net_namespace.h 7.4 KB

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  1. /*
  2. * Operations on the network namespace
  3. */
  4. #ifndef __NET_NET_NAMESPACE_H
  5. #define __NET_NET_NAMESPACE_H
  6. #include <linux/atomic.h>
  7. #include <linux/workqueue.h>
  8. #include <linux/list.h>
  9. #include <linux/sysctl.h>
  10. #include <net/flow.h>
  11. #include <net/netns/core.h>
  12. #include <net/netns/mib.h>
  13. #include <net/netns/unix.h>
  14. #include <net/netns/packet.h>
  15. #include <net/netns/ipv4.h>
  16. #include <net/netns/ipv6.h>
  17. #include <net/netns/dccp.h>
  18. #include <net/netns/x_tables.h>
  19. #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
  20. #include <net/netns/conntrack.h>
  21. #endif
  22. #include <net/netns/xfrm.h>
  23. struct user_namespace;
  24. struct proc_dir_entry;
  25. struct net_device;
  26. struct sock;
  27. struct ctl_table_header;
  28. struct net_generic;
  29. struct sock;
  30. struct netns_ipvs;
  31. #define NETDEV_HASHBITS 8
  32. #define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS)
  33. struct net {
  34. atomic_t passive; /* To decided when the network
  35. * namespace should be freed.
  36. */
  37. atomic_t count; /* To decided when the network
  38. * namespace should be shut down.
  39. */
  40. #ifdef NETNS_REFCNT_DEBUG
  41. atomic_t use_count; /* To track references we
  42. * destroy on demand
  43. */
  44. #endif
  45. spinlock_t rules_mod_lock;
  46. u32 hash_mix;
  47. struct list_head list; /* list of network namespaces */
  48. struct list_head cleanup_list; /* namespaces on death row */
  49. struct list_head exit_list; /* Use only net_mutex */
  50. struct user_namespace *user_ns; /* Owning user namespace */
  51. unsigned int proc_inum;
  52. struct proc_dir_entry *proc_net;
  53. struct proc_dir_entry *proc_net_stat;
  54. #ifdef CONFIG_SYSCTL
  55. struct ctl_table_set sysctls;
  56. #endif
  57. struct sock *rtnl; /* rtnetlink socket */
  58. struct sock *genl_sock;
  59. struct list_head dev_base_head;
  60. struct hlist_head *dev_name_head;
  61. struct hlist_head *dev_index_head;
  62. unsigned int dev_base_seq; /* protected by rtnl_mutex */
  63. /* core fib_rules */
  64. struct list_head rules_ops;
  65. struct net_device *loopback_dev; /* The loopback */
  66. struct netns_core core;
  67. struct netns_mib mib;
  68. struct netns_packet packet;
  69. struct netns_unix unx;
  70. struct netns_ipv4 ipv4;
  71. #if IS_ENABLED(CONFIG_IPV6)
  72. struct netns_ipv6 ipv6;
  73. #endif
  74. #if defined(CONFIG_IP_DCCP) || defined(CONFIG_IP_DCCP_MODULE)
  75. struct netns_dccp dccp;
  76. #endif
  77. #ifdef CONFIG_NETFILTER
  78. struct netns_xt xt;
  79. #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
  80. struct netns_ct ct;
  81. #endif
  82. struct sock *nfnl;
  83. struct sock *nfnl_stash;
  84. #endif
  85. #ifdef CONFIG_WEXT_CORE
  86. struct sk_buff_head wext_nlevents;
  87. #endif
  88. struct net_generic __rcu *gen;
  89. /* Note : following structs are cache line aligned */
  90. #ifdef CONFIG_XFRM
  91. struct netns_xfrm xfrm;
  92. #endif
  93. struct netns_ipvs *ipvs;
  94. };
  95. /*
  96. * ifindex generation is per-net namespace, and loopback is
  97. * always the 1st device in ns (see net_dev_init), thus any
  98. * loopback device should get ifindex 1
  99. */
  100. #define LOOPBACK_IFINDEX 1
  101. #include <linux/seq_file_net.h>
  102. /* Init's network namespace */
  103. extern struct net init_net;
  104. #ifdef CONFIG_NET
  105. extern struct net *copy_net_ns(unsigned long flags,
  106. struct user_namespace *user_ns, struct net *net_ns);
  107. #else /* CONFIG_NET */
  108. static inline struct net *copy_net_ns(unsigned long flags,
  109. struct user_namespace *user_ns, struct net *net_ns)
  110. {
  111. /* There is nothing to copy so this is a noop */
  112. return net_ns;
  113. }
  114. #endif /* CONFIG_NET */
  115. extern struct list_head net_namespace_list;
  116. extern struct net *get_net_ns_by_pid(pid_t pid);
  117. extern struct net *get_net_ns_by_fd(int pid);
  118. #ifdef CONFIG_NET_NS
  119. extern void __put_net(struct net *net);
  120. static inline struct net *get_net(struct net *net)
  121. {
  122. atomic_inc(&net->count);
  123. return net;
  124. }
  125. static inline struct net *maybe_get_net(struct net *net)
  126. {
  127. /* Used when we know struct net exists but we
  128. * aren't guaranteed a previous reference count
  129. * exists. If the reference count is zero this
  130. * function fails and returns NULL.
  131. */
  132. if (!atomic_inc_not_zero(&net->count))
  133. net = NULL;
  134. return net;
  135. }
  136. static inline void put_net(struct net *net)
  137. {
  138. if (atomic_dec_and_test(&net->count))
  139. __put_net(net);
  140. }
  141. static inline
  142. int net_eq(const struct net *net1, const struct net *net2)
  143. {
  144. return net1 == net2;
  145. }
  146. extern void net_drop_ns(void *);
  147. #else
  148. static inline struct net *get_net(struct net *net)
  149. {
  150. return net;
  151. }
  152. static inline void put_net(struct net *net)
  153. {
  154. }
  155. static inline struct net *maybe_get_net(struct net *net)
  156. {
  157. return net;
  158. }
  159. static inline
  160. int net_eq(const struct net *net1, const struct net *net2)
  161. {
  162. return 1;
  163. }
  164. #define net_drop_ns NULL
  165. #endif
  166. #ifdef NETNS_REFCNT_DEBUG
  167. static inline struct net *hold_net(struct net *net)
  168. {
  169. if (net)
  170. atomic_inc(&net->use_count);
  171. return net;
  172. }
  173. static inline void release_net(struct net *net)
  174. {
  175. if (net)
  176. atomic_dec(&net->use_count);
  177. }
  178. #else
  179. static inline struct net *hold_net(struct net *net)
  180. {
  181. return net;
  182. }
  183. static inline void release_net(struct net *net)
  184. {
  185. }
  186. #endif
  187. #ifdef CONFIG_NET_NS
  188. static inline void write_pnet(struct net **pnet, struct net *net)
  189. {
  190. *pnet = net;
  191. }
  192. static inline struct net *read_pnet(struct net * const *pnet)
  193. {
  194. return *pnet;
  195. }
  196. #else
  197. #define write_pnet(pnet, net) do { (void)(net);} while (0)
  198. #define read_pnet(pnet) (&init_net)
  199. #endif
  200. #define for_each_net(VAR) \
  201. list_for_each_entry(VAR, &net_namespace_list, list)
  202. #define for_each_net_rcu(VAR) \
  203. list_for_each_entry_rcu(VAR, &net_namespace_list, list)
  204. #ifdef CONFIG_NET_NS
  205. #define __net_init
  206. #define __net_exit
  207. #define __net_initdata
  208. #else
  209. #define __net_init __init
  210. #define __net_exit __exit_refok
  211. #define __net_initdata __initdata
  212. #endif
  213. struct pernet_operations {
  214. struct list_head list;
  215. int (*init)(struct net *net);
  216. void (*exit)(struct net *net);
  217. void (*exit_batch)(struct list_head *net_exit_list);
  218. int *id;
  219. size_t size;
  220. };
  221. /*
  222. * Use these carefully. If you implement a network device and it
  223. * needs per network namespace operations use device pernet operations,
  224. * otherwise use pernet subsys operations.
  225. *
  226. * Network interfaces need to be removed from a dying netns _before_
  227. * subsys notifiers can be called, as most of the network code cleanup
  228. * (which is done from subsys notifiers) runs with the assumption that
  229. * dev_remove_pack has been called so no new packets will arrive during
  230. * and after the cleanup functions have been called. dev_remove_pack
  231. * is not per namespace so instead the guarantee of no more packets
  232. * arriving in a network namespace is provided by ensuring that all
  233. * network devices and all sockets have left the network namespace
  234. * before the cleanup methods are called.
  235. *
  236. * For the longest time the ipv4 icmp code was registered as a pernet
  237. * device which caused kernel oops, and panics during network
  238. * namespace cleanup. So please don't get this wrong.
  239. */
  240. extern int register_pernet_subsys(struct pernet_operations *);
  241. extern void unregister_pernet_subsys(struct pernet_operations *);
  242. extern int register_pernet_device(struct pernet_operations *);
  243. extern void unregister_pernet_device(struct pernet_operations *);
  244. struct ctl_path;
  245. struct ctl_table;
  246. struct ctl_table_header;
  247. #ifdef CONFIG_SYSCTL
  248. extern int net_sysctl_init(void);
  249. #else
  250. static inline int net_sysctl_init(void) { return 0; }
  251. #endif
  252. extern struct ctl_table_header *register_net_sysctl_table(struct net *net,
  253. const struct ctl_path *path, struct ctl_table *table);
  254. extern struct ctl_table_header *register_net_sysctl(struct net *net,
  255. const char *path, struct ctl_table *table);
  256. extern void unregister_net_sysctl_table(struct ctl_table_header *header);
  257. #endif /* __NET_NET_NAMESPACE_H */