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