1 #ifndef _NET_NEIGHBOUR_H
2 #define _NET_NEIGHBOUR_H
4 #include <linux/neighbour.h>
7 * Generic neighbour manipulation
10 * Pedro Roque <roque@di.fc.ul.pt>
11 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
15 * Harald Welte: <laforge@gnumonks.org>
16 * - Add neighbour cache statistics like rtstat
19 #include <linux/atomic.h>
20 #include <linux/netdevice.h>
21 #include <linux/skbuff.h>
22 #include <linux/rcupdate.h>
23 #include <linux/seq_file.h>
24 #include <linux/bitmap.h>
26 #include <linux/err.h>
27 #include <linux/sysctl.h>
28 #include <linux/workqueue.h>
29 #include <net/rtnetlink.h>
32 * NUD stands for "neighbor unreachability detection"
35 #define NUD_IN_TIMER (NUD_INCOMPLETE|NUD_REACHABLE|NUD_DELAY|NUD_PROBE)
36 #define NUD_VALID (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE|NUD_PROBE|NUD_STALE|NUD_DELAY)
37 #define NUD_CONNECTED (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE)
42 NEIGH_VAR_MCAST_PROBES,
43 NEIGH_VAR_UCAST_PROBES,
45 NEIGH_VAR_RETRANS_TIME,
46 NEIGH_VAR_BASE_REACHABLE_TIME,
47 NEIGH_VAR_DELAY_PROBE_TIME,
48 NEIGH_VAR_GC_STALETIME,
49 NEIGH_VAR_QUEUE_LEN_BYTES,
51 NEIGH_VAR_ANYCAST_DELAY,
52 NEIGH_VAR_PROXY_DELAY,
54 #define NEIGH_VAR_DATA_MAX (NEIGH_VAR_LOCKTIME + 1)
55 /* Following are used as a second way to access one of the above */
56 NEIGH_VAR_QUEUE_LEN, /* same data as NEIGH_VAR_QUEUE_LEN_BYTES */
57 NEIGH_VAR_RETRANS_TIME_MS, /* same data as NEIGH_VAR_RETRANS_TIME */
58 NEIGH_VAR_BASE_REACHABLE_TIME_MS, /* same data as NEIGH_VAR_BASE_REACHABLE_TIME */
59 /* Following are used by "default" only */
60 NEIGH_VAR_GC_INTERVAL,
71 struct net_device *dev;
72 struct list_head list;
73 int (*neigh_setup)(struct neighbour *);
74 void (*neigh_cleanup)(struct neighbour *);
75 struct neigh_table *tbl;
81 struct rcu_head rcu_head;
84 int data[NEIGH_VAR_DATA_MAX];
85 DECLARE_BITMAP(data_state, NEIGH_VAR_DATA_MAX);
88 static inline void neigh_var_set(struct neigh_parms *p, int index, int val)
90 set_bit(index, p->data_state);
94 #define NEIGH_VAR(p, attr) ((p)->data[NEIGH_VAR_ ## attr])
96 /* In ndo_neigh_setup, NEIGH_VAR_INIT should be used.
97 * In other cases, NEIGH_VAR_SET should be used.
99 #define NEIGH_VAR_INIT(p, attr, val) (NEIGH_VAR(p, attr) = val)
100 #define NEIGH_VAR_SET(p, attr, val) neigh_var_set(p, NEIGH_VAR_ ## attr, val)
102 static inline void neigh_parms_data_state_setall(struct neigh_parms *p)
104 bitmap_fill(p->data_state, NEIGH_VAR_DATA_MAX);
107 static inline void neigh_parms_data_state_cleanall(struct neigh_parms *p)
109 bitmap_zero(p->data_state, NEIGH_VAR_DATA_MAX);
112 struct neigh_statistics {
113 unsigned long allocs; /* number of allocated neighs */
114 unsigned long destroys; /* number of destroyed neighs */
115 unsigned long hash_grows; /* number of hash resizes */
117 unsigned long res_failed; /* number of failed resolutions */
119 unsigned long lookups; /* number of lookups */
120 unsigned long hits; /* number of hits (among lookups) */
122 unsigned long rcv_probes_mcast; /* number of received mcast ipv6 */
123 unsigned long rcv_probes_ucast; /* number of received ucast ipv6 */
125 unsigned long periodic_gc_runs; /* number of periodic GC runs */
126 unsigned long forced_gc_runs; /* number of forced GC runs */
128 unsigned long unres_discards; /* number of unresolved drops */
131 #define NEIGH_CACHE_STAT_INC(tbl, field) this_cpu_inc((tbl)->stats->field)
134 struct neighbour __rcu *next;
135 struct neigh_table *tbl;
136 struct neigh_parms *parms;
137 unsigned long confirmed;
138 unsigned long updated;
141 struct sk_buff_head arp_queue;
142 unsigned int arp_queue_len_bytes;
143 struct timer_list timer;
151 unsigned char ha[ALIGN(MAX_ADDR_LEN, sizeof(unsigned long))];
153 int (*output)(struct neighbour *, struct sk_buff *);
154 const struct neigh_ops *ops;
156 struct net_device *dev;
162 void (*solicit)(struct neighbour *, struct sk_buff *);
163 void (*error_report)(struct neighbour *, struct sk_buff *);
164 int (*output)(struct neighbour *, struct sk_buff *);
165 int (*connected_output)(struct neighbour *, struct sk_buff *);
168 struct pneigh_entry {
169 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];
193 struct neigh_table *next;
197 __u32 (*hash)(const void *pkey,
198 const struct net_device *dev,
200 int (*constructor)(struct neighbour *);
201 int (*pconstructor)(struct pneigh_entry *);
202 void (*pdestructor)(struct pneigh_entry *);
203 void (*proxy_redo)(struct sk_buff *skb);
205 struct neigh_parms parms;
206 struct list_head parms_list;
211 unsigned long last_flush;
212 struct delayed_work gc_work;
213 struct timer_list proxy_timer;
214 struct sk_buff_head proxy_queue;
217 unsigned long last_rand;
218 struct neigh_statistics __percpu *stats;
219 struct neigh_hash_table __rcu *nht;
220 struct pneigh_entry **phash_buckets;
230 static inline int neigh_parms_family(struct neigh_parms *p)
232 return p->tbl->family;
235 #define NEIGH_PRIV_ALIGN sizeof(long long)
236 #define NEIGH_ENTRY_SIZE(size) ALIGN((size), NEIGH_PRIV_ALIGN)
238 static inline void *neighbour_priv(const struct neighbour *n)
240 return (char *)n + n->tbl->entry_size;
243 /* flags for neigh_update() */
244 #define NEIGH_UPDATE_F_OVERRIDE 0x00000001
245 #define NEIGH_UPDATE_F_WEAK_OVERRIDE 0x00000002
246 #define NEIGH_UPDATE_F_OVERRIDE_ISROUTER 0x00000004
247 #define NEIGH_UPDATE_F_ISROUTER 0x40000000
248 #define NEIGH_UPDATE_F_ADMIN 0x80000000
250 void neigh_table_init(int index, struct neigh_table *tbl);
251 int neigh_table_clear(int index, struct neigh_table *tbl);
252 struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
253 struct net_device *dev);
254 struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net,
256 struct neighbour *__neigh_create(struct neigh_table *tbl, const void *pkey,
257 struct net_device *dev, bool want_ref);
258 static inline struct neighbour *neigh_create(struct neigh_table *tbl,
260 struct net_device *dev)
262 return __neigh_create(tbl, pkey, dev, true);
264 void neigh_destroy(struct neighbour *neigh);
265 int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb);
266 int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new, u32 flags);
267 void __neigh_set_probe_once(struct neighbour *neigh);
268 void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev);
269 int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev);
270 int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb);
271 int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb);
272 int neigh_compat_output(struct neighbour *neigh, struct sk_buff *skb);
273 int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb);
274 struct neighbour *neigh_event_ns(struct neigh_table *tbl,
275 u8 *lladdr, void *saddr,
276 struct net_device *dev);
278 struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
279 struct neigh_table *tbl);
280 void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms);
283 struct net *neigh_parms_net(const struct neigh_parms *parms)
285 return read_pnet(&parms->net);
288 unsigned long neigh_rand_reach_time(unsigned long base);
290 void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
291 struct sk_buff *skb);
292 struct pneigh_entry *pneigh_lookup(struct neigh_table *tbl, struct net *net,
293 const void *key, struct net_device *dev,
295 struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl, struct net *net,
296 const void *key, struct net_device *dev);
297 int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *key,
298 struct net_device *dev);
300 static inline struct net *pneigh_net(const struct pneigh_entry *pneigh)
302 return read_pnet(&pneigh->net);
305 void neigh_app_ns(struct neighbour *n);
306 void neigh_for_each(struct neigh_table *tbl,
307 void (*cb)(struct neighbour *, void *), void *cookie);
308 void __neigh_for_each_release(struct neigh_table *tbl,
309 int (*cb)(struct neighbour *));
310 void pneigh_for_each(struct neigh_table *tbl,
311 void (*cb)(struct pneigh_entry *));
313 struct neigh_seq_state {
314 struct seq_net_private p;
315 struct neigh_table *tbl;
316 struct neigh_hash_table *nht;
317 void *(*neigh_sub_iter)(struct neigh_seq_state *state,
318 struct neighbour *n, loff_t *pos);
321 #define NEIGH_SEQ_NEIGH_ONLY 0x00000001
322 #define NEIGH_SEQ_IS_PNEIGH 0x00000002
323 #define NEIGH_SEQ_SKIP_NOARP 0x00000004
325 void *neigh_seq_start(struct seq_file *, loff_t *, struct neigh_table *,
327 void *neigh_seq_next(struct seq_file *, void *, loff_t *);
328 void neigh_seq_stop(struct seq_file *, void *);
330 int neigh_proc_dointvec(struct ctl_table *ctl, int write,
331 void __user *buffer, size_t *lenp, loff_t *ppos);
332 int neigh_proc_dointvec_jiffies(struct ctl_table *ctl, int write,
334 size_t *lenp, loff_t *ppos);
335 int neigh_proc_dointvec_ms_jiffies(struct ctl_table *ctl, int write,
337 size_t *lenp, loff_t *ppos);
339 int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
340 proc_handler *proc_handler);
341 void neigh_sysctl_unregister(struct neigh_parms *p);
343 static inline void __neigh_parms_put(struct neigh_parms *parms)
345 atomic_dec(&parms->refcnt);
348 static inline struct neigh_parms *neigh_parms_clone(struct neigh_parms *parms)
350 atomic_inc(&parms->refcnt);
355 * Neighbour references
358 static inline void neigh_release(struct neighbour *neigh)
360 if (atomic_dec_and_test(&neigh->refcnt))
361 neigh_destroy(neigh);
364 static inline struct neighbour * neigh_clone(struct neighbour *neigh)
367 atomic_inc(&neigh->refcnt);
371 #define neigh_hold(n) atomic_inc(&(n)->refcnt)
373 static inline int neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
375 unsigned long now = jiffies;
377 if (neigh->used != now)
379 if (!(neigh->nud_state&(NUD_CONNECTED|NUD_DELAY|NUD_PROBE)))
380 return __neigh_event_send(neigh, skb);
384 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
385 static inline int neigh_hh_bridge(struct hh_cache *hh, struct sk_buff *skb)
387 unsigned int seq, hh_alen;
390 seq = read_seqbegin(&hh->hh_lock);
391 hh_alen = HH_DATA_ALIGN(ETH_HLEN);
392 memcpy(skb->data - hh_alen, hh->hh_data, ETH_ALEN + hh_alen - ETH_HLEN);
393 } while (read_seqretry(&hh->hh_lock, seq));
398 static inline int neigh_hh_output(const struct hh_cache *hh, struct sk_buff *skb)
404 seq = read_seqbegin(&hh->hh_lock);
406 if (likely(hh_len <= HH_DATA_MOD)) {
407 /* this is inlined by gcc */
408 memcpy(skb->data - HH_DATA_MOD, hh->hh_data, HH_DATA_MOD);
410 int hh_alen = HH_DATA_ALIGN(hh_len);
412 memcpy(skb->data - hh_alen, hh->hh_data, hh_alen);
414 } while (read_seqretry(&hh->hh_lock, seq));
416 skb_push(skb, hh_len);
417 return dev_queue_xmit(skb);
420 static inline struct neighbour *
421 __neigh_lookup(struct neigh_table *tbl, const void *pkey, struct net_device *dev, int creat)
423 struct neighbour *n = neigh_lookup(tbl, pkey, dev);
428 n = neigh_create(tbl, pkey, dev);
429 return IS_ERR(n) ? NULL : n;
432 static inline struct neighbour *
433 __neigh_lookup_errno(struct neigh_table *tbl, const void *pkey,
434 struct net_device *dev)
436 struct neighbour *n = neigh_lookup(tbl, pkey, dev);
441 return neigh_create(tbl, pkey, dev);
444 struct neighbour_cb {
445 unsigned long sched_next;
449 #define LOCALLY_ENQUEUED 0x1
451 #define NEIGH_CB(skb) ((struct neighbour_cb *)(skb)->cb)
453 static inline void neigh_ha_snapshot(char *dst, const struct neighbour *n,
454 const struct net_device *dev)
459 seq = read_seqbegin(&n->ha_lock);
460 memcpy(dst, n->ha, dev->addr_len);
461 } while (read_seqretry(&n->ha_lock, seq));