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