2 * sysctl_net.c: sysctl interface to net subsystem.
4 * Begun April 1, 1996, Mike Shaver.
5 * Added /proc/sys/net directories for each protocol family. [MS]
7 * Revision 1.2 1996/05/08 20:24:40 shaver
8 * Added bits for NET_BRIDGE and the NET_IPV4_ARP stuff and
15 #include <linux/export.h>
16 #include <linux/sysctl.h>
17 #include <linux/nsproxy.h>
26 #include <linux/if_ether.h>
29 static struct ctl_table_set *
30 net_ctl_header_lookup(struct ctl_table_root *root)
32 return ¤t->nsproxy->net_ns->sysctls;
35 static int is_seen(struct ctl_table_set *set)
37 return ¤t->nsproxy->net_ns->sysctls == set;
40 /* Return standard mode bits for table entry. */
41 static int net_ctl_permissions(struct ctl_table_header *head,
42 struct ctl_table *table)
44 struct net *net = container_of(head->set, struct net, sysctls);
46 /* Allow network administrator to have same access as root. */
47 if (ns_capable_noaudit(net->user_ns, CAP_NET_ADMIN)) {
48 int mode = (table->mode >> 6) & 7;
49 return (mode << 6) | (mode << 3) | mode;
55 static void net_ctl_set_ownership(struct ctl_table_header *head,
56 struct ctl_table *table,
57 kuid_t *uid, kgid_t *gid)
59 struct net *net = container_of(head->set, struct net, sysctls);
63 ns_root_uid = make_kuid(net->user_ns, 0);
64 if (uid_valid(ns_root_uid))
67 ns_root_gid = make_kgid(net->user_ns, 0);
68 if (gid_valid(ns_root_gid))
72 static struct ctl_table_root net_sysctl_root = {
73 .lookup = net_ctl_header_lookup,
74 .permissions = net_ctl_permissions,
75 .set_ownership = net_ctl_set_ownership,
78 static int __net_init sysctl_net_init(struct net *net)
80 setup_sysctl_set(&net->sysctls, &net_sysctl_root, is_seen);
84 static void __net_exit sysctl_net_exit(struct net *net)
86 retire_sysctl_set(&net->sysctls);
89 static struct pernet_operations sysctl_pernet_ops = {
90 .init = sysctl_net_init,
91 .exit = sysctl_net_exit,
94 static struct ctl_table_header *net_header;
95 __init int net_sysctl_init(void)
97 static struct ctl_table empty[1];
99 /* Avoid limitations in the sysctl implementation by
100 * registering "/proc/sys/net" as an empty directory not in a
103 net_header = register_sysctl("net", empty);
106 ret = register_pernet_subsys(&sysctl_pernet_ops);
112 unregister_sysctl_table(net_header);
117 struct ctl_table_header *register_net_sysctl(struct net *net,
118 const char *path, struct ctl_table *table)
120 return __register_sysctl_table(&net->sysctls, path, table);
122 EXPORT_SYMBOL_GPL(register_net_sysctl);
124 void unregister_net_sysctl_table(struct ctl_table_header *header)
126 unregister_sysctl_table(header);
128 EXPORT_SYMBOL_GPL(unregister_net_sysctl_table);