neighbour.h

  1/* SPDX-License-Identifier: GPL-2.0 */
  2#ifndef _NET_NEIGHBOUR_H
  3#define _NET_NEIGHBOUR_H
  4
  5#include <linux/neighbour.h>
  6
  7/*
  8 *	Generic neighbour manipulation
  9 *
 10 *	Authors:
 11 *	Pedro Roque		<roque@di.fc.ul.pt>
 12 *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
 13 *
 14 * 	Changes:
 15 *
 16 *	Harald Welte:		<laforge@gnumonks.org>
 17 *		- Add neighbour cache statistics like rtstat
 18 */
 19
 20#include <linux/atomic.h>
 21#include <linux/refcount.h>
 22#include <linux/netdevice.h>
 23#include <linux/skbuff.h>
 24#include <linux/rcupdate.h>
 25#include <linux/seq_file.h>
 26#include <linux/bitmap.h>
 27
 28#include <linux/err.h>
 29#include <linux/sysctl.h>
 30#include <linux/workqueue.h>
 31#include <net/rtnetlink.h>
 32#include <net/neighbour_tables.h>
 33
 34/*
 35 * NUD stands for "neighbor unreachability detection"
 36 */
 37
 38#define NUD_IN_TIMER	(NUD_INCOMPLETE|NUD_REACHABLE|NUD_DELAY|NUD_PROBE)
 39#define NUD_VALID	(NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE|NUD_PROBE|NUD_STALE|NUD_DELAY)
 40#define NUD_CONNECTED	(NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE)
 41
 42struct neighbour;
 43
 44enum {
 45	NEIGH_VAR_MCAST_PROBES,
 46	NEIGH_VAR_UCAST_PROBES,
 47	NEIGH_VAR_APP_PROBES,
 48	NEIGH_VAR_MCAST_REPROBES,
 49	NEIGH_VAR_RETRANS_TIME,
 50	NEIGH_VAR_BASE_REACHABLE_TIME,
 51	NEIGH_VAR_DELAY_PROBE_TIME,
 52	NEIGH_VAR_INTERVAL_PROBE_TIME_MS,
 53	NEIGH_VAR_GC_STALETIME,
 54	NEIGH_VAR_QUEUE_LEN_BYTES,
 55	NEIGH_VAR_PROXY_QLEN,
 56	NEIGH_VAR_ANYCAST_DELAY,
 57	NEIGH_VAR_PROXY_DELAY,
 58	NEIGH_VAR_LOCKTIME,
 59#define NEIGH_VAR_DATA_MAX (NEIGH_VAR_LOCKTIME + 1)
 60	/* Following are used as a second way to access one of the above */
 61	NEIGH_VAR_QUEUE_LEN, /* same data as NEIGH_VAR_QUEUE_LEN_BYTES */
 62	NEIGH_VAR_RETRANS_TIME_MS, /* same data as NEIGH_VAR_RETRANS_TIME */
 63	NEIGH_VAR_BASE_REACHABLE_TIME_MS, /* same data as NEIGH_VAR_BASE_REACHABLE_TIME */
 64	/* Following are used by "default" only */
 65	NEIGH_VAR_GC_INTERVAL,
 66	NEIGH_VAR_GC_THRESH1,
 67	NEIGH_VAR_GC_THRESH2,
 68	NEIGH_VAR_GC_THRESH3,
 69	NEIGH_VAR_MAX
 70};
 71
 72struct neigh_parms {
 73	possible_net_t net;
 74	struct net_device *dev;
 75	netdevice_tracker dev_tracker;
 76	struct list_head list;
 77	int	(*neigh_setup)(struct neighbour *);
 78	struct neigh_table *tbl;
 79
 80	void	*sysctl_table;
 81
 82	int dead;
 83	refcount_t refcnt;
 84	struct rcu_head rcu_head;
 85
 86	int	reachable_time;
 87	u32	qlen;
 88	int	data[NEIGH_VAR_DATA_MAX];
 89	DECLARE_BITMAP(data_state, NEIGH_VAR_DATA_MAX);
 90};
 91
 92static inline void neigh_var_set(struct neigh_parms *p, int index, int val)
 93{
 94	set_bit(index, p->data_state);
 95	WRITE_ONCE(p->data[index], val);
 96}
 97
 98#define __NEIGH_VAR(p, attr) ((p)->data[NEIGH_VAR_ ## attr])
 99#define NEIGH_VAR(p, attr) READ_ONCE(__NEIGH_VAR(p, attr))
100#define NEIGH_VAR_PTR(p, attr) (&(__NEIGH_VAR(p, attr)))
101
102/* In ndo_neigh_setup, NEIGH_VAR_INIT should be used.
103 * In other cases, NEIGH_VAR_SET should be used.
104 */
105#define NEIGH_VAR_INIT(p, attr, val) (__NEIGH_VAR(p, attr) = val)
106#define NEIGH_VAR_SET(p, attr, val) neigh_var_set(p, NEIGH_VAR_ ## attr, val)
107
108static inline void neigh_parms_data_state_setall(struct neigh_parms *p)
109{
110	bitmap_fill(p->data_state, NEIGH_VAR_DATA_MAX);
111}
112
113static inline void neigh_parms_data_state_cleanall(struct neigh_parms *p)
114{
115	bitmap_zero(p->data_state, NEIGH_VAR_DATA_MAX);
116}
117
118struct neigh_statistics {
119	unsigned long allocs;		/* number of allocated neighs */
120	unsigned long destroys;		/* number of destroyed neighs */
121	unsigned long hash_grows;	/* number of hash resizes */
122
123	unsigned long res_failed;	/* number of failed resolutions */
124
125	unsigned long lookups;		/* number of lookups */
126	unsigned long hits;		/* number of hits (among lookups) */
127
128	unsigned long rcv_probes_mcast;	/* number of received mcast ipv6 */
129	unsigned long rcv_probes_ucast; /* number of received ucast ipv6 */
130
131	unsigned long periodic_gc_runs;	/* number of periodic GC runs */
132	unsigned long forced_gc_runs;	/* number of forced GC runs */
133
134	unsigned long unres_discards;	/* number of unresolved drops */
135	unsigned long table_fulls;      /* times even gc couldn't help */
136};
137
138#define NEIGH_CACHE_STAT_INC(tbl, field) this_cpu_inc((tbl)->stats->field)
139
140struct neighbour {
141	struct hlist_node	hash;
142	struct hlist_node	dev_list;
143	struct neigh_table	*tbl;
144	struct neigh_parms	*parms;
145	unsigned long		confirmed;
146	unsigned long		updated;
147	rwlock_t		lock;
148	refcount_t		refcnt;
149	unsigned int		arp_queue_len_bytes;
150	struct sk_buff_head	arp_queue;
151	struct timer_list	timer;
152	unsigned long		used;
153	atomic_t		probes;
154	u8			nud_state;
155	u8			type;
156	u8			dead;
157	u8			protocol;
158	u32			flags;
159	seqlock_t		ha_lock;
160	unsigned char		ha[ALIGN(MAX_ADDR_LEN, sizeof(unsigned long))] __aligned(8);
161	struct hh_cache		hh;
162	int			(*output)(struct neighbour *, struct sk_buff *);
163	const struct neigh_ops	*ops;
164	struct list_head	gc_list;
165	struct list_head	managed_list;
166	struct rcu_head		rcu;
167	struct net_device	*dev;
168	netdevice_tracker	dev_tracker;
169	u8			primary_key[];
170} __randomize_layout;
171
172struct neigh_ops {
173	int			family;
174	void			(*solicit)(struct neighbour *, struct sk_buff *);
175	void			(*error_report)(struct neighbour *, struct sk_buff *);
176	int			(*output)(struct neighbour *, struct sk_buff *);
177	int			(*connected_output)(struct neighbour *, struct sk_buff *);
178};
179
180struct pneigh_entry {
181	struct pneigh_entry	__rcu *next;
182	possible_net_t		net;
183	struct net_device	*dev;
184	netdevice_tracker	dev_tracker;
185	union {
186		struct list_head	free_node;
187		struct rcu_head		rcu;
188	};
189	u32			flags;
190	u8			protocol;
191	bool			permanent;
192	u32			key[];
193};
194
195/*
196 *	neighbour table manipulation
197 */
198
199#define NEIGH_NUM_HASH_RND	4
200
201struct neigh_hash_table {
202	struct hlist_head	*hash_heads;
203	unsigned int		hash_shift;
204	__u32			hash_rnd[NEIGH_NUM_HASH_RND];
205	struct rcu_head		rcu;
206};
207
208
209struct neigh_table {
210	int			family;
211	unsigned int		entry_size;
212	unsigned int		key_len;
213	__be16			protocol;
214	__u32			(*hash)(const void *pkey,
215					const struct net_device *dev,
216					__u32 *hash_rnd);
217	bool			(*key_eq)(const struct neighbour *, const void *pkey);
218	int			(*constructor)(struct neighbour *);
219	int			(*pconstructor)(struct pneigh_entry *);
220	void			(*pdestructor)(struct pneigh_entry *);
221	void			(*proxy_redo)(struct sk_buff *skb);
222	int			(*is_multicast)(const void *pkey);
223	bool			(*allow_add)(const struct net_device *dev,
224					     struct netlink_ext_ack *extack);
225	char			*id;
226	struct neigh_parms	parms;
227	struct list_head	parms_list;
228	int			gc_interval;
229	int			gc_thresh1;
230	int			gc_thresh2;
231	int			gc_thresh3;
232	unsigned long		last_flush;
233	struct delayed_work	gc_work;
234	struct delayed_work	managed_work;
235	struct timer_list 	proxy_timer;
236	struct sk_buff_head	proxy_queue;
237	atomic_t		entries;
238	atomic_t		gc_entries;
239	struct list_head	gc_list;
240	struct list_head	managed_list;
241	spinlock_t		lock;
242	unsigned long		last_rand;
243	struct neigh_statistics	__percpu *stats;
244	struct neigh_hash_table __rcu *nht;
245	struct mutex		phash_lock;
246	struct pneigh_entry	__rcu **phash_buckets;
247};
248
249static inline int neigh_parms_family(struct neigh_parms *p)
250{
251	return p->tbl->family;
252}
253
254#define NEIGH_PRIV_ALIGN	sizeof(long long)
255#define NEIGH_ENTRY_SIZE(size)	ALIGN((size), NEIGH_PRIV_ALIGN)
256
257static inline void *neighbour_priv(const struct neighbour *n)
258{
259	return (char *)n + n->tbl->entry_size;
260}
261
262/* flags for neigh_update() */
263#define NEIGH_UPDATE_F_OVERRIDE			BIT(0)
264#define NEIGH_UPDATE_F_WEAK_OVERRIDE		BIT(1)
265#define NEIGH_UPDATE_F_OVERRIDE_ISROUTER	BIT(2)
266#define NEIGH_UPDATE_F_USE			BIT(3)
267#define NEIGH_UPDATE_F_MANAGED			BIT(4)
268#define NEIGH_UPDATE_F_EXT_LEARNED		BIT(5)
269#define NEIGH_UPDATE_F_ISROUTER			BIT(6)
270#define NEIGH_UPDATE_F_ADMIN			BIT(7)
271#define NEIGH_UPDATE_F_EXT_VALIDATED		BIT(8)
272
273/* In-kernel representation for NDA_FLAGS_EXT flags: */
274#define NTF_OLD_MASK		0xff
275#define NTF_EXT_SHIFT		8
276#define NTF_EXT_MASK		(NTF_EXT_MANAGED | NTF_EXT_EXT_VALIDATED)
277
278#define NTF_MANAGED		(NTF_EXT_MANAGED << NTF_EXT_SHIFT)
279#define NTF_EXT_VALIDATED	(NTF_EXT_EXT_VALIDATED << NTF_EXT_SHIFT)
280
281extern const struct nla_policy nda_policy[];
282
283#define neigh_for_each_in_bucket(pos, head) hlist_for_each_entry(pos, head, hash)
284#define neigh_for_each_in_bucket_rcu(pos, head) \
285	hlist_for_each_entry_rcu(pos, head, hash)
286#define neigh_for_each_in_bucket_safe(pos, tmp, head) \
287	hlist_for_each_entry_safe(pos, tmp, head, hash)
288
289static inline bool neigh_key_eq32(const struct neighbour *n, const void *pkey)
290{
291	return *(const u32 *)n->primary_key == *(const u32 *)pkey;
292}
293
294static inline bool neigh_key_eq128(const struct neighbour *n, const void *pkey)
295{
296	const u32 *n32 = (const u32 *)n->primary_key;
297	const u32 *p32 = pkey;
298
299	return ((n32[0] ^ p32[0]) | (n32[1] ^ p32[1]) |
300		(n32[2] ^ p32[2]) | (n32[3] ^ p32[3])) == 0;
301}
302
303static inline struct neighbour *___neigh_lookup_noref(
304	struct neigh_table *tbl,
305	bool (*key_eq)(const struct neighbour *n, const void *pkey),
306	__u32 (*hash)(const void *pkey,
307		      const struct net_device *dev,
308		      __u32 *hash_rnd),
309	const void *pkey,
310	struct net_device *dev)
311{
312	struct neigh_hash_table *nht = rcu_dereference(tbl->nht);
313	struct neighbour *n;
314	u32 hash_val;
315
316	hash_val = hash(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
317	neigh_for_each_in_bucket_rcu(n, &nht->hash_heads[hash_val])
318		if (n->dev == dev && key_eq(n, pkey))
319			return n;
320
321	return NULL;
322}
323
324static inline struct neighbour *__neigh_lookup_noref(struct neigh_table *tbl,
325						     const void *pkey,
326						     struct net_device *dev)
327{
328	return ___neigh_lookup_noref(tbl, tbl->key_eq, tbl->hash, pkey, dev);
329}
330
331static inline void neigh_confirm(struct neighbour *n)
332{
333	if (n) {
334		unsigned long now = jiffies;
335
336		/* avoid dirtying neighbour */
337		if (READ_ONCE(n->confirmed) != now)
338			WRITE_ONCE(n->confirmed, now);
339	}
340}
341
342void neigh_table_init(int index, struct neigh_table *tbl);
343int neigh_table_clear(int index, struct neigh_table *tbl);
344struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
345			       struct net_device *dev);
346struct neighbour *__neigh_create(struct neigh_table *tbl, const void *pkey,
347				 struct net_device *dev, bool want_ref);
348static inline struct neighbour *neigh_create(struct neigh_table *tbl,
349					     const void *pkey,
350					     struct net_device *dev)
351{
352	return __neigh_create(tbl, pkey, dev, true);
353}
354void neigh_destroy(struct neighbour *neigh);
355int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb,
356		       const bool immediate_ok);
357int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new, u32 flags,
358		 u32 nlmsg_pid);
359void __neigh_set_probe_once(struct neighbour *neigh);
360bool neigh_remove_one(struct neighbour *ndel);
361void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev);
362int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev);
363int neigh_carrier_down(struct neigh_table *tbl, struct net_device *dev);
364int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb);
365int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb);
366int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb);
367struct neighbour *neigh_event_ns(struct neigh_table *tbl,
368						u8 *lladdr, void *saddr,
369						struct net_device *dev);
370
371struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
372				      struct neigh_table *tbl);
373void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms);
374
375static inline
376struct net *neigh_parms_net(const struct neigh_parms *parms)
377{
378	return read_pnet(&parms->net);
379}
380
381unsigned long neigh_rand_reach_time(unsigned long base);
382
383static inline void neigh_set_reach_time(struct neigh_parms *p)
384{
385	unsigned long base = NEIGH_VAR(p, BASE_REACHABLE_TIME);
386
387	WRITE_ONCE(p->reachable_time, neigh_rand_reach_time(base));
388}
389
390void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
391		    struct sk_buff *skb);
392struct pneigh_entry *pneigh_lookup(struct neigh_table *tbl, struct net *net,
393				   const void *key, struct net_device *dev);
394int pneigh_create(struct neigh_table *tbl, struct net *net, const void *key,
395		  struct net_device *dev, u32 flags, u8 protocol,
396		  bool permanent);
397int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *key,
398		  struct net_device *dev);
399
400static inline struct net *pneigh_net(const struct pneigh_entry *pneigh)
401{
402	return read_pnet(&pneigh->net);
403}
404
405void neigh_app_ns(struct neighbour *n);
406void neigh_for_each(struct neigh_table *tbl,
407		    void (*cb)(struct neighbour *, void *), void *cookie);
408void __neigh_for_each_release(struct neigh_table *tbl,
409			      int (*cb)(struct neighbour *));
410int neigh_xmit(int fam, struct net_device *, const void *, struct sk_buff *);
411
412struct neigh_seq_state {
413	struct seq_net_private p;
414	struct neigh_table *tbl;
415	struct neigh_hash_table *nht;
416	void *(*neigh_sub_iter)(struct neigh_seq_state *state,
417				struct neighbour *n, loff_t *pos);
418	unsigned int bucket;
419	unsigned int flags;
420#define NEIGH_SEQ_NEIGH_ONLY	0x00000001
421#define NEIGH_SEQ_IS_PNEIGH	0x00000002
422#define NEIGH_SEQ_SKIP_NOARP	0x00000004
423};
424void *neigh_seq_start(struct seq_file *, loff_t *, struct neigh_table *,
425		      unsigned int);
426void *neigh_seq_next(struct seq_file *, void *, loff_t *);
427void neigh_seq_stop(struct seq_file *, void *);
428
429int neigh_proc_dointvec(const struct ctl_table *ctl, int write,
430			void *buffer, size_t *lenp, loff_t *ppos);
431int neigh_proc_dointvec_jiffies(const struct ctl_table *ctl, int write,
432				void *buffer,
433				size_t *lenp, loff_t *ppos);
434int neigh_proc_dointvec_ms_jiffies(const struct ctl_table *ctl, int write,
435				   void *buffer, size_t *lenp, loff_t *ppos);
436
437int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
438			  proc_handler *proc_handler);
439void neigh_sysctl_unregister(struct neigh_parms *p);
440
441static inline void __neigh_parms_put(struct neigh_parms *parms)
442{
443	refcount_dec(&parms->refcnt);
444}
445
446static inline struct neigh_parms *neigh_parms_clone(struct neigh_parms *parms)
447{
448	refcount_inc(&parms->refcnt);
449	return parms;
450}
451
452/*
453 *	Neighbour references
454 */
455
456static inline void neigh_release(struct neighbour *neigh)
457{
458	if (refcount_dec_and_test(&neigh->refcnt))
459		neigh_destroy(neigh);
460}
461
462static inline struct neighbour * neigh_clone(struct neighbour *neigh)
463{
464	if (neigh)
465		refcount_inc(&neigh->refcnt);
466	return neigh;
467}
468
469#define neigh_hold(n)	refcount_inc(&(n)->refcnt)
470
471static __always_inline int neigh_event_send_probe(struct neighbour *neigh,
472						  struct sk_buff *skb,
473						  const bool immediate_ok)
474{
475	unsigned long now = jiffies;
476
477	if (READ_ONCE(neigh->used) != now)
478		WRITE_ONCE(neigh->used, now);
479	if (!(READ_ONCE(neigh->nud_state) & (NUD_CONNECTED | NUD_DELAY | NUD_PROBE)))
480		return __neigh_event_send(neigh, skb, immediate_ok);
481	return 0;
482}
483
484static inline int neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
485{
486	return neigh_event_send_probe(neigh, skb, true);
487}
488
489#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
490static inline int neigh_hh_bridge(struct hh_cache *hh, struct sk_buff *skb)
491{
492	unsigned int seq, hh_alen;
493
494	do {
495		seq = read_seqbegin(&hh->hh_lock);
496		hh_alen = HH_DATA_ALIGN(ETH_HLEN);
497		memcpy(skb->data - hh_alen, hh->hh_data, ETH_ALEN + hh_alen - ETH_HLEN);
498	} while (read_seqretry(&hh->hh_lock, seq));
499	return 0;
500}
501#endif
502
503static inline int neigh_hh_output(const struct hh_cache *hh, struct sk_buff *skb)
504{
505	unsigned int hh_alen = 0;
506	unsigned int seq;
507	unsigned int hh_len;
508
509	do {
510		seq = read_seqbegin(&hh->hh_lock);
511		hh_len = READ_ONCE(hh->hh_len);
512		if (likely(hh_len <= HH_DATA_MOD)) {
513			hh_alen = HH_DATA_MOD;
514
515			/* skb_push() would proceed silently if we have room for
516			 * the unaligned size but not for the aligned size:
517			 * check headroom explicitly.
518			 */
519			if (likely(skb_headroom(skb) >= HH_DATA_MOD)) {
520				/* this is inlined by gcc */
521				memcpy(skb->data - HH_DATA_MOD, hh->hh_data,
522				       HH_DATA_MOD);
523			}
524		} else {
525			hh_alen = HH_DATA_ALIGN(hh_len);
526
527			if (likely(skb_headroom(skb) >= hh_alen)) {
528				memcpy(skb->data - hh_alen, hh->hh_data,
529				       hh_alen);
530			}
531		}
532	} while (read_seqretry(&hh->hh_lock, seq));
533
534	if (WARN_ON_ONCE(skb_headroom(skb) < hh_alen)) {
535		kfree_skb(skb);
536		return NET_XMIT_DROP;
537	}
538
539	__skb_push(skb, hh_len);
540	return dev_queue_xmit(skb);
541}
542
543static inline int neigh_output(struct neighbour *n, struct sk_buff *skb,
544			       bool skip_cache)
545{
546	const struct hh_cache *hh = &n->hh;
547
548	/* n->nud_state and hh->hh_len could be changed under us.
549	 * neigh_hh_output() is taking care of the race later.
550	 */
551	if (!skip_cache &&
552	    (READ_ONCE(n->nud_state) & NUD_CONNECTED) &&
553	    READ_ONCE(hh->hh_len))
554		return neigh_hh_output(hh, skb);
555
556	return READ_ONCE(n->output)(n, skb);
557}
558
559static inline struct neighbour *
560__neigh_lookup(struct neigh_table *tbl, const void *pkey, struct net_device *dev, int creat)
561{
562	struct neighbour *n = neigh_lookup(tbl, pkey, dev);
563
564	if (n || !creat)
565		return n;
566
567	n = neigh_create(tbl, pkey, dev);
568	return IS_ERR(n) ? NULL : n;
569}
570
571static inline struct neighbour *
572__neigh_lookup_errno(struct neigh_table *tbl, const void *pkey,
573  struct net_device *dev)
574{
575	struct neighbour *n = neigh_lookup(tbl, pkey, dev);
576
577	if (n)
578		return n;
579
580	return neigh_create(tbl, pkey, dev);
581}
582
583struct neighbour_cb {
584	unsigned long sched_next;
585	unsigned int flags;
586};
587
588#define LOCALLY_ENQUEUED 0x1
589
590#define NEIGH_CB(skb)	((struct neighbour_cb *)(skb)->cb)
591
592static inline void neigh_ha_snapshot(char *dst, const struct neighbour *n,
593				     const struct net_device *dev)
594{
595	unsigned int seq;
596
597	do {
598		seq = read_seqbegin(&n->ha_lock);
599		memcpy(dst, n->ha, dev->addr_len);
600	} while (read_seqretry(&n->ha_lock, seq));
601}
602
603static inline void neigh_update_is_router(struct neighbour *neigh, u32 flags,
604					  int *notify)
605{
606	u8 ndm_flags = 0;
607
608	ndm_flags |= (flags & NEIGH_UPDATE_F_ISROUTER) ? NTF_ROUTER : 0;
609	if ((neigh->flags ^ ndm_flags) & NTF_ROUTER) {
610		if (ndm_flags & NTF_ROUTER)
611			neigh->flags |= NTF_ROUTER;
612		else
613			neigh->flags &= ~NTF_ROUTER;
614		*notify = 1;
615	}
616}
617#endif