xref: /openbmc/linux/include/net/lwtunnel.h (revision 30357d7d)
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 #define LWTUNNEL_STATE_XMIT_REDIRECT	BIT(2)
17 
18 enum {
19 	LWTUNNEL_XMIT_DONE,
20 	LWTUNNEL_XMIT_CONTINUE,
21 };
22 
23 
24 struct lwtunnel_state {
25 	__u16		type;
26 	__u16		flags;
27 	__u16		headroom;
28 	atomic_t	refcnt;
29 	int		(*orig_output)(struct net *net, struct sock *sk, struct sk_buff *skb);
30 	int		(*orig_input)(struct sk_buff *);
31 	struct		rcu_head rcu;
32 	__u8            data[0];
33 };
34 
35 struct lwtunnel_encap_ops {
36 	int (*build_state)(struct nlattr *encap,
37 			   unsigned int family, const void *cfg,
38 			   struct lwtunnel_state **ts);
39 	void (*destroy_state)(struct lwtunnel_state *lws);
40 	int (*output)(struct net *net, struct sock *sk, struct sk_buff *skb);
41 	int (*input)(struct sk_buff *skb);
42 	int (*fill_encap)(struct sk_buff *skb,
43 			  struct lwtunnel_state *lwtstate);
44 	int (*get_encap_size)(struct lwtunnel_state *lwtstate);
45 	int (*cmp_encap)(struct lwtunnel_state *a, struct lwtunnel_state *b);
46 	int (*xmit)(struct sk_buff *skb);
47 
48 	struct module *owner;
49 };
50 
51 #ifdef CONFIG_LWTUNNEL
52 void lwtstate_free(struct lwtunnel_state *lws);
53 
54 static inline struct lwtunnel_state *
55 lwtstate_get(struct lwtunnel_state *lws)
56 {
57 	if (lws)
58 		atomic_inc(&lws->refcnt);
59 
60 	return lws;
61 }
62 
63 static inline void lwtstate_put(struct lwtunnel_state *lws)
64 {
65 	if (!lws)
66 		return;
67 
68 	if (atomic_dec_and_test(&lws->refcnt))
69 		lwtstate_free(lws);
70 }
71 
72 static inline bool lwtunnel_output_redirect(struct lwtunnel_state *lwtstate)
73 {
74 	if (lwtstate && (lwtstate->flags & LWTUNNEL_STATE_OUTPUT_REDIRECT))
75 		return true;
76 
77 	return false;
78 }
79 
80 static inline bool lwtunnel_input_redirect(struct lwtunnel_state *lwtstate)
81 {
82 	if (lwtstate && (lwtstate->flags & LWTUNNEL_STATE_INPUT_REDIRECT))
83 		return true;
84 
85 	return false;
86 }
87 
88 static inline bool lwtunnel_xmit_redirect(struct lwtunnel_state *lwtstate)
89 {
90 	if (lwtstate && (lwtstate->flags & LWTUNNEL_STATE_XMIT_REDIRECT))
91 		return true;
92 
93 	return false;
94 }
95 
96 static inline unsigned int lwtunnel_headroom(struct lwtunnel_state *lwtstate,
97 					     unsigned int mtu)
98 {
99 	if ((lwtunnel_xmit_redirect(lwtstate) ||
100 	     lwtunnel_output_redirect(lwtstate)) && lwtstate->headroom < mtu)
101 		return lwtstate->headroom;
102 
103 	return 0;
104 }
105 
106 int lwtunnel_encap_add_ops(const struct lwtunnel_encap_ops *op,
107 			   unsigned int num);
108 int lwtunnel_encap_del_ops(const struct lwtunnel_encap_ops *op,
109 			   unsigned int num);
110 int lwtunnel_valid_encap_type(u16 encap_type);
111 int lwtunnel_valid_encap_type_attr(struct nlattr *attr, int len);
112 int lwtunnel_build_state(u16 encap_type,
113 			 struct nlattr *encap,
114 			 unsigned int family, const void *cfg,
115 			 struct lwtunnel_state **lws);
116 int lwtunnel_fill_encap(struct sk_buff *skb,
117 			struct lwtunnel_state *lwtstate);
118 int lwtunnel_get_encap_size(struct lwtunnel_state *lwtstate);
119 struct lwtunnel_state *lwtunnel_state_alloc(int hdr_len);
120 int lwtunnel_cmp_encap(struct lwtunnel_state *a, struct lwtunnel_state *b);
121 int lwtunnel_output(struct net *net, struct sock *sk, struct sk_buff *skb);
122 int lwtunnel_input(struct sk_buff *skb);
123 int lwtunnel_xmit(struct sk_buff *skb);
124 
125 #else
126 
127 static inline void lwtstate_free(struct lwtunnel_state *lws)
128 {
129 }
130 
131 static inline struct lwtunnel_state *
132 lwtstate_get(struct lwtunnel_state *lws)
133 {
134 	return lws;
135 }
136 
137 static inline void lwtstate_put(struct lwtunnel_state *lws)
138 {
139 }
140 
141 static inline bool lwtunnel_output_redirect(struct lwtunnel_state *lwtstate)
142 {
143 	return false;
144 }
145 
146 static inline bool lwtunnel_input_redirect(struct lwtunnel_state *lwtstate)
147 {
148 	return false;
149 }
150 
151 static inline bool lwtunnel_xmit_redirect(struct lwtunnel_state *lwtstate)
152 {
153 	return false;
154 }
155 
156 static inline unsigned int lwtunnel_headroom(struct lwtunnel_state *lwtstate,
157 					     unsigned int mtu)
158 {
159 	return 0;
160 }
161 
162 static inline int lwtunnel_encap_add_ops(const struct lwtunnel_encap_ops *op,
163 					 unsigned int num)
164 {
165 	return -EOPNOTSUPP;
166 
167 }
168 
169 static inline int lwtunnel_encap_del_ops(const struct lwtunnel_encap_ops *op,
170 					 unsigned int num)
171 {
172 	return -EOPNOTSUPP;
173 }
174 
175 static inline int lwtunnel_valid_encap_type(u16 encap_type)
176 {
177 	return -EOPNOTSUPP;
178 }
179 static inline int lwtunnel_valid_encap_type_attr(struct nlattr *attr, int len)
180 {
181 	return -EOPNOTSUPP;
182 }
183 
184 static inline int lwtunnel_build_state(u16 encap_type,
185 				       struct nlattr *encap,
186 				       unsigned int family, const void *cfg,
187 				       struct lwtunnel_state **lws)
188 {
189 	return -EOPNOTSUPP;
190 }
191 
192 static inline int lwtunnel_fill_encap(struct sk_buff *skb,
193 				      struct lwtunnel_state *lwtstate)
194 {
195 	return 0;
196 }
197 
198 static inline int lwtunnel_get_encap_size(struct lwtunnel_state *lwtstate)
199 {
200 	return 0;
201 }
202 
203 static inline struct lwtunnel_state *lwtunnel_state_alloc(int hdr_len)
204 {
205 	return NULL;
206 }
207 
208 static inline int lwtunnel_cmp_encap(struct lwtunnel_state *a,
209 				     struct lwtunnel_state *b)
210 {
211 	return 0;
212 }
213 
214 static inline int lwtunnel_output(struct net *net, struct sock *sk, struct sk_buff *skb)
215 {
216 	return -EOPNOTSUPP;
217 }
218 
219 static inline int lwtunnel_input(struct sk_buff *skb)
220 {
221 	return -EOPNOTSUPP;
222 }
223 
224 static inline int lwtunnel_xmit(struct sk_buff *skb)
225 {
226 	return -EOPNOTSUPP;
227 }
228 
229 #endif /* CONFIG_LWTUNNEL */
230 
231 #define MODULE_ALIAS_RTNL_LWT(encap_type) MODULE_ALIAS("rtnl-lwt-" __stringify(encap_type))
232 
233 #endif /* __NET_LWTUNNEL_H */
234