xref: /linux/include/net/arp.h (revision 827634added7f38b7d724cab1dccdb2b004c13c3)
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 
12 static inline u32 arp_hashfn(const void *pkey, const struct net_device *dev, u32 *hash_rnd)
13 {
14 	u32 key = *(const u32 *)pkey;
15 	u32 val = key ^ hash32_ptr(dev);
16 
17 	return val * hash_rnd[0];
18 }
19 
20 static inline struct neighbour *__ipv4_neigh_lookup_noref(struct net_device *dev, u32 key)
21 {
22 	return ___neigh_lookup_noref(&arp_tbl, neigh_key_eq32, arp_hashfn, &key, dev);
23 }
24 
25 static inline struct neighbour *__ipv4_neigh_lookup(struct net_device *dev, u32 key)
26 {
27 	struct neighbour *n;
28 
29 	rcu_read_lock_bh();
30 	n = __ipv4_neigh_lookup_noref(dev, key);
31 	if (n && !atomic_inc_not_zero(&n->refcnt))
32 		n = NULL;
33 	rcu_read_unlock_bh();
34 
35 	return n;
36 }
37 
38 void arp_init(void);
39 int arp_ioctl(struct net *net, unsigned int cmd, void __user *arg);
40 void arp_send(int type, int ptype, __be32 dest_ip,
41 	      struct net_device *dev, __be32 src_ip,
42 	      const unsigned char *dest_hw,
43 	      const unsigned char *src_hw, const unsigned char *th);
44 int arp_mc_map(__be32 addr, u8 *haddr, struct net_device *dev, int dir);
45 void arp_ifdown(struct net_device *dev);
46 
47 struct sk_buff *arp_create(int type, int ptype, __be32 dest_ip,
48 			   struct net_device *dev, __be32 src_ip,
49 			   const unsigned char *dest_hw,
50 			   const unsigned char *src_hw,
51 			   const unsigned char *target_hw);
52 void arp_xmit(struct sk_buff *skb);
53 
54 #endif	/* _ARP_H */
55