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(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 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 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