Loading...
1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Operations on the network namespace
4 */
5#ifndef __NET_NET_NAMESPACE_H
6#define __NET_NET_NAMESPACE_H
7
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
14#include <net/flow.h>
15#include <net/netns/core.h>
16#include <net/netns/mib.h>
17#include <net/netns/unix.h>
18#include <net/netns/packet.h>
19#include <net/netns/ipv4.h>
20#include <net/netns/ipv6.h>
21#include <net/netns/ieee802154_6lowpan.h>
22#include <net/netns/sctp.h>
23#include <net/netns/dccp.h>
24#include <net/netns/netfilter.h>
25#include <net/netns/x_tables.h>
26#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
27#include <net/netns/conntrack.h>
28#endif
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 <linux/ns_common.h>
34#include <linux/idr.h>
35#include <linux/skbuff.h>
36
37struct user_namespace;
38struct proc_dir_entry;
39struct net_device;
40struct sock;
41struct ctl_table_header;
42struct net_generic;
43struct uevent_sock;
44struct netns_ipvs;
45
46
47#define NETDEV_HASHBITS 8
48#define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS)
49
50struct net {
51 refcount_t passive; /* To decided when the network
52 * namespace should be freed.
53 */
54 refcount_t count; /* To decided when the network
55 * namespace should be shut down.
56 */
57 spinlock_t rules_mod_lock;
58
59 atomic64_t cookie_gen;
60
61 struct list_head list; /* list of network namespaces */
62 struct list_head exit_list; /* To linked to call pernet exit
63 * methods on dead net (
64 * pernet_ops_rwsem read locked),
65 * or to unregister pernet ops
66 * (pernet_ops_rwsem write locked).
67 */
68 struct llist_node cleanup_list; /* namespaces on death row */
69
70 struct user_namespace *user_ns; /* Owning user namespace */
71 struct ucounts *ucounts;
72 spinlock_t nsid_lock;
73 struct idr netns_ids;
74
75 struct ns_common ns;
76
77 struct proc_dir_entry *proc_net;
78 struct proc_dir_entry *proc_net_stat;
79
80#ifdef CONFIG_SYSCTL
81 struct ctl_table_set sysctls;
82#endif
83
84 struct sock *rtnl; /* rtnetlink socket */
85 struct sock *genl_sock;
86
87 struct uevent_sock *uevent_sock; /* uevent socket */
88
89 struct list_head dev_base_head;
90 struct hlist_head *dev_name_head;
91 struct hlist_head *dev_index_head;
92 unsigned int dev_base_seq; /* protected by rtnl_mutex */
93 int ifindex;
94 unsigned int dev_unreg_count;
95
96 /* core fib_rules */
97 struct list_head rules_ops;
98
99 struct list_head fib_notifier_ops; /* Populated by
100 * register_pernet_subsys()
101 */
102 struct net_device *loopback_dev; /* The loopback */
103 struct netns_core core;
104 struct netns_mib mib;
105 struct netns_packet packet;
106 struct netns_unix unx;
107 struct netns_ipv4 ipv4;
108#if IS_ENABLED(CONFIG_IPV6)
109 struct netns_ipv6 ipv6;
110#endif
111#if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
112 struct netns_ieee802154_lowpan ieee802154_lowpan;
113#endif
114#if defined(CONFIG_IP_SCTP) || defined(CONFIG_IP_SCTP_MODULE)
115 struct netns_sctp sctp;
116#endif
117#if defined(CONFIG_IP_DCCP) || defined(CONFIG_IP_DCCP_MODULE)
118 struct netns_dccp dccp;
119#endif
120#ifdef CONFIG_NETFILTER
121 struct netns_nf nf;
122 struct netns_xt xt;
123#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
124 struct netns_ct ct;
125#endif
126#if defined(CONFIG_NF_TABLES) || defined(CONFIG_NF_TABLES_MODULE)
127 struct netns_nftables nft;
128#endif
129#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
130 struct netns_nf_frag nf_frag;
131#endif
132 struct sock *nfnl;
133 struct sock *nfnl_stash;
134#if IS_ENABLED(CONFIG_NETFILTER_NETLINK_ACCT)
135 struct list_head nfnl_acct_list;
136#endif
137#if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
138 struct list_head nfct_timeout_list;
139#endif
140#endif
141#ifdef CONFIG_WEXT_CORE
142 struct sk_buff_head wext_nlevents;
143#endif
144 struct net_generic __rcu *gen;
145
146 /* Note : following structs are cache line aligned */
147#ifdef CONFIG_XFRM
148 struct netns_xfrm xfrm;
149#endif
150#if IS_ENABLED(CONFIG_IP_VS)
151 struct netns_ipvs *ipvs;
152#endif
153#if IS_ENABLED(CONFIG_MPLS)
154 struct netns_mpls mpls;
155#endif
156#if IS_ENABLED(CONFIG_CAN)
157 struct netns_can can;
158#endif
159 struct sock *diag_nlsk;
160 atomic_t fnhe_genid;
161} __randomize_layout;
162
163#include <linux/seq_file_net.h>
164
165/* Init's network namespace */
166extern struct net init_net;
167
168#ifdef CONFIG_NET_NS
169struct net *copy_net_ns(unsigned long flags, struct user_namespace *user_ns,
170 struct net *old_net);
171
172void net_ns_barrier(void);
173#else /* CONFIG_NET_NS */
174#include <linux/sched.h>
175#include <linux/nsproxy.h>
176static inline struct net *copy_net_ns(unsigned long flags,
177 struct user_namespace *user_ns, struct net *old_net)
178{
179 if (flags & CLONE_NEWNET)
180 return ERR_PTR(-EINVAL);
181 return old_net;
182}
183
184static inline void net_ns_barrier(void) {}
185#endif /* CONFIG_NET_NS */
186
187
188extern struct list_head net_namespace_list;
189
190struct net *get_net_ns_by_pid(pid_t pid);
191struct net *get_net_ns_by_fd(int fd);
192
193#ifdef CONFIG_SYSCTL
194void ipx_register_sysctl(void);
195void ipx_unregister_sysctl(void);
196#else
197#define ipx_register_sysctl()
198#define ipx_unregister_sysctl()
199#endif
200
201#ifdef CONFIG_NET_NS
202void __put_net(struct net *net);
203
204static inline struct net *get_net(struct net *net)
205{
206 refcount_inc(&net->count);
207 return net;
208}
209
210static inline struct net *maybe_get_net(struct net *net)
211{
212 /* Used when we know struct net exists but we
213 * aren't guaranteed a previous reference count
214 * exists. If the reference count is zero this
215 * function fails and returns NULL.
216 */
217 if (!refcount_inc_not_zero(&net->count))
218 net = NULL;
219 return net;
220}
221
222static inline void put_net(struct net *net)
223{
224 if (refcount_dec_and_test(&net->count))
225 __put_net(net);
226}
227
228static inline
229int net_eq(const struct net *net1, const struct net *net2)
230{
231 return net1 == net2;
232}
233
234static inline int check_net(const struct net *net)
235{
236 return refcount_read(&net->count) != 0;
237}
238
239void net_drop_ns(void *);
240
241#else
242
243static inline struct net *get_net(struct net *net)
244{
245 return net;
246}
247
248static inline void put_net(struct net *net)
249{
250}
251
252static inline struct net *maybe_get_net(struct net *net)
253{
254 return net;
255}
256
257static inline
258int net_eq(const struct net *net1, const struct net *net2)
259{
260 return 1;
261}
262
263static inline int check_net(const struct net *net)
264{
265 return 1;
266}
267
268#define net_drop_ns NULL
269#endif
270
271
272typedef struct {
273#ifdef CONFIG_NET_NS
274 struct net *net;
275#endif
276} possible_net_t;
277
278static inline void write_pnet(possible_net_t *pnet, struct net *net)
279{
280#ifdef CONFIG_NET_NS
281 pnet->net = net;
282#endif
283}
284
285static inline struct net *read_pnet(const possible_net_t *pnet)
286{
287#ifdef CONFIG_NET_NS
288 return pnet->net;
289#else
290 return &init_net;
291#endif
292}
293
294/* Protected by net_rwsem */
295#define for_each_net(VAR) \
296 list_for_each_entry(VAR, &net_namespace_list, list)
297
298#define for_each_net_rcu(VAR) \
299 list_for_each_entry_rcu(VAR, &net_namespace_list, list)
300
301#ifdef CONFIG_NET_NS
302#define __net_init
303#define __net_exit
304#define __net_initdata
305#define __net_initconst
306#else
307#define __net_init __init
308#define __net_exit __ref
309#define __net_initdata __initdata
310#define __net_initconst __initconst
311#endif
312
313int peernet2id_alloc(struct net *net, struct net *peer);
314int peernet2id(struct net *net, struct net *peer);
315bool peernet_has_id(struct net *net, struct net *peer);
316struct net *get_net_ns_by_id(struct net *net, int id);
317
318struct pernet_operations {
319 struct list_head list;
320 /*
321 * Below methods are called without any exclusive locks.
322 * More than one net may be constructed and destructed
323 * in parallel on several cpus. Every pernet_operations
324 * have to keep in mind all other pernet_operations and
325 * to introduce a locking, if they share common resources.
326 *
327 * The only time they are called with exclusive lock is
328 * from register_pernet_subsys(), unregister_pernet_subsys()
329 * register_pernet_device() and unregister_pernet_device().
330 *
331 * Exit methods using blocking RCU primitives, such as
332 * synchronize_rcu(), should be implemented via exit_batch.
333 * Then, destruction of a group of net requires single
334 * synchronize_rcu() related to these pernet_operations,
335 * instead of separate synchronize_rcu() for every net.
336 * Please, avoid synchronize_rcu() at all, where it's possible.
337 */
338 int (*init)(struct net *net);
339 void (*exit)(struct net *net);
340 void (*exit_batch)(struct list_head *net_exit_list);
341 unsigned int *id;
342 size_t size;
343};
344
345/*
346 * Use these carefully. If you implement a network device and it
347 * needs per network namespace operations use device pernet operations,
348 * otherwise use pernet subsys operations.
349 *
350 * Network interfaces need to be removed from a dying netns _before_
351 * subsys notifiers can be called, as most of the network code cleanup
352 * (which is done from subsys notifiers) runs with the assumption that
353 * dev_remove_pack has been called so no new packets will arrive during
354 * and after the cleanup functions have been called. dev_remove_pack
355 * is not per namespace so instead the guarantee of no more packets
356 * arriving in a network namespace is provided by ensuring that all
357 * network devices and all sockets have left the network namespace
358 * before the cleanup methods are called.
359 *
360 * For the longest time the ipv4 icmp code was registered as a pernet
361 * device which caused kernel oops, and panics during network
362 * namespace cleanup. So please don't get this wrong.
363 */
364int register_pernet_subsys(struct pernet_operations *);
365void unregister_pernet_subsys(struct pernet_operations *);
366int register_pernet_device(struct pernet_operations *);
367void unregister_pernet_device(struct pernet_operations *);
368
369struct ctl_table;
370struct ctl_table_header;
371
372#ifdef CONFIG_SYSCTL
373int net_sysctl_init(void);
374struct ctl_table_header *register_net_sysctl(struct net *net, const char *path,
375 struct ctl_table *table);
376void unregister_net_sysctl_table(struct ctl_table_header *header);
377#else
378static inline int net_sysctl_init(void) { return 0; }
379static inline struct ctl_table_header *register_net_sysctl(struct net *net,
380 const char *path, struct ctl_table *table)
381{
382 return NULL;
383}
384static inline void unregister_net_sysctl_table(struct ctl_table_header *header)
385{
386}
387#endif
388
389static inline int rt_genid_ipv4(struct net *net)
390{
391 return atomic_read(&net->ipv4.rt_genid);
392}
393
394static inline void rt_genid_bump_ipv4(struct net *net)
395{
396 atomic_inc(&net->ipv4.rt_genid);
397}
398
399extern void (*__fib6_flush_trees)(struct net *net);
400static inline void rt_genid_bump_ipv6(struct net *net)
401{
402 if (__fib6_flush_trees)
403 __fib6_flush_trees(net);
404}
405
406#if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
407static inline struct netns_ieee802154_lowpan *
408net_ieee802154_lowpan(struct net *net)
409{
410 return &net->ieee802154_lowpan;
411}
412#endif
413
414/* For callers who don't really care about whether it's IPv4 or IPv6 */
415static inline void rt_genid_bump_all(struct net *net)
416{
417 rt_genid_bump_ipv4(net);
418 rt_genid_bump_ipv6(net);
419}
420
421static inline int fnhe_genid(struct net *net)
422{
423 return atomic_read(&net->fnhe_genid);
424}
425
426static inline void fnhe_genid_bump(struct net *net)
427{
428 atomic_inc(&net->fnhe_genid);
429}
430
431#endif /* __NET_NET_NAMESPACE_H */
1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Operations on the network namespace
4 */
5#ifndef __NET_NET_NAMESPACE_H
6#define __NET_NET_NAMESPACE_H
7
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>
14
15#include <net/flow.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>
29#endif
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/smc.h>
36#include <net/netns/bpf.h>
37#include <linux/ns_common.h>
38#include <linux/idr.h>
39#include <linux/skbuff.h>
40#include <linux/notifier.h>
41
42struct user_namespace;
43struct proc_dir_entry;
44struct net_device;
45struct sock;
46struct ctl_table_header;
47struct net_generic;
48struct uevent_sock;
49struct netns_ipvs;
50struct bpf_prog;
51
52
53#define NETDEV_HASHBITS 8
54#define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS)
55
56struct net {
57 /* First cache line can be often dirtied.
58 * Do not place here read-mostly fields.
59 */
60 refcount_t passive; /* To decide when the network
61 * namespace should be freed.
62 */
63 spinlock_t rules_mod_lock;
64
65 unsigned int dev_unreg_count;
66
67 unsigned int dev_base_seq; /* protected by rtnl_mutex */
68 int ifindex;
69
70 spinlock_t nsid_lock;
71 atomic_t fnhe_genid;
72
73 struct list_head list; /* list of network namespaces */
74 struct list_head exit_list; /* To linked to call pernet exit
75 * methods on dead net (
76 * pernet_ops_rwsem read locked),
77 * or to unregister pernet ops
78 * (pernet_ops_rwsem write locked).
79 */
80 struct llist_node cleanup_list; /* namespaces on death row */
81
82#ifdef CONFIG_KEYS
83 struct key_tag *key_domain; /* Key domain of operation tag */
84#endif
85 struct user_namespace *user_ns; /* Owning user namespace */
86 struct ucounts *ucounts;
87 struct idr netns_ids;
88
89 struct ns_common ns;
90
91 struct list_head dev_base_head;
92 struct proc_dir_entry *proc_net;
93 struct proc_dir_entry *proc_net_stat;
94
95#ifdef CONFIG_SYSCTL
96 struct ctl_table_set sysctls;
97#endif
98
99 struct sock *rtnl; /* rtnetlink socket */
100 struct sock *genl_sock;
101
102 struct uevent_sock *uevent_sock; /* uevent socket */
103
104 struct hlist_head *dev_name_head;
105 struct hlist_head *dev_index_head;
106 struct raw_notifier_head netdev_chain;
107
108 /* Note that @hash_mix can be read millions times per second,
109 * it is critical that it is on a read_mostly cache line.
110 */
111 u32 hash_mix;
112
113 struct net_device *loopback_dev; /* The loopback */
114
115 /* core fib_rules */
116 struct list_head rules_ops;
117
118 struct netns_core core;
119 struct netns_mib mib;
120 struct netns_packet packet;
121 struct netns_unix unx;
122 struct netns_nexthop nexthop;
123 struct netns_ipv4 ipv4;
124#if IS_ENABLED(CONFIG_IPV6)
125 struct netns_ipv6 ipv6;
126#endif
127#if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
128 struct netns_ieee802154_lowpan ieee802154_lowpan;
129#endif
130#if defined(CONFIG_IP_SCTP) || defined(CONFIG_IP_SCTP_MODULE)
131 struct netns_sctp sctp;
132#endif
133#ifdef CONFIG_NETFILTER
134 struct netns_nf nf;
135 struct netns_xt xt;
136#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
137 struct netns_ct ct;
138#endif
139#if defined(CONFIG_NF_TABLES) || defined(CONFIG_NF_TABLES_MODULE)
140 struct netns_nftables nft;
141#endif
142#endif
143#ifdef CONFIG_WEXT_CORE
144 struct sk_buff_head wext_nlevents;
145#endif
146 struct net_generic __rcu *gen;
147
148 /* Used to store attached BPF programs */
149 struct netns_bpf bpf;
150
151 /* Note : following structs are cache line aligned */
152#ifdef CONFIG_XFRM
153 struct netns_xfrm xfrm;
154#endif
155
156 u64 net_cookie; /* written once */
157
158#if IS_ENABLED(CONFIG_IP_VS)
159 struct netns_ipvs *ipvs;
160#endif
161#if IS_ENABLED(CONFIG_MPLS)
162 struct netns_mpls mpls;
163#endif
164#if IS_ENABLED(CONFIG_CAN)
165 struct netns_can can;
166#endif
167#ifdef CONFIG_XDP_SOCKETS
168 struct netns_xdp xdp;
169#endif
170#if IS_ENABLED(CONFIG_CRYPTO_USER)
171 struct sock *crypto_nlsk;
172#endif
173 struct sock *diag_nlsk;
174#if IS_ENABLED(CONFIG_SMC)
175 struct netns_smc smc;
176#endif
177} __randomize_layout;
178
179#include <linux/seq_file_net.h>
180
181/* Init's network namespace */
182extern struct net init_net;
183
184#ifdef CONFIG_NET_NS
185struct net *copy_net_ns(unsigned long flags, struct user_namespace *user_ns,
186 struct net *old_net);
187
188void net_ns_get_ownership(const struct net *net, kuid_t *uid, kgid_t *gid);
189
190void net_ns_barrier(void);
191
192struct ns_common *get_net_ns(struct ns_common *ns);
193struct net *get_net_ns_by_fd(int fd);
194#else /* CONFIG_NET_NS */
195#include <linux/sched.h>
196#include <linux/nsproxy.h>
197static inline struct net *copy_net_ns(unsigned long flags,
198 struct user_namespace *user_ns, struct net *old_net)
199{
200 if (flags & CLONE_NEWNET)
201 return ERR_PTR(-EINVAL);
202 return old_net;
203}
204
205static inline void net_ns_get_ownership(const struct net *net,
206 kuid_t *uid, kgid_t *gid)
207{
208 *uid = GLOBAL_ROOT_UID;
209 *gid = GLOBAL_ROOT_GID;
210}
211
212static inline void net_ns_barrier(void) {}
213
214static inline struct ns_common *get_net_ns(struct ns_common *ns)
215{
216 return ERR_PTR(-EINVAL);
217}
218
219static inline struct net *get_net_ns_by_fd(int fd)
220{
221 return ERR_PTR(-EINVAL);
222}
223#endif /* CONFIG_NET_NS */
224
225
226extern struct list_head net_namespace_list;
227
228struct net *get_net_ns_by_pid(pid_t pid);
229
230#ifdef CONFIG_SYSCTL
231void ipx_register_sysctl(void);
232void ipx_unregister_sysctl(void);
233#else
234#define ipx_register_sysctl()
235#define ipx_unregister_sysctl()
236#endif
237
238#ifdef CONFIG_NET_NS
239void __put_net(struct net *net);
240
241static inline struct net *get_net(struct net *net)
242{
243 refcount_inc(&net->ns.count);
244 return net;
245}
246
247static inline struct net *maybe_get_net(struct net *net)
248{
249 /* Used when we know struct net exists but we
250 * aren't guaranteed a previous reference count
251 * exists. If the reference count is zero this
252 * function fails and returns NULL.
253 */
254 if (!refcount_inc_not_zero(&net->ns.count))
255 net = NULL;
256 return net;
257}
258
259static inline void put_net(struct net *net)
260{
261 if (refcount_dec_and_test(&net->ns.count))
262 __put_net(net);
263}
264
265static inline
266int net_eq(const struct net *net1, const struct net *net2)
267{
268 return net1 == net2;
269}
270
271static inline int check_net(const struct net *net)
272{
273 return refcount_read(&net->ns.count) != 0;
274}
275
276void net_drop_ns(void *);
277
278#else
279
280static inline struct net *get_net(struct net *net)
281{
282 return net;
283}
284
285static inline void put_net(struct net *net)
286{
287}
288
289static inline struct net *maybe_get_net(struct net *net)
290{
291 return net;
292}
293
294static inline
295int net_eq(const struct net *net1, const struct net *net2)
296{
297 return 1;
298}
299
300static inline int check_net(const struct net *net)
301{
302 return 1;
303}
304
305#define net_drop_ns NULL
306#endif
307
308
309typedef struct {
310#ifdef CONFIG_NET_NS
311 struct net *net;
312#endif
313} possible_net_t;
314
315static inline void write_pnet(possible_net_t *pnet, struct net *net)
316{
317#ifdef CONFIG_NET_NS
318 pnet->net = net;
319#endif
320}
321
322static inline struct net *read_pnet(const possible_net_t *pnet)
323{
324#ifdef CONFIG_NET_NS
325 return pnet->net;
326#else
327 return &init_net;
328#endif
329}
330
331/* Protected by net_rwsem */
332#define for_each_net(VAR) \
333 list_for_each_entry(VAR, &net_namespace_list, list)
334#define for_each_net_continue_reverse(VAR) \
335 list_for_each_entry_continue_reverse(VAR, &net_namespace_list, list)
336#define for_each_net_rcu(VAR) \
337 list_for_each_entry_rcu(VAR, &net_namespace_list, list)
338
339#ifdef CONFIG_NET_NS
340#define __net_init
341#define __net_exit
342#define __net_initdata
343#define __net_initconst
344#else
345#define __net_init __init
346#define __net_exit __ref
347#define __net_initdata __initdata
348#define __net_initconst __initconst
349#endif
350
351int peernet2id_alloc(struct net *net, struct net *peer, gfp_t gfp);
352int peernet2id(const struct net *net, struct net *peer);
353bool peernet_has_id(const struct net *net, struct net *peer);
354struct net *get_net_ns_by_id(const struct net *net, int id);
355
356struct pernet_operations {
357 struct list_head list;
358 /*
359 * Below methods are called without any exclusive locks.
360 * More than one net may be constructed and destructed
361 * in parallel on several cpus. Every pernet_operations
362 * have to keep in mind all other pernet_operations and
363 * to introduce a locking, if they share common resources.
364 *
365 * The only time they are called with exclusive lock is
366 * from register_pernet_subsys(), unregister_pernet_subsys()
367 * register_pernet_device() and unregister_pernet_device().
368 *
369 * Exit methods using blocking RCU primitives, such as
370 * synchronize_rcu(), should be implemented via exit_batch.
371 * Then, destruction of a group of net requires single
372 * synchronize_rcu() related to these pernet_operations,
373 * instead of separate synchronize_rcu() for every net.
374 * Please, avoid synchronize_rcu() at all, where it's possible.
375 *
376 * Note that a combination of pre_exit() and exit() can
377 * be used, since a synchronize_rcu() is guaranteed between
378 * the calls.
379 */
380 int (*init)(struct net *net);
381 void (*pre_exit)(struct net *net);
382 void (*exit)(struct net *net);
383 void (*exit_batch)(struct list_head *net_exit_list);
384 unsigned int *id;
385 size_t size;
386};
387
388/*
389 * Use these carefully. If you implement a network device and it
390 * needs per network namespace operations use device pernet operations,
391 * otherwise use pernet subsys operations.
392 *
393 * Network interfaces need to be removed from a dying netns _before_
394 * subsys notifiers can be called, as most of the network code cleanup
395 * (which is done from subsys notifiers) runs with the assumption that
396 * dev_remove_pack has been called so no new packets will arrive during
397 * and after the cleanup functions have been called. dev_remove_pack
398 * is not per namespace so instead the guarantee of no more packets
399 * arriving in a network namespace is provided by ensuring that all
400 * network devices and all sockets have left the network namespace
401 * before the cleanup methods are called.
402 *
403 * For the longest time the ipv4 icmp code was registered as a pernet
404 * device which caused kernel oops, and panics during network
405 * namespace cleanup. So please don't get this wrong.
406 */
407int register_pernet_subsys(struct pernet_operations *);
408void unregister_pernet_subsys(struct pernet_operations *);
409int register_pernet_device(struct pernet_operations *);
410void unregister_pernet_device(struct pernet_operations *);
411
412struct ctl_table;
413
414#ifdef CONFIG_SYSCTL
415int net_sysctl_init(void);
416struct ctl_table_header *register_net_sysctl(struct net *net, const char *path,
417 struct ctl_table *table);
418void unregister_net_sysctl_table(struct ctl_table_header *header);
419#else
420static inline int net_sysctl_init(void) { return 0; }
421static inline struct ctl_table_header *register_net_sysctl(struct net *net,
422 const char *path, struct ctl_table *table)
423{
424 return NULL;
425}
426static inline void unregister_net_sysctl_table(struct ctl_table_header *header)
427{
428}
429#endif
430
431static inline int rt_genid_ipv4(const struct net *net)
432{
433 return atomic_read(&net->ipv4.rt_genid);
434}
435
436#if IS_ENABLED(CONFIG_IPV6)
437static inline int rt_genid_ipv6(const struct net *net)
438{
439 return atomic_read(&net->ipv6.fib6_sernum);
440}
441#endif
442
443static inline void rt_genid_bump_ipv4(struct net *net)
444{
445 atomic_inc(&net->ipv4.rt_genid);
446}
447
448extern void (*__fib6_flush_trees)(struct net *net);
449static inline void rt_genid_bump_ipv6(struct net *net)
450{
451 if (__fib6_flush_trees)
452 __fib6_flush_trees(net);
453}
454
455#if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
456static inline struct netns_ieee802154_lowpan *
457net_ieee802154_lowpan(struct net *net)
458{
459 return &net->ieee802154_lowpan;
460}
461#endif
462
463/* For callers who don't really care about whether it's IPv4 or IPv6 */
464static inline void rt_genid_bump_all(struct net *net)
465{
466 rt_genid_bump_ipv4(net);
467 rt_genid_bump_ipv6(net);
468}
469
470static inline int fnhe_genid(const struct net *net)
471{
472 return atomic_read(&net->fnhe_genid);
473}
474
475static inline void fnhe_genid_bump(struct net *net)
476{
477 atomic_inc(&net->fnhe_genid);
478}
479
480#endif /* __NET_NET_NAMESPACE_H */