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