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
|
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/netfilter.h>
#include <linux/mutex.h>
#include <net/sock.h>
#include "nf_internals.h"
/* Sockopts only registered and called from user context, so
net locking would be overkill. Also, [gs]etsockopt calls may
sleep. */
static DEFINE_MUTEX(nf_sockopt_mutex);
static LIST_HEAD(nf_sockopts);
/* Do exclusive ranges overlap? */
static inline int overlap(int min1, int max1, int min2, int max2)
{
return max1 > min2 && min1 < max2;
}
/* Functions to register sockopt ranges (exclusive). */
int nf_register_sockopt(struct nf_sockopt_ops *reg)
{
struct nf_sockopt_ops *ops;
int ret = 0;
if (mutex_lock_interruptible(&nf_sockopt_mutex) != 0)
return -EINTR;
list_for_each_entry(ops, &nf_sockopts, list) {
if (ops->pf == reg->pf
&& (overlap(ops->set_optmin, ops->set_optmax,
reg->set_optmin, reg->set_optmax)
|| overlap(ops->get_optmin, ops->get_optmax,
reg->get_optmin, reg->get_optmax))) {
NFDEBUG("nf_sock overlap: %u-%u/%u-%u v %u-%u/%u-%u\n",
ops->set_optmin, ops->set_optmax,
ops->get_optmin, ops->get_optmax,
reg->set_optmin, reg->set_optmax,
reg->get_optmin, reg->get_optmax);
ret = -EBUSY;
goto out;
}
}
list_add(®->list, &nf_sockopts);
out:
mutex_unlock(&nf_sockopt_mutex);
return ret;
}
EXPORT_SYMBOL(nf_register_sockopt);
void nf_unregister_sockopt(struct nf_sockopt_ops *reg)
{
mutex_lock(&nf_sockopt_mutex);
list_del(®->list);
mutex_unlock(&nf_sockopt_mutex);
}
EXPORT_SYMBOL(nf_unregister_sockopt);
static struct nf_sockopt_ops *nf_sockopt_find(struct sock *sk, int pf,
int val, int get)
{
struct nf_sockopt_ops *ops;
if (sock_net(sk) != &init_net)
return ERR_PTR(-ENOPROTOOPT);
if (mutex_lock_interruptible(&nf_sockopt_mutex) != 0)
return ERR_PTR(-EINTR);
list_for_each_entry(ops, &nf_sockopts, list) {
if (ops->pf == pf) {
if (!try_module_get(ops->owner))
goto out_nosup;
if (get) {
if (val >= ops->get_optmin &&
val < ops->get_optmax)
goto out;
} else {
if (val >= ops->set_optmin &&
val < ops->set_optmax)
goto out;
}
module_put(ops->owner);
}
}
out_nosup:
ops = ERR_PTR(-ENOPROTOOPT);
out:
mutex_unlock(&nf_sockopt_mutex);
return ops;
}
/* Call get/setsockopt() */
static int nf_sockopt(struct sock *sk, int pf, int val,
char __user *opt, int *len, int get)
{
struct nf_sockopt_ops *ops;
int ret;
ops = nf_sockopt_find(sk, pf, val, get);
if (IS_ERR(ops))
return PTR_ERR(ops);
if (get)
ret = ops->get(sk, val, opt, len);
else
ret = ops->set(sk, val, opt, *len);
module_put(ops->owner);
return ret;
}
int nf_setsockopt(struct sock *sk, int pf, int val, char __user *opt,
int len)
{
return nf_sockopt(sk, pf, val, opt, &len, 0);
}
EXPORT_SYMBOL(nf_setsockopt);
int nf_getsockopt(struct sock *sk, int pf, int val, char __user *opt, int *len)
{
return nf_sockopt(sk, pf, val, opt, len, 1);
}
EXPORT_SYMBOL(nf_getsockopt);
#ifdef CONFIG_COMPAT
static int compat_nf_sockopt(struct sock *sk, int pf, int val,
char __user *opt, int *len, int get)
{
struct nf_sockopt_ops *ops;
int ret;
ops = nf_sockopt_find(sk, pf, val, get);
if (IS_ERR(ops))
return PTR_ERR(ops);
if (get) {
if (ops->compat_get)
ret = ops->compat_get(sk, val, opt, len);
else
ret = ops->get(sk, val, opt, len);
} else {
if (ops->compat_set)
ret = ops->compat_set(sk, val, opt, *len);
else
ret = ops->set(sk, val, opt, *len);
}
module_put(ops->owner);
return ret;
}
int compat_nf_setsockopt(struct sock *sk, int pf,
int val, char __user *opt, int len)
{
return compat_nf_sockopt(sk, pf, val, opt, &len, 0);
}
EXPORT_SYMBOL(compat_nf_setsockopt);
int compat_nf_getsockopt(struct sock *sk, int pf,
int val, char __user *opt, int *len)
{
return compat_nf_sockopt(sk, pf, val, opt, len, 1);
}
EXPORT_SYMBOL(compat_nf_getsockopt);
#endif
|
