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