1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Operations on the network namespace 4 */ 5 #ifndef __NET_NET_NAMESPACE_H 6 #define __NET_NET_NAMESPACE_H 7 8 #include <linux/atomic.h> 9 #include <linux/refcount.h> 10 #include <linux/workqueue.h> 11 #include <linux/list.h> 12 #include <linux/sysctl.h> 13 14 #include <net/flow.h> 15 #include <net/netns/core.h> 16 #include <net/netns/mib.h> 17 #include <net/netns/unix.h> 18 #include <net/netns/packet.h> 19 #include <net/netns/ipv4.h> 20 #include <net/netns/ipv6.h> 21 #include <net/netns/ieee802154_6lowpan.h> 22 #include <net/netns/sctp.h> 23 #include <net/netns/dccp.h> 24 #include <net/netns/netfilter.h> 25 #include <net/netns/x_tables.h> 26 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) 27 #include <net/netns/conntrack.h> 28 #endif 29 #include <net/netns/nftables.h> 30 #include <net/netns/xfrm.h> 31 #include <net/netns/mpls.h> 32 #include <net/netns/can.h> 33 #include <linux/ns_common.h> 34 #include <linux/idr.h> 35 #include <linux/skbuff.h> 36 37 struct user_namespace; 38 struct proc_dir_entry; 39 struct net_device; 40 struct sock; 41 struct ctl_table_header; 42 struct net_generic; 43 struct sock; 44 struct netns_ipvs; 45 46 47 #define NETDEV_HASHBITS 8 48 #define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS) 49 50 struct net { 51 refcount_t passive; /* To decided when the network 52 * namespace should be freed. 53 */ 54 refcount_t count; /* To decided when the network 55 * namespace should be shut down. 56 */ 57 spinlock_t rules_mod_lock; 58 59 atomic64_t cookie_gen; 60 61 struct list_head list; /* list of network namespaces */ 62 struct list_head cleanup_list; /* namespaces on death row */ 63 struct list_head exit_list; /* Use only net_mutex */ 64 65 struct user_namespace *user_ns; /* Owning user namespace */ 66 struct ucounts *ucounts; 67 spinlock_t nsid_lock; 68 struct idr netns_ids; 69 70 struct ns_common ns; 71 72 struct proc_dir_entry *proc_net; 73 struct proc_dir_entry *proc_net_stat; 74 75 #ifdef CONFIG_SYSCTL 76 struct ctl_table_set sysctls; 77 #endif 78 79 struct sock *rtnl; /* rtnetlink socket */ 80 struct sock *genl_sock; 81 82 struct list_head dev_base_head; 83 struct hlist_head *dev_name_head; 84 struct hlist_head *dev_index_head; 85 unsigned int dev_base_seq; /* protected by rtnl_mutex */ 86 int ifindex; 87 unsigned int dev_unreg_count; 88 89 /* core fib_rules */ 90 struct list_head rules_ops; 91 92 struct list_head fib_notifier_ops; /* protected by net_mutex */ 93 94 struct net_device *loopback_dev; /* The loopback */ 95 struct netns_core core; 96 struct netns_mib mib; 97 struct netns_packet packet; 98 struct netns_unix unx; 99 struct netns_ipv4 ipv4; 100 #if IS_ENABLED(CONFIG_IPV6) 101 struct netns_ipv6 ipv6; 102 #endif 103 #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN) 104 struct netns_ieee802154_lowpan ieee802154_lowpan; 105 #endif 106 #if defined(CONFIG_IP_SCTP) || defined(CONFIG_IP_SCTP_MODULE) 107 struct netns_sctp sctp; 108 #endif 109 #if defined(CONFIG_IP_DCCP) || defined(CONFIG_IP_DCCP_MODULE) 110 struct netns_dccp dccp; 111 #endif 112 #ifdef CONFIG_NETFILTER 113 struct netns_nf nf; 114 struct netns_xt xt; 115 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) 116 struct netns_ct ct; 117 #endif 118 #if defined(CONFIG_NF_TABLES) || defined(CONFIG_NF_TABLES_MODULE) 119 struct netns_nftables nft; 120 #endif 121 #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6) 122 struct netns_nf_frag nf_frag; 123 #endif 124 struct sock *nfnl; 125 struct sock *nfnl_stash; 126 #if IS_ENABLED(CONFIG_NETFILTER_NETLINK_ACCT) 127 struct list_head nfnl_acct_list; 128 #endif 129 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT) 130 struct list_head nfct_timeout_list; 131 #endif 132 #endif 133 #ifdef CONFIG_WEXT_CORE 134 struct sk_buff_head wext_nlevents; 135 #endif 136 struct net_generic __rcu *gen; 137 138 /* Note : following structs are cache line aligned */ 139 #ifdef CONFIG_XFRM 140 struct netns_xfrm xfrm; 141 #endif 142 #if IS_ENABLED(CONFIG_IP_VS) 143 struct netns_ipvs *ipvs; 144 #endif 145 #if IS_ENABLED(CONFIG_MPLS) 146 struct netns_mpls mpls; 147 #endif 148 #if IS_ENABLED(CONFIG_CAN) 149 struct netns_can can; 150 #endif 151 struct sock *diag_nlsk; 152 atomic_t fnhe_genid; 153 } __randomize_layout; 154 155 #include <linux/seq_file_net.h> 156 157 /* Init's network namespace */ 158 extern struct net init_net; 159 160 #ifdef CONFIG_NET_NS 161 struct net *copy_net_ns(unsigned long flags, struct user_namespace *user_ns, 162 struct net *old_net); 163 164 void net_ns_barrier(void); 165 #else /* CONFIG_NET_NS */ 166 #include <linux/sched.h> 167 #include <linux/nsproxy.h> 168 static inline struct net *copy_net_ns(unsigned long flags, 169 struct user_namespace *user_ns, struct net *old_net) 170 { 171 if (flags & CLONE_NEWNET) 172 return ERR_PTR(-EINVAL); 173 return old_net; 174 } 175 176 static inline void net_ns_barrier(void) {} 177 #endif /* CONFIG_NET_NS */ 178 179 180 extern struct list_head net_namespace_list; 181 182 struct net *get_net_ns_by_pid(pid_t pid); 183 struct net *get_net_ns_by_fd(int fd); 184 185 #ifdef CONFIG_SYSCTL 186 void ipx_register_sysctl(void); 187 void ipx_unregister_sysctl(void); 188 #else 189 #define ipx_register_sysctl() 190 #define ipx_unregister_sysctl() 191 #endif 192 193 #ifdef CONFIG_NET_NS 194 void __put_net(struct net *net); 195 196 static inline struct net *get_net(struct net *net) 197 { 198 refcount_inc(&net->count); 199 return net; 200 } 201 202 static inline struct net *maybe_get_net(struct net *net) 203 { 204 /* Used when we know struct net exists but we 205 * aren't guaranteed a previous reference count 206 * exists. If the reference count is zero this 207 * function fails and returns NULL. 208 */ 209 if (!refcount_inc_not_zero(&net->count)) 210 net = NULL; 211 return net; 212 } 213 214 static inline void put_net(struct net *net) 215 { 216 if (refcount_dec_and_test(&net->count)) 217 __put_net(net); 218 } 219 220 static inline 221 int net_eq(const struct net *net1, const struct net *net2) 222 { 223 return net1 == net2; 224 } 225 226 static inline int check_net(const struct net *net) 227 { 228 return refcount_read(&net->count) != 0; 229 } 230 231 void net_drop_ns(void *); 232 233 #else 234 235 static inline struct net *get_net(struct net *net) 236 { 237 return net; 238 } 239 240 static inline void put_net(struct net *net) 241 { 242 } 243 244 static inline struct net *maybe_get_net(struct net *net) 245 { 246 return net; 247 } 248 249 static inline 250 int net_eq(const struct net *net1, const struct net *net2) 251 { 252 return 1; 253 } 254 255 static inline int check_net(const struct net *net) 256 { 257 return 1; 258 } 259 260 #define net_drop_ns NULL 261 #endif 262 263 264 typedef struct { 265 #ifdef CONFIG_NET_NS 266 struct net *net; 267 #endif 268 } possible_net_t; 269 270 static inline void write_pnet(possible_net_t *pnet, struct net *net) 271 { 272 #ifdef CONFIG_NET_NS 273 pnet->net = net; 274 #endif 275 } 276 277 static inline struct net *read_pnet(const possible_net_t *pnet) 278 { 279 #ifdef CONFIG_NET_NS 280 return pnet->net; 281 #else 282 return &init_net; 283 #endif 284 } 285 286 #define for_each_net(VAR) \ 287 list_for_each_entry(VAR, &net_namespace_list, list) 288 289 #define for_each_net_rcu(VAR) \ 290 list_for_each_entry_rcu(VAR, &net_namespace_list, list) 291 292 #ifdef CONFIG_NET_NS 293 #define __net_init 294 #define __net_exit 295 #define __net_initdata 296 #define __net_initconst 297 #else 298 #define __net_init __init 299 #define __net_exit __ref 300 #define __net_initdata __initdata 301 #define __net_initconst __initconst 302 #endif 303 304 int peernet2id_alloc(struct net *net, struct net *peer); 305 int peernet2id(struct net *net, struct net *peer); 306 bool peernet_has_id(struct net *net, struct net *peer); 307 struct net *get_net_ns_by_id(struct net *net, int id); 308 309 struct pernet_operations { 310 struct list_head list; 311 int (*init)(struct net *net); 312 void (*exit)(struct net *net); 313 void (*exit_batch)(struct list_head *net_exit_list); 314 unsigned int *id; 315 size_t size; 316 /* 317 * Indicates above methods are allowed to be executed in parallel 318 * with methods of any other pernet_operations, i.e. they are not 319 * need synchronization via net_mutex. 320 */ 321 bool async; 322 }; 323 324 /* 325 * Use these carefully. If you implement a network device and it 326 * needs per network namespace operations use device pernet operations, 327 * otherwise use pernet subsys operations. 328 * 329 * Network interfaces need to be removed from a dying netns _before_ 330 * subsys notifiers can be called, as most of the network code cleanup 331 * (which is done from subsys notifiers) runs with the assumption that 332 * dev_remove_pack has been called so no new packets will arrive during 333 * and after the cleanup functions have been called. dev_remove_pack 334 * is not per namespace so instead the guarantee of no more packets 335 * arriving in a network namespace is provided by ensuring that all 336 * network devices and all sockets have left the network namespace 337 * before the cleanup methods are called. 338 * 339 * For the longest time the ipv4 icmp code was registered as a pernet 340 * device which caused kernel oops, and panics during network 341 * namespace cleanup. So please don't get this wrong. 342 */ 343 int register_pernet_subsys(struct pernet_operations *); 344 void unregister_pernet_subsys(struct pernet_operations *); 345 int register_pernet_device(struct pernet_operations *); 346 void unregister_pernet_device(struct pernet_operations *); 347 348 struct ctl_table; 349 struct ctl_table_header; 350 351 #ifdef CONFIG_SYSCTL 352 int net_sysctl_init(void); 353 struct ctl_table_header *register_net_sysctl(struct net *net, const char *path, 354 struct ctl_table *table); 355 void unregister_net_sysctl_table(struct ctl_table_header *header); 356 #else 357 static inline int net_sysctl_init(void) { return 0; } 358 static inline struct ctl_table_header *register_net_sysctl(struct net *net, 359 const char *path, struct ctl_table *table) 360 { 361 return NULL; 362 } 363 static inline void unregister_net_sysctl_table(struct ctl_table_header *header) 364 { 365 } 366 #endif 367 368 static inline int rt_genid_ipv4(struct net *net) 369 { 370 return atomic_read(&net->ipv4.rt_genid); 371 } 372 373 static inline void rt_genid_bump_ipv4(struct net *net) 374 { 375 atomic_inc(&net->ipv4.rt_genid); 376 } 377 378 extern void (*__fib6_flush_trees)(struct net *net); 379 static inline void rt_genid_bump_ipv6(struct net *net) 380 { 381 if (__fib6_flush_trees) 382 __fib6_flush_trees(net); 383 } 384 385 #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN) 386 static inline struct netns_ieee802154_lowpan * 387 net_ieee802154_lowpan(struct net *net) 388 { 389 return &net->ieee802154_lowpan; 390 } 391 #endif 392 393 /* For callers who don't really care about whether it's IPv4 or IPv6 */ 394 static inline void rt_genid_bump_all(struct net *net) 395 { 396 rt_genid_bump_ipv4(net); 397 rt_genid_bump_ipv6(net); 398 } 399 400 static inline int fnhe_genid(struct net *net) 401 { 402 return atomic_read(&net->fnhe_genid); 403 } 404 405 static inline void fnhe_genid_bump(struct net *net) 406 { 407 atomic_inc(&net->fnhe_genid); 408 } 409 410 #endif /* __NET_NET_NAMESPACE_H */ 411