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 <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 #ifdef CONFIG_INET
  21 static inline struct neighbour *__ipv4_neigh_lookup_noref(struct net_device *dev, u32 key)
  22 {
  23         if (dev->flags & (IFF_LOOPBACK | IFF_POINTOPOINT))
  24                 key = INADDR_ANY;
  25
  26         return ___neigh_lookup_noref(&arp_tbl, neigh_key_eq32, arp_hashfn, &key, dev);
  27 }
  28 #else
  29 static inline
  30 struct neighbour *__ipv4_neigh_lookup_noref(struct net_device *dev, u32 key)
  31 {
  32         return NULL;
  33 }
  34 #endif
  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 void arp_init(void);
  50 int arp_ioctl(struct net *net, unsigned int cmd, void __user *arg);
  51 void arp_send(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, const unsigned char *th);
  55 int arp_mc_map(__be32 addr, u8 *haddr, struct net_device *dev, int dir);
  56 void arp_ifdown(struct net_device *dev);
  57
  58 struct sk_buff *arp_create(int type, int ptype, __be32 dest_ip,
  59                            struct net_device *dev, __be32 src_ip,
  60                            const unsigned char *dest_hw,
  61                            const unsigned char *src_hw,
  62                            const unsigned char *target_hw);
  63 void arp_xmit(struct sk_buff *skb);
  64
  65 #endif  /* _ARP_H */