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/* Define this to get the SOCK_DBG debugging facility. */
80#define SOCK_DEBUGGING
81#ifdef SOCK_DEBUGGING
82#define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
83 printk(KERN_DEBUG msg); } while (0)
84#else
85/* Validate arguments and do nothing */
86static inline __printf(2, 3)
87void SOCK_DEBUG(const struct sock *sk, const char *msg, ...)
88{
89}
90#endif
91
92/* This is the per-socket lock. The spinlock provides a synchronization
93 * between user contexts and software interrupt processing, whereas the
94 * mini-semaphore synchronizes multiple users amongst themselves.
95 */
96typedef struct {
97 spinlock_t slock;
98 int owned;
99 wait_queue_head_t wq;
100 /*
101 * We express the mutex-alike socket_lock semantics
102 * to the lock validator by explicitly managing
103 * the slock as a lock variant (in addition to
104 * the slock itself):
105 */
106#ifdef CONFIG_DEBUG_LOCK_ALLOC
107 struct lockdep_map dep_map;
108#endif
109} socket_lock_t;
110
111struct sock;
112struct proto;
113struct net;
114
115typedef __u32 __bitwise __portpair;
116typedef __u64 __bitwise __addrpair;
117
118/**
119 * struct sock_common - minimal network layer representation of sockets
120 * @skc_daddr: Foreign IPv4 addr
121 * @skc_rcv_saddr: Bound local IPv4 addr
122 * @skc_addrpair: 8-byte-aligned __u64 union of @skc_daddr & @skc_rcv_saddr
123 * @skc_hash: hash value used with various protocol lookup tables
124 * @skc_u16hashes: two u16 hash values used by UDP lookup tables
125 * @skc_dport: placeholder for inet_dport/tw_dport
126 * @skc_num: placeholder for inet_num/tw_num
127 * @skc_portpair: __u32 union of @skc_dport & @skc_num
128 * @skc_family: network address family
129 * @skc_state: Connection state
130 * @skc_reuse: %SO_REUSEADDR setting
131 * @skc_reuseport: %SO_REUSEPORT setting
132 * @skc_ipv6only: socket is IPV6 only
133 * @skc_net_refcnt: socket is using net ref counting
134 * @skc_bound_dev_if: bound device index if != 0
135 * @skc_bind_node: bind hash linkage for various protocol lookup tables
136 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
137 * @skc_prot: protocol handlers inside a network family
138 * @skc_net: reference to the network namespace of this socket
139 * @skc_v6_daddr: IPV6 destination address
140 * @skc_v6_rcv_saddr: IPV6 source address
141 * @skc_cookie: socket's cookie value
142 * @skc_node: main hash linkage for various protocol lookup tables
143 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
144 * @skc_tx_queue_mapping: tx queue number for this connection
145 * @skc_rx_queue_mapping: rx queue number for this connection
146 * @skc_flags: place holder for sk_flags
147 * %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
148 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings
149 * @skc_listener: connection request listener socket (aka rsk_listener)
150 * [union with @skc_flags]
151 * @skc_tw_dr: (aka tw_dr) ptr to &struct inet_timewait_death_row
152 * [union with @skc_flags]
153 * @skc_incoming_cpu: record/match cpu processing incoming packets
154 * @skc_rcv_wnd: (aka rsk_rcv_wnd) TCP receive window size (possibly scaled)
155 * [union with @skc_incoming_cpu]
156 * @skc_tw_rcv_nxt: (aka tw_rcv_nxt) TCP window next expected seq number
157 * [union with @skc_incoming_cpu]
158 * @skc_refcnt: reference count
159 *
160 * This is the minimal network layer representation of sockets, the header
161 * for struct sock and struct inet_timewait_sock.
162 */
163struct sock_common {
164 union {
165 __addrpair skc_addrpair;
166 struct {
167 __be32 skc_daddr;
168 __be32 skc_rcv_saddr;
169 };
170 };
171 union {
172 unsigned int skc_hash;
173 __u16 skc_u16hashes[2];
174 };
175 /* skc_dport && skc_num must be grouped as well */
176 union {
177 __portpair skc_portpair;
178 struct {
179 __be16 skc_dport;
180 __u16 skc_num;
181 };
182 };
183
184 unsigned short skc_family;
185 volatile unsigned char skc_state;
186 unsigned char skc_reuse:4;
187 unsigned char skc_reuseport:1;
188 unsigned char skc_ipv6only:1;
189 unsigned char skc_net_refcnt:1;
190 int skc_bound_dev_if;
191 union {
192 struct hlist_node skc_bind_node;
193 struct hlist_node skc_portaddr_node;
194 };
195 struct proto *skc_prot;
196 possible_net_t skc_net;
197
198#if IS_ENABLED(CONFIG_IPV6)
199 struct in6_addr skc_v6_daddr;
200 struct in6_addr skc_v6_rcv_saddr;
201#endif
202
203 atomic64_t skc_cookie;
204
205 /* following fields are padding to force
206 * offset(struct sock, sk_refcnt) == 128 on 64bit arches
207 * assuming IPV6 is enabled. We use this padding differently
208 * for different kind of 'sockets'
209 */
210 union {
211 unsigned long skc_flags;
212 struct sock *skc_listener; /* request_sock */
213 struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */
214 };
215 /*
216 * fields between dontcopy_begin/dontcopy_end
217 * are not copied in sock_copy()
218 */
219 /* private: */
220 int skc_dontcopy_begin[0];
221 /* public: */
222 union {
223 struct hlist_node skc_node;
224 struct hlist_nulls_node skc_nulls_node;
225 };
226 unsigned short skc_tx_queue_mapping;
227#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
228 unsigned short skc_rx_queue_mapping;
229#endif
230 union {
231 int skc_incoming_cpu;
232 u32 skc_rcv_wnd;
233 u32 skc_tw_rcv_nxt; /* struct tcp_timewait_sock */
234 };
235
236 refcount_t skc_refcnt;
237 /* private: */
238 int skc_dontcopy_end[0];
239 union {
240 u32 skc_rxhash;
241 u32 skc_window_clamp;
242 u32 skc_tw_snd_nxt; /* struct tcp_timewait_sock */
243 };
244 /* public: */
245};
246
247struct bpf_local_storage;
248struct sk_filter;
249
250/**
251 * struct sock - network layer representation of sockets
252 * @__sk_common: shared layout with inet_timewait_sock
253 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
254 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
255 * @sk_lock: synchronizer
256 * @sk_kern_sock: True if sock is using kernel lock classes
257 * @sk_rcvbuf: size of receive buffer in bytes
258 * @sk_wq: sock wait queue and async head
259 * @sk_rx_dst: receive input route used by early demux
260 * @sk_rx_dst_ifindex: ifindex for @sk_rx_dst
261 * @sk_rx_dst_cookie: cookie for @sk_rx_dst
262 * @sk_dst_cache: destination cache
263 * @sk_dst_pending_confirm: need to confirm neighbour
264 * @sk_policy: flow policy
265 * @sk_receive_queue: incoming packets
266 * @sk_wmem_alloc: transmit queue bytes committed
267 * @sk_tsq_flags: TCP Small Queues flags
268 * @sk_write_queue: Packet sending queue
269 * @sk_omem_alloc: "o" is "option" or "other"
270 * @sk_wmem_queued: persistent queue size
271 * @sk_forward_alloc: space allocated forward
272 * @sk_reserved_mem: space reserved and non-reclaimable for the socket
273 * @sk_napi_id: id of the last napi context to receive data for sk
274 * @sk_ll_usec: usecs to busypoll when there is no data
275 * @sk_allocation: allocation mode
276 * @sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler)
277 * @sk_pacing_status: Pacing status (requested, handled by sch_fq)
278 * @sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE)
279 * @sk_sndbuf: size of send buffer in bytes
280 * @__sk_flags_offset: empty field used to determine location of bitfield
281 * @sk_padding: unused element for alignment
282 * @sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets
283 * @sk_no_check_rx: allow zero checksum in RX packets
284 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
285 * @sk_gso_disabled: if set, NETIF_F_GSO_MASK is forbidden.
286 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
287 * @sk_gso_max_size: Maximum GSO segment size to build
288 * @sk_gso_max_segs: Maximum number of GSO segments
289 * @sk_pacing_shift: scaling factor for TCP Small Queues
290 * @sk_lingertime: %SO_LINGER l_linger setting
291 * @sk_backlog: always used with the per-socket spinlock held
292 * @sk_callback_lock: used with the callbacks in the end of this struct
293 * @sk_error_queue: rarely used
294 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
295 * IPV6_ADDRFORM for instance)
296 * @sk_err: last error
297 * @sk_err_soft: errors that don't cause failure but are the cause of a
298 * persistent failure not just 'timed out'
299 * @sk_drops: raw/udp drops counter
300 * @sk_ack_backlog: current listen backlog
301 * @sk_max_ack_backlog: listen backlog set in listen()
302 * @sk_uid: user id of owner
303 * @sk_prefer_busy_poll: prefer busypolling over softirq processing
304 * @sk_busy_poll_budget: napi processing budget when busypolling
305 * @sk_priority: %SO_PRIORITY setting
306 * @sk_type: socket type (%SOCK_STREAM, etc)
307 * @sk_protocol: which protocol this socket belongs in this network family
308 * @sk_peer_lock: lock protecting @sk_peer_pid and @sk_peer_cred
309 * @sk_peer_pid: &struct pid for this socket's peer
310 * @sk_peer_cred: %SO_PEERCRED setting
311 * @sk_rcvlowat: %SO_RCVLOWAT setting
312 * @sk_rcvtimeo: %SO_RCVTIMEO setting
313 * @sk_sndtimeo: %SO_SNDTIMEO setting
314 * @sk_txhash: computed flow hash for use on transmit
315 * @sk_txrehash: enable TX hash rethink
316 * @sk_filter: socket filtering instructions
317 * @sk_timer: sock cleanup timer
318 * @sk_stamp: time stamp of last packet received
319 * @sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only
320 * @sk_tsflags: SO_TIMESTAMPING flags
321 * @sk_bind_phc: SO_TIMESTAMPING bind PHC index of PTP virtual clock
322 * for timestamping
323 * @sk_tskey: counter to disambiguate concurrent tstamp requests
324 * @sk_zckey: counter to order MSG_ZEROCOPY notifications
325 * @sk_socket: Identd and reporting IO signals
326 * @sk_user_data: RPC layer private data
327 * @sk_frag: cached page frag
328 * @sk_peek_off: current peek_offset value
329 * @sk_send_head: front of stuff to transmit
330 * @tcp_rtx_queue: TCP re-transmit queue [union with @sk_send_head]
331 * @sk_security: used by security modules
332 * @sk_mark: generic packet mark
333 * @sk_cgrp_data: cgroup data for this cgroup
334 * @sk_memcg: this socket's memory cgroup association
335 * @sk_write_pending: a write to stream socket waits to start
336 * @sk_state_change: callback to indicate change in the state of the sock
337 * @sk_data_ready: callback to indicate there is data to be processed
338 * @sk_write_space: callback to indicate there is bf sending space available
339 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
340 * @sk_backlog_rcv: callback to process the backlog
341 * @sk_validate_xmit_skb: ptr to an optional validate function
342 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
343 * @sk_reuseport_cb: reuseport group container
344 * @sk_bpf_storage: ptr to cache and control for bpf_sk_storage
345 * @sk_rcu: used during RCU grace period
346 * @sk_clockid: clockid used by time-based scheduling (SO_TXTIME)
347 * @sk_txtime_deadline_mode: set deadline mode for SO_TXTIME
348 * @sk_txtime_report_errors: set report errors mode for SO_TXTIME
349 * @sk_txtime_unused: unused txtime flags
350 * @ns_tracker: tracker for netns reference
351 */
352struct sock {
353 /*
354 * Now struct inet_timewait_sock also uses sock_common, so please just
355 * don't add nothing before this first member (__sk_common) --acme
356 */
357 struct sock_common __sk_common;
358#define sk_node __sk_common.skc_node
359#define sk_nulls_node __sk_common.skc_nulls_node
360#define sk_refcnt __sk_common.skc_refcnt
361#define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping
362#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
363#define sk_rx_queue_mapping __sk_common.skc_rx_queue_mapping
364#endif
365
366#define sk_dontcopy_begin __sk_common.skc_dontcopy_begin
367#define sk_dontcopy_end __sk_common.skc_dontcopy_end
368#define sk_hash __sk_common.skc_hash
369#define sk_portpair __sk_common.skc_portpair
370#define sk_num __sk_common.skc_num
371#define sk_dport __sk_common.skc_dport
372#define sk_addrpair __sk_common.skc_addrpair
373#define sk_daddr __sk_common.skc_daddr
374#define sk_rcv_saddr __sk_common.skc_rcv_saddr
375#define sk_family __sk_common.skc_family
376#define sk_state __sk_common.skc_state
377#define sk_reuse __sk_common.skc_reuse
378#define sk_reuseport __sk_common.skc_reuseport
379#define sk_ipv6only __sk_common.skc_ipv6only
380#define sk_net_refcnt __sk_common.skc_net_refcnt
381#define sk_bound_dev_if __sk_common.skc_bound_dev_if
382#define sk_bind_node __sk_common.skc_bind_node
383#define sk_prot __sk_common.skc_prot
384#define sk_net __sk_common.skc_net
385#define sk_v6_daddr __sk_common.skc_v6_daddr
386#define sk_v6_rcv_saddr __sk_common.skc_v6_rcv_saddr
387#define sk_cookie __sk_common.skc_cookie
388#define sk_incoming_cpu __sk_common.skc_incoming_cpu
389#define sk_flags __sk_common.skc_flags
390#define sk_rxhash __sk_common.skc_rxhash
391
392 /* early demux fields */
393 struct dst_entry __rcu *sk_rx_dst;
394 int sk_rx_dst_ifindex;
395 u32 sk_rx_dst_cookie;
396
397 socket_lock_t sk_lock;
398 atomic_t sk_drops;
399 int sk_rcvlowat;
400 struct sk_buff_head sk_error_queue;
401 struct sk_buff_head sk_receive_queue;
402 /*
403 * The backlog queue is special, it is always used with
404 * the per-socket spinlock held and requires low latency
405 * access. Therefore we special case it's implementation.
406 * Note : rmem_alloc is in this structure to fill a hole
407 * on 64bit arches, not because its logically part of
408 * backlog.
409 */
410 struct {
411 atomic_t rmem_alloc;
412 int len;
413 struct sk_buff *head;
414 struct sk_buff *tail;
415 } sk_backlog;
416
417#define sk_rmem_alloc sk_backlog.rmem_alloc
418
419 int sk_forward_alloc;
420 u32 sk_reserved_mem;
421#ifdef CONFIG_NET_RX_BUSY_POLL
422 unsigned int sk_ll_usec;
423 /* ===== mostly read cache line ===== */
424 unsigned int sk_napi_id;
425#endif
426 int sk_rcvbuf;
427
428 struct sk_filter __rcu *sk_filter;
429 union {
430 struct socket_wq __rcu *sk_wq;
431 /* private: */
432 struct socket_wq *sk_wq_raw;
433 /* public: */
434 };
435#ifdef CONFIG_XFRM
436 struct xfrm_policy __rcu *sk_policy[2];
437#endif
438
439 struct dst_entry __rcu *sk_dst_cache;
440 atomic_t sk_omem_alloc;
441 int sk_sndbuf;
442
443 /* ===== cache line for TX ===== */
444 int sk_wmem_queued;
445 refcount_t sk_wmem_alloc;
446 unsigned long sk_tsq_flags;
447 union {
448 struct sk_buff *sk_send_head;
449 struct rb_root tcp_rtx_queue;
450 };
451 struct sk_buff_head sk_write_queue;
452 __s32 sk_peek_off;
453 int sk_write_pending;
454 __u32 sk_dst_pending_confirm;
455 u32 sk_pacing_status; /* see enum sk_pacing */
456 long sk_sndtimeo;
457 struct timer_list sk_timer;
458 __u32 sk_priority;
459 __u32 sk_mark;
460 unsigned long sk_pacing_rate; /* bytes per second */
461 unsigned long sk_max_pacing_rate;
462 struct page_frag sk_frag;
463 netdev_features_t sk_route_caps;
464 int sk_gso_type;
465 unsigned int sk_gso_max_size;
466 gfp_t sk_allocation;
467 __u32 sk_txhash;
468
469 /*
470 * Because of non atomicity rules, all
471 * changes are protected by socket lock.
472 */
473 u8 sk_gso_disabled : 1,
474 sk_kern_sock : 1,
475 sk_no_check_tx : 1,
476 sk_no_check_rx : 1,
477 sk_userlocks : 4;
478 u8 sk_pacing_shift;
479 u16 sk_type;
480 u16 sk_protocol;
481 u16 sk_gso_max_segs;
482 unsigned long sk_lingertime;
483 struct proto *sk_prot_creator;
484 rwlock_t sk_callback_lock;
485 int sk_err,
486 sk_err_soft;
487 u32 sk_ack_backlog;
488 u32 sk_max_ack_backlog;
489 kuid_t sk_uid;
490 u8 sk_txrehash;
491#ifdef CONFIG_NET_RX_BUSY_POLL
492 u8 sk_prefer_busy_poll;
493 u16 sk_busy_poll_budget;
494#endif
495 spinlock_t sk_peer_lock;
496 int sk_bind_phc;
497 struct pid *sk_peer_pid;
498 const struct cred *sk_peer_cred;
499
500 long sk_rcvtimeo;
501 ktime_t sk_stamp;
502#if BITS_PER_LONG==32
503 seqlock_t sk_stamp_seq;
504#endif
505 u16 sk_tsflags;
506 u8 sk_shutdown;
507 atomic_t sk_tskey;
508 atomic_t sk_zckey;
509
510 u8 sk_clockid;
511 u8 sk_txtime_deadline_mode : 1,
512 sk_txtime_report_errors : 1,
513 sk_txtime_unused : 6;
514
515 struct socket *sk_socket;
516 void *sk_user_data;
517#ifdef CONFIG_SECURITY
518 void *sk_security;
519#endif
520 struct sock_cgroup_data sk_cgrp_data;
521 struct mem_cgroup *sk_memcg;
522 void (*sk_state_change)(struct sock *sk);
523 void (*sk_data_ready)(struct sock *sk);
524 void (*sk_write_space)(struct sock *sk);
525 void (*sk_error_report)(struct sock *sk);
526 int (*sk_backlog_rcv)(struct sock *sk,
527 struct sk_buff *skb);
528#ifdef CONFIG_SOCK_VALIDATE_XMIT
529 struct sk_buff* (*sk_validate_xmit_skb)(struct sock *sk,
530 struct net_device *dev,
531 struct sk_buff *skb);
532#endif
533 void (*sk_destruct)(struct sock *sk);
534 struct sock_reuseport __rcu *sk_reuseport_cb;
535#ifdef CONFIG_BPF_SYSCALL
536 struct bpf_local_storage __rcu *sk_bpf_storage;
537#endif
538 struct rcu_head sk_rcu;
539 netns_tracker ns_tracker;
540};
541
542enum sk_pacing {
543 SK_PACING_NONE = 0,
544 SK_PACING_NEEDED = 1,
545 SK_PACING_FQ = 2,
546};
547
548/* flag bits in sk_user_data
549 *
550 * - SK_USER_DATA_NOCOPY: Pointer stored in sk_user_data might
551 * not be suitable for copying when cloning the socket. For instance,
552 * it can point to a reference counted object. sk_user_data bottom
553 * bit is set if pointer must not be copied.
554 *
555 * - SK_USER_DATA_BPF: Mark whether sk_user_data field is
556 * managed/owned by a BPF reuseport array. This bit should be set
557 * when sk_user_data's sk is added to the bpf's reuseport_array.
558 *
559 * - SK_USER_DATA_PSOCK: Mark whether pointer stored in
560 * sk_user_data points to psock type. This bit should be set
561 * when sk_user_data is assigned to a psock object.
562 */
563#define SK_USER_DATA_NOCOPY 1UL
564#define SK_USER_DATA_BPF 2UL
565#define SK_USER_DATA_PSOCK 4UL
566#define SK_USER_DATA_PTRMASK ~(SK_USER_DATA_NOCOPY | SK_USER_DATA_BPF |\
567 SK_USER_DATA_PSOCK)
568
569/**
570 * sk_user_data_is_nocopy - Test if sk_user_data pointer must not be copied
571 * @sk: socket
572 */
573static inline bool sk_user_data_is_nocopy(const struct sock *sk)
574{
575 return ((uintptr_t)sk->sk_user_data & SK_USER_DATA_NOCOPY);
576}
577
578#define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
579
580/**
581 * __rcu_dereference_sk_user_data_with_flags - return the pointer
582 * only if argument flags all has been set in sk_user_data. Otherwise
583 * return NULL
584 *
585 * @sk: socket
586 * @flags: flag bits
587 */
588static inline void *
589__rcu_dereference_sk_user_data_with_flags(const struct sock *sk,
590 uintptr_t flags)
591{
592 uintptr_t sk_user_data = (uintptr_t)rcu_dereference(__sk_user_data(sk));
593
594 WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK);
595
596 if ((sk_user_data & flags) == flags)
597 return (void *)(sk_user_data & SK_USER_DATA_PTRMASK);
598 return NULL;
599}
600
601#define rcu_dereference_sk_user_data(sk) \
602 __rcu_dereference_sk_user_data_with_flags(sk, 0)
603#define __rcu_assign_sk_user_data_with_flags(sk, ptr, flags) \
604({ \
605 uintptr_t __tmp1 = (uintptr_t)(ptr), \
606 __tmp2 = (uintptr_t)(flags); \
607 WARN_ON_ONCE(__tmp1 & ~SK_USER_DATA_PTRMASK); \
608 WARN_ON_ONCE(__tmp2 & SK_USER_DATA_PTRMASK); \
609 rcu_assign_pointer(__sk_user_data((sk)), \
610 __tmp1 | __tmp2); \
611})
612#define rcu_assign_sk_user_data(sk, ptr) \
613 __rcu_assign_sk_user_data_with_flags(sk, ptr, 0)
614
615static inline
616struct net *sock_net(const struct sock *sk)
617{
618 return read_pnet(&sk->sk_net);
619}
620
621static inline
622void sock_net_set(struct sock *sk, struct net *net)
623{
624 write_pnet(&sk->sk_net, net);
625}
626
627/*
628 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
629 * or not whether his port will be reused by someone else. SK_FORCE_REUSE
630 * on a socket means that the socket will reuse everybody else's port
631 * without looking at the other's sk_reuse value.
632 */
633
634#define SK_NO_REUSE 0
635#define SK_CAN_REUSE 1
636#define SK_FORCE_REUSE 2
637
638int sk_set_peek_off(struct sock *sk, int val);
639
640static inline int sk_peek_offset(const struct sock *sk, int flags)
641{
642 if (unlikely(flags & MSG_PEEK)) {
643 return READ_ONCE(sk->sk_peek_off);
644 }
645
646 return 0;
647}
648
649static inline void sk_peek_offset_bwd(struct sock *sk, int val)
650{
651 s32 off = READ_ONCE(sk->sk_peek_off);
652
653 if (unlikely(off >= 0)) {
654 off = max_t(s32, off - val, 0);
655 WRITE_ONCE(sk->sk_peek_off, off);
656 }
657}
658
659static inline void sk_peek_offset_fwd(struct sock *sk, int val)
660{
661 sk_peek_offset_bwd(sk, -val);
662}
663
664/*
665 * Hashed lists helper routines
666 */
667static inline struct sock *sk_entry(const struct hlist_node *node)
668{
669 return hlist_entry(node, struct sock, sk_node);
670}
671
672static inline struct sock *__sk_head(const struct hlist_head *head)
673{
674 return hlist_entry(head->first, struct sock, sk_node);
675}
676
677static inline struct sock *sk_head(const struct hlist_head *head)
678{
679 return hlist_empty(head) ? NULL : __sk_head(head);
680}
681
682static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
683{
684 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
685}
686
687static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
688{
689 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
690}
691
692static inline struct sock *sk_next(const struct sock *sk)
693{
694 return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node);
695}
696
697static inline struct sock *sk_nulls_next(const struct sock *sk)
698{
699 return (!is_a_nulls(sk->sk_nulls_node.next)) ?
700 hlist_nulls_entry(sk->sk_nulls_node.next,
701 struct sock, sk_nulls_node) :
702 NULL;
703}
704
705static inline bool sk_unhashed(const struct sock *sk)
706{
707 return hlist_unhashed(&sk->sk_node);
708}
709
710static inline bool sk_hashed(const struct sock *sk)
711{
712 return !sk_unhashed(sk);
713}
714
715static inline void sk_node_init(struct hlist_node *node)
716{
717 node->pprev = NULL;
718}
719
720static inline void sk_nulls_node_init(struct hlist_nulls_node *node)
721{
722 node->pprev = NULL;
723}
724
725static inline void __sk_del_node(struct sock *sk)
726{
727 __hlist_del(&sk->sk_node);
728}
729
730/* NB: equivalent to hlist_del_init_rcu */
731static inline bool __sk_del_node_init(struct sock *sk)
732{
733 if (sk_hashed(sk)) {
734 __sk_del_node(sk);
735 sk_node_init(&sk->sk_node);
736 return true;
737 }
738 return false;
739}
740
741/* Grab socket reference count. This operation is valid only
742 when sk is ALREADY grabbed f.e. it is found in hash table
743 or a list and the lookup is made under lock preventing hash table
744 modifications.
745 */
746
747static __always_inline void sock_hold(struct sock *sk)
748{
749 refcount_inc(&sk->sk_refcnt);
750}
751
752/* Ungrab socket in the context, which assumes that socket refcnt
753 cannot hit zero, f.e. it is true in context of any socketcall.
754 */
755static __always_inline void __sock_put(struct sock *sk)
756{
757 refcount_dec(&sk->sk_refcnt);
758}
759
760static inline bool sk_del_node_init(struct sock *sk)
761{
762 bool rc = __sk_del_node_init(sk);
763
764 if (rc) {
765 /* paranoid for a while -acme */
766 WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
767 __sock_put(sk);
768 }
769 return rc;
770}
771#define sk_del_node_init_rcu(sk) sk_del_node_init(sk)
772
773static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
774{
775 if (sk_hashed(sk)) {
776 hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
777 return true;
778 }
779 return false;
780}
781
782static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
783{
784 bool rc = __sk_nulls_del_node_init_rcu(sk);
785
786 if (rc) {
787 /* paranoid for a while -acme */
788 WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
789 __sock_put(sk);
790 }
791 return rc;
792}
793
794static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
795{
796 hlist_add_head(&sk->sk_node, list);
797}
798
799static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
800{
801 sock_hold(sk);
802 __sk_add_node(sk, list);
803}
804
805static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
806{
807 sock_hold(sk);
808 if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
809 sk->sk_family == AF_INET6)
810 hlist_add_tail_rcu(&sk->sk_node, list);
811 else
812 hlist_add_head_rcu(&sk->sk_node, list);
813}
814
815static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list)
816{
817 sock_hold(sk);
818 hlist_add_tail_rcu(&sk->sk_node, list);
819}
820
821static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
822{
823 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
824}
825
826static inline void __sk_nulls_add_node_tail_rcu(struct sock *sk, struct hlist_nulls_head *list)
827{
828 hlist_nulls_add_tail_rcu(&sk->sk_nulls_node, list);
829}
830
831static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
832{
833 sock_hold(sk);
834 __sk_nulls_add_node_rcu(sk, list);
835}
836
837static inline void __sk_del_bind_node(struct sock *sk)
838{
839 __hlist_del(&sk->sk_bind_node);
840}
841
842static inline void sk_add_bind_node(struct sock *sk,
843 struct hlist_head *list)
844{
845 hlist_add_head(&sk->sk_bind_node, list);
846}
847
848#define sk_for_each(__sk, list) \
849 hlist_for_each_entry(__sk, list, sk_node)
850#define sk_for_each_rcu(__sk, list) \
851 hlist_for_each_entry_rcu(__sk, list, sk_node)
852#define sk_nulls_for_each(__sk, node, list) \
853 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
854#define sk_nulls_for_each_rcu(__sk, node, list) \
855 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
856#define sk_for_each_from(__sk) \
857 hlist_for_each_entry_from(__sk, sk_node)
858#define sk_nulls_for_each_from(__sk, node) \
859 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
860 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
861#define sk_for_each_safe(__sk, tmp, list) \
862 hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
863#define sk_for_each_bound(__sk, list) \
864 hlist_for_each_entry(__sk, list, sk_bind_node)
865
866/**
867 * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset
868 * @tpos: the type * to use as a loop cursor.
869 * @pos: the &struct hlist_node to use as a loop cursor.
870 * @head: the head for your list.
871 * @offset: offset of hlist_node within the struct.
872 *
873 */
874#define sk_for_each_entry_offset_rcu(tpos, pos, head, offset) \
875 for (pos = rcu_dereference(hlist_first_rcu(head)); \
876 pos != NULL && \
877 ({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \
878 pos = rcu_dereference(hlist_next_rcu(pos)))
879
880static inline struct user_namespace *sk_user_ns(const struct sock *sk)
881{
882 /* Careful only use this in a context where these parameters
883 * can not change and must all be valid, such as recvmsg from
884 * userspace.
885 */
886 return sk->sk_socket->file->f_cred->user_ns;
887}
888
889/* Sock flags */
890enum sock_flags {
891 SOCK_DEAD,
892 SOCK_DONE,
893 SOCK_URGINLINE,
894 SOCK_KEEPOPEN,
895 SOCK_LINGER,
896 SOCK_DESTROY,
897 SOCK_BROADCAST,
898 SOCK_TIMESTAMP,
899 SOCK_ZAPPED,
900 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
901 SOCK_DBG, /* %SO_DEBUG setting */
902 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
903 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
904 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
905 SOCK_MEMALLOC, /* VM depends on this socket for swapping */
906 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */
907 SOCK_FASYNC, /* fasync() active */
908 SOCK_RXQ_OVFL,
909 SOCK_ZEROCOPY, /* buffers from userspace */
910 SOCK_WIFI_STATUS, /* push wifi status to userspace */
911 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
912 * Will use last 4 bytes of packet sent from
913 * user-space instead.
914 */
915 SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
916 SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
917 SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */
918 SOCK_TXTIME,
919 SOCK_XDP, /* XDP is attached */
920 SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */
921 SOCK_RCVMARK, /* Receive SO_MARK ancillary data with packet */
922};
923
924#define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
925
926static inline void sock_copy_flags(struct sock *nsk, const struct sock *osk)
927{
928 nsk->sk_flags = osk->sk_flags;
929}
930
931static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
932{
933 __set_bit(flag, &sk->sk_flags);
934}
935
936static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
937{
938 __clear_bit(flag, &sk->sk_flags);
939}
940
941static inline void sock_valbool_flag(struct sock *sk, enum sock_flags bit,
942 int valbool)
943{
944 if (valbool)
945 sock_set_flag(sk, bit);
946 else
947 sock_reset_flag(sk, bit);
948}
949
950static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
951{
952 return test_bit(flag, &sk->sk_flags);
953}
954
955#ifdef CONFIG_NET
956DECLARE_STATIC_KEY_FALSE(memalloc_socks_key);
957static inline int sk_memalloc_socks(void)
958{
959 return static_branch_unlikely(&memalloc_socks_key);
960}
961
962void __receive_sock(struct file *file);
963#else
964
965static inline int sk_memalloc_socks(void)
966{
967 return 0;
968}
969
970static inline void __receive_sock(struct file *file)
971{ }
972#endif
973
974static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask)
975{
976 return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC);
977}
978
979static inline void sk_acceptq_removed(struct sock *sk)
980{
981 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1);
982}
983
984static inline void sk_acceptq_added(struct sock *sk)
985{
986 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1);
987}
988
989/* Note: If you think the test should be:
990 * return READ_ONCE(sk->sk_ack_backlog) >= READ_ONCE(sk->sk_max_ack_backlog);
991 * Then please take a look at commit 64a146513f8f ("[NET]: Revert incorrect accept queue backlog changes.")
992 */
993static inline bool sk_acceptq_is_full(const struct sock *sk)
994{
995 return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(sk->sk_max_ack_backlog);
996}
997
998/*
999 * Compute minimal free write space needed to queue new packets.
1000 */
1001static inline int sk_stream_min_wspace(const struct sock *sk)
1002{
1003 return READ_ONCE(sk->sk_wmem_queued) >> 1;
1004}
1005
1006static inline int sk_stream_wspace(const struct sock *sk)
1007{
1008 return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued);
1009}
1010
1011static inline void sk_wmem_queued_add(struct sock *sk, int val)
1012{
1013 WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val);
1014}
1015
1016void sk_stream_write_space(struct sock *sk);
1017
1018/* OOB backlog add */
1019static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
1020{
1021 /* dont let skb dst not refcounted, we are going to leave rcu lock */
1022 skb_dst_force(skb);
1023
1024 if (!sk->sk_backlog.tail)
1025 WRITE_ONCE(sk->sk_backlog.head, skb);
1026 else
1027 sk->sk_backlog.tail->next = skb;
1028
1029 WRITE_ONCE(sk->sk_backlog.tail, skb);
1030 skb->next = NULL;
1031}
1032
1033/*
1034 * Take into account size of receive queue and backlog queue
1035 * Do not take into account this skb truesize,
1036 * to allow even a single big packet to come.
1037 */
1038static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
1039{
1040 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
1041
1042 return qsize > limit;
1043}
1044
1045/* The per-socket spinlock must be held here. */
1046static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
1047 unsigned int limit)
1048{
1049 if (sk_rcvqueues_full(sk, limit))
1050 return -ENOBUFS;
1051
1052 /*
1053 * If the skb was allocated from pfmemalloc reserves, only
1054 * allow SOCK_MEMALLOC sockets to use it as this socket is
1055 * helping free memory
1056 */
1057 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC))
1058 return -ENOMEM;
1059
1060 __sk_add_backlog(sk, skb);
1061 sk->sk_backlog.len += skb->truesize;
1062 return 0;
1063}
1064
1065int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
1066
1067INDIRECT_CALLABLE_DECLARE(int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb));
1068INDIRECT_CALLABLE_DECLARE(int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb));
1069
1070static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
1071{
1072 if (sk_memalloc_socks() && skb_pfmemalloc(skb))
1073 return __sk_backlog_rcv(sk, skb);
1074
1075 return INDIRECT_CALL_INET(sk->sk_backlog_rcv,
1076 tcp_v6_do_rcv,
1077 tcp_v4_do_rcv,
1078 sk, skb);
1079}
1080
1081static inline void sk_incoming_cpu_update(struct sock *sk)
1082{
1083 int cpu = raw_smp_processor_id();
1084
1085 if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu))
1086 WRITE_ONCE(sk->sk_incoming_cpu, cpu);
1087}
1088
1089static inline void sock_rps_record_flow_hash(__u32 hash)
1090{
1091#ifdef CONFIG_RPS
1092 struct rps_sock_flow_table *sock_flow_table;
1093
1094 rcu_read_lock();
1095 sock_flow_table = rcu_dereference(rps_sock_flow_table);
1096 rps_record_sock_flow(sock_flow_table, hash);
1097 rcu_read_unlock();
1098#endif
1099}
1100
1101static inline void sock_rps_record_flow(const struct sock *sk)
1102{
1103#ifdef CONFIG_RPS
1104 if (static_branch_unlikely(&rfs_needed)) {
1105 /* Reading sk->sk_rxhash might incur an expensive cache line
1106 * miss.
1107 *
1108 * TCP_ESTABLISHED does cover almost all states where RFS
1109 * might be useful, and is cheaper [1] than testing :
1110 * IPv4: inet_sk(sk)->inet_daddr
1111 * IPv6: ipv6_addr_any(&sk->sk_v6_daddr)
1112 * OR an additional socket flag
1113 * [1] : sk_state and sk_prot are in the same cache line.
1114 */
1115 if (sk->sk_state == TCP_ESTABLISHED)
1116 sock_rps_record_flow_hash(sk->sk_rxhash);
1117 }
1118#endif
1119}
1120
1121static inline void sock_rps_save_rxhash(struct sock *sk,
1122 const struct sk_buff *skb)
1123{
1124#ifdef CONFIG_RPS
1125 if (unlikely(sk->sk_rxhash != skb->hash))
1126 sk->sk_rxhash = skb->hash;
1127#endif
1128}
1129
1130static inline void sock_rps_reset_rxhash(struct sock *sk)
1131{
1132#ifdef CONFIG_RPS
1133 sk->sk_rxhash = 0;
1134#endif
1135}
1136
1137#define sk_wait_event(__sk, __timeo, __condition, __wait) \
1138 ({ int __rc; \
1139 release_sock(__sk); \
1140 __rc = __condition; \
1141 if (!__rc) { \
1142 *(__timeo) = wait_woken(__wait, \
1143 TASK_INTERRUPTIBLE, \
1144 *(__timeo)); \
1145 } \
1146 sched_annotate_sleep(); \
1147 lock_sock(__sk); \
1148 __rc = __condition; \
1149 __rc; \
1150 })
1151
1152int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
1153int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
1154void sk_stream_wait_close(struct sock *sk, long timeo_p);
1155int sk_stream_error(struct sock *sk, int flags, int err);
1156void sk_stream_kill_queues(struct sock *sk);
1157void sk_set_memalloc(struct sock *sk);
1158void sk_clear_memalloc(struct sock *sk);
1159
1160void __sk_flush_backlog(struct sock *sk);
1161
1162static inline bool sk_flush_backlog(struct sock *sk)
1163{
1164 if (unlikely(READ_ONCE(sk->sk_backlog.tail))) {
1165 __sk_flush_backlog(sk);
1166 return true;
1167 }
1168 return false;
1169}
1170
1171int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb);
1172
1173struct request_sock_ops;
1174struct timewait_sock_ops;
1175struct inet_hashinfo;
1176struct raw_hashinfo;
1177struct smc_hashinfo;
1178struct module;
1179struct sk_psock;
1180
1181/*
1182 * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes
1183 * un-modified. Special care is taken when initializing object to zero.
1184 */
1185static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1186{
1187 if (offsetof(struct sock, sk_node.next) != 0)
1188 memset(sk, 0, offsetof(struct sock, sk_node.next));
1189 memset(&sk->sk_node.pprev, 0,
1190 size - offsetof(struct sock, sk_node.pprev));
1191}
1192
1193/* Networking protocol blocks we attach to sockets.
1194 * socket layer -> transport layer interface
1195 */
1196struct proto {
1197 void (*close)(struct sock *sk,
1198 long timeout);
1199 int (*pre_connect)(struct sock *sk,
1200 struct sockaddr *uaddr,
1201 int addr_len);
1202 int (*connect)(struct sock *sk,
1203 struct sockaddr *uaddr,
1204 int addr_len);
1205 int (*disconnect)(struct sock *sk, int flags);
1206
1207 struct sock * (*accept)(struct sock *sk, int flags, int *err,
1208 bool kern);
1209
1210 int (*ioctl)(struct sock *sk, int cmd,
1211 unsigned long arg);
1212 int (*init)(struct sock *sk);
1213 void (*destroy)(struct sock *sk);
1214 void (*shutdown)(struct sock *sk, int how);
1215 int (*setsockopt)(struct sock *sk, int level,
1216 int optname, sockptr_t optval,
1217 unsigned int optlen);
1218 int (*getsockopt)(struct sock *sk, int level,
1219 int optname, char __user *optval,
1220 int __user *option);
1221 void (*keepalive)(struct sock *sk, int valbool);
1222#ifdef CONFIG_COMPAT
1223 int (*compat_ioctl)(struct sock *sk,
1224 unsigned int cmd, unsigned long arg);
1225#endif
1226 int (*sendmsg)(struct sock *sk, struct msghdr *msg,
1227 size_t len);
1228 int (*recvmsg)(struct sock *sk, struct msghdr *msg,
1229 size_t len, int flags, int *addr_len);
1230 int (*sendpage)(struct sock *sk, struct page *page,
1231 int offset, size_t size, int flags);
1232 int (*bind)(struct sock *sk,
1233 struct sockaddr *addr, int addr_len);
1234 int (*bind_add)(struct sock *sk,
1235 struct sockaddr *addr, int addr_len);
1236
1237 int (*backlog_rcv) (struct sock *sk,
1238 struct sk_buff *skb);
1239 bool (*bpf_bypass_getsockopt)(int level,
1240 int optname);
1241
1242 void (*release_cb)(struct sock *sk);
1243
1244 /* Keeping track of sk's, looking them up, and port selection methods. */
1245 int (*hash)(struct sock *sk);
1246 void (*unhash)(struct sock *sk);
1247 void (*rehash)(struct sock *sk);
1248 int (*get_port)(struct sock *sk, unsigned short snum);
1249 void (*put_port)(struct sock *sk);
1250#ifdef CONFIG_BPF_SYSCALL
1251 int (*psock_update_sk_prot)(struct sock *sk,
1252 struct sk_psock *psock,
1253 bool restore);
1254#endif
1255
1256 /* Keeping track of sockets in use */
1257#ifdef CONFIG_PROC_FS
1258 unsigned int inuse_idx;
1259#endif
1260
1261#if IS_ENABLED(CONFIG_MPTCP)
1262 int (*forward_alloc_get)(const struct sock *sk);
1263#endif
1264
1265 bool (*stream_memory_free)(const struct sock *sk, int wake);
1266 bool (*sock_is_readable)(struct sock *sk);
1267 /* Memory pressure */
1268 void (*enter_memory_pressure)(struct sock *sk);
1269 void (*leave_memory_pressure)(struct sock *sk);
1270 atomic_long_t *memory_allocated; /* Current allocated memory. */
1271 int __percpu *per_cpu_fw_alloc;
1272 struct percpu_counter *sockets_allocated; /* Current number of sockets. */
1273
1274 /*
1275 * Pressure flag: try to collapse.
1276 * Technical note: it is used by multiple contexts non atomically.
1277 * All the __sk_mem_schedule() is of this nature: accounting
1278 * is strict, actions are advisory and have some latency.
1279 */
1280 unsigned long *memory_pressure;
1281 long *sysctl_mem;
1282
1283 int *sysctl_wmem;
1284 int *sysctl_rmem;
1285 u32 sysctl_wmem_offset;
1286 u32 sysctl_rmem_offset;
1287
1288 int max_header;
1289 bool no_autobind;
1290
1291 struct kmem_cache *slab;
1292 unsigned int obj_size;
1293 slab_flags_t slab_flags;
1294 unsigned int useroffset; /* Usercopy region offset */
1295 unsigned int usersize; /* Usercopy region size */
1296
1297 unsigned int __percpu *orphan_count;
1298
1299 struct request_sock_ops *rsk_prot;
1300 struct timewait_sock_ops *twsk_prot;
1301
1302 union {
1303 struct inet_hashinfo *hashinfo;
1304 struct udp_table *udp_table;
1305 struct raw_hashinfo *raw_hash;
1306 struct smc_hashinfo *smc_hash;
1307 } h;
1308
1309 struct module *owner;
1310
1311 char name[32];
1312
1313 struct list_head node;
1314#ifdef SOCK_REFCNT_DEBUG
1315 atomic_t socks;
1316#endif
1317 int (*diag_destroy)(struct sock *sk, int err);
1318} __randomize_layout;
1319
1320int proto_register(struct proto *prot, int alloc_slab);
1321void proto_unregister(struct proto *prot);
1322int sock_load_diag_module(int family, int protocol);
1323
1324#ifdef SOCK_REFCNT_DEBUG
1325static inline void sk_refcnt_debug_inc(struct sock *sk)
1326{
1327 atomic_inc(&sk->sk_prot->socks);
1328}
1329
1330static inline void sk_refcnt_debug_dec(struct sock *sk)
1331{
1332 atomic_dec(&sk->sk_prot->socks);
1333 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
1334 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
1335}
1336
1337static inline void sk_refcnt_debug_release(const struct sock *sk)
1338{
1339 if (refcount_read(&sk->sk_refcnt) != 1)
1340 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
1341 sk->sk_prot->name, sk, refcount_read(&sk->sk_refcnt));
1342}
1343#else /* SOCK_REFCNT_DEBUG */
1344#define sk_refcnt_debug_inc(sk) do { } while (0)
1345#define sk_refcnt_debug_dec(sk) do { } while (0)
1346#define sk_refcnt_debug_release(sk) do { } while (0)
1347#endif /* SOCK_REFCNT_DEBUG */
1348
1349INDIRECT_CALLABLE_DECLARE(bool tcp_stream_memory_free(const struct sock *sk, int wake));
1350
1351static inline int sk_forward_alloc_get(const struct sock *sk)
1352{
1353#if IS_ENABLED(CONFIG_MPTCP)
1354 if (sk->sk_prot->forward_alloc_get)
1355 return sk->sk_prot->forward_alloc_get(sk);
1356#endif
1357 return sk->sk_forward_alloc;
1358}
1359
1360static inline bool __sk_stream_memory_free(const struct sock *sk, int wake)
1361{
1362 if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf))
1363 return false;
1364
1365 return sk->sk_prot->stream_memory_free ?
1366 INDIRECT_CALL_INET_1(sk->sk_prot->stream_memory_free,
1367 tcp_stream_memory_free, sk, wake) : true;
1368}
1369
1370static inline bool sk_stream_memory_free(const struct sock *sk)
1371{
1372 return __sk_stream_memory_free(sk, 0);
1373}
1374
1375static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake)
1376{
1377 return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
1378 __sk_stream_memory_free(sk, wake);
1379}
1380
1381static inline bool sk_stream_is_writeable(const struct sock *sk)
1382{
1383 return __sk_stream_is_writeable(sk, 0);
1384}
1385
1386static inline int sk_under_cgroup_hierarchy(struct sock *sk,
1387 struct cgroup *ancestor)
1388{
1389#ifdef CONFIG_SOCK_CGROUP_DATA
1390 return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data),
1391 ancestor);
1392#else
1393 return -ENOTSUPP;
1394#endif
1395}
1396
1397static inline bool sk_has_memory_pressure(const struct sock *sk)
1398{
1399 return sk->sk_prot->memory_pressure != NULL;
1400}
1401
1402static inline bool sk_under_memory_pressure(const struct sock *sk)
1403{
1404 if (!sk->sk_prot->memory_pressure)
1405 return false;
1406
1407 if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
1408 mem_cgroup_under_socket_pressure(sk->sk_memcg))
1409 return true;
1410
1411 return !!*sk->sk_prot->memory_pressure;
1412}
1413
1414static inline long
1415proto_memory_allocated(const struct proto *prot)
1416{
1417 return max(0L, atomic_long_read(prot->memory_allocated));
1418}
1419
1420static inline long
1421sk_memory_allocated(const struct sock *sk)
1422{
1423 return proto_memory_allocated(sk->sk_prot);
1424}
1425
1426/* 1 MB per cpu, in page units */
1427#define SK_MEMORY_PCPU_RESERVE (1 << (20 - PAGE_SHIFT))
1428
1429static inline void
1430sk_memory_allocated_add(struct sock *sk, int amt)
1431{
1432 int local_reserve;
1433
1434 preempt_disable();
1435 local_reserve = __this_cpu_add_return(*sk->sk_prot->per_cpu_fw_alloc, amt);
1436 if (local_reserve >= SK_MEMORY_PCPU_RESERVE) {
1437 __this_cpu_sub(*sk->sk_prot->per_cpu_fw_alloc, local_reserve);
1438 atomic_long_add(local_reserve, sk->sk_prot->memory_allocated);
1439 }
1440 preempt_enable();
1441}
1442
1443static inline void
1444sk_memory_allocated_sub(struct sock *sk, int amt)
1445{
1446 int local_reserve;
1447
1448 preempt_disable();
1449 local_reserve = __this_cpu_sub_return(*sk->sk_prot->per_cpu_fw_alloc, amt);
1450 if (local_reserve <= -SK_MEMORY_PCPU_RESERVE) {
1451 __this_cpu_sub(*sk->sk_prot->per_cpu_fw_alloc, local_reserve);
1452 atomic_long_add(local_reserve, sk->sk_prot->memory_allocated);
1453 }
1454 preempt_enable();
1455}
1456
1457#define SK_ALLOC_PERCPU_COUNTER_BATCH 16
1458
1459static inline void sk_sockets_allocated_dec(struct sock *sk)
1460{
1461 percpu_counter_add_batch(sk->sk_prot->sockets_allocated, -1,
1462 SK_ALLOC_PERCPU_COUNTER_BATCH);
1463}
1464
1465static inline void sk_sockets_allocated_inc(struct sock *sk)
1466{
1467 percpu_counter_add_batch(sk->sk_prot->sockets_allocated, 1,
1468 SK_ALLOC_PERCPU_COUNTER_BATCH);
1469}
1470
1471static inline u64
1472sk_sockets_allocated_read_positive(struct sock *sk)
1473{
1474 return percpu_counter_read_positive(sk->sk_prot->sockets_allocated);
1475}
1476
1477static inline int
1478proto_sockets_allocated_sum_positive(struct proto *prot)
1479{
1480 return percpu_counter_sum_positive(prot->sockets_allocated);
1481}
1482
1483static inline bool
1484proto_memory_pressure(struct proto *prot)
1485{
1486 if (!prot->memory_pressure)
1487 return false;
1488 return !!*prot->memory_pressure;
1489}
1490
1491
1492#ifdef CONFIG_PROC_FS
1493#define PROTO_INUSE_NR 64 /* should be enough for the first time */
1494struct prot_inuse {
1495 int all;
1496 int val[PROTO_INUSE_NR];
1497};
1498
1499static inline void sock_prot_inuse_add(const struct net *net,
1500 const struct proto *prot, int val)
1501{
1502 this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val);
1503}
1504
1505static inline void sock_inuse_add(const struct net *net, int val)
1506{
1507 this_cpu_add(net->core.prot_inuse->all, val);
1508}
1509
1510int sock_prot_inuse_get(struct net *net, struct proto *proto);
1511int sock_inuse_get(struct net *net);
1512#else
1513static inline void sock_prot_inuse_add(const struct net *net,
1514 const struct proto *prot, int val)
1515{
1516}
1517
1518static inline void sock_inuse_add(const struct net *net, int val)
1519{
1520}
1521#endif
1522
1523
1524/* With per-bucket locks this operation is not-atomic, so that
1525 * this version is not worse.
1526 */
1527static inline int __sk_prot_rehash(struct sock *sk)
1528{
1529 sk->sk_prot->unhash(sk);
1530 return sk->sk_prot->hash(sk);
1531}
1532
1533/* About 10 seconds */
1534#define SOCK_DESTROY_TIME (10*HZ)
1535
1536/* Sockets 0-1023 can't be bound to unless you are superuser */
1537#define PROT_SOCK 1024
1538
1539#define SHUTDOWN_MASK 3
1540#define RCV_SHUTDOWN 1
1541#define SEND_SHUTDOWN 2
1542
1543#define SOCK_BINDADDR_LOCK 4
1544#define SOCK_BINDPORT_LOCK 8
1545
1546struct socket_alloc {
1547 struct socket socket;
1548 struct inode vfs_inode;
1549};
1550
1551static inline struct socket *SOCKET_I(struct inode *inode)
1552{
1553 return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1554}
1555
1556static inline struct inode *SOCK_INODE(struct socket *socket)
1557{
1558 return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1559}
1560
1561/*
1562 * Functions for memory accounting
1563 */
1564int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind);
1565int __sk_mem_schedule(struct sock *sk, int size, int kind);
1566void __sk_mem_reduce_allocated(struct sock *sk, int amount);
1567void __sk_mem_reclaim(struct sock *sk, int amount);
1568
1569#define SK_MEM_SEND 0
1570#define SK_MEM_RECV 1
1571
1572/* sysctl_mem values are in pages */
1573static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1574{
1575 return READ_ONCE(sk->sk_prot->sysctl_mem[index]);
1576}
1577
1578static inline int sk_mem_pages(int amt)
1579{
1580 return (amt + PAGE_SIZE - 1) >> PAGE_SHIFT;
1581}
1582
1583static inline bool sk_has_account(struct sock *sk)
1584{
1585 /* return true if protocol supports memory accounting */
1586 return !!sk->sk_prot->memory_allocated;
1587}
1588
1589static inline bool sk_wmem_schedule(struct sock *sk, int size)
1590{
1591 int delta;
1592
1593 if (!sk_has_account(sk))
1594 return true;
1595 delta = size - sk->sk_forward_alloc;
1596 return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_SEND);
1597}
1598
1599static inline bool
1600sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
1601{
1602 int delta;
1603
1604 if (!sk_has_account(sk))
1605 return true;
1606 delta = size - sk->sk_forward_alloc;
1607 return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_RECV) ||
1608 skb_pfmemalloc(skb);
1609}
1610
1611static inline int sk_unused_reserved_mem(const struct sock *sk)
1612{
1613 int unused_mem;
1614
1615 if (likely(!sk->sk_reserved_mem))
1616 return 0;
1617
1618 unused_mem = sk->sk_reserved_mem - sk->sk_wmem_queued -
1619 atomic_read(&sk->sk_rmem_alloc);
1620
1621 return unused_mem > 0 ? unused_mem : 0;
1622}
1623
1624static inline void sk_mem_reclaim(struct sock *sk)
1625{
1626 int reclaimable;
1627
1628 if (!sk_has_account(sk))
1629 return;
1630
1631 reclaimable = sk->sk_forward_alloc - sk_unused_reserved_mem(sk);
1632
1633 if (reclaimable >= (int)PAGE_SIZE)
1634 __sk_mem_reclaim(sk, reclaimable);
1635}
1636
1637static inline void sk_mem_reclaim_final(struct sock *sk)
1638{
1639 sk->sk_reserved_mem = 0;
1640 sk_mem_reclaim(sk);
1641}
1642
1643static inline void sk_mem_charge(struct sock *sk, int size)
1644{
1645 if (!sk_has_account(sk))
1646 return;
1647 sk->sk_forward_alloc -= size;
1648}
1649
1650static inline void sk_mem_uncharge(struct sock *sk, int size)
1651{
1652 if (!sk_has_account(sk))
1653 return;
1654 sk->sk_forward_alloc += size;
1655 sk_mem_reclaim(sk);
1656}
1657
1658/*
1659 * Macro so as to not evaluate some arguments when
1660 * lockdep is not enabled.
1661 *
1662 * Mark both the sk_lock and the sk_lock.slock as a
1663 * per-address-family lock class.
1664 */
1665#define sock_lock_init_class_and_name(sk, sname, skey, name, key) \
1666do { \
1667 sk->sk_lock.owned = 0; \
1668 init_waitqueue_head(&sk->sk_lock.wq); \
1669 spin_lock_init(&(sk)->sk_lock.slock); \
1670 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \
1671 sizeof((sk)->sk_lock)); \
1672 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \
1673 (skey), (sname)); \
1674 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \
1675} while (0)
1676
1677static inline bool lockdep_sock_is_held(const struct sock *sk)
1678{
1679 return lockdep_is_held(&sk->sk_lock) ||
1680 lockdep_is_held(&sk->sk_lock.slock);
1681}
1682
1683void lock_sock_nested(struct sock *sk, int subclass);
1684
1685static inline void lock_sock(struct sock *sk)
1686{
1687 lock_sock_nested(sk, 0);
1688}
1689
1690void __lock_sock(struct sock *sk);
1691void __release_sock(struct sock *sk);
1692void release_sock(struct sock *sk);
1693
1694/* BH context may only use the following locking interface. */
1695#define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock))
1696#define bh_lock_sock_nested(__sk) \
1697 spin_lock_nested(&((__sk)->sk_lock.slock), \
1698 SINGLE_DEPTH_NESTING)
1699#define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock))
1700
1701bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock);
1702
1703/**
1704 * lock_sock_fast - fast version of lock_sock
1705 * @sk: socket
1706 *
1707 * This version should be used for very small section, where process wont block
1708 * return false if fast path is taken:
1709 *
1710 * sk_lock.slock locked, owned = 0, BH disabled
1711 *
1712 * return true if slow path is taken:
1713 *
1714 * sk_lock.slock unlocked, owned = 1, BH enabled
1715 */
1716static inline bool lock_sock_fast(struct sock *sk)
1717{
1718 /* The sk_lock has mutex_lock() semantics here. */
1719 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
1720
1721 return __lock_sock_fast(sk);
1722}
1723
1724/* fast socket lock variant for caller already holding a [different] socket lock */
1725static inline bool lock_sock_fast_nested(struct sock *sk)
1726{
1727 mutex_acquire(&sk->sk_lock.dep_map, SINGLE_DEPTH_NESTING, 0, _RET_IP_);
1728
1729 return __lock_sock_fast(sk);
1730}
1731
1732/**
1733 * unlock_sock_fast - complement of lock_sock_fast
1734 * @sk: socket
1735 * @slow: slow mode
1736 *
1737 * fast unlock socket for user context.
1738 * If slow mode is on, we call regular release_sock()
1739 */
1740static inline void unlock_sock_fast(struct sock *sk, bool slow)
1741 __releases(&sk->sk_lock.slock)
1742{
1743 if (slow) {
1744 release_sock(sk);
1745 __release(&sk->sk_lock.slock);
1746 } else {
1747 mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1748 spin_unlock_bh(&sk->sk_lock.slock);
1749 }
1750}
1751
1752/* Used by processes to "lock" a socket state, so that
1753 * interrupts and bottom half handlers won't change it
1754 * from under us. It essentially blocks any incoming
1755 * packets, so that we won't get any new data or any
1756 * packets that change the state of the socket.
1757 *
1758 * While locked, BH processing will add new packets to
1759 * the backlog queue. This queue is processed by the
1760 * owner of the socket lock right before it is released.
1761 *
1762 * Since ~2.3.5 it is also exclusive sleep lock serializing
1763 * accesses from user process context.
1764 */
1765
1766static inline void sock_owned_by_me(const struct sock *sk)
1767{
1768#ifdef CONFIG_LOCKDEP
1769 WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
1770#endif
1771}
1772
1773static inline bool sock_owned_by_user(const struct sock *sk)
1774{
1775 sock_owned_by_me(sk);
1776 return sk->sk_lock.owned;
1777}
1778
1779static inline bool sock_owned_by_user_nocheck(const struct sock *sk)
1780{
1781 return sk->sk_lock.owned;
1782}
1783
1784static inline void sock_release_ownership(struct sock *sk)
1785{
1786 if (sock_owned_by_user_nocheck(sk)) {
1787 sk->sk_lock.owned = 0;
1788
1789 /* The sk_lock has mutex_unlock() semantics: */
1790 mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1791 }
1792}
1793
1794/* no reclassification while locks are held */
1795static inline bool sock_allow_reclassification(const struct sock *csk)
1796{
1797 struct sock *sk = (struct sock *)csk;
1798
1799 return !sock_owned_by_user_nocheck(sk) &&
1800 !spin_is_locked(&sk->sk_lock.slock);
1801}
1802
1803struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1804 struct proto *prot, int kern);
1805void sk_free(struct sock *sk);
1806void sk_destruct(struct sock *sk);
1807struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
1808void sk_free_unlock_clone(struct sock *sk);
1809
1810struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1811 gfp_t priority);
1812void __sock_wfree(struct sk_buff *skb);
1813void sock_wfree(struct sk_buff *skb);
1814struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1815 gfp_t priority);
1816void skb_orphan_partial(struct sk_buff *skb);
1817void sock_rfree(struct sk_buff *skb);
1818void sock_efree(struct sk_buff *skb);
1819#ifdef CONFIG_INET
1820void sock_edemux(struct sk_buff *skb);
1821void sock_pfree(struct sk_buff *skb);
1822#else
1823#define sock_edemux sock_efree
1824#endif
1825
1826int sock_setsockopt(struct socket *sock, int level, int op,
1827 sockptr_t optval, unsigned int optlen);
1828
1829int sock_getsockopt(struct socket *sock, int level, int op,
1830 char __user *optval, int __user *optlen);
1831int sock_gettstamp(struct socket *sock, void __user *userstamp,
1832 bool timeval, bool time32);
1833struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1834 unsigned long data_len, int noblock,
1835 int *errcode, int max_page_order);
1836
1837static inline struct sk_buff *sock_alloc_send_skb(struct sock *sk,
1838 unsigned long size,
1839 int noblock, int *errcode)
1840{
1841 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
1842}
1843
1844void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
1845void sock_kfree_s(struct sock *sk, void *mem, int size);
1846void sock_kzfree_s(struct sock *sk, void *mem, int size);
1847void sk_send_sigurg(struct sock *sk);
1848
1849struct sockcm_cookie {
1850 u64 transmit_time;
1851 u32 mark;
1852 u16 tsflags;
1853};
1854
1855static inline void sockcm_init(struct sockcm_cookie *sockc,
1856 const struct sock *sk)
1857{
1858 *sockc = (struct sockcm_cookie) { .tsflags = sk->sk_tsflags };
1859}
1860
1861int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
1862 struct sockcm_cookie *sockc);
1863int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1864 struct sockcm_cookie *sockc);
1865
1866/*
1867 * Functions to fill in entries in struct proto_ops when a protocol
1868 * does not implement a particular function.
1869 */
1870int sock_no_bind(struct socket *, struct sockaddr *, int);
1871int sock_no_connect(struct socket *, struct sockaddr *, int, int);
1872int sock_no_socketpair(struct socket *, struct socket *);
1873int sock_no_accept(struct socket *, struct socket *, int, bool);
1874int sock_no_getname(struct socket *, struct sockaddr *, int);
1875int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
1876int sock_no_listen(struct socket *, int);
1877int sock_no_shutdown(struct socket *, int);
1878int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
1879int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
1880int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
1881int sock_no_mmap(struct file *file, struct socket *sock,
1882 struct vm_area_struct *vma);
1883ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset,
1884 size_t size, int flags);
1885ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
1886 int offset, size_t size, int flags);
1887
1888/*
1889 * Functions to fill in entries in struct proto_ops when a protocol
1890 * uses the inet style.
1891 */
1892int sock_common_getsockopt(struct socket *sock, int level, int optname,
1893 char __user *optval, int __user *optlen);
1894int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1895 int flags);
1896int sock_common_setsockopt(struct socket *sock, int level, int optname,
1897 sockptr_t optval, unsigned int optlen);
1898
1899void sk_common_release(struct sock *sk);
1900
1901/*
1902 * Default socket callbacks and setup code
1903 */
1904
1905/* Initialise core socket variables */
1906void sock_init_data(struct socket *sock, struct sock *sk);
1907
1908/*
1909 * Socket reference counting postulates.
1910 *
1911 * * Each user of socket SHOULD hold a reference count.
1912 * * Each access point to socket (an hash table bucket, reference from a list,
1913 * running timer, skb in flight MUST hold a reference count.
1914 * * When reference count hits 0, it means it will never increase back.
1915 * * When reference count hits 0, it means that no references from
1916 * outside exist to this socket and current process on current CPU
1917 * is last user and may/should destroy this socket.
1918 * * sk_free is called from any context: process, BH, IRQ. When
1919 * it is called, socket has no references from outside -> sk_free
1920 * may release descendant resources allocated by the socket, but
1921 * to the time when it is called, socket is NOT referenced by any
1922 * hash tables, lists etc.
1923 * * Packets, delivered from outside (from network or from another process)
1924 * and enqueued on receive/error queues SHOULD NOT grab reference count,
1925 * when they sit in queue. Otherwise, packets will leak to hole, when
1926 * socket is looked up by one cpu and unhasing is made by another CPU.
1927 * It is true for udp/raw, netlink (leak to receive and error queues), tcp
1928 * (leak to backlog). Packet socket does all the processing inside
1929 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1930 * use separate SMP lock, so that they are prone too.
1931 */
1932
1933/* Ungrab socket and destroy it, if it was the last reference. */
1934static inline void sock_put(struct sock *sk)
1935{
1936 if (refcount_dec_and_test(&sk->sk_refcnt))
1937 sk_free(sk);
1938}
1939/* Generic version of sock_put(), dealing with all sockets
1940 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
1941 */
1942void sock_gen_put(struct sock *sk);
1943
1944int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested,
1945 unsigned int trim_cap, bool refcounted);
1946static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1947 const int nested)
1948{
1949 return __sk_receive_skb(sk, skb, nested, 1, true);
1950}
1951
1952static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1953{
1954 /* sk_tx_queue_mapping accept only upto a 16-bit value */
1955 if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX))
1956 return;
1957 sk->sk_tx_queue_mapping = tx_queue;
1958}
1959
1960#define NO_QUEUE_MAPPING USHRT_MAX
1961
1962static inline void sk_tx_queue_clear(struct sock *sk)
1963{
1964 sk->sk_tx_queue_mapping = NO_QUEUE_MAPPING;
1965}
1966
1967static inline int sk_tx_queue_get(const struct sock *sk)
1968{
1969 if (sk && sk->sk_tx_queue_mapping != NO_QUEUE_MAPPING)
1970 return sk->sk_tx_queue_mapping;
1971
1972 return -1;
1973}
1974
1975static inline void __sk_rx_queue_set(struct sock *sk,
1976 const struct sk_buff *skb,
1977 bool force_set)
1978{
1979#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1980 if (skb_rx_queue_recorded(skb)) {
1981 u16 rx_queue = skb_get_rx_queue(skb);
1982
1983 if (force_set ||
1984 unlikely(READ_ONCE(sk->sk_rx_queue_mapping) != rx_queue))
1985 WRITE_ONCE(sk->sk_rx_queue_mapping, rx_queue);
1986 }
1987#endif
1988}
1989
1990static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb)
1991{
1992 __sk_rx_queue_set(sk, skb, true);
1993}
1994
1995static inline void sk_rx_queue_update(struct sock *sk, const struct sk_buff *skb)
1996{
1997 __sk_rx_queue_set(sk, skb, false);
1998}
1999
2000static inline void sk_rx_queue_clear(struct sock *sk)
2001{
2002#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
2003 WRITE_ONCE(sk->sk_rx_queue_mapping, NO_QUEUE_MAPPING);
2004#endif
2005}
2006
2007static inline int sk_rx_queue_get(const struct sock *sk)
2008{
2009#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
2010 if (sk) {
2011 int res = READ_ONCE(sk->sk_rx_queue_mapping);
2012
2013 if (res != NO_QUEUE_MAPPING)
2014 return res;
2015 }
2016#endif
2017
2018 return -1;
2019}
2020
2021static inline void sk_set_socket(struct sock *sk, struct socket *sock)
2022{
2023 sk->sk_socket = sock;
2024}
2025
2026static inline wait_queue_head_t *sk_sleep(struct sock *sk)
2027{
2028 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
2029 return &rcu_dereference_raw(sk->sk_wq)->wait;
2030}
2031/* Detach socket from process context.
2032 * Announce socket dead, detach it from wait queue and inode.
2033 * Note that parent inode held reference count on this struct sock,
2034 * we do not release it in this function, because protocol
2035 * probably wants some additional cleanups or even continuing
2036 * to work with this socket (TCP).
2037 */
2038static inline void sock_orphan(struct sock *sk)
2039{
2040 write_lock_bh(&sk->sk_callback_lock);
2041 sock_set_flag(sk, SOCK_DEAD);
2042 sk_set_socket(sk, NULL);
2043 sk->sk_wq = NULL;
2044 write_unlock_bh(&sk->sk_callback_lock);
2045}
2046
2047static inline void sock_graft(struct sock *sk, struct socket *parent)
2048{
2049 WARN_ON(parent->sk);
2050 write_lock_bh(&sk->sk_callback_lock);
2051 rcu_assign_pointer(sk->sk_wq, &parent->wq);
2052 parent->sk = sk;
2053 sk_set_socket(sk, parent);
2054 sk->sk_uid = SOCK_INODE(parent)->i_uid;
2055 security_sock_graft(sk, parent);
2056 write_unlock_bh(&sk->sk_callback_lock);
2057}
2058
2059kuid_t sock_i_uid(struct sock *sk);
2060unsigned long sock_i_ino(struct sock *sk);
2061
2062static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk)
2063{
2064 return sk ? sk->sk_uid : make_kuid(net->user_ns, 0);
2065}
2066
2067static inline u32 net_tx_rndhash(void)
2068{
2069 u32 v = prandom_u32();
2070
2071 return v ?: 1;
2072}
2073
2074static inline void sk_set_txhash(struct sock *sk)
2075{
2076 /* This pairs with READ_ONCE() in skb_set_hash_from_sk() */
2077 WRITE_ONCE(sk->sk_txhash, net_tx_rndhash());
2078}
2079
2080static inline bool sk_rethink_txhash(struct sock *sk)
2081{
2082 if (sk->sk_txhash && sk->sk_txrehash == SOCK_TXREHASH_ENABLED) {
2083 sk_set_txhash(sk);
2084 return true;
2085 }
2086 return false;
2087}
2088
2089static inline struct dst_entry *
2090__sk_dst_get(struct sock *sk)
2091{
2092 return rcu_dereference_check(sk->sk_dst_cache,
2093 lockdep_sock_is_held(sk));
2094}
2095
2096static inline struct dst_entry *
2097sk_dst_get(struct sock *sk)
2098{
2099 struct dst_entry *dst;
2100
2101 rcu_read_lock();
2102 dst = rcu_dereference(sk->sk_dst_cache);
2103 if (dst && !atomic_inc_not_zero(&dst->__refcnt))
2104 dst = NULL;
2105 rcu_read_unlock();
2106 return dst;
2107}
2108
2109static inline void __dst_negative_advice(struct sock *sk)
2110{
2111 struct dst_entry *ndst, *dst = __sk_dst_get(sk);
2112
2113 if (dst && dst->ops->negative_advice) {
2114 ndst = dst->ops->negative_advice(dst);
2115
2116 if (ndst != dst) {
2117 rcu_assign_pointer(sk->sk_dst_cache, ndst);
2118 sk_tx_queue_clear(sk);
2119 sk->sk_dst_pending_confirm = 0;
2120 }
2121 }
2122}
2123
2124static inline void dst_negative_advice(struct sock *sk)
2125{
2126 sk_rethink_txhash(sk);
2127 __dst_negative_advice(sk);
2128}
2129
2130static inline void
2131__sk_dst_set(struct sock *sk, struct dst_entry *dst)
2132{
2133 struct dst_entry *old_dst;
2134
2135 sk_tx_queue_clear(sk);
2136 sk->sk_dst_pending_confirm = 0;
2137 old_dst = rcu_dereference_protected(sk->sk_dst_cache,
2138 lockdep_sock_is_held(sk));
2139 rcu_assign_pointer(sk->sk_dst_cache, dst);
2140 dst_release(old_dst);
2141}
2142
2143static inline void
2144sk_dst_set(struct sock *sk, struct dst_entry *dst)
2145{
2146 struct dst_entry *old_dst;
2147
2148 sk_tx_queue_clear(sk);
2149 sk->sk_dst_pending_confirm = 0;
2150 old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst);
2151 dst_release(old_dst);
2152}
2153
2154static inline void
2155__sk_dst_reset(struct sock *sk)
2156{
2157 __sk_dst_set(sk, NULL);
2158}
2159
2160static inline void
2161sk_dst_reset(struct sock *sk)
2162{
2163 sk_dst_set(sk, NULL);
2164}
2165
2166struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
2167
2168struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
2169
2170static inline void sk_dst_confirm(struct sock *sk)
2171{
2172 if (!READ_ONCE(sk->sk_dst_pending_confirm))
2173 WRITE_ONCE(sk->sk_dst_pending_confirm, 1);
2174}
2175
2176static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n)
2177{
2178 if (skb_get_dst_pending_confirm(skb)) {
2179 struct sock *sk = skb->sk;
2180
2181 if (sk && READ_ONCE(sk->sk_dst_pending_confirm))
2182 WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2183 neigh_confirm(n);
2184 }
2185}
2186
2187bool sk_mc_loop(struct sock *sk);
2188
2189static inline bool sk_can_gso(const struct sock *sk)
2190{
2191 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
2192}
2193
2194void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
2195
2196static inline void sk_gso_disable(struct sock *sk)
2197{
2198 sk->sk_gso_disabled = 1;
2199 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2200}
2201
2202static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
2203 struct iov_iter *from, char *to,
2204 int copy, int offset)
2205{
2206 if (skb->ip_summed == CHECKSUM_NONE) {
2207 __wsum csum = 0;
2208 if (!csum_and_copy_from_iter_full(to, copy, &csum, from))
2209 return -EFAULT;
2210 skb->csum = csum_block_add(skb->csum, csum, offset);
2211 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
2212 if (!copy_from_iter_full_nocache(to, copy, from))
2213 return -EFAULT;
2214 } else if (!copy_from_iter_full(to, copy, from))
2215 return -EFAULT;
2216
2217 return 0;
2218}
2219
2220static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
2221 struct iov_iter *from, int copy)
2222{
2223 int err, offset = skb->len;
2224
2225 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
2226 copy, offset);
2227 if (err)
2228 __skb_trim(skb, offset);
2229
2230 return err;
2231}
2232
2233static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
2234 struct sk_buff *skb,
2235 struct page *page,
2236 int off, int copy)
2237{
2238 int err;
2239
2240 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
2241 copy, skb->len);
2242 if (err)
2243 return err;
2244
2245 skb_len_add(skb, copy);
2246 sk_wmem_queued_add(sk, copy);
2247 sk_mem_charge(sk, copy);
2248 return 0;
2249}
2250
2251/**
2252 * sk_wmem_alloc_get - returns write allocations
2253 * @sk: socket
2254 *
2255 * Return: sk_wmem_alloc minus initial offset of one
2256 */
2257static inline int sk_wmem_alloc_get(const struct sock *sk)
2258{
2259 return refcount_read(&sk->sk_wmem_alloc) - 1;
2260}
2261
2262/**
2263 * sk_rmem_alloc_get - returns read allocations
2264 * @sk: socket
2265 *
2266 * Return: sk_rmem_alloc
2267 */
2268static inline int sk_rmem_alloc_get(const struct sock *sk)
2269{
2270 return atomic_read(&sk->sk_rmem_alloc);
2271}
2272
2273/**
2274 * sk_has_allocations - check if allocations are outstanding
2275 * @sk: socket
2276 *
2277 * Return: true if socket has write or read allocations
2278 */
2279static inline bool sk_has_allocations(const struct sock *sk)
2280{
2281 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
2282}
2283
2284/**
2285 * skwq_has_sleeper - check if there are any waiting processes
2286 * @wq: struct socket_wq
2287 *
2288 * Return: true if socket_wq has waiting processes
2289 *
2290 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory
2291 * barrier call. They were added due to the race found within the tcp code.
2292 *
2293 * Consider following tcp code paths::
2294 *
2295 * CPU1 CPU2
2296 * sys_select receive packet
2297 * ... ...
2298 * __add_wait_queue update tp->rcv_nxt
2299 * ... ...
2300 * tp->rcv_nxt check sock_def_readable
2301 * ... {
2302 * schedule rcu_read_lock();
2303 * wq = rcu_dereference(sk->sk_wq);
2304 * if (wq && waitqueue_active(&wq->wait))
2305 * wake_up_interruptible(&wq->wait)
2306 * ...
2307 * }
2308 *
2309 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
2310 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1
2311 * could then endup calling schedule and sleep forever if there are no more
2312 * data on the socket.
2313 *
2314 */
2315static inline bool skwq_has_sleeper(struct socket_wq *wq)
2316{
2317 return wq && wq_has_sleeper(&wq->wait);
2318}
2319
2320/**
2321 * sock_poll_wait - place memory barrier behind the poll_wait call.
2322 * @filp: file
2323 * @sock: socket to wait on
2324 * @p: poll_table
2325 *
2326 * See the comments in the wq_has_sleeper function.
2327 */
2328static inline void sock_poll_wait(struct file *filp, struct socket *sock,
2329 poll_table *p)
2330{
2331 if (!poll_does_not_wait(p)) {
2332 poll_wait(filp, &sock->wq.wait, p);
2333 /* We need to be sure we are in sync with the
2334 * socket flags modification.
2335 *
2336 * This memory barrier is paired in the wq_has_sleeper.
2337 */
2338 smp_mb();
2339 }
2340}
2341
2342static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk)
2343{
2344 /* This pairs with WRITE_ONCE() in sk_set_txhash() */
2345 u32 txhash = READ_ONCE(sk->sk_txhash);
2346
2347 if (txhash) {
2348 skb->l4_hash = 1;
2349 skb->hash = txhash;
2350 }
2351}
2352
2353void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);
2354
2355/*
2356 * Queue a received datagram if it will fit. Stream and sequenced
2357 * protocols can't normally use this as they need to fit buffers in
2358 * and play with them.
2359 *
2360 * Inlined as it's very short and called for pretty much every
2361 * packet ever received.
2362 */
2363static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
2364{
2365 skb_orphan(skb);
2366 skb->sk = sk;
2367 skb->destructor = sock_rfree;
2368 atomic_add(skb->truesize, &sk->sk_rmem_alloc);
2369 sk_mem_charge(sk, skb->truesize);
2370}
2371
2372static inline __must_check bool skb_set_owner_sk_safe(struct sk_buff *skb, struct sock *sk)
2373{
2374 if (sk && refcount_inc_not_zero(&sk->sk_refcnt)) {
2375 skb_orphan(skb);
2376 skb->destructor = sock_efree;
2377 skb->sk = sk;
2378 return true;
2379 }
2380 return false;
2381}
2382
2383static inline void skb_prepare_for_gro(struct sk_buff *skb)
2384{
2385 if (skb->destructor != sock_wfree) {
2386 skb_orphan(skb);
2387 return;
2388 }
2389 skb->slow_gro = 1;
2390}
2391
2392void sk_reset_timer(struct sock *sk, struct timer_list *timer,
2393 unsigned long expires);
2394
2395void sk_stop_timer(struct sock *sk, struct timer_list *timer);
2396
2397void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer);
2398
2399int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue,
2400 struct sk_buff *skb, unsigned int flags,
2401 void (*destructor)(struct sock *sk,
2402 struct sk_buff *skb));
2403int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2404
2405int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb,
2406 enum skb_drop_reason *reason);
2407
2408static inline int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
2409{
2410 return sock_queue_rcv_skb_reason(sk, skb, NULL);
2411}
2412
2413int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2414struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
2415
2416/*
2417 * Recover an error report and clear atomically
2418 */
2419
2420static inline int sock_error(struct sock *sk)
2421{
2422 int err;
2423
2424 /* Avoid an atomic operation for the common case.
2425 * This is racy since another cpu/thread can change sk_err under us.
2426 */
2427 if (likely(data_race(!sk->sk_err)))
2428 return 0;
2429
2430 err = xchg(&sk->sk_err, 0);
2431 return -err;
2432}
2433
2434void sk_error_report(struct sock *sk);
2435
2436static inline unsigned long sock_wspace(struct sock *sk)
2437{
2438 int amt = 0;
2439
2440 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2441 amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc);
2442 if (amt < 0)
2443 amt = 0;
2444 }
2445 return amt;
2446}
2447
2448/* Note:
2449 * We use sk->sk_wq_raw, from contexts knowing this
2450 * pointer is not NULL and cannot disappear/change.
2451 */
2452static inline void sk_set_bit(int nr, struct sock *sk)
2453{
2454 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2455 !sock_flag(sk, SOCK_FASYNC))
2456 return;
2457
2458 set_bit(nr, &sk->sk_wq_raw->flags);
2459}
2460
2461static inline void sk_clear_bit(int nr, struct sock *sk)
2462{
2463 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2464 !sock_flag(sk, SOCK_FASYNC))
2465 return;
2466
2467 clear_bit(nr, &sk->sk_wq_raw->flags);
2468}
2469
2470static inline void sk_wake_async(const struct sock *sk, int how, int band)
2471{
2472 if (sock_flag(sk, SOCK_FASYNC)) {
2473 rcu_read_lock();
2474 sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2475 rcu_read_unlock();
2476 }
2477}
2478
2479/* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2480 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2481 * Note: for send buffers, TCP works better if we can build two skbs at
2482 * minimum.
2483 */
2484#define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2485
2486#define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2)
2487#define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE
2488
2489static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2490{
2491 u32 val;
2492
2493 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)
2494 return;
2495
2496 val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2497 val = max_t(u32, val, sk_unused_reserved_mem(sk));
2498
2499 WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF));
2500}
2501
2502/**
2503 * sk_page_frag - return an appropriate page_frag
2504 * @sk: socket
2505 *
2506 * Use the per task page_frag instead of the per socket one for
2507 * optimization when we know that we're in process context and own
2508 * everything that's associated with %current.
2509 *
2510 * Both direct reclaim and page faults can nest inside other
2511 * socket operations and end up recursing into sk_page_frag()
2512 * while it's already in use: explicitly avoid task page_frag
2513 * usage if the caller is potentially doing any of them.
2514 * This assumes that page fault handlers use the GFP_NOFS flags.
2515 *
2516 * Return: a per task page_frag if context allows that,
2517 * otherwise a per socket one.
2518 */
2519static inline struct page_frag *sk_page_frag(struct sock *sk)
2520{
2521 if ((sk->sk_allocation & (__GFP_DIRECT_RECLAIM | __GFP_MEMALLOC | __GFP_FS)) ==
2522 (__GFP_DIRECT_RECLAIM | __GFP_FS))
2523 return &current->task_frag;
2524
2525 return &sk->sk_frag;
2526}
2527
2528bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2529
2530/*
2531 * Default write policy as shown to user space via poll/select/SIGIO
2532 */
2533static inline bool sock_writeable(const struct sock *sk)
2534{
2535 return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1);
2536}
2537
2538static inline gfp_t gfp_any(void)
2539{
2540 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2541}
2542
2543static inline gfp_t gfp_memcg_charge(void)
2544{
2545 return in_softirq() ? GFP_NOWAIT : GFP_KERNEL;
2546}
2547
2548static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2549{
2550 return noblock ? 0 : sk->sk_rcvtimeo;
2551}
2552
2553static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2554{
2555 return noblock ? 0 : sk->sk_sndtimeo;
2556}
2557
2558static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2559{
2560 int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len);
2561
2562 return v ?: 1;
2563}
2564
2565/* Alas, with timeout socket operations are not restartable.
2566 * Compare this to poll().
2567 */
2568static inline int sock_intr_errno(long timeo)
2569{
2570 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2571}
2572
2573struct sock_skb_cb {
2574 u32 dropcount;
2575};
2576
2577/* Store sock_skb_cb at the end of skb->cb[] so protocol families
2578 * using skb->cb[] would keep using it directly and utilize its
2579 * alignement guarantee.
2580 */
2581#define SOCK_SKB_CB_OFFSET ((sizeof_field(struct sk_buff, cb) - \
2582 sizeof(struct sock_skb_cb)))
2583
2584#define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
2585 SOCK_SKB_CB_OFFSET))
2586
2587#define sock_skb_cb_check_size(size) \
2588 BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
2589
2590static inline void
2591sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
2592{
2593 SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ?
2594 atomic_read(&sk->sk_drops) : 0;
2595}
2596
2597static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb)
2598{
2599 int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs);
2600
2601 atomic_add(segs, &sk->sk_drops);
2602}
2603
2604static inline ktime_t sock_read_timestamp(struct sock *sk)
2605{
2606#if BITS_PER_LONG==32
2607 unsigned int seq;
2608 ktime_t kt;
2609
2610 do {
2611 seq = read_seqbegin(&sk->sk_stamp_seq);
2612 kt = sk->sk_stamp;
2613 } while (read_seqretry(&sk->sk_stamp_seq, seq));
2614
2615 return kt;
2616#else
2617 return READ_ONCE(sk->sk_stamp);
2618#endif
2619}
2620
2621static inline void sock_write_timestamp(struct sock *sk, ktime_t kt)
2622{
2623#if BITS_PER_LONG==32
2624 write_seqlock(&sk->sk_stamp_seq);
2625 sk->sk_stamp = kt;
2626 write_sequnlock(&sk->sk_stamp_seq);
2627#else
2628 WRITE_ONCE(sk->sk_stamp, kt);
2629#endif
2630}
2631
2632void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2633 struct sk_buff *skb);
2634void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2635 struct sk_buff *skb);
2636
2637static inline void
2638sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2639{
2640 ktime_t kt = skb->tstamp;
2641 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2642
2643 /*
2644 * generate control messages if
2645 * - receive time stamping in software requested
2646 * - software time stamp available and wanted
2647 * - hardware time stamps available and wanted
2648 */
2649 if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2650 (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
2651 (kt && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
2652 (hwtstamps->hwtstamp &&
2653 (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
2654 __sock_recv_timestamp(msg, sk, skb);
2655 else
2656 sock_write_timestamp(sk, kt);
2657
2658 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid)
2659 __sock_recv_wifi_status(msg, sk, skb);
2660}
2661
2662void __sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
2663 struct sk_buff *skb);
2664
2665#define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC)
2666static inline void sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
2667 struct sk_buff *skb)
2668{
2669#define FLAGS_RECV_CMSGS ((1UL << SOCK_RXQ_OVFL) | \
2670 (1UL << SOCK_RCVTSTAMP) | \
2671 (1UL << SOCK_RCVMARK))
2672#define TSFLAGS_ANY (SOF_TIMESTAMPING_SOFTWARE | \
2673 SOF_TIMESTAMPING_RAW_HARDWARE)
2674
2675 if (sk->sk_flags & FLAGS_RECV_CMSGS || sk->sk_tsflags & TSFLAGS_ANY)
2676 __sock_recv_cmsgs(msg, sk, skb);
2677 else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP)))
2678 sock_write_timestamp(sk, skb->tstamp);
2679 else if (unlikely(sk->sk_stamp == SK_DEFAULT_STAMP))
2680 sock_write_timestamp(sk, 0);
2681}
2682
2683void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags);
2684
2685/**
2686 * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2687 * @sk: socket sending this packet
2688 * @tsflags: timestamping flags to use
2689 * @tx_flags: completed with instructions for time stamping
2690 * @tskey: filled in with next sk_tskey (not for TCP, which uses seqno)
2691 *
2692 * Note: callers should take care of initial ``*tx_flags`` value (usually 0)
2693 */
2694static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2695 __u8 *tx_flags, __u32 *tskey)
2696{
2697 if (unlikely(tsflags)) {
2698 __sock_tx_timestamp(tsflags, tx_flags);
2699 if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey &&
2700 tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK)
2701 *tskey = atomic_inc_return(&sk->sk_tskey) - 1;
2702 }
2703 if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
2704 *tx_flags |= SKBTX_WIFI_STATUS;
2705}
2706
2707static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2708 __u8 *tx_flags)
2709{
2710 _sock_tx_timestamp(sk, tsflags, tx_flags, NULL);
2711}
2712
2713static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags)
2714{
2715 _sock_tx_timestamp(skb->sk, tsflags, &skb_shinfo(skb)->tx_flags,
2716 &skb_shinfo(skb)->tskey);
2717}
2718
2719static inline bool sk_is_tcp(const struct sock *sk)
2720{
2721 return sk->sk_type == SOCK_STREAM && sk->sk_protocol == IPPROTO_TCP;
2722}
2723
2724/**
2725 * sk_eat_skb - Release a skb if it is no longer needed
2726 * @sk: socket to eat this skb from
2727 * @skb: socket buffer to eat
2728 *
2729 * This routine must be called with interrupts disabled or with the socket
2730 * locked so that the sk_buff queue operation is ok.
2731*/
2732static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
2733{
2734 __skb_unlink(skb, &sk->sk_receive_queue);
2735 __kfree_skb(skb);
2736}
2737
2738static inline bool
2739skb_sk_is_prefetched(struct sk_buff *skb)
2740{
2741#ifdef CONFIG_INET
2742 return skb->destructor == sock_pfree;
2743#else
2744 return false;
2745#endif /* CONFIG_INET */
2746}
2747
2748/* This helper checks if a socket is a full socket,
2749 * ie _not_ a timewait or request socket.
2750 */
2751static inline bool sk_fullsock(const struct sock *sk)
2752{
2753 return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
2754}
2755
2756static inline bool
2757sk_is_refcounted(struct sock *sk)
2758{
2759 /* Only full sockets have sk->sk_flags. */
2760 return !sk_fullsock(sk) || !sock_flag(sk, SOCK_RCU_FREE);
2761}
2762
2763/**
2764 * skb_steal_sock - steal a socket from an sk_buff
2765 * @skb: sk_buff to steal the socket from
2766 * @refcounted: is set to true if the socket is reference-counted
2767 */
2768static inline struct sock *
2769skb_steal_sock(struct sk_buff *skb, bool *refcounted)
2770{
2771 if (skb->sk) {
2772 struct sock *sk = skb->sk;
2773
2774 *refcounted = true;
2775 if (skb_sk_is_prefetched(skb))
2776 *refcounted = sk_is_refcounted(sk);
2777 skb->destructor = NULL;
2778 skb->sk = NULL;
2779 return sk;
2780 }
2781 *refcounted = false;
2782 return NULL;
2783}
2784
2785/* Checks if this SKB belongs to an HW offloaded socket
2786 * and whether any SW fallbacks are required based on dev.
2787 * Check decrypted mark in case skb_orphan() cleared socket.
2788 */
2789static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb,
2790 struct net_device *dev)
2791{
2792#ifdef CONFIG_SOCK_VALIDATE_XMIT
2793 struct sock *sk = skb->sk;
2794
2795 if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) {
2796 skb = sk->sk_validate_xmit_skb(sk, dev, skb);
2797#ifdef CONFIG_TLS_DEVICE
2798 } else if (unlikely(skb->decrypted)) {
2799 pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n");
2800 kfree_skb(skb);
2801 skb = NULL;
2802#endif
2803 }
2804#endif
2805
2806 return skb;
2807}
2808
2809/* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
2810 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
2811 */
2812static inline bool sk_listener(const struct sock *sk)
2813{
2814 return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
2815}
2816
2817void sock_enable_timestamp(struct sock *sk, enum sock_flags flag);
2818int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
2819 int type);
2820
2821bool sk_ns_capable(const struct sock *sk,
2822 struct user_namespace *user_ns, int cap);
2823bool sk_capable(const struct sock *sk, int cap);
2824bool sk_net_capable(const struct sock *sk, int cap);
2825
2826void sk_get_meminfo(const struct sock *sk, u32 *meminfo);
2827
2828/* Take into consideration the size of the struct sk_buff overhead in the
2829 * determination of these values, since that is non-constant across
2830 * platforms. This makes socket queueing behavior and performance
2831 * not depend upon such differences.
2832 */
2833#define _SK_MEM_PACKETS 256
2834#define _SK_MEM_OVERHEAD SKB_TRUESIZE(256)
2835#define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2836#define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2837
2838extern __u32 sysctl_wmem_max;
2839extern __u32 sysctl_rmem_max;
2840
2841extern int sysctl_tstamp_allow_data;
2842extern int sysctl_optmem_max;
2843
2844extern __u32 sysctl_wmem_default;
2845extern __u32 sysctl_rmem_default;
2846
2847#define SKB_FRAG_PAGE_ORDER get_order(32768)
2848DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2849
2850static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto)
2851{
2852 /* Does this proto have per netns sysctl_wmem ? */
2853 if (proto->sysctl_wmem_offset)
2854 return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset));
2855
2856 return READ_ONCE(*proto->sysctl_wmem);
2857}
2858
2859static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto)
2860{
2861 /* Does this proto have per netns sysctl_rmem ? */
2862 if (proto->sysctl_rmem_offset)
2863 return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset));
2864
2865 return READ_ONCE(*proto->sysctl_rmem);
2866}
2867
2868/* Default TCP Small queue budget is ~1 ms of data (1sec >> 10)
2869 * Some wifi drivers need to tweak it to get more chunks.
2870 * They can use this helper from their ndo_start_xmit()
2871 */
2872static inline void sk_pacing_shift_update(struct sock *sk, int val)
2873{
2874 if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val)
2875 return;
2876 WRITE_ONCE(sk->sk_pacing_shift, val);
2877}
2878
2879/* if a socket is bound to a device, check that the given device
2880 * index is either the same or that the socket is bound to an L3
2881 * master device and the given device index is also enslaved to
2882 * that L3 master
2883 */
2884static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif)
2885{
2886 int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
2887 int mdif;
2888
2889 if (!bound_dev_if || bound_dev_if == dif)
2890 return true;
2891
2892 mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif);
2893 if (mdif && mdif == bound_dev_if)
2894 return true;
2895
2896 return false;
2897}
2898
2899void sock_def_readable(struct sock *sk);
2900
2901int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk);
2902void sock_set_timestamp(struct sock *sk, int optname, bool valbool);
2903int sock_set_timestamping(struct sock *sk, int optname,
2904 struct so_timestamping timestamping);
2905
2906void sock_enable_timestamps(struct sock *sk);
2907void sock_no_linger(struct sock *sk);
2908void sock_set_keepalive(struct sock *sk);
2909void sock_set_priority(struct sock *sk, u32 priority);
2910void sock_set_rcvbuf(struct sock *sk, int val);
2911void sock_set_mark(struct sock *sk, u32 val);
2912void sock_set_reuseaddr(struct sock *sk);
2913void sock_set_reuseport(struct sock *sk);
2914void sock_set_sndtimeo(struct sock *sk, s64 secs);
2915
2916int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len);
2917
2918int sock_get_timeout(long timeo, void *optval, bool old_timeval);
2919int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
2920 sockptr_t optval, int optlen, bool old_timeval);
2921
2922static inline bool sk_is_readable(struct sock *sk)
2923{
2924 if (sk->sk_prot->sock_is_readable)
2925 return sk->sk_prot->sock_is_readable(sk);
2926 return false;
2927}
2928#endif /* _SOCK_H */
2929

source code of linux/include/net/sock.h