tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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
25#include <linux/err.h>
26#include <linux/sysctl.h>
27#include <linux/workqueue.h>
28#include <net/rtnetlink.h>
29
30/*
31 * NUD stands for "neighbor unreachability detection"
32 */
33
34#define NUD_IN_TIMER (NUD_INCOMPLETE|NUD_REACHABLE|NUD_DELAY|NUD_PROBE)
35#define NUD_VALID (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE|NUD_PROBE|NUD_STALE|NUD_DELAY)
36#define NUD_CONNECTED (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE)
37
38struct neighbour;
39
40struct neigh_parms {
41#ifdef CONFIG_NET_NS
42 struct net *net;
43#endif
44 struct net_device *dev;
45 struct neigh_parms *next;
46 int (*neigh_setup)(struct neighbour *);
47 void (*neigh_cleanup)(struct neighbour *);
48 struct neigh_table *tbl;
49
50 void *sysctl_table;
51
52 int dead;
53 atomic_t refcnt;
54 struct rcu_head rcu_head;
55
56 int base_reachable_time;
57 int retrans_time;
58 int gc_staletime;
59 int reachable_time;
60 int delay_probe_time;
61
62 int queue_len;
63 int ucast_probes;
64 int app_probes;
65 int mcast_probes;
66 int anycast_delay;
67 int proxy_delay;
68 int proxy_qlen;
69 int locktime;
70};
71
72struct neigh_statistics {
73 unsigned long allocs; /* number of allocated neighs */
74 unsigned long destroys; /* number of destroyed neighs */
75 unsigned long hash_grows; /* number of hash resizes */
76
77 unsigned long res_failed; /* number of failed resolutions */
78
79 unsigned long lookups; /* number of lookups */
80 unsigned long hits; /* number of hits (among lookups) */
81
82 unsigned long rcv_probes_mcast; /* number of received mcast ipv6 */
83 unsigned long rcv_probes_ucast; /* number of received ucast ipv6 */
84
85 unsigned long periodic_gc_runs; /* number of periodic GC runs */
86 unsigned long forced_gc_runs; /* number of forced GC runs */
87
88 unsigned long unres_discards; /* number of unresolved drops */
89};
90
91#define NEIGH_CACHE_STAT_INC(tbl, field) this_cpu_inc((tbl)->stats->field)
92
93struct neighbour {
94 struct neighbour __rcu *next;
95 struct neigh_table *tbl;
96 struct neigh_parms *parms;
97 unsigned long confirmed;
98 unsigned long updated;
99 rwlock_t lock;
100 atomic_t refcnt;
101 struct sk_buff_head arp_queue;
102 struct timer_list timer;
103 unsigned long used;
104 atomic_t probes;
105 __u8 flags;
106 __u8 nud_state;
107 __u8 type;
108 __u8 dead;
109 seqlock_t ha_lock;
110 unsigned char ha[ALIGN(MAX_ADDR_LEN, sizeof(unsigned long))];
111 struct hh_cache hh;
112 int (*output)(struct neighbour *, struct sk_buff *);
113 const struct neigh_ops *ops;
114 struct rcu_head rcu;
115 struct net_device *dev;
116 u8 primary_key[0];
117};
118
119struct neigh_ops {
120 int family;
121 void (*solicit)(struct neighbour *, struct sk_buff *);
122 void (*error_report)(struct neighbour *, struct sk_buff *);
123 int (*output)(struct neighbour *, struct sk_buff *);
124 int (*connected_output)(struct neighbour *, struct sk_buff *);
125};
126
127struct pneigh_entry {
128 struct pneigh_entry *next;
129#ifdef CONFIG_NET_NS
130 struct net *net;
131#endif
132 struct net_device *dev;
133 u8 flags;
134 u8 key[0];
135};
136
137/*
138 * neighbour table manipulation
139 */
140
141struct neigh_hash_table {
142 struct neighbour __rcu **hash_buckets;
143 unsigned int hash_shift;
144 __u32 hash_rnd;
145 struct rcu_head rcu;
146};
147
148
149struct neigh_table {
150 struct neigh_table *next;
151 int family;
152 int entry_size;
153 int key_len;
154 __u32 (*hash)(const void *pkey,
155 const struct net_device *dev,
156 __u32 hash_rnd);
157 int (*constructor)(struct neighbour *);
158 int (*pconstructor)(struct pneigh_entry *);
159 void (*pdestructor)(struct pneigh_entry *);
160 void (*proxy_redo)(struct sk_buff *skb);
161 char *id;
162 struct neigh_parms parms;
163 /* HACK. gc_* should follow parms without a gap! */
164 int gc_interval;
165 int gc_thresh1;
166 int gc_thresh2;
167 int gc_thresh3;
168 unsigned long last_flush;
169 struct delayed_work gc_work;
170 struct timer_list proxy_timer;
171 struct sk_buff_head proxy_queue;
172 atomic_t entries;
173 rwlock_t lock;
174 unsigned long last_rand;
175 struct kmem_cache *kmem_cachep;
176 struct neigh_statistics __percpu *stats;
177 struct neigh_hash_table __rcu *nht;
178 struct pneigh_entry **phash_buckets;
179};
180
181/* flags for neigh_update() */
182#define NEIGH_UPDATE_F_OVERRIDE 0x00000001
183#define NEIGH_UPDATE_F_WEAK_OVERRIDE 0x00000002
184#define NEIGH_UPDATE_F_OVERRIDE_ISROUTER 0x00000004
185#define NEIGH_UPDATE_F_ISROUTER 0x40000000
186#define NEIGH_UPDATE_F_ADMIN 0x80000000
187
188extern void neigh_table_init(struct neigh_table *tbl);
189extern void neigh_table_init_no_netlink(struct neigh_table *tbl);
190extern int neigh_table_clear(struct neigh_table *tbl);
191extern struct neighbour * neigh_lookup(struct neigh_table *tbl,
192 const void *pkey,
193 struct net_device *dev);
194extern struct neighbour * neigh_lookup_nodev(struct neigh_table *tbl,
195 struct net *net,
196 const void *pkey);
197extern struct neighbour * neigh_create(struct neigh_table *tbl,
198 const void *pkey,
199 struct net_device *dev);
200extern void neigh_destroy(struct neighbour *neigh);
201extern int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb);
202extern int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
203 u32 flags);
204extern void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev);
205extern int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev);
206extern int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb);
207extern int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb);
208extern int neigh_compat_output(struct neighbour *neigh, struct sk_buff *skb);
209extern int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb);
210extern struct neighbour *neigh_event_ns(struct neigh_table *tbl,
211 u8 *lladdr, void *saddr,
212 struct net_device *dev);
213
214extern struct neigh_parms *neigh_parms_alloc(struct net_device *dev, struct neigh_table *tbl);
215extern void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms);
216
217static inline
218struct net *neigh_parms_net(const struct neigh_parms *parms)
219{
220 return read_pnet(&parms->net);
221}
222
223extern unsigned long neigh_rand_reach_time(unsigned long base);
224
225extern void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
226 struct sk_buff *skb);
227extern struct pneigh_entry *pneigh_lookup(struct neigh_table *tbl, struct net *net, const void *key, struct net_device *dev, int creat);
228extern struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl,
229 struct net *net,
230 const void *key,
231 struct net_device *dev);
232extern int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *key, struct net_device *dev);
233
234static inline
235struct net *pneigh_net(const struct pneigh_entry *pneigh)
236{
237 return read_pnet(&pneigh->net);
238}
239
240extern void neigh_app_ns(struct neighbour *n);
241extern void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie);
242extern void __neigh_for_each_release(struct neigh_table *tbl, int (*cb)(struct neighbour *));
243extern void pneigh_for_each(struct neigh_table *tbl, void (*cb)(struct pneigh_entry *));
244
245struct neigh_seq_state {
246 struct seq_net_private p;
247 struct neigh_table *tbl;
248 struct neigh_hash_table *nht;
249 void *(*neigh_sub_iter)(struct neigh_seq_state *state,
250 struct neighbour *n, loff_t *pos);
251 unsigned int bucket;
252 unsigned int flags;
253#define NEIGH_SEQ_NEIGH_ONLY 0x00000001
254#define NEIGH_SEQ_IS_PNEIGH 0x00000002
255#define NEIGH_SEQ_SKIP_NOARP 0x00000004
256};
257extern void *neigh_seq_start(struct seq_file *, loff_t *, struct neigh_table *, unsigned int);
258extern void *neigh_seq_next(struct seq_file *, void *, loff_t *);
259extern void neigh_seq_stop(struct seq_file *, void *);
260
261extern int neigh_sysctl_register(struct net_device *dev,
262 struct neigh_parms *p,
263 char *p_name,
264 proc_handler *proc_handler);
265extern void neigh_sysctl_unregister(struct neigh_parms *p);
266
267static inline void __neigh_parms_put(struct neigh_parms *parms)
268{
269 atomic_dec(&parms->refcnt);
270}
271
272static inline struct neigh_parms *neigh_parms_clone(struct neigh_parms *parms)
273{
274 atomic_inc(&parms->refcnt);
275 return parms;
276}
277
278/*
279 * Neighbour references
280 */
281
282static inline void neigh_release(struct neighbour *neigh)
283{
284 if (atomic_dec_and_test(&neigh->refcnt))
285 neigh_destroy(neigh);
286}
287
288static inline struct neighbour * neigh_clone(struct neighbour *neigh)
289{
290 if (neigh)
291 atomic_inc(&neigh->refcnt);
292 return neigh;
293}
294
295#define neigh_hold(n) atomic_inc(&(n)->refcnt)
296
297static inline void neigh_confirm(struct neighbour *neigh)
298{
299 if (neigh)
300 neigh->confirmed = jiffies;
301}
302
303static inline int neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
304{
305 unsigned long now = jiffies;
306
307 if (neigh->used != now)
308 neigh->used = now;
309 if (!(neigh->nud_state&(NUD_CONNECTED|NUD_DELAY|NUD_PROBE)))
310 return __neigh_event_send(neigh, skb);
311 return 0;
312}
313
314#ifdef CONFIG_BRIDGE_NETFILTER
315static inline int neigh_hh_bridge(struct hh_cache *hh, struct sk_buff *skb)
316{
317 unsigned seq, hh_alen;
318
319 do {
320 seq = read_seqbegin(&hh->hh_lock);
321 hh_alen = HH_DATA_ALIGN(ETH_HLEN);
322 memcpy(skb->data - hh_alen, hh->hh_data, ETH_ALEN + hh_alen - ETH_HLEN);
323 } while (read_seqretry(&hh->hh_lock, seq));
324 return 0;
325}
326#endif
327
328static inline int neigh_hh_output(struct hh_cache *hh, struct sk_buff *skb)
329{
330 unsigned seq;
331 int hh_len;
332
333 do {
334 int hh_alen;
335
336 seq = read_seqbegin(&hh->hh_lock);
337 hh_len = hh->hh_len;
338 hh_alen = HH_DATA_ALIGN(hh_len);
339 memcpy(skb->data - hh_alen, hh->hh_data, hh_alen);
340 } while (read_seqretry(&hh->hh_lock, seq));
341
342 skb_push(skb, hh_len);
343 return dev_queue_xmit(skb);
344}
345
346static inline int neigh_output(struct neighbour *n, struct sk_buff *skb)
347{
348 struct hh_cache *hh = &n->hh;
349 if ((n->nud_state & NUD_CONNECTED) && hh->hh_len)
350 return neigh_hh_output(hh, skb);
351 else
352 return n->output(n, skb);
353}
354
355static inline struct neighbour *
356__neigh_lookup(struct neigh_table *tbl, const void *pkey, struct net_device *dev, int creat)
357{
358 struct neighbour *n = neigh_lookup(tbl, pkey, dev);
359
360 if (n || !creat)
361 return n;
362
363 n = neigh_create(tbl, pkey, dev);
364 return IS_ERR(n) ? NULL : n;
365}
366
367static inline struct neighbour *
368__neigh_lookup_errno(struct neigh_table *tbl, const void *pkey,
369 struct net_device *dev)
370{
371 struct neighbour *n = neigh_lookup(tbl, pkey, dev);
372
373 if (n)
374 return n;
375
376 return neigh_create(tbl, pkey, dev);
377}
378
379struct neighbour_cb {
380 unsigned long sched_next;
381 unsigned int flags;
382};
383
384#define LOCALLY_ENQUEUED 0x1
385
386#define NEIGH_CB(skb) ((struct neighbour_cb *)(skb)->cb)
387
388static inline void neigh_ha_snapshot(char *dst, const struct neighbour *n,
389 const struct net_device *dev)
390{
391 unsigned int seq;
392
393 do {
394 seq = read_seqbegin(&n->ha_lock);
395 memcpy(dst, n->ha, dev->addr_len);
396 } while (read_seqretry(&n->ha_lock, seq));
397}
398#endif