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(ptr: dev);
17
18 return val * hash_rnd[0];
19}
20
21#ifdef CONFIG_INET
22static inline struct neighbour *__ipv4_neigh_lookup_noref(struct net_device *dev, u32 key)
23{
24 if (dev->flags & (IFF_LOOPBACK | IFF_POINTOPOINT))
25 key = INADDR_ANY;
26
27 return ___neigh_lookup_noref(tbl: &arp_tbl, key_eq: neigh_key_eq32, hash: arp_hashfn, pkey: &key, dev);
28}
29#else
30static inline
31struct neighbour *__ipv4_neigh_lookup_noref(struct net_device *dev, u32 key)
32{
33 return NULL;
34}
35#endif
36
37static inline struct neighbour *__ipv4_neigh_lookup(struct net_device *dev, u32 key)
38{
39 struct neighbour *n;
40
41 rcu_read_lock();
42 n = __ipv4_neigh_lookup_noref(dev, key);
43 if (n && !refcount_inc_not_zero(r: &n->refcnt))
44 n = NULL;
45 rcu_read_unlock();
46
47 return n;
48}
49
50static inline void __ipv4_confirm_neigh(struct net_device *dev, u32 key)
51{
52 struct neighbour *n;
53
54 rcu_read_lock();
55 n = __ipv4_neigh_lookup_noref(dev, key);
56 neigh_confirm(n);
57 rcu_read_unlock();
58}
59
60void arp_init(void);
61int arp_ioctl(struct net *net, unsigned int cmd, void __user *arg);
62void arp_send(int type, int ptype, __be32 dest_ip,
63 struct net_device *dev, __be32 src_ip,
64 const unsigned char *dest_hw,
65 const unsigned char *src_hw, const unsigned char *th);
66int arp_mc_map(__be32 addr, u8 *haddr, struct net_device *dev, int dir);
67void arp_ifdown(struct net_device *dev);
68int arp_invalidate(struct net_device *dev, __be32 ip, bool force);
69
70struct sk_buff *arp_create(int type, int ptype, __be32 dest_ip,
71 struct net_device *dev, __be32 src_ip,
72 const unsigned char *dest_hw,
73 const unsigned char *src_hw,
74 const unsigned char *target_hw);
75void arp_xmit(struct sk_buff *skb);
76
77#endif /* _ARP_H */
78