Edit File: sock.h
/* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket * interface as the means of communication with the user level. * * Definitions for the AF_INET socket handler. * * Version: @(#)sock.h 1.0.4 05/13/93 * * Authors: Ross Biro * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> * Corey Minyard <wf-rch!minyard@relay.EU.net> * Florian La Roche <flla@stud.uni-sb.de> * * Fixes: * Alan Cox : Volatiles in skbuff pointers. See * skbuff comments. May be overdone, * better to prove they can be removed * than the reverse. * Alan Cox : Added a zapped field for tcp to note * a socket is reset and must stay shut up * Alan Cox : New fields for options * Pauline Middelink : identd support * Alan Cox : Eliminate low level recv/recvfrom * David S. Miller : New socket lookup architecture. * Steve Whitehouse: Default routines for sock_ops * Arnaldo C. Melo : removed net_pinfo, tp_pinfo and made * protinfo be just a void pointer, as the * protocol specific parts were moved to * respective headers and ipv4/v6, etc now * use private slabcaches for its socks * Pedro Hortas : New flags field for socket options * * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ #ifndef _SOCK_H #define _SOCK_H #include <linux/hardirq.h> #include <linux/kernel.h> #include <linux/list.h> #include <linux/list_nulls.h> #include <linux/timer.h> #include <linux/cache.h> #include <linux/bitops.h> #include <linux/lockdep.h> #include <linux/netdevice.h> #include <linux/skbuff.h> /* struct sk_buff */ #include <linux/mm.h> #include <linux/security.h> #include <linux/slab.h> #include <linux/uaccess.h> #ifdef __GENKSYMS__ #include <linux/res_counter.h> #else #include <linux/page_counter.h> #endif #include <linux/memcontrol.h> #include <linux/static_key.h> #include <linux/aio.h> #include <linux/sched.h> #include <linux/filter.h> #include <linux/rculist_nulls.h> #include <linux/poll.h> #include <linux/atomic.h> #include <net/dst.h> #include <net/checksum.h> #include <linux/net_tstamp.h> #include <linux/rh_kabi.h> #include <net/tcp_states.h> struct cgroup; struct cgroup_subsys; #ifdef CONFIG_NET int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss); void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg); #else static inline int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss) { return 0; } static inline void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg) { } #endif /* * This structure really needs to be cleaned up. * Most of it is for TCP, and not used by any of * the other protocols. */ /* Define this to get the SOCK_DBG debugging facility. */ #define SOCK_DEBUGGING #ifdef SOCK_DEBUGGING #define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \ printk(KERN_DEBUG msg); } while (0) #else /* Validate arguments and do nothing */ static inline __printf(2, 3) void SOCK_DEBUG(const struct sock *sk, const char *msg, ...) { } #endif /* This is the per-socket lock. The spinlock provides a synchronization * between user contexts and software interrupt processing, whereas the * mini-semaphore synchronizes multiple users amongst themselves. */ typedef struct { spinlock_t slock; int owned; wait_queue_head_t wq; /* * We express the mutex-alike socket_lock semantics * to the lock validator by explicitly managing * the slock as a lock variant (in addition to * the slock itself): */ #ifdef CONFIG_DEBUG_LOCK_ALLOC struct lockdep_map dep_map; #endif } socket_lock_t; struct sock; struct proto; struct net; typedef __u32 __bitwise __portpair; typedef __u64 __bitwise __addrpair; /** * struct sock_common - minimal network layer representation of sockets * @skc_daddr: Foreign IPv4 addr * @skc_rcv_saddr: Bound local IPv4 addr * @skc_hash: hash value used with various protocol lookup tables * @skc_u16hashes: two u16 hash values used by UDP lookup tables * @skc_dport: placeholder for inet_dport/tw_dport * @skc_num: placeholder for inet_num/tw_num * @skc_family: network address family * @skc_state: Connection state * @skc_reuse: %SO_REUSEADDR setting * @skc_reuseport: %SO_REUSEPORT setting * @skc_bound_dev_if: bound device index if != 0 * @skc_bind_node: bind hash linkage for various protocol lookup tables * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol * @skc_prot: protocol handlers inside a network family * @skc_net: reference to the network namespace of this socket * @skc_node: main hash linkage for various protocol lookup tables * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol * @skc_tx_queue_mapping: tx queue number for this connection * @skc_refcnt: reference count * * This is the minimal network layer representation of sockets, the header * for struct sock and struct inet_timewait_sock. */ struct sock_common { /* skc_daddr and skc_rcv_saddr must be grouped on a 8 bytes aligned * address on 64bit arches : cf INET_MATCH() */ union { __addrpair skc_addrpair; struct { __be32 skc_daddr; __be32 skc_rcv_saddr; }; }; union { unsigned int skc_hash; __u16 skc_u16hashes[2]; }; /* skc_dport && skc_num must be grouped as well */ union { __portpair skc_portpair; struct { __be16 skc_dport; __u16 skc_num; }; }; unsigned short skc_family; volatile unsigned char skc_state; unsigned char skc_reuse:4; unsigned char skc_reuseport:4; int skc_bound_dev_if; union { struct hlist_node skc_bind_node; RH_KABI_REPLACE(struct hlist_nulls_node skc_portaddr_node, struct hlist_node skc_portaddr_node) }; struct proto *skc_prot; possible_net_t skc_net; #if IS_ENABLED(CONFIG_IPV6) struct in6_addr skc_v6_daddr; struct in6_addr skc_v6_rcv_saddr; #endif /* * fields between dontcopy_begin/dontcopy_end * are not copied in sock_copy() */ /* private: */ int skc_dontcopy_begin[0]; /* public: */ union { struct hlist_node skc_node; struct hlist_nulls_node skc_nulls_node; }; int skc_tx_queue_mapping; atomic_t skc_refcnt; /* private: */ int skc_dontcopy_end[0]; /* public: */ }; struct cg_proto; /** * struct sock - network layer representation of sockets * @__sk_common: shared layout with inet_timewait_sock * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings * @sk_lock: synchronizer * @sk_rcvbuf: size of receive buffer in bytes * @sk_wq: sock wait queue and async head * @sk_rx_dst: receive input route used by early demux * @sk_dst_cache: destination cache * @sk_dst_pending_confirm: need to confirm neighbour * @sk_policy: flow policy * @sk_receive_queue: incoming packets * @sk_wmem_alloc: transmit queue bytes committed * @sk_write_queue: Packet sending queue * @sk_omem_alloc: "o" is "option" or "other" * @sk_wmem_queued: persistent queue size * @sk_forward_alloc: space allocated forward * @sk_napi_id: id of the last napi context to receive data for sk * @sk_ll_usec: usecs to busypoll when there is no data * @sk_allocation: allocation mode * @sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler) * @sk_sndbuf: size of send buffer in bytes * @sk_flags: %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE, * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings * @sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets * @sk_no_check_rx: allow zero checksum in RX packets * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO) * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK) * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4) * @sk_gso_max_size: Maximum GSO segment size to build * @sk_gso_max_segs: Maximum number of GSO segments * @sk_lingertime: %SO_LINGER l_linger setting * @sk_backlog: always used with the per-socket spinlock held * @sk_callback_lock: used with the callbacks in the end of this struct * @sk_error_queue: rarely used * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt, * IPV6_ADDRFORM for instance) * @sk_err: last error * @sk_err_soft: errors that don't cause failure but are the cause of a * persistent failure not just 'timed out' * @sk_drops: raw/udp drops counter * @sk_ack_backlog: current listen backlog * @sk_max_ack_backlog: listen backlog set in listen() * @sk_priority: %SO_PRIORITY setting * @sk_cgrp_prioidx: socket group's priority map index * @sk_type: socket type (%SOCK_STREAM, etc) * @sk_protocol: which protocol this socket belongs in this network family * @sk_peer_pid: &struct pid for this socket's peer * @sk_peer_cred: %SO_PEERCRED setting * @sk_rcvlowat: %SO_RCVLOWAT setting * @sk_rcvtimeo: %SO_RCVTIMEO setting * @sk_sndtimeo: %SO_SNDTIMEO setting * @sk_rxhash: flow hash received from netif layer * @sk_txhash: computed flow hash for use on transmit * @sk_filter: socket filtering instructions * @sk_protinfo: private area, net family specific, when not using slab * @sk_timer: sock cleanup timer * @sk_stamp: time stamp of last packet received * @sk_tsflags: SO_TIMESTAMPING socket options * @sk_socket: Identd and reporting IO signals * @sk_user_data: RPC layer private data * @sk_frag: cached page frag * @sk_peek_off: current peek_offset value * @sk_send_head: front of stuff to transmit * @sk_security: used by security modules * @sk_mark: generic packet mark * @sk_classid: this socket's cgroup classid * @sk_cgrp: this socket's cgroup-specific proto data * @sk_write_pending: a write to stream socket waits to start * @sk_state_change: callback to indicate change in the state of the sock * @sk_data_ready: callback to indicate there is data to be processed * @sk_write_space: callback to indicate there is bf sending space available * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE) * @sk_backlog_rcv: callback to process the backlog * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0 * @sk_reuseport_cb: reuseport group container */ struct sock { /* * Now struct inet_timewait_sock also uses sock_common, so please just * don't add nothing before this first member (__sk_common) --acme */ struct sock_common __sk_common; #define sk_node __sk_common.skc_node #define sk_nulls_node __sk_common.skc_nulls_node #define sk_refcnt __sk_common.skc_refcnt #define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping #define sk_dontcopy_begin __sk_common.skc_dontcopy_begin #define sk_dontcopy_end __sk_common.skc_dontcopy_end #define sk_hash __sk_common.skc_hash #define sk_portpair __sk_common.skc_portpair #define sk_num __sk_common.skc_num #define sk_dport __sk_common.skc_dport #define sk_addrpair __sk_common.skc_addrpair #define sk_daddr __sk_common.skc_daddr #define sk_rcv_saddr __sk_common.skc_rcv_saddr #define sk_family __sk_common.skc_family #define sk_state __sk_common.skc_state #define sk_reuse __sk_common.skc_reuse #define sk_reuseport __sk_common.skc_reuseport #define sk_bound_dev_if __sk_common.skc_bound_dev_if #define sk_bind_node __sk_common.skc_bind_node #define sk_prot __sk_common.skc_prot #define sk_net __sk_common.skc_net #define sk_v6_daddr __sk_common.skc_v6_daddr #define sk_v6_rcv_saddr __sk_common.skc_v6_rcv_saddr socket_lock_t sk_lock; struct sk_buff_head sk_receive_queue; /* * The backlog queue is special, it is always used with * the per-socket spinlock held and requires low latency * access. Therefore we special case it's implementation. * Note : rmem_alloc is in this structure to fill a hole * on 64bit arches, not because its logically part of * backlog. */ struct { atomic_t rmem_alloc; int len; struct sk_buff *head; struct sk_buff *tail; } sk_backlog; #define sk_rmem_alloc sk_backlog.rmem_alloc int sk_forward_alloc; #ifdef CONFIG_RPS __u32 sk_rxhash; #endif #ifdef CONFIG_NET_RX_BUSY_POLL unsigned int sk_napi_id; unsigned int sk_ll_usec; #endif atomic_t sk_drops; int sk_rcvbuf; struct sk_filter __rcu *sk_filter; struct socket_wq __rcu *sk_wq; #ifdef CONFIG_NET_DMA_RH_KABI RH_KABI_DEPRECATE(struct sk_buff_head, sk_async_wait_queue) #endif #ifdef CONFIG_XFRM struct xfrm_policy *sk_policy[2]; #endif unsigned long sk_flags; struct dst_entry *sk_rx_dst; struct dst_entry __rcu *sk_dst_cache; RH_KABI_DEPRECATE(spinlock_t, sk_dst_lock) atomic_t sk_wmem_alloc; atomic_t sk_omem_alloc; int sk_sndbuf; struct sk_buff_head sk_write_queue; kmemcheck_bitfield_begin(flags); unsigned int sk_shutdown : 2, #ifdef __GENKSYMS__ sk_no_check : 2, #else sk_no_check_tx : 1, sk_no_check_rx : 1, #endif sk_userlocks : 4, sk_protocol : 8, #define SK_PROTOCOL_MAX U8_MAX sk_type : 16; kmemcheck_bitfield_end(flags); int sk_wmem_queued; gfp_t sk_allocation; u32 sk_pacing_rate; /* bytes per second */ netdev_features_t sk_route_caps; netdev_features_t sk_route_nocaps; int sk_gso_type; unsigned int sk_gso_max_size; u16 sk_gso_max_segs; int sk_rcvlowat; unsigned long sk_lingertime; struct sk_buff_head sk_error_queue; struct proto *sk_prot_creator; rwlock_t sk_callback_lock; int sk_err, sk_err_soft; unsigned short sk_ack_backlog; unsigned short sk_max_ack_backlog; __u32 sk_priority; #if IS_ENABLED(CONFIG_NETPRIO_CGROUP) __u32 sk_cgrp_prioidx; #endif struct pid *sk_peer_pid; const struct cred *sk_peer_cred; long sk_rcvtimeo; long sk_sndtimeo; void *sk_protinfo; struct timer_list sk_timer; ktime_t sk_stamp; struct socket *sk_socket; void *sk_user_data; struct page_frag sk_frag; struct sk_buff *sk_send_head; __s32 sk_peek_off; int sk_write_pending; #ifdef CONFIG_SECURITY void *sk_security; #endif __u32 sk_mark; u32 sk_classid; struct cg_proto *sk_cgrp; void (*sk_state_change)(struct sock *sk); void (*sk_data_ready)(struct sock *sk, int bytes); void (*sk_write_space)(struct sock *sk); void (*sk_error_report)(struct sock *sk); int (*sk_backlog_rcv)(struct sock *sk, struct sk_buff *skb); void (*sk_destruct)(struct sock *sk); /* RHEL SPECIFIC * * The following padding has been inserted before ABI freeze to * allow extending the structure while preserve ABI. Feel free * to replace reserved slots with required structure field * additions of your backport. */ RH_KABI_USE2_P(1, __u32 sk_txhash, u32 sk_max_pacing_rate) RH_KABI_USE2_P(2, u16 sk_tsflags, __u32 sk_dst_pending_confirm) RH_KABI_USE_P(3, struct sock_reuseport __rcu *sk_reuseport_cb) #ifndef __GENKSYMS__ struct rcu_head sk_rcu; #else RH_KABI_USE_P(4, sk_rcu.next) RH_KABI_USE_P(5, sk_rcu.func) #endif RH_KABI_RESERVE_P(6) RH_KABI_RESERVE_P(7) RH_KABI_RESERVE_P(8) }; #define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data))) #define rcu_dereference_sk_user_data(sk) rcu_dereference(__sk_user_data((sk))) #define rcu_assign_sk_user_data(sk, ptr) rcu_assign_pointer(__sk_user_data((sk)), ptr) /* * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK * or not whether his port will be reused by someone else. SK_FORCE_REUSE * on a socket means that the socket will reuse everybody else's port * without looking at the other's sk_reuse value. */ #define SK_NO_REUSE 0 #define SK_CAN_REUSE 1 #define SK_FORCE_REUSE 2 static inline int sk_peek_offset(struct sock *sk, int flags) { if (unlikely(flags & MSG_PEEK)) { s32 off = READ_ONCE(sk->sk_peek_off); if (off >= 0) return off; } return 0; } static inline void sk_peek_offset_bwd(struct sock *sk, int val) { s32 off = READ_ONCE(sk->sk_peek_off); if (unlikely(off >= 0)) { off = max_t(s32, off - val, 0); WRITE_ONCE(sk->sk_peek_off, off); } } static inline void sk_peek_offset_fwd(struct sock *sk, int val) { sk_peek_offset_bwd(sk, -val); } /* * Hashed lists helper routines */ static inline struct sock *sk_entry(const struct hlist_node *node) { return hlist_entry(node, struct sock, sk_node); } static inline struct sock *__sk_head(const struct hlist_head *head) { return hlist_entry(head->first, struct sock, sk_node); } static inline struct sock *sk_head(const struct hlist_head *head) { return hlist_empty(head) ? NULL : __sk_head(head); } static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head) { return hlist_nulls_entry(head->first, struct sock, sk_nulls_node); } static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head) { return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head); } static inline struct sock *sk_next(const struct sock *sk) { return sk->sk_node.next ? hlist_entry(sk->sk_node.next, struct sock, sk_node) : NULL; } static inline struct sock *sk_nulls_next(const struct sock *sk) { return (!is_a_nulls(sk->sk_nulls_node.next)) ? hlist_nulls_entry(sk->sk_nulls_node.next, struct sock, sk_nulls_node) : NULL; } static inline bool sk_unhashed(const struct sock *sk) { return hlist_unhashed(&sk->sk_node); } static inline bool sk_hashed(const struct sock *sk) { return !sk_unhashed(sk); } static inline void sk_node_init(struct hlist_node *node) { node->pprev = NULL; } static inline void sk_nulls_node_init(struct hlist_nulls_node *node) { node->pprev = NULL; } static inline void __sk_del_node(struct sock *sk) { __hlist_del(&sk->sk_node); } /* NB: equivalent to hlist_del_init_rcu */ static inline bool __sk_del_node_init(struct sock *sk) { if (sk_hashed(sk)) { __sk_del_node(sk); sk_node_init(&sk->sk_node); return true; } return false; } /* Grab socket reference count. This operation is valid only when sk is ALREADY grabbed f.e. it is found in hash table or a list and the lookup is made under lock preventing hash table modifications. */ static inline void sock_hold(struct sock *sk) { atomic_inc(&sk->sk_refcnt); } /* Ungrab socket in the context, which assumes that socket refcnt cannot hit zero, f.e. it is true in context of any socketcall. */ static inline void __sock_put(struct sock *sk) { atomic_dec(&sk->sk_refcnt); } static inline bool sk_del_node_init(struct sock *sk) { bool rc = __sk_del_node_init(sk); if (rc) { /* paranoid for a while -acme */ WARN_ON(atomic_read(&sk->sk_refcnt) == 1); __sock_put(sk); } return rc; } #define sk_del_node_init_rcu(sk) sk_del_node_init(sk) static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk) { if (sk_hashed(sk)) { hlist_nulls_del_init_rcu(&sk->sk_nulls_node); return true; } return false; } static inline bool sk_nulls_del_node_init_rcu(struct sock *sk) { bool rc = __sk_nulls_del_node_init_rcu(sk); if (rc) { /* paranoid for a while -acme */ WARN_ON(atomic_read(&sk->sk_refcnt) == 1); __sock_put(sk); } return rc; } static inline void __sk_add_node(struct sock *sk, struct hlist_head *list) { hlist_add_head(&sk->sk_node, list); } static inline void sk_add_node(struct sock *sk, struct hlist_head *list) { sock_hold(sk); __sk_add_node(sk, list); } static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list) { sock_hold(sk); if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport && sk->sk_family == AF_INET6) hlist_add_tail_rcu(&sk->sk_node, list); else hlist_add_head_rcu(&sk->sk_node, list); } static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list) { if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport && sk->sk_family == AF_INET6) hlist_nulls_add_tail_rcu(&sk->sk_nulls_node, list); else hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list); } static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list) { sock_hold(sk); __sk_nulls_add_node_rcu(sk, list); } static inline void __sk_del_bind_node(struct sock *sk) { __hlist_del(&sk->sk_bind_node); } static inline void sk_add_bind_node(struct sock *sk, struct hlist_head *list) { hlist_add_head(&sk->sk_bind_node, list); } #define sk_for_each(__sk, list) \ hlist_for_each_entry(__sk, list, sk_node) #define sk_for_each_rcu(__sk, list) \ hlist_for_each_entry_rcu(__sk, list, sk_node) #define sk_nulls_for_each(__sk, node, list) \ hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node) #define sk_nulls_for_each_rcu(__sk, node, list) \ hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node) #define sk_for_each_from(__sk) \ hlist_for_each_entry_from(__sk, sk_node) #define sk_nulls_for_each_from(__sk, node) \ if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \ hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node) #define sk_for_each_safe(__sk, tmp, list) \ hlist_for_each_entry_safe(__sk, tmp, list, sk_node) #define sk_for_each_bound(__sk, list) \ hlist_for_each_entry(__sk, list, sk_bind_node) /** * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset * @tpos: the type * to use as a loop cursor. * @pos: the &struct hlist_node to use as a loop cursor. * @head: the head for your list. * @offset: offset of hlist_node within the struct. * */ #define sk_for_each_entry_offset_rcu(tpos, pos, head, offset) \ for (pos = rcu_dereference((head)->first); \ pos != NULL && \ ({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \ pos = rcu_dereference(pos->next)) static inline struct user_namespace *sk_user_ns(struct sock *sk) { /* Careful only use this in a context where these parameters * can not change and must all be valid, such as recvmsg from * userspace. */ return sk->sk_socket->file->f_cred->user_ns; } /* Sock flags */ enum sock_flags { SOCK_DEAD, SOCK_DONE, SOCK_URGINLINE, SOCK_KEEPOPEN, SOCK_LINGER, SOCK_DESTROY, SOCK_BROADCAST, SOCK_TIMESTAMP, SOCK_ZAPPED, SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */ SOCK_DBG, /* %SO_DEBUG setting */ SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */ SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */ SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */ SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */ SOCK_MEMALLOC, /* VM depends on this socket for swapping */ SOCK_RH_RESERVED_1, /* placeholders to avoid shifting the rest of * the SOCK_* flags */ SOCK_RH_RESERVED_2, SOCK_RH_RESERVED_3, SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */ SOCK_RH_RESERVED_4, SOCK_RH_RESERVED_5, SOCK_RH_RESERVED_6, SOCK_FASYNC, /* fasync() active */ SOCK_RXQ_OVFL, SOCK_ZEROCOPY, /* buffers from userspace */ SOCK_WIFI_STATUS, /* push wifi status to userspace */ SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS. * Will use last 4 bytes of packet sent from * user-space instead. */ SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */ SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */ SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */ }; #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)) static inline void sock_copy_flags(struct sock *nsk, struct sock *osk) { nsk->sk_flags = osk->sk_flags; } static inline void sock_set_flag(struct sock *sk, enum sock_flags flag) { __set_bit(flag, &sk->sk_flags); } static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag) { __clear_bit(flag, &sk->sk_flags); } static inline bool sock_flag(const struct sock *sk, enum sock_flags flag) { return test_bit(flag, &sk->sk_flags); } #ifdef CONFIG_NET extern struct static_key memalloc_socks; static inline int sk_memalloc_socks(void) { return static_key_false(&memalloc_socks); } #else static inline int sk_memalloc_socks(void) { return 0; } #endif static inline gfp_t sk_gfp_atomic(struct sock *sk, gfp_t gfp_mask) { return GFP_ATOMIC | (sk->sk_allocation & __GFP_MEMALLOC); } static inline void sk_acceptq_removed(struct sock *sk) { sk->sk_ack_backlog--; } static inline void sk_acceptq_added(struct sock *sk) { sk->sk_ack_backlog++; } static inline bool sk_acceptq_is_full(const struct sock *sk) { return sk->sk_ack_backlog > sk->sk_max_ack_backlog; } /* * Compute minimal free write space needed to queue new packets. */ static inline int sk_stream_min_wspace(const struct sock *sk) { return sk->sk_wmem_queued >> 1; } static inline int sk_stream_wspace(const struct sock *sk) { return sk->sk_sndbuf - sk->sk_wmem_queued; } extern void sk_stream_write_space(struct sock *sk); /* OOB backlog add */ static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb) { /* dont let skb dst not refcounted, we are going to leave rcu lock */ skb_dst_force_safe(skb); if (!sk->sk_backlog.tail) sk->sk_backlog.head = skb; else sk->sk_backlog.tail->next = skb; sk->sk_backlog.tail = skb; skb->next = NULL; } /* * Take into account size of receive queue and backlog queue * Do not take into account this skb truesize, * to allow even a single big packet to come. */ static inline bool sk_rcvqueues_full(const struct sock *sk, const struct sk_buff *skb, unsigned int limit) { unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc); return qsize > limit; } /* The per-socket spinlock must be held here. */ static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb, unsigned int limit) { if (sk_rcvqueues_full(sk, skb, limit)) return -ENOBUFS; /* * If the skb was allocated from pfmemalloc reserves, only * allow SOCK_MEMALLOC sockets to use it as this socket is * helping free memory */ if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) return -ENOMEM; __sk_add_backlog(sk, skb); sk->sk_backlog.len += skb->truesize; return 0; } extern int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb); static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) { if (sk_memalloc_socks() && skb_pfmemalloc(skb)) return __sk_backlog_rcv(sk, skb); return sk->sk_backlog_rcv(sk, skb); } static inline void sock_rps_record_flow(const struct sock *sk) { #ifdef CONFIG_RPS struct rps_sock_flow_table *sock_flow_table; rcu_read_lock(); sock_flow_table = rcu_dereference(rps_sock_flow_table); rps_record_sock_flow(sock_flow_table, sk->sk_rxhash); rcu_read_unlock(); #endif } static inline void sock_rps_reset_flow(const struct sock *sk) { #ifdef CONFIG_RPS struct rps_sock_flow_table *sock_flow_table; rcu_read_lock(); sock_flow_table = rcu_dereference(rps_sock_flow_table); rps_reset_sock_flow(sock_flow_table, sk->sk_rxhash); rcu_read_unlock(); #endif } static inline void sock_rps_save_rxhash(struct sock *sk, const struct sk_buff *skb) { #ifdef CONFIG_RPS if (unlikely(sk->sk_rxhash != skb->hash)) { sock_rps_reset_flow(sk); sk->sk_rxhash = skb->hash; } #endif } static inline void sock_rps_reset_rxhash(struct sock *sk) { #ifdef CONFIG_RPS sock_rps_reset_flow(sk); sk->sk_rxhash = 0; #endif } #define sk_wait_event(__sk, __timeo, __condition) \ ({ int __rc; \ release_sock(__sk); \ __rc = __condition; \ if (!__rc) { \ *(__timeo) = schedule_timeout(*(__timeo)); \ } \ lock_sock(__sk); \ __rc = __condition; \ __rc; \ }) extern int sk_stream_wait_connect(struct sock *sk, long *timeo_p); extern int sk_stream_wait_memory(struct sock *sk, long *timeo_p); extern void sk_stream_wait_close(struct sock *sk, long timeo_p); extern int sk_stream_error(struct sock *sk, int flags, int err); extern void sk_stream_kill_queues(struct sock *sk); extern void sk_set_memalloc(struct sock *sk); extern void sk_clear_memalloc(struct sock *sk); int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb); struct request_sock_ops; struct timewait_sock_ops; struct inet_hashinfo; struct raw_hashinfo; struct module; /* * caches using SLAB_DESTROY_BY_RCU should let .next pointer from nulls nodes * un-modified. Special care is taken when initializing object to zero. */ static inline void sk_prot_clear_nulls(struct sock *sk, int size) { if (offsetof(struct sock, sk_node.next) != 0) memset(sk, 0, offsetof(struct sock, sk_node.next)); memset(&sk->sk_node.pprev, 0, size - offsetof(struct sock, sk_node.pprev)); } /* Networking protocol blocks we attach to sockets. * socket layer -> transport layer interface * transport -> network interface is defined by struct inet_proto */ struct proto { void (*close)(struct sock *sk, long timeout); int (*connect)(struct sock *sk, struct sockaddr *uaddr, int addr_len); int (*disconnect)(struct sock *sk, int flags); struct sock * (*accept)(struct sock *sk, int flags, int *err); int (*ioctl)(struct sock *sk, int cmd, unsigned long arg); int (*init)(struct sock *sk); void (*destroy)(struct sock *sk); void (*shutdown)(struct sock *sk, int how); int (*setsockopt)(struct sock *sk, int level, int optname, char __user *optval, unsigned int optlen); int (*getsockopt)(struct sock *sk, int level, int optname, char __user *optval, int __user *option); #ifdef CONFIG_COMPAT int (*compat_setsockopt)(struct sock *sk, int level, int optname, char __user *optval, unsigned int optlen); int (*compat_getsockopt)(struct sock *sk, int level, int optname, char __user *optval, int __user *option); int (*compat_ioctl)(struct sock *sk, unsigned int cmd, unsigned long arg); #endif int (*sendmsg)(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, size_t len); int (*recvmsg)(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, size_t len, int noblock, int flags, int *addr_len); int (*sendpage)(struct sock *sk, struct page *page, int offset, size_t size, int flags); int (*bind)(struct sock *sk, struct sockaddr *uaddr, int addr_len); int (*backlog_rcv) (struct sock *sk, struct sk_buff *skb); void (*release_cb)(struct sock *sk); void (*mtu_reduced)(struct sock *sk); /* not used anymore */ /* Keeping track of sk's, looking them up, and port selection methods. */ void (*hash)(struct sock *sk); void (*unhash)(struct sock *sk); void (*rehash)(struct sock *sk); int (*get_port)(struct sock *sk, unsigned short snum); void (*clear_sk)(struct sock *sk, int size); /* Keeping track of sockets in use */ #ifdef CONFIG_PROC_FS unsigned int inuse_idx; #endif #ifndef __GENKSYMS__ bool (*stream_memory_free)(const struct sock *sk); #endif /* Memory pressure */ void (*enter_memory_pressure)(struct sock *sk); atomic_long_t *memory_allocated; /* Current allocated memory. */ struct percpu_counter *sockets_allocated; /* Current number of sockets. */ /* * Pressure flag: try to collapse. * Technical note: it is used by multiple contexts non atomically. * All the __sk_mem_schedule() is of this nature: accounting * is strict, actions are advisory and have some latency. */ int *memory_pressure; long *sysctl_mem; int *sysctl_wmem; int *sysctl_rmem; int max_header; bool no_autobind; struct kmem_cache *slab; unsigned int obj_size; int slab_flags; struct percpu_counter *orphan_count; struct request_sock_ops *rsk_prot; struct timewait_sock_ops *twsk_prot; union { struct inet_hashinfo *hashinfo; struct udp_table *udp_table; struct raw_hashinfo *raw_hash; } h; struct module *owner; char name[32]; struct list_head node; #ifdef SOCK_REFCNT_DEBUG atomic_t socks; #endif #ifdef CONFIG_MEMCG_KMEM /* * cgroup specific init/deinit functions. Called once for all * protocols that implement it, from cgroups populate function. * This function has to setup any files the protocol want to * appear in the kmem cgroup filesystem. */ int (*init_cgroup)(struct mem_cgroup *memcg, struct cgroup_subsys *ss); void (*destroy_cgroup)(struct mem_cgroup *memcg); struct cg_proto *(*proto_cgroup)(struct mem_cgroup *memcg); #endif }; /* * Bits in struct cg_proto.flags */ enum cg_proto_flags { /* Currently active and new sockets should be assigned to cgroups */ MEMCG_SOCK_ACTIVE, /* It was ever activated; we must disarm static keys on destruction */ MEMCG_SOCK_ACTIVATED, }; struct cg_proto { void (*enter_memory_pressure)(struct sock *sk); /* Current allocated memory. */ RH_KABI_REPLACE(struct res_counter *memory_allocated, struct page_counter *memory_allocated) RH_KABI_DEPRECATE(struct percpu_counter*, sockets_allocated) int *memory_pressure; long *sysctl_mem; unsigned long flags; /* * memcg field is used to find which memcg we belong directly * Each memcg struct can hold more than one cg_proto, so container_of * won't really cut. * * The elegant solution would be having an inverse function to * proto_cgroup in struct proto, but that means polluting the structure * for everybody, instead of just for memcg users. */ struct mem_cgroup *memcg; }; extern int proto_register(struct proto *prot, int alloc_slab); extern void proto_unregister(struct proto *prot); static inline bool memcg_proto_active(struct cg_proto *cg_proto) { return test_bit(MEMCG_SOCK_ACTIVE, &cg_proto->flags); } static inline bool memcg_proto_activated(struct cg_proto *cg_proto) { return test_bit(MEMCG_SOCK_ACTIVATED, &cg_proto->flags); } int sock_load_diag_module(int family, int protocol); #ifdef SOCK_REFCNT_DEBUG static inline void sk_refcnt_debug_inc(struct sock *sk) { atomic_inc(&sk->sk_prot->socks); } static inline void sk_refcnt_debug_dec(struct sock *sk) { atomic_dec(&sk->sk_prot->socks); printk(KERN_DEBUG "%s socket %p released, %d are still alive\n", sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks)); } static inline void sk_refcnt_debug_release(const struct sock *sk) { if (atomic_read(&sk->sk_refcnt) != 1) printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n", sk->sk_prot->name, sk, atomic_read(&sk->sk_refcnt)); } #else /* SOCK_REFCNT_DEBUG */ #define sk_refcnt_debug_inc(sk) do { } while (0) #define sk_refcnt_debug_dec(sk) do { } while (0) #define sk_refcnt_debug_release(sk) do { } while (0) #endif /* SOCK_REFCNT_DEBUG */ #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_NET) extern struct static_key memcg_socket_limit_enabled; #define mem_cgroup_sockets_enabled static_key_false(&memcg_socket_limit_enabled) #else #define mem_cgroup_sockets_enabled 0 #endif static inline bool sk_stream_memory_free(const struct sock *sk) { if (sk->sk_wmem_queued >= sk->sk_sndbuf) return false; return sk->sk_prot->stream_memory_free ? sk->sk_prot->stream_memory_free(sk) : true; } static inline bool sk_stream_is_writeable(const struct sock *sk) { return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) && sk_stream_memory_free(sk); } static inline bool sk_has_memory_pressure(const struct sock *sk) { return sk->sk_prot->memory_pressure != NULL; } static inline bool sk_under_memory_pressure(const struct sock *sk) { if (!sk->sk_prot->memory_pressure) return false; if (mem_cgroup_sockets_enabled && sk->sk_cgrp) return !!*sk->sk_cgrp->memory_pressure; return !!*sk->sk_prot->memory_pressure; } static inline void sk_leave_memory_pressure(struct sock *sk) { int *memory_pressure = sk->sk_prot->memory_pressure; if (!memory_pressure) return; if (*memory_pressure) *memory_pressure = 0; if (mem_cgroup_sockets_enabled && sk->sk_cgrp) if (*sk->sk_cgrp->memory_pressure) *sk->sk_cgrp->memory_pressure = 0; } static inline void sk_enter_memory_pressure(struct sock *sk) { if (!sk->sk_prot->enter_memory_pressure) return; if (mem_cgroup_sockets_enabled && sk->sk_cgrp) sk->sk_cgrp->enter_memory_pressure(sk); sk->sk_prot->enter_memory_pressure(sk); } static inline long sk_prot_mem_limits(const struct sock *sk, int index) { long *prot = sk->sk_prot->sysctl_mem; if (mem_cgroup_sockets_enabled && sk->sk_cgrp) prot = sk->sk_cgrp->sysctl_mem; return prot[index]; } static inline void memcg_memory_allocated_add(struct cg_proto *prot, unsigned long amt, int *parent_status) { struct page_counter *counter; if (page_counter_try_charge(prot->memory_allocated, amt, &counter)) return; page_counter_charge(prot->memory_allocated, amt); *parent_status = OVER_LIMIT; } static inline void memcg_memory_allocated_sub(struct cg_proto *prot, unsigned long amt) { page_counter_uncharge(prot->memory_allocated, amt); } static inline long sk_memory_allocated(const struct sock *sk) { struct proto *prot = sk->sk_prot; if (mem_cgroup_sockets_enabled && sk->sk_cgrp) return page_counter_read(sk->sk_cgrp->memory_allocated); return atomic_long_read(prot->memory_allocated); } static inline long sk_memory_allocated_add(struct sock *sk, int amt, int *parent_status) { struct proto *prot = sk->sk_prot; if (mem_cgroup_sockets_enabled && sk->sk_cgrp) { memcg_memory_allocated_add(sk->sk_cgrp, amt, parent_status); /* update the root cgroup regardless */ atomic_long_add_return(amt, prot->memory_allocated); return page_counter_read(sk->sk_cgrp->memory_allocated); } return atomic_long_add_return(amt, prot->memory_allocated); } static inline void sk_memory_allocated_sub(struct sock *sk, int amt) { struct proto *prot = sk->sk_prot; if (mem_cgroup_sockets_enabled && sk->sk_cgrp) memcg_memory_allocated_sub(sk->sk_cgrp, amt); atomic_long_sub(amt, prot->memory_allocated); } static inline void sk_sockets_allocated_dec(struct sock *sk) { percpu_counter_dec(sk->sk_prot->sockets_allocated); } static inline void sk_sockets_allocated_inc(struct sock *sk) { percpu_counter_inc(sk->sk_prot->sockets_allocated); } static inline int sk_sockets_allocated_read_positive(struct sock *sk) { return percpu_counter_read_positive(sk->sk_prot->sockets_allocated); } static inline int proto_sockets_allocated_sum_positive(struct proto *prot) { return percpu_counter_sum_positive(prot->sockets_allocated); } static inline long proto_memory_allocated(struct proto *prot) { return atomic_long_read(prot->memory_allocated); } static inline bool proto_memory_pressure(struct proto *prot) { if (!prot->memory_pressure) return false; return !!*prot->memory_pressure; } #ifdef CONFIG_PROC_FS /* Called with local bh disabled */ extern void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc); extern int sock_prot_inuse_get(struct net *net, struct proto *proto); #else static inline void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc) { } #endif /* With per-bucket locks this operation is not-atomic, so that * this version is not worse. */ static inline void __sk_prot_rehash(struct sock *sk) { sk->sk_prot->unhash(sk); sk->sk_prot->hash(sk); } void sk_prot_clear_portaddr_nulls(struct sock *sk, int size); /* About 10 seconds */ #define SOCK_DESTROY_TIME (10*HZ) /* Sockets 0-1023 can't be bound to unless you are superuser */ #define PROT_SOCK 1024 #define SHUTDOWN_MASK 3 #define RCV_SHUTDOWN 1 #define SEND_SHUTDOWN 2 #define SOCK_SNDBUF_LOCK 1 #define SOCK_RCVBUF_LOCK 2 #define SOCK_BINDADDR_LOCK 4 #define SOCK_BINDPORT_LOCK 8 /* sock_iocb: used to kick off async processing of socket ios */ struct sock_iocb { struct list_head list; int flags; int size; struct socket *sock; struct sock *sk; struct scm_cookie *scm; struct msghdr *msg, async_msg; struct kiocb *kiocb; }; static inline struct sock_iocb *kiocb_to_siocb(struct kiocb *iocb) { return (struct sock_iocb *)iocb->private; } static inline struct kiocb *siocb_to_kiocb(struct sock_iocb *si) { return si->kiocb; } struct socket_alloc { struct socket socket; struct inode vfs_inode; }; static inline struct socket *SOCKET_I(struct inode *inode) { return &container_of(inode, struct socket_alloc, vfs_inode)->socket; } static inline struct inode *SOCK_INODE(struct socket *socket) { return &container_of(socket, struct socket_alloc, socket)->vfs_inode; } /* * Functions for memory accounting */ int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind); extern int __sk_mem_schedule(struct sock *sk, int size, int kind); void __sk_mem_reduce_allocated(struct sock *sk, int amount); void __sk_mem_reclaim(struct sock *sk, int amount); #define SK_MEM_QUANTUM ((int)PAGE_SIZE) #define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM) #define SK_MEM_SEND 0 #define SK_MEM_RECV 1 static inline int sk_mem_pages(int amt) { return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT; } static inline bool sk_has_account(struct sock *sk) { /* return true if protocol supports memory accounting */ return !!sk->sk_prot->memory_allocated; } static inline bool sk_wmem_schedule(struct sock *sk, int size) { if (!sk_has_account(sk)) return true; return size <= sk->sk_forward_alloc || __sk_mem_schedule(sk, size, SK_MEM_SEND); } static inline bool sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size) { if (!sk_has_account(sk)) return true; return size<= sk->sk_forward_alloc || __sk_mem_schedule(sk, size, SK_MEM_RECV) || skb_pfmemalloc(skb); } static inline void sk_mem_reclaim(struct sock *sk) { if (!sk_has_account(sk)) return; if (sk->sk_forward_alloc >= SK_MEM_QUANTUM) __sk_mem_reclaim(sk, sk->sk_forward_alloc); } static inline void sk_mem_reclaim_partial(struct sock *sk) { if (!sk_has_account(sk)) return; if (sk->sk_forward_alloc > SK_MEM_QUANTUM) __sk_mem_reclaim(sk, sk->sk_forward_alloc - 1); } static inline void sk_mem_charge(struct sock *sk, int size) { if (!sk_has_account(sk)) return; sk->sk_forward_alloc -= size; } static inline void sk_mem_uncharge(struct sock *sk, int size) { if (!sk_has_account(sk)) return; sk->sk_forward_alloc += size; } static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb) { sock_set_flag(sk, SOCK_QUEUE_SHRUNK); sk->sk_wmem_queued -= skb->truesize; sk_mem_uncharge(sk, skb->truesize); __kfree_skb(skb); } /* Used by processes to "lock" a socket state, so that * interrupts and bottom half handlers won't change it * from under us. It essentially blocks any incoming * packets, so that we won't get any new data or any * packets that change the state of the socket. * * While locked, BH processing will add new packets to * the backlog queue. This queue is processed by the * owner of the socket lock right before it is released. * * Since ~2.3.5 it is also exclusive sleep lock serializing * accesses from user process context. */ #define sock_owned_by_user(sk) ((sk)->sk_lock.owned) static inline void sock_release_ownership(struct sock *sk) { if (sk->sk_lock.owned) { sk->sk_lock.owned = 0; /* The sk_lock has mutex_unlock() semantics: */ mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); } } /* * Macro so as to not evaluate some arguments when * lockdep is not enabled. * * Mark both the sk_lock and the sk_lock.slock as a * per-address-family lock class. */ #define sock_lock_init_class_and_name(sk, sname, skey, name, key) \ do { \ sk->sk_lock.owned = 0; \ init_waitqueue_head(&sk->sk_lock.wq); \ spin_lock_init(&(sk)->sk_lock.slock); \ debug_check_no_locks_freed((void *)&(sk)->sk_lock, \ sizeof((sk)->sk_lock)); \ lockdep_set_class_and_name(&(sk)->sk_lock.slock, \ (skey), (sname)); \ lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \ } while (0) #ifdef CONFIG_LOCKDEP static inline bool lockdep_sock_is_held(const struct sock *csk) { struct sock *sk = (struct sock *)csk; return lockdep_is_held(&sk->sk_lock) || lockdep_is_held(&sk->sk_lock.slock); } #endif extern void lock_sock_nested(struct sock *sk, int subclass); static inline void lock_sock(struct sock *sk) { lock_sock_nested(sk, 0); } extern void release_sock(struct sock *sk); /* BH context may only use the following locking interface. */ #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock)) #define bh_lock_sock_nested(__sk) \ spin_lock_nested(&((__sk)->sk_lock.slock), \ SINGLE_DEPTH_NESTING) #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock)) extern bool lock_sock_fast(struct sock *sk); /** * unlock_sock_fast - complement of lock_sock_fast * @sk: socket * @slow: slow mode * * fast unlock socket for user context. * If slow mode is on, we call regular release_sock() */ static inline void unlock_sock_fast(struct sock *sk, bool slow) { if (slow) release_sock(sk); else spin_unlock_bh(&sk->sk_lock.slock); } extern struct sock *sk_alloc(struct net *net, int family, gfp_t priority, struct proto *prot); extern void sk_free(struct sock *sk); extern void sk_release_kernel(struct sock *sk); extern struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority); extern struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, gfp_t priority); extern struct sk_buff *sock_rmalloc(struct sock *sk, unsigned long size, int force, gfp_t priority); void __sock_wfree(struct sk_buff *skb); extern void sock_wfree(struct sk_buff *skb); extern void skb_orphan_partial(struct sk_buff *skb); extern void sock_rfree(struct sk_buff *skb); extern void sock_efree(struct sk_buff *skb); #ifdef CONFIG_INET void sock_edemux(struct sk_buff *skb); #else #define sock_edemux sock_efree #endif extern int sock_setsockopt(struct socket *sock, int level, int op, char __user *optval, unsigned int optlen); extern int sock_getsockopt(struct socket *sock, int level, int op, char __user *optval, int __user *optlen); extern struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, int noblock, int *errcode); extern struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, unsigned long data_len, int noblock, int *errcode, int max_page_order); extern void *sock_kmalloc(struct sock *sk, int size, gfp_t priority); extern void sock_kfree_s(struct sock *sk, void *mem, int size); extern void sock_kzfree_s(struct sock *sk, void *mem, int size); extern void sk_send_sigurg(struct sock *sk); /* * Functions to fill in entries in struct proto_ops when a protocol * does not implement a particular function. */ extern int sock_no_bind(struct socket *, struct sockaddr *, int); extern int sock_no_connect(struct socket *, struct sockaddr *, int, int); extern int sock_no_socketpair(struct socket *, struct socket *); extern int sock_no_accept(struct socket *, struct socket *, int); extern int sock_no_getname(struct socket *, struct sockaddr *, int *, int); extern unsigned int sock_no_poll(struct file *, struct socket *, struct poll_table_struct *); extern int sock_no_ioctl(struct socket *, unsigned int, unsigned long); extern int sock_no_listen(struct socket *, int); extern int sock_no_shutdown(struct socket *, int); extern int sock_no_getsockopt(struct socket *, int , int, char __user *, int __user *); extern int sock_no_setsockopt(struct socket *, int, int, char __user *, unsigned int); extern int sock_no_sendmsg(struct kiocb *, struct socket *, struct msghdr *, size_t); extern int sock_no_recvmsg(struct kiocb *, struct socket *, struct msghdr *, size_t, int); extern int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma); extern ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags); /* * Functions to fill in entries in struct proto_ops when a protocol * uses the inet style. */ extern int sock_common_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen); extern int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg, size_t size, int flags); extern int sock_common_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen); extern int compat_sock_common_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen); extern int compat_sock_common_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen); extern void sk_common_release(struct sock *sk); /* * Default socket callbacks and setup code */ /* Initialise core socket variables */ extern void sock_init_data(struct socket *sock, struct sock *sk); extern void sk_filter_release_rcu(struct rcu_head *rcu); /** * sk_filter_release - release a socket filter * @fp: filter to remove * * Remove a filter from a socket and release its resources. */ static inline void sk_filter_release(struct sk_filter *fp) { if (atomic_dec_and_test(&fp->refcnt)) call_rcu(&fp->rcu, sk_filter_release_rcu); } static inline void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp) { unsigned int size = sk_filter_len(fp); atomic_sub(size, &sk->sk_omem_alloc); sk_filter_release(fp); } static inline void sk_filter_charge(struct sock *sk, struct sk_filter *fp) { atomic_inc(&fp->refcnt); atomic_add(sk_filter_len(fp), &sk->sk_omem_alloc); } /* * Socket reference counting postulates. * * * Each user of socket SHOULD hold a reference count. * * Each access point to socket (an hash table bucket, reference from a list, * running timer, skb in flight MUST hold a reference count. * * When reference count hits 0, it means it will never increase back. * * When reference count hits 0, it means that no references from * outside exist to this socket and current process on current CPU * is last user and may/should destroy this socket. * * sk_free is called from any context: process, BH, IRQ. When * it is called, socket has no references from outside -> sk_free * may release descendant resources allocated by the socket, but * to the time when it is called, socket is NOT referenced by any * hash tables, lists etc. * * Packets, delivered from outside (from network or from another process) * and enqueued on receive/error queues SHOULD NOT grab reference count, * when they sit in queue. Otherwise, packets will leak to hole, when * socket is looked up by one cpu and unhasing is made by another CPU. * It is true for udp/raw, netlink (leak to receive and error queues), tcp * (leak to backlog). Packet socket does all the processing inside * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets * use separate SMP lock, so that they are prone too. */ /* Ungrab socket and destroy it, if it was the last reference. */ static inline void sock_put(struct sock *sk) { if (atomic_dec_and_test(&sk->sk_refcnt)) sk_free(sk); } /* Generic version of sock_put(), dealing with all sockets * (TCP_TIMEWAIT, ESTABLISHED...) */ void sock_gen_put(struct sock *sk); extern int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested); static inline void sk_tx_queue_set(struct sock *sk, int tx_queue) { sk->sk_tx_queue_mapping = tx_queue; } static inline void sk_tx_queue_clear(struct sock *sk) { sk->sk_tx_queue_mapping = -1; } static inline int sk_tx_queue_get(const struct sock *sk) { return sk ? sk->sk_tx_queue_mapping : -1; } static inline void sk_set_socket(struct sock *sk, struct socket *sock) { sk_tx_queue_clear(sk); sk->sk_socket = sock; } static inline wait_queue_head_t *sk_sleep(struct sock *sk) { BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0); return &rcu_dereference_raw(sk->sk_wq)->wait; } /* Detach socket from process context. * Announce socket dead, detach it from wait queue and inode. * Note that parent inode held reference count on this struct sock, * we do not release it in this function, because protocol * probably wants some additional cleanups or even continuing * to work with this socket (TCP). */ static inline void sock_orphan(struct sock *sk) { write_lock_bh(&sk->sk_callback_lock); sock_set_flag(sk, SOCK_DEAD); sk_set_socket(sk, NULL); sk->sk_wq = NULL; write_unlock_bh(&sk->sk_callback_lock); } static inline void sock_graft(struct sock *sk, struct socket *parent) { write_lock_bh(&sk->sk_callback_lock); sk->sk_wq = parent->wq; parent->sk = sk; sk_set_socket(sk, parent); security_sock_graft(sk, parent); write_unlock_bh(&sk->sk_callback_lock); } extern kuid_t sock_i_uid(struct sock *sk); extern unsigned long sock_i_ino(struct sock *sk); static inline void sk_set_txhash(struct sock *sk) { sk->sk_txhash = prandom_u32(); if (unlikely(!sk->sk_txhash)) sk->sk_txhash = 1; } static inline struct dst_entry * __sk_dst_get(struct sock *sk) { return rcu_dereference_check(sk->sk_dst_cache, lockdep_sock_is_held(sk)); } static inline struct dst_entry * sk_dst_get(struct sock *sk) { struct dst_entry *dst; rcu_read_lock(); dst = rcu_dereference(sk->sk_dst_cache); if (dst && !atomic_inc_not_zero(&dst->__refcnt)) dst = NULL; rcu_read_unlock(); return dst; } extern void sk_reset_txq(struct sock *sk); static inline void dst_negative_advice(struct sock *sk) { struct dst_entry *ndst, *dst = __sk_dst_get(sk); if (dst && dst->ops->negative_advice) { ndst = dst->ops->negative_advice(dst); if (ndst != dst) { rcu_assign_pointer(sk->sk_dst_cache, ndst); sk_reset_txq(sk); sk->sk_dst_pending_confirm = 0; } } } static inline void __sk_dst_set(struct sock *sk, struct dst_entry *dst) { struct dst_entry *old_dst; sk_tx_queue_clear(sk); sk->sk_dst_pending_confirm = 0; /* * This can be called while sk is owned by the caller only, * with no state that can be checked in a rcu_dereference_check() cond */ old_dst = rcu_dereference_raw(sk->sk_dst_cache); rcu_assign_pointer(sk->sk_dst_cache, dst); dst_release(old_dst); } static inline void sk_dst_set(struct sock *sk, struct dst_entry *dst) { struct dst_entry *old_dst; sk_tx_queue_clear(sk); sk->sk_dst_pending_confirm = 0; old_dst = xchg(&sk->sk_dst_cache, dst); dst_release(old_dst); } static inline void __sk_dst_reset(struct sock *sk) { __sk_dst_set(sk, NULL); } static inline void sk_dst_reset(struct sock *sk) { sk_dst_set(sk, NULL); } extern struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie); extern struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie); static inline void sk_dst_confirm(struct sock *sk) { if (!sk->sk_dst_pending_confirm) sk->sk_dst_pending_confirm = 1; } static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n) { if (skb_get_dst_pending_confirm(skb)) { struct sock *sk = skb->sk; unsigned long now = jiffies; /* avoid dirtying neighbour */ if (n->confirmed != now) n->confirmed = now; if (sk && sk->sk_dst_pending_confirm) sk->sk_dst_pending_confirm = 0; } } bool sk_mc_loop(struct sock *sk); static inline bool sk_can_gso(const struct sock *sk) { return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type); } extern void sk_setup_caps(struct sock *sk, struct dst_entry *dst); static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags) { sk->sk_route_nocaps |= flags; sk->sk_route_caps &= ~flags; } static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb, char __user *from, char *to, int copy, int offset) { if (skb->ip_summed == CHECKSUM_NONE) { int err = 0; __wsum csum = csum_and_copy_from_user(from, to, copy, 0, &err); if (err) return err; skb->csum = csum_block_add(skb->csum, csum, offset); } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) { if (!access_ok(VERIFY_READ, from, copy) || __copy_from_user_nocache(to, from, copy)) return -EFAULT; } else if (copy_from_user(to, from, copy)) return -EFAULT; return 0; } static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb, char __user *from, int copy) { int err, offset = skb->len; err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy), copy, offset); if (err) __skb_trim(skb, offset); return err; } static inline int skb_copy_to_page_nocache(struct sock *sk, char __user *from, struct sk_buff *skb, struct page *page, int off, int copy) { int err; err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off, copy, skb->len); if (err) return err; skb->len += copy; skb->data_len += copy; skb->truesize += copy; sk->sk_wmem_queued += copy; sk_mem_charge(sk, copy); return 0; } static inline int skb_copy_to_page(struct sock *sk, char __user *from, struct sk_buff *skb, struct page *page, int off, int copy) { if (skb->ip_summed == CHECKSUM_NONE) { int err = 0; __wsum csum = csum_and_copy_from_user(from, page_address(page) + off, copy, 0, &err); if (err) return err; skb->csum = csum_block_add(skb->csum, csum, skb->len); } else if (copy_from_user(page_address(page) + off, from, copy)) return -EFAULT; skb->len += copy; skb->data_len += copy; skb->truesize += copy; sk->sk_wmem_queued += copy; sk_mem_charge(sk, copy); return 0; } /** * sk_wmem_alloc_get - returns write allocations * @sk: socket * * Returns sk_wmem_alloc minus initial offset of one */ static inline int sk_wmem_alloc_get(const struct sock *sk) { return atomic_read(&sk->sk_wmem_alloc) - 1; } /** * sk_rmem_alloc_get - returns read allocations * @sk: socket * * Returns sk_rmem_alloc */ static inline int sk_rmem_alloc_get(const struct sock *sk) { return atomic_read(&sk->sk_rmem_alloc); } /** * sk_has_allocations - check if allocations are outstanding * @sk: socket * * Returns true if socket has write or read allocations */ static inline bool sk_has_allocations(const struct sock *sk) { return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk); } /** * wq_has_sleeper - check if there are any waiting processes * @wq: struct socket_wq * * Returns true if socket_wq has waiting processes * * The purpose of the wq_has_sleeper and sock_poll_wait is to wrap the memory * barrier call. They were added due to the race found within the tcp code. * * Consider following tcp code paths: * * CPU1 CPU2 * * sys_select receive packet * ... ... * __add_wait_queue update tp->rcv_nxt * ... ... * tp->rcv_nxt check sock_def_readable * ... { * schedule rcu_read_lock(); * wq = rcu_dereference(sk->sk_wq); * if (wq && waitqueue_active(&wq->wait)) * wake_up_interruptible(&wq->wait) * ... * } * * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1 * could then endup calling schedule and sleep forever if there are no more * data on the socket. * */ static inline bool wq_has_sleeper(struct socket_wq *wq) { /* We need to be sure we are in sync with the * add_wait_queue modifications to the wait queue. * * This memory barrier is paired in the sock_poll_wait. */ smp_mb(); return wq && waitqueue_active(&wq->wait); } /** * sock_poll_wait - place memory barrier behind the poll_wait call. * @filp: file * @wait_address: socket wait queue * @p: poll_table * * See the comments in the wq_has_sleeper function. */ static inline void sock_poll_wait(struct file *filp, wait_queue_head_t *wait_address, poll_table *p) { if (!poll_does_not_wait(p) && wait_address) { poll_wait(filp, wait_address, p); /* We need to be sure we are in sync with the * socket flags modification. * * This memory barrier is paired in the wq_has_sleeper. */ smp_mb(); } } static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk) { if (sk->sk_txhash) { skb->l4_hash = 1; skb->hash = sk->sk_txhash; } } /* * Queue a received datagram if it will fit. Stream and sequenced * protocols can't normally use this as they need to fit buffers in * and play with them. * * Inlined as it's very short and called for pretty much every * packet ever received. */ static inline void skb_set_owner_w(struct sk_buff *skb, struct sock *sk) { skb_orphan(skb); skb->sk = sk; skb->destructor = sock_wfree; skb_set_hash_from_sk(skb, sk); /* * We used to take a refcount on sk, but following operation * is enough to guarantee sk_free() wont free this sock until * all in-flight packets are completed */ atomic_add(skb->truesize, &sk->sk_wmem_alloc); } static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk) { skb_orphan(skb); skb->sk = sk; skb->destructor = sock_rfree; atomic_add(skb->truesize, &sk->sk_rmem_alloc); sk_mem_charge(sk, skb->truesize); } extern void sk_reset_timer(struct sock *sk, struct timer_list *timer, unsigned long expires); extern void sk_stop_timer(struct sock *sk, struct timer_list *timer); int __sk_queue_drop_skb(struct sock *sk, struct sk_buff *skb, unsigned int flags, void (*destructor)(struct sock *sk, struct sk_buff *skb)); int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); extern int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); extern int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb); /* * Recover an error report and clear atomically */ static inline int sock_error(struct sock *sk) { int err; if (likely(!sk->sk_err)) return 0; err = xchg(&sk->sk_err, 0); return -err; } static inline unsigned long sock_wspace(struct sock *sk) { int amt = 0; if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { amt = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc); if (amt < 0) amt = 0; } return amt; } static inline void sk_wake_async(struct sock *sk, int how, int band) { if (sock_flag(sk, SOCK_FASYNC)) sock_wake_async(sk->sk_socket, how, band); } /* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak. * Note: for send buffers, TCP works better if we can build two skbs at * minimum. */ #define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff))) #define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2) #define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE static inline void sk_stream_moderate_sndbuf(struct sock *sk) { if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) { sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1); sk->sk_sndbuf = max_t(u32, sk->sk_sndbuf, SOCK_MIN_SNDBUF); } } struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp); /** * sk_page_frag - return an appropriate page_frag * @sk: socket * * If socket allocation mode allows current thread to sleep, it means its * safe to use the per task page_frag instead of the per socket one. */ static inline struct page_frag *sk_page_frag(struct sock *sk) { if (sk->sk_allocation & __GFP_WAIT) return ¤t->task_frag; return &sk->sk_frag; } extern bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag); /* * Default write policy as shown to user space via poll/select/SIGIO */ static inline bool sock_writeable(const struct sock *sk) { return atomic_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf >> 1); } static inline gfp_t gfp_any(void) { return in_softirq() ? GFP_ATOMIC : GFP_KERNEL; } static inline long sock_rcvtimeo(const struct sock *sk, bool noblock) { return noblock ? 0 : sk->sk_rcvtimeo; } static inline long sock_sndtimeo(const struct sock *sk, bool noblock) { return noblock ? 0 : sk->sk_sndtimeo; } static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len) { return (waitall ? len : min_t(int, sk->sk_rcvlowat, len)) ? : 1; } /* Alas, with timeout socket operations are not restartable. * Compare this to poll(). */ static inline int sock_intr_errno(long timeo) { return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR; } static inline void sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb) { skb->dropcount = atomic_read(&sk->sk_drops); } static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb) { int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs); atomic_add(segs, &sk->sk_drops); } extern void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb); extern void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk, struct sk_buff *skb); static inline void sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb) { ktime_t kt = skb->tstamp; struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb); /* * generate control messages if * - receive time stamping in software requested * - software time stamp available and wanted * - hardware time stamps available and wanted */ if (sock_flag(sk, SOCK_RCVTSTAMP) || (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) || (kt.tv64 && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) || (hwtstamps->hwtstamp.tv64 && (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)) || (hwtstamps->syststamp.tv64 && (sk->sk_tsflags & SOF_TIMESTAMPING_SYS_HARDWARE))) __sock_recv_timestamp(msg, sk, skb); else sk->sk_stamp = kt; if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid) __sock_recv_wifi_status(msg, sk, skb); } extern void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk, struct sk_buff *skb); static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk, struct sk_buff *skb) { #define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \ (1UL << SOCK_RCVTSTAMP)) #define TSFLAGS_ANY (SOF_TIMESTAMPING_SOFTWARE | \ SOF_TIMESTAMPING_RAW_HARDWARE | \ SOF_TIMESTAMPING_SYS_HARDWARE) if (sk->sk_flags & FLAGS_TS_OR_DROPS || sk->sk_tsflags & TSFLAGS_ANY) __sock_recv_ts_and_drops(msg, sk, skb); else sk->sk_stamp = skb->tstamp; } /** * sock_tx_timestamp - checks whether the outgoing packet is to be time stamped * @sk: socket sending this packet * @tx_flags: filled with instructions for time stamping */ extern void sock_tx_timestamp(struct sock *sk, __u8 *tx_flags); /** * sk_eat_skb - Release a skb if it is no longer needed * @sk: socket to eat this skb from * @skb: socket buffer to eat * * This routine must be called with interrupts disabled or with the socket * locked so that the sk_buff queue operation is ok. */ static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb) { __skb_unlink(skb, &sk->sk_receive_queue); __kfree_skb(skb); } static inline struct net *sock_net(const struct sock *sk) { return read_pnet(&sk->sk_net); } static inline void sock_net_set(struct sock *sk, struct net *net) { write_pnet(&sk->sk_net, net); } /* * Kernel sockets, f.e. rtnl or icmp_socket, are a part of a namespace. * They should not hold a reference to a namespace in order to allow * to stop it. * Sockets after sk_change_net should be released using sk_release_kernel */ static inline void sk_change_net(struct sock *sk, struct net *net) { struct net *current_net = sock_net(sk); if (!net_eq(current_net, net)) { put_net(current_net); sock_net_set(sk, net); } } static inline struct sock *skb_steal_sock(struct sk_buff *skb) { if (skb->sk) { struct sock *sk = skb->sk; skb->destructor = NULL; skb->sk = NULL; return sk; } return NULL; } extern void sock_enable_timestamp(struct sock *sk, int flag); extern int sock_get_timestamp(struct sock *, struct timeval __user *); extern int sock_get_timestampns(struct sock *, struct timespec __user *); /* * Enable debug/info messages */ extern int net_msg_warn; #define NETDEBUG(fmt, args...) \ do { if (net_msg_warn) printk(fmt,##args); } while (0) #define LIMIT_NETDEBUG(fmt, args...) \ do { if (net_msg_warn && net_ratelimit()) printk(fmt,##args); } while(0) /* This helper checks if a socket is a full socket, * ie _not_ a timewait socket. */ static inline bool sk_fullsock(const struct sock *sk) { return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT); } bool sk_ns_capable(const struct sock *sk, struct user_namespace *user_ns, int cap); bool sk_capable(const struct sock *sk, int cap); bool sk_net_capable(const struct sock *sk, int cap); extern __u32 sysctl_wmem_max; extern __u32 sysctl_rmem_max; extern int sysctl_optmem_max; extern __u32 sysctl_wmem_default; extern __u32 sysctl_rmem_default; #endif /* _SOCK_H */