xref: /openbmc/linux/include/net/net_namespace.h (revision 80483c3a)
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 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
125 	struct list_head	nfct_timeout_list;
126 #endif
127 #endif
128 #ifdef CONFIG_WEXT_CORE
129 	struct sk_buff_head	wext_nlevents;
130 #endif
131 	struct net_generic __rcu	*gen;
132 
133 	/* Note : following structs are cache line aligned */
134 #ifdef CONFIG_XFRM
135 	struct netns_xfrm	xfrm;
136 #endif
137 #if IS_ENABLED(CONFIG_IP_VS)
138 	struct netns_ipvs	*ipvs;
139 #endif
140 #if IS_ENABLED(CONFIG_MPLS)
141 	struct netns_mpls	mpls;
142 #endif
143 	struct sock		*diag_nlsk;
144 	atomic_t		fnhe_genid;
145 };
146 
147 #include <linux/seq_file_net.h>
148 
149 /* Init's network namespace */
150 extern struct net init_net;
151 
152 #ifdef CONFIG_NET_NS
153 struct net *copy_net_ns(unsigned long flags, struct user_namespace *user_ns,
154 			struct net *old_net);
155 
156 #else /* CONFIG_NET_NS */
157 #include <linux/sched.h>
158 #include <linux/nsproxy.h>
159 static inline struct net *copy_net_ns(unsigned long flags,
160 	struct user_namespace *user_ns, struct net *old_net)
161 {
162 	if (flags & CLONE_NEWNET)
163 		return ERR_PTR(-EINVAL);
164 	return old_net;
165 }
166 #endif /* CONFIG_NET_NS */
167 
168 
169 extern struct list_head net_namespace_list;
170 
171 struct net *get_net_ns_by_pid(pid_t pid);
172 struct net *get_net_ns_by_fd(int pid);
173 
174 #ifdef CONFIG_SYSCTL
175 void ipx_register_sysctl(void);
176 void ipx_unregister_sysctl(void);
177 #else
178 #define ipx_register_sysctl()
179 #define ipx_unregister_sysctl()
180 #endif
181 
182 #ifdef CONFIG_NET_NS
183 void __put_net(struct net *net);
184 
185 static inline struct net *get_net(struct net *net)
186 {
187 	atomic_inc(&net->count);
188 	return net;
189 }
190 
191 static inline struct net *maybe_get_net(struct net *net)
192 {
193 	/* Used when we know struct net exists but we
194 	 * aren't guaranteed a previous reference count
195 	 * exists.  If the reference count is zero this
196 	 * function fails and returns NULL.
197 	 */
198 	if (!atomic_inc_not_zero(&net->count))
199 		net = NULL;
200 	return net;
201 }
202 
203 static inline void put_net(struct net *net)
204 {
205 	if (atomic_dec_and_test(&net->count))
206 		__put_net(net);
207 }
208 
209 static inline
210 int net_eq(const struct net *net1, const struct net *net2)
211 {
212 	return net1 == net2;
213 }
214 
215 void net_drop_ns(void *);
216 
217 #else
218 
219 static inline struct net *get_net(struct net *net)
220 {
221 	return net;
222 }
223 
224 static inline void put_net(struct net *net)
225 {
226 }
227 
228 static inline struct net *maybe_get_net(struct net *net)
229 {
230 	return net;
231 }
232 
233 static inline
234 int net_eq(const struct net *net1, const struct net *net2)
235 {
236 	return 1;
237 }
238 
239 #define net_drop_ns NULL
240 #endif
241 
242 
243 typedef struct {
244 #ifdef CONFIG_NET_NS
245 	struct net *net;
246 #endif
247 } possible_net_t;
248 
249 static inline void write_pnet(possible_net_t *pnet, struct net *net)
250 {
251 #ifdef CONFIG_NET_NS
252 	pnet->net = net;
253 #endif
254 }
255 
256 static inline struct net *read_pnet(const possible_net_t *pnet)
257 {
258 #ifdef CONFIG_NET_NS
259 	return pnet->net;
260 #else
261 	return &init_net;
262 #endif
263 }
264 
265 #define for_each_net(VAR)				\
266 	list_for_each_entry(VAR, &net_namespace_list, list)
267 
268 #define for_each_net_rcu(VAR)				\
269 	list_for_each_entry_rcu(VAR, &net_namespace_list, list)
270 
271 #ifdef CONFIG_NET_NS
272 #define __net_init
273 #define __net_exit
274 #define __net_initdata
275 #define __net_initconst
276 #else
277 #define __net_init	__init
278 #define __net_exit	__ref
279 #define __net_initdata	__initdata
280 #define __net_initconst	__initconst
281 #endif
282 
283 int peernet2id_alloc(struct net *net, struct net *peer);
284 int peernet2id(struct net *net, struct net *peer);
285 bool peernet_has_id(struct net *net, struct net *peer);
286 struct net *get_net_ns_by_id(struct net *net, int id);
287 
288 struct pernet_operations {
289 	struct list_head list;
290 	int (*init)(struct net *net);
291 	void (*exit)(struct net *net);
292 	void (*exit_batch)(struct list_head *net_exit_list);
293 	int *id;
294 	size_t size;
295 };
296 
297 /*
298  * Use these carefully.  If you implement a network device and it
299  * needs per network namespace operations use device pernet operations,
300  * otherwise use pernet subsys operations.
301  *
302  * Network interfaces need to be removed from a dying netns _before_
303  * subsys notifiers can be called, as most of the network code cleanup
304  * (which is done from subsys notifiers) runs with the assumption that
305  * dev_remove_pack has been called so no new packets will arrive during
306  * and after the cleanup functions have been called.  dev_remove_pack
307  * is not per namespace so instead the guarantee of no more packets
308  * arriving in a network namespace is provided by ensuring that all
309  * network devices and all sockets have left the network namespace
310  * before the cleanup methods are called.
311  *
312  * For the longest time the ipv4 icmp code was registered as a pernet
313  * device which caused kernel oops, and panics during network
314  * namespace cleanup.   So please don't get this wrong.
315  */
316 int register_pernet_subsys(struct pernet_operations *);
317 void unregister_pernet_subsys(struct pernet_operations *);
318 int register_pernet_device(struct pernet_operations *);
319 void unregister_pernet_device(struct pernet_operations *);
320 
321 struct ctl_table;
322 struct ctl_table_header;
323 
324 #ifdef CONFIG_SYSCTL
325 int net_sysctl_init(void);
326 struct ctl_table_header *register_net_sysctl(struct net *net, const char *path,
327 					     struct ctl_table *table);
328 void unregister_net_sysctl_table(struct ctl_table_header *header);
329 #else
330 static inline int net_sysctl_init(void) { return 0; }
331 static inline struct ctl_table_header *register_net_sysctl(struct net *net,
332 	const char *path, struct ctl_table *table)
333 {
334 	return NULL;
335 }
336 static inline void unregister_net_sysctl_table(struct ctl_table_header *header)
337 {
338 }
339 #endif
340 
341 static inline int rt_genid_ipv4(struct net *net)
342 {
343 	return atomic_read(&net->ipv4.rt_genid);
344 }
345 
346 static inline void rt_genid_bump_ipv4(struct net *net)
347 {
348 	atomic_inc(&net->ipv4.rt_genid);
349 }
350 
351 extern void (*__fib6_flush_trees)(struct net *net);
352 static inline void rt_genid_bump_ipv6(struct net *net)
353 {
354 	if (__fib6_flush_trees)
355 		__fib6_flush_trees(net);
356 }
357 
358 #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
359 static inline struct netns_ieee802154_lowpan *
360 net_ieee802154_lowpan(struct net *net)
361 {
362 	return &net->ieee802154_lowpan;
363 }
364 #endif
365 
366 /* For callers who don't really care about whether it's IPv4 or IPv6 */
367 static inline void rt_genid_bump_all(struct net *net)
368 {
369 	rt_genid_bump_ipv4(net);
370 	rt_genid_bump_ipv6(net);
371 }
372 
373 static inline int fnhe_genid(struct net *net)
374 {
375 	return atomic_read(&net->fnhe_genid);
376 }
377 
378 static inline void fnhe_genid_bump(struct net *net)
379 {
380 	atomic_inc(&net->fnhe_genid);
381 }
382 
383 #endif /* __NET_NET_NAMESPACE_H */
384