xref: /openbmc/linux/include/net/neighbour.h (revision 64c70b1c)
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 <asm/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 <net/rtnetlink.h>
28 
29 #define NUD_IN_TIMER	(NUD_INCOMPLETE|NUD_REACHABLE|NUD_DELAY|NUD_PROBE)
30 #define NUD_VALID	(NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE|NUD_PROBE|NUD_STALE|NUD_DELAY)
31 #define NUD_CONNECTED	(NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE)
32 
33 struct neighbour;
34 
35 struct neigh_parms
36 {
37 	struct net_device *dev;
38 	struct neigh_parms *next;
39 	int	(*neigh_setup)(struct neighbour *);
40 	void	(*neigh_cleanup)(struct neighbour *);
41 	struct neigh_table *tbl;
42 
43 	void	*sysctl_table;
44 
45 	int dead;
46 	atomic_t refcnt;
47 	struct rcu_head rcu_head;
48 
49 	int	base_reachable_time;
50 	int	retrans_time;
51 	int	gc_staletime;
52 	int	reachable_time;
53 	int	delay_probe_time;
54 
55 	int	queue_len;
56 	int	ucast_probes;
57 	int	app_probes;
58 	int	mcast_probes;
59 	int	anycast_delay;
60 	int	proxy_delay;
61 	int	proxy_qlen;
62 	int	locktime;
63 };
64 
65 struct neigh_statistics
66 {
67 	unsigned long allocs;		/* number of allocated neighs */
68 	unsigned long destroys;		/* number of destroyed neighs */
69 	unsigned long hash_grows;	/* number of hash resizes */
70 
71 	unsigned long res_failed;	/* nomber of failed resolutions */
72 
73 	unsigned long lookups;		/* number of lookups */
74 	unsigned long hits;		/* number of hits (among lookups) */
75 
76 	unsigned long rcv_probes_mcast;	/* number of received mcast ipv6 */
77 	unsigned long rcv_probes_ucast; /* number of received ucast ipv6 */
78 
79 	unsigned long periodic_gc_runs;	/* number of periodic GC runs */
80 	unsigned long forced_gc_runs;	/* number of forced GC runs */
81 };
82 
83 #define NEIGH_CACHE_STAT_INC(tbl, field)				\
84 	do {								\
85 		preempt_disable();					\
86 		(per_cpu_ptr((tbl)->stats, smp_processor_id())->field)++; \
87 		preempt_enable();					\
88 	} while (0)
89 
90 struct neighbour
91 {
92 	struct neighbour	*next;
93 	struct neigh_table	*tbl;
94 	struct neigh_parms	*parms;
95 	struct net_device		*dev;
96 	unsigned long		used;
97 	unsigned long		confirmed;
98 	unsigned long		updated;
99 	__u8			flags;
100 	__u8			nud_state;
101 	__u8			type;
102 	__u8			dead;
103 	atomic_t		probes;
104 	rwlock_t		lock;
105 	unsigned char		ha[ALIGN(MAX_ADDR_LEN, sizeof(unsigned long))];
106 	struct hh_cache		*hh;
107 	atomic_t		refcnt;
108 	int			(*output)(struct sk_buff *skb);
109 	struct sk_buff_head	arp_queue;
110 	struct timer_list	timer;
111 	struct neigh_ops	*ops;
112 	u8			primary_key[0];
113 };
114 
115 struct neigh_ops
116 {
117 	int			family;
118 	void			(*solicit)(struct neighbour *, struct sk_buff*);
119 	void			(*error_report)(struct neighbour *, struct sk_buff*);
120 	int			(*output)(struct sk_buff*);
121 	int			(*connected_output)(struct sk_buff*);
122 	int			(*hh_output)(struct sk_buff*);
123 	int			(*queue_xmit)(struct sk_buff*);
124 };
125 
126 struct pneigh_entry
127 {
128 	struct pneigh_entry	*next;
129 	struct net_device		*dev;
130 	u8			flags;
131 	u8			key[0];
132 };
133 
134 /*
135  *	neighbour table manipulation
136  */
137 
138 
139 struct neigh_table
140 {
141 	struct neigh_table	*next;
142 	int			family;
143 	int			entry_size;
144 	int			key_len;
145 	__u32			(*hash)(const void *pkey, const struct net_device *);
146 	int			(*constructor)(struct neighbour *);
147 	int			(*pconstructor)(struct pneigh_entry *);
148 	void			(*pdestructor)(struct pneigh_entry *);
149 	void			(*proxy_redo)(struct sk_buff *skb);
150 	char			*id;
151 	struct neigh_parms	parms;
152 	/* HACK. gc_* shoul follow parms without a gap! */
153 	int			gc_interval;
154 	int			gc_thresh1;
155 	int			gc_thresh2;
156 	int			gc_thresh3;
157 	unsigned long		last_flush;
158 	struct timer_list 	gc_timer;
159 	struct timer_list 	proxy_timer;
160 	struct sk_buff_head	proxy_queue;
161 	atomic_t		entries;
162 	rwlock_t		lock;
163 	unsigned long		last_rand;
164 	struct kmem_cache		*kmem_cachep;
165 	struct neigh_statistics	*stats;
166 	struct neighbour	**hash_buckets;
167 	unsigned int		hash_mask;
168 	__u32			hash_rnd;
169 	unsigned int		hash_chain_gc;
170 	struct pneigh_entry	**phash_buckets;
171 #ifdef CONFIG_PROC_FS
172 	struct proc_dir_entry	*pde;
173 #endif
174 };
175 
176 /* flags for neigh_update() */
177 #define NEIGH_UPDATE_F_OVERRIDE			0x00000001
178 #define NEIGH_UPDATE_F_WEAK_OVERRIDE		0x00000002
179 #define NEIGH_UPDATE_F_OVERRIDE_ISROUTER	0x00000004
180 #define NEIGH_UPDATE_F_ISROUTER			0x40000000
181 #define NEIGH_UPDATE_F_ADMIN			0x80000000
182 
183 extern void			neigh_table_init(struct neigh_table *tbl);
184 extern void			neigh_table_init_no_netlink(struct neigh_table *tbl);
185 extern int			neigh_table_clear(struct neigh_table *tbl);
186 extern struct neighbour *	neigh_lookup(struct neigh_table *tbl,
187 					     const void *pkey,
188 					     struct net_device *dev);
189 extern struct neighbour *	neigh_lookup_nodev(struct neigh_table *tbl,
190 						   const void *pkey);
191 extern struct neighbour *	neigh_create(struct neigh_table *tbl,
192 					     const void *pkey,
193 					     struct net_device *dev);
194 extern void			neigh_destroy(struct neighbour *neigh);
195 extern int			__neigh_event_send(struct neighbour *neigh, struct sk_buff *skb);
196 extern int			neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
197 					     u32 flags);
198 extern void			neigh_changeaddr(struct neigh_table *tbl, struct net_device *dev);
199 extern int			neigh_ifdown(struct neigh_table *tbl, struct net_device *dev);
200 extern int			neigh_resolve_output(struct sk_buff *skb);
201 extern int			neigh_connected_output(struct sk_buff *skb);
202 extern int			neigh_compat_output(struct sk_buff *skb);
203 extern struct neighbour 	*neigh_event_ns(struct neigh_table *tbl,
204 						u8 *lladdr, void *saddr,
205 						struct net_device *dev);
206 
207 extern struct neigh_parms	*neigh_parms_alloc(struct net_device *dev, struct neigh_table *tbl);
208 extern void			neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms);
209 extern void			neigh_parms_destroy(struct neigh_parms *parms);
210 extern unsigned long		neigh_rand_reach_time(unsigned long base);
211 
212 extern void			pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
213 					       struct sk_buff *skb);
214 extern struct pneigh_entry	*pneigh_lookup(struct neigh_table *tbl, const void *key, struct net_device *dev, int creat);
215 extern int			pneigh_delete(struct neigh_table *tbl, const void *key, struct net_device *dev);
216 
217 extern void neigh_app_ns(struct neighbour *n);
218 extern void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie);
219 extern void __neigh_for_each_release(struct neigh_table *tbl, int (*cb)(struct neighbour *));
220 extern void pneigh_for_each(struct neigh_table *tbl, void (*cb)(struct pneigh_entry *));
221 
222 struct neigh_seq_state {
223 	struct neigh_table *tbl;
224 	void *(*neigh_sub_iter)(struct neigh_seq_state *state,
225 				struct neighbour *n, loff_t *pos);
226 	unsigned int bucket;
227 	unsigned int flags;
228 #define NEIGH_SEQ_NEIGH_ONLY	0x00000001
229 #define NEIGH_SEQ_IS_PNEIGH	0x00000002
230 #define NEIGH_SEQ_SKIP_NOARP	0x00000004
231 };
232 extern void *neigh_seq_start(struct seq_file *, loff_t *, struct neigh_table *, unsigned int);
233 extern void *neigh_seq_next(struct seq_file *, void *, loff_t *);
234 extern void neigh_seq_stop(struct seq_file *, void *);
235 
236 extern int			neigh_sysctl_register(struct net_device *dev,
237 						      struct neigh_parms *p,
238 						      int p_id, int pdev_id,
239 						      char *p_name,
240 						      proc_handler *proc_handler,
241 						      ctl_handler *strategy);
242 extern void			neigh_sysctl_unregister(struct neigh_parms *p);
243 
244 static inline void __neigh_parms_put(struct neigh_parms *parms)
245 {
246 	atomic_dec(&parms->refcnt);
247 }
248 
249 static inline void neigh_parms_put(struct neigh_parms *parms)
250 {
251 	if (atomic_dec_and_test(&parms->refcnt))
252 		neigh_parms_destroy(parms);
253 }
254 
255 static inline struct neigh_parms *neigh_parms_clone(struct neigh_parms *parms)
256 {
257 	atomic_inc(&parms->refcnt);
258 	return parms;
259 }
260 
261 /*
262  *	Neighbour references
263  */
264 
265 static inline void neigh_release(struct neighbour *neigh)
266 {
267 	if (atomic_dec_and_test(&neigh->refcnt))
268 		neigh_destroy(neigh);
269 }
270 
271 static inline struct neighbour * neigh_clone(struct neighbour *neigh)
272 {
273 	if (neigh)
274 		atomic_inc(&neigh->refcnt);
275 	return neigh;
276 }
277 
278 #define neigh_hold(n)	atomic_inc(&(n)->refcnt)
279 
280 static inline void neigh_confirm(struct neighbour *neigh)
281 {
282 	if (neigh)
283 		neigh->confirmed = jiffies;
284 }
285 
286 static inline int neigh_is_connected(struct neighbour *neigh)
287 {
288 	return neigh->nud_state&NUD_CONNECTED;
289 }
290 
291 static inline int neigh_is_valid(struct neighbour *neigh)
292 {
293 	return neigh->nud_state&NUD_VALID;
294 }
295 
296 static inline int neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
297 {
298 	neigh->used = jiffies;
299 	if (!(neigh->nud_state&(NUD_CONNECTED|NUD_DELAY|NUD_PROBE)))
300 		return __neigh_event_send(neigh, skb);
301 	return 0;
302 }
303 
304 static inline int neigh_hh_output(struct hh_cache *hh, struct sk_buff *skb)
305 {
306 	unsigned seq;
307 	int hh_len;
308 
309 	do {
310 		int hh_alen;
311 
312 		seq = read_seqbegin(&hh->hh_lock);
313 		hh_len = hh->hh_len;
314 		hh_alen = HH_DATA_ALIGN(hh_len);
315 		memcpy(skb->data - hh_alen, hh->hh_data, hh_alen);
316 	} while (read_seqretry(&hh->hh_lock, seq));
317 
318 	skb_push(skb, hh_len);
319 	return hh->hh_output(skb);
320 }
321 
322 static inline struct neighbour *
323 __neigh_lookup(struct neigh_table *tbl, const void *pkey, struct net_device *dev, int creat)
324 {
325 	struct neighbour *n = neigh_lookup(tbl, pkey, dev);
326 
327 	if (n || !creat)
328 		return n;
329 
330 	n = neigh_create(tbl, pkey, dev);
331 	return IS_ERR(n) ? NULL : n;
332 }
333 
334 static inline struct neighbour *
335 __neigh_lookup_errno(struct neigh_table *tbl, const void *pkey,
336   struct net_device *dev)
337 {
338 	struct neighbour *n = neigh_lookup(tbl, pkey, dev);
339 
340 	if (n)
341 		return n;
342 
343 	return neigh_create(tbl, pkey, dev);
344 }
345 
346 struct neighbour_cb {
347 	unsigned long sched_next;
348 	unsigned int flags;
349 };
350 
351 #define LOCALLY_ENQUEUED 0x1
352 
353 #define NEIGH_CB(skb)	((struct neighbour_cb *)(skb)->cb)
354 
355 #endif
356