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