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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_INTERVAL_PROBE_TIME_MS,
52 NEIGH_VAR_GC_STALETIME,
53 NEIGH_VAR_QUEUE_LEN_BYTES,
54 NEIGH_VAR_PROXY_QLEN,
55 NEIGH_VAR_ANYCAST_DELAY,
56 NEIGH_VAR_PROXY_DELAY,
57 NEIGH_VAR_LOCKTIME,
58#define NEIGH_VAR_DATA_MAX (NEIGH_VAR_LOCKTIME + 1)
59 /* Following are used as a second way to access one of the above */
60 NEIGH_VAR_QUEUE_LEN, /* same data as NEIGH_VAR_QUEUE_LEN_BYTES */
61 NEIGH_VAR_RETRANS_TIME_MS, /* same data as NEIGH_VAR_RETRANS_TIME */
62 NEIGH_VAR_BASE_REACHABLE_TIME_MS, /* same data as NEIGH_VAR_BASE_REACHABLE_TIME */
63 /* Following are used by "default" only */
64 NEIGH_VAR_GC_INTERVAL,
65 NEIGH_VAR_GC_THRESH1,
66 NEIGH_VAR_GC_THRESH2,
67 NEIGH_VAR_GC_THRESH3,
68 NEIGH_VAR_MAX
69};
70
71struct neigh_parms {
72 possible_net_t net;
73 struct net_device *dev;
74 netdevice_tracker dev_tracker;
75 struct list_head list;
76 int (*neigh_setup)(struct neighbour *);
77 struct neigh_table *tbl;
78
79 void *sysctl_table;
80
81 int dead;
82 refcount_t refcnt;
83 struct rcu_head rcu_head;
84
85 int reachable_time;
86 u32 qlen;
87 int data[NEIGH_VAR_DATA_MAX];
88 DECLARE_BITMAP(data_state, NEIGH_VAR_DATA_MAX);
89};
90
91static inline void neigh_var_set(struct neigh_parms *p, int index, int val)
92{
93 set_bit(index, p->data_state);
94 p->data[index] = val;
95}
96
97#define NEIGH_VAR(p, attr) ((p)->data[NEIGH_VAR_ ## attr])
98
99/* In ndo_neigh_setup, NEIGH_VAR_INIT should be used.
100 * In other cases, NEIGH_VAR_SET should be used.
101 */
102#define NEIGH_VAR_INIT(p, attr, val) (NEIGH_VAR(p, attr) = val)
103#define NEIGH_VAR_SET(p, attr, val) neigh_var_set(p, NEIGH_VAR_ ## attr, val)
104
105static inline void neigh_parms_data_state_setall(struct neigh_parms *p)
106{
107 bitmap_fill(p->data_state, NEIGH_VAR_DATA_MAX);
108}
109
110static inline void neigh_parms_data_state_cleanall(struct neigh_parms *p)
111{
112 bitmap_zero(p->data_state, NEIGH_VAR_DATA_MAX);
113}
114
115struct neigh_statistics {
116 unsigned long allocs; /* number of allocated neighs */
117 unsigned long destroys; /* number of destroyed neighs */
118 unsigned long hash_grows; /* number of hash resizes */
119
120 unsigned long res_failed; /* number of failed resolutions */
121
122 unsigned long lookups; /* number of lookups */
123 unsigned long hits; /* number of hits (among lookups) */
124
125 unsigned long rcv_probes_mcast; /* number of received mcast ipv6 */
126 unsigned long rcv_probes_ucast; /* number of received ucast ipv6 */
127
128 unsigned long periodic_gc_runs; /* number of periodic GC runs */
129 unsigned long forced_gc_runs; /* number of forced GC runs */
130
131 unsigned long unres_discards; /* number of unresolved drops */
132 unsigned long table_fulls; /* times even gc couldn't help */
133};
134
135#define NEIGH_CACHE_STAT_INC(tbl, field) this_cpu_inc((tbl)->stats->field)
136
137struct neighbour {
138 struct neighbour __rcu *next;
139 struct neigh_table *tbl;
140 struct neigh_parms *parms;
141 unsigned long confirmed;
142 unsigned long updated;
143 rwlock_t lock;
144 refcount_t refcnt;
145 unsigned int arp_queue_len_bytes;
146 struct sk_buff_head arp_queue;
147 struct timer_list timer;
148 unsigned long used;
149 atomic_t probes;
150 u8 nud_state;
151 u8 type;
152 u8 dead;
153 u8 protocol;
154 u32 flags;
155 seqlock_t ha_lock;
156 unsigned char ha[ALIGN(MAX_ADDR_LEN, sizeof(unsigned long))] __aligned(8);
157 struct hh_cache hh;
158 int (*output)(struct neighbour *, struct sk_buff *);
159 const struct neigh_ops *ops;
160 struct list_head gc_list;
161 struct list_head managed_list;
162 struct rcu_head rcu;
163 struct net_device *dev;
164 netdevice_tracker dev_tracker;
165 u8 primary_key[];
166} __randomize_layout;
167
168struct neigh_ops {
169 int family;
170 void (*solicit)(struct neighbour *, struct sk_buff *);
171 void (*error_report)(struct neighbour *, struct sk_buff *);
172 int (*output)(struct neighbour *, struct sk_buff *);
173 int (*connected_output)(struct neighbour *, struct sk_buff *);
174};
175
176struct pneigh_entry {
177 struct pneigh_entry *next;
178 possible_net_t net;
179 struct net_device *dev;
180 netdevice_tracker dev_tracker;
181 u32 flags;
182 u8 protocol;
183 u32 key[];
184};
185
186/*
187 * neighbour table manipulation
188 */
189
190#define NEIGH_NUM_HASH_RND 4
191
192struct neigh_hash_table {
193 struct neighbour __rcu **hash_buckets;
194 unsigned int hash_shift;
195 __u32 hash_rnd[NEIGH_NUM_HASH_RND];
196 struct rcu_head rcu;
197};
198
199
200struct neigh_table {
201 int family;
202 unsigned int entry_size;
203 unsigned int key_len;
204 __be16 protocol;
205 __u32 (*hash)(const void *pkey,
206 const struct net_device *dev,
207 __u32 *hash_rnd);
208 bool (*key_eq)(const struct neighbour *, const void *pkey);
209 int (*constructor)(struct neighbour *);
210 int (*pconstructor)(struct pneigh_entry *);
211 void (*pdestructor)(struct pneigh_entry *);
212 void (*proxy_redo)(struct sk_buff *skb);
213 int (*is_multicast)(const void *pkey);
214 bool (*allow_add)(const struct net_device *dev,
215 struct netlink_ext_ack *extack);
216 char *id;
217 struct neigh_parms parms;
218 struct list_head parms_list;
219 int gc_interval;
220 int gc_thresh1;
221 int gc_thresh2;
222 int gc_thresh3;
223 unsigned long last_flush;
224 struct delayed_work gc_work;
225 struct delayed_work managed_work;
226 struct timer_list proxy_timer;
227 struct sk_buff_head proxy_queue;
228 atomic_t entries;
229 atomic_t gc_entries;
230 struct list_head gc_list;
231 struct list_head managed_list;
232 rwlock_t lock;
233 unsigned long last_rand;
234 struct neigh_statistics __percpu *stats;
235 struct neigh_hash_table __rcu *nht;
236 struct pneigh_entry **phash_buckets;
237};
238
239enum {
240 NEIGH_ARP_TABLE = 0,
241 NEIGH_ND_TABLE = 1,
242 NEIGH_DN_TABLE = 2,
243 NEIGH_NR_TABLES,
244 NEIGH_LINK_TABLE = NEIGH_NR_TABLES /* Pseudo table for neigh_xmit */
245};
246
247static inline int neigh_parms_family(struct neigh_parms *p)
248{
249 return p->tbl->family;
250}
251
252#define NEIGH_PRIV_ALIGN sizeof(long long)
253#define NEIGH_ENTRY_SIZE(size) ALIGN((size), NEIGH_PRIV_ALIGN)
254
255static inline void *neighbour_priv(const struct neighbour *n)
256{
257 return (char *)n + n->tbl->entry_size;
258}
259
260/* flags for neigh_update() */
261#define NEIGH_UPDATE_F_OVERRIDE BIT(0)
262#define NEIGH_UPDATE_F_WEAK_OVERRIDE BIT(1)
263#define NEIGH_UPDATE_F_OVERRIDE_ISROUTER BIT(2)
264#define NEIGH_UPDATE_F_USE BIT(3)
265#define NEIGH_UPDATE_F_MANAGED BIT(4)
266#define NEIGH_UPDATE_F_EXT_LEARNED BIT(5)
267#define NEIGH_UPDATE_F_ISROUTER BIT(6)
268#define NEIGH_UPDATE_F_ADMIN BIT(7)
269
270/* In-kernel representation for NDA_FLAGS_EXT flags: */
271#define NTF_OLD_MASK 0xff
272#define NTF_EXT_SHIFT 8
273#define NTF_EXT_MASK (NTF_EXT_MANAGED)
274
275#define NTF_MANAGED (NTF_EXT_MANAGED << NTF_EXT_SHIFT)
276
277extern const struct nla_policy nda_policy[];
278
279static inline bool neigh_key_eq32(const struct neighbour *n, const void *pkey)
280{
281 return *(const u32 *)n->primary_key == *(const u32 *)pkey;
282}
283
284static inline bool neigh_key_eq128(const struct neighbour *n, const void *pkey)
285{
286 const u32 *n32 = (const u32 *)n->primary_key;
287 const u32 *p32 = pkey;
288
289 return ((n32[0] ^ p32[0]) | (n32[1] ^ p32[1]) |
290 (n32[2] ^ p32[2]) | (n32[3] ^ p32[3])) == 0;
291}
292
293static inline struct neighbour *___neigh_lookup_noref(
294 struct neigh_table *tbl,
295 bool (*key_eq)(const struct neighbour *n, const void *pkey),
296 __u32 (*hash)(const void *pkey,
297 const struct net_device *dev,
298 __u32 *hash_rnd),
299 const void *pkey,
300 struct net_device *dev)
301{
302 struct neigh_hash_table *nht = rcu_dereference(tbl->nht);
303 struct neighbour *n;
304 u32 hash_val;
305
306 hash_val = hash(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift);
307 for (n = rcu_dereference(nht->hash_buckets[hash_val]);
308 n != NULL;
309 n = rcu_dereference(n->next)) {
310 if (n->dev == dev && key_eq(n, pkey))
311 return n;
312 }
313
314 return NULL;
315}
316
317static inline struct neighbour *__neigh_lookup_noref(struct neigh_table *tbl,
318 const void *pkey,
319 struct net_device *dev)
320{
321 return ___neigh_lookup_noref(tbl, tbl->key_eq, tbl->hash, pkey, dev);
322}
323
324static inline void neigh_confirm(struct neighbour *n)
325{
326 if (n) {
327 unsigned long now = jiffies;
328
329 /* avoid dirtying neighbour */
330 if (READ_ONCE(n->confirmed) != now)
331 WRITE_ONCE(n->confirmed, now);
332 }
333}
334
335void neigh_table_init(int index, struct neigh_table *tbl);
336int neigh_table_clear(int index, struct neigh_table *tbl);
337struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
338 struct net_device *dev);
339struct neighbour *__neigh_create(struct neigh_table *tbl, const void *pkey,
340 struct net_device *dev, bool want_ref);
341static inline struct neighbour *neigh_create(struct neigh_table *tbl,
342 const void *pkey,
343 struct net_device *dev)
344{
345 return __neigh_create(tbl, pkey, dev, true);
346}
347void neigh_destroy(struct neighbour *neigh);
348int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb,
349 const bool immediate_ok);
350int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new, u32 flags,
351 u32 nlmsg_pid);
352void __neigh_set_probe_once(struct neighbour *neigh);
353bool neigh_remove_one(struct neighbour *ndel, struct neigh_table *tbl);
354void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev);
355int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev);
356int neigh_carrier_down(struct neigh_table *tbl, struct net_device *dev);
357int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb);
358int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb);
359int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb);
360struct neighbour *neigh_event_ns(struct neigh_table *tbl,
361 u8 *lladdr, void *saddr,
362 struct net_device *dev);
363
364struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
365 struct neigh_table *tbl);
366void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms);
367
368static inline
369struct net *neigh_parms_net(const struct neigh_parms *parms)
370{
371 return read_pnet(&parms->net);
372}
373
374unsigned long neigh_rand_reach_time(unsigned long base);
375
376void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
377 struct sk_buff *skb);
378struct pneigh_entry *pneigh_lookup(struct neigh_table *tbl, struct net *net,
379 const void *key, struct net_device *dev,
380 int creat);
381struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl, struct net *net,
382 const void *key, struct net_device *dev);
383int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *key,
384 struct net_device *dev);
385
386static inline struct net *pneigh_net(const struct pneigh_entry *pneigh)
387{
388 return read_pnet(&pneigh->net);
389}
390
391void neigh_app_ns(struct neighbour *n);
392void neigh_for_each(struct neigh_table *tbl,
393 void (*cb)(struct neighbour *, void *), void *cookie);
394void __neigh_for_each_release(struct neigh_table *tbl,
395 int (*cb)(struct neighbour *));
396int neigh_xmit(int fam, struct net_device *, const void *, struct sk_buff *);
397
398struct neigh_seq_state {
399 struct seq_net_private p;
400 struct neigh_table *tbl;
401 struct neigh_hash_table *nht;
402 void *(*neigh_sub_iter)(struct neigh_seq_state *state,
403 struct neighbour *n, loff_t *pos);
404 unsigned int bucket;
405 unsigned int flags;
406#define NEIGH_SEQ_NEIGH_ONLY 0x00000001
407#define NEIGH_SEQ_IS_PNEIGH 0x00000002
408#define NEIGH_SEQ_SKIP_NOARP 0x00000004
409};
410void *neigh_seq_start(struct seq_file *, loff_t *, struct neigh_table *,
411 unsigned int);
412void *neigh_seq_next(struct seq_file *, void *, loff_t *);
413void neigh_seq_stop(struct seq_file *, void *);
414
415int neigh_proc_dointvec(struct ctl_table *ctl, int write,
416 void *buffer, size_t *lenp, loff_t *ppos);
417int neigh_proc_dointvec_jiffies(struct ctl_table *ctl, int write,
418 void *buffer,
419 size_t *lenp, loff_t *ppos);
420int neigh_proc_dointvec_ms_jiffies(struct ctl_table *ctl, int write,
421 void *buffer, size_t *lenp, loff_t *ppos);
422
423int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
424 proc_handler *proc_handler);
425void neigh_sysctl_unregister(struct neigh_parms *p);
426
427static inline void __neigh_parms_put(struct neigh_parms *parms)
428{
429 refcount_dec(&parms->refcnt);
430}
431
432static inline struct neigh_parms *neigh_parms_clone(struct neigh_parms *parms)
433{
434 refcount_inc(&parms->refcnt);
435 return parms;
436}
437
438/*
439 * Neighbour references
440 */
441
442static inline void neigh_release(struct neighbour *neigh)
443{
444 if (refcount_dec_and_test(&neigh->refcnt))
445 neigh_destroy(neigh);
446}
447
448static inline struct neighbour * neigh_clone(struct neighbour *neigh)
449{
450 if (neigh)
451 refcount_inc(&neigh->refcnt);
452 return neigh;
453}
454
455#define neigh_hold(n) refcount_inc(&(n)->refcnt)
456
457static __always_inline int neigh_event_send_probe(struct neighbour *neigh,
458 struct sk_buff *skb,
459 const bool immediate_ok)
460{
461 unsigned long now = jiffies;
462
463 if (READ_ONCE(neigh->used) != now)
464 WRITE_ONCE(neigh->used, now);
465 if (!(READ_ONCE(neigh->nud_state) & (NUD_CONNECTED | NUD_DELAY | NUD_PROBE)))
466 return __neigh_event_send(neigh, skb, immediate_ok);
467 return 0;
468}
469
470static inline int neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
471{
472 return neigh_event_send_probe(neigh, skb, true);
473}
474
475#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
476static inline int neigh_hh_bridge(struct hh_cache *hh, struct sk_buff *skb)
477{
478 unsigned int seq, hh_alen;
479
480 do {
481 seq = read_seqbegin(&hh->hh_lock);
482 hh_alen = HH_DATA_ALIGN(ETH_HLEN);
483 memcpy(skb->data - hh_alen, hh->hh_data, ETH_ALEN + hh_alen - ETH_HLEN);
484 } while (read_seqretry(&hh->hh_lock, seq));
485 return 0;
486}
487#endif
488
489static inline int neigh_hh_output(const struct hh_cache *hh, struct sk_buff *skb)
490{
491 unsigned int hh_alen = 0;
492 unsigned int seq;
493 unsigned int hh_len;
494
495 do {
496 seq = read_seqbegin(&hh->hh_lock);
497 hh_len = READ_ONCE(hh->hh_len);
498 if (likely(hh_len <= HH_DATA_MOD)) {
499 hh_alen = HH_DATA_MOD;
500
501 /* skb_push() would proceed silently if we have room for
502 * the unaligned size but not for the aligned size:
503 * check headroom explicitly.
504 */
505 if (likely(skb_headroom(skb) >= HH_DATA_MOD)) {
506 /* this is inlined by gcc */
507 memcpy(skb->data - HH_DATA_MOD, hh->hh_data,
508 HH_DATA_MOD);
509 }
510 } else {
511 hh_alen = HH_DATA_ALIGN(hh_len);
512
513 if (likely(skb_headroom(skb) >= hh_alen)) {
514 memcpy(skb->data - hh_alen, hh->hh_data,
515 hh_alen);
516 }
517 }
518 } while (read_seqretry(&hh->hh_lock, seq));
519
520 if (WARN_ON_ONCE(skb_headroom(skb) < hh_alen)) {
521 kfree_skb(skb);
522 return NET_XMIT_DROP;
523 }
524
525 __skb_push(skb, hh_len);
526 return dev_queue_xmit(skb);
527}
528
529static inline int neigh_output(struct neighbour *n, struct sk_buff *skb,
530 bool skip_cache)
531{
532 const struct hh_cache *hh = &n->hh;
533
534 /* n->nud_state and hh->hh_len could be changed under us.
535 * neigh_hh_output() is taking care of the race later.
536 */
537 if (!skip_cache &&
538 (READ_ONCE(n->nud_state) & NUD_CONNECTED) &&
539 READ_ONCE(hh->hh_len))
540 return neigh_hh_output(hh, skb);
541
542 return READ_ONCE(n->output)(n, skb);
543}
544
545static inline struct neighbour *
546__neigh_lookup(struct neigh_table *tbl, const void *pkey, struct net_device *dev, int creat)
547{
548 struct neighbour *n = neigh_lookup(tbl, pkey, dev);
549
550 if (n || !creat)
551 return n;
552
553 n = neigh_create(tbl, pkey, dev);
554 return IS_ERR(n) ? NULL : n;
555}
556
557static inline struct neighbour *
558__neigh_lookup_errno(struct neigh_table *tbl, const void *pkey,
559 struct net_device *dev)
560{
561 struct neighbour *n = neigh_lookup(tbl, pkey, dev);
562
563 if (n)
564 return n;
565
566 return neigh_create(tbl, pkey, dev);
567}
568
569struct neighbour_cb {
570 unsigned long sched_next;
571 unsigned int flags;
572};
573
574#define LOCALLY_ENQUEUED 0x1
575
576#define NEIGH_CB(skb) ((struct neighbour_cb *)(skb)->cb)
577
578static inline void neigh_ha_snapshot(char *dst, const struct neighbour *n,
579 const struct net_device *dev)
580{
581 unsigned int seq;
582
583 do {
584 seq = read_seqbegin(&n->ha_lock);
585 memcpy(dst, n->ha, dev->addr_len);
586 } while (read_seqretry(&n->ha_lock, seq));
587}
588
589static inline void neigh_update_is_router(struct neighbour *neigh, u32 flags,
590 int *notify)
591{
592 u8 ndm_flags = 0;
593
594 ndm_flags |= (flags & NEIGH_UPDATE_F_ISROUTER) ? NTF_ROUTER : 0;
595 if ((neigh->flags ^ ndm_flags) & NTF_ROUTER) {
596 if (ndm_flags & NTF_ROUTER)
597 neigh->flags |= NTF_ROUTER;
598 else
599 neigh->flags &= ~NTF_ROUTER;
600 *notify = 1;
601 }
602}
603#endif