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/dccp.h>
26 #include <net/netns/netfilter.h>
27 #include <net/netns/x_tables.h>
28 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
29 #include <net/netns/conntrack.h>
31 #include <net/netns/nftables.h>
32 #include <net/netns/xfrm.h>
33 #include <net/netns/mpls.h>
34 #include <net/netns/can.h>
35 #include <net/netns/xdp.h>
36 #include <linux/ns_common.h>
37 #include <linux/idr.h>
38 #include <linux/skbuff.h>
40 struct user_namespace;
41 struct proc_dir_entry;
44 struct ctl_table_header;
51 #define NETDEV_HASHBITS 8
52 #define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS)
55 /* First cache line can be often dirtied.
56 * Do not place here read-mostly fields.
58 refcount_t passive; /* To decide when the network
59 * namespace should be freed.
61 refcount_t count; /* To decided when the network
62 * namespace should be shut down.
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;
92 struct list_head dev_base_head;
93 struct proc_dir_entry *proc_net;
94 struct proc_dir_entry *proc_net_stat;
97 struct ctl_table_set sysctls;
100 struct sock *rtnl; /* rtnetlink socket */
101 struct sock *genl_sock;
103 struct uevent_sock *uevent_sock; /* uevent socket */
105 struct hlist_head *dev_name_head;
106 struct hlist_head *dev_index_head;
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 #if defined(CONFIG_IP_DCCP) || defined(CONFIG_IP_DCCP_MODULE)
133 struct netns_dccp dccp;
135 #ifdef CONFIG_NETFILTER
138 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
141 #if defined(CONFIG_NF_TABLES) || defined(CONFIG_NF_TABLES_MODULE)
142 struct netns_nftables nft;
144 #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
145 struct netns_nf_frag nf_frag;
146 struct ctl_table_header *nf_frag_frags_hdr;
149 struct sock *nfnl_stash;
150 #if IS_ENABLED(CONFIG_NETFILTER_NETLINK_ACCT)
151 struct list_head nfnl_acct_list;
153 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
154 struct list_head nfct_timeout_list;
157 #ifdef CONFIG_WEXT_CORE
158 struct sk_buff_head wext_nlevents;
160 struct net_generic __rcu *gen;
162 struct bpf_prog __rcu *flow_dissector_prog;
164 /* Note : following structs are cache line aligned */
166 struct netns_xfrm xfrm;
168 #if IS_ENABLED(CONFIG_IP_VS)
169 struct netns_ipvs *ipvs;
171 #if IS_ENABLED(CONFIG_MPLS)
172 struct netns_mpls mpls;
174 #if IS_ENABLED(CONFIG_CAN)
175 struct netns_can can;
177 #ifdef CONFIG_XDP_SOCKETS
178 struct netns_xdp xdp;
180 #if IS_ENABLED(CONFIG_CRYPTO_USER)
181 struct sock *crypto_nlsk;
183 struct sock *diag_nlsk;
184 } __randomize_layout;
186 #include <linux/seq_file_net.h>
188 /* Init's network namespace */
189 extern struct net init_net;
192 struct net *copy_net_ns(unsigned long flags, struct user_namespace *user_ns,
193 struct net *old_net);
195 void net_ns_get_ownership(const struct net *net, kuid_t *uid, kgid_t *gid);
197 void net_ns_barrier(void);
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) {}
217 #endif /* CONFIG_NET_NS */
220 extern struct list_head net_namespace_list;
222 struct net *get_net_ns_by_pid(pid_t pid);
223 struct net *get_net_ns_by_fd(int fd);
226 void ipx_register_sysctl(void);
227 void ipx_unregister_sysctl(void);
229 #define ipx_register_sysctl()
230 #define ipx_unregister_sysctl()
234 void __put_net(struct net *net);
236 static inline struct net *get_net(struct net *net)
238 refcount_inc(&net->count);
242 static inline struct net *maybe_get_net(struct net *net)
244 /* Used when we know struct net exists but we
245 * aren't guaranteed a previous reference count
246 * exists. If the reference count is zero this
247 * function fails and returns NULL.
249 if (!refcount_inc_not_zero(&net->count))
254 static inline void put_net(struct net *net)
256 if (refcount_dec_and_test(&net->count))
261 int net_eq(const struct net *net1, const struct net *net2)
266 static inline int check_net(const struct net *net)
268 return refcount_read(&net->count) != 0;
271 void net_drop_ns(void *);
275 static inline struct net *get_net(struct net *net)
280 static inline void put_net(struct net *net)
284 static inline struct net *maybe_get_net(struct net *net)
290 int net_eq(const struct net *net1, const struct net *net2)
295 static inline int check_net(const struct net *net)
300 #define net_drop_ns NULL
310 static inline void write_pnet(possible_net_t *pnet, struct net *net)
317 static inline struct net *read_pnet(const possible_net_t *pnet)
326 /* Protected by net_rwsem */
327 #define for_each_net(VAR) \
328 list_for_each_entry(VAR, &net_namespace_list, list)
330 #define for_each_net_rcu(VAR) \
331 list_for_each_entry_rcu(VAR, &net_namespace_list, list)
336 #define __net_initdata
337 #define __net_initconst
339 #define __net_init __init
340 #define __net_exit __ref
341 #define __net_initdata __initdata
342 #define __net_initconst __initconst
345 int peernet2id_alloc(struct net *net, struct net *peer, gfp_t gfp);
346 int peernet2id(struct net *net, struct net *peer);
347 bool peernet_has_id(struct net *net, struct net *peer);
348 struct net *get_net_ns_by_id(struct net *net, int id);
350 struct pernet_operations {
351 struct list_head list;
353 * Below methods are called without any exclusive locks.
354 * More than one net may be constructed and destructed
355 * in parallel on several cpus. Every pernet_operations
356 * have to keep in mind all other pernet_operations and
357 * to introduce a locking, if they share common resources.
359 * The only time they are called with exclusive lock is
360 * from register_pernet_subsys(), unregister_pernet_subsys()
361 * register_pernet_device() and unregister_pernet_device().
363 * Exit methods using blocking RCU primitives, such as
364 * synchronize_rcu(), should be implemented via exit_batch.
365 * Then, destruction of a group of net requires single
366 * synchronize_rcu() related to these pernet_operations,
367 * instead of separate synchronize_rcu() for every net.
368 * Please, avoid synchronize_rcu() at all, where it's possible.
370 * Note that a combination of pre_exit() and exit() can
371 * be used, since a synchronize_rcu() is guaranteed between
374 int (*init)(struct net *net);
375 void (*pre_exit)(struct net *net);
376 void (*exit)(struct net *net);
377 void (*exit_batch)(struct list_head *net_exit_list);
383 * Use these carefully. If you implement a network device and it
384 * needs per network namespace operations use device pernet operations,
385 * otherwise use pernet subsys operations.
387 * Network interfaces need to be removed from a dying netns _before_
388 * subsys notifiers can be called, as most of the network code cleanup
389 * (which is done from subsys notifiers) runs with the assumption that
390 * dev_remove_pack has been called so no new packets will arrive during
391 * and after the cleanup functions have been called. dev_remove_pack
392 * is not per namespace so instead the guarantee of no more packets
393 * arriving in a network namespace is provided by ensuring that all
394 * network devices and all sockets have left the network namespace
395 * before the cleanup methods are called.
397 * For the longest time the ipv4 icmp code was registered as a pernet
398 * device which caused kernel oops, and panics during network
399 * namespace cleanup. So please don't get this wrong.
401 int register_pernet_subsys(struct pernet_operations *);
402 void unregister_pernet_subsys(struct pernet_operations *);
403 int register_pernet_device(struct pernet_operations *);
404 void unregister_pernet_device(struct pernet_operations *);
407 struct ctl_table_header;
410 int net_sysctl_init(void);
411 struct ctl_table_header *register_net_sysctl(struct net *net, const char *path,
412 struct ctl_table *table);
413 void unregister_net_sysctl_table(struct ctl_table_header *header);
415 static inline int net_sysctl_init(void) { return 0; }
416 static inline struct ctl_table_header *register_net_sysctl(struct net *net,
417 const char *path, struct ctl_table *table)
421 static inline void unregister_net_sysctl_table(struct ctl_table_header *header)
426 static inline int rt_genid_ipv4(struct net *net)
428 return atomic_read(&net->ipv4.rt_genid);
431 static inline void rt_genid_bump_ipv4(struct net *net)
433 atomic_inc(&net->ipv4.rt_genid);
436 extern void (*__fib6_flush_trees)(struct net *net);
437 static inline void rt_genid_bump_ipv6(struct net *net)
439 if (__fib6_flush_trees)
440 __fib6_flush_trees(net);
443 #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
444 static inline struct netns_ieee802154_lowpan *
445 net_ieee802154_lowpan(struct net *net)
447 return &net->ieee802154_lowpan;
451 /* For callers who don't really care about whether it's IPv4 or IPv6 */
452 static inline void rt_genid_bump_all(struct net *net)
454 rt_genid_bump_ipv4(net);
455 rt_genid_bump_ipv6(net);
458 static inline int fnhe_genid(struct net *net)
460 return atomic_read(&net->fnhe_genid);
463 static inline void fnhe_genid_bump(struct net *net)
465 atomic_inc(&net->fnhe_genid);
468 #endif /* __NET_NET_NAMESPACE_H */