1#ifndef _NET_NEIGHBOUR_H
2#define _NET_NEIGHBOUR_H
3
4/*
5 *	Generic neighbour manipulation
6 *
7 *	Authors:
8 *	Pedro Roque		<roque@di.fc.ul.pt>
9 *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
10 */
11
12/* The following flags & states are exported to user space,
13   so that they should be moved to include/linux/ directory.
14 */
15
16/*
17 *	Neighbor Cache Entry Flags
18 */
19
20#define NTF_PROXY	0x08	/* == ATF_PUBL */
21#define NTF_ROUTER	0x80
22
23/*
24 *	Neighbor Cache Entry States.
25 */
26
27#define NUD_INCOMPLETE	0x01
28#define NUD_REACHABLE	0x02
29#define NUD_STALE	0x04
30#define NUD_DELAY	0x08
31#define NUD_PROBE	0x10
32#define NUD_FAILED	0x20
33
34/* Dummy states */
35#define NUD_NOARP	0x40
36#define NUD_PERMANENT	0x80
37#define NUD_NONE	0x00
38
39/* NUD_NOARP & NUD_PERMANENT are pseudostates, they never change
40   and make no address resolution or NUD.
41   NUD_PERMANENT is also cannot be deleted by garbage collectors.
42 */
43
44#ifdef __KERNEL__
45
46#include <asm/atomic.h>
47#include <linux/skbuff.h>
48
49#define NUD_IN_TIMER	(NUD_INCOMPLETE|NUD_DELAY|NUD_PROBE)
50#define NUD_VALID	(NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE|NUD_PROBE|NUD_STALE|NUD_DELAY)
51#define NUD_CONNECTED	(NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE)
52
53struct neigh_parms
54{
55	struct neigh_parms *next;
56	int	(*neigh_setup)(struct neighbour *);
57	struct neigh_table *tbl;
58	int	entries;
59	void	*priv;
60
61	void	*sysctl_table;
62
63	int	base_reachable_time;
64	int	retrans_time;
65	int	gc_staletime;
66	int	reachable_time;
67	int	delay_probe_time;
68
69	int	queue_len;
70	int	ucast_probes;
71	int	app_probes;
72	int	mcast_probes;
73	int	anycast_delay;
74	int	proxy_delay;
75	int	proxy_qlen;
76	int	locktime;
77};
78
79struct neigh_statistics
80{
81	unsigned long allocs;
82	unsigned long res_failed;
83	unsigned long rcv_probes_mcast;
84	unsigned long rcv_probes_ucast;
85};
86
87struct neighbour
88{
89	struct neighbour	*next;
90	struct neigh_table	*tbl;
91	struct neigh_parms	*parms;
92	struct net_device		*dev;
93	unsigned long		used;
94	unsigned long		confirmed;
95	unsigned long		updated;
96	__u8			flags;
97	__u8			nud_state;
98	__u8			type;
99	__u8			dead;
100	atomic_t		probes;
101	rwlock_t		lock;
102	unsigned char		ha[(MAX_ADDR_LEN+sizeof(unsigned long)-1)&~(sizeof(unsigned long)-1)];
103	struct hh_cache		*hh;
104	atomic_t		refcnt;
105	int			(*output)(struct sk_buff *skb);
106	struct sk_buff_head	arp_queue;
107	struct timer_list	timer;
108	struct neigh_ops	*ops;
109	u8			primary_key[0];
110};
111
112struct neigh_ops
113{
114	int			family;
115	void			(*destructor)(struct neighbour *);
116	void			(*solicit)(struct neighbour *, struct sk_buff*);
117	void			(*error_report)(struct neighbour *, struct sk_buff*);
118	int			(*output)(struct sk_buff*);
119	int			(*connected_output)(struct sk_buff*);
120	int			(*hh_output)(struct sk_buff*);
121	int			(*queue_xmit)(struct sk_buff*);
122};
123
124struct pneigh_entry
125{
126	struct pneigh_entry	*next;
127	struct net_device		*dev;
128	u8			key[0];
129};
130
131#define NEIGH_HASHMASK		0x1F
132#define PNEIGH_HASHMASK		0xF
133
134/*
135 *	neighbour table manipulation
136 */
137
138
139struct 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	int			entries;
162	rwlock_t		lock;
163	unsigned long		last_rand;
164	struct neigh_parms	*parms_list;
165	kmem_cache_t		*kmem_cachep;
166	struct tasklet_struct	gc_task;
167	struct neigh_statistics	stats;
168	struct neighbour	*hash_buckets[NEIGH_HASHMASK+1];
169	struct pneigh_entry	*phash_buckets[PNEIGH_HASHMASK+1];
170};
171
172extern void			neigh_table_init(struct neigh_table *tbl);
173extern int			neigh_table_clear(struct neigh_table *tbl);
174extern struct neighbour *	neigh_lookup(struct neigh_table *tbl,
175					     const void *pkey,
176					     struct net_device *dev);
177extern struct neighbour *	neigh_create(struct neigh_table *tbl,
178					     const void *pkey,
179					     struct net_device *dev);
180extern void			neigh_destroy(struct neighbour *neigh);
181extern int			__neigh_event_send(struct neighbour *neigh, struct sk_buff *skb);
182extern int			neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new, int override, int arp);
183extern int			neigh_ifdown(struct neigh_table *tbl, struct net_device *dev);
184extern int			neigh_resolve_output(struct sk_buff *skb);
185extern int			neigh_connected_output(struct sk_buff *skb);
186extern int			neigh_compat_output(struct sk_buff *skb);
187extern struct neighbour 	*neigh_event_ns(struct neigh_table *tbl,
188						u8 *lladdr, void *saddr,
189						struct net_device *dev);
190
191extern struct neigh_parms	*neigh_parms_alloc(struct net_device *dev, struct neigh_table *tbl);
192extern void			neigh_parms_release(struct neigh_table *tbl, struct neigh_parms *parms);
193extern unsigned long		neigh_rand_reach_time(unsigned long base);
194
195extern void			pneigh_enqueue(struct neigh_table *tbl, struct neigh_parms *p,
196					       struct sk_buff *skb);
197extern struct pneigh_entry	*pneigh_lookup(struct neigh_table *tbl, const void *key, struct net_device *dev, int creat);
198extern int			pneigh_delete(struct neigh_table *tbl, const void *key, struct net_device *dev);
199
200struct netlink_callback;
201struct nlmsghdr;
202extern int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb);
203extern int neigh_add(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg);
204extern int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg);
205extern void neigh_app_ns(struct neighbour *n);
206
207extern int			neigh_sysctl_register(struct net_device *dev, struct neigh_parms *p,
208						      int p_id, int pdev_id, char *p_name);
209extern void			neigh_sysctl_unregister(struct neigh_parms *p);
210
211/*
212 *	Neighbour references
213 */
214
215static inline void neigh_release(struct neighbour *neigh)
216{
217	if (atomic_dec_and_test(&neigh->refcnt))
218		neigh_destroy(neigh);
219}
220
221static inline struct neighbour * neigh_clone(struct neighbour *neigh)
222{
223	if (neigh)
224		atomic_inc(&neigh->refcnt);
225	return neigh;
226}
227
228#define neigh_hold(n)	atomic_inc(&(n)->refcnt)
229
230static inline void neigh_confirm(struct neighbour *neigh)
231{
232	if (neigh)
233		neigh->confirmed = jiffies;
234}
235
236static inline int neigh_is_connected(struct neighbour *neigh)
237{
238	return neigh->nud_state&NUD_CONNECTED;
239}
240
241static inline int neigh_is_valid(struct neighbour *neigh)
242{
243	return neigh->nud_state&NUD_VALID;
244}
245
246static inline int neigh_event_send(struct neighbour *neigh, struct sk_buff *skb)
247{
248	neigh->used = jiffies;
249	if (!(neigh->nud_state&(NUD_CONNECTED|NUD_DELAY|NUD_PROBE)))
250		return __neigh_event_send(neigh, skb);
251	return 0;
252}
253
254static inline struct neighbour *
255__neigh_lookup(struct neigh_table *tbl, const void *pkey, struct net_device *dev, int creat)
256{
257	struct neighbour *n = neigh_lookup(tbl, pkey, dev);
258
259	if (n || !creat)
260		return n;
261
262	n = neigh_create(tbl, pkey, dev);
263	return IS_ERR(n) ? NULL : n;
264}
265
266static inline struct neighbour *
267__neigh_lookup_errno(struct neigh_table *tbl, const void *pkey,
268  struct net_device *dev)
269{
270	struct neighbour *n = neigh_lookup(tbl, pkey, dev);
271
272	if (n)
273		return n;
274
275	return neigh_create(tbl, pkey, dev);
276}
277
278#endif
279#endif
280
281
282