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 11 extern struct neigh_table arp_tbl; 12 13 static 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 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 29 static 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 42 static 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 58 void arp_init(void); 59 int arp_ioctl(struct net *net, unsigned int cmd, void __user *arg); 60 void 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); 64 int arp_mc_map(__be32 addr, u8 *haddr, struct net_device *dev, int dir); 65 void arp_ifdown(struct net_device *dev); 66 67 struct 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); 72 void arp_xmit(struct sk_buff *skb); 73 74 #endif /* _ARP_H */ 75