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