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 #include <linux/sysctl.h> 11 12 #include <net/netns/core.h> 13 #include <net/netns/mib.h> 14 #include <net/netns/unix.h> 15 #include <net/netns/packet.h> 16 #include <net/netns/ipv4.h> 17 #include <net/netns/ipv6.h> 18 #include <net/netns/dccp.h> 19 #include <net/netns/x_tables.h> 20 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) 21 #include <net/netns/conntrack.h> 22 #endif 23 #include <net/netns/xfrm.h> 24 25 struct proc_dir_entry; 26 struct net_device; 27 struct sock; 28 struct ctl_table_header; 29 struct net_generic; 30 struct sock; 31 struct netns_ipvs; 32 33 34 #define NETDEV_HASHBITS 8 35 #define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS) 36 37 struct net { 38 atomic_t passive; /* To decided when the network 39 * namespace should be freed. 40 */ 41 atomic_t count; /* To decided when the network 42 * namespace should be shut down. 43 */ 44 #ifdef NETNS_REFCNT_DEBUG 45 atomic_t use_count; /* To track references we 46 * destroy on demand 47 */ 48 #endif 49 spinlock_t rules_mod_lock; 50 51 struct list_head list; /* list of network namespaces */ 52 struct list_head cleanup_list; /* namespaces on death row */ 53 struct list_head exit_list; /* Use only net_mutex */ 54 55 struct proc_dir_entry *proc_net; 56 struct proc_dir_entry *proc_net_stat; 57 58 #ifdef CONFIG_SYSCTL 59 struct ctl_table_set sysctls; 60 #endif 61 62 struct sock *rtnl; /* rtnetlink socket */ 63 struct sock *genl_sock; 64 65 struct list_head dev_base_head; 66 struct hlist_head *dev_name_head; 67 struct hlist_head *dev_index_head; 68 69 /* core fib_rules */ 70 struct list_head rules_ops; 71 72 73 struct net_device *loopback_dev; /* The loopback */ 74 struct netns_core core; 75 struct netns_mib mib; 76 struct netns_packet packet; 77 struct netns_unix unx; 78 struct netns_ipv4 ipv4; 79 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 80 struct netns_ipv6 ipv6; 81 #endif 82 #if defined(CONFIG_IP_DCCP) || defined(CONFIG_IP_DCCP_MODULE) 83 struct netns_dccp dccp; 84 #endif 85 #ifdef CONFIG_NETFILTER 86 struct netns_xt xt; 87 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) 88 struct netns_ct ct; 89 #endif 90 struct sock *nfnl; 91 struct sock *nfnl_stash; 92 #endif 93 #ifdef CONFIG_WEXT_CORE 94 struct sk_buff_head wext_nlevents; 95 #endif 96 struct net_generic __rcu *gen; 97 98 /* Note : following structs are cache line aligned */ 99 #ifdef CONFIG_XFRM 100 struct netns_xfrm xfrm; 101 #endif 102 struct netns_ipvs *ipvs; 103 }; 104 105 106 #include <linux/seq_file_net.h> 107 108 /* Init's network namespace */ 109 extern struct net init_net; 110 111 #ifdef CONFIG_NET 112 extern struct net *copy_net_ns(unsigned long flags, struct net *net_ns); 113 114 #else /* CONFIG_NET */ 115 static inline struct net *copy_net_ns(unsigned long flags, struct net *net_ns) 116 { 117 /* There is nothing to copy so this is a noop */ 118 return net_ns; 119 } 120 #endif /* CONFIG_NET */ 121 122 123 extern struct list_head net_namespace_list; 124 125 extern struct net *get_net_ns_by_pid(pid_t pid); 126 extern struct net *get_net_ns_by_fd(int pid); 127 128 #ifdef CONFIG_NET_NS 129 extern void __put_net(struct net *net); 130 131 static inline struct net *get_net(struct net *net) 132 { 133 atomic_inc(&net->count); 134 return net; 135 } 136 137 static inline struct net *maybe_get_net(struct net *net) 138 { 139 /* Used when we know struct net exists but we 140 * aren't guaranteed a previous reference count 141 * exists. If the reference count is zero this 142 * function fails and returns NULL. 143 */ 144 if (!atomic_inc_not_zero(&net->count)) 145 net = NULL; 146 return net; 147 } 148 149 static inline void put_net(struct net *net) 150 { 151 if (atomic_dec_and_test(&net->count)) 152 __put_net(net); 153 } 154 155 static inline 156 int net_eq(const struct net *net1, const struct net *net2) 157 { 158 return net1 == net2; 159 } 160 161 extern void net_drop_ns(void *); 162 163 #else 164 165 static inline struct net *get_net(struct net *net) 166 { 167 return net; 168 } 169 170 static inline void put_net(struct net *net) 171 { 172 } 173 174 static inline struct net *maybe_get_net(struct net *net) 175 { 176 return net; 177 } 178 179 static inline 180 int net_eq(const struct net *net1, const struct net *net2) 181 { 182 return 1; 183 } 184 185 #define net_drop_ns NULL 186 #endif 187 188 189 #ifdef NETNS_REFCNT_DEBUG 190 static inline struct net *hold_net(struct net *net) 191 { 192 if (net) 193 atomic_inc(&net->use_count); 194 return net; 195 } 196 197 static inline void release_net(struct net *net) 198 { 199 if (net) 200 atomic_dec(&net->use_count); 201 } 202 #else 203 static inline struct net *hold_net(struct net *net) 204 { 205 return net; 206 } 207 208 static inline void release_net(struct net *net) 209 { 210 } 211 #endif 212 213 #ifdef CONFIG_NET_NS 214 215 static inline void write_pnet(struct net **pnet, struct net *net) 216 { 217 *pnet = net; 218 } 219 220 static inline struct net *read_pnet(struct net * const *pnet) 221 { 222 return *pnet; 223 } 224 225 #else 226 227 #define write_pnet(pnet, net) do { (void)(net);} while (0) 228 #define read_pnet(pnet) (&init_net) 229 230 #endif 231 232 #define for_each_net(VAR) \ 233 list_for_each_entry(VAR, &net_namespace_list, list) 234 235 #define for_each_net_rcu(VAR) \ 236 list_for_each_entry_rcu(VAR, &net_namespace_list, list) 237 238 #ifdef CONFIG_NET_NS 239 #define __net_init 240 #define __net_exit 241 #define __net_initdata 242 #else 243 #define __net_init __init 244 #define __net_exit __exit_refok 245 #define __net_initdata __initdata 246 #endif 247 248 struct pernet_operations { 249 struct list_head list; 250 int (*init)(struct net *net); 251 void (*exit)(struct net *net); 252 void (*exit_batch)(struct list_head *net_exit_list); 253 int *id; 254 size_t size; 255 }; 256 257 /* 258 * Use these carefully. If you implement a network device and it 259 * needs per network namespace operations use device pernet operations, 260 * otherwise use pernet subsys operations. 261 * 262 * Network interfaces need to be removed from a dying netns _before_ 263 * subsys notifiers can be called, as most of the network code cleanup 264 * (which is done from subsys notifiers) runs with the assumption that 265 * dev_remove_pack has been called so no new packets will arrive during 266 * and after the cleanup functions have been called. dev_remove_pack 267 * is not per namespace so instead the guarantee of no more packets 268 * arriving in a network namespace is provided by ensuring that all 269 * network devices and all sockets have left the network namespace 270 * before the cleanup methods are called. 271 * 272 * For the longest time the ipv4 icmp code was registered as a pernet 273 * device which caused kernel oops, and panics during network 274 * namespace cleanup. So please don't get this wrong. 275 */ 276 extern int register_pernet_subsys(struct pernet_operations *); 277 extern void unregister_pernet_subsys(struct pernet_operations *); 278 extern int register_pernet_device(struct pernet_operations *); 279 extern void unregister_pernet_device(struct pernet_operations *); 280 281 struct ctl_path; 282 struct ctl_table; 283 struct ctl_table_header; 284 285 extern struct ctl_table_header *register_net_sysctl_table(struct net *net, 286 const struct ctl_path *path, struct ctl_table *table); 287 extern struct ctl_table_header *register_net_sysctl_rotable( 288 const struct ctl_path *path, struct ctl_table *table); 289 extern void unregister_net_sysctl_table(struct ctl_table_header *header); 290 291 #endif /* __NET_NET_NAMESPACE_H */ 292