1 /* SPDX-License-Identifier: GPL-2.0 */
3 * Operations on the network namespace
5 #ifndef __NET_NET_NAMESPACE_H
6 #define __NET_NET_NAMESPACE_H
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 #include <linux/uidgid.h>
16 #include <net/netns/core.h>
17 #include <net/netns/mib.h>
18 #include <net/netns/unix.h>
19 #include <net/netns/packet.h>
20 #include <net/netns/ipv4.h>
21 #include <net/netns/ipv6.h>
22 #include <net/netns/nexthop.h>
23 #include <net/netns/ieee802154_6lowpan.h>
24 #include <net/netns/sctp.h>
25 #include <net/netns/netfilter.h>
26 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
27 #include <net/netns/conntrack.h>
29 #if IS_ENABLED(CONFIG_NF_FLOW_TABLE)
30 #include <net/netns/flow_table.h>
32 #include <net/netns/nftables.h>
33 #include <net/netns/xfrm.h>
34 #include <net/netns/mpls.h>
35 #include <net/netns/can.h>
36 #include <net/netns/xdp.h>
37 #include <net/netns/smc.h>
38 #include <net/netns/bpf.h>
39 #include <net/netns/mctp.h>
40 #include <net/net_trackers.h>
41 #include <linux/ns_common.h>
42 #include <linux/idr.h>
43 #include <linux/skbuff.h>
44 #include <linux/notifier.h>
45 #include <linux/xarray.h>
47 struct user_namespace;
48 struct proc_dir_entry;
51 struct ctl_table_header;
58 #define NETDEV_HASHBITS 8
59 #define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS)
62 /* First cache line can be often dirtied.
63 * Do not place here read-mostly fields.
65 refcount_t passive; /* To decide when the network
66 * namespace should be freed.
68 spinlock_t rules_mod_lock;
70 unsigned int dev_base_seq; /* protected by rtnl_mutex */
76 struct list_head list; /* list of network namespaces */
77 struct list_head exit_list; /* To linked to call pernet exit
78 * methods on dead net (
79 * pernet_ops_rwsem read locked),
80 * or to unregister pernet ops
81 * (pernet_ops_rwsem write locked).
83 struct llist_node cleanup_list; /* namespaces on death row */
86 struct key_tag *key_domain; /* Key domain of operation tag */
88 struct user_namespace *user_ns; /* Owning user namespace */
89 struct ucounts *ucounts;
93 struct ref_tracker_dir refcnt_tracker;
94 struct ref_tracker_dir notrefcnt_tracker; /* tracker for objects not
95 * refcounted against netns
97 struct list_head dev_base_head;
98 struct proc_dir_entry *proc_net;
99 struct proc_dir_entry *proc_net_stat;
102 struct ctl_table_set sysctls;
105 struct sock *rtnl; /* rtnetlink socket */
106 struct sock *genl_sock;
108 struct uevent_sock *uevent_sock; /* uevent socket */
110 struct hlist_head *dev_name_head;
111 struct hlist_head *dev_index_head;
112 struct xarray dev_by_index;
113 struct raw_notifier_head netdev_chain;
115 /* Note that @hash_mix can be read millions times per second,
116 * it is critical that it is on a read_mostly cache line.
120 struct net_device *loopback_dev; /* The loopback */
123 struct list_head rules_ops;
125 struct netns_core core;
126 struct netns_mib mib;
127 struct netns_packet packet;
128 #if IS_ENABLED(CONFIG_UNIX)
129 struct netns_unix unx;
131 struct netns_nexthop nexthop;
132 struct netns_ipv4 ipv4;
133 #if IS_ENABLED(CONFIG_IPV6)
134 struct netns_ipv6 ipv6;
136 #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
137 struct netns_ieee802154_lowpan ieee802154_lowpan;
139 #if defined(CONFIG_IP_SCTP) || defined(CONFIG_IP_SCTP_MODULE)
140 struct netns_sctp sctp;
142 #ifdef CONFIG_NETFILTER
144 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
147 #if defined(CONFIG_NF_TABLES) || defined(CONFIG_NF_TABLES_MODULE)
148 struct netns_nftables nft;
150 #if IS_ENABLED(CONFIG_NF_FLOW_TABLE)
154 #ifdef CONFIG_WEXT_CORE
155 struct sk_buff_head wext_nlevents;
157 struct net_generic __rcu *gen;
159 /* Used to store attached BPF programs */
160 struct netns_bpf bpf;
162 /* Note : following structs are cache line aligned */
164 struct netns_xfrm xfrm;
167 u64 net_cookie; /* written once */
169 #if IS_ENABLED(CONFIG_IP_VS)
170 struct netns_ipvs *ipvs;
172 #if IS_ENABLED(CONFIG_MPLS)
173 struct netns_mpls mpls;
175 #if IS_ENABLED(CONFIG_CAN)
176 struct netns_can can;
178 #ifdef CONFIG_XDP_SOCKETS
179 struct netns_xdp xdp;
181 #if IS_ENABLED(CONFIG_MCTP)
182 struct netns_mctp mctp;
184 #if IS_ENABLED(CONFIG_CRYPTO_USER)
185 struct sock *crypto_nlsk;
187 struct sock *diag_nlsk;
188 #if IS_ENABLED(CONFIG_SMC)
189 struct netns_smc smc;
191 } __randomize_layout;
193 #include <linux/seq_file_net.h>
195 /* Init's network namespace */
196 extern struct net init_net;
199 struct net *copy_net_ns(unsigned long flags, struct user_namespace *user_ns,
200 struct net *old_net);
202 void net_ns_get_ownership(const struct net *net, kuid_t *uid, kgid_t *gid);
204 void net_ns_barrier(void);
206 struct ns_common *get_net_ns(struct ns_common *ns);
207 struct net *get_net_ns_by_fd(int fd);
208 #else /* CONFIG_NET_NS */
209 #include <linux/sched.h>
210 #include <linux/nsproxy.h>
211 static inline struct net *copy_net_ns(unsigned long flags,
212 struct user_namespace *user_ns, struct net *old_net)
214 if (flags & CLONE_NEWNET)
215 return ERR_PTR(-EINVAL);
219 static inline void net_ns_get_ownership(const struct net *net,
220 kuid_t *uid, kgid_t *gid)
222 *uid = GLOBAL_ROOT_UID;
223 *gid = GLOBAL_ROOT_GID;
226 static inline void net_ns_barrier(void) {}
228 static inline struct ns_common *get_net_ns(struct ns_common *ns)
230 return ERR_PTR(-EINVAL);
233 static inline struct net *get_net_ns_by_fd(int fd)
235 return ERR_PTR(-EINVAL);
237 #endif /* CONFIG_NET_NS */
240 extern struct list_head net_namespace_list;
242 struct net *get_net_ns_by_pid(pid_t pid);
245 void ipx_register_sysctl(void);
246 void ipx_unregister_sysctl(void);
248 #define ipx_register_sysctl()
249 #define ipx_unregister_sysctl()
253 void __put_net(struct net *net);
255 /* Try using get_net_track() instead */
256 static inline struct net *get_net(struct net *net)
258 refcount_inc(&net->ns.count);
262 static inline struct net *maybe_get_net(struct net *net)
264 /* Used when we know struct net exists but we
265 * aren't guaranteed a previous reference count
266 * exists. If the reference count is zero this
267 * function fails and returns NULL.
269 if (!refcount_inc_not_zero(&net->ns.count))
274 /* Try using put_net_track() instead */
275 static inline void put_net(struct net *net)
277 if (refcount_dec_and_test(&net->ns.count))
282 int net_eq(const struct net *net1, const struct net *net2)
287 static inline int check_net(const struct net *net)
289 return refcount_read(&net->ns.count) != 0;
292 void net_drop_ns(void *);
296 static inline struct net *get_net(struct net *net)
301 static inline void put_net(struct net *net)
305 static inline struct net *maybe_get_net(struct net *net)
311 int net_eq(const struct net *net1, const struct net *net2)
316 static inline int check_net(const struct net *net)
321 #define net_drop_ns NULL
325 static inline void __netns_tracker_alloc(struct net *net,
326 netns_tracker *tracker,
330 #ifdef CONFIG_NET_NS_REFCNT_TRACKER
331 ref_tracker_alloc(refcounted ? &net->refcnt_tracker :
332 &net->notrefcnt_tracker,
337 static inline void netns_tracker_alloc(struct net *net, netns_tracker *tracker,
340 __netns_tracker_alloc(net, tracker, true, gfp);
343 static inline void __netns_tracker_free(struct net *net,
344 netns_tracker *tracker,
347 #ifdef CONFIG_NET_NS_REFCNT_TRACKER
348 ref_tracker_free(refcounted ? &net->refcnt_tracker :
349 &net->notrefcnt_tracker, tracker);
353 static inline struct net *get_net_track(struct net *net,
354 netns_tracker *tracker, gfp_t gfp)
357 netns_tracker_alloc(net, tracker, gfp);
361 static inline void put_net_track(struct net *net, netns_tracker *tracker)
363 __netns_tracker_free(net, tracker, true);
369 struct net __rcu *net;
373 static inline void write_pnet(possible_net_t *pnet, struct net *net)
376 rcu_assign_pointer(pnet->net, net);
380 static inline struct net *read_pnet(const possible_net_t *pnet)
383 return rcu_dereference_protected(pnet->net, true);
389 static inline struct net *read_pnet_rcu(possible_net_t *pnet)
392 return rcu_dereference(pnet->net);
398 /* Protected by net_rwsem */
399 #define for_each_net(VAR) \
400 list_for_each_entry(VAR, &net_namespace_list, list)
401 #define for_each_net_continue_reverse(VAR) \
402 list_for_each_entry_continue_reverse(VAR, &net_namespace_list, list)
403 #define for_each_net_rcu(VAR) \
404 list_for_each_entry_rcu(VAR, &net_namespace_list, list)
409 #define __net_initdata
410 #define __net_initconst
412 #define __net_init __init
413 #define __net_exit __ref
414 #define __net_initdata __initdata
415 #define __net_initconst __initconst
418 int peernet2id_alloc(struct net *net, struct net *peer, gfp_t gfp);
419 int peernet2id(const struct net *net, struct net *peer);
420 bool peernet_has_id(const struct net *net, struct net *peer);
421 struct net *get_net_ns_by_id(const struct net *net, int id);
423 struct pernet_operations {
424 struct list_head list;
426 * Below methods are called without any exclusive locks.
427 * More than one net may be constructed and destructed
428 * in parallel on several cpus. Every pernet_operations
429 * have to keep in mind all other pernet_operations and
430 * to introduce a locking, if they share common resources.
432 * The only time they are called with exclusive lock is
433 * from register_pernet_subsys(), unregister_pernet_subsys()
434 * register_pernet_device() and unregister_pernet_device().
436 * Exit methods using blocking RCU primitives, such as
437 * synchronize_rcu(), should be implemented via exit_batch.
438 * Then, destruction of a group of net requires single
439 * synchronize_rcu() related to these pernet_operations,
440 * instead of separate synchronize_rcu() for every net.
441 * Please, avoid synchronize_rcu() at all, where it's possible.
443 * Note that a combination of pre_exit() and exit() can
444 * be used, since a synchronize_rcu() is guaranteed between
447 int (*init)(struct net *net);
448 void (*pre_exit)(struct net *net);
449 void (*exit)(struct net *net);
450 void (*exit_batch)(struct list_head *net_exit_list);
451 /* Following method is called with RTNL held. */
452 void (*exit_batch_rtnl)(struct list_head *net_exit_list,
453 struct list_head *dev_kill_list);
459 * Use these carefully. If you implement a network device and it
460 * needs per network namespace operations use device pernet operations,
461 * otherwise use pernet subsys operations.
463 * Network interfaces need to be removed from a dying netns _before_
464 * subsys notifiers can be called, as most of the network code cleanup
465 * (which is done from subsys notifiers) runs with the assumption that
466 * dev_remove_pack has been called so no new packets will arrive during
467 * and after the cleanup functions have been called. dev_remove_pack
468 * is not per namespace so instead the guarantee of no more packets
469 * arriving in a network namespace is provided by ensuring that all
470 * network devices and all sockets have left the network namespace
471 * before the cleanup methods are called.
473 * For the longest time the ipv4 icmp code was registered as a pernet
474 * device which caused kernel oops, and panics during network
475 * namespace cleanup. So please don't get this wrong.
477 int register_pernet_subsys(struct pernet_operations *);
478 void unregister_pernet_subsys(struct pernet_operations *);
479 int register_pernet_device(struct pernet_operations *);
480 void unregister_pernet_device(struct pernet_operations *);
484 #define register_net_sysctl(net, path, table) \
485 register_net_sysctl_sz(net, path, table, ARRAY_SIZE(table))
487 int net_sysctl_init(void);
488 struct ctl_table_header *register_net_sysctl_sz(struct net *net, const char *path,
489 struct ctl_table *table, size_t table_size);
490 void unregister_net_sysctl_table(struct ctl_table_header *header);
492 static inline int net_sysctl_init(void) { return 0; }
493 static inline struct ctl_table_header *register_net_sysctl_sz(struct net *net,
494 const char *path, struct ctl_table *table, size_t table_size)
498 static inline void unregister_net_sysctl_table(struct ctl_table_header *header)
503 static inline int rt_genid_ipv4(const struct net *net)
505 return atomic_read(&net->ipv4.rt_genid);
508 #if IS_ENABLED(CONFIG_IPV6)
509 static inline int rt_genid_ipv6(const struct net *net)
511 return atomic_read(&net->ipv6.fib6_sernum);
515 static inline void rt_genid_bump_ipv4(struct net *net)
517 atomic_inc(&net->ipv4.rt_genid);
520 extern void (*__fib6_flush_trees)(struct net *net);
521 static inline void rt_genid_bump_ipv6(struct net *net)
523 if (__fib6_flush_trees)
524 __fib6_flush_trees(net);
527 #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
528 static inline struct netns_ieee802154_lowpan *
529 net_ieee802154_lowpan(struct net *net)
531 return &net->ieee802154_lowpan;
535 /* For callers who don't really care about whether it's IPv4 or IPv6 */
536 static inline void rt_genid_bump_all(struct net *net)
538 rt_genid_bump_ipv4(net);
539 rt_genid_bump_ipv6(net);
542 static inline int fnhe_genid(const struct net *net)
544 return atomic_read(&net->fnhe_genid);
547 static inline void fnhe_genid_bump(struct net *net)
549 atomic_inc(&net->fnhe_genid);
553 void net_ns_init(void);
555 static inline void net_ns_init(void) {}
558 #endif /* __NET_NET_NAMESPACE_H */