1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _NET_NEIGHBOUR_H
3 #define _NET_NEIGHBOUR_H
5 #include <linux/neighbour.h>
8 * Generic neighbour manipulation
11 * Pedro Roque <roque@di.fc.ul.pt>
12 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
16 * Harald Welte: <laforge@gnumonks.org>
17 * - Add neighbour cache statistics like rtstat
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>
28 #include <linux/err.h>
29 #include <linux/sysctl.h>
30 #include <linux/workqueue.h>
31 #include <net/rtnetlink.h>
34 * NUD stands for "neighbor unreachability detection"
37 #define NUD_IN_TIMER (NUD_INCOMPLETE|NUD_REACHABLE|NUD_DELAY|NUD_PROBE)
38 #define NUD_VALID (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE|NUD_PROBE|NUD_STALE|NUD_DELAY)
39 #define NUD_CONNECTED (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE)
44 NEIGH_VAR_MCAST_PROBES
,
45 NEIGH_VAR_UCAST_PROBES
,
47 NEIGH_VAR_MCAST_REPROBES
,
48 NEIGH_VAR_RETRANS_TIME
,
49 NEIGH_VAR_BASE_REACHABLE_TIME
,
50 NEIGH_VAR_DELAY_PROBE_TIME
,
51 NEIGH_VAR_GC_STALETIME
,
52 NEIGH_VAR_QUEUE_LEN_BYTES
,
54 NEIGH_VAR_ANYCAST_DELAY
,
55 NEIGH_VAR_PROXY_DELAY
,
57 #define NEIGH_VAR_DATA_MAX (NEIGH_VAR_LOCKTIME + 1)
58 /* Following are used as a second way to access one of the above */
59 NEIGH_VAR_QUEUE_LEN
, /* same data as NEIGH_VAR_QUEUE_LEN_BYTES */
60 NEIGH_VAR_RETRANS_TIME_MS
, /* same data as NEIGH_VAR_RETRANS_TIME */
61 NEIGH_VAR_BASE_REACHABLE_TIME_MS
, /* same data as NEIGH_VAR_BASE_REACHABLE_TIME */
62 /* Following are used by "default" only */
63 NEIGH_VAR_GC_INTERVAL
,
72 struct net_device
*dev
;
73 struct list_head list
;
74 int (*neigh_setup
)(struct neighbour
*);
75 void (*neigh_cleanup
)(struct neighbour
*);
76 struct neigh_table
*tbl
;
82 struct rcu_head rcu_head
;
85 int data
[NEIGH_VAR_DATA_MAX
];
86 DECLARE_BITMAP(data_state
, NEIGH_VAR_DATA_MAX
);
89 static inline void neigh_var_set(struct neigh_parms
*p
, int index
, int val
)
91 set_bit(index
, p
->data_state
);
95 #define NEIGH_VAR(p, attr) ((p)->data[NEIGH_VAR_ ## attr])
97 /* In ndo_neigh_setup, NEIGH_VAR_INIT should be used.
98 * In other cases, NEIGH_VAR_SET should be used.
100 #define NEIGH_VAR_INIT(p, attr, val) (NEIGH_VAR(p, attr) = val)
101 #define NEIGH_VAR_SET(p, attr, val) neigh_var_set(p, NEIGH_VAR_ ## attr, val)
103 static inline void neigh_parms_data_state_setall(struct neigh_parms
*p
)
105 bitmap_fill(p
->data_state
, NEIGH_VAR_DATA_MAX
);
108 static inline void neigh_parms_data_state_cleanall(struct neigh_parms
*p
)
110 bitmap_zero(p
->data_state
, NEIGH_VAR_DATA_MAX
);
113 struct neigh_statistics
{
114 unsigned long allocs
; /* number of allocated neighs */
115 unsigned long destroys
; /* number of destroyed neighs */
116 unsigned long hash_grows
; /* number of hash resizes */
118 unsigned long res_failed
; /* number of failed resolutions */
120 unsigned long lookups
; /* number of lookups */
121 unsigned long hits
; /* number of hits (among lookups) */
123 unsigned long rcv_probes_mcast
; /* number of received mcast ipv6 */
124 unsigned long rcv_probes_ucast
; /* number of received ucast ipv6 */
126 unsigned long periodic_gc_runs
; /* number of periodic GC runs */
127 unsigned long forced_gc_runs
; /* number of forced GC runs */
129 unsigned long unres_discards
; /* number of unresolved drops */
130 unsigned long table_fulls
; /* times even gc couldn't help */
133 #define NEIGH_CACHE_STAT_INC(tbl, field) this_cpu_inc((tbl)->stats->field)
136 struct neighbour __rcu
*next
;
137 struct neigh_table
*tbl
;
138 struct neigh_parms
*parms
;
139 unsigned long confirmed
;
140 unsigned long updated
;
143 struct sk_buff_head arp_queue
;
144 unsigned int arp_queue_len_bytes
;
145 struct timer_list timer
;
153 unsigned char ha
[ALIGN(MAX_ADDR_LEN
, sizeof(unsigned long))];
155 int (*output
)(struct neighbour
*, struct sk_buff
*);
156 const struct neigh_ops
*ops
;
158 struct net_device
*dev
;
160 } __randomize_layout
;
164 void (*solicit
)(struct neighbour
*, struct sk_buff
*);
165 void (*error_report
)(struct neighbour
*, struct sk_buff
*);
166 int (*output
)(struct neighbour
*, struct sk_buff
*);
167 int (*connected_output
)(struct neighbour
*, struct sk_buff
*);
170 struct pneigh_entry
{
171 struct pneigh_entry
*next
;
173 struct net_device
*dev
;
179 * neighbour table manipulation
182 #define NEIGH_NUM_HASH_RND 4
184 struct neigh_hash_table
{
185 struct neighbour __rcu
**hash_buckets
;
186 unsigned int hash_shift
;
187 __u32 hash_rnd
[NEIGH_NUM_HASH_RND
];
194 unsigned int entry_size
;
195 unsigned int key_len
;
197 __u32 (*hash
)(const void *pkey
,
198 const struct net_device
*dev
,
200 bool (*key_eq
)(const struct neighbour
*, const void *pkey
);
201 int (*constructor
)(struct neighbour
*);
202 int (*pconstructor
)(struct pneigh_entry
*);
203 void (*pdestructor
)(struct pneigh_entry
*);
204 void (*proxy_redo
)(struct sk_buff
*skb
);
206 struct neigh_parms parms
;
207 struct list_head parms_list
;
212 unsigned long last_flush
;
213 struct delayed_work gc_work
;
214 struct timer_list proxy_timer
;
215 struct sk_buff_head proxy_queue
;
218 unsigned long last_rand
;
219 struct neigh_statistics __percpu
*stats
;
220 struct neigh_hash_table __rcu
*nht
;
221 struct pneigh_entry
**phash_buckets
;
229 NEIGH_LINK_TABLE
= NEIGH_NR_TABLES
/* Pseudo table for neigh_xmit */
232 static inline int neigh_parms_family(struct neigh_parms
*p
)
234 return p
->tbl
->family
;
237 #define NEIGH_PRIV_ALIGN sizeof(long long)
238 #define NEIGH_ENTRY_SIZE(size) ALIGN((size), NEIGH_PRIV_ALIGN)
240 static inline void *neighbour_priv(const struct neighbour
*n
)
242 return (char *)n
+ n
->tbl
->entry_size
;
245 /* flags for neigh_update() */
246 #define NEIGH_UPDATE_F_OVERRIDE 0x00000001
247 #define NEIGH_UPDATE_F_WEAK_OVERRIDE 0x00000002
248 #define NEIGH_UPDATE_F_OVERRIDE_ISROUTER 0x00000004
249 #define NEIGH_UPDATE_F_ISROUTER 0x40000000
250 #define NEIGH_UPDATE_F_ADMIN 0x80000000
253 static inline bool neigh_key_eq16(const struct neighbour
*n
, const void *pkey
)
255 return *(const u16
*)n
->primary_key
== *(const u16
*)pkey
;
258 static inline bool neigh_key_eq32(const struct neighbour
*n
, const void *pkey
)
260 return *(const u32
*)n
->primary_key
== *(const u32
*)pkey
;
263 static inline bool neigh_key_eq128(const struct neighbour
*n
, const void *pkey
)
265 const u32
*n32
= (const u32
*)n
->primary_key
;
266 const u32
*p32
= pkey
;
268 return ((n32
[0] ^ p32
[0]) | (n32
[1] ^ p32
[1]) |
269 (n32
[2] ^ p32
[2]) | (n32
[3] ^ p32
[3])) == 0;
272 static inline struct neighbour
*___neigh_lookup_noref(
273 struct neigh_table
*tbl
,
274 bool (*key_eq
)(const struct neighbour
*n
, const void *pkey
),
275 __u32 (*hash
)(const void *pkey
,
276 const struct net_device
*dev
,
279 struct net_device
*dev
)
281 struct neigh_hash_table
*nht
= rcu_dereference_bh(tbl
->nht
);
285 hash_val
= hash(pkey
, dev
, nht
->hash_rnd
) >> (32 - nht
->hash_shift
);
286 for (n
= rcu_dereference_bh(nht
->hash_buckets
[hash_val
]);
288 n
= rcu_dereference_bh(n
->next
)) {
289 if (n
->dev
== dev
&& key_eq(n
, pkey
))
296 static inline struct neighbour
*__neigh_lookup_noref(struct neigh_table
*tbl
,
298 struct net_device
*dev
)
300 return ___neigh_lookup_noref(tbl
, tbl
->key_eq
, tbl
->hash
, pkey
, dev
);
303 void neigh_table_init(int index
, struct neigh_table
*tbl
);
304 int neigh_table_clear(int index
, struct neigh_table
*tbl
);
305 struct neighbour
*neigh_lookup(struct neigh_table
*tbl
, const void *pkey
,
306 struct net_device
*dev
);
307 struct neighbour
*neigh_lookup_nodev(struct neigh_table
*tbl
, struct net
*net
,
309 struct neighbour
*__neigh_create(struct neigh_table
*tbl
, const void *pkey
,
310 struct net_device
*dev
, bool want_ref
);
311 static inline struct neighbour
*neigh_create(struct neigh_table
*tbl
,
313 struct net_device
*dev
)
315 return __neigh_create(tbl
, pkey
, dev
, true);
317 void neigh_destroy(struct neighbour
*neigh
);
318 int __neigh_event_send(struct neighbour
*neigh
, struct sk_buff
*skb
);
319 int neigh_update(struct neighbour
*neigh
, const u8
*lladdr
, u8
new, u32 flags
,
321 void __neigh_set_probe_once(struct neighbour
*neigh
);
322 bool neigh_remove_one(struct neighbour
*ndel
, struct neigh_table
*tbl
);
323 void neigh_changeaddr(struct neigh_table
*tbl
, struct net_device
*dev
);
324 int neigh_ifdown(struct neigh_table
*tbl
, struct net_device
*dev
);
325 int neigh_resolve_output(struct neighbour
*neigh
, struct sk_buff
*skb
);
326 int neigh_connected_output(struct neighbour
*neigh
, struct sk_buff
*skb
);
327 int neigh_direct_output(struct neighbour
*neigh
, struct sk_buff
*skb
);
328 struct neighbour
*neigh_event_ns(struct neigh_table
*tbl
,
329 u8
*lladdr
, void *saddr
,
330 struct net_device
*dev
);
332 struct neigh_parms
*neigh_parms_alloc(struct net_device
*dev
,
333 struct neigh_table
*tbl
);
334 void neigh_parms_release(struct neigh_table
*tbl
, struct neigh_parms
*parms
);
337 struct net
*neigh_parms_net(const struct neigh_parms
*parms
)
339 return read_pnet(&parms
->net
);
342 unsigned long neigh_rand_reach_time(unsigned long base
);
344 void pneigh_enqueue(struct neigh_table
*tbl
, struct neigh_parms
*p
,
345 struct sk_buff
*skb
);
346 struct pneigh_entry
*pneigh_lookup(struct neigh_table
*tbl
, struct net
*net
,
347 const void *key
, struct net_device
*dev
,
349 struct pneigh_entry
*__pneigh_lookup(struct neigh_table
*tbl
, struct net
*net
,
350 const void *key
, struct net_device
*dev
);
351 int pneigh_delete(struct neigh_table
*tbl
, struct net
*net
, const void *key
,
352 struct net_device
*dev
);
354 static inline struct net
*pneigh_net(const struct pneigh_entry
*pneigh
)
356 return read_pnet(&pneigh
->net
);
359 void neigh_app_ns(struct neighbour
*n
);
360 void neigh_for_each(struct neigh_table
*tbl
,
361 void (*cb
)(struct neighbour
*, void *), void *cookie
);
362 void __neigh_for_each_release(struct neigh_table
*tbl
,
363 int (*cb
)(struct neighbour
*));
364 int neigh_xmit(int fam
, struct net_device
*, const void *, struct sk_buff
*);
365 void pneigh_for_each(struct neigh_table
*tbl
,
366 void (*cb
)(struct pneigh_entry
*));
368 struct neigh_seq_state
{
369 struct seq_net_private p
;
370 struct neigh_table
*tbl
;
371 struct neigh_hash_table
*nht
;
372 void *(*neigh_sub_iter
)(struct neigh_seq_state
*state
,
373 struct neighbour
*n
, loff_t
*pos
);
376 #define NEIGH_SEQ_NEIGH_ONLY 0x00000001
377 #define NEIGH_SEQ_IS_PNEIGH 0x00000002
378 #define NEIGH_SEQ_SKIP_NOARP 0x00000004
380 void *neigh_seq_start(struct seq_file
*, loff_t
*, struct neigh_table
*,
382 void *neigh_seq_next(struct seq_file
*, void *, loff_t
*);
383 void neigh_seq_stop(struct seq_file
*, void *);
385 int neigh_proc_dointvec(struct ctl_table
*ctl
, int write
,
386 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
387 int neigh_proc_dointvec_jiffies(struct ctl_table
*ctl
, int write
,
389 size_t *lenp
, loff_t
*ppos
);
390 int neigh_proc_dointvec_ms_jiffies(struct ctl_table
*ctl
, int write
,
392 size_t *lenp
, loff_t
*ppos
);
394 int neigh_sysctl_register(struct net_device
*dev
, struct neigh_parms
*p
,
395 proc_handler
*proc_handler
);
396 void neigh_sysctl_unregister(struct neigh_parms
*p
);
398 static inline void __neigh_parms_put(struct neigh_parms
*parms
)
400 refcount_dec(&parms
->refcnt
);
403 static inline struct neigh_parms
*neigh_parms_clone(struct neigh_parms
*parms
)
405 refcount_inc(&parms
->refcnt
);
410 * Neighbour references
413 static inline void neigh_release(struct neighbour
*neigh
)
415 if (refcount_dec_and_test(&neigh
->refcnt
))
416 neigh_destroy(neigh
);
419 static inline struct neighbour
* neigh_clone(struct neighbour
*neigh
)
422 refcount_inc(&neigh
->refcnt
);
426 #define neigh_hold(n) refcount_inc(&(n)->refcnt)
428 static inline int neigh_event_send(struct neighbour
*neigh
, struct sk_buff
*skb
)
430 unsigned long now
= jiffies
;
432 if (neigh
->used
!= now
)
434 if (!(neigh
->nud_state
&(NUD_CONNECTED
|NUD_DELAY
|NUD_PROBE
)))
435 return __neigh_event_send(neigh
, skb
);
439 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
440 static inline int neigh_hh_bridge(struct hh_cache
*hh
, struct sk_buff
*skb
)
442 unsigned int seq
, hh_alen
;
445 seq
= read_seqbegin(&hh
->hh_lock
);
446 hh_alen
= HH_DATA_ALIGN(ETH_HLEN
);
447 memcpy(skb
->data
- hh_alen
, hh
->hh_data
, ETH_ALEN
+ hh_alen
- ETH_HLEN
);
448 } while (read_seqretry(&hh
->hh_lock
, seq
));
453 static inline int neigh_hh_output(const struct hh_cache
*hh
, struct sk_buff
*skb
)
459 seq
= read_seqbegin(&hh
->hh_lock
);
461 if (likely(hh_len
<= HH_DATA_MOD
)) {
462 /* this is inlined by gcc */
463 memcpy(skb
->data
- HH_DATA_MOD
, hh
->hh_data
, HH_DATA_MOD
);
465 unsigned int hh_alen
= HH_DATA_ALIGN(hh_len
);
467 memcpy(skb
->data
- hh_alen
, hh
->hh_data
, hh_alen
);
469 } while (read_seqretry(&hh
->hh_lock
, seq
));
471 skb_push(skb
, hh_len
);
472 return dev_queue_xmit(skb
);
475 static inline int neigh_output(struct neighbour
*n
, struct sk_buff
*skb
)
477 const struct hh_cache
*hh
= &n
->hh
;
479 if ((n
->nud_state
& NUD_CONNECTED
) && hh
->hh_len
)
480 return neigh_hh_output(hh
, skb
);
482 return n
->output(n
, skb
);
485 static inline struct neighbour
*
486 __neigh_lookup(struct neigh_table
*tbl
, const void *pkey
, struct net_device
*dev
, int creat
)
488 struct neighbour
*n
= neigh_lookup(tbl
, pkey
, dev
);
493 n
= neigh_create(tbl
, pkey
, dev
);
494 return IS_ERR(n
) ? NULL
: n
;
497 static inline struct neighbour
*
498 __neigh_lookup_errno(struct neigh_table
*tbl
, const void *pkey
,
499 struct net_device
*dev
)
501 struct neighbour
*n
= neigh_lookup(tbl
, pkey
, dev
);
506 return neigh_create(tbl
, pkey
, dev
);
509 struct neighbour_cb
{
510 unsigned long sched_next
;
514 #define LOCALLY_ENQUEUED 0x1
516 #define NEIGH_CB(skb) ((struct neighbour_cb *)(skb)->cb)
518 static inline void neigh_ha_snapshot(char *dst
, const struct neighbour
*n
,
519 const struct net_device
*dev
)
524 seq
= read_seqbegin(&n
->ha_lock
);
525 memcpy(dst
, n
->ha
, dev
->addr_len
);
526 } while (read_seqretry(&n
->ha_lock
, seq
));