xref: /linux/include/net/lwtunnel.h (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
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 
17 struct lwtunnel_state {
18 	__u16		type;
19 	__u16		flags;
20 	atomic_t	refcnt;
21 	int		(*orig_output)(struct sock *sk, struct sk_buff *skb);
22 	int		(*orig_input)(struct sk_buff *);
23 	int             len;
24 	__u8            data[0];
25 };
26 
27 struct 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 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
40 static inline void lwtstate_free(struct lwtunnel_state *lws)
41 {
42 	kfree(lws);
43 }
44 
45 static inline struct lwtunnel_state *
46 lwtstate_get(struct lwtunnel_state *lws)
47 {
48 	if (lws)
49 		atomic_inc(&lws->refcnt);
50 
51 	return lws;
52 }
53 
54 static 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 
63 static 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 
71 static 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 }
78 int lwtunnel_encap_add_ops(const struct lwtunnel_encap_ops *op,
79 			   unsigned int num);
80 int lwtunnel_encap_del_ops(const struct lwtunnel_encap_ops *op,
81 			   unsigned int num);
82 int 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);
86 int lwtunnel_fill_encap(struct sk_buff *skb,
87 			struct lwtunnel_state *lwtstate);
88 int lwtunnel_get_encap_size(struct lwtunnel_state *lwtstate);
89 struct lwtunnel_state *lwtunnel_state_alloc(int hdr_len);
90 int lwtunnel_cmp_encap(struct lwtunnel_state *a, struct lwtunnel_state *b);
91 int lwtunnel_output(struct sock *sk, struct sk_buff *skb);
92 int lwtunnel_input(struct sk_buff *skb);
93 
94 #else
95 
96 static inline void lwtstate_free(struct lwtunnel_state *lws)
97 {
98 }
99 
100 static inline struct lwtunnel_state *
101 lwtstate_get(struct lwtunnel_state *lws)
102 {
103 	return lws;
104 }
105 
106 static inline void lwtstate_put(struct lwtunnel_state *lws)
107 {
108 }
109 
110 static inline bool lwtunnel_output_redirect(struct lwtunnel_state *lwtstate)
111 {
112 	return false;
113 }
114 
115 static inline bool lwtunnel_input_redirect(struct lwtunnel_state *lwtstate)
116 {
117 	return false;
118 }
119 
120 static inline int lwtunnel_encap_add_ops(const struct lwtunnel_encap_ops *op,
121 					 unsigned int num)
122 {
123 	return -EOPNOTSUPP;
124 
125 }
126 
127 static inline int lwtunnel_encap_del_ops(const struct lwtunnel_encap_ops *op,
128 					 unsigned int num)
129 {
130 	return -EOPNOTSUPP;
131 }
132 
133 static 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 
141 static inline int lwtunnel_fill_encap(struct sk_buff *skb,
142 				      struct lwtunnel_state *lwtstate)
143 {
144 	return 0;
145 }
146 
147 static inline int lwtunnel_get_encap_size(struct lwtunnel_state *lwtstate)
148 {
149 	return 0;
150 }
151 
152 static inline struct lwtunnel_state *lwtunnel_state_alloc(int hdr_len)
153 {
154 	return NULL;
155 }
156 
157 static inline int lwtunnel_cmp_encap(struct lwtunnel_state *a,
158 				     struct lwtunnel_state *b)
159 {
160 	return 0;
161 }
162 
163 static inline int lwtunnel_output(struct sock *sk, struct sk_buff *skb)
164 {
165 	return -EOPNOTSUPP;
166 }
167 
168 static inline int lwtunnel_input(struct sk_buff *skb)
169 {
170 	return -EOPNOTSUPP;
171 }
172 
173 #endif
174 
175 #endif /* __NET_LWTUNNEL_H */
176