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
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
18enum {
19 LWTUNNEL_XMIT_DONE,
20 LWTUNNEL_XMIT_CONTINUE,
21};
22
23
24struct 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
35struct 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
52void lwtstate_free(struct lwtunnel_state *lws);
53
54static inline struct lwtunnel_state *
55lwtstate_get(struct lwtunnel_state *lws)
56{
57 if (lws)
58 atomic_inc(&lws->refcnt);
59
60 return lws;
61}
62
63static 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
72static 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
80static 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
88static 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
96static 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
106int lwtunnel_encap_add_ops(const struct lwtunnel_encap_ops *op,
107 unsigned int num);
108int lwtunnel_encap_del_ops(const struct lwtunnel_encap_ops *op,
109 unsigned int num);
110int lwtunnel_valid_encap_type(u16 encap_type);
111int lwtunnel_valid_encap_type_attr(struct nlattr *attr, int len);
112int lwtunnel_build_state(u16 encap_type,
113 struct nlattr *encap,
114 unsigned int family, const void *cfg,
115 struct lwtunnel_state **lws);
116int lwtunnel_fill_encap(struct sk_buff *skb,
117 struct lwtunnel_state *lwtstate);
118int lwtunnel_get_encap_size(struct lwtunnel_state *lwtstate);
119struct lwtunnel_state *lwtunnel_state_alloc(int hdr_len);
120int lwtunnel_cmp_encap(struct lwtunnel_state *a, struct lwtunnel_state *b);
121int lwtunnel_output(struct net *net, struct sock *sk, struct sk_buff *skb);
122int lwtunnel_input(struct sk_buff *skb);
123int lwtunnel_xmit(struct sk_buff *skb);
124
125#else
126
127static inline void lwtstate_free(struct lwtunnel_state *lws)
128{
129}
130
131static inline struct lwtunnel_state *
132lwtstate_get(struct lwtunnel_state *lws)
133{
134 return lws;
135}
136
137static inline void lwtstate_put(struct lwtunnel_state *lws)
138{
139}
140
141static inline bool lwtunnel_output_redirect(struct lwtunnel_state *lwtstate)
142{
143 return false;
144}
145
146static inline bool lwtunnel_input_redirect(struct lwtunnel_state *lwtstate)
147{
148 return false;
149}
150
151static inline bool lwtunnel_xmit_redirect(struct lwtunnel_state *lwtstate)
152{
153 return false;
154}
155
156static inline unsigned int lwtunnel_headroom(struct lwtunnel_state *lwtstate,
157 unsigned int mtu)
158{
159 return 0;
160}
161
162static inline int lwtunnel_encap_add_ops(const struct lwtunnel_encap_ops *op,
163 unsigned int num)
164{
165 return -EOPNOTSUPP;
166
167}
168
169static inline int lwtunnel_encap_del_ops(const struct lwtunnel_encap_ops *op,
170 unsigned int num)
171{
172 return -EOPNOTSUPP;
173}
174
175static inline int lwtunnel_valid_encap_type(u16 encap_type)
176{
177 return -EOPNOTSUPP;
178}
179static inline int lwtunnel_valid_encap_type_attr(struct nlattr *attr, int len)
180{
181
182
183
184 return 0;
185}
186
187static inline int lwtunnel_build_state(u16 encap_type,
188 struct nlattr *encap,
189 unsigned int family, const void *cfg,
190 struct lwtunnel_state **lws)
191{
192 return -EOPNOTSUPP;
193}
194
195static inline int lwtunnel_fill_encap(struct sk_buff *skb,
196 struct lwtunnel_state *lwtstate)
197{
198 return 0;
199}
200
201static inline int lwtunnel_get_encap_size(struct lwtunnel_state *lwtstate)
202{
203 return 0;
204}
205
206static inline struct lwtunnel_state *lwtunnel_state_alloc(int hdr_len)
207{
208 return NULL;
209}
210
211static inline int lwtunnel_cmp_encap(struct lwtunnel_state *a,
212 struct lwtunnel_state *b)
213{
214 return 0;
215}
216
217static inline int lwtunnel_output(struct net *net, struct sock *sk, struct sk_buff *skb)
218{
219 return -EOPNOTSUPP;
220}
221
222static inline int lwtunnel_input(struct sk_buff *skb)
223{
224 return -EOPNOTSUPP;
225}
226
227static inline int lwtunnel_xmit(struct sk_buff *skb)
228{
229 return -EOPNOTSUPP;
230}
231
232#endif
233
234#define MODULE_ALIAS_RTNL_LWT(encap_type) MODULE_ALIAS("rtnl-lwt-" __stringify(encap_type))
235
236#endif
237
