1 /* 2 * Operations on the network namespace 3 */ 4 #ifndef __NET_NET_NAMESPACE_H 5 #define __NET_NET_NAMESPACE_H 6 7 #include <linux/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/sctp.h> 19 #include <net/netns/dccp.h> 20 #include <net/netns/x_tables.h> 21 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) 22 #include <net/netns/conntrack.h> 23 #endif 24 #include <net/netns/xfrm.h> 25 26 struct user_namespace; 27 struct proc_dir_entry; 28 struct net_device; 29 struct sock; 30 struct ctl_table_header; 31 struct net_generic; 32 struct sock; 33 struct netns_ipvs; 34 35 36 #define NETDEV_HASHBITS 8 37 #define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS) 38 39 struct net { 40 atomic_t passive; /* To decided when the network 41 * namespace should be freed. 42 */ 43 atomic_t count; /* To decided when the network 44 * namespace should be shut down. 45 */ 46 #ifdef NETNS_REFCNT_DEBUG 47 atomic_t use_count; /* To track references we 48 * destroy on demand 49 */ 50 #endif 51 spinlock_t rules_mod_lock; 52 53 struct list_head list; /* list of network namespaces */ 54 struct list_head cleanup_list; /* namespaces on death row */ 55 struct list_head exit_list; /* Use only net_mutex */ 56 57 struct user_namespace *user_ns; /* Owning user namespace */ 58 59 unsigned int proc_inum; 60 61 struct proc_dir_entry *proc_net; 62 struct proc_dir_entry *proc_net_stat; 63 64 #ifdef CONFIG_SYSCTL 65 struct ctl_table_set sysctls; 66 #endif 67 68 struct sock *rtnl; /* rtnetlink socket */ 69 struct sock *genl_sock; 70 71 struct list_head dev_base_head; 72 struct hlist_head *dev_name_head; 73 struct hlist_head *dev_index_head; 74 unsigned int dev_base_seq; /* protected by rtnl_mutex */ 75 int ifindex; 76 77 /* core fib_rules */ 78 struct list_head rules_ops; 79 80 81 struct net_device *loopback_dev; /* The loopback */ 82 struct netns_core core; 83 struct netns_mib mib; 84 struct netns_packet packet; 85 struct netns_unix unx; 86 struct netns_ipv4 ipv4; 87 #if IS_ENABLED(CONFIG_IPV6) 88 struct netns_ipv6 ipv6; 89 #endif 90 #if defined(CONFIG_IP_SCTP) || defined(CONFIG_IP_SCTP_MODULE) 91 struct netns_sctp sctp; 92 #endif 93 #if defined(CONFIG_IP_DCCP) || defined(CONFIG_IP_DCCP_MODULE) 94 struct netns_dccp dccp; 95 #endif 96 #ifdef CONFIG_NETFILTER 97 struct netns_xt xt; 98 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) 99 struct netns_ct ct; 100 #endif 101 #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6) 102 struct netns_nf_frag nf_frag; 103 #endif 104 struct sock *nfnl; 105 struct sock *nfnl_stash; 106 #endif 107 #ifdef CONFIG_WEXT_CORE 108 struct sk_buff_head wext_nlevents; 109 #endif 110 struct net_generic __rcu *gen; 111 112 /* Note : following structs are cache line aligned */ 113 #ifdef CONFIG_XFRM 114 struct netns_xfrm xfrm; 115 #endif 116 struct netns_ipvs *ipvs; 117 struct sock *diag_nlsk; 118 atomic_t rt_genid; 119 }; 120 121 /* 122 * ifindex generation is per-net namespace, and loopback is 123 * always the 1st device in ns (see net_dev_init), thus any 124 * loopback device should get ifindex 1 125 */ 126 127 #define LOOPBACK_IFINDEX 1 128 129 #include <linux/seq_file_net.h> 130 131 /* Init's network namespace */ 132 extern struct net init_net; 133 134 #ifdef CONFIG_NET_NS 135 extern struct net *copy_net_ns(unsigned long flags, 136 struct user_namespace *user_ns, struct net *old_net); 137 138 #else /* CONFIG_NET_NS */ 139 #include <linux/sched.h> 140 #include <linux/nsproxy.h> 141 static inline struct net *copy_net_ns(unsigned long flags, 142 struct user_namespace *user_ns, struct net *old_net) 143 { 144 if (flags & CLONE_NEWNET) 145 return ERR_PTR(-EINVAL); 146 return old_net; 147 } 148 #endif /* CONFIG_NET_NS */ 149 150 151 extern struct list_head net_namespace_list; 152 153 extern struct net *get_net_ns_by_pid(pid_t pid); 154 extern struct net *get_net_ns_by_fd(int pid); 155 156 #ifdef CONFIG_NET_NS 157 extern void __put_net(struct net *net); 158 159 static inline struct net *get_net(struct net *net) 160 { 161 atomic_inc(&net->count); 162 return net; 163 } 164 165 static inline struct net *maybe_get_net(struct net *net) 166 { 167 /* Used when we know struct net exists but we 168 * aren't guaranteed a previous reference count 169 * exists. If the reference count is zero this 170 * function fails and returns NULL. 171 */ 172 if (!atomic_inc_not_zero(&net->count)) 173 net = NULL; 174 return net; 175 } 176 177 static inline void put_net(struct net *net) 178 { 179 if (atomic_dec_and_test(&net->count)) 180 __put_net(net); 181 } 182 183 static inline 184 int net_eq(const struct net *net1, const struct net *net2) 185 { 186 return net1 == net2; 187 } 188 189 extern void net_drop_ns(void *); 190 191 #else 192 193 static inline struct net *get_net(struct net *net) 194 { 195 return net; 196 } 197 198 static inline void put_net(struct net *net) 199 { 200 } 201 202 static inline struct net *maybe_get_net(struct net *net) 203 { 204 return net; 205 } 206 207 static inline 208 int net_eq(const struct net *net1, const struct net *net2) 209 { 210 return 1; 211 } 212 213 #define net_drop_ns NULL 214 #endif 215 216 217 #ifdef NETNS_REFCNT_DEBUG 218 static inline struct net *hold_net(struct net *net) 219 { 220 if (net) 221 atomic_inc(&net->use_count); 222 return net; 223 } 224 225 static inline void release_net(struct net *net) 226 { 227 if (net) 228 atomic_dec(&net->use_count); 229 } 230 #else 231 static inline struct net *hold_net(struct net *net) 232 { 233 return net; 234 } 235 236 static inline void release_net(struct net *net) 237 { 238 } 239 #endif 240 241 #ifdef CONFIG_NET_NS 242 243 static inline void write_pnet(struct net **pnet, struct net *net) 244 { 245 *pnet = net; 246 } 247 248 static inline struct net *read_pnet(struct net * const *pnet) 249 { 250 return *pnet; 251 } 252 253 #else 254 255 #define write_pnet(pnet, net) do { (void)(net);} while (0) 256 #define read_pnet(pnet) (&init_net) 257 258 #endif 259 260 #define for_each_net(VAR) \ 261 list_for_each_entry(VAR, &net_namespace_list, list) 262 263 #define for_each_net_rcu(VAR) \ 264 list_for_each_entry_rcu(VAR, &net_namespace_list, list) 265 266 #ifdef CONFIG_NET_NS 267 #define __net_init 268 #define __net_exit 269 #define __net_initdata 270 #define __net_initconst 271 #else 272 #define __net_init __init 273 #define __net_exit __exit_refok 274 #define __net_initdata __initdata 275 #define __net_initconst __initconst 276 #endif 277 278 struct pernet_operations { 279 struct list_head list; 280 int (*init)(struct net *net); 281 void (*exit)(struct net *net); 282 void (*exit_batch)(struct list_head *net_exit_list); 283 int *id; 284 size_t size; 285 }; 286 287 /* 288 * Use these carefully. If you implement a network device and it 289 * needs per network namespace operations use device pernet operations, 290 * otherwise use pernet subsys operations. 291 * 292 * Network interfaces need to be removed from a dying netns _before_ 293 * subsys notifiers can be called, as most of the network code cleanup 294 * (which is done from subsys notifiers) runs with the assumption that 295 * dev_remove_pack has been called so no new packets will arrive during 296 * and after the cleanup functions have been called. dev_remove_pack 297 * is not per namespace so instead the guarantee of no more packets 298 * arriving in a network namespace is provided by ensuring that all 299 * network devices and all sockets have left the network namespace 300 * before the cleanup methods are called. 301 * 302 * For the longest time the ipv4 icmp code was registered as a pernet 303 * device which caused kernel oops, and panics during network 304 * namespace cleanup. So please don't get this wrong. 305 */ 306 extern int register_pernet_subsys(struct pernet_operations *); 307 extern void unregister_pernet_subsys(struct pernet_operations *); 308 extern int register_pernet_device(struct pernet_operations *); 309 extern void unregister_pernet_device(struct pernet_operations *); 310 311 struct ctl_table; 312 struct ctl_table_header; 313 314 #ifdef CONFIG_SYSCTL 315 extern int net_sysctl_init(void); 316 extern struct ctl_table_header *register_net_sysctl(struct net *net, 317 const char *path, struct ctl_table *table); 318 extern void unregister_net_sysctl_table(struct ctl_table_header *header); 319 #else 320 static inline int net_sysctl_init(void) { return 0; } 321 static inline struct ctl_table_header *register_net_sysctl(struct net *net, 322 const char *path, struct ctl_table *table) 323 { 324 return NULL; 325 } 326 static inline void unregister_net_sysctl_table(struct ctl_table_header *header) 327 { 328 } 329 #endif 330 331 static inline int rt_genid(struct net *net) 332 { 333 return atomic_read(&net->rt_genid); 334 } 335 336 static inline void rt_genid_bump(struct net *net) 337 { 338 atomic_inc(&net->rt_genid); 339 } 340 341 #endif /* __NET_NET_NAMESPACE_H */ 342