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1/*
2 * Operations on the network namespace
3 */
4#ifndef __NET_NET_NAMESPACE_H
5#define __NET_NET_NAMESPACE_H
6
7#include <linux/atomic.h>
8#include <linux/workqueue.h>
9#include <linux/list.h>
10#include <linux/sysctl.h>
11
12#include <net/flow.h>
13#include <net/netns/core.h>
14#include <net/netns/mib.h>
15#include <net/netns/unix.h>
16#include <net/netns/packet.h>
17#include <net/netns/ipv4.h>
18#include <net/netns/ipv6.h>
19#include <net/netns/ieee802154_6lowpan.h>
20#include <net/netns/sctp.h>
21#include <net/netns/dccp.h>
22#include <net/netns/netfilter.h>
23#include <net/netns/x_tables.h>
24#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
25#include <net/netns/conntrack.h>
26#endif
27#include <net/netns/nftables.h>
28#include <net/netns/xfrm.h>
29#include <net/netns/mpls.h>
30#include <linux/ns_common.h>
31#include <linux/idr.h>
32#include <linux/skbuff.h>
33
34struct user_namespace;
35struct proc_dir_entry;
36struct net_device;
37struct sock;
38struct ctl_table_header;
39struct net_generic;
40struct sock;
41struct netns_ipvs;
42
43
44#define NETDEV_HASHBITS 8
45#define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS)
46
47struct net {
48 atomic_t passive; /* To decided when the network
49 * namespace should be freed.
50 */
51 atomic_t count; /* To decided when the network
52 * namespace should be shut down.
53 */
54 spinlock_t rules_mod_lock;
55
56 atomic64_t cookie_gen;
57
58 struct list_head list; /* list of network namespaces */
59 struct list_head cleanup_list; /* namespaces on death row */
60 struct list_head exit_list; /* Use only net_mutex */
61
62 struct user_namespace *user_ns; /* Owning user namespace */
63 spinlock_t nsid_lock;
64 struct idr netns_ids;
65
66 struct ns_common ns;
67
68 struct proc_dir_entry *proc_net;
69 struct proc_dir_entry *proc_net_stat;
70
71#ifdef CONFIG_SYSCTL
72 struct ctl_table_set sysctls;
73#endif
74
75 struct sock *rtnl; /* rtnetlink socket */
76 struct sock *genl_sock;
77
78 struct list_head dev_base_head;
79 struct hlist_head *dev_name_head;
80 struct hlist_head *dev_index_head;
81 unsigned int dev_base_seq; /* protected by rtnl_mutex */
82 int ifindex;
83 unsigned int dev_unreg_count;
84
85 /* core fib_rules */
86 struct list_head rules_ops;
87
88
89 struct net_device *loopback_dev; /* The loopback */
90 struct netns_core core;
91 struct netns_mib mib;
92 struct netns_packet packet;
93 struct netns_unix unx;
94 struct netns_ipv4 ipv4;
95#if IS_ENABLED(CONFIG_IPV6)
96 struct netns_ipv6 ipv6;
97#endif
98#if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
99 struct netns_ieee802154_lowpan ieee802154_lowpan;
100#endif
101#if defined(CONFIG_IP_SCTP) || defined(CONFIG_IP_SCTP_MODULE)
102 struct netns_sctp sctp;
103#endif
104#if defined(CONFIG_IP_DCCP) || defined(CONFIG_IP_DCCP_MODULE)
105 struct netns_dccp dccp;
106#endif
107#ifdef CONFIG_NETFILTER
108 struct netns_nf nf;
109 struct netns_xt xt;
110#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
111 struct netns_ct ct;
112#endif
113#if defined(CONFIG_NF_TABLES) || defined(CONFIG_NF_TABLES_MODULE)
114 struct netns_nftables nft;
115#endif
116#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
117 struct netns_nf_frag nf_frag;
118#endif
119 struct sock *nfnl;
120 struct sock *nfnl_stash;
121#if IS_ENABLED(CONFIG_NETFILTER_NETLINK_ACCT)
122 struct list_head nfnl_acct_list;
123#endif
124#if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
125 struct list_head nfct_timeout_list;
126#endif
127#endif
128#ifdef CONFIG_WEXT_CORE
129 struct sk_buff_head wext_nlevents;
130#endif
131 struct net_generic __rcu *gen;
132
133 /* Note : following structs are cache line aligned */
134#ifdef CONFIG_XFRM
135 struct netns_xfrm xfrm;
136#endif
137#if IS_ENABLED(CONFIG_IP_VS)
138 struct netns_ipvs *ipvs;
139#endif
140#if IS_ENABLED(CONFIG_MPLS)
141 struct netns_mpls mpls;
142#endif
143 struct sock *diag_nlsk;
144 atomic_t fnhe_genid;
145};
146
147#include <linux/seq_file_net.h>
148
149/* Init's network namespace */
150extern struct net init_net;
151
152#ifdef CONFIG_NET_NS
153struct net *copy_net_ns(unsigned long flags, struct user_namespace *user_ns,
154 struct net *old_net);
155
156#else /* CONFIG_NET_NS */
157#include <linux/sched.h>
158#include <linux/nsproxy.h>
159static inline struct net *copy_net_ns(unsigned long flags,
160 struct user_namespace *user_ns, struct net *old_net)
161{
162 if (flags & CLONE_NEWNET)
163 return ERR_PTR(-EINVAL);
164 return old_net;
165}
166#endif /* CONFIG_NET_NS */
167
168
169extern struct list_head net_namespace_list;
170
171struct net *get_net_ns_by_pid(pid_t pid);
172struct net *get_net_ns_by_fd(int pid);
173
174#ifdef CONFIG_SYSCTL
175void ipx_register_sysctl(void);
176void ipx_unregister_sysctl(void);
177#else
178#define ipx_register_sysctl()
179#define ipx_unregister_sysctl()
180#endif
181
182#ifdef CONFIG_NET_NS
183void __put_net(struct net *net);
184
185static inline struct net *get_net(struct net *net)
186{
187 atomic_inc(&net->count);
188 return net;
189}
190
191static inline struct net *maybe_get_net(struct net *net)
192{
193 /* Used when we know struct net exists but we
194 * aren't guaranteed a previous reference count
195 * exists. If the reference count is zero this
196 * function fails and returns NULL.
197 */
198 if (!atomic_inc_not_zero(&net->count))
199 net = NULL;
200 return net;
201}
202
203static inline void put_net(struct net *net)
204{
205 if (atomic_dec_and_test(&net->count))
206 __put_net(net);
207}
208
209static inline
210int net_eq(const struct net *net1, const struct net *net2)
211{
212 return net1 == net2;
213}
214
215void net_drop_ns(void *);
216
217#else
218
219static inline struct net *get_net(struct net *net)
220{
221 return net;
222}
223
224static inline void put_net(struct net *net)
225{
226}
227
228static inline struct net *maybe_get_net(struct net *net)
229{
230 return net;
231}
232
233static inline
234int net_eq(const struct net *net1, const struct net *net2)
235{
236 return 1;
237}
238
239#define net_drop_ns NULL
240#endif
241
242
243typedef struct {
244#ifdef CONFIG_NET_NS
245 struct net *net;
246#endif
247} possible_net_t;
248
249static inline void write_pnet(possible_net_t *pnet, struct net *net)
250{
251#ifdef CONFIG_NET_NS
252 pnet->net = net;
253#endif
254}
255
256static inline struct net *read_pnet(const possible_net_t *pnet)
257{
258#ifdef CONFIG_NET_NS
259 return pnet->net;
260#else
261 return &init_net;
262#endif
263}
264
265#define for_each_net(VAR) \
266 list_for_each_entry(VAR, &net_namespace_list, list)
267
268#define for_each_net_rcu(VAR) \
269 list_for_each_entry_rcu(VAR, &net_namespace_list, list)
270
271#ifdef CONFIG_NET_NS
272#define __net_init
273#define __net_exit
274#define __net_initdata
275#define __net_initconst
276#else
277#define __net_init __init
278#define __net_exit __exit_refok
279#define __net_initdata __initdata
280#define __net_initconst __initconst
281#endif
282
283int peernet2id_alloc(struct net *net, struct net *peer);
284int peernet2id(struct net *net, struct net *peer);
285bool peernet_has_id(struct net *net, struct net *peer);
286struct net *get_net_ns_by_id(struct net *net, int id);
287
288struct pernet_operations {
289 struct list_head list;
290 int (*init)(struct net *net);
291 void (*exit)(struct net *net);
292 void (*exit_batch)(struct list_head *net_exit_list);
293 int *id;
294 size_t size;
295};
296
297/*
298 * Use these carefully. If you implement a network device and it
299 * needs per network namespace operations use device pernet operations,
300 * otherwise use pernet subsys operations.
301 *
302 * Network interfaces need to be removed from a dying netns _before_
303 * subsys notifiers can be called, as most of the network code cleanup
304 * (which is done from subsys notifiers) runs with the assumption that
305 * dev_remove_pack has been called so no new packets will arrive during
306 * and after the cleanup functions have been called. dev_remove_pack
307 * is not per namespace so instead the guarantee of no more packets
308 * arriving in a network namespace is provided by ensuring that all
309 * network devices and all sockets have left the network namespace
310 * before the cleanup methods are called.
311 *
312 * For the longest time the ipv4 icmp code was registered as a pernet
313 * device which caused kernel oops, and panics during network
314 * namespace cleanup. So please don't get this wrong.
315 */
316int register_pernet_subsys(struct pernet_operations *);
317void unregister_pernet_subsys(struct pernet_operations *);
318int register_pernet_device(struct pernet_operations *);
319void unregister_pernet_device(struct pernet_operations *);
320
321struct ctl_table;
322struct ctl_table_header;
323
324#ifdef CONFIG_SYSCTL
325int net_sysctl_init(void);
326struct ctl_table_header *register_net_sysctl(struct net *net, const char *path,
327 struct ctl_table *table);
328void unregister_net_sysctl_table(struct ctl_table_header *header);
329#else
330static inline int net_sysctl_init(void) { return 0; }
331static inline struct ctl_table_header *register_net_sysctl(struct net *net,
332 const char *path, struct ctl_table *table)
333{
334 return NULL;
335}
336static inline void unregister_net_sysctl_table(struct ctl_table_header *header)
337{
338}
339#endif
340
341static inline int rt_genid_ipv4(struct net *net)
342{
343 return atomic_read(&net->ipv4.rt_genid);
344}
345
346static inline void rt_genid_bump_ipv4(struct net *net)
347{
348 atomic_inc(&net->ipv4.rt_genid);
349}
350
351extern void (*__fib6_flush_trees)(struct net *net);
352static inline void rt_genid_bump_ipv6(struct net *net)
353{
354 if (__fib6_flush_trees)
355 __fib6_flush_trees(net);
356}
357
358#if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
359static inline struct netns_ieee802154_lowpan *
360net_ieee802154_lowpan(struct net *net)
361{
362 return &net->ieee802154_lowpan;
363}
364#endif
365
366/* For callers who don't really care about whether it's IPv4 or IPv6 */
367static inline void rt_genid_bump_all(struct net *net)
368{
369 rt_genid_bump_ipv4(net);
370 rt_genid_bump_ipv6(net);
371}
372
373static inline int fnhe_genid(struct net *net)
374{
375 return atomic_read(&net->fnhe_genid);
376}
377
378static inline void fnhe_genid_bump(struct net *net)
379{
380 atomic_inc(&net->fnhe_genid);
381}
382
383#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#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
27#include <net/netns/conntrack.h>
28#endif
29#if IS_ENABLED(CONFIG_NF_FLOW_TABLE)
30#include <net/netns/flow_table.h>
31#endif
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>
45
46struct user_namespace;
47struct proc_dir_entry;
48struct net_device;
49struct sock;
50struct ctl_table_header;
51struct net_generic;
52struct uevent_sock;
53struct netns_ipvs;
54struct bpf_prog;
55
56
57#define NETDEV_HASHBITS 8
58#define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS)
59
60struct net {
61 /* First cache line can be often dirtied.
62 * Do not place here read-mostly fields.
63 */
64 refcount_t passive; /* To decide when the network
65 * namespace should be freed.
66 */
67 spinlock_t rules_mod_lock;
68
69 atomic_t dev_unreg_count;
70
71 unsigned int dev_base_seq; /* protected by rtnl_mutex */
72 int ifindex;
73
74 spinlock_t nsid_lock;
75 atomic_t fnhe_genid;
76
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).
83 */
84 struct llist_node cleanup_list; /* namespaces on death row */
85
86#ifdef CONFIG_KEYS
87 struct key_tag *key_domain; /* Key domain of operation tag */
88#endif
89 struct user_namespace *user_ns; /* Owning user namespace */
90 struct ucounts *ucounts;
91 struct idr netns_ids;
92
93 struct ns_common ns;
94 struct ref_tracker_dir refcnt_tracker;
95 struct ref_tracker_dir notrefcnt_tracker; /* tracker for objects not
96 * refcounted against netns
97 */
98 struct list_head dev_base_head;
99 struct proc_dir_entry *proc_net;
100 struct proc_dir_entry *proc_net_stat;
101
102#ifdef CONFIG_SYSCTL
103 struct ctl_table_set sysctls;
104#endif
105
106 struct sock *rtnl; /* rtnetlink socket */
107 struct sock *genl_sock;
108
109 struct uevent_sock *uevent_sock; /* uevent socket */
110
111 struct hlist_head *dev_name_head;
112 struct hlist_head *dev_index_head;
113 struct raw_notifier_head netdev_chain;
114
115 /* Note that @hash_mix can be read millions times per second,
116 * it is critical that it is on a read_mostly cache line.
117 */
118 u32 hash_mix;
119
120 struct net_device *loopback_dev; /* The loopback */
121
122 /* core fib_rules */
123 struct list_head rules_ops;
124
125 struct netns_core core;
126 struct netns_mib mib;
127 struct netns_packet packet;
128#if IS_ENABLED(CONFIG_UNIX)
129 struct netns_unix unx;
130#endif
131 struct netns_nexthop nexthop;
132 struct netns_ipv4 ipv4;
133#if IS_ENABLED(CONFIG_IPV6)
134 struct netns_ipv6 ipv6;
135#endif
136#if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
137 struct netns_ieee802154_lowpan ieee802154_lowpan;
138#endif
139#if defined(CONFIG_IP_SCTP) || defined(CONFIG_IP_SCTP_MODULE)
140 struct netns_sctp sctp;
141#endif
142#ifdef CONFIG_NETFILTER
143 struct netns_nf nf;
144#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
145 struct netns_ct ct;
146#endif
147#if defined(CONFIG_NF_TABLES) || defined(CONFIG_NF_TABLES_MODULE)
148 struct netns_nftables nft;
149#endif
150#if IS_ENABLED(CONFIG_NF_FLOW_TABLE)
151 struct netns_ft ft;
152#endif
153#endif
154#ifdef CONFIG_WEXT_CORE
155 struct sk_buff_head wext_nlevents;
156#endif
157 struct net_generic __rcu *gen;
158
159 /* Used to store attached BPF programs */
160 struct netns_bpf bpf;
161
162 /* Note : following structs are cache line aligned */
163#ifdef CONFIG_XFRM
164 struct netns_xfrm xfrm;
165#endif
166
167 u64 net_cookie; /* written once */
168
169#if IS_ENABLED(CONFIG_IP_VS)
170 struct netns_ipvs *ipvs;
171#endif
172#if IS_ENABLED(CONFIG_MPLS)
173 struct netns_mpls mpls;
174#endif
175#if IS_ENABLED(CONFIG_CAN)
176 struct netns_can can;
177#endif
178#ifdef CONFIG_XDP_SOCKETS
179 struct netns_xdp xdp;
180#endif
181#if IS_ENABLED(CONFIG_MCTP)
182 struct netns_mctp mctp;
183#endif
184#if IS_ENABLED(CONFIG_CRYPTO_USER)
185 struct sock *crypto_nlsk;
186#endif
187 struct sock *diag_nlsk;
188#if IS_ENABLED(CONFIG_SMC)
189 struct netns_smc smc;
190#endif
191} __randomize_layout;
192
193#include <linux/seq_file_net.h>
194
195/* Init's network namespace */
196extern struct net init_net;
197
198#ifdef CONFIG_NET_NS
199struct net *copy_net_ns(unsigned long flags, struct user_namespace *user_ns,
200 struct net *old_net);
201
202void net_ns_get_ownership(const struct net *net, kuid_t *uid, kgid_t *gid);
203
204void net_ns_barrier(void);
205
206struct ns_common *get_net_ns(struct ns_common *ns);
207struct net *get_net_ns_by_fd(int fd);
208#else /* CONFIG_NET_NS */
209#include <linux/sched.h>
210#include <linux/nsproxy.h>
211static inline struct net *copy_net_ns(unsigned long flags,
212 struct user_namespace *user_ns, struct net *old_net)
213{
214 if (flags & CLONE_NEWNET)
215 return ERR_PTR(-EINVAL);
216 return old_net;
217}
218
219static inline void net_ns_get_ownership(const struct net *net,
220 kuid_t *uid, kgid_t *gid)
221{
222 *uid = GLOBAL_ROOT_UID;
223 *gid = GLOBAL_ROOT_GID;
224}
225
226static inline void net_ns_barrier(void) {}
227
228static inline struct ns_common *get_net_ns(struct ns_common *ns)
229{
230 return ERR_PTR(-EINVAL);
231}
232
233static inline struct net *get_net_ns_by_fd(int fd)
234{
235 return ERR_PTR(-EINVAL);
236}
237#endif /* CONFIG_NET_NS */
238
239
240extern struct list_head net_namespace_list;
241
242struct net *get_net_ns_by_pid(pid_t pid);
243
244#ifdef CONFIG_SYSCTL
245void ipx_register_sysctl(void);
246void ipx_unregister_sysctl(void);
247#else
248#define ipx_register_sysctl()
249#define ipx_unregister_sysctl()
250#endif
251
252#ifdef CONFIG_NET_NS
253void __put_net(struct net *net);
254
255/* Try using get_net_track() instead */
256static inline struct net *get_net(struct net *net)
257{
258 refcount_inc(&net->ns.count);
259 return net;
260}
261
262static inline struct net *maybe_get_net(struct net *net)
263{
264 /* Used when we know struct net exists but we
265 * aren't guaranteed a previous reference count
266 * exists. If the reference count is zero this
267 * function fails and returns NULL.
268 */
269 if (!refcount_inc_not_zero(&net->ns.count))
270 net = NULL;
271 return net;
272}
273
274/* Try using put_net_track() instead */
275static inline void put_net(struct net *net)
276{
277 if (refcount_dec_and_test(&net->ns.count))
278 __put_net(net);
279}
280
281static inline
282int net_eq(const struct net *net1, const struct net *net2)
283{
284 return net1 == net2;
285}
286
287static inline int check_net(const struct net *net)
288{
289 return refcount_read(&net->ns.count) != 0;
290}
291
292void net_drop_ns(void *);
293
294#else
295
296static inline struct net *get_net(struct net *net)
297{
298 return net;
299}
300
301static inline void put_net(struct net *net)
302{
303}
304
305static inline struct net *maybe_get_net(struct net *net)
306{
307 return net;
308}
309
310static inline
311int net_eq(const struct net *net1, const struct net *net2)
312{
313 return 1;
314}
315
316static inline int check_net(const struct net *net)
317{
318 return 1;
319}
320
321#define net_drop_ns NULL
322#endif
323
324
325static inline void __netns_tracker_alloc(struct net *net,
326 netns_tracker *tracker,
327 bool refcounted,
328 gfp_t gfp)
329{
330#ifdef CONFIG_NET_NS_REFCNT_TRACKER
331 ref_tracker_alloc(refcounted ? &net->refcnt_tracker :
332 &net->notrefcnt_tracker,
333 tracker, gfp);
334#endif
335}
336
337static inline void netns_tracker_alloc(struct net *net, netns_tracker *tracker,
338 gfp_t gfp)
339{
340 __netns_tracker_alloc(net, tracker, true, gfp);
341}
342
343static inline void __netns_tracker_free(struct net *net,
344 netns_tracker *tracker,
345 bool refcounted)
346{
347#ifdef CONFIG_NET_NS_REFCNT_TRACKER
348 ref_tracker_free(refcounted ? &net->refcnt_tracker :
349 &net->notrefcnt_tracker, tracker);
350#endif
351}
352
353static inline struct net *get_net_track(struct net *net,
354 netns_tracker *tracker, gfp_t gfp)
355{
356 get_net(net);
357 netns_tracker_alloc(net, tracker, gfp);
358 return net;
359}
360
361static inline void put_net_track(struct net *net, netns_tracker *tracker)
362{
363 __netns_tracker_free(net, tracker, true);
364 put_net(net);
365}
366
367typedef struct {
368#ifdef CONFIG_NET_NS
369 struct net *net;
370#endif
371} possible_net_t;
372
373static inline void write_pnet(possible_net_t *pnet, struct net *net)
374{
375#ifdef CONFIG_NET_NS
376 pnet->net = net;
377#endif
378}
379
380static inline struct net *read_pnet(const possible_net_t *pnet)
381{
382#ifdef CONFIG_NET_NS
383 return pnet->net;
384#else
385 return &init_net;
386#endif
387}
388
389/* Protected by net_rwsem */
390#define for_each_net(VAR) \
391 list_for_each_entry(VAR, &net_namespace_list, list)
392#define for_each_net_continue_reverse(VAR) \
393 list_for_each_entry_continue_reverse(VAR, &net_namespace_list, list)
394#define for_each_net_rcu(VAR) \
395 list_for_each_entry_rcu(VAR, &net_namespace_list, list)
396
397#ifdef CONFIG_NET_NS
398#define __net_init
399#define __net_exit
400#define __net_initdata
401#define __net_initconst
402#else
403#define __net_init __init
404#define __net_exit __ref
405#define __net_initdata __initdata
406#define __net_initconst __initconst
407#endif
408
409int peernet2id_alloc(struct net *net, struct net *peer, gfp_t gfp);
410int peernet2id(const struct net *net, struct net *peer);
411bool peernet_has_id(const struct net *net, struct net *peer);
412struct net *get_net_ns_by_id(const struct net *net, int id);
413
414struct pernet_operations {
415 struct list_head list;
416 /*
417 * Below methods are called without any exclusive locks.
418 * More than one net may be constructed and destructed
419 * in parallel on several cpus. Every pernet_operations
420 * have to keep in mind all other pernet_operations and
421 * to introduce a locking, if they share common resources.
422 *
423 * The only time they are called with exclusive lock is
424 * from register_pernet_subsys(), unregister_pernet_subsys()
425 * register_pernet_device() and unregister_pernet_device().
426 *
427 * Exit methods using blocking RCU primitives, such as
428 * synchronize_rcu(), should be implemented via exit_batch.
429 * Then, destruction of a group of net requires single
430 * synchronize_rcu() related to these pernet_operations,
431 * instead of separate synchronize_rcu() for every net.
432 * Please, avoid synchronize_rcu() at all, where it's possible.
433 *
434 * Note that a combination of pre_exit() and exit() can
435 * be used, since a synchronize_rcu() is guaranteed between
436 * the calls.
437 */
438 int (*init)(struct net *net);
439 void (*pre_exit)(struct net *net);
440 void (*exit)(struct net *net);
441 void (*exit_batch)(struct list_head *net_exit_list);
442 unsigned int *id;
443 size_t size;
444};
445
446/*
447 * Use these carefully. If you implement a network device and it
448 * needs per network namespace operations use device pernet operations,
449 * otherwise use pernet subsys operations.
450 *
451 * Network interfaces need to be removed from a dying netns _before_
452 * subsys notifiers can be called, as most of the network code cleanup
453 * (which is done from subsys notifiers) runs with the assumption that
454 * dev_remove_pack has been called so no new packets will arrive during
455 * and after the cleanup functions have been called. dev_remove_pack
456 * is not per namespace so instead the guarantee of no more packets
457 * arriving in a network namespace is provided by ensuring that all
458 * network devices and all sockets have left the network namespace
459 * before the cleanup methods are called.
460 *
461 * For the longest time the ipv4 icmp code was registered as a pernet
462 * device which caused kernel oops, and panics during network
463 * namespace cleanup. So please don't get this wrong.
464 */
465int register_pernet_subsys(struct pernet_operations *);
466void unregister_pernet_subsys(struct pernet_operations *);
467int register_pernet_device(struct pernet_operations *);
468void unregister_pernet_device(struct pernet_operations *);
469
470struct ctl_table;
471
472#ifdef CONFIG_SYSCTL
473int net_sysctl_init(void);
474struct ctl_table_header *register_net_sysctl(struct net *net, const char *path,
475 struct ctl_table *table);
476void unregister_net_sysctl_table(struct ctl_table_header *header);
477#else
478static inline int net_sysctl_init(void) { return 0; }
479static inline struct ctl_table_header *register_net_sysctl(struct net *net,
480 const char *path, struct ctl_table *table)
481{
482 return NULL;
483}
484static inline void unregister_net_sysctl_table(struct ctl_table_header *header)
485{
486}
487#endif
488
489static inline int rt_genid_ipv4(const struct net *net)
490{
491 return atomic_read(&net->ipv4.rt_genid);
492}
493
494#if IS_ENABLED(CONFIG_IPV6)
495static inline int rt_genid_ipv6(const struct net *net)
496{
497 return atomic_read(&net->ipv6.fib6_sernum);
498}
499#endif
500
501static inline void rt_genid_bump_ipv4(struct net *net)
502{
503 atomic_inc(&net->ipv4.rt_genid);
504}
505
506extern void (*__fib6_flush_trees)(struct net *net);
507static inline void rt_genid_bump_ipv6(struct net *net)
508{
509 if (__fib6_flush_trees)
510 __fib6_flush_trees(net);
511}
512
513#if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
514static inline struct netns_ieee802154_lowpan *
515net_ieee802154_lowpan(struct net *net)
516{
517 return &net->ieee802154_lowpan;
518}
519#endif
520
521/* For callers who don't really care about whether it's IPv4 or IPv6 */
522static inline void rt_genid_bump_all(struct net *net)
523{
524 rt_genid_bump_ipv4(net);
525 rt_genid_bump_ipv6(net);
526}
527
528static inline int fnhe_genid(const struct net *net)
529{
530 return atomic_read(&net->fnhe_genid);
531}
532
533static inline void fnhe_genid_bump(struct net *net)
534{
535 atomic_inc(&net->fnhe_genid);
536}
537
538#ifdef CONFIG_NET
539void net_ns_init(void);
540#else
541static inline void net_ns_init(void) {}
542#endif
543
544#endif /* __NET_NET_NAMESPACE_H */