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