xref: /openbmc/linux/include/net/net_namespace.h (revision 9cfc5c90)
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 
34 struct user_namespace;
35 struct proc_dir_entry;
36 struct net_device;
37 struct sock;
38 struct ctl_table_header;
39 struct net_generic;
40 struct sock;
41 struct netns_ipvs;
42 
43 
44 #define NETDEV_HASHBITS    8
45 #define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS)
46 
47 struct 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 #endif
125 #ifdef CONFIG_WEXT_CORE
126 	struct sk_buff_head	wext_nlevents;
127 #endif
128 	struct net_generic __rcu	*gen;
129 
130 	/* Note : following structs are cache line aligned */
131 #ifdef CONFIG_XFRM
132 	struct netns_xfrm	xfrm;
133 #endif
134 #if IS_ENABLED(CONFIG_IP_VS)
135 	struct netns_ipvs	*ipvs;
136 #endif
137 #if IS_ENABLED(CONFIG_MPLS)
138 	struct netns_mpls	mpls;
139 #endif
140 	struct sock		*diag_nlsk;
141 	atomic_t		fnhe_genid;
142 };
143 
144 #include <linux/seq_file_net.h>
145 
146 /* Init's network namespace */
147 extern struct net init_net;
148 
149 #ifdef CONFIG_NET_NS
150 struct net *copy_net_ns(unsigned long flags, struct user_namespace *user_ns,
151 			struct net *old_net);
152 
153 #else /* CONFIG_NET_NS */
154 #include <linux/sched.h>
155 #include <linux/nsproxy.h>
156 static inline struct net *copy_net_ns(unsigned long flags,
157 	struct user_namespace *user_ns, struct net *old_net)
158 {
159 	if (flags & CLONE_NEWNET)
160 		return ERR_PTR(-EINVAL);
161 	return old_net;
162 }
163 #endif /* CONFIG_NET_NS */
164 
165 
166 extern struct list_head net_namespace_list;
167 
168 struct net *get_net_ns_by_pid(pid_t pid);
169 struct net *get_net_ns_by_fd(int pid);
170 
171 #ifdef CONFIG_SYSCTL
172 void ipx_register_sysctl(void);
173 void ipx_unregister_sysctl(void);
174 #else
175 #define ipx_register_sysctl()
176 #define ipx_unregister_sysctl()
177 #endif
178 
179 #ifdef CONFIG_NET_NS
180 void __put_net(struct net *net);
181 
182 static inline struct net *get_net(struct net *net)
183 {
184 	atomic_inc(&net->count);
185 	return net;
186 }
187 
188 static inline struct net *maybe_get_net(struct net *net)
189 {
190 	/* Used when we know struct net exists but we
191 	 * aren't guaranteed a previous reference count
192 	 * exists.  If the reference count is zero this
193 	 * function fails and returns NULL.
194 	 */
195 	if (!atomic_inc_not_zero(&net->count))
196 		net = NULL;
197 	return net;
198 }
199 
200 static inline void put_net(struct net *net)
201 {
202 	if (atomic_dec_and_test(&net->count))
203 		__put_net(net);
204 }
205 
206 static inline
207 int net_eq(const struct net *net1, const struct net *net2)
208 {
209 	return net1 == net2;
210 }
211 
212 void net_drop_ns(void *);
213 
214 #else
215 
216 static inline struct net *get_net(struct net *net)
217 {
218 	return net;
219 }
220 
221 static inline void put_net(struct net *net)
222 {
223 }
224 
225 static inline struct net *maybe_get_net(struct net *net)
226 {
227 	return net;
228 }
229 
230 static inline
231 int net_eq(const struct net *net1, const struct net *net2)
232 {
233 	return 1;
234 }
235 
236 #define net_drop_ns NULL
237 #endif
238 
239 
240 typedef struct {
241 #ifdef CONFIG_NET_NS
242 	struct net *net;
243 #endif
244 } possible_net_t;
245 
246 static inline void write_pnet(possible_net_t *pnet, struct net *net)
247 {
248 #ifdef CONFIG_NET_NS
249 	pnet->net = net;
250 #endif
251 }
252 
253 static inline struct net *read_pnet(const possible_net_t *pnet)
254 {
255 #ifdef CONFIG_NET_NS
256 	return pnet->net;
257 #else
258 	return &init_net;
259 #endif
260 }
261 
262 #define for_each_net(VAR)				\
263 	list_for_each_entry(VAR, &net_namespace_list, list)
264 
265 #define for_each_net_rcu(VAR)				\
266 	list_for_each_entry_rcu(VAR, &net_namespace_list, list)
267 
268 #ifdef CONFIG_NET_NS
269 #define __net_init
270 #define __net_exit
271 #define __net_initdata
272 #define __net_initconst
273 #else
274 #define __net_init	__init
275 #define __net_exit	__exit_refok
276 #define __net_initdata	__initdata
277 #define __net_initconst	__initconst
278 #endif
279 
280 int peernet2id_alloc(struct net *net, struct net *peer);
281 int peernet2id(struct net *net, struct net *peer);
282 bool peernet_has_id(struct net *net, struct net *peer);
283 struct net *get_net_ns_by_id(struct net *net, int id);
284 
285 struct pernet_operations {
286 	struct list_head list;
287 	int (*init)(struct net *net);
288 	void (*exit)(struct net *net);
289 	void (*exit_batch)(struct list_head *net_exit_list);
290 	int *id;
291 	size_t size;
292 };
293 
294 /*
295  * Use these carefully.  If you implement a network device and it
296  * needs per network namespace operations use device pernet operations,
297  * otherwise use pernet subsys operations.
298  *
299  * Network interfaces need to be removed from a dying netns _before_
300  * subsys notifiers can be called, as most of the network code cleanup
301  * (which is done from subsys notifiers) runs with the assumption that
302  * dev_remove_pack has been called so no new packets will arrive during
303  * and after the cleanup functions have been called.  dev_remove_pack
304  * is not per namespace so instead the guarantee of no more packets
305  * arriving in a network namespace is provided by ensuring that all
306  * network devices and all sockets have left the network namespace
307  * before the cleanup methods are called.
308  *
309  * For the longest time the ipv4 icmp code was registered as a pernet
310  * device which caused kernel oops, and panics during network
311  * namespace cleanup.   So please don't get this wrong.
312  */
313 int register_pernet_subsys(struct pernet_operations *);
314 void unregister_pernet_subsys(struct pernet_operations *);
315 int register_pernet_device(struct pernet_operations *);
316 void unregister_pernet_device(struct pernet_operations *);
317 
318 struct ctl_table;
319 struct ctl_table_header;
320 
321 #ifdef CONFIG_SYSCTL
322 int net_sysctl_init(void);
323 struct ctl_table_header *register_net_sysctl(struct net *net, const char *path,
324 					     struct ctl_table *table);
325 void unregister_net_sysctl_table(struct ctl_table_header *header);
326 #else
327 static inline int net_sysctl_init(void) { return 0; }
328 static inline struct ctl_table_header *register_net_sysctl(struct net *net,
329 	const char *path, struct ctl_table *table)
330 {
331 	return NULL;
332 }
333 static inline void unregister_net_sysctl_table(struct ctl_table_header *header)
334 {
335 }
336 #endif
337 
338 static inline int rt_genid_ipv4(struct net *net)
339 {
340 	return atomic_read(&net->ipv4.rt_genid);
341 }
342 
343 static inline void rt_genid_bump_ipv4(struct net *net)
344 {
345 	atomic_inc(&net->ipv4.rt_genid);
346 }
347 
348 extern void (*__fib6_flush_trees)(struct net *net);
349 static inline void rt_genid_bump_ipv6(struct net *net)
350 {
351 	if (__fib6_flush_trees)
352 		__fib6_flush_trees(net);
353 }
354 
355 #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
356 static inline struct netns_ieee802154_lowpan *
357 net_ieee802154_lowpan(struct net *net)
358 {
359 	return &net->ieee802154_lowpan;
360 }
361 #endif
362 
363 /* For callers who don't really care about whether it's IPv4 or IPv6 */
364 static inline void rt_genid_bump_all(struct net *net)
365 {
366 	rt_genid_bump_ipv4(net);
367 	rt_genid_bump_ipv6(net);
368 }
369 
370 static inline int fnhe_genid(struct net *net)
371 {
372 	return atomic_read(&net->fnhe_genid);
373 }
374 
375 static inline void fnhe_genid_bump(struct net *net)
376 {
377 	atomic_inc(&net->fnhe_genid);
378 }
379 
380 #endif /* __NET_NET_NAMESPACE_H */
381