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 struct ucounts *ucounts;
64 spinlock_t nsid_lock;
65 struct idr netns_ids;
66
67 struct ns_common ns;
68
69 struct proc_dir_entry *proc_net;
70 struct proc_dir_entry *proc_net_stat;
71
72 #ifdef CONFIG_SYSCTL
73 struct ctl_table_set sysctls;
74 #endif
75
76 struct sock *rtnl; /* rtnetlink socket */
77 struct sock *genl_sock;
78
79 struct list_head dev_base_head;
80 struct hlist_head *dev_name_head;
81 struct hlist_head *dev_index_head;
82 unsigned int dev_base_seq; /* protected by rtnl_mutex */
83 int ifindex;
84 unsigned int dev_unreg_count;
85
86 /* core fib_rules */
87 struct list_head rules_ops;
88
89
90 struct net_device *loopback_dev; /* The loopback */
91 struct netns_core core;
92 struct netns_mib mib;
93 struct netns_packet packet;
94 struct netns_unix unx;
95 struct netns_ipv4 ipv4;
96 #if IS_ENABLED(CONFIG_IPV6)
97 struct netns_ipv6 ipv6;
98 #endif
99 #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
100 struct netns_ieee802154_lowpan ieee802154_lowpan;
101 #endif
102 #if defined(CONFIG_IP_SCTP) || defined(CONFIG_IP_SCTP_MODULE)
103 struct netns_sctp sctp;
104 #endif
105 #if defined(CONFIG_IP_DCCP) || defined(CONFIG_IP_DCCP_MODULE)
106 struct netns_dccp dccp;
107 #endif
108 #ifdef CONFIG_NETFILTER
109 struct netns_nf nf;
110 struct netns_xt xt;
111 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
112 struct netns_ct ct;
113 #endif
114 #if defined(CONFIG_NF_TABLES) || defined(CONFIG_NF_TABLES_MODULE)
115 struct netns_nftables nft;
116 #endif
117 #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
118 struct netns_nf_frag nf_frag;
119 #endif
120 struct sock *nfnl;
121 struct sock *nfnl_stash;
122 #if IS_ENABLED(CONFIG_NETFILTER_NETLINK_ACCT)
123 struct list_head nfnl_acct_list;
124 #endif
125 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
126 struct list_head nfct_timeout_list;
127 #endif
128 #endif
129 #ifdef CONFIG_WEXT_CORE
130 struct sk_buff_head wext_nlevents;
131 #endif
132 struct net_generic __rcu *gen;
133
134 /* Note : following structs are cache line aligned */
135 #ifdef CONFIG_XFRM
136 struct netns_xfrm xfrm;
137 #endif
138 #if IS_ENABLED(CONFIG_IP_VS)
139 struct netns_ipvs *ipvs;
140 #endif
141 #if IS_ENABLED(CONFIG_MPLS)
142 struct netns_mpls mpls;
143 #endif
144 struct sock *diag_nlsk;
145 atomic_t fnhe_genid;
146 };
147
148 #include <linux/seq_file_net.h>
149
150 /* Init's network namespace */
151 extern struct net init_net;
152
153 #ifdef CONFIG_NET_NS
154 struct net *copy_net_ns(unsigned long flags, struct user_namespace *user_ns,
155 struct net *old_net);
156
157 #else /* CONFIG_NET_NS */
158 #include <linux/sched.h>
159 #include <linux/nsproxy.h>
copy_net_ns(unsigned long flags,struct user_namespace * user_ns,struct net * old_net)160 static inline struct net *copy_net_ns(unsigned long flags,
161 struct user_namespace *user_ns, struct net *old_net)
162 {
163 if (flags & CLONE_NEWNET)
164 return ERR_PTR(-EINVAL);
165 return old_net;
166 }
167 #endif /* CONFIG_NET_NS */
168
169
170 extern struct list_head net_namespace_list;
171
172 struct net *get_net_ns_by_pid(pid_t pid);
173 struct net *get_net_ns_by_fd(int fd);
174
175 #ifdef CONFIG_SYSCTL
176 void ipx_register_sysctl(void);
177 void ipx_unregister_sysctl(void);
178 #else
179 #define ipx_register_sysctl()
180 #define ipx_unregister_sysctl()
181 #endif
182
183 #ifdef CONFIG_NET_NS
184 void __put_net(struct net *net);
185
get_net(struct net * net)186 static inline struct net *get_net(struct net *net)
187 {
188 atomic_inc(&net->count);
189 return net;
190 }
191
maybe_get_net(struct net * net)192 static inline struct net *maybe_get_net(struct net *net)
193 {
194 /* Used when we know struct net exists but we
195 * aren't guaranteed a previous reference count
196 * exists. If the reference count is zero this
197 * function fails and returns NULL.
198 */
199 if (!atomic_inc_not_zero(&net->count))
200 net = NULL;
201 return net;
202 }
203
put_net(struct net * net)204 static inline void put_net(struct net *net)
205 {
206 if (atomic_dec_and_test(&net->count))
207 __put_net(net);
208 }
209
210 static inline
net_eq(const struct net * net1,const struct net * net2)211 int net_eq(const struct net *net1, const struct net *net2)
212 {
213 return net1 == net2;
214 }
215
check_net(const struct net * net)216 static inline int check_net(const struct net *net)
217 {
218 return atomic_read(&net->count) != 0;
219 }
220
221 void net_drop_ns(void *);
222
223 #else
224
get_net(struct net * net)225 static inline struct net *get_net(struct net *net)
226 {
227 return net;
228 }
229
put_net(struct net * net)230 static inline void put_net(struct net *net)
231 {
232 }
233
maybe_get_net(struct net * net)234 static inline struct net *maybe_get_net(struct net *net)
235 {
236 return net;
237 }
238
239 static inline
net_eq(const struct net * net1,const struct net * net2)240 int net_eq(const struct net *net1, const struct net *net2)
241 {
242 return 1;
243 }
244
check_net(const struct net * net)245 static inline int check_net(const struct net *net)
246 {
247 return 1;
248 }
249
250 #define net_drop_ns NULL
251 #endif
252
253
254 typedef struct {
255 #ifdef CONFIG_NET_NS
256 struct net *net;
257 #endif
258 } possible_net_t;
259
write_pnet(possible_net_t * pnet,struct net * net)260 static inline void write_pnet(possible_net_t *pnet, struct net *net)
261 {
262 #ifdef CONFIG_NET_NS
263 pnet->net = net;
264 #endif
265 }
266
read_pnet(const possible_net_t * pnet)267 static inline struct net *read_pnet(const possible_net_t *pnet)
268 {
269 #ifdef CONFIG_NET_NS
270 return pnet->net;
271 #else
272 return &init_net;
273 #endif
274 }
275
276 #define for_each_net(VAR) \
277 list_for_each_entry(VAR, &net_namespace_list, list)
278
279 #define for_each_net_rcu(VAR) \
280 list_for_each_entry_rcu(VAR, &net_namespace_list, list)
281
282 #ifdef CONFIG_NET_NS
283 #define __net_init
284 #define __net_exit
285 #define __net_initdata
286 #define __net_initconst
287 #else
288 #define __net_init __init
289 #define __net_exit __ref
290 #define __net_initdata __initdata
291 #define __net_initconst __initconst
292 #endif
293
294 int peernet2id_alloc(struct net *net, struct net *peer);
295 int peernet2id(struct net *net, struct net *peer);
296 bool peernet_has_id(struct net *net, struct net *peer);
297 struct net *get_net_ns_by_id(struct net *net, int id);
298
299 struct pernet_operations {
300 struct list_head list;
301 int (*init)(struct net *net);
302 void (*exit)(struct net *net);
303 void (*exit_batch)(struct list_head *net_exit_list);
304 int *id;
305 size_t size;
306 };
307
308 /*
309 * Use these carefully. If you implement a network device and it
310 * needs per network namespace operations use device pernet operations,
311 * otherwise use pernet subsys operations.
312 *
313 * Network interfaces need to be removed from a dying netns _before_
314 * subsys notifiers can be called, as most of the network code cleanup
315 * (which is done from subsys notifiers) runs with the assumption that
316 * dev_remove_pack has been called so no new packets will arrive during
317 * and after the cleanup functions have been called. dev_remove_pack
318 * is not per namespace so instead the guarantee of no more packets
319 * arriving in a network namespace is provided by ensuring that all
320 * network devices and all sockets have left the network namespace
321 * before the cleanup methods are called.
322 *
323 * For the longest time the ipv4 icmp code was registered as a pernet
324 * device which caused kernel oops, and panics during network
325 * namespace cleanup. So please don't get this wrong.
326 */
327 int register_pernet_subsys(struct pernet_operations *);
328 void unregister_pernet_subsys(struct pernet_operations *);
329 int register_pernet_device(struct pernet_operations *);
330 void unregister_pernet_device(struct pernet_operations *);
331
332 struct ctl_table;
333 struct ctl_table_header;
334
335 #ifdef CONFIG_SYSCTL
336 int net_sysctl_init(void);
337 struct ctl_table_header *register_net_sysctl(struct net *net, const char *path,
338 struct ctl_table *table);
339 void unregister_net_sysctl_table(struct ctl_table_header *header);
340 #else
net_sysctl_init(void)341 static inline int net_sysctl_init(void) { return 0; }
register_net_sysctl(struct net * net,const char * path,struct ctl_table * table)342 static inline struct ctl_table_header *register_net_sysctl(struct net *net,
343 const char *path, struct ctl_table *table)
344 {
345 return NULL;
346 }
unregister_net_sysctl_table(struct ctl_table_header * header)347 static inline void unregister_net_sysctl_table(struct ctl_table_header *header)
348 {
349 }
350 #endif
351
rt_genid_ipv4(struct net * net)352 static inline int rt_genid_ipv4(struct net *net)
353 {
354 return atomic_read(&net->ipv4.rt_genid);
355 }
356
rt_genid_bump_ipv4(struct net * net)357 static inline void rt_genid_bump_ipv4(struct net *net)
358 {
359 atomic_inc(&net->ipv4.rt_genid);
360 }
361
362 extern void (*__fib6_flush_trees)(struct net *net);
rt_genid_bump_ipv6(struct net * net)363 static inline void rt_genid_bump_ipv6(struct net *net)
364 {
365 if (__fib6_flush_trees)
366 __fib6_flush_trees(net);
367 }
368
369 #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
370 static inline struct netns_ieee802154_lowpan *
net_ieee802154_lowpan(struct net * net)371 net_ieee802154_lowpan(struct net *net)
372 {
373 return &net->ieee802154_lowpan;
374 }
375 #endif
376
377 /* For callers who don't really care about whether it's IPv4 or IPv6 */
rt_genid_bump_all(struct net * net)378 static inline void rt_genid_bump_all(struct net *net)
379 {
380 rt_genid_bump_ipv4(net);
381 rt_genid_bump_ipv6(net);
382 }
383
fnhe_genid(struct net * net)384 static inline int fnhe_genid(struct net *net)
385 {
386 return atomic_read(&net->fnhe_genid);
387 }
388
fnhe_genid_bump(struct net * net)389 static inline void fnhe_genid_bump(struct net *net)
390 {
391 atomic_inc(&net->fnhe_genid);
392 }
393
394 #endif /* __NET_NET_NAMESPACE_H */
395