1 /* 2 * Operations on the network namespace 3 */ 4 #ifndef __NET_NET_NAMESPACE_H 5 #define __NET_NET_NAMESPACE_H 6 7 #include <linux/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 unsigned int dev_base_seq; /* protected by rtnl_mutex */ 69 70 /* core fib_rules */ 71 struct list_head rules_ops; 72 73 74 struct net_device *loopback_dev; /* The loopback */ 75 struct netns_core core; 76 struct netns_mib mib; 77 struct netns_packet packet; 78 struct netns_unix unx; 79 struct netns_ipv4 ipv4; 80 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 81 struct netns_ipv6 ipv6; 82 #endif 83 #if defined(CONFIG_IP_DCCP) || defined(CONFIG_IP_DCCP_MODULE) 84 struct netns_dccp dccp; 85 #endif 86 #ifdef CONFIG_NETFILTER 87 struct netns_xt xt; 88 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) 89 struct netns_ct ct; 90 #endif 91 struct sock *nfnl; 92 struct sock *nfnl_stash; 93 #endif 94 #ifdef CONFIG_WEXT_CORE 95 struct sk_buff_head wext_nlevents; 96 #endif 97 struct net_generic __rcu *gen; 98 99 /* Note : following structs are cache line aligned */ 100 #ifdef CONFIG_XFRM 101 struct netns_xfrm xfrm; 102 #endif 103 struct netns_ipvs *ipvs; 104 }; 105 106 107 #include <linux/seq_file_net.h> 108 109 /* Init's network namespace */ 110 extern struct net init_net; 111 112 #ifdef CONFIG_NET 113 extern struct net *copy_net_ns(unsigned long flags, struct net *net_ns); 114 115 #else /* CONFIG_NET */ 116 static inline struct net *copy_net_ns(unsigned long flags, struct net *net_ns) 117 { 118 /* There is nothing to copy so this is a noop */ 119 return net_ns; 120 } 121 #endif /* CONFIG_NET */ 122 123 124 extern struct list_head net_namespace_list; 125 126 extern struct net *get_net_ns_by_pid(pid_t pid); 127 extern struct net *get_net_ns_by_fd(int pid); 128 129 #ifdef CONFIG_NET_NS 130 extern void __put_net(struct net *net); 131 132 static inline struct net *get_net(struct net *net) 133 { 134 atomic_inc(&net->count); 135 return net; 136 } 137 138 static inline struct net *maybe_get_net(struct net *net) 139 { 140 /* Used when we know struct net exists but we 141 * aren't guaranteed a previous reference count 142 * exists. If the reference count is zero this 143 * function fails and returns NULL. 144 */ 145 if (!atomic_inc_not_zero(&net->count)) 146 net = NULL; 147 return net; 148 } 149 150 static inline void put_net(struct net *net) 151 { 152 if (atomic_dec_and_test(&net->count)) 153 __put_net(net); 154 } 155 156 static inline 157 int net_eq(const struct net *net1, const struct net *net2) 158 { 159 return net1 == net2; 160 } 161 162 extern void net_drop_ns(void *); 163 164 #else 165 166 static inline struct net *get_net(struct net *net) 167 { 168 return net; 169 } 170 171 static inline void put_net(struct net *net) 172 { 173 } 174 175 static inline struct net *maybe_get_net(struct net *net) 176 { 177 return net; 178 } 179 180 static inline 181 int net_eq(const struct net *net1, const struct net *net2) 182 { 183 return 1; 184 } 185 186 #define net_drop_ns NULL 187 #endif 188 189 190 #ifdef NETNS_REFCNT_DEBUG 191 static inline struct net *hold_net(struct net *net) 192 { 193 if (net) 194 atomic_inc(&net->use_count); 195 return net; 196 } 197 198 static inline void release_net(struct net *net) 199 { 200 if (net) 201 atomic_dec(&net->use_count); 202 } 203 #else 204 static inline struct net *hold_net(struct net *net) 205 { 206 return net; 207 } 208 209 static inline void release_net(struct net *net) 210 { 211 } 212 #endif 213 214 #ifdef CONFIG_NET_NS 215 216 static inline void write_pnet(struct net **pnet, struct net *net) 217 { 218 *pnet = net; 219 } 220 221 static inline struct net *read_pnet(struct net * const *pnet) 222 { 223 return *pnet; 224 } 225 226 #else 227 228 #define write_pnet(pnet, net) do { (void)(net);} while (0) 229 #define read_pnet(pnet) (&init_net) 230 231 #endif 232 233 #define for_each_net(VAR) \ 234 list_for_each_entry(VAR, &net_namespace_list, list) 235 236 #define for_each_net_rcu(VAR) \ 237 list_for_each_entry_rcu(VAR, &net_namespace_list, list) 238 239 #ifdef CONFIG_NET_NS 240 #define __net_init 241 #define __net_exit 242 #define __net_initdata 243 #else 244 #define __net_init __init 245 #define __net_exit __exit_refok 246 #define __net_initdata __initdata 247 #endif 248 249 struct pernet_operations { 250 struct list_head list; 251 int (*init)(struct net *net); 252 void (*exit)(struct net *net); 253 void (*exit_batch)(struct list_head *net_exit_list); 254 int *id; 255 size_t size; 256 }; 257 258 /* 259 * Use these carefully. If you implement a network device and it 260 * needs per network namespace operations use device pernet operations, 261 * otherwise use pernet subsys operations. 262 * 263 * Network interfaces need to be removed from a dying netns _before_ 264 * subsys notifiers can be called, as most of the network code cleanup 265 * (which is done from subsys notifiers) runs with the assumption that 266 * dev_remove_pack has been called so no new packets will arrive during 267 * and after the cleanup functions have been called. dev_remove_pack 268 * is not per namespace so instead the guarantee of no more packets 269 * arriving in a network namespace is provided by ensuring that all 270 * network devices and all sockets have left the network namespace 271 * before the cleanup methods are called. 272 * 273 * For the longest time the ipv4 icmp code was registered as a pernet 274 * device which caused kernel oops, and panics during network 275 * namespace cleanup. So please don't get this wrong. 276 */ 277 extern int register_pernet_subsys(struct pernet_operations *); 278 extern void unregister_pernet_subsys(struct pernet_operations *); 279 extern int register_pernet_device(struct pernet_operations *); 280 extern void unregister_pernet_device(struct pernet_operations *); 281 282 struct ctl_path; 283 struct ctl_table; 284 struct ctl_table_header; 285 286 extern struct ctl_table_header *register_net_sysctl_table(struct net *net, 287 const struct ctl_path *path, struct ctl_table *table); 288 extern struct ctl_table_header *register_net_sysctl_rotable( 289 const struct ctl_path *path, struct ctl_table *table); 290 extern void unregister_net_sysctl_table(struct ctl_table_header *header); 291 292 #endif /* __NET_NET_NAMESPACE_H */ 293