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Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
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linux
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 list_head *
33net_ctl_header_lookup(struct ctl_table_root *root, struct nsproxy *namespaces)
34{
35 return &namespaces->net_ns->sysctl_table_headers;
36}
37
38/* Return standard mode bits for table entry. */
39static int net_ctl_permissions(struct ctl_table_root *root,
40 struct nsproxy *nsproxy,
41 struct ctl_table *table)
42{
43 /* Allow network administrator to have same access as root. */
44 if (capable(CAP_NET_ADMIN)) {
45 int mode = (table->mode >> 6) & 7;
46 return (mode << 6) | (mode << 3) | mode;
47 }
48 return table->mode;
49}
50
51static struct ctl_table_root net_sysctl_root = {
52 .lookup = net_ctl_header_lookup,
53 .permissions = net_ctl_permissions,
54};
55
56static LIST_HEAD(net_sysctl_ro_tables);
57static struct list_head *net_ctl_ro_header_lookup(struct ctl_table_root *root,
58 struct nsproxy *namespaces)
59{
60 return &net_sysctl_ro_tables;
61}
62
63static int net_ctl_ro_header_perms(struct ctl_table_root *root,
64 struct nsproxy *namespaces, struct ctl_table *table)
65{
66 if (namespaces->net_ns == &init_net)
67 return table->mode;
68 else
69 return table->mode & ~0222;
70}
71
72static struct ctl_table_root net_sysctl_ro_root = {
73 .lookup = net_ctl_ro_header_lookup,
74 .permissions = net_ctl_ro_header_perms,
75};
76
77static int sysctl_net_init(struct net *net)
78{
79 INIT_LIST_HEAD(&net->sysctl_table_headers);
80 return 0;
81}
82
83static void sysctl_net_exit(struct net *net)
84{
85 WARN_ON(!list_empty(&net->sysctl_table_headers));
86 return;
87}
88
89static struct pernet_operations sysctl_pernet_ops = {
90 .init = sysctl_net_init,
91 .exit = sysctl_net_exit,
92};
93
94static __init int sysctl_init(void)
95{
96 int ret;
97 ret = register_pernet_subsys(&sysctl_pernet_ops);
98 if (ret)
99 goto out;
100 register_sysctl_root(&net_sysctl_root);
101 register_sysctl_root(&net_sysctl_ro_root);
102out:
103 return ret;
104}
105subsys_initcall(sysctl_init);
106
107struct ctl_table_header *register_net_sysctl_table(struct net *net,
108 const struct ctl_path *path, struct ctl_table *table)
109{
110 struct nsproxy namespaces;
111 namespaces = *current->nsproxy;
112 namespaces.net_ns = net;
113 return __register_sysctl_paths(&net_sysctl_root,
114 &namespaces, path, table);
115}
116EXPORT_SYMBOL_GPL(register_net_sysctl_table);
117
118struct ctl_table_header *register_net_sysctl_rotable(const
119 struct ctl_path *path, struct ctl_table *table)
120{
121 return __register_sysctl_paths(&net_sysctl_ro_root,
122 &init_nsproxy, path, table);
123}
124EXPORT_SYMBOL_GPL(register_net_sysctl_rotable);
125
126void unregister_net_sysctl_table(struct ctl_table_header *header)
127{
128 unregister_sysctl_table(header);
129}
130EXPORT_SYMBOL_GPL(unregister_net_sysctl_table);