include/net/net_namespace.h

   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 #else /* CONFIG_NET_NS */
 162 #include <linux/sched.h>
 163 #include <linux/nsproxy.h>
 164 static inline struct net *copy_net_ns(unsigned long flags,
 165         struct user_namespace *user_ns, struct net *old_net)
 166 {
 167         if (flags & CLONE_NEWNET)
 168                 return ERR_PTR(-EINVAL);
 169         return old_net;
 170 }
 171 #endif /* CONFIG_NET_NS */
 172
 173
 174 extern struct list_head net_namespace_list;
 175
 176 struct net *get_net_ns_by_pid(pid_t pid);
 177 struct net *get_net_ns_by_fd(int fd);
 178
 179 #ifdef CONFIG_SYSCTL
 180 void ipx_register_sysctl(void);
 181 void ipx_unregister_sysctl(void);
 182 #else
 183 #define ipx_register_sysctl()
 184 #define ipx_unregister_sysctl()
 185 #endif
 186
 187 #ifdef CONFIG_NET_NS
 188 void __put_net(struct net *net);
 189
 190 static inline struct net *get_net(struct net *net)
 191 {
 192         atomic_inc(&net->count);
 193         return net;
 194 }
 195
 196 static inline struct net *maybe_get_net(struct net *net)
 197 {
 198         /* Used when we know struct net exists but we
 199          * aren't guaranteed a previous reference count
 200          * exists.  If the reference count is zero this
 201          * function fails and returns NULL.
 202          */
 203         if (!atomic_inc_not_zero(&net->count))
 204                 net = NULL;
 205         return net;
 206 }
 207
 208 static inline void put_net(struct net *net)
 209 {
 210         if (atomic_dec_and_test(&net->count))
 211                 __put_net(net);
 212 }
 213
 214 static inline
 215 int net_eq(const struct net *net1, const struct net *net2)
 216 {
 217         return net1 == net2;
 218 }
 219
 220 void net_drop_ns(void *);
 221
 222 #else
 223
 224 static inline struct net *get_net(struct net *net)
 225 {
 226         return net;
 227 }
 228
 229 static inline void put_net(struct net *net)
 230 {
 231 }
 232
 233 static inline struct net *maybe_get_net(struct net *net)
 234 {
 235         return net;
 236 }
 237
 238 static inline
 239 int net_eq(const struct net *net1, const struct net *net2)
 240 {
 241         return 1;
 242 }
 243
 244 #define net_drop_ns NULL
 245 #endif
 246
 247
 248 typedef struct {
 249 #ifdef CONFIG_NET_NS
 250         struct net *net;
 251 #endif
 252 } possible_net_t;
 253
 254 static inline void write_pnet(possible_net_t *pnet, struct net *net)
 255 {
 256 #ifdef CONFIG_NET_NS
 257         pnet->net = net;
 258 #endif
 259 }
 260
 261 static inline struct net *read_pnet(const possible_net_t *pnet)
 262 {
 263 #ifdef CONFIG_NET_NS
 264         return pnet->net;
 265 #else
 266         return &init_net;
 267 #endif
 268 }
 269
 270 #define for_each_net(VAR)                               \
 271         list_for_each_entry(VAR, &net_namespace_list, list)
 272
 273 #define for_each_net_rcu(VAR)                           \
 274         list_for_each_entry_rcu(VAR, &net_namespace_list, list)
 275
 276 #ifdef CONFIG_NET_NS
 277 #define __net_init
 278 #define __net_exit
 279 #define __net_initdata
 280 #define __net_initconst
 281 #else
 282 #define __net_init      __init
 283 #define __net_exit      __ref
 284 #define __net_initdata  __initdata
 285 #define __net_initconst __initconst
 286 #endif
 287
 288 int peernet2id_alloc(struct net *net, struct net *peer);
 289 int peernet2id(struct net *net, struct net *peer);
 290 bool peernet_has_id(struct net *net, struct net *peer);
 291 struct net *get_net_ns_by_id(struct net *net, int id);
 292
 293 struct pernet_operations {
 294         struct list_head list;
 295         int (*init)(struct net *net);
 296         void (*exit)(struct net *net);
 297         void (*exit_batch)(struct list_head *net_exit_list);
 298         unsigned int *id;
 299         size_t size;
 300 };
 301
 302 /*
 303  * Use these carefully.  If you implement a network device and it
 304  * needs per network namespace operations use device pernet operations,
 305  * otherwise use pernet subsys operations.
 306  *
 307  * Network interfaces need to be removed from a dying netns _before_
 308  * subsys notifiers can be called, as most of the network code cleanup
 309  * (which is done from subsys notifiers) runs with the assumption that
 310  * dev_remove_pack has been called so no new packets will arrive during
 311  * and after the cleanup functions have been called.  dev_remove_pack
 312  * is not per namespace so instead the guarantee of no more packets
 313  * arriving in a network namespace is provided by ensuring that all
 314  * network devices and all sockets have left the network namespace
 315  * before the cleanup methods are called.
 316  *
 317  * For the longest time the ipv4 icmp code was registered as a pernet
 318  * device which caused kernel oops, and panics during network
 319  * namespace cleanup.   So please don't get this wrong.
 320  */
 321 int register_pernet_subsys(struct pernet_operations *);
 322 void unregister_pernet_subsys(struct pernet_operations *);
 323 int register_pernet_device(struct pernet_operations *);
 324 void unregister_pernet_device(struct pernet_operations *);
 325
 326 struct ctl_table;
 327 struct ctl_table_header;
 328
 329 #ifdef CONFIG_SYSCTL
 330 int net_sysctl_init(void);
 331 struct ctl_table_header *register_net_sysctl(struct net *net, const char *path,
 332                                              struct ctl_table *table);
 333 void unregister_net_sysctl_table(struct ctl_table_header *header);
 334 #else
 335 static inline int net_sysctl_init(void) { return 0; }
 336 static inline struct ctl_table_header *register_net_sysctl(struct net *net,
 337         const char *path, struct ctl_table *table)
 338 {
 339         return NULL;
 340 }
 341 static inline void unregister_net_sysctl_table(struct ctl_table_header *header)
 342 {
 343 }
 344 #endif
 345
 346 static inline int rt_genid_ipv4(struct net *net)
 347 {
 348         return atomic_read(&net->ipv4.rt_genid);
 349 }
 350
 351 static inline void rt_genid_bump_ipv4(struct net *net)
 352 {
 353         atomic_inc(&net->ipv4.rt_genid);
 354 }
 355
 356 extern void (*__fib6_flush_trees)(struct net *net);
 357 static inline void rt_genid_bump_ipv6(struct net *net)
 358 {
 359         if (__fib6_flush_trees)
 360                 __fib6_flush_trees(net);
 361 }
 362
 363 #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
 364 static inline struct netns_ieee802154_lowpan *
 365 net_ieee802154_lowpan(struct net *net)
 366 {
 367         return &net->ieee802154_lowpan;
 368 }
 369 #endif
 370
 371 /* For callers who don't really care about whether it's IPv4 or IPv6 */
 372 static inline void rt_genid_bump_all(struct net *net)
 373 {
 374         rt_genid_bump_ipv4(net);
 375         rt_genid_bump_ipv6(net);
 376 }
 377
 378 static inline int fnhe_genid(struct net *net)
 379 {
 380         return atomic_read(&net->fnhe_genid);
 381 }
 382
 383 static inline void fnhe_genid_bump(struct net *net)
 384 {
 385         atomic_inc(&net->fnhe_genid);
 386 }
 387
 388 #endif /* __NET_NET_NAMESPACE_H */