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_NET_NS 166 void __put_net(struct net *net); 167 168 static inline struct net *get_net(struct net *net) 169 { 170 atomic_inc(&net->count); 171 return net; 172 } 173 174 static inline struct net *maybe_get_net(struct net *net) 175 { 176 /* Used when we know struct net exists but we 177 * aren't guaranteed a previous reference count 178 * exists. If the reference count is zero this 179 * function fails and returns NULL. 180 */ 181 if (!atomic_inc_not_zero(&net->count)) 182 net = NULL; 183 return net; 184 } 185 186 static inline void put_net(struct net *net) 187 { 188 if (atomic_dec_and_test(&net->count)) 189 __put_net(net); 190 } 191 192 static inline 193 int net_eq(const struct net *net1, const struct net *net2) 194 { 195 return net1 == net2; 196 } 197 198 void net_drop_ns(void *); 199 200 #else 201 202 static inline struct net *get_net(struct net *net) 203 { 204 return net; 205 } 206 207 static inline void put_net(struct net *net) 208 { 209 } 210 211 static inline struct net *maybe_get_net(struct net *net) 212 { 213 return net; 214 } 215 216 static inline 217 int net_eq(const struct net *net1, const struct net *net2) 218 { 219 return 1; 220 } 221 222 #define net_drop_ns NULL 223 #endif 224 225 226 #ifdef NETNS_REFCNT_DEBUG 227 static inline struct net *hold_net(struct net *net) 228 { 229 if (net) 230 atomic_inc(&net->use_count); 231 return net; 232 } 233 234 static inline void release_net(struct net *net) 235 { 236 if (net) 237 atomic_dec(&net->use_count); 238 } 239 #else 240 static inline struct net *hold_net(struct net *net) 241 { 242 return net; 243 } 244 245 static inline void release_net(struct net *net) 246 { 247 } 248 #endif 249 250 #ifdef CONFIG_NET_NS 251 252 static inline void write_pnet(struct net **pnet, struct net *net) 253 { 254 *pnet = net; 255 } 256 257 static inline struct net *read_pnet(struct net * const *pnet) 258 { 259 return *pnet; 260 } 261 262 #else 263 264 #define write_pnet(pnet, net) do { (void)(net);} while (0) 265 #define read_pnet(pnet) (&init_net) 266 267 #endif 268 269 #define for_each_net(VAR) \ 270 list_for_each_entry(VAR, &net_namespace_list, list) 271 272 #define for_each_net_rcu(VAR) \ 273 list_for_each_entry_rcu(VAR, &net_namespace_list, list) 274 275 #ifdef CONFIG_NET_NS 276 #define __net_init 277 #define __net_exit 278 #define __net_initdata 279 #define __net_initconst 280 #else 281 #define __net_init __init 282 #define __net_exit __exit_refok 283 #define __net_initdata __initdata 284 #define __net_initconst __initconst 285 #endif 286 287 struct pernet_operations { 288 struct list_head list; 289 int (*init)(struct net *net); 290 void (*exit)(struct net *net); 291 void (*exit_batch)(struct list_head *net_exit_list); 292 int *id; 293 size_t size; 294 }; 295 296 /* 297 * Use these carefully. If you implement a network device and it 298 * needs per network namespace operations use device pernet operations, 299 * otherwise use pernet subsys operations. 300 * 301 * Network interfaces need to be removed from a dying netns _before_ 302 * subsys notifiers can be called, as most of the network code cleanup 303 * (which is done from subsys notifiers) runs with the assumption that 304 * dev_remove_pack has been called so no new packets will arrive during 305 * and after the cleanup functions have been called. dev_remove_pack 306 * is not per namespace so instead the guarantee of no more packets 307 * arriving in a network namespace is provided by ensuring that all 308 * network devices and all sockets have left the network namespace 309 * before the cleanup methods are called. 310 * 311 * For the longest time the ipv4 icmp code was registered as a pernet 312 * device which caused kernel oops, and panics during network 313 * namespace cleanup. So please don't get this wrong. 314 */ 315 int register_pernet_subsys(struct pernet_operations *); 316 void unregister_pernet_subsys(struct pernet_operations *); 317 int register_pernet_device(struct pernet_operations *); 318 void unregister_pernet_device(struct pernet_operations *); 319 320 struct ctl_table; 321 struct ctl_table_header; 322 323 #ifdef CONFIG_SYSCTL 324 int net_sysctl_init(void); 325 struct ctl_table_header *register_net_sysctl(struct net *net, const char *path, 326 struct ctl_table *table); 327 void unregister_net_sysctl_table(struct ctl_table_header *header); 328 #else 329 static inline int net_sysctl_init(void) { return 0; } 330 static inline struct ctl_table_header *register_net_sysctl(struct net *net, 331 const char *path, struct ctl_table *table) 332 { 333 return NULL; 334 } 335 static inline void unregister_net_sysctl_table(struct ctl_table_header *header) 336 { 337 } 338 #endif 339 340 static inline int rt_genid_ipv4(struct net *net) 341 { 342 return atomic_read(&net->ipv4.rt_genid); 343 } 344 345 static inline void rt_genid_bump_ipv4(struct net *net) 346 { 347 atomic_inc(&net->ipv4.rt_genid); 348 } 349 350 #if IS_ENABLED(CONFIG_IPV6) 351 static inline int rt_genid_ipv6(struct net *net) 352 { 353 return atomic_read(&net->ipv6.rt_genid); 354 } 355 356 static inline void rt_genid_bump_ipv6(struct net *net) 357 { 358 atomic_inc(&net->ipv6.rt_genid); 359 } 360 #else 361 static inline int rt_genid_ipv6(struct net *net) 362 { 363 return 0; 364 } 365 366 static inline void rt_genid_bump_ipv6(struct net *net) 367 { 368 } 369 #endif 370 371 /* For callers who don't really care about whether it's IPv4 or IPv6 */ 372 static inline void rt_genid_bump_all(struct net *net) 373 { 374 rt_genid_bump_ipv4(net); 375 rt_genid_bump_ipv6(net); 376 } 377 378 static inline int fnhe_genid(struct net *net) 379 { 380 return atomic_read(&net->fnhe_genid); 381 } 382 383 static inline void fnhe_genid_bump(struct net *net) 384 { 385 atomic_inc(&net->fnhe_genid); 386 } 387 388 #endif /* __NET_NET_NAMESPACE_H */ 389