summaryrefslogtreecommitdiffstats
path: root/include/net/lwtunnel.h
blob: ea3f80f58fd6d57f01d4cd9d7cbe659e7a123150 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
#ifndef __NET_LWTUNNEL_H
#define __NET_LWTUNNEL_H 1

#include <linux/lwtunnel.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/types.h>
#include <net/route.h>

#define LWTUNNEL_HASH_BITS   7
#define LWTUNNEL_HASH_SIZE   (1 << LWTUNNEL_HASH_BITS)

/* lw tunnel state flags */
#define LWTUNNEL_STATE_OUTPUT_REDIRECT	BIT(0)
#define LWTUNNEL_STATE_INPUT_REDIRECT	BIT(1)
#define LWTUNNEL_STATE_XMIT_REDIRECT	BIT(2)

enum {
	LWTUNNEL_XMIT_DONE,
	LWTUNNEL_XMIT_CONTINUE,
};


struct lwtunnel_state {
	__u16		type;
	__u16		flags;
	atomic_t	refcnt;
	int		(*orig_output)(struct net *net, struct sock *sk, struct sk_buff *skb);
	int		(*orig_input)(struct sk_buff *);
	int             len;
	__u16		headroom;
	__u8            data[0];
};

struct lwtunnel_encap_ops {
	int (*build_state)(struct net_device *dev, struct nlattr *encap,
			   unsigned int family, const void *cfg,
			   struct lwtunnel_state **ts);
	int (*output)(struct net *net, struct sock *sk, struct sk_buff *skb);
	int (*input)(struct sk_buff *skb);
	int (*fill_encap)(struct sk_buff *skb,
			  struct lwtunnel_state *lwtstate);
	int (*get_encap_size)(struct lwtunnel_state *lwtstate);
	int (*cmp_encap)(struct lwtunnel_state *a, struct lwtunnel_state *b);
	int (*xmit)(struct sk_buff *skb);
};

#ifdef CONFIG_LWTUNNEL
static inline void lwtstate_free(struct lwtunnel_state *lws)
{
	kfree(lws);
}

static inline struct lwtunnel_state *
lwtstate_get(struct lwtunnel_state *lws)
{
	if (lws)
		atomic_inc(&lws->refcnt);

	return lws;
}

static inline void lwtstate_put(struct lwtunnel_state *lws)
{
	if (!lws)
		return;

	if (atomic_dec_and_test(&lws->refcnt))
		lwtstate_free(lws);
}

static inline bool lwtunnel_output_redirect(struct lwtunnel_state *lwtstate)
{
	if (lwtstate && (lwtstate->flags & LWTUNNEL_STATE_OUTPUT_REDIRECT))
		return true;

	return false;
}

static inline bool lwtunnel_input_redirect(struct lwtunnel_state *lwtstate)
{
	if (lwtstate && (lwtstate->flags & LWTUNNEL_STATE_INPUT_REDIRECT))
		return true;

	return false;
}

static inline bool lwtunnel_xmit_redirect(struct lwtunnel_state *lwtstate)
{
	if (lwtstate && (lwtstate->flags & LWTUNNEL_STATE_XMIT_REDIRECT))
		return true;

	return false;
}

static inline unsigned int lwtunnel_headroom(struct lwtunnel_state *lwtstate,
					     unsigned int mtu)
{
	if (lwtunnel_xmit_redirect(lwtstate) && lwtstate->headroom < mtu)
		return lwtstate->headroom;

	return 0;
}

int lwtunnel_encap_add_ops(const struct lwtunnel_encap_ops *op,
			   unsigned int num);
int lwtunnel_encap_del_ops(const struct lwtunnel_encap_ops *op,
			   unsigned int num);
int lwtunnel_build_state(struct net_device *dev, u16 encap_type,
			 struct nlattr *encap,
			 unsigned int family, const void *cfg,
			 struct lwtunnel_state **lws);
int lwtunnel_fill_encap(struct sk_buff *skb,
			struct lwtunnel_state *lwtstate);
int lwtunnel_get_encap_size(struct lwtunnel_state *lwtstate);
struct lwtunnel_state *lwtunnel_state_alloc(int hdr_len);
int lwtunnel_cmp_encap(struct lwtunnel_state *a, struct lwtunnel_state *b);
int lwtunnel_output(struct net *net, struct sock *sk, struct sk_buff *skb);
int lwtunnel_input(struct sk_buff *skb);
int lwtunnel_xmit(struct sk_buff *skb);

#else

static inline void lwtstate_free(struct lwtunnel_state *lws)
{
}

static inline struct lwtunnel_state *
lwtstate_get(struct lwtunnel_state *lws)
{
	return lws;
}

static inline void lwtstate_put(struct lwtunnel_state *lws)
{
}

static inline bool lwtunnel_output_redirect(struct lwtunnel_state *lwtstate)
{
	return false;
}

static inline bool lwtunnel_input_redirect(struct lwtunnel_state *lwtstate)
{
	return false;
}

static inline bool lwtunnel_xmit_redirect(struct lwtunnel_state *lwtstate)
{
	return false;
}

static inline unsigned int lwtunnel_headroom(struct lwtunnel_state *lwtstate,
					     unsigned int mtu)
{
	return 0;
}

static inline int lwtunnel_encap_add_ops(const struct lwtunnel_encap_ops *op,
					 unsigned int num)
{
	return -EOPNOTSUPP;

}

static inline int lwtunnel_encap_del_ops(const struct lwtunnel_encap_ops *op,
					 unsigned int num)
{
	return -EOPNOTSUPP;
}

static inline int lwtunnel_build_state(struct net_device *dev, u16 encap_type,
				       struct nlattr *encap,
				       unsigned int family, const void *cfg,
				       struct lwtunnel_state **lws)
{
	return -EOPNOTSUPP;
}

static inline int lwtunnel_fill_encap(struct sk_buff *skb,
				      struct lwtunnel_state *lwtstate)
{
	return 0;
}

static inline int lwtunnel_get_encap_size(struct lwtunnel_state *lwtstate)
{
	return 0;
}

static inline struct lwtunnel_state *lwtunnel_state_alloc(int hdr_len)
{
	return NULL;
}

static inline int lwtunnel_cmp_encap(struct lwtunnel_state *a,
				     struct lwtunnel_state *b)
{
	return 0;
}

static inline int lwtunnel_output(struct net *net, struct sock *sk, struct sk_buff *skb)
{
	return -EOPNOTSUPP;
}

static inline int lwtunnel_input(struct sk_buff *skb)
{
	return -EOPNOTSUPP;
}

static inline int lwtunnel_xmit(struct sk_buff *skb)
{
	return -EOPNOTSUPP;
}

#endif /* CONFIG_LWTUNNEL */

#define MODULE_ALIAS_RTNL_LWT(encap_type) MODULE_ALIAS("rtnl-lwt-" __stringify(encap_type))

#endif /* __NET_LWTUNNEL_H */