include/net/arp.h

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