1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
6 *
7 * Definitions for the AF_INET socket handler.
8 *
9 * Version: @(#)sock.h 1.0.4 05/13/93
10 *
11 * Authors: Ross Biro
12 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
13 * Corey Minyard <wf-rch!minyard@relay.EU.net>
14 * Florian La Roche <flla@stud.uni-sb.de>
15 *
16 * Fixes:
17 * Alan Cox : Volatiles in skbuff pointers. See
18 * skbuff comments. May be overdone,
19 * better to prove they can be removed
20 * than the reverse.
21 * Alan Cox : Added a zapped field for tcp to note
22 * a socket is reset and must stay shut up
23 * Alan Cox : New fields for options
24 * Pauline Middelink : identd support
25 * Alan Cox : Eliminate low level recv/recvfrom
26 * David S. Miller : New socket lookup architecture.
27 * Steve Whitehouse: Default routines for sock_ops
28 * Arnaldo C. Melo : removed net_pinfo, tp_pinfo and made
29 * protinfo be just a void pointer, as the
30 * protocol specific parts were moved to
31 * respective headers and ipv4/v6, etc now
32 * use private slabcaches for its socks
33 * Pedro Hortas : New flags field for socket options
34 */
35#ifndef _SOCK_H
36#define _SOCK_H
37
38#include <linux/hardirq.h>
39#include <linux/kernel.h>
40#include <linux/list.h>
41#include <linux/list_nulls.h>
42#include <linux/timer.h>
43#include <linux/cache.h>
44#include <linux/bitops.h>
45#include <linux/lockdep.h>
46#include <linux/netdevice.h>
47#include <linux/skbuff.h> /* struct sk_buff */
48#include <linux/mm.h>
49#include <linux/security.h>
50#include <linux/slab.h>
51#include <linux/uaccess.h>
52#include <linux/page_counter.h>
53#include <linux/memcontrol.h>
54#include <linux/static_key.h>
55#include <linux/sched.h>
56#include <linux/wait.h>
57#include <linux/cgroup-defs.h>
58#include <linux/rbtree.h>
59#include <linux/rculist_nulls.h>
60#include <linux/poll.h>
61#include <linux/sockptr.h>
62#include <linux/indirect_call_wrapper.h>
63#include <linux/atomic.h>
64#include <linux/refcount.h>
65#include <linux/llist.h>
66#include <net/dst.h>
67#include <net/checksum.h>
68#include <net/tcp_states.h>
69#include <linux/net_tstamp.h>
70#include <net/l3mdev.h>
71#include <uapi/linux/socket.h>
72
73/*
74 * This structure really needs to be cleaned up.
75 * Most of it is for TCP, and not used by any of
76 * the other protocols.
77 */
78
79/* This is the per-socket lock. The spinlock provides a synchronization
80 * between user contexts and software interrupt processing, whereas the
81 * mini-semaphore synchronizes multiple users amongst themselves.
82 */
83typedef struct {
84 spinlock_t slock;
85 int owned;
86 wait_queue_head_t wq;
87 /*
88 * We express the mutex-alike socket_lock semantics
89 * to the lock validator by explicitly managing
90 * the slock as a lock variant (in addition to
91 * the slock itself):
92 */
93#ifdef CONFIG_DEBUG_LOCK_ALLOC
94 struct lockdep_map dep_map;
95#endif
96} socket_lock_t;
97
98struct sock;
99struct proto;
100struct net;
101
102typedef __u32 __bitwise __portpair;
103typedef __u64 __bitwise __addrpair;
104
105/**
106 * struct sock_common - minimal network layer representation of sockets
107 * @skc_daddr: Foreign IPv4 addr
108 * @skc_rcv_saddr: Bound local IPv4 addr
109 * @skc_addrpair: 8-byte-aligned __u64 union of @skc_daddr & @skc_rcv_saddr
110 * @skc_hash: hash value used with various protocol lookup tables
111 * @skc_u16hashes: two u16 hash values used by UDP lookup tables
112 * @skc_dport: placeholder for inet_dport/tw_dport
113 * @skc_num: placeholder for inet_num/tw_num
114 * @skc_portpair: __u32 union of @skc_dport & @skc_num
115 * @skc_family: network address family
116 * @skc_state: Connection state
117 * @skc_reuse: %SO_REUSEADDR setting
118 * @skc_reuseport: %SO_REUSEPORT setting
119 * @skc_ipv6only: socket is IPV6 only
120 * @skc_net_refcnt: socket is using net ref counting
121 * @skc_bound_dev_if: bound device index if != 0
122 * @skc_bind_node: bind hash linkage for various protocol lookup tables
123 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
124 * @skc_prot: protocol handlers inside a network family
125 * @skc_net: reference to the network namespace of this socket
126 * @skc_v6_daddr: IPV6 destination address
127 * @skc_v6_rcv_saddr: IPV6 source address
128 * @skc_cookie: socket's cookie value
129 * @skc_node: main hash linkage for various protocol lookup tables
130 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
131 * @skc_tx_queue_mapping: tx queue number for this connection
132 * @skc_rx_queue_mapping: rx queue number for this connection
133 * @skc_flags: place holder for sk_flags
134 * %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
135 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings
136 * @skc_listener: connection request listener socket (aka rsk_listener)
137 * [union with @skc_flags]
138 * @skc_tw_dr: (aka tw_dr) ptr to &struct inet_timewait_death_row
139 * [union with @skc_flags]
140 * @skc_incoming_cpu: record/match cpu processing incoming packets
141 * @skc_rcv_wnd: (aka rsk_rcv_wnd) TCP receive window size (possibly scaled)
142 * [union with @skc_incoming_cpu]
143 * @skc_tw_rcv_nxt: (aka tw_rcv_nxt) TCP window next expected seq number
144 * [union with @skc_incoming_cpu]
145 * @skc_refcnt: reference count
146 *
147 * This is the minimal network layer representation of sockets, the header
148 * for struct sock and struct inet_timewait_sock.
149 */
150struct sock_common {
151 union {
152 __addrpair skc_addrpair;
153 struct {
154 __be32 skc_daddr;
155 __be32 skc_rcv_saddr;
156 };
157 };
158 union {
159 unsigned int skc_hash;
160 __u16 skc_u16hashes[2];
161 };
162 /* skc_dport && skc_num must be grouped as well */
163 union {
164 __portpair skc_portpair;
165 struct {
166 __be16 skc_dport;
167 __u16 skc_num;
168 };
169 };
170
171 unsigned short skc_family;
172 volatile unsigned char skc_state;
173 unsigned char skc_reuse:4;
174 unsigned char skc_reuseport:1;
175 unsigned char skc_ipv6only:1;
176 unsigned char skc_net_refcnt:1;
177 int skc_bound_dev_if;
178 union {
179 struct hlist_node skc_bind_node;
180 struct hlist_node skc_portaddr_node;
181 };
182 struct proto *skc_prot;
183 possible_net_t skc_net;
184
185#if IS_ENABLED(CONFIG_IPV6)
186 struct in6_addr skc_v6_daddr;
187 struct in6_addr skc_v6_rcv_saddr;
188#endif
189
190 atomic64_t skc_cookie;
191
192 /* following fields are padding to force
193 * offset(struct sock, sk_refcnt) == 128 on 64bit arches
194 * assuming IPV6 is enabled. We use this padding differently
195 * for different kind of 'sockets'
196 */
197 union {
198 unsigned long skc_flags;
199 struct sock *skc_listener; /* request_sock */
200 struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */
201 };
202 /*
203 * fields between dontcopy_begin/dontcopy_end
204 * are not copied in sock_copy()
205 */
206 /* private: */
207 int skc_dontcopy_begin[0];
208 /* public: */
209 union {
210 struct hlist_node skc_node;
211 struct hlist_nulls_node skc_nulls_node;
212 };
213 unsigned short skc_tx_queue_mapping;
214#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
215 unsigned short skc_rx_queue_mapping;
216#endif
217 union {
218 int skc_incoming_cpu;
219 u32 skc_rcv_wnd;
220 u32 skc_tw_rcv_nxt; /* struct tcp_timewait_sock */
221 };
222
223 refcount_t skc_refcnt;
224 /* private: */
225 int skc_dontcopy_end[0];
226 union {
227 u32 skc_rxhash;
228 u32 skc_window_clamp;
229 u32 skc_tw_snd_nxt; /* struct tcp_timewait_sock */
230 };
231 /* public: */
232};
233
234struct bpf_local_storage;
235struct sk_filter;
236
237/**
238 * struct sock - network layer representation of sockets
239 * @__sk_common: shared layout with inet_timewait_sock
240 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
241 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
242 * @sk_lock: synchronizer
243 * @sk_kern_sock: True if sock is using kernel lock classes
244 * @sk_rcvbuf: size of receive buffer in bytes
245 * @sk_wq: sock wait queue and async head
246 * @sk_rx_dst: receive input route used by early demux
247 * @sk_rx_dst_ifindex: ifindex for @sk_rx_dst
248 * @sk_rx_dst_cookie: cookie for @sk_rx_dst
249 * @sk_dst_cache: destination cache
250 * @sk_dst_pending_confirm: need to confirm neighbour
251 * @sk_policy: flow policy
252 * @sk_receive_queue: incoming packets
253 * @sk_wmem_alloc: transmit queue bytes committed
254 * @sk_tsq_flags: TCP Small Queues flags
255 * @sk_write_queue: Packet sending queue
256 * @sk_omem_alloc: "o" is "option" or "other"
257 * @sk_wmem_queued: persistent queue size
258 * @sk_forward_alloc: space allocated forward
259 * @sk_reserved_mem: space reserved and non-reclaimable for the socket
260 * @sk_napi_id: id of the last napi context to receive data for sk
261 * @sk_ll_usec: usecs to busypoll when there is no data
262 * @sk_allocation: allocation mode
263 * @sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler)
264 * @sk_pacing_status: Pacing status (requested, handled by sch_fq)
265 * @sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE)
266 * @sk_sndbuf: size of send buffer in bytes
267 * @sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets
268 * @sk_no_check_rx: allow zero checksum in RX packets
269 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
270 * @sk_gso_disabled: if set, NETIF_F_GSO_MASK is forbidden.
271 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
272 * @sk_gso_max_size: Maximum GSO segment size to build
273 * @sk_gso_max_segs: Maximum number of GSO segments
274 * @sk_pacing_shift: scaling factor for TCP Small Queues
275 * @sk_lingertime: %SO_LINGER l_linger setting
276 * @sk_backlog: always used with the per-socket spinlock held
277 * @sk_callback_lock: used with the callbacks in the end of this struct
278 * @sk_error_queue: rarely used
279 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
280 * IPV6_ADDRFORM for instance)
281 * @sk_err: last error
282 * @sk_err_soft: errors that don't cause failure but are the cause of a
283 * persistent failure not just 'timed out'
284 * @sk_drops: raw/udp drops counter
285 * @sk_ack_backlog: current listen backlog
286 * @sk_max_ack_backlog: listen backlog set in listen()
287 * @sk_uid: user id of owner
288 * @sk_prefer_busy_poll: prefer busypolling over softirq processing
289 * @sk_busy_poll_budget: napi processing budget when busypolling
290 * @sk_priority: %SO_PRIORITY setting
291 * @sk_type: socket type (%SOCK_STREAM, etc)
292 * @sk_protocol: which protocol this socket belongs in this network family
293 * @sk_peer_lock: lock protecting @sk_peer_pid and @sk_peer_cred
294 * @sk_peer_pid: &struct pid for this socket's peer
295 * @sk_peer_cred: %SO_PEERCRED setting
296 * @sk_rcvlowat: %SO_RCVLOWAT setting
297 * @sk_rcvtimeo: %SO_RCVTIMEO setting
298 * @sk_sndtimeo: %SO_SNDTIMEO setting
299 * @sk_txhash: computed flow hash for use on transmit
300 * @sk_txrehash: enable TX hash rethink
301 * @sk_filter: socket filtering instructions
302 * @sk_timer: sock cleanup timer
303 * @sk_stamp: time stamp of last packet received
304 * @sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only
305 * @sk_tsflags: SO_TIMESTAMPING flags
306 * @sk_use_task_frag: allow sk_page_frag() to use current->task_frag.
307 * Sockets that can be used under memory reclaim should
308 * set this to false.
309 * @sk_bind_phc: SO_TIMESTAMPING bind PHC index of PTP virtual clock
310 * for timestamping
311 * @sk_tskey: counter to disambiguate concurrent tstamp requests
312 * @sk_zckey: counter to order MSG_ZEROCOPY notifications
313 * @sk_socket: Identd and reporting IO signals
314 * @sk_user_data: RPC layer private data. Write-protected by @sk_callback_lock.
315 * @sk_frag: cached page frag
316 * @sk_peek_off: current peek_offset value
317 * @sk_send_head: front of stuff to transmit
318 * @tcp_rtx_queue: TCP re-transmit queue [union with @sk_send_head]
319 * @sk_security: used by security modules
320 * @sk_mark: generic packet mark
321 * @sk_cgrp_data: cgroup data for this cgroup
322 * @sk_memcg: this socket's memory cgroup association
323 * @sk_write_pending: a write to stream socket waits to start
324 * @sk_disconnects: number of disconnect operations performed on this sock
325 * @sk_state_change: callback to indicate change in the state of the sock
326 * @sk_data_ready: callback to indicate there is data to be processed
327 * @sk_write_space: callback to indicate there is bf sending space available
328 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
329 * @sk_backlog_rcv: callback to process the backlog
330 * @sk_validate_xmit_skb: ptr to an optional validate function
331 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
332 * @sk_reuseport_cb: reuseport group container
333 * @sk_bpf_storage: ptr to cache and control for bpf_sk_storage
334 * @sk_rcu: used during RCU grace period
335 * @sk_clockid: clockid used by time-based scheduling (SO_TXTIME)
336 * @sk_txtime_deadline_mode: set deadline mode for SO_TXTIME
337 * @sk_txtime_report_errors: set report errors mode for SO_TXTIME
338 * @sk_txtime_unused: unused txtime flags
339 * @ns_tracker: tracker for netns reference
340 */
341struct sock {
342 /*
343 * Now struct inet_timewait_sock also uses sock_common, so please just
344 * don't add nothing before this first member (__sk_common) --acme
345 */
346 struct sock_common __sk_common;
347#define sk_node __sk_common.skc_node
348#define sk_nulls_node __sk_common.skc_nulls_node
349#define sk_refcnt __sk_common.skc_refcnt
350#define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping
351#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
352#define sk_rx_queue_mapping __sk_common.skc_rx_queue_mapping
353#endif
354
355#define sk_dontcopy_begin __sk_common.skc_dontcopy_begin
356#define sk_dontcopy_end __sk_common.skc_dontcopy_end
357#define sk_hash __sk_common.skc_hash
358#define sk_portpair __sk_common.skc_portpair
359#define sk_num __sk_common.skc_num
360#define sk_dport __sk_common.skc_dport
361#define sk_addrpair __sk_common.skc_addrpair
362#define sk_daddr __sk_common.skc_daddr
363#define sk_rcv_saddr __sk_common.skc_rcv_saddr
364#define sk_family __sk_common.skc_family
365#define sk_state __sk_common.skc_state
366#define sk_reuse __sk_common.skc_reuse
367#define sk_reuseport __sk_common.skc_reuseport
368#define sk_ipv6only __sk_common.skc_ipv6only
369#define sk_net_refcnt __sk_common.skc_net_refcnt
370#define sk_bound_dev_if __sk_common.skc_bound_dev_if
371#define sk_bind_node __sk_common.skc_bind_node
372#define sk_prot __sk_common.skc_prot
373#define sk_net __sk_common.skc_net
374#define sk_v6_daddr __sk_common.skc_v6_daddr
375#define sk_v6_rcv_saddr __sk_common.skc_v6_rcv_saddr
376#define sk_cookie __sk_common.skc_cookie
377#define sk_incoming_cpu __sk_common.skc_incoming_cpu
378#define sk_flags __sk_common.skc_flags
379#define sk_rxhash __sk_common.skc_rxhash
380
381 __cacheline_group_begin(sock_write_rx);
382
383 atomic_t sk_drops;
384 __s32 sk_peek_off;
385 struct sk_buff_head sk_error_queue;
386 struct sk_buff_head sk_receive_queue;
387 /*
388 * The backlog queue is special, it is always used with
389 * the per-socket spinlock held and requires low latency
390 * access. Therefore we special case it's implementation.
391 * Note : rmem_alloc is in this structure to fill a hole
392 * on 64bit arches, not because its logically part of
393 * backlog.
394 */
395 struct {
396 atomic_t rmem_alloc;
397 int len;
398 struct sk_buff *head;
399 struct sk_buff *tail;
400 } sk_backlog;
401#define sk_rmem_alloc sk_backlog.rmem_alloc
402
403 __cacheline_group_end(sock_write_rx);
404
405 __cacheline_group_begin(sock_read_rx);
406 /* early demux fields */
407 struct dst_entry __rcu *sk_rx_dst;
408 int sk_rx_dst_ifindex;
409 u32 sk_rx_dst_cookie;
410
411#ifdef CONFIG_NET_RX_BUSY_POLL
412 unsigned int sk_ll_usec;
413 unsigned int sk_napi_id;
414 u16 sk_busy_poll_budget;
415 u8 sk_prefer_busy_poll;
416#endif
417 u8 sk_userlocks;
418 int sk_rcvbuf;
419
420 struct sk_filter __rcu *sk_filter;
421 union {
422 struct socket_wq __rcu *sk_wq;
423 /* private: */
424 struct socket_wq *sk_wq_raw;
425 /* public: */
426 };
427
428 void (*sk_data_ready)(struct sock *sk);
429 long sk_rcvtimeo;
430 int sk_rcvlowat;
431 __cacheline_group_end(sock_read_rx);
432
433 __cacheline_group_begin(sock_read_rxtx);
434 int sk_err;
435 struct socket *sk_socket;
436 struct mem_cgroup *sk_memcg;
437#ifdef CONFIG_XFRM
438 struct xfrm_policy __rcu *sk_policy[2];
439#endif
440 __cacheline_group_end(sock_read_rxtx);
441
442 __cacheline_group_begin(sock_write_rxtx);
443 socket_lock_t sk_lock;
444 u32 sk_reserved_mem;
445 int sk_forward_alloc;
446 u32 sk_tsflags;
447 __cacheline_group_end(sock_write_rxtx);
448
449 __cacheline_group_begin(sock_write_tx);
450 int sk_write_pending;
451 atomic_t sk_omem_alloc;
452 int sk_sndbuf;
453
454 int sk_wmem_queued;
455 refcount_t sk_wmem_alloc;
456 unsigned long sk_tsq_flags;
457 union {
458 struct sk_buff *sk_send_head;
459 struct rb_root tcp_rtx_queue;
460 };
461 struct sk_buff_head sk_write_queue;
462 u32 sk_dst_pending_confirm;
463 u32 sk_pacing_status; /* see enum sk_pacing */
464 struct page_frag sk_frag;
465 struct timer_list sk_timer;
466
467 unsigned long sk_pacing_rate; /* bytes per second */
468 atomic_t sk_zckey;
469 atomic_t sk_tskey;
470 __cacheline_group_end(sock_write_tx);
471
472 __cacheline_group_begin(sock_read_tx);
473 unsigned long sk_max_pacing_rate;
474 long sk_sndtimeo;
475 u32 sk_priority;
476 u32 sk_mark;
477 struct dst_entry __rcu *sk_dst_cache;
478 netdev_features_t sk_route_caps;
479#ifdef CONFIG_SOCK_VALIDATE_XMIT
480 struct sk_buff* (*sk_validate_xmit_skb)(struct sock *sk,
481 struct net_device *dev,
482 struct sk_buff *skb);
483#endif
484 u16 sk_gso_type;
485 u16 sk_gso_max_segs;
486 unsigned int sk_gso_max_size;
487 gfp_t sk_allocation;
488 u32 sk_txhash;
489 u8 sk_pacing_shift;
490 bool sk_use_task_frag;
491 __cacheline_group_end(sock_read_tx);
492
493 /*
494 * Because of non atomicity rules, all
495 * changes are protected by socket lock.
496 */
497 u8 sk_gso_disabled : 1,
498 sk_kern_sock : 1,
499 sk_no_check_tx : 1,
500 sk_no_check_rx : 1;
501 u8 sk_shutdown;
502 u16 sk_type;
503 u16 sk_protocol;
504 unsigned long sk_lingertime;
505 struct proto *sk_prot_creator;
506 rwlock_t sk_callback_lock;
507 int sk_err_soft;
508 u32 sk_ack_backlog;
509 u32 sk_max_ack_backlog;
510 kuid_t sk_uid;
511 spinlock_t sk_peer_lock;
512 int sk_bind_phc;
513 struct pid *sk_peer_pid;
514 const struct cred *sk_peer_cred;
515
516 ktime_t sk_stamp;
517#if BITS_PER_LONG==32
518 seqlock_t sk_stamp_seq;
519#endif
520 int sk_disconnects;
521
522 u8 sk_txrehash;
523 u8 sk_clockid;
524 u8 sk_txtime_deadline_mode : 1,
525 sk_txtime_report_errors : 1,
526 sk_txtime_unused : 6;
527
528 void *sk_user_data;
529#ifdef CONFIG_SECURITY
530 void *sk_security;
531#endif
532 struct sock_cgroup_data sk_cgrp_data;
533 void (*sk_state_change)(struct sock *sk);
534 void (*sk_write_space)(struct sock *sk);
535 void (*sk_error_report)(struct sock *sk);
536 int (*sk_backlog_rcv)(struct sock *sk,
537 struct sk_buff *skb);
538 void (*sk_destruct)(struct sock *sk);
539 struct sock_reuseport __rcu *sk_reuseport_cb;
540#ifdef CONFIG_BPF_SYSCALL
541 struct bpf_local_storage __rcu *sk_bpf_storage;
542#endif
543 struct rcu_head sk_rcu;
544 netns_tracker ns_tracker;
545};
546
547enum sk_pacing {
548 SK_PACING_NONE = 0,
549 SK_PACING_NEEDED = 1,
550 SK_PACING_FQ = 2,
551};
552
553/* flag bits in sk_user_data
554 *
555 * - SK_USER_DATA_NOCOPY: Pointer stored in sk_user_data might
556 * not be suitable for copying when cloning the socket. For instance,
557 * it can point to a reference counted object. sk_user_data bottom
558 * bit is set if pointer must not be copied.
559 *
560 * - SK_USER_DATA_BPF: Mark whether sk_user_data field is
561 * managed/owned by a BPF reuseport array. This bit should be set
562 * when sk_user_data's sk is added to the bpf's reuseport_array.
563 *
564 * - SK_USER_DATA_PSOCK: Mark whether pointer stored in
565 * sk_user_data points to psock type. This bit should be set
566 * when sk_user_data is assigned to a psock object.
567 */
568#define SK_USER_DATA_NOCOPY 1UL
569#define SK_USER_DATA_BPF 2UL
570#define SK_USER_DATA_PSOCK 4UL
571#define SK_USER_DATA_PTRMASK ~(SK_USER_DATA_NOCOPY | SK_USER_DATA_BPF |\
572 SK_USER_DATA_PSOCK)
573
574/**
575 * sk_user_data_is_nocopy - Test if sk_user_data pointer must not be copied
576 * @sk: socket
577 */
578static inline bool sk_user_data_is_nocopy(const struct sock *sk)
579{
580 return ((uintptr_t)sk->sk_user_data & SK_USER_DATA_NOCOPY);
581}
582
583#define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
584
585/**
586 * __locked_read_sk_user_data_with_flags - return the pointer
587 * only if argument flags all has been set in sk_user_data. Otherwise
588 * return NULL
589 *
590 * @sk: socket
591 * @flags: flag bits
592 *
593 * The caller must be holding sk->sk_callback_lock.
594 */
595static inline void *
596__locked_read_sk_user_data_with_flags(const struct sock *sk,
597 uintptr_t flags)
598{
599 uintptr_t sk_user_data =
600 (uintptr_t)rcu_dereference_check(__sk_user_data(sk),
601 lockdep_is_held(&sk->sk_callback_lock));
602
603 WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK);
604
605 if ((sk_user_data & flags) == flags)
606 return (void *)(sk_user_data & SK_USER_DATA_PTRMASK);
607 return NULL;
608}
609
610/**
611 * __rcu_dereference_sk_user_data_with_flags - return the pointer
612 * only if argument flags all has been set in sk_user_data. Otherwise
613 * return NULL
614 *
615 * @sk: socket
616 * @flags: flag bits
617 */
618static inline void *
619__rcu_dereference_sk_user_data_with_flags(const struct sock *sk,
620 uintptr_t flags)
621{
622 uintptr_t sk_user_data = (uintptr_t)rcu_dereference(__sk_user_data(sk));
623
624 WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK);
625
626 if ((sk_user_data & flags) == flags)
627 return (void *)(sk_user_data & SK_USER_DATA_PTRMASK);
628 return NULL;
629}
630
631#define rcu_dereference_sk_user_data(sk) \
632 __rcu_dereference_sk_user_data_with_flags(sk, 0)
633#define __rcu_assign_sk_user_data_with_flags(sk, ptr, flags) \
634({ \
635 uintptr_t __tmp1 = (uintptr_t)(ptr), \
636 __tmp2 = (uintptr_t)(flags); \
637 WARN_ON_ONCE(__tmp1 & ~SK_USER_DATA_PTRMASK); \
638 WARN_ON_ONCE(__tmp2 & SK_USER_DATA_PTRMASK); \
639 rcu_assign_pointer(__sk_user_data((sk)), \
640 __tmp1 | __tmp2); \
641})
642#define rcu_assign_sk_user_data(sk, ptr) \
643 __rcu_assign_sk_user_data_with_flags(sk, ptr, 0)
644
645static inline
646struct net *sock_net(const struct sock *sk)
647{
648 return read_pnet(pnet: &sk->sk_net);
649}
650
651static inline
652void sock_net_set(struct sock *sk, struct net *net)
653{
654 write_pnet(pnet: &sk->sk_net, net);
655}
656
657/*
658 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
659 * or not whether his port will be reused by someone else. SK_FORCE_REUSE
660 * on a socket means that the socket will reuse everybody else's port
661 * without looking at the other's sk_reuse value.
662 */
663
664#define SK_NO_REUSE 0
665#define SK_CAN_REUSE 1
666#define SK_FORCE_REUSE 2
667
668int sk_set_peek_off(struct sock *sk, int val);
669
670static inline int sk_peek_offset(const struct sock *sk, int flags)
671{
672 if (unlikely(flags & MSG_PEEK)) {
673 return READ_ONCE(sk->sk_peek_off);
674 }
675
676 return 0;
677}
678
679static inline void sk_peek_offset_bwd(struct sock *sk, int val)
680{
681 s32 off = READ_ONCE(sk->sk_peek_off);
682
683 if (unlikely(off >= 0)) {
684 off = max_t(s32, off - val, 0);
685 WRITE_ONCE(sk->sk_peek_off, off);
686 }
687}
688
689static inline void sk_peek_offset_fwd(struct sock *sk, int val)
690{
691 sk_peek_offset_bwd(sk, val: -val);
692}
693
694/*
695 * Hashed lists helper routines
696 */
697static inline struct sock *sk_entry(const struct hlist_node *node)
698{
699 return hlist_entry(node, struct sock, sk_node);
700}
701
702static inline struct sock *__sk_head(const struct hlist_head *head)
703{
704 return hlist_entry(head->first, struct sock, sk_node);
705}
706
707static inline struct sock *sk_head(const struct hlist_head *head)
708{
709 return hlist_empty(h: head) ? NULL : __sk_head(head);
710}
711
712static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
713{
714 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
715}
716
717static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
718{
719 return hlist_nulls_empty(h: head) ? NULL : __sk_nulls_head(head);
720}
721
722static inline struct sock *sk_next(const struct sock *sk)
723{
724 return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node);
725}
726
727static inline struct sock *sk_nulls_next(const struct sock *sk)
728{
729 return (!is_a_nulls(ptr: sk->sk_nulls_node.next)) ?
730 hlist_nulls_entry(sk->sk_nulls_node.next,
731 struct sock, sk_nulls_node) :
732 NULL;
733}
734
735static inline bool sk_unhashed(const struct sock *sk)
736{
737 return hlist_unhashed(h: &sk->sk_node);
738}
739
740static inline bool sk_hashed(const struct sock *sk)
741{
742 return !sk_unhashed(sk);
743}
744
745static inline void sk_node_init(struct hlist_node *node)
746{
747 node->pprev = NULL;
748}
749
750static inline void __sk_del_node(struct sock *sk)
751{
752 __hlist_del(n: &sk->sk_node);
753}
754
755/* NB: equivalent to hlist_del_init_rcu */
756static inline bool __sk_del_node_init(struct sock *sk)
757{
758 if (sk_hashed(sk)) {
759 __sk_del_node(sk);
760 sk_node_init(node: &sk->sk_node);
761 return true;
762 }
763 return false;
764}
765
766/* Grab socket reference count. This operation is valid only
767 when sk is ALREADY grabbed f.e. it is found in hash table
768 or a list and the lookup is made under lock preventing hash table
769 modifications.
770 */
771
772static __always_inline void sock_hold(struct sock *sk)
773{
774 refcount_inc(r: &sk->sk_refcnt);
775}
776
777/* Ungrab socket in the context, which assumes that socket refcnt
778 cannot hit zero, f.e. it is true in context of any socketcall.
779 */
780static __always_inline void __sock_put(struct sock *sk)
781{
782 refcount_dec(r: &sk->sk_refcnt);
783}
784
785static inline bool sk_del_node_init(struct sock *sk)
786{
787 bool rc = __sk_del_node_init(sk);
788
789 if (rc) {
790 /* paranoid for a while -acme */
791 WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
792 __sock_put(sk);
793 }
794 return rc;
795}
796#define sk_del_node_init_rcu(sk) sk_del_node_init(sk)
797
798static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
799{
800 if (sk_hashed(sk)) {
801 hlist_nulls_del_init_rcu(n: &sk->sk_nulls_node);
802 return true;
803 }
804 return false;
805}
806
807static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
808{
809 bool rc = __sk_nulls_del_node_init_rcu(sk);
810
811 if (rc) {
812 /* paranoid for a while -acme */
813 WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
814 __sock_put(sk);
815 }
816 return rc;
817}
818
819static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
820{
821 hlist_add_head(n: &sk->sk_node, h: list);
822}
823
824static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
825{
826 sock_hold(sk);
827 __sk_add_node(sk, list);
828}
829
830static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
831{
832 sock_hold(sk);
833 if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
834 sk->sk_family == AF_INET6)
835 hlist_add_tail_rcu(n: &sk->sk_node, h: list);
836 else
837 hlist_add_head_rcu(n: &sk->sk_node, h: list);
838}
839
840static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list)
841{
842 sock_hold(sk);
843 hlist_add_tail_rcu(n: &sk->sk_node, h: list);
844}
845
846static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
847{
848 hlist_nulls_add_head_rcu(n: &sk->sk_nulls_node, h: list);
849}
850
851static inline void __sk_nulls_add_node_tail_rcu(struct sock *sk, struct hlist_nulls_head *list)
852{
853 hlist_nulls_add_tail_rcu(n: &sk->sk_nulls_node, h: list);
854}
855
856static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
857{
858 sock_hold(sk);
859 __sk_nulls_add_node_rcu(sk, list);
860}
861
862static inline void __sk_del_bind_node(struct sock *sk)
863{
864 __hlist_del(n: &sk->sk_bind_node);
865}
866
867static inline void sk_add_bind_node(struct sock *sk,
868 struct hlist_head *list)
869{
870 hlist_add_head(n: &sk->sk_bind_node, h: list);
871}
872
873#define sk_for_each(__sk, list) \
874 hlist_for_each_entry(__sk, list, sk_node)
875#define sk_for_each_rcu(__sk, list) \
876 hlist_for_each_entry_rcu(__sk, list, sk_node)
877#define sk_nulls_for_each(__sk, node, list) \
878 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
879#define sk_nulls_for_each_rcu(__sk, node, list) \
880 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
881#define sk_for_each_from(__sk) \
882 hlist_for_each_entry_from(__sk, sk_node)
883#define sk_nulls_for_each_from(__sk, node) \
884 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
885 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
886#define sk_for_each_safe(__sk, tmp, list) \
887 hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
888#define sk_for_each_bound(__sk, list) \
889 hlist_for_each_entry(__sk, list, sk_bind_node)
890
891/**
892 * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset
893 * @tpos: the type * to use as a loop cursor.
894 * @pos: the &struct hlist_node to use as a loop cursor.
895 * @head: the head for your list.
896 * @offset: offset of hlist_node within the struct.
897 *
898 */
899#define sk_for_each_entry_offset_rcu(tpos, pos, head, offset) \
900 for (pos = rcu_dereference(hlist_first_rcu(head)); \
901 pos != NULL && \
902 ({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \
903 pos = rcu_dereference(hlist_next_rcu(pos)))
904
905static inline struct user_namespace *sk_user_ns(const struct sock *sk)
906{
907 /* Careful only use this in a context where these parameters
908 * can not change and must all be valid, such as recvmsg from
909 * userspace.
910 */
911 return sk->sk_socket->file->f_cred->user_ns;
912}
913
914/* Sock flags */
915enum sock_flags {
916 SOCK_DEAD,
917 SOCK_DONE,
918 SOCK_URGINLINE,
919 SOCK_KEEPOPEN,
920 SOCK_LINGER,
921 SOCK_DESTROY,
922 SOCK_BROADCAST,
923 SOCK_TIMESTAMP,
924 SOCK_ZAPPED,
925 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
926 SOCK_DBG, /* %SO_DEBUG setting */
927 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
928 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
929 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
930 SOCK_MEMALLOC, /* VM depends on this socket for swapping */
931 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */
932 SOCK_FASYNC, /* fasync() active */
933 SOCK_RXQ_OVFL,
934 SOCK_ZEROCOPY, /* buffers from userspace */
935 SOCK_WIFI_STATUS, /* push wifi status to userspace */
936 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
937 * Will use last 4 bytes of packet sent from
938 * user-space instead.
939 */
940 SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
941 SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
942 SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */
943 SOCK_TXTIME,
944 SOCK_XDP, /* XDP is attached */
945 SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */
946 SOCK_RCVMARK, /* Receive SO_MARK ancillary data with packet */
947};
948
949#define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
950
951static inline void sock_copy_flags(struct sock *nsk, const struct sock *osk)
952{
953 nsk->sk_flags = osk->sk_flags;
954}
955
956static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
957{
958 __set_bit(flag, &sk->sk_flags);
959}
960
961static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
962{
963 __clear_bit(flag, &sk->sk_flags);
964}
965
966static inline void sock_valbool_flag(struct sock *sk, enum sock_flags bit,
967 int valbool)
968{
969 if (valbool)
970 sock_set_flag(sk, flag: bit);
971 else
972 sock_reset_flag(sk, flag: bit);
973}
974
975static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
976{
977 return test_bit(flag, &sk->sk_flags);
978}
979
980#ifdef CONFIG_NET
981DECLARE_STATIC_KEY_FALSE(memalloc_socks_key);
982static inline int sk_memalloc_socks(void)
983{
984 return static_branch_unlikely(&memalloc_socks_key);
985}
986
987void __receive_sock(struct file *file);
988#else
989
990static inline int sk_memalloc_socks(void)
991{
992 return 0;
993}
994
995static inline void __receive_sock(struct file *file)
996{ }
997#endif
998
999static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask)
1000{
1001 return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC);
1002}
1003
1004static inline void sk_acceptq_removed(struct sock *sk)
1005{
1006 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1);
1007}
1008
1009static inline void sk_acceptq_added(struct sock *sk)
1010{
1011 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1);
1012}
1013
1014/* Note: If you think the test should be:
1015 * return READ_ONCE(sk->sk_ack_backlog) >= READ_ONCE(sk->sk_max_ack_backlog);
1016 * Then please take a look at commit 64a146513f8f ("[NET]: Revert incorrect accept queue backlog changes.")
1017 */
1018static inline bool sk_acceptq_is_full(const struct sock *sk)
1019{
1020 return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(sk->sk_max_ack_backlog);
1021}
1022
1023/*
1024 * Compute minimal free write space needed to queue new packets.
1025 */
1026static inline int sk_stream_min_wspace(const struct sock *sk)
1027{
1028 return READ_ONCE(sk->sk_wmem_queued) >> 1;
1029}
1030
1031static inline int sk_stream_wspace(const struct sock *sk)
1032{
1033 return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued);
1034}
1035
1036static inline void sk_wmem_queued_add(struct sock *sk, int val)
1037{
1038 WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val);
1039}
1040
1041static inline void sk_forward_alloc_add(struct sock *sk, int val)
1042{
1043 /* Paired with lockless reads of sk->sk_forward_alloc */
1044 WRITE_ONCE(sk->sk_forward_alloc, sk->sk_forward_alloc + val);
1045}
1046
1047void sk_stream_write_space(struct sock *sk);
1048
1049/* OOB backlog add */
1050static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
1051{
1052 /* dont let skb dst not refcounted, we are going to leave rcu lock */
1053 skb_dst_force(skb);
1054
1055 if (!sk->sk_backlog.tail)
1056 WRITE_ONCE(sk->sk_backlog.head, skb);
1057 else
1058 sk->sk_backlog.tail->next = skb;
1059
1060 WRITE_ONCE(sk->sk_backlog.tail, skb);
1061 skb->next = NULL;
1062}
1063
1064/*
1065 * Take into account size of receive queue and backlog queue
1066 * Do not take into account this skb truesize,
1067 * to allow even a single big packet to come.
1068 */
1069static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
1070{
1071 unsigned int qsize = sk->sk_backlog.len + atomic_read(v: &sk->sk_rmem_alloc);
1072
1073 return qsize > limit;
1074}
1075
1076/* The per-socket spinlock must be held here. */
1077static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
1078 unsigned int limit)
1079{
1080 if (sk_rcvqueues_full(sk, limit))
1081 return -ENOBUFS;
1082
1083 /*
1084 * If the skb was allocated from pfmemalloc reserves, only
1085 * allow SOCK_MEMALLOC sockets to use it as this socket is
1086 * helping free memory
1087 */
1088 if (skb_pfmemalloc(skb) && !sock_flag(sk, flag: SOCK_MEMALLOC))
1089 return -ENOMEM;
1090
1091 __sk_add_backlog(sk, skb);
1092 sk->sk_backlog.len += skb->truesize;
1093 return 0;
1094}
1095
1096int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
1097
1098INDIRECT_CALLABLE_DECLARE(int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb));
1099INDIRECT_CALLABLE_DECLARE(int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb));
1100
1101static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
1102{
1103 if (sk_memalloc_socks() && skb_pfmemalloc(skb))
1104 return __sk_backlog_rcv(sk, skb);
1105
1106 return INDIRECT_CALL_INET(sk->sk_backlog_rcv,
1107 tcp_v6_do_rcv,
1108 tcp_v4_do_rcv,
1109 sk, skb);
1110}
1111
1112static inline void sk_incoming_cpu_update(struct sock *sk)
1113{
1114 int cpu = raw_smp_processor_id();
1115
1116 if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu))
1117 WRITE_ONCE(sk->sk_incoming_cpu, cpu);
1118}
1119
1120
1121static inline void sock_rps_save_rxhash(struct sock *sk,
1122 const struct sk_buff *skb)
1123{
1124#ifdef CONFIG_RPS
1125 /* The following WRITE_ONCE() is paired with the READ_ONCE()
1126 * here, and another one in sock_rps_record_flow().
1127 */
1128 if (unlikely(READ_ONCE(sk->sk_rxhash) != skb->hash))
1129 WRITE_ONCE(sk->sk_rxhash, skb->hash);
1130#endif
1131}
1132
1133static inline void sock_rps_reset_rxhash(struct sock *sk)
1134{
1135#ifdef CONFIG_RPS
1136 /* Paired with READ_ONCE() in sock_rps_record_flow() */
1137 WRITE_ONCE(sk->sk_rxhash, 0);
1138#endif
1139}
1140
1141#define sk_wait_event(__sk, __timeo, __condition, __wait) \
1142 ({ int __rc, __dis = __sk->sk_disconnects; \
1143 release_sock(__sk); \
1144 __rc = __condition; \
1145 if (!__rc) { \
1146 *(__timeo) = wait_woken(__wait, \
1147 TASK_INTERRUPTIBLE, \
1148 *(__timeo)); \
1149 } \
1150 sched_annotate_sleep(); \
1151 lock_sock(__sk); \
1152 __rc = __dis == __sk->sk_disconnects ? __condition : -EPIPE; \
1153 __rc; \
1154 })
1155
1156int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
1157int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
1158void sk_stream_wait_close(struct sock *sk, long timeo_p);
1159int sk_stream_error(struct sock *sk, int flags, int err);
1160void sk_stream_kill_queues(struct sock *sk);
1161void sk_set_memalloc(struct sock *sk);
1162void sk_clear_memalloc(struct sock *sk);
1163
1164void __sk_flush_backlog(struct sock *sk);
1165
1166static inline bool sk_flush_backlog(struct sock *sk)
1167{
1168 if (unlikely(READ_ONCE(sk->sk_backlog.tail))) {
1169 __sk_flush_backlog(sk);
1170 return true;
1171 }
1172 return false;
1173}
1174
1175int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb);
1176
1177struct request_sock_ops;
1178struct timewait_sock_ops;
1179struct inet_hashinfo;
1180struct raw_hashinfo;
1181struct smc_hashinfo;
1182struct module;
1183struct sk_psock;
1184
1185/*
1186 * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes
1187 * un-modified. Special care is taken when initializing object to zero.
1188 */
1189static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1190{
1191 if (offsetof(struct sock, sk_node.next) != 0)
1192 memset(sk, 0, offsetof(struct sock, sk_node.next));
1193 memset(&sk->sk_node.pprev, 0,
1194 size - offsetof(struct sock, sk_node.pprev));
1195}
1196
1197/* Networking protocol blocks we attach to sockets.
1198 * socket layer -> transport layer interface
1199 */
1200struct proto {
1201 void (*close)(struct sock *sk,
1202 long timeout);
1203 int (*pre_connect)(struct sock *sk,
1204 struct sockaddr *uaddr,
1205 int addr_len);
1206 int (*connect)(struct sock *sk,
1207 struct sockaddr *uaddr,
1208 int addr_len);
1209 int (*disconnect)(struct sock *sk, int flags);
1210
1211 struct sock * (*accept)(struct sock *sk, int flags, int *err,
1212 bool kern);
1213
1214 int (*ioctl)(struct sock *sk, int cmd,
1215 int *karg);
1216 int (*init)(struct sock *sk);
1217 void (*destroy)(struct sock *sk);
1218 void (*shutdown)(struct sock *sk, int how);
1219 int (*setsockopt)(struct sock *sk, int level,
1220 int optname, sockptr_t optval,
1221 unsigned int optlen);
1222 int (*getsockopt)(struct sock *sk, int level,
1223 int optname, char __user *optval,
1224 int __user *option);
1225 void (*keepalive)(struct sock *sk, int valbool);
1226#ifdef CONFIG_COMPAT
1227 int (*compat_ioctl)(struct sock *sk,
1228 unsigned int cmd, unsigned long arg);
1229#endif
1230 int (*sendmsg)(struct sock *sk, struct msghdr *msg,
1231 size_t len);
1232 int (*recvmsg)(struct sock *sk, struct msghdr *msg,
1233 size_t len, int flags, int *addr_len);
1234 void (*splice_eof)(struct socket *sock);
1235 int (*bind)(struct sock *sk,
1236 struct sockaddr *addr, int addr_len);
1237 int (*bind_add)(struct sock *sk,
1238 struct sockaddr *addr, int addr_len);
1239
1240 int (*backlog_rcv) (struct sock *sk,
1241 struct sk_buff *skb);
1242 bool (*bpf_bypass_getsockopt)(int level,
1243 int optname);
1244
1245 void (*release_cb)(struct sock *sk);
1246
1247 /* Keeping track of sk's, looking them up, and port selection methods. */
1248 int (*hash)(struct sock *sk);
1249 void (*unhash)(struct sock *sk);
1250 void (*rehash)(struct sock *sk);
1251 int (*get_port)(struct sock *sk, unsigned short snum);
1252 void (*put_port)(struct sock *sk);
1253#ifdef CONFIG_BPF_SYSCALL
1254 int (*psock_update_sk_prot)(struct sock *sk,
1255 struct sk_psock *psock,
1256 bool restore);
1257#endif
1258
1259 /* Keeping track of sockets in use */
1260#ifdef CONFIG_PROC_FS
1261 unsigned int inuse_idx;
1262#endif
1263
1264#if IS_ENABLED(CONFIG_MPTCP)
1265 int (*forward_alloc_get)(const struct sock *sk);
1266#endif
1267
1268 bool (*stream_memory_free)(const struct sock *sk, int wake);
1269 bool (*sock_is_readable)(struct sock *sk);
1270 /* Memory pressure */
1271 void (*enter_memory_pressure)(struct sock *sk);
1272 void (*leave_memory_pressure)(struct sock *sk);
1273 atomic_long_t *memory_allocated; /* Current allocated memory. */
1274 int __percpu *per_cpu_fw_alloc;
1275 struct percpu_counter *sockets_allocated; /* Current number of sockets. */
1276
1277 /*
1278 * Pressure flag: try to collapse.
1279 * Technical note: it is used by multiple contexts non atomically.
1280 * Make sure to use READ_ONCE()/WRITE_ONCE() for all reads/writes.
1281 * All the __sk_mem_schedule() is of this nature: accounting
1282 * is strict, actions are advisory and have some latency.
1283 */
1284 unsigned long *memory_pressure;
1285 long *sysctl_mem;
1286
1287 int *sysctl_wmem;
1288 int *sysctl_rmem;
1289 u32 sysctl_wmem_offset;
1290 u32 sysctl_rmem_offset;
1291
1292 int max_header;
1293 bool no_autobind;
1294
1295 struct kmem_cache *slab;
1296 unsigned int obj_size;
1297 unsigned int ipv6_pinfo_offset;
1298 slab_flags_t slab_flags;
1299 unsigned int useroffset; /* Usercopy region offset */
1300 unsigned int usersize; /* Usercopy region size */
1301
1302 unsigned int __percpu *orphan_count;
1303
1304 struct request_sock_ops *rsk_prot;
1305 struct timewait_sock_ops *twsk_prot;
1306
1307 union {
1308 struct inet_hashinfo *hashinfo;
1309 struct udp_table *udp_table;
1310 struct raw_hashinfo *raw_hash;
1311 struct smc_hashinfo *smc_hash;
1312 } h;
1313
1314 struct module *owner;
1315
1316 char name[32];
1317
1318 struct list_head node;
1319 int (*diag_destroy)(struct sock *sk, int err);
1320} __randomize_layout;
1321
1322int proto_register(struct proto *prot, int alloc_slab);
1323void proto_unregister(struct proto *prot);
1324int sock_load_diag_module(int family, int protocol);
1325
1326INDIRECT_CALLABLE_DECLARE(bool tcp_stream_memory_free(const struct sock *sk, int wake));
1327
1328static inline int sk_forward_alloc_get(const struct sock *sk)
1329{
1330#if IS_ENABLED(CONFIG_MPTCP)
1331 if (sk->sk_prot->forward_alloc_get)
1332 return sk->sk_prot->forward_alloc_get(sk);
1333#endif
1334 return READ_ONCE(sk->sk_forward_alloc);
1335}
1336
1337static inline bool __sk_stream_memory_free(const struct sock *sk, int wake)
1338{
1339 if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf))
1340 return false;
1341
1342 return sk->sk_prot->stream_memory_free ?
1343 INDIRECT_CALL_INET_1(sk->sk_prot->stream_memory_free,
1344 tcp_stream_memory_free, sk, wake) : true;
1345}
1346
1347static inline bool sk_stream_memory_free(const struct sock *sk)
1348{
1349 return __sk_stream_memory_free(sk, wake: 0);
1350}
1351
1352static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake)
1353{
1354 return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
1355 __sk_stream_memory_free(sk, wake);
1356}
1357
1358static inline bool sk_stream_is_writeable(const struct sock *sk)
1359{
1360 return __sk_stream_is_writeable(sk, wake: 0);
1361}
1362
1363static inline int sk_under_cgroup_hierarchy(struct sock *sk,
1364 struct cgroup *ancestor)
1365{
1366#ifdef CONFIG_SOCK_CGROUP_DATA
1367 return cgroup_is_descendant(cgrp: sock_cgroup_ptr(skcd: &sk->sk_cgrp_data),
1368 ancestor);
1369#else
1370 return -ENOTSUPP;
1371#endif
1372}
1373
1374static inline bool sk_has_memory_pressure(const struct sock *sk)
1375{
1376 return sk->sk_prot->memory_pressure != NULL;
1377}
1378
1379static inline bool sk_under_global_memory_pressure(const struct sock *sk)
1380{
1381 return sk->sk_prot->memory_pressure &&
1382 !!READ_ONCE(*sk->sk_prot->memory_pressure);
1383}
1384
1385static inline bool sk_under_memory_pressure(const struct sock *sk)
1386{
1387 if (!sk->sk_prot->memory_pressure)
1388 return false;
1389
1390 if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
1391 mem_cgroup_under_socket_pressure(memcg: sk->sk_memcg))
1392 return true;
1393
1394 return !!READ_ONCE(*sk->sk_prot->memory_pressure);
1395}
1396
1397static inline long
1398proto_memory_allocated(const struct proto *prot)
1399{
1400 return max(0L, atomic_long_read(prot->memory_allocated));
1401}
1402
1403static inline long
1404sk_memory_allocated(const struct sock *sk)
1405{
1406 return proto_memory_allocated(prot: sk->sk_prot);
1407}
1408
1409/* 1 MB per cpu, in page units */
1410#define SK_MEMORY_PCPU_RESERVE (1 << (20 - PAGE_SHIFT))
1411extern int sysctl_mem_pcpu_rsv;
1412
1413static inline void
1414sk_memory_allocated_add(struct sock *sk, int amt)
1415{
1416 int local_reserve;
1417
1418 preempt_disable();
1419 local_reserve = __this_cpu_add_return(*sk->sk_prot->per_cpu_fw_alloc, amt);
1420 if (local_reserve >= READ_ONCE(sysctl_mem_pcpu_rsv)) {
1421 __this_cpu_sub(*sk->sk_prot->per_cpu_fw_alloc, local_reserve);
1422 atomic_long_add(i: local_reserve, v: sk->sk_prot->memory_allocated);
1423 }
1424 preempt_enable();
1425}
1426
1427static inline void
1428sk_memory_allocated_sub(struct sock *sk, int amt)
1429{
1430 int local_reserve;
1431
1432 preempt_disable();
1433 local_reserve = __this_cpu_sub_return(*sk->sk_prot->per_cpu_fw_alloc, amt);
1434 if (local_reserve <= -READ_ONCE(sysctl_mem_pcpu_rsv)) {
1435 __this_cpu_sub(*sk->sk_prot->per_cpu_fw_alloc, local_reserve);
1436 atomic_long_add(i: local_reserve, v: sk->sk_prot->memory_allocated);
1437 }
1438 preempt_enable();
1439}
1440
1441#define SK_ALLOC_PERCPU_COUNTER_BATCH 16
1442
1443static inline void sk_sockets_allocated_dec(struct sock *sk)
1444{
1445 percpu_counter_add_batch(fbc: sk->sk_prot->sockets_allocated, amount: -1,
1446 SK_ALLOC_PERCPU_COUNTER_BATCH);
1447}
1448
1449static inline void sk_sockets_allocated_inc(struct sock *sk)
1450{
1451 percpu_counter_add_batch(fbc: sk->sk_prot->sockets_allocated, amount: 1,
1452 SK_ALLOC_PERCPU_COUNTER_BATCH);
1453}
1454
1455static inline u64
1456sk_sockets_allocated_read_positive(struct sock *sk)
1457{
1458 return percpu_counter_read_positive(fbc: sk->sk_prot->sockets_allocated);
1459}
1460
1461static inline int
1462proto_sockets_allocated_sum_positive(struct proto *prot)
1463{
1464 return percpu_counter_sum_positive(fbc: prot->sockets_allocated);
1465}
1466
1467static inline bool
1468proto_memory_pressure(struct proto *prot)
1469{
1470 if (!prot->memory_pressure)
1471 return false;
1472 return !!READ_ONCE(*prot->memory_pressure);
1473}
1474
1475
1476#ifdef CONFIG_PROC_FS
1477#define PROTO_INUSE_NR 64 /* should be enough for the first time */
1478struct prot_inuse {
1479 int all;
1480 int val[PROTO_INUSE_NR];
1481};
1482
1483static inline void sock_prot_inuse_add(const struct net *net,
1484 const struct proto *prot, int val)
1485{
1486 this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val);
1487}
1488
1489static inline void sock_inuse_add(const struct net *net, int val)
1490{
1491 this_cpu_add(net->core.prot_inuse->all, val);
1492}
1493
1494int sock_prot_inuse_get(struct net *net, struct proto *proto);
1495int sock_inuse_get(struct net *net);
1496#else
1497static inline void sock_prot_inuse_add(const struct net *net,
1498 const struct proto *prot, int val)
1499{
1500}
1501
1502static inline void sock_inuse_add(const struct net *net, int val)
1503{
1504}
1505#endif
1506
1507
1508/* With per-bucket locks this operation is not-atomic, so that
1509 * this version is not worse.
1510 */
1511static inline int __sk_prot_rehash(struct sock *sk)
1512{
1513 sk->sk_prot->unhash(sk);
1514 return sk->sk_prot->hash(sk);
1515}
1516
1517/* About 10 seconds */
1518#define SOCK_DESTROY_TIME (10*HZ)
1519
1520/* Sockets 0-1023 can't be bound to unless you are superuser */
1521#define PROT_SOCK 1024
1522
1523#define SHUTDOWN_MASK 3
1524#define RCV_SHUTDOWN 1
1525#define SEND_SHUTDOWN 2
1526
1527#define SOCK_BINDADDR_LOCK 4
1528#define SOCK_BINDPORT_LOCK 8
1529
1530struct socket_alloc {
1531 struct socket socket;
1532 struct inode vfs_inode;
1533};
1534
1535static inline struct socket *SOCKET_I(struct inode *inode)
1536{
1537 return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1538}
1539
1540static inline struct inode *SOCK_INODE(struct socket *socket)
1541{
1542 return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1543}
1544
1545/*
1546 * Functions for memory accounting
1547 */
1548int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind);
1549int __sk_mem_schedule(struct sock *sk, int size, int kind);
1550void __sk_mem_reduce_allocated(struct sock *sk, int amount);
1551void __sk_mem_reclaim(struct sock *sk, int amount);
1552
1553#define SK_MEM_SEND 0
1554#define SK_MEM_RECV 1
1555
1556/* sysctl_mem values are in pages */
1557static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1558{
1559 return READ_ONCE(sk->sk_prot->sysctl_mem[index]);
1560}
1561
1562static inline int sk_mem_pages(int amt)
1563{
1564 return (amt + PAGE_SIZE - 1) >> PAGE_SHIFT;
1565}
1566
1567static inline bool sk_has_account(struct sock *sk)
1568{
1569 /* return true if protocol supports memory accounting */
1570 return !!sk->sk_prot->memory_allocated;
1571}
1572
1573static inline bool sk_wmem_schedule(struct sock *sk, int size)
1574{
1575 int delta;
1576
1577 if (!sk_has_account(sk))
1578 return true;
1579 delta = size - sk->sk_forward_alloc;
1580 return delta <= 0 || __sk_mem_schedule(sk, size: delta, SK_MEM_SEND);
1581}
1582
1583static inline bool
1584sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
1585{
1586 int delta;
1587
1588 if (!sk_has_account(sk))
1589 return true;
1590 delta = size - sk->sk_forward_alloc;
1591 return delta <= 0 || __sk_mem_schedule(sk, size: delta, SK_MEM_RECV) ||
1592 skb_pfmemalloc(skb);
1593}
1594
1595static inline int sk_unused_reserved_mem(const struct sock *sk)
1596{
1597 int unused_mem;
1598
1599 if (likely(!sk->sk_reserved_mem))
1600 return 0;
1601
1602 unused_mem = sk->sk_reserved_mem - sk->sk_wmem_queued -
1603 atomic_read(v: &sk->sk_rmem_alloc);
1604
1605 return unused_mem > 0 ? unused_mem : 0;
1606}
1607
1608static inline void sk_mem_reclaim(struct sock *sk)
1609{
1610 int reclaimable;
1611
1612 if (!sk_has_account(sk))
1613 return;
1614
1615 reclaimable = sk->sk_forward_alloc - sk_unused_reserved_mem(sk);
1616
1617 if (reclaimable >= (int)PAGE_SIZE)
1618 __sk_mem_reclaim(sk, amount: reclaimable);
1619}
1620
1621static inline void sk_mem_reclaim_final(struct sock *sk)
1622{
1623 sk->sk_reserved_mem = 0;
1624 sk_mem_reclaim(sk);
1625}
1626
1627static inline void sk_mem_charge(struct sock *sk, int size)
1628{
1629 if (!sk_has_account(sk))
1630 return;
1631 sk_forward_alloc_add(sk, val: -size);
1632}
1633
1634static inline void sk_mem_uncharge(struct sock *sk, int size)
1635{
1636 if (!sk_has_account(sk))
1637 return;
1638 sk_forward_alloc_add(sk, val: size);
1639 sk_mem_reclaim(sk);
1640}
1641
1642/*
1643 * Macro so as to not evaluate some arguments when
1644 * lockdep is not enabled.
1645 *
1646 * Mark both the sk_lock and the sk_lock.slock as a
1647 * per-address-family lock class.
1648 */
1649#define sock_lock_init_class_and_name(sk, sname, skey, name, key) \
1650do { \
1651 sk->sk_lock.owned = 0; \
1652 init_waitqueue_head(&sk->sk_lock.wq); \
1653 spin_lock_init(&(sk)->sk_lock.slock); \
1654 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \
1655 sizeof((sk)->sk_lock)); \
1656 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \
1657 (skey), (sname)); \
1658 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \
1659} while (0)
1660
1661static inline bool lockdep_sock_is_held(const struct sock *sk)
1662{
1663 return lockdep_is_held(&sk->sk_lock) ||
1664 lockdep_is_held(&sk->sk_lock.slock);
1665}
1666
1667void lock_sock_nested(struct sock *sk, int subclass);
1668
1669static inline void lock_sock(struct sock *sk)
1670{
1671 lock_sock_nested(sk, subclass: 0);
1672}
1673
1674void __lock_sock(struct sock *sk);
1675void __release_sock(struct sock *sk);
1676void release_sock(struct sock *sk);
1677
1678/* BH context may only use the following locking interface. */
1679#define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock))
1680#define bh_lock_sock_nested(__sk) \
1681 spin_lock_nested(&((__sk)->sk_lock.slock), \
1682 SINGLE_DEPTH_NESTING)
1683#define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock))
1684
1685bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock);
1686
1687/**
1688 * lock_sock_fast - fast version of lock_sock
1689 * @sk: socket
1690 *
1691 * This version should be used for very small section, where process wont block
1692 * return false if fast path is taken:
1693 *
1694 * sk_lock.slock locked, owned = 0, BH disabled
1695 *
1696 * return true if slow path is taken:
1697 *
1698 * sk_lock.slock unlocked, owned = 1, BH enabled
1699 */
1700static inline bool lock_sock_fast(struct sock *sk)
1701{
1702 /* The sk_lock has mutex_lock() semantics here. */
1703 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
1704
1705 return __lock_sock_fast(sk);
1706}
1707
1708/* fast socket lock variant for caller already holding a [different] socket lock */
1709static inline bool lock_sock_fast_nested(struct sock *sk)
1710{
1711 mutex_acquire(&sk->sk_lock.dep_map, SINGLE_DEPTH_NESTING, 0, _RET_IP_);
1712
1713 return __lock_sock_fast(sk);
1714}
1715
1716/**
1717 * unlock_sock_fast - complement of lock_sock_fast
1718 * @sk: socket
1719 * @slow: slow mode
1720 *
1721 * fast unlock socket for user context.
1722 * If slow mode is on, we call regular release_sock()
1723 */
1724static inline void unlock_sock_fast(struct sock *sk, bool slow)
1725 __releases(&sk->sk_lock.slock)
1726{
1727 if (slow) {
1728 release_sock(sk);
1729 __release(&sk->sk_lock.slock);
1730 } else {
1731 mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1732 spin_unlock_bh(lock: &sk->sk_lock.slock);
1733 }
1734}
1735
1736void sockopt_lock_sock(struct sock *sk);
1737void sockopt_release_sock(struct sock *sk);
1738bool sockopt_ns_capable(struct user_namespace *ns, int cap);
1739bool sockopt_capable(int cap);
1740
1741/* Used by processes to "lock" a socket state, so that
1742 * interrupts and bottom half handlers won't change it
1743 * from under us. It essentially blocks any incoming
1744 * packets, so that we won't get any new data or any
1745 * packets that change the state of the socket.
1746 *
1747 * While locked, BH processing will add new packets to
1748 * the backlog queue. This queue is processed by the
1749 * owner of the socket lock right before it is released.
1750 *
1751 * Since ~2.3.5 it is also exclusive sleep lock serializing
1752 * accesses from user process context.
1753 */
1754
1755static inline void sock_owned_by_me(const struct sock *sk)
1756{
1757#ifdef CONFIG_LOCKDEP
1758 WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
1759#endif
1760}
1761
1762static inline void sock_not_owned_by_me(const struct sock *sk)
1763{
1764#ifdef CONFIG_LOCKDEP
1765 WARN_ON_ONCE(lockdep_sock_is_held(sk) && debug_locks);
1766#endif
1767}
1768
1769static inline bool sock_owned_by_user(const struct sock *sk)
1770{
1771 sock_owned_by_me(sk);
1772 return sk->sk_lock.owned;
1773}
1774
1775static inline bool sock_owned_by_user_nocheck(const struct sock *sk)
1776{
1777 return sk->sk_lock.owned;
1778}
1779
1780static inline void sock_release_ownership(struct sock *sk)
1781{
1782 DEBUG_NET_WARN_ON_ONCE(!sock_owned_by_user_nocheck(sk));
1783 sk->sk_lock.owned = 0;
1784
1785 /* The sk_lock has mutex_unlock() semantics: */
1786 mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1787}
1788
1789/* no reclassification while locks are held */
1790static inline bool sock_allow_reclassification(const struct sock *csk)
1791{
1792 struct sock *sk = (struct sock *)csk;
1793
1794 return !sock_owned_by_user_nocheck(sk) &&
1795 !spin_is_locked(lock: &sk->sk_lock.slock);
1796}
1797
1798struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1799 struct proto *prot, int kern);
1800void sk_free(struct sock *sk);
1801void sk_destruct(struct sock *sk);
1802struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
1803void sk_free_unlock_clone(struct sock *sk);
1804
1805struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1806 gfp_t priority);
1807void __sock_wfree(struct sk_buff *skb);
1808void sock_wfree(struct sk_buff *skb);
1809struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1810 gfp_t priority);
1811void skb_orphan_partial(struct sk_buff *skb);
1812void sock_rfree(struct sk_buff *skb);
1813void sock_efree(struct sk_buff *skb);
1814#ifdef CONFIG_INET
1815void sock_edemux(struct sk_buff *skb);
1816void sock_pfree(struct sk_buff *skb);
1817#else
1818#define sock_edemux sock_efree
1819#endif
1820
1821int sk_setsockopt(struct sock *sk, int level, int optname,
1822 sockptr_t optval, unsigned int optlen);
1823int sock_setsockopt(struct socket *sock, int level, int op,
1824 sockptr_t optval, unsigned int optlen);
1825int do_sock_setsockopt(struct socket *sock, bool compat, int level,
1826 int optname, sockptr_t optval, int optlen);
1827int do_sock_getsockopt(struct socket *sock, bool compat, int level,
1828 int optname, sockptr_t optval, sockptr_t optlen);
1829
1830int sk_getsockopt(struct sock *sk, int level, int optname,
1831 sockptr_t optval, sockptr_t optlen);
1832int sock_gettstamp(struct socket *sock, void __user *userstamp,
1833 bool timeval, bool time32);
1834struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1835 unsigned long data_len, int noblock,
1836 int *errcode, int max_page_order);
1837
1838static inline struct sk_buff *sock_alloc_send_skb(struct sock *sk,
1839 unsigned long size,
1840 int noblock, int *errcode)
1841{
1842 return sock_alloc_send_pskb(sk, header_len: size, data_len: 0, noblock, errcode, max_page_order: 0);
1843}
1844
1845void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
1846void sock_kfree_s(struct sock *sk, void *mem, int size);
1847void sock_kzfree_s(struct sock *sk, void *mem, int size);
1848void sk_send_sigurg(struct sock *sk);
1849
1850static inline void sock_replace_proto(struct sock *sk, struct proto *proto)
1851{
1852 if (sk->sk_socket)
1853 clear_bit(SOCK_SUPPORT_ZC, addr: &sk->sk_socket->flags);
1854 WRITE_ONCE(sk->sk_prot, proto);
1855}
1856
1857struct sockcm_cookie {
1858 u64 transmit_time;
1859 u32 mark;
1860 u32 tsflags;
1861};
1862
1863static inline void sockcm_init(struct sockcm_cookie *sockc,
1864 const struct sock *sk)
1865{
1866 *sockc = (struct sockcm_cookie) {
1867 .tsflags = READ_ONCE(sk->sk_tsflags)
1868 };
1869}
1870
1871int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
1872 struct sockcm_cookie *sockc);
1873int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1874 struct sockcm_cookie *sockc);
1875
1876/*
1877 * Functions to fill in entries in struct proto_ops when a protocol
1878 * does not implement a particular function.
1879 */
1880int sock_no_bind(struct socket *, struct sockaddr *, int);
1881int sock_no_connect(struct socket *, struct sockaddr *, int, int);
1882int sock_no_socketpair(struct socket *, struct socket *);
1883int sock_no_accept(struct socket *, struct socket *, int, bool);
1884int sock_no_getname(struct socket *, struct sockaddr *, int);
1885int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
1886int sock_no_listen(struct socket *, int);
1887int sock_no_shutdown(struct socket *, int);
1888int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
1889int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
1890int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
1891int sock_no_mmap(struct file *file, struct socket *sock,
1892 struct vm_area_struct *vma);
1893
1894/*
1895 * Functions to fill in entries in struct proto_ops when a protocol
1896 * uses the inet style.
1897 */
1898int sock_common_getsockopt(struct socket *sock, int level, int optname,
1899 char __user *optval, int __user *optlen);
1900int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1901 int flags);
1902int sock_common_setsockopt(struct socket *sock, int level, int optname,
1903 sockptr_t optval, unsigned int optlen);
1904
1905void sk_common_release(struct sock *sk);
1906
1907/*
1908 * Default socket callbacks and setup code
1909 */
1910
1911/* Initialise core socket variables using an explicit uid. */
1912void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid);
1913
1914/* Initialise core socket variables.
1915 * Assumes struct socket *sock is embedded in a struct socket_alloc.
1916 */
1917void sock_init_data(struct socket *sock, struct sock *sk);
1918
1919/*
1920 * Socket reference counting postulates.
1921 *
1922 * * Each user of socket SHOULD hold a reference count.
1923 * * Each access point to socket (an hash table bucket, reference from a list,
1924 * running timer, skb in flight MUST hold a reference count.
1925 * * When reference count hits 0, it means it will never increase back.
1926 * * When reference count hits 0, it means that no references from
1927 * outside exist to this socket and current process on current CPU
1928 * is last user and may/should destroy this socket.
1929 * * sk_free is called from any context: process, BH, IRQ. When
1930 * it is called, socket has no references from outside -> sk_free
1931 * may release descendant resources allocated by the socket, but
1932 * to the time when it is called, socket is NOT referenced by any
1933 * hash tables, lists etc.
1934 * * Packets, delivered from outside (from network or from another process)
1935 * and enqueued on receive/error queues SHOULD NOT grab reference count,
1936 * when they sit in queue. Otherwise, packets will leak to hole, when
1937 * socket is looked up by one cpu and unhasing is made by another CPU.
1938 * It is true for udp/raw, netlink (leak to receive and error queues), tcp
1939 * (leak to backlog). Packet socket does all the processing inside
1940 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1941 * use separate SMP lock, so that they are prone too.
1942 */
1943
1944/* Ungrab socket and destroy it, if it was the last reference. */
1945static inline void sock_put(struct sock *sk)
1946{
1947 if (refcount_dec_and_test(r: &sk->sk_refcnt))
1948 sk_free(sk);
1949}
1950/* Generic version of sock_put(), dealing with all sockets
1951 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
1952 */
1953void sock_gen_put(struct sock *sk);
1954
1955int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested,
1956 unsigned int trim_cap, bool refcounted);
1957static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1958 const int nested)
1959{
1960 return __sk_receive_skb(sk, skb, nested, trim_cap: 1, refcounted: true);
1961}
1962
1963static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1964{
1965 /* sk_tx_queue_mapping accept only upto a 16-bit value */
1966 if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX))
1967 return;
1968 /* Paired with READ_ONCE() in sk_tx_queue_get() and
1969 * other WRITE_ONCE() because socket lock might be not held.
1970 */
1971 WRITE_ONCE(sk->sk_tx_queue_mapping, tx_queue);
1972}
1973
1974#define NO_QUEUE_MAPPING USHRT_MAX
1975
1976static inline void sk_tx_queue_clear(struct sock *sk)
1977{
1978 /* Paired with READ_ONCE() in sk_tx_queue_get() and
1979 * other WRITE_ONCE() because socket lock might be not held.
1980 */
1981 WRITE_ONCE(sk->sk_tx_queue_mapping, NO_QUEUE_MAPPING);
1982}
1983
1984static inline int sk_tx_queue_get(const struct sock *sk)
1985{
1986 if (sk) {
1987 /* Paired with WRITE_ONCE() in sk_tx_queue_clear()
1988 * and sk_tx_queue_set().
1989 */
1990 int val = READ_ONCE(sk->sk_tx_queue_mapping);
1991
1992 if (val != NO_QUEUE_MAPPING)
1993 return val;
1994 }
1995 return -1;
1996}
1997
1998static inline void __sk_rx_queue_set(struct sock *sk,
1999 const struct sk_buff *skb,
2000 bool force_set)
2001{
2002#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
2003 if (skb_rx_queue_recorded(skb)) {
2004 u16 rx_queue = skb_get_rx_queue(skb);
2005
2006 if (force_set ||
2007 unlikely(READ_ONCE(sk->sk_rx_queue_mapping) != rx_queue))
2008 WRITE_ONCE(sk->sk_rx_queue_mapping, rx_queue);
2009 }
2010#endif
2011}
2012
2013static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb)
2014{
2015 __sk_rx_queue_set(sk, skb, force_set: true);
2016}
2017
2018static inline void sk_rx_queue_update(struct sock *sk, const struct sk_buff *skb)
2019{
2020 __sk_rx_queue_set(sk, skb, force_set: false);
2021}
2022
2023static inline void sk_rx_queue_clear(struct sock *sk)
2024{
2025#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
2026 WRITE_ONCE(sk->sk_rx_queue_mapping, NO_QUEUE_MAPPING);
2027#endif
2028}
2029
2030static inline int sk_rx_queue_get(const struct sock *sk)
2031{
2032#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
2033 if (sk) {
2034 int res = READ_ONCE(sk->sk_rx_queue_mapping);
2035
2036 if (res != NO_QUEUE_MAPPING)
2037 return res;
2038 }
2039#endif
2040
2041 return -1;
2042}
2043
2044static inline void sk_set_socket(struct sock *sk, struct socket *sock)
2045{
2046 sk->sk_socket = sock;
2047}
2048
2049static inline wait_queue_head_t *sk_sleep(struct sock *sk)
2050{
2051 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
2052 return &rcu_dereference_raw(sk->sk_wq)->wait;
2053}
2054/* Detach socket from process context.
2055 * Announce socket dead, detach it from wait queue and inode.
2056 * Note that parent inode held reference count on this struct sock,
2057 * we do not release it in this function, because protocol
2058 * probably wants some additional cleanups or even continuing
2059 * to work with this socket (TCP).
2060 */
2061static inline void sock_orphan(struct sock *sk)
2062{
2063 write_lock_bh(&sk->sk_callback_lock);
2064 sock_set_flag(sk, flag: SOCK_DEAD);
2065 sk_set_socket(sk, NULL);
2066 sk->sk_wq = NULL;
2067 write_unlock_bh(&sk->sk_callback_lock);
2068}
2069
2070static inline void sock_graft(struct sock *sk, struct socket *parent)
2071{
2072 WARN_ON(parent->sk);
2073 write_lock_bh(&sk->sk_callback_lock);
2074 rcu_assign_pointer(sk->sk_wq, &parent->wq);
2075 parent->sk = sk;
2076 sk_set_socket(sk, sock: parent);
2077 sk->sk_uid = SOCK_INODE(socket: parent)->i_uid;
2078 security_sock_graft(sk, parent);
2079 write_unlock_bh(&sk->sk_callback_lock);
2080}
2081
2082kuid_t sock_i_uid(struct sock *sk);
2083unsigned long __sock_i_ino(struct sock *sk);
2084unsigned long sock_i_ino(struct sock *sk);
2085
2086static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk)
2087{
2088 return sk ? sk->sk_uid : make_kuid(from: net->user_ns, uid: 0);
2089}
2090
2091static inline u32 net_tx_rndhash(void)
2092{
2093 u32 v = get_random_u32();
2094
2095 return v ?: 1;
2096}
2097
2098static inline void sk_set_txhash(struct sock *sk)
2099{
2100 /* This pairs with READ_ONCE() in skb_set_hash_from_sk() */
2101 WRITE_ONCE(sk->sk_txhash, net_tx_rndhash());
2102}
2103
2104static inline bool sk_rethink_txhash(struct sock *sk)
2105{
2106 if (sk->sk_txhash && sk->sk_txrehash == SOCK_TXREHASH_ENABLED) {
2107 sk_set_txhash(sk);
2108 return true;
2109 }
2110 return false;
2111}
2112
2113static inline struct dst_entry *
2114__sk_dst_get(const struct sock *sk)
2115{
2116 return rcu_dereference_check(sk->sk_dst_cache,
2117 lockdep_sock_is_held(sk));
2118}
2119
2120static inline struct dst_entry *
2121sk_dst_get(const struct sock *sk)
2122{
2123 struct dst_entry *dst;
2124
2125 rcu_read_lock();
2126 dst = rcu_dereference(sk->sk_dst_cache);
2127 if (dst && !rcuref_get(ref: &dst->__rcuref))
2128 dst = NULL;
2129 rcu_read_unlock();
2130 return dst;
2131}
2132
2133static inline void __dst_negative_advice(struct sock *sk)
2134{
2135 struct dst_entry *ndst, *dst = __sk_dst_get(sk);
2136
2137 if (dst && dst->ops->negative_advice) {
2138 ndst = dst->ops->negative_advice(dst);
2139
2140 if (ndst != dst) {
2141 rcu_assign_pointer(sk->sk_dst_cache, ndst);
2142 sk_tx_queue_clear(sk);
2143 WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2144 }
2145 }
2146}
2147
2148static inline void dst_negative_advice(struct sock *sk)
2149{
2150 sk_rethink_txhash(sk);
2151 __dst_negative_advice(sk);
2152}
2153
2154static inline void
2155__sk_dst_set(struct sock *sk, struct dst_entry *dst)
2156{
2157 struct dst_entry *old_dst;
2158
2159 sk_tx_queue_clear(sk);
2160 WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2161 old_dst = rcu_dereference_protected(sk->sk_dst_cache,
2162 lockdep_sock_is_held(sk));
2163 rcu_assign_pointer(sk->sk_dst_cache, dst);
2164 dst_release(dst: old_dst);
2165}
2166
2167static inline void
2168sk_dst_set(struct sock *sk, struct dst_entry *dst)
2169{
2170 struct dst_entry *old_dst;
2171
2172 sk_tx_queue_clear(sk);
2173 WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2174 old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst);
2175 dst_release(dst: old_dst);
2176}
2177
2178static inline void
2179__sk_dst_reset(struct sock *sk)
2180{
2181 __sk_dst_set(sk, NULL);
2182}
2183
2184static inline void
2185sk_dst_reset(struct sock *sk)
2186{
2187 sk_dst_set(sk, NULL);
2188}
2189
2190struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
2191
2192struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
2193
2194static inline void sk_dst_confirm(struct sock *sk)
2195{
2196 if (!READ_ONCE(sk->sk_dst_pending_confirm))
2197 WRITE_ONCE(sk->sk_dst_pending_confirm, 1);
2198}
2199
2200static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n)
2201{
2202 if (skb_get_dst_pending_confirm(skb)) {
2203 struct sock *sk = skb->sk;
2204
2205 if (sk && READ_ONCE(sk->sk_dst_pending_confirm))
2206 WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2207 neigh_confirm(n);
2208 }
2209}
2210
2211bool sk_mc_loop(const struct sock *sk);
2212
2213static inline bool sk_can_gso(const struct sock *sk)
2214{
2215 return net_gso_ok(features: sk->sk_route_caps, gso_type: sk->sk_gso_type);
2216}
2217
2218void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
2219
2220static inline void sk_gso_disable(struct sock *sk)
2221{
2222 sk->sk_gso_disabled = 1;
2223 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2224}
2225
2226static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
2227 struct iov_iter *from, char *to,
2228 int copy, int offset)
2229{
2230 if (skb->ip_summed == CHECKSUM_NONE) {
2231 __wsum csum = 0;
2232 if (!csum_and_copy_from_iter_full(addr: to, bytes: copy, csum: &csum, i: from))
2233 return -EFAULT;
2234 skb->csum = csum_block_add(csum: skb->csum, csum2: csum, offset);
2235 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
2236 if (!copy_from_iter_full_nocache(addr: to, bytes: copy, i: from))
2237 return -EFAULT;
2238 } else if (!copy_from_iter_full(addr: to, bytes: copy, i: from))
2239 return -EFAULT;
2240
2241 return 0;
2242}
2243
2244static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
2245 struct iov_iter *from, int copy)
2246{
2247 int err, offset = skb->len;
2248
2249 err = skb_do_copy_data_nocache(sk, skb, from, to: skb_put(skb, len: copy),
2250 copy, offset);
2251 if (err)
2252 __skb_trim(skb, len: offset);
2253
2254 return err;
2255}
2256
2257static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
2258 struct sk_buff *skb,
2259 struct page *page,
2260 int off, int copy)
2261{
2262 int err;
2263
2264 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
2265 copy, offset: skb->len);
2266 if (err)
2267 return err;
2268
2269 skb_len_add(skb, delta: copy);
2270 sk_wmem_queued_add(sk, val: copy);
2271 sk_mem_charge(sk, size: copy);
2272 return 0;
2273}
2274
2275/**
2276 * sk_wmem_alloc_get - returns write allocations
2277 * @sk: socket
2278 *
2279 * Return: sk_wmem_alloc minus initial offset of one
2280 */
2281static inline int sk_wmem_alloc_get(const struct sock *sk)
2282{
2283 return refcount_read(r: &sk->sk_wmem_alloc) - 1;
2284}
2285
2286/**
2287 * sk_rmem_alloc_get - returns read allocations
2288 * @sk: socket
2289 *
2290 * Return: sk_rmem_alloc
2291 */
2292static inline int sk_rmem_alloc_get(const struct sock *sk)
2293{
2294 return atomic_read(v: &sk->sk_rmem_alloc);
2295}
2296
2297/**
2298 * sk_has_allocations - check if allocations are outstanding
2299 * @sk: socket
2300 *
2301 * Return: true if socket has write or read allocations
2302 */
2303static inline bool sk_has_allocations(const struct sock *sk)
2304{
2305 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
2306}
2307
2308/**
2309 * skwq_has_sleeper - check if there are any waiting processes
2310 * @wq: struct socket_wq
2311 *
2312 * Return: true if socket_wq has waiting processes
2313 *
2314 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory
2315 * barrier call. They were added due to the race found within the tcp code.
2316 *
2317 * Consider following tcp code paths::
2318 *
2319 * CPU1 CPU2
2320 * sys_select receive packet
2321 * ... ...
2322 * __add_wait_queue update tp->rcv_nxt
2323 * ... ...
2324 * tp->rcv_nxt check sock_def_readable
2325 * ... {
2326 * schedule rcu_read_lock();
2327 * wq = rcu_dereference(sk->sk_wq);
2328 * if (wq && waitqueue_active(&wq->wait))
2329 * wake_up_interruptible(&wq->wait)
2330 * ...
2331 * }
2332 *
2333 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
2334 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1
2335 * could then endup calling schedule and sleep forever if there are no more
2336 * data on the socket.
2337 *
2338 */
2339static inline bool skwq_has_sleeper(struct socket_wq *wq)
2340{
2341 return wq && wq_has_sleeper(wq_head: &wq->wait);
2342}
2343
2344/**
2345 * sock_poll_wait - place memory barrier behind the poll_wait call.
2346 * @filp: file
2347 * @sock: socket to wait on
2348 * @p: poll_table
2349 *
2350 * See the comments in the wq_has_sleeper function.
2351 */
2352static inline void sock_poll_wait(struct file *filp, struct socket *sock,
2353 poll_table *p)
2354{
2355 if (!poll_does_not_wait(p)) {
2356 poll_wait(filp, wait_address: &sock->wq.wait, p);
2357 /* We need to be sure we are in sync with the
2358 * socket flags modification.
2359 *
2360 * This memory barrier is paired in the wq_has_sleeper.
2361 */
2362 smp_mb();
2363 }
2364}
2365
2366static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk)
2367{
2368 /* This pairs with WRITE_ONCE() in sk_set_txhash() */
2369 u32 txhash = READ_ONCE(sk->sk_txhash);
2370
2371 if (txhash) {
2372 skb->l4_hash = 1;
2373 skb->hash = txhash;
2374 }
2375}
2376
2377void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);
2378
2379/*
2380 * Queue a received datagram if it will fit. Stream and sequenced
2381 * protocols can't normally use this as they need to fit buffers in
2382 * and play with them.
2383 *
2384 * Inlined as it's very short and called for pretty much every
2385 * packet ever received.
2386 */
2387static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
2388{
2389 skb_orphan(skb);
2390 skb->sk = sk;
2391 skb->destructor = sock_rfree;
2392 atomic_add(i: skb->truesize, v: &sk->sk_rmem_alloc);
2393 sk_mem_charge(sk, size: skb->truesize);
2394}
2395
2396static inline __must_check bool skb_set_owner_sk_safe(struct sk_buff *skb, struct sock *sk)
2397{
2398 if (sk && refcount_inc_not_zero(r: &sk->sk_refcnt)) {
2399 skb_orphan(skb);
2400 skb->destructor = sock_efree;
2401 skb->sk = sk;
2402 return true;
2403 }
2404 return false;
2405}
2406
2407static inline struct sk_buff *skb_clone_and_charge_r(struct sk_buff *skb, struct sock *sk)
2408{
2409 skb = skb_clone(skb, priority: sk_gfp_mask(sk, GFP_ATOMIC));
2410 if (skb) {
2411 if (sk_rmem_schedule(sk, skb, size: skb->truesize)) {
2412 skb_set_owner_r(skb, sk);
2413 return skb;
2414 }
2415 __kfree_skb(skb);
2416 }
2417 return NULL;
2418}
2419
2420static inline void skb_prepare_for_gro(struct sk_buff *skb)
2421{
2422 if (skb->destructor != sock_wfree) {
2423 skb_orphan(skb);
2424 return;
2425 }
2426 skb->slow_gro = 1;
2427}
2428
2429void sk_reset_timer(struct sock *sk, struct timer_list *timer,
2430 unsigned long expires);
2431
2432void sk_stop_timer(struct sock *sk, struct timer_list *timer);
2433
2434void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer);
2435
2436int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue,
2437 struct sk_buff *skb, unsigned int flags,
2438 void (*destructor)(struct sock *sk,
2439 struct sk_buff *skb));
2440int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2441
2442int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb,
2443 enum skb_drop_reason *reason);
2444
2445static inline int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
2446{
2447 return sock_queue_rcv_skb_reason(sk, skb, NULL);
2448}
2449
2450int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2451struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
2452
2453/*
2454 * Recover an error report and clear atomically
2455 */
2456
2457static inline int sock_error(struct sock *sk)
2458{
2459 int err;
2460
2461 /* Avoid an atomic operation for the common case.
2462 * This is racy since another cpu/thread can change sk_err under us.
2463 */
2464 if (likely(data_race(!sk->sk_err)))
2465 return 0;
2466
2467 err = xchg(&sk->sk_err, 0);
2468 return -err;
2469}
2470
2471void sk_error_report(struct sock *sk);
2472
2473static inline unsigned long sock_wspace(struct sock *sk)
2474{
2475 int amt = 0;
2476
2477 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2478 amt = sk->sk_sndbuf - refcount_read(r: &sk->sk_wmem_alloc);
2479 if (amt < 0)
2480 amt = 0;
2481 }
2482 return amt;
2483}
2484
2485/* Note:
2486 * We use sk->sk_wq_raw, from contexts knowing this
2487 * pointer is not NULL and cannot disappear/change.
2488 */
2489static inline void sk_set_bit(int nr, struct sock *sk)
2490{
2491 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2492 !sock_flag(sk, flag: SOCK_FASYNC))
2493 return;
2494
2495 set_bit(nr, addr: &sk->sk_wq_raw->flags);
2496}
2497
2498static inline void sk_clear_bit(int nr, struct sock *sk)
2499{
2500 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2501 !sock_flag(sk, flag: SOCK_FASYNC))
2502 return;
2503
2504 clear_bit(nr, addr: &sk->sk_wq_raw->flags);
2505}
2506
2507static inline void sk_wake_async(const struct sock *sk, int how, int band)
2508{
2509 if (sock_flag(sk, flag: SOCK_FASYNC)) {
2510 rcu_read_lock();
2511 sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2512 rcu_read_unlock();
2513 }
2514}
2515
2516/* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2517 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2518 * Note: for send buffers, TCP works better if we can build two skbs at
2519 * minimum.
2520 */
2521#define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2522
2523#define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2)
2524#define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE
2525
2526static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2527{
2528 u32 val;
2529
2530 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)
2531 return;
2532
2533 val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2534 val = max_t(u32, val, sk_unused_reserved_mem(sk));
2535
2536 WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF));
2537}
2538
2539/**
2540 * sk_page_frag - return an appropriate page_frag
2541 * @sk: socket
2542 *
2543 * Use the per task page_frag instead of the per socket one for
2544 * optimization when we know that we're in process context and own
2545 * everything that's associated with %current.
2546 *
2547 * Both direct reclaim and page faults can nest inside other
2548 * socket operations and end up recursing into sk_page_frag()
2549 * while it's already in use: explicitly avoid task page_frag
2550 * when users disable sk_use_task_frag.
2551 *
2552 * Return: a per task page_frag if context allows that,
2553 * otherwise a per socket one.
2554 */
2555static inline struct page_frag *sk_page_frag(struct sock *sk)
2556{
2557 if (sk->sk_use_task_frag)
2558 return &current->task_frag;
2559
2560 return &sk->sk_frag;
2561}
2562
2563bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2564
2565/*
2566 * Default write policy as shown to user space via poll/select/SIGIO
2567 */
2568static inline bool sock_writeable(const struct sock *sk)
2569{
2570 return refcount_read(r: &sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1);
2571}
2572
2573static inline gfp_t gfp_any(void)
2574{
2575 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2576}
2577
2578static inline gfp_t gfp_memcg_charge(void)
2579{
2580 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2581}
2582
2583static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2584{
2585 return noblock ? 0 : sk->sk_rcvtimeo;
2586}
2587
2588static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2589{
2590 return noblock ? 0 : sk->sk_sndtimeo;
2591}
2592
2593static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2594{
2595 int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len);
2596
2597 return v ?: 1;
2598}
2599
2600/* Alas, with timeout socket operations are not restartable.
2601 * Compare this to poll().
2602 */
2603static inline int sock_intr_errno(long timeo)
2604{
2605 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2606}
2607
2608struct sock_skb_cb {
2609 u32 dropcount;
2610};
2611
2612/* Store sock_skb_cb at the end of skb->cb[] so protocol families
2613 * using skb->cb[] would keep using it directly and utilize its
2614 * alignement guarantee.
2615 */
2616#define SOCK_SKB_CB_OFFSET ((sizeof_field(struct sk_buff, cb) - \
2617 sizeof(struct sock_skb_cb)))
2618
2619#define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
2620 SOCK_SKB_CB_OFFSET))
2621
2622#define sock_skb_cb_check_size(size) \
2623 BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
2624
2625static inline void
2626sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
2627{
2628 SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, flag: SOCK_RXQ_OVFL) ?
2629 atomic_read(v: &sk->sk_drops) : 0;
2630}
2631
2632static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb)
2633{
2634 int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs);
2635
2636 atomic_add(i: segs, v: &sk->sk_drops);
2637}
2638
2639static inline ktime_t sock_read_timestamp(struct sock *sk)
2640{
2641#if BITS_PER_LONG==32
2642 unsigned int seq;
2643 ktime_t kt;
2644
2645 do {
2646 seq = read_seqbegin(&sk->sk_stamp_seq);
2647 kt = sk->sk_stamp;
2648 } while (read_seqretry(&sk->sk_stamp_seq, seq));
2649
2650 return kt;
2651#else
2652 return READ_ONCE(sk->sk_stamp);
2653#endif
2654}
2655
2656static inline void sock_write_timestamp(struct sock *sk, ktime_t kt)
2657{
2658#if BITS_PER_LONG==32
2659 write_seqlock(&sk->sk_stamp_seq);
2660 sk->sk_stamp = kt;
2661 write_sequnlock(&sk->sk_stamp_seq);
2662#else
2663 WRITE_ONCE(sk->sk_stamp, kt);
2664#endif
2665}
2666
2667void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2668 struct sk_buff *skb);
2669void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2670 struct sk_buff *skb);
2671
2672static inline void
2673sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2674{
2675 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2676 u32 tsflags = READ_ONCE(sk->sk_tsflags);
2677 ktime_t kt = skb->tstamp;
2678 /*
2679 * generate control messages if
2680 * - receive time stamping in software requested
2681 * - software time stamp available and wanted
2682 * - hardware time stamps available and wanted
2683 */
2684 if (sock_flag(sk, flag: SOCK_RCVTSTAMP) ||
2685 (tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
2686 (kt && tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
2687 (hwtstamps->hwtstamp &&
2688 (tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
2689 __sock_recv_timestamp(msg, sk, skb);
2690 else
2691 sock_write_timestamp(sk, kt);
2692
2693 if (sock_flag(sk, flag: SOCK_WIFI_STATUS) && skb_wifi_acked_valid(skb))
2694 __sock_recv_wifi_status(msg, sk, skb);
2695}
2696
2697void __sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
2698 struct sk_buff *skb);
2699
2700#define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC)
2701static inline void sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
2702 struct sk_buff *skb)
2703{
2704#define FLAGS_RECV_CMSGS ((1UL << SOCK_RXQ_OVFL) | \
2705 (1UL << SOCK_RCVTSTAMP) | \
2706 (1UL << SOCK_RCVMARK))
2707#define TSFLAGS_ANY (SOF_TIMESTAMPING_SOFTWARE | \
2708 SOF_TIMESTAMPING_RAW_HARDWARE)
2709
2710 if (sk->sk_flags & FLAGS_RECV_CMSGS ||
2711 READ_ONCE(sk->sk_tsflags) & TSFLAGS_ANY)
2712 __sock_recv_cmsgs(msg, sk, skb);
2713 else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP)))
2714 sock_write_timestamp(sk, kt: skb->tstamp);
2715 else if (unlikely(sock_read_timestamp(sk) == SK_DEFAULT_STAMP))
2716 sock_write_timestamp(sk, kt: 0);
2717}
2718
2719void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags);
2720
2721/**
2722 * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2723 * @sk: socket sending this packet
2724 * @tsflags: timestamping flags to use
2725 * @tx_flags: completed with instructions for time stamping
2726 * @tskey: filled in with next sk_tskey (not for TCP, which uses seqno)
2727 *
2728 * Note: callers should take care of initial ``*tx_flags`` value (usually 0)
2729 */
2730static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2731 __u8 *tx_flags, __u32 *tskey)
2732{
2733 if (unlikely(tsflags)) {
2734 __sock_tx_timestamp(tsflags, tx_flags);
2735 if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey &&
2736 tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK)
2737 *tskey = atomic_inc_return(v: &sk->sk_tskey) - 1;
2738 }
2739 if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
2740 *tx_flags |= SKBTX_WIFI_STATUS;
2741}
2742
2743static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2744 __u8 *tx_flags)
2745{
2746 _sock_tx_timestamp(sk, tsflags, tx_flags, NULL);
2747}
2748
2749static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags)
2750{
2751 _sock_tx_timestamp(sk: skb->sk, tsflags, tx_flags: &skb_shinfo(skb)->tx_flags,
2752 tskey: &skb_shinfo(skb)->tskey);
2753}
2754
2755static inline bool sk_is_inet(const struct sock *sk)
2756{
2757 int family = READ_ONCE(sk->sk_family);
2758
2759 return family == AF_INET || family == AF_INET6;
2760}
2761
2762static inline bool sk_is_tcp(const struct sock *sk)
2763{
2764 return sk_is_inet(sk) &&
2765 sk->sk_type == SOCK_STREAM &&
2766 sk->sk_protocol == IPPROTO_TCP;
2767}
2768
2769static inline bool sk_is_udp(const struct sock *sk)
2770{
2771 return sk_is_inet(sk) &&
2772 sk->sk_type == SOCK_DGRAM &&
2773 sk->sk_protocol == IPPROTO_UDP;
2774}
2775
2776static inline bool sk_is_stream_unix(const struct sock *sk)
2777{
2778 return sk->sk_family == AF_UNIX && sk->sk_type == SOCK_STREAM;
2779}
2780
2781/**
2782 * sk_eat_skb - Release a skb if it is no longer needed
2783 * @sk: socket to eat this skb from
2784 * @skb: socket buffer to eat
2785 *
2786 * This routine must be called with interrupts disabled or with the socket
2787 * locked so that the sk_buff queue operation is ok.
2788*/
2789static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
2790{
2791 __skb_unlink(skb, list: &sk->sk_receive_queue);
2792 __kfree_skb(skb);
2793}
2794
2795static inline bool
2796skb_sk_is_prefetched(struct sk_buff *skb)
2797{
2798#ifdef CONFIG_INET
2799 return skb->destructor == sock_pfree;
2800#else
2801 return false;
2802#endif /* CONFIG_INET */
2803}
2804
2805/* This helper checks if a socket is a full socket,
2806 * ie _not_ a timewait or request socket.
2807 */
2808static inline bool sk_fullsock(const struct sock *sk)
2809{
2810 return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
2811}
2812
2813static inline bool
2814sk_is_refcounted(struct sock *sk)
2815{
2816 /* Only full sockets have sk->sk_flags. */
2817 return !sk_fullsock(sk) || !sock_flag(sk, flag: SOCK_RCU_FREE);
2818}
2819
2820/* Checks if this SKB belongs to an HW offloaded socket
2821 * and whether any SW fallbacks are required based on dev.
2822 * Check decrypted mark in case skb_orphan() cleared socket.
2823 */
2824static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb,
2825 struct net_device *dev)
2826{
2827#ifdef CONFIG_SOCK_VALIDATE_XMIT
2828 struct sock *sk = skb->sk;
2829
2830 if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) {
2831 skb = sk->sk_validate_xmit_skb(sk, dev, skb);
2832#ifdef CONFIG_TLS_DEVICE
2833 } else if (unlikely(skb->decrypted)) {
2834 pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n");
2835 kfree_skb(skb);
2836 skb = NULL;
2837#endif
2838 }
2839#endif
2840
2841 return skb;
2842}
2843
2844/* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
2845 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
2846 */
2847static inline bool sk_listener(const struct sock *sk)
2848{
2849 return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
2850}
2851
2852void sock_enable_timestamp(struct sock *sk, enum sock_flags flag);
2853int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
2854 int type);
2855
2856bool sk_ns_capable(const struct sock *sk,
2857 struct user_namespace *user_ns, int cap);
2858bool sk_capable(const struct sock *sk, int cap);
2859bool sk_net_capable(const struct sock *sk, int cap);
2860
2861void sk_get_meminfo(const struct sock *sk, u32 *meminfo);
2862
2863/* Take into consideration the size of the struct sk_buff overhead in the
2864 * determination of these values, since that is non-constant across
2865 * platforms. This makes socket queueing behavior and performance
2866 * not depend upon such differences.
2867 */
2868#define _SK_MEM_PACKETS 256
2869#define _SK_MEM_OVERHEAD SKB_TRUESIZE(256)
2870#define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2871#define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2872
2873extern __u32 sysctl_wmem_max;
2874extern __u32 sysctl_rmem_max;
2875
2876extern int sysctl_tstamp_allow_data;
2877
2878extern __u32 sysctl_wmem_default;
2879extern __u32 sysctl_rmem_default;
2880
2881#define SKB_FRAG_PAGE_ORDER get_order(32768)
2882DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2883
2884static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto)
2885{
2886 /* Does this proto have per netns sysctl_wmem ? */
2887 if (proto->sysctl_wmem_offset)
2888 return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset));
2889
2890 return READ_ONCE(*proto->sysctl_wmem);
2891}
2892
2893static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto)
2894{
2895 /* Does this proto have per netns sysctl_rmem ? */
2896 if (proto->sysctl_rmem_offset)
2897 return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset));
2898
2899 return READ_ONCE(*proto->sysctl_rmem);
2900}
2901
2902/* Default TCP Small queue budget is ~1 ms of data (1sec >> 10)
2903 * Some wifi drivers need to tweak it to get more chunks.
2904 * They can use this helper from their ndo_start_xmit()
2905 */
2906static inline void sk_pacing_shift_update(struct sock *sk, int val)
2907{
2908 if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val)
2909 return;
2910 WRITE_ONCE(sk->sk_pacing_shift, val);
2911}
2912
2913/* if a socket is bound to a device, check that the given device
2914 * index is either the same or that the socket is bound to an L3
2915 * master device and the given device index is also enslaved to
2916 * that L3 master
2917 */
2918static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif)
2919{
2920 int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
2921 int mdif;
2922
2923 if (!bound_dev_if || bound_dev_if == dif)
2924 return true;
2925
2926 mdif = l3mdev_master_ifindex_by_index(net: sock_net(sk), ifindex: dif);
2927 if (mdif && mdif == bound_dev_if)
2928 return true;
2929
2930 return false;
2931}
2932
2933void sock_def_readable(struct sock *sk);
2934
2935int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk);
2936void sock_set_timestamp(struct sock *sk, int optname, bool valbool);
2937int sock_set_timestamping(struct sock *sk, int optname,
2938 struct so_timestamping timestamping);
2939
2940void sock_enable_timestamps(struct sock *sk);
2941void sock_no_linger(struct sock *sk);
2942void sock_set_keepalive(struct sock *sk);
2943void sock_set_priority(struct sock *sk, u32 priority);
2944void sock_set_rcvbuf(struct sock *sk, int val);
2945void sock_set_mark(struct sock *sk, u32 val);
2946void sock_set_reuseaddr(struct sock *sk);
2947void sock_set_reuseport(struct sock *sk);
2948void sock_set_sndtimeo(struct sock *sk, s64 secs);
2949
2950int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len);
2951
2952int sock_get_timeout(long timeo, void *optval, bool old_timeval);
2953int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
2954 sockptr_t optval, int optlen, bool old_timeval);
2955
2956int sock_ioctl_inout(struct sock *sk, unsigned int cmd,
2957 void __user *arg, void *karg, size_t size);
2958int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg);
2959static inline bool sk_is_readable(struct sock *sk)
2960{
2961 if (sk->sk_prot->sock_is_readable)
2962 return sk->sk_prot->sock_is_readable(sk);
2963 return false;
2964}
2965#endif /* _SOCK_H */
2966

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