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 #include <net/netns/x_tables.h>
27 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
28 #include <net/netns/conntrack.h>
30 #include <net/netns/nftables.h>
31 #include <net/netns/xfrm.h>
32 #include <net/netns/mpls.h>
33 #include <net/netns/can.h>
34 #include <net/netns/xdp.h>
35 #include <net/netns/bpf.h>
36 #include <linux/ns_common.h>
37 #include <linux/idr.h>
38 #include <linux/skbuff.h>
39 #include <linux/notifier.h>
41 struct user_namespace;
42 struct proc_dir_entry;
45 struct ctl_table_header;
52 #define NETDEV_HASHBITS 8
53 #define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS)
56 /* First cache line can be often dirtied.
57 * Do not place here read-mostly fields.
59 refcount_t passive; /* To decide when the network
60 * namespace should be freed.
62 spinlock_t rules_mod_lock;
64 unsigned int dev_unreg_count;
66 unsigned int dev_base_seq; /* protected by rtnl_mutex */
72 struct list_head list; /* list of network namespaces */
73 struct list_head exit_list; /* To linked to call pernet exit
74 * methods on dead net (
75 * pernet_ops_rwsem read locked),
76 * or to unregister pernet ops
77 * (pernet_ops_rwsem write locked).
79 struct llist_node cleanup_list; /* namespaces on death row */
82 struct key_tag *key_domain; /* Key domain of operation tag */
84 struct user_namespace *user_ns; /* Owning user namespace */
85 struct ucounts *ucounts;
90 struct list_head dev_base_head;
91 struct proc_dir_entry *proc_net;
92 struct proc_dir_entry *proc_net_stat;
95 struct ctl_table_set sysctls;
98 struct sock *rtnl; /* rtnetlink socket */
99 struct sock *genl_sock;
101 struct uevent_sock *uevent_sock; /* uevent socket */
103 struct hlist_head *dev_name_head;
104 struct hlist_head *dev_index_head;
105 struct raw_notifier_head netdev_chain;
107 /* Note that @hash_mix can be read millions times per second,
108 * it is critical that it is on a read_mostly cache line.
112 struct net_device *loopback_dev; /* The loopback */
115 struct list_head rules_ops;
117 struct netns_core core;
118 struct netns_mib mib;
119 struct netns_packet packet;
120 struct netns_unix unx;
121 struct netns_nexthop nexthop;
122 struct netns_ipv4 ipv4;
123 #if IS_ENABLED(CONFIG_IPV6)
124 struct netns_ipv6 ipv6;
126 #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
127 struct netns_ieee802154_lowpan ieee802154_lowpan;
129 #if defined(CONFIG_IP_SCTP) || defined(CONFIG_IP_SCTP_MODULE)
130 struct netns_sctp sctp;
132 #ifdef CONFIG_NETFILTER
135 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
138 #if defined(CONFIG_NF_TABLES) || defined(CONFIG_NF_TABLES_MODULE)
139 struct netns_nftables nft;
142 #ifdef CONFIG_WEXT_CORE
143 struct sk_buff_head wext_nlevents;
145 struct net_generic __rcu *gen;
147 /* Used to store attached BPF programs */
148 struct netns_bpf bpf;
150 /* Note : following structs are cache line aligned */
152 struct netns_xfrm xfrm;
155 u64 net_cookie; /* written once */
157 #if IS_ENABLED(CONFIG_IP_VS)
158 struct netns_ipvs *ipvs;
160 #if IS_ENABLED(CONFIG_MPLS)
161 struct netns_mpls mpls;
163 #if IS_ENABLED(CONFIG_CAN)
164 struct netns_can can;
166 #ifdef CONFIG_XDP_SOCKETS
167 struct netns_xdp xdp;
169 #if IS_ENABLED(CONFIG_CRYPTO_USER)
170 struct sock *crypto_nlsk;
172 struct sock *diag_nlsk;
173 } __randomize_layout;
175 #include <linux/seq_file_net.h>
177 /* Init's network namespace */
178 extern struct net init_net;
181 struct net *copy_net_ns(unsigned long flags, struct user_namespace *user_ns,
182 struct net *old_net);
184 void net_ns_get_ownership(const struct net *net, kuid_t *uid, kgid_t *gid);
186 void net_ns_barrier(void);
187 #else /* CONFIG_NET_NS */
188 #include <linux/sched.h>
189 #include <linux/nsproxy.h>
190 static inline struct net *copy_net_ns(unsigned long flags,
191 struct user_namespace *user_ns, struct net *old_net)
193 if (flags & CLONE_NEWNET)
194 return ERR_PTR(-EINVAL);
198 static inline void net_ns_get_ownership(const struct net *net,
199 kuid_t *uid, kgid_t *gid)
201 *uid = GLOBAL_ROOT_UID;
202 *gid = GLOBAL_ROOT_GID;
205 static inline void net_ns_barrier(void) {}
206 #endif /* CONFIG_NET_NS */
209 extern struct list_head net_namespace_list;
211 struct net *get_net_ns_by_pid(pid_t pid);
212 struct net *get_net_ns_by_fd(int fd);
215 void ipx_register_sysctl(void);
216 void ipx_unregister_sysctl(void);
218 #define ipx_register_sysctl()
219 #define ipx_unregister_sysctl()
223 void __put_net(struct net *net);
225 static inline struct net *get_net(struct net *net)
227 refcount_inc(&net->ns.count);
231 static inline struct net *maybe_get_net(struct net *net)
233 /* Used when we know struct net exists but we
234 * aren't guaranteed a previous reference count
235 * exists. If the reference count is zero this
236 * function fails and returns NULL.
238 if (!refcount_inc_not_zero(&net->ns.count))
243 static inline void put_net(struct net *net)
245 if (refcount_dec_and_test(&net->ns.count))
250 int net_eq(const struct net *net1, const struct net *net2)
255 static inline int check_net(const struct net *net)
257 return refcount_read(&net->ns.count) != 0;
260 void net_drop_ns(void *);
264 static inline struct net *get_net(struct net *net)
269 static inline void put_net(struct net *net)
273 static inline struct net *maybe_get_net(struct net *net)
279 int net_eq(const struct net *net1, const struct net *net2)
284 static inline int check_net(const struct net *net)
289 #define net_drop_ns NULL
299 static inline void write_pnet(possible_net_t *pnet, struct net *net)
306 static inline struct net *read_pnet(const possible_net_t *pnet)
315 /* Protected by net_rwsem */
316 #define for_each_net(VAR) \
317 list_for_each_entry(VAR, &net_namespace_list, list)
318 #define for_each_net_continue_reverse(VAR) \
319 list_for_each_entry_continue_reverse(VAR, &net_namespace_list, list)
320 #define for_each_net_rcu(VAR) \
321 list_for_each_entry_rcu(VAR, &net_namespace_list, list)
326 #define __net_initdata
327 #define __net_initconst
329 #define __net_init __init
330 #define __net_exit __ref
331 #define __net_initdata __initdata
332 #define __net_initconst __initconst
335 int peernet2id_alloc(struct net *net, struct net *peer, gfp_t gfp);
336 int peernet2id(const struct net *net, struct net *peer);
337 bool peernet_has_id(const struct net *net, struct net *peer);
338 struct net *get_net_ns_by_id(const struct net *net, int id);
340 struct pernet_operations {
341 struct list_head list;
343 * Below methods are called without any exclusive locks.
344 * More than one net may be constructed and destructed
345 * in parallel on several cpus. Every pernet_operations
346 * have to keep in mind all other pernet_operations and
347 * to introduce a locking, if they share common resources.
349 * The only time they are called with exclusive lock is
350 * from register_pernet_subsys(), unregister_pernet_subsys()
351 * register_pernet_device() and unregister_pernet_device().
353 * Exit methods using blocking RCU primitives, such as
354 * synchronize_rcu(), should be implemented via exit_batch.
355 * Then, destruction of a group of net requires single
356 * synchronize_rcu() related to these pernet_operations,
357 * instead of separate synchronize_rcu() for every net.
358 * Please, avoid synchronize_rcu() at all, where it's possible.
360 * Note that a combination of pre_exit() and exit() can
361 * be used, since a synchronize_rcu() is guaranteed between
364 int (*init)(struct net *net);
365 void (*pre_exit)(struct net *net);
366 void (*exit)(struct net *net);
367 void (*exit_batch)(struct list_head *net_exit_list);
373 * Use these carefully. If you implement a network device and it
374 * needs per network namespace operations use device pernet operations,
375 * otherwise use pernet subsys operations.
377 * Network interfaces need to be removed from a dying netns _before_
378 * subsys notifiers can be called, as most of the network code cleanup
379 * (which is done from subsys notifiers) runs with the assumption that
380 * dev_remove_pack has been called so no new packets will arrive during
381 * and after the cleanup functions have been called. dev_remove_pack
382 * is not per namespace so instead the guarantee of no more packets
383 * arriving in a network namespace is provided by ensuring that all
384 * network devices and all sockets have left the network namespace
385 * before the cleanup methods are called.
387 * For the longest time the ipv4 icmp code was registered as a pernet
388 * device which caused kernel oops, and panics during network
389 * namespace cleanup. So please don't get this wrong.
391 int register_pernet_subsys(struct pernet_operations *);
392 void unregister_pernet_subsys(struct pernet_operations *);
393 int register_pernet_device(struct pernet_operations *);
394 void unregister_pernet_device(struct pernet_operations *);
399 int net_sysctl_init(void);
400 struct ctl_table_header *register_net_sysctl(struct net *net, const char *path,
401 struct ctl_table *table);
402 void unregister_net_sysctl_table(struct ctl_table_header *header);
404 static inline int net_sysctl_init(void) { return 0; }
405 static inline struct ctl_table_header *register_net_sysctl(struct net *net,
406 const char *path, struct ctl_table *table)
410 static inline void unregister_net_sysctl_table(struct ctl_table_header *header)
415 static inline int rt_genid_ipv4(const struct net *net)
417 return atomic_read(&net->ipv4.rt_genid);
420 #if IS_ENABLED(CONFIG_IPV6)
421 static inline int rt_genid_ipv6(const struct net *net)
423 return atomic_read(&net->ipv6.fib6_sernum);
427 static inline void rt_genid_bump_ipv4(struct net *net)
429 atomic_inc(&net->ipv4.rt_genid);
432 extern void (*__fib6_flush_trees)(struct net *net);
433 static inline void rt_genid_bump_ipv6(struct net *net)
435 if (__fib6_flush_trees)
436 __fib6_flush_trees(net);
439 #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
440 static inline struct netns_ieee802154_lowpan *
441 net_ieee802154_lowpan(struct net *net)
443 return &net->ieee802154_lowpan;
447 /* For callers who don't really care about whether it's IPv4 or IPv6 */
448 static inline void rt_genid_bump_all(struct net *net)
450 rt_genid_bump_ipv4(net);
451 rt_genid_bump_ipv6(net);
454 static inline int fnhe_genid(const struct net *net)
456 return atomic_read(&net->fnhe_genid);
459 static inline void fnhe_genid_bump(struct net *net)
461 atomic_inc(&net->fnhe_genid);
464 #endif /* __NET_NET_NAMESPACE_H */