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
32struct user_namespace;
33struct proc_dir_entry;
34struct net_device;
35struct sock;
36struct ctl_table_header;
37struct net_generic;
38struct sock;
39struct netns_ipvs;
40
41
42#define NETDEV_HASHBITS    8
43#define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS)
44
45struct net {
46	atomic_t		passive;	/* To decided when the network
47						 * namespace should be freed.
48						 */
49	atomic_t		count;		/* To decided when the network
50						 *  namespace should be shut down.
51						 */
52	spinlock_t		rules_mod_lock;
53
54	atomic64_t		cookie_gen;
55
56	struct list_head	list;		/* list of network namespaces */
57	struct list_head	cleanup_list;	/* namespaces on death row */
58	struct list_head	exit_list;	/* Use only net_mutex */
59
60	struct user_namespace   *user_ns;	/* Owning user namespace */
61	struct idr		netns_ids;
62
63	struct ns_common	ns;
64
65	struct proc_dir_entry 	*proc_net;
66	struct proc_dir_entry 	*proc_net_stat;
67
68#ifdef CONFIG_SYSCTL
69	struct ctl_table_set	sysctls;
70#endif
71
72	struct sock 		*rtnl;			/* rtnetlink socket */
73	struct sock		*genl_sock;
74
75	struct list_head 	dev_base_head;
76	struct hlist_head 	*dev_name_head;
77	struct hlist_head	*dev_index_head;
78	unsigned int		dev_base_seq;	/* protected by rtnl_mutex */
79	int			ifindex;
80	unsigned int		dev_unreg_count;
81
82	/* core fib_rules */
83	struct list_head	rules_ops;
84
85
86	struct net_device       *loopback_dev;          /* The loopback */
87	struct netns_core	core;
88	struct netns_mib	mib;
89	struct netns_packet	packet;
90	struct netns_unix	unx;
91	struct netns_ipv4	ipv4;
92#if IS_ENABLED(CONFIG_IPV6)
93	struct netns_ipv6	ipv6;
94#endif
95#if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
96	struct netns_ieee802154_lowpan	ieee802154_lowpan;
97#endif
98#if defined(CONFIG_IP_SCTP) || defined(CONFIG_IP_SCTP_MODULE)
99	struct netns_sctp	sctp;
100#endif
101#if defined(CONFIG_IP_DCCP) || defined(CONFIG_IP_DCCP_MODULE)
102	struct netns_dccp	dccp;
103#endif
104#ifdef CONFIG_NETFILTER
105	struct netns_nf		nf;
106	struct netns_xt		xt;
107#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
108	struct netns_ct		ct;
109#endif
110#if defined(CONFIG_NF_TABLES) || defined(CONFIG_NF_TABLES_MODULE)
111	struct netns_nftables	nft;
112#endif
113#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
114	struct netns_nf_frag	nf_frag;
115#endif
116	struct sock		*nfnl;
117	struct sock		*nfnl_stash;
118#endif
119#ifdef CONFIG_WEXT_CORE
120	struct sk_buff_head	wext_nlevents;
121#endif
122	struct net_generic __rcu	*gen;
123
124	/* Note : following structs are cache line aligned */
125#ifdef CONFIG_XFRM
126	struct netns_xfrm	xfrm;
127#endif
128#if IS_ENABLED(CONFIG_IP_VS)
129	struct netns_ipvs	*ipvs;
130#endif
131#if IS_ENABLED(CONFIG_MPLS)
132	struct netns_mpls	mpls;
133#endif
134	struct sock		*diag_nlsk;
135	atomic_t		fnhe_genid;
136};
137
138#include <linux/seq_file_net.h>
139
140/* Init's network namespace */
141extern struct net init_net;
142
143#ifdef CONFIG_NET_NS
144struct net *copy_net_ns(unsigned long flags, struct user_namespace *user_ns,
145			struct net *old_net);
146
147#else /* CONFIG_NET_NS */
148#include <linux/sched.h>
149#include <linux/nsproxy.h>
150static inline struct net *copy_net_ns(unsigned long flags,
151	struct user_namespace *user_ns, struct net *old_net)
152{
153	if (flags & CLONE_NEWNET)
154		return ERR_PTR(-EINVAL);
155	return old_net;
156}
157#endif /* CONFIG_NET_NS */
158
159
160extern struct list_head net_namespace_list;
161
162struct net *get_net_ns_by_pid(pid_t pid);
163struct net *get_net_ns_by_fd(int pid);
164
165#ifdef CONFIG_SYSCTL
166void ipx_register_sysctl(void);
167void ipx_unregister_sysctl(void);
168#else
169#define ipx_register_sysctl()
170#define ipx_unregister_sysctl()
171#endif
172
173#ifdef CONFIG_NET_NS
174void __put_net(struct net *net);
175
176static inline struct net *get_net(struct net *net)
177{
178	atomic_inc(&net->count);
179	return net;
180}
181
182static inline struct net *maybe_get_net(struct net *net)
183{
184	/* Used when we know struct net exists but we
185	 * aren't guaranteed a previous reference count
186	 * exists.  If the reference count is zero this
187	 * function fails and returns NULL.
188	 */
189	if (!atomic_inc_not_zero(&net->count))
190		net = NULL;
191	return net;
192}
193
194static inline void put_net(struct net *net)
195{
196	if (atomic_dec_and_test(&net->count))
197		__put_net(net);
198}
199
200static inline
201int net_eq(const struct net *net1, const struct net *net2)
202{
203	return net1 == net2;
204}
205
206void net_drop_ns(void *);
207
208#else
209
210static inline struct net *get_net(struct net *net)
211{
212	return net;
213}
214
215static inline void put_net(struct net *net)
216{
217}
218
219static inline struct net *maybe_get_net(struct net *net)
220{
221	return net;
222}
223
224static inline
225int net_eq(const struct net *net1, const struct net *net2)
226{
227	return 1;
228}
229
230#define net_drop_ns NULL
231#endif
232
233
234typedef struct {
235#ifdef CONFIG_NET_NS
236	struct net *net;
237#endif
238} possible_net_t;
239
240static inline void write_pnet(possible_net_t *pnet, struct net *net)
241{
242#ifdef CONFIG_NET_NS
243	pnet->net = net;
244#endif
245}
246
247static inline struct net *read_pnet(const possible_net_t *pnet)
248{
249#ifdef CONFIG_NET_NS
250	return pnet->net;
251#else
252	return &init_net;
253#endif
254}
255
256#define for_each_net(VAR)				\
257	list_for_each_entry(VAR, &net_namespace_list, list)
258
259#define for_each_net_rcu(VAR)				\
260	list_for_each_entry_rcu(VAR, &net_namespace_list, list)
261
262#ifdef CONFIG_NET_NS
263#define __net_init
264#define __net_exit
265#define __net_initdata
266#define __net_initconst
267#else
268#define __net_init	__init
269#define __net_exit	__exit_refok
270#define __net_initdata	__initdata
271#define __net_initconst	__initconst
272#endif
273
274int peernet2id(struct net *net, struct net *peer);
275struct net *get_net_ns_by_id(struct net *net, int id);
276
277struct pernet_operations {
278	struct list_head list;
279	int (*init)(struct net *net);
280	void (*exit)(struct net *net);
281	void (*exit_batch)(struct list_head *net_exit_list);
282	int *id;
283	size_t size;
284};
285
286/*
287 * Use these carefully.  If you implement a network device and it
288 * needs per network namespace operations use device pernet operations,
289 * otherwise use pernet subsys operations.
290 *
291 * Network interfaces need to be removed from a dying netns _before_
292 * subsys notifiers can be called, as most of the network code cleanup
293 * (which is done from subsys notifiers) runs with the assumption that
294 * dev_remove_pack has been called so no new packets will arrive during
295 * and after the cleanup functions have been called.  dev_remove_pack
296 * is not per namespace so instead the guarantee of no more packets
297 * arriving in a network namespace is provided by ensuring that all
298 * network devices and all sockets have left the network namespace
299 * before the cleanup methods are called.
300 *
301 * For the longest time the ipv4 icmp code was registered as a pernet
302 * device which caused kernel oops, and panics during network
303 * namespace cleanup.   So please don't get this wrong.
304 */
305int register_pernet_subsys(struct pernet_operations *);
306void unregister_pernet_subsys(struct pernet_operations *);
307int register_pernet_device(struct pernet_operations *);
308void unregister_pernet_device(struct pernet_operations *);
309
310struct ctl_table;
311struct ctl_table_header;
312
313#ifdef CONFIG_SYSCTL
314int net_sysctl_init(void);
315struct ctl_table_header *register_net_sysctl(struct net *net, const char *path,
316					     struct ctl_table *table);
317void unregister_net_sysctl_table(struct ctl_table_header *header);
318#else
319static inline int net_sysctl_init(void) { return 0; }
320static inline struct ctl_table_header *register_net_sysctl(struct net *net,
321	const char *path, struct ctl_table *table)
322{
323	return NULL;
324}
325static inline void unregister_net_sysctl_table(struct ctl_table_header *header)
326{
327}
328#endif
329
330static inline int rt_genid_ipv4(struct net *net)
331{
332	return atomic_read(&net->ipv4.rt_genid);
333}
334
335static inline void rt_genid_bump_ipv4(struct net *net)
336{
337	atomic_inc(&net->ipv4.rt_genid);
338}
339
340extern void (*__fib6_flush_trees)(struct net *net);
341static inline void rt_genid_bump_ipv6(struct net *net)
342{
343	if (__fib6_flush_trees)
344		__fib6_flush_trees(net);
345}
346
347#if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
348static inline struct netns_ieee802154_lowpan *
349net_ieee802154_lowpan(struct net *net)
350{
351	return &net->ieee802154_lowpan;
352}
353#endif
354
355/* For callers who don't really care about whether it's IPv4 or IPv6 */
356static inline void rt_genid_bump_all(struct net *net)
357{
358	rt_genid_bump_ipv4(net);
359	rt_genid_bump_ipv6(net);
360}
361
362static inline int fnhe_genid(struct net *net)
363{
364	return atomic_read(&net->fnhe_genid);
365}
366
367static inline void fnhe_genid_bump(struct net *net)
368{
369	atomic_inc(&net->fnhe_genid);
370}
371
372#endif /* __NET_NET_NAMESPACE_H */
373