Linux kernel mirror (for testing)
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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/sysctl.h>
16#include <linux/nsproxy.h>
17
18#include <net/sock.h>
19
20#ifdef CONFIG_INET
21#include <net/ip.h>
22#endif
23
24#ifdef CONFIG_NET
25#include <linux/if_ether.h>
26#endif
27
28#ifdef CONFIG_TR
29#include <linux/if_tr.h>
30#endif
31
32static struct ctl_table_set *
33net_ctl_header_lookup(struct ctl_table_root *root, struct nsproxy *namespaces)
34{
35 return &namespaces->net_ns->sysctls;
36}
37
38static int is_seen(struct ctl_table_set *set)
39{
40 return ¤t->nsproxy->net_ns->sysctls == set;
41}
42
43/* Return standard mode bits for table entry. */
44static int net_ctl_permissions(struct ctl_table_root *root,
45 struct nsproxy *nsproxy,
46 struct ctl_table *table)
47{
48 /* Allow network administrator to have same access as root. */
49 if (capable(CAP_NET_ADMIN)) {
50 int mode = (table->mode >> 6) & 7;
51 return (mode << 6) | (mode << 3) | mode;
52 }
53 return table->mode;
54}
55
56static struct ctl_table_root net_sysctl_root = {
57 .lookup = net_ctl_header_lookup,
58 .permissions = net_ctl_permissions,
59};
60
61static int net_ctl_ro_header_perms(struct ctl_table_root *root,
62 struct nsproxy *namespaces, struct ctl_table *table)
63{
64 if (net_eq(namespaces->net_ns, &init_net))
65 return table->mode;
66 else
67 return table->mode & ~0222;
68}
69
70static struct ctl_table_root net_sysctl_ro_root = {
71 .permissions = net_ctl_ro_header_perms,
72};
73
74static int __net_init sysctl_net_init(struct net *net)
75{
76 setup_sysctl_set(&net->sysctls,
77 &net_sysctl_ro_root.default_set,
78 is_seen);
79 return 0;
80}
81
82static void __net_exit sysctl_net_exit(struct net *net)
83{
84 WARN_ON(!list_empty(&net->sysctls.list));
85}
86
87static struct pernet_operations sysctl_pernet_ops = {
88 .init = sysctl_net_init,
89 .exit = sysctl_net_exit,
90};
91
92static __init int sysctl_init(void)
93{
94 int ret;
95 ret = register_pernet_subsys(&sysctl_pernet_ops);
96 if (ret)
97 goto out;
98 register_sysctl_root(&net_sysctl_root);
99 setup_sysctl_set(&net_sysctl_ro_root.default_set, NULL, NULL);
100 register_sysctl_root(&net_sysctl_ro_root);
101out:
102 return ret;
103}
104subsys_initcall(sysctl_init);
105
106struct ctl_table_header *register_net_sysctl_table(struct net *net,
107 const struct ctl_path *path, struct ctl_table *table)
108{
109 struct nsproxy namespaces;
110 namespaces = *current->nsproxy;
111 namespaces.net_ns = net;
112 return __register_sysctl_paths(&net_sysctl_root,
113 &namespaces, path, table);
114}
115EXPORT_SYMBOL_GPL(register_net_sysctl_table);
116
117struct ctl_table_header *register_net_sysctl_rotable(const
118 struct ctl_path *path, struct ctl_table *table)
119{
120 return __register_sysctl_paths(&net_sysctl_ro_root,
121 &init_nsproxy, path, table);
122}
123EXPORT_SYMBOL_GPL(register_net_sysctl_rotable);
124
125void unregister_net_sysctl_table(struct ctl_table_header *header)
126{
127 unregister_sysctl_table(header);
128}
129EXPORT_SYMBOL_GPL(unregister_net_sysctl_table);