port\n",
687 dev->name);
688 return -EINVAL;
689 }
690
691 spin_lock_bh(&p->br->hash_lock);
692 err = fdb_delete_by_addr(p, addr);
693 spin_unlock_bh(&p->br->hash_lock);
694
695 return err;
696}
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Forwarding database
4 * Linux ethernet bridge
5 *
6 * Authors:
7 * Lennert Buytenhek <buytenh@gnu.org>
8 */
9
10#include <linux/kernel.h>
11#include <linux/init.h>
12#include <linux/rculist.h>
13#include <linux/spinlock.h>
14#include <linux/times.h>
15#include <linux/netdevice.h>
16#include <linux/etherdevice.h>
17#include <linux/jhash.h>
18#include <linux/random.h>
19#include <linux/slab.h>
20#include <linux/atomic.h>
21#include <asm/unaligned.h>
22#include <linux/if_vlan.h>
23#include <net/switchdev.h>
24#include <trace/events/bridge.h>
25#include "br_private.h"
26
27static const struct rhashtable_params br_fdb_rht_params = {
28 .head_offset = offsetof(struct net_bridge_fdb_entry, rhnode),
29 .key_offset = offsetof(struct net_bridge_fdb_entry, key),
30 .key_len = sizeof(struct net_bridge_fdb_key),
31 .automatic_shrinking = true,
32};
33
34static struct kmem_cache *br_fdb_cache __read_mostly;
35static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
36 const unsigned char *addr, u16 vid);
37static void fdb_notify(struct net_bridge *br,
38 const struct net_bridge_fdb_entry *, int, bool);
39
40int __init br_fdb_init(void)
41{
42 br_fdb_cache = kmem_cache_create("bridge_fdb_cache",
43 sizeof(struct net_bridge_fdb_entry),
44 0,
45 SLAB_HWCACHE_ALIGN, NULL);
46 if (!br_fdb_cache)
47 return -ENOMEM;
48
49 return 0;
50}
51
52void br_fdb_fini(void)
53{
54 kmem_cache_destroy(br_fdb_cache);
55}
56
57int br_fdb_hash_init(struct net_bridge *br)
58{
59 return rhashtable_init(&br->fdb_hash_tbl, &br_fdb_rht_params);
60}
61
62void br_fdb_hash_fini(struct net_bridge *br)
63{
64 rhashtable_destroy(&br->fdb_hash_tbl);
65}
66
67/* if topology_changing then use forward_delay (default 15 sec)
68 * otherwise keep longer (default 5 minutes)
69 */
70static inline unsigned long hold_time(const struct net_bridge *br)
71{
72 return br->topology_change ? br->forward_delay : br->ageing_time;
73}
74
75static inline int has_expired(const struct net_bridge *br,
76 const struct net_bridge_fdb_entry *fdb)
77{
78 return !test_bit(BR_FDB_STATIC, &fdb->flags) &&
79 !test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags) &&
80 time_before_eq(fdb->updated + hold_time(br), jiffies);
81}
82
83static void fdb_rcu_free(struct rcu_head *head)
84{
85 struct net_bridge_fdb_entry *ent
86 = container_of(head, struct net_bridge_fdb_entry, rcu);
87 kmem_cache_free(br_fdb_cache, ent);
88}
89
90static struct net_bridge_fdb_entry *fdb_find_rcu(struct rhashtable *tbl,
91 const unsigned char *addr,
92 __u16 vid)
93{
94 struct net_bridge_fdb_key key;
95
96 WARN_ON_ONCE(!rcu_read_lock_held());
97
98 key.vlan_id = vid;
99 memcpy(key.addr.addr, addr, sizeof(key.addr.addr));
100
101 return rhashtable_lookup(tbl, &key, br_fdb_rht_params);
102}
103
104/* requires bridge hash_lock */
105static struct net_bridge_fdb_entry *br_fdb_find(struct net_bridge *br,
106 const unsigned char *addr,
107 __u16 vid)
108{
109 struct net_bridge_fdb_entry *fdb;
110
111 lockdep_assert_held_once(&br->hash_lock);
112
113 rcu_read_lock();
114 fdb = fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
115 rcu_read_unlock();
116
117 return fdb;
118}
119
120struct net_device *br_fdb_find_port(const struct net_device *br_dev,
121 const unsigned char *addr,
122 __u16 vid)
123{
124 struct net_bridge_fdb_entry *f;
125 struct net_device *dev = NULL;
126 struct net_bridge *br;
127
128 ASSERT_RTNL();
129
130 if (!netif_is_bridge_master(br_dev))
131 return NULL;
132
133 br = netdev_priv(br_dev);
134 rcu_read_lock();
135 f = br_fdb_find_rcu(br, addr, vid);
136 if (f && f->dst)
137 dev = f->dst->dev;
138 rcu_read_unlock();
139
140 return dev;
141}
142EXPORT_SYMBOL_GPL(br_fdb_find_port);
143
144struct net_bridge_fdb_entry *br_fdb_find_rcu(struct net_bridge *br,
145 const unsigned char *addr,
146 __u16 vid)
147{
148 return fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
149}
150
151/* When a static FDB entry is added, the mac address from the entry is
152 * added to the bridge private HW address list and all required ports
153 * are then updated with the new information.
154 * Called under RTNL.
155 */
156static void fdb_add_hw_addr(struct net_bridge *br, const unsigned char *addr)
157{
158 int err;
159 struct net_bridge_port *p;
160
161 ASSERT_RTNL();
162
163 list_for_each_entry(p, &br->port_list, list) {
164 if (!br_promisc_port(p)) {
165 err = dev_uc_add(p->dev, addr);
166 if (err)
167 goto undo;
168 }
169 }
170
171 return;
172undo:
173 list_for_each_entry_continue_reverse(p, &br->port_list, list) {
174 if (!br_promisc_port(p))
175 dev_uc_del(p->dev, addr);
176 }
177}
178
179/* When a static FDB entry is deleted, the HW address from that entry is
180 * also removed from the bridge private HW address list and updates all
181 * the ports with needed information.
182 * Called under RTNL.
183 */
184static void fdb_del_hw_addr(struct net_bridge *br, const unsigned char *addr)
185{
186 struct net_bridge_port *p;
187
188 ASSERT_RTNL();
189
190 list_for_each_entry(p, &br->port_list, list) {
191 if (!br_promisc_port(p))
192 dev_uc_del(p->dev, addr);
193 }
194}
195
196static void fdb_delete(struct net_bridge *br, struct net_bridge_fdb_entry *f,
197 bool swdev_notify)
198{
199 trace_fdb_delete(br, f);
200
201 if (test_bit(BR_FDB_STATIC, &f->flags))
202 fdb_del_hw_addr(br, f->key.addr.addr);
203
204 hlist_del_init_rcu(&f->fdb_node);
205 rhashtable_remove_fast(&br->fdb_hash_tbl, &f->rhnode,
206 br_fdb_rht_params);
207 fdb_notify(br, f, RTM_DELNEIGH, swdev_notify);
208 call_rcu(&f->rcu, fdb_rcu_free);
209}
210
211/* Delete a local entry if no other port had the same address. */
212static void fdb_delete_local(struct net_bridge *br,
213 const struct net_bridge_port *p,
214 struct net_bridge_fdb_entry *f)
215{
216 const unsigned char *addr = f->key.addr.addr;
217 struct net_bridge_vlan_group *vg;
218 const struct net_bridge_vlan *v;
219 struct net_bridge_port *op;
220 u16 vid = f->key.vlan_id;
221
222 /* Maybe another port has same hw addr? */
223 list_for_each_entry(op, &br->port_list, list) {
224 vg = nbp_vlan_group(op);
225 if (op != p && ether_addr_equal(op->dev->dev_addr, addr) &&
226 (!vid || br_vlan_find(vg, vid))) {
227 f->dst = op;
228 clear_bit(BR_FDB_ADDED_BY_USER, &f->flags);
229 return;
230 }
231 }
232
233 vg = br_vlan_group(br);
234 v = br_vlan_find(vg, vid);
235 /* Maybe bridge device has same hw addr? */
236 if (p && ether_addr_equal(br->dev->dev_addr, addr) &&
237 (!vid || (v && br_vlan_should_use(v)))) {
238 f->dst = NULL;
239 clear_bit(BR_FDB_ADDED_BY_USER, &f->flags);
240 return;
241 }
242
243 fdb_delete(br, f, true);
244}
245
246void br_fdb_find_delete_local(struct net_bridge *br,
247 const struct net_bridge_port *p,
248 const unsigned char *addr, u16 vid)
249{
250 struct net_bridge_fdb_entry *f;
251
252 spin_lock_bh(&br->hash_lock);
253 f = br_fdb_find(br, addr, vid);
254 if (f && test_bit(BR_FDB_LOCAL, &f->flags) &&
255 !test_bit(BR_FDB_ADDED_BY_USER, &f->flags) && f->dst == p)
256 fdb_delete_local(br, p, f);
257 spin_unlock_bh(&br->hash_lock);
258}
259
260void br_fdb_changeaddr(struct net_bridge_port *p, const unsigned char *newaddr)
261{
262 struct net_bridge_vlan_group *vg;
263 struct net_bridge_fdb_entry *f;
264 struct net_bridge *br = p->br;
265 struct net_bridge_vlan *v;
266
267 spin_lock_bh(&br->hash_lock);
268 vg = nbp_vlan_group(p);
269 hlist_for_each_entry(f, &br->fdb_list, fdb_node) {
270 if (f->dst == p && test_bit(BR_FDB_LOCAL, &f->flags) &&
271 !test_bit(BR_FDB_ADDED_BY_USER, &f->flags)) {
272 /* delete old one */
273 fdb_delete_local(br, p, f);
274
275 /* if this port has no vlan information
276 * configured, we can safely be done at
277 * this point.
278 */
279 if (!vg || !vg->num_vlans)
280 goto insert;
281 }
282 }
283
284insert:
285 /* insert new address, may fail if invalid address or dup. */
286 fdb_insert(br, p, newaddr, 0);
287
288 if (!vg || !vg->num_vlans)
289 goto done;
290
291 /* Now add entries for every VLAN configured on the port.
292 * This function runs under RTNL so the bitmap will not change
293 * from under us.
294 */
295 list_for_each_entry(v, &vg->vlan_list, vlist)
296 fdb_insert(br, p, newaddr, v->vid);
297
298done:
299 spin_unlock_bh(&br->hash_lock);
300}
301
302void br_fdb_change_mac_address(struct net_bridge *br, const u8 *newaddr)
303{
304 struct net_bridge_vlan_group *vg;
305 struct net_bridge_fdb_entry *f;
306 struct net_bridge_vlan *v;
307
308 spin_lock_bh(&br->hash_lock);
309
310 /* If old entry was unassociated with any port, then delete it. */
311 f = br_fdb_find(br, br->dev->dev_addr, 0);
312 if (f && test_bit(BR_FDB_LOCAL, &f->flags) &&
313 !f->dst && !test_bit(BR_FDB_ADDED_BY_USER, &f->flags))
314 fdb_delete_local(br, NULL, f);
315
316 fdb_insert(br, NULL, newaddr, 0);
317 vg = br_vlan_group(br);
318 if (!vg || !vg->num_vlans)
319 goto out;
320 /* Now remove and add entries for every VLAN configured on the
321 * bridge. This function runs under RTNL so the bitmap will not
322 * change from under us.
323 */
324 list_for_each_entry(v, &vg->vlan_list, vlist) {
325 if (!br_vlan_should_use(v))
326 continue;
327 f = br_fdb_find(br, br->dev->dev_addr, v->vid);
328 if (f && test_bit(BR_FDB_LOCAL, &f->flags) &&
329 !f->dst && !test_bit(BR_FDB_ADDED_BY_USER, &f->flags))
330 fdb_delete_local(br, NULL, f);
331 fdb_insert(br, NULL, newaddr, v->vid);
332 }
333out:
334 spin_unlock_bh(&br->hash_lock);
335}
336
337void br_fdb_cleanup(struct work_struct *work)
338{
339 struct net_bridge *br = container_of(work, struct net_bridge,
340 gc_work.work);
341 struct net_bridge_fdb_entry *f = NULL;
342 unsigned long delay = hold_time(br);
343 unsigned long work_delay = delay;
344 unsigned long now = jiffies;
345
346 /* this part is tricky, in order to avoid blocking learning and
347 * consequently forwarding, we rely on rcu to delete objects with
348 * delayed freeing allowing us to continue traversing
349 */
350 rcu_read_lock();
351 hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
352 unsigned long this_timer = f->updated + delay;
353
354 if (test_bit(BR_FDB_STATIC, &f->flags) ||
355 test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &f->flags)) {
356 if (test_bit(BR_FDB_NOTIFY, &f->flags)) {
357 if (time_after(this_timer, now))
358 work_delay = min(work_delay,
359 this_timer - now);
360 else if (!test_and_set_bit(BR_FDB_NOTIFY_INACTIVE,
361 &f->flags))
362 fdb_notify(br, f, RTM_NEWNEIGH, false);
363 }
364 continue;
365 }
366
367 if (time_after(this_timer, now)) {
368 work_delay = min(work_delay, this_timer - now);
369 } else {
370 spin_lock_bh(&br->hash_lock);
371 if (!hlist_unhashed(&f->fdb_node))
372 fdb_delete(br, f, true);
373 spin_unlock_bh(&br->hash_lock);
374 }
375 }
376 rcu_read_unlock();
377
378 /* Cleanup minimum 10 milliseconds apart */
379 work_delay = max_t(unsigned long, work_delay, msecs_to_jiffies(10));
380 mod_delayed_work(system_long_wq, &br->gc_work, work_delay);
381}
382
383/* Completely flush all dynamic entries in forwarding database.*/
384void br_fdb_flush(struct net_bridge *br)
385{
386 struct net_bridge_fdb_entry *f;
387 struct hlist_node *tmp;
388
389 spin_lock_bh(&br->hash_lock);
390 hlist_for_each_entry_safe(f, tmp, &br->fdb_list, fdb_node) {
391 if (!test_bit(BR_FDB_STATIC, &f->flags))
392 fdb_delete(br, f, true);
393 }
394 spin_unlock_bh(&br->hash_lock);
395}
396
397/* Flush all entries referring to a specific port.
398 * if do_all is set also flush static entries
399 * if vid is set delete all entries that match the vlan_id
400 */
401void br_fdb_delete_by_port(struct net_bridge *br,
402 const struct net_bridge_port *p,
403 u16 vid,
404 int do_all)
405{
406 struct net_bridge_fdb_entry *f;
407 struct hlist_node *tmp;
408
409 spin_lock_bh(&br->hash_lock);
410 hlist_for_each_entry_safe(f, tmp, &br->fdb_list, fdb_node) {
411 if (f->dst != p)
412 continue;
413
414 if (!do_all)
415 if (test_bit(BR_FDB_STATIC, &f->flags) ||
416 (test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &f->flags) &&
417 !test_bit(BR_FDB_OFFLOADED, &f->flags)) ||
418 (vid && f->key.vlan_id != vid))
419 continue;
420
421 if (test_bit(BR_FDB_LOCAL, &f->flags))
422 fdb_delete_local(br, p, f);
423 else
424 fdb_delete(br, f, true);
425 }
426 spin_unlock_bh(&br->hash_lock);
427}
428
429#if IS_ENABLED(CONFIG_ATM_LANE)
430/* Interface used by ATM LANE hook to test
431 * if an addr is on some other bridge port */
432int br_fdb_test_addr(struct net_device *dev, unsigned char *addr)
433{
434 struct net_bridge_fdb_entry *fdb;
435 struct net_bridge_port *port;
436 int ret;
437
438 rcu_read_lock();
439 port = br_port_get_rcu(dev);
440 if (!port)
441 ret = 0;
442 else {
443 fdb = br_fdb_find_rcu(port->br, addr, 0);
444 ret = fdb && fdb->dst && fdb->dst->dev != dev &&
445 fdb->dst->state == BR_STATE_FORWARDING;
446 }
447 rcu_read_unlock();
448
449 return ret;
450}
451#endif /* CONFIG_ATM_LANE */
452
453/*
454 * Fill buffer with forwarding table records in
455 * the API format.
456 */
457int br_fdb_fillbuf(struct net_bridge *br, void *buf,
458 unsigned long maxnum, unsigned long skip)
459{
460 struct net_bridge_fdb_entry *f;
461 struct __fdb_entry *fe = buf;
462 int num = 0;
463
464 memset(buf, 0, maxnum*sizeof(struct __fdb_entry));
465
466 rcu_read_lock();
467 hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
468 if (num >= maxnum)
469 break;
470
471 if (has_expired(br, f))
472 continue;
473
474 /* ignore pseudo entry for local MAC address */
475 if (!f->dst)
476 continue;
477
478 if (skip) {
479 --skip;
480 continue;
481 }
482
483 /* convert from internal format to API */
484 memcpy(fe->mac_addr, f->key.addr.addr, ETH_ALEN);
485
486 /* due to ABI compat need to split into hi/lo */
487 fe->port_no = f->dst->port_no;
488 fe->port_hi = f->dst->port_no >> 8;
489
490 fe->is_local = test_bit(BR_FDB_LOCAL, &f->flags);
491 if (!test_bit(BR_FDB_STATIC, &f->flags))
492 fe->ageing_timer_value = jiffies_delta_to_clock_t(jiffies - f->updated);
493 ++fe;
494 ++num;
495 }
496 rcu_read_unlock();
497
498 return num;
499}
500
501static struct net_bridge_fdb_entry *fdb_create(struct net_bridge *br,
502 struct net_bridge_port *source,
503 const unsigned char *addr,
504 __u16 vid,
505 unsigned long flags)
506{
507 struct net_bridge_fdb_entry *fdb;
508
509 fdb = kmem_cache_alloc(br_fdb_cache, GFP_ATOMIC);
510 if (fdb) {
511 memcpy(fdb->key.addr.addr, addr, ETH_ALEN);
512 fdb->dst = source;
513 fdb->key.vlan_id = vid;
514 fdb->flags = flags;
515 fdb->updated = fdb->used = jiffies;
516 if (rhashtable_lookup_insert_fast(&br->fdb_hash_tbl,
517 &fdb->rhnode,
518 br_fdb_rht_params)) {
519 kmem_cache_free(br_fdb_cache, fdb);
520 fdb = NULL;
521 } else {
522 hlist_add_head_rcu(&fdb->fdb_node, &br->fdb_list);
523 }
524 }
525 return fdb;
526}
527
528static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
529 const unsigned char *addr, u16 vid)
530{
531 struct net_bridge_fdb_entry *fdb;
532
533 if (!is_valid_ether_addr(addr))
534 return -EINVAL;
535
536 fdb = br_fdb_find(br, addr, vid);
537 if (fdb) {
538 /* it is okay to have multiple ports with same
539 * address, just use the first one.
540 */
541 if (test_bit(BR_FDB_LOCAL, &fdb->flags))
542 return 0;
543 br_warn(br, "adding interface %s with same address as a received packet (addr:%pM, vlan:%u)\n",
544 source ? source->dev->name : br->dev->name, addr, vid);
545 fdb_delete(br, fdb, true);
546 }
547
548 fdb = fdb_create(br, source, addr, vid,
549 BIT(BR_FDB_LOCAL) | BIT(BR_FDB_STATIC));
550 if (!fdb)
551 return -ENOMEM;
552
553 fdb_add_hw_addr(br, addr);
554 fdb_notify(br, fdb, RTM_NEWNEIGH, true);
555 return 0;
556}
557
558/* Add entry for local address of interface */
559int br_fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
560 const unsigned char *addr, u16 vid)
561{
562 int ret;
563
564 spin_lock_bh(&br->hash_lock);
565 ret = fdb_insert(br, source, addr, vid);
566 spin_unlock_bh(&br->hash_lock);
567 return ret;
568}
569
570/* returns true if the fdb was modified */
571static bool __fdb_mark_active(struct net_bridge_fdb_entry *fdb)
572{
573 return !!(test_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags) &&
574 test_and_clear_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags));
575}
576
577void br_fdb_update(struct net_bridge *br, struct net_bridge_port *source,
578 const unsigned char *addr, u16 vid, unsigned long flags)
579{
580 struct net_bridge_fdb_entry *fdb;
581
582 /* some users want to always flood. */
583 if (hold_time(br) == 0)
584 return;
585
586 fdb = fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
587 if (likely(fdb)) {
588 /* attempt to update an entry for a local interface */
589 if (unlikely(test_bit(BR_FDB_LOCAL, &fdb->flags))) {
590 if (net_ratelimit())
591 br_warn(br, "received packet on %s with own address as source address (addr:%pM, vlan:%u)\n",
592 source->dev->name, addr, vid);
593 } else {
594 unsigned long now = jiffies;
595 bool fdb_modified = false;
596
597 if (now != fdb->updated) {
598 fdb->updated = now;
599 fdb_modified = __fdb_mark_active(fdb);
600 }
601
602 /* fastpath: update of existing entry */
603 if (unlikely(source != fdb->dst &&
604 !test_bit(BR_FDB_STICKY, &fdb->flags))) {
605 fdb->dst = source;
606 fdb_modified = true;
607 /* Take over HW learned entry */
608 if (unlikely(test_bit(BR_FDB_ADDED_BY_EXT_LEARN,
609 &fdb->flags)))
610 clear_bit(BR_FDB_ADDED_BY_EXT_LEARN,
611 &fdb->flags);
612 }
613
614 if (unlikely(test_bit(BR_FDB_ADDED_BY_USER, &flags)))
615 set_bit(BR_FDB_ADDED_BY_USER, &fdb->flags);
616 if (unlikely(fdb_modified)) {
617 trace_br_fdb_update(br, source, addr, vid, flags);
618 fdb_notify(br, fdb, RTM_NEWNEIGH, true);
619 }
620 }
621 } else {
622 spin_lock(&br->hash_lock);
623 fdb = fdb_create(br, source, addr, vid, flags);
624 if (fdb) {
625 trace_br_fdb_update(br, source, addr, vid, flags);
626 fdb_notify(br, fdb, RTM_NEWNEIGH, true);
627 }
628 /* else we lose race and someone else inserts
629 * it first, don't bother updating
630 */
631 spin_unlock(&br->hash_lock);
632 }
633}
634
635static int fdb_to_nud(const struct net_bridge *br,
636 const struct net_bridge_fdb_entry *fdb)
637{
638 if (test_bit(BR_FDB_LOCAL, &fdb->flags))
639 return NUD_PERMANENT;
640 else if (test_bit(BR_FDB_STATIC, &fdb->flags))
641 return NUD_NOARP;
642 else if (has_expired(br, fdb))
643 return NUD_STALE;
644 else
645 return NUD_REACHABLE;
646}
647
648static int fdb_fill_info(struct sk_buff *skb, const struct net_bridge *br,
649 const struct net_bridge_fdb_entry *fdb,
650 u32 portid, u32 seq, int type, unsigned int flags)
651{
652 unsigned long now = jiffies;
653 struct nda_cacheinfo ci;
654 struct nlmsghdr *nlh;
655 struct ndmsg *ndm;
656
657 nlh = nlmsg_put(skb, portid, seq, type, sizeof(*ndm), flags);
658 if (nlh == NULL)
659 return -EMSGSIZE;
660
661 ndm = nlmsg_data(nlh);
662 ndm->ndm_family = AF_BRIDGE;
663 ndm->ndm_pad1 = 0;
664 ndm->ndm_pad2 = 0;
665 ndm->ndm_flags = 0;
666 ndm->ndm_type = 0;
667 ndm->ndm_ifindex = fdb->dst ? fdb->dst->dev->ifindex : br->dev->ifindex;
668 ndm->ndm_state = fdb_to_nud(br, fdb);
669
670 if (test_bit(BR_FDB_OFFLOADED, &fdb->flags))
671 ndm->ndm_flags |= NTF_OFFLOADED;
672 if (test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags))
673 ndm->ndm_flags |= NTF_EXT_LEARNED;
674 if (test_bit(BR_FDB_STICKY, &fdb->flags))
675 ndm->ndm_flags |= NTF_STICKY;
676
677 if (nla_put(skb, NDA_LLADDR, ETH_ALEN, &fdb->key.addr))
678 goto nla_put_failure;
679 if (nla_put_u32(skb, NDA_MASTER, br->dev->ifindex))
680 goto nla_put_failure;
681 ci.ndm_used = jiffies_to_clock_t(now - fdb->used);
682 ci.ndm_confirmed = 0;
683 ci.ndm_updated = jiffies_to_clock_t(now - fdb->updated);
684 ci.ndm_refcnt = 0;
685 if (nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci))
686 goto nla_put_failure;
687
688 if (fdb->key.vlan_id && nla_put(skb, NDA_VLAN, sizeof(u16),
689 &fdb->key.vlan_id))
690 goto nla_put_failure;
691
692 if (test_bit(BR_FDB_NOTIFY, &fdb->flags)) {
693 struct nlattr *nest = nla_nest_start(skb, NDA_FDB_EXT_ATTRS);
694 u8 notify_bits = FDB_NOTIFY_BIT;
695
696 if (!nest)
697 goto nla_put_failure;
698 if (test_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags))
699 notify_bits |= FDB_NOTIFY_INACTIVE_BIT;
700
701 if (nla_put_u8(skb, NFEA_ACTIVITY_NOTIFY, notify_bits)) {
702 nla_nest_cancel(skb, nest);
703 goto nla_put_failure;
704 }
705
706 nla_nest_end(skb, nest);
707 }
708
709 nlmsg_end(skb, nlh);
710 return 0;
711
712nla_put_failure:
713 nlmsg_cancel(skb, nlh);
714 return -EMSGSIZE;
715}
716
717static inline size_t fdb_nlmsg_size(void)
718{
719 return NLMSG_ALIGN(sizeof(struct ndmsg))
720 + nla_total_size(ETH_ALEN) /* NDA_LLADDR */
721 + nla_total_size(sizeof(u32)) /* NDA_MASTER */
722 + nla_total_size(sizeof(u16)) /* NDA_VLAN */
723 + nla_total_size(sizeof(struct nda_cacheinfo))
724 + nla_total_size(0) /* NDA_FDB_EXT_ATTRS */
725 + nla_total_size(sizeof(u8)); /* NFEA_ACTIVITY_NOTIFY */
726}
727
728static void fdb_notify(struct net_bridge *br,
729 const struct net_bridge_fdb_entry *fdb, int type,
730 bool swdev_notify)
731{
732 struct net *net = dev_net(br->dev);
733 struct sk_buff *skb;
734 int err = -ENOBUFS;
735
736 if (swdev_notify)
737 br_switchdev_fdb_notify(fdb, type);
738
739 skb = nlmsg_new(fdb_nlmsg_size(), GFP_ATOMIC);
740 if (skb == NULL)
741 goto errout;
742
743 err = fdb_fill_info(skb, br, fdb, 0, 0, type, 0);
744 if (err < 0) {
745 /* -EMSGSIZE implies BUG in fdb_nlmsg_size() */
746 WARN_ON(err == -EMSGSIZE);
747 kfree_skb(skb);
748 goto errout;
749 }
750 rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
751 return;
752errout:
753 rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
754}
755
756/* Dump information about entries, in response to GETNEIGH */
757int br_fdb_dump(struct sk_buff *skb,
758 struct netlink_callback *cb,
759 struct net_device *dev,
760 struct net_device *filter_dev,
761 int *idx)
762{
763 struct net_bridge *br = netdev_priv(dev);
764 struct net_bridge_fdb_entry *f;
765 int err = 0;
766
767 if (!(dev->priv_flags & IFF_EBRIDGE))
768 return err;
769
770 if (!filter_dev) {
771 err = ndo_dflt_fdb_dump(skb, cb, dev, NULL, idx);
772 if (err < 0)
773 return err;
774 }
775
776 rcu_read_lock();
777 hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
778 if (*idx < cb->args[2])
779 goto skip;
780 if (filter_dev && (!f->dst || f->dst->dev != filter_dev)) {
781 if (filter_dev != dev)
782 goto skip;
783 /* !f->dst is a special case for bridge
784 * It means the MAC belongs to the bridge
785 * Therefore need a little more filtering
786 * we only want to dump the !f->dst case
787 */
788 if (f->dst)
789 goto skip;
790 }
791 if (!filter_dev && f->dst)
792 goto skip;
793
794 err = fdb_fill_info(skb, br, f,
795 NETLINK_CB(cb->skb).portid,
796 cb->nlh->nlmsg_seq,
797 RTM_NEWNEIGH,
798 NLM_F_MULTI);
799 if (err < 0)
800 break;
801skip:
802 *idx += 1;
803 }
804 rcu_read_unlock();
805
806 return err;
807}
808
809int br_fdb_get(struct sk_buff *skb,
810 struct nlattr *tb[],
811 struct net_device *dev,
812 const unsigned char *addr,
813 u16 vid, u32 portid, u32 seq,
814 struct netlink_ext_ack *extack)
815{
816 struct net_bridge *br = netdev_priv(dev);
817 struct net_bridge_fdb_entry *f;
818 int err = 0;
819
820 rcu_read_lock();
821 f = br_fdb_find_rcu(br, addr, vid);
822 if (!f) {
823 NL_SET_ERR_MSG(extack, "Fdb entry not found");
824 err = -ENOENT;
825 goto errout;
826 }
827
828 err = fdb_fill_info(skb, br, f, portid, seq,
829 RTM_NEWNEIGH, 0);
830errout:
831 rcu_read_unlock();
832 return err;
833}
834
835/* returns true if the fdb is modified */
836static bool fdb_handle_notify(struct net_bridge_fdb_entry *fdb, u8 notify)
837{
838 bool modified = false;
839
840 /* allow to mark an entry as inactive, usually done on creation */
841 if ((notify & FDB_NOTIFY_INACTIVE_BIT) &&
842 !test_and_set_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags))
843 modified = true;
844
845 if ((notify & FDB_NOTIFY_BIT) &&
846 !test_and_set_bit(BR_FDB_NOTIFY, &fdb->flags)) {
847 /* enabled activity tracking */
848 modified = true;
849 } else if (!(notify & FDB_NOTIFY_BIT) &&
850 test_and_clear_bit(BR_FDB_NOTIFY, &fdb->flags)) {
851 /* disabled activity tracking, clear notify state */
852 clear_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags);
853 modified = true;
854 }
855
856 return modified;
857}
858
859/* Update (create or replace) forwarding database entry */
860static int fdb_add_entry(struct net_bridge *br, struct net_bridge_port *source,
861 const u8 *addr, struct ndmsg *ndm, u16 flags, u16 vid,
862 struct nlattr *nfea_tb[])
863{
864 bool is_sticky = !!(ndm->ndm_flags & NTF_STICKY);
865 bool refresh = !nfea_tb[NFEA_DONT_REFRESH];
866 struct net_bridge_fdb_entry *fdb;
867 u16 state = ndm->ndm_state;
868 bool modified = false;
869 u8 notify = 0;
870
871 /* If the port cannot learn allow only local and static entries */
872 if (source && !(state & NUD_PERMANENT) && !(state & NUD_NOARP) &&
873 !(source->state == BR_STATE_LEARNING ||
874 source->state == BR_STATE_FORWARDING))
875 return -EPERM;
876
877 if (!source && !(state & NUD_PERMANENT)) {
878 pr_info("bridge: RTM_NEWNEIGH %s without NUD_PERMANENT\n",
879 br->dev->name);
880 return -EINVAL;
881 }
882
883 if (is_sticky && (state & NUD_PERMANENT))
884 return -EINVAL;
885
886 if (nfea_tb[NFEA_ACTIVITY_NOTIFY]) {
887 notify = nla_get_u8(nfea_tb[NFEA_ACTIVITY_NOTIFY]);
888 if ((notify & ~BR_FDB_NOTIFY_SETTABLE_BITS) ||
889 (notify & BR_FDB_NOTIFY_SETTABLE_BITS) == FDB_NOTIFY_INACTIVE_BIT)
890 return -EINVAL;
891 }
892
893 fdb = br_fdb_find(br, addr, vid);
894 if (fdb == NULL) {
895 if (!(flags & NLM_F_CREATE))
896 return -ENOENT;
897
898 fdb = fdb_create(br, source, addr, vid, 0);
899 if (!fdb)
900 return -ENOMEM;
901
902 modified = true;
903 } else {
904 if (flags & NLM_F_EXCL)
905 return -EEXIST;
906
907 if (fdb->dst != source) {
908 fdb->dst = source;
909 modified = true;
910 }
911 }
912
913 if (fdb_to_nud(br, fdb) != state) {
914 if (state & NUD_PERMANENT) {
915 set_bit(BR_FDB_LOCAL, &fdb->flags);
916 if (!test_and_set_bit(BR_FDB_STATIC, &fdb->flags))
917 fdb_add_hw_addr(br, addr);
918 } else if (state & NUD_NOARP) {
919 clear_bit(BR_FDB_LOCAL, &fdb->flags);
920 if (!test_and_set_bit(BR_FDB_STATIC, &fdb->flags))
921 fdb_add_hw_addr(br, addr);
922 } else {
923 clear_bit(BR_FDB_LOCAL, &fdb->flags);
924 if (test_and_clear_bit(BR_FDB_STATIC, &fdb->flags))
925 fdb_del_hw_addr(br, addr);
926 }
927
928 modified = true;
929 }
930
931 if (is_sticky != test_bit(BR_FDB_STICKY, &fdb->flags)) {
932 change_bit(BR_FDB_STICKY, &fdb->flags);
933 modified = true;
934 }
935
936 if (fdb_handle_notify(fdb, notify))
937 modified = true;
938
939 set_bit(BR_FDB_ADDED_BY_USER, &fdb->flags);
940
941 fdb->used = jiffies;
942 if (modified) {
943 if (refresh)
944 fdb->updated = jiffies;
945 fdb_notify(br, fdb, RTM_NEWNEIGH, true);
946 }
947
948 return 0;
949}
950
951static int __br_fdb_add(struct ndmsg *ndm, struct net_bridge *br,
952 struct net_bridge_port *p, const unsigned char *addr,
953 u16 nlh_flags, u16 vid, struct nlattr *nfea_tb[])
954{
955 int err = 0;
956
957 if (ndm->ndm_flags & NTF_USE) {
958 if (!p) {
959 pr_info("bridge: RTM_NEWNEIGH %s with NTF_USE is not supported\n",
960 br->dev->name);
961 return -EINVAL;
962 }
963 if (!nbp_state_should_learn(p))
964 return 0;
965
966 local_bh_disable();
967 rcu_read_lock();
968 br_fdb_update(br, p, addr, vid, BIT(BR_FDB_ADDED_BY_USER));
969 rcu_read_unlock();
970 local_bh_enable();
971 } else if (ndm->ndm_flags & NTF_EXT_LEARNED) {
972 err = br_fdb_external_learn_add(br, p, addr, vid, true);
973 } else {
974 spin_lock_bh(&br->hash_lock);
975 err = fdb_add_entry(br, p, addr, ndm, nlh_flags, vid, nfea_tb);
976 spin_unlock_bh(&br->hash_lock);
977 }
978
979 return err;
980}
981
982static const struct nla_policy br_nda_fdb_pol[NFEA_MAX + 1] = {
983 [NFEA_ACTIVITY_NOTIFY] = { .type = NLA_U8 },
984 [NFEA_DONT_REFRESH] = { .type = NLA_FLAG },
985};
986
987/* Add new permanent fdb entry with RTM_NEWNEIGH */
988int br_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
989 struct net_device *dev,
990 const unsigned char *addr, u16 vid, u16 nlh_flags,
991 struct netlink_ext_ack *extack)
992{
993 struct nlattr *nfea_tb[NFEA_MAX + 1], *attr;
994 struct net_bridge_vlan_group *vg;
995 struct net_bridge_port *p = NULL;
996 struct net_bridge_vlan *v;
997 struct net_bridge *br = NULL;
998 int err = 0;
999
1000 trace_br_fdb_add(ndm, dev, addr, vid, nlh_flags);
1001
1002 if (!(ndm->ndm_state & (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE))) {
1003 pr_info("bridge: RTM_NEWNEIGH with invalid state %#x\n", ndm->ndm_state);
1004 return -EINVAL;
1005 }
1006
1007 if (is_zero_ether_addr(addr)) {
1008 pr_info("bridge: RTM_NEWNEIGH with invalid ether address\n");
1009 return -EINVAL;
1010 }
1011
1012 if (dev->priv_flags & IFF_EBRIDGE) {
1013 br = netdev_priv(dev);
1014 vg = br_vlan_group(br);
1015 } else {
1016 p = br_port_get_rtnl(dev);
1017 if (!p) {
1018 pr_info("bridge: RTM_NEWNEIGH %s not a bridge port\n",
1019 dev->name);
1020 return -EINVAL;
1021 }
1022 br = p->br;
1023 vg = nbp_vlan_group(p);
1024 }
1025
1026 if (tb[NDA_FDB_EXT_ATTRS]) {
1027 attr = tb[NDA_FDB_EXT_ATTRS];
1028 err = nla_parse_nested(nfea_tb, NFEA_MAX, attr,
1029 br_nda_fdb_pol, extack);
1030 if (err)
1031 return err;
1032 } else {
1033 memset(nfea_tb, 0, sizeof(struct nlattr *) * (NFEA_MAX + 1));
1034 }
1035
1036 if (vid) {
1037 v = br_vlan_find(vg, vid);
1038 if (!v || !br_vlan_should_use(v)) {
1039 pr_info("bridge: RTM_NEWNEIGH with unconfigured vlan %d on %s\n", vid, dev->name);
1040 return -EINVAL;
1041 }
1042
1043 /* VID was specified, so use it. */
1044 err = __br_fdb_add(ndm, br, p, addr, nlh_flags, vid, nfea_tb);
1045 } else {
1046 err = __br_fdb_add(ndm, br, p, addr, nlh_flags, 0, nfea_tb);
1047 if (err || !vg || !vg->num_vlans)
1048 goto out;
1049
1050 /* We have vlans configured on this port and user didn't
1051 * specify a VLAN. To be nice, add/update entry for every
1052 * vlan on this port.
1053 */
1054 list_for_each_entry(v, &vg->vlan_list, vlist) {
1055 if (!br_vlan_should_use(v))
1056 continue;
1057 err = __br_fdb_add(ndm, br, p, addr, nlh_flags, v->vid,
1058 nfea_tb);
1059 if (err)
1060 goto out;
1061 }
1062 }
1063
1064out:
1065 return err;
1066}
1067
1068static int fdb_delete_by_addr_and_port(struct net_bridge *br,
1069 const struct net_bridge_port *p,
1070 const u8 *addr, u16 vlan)
1071{
1072 struct net_bridge_fdb_entry *fdb;
1073
1074 fdb = br_fdb_find(br, addr, vlan);
1075 if (!fdb || fdb->dst != p)
1076 return -ENOENT;
1077
1078 fdb_delete(br, fdb, true);
1079
1080 return 0;
1081}
1082
1083static int __br_fdb_delete(struct net_bridge *br,
1084 const struct net_bridge_port *p,
1085 const unsigned char *addr, u16 vid)
1086{
1087 int err;
1088
1089 spin_lock_bh(&br->hash_lock);
1090 err = fdb_delete_by_addr_and_port(br, p, addr, vid);
1091 spin_unlock_bh(&br->hash_lock);
1092
1093 return err;
1094}
1095
1096/* Remove neighbor entry with RTM_DELNEIGH */
1097int br_fdb_delete(struct ndmsg *ndm, struct nlattr *tb[],
1098 struct net_device *dev,
1099 const unsigned char *addr, u16 vid)
1100{
1101 struct net_bridge_vlan_group *vg;
1102 struct net_bridge_port *p = NULL;
1103 struct net_bridge_vlan *v;
1104 struct net_bridge *br;
1105 int err;
1106
1107 if (dev->priv_flags & IFF_EBRIDGE) {
1108 br = netdev_priv(dev);
1109 vg = br_vlan_group(br);
1110 } else {
1111 p = br_port_get_rtnl(dev);
1112 if (!p) {
1113 pr_info("bridge: RTM_DELNEIGH %s not a bridge port\n",
1114 dev->name);
1115 return -EINVAL;
1116 }
1117 vg = nbp_vlan_group(p);
1118 br = p->br;
1119 }
1120
1121 if (vid) {
1122 v = br_vlan_find(vg, vid);
1123 if (!v) {
1124 pr_info("bridge: RTM_DELNEIGH with unconfigured vlan %d on %s\n", vid, dev->name);
1125 return -EINVAL;
1126 }
1127
1128 err = __br_fdb_delete(br, p, addr, vid);
1129 } else {
1130 err = -ENOENT;
1131 err &= __br_fdb_delete(br, p, addr, 0);
1132 if (!vg || !vg->num_vlans)
1133 return err;
1134
1135 list_for_each_entry(v, &vg->vlan_list, vlist) {
1136 if (!br_vlan_should_use(v))
1137 continue;
1138 err &= __br_fdb_delete(br, p, addr, v->vid);
1139 }
1140 }
1141
1142 return err;
1143}
1144
1145int br_fdb_sync_static(struct net_bridge *br, struct net_bridge_port *p)
1146{
1147 struct net_bridge_fdb_entry *f, *tmp;
1148 int err = 0;
1149
1150 ASSERT_RTNL();
1151
1152 /* the key here is that static entries change only under rtnl */
1153 rcu_read_lock();
1154 hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
1155 /* We only care for static entries */
1156 if (!test_bit(BR_FDB_STATIC, &f->flags))
1157 continue;
1158 err = dev_uc_add(p->dev, f->key.addr.addr);
1159 if (err)
1160 goto rollback;
1161 }
1162done:
1163 rcu_read_unlock();
1164
1165 return err;
1166
1167rollback:
1168 hlist_for_each_entry_rcu(tmp, &br->fdb_list, fdb_node) {
1169 /* We only care for static entries */
1170 if (!test_bit(BR_FDB_STATIC, &tmp->flags))
1171 continue;
1172 if (tmp == f)
1173 break;
1174 dev_uc_del(p->dev, tmp->key.addr.addr);
1175 }
1176
1177 goto done;
1178}
1179
1180void br_fdb_unsync_static(struct net_bridge *br, struct net_bridge_port *p)
1181{
1182 struct net_bridge_fdb_entry *f;
1183
1184 ASSERT_RTNL();
1185
1186 rcu_read_lock();
1187 hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
1188 /* We only care for static entries */
1189 if (!test_bit(BR_FDB_STATIC, &f->flags))
1190 continue;
1191
1192 dev_uc_del(p->dev, f->key.addr.addr);
1193 }
1194 rcu_read_unlock();
1195}
1196
1197int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p,
1198 const unsigned char *addr, u16 vid,
1199 bool swdev_notify)
1200{
1201 struct net_bridge_fdb_entry *fdb;
1202 bool modified = false;
1203 int err = 0;
1204
1205 trace_br_fdb_external_learn_add(br, p, addr, vid);
1206
1207 spin_lock_bh(&br->hash_lock);
1208
1209 fdb = br_fdb_find(br, addr, vid);
1210 if (!fdb) {
1211 unsigned long flags = BIT(BR_FDB_ADDED_BY_EXT_LEARN);
1212
1213 if (swdev_notify)
1214 flags |= BIT(BR_FDB_ADDED_BY_USER);
1215 fdb = fdb_create(br, p, addr, vid, flags);
1216 if (!fdb) {
1217 err = -ENOMEM;
1218 goto err_unlock;
1219 }
1220 fdb_notify(br, fdb, RTM_NEWNEIGH, swdev_notify);
1221 } else {
1222 fdb->updated = jiffies;
1223
1224 if (fdb->dst != p) {
1225 fdb->dst = p;
1226 modified = true;
1227 }
1228
1229 if (test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags)) {
1230 /* Refresh entry */
1231 fdb->used = jiffies;
1232 } else if (!test_bit(BR_FDB_ADDED_BY_USER, &fdb->flags)) {
1233 /* Take over SW learned entry */
1234 set_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags);
1235 modified = true;
1236 }
1237
1238 if (swdev_notify)
1239 set_bit(BR_FDB_ADDED_BY_USER, &fdb->flags);
1240
1241 if (modified)
1242 fdb_notify(br, fdb, RTM_NEWNEIGH, swdev_notify);
1243 }
1244
1245err_unlock:
1246 spin_unlock_bh(&br->hash_lock);
1247
1248 return err;
1249}
1250
1251int br_fdb_external_learn_del(struct net_bridge *br, struct net_bridge_port *p,
1252 const unsigned char *addr, u16 vid,
1253 bool swdev_notify)
1254{
1255 struct net_bridge_fdb_entry *fdb;
1256 int err = 0;
1257
1258 spin_lock_bh(&br->hash_lock);
1259
1260 fdb = br_fdb_find(br, addr, vid);
1261 if (fdb && test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags))
1262 fdb_delete(br, fdb, swdev_notify);
1263 else
1264 err = -ENOENT;
1265
1266 spin_unlock_bh(&br->hash_lock);
1267
1268 return err;
1269}
1270
1271void br_fdb_offloaded_set(struct net_bridge *br, struct net_bridge_port *p,
1272 const unsigned char *addr, u16 vid, bool offloaded)
1273{
1274 struct net_bridge_fdb_entry *fdb;
1275
1276 spin_lock_bh(&br->hash_lock);
1277
1278 fdb = br_fdb_find(br, addr, vid);
1279 if (fdb && offloaded != test_bit(BR_FDB_OFFLOADED, &fdb->flags))
1280 change_bit(BR_FDB_OFFLOADED, &fdb->flags);
1281
1282 spin_unlock_bh(&br->hash_lock);
1283}
1284
1285void br_fdb_clear_offload(const struct net_device *dev, u16 vid)
1286{
1287 struct net_bridge_fdb_entry *f;
1288 struct net_bridge_port *p;
1289
1290 ASSERT_RTNL();
1291
1292 p = br_port_get_rtnl(dev);
1293 if (!p)
1294 return;
1295
1296 spin_lock_bh(&p->br->hash_lock);
1297 hlist_for_each_entry(f, &p->br->fdb_list, fdb_node) {
1298 if (f->dst == p && f->key.vlan_id == vid)
1299 clear_bit(BR_FDB_OFFLOADED, &f->flags);
1300 }
1301 spin_unlock_bh(&p->br->hash_lock);
1302}
1303EXPORT_SYMBOL_GPL(br_fdb_clear_offload);