neighbour.h 12.5 KB
Newer Older
L
Linus Torvalds 已提交
1 2 3
#ifndef _NET_NEIGHBOUR_H
#define _NET_NEIGHBOUR_H

4 5
#include <linux/neighbour.h>

L
Linus Torvalds 已提交
6 7 8 9 10 11 12 13 14 15 16 17 18
/*
 *	Generic neighbour manipulation
 *
 *	Authors:
 *	Pedro Roque		<roque@di.fc.ul.pt>
 *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
 *
 * 	Changes:
 *
 *	Harald Welte:		<laforge@gnumonks.org>
 *		- Add neighbour cache statistics like rtstat
 */

19
#include <linux/atomic.h>
L
Linus Torvalds 已提交
20
#include <linux/netdevice.h>
21
#include <linux/skbuff.h>
L
Linus Torvalds 已提交
22 23
#include <linux/rcupdate.h>
#include <linux/seq_file.h>
24
#include <linux/bitmap.h>
L
Linus Torvalds 已提交
25 26 27

#include <linux/err.h>
#include <linux/sysctl.h>
28
#include <linux/workqueue.h>
29
#include <net/rtnetlink.h>
L
Linus Torvalds 已提交
30

31 32 33 34
/*
 * NUD stands for "neighbor unreachability detection"
 */

L
Linus Torvalds 已提交
35 36 37 38 39 40
#define NUD_IN_TIMER	(NUD_INCOMPLETE|NUD_REACHABLE|NUD_DELAY|NUD_PROBE)
#define NUD_VALID	(NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE|NUD_PROBE|NUD_STALE|NUD_DELAY)
#define NUD_CONNECTED	(NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE)

struct neighbour;

41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66
enum {
	NEIGH_VAR_MCAST_PROBES,
	NEIGH_VAR_UCAST_PROBES,
	NEIGH_VAR_APP_PROBES,
	NEIGH_VAR_RETRANS_TIME,
	NEIGH_VAR_BASE_REACHABLE_TIME,
	NEIGH_VAR_DELAY_PROBE_TIME,
	NEIGH_VAR_GC_STALETIME,
	NEIGH_VAR_QUEUE_LEN_BYTES,
	NEIGH_VAR_PROXY_QLEN,
	NEIGH_VAR_ANYCAST_DELAY,
	NEIGH_VAR_PROXY_DELAY,
	NEIGH_VAR_LOCKTIME,
#define NEIGH_VAR_DATA_MAX (NEIGH_VAR_LOCKTIME + 1)
	/* Following are used as a second way to access one of the above */
	NEIGH_VAR_QUEUE_LEN, /* same data as NEIGH_VAR_QUEUE_LEN_BYTES */
	NEIGH_VAR_RETRANS_TIME_MS, /* same data as NEIGH_VAR_RETRANS_TIME */
	NEIGH_VAR_BASE_REACHABLE_TIME_MS, /* same data as NEIGH_VAR_BASE_REACHABLE_TIME */
	/* Following are used by "default" only */
	NEIGH_VAR_GC_INTERVAL,
	NEIGH_VAR_GC_THRESH1,
	NEIGH_VAR_GC_THRESH2,
	NEIGH_VAR_GC_THRESH3,
	NEIGH_VAR_MAX
};

E
Eric Dumazet 已提交
67
struct neigh_parms {
68
#ifdef CONFIG_NET_NS
69
	struct net *net;
70
#endif
71
	struct net_device *dev;
72
	struct list_head list;
73
	int	(*neigh_setup)(struct neighbour *);
74
	void	(*neigh_cleanup)(struct neighbour *);
L
Linus Torvalds 已提交
75 76 77 78 79 80 81 82 83
	struct neigh_table *tbl;

	void	*sysctl_table;

	int dead;
	atomic_t refcnt;
	struct rcu_head rcu_head;

	int	reachable_time;
84
	int	data[NEIGH_VAR_DATA_MAX];
85
	DECLARE_BITMAP(data_state, NEIGH_VAR_DATA_MAX);
L
Linus Torvalds 已提交
86 87
};

88 89
static inline void neigh_var_set(struct neigh_parms *p, int index, int val)
{
90
	set_bit(index, p->data_state);
91 92 93 94
	p->data[index] = val;
}

#define NEIGH_VAR(p, attr) ((p)->data[NEIGH_VAR_ ## attr])
95 96 97 98 99

/* In ndo_neigh_setup, NEIGH_VAR_INIT should be used.
 * In other cases, NEIGH_VAR_SET should be used.
 */
#define NEIGH_VAR_INIT(p, attr, val) (NEIGH_VAR(p, attr) = val)
100 101
#define NEIGH_VAR_SET(p, attr, val) neigh_var_set(p, NEIGH_VAR_ ## attr, val)

102 103 104 105 106 107 108 109 110 111
static inline void neigh_parms_data_state_setall(struct neigh_parms *p)
{
	bitmap_fill(p->data_state, NEIGH_VAR_DATA_MAX);
}

static inline void neigh_parms_data_state_cleanall(struct neigh_parms *p)
{
	bitmap_zero(p->data_state, NEIGH_VAR_DATA_MAX);
}

E
Eric Dumazet 已提交
112
struct neigh_statistics {
L
Linus Torvalds 已提交
113 114 115 116
	unsigned long allocs;		/* number of allocated neighs */
	unsigned long destroys;		/* number of destroyed neighs */
	unsigned long hash_grows;	/* number of hash resizes */

117
	unsigned long res_failed;	/* number of failed resolutions */
L
Linus Torvalds 已提交
118 119 120 121 122 123 124 125 126

	unsigned long lookups;		/* number of lookups */
	unsigned long hits;		/* number of hits (among lookups) */

	unsigned long rcv_probes_mcast;	/* number of received mcast ipv6 */
	unsigned long rcv_probes_ucast; /* number of received ucast ipv6 */

	unsigned long periodic_gc_runs;	/* number of periodic GC runs */
	unsigned long forced_gc_runs;	/* number of forced GC runs */
127 128

	unsigned long unres_discards;	/* number of unresolved drops */
L
Linus Torvalds 已提交
129 130
};

131
#define NEIGH_CACHE_STAT_INC(tbl, field) this_cpu_inc((tbl)->stats->field)
L
Linus Torvalds 已提交
132

E
Eric Dumazet 已提交
133
struct neighbour {
134
	struct neighbour __rcu	*next;
L
Linus Torvalds 已提交
135 136 137 138
	struct neigh_table	*tbl;
	struct neigh_parms	*parms;
	unsigned long		confirmed;
	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;
143 144
	struct timer_list	timer;
	unsigned long		used;
L
Linus Torvalds 已提交
145
	atomic_t		probes;
146 147 148 149
	__u8			flags;
	__u8			nud_state;
	__u8			type;
	__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;
L
Linus Torvalds 已提交
157 158 159
	u8			primary_key[0];
};

E
Eric Dumazet 已提交
160
struct neigh_ops {
L
Linus Torvalds 已提交
161
	int			family;
162 163 164 165
	void			(*solicit)(struct neighbour *, struct sk_buff *);
	void			(*error_report)(struct neighbour *, struct sk_buff *);
	int			(*output)(struct neighbour *, struct sk_buff *);
	int			(*connected_output)(struct neighbour *, struct sk_buff *);
L
Linus Torvalds 已提交
166 167
};

E
Eric Dumazet 已提交
168
struct pneigh_entry {
L
Linus Torvalds 已提交
169
	struct pneigh_entry	*next;
170
#ifdef CONFIG_NET_NS
171
	struct net		*net;
172
#endif
173
	struct net_device	*dev;
174
	u8			flags;
L
Linus Torvalds 已提交
175 176 177 178 179 180 181
	u8			key[0];
};

/*
 *	neighbour table manipulation
 */

182 183
#define NEIGH_NUM_HASH_RND	4

184
struct neigh_hash_table {
185
	struct neighbour __rcu	**hash_buckets;
186
	unsigned int		hash_shift;
187
	__u32			hash_rnd[NEIGH_NUM_HASH_RND];
188 189 190
	struct rcu_head		rcu;
};

L
Linus Torvalds 已提交
191

E
Eric Dumazet 已提交
192
struct neigh_table {
L
Linus Torvalds 已提交
193 194 195 196
	struct neigh_table	*next;
	int			family;
	int			entry_size;
	int			key_len;
197 198
	__u32			(*hash)(const void *pkey,
					const struct net_device *dev,
199
					__u32 *hash_rnd);
L
Linus Torvalds 已提交
200 201 202 203 204 205
	int			(*constructor)(struct neighbour *);
	int			(*pconstructor)(struct pneigh_entry *);
	void			(*pdestructor)(struct pneigh_entry *);
	void			(*proxy_redo)(struct sk_buff *skb);
	char			*id;
	struct neigh_parms	parms;
206
	struct list_head	parms_list;
L
Linus Torvalds 已提交
207 208 209 210 211
	int			gc_interval;
	int			gc_thresh1;
	int			gc_thresh2;
	int			gc_thresh3;
	unsigned long		last_flush;
212
	struct delayed_work	gc_work;
L
Linus Torvalds 已提交
213 214 215 216 217
	struct timer_list 	proxy_timer;
	struct sk_buff_head	proxy_queue;
	atomic_t		entries;
	rwlock_t		lock;
	unsigned long		last_rand;
218
	struct neigh_statistics	__percpu *stats;
219
	struct neigh_hash_table __rcu *nht;
L
Linus Torvalds 已提交
220 221 222
	struct pneigh_entry	**phash_buckets;
};

223 224 225 226 227
static inline int neigh_parms_family(struct neigh_parms *p)
{
	return p->tbl->family;
}

228
#define NEIGH_PRIV_ALIGN	sizeof(long long)
229
#define NEIGH_ENTRY_SIZE(size)	ALIGN((size), NEIGH_PRIV_ALIGN)
230 231 232

static inline void *neighbour_priv(const struct neighbour *n)
{
233
	return (char *)n + n->tbl->entry_size;
234 235
}

L
Linus Torvalds 已提交
236 237 238 239 240 241 242
/* flags for neigh_update() */
#define NEIGH_UPDATE_F_OVERRIDE			0x00000001
#define NEIGH_UPDATE_F_WEAK_OVERRIDE		0x00000002
#define NEIGH_UPDATE_F_OVERRIDE_ISROUTER	0x00000004
#define NEIGH_UPDATE_F_ISROUTER			0x40000000
#define NEIGH_UPDATE_F_ADMIN			0x80000000

243 244 245 246 247 248 249 250
void neigh_table_init(struct neigh_table *tbl);
int neigh_table_clear(struct neigh_table *tbl);
struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
			       struct net_device *dev);
struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net,
				     const void *pkey);
struct neighbour *__neigh_create(struct neigh_table *tbl, const void *pkey,
				 struct net_device *dev, bool want_ref);
251
static inline struct neighbour *neigh_create(struct neigh_table *tbl,
L
Linus Torvalds 已提交
252
					     const void *pkey,
253 254 255 256
					     struct net_device *dev)
{
	return __neigh_create(tbl, pkey, dev, true);
}
257 258 259
void neigh_destroy(struct neighbour *neigh);
int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb);
int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new, u32 flags);
260
void __neigh_set_probe_once(struct neighbour *neigh);
261 262 263 264 265 266 267
void neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev);
int neigh_ifdown(struct neigh_table *tbl, struct net_device *dev);
int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb);
int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb);
int neigh_compat_output(struct neighbour *neigh, struct sk_buff *skb);
int neigh_direct_output(struct neighbour *neigh, struct sk_buff *skb);
struct neighbour *neigh_event_ns(struct neigh_table *tbl,
L
Linus Torvalds 已提交
268 269 270
						u8 *lladdr, void *saddr,
						struct net_device *dev);

271 272 273
struct neigh_parms *neigh_parms_alloc(struct net_device *dev,
				      struct neigh_table *tbl);
void neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms);
274 275

static inline
276
struct net *neigh_parms_net(const struct neigh_parms *parms)
277
{
278
	return read_pnet(&parms->net);
279 280
}

281
unsigned long neigh_rand_reach_time(unsigned long base);
L
Linus Torvalds 已提交
282

283 284 285 286 287 288 289 290 291
void pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
		    struct sk_buff *skb);
struct pneigh_entry *pneigh_lookup(struct neigh_table *tbl, struct net *net,
				   const void *key, struct net_device *dev,
				   int creat);
struct pneigh_entry *__pneigh_lookup(struct neigh_table *tbl, struct net *net,
				     const void *key, struct net_device *dev);
int pneigh_delete(struct neigh_table *tbl, struct net *net, const void *key,
		  struct net_device *dev);
L
Linus Torvalds 已提交
292

293
static inline struct net *pneigh_net(const struct pneigh_entry *pneigh)
294
{
295
	return read_pnet(&pneigh->net);
296 297
}

298 299 300 301 302 303 304
void neigh_app_ns(struct neighbour *n);
void neigh_for_each(struct neigh_table *tbl,
		    void (*cb)(struct neighbour *, void *), void *cookie);
void __neigh_for_each_release(struct neigh_table *tbl,
			      int (*cb)(struct neighbour *));
void pneigh_for_each(struct neigh_table *tbl,
		     void (*cb)(struct pneigh_entry *));
L
Linus Torvalds 已提交
305 306

struct neigh_seq_state {
307
	struct seq_net_private p;
L
Linus Torvalds 已提交
308
	struct neigh_table *tbl;
309
	struct neigh_hash_table *nht;
L
Linus Torvalds 已提交
310 311 312 313 314 315 316 317
	void *(*neigh_sub_iter)(struct neigh_seq_state *state,
				struct neighbour *n, loff_t *pos);
	unsigned int bucket;
	unsigned int flags;
#define NEIGH_SEQ_NEIGH_ONLY	0x00000001
#define NEIGH_SEQ_IS_PNEIGH	0x00000002
#define NEIGH_SEQ_SKIP_NOARP	0x00000004
};
318 319 320 321 322
void *neigh_seq_start(struct seq_file *, loff_t *, struct neigh_table *,
		      unsigned int);
void *neigh_seq_next(struct seq_file *, void *, loff_t *);
void neigh_seq_stop(struct seq_file *, void *);

323 324 325 326 327 328 329 330 331
int neigh_proc_dointvec(struct ctl_table *ctl, int write,
			void __user *buffer, size_t *lenp, loff_t *ppos);
int neigh_proc_dointvec_jiffies(struct ctl_table *ctl, int write,
				void __user *buffer,
				size_t *lenp, loff_t *ppos);
int neigh_proc_dointvec_ms_jiffies(struct ctl_table *ctl, int write,
				   void __user *buffer,
				   size_t *lenp, loff_t *ppos);

332
int neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
333
			  proc_handler *proc_handler);
334
void neigh_sysctl_unregister(struct neigh_parms *p);
L
Linus Torvalds 已提交
335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367

static inline void __neigh_parms_put(struct neigh_parms *parms)
{
	atomic_dec(&parms->refcnt);
}

static inline struct neigh_parms *neigh_parms_clone(struct neigh_parms *parms)
{
	atomic_inc(&parms->refcnt);
	return parms;
}

/*
 *	Neighbour references
 */

static inline void neigh_release(struct neighbour *neigh)
{
	if (atomic_dec_and_test(&neigh->refcnt))
		neigh_destroy(neigh);
}

static inline struct neighbour * neigh_clone(struct neighbour *neigh)
{
	if (neigh)
		atomic_inc(&neigh->refcnt);
	return neigh;
}

#define neigh_hold(n)	atomic_inc(&(n)->refcnt)

static inline int neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
{
368
	unsigned long now = jiffies;
369 370 371
	
	if (neigh->used != now)
		neigh->used = now;
L
Linus Torvalds 已提交
372 373 374 375 376
	if (!(neigh->nud_state&(NUD_CONNECTED|NUD_DELAY|NUD_PROBE)))
		return __neigh_event_send(neigh, skb);
	return 0;
}

377
#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
378 379
static inline int neigh_hh_bridge(struct hh_cache *hh, struct sk_buff *skb)
{
380
	unsigned int seq, hh_alen;
381 382 383 384 385 386 387 388 389 390

	do {
		seq = read_seqbegin(&hh->hh_lock);
		hh_alen = HH_DATA_ALIGN(ETH_HLEN);
		memcpy(skb->data - hh_alen, hh->hh_data, ETH_ALEN + hh_alen - ETH_HLEN);
	} while (read_seqretry(&hh->hh_lock, seq));
	return 0;
}
#endif

391
static inline int neigh_hh_output(const struct hh_cache *hh, struct sk_buff *skb)
392
{
393
	unsigned int seq;
394 395 396 397 398
	int hh_len;

	do {
		seq = read_seqbegin(&hh->hh_lock);
		hh_len = hh->hh_len;
399 400 401 402 403 404 405 406
		if (likely(hh_len <= HH_DATA_MOD)) {
			/* this is inlined by gcc */
			memcpy(skb->data - HH_DATA_MOD, hh->hh_data, HH_DATA_MOD);
		} else {
			int hh_alen = HH_DATA_ALIGN(hh_len);

			memcpy(skb->data - hh_alen, hh->hh_data, hh_alen);
		}
407 408 409
	} while (read_seqretry(&hh->hh_lock, seq));

	skb_push(skb, hh_len);
410
	return dev_queue_xmit(skb);
411 412
}

L
Linus Torvalds 已提交
413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436
static inline struct neighbour *
__neigh_lookup(struct neigh_table *tbl, const void *pkey, struct net_device *dev, int creat)
{
	struct neighbour *n = neigh_lookup(tbl, pkey, dev);

	if (n || !creat)
		return n;

	n = neigh_create(tbl, pkey, dev);
	return IS_ERR(n) ? NULL : n;
}

static inline struct neighbour *
__neigh_lookup_errno(struct neigh_table *tbl, const void *pkey,
  struct net_device *dev)
{
	struct neighbour *n = neigh_lookup(tbl, pkey, dev);

	if (n)
		return n;

	return neigh_create(tbl, pkey, dev);
}

437 438 439 440 441 442 443 444
struct neighbour_cb {
	unsigned long sched_next;
	unsigned int flags;
};

#define LOCALLY_ENQUEUED 0x1

#define NEIGH_CB(skb)	((struct neighbour_cb *)(skb)->cb)
L
Linus Torvalds 已提交
445

446 447 448 449 450 451 452 453 454 455
static inline void neigh_ha_snapshot(char *dst, const struct neighbour *n,
				     const struct net_device *dev)
{
	unsigned int seq;

	do {
		seq = read_seqbegin(&n->ha_lock);
		memcpy(dst, n->ha, dev->addr_len);
	} while (read_seqretry(&n->ha_lock, seq));
}
L
Linus Torvalds 已提交
456
#endif
新手
引导
客服 返回
顶部