diff options
Diffstat (limited to 'include/net/net_namespace.h')
| -rw-r--r-- | include/net/net_namespace.h | 530 |
1 files changed, 530 insertions, 0 deletions
diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h new file mode 100644 index 000000000..8c3587d5c --- /dev/null +++ b/include/net/net_namespace.h @@ -0,0 +1,530 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Operations on the network namespace + */ +#ifndef __NET_NET_NAMESPACE_H +#define __NET_NET_NAMESPACE_H + +#include <linux/atomic.h> +#include <linux/refcount.h> +#include <linux/workqueue.h> +#include <linux/list.h> +#include <linux/sysctl.h> +#include <linux/uidgid.h> + +#include <net/flow.h> +#include <net/netns/core.h> +#include <net/netns/mib.h> +#include <net/netns/unix.h> +#include <net/netns/packet.h> +#include <net/netns/ipv4.h> +#include <net/netns/ipv6.h> +#include <net/netns/nexthop.h> +#include <net/netns/ieee802154_6lowpan.h> +#include <net/netns/sctp.h> +#include <net/netns/netfilter.h> +#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) +#include <net/netns/conntrack.h> +#endif +#if IS_ENABLED(CONFIG_NF_FLOW_TABLE) +#include <net/netns/flow_table.h> +#endif +#include <net/netns/nftables.h> +#include <net/netns/xfrm.h> +#include <net/netns/mpls.h> +#include <net/netns/can.h> +#include <net/netns/xdp.h> +#include <net/netns/smc.h> +#include <net/netns/bpf.h> +#include <net/netns/mctp.h> +#include <net/net_trackers.h> +#include <linux/ns_common.h> +#include <linux/idr.h> +#include <linux/skbuff.h> +#include <linux/notifier.h> + +struct user_namespace; +struct proc_dir_entry; +struct net_device; +struct sock; +struct ctl_table_header; +struct net_generic; +struct uevent_sock; +struct netns_ipvs; +struct bpf_prog; + + +#define NETDEV_HASHBITS 8 +#define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS) + +struct net { + /* First cache line can be often dirtied. + * Do not place here read-mostly fields. + */ + refcount_t passive; /* To decide when the network + * namespace should be freed. + */ + spinlock_t rules_mod_lock; + + atomic_t dev_unreg_count; + + unsigned int dev_base_seq; /* protected by rtnl_mutex */ + int ifindex; + + spinlock_t nsid_lock; + atomic_t fnhe_genid; + + struct list_head list; /* list of network namespaces */ + struct list_head exit_list; /* To linked to call pernet exit + * methods on dead net ( + * pernet_ops_rwsem read locked), + * or to unregister pernet ops + * (pernet_ops_rwsem write locked). + */ + struct llist_node cleanup_list; /* namespaces on death row */ + +#ifdef CONFIG_KEYS + struct key_tag *key_domain; /* Key domain of operation tag */ +#endif + struct user_namespace *user_ns; /* Owning user namespace */ + struct ucounts *ucounts; + struct idr netns_ids; + + struct ns_common ns; + struct ref_tracker_dir refcnt_tracker; + + struct list_head dev_base_head; + struct proc_dir_entry *proc_net; + struct proc_dir_entry *proc_net_stat; + +#ifdef CONFIG_SYSCTL + struct ctl_table_set sysctls; +#endif + + struct sock *rtnl; /* rtnetlink socket */ + struct sock *genl_sock; + + struct uevent_sock *uevent_sock; /* uevent socket */ + + struct hlist_head *dev_name_head; + struct hlist_head *dev_index_head; + struct raw_notifier_head netdev_chain; + + /* Note that @hash_mix can be read millions times per second, + * it is critical that it is on a read_mostly cache line. + */ + u32 hash_mix; + + struct net_device *loopback_dev; /* The loopback */ + + /* core fib_rules */ + struct list_head rules_ops; + + struct netns_core core; + struct netns_mib mib; + struct netns_packet packet; +#if IS_ENABLED(CONFIG_UNIX) + struct netns_unix unx; +#endif + struct netns_nexthop nexthop; + struct netns_ipv4 ipv4; +#if IS_ENABLED(CONFIG_IPV6) + struct netns_ipv6 ipv6; +#endif +#if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN) + struct netns_ieee802154_lowpan ieee802154_lowpan; +#endif +#if defined(CONFIG_IP_SCTP) || defined(CONFIG_IP_SCTP_MODULE) + struct netns_sctp sctp; +#endif +#ifdef CONFIG_NETFILTER + struct netns_nf nf; +#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) + struct netns_ct ct; +#endif +#if defined(CONFIG_NF_TABLES) || defined(CONFIG_NF_TABLES_MODULE) + struct netns_nftables nft; +#endif +#if IS_ENABLED(CONFIG_NF_FLOW_TABLE) + struct netns_ft ft; +#endif +#endif +#ifdef CONFIG_WEXT_CORE + struct sk_buff_head wext_nlevents; +#endif + struct net_generic __rcu *gen; + + /* Used to store attached BPF programs */ + struct netns_bpf bpf; + + /* Note : following structs are cache line aligned */ +#ifdef CONFIG_XFRM + struct netns_xfrm xfrm; +#endif + + u64 net_cookie; /* written once */ + +#if IS_ENABLED(CONFIG_IP_VS) + struct netns_ipvs *ipvs; +#endif +#if IS_ENABLED(CONFIG_MPLS) + struct netns_mpls mpls; +#endif +#if IS_ENABLED(CONFIG_CAN) + struct netns_can can; +#endif +#ifdef CONFIG_XDP_SOCKETS + struct netns_xdp xdp; +#endif +#if IS_ENABLED(CONFIG_MCTP) + struct netns_mctp mctp; +#endif +#if IS_ENABLED(CONFIG_CRYPTO_USER) + struct sock *crypto_nlsk; +#endif + struct sock *diag_nlsk; +#if IS_ENABLED(CONFIG_SMC) + struct netns_smc smc; +#endif +} __randomize_layout; + +#include <linux/seq_file_net.h> + +/* Init's network namespace */ +extern struct net init_net; + +#ifdef CONFIG_NET_NS +struct net *copy_net_ns(unsigned long flags, struct user_namespace *user_ns, + struct net *old_net); + +void net_ns_get_ownership(const struct net *net, kuid_t *uid, kgid_t *gid); + +void net_ns_barrier(void); + +struct ns_common *get_net_ns(struct ns_common *ns); +struct net *get_net_ns_by_fd(int fd); +#else /* CONFIG_NET_NS */ +#include <linux/sched.h> +#include <linux/nsproxy.h> +static inline struct net *copy_net_ns(unsigned long flags, + struct user_namespace *user_ns, struct net *old_net) +{ + if (flags & CLONE_NEWNET) + return ERR_PTR(-EINVAL); + return old_net; +} + +static inline void net_ns_get_ownership(const struct net *net, + kuid_t *uid, kgid_t *gid) +{ + *uid = GLOBAL_ROOT_UID; + *gid = GLOBAL_ROOT_GID; +} + +static inline void net_ns_barrier(void) {} + +static inline struct ns_common *get_net_ns(struct ns_common *ns) +{ + return ERR_PTR(-EINVAL); +} + +static inline struct net *get_net_ns_by_fd(int fd) +{ + return ERR_PTR(-EINVAL); +} +#endif /* CONFIG_NET_NS */ + + +extern struct list_head net_namespace_list; + +struct net *get_net_ns_by_pid(pid_t pid); + +#ifdef CONFIG_SYSCTL +void ipx_register_sysctl(void); +void ipx_unregister_sysctl(void); +#else +#define ipx_register_sysctl() +#define ipx_unregister_sysctl() +#endif + +#ifdef CONFIG_NET_NS +void __put_net(struct net *net); + +/* Try using get_net_track() instead */ +static inline struct net *get_net(struct net *net) +{ + refcount_inc(&net->ns.count); + return net; +} + +static inline struct net *maybe_get_net(struct net *net) +{ + /* Used when we know struct net exists but we + * aren't guaranteed a previous reference count + * exists. If the reference count is zero this + * function fails and returns NULL. + */ + if (!refcount_inc_not_zero(&net->ns.count)) + net = NULL; + return net; +} + +/* Try using put_net_track() instead */ +static inline void put_net(struct net *net) +{ + if (refcount_dec_and_test(&net->ns.count)) + __put_net(net); +} + +static inline +int net_eq(const struct net *net1, const struct net *net2) +{ + return net1 == net2; +} + +static inline int check_net(const struct net *net) +{ + return refcount_read(&net->ns.count) != 0; +} + +void net_drop_ns(void *); + +#else + +static inline struct net *get_net(struct net *net) +{ + return net; +} + +static inline void put_net(struct net *net) +{ +} + +static inline struct net *maybe_get_net(struct net *net) +{ + return net; +} + +static inline +int net_eq(const struct net *net1, const struct net *net2) +{ + return 1; +} + +static inline int check_net(const struct net *net) +{ + return 1; +} + +#define net_drop_ns NULL +#endif + + +static inline void netns_tracker_alloc(struct net *net, + netns_tracker *tracker, gfp_t gfp) +{ +#ifdef CONFIG_NET_NS_REFCNT_TRACKER + ref_tracker_alloc(&net->refcnt_tracker, tracker, gfp); +#endif +} + +static inline void netns_tracker_free(struct net *net, + netns_tracker *tracker) +{ +#ifdef CONFIG_NET_NS_REFCNT_TRACKER + ref_tracker_free(&net->refcnt_tracker, tracker); +#endif +} + +static inline struct net *get_net_track(struct net *net, + netns_tracker *tracker, gfp_t gfp) +{ + get_net(net); + netns_tracker_alloc(net, tracker, gfp); + return net; +} + +static inline void put_net_track(struct net *net, netns_tracker *tracker) +{ + netns_tracker_free(net, tracker); + put_net(net); +} + +typedef struct { +#ifdef CONFIG_NET_NS + struct net *net; +#endif +} possible_net_t; + +static inline void write_pnet(possible_net_t *pnet, struct net *net) +{ +#ifdef CONFIG_NET_NS + pnet->net = net; +#endif +} + +static inline struct net *read_pnet(const possible_net_t *pnet) +{ +#ifdef CONFIG_NET_NS + return pnet->net; +#else + return &init_net; +#endif +} + +/* Protected by net_rwsem */ +#define for_each_net(VAR) \ + list_for_each_entry(VAR, &net_namespace_list, list) +#define for_each_net_continue_reverse(VAR) \ + list_for_each_entry_continue_reverse(VAR, &net_namespace_list, list) +#define for_each_net_rcu(VAR) \ + list_for_each_entry_rcu(VAR, &net_namespace_list, list) + +#ifdef CONFIG_NET_NS +#define __net_init +#define __net_exit +#define __net_initdata +#define __net_initconst +#else +#define __net_init __init +#define __net_exit __ref +#define __net_initdata __initdata +#define __net_initconst __initconst +#endif + +int peernet2id_alloc(struct net *net, struct net *peer, gfp_t gfp); +int peernet2id(const struct net *net, struct net *peer); +bool peernet_has_id(const struct net *net, struct net *peer); +struct net *get_net_ns_by_id(const struct net *net, int id); + +struct pernet_operations { + struct list_head list; + /* + * Below methods are called without any exclusive locks. + * More than one net may be constructed and destructed + * in parallel on several cpus. Every pernet_operations + * have to keep in mind all other pernet_operations and + * to introduce a locking, if they share common resources. + * + * The only time they are called with exclusive lock is + * from register_pernet_subsys(), unregister_pernet_subsys() + * register_pernet_device() and unregister_pernet_device(). + * + * Exit methods using blocking RCU primitives, such as + * synchronize_rcu(), should be implemented via exit_batch. + * Then, destruction of a group of net requires single + * synchronize_rcu() related to these pernet_operations, + * instead of separate synchronize_rcu() for every net. + * Please, avoid synchronize_rcu() at all, where it's possible. + * + * Note that a combination of pre_exit() and exit() can + * be used, since a synchronize_rcu() is guaranteed between + * the calls. + */ + int (*init)(struct net *net); + void (*pre_exit)(struct net *net); + void (*exit)(struct net *net); + void (*exit_batch)(struct list_head *net_exit_list); + unsigned int *id; + size_t size; +}; + +/* + * Use these carefully. If you implement a network device and it + * needs per network namespace operations use device pernet operations, + * otherwise use pernet subsys operations. + * + * Network interfaces need to be removed from a dying netns _before_ + * subsys notifiers can be called, as most of the network code cleanup + * (which is done from subsys notifiers) runs with the assumption that + * dev_remove_pack has been called so no new packets will arrive during + * and after the cleanup functions have been called. dev_remove_pack + * is not per namespace so instead the guarantee of no more packets + * arriving in a network namespace is provided by ensuring that all + * network devices and all sockets have left the network namespace + * before the cleanup methods are called. + * + * For the longest time the ipv4 icmp code was registered as a pernet + * device which caused kernel oops, and panics during network + * namespace cleanup. So please don't get this wrong. + */ +int register_pernet_subsys(struct pernet_operations *); +void unregister_pernet_subsys(struct pernet_operations *); +int register_pernet_device(struct pernet_operations *); +void unregister_pernet_device(struct pernet_operations *); + +struct ctl_table; + +#ifdef CONFIG_SYSCTL +int net_sysctl_init(void); +struct ctl_table_header *register_net_sysctl(struct net *net, const char *path, + struct ctl_table *table); +void unregister_net_sysctl_table(struct ctl_table_header *header); +#else +static inline int net_sysctl_init(void) { return 0; } +static inline struct ctl_table_header *register_net_sysctl(struct net *net, + const char *path, struct ctl_table *table) +{ + return NULL; +} +static inline void unregister_net_sysctl_table(struct ctl_table_header *header) +{ +} +#endif + +static inline int rt_genid_ipv4(const struct net *net) +{ + return atomic_read(&net->ipv4.rt_genid); +} + +#if IS_ENABLED(CONFIG_IPV6) +static inline int rt_genid_ipv6(const struct net *net) +{ + return atomic_read(&net->ipv6.fib6_sernum); +} +#endif + +static inline void rt_genid_bump_ipv4(struct net *net) +{ + atomic_inc(&net->ipv4.rt_genid); +} + +extern void (*__fib6_flush_trees)(struct net *net); +static inline void rt_genid_bump_ipv6(struct net *net) +{ + if (__fib6_flush_trees) + __fib6_flush_trees(net); +} + +#if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN) +static inline struct netns_ieee802154_lowpan * +net_ieee802154_lowpan(struct net *net) +{ + return &net->ieee802154_lowpan; +} +#endif + +/* For callers who don't really care about whether it's IPv4 or IPv6 */ +static inline void rt_genid_bump_all(struct net *net) +{ + rt_genid_bump_ipv4(net); + rt_genid_bump_ipv6(net); +} + +static inline int fnhe_genid(const struct net *net) +{ + return atomic_read(&net->fnhe_genid); +} + +static inline void fnhe_genid_bump(struct net *net) +{ + atomic_inc(&net->fnhe_genid); +} + +#ifdef CONFIG_NET +void net_ns_init(void); +#else +static inline void net_ns_init(void) {} +#endif + +#endif /* __NET_NET_NAMESPACE_H */ |