xref: /openbmc/linux/include/net/net_namespace.h (revision 7866cc57b51c1e118e5d78d1a8f721f378eec5c4)
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 <net/netns/can.h>
31 #include <linux/ns_common.h>
32 #include <linux/idr.h>
33 #include <linux/skbuff.h>
34 
35 struct user_namespace;
36 struct proc_dir_entry;
37 struct net_device;
38 struct sock;
39 struct ctl_table_header;
40 struct net_generic;
41 struct sock;
42 struct netns_ipvs;
43 
44 
45 #define NETDEV_HASHBITS    8
46 #define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS)
47 
48 struct net {
49 	atomic_t		passive;	/* To decided when the network
50 						 * namespace should be freed.
51 						 */
52 	atomic_t		count;		/* To decided when the network
53 						 *  namespace should be shut down.
54 						 */
55 	spinlock_t		rules_mod_lock;
56 
57 	atomic64_t		cookie_gen;
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 ucounts		*ucounts;
65 	spinlock_t		nsid_lock;
66 	struct idr		netns_ids;
67 
68 	struct ns_common	ns;
69 
70 	struct proc_dir_entry 	*proc_net;
71 	struct proc_dir_entry 	*proc_net_stat;
72 
73 #ifdef CONFIG_SYSCTL
74 	struct ctl_table_set	sysctls;
75 #endif
76 
77 	struct sock 		*rtnl;			/* rtnetlink socket */
78 	struct sock		*genl_sock;
79 
80 	struct list_head 	dev_base_head;
81 	struct hlist_head 	*dev_name_head;
82 	struct hlist_head	*dev_index_head;
83 	unsigned int		dev_base_seq;	/* protected by rtnl_mutex */
84 	int			ifindex;
85 	unsigned int		dev_unreg_count;
86 
87 	/* core fib_rules */
88 	struct list_head	rules_ops;
89 
90 
91 	struct net_device       *loopback_dev;          /* The loopback */
92 	struct netns_core	core;
93 	struct netns_mib	mib;
94 	struct netns_packet	packet;
95 	struct netns_unix	unx;
96 	struct netns_ipv4	ipv4;
97 #if IS_ENABLED(CONFIG_IPV6)
98 	struct netns_ipv6	ipv6;
99 #endif
100 #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
101 	struct netns_ieee802154_lowpan	ieee802154_lowpan;
102 #endif
103 #if defined(CONFIG_IP_SCTP) || defined(CONFIG_IP_SCTP_MODULE)
104 	struct netns_sctp	sctp;
105 #endif
106 #if defined(CONFIG_IP_DCCP) || defined(CONFIG_IP_DCCP_MODULE)
107 	struct netns_dccp	dccp;
108 #endif
109 #ifdef CONFIG_NETFILTER
110 	struct netns_nf		nf;
111 	struct netns_xt		xt;
112 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
113 	struct netns_ct		ct;
114 #endif
115 #if defined(CONFIG_NF_TABLES) || defined(CONFIG_NF_TABLES_MODULE)
116 	struct netns_nftables	nft;
117 #endif
118 #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
119 	struct netns_nf_frag	nf_frag;
120 #endif
121 	struct sock		*nfnl;
122 	struct sock		*nfnl_stash;
123 #if IS_ENABLED(CONFIG_NETFILTER_NETLINK_ACCT)
124 	struct list_head        nfnl_acct_list;
125 #endif
126 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
127 	struct list_head	nfct_timeout_list;
128 #endif
129 #endif
130 #ifdef CONFIG_WEXT_CORE
131 	struct sk_buff_head	wext_nlevents;
132 #endif
133 	struct net_generic __rcu	*gen;
134 
135 	/* Note : following structs are cache line aligned */
136 #ifdef CONFIG_XFRM
137 	struct netns_xfrm	xfrm;
138 #endif
139 #if IS_ENABLED(CONFIG_IP_VS)
140 	struct netns_ipvs	*ipvs;
141 #endif
142 #if IS_ENABLED(CONFIG_MPLS)
143 	struct netns_mpls	mpls;
144 #endif
145 #if IS_ENABLED(CONFIG_CAN)
146 	struct netns_can	can;
147 #endif
148 	struct sock		*diag_nlsk;
149 	atomic_t		fnhe_genid;
150 };
151 
152 #include <linux/seq_file_net.h>
153 
154 /* Init's network namespace */
155 extern struct net init_net;
156 
157 #ifdef CONFIG_NET_NS
158 struct net *copy_net_ns(unsigned long flags, struct user_namespace *user_ns,
159 			struct net *old_net);
160 
161 void net_ns_barrier(void);
162 #else /* CONFIG_NET_NS */
163 #include <linux/sched.h>
164 #include <linux/nsproxy.h>
165 static inline struct net *copy_net_ns(unsigned long flags,
166 	struct user_namespace *user_ns, struct net *old_net)
167 {
168 	if (flags & CLONE_NEWNET)
169 		return ERR_PTR(-EINVAL);
170 	return old_net;
171 }
172 
173 static inline void net_ns_barrier(void) {}
174 #endif /* CONFIG_NET_NS */
175 
176 
177 extern struct list_head net_namespace_list;
178 
179 struct net *get_net_ns_by_pid(pid_t pid);
180 struct net *get_net_ns_by_fd(int fd);
181 
182 #ifdef CONFIG_SYSCTL
183 void ipx_register_sysctl(void);
184 void ipx_unregister_sysctl(void);
185 #else
186 #define ipx_register_sysctl()
187 #define ipx_unregister_sysctl()
188 #endif
189 
190 #ifdef CONFIG_NET_NS
191 void __put_net(struct net *net);
192 
193 static inline struct net *get_net(struct net *net)
194 {
195 	atomic_inc(&net->count);
196 	return net;
197 }
198 
199 static inline struct net *maybe_get_net(struct net *net)
200 {
201 	/* Used when we know struct net exists but we
202 	 * aren't guaranteed a previous reference count
203 	 * exists.  If the reference count is zero this
204 	 * function fails and returns NULL.
205 	 */
206 	if (!atomic_inc_not_zero(&net->count))
207 		net = NULL;
208 	return net;
209 }
210 
211 static inline void put_net(struct net *net)
212 {
213 	if (atomic_dec_and_test(&net->count))
214 		__put_net(net);
215 }
216 
217 static inline
218 int net_eq(const struct net *net1, const struct net *net2)
219 {
220 	return net1 == net2;
221 }
222 
223 void net_drop_ns(void *);
224 
225 #else
226 
227 static inline struct net *get_net(struct net *net)
228 {
229 	return net;
230 }
231 
232 static inline void put_net(struct net *net)
233 {
234 }
235 
236 static inline struct net *maybe_get_net(struct net *net)
237 {
238 	return net;
239 }
240 
241 static inline
242 int net_eq(const struct net *net1, const struct net *net2)
243 {
244 	return 1;
245 }
246 
247 #define net_drop_ns NULL
248 #endif
249 
250 
251 typedef struct {
252 #ifdef CONFIG_NET_NS
253 	struct net *net;
254 #endif
255 } possible_net_t;
256 
257 static inline void write_pnet(possible_net_t *pnet, struct net *net)
258 {
259 #ifdef CONFIG_NET_NS
260 	pnet->net = net;
261 #endif
262 }
263 
264 static inline struct net *read_pnet(const possible_net_t *pnet)
265 {
266 #ifdef CONFIG_NET_NS
267 	return pnet->net;
268 #else
269 	return &init_net;
270 #endif
271 }
272 
273 #define for_each_net(VAR)				\
274 	list_for_each_entry(VAR, &net_namespace_list, list)
275 
276 #define for_each_net_rcu(VAR)				\
277 	list_for_each_entry_rcu(VAR, &net_namespace_list, list)
278 
279 #ifdef CONFIG_NET_NS
280 #define __net_init
281 #define __net_exit
282 #define __net_initdata
283 #define __net_initconst
284 #else
285 #define __net_init	__init
286 #define __net_exit	__ref
287 #define __net_initdata	__initdata
288 #define __net_initconst	__initconst
289 #endif
290 
291 int peernet2id_alloc(struct net *net, struct net *peer);
292 int peernet2id(struct net *net, struct net *peer);
293 bool peernet_has_id(struct net *net, struct net *peer);
294 struct net *get_net_ns_by_id(struct net *net, int id);
295 
296 struct pernet_operations {
297 	struct list_head list;
298 	int (*init)(struct net *net);
299 	void (*exit)(struct net *net);
300 	void (*exit_batch)(struct list_head *net_exit_list);
301 	unsigned int *id;
302 	size_t size;
303 };
304 
305 /*
306  * Use these carefully.  If you implement a network device and it
307  * needs per network namespace operations use device pernet operations,
308  * otherwise use pernet subsys operations.
309  *
310  * Network interfaces need to be removed from a dying netns _before_
311  * subsys notifiers can be called, as most of the network code cleanup
312  * (which is done from subsys notifiers) runs with the assumption that
313  * dev_remove_pack has been called so no new packets will arrive during
314  * and after the cleanup functions have been called.  dev_remove_pack
315  * is not per namespace so instead the guarantee of no more packets
316  * arriving in a network namespace is provided by ensuring that all
317  * network devices and all sockets have left the network namespace
318  * before the cleanup methods are called.
319  *
320  * For the longest time the ipv4 icmp code was registered as a pernet
321  * device which caused kernel oops, and panics during network
322  * namespace cleanup.   So please don't get this wrong.
323  */
324 int register_pernet_subsys(struct pernet_operations *);
325 void unregister_pernet_subsys(struct pernet_operations *);
326 int register_pernet_device(struct pernet_operations *);
327 void unregister_pernet_device(struct pernet_operations *);
328 
329 struct ctl_table;
330 struct ctl_table_header;
331 
332 #ifdef CONFIG_SYSCTL
333 int net_sysctl_init(void);
334 struct ctl_table_header *register_net_sysctl(struct net *net, const char *path,
335 					     struct ctl_table *table);
336 void unregister_net_sysctl_table(struct ctl_table_header *header);
337 #else
338 static inline int net_sysctl_init(void) { return 0; }
339 static inline struct ctl_table_header *register_net_sysctl(struct net *net,
340 	const char *path, struct ctl_table *table)
341 {
342 	return NULL;
343 }
344 static inline void unregister_net_sysctl_table(struct ctl_table_header *header)
345 {
346 }
347 #endif
348 
349 static inline int rt_genid_ipv4(struct net *net)
350 {
351 	return atomic_read(&net->ipv4.rt_genid);
352 }
353 
354 static inline void rt_genid_bump_ipv4(struct net *net)
355 {
356 	atomic_inc(&net->ipv4.rt_genid);
357 }
358 
359 extern void (*__fib6_flush_trees)(struct net *net);
360 static inline void rt_genid_bump_ipv6(struct net *net)
361 {
362 	if (__fib6_flush_trees)
363 		__fib6_flush_trees(net);
364 }
365 
366 #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
367 static inline struct netns_ieee802154_lowpan *
368 net_ieee802154_lowpan(struct net *net)
369 {
370 	return &net->ieee802154_lowpan;
371 }
372 #endif
373 
374 /* For callers who don't really care about whether it's IPv4 or IPv6 */
375 static inline void rt_genid_bump_all(struct net *net)
376 {
377 	rt_genid_bump_ipv4(net);
378 	rt_genid_bump_ipv6(net);
379 }
380 
381 static inline int fnhe_genid(struct net *net)
382 {
383 	return atomic_read(&net->fnhe_genid);
384 }
385 
386 static inline void fnhe_genid_bump(struct net *net)
387 {
388 	atomic_inc(&net->fnhe_genid);
389 }
390 
391 #endif /* __NET_NET_NAMESPACE_H */
392