1#ifndef _NETFILTER_INGRESS_H_
 2#define _NETFILTER_INGRESS_H_
 3
 4#include <linux/netfilter.h>
 5#include <linux/netdevice.h>
 6
 7#ifdef CONFIG_NETFILTER_INGRESS
 8static inline bool nf_hook_ingress_active(const struct sk_buff *skb)
 9{
10#ifdef HAVE_JUMP_LABEL
11	if (!static_key_false(&nf_hooks_needed[NFPROTO_NETDEV][NF_NETDEV_INGRESS]))
12		return false;
13#endif
14	return rcu_access_pointer(skb->dev->nf_hooks_ingress);
15}
16
17/* caller must hold rcu_read_lock */
18static inline int nf_hook_ingress(struct sk_buff *skb)
19{
20	struct nf_hook_entry *e = rcu_dereference(skb->dev->nf_hooks_ingress);
21	struct nf_hook_state state;
22	int ret;
23
24	/* Must recheck the ingress hook head, in the event it became NULL
25	 * after the check in nf_hook_ingress_active evaluated to true.
26	 */
27	if (unlikely(!e))
28		return 0;
29
30	nf_hook_state_init(&state, NF_NETDEV_INGRESS,
31			   NFPROTO_NETDEV, skb->dev, NULL, NULL,
32			   dev_net(skb->dev), NULL);
33	ret = nf_hook_slow(skb, &state, e);
34	if (ret == 0)
35		return -1;
36
37	return ret;
38}
39
40static inline void nf_hook_ingress_init(struct net_device *dev)
41{
42	RCU_INIT_POINTER(dev->nf_hooks_ingress, NULL);
43}
44#else /* CONFIG_NETFILTER_INGRESS */
45static inline int nf_hook_ingress_active(struct sk_buff *skb)
46{
47	return 0;
48}
49
50static inline int nf_hook_ingress(struct sk_buff *skb)
51{
52	return 0;
53}
54
55static inline void nf_hook_ingress_init(struct net_device *dev) {}
56#endif /* CONFIG_NETFILTER_INGRESS */
57#endif /* _NETFILTER_INGRESS_H_ */