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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_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,
50 NEIGH_VAR_PROXY_QLEN,
51 NEIGH_VAR_ANYCAST_DELAY,
52 NEIGH_VAR_PROXY_DELAY,
53 NEIGH_VAR_LOCKTIME,
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,
61 NEIGH_VAR_GC_THRESH1,
62 NEIGH_VAR_GC_THRESH2,
63 NEIGH_VAR_GC_THRESH3,
64 NEIGH_VAR_MAX
65};
66
67struct neigh_parms {
68#ifdef CONFIG_NET_NS
69 struct net *net;
70#endif
71 struct net_device *dev;
72 struct neigh_parms *next;
73 int (*neigh_setup)(struct neighbour *);
74 void (*neigh_cleanup)(struct neighbour *);
75 struct neigh_table *tbl;
76
77 void *sysctl_table;
78
79 int dead;
80 atomic_t refcnt;
81 struct rcu_head rcu_head;
82
83 int reachable_time;
84 int data[NEIGH_VAR_DATA_MAX];
85 DECLARE_BITMAP(data_state, NEIGH_VAR_DATA_MAX);
86};
87
88static inline void neigh_var_set(struct neigh_parms *p, int index, int val)
89{
90 set_bit(index, p->data_state);
91 p->data[index] = val;
92}
93
94#define NEIGH_VAR(p, attr) ((p)->data[NEIGH_VAR_ ## attr])
95
96/* In ndo_neigh_setup, NEIGH_VAR_INIT should be used.
97 * In other cases, NEIGH_VAR_SET should be used.
98 */
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)
101
102static inline void neigh_parms_data_state_setall(struct neigh_parms *p)
103{
104 bitmap_fill(p->data_state, NEIGH_VAR_DATA_MAX);
105}
106
107static inline void neigh_parms_data_state_cleanall(struct neigh_parms *p)
108{
109 bitmap_zero(p->data_state, NEIGH_VAR_DATA_MAX);
110}
111
112struct 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 */
116
117 unsigned long res_failed; /* number of failed resolutions */
118
119 unsigned long lookups; /* number of lookups */
120 unsigned long hits; /* number of hits (among lookups) */
121
122 unsigned long rcv_probes_mcast; /* number of received mcast ipv6 */
123 unsigned long rcv_probes_ucast; /* number of received ucast ipv6 */
124
125 unsigned long periodic_gc_runs; /* number of periodic GC runs */
126 unsigned long forced_gc_runs; /* number of forced GC runs */
127
128 unsigned long unres_discards; /* number of unresolved drops */
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#ifdef CONFIG_NET_NS
171 struct net *net;
172#endif
173 struct net_device *dev;
174 u8 flags;
175 u8 key[0];
176};
177
178/*
179 * neighbour table manipulation
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 struct neigh_table *next;
194 int family;
195 int entry_size;
196 int key_len;
197 __u32 (*hash)(const void *pkey,
198 const struct net_device *dev,
199 __u32 *hash_rnd);
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);
204 char *id;
205 struct neigh_parms parms;
206 /* HACK. gc_* should follow parms without a gap! */
207 int gc_interval;
208 int gc_thresh1;
209 int gc_thresh2;
210 int gc_thresh3;
211 unsigned long last_flush;
212 struct delayed_work gc_work;
213 struct timer_list proxy_timer;
214 struct sk_buff_head proxy_queue;
215 atomic_t entries;
216 rwlock_t lock;
217 unsigned long last_rand;
218 struct neigh_statistics __percpu *stats;
219 struct neigh_hash_table __rcu *nht;
220 struct pneigh_entry **phash_buckets;
221};
222
223static inline int neigh_parms_family(struct neigh_parms *p)
224{
225 return p->tbl->family;
226}
227
228#define NEIGH_PRIV_ALIGN sizeof(long long)
229#define NEIGH_ENTRY_SIZE(size) ALIGN((size), NEIGH_PRIV_ALIGN)
230
231static inline void *neighbour_priv(const struct neighbour *n)
232{
233 return (char *)n + n->tbl->entry_size;
234}
235
236/* flags for neigh_update() */
237#define NEIGH_UPDATE_F_OVERRIDE 0x00000001
238#define NEIGH_UPDATE_F_WEAK_OVERRIDE 0x00000002
239#define NEIGH_UPDATE_F_OVERRIDE_ISROUTER 0x00000004
240#define NEIGH_UPDATE_F_ISROUTER 0x40000000
241#define NEIGH_UPDATE_F_ADMIN 0x80000000
242
243void neigh_table_init(struct neigh_table *tbl);
244int neigh_table_clear(struct neigh_table *tbl);
245struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
246 struct net_device *dev);
247struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net,
248 const void *pkey);
249struct neighbour *__neigh_create(struct neigh_table *tbl, const void *pkey,
250 struct net_device *dev, bool want_ref);
251static inline struct neighbour *neigh_create(struct neigh_table *tbl,
252 const void *pkey,
253 struct net_device *dev)
254{
255 return __neigh_create(tbl, pkey, dev, true);
256}
257void neigh_destroy(struct neighbour *neigh);
258int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb);
259int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new, u32 flags);
260void __neigh_set_probe_once(struct neighbour *neigh);
261void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev);
262int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev);
263int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb);
264int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb);
265int neigh_compat_output(struct neighbour *neigh, struct sk_buff *skb);
266int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb);
267struct neighbour *neigh_event_ns(struct neigh_table *tbl,
268 u8 *lladdr, void *saddr,
269 struct net_device *dev);
270
271struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
272 struct neigh_table *tbl);
273void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms);
274
275static inline
276struct net *neigh_parms_net(const struct neigh_parms *parms)
277{
278 return read_pnet(&parms->net);
279}
280
281unsigned long neigh_rand_reach_time(unsigned long base);
282
283void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
284 struct sk_buff *skb);
285struct pneigh_entry *pneigh_lookup(struct neigh_table *tbl, struct net *net,
286 const void *key, struct net_device *dev,
287 int creat);
288struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl, struct net *net,
289 const void *key, struct net_device *dev);
290int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *key,
291 struct net_device *dev);
292
293static inline struct net *pneigh_net(const struct pneigh_entry *pneigh)
294{
295 return read_pnet(&pneigh->net);
296}
297
298void neigh_app_ns(struct neighbour *n);
299void neigh_for_each(struct neigh_table *tbl,
300 void (*cb)(struct neighbour *, void *), void *cookie);
301void __neigh_for_each_release(struct neigh_table *tbl,
302 int (*cb)(struct neighbour *));
303void pneigh_for_each(struct neigh_table *tbl,
304 void (*cb)(struct pneigh_entry *));
305
306struct neigh_seq_state {
307 struct seq_net_private p;
308 struct neigh_table *tbl;
309 struct neigh_hash_table *nht;
310 void *(*neigh_sub_iter)(struct neigh_seq_state *state,
311 struct neighbour *n, loff_t *pos);
312 unsigned int bucket;
313 unsigned int flags;
314#define NEIGH_SEQ_NEIGH_ONLY 0x00000001
315#define NEIGH_SEQ_IS_PNEIGH 0x00000002
316#define NEIGH_SEQ_SKIP_NOARP 0x00000004
317};
318void *neigh_seq_start(struct seq_file *, loff_t *, struct neigh_table *,
319 unsigned int);
320void *neigh_seq_next(struct seq_file *, void *, loff_t *);
321void neigh_seq_stop(struct seq_file *, void *);
322
323int neigh_proc_dointvec(struct ctl_table *ctl, int write,
324 void __user *buffer, size_t *lenp, loff_t *ppos);
325int neigh_proc_dointvec_jiffies(struct ctl_table *ctl, int write,
326 void __user *buffer,
327 size_t *lenp, loff_t *ppos);
328int neigh_proc_dointvec_ms_jiffies(struct ctl_table *ctl, int write,
329 void __user *buffer,
330 size_t *lenp, loff_t *ppos);
331
332int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
333 proc_handler *proc_handler);
334void neigh_sysctl_unregister(struct neigh_parms *p);
335
336static inline void __neigh_parms_put(struct neigh_parms *parms)
337{
338 atomic_dec(&parms->refcnt);
339}
340
341static inline struct neigh_parms *neigh_parms_clone(struct neigh_parms *parms)
342{
343 atomic_inc(&parms->refcnt);
344 return parms;
345}
346
347/*
348 * Neighbour references
349 */
350
351static inline void neigh_release(struct neighbour *neigh)
352{
353 if (atomic_dec_and_test(&neigh->refcnt))
354 neigh_destroy(neigh);
355}
356
357static inline struct neighbour * neigh_clone(struct neighbour *neigh)
358{
359 if (neigh)
360 atomic_inc(&neigh->refcnt);
361 return neigh;
362}
363
364#define neigh_hold(n) atomic_inc(&(n)->refcnt)
365
366static inline int neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
367{
368 unsigned long now = jiffies;
369
370 if (neigh->used != now)
371 neigh->used = now;
372 if (!(neigh->nud_state&(NUD_CONNECTED|NUD_DELAY|NUD_PROBE)))
373 return __neigh_event_send(neigh, skb);
374 return 0;
375}
376
377#ifdef CONFIG_BRIDGE_NETFILTER
378static inline int neigh_hh_bridge(struct hh_cache *hh, struct sk_buff *skb)
379{
380 unsigned int seq, hh_alen;
381
382 do {
383 seq = read_seqbegin(&hh->hh_lock);
384 hh_alen = HH_DATA_ALIGN(ETH_HLEN);
385 memcpy(skb->data - hh_alen, hh->hh_data, ETH_ALEN + hh_alen - ETH_HLEN);
386 } while (read_seqretry(&hh->hh_lock, seq));
387 return 0;
388}
389#endif
390
391static inline int neigh_hh_output(const struct hh_cache *hh, struct sk_buff *skb)
392{
393 unsigned int seq;
394 int hh_len;
395
396 do {
397 seq = read_seqbegin(&hh->hh_lock);
398 hh_len = hh->hh_len;
399 if (likely(hh_len <= HH_DATA_MOD)) {
400 /* this is inlined by gcc */
401 memcpy(skb->data - HH_DATA_MOD, hh->hh_data, HH_DATA_MOD);
402 } else {
403 int hh_alen = HH_DATA_ALIGN(hh_len);
404
405 memcpy(skb->data - hh_alen, hh->hh_data, hh_alen);
406 }
407 } while (read_seqretry(&hh->hh_lock, seq));
408
409 skb_push(skb, hh_len);
410 return dev_queue_xmit(skb);
411}
412
413static inline struct neighbour *
414__neigh_lookup(struct neigh_table *tbl, const void *pkey, struct net_device *dev, int creat)
415{
416 struct neighbour *n = neigh_lookup(tbl, pkey, dev);
417
418 if (n || !creat)
419 return n;
420
421 n = neigh_create(tbl, pkey, dev);
422 return IS_ERR(n) ? NULL : n;
423}
424
425static inline struct neighbour *
426__neigh_lookup_errno(struct neigh_table *tbl, const void *pkey,
427 struct net_device *dev)
428{
429 struct neighbour *n = neigh_lookup(tbl, pkey, dev);
430
431 if (n)
432 return n;
433
434 return neigh_create(tbl, pkey, dev);
435}
436
437struct neighbour_cb {
438 unsigned long sched_next;
439 unsigned int flags;
440};
441
442#define LOCALLY_ENQUEUED 0x1
443
444#define NEIGH_CB(skb) ((struct neighbour_cb *)(skb)->cb)
445
446static inline void neigh_ha_snapshot(char *dst, const struct neighbour *n,
447 const struct net_device *dev)
448{
449 unsigned int seq;
450
451 do {
452 seq = read_seqbegin(&n->ha_lock);
453 memcpy(dst, n->ha, dev->addr_len);
454 } while (read_seqretry(&n->ha_lock, seq));
455}
456#endif
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 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 * neighbour table manipulation
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 /* Pseudo table for neigh_xmit */
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/* 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
251
252
253static inline bool neigh_key_eq16(const struct neighbour *n, const void *pkey)
254{
255 return *(const u16 *)n->primary_key == *(const u16 *)pkey;
256}
257
258static inline bool neigh_key_eq32(const struct neighbour *n, const void *pkey)
259{
260 return *(const u32 *)n->primary_key == *(const u32 *)pkey;
261}
262
263static inline bool neigh_key_eq128(const struct neighbour *n, const void *pkey)
264{
265 const u32 *n32 = (const u32 *)n->primary_key;
266 const u32 *p32 = pkey;
267
268 return ((n32[0] ^ p32[0]) | (n32[1] ^ p32[1]) |
269 (n32[2] ^ p32[2]) | (n32[3] ^ p32[3])) == 0;
270}
271
272static 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,
277 __u32 *hash_rnd),
278 const void *pkey,
279 struct net_device *dev)
280{
281 struct neigh_hash_table *nht = rcu_dereference_bh(tbl->nht);
282 struct neighbour *n;
283 u32 hash_val;
284
285 hash_val = hash(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
286 for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
287 n != NULL;
288 n = rcu_dereference_bh(n->next)) {
289 if (n->dev == dev && key_eq(n, pkey))
290 return n;
291 }
292
293 return NULL;
294}
295
296static inline struct neighbour *__neigh_lookup_noref(struct neigh_table *tbl,
297 const void *pkey,
298 struct net_device *dev)
299{
300 return ___neigh_lookup_noref(tbl, tbl->key_eq, tbl->hash, pkey, dev);
301}
302
303void neigh_table_init(int index, struct neigh_table *tbl);
304int neigh_table_clear(int index, struct neigh_table *tbl);
305struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
306 struct net_device *dev);
307struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net,
308 const void *pkey);
309struct neighbour *__neigh_create(struct neigh_table *tbl, const void *pkey,
310 struct net_device *dev, bool want_ref);
311static inline struct neighbour *neigh_create(struct neigh_table *tbl,
312 const void *pkey,
313 struct net_device *dev)
314{
315 return __neigh_create(tbl, pkey, dev, true);
316}
317void neigh_destroy(struct neighbour *neigh);
318int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb);
319int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new, u32 flags,
320 u32 nlmsg_pid);
321void __neigh_set_probe_once(struct neighbour *neigh);
322bool neigh_remove_one(struct neighbour *ndel, struct neigh_table *tbl);
323void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev);
324int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev);
325int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb);
326int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb);
327int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb);
328struct neighbour *neigh_event_ns(struct neigh_table *tbl,
329 u8 *lladdr, void *saddr,
330 struct net_device *dev);
331
332struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
333 struct neigh_table *tbl);
334void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms);
335
336static inline
337struct net *neigh_parms_net(const struct neigh_parms *parms)
338{
339 return read_pnet(&parms->net);
340}
341
342unsigned long neigh_rand_reach_time(unsigned long base);
343
344void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
345 struct sk_buff *skb);
346struct pneigh_entry *pneigh_lookup(struct neigh_table *tbl, struct net *net,
347 const void *key, struct net_device *dev,
348 int creat);
349struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl, struct net *net,
350 const void *key, struct net_device *dev);
351int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *key,
352 struct net_device *dev);
353
354static inline struct net *pneigh_net(const struct pneigh_entry *pneigh)
355{
356 return read_pnet(&pneigh->net);
357}
358
359void neigh_app_ns(struct neighbour *n);
360void neigh_for_each(struct neigh_table *tbl,
361 void (*cb)(struct neighbour *, void *), void *cookie);
362void __neigh_for_each_release(struct neigh_table *tbl,
363 int (*cb)(struct neighbour *));
364int neigh_xmit(int fam, struct net_device *, const void *, struct sk_buff *);
365void pneigh_for_each(struct neigh_table *tbl,
366 void (*cb)(struct pneigh_entry *));
367
368struct 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);
374 unsigned int bucket;
375 unsigned int flags;
376#define NEIGH_SEQ_NEIGH_ONLY 0x00000001
377#define NEIGH_SEQ_IS_PNEIGH 0x00000002
378#define NEIGH_SEQ_SKIP_NOARP 0x00000004
379};
380void *neigh_seq_start(struct seq_file *, loff_t *, struct neigh_table *,
381 unsigned int);
382void *neigh_seq_next(struct seq_file *, void *, loff_t *);
383void neigh_seq_stop(struct seq_file *, void *);
384
385int neigh_proc_dointvec(struct ctl_table *ctl, int write,
386 void __user *buffer, size_t *lenp, loff_t *ppos);
387int neigh_proc_dointvec_jiffies(struct ctl_table *ctl, int write,
388 void __user *buffer,
389 size_t *lenp, loff_t *ppos);
390int neigh_proc_dointvec_ms_jiffies(struct ctl_table *ctl, int write,
391 void __user *buffer,
392 size_t *lenp, loff_t *ppos);
393
394int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
395 proc_handler *proc_handler);
396void neigh_sysctl_unregister(struct neigh_parms *p);
397
398static inline void __neigh_parms_put(struct neigh_parms *parms)
399{
400 refcount_dec(&parms->refcnt);
401}
402
403static inline struct neigh_parms *neigh_parms_clone(struct neigh_parms *parms)
404{
405 refcount_inc(&parms->refcnt);
406 return parms;
407}
408
409/*
410 * Neighbour references
411 */
412
413static inline void neigh_release(struct neighbour *neigh)
414{
415 if (refcount_dec_and_test(&neigh->refcnt))
416 neigh_destroy(neigh);
417}
418
419static inline struct neighbour * neigh_clone(struct neighbour *neigh)
420{
421 if (neigh)
422 refcount_inc(&neigh->refcnt);
423 return neigh;
424}
425
426#define neigh_hold(n) refcount_inc(&(n)->refcnt)
427
428static inline int neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
429{
430 unsigned long now = jiffies;
431
432 if (neigh->used != now)
433 neigh->used = now;
434 if (!(neigh->nud_state&(NUD_CONNECTED|NUD_DELAY|NUD_PROBE)))
435 return __neigh_event_send(neigh, skb);
436 return 0;
437}
438
439#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
440static inline int neigh_hh_bridge(struct hh_cache *hh, struct sk_buff *skb)
441{
442 unsigned int seq, hh_alen;
443
444 do {
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));
449 return 0;
450}
451#endif
452
453static inline int neigh_hh_output(const struct hh_cache *hh, struct sk_buff *skb)
454{
455 unsigned int seq;
456 unsigned int hh_len;
457
458 do {
459 seq = read_seqbegin(&hh->hh_lock);
460 hh_len = hh->hh_len;
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);
464 } else {
465 unsigned int hh_alen = HH_DATA_ALIGN(hh_len);
466
467 memcpy(skb->data - hh_alen, hh->hh_data, hh_alen);
468 }
469 } while (read_seqretry(&hh->hh_lock, seq));
470
471 skb_push(skb, hh_len);
472 return dev_queue_xmit(skb);
473}
474
475static inline int neigh_output(struct neighbour *n, struct sk_buff *skb)
476{
477 const struct hh_cache *hh = &n->hh;
478
479 if ((n->nud_state & NUD_CONNECTED) && hh->hh_len)
480 return neigh_hh_output(hh, skb);
481 else
482 return n->output(n, skb);
483}
484
485static inline struct neighbour *
486__neigh_lookup(struct neigh_table *tbl, const void *pkey, struct net_device *dev, int creat)
487{
488 struct neighbour *n = neigh_lookup(tbl, pkey, dev);
489
490 if (n || !creat)
491 return n;
492
493 n = neigh_create(tbl, pkey, dev);
494 return IS_ERR(n) ? NULL : n;
495}
496
497static inline struct neighbour *
498__neigh_lookup_errno(struct neigh_table *tbl, const void *pkey,
499 struct net_device *dev)
500{
501 struct neighbour *n = neigh_lookup(tbl, pkey, dev);
502
503 if (n)
504 return n;
505
506 return neigh_create(tbl, pkey, dev);
507}
508
509struct neighbour_cb {
510 unsigned long sched_next;
511 unsigned int flags;
512};
513
514#define LOCALLY_ENQUEUED 0x1
515
516#define NEIGH_CB(skb) ((struct neighbour_cb *)(skb)->cb)
517
518static inline void neigh_ha_snapshot(char *dst, const struct neighbour *n,
519 const struct net_device *dev)
520{
521 unsigned int seq;
522
523 do {
524 seq = read_seqbegin(&n->ha_lock);
525 memcpy(dst, n->ha, dev->addr_len);
526 } while (read_seqretry(&n->ha_lock, seq));
527}
528
529
530#endif