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); 122 123 #ifdef CONFIG_NET_NS 124 extern void __put_net(struct net *net); 125 126 static inline struct net *get_net(struct net *net) 127 { 128 atomic_inc(&net->count); 129 return net; 130 } 131 132 static inline struct net *maybe_get_net(struct net *net) 133 { 134 /* Used when we know struct net exists but we 135 * aren't guaranteed a previous reference count 136 * exists. If the reference count is zero this 137 * function fails and returns NULL. 138 */ 139 if (!atomic_inc_not_zero(&net->count)) 140 net = NULL; 141 return net; 142 } 143 144 static inline void put_net(struct net *net) 145 { 146 if (atomic_dec_and_test(&net->count)) 147 __put_net(net); 148 } 149 150 static inline 151 int net_eq(const struct net *net1, const struct net *net2) 152 { 153 return net1 == net2; 154 } 155 #else 156 157 static inline struct net *get_net(struct net *net) 158 { 159 return net; 160 } 161 162 static inline void put_net(struct net *net) 163 { 164 } 165 166 static inline struct net *maybe_get_net(struct net *net) 167 { 168 return net; 169 } 170 171 static inline 172 int net_eq(const struct net *net1, const struct net *net2) 173 { 174 return 1; 175 } 176 #endif 177 178 179 #ifdef NETNS_REFCNT_DEBUG 180 static inline struct net *hold_net(struct net *net) 181 { 182 if (net) 183 atomic_inc(&net->use_count); 184 return net; 185 } 186 187 static inline void release_net(struct net *net) 188 { 189 if (net) 190 atomic_dec(&net->use_count); 191 } 192 #else 193 static inline struct net *hold_net(struct net *net) 194 { 195 return net; 196 } 197 198 static inline void release_net(struct net *net) 199 { 200 } 201 #endif 202 203 #ifdef CONFIG_NET_NS 204 205 static inline void write_pnet(struct net **pnet, struct net *net) 206 { 207 *pnet = net; 208 } 209 210 static inline struct net *read_pnet(struct net * const *pnet) 211 { 212 return *pnet; 213 } 214 215 #else 216 217 #define write_pnet(pnet, net) do { (void)(net);} while (0) 218 #define read_pnet(pnet) (&init_net) 219 220 #endif 221 222 #define for_each_net(VAR) \ 223 list_for_each_entry(VAR, &net_namespace_list, list) 224 225 #define for_each_net_rcu(VAR) \ 226 list_for_each_entry_rcu(VAR, &net_namespace_list, list) 227 228 #ifdef CONFIG_NET_NS 229 #define __net_init 230 #define __net_exit 231 #define __net_initdata 232 #else 233 #define __net_init __init 234 #define __net_exit __exit_refok 235 #define __net_initdata __initdata 236 #endif 237 238 struct pernet_operations { 239 struct list_head list; 240 int (*init)(struct net *net); 241 void (*exit)(struct net *net); 242 void (*exit_batch)(struct list_head *net_exit_list); 243 int *id; 244 size_t size; 245 }; 246 247 /* 248 * Use these carefully. If you implement a network device and it 249 * needs per network namespace operations use device pernet operations, 250 * otherwise use pernet subsys operations. 251 * 252 * Network interfaces need to be removed from a dying netns _before_ 253 * subsys notifiers can be called, as most of the network code cleanup 254 * (which is done from subsys notifiers) runs with the assumption that 255 * dev_remove_pack has been called so no new packets will arrive during 256 * and after the cleanup functions have been called. dev_remove_pack 257 * is not per namespace so instead the guarantee of no more packets 258 * arriving in a network namespace is provided by ensuring that all 259 * network devices and all sockets have left the network namespace 260 * before the cleanup methods are called. 261 * 262 * For the longest time the ipv4 icmp code was registered as a pernet 263 * device which caused kernel oops, and panics during network 264 * namespace cleanup. So please don't get this wrong. 265 */ 266 extern int register_pernet_subsys(struct pernet_operations *); 267 extern void unregister_pernet_subsys(struct pernet_operations *); 268 extern int register_pernet_device(struct pernet_operations *); 269 extern void unregister_pernet_device(struct pernet_operations *); 270 271 struct ctl_path; 272 struct ctl_table; 273 struct ctl_table_header; 274 275 extern struct ctl_table_header *register_net_sysctl_table(struct net *net, 276 const struct ctl_path *path, struct ctl_table *table); 277 extern struct ctl_table_header *register_net_sysctl_rotable( 278 const struct ctl_path *path, struct ctl_table *table); 279 extern void unregister_net_sysctl_table(struct ctl_table_header *header); 280 281 #endif /* __NET_NET_NAMESPACE_H */ 282