1
2#ifndef _NET_NEIGHBOUR_H
3#define _NET_NEIGHBOUR_H
4
5#include <linux/neighbour.h>
6
7
8
9
10
11
12
13
14
15
16
17
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
33
34
35
36
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)
40
41struct neighbour;
42
43enum {
44 NEIGH_VAR_MCAST_PROBES,
45 NEIGH_VAR_UCAST_PROBES,
46 NEIGH_VAR_APP_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,
53 NEIGH_VAR_PROXY_QLEN,
54 NEIGH_VAR_ANYCAST_DELAY,
55 NEIGH_VAR_PROXY_DELAY,
56 NEIGH_VAR_LOCKTIME,
57#define NEIGH_VAR_DATA_MAX (NEIGH_VAR_LOCKTIME + 1)
58
59 NEIGH_VAR_QUEUE_LEN,
60 NEIGH_VAR_RETRANS_TIME_MS,
61 NEIGH_VAR_BASE_REACHABLE_TIME_MS,
62
63 NEIGH_VAR_GC_INTERVAL,
64 NEIGH_VAR_GC_THRESH1,
65 NEIGH_VAR_GC_THRESH2,
66 NEIGH_VAR_GC_THRESH3,
67 NEIGH_VAR_MAX
68};
69
70struct neigh_parms {
71 possible_net_t net;
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;
77
78 void *sysctl_table;
79
80 int dead;
81 refcount_t refcnt;
82 struct rcu_head rcu_head;
83
84 int reachable_time;
85 int data[NEIGH_VAR_DATA_MAX];
86 DECLARE_BITMAP(data_state, NEIGH_VAR_DATA_MAX);
87};
88
89static inline void neigh_var_set(struct neigh_parms *p, int index, int val)
90{
91 set_bit(index, p->data_state);
92 p->data[index] = val;
93}
94
95#define NEIGH_VAR(p, attr) ((p)->data[NEIGH_VAR_ ## attr])
96
97
98
99
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)
102
103static inline void neigh_parms_data_state_setall(struct neigh_parms *p)
104{
105 bitmap_fill(p->data_state, NEIGH_VAR_DATA_MAX);
106}
107
108static inline void neigh_parms_data_state_cleanall(struct neigh_parms *p)
109{
110 bitmap_zero(p->data_state, NEIGH_VAR_DATA_MAX);
111}
112
113struct neigh_statistics {
114 unsigned long allocs;
115 unsigned long destroys;
116 unsigned long hash_grows;
117
118 unsigned long res_failed;
119
120 unsigned long lookups;
121 unsigned long hits;
122
123 unsigned long rcv_probes_mcast;
124 unsigned long rcv_probes_ucast;
125
126 unsigned long periodic_gc_runs;
127 unsigned long forced_gc_runs;
128
129 unsigned long unres_discards;
130 unsigned long table_fulls;
131};
132
133#define NEIGH_CACHE_STAT_INC(tbl, field) this_cpu_inc((tbl)->stats->field)
134
135struct neighbour {
136 struct neighbour __rcu *next;
137 struct neigh_table *tbl;
138 struct neigh_parms *parms;
139 unsigned long confirmed;
140 unsigned long updated;
141 rwlock_t lock;
142 refcount_t refcnt;
143 struct sk_buff_head arp_queue;
144 unsigned int arp_queue_len_bytes;
145 struct timer_list timer;
146 unsigned long used;
147 atomic_t probes;
148 __u8 flags;
149 __u8 nud_state;
150 __u8 type;
151 __u8 dead;
152 seqlock_t ha_lock;
153 unsigned char ha[ALIGN(MAX_ADDR_LEN, sizeof(unsigned long))];
154 struct hh_cache hh;
155 int (*output)(struct neighbour *, struct sk_buff *);
156 const struct neigh_ops *ops;
157 struct rcu_head rcu;
158 struct net_device *dev;
159 u8 primary_key[0];
160} __randomize_layout;
161
162struct neigh_ops {
163 int family;
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 *);
168};
169
170struct pneigh_entry {
171 struct pneigh_entry *next;
172 possible_net_t net;
173 struct net_device *dev;
174 u8 flags;
175 u8 key[0];
176};
177
178
179
180
181
182#define NEIGH_NUM_HASH_RND 4
183
184struct neigh_hash_table {
185 struct neighbour __rcu **hash_buckets;
186 unsigned int hash_shift;
187 __u32 hash_rnd[NEIGH_NUM_HASH_RND];
188 struct rcu_head rcu;
189};
190
191
192struct neigh_table {
193 int family;
194 unsigned int entry_size;
195 unsigned int key_len;
196 __be16 protocol;
197 __u32 (*hash)(const void *pkey,
198 const struct net_device *dev,
199 __u32 *hash_rnd);
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);
205 char *id;
206 struct neigh_parms parms;
207 struct list_head parms_list;
208 int gc_interval;
209 int gc_thresh1;
210 int gc_thresh2;
211 int gc_thresh3;
212 unsigned long last_flush;
213 struct delayed_work gc_work;
214 struct timer_list proxy_timer;
215 struct sk_buff_head proxy_queue;
216 atomic_t entries;
217 rwlock_t lock;
218 unsigned long last_rand;
219 struct neigh_statistics __percpu *stats;
220 struct neigh_hash_table __rcu *nht;
221 struct pneigh_entry **phash_buckets;
222};
223
224enum {
225 NEIGH_ARP_TABLE = 0,
226 NEIGH_ND_TABLE = 1,
227 NEIGH_DN_TABLE = 2,
228 NEIGH_NR_TABLES,
229 NEIGH_LINK_TABLE = NEIGH_NR_TABLES
230};
231
232static inline int neigh_parms_family(struct neigh_parms *p)
233{
234 return p->tbl->family;
235}
236
237#define NEIGH_PRIV_ALIGN sizeof(long long)
238#define NEIGH_ENTRY_SIZE(size) ALIGN((size), NEIGH_PRIV_ALIGN)
239
240static inline void *neighbour_priv(const struct neighbour *n)
241{
242 return (char *)n + n->tbl->entry_size;
243}
244
245
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_EXT_LEARNED 0x20000000
250#define NEIGH_UPDATE_F_ISROUTER 0x40000000
251#define NEIGH_UPDATE_F_ADMIN 0x80000000
252
253
254static inline bool neigh_key_eq16(const struct neighbour *n, const void *pkey)
255{
256 return *(const u16 *)n->primary_key == *(const u16 *)pkey;
257}
258
259static inline bool neigh_key_eq32(const struct neighbour *n, const void *pkey)
260{
261 return *(const u32 *)n->primary_key == *(const u32 *)pkey;
262}
263
264static inline bool neigh_key_eq128(const struct neighbour *n, const void *pkey)
265{
266 const u32 *n32 = (const u32 *)n->primary_key;
267 const u32 *p32 = pkey;
268
269 return ((n32[0] ^ p32[0]) | (n32[1] ^ p32[1]) |
270 (n32[2] ^ p32[2]) | (n32[3] ^ p32[3])) == 0;
271}
272
273static inline struct neighbour *___neigh_lookup_noref(
274 struct neigh_table *tbl,
275 bool (*key_eq)(const struct neighbour *n, const void *pkey),
276 __u32 (*hash)(const void *pkey,
277 const struct net_device *dev,
278 __u32 *hash_rnd),
279 const void *pkey,
280 struct net_device *dev)
281{
282 struct neigh_hash_table *nht = rcu_dereference_bh(tbl->nht);
283 struct neighbour *n;
284 u32 hash_val;
285
286 hash_val = hash(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
287 for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
288 n != NULL;
289 n = rcu_dereference_bh(n->next)) {
290 if (n->dev == dev && key_eq(n, pkey))
291 return n;
292 }
293
294 return NULL;
295}
296
297static inline struct neighbour *__neigh_lookup_noref(struct neigh_table *tbl,
298 const void *pkey,
299 struct net_device *dev)
300{
301 return ___neigh_lookup_noref(tbl, tbl->key_eq, tbl->hash, pkey, dev);
302}
303
304void neigh_table_init(int index, struct neigh_table *tbl);
305int neigh_table_clear(int index, struct neigh_table *tbl);
306struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
307 struct net_device *dev);
308struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net,
309 const void *pkey);
310struct neighbour *__neigh_create(struct neigh_table *tbl, const void *pkey,
311 struct net_device *dev, bool want_ref);
312static inline struct neighbour *neigh_create(struct neigh_table *tbl,
313 const void *pkey,
314 struct net_device *dev)
315{
316 return __neigh_create(tbl, pkey, dev, true);
317}
318void neigh_destroy(struct neighbour *neigh);
319int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb);
320int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new, u32 flags,
321 u32 nlmsg_pid);
322void __neigh_set_probe_once(struct neighbour *neigh);
323bool neigh_remove_one(struct neighbour *ndel, struct neigh_table *tbl);
324void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev);
325int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev);
326int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb);
327int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb);
328int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb);
329struct neighbour *neigh_event_ns(struct neigh_table *tbl,
330 u8 *lladdr, void *saddr,
331 struct net_device *dev);
332
333struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
334 struct neigh_table *tbl);
335void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms);
336
337static inline
338struct net *neigh_parms_net(const struct neigh_parms *parms)
339{
340 return read_pnet(&parms->net);
341}
342
343unsigned long neigh_rand_reach_time(unsigned long base);
344
345void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
346 struct sk_buff *skb);
347struct pneigh_entry *pneigh_lookup(struct neigh_table *tbl, struct net *net,
348 const void *key, struct net_device *dev,
349 int creat);
350struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl, struct net *net,
351 const void *key, struct net_device *dev);
352int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *key,
353 struct net_device *dev);
354
355static inline struct net *pneigh_net(const struct pneigh_entry *pneigh)
356{
357 return read_pnet(&pneigh->net);
358}
359
360void neigh_app_ns(struct neighbour *n);
361void neigh_for_each(struct neigh_table *tbl,
362 void (*cb)(struct neighbour *, void *), void *cookie);
363void __neigh_for_each_release(struct neigh_table *tbl,
364 int (*cb)(struct neighbour *));
365int neigh_xmit(int fam, struct net_device *, const void *, struct sk_buff *);
366void pneigh_for_each(struct neigh_table *tbl,
367 void (*cb)(struct pneigh_entry *));
368
369struct neigh_seq_state {
370 struct seq_net_private p;
371 struct neigh_table *tbl;
372 struct neigh_hash_table *nht;
373 void *(*neigh_sub_iter)(struct neigh_seq_state *state,
374 struct neighbour *n, loff_t *pos);
375 unsigned int bucket;
376 unsigned int flags;
377#define NEIGH_SEQ_NEIGH_ONLY 0x00000001
378#define NEIGH_SEQ_IS_PNEIGH 0x00000002
379#define NEIGH_SEQ_SKIP_NOARP 0x00000004
380};
381void *neigh_seq_start(struct seq_file *, loff_t *, struct neigh_table *,
382 unsigned int);
383void *neigh_seq_next(struct seq_file *, void *, loff_t *);
384void neigh_seq_stop(struct seq_file *, void *);
385
386int neigh_proc_dointvec(struct ctl_table *ctl, int write,
387 void __user *buffer, size_t *lenp, loff_t *ppos);
388int neigh_proc_dointvec_jiffies(struct ctl_table *ctl, int write,
389 void __user *buffer,
390 size_t *lenp, loff_t *ppos);
391int neigh_proc_dointvec_ms_jiffies(struct ctl_table *ctl, int write,
392 void __user *buffer,
393 size_t *lenp, loff_t *ppos);
394
395int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
396 proc_handler *proc_handler);
397void neigh_sysctl_unregister(struct neigh_parms *p);
398
399static inline void __neigh_parms_put(struct neigh_parms *parms)
400{
401 refcount_dec(&parms->refcnt);
402}
403
404static inline struct neigh_parms *neigh_parms_clone(struct neigh_parms *parms)
405{
406 refcount_inc(&parms->refcnt);
407 return parms;
408}
409
410
411
412
413
414static inline void neigh_release(struct neighbour *neigh)
415{
416 if (refcount_dec_and_test(&neigh->refcnt))
417 neigh_destroy(neigh);
418}
419
420static inline struct neighbour * neigh_clone(struct neighbour *neigh)
421{
422 if (neigh)
423 refcount_inc(&neigh->refcnt);
424 return neigh;
425}
426
427#define neigh_hold(n) refcount_inc(&(n)->refcnt)
428
429static inline int neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
430{
431 unsigned long now = jiffies;
432
433 if (neigh->used != now)
434 neigh->used = now;
435 if (!(neigh->nud_state&(NUD_CONNECTED|NUD_DELAY|NUD_PROBE)))
436 return __neigh_event_send(neigh, skb);
437 return 0;
438}
439
440#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
441static inline int neigh_hh_bridge(struct hh_cache *hh, struct sk_buff *skb)
442{
443 unsigned int seq, hh_alen;
444
445 do {
446 seq = read_seqbegin(&hh->hh_lock);
447 hh_alen = HH_DATA_ALIGN(ETH_HLEN);
448 memcpy(skb->data - hh_alen, hh->hh_data, ETH_ALEN + hh_alen - ETH_HLEN);
449 } while (read_seqretry(&hh->hh_lock, seq));
450 return 0;
451}
452#endif
453
454static inline int neigh_hh_output(const struct hh_cache *hh, struct sk_buff *skb)
455{
456 unsigned int seq;
457 unsigned int hh_len;
458
459 do {
460 seq = read_seqbegin(&hh->hh_lock);
461 hh_len = hh->hh_len;
462 if (likely(hh_len <= HH_DATA_MOD)) {
463
464 memcpy(skb->data - HH_DATA_MOD, hh->hh_data, HH_DATA_MOD);
465 } else {
466 unsigned int hh_alen = HH_DATA_ALIGN(hh_len);
467
468 memcpy(skb->data - hh_alen, hh->hh_data, hh_alen);
469 }
470 } while (read_seqretry(&hh->hh_lock, seq));
471
472 skb_push(skb, hh_len);
473 return dev_queue_xmit(skb);
474}
475
476static inline int neigh_output(struct neighbour *n, struct sk_buff *skb)
477{
478 const struct hh_cache *hh = &n->hh;
479
480 if ((n->nud_state & NUD_CONNECTED) && hh->hh_len)
481 return neigh_hh_output(hh, skb);
482 else
483 return n->output(n, skb);
484}
485
486static inline struct neighbour *
487__neigh_lookup(struct neigh_table *tbl, const void *pkey, struct net_device *dev, int creat)
488{
489 struct neighbour *n = neigh_lookup(tbl, pkey, dev);
490
491 if (n || !creat)
492 return n;
493
494 n = neigh_create(tbl, pkey, dev);
495 return IS_ERR(n) ? NULL : n;
496}
497
498static inline struct neighbour *
499__neigh_lookup_errno(struct neigh_table *tbl, const void *pkey,
500 struct net_device *dev)
501{
502 struct neighbour *n = neigh_lookup(tbl, pkey, dev);
503
504 if (n)
505 return n;
506
507 return neigh_create(tbl, pkey, dev);
508}
509
510struct neighbour_cb {
511 unsigned long sched_next;
512 unsigned int flags;
513};
514
515#define LOCALLY_ENQUEUED 0x1
516
517#define NEIGH_CB(skb) ((struct neighbour_cb *)(skb)->cb)
518
519static inline void neigh_ha_snapshot(char *dst, const struct neighbour *n,
520 const struct net_device *dev)
521{
522 unsigned int seq;
523
524 do {
525 seq = read_seqbegin(&n->ha_lock);
526 memcpy(dst, n->ha, dev->addr_len);
527 } while (read_seqretry(&n->ha_lock, seq));
528}
529
530static inline void neigh_update_ext_learned(struct neighbour *neigh, u32 flags,
531 int *notify)
532{
533 u8 ndm_flags = 0;
534
535 if (!(flags & NEIGH_UPDATE_F_ADMIN))
536 return;
537
538 ndm_flags |= (flags & NEIGH_UPDATE_F_EXT_LEARNED) ? NTF_EXT_LEARNED : 0;
539 if ((neigh->flags ^ ndm_flags) & NTF_EXT_LEARNED) {
540 if (ndm_flags & NTF_EXT_LEARNED)
541 neigh->flags |= NTF_EXT_LEARNED;
542 else
543 neigh->flags &= ~NTF_EXT_LEARNED;
544 *notify = 1;
545 }
546}
547#endif
548
