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