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1/*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * Definitions for the AF_INET socket handler.
7 *
8 * Version: @(#)sock.h 1.0.4 05/13/93
9 *
10 * Authors: Ross Biro
11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 * Corey Minyard <wf-rch!minyard@relay.EU.net>
13 * Florian La Roche <flla@stud.uni-sb.de>
14 *
15 * Fixes:
16 * Alan Cox : Volatiles in skbuff pointers. See
17 * skbuff comments. May be overdone,
18 * better to prove they can be removed
19 * than the reverse.
20 * Alan Cox : Added a zapped field for tcp to note
21 * a socket is reset and must stay shut up
22 * Alan Cox : New fields for options
23 * Pauline Middelink : identd support
24 * Alan Cox : Eliminate low level recv/recvfrom
25 * David S. Miller : New socket lookup architecture.
26 * Steve Whitehouse: Default routines for sock_ops
27 * Arnaldo C. Melo : removed net_pinfo, tp_pinfo and made
28 * protinfo be just a void pointer, as the
29 * protocol specific parts were moved to
30 * respective headers and ipv4/v6, etc now
31 * use private slabcaches for its socks
32 * Pedro Hortas : New flags field for socket options
33 *
34 *
35 * This program is free software; you can redistribute it and/or
36 * modify it under the terms of the GNU General Public License
37 * as published by the Free Software Foundation; either version
38 * 2 of the License, or (at your option) any later version.
39 */
40#ifndef _SOCK_H
41#define _SOCK_H
42
43#include <linux/hardirq.h>
44#include <linux/kernel.h>
45#include <linux/list.h>
46#include <linux/list_nulls.h>
47#include <linux/timer.h>
48#include <linux/cache.h>
49#include <linux/module.h>
50#include <linux/lockdep.h>
51#include <linux/netdevice.h>
52#include <linux/skbuff.h> /* struct sk_buff */
53#include <linux/mm.h>
54#include <linux/security.h>
55#include <linux/slab.h>
56#include <linux/uaccess.h>
57
58#include <linux/filter.h>
59#include <linux/rculist_nulls.h>
60#include <linux/poll.h>
61
62#include <linux/atomic.h>
63#include <net/dst.h>
64#include <net/checksum.h>
65
66/*
67 * This structure really needs to be cleaned up.
68 * Most of it is for TCP, and not used by any of
69 * the other protocols.
70 */
71
72/* Define this to get the SOCK_DBG debugging facility. */
73#define SOCK_DEBUGGING
74#ifdef SOCK_DEBUGGING
75#define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
76 printk(KERN_DEBUG msg); } while (0)
77#else
78/* Validate arguments and do nothing */
79static inline void __attribute__ ((format (printf, 2, 3)))
80SOCK_DEBUG(struct sock *sk, const char *msg, ...)
81{
82}
83#endif
84
85/* This is the per-socket lock. The spinlock provides a synchronization
86 * between user contexts and software interrupt processing, whereas the
87 * mini-semaphore synchronizes multiple users amongst themselves.
88 */
89typedef struct {
90 spinlock_t slock;
91 int owned;
92 wait_queue_head_t wq;
93 /*
94 * We express the mutex-alike socket_lock semantics
95 * to the lock validator by explicitly managing
96 * the slock as a lock variant (in addition to
97 * the slock itself):
98 */
99#ifdef CONFIG_DEBUG_LOCK_ALLOC
100 struct lockdep_map dep_map;
101#endif
102} socket_lock_t;
103
104struct sock;
105struct proto;
106struct net;
107
108/**
109 * struct sock_common - minimal network layer representation of sockets
110 * @skc_daddr: Foreign IPv4 addr
111 * @skc_rcv_saddr: Bound local IPv4 addr
112 * @skc_hash: hash value used with various protocol lookup tables
113 * @skc_u16hashes: two u16 hash values used by UDP lookup tables
114 * @skc_family: network address family
115 * @skc_state: Connection state
116 * @skc_reuse: %SO_REUSEADDR setting
117 * @skc_bound_dev_if: bound device index if != 0
118 * @skc_bind_node: bind hash linkage for various protocol lookup tables
119 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
120 * @skc_prot: protocol handlers inside a network family
121 * @skc_net: reference to the network namespace of this socket
122 * @skc_node: main hash linkage for various protocol lookup tables
123 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
124 * @skc_tx_queue_mapping: tx queue number for this connection
125 * @skc_refcnt: reference count
126 *
127 * This is the minimal network layer representation of sockets, the header
128 * for struct sock and struct inet_timewait_sock.
129 */
130struct sock_common {
131 /* skc_daddr and skc_rcv_saddr must be grouped :
132 * cf INET_MATCH() and INET_TW_MATCH()
133 */
134 __be32 skc_daddr;
135 __be32 skc_rcv_saddr;
136
137 union {
138 unsigned int skc_hash;
139 __u16 skc_u16hashes[2];
140 };
141 unsigned short skc_family;
142 volatile unsigned char skc_state;
143 unsigned char skc_reuse;
144 int skc_bound_dev_if;
145 union {
146 struct hlist_node skc_bind_node;
147 struct hlist_nulls_node skc_portaddr_node;
148 };
149 struct proto *skc_prot;
150#ifdef CONFIG_NET_NS
151 struct net *skc_net;
152#endif
153 /*
154 * fields between dontcopy_begin/dontcopy_end
155 * are not copied in sock_copy()
156 */
157 /* private: */
158 int skc_dontcopy_begin[0];
159 /* public: */
160 union {
161 struct hlist_node skc_node;
162 struct hlist_nulls_node skc_nulls_node;
163 };
164 int skc_tx_queue_mapping;
165 atomic_t skc_refcnt;
166 /* private: */
167 int skc_dontcopy_end[0];
168 /* public: */
169};
170
171/**
172 * struct sock - network layer representation of sockets
173 * @__sk_common: shared layout with inet_timewait_sock
174 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
175 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
176 * @sk_lock: synchronizer
177 * @sk_rcvbuf: size of receive buffer in bytes
178 * @sk_wq: sock wait queue and async head
179 * @sk_dst_cache: destination cache
180 * @sk_dst_lock: destination cache lock
181 * @sk_policy: flow policy
182 * @sk_receive_queue: incoming packets
183 * @sk_wmem_alloc: transmit queue bytes committed
184 * @sk_write_queue: Packet sending queue
185 * @sk_async_wait_queue: DMA copied packets
186 * @sk_omem_alloc: "o" is "option" or "other"
187 * @sk_wmem_queued: persistent queue size
188 * @sk_forward_alloc: space allocated forward
189 * @sk_allocation: allocation mode
190 * @sk_sndbuf: size of send buffer in bytes
191 * @sk_flags: %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
192 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings
193 * @sk_no_check: %SO_NO_CHECK setting, wether or not checkup packets
194 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
195 * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK)
196 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
197 * @sk_gso_max_size: Maximum GSO segment size to build
198 * @sk_lingertime: %SO_LINGER l_linger setting
199 * @sk_backlog: always used with the per-socket spinlock held
200 * @sk_callback_lock: used with the callbacks in the end of this struct
201 * @sk_error_queue: rarely used
202 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
203 * IPV6_ADDRFORM for instance)
204 * @sk_err: last error
205 * @sk_err_soft: errors that don't cause failure but are the cause of a
206 * persistent failure not just 'timed out'
207 * @sk_drops: raw/udp drops counter
208 * @sk_ack_backlog: current listen backlog
209 * @sk_max_ack_backlog: listen backlog set in listen()
210 * @sk_priority: %SO_PRIORITY setting
211 * @sk_type: socket type (%SOCK_STREAM, etc)
212 * @sk_protocol: which protocol this socket belongs in this network family
213 * @sk_peer_pid: &struct pid for this socket's peer
214 * @sk_peer_cred: %SO_PEERCRED setting
215 * @sk_rcvlowat: %SO_RCVLOWAT setting
216 * @sk_rcvtimeo: %SO_RCVTIMEO setting
217 * @sk_sndtimeo: %SO_SNDTIMEO setting
218 * @sk_rxhash: flow hash received from netif layer
219 * @sk_filter: socket filtering instructions
220 * @sk_protinfo: private area, net family specific, when not using slab
221 * @sk_timer: sock cleanup timer
222 * @sk_stamp: time stamp of last packet received
223 * @sk_socket: Identd and reporting IO signals
224 * @sk_user_data: RPC layer private data
225 * @sk_sndmsg_page: cached page for sendmsg
226 * @sk_sndmsg_off: cached offset for sendmsg
227 * @sk_send_head: front of stuff to transmit
228 * @sk_security: used by security modules
229 * @sk_mark: generic packet mark
230 * @sk_classid: this socket's cgroup classid
231 * @sk_write_pending: a write to stream socket waits to start
232 * @sk_state_change: callback to indicate change in the state of the sock
233 * @sk_data_ready: callback to indicate there is data to be processed
234 * @sk_write_space: callback to indicate there is bf sending space available
235 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
236 * @sk_backlog_rcv: callback to process the backlog
237 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
238 */
239struct sock {
240 /*
241 * Now struct inet_timewait_sock also uses sock_common, so please just
242 * don't add nothing before this first member (__sk_common) --acme
243 */
244 struct sock_common __sk_common;
245#define sk_node __sk_common.skc_node
246#define sk_nulls_node __sk_common.skc_nulls_node
247#define sk_refcnt __sk_common.skc_refcnt
248#define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping
249
250#define sk_dontcopy_begin __sk_common.skc_dontcopy_begin
251#define sk_dontcopy_end __sk_common.skc_dontcopy_end
252#define sk_hash __sk_common.skc_hash
253#define sk_family __sk_common.skc_family
254#define sk_state __sk_common.skc_state
255#define sk_reuse __sk_common.skc_reuse
256#define sk_bound_dev_if __sk_common.skc_bound_dev_if
257#define sk_bind_node __sk_common.skc_bind_node
258#define sk_prot __sk_common.skc_prot
259#define sk_net __sk_common.skc_net
260 socket_lock_t sk_lock;
261 struct sk_buff_head sk_receive_queue;
262 /*
263 * The backlog queue is special, it is always used with
264 * the per-socket spinlock held and requires low latency
265 * access. Therefore we special case it's implementation.
266 * Note : rmem_alloc is in this structure to fill a hole
267 * on 64bit arches, not because its logically part of
268 * backlog.
269 */
270 struct {
271 atomic_t rmem_alloc;
272 int len;
273 struct sk_buff *head;
274 struct sk_buff *tail;
275 } sk_backlog;
276#define sk_rmem_alloc sk_backlog.rmem_alloc
277 int sk_forward_alloc;
278#ifdef CONFIG_RPS
279 __u32 sk_rxhash;
280#endif
281 atomic_t sk_drops;
282 int sk_rcvbuf;
283
284 struct sk_filter __rcu *sk_filter;
285 struct socket_wq __rcu *sk_wq;
286
287#ifdef CONFIG_NET_DMA
288 struct sk_buff_head sk_async_wait_queue;
289#endif
290
291#ifdef CONFIG_XFRM
292 struct xfrm_policy *sk_policy[2];
293#endif
294 unsigned long sk_flags;
295 struct dst_entry *sk_dst_cache;
296 spinlock_t sk_dst_lock;
297 atomic_t sk_wmem_alloc;
298 atomic_t sk_omem_alloc;
299 int sk_sndbuf;
300 struct sk_buff_head sk_write_queue;
301 kmemcheck_bitfield_begin(flags);
302 unsigned int sk_shutdown : 2,
303 sk_no_check : 2,
304 sk_userlocks : 4,
305 sk_protocol : 8,
306 sk_type : 16;
307 kmemcheck_bitfield_end(flags);
308 int sk_wmem_queued;
309 gfp_t sk_allocation;
310 int sk_route_caps;
311 int sk_route_nocaps;
312 int sk_gso_type;
313 unsigned int sk_gso_max_size;
314 int sk_rcvlowat;
315 unsigned long sk_lingertime;
316 struct sk_buff_head sk_error_queue;
317 struct proto *sk_prot_creator;
318 rwlock_t sk_callback_lock;
319 int sk_err,
320 sk_err_soft;
321 unsigned short sk_ack_backlog;
322 unsigned short sk_max_ack_backlog;
323 __u32 sk_priority;
324 struct pid *sk_peer_pid;
325 const struct cred *sk_peer_cred;
326 long sk_rcvtimeo;
327 long sk_sndtimeo;
328 void *sk_protinfo;
329 struct timer_list sk_timer;
330 ktime_t sk_stamp;
331 struct socket *sk_socket;
332 void *sk_user_data;
333 struct page *sk_sndmsg_page;
334 struct sk_buff *sk_send_head;
335 __u32 sk_sndmsg_off;
336 int sk_write_pending;
337#ifdef CONFIG_SECURITY
338 void *sk_security;
339#endif
340 __u32 sk_mark;
341 u32 sk_classid;
342 void (*sk_state_change)(struct sock *sk);
343 void (*sk_data_ready)(struct sock *sk, int bytes);
344 void (*sk_write_space)(struct sock *sk);
345 void (*sk_error_report)(struct sock *sk);
346 int (*sk_backlog_rcv)(struct sock *sk,
347 struct sk_buff *skb);
348 void (*sk_destruct)(struct sock *sk);
349};
350
351/*
352 * Hashed lists helper routines
353 */
354static inline struct sock *sk_entry(const struct hlist_node *node)
355{
356 return hlist_entry(node, struct sock, sk_node);
357}
358
359static inline struct sock *__sk_head(const struct hlist_head *head)
360{
361 return hlist_entry(head->first, struct sock, sk_node);
362}
363
364static inline struct sock *sk_head(const struct hlist_head *head)
365{
366 return hlist_empty(head) ? NULL : __sk_head(head);
367}
368
369static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
370{
371 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
372}
373
374static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
375{
376 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
377}
378
379static inline struct sock *sk_next(const struct sock *sk)
380{
381 return sk->sk_node.next ?
382 hlist_entry(sk->sk_node.next, struct sock, sk_node) : NULL;
383}
384
385static inline struct sock *sk_nulls_next(const struct sock *sk)
386{
387 return (!is_a_nulls(sk->sk_nulls_node.next)) ?
388 hlist_nulls_entry(sk->sk_nulls_node.next,
389 struct sock, sk_nulls_node) :
390 NULL;
391}
392
393static inline int sk_unhashed(const struct sock *sk)
394{
395 return hlist_unhashed(&sk->sk_node);
396}
397
398static inline int sk_hashed(const struct sock *sk)
399{
400 return !sk_unhashed(sk);
401}
402
403static __inline__ void sk_node_init(struct hlist_node *node)
404{
405 node->pprev = NULL;
406}
407
408static __inline__ void sk_nulls_node_init(struct hlist_nulls_node *node)
409{
410 node->pprev = NULL;
411}
412
413static __inline__ void __sk_del_node(struct sock *sk)
414{
415 __hlist_del(&sk->sk_node);
416}
417
418/* NB: equivalent to hlist_del_init_rcu */
419static __inline__ int __sk_del_node_init(struct sock *sk)
420{
421 if (sk_hashed(sk)) {
422 __sk_del_node(sk);
423 sk_node_init(&sk->sk_node);
424 return 1;
425 }
426 return 0;
427}
428
429/* Grab socket reference count. This operation is valid only
430 when sk is ALREADY grabbed f.e. it is found in hash table
431 or a list and the lookup is made under lock preventing hash table
432 modifications.
433 */
434
435static inline void sock_hold(struct sock *sk)
436{
437 atomic_inc(&sk->sk_refcnt);
438}
439
440/* Ungrab socket in the context, which assumes that socket refcnt
441 cannot hit zero, f.e. it is true in context of any socketcall.
442 */
443static inline void __sock_put(struct sock *sk)
444{
445 atomic_dec(&sk->sk_refcnt);
446}
447
448static __inline__ int sk_del_node_init(struct sock *sk)
449{
450 int rc = __sk_del_node_init(sk);
451
452 if (rc) {
453 /* paranoid for a while -acme */
454 WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
455 __sock_put(sk);
456 }
457 return rc;
458}
459#define sk_del_node_init_rcu(sk) sk_del_node_init(sk)
460
461static __inline__ int __sk_nulls_del_node_init_rcu(struct sock *sk)
462{
463 if (sk_hashed(sk)) {
464 hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
465 return 1;
466 }
467 return 0;
468}
469
470static __inline__ int sk_nulls_del_node_init_rcu(struct sock *sk)
471{
472 int rc = __sk_nulls_del_node_init_rcu(sk);
473
474 if (rc) {
475 /* paranoid for a while -acme */
476 WARN_ON(atomic_read(&sk->sk_refcnt) == 1);
477 __sock_put(sk);
478 }
479 return rc;
480}
481
482static __inline__ void __sk_add_node(struct sock *sk, struct hlist_head *list)
483{
484 hlist_add_head(&sk->sk_node, list);
485}
486
487static __inline__ void sk_add_node(struct sock *sk, struct hlist_head *list)
488{
489 sock_hold(sk);
490 __sk_add_node(sk, list);
491}
492
493static __inline__ void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
494{
495 sock_hold(sk);
496 hlist_add_head_rcu(&sk->sk_node, list);
497}
498
499static __inline__ void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
500{
501 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
502}
503
504static __inline__ void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
505{
506 sock_hold(sk);
507 __sk_nulls_add_node_rcu(sk, list);
508}
509
510static __inline__ void __sk_del_bind_node(struct sock *sk)
511{
512 __hlist_del(&sk->sk_bind_node);
513}
514
515static __inline__ void sk_add_bind_node(struct sock *sk,
516 struct hlist_head *list)
517{
518 hlist_add_head(&sk->sk_bind_node, list);
519}
520
521#define sk_for_each(__sk, node, list) \
522 hlist_for_each_entry(__sk, node, list, sk_node)
523#define sk_for_each_rcu(__sk, node, list) \
524 hlist_for_each_entry_rcu(__sk, node, list, sk_node)
525#define sk_nulls_for_each(__sk, node, list) \
526 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
527#define sk_nulls_for_each_rcu(__sk, node, list) \
528 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
529#define sk_for_each_from(__sk, node) \
530 if (__sk && ({ node = &(__sk)->sk_node; 1; })) \
531 hlist_for_each_entry_from(__sk, node, sk_node)
532#define sk_nulls_for_each_from(__sk, node) \
533 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
534 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
535#define sk_for_each_safe(__sk, node, tmp, list) \
536 hlist_for_each_entry_safe(__sk, node, tmp, list, sk_node)
537#define sk_for_each_bound(__sk, node, list) \
538 hlist_for_each_entry(__sk, node, list, sk_bind_node)
539
540/* Sock flags */
541enum sock_flags {
542 SOCK_DEAD,
543 SOCK_DONE,
544 SOCK_URGINLINE,
545 SOCK_KEEPOPEN,
546 SOCK_LINGER,
547 SOCK_DESTROY,
548 SOCK_BROADCAST,
549 SOCK_TIMESTAMP,
550 SOCK_ZAPPED,
551 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
552 SOCK_DBG, /* %SO_DEBUG setting */
553 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
554 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
555 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
556 SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */
557 SOCK_TIMESTAMPING_TX_HARDWARE, /* %SOF_TIMESTAMPING_TX_HARDWARE */
558 SOCK_TIMESTAMPING_TX_SOFTWARE, /* %SOF_TIMESTAMPING_TX_SOFTWARE */
559 SOCK_TIMESTAMPING_RX_HARDWARE, /* %SOF_TIMESTAMPING_RX_HARDWARE */
560 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */
561 SOCK_TIMESTAMPING_SOFTWARE, /* %SOF_TIMESTAMPING_SOFTWARE */
562 SOCK_TIMESTAMPING_RAW_HARDWARE, /* %SOF_TIMESTAMPING_RAW_HARDWARE */
563 SOCK_TIMESTAMPING_SYS_HARDWARE, /* %SOF_TIMESTAMPING_SYS_HARDWARE */
564 SOCK_FASYNC, /* fasync() active */
565 SOCK_RXQ_OVFL,
566 SOCK_ZEROCOPY, /* buffers from userspace */
567};
568
569static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
570{
571 nsk->sk_flags = osk->sk_flags;
572}
573
574static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
575{
576 __set_bit(flag, &sk->sk_flags);
577}
578
579static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
580{
581 __clear_bit(flag, &sk->sk_flags);
582}
583
584static inline int sock_flag(struct sock *sk, enum sock_flags flag)
585{
586 return test_bit(flag, &sk->sk_flags);
587}
588
589static inline void sk_acceptq_removed(struct sock *sk)
590{
591 sk->sk_ack_backlog--;
592}
593
594static inline void sk_acceptq_added(struct sock *sk)
595{
596 sk->sk_ack_backlog++;
597}
598
599static inline int sk_acceptq_is_full(struct sock *sk)
600{
601 return sk->sk_ack_backlog > sk->sk_max_ack_backlog;
602}
603
604/*
605 * Compute minimal free write space needed to queue new packets.
606 */
607static inline int sk_stream_min_wspace(struct sock *sk)
608{
609 return sk->sk_wmem_queued >> 1;
610}
611
612static inline int sk_stream_wspace(struct sock *sk)
613{
614 return sk->sk_sndbuf - sk->sk_wmem_queued;
615}
616
617extern void sk_stream_write_space(struct sock *sk);
618
619static inline int sk_stream_memory_free(struct sock *sk)
620{
621 return sk->sk_wmem_queued < sk->sk_sndbuf;
622}
623
624/* OOB backlog add */
625static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
626{
627 /* dont let skb dst not refcounted, we are going to leave rcu lock */
628 skb_dst_force(skb);
629
630 if (!sk->sk_backlog.tail)
631 sk->sk_backlog.head = skb;
632 else
633 sk->sk_backlog.tail->next = skb;
634
635 sk->sk_backlog.tail = skb;
636 skb->next = NULL;
637}
638
639/*
640 * Take into account size of receive queue and backlog queue
641 */
642static inline bool sk_rcvqueues_full(const struct sock *sk, const struct sk_buff *skb)
643{
644 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
645
646 return qsize + skb->truesize > sk->sk_rcvbuf;
647}
648
649/* The per-socket spinlock must be held here. */
650static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb)
651{
652 if (sk_rcvqueues_full(sk, skb))
653 return -ENOBUFS;
654
655 __sk_add_backlog(sk, skb);
656 sk->sk_backlog.len += skb->truesize;
657 return 0;
658}
659
660static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
661{
662 return sk->sk_backlog_rcv(sk, skb);
663}
664
665static inline void sock_rps_record_flow(const struct sock *sk)
666{
667#ifdef CONFIG_RPS
668 struct rps_sock_flow_table *sock_flow_table;
669
670 rcu_read_lock();
671 sock_flow_table = rcu_dereference(rps_sock_flow_table);
672 rps_record_sock_flow(sock_flow_table, sk->sk_rxhash);
673 rcu_read_unlock();
674#endif
675}
676
677static inline void sock_rps_reset_flow(const struct sock *sk)
678{
679#ifdef CONFIG_RPS
680 struct rps_sock_flow_table *sock_flow_table;
681
682 rcu_read_lock();
683 sock_flow_table = rcu_dereference(rps_sock_flow_table);
684 rps_reset_sock_flow(sock_flow_table, sk->sk_rxhash);
685 rcu_read_unlock();
686#endif
687}
688
689static inline void sock_rps_save_rxhash(struct sock *sk, u32 rxhash)
690{
691#ifdef CONFIG_RPS
692 if (unlikely(sk->sk_rxhash != rxhash)) {
693 sock_rps_reset_flow(sk);
694 sk->sk_rxhash = rxhash;
695 }
696#endif
697}
698
699#define sk_wait_event(__sk, __timeo, __condition) \
700 ({ int __rc; \
701 release_sock(__sk); \
702 __rc = __condition; \
703 if (!__rc) { \
704 *(__timeo) = schedule_timeout(*(__timeo)); \
705 } \
706 lock_sock(__sk); \
707 __rc = __condition; \
708 __rc; \
709 })
710
711extern int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
712extern int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
713extern void sk_stream_wait_close(struct sock *sk, long timeo_p);
714extern int sk_stream_error(struct sock *sk, int flags, int err);
715extern void sk_stream_kill_queues(struct sock *sk);
716
717extern int sk_wait_data(struct sock *sk, long *timeo);
718
719struct request_sock_ops;
720struct timewait_sock_ops;
721struct inet_hashinfo;
722struct raw_hashinfo;
723
724/* Networking protocol blocks we attach to sockets.
725 * socket layer -> transport layer interface
726 * transport -> network interface is defined by struct inet_proto
727 */
728struct proto {
729 void (*close)(struct sock *sk,
730 long timeout);
731 int (*connect)(struct sock *sk,
732 struct sockaddr *uaddr,
733 int addr_len);
734 int (*disconnect)(struct sock *sk, int flags);
735
736 struct sock * (*accept) (struct sock *sk, int flags, int *err);
737
738 int (*ioctl)(struct sock *sk, int cmd,
739 unsigned long arg);
740 int (*init)(struct sock *sk);
741 void (*destroy)(struct sock *sk);
742 void (*shutdown)(struct sock *sk, int how);
743 int (*setsockopt)(struct sock *sk, int level,
744 int optname, char __user *optval,
745 unsigned int optlen);
746 int (*getsockopt)(struct sock *sk, int level,
747 int optname, char __user *optval,
748 int __user *option);
749#ifdef CONFIG_COMPAT
750 int (*compat_setsockopt)(struct sock *sk,
751 int level,
752 int optname, char __user *optval,
753 unsigned int optlen);
754 int (*compat_getsockopt)(struct sock *sk,
755 int level,
756 int optname, char __user *optval,
757 int __user *option);
758 int (*compat_ioctl)(struct sock *sk,
759 unsigned int cmd, unsigned long arg);
760#endif
761 int (*sendmsg)(struct kiocb *iocb, struct sock *sk,
762 struct msghdr *msg, size_t len);
763 int (*recvmsg)(struct kiocb *iocb, struct sock *sk,
764 struct msghdr *msg,
765 size_t len, int noblock, int flags,
766 int *addr_len);
767 int (*sendpage)(struct sock *sk, struct page *page,
768 int offset, size_t size, int flags);
769 int (*bind)(struct sock *sk,
770 struct sockaddr *uaddr, int addr_len);
771
772 int (*backlog_rcv) (struct sock *sk,
773 struct sk_buff *skb);
774
775 /* Keeping track of sk's, looking them up, and port selection methods. */
776 void (*hash)(struct sock *sk);
777 void (*unhash)(struct sock *sk);
778 void (*rehash)(struct sock *sk);
779 int (*get_port)(struct sock *sk, unsigned short snum);
780 void (*clear_sk)(struct sock *sk, int size);
781
782 /* Keeping track of sockets in use */
783#ifdef CONFIG_PROC_FS
784 unsigned int inuse_idx;
785#endif
786
787 /* Memory pressure */
788 void (*enter_memory_pressure)(struct sock *sk);
789 atomic_long_t *memory_allocated; /* Current allocated memory. */
790 struct percpu_counter *sockets_allocated; /* Current number of sockets. */
791 /*
792 * Pressure flag: try to collapse.
793 * Technical note: it is used by multiple contexts non atomically.
794 * All the __sk_mem_schedule() is of this nature: accounting
795 * is strict, actions are advisory and have some latency.
796 */
797 int *memory_pressure;
798 long *sysctl_mem;
799 int *sysctl_wmem;
800 int *sysctl_rmem;
801 int max_header;
802 bool no_autobind;
803
804 struct kmem_cache *slab;
805 unsigned int obj_size;
806 int slab_flags;
807
808 struct percpu_counter *orphan_count;
809
810 struct request_sock_ops *rsk_prot;
811 struct timewait_sock_ops *twsk_prot;
812
813 union {
814 struct inet_hashinfo *hashinfo;
815 struct udp_table *udp_table;
816 struct raw_hashinfo *raw_hash;
817 } h;
818
819 struct module *owner;
820
821 char name[32];
822
823 struct list_head node;
824#ifdef SOCK_REFCNT_DEBUG
825 atomic_t socks;
826#endif
827};
828
829extern int proto_register(struct proto *prot, int alloc_slab);
830extern void proto_unregister(struct proto *prot);
831
832#ifdef SOCK_REFCNT_DEBUG
833static inline void sk_refcnt_debug_inc(struct sock *sk)
834{
835 atomic_inc(&sk->sk_prot->socks);
836}
837
838static inline void sk_refcnt_debug_dec(struct sock *sk)
839{
840 atomic_dec(&sk->sk_prot->socks);
841 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
842 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
843}
844
845static inline void sk_refcnt_debug_release(const struct sock *sk)
846{
847 if (atomic_read(&sk->sk_refcnt) != 1)
848 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
849 sk->sk_prot->name, sk, atomic_read(&sk->sk_refcnt));
850}
851#else /* SOCK_REFCNT_DEBUG */
852#define sk_refcnt_debug_inc(sk) do { } while (0)
853#define sk_refcnt_debug_dec(sk) do { } while (0)
854#define sk_refcnt_debug_release(sk) do { } while (0)
855#endif /* SOCK_REFCNT_DEBUG */
856
857
858#ifdef CONFIG_PROC_FS
859/* Called with local bh disabled */
860extern void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
861extern int sock_prot_inuse_get(struct net *net, struct proto *proto);
862#else
863static void inline sock_prot_inuse_add(struct net *net, struct proto *prot,
864 int inc)
865{
866}
867#endif
868
869
870/* With per-bucket locks this operation is not-atomic, so that
871 * this version is not worse.
872 */
873static inline void __sk_prot_rehash(struct sock *sk)
874{
875 sk->sk_prot->unhash(sk);
876 sk->sk_prot->hash(sk);
877}
878
879void sk_prot_clear_portaddr_nulls(struct sock *sk, int size);
880
881/* About 10 seconds */
882#define SOCK_DESTROY_TIME (10*HZ)
883
884/* Sockets 0-1023 can't be bound to unless you are superuser */
885#define PROT_SOCK 1024
886
887#define SHUTDOWN_MASK 3
888#define RCV_SHUTDOWN 1
889#define SEND_SHUTDOWN 2
890
891#define SOCK_SNDBUF_LOCK 1
892#define SOCK_RCVBUF_LOCK 2
893#define SOCK_BINDADDR_LOCK 4
894#define SOCK_BINDPORT_LOCK 8
895
896/* sock_iocb: used to kick off async processing of socket ios */
897struct sock_iocb {
898 struct list_head list;
899
900 int flags;
901 int size;
902 struct socket *sock;
903 struct sock *sk;
904 struct scm_cookie *scm;
905 struct msghdr *msg, async_msg;
906 struct kiocb *kiocb;
907};
908
909static inline struct sock_iocb *kiocb_to_siocb(struct kiocb *iocb)
910{
911 return (struct sock_iocb *)iocb->private;
912}
913
914static inline struct kiocb *siocb_to_kiocb(struct sock_iocb *si)
915{
916 return si->kiocb;
917}
918
919struct socket_alloc {
920 struct socket socket;
921 struct inode vfs_inode;
922};
923
924static inline struct socket *SOCKET_I(struct inode *inode)
925{
926 return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
927}
928
929static inline struct inode *SOCK_INODE(struct socket *socket)
930{
931 return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
932}
933
934/*
935 * Functions for memory accounting
936 */
937extern int __sk_mem_schedule(struct sock *sk, int size, int kind);
938extern void __sk_mem_reclaim(struct sock *sk);
939
940#define SK_MEM_QUANTUM ((int)PAGE_SIZE)
941#define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
942#define SK_MEM_SEND 0
943#define SK_MEM_RECV 1
944
945static inline int sk_mem_pages(int amt)
946{
947 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
948}
949
950static inline int sk_has_account(struct sock *sk)
951{
952 /* return true if protocol supports memory accounting */
953 return !!sk->sk_prot->memory_allocated;
954}
955
956static inline int sk_wmem_schedule(struct sock *sk, int size)
957{
958 if (!sk_has_account(sk))
959 return 1;
960 return size <= sk->sk_forward_alloc ||
961 __sk_mem_schedule(sk, size, SK_MEM_SEND);
962}
963
964static inline int sk_rmem_schedule(struct sock *sk, int size)
965{
966 if (!sk_has_account(sk))
967 return 1;
968 return size <= sk->sk_forward_alloc ||
969 __sk_mem_schedule(sk, size, SK_MEM_RECV);
970}
971
972static inline void sk_mem_reclaim(struct sock *sk)
973{
974 if (!sk_has_account(sk))
975 return;
976 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
977 __sk_mem_reclaim(sk);
978}
979
980static inline void sk_mem_reclaim_partial(struct sock *sk)
981{
982 if (!sk_has_account(sk))
983 return;
984 if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
985 __sk_mem_reclaim(sk);
986}
987
988static inline void sk_mem_charge(struct sock *sk, int size)
989{
990 if (!sk_has_account(sk))
991 return;
992 sk->sk_forward_alloc -= size;
993}
994
995static inline void sk_mem_uncharge(struct sock *sk, int size)
996{
997 if (!sk_has_account(sk))
998 return;
999 sk->sk_forward_alloc += size;
1000}
1001
1002static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
1003{
1004 sock_set_flag(sk, SOCK_QUEUE_SHRUNK);
1005 sk->sk_wmem_queued -= skb->truesize;
1006 sk_mem_uncharge(sk, skb->truesize);
1007 __kfree_skb(skb);
1008}
1009
1010/* Used by processes to "lock" a socket state, so that
1011 * interrupts and bottom half handlers won't change it
1012 * from under us. It essentially blocks any incoming
1013 * packets, so that we won't get any new data or any
1014 * packets that change the state of the socket.
1015 *
1016 * While locked, BH processing will add new packets to
1017 * the backlog queue. This queue is processed by the
1018 * owner of the socket lock right before it is released.
1019 *
1020 * Since ~2.3.5 it is also exclusive sleep lock serializing
1021 * accesses from user process context.
1022 */
1023#define sock_owned_by_user(sk) ((sk)->sk_lock.owned)
1024
1025/*
1026 * Macro so as to not evaluate some arguments when
1027 * lockdep is not enabled.
1028 *
1029 * Mark both the sk_lock and the sk_lock.slock as a
1030 * per-address-family lock class.
1031 */
1032#define sock_lock_init_class_and_name(sk, sname, skey, name, key) \
1033do { \
1034 sk->sk_lock.owned = 0; \
1035 init_waitqueue_head(&sk->sk_lock.wq); \
1036 spin_lock_init(&(sk)->sk_lock.slock); \
1037 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \
1038 sizeof((sk)->sk_lock)); \
1039 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \
1040 (skey), (sname)); \
1041 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \
1042} while (0)
1043
1044extern void lock_sock_nested(struct sock *sk, int subclass);
1045
1046static inline void lock_sock(struct sock *sk)
1047{
1048 lock_sock_nested(sk, 0);
1049}
1050
1051extern void release_sock(struct sock *sk);
1052
1053/* BH context may only use the following locking interface. */
1054#define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock))
1055#define bh_lock_sock_nested(__sk) \
1056 spin_lock_nested(&((__sk)->sk_lock.slock), \
1057 SINGLE_DEPTH_NESTING)
1058#define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock))
1059
1060extern bool lock_sock_fast(struct sock *sk);
1061/**
1062 * unlock_sock_fast - complement of lock_sock_fast
1063 * @sk: socket
1064 * @slow: slow mode
1065 *
1066 * fast unlock socket for user context.
1067 * If slow mode is on, we call regular release_sock()
1068 */
1069static inline void unlock_sock_fast(struct sock *sk, bool slow)
1070{
1071 if (slow)
1072 release_sock(sk);
1073 else
1074 spin_unlock_bh(&sk->sk_lock.slock);
1075}
1076
1077
1078extern struct sock *sk_alloc(struct net *net, int family,
1079 gfp_t priority,
1080 struct proto *prot);
1081extern void sk_free(struct sock *sk);
1082extern void sk_release_kernel(struct sock *sk);
1083extern struct sock *sk_clone(const struct sock *sk,
1084 const gfp_t priority);
1085
1086extern struct sk_buff *sock_wmalloc(struct sock *sk,
1087 unsigned long size, int force,
1088 gfp_t priority);
1089extern struct sk_buff *sock_rmalloc(struct sock *sk,
1090 unsigned long size, int force,
1091 gfp_t priority);
1092extern void sock_wfree(struct sk_buff *skb);
1093extern void sock_rfree(struct sk_buff *skb);
1094
1095extern int sock_setsockopt(struct socket *sock, int level,
1096 int op, char __user *optval,
1097 unsigned int optlen);
1098
1099extern int sock_getsockopt(struct socket *sock, int level,
1100 int op, char __user *optval,
1101 int __user *optlen);
1102extern struct sk_buff *sock_alloc_send_skb(struct sock *sk,
1103 unsigned long size,
1104 int noblock,
1105 int *errcode);
1106extern struct sk_buff *sock_alloc_send_pskb(struct sock *sk,
1107 unsigned long header_len,
1108 unsigned long data_len,
1109 int noblock,
1110 int *errcode);
1111extern void *sock_kmalloc(struct sock *sk, int size,
1112 gfp_t priority);
1113extern void sock_kfree_s(struct sock *sk, void *mem, int size);
1114extern void sk_send_sigurg(struct sock *sk);
1115
1116#ifdef CONFIG_CGROUPS
1117extern void sock_update_classid(struct sock *sk);
1118#else
1119static inline void sock_update_classid(struct sock *sk)
1120{
1121}
1122#endif
1123
1124/*
1125 * Functions to fill in entries in struct proto_ops when a protocol
1126 * does not implement a particular function.
1127 */
1128extern int sock_no_bind(struct socket *,
1129 struct sockaddr *, int);
1130extern int sock_no_connect(struct socket *,
1131 struct sockaddr *, int, int);
1132extern int sock_no_socketpair(struct socket *,
1133 struct socket *);
1134extern int sock_no_accept(struct socket *,
1135 struct socket *, int);
1136extern int sock_no_getname(struct socket *,
1137 struct sockaddr *, int *, int);
1138extern unsigned int sock_no_poll(struct file *, struct socket *,
1139 struct poll_table_struct *);
1140extern int sock_no_ioctl(struct socket *, unsigned int,
1141 unsigned long);
1142extern int sock_no_listen(struct socket *, int);
1143extern int sock_no_shutdown(struct socket *, int);
1144extern int sock_no_getsockopt(struct socket *, int , int,
1145 char __user *, int __user *);
1146extern int sock_no_setsockopt(struct socket *, int, int,
1147 char __user *, unsigned int);
1148extern int sock_no_sendmsg(struct kiocb *, struct socket *,
1149 struct msghdr *, size_t);
1150extern int sock_no_recvmsg(struct kiocb *, struct socket *,
1151 struct msghdr *, size_t, int);
1152extern int sock_no_mmap(struct file *file,
1153 struct socket *sock,
1154 struct vm_area_struct *vma);
1155extern ssize_t sock_no_sendpage(struct socket *sock,
1156 struct page *page,
1157 int offset, size_t size,
1158 int flags);
1159
1160/*
1161 * Functions to fill in entries in struct proto_ops when a protocol
1162 * uses the inet style.
1163 */
1164extern int sock_common_getsockopt(struct socket *sock, int level, int optname,
1165 char __user *optval, int __user *optlen);
1166extern int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
1167 struct msghdr *msg, size_t size, int flags);
1168extern int sock_common_setsockopt(struct socket *sock, int level, int optname,
1169 char __user *optval, unsigned int optlen);
1170extern int compat_sock_common_getsockopt(struct socket *sock, int level,
1171 int optname, char __user *optval, int __user *optlen);
1172extern int compat_sock_common_setsockopt(struct socket *sock, int level,
1173 int optname, char __user *optval, unsigned int optlen);
1174
1175extern void sk_common_release(struct sock *sk);
1176
1177/*
1178 * Default socket callbacks and setup code
1179 */
1180
1181/* Initialise core socket variables */
1182extern void sock_init_data(struct socket *sock, struct sock *sk);
1183
1184extern void sk_filter_release_rcu(struct rcu_head *rcu);
1185
1186/**
1187 * sk_filter_release - release a socket filter
1188 * @fp: filter to remove
1189 *
1190 * Remove a filter from a socket and release its resources.
1191 */
1192
1193static inline void sk_filter_release(struct sk_filter *fp)
1194{
1195 if (atomic_dec_and_test(&fp->refcnt))
1196 call_rcu(&fp->rcu, sk_filter_release_rcu);
1197}
1198
1199static inline void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp)
1200{
1201 unsigned int size = sk_filter_len(fp);
1202
1203 atomic_sub(size, &sk->sk_omem_alloc);
1204 sk_filter_release(fp);
1205}
1206
1207static inline void sk_filter_charge(struct sock *sk, struct sk_filter *fp)
1208{
1209 atomic_inc(&fp->refcnt);
1210 atomic_add(sk_filter_len(fp), &sk->sk_omem_alloc);
1211}
1212
1213/*
1214 * Socket reference counting postulates.
1215 *
1216 * * Each user of socket SHOULD hold a reference count.
1217 * * Each access point to socket (an hash table bucket, reference from a list,
1218 * running timer, skb in flight MUST hold a reference count.
1219 * * When reference count hits 0, it means it will never increase back.
1220 * * When reference count hits 0, it means that no references from
1221 * outside exist to this socket and current process on current CPU
1222 * is last user and may/should destroy this socket.
1223 * * sk_free is called from any context: process, BH, IRQ. When
1224 * it is called, socket has no references from outside -> sk_free
1225 * may release descendant resources allocated by the socket, but
1226 * to the time when it is called, socket is NOT referenced by any
1227 * hash tables, lists etc.
1228 * * Packets, delivered from outside (from network or from another process)
1229 * and enqueued on receive/error queues SHOULD NOT grab reference count,
1230 * when they sit in queue. Otherwise, packets will leak to hole, when
1231 * socket is looked up by one cpu and unhasing is made by another CPU.
1232 * It is true for udp/raw, netlink (leak to receive and error queues), tcp
1233 * (leak to backlog). Packet socket does all the processing inside
1234 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1235 * use separate SMP lock, so that they are prone too.
1236 */
1237
1238/* Ungrab socket and destroy it, if it was the last reference. */
1239static inline void sock_put(struct sock *sk)
1240{
1241 if (atomic_dec_and_test(&sk->sk_refcnt))
1242 sk_free(sk);
1243}
1244
1245extern int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1246 const int nested);
1247
1248static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1249{
1250 sk->sk_tx_queue_mapping = tx_queue;
1251}
1252
1253static inline void sk_tx_queue_clear(struct sock *sk)
1254{
1255 sk->sk_tx_queue_mapping = -1;
1256}
1257
1258static inline int sk_tx_queue_get(const struct sock *sk)
1259{
1260 return sk ? sk->sk_tx_queue_mapping : -1;
1261}
1262
1263static inline void sk_set_socket(struct sock *sk, struct socket *sock)
1264{
1265 sk_tx_queue_clear(sk);
1266 sk->sk_socket = sock;
1267}
1268
1269static inline wait_queue_head_t *sk_sleep(struct sock *sk)
1270{
1271 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
1272 return &rcu_dereference_raw(sk->sk_wq)->wait;
1273}
1274/* Detach socket from process context.
1275 * Announce socket dead, detach it from wait queue and inode.
1276 * Note that parent inode held reference count on this struct sock,
1277 * we do not release it in this function, because protocol
1278 * probably wants some additional cleanups or even continuing
1279 * to work with this socket (TCP).
1280 */
1281static inline void sock_orphan(struct sock *sk)
1282{
1283 write_lock_bh(&sk->sk_callback_lock);
1284 sock_set_flag(sk, SOCK_DEAD);
1285 sk_set_socket(sk, NULL);
1286 sk->sk_wq = NULL;
1287 write_unlock_bh(&sk->sk_callback_lock);
1288}
1289
1290static inline void sock_graft(struct sock *sk, struct socket *parent)
1291{
1292 write_lock_bh(&sk->sk_callback_lock);
1293 sk->sk_wq = parent->wq;
1294 parent->sk = sk;
1295 sk_set_socket(sk, parent);
1296 security_sock_graft(sk, parent);
1297 write_unlock_bh(&sk->sk_callback_lock);
1298}
1299
1300extern int sock_i_uid(struct sock *sk);
1301extern unsigned long sock_i_ino(struct sock *sk);
1302
1303static inline struct dst_entry *
1304__sk_dst_get(struct sock *sk)
1305{
1306 return rcu_dereference_check(sk->sk_dst_cache, sock_owned_by_user(sk) ||
1307 lockdep_is_held(&sk->sk_lock.slock));
1308}
1309
1310static inline struct dst_entry *
1311sk_dst_get(struct sock *sk)
1312{
1313 struct dst_entry *dst;
1314
1315 rcu_read_lock();
1316 dst = rcu_dereference(sk->sk_dst_cache);
1317 if (dst)
1318 dst_hold(dst);
1319 rcu_read_unlock();
1320 return dst;
1321}
1322
1323extern void sk_reset_txq(struct sock *sk);
1324
1325static inline void dst_negative_advice(struct sock *sk)
1326{
1327 struct dst_entry *ndst, *dst = __sk_dst_get(sk);
1328
1329 if (dst && dst->ops->negative_advice) {
1330 ndst = dst->ops->negative_advice(dst);
1331
1332 if (ndst != dst) {
1333 rcu_assign_pointer(sk->sk_dst_cache, ndst);
1334 sk_reset_txq(sk);
1335 }
1336 }
1337}
1338
1339static inline void
1340__sk_dst_set(struct sock *sk, struct dst_entry *dst)
1341{
1342 struct dst_entry *old_dst;
1343
1344 sk_tx_queue_clear(sk);
1345 /*
1346 * This can be called while sk is owned by the caller only,
1347 * with no state that can be checked in a rcu_dereference_check() cond
1348 */
1349 old_dst = rcu_dereference_raw(sk->sk_dst_cache);
1350 rcu_assign_pointer(sk->sk_dst_cache, dst);
1351 dst_release(old_dst);
1352}
1353
1354static inline void
1355sk_dst_set(struct sock *sk, struct dst_entry *dst)
1356{
1357 spin_lock(&sk->sk_dst_lock);
1358 __sk_dst_set(sk, dst);
1359 spin_unlock(&sk->sk_dst_lock);
1360}
1361
1362static inline void
1363__sk_dst_reset(struct sock *sk)
1364{
1365 __sk_dst_set(sk, NULL);
1366}
1367
1368static inline void
1369sk_dst_reset(struct sock *sk)
1370{
1371 spin_lock(&sk->sk_dst_lock);
1372 __sk_dst_reset(sk);
1373 spin_unlock(&sk->sk_dst_lock);
1374}
1375
1376extern struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
1377
1378extern struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
1379
1380static inline int sk_can_gso(const struct sock *sk)
1381{
1382 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
1383}
1384
1385extern void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
1386
1387static inline void sk_nocaps_add(struct sock *sk, int flags)
1388{
1389 sk->sk_route_nocaps |= flags;
1390 sk->sk_route_caps &= ~flags;
1391}
1392
1393static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
1394 char __user *from, char *to,
1395 int copy, int offset)
1396{
1397 if (skb->ip_summed == CHECKSUM_NONE) {
1398 int err = 0;
1399 __wsum csum = csum_and_copy_from_user(from, to, copy, 0, &err);
1400 if (err)
1401 return err;
1402 skb->csum = csum_block_add(skb->csum, csum, offset);
1403 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
1404 if (!access_ok(VERIFY_READ, from, copy) ||
1405 __copy_from_user_nocache(to, from, copy))
1406 return -EFAULT;
1407 } else if (copy_from_user(to, from, copy))
1408 return -EFAULT;
1409
1410 return 0;
1411}
1412
1413static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
1414 char __user *from, int copy)
1415{
1416 int err, offset = skb->len;
1417
1418 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
1419 copy, offset);
1420 if (err)
1421 __skb_trim(skb, offset);
1422
1423 return err;
1424}
1425
1426static inline int skb_copy_to_page_nocache(struct sock *sk, char __user *from,
1427 struct sk_buff *skb,
1428 struct page *page,
1429 int off, int copy)
1430{
1431 int err;
1432
1433 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
1434 copy, skb->len);
1435 if (err)
1436 return err;
1437
1438 skb->len += copy;
1439 skb->data_len += copy;
1440 skb->truesize += copy;
1441 sk->sk_wmem_queued += copy;
1442 sk_mem_charge(sk, copy);
1443 return 0;
1444}
1445
1446static inline int skb_copy_to_page(struct sock *sk, char __user *from,
1447 struct sk_buff *skb, struct page *page,
1448 int off, int copy)
1449{
1450 if (skb->ip_summed == CHECKSUM_NONE) {
1451 int err = 0;
1452 __wsum csum = csum_and_copy_from_user(from,
1453 page_address(page) + off,
1454 copy, 0, &err);
1455 if (err)
1456 return err;
1457 skb->csum = csum_block_add(skb->csum, csum, skb->len);
1458 } else if (copy_from_user(page_address(page) + off, from, copy))
1459 return -EFAULT;
1460
1461 skb->len += copy;
1462 skb->data_len += copy;
1463 skb->truesize += copy;
1464 sk->sk_wmem_queued += copy;
1465 sk_mem_charge(sk, copy);
1466 return 0;
1467}
1468
1469/**
1470 * sk_wmem_alloc_get - returns write allocations
1471 * @sk: socket
1472 *
1473 * Returns sk_wmem_alloc minus initial offset of one
1474 */
1475static inline int sk_wmem_alloc_get(const struct sock *sk)
1476{
1477 return atomic_read(&sk->sk_wmem_alloc) - 1;
1478}
1479
1480/**
1481 * sk_rmem_alloc_get - returns read allocations
1482 * @sk: socket
1483 *
1484 * Returns sk_rmem_alloc
1485 */
1486static inline int sk_rmem_alloc_get(const struct sock *sk)
1487{
1488 return atomic_read(&sk->sk_rmem_alloc);
1489}
1490
1491/**
1492 * sk_has_allocations - check if allocations are outstanding
1493 * @sk: socket
1494 *
1495 * Returns true if socket has write or read allocations
1496 */
1497static inline int sk_has_allocations(const struct sock *sk)
1498{
1499 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
1500}
1501
1502/**
1503 * wq_has_sleeper - check if there are any waiting processes
1504 * @wq: struct socket_wq
1505 *
1506 * Returns true if socket_wq has waiting processes
1507 *
1508 * The purpose of the wq_has_sleeper and sock_poll_wait is to wrap the memory
1509 * barrier call. They were added due to the race found within the tcp code.
1510 *
1511 * Consider following tcp code paths:
1512 *
1513 * CPU1 CPU2
1514 *
1515 * sys_select receive packet
1516 * ... ...
1517 * __add_wait_queue update tp->rcv_nxt
1518 * ... ...
1519 * tp->rcv_nxt check sock_def_readable
1520 * ... {
1521 * schedule rcu_read_lock();
1522 * wq = rcu_dereference(sk->sk_wq);
1523 * if (wq && waitqueue_active(&wq->wait))
1524 * wake_up_interruptible(&wq->wait)
1525 * ...
1526 * }
1527 *
1528 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
1529 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1
1530 * could then endup calling schedule and sleep forever if there are no more
1531 * data on the socket.
1532 *
1533 */
1534static inline bool wq_has_sleeper(struct socket_wq *wq)
1535{
1536
1537 /*
1538 * We need to be sure we are in sync with the
1539 * add_wait_queue modifications to the wait queue.
1540 *
1541 * This memory barrier is paired in the sock_poll_wait.
1542 */
1543 smp_mb();
1544 return wq && waitqueue_active(&wq->wait);
1545}
1546
1547/**
1548 * sock_poll_wait - place memory barrier behind the poll_wait call.
1549 * @filp: file
1550 * @wait_address: socket wait queue
1551 * @p: poll_table
1552 *
1553 * See the comments in the wq_has_sleeper function.
1554 */
1555static inline void sock_poll_wait(struct file *filp,
1556 wait_queue_head_t *wait_address, poll_table *p)
1557{
1558 if (p && wait_address) {
1559 poll_wait(filp, wait_address, p);
1560 /*
1561 * We need to be sure we are in sync with the
1562 * socket flags modification.
1563 *
1564 * This memory barrier is paired in the wq_has_sleeper.
1565 */
1566 smp_mb();
1567 }
1568}
1569
1570/*
1571 * Queue a received datagram if it will fit. Stream and sequenced
1572 * protocols can't normally use this as they need to fit buffers in
1573 * and play with them.
1574 *
1575 * Inlined as it's very short and called for pretty much every
1576 * packet ever received.
1577 */
1578
1579static inline void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1580{
1581 skb_orphan(skb);
1582 skb->sk = sk;
1583 skb->destructor = sock_wfree;
1584 /*
1585 * We used to take a refcount on sk, but following operation
1586 * is enough to guarantee sk_free() wont free this sock until
1587 * all in-flight packets are completed
1588 */
1589 atomic_add(skb->truesize, &sk->sk_wmem_alloc);
1590}
1591
1592static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
1593{
1594 skb_orphan(skb);
1595 skb->sk = sk;
1596 skb->destructor = sock_rfree;
1597 atomic_add(skb->truesize, &sk->sk_rmem_alloc);
1598 sk_mem_charge(sk, skb->truesize);
1599}
1600
1601extern void sk_reset_timer(struct sock *sk, struct timer_list* timer,
1602 unsigned long expires);
1603
1604extern void sk_stop_timer(struct sock *sk, struct timer_list* timer);
1605
1606extern int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
1607
1608extern int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
1609
1610/*
1611 * Recover an error report and clear atomically
1612 */
1613
1614static inline int sock_error(struct sock *sk)
1615{
1616 int err;
1617 if (likely(!sk->sk_err))
1618 return 0;
1619 err = xchg(&sk->sk_err, 0);
1620 return -err;
1621}
1622
1623static inline unsigned long sock_wspace(struct sock *sk)
1624{
1625 int amt = 0;
1626
1627 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
1628 amt = sk->sk_sndbuf - atomic_read(&sk->sk_wmem_alloc);
1629 if (amt < 0)
1630 amt = 0;
1631 }
1632 return amt;
1633}
1634
1635static inline void sk_wake_async(struct sock *sk, int how, int band)
1636{
1637 if (sock_flag(sk, SOCK_FASYNC))
1638 sock_wake_async(sk->sk_socket, how, band);
1639}
1640
1641#define SOCK_MIN_SNDBUF 2048
1642/*
1643 * Since sk_rmem_alloc sums skb->truesize, even a small frame might need
1644 * sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak
1645 */
1646#define SOCK_MIN_RCVBUF (2048 + sizeof(struct sk_buff))
1647
1648static inline void sk_stream_moderate_sndbuf(struct sock *sk)
1649{
1650 if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) {
1651 sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
1652 sk->sk_sndbuf = max(sk->sk_sndbuf, SOCK_MIN_SNDBUF);
1653 }
1654}
1655
1656struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp);
1657
1658static inline struct page *sk_stream_alloc_page(struct sock *sk)
1659{
1660 struct page *page = NULL;
1661
1662 page = alloc_pages(sk->sk_allocation, 0);
1663 if (!page) {
1664 sk->sk_prot->enter_memory_pressure(sk);
1665 sk_stream_moderate_sndbuf(sk);
1666 }
1667 return page;
1668}
1669
1670/*
1671 * Default write policy as shown to user space via poll/select/SIGIO
1672 */
1673static inline int sock_writeable(const struct sock *sk)
1674{
1675 return atomic_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf >> 1);
1676}
1677
1678static inline gfp_t gfp_any(void)
1679{
1680 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
1681}
1682
1683static inline long sock_rcvtimeo(const struct sock *sk, int noblock)
1684{
1685 return noblock ? 0 : sk->sk_rcvtimeo;
1686}
1687
1688static inline long sock_sndtimeo(const struct sock *sk, int noblock)
1689{
1690 return noblock ? 0 : sk->sk_sndtimeo;
1691}
1692
1693static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
1694{
1695 return (waitall ? len : min_t(int, sk->sk_rcvlowat, len)) ? : 1;
1696}
1697
1698/* Alas, with timeout socket operations are not restartable.
1699 * Compare this to poll().
1700 */
1701static inline int sock_intr_errno(long timeo)
1702{
1703 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
1704}
1705
1706extern void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
1707 struct sk_buff *skb);
1708
1709static __inline__ void
1710sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
1711{
1712 ktime_t kt = skb->tstamp;
1713 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
1714
1715 /*
1716 * generate control messages if
1717 * - receive time stamping in software requested (SOCK_RCVTSTAMP
1718 * or SOCK_TIMESTAMPING_RX_SOFTWARE)
1719 * - software time stamp available and wanted
1720 * (SOCK_TIMESTAMPING_SOFTWARE)
1721 * - hardware time stamps available and wanted
1722 * (SOCK_TIMESTAMPING_SYS_HARDWARE or
1723 * SOCK_TIMESTAMPING_RAW_HARDWARE)
1724 */
1725 if (sock_flag(sk, SOCK_RCVTSTAMP) ||
1726 sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE) ||
1727 (kt.tv64 && sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE)) ||
1728 (hwtstamps->hwtstamp.tv64 &&
1729 sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE)) ||
1730 (hwtstamps->syststamp.tv64 &&
1731 sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE)))
1732 __sock_recv_timestamp(msg, sk, skb);
1733 else
1734 sk->sk_stamp = kt;
1735}
1736
1737extern void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
1738 struct sk_buff *skb);
1739
1740static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
1741 struct sk_buff *skb)
1742{
1743#define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \
1744 (1UL << SOCK_RCVTSTAMP) | \
1745 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
1746 (1UL << SOCK_TIMESTAMPING_SOFTWARE) | \
1747 (1UL << SOCK_TIMESTAMPING_RAW_HARDWARE) | \
1748 (1UL << SOCK_TIMESTAMPING_SYS_HARDWARE))
1749
1750 if (sk->sk_flags & FLAGS_TS_OR_DROPS)
1751 __sock_recv_ts_and_drops(msg, sk, skb);
1752 else
1753 sk->sk_stamp = skb->tstamp;
1754}
1755
1756/**
1757 * sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
1758 * @sk: socket sending this packet
1759 * @tx_flags: filled with instructions for time stamping
1760 *
1761 * Currently only depends on SOCK_TIMESTAMPING* flags. Returns error code if
1762 * parameters are invalid.
1763 */
1764extern int sock_tx_timestamp(struct sock *sk, __u8 *tx_flags);
1765
1766/**
1767 * sk_eat_skb - Release a skb if it is no longer needed
1768 * @sk: socket to eat this skb from
1769 * @skb: socket buffer to eat
1770 * @copied_early: flag indicating whether DMA operations copied this data early
1771 *
1772 * This routine must be called with interrupts disabled or with the socket
1773 * locked so that the sk_buff queue operation is ok.
1774*/
1775#ifdef CONFIG_NET_DMA
1776static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, int copied_early)
1777{
1778 __skb_unlink(skb, &sk->sk_receive_queue);
1779 if (!copied_early)
1780 __kfree_skb(skb);
1781 else
1782 __skb_queue_tail(&sk->sk_async_wait_queue, skb);
1783}
1784#else
1785static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb, int copied_early)
1786{
1787 __skb_unlink(skb, &sk->sk_receive_queue);
1788 __kfree_skb(skb);
1789}
1790#endif
1791
1792static inline
1793struct net *sock_net(const struct sock *sk)
1794{
1795 return read_pnet(&sk->sk_net);
1796}
1797
1798static inline
1799void sock_net_set(struct sock *sk, struct net *net)
1800{
1801 write_pnet(&sk->sk_net, net);
1802}
1803
1804/*
1805 * Kernel sockets, f.e. rtnl or icmp_socket, are a part of a namespace.
1806 * They should not hold a reference to a namespace in order to allow
1807 * to stop it.
1808 * Sockets after sk_change_net should be released using sk_release_kernel
1809 */
1810static inline void sk_change_net(struct sock *sk, struct net *net)
1811{
1812 put_net(sock_net(sk));
1813 sock_net_set(sk, hold_net(net));
1814}
1815
1816static inline struct sock *skb_steal_sock(struct sk_buff *skb)
1817{
1818 if (unlikely(skb->sk)) {
1819 struct sock *sk = skb->sk;
1820
1821 skb->destructor = NULL;
1822 skb->sk = NULL;
1823 return sk;
1824 }
1825 return NULL;
1826}
1827
1828extern void sock_enable_timestamp(struct sock *sk, int flag);
1829extern int sock_get_timestamp(struct sock *, struct timeval __user *);
1830extern int sock_get_timestampns(struct sock *, struct timespec __user *);
1831
1832/*
1833 * Enable debug/info messages
1834 */
1835extern int net_msg_warn;
1836#define NETDEBUG(fmt, args...) \
1837 do { if (net_msg_warn) printk(fmt,##args); } while (0)
1838
1839#define LIMIT_NETDEBUG(fmt, args...) \
1840 do { if (net_msg_warn && net_ratelimit()) printk(fmt,##args); } while(0)
1841
1842extern __u32 sysctl_wmem_max;
1843extern __u32 sysctl_rmem_max;
1844
1845extern void sk_init(void);
1846
1847extern int sysctl_optmem_max;
1848
1849extern __u32 sysctl_wmem_default;
1850extern __u32 sysctl_rmem_default;
1851
1852#endif /* _SOCK_H */
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(&sk->sk_net);
649}
650
651static inline
652void sock_net_set(struct sock *sk, struct net *net)
653{
654 write_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);
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(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(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(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(&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(&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(&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(&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(&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(&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(&sk->sk_node, 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(&sk->sk_node, list);
836 else
837 hlist_add_head_rcu(&sk->sk_node, 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(&sk->sk_node, 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(&sk->sk_nulls_node, 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(&sk->sk_nulls_node, 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(&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(&sk->sk_bind_node, 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, bit);
971 else
972 sock_reset_flag(sk, 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(&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, 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, 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, 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(sock_cgroup_ptr(&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(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(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 proto_memory_pcpu_drain(struct proto *proto)
1414{
1415 int val = this_cpu_xchg(*proto->per_cpu_fw_alloc, 0);
1416
1417 if (val)
1418 atomic_long_add(val, proto->memory_allocated);
1419}
1420
1421static inline void
1422sk_memory_allocated_add(const struct sock *sk, int val)
1423{
1424 struct proto *proto = sk->sk_prot;
1425
1426 val = this_cpu_add_return(*proto->per_cpu_fw_alloc, val);
1427
1428 if (unlikely(val >= READ_ONCE(sysctl_mem_pcpu_rsv)))
1429 proto_memory_pcpu_drain(proto);
1430}
1431
1432static inline void
1433sk_memory_allocated_sub(const struct sock *sk, int val)
1434{
1435 struct proto *proto = sk->sk_prot;
1436
1437 val = this_cpu_sub_return(*proto->per_cpu_fw_alloc, val);
1438
1439 if (unlikely(val <= -READ_ONCE(sysctl_mem_pcpu_rsv)))
1440 proto_memory_pcpu_drain(proto);
1441}
1442
1443#define SK_ALLOC_PERCPU_COUNTER_BATCH 16
1444
1445static inline void sk_sockets_allocated_dec(struct sock *sk)
1446{
1447 percpu_counter_add_batch(sk->sk_prot->sockets_allocated, -1,
1448 SK_ALLOC_PERCPU_COUNTER_BATCH);
1449}
1450
1451static inline void sk_sockets_allocated_inc(struct sock *sk)
1452{
1453 percpu_counter_add_batch(sk->sk_prot->sockets_allocated, 1,
1454 SK_ALLOC_PERCPU_COUNTER_BATCH);
1455}
1456
1457static inline u64
1458sk_sockets_allocated_read_positive(struct sock *sk)
1459{
1460 return percpu_counter_read_positive(sk->sk_prot->sockets_allocated);
1461}
1462
1463static inline int
1464proto_sockets_allocated_sum_positive(struct proto *prot)
1465{
1466 return percpu_counter_sum_positive(prot->sockets_allocated);
1467}
1468
1469static inline bool
1470proto_memory_pressure(struct proto *prot)
1471{
1472 if (!prot->memory_pressure)
1473 return false;
1474 return !!READ_ONCE(*prot->memory_pressure);
1475}
1476
1477
1478#ifdef CONFIG_PROC_FS
1479#define PROTO_INUSE_NR 64 /* should be enough for the first time */
1480struct prot_inuse {
1481 int all;
1482 int val[PROTO_INUSE_NR];
1483};
1484
1485static inline void sock_prot_inuse_add(const struct net *net,
1486 const struct proto *prot, int val)
1487{
1488 this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val);
1489}
1490
1491static inline void sock_inuse_add(const struct net *net, int val)
1492{
1493 this_cpu_add(net->core.prot_inuse->all, val);
1494}
1495
1496int sock_prot_inuse_get(struct net *net, struct proto *proto);
1497int sock_inuse_get(struct net *net);
1498#else
1499static inline void sock_prot_inuse_add(const struct net *net,
1500 const struct proto *prot, int val)
1501{
1502}
1503
1504static inline void sock_inuse_add(const struct net *net, int val)
1505{
1506}
1507#endif
1508
1509
1510/* With per-bucket locks this operation is not-atomic, so that
1511 * this version is not worse.
1512 */
1513static inline int __sk_prot_rehash(struct sock *sk)
1514{
1515 sk->sk_prot->unhash(sk);
1516 return sk->sk_prot->hash(sk);
1517}
1518
1519/* About 10 seconds */
1520#define SOCK_DESTROY_TIME (10*HZ)
1521
1522/* Sockets 0-1023 can't be bound to unless you are superuser */
1523#define PROT_SOCK 1024
1524
1525#define SHUTDOWN_MASK 3
1526#define RCV_SHUTDOWN 1
1527#define SEND_SHUTDOWN 2
1528
1529#define SOCK_BINDADDR_LOCK 4
1530#define SOCK_BINDPORT_LOCK 8
1531
1532struct socket_alloc {
1533 struct socket socket;
1534 struct inode vfs_inode;
1535};
1536
1537static inline struct socket *SOCKET_I(struct inode *inode)
1538{
1539 return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1540}
1541
1542static inline struct inode *SOCK_INODE(struct socket *socket)
1543{
1544 return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1545}
1546
1547/*
1548 * Functions for memory accounting
1549 */
1550int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind);
1551int __sk_mem_schedule(struct sock *sk, int size, int kind);
1552void __sk_mem_reduce_allocated(struct sock *sk, int amount);
1553void __sk_mem_reclaim(struct sock *sk, int amount);
1554
1555#define SK_MEM_SEND 0
1556#define SK_MEM_RECV 1
1557
1558/* sysctl_mem values are in pages */
1559static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1560{
1561 return READ_ONCE(sk->sk_prot->sysctl_mem[index]);
1562}
1563
1564static inline int sk_mem_pages(int amt)
1565{
1566 return (amt + PAGE_SIZE - 1) >> PAGE_SHIFT;
1567}
1568
1569static inline bool sk_has_account(struct sock *sk)
1570{
1571 /* return true if protocol supports memory accounting */
1572 return !!sk->sk_prot->memory_allocated;
1573}
1574
1575static inline bool sk_wmem_schedule(struct sock *sk, int size)
1576{
1577 int delta;
1578
1579 if (!sk_has_account(sk))
1580 return true;
1581 delta = size - sk->sk_forward_alloc;
1582 return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_SEND);
1583}
1584
1585static inline bool
1586sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
1587{
1588 int delta;
1589
1590 if (!sk_has_account(sk))
1591 return true;
1592 delta = size - sk->sk_forward_alloc;
1593 return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_RECV) ||
1594 skb_pfmemalloc(skb);
1595}
1596
1597static inline int sk_unused_reserved_mem(const struct sock *sk)
1598{
1599 int unused_mem;
1600
1601 if (likely(!sk->sk_reserved_mem))
1602 return 0;
1603
1604 unused_mem = sk->sk_reserved_mem - sk->sk_wmem_queued -
1605 atomic_read(&sk->sk_rmem_alloc);
1606
1607 return unused_mem > 0 ? unused_mem : 0;
1608}
1609
1610static inline void sk_mem_reclaim(struct sock *sk)
1611{
1612 int reclaimable;
1613
1614 if (!sk_has_account(sk))
1615 return;
1616
1617 reclaimable = sk->sk_forward_alloc - sk_unused_reserved_mem(sk);
1618
1619 if (reclaimable >= (int)PAGE_SIZE)
1620 __sk_mem_reclaim(sk, reclaimable);
1621}
1622
1623static inline void sk_mem_reclaim_final(struct sock *sk)
1624{
1625 sk->sk_reserved_mem = 0;
1626 sk_mem_reclaim(sk);
1627}
1628
1629static inline void sk_mem_charge(struct sock *sk, int size)
1630{
1631 if (!sk_has_account(sk))
1632 return;
1633 sk_forward_alloc_add(sk, -size);
1634}
1635
1636static inline void sk_mem_uncharge(struct sock *sk, int size)
1637{
1638 if (!sk_has_account(sk))
1639 return;
1640 sk_forward_alloc_add(sk, size);
1641 sk_mem_reclaim(sk);
1642}
1643
1644/*
1645 * Macro so as to not evaluate some arguments when
1646 * lockdep is not enabled.
1647 *
1648 * Mark both the sk_lock and the sk_lock.slock as a
1649 * per-address-family lock class.
1650 */
1651#define sock_lock_init_class_and_name(sk, sname, skey, name, key) \
1652do { \
1653 sk->sk_lock.owned = 0; \
1654 init_waitqueue_head(&sk->sk_lock.wq); \
1655 spin_lock_init(&(sk)->sk_lock.slock); \
1656 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \
1657 sizeof((sk)->sk_lock)); \
1658 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \
1659 (skey), (sname)); \
1660 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \
1661} while (0)
1662
1663static inline bool lockdep_sock_is_held(const struct sock *sk)
1664{
1665 return lockdep_is_held(&sk->sk_lock) ||
1666 lockdep_is_held(&sk->sk_lock.slock);
1667}
1668
1669void lock_sock_nested(struct sock *sk, int subclass);
1670
1671static inline void lock_sock(struct sock *sk)
1672{
1673 lock_sock_nested(sk, 0);
1674}
1675
1676void __lock_sock(struct sock *sk);
1677void __release_sock(struct sock *sk);
1678void release_sock(struct sock *sk);
1679
1680/* BH context may only use the following locking interface. */
1681#define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock))
1682#define bh_lock_sock_nested(__sk) \
1683 spin_lock_nested(&((__sk)->sk_lock.slock), \
1684 SINGLE_DEPTH_NESTING)
1685#define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock))
1686
1687bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock);
1688
1689/**
1690 * lock_sock_fast - fast version of lock_sock
1691 * @sk: socket
1692 *
1693 * This version should be used for very small section, where process wont block
1694 * return false if fast path is taken:
1695 *
1696 * sk_lock.slock locked, owned = 0, BH disabled
1697 *
1698 * return true if slow path is taken:
1699 *
1700 * sk_lock.slock unlocked, owned = 1, BH enabled
1701 */
1702static inline bool lock_sock_fast(struct sock *sk)
1703{
1704 /* The sk_lock has mutex_lock() semantics here. */
1705 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
1706
1707 return __lock_sock_fast(sk);
1708}
1709
1710/* fast socket lock variant for caller already holding a [different] socket lock */
1711static inline bool lock_sock_fast_nested(struct sock *sk)
1712{
1713 mutex_acquire(&sk->sk_lock.dep_map, SINGLE_DEPTH_NESTING, 0, _RET_IP_);
1714
1715 return __lock_sock_fast(sk);
1716}
1717
1718/**
1719 * unlock_sock_fast - complement of lock_sock_fast
1720 * @sk: socket
1721 * @slow: slow mode
1722 *
1723 * fast unlock socket for user context.
1724 * If slow mode is on, we call regular release_sock()
1725 */
1726static inline void unlock_sock_fast(struct sock *sk, bool slow)
1727 __releases(&sk->sk_lock.slock)
1728{
1729 if (slow) {
1730 release_sock(sk);
1731 __release(&sk->sk_lock.slock);
1732 } else {
1733 mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1734 spin_unlock_bh(&sk->sk_lock.slock);
1735 }
1736}
1737
1738void sockopt_lock_sock(struct sock *sk);
1739void sockopt_release_sock(struct sock *sk);
1740bool sockopt_ns_capable(struct user_namespace *ns, int cap);
1741bool sockopt_capable(int cap);
1742
1743/* Used by processes to "lock" a socket state, so that
1744 * interrupts and bottom half handlers won't change it
1745 * from under us. It essentially blocks any incoming
1746 * packets, so that we won't get any new data or any
1747 * packets that change the state of the socket.
1748 *
1749 * While locked, BH processing will add new packets to
1750 * the backlog queue. This queue is processed by the
1751 * owner of the socket lock right before it is released.
1752 *
1753 * Since ~2.3.5 it is also exclusive sleep lock serializing
1754 * accesses from user process context.
1755 */
1756
1757static inline void sock_owned_by_me(const struct sock *sk)
1758{
1759#ifdef CONFIG_LOCKDEP
1760 WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
1761#endif
1762}
1763
1764static inline void sock_not_owned_by_me(const struct sock *sk)
1765{
1766#ifdef CONFIG_LOCKDEP
1767 WARN_ON_ONCE(lockdep_sock_is_held(sk) && debug_locks);
1768#endif
1769}
1770
1771static inline bool sock_owned_by_user(const struct sock *sk)
1772{
1773 sock_owned_by_me(sk);
1774 return sk->sk_lock.owned;
1775}
1776
1777static inline bool sock_owned_by_user_nocheck(const struct sock *sk)
1778{
1779 return sk->sk_lock.owned;
1780}
1781
1782static inline void sock_release_ownership(struct sock *sk)
1783{
1784 DEBUG_NET_WARN_ON_ONCE(!sock_owned_by_user_nocheck(sk));
1785 sk->sk_lock.owned = 0;
1786
1787 /* The sk_lock has mutex_unlock() semantics: */
1788 mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1789}
1790
1791/* no reclassification while locks are held */
1792static inline bool sock_allow_reclassification(const struct sock *csk)
1793{
1794 struct sock *sk = (struct sock *)csk;
1795
1796 return !sock_owned_by_user_nocheck(sk) &&
1797 !spin_is_locked(&sk->sk_lock.slock);
1798}
1799
1800struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1801 struct proto *prot, int kern);
1802void sk_free(struct sock *sk);
1803void sk_destruct(struct sock *sk);
1804struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
1805void sk_free_unlock_clone(struct sock *sk);
1806
1807struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1808 gfp_t priority);
1809void __sock_wfree(struct sk_buff *skb);
1810void sock_wfree(struct sk_buff *skb);
1811struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1812 gfp_t priority);
1813void skb_orphan_partial(struct sk_buff *skb);
1814void sock_rfree(struct sk_buff *skb);
1815void sock_efree(struct sk_buff *skb);
1816#ifdef CONFIG_INET
1817void sock_edemux(struct sk_buff *skb);
1818void sock_pfree(struct sk_buff *skb);
1819#else
1820#define sock_edemux sock_efree
1821#endif
1822
1823int sk_setsockopt(struct sock *sk, int level, int optname,
1824 sockptr_t optval, unsigned int optlen);
1825int sock_setsockopt(struct socket *sock, int level, int op,
1826 sockptr_t optval, unsigned int optlen);
1827int do_sock_setsockopt(struct socket *sock, bool compat, int level,
1828 int optname, sockptr_t optval, int optlen);
1829int do_sock_getsockopt(struct socket *sock, bool compat, int level,
1830 int optname, sockptr_t optval, sockptr_t optlen);
1831
1832int sk_getsockopt(struct sock *sk, int level, int optname,
1833 sockptr_t optval, sockptr_t optlen);
1834int sock_gettstamp(struct socket *sock, void __user *userstamp,
1835 bool timeval, bool time32);
1836struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1837 unsigned long data_len, int noblock,
1838 int *errcode, int max_page_order);
1839
1840static inline struct sk_buff *sock_alloc_send_skb(struct sock *sk,
1841 unsigned long size,
1842 int noblock, int *errcode)
1843{
1844 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
1845}
1846
1847void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
1848void sock_kfree_s(struct sock *sk, void *mem, int size);
1849void sock_kzfree_s(struct sock *sk, void *mem, int size);
1850void sk_send_sigurg(struct sock *sk);
1851
1852static inline void sock_replace_proto(struct sock *sk, struct proto *proto)
1853{
1854 if (sk->sk_socket)
1855 clear_bit(SOCK_SUPPORT_ZC, &sk->sk_socket->flags);
1856 WRITE_ONCE(sk->sk_prot, proto);
1857}
1858
1859struct sockcm_cookie {
1860 u64 transmit_time;
1861 u32 mark;
1862 u32 tsflags;
1863};
1864
1865static inline void sockcm_init(struct sockcm_cookie *sockc,
1866 const struct sock *sk)
1867{
1868 *sockc = (struct sockcm_cookie) {
1869 .tsflags = READ_ONCE(sk->sk_tsflags)
1870 };
1871}
1872
1873int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
1874 struct sockcm_cookie *sockc);
1875int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1876 struct sockcm_cookie *sockc);
1877
1878/*
1879 * Functions to fill in entries in struct proto_ops when a protocol
1880 * does not implement a particular function.
1881 */
1882int sock_no_bind(struct socket *, struct sockaddr *, int);
1883int sock_no_connect(struct socket *, struct sockaddr *, int, int);
1884int sock_no_socketpair(struct socket *, struct socket *);
1885int sock_no_accept(struct socket *, struct socket *, int, bool);
1886int sock_no_getname(struct socket *, struct sockaddr *, int);
1887int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
1888int sock_no_listen(struct socket *, int);
1889int sock_no_shutdown(struct socket *, int);
1890int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
1891int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
1892int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
1893int sock_no_mmap(struct file *file, struct socket *sock,
1894 struct vm_area_struct *vma);
1895
1896/*
1897 * Functions to fill in entries in struct proto_ops when a protocol
1898 * uses the inet style.
1899 */
1900int sock_common_getsockopt(struct socket *sock, int level, int optname,
1901 char __user *optval, int __user *optlen);
1902int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1903 int flags);
1904int sock_common_setsockopt(struct socket *sock, int level, int optname,
1905 sockptr_t optval, unsigned int optlen);
1906
1907void sk_common_release(struct sock *sk);
1908
1909/*
1910 * Default socket callbacks and setup code
1911 */
1912
1913/* Initialise core socket variables using an explicit uid. */
1914void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid);
1915
1916/* Initialise core socket variables.
1917 * Assumes struct socket *sock is embedded in a struct socket_alloc.
1918 */
1919void sock_init_data(struct socket *sock, struct sock *sk);
1920
1921/*
1922 * Socket reference counting postulates.
1923 *
1924 * * Each user of socket SHOULD hold a reference count.
1925 * * Each access point to socket (an hash table bucket, reference from a list,
1926 * running timer, skb in flight MUST hold a reference count.
1927 * * When reference count hits 0, it means it will never increase back.
1928 * * When reference count hits 0, it means that no references from
1929 * outside exist to this socket and current process on current CPU
1930 * is last user and may/should destroy this socket.
1931 * * sk_free is called from any context: process, BH, IRQ. When
1932 * it is called, socket has no references from outside -> sk_free
1933 * may release descendant resources allocated by the socket, but
1934 * to the time when it is called, socket is NOT referenced by any
1935 * hash tables, lists etc.
1936 * * Packets, delivered from outside (from network or from another process)
1937 * and enqueued on receive/error queues SHOULD NOT grab reference count,
1938 * when they sit in queue. Otherwise, packets will leak to hole, when
1939 * socket is looked up by one cpu and unhasing is made by another CPU.
1940 * It is true for udp/raw, netlink (leak to receive and error queues), tcp
1941 * (leak to backlog). Packet socket does all the processing inside
1942 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1943 * use separate SMP lock, so that they are prone too.
1944 */
1945
1946/* Ungrab socket and destroy it, if it was the last reference. */
1947static inline void sock_put(struct sock *sk)
1948{
1949 if (refcount_dec_and_test(&sk->sk_refcnt))
1950 sk_free(sk);
1951}
1952/* Generic version of sock_put(), dealing with all sockets
1953 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
1954 */
1955void sock_gen_put(struct sock *sk);
1956
1957int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested,
1958 unsigned int trim_cap, bool refcounted);
1959static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1960 const int nested)
1961{
1962 return __sk_receive_skb(sk, skb, nested, 1, true);
1963}
1964
1965static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1966{
1967 /* sk_tx_queue_mapping accept only upto a 16-bit value */
1968 if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX))
1969 return;
1970 /* Paired with READ_ONCE() in sk_tx_queue_get() and
1971 * other WRITE_ONCE() because socket lock might be not held.
1972 */
1973 WRITE_ONCE(sk->sk_tx_queue_mapping, tx_queue);
1974}
1975
1976#define NO_QUEUE_MAPPING USHRT_MAX
1977
1978static inline void sk_tx_queue_clear(struct sock *sk)
1979{
1980 /* Paired with READ_ONCE() in sk_tx_queue_get() and
1981 * other WRITE_ONCE() because socket lock might be not held.
1982 */
1983 WRITE_ONCE(sk->sk_tx_queue_mapping, NO_QUEUE_MAPPING);
1984}
1985
1986static inline int sk_tx_queue_get(const struct sock *sk)
1987{
1988 if (sk) {
1989 /* Paired with WRITE_ONCE() in sk_tx_queue_clear()
1990 * and sk_tx_queue_set().
1991 */
1992 int val = READ_ONCE(sk->sk_tx_queue_mapping);
1993
1994 if (val != NO_QUEUE_MAPPING)
1995 return val;
1996 }
1997 return -1;
1998}
1999
2000static inline void __sk_rx_queue_set(struct sock *sk,
2001 const struct sk_buff *skb,
2002 bool force_set)
2003{
2004#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
2005 if (skb_rx_queue_recorded(skb)) {
2006 u16 rx_queue = skb_get_rx_queue(skb);
2007
2008 if (force_set ||
2009 unlikely(READ_ONCE(sk->sk_rx_queue_mapping) != rx_queue))
2010 WRITE_ONCE(sk->sk_rx_queue_mapping, rx_queue);
2011 }
2012#endif
2013}
2014
2015static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb)
2016{
2017 __sk_rx_queue_set(sk, skb, true);
2018}
2019
2020static inline void sk_rx_queue_update(struct sock *sk, const struct sk_buff *skb)
2021{
2022 __sk_rx_queue_set(sk, skb, false);
2023}
2024
2025static inline void sk_rx_queue_clear(struct sock *sk)
2026{
2027#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
2028 WRITE_ONCE(sk->sk_rx_queue_mapping, NO_QUEUE_MAPPING);
2029#endif
2030}
2031
2032static inline int sk_rx_queue_get(const struct sock *sk)
2033{
2034#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
2035 if (sk) {
2036 int res = READ_ONCE(sk->sk_rx_queue_mapping);
2037
2038 if (res != NO_QUEUE_MAPPING)
2039 return res;
2040 }
2041#endif
2042
2043 return -1;
2044}
2045
2046static inline void sk_set_socket(struct sock *sk, struct socket *sock)
2047{
2048 sk->sk_socket = sock;
2049}
2050
2051static inline wait_queue_head_t *sk_sleep(struct sock *sk)
2052{
2053 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
2054 return &rcu_dereference_raw(sk->sk_wq)->wait;
2055}
2056/* Detach socket from process context.
2057 * Announce socket dead, detach it from wait queue and inode.
2058 * Note that parent inode held reference count on this struct sock,
2059 * we do not release it in this function, because protocol
2060 * probably wants some additional cleanups or even continuing
2061 * to work with this socket (TCP).
2062 */
2063static inline void sock_orphan(struct sock *sk)
2064{
2065 write_lock_bh(&sk->sk_callback_lock);
2066 sock_set_flag(sk, SOCK_DEAD);
2067 sk_set_socket(sk, NULL);
2068 sk->sk_wq = NULL;
2069 write_unlock_bh(&sk->sk_callback_lock);
2070}
2071
2072static inline void sock_graft(struct sock *sk, struct socket *parent)
2073{
2074 WARN_ON(parent->sk);
2075 write_lock_bh(&sk->sk_callback_lock);
2076 rcu_assign_pointer(sk->sk_wq, &parent->wq);
2077 parent->sk = sk;
2078 sk_set_socket(sk, parent);
2079 sk->sk_uid = SOCK_INODE(parent)->i_uid;
2080 security_sock_graft(sk, parent);
2081 write_unlock_bh(&sk->sk_callback_lock);
2082}
2083
2084kuid_t sock_i_uid(struct sock *sk);
2085unsigned long __sock_i_ino(struct sock *sk);
2086unsigned long sock_i_ino(struct sock *sk);
2087
2088static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk)
2089{
2090 return sk ? sk->sk_uid : make_kuid(net->user_ns, 0);
2091}
2092
2093static inline u32 net_tx_rndhash(void)
2094{
2095 u32 v = get_random_u32();
2096
2097 return v ?: 1;
2098}
2099
2100static inline void sk_set_txhash(struct sock *sk)
2101{
2102 /* This pairs with READ_ONCE() in skb_set_hash_from_sk() */
2103 WRITE_ONCE(sk->sk_txhash, net_tx_rndhash());
2104}
2105
2106static inline bool sk_rethink_txhash(struct sock *sk)
2107{
2108 if (sk->sk_txhash && sk->sk_txrehash == SOCK_TXREHASH_ENABLED) {
2109 sk_set_txhash(sk);
2110 return true;
2111 }
2112 return false;
2113}
2114
2115static inline struct dst_entry *
2116__sk_dst_get(const struct sock *sk)
2117{
2118 return rcu_dereference_check(sk->sk_dst_cache,
2119 lockdep_sock_is_held(sk));
2120}
2121
2122static inline struct dst_entry *
2123sk_dst_get(const struct sock *sk)
2124{
2125 struct dst_entry *dst;
2126
2127 rcu_read_lock();
2128 dst = rcu_dereference(sk->sk_dst_cache);
2129 if (dst && !rcuref_get(&dst->__rcuref))
2130 dst = NULL;
2131 rcu_read_unlock();
2132 return dst;
2133}
2134
2135static inline void __dst_negative_advice(struct sock *sk)
2136{
2137 struct dst_entry *dst = __sk_dst_get(sk);
2138
2139 if (dst && dst->ops->negative_advice)
2140 dst->ops->negative_advice(sk, dst);
2141}
2142
2143static inline void dst_negative_advice(struct sock *sk)
2144{
2145 sk_rethink_txhash(sk);
2146 __dst_negative_advice(sk);
2147}
2148
2149static inline void
2150__sk_dst_set(struct sock *sk, struct dst_entry *dst)
2151{
2152 struct dst_entry *old_dst;
2153
2154 sk_tx_queue_clear(sk);
2155 WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2156 old_dst = rcu_dereference_protected(sk->sk_dst_cache,
2157 lockdep_sock_is_held(sk));
2158 rcu_assign_pointer(sk->sk_dst_cache, dst);
2159 dst_release(old_dst);
2160}
2161
2162static inline void
2163sk_dst_set(struct sock *sk, struct dst_entry *dst)
2164{
2165 struct dst_entry *old_dst;
2166
2167 sk_tx_queue_clear(sk);
2168 WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2169 old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst);
2170 dst_release(old_dst);
2171}
2172
2173static inline void
2174__sk_dst_reset(struct sock *sk)
2175{
2176 __sk_dst_set(sk, NULL);
2177}
2178
2179static inline void
2180sk_dst_reset(struct sock *sk)
2181{
2182 sk_dst_set(sk, NULL);
2183}
2184
2185struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
2186
2187struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
2188
2189static inline void sk_dst_confirm(struct sock *sk)
2190{
2191 if (!READ_ONCE(sk->sk_dst_pending_confirm))
2192 WRITE_ONCE(sk->sk_dst_pending_confirm, 1);
2193}
2194
2195static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n)
2196{
2197 if (skb_get_dst_pending_confirm(skb)) {
2198 struct sock *sk = skb->sk;
2199
2200 if (sk && READ_ONCE(sk->sk_dst_pending_confirm))
2201 WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2202 neigh_confirm(n);
2203 }
2204}
2205
2206bool sk_mc_loop(const struct sock *sk);
2207
2208static inline bool sk_can_gso(const struct sock *sk)
2209{
2210 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
2211}
2212
2213void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
2214
2215static inline void sk_gso_disable(struct sock *sk)
2216{
2217 sk->sk_gso_disabled = 1;
2218 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2219}
2220
2221static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
2222 struct iov_iter *from, char *to,
2223 int copy, int offset)
2224{
2225 if (skb->ip_summed == CHECKSUM_NONE) {
2226 __wsum csum = 0;
2227 if (!csum_and_copy_from_iter_full(to, copy, &csum, from))
2228 return -EFAULT;
2229 skb->csum = csum_block_add(skb->csum, csum, offset);
2230 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
2231 if (!copy_from_iter_full_nocache(to, copy, from))
2232 return -EFAULT;
2233 } else if (!copy_from_iter_full(to, copy, from))
2234 return -EFAULT;
2235
2236 return 0;
2237}
2238
2239static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
2240 struct iov_iter *from, int copy)
2241{
2242 int err, offset = skb->len;
2243
2244 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
2245 copy, offset);
2246 if (err)
2247 __skb_trim(skb, offset);
2248
2249 return err;
2250}
2251
2252static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
2253 struct sk_buff *skb,
2254 struct page *page,
2255 int off, int copy)
2256{
2257 int err;
2258
2259 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
2260 copy, skb->len);
2261 if (err)
2262 return err;
2263
2264 skb_len_add(skb, copy);
2265 sk_wmem_queued_add(sk, copy);
2266 sk_mem_charge(sk, copy);
2267 return 0;
2268}
2269
2270/**
2271 * sk_wmem_alloc_get - returns write allocations
2272 * @sk: socket
2273 *
2274 * Return: sk_wmem_alloc minus initial offset of one
2275 */
2276static inline int sk_wmem_alloc_get(const struct sock *sk)
2277{
2278 return refcount_read(&sk->sk_wmem_alloc) - 1;
2279}
2280
2281/**
2282 * sk_rmem_alloc_get - returns read allocations
2283 * @sk: socket
2284 *
2285 * Return: sk_rmem_alloc
2286 */
2287static inline int sk_rmem_alloc_get(const struct sock *sk)
2288{
2289 return atomic_read(&sk->sk_rmem_alloc);
2290}
2291
2292/**
2293 * sk_has_allocations - check if allocations are outstanding
2294 * @sk: socket
2295 *
2296 * Return: true if socket has write or read allocations
2297 */
2298static inline bool sk_has_allocations(const struct sock *sk)
2299{
2300 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
2301}
2302
2303/**
2304 * skwq_has_sleeper - check if there are any waiting processes
2305 * @wq: struct socket_wq
2306 *
2307 * Return: true if socket_wq has waiting processes
2308 *
2309 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory
2310 * barrier call. They were added due to the race found within the tcp code.
2311 *
2312 * Consider following tcp code paths::
2313 *
2314 * CPU1 CPU2
2315 * sys_select receive packet
2316 * ... ...
2317 * __add_wait_queue update tp->rcv_nxt
2318 * ... ...
2319 * tp->rcv_nxt check sock_def_readable
2320 * ... {
2321 * schedule rcu_read_lock();
2322 * wq = rcu_dereference(sk->sk_wq);
2323 * if (wq && waitqueue_active(&wq->wait))
2324 * wake_up_interruptible(&wq->wait)
2325 * ...
2326 * }
2327 *
2328 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
2329 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1
2330 * could then endup calling schedule and sleep forever if there are no more
2331 * data on the socket.
2332 *
2333 */
2334static inline bool skwq_has_sleeper(struct socket_wq *wq)
2335{
2336 return wq && wq_has_sleeper(&wq->wait);
2337}
2338
2339/**
2340 * sock_poll_wait - place memory barrier behind the poll_wait call.
2341 * @filp: file
2342 * @sock: socket to wait on
2343 * @p: poll_table
2344 *
2345 * See the comments in the wq_has_sleeper function.
2346 */
2347static inline void sock_poll_wait(struct file *filp, struct socket *sock,
2348 poll_table *p)
2349{
2350 if (!poll_does_not_wait(p)) {
2351 poll_wait(filp, &sock->wq.wait, p);
2352 /* We need to be sure we are in sync with the
2353 * socket flags modification.
2354 *
2355 * This memory barrier is paired in the wq_has_sleeper.
2356 */
2357 smp_mb();
2358 }
2359}
2360
2361static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk)
2362{
2363 /* This pairs with WRITE_ONCE() in sk_set_txhash() */
2364 u32 txhash = READ_ONCE(sk->sk_txhash);
2365
2366 if (txhash) {
2367 skb->l4_hash = 1;
2368 skb->hash = txhash;
2369 }
2370}
2371
2372void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);
2373
2374/*
2375 * Queue a received datagram if it will fit. Stream and sequenced
2376 * protocols can't normally use this as they need to fit buffers in
2377 * and play with them.
2378 *
2379 * Inlined as it's very short and called for pretty much every
2380 * packet ever received.
2381 */
2382static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
2383{
2384 skb_orphan(skb);
2385 skb->sk = sk;
2386 skb->destructor = sock_rfree;
2387 atomic_add(skb->truesize, &sk->sk_rmem_alloc);
2388 sk_mem_charge(sk, skb->truesize);
2389}
2390
2391static inline __must_check bool skb_set_owner_sk_safe(struct sk_buff *skb, struct sock *sk)
2392{
2393 if (sk && refcount_inc_not_zero(&sk->sk_refcnt)) {
2394 skb_orphan(skb);
2395 skb->destructor = sock_efree;
2396 skb->sk = sk;
2397 return true;
2398 }
2399 return false;
2400}
2401
2402static inline struct sk_buff *skb_clone_and_charge_r(struct sk_buff *skb, struct sock *sk)
2403{
2404 skb = skb_clone(skb, sk_gfp_mask(sk, GFP_ATOMIC));
2405 if (skb) {
2406 if (sk_rmem_schedule(sk, skb, skb->truesize)) {
2407 skb_set_owner_r(skb, sk);
2408 return skb;
2409 }
2410 __kfree_skb(skb);
2411 }
2412 return NULL;
2413}
2414
2415static inline void skb_prepare_for_gro(struct sk_buff *skb)
2416{
2417 if (skb->destructor != sock_wfree) {
2418 skb_orphan(skb);
2419 return;
2420 }
2421 skb->slow_gro = 1;
2422}
2423
2424void sk_reset_timer(struct sock *sk, struct timer_list *timer,
2425 unsigned long expires);
2426
2427void sk_stop_timer(struct sock *sk, struct timer_list *timer);
2428
2429void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer);
2430
2431int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue,
2432 struct sk_buff *skb, unsigned int flags,
2433 void (*destructor)(struct sock *sk,
2434 struct sk_buff *skb));
2435int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2436
2437int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb,
2438 enum skb_drop_reason *reason);
2439
2440static inline int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
2441{
2442 return sock_queue_rcv_skb_reason(sk, skb, NULL);
2443}
2444
2445int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2446struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
2447
2448/*
2449 * Recover an error report and clear atomically
2450 */
2451
2452static inline int sock_error(struct sock *sk)
2453{
2454 int err;
2455
2456 /* Avoid an atomic operation for the common case.
2457 * This is racy since another cpu/thread can change sk_err under us.
2458 */
2459 if (likely(data_race(!sk->sk_err)))
2460 return 0;
2461
2462 err = xchg(&sk->sk_err, 0);
2463 return -err;
2464}
2465
2466void sk_error_report(struct sock *sk);
2467
2468static inline unsigned long sock_wspace(struct sock *sk)
2469{
2470 int amt = 0;
2471
2472 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2473 amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc);
2474 if (amt < 0)
2475 amt = 0;
2476 }
2477 return amt;
2478}
2479
2480/* Note:
2481 * We use sk->sk_wq_raw, from contexts knowing this
2482 * pointer is not NULL and cannot disappear/change.
2483 */
2484static inline void sk_set_bit(int nr, struct sock *sk)
2485{
2486 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2487 !sock_flag(sk, SOCK_FASYNC))
2488 return;
2489
2490 set_bit(nr, &sk->sk_wq_raw->flags);
2491}
2492
2493static inline void sk_clear_bit(int nr, struct sock *sk)
2494{
2495 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2496 !sock_flag(sk, SOCK_FASYNC))
2497 return;
2498
2499 clear_bit(nr, &sk->sk_wq_raw->flags);
2500}
2501
2502static inline void sk_wake_async(const struct sock *sk, int how, int band)
2503{
2504 if (sock_flag(sk, SOCK_FASYNC)) {
2505 rcu_read_lock();
2506 sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2507 rcu_read_unlock();
2508 }
2509}
2510
2511/* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2512 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2513 * Note: for send buffers, TCP works better if we can build two skbs at
2514 * minimum.
2515 */
2516#define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2517
2518#define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2)
2519#define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE
2520
2521static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2522{
2523 u32 val;
2524
2525 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)
2526 return;
2527
2528 val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2529 val = max_t(u32, val, sk_unused_reserved_mem(sk));
2530
2531 WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF));
2532}
2533
2534/**
2535 * sk_page_frag - return an appropriate page_frag
2536 * @sk: socket
2537 *
2538 * Use the per task page_frag instead of the per socket one for
2539 * optimization when we know that we're in process context and own
2540 * everything that's associated with %current.
2541 *
2542 * Both direct reclaim and page faults can nest inside other
2543 * socket operations and end up recursing into sk_page_frag()
2544 * while it's already in use: explicitly avoid task page_frag
2545 * when users disable sk_use_task_frag.
2546 *
2547 * Return: a per task page_frag if context allows that,
2548 * otherwise a per socket one.
2549 */
2550static inline struct page_frag *sk_page_frag(struct sock *sk)
2551{
2552 if (sk->sk_use_task_frag)
2553 return ¤t->task_frag;
2554
2555 return &sk->sk_frag;
2556}
2557
2558bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2559
2560/*
2561 * Default write policy as shown to user space via poll/select/SIGIO
2562 */
2563static inline bool sock_writeable(const struct sock *sk)
2564{
2565 return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1);
2566}
2567
2568static inline gfp_t gfp_any(void)
2569{
2570 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2571}
2572
2573static inline gfp_t gfp_memcg_charge(void)
2574{
2575 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2576}
2577
2578static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2579{
2580 return noblock ? 0 : sk->sk_rcvtimeo;
2581}
2582
2583static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2584{
2585 return noblock ? 0 : sk->sk_sndtimeo;
2586}
2587
2588static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2589{
2590 int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len);
2591
2592 return v ?: 1;
2593}
2594
2595/* Alas, with timeout socket operations are not restartable.
2596 * Compare this to poll().
2597 */
2598static inline int sock_intr_errno(long timeo)
2599{
2600 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2601}
2602
2603struct sock_skb_cb {
2604 u32 dropcount;
2605};
2606
2607/* Store sock_skb_cb at the end of skb->cb[] so protocol families
2608 * using skb->cb[] would keep using it directly and utilize its
2609 * alignement guarantee.
2610 */
2611#define SOCK_SKB_CB_OFFSET ((sizeof_field(struct sk_buff, cb) - \
2612 sizeof(struct sock_skb_cb)))
2613
2614#define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
2615 SOCK_SKB_CB_OFFSET))
2616
2617#define sock_skb_cb_check_size(size) \
2618 BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
2619
2620static inline void
2621sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
2622{
2623 SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ?
2624 atomic_read(&sk->sk_drops) : 0;
2625}
2626
2627static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb)
2628{
2629 int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs);
2630
2631 atomic_add(segs, &sk->sk_drops);
2632}
2633
2634static inline ktime_t sock_read_timestamp(struct sock *sk)
2635{
2636#if BITS_PER_LONG==32
2637 unsigned int seq;
2638 ktime_t kt;
2639
2640 do {
2641 seq = read_seqbegin(&sk->sk_stamp_seq);
2642 kt = sk->sk_stamp;
2643 } while (read_seqretry(&sk->sk_stamp_seq, seq));
2644
2645 return kt;
2646#else
2647 return READ_ONCE(sk->sk_stamp);
2648#endif
2649}
2650
2651static inline void sock_write_timestamp(struct sock *sk, ktime_t kt)
2652{
2653#if BITS_PER_LONG==32
2654 write_seqlock(&sk->sk_stamp_seq);
2655 sk->sk_stamp = kt;
2656 write_sequnlock(&sk->sk_stamp_seq);
2657#else
2658 WRITE_ONCE(sk->sk_stamp, kt);
2659#endif
2660}
2661
2662void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2663 struct sk_buff *skb);
2664void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2665 struct sk_buff *skb);
2666
2667static inline void
2668sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2669{
2670 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2671 u32 tsflags = READ_ONCE(sk->sk_tsflags);
2672 ktime_t kt = skb->tstamp;
2673 /*
2674 * generate control messages if
2675 * - receive time stamping in software requested
2676 * - software time stamp available and wanted
2677 * - hardware time stamps available and wanted
2678 */
2679 if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2680 (tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
2681 (kt && tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
2682 (hwtstamps->hwtstamp &&
2683 (tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
2684 __sock_recv_timestamp(msg, sk, skb);
2685 else
2686 sock_write_timestamp(sk, kt);
2687
2688 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb_wifi_acked_valid(skb))
2689 __sock_recv_wifi_status(msg, sk, skb);
2690}
2691
2692void __sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
2693 struct sk_buff *skb);
2694
2695#define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC)
2696static inline void sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
2697 struct sk_buff *skb)
2698{
2699#define FLAGS_RECV_CMSGS ((1UL << SOCK_RXQ_OVFL) | \
2700 (1UL << SOCK_RCVTSTAMP) | \
2701 (1UL << SOCK_RCVMARK))
2702#define TSFLAGS_ANY (SOF_TIMESTAMPING_SOFTWARE | \
2703 SOF_TIMESTAMPING_RAW_HARDWARE)
2704
2705 if (sk->sk_flags & FLAGS_RECV_CMSGS ||
2706 READ_ONCE(sk->sk_tsflags) & TSFLAGS_ANY)
2707 __sock_recv_cmsgs(msg, sk, skb);
2708 else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP)))
2709 sock_write_timestamp(sk, skb->tstamp);
2710 else if (unlikely(sock_read_timestamp(sk) == SK_DEFAULT_STAMP))
2711 sock_write_timestamp(sk, 0);
2712}
2713
2714void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags);
2715
2716/**
2717 * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2718 * @sk: socket sending this packet
2719 * @tsflags: timestamping flags to use
2720 * @tx_flags: completed with instructions for time stamping
2721 * @tskey: filled in with next sk_tskey (not for TCP, which uses seqno)
2722 *
2723 * Note: callers should take care of initial ``*tx_flags`` value (usually 0)
2724 */
2725static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2726 __u8 *tx_flags, __u32 *tskey)
2727{
2728 if (unlikely(tsflags)) {
2729 __sock_tx_timestamp(tsflags, tx_flags);
2730 if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey &&
2731 tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK)
2732 *tskey = atomic_inc_return(&sk->sk_tskey) - 1;
2733 }
2734 if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
2735 *tx_flags |= SKBTX_WIFI_STATUS;
2736}
2737
2738static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2739 __u8 *tx_flags)
2740{
2741 _sock_tx_timestamp(sk, tsflags, tx_flags, NULL);
2742}
2743
2744static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags)
2745{
2746 _sock_tx_timestamp(skb->sk, tsflags, &skb_shinfo(skb)->tx_flags,
2747 &skb_shinfo(skb)->tskey);
2748}
2749
2750static inline bool sk_is_inet(const struct sock *sk)
2751{
2752 int family = READ_ONCE(sk->sk_family);
2753
2754 return family == AF_INET || family == AF_INET6;
2755}
2756
2757static inline bool sk_is_tcp(const struct sock *sk)
2758{
2759 return sk_is_inet(sk) &&
2760 sk->sk_type == SOCK_STREAM &&
2761 sk->sk_protocol == IPPROTO_TCP;
2762}
2763
2764static inline bool sk_is_udp(const struct sock *sk)
2765{
2766 return sk_is_inet(sk) &&
2767 sk->sk_type == SOCK_DGRAM &&
2768 sk->sk_protocol == IPPROTO_UDP;
2769}
2770
2771static inline bool sk_is_stream_unix(const struct sock *sk)
2772{
2773 return sk->sk_family == AF_UNIX && sk->sk_type == SOCK_STREAM;
2774}
2775
2776/**
2777 * sk_eat_skb - Release a skb if it is no longer needed
2778 * @sk: socket to eat this skb from
2779 * @skb: socket buffer to eat
2780 *
2781 * This routine must be called with interrupts disabled or with the socket
2782 * locked so that the sk_buff queue operation is ok.
2783*/
2784static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
2785{
2786 __skb_unlink(skb, &sk->sk_receive_queue);
2787 __kfree_skb(skb);
2788}
2789
2790static inline bool
2791skb_sk_is_prefetched(struct sk_buff *skb)
2792{
2793#ifdef CONFIG_INET
2794 return skb->destructor == sock_pfree;
2795#else
2796 return false;
2797#endif /* CONFIG_INET */
2798}
2799
2800/* This helper checks if a socket is a full socket,
2801 * ie _not_ a timewait or request socket.
2802 */
2803static inline bool sk_fullsock(const struct sock *sk)
2804{
2805 return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
2806}
2807
2808static inline bool
2809sk_is_refcounted(struct sock *sk)
2810{
2811 /* Only full sockets have sk->sk_flags. */
2812 return !sk_fullsock(sk) || !sock_flag(sk, SOCK_RCU_FREE);
2813}
2814
2815/* Checks if this SKB belongs to an HW offloaded socket
2816 * and whether any SW fallbacks are required based on dev.
2817 * Check decrypted mark in case skb_orphan() cleared socket.
2818 */
2819static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb,
2820 struct net_device *dev)
2821{
2822#ifdef CONFIG_SOCK_VALIDATE_XMIT
2823 struct sock *sk = skb->sk;
2824
2825 if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) {
2826 skb = sk->sk_validate_xmit_skb(sk, dev, skb);
2827#ifdef CONFIG_TLS_DEVICE
2828 } else if (unlikely(skb->decrypted)) {
2829 pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n");
2830 kfree_skb(skb);
2831 skb = NULL;
2832#endif
2833 }
2834#endif
2835
2836 return skb;
2837}
2838
2839/* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
2840 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
2841 */
2842static inline bool sk_listener(const struct sock *sk)
2843{
2844 return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
2845}
2846
2847void sock_enable_timestamp(struct sock *sk, enum sock_flags flag);
2848int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
2849 int type);
2850
2851bool sk_ns_capable(const struct sock *sk,
2852 struct user_namespace *user_ns, int cap);
2853bool sk_capable(const struct sock *sk, int cap);
2854bool sk_net_capable(const struct sock *sk, int cap);
2855
2856void sk_get_meminfo(const struct sock *sk, u32 *meminfo);
2857
2858/* Take into consideration the size of the struct sk_buff overhead in the
2859 * determination of these values, since that is non-constant across
2860 * platforms. This makes socket queueing behavior and performance
2861 * not depend upon such differences.
2862 */
2863#define _SK_MEM_PACKETS 256
2864#define _SK_MEM_OVERHEAD SKB_TRUESIZE(256)
2865#define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2866#define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2867
2868extern __u32 sysctl_wmem_max;
2869extern __u32 sysctl_rmem_max;
2870
2871extern int sysctl_tstamp_allow_data;
2872
2873extern __u32 sysctl_wmem_default;
2874extern __u32 sysctl_rmem_default;
2875
2876#define SKB_FRAG_PAGE_ORDER get_order(32768)
2877DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2878
2879static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto)
2880{
2881 /* Does this proto have per netns sysctl_wmem ? */
2882 if (proto->sysctl_wmem_offset)
2883 return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset));
2884
2885 return READ_ONCE(*proto->sysctl_wmem);
2886}
2887
2888static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto)
2889{
2890 /* Does this proto have per netns sysctl_rmem ? */
2891 if (proto->sysctl_rmem_offset)
2892 return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset));
2893
2894 return READ_ONCE(*proto->sysctl_rmem);
2895}
2896
2897/* Default TCP Small queue budget is ~1 ms of data (1sec >> 10)
2898 * Some wifi drivers need to tweak it to get more chunks.
2899 * They can use this helper from their ndo_start_xmit()
2900 */
2901static inline void sk_pacing_shift_update(struct sock *sk, int val)
2902{
2903 if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val)
2904 return;
2905 WRITE_ONCE(sk->sk_pacing_shift, val);
2906}
2907
2908/* if a socket is bound to a device, check that the given device
2909 * index is either the same or that the socket is bound to an L3
2910 * master device and the given device index is also enslaved to
2911 * that L3 master
2912 */
2913static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif)
2914{
2915 int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
2916 int mdif;
2917
2918 if (!bound_dev_if || bound_dev_if == dif)
2919 return true;
2920
2921 mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif);
2922 if (mdif && mdif == bound_dev_if)
2923 return true;
2924
2925 return false;
2926}
2927
2928void sock_def_readable(struct sock *sk);
2929
2930int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk);
2931void sock_set_timestamp(struct sock *sk, int optname, bool valbool);
2932int sock_set_timestamping(struct sock *sk, int optname,
2933 struct so_timestamping timestamping);
2934
2935void sock_enable_timestamps(struct sock *sk);
2936void sock_no_linger(struct sock *sk);
2937void sock_set_keepalive(struct sock *sk);
2938void sock_set_priority(struct sock *sk, u32 priority);
2939void sock_set_rcvbuf(struct sock *sk, int val);
2940void sock_set_mark(struct sock *sk, u32 val);
2941void sock_set_reuseaddr(struct sock *sk);
2942void sock_set_reuseport(struct sock *sk);
2943void sock_set_sndtimeo(struct sock *sk, s64 secs);
2944
2945int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len);
2946
2947int sock_get_timeout(long timeo, void *optval, bool old_timeval);
2948int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
2949 sockptr_t optval, int optlen, bool old_timeval);
2950
2951int sock_ioctl_inout(struct sock *sk, unsigned int cmd,
2952 void __user *arg, void *karg, size_t size);
2953int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg);
2954static inline bool sk_is_readable(struct sock *sk)
2955{
2956 if (sk->sk_prot->sock_is_readable)
2957 return sk->sk_prot->sock_is_readable(sk);
2958 return false;
2959}
2960#endif /* _SOCK_H */