xref: /openbmc/linux/include/net/net_namespace.h (revision a03a8dbe20eff6d57aae3147577bf84b52aba4e6)
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 
32 struct user_namespace;
33 struct proc_dir_entry;
34 struct net_device;
35 struct sock;
36 struct ctl_table_header;
37 struct net_generic;
38 struct sock;
39 struct netns_ipvs;
40 
41 
42 #define NETDEV_HASHBITS    8
43 #define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS)
44 
45 struct 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 #ifdef NETNS_REFCNT_DEBUG
53 	atomic_t		use_count;	/* To track references we
54 						 * destroy on demand
55 						 */
56 #endif
57 	spinlock_t		rules_mod_lock;
58 
59 	struct list_head	list;		/* list of network namespaces */
60 	struct list_head	cleanup_list;	/* namespaces on death row */
61 	struct list_head	exit_list;	/* Use only net_mutex */
62 
63 	struct user_namespace   *user_ns;	/* Owning user namespace */
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 #endif
122 #ifdef CONFIG_WEXT_CORE
123 	struct sk_buff_head	wext_nlevents;
124 #endif
125 	struct net_generic __rcu	*gen;
126 
127 	/* Note : following structs are cache line aligned */
128 #ifdef CONFIG_XFRM
129 	struct netns_xfrm	xfrm;
130 #endif
131 #if IS_ENABLED(CONFIG_IP_VS)
132 	struct netns_ipvs	*ipvs;
133 #endif
134 #if IS_ENABLED(CONFIG_MPLS)
135 	struct netns_mpls	mpls;
136 #endif
137 	struct sock		*diag_nlsk;
138 	atomic_t		fnhe_genid;
139 };
140 
141 #include <linux/seq_file_net.h>
142 
143 /* Init's network namespace */
144 extern struct net init_net;
145 
146 #ifdef CONFIG_NET_NS
147 struct net *copy_net_ns(unsigned long flags, struct user_namespace *user_ns,
148 			struct net *old_net);
149 
150 #else /* CONFIG_NET_NS */
151 #include <linux/sched.h>
152 #include <linux/nsproxy.h>
153 static inline struct net *copy_net_ns(unsigned long flags,
154 	struct user_namespace *user_ns, struct net *old_net)
155 {
156 	if (flags & CLONE_NEWNET)
157 		return ERR_PTR(-EINVAL);
158 	return old_net;
159 }
160 #endif /* CONFIG_NET_NS */
161 
162 
163 extern struct list_head net_namespace_list;
164 
165 struct net *get_net_ns_by_pid(pid_t pid);
166 struct net *get_net_ns_by_fd(int pid);
167 
168 #ifdef CONFIG_SYSCTL
169 void ipx_register_sysctl(void);
170 void ipx_unregister_sysctl(void);
171 #else
172 #define ipx_register_sysctl()
173 #define ipx_unregister_sysctl()
174 #endif
175 
176 #ifdef CONFIG_NET_NS
177 void __put_net(struct net *net);
178 
179 static inline struct net *get_net(struct net *net)
180 {
181 	atomic_inc(&net->count);
182 	return net;
183 }
184 
185 static inline struct net *maybe_get_net(struct net *net)
186 {
187 	/* Used when we know struct net exists but we
188 	 * aren't guaranteed a previous reference count
189 	 * exists.  If the reference count is zero this
190 	 * function fails and returns NULL.
191 	 */
192 	if (!atomic_inc_not_zero(&net->count))
193 		net = NULL;
194 	return net;
195 }
196 
197 static inline void put_net(struct net *net)
198 {
199 	if (atomic_dec_and_test(&net->count))
200 		__put_net(net);
201 }
202 
203 static inline
204 int net_eq(const struct net *net1, const struct net *net2)
205 {
206 	return net1 == net2;
207 }
208 
209 void net_drop_ns(void *);
210 
211 #else
212 
213 static inline struct net *get_net(struct net *net)
214 {
215 	return net;
216 }
217 
218 static inline void put_net(struct net *net)
219 {
220 }
221 
222 static inline struct net *maybe_get_net(struct net *net)
223 {
224 	return net;
225 }
226 
227 static inline
228 int net_eq(const struct net *net1, const struct net *net2)
229 {
230 	return 1;
231 }
232 
233 #define net_drop_ns NULL
234 #endif
235 
236 
237 #ifdef NETNS_REFCNT_DEBUG
238 static inline struct net *hold_net(struct net *net)
239 {
240 	if (net)
241 		atomic_inc(&net->use_count);
242 	return net;
243 }
244 
245 static inline void release_net(struct net *net)
246 {
247 	if (net)
248 		atomic_dec(&net->use_count);
249 }
250 #else
251 static inline struct net *hold_net(struct net *net)
252 {
253 	return net;
254 }
255 
256 static inline void release_net(struct net *net)
257 {
258 }
259 #endif
260 
261 #ifdef CONFIG_NET_NS
262 
263 static inline void write_pnet(struct net **pnet, struct net *net)
264 {
265 	*pnet = net;
266 }
267 
268 static inline struct net *read_pnet(struct net * const *pnet)
269 {
270 	return *pnet;
271 }
272 
273 #else
274 
275 #define write_pnet(pnet, net)	do { (void)(net);} while (0)
276 #define read_pnet(pnet)		(&init_net)
277 
278 #endif
279 
280 #define for_each_net(VAR)				\
281 	list_for_each_entry(VAR, &net_namespace_list, list)
282 
283 #define for_each_net_rcu(VAR)				\
284 	list_for_each_entry_rcu(VAR, &net_namespace_list, list)
285 
286 #ifdef CONFIG_NET_NS
287 #define __net_init
288 #define __net_exit
289 #define __net_initdata
290 #define __net_initconst
291 #else
292 #define __net_init	__init
293 #define __net_exit	__exit_refok
294 #define __net_initdata	__initdata
295 #define __net_initconst	__initconst
296 #endif
297 
298 int peernet2id(struct net *net, struct net *peer);
299 struct net *get_net_ns_by_id(struct net *net, int id);
300 
301 struct pernet_operations {
302 	struct list_head list;
303 	int (*init)(struct net *net);
304 	void (*exit)(struct net *net);
305 	void (*exit_batch)(struct list_head *net_exit_list);
306 	int *id;
307 	size_t size;
308 };
309 
310 /*
311  * Use these carefully.  If you implement a network device and it
312  * needs per network namespace operations use device pernet operations,
313  * otherwise use pernet subsys operations.
314  *
315  * Network interfaces need to be removed from a dying netns _before_
316  * subsys notifiers can be called, as most of the network code cleanup
317  * (which is done from subsys notifiers) runs with the assumption that
318  * dev_remove_pack has been called so no new packets will arrive during
319  * and after the cleanup functions have been called.  dev_remove_pack
320  * is not per namespace so instead the guarantee of no more packets
321  * arriving in a network namespace is provided by ensuring that all
322  * network devices and all sockets have left the network namespace
323  * before the cleanup methods are called.
324  *
325  * For the longest time the ipv4 icmp code was registered as a pernet
326  * device which caused kernel oops, and panics during network
327  * namespace cleanup.   So please don't get this wrong.
328  */
329 int register_pernet_subsys(struct pernet_operations *);
330 void unregister_pernet_subsys(struct pernet_operations *);
331 int register_pernet_device(struct pernet_operations *);
332 void unregister_pernet_device(struct pernet_operations *);
333 
334 struct ctl_table;
335 struct ctl_table_header;
336 
337 #ifdef CONFIG_SYSCTL
338 int net_sysctl_init(void);
339 struct ctl_table_header *register_net_sysctl(struct net *net, const char *path,
340 					     struct ctl_table *table);
341 void unregister_net_sysctl_table(struct ctl_table_header *header);
342 #else
343 static inline int net_sysctl_init(void) { return 0; }
344 static inline struct ctl_table_header *register_net_sysctl(struct net *net,
345 	const char *path, struct ctl_table *table)
346 {
347 	return NULL;
348 }
349 static inline void unregister_net_sysctl_table(struct ctl_table_header *header)
350 {
351 }
352 #endif
353 
354 static inline int rt_genid_ipv4(struct net *net)
355 {
356 	return atomic_read(&net->ipv4.rt_genid);
357 }
358 
359 static inline void rt_genid_bump_ipv4(struct net *net)
360 {
361 	atomic_inc(&net->ipv4.rt_genid);
362 }
363 
364 extern void (*__fib6_flush_trees)(struct net *net);
365 static inline void rt_genid_bump_ipv6(struct net *net)
366 {
367 	if (__fib6_flush_trees)
368 		__fib6_flush_trees(net);
369 }
370 
371 #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
372 static inline struct netns_ieee802154_lowpan *
373 net_ieee802154_lowpan(struct net *net)
374 {
375 	return &net->ieee802154_lowpan;
376 }
377 #endif
378 
379 /* For callers who don't really care about whether it's IPv4 or IPv6 */
380 static inline void rt_genid_bump_all(struct net *net)
381 {
382 	rt_genid_bump_ipv4(net);
383 	rt_genid_bump_ipv6(net);
384 }
385 
386 static inline int fnhe_genid(struct net *net)
387 {
388 	return atomic_read(&net->fnhe_genid);
389 }
390 
391 static inline void fnhe_genid_bump(struct net *net)
392 {
393 	atomic_inc(&net->fnhe_genid);
394 }
395 
396 #endif /* __NET_NET_NAMESPACE_H */
397