LXR linux/include/net/arp.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2/* linux/net/inet/arp.h */
   3#ifndef _ARP_H
   4#define _ARP_H
   5
   6#include <linux/if_arp.h>
   7#include <linux/hash.h>
   8#include <net/neighbour.h>
   9
  10
  11extern struct neigh_table arp_tbl;
  12
  13static inline u32 arp_hashfn(const void *pkey, const struct net_device *dev, u32 *hash_rnd)
  14{
  15        u32 key = *(const u32 *)pkey;
  16        u32 val = key ^ hash32_ptr(dev);
  17
  18        return val * hash_rnd[0];
  19}
  20
  21static 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
  29static inline struct neighbour *__ipv4_neigh_lookup(struct net_device *dev, u32 key)
  30{
  31        struct neighbour *n;
  32
  33        rcu_read_lock_bh();
  34        n = __ipv4_neigh_lookup_noref(dev, key);
  35        if (n && !refcount_inc_not_zero(&n->refcnt))
  36                n = NULL;
  37        rcu_read_unlock_bh();
  38
  39        return n;
  40}
  41
  42static inline void __ipv4_confirm_neigh(struct net_device *dev, u32 key)
  43{
  44        struct neighbour *n;
  45
  46        rcu_read_lock_bh();
  47        n = __ipv4_neigh_lookup_noref(dev, key);
  48        if (n) {
  49                unsigned long now = jiffies;
  50
  51                /* avoid dirtying neighbour */
  52                if (n->confirmed != now)
  53                        n->confirmed = now;
  54        }
  55        rcu_read_unlock_bh();
  56}
  57
  58void arp_init(void);
  59int arp_ioctl(struct net *net, unsigned int cmd, void __user *arg);
  60void arp_send(int type, int ptype, __be32 dest_ip,
  61              struct net_device *dev, __be32 src_ip,
  62              const unsigned char *dest_hw,
  63              const unsigned char *src_hw, const unsigned char *th);
  64int arp_mc_map(__be32 addr, u8 *haddr, struct net_device *dev, int dir);
  65void arp_ifdown(struct net_device *dev);
  66
  67struct sk_buff *arp_create(int type, int ptype, __be32 dest_ip,
  68                           struct net_device *dev, __be32 src_ip,
  69                           const unsigned char *dest_hw,
  70                           const unsigned char *src_hw,
  71                           const unsigned char *target_hw);
  72void arp_xmit(struct sk_buff *skb);
  73
  74#endif  /* _ARP_H */
  75