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>
46 struct user_namespace;
47 struct proc_dir_entry;
50 struct ctl_table_header;
57 #define NETDEV_HASHBITS 8
58 #define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS)
61 /* First cache line can be often dirtied.
62 * Do not place here read-mostly fields.
64 refcount_t passive; /* To decide when the network
65 * namespace should be freed.
67 spinlock_t rules_mod_lock;
69 atomic_t dev_unreg_count;
71 unsigned int dev_base_seq; /* protected by rtnl_mutex */
77 struct list_head list; /* list of network namespaces */
78 struct list_head exit_list; /* To linked to call pernet exit
79 * methods on dead net (
80 * pernet_ops_rwsem read locked),
81 * or to unregister pernet ops
82 * (pernet_ops_rwsem write locked).
84 struct llist_node cleanup_list; /* namespaces on death row */
87 struct key_tag *key_domain; /* Key domain of operation tag */
89 struct user_namespace *user_ns; /* Owning user namespace */
90 struct ucounts *ucounts;
94 struct ref_tracker_dir refcnt_tracker;
96 struct list_head dev_base_head;
97 struct proc_dir_entry *proc_net;
98 struct proc_dir_entry *proc_net_stat;
101 struct ctl_table_set sysctls;
104 struct sock *rtnl; /* rtnetlink socket */
105 struct sock *genl_sock;
107 struct uevent_sock *uevent_sock; /* uevent socket */
109 struct hlist_head *dev_name_head;
110 struct hlist_head *dev_index_head;
111 struct raw_notifier_head netdev_chain;
113 /* Note that @hash_mix can be read millions times per second,
114 * it is critical that it is on a read_mostly cache line.
118 struct net_device *loopback_dev; /* The loopback */
121 struct list_head rules_ops;
123 struct netns_core core;
124 struct netns_mib mib;
125 struct netns_packet packet;
126 #if IS_ENABLED(CONFIG_UNIX)
127 struct netns_unix unx;
129 struct netns_nexthop nexthop;
130 struct netns_ipv4 ipv4;
131 #if IS_ENABLED(CONFIG_IPV6)
132 struct netns_ipv6 ipv6;
134 #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
135 struct netns_ieee802154_lowpan ieee802154_lowpan;
137 #if defined(CONFIG_IP_SCTP) || defined(CONFIG_IP_SCTP_MODULE)
138 struct netns_sctp sctp;
140 #ifdef CONFIG_NETFILTER
142 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
145 #if defined(CONFIG_NF_TABLES) || defined(CONFIG_NF_TABLES_MODULE)
146 struct netns_nftables nft;
148 #if IS_ENABLED(CONFIG_NF_FLOW_TABLE)
152 #ifdef CONFIG_WEXT_CORE
153 struct sk_buff_head wext_nlevents;
155 struct net_generic __rcu *gen;
157 /* Used to store attached BPF programs */
158 struct netns_bpf bpf;
160 /* Note : following structs are cache line aligned */
162 struct netns_xfrm xfrm;
165 u64 net_cookie; /* written once */
167 #if IS_ENABLED(CONFIG_IP_VS)
168 struct netns_ipvs *ipvs;
170 #if IS_ENABLED(CONFIG_MPLS)
171 struct netns_mpls mpls;
173 #if IS_ENABLED(CONFIG_CAN)
174 struct netns_can can;
176 #ifdef CONFIG_XDP_SOCKETS
177 struct netns_xdp xdp;
179 #if IS_ENABLED(CONFIG_MCTP)
180 struct netns_mctp mctp;
182 #if IS_ENABLED(CONFIG_CRYPTO_USER)
183 struct sock *crypto_nlsk;
185 struct sock *diag_nlsk;
186 #if IS_ENABLED(CONFIG_SMC)
187 struct netns_smc smc;
189 } __randomize_layout;
191 #include <linux/seq_file_net.h>
193 /* Init's network namespace */
194 extern struct net init_net;
197 struct net *copy_net_ns(unsigned long flags, struct user_namespace *user_ns,
198 struct net *old_net);
200 void net_ns_get_ownership(const struct net *net, kuid_t *uid, kgid_t *gid);
202 void net_ns_barrier(void);
204 struct ns_common *get_net_ns(struct ns_common *ns);
205 struct net *get_net_ns_by_fd(int fd);
206 #else /* CONFIG_NET_NS */
207 #include <linux/sched.h>
208 #include <linux/nsproxy.h>
209 static inline struct net *copy_net_ns(unsigned long flags,
210 struct user_namespace *user_ns, struct net *old_net)
212 if (flags & CLONE_NEWNET)
213 return ERR_PTR(-EINVAL);
217 static inline void net_ns_get_ownership(const struct net *net,
218 kuid_t *uid, kgid_t *gid)
220 *uid = GLOBAL_ROOT_UID;
221 *gid = GLOBAL_ROOT_GID;
224 static inline void net_ns_barrier(void) {}
226 static inline struct ns_common *get_net_ns(struct ns_common *ns)
228 return ERR_PTR(-EINVAL);
231 static inline struct net *get_net_ns_by_fd(int fd)
233 return ERR_PTR(-EINVAL);
235 #endif /* CONFIG_NET_NS */
238 extern struct list_head net_namespace_list;
240 struct net *get_net_ns_by_pid(pid_t pid);
243 void ipx_register_sysctl(void);
244 void ipx_unregister_sysctl(void);
246 #define ipx_register_sysctl()
247 #define ipx_unregister_sysctl()
251 void __put_net(struct net *net);
253 /* Try using get_net_track() instead */
254 static inline struct net *get_net(struct net *net)
256 refcount_inc(&net->ns.count);
260 static inline struct net *maybe_get_net(struct net *net)
262 /* Used when we know struct net exists but we
263 * aren't guaranteed a previous reference count
264 * exists. If the reference count is zero this
265 * function fails and returns NULL.
267 if (!refcount_inc_not_zero(&net->ns.count))
272 /* Try using put_net_track() instead */
273 static inline void put_net(struct net *net)
275 if (refcount_dec_and_test(&net->ns.count))
280 int net_eq(const struct net *net1, const struct net *net2)
285 static inline int check_net(const struct net *net)
287 return refcount_read(&net->ns.count) != 0;
290 void net_drop_ns(void *);
294 static inline struct net *get_net(struct net *net)
299 static inline void put_net(struct net *net)
303 static inline struct net *maybe_get_net(struct net *net)
309 int net_eq(const struct net *net1, const struct net *net2)
314 static inline int check_net(const struct net *net)
319 #define net_drop_ns NULL
323 static inline void netns_tracker_alloc(struct net *net,
324 netns_tracker *tracker, gfp_t gfp)
326 #ifdef CONFIG_NET_NS_REFCNT_TRACKER
327 ref_tracker_alloc(&net->refcnt_tracker, tracker, gfp);
331 static inline void netns_tracker_free(struct net *net,
332 netns_tracker *tracker)
334 #ifdef CONFIG_NET_NS_REFCNT_TRACKER
335 ref_tracker_free(&net->refcnt_tracker, tracker);
339 static inline struct net *get_net_track(struct net *net,
340 netns_tracker *tracker, gfp_t gfp)
343 netns_tracker_alloc(net, tracker, gfp);
347 static inline void put_net_track(struct net *net, netns_tracker *tracker)
349 netns_tracker_free(net, tracker);
359 static inline void write_pnet(possible_net_t *pnet, struct net *net)
366 static inline struct net *read_pnet(const possible_net_t *pnet)
375 /* Protected by net_rwsem */
376 #define for_each_net(VAR) \
377 list_for_each_entry(VAR, &net_namespace_list, list)
378 #define for_each_net_continue_reverse(VAR) \
379 list_for_each_entry_continue_reverse(VAR, &net_namespace_list, list)
380 #define for_each_net_rcu(VAR) \
381 list_for_each_entry_rcu(VAR, &net_namespace_list, list)
386 #define __net_initdata
387 #define __net_initconst
389 #define __net_init __init
390 #define __net_exit __ref
391 #define __net_initdata __initdata
392 #define __net_initconst __initconst
395 int peernet2id_alloc(struct net *net, struct net *peer, gfp_t gfp);
396 int peernet2id(const struct net *net, struct net *peer);
397 bool peernet_has_id(const struct net *net, struct net *peer);
398 struct net *get_net_ns_by_id(const struct net *net, int id);
400 struct pernet_operations {
401 struct list_head list;
403 * Below methods are called without any exclusive locks.
404 * More than one net may be constructed and destructed
405 * in parallel on several cpus. Every pernet_operations
406 * have to keep in mind all other pernet_operations and
407 * to introduce a locking, if they share common resources.
409 * The only time they are called with exclusive lock is
410 * from register_pernet_subsys(), unregister_pernet_subsys()
411 * register_pernet_device() and unregister_pernet_device().
413 * Exit methods using blocking RCU primitives, such as
414 * synchronize_rcu(), should be implemented via exit_batch.
415 * Then, destruction of a group of net requires single
416 * synchronize_rcu() related to these pernet_operations,
417 * instead of separate synchronize_rcu() for every net.
418 * Please, avoid synchronize_rcu() at all, where it's possible.
420 * Note that a combination of pre_exit() and exit() can
421 * be used, since a synchronize_rcu() is guaranteed between
424 int (*init)(struct net *net);
425 void (*pre_exit)(struct net *net);
426 void (*exit)(struct net *net);
427 void (*exit_batch)(struct list_head *net_exit_list);
433 * Use these carefully. If you implement a network device and it
434 * needs per network namespace operations use device pernet operations,
435 * otherwise use pernet subsys operations.
437 * Network interfaces need to be removed from a dying netns _before_
438 * subsys notifiers can be called, as most of the network code cleanup
439 * (which is done from subsys notifiers) runs with the assumption that
440 * dev_remove_pack has been called so no new packets will arrive during
441 * and after the cleanup functions have been called. dev_remove_pack
442 * is not per namespace so instead the guarantee of no more packets
443 * arriving in a network namespace is provided by ensuring that all
444 * network devices and all sockets have left the network namespace
445 * before the cleanup methods are called.
447 * For the longest time the ipv4 icmp code was registered as a pernet
448 * device which caused kernel oops, and panics during network
449 * namespace cleanup. So please don't get this wrong.
451 int register_pernet_subsys(struct pernet_operations *);
452 void unregister_pernet_subsys(struct pernet_operations *);
453 int register_pernet_device(struct pernet_operations *);
454 void unregister_pernet_device(struct pernet_operations *);
459 int net_sysctl_init(void);
460 struct ctl_table_header *register_net_sysctl(struct net *net, const char *path,
461 struct ctl_table *table);
462 void unregister_net_sysctl_table(struct ctl_table_header *header);
464 static inline int net_sysctl_init(void) { return 0; }
465 static inline struct ctl_table_header *register_net_sysctl(struct net *net,
466 const char *path, struct ctl_table *table)
470 static inline void unregister_net_sysctl_table(struct ctl_table_header *header)
475 static inline int rt_genid_ipv4(const struct net *net)
477 return atomic_read(&net->ipv4.rt_genid);
480 #if IS_ENABLED(CONFIG_IPV6)
481 static inline int rt_genid_ipv6(const struct net *net)
483 return atomic_read(&net->ipv6.fib6_sernum);
487 static inline void rt_genid_bump_ipv4(struct net *net)
489 atomic_inc(&net->ipv4.rt_genid);
492 extern void (*__fib6_flush_trees)(struct net *net);
493 static inline void rt_genid_bump_ipv6(struct net *net)
495 if (__fib6_flush_trees)
496 __fib6_flush_trees(net);
499 #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
500 static inline struct netns_ieee802154_lowpan *
501 net_ieee802154_lowpan(struct net *net)
503 return &net->ieee802154_lowpan;
507 /* For callers who don't really care about whether it's IPv4 or IPv6 */
508 static inline void rt_genid_bump_all(struct net *net)
510 rt_genid_bump_ipv4(net);
511 rt_genid_bump_ipv6(net);
514 static inline int fnhe_genid(const struct net *net)
516 return atomic_read(&net->fnhe_genid);
519 static inline void fnhe_genid_bump(struct net *net)
521 atomic_inc(&net->fnhe_genid);
525 void net_ns_init(void);
527 static inline void net_ns_init(void) {}
530 #endif /* __NET_NET_NAMESPACE_H */