1 /* linux/net/inet/arp.h */
2 #ifndef _ARP_H
3 #define _ARP_H
4
5 #include <linux/if_arp.h>
6 #include <linux/hash.h>
7 #include <net/neighbour.h>
8
9
10 extern struct neigh_table arp_tbl;
11
arp_hashfn(u32 key,const struct net_device * dev,u32 hash_rnd)12 static inline u32 arp_hashfn(u32 key, const struct net_device *dev, u32 hash_rnd)
13 {
14 u32 val = key ^ hash32_ptr(dev);
15
16 return val * hash_rnd;
17 }
18
__ipv4_neigh_lookup_noref(struct net_device * dev,u32 key)19 static inline struct neighbour *__ipv4_neigh_lookup_noref(struct net_device *dev, u32 key)
20 {
21 struct neigh_hash_table *nht = rcu_dereference_bh(arp_tbl.nht);
22 struct neighbour *n;
23 u32 hash_val;
24
25 hash_val = arp_hashfn(key, dev, nht->hash_rnd[0]) >> (32 - nht->hash_shift);
26 for (n = rcu_dereference_bh(nht->hash_buckets[hash_val]);
27 n != NULL;
28 n = rcu_dereference_bh(n->next)) {
29 if (n->dev == dev && *(u32 *)n->primary_key == key)
30 return n;
31 }
32
33 return NULL;
34 }
35
__ipv4_neigh_lookup(struct net_device * dev,u32 key)36 static inline struct neighbour *__ipv4_neigh_lookup(struct net_device *dev, u32 key)
37 {
38 struct neighbour *n;
39
40 rcu_read_lock_bh();
41 n = __ipv4_neigh_lookup_noref(dev, key);
42 if (n && !atomic_inc_not_zero(&n->refcnt))
43 n = NULL;
44 rcu_read_unlock_bh();
45
46 return n;
47 }
48
49 extern void arp_init(void);
50 extern int arp_find(unsigned char *haddr, struct sk_buff *skb);
51 extern int arp_ioctl(struct net *net, unsigned int cmd, void __user *arg);
52 extern void arp_send(int type, int ptype, __be32 dest_ip,
53 struct net_device *dev, __be32 src_ip,
54 const unsigned char *dest_hw,
55 const unsigned char *src_hw, const unsigned char *th);
56 extern int arp_mc_map(__be32 addr, u8 *haddr, struct net_device *dev, int dir);
57 extern void arp_ifdown(struct net_device *dev);
58
59 extern struct sk_buff *arp_create(int type, int ptype, __be32 dest_ip,
60 struct net_device *dev, __be32 src_ip,
61 const unsigned char *dest_hw,
62 const unsigned char *src_hw,
63 const unsigned char *target_hw);
64 extern void arp_xmit(struct sk_buff *skb);
65 int arp_invalidate(struct net_device *dev, __be32 ip);
66
67 #endif /* _ARP_H */
68