xref: /linux/include/net/sock.h (revision f15e3b3ddb9fab1c1731b6154e2cd6573fb54c4d)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * INET		An implementation of the TCP/IP protocol suite for the LINUX
4  *		operating system.  INET is implemented using the  BSD Socket
5  *		interface as the means of communication with the user level.
6  *
7  *		Definitions for the AF_INET socket handler.
8  *
9  * Version:	@(#)sock.h	1.0.4	05/13/93
10  *
11  * Authors:	Ross Biro
12  *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
13  *		Corey Minyard <wf-rch!minyard@relay.EU.net>
14  *		Florian La Roche <flla@stud.uni-sb.de>
15  *
16  * Fixes:
17  *		Alan Cox	:	Volatiles in skbuff pointers. See
18  *					skbuff comments. May be overdone,
19  *					better to prove they can be removed
20  *					than the reverse.
21  *		Alan Cox	:	Added a zapped field for tcp to note
22  *					a socket is reset and must stay shut up
23  *		Alan Cox	:	New fields for options
24  *	Pauline Middelink	:	identd support
25  *		Alan Cox	:	Eliminate low level recv/recvfrom
26  *		David S. Miller	:	New socket lookup architecture.
27  *              Steve Whitehouse:       Default routines for sock_ops
28  *              Arnaldo C. Melo :	removed net_pinfo, tp_pinfo and made
29  *              			protinfo be just a void pointer, as the
30  *              			protocol specific parts were moved to
31  *              			respective headers and ipv4/v6, etc now
32  *              			use private slabcaches for its socks
33  *              Pedro Hortas	:	New flags field for socket options
34  */
35 #ifndef _SOCK_H
36 #define _SOCK_H
37 
38 #include <linux/hardirq.h>
39 #include <linux/kernel.h>
40 #include <linux/list.h>
41 #include <linux/list_nulls.h>
42 #include <linux/timer.h>
43 #include <linux/cache.h>
44 #include <linux/bitops.h>
45 #include <linux/lockdep.h>
46 #include <linux/netdevice.h>
47 #include <linux/skbuff.h>	/* struct sk_buff */
48 #include <linux/mm.h>
49 #include <linux/security.h>
50 #include <linux/slab.h>
51 #include <linux/uaccess.h>
52 #include <linux/page_counter.h>
53 #include <linux/memcontrol.h>
54 #include <linux/static_key.h>
55 #include <linux/sched.h>
56 #include <linux/wait.h>
57 #include <linux/cgroup-defs.h>
58 #include <linux/rbtree.h>
59 #include <linux/rculist_nulls.h>
60 #include <linux/poll.h>
61 #include <linux/sockptr.h>
62 #include <linux/indirect_call_wrapper.h>
63 #include <linux/atomic.h>
64 #include <linux/refcount.h>
65 #include <linux/llist.h>
66 #include <net/dst.h>
67 #include <net/checksum.h>
68 #include <net/tcp_states.h>
69 #include <linux/net_tstamp.h>
70 #include <net/l3mdev.h>
71 #include <uapi/linux/socket.h>
72 
73 /*
74  * This structure really needs to be cleaned up.
75  * Most of it is for TCP, and not used by any of
76  * the other protocols.
77  */
78 
79 /* This is the per-socket lock.  The spinlock provides a synchronization
80  * between user contexts and software interrupt processing, whereas the
81  * mini-semaphore synchronizes multiple users amongst themselves.
82  */
83 typedef struct {
84 	spinlock_t		slock;
85 	int			owned;
86 	wait_queue_head_t	wq;
87 	/*
88 	 * We express the mutex-alike socket_lock semantics
89 	 * to the lock validator by explicitly managing
90 	 * the slock as a lock variant (in addition to
91 	 * the slock itself):
92 	 */
93 #ifdef CONFIG_DEBUG_LOCK_ALLOC
94 	struct lockdep_map dep_map;
95 #endif
96 } socket_lock_t;
97 
98 struct sock;
99 struct proto;
100 struct net;
101 
102 typedef __u32 __bitwise __portpair;
103 typedef __u64 __bitwise __addrpair;
104 
105 /**
106  *	struct sock_common - minimal network layer representation of sockets
107  *	@skc_daddr: Foreign IPv4 addr
108  *	@skc_rcv_saddr: Bound local IPv4 addr
109  *	@skc_addrpair: 8-byte-aligned __u64 union of @skc_daddr & @skc_rcv_saddr
110  *	@skc_hash: hash value used with various protocol lookup tables
111  *	@skc_u16hashes: two u16 hash values used by UDP lookup tables
112  *	@skc_dport: placeholder for inet_dport/tw_dport
113  *	@skc_num: placeholder for inet_num/tw_num
114  *	@skc_portpair: __u32 union of @skc_dport & @skc_num
115  *	@skc_family: network address family
116  *	@skc_state: Connection state
117  *	@skc_reuse: %SO_REUSEADDR setting
118  *	@skc_reuseport: %SO_REUSEPORT setting
119  *	@skc_ipv6only: socket is IPV6 only
120  *	@skc_net_refcnt: socket is using net ref counting
121  *	@skc_bound_dev_if: bound device index if != 0
122  *	@skc_bind_node: bind hash linkage for various protocol lookup tables
123  *	@skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
124  *	@skc_prot: protocol handlers inside a network family
125  *	@skc_net: reference to the network namespace of this socket
126  *	@skc_v6_daddr: IPV6 destination address
127  *	@skc_v6_rcv_saddr: IPV6 source address
128  *	@skc_cookie: socket's cookie value
129  *	@skc_node: main hash linkage for various protocol lookup tables
130  *	@skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
131  *	@skc_tx_queue_mapping: tx queue number for this connection
132  *	@skc_rx_queue_mapping: rx queue number for this connection
133  *	@skc_flags: place holder for sk_flags
134  *		%SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
135  *		%SO_OOBINLINE settings, %SO_TIMESTAMPING settings
136  *	@skc_listener: connection request listener socket (aka rsk_listener)
137  *		[union with @skc_flags]
138  *	@skc_tw_dr: (aka tw_dr) ptr to &struct inet_timewait_death_row
139  *		[union with @skc_flags]
140  *	@skc_incoming_cpu: record/match cpu processing incoming packets
141  *	@skc_rcv_wnd: (aka rsk_rcv_wnd) TCP receive window size (possibly scaled)
142  *		[union with @skc_incoming_cpu]
143  *	@skc_tw_rcv_nxt: (aka tw_rcv_nxt) TCP window next expected seq number
144  *		[union with @skc_incoming_cpu]
145  *	@skc_refcnt: reference count
146  *
147  *	This is the minimal network layer representation of sockets, the header
148  *	for struct sock and struct inet_timewait_sock.
149  */
150 struct sock_common {
151 	union {
152 		__addrpair	skc_addrpair;
153 		struct {
154 			__be32	skc_daddr;
155 			__be32	skc_rcv_saddr;
156 		};
157 	};
158 	union  {
159 		unsigned int	skc_hash;
160 		__u16		skc_u16hashes[2];
161 	};
162 	/* skc_dport && skc_num must be grouped as well */
163 	union {
164 		__portpair	skc_portpair;
165 		struct {
166 			__be16	skc_dport;
167 			__u16	skc_num;
168 		};
169 	};
170 
171 	unsigned short		skc_family;
172 	volatile unsigned char	skc_state;
173 	unsigned char		skc_reuse:4;
174 	unsigned char		skc_reuseport:1;
175 	unsigned char		skc_ipv6only:1;
176 	unsigned char		skc_net_refcnt:1;
177 	int			skc_bound_dev_if;
178 	union {
179 		struct hlist_node	skc_bind_node;
180 		struct hlist_node	skc_portaddr_node;
181 	};
182 	struct proto		*skc_prot;
183 	possible_net_t		skc_net;
184 
185 #if IS_ENABLED(CONFIG_IPV6)
186 	struct in6_addr		skc_v6_daddr;
187 	struct in6_addr		skc_v6_rcv_saddr;
188 #endif
189 
190 	atomic64_t		skc_cookie;
191 
192 	/* following fields are padding to force
193 	 * offset(struct sock, sk_refcnt) == 128 on 64bit arches
194 	 * assuming IPV6 is enabled. We use this padding differently
195 	 * for different kind of 'sockets'
196 	 */
197 	union {
198 		unsigned long	skc_flags;
199 		struct sock	*skc_listener; /* request_sock */
200 		struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */
201 	};
202 	/*
203 	 * fields between dontcopy_begin/dontcopy_end
204 	 * are not copied in sock_copy()
205 	 */
206 	/* private: */
207 	int			skc_dontcopy_begin[0];
208 	/* public: */
209 	union {
210 		struct hlist_node	skc_node;
211 		struct hlist_nulls_node skc_nulls_node;
212 	};
213 	unsigned short		skc_tx_queue_mapping;
214 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
215 	unsigned short		skc_rx_queue_mapping;
216 #endif
217 	union {
218 		int		skc_incoming_cpu;
219 		u32		skc_rcv_wnd;
220 		u32		skc_tw_rcv_nxt; /* struct tcp_timewait_sock  */
221 	};
222 
223 	refcount_t		skc_refcnt;
224 	/* private: */
225 	int                     skc_dontcopy_end[0];
226 	union {
227 		u32		skc_rxhash;
228 		u32		skc_window_clamp;
229 		u32		skc_tw_snd_nxt; /* struct tcp_timewait_sock */
230 	};
231 	/* public: */
232 };
233 
234 struct bpf_local_storage;
235 struct sk_filter;
236 
237 /**
238   *	struct sock - network layer representation of sockets
239   *	@__sk_common: shared layout with inet_timewait_sock
240   *	@sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
241   *	@sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
242   *	@sk_lock:	synchronizer
243   *	@sk_kern_sock: True if sock is using kernel lock classes
244   *	@sk_rcvbuf: size of receive buffer in bytes
245   *	@sk_wq: sock wait queue and async head
246   *	@sk_rx_dst: receive input route used by early demux
247   *	@sk_rx_dst_ifindex: ifindex for @sk_rx_dst
248   *	@sk_rx_dst_cookie: cookie for @sk_rx_dst
249   *	@sk_dst_cache: destination cache
250   *	@sk_dst_pending_confirm: need to confirm neighbour
251   *	@sk_policy: flow policy
252   *	@sk_receive_queue: incoming packets
253   *	@sk_wmem_alloc: transmit queue bytes committed
254   *	@sk_tsq_flags: TCP Small Queues flags
255   *	@sk_write_queue: Packet sending queue
256   *	@sk_omem_alloc: "o" is "option" or "other"
257   *	@sk_wmem_queued: persistent queue size
258   *	@sk_forward_alloc: space allocated forward
259   *	@sk_reserved_mem: space reserved and non-reclaimable for the socket
260   *	@sk_napi_id: id of the last napi context to receive data for sk
261   *	@sk_ll_usec: usecs to busypoll when there is no data
262   *	@sk_allocation: allocation mode
263   *	@sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler)
264   *	@sk_pacing_status: Pacing status (requested, handled by sch_fq)
265   *	@sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE)
266   *	@sk_sndbuf: size of send buffer in bytes
267   *	@sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets
268   *	@sk_no_check_rx: allow zero checksum in RX packets
269   *	@sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
270   *	@sk_gso_disabled: if set, NETIF_F_GSO_MASK is forbidden.
271   *	@sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
272   *	@sk_gso_max_size: Maximum GSO segment size to build
273   *	@sk_gso_max_segs: Maximum number of GSO segments
274   *	@sk_pacing_shift: scaling factor for TCP Small Queues
275   *	@sk_lingertime: %SO_LINGER l_linger setting
276   *	@sk_backlog: always used with the per-socket spinlock held
277   *	@sk_callback_lock: used with the callbacks in the end of this struct
278   *	@sk_error_queue: rarely used
279   *	@sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
280   *			  IPV6_ADDRFORM for instance)
281   *	@sk_err: last error
282   *	@sk_err_soft: errors that don't cause failure but are the cause of a
283   *		      persistent failure not just 'timed out'
284   *	@sk_drops: raw/udp drops counter
285   *	@sk_ack_backlog: current listen backlog
286   *	@sk_max_ack_backlog: listen backlog set in listen()
287   *	@sk_uid: user id of owner
288   *	@sk_prefer_busy_poll: prefer busypolling over softirq processing
289   *	@sk_busy_poll_budget: napi processing budget when busypolling
290   *	@sk_priority: %SO_PRIORITY setting
291   *	@sk_type: socket type (%SOCK_STREAM, etc)
292   *	@sk_protocol: which protocol this socket belongs in this network family
293   *	@sk_peer_lock: lock protecting @sk_peer_pid and @sk_peer_cred
294   *	@sk_peer_pid: &struct pid for this socket's peer
295   *	@sk_peer_cred: %SO_PEERCRED setting
296   *	@sk_rcvlowat: %SO_RCVLOWAT setting
297   *	@sk_rcvtimeo: %SO_RCVTIMEO setting
298   *	@sk_sndtimeo: %SO_SNDTIMEO setting
299   *	@sk_txhash: computed flow hash for use on transmit
300   *	@sk_txrehash: enable TX hash rethink
301   *	@sk_filter: socket filtering instructions
302   *	@sk_timer: sock cleanup timer
303   *	@sk_stamp: time stamp of last packet received
304   *	@sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only
305   *	@sk_tsflags: SO_TIMESTAMPING flags
306   *	@sk_use_task_frag: allow sk_page_frag() to use current->task_frag.
307   *			   Sockets that can be used under memory reclaim should
308   *			   set this to false.
309   *	@sk_bind_phc: SO_TIMESTAMPING bind PHC index of PTP virtual clock
310   *	              for timestamping
311   *	@sk_tskey: counter to disambiguate concurrent tstamp requests
312   *	@sk_zckey: counter to order MSG_ZEROCOPY notifications
313   *	@sk_socket: Identd and reporting IO signals
314   *	@sk_user_data: RPC layer private data. Write-protected by @sk_callback_lock.
315   *	@sk_frag: cached page frag
316   *	@sk_peek_off: current peek_offset value
317   *	@sk_send_head: front of stuff to transmit
318   *	@tcp_rtx_queue: TCP re-transmit queue [union with @sk_send_head]
319   *	@sk_security: used by security modules
320   *	@sk_mark: generic packet mark
321   *	@sk_cgrp_data: cgroup data for this cgroup
322   *	@sk_memcg: this socket's memory cgroup association
323   *	@sk_write_pending: a write to stream socket waits to start
324   *	@sk_disconnects: number of disconnect operations performed on this sock
325   *	@sk_state_change: callback to indicate change in the state of the sock
326   *	@sk_data_ready: callback to indicate there is data to be processed
327   *	@sk_write_space: callback to indicate there is bf sending space available
328   *	@sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
329   *	@sk_backlog_rcv: callback to process the backlog
330   *	@sk_validate_xmit_skb: ptr to an optional validate function
331   *	@sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
332   *	@sk_reuseport_cb: reuseport group container
333   *	@sk_bpf_storage: ptr to cache and control for bpf_sk_storage
334   *	@sk_rcu: used during RCU grace period
335   *	@sk_clockid: clockid used by time-based scheduling (SO_TXTIME)
336   *	@sk_txtime_deadline_mode: set deadline mode for SO_TXTIME
337   *	@sk_txtime_report_errors: set report errors mode for SO_TXTIME
338   *	@sk_txtime_unused: unused txtime flags
339   *	@ns_tracker: tracker for netns reference
340   *	@sk_user_frags: xarray of pages the user is holding a reference on.
341   */
342 struct sock {
343 	/*
344 	 * Now struct inet_timewait_sock also uses sock_common, so please just
345 	 * don't add nothing before this first member (__sk_common) --acme
346 	 */
347 	struct sock_common	__sk_common;
348 #define sk_node			__sk_common.skc_node
349 #define sk_nulls_node		__sk_common.skc_nulls_node
350 #define sk_refcnt		__sk_common.skc_refcnt
351 #define sk_tx_queue_mapping	__sk_common.skc_tx_queue_mapping
352 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
353 #define sk_rx_queue_mapping	__sk_common.skc_rx_queue_mapping
354 #endif
355 
356 #define sk_dontcopy_begin	__sk_common.skc_dontcopy_begin
357 #define sk_dontcopy_end		__sk_common.skc_dontcopy_end
358 #define sk_hash			__sk_common.skc_hash
359 #define sk_portpair		__sk_common.skc_portpair
360 #define sk_num			__sk_common.skc_num
361 #define sk_dport		__sk_common.skc_dport
362 #define sk_addrpair		__sk_common.skc_addrpair
363 #define sk_daddr		__sk_common.skc_daddr
364 #define sk_rcv_saddr		__sk_common.skc_rcv_saddr
365 #define sk_family		__sk_common.skc_family
366 #define sk_state		__sk_common.skc_state
367 #define sk_reuse		__sk_common.skc_reuse
368 #define sk_reuseport		__sk_common.skc_reuseport
369 #define sk_ipv6only		__sk_common.skc_ipv6only
370 #define sk_net_refcnt		__sk_common.skc_net_refcnt
371 #define sk_bound_dev_if		__sk_common.skc_bound_dev_if
372 #define sk_bind_node		__sk_common.skc_bind_node
373 #define sk_prot			__sk_common.skc_prot
374 #define sk_net			__sk_common.skc_net
375 #define sk_v6_daddr		__sk_common.skc_v6_daddr
376 #define sk_v6_rcv_saddr	__sk_common.skc_v6_rcv_saddr
377 #define sk_cookie		__sk_common.skc_cookie
378 #define sk_incoming_cpu		__sk_common.skc_incoming_cpu
379 #define sk_flags		__sk_common.skc_flags
380 #define sk_rxhash		__sk_common.skc_rxhash
381 
382 	__cacheline_group_begin(sock_write_rx);
383 
384 	atomic_t		sk_drops;
385 	__s32			sk_peek_off;
386 	struct sk_buff_head	sk_error_queue;
387 	struct sk_buff_head	sk_receive_queue;
388 	/*
389 	 * The backlog queue is special, it is always used with
390 	 * the per-socket spinlock held and requires low latency
391 	 * access. Therefore we special case it's implementation.
392 	 * Note : rmem_alloc is in this structure to fill a hole
393 	 * on 64bit arches, not because its logically part of
394 	 * backlog.
395 	 */
396 	struct {
397 		atomic_t	rmem_alloc;
398 		int		len;
399 		struct sk_buff	*head;
400 		struct sk_buff	*tail;
401 	} sk_backlog;
402 #define sk_rmem_alloc sk_backlog.rmem_alloc
403 
404 	__cacheline_group_end(sock_write_rx);
405 
406 	__cacheline_group_begin(sock_read_rx);
407 	/* early demux fields */
408 	struct dst_entry __rcu	*sk_rx_dst;
409 	int			sk_rx_dst_ifindex;
410 	u32			sk_rx_dst_cookie;
411 
412 #ifdef CONFIG_NET_RX_BUSY_POLL
413 	unsigned int		sk_ll_usec;
414 	unsigned int		sk_napi_id;
415 	u16			sk_busy_poll_budget;
416 	u8			sk_prefer_busy_poll;
417 #endif
418 	u8			sk_userlocks;
419 	int			sk_rcvbuf;
420 
421 	struct sk_filter __rcu	*sk_filter;
422 	union {
423 		struct socket_wq __rcu	*sk_wq;
424 		/* private: */
425 		struct socket_wq	*sk_wq_raw;
426 		/* public: */
427 	};
428 
429 	void			(*sk_data_ready)(struct sock *sk);
430 	long			sk_rcvtimeo;
431 	int			sk_rcvlowat;
432 	__cacheline_group_end(sock_read_rx);
433 
434 	__cacheline_group_begin(sock_read_rxtx);
435 	int			sk_err;
436 	struct socket		*sk_socket;
437 	struct mem_cgroup	*sk_memcg;
438 #ifdef CONFIG_XFRM
439 	struct xfrm_policy __rcu *sk_policy[2];
440 #endif
441 	__cacheline_group_end(sock_read_rxtx);
442 
443 	__cacheline_group_begin(sock_write_rxtx);
444 	socket_lock_t		sk_lock;
445 	u32			sk_reserved_mem;
446 	int			sk_forward_alloc;
447 	u32			sk_tsflags;
448 	__cacheline_group_end(sock_write_rxtx);
449 
450 	__cacheline_group_begin(sock_write_tx);
451 	int			sk_write_pending;
452 	atomic_t		sk_omem_alloc;
453 	int			sk_sndbuf;
454 
455 	int			sk_wmem_queued;
456 	refcount_t		sk_wmem_alloc;
457 	unsigned long		sk_tsq_flags;
458 	union {
459 		struct sk_buff	*sk_send_head;
460 		struct rb_root	tcp_rtx_queue;
461 	};
462 	struct sk_buff_head	sk_write_queue;
463 	u32			sk_dst_pending_confirm;
464 	u32			sk_pacing_status; /* see enum sk_pacing */
465 	struct page_frag	sk_frag;
466 	struct timer_list	sk_timer;
467 
468 	unsigned long		sk_pacing_rate; /* bytes per second */
469 	atomic_t		sk_zckey;
470 	atomic_t		sk_tskey;
471 	__cacheline_group_end(sock_write_tx);
472 
473 	__cacheline_group_begin(sock_read_tx);
474 	unsigned long		sk_max_pacing_rate;
475 	long			sk_sndtimeo;
476 	u32			sk_priority;
477 	u32			sk_mark;
478 	struct dst_entry __rcu	*sk_dst_cache;
479 	netdev_features_t	sk_route_caps;
480 #ifdef CONFIG_SOCK_VALIDATE_XMIT
481 	struct sk_buff*		(*sk_validate_xmit_skb)(struct sock *sk,
482 							struct net_device *dev,
483 							struct sk_buff *skb);
484 #endif
485 	u16			sk_gso_type;
486 	u16			sk_gso_max_segs;
487 	unsigned int		sk_gso_max_size;
488 	gfp_t			sk_allocation;
489 	u32			sk_txhash;
490 	u8			sk_pacing_shift;
491 	bool			sk_use_task_frag;
492 	__cacheline_group_end(sock_read_tx);
493 
494 	/*
495 	 * Because of non atomicity rules, all
496 	 * changes are protected by socket lock.
497 	 */
498 	u8			sk_gso_disabled : 1,
499 				sk_kern_sock : 1,
500 				sk_no_check_tx : 1,
501 				sk_no_check_rx : 1;
502 	u8			sk_shutdown;
503 	u16			sk_type;
504 	u16			sk_protocol;
505 	unsigned long	        sk_lingertime;
506 	struct proto		*sk_prot_creator;
507 	rwlock_t		sk_callback_lock;
508 	int			sk_err_soft;
509 	u32			sk_ack_backlog;
510 	u32			sk_max_ack_backlog;
511 	kuid_t			sk_uid;
512 	spinlock_t		sk_peer_lock;
513 	int			sk_bind_phc;
514 	struct pid		*sk_peer_pid;
515 	const struct cred	*sk_peer_cred;
516 
517 	ktime_t			sk_stamp;
518 #if BITS_PER_LONG==32
519 	seqlock_t		sk_stamp_seq;
520 #endif
521 	int			sk_disconnects;
522 
523 	u8			sk_txrehash;
524 	u8			sk_clockid;
525 	u8			sk_txtime_deadline_mode : 1,
526 				sk_txtime_report_errors : 1,
527 				sk_txtime_unused : 6;
528 
529 	void			*sk_user_data;
530 #ifdef CONFIG_SECURITY
531 	void			*sk_security;
532 #endif
533 	struct sock_cgroup_data	sk_cgrp_data;
534 	void			(*sk_state_change)(struct sock *sk);
535 	void			(*sk_write_space)(struct sock *sk);
536 	void			(*sk_error_report)(struct sock *sk);
537 	int			(*sk_backlog_rcv)(struct sock *sk,
538 						  struct sk_buff *skb);
539 	void                    (*sk_destruct)(struct sock *sk);
540 	struct sock_reuseport __rcu	*sk_reuseport_cb;
541 #ifdef CONFIG_BPF_SYSCALL
542 	struct bpf_local_storage __rcu	*sk_bpf_storage;
543 #endif
544 	struct rcu_head		sk_rcu;
545 	netns_tracker		ns_tracker;
546 	struct xarray		sk_user_frags;
547 };
548 
549 struct sock_bh_locked {
550 	struct sock *sock;
551 	local_lock_t bh_lock;
552 };
553 
554 enum sk_pacing {
555 	SK_PACING_NONE		= 0,
556 	SK_PACING_NEEDED	= 1,
557 	SK_PACING_FQ		= 2,
558 };
559 
560 /* flag bits in sk_user_data
561  *
562  * - SK_USER_DATA_NOCOPY:      Pointer stored in sk_user_data might
563  *   not be suitable for copying when cloning the socket. For instance,
564  *   it can point to a reference counted object. sk_user_data bottom
565  *   bit is set if pointer must not be copied.
566  *
567  * - SK_USER_DATA_BPF:         Mark whether sk_user_data field is
568  *   managed/owned by a BPF reuseport array. This bit should be set
569  *   when sk_user_data's sk is added to the bpf's reuseport_array.
570  *
571  * - SK_USER_DATA_PSOCK:       Mark whether pointer stored in
572  *   sk_user_data points to psock type. This bit should be set
573  *   when sk_user_data is assigned to a psock object.
574  */
575 #define SK_USER_DATA_NOCOPY	1UL
576 #define SK_USER_DATA_BPF	2UL
577 #define SK_USER_DATA_PSOCK	4UL
578 #define SK_USER_DATA_PTRMASK	~(SK_USER_DATA_NOCOPY | SK_USER_DATA_BPF |\
579 				  SK_USER_DATA_PSOCK)
580 
581 /**
582  * sk_user_data_is_nocopy - Test if sk_user_data pointer must not be copied
583  * @sk: socket
584  */
585 static inline bool sk_user_data_is_nocopy(const struct sock *sk)
586 {
587 	return ((uintptr_t)sk->sk_user_data & SK_USER_DATA_NOCOPY);
588 }
589 
590 #define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
591 
592 /**
593  * __locked_read_sk_user_data_with_flags - return the pointer
594  * only if argument flags all has been set in sk_user_data. Otherwise
595  * return NULL
596  *
597  * @sk: socket
598  * @flags: flag bits
599  *
600  * The caller must be holding sk->sk_callback_lock.
601  */
602 static inline void *
603 __locked_read_sk_user_data_with_flags(const struct sock *sk,
604 				      uintptr_t flags)
605 {
606 	uintptr_t sk_user_data =
607 		(uintptr_t)rcu_dereference_check(__sk_user_data(sk),
608 						 lockdep_is_held(&sk->sk_callback_lock));
609 
610 	WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK);
611 
612 	if ((sk_user_data & flags) == flags)
613 		return (void *)(sk_user_data & SK_USER_DATA_PTRMASK);
614 	return NULL;
615 }
616 
617 /**
618  * __rcu_dereference_sk_user_data_with_flags - return the pointer
619  * only if argument flags all has been set in sk_user_data. Otherwise
620  * return NULL
621  *
622  * @sk: socket
623  * @flags: flag bits
624  */
625 static inline void *
626 __rcu_dereference_sk_user_data_with_flags(const struct sock *sk,
627 					  uintptr_t flags)
628 {
629 	uintptr_t sk_user_data = (uintptr_t)rcu_dereference(__sk_user_data(sk));
630 
631 	WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK);
632 
633 	if ((sk_user_data & flags) == flags)
634 		return (void *)(sk_user_data & SK_USER_DATA_PTRMASK);
635 	return NULL;
636 }
637 
638 #define rcu_dereference_sk_user_data(sk)				\
639 	__rcu_dereference_sk_user_data_with_flags(sk, 0)
640 #define __rcu_assign_sk_user_data_with_flags(sk, ptr, flags)		\
641 ({									\
642 	uintptr_t __tmp1 = (uintptr_t)(ptr),				\
643 		  __tmp2 = (uintptr_t)(flags);				\
644 	WARN_ON_ONCE(__tmp1 & ~SK_USER_DATA_PTRMASK);			\
645 	WARN_ON_ONCE(__tmp2 & SK_USER_DATA_PTRMASK);			\
646 	rcu_assign_pointer(__sk_user_data((sk)),			\
647 			   __tmp1 | __tmp2);				\
648 })
649 #define rcu_assign_sk_user_data(sk, ptr)				\
650 	__rcu_assign_sk_user_data_with_flags(sk, ptr, 0)
651 
652 static inline
653 struct net *sock_net(const struct sock *sk)
654 {
655 	return read_pnet(&sk->sk_net);
656 }
657 
658 static inline
659 void sock_net_set(struct sock *sk, struct net *net)
660 {
661 	write_pnet(&sk->sk_net, net);
662 }
663 
664 /*
665  * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
666  * or not whether his port will be reused by someone else. SK_FORCE_REUSE
667  * on a socket means that the socket will reuse everybody else's port
668  * without looking at the other's sk_reuse value.
669  */
670 
671 #define SK_NO_REUSE	0
672 #define SK_CAN_REUSE	1
673 #define SK_FORCE_REUSE	2
674 
675 int sk_set_peek_off(struct sock *sk, int val);
676 
677 static inline int sk_peek_offset(const struct sock *sk, int flags)
678 {
679 	if (unlikely(flags & MSG_PEEK)) {
680 		return READ_ONCE(sk->sk_peek_off);
681 	}
682 
683 	return 0;
684 }
685 
686 static inline void sk_peek_offset_bwd(struct sock *sk, int val)
687 {
688 	s32 off = READ_ONCE(sk->sk_peek_off);
689 
690 	if (unlikely(off >= 0)) {
691 		off = max_t(s32, off - val, 0);
692 		WRITE_ONCE(sk->sk_peek_off, off);
693 	}
694 }
695 
696 static inline void sk_peek_offset_fwd(struct sock *sk, int val)
697 {
698 	sk_peek_offset_bwd(sk, -val);
699 }
700 
701 /*
702  * Hashed lists helper routines
703  */
704 static inline struct sock *sk_entry(const struct hlist_node *node)
705 {
706 	return hlist_entry(node, struct sock, sk_node);
707 }
708 
709 static inline struct sock *__sk_head(const struct hlist_head *head)
710 {
711 	return hlist_entry(head->first, struct sock, sk_node);
712 }
713 
714 static inline struct sock *sk_head(const struct hlist_head *head)
715 {
716 	return hlist_empty(head) ? NULL : __sk_head(head);
717 }
718 
719 static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
720 {
721 	return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
722 }
723 
724 static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
725 {
726 	return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
727 }
728 
729 static inline struct sock *sk_next(const struct sock *sk)
730 {
731 	return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node);
732 }
733 
734 static inline struct sock *sk_nulls_next(const struct sock *sk)
735 {
736 	return (!is_a_nulls(sk->sk_nulls_node.next)) ?
737 		hlist_nulls_entry(sk->sk_nulls_node.next,
738 				  struct sock, sk_nulls_node) :
739 		NULL;
740 }
741 
742 static inline bool sk_unhashed(const struct sock *sk)
743 {
744 	return hlist_unhashed(&sk->sk_node);
745 }
746 
747 static inline bool sk_hashed(const struct sock *sk)
748 {
749 	return !sk_unhashed(sk);
750 }
751 
752 static inline void sk_node_init(struct hlist_node *node)
753 {
754 	node->pprev = NULL;
755 }
756 
757 static inline void __sk_del_node(struct sock *sk)
758 {
759 	__hlist_del(&sk->sk_node);
760 }
761 
762 /* NB: equivalent to hlist_del_init_rcu */
763 static inline bool __sk_del_node_init(struct sock *sk)
764 {
765 	if (sk_hashed(sk)) {
766 		__sk_del_node(sk);
767 		sk_node_init(&sk->sk_node);
768 		return true;
769 	}
770 	return false;
771 }
772 
773 /* Grab socket reference count. This operation is valid only
774    when sk is ALREADY grabbed f.e. it is found in hash table
775    or a list and the lookup is made under lock preventing hash table
776    modifications.
777  */
778 
779 static __always_inline void sock_hold(struct sock *sk)
780 {
781 	refcount_inc(&sk->sk_refcnt);
782 }
783 
784 /* Ungrab socket in the context, which assumes that socket refcnt
785    cannot hit zero, f.e. it is true in context of any socketcall.
786  */
787 static __always_inline void __sock_put(struct sock *sk)
788 {
789 	refcount_dec(&sk->sk_refcnt);
790 }
791 
792 static inline bool sk_del_node_init(struct sock *sk)
793 {
794 	bool rc = __sk_del_node_init(sk);
795 
796 	if (rc) {
797 		/* paranoid for a while -acme */
798 		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
799 		__sock_put(sk);
800 	}
801 	return rc;
802 }
803 #define sk_del_node_init_rcu(sk)	sk_del_node_init(sk)
804 
805 static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
806 {
807 	if (sk_hashed(sk)) {
808 		hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
809 		return true;
810 	}
811 	return false;
812 }
813 
814 static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
815 {
816 	bool rc = __sk_nulls_del_node_init_rcu(sk);
817 
818 	if (rc) {
819 		/* paranoid for a while -acme */
820 		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
821 		__sock_put(sk);
822 	}
823 	return rc;
824 }
825 
826 static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
827 {
828 	hlist_add_head(&sk->sk_node, list);
829 }
830 
831 static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
832 {
833 	sock_hold(sk);
834 	__sk_add_node(sk, list);
835 }
836 
837 static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
838 {
839 	sock_hold(sk);
840 	if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
841 	    sk->sk_family == AF_INET6)
842 		hlist_add_tail_rcu(&sk->sk_node, list);
843 	else
844 		hlist_add_head_rcu(&sk->sk_node, list);
845 }
846 
847 static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list)
848 {
849 	sock_hold(sk);
850 	hlist_add_tail_rcu(&sk->sk_node, list);
851 }
852 
853 static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
854 {
855 	hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
856 }
857 
858 static inline void __sk_nulls_add_node_tail_rcu(struct sock *sk, struct hlist_nulls_head *list)
859 {
860 	hlist_nulls_add_tail_rcu(&sk->sk_nulls_node, list);
861 }
862 
863 static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
864 {
865 	sock_hold(sk);
866 	__sk_nulls_add_node_rcu(sk, list);
867 }
868 
869 static inline void __sk_del_bind_node(struct sock *sk)
870 {
871 	__hlist_del(&sk->sk_bind_node);
872 }
873 
874 static inline void sk_add_bind_node(struct sock *sk,
875 					struct hlist_head *list)
876 {
877 	hlist_add_head(&sk->sk_bind_node, list);
878 }
879 
880 #define sk_for_each(__sk, list) \
881 	hlist_for_each_entry(__sk, list, sk_node)
882 #define sk_for_each_rcu(__sk, list) \
883 	hlist_for_each_entry_rcu(__sk, list, sk_node)
884 #define sk_nulls_for_each(__sk, node, list) \
885 	hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
886 #define sk_nulls_for_each_rcu(__sk, node, list) \
887 	hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
888 #define sk_for_each_from(__sk) \
889 	hlist_for_each_entry_from(__sk, sk_node)
890 #define sk_nulls_for_each_from(__sk, node) \
891 	if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
892 		hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
893 #define sk_for_each_safe(__sk, tmp, list) \
894 	hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
895 #define sk_for_each_bound(__sk, list) \
896 	hlist_for_each_entry(__sk, list, sk_bind_node)
897 #define sk_for_each_bound_safe(__sk, tmp, list) \
898 	hlist_for_each_entry_safe(__sk, tmp, list, sk_bind_node)
899 
900 /**
901  * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset
902  * @tpos:	the type * to use as a loop cursor.
903  * @pos:	the &struct hlist_node to use as a loop cursor.
904  * @head:	the head for your list.
905  * @offset:	offset of hlist_node within the struct.
906  *
907  */
908 #define sk_for_each_entry_offset_rcu(tpos, pos, head, offset)		       \
909 	for (pos = rcu_dereference(hlist_first_rcu(head));		       \
910 	     pos != NULL &&						       \
911 		({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;});       \
912 	     pos = rcu_dereference(hlist_next_rcu(pos)))
913 
914 static inline struct user_namespace *sk_user_ns(const struct sock *sk)
915 {
916 	/* Careful only use this in a context where these parameters
917 	 * can not change and must all be valid, such as recvmsg from
918 	 * userspace.
919 	 */
920 	return sk->sk_socket->file->f_cred->user_ns;
921 }
922 
923 /* Sock flags */
924 enum sock_flags {
925 	SOCK_DEAD,
926 	SOCK_DONE,
927 	SOCK_URGINLINE,
928 	SOCK_KEEPOPEN,
929 	SOCK_LINGER,
930 	SOCK_DESTROY,
931 	SOCK_BROADCAST,
932 	SOCK_TIMESTAMP,
933 	SOCK_ZAPPED,
934 	SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
935 	SOCK_DBG, /* %SO_DEBUG setting */
936 	SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
937 	SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
938 	SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
939 	SOCK_MEMALLOC, /* VM depends on this socket for swapping */
940 	SOCK_TIMESTAMPING_RX_SOFTWARE,  /* %SOF_TIMESTAMPING_RX_SOFTWARE */
941 	SOCK_FASYNC, /* fasync() active */
942 	SOCK_RXQ_OVFL,
943 	SOCK_ZEROCOPY, /* buffers from userspace */
944 	SOCK_WIFI_STATUS, /* push wifi status to userspace */
945 	SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
946 		     * Will use last 4 bytes of packet sent from
947 		     * user-space instead.
948 		     */
949 	SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
950 	SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
951 	SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */
952 	SOCK_TXTIME,
953 	SOCK_XDP, /* XDP is attached */
954 	SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */
955 	SOCK_RCVMARK, /* Receive SO_MARK  ancillary data with packet */
956 };
957 
958 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
959 /*
960  * The highest bit of sk_tsflags is reserved for kernel-internal
961  * SOCKCM_FLAG_TS_OPT_ID. There is a check in core/sock.c to control that
962  * SOF_TIMESTAMPING* values do not reach this reserved area
963  */
964 #define SOCKCM_FLAG_TS_OPT_ID	BIT(31)
965 
966 static inline void sock_copy_flags(struct sock *nsk, const struct sock *osk)
967 {
968 	nsk->sk_flags = osk->sk_flags;
969 }
970 
971 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
972 {
973 	__set_bit(flag, &sk->sk_flags);
974 }
975 
976 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
977 {
978 	__clear_bit(flag, &sk->sk_flags);
979 }
980 
981 static inline void sock_valbool_flag(struct sock *sk, enum sock_flags bit,
982 				     int valbool)
983 {
984 	if (valbool)
985 		sock_set_flag(sk, bit);
986 	else
987 		sock_reset_flag(sk, bit);
988 }
989 
990 static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
991 {
992 	return test_bit(flag, &sk->sk_flags);
993 }
994 
995 #ifdef CONFIG_NET
996 DECLARE_STATIC_KEY_FALSE(memalloc_socks_key);
997 static inline int sk_memalloc_socks(void)
998 {
999 	return static_branch_unlikely(&memalloc_socks_key);
1000 }
1001 
1002 void __receive_sock(struct file *file);
1003 #else
1004 
1005 static inline int sk_memalloc_socks(void)
1006 {
1007 	return 0;
1008 }
1009 
1010 static inline void __receive_sock(struct file *file)
1011 { }
1012 #endif
1013 
1014 static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask)
1015 {
1016 	return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC);
1017 }
1018 
1019 static inline void sk_acceptq_removed(struct sock *sk)
1020 {
1021 	WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1);
1022 }
1023 
1024 static inline void sk_acceptq_added(struct sock *sk)
1025 {
1026 	WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1);
1027 }
1028 
1029 /* Note: If you think the test should be:
1030  *	return READ_ONCE(sk->sk_ack_backlog) >= READ_ONCE(sk->sk_max_ack_backlog);
1031  * Then please take a look at commit 64a146513f8f ("[NET]: Revert incorrect accept queue backlog changes.")
1032  */
1033 static inline bool sk_acceptq_is_full(const struct sock *sk)
1034 {
1035 	return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(sk->sk_max_ack_backlog);
1036 }
1037 
1038 /*
1039  * Compute minimal free write space needed to queue new packets.
1040  */
1041 static inline int sk_stream_min_wspace(const struct sock *sk)
1042 {
1043 	return READ_ONCE(sk->sk_wmem_queued) >> 1;
1044 }
1045 
1046 static inline int sk_stream_wspace(const struct sock *sk)
1047 {
1048 	return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued);
1049 }
1050 
1051 static inline void sk_wmem_queued_add(struct sock *sk, int val)
1052 {
1053 	WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val);
1054 }
1055 
1056 static inline void sk_forward_alloc_add(struct sock *sk, int val)
1057 {
1058 	/* Paired with lockless reads of sk->sk_forward_alloc */
1059 	WRITE_ONCE(sk->sk_forward_alloc, sk->sk_forward_alloc + val);
1060 }
1061 
1062 void sk_stream_write_space(struct sock *sk);
1063 
1064 /* OOB backlog add */
1065 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
1066 {
1067 	/* dont let skb dst not refcounted, we are going to leave rcu lock */
1068 	skb_dst_force(skb);
1069 
1070 	if (!sk->sk_backlog.tail)
1071 		WRITE_ONCE(sk->sk_backlog.head, skb);
1072 	else
1073 		sk->sk_backlog.tail->next = skb;
1074 
1075 	WRITE_ONCE(sk->sk_backlog.tail, skb);
1076 	skb->next = NULL;
1077 }
1078 
1079 /*
1080  * Take into account size of receive queue and backlog queue
1081  * Do not take into account this skb truesize,
1082  * to allow even a single big packet to come.
1083  */
1084 static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
1085 {
1086 	unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
1087 
1088 	return qsize > limit;
1089 }
1090 
1091 /* The per-socket spinlock must be held here. */
1092 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
1093 					      unsigned int limit)
1094 {
1095 	if (sk_rcvqueues_full(sk, limit))
1096 		return -ENOBUFS;
1097 
1098 	/*
1099 	 * If the skb was allocated from pfmemalloc reserves, only
1100 	 * allow SOCK_MEMALLOC sockets to use it as this socket is
1101 	 * helping free memory
1102 	 */
1103 	if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC))
1104 		return -ENOMEM;
1105 
1106 	__sk_add_backlog(sk, skb);
1107 	sk->sk_backlog.len += skb->truesize;
1108 	return 0;
1109 }
1110 
1111 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
1112 
1113 INDIRECT_CALLABLE_DECLARE(int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb));
1114 INDIRECT_CALLABLE_DECLARE(int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb));
1115 
1116 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
1117 {
1118 	if (sk_memalloc_socks() && skb_pfmemalloc(skb))
1119 		return __sk_backlog_rcv(sk, skb);
1120 
1121 	return INDIRECT_CALL_INET(sk->sk_backlog_rcv,
1122 				  tcp_v6_do_rcv,
1123 				  tcp_v4_do_rcv,
1124 				  sk, skb);
1125 }
1126 
1127 static inline void sk_incoming_cpu_update(struct sock *sk)
1128 {
1129 	int cpu = raw_smp_processor_id();
1130 
1131 	if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu))
1132 		WRITE_ONCE(sk->sk_incoming_cpu, cpu);
1133 }
1134 
1135 
1136 static inline void sock_rps_save_rxhash(struct sock *sk,
1137 					const struct sk_buff *skb)
1138 {
1139 #ifdef CONFIG_RPS
1140 	/* The following WRITE_ONCE() is paired with the READ_ONCE()
1141 	 * here, and another one in sock_rps_record_flow().
1142 	 */
1143 	if (unlikely(READ_ONCE(sk->sk_rxhash) != skb->hash))
1144 		WRITE_ONCE(sk->sk_rxhash, skb->hash);
1145 #endif
1146 }
1147 
1148 static inline void sock_rps_reset_rxhash(struct sock *sk)
1149 {
1150 #ifdef CONFIG_RPS
1151 	/* Paired with READ_ONCE() in sock_rps_record_flow() */
1152 	WRITE_ONCE(sk->sk_rxhash, 0);
1153 #endif
1154 }
1155 
1156 #define sk_wait_event(__sk, __timeo, __condition, __wait)		\
1157 	({	int __rc, __dis = __sk->sk_disconnects;			\
1158 		release_sock(__sk);					\
1159 		__rc = __condition;					\
1160 		if (!__rc) {						\
1161 			*(__timeo) = wait_woken(__wait,			\
1162 						TASK_INTERRUPTIBLE,	\
1163 						*(__timeo));		\
1164 		}							\
1165 		sched_annotate_sleep();					\
1166 		lock_sock(__sk);					\
1167 		__rc = __dis == __sk->sk_disconnects ? __condition : -EPIPE; \
1168 		__rc;							\
1169 	})
1170 
1171 int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
1172 int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
1173 void sk_stream_wait_close(struct sock *sk, long timeo_p);
1174 int sk_stream_error(struct sock *sk, int flags, int err);
1175 void sk_stream_kill_queues(struct sock *sk);
1176 void sk_set_memalloc(struct sock *sk);
1177 void sk_clear_memalloc(struct sock *sk);
1178 
1179 void __sk_flush_backlog(struct sock *sk);
1180 
1181 static inline bool sk_flush_backlog(struct sock *sk)
1182 {
1183 	if (unlikely(READ_ONCE(sk->sk_backlog.tail))) {
1184 		__sk_flush_backlog(sk);
1185 		return true;
1186 	}
1187 	return false;
1188 }
1189 
1190 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb);
1191 
1192 struct request_sock_ops;
1193 struct timewait_sock_ops;
1194 struct inet_hashinfo;
1195 struct raw_hashinfo;
1196 struct smc_hashinfo;
1197 struct module;
1198 struct sk_psock;
1199 
1200 /*
1201  * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes
1202  * un-modified. Special care is taken when initializing object to zero.
1203  */
1204 static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1205 {
1206 	if (offsetof(struct sock, sk_node.next) != 0)
1207 		memset(sk, 0, offsetof(struct sock, sk_node.next));
1208 	memset(&sk->sk_node.pprev, 0,
1209 	       size - offsetof(struct sock, sk_node.pprev));
1210 }
1211 
1212 struct proto_accept_arg {
1213 	int flags;
1214 	int err;
1215 	int is_empty;
1216 	bool kern;
1217 };
1218 
1219 /* Networking protocol blocks we attach to sockets.
1220  * socket layer -> transport layer interface
1221  */
1222 struct proto {
1223 	void			(*close)(struct sock *sk,
1224 					long timeout);
1225 	int			(*pre_connect)(struct sock *sk,
1226 					struct sockaddr *uaddr,
1227 					int addr_len);
1228 	int			(*connect)(struct sock *sk,
1229 					struct sockaddr *uaddr,
1230 					int addr_len);
1231 	int			(*disconnect)(struct sock *sk, int flags);
1232 
1233 	struct sock *		(*accept)(struct sock *sk,
1234 					  struct proto_accept_arg *arg);
1235 
1236 	int			(*ioctl)(struct sock *sk, int cmd,
1237 					 int *karg);
1238 	int			(*init)(struct sock *sk);
1239 	void			(*destroy)(struct sock *sk);
1240 	void			(*shutdown)(struct sock *sk, int how);
1241 	int			(*setsockopt)(struct sock *sk, int level,
1242 					int optname, sockptr_t optval,
1243 					unsigned int optlen);
1244 	int			(*getsockopt)(struct sock *sk, int level,
1245 					int optname, char __user *optval,
1246 					int __user *option);
1247 	void			(*keepalive)(struct sock *sk, int valbool);
1248 #ifdef CONFIG_COMPAT
1249 	int			(*compat_ioctl)(struct sock *sk,
1250 					unsigned int cmd, unsigned long arg);
1251 #endif
1252 	int			(*sendmsg)(struct sock *sk, struct msghdr *msg,
1253 					   size_t len);
1254 	int			(*recvmsg)(struct sock *sk, struct msghdr *msg,
1255 					   size_t len, int flags, int *addr_len);
1256 	void			(*splice_eof)(struct socket *sock);
1257 	int			(*bind)(struct sock *sk,
1258 					struct sockaddr *addr, int addr_len);
1259 	int			(*bind_add)(struct sock *sk,
1260 					struct sockaddr *addr, int addr_len);
1261 
1262 	int			(*backlog_rcv) (struct sock *sk,
1263 						struct sk_buff *skb);
1264 	bool			(*bpf_bypass_getsockopt)(int level,
1265 							 int optname);
1266 
1267 	void		(*release_cb)(struct sock *sk);
1268 
1269 	/* Keeping track of sk's, looking them up, and port selection methods. */
1270 	int			(*hash)(struct sock *sk);
1271 	void			(*unhash)(struct sock *sk);
1272 	void			(*rehash)(struct sock *sk);
1273 	int			(*get_port)(struct sock *sk, unsigned short snum);
1274 	void			(*put_port)(struct sock *sk);
1275 #ifdef CONFIG_BPF_SYSCALL
1276 	int			(*psock_update_sk_prot)(struct sock *sk,
1277 							struct sk_psock *psock,
1278 							bool restore);
1279 #endif
1280 
1281 	/* Keeping track of sockets in use */
1282 #ifdef CONFIG_PROC_FS
1283 	unsigned int		inuse_idx;
1284 #endif
1285 
1286 #if IS_ENABLED(CONFIG_MPTCP)
1287 	int			(*forward_alloc_get)(const struct sock *sk);
1288 #endif
1289 
1290 	bool			(*stream_memory_free)(const struct sock *sk, int wake);
1291 	bool			(*sock_is_readable)(struct sock *sk);
1292 	/* Memory pressure */
1293 	void			(*enter_memory_pressure)(struct sock *sk);
1294 	void			(*leave_memory_pressure)(struct sock *sk);
1295 	atomic_long_t		*memory_allocated;	/* Current allocated memory. */
1296 	int  __percpu		*per_cpu_fw_alloc;
1297 	struct percpu_counter	*sockets_allocated;	/* Current number of sockets. */
1298 
1299 	/*
1300 	 * Pressure flag: try to collapse.
1301 	 * Technical note: it is used by multiple contexts non atomically.
1302 	 * Make sure to use READ_ONCE()/WRITE_ONCE() for all reads/writes.
1303 	 * All the __sk_mem_schedule() is of this nature: accounting
1304 	 * is strict, actions are advisory and have some latency.
1305 	 */
1306 	unsigned long		*memory_pressure;
1307 	long			*sysctl_mem;
1308 
1309 	int			*sysctl_wmem;
1310 	int			*sysctl_rmem;
1311 	u32			sysctl_wmem_offset;
1312 	u32			sysctl_rmem_offset;
1313 
1314 	int			max_header;
1315 	bool			no_autobind;
1316 
1317 	struct kmem_cache	*slab;
1318 	unsigned int		obj_size;
1319 	unsigned int		ipv6_pinfo_offset;
1320 	slab_flags_t		slab_flags;
1321 	unsigned int		useroffset;	/* Usercopy region offset */
1322 	unsigned int		usersize;	/* Usercopy region size */
1323 
1324 	unsigned int __percpu	*orphan_count;
1325 
1326 	struct request_sock_ops	*rsk_prot;
1327 	struct timewait_sock_ops *twsk_prot;
1328 
1329 	union {
1330 		struct inet_hashinfo	*hashinfo;
1331 		struct udp_table	*udp_table;
1332 		struct raw_hashinfo	*raw_hash;
1333 		struct smc_hashinfo	*smc_hash;
1334 	} h;
1335 
1336 	struct module		*owner;
1337 
1338 	char			name[32];
1339 
1340 	struct list_head	node;
1341 	int			(*diag_destroy)(struct sock *sk, int err);
1342 } __randomize_layout;
1343 
1344 int proto_register(struct proto *prot, int alloc_slab);
1345 void proto_unregister(struct proto *prot);
1346 int sock_load_diag_module(int family, int protocol);
1347 
1348 INDIRECT_CALLABLE_DECLARE(bool tcp_stream_memory_free(const struct sock *sk, int wake));
1349 
1350 static inline int sk_forward_alloc_get(const struct sock *sk)
1351 {
1352 #if IS_ENABLED(CONFIG_MPTCP)
1353 	if (sk->sk_prot->forward_alloc_get)
1354 		return sk->sk_prot->forward_alloc_get(sk);
1355 #endif
1356 	return READ_ONCE(sk->sk_forward_alloc);
1357 }
1358 
1359 static inline bool __sk_stream_memory_free(const struct sock *sk, int wake)
1360 {
1361 	if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf))
1362 		return false;
1363 
1364 	return sk->sk_prot->stream_memory_free ?
1365 		INDIRECT_CALL_INET_1(sk->sk_prot->stream_memory_free,
1366 				     tcp_stream_memory_free, sk, wake) : true;
1367 }
1368 
1369 static inline bool sk_stream_memory_free(const struct sock *sk)
1370 {
1371 	return __sk_stream_memory_free(sk, 0);
1372 }
1373 
1374 static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake)
1375 {
1376 	return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
1377 	       __sk_stream_memory_free(sk, wake);
1378 }
1379 
1380 static inline bool sk_stream_is_writeable(const struct sock *sk)
1381 {
1382 	return __sk_stream_is_writeable(sk, 0);
1383 }
1384 
1385 static inline int sk_under_cgroup_hierarchy(struct sock *sk,
1386 					    struct cgroup *ancestor)
1387 {
1388 #ifdef CONFIG_SOCK_CGROUP_DATA
1389 	return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data),
1390 				    ancestor);
1391 #else
1392 	return -ENOTSUPP;
1393 #endif
1394 }
1395 
1396 #define SK_ALLOC_PERCPU_COUNTER_BATCH 16
1397 
1398 static inline void sk_sockets_allocated_dec(struct sock *sk)
1399 {
1400 	percpu_counter_add_batch(sk->sk_prot->sockets_allocated, -1,
1401 				 SK_ALLOC_PERCPU_COUNTER_BATCH);
1402 }
1403 
1404 static inline void sk_sockets_allocated_inc(struct sock *sk)
1405 {
1406 	percpu_counter_add_batch(sk->sk_prot->sockets_allocated, 1,
1407 				 SK_ALLOC_PERCPU_COUNTER_BATCH);
1408 }
1409 
1410 static inline u64
1411 sk_sockets_allocated_read_positive(struct sock *sk)
1412 {
1413 	return percpu_counter_read_positive(sk->sk_prot->sockets_allocated);
1414 }
1415 
1416 static inline int
1417 proto_sockets_allocated_sum_positive(struct proto *prot)
1418 {
1419 	return percpu_counter_sum_positive(prot->sockets_allocated);
1420 }
1421 
1422 #ifdef CONFIG_PROC_FS
1423 #define PROTO_INUSE_NR	64	/* should be enough for the first time */
1424 struct prot_inuse {
1425 	int all;
1426 	int val[PROTO_INUSE_NR];
1427 };
1428 
1429 static inline void sock_prot_inuse_add(const struct net *net,
1430 				       const struct proto *prot, int val)
1431 {
1432 	this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val);
1433 }
1434 
1435 static inline void sock_inuse_add(const struct net *net, int val)
1436 {
1437 	this_cpu_add(net->core.prot_inuse->all, val);
1438 }
1439 
1440 int sock_prot_inuse_get(struct net *net, struct proto *proto);
1441 int sock_inuse_get(struct net *net);
1442 #else
1443 static inline void sock_prot_inuse_add(const struct net *net,
1444 				       const struct proto *prot, int val)
1445 {
1446 }
1447 
1448 static inline void sock_inuse_add(const struct net *net, int val)
1449 {
1450 }
1451 #endif
1452 
1453 
1454 /* With per-bucket locks this operation is not-atomic, so that
1455  * this version is not worse.
1456  */
1457 static inline int __sk_prot_rehash(struct sock *sk)
1458 {
1459 	sk->sk_prot->unhash(sk);
1460 	return sk->sk_prot->hash(sk);
1461 }
1462 
1463 /* About 10 seconds */
1464 #define SOCK_DESTROY_TIME (10*HZ)
1465 
1466 /* Sockets 0-1023 can't be bound to unless you are superuser */
1467 #define PROT_SOCK	1024
1468 
1469 #define SHUTDOWN_MASK	3
1470 #define RCV_SHUTDOWN	1
1471 #define SEND_SHUTDOWN	2
1472 
1473 #define SOCK_BINDADDR_LOCK	4
1474 #define SOCK_BINDPORT_LOCK	8
1475 
1476 struct socket_alloc {
1477 	struct socket socket;
1478 	struct inode vfs_inode;
1479 };
1480 
1481 static inline struct socket *SOCKET_I(struct inode *inode)
1482 {
1483 	return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1484 }
1485 
1486 static inline struct inode *SOCK_INODE(struct socket *socket)
1487 {
1488 	return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1489 }
1490 
1491 /*
1492  * Functions for memory accounting
1493  */
1494 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind);
1495 int __sk_mem_schedule(struct sock *sk, int size, int kind);
1496 void __sk_mem_reduce_allocated(struct sock *sk, int amount);
1497 void __sk_mem_reclaim(struct sock *sk, int amount);
1498 
1499 #define SK_MEM_SEND	0
1500 #define SK_MEM_RECV	1
1501 
1502 /* sysctl_mem values are in pages */
1503 static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1504 {
1505 	return READ_ONCE(sk->sk_prot->sysctl_mem[index]);
1506 }
1507 
1508 static inline int sk_mem_pages(int amt)
1509 {
1510 	return (amt + PAGE_SIZE - 1) >> PAGE_SHIFT;
1511 }
1512 
1513 static inline bool sk_has_account(struct sock *sk)
1514 {
1515 	/* return true if protocol supports memory accounting */
1516 	return !!sk->sk_prot->memory_allocated;
1517 }
1518 
1519 static inline bool sk_wmem_schedule(struct sock *sk, int size)
1520 {
1521 	int delta;
1522 
1523 	if (!sk_has_account(sk))
1524 		return true;
1525 	delta = size - sk->sk_forward_alloc;
1526 	return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_SEND);
1527 }
1528 
1529 static inline bool
1530 sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
1531 {
1532 	int delta;
1533 
1534 	if (!sk_has_account(sk))
1535 		return true;
1536 	delta = size - sk->sk_forward_alloc;
1537 	return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_RECV) ||
1538 		skb_pfmemalloc(skb);
1539 }
1540 
1541 static inline int sk_unused_reserved_mem(const struct sock *sk)
1542 {
1543 	int unused_mem;
1544 
1545 	if (likely(!sk->sk_reserved_mem))
1546 		return 0;
1547 
1548 	unused_mem = sk->sk_reserved_mem - sk->sk_wmem_queued -
1549 			atomic_read(&sk->sk_rmem_alloc);
1550 
1551 	return unused_mem > 0 ? unused_mem : 0;
1552 }
1553 
1554 static inline void sk_mem_reclaim(struct sock *sk)
1555 {
1556 	int reclaimable;
1557 
1558 	if (!sk_has_account(sk))
1559 		return;
1560 
1561 	reclaimable = sk->sk_forward_alloc - sk_unused_reserved_mem(sk);
1562 
1563 	if (reclaimable >= (int)PAGE_SIZE)
1564 		__sk_mem_reclaim(sk, reclaimable);
1565 }
1566 
1567 static inline void sk_mem_reclaim_final(struct sock *sk)
1568 {
1569 	sk->sk_reserved_mem = 0;
1570 	sk_mem_reclaim(sk);
1571 }
1572 
1573 static inline void sk_mem_charge(struct sock *sk, int size)
1574 {
1575 	if (!sk_has_account(sk))
1576 		return;
1577 	sk_forward_alloc_add(sk, -size);
1578 }
1579 
1580 static inline void sk_mem_uncharge(struct sock *sk, int size)
1581 {
1582 	if (!sk_has_account(sk))
1583 		return;
1584 	sk_forward_alloc_add(sk, size);
1585 	sk_mem_reclaim(sk);
1586 }
1587 
1588 /*
1589  * Macro so as to not evaluate some arguments when
1590  * lockdep is not enabled.
1591  *
1592  * Mark both the sk_lock and the sk_lock.slock as a
1593  * per-address-family lock class.
1594  */
1595 #define sock_lock_init_class_and_name(sk, sname, skey, name, key)	\
1596 do {									\
1597 	sk->sk_lock.owned = 0;						\
1598 	init_waitqueue_head(&sk->sk_lock.wq);				\
1599 	spin_lock_init(&(sk)->sk_lock.slock);				\
1600 	debug_check_no_locks_freed((void *)&(sk)->sk_lock,		\
1601 			sizeof((sk)->sk_lock));				\
1602 	lockdep_set_class_and_name(&(sk)->sk_lock.slock,		\
1603 				(skey), (sname));				\
1604 	lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0);	\
1605 } while (0)
1606 
1607 static inline bool lockdep_sock_is_held(const struct sock *sk)
1608 {
1609 	return lockdep_is_held(&sk->sk_lock) ||
1610 	       lockdep_is_held(&sk->sk_lock.slock);
1611 }
1612 
1613 void lock_sock_nested(struct sock *sk, int subclass);
1614 
1615 static inline void lock_sock(struct sock *sk)
1616 {
1617 	lock_sock_nested(sk, 0);
1618 }
1619 
1620 void __lock_sock(struct sock *sk);
1621 void __release_sock(struct sock *sk);
1622 void release_sock(struct sock *sk);
1623 
1624 /* BH context may only use the following locking interface. */
1625 #define bh_lock_sock(__sk)	spin_lock(&((__sk)->sk_lock.slock))
1626 #define bh_lock_sock_nested(__sk) \
1627 				spin_lock_nested(&((__sk)->sk_lock.slock), \
1628 				SINGLE_DEPTH_NESTING)
1629 #define bh_unlock_sock(__sk)	spin_unlock(&((__sk)->sk_lock.slock))
1630 
1631 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock);
1632 
1633 /**
1634  * lock_sock_fast - fast version of lock_sock
1635  * @sk: socket
1636  *
1637  * This version should be used for very small section, where process won't block
1638  * return false if fast path is taken:
1639  *
1640  *   sk_lock.slock locked, owned = 0, BH disabled
1641  *
1642  * return true if slow path is taken:
1643  *
1644  *   sk_lock.slock unlocked, owned = 1, BH enabled
1645  */
1646 static inline bool lock_sock_fast(struct sock *sk)
1647 {
1648 	/* The sk_lock has mutex_lock() semantics here. */
1649 	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
1650 
1651 	return __lock_sock_fast(sk);
1652 }
1653 
1654 /* fast socket lock variant for caller already holding a [different] socket lock */
1655 static inline bool lock_sock_fast_nested(struct sock *sk)
1656 {
1657 	mutex_acquire(&sk->sk_lock.dep_map, SINGLE_DEPTH_NESTING, 0, _RET_IP_);
1658 
1659 	return __lock_sock_fast(sk);
1660 }
1661 
1662 /**
1663  * unlock_sock_fast - complement of lock_sock_fast
1664  * @sk: socket
1665  * @slow: slow mode
1666  *
1667  * fast unlock socket for user context.
1668  * If slow mode is on, we call regular release_sock()
1669  */
1670 static inline void unlock_sock_fast(struct sock *sk, bool slow)
1671 	__releases(&sk->sk_lock.slock)
1672 {
1673 	if (slow) {
1674 		release_sock(sk);
1675 		__release(&sk->sk_lock.slock);
1676 	} else {
1677 		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1678 		spin_unlock_bh(&sk->sk_lock.slock);
1679 	}
1680 }
1681 
1682 void sockopt_lock_sock(struct sock *sk);
1683 void sockopt_release_sock(struct sock *sk);
1684 bool sockopt_ns_capable(struct user_namespace *ns, int cap);
1685 bool sockopt_capable(int cap);
1686 
1687 /* Used by processes to "lock" a socket state, so that
1688  * interrupts and bottom half handlers won't change it
1689  * from under us. It essentially blocks any incoming
1690  * packets, so that we won't get any new data or any
1691  * packets that change the state of the socket.
1692  *
1693  * While locked, BH processing will add new packets to
1694  * the backlog queue.  This queue is processed by the
1695  * owner of the socket lock right before it is released.
1696  *
1697  * Since ~2.3.5 it is also exclusive sleep lock serializing
1698  * accesses from user process context.
1699  */
1700 
1701 static inline void sock_owned_by_me(const struct sock *sk)
1702 {
1703 #ifdef CONFIG_LOCKDEP
1704 	WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
1705 #endif
1706 }
1707 
1708 static inline void sock_not_owned_by_me(const struct sock *sk)
1709 {
1710 #ifdef CONFIG_LOCKDEP
1711 	WARN_ON_ONCE(lockdep_sock_is_held(sk) && debug_locks);
1712 #endif
1713 }
1714 
1715 static inline bool sock_owned_by_user(const struct sock *sk)
1716 {
1717 	sock_owned_by_me(sk);
1718 	return sk->sk_lock.owned;
1719 }
1720 
1721 static inline bool sock_owned_by_user_nocheck(const struct sock *sk)
1722 {
1723 	return sk->sk_lock.owned;
1724 }
1725 
1726 static inline void sock_release_ownership(struct sock *sk)
1727 {
1728 	DEBUG_NET_WARN_ON_ONCE(!sock_owned_by_user_nocheck(sk));
1729 	sk->sk_lock.owned = 0;
1730 
1731 	/* The sk_lock has mutex_unlock() semantics: */
1732 	mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1733 }
1734 
1735 /* no reclassification while locks are held */
1736 static inline bool sock_allow_reclassification(const struct sock *csk)
1737 {
1738 	struct sock *sk = (struct sock *)csk;
1739 
1740 	return !sock_owned_by_user_nocheck(sk) &&
1741 		!spin_is_locked(&sk->sk_lock.slock);
1742 }
1743 
1744 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1745 		      struct proto *prot, int kern);
1746 void sk_free(struct sock *sk);
1747 void sk_destruct(struct sock *sk);
1748 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
1749 void sk_free_unlock_clone(struct sock *sk);
1750 
1751 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1752 			     gfp_t priority);
1753 void __sock_wfree(struct sk_buff *skb);
1754 void sock_wfree(struct sk_buff *skb);
1755 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1756 			     gfp_t priority);
1757 void skb_orphan_partial(struct sk_buff *skb);
1758 void sock_rfree(struct sk_buff *skb);
1759 void sock_efree(struct sk_buff *skb);
1760 #ifdef CONFIG_INET
1761 void sock_edemux(struct sk_buff *skb);
1762 void sock_pfree(struct sk_buff *skb);
1763 
1764 static inline void skb_set_owner_edemux(struct sk_buff *skb, struct sock *sk)
1765 {
1766 	skb_orphan(skb);
1767 	if (refcount_inc_not_zero(&sk->sk_refcnt)) {
1768 		skb->sk = sk;
1769 		skb->destructor = sock_edemux;
1770 	}
1771 }
1772 #else
1773 #define sock_edemux sock_efree
1774 #endif
1775 
1776 int sk_setsockopt(struct sock *sk, int level, int optname,
1777 		  sockptr_t optval, unsigned int optlen);
1778 int sock_setsockopt(struct socket *sock, int level, int op,
1779 		    sockptr_t optval, unsigned int optlen);
1780 int do_sock_setsockopt(struct socket *sock, bool compat, int level,
1781 		       int optname, sockptr_t optval, int optlen);
1782 int do_sock_getsockopt(struct socket *sock, bool compat, int level,
1783 		       int optname, sockptr_t optval, sockptr_t optlen);
1784 
1785 int sk_getsockopt(struct sock *sk, int level, int optname,
1786 		  sockptr_t optval, sockptr_t optlen);
1787 int sock_gettstamp(struct socket *sock, void __user *userstamp,
1788 		   bool timeval, bool time32);
1789 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1790 				     unsigned long data_len, int noblock,
1791 				     int *errcode, int max_page_order);
1792 
1793 static inline struct sk_buff *sock_alloc_send_skb(struct sock *sk,
1794 						  unsigned long size,
1795 						  int noblock, int *errcode)
1796 {
1797 	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
1798 }
1799 
1800 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
1801 void sock_kfree_s(struct sock *sk, void *mem, int size);
1802 void sock_kzfree_s(struct sock *sk, void *mem, int size);
1803 void sk_send_sigurg(struct sock *sk);
1804 
1805 static inline void sock_replace_proto(struct sock *sk, struct proto *proto)
1806 {
1807 	if (sk->sk_socket)
1808 		clear_bit(SOCK_SUPPORT_ZC, &sk->sk_socket->flags);
1809 	WRITE_ONCE(sk->sk_prot, proto);
1810 }
1811 
1812 struct sockcm_cookie {
1813 	u64 transmit_time;
1814 	u32 mark;
1815 	u32 tsflags;
1816 	u32 ts_opt_id;
1817 };
1818 
1819 static inline void sockcm_init(struct sockcm_cookie *sockc,
1820 			       const struct sock *sk)
1821 {
1822 	*sockc = (struct sockcm_cookie) {
1823 		.tsflags = READ_ONCE(sk->sk_tsflags)
1824 	};
1825 }
1826 
1827 int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
1828 		     struct sockcm_cookie *sockc);
1829 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1830 		   struct sockcm_cookie *sockc);
1831 
1832 /*
1833  * Functions to fill in entries in struct proto_ops when a protocol
1834  * does not implement a particular function.
1835  */
1836 int sock_no_bind(struct socket *, struct sockaddr *, int);
1837 int sock_no_connect(struct socket *, struct sockaddr *, int, int);
1838 int sock_no_socketpair(struct socket *, struct socket *);
1839 int sock_no_accept(struct socket *, struct socket *, struct proto_accept_arg *);
1840 int sock_no_getname(struct socket *, struct sockaddr *, int);
1841 int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
1842 int sock_no_listen(struct socket *, int);
1843 int sock_no_shutdown(struct socket *, int);
1844 int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
1845 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
1846 int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
1847 int sock_no_mmap(struct file *file, struct socket *sock,
1848 		 struct vm_area_struct *vma);
1849 
1850 /*
1851  * Functions to fill in entries in struct proto_ops when a protocol
1852  * uses the inet style.
1853  */
1854 int sock_common_getsockopt(struct socket *sock, int level, int optname,
1855 				  char __user *optval, int __user *optlen);
1856 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1857 			int flags);
1858 int sock_common_setsockopt(struct socket *sock, int level, int optname,
1859 			   sockptr_t optval, unsigned int optlen);
1860 
1861 void sk_common_release(struct sock *sk);
1862 
1863 /*
1864  *	Default socket callbacks and setup code
1865  */
1866 
1867 /* Initialise core socket variables using an explicit uid. */
1868 void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid);
1869 
1870 /* Initialise core socket variables.
1871  * Assumes struct socket *sock is embedded in a struct socket_alloc.
1872  */
1873 void sock_init_data(struct socket *sock, struct sock *sk);
1874 
1875 /*
1876  * Socket reference counting postulates.
1877  *
1878  * * Each user of socket SHOULD hold a reference count.
1879  * * Each access point to socket (an hash table bucket, reference from a list,
1880  *   running timer, skb in flight MUST hold a reference count.
1881  * * When reference count hits 0, it means it will never increase back.
1882  * * When reference count hits 0, it means that no references from
1883  *   outside exist to this socket and current process on current CPU
1884  *   is last user and may/should destroy this socket.
1885  * * sk_free is called from any context: process, BH, IRQ. When
1886  *   it is called, socket has no references from outside -> sk_free
1887  *   may release descendant resources allocated by the socket, but
1888  *   to the time when it is called, socket is NOT referenced by any
1889  *   hash tables, lists etc.
1890  * * Packets, delivered from outside (from network or from another process)
1891  *   and enqueued on receive/error queues SHOULD NOT grab reference count,
1892  *   when they sit in queue. Otherwise, packets will leak to hole, when
1893  *   socket is looked up by one cpu and unhasing is made by another CPU.
1894  *   It is true for udp/raw, netlink (leak to receive and error queues), tcp
1895  *   (leak to backlog). Packet socket does all the processing inside
1896  *   BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1897  *   use separate SMP lock, so that they are prone too.
1898  */
1899 
1900 /* Ungrab socket and destroy it, if it was the last reference. */
1901 static inline void sock_put(struct sock *sk)
1902 {
1903 	if (refcount_dec_and_test(&sk->sk_refcnt))
1904 		sk_free(sk);
1905 }
1906 /* Generic version of sock_put(), dealing with all sockets
1907  * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
1908  */
1909 void sock_gen_put(struct sock *sk);
1910 
1911 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested,
1912 		     unsigned int trim_cap, bool refcounted);
1913 static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1914 				 const int nested)
1915 {
1916 	return __sk_receive_skb(sk, skb, nested, 1, true);
1917 }
1918 
1919 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1920 {
1921 	/* sk_tx_queue_mapping accept only upto a 16-bit value */
1922 	if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX))
1923 		return;
1924 	/* Paired with READ_ONCE() in sk_tx_queue_get() and
1925 	 * other WRITE_ONCE() because socket lock might be not held.
1926 	 */
1927 	WRITE_ONCE(sk->sk_tx_queue_mapping, tx_queue);
1928 }
1929 
1930 #define NO_QUEUE_MAPPING	USHRT_MAX
1931 
1932 static inline void sk_tx_queue_clear(struct sock *sk)
1933 {
1934 	/* Paired with READ_ONCE() in sk_tx_queue_get() and
1935 	 * other WRITE_ONCE() because socket lock might be not held.
1936 	 */
1937 	WRITE_ONCE(sk->sk_tx_queue_mapping, NO_QUEUE_MAPPING);
1938 }
1939 
1940 static inline int sk_tx_queue_get(const struct sock *sk)
1941 {
1942 	if (sk) {
1943 		/* Paired with WRITE_ONCE() in sk_tx_queue_clear()
1944 		 * and sk_tx_queue_set().
1945 		 */
1946 		int val = READ_ONCE(sk->sk_tx_queue_mapping);
1947 
1948 		if (val != NO_QUEUE_MAPPING)
1949 			return val;
1950 	}
1951 	return -1;
1952 }
1953 
1954 static inline void __sk_rx_queue_set(struct sock *sk,
1955 				     const struct sk_buff *skb,
1956 				     bool force_set)
1957 {
1958 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1959 	if (skb_rx_queue_recorded(skb)) {
1960 		u16 rx_queue = skb_get_rx_queue(skb);
1961 
1962 		if (force_set ||
1963 		    unlikely(READ_ONCE(sk->sk_rx_queue_mapping) != rx_queue))
1964 			WRITE_ONCE(sk->sk_rx_queue_mapping, rx_queue);
1965 	}
1966 #endif
1967 }
1968 
1969 static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb)
1970 {
1971 	__sk_rx_queue_set(sk, skb, true);
1972 }
1973 
1974 static inline void sk_rx_queue_update(struct sock *sk, const struct sk_buff *skb)
1975 {
1976 	__sk_rx_queue_set(sk, skb, false);
1977 }
1978 
1979 static inline void sk_rx_queue_clear(struct sock *sk)
1980 {
1981 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1982 	WRITE_ONCE(sk->sk_rx_queue_mapping, NO_QUEUE_MAPPING);
1983 #endif
1984 }
1985 
1986 static inline int sk_rx_queue_get(const struct sock *sk)
1987 {
1988 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1989 	if (sk) {
1990 		int res = READ_ONCE(sk->sk_rx_queue_mapping);
1991 
1992 		if (res != NO_QUEUE_MAPPING)
1993 			return res;
1994 	}
1995 #endif
1996 
1997 	return -1;
1998 }
1999 
2000 static inline void sk_set_socket(struct sock *sk, struct socket *sock)
2001 {
2002 	sk->sk_socket = sock;
2003 }
2004 
2005 static inline wait_queue_head_t *sk_sleep(struct sock *sk)
2006 {
2007 	BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
2008 	return &rcu_dereference_raw(sk->sk_wq)->wait;
2009 }
2010 /* Detach socket from process context.
2011  * Announce socket dead, detach it from wait queue and inode.
2012  * Note that parent inode held reference count on this struct sock,
2013  * we do not release it in this function, because protocol
2014  * probably wants some additional cleanups or even continuing
2015  * to work with this socket (TCP).
2016  */
2017 static inline void sock_orphan(struct sock *sk)
2018 {
2019 	write_lock_bh(&sk->sk_callback_lock);
2020 	sock_set_flag(sk, SOCK_DEAD);
2021 	sk_set_socket(sk, NULL);
2022 	sk->sk_wq  = NULL;
2023 	write_unlock_bh(&sk->sk_callback_lock);
2024 }
2025 
2026 static inline void sock_graft(struct sock *sk, struct socket *parent)
2027 {
2028 	WARN_ON(parent->sk);
2029 	write_lock_bh(&sk->sk_callback_lock);
2030 	rcu_assign_pointer(sk->sk_wq, &parent->wq);
2031 	parent->sk = sk;
2032 	sk_set_socket(sk, parent);
2033 	sk->sk_uid = SOCK_INODE(parent)->i_uid;
2034 	security_sock_graft(sk, parent);
2035 	write_unlock_bh(&sk->sk_callback_lock);
2036 }
2037 
2038 kuid_t sock_i_uid(struct sock *sk);
2039 unsigned long __sock_i_ino(struct sock *sk);
2040 unsigned long sock_i_ino(struct sock *sk);
2041 
2042 static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk)
2043 {
2044 	return sk ? sk->sk_uid : make_kuid(net->user_ns, 0);
2045 }
2046 
2047 static inline u32 net_tx_rndhash(void)
2048 {
2049 	u32 v = get_random_u32();
2050 
2051 	return v ?: 1;
2052 }
2053 
2054 static inline void sk_set_txhash(struct sock *sk)
2055 {
2056 	/* This pairs with READ_ONCE() in skb_set_hash_from_sk() */
2057 	WRITE_ONCE(sk->sk_txhash, net_tx_rndhash());
2058 }
2059 
2060 static inline bool sk_rethink_txhash(struct sock *sk)
2061 {
2062 	if (sk->sk_txhash && sk->sk_txrehash == SOCK_TXREHASH_ENABLED) {
2063 		sk_set_txhash(sk);
2064 		return true;
2065 	}
2066 	return false;
2067 }
2068 
2069 static inline struct dst_entry *
2070 __sk_dst_get(const struct sock *sk)
2071 {
2072 	return rcu_dereference_check(sk->sk_dst_cache,
2073 				     lockdep_sock_is_held(sk));
2074 }
2075 
2076 static inline struct dst_entry *
2077 sk_dst_get(const struct sock *sk)
2078 {
2079 	struct dst_entry *dst;
2080 
2081 	rcu_read_lock();
2082 	dst = rcu_dereference(sk->sk_dst_cache);
2083 	if (dst && !rcuref_get(&dst->__rcuref))
2084 		dst = NULL;
2085 	rcu_read_unlock();
2086 	return dst;
2087 }
2088 
2089 static inline void __dst_negative_advice(struct sock *sk)
2090 {
2091 	struct dst_entry *dst = __sk_dst_get(sk);
2092 
2093 	if (dst && dst->ops->negative_advice)
2094 		dst->ops->negative_advice(sk, dst);
2095 }
2096 
2097 static inline void dst_negative_advice(struct sock *sk)
2098 {
2099 	sk_rethink_txhash(sk);
2100 	__dst_negative_advice(sk);
2101 }
2102 
2103 static inline void
2104 __sk_dst_set(struct sock *sk, struct dst_entry *dst)
2105 {
2106 	struct dst_entry *old_dst;
2107 
2108 	sk_tx_queue_clear(sk);
2109 	WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2110 	old_dst = rcu_dereference_protected(sk->sk_dst_cache,
2111 					    lockdep_sock_is_held(sk));
2112 	rcu_assign_pointer(sk->sk_dst_cache, dst);
2113 	dst_release(old_dst);
2114 }
2115 
2116 static inline void
2117 sk_dst_set(struct sock *sk, struct dst_entry *dst)
2118 {
2119 	struct dst_entry *old_dst;
2120 
2121 	sk_tx_queue_clear(sk);
2122 	WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2123 	old_dst = unrcu_pointer(xchg(&sk->sk_dst_cache, RCU_INITIALIZER(dst)));
2124 	dst_release(old_dst);
2125 }
2126 
2127 static inline void
2128 __sk_dst_reset(struct sock *sk)
2129 {
2130 	__sk_dst_set(sk, NULL);
2131 }
2132 
2133 static inline void
2134 sk_dst_reset(struct sock *sk)
2135 {
2136 	sk_dst_set(sk, NULL);
2137 }
2138 
2139 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
2140 
2141 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
2142 
2143 static inline void sk_dst_confirm(struct sock *sk)
2144 {
2145 	if (!READ_ONCE(sk->sk_dst_pending_confirm))
2146 		WRITE_ONCE(sk->sk_dst_pending_confirm, 1);
2147 }
2148 
2149 static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n)
2150 {
2151 	if (skb_get_dst_pending_confirm(skb)) {
2152 		struct sock *sk = skb->sk;
2153 
2154 		if (sk && READ_ONCE(sk->sk_dst_pending_confirm))
2155 			WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2156 		neigh_confirm(n);
2157 	}
2158 }
2159 
2160 bool sk_mc_loop(const struct sock *sk);
2161 
2162 static inline bool sk_can_gso(const struct sock *sk)
2163 {
2164 	return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
2165 }
2166 
2167 void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
2168 
2169 static inline void sk_gso_disable(struct sock *sk)
2170 {
2171 	sk->sk_gso_disabled = 1;
2172 	sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2173 }
2174 
2175 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
2176 					   struct iov_iter *from, char *to,
2177 					   int copy, int offset)
2178 {
2179 	if (skb->ip_summed == CHECKSUM_NONE) {
2180 		__wsum csum = 0;
2181 		if (!csum_and_copy_from_iter_full(to, copy, &csum, from))
2182 			return -EFAULT;
2183 		skb->csum = csum_block_add(skb->csum, csum, offset);
2184 	} else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
2185 		if (!copy_from_iter_full_nocache(to, copy, from))
2186 			return -EFAULT;
2187 	} else if (!copy_from_iter_full(to, copy, from))
2188 		return -EFAULT;
2189 
2190 	return 0;
2191 }
2192 
2193 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
2194 				       struct iov_iter *from, int copy)
2195 {
2196 	int err, offset = skb->len;
2197 
2198 	err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
2199 				       copy, offset);
2200 	if (err)
2201 		__skb_trim(skb, offset);
2202 
2203 	return err;
2204 }
2205 
2206 static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
2207 					   struct sk_buff *skb,
2208 					   struct page *page,
2209 					   int off, int copy)
2210 {
2211 	int err;
2212 
2213 	err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
2214 				       copy, skb->len);
2215 	if (err)
2216 		return err;
2217 
2218 	skb_len_add(skb, copy);
2219 	sk_wmem_queued_add(sk, copy);
2220 	sk_mem_charge(sk, copy);
2221 	return 0;
2222 }
2223 
2224 /**
2225  * sk_wmem_alloc_get - returns write allocations
2226  * @sk: socket
2227  *
2228  * Return: sk_wmem_alloc minus initial offset of one
2229  */
2230 static inline int sk_wmem_alloc_get(const struct sock *sk)
2231 {
2232 	return refcount_read(&sk->sk_wmem_alloc) - 1;
2233 }
2234 
2235 /**
2236  * sk_rmem_alloc_get - returns read allocations
2237  * @sk: socket
2238  *
2239  * Return: sk_rmem_alloc
2240  */
2241 static inline int sk_rmem_alloc_get(const struct sock *sk)
2242 {
2243 	return atomic_read(&sk->sk_rmem_alloc);
2244 }
2245 
2246 /**
2247  * sk_has_allocations - check if allocations are outstanding
2248  * @sk: socket
2249  *
2250  * Return: true if socket has write or read allocations
2251  */
2252 static inline bool sk_has_allocations(const struct sock *sk)
2253 {
2254 	return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
2255 }
2256 
2257 /**
2258  * skwq_has_sleeper - check if there are any waiting processes
2259  * @wq: struct socket_wq
2260  *
2261  * Return: true if socket_wq has waiting processes
2262  *
2263  * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory
2264  * barrier call. They were added due to the race found within the tcp code.
2265  *
2266  * Consider following tcp code paths::
2267  *
2268  *   CPU1                CPU2
2269  *   sys_select          receive packet
2270  *   ...                 ...
2271  *   __add_wait_queue    update tp->rcv_nxt
2272  *   ...                 ...
2273  *   tp->rcv_nxt check   sock_def_readable
2274  *   ...                 {
2275  *   schedule               rcu_read_lock();
2276  *                          wq = rcu_dereference(sk->sk_wq);
2277  *                          if (wq && waitqueue_active(&wq->wait))
2278  *                              wake_up_interruptible(&wq->wait)
2279  *                          ...
2280  *                       }
2281  *
2282  * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
2283  * in its cache, and so does the tp->rcv_nxt update on CPU2 side.  The CPU1
2284  * could then endup calling schedule and sleep forever if there are no more
2285  * data on the socket.
2286  *
2287  */
2288 static inline bool skwq_has_sleeper(struct socket_wq *wq)
2289 {
2290 	return wq && wq_has_sleeper(&wq->wait);
2291 }
2292 
2293 /**
2294  * sock_poll_wait - place memory barrier behind the poll_wait call.
2295  * @filp:           file
2296  * @sock:           socket to wait on
2297  * @p:              poll_table
2298  *
2299  * See the comments in the wq_has_sleeper function.
2300  */
2301 static inline void sock_poll_wait(struct file *filp, struct socket *sock,
2302 				  poll_table *p)
2303 {
2304 	if (!poll_does_not_wait(p)) {
2305 		poll_wait(filp, &sock->wq.wait, p);
2306 		/* We need to be sure we are in sync with the
2307 		 * socket flags modification.
2308 		 *
2309 		 * This memory barrier is paired in the wq_has_sleeper.
2310 		 */
2311 		smp_mb();
2312 	}
2313 }
2314 
2315 static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk)
2316 {
2317 	/* This pairs with WRITE_ONCE() in sk_set_txhash() */
2318 	u32 txhash = READ_ONCE(sk->sk_txhash);
2319 
2320 	if (txhash) {
2321 		skb->l4_hash = 1;
2322 		skb->hash = txhash;
2323 	}
2324 }
2325 
2326 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);
2327 
2328 /*
2329  *	Queue a received datagram if it will fit. Stream and sequenced
2330  *	protocols can't normally use this as they need to fit buffers in
2331  *	and play with them.
2332  *
2333  *	Inlined as it's very short and called for pretty much every
2334  *	packet ever received.
2335  */
2336 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
2337 {
2338 	skb_orphan(skb);
2339 	skb->sk = sk;
2340 	skb->destructor = sock_rfree;
2341 	atomic_add(skb->truesize, &sk->sk_rmem_alloc);
2342 	sk_mem_charge(sk, skb->truesize);
2343 }
2344 
2345 static inline __must_check bool skb_set_owner_sk_safe(struct sk_buff *skb, struct sock *sk)
2346 {
2347 	if (sk && refcount_inc_not_zero(&sk->sk_refcnt)) {
2348 		skb_orphan(skb);
2349 		skb->destructor = sock_efree;
2350 		skb->sk = sk;
2351 		return true;
2352 	}
2353 	return false;
2354 }
2355 
2356 static inline struct sk_buff *skb_clone_and_charge_r(struct sk_buff *skb, struct sock *sk)
2357 {
2358 	skb = skb_clone(skb, sk_gfp_mask(sk, GFP_ATOMIC));
2359 	if (skb) {
2360 		if (sk_rmem_schedule(sk, skb, skb->truesize)) {
2361 			skb_set_owner_r(skb, sk);
2362 			return skb;
2363 		}
2364 		__kfree_skb(skb);
2365 	}
2366 	return NULL;
2367 }
2368 
2369 static inline void skb_prepare_for_gro(struct sk_buff *skb)
2370 {
2371 	if (skb->destructor != sock_wfree) {
2372 		skb_orphan(skb);
2373 		return;
2374 	}
2375 	skb->slow_gro = 1;
2376 }
2377 
2378 void sk_reset_timer(struct sock *sk, struct timer_list *timer,
2379 		    unsigned long expires);
2380 
2381 void sk_stop_timer(struct sock *sk, struct timer_list *timer);
2382 
2383 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer);
2384 
2385 int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue,
2386 			struct sk_buff *skb, unsigned int flags,
2387 			void (*destructor)(struct sock *sk,
2388 					   struct sk_buff *skb));
2389 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2390 
2391 int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb,
2392 			      enum skb_drop_reason *reason);
2393 
2394 static inline int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
2395 {
2396 	return sock_queue_rcv_skb_reason(sk, skb, NULL);
2397 }
2398 
2399 int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2400 struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
2401 
2402 /*
2403  *	Recover an error report and clear atomically
2404  */
2405 
2406 static inline int sock_error(struct sock *sk)
2407 {
2408 	int err;
2409 
2410 	/* Avoid an atomic operation for the common case.
2411 	 * This is racy since another cpu/thread can change sk_err under us.
2412 	 */
2413 	if (likely(data_race(!sk->sk_err)))
2414 		return 0;
2415 
2416 	err = xchg(&sk->sk_err, 0);
2417 	return -err;
2418 }
2419 
2420 void sk_error_report(struct sock *sk);
2421 
2422 static inline unsigned long sock_wspace(struct sock *sk)
2423 {
2424 	int amt = 0;
2425 
2426 	if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2427 		amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc);
2428 		if (amt < 0)
2429 			amt = 0;
2430 	}
2431 	return amt;
2432 }
2433 
2434 /* Note:
2435  *  We use sk->sk_wq_raw, from contexts knowing this
2436  *  pointer is not NULL and cannot disappear/change.
2437  */
2438 static inline void sk_set_bit(int nr, struct sock *sk)
2439 {
2440 	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2441 	    !sock_flag(sk, SOCK_FASYNC))
2442 		return;
2443 
2444 	set_bit(nr, &sk->sk_wq_raw->flags);
2445 }
2446 
2447 static inline void sk_clear_bit(int nr, struct sock *sk)
2448 {
2449 	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2450 	    !sock_flag(sk, SOCK_FASYNC))
2451 		return;
2452 
2453 	clear_bit(nr, &sk->sk_wq_raw->flags);
2454 }
2455 
2456 static inline void sk_wake_async(const struct sock *sk, int how, int band)
2457 {
2458 	if (sock_flag(sk, SOCK_FASYNC)) {
2459 		rcu_read_lock();
2460 		sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2461 		rcu_read_unlock();
2462 	}
2463 }
2464 
2465 static inline void sk_wake_async_rcu(const struct sock *sk, int how, int band)
2466 {
2467 	if (unlikely(sock_flag(sk, SOCK_FASYNC)))
2468 		sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2469 }
2470 
2471 /* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2472  * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2473  * Note: for send buffers, TCP works better if we can build two skbs at
2474  * minimum.
2475  */
2476 #define TCP_SKB_MIN_TRUESIZE	(2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2477 
2478 #define SOCK_MIN_SNDBUF		(TCP_SKB_MIN_TRUESIZE * 2)
2479 #define SOCK_MIN_RCVBUF		 TCP_SKB_MIN_TRUESIZE
2480 
2481 static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2482 {
2483 	u32 val;
2484 
2485 	if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)
2486 		return;
2487 
2488 	val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2489 	val = max_t(u32, val, sk_unused_reserved_mem(sk));
2490 
2491 	WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF));
2492 }
2493 
2494 /**
2495  * sk_page_frag - return an appropriate page_frag
2496  * @sk: socket
2497  *
2498  * Use the per task page_frag instead of the per socket one for
2499  * optimization when we know that we're in process context and own
2500  * everything that's associated with %current.
2501  *
2502  * Both direct reclaim and page faults can nest inside other
2503  * socket operations and end up recursing into sk_page_frag()
2504  * while it's already in use: explicitly avoid task page_frag
2505  * when users disable sk_use_task_frag.
2506  *
2507  * Return: a per task page_frag if context allows that,
2508  * otherwise a per socket one.
2509  */
2510 static inline struct page_frag *sk_page_frag(struct sock *sk)
2511 {
2512 	if (sk->sk_use_task_frag)
2513 		return &current->task_frag;
2514 
2515 	return &sk->sk_frag;
2516 }
2517 
2518 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2519 
2520 /*
2521  *	Default write policy as shown to user space via poll/select/SIGIO
2522  */
2523 static inline bool sock_writeable(const struct sock *sk)
2524 {
2525 	return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1);
2526 }
2527 
2528 static inline gfp_t gfp_any(void)
2529 {
2530 	return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2531 }
2532 
2533 static inline gfp_t gfp_memcg_charge(void)
2534 {
2535 	return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2536 }
2537 
2538 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2539 {
2540 	return noblock ? 0 : sk->sk_rcvtimeo;
2541 }
2542 
2543 static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2544 {
2545 	return noblock ? 0 : sk->sk_sndtimeo;
2546 }
2547 
2548 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2549 {
2550 	int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len);
2551 
2552 	return v ?: 1;
2553 }
2554 
2555 /* Alas, with timeout socket operations are not restartable.
2556  * Compare this to poll().
2557  */
2558 static inline int sock_intr_errno(long timeo)
2559 {
2560 	return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2561 }
2562 
2563 struct sock_skb_cb {
2564 	u32 dropcount;
2565 };
2566 
2567 /* Store sock_skb_cb at the end of skb->cb[] so protocol families
2568  * using skb->cb[] would keep using it directly and utilize its
2569  * alignment guarantee.
2570  */
2571 #define SOCK_SKB_CB_OFFSET ((sizeof_field(struct sk_buff, cb) - \
2572 			    sizeof(struct sock_skb_cb)))
2573 
2574 #define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
2575 			    SOCK_SKB_CB_OFFSET))
2576 
2577 #define sock_skb_cb_check_size(size) \
2578 	BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
2579 
2580 static inline void
2581 sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
2582 {
2583 	SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ?
2584 						atomic_read(&sk->sk_drops) : 0;
2585 }
2586 
2587 static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb)
2588 {
2589 	int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs);
2590 
2591 	atomic_add(segs, &sk->sk_drops);
2592 }
2593 
2594 static inline ktime_t sock_read_timestamp(struct sock *sk)
2595 {
2596 #if BITS_PER_LONG==32
2597 	unsigned int seq;
2598 	ktime_t kt;
2599 
2600 	do {
2601 		seq = read_seqbegin(&sk->sk_stamp_seq);
2602 		kt = sk->sk_stamp;
2603 	} while (read_seqretry(&sk->sk_stamp_seq, seq));
2604 
2605 	return kt;
2606 #else
2607 	return READ_ONCE(sk->sk_stamp);
2608 #endif
2609 }
2610 
2611 static inline void sock_write_timestamp(struct sock *sk, ktime_t kt)
2612 {
2613 #if BITS_PER_LONG==32
2614 	write_seqlock(&sk->sk_stamp_seq);
2615 	sk->sk_stamp = kt;
2616 	write_sequnlock(&sk->sk_stamp_seq);
2617 #else
2618 	WRITE_ONCE(sk->sk_stamp, kt);
2619 #endif
2620 }
2621 
2622 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2623 			   struct sk_buff *skb);
2624 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2625 			     struct sk_buff *skb);
2626 
2627 static inline void
2628 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2629 {
2630 	struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2631 	u32 tsflags = READ_ONCE(sk->sk_tsflags);
2632 	ktime_t kt = skb->tstamp;
2633 	/*
2634 	 * generate control messages if
2635 	 * - receive time stamping in software requested
2636 	 * - software time stamp available and wanted
2637 	 * - hardware time stamps available and wanted
2638 	 */
2639 	if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2640 	    (tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
2641 	    (kt && tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
2642 	    (hwtstamps->hwtstamp &&
2643 	     (tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
2644 		__sock_recv_timestamp(msg, sk, skb);
2645 	else
2646 		sock_write_timestamp(sk, kt);
2647 
2648 	if (sock_flag(sk, SOCK_WIFI_STATUS) && skb_wifi_acked_valid(skb))
2649 		__sock_recv_wifi_status(msg, sk, skb);
2650 }
2651 
2652 void __sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
2653 		       struct sk_buff *skb);
2654 
2655 #define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC)
2656 static inline void sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
2657 				   struct sk_buff *skb)
2658 {
2659 #define FLAGS_RECV_CMSGS ((1UL << SOCK_RXQ_OVFL)			| \
2660 			   (1UL << SOCK_RCVTSTAMP)			| \
2661 			   (1UL << SOCK_RCVMARK))
2662 #define TSFLAGS_ANY	  (SOF_TIMESTAMPING_SOFTWARE			| \
2663 			   SOF_TIMESTAMPING_RAW_HARDWARE)
2664 
2665 	if (sk->sk_flags & FLAGS_RECV_CMSGS ||
2666 	    READ_ONCE(sk->sk_tsflags) & TSFLAGS_ANY)
2667 		__sock_recv_cmsgs(msg, sk, skb);
2668 	else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP)))
2669 		sock_write_timestamp(sk, skb->tstamp);
2670 	else if (unlikely(sock_read_timestamp(sk) == SK_DEFAULT_STAMP))
2671 		sock_write_timestamp(sk, 0);
2672 }
2673 
2674 void __sock_tx_timestamp(__u32 tsflags, __u8 *tx_flags);
2675 
2676 /**
2677  * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2678  * @sk:		socket sending this packet
2679  * @sockc:	pointer to socket cmsg cookie to get timestamping info
2680  * @tx_flags:	completed with instructions for time stamping
2681  * @tskey:      filled in with next sk_tskey (not for TCP, which uses seqno)
2682  *
2683  * Note: callers should take care of initial ``*tx_flags`` value (usually 0)
2684  */
2685 static inline void _sock_tx_timestamp(struct sock *sk,
2686 				      const struct sockcm_cookie *sockc,
2687 				      __u8 *tx_flags, __u32 *tskey)
2688 {
2689 	__u32 tsflags = sockc->tsflags;
2690 
2691 	if (unlikely(tsflags)) {
2692 		__sock_tx_timestamp(tsflags, tx_flags);
2693 		if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey &&
2694 		    tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK) {
2695 			if (tsflags & SOCKCM_FLAG_TS_OPT_ID)
2696 				*tskey = sockc->ts_opt_id;
2697 			else
2698 				*tskey = atomic_inc_return(&sk->sk_tskey) - 1;
2699 		}
2700 	}
2701 	if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
2702 		*tx_flags |= SKBTX_WIFI_STATUS;
2703 }
2704 
2705 static inline void sock_tx_timestamp(struct sock *sk,
2706 				     const struct sockcm_cookie *sockc,
2707 				     __u8 *tx_flags)
2708 {
2709 	_sock_tx_timestamp(sk, sockc, tx_flags, NULL);
2710 }
2711 
2712 static inline void skb_setup_tx_timestamp(struct sk_buff *skb,
2713 					  const struct sockcm_cookie *sockc)
2714 {
2715 	_sock_tx_timestamp(skb->sk, sockc, &skb_shinfo(skb)->tx_flags,
2716 			   &skb_shinfo(skb)->tskey);
2717 }
2718 
2719 static inline bool sk_is_inet(const struct sock *sk)
2720 {
2721 	int family = READ_ONCE(sk->sk_family);
2722 
2723 	return family == AF_INET || family == AF_INET6;
2724 }
2725 
2726 static inline bool sk_is_tcp(const struct sock *sk)
2727 {
2728 	return sk_is_inet(sk) &&
2729 	       sk->sk_type == SOCK_STREAM &&
2730 	       sk->sk_protocol == IPPROTO_TCP;
2731 }
2732 
2733 static inline bool sk_is_udp(const struct sock *sk)
2734 {
2735 	return sk_is_inet(sk) &&
2736 	       sk->sk_type == SOCK_DGRAM &&
2737 	       sk->sk_protocol == IPPROTO_UDP;
2738 }
2739 
2740 static inline bool sk_is_stream_unix(const struct sock *sk)
2741 {
2742 	return sk->sk_family == AF_UNIX && sk->sk_type == SOCK_STREAM;
2743 }
2744 
2745 /**
2746  * sk_eat_skb - Release a skb if it is no longer needed
2747  * @sk: socket to eat this skb from
2748  * @skb: socket buffer to eat
2749  *
2750  * This routine must be called with interrupts disabled or with the socket
2751  * locked so that the sk_buff queue operation is ok.
2752 */
2753 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
2754 {
2755 	__skb_unlink(skb, &sk->sk_receive_queue);
2756 	__kfree_skb(skb);
2757 }
2758 
2759 static inline bool
2760 skb_sk_is_prefetched(struct sk_buff *skb)
2761 {
2762 #ifdef CONFIG_INET
2763 	return skb->destructor == sock_pfree;
2764 #else
2765 	return false;
2766 #endif /* CONFIG_INET */
2767 }
2768 
2769 /* This helper checks if a socket is a full socket,
2770  * ie _not_ a timewait or request socket.
2771  */
2772 static inline bool sk_fullsock(const struct sock *sk)
2773 {
2774 	return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
2775 }
2776 
2777 static inline bool
2778 sk_is_refcounted(struct sock *sk)
2779 {
2780 	/* Only full sockets have sk->sk_flags. */
2781 	return !sk_fullsock(sk) || !sock_flag(sk, SOCK_RCU_FREE);
2782 }
2783 
2784 /* Checks if this SKB belongs to an HW offloaded socket
2785  * and whether any SW fallbacks are required based on dev.
2786  * Check decrypted mark in case skb_orphan() cleared socket.
2787  */
2788 static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb,
2789 						   struct net_device *dev)
2790 {
2791 #ifdef CONFIG_SOCK_VALIDATE_XMIT
2792 	struct sock *sk = skb->sk;
2793 
2794 	if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) {
2795 		skb = sk->sk_validate_xmit_skb(sk, dev, skb);
2796 	} else if (unlikely(skb_is_decrypted(skb))) {
2797 		pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n");
2798 		kfree_skb(skb);
2799 		skb = NULL;
2800 	}
2801 #endif
2802 
2803 	return skb;
2804 }
2805 
2806 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
2807  * SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
2808  */
2809 static inline bool sk_listener(const struct sock *sk)
2810 {
2811 	return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
2812 }
2813 
2814 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV or TIME_WAIT
2815  * TCP SYNACK messages can be attached to LISTEN or NEW_SYN_RECV (depending on SYNCOOKIE)
2816  * TCP RST and ACK can be attached to TIME_WAIT.
2817  */
2818 static inline bool sk_listener_or_tw(const struct sock *sk)
2819 {
2820 	return (1 << READ_ONCE(sk->sk_state)) &
2821 	       (TCPF_LISTEN | TCPF_NEW_SYN_RECV | TCPF_TIME_WAIT);
2822 }
2823 
2824 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag);
2825 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
2826 		       int type);
2827 
2828 bool sk_ns_capable(const struct sock *sk,
2829 		   struct user_namespace *user_ns, int cap);
2830 bool sk_capable(const struct sock *sk, int cap);
2831 bool sk_net_capable(const struct sock *sk, int cap);
2832 
2833 void sk_get_meminfo(const struct sock *sk, u32 *meminfo);
2834 
2835 /* Take into consideration the size of the struct sk_buff overhead in the
2836  * determination of these values, since that is non-constant across
2837  * platforms.  This makes socket queueing behavior and performance
2838  * not depend upon such differences.
2839  */
2840 #define _SK_MEM_PACKETS		256
2841 #define _SK_MEM_OVERHEAD	SKB_TRUESIZE(256)
2842 #define SK_WMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2843 #define SK_RMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2844 
2845 extern __u32 sysctl_wmem_max;
2846 extern __u32 sysctl_rmem_max;
2847 
2848 extern __u32 sysctl_wmem_default;
2849 extern __u32 sysctl_rmem_default;
2850 
2851 #define SKB_FRAG_PAGE_ORDER	get_order(32768)
2852 DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2853 
2854 static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto)
2855 {
2856 	/* Does this proto have per netns sysctl_wmem ? */
2857 	if (proto->sysctl_wmem_offset)
2858 		return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset));
2859 
2860 	return READ_ONCE(*proto->sysctl_wmem);
2861 }
2862 
2863 static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto)
2864 {
2865 	/* Does this proto have per netns sysctl_rmem ? */
2866 	if (proto->sysctl_rmem_offset)
2867 		return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset));
2868 
2869 	return READ_ONCE(*proto->sysctl_rmem);
2870 }
2871 
2872 /* Default TCP Small queue budget is ~1 ms of data (1sec >> 10)
2873  * Some wifi drivers need to tweak it to get more chunks.
2874  * They can use this helper from their ndo_start_xmit()
2875  */
2876 static inline void sk_pacing_shift_update(struct sock *sk, int val)
2877 {
2878 	if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val)
2879 		return;
2880 	WRITE_ONCE(sk->sk_pacing_shift, val);
2881 }
2882 
2883 /* if a socket is bound to a device, check that the given device
2884  * index is either the same or that the socket is bound to an L3
2885  * master device and the given device index is also enslaved to
2886  * that L3 master
2887  */
2888 static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif)
2889 {
2890 	int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
2891 	int mdif;
2892 
2893 	if (!bound_dev_if || bound_dev_if == dif)
2894 		return true;
2895 
2896 	mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif);
2897 	if (mdif && mdif == bound_dev_if)
2898 		return true;
2899 
2900 	return false;
2901 }
2902 
2903 void sock_def_readable(struct sock *sk);
2904 
2905 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk);
2906 void sock_set_timestamp(struct sock *sk, int optname, bool valbool);
2907 int sock_set_timestamping(struct sock *sk, int optname,
2908 			  struct so_timestamping timestamping);
2909 
2910 void sock_enable_timestamps(struct sock *sk);
2911 void sock_no_linger(struct sock *sk);
2912 void sock_set_keepalive(struct sock *sk);
2913 void sock_set_priority(struct sock *sk, u32 priority);
2914 void sock_set_rcvbuf(struct sock *sk, int val);
2915 void sock_set_mark(struct sock *sk, u32 val);
2916 void sock_set_reuseaddr(struct sock *sk);
2917 void sock_set_reuseport(struct sock *sk);
2918 void sock_set_sndtimeo(struct sock *sk, s64 secs);
2919 
2920 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len);
2921 
2922 int sock_get_timeout(long timeo, void *optval, bool old_timeval);
2923 int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
2924 			   sockptr_t optval, int optlen, bool old_timeval);
2925 
2926 int sock_ioctl_inout(struct sock *sk, unsigned int cmd,
2927 		     void __user *arg, void *karg, size_t size);
2928 int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg);
2929 static inline bool sk_is_readable(struct sock *sk)
2930 {
2931 	if (sk->sk_prot->sock_is_readable)
2932 		return sk->sk_prot->sock_is_readable(sk);
2933 	return false;
2934 }
2935 #endif	/* _SOCK_H */
2936