1 /* 2 * Operations on the network namespace 3 */ 4 #ifndef __NET_NET_NAMESPACE_H 5 #define __NET_NET_NAMESPACE_H 6 7 #include <asm/atomic.h> 8 #include <linux/workqueue.h> 9 #include <linux/list.h> 10 11 #include <net/netns/core.h> 12 #include <net/netns/mib.h> 13 #include <net/netns/unix.h> 14 #include <net/netns/packet.h> 15 #include <net/netns/ipv4.h> 16 #include <net/netns/ipv6.h> 17 #include <net/netns/dccp.h> 18 #include <net/netns/x_tables.h> 19 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) 20 #include <net/netns/conntrack.h> 21 #endif 22 #include <net/netns/xfrm.h> 23 24 struct proc_dir_entry; 25 struct net_device; 26 struct sock; 27 struct ctl_table_header; 28 struct net_generic; 29 struct sock; 30 31 32 #define NETDEV_HASHBITS 8 33 #define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS) 34 35 struct net { 36 atomic_t count; /* To decided when the network 37 * namespace should be freed. 38 */ 39 #ifdef NETNS_REFCNT_DEBUG 40 atomic_t use_count; /* To track references we 41 * destroy on demand 42 */ 43 #endif 44 struct list_head list; /* list of network namespaces */ 45 struct list_head cleanup_list; /* namespaces on death row */ 46 struct list_head exit_list; /* Use only net_mutex */ 47 48 struct proc_dir_entry *proc_net; 49 struct proc_dir_entry *proc_net_stat; 50 51 #ifdef CONFIG_SYSCTL 52 struct ctl_table_set sysctls; 53 #endif 54 55 struct net_device *loopback_dev; /* The loopback */ 56 57 struct list_head dev_base_head; 58 struct hlist_head *dev_name_head; 59 struct hlist_head *dev_index_head; 60 61 /* core fib_rules */ 62 struct list_head rules_ops; 63 spinlock_t rules_mod_lock; 64 65 struct sock *rtnl; /* rtnetlink socket */ 66 struct sock *genl_sock; 67 68 struct netns_core core; 69 struct netns_mib mib; 70 struct netns_packet packet; 71 struct netns_unix unx; 72 struct netns_ipv4 ipv4; 73 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 74 struct netns_ipv6 ipv6; 75 #endif 76 #if defined(CONFIG_IP_DCCP) || defined(CONFIG_IP_DCCP_MODULE) 77 struct netns_dccp dccp; 78 #endif 79 #ifdef CONFIG_NETFILTER 80 struct netns_xt xt; 81 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) 82 struct netns_ct ct; 83 #endif 84 #endif 85 #ifdef CONFIG_XFRM 86 struct netns_xfrm xfrm; 87 #endif 88 #ifdef CONFIG_WEXT_CORE 89 struct sk_buff_head wext_nlevents; 90 #endif 91 struct net_generic *gen; 92 }; 93 94 95 #include <linux/seq_file_net.h> 96 97 /* Init's network namespace */ 98 extern struct net init_net; 99 100 #ifdef CONFIG_NET 101 #define INIT_NET_NS(net_ns) .net_ns = &init_net, 102 103 extern struct net *copy_net_ns(unsigned long flags, struct net *net_ns); 104 105 #else /* CONFIG_NET */ 106 107 #define INIT_NET_NS(net_ns) 108 109 static inline struct net *copy_net_ns(unsigned long flags, struct net *net_ns) 110 { 111 /* There is nothing to copy so this is a noop */ 112 return net_ns; 113 } 114 #endif /* CONFIG_NET */ 115 116 117 extern struct list_head net_namespace_list; 118 119 extern struct net *get_net_ns_by_pid(pid_t pid); 120 121 #ifdef CONFIG_NET_NS 122 extern void __put_net(struct net *net); 123 124 static inline struct net *get_net(struct net *net) 125 { 126 atomic_inc(&net->count); 127 return net; 128 } 129 130 static inline struct net *maybe_get_net(struct net *net) 131 { 132 /* Used when we know struct net exists but we 133 * aren't guaranteed a previous reference count 134 * exists. If the reference count is zero this 135 * function fails and returns NULL. 136 */ 137 if (!atomic_inc_not_zero(&net->count)) 138 net = NULL; 139 return net; 140 } 141 142 static inline void put_net(struct net *net) 143 { 144 if (atomic_dec_and_test(&net->count)) 145 __put_net(net); 146 } 147 148 static inline 149 int net_eq(const struct net *net1, const struct net *net2) 150 { 151 return net1 == net2; 152 } 153 #else 154 155 static inline struct net *get_net(struct net *net) 156 { 157 return net; 158 } 159 160 static inline void put_net(struct net *net) 161 { 162 } 163 164 static inline struct net *maybe_get_net(struct net *net) 165 { 166 return net; 167 } 168 169 static inline 170 int net_eq(const struct net *net1, const struct net *net2) 171 { 172 return 1; 173 } 174 #endif 175 176 177 #ifdef NETNS_REFCNT_DEBUG 178 static inline struct net *hold_net(struct net *net) 179 { 180 if (net) 181 atomic_inc(&net->use_count); 182 return net; 183 } 184 185 static inline void release_net(struct net *net) 186 { 187 if (net) 188 atomic_dec(&net->use_count); 189 } 190 #else 191 static inline struct net *hold_net(struct net *net) 192 { 193 return net; 194 } 195 196 static inline void release_net(struct net *net) 197 { 198 } 199 #endif 200 201 #ifdef CONFIG_NET_NS 202 203 static inline void write_pnet(struct net **pnet, struct net *net) 204 { 205 *pnet = net; 206 } 207 208 static inline struct net *read_pnet(struct net * const *pnet) 209 { 210 return *pnet; 211 } 212 213 #else 214 215 #define write_pnet(pnet, net) do { (void)(net);} while (0) 216 #define read_pnet(pnet) (&init_net) 217 218 #endif 219 220 #define for_each_net(VAR) \ 221 list_for_each_entry(VAR, &net_namespace_list, list) 222 223 #define for_each_net_rcu(VAR) \ 224 list_for_each_entry_rcu(VAR, &net_namespace_list, list) 225 226 #ifdef CONFIG_NET_NS 227 #define __net_init 228 #define __net_exit 229 #define __net_initdata 230 #else 231 #define __net_init __init 232 #define __net_exit __exit_refok 233 #define __net_initdata __initdata 234 #endif 235 236 struct pernet_operations { 237 struct list_head list; 238 int (*init)(struct net *net); 239 void (*exit)(struct net *net); 240 void (*exit_batch)(struct list_head *net_exit_list); 241 int *id; 242 size_t size; 243 }; 244 245 /* 246 * Use these carefully. If you implement a network device and it 247 * needs per network namespace operations use device pernet operations, 248 * otherwise use pernet subsys operations. 249 * 250 * Network interfaces need to be removed from a dying netns _before_ 251 * subsys notifiers can be called, as most of the network code cleanup 252 * (which is done from subsys notifiers) runs with the assumption that 253 * dev_remove_pack has been called so no new packets will arrive during 254 * and after the cleanup functions have been called. dev_remove_pack 255 * is not per namespace so instead the guarantee of no more packets 256 * arriving in a network namespace is provided by ensuring that all 257 * network devices and all sockets have left the network namespace 258 * before the cleanup methods are called. 259 * 260 * For the longest time the ipv4 icmp code was registered as a pernet 261 * device which caused kernel oops, and panics during network 262 * namespace cleanup. So please don't get this wrong. 263 */ 264 extern int register_pernet_subsys(struct pernet_operations *); 265 extern void unregister_pernet_subsys(struct pernet_operations *); 266 extern int register_pernet_device(struct pernet_operations *); 267 extern void unregister_pernet_device(struct pernet_operations *); 268 269 struct ctl_path; 270 struct ctl_table; 271 struct ctl_table_header; 272 273 extern struct ctl_table_header *register_net_sysctl_table(struct net *net, 274 const struct ctl_path *path, struct ctl_table *table); 275 extern struct ctl_table_header *register_net_sysctl_rotable( 276 const struct ctl_path *path, struct ctl_table *table); 277 extern void unregister_net_sysctl_table(struct ctl_table_header *header); 278 279 #endif /* __NET_NET_NAMESPACE_H */ 280