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 #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 <net/netns/xdp.h>
34 #include <net/netns/smc.h>
35 #include <net/netns/bpf.h>
36 #include <net/netns/mctp.h>
37 #include <net/net_trackers.h>
38 #include <linux/ns_common.h>
39 #include <linux/idr.h>
40 #include <linux/skbuff.h>
41 #include <linux/notifier.h>
43 struct user_namespace;
44 struct proc_dir_entry;
47 struct ctl_table_header;
54 #define NETDEV_HASHBITS 8
55 #define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS)
58 /* First cache line can be often dirtied.
59 * Do not place here read-mostly fields.
61 refcount_t passive; /* To decide when the network
62 * namespace should be freed.
64 spinlock_t rules_mod_lock;
66 unsigned int dev_unreg_count;
68 unsigned int dev_base_seq; /* protected by rtnl_mutex */
74 struct list_head list; /* list of network namespaces */
75 struct list_head exit_list; /* To linked to call pernet exit
76 * methods on dead net (
77 * pernet_ops_rwsem read locked),
78 * or to unregister pernet ops
79 * (pernet_ops_rwsem write locked).
81 struct llist_node cleanup_list; /* namespaces on death row */
84 struct key_tag *key_domain; /* Key domain of operation tag */
86 struct user_namespace *user_ns; /* Owning user namespace */
87 struct ucounts *ucounts;
91 struct ref_tracker_dir refcnt_tracker;
93 struct list_head dev_base_head;
94 struct proc_dir_entry *proc_net;
95 struct proc_dir_entry *proc_net_stat;
98 struct ctl_table_set sysctls;
101 struct sock *rtnl; /* rtnetlink socket */
102 struct sock *genl_sock;
104 struct uevent_sock *uevent_sock; /* uevent socket */
106 struct hlist_head *dev_name_head;
107 struct hlist_head *dev_index_head;
108 struct raw_notifier_head netdev_chain;
110 /* Note that @hash_mix can be read millions times per second,
111 * it is critical that it is on a read_mostly cache line.
115 struct net_device *loopback_dev; /* The loopback */
118 struct list_head rules_ops;
120 struct netns_core core;
121 struct netns_mib mib;
122 struct netns_packet packet;
123 struct netns_unix unx;
124 struct netns_nexthop nexthop;
125 struct netns_ipv4 ipv4;
126 #if IS_ENABLED(CONFIG_IPV6)
127 struct netns_ipv6 ipv6;
129 #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
130 struct netns_ieee802154_lowpan ieee802154_lowpan;
132 #if defined(CONFIG_IP_SCTP) || defined(CONFIG_IP_SCTP_MODULE)
133 struct netns_sctp sctp;
135 #ifdef CONFIG_NETFILTER
137 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
140 #if defined(CONFIG_NF_TABLES) || defined(CONFIG_NF_TABLES_MODULE)
141 struct netns_nftables nft;
144 #ifdef CONFIG_WEXT_CORE
145 struct sk_buff_head wext_nlevents;
147 struct net_generic __rcu *gen;
149 /* Used to store attached BPF programs */
150 struct netns_bpf bpf;
152 /* Note : following structs are cache line aligned */
154 struct netns_xfrm xfrm;
157 u64 net_cookie; /* written once */
159 #if IS_ENABLED(CONFIG_IP_VS)
160 struct netns_ipvs *ipvs;
162 #if IS_ENABLED(CONFIG_MPLS)
163 struct netns_mpls mpls;
165 #if IS_ENABLED(CONFIG_CAN)
166 struct netns_can can;
168 #ifdef CONFIG_XDP_SOCKETS
169 struct netns_xdp xdp;
171 #if IS_ENABLED(CONFIG_MCTP)
172 struct netns_mctp mctp;
174 #if IS_ENABLED(CONFIG_CRYPTO_USER)
175 struct sock *crypto_nlsk;
177 struct sock *diag_nlsk;
178 #if IS_ENABLED(CONFIG_SMC)
179 struct netns_smc smc;
181 } __randomize_layout;
183 #include <linux/seq_file_net.h>
185 /* Init's network namespace */
186 extern struct net init_net;
189 struct net *copy_net_ns(unsigned long flags, struct user_namespace *user_ns,
190 struct net *old_net);
192 void net_ns_get_ownership(const struct net *net, kuid_t *uid, kgid_t *gid);
194 void net_ns_barrier(void);
196 struct ns_common *get_net_ns(struct ns_common *ns);
197 struct net *get_net_ns_by_fd(int fd);
198 #else /* CONFIG_NET_NS */
199 #include <linux/sched.h>
200 #include <linux/nsproxy.h>
201 static inline struct net *copy_net_ns(unsigned long flags,
202 struct user_namespace *user_ns, struct net *old_net)
204 if (flags & CLONE_NEWNET)
205 return ERR_PTR(-EINVAL);
209 static inline void net_ns_get_ownership(const struct net *net,
210 kuid_t *uid, kgid_t *gid)
212 *uid = GLOBAL_ROOT_UID;
213 *gid = GLOBAL_ROOT_GID;
216 static inline void net_ns_barrier(void) {}
218 static inline struct ns_common *get_net_ns(struct ns_common *ns)
220 return ERR_PTR(-EINVAL);
223 static inline struct net *get_net_ns_by_fd(int fd)
225 return ERR_PTR(-EINVAL);
227 #endif /* CONFIG_NET_NS */
230 extern struct list_head net_namespace_list;
232 struct net *get_net_ns_by_pid(pid_t pid);
235 void ipx_register_sysctl(void);
236 void ipx_unregister_sysctl(void);
238 #define ipx_register_sysctl()
239 #define ipx_unregister_sysctl()
243 void __put_net(struct net *net);
245 /* Try using get_net_track() instead */
246 static inline struct net *get_net(struct net *net)
248 refcount_inc(&net->ns.count);
252 static inline struct net *maybe_get_net(struct net *net)
254 /* Used when we know struct net exists but we
255 * aren't guaranteed a previous reference count
256 * exists. If the reference count is zero this
257 * function fails and returns NULL.
259 if (!refcount_inc_not_zero(&net->ns.count))
264 /* Try using put_net_track() instead */
265 static inline void put_net(struct net *net)
267 if (refcount_dec_and_test(&net->ns.count))
272 int net_eq(const struct net *net1, const struct net *net2)
277 static inline int check_net(const struct net *net)
279 return refcount_read(&net->ns.count) != 0;
282 void net_drop_ns(void *);
286 static inline struct net *get_net(struct net *net)
291 static inline void put_net(struct net *net)
295 static inline struct net *maybe_get_net(struct net *net)
301 int net_eq(const struct net *net1, const struct net *net2)
306 static inline int check_net(const struct net *net)
311 #define net_drop_ns NULL
315 static inline void netns_tracker_alloc(struct net *net,
316 netns_tracker *tracker, gfp_t gfp)
318 #ifdef CONFIG_NET_NS_REFCNT_TRACKER
319 ref_tracker_alloc(&net->refcnt_tracker, tracker, gfp);
323 static inline void netns_tracker_free(struct net *net,
324 netns_tracker *tracker)
326 #ifdef CONFIG_NET_NS_REFCNT_TRACKER
327 ref_tracker_free(&net->refcnt_tracker, tracker);
331 static inline struct net *get_net_track(struct net *net,
332 netns_tracker *tracker, gfp_t gfp)
335 netns_tracker_alloc(net, tracker, gfp);
339 static inline void put_net_track(struct net *net, netns_tracker *tracker)
341 netns_tracker_free(net, tracker);
351 static inline void write_pnet(possible_net_t *pnet, struct net *net)
358 static inline struct net *read_pnet(const possible_net_t *pnet)
367 /* Protected by net_rwsem */
368 #define for_each_net(VAR) \
369 list_for_each_entry(VAR, &net_namespace_list, list)
370 #define for_each_net_continue_reverse(VAR) \
371 list_for_each_entry_continue_reverse(VAR, &net_namespace_list, list)
372 #define for_each_net_rcu(VAR) \
373 list_for_each_entry_rcu(VAR, &net_namespace_list, list)
378 #define __net_initdata
379 #define __net_initconst
381 #define __net_init __init
382 #define __net_exit __ref
383 #define __net_initdata __initdata
384 #define __net_initconst __initconst
387 int peernet2id_alloc(struct net *net, struct net *peer, gfp_t gfp);
388 int peernet2id(const struct net *net, struct net *peer);
389 bool peernet_has_id(const struct net *net, struct net *peer);
390 struct net *get_net_ns_by_id(const struct net *net, int id);
392 struct pernet_operations {
393 struct list_head list;
395 * Below methods are called without any exclusive locks.
396 * More than one net may be constructed and destructed
397 * in parallel on several cpus. Every pernet_operations
398 * have to keep in mind all other pernet_operations and
399 * to introduce a locking, if they share common resources.
401 * The only time they are called with exclusive lock is
402 * from register_pernet_subsys(), unregister_pernet_subsys()
403 * register_pernet_device() and unregister_pernet_device().
405 * Exit methods using blocking RCU primitives, such as
406 * synchronize_rcu(), should be implemented via exit_batch.
407 * Then, destruction of a group of net requires single
408 * synchronize_rcu() related to these pernet_operations,
409 * instead of separate synchronize_rcu() for every net.
410 * Please, avoid synchronize_rcu() at all, where it's possible.
412 * Note that a combination of pre_exit() and exit() can
413 * be used, since a synchronize_rcu() is guaranteed between
416 int (*init)(struct net *net);
417 void (*pre_exit)(struct net *net);
418 void (*exit)(struct net *net);
419 void (*exit_batch)(struct list_head *net_exit_list);
425 * Use these carefully. If you implement a network device and it
426 * needs per network namespace operations use device pernet operations,
427 * otherwise use pernet subsys operations.
429 * Network interfaces need to be removed from a dying netns _before_
430 * subsys notifiers can be called, as most of the network code cleanup
431 * (which is done from subsys notifiers) runs with the assumption that
432 * dev_remove_pack has been called so no new packets will arrive during
433 * and after the cleanup functions have been called. dev_remove_pack
434 * is not per namespace so instead the guarantee of no more packets
435 * arriving in a network namespace is provided by ensuring that all
436 * network devices and all sockets have left the network namespace
437 * before the cleanup methods are called.
439 * For the longest time the ipv4 icmp code was registered as a pernet
440 * device which caused kernel oops, and panics during network
441 * namespace cleanup. So please don't get this wrong.
443 int register_pernet_subsys(struct pernet_operations *);
444 void unregister_pernet_subsys(struct pernet_operations *);
445 int register_pernet_device(struct pernet_operations *);
446 void unregister_pernet_device(struct pernet_operations *);
451 int net_sysctl_init(void);
452 struct ctl_table_header *register_net_sysctl(struct net *net, const char *path,
453 struct ctl_table *table);
454 void unregister_net_sysctl_table(struct ctl_table_header *header);
456 static inline int net_sysctl_init(void) { return 0; }
457 static inline struct ctl_table_header *register_net_sysctl(struct net *net,
458 const char *path, struct ctl_table *table)
462 static inline void unregister_net_sysctl_table(struct ctl_table_header *header)
467 static inline int rt_genid_ipv4(const struct net *net)
469 return atomic_read(&net->ipv4.rt_genid);
472 #if IS_ENABLED(CONFIG_IPV6)
473 static inline int rt_genid_ipv6(const struct net *net)
475 return atomic_read(&net->ipv6.fib6_sernum);
479 static inline void rt_genid_bump_ipv4(struct net *net)
481 atomic_inc(&net->ipv4.rt_genid);
484 extern void (*__fib6_flush_trees)(struct net *net);
485 static inline void rt_genid_bump_ipv6(struct net *net)
487 if (__fib6_flush_trees)
488 __fib6_flush_trees(net);
491 #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
492 static inline struct netns_ieee802154_lowpan *
493 net_ieee802154_lowpan(struct net *net)
495 return &net->ieee802154_lowpan;
499 /* For callers who don't really care about whether it's IPv4 or IPv6 */
500 static inline void rt_genid_bump_all(struct net *net)
502 rt_genid_bump_ipv4(net);
503 rt_genid_bump_ipv6(net);
506 static inline int fnhe_genid(const struct net *net)
508 return atomic_read(&net->fnhe_genid);
511 static inline void fnhe_genid_bump(struct net *net)
513 atomic_inc(&net->fnhe_genid);
516 #endif /* __NET_NET_NAMESPACE_H */