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Diffstat (limited to 'include/net/sock.h')
| -rw-r--r-- | include/net/sock.h | 2820 |
1 files changed, 2820 insertions, 0 deletions
diff --git a/include/net/sock.h b/include/net/sock.h new file mode 100644 index 000000000..87ee284ea --- /dev/null +++ b/include/net/sock.h @@ -0,0 +1,2820 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * 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 + */ +#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> +#include <linux/page_counter.h> +#include <linux/memcontrol.h> +#include <linux/static_key.h> +#include <linux/sched.h> +#include <linux/wait.h> +#include <linux/cgroup-defs.h> +#include <linux/rbtree.h> +#include <linux/filter.h> +#include <linux/rculist_nulls.h> +#include <linux/poll.h> +#include <linux/sockptr.h> + +#include <linux/atomic.h> +#include <linux/refcount.h> +#include <net/dst.h> +#include <net/checksum.h> +#include <net/tcp_states.h> +#include <linux/net_tstamp.h> +#include <net/l3mdev.h> + +/* + * 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_addrpair: 8-byte-aligned __u64 union of @skc_daddr & @skc_rcv_saddr + * @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_portpair: __u32 union of @skc_dport & @skc_num + * @skc_family: network address family + * @skc_state: Connection state + * @skc_reuse: %SO_REUSEADDR setting + * @skc_reuseport: %SO_REUSEPORT setting + * @skc_ipv6only: socket is IPV6 only + * @skc_net_refcnt: socket is using net ref counting + * @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_v6_daddr: IPV6 destination address + * @skc_v6_rcv_saddr: IPV6 source address + * @skc_cookie: socket's cookie value + * @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_rx_queue_mapping: rx queue number for this connection + * @skc_flags: place holder for sk_flags + * %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE, + * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings + * @skc_listener: connection request listener socket (aka rsk_listener) + * [union with @skc_flags] + * @skc_tw_dr: (aka tw_dr) ptr to &struct inet_timewait_death_row + * [union with @skc_flags] + * @skc_incoming_cpu: record/match cpu processing incoming packets + * @skc_rcv_wnd: (aka rsk_rcv_wnd) TCP receive window size (possibly scaled) + * [union with @skc_incoming_cpu] + * @skc_tw_rcv_nxt: (aka tw_rcv_nxt) TCP window next expected seq number + * [union with @skc_incoming_cpu] + * @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 { + 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:1; + unsigned char skc_ipv6only:1; + unsigned char skc_net_refcnt:1; + int skc_bound_dev_if; + union { + struct hlist_node skc_bind_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 + + atomic64_t skc_cookie; + + /* following fields are padding to force + * offset(struct sock, sk_refcnt) == 128 on 64bit arches + * assuming IPV6 is enabled. We use this padding differently + * for different kind of 'sockets' + */ + union { + unsigned long skc_flags; + struct sock *skc_listener; /* request_sock */ + struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */ + }; + /* + * 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; + }; + unsigned short skc_tx_queue_mapping; +#ifdef CONFIG_XPS + unsigned short skc_rx_queue_mapping; +#endif + union { + int skc_incoming_cpu; + u32 skc_rcv_wnd; + u32 skc_tw_rcv_nxt; /* struct tcp_timewait_sock */ + }; + + refcount_t skc_refcnt; + /* private: */ + int skc_dontcopy_end[0]; + union { + u32 skc_rxhash; + u32 skc_window_clamp; + u32 skc_tw_snd_nxt; /* struct tcp_timewait_sock */ + }; + /* public: */ +}; + +struct bpf_local_storage; + +/** + * 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_kern_sock: True if sock is using kernel lock classes + * @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_rx_skb_cache: cache copy of recently accessed RX skb + * @sk_receive_queue: incoming packets + * @sk_wmem_alloc: transmit queue bytes committed + * @sk_tsq_flags: TCP Small Queues flags + * @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_pacing_status: Pacing status (requested, handled by sch_fq) + * @sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE) + * @sk_sndbuf: size of send buffer in bytes + * @__sk_flags_offset: empty field used to determine location of bitfield + * @sk_padding: unused element for alignment + * @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_route_forced_caps: static, forced route capabilities + * (set in tcp_init_sock()) + * @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_pacing_shift: scaling factor for TCP Small Queues + * @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_uid: user id of owner + * @sk_priority: %SO_PRIORITY setting + * @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_txhash: computed flow hash for use on transmit + * @sk_filter: socket filtering instructions + * @sk_timer: sock cleanup timer + * @sk_stamp: time stamp of last packet received + * @sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only + * @sk_tsflags: SO_TIMESTAMPING socket options + * @sk_tskey: counter to disambiguate concurrent tstamp requests + * @sk_zckey: counter to order MSG_ZEROCOPY notifications + * @sk_socket: Identd and reporting IO signals + * @sk_user_data: RPC layer private data. Write-protected by @sk_callback_lock. + * @sk_frag: cached page frag + * @sk_peek_off: current peek_offset value + * @sk_send_head: front of stuff to transmit + * @tcp_rtx_queue: TCP re-transmit queue [union with @sk_send_head] + * @sk_tx_skb_cache: cache copy of recently accessed TX skb + * @sk_security: used by security modules + * @sk_mark: generic packet mark + * @sk_cgrp_data: cgroup data for this cgroup + * @sk_memcg: this socket's memory cgroup association + * @sk_write_pending: a write to stream socket waits to start + * @sk_wait_pending: number of threads blocked on this socket + * @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_validate_xmit_skb: ptr to an optional validate function + * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0 + * @sk_reuseport_cb: reuseport group container + * @sk_bpf_storage: ptr to cache and control for bpf_sk_storage + * @sk_rcu: used during RCU grace period + * @sk_clockid: clockid used by time-based scheduling (SO_TXTIME) + * @sk_txtime_deadline_mode: set deadline mode for SO_TXTIME + * @sk_txtime_report_errors: set report errors mode for SO_TXTIME + * @sk_txtime_unused: unused txtime flags + */ +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 +#ifdef CONFIG_XPS +#define sk_rx_queue_mapping __sk_common.skc_rx_queue_mapping +#endif + +#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_ipv6only __sk_common.skc_ipv6only +#define sk_net_refcnt __sk_common.skc_net_refcnt +#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 +#define sk_cookie __sk_common.skc_cookie +#define sk_incoming_cpu __sk_common.skc_incoming_cpu +#define sk_flags __sk_common.skc_flags +#define sk_rxhash __sk_common.skc_rxhash + + socket_lock_t sk_lock; + atomic_t sk_drops; + int sk_rcvlowat; + struct sk_buff_head sk_error_queue; + struct sk_buff *sk_rx_skb_cache; + 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_NET_RX_BUSY_POLL + unsigned int sk_ll_usec; + /* ===== mostly read cache line ===== */ + unsigned int sk_napi_id; +#endif + int sk_rcvbuf; + int sk_wait_pending; + + struct sk_filter __rcu *sk_filter; + union { + struct socket_wq __rcu *sk_wq; + /* private: */ + struct socket_wq *sk_wq_raw; + /* public: */ + }; +#ifdef CONFIG_XFRM + struct xfrm_policy __rcu *sk_policy[2]; +#endif + struct dst_entry __rcu *sk_rx_dst; + struct dst_entry __rcu *sk_dst_cache; + atomic_t sk_omem_alloc; + int sk_sndbuf; + + /* ===== cache line for TX ===== */ + int sk_wmem_queued; + refcount_t sk_wmem_alloc; + unsigned long sk_tsq_flags; + union { + struct sk_buff *sk_send_head; + struct rb_root tcp_rtx_queue; + }; + struct sk_buff *sk_tx_skb_cache; + struct sk_buff_head sk_write_queue; + __s32 sk_peek_off; + int sk_write_pending; + __u32 sk_dst_pending_confirm; + u32 sk_pacing_status; /* see enum sk_pacing */ + long sk_sndtimeo; + struct timer_list sk_timer; + __u32 sk_priority; + __u32 sk_mark; + unsigned long sk_pacing_rate; /* bytes per second */ + unsigned long sk_max_pacing_rate; + struct page_frag sk_frag; + netdev_features_t sk_route_caps; + netdev_features_t sk_route_nocaps; + netdev_features_t sk_route_forced_caps; + int sk_gso_type; + unsigned int sk_gso_max_size; + gfp_t sk_allocation; + __u32 sk_txhash; + + /* + * Because of non atomicity rules, all + * changes are protected by socket lock. + */ + u8 sk_padding : 1, + sk_kern_sock : 1, + sk_no_check_tx : 1, + sk_no_check_rx : 1, + sk_userlocks : 4; + u8 sk_pacing_shift; + u16 sk_type; + u16 sk_protocol; + u16 sk_gso_max_segs; + unsigned long sk_lingertime; + struct proto *sk_prot_creator; + rwlock_t sk_callback_lock; + int sk_err, + sk_err_soft; + u32 sk_ack_backlog; + u32 sk_max_ack_backlog; + kuid_t sk_uid; + spinlock_t sk_peer_lock; + struct pid *sk_peer_pid; + const struct cred *sk_peer_cred; + + long sk_rcvtimeo; + ktime_t sk_stamp; +#if BITS_PER_LONG==32 + seqlock_t sk_stamp_seq; +#endif + u16 sk_tsflags; + u8 sk_shutdown; + u32 sk_tskey; + atomic_t sk_zckey; + + u8 sk_clockid; + u8 sk_txtime_deadline_mode : 1, + sk_txtime_report_errors : 1, + sk_txtime_unused : 6; + + struct socket *sk_socket; + void *sk_user_data; +#ifdef CONFIG_SECURITY + void *sk_security; +#endif + struct sock_cgroup_data sk_cgrp_data; + struct mem_cgroup *sk_memcg; + void (*sk_state_change)(struct sock *sk); + void (*sk_data_ready)(struct sock *sk); + 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); +#ifdef CONFIG_SOCK_VALIDATE_XMIT + struct sk_buff* (*sk_validate_xmit_skb)(struct sock *sk, + struct net_device *dev, + struct sk_buff *skb); +#endif + void (*sk_destruct)(struct sock *sk); + struct sock_reuseport __rcu *sk_reuseport_cb; +#ifdef CONFIG_BPF_SYSCALL + struct bpf_local_storage __rcu *sk_bpf_storage; +#endif + struct rcu_head sk_rcu; +}; + +enum sk_pacing { + SK_PACING_NONE = 0, + SK_PACING_NEEDED = 1, + SK_PACING_FQ = 2, +}; + +/* flag bits in sk_user_data + * + * - SK_USER_DATA_NOCOPY: Pointer stored in sk_user_data might + * not be suitable for copying when cloning the socket. For instance, + * it can point to a reference counted object. sk_user_data bottom + * bit is set if pointer must not be copied. + * + * - SK_USER_DATA_BPF: Mark whether sk_user_data field is + * managed/owned by a BPF reuseport array. This bit should be set + * when sk_user_data's sk is added to the bpf's reuseport_array. + * + * - SK_USER_DATA_PSOCK: Mark whether pointer stored in + * sk_user_data points to psock type. This bit should be set + * when sk_user_data is assigned to a psock object. + */ +#define SK_USER_DATA_NOCOPY 1UL +#define SK_USER_DATA_BPF 2UL +#define SK_USER_DATA_PSOCK 4UL +#define SK_USER_DATA_PTRMASK ~(SK_USER_DATA_NOCOPY | SK_USER_DATA_BPF |\ + SK_USER_DATA_PSOCK) + +/** + * sk_user_data_is_nocopy - Test if sk_user_data pointer must not be copied + * @sk: socket + */ +static inline bool sk_user_data_is_nocopy(const struct sock *sk) +{ + return ((uintptr_t)sk->sk_user_data & SK_USER_DATA_NOCOPY); +} + +#define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data))) + +/** + * __rcu_dereference_sk_user_data_with_flags - return the pointer + * only if argument flags all has been set in sk_user_data. Otherwise + * return NULL + * + * @sk: socket + * @flags: flag bits + */ +static inline void * +__rcu_dereference_sk_user_data_with_flags(const struct sock *sk, + uintptr_t flags) +{ + uintptr_t sk_user_data = (uintptr_t)rcu_dereference(__sk_user_data(sk)); + + WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK); + + if ((sk_user_data & flags) == flags) + return (void *)(sk_user_data & SK_USER_DATA_PTRMASK); + return NULL; +} + +#define rcu_dereference_sk_user_data(sk) \ + __rcu_dereference_sk_user_data_with_flags(sk, 0) +#define __rcu_assign_sk_user_data_with_flags(sk, ptr, flags) \ +({ \ + uintptr_t __tmp1 = (uintptr_t)(ptr), \ + __tmp2 = (uintptr_t)(flags); \ + WARN_ON_ONCE(__tmp1 & ~SK_USER_DATA_PTRMASK); \ + WARN_ON_ONCE(__tmp2 & SK_USER_DATA_PTRMASK); \ + rcu_assign_pointer(__sk_user_data((sk)), \ + __tmp1 | __tmp2); \ +}) +#define rcu_assign_sk_user_data(sk, ptr) \ + __rcu_assign_sk_user_data_with_flags(sk, ptr, 0) + +/* + * 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 + +int sk_set_peek_off(struct sock *sk, int val); + +static inline int sk_peek_offset(struct sock *sk, int flags) +{ + if (unlikely(flags & MSG_PEEK)) { + return READ_ONCE(sk->sk_peek_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 hlist_entry_safe(sk->sk_node.next, struct sock, sk_node); +} + +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 __always_inline void sock_hold(struct sock *sk) +{ + refcount_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 __always_inline void __sock_put(struct sock *sk) +{ + refcount_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(refcount_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(refcount_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_add_node_tail_rcu(struct sock *sk, struct hlist_head *list) +{ + sock_hold(sk); + hlist_add_tail_rcu(&sk->sk_node, list); +} + +static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list) +{ + hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list); +} + +static inline void __sk_nulls_add_node_tail_rcu(struct sock *sk, struct hlist_nulls_head *list) +{ + hlist_nulls_add_tail_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(hlist_first_rcu(head)); \ + pos != NULL && \ + ({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \ + pos = rcu_dereference(hlist_next_rcu(pos))) + +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_MEMALLOC, /* VM depends on this socket for swapping */ + SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */ + 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() */ + SOCK_TXTIME, + SOCK_XDP, /* XDP is attached */ + SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */ +}; + +#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 void sock_valbool_flag(struct sock *sk, enum sock_flags bit, + int valbool) +{ + if (valbool) + sock_set_flag(sk, bit); + else + sock_reset_flag(sk, bit); +} + +static inline bool sock_flag(const struct sock *sk, enum sock_flags flag) +{ + return test_bit(flag, &sk->sk_flags); +} + +#ifdef CONFIG_NET +DECLARE_STATIC_KEY_FALSE(memalloc_socks_key); +static inline int sk_memalloc_socks(void) +{ + return static_branch_unlikely(&memalloc_socks_key); +} + +void __receive_sock(struct file *file); +#else + +static inline int sk_memalloc_socks(void) +{ + return 0; +} + +static inline void __receive_sock(struct file *file) +{ } +#endif + +static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask) +{ + return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC); +} + +static inline void sk_acceptq_removed(struct sock *sk) +{ + WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1); +} + +static inline void sk_acceptq_added(struct sock *sk) +{ + WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1); +} + +static inline bool sk_acceptq_is_full(const struct sock *sk) +{ + return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(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 READ_ONCE(sk->sk_wmem_queued) >> 1; +} + +static inline int sk_stream_wspace(const struct sock *sk) +{ + return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued); +} + +static inline void sk_wmem_queued_add(struct sock *sk, int val) +{ + WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val); +} + +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(skb); + + if (!sk->sk_backlog.tail) + WRITE_ONCE(sk->sk_backlog.head, skb); + else + sk->sk_backlog.tail->next = skb; + + WRITE_ONCE(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, 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, 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; +} + +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 sk_incoming_cpu_update(struct sock *sk) +{ + int cpu = raw_smp_processor_id(); + + if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu)) + WRITE_ONCE(sk->sk_incoming_cpu, cpu); +} + +static inline void sock_rps_record_flow_hash(__u32 hash) +{ +#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, hash); + rcu_read_unlock(); +#endif +} + +static inline void sock_rps_record_flow(const struct sock *sk) +{ +#ifdef CONFIG_RPS + if (static_branch_unlikely(&rfs_needed)) { + /* Reading sk->sk_rxhash might incur an expensive cache line + * miss. + * + * TCP_ESTABLISHED does cover almost all states where RFS + * might be useful, and is cheaper [1] than testing : + * IPv4: inet_sk(sk)->inet_daddr + * IPv6: ipv6_addr_any(&sk->sk_v6_daddr) + * OR an additional socket flag + * [1] : sk_state and sk_prot are in the same cache line. + */ + if (sk->sk_state == TCP_ESTABLISHED) { + /* This READ_ONCE() is paired with the WRITE_ONCE() + * from sock_rps_save_rxhash() and sock_rps_reset_rxhash(). + */ + sock_rps_record_flow_hash(READ_ONCE(sk->sk_rxhash)); + } + } +#endif +} + +static inline void sock_rps_save_rxhash(struct sock *sk, + const struct sk_buff *skb) +{ +#ifdef CONFIG_RPS + /* The following WRITE_ONCE() is paired with the READ_ONCE() + * here, and another one in sock_rps_record_flow(). + */ + if (unlikely(READ_ONCE(sk->sk_rxhash) != skb->hash)) + WRITE_ONCE(sk->sk_rxhash, skb->hash); +#endif +} + +static inline void sock_rps_reset_rxhash(struct sock *sk) +{ +#ifdef CONFIG_RPS + /* Paired with READ_ONCE() in sock_rps_record_flow() */ + WRITE_ONCE(sk->sk_rxhash, 0); +#endif +} + +#define sk_wait_event(__sk, __timeo, __condition, __wait) \ + ({ int __rc; \ + __sk->sk_wait_pending++; \ + release_sock(__sk); \ + __rc = __condition; \ + if (!__rc) { \ + *(__timeo) = wait_woken(__wait, \ + TASK_INTERRUPTIBLE, \ + *(__timeo)); \ + } \ + sched_annotate_sleep(); \ + lock_sock(__sk); \ + __sk->sk_wait_pending--; \ + __rc = __condition; \ + __rc; \ + }) + +int sk_stream_wait_connect(struct sock *sk, long *timeo_p); +int sk_stream_wait_memory(struct sock *sk, long *timeo_p); +void sk_stream_wait_close(struct sock *sk, long timeo_p); +int sk_stream_error(struct sock *sk, int flags, int err); +void sk_stream_kill_queues(struct sock *sk); +void sk_set_memalloc(struct sock *sk); +void sk_clear_memalloc(struct sock *sk); + +void __sk_flush_backlog(struct sock *sk); + +static inline bool sk_flush_backlog(struct sock *sk) +{ + if (unlikely(READ_ONCE(sk->sk_backlog.tail))) { + __sk_flush_backlog(sk); + return true; + } + return false; +} + +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 smc_hashinfo; +struct module; + +/* + * caches using SLAB_TYPESAFE_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 + */ +struct proto { + void (*close)(struct sock *sk, + long timeout); + int (*pre_connect)(struct sock *sk, + struct sockaddr *uaddr, + int addr_len); + 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, + bool kern); + + 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, sockptr_t optval, + unsigned int optlen); + int (*getsockopt)(struct sock *sk, int level, + int optname, char __user *optval, + int __user *option); + void (*keepalive)(struct sock *sk, int valbool); +#ifdef CONFIG_COMPAT + int (*compat_ioctl)(struct sock *sk, + unsigned int cmd, unsigned long arg); +#endif + int (*sendmsg)(struct sock *sk, struct msghdr *msg, + size_t len); + int (*recvmsg)(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 *addr, int addr_len); + int (*bind_add)(struct sock *sk, + struct sockaddr *addr, int addr_len); + + int (*backlog_rcv) (struct sock *sk, + struct sk_buff *skb); + bool (*bpf_bypass_getsockopt)(int level, + int optname); + + void (*release_cb)(struct sock *sk); + + /* Keeping track of sk's, looking them up, and port selection methods. */ + int (*hash)(struct sock *sk); + void (*unhash)(struct sock *sk); + void (*rehash)(struct sock *sk); + int (*get_port)(struct sock *sk, unsigned short snum); + + /* Keeping track of sockets in use */ +#ifdef CONFIG_PROC_FS + unsigned int inuse_idx; +#endif + + bool (*stream_memory_free)(const struct sock *sk, int wake); + bool (*stream_memory_read)(const struct sock *sk); + /* Memory pressure */ + void (*enter_memory_pressure)(struct sock *sk); + void (*leave_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. + * Make sure to use READ_ONCE()/WRITE_ONCE() for all reads/writes. + * All the __sk_mem_schedule() is of this nature: accounting + * is strict, actions are advisory and have some latency. + */ + unsigned long *memory_pressure; + long *sysctl_mem; + + int *sysctl_wmem; + int *sysctl_rmem; + u32 sysctl_wmem_offset; + u32 sysctl_rmem_offset; + + int max_header; + bool no_autobind; + + struct kmem_cache *slab; + unsigned int obj_size; + slab_flags_t slab_flags; + unsigned int useroffset; /* Usercopy region offset */ + unsigned int usersize; /* Usercopy region size */ + + unsigned int __percpu *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; + struct smc_hashinfo *smc_hash; + } h; + + struct module *owner; + + char name[32]; + + struct list_head node; +#ifdef SOCK_REFCNT_DEBUG + atomic_t socks; +#endif + int (*diag_destroy)(struct sock *sk, int err); +} __randomize_layout; + +int proto_register(struct proto *prot, int alloc_slab); +void proto_unregister(struct proto *prot); +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 (refcount_read(&sk->sk_refcnt) != 1) + printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n", + sk->sk_prot->name, sk, refcount_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 */ + +static inline bool __sk_stream_memory_free(const struct sock *sk, int wake) +{ + if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf)) + return false; + + return sk->sk_prot->stream_memory_free ? + sk->sk_prot->stream_memory_free(sk, wake) : true; +} + +static inline bool sk_stream_memory_free(const struct sock *sk) +{ + return __sk_stream_memory_free(sk, 0); +} + +static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake) +{ + return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) && + __sk_stream_memory_free(sk, wake); +} + +static inline bool sk_stream_is_writeable(const struct sock *sk) +{ + return __sk_stream_is_writeable(sk, 0); +} + +static inline int sk_under_cgroup_hierarchy(struct sock *sk, + struct cgroup *ancestor) +{ +#ifdef CONFIG_SOCK_CGROUP_DATA + return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data), + ancestor); +#else + return -ENOTSUPP; +#endif +} + +static inline bool sk_has_memory_pressure(const struct sock *sk) +{ + return sk->sk_prot->memory_pressure != NULL; +} + +static inline bool sk_under_global_memory_pressure(const struct sock *sk) +{ + return sk->sk_prot->memory_pressure && + !!READ_ONCE(*sk->sk_prot->memory_pressure); +} + +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_memcg && + mem_cgroup_under_socket_pressure(sk->sk_memcg)) + return true; + + return !!READ_ONCE(*sk->sk_prot->memory_pressure); +} + +static inline long +sk_memory_allocated(const struct sock *sk) +{ + return atomic_long_read(sk->sk_prot->memory_allocated); +} + +static inline long +sk_memory_allocated_add(struct sock *sk, int amt) +{ + return atomic_long_add_return(amt, sk->sk_prot->memory_allocated); +} + +static inline void +sk_memory_allocated_sub(struct sock *sk, int amt) +{ + atomic_long_sub(amt, sk->sk_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 u64 +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 !!READ_ONCE(*prot->memory_pressure); +} + + +#ifdef CONFIG_PROC_FS +/* Called with local bh disabled */ +void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc); +int sock_prot_inuse_get(struct net *net, struct proto *proto); +int sock_inuse_get(struct net *net); +#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 int __sk_prot_rehash(struct sock *sk) +{ + sk->sk_prot->unhash(sk); + return sk->sk_prot->hash(sk); +} + +/* 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 + +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); +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); + +/* We used to have PAGE_SIZE here, but systems with 64KB pages + * do not necessarily have 16x time more memory than 4KB ones. + */ +#define SK_MEM_QUANTUM 4096 +#define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM) +#define SK_MEM_SEND 0 +#define SK_MEM_RECV 1 + +/* sysctl_mem values are in pages, we convert them in SK_MEM_QUANTUM units */ +static inline long sk_prot_mem_limits(const struct sock *sk, int index) +{ + long val = READ_ONCE(sk->sk_prot->sysctl_mem[index]); + +#if PAGE_SIZE > SK_MEM_QUANTUM + val <<= PAGE_SHIFT - SK_MEM_QUANTUM_SHIFT; +#elif PAGE_SIZE < SK_MEM_QUANTUM + val >>= SK_MEM_QUANTUM_SHIFT - PAGE_SHIFT; +#endif + return val; +} + +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) +{ + int delta; + + if (!sk_has_account(sk)) + return true; + delta = size - sk->sk_forward_alloc; + return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_SEND); +} + +static inline bool +sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size) +{ + int delta; + + if (!sk_has_account(sk)) + return true; + delta = size - sk->sk_forward_alloc; + return delta <= 0 || __sk_mem_schedule(sk, delta, 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; + + /* Avoid a possible overflow. + * TCP send queues can make this happen, if sk_mem_reclaim() + * is not called and more than 2 GBytes are released at once. + * + * If we reach 2 MBytes, reclaim 1 MBytes right now, there is + * no need to hold that much forward allocation anyway. + */ + if (unlikely(sk->sk_forward_alloc >= 1 << 21)) + __sk_mem_reclaim(sk, 1 << 20); +} + +DECLARE_STATIC_KEY_FALSE(tcp_tx_skb_cache_key); +static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb) +{ + sk_wmem_queued_add(sk, -skb->truesize); + sk_mem_uncharge(sk, skb->truesize); + if (static_branch_unlikely(&tcp_tx_skb_cache_key) && + !sk->sk_tx_skb_cache && !skb_cloned(skb)) { + skb_ext_reset(skb); + skb_zcopy_clear(skb, true); + sk->sk_tx_skb_cache = skb; + return; + } + __kfree_skb(skb); +} + +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, _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 *sk) +{ + return lockdep_is_held(&sk->sk_lock) || + lockdep_is_held(&sk->sk_lock.slock); +} +#endif + +void lock_sock_nested(struct sock *sk, int subclass); + +static inline void lock_sock(struct sock *sk) +{ + lock_sock_nested(sk, 0); +} + +void __release_sock(struct sock *sk); +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)) + +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); +} + +/* 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. + */ + +static inline void sock_owned_by_me(const struct sock *sk) +{ +#ifdef CONFIG_LOCKDEP + WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks); +#endif +} + +static inline bool sock_owned_by_user(const struct sock *sk) +{ + sock_owned_by_me(sk); + return sk->sk_lock.owned; +} + +static inline bool sock_owned_by_user_nocheck(const struct sock *sk) +{ + return sk->sk_lock.owned; +} + +/* no reclassification while locks are held */ +static inline bool sock_allow_reclassification(const struct sock *csk) +{ + struct sock *sk = (struct sock *)csk; + + return !sk->sk_lock.owned && !spin_is_locked(&sk->sk_lock.slock); +} + +struct sock *sk_alloc(struct net *net, int family, gfp_t priority, + struct proto *prot, int kern); +void sk_free(struct sock *sk); +void sk_destruct(struct sock *sk); +struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority); +void sk_free_unlock_clone(struct sock *sk); + +struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, + gfp_t priority); +void __sock_wfree(struct sk_buff *skb); +void sock_wfree(struct sk_buff *skb); +struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size, + gfp_t priority); +void skb_orphan_partial(struct sk_buff *skb); +void sock_rfree(struct sk_buff *skb); +void sock_efree(struct sk_buff *skb); +#ifdef CONFIG_INET +void sock_edemux(struct sk_buff *skb); +void sock_pfree(struct sk_buff *skb); +#else +#define sock_edemux sock_efree +#endif + +int sock_setsockopt(struct socket *sock, int level, int op, + sockptr_t optval, unsigned int optlen); + +int sock_getsockopt(struct socket *sock, int level, int op, + char __user *optval, int __user *optlen); +int sock_gettstamp(struct socket *sock, void __user *userstamp, + bool timeval, bool time32); +struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, + int noblock, int *errcode); +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); +void *sock_kmalloc(struct sock *sk, int size, gfp_t priority); +void sock_kfree_s(struct sock *sk, void *mem, int size); +void sock_kzfree_s(struct sock *sk, void *mem, int size); +void sk_send_sigurg(struct sock *sk); + +struct sockcm_cookie { + u64 transmit_time; + u32 mark; + u16 tsflags; +}; + +static inline void sockcm_init(struct sockcm_cookie *sockc, + const struct sock *sk) +{ + *sockc = (struct sockcm_cookie) { .tsflags = sk->sk_tsflags }; +} + +int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg, + struct sockcm_cookie *sockc); +int sock_cmsg_send(struct sock *sk, struct msghdr *msg, + struct sockcm_cookie *sockc); + +/* + * Functions to fill in entries in struct proto_ops when a protocol + * does not implement a particular function. + */ +int sock_no_bind(struct socket *, struct sockaddr *, int); +int sock_no_connect(struct socket *, struct sockaddr *, int, int); +int sock_no_socketpair(struct socket *, struct socket *); +int sock_no_accept(struct socket *, struct socket *, int, bool); +int sock_no_getname(struct socket *, struct sockaddr *, int); +int sock_no_ioctl(struct socket *, unsigned int, unsigned long); +int sock_no_listen(struct socket *, int); +int sock_no_shutdown(struct socket *, int); +int sock_no_sendmsg(struct socket *, struct msghdr *, size_t); +int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len); +int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int); +int sock_no_mmap(struct file *file, struct socket *sock, + struct vm_area_struct *vma); +ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, + size_t size, int flags); +ssize_t sock_no_sendpage_locked(struct sock *sk, 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. + */ +int sock_common_getsockopt(struct socket *sock, int level, int optname, + char __user *optval, int __user *optlen); +int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, + int flags); +int sock_common_setsockopt(struct socket *sock, int level, int optname, + sockptr_t optval, unsigned int optlen); + +void sk_common_release(struct sock *sk); + +/* + * Default socket callbacks and setup code + */ + +/* Initialise core socket variables using an explicit uid. */ +void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid); + +/* Initialise core socket variables. + * Assumes struct socket *sock is embedded in a struct socket_alloc. + */ +void sock_init_data(struct socket *sock, struct sock *sk); + +/* + * 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 (refcount_dec_and_test(&sk->sk_refcnt)) + sk_free(sk); +} +/* Generic version of sock_put(), dealing with all sockets + * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...) + */ +void sock_gen_put(struct sock *sk); + +int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested, + unsigned int trim_cap, bool refcounted); +static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb, + const int nested) +{ + return __sk_receive_skb(sk, skb, nested, 1, true); +} + +static inline void sk_tx_queue_set(struct sock *sk, int tx_queue) +{ + /* sk_tx_queue_mapping accept only upto a 16-bit value */ + if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX)) + return; + /* Paired with READ_ONCE() in sk_tx_queue_get() and + * other WRITE_ONCE() because socket lock might be not held. + */ + WRITE_ONCE(sk->sk_tx_queue_mapping, tx_queue); +} + +#define NO_QUEUE_MAPPING USHRT_MAX + +static inline void sk_tx_queue_clear(struct sock *sk) +{ + /* Paired with READ_ONCE() in sk_tx_queue_get() and + * other WRITE_ONCE() because socket lock might be not held. + */ + WRITE_ONCE(sk->sk_tx_queue_mapping, NO_QUEUE_MAPPING); +} + +static inline int sk_tx_queue_get(const struct sock *sk) +{ + if (sk) { + /* Paired with WRITE_ONCE() in sk_tx_queue_clear() + * and sk_tx_queue_set(). + */ + int val = READ_ONCE(sk->sk_tx_queue_mapping); + + if (val != NO_QUEUE_MAPPING) + return val; + } + return -1; +} + +static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb) +{ +#ifdef CONFIG_XPS + if (skb_rx_queue_recorded(skb)) { + u16 rx_queue = skb_get_rx_queue(skb); + + if (WARN_ON_ONCE(rx_queue == NO_QUEUE_MAPPING)) + return; + + sk->sk_rx_queue_mapping = rx_queue; + } +#endif +} + +static inline void sk_rx_queue_clear(struct sock *sk) +{ +#ifdef CONFIG_XPS + sk->sk_rx_queue_mapping = NO_QUEUE_MAPPING; +#endif +} + +#ifdef CONFIG_XPS +static inline int sk_rx_queue_get(const struct sock *sk) +{ + if (sk && sk->sk_rx_queue_mapping != NO_QUEUE_MAPPING) + return sk->sk_rx_queue_mapping; + + return -1; +} +#endif + +static inline void sk_set_socket(struct sock *sk, struct socket *sock) +{ + 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) +{ + WARN_ON(parent->sk); + write_lock_bh(&sk->sk_callback_lock); + rcu_assign_pointer(sk->sk_wq, &parent->wq); + parent->sk = sk; + sk_set_socket(sk, parent); + sk->sk_uid = SOCK_INODE(parent)->i_uid; + security_sock_graft(sk, parent); + write_unlock_bh(&sk->sk_callback_lock); +} + +kuid_t sock_i_uid(struct sock *sk); +unsigned long __sock_i_ino(struct sock *sk); +unsigned long sock_i_ino(struct sock *sk); + +static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk) +{ + return sk ? sk->sk_uid : make_kuid(net->user_ns, 0); +} + +static inline u32 net_tx_rndhash(void) +{ + u32 v = prandom_u32(); + + return v ?: 1; +} + +static inline void sk_set_txhash(struct sock *sk) +{ + /* This pairs with READ_ONCE() in skb_set_hash_from_sk() */ + WRITE_ONCE(sk->sk_txhash, net_tx_rndhash()); +} + +static inline bool sk_rethink_txhash(struct sock *sk) +{ + if (sk->sk_txhash) { + sk_set_txhash(sk); + return true; + } + return false; +} + +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; +} + +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_tx_queue_clear(sk); + WRITE_ONCE(sk->sk_dst_pending_confirm, 0); + } + } +} + +static inline void dst_negative_advice(struct sock *sk) +{ + sk_rethink_txhash(sk); + __dst_negative_advice(sk); +} + +static inline void +__sk_dst_set(struct sock *sk, struct dst_entry *dst) +{ + struct dst_entry *old_dst; + + sk_tx_queue_clear(sk); + WRITE_ONCE(sk->sk_dst_pending_confirm, 0); + old_dst = rcu_dereference_protected(sk->sk_dst_cache, + lockdep_sock_is_held(sk)); + 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); + WRITE_ONCE(sk->sk_dst_pending_confirm, 0); + old_dst = xchg((__force struct dst_entry **)&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); +} + +struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie); + +struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie); + +static inline void sk_dst_confirm(struct sock *sk) +{ + if (!READ_ONCE(sk->sk_dst_pending_confirm)) + WRITE_ONCE(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 (READ_ONCE(n->confirmed) != now) + WRITE_ONCE(n->confirmed, now); + if (sk && READ_ONCE(sk->sk_dst_pending_confirm)) + WRITE_ONCE(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); +} + +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, + struct iov_iter *from, char *to, + int copy, int offset) +{ + if (skb->ip_summed == CHECKSUM_NONE) { + __wsum csum = 0; + if (!csum_and_copy_from_iter_full(to, copy, &csum, from)) + return -EFAULT; + skb->csum = csum_block_add(skb->csum, csum, offset); + } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) { + if (!copy_from_iter_full_nocache(to, copy, from)) + return -EFAULT; + } else if (!copy_from_iter_full(to, copy, from)) + return -EFAULT; + + return 0; +} + +static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb, + struct iov_iter *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, struct iov_iter *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_wmem_queued_add(sk, copy); + sk_mem_charge(sk, copy); + return 0; +} + +/** + * sk_wmem_alloc_get - returns write allocations + * @sk: socket + * + * Return: sk_wmem_alloc minus initial offset of one + */ +static inline int sk_wmem_alloc_get(const struct sock *sk) +{ + return refcount_read(&sk->sk_wmem_alloc) - 1; +} + +/** + * sk_rmem_alloc_get - returns read allocations + * @sk: socket + * + * Return: 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 + * + * Return: 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); +} + +/** + * skwq_has_sleeper - check if there are any waiting processes + * @wq: struct socket_wq + * + * Return: true if socket_wq has waiting processes + * + * The purpose of the skwq_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 skwq_has_sleeper(struct socket_wq *wq) +{ + return wq && wq_has_sleeper(&wq->wait); +} + +/** + * sock_poll_wait - place memory barrier behind the poll_wait call. + * @filp: file + * @sock: socket to wait on + * @p: poll_table + * + * See the comments in the wq_has_sleeper function. + */ +static inline void sock_poll_wait(struct file *filp, struct socket *sock, + poll_table *p) +{ + if (!poll_does_not_wait(p)) { + poll_wait(filp, &sock->wq.wait, 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) +{ + /* This pairs with WRITE_ONCE() in sk_set_txhash() */ + u32 txhash = READ_ONCE(sk->sk_txhash); + + if (txhash) { + skb->l4_hash = 1; + skb->hash = txhash; + } +} + +void skb_set_owner_w(struct sk_buff *skb, struct sock *sk); + +/* + * 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_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); +} + +static inline __must_check bool skb_set_owner_sk_safe(struct sk_buff *skb, struct sock *sk) +{ + if (sk && refcount_inc_not_zero(&sk->sk_refcnt)) { + skb_orphan(skb); + skb->destructor = sock_efree; + skb->sk = sk; + return true; + } + return false; +} + +static inline struct sk_buff *skb_clone_and_charge_r(struct sk_buff *skb, struct sock *sk) +{ + skb = skb_clone(skb, sk_gfp_mask(sk, GFP_ATOMIC)); + if (skb) { + if (sk_rmem_schedule(sk, skb, skb->truesize)) { + skb_set_owner_r(skb, sk); + return skb; + } + __kfree_skb(skb); + } + return NULL; +} + +void sk_reset_timer(struct sock *sk, struct timer_list *timer, + unsigned long expires); + +void sk_stop_timer(struct sock *sk, struct timer_list *timer); + +void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer); + +int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue, + 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); +int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); + +int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb); +struct sk_buff *sock_dequeue_err_skb(struct sock *sk); + +/* + * Recover an error report and clear atomically + */ + +static inline int sock_error(struct sock *sk) +{ + int err; + + /* Avoid an atomic operation for the common case. + * This is racy since another cpu/thread can change sk_err under us. + */ + if (likely(data_race(!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 - refcount_read(&sk->sk_wmem_alloc); + if (amt < 0) + amt = 0; + } + return amt; +} + +/* Note: + * We use sk->sk_wq_raw, from contexts knowing this + * pointer is not NULL and cannot disappear/change. + */ +static inline void sk_set_bit(int nr, struct sock *sk) +{ + if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) && + !sock_flag(sk, SOCK_FASYNC)) + return; + + set_bit(nr, &sk->sk_wq_raw->flags); +} + +static inline void sk_clear_bit(int nr, struct sock *sk) +{ + if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) && + !sock_flag(sk, SOCK_FASYNC)) + return; + + clear_bit(nr, &sk->sk_wq_raw->flags); +} + +static inline void sk_wake_async(const struct sock *sk, int how, int band) +{ + if (sock_flag(sk, SOCK_FASYNC)) { + rcu_read_lock(); + sock_wake_async(rcu_dereference(sk->sk_wq), how, band); + rcu_read_unlock(); + } +} + +/* 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) +{ + u32 val; + + if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) + return; + + val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1); + + WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF)); +} + +struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp, + bool force_schedule); + +/** + * sk_page_frag - return an appropriate page_frag + * @sk: socket + * + * Use the per task page_frag instead of the per socket one for + * optimization when we know that we're in process context and own + * everything that's associated with %current. + * + * Both direct reclaim and page faults can nest inside other + * socket operations and end up recursing into sk_page_frag() + * while it's already in use: explicitly avoid task page_frag + * usage if the caller is potentially doing any of them. + * This assumes that page fault handlers use the GFP_NOFS flags. + * + * Return: a per task page_frag if context allows that, + * otherwise a per socket one. + */ +static inline struct page_frag *sk_page_frag(struct sock *sk) +{ + if ((sk->sk_allocation & (__GFP_DIRECT_RECLAIM | __GFP_MEMALLOC | __GFP_FS)) == + (__GFP_DIRECT_RECLAIM | __GFP_FS)) + return ¤t->task_frag; + + return &sk->sk_frag; +} + +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 refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(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) +{ + int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len); + + return v ?: 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; +} + +struct sock_skb_cb { + u32 dropcount; +}; + +/* Store sock_skb_cb at the end of skb->cb[] so protocol families + * using skb->cb[] would keep using it directly and utilize its + * alignement guarantee. + */ +#define SOCK_SKB_CB_OFFSET ((sizeof_field(struct sk_buff, cb) - \ + sizeof(struct sock_skb_cb))) + +#define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \ + SOCK_SKB_CB_OFFSET)) + +#define sock_skb_cb_check_size(size) \ + BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET) + +static inline void +sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb) +{ + SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ? + atomic_read(&sk->sk_drops) : 0; +} + +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); +} + +static inline ktime_t sock_read_timestamp(struct sock *sk) +{ +#if BITS_PER_LONG==32 + unsigned int seq; + ktime_t kt; + + do { + seq = read_seqbegin(&sk->sk_stamp_seq); + kt = sk->sk_stamp; + } while (read_seqretry(&sk->sk_stamp_seq, seq)); + + return kt; +#else + return READ_ONCE(sk->sk_stamp); +#endif +} + +static inline void sock_write_timestamp(struct sock *sk, ktime_t kt) +{ +#if BITS_PER_LONG==32 + write_seqlock(&sk->sk_stamp_seq); + sk->sk_stamp = kt; + write_sequnlock(&sk->sk_stamp_seq); +#else + WRITE_ONCE(sk->sk_stamp, kt); +#endif +} + +void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk, + struct sk_buff *skb); +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 && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) || + (hwtstamps->hwtstamp && + (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE))) + __sock_recv_timestamp(msg, sk, skb); + else + sock_write_timestamp(sk, kt); + + if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid) + __sock_recv_wifi_status(msg, sk, skb); +} + +void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk, + struct sk_buff *skb); + +#define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC) +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) + + if (sk->sk_flags & FLAGS_TS_OR_DROPS || sk->sk_tsflags & TSFLAGS_ANY) + __sock_recv_ts_and_drops(msg, sk, skb); + else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP))) + sock_write_timestamp(sk, skb->tstamp); + else if (unlikely(sock_read_timestamp(sk) == SK_DEFAULT_STAMP)) + sock_write_timestamp(sk, 0); +} + +void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags); + +/** + * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped + * @sk: socket sending this packet + * @tsflags: timestamping flags to use + * @tx_flags: completed with instructions for time stamping + * @tskey: filled in with next sk_tskey (not for TCP, which uses seqno) + * + * Note: callers should take care of initial ``*tx_flags`` value (usually 0) + */ +static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags, + __u8 *tx_flags, __u32 *tskey) +{ + if (unlikely(tsflags)) { + __sock_tx_timestamp(tsflags, tx_flags); + if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey && + tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK) + *tskey = sk->sk_tskey++; + } + if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS))) + *tx_flags |= SKBTX_WIFI_STATUS; +} + +static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags, + __u8 *tx_flags) +{ + _sock_tx_timestamp(sk, tsflags, tx_flags, NULL); +} + +static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags) +{ + _sock_tx_timestamp(skb->sk, tsflags, &skb_shinfo(skb)->tx_flags, + &skb_shinfo(skb)->tskey); +} + +DECLARE_STATIC_KEY_FALSE(tcp_rx_skb_cache_key); +/** + * 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); + if (static_branch_unlikely(&tcp_rx_skb_cache_key) && + !sk->sk_rx_skb_cache) { + sk->sk_rx_skb_cache = skb; + skb_orphan(skb); + return; + } + __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); +} + +static inline bool +skb_sk_is_prefetched(struct sk_buff *skb) +{ +#ifdef CONFIG_INET + return skb->destructor == sock_pfree; +#else + return false; +#endif /* CONFIG_INET */ +} + +/* This helper checks if a socket is a full socket, + * ie _not_ a timewait or request socket. + */ +static inline bool sk_fullsock(const struct sock *sk) +{ + return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV); +} + +static inline bool +sk_is_refcounted(struct sock *sk) +{ + /* Only full sockets have sk->sk_flags. */ + return !sk_fullsock(sk) || !sock_flag(sk, SOCK_RCU_FREE); +} + +/** + * skb_steal_sock - steal a socket from an sk_buff + * @skb: sk_buff to steal the socket from + * @refcounted: is set to true if the socket is reference-counted + */ +static inline struct sock * +skb_steal_sock(struct sk_buff *skb, bool *refcounted) +{ + if (skb->sk) { + struct sock *sk = skb->sk; + + *refcounted = true; + if (skb_sk_is_prefetched(skb)) + *refcounted = sk_is_refcounted(sk); + skb->destructor = NULL; + skb->sk = NULL; + return sk; + } + *refcounted = false; + return NULL; +} + +/* Checks if this SKB belongs to an HW offloaded socket + * and whether any SW fallbacks are required based on dev. + * Check decrypted mark in case skb_orphan() cleared socket. + */ +static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb, + struct net_device *dev) +{ +#ifdef CONFIG_SOCK_VALIDATE_XMIT + struct sock *sk = skb->sk; + + if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) { + skb = sk->sk_validate_xmit_skb(sk, dev, skb); +#ifdef CONFIG_TLS_DEVICE + } else if (unlikely(skb->decrypted)) { + pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n"); + kfree_skb(skb); + skb = NULL; +#endif + } +#endif + + return skb; +} + +/* This helper checks if a socket is a LISTEN or NEW_SYN_RECV + * SYNACK messages can be attached to either ones (depending on SYNCOOKIE) + */ +static inline bool sk_listener(const struct sock *sk) +{ + return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV); +} + +void sock_enable_timestamp(struct sock *sk, enum sock_flags flag); +int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level, + int type); + +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); + +void sk_get_meminfo(const struct sock *sk, u32 *meminfo); + +/* Take into consideration the size of the struct sk_buff overhead in the + * determination of these values, since that is non-constant across + * platforms. This makes socket queueing behavior and performance + * not depend upon such differences. + */ +#define _SK_MEM_PACKETS 256 +#define _SK_MEM_OVERHEAD SKB_TRUESIZE(256) +#define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) +#define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) + +extern __u32 sysctl_wmem_max; +extern __u32 sysctl_rmem_max; + +extern int sysctl_tstamp_allow_data; +extern int sysctl_optmem_max; + +extern __u32 sysctl_wmem_default; +extern __u32 sysctl_rmem_default; + +#define SKB_FRAG_PAGE_ORDER get_order(32768) +DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key); + +static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto) +{ + /* Does this proto have per netns sysctl_wmem ? */ + if (proto->sysctl_wmem_offset) + return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset)); + + return READ_ONCE(*proto->sysctl_wmem); +} + +static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto) +{ + /* Does this proto have per netns sysctl_rmem ? */ + if (proto->sysctl_rmem_offset) + return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset)); + + return READ_ONCE(*proto->sysctl_rmem); +} + +/* Default TCP Small queue budget is ~1 ms of data (1sec >> 10) + * Some wifi drivers need to tweak it to get more chunks. + * They can use this helper from their ndo_start_xmit() + */ +static inline void sk_pacing_shift_update(struct sock *sk, int val) +{ + if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val) + return; + WRITE_ONCE(sk->sk_pacing_shift, val); +} + +/* if a socket is bound to a device, check that the given device + * index is either the same or that the socket is bound to an L3 + * master device and the given device index is also enslaved to + * that L3 master + */ +static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif) +{ + int mdif; + + if (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dif) + return true; + + mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif); + if (mdif && mdif == sk->sk_bound_dev_if) + return true; + + return false; +} + +void sock_def_readable(struct sock *sk); + +int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk); +void sock_enable_timestamps(struct sock *sk); +void sock_no_linger(struct sock *sk); +void sock_set_keepalive(struct sock *sk); +void sock_set_priority(struct sock *sk, u32 priority); +void sock_set_rcvbuf(struct sock *sk, int val); +void sock_set_mark(struct sock *sk, u32 val); +void sock_set_reuseaddr(struct sock *sk); +void sock_set_reuseport(struct sock *sk); +void sock_set_sndtimeo(struct sock *sk, s64 secs); + +int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len); + +#endif /* _SOCK_H */ |