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 32 static struct list_head * 33 net_ctl_header_lookup(struct ctl_table_root *root, struct nsproxy *namespaces) 34 { 35 return &namespaces->net_ns->sysctl_table_headers; 36 } 37 38 static struct ctl_table_root net_sysctl_root = { 39 .lookup = net_ctl_header_lookup, 40 }; 41 42 static LIST_HEAD(net_sysctl_ro_tables); 43 static struct list_head *net_ctl_ro_header_lookup(struct ctl_table_root *root, 44 struct nsproxy *namespaces) 45 { 46 return &net_sysctl_ro_tables; 47 } 48 49 static int net_ctl_ro_header_perms(struct ctl_table_root *root, 50 struct nsproxy *namespaces, struct ctl_table *table) 51 { 52 if (namespaces->net_ns == &init_net) 53 return table->mode; 54 else 55 return table->mode & ~0222; 56 } 57 58 static struct ctl_table_root net_sysctl_ro_root = { 59 .lookup = net_ctl_ro_header_lookup, 60 .permissions = net_ctl_ro_header_perms, 61 }; 62 63 static int sysctl_net_init(struct net *net) 64 { 65 INIT_LIST_HEAD(&net->sysctl_table_headers); 66 return 0; 67 } 68 69 static void sysctl_net_exit(struct net *net) 70 { 71 WARN_ON(!list_empty(&net->sysctl_table_headers)); 72 return; 73 } 74 75 static struct pernet_operations sysctl_pernet_ops = { 76 .init = sysctl_net_init, 77 .exit = sysctl_net_exit, 78 }; 79 80 static __init int sysctl_init(void) 81 { 82 int ret; 83 ret = register_pernet_subsys(&sysctl_pernet_ops); 84 if (ret) 85 goto out; 86 register_sysctl_root(&net_sysctl_root); 87 register_sysctl_root(&net_sysctl_ro_root); 88 out: 89 return ret; 90 } 91 subsys_initcall(sysctl_init); 92 93 struct ctl_table_header *register_net_sysctl_table(struct net *net, 94 const struct ctl_path *path, struct ctl_table *table) 95 { 96 struct nsproxy namespaces; 97 namespaces = *current->nsproxy; 98 namespaces.net_ns = net; 99 return __register_sysctl_paths(&net_sysctl_root, 100 &namespaces, path, table); 101 } 102 EXPORT_SYMBOL_GPL(register_net_sysctl_table); 103 104 struct ctl_table_header *register_net_sysctl_rotable(const 105 struct ctl_path *path, struct ctl_table *table) 106 { 107 return __register_sysctl_paths(&net_sysctl_ro_root, 108 &init_nsproxy, path, table); 109 } 110 EXPORT_SYMBOL_GPL(register_net_sysctl_rotable); 111 112 void unregister_net_sysctl_table(struct ctl_table_header *header) 113 { 114 unregister_sysctl_table(header); 115 } 116 EXPORT_SYMBOL_GPL(unregister_net_sysctl_table); 117