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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
33/*
34 * NUD stands for "neighbor unreachability detection"
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 /* 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,
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/* In ndo_neigh_setup, NEIGH_VAR_INIT should be used.
98 * In other cases, NEIGH_VAR_SET should be used.
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; /* number of allocated neighs */
115 unsigned long destroys; /* number of destroyed neighs */
116 unsigned long hash_grows; /* number of hash resizes */
117
118 unsigned long res_failed; /* number of failed resolutions */
119
120 unsigned long lookups; /* number of lookups */
121 unsigned long hits; /* number of hits (among lookups) */
122
123 unsigned long rcv_probes_mcast; /* number of received mcast ipv6 */
124 unsigned long rcv_probes_ucast; /* number of received ucast ipv6 */
125
126 unsigned long periodic_gc_runs; /* number of periodic GC runs */
127 unsigned long forced_gc_runs; /* number of forced GC runs */
128
129 unsigned long unres_discards; /* number of unresolved drops */
130 unsigned long table_fulls; /* times even gc couldn't help */
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 unsigned int arp_queue_len_bytes;
144 struct sk_buff_head arp_queue;
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 u8 protocol;
153 seqlock_t ha_lock;
154 unsigned char ha[ALIGN(MAX_ADDR_LEN, sizeof(unsigned long))] __aligned(8);
155 struct hh_cache hh;
156 int (*output)(struct neighbour *, struct sk_buff *);
157 const struct neigh_ops *ops;
158 struct list_head gc_list;
159 struct rcu_head rcu;
160 struct net_device *dev;
161 u8 primary_key[0];
162} __randomize_layout;
163
164struct neigh_ops {
165 int family;
166 void (*solicit)(struct neighbour *, struct sk_buff *);
167 void (*error_report)(struct neighbour *, struct sk_buff *);
168 int (*output)(struct neighbour *, struct sk_buff *);
169 int (*connected_output)(struct neighbour *, struct sk_buff *);
170};
171
172struct pneigh_entry {
173 struct pneigh_entry *next;
174 possible_net_t net;
175 struct net_device *dev;
176 u8 flags;
177 u8 protocol;
178 u8 key[0];
179};
180
181/*
182 * neighbour table manipulation
183 */
184
185#define NEIGH_NUM_HASH_RND 4
186
187struct neigh_hash_table {
188 struct neighbour __rcu **hash_buckets;
189 unsigned int hash_shift;
190 __u32 hash_rnd[NEIGH_NUM_HASH_RND];
191 struct rcu_head rcu;
192};
193
194
195struct neigh_table {
196 int family;
197 unsigned int entry_size;
198 unsigned int key_len;
199 __be16 protocol;
200 __u32 (*hash)(const void *pkey,
201 const struct net_device *dev,
202 __u32 *hash_rnd);
203 bool (*key_eq)(const struct neighbour *, const void *pkey);
204 int (*constructor)(struct neighbour *);
205 int (*pconstructor)(struct pneigh_entry *);
206 void (*pdestructor)(struct pneigh_entry *);
207 void (*proxy_redo)(struct sk_buff *skb);
208 bool (*allow_add)(const struct net_device *dev,
209 struct netlink_ext_ack *extack);
210 char *id;
211 struct neigh_parms parms;
212 struct list_head parms_list;
213 int gc_interval;
214 int gc_thresh1;
215 int gc_thresh2;
216 int gc_thresh3;
217 unsigned long last_flush;
218 struct delayed_work gc_work;
219 struct timer_list proxy_timer;
220 struct sk_buff_head proxy_queue;
221 atomic_t entries;
222 atomic_t gc_entries;
223 struct list_head gc_list;
224 rwlock_t lock;
225 unsigned long last_rand;
226 struct neigh_statistics __percpu *stats;
227 struct neigh_hash_table __rcu *nht;
228 struct pneigh_entry **phash_buckets;
229};
230
231enum {
232 NEIGH_ARP_TABLE = 0,
233 NEIGH_ND_TABLE = 1,
234 NEIGH_DN_TABLE = 2,
235 NEIGH_NR_TABLES,
236 NEIGH_LINK_TABLE = NEIGH_NR_TABLES /* Pseudo table for neigh_xmit */
237};
238
239static inline int neigh_parms_family(struct neigh_parms *p)
240{
241 return p->tbl->family;
242}
243
244#define NEIGH_PRIV_ALIGN sizeof(long long)
245#define NEIGH_ENTRY_SIZE(size) ALIGN((size), NEIGH_PRIV_ALIGN)
246
247static inline void *neighbour_priv(const struct neighbour *n)
248{
249 return (char *)n + n->tbl->entry_size;
250}
251
252/* flags for neigh_update() */
253#define NEIGH_UPDATE_F_OVERRIDE 0x00000001
254#define NEIGH_UPDATE_F_WEAK_OVERRIDE 0x00000002
255#define NEIGH_UPDATE_F_OVERRIDE_ISROUTER 0x00000004
256#define NEIGH_UPDATE_F_EXT_LEARNED 0x20000000
257#define NEIGH_UPDATE_F_ISROUTER 0x40000000
258#define NEIGH_UPDATE_F_ADMIN 0x80000000
259
260extern const struct nla_policy nda_policy[];
261
262static inline bool neigh_key_eq16(const struct neighbour *n, const void *pkey)
263{
264 return *(const u16 *)n->primary_key == *(const u16 *)pkey;
265}
266
267static inline bool neigh_key_eq32(const struct neighbour *n, const void *pkey)
268{
269 return *(const u32 *)n->primary_key == *(const u32 *)pkey;
270}
271
272static inline bool neigh_key_eq128(const struct neighbour *n, const void *pkey)
273{
274 const u32 *n32 = (const u32 *)n->primary_key;
275 const u32 *p32 = pkey;
276
277 return ((n32[0] ^ p32[0]) | (n32[1] ^ p32[1]) |
278 (n32[2] ^ p32[2]) | (n32[3] ^ p32[3])) == 0;
279}
280
281static inline struct neighbour *___neigh_lookup_noref(
282 struct neigh_table *tbl,
283 bool (*key_eq)(const struct neighbour *n, const void *pkey),
284 __u32 (*hash)(const void *pkey,
285 const struct net_device *dev,
286 __u32 *hash_rnd),
287 const void *pkey,
288 struct net_device *dev)
289{
290 struct neigh_hash_table *nht = rcu_dereference_bh(tbl->nht);
291 struct neighbour *n;
292 u32 hash_val;
293
294 hash_val = hash(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
295 for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
296 n != NULL;
297 n = rcu_dereference_bh(n->next)) {
298 if (n->dev == dev && key_eq(n, pkey))
299 return n;
300 }
301
302 return NULL;
303}
304
305static inline struct neighbour *__neigh_lookup_noref(struct neigh_table *tbl,
306 const void *pkey,
307 struct net_device *dev)
308{
309 return ___neigh_lookup_noref(tbl, tbl->key_eq, tbl->hash, pkey, dev);
310}
311
312void neigh_table_init(int index, struct neigh_table *tbl);
313int neigh_table_clear(int index, struct neigh_table *tbl);
314struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
315 struct net_device *dev);
316struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net,
317 const void *pkey);
318struct neighbour *__neigh_create(struct neigh_table *tbl, const void *pkey,
319 struct net_device *dev, bool want_ref);
320static inline struct neighbour *neigh_create(struct neigh_table *tbl,
321 const void *pkey,
322 struct net_device *dev)
323{
324 return __neigh_create(tbl, pkey, dev, true);
325}
326void neigh_destroy(struct neighbour *neigh);
327int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb);
328int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new, u32 flags,
329 u32 nlmsg_pid);
330void __neigh_set_probe_once(struct neighbour *neigh);
331bool neigh_remove_one(struct neighbour *ndel, struct neigh_table *tbl);
332void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev);
333int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev);
334int neigh_carrier_down(struct neigh_table *tbl, struct net_device *dev);
335int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb);
336int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb);
337int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb);
338struct neighbour *neigh_event_ns(struct neigh_table *tbl,
339 u8 *lladdr, void *saddr,
340 struct net_device *dev);
341
342struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
343 struct neigh_table *tbl);
344void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms);
345
346static inline
347struct net *neigh_parms_net(const struct neigh_parms *parms)
348{
349 return read_pnet(&parms->net);
350}
351
352unsigned long neigh_rand_reach_time(unsigned long base);
353
354void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
355 struct sk_buff *skb);
356struct pneigh_entry *pneigh_lookup(struct neigh_table *tbl, struct net *net,
357 const void *key, struct net_device *dev,
358 int creat);
359struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl, struct net *net,
360 const void *key, struct net_device *dev);
361int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *key,
362 struct net_device *dev);
363
364static inline struct net *pneigh_net(const struct pneigh_entry *pneigh)
365{
366 return read_pnet(&pneigh->net);
367}
368
369void neigh_app_ns(struct neighbour *n);
370void neigh_for_each(struct neigh_table *tbl,
371 void (*cb)(struct neighbour *, void *), void *cookie);
372void __neigh_for_each_release(struct neigh_table *tbl,
373 int (*cb)(struct neighbour *));
374int neigh_xmit(int fam, struct net_device *, const void *, struct sk_buff *);
375void pneigh_for_each(struct neigh_table *tbl,
376 void (*cb)(struct pneigh_entry *));
377
378struct neigh_seq_state {
379 struct seq_net_private p;
380 struct neigh_table *tbl;
381 struct neigh_hash_table *nht;
382 void *(*neigh_sub_iter)(struct neigh_seq_state *state,
383 struct neighbour *n, loff_t *pos);
384 unsigned int bucket;
385 unsigned int flags;
386#define NEIGH_SEQ_NEIGH_ONLY 0x00000001
387#define NEIGH_SEQ_IS_PNEIGH 0x00000002
388#define NEIGH_SEQ_SKIP_NOARP 0x00000004
389};
390void *neigh_seq_start(struct seq_file *, loff_t *, struct neigh_table *,
391 unsigned int);
392void *neigh_seq_next(struct seq_file *, void *, loff_t *);
393void neigh_seq_stop(struct seq_file *, void *);
394
395int neigh_proc_dointvec(struct ctl_table *ctl, int write,
396 void __user *buffer, size_t *lenp, loff_t *ppos);
397int neigh_proc_dointvec_jiffies(struct ctl_table *ctl, int write,
398 void __user *buffer,
399 size_t *lenp, loff_t *ppos);
400int neigh_proc_dointvec_ms_jiffies(struct ctl_table *ctl, int write,
401 void __user *buffer,
402 size_t *lenp, loff_t *ppos);
403
404int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
405 proc_handler *proc_handler);
406void neigh_sysctl_unregister(struct neigh_parms *p);
407
408static inline void __neigh_parms_put(struct neigh_parms *parms)
409{
410 refcount_dec(&parms->refcnt);
411}
412
413static inline struct neigh_parms *neigh_parms_clone(struct neigh_parms *parms)
414{
415 refcount_inc(&parms->refcnt);
416 return parms;
417}
418
419/*
420 * Neighbour references
421 */
422
423static inline void neigh_release(struct neighbour *neigh)
424{
425 if (refcount_dec_and_test(&neigh->refcnt))
426 neigh_destroy(neigh);
427}
428
429static inline struct neighbour * neigh_clone(struct neighbour *neigh)
430{
431 if (neigh)
432 refcount_inc(&neigh->refcnt);
433 return neigh;
434}
435
436#define neigh_hold(n) refcount_inc(&(n)->refcnt)
437
438static inline int neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
439{
440 unsigned long now = jiffies;
441
442 if (READ_ONCE(neigh->used) != now)
443 WRITE_ONCE(neigh->used, now);
444 if (!(neigh->nud_state&(NUD_CONNECTED|NUD_DELAY|NUD_PROBE)))
445 return __neigh_event_send(neigh, skb);
446 return 0;
447}
448
449#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
450static inline int neigh_hh_bridge(struct hh_cache *hh, struct sk_buff *skb)
451{
452 unsigned int seq, hh_alen;
453
454 do {
455 seq = read_seqbegin(&hh->hh_lock);
456 hh_alen = HH_DATA_ALIGN(ETH_HLEN);
457 memcpy(skb->data - hh_alen, hh->hh_data, ETH_ALEN + hh_alen - ETH_HLEN);
458 } while (read_seqretry(&hh->hh_lock, seq));
459 return 0;
460}
461#endif
462
463static inline int neigh_hh_output(const struct hh_cache *hh, struct sk_buff *skb)
464{
465 unsigned int hh_alen = 0;
466 unsigned int seq;
467 unsigned int hh_len;
468
469 do {
470 seq = read_seqbegin(&hh->hh_lock);
471 hh_len = hh->hh_len;
472 if (likely(hh_len <= HH_DATA_MOD)) {
473 hh_alen = HH_DATA_MOD;
474
475 /* skb_push() would proceed silently if we have room for
476 * the unaligned size but not for the aligned size:
477 * check headroom explicitly.
478 */
479 if (likely(skb_headroom(skb) >= HH_DATA_MOD)) {
480 /* this is inlined by gcc */
481 memcpy(skb->data - HH_DATA_MOD, hh->hh_data,
482 HH_DATA_MOD);
483 }
484 } else {
485 hh_alen = HH_DATA_ALIGN(hh_len);
486
487 if (likely(skb_headroom(skb) >= hh_alen)) {
488 memcpy(skb->data - hh_alen, hh->hh_data,
489 hh_alen);
490 }
491 }
492 } while (read_seqretry(&hh->hh_lock, seq));
493
494 if (WARN_ON_ONCE(skb_headroom(skb) < hh_alen)) {
495 kfree_skb(skb);
496 return NET_XMIT_DROP;
497 }
498
499 __skb_push(skb, hh_len);
500 return dev_queue_xmit(skb);
501}
502
503static inline int neigh_output(struct neighbour *n, struct sk_buff *skb,
504 bool skip_cache)
505{
506 const struct hh_cache *hh = &n->hh;
507
508 if ((n->nud_state & NUD_CONNECTED) && hh->hh_len && !skip_cache)
509 return neigh_hh_output(hh, skb);
510 else
511 return n->output(n, skb);
512}
513
514static inline struct neighbour *
515__neigh_lookup(struct neigh_table *tbl, const void *pkey, struct net_device *dev, int creat)
516{
517 struct neighbour *n = neigh_lookup(tbl, pkey, dev);
518
519 if (n || !creat)
520 return n;
521
522 n = neigh_create(tbl, pkey, dev);
523 return IS_ERR(n) ? NULL : n;
524}
525
526static inline struct neighbour *
527__neigh_lookup_errno(struct neigh_table *tbl, const void *pkey,
528 struct net_device *dev)
529{
530 struct neighbour *n = neigh_lookup(tbl, pkey, dev);
531
532 if (n)
533 return n;
534
535 return neigh_create(tbl, pkey, dev);
536}
537
538struct neighbour_cb {
539 unsigned long sched_next;
540 unsigned int flags;
541};
542
543#define LOCALLY_ENQUEUED 0x1
544
545#define NEIGH_CB(skb) ((struct neighbour_cb *)(skb)->cb)
546
547static inline void neigh_ha_snapshot(char *dst, const struct neighbour *n,
548 const struct net_device *dev)
549{
550 unsigned int seq;
551
552 do {
553 seq = read_seqbegin(&n->ha_lock);
554 memcpy(dst, n->ha, dev->addr_len);
555 } while (read_seqretry(&n->ha_lock, seq));
556}
557
558static inline void neigh_update_is_router(struct neighbour *neigh, u32 flags,
559 int *notify)
560{
561 u8 ndm_flags = 0;
562
563 ndm_flags |= (flags & NEIGH_UPDATE_F_ISROUTER) ? NTF_ROUTER : 0;
564 if ((neigh->flags ^ ndm_flags) & NTF_ROUTER) {
565 if (ndm_flags & NTF_ROUTER)
566 neigh->flags |= NTF_ROUTER;
567 else
568 neigh->flags &= ~NTF_ROUTER;
569 *notify = 1;
570 }
571}
572#endif
1#ifndef _NET_NEIGHBOUR_H
2#define _NET_NEIGHBOUR_H
3
4#include <linux/neighbour.h>
5
6/*
7 * Generic neighbour manipulation
8 *
9 * Authors:
10 * Pedro Roque <roque@di.fc.ul.pt>
11 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
12 *
13 * Changes:
14 *
15 * Harald Welte: <laforge@gnumonks.org>
16 * - Add neighbour cache statistics like rtstat
17 */
18
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>
25
26#include <linux/err.h>
27#include <linux/sysctl.h>
28#include <linux/workqueue.h>
29#include <net/rtnetlink.h>
30
31/*
32 * NUD stands for "neighbor unreachability detection"
33 */
34
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)
38
39struct neighbour;
40
41enum {
42 NEIGH_VAR_MCAST_PROBES,
43 NEIGH_VAR_UCAST_PROBES,
44 NEIGH_VAR_APP_PROBES,
45 NEIGH_VAR_MCAST_REPROBES,
46 NEIGH_VAR_RETRANS_TIME,
47 NEIGH_VAR_BASE_REACHABLE_TIME,
48 NEIGH_VAR_DELAY_PROBE_TIME,
49 NEIGH_VAR_GC_STALETIME,
50 NEIGH_VAR_QUEUE_LEN_BYTES,
51 NEIGH_VAR_PROXY_QLEN,
52 NEIGH_VAR_ANYCAST_DELAY,
53 NEIGH_VAR_PROXY_DELAY,
54 NEIGH_VAR_LOCKTIME,
55#define NEIGH_VAR_DATA_MAX (NEIGH_VAR_LOCKTIME + 1)
56 /* Following are used as a second way to access one of the above */
57 NEIGH_VAR_QUEUE_LEN, /* same data as NEIGH_VAR_QUEUE_LEN_BYTES */
58 NEIGH_VAR_RETRANS_TIME_MS, /* same data as NEIGH_VAR_RETRANS_TIME */
59 NEIGH_VAR_BASE_REACHABLE_TIME_MS, /* same data as NEIGH_VAR_BASE_REACHABLE_TIME */
60 /* Following are used by "default" only */
61 NEIGH_VAR_GC_INTERVAL,
62 NEIGH_VAR_GC_THRESH1,
63 NEIGH_VAR_GC_THRESH2,
64 NEIGH_VAR_GC_THRESH3,
65 NEIGH_VAR_MAX
66};
67
68struct neigh_parms {
69 possible_net_t net;
70 struct net_device *dev;
71 struct list_head list;
72 int (*neigh_setup)(struct neighbour *);
73 void (*neigh_cleanup)(struct neighbour *);
74 struct neigh_table *tbl;
75
76 void *sysctl_table;
77
78 int dead;
79 atomic_t refcnt;
80 struct rcu_head rcu_head;
81
82 int reachable_time;
83 int data[NEIGH_VAR_DATA_MAX];
84 DECLARE_BITMAP(data_state, NEIGH_VAR_DATA_MAX);
85};
86
87static inline void neigh_var_set(struct neigh_parms *p, int index, int val)
88{
89 set_bit(index, p->data_state);
90 p->data[index] = val;
91}
92
93#define NEIGH_VAR(p, attr) ((p)->data[NEIGH_VAR_ ## attr])
94
95/* In ndo_neigh_setup, NEIGH_VAR_INIT should be used.
96 * In other cases, NEIGH_VAR_SET should be used.
97 */
98#define NEIGH_VAR_INIT(p, attr, val) (NEIGH_VAR(p, attr) = val)
99#define NEIGH_VAR_SET(p, attr, val) neigh_var_set(p, NEIGH_VAR_ ## attr, val)
100
101static inline void neigh_parms_data_state_setall(struct neigh_parms *p)
102{
103 bitmap_fill(p->data_state, NEIGH_VAR_DATA_MAX);
104}
105
106static inline void neigh_parms_data_state_cleanall(struct neigh_parms *p)
107{
108 bitmap_zero(p->data_state, NEIGH_VAR_DATA_MAX);
109}
110
111struct neigh_statistics {
112 unsigned long allocs; /* number of allocated neighs */
113 unsigned long destroys; /* number of destroyed neighs */
114 unsigned long hash_grows; /* number of hash resizes */
115
116 unsigned long res_failed; /* number of failed resolutions */
117
118 unsigned long lookups; /* number of lookups */
119 unsigned long hits; /* number of hits (among lookups) */
120
121 unsigned long rcv_probes_mcast; /* number of received mcast ipv6 */
122 unsigned long rcv_probes_ucast; /* number of received ucast ipv6 */
123
124 unsigned long periodic_gc_runs; /* number of periodic GC runs */
125 unsigned long forced_gc_runs; /* number of forced GC runs */
126
127 unsigned long unres_discards; /* number of unresolved drops */
128 unsigned long table_fulls; /* times even gc couldn't help */
129};
130
131#define NEIGH_CACHE_STAT_INC(tbl, field) this_cpu_inc((tbl)->stats->field)
132
133struct neighbour {
134 struct neighbour __rcu *next;
135 struct neigh_table *tbl;
136 struct neigh_parms *parms;
137 unsigned long confirmed;
138 unsigned long updated;
139 rwlock_t lock;
140 atomic_t refcnt;
141 struct sk_buff_head arp_queue;
142 unsigned int arp_queue_len_bytes;
143 struct timer_list timer;
144 unsigned long used;
145 atomic_t probes;
146 __u8 flags;
147 __u8 nud_state;
148 __u8 type;
149 __u8 dead;
150 seqlock_t ha_lock;
151 unsigned char ha[ALIGN(MAX_ADDR_LEN, sizeof(unsigned long))];
152 struct hh_cache hh;
153 int (*output)(struct neighbour *, struct sk_buff *);
154 const struct neigh_ops *ops;
155 struct rcu_head rcu;
156 struct net_device *dev;
157 u8 primary_key[0];
158};
159
160struct neigh_ops {
161 int family;
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 *);
166};
167
168struct pneigh_entry {
169 struct pneigh_entry *next;
170 possible_net_t net;
171 struct net_device *dev;
172 u8 flags;
173 u8 key[0];
174};
175
176/*
177 * neighbour table manipulation
178 */
179
180#define NEIGH_NUM_HASH_RND 4
181
182struct neigh_hash_table {
183 struct neighbour __rcu **hash_buckets;
184 unsigned int hash_shift;
185 __u32 hash_rnd[NEIGH_NUM_HASH_RND];
186 struct rcu_head rcu;
187};
188
189
190struct neigh_table {
191 int family;
192 int entry_size;
193 int key_len;
194 __be16 protocol;
195 __u32 (*hash)(const void *pkey,
196 const struct net_device *dev,
197 __u32 *hash_rnd);
198 bool (*key_eq)(const struct neighbour *, const void *pkey);
199 int (*constructor)(struct neighbour *);
200 int (*pconstructor)(struct pneigh_entry *);
201 void (*pdestructor)(struct pneigh_entry *);
202 void (*proxy_redo)(struct sk_buff *skb);
203 char *id;
204 struct neigh_parms parms;
205 struct list_head parms_list;
206 int gc_interval;
207 int gc_thresh1;
208 int gc_thresh2;
209 int gc_thresh3;
210 unsigned long last_flush;
211 struct delayed_work gc_work;
212 struct timer_list proxy_timer;
213 struct sk_buff_head proxy_queue;
214 atomic_t entries;
215 rwlock_t lock;
216 unsigned long last_rand;
217 struct neigh_statistics __percpu *stats;
218 struct neigh_hash_table __rcu *nht;
219 struct pneigh_entry **phash_buckets;
220};
221
222enum {
223 NEIGH_ARP_TABLE = 0,
224 NEIGH_ND_TABLE = 1,
225 NEIGH_DN_TABLE = 2,
226 NEIGH_NR_TABLES,
227 NEIGH_LINK_TABLE = NEIGH_NR_TABLES /* Pseudo table for neigh_xmit */
228};
229
230static inline int neigh_parms_family(struct neigh_parms *p)
231{
232 return p->tbl->family;
233}
234
235#define NEIGH_PRIV_ALIGN sizeof(long long)
236#define NEIGH_ENTRY_SIZE(size) ALIGN((size), NEIGH_PRIV_ALIGN)
237
238static inline void *neighbour_priv(const struct neighbour *n)
239{
240 return (char *)n + n->tbl->entry_size;
241}
242
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
249
250
251static inline bool neigh_key_eq16(const struct neighbour *n, const void *pkey)
252{
253 return *(const u16 *)n->primary_key == *(const u16 *)pkey;
254}
255
256static inline bool neigh_key_eq32(const struct neighbour *n, const void *pkey)
257{
258 return *(const u32 *)n->primary_key == *(const u32 *)pkey;
259}
260
261static inline bool neigh_key_eq128(const struct neighbour *n, const void *pkey)
262{
263 const u32 *n32 = (const u32 *)n->primary_key;
264 const u32 *p32 = pkey;
265
266 return ((n32[0] ^ p32[0]) | (n32[1] ^ p32[1]) |
267 (n32[2] ^ p32[2]) | (n32[3] ^ p32[3])) == 0;
268}
269
270static inline struct neighbour *___neigh_lookup_noref(
271 struct neigh_table *tbl,
272 bool (*key_eq)(const struct neighbour *n, const void *pkey),
273 __u32 (*hash)(const void *pkey,
274 const struct net_device *dev,
275 __u32 *hash_rnd),
276 const void *pkey,
277 struct net_device *dev)
278{
279 struct neigh_hash_table *nht = rcu_dereference_bh(tbl->nht);
280 struct neighbour *n;
281 u32 hash_val;
282
283 hash_val = hash(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
284 for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
285 n != NULL;
286 n = rcu_dereference_bh(n->next)) {
287 if (n->dev == dev && key_eq(n, pkey))
288 return n;
289 }
290
291 return NULL;
292}
293
294static inline struct neighbour *__neigh_lookup_noref(struct neigh_table *tbl,
295 const void *pkey,
296 struct net_device *dev)
297{
298 return ___neigh_lookup_noref(tbl, tbl->key_eq, tbl->hash, pkey, dev);
299}
300
301void neigh_table_init(int index, struct neigh_table *tbl);
302int neigh_table_clear(int index, struct neigh_table *tbl);
303struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
304 struct net_device *dev);
305struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net,
306 const void *pkey);
307struct neighbour *__neigh_create(struct neigh_table *tbl, const void *pkey,
308 struct net_device *dev, bool want_ref);
309static inline struct neighbour *neigh_create(struct neigh_table *tbl,
310 const void *pkey,
311 struct net_device *dev)
312{
313 return __neigh_create(tbl, pkey, dev, true);
314}
315void neigh_destroy(struct neighbour *neigh);
316int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb);
317int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new, u32 flags);
318void __neigh_set_probe_once(struct neighbour *neigh);
319void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev);
320int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev);
321int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb);
322int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb);
323int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb);
324struct neighbour *neigh_event_ns(struct neigh_table *tbl,
325 u8 *lladdr, void *saddr,
326 struct net_device *dev);
327
328struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
329 struct neigh_table *tbl);
330void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms);
331
332static inline
333struct net *neigh_parms_net(const struct neigh_parms *parms)
334{
335 return read_pnet(&parms->net);
336}
337
338unsigned long neigh_rand_reach_time(unsigned long base);
339
340void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
341 struct sk_buff *skb);
342struct pneigh_entry *pneigh_lookup(struct neigh_table *tbl, struct net *net,
343 const void *key, struct net_device *dev,
344 int creat);
345struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl, struct net *net,
346 const void *key, struct net_device *dev);
347int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *key,
348 struct net_device *dev);
349
350static inline struct net *pneigh_net(const struct pneigh_entry *pneigh)
351{
352 return read_pnet(&pneigh->net);
353}
354
355void neigh_app_ns(struct neighbour *n);
356void neigh_for_each(struct neigh_table *tbl,
357 void (*cb)(struct neighbour *, void *), void *cookie);
358void __neigh_for_each_release(struct neigh_table *tbl,
359 int (*cb)(struct neighbour *));
360int neigh_xmit(int fam, struct net_device *, const void *, struct sk_buff *);
361void pneigh_for_each(struct neigh_table *tbl,
362 void (*cb)(struct pneigh_entry *));
363
364struct neigh_seq_state {
365 struct seq_net_private p;
366 struct neigh_table *tbl;
367 struct neigh_hash_table *nht;
368 void *(*neigh_sub_iter)(struct neigh_seq_state *state,
369 struct neighbour *n, loff_t *pos);
370 unsigned int bucket;
371 unsigned int flags;
372#define NEIGH_SEQ_NEIGH_ONLY 0x00000001
373#define NEIGH_SEQ_IS_PNEIGH 0x00000002
374#define NEIGH_SEQ_SKIP_NOARP 0x00000004
375};
376void *neigh_seq_start(struct seq_file *, loff_t *, struct neigh_table *,
377 unsigned int);
378void *neigh_seq_next(struct seq_file *, void *, loff_t *);
379void neigh_seq_stop(struct seq_file *, void *);
380
381int neigh_proc_dointvec(struct ctl_table *ctl, int write,
382 void __user *buffer, size_t *lenp, loff_t *ppos);
383int neigh_proc_dointvec_jiffies(struct ctl_table *ctl, int write,
384 void __user *buffer,
385 size_t *lenp, loff_t *ppos);
386int neigh_proc_dointvec_ms_jiffies(struct ctl_table *ctl, int write,
387 void __user *buffer,
388 size_t *lenp, loff_t *ppos);
389
390int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
391 proc_handler *proc_handler);
392void neigh_sysctl_unregister(struct neigh_parms *p);
393
394static inline void __neigh_parms_put(struct neigh_parms *parms)
395{
396 atomic_dec(&parms->refcnt);
397}
398
399static inline struct neigh_parms *neigh_parms_clone(struct neigh_parms *parms)
400{
401 atomic_inc(&parms->refcnt);
402 return parms;
403}
404
405/*
406 * Neighbour references
407 */
408
409static inline void neigh_release(struct neighbour *neigh)
410{
411 if (atomic_dec_and_test(&neigh->refcnt))
412 neigh_destroy(neigh);
413}
414
415static inline struct neighbour * neigh_clone(struct neighbour *neigh)
416{
417 if (neigh)
418 atomic_inc(&neigh->refcnt);
419 return neigh;
420}
421
422#define neigh_hold(n) atomic_inc(&(n)->refcnt)
423
424static inline int neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
425{
426 unsigned long now = jiffies;
427
428 if (neigh->used != now)
429 neigh->used = now;
430 if (!(neigh->nud_state&(NUD_CONNECTED|NUD_DELAY|NUD_PROBE)))
431 return __neigh_event_send(neigh, skb);
432 return 0;
433}
434
435#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
436static inline int neigh_hh_bridge(struct hh_cache *hh, struct sk_buff *skb)
437{
438 unsigned int seq, hh_alen;
439
440 do {
441 seq = read_seqbegin(&hh->hh_lock);
442 hh_alen = HH_DATA_ALIGN(ETH_HLEN);
443 memcpy(skb->data - hh_alen, hh->hh_data, ETH_ALEN + hh_alen - ETH_HLEN);
444 } while (read_seqretry(&hh->hh_lock, seq));
445 return 0;
446}
447#endif
448
449static inline int neigh_hh_output(const struct hh_cache *hh, struct sk_buff *skb)
450{
451 unsigned int seq;
452 int hh_len;
453
454 do {
455 seq = read_seqbegin(&hh->hh_lock);
456 hh_len = hh->hh_len;
457 if (likely(hh_len <= HH_DATA_MOD)) {
458 /* this is inlined by gcc */
459 memcpy(skb->data - HH_DATA_MOD, hh->hh_data, HH_DATA_MOD);
460 } else {
461 int hh_alen = HH_DATA_ALIGN(hh_len);
462
463 memcpy(skb->data - hh_alen, hh->hh_data, hh_alen);
464 }
465 } while (read_seqretry(&hh->hh_lock, seq));
466
467 skb_push(skb, hh_len);
468 return dev_queue_xmit(skb);
469}
470
471static inline struct neighbour *
472__neigh_lookup(struct neigh_table *tbl, const void *pkey, struct net_device *dev, int creat)
473{
474 struct neighbour *n = neigh_lookup(tbl, pkey, dev);
475
476 if (n || !creat)
477 return n;
478
479 n = neigh_create(tbl, pkey, dev);
480 return IS_ERR(n) ? NULL : n;
481}
482
483static inline struct neighbour *
484__neigh_lookup_errno(struct neigh_table *tbl, const void *pkey,
485 struct net_device *dev)
486{
487 struct neighbour *n = neigh_lookup(tbl, pkey, dev);
488
489 if (n)
490 return n;
491
492 return neigh_create(tbl, pkey, dev);
493}
494
495struct neighbour_cb {
496 unsigned long sched_next;
497 unsigned int flags;
498};
499
500#define LOCALLY_ENQUEUED 0x1
501
502#define NEIGH_CB(skb) ((struct neighbour_cb *)(skb)->cb)
503
504static inline void neigh_ha_snapshot(char *dst, const struct neighbour *n,
505 const struct net_device *dev)
506{
507 unsigned int seq;
508
509 do {
510 seq = read_seqbegin(&n->ha_lock);
511 memcpy(dst, n->ha, dev->addr_len);
512 } while (read_seqretry(&n->ha_lock, seq));
513}
514
515
516#endif