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v5.14.15
  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 */
v6.2
  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 */