summaryrefslogtreecommitdiffstats
path: root/net/core/lwtunnel.c
blob: d7ae3a235b4b08edb4ce3dcdaf64d80f24031f2d (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
/*
 * lwtunnel	Infrastructure for light weight tunnels like mpls
 *
 * Authors:	Roopa Prabhu, <roopa@cumulusnetworks.com>
 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 *
 */

#include <linux/capability.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/lwtunnel.h>
#include <linux/in.h>
#include <linux/init.h>
#include <linux/err.h>

#include <net/lwtunnel.h>
#include <net/rtnetlink.h>

struct lwtunnel_state *lwtunnel_state_alloc(int encap_len)
{
	struct lwtunnel_state *lws;

	lws = kzalloc(sizeof(*lws) + encap_len, GFP_ATOMIC);

	return lws;
}
EXPORT_SYMBOL(lwtunnel_state_alloc);

const struct lwtunnel_encap_ops __rcu *
		lwtun_encaps[LWTUNNEL_ENCAP_MAX + 1] __read_mostly;

int lwtunnel_encap_add_ops(const struct lwtunnel_encap_ops *ops,
			   unsigned int num)
{
	if (num > LWTUNNEL_ENCAP_MAX)
		return -ERANGE;

	return !cmpxchg((const struct lwtunnel_encap_ops **)
			&lwtun_encaps[num],
			NULL, ops) ? 0 : -1;
}
EXPORT_SYMBOL(lwtunnel_encap_add_ops);

int lwtunnel_encap_del_ops(const struct lwtunnel_encap_ops *ops,
			   unsigned int encap_type)
{
	int ret;

	if (encap_type == LWTUNNEL_ENCAP_NONE ||
	    encap_type > LWTUNNEL_ENCAP_MAX)
		return -ERANGE;

	ret = (cmpxchg((const struct lwtunnel_encap_ops **)
		       &lwtun_encaps[encap_type],
		       ops, NULL) == ops) ? 0 : -1;

	synchronize_net();

	return ret;
}
EXPORT_SYMBOL(lwtunnel_encap_del_ops);

int lwtunnel_build_state(struct net_device *dev, u16 encap_type,
			 struct nlattr *encap, struct lwtunnel_state **lws)
{
	const struct lwtunnel_encap_ops *ops;
	int ret = -EINVAL;

	if (encap_type == LWTUNNEL_ENCAP_NONE ||
	    encap_type > LWTUNNEL_ENCAP_MAX)
		return ret;

	ret = -EOPNOTSUPP;
	rcu_read_lock();
	ops = rcu_dereference(lwtun_encaps[encap_type]);
	if (likely(ops && ops->build_state))
		ret = ops->build_state(dev, encap, lws);
	rcu_read_unlock();

	return ret;
}
EXPORT_SYMBOL(lwtunnel_build_state);

int lwtunnel_fill_encap(struct sk_buff *skb, struct lwtunnel_state *lwtstate)
{
	const struct lwtunnel_encap_ops *ops;
	struct nlattr *nest;
	int ret = -EINVAL;

	if (!lwtstate)
		return 0;

	if (lwtstate->type == LWTUNNEL_ENCAP_NONE ||
	    lwtstate->type > LWTUNNEL_ENCAP_MAX)
		return 0;

	ret = -EOPNOTSUPP;
	nest = nla_nest_start(skb, RTA_ENCAP);
	rcu_read_lock();
	ops = rcu_dereference(lwtun_encaps[lwtstate->type]);
	if (likely(ops && ops->fill_encap))
		ret = ops->fill_encap(skb, lwtstate);
	rcu_read_unlock();

	if (ret)
		goto nla_put_failure;
	nla_nest_end(skb, nest);
	ret = nla_put_u16(skb, RTA_ENCAP_TYPE, lwtstate->type);
	if (ret)
		goto nla_put_failure;

	return 0;

nla_put_failure:
	nla_nest_cancel(skb, nest);

	return (ret == -EOPNOTSUPP ? 0 : ret);
}
EXPORT_SYMBOL(lwtunnel_fill_encap);

int lwtunnel_get_encap_size(struct lwtunnel_state *lwtstate)
{
	const struct lwtunnel_encap_ops *ops;
	int ret = 0;

	if (!lwtstate)
		return 0;

	if (lwtstate->type == LWTUNNEL_ENCAP_NONE ||
	    lwtstate->type > LWTUNNEL_ENCAP_MAX)
		return 0;

	rcu_read_lock();
	ops = rcu_dereference(lwtun_encaps[lwtstate->type]);
	if (likely(ops && ops->get_encap_size))
		ret = nla_total_size(ops->get_encap_size(lwtstate));
	rcu_read_unlock();

	return ret;
}
EXPORT_SYMBOL(lwtunnel_get_encap_size);

int lwtunnel_cmp_encap(struct lwtunnel_state *a, struct lwtunnel_state *b)
{
	const struct lwtunnel_encap_ops *ops;
	int ret = 0;

	if (!a && !b)
		return 0;

	if (!a || !b)
		return 1;

	if (a->type != b->type)
		return 1;

	if (a->type == LWTUNNEL_ENCAP_NONE ||
	    a->type > LWTUNNEL_ENCAP_MAX)
		return 0;

	rcu_read_lock();
	ops = rcu_dereference(lwtun_encaps[a->type]);
	if (likely(ops && ops->cmp_encap))
		ret = ops->cmp_encap(a, b);
	rcu_read_unlock();

	return ret;
}
EXPORT_SYMBOL(lwtunnel_cmp_encap);
OpenPOWER on IntegriCloud