xref: /openbmc/linux/include/net/net_namespace.h (revision c8dbaa22)
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/refcount.h>
9 #include <linux/workqueue.h>
10 #include <linux/list.h>
11 #include <linux/sysctl.h>
12 
13 #include <net/flow.h>
14 #include <net/netns/core.h>
15 #include <net/netns/mib.h>
16 #include <net/netns/unix.h>
17 #include <net/netns/packet.h>
18 #include <net/netns/ipv4.h>
19 #include <net/netns/ipv6.h>
20 #include <net/netns/ieee802154_6lowpan.h>
21 #include <net/netns/sctp.h>
22 #include <net/netns/dccp.h>
23 #include <net/netns/netfilter.h>
24 #include <net/netns/x_tables.h>
25 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
26 #include <net/netns/conntrack.h>
27 #endif
28 #include <net/netns/nftables.h>
29 #include <net/netns/xfrm.h>
30 #include <net/netns/mpls.h>
31 #include <net/netns/can.h>
32 #include <linux/ns_common.h>
33 #include <linux/idr.h>
34 #include <linux/skbuff.h>
35 
36 struct user_namespace;
37 struct proc_dir_entry;
38 struct net_device;
39 struct sock;
40 struct ctl_table_header;
41 struct net_generic;
42 struct sock;
43 struct netns_ipvs;
44 
45 
46 #define NETDEV_HASHBITS    8
47 #define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS)
48 
49 struct net {
50 	refcount_t		passive;	/* To decided when the network
51 						 * namespace should be freed.
52 						 */
53 	atomic_t		count;		/* To decided when the network
54 						 *  namespace should be shut down.
55 						 */
56 	spinlock_t		rules_mod_lock;
57 
58 	atomic64_t		cookie_gen;
59 
60 	struct list_head	list;		/* list of network namespaces */
61 	struct list_head	cleanup_list;	/* namespaces on death row */
62 	struct list_head	exit_list;	/* Use only net_mutex */
63 
64 	struct user_namespace   *user_ns;	/* Owning user namespace */
65 	struct ucounts		*ucounts;
66 	spinlock_t		nsid_lock;
67 	struct idr		netns_ids;
68 
69 	struct ns_common	ns;
70 
71 	struct proc_dir_entry 	*proc_net;
72 	struct proc_dir_entry 	*proc_net_stat;
73 
74 #ifdef CONFIG_SYSCTL
75 	struct ctl_table_set	sysctls;
76 #endif
77 
78 	struct sock 		*rtnl;			/* rtnetlink socket */
79 	struct sock		*genl_sock;
80 
81 	struct list_head 	dev_base_head;
82 	struct hlist_head 	*dev_name_head;
83 	struct hlist_head	*dev_index_head;
84 	unsigned int		dev_base_seq;	/* protected by rtnl_mutex */
85 	int			ifindex;
86 	unsigned int		dev_unreg_count;
87 
88 	/* core fib_rules */
89 	struct list_head	rules_ops;
90 
91 
92 	struct net_device       *loopback_dev;          /* The loopback */
93 	struct netns_core	core;
94 	struct netns_mib	mib;
95 	struct netns_packet	packet;
96 	struct netns_unix	unx;
97 	struct netns_ipv4	ipv4;
98 #if IS_ENABLED(CONFIG_IPV6)
99 	struct netns_ipv6	ipv6;
100 #endif
101 #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
102 	struct netns_ieee802154_lowpan	ieee802154_lowpan;
103 #endif
104 #if defined(CONFIG_IP_SCTP) || defined(CONFIG_IP_SCTP_MODULE)
105 	struct netns_sctp	sctp;
106 #endif
107 #if defined(CONFIG_IP_DCCP) || defined(CONFIG_IP_DCCP_MODULE)
108 	struct netns_dccp	dccp;
109 #endif
110 #ifdef CONFIG_NETFILTER
111 	struct netns_nf		nf;
112 	struct netns_xt		xt;
113 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
114 	struct netns_ct		ct;
115 #endif
116 #if defined(CONFIG_NF_TABLES) || defined(CONFIG_NF_TABLES_MODULE)
117 	struct netns_nftables	nft;
118 #endif
119 #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
120 	struct netns_nf_frag	nf_frag;
121 #endif
122 	struct sock		*nfnl;
123 	struct sock		*nfnl_stash;
124 #if IS_ENABLED(CONFIG_NETFILTER_NETLINK_ACCT)
125 	struct list_head        nfnl_acct_list;
126 #endif
127 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
128 	struct list_head	nfct_timeout_list;
129 #endif
130 #endif
131 #ifdef CONFIG_WEXT_CORE
132 	struct sk_buff_head	wext_nlevents;
133 #endif
134 	struct net_generic __rcu	*gen;
135 
136 	/* Note : following structs are cache line aligned */
137 #ifdef CONFIG_XFRM
138 	struct netns_xfrm	xfrm;
139 #endif
140 #if IS_ENABLED(CONFIG_IP_VS)
141 	struct netns_ipvs	*ipvs;
142 #endif
143 #if IS_ENABLED(CONFIG_MPLS)
144 	struct netns_mpls	mpls;
145 #endif
146 #if IS_ENABLED(CONFIG_CAN)
147 	struct netns_can	can;
148 #endif
149 	struct sock		*diag_nlsk;
150 	atomic_t		fnhe_genid;
151 } __randomize_layout;
152 
153 #include <linux/seq_file_net.h>
154 
155 /* Init's network namespace */
156 extern struct net init_net;
157 
158 #ifdef CONFIG_NET_NS
159 struct net *copy_net_ns(unsigned long flags, struct user_namespace *user_ns,
160 			struct net *old_net);
161 
162 void net_ns_barrier(void);
163 #else /* CONFIG_NET_NS */
164 #include <linux/sched.h>
165 #include <linux/nsproxy.h>
166 static inline struct net *copy_net_ns(unsigned long flags,
167 	struct user_namespace *user_ns, struct net *old_net)
168 {
169 	if (flags & CLONE_NEWNET)
170 		return ERR_PTR(-EINVAL);
171 	return old_net;
172 }
173 
174 static inline void net_ns_barrier(void) {}
175 #endif /* CONFIG_NET_NS */
176 
177 
178 extern struct list_head net_namespace_list;
179 
180 struct net *get_net_ns_by_pid(pid_t pid);
181 struct net *get_net_ns_by_fd(int fd);
182 
183 #ifdef CONFIG_SYSCTL
184 void ipx_register_sysctl(void);
185 void ipx_unregister_sysctl(void);
186 #else
187 #define ipx_register_sysctl()
188 #define ipx_unregister_sysctl()
189 #endif
190 
191 #ifdef CONFIG_NET_NS
192 void __put_net(struct net *net);
193 
194 static inline struct net *get_net(struct net *net)
195 {
196 	atomic_inc(&net->count);
197 	return net;
198 }
199 
200 static inline struct net *maybe_get_net(struct net *net)
201 {
202 	/* Used when we know struct net exists but we
203 	 * aren't guaranteed a previous reference count
204 	 * exists.  If the reference count is zero this
205 	 * function fails and returns NULL.
206 	 */
207 	if (!atomic_inc_not_zero(&net->count))
208 		net = NULL;
209 	return net;
210 }
211 
212 static inline void put_net(struct net *net)
213 {
214 	if (atomic_dec_and_test(&net->count))
215 		__put_net(net);
216 }
217 
218 static inline
219 int net_eq(const struct net *net1, const struct net *net2)
220 {
221 	return net1 == net2;
222 }
223 
224 void net_drop_ns(void *);
225 
226 #else
227 
228 static inline struct net *get_net(struct net *net)
229 {
230 	return net;
231 }
232 
233 static inline void put_net(struct net *net)
234 {
235 }
236 
237 static inline struct net *maybe_get_net(struct net *net)
238 {
239 	return net;
240 }
241 
242 static inline
243 int net_eq(const struct net *net1, const struct net *net2)
244 {
245 	return 1;
246 }
247 
248 #define net_drop_ns NULL
249 #endif
250 
251 
252 typedef struct {
253 #ifdef CONFIG_NET_NS
254 	struct net *net;
255 #endif
256 } possible_net_t;
257 
258 static inline void write_pnet(possible_net_t *pnet, struct net *net)
259 {
260 #ifdef CONFIG_NET_NS
261 	pnet->net = net;
262 #endif
263 }
264 
265 static inline struct net *read_pnet(const possible_net_t *pnet)
266 {
267 #ifdef CONFIG_NET_NS
268 	return pnet->net;
269 #else
270 	return &init_net;
271 #endif
272 }
273 
274 #define for_each_net(VAR)				\
275 	list_for_each_entry(VAR, &net_namespace_list, list)
276 
277 #define for_each_net_rcu(VAR)				\
278 	list_for_each_entry_rcu(VAR, &net_namespace_list, list)
279 
280 #ifdef CONFIG_NET_NS
281 #define __net_init
282 #define __net_exit
283 #define __net_initdata
284 #define __net_initconst
285 #else
286 #define __net_init	__init
287 #define __net_exit	__ref
288 #define __net_initdata	__initdata
289 #define __net_initconst	__initconst
290 #endif
291 
292 int peernet2id_alloc(struct net *net, struct net *peer);
293 int peernet2id(struct net *net, struct net *peer);
294 bool peernet_has_id(struct net *net, struct net *peer);
295 struct net *get_net_ns_by_id(struct net *net, int id);
296 
297 struct pernet_operations {
298 	struct list_head list;
299 	int (*init)(struct net *net);
300 	void (*exit)(struct net *net);
301 	void (*exit_batch)(struct list_head *net_exit_list);
302 	unsigned int *id;
303 	size_t size;
304 };
305 
306 /*
307  * Use these carefully.  If you implement a network device and it
308  * needs per network namespace operations use device pernet operations,
309  * otherwise use pernet subsys operations.
310  *
311  * Network interfaces need to be removed from a dying netns _before_
312  * subsys notifiers can be called, as most of the network code cleanup
313  * (which is done from subsys notifiers) runs with the assumption that
314  * dev_remove_pack has been called so no new packets will arrive during
315  * and after the cleanup functions have been called.  dev_remove_pack
316  * is not per namespace so instead the guarantee of no more packets
317  * arriving in a network namespace is provided by ensuring that all
318  * network devices and all sockets have left the network namespace
319  * before the cleanup methods are called.
320  *
321  * For the longest time the ipv4 icmp code was registered as a pernet
322  * device which caused kernel oops, and panics during network
323  * namespace cleanup.   So please don't get this wrong.
324  */
325 int register_pernet_subsys(struct pernet_operations *);
326 void unregister_pernet_subsys(struct pernet_operations *);
327 int register_pernet_device(struct pernet_operations *);
328 void unregister_pernet_device(struct pernet_operations *);
329 
330 struct ctl_table;
331 struct ctl_table_header;
332 
333 #ifdef CONFIG_SYSCTL
334 int net_sysctl_init(void);
335 struct ctl_table_header *register_net_sysctl(struct net *net, const char *path,
336 					     struct ctl_table *table);
337 void unregister_net_sysctl_table(struct ctl_table_header *header);
338 #else
339 static inline int net_sysctl_init(void) { return 0; }
340 static inline struct ctl_table_header *register_net_sysctl(struct net *net,
341 	const char *path, struct ctl_table *table)
342 {
343 	return NULL;
344 }
345 static inline void unregister_net_sysctl_table(struct ctl_table_header *header)
346 {
347 }
348 #endif
349 
350 static inline int rt_genid_ipv4(struct net *net)
351 {
352 	return atomic_read(&net->ipv4.rt_genid);
353 }
354 
355 static inline void rt_genid_bump_ipv4(struct net *net)
356 {
357 	atomic_inc(&net->ipv4.rt_genid);
358 }
359 
360 extern void (*__fib6_flush_trees)(struct net *net);
361 static inline void rt_genid_bump_ipv6(struct net *net)
362 {
363 	if (__fib6_flush_trees)
364 		__fib6_flush_trees(net);
365 }
366 
367 #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
368 static inline struct netns_ieee802154_lowpan *
369 net_ieee802154_lowpan(struct net *net)
370 {
371 	return &net->ieee802154_lowpan;
372 }
373 #endif
374 
375 /* For callers who don't really care about whether it's IPv4 or IPv6 */
376 static inline void rt_genid_bump_all(struct net *net)
377 {
378 	rt_genid_bump_ipv4(net);
379 	rt_genid_bump_ipv6(net);
380 }
381 
382 static inline int fnhe_genid(struct net *net)
383 {
384 	return atomic_read(&net->fnhe_genid);
385 }
386 
387 static inline void fnhe_genid_bump(struct net *net)
388 {
389 	atomic_inc(&net->fnhe_genid);
390 }
391 
392 #endif /* __NET_NET_NAMESPACE_H */
393