br_fdb.c revision 5d5eacb34c9e1fdc0a47b885d832eaa4de860dc7
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 "br_private.h"
28
29static struct kmem_cache *br_fdb_cache __read_mostly;
30static struct net_bridge_fdb_entry *fdb_find(struct hlist_head *head,
31					     const unsigned char *addr,
32					     __u16 vid);
33static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
34		      const unsigned char *addr, u16 vid);
35static void fdb_notify(struct net_bridge *br,
36		       const struct net_bridge_fdb_entry *, int);
37
38static u32 fdb_salt __read_mostly;
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	get_random_bytes(&fdb_salt, sizeof(fdb_salt));
50	return 0;
51}
52
53void br_fdb_fini(void)
54{
55	kmem_cache_destroy(br_fdb_cache);
56}
57
58
59/* if topology_changing then use forward_delay (default 15 sec)
60 * otherwise keep longer (default 5 minutes)
61 */
62static inline unsigned long hold_time(const struct net_bridge *br)
63{
64	return br->topology_change ? br->forward_delay : br->ageing_time;
65}
66
67static inline int has_expired(const struct net_bridge *br,
68				  const struct net_bridge_fdb_entry *fdb)
69{
70	return !fdb->is_static &&
71		time_before_eq(fdb->updated + hold_time(br), jiffies);
72}
73
74static inline int br_mac_hash(const unsigned char *mac, __u16 vid)
75{
76	/* use 1 byte of OUI and 3 bytes of NIC */
77	u32 key = get_unaligned((u32 *)(mac + 2));
78	return jhash_2words(key, vid, fdb_salt) & (BR_HASH_SIZE - 1);
79}
80
81static void fdb_rcu_free(struct rcu_head *head)
82{
83	struct net_bridge_fdb_entry *ent
84		= container_of(head, struct net_bridge_fdb_entry, rcu);
85	kmem_cache_free(br_fdb_cache, ent);
86}
87
88/* When a static FDB entry is added, the mac address from the entry is
89 * added to the bridge private HW address list and all required ports
90 * are then updated with the new information.
91 * Called under RTNL.
92 */
93static void fdb_add_hw(struct net_bridge *br, const unsigned char *addr)
94{
95	int err;
96	struct net_bridge_port *p;
97
98	ASSERT_RTNL();
99
100	list_for_each_entry(p, &br->port_list, list) {
101		if (!br_promisc_port(p)) {
102			err = dev_uc_add(p->dev, addr);
103			if (err)
104				goto undo;
105		}
106	}
107
108	return;
109undo:
110	list_for_each_entry_continue_reverse(p, &br->port_list, list) {
111		if (!br_promisc_port(p))
112			dev_uc_del(p->dev, addr);
113	}
114}
115
116/* When a static FDB entry is deleted, the HW address from that entry is
117 * also removed from the bridge private HW address list and updates all
118 * the ports with needed information.
119 * Called under RTNL.
120 */
121static void fdb_del_hw(struct net_bridge *br, const unsigned char *addr)
122{
123	struct net_bridge_port *p;
124
125	ASSERT_RTNL();
126
127	list_for_each_entry(p, &br->port_list, list) {
128		if (!br_promisc_port(p))
129			dev_uc_del(p->dev, addr);
130	}
131}
132
133static void fdb_delete(struct net_bridge *br, struct net_bridge_fdb_entry *f)
134{
135	if (f->is_static)
136		fdb_del_hw(br, f->addr.addr);
137
138	hlist_del_rcu(&f->hlist);
139	fdb_notify(br, f, RTM_DELNEIGH);
140	call_rcu(&f->rcu, fdb_rcu_free);
141}
142
143/* Delete a local entry if no other port had the same address. */
144static void fdb_delete_local(struct net_bridge *br,
145			     const struct net_bridge_port *p,
146			     struct net_bridge_fdb_entry *f)
147{
148	const unsigned char *addr = f->addr.addr;
149	u16 vid = f->vlan_id;
150	struct net_bridge_port *op;
151
152	/* Maybe another port has same hw addr? */
153	list_for_each_entry(op, &br->port_list, list) {
154		if (op != p && ether_addr_equal(op->dev->dev_addr, addr) &&
155		    (!vid || nbp_vlan_find(op, vid))) {
156			f->dst = op;
157			f->added_by_user = 0;
158			return;
159		}
160	}
161
162	/* Maybe bridge device has same hw addr? */
163	if (p && ether_addr_equal(br->dev->dev_addr, addr) &&
164	    (!vid || br_vlan_find(br, vid))) {
165		f->dst = NULL;
166		f->added_by_user = 0;
167		return;
168	}
169
170	fdb_delete(br, f);
171}
172
173void br_fdb_find_delete_local(struct net_bridge *br,
174			      const struct net_bridge_port *p,
175			      const unsigned char *addr, u16 vid)
176{
177	struct hlist_head *head = &br->hash[br_mac_hash(addr, vid)];
178	struct net_bridge_fdb_entry *f;
179
180	spin_lock_bh(&br->hash_lock);
181	f = fdb_find(head, addr, vid);
182	if (f && f->is_local && !f->added_by_user && f->dst == p)
183		fdb_delete_local(br, p, f);
184	spin_unlock_bh(&br->hash_lock);
185}
186
187void br_fdb_changeaddr(struct net_bridge_port *p, const unsigned char *newaddr)
188{
189	struct net_bridge *br = p->br;
190	struct net_port_vlans *pv = nbp_get_vlan_info(p);
191	bool no_vlan = !pv;
192	int i;
193	u16 vid;
194
195	spin_lock_bh(&br->hash_lock);
196
197	/* Search all chains since old address/hash is unknown */
198	for (i = 0; i < BR_HASH_SIZE; i++) {
199		struct hlist_node *h;
200		hlist_for_each(h, &br->hash[i]) {
201			struct net_bridge_fdb_entry *f;
202
203			f = hlist_entry(h, struct net_bridge_fdb_entry, hlist);
204			if (f->dst == p && f->is_local && !f->added_by_user) {
205				/* delete old one */
206				fdb_delete_local(br, p, f);
207
208				/* if this port has no vlan information
209				 * configured, we can safely be done at
210				 * this point.
211				 */
212				if (no_vlan)
213					goto insert;
214			}
215		}
216	}
217
218insert:
219	/* insert new address,  may fail if invalid address or dup. */
220	fdb_insert(br, p, newaddr, 0);
221
222	if (no_vlan)
223		goto done;
224
225	/* Now add entries for every VLAN configured on the port.
226	 * This function runs under RTNL so the bitmap will not change
227	 * from under us.
228	 */
229	for_each_set_bit(vid, pv->vlan_bitmap, VLAN_N_VID)
230		fdb_insert(br, p, newaddr, vid);
231
232done:
233	spin_unlock_bh(&br->hash_lock);
234}
235
236void br_fdb_change_mac_address(struct net_bridge *br, const u8 *newaddr)
237{
238	struct net_bridge_fdb_entry *f;
239	struct net_port_vlans *pv;
240	u16 vid = 0;
241
242	spin_lock_bh(&br->hash_lock);
243
244	/* If old entry was unassociated with any port, then delete it. */
245	f = __br_fdb_get(br, br->dev->dev_addr, 0);
246	if (f && f->is_local && !f->dst)
247		fdb_delete_local(br, NULL, f);
248
249	fdb_insert(br, NULL, newaddr, 0);
250
251	/* Now remove and add entries for every VLAN configured on the
252	 * bridge.  This function runs under RTNL so the bitmap will not
253	 * change from under us.
254	 */
255	pv = br_get_vlan_info(br);
256	if (!pv)
257		goto out;
258
259	for_each_set_bit_from(vid, pv->vlan_bitmap, VLAN_N_VID) {
260		f = __br_fdb_get(br, br->dev->dev_addr, vid);
261		if (f && f->is_local && !f->dst)
262			fdb_delete_local(br, NULL, f);
263		fdb_insert(br, NULL, newaddr, vid);
264	}
265out:
266	spin_unlock_bh(&br->hash_lock);
267}
268
269void br_fdb_cleanup(unsigned long _data)
270{
271	struct net_bridge *br = (struct net_bridge *)_data;
272	unsigned long delay = hold_time(br);
273	unsigned long next_timer = jiffies + br->ageing_time;
274	int i;
275
276	spin_lock(&br->hash_lock);
277	for (i = 0; i < BR_HASH_SIZE; i++) {
278		struct net_bridge_fdb_entry *f;
279		struct hlist_node *n;
280
281		hlist_for_each_entry_safe(f, n, &br->hash[i], hlist) {
282			unsigned long this_timer;
283			if (f->is_static)
284				continue;
285			this_timer = f->updated + delay;
286			if (time_before_eq(this_timer, jiffies))
287				fdb_delete(br, f);
288			else if (time_before(this_timer, next_timer))
289				next_timer = this_timer;
290		}
291	}
292	spin_unlock(&br->hash_lock);
293
294	mod_timer(&br->gc_timer, round_jiffies_up(next_timer));
295}
296
297/* Completely flush all dynamic entries in forwarding database.*/
298void br_fdb_flush(struct net_bridge *br)
299{
300	int i;
301
302	spin_lock_bh(&br->hash_lock);
303	for (i = 0; i < BR_HASH_SIZE; i++) {
304		struct net_bridge_fdb_entry *f;
305		struct hlist_node *n;
306		hlist_for_each_entry_safe(f, n, &br->hash[i], hlist) {
307			if (!f->is_static)
308				fdb_delete(br, f);
309		}
310	}
311	spin_unlock_bh(&br->hash_lock);
312}
313
314/* Flush all entries referring to a specific port.
315 * if do_all is set also flush static entries
316 */
317void br_fdb_delete_by_port(struct net_bridge *br,
318			   const struct net_bridge_port *p,
319			   int do_all)
320{
321	int i;
322
323	spin_lock_bh(&br->hash_lock);
324	for (i = 0; i < BR_HASH_SIZE; i++) {
325		struct hlist_node *h, *g;
326
327		hlist_for_each_safe(h, g, &br->hash[i]) {
328			struct net_bridge_fdb_entry *f
329				= hlist_entry(h, struct net_bridge_fdb_entry, hlist);
330			if (f->dst != p)
331				continue;
332
333			if (f->is_static && !do_all)
334				continue;
335
336			if (f->is_local)
337				fdb_delete_local(br, p, f);
338			else
339				fdb_delete(br, f);
340		}
341	}
342	spin_unlock_bh(&br->hash_lock);
343}
344
345/* No locking or refcounting, assumes caller has rcu_read_lock */
346struct net_bridge_fdb_entry *__br_fdb_get(struct net_bridge *br,
347					  const unsigned char *addr,
348					  __u16 vid)
349{
350	struct net_bridge_fdb_entry *fdb;
351
352	hlist_for_each_entry_rcu(fdb,
353				&br->hash[br_mac_hash(addr, vid)], hlist) {
354		if (ether_addr_equal(fdb->addr.addr, addr) &&
355		    fdb->vlan_id == vid) {
356			if (unlikely(has_expired(br, fdb)))
357				break;
358			return fdb;
359		}
360	}
361
362	return NULL;
363}
364
365#if IS_ENABLED(CONFIG_ATM_LANE)
366/* Interface used by ATM LANE hook to test
367 * if an addr is on some other bridge port */
368int br_fdb_test_addr(struct net_device *dev, unsigned char *addr)
369{
370	struct net_bridge_fdb_entry *fdb;
371	struct net_bridge_port *port;
372	int ret;
373
374	rcu_read_lock();
375	port = br_port_get_rcu(dev);
376	if (!port)
377		ret = 0;
378	else {
379		fdb = __br_fdb_get(port->br, addr, 0);
380		ret = fdb && fdb->dst && fdb->dst->dev != dev &&
381			fdb->dst->state == BR_STATE_FORWARDING;
382	}
383	rcu_read_unlock();
384
385	return ret;
386}
387#endif /* CONFIG_ATM_LANE */
388
389/*
390 * Fill buffer with forwarding table records in
391 * the API format.
392 */
393int br_fdb_fillbuf(struct net_bridge *br, void *buf,
394		   unsigned long maxnum, unsigned long skip)
395{
396	struct __fdb_entry *fe = buf;
397	int i, num = 0;
398	struct net_bridge_fdb_entry *f;
399
400	memset(buf, 0, maxnum*sizeof(struct __fdb_entry));
401
402	rcu_read_lock();
403	for (i = 0; i < BR_HASH_SIZE; i++) {
404		hlist_for_each_entry_rcu(f, &br->hash[i], hlist) {
405			if (num >= maxnum)
406				goto out;
407
408			if (has_expired(br, f))
409				continue;
410
411			/* ignore pseudo entry for local MAC address */
412			if (!f->dst)
413				continue;
414
415			if (skip) {
416				--skip;
417				continue;
418			}
419
420			/* convert from internal format to API */
421			memcpy(fe->mac_addr, f->addr.addr, ETH_ALEN);
422
423			/* due to ABI compat need to split into hi/lo */
424			fe->port_no = f->dst->port_no;
425			fe->port_hi = f->dst->port_no >> 8;
426
427			fe->is_local = f->is_local;
428			if (!f->is_static)
429				fe->ageing_timer_value = jiffies_delta_to_clock_t(jiffies - f->updated);
430			++fe;
431			++num;
432		}
433	}
434
435 out:
436	rcu_read_unlock();
437
438	return num;
439}
440
441static struct net_bridge_fdb_entry *fdb_find(struct hlist_head *head,
442					     const unsigned char *addr,
443					     __u16 vid)
444{
445	struct net_bridge_fdb_entry *fdb;
446
447	hlist_for_each_entry(fdb, head, hlist) {
448		if (ether_addr_equal(fdb->addr.addr, addr) &&
449		    fdb->vlan_id == vid)
450			return fdb;
451	}
452	return NULL;
453}
454
455static struct net_bridge_fdb_entry *fdb_find_rcu(struct hlist_head *head,
456						 const unsigned char *addr,
457						 __u16 vid)
458{
459	struct net_bridge_fdb_entry *fdb;
460
461	hlist_for_each_entry_rcu(fdb, head, hlist) {
462		if (ether_addr_equal(fdb->addr.addr, addr) &&
463		    fdb->vlan_id == vid)
464			return fdb;
465	}
466	return NULL;
467}
468
469static struct net_bridge_fdb_entry *fdb_create(struct hlist_head *head,
470					       struct net_bridge_port *source,
471					       const unsigned char *addr,
472					       __u16 vid)
473{
474	struct net_bridge_fdb_entry *fdb;
475
476	fdb = kmem_cache_alloc(br_fdb_cache, GFP_ATOMIC);
477	if (fdb) {
478		memcpy(fdb->addr.addr, addr, ETH_ALEN);
479		fdb->dst = source;
480		fdb->vlan_id = vid;
481		fdb->is_local = 0;
482		fdb->is_static = 0;
483		fdb->added_by_user = 0;
484		fdb->updated = fdb->used = jiffies;
485		hlist_add_head_rcu(&fdb->hlist, head);
486	}
487	return fdb;
488}
489
490static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
491		  const unsigned char *addr, u16 vid)
492{
493	struct hlist_head *head = &br->hash[br_mac_hash(addr, vid)];
494	struct net_bridge_fdb_entry *fdb;
495
496	if (!is_valid_ether_addr(addr))
497		return -EINVAL;
498
499	fdb = fdb_find(head, addr, vid);
500	if (fdb) {
501		/* it is okay to have multiple ports with same
502		 * address, just use the first one.
503		 */
504		if (fdb->is_local)
505			return 0;
506		br_warn(br, "adding interface %s with same address "
507		       "as a received packet\n",
508		       source ? source->dev->name : br->dev->name);
509		fdb_delete(br, fdb);
510	}
511
512	fdb = fdb_create(head, source, addr, vid);
513	if (!fdb)
514		return -ENOMEM;
515
516	fdb->is_local = fdb->is_static = 1;
517	fdb_add_hw(br, addr);
518	fdb_notify(br, fdb, RTM_NEWNEIGH);
519	return 0;
520}
521
522/* Add entry for local address of interface */
523int br_fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
524		  const unsigned char *addr, u16 vid)
525{
526	int ret;
527
528	spin_lock_bh(&br->hash_lock);
529	ret = fdb_insert(br, source, addr, vid);
530	spin_unlock_bh(&br->hash_lock);
531	return ret;
532}
533
534void br_fdb_update(struct net_bridge *br, struct net_bridge_port *source,
535		   const unsigned char *addr, u16 vid, bool added_by_user)
536{
537	struct hlist_head *head = &br->hash[br_mac_hash(addr, vid)];
538	struct net_bridge_fdb_entry *fdb;
539	bool fdb_modified = false;
540
541	/* some users want to always flood. */
542	if (hold_time(br) == 0)
543		return;
544
545	/* ignore packets unless we are using this port */
546	if (!(source->state == BR_STATE_LEARNING ||
547	      source->state == BR_STATE_FORWARDING))
548		return;
549
550	fdb = fdb_find_rcu(head, addr, vid);
551	if (likely(fdb)) {
552		/* attempt to update an entry for a local interface */
553		if (unlikely(fdb->is_local)) {
554			if (net_ratelimit())
555				br_warn(br, "received packet on %s with "
556					"own address as source address\n",
557					source->dev->name);
558		} else {
559			/* fastpath: update of existing entry */
560			if (unlikely(source != fdb->dst)) {
561				fdb->dst = source;
562				fdb_modified = true;
563			}
564			fdb->updated = jiffies;
565			if (unlikely(added_by_user))
566				fdb->added_by_user = 1;
567			if (unlikely(fdb_modified))
568				fdb_notify(br, fdb, RTM_NEWNEIGH);
569		}
570	} else {
571		spin_lock(&br->hash_lock);
572		if (likely(!fdb_find(head, addr, vid))) {
573			fdb = fdb_create(head, source, addr, vid);
574			if (fdb) {
575				if (unlikely(added_by_user))
576					fdb->added_by_user = 1;
577				fdb_notify(br, fdb, RTM_NEWNEIGH);
578			}
579		}
580		/* else  we lose race and someone else inserts
581		 * it first, don't bother updating
582		 */
583		spin_unlock(&br->hash_lock);
584	}
585}
586
587static int fdb_to_nud(const struct net_bridge_fdb_entry *fdb)
588{
589	if (fdb->is_local)
590		return NUD_PERMANENT;
591	else if (fdb->is_static)
592		return NUD_NOARP;
593	else if (has_expired(fdb->dst->br, fdb))
594		return NUD_STALE;
595	else
596		return NUD_REACHABLE;
597}
598
599static int fdb_fill_info(struct sk_buff *skb, const struct net_bridge *br,
600			 const struct net_bridge_fdb_entry *fdb,
601			 u32 portid, u32 seq, int type, unsigned int flags)
602{
603	unsigned long now = jiffies;
604	struct nda_cacheinfo ci;
605	struct nlmsghdr *nlh;
606	struct ndmsg *ndm;
607
608	nlh = nlmsg_put(skb, portid, seq, type, sizeof(*ndm), flags);
609	if (nlh == NULL)
610		return -EMSGSIZE;
611
612	ndm = nlmsg_data(nlh);
613	ndm->ndm_family	 = AF_BRIDGE;
614	ndm->ndm_pad1    = 0;
615	ndm->ndm_pad2    = 0;
616	ndm->ndm_flags	 = 0;
617	ndm->ndm_type	 = 0;
618	ndm->ndm_ifindex = fdb->dst ? fdb->dst->dev->ifindex : br->dev->ifindex;
619	ndm->ndm_state   = fdb_to_nud(fdb);
620
621	if (nla_put(skb, NDA_LLADDR, ETH_ALEN, &fdb->addr))
622		goto nla_put_failure;
623	if (nla_put_u32(skb, NDA_MASTER, br->dev->ifindex))
624		goto nla_put_failure;
625	ci.ndm_used	 = jiffies_to_clock_t(now - fdb->used);
626	ci.ndm_confirmed = 0;
627	ci.ndm_updated	 = jiffies_to_clock_t(now - fdb->updated);
628	ci.ndm_refcnt	 = 0;
629	if (nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci))
630		goto nla_put_failure;
631
632	if (nla_put(skb, NDA_VLAN, sizeof(u16), &fdb->vlan_id))
633		goto nla_put_failure;
634
635	return nlmsg_end(skb, nlh);
636
637nla_put_failure:
638	nlmsg_cancel(skb, nlh);
639	return -EMSGSIZE;
640}
641
642static inline size_t fdb_nlmsg_size(void)
643{
644	return NLMSG_ALIGN(sizeof(struct ndmsg))
645		+ nla_total_size(ETH_ALEN) /* NDA_LLADDR */
646		+ nla_total_size(sizeof(u32)) /* NDA_MASTER */
647		+ nla_total_size(sizeof(u16)) /* NDA_VLAN */
648		+ nla_total_size(sizeof(struct nda_cacheinfo));
649}
650
651static void fdb_notify(struct net_bridge *br,
652		       const struct net_bridge_fdb_entry *fdb, int type)
653{
654	struct net *net = dev_net(br->dev);
655	struct sk_buff *skb;
656	int err = -ENOBUFS;
657
658	skb = nlmsg_new(fdb_nlmsg_size(), GFP_ATOMIC);
659	if (skb == NULL)
660		goto errout;
661
662	err = fdb_fill_info(skb, br, fdb, 0, 0, type, 0);
663	if (err < 0) {
664		/* -EMSGSIZE implies BUG in fdb_nlmsg_size() */
665		WARN_ON(err == -EMSGSIZE);
666		kfree_skb(skb);
667		goto errout;
668	}
669	rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
670	return;
671errout:
672	rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
673}
674
675/* Dump information about entries, in response to GETNEIGH */
676int br_fdb_dump(struct sk_buff *skb,
677		struct netlink_callback *cb,
678		struct net_device *dev,
679		struct net_device *filter_dev,
680		int idx)
681{
682	struct net_bridge *br = netdev_priv(dev);
683	int i;
684
685	if (!(dev->priv_flags & IFF_EBRIDGE))
686		goto out;
687
688	for (i = 0; i < BR_HASH_SIZE; i++) {
689		struct net_bridge_fdb_entry *f;
690
691		hlist_for_each_entry_rcu(f, &br->hash[i], hlist) {
692			if (idx < cb->args[0])
693				goto skip;
694
695			if (filter_dev && (!f->dst || !f->dst->dev ||
696					   f->dst->dev != filter_dev))
697				goto skip;
698
699			if (fdb_fill_info(skb, br, f,
700					  NETLINK_CB(cb->skb).portid,
701					  cb->nlh->nlmsg_seq,
702					  RTM_NEWNEIGH,
703					  NLM_F_MULTI) < 0)
704				break;
705skip:
706			++idx;
707		}
708	}
709
710out:
711	return idx;
712}
713
714/* Update (create or replace) forwarding database entry */
715static int fdb_add_entry(struct net_bridge_port *source, const __u8 *addr,
716			 __u16 state, __u16 flags, __u16 vid)
717{
718	struct net_bridge *br = source->br;
719	struct hlist_head *head = &br->hash[br_mac_hash(addr, vid)];
720	struct net_bridge_fdb_entry *fdb;
721	bool modified = false;
722
723	fdb = fdb_find(head, addr, vid);
724	if (fdb == NULL) {
725		if (!(flags & NLM_F_CREATE))
726			return -ENOENT;
727
728		fdb = fdb_create(head, source, addr, vid);
729		if (!fdb)
730			return -ENOMEM;
731
732		modified = true;
733	} else {
734		if (flags & NLM_F_EXCL)
735			return -EEXIST;
736
737		if (fdb->dst != source) {
738			fdb->dst = source;
739			modified = true;
740		}
741	}
742
743	if (fdb_to_nud(fdb) != state) {
744		if (state & NUD_PERMANENT) {
745			fdb->is_local = 1;
746			if (!fdb->is_static) {
747				fdb->is_static = 1;
748				fdb_add_hw(br, addr);
749			}
750		} else if (state & NUD_NOARP) {
751			fdb->is_local = 0;
752			if (!fdb->is_static) {
753				fdb->is_static = 1;
754				fdb_add_hw(br, addr);
755			}
756		} else {
757			fdb->is_local = 0;
758			if (fdb->is_static) {
759				fdb->is_static = 0;
760				fdb_del_hw(br, addr);
761			}
762		}
763
764		modified = true;
765	}
766	fdb->added_by_user = 1;
767
768	fdb->used = jiffies;
769	if (modified) {
770		fdb->updated = jiffies;
771		fdb_notify(br, fdb, RTM_NEWNEIGH);
772	}
773
774	return 0;
775}
776
777static int __br_fdb_add(struct ndmsg *ndm, struct net_bridge_port *p,
778	       const unsigned char *addr, u16 nlh_flags, u16 vid)
779{
780	int err = 0;
781
782	if (ndm->ndm_flags & NTF_USE) {
783		rcu_read_lock();
784		br_fdb_update(p->br, p, addr, vid, true);
785		rcu_read_unlock();
786	} else {
787		spin_lock_bh(&p->br->hash_lock);
788		err = fdb_add_entry(p, addr, ndm->ndm_state,
789				    nlh_flags, vid);
790		spin_unlock_bh(&p->br->hash_lock);
791	}
792
793	return err;
794}
795
796/* Add new permanent fdb entry with RTM_NEWNEIGH */
797int br_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
798	       struct net_device *dev,
799	       const unsigned char *addr, u16 nlh_flags)
800{
801	struct net_bridge_port *p;
802	int err = 0;
803	struct net_port_vlans *pv;
804	unsigned short vid = VLAN_N_VID;
805
806	if (!(ndm->ndm_state & (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE))) {
807		pr_info("bridge: RTM_NEWNEIGH with invalid state %#x\n", ndm->ndm_state);
808		return -EINVAL;
809	}
810
811	if (tb[NDA_VLAN]) {
812		if (nla_len(tb[NDA_VLAN]) != sizeof(unsigned short)) {
813			pr_info("bridge: RTM_NEWNEIGH with invalid vlan\n");
814			return -EINVAL;
815		}
816
817		vid = nla_get_u16(tb[NDA_VLAN]);
818
819		if (!vid || vid >= VLAN_VID_MASK) {
820			pr_info("bridge: RTM_NEWNEIGH with invalid vlan id %d\n",
821				vid);
822			return -EINVAL;
823		}
824	}
825
826	if (is_zero_ether_addr(addr)) {
827		pr_info("bridge: RTM_NEWNEIGH with invalid ether address\n");
828		return -EINVAL;
829	}
830
831	p = br_port_get_rtnl(dev);
832	if (p == NULL) {
833		pr_info("bridge: RTM_NEWNEIGH %s not a bridge port\n",
834			dev->name);
835		return -EINVAL;
836	}
837
838	pv = nbp_get_vlan_info(p);
839	if (vid != VLAN_N_VID) {
840		if (!pv || !test_bit(vid, pv->vlan_bitmap)) {
841			pr_info("bridge: RTM_NEWNEIGH with unconfigured "
842				"vlan %d on port %s\n", vid, dev->name);
843			return -EINVAL;
844		}
845
846		/* VID was specified, so use it. */
847		err = __br_fdb_add(ndm, p, addr, nlh_flags, vid);
848	} else {
849		if (!pv || bitmap_empty(pv->vlan_bitmap, VLAN_N_VID)) {
850			err = __br_fdb_add(ndm, p, addr, nlh_flags, 0);
851			goto out;
852		}
853
854		/* We have vlans configured on this port and user didn't
855		 * specify a VLAN.  To be nice, add/update entry for every
856		 * vlan on this port.
857		 */
858		for_each_set_bit(vid, pv->vlan_bitmap, VLAN_N_VID) {
859			err = __br_fdb_add(ndm, p, addr, nlh_flags, vid);
860			if (err)
861				goto out;
862		}
863	}
864
865out:
866	return err;
867}
868
869static int fdb_delete_by_addr(struct net_bridge *br, const u8 *addr, u16 vlan)
870{
871	struct hlist_head *head = &br->hash[br_mac_hash(addr, vlan)];
872	struct net_bridge_fdb_entry *fdb;
873
874	fdb = fdb_find(head, addr, vlan);
875	if (!fdb)
876		return -ENOENT;
877
878	fdb_delete(br, fdb);
879	return 0;
880}
881
882static int __br_fdb_delete(struct net_bridge_port *p,
883			   const unsigned char *addr, u16 vid)
884{
885	int err;
886
887	spin_lock_bh(&p->br->hash_lock);
888	err = fdb_delete_by_addr(p->br, addr, vid);
889	spin_unlock_bh(&p->br->hash_lock);
890
891	return err;
892}
893
894/* Remove neighbor entry with RTM_DELNEIGH */
895int br_fdb_delete(struct ndmsg *ndm, struct nlattr *tb[],
896		  struct net_device *dev,
897		  const unsigned char *addr)
898{
899	struct net_bridge_port *p;
900	int err;
901	struct net_port_vlans *pv;
902	unsigned short vid = VLAN_N_VID;
903
904	if (tb[NDA_VLAN]) {
905		if (nla_len(tb[NDA_VLAN]) != sizeof(unsigned short)) {
906			pr_info("bridge: RTM_NEWNEIGH with invalid vlan\n");
907			return -EINVAL;
908		}
909
910		vid = nla_get_u16(tb[NDA_VLAN]);
911
912		if (!vid || vid >= VLAN_VID_MASK) {
913			pr_info("bridge: RTM_NEWNEIGH with invalid vlan id %d\n",
914				vid);
915			return -EINVAL;
916		}
917	}
918	p = br_port_get_rtnl(dev);
919	if (p == NULL) {
920		pr_info("bridge: RTM_DELNEIGH %s not a bridge port\n",
921			dev->name);
922		return -EINVAL;
923	}
924
925	pv = nbp_get_vlan_info(p);
926	if (vid != VLAN_N_VID) {
927		if (!pv || !test_bit(vid, pv->vlan_bitmap)) {
928			pr_info("bridge: RTM_DELNEIGH with unconfigured "
929				"vlan %d on port %s\n", vid, dev->name);
930			return -EINVAL;
931		}
932
933		err = __br_fdb_delete(p, addr, vid);
934	} else {
935		if (!pv || bitmap_empty(pv->vlan_bitmap, VLAN_N_VID)) {
936			err = __br_fdb_delete(p, addr, 0);
937			goto out;
938		}
939
940		/* We have vlans configured on this port and user didn't
941		 * specify a VLAN.  To be nice, add/update entry for every
942		 * vlan on this port.
943		 */
944		err = -ENOENT;
945		for_each_set_bit(vid, pv->vlan_bitmap, VLAN_N_VID) {
946			err &= __br_fdb_delete(p, addr, vid);
947		}
948	}
949out:
950	return err;
951}
952
953int br_fdb_sync_static(struct net_bridge *br, struct net_bridge_port *p)
954{
955	struct net_bridge_fdb_entry *fdb, *tmp;
956	int i;
957	int err;
958
959	ASSERT_RTNL();
960
961	for (i = 0; i < BR_HASH_SIZE; i++) {
962		hlist_for_each_entry(fdb, &br->hash[i], hlist) {
963			/* We only care for static entries */
964			if (!fdb->is_static)
965				continue;
966
967			err = dev_uc_add(p->dev, fdb->addr.addr);
968			if (err)
969				goto rollback;
970		}
971	}
972	return 0;
973
974rollback:
975	for (i = 0; i < BR_HASH_SIZE; i++) {
976		hlist_for_each_entry(tmp, &br->hash[i], hlist) {
977			/* If we reached the fdb that failed, we can stop */
978			if (tmp == fdb)
979				break;
980
981			/* We only care for static entries */
982			if (!tmp->is_static)
983				continue;
984
985			dev_uc_del(p->dev, tmp->addr.addr);
986		}
987	}
988	return err;
989}
990
991void br_fdb_unsync_static(struct net_bridge *br, struct net_bridge_port *p)
992{
993	struct net_bridge_fdb_entry *fdb;
994	int i;
995
996	ASSERT_RTNL();
997
998	for (i = 0; i < BR_HASH_SIZE; i++) {
999		hlist_for_each_entry_rcu(fdb, &br->hash[i], hlist) {
1000			/* We only care for static entries */
1001			if (!fdb->is_static)
1002				continue;
1003
1004			dev_uc_del(p->dev, fdb->addr.addr);
1005		}
1006	}
1007}
1008