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/netfilter.h> 21 #include <net/netns/x_tables.h> 22 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) 23 #include <net/netns/conntrack.h> 24 #endif 25 #include <net/netns/nftables.h> 26 #include <net/netns/xfrm.h> 27 28 struct user_namespace; 29 struct proc_dir_entry; 30 struct net_device; 31 struct sock; 32 struct ctl_table_header; 33 struct net_generic; 34 struct sock; 35 struct netns_ipvs; 36 37 38 #define NETDEV_HASHBITS 8 39 #define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS) 40 41 struct net { 42 atomic_t passive; /* To decided when the network 43 * namespace should be freed. 44 */ 45 atomic_t count; /* To decided when the network 46 * namespace should be shut down. 47 */ 48 #ifdef NETNS_REFCNT_DEBUG 49 atomic_t use_count; /* To track references we 50 * destroy on demand 51 */ 52 #endif 53 spinlock_t rules_mod_lock; 54 55 struct list_head list; /* list of network namespaces */ 56 struct list_head cleanup_list; /* namespaces on death row */ 57 struct list_head exit_list; /* Use only net_mutex */ 58 59 struct user_namespace *user_ns; /* Owning user namespace */ 60 61 unsigned int proc_inum; 62 63 struct proc_dir_entry *proc_net; 64 struct proc_dir_entry *proc_net_stat; 65 66 #ifdef CONFIG_SYSCTL 67 struct ctl_table_set sysctls; 68 #endif 69 70 struct sock *rtnl; /* rtnetlink socket */ 71 struct sock *genl_sock; 72 73 struct list_head dev_base_head; 74 struct hlist_head *dev_name_head; 75 struct hlist_head *dev_index_head; 76 unsigned int dev_base_seq; /* protected by rtnl_mutex */ 77 int ifindex; 78 unsigned int dev_unreg_count; 79 80 /* core fib_rules */ 81 struct list_head rules_ops; 82 83 84 struct net_device *loopback_dev; /* The loopback */ 85 struct netns_core core; 86 struct netns_mib mib; 87 struct netns_packet packet; 88 struct netns_unix unx; 89 struct netns_ipv4 ipv4; 90 #if IS_ENABLED(CONFIG_IPV6) 91 struct netns_ipv6 ipv6; 92 #endif 93 #if defined(CONFIG_IP_SCTP) || defined(CONFIG_IP_SCTP_MODULE) 94 struct netns_sctp sctp; 95 #endif 96 #if defined(CONFIG_IP_DCCP) || defined(CONFIG_IP_DCCP_MODULE) 97 struct netns_dccp dccp; 98 #endif 99 #ifdef CONFIG_NETFILTER 100 struct netns_nf nf; 101 struct netns_xt xt; 102 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) 103 struct netns_ct ct; 104 #endif 105 #if defined(CONFIG_NF_TABLES) || defined(CONFIG_NF_TABLES_MODULE) 106 struct netns_nftables nft; 107 #endif 108 #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6) 109 struct netns_nf_frag nf_frag; 110 #endif 111 struct sock *nfnl; 112 struct sock *nfnl_stash; 113 #endif 114 #ifdef CONFIG_WEXT_CORE 115 struct sk_buff_head wext_nlevents; 116 #endif 117 struct net_generic __rcu *gen; 118 119 /* Note : following structs are cache line aligned */ 120 #ifdef CONFIG_XFRM 121 struct netns_xfrm xfrm; 122 #endif 123 #if IS_ENABLED(CONFIG_IP_VS) 124 struct netns_ipvs *ipvs; 125 #endif 126 struct sock *diag_nlsk; 127 atomic_t fnhe_genid; 128 }; 129 130 /* 131 * ifindex generation is per-net namespace, and loopback is 132 * always the 1st device in ns (see net_dev_init), thus any 133 * loopback device should get ifindex 1 134 */ 135 136 #define LOOPBACK_IFINDEX 1 137 138 #include <linux/seq_file_net.h> 139 140 /* Init's network namespace */ 141 extern struct net init_net; 142 143 #ifdef CONFIG_NET_NS 144 struct net *copy_net_ns(unsigned long flags, struct user_namespace *user_ns, 145 struct net *old_net); 146 147 #else /* CONFIG_NET_NS */ 148 #include <linux/sched.h> 149 #include <linux/nsproxy.h> 150 static inline struct net *copy_net_ns(unsigned long flags, 151 struct user_namespace *user_ns, struct net *old_net) 152 { 153 if (flags & CLONE_NEWNET) 154 return ERR_PTR(-EINVAL); 155 return old_net; 156 } 157 #endif /* CONFIG_NET_NS */ 158 159 160 extern struct list_head net_namespace_list; 161 162 struct net *get_net_ns_by_pid(pid_t pid); 163 struct net *get_net_ns_by_fd(int pid); 164 165 #ifdef CONFIG_SYSCTL 166 void ipx_register_sysctl(void); 167 void ipx_unregister_sysctl(void); 168 #else 169 #define ipx_register_sysctl() 170 #define ipx_unregister_sysctl() 171 #endif 172 173 #ifdef CONFIG_NET_NS 174 void __put_net(struct net *net); 175 176 static inline struct net *get_net(struct net *net) 177 { 178 atomic_inc(&net->count); 179 return net; 180 } 181 182 static inline struct net *maybe_get_net(struct net *net) 183 { 184 /* Used when we know struct net exists but we 185 * aren't guaranteed a previous reference count 186 * exists. If the reference count is zero this 187 * function fails and returns NULL. 188 */ 189 if (!atomic_inc_not_zero(&net->count)) 190 net = NULL; 191 return net; 192 } 193 194 static inline void put_net(struct net *net) 195 { 196 if (atomic_dec_and_test(&net->count)) 197 __put_net(net); 198 } 199 200 static inline 201 int net_eq(const struct net *net1, const struct net *net2) 202 { 203 return net1 == net2; 204 } 205 206 void net_drop_ns(void *); 207 208 #else 209 210 static inline struct net *get_net(struct net *net) 211 { 212 return net; 213 } 214 215 static inline void put_net(struct net *net) 216 { 217 } 218 219 static inline struct net *maybe_get_net(struct net *net) 220 { 221 return net; 222 } 223 224 static inline 225 int net_eq(const struct net *net1, const struct net *net2) 226 { 227 return 1; 228 } 229 230 #define net_drop_ns NULL 231 #endif 232 233 234 #ifdef NETNS_REFCNT_DEBUG 235 static inline struct net *hold_net(struct net *net) 236 { 237 if (net) 238 atomic_inc(&net->use_count); 239 return net; 240 } 241 242 static inline void release_net(struct net *net) 243 { 244 if (net) 245 atomic_dec(&net->use_count); 246 } 247 #else 248 static inline struct net *hold_net(struct net *net) 249 { 250 return net; 251 } 252 253 static inline void release_net(struct net *net) 254 { 255 } 256 #endif 257 258 #ifdef CONFIG_NET_NS 259 260 static inline void write_pnet(struct net **pnet, struct net *net) 261 { 262 *pnet = net; 263 } 264 265 static inline struct net *read_pnet(struct net * const *pnet) 266 { 267 return *pnet; 268 } 269 270 #else 271 272 #define write_pnet(pnet, net) do { (void)(net);} while (0) 273 #define read_pnet(pnet) (&init_net) 274 275 #endif 276 277 #define for_each_net(VAR) \ 278 list_for_each_entry(VAR, &net_namespace_list, list) 279 280 #define for_each_net_rcu(VAR) \ 281 list_for_each_entry_rcu(VAR, &net_namespace_list, list) 282 283 #ifdef CONFIG_NET_NS 284 #define __net_init 285 #define __net_exit 286 #define __net_initdata 287 #define __net_initconst 288 #else 289 #define __net_init __init 290 #define __net_exit __exit_refok 291 #define __net_initdata __initdata 292 #define __net_initconst __initconst 293 #endif 294 295 struct pernet_operations { 296 struct list_head list; 297 int (*init)(struct net *net); 298 void (*exit)(struct net *net); 299 void (*exit_batch)(struct list_head *net_exit_list); 300 int *id; 301 size_t size; 302 }; 303 304 /* 305 * Use these carefully. If you implement a network device and it 306 * needs per network namespace operations use device pernet operations, 307 * otherwise use pernet subsys operations. 308 * 309 * Network interfaces need to be removed from a dying netns _before_ 310 * subsys notifiers can be called, as most of the network code cleanup 311 * (which is done from subsys notifiers) runs with the assumption that 312 * dev_remove_pack has been called so no new packets will arrive during 313 * and after the cleanup functions have been called. dev_remove_pack 314 * is not per namespace so instead the guarantee of no more packets 315 * arriving in a network namespace is provided by ensuring that all 316 * network devices and all sockets have left the network namespace 317 * before the cleanup methods are called. 318 * 319 * For the longest time the ipv4 icmp code was registered as a pernet 320 * device which caused kernel oops, and panics during network 321 * namespace cleanup. So please don't get this wrong. 322 */ 323 int register_pernet_subsys(struct pernet_operations *); 324 void unregister_pernet_subsys(struct pernet_operations *); 325 int register_pernet_device(struct pernet_operations *); 326 void unregister_pernet_device(struct pernet_operations *); 327 328 struct ctl_table; 329 struct ctl_table_header; 330 331 #ifdef CONFIG_SYSCTL 332 int net_sysctl_init(void); 333 struct ctl_table_header *register_net_sysctl(struct net *net, const char *path, 334 struct ctl_table *table); 335 void unregister_net_sysctl_table(struct ctl_table_header *header); 336 #else 337 static inline int net_sysctl_init(void) { return 0; } 338 static inline struct ctl_table_header *register_net_sysctl(struct net *net, 339 const char *path, struct ctl_table *table) 340 { 341 return NULL; 342 } 343 static inline void unregister_net_sysctl_table(struct ctl_table_header *header) 344 { 345 } 346 #endif 347 348 static inline int rt_genid_ipv4(struct net *net) 349 { 350 return atomic_read(&net->ipv4.rt_genid); 351 } 352 353 static inline void rt_genid_bump_ipv4(struct net *net) 354 { 355 atomic_inc(&net->ipv4.rt_genid); 356 } 357 358 #if IS_ENABLED(CONFIG_IPV6) 359 static inline int rt_genid_ipv6(struct net *net) 360 { 361 return atomic_read(&net->ipv6.rt_genid); 362 } 363 364 static inline void rt_genid_bump_ipv6(struct net *net) 365 { 366 atomic_inc(&net->ipv6.rt_genid); 367 } 368 #else 369 static inline int rt_genid_ipv6(struct net *net) 370 { 371 return 0; 372 } 373 374 static inline void rt_genid_bump_ipv6(struct net *net) 375 { 376 } 377 #endif 378 379 /* For callers who don't really care about whether it's IPv4 or IPv6 */ 380 static inline void rt_genid_bump_all(struct net *net) 381 { 382 rt_genid_bump_ipv4(net); 383 rt_genid_bump_ipv6(net); 384 } 385 386 static inline int fnhe_genid(struct net *net) 387 { 388 return atomic_read(&net->fnhe_genid); 389 } 390 391 static inline void fnhe_genid_bump(struct net *net) 392 { 393 atomic_inc(&net->fnhe_genid); 394 } 395 396 #endif /* __NET_NET_NAMESPACE_H */ 397