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v5.4
  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/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>
 30#endif
 
 
 
 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>
 
 
 39
 40struct user_namespace;
 41struct proc_dir_entry;
 42struct net_device;
 43struct sock;
 44struct ctl_table_header;
 45struct net_generic;
 46struct uevent_sock;
 47struct netns_ipvs;
 48struct bpf_prog;
 49
 50
 51#define NETDEV_HASHBITS    8
 52#define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS)
 53
 54struct net {
 55	/* First cache line can be often dirtied.
 56	 * Do not place here read-mostly fields.
 57	 */
 58	refcount_t		passive;	/* To decide when the network
 59						 * namespace should be freed.
 60						 */
 61	refcount_t		count;		/* To decided when the network
 62						 *  namespace should be shut down.
 63						 */
 64	spinlock_t		rules_mod_lock;
 65
 66	unsigned int		dev_unreg_count;
 67
 68	unsigned int		dev_base_seq;	/* protected by rtnl_mutex */
 69	int			ifindex;
 70
 71	spinlock_t		nsid_lock;
 72	atomic_t		fnhe_genid;
 73
 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).
 80						 */
 81	struct llist_node	cleanup_list;	/* namespaces on death row */
 82
 83#ifdef CONFIG_KEYS
 84	struct key_tag		*key_domain;	/* Key domain of operation tag */
 85#endif
 86	struct user_namespace   *user_ns;	/* Owning user namespace */
 87	struct ucounts		*ucounts;
 88	struct idr		netns_ids;
 89
 90	struct ns_common	ns;
 91
 
 
 
 92	struct list_head 	dev_base_head;
 93	struct proc_dir_entry 	*proc_net;
 94	struct proc_dir_entry 	*proc_net_stat;
 95
 96#ifdef CONFIG_SYSCTL
 97	struct ctl_table_set	sysctls;
 98#endif
 99
100	struct sock 		*rtnl;			/* rtnetlink socket */
101	struct sock		*genl_sock;
102
103	struct uevent_sock	*uevent_sock;		/* uevent socket */
104
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.
109	 */
110	u32			hash_mix;
111
112	struct net_device       *loopback_dev;          /* The loopback */
113
114	/* core fib_rules */
115	struct list_head	rules_ops;
116
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;
125#endif
126#if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
127	struct netns_ieee802154_lowpan	ieee802154_lowpan;
128#endif
129#if defined(CONFIG_IP_SCTP) || defined(CONFIG_IP_SCTP_MODULE)
130	struct netns_sctp	sctp;
131#endif
132#if defined(CONFIG_IP_DCCP) || defined(CONFIG_IP_DCCP_MODULE)
133	struct netns_dccp	dccp;
134#endif
135#ifdef CONFIG_NETFILTER
136	struct netns_nf		nf;
137	struct netns_xt		xt;
138#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
139	struct netns_ct		ct;
140#endif
141#if defined(CONFIG_NF_TABLES) || defined(CONFIG_NF_TABLES_MODULE)
142	struct netns_nftables	nft;
143#endif
144#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
145	struct netns_nf_frag	nf_frag;
146	struct ctl_table_header *nf_frag_frags_hdr;
147#endif
148	struct sock		*nfnl;
149	struct sock		*nfnl_stash;
150#if IS_ENABLED(CONFIG_NETFILTER_NETLINK_ACCT)
151	struct list_head        nfnl_acct_list;
152#endif
153#if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
154	struct list_head	nfct_timeout_list;
155#endif
156#endif
157#ifdef CONFIG_WEXT_CORE
158	struct sk_buff_head	wext_nlevents;
159#endif
160	struct net_generic __rcu	*gen;
161
162	struct bpf_prog __rcu	*flow_dissector_prog;
 
163
164	/* Note : following structs are cache line aligned */
165#ifdef CONFIG_XFRM
166	struct netns_xfrm	xfrm;
167#endif
 
 
 
168#if IS_ENABLED(CONFIG_IP_VS)
169	struct netns_ipvs	*ipvs;
170#endif
171#if IS_ENABLED(CONFIG_MPLS)
172	struct netns_mpls	mpls;
173#endif
174#if IS_ENABLED(CONFIG_CAN)
175	struct netns_can	can;
176#endif
177#ifdef CONFIG_XDP_SOCKETS
178	struct netns_xdp	xdp;
179#endif
 
 
 
180#if IS_ENABLED(CONFIG_CRYPTO_USER)
181	struct sock		*crypto_nlsk;
182#endif
183	struct sock		*diag_nlsk;
 
 
 
184} __randomize_layout;
185
186#include <linux/seq_file_net.h>
187
188/* Init's network namespace */
189extern struct net init_net;
190
191#ifdef CONFIG_NET_NS
192struct net *copy_net_ns(unsigned long flags, struct user_namespace *user_ns,
193			struct net *old_net);
194
195void net_ns_get_ownership(const struct net *net, kuid_t *uid, kgid_t *gid);
196
197void net_ns_barrier(void);
 
 
 
198#else /* CONFIG_NET_NS */
199#include <linux/sched.h>
200#include <linux/nsproxy.h>
201static inline struct net *copy_net_ns(unsigned long flags,
202	struct user_namespace *user_ns, struct net *old_net)
203{
204	if (flags & CLONE_NEWNET)
205		return ERR_PTR(-EINVAL);
206	return old_net;
207}
208
209static inline void net_ns_get_ownership(const struct net *net,
210					kuid_t *uid, kgid_t *gid)
211{
212	*uid = GLOBAL_ROOT_UID;
213	*gid = GLOBAL_ROOT_GID;
214}
215
216static inline void net_ns_barrier(void) {}
 
 
 
 
 
 
 
 
 
 
217#endif /* CONFIG_NET_NS */
218
219
220extern struct list_head net_namespace_list;
221
222struct net *get_net_ns_by_pid(pid_t pid);
223struct net *get_net_ns_by_fd(int fd);
224
225#ifdef CONFIG_SYSCTL
226void ipx_register_sysctl(void);
227void ipx_unregister_sysctl(void);
228#else
229#define ipx_register_sysctl()
230#define ipx_unregister_sysctl()
231#endif
232
233#ifdef CONFIG_NET_NS
234void __put_net(struct net *net);
235
 
236static inline struct net *get_net(struct net *net)
237{
238	refcount_inc(&net->count);
239	return net;
240}
241
242static inline struct net *maybe_get_net(struct net *net)
243{
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.
248	 */
249	if (!refcount_inc_not_zero(&net->count))
250		net = NULL;
251	return net;
252}
253
 
254static inline void put_net(struct net *net)
255{
256	if (refcount_dec_and_test(&net->count))
257		__put_net(net);
258}
259
260static inline
261int net_eq(const struct net *net1, const struct net *net2)
262{
263	return net1 == net2;
264}
265
266static inline int check_net(const struct net *net)
267{
268	return refcount_read(&net->count) != 0;
269}
270
271void net_drop_ns(void *);
272
273#else
274
275static inline struct net *get_net(struct net *net)
276{
277	return net;
278}
279
280static inline void put_net(struct net *net)
281{
282}
283
284static inline struct net *maybe_get_net(struct net *net)
285{
286	return net;
287}
288
289static inline
290int net_eq(const struct net *net1, const struct net *net2)
291{
292	return 1;
293}
294
295static inline int check_net(const struct net *net)
296{
297	return 1;
298}
299
300#define net_drop_ns NULL
301#endif
302
303
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
304typedef struct {
305#ifdef CONFIG_NET_NS
306	struct net *net;
307#endif
308} possible_net_t;
309
310static inline void write_pnet(possible_net_t *pnet, struct net *net)
311{
312#ifdef CONFIG_NET_NS
313	pnet->net = net;
314#endif
315}
316
317static inline struct net *read_pnet(const possible_net_t *pnet)
318{
319#ifdef CONFIG_NET_NS
320	return pnet->net;
 
 
 
 
 
 
 
 
 
321#else
322	return &init_net;
323#endif
324}
325
326/* Protected by net_rwsem */
327#define for_each_net(VAR)				\
328	list_for_each_entry(VAR, &net_namespace_list, list)
329
 
330#define for_each_net_rcu(VAR)				\
331	list_for_each_entry_rcu(VAR, &net_namespace_list, list)
332
333#ifdef CONFIG_NET_NS
334#define __net_init
335#define __net_exit
336#define __net_initdata
337#define __net_initconst
338#else
339#define __net_init	__init
340#define __net_exit	__ref
341#define __net_initdata	__initdata
342#define __net_initconst	__initconst
343#endif
344
345int peernet2id_alloc(struct net *net, struct net *peer, gfp_t gfp);
346int peernet2id(struct net *net, struct net *peer);
347bool peernet_has_id(struct net *net, struct net *peer);
348struct net *get_net_ns_by_id(struct net *net, int id);
349
350struct pernet_operations {
351	struct list_head list;
352	/*
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.
358	 *
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().
362	 *
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.
369	 *
370	 * Note that a combination of pre_exit() and exit() can
371	 * be used, since a synchronize_rcu() is guaranteed between
372	 * the calls.
373	 */
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);
378	unsigned int *id;
379	size_t size;
380};
381
382/*
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.
386 *
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.
396 *
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.
400 */
401int register_pernet_subsys(struct pernet_operations *);
402void unregister_pernet_subsys(struct pernet_operations *);
403int register_pernet_device(struct pernet_operations *);
404void unregister_pernet_device(struct pernet_operations *);
405
406struct ctl_table;
407struct ctl_table_header;
408
 
 
409#ifdef CONFIG_SYSCTL
410int net_sysctl_init(void);
411struct ctl_table_header *register_net_sysctl(struct net *net, const char *path,
412					     struct ctl_table *table);
413void unregister_net_sysctl_table(struct ctl_table_header *header);
414#else
415static inline int net_sysctl_init(void) { return 0; }
416static inline struct ctl_table_header *register_net_sysctl(struct net *net,
417	const char *path, struct ctl_table *table)
418{
419	return NULL;
420}
421static inline void unregister_net_sysctl_table(struct ctl_table_header *header)
422{
423}
424#endif
425
426static inline int rt_genid_ipv4(struct net *net)
427{
428	return atomic_read(&net->ipv4.rt_genid);
429}
430
 
 
 
 
 
 
 
431static inline void rt_genid_bump_ipv4(struct net *net)
432{
433	atomic_inc(&net->ipv4.rt_genid);
434}
435
436extern void (*__fib6_flush_trees)(struct net *net);
437static inline void rt_genid_bump_ipv6(struct net *net)
438{
439	if (__fib6_flush_trees)
440		__fib6_flush_trees(net);
441}
442
443#if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
444static inline struct netns_ieee802154_lowpan *
445net_ieee802154_lowpan(struct net *net)
446{
447	return &net->ieee802154_lowpan;
448}
449#endif
450
451/* For callers who don't really care about whether it's IPv4 or IPv6 */
452static inline void rt_genid_bump_all(struct net *net)
453{
454	rt_genid_bump_ipv4(net);
455	rt_genid_bump_ipv6(net);
456}
457
458static inline int fnhe_genid(struct net *net)
459{
460	return atomic_read(&net->fnhe_genid);
461}
462
463static inline void fnhe_genid_bump(struct net *net)
464{
465	atomic_inc(&net->fnhe_genid);
466}
 
 
 
 
 
 
467
468#endif /* __NET_NET_NAMESPACE_H */
v6.8
  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#include <linux/xarray.h>
 46
 47struct user_namespace;
 48struct proc_dir_entry;
 49struct net_device;
 50struct sock;
 51struct ctl_table_header;
 52struct net_generic;
 53struct uevent_sock;
 54struct netns_ipvs;
 55struct bpf_prog;
 56
 57
 58#define NETDEV_HASHBITS    8
 59#define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS)
 60
 61struct net {
 62	/* First cache line can be often dirtied.
 63	 * Do not place here read-mostly fields.
 64	 */
 65	refcount_t		passive;	/* To decide when the network
 66						 * namespace should be freed.
 67						 */
 
 
 
 68	spinlock_t		rules_mod_lock;
 69
 70	atomic_t		dev_unreg_count;
 71
 72	unsigned int		dev_base_seq;	/* protected by rtnl_mutex */
 73	u32			ifindex;
 74
 75	spinlock_t		nsid_lock;
 76	atomic_t		fnhe_genid;
 77
 78	struct list_head	list;		/* list of network namespaces */
 79	struct list_head	exit_list;	/* To linked to call pernet exit
 80						 * methods on dead net (
 81						 * pernet_ops_rwsem read locked),
 82						 * or to unregister pernet ops
 83						 * (pernet_ops_rwsem write locked).
 84						 */
 85	struct llist_node	cleanup_list;	/* namespaces on death row */
 86
 87#ifdef CONFIG_KEYS
 88	struct key_tag		*key_domain;	/* Key domain of operation tag */
 89#endif
 90	struct user_namespace   *user_ns;	/* Owning user namespace */
 91	struct ucounts		*ucounts;
 92	struct idr		netns_ids;
 93
 94	struct ns_common	ns;
 95	struct ref_tracker_dir  refcnt_tracker;
 96	struct ref_tracker_dir  notrefcnt_tracker; /* tracker for objects not
 97						    * refcounted against netns
 98						    */
 99	struct list_head 	dev_base_head;
100	struct proc_dir_entry 	*proc_net;
101	struct proc_dir_entry 	*proc_net_stat;
102
103#ifdef CONFIG_SYSCTL
104	struct ctl_table_set	sysctls;
105#endif
106
107	struct sock 		*rtnl;			/* rtnetlink socket */
108	struct sock		*genl_sock;
109
110	struct uevent_sock	*uevent_sock;		/* uevent socket */
111
112	struct hlist_head 	*dev_name_head;
113	struct hlist_head	*dev_index_head;
114	struct xarray		dev_by_index;
115	struct raw_notifier_head	netdev_chain;
116
117	/* Note that @hash_mix can be read millions times per second,
118	 * it is critical that it is on a read_mostly cache line.
119	 */
120	u32			hash_mix;
121
122	struct net_device       *loopback_dev;          /* The loopback */
123
124	/* core fib_rules */
125	struct list_head	rules_ops;
126
127	struct netns_core	core;
128	struct netns_mib	mib;
129	struct netns_packet	packet;
130#if IS_ENABLED(CONFIG_UNIX)
131	struct netns_unix	unx;
132#endif
133	struct netns_nexthop	nexthop;
134	struct netns_ipv4	ipv4;
135#if IS_ENABLED(CONFIG_IPV6)
136	struct netns_ipv6	ipv6;
137#endif
138#if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
139	struct netns_ieee802154_lowpan	ieee802154_lowpan;
140#endif
141#if defined(CONFIG_IP_SCTP) || defined(CONFIG_IP_SCTP_MODULE)
142	struct netns_sctp	sctp;
143#endif
 
 
 
144#ifdef CONFIG_NETFILTER
145	struct netns_nf		nf;
 
146#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
147	struct netns_ct		ct;
148#endif
149#if defined(CONFIG_NF_TABLES) || defined(CONFIG_NF_TABLES_MODULE)
150	struct netns_nftables	nft;
151#endif
152#if IS_ENABLED(CONFIG_NF_FLOW_TABLE)
153	struct netns_ft ft;
 
 
 
 
 
 
 
 
 
154#endif
155#endif
156#ifdef CONFIG_WEXT_CORE
157	struct sk_buff_head	wext_nlevents;
158#endif
159	struct net_generic __rcu	*gen;
160
161	/* Used to store attached BPF programs */
162	struct netns_bpf	bpf;
163
164	/* Note : following structs are cache line aligned */
165#ifdef CONFIG_XFRM
166	struct netns_xfrm	xfrm;
167#endif
168
169	u64			net_cookie; /* written once */
170
171#if IS_ENABLED(CONFIG_IP_VS)
172	struct netns_ipvs	*ipvs;
173#endif
174#if IS_ENABLED(CONFIG_MPLS)
175	struct netns_mpls	mpls;
176#endif
177#if IS_ENABLED(CONFIG_CAN)
178	struct netns_can	can;
179#endif
180#ifdef CONFIG_XDP_SOCKETS
181	struct netns_xdp	xdp;
182#endif
183#if IS_ENABLED(CONFIG_MCTP)
184	struct netns_mctp	mctp;
185#endif
186#if IS_ENABLED(CONFIG_CRYPTO_USER)
187	struct sock		*crypto_nlsk;
188#endif
189	struct sock		*diag_nlsk;
190#if IS_ENABLED(CONFIG_SMC)
191	struct netns_smc	smc;
192#endif
193} __randomize_layout;
194
195#include <linux/seq_file_net.h>
196
197/* Init's network namespace */
198extern struct net init_net;
199
200#ifdef CONFIG_NET_NS
201struct net *copy_net_ns(unsigned long flags, struct user_namespace *user_ns,
202			struct net *old_net);
203
204void net_ns_get_ownership(const struct net *net, kuid_t *uid, kgid_t *gid);
205
206void net_ns_barrier(void);
207
208struct ns_common *get_net_ns(struct ns_common *ns);
209struct net *get_net_ns_by_fd(int fd);
210#else /* CONFIG_NET_NS */
211#include <linux/sched.h>
212#include <linux/nsproxy.h>
213static inline struct net *copy_net_ns(unsigned long flags,
214	struct user_namespace *user_ns, struct net *old_net)
215{
216	if (flags & CLONE_NEWNET)
217		return ERR_PTR(-EINVAL);
218	return old_net;
219}
220
221static inline void net_ns_get_ownership(const struct net *net,
222					kuid_t *uid, kgid_t *gid)
223{
224	*uid = GLOBAL_ROOT_UID;
225	*gid = GLOBAL_ROOT_GID;
226}
227
228static inline void net_ns_barrier(void) {}
229
230static inline struct ns_common *get_net_ns(struct ns_common *ns)
231{
232	return ERR_PTR(-EINVAL);
233}
234
235static inline struct net *get_net_ns_by_fd(int fd)
236{
237	return ERR_PTR(-EINVAL);
238}
239#endif /* CONFIG_NET_NS */
240
241
242extern struct list_head net_namespace_list;
243
244struct net *get_net_ns_by_pid(pid_t pid);
 
245
246#ifdef CONFIG_SYSCTL
247void ipx_register_sysctl(void);
248void ipx_unregister_sysctl(void);
249#else
250#define ipx_register_sysctl()
251#define ipx_unregister_sysctl()
252#endif
253
254#ifdef CONFIG_NET_NS
255void __put_net(struct net *net);
256
257/* Try using get_net_track() instead */
258static inline struct net *get_net(struct net *net)
259{
260	refcount_inc(&net->ns.count);
261	return net;
262}
263
264static inline struct net *maybe_get_net(struct net *net)
265{
266	/* Used when we know struct net exists but we
267	 * aren't guaranteed a previous reference count
268	 * exists.  If the reference count is zero this
269	 * function fails and returns NULL.
270	 */
271	if (!refcount_inc_not_zero(&net->ns.count))
272		net = NULL;
273	return net;
274}
275
276/* Try using put_net_track() instead */
277static inline void put_net(struct net *net)
278{
279	if (refcount_dec_and_test(&net->ns.count))
280		__put_net(net);
281}
282
283static inline
284int net_eq(const struct net *net1, const struct net *net2)
285{
286	return net1 == net2;
287}
288
289static inline int check_net(const struct net *net)
290{
291	return refcount_read(&net->ns.count) != 0;
292}
293
294void net_drop_ns(void *);
295
296#else
297
298static inline struct net *get_net(struct net *net)
299{
300	return net;
301}
302
303static inline void put_net(struct net *net)
304{
305}
306
307static inline struct net *maybe_get_net(struct net *net)
308{
309	return net;
310}
311
312static inline
313int net_eq(const struct net *net1, const struct net *net2)
314{
315	return 1;
316}
317
318static inline int check_net(const struct net *net)
319{
320	return 1;
321}
322
323#define net_drop_ns NULL
324#endif
325
326
327static inline void __netns_tracker_alloc(struct net *net,
328					 netns_tracker *tracker,
329					 bool refcounted,
330					 gfp_t gfp)
331{
332#ifdef CONFIG_NET_NS_REFCNT_TRACKER
333	ref_tracker_alloc(refcounted ? &net->refcnt_tracker :
334				       &net->notrefcnt_tracker,
335			  tracker, gfp);
336#endif
337}
338
339static inline void netns_tracker_alloc(struct net *net, netns_tracker *tracker,
340				       gfp_t gfp)
341{
342	__netns_tracker_alloc(net, tracker, true, gfp);
343}
344
345static inline void __netns_tracker_free(struct net *net,
346					netns_tracker *tracker,
347					bool refcounted)
348{
349#ifdef CONFIG_NET_NS_REFCNT_TRACKER
350       ref_tracker_free(refcounted ? &net->refcnt_tracker :
351				     &net->notrefcnt_tracker, tracker);
352#endif
353}
354
355static inline struct net *get_net_track(struct net *net,
356					netns_tracker *tracker, gfp_t gfp)
357{
358	get_net(net);
359	netns_tracker_alloc(net, tracker, gfp);
360	return net;
361}
362
363static inline void put_net_track(struct net *net, netns_tracker *tracker)
364{
365	__netns_tracker_free(net, tracker, true);
366	put_net(net);
367}
368
369typedef struct {
370#ifdef CONFIG_NET_NS
371	struct net __rcu *net;
372#endif
373} possible_net_t;
374
375static inline void write_pnet(possible_net_t *pnet, struct net *net)
376{
377#ifdef CONFIG_NET_NS
378	rcu_assign_pointer(pnet->net, net);
379#endif
380}
381
382static inline struct net *read_pnet(const possible_net_t *pnet)
383{
384#ifdef CONFIG_NET_NS
385	return rcu_dereference_protected(pnet->net, true);
386#else
387	return &init_net;
388#endif
389}
390
391static inline struct net *read_pnet_rcu(possible_net_t *pnet)
392{
393#ifdef CONFIG_NET_NS
394	return rcu_dereference(pnet->net);
395#else
396	return &init_net;
397#endif
398}
399
400/* Protected by net_rwsem */
401#define for_each_net(VAR)				\
402	list_for_each_entry(VAR, &net_namespace_list, list)
403#define for_each_net_continue_reverse(VAR)		\
404	list_for_each_entry_continue_reverse(VAR, &net_namespace_list, list)
405#define for_each_net_rcu(VAR)				\
406	list_for_each_entry_rcu(VAR, &net_namespace_list, list)
407
408#ifdef CONFIG_NET_NS
409#define __net_init
410#define __net_exit
411#define __net_initdata
412#define __net_initconst
413#else
414#define __net_init	__init
415#define __net_exit	__ref
416#define __net_initdata	__initdata
417#define __net_initconst	__initconst
418#endif
419
420int peernet2id_alloc(struct net *net, struct net *peer, gfp_t gfp);
421int peernet2id(const struct net *net, struct net *peer);
422bool peernet_has_id(const struct net *net, struct net *peer);
423struct net *get_net_ns_by_id(const struct net *net, int id);
424
425struct pernet_operations {
426	struct list_head list;
427	/*
428	 * Below methods are called without any exclusive locks.
429	 * More than one net may be constructed and destructed
430	 * in parallel on several cpus. Every pernet_operations
431	 * have to keep in mind all other pernet_operations and
432	 * to introduce a locking, if they share common resources.
433	 *
434	 * The only time they are called with exclusive lock is
435	 * from register_pernet_subsys(), unregister_pernet_subsys()
436	 * register_pernet_device() and unregister_pernet_device().
437	 *
438	 * Exit methods using blocking RCU primitives, such as
439	 * synchronize_rcu(), should be implemented via exit_batch.
440	 * Then, destruction of a group of net requires single
441	 * synchronize_rcu() related to these pernet_operations,
442	 * instead of separate synchronize_rcu() for every net.
443	 * Please, avoid synchronize_rcu() at all, where it's possible.
444	 *
445	 * Note that a combination of pre_exit() and exit() can
446	 * be used, since a synchronize_rcu() is guaranteed between
447	 * the calls.
448	 */
449	int (*init)(struct net *net);
450	void (*pre_exit)(struct net *net);
451	void (*exit)(struct net *net);
452	void (*exit_batch)(struct list_head *net_exit_list);
453	unsigned int *id;
454	size_t size;
455};
456
457/*
458 * Use these carefully.  If you implement a network device and it
459 * needs per network namespace operations use device pernet operations,
460 * otherwise use pernet subsys operations.
461 *
462 * Network interfaces need to be removed from a dying netns _before_
463 * subsys notifiers can be called, as most of the network code cleanup
464 * (which is done from subsys notifiers) runs with the assumption that
465 * dev_remove_pack has been called so no new packets will arrive during
466 * and after the cleanup functions have been called.  dev_remove_pack
467 * is not per namespace so instead the guarantee of no more packets
468 * arriving in a network namespace is provided by ensuring that all
469 * network devices and all sockets have left the network namespace
470 * before the cleanup methods are called.
471 *
472 * For the longest time the ipv4 icmp code was registered as a pernet
473 * device which caused kernel oops, and panics during network
474 * namespace cleanup.   So please don't get this wrong.
475 */
476int register_pernet_subsys(struct pernet_operations *);
477void unregister_pernet_subsys(struct pernet_operations *);
478int register_pernet_device(struct pernet_operations *);
479void unregister_pernet_device(struct pernet_operations *);
480
481struct ctl_table;
 
482
483#define register_net_sysctl(net, path, table)	\
484	register_net_sysctl_sz(net, path, table, ARRAY_SIZE(table))
485#ifdef CONFIG_SYSCTL
486int net_sysctl_init(void);
487struct ctl_table_header *register_net_sysctl_sz(struct net *net, const char *path,
488					     struct ctl_table *table, size_t table_size);
489void unregister_net_sysctl_table(struct ctl_table_header *header);
490#else
491static inline int net_sysctl_init(void) { return 0; }
492static inline struct ctl_table_header *register_net_sysctl_sz(struct net *net,
493	const char *path, struct ctl_table *table, size_t table_size)
494{
495	return NULL;
496}
497static inline void unregister_net_sysctl_table(struct ctl_table_header *header)
498{
499}
500#endif
501
502static inline int rt_genid_ipv4(const struct net *net)
503{
504	return atomic_read(&net->ipv4.rt_genid);
505}
506
507#if IS_ENABLED(CONFIG_IPV6)
508static inline int rt_genid_ipv6(const struct net *net)
509{
510	return atomic_read(&net->ipv6.fib6_sernum);
511}
512#endif
513
514static inline void rt_genid_bump_ipv4(struct net *net)
515{
516	atomic_inc(&net->ipv4.rt_genid);
517}
518
519extern void (*__fib6_flush_trees)(struct net *net);
520static inline void rt_genid_bump_ipv6(struct net *net)
521{
522	if (__fib6_flush_trees)
523		__fib6_flush_trees(net);
524}
525
526#if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
527static inline struct netns_ieee802154_lowpan *
528net_ieee802154_lowpan(struct net *net)
529{
530	return &net->ieee802154_lowpan;
531}
532#endif
533
534/* For callers who don't really care about whether it's IPv4 or IPv6 */
535static inline void rt_genid_bump_all(struct net *net)
536{
537	rt_genid_bump_ipv4(net);
538	rt_genid_bump_ipv6(net);
539}
540
541static inline int fnhe_genid(const struct net *net)
542{
543	return atomic_read(&net->fnhe_genid);
544}
545
546static inline void fnhe_genid_bump(struct net *net)
547{
548	atomic_inc(&net->fnhe_genid);
549}
550
551#ifdef CONFIG_NET
552void net_ns_init(void);
553#else
554static inline void net_ns_init(void) {}
555#endif
556
557#endif /* __NET_NET_NAMESPACE_H */