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1/* -*- linux-c -*-
2 * sysctl_net.c: sysctl interface to net subsystem.
3 *
4 * Begun April 1, 1996, Mike Shaver.
5 * Added /proc/sys/net directories for each protocol family. [MS]
6 *
7 * Revision 1.2 1996/05/08 20:24:40 shaver
8 * Added bits for NET_BRIDGE and the NET_IPV4_ARP stuff and
9 * NET_IPV4_IP_FORWARD.
10 *
11 *
12 */
13
14#include <linux/mm.h>
15#include <linux/export.h>
16#include <linux/sysctl.h>
17#include <linux/nsproxy.h>
18
19#include <net/sock.h>
20
21#ifdef CONFIG_INET
22#include <net/ip.h>
23#endif
24
25#ifdef CONFIG_NET
26#include <linux/if_ether.h>
27#endif
28
29#ifdef CONFIG_TR
30#include <linux/if_tr.h>
31#endif
32
33static struct ctl_table_set *
34net_ctl_header_lookup(struct ctl_table_root *root, struct nsproxy *namespaces)
35{
36 return &namespaces->net_ns->sysctls;
37}
38
39static int is_seen(struct ctl_table_set *set)
40{
41 return ¤t->nsproxy->net_ns->sysctls == set;
42}
43
44/* Return standard mode bits for table entry. */
45static int net_ctl_permissions(struct ctl_table_root *root,
46 struct nsproxy *nsproxy,
47 struct ctl_table *table)
48{
49 /* Allow network administrator to have same access as root. */
50 if (capable(CAP_NET_ADMIN)) {
51 int mode = (table->mode >> 6) & 7;
52 return (mode << 6) | (mode << 3) | mode;
53 }
54 return table->mode;
55}
56
57static struct ctl_table_root net_sysctl_root = {
58 .lookup = net_ctl_header_lookup,
59 .permissions = net_ctl_permissions,
60};
61
62static int net_ctl_ro_header_perms(struct ctl_table_root *root,
63 struct nsproxy *namespaces, struct ctl_table *table)
64{
65 if (net_eq(namespaces->net_ns, &init_net))
66 return table->mode;
67 else
68 return table->mode & ~0222;
69}
70
71static struct ctl_table_root net_sysctl_ro_root = {
72 .permissions = net_ctl_ro_header_perms,
73};
74
75static int __net_init sysctl_net_init(struct net *net)
76{
77 setup_sysctl_set(&net->sysctls, &net_sysctl_root, is_seen);
78 return 0;
79}
80
81static void __net_exit sysctl_net_exit(struct net *net)
82{
83 retire_sysctl_set(&net->sysctls);
84}
85
86static struct pernet_operations sysctl_pernet_ops = {
87 .init = sysctl_net_init,
88 .exit = sysctl_net_exit,
89};
90
91static __init int net_sysctl_init(void)
92{
93 int ret;
94 ret = register_pernet_subsys(&sysctl_pernet_ops);
95 if (ret)
96 goto out;
97 setup_sysctl_set(&net_sysctl_ro_root.default_set, &net_sysctl_ro_root, NULL);
98 register_sysctl_root(&net_sysctl_ro_root);
99 register_sysctl_root(&net_sysctl_root);
100out:
101 return ret;
102}
103subsys_initcall(net_sysctl_init);
104
105struct ctl_table_header *register_net_sysctl_table(struct net *net,
106 const struct ctl_path *path, struct ctl_table *table)
107{
108 return __register_sysctl_paths(&net->sysctls, path, table);
109}
110EXPORT_SYMBOL_GPL(register_net_sysctl_table);
111
112struct ctl_table_header *register_net_sysctl_rotable(const
113 struct ctl_path *path, struct ctl_table *table)
114{
115 return __register_sysctl_paths(&net_sysctl_ro_root.default_set,
116 path, table);
117}
118EXPORT_SYMBOL_GPL(register_net_sysctl_rotable);
119
120void unregister_net_sysctl_table(struct ctl_table_header *header)
121{
122 unregister_sysctl_table(header);
123}
124EXPORT_SYMBOL_GPL(unregister_net_sysctl_table);