1#ifndef __NET_LWTUNNEL_H
  2#define __NET_LWTUNNEL_H 1
  3
  4#include <linux/lwtunnel.h>
  5#include <linux/netdevice.h>
  6#include <linux/skbuff.h>
  7#include <linux/types.h>
  8#include <net/route.h>
  9
 10#define LWTUNNEL_HASH_BITS   7
 11#define LWTUNNEL_HASH_SIZE   (1 << LWTUNNEL_HASH_BITS)
 12
 13/* lw tunnel state flags */
 14#define LWTUNNEL_STATE_OUTPUT_REDIRECT	BIT(0)
 15#define LWTUNNEL_STATE_INPUT_REDIRECT	BIT(1)
 16
 17struct lwtunnel_state {
 18	__u16		type;
 19	__u16		flags;
 20	atomic_t	refcnt;
 21	int		(*orig_output)(struct net *net, struct sock *sk, struct sk_buff *skb);
 22	int		(*orig_input)(struct sk_buff *);
 23	int             len;
 24	__u8            data[0];
 25};
 26
 27struct lwtunnel_encap_ops {
 28	int (*build_state)(struct net_device *dev, struct nlattr *encap,
 29			   unsigned int family, const void *cfg,
 30			   struct lwtunnel_state **ts);
 31	int (*output)(struct net *net, struct sock *sk, struct sk_buff *skb);
 32	int (*input)(struct sk_buff *skb);
 33	int (*fill_encap)(struct sk_buff *skb,
 34			  struct lwtunnel_state *lwtstate);
 35	int (*get_encap_size)(struct lwtunnel_state *lwtstate);
 36	int (*cmp_encap)(struct lwtunnel_state *a, struct lwtunnel_state *b);
 37};
 38
 39#ifdef CONFIG_LWTUNNEL
 40static inline void lwtstate_free(struct lwtunnel_state *lws)
 41{
 42	kfree(lws);
 43}
 44
 45static inline struct lwtunnel_state *
 46lwtstate_get(struct lwtunnel_state *lws)
 47{
 48	if (lws)
 49		atomic_inc(&lws->refcnt);
 50
 51	return lws;
 52}
 53
 54static inline void lwtstate_put(struct lwtunnel_state *lws)
 55{
 56	if (!lws)
 57		return;
 58
 59	if (atomic_dec_and_test(&lws->refcnt))
 60		lwtstate_free(lws);
 61}
 62
 63static inline bool lwtunnel_output_redirect(struct lwtunnel_state *lwtstate)
 64{
 65	if (lwtstate && (lwtstate->flags & LWTUNNEL_STATE_OUTPUT_REDIRECT))
 66		return true;
 67
 68	return false;
 69}
 70
 71static inline bool lwtunnel_input_redirect(struct lwtunnel_state *lwtstate)
 72{
 73	if (lwtstate && (lwtstate->flags & LWTUNNEL_STATE_INPUT_REDIRECT))
 74		return true;
 75
 76	return false;
 77}
 78int lwtunnel_encap_add_ops(const struct lwtunnel_encap_ops *op,
 79			   unsigned int num);
 80int lwtunnel_encap_del_ops(const struct lwtunnel_encap_ops *op,
 81			   unsigned int num);
 82int lwtunnel_build_state(struct net_device *dev, u16 encap_type,
 83			 struct nlattr *encap,
 84			 unsigned int family, const void *cfg,
 85			 struct lwtunnel_state **lws);
 86int lwtunnel_fill_encap(struct sk_buff *skb,
 87			struct lwtunnel_state *lwtstate);
 88int lwtunnel_get_encap_size(struct lwtunnel_state *lwtstate);
 89struct lwtunnel_state *lwtunnel_state_alloc(int hdr_len);
 90int lwtunnel_cmp_encap(struct lwtunnel_state *a, struct lwtunnel_state *b);
 91int lwtunnel_output(struct net *net, struct sock *sk, struct sk_buff *skb);
 92int lwtunnel_input(struct sk_buff *skb);
 93
 94#else
 95
 96static inline void lwtstate_free(struct lwtunnel_state *lws)
 97{
 98}
 99
100static inline struct lwtunnel_state *
101lwtstate_get(struct lwtunnel_state *lws)
102{
103	return lws;
104}
105
106static inline void lwtstate_put(struct lwtunnel_state *lws)
107{
108}
109
110static inline bool lwtunnel_output_redirect(struct lwtunnel_state *lwtstate)
111{
112	return false;
113}
114
115static inline bool lwtunnel_input_redirect(struct lwtunnel_state *lwtstate)
116{
117	return false;
118}
119
120static inline int lwtunnel_encap_add_ops(const struct lwtunnel_encap_ops *op,
121					 unsigned int num)
122{
123	return -EOPNOTSUPP;
124
125}
126
127static inline int lwtunnel_encap_del_ops(const struct lwtunnel_encap_ops *op,
128					 unsigned int num)
129{
130	return -EOPNOTSUPP;
131}
132
133static inline int lwtunnel_build_state(struct net_device *dev, u16 encap_type,
134				       struct nlattr *encap,
135				       unsigned int family, const void *cfg,
136				       struct lwtunnel_state **lws)
137{
138	return -EOPNOTSUPP;
139}
140
141static inline int lwtunnel_fill_encap(struct sk_buff *skb,
142				      struct lwtunnel_state *lwtstate)
143{
144	return 0;
145}
146
147static inline int lwtunnel_get_encap_size(struct lwtunnel_state *lwtstate)
148{
149	return 0;
150}
151
152static inline struct lwtunnel_state *lwtunnel_state_alloc(int hdr_len)
153{
154	return NULL;
155}
156
157static inline int lwtunnel_cmp_encap(struct lwtunnel_state *a,
158				     struct lwtunnel_state *b)
159{
160	return 0;
161}
162
163static inline int lwtunnel_output(struct net *net, struct sock *sk, struct sk_buff *skb)
164{
165	return -EOPNOTSUPP;
166}
167
168static inline int lwtunnel_input(struct sk_buff *skb)
169{
170	return -EOPNOTSUPP;
171}
172
173#endif /* CONFIG_LWTUNNEL */
174
175#define MODULE_ALIAS_RTNL_LWT(encap_type) MODULE_ALIAS("rtnl-lwt-" __stringify(encap_type))
176
177#endif /* __NET_LWTUNNEL_H */