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/filter.h>
60 #include <linux/rculist_nulls.h>
61 #include <linux/poll.h>
62 #include <linux/sockptr.h>
63 #include <linux/indirect_call_wrapper.h>
64 #include <linux/atomic.h>
65 #include <linux/refcount.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
72 /*
73 * This structure really needs to be cleaned up.
74 * Most of it is for TCP, and not used by any of
75 * the other protocols.
76 */
77
78 /* Define this to get the SOCK_DBG debugging facility. */
79 #define SOCK_DEBUGGING
80 #ifdef SOCK_DEBUGGING
81 #define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
82 printk(KERN_DEBUG msg); } while (0)
83 #else
84 /* Validate arguments and do nothing */
85 static inline __printf(2, 3)
SOCK_DEBUG(const struct sock * sk,const char * msg,...)86 void SOCK_DEBUG(const struct sock *sk, const char *msg, ...)
87 {
88 }
89 #endif
90
91 /* This is the per-socket lock. The spinlock provides a synchronization
92 * between user contexts and software interrupt processing, whereas the
93 * mini-semaphore synchronizes multiple users amongst themselves.
94 */
95 typedef struct {
96 spinlock_t slock;
97 int owned;
98 wait_queue_head_t wq;
99 /*
100 * We express the mutex-alike socket_lock semantics
101 * to the lock validator by explicitly managing
102 * the slock as a lock variant (in addition to
103 * the slock itself):
104 */
105 #ifdef CONFIG_DEBUG_LOCK_ALLOC
106 struct lockdep_map dep_map;
107 #endif
108 } socket_lock_t;
109
110 struct sock;
111 struct proto;
112 struct net;
113
114 typedef __u32 __bitwise __portpair;
115 typedef __u64 __bitwise __addrpair;
116
117 /**
118 * struct sock_common - minimal network layer representation of sockets
119 * @skc_daddr: Foreign IPv4 addr
120 * @skc_rcv_saddr: Bound local IPv4 addr
121 * @skc_addrpair: 8-byte-aligned __u64 union of @skc_daddr & @skc_rcv_saddr
122 * @skc_hash: hash value used with various protocol lookup tables
123 * @skc_u16hashes: two u16 hash values used by UDP lookup tables
124 * @skc_dport: placeholder for inet_dport/tw_dport
125 * @skc_num: placeholder for inet_num/tw_num
126 * @skc_portpair: __u32 union of @skc_dport & @skc_num
127 * @skc_family: network address family
128 * @skc_state: Connection state
129 * @skc_reuse: %SO_REUSEADDR setting
130 * @skc_reuseport: %SO_REUSEPORT setting
131 * @skc_ipv6only: socket is IPV6 only
132 * @skc_net_refcnt: socket is using net ref counting
133 * @skc_bound_dev_if: bound device index if != 0
134 * @skc_bind_node: bind hash linkage for various protocol lookup tables
135 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
136 * @skc_prot: protocol handlers inside a network family
137 * @skc_net: reference to the network namespace of this socket
138 * @skc_v6_daddr: IPV6 destination address
139 * @skc_v6_rcv_saddr: IPV6 source address
140 * @skc_cookie: socket's cookie value
141 * @skc_node: main hash linkage for various protocol lookup tables
142 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
143 * @skc_tx_queue_mapping: tx queue number for this connection
144 * @skc_rx_queue_mapping: rx queue number for this connection
145 * @skc_flags: place holder for sk_flags
146 * %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
147 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings
148 * @skc_listener: connection request listener socket (aka rsk_listener)
149 * [union with @skc_flags]
150 * @skc_tw_dr: (aka tw_dr) ptr to &struct inet_timewait_death_row
151 * [union with @skc_flags]
152 * @skc_incoming_cpu: record/match cpu processing incoming packets
153 * @skc_rcv_wnd: (aka rsk_rcv_wnd) TCP receive window size (possibly scaled)
154 * [union with @skc_incoming_cpu]
155 * @skc_tw_rcv_nxt: (aka tw_rcv_nxt) TCP window next expected seq number
156 * [union with @skc_incoming_cpu]
157 * @skc_refcnt: reference count
158 *
159 * This is the minimal network layer representation of sockets, the header
160 * for struct sock and struct inet_timewait_sock.
161 */
162 struct sock_common {
163 /* skc_daddr and skc_rcv_saddr must be grouped on a 8 bytes aligned
164 * address on 64bit arches : cf INET_MATCH()
165 */
166 union {
167 __addrpair skc_addrpair;
168 struct {
169 __be32 skc_daddr;
170 __be32 skc_rcv_saddr;
171 };
172 };
173 union {
174 unsigned int skc_hash;
175 __u16 skc_u16hashes[2];
176 };
177 /* skc_dport && skc_num must be grouped as well */
178 union {
179 __portpair skc_portpair;
180 struct {
181 __be16 skc_dport;
182 __u16 skc_num;
183 };
184 };
185
186 unsigned short skc_family;
187 volatile unsigned char skc_state;
188 unsigned char skc_reuse:4;
189 unsigned char skc_reuseport:1;
190 unsigned char skc_ipv6only:1;
191 unsigned char skc_net_refcnt:1;
192 int skc_bound_dev_if;
193 union {
194 struct hlist_node skc_bind_node;
195 struct hlist_node skc_portaddr_node;
196 };
197 struct proto *skc_prot;
198 possible_net_t skc_net;
199
200 #if IS_ENABLED(CONFIG_IPV6)
201 struct in6_addr skc_v6_daddr;
202 struct in6_addr skc_v6_rcv_saddr;
203 #endif
204
205 atomic64_t skc_cookie;
206
207 /* following fields are padding to force
208 * offset(struct sock, sk_refcnt) == 128 on 64bit arches
209 * assuming IPV6 is enabled. We use this padding differently
210 * for different kind of 'sockets'
211 */
212 union {
213 unsigned long skc_flags;
214 struct sock *skc_listener; /* request_sock */
215 struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */
216 };
217 /*
218 * fields between dontcopy_begin/dontcopy_end
219 * are not copied in sock_copy()
220 */
221 /* private: */
222 int skc_dontcopy_begin[0];
223 /* public: */
224 union {
225 struct hlist_node skc_node;
226 struct hlist_nulls_node skc_nulls_node;
227 };
228 unsigned short skc_tx_queue_mapping;
229 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
230 unsigned short skc_rx_queue_mapping;
231 #endif
232 union {
233 int skc_incoming_cpu;
234 u32 skc_rcv_wnd;
235 u32 skc_tw_rcv_nxt; /* struct tcp_timewait_sock */
236 };
237
238 refcount_t skc_refcnt;
239 /* private: */
240 int skc_dontcopy_end[0];
241 union {
242 u32 skc_rxhash;
243 u32 skc_window_clamp;
244 u32 skc_tw_snd_nxt; /* struct tcp_timewait_sock */
245 };
246 /* public: */
247 };
248
249 struct bpf_local_storage;
250
251 /**
252 * struct sock - network layer representation of sockets
253 * @__sk_common: shared layout with inet_timewait_sock
254 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
255 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
256 * @sk_lock: synchronizer
257 * @sk_kern_sock: True if sock is using kernel lock classes
258 * @sk_rcvbuf: size of receive buffer in bytes
259 * @sk_wq: sock wait queue and async head
260 * @sk_rx_dst: receive input route used by early demux
261 * @sk_dst_cache: destination cache
262 * @sk_dst_pending_confirm: need to confirm neighbour
263 * @sk_policy: flow policy
264 * @sk_rx_skb_cache: cache copy of recently accessed RX skb
265 * @sk_receive_queue: incoming packets
266 * @sk_wmem_alloc: transmit queue bytes committed
267 * @sk_tsq_flags: TCP Small Queues flags
268 * @sk_write_queue: Packet sending queue
269 * @sk_omem_alloc: "o" is "option" or "other"
270 * @sk_wmem_queued: persistent queue size
271 * @sk_forward_alloc: space allocated forward
272 * @sk_napi_id: id of the last napi context to receive data for sk
273 * @sk_ll_usec: usecs to busypoll when there is no data
274 * @sk_allocation: allocation mode
275 * @sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler)
276 * @sk_pacing_status: Pacing status (requested, handled by sch_fq)
277 * @sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE)
278 * @sk_sndbuf: size of send buffer in bytes
279 * @__sk_flags_offset: empty field used to determine location of bitfield
280 * @sk_padding: unused element for alignment
281 * @sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets
282 * @sk_no_check_rx: allow zero checksum in RX packets
283 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
284 * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK)
285 * @sk_route_forced_caps: static, forced route capabilities
286 * (set in tcp_init_sock())
287 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
288 * @sk_gso_max_size: Maximum GSO segment size to build
289 * @sk_gso_max_segs: Maximum number of GSO segments
290 * @sk_pacing_shift: scaling factor for TCP Small Queues
291 * @sk_lingertime: %SO_LINGER l_linger setting
292 * @sk_backlog: always used with the per-socket spinlock held
293 * @sk_callback_lock: used with the callbacks in the end of this struct
294 * @sk_error_queue: rarely used
295 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
296 * IPV6_ADDRFORM for instance)
297 * @sk_err: last error
298 * @sk_err_soft: errors that don't cause failure but are the cause of a
299 * persistent failure not just 'timed out'
300 * @sk_drops: raw/udp drops counter
301 * @sk_ack_backlog: current listen backlog
302 * @sk_max_ack_backlog: listen backlog set in listen()
303 * @sk_uid: user id of owner
304 * @sk_prefer_busy_poll: prefer busypolling over softirq processing
305 * @sk_busy_poll_budget: napi processing budget when busypolling
306 * @sk_priority: %SO_PRIORITY setting
307 * @sk_type: socket type (%SOCK_STREAM, etc)
308 * @sk_protocol: which protocol this socket belongs in this network family
309 * @sk_peer_pid: &struct pid for this socket's peer
310 * @sk_peer_cred: %SO_PEERCRED setting
311 * @sk_rcvlowat: %SO_RCVLOWAT setting
312 * @sk_rcvtimeo: %SO_RCVTIMEO setting
313 * @sk_sndtimeo: %SO_SNDTIMEO setting
314 * @sk_txhash: computed flow hash for use on transmit
315 * @sk_filter: socket filtering instructions
316 * @sk_timer: sock cleanup timer
317 * @sk_stamp: time stamp of last packet received
318 * @sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only
319 * @sk_tsflags: SO_TIMESTAMPING socket options
320 * @sk_tskey: counter to disambiguate concurrent tstamp requests
321 * @sk_zckey: counter to order MSG_ZEROCOPY notifications
322 * @sk_socket: Identd and reporting IO signals
323 * @sk_user_data: RPC layer private data
324 * @sk_frag: cached page frag
325 * @sk_peek_off: current peek_offset value
326 * @sk_send_head: front of stuff to transmit
327 * @tcp_rtx_queue: TCP re-transmit queue [union with @sk_send_head]
328 * @sk_tx_skb_cache: cache copy of recently accessed TX skb
329 * @sk_security: used by security modules
330 * @sk_mark: generic packet mark
331 * @sk_cgrp_data: cgroup data for this cgroup
332 * @sk_memcg: this socket's memory cgroup association
333 * @sk_write_pending: a write to stream socket waits to start
334 * @sk_state_change: callback to indicate change in the state of the sock
335 * @sk_data_ready: callback to indicate there is data to be processed
336 * @sk_write_space: callback to indicate there is bf sending space available
337 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
338 * @sk_backlog_rcv: callback to process the backlog
339 * @sk_validate_xmit_skb: ptr to an optional validate function
340 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
341 * @sk_reuseport_cb: reuseport group container
342 * @sk_bpf_storage: ptr to cache and control for bpf_sk_storage
343 * @sk_rcu: used during RCU grace period
344 * @sk_clockid: clockid used by time-based scheduling (SO_TXTIME)
345 * @sk_txtime_deadline_mode: set deadline mode for SO_TXTIME
346 * @sk_txtime_report_errors: set report errors mode for SO_TXTIME
347 * @sk_txtime_unused: unused txtime flags
348 */
349 struct sock {
350 /*
351 * Now struct inet_timewait_sock also uses sock_common, so please just
352 * don't add nothing before this first member (__sk_common) --acme
353 */
354 struct sock_common __sk_common;
355 #define sk_node __sk_common.skc_node
356 #define sk_nulls_node __sk_common.skc_nulls_node
357 #define sk_refcnt __sk_common.skc_refcnt
358 #define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping
359 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
360 #define sk_rx_queue_mapping __sk_common.skc_rx_queue_mapping
361 #endif
362
363 #define sk_dontcopy_begin __sk_common.skc_dontcopy_begin
364 #define sk_dontcopy_end __sk_common.skc_dontcopy_end
365 #define sk_hash __sk_common.skc_hash
366 #define sk_portpair __sk_common.skc_portpair
367 #define sk_num __sk_common.skc_num
368 #define sk_dport __sk_common.skc_dport
369 #define sk_addrpair __sk_common.skc_addrpair
370 #define sk_daddr __sk_common.skc_daddr
371 #define sk_rcv_saddr __sk_common.skc_rcv_saddr
372 #define sk_family __sk_common.skc_family
373 #define sk_state __sk_common.skc_state
374 #define sk_reuse __sk_common.skc_reuse
375 #define sk_reuseport __sk_common.skc_reuseport
376 #define sk_ipv6only __sk_common.skc_ipv6only
377 #define sk_net_refcnt __sk_common.skc_net_refcnt
378 #define sk_bound_dev_if __sk_common.skc_bound_dev_if
379 #define sk_bind_node __sk_common.skc_bind_node
380 #define sk_prot __sk_common.skc_prot
381 #define sk_net __sk_common.skc_net
382 #define sk_v6_daddr __sk_common.skc_v6_daddr
383 #define sk_v6_rcv_saddr __sk_common.skc_v6_rcv_saddr
384 #define sk_cookie __sk_common.skc_cookie
385 #define sk_incoming_cpu __sk_common.skc_incoming_cpu
386 #define sk_flags __sk_common.skc_flags
387 #define sk_rxhash __sk_common.skc_rxhash
388
389 socket_lock_t sk_lock;
390 atomic_t sk_drops;
391 int sk_rcvlowat;
392 struct sk_buff_head sk_error_queue;
393 struct sk_buff *sk_rx_skb_cache;
394 struct sk_buff_head sk_receive_queue;
395 /*
396 * The backlog queue is special, it is always used with
397 * the per-socket spinlock held and requires low latency
398 * access. Therefore we special case it's implementation.
399 * Note : rmem_alloc is in this structure to fill a hole
400 * on 64bit arches, not because its logically part of
401 * backlog.
402 */
403 struct {
404 atomic_t rmem_alloc;
405 int len;
406 struct sk_buff *head;
407 struct sk_buff *tail;
408 } sk_backlog;
409 #define sk_rmem_alloc sk_backlog.rmem_alloc
410
411 int sk_forward_alloc;
412 #ifdef CONFIG_NET_RX_BUSY_POLL
413 unsigned int sk_ll_usec;
414 /* ===== mostly read cache line ===== */
415 unsigned int sk_napi_id;
416 #endif
417 int sk_rcvbuf;
418
419 struct sk_filter __rcu *sk_filter;
420 union {
421 struct socket_wq __rcu *sk_wq;
422 /* private: */
423 struct socket_wq *sk_wq_raw;
424 /* public: */
425 };
426 #ifdef CONFIG_XFRM
427 struct xfrm_policy __rcu *sk_policy[2];
428 #endif
429 struct dst_entry *sk_rx_dst;
430 struct dst_entry __rcu *sk_dst_cache;
431 atomic_t sk_omem_alloc;
432 int sk_sndbuf;
433
434 /* ===== cache line for TX ===== */
435 int sk_wmem_queued;
436 refcount_t sk_wmem_alloc;
437 unsigned long sk_tsq_flags;
438 union {
439 struct sk_buff *sk_send_head;
440 struct rb_root tcp_rtx_queue;
441 };
442 struct sk_buff *sk_tx_skb_cache;
443 struct sk_buff_head sk_write_queue;
444 __s32 sk_peek_off;
445 int sk_write_pending;
446 __u32 sk_dst_pending_confirm;
447 u32 sk_pacing_status; /* see enum sk_pacing */
448 long sk_sndtimeo;
449 struct timer_list sk_timer;
450 __u32 sk_priority;
451 __u32 sk_mark;
452 unsigned long sk_pacing_rate; /* bytes per second */
453 unsigned long sk_max_pacing_rate;
454 struct page_frag sk_frag;
455 netdev_features_t sk_route_caps;
456 netdev_features_t sk_route_nocaps;
457 netdev_features_t sk_route_forced_caps;
458 int sk_gso_type;
459 unsigned int sk_gso_max_size;
460 gfp_t sk_allocation;
461 __u32 sk_txhash;
462
463 /*
464 * Because of non atomicity rules, all
465 * changes are protected by socket lock.
466 */
467 u8 sk_padding : 1,
468 sk_kern_sock : 1,
469 sk_no_check_tx : 1,
470 sk_no_check_rx : 1,
471 sk_userlocks : 4;
472 u8 sk_pacing_shift;
473 u16 sk_type;
474 u16 sk_protocol;
475 u16 sk_gso_max_segs;
476 unsigned long sk_lingertime;
477 struct proto *sk_prot_creator;
478 rwlock_t sk_callback_lock;
479 int sk_err,
480 sk_err_soft;
481 u32 sk_ack_backlog;
482 u32 sk_max_ack_backlog;
483 kuid_t sk_uid;
484 #ifdef CONFIG_NET_RX_BUSY_POLL
485 u8 sk_prefer_busy_poll;
486 u16 sk_busy_poll_budget;
487 #endif
488 struct pid *sk_peer_pid;
489 const struct cred *sk_peer_cred;
490 long sk_rcvtimeo;
491 ktime_t sk_stamp;
492 #if BITS_PER_LONG==32
493 seqlock_t sk_stamp_seq;
494 #endif
495 u16 sk_tsflags;
496 u8 sk_shutdown;
497 u32 sk_tskey;
498 atomic_t sk_zckey;
499
500 u8 sk_clockid;
501 u8 sk_txtime_deadline_mode : 1,
502 sk_txtime_report_errors : 1,
503 sk_txtime_unused : 6;
504
505 struct socket *sk_socket;
506 void *sk_user_data;
507 #ifdef CONFIG_SECURITY
508 void *sk_security;
509 #endif
510 struct sock_cgroup_data sk_cgrp_data;
511 struct mem_cgroup *sk_memcg;
512 void (*sk_state_change)(struct sock *sk);
513 void (*sk_data_ready)(struct sock *sk);
514 void (*sk_write_space)(struct sock *sk);
515 void (*sk_error_report)(struct sock *sk);
516 int (*sk_backlog_rcv)(struct sock *sk,
517 struct sk_buff *skb);
518 #ifdef CONFIG_SOCK_VALIDATE_XMIT
519 struct sk_buff* (*sk_validate_xmit_skb)(struct sock *sk,
520 struct net_device *dev,
521 struct sk_buff *skb);
522 #endif
523 void (*sk_destruct)(struct sock *sk);
524 struct sock_reuseport __rcu *sk_reuseport_cb;
525 #ifdef CONFIG_BPF_SYSCALL
526 struct bpf_local_storage __rcu *sk_bpf_storage;
527 #endif
528 struct rcu_head sk_rcu;
529 };
530
531 enum sk_pacing {
532 SK_PACING_NONE = 0,
533 SK_PACING_NEEDED = 1,
534 SK_PACING_FQ = 2,
535 };
536
537 /* Pointer stored in sk_user_data might not be suitable for copying
538 * when cloning the socket. For instance, it can point to a reference
539 * counted object. sk_user_data bottom bit is set if pointer must not
540 * be copied.
541 */
542 #define SK_USER_DATA_NOCOPY 1UL
543 #define SK_USER_DATA_BPF 2UL /* Managed by BPF */
544 #define SK_USER_DATA_PTRMASK ~(SK_USER_DATA_NOCOPY | SK_USER_DATA_BPF)
545
546 /**
547 * sk_user_data_is_nocopy - Test if sk_user_data pointer must not be copied
548 * @sk: socket
549 */
sk_user_data_is_nocopy(const struct sock * sk)550 static inline bool sk_user_data_is_nocopy(const struct sock *sk)
551 {
552 return ((uintptr_t)sk->sk_user_data & SK_USER_DATA_NOCOPY);
553 }
554
555 #define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
556
557 #define rcu_dereference_sk_user_data(sk) \
558 ({ \
559 void *__tmp = rcu_dereference(__sk_user_data((sk))); \
560 (void *)((uintptr_t)__tmp & SK_USER_DATA_PTRMASK); \
561 })
562 #define rcu_assign_sk_user_data(sk, ptr) \
563 ({ \
564 uintptr_t __tmp = (uintptr_t)(ptr); \
565 WARN_ON_ONCE(__tmp & ~SK_USER_DATA_PTRMASK); \
566 rcu_assign_pointer(__sk_user_data((sk)), __tmp); \
567 })
568 #define rcu_assign_sk_user_data_nocopy(sk, ptr) \
569 ({ \
570 uintptr_t __tmp = (uintptr_t)(ptr); \
571 WARN_ON_ONCE(__tmp & ~SK_USER_DATA_PTRMASK); \
572 rcu_assign_pointer(__sk_user_data((sk)), \
573 __tmp | SK_USER_DATA_NOCOPY); \
574 })
575
576 /*
577 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
578 * or not whether his port will be reused by someone else. SK_FORCE_REUSE
579 * on a socket means that the socket will reuse everybody else's port
580 * without looking at the other's sk_reuse value.
581 */
582
583 #define SK_NO_REUSE 0
584 #define SK_CAN_REUSE 1
585 #define SK_FORCE_REUSE 2
586
587 int sk_set_peek_off(struct sock *sk, int val);
588
sk_peek_offset(struct sock * sk,int flags)589 static inline int sk_peek_offset(struct sock *sk, int flags)
590 {
591 if (unlikely(flags & MSG_PEEK)) {
592 return READ_ONCE(sk->sk_peek_off);
593 }
594
595 return 0;
596 }
597
sk_peek_offset_bwd(struct sock * sk,int val)598 static inline void sk_peek_offset_bwd(struct sock *sk, int val)
599 {
600 s32 off = READ_ONCE(sk->sk_peek_off);
601
602 if (unlikely(off >= 0)) {
603 off = max_t(s32, off - val, 0);
604 WRITE_ONCE(sk->sk_peek_off, off);
605 }
606 }
607
sk_peek_offset_fwd(struct sock * sk,int val)608 static inline void sk_peek_offset_fwd(struct sock *sk, int val)
609 {
610 sk_peek_offset_bwd(sk, -val);
611 }
612
613 /*
614 * Hashed lists helper routines
615 */
sk_entry(const struct hlist_node * node)616 static inline struct sock *sk_entry(const struct hlist_node *node)
617 {
618 return hlist_entry(node, struct sock, sk_node);
619 }
620
__sk_head(const struct hlist_head * head)621 static inline struct sock *__sk_head(const struct hlist_head *head)
622 {
623 return hlist_entry(head->first, struct sock, sk_node);
624 }
625
sk_head(const struct hlist_head * head)626 static inline struct sock *sk_head(const struct hlist_head *head)
627 {
628 return hlist_empty(head) ? NULL : __sk_head(head);
629 }
630
__sk_nulls_head(const struct hlist_nulls_head * head)631 static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
632 {
633 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
634 }
635
sk_nulls_head(const struct hlist_nulls_head * head)636 static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
637 {
638 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
639 }
640
sk_next(const struct sock * sk)641 static inline struct sock *sk_next(const struct sock *sk)
642 {
643 return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node);
644 }
645
sk_nulls_next(const struct sock * sk)646 static inline struct sock *sk_nulls_next(const struct sock *sk)
647 {
648 return (!is_a_nulls(sk->sk_nulls_node.next)) ?
649 hlist_nulls_entry(sk->sk_nulls_node.next,
650 struct sock, sk_nulls_node) :
651 NULL;
652 }
653
sk_unhashed(const struct sock * sk)654 static inline bool sk_unhashed(const struct sock *sk)
655 {
656 return hlist_unhashed(&sk->sk_node);
657 }
658
sk_hashed(const struct sock * sk)659 static inline bool sk_hashed(const struct sock *sk)
660 {
661 return !sk_unhashed(sk);
662 }
663
sk_node_init(struct hlist_node * node)664 static inline void sk_node_init(struct hlist_node *node)
665 {
666 node->pprev = NULL;
667 }
668
sk_nulls_node_init(struct hlist_nulls_node * node)669 static inline void sk_nulls_node_init(struct hlist_nulls_node *node)
670 {
671 node->pprev = NULL;
672 }
673
__sk_del_node(struct sock * sk)674 static inline void __sk_del_node(struct sock *sk)
675 {
676 __hlist_del(&sk->sk_node);
677 }
678
679 /* NB: equivalent to hlist_del_init_rcu */
__sk_del_node_init(struct sock * sk)680 static inline bool __sk_del_node_init(struct sock *sk)
681 {
682 if (sk_hashed(sk)) {
683 __sk_del_node(sk);
684 sk_node_init(&sk->sk_node);
685 return true;
686 }
687 return false;
688 }
689
690 /* Grab socket reference count. This operation is valid only
691 when sk is ALREADY grabbed f.e. it is found in hash table
692 or a list and the lookup is made under lock preventing hash table
693 modifications.
694 */
695
sock_hold(struct sock * sk)696 static __always_inline void sock_hold(struct sock *sk)
697 {
698 refcount_inc(&sk->sk_refcnt);
699 }
700
701 /* Ungrab socket in the context, which assumes that socket refcnt
702 cannot hit zero, f.e. it is true in context of any socketcall.
703 */
__sock_put(struct sock * sk)704 static __always_inline void __sock_put(struct sock *sk)
705 {
706 refcount_dec(&sk->sk_refcnt);
707 }
708
sk_del_node_init(struct sock * sk)709 static inline bool sk_del_node_init(struct sock *sk)
710 {
711 bool rc = __sk_del_node_init(sk);
712
713 if (rc) {
714 /* paranoid for a while -acme */
715 WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
716 __sock_put(sk);
717 }
718 return rc;
719 }
720 #define sk_del_node_init_rcu(sk) sk_del_node_init(sk)
721
__sk_nulls_del_node_init_rcu(struct sock * sk)722 static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
723 {
724 if (sk_hashed(sk)) {
725 hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
726 return true;
727 }
728 return false;
729 }
730
sk_nulls_del_node_init_rcu(struct sock * sk)731 static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
732 {
733 bool rc = __sk_nulls_del_node_init_rcu(sk);
734
735 if (rc) {
736 /* paranoid for a while -acme */
737 WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
738 __sock_put(sk);
739 }
740 return rc;
741 }
742
__sk_add_node(struct sock * sk,struct hlist_head * list)743 static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
744 {
745 hlist_add_head(&sk->sk_node, list);
746 }
747
sk_add_node(struct sock * sk,struct hlist_head * list)748 static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
749 {
750 sock_hold(sk);
751 __sk_add_node(sk, list);
752 }
753
sk_add_node_rcu(struct sock * sk,struct hlist_head * list)754 static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
755 {
756 sock_hold(sk);
757 if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
758 sk->sk_family == AF_INET6)
759 hlist_add_tail_rcu(&sk->sk_node, list);
760 else
761 hlist_add_head_rcu(&sk->sk_node, list);
762 }
763
sk_add_node_tail_rcu(struct sock * sk,struct hlist_head * list)764 static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list)
765 {
766 sock_hold(sk);
767 hlist_add_tail_rcu(&sk->sk_node, list);
768 }
769
__sk_nulls_add_node_rcu(struct sock * sk,struct hlist_nulls_head * list)770 static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
771 {
772 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
773 }
774
__sk_nulls_add_node_tail_rcu(struct sock * sk,struct hlist_nulls_head * list)775 static inline void __sk_nulls_add_node_tail_rcu(struct sock *sk, struct hlist_nulls_head *list)
776 {
777 hlist_nulls_add_tail_rcu(&sk->sk_nulls_node, list);
778 }
779
sk_nulls_add_node_rcu(struct sock * sk,struct hlist_nulls_head * list)780 static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
781 {
782 sock_hold(sk);
783 __sk_nulls_add_node_rcu(sk, list);
784 }
785
__sk_del_bind_node(struct sock * sk)786 static inline void __sk_del_bind_node(struct sock *sk)
787 {
788 __hlist_del(&sk->sk_bind_node);
789 }
790
sk_add_bind_node(struct sock * sk,struct hlist_head * list)791 static inline void sk_add_bind_node(struct sock *sk,
792 struct hlist_head *list)
793 {
794 hlist_add_head(&sk->sk_bind_node, list);
795 }
796
797 #define sk_for_each(__sk, list) \
798 hlist_for_each_entry(__sk, list, sk_node)
799 #define sk_for_each_rcu(__sk, list) \
800 hlist_for_each_entry_rcu(__sk, list, sk_node)
801 #define sk_nulls_for_each(__sk, node, list) \
802 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
803 #define sk_nulls_for_each_rcu(__sk, node, list) \
804 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
805 #define sk_for_each_from(__sk) \
806 hlist_for_each_entry_from(__sk, sk_node)
807 #define sk_nulls_for_each_from(__sk, node) \
808 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
809 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
810 #define sk_for_each_safe(__sk, tmp, list) \
811 hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
812 #define sk_for_each_bound(__sk, list) \
813 hlist_for_each_entry(__sk, list, sk_bind_node)
814
815 /**
816 * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset
817 * @tpos: the type * to use as a loop cursor.
818 * @pos: the &struct hlist_node to use as a loop cursor.
819 * @head: the head for your list.
820 * @offset: offset of hlist_node within the struct.
821 *
822 */
823 #define sk_for_each_entry_offset_rcu(tpos, pos, head, offset) \
824 for (pos = rcu_dereference(hlist_first_rcu(head)); \
825 pos != NULL && \
826 ({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \
827 pos = rcu_dereference(hlist_next_rcu(pos)))
828
sk_user_ns(struct sock * sk)829 static inline struct user_namespace *sk_user_ns(struct sock *sk)
830 {
831 /* Careful only use this in a context where these parameters
832 * can not change and must all be valid, such as recvmsg from
833 * userspace.
834 */
835 return sk->sk_socket->file->f_cred->user_ns;
836 }
837
838 /* Sock flags */
839 enum sock_flags {
840 SOCK_DEAD,
841 SOCK_DONE,
842 SOCK_URGINLINE,
843 SOCK_KEEPOPEN,
844 SOCK_LINGER,
845 SOCK_DESTROY,
846 SOCK_BROADCAST,
847 SOCK_TIMESTAMP,
848 SOCK_ZAPPED,
849 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
850 SOCK_DBG, /* %SO_DEBUG setting */
851 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
852 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
853 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
854 SOCK_MEMALLOC, /* VM depends on this socket for swapping */
855 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */
856 SOCK_FASYNC, /* fasync() active */
857 SOCK_RXQ_OVFL,
858 SOCK_ZEROCOPY, /* buffers from userspace */
859 SOCK_WIFI_STATUS, /* push wifi status to userspace */
860 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
861 * Will use last 4 bytes of packet sent from
862 * user-space instead.
863 */
864 SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
865 SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
866 SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */
867 SOCK_TXTIME,
868 SOCK_XDP, /* XDP is attached */
869 SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */
870 };
871
872 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
873
sock_copy_flags(struct sock * nsk,struct sock * osk)874 static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
875 {
876 nsk->sk_flags = osk->sk_flags;
877 }
878
sock_set_flag(struct sock * sk,enum sock_flags flag)879 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
880 {
881 __set_bit(flag, &sk->sk_flags);
882 }
883
sock_reset_flag(struct sock * sk,enum sock_flags flag)884 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
885 {
886 __clear_bit(flag, &sk->sk_flags);
887 }
888
sock_valbool_flag(struct sock * sk,enum sock_flags bit,int valbool)889 static inline void sock_valbool_flag(struct sock *sk, enum sock_flags bit,
890 int valbool)
891 {
892 if (valbool)
893 sock_set_flag(sk, bit);
894 else
895 sock_reset_flag(sk, bit);
896 }
897
sock_flag(const struct sock * sk,enum sock_flags flag)898 static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
899 {
900 return test_bit(flag, &sk->sk_flags);
901 }
902
903 #ifdef CONFIG_NET
904 DECLARE_STATIC_KEY_FALSE(memalloc_socks_key);
sk_memalloc_socks(void)905 static inline int sk_memalloc_socks(void)
906 {
907 return static_branch_unlikely(&memalloc_socks_key);
908 }
909
910 void __receive_sock(struct file *file);
911 #else
912
sk_memalloc_socks(void)913 static inline int sk_memalloc_socks(void)
914 {
915 return 0;
916 }
917
__receive_sock(struct file * file)918 static inline void __receive_sock(struct file *file)
919 { }
920 #endif
921
sk_gfp_mask(const struct sock * sk,gfp_t gfp_mask)922 static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask)
923 {
924 return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC);
925 }
926
sk_acceptq_removed(struct sock * sk)927 static inline void sk_acceptq_removed(struct sock *sk)
928 {
929 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1);
930 }
931
sk_acceptq_added(struct sock * sk)932 static inline void sk_acceptq_added(struct sock *sk)
933 {
934 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1);
935 }
936
937 /* Note: If you think the test should be:
938 * return READ_ONCE(sk->sk_ack_backlog) >= READ_ONCE(sk->sk_max_ack_backlog);
939 * Then please take a look at commit 64a146513f8f ("[NET]: Revert incorrect accept queue backlog changes.")
940 */
sk_acceptq_is_full(const struct sock * sk)941 static inline bool sk_acceptq_is_full(const struct sock *sk)
942 {
943 return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(sk->sk_max_ack_backlog);
944 }
945
946 /*
947 * Compute minimal free write space needed to queue new packets.
948 */
sk_stream_min_wspace(const struct sock * sk)949 static inline int sk_stream_min_wspace(const struct sock *sk)
950 {
951 return READ_ONCE(sk->sk_wmem_queued) >> 1;
952 }
953
sk_stream_wspace(const struct sock * sk)954 static inline int sk_stream_wspace(const struct sock *sk)
955 {
956 return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued);
957 }
958
sk_wmem_queued_add(struct sock * sk,int val)959 static inline void sk_wmem_queued_add(struct sock *sk, int val)
960 {
961 WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val);
962 }
963
964 void sk_stream_write_space(struct sock *sk);
965
966 /* OOB backlog add */
__sk_add_backlog(struct sock * sk,struct sk_buff * skb)967 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
968 {
969 /* dont let skb dst not refcounted, we are going to leave rcu lock */
970 skb_dst_force(skb);
971
972 if (!sk->sk_backlog.tail)
973 WRITE_ONCE(sk->sk_backlog.head, skb);
974 else
975 sk->sk_backlog.tail->next = skb;
976
977 WRITE_ONCE(sk->sk_backlog.tail, skb);
978 skb->next = NULL;
979 }
980
981 /*
982 * Take into account size of receive queue and backlog queue
983 * Do not take into account this skb truesize,
984 * to allow even a single big packet to come.
985 */
sk_rcvqueues_full(const struct sock * sk,unsigned int limit)986 static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
987 {
988 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
989
990 return qsize > limit;
991 }
992
993 /* The per-socket spinlock must be held here. */
sk_add_backlog(struct sock * sk,struct sk_buff * skb,unsigned int limit)994 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
995 unsigned int limit)
996 {
997 if (sk_rcvqueues_full(sk, limit))
998 return -ENOBUFS;
999
1000 /*
1001 * If the skb was allocated from pfmemalloc reserves, only
1002 * allow SOCK_MEMALLOC sockets to use it as this socket is
1003 * helping free memory
1004 */
1005 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC))
1006 return -ENOMEM;
1007
1008 __sk_add_backlog(sk, skb);
1009 sk->sk_backlog.len += skb->truesize;
1010 return 0;
1011 }
1012
1013 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
1014
sk_backlog_rcv(struct sock * sk,struct sk_buff * skb)1015 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
1016 {
1017 if (sk_memalloc_socks() && skb_pfmemalloc(skb))
1018 return __sk_backlog_rcv(sk, skb);
1019
1020 return sk->sk_backlog_rcv(sk, skb);
1021 }
1022
sk_incoming_cpu_update(struct sock * sk)1023 static inline void sk_incoming_cpu_update(struct sock *sk)
1024 {
1025 int cpu = raw_smp_processor_id();
1026
1027 if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu))
1028 WRITE_ONCE(sk->sk_incoming_cpu, cpu);
1029 }
1030
sock_rps_record_flow_hash(__u32 hash)1031 static inline void sock_rps_record_flow_hash(__u32 hash)
1032 {
1033 #ifdef CONFIG_RPS
1034 struct rps_sock_flow_table *sock_flow_table;
1035
1036 rcu_read_lock();
1037 sock_flow_table = rcu_dereference(rps_sock_flow_table);
1038 rps_record_sock_flow(sock_flow_table, hash);
1039 rcu_read_unlock();
1040 #endif
1041 }
1042
sock_rps_record_flow(const struct sock * sk)1043 static inline void sock_rps_record_flow(const struct sock *sk)
1044 {
1045 #ifdef CONFIG_RPS
1046 if (static_branch_unlikely(&rfs_needed)) {
1047 /* Reading sk->sk_rxhash might incur an expensive cache line
1048 * miss.
1049 *
1050 * TCP_ESTABLISHED does cover almost all states where RFS
1051 * might be useful, and is cheaper [1] than testing :
1052 * IPv4: inet_sk(sk)->inet_daddr
1053 * IPv6: ipv6_addr_any(&sk->sk_v6_daddr)
1054 * OR an additional socket flag
1055 * [1] : sk_state and sk_prot are in the same cache line.
1056 */
1057 if (sk->sk_state == TCP_ESTABLISHED)
1058 sock_rps_record_flow_hash(sk->sk_rxhash);
1059 }
1060 #endif
1061 }
1062
sock_rps_save_rxhash(struct sock * sk,const struct sk_buff * skb)1063 static inline void sock_rps_save_rxhash(struct sock *sk,
1064 const struct sk_buff *skb)
1065 {
1066 #ifdef CONFIG_RPS
1067 if (unlikely(sk->sk_rxhash != skb->hash))
1068 sk->sk_rxhash = skb->hash;
1069 #endif
1070 }
1071
sock_rps_reset_rxhash(struct sock * sk)1072 static inline void sock_rps_reset_rxhash(struct sock *sk)
1073 {
1074 #ifdef CONFIG_RPS
1075 sk->sk_rxhash = 0;
1076 #endif
1077 }
1078
1079 #define sk_wait_event(__sk, __timeo, __condition, __wait) \
1080 ({ int __rc; \
1081 release_sock(__sk); \
1082 __rc = __condition; \
1083 if (!__rc) { \
1084 *(__timeo) = wait_woken(__wait, \
1085 TASK_INTERRUPTIBLE, \
1086 *(__timeo)); \
1087 } \
1088 sched_annotate_sleep(); \
1089 lock_sock(__sk); \
1090 __rc = __condition; \
1091 __rc; \
1092 })
1093
1094 int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
1095 int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
1096 void sk_stream_wait_close(struct sock *sk, long timeo_p);
1097 int sk_stream_error(struct sock *sk, int flags, int err);
1098 void sk_stream_kill_queues(struct sock *sk);
1099 void sk_set_memalloc(struct sock *sk);
1100 void sk_clear_memalloc(struct sock *sk);
1101
1102 void __sk_flush_backlog(struct sock *sk);
1103
sk_flush_backlog(struct sock * sk)1104 static inline bool sk_flush_backlog(struct sock *sk)
1105 {
1106 if (unlikely(READ_ONCE(sk->sk_backlog.tail))) {
1107 __sk_flush_backlog(sk);
1108 return true;
1109 }
1110 return false;
1111 }
1112
1113 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb);
1114
1115 struct request_sock_ops;
1116 struct timewait_sock_ops;
1117 struct inet_hashinfo;
1118 struct raw_hashinfo;
1119 struct smc_hashinfo;
1120 struct module;
1121 struct sk_psock;
1122
1123 /*
1124 * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes
1125 * un-modified. Special care is taken when initializing object to zero.
1126 */
sk_prot_clear_nulls(struct sock * sk,int size)1127 static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1128 {
1129 if (offsetof(struct sock, sk_node.next) != 0)
1130 memset(sk, 0, offsetof(struct sock, sk_node.next));
1131 memset(&sk->sk_node.pprev, 0,
1132 size - offsetof(struct sock, sk_node.pprev));
1133 }
1134
1135 /* Networking protocol blocks we attach to sockets.
1136 * socket layer -> transport layer interface
1137 */
1138 struct proto {
1139 void (*close)(struct sock *sk,
1140 long timeout);
1141 int (*pre_connect)(struct sock *sk,
1142 struct sockaddr *uaddr,
1143 int addr_len);
1144 int (*connect)(struct sock *sk,
1145 struct sockaddr *uaddr,
1146 int addr_len);
1147 int (*disconnect)(struct sock *sk, int flags);
1148
1149 struct sock * (*accept)(struct sock *sk, int flags, int *err,
1150 bool kern);
1151
1152 int (*ioctl)(struct sock *sk, int cmd,
1153 unsigned long arg);
1154 int (*init)(struct sock *sk);
1155 void (*destroy)(struct sock *sk);
1156 void (*shutdown)(struct sock *sk, int how);
1157 int (*setsockopt)(struct sock *sk, int level,
1158 int optname, sockptr_t optval,
1159 unsigned int optlen);
1160 int (*getsockopt)(struct sock *sk, int level,
1161 int optname, char __user *optval,
1162 int __user *option);
1163 void (*keepalive)(struct sock *sk, int valbool);
1164 #ifdef CONFIG_COMPAT
1165 int (*compat_ioctl)(struct sock *sk,
1166 unsigned int cmd, unsigned long arg);
1167 #endif
1168 int (*sendmsg)(struct sock *sk, struct msghdr *msg,
1169 size_t len);
1170 int (*recvmsg)(struct sock *sk, struct msghdr *msg,
1171 size_t len, int noblock, int flags,
1172 int *addr_len);
1173 int (*sendpage)(struct sock *sk, struct page *page,
1174 int offset, size_t size, int flags);
1175 int (*bind)(struct sock *sk,
1176 struct sockaddr *addr, int addr_len);
1177 int (*bind_add)(struct sock *sk,
1178 struct sockaddr *addr, int addr_len);
1179
1180 int (*backlog_rcv) (struct sock *sk,
1181 struct sk_buff *skb);
1182 bool (*bpf_bypass_getsockopt)(int level,
1183 int optname);
1184
1185 void (*release_cb)(struct sock *sk);
1186
1187 /* Keeping track of sk's, looking them up, and port selection methods. */
1188 int (*hash)(struct sock *sk);
1189 void (*unhash)(struct sock *sk);
1190 void (*rehash)(struct sock *sk);
1191 int (*get_port)(struct sock *sk, unsigned short snum);
1192 #ifdef CONFIG_BPF_SYSCALL
1193 int (*psock_update_sk_prot)(struct sock *sk,
1194 struct sk_psock *psock,
1195 bool restore);
1196 #endif
1197
1198 /* Keeping track of sockets in use */
1199 #ifdef CONFIG_PROC_FS
1200 unsigned int inuse_idx;
1201 #endif
1202
1203 bool (*stream_memory_free)(const struct sock *sk, int wake);
1204 bool (*stream_memory_read)(const struct sock *sk);
1205 /* Memory pressure */
1206 void (*enter_memory_pressure)(struct sock *sk);
1207 void (*leave_memory_pressure)(struct sock *sk);
1208 atomic_long_t *memory_allocated; /* Current allocated memory. */
1209 struct percpu_counter *sockets_allocated; /* Current number of sockets. */
1210 /*
1211 * Pressure flag: try to collapse.
1212 * Technical note: it is used by multiple contexts non atomically.
1213 * All the __sk_mem_schedule() is of this nature: accounting
1214 * is strict, actions are advisory and have some latency.
1215 */
1216 unsigned long *memory_pressure;
1217 long *sysctl_mem;
1218
1219 int *sysctl_wmem;
1220 int *sysctl_rmem;
1221 u32 sysctl_wmem_offset;
1222 u32 sysctl_rmem_offset;
1223
1224 int max_header;
1225 bool no_autobind;
1226
1227 struct kmem_cache *slab;
1228 unsigned int obj_size;
1229 slab_flags_t slab_flags;
1230 unsigned int useroffset; /* Usercopy region offset */
1231 unsigned int usersize; /* Usercopy region size */
1232
1233 struct percpu_counter *orphan_count;
1234
1235 struct request_sock_ops *rsk_prot;
1236 struct timewait_sock_ops *twsk_prot;
1237
1238 union {
1239 struct inet_hashinfo *hashinfo;
1240 struct udp_table *udp_table;
1241 struct raw_hashinfo *raw_hash;
1242 struct smc_hashinfo *smc_hash;
1243 } h;
1244
1245 struct module *owner;
1246
1247 char name[32];
1248
1249 struct list_head node;
1250 #ifdef SOCK_REFCNT_DEBUG
1251 atomic_t socks;
1252 #endif
1253 int (*diag_destroy)(struct sock *sk, int err);
1254 } __randomize_layout;
1255
1256 int proto_register(struct proto *prot, int alloc_slab);
1257 void proto_unregister(struct proto *prot);
1258 int sock_load_diag_module(int family, int protocol);
1259
1260 #ifdef SOCK_REFCNT_DEBUG
sk_refcnt_debug_inc(struct sock * sk)1261 static inline void sk_refcnt_debug_inc(struct sock *sk)
1262 {
1263 atomic_inc(&sk->sk_prot->socks);
1264 }
1265
sk_refcnt_debug_dec(struct sock * sk)1266 static inline void sk_refcnt_debug_dec(struct sock *sk)
1267 {
1268 atomic_dec(&sk->sk_prot->socks);
1269 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
1270 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
1271 }
1272
sk_refcnt_debug_release(const struct sock * sk)1273 static inline void sk_refcnt_debug_release(const struct sock *sk)
1274 {
1275 if (refcount_read(&sk->sk_refcnt) != 1)
1276 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
1277 sk->sk_prot->name, sk, refcount_read(&sk->sk_refcnt));
1278 }
1279 #else /* SOCK_REFCNT_DEBUG */
1280 #define sk_refcnt_debug_inc(sk) do { } while (0)
1281 #define sk_refcnt_debug_dec(sk) do { } while (0)
1282 #define sk_refcnt_debug_release(sk) do { } while (0)
1283 #endif /* SOCK_REFCNT_DEBUG */
1284
1285 INDIRECT_CALLABLE_DECLARE(bool tcp_stream_memory_free(const struct sock *sk, int wake));
1286
__sk_stream_memory_free(const struct sock * sk,int wake)1287 static inline bool __sk_stream_memory_free(const struct sock *sk, int wake)
1288 {
1289 if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf))
1290 return false;
1291
1292 #ifdef CONFIG_INET
1293 return sk->sk_prot->stream_memory_free ?
1294 INDIRECT_CALL_1(sk->sk_prot->stream_memory_free,
1295 tcp_stream_memory_free,
1296 sk, wake) : true;
1297 #else
1298 return sk->sk_prot->stream_memory_free ?
1299 sk->sk_prot->stream_memory_free(sk, wake) : true;
1300 #endif
1301 }
1302
sk_stream_memory_free(const struct sock * sk)1303 static inline bool sk_stream_memory_free(const struct sock *sk)
1304 {
1305 return __sk_stream_memory_free(sk, 0);
1306 }
1307
__sk_stream_is_writeable(const struct sock * sk,int wake)1308 static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake)
1309 {
1310 return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
1311 __sk_stream_memory_free(sk, wake);
1312 }
1313
sk_stream_is_writeable(const struct sock * sk)1314 static inline bool sk_stream_is_writeable(const struct sock *sk)
1315 {
1316 return __sk_stream_is_writeable(sk, 0);
1317 }
1318
sk_under_cgroup_hierarchy(struct sock * sk,struct cgroup * ancestor)1319 static inline int sk_under_cgroup_hierarchy(struct sock *sk,
1320 struct cgroup *ancestor)
1321 {
1322 #ifdef CONFIG_SOCK_CGROUP_DATA
1323 return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data),
1324 ancestor);
1325 #else
1326 return -ENOTSUPP;
1327 #endif
1328 }
1329
sk_has_memory_pressure(const struct sock * sk)1330 static inline bool sk_has_memory_pressure(const struct sock *sk)
1331 {
1332 return sk->sk_prot->memory_pressure != NULL;
1333 }
1334
sk_under_memory_pressure(const struct sock * sk)1335 static inline bool sk_under_memory_pressure(const struct sock *sk)
1336 {
1337 if (!sk->sk_prot->memory_pressure)
1338 return false;
1339
1340 if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
1341 mem_cgroup_under_socket_pressure(sk->sk_memcg))
1342 return true;
1343
1344 return !!*sk->sk_prot->memory_pressure;
1345 }
1346
1347 static inline long
sk_memory_allocated(const struct sock * sk)1348 sk_memory_allocated(const struct sock *sk)
1349 {
1350 return atomic_long_read(sk->sk_prot->memory_allocated);
1351 }
1352
1353 static inline long
sk_memory_allocated_add(struct sock * sk,int amt)1354 sk_memory_allocated_add(struct sock *sk, int amt)
1355 {
1356 return atomic_long_add_return(amt, sk->sk_prot->memory_allocated);
1357 }
1358
1359 static inline void
sk_memory_allocated_sub(struct sock * sk,int amt)1360 sk_memory_allocated_sub(struct sock *sk, int amt)
1361 {
1362 atomic_long_sub(amt, sk->sk_prot->memory_allocated);
1363 }
1364
1365 #define SK_ALLOC_PERCPU_COUNTER_BATCH 16
1366
sk_sockets_allocated_dec(struct sock * sk)1367 static inline void sk_sockets_allocated_dec(struct sock *sk)
1368 {
1369 percpu_counter_add_batch(sk->sk_prot->sockets_allocated, -1,
1370 SK_ALLOC_PERCPU_COUNTER_BATCH);
1371 }
1372
sk_sockets_allocated_inc(struct sock * sk)1373 static inline void sk_sockets_allocated_inc(struct sock *sk)
1374 {
1375 percpu_counter_add_batch(sk->sk_prot->sockets_allocated, 1,
1376 SK_ALLOC_PERCPU_COUNTER_BATCH);
1377 }
1378
1379 static inline u64
sk_sockets_allocated_read_positive(struct sock * sk)1380 sk_sockets_allocated_read_positive(struct sock *sk)
1381 {
1382 return percpu_counter_read_positive(sk->sk_prot->sockets_allocated);
1383 }
1384
1385 static inline int
proto_sockets_allocated_sum_positive(struct proto * prot)1386 proto_sockets_allocated_sum_positive(struct proto *prot)
1387 {
1388 return percpu_counter_sum_positive(prot->sockets_allocated);
1389 }
1390
1391 static inline long
proto_memory_allocated(struct proto * prot)1392 proto_memory_allocated(struct proto *prot)
1393 {
1394 return atomic_long_read(prot->memory_allocated);
1395 }
1396
1397 static inline bool
proto_memory_pressure(struct proto * prot)1398 proto_memory_pressure(struct proto *prot)
1399 {
1400 if (!prot->memory_pressure)
1401 return false;
1402 return !!*prot->memory_pressure;
1403 }
1404
1405
1406 #ifdef CONFIG_PROC_FS
1407 /* Called with local bh disabled */
1408 void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
1409 int sock_prot_inuse_get(struct net *net, struct proto *proto);
1410 int sock_inuse_get(struct net *net);
1411 #else
sock_prot_inuse_add(struct net * net,struct proto * prot,int inc)1412 static inline void sock_prot_inuse_add(struct net *net, struct proto *prot,
1413 int inc)
1414 {
1415 }
1416 #endif
1417
1418
1419 /* With per-bucket locks this operation is not-atomic, so that
1420 * this version is not worse.
1421 */
__sk_prot_rehash(struct sock * sk)1422 static inline int __sk_prot_rehash(struct sock *sk)
1423 {
1424 sk->sk_prot->unhash(sk);
1425 return sk->sk_prot->hash(sk);
1426 }
1427
1428 /* About 10 seconds */
1429 #define SOCK_DESTROY_TIME (10*HZ)
1430
1431 /* Sockets 0-1023 can't be bound to unless you are superuser */
1432 #define PROT_SOCK 1024
1433
1434 #define SHUTDOWN_MASK 3
1435 #define RCV_SHUTDOWN 1
1436 #define SEND_SHUTDOWN 2
1437
1438 #define SOCK_SNDBUF_LOCK 1
1439 #define SOCK_RCVBUF_LOCK 2
1440 #define SOCK_BINDADDR_LOCK 4
1441 #define SOCK_BINDPORT_LOCK 8
1442
1443 struct socket_alloc {
1444 struct socket socket;
1445 struct inode vfs_inode;
1446 };
1447
SOCKET_I(struct inode * inode)1448 static inline struct socket *SOCKET_I(struct inode *inode)
1449 {
1450 return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1451 }
1452
SOCK_INODE(struct socket * socket)1453 static inline struct inode *SOCK_INODE(struct socket *socket)
1454 {
1455 return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1456 }
1457
1458 /*
1459 * Functions for memory accounting
1460 */
1461 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind);
1462 int __sk_mem_schedule(struct sock *sk, int size, int kind);
1463 void __sk_mem_reduce_allocated(struct sock *sk, int amount);
1464 void __sk_mem_reclaim(struct sock *sk, int amount);
1465
1466 /* We used to have PAGE_SIZE here, but systems with 64KB pages
1467 * do not necessarily have 16x time more memory than 4KB ones.
1468 */
1469 #define SK_MEM_QUANTUM 4096
1470 #define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
1471 #define SK_MEM_SEND 0
1472 #define SK_MEM_RECV 1
1473
1474 /* sysctl_mem values are in pages, we convert them in SK_MEM_QUANTUM units */
sk_prot_mem_limits(const struct sock * sk,int index)1475 static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1476 {
1477 long val = sk->sk_prot->sysctl_mem[index];
1478
1479 #if PAGE_SIZE > SK_MEM_QUANTUM
1480 val <<= PAGE_SHIFT - SK_MEM_QUANTUM_SHIFT;
1481 #elif PAGE_SIZE < SK_MEM_QUANTUM
1482 val >>= SK_MEM_QUANTUM_SHIFT - PAGE_SHIFT;
1483 #endif
1484 return val;
1485 }
1486
sk_mem_pages(int amt)1487 static inline int sk_mem_pages(int amt)
1488 {
1489 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
1490 }
1491
sk_has_account(struct sock * sk)1492 static inline bool sk_has_account(struct sock *sk)
1493 {
1494 /* return true if protocol supports memory accounting */
1495 return !!sk->sk_prot->memory_allocated;
1496 }
1497
sk_wmem_schedule(struct sock * sk,int size)1498 static inline bool sk_wmem_schedule(struct sock *sk, int size)
1499 {
1500 if (!sk_has_account(sk))
1501 return true;
1502 return size <= sk->sk_forward_alloc ||
1503 __sk_mem_schedule(sk, size, SK_MEM_SEND);
1504 }
1505
1506 static inline bool
sk_rmem_schedule(struct sock * sk,struct sk_buff * skb,int size)1507 sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
1508 {
1509 if (!sk_has_account(sk))
1510 return true;
1511 return size <= sk->sk_forward_alloc ||
1512 __sk_mem_schedule(sk, size, SK_MEM_RECV) ||
1513 skb_pfmemalloc(skb);
1514 }
1515
sk_mem_reclaim(struct sock * sk)1516 static inline void sk_mem_reclaim(struct sock *sk)
1517 {
1518 if (!sk_has_account(sk))
1519 return;
1520 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
1521 __sk_mem_reclaim(sk, sk->sk_forward_alloc);
1522 }
1523
sk_mem_reclaim_partial(struct sock * sk)1524 static inline void sk_mem_reclaim_partial(struct sock *sk)
1525 {
1526 if (!sk_has_account(sk))
1527 return;
1528 if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
1529 __sk_mem_reclaim(sk, sk->sk_forward_alloc - 1);
1530 }
1531
sk_mem_charge(struct sock * sk,int size)1532 static inline void sk_mem_charge(struct sock *sk, int size)
1533 {
1534 if (!sk_has_account(sk))
1535 return;
1536 sk->sk_forward_alloc -= size;
1537 }
1538
sk_mem_uncharge(struct sock * sk,int size)1539 static inline void sk_mem_uncharge(struct sock *sk, int size)
1540 {
1541 if (!sk_has_account(sk))
1542 return;
1543 sk->sk_forward_alloc += size;
1544
1545 /* Avoid a possible overflow.
1546 * TCP send queues can make this happen, if sk_mem_reclaim()
1547 * is not called and more than 2 GBytes are released at once.
1548 *
1549 * If we reach 2 MBytes, reclaim 1 MBytes right now, there is
1550 * no need to hold that much forward allocation anyway.
1551 */
1552 if (unlikely(sk->sk_forward_alloc >= 1 << 21))
1553 __sk_mem_reclaim(sk, 1 << 20);
1554 }
1555
1556 DECLARE_STATIC_KEY_FALSE(tcp_tx_skb_cache_key);
sk_wmem_free_skb(struct sock * sk,struct sk_buff * skb)1557 static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
1558 {
1559 sk_wmem_queued_add(sk, -skb->truesize);
1560 sk_mem_uncharge(sk, skb->truesize);
1561 if (static_branch_unlikely(&tcp_tx_skb_cache_key) &&
1562 !sk->sk_tx_skb_cache && !skb_cloned(skb)) {
1563 skb_ext_reset(skb);
1564 skb_zcopy_clear(skb, true);
1565 sk->sk_tx_skb_cache = skb;
1566 return;
1567 }
1568 __kfree_skb(skb);
1569 }
1570
sock_release_ownership(struct sock * sk)1571 static inline void sock_release_ownership(struct sock *sk)
1572 {
1573 if (sk->sk_lock.owned) {
1574 sk->sk_lock.owned = 0;
1575
1576 /* The sk_lock has mutex_unlock() semantics: */
1577 mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1578 }
1579 }
1580
1581 /*
1582 * Macro so as to not evaluate some arguments when
1583 * lockdep is not enabled.
1584 *
1585 * Mark both the sk_lock and the sk_lock.slock as a
1586 * per-address-family lock class.
1587 */
1588 #define sock_lock_init_class_and_name(sk, sname, skey, name, key) \
1589 do { \
1590 sk->sk_lock.owned = 0; \
1591 init_waitqueue_head(&sk->sk_lock.wq); \
1592 spin_lock_init(&(sk)->sk_lock.slock); \
1593 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \
1594 sizeof((sk)->sk_lock)); \
1595 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \
1596 (skey), (sname)); \
1597 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \
1598 } while (0)
1599
lockdep_sock_is_held(const struct sock * sk)1600 static inline bool lockdep_sock_is_held(const struct sock *sk)
1601 {
1602 return lockdep_is_held(&sk->sk_lock) ||
1603 lockdep_is_held(&sk->sk_lock.slock);
1604 }
1605
1606 void lock_sock_nested(struct sock *sk, int subclass);
1607
lock_sock(struct sock * sk)1608 static inline void lock_sock(struct sock *sk)
1609 {
1610 lock_sock_nested(sk, 0);
1611 }
1612
1613 void __lock_sock(struct sock *sk);
1614 void __release_sock(struct sock *sk);
1615 void release_sock(struct sock *sk);
1616
1617 /* BH context may only use the following locking interface. */
1618 #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock))
1619 #define bh_lock_sock_nested(__sk) \
1620 spin_lock_nested(&((__sk)->sk_lock.slock), \
1621 SINGLE_DEPTH_NESTING)
1622 #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock))
1623
1624 bool lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock);
1625
1626 /**
1627 * unlock_sock_fast - complement of lock_sock_fast
1628 * @sk: socket
1629 * @slow: slow mode
1630 *
1631 * fast unlock socket for user context.
1632 * If slow mode is on, we call regular release_sock()
1633 */
unlock_sock_fast(struct sock * sk,bool slow)1634 static inline void unlock_sock_fast(struct sock *sk, bool slow)
1635 __releases(&sk->sk_lock.slock)
1636 {
1637 if (slow) {
1638 release_sock(sk);
1639 __release(&sk->sk_lock.slock);
1640 } else {
1641 spin_unlock_bh(&sk->sk_lock.slock);
1642 }
1643 }
1644
1645 /* Used by processes to "lock" a socket state, so that
1646 * interrupts and bottom half handlers won't change it
1647 * from under us. It essentially blocks any incoming
1648 * packets, so that we won't get any new data or any
1649 * packets that change the state of the socket.
1650 *
1651 * While locked, BH processing will add new packets to
1652 * the backlog queue. This queue is processed by the
1653 * owner of the socket lock right before it is released.
1654 *
1655 * Since ~2.3.5 it is also exclusive sleep lock serializing
1656 * accesses from user process context.
1657 */
1658
sock_owned_by_me(const struct sock * sk)1659 static inline void sock_owned_by_me(const struct sock *sk)
1660 {
1661 #ifdef CONFIG_LOCKDEP
1662 WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
1663 #endif
1664 }
1665
sock_owned_by_user(const struct sock * sk)1666 static inline bool sock_owned_by_user(const struct sock *sk)
1667 {
1668 sock_owned_by_me(sk);
1669 return sk->sk_lock.owned;
1670 }
1671
sock_owned_by_user_nocheck(const struct sock * sk)1672 static inline bool sock_owned_by_user_nocheck(const struct sock *sk)
1673 {
1674 return sk->sk_lock.owned;
1675 }
1676
1677 /* no reclassification while locks are held */
sock_allow_reclassification(const struct sock * csk)1678 static inline bool sock_allow_reclassification(const struct sock *csk)
1679 {
1680 struct sock *sk = (struct sock *)csk;
1681
1682 return !sk->sk_lock.owned && !spin_is_locked(&sk->sk_lock.slock);
1683 }
1684
1685 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1686 struct proto *prot, int kern);
1687 void sk_free(struct sock *sk);
1688 void sk_destruct(struct sock *sk);
1689 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
1690 void sk_free_unlock_clone(struct sock *sk);
1691
1692 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1693 gfp_t priority);
1694 void __sock_wfree(struct sk_buff *skb);
1695 void sock_wfree(struct sk_buff *skb);
1696 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1697 gfp_t priority);
1698 void skb_orphan_partial(struct sk_buff *skb);
1699 void sock_rfree(struct sk_buff *skb);
1700 void sock_efree(struct sk_buff *skb);
1701 #ifdef CONFIG_INET
1702 void sock_edemux(struct sk_buff *skb);
1703 void sock_pfree(struct sk_buff *skb);
1704 #else
1705 #define sock_edemux sock_efree
1706 #endif
1707
1708 int sock_setsockopt(struct socket *sock, int level, int op,
1709 sockptr_t optval, unsigned int optlen);
1710
1711 int sock_getsockopt(struct socket *sock, int level, int op,
1712 char __user *optval, int __user *optlen);
1713 int sock_gettstamp(struct socket *sock, void __user *userstamp,
1714 bool timeval, bool time32);
1715 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1716 int noblock, int *errcode);
1717 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1718 unsigned long data_len, int noblock,
1719 int *errcode, int max_page_order);
1720 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
1721 void sock_kfree_s(struct sock *sk, void *mem, int size);
1722 void sock_kzfree_s(struct sock *sk, void *mem, int size);
1723 void sk_send_sigurg(struct sock *sk);
1724
1725 struct sockcm_cookie {
1726 u64 transmit_time;
1727 u32 mark;
1728 u16 tsflags;
1729 };
1730
sockcm_init(struct sockcm_cookie * sockc,const struct sock * sk)1731 static inline void sockcm_init(struct sockcm_cookie *sockc,
1732 const struct sock *sk)
1733 {
1734 *sockc = (struct sockcm_cookie) { .tsflags = sk->sk_tsflags };
1735 }
1736
1737 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
1738 struct sockcm_cookie *sockc);
1739 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1740 struct sockcm_cookie *sockc);
1741
1742 /*
1743 * Functions to fill in entries in struct proto_ops when a protocol
1744 * does not implement a particular function.
1745 */
1746 int sock_no_bind(struct socket *, struct sockaddr *, int);
1747 int sock_no_connect(struct socket *, struct sockaddr *, int, int);
1748 int sock_no_socketpair(struct socket *, struct socket *);
1749 int sock_no_accept(struct socket *, struct socket *, int, bool);
1750 int sock_no_getname(struct socket *, struct sockaddr *, int);
1751 int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
1752 int sock_no_listen(struct socket *, int);
1753 int sock_no_shutdown(struct socket *, int);
1754 int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
1755 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
1756 int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
1757 int sock_no_mmap(struct file *file, struct socket *sock,
1758 struct vm_area_struct *vma);
1759 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset,
1760 size_t size, int flags);
1761 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
1762 int offset, size_t size, int flags);
1763
1764 /*
1765 * Functions to fill in entries in struct proto_ops when a protocol
1766 * uses the inet style.
1767 */
1768 int sock_common_getsockopt(struct socket *sock, int level, int optname,
1769 char __user *optval, int __user *optlen);
1770 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1771 int flags);
1772 int sock_common_setsockopt(struct socket *sock, int level, int optname,
1773 sockptr_t optval, unsigned int optlen);
1774
1775 void sk_common_release(struct sock *sk);
1776
1777 /*
1778 * Default socket callbacks and setup code
1779 */
1780
1781 /* Initialise core socket variables */
1782 void sock_init_data(struct socket *sock, struct sock *sk);
1783
1784 /*
1785 * Socket reference counting postulates.
1786 *
1787 * * Each user of socket SHOULD hold a reference count.
1788 * * Each access point to socket (an hash table bucket, reference from a list,
1789 * running timer, skb in flight MUST hold a reference count.
1790 * * When reference count hits 0, it means it will never increase back.
1791 * * When reference count hits 0, it means that no references from
1792 * outside exist to this socket and current process on current CPU
1793 * is last user and may/should destroy this socket.
1794 * * sk_free is called from any context: process, BH, IRQ. When
1795 * it is called, socket has no references from outside -> sk_free
1796 * may release descendant resources allocated by the socket, but
1797 * to the time when it is called, socket is NOT referenced by any
1798 * hash tables, lists etc.
1799 * * Packets, delivered from outside (from network or from another process)
1800 * and enqueued on receive/error queues SHOULD NOT grab reference count,
1801 * when they sit in queue. Otherwise, packets will leak to hole, when
1802 * socket is looked up by one cpu and unhasing is made by another CPU.
1803 * It is true for udp/raw, netlink (leak to receive and error queues), tcp
1804 * (leak to backlog). Packet socket does all the processing inside
1805 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1806 * use separate SMP lock, so that they are prone too.
1807 */
1808
1809 /* Ungrab socket and destroy it, if it was the last reference. */
sock_put(struct sock * sk)1810 static inline void sock_put(struct sock *sk)
1811 {
1812 if (refcount_dec_and_test(&sk->sk_refcnt))
1813 sk_free(sk);
1814 }
1815 /* Generic version of sock_put(), dealing with all sockets
1816 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
1817 */
1818 void sock_gen_put(struct sock *sk);
1819
1820 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested,
1821 unsigned int trim_cap, bool refcounted);
sk_receive_skb(struct sock * sk,struct sk_buff * skb,const int nested)1822 static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1823 const int nested)
1824 {
1825 return __sk_receive_skb(sk, skb, nested, 1, true);
1826 }
1827
sk_tx_queue_set(struct sock * sk,int tx_queue)1828 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1829 {
1830 /* sk_tx_queue_mapping accept only upto a 16-bit value */
1831 if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX))
1832 return;
1833 sk->sk_tx_queue_mapping = tx_queue;
1834 }
1835
1836 #define NO_QUEUE_MAPPING USHRT_MAX
1837
sk_tx_queue_clear(struct sock * sk)1838 static inline void sk_tx_queue_clear(struct sock *sk)
1839 {
1840 sk->sk_tx_queue_mapping = NO_QUEUE_MAPPING;
1841 }
1842
sk_tx_queue_get(const struct sock * sk)1843 static inline int sk_tx_queue_get(const struct sock *sk)
1844 {
1845 if (sk && sk->sk_tx_queue_mapping != NO_QUEUE_MAPPING)
1846 return sk->sk_tx_queue_mapping;
1847
1848 return -1;
1849 }
1850
sk_rx_queue_set(struct sock * sk,const struct sk_buff * skb)1851 static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb)
1852 {
1853 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1854 if (skb_rx_queue_recorded(skb)) {
1855 u16 rx_queue = skb_get_rx_queue(skb);
1856
1857 if (WARN_ON_ONCE(rx_queue == NO_QUEUE_MAPPING))
1858 return;
1859
1860 sk->sk_rx_queue_mapping = rx_queue;
1861 }
1862 #endif
1863 }
1864
sk_rx_queue_clear(struct sock * sk)1865 static inline void sk_rx_queue_clear(struct sock *sk)
1866 {
1867 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1868 sk->sk_rx_queue_mapping = NO_QUEUE_MAPPING;
1869 #endif
1870 }
1871
sk_rx_queue_get(const struct sock * sk)1872 static inline int sk_rx_queue_get(const struct sock *sk)
1873 {
1874 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1875 if (sk && sk->sk_rx_queue_mapping != NO_QUEUE_MAPPING)
1876 return sk->sk_rx_queue_mapping;
1877 #endif
1878
1879 return -1;
1880 }
1881
sk_set_socket(struct sock * sk,struct socket * sock)1882 static inline void sk_set_socket(struct sock *sk, struct socket *sock)
1883 {
1884 sk->sk_socket = sock;
1885 }
1886
sk_sleep(struct sock * sk)1887 static inline wait_queue_head_t *sk_sleep(struct sock *sk)
1888 {
1889 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
1890 return &rcu_dereference_raw(sk->sk_wq)->wait;
1891 }
1892 /* Detach socket from process context.
1893 * Announce socket dead, detach it from wait queue and inode.
1894 * Note that parent inode held reference count on this struct sock,
1895 * we do not release it in this function, because protocol
1896 * probably wants some additional cleanups or even continuing
1897 * to work with this socket (TCP).
1898 */
sock_orphan(struct sock * sk)1899 static inline void sock_orphan(struct sock *sk)
1900 {
1901 write_lock_bh(&sk->sk_callback_lock);
1902 sock_set_flag(sk, SOCK_DEAD);
1903 sk_set_socket(sk, NULL);
1904 sk->sk_wq = NULL;
1905 write_unlock_bh(&sk->sk_callback_lock);
1906 }
1907
sock_graft(struct sock * sk,struct socket * parent)1908 static inline void sock_graft(struct sock *sk, struct socket *parent)
1909 {
1910 WARN_ON(parent->sk);
1911 write_lock_bh(&sk->sk_callback_lock);
1912 rcu_assign_pointer(sk->sk_wq, &parent->wq);
1913 parent->sk = sk;
1914 sk_set_socket(sk, parent);
1915 sk->sk_uid = SOCK_INODE(parent)->i_uid;
1916 security_sock_graft(sk, parent);
1917 write_unlock_bh(&sk->sk_callback_lock);
1918 }
1919
1920 kuid_t sock_i_uid(struct sock *sk);
1921 unsigned long sock_i_ino(struct sock *sk);
1922
sock_net_uid(const struct net * net,const struct sock * sk)1923 static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk)
1924 {
1925 return sk ? sk->sk_uid : make_kuid(net->user_ns, 0);
1926 }
1927
net_tx_rndhash(void)1928 static inline u32 net_tx_rndhash(void)
1929 {
1930 u32 v = prandom_u32();
1931
1932 return v ?: 1;
1933 }
1934
sk_set_txhash(struct sock * sk)1935 static inline void sk_set_txhash(struct sock *sk)
1936 {
1937 sk->sk_txhash = net_tx_rndhash();
1938 }
1939
sk_rethink_txhash(struct sock * sk)1940 static inline bool sk_rethink_txhash(struct sock *sk)
1941 {
1942 if (sk->sk_txhash) {
1943 sk_set_txhash(sk);
1944 return true;
1945 }
1946 return false;
1947 }
1948
1949 static inline struct dst_entry *
__sk_dst_get(struct sock * sk)1950 __sk_dst_get(struct sock *sk)
1951 {
1952 return rcu_dereference_check(sk->sk_dst_cache,
1953 lockdep_sock_is_held(sk));
1954 }
1955
1956 static inline struct dst_entry *
sk_dst_get(struct sock * sk)1957 sk_dst_get(struct sock *sk)
1958 {
1959 struct dst_entry *dst;
1960
1961 rcu_read_lock();
1962 dst = rcu_dereference(sk->sk_dst_cache);
1963 if (dst && !atomic_inc_not_zero(&dst->__refcnt))
1964 dst = NULL;
1965 rcu_read_unlock();
1966 return dst;
1967 }
1968
__dst_negative_advice(struct sock * sk)1969 static inline void __dst_negative_advice(struct sock *sk)
1970 {
1971 struct dst_entry *ndst, *dst = __sk_dst_get(sk);
1972
1973 if (dst && dst->ops->negative_advice) {
1974 ndst = dst->ops->negative_advice(dst);
1975
1976 if (ndst != dst) {
1977 rcu_assign_pointer(sk->sk_dst_cache, ndst);
1978 sk_tx_queue_clear(sk);
1979 sk->sk_dst_pending_confirm = 0;
1980 }
1981 }
1982 }
1983
dst_negative_advice(struct sock * sk)1984 static inline void dst_negative_advice(struct sock *sk)
1985 {
1986 sk_rethink_txhash(sk);
1987 __dst_negative_advice(sk);
1988 }
1989
1990 static inline void
__sk_dst_set(struct sock * sk,struct dst_entry * dst)1991 __sk_dst_set(struct sock *sk, struct dst_entry *dst)
1992 {
1993 struct dst_entry *old_dst;
1994
1995 sk_tx_queue_clear(sk);
1996 sk->sk_dst_pending_confirm = 0;
1997 old_dst = rcu_dereference_protected(sk->sk_dst_cache,
1998 lockdep_sock_is_held(sk));
1999 rcu_assign_pointer(sk->sk_dst_cache, dst);
2000 dst_release(old_dst);
2001 }
2002
2003 static inline void
sk_dst_set(struct sock * sk,struct dst_entry * dst)2004 sk_dst_set(struct sock *sk, struct dst_entry *dst)
2005 {
2006 struct dst_entry *old_dst;
2007
2008 sk_tx_queue_clear(sk);
2009 sk->sk_dst_pending_confirm = 0;
2010 old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst);
2011 dst_release(old_dst);
2012 }
2013
2014 static inline void
__sk_dst_reset(struct sock * sk)2015 __sk_dst_reset(struct sock *sk)
2016 {
2017 __sk_dst_set(sk, NULL);
2018 }
2019
2020 static inline void
sk_dst_reset(struct sock * sk)2021 sk_dst_reset(struct sock *sk)
2022 {
2023 sk_dst_set(sk, NULL);
2024 }
2025
2026 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
2027
2028 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
2029
sk_dst_confirm(struct sock * sk)2030 static inline void sk_dst_confirm(struct sock *sk)
2031 {
2032 if (!READ_ONCE(sk->sk_dst_pending_confirm))
2033 WRITE_ONCE(sk->sk_dst_pending_confirm, 1);
2034 }
2035
sock_confirm_neigh(struct sk_buff * skb,struct neighbour * n)2036 static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n)
2037 {
2038 if (skb_get_dst_pending_confirm(skb)) {
2039 struct sock *sk = skb->sk;
2040 unsigned long now = jiffies;
2041
2042 /* avoid dirtying neighbour */
2043 if (READ_ONCE(n->confirmed) != now)
2044 WRITE_ONCE(n->confirmed, now);
2045 if (sk && READ_ONCE(sk->sk_dst_pending_confirm))
2046 WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2047 }
2048 }
2049
2050 bool sk_mc_loop(struct sock *sk);
2051
sk_can_gso(const struct sock * sk)2052 static inline bool sk_can_gso(const struct sock *sk)
2053 {
2054 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
2055 }
2056
2057 void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
2058
sk_nocaps_add(struct sock * sk,netdev_features_t flags)2059 static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags)
2060 {
2061 sk->sk_route_nocaps |= flags;
2062 sk->sk_route_caps &= ~flags;
2063 }
2064
skb_do_copy_data_nocache(struct sock * sk,struct sk_buff * skb,struct iov_iter * from,char * to,int copy,int offset)2065 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
2066 struct iov_iter *from, char *to,
2067 int copy, int offset)
2068 {
2069 if (skb->ip_summed == CHECKSUM_NONE) {
2070 __wsum csum = 0;
2071 if (!csum_and_copy_from_iter_full(to, copy, &csum, from))
2072 return -EFAULT;
2073 skb->csum = csum_block_add(skb->csum, csum, offset);
2074 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
2075 if (!copy_from_iter_full_nocache(to, copy, from))
2076 return -EFAULT;
2077 } else if (!copy_from_iter_full(to, copy, from))
2078 return -EFAULT;
2079
2080 return 0;
2081 }
2082
skb_add_data_nocache(struct sock * sk,struct sk_buff * skb,struct iov_iter * from,int copy)2083 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
2084 struct iov_iter *from, int copy)
2085 {
2086 int err, offset = skb->len;
2087
2088 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
2089 copy, offset);
2090 if (err)
2091 __skb_trim(skb, offset);
2092
2093 return err;
2094 }
2095
skb_copy_to_page_nocache(struct sock * sk,struct iov_iter * from,struct sk_buff * skb,struct page * page,int off,int copy)2096 static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
2097 struct sk_buff *skb,
2098 struct page *page,
2099 int off, int copy)
2100 {
2101 int err;
2102
2103 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
2104 copy, skb->len);
2105 if (err)
2106 return err;
2107
2108 skb->len += copy;
2109 skb->data_len += copy;
2110 skb->truesize += copy;
2111 sk_wmem_queued_add(sk, copy);
2112 sk_mem_charge(sk, copy);
2113 return 0;
2114 }
2115
2116 /**
2117 * sk_wmem_alloc_get - returns write allocations
2118 * @sk: socket
2119 *
2120 * Return: sk_wmem_alloc minus initial offset of one
2121 */
sk_wmem_alloc_get(const struct sock * sk)2122 static inline int sk_wmem_alloc_get(const struct sock *sk)
2123 {
2124 return refcount_read(&sk->sk_wmem_alloc) - 1;
2125 }
2126
2127 /**
2128 * sk_rmem_alloc_get - returns read allocations
2129 * @sk: socket
2130 *
2131 * Return: sk_rmem_alloc
2132 */
sk_rmem_alloc_get(const struct sock * sk)2133 static inline int sk_rmem_alloc_get(const struct sock *sk)
2134 {
2135 return atomic_read(&sk->sk_rmem_alloc);
2136 }
2137
2138 /**
2139 * sk_has_allocations - check if allocations are outstanding
2140 * @sk: socket
2141 *
2142 * Return: true if socket has write or read allocations
2143 */
sk_has_allocations(const struct sock * sk)2144 static inline bool sk_has_allocations(const struct sock *sk)
2145 {
2146 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
2147 }
2148
2149 /**
2150 * skwq_has_sleeper - check if there are any waiting processes
2151 * @wq: struct socket_wq
2152 *
2153 * Return: true if socket_wq has waiting processes
2154 *
2155 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory
2156 * barrier call. They were added due to the race found within the tcp code.
2157 *
2158 * Consider following tcp code paths::
2159 *
2160 * CPU1 CPU2
2161 * sys_select receive packet
2162 * ... ...
2163 * __add_wait_queue update tp->rcv_nxt
2164 * ... ...
2165 * tp->rcv_nxt check sock_def_readable
2166 * ... {
2167 * schedule rcu_read_lock();
2168 * wq = rcu_dereference(sk->sk_wq);
2169 * if (wq && waitqueue_active(&wq->wait))
2170 * wake_up_interruptible(&wq->wait)
2171 * ...
2172 * }
2173 *
2174 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
2175 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1
2176 * could then endup calling schedule and sleep forever if there are no more
2177 * data on the socket.
2178 *
2179 */
skwq_has_sleeper(struct socket_wq * wq)2180 static inline bool skwq_has_sleeper(struct socket_wq *wq)
2181 {
2182 return wq && wq_has_sleeper(&wq->wait);
2183 }
2184
2185 /**
2186 * sock_poll_wait - place memory barrier behind the poll_wait call.
2187 * @filp: file
2188 * @sock: socket to wait on
2189 * @p: poll_table
2190 *
2191 * See the comments in the wq_has_sleeper function.
2192 */
sock_poll_wait(struct file * filp,struct socket * sock,poll_table * p)2193 static inline void sock_poll_wait(struct file *filp, struct socket *sock,
2194 poll_table *p)
2195 {
2196 if (!poll_does_not_wait(p)) {
2197 poll_wait(filp, &sock->wq.wait, p);
2198 /* We need to be sure we are in sync with the
2199 * socket flags modification.
2200 *
2201 * This memory barrier is paired in the wq_has_sleeper.
2202 */
2203 smp_mb();
2204 }
2205 }
2206
skb_set_hash_from_sk(struct sk_buff * skb,struct sock * sk)2207 static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk)
2208 {
2209 if (sk->sk_txhash) {
2210 skb->l4_hash = 1;
2211 skb->hash = sk->sk_txhash;
2212 }
2213 }
2214
2215 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);
2216
2217 /*
2218 * Queue a received datagram if it will fit. Stream and sequenced
2219 * protocols can't normally use this as they need to fit buffers in
2220 * and play with them.
2221 *
2222 * Inlined as it's very short and called for pretty much every
2223 * packet ever received.
2224 */
skb_set_owner_r(struct sk_buff * skb,struct sock * sk)2225 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
2226 {
2227 skb_orphan(skb);
2228 skb->sk = sk;
2229 skb->destructor = sock_rfree;
2230 atomic_add(skb->truesize, &sk->sk_rmem_alloc);
2231 sk_mem_charge(sk, skb->truesize);
2232 }
2233
skb_set_owner_sk_safe(struct sk_buff * skb,struct sock * sk)2234 static inline void skb_set_owner_sk_safe(struct sk_buff *skb, struct sock *sk)
2235 {
2236 if (sk && refcount_inc_not_zero(&sk->sk_refcnt)) {
2237 skb_orphan(skb);
2238 skb->destructor = sock_efree;
2239 skb->sk = sk;
2240 }
2241 }
2242
2243 void sk_reset_timer(struct sock *sk, struct timer_list *timer,
2244 unsigned long expires);
2245
2246 void sk_stop_timer(struct sock *sk, struct timer_list *timer);
2247
2248 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer);
2249
2250 int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue,
2251 struct sk_buff *skb, unsigned int flags,
2252 void (*destructor)(struct sock *sk,
2253 struct sk_buff *skb));
2254 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2255 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2256
2257 int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2258 struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
2259
2260 /*
2261 * Recover an error report and clear atomically
2262 */
2263
sock_error(struct sock * sk)2264 static inline int sock_error(struct sock *sk)
2265 {
2266 int err;
2267 if (likely(!sk->sk_err))
2268 return 0;
2269 err = xchg(&sk->sk_err, 0);
2270 return -err;
2271 }
2272
sock_wspace(struct sock * sk)2273 static inline unsigned long sock_wspace(struct sock *sk)
2274 {
2275 int amt = 0;
2276
2277 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2278 amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc);
2279 if (amt < 0)
2280 amt = 0;
2281 }
2282 return amt;
2283 }
2284
2285 /* Note:
2286 * We use sk->sk_wq_raw, from contexts knowing this
2287 * pointer is not NULL and cannot disappear/change.
2288 */
sk_set_bit(int nr,struct sock * sk)2289 static inline void sk_set_bit(int nr, struct sock *sk)
2290 {
2291 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2292 !sock_flag(sk, SOCK_FASYNC))
2293 return;
2294
2295 set_bit(nr, &sk->sk_wq_raw->flags);
2296 }
2297
sk_clear_bit(int nr,struct sock * sk)2298 static inline void sk_clear_bit(int nr, struct sock *sk)
2299 {
2300 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2301 !sock_flag(sk, SOCK_FASYNC))
2302 return;
2303
2304 clear_bit(nr, &sk->sk_wq_raw->flags);
2305 }
2306
sk_wake_async(const struct sock * sk,int how,int band)2307 static inline void sk_wake_async(const struct sock *sk, int how, int band)
2308 {
2309 if (sock_flag(sk, SOCK_FASYNC)) {
2310 rcu_read_lock();
2311 sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2312 rcu_read_unlock();
2313 }
2314 }
2315
2316 /* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2317 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2318 * Note: for send buffers, TCP works better if we can build two skbs at
2319 * minimum.
2320 */
2321 #define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2322
2323 #define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2)
2324 #define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE
2325
sk_stream_moderate_sndbuf(struct sock * sk)2326 static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2327 {
2328 u32 val;
2329
2330 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)
2331 return;
2332
2333 val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2334
2335 WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF));
2336 }
2337
2338 struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp,
2339 bool force_schedule);
2340
2341 /**
2342 * sk_page_frag - return an appropriate page_frag
2343 * @sk: socket
2344 *
2345 * Use the per task page_frag instead of the per socket one for
2346 * optimization when we know that we're in the normal context and owns
2347 * everything that's associated with %current.
2348 *
2349 * gfpflags_allow_blocking() isn't enough here as direct reclaim may nest
2350 * inside other socket operations and end up recursing into sk_page_frag()
2351 * while it's already in use.
2352 *
2353 * Return: a per task page_frag if context allows that,
2354 * otherwise a per socket one.
2355 */
sk_page_frag(struct sock * sk)2356 static inline struct page_frag *sk_page_frag(struct sock *sk)
2357 {
2358 if (gfpflags_normal_context(sk->sk_allocation))
2359 return ¤t->task_frag;
2360
2361 return &sk->sk_frag;
2362 }
2363
2364 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2365
2366 /*
2367 * Default write policy as shown to user space via poll/select/SIGIO
2368 */
sock_writeable(const struct sock * sk)2369 static inline bool sock_writeable(const struct sock *sk)
2370 {
2371 return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1);
2372 }
2373
gfp_any(void)2374 static inline gfp_t gfp_any(void)
2375 {
2376 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2377 }
2378
sock_rcvtimeo(const struct sock * sk,bool noblock)2379 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2380 {
2381 return noblock ? 0 : sk->sk_rcvtimeo;
2382 }
2383
sock_sndtimeo(const struct sock * sk,bool noblock)2384 static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2385 {
2386 return noblock ? 0 : sk->sk_sndtimeo;
2387 }
2388
sock_rcvlowat(const struct sock * sk,int waitall,int len)2389 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2390 {
2391 int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len);
2392
2393 return v ?: 1;
2394 }
2395
2396 /* Alas, with timeout socket operations are not restartable.
2397 * Compare this to poll().
2398 */
sock_intr_errno(long timeo)2399 static inline int sock_intr_errno(long timeo)
2400 {
2401 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2402 }
2403
2404 struct sock_skb_cb {
2405 u32 dropcount;
2406 };
2407
2408 /* Store sock_skb_cb at the end of skb->cb[] so protocol families
2409 * using skb->cb[] would keep using it directly and utilize its
2410 * alignement guarantee.
2411 */
2412 #define SOCK_SKB_CB_OFFSET ((sizeof_field(struct sk_buff, cb) - \
2413 sizeof(struct sock_skb_cb)))
2414
2415 #define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
2416 SOCK_SKB_CB_OFFSET))
2417
2418 #define sock_skb_cb_check_size(size) \
2419 BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
2420
2421 static inline void
sock_skb_set_dropcount(const struct sock * sk,struct sk_buff * skb)2422 sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
2423 {
2424 SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ?
2425 atomic_read(&sk->sk_drops) : 0;
2426 }
2427
sk_drops_add(struct sock * sk,const struct sk_buff * skb)2428 static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb)
2429 {
2430 int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs);
2431
2432 atomic_add(segs, &sk->sk_drops);
2433 }
2434
sock_read_timestamp(struct sock * sk)2435 static inline ktime_t sock_read_timestamp(struct sock *sk)
2436 {
2437 #if BITS_PER_LONG==32
2438 unsigned int seq;
2439 ktime_t kt;
2440
2441 do {
2442 seq = read_seqbegin(&sk->sk_stamp_seq);
2443 kt = sk->sk_stamp;
2444 } while (read_seqretry(&sk->sk_stamp_seq, seq));
2445
2446 return kt;
2447 #else
2448 return READ_ONCE(sk->sk_stamp);
2449 #endif
2450 }
2451
sock_write_timestamp(struct sock * sk,ktime_t kt)2452 static inline void sock_write_timestamp(struct sock *sk, ktime_t kt)
2453 {
2454 #if BITS_PER_LONG==32
2455 write_seqlock(&sk->sk_stamp_seq);
2456 sk->sk_stamp = kt;
2457 write_sequnlock(&sk->sk_stamp_seq);
2458 #else
2459 WRITE_ONCE(sk->sk_stamp, kt);
2460 #endif
2461 }
2462
2463 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2464 struct sk_buff *skb);
2465 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2466 struct sk_buff *skb);
2467
2468 static inline void
sock_recv_timestamp(struct msghdr * msg,struct sock * sk,struct sk_buff * skb)2469 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2470 {
2471 ktime_t kt = skb->tstamp;
2472 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2473
2474 /*
2475 * generate control messages if
2476 * - receive time stamping in software requested
2477 * - software time stamp available and wanted
2478 * - hardware time stamps available and wanted
2479 */
2480 if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2481 (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
2482 (kt && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
2483 (hwtstamps->hwtstamp &&
2484 (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
2485 __sock_recv_timestamp(msg, sk, skb);
2486 else
2487 sock_write_timestamp(sk, kt);
2488
2489 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid)
2490 __sock_recv_wifi_status(msg, sk, skb);
2491 }
2492
2493 void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2494 struct sk_buff *skb);
2495
2496 #define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC)
sock_recv_ts_and_drops(struct msghdr * msg,struct sock * sk,struct sk_buff * skb)2497 static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2498 struct sk_buff *skb)
2499 {
2500 #define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \
2501 (1UL << SOCK_RCVTSTAMP))
2502 #define TSFLAGS_ANY (SOF_TIMESTAMPING_SOFTWARE | \
2503 SOF_TIMESTAMPING_RAW_HARDWARE)
2504
2505 if (sk->sk_flags & FLAGS_TS_OR_DROPS || sk->sk_tsflags & TSFLAGS_ANY)
2506 __sock_recv_ts_and_drops(msg, sk, skb);
2507 else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP)))
2508 sock_write_timestamp(sk, skb->tstamp);
2509 else if (unlikely(sk->sk_stamp == SK_DEFAULT_STAMP))
2510 sock_write_timestamp(sk, 0);
2511 }
2512
2513 void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags);
2514
2515 /**
2516 * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2517 * @sk: socket sending this packet
2518 * @tsflags: timestamping flags to use
2519 * @tx_flags: completed with instructions for time stamping
2520 * @tskey: filled in with next sk_tskey (not for TCP, which uses seqno)
2521 *
2522 * Note: callers should take care of initial ``*tx_flags`` value (usually 0)
2523 */
_sock_tx_timestamp(struct sock * sk,__u16 tsflags,__u8 * tx_flags,__u32 * tskey)2524 static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2525 __u8 *tx_flags, __u32 *tskey)
2526 {
2527 if (unlikely(tsflags)) {
2528 __sock_tx_timestamp(tsflags, tx_flags);
2529 if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey &&
2530 tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK)
2531 *tskey = sk->sk_tskey++;
2532 }
2533 if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
2534 *tx_flags |= SKBTX_WIFI_STATUS;
2535 }
2536
sock_tx_timestamp(struct sock * sk,__u16 tsflags,__u8 * tx_flags)2537 static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2538 __u8 *tx_flags)
2539 {
2540 _sock_tx_timestamp(sk, tsflags, tx_flags, NULL);
2541 }
2542
skb_setup_tx_timestamp(struct sk_buff * skb,__u16 tsflags)2543 static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags)
2544 {
2545 _sock_tx_timestamp(skb->sk, tsflags, &skb_shinfo(skb)->tx_flags,
2546 &skb_shinfo(skb)->tskey);
2547 }
2548
2549 DECLARE_STATIC_KEY_FALSE(tcp_rx_skb_cache_key);
2550 /**
2551 * sk_eat_skb - Release a skb if it is no longer needed
2552 * @sk: socket to eat this skb from
2553 * @skb: socket buffer to eat
2554 *
2555 * This routine must be called with interrupts disabled or with the socket
2556 * locked so that the sk_buff queue operation is ok.
2557 */
sk_eat_skb(struct sock * sk,struct sk_buff * skb)2558 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
2559 {
2560 __skb_unlink(skb, &sk->sk_receive_queue);
2561 if (static_branch_unlikely(&tcp_rx_skb_cache_key) &&
2562 !sk->sk_rx_skb_cache) {
2563 sk->sk_rx_skb_cache = skb;
2564 skb_orphan(skb);
2565 return;
2566 }
2567 __kfree_skb(skb);
2568 }
2569
2570 static inline
sock_net(const struct sock * sk)2571 struct net *sock_net(const struct sock *sk)
2572 {
2573 return read_pnet(&sk->sk_net);
2574 }
2575
2576 static inline
sock_net_set(struct sock * sk,struct net * net)2577 void sock_net_set(struct sock *sk, struct net *net)
2578 {
2579 write_pnet(&sk->sk_net, net);
2580 }
2581
2582 static inline bool
skb_sk_is_prefetched(struct sk_buff * skb)2583 skb_sk_is_prefetched(struct sk_buff *skb)
2584 {
2585 #ifdef CONFIG_INET
2586 return skb->destructor == sock_pfree;
2587 #else
2588 return false;
2589 #endif /* CONFIG_INET */
2590 }
2591
2592 /* This helper checks if a socket is a full socket,
2593 * ie _not_ a timewait or request socket.
2594 */
sk_fullsock(const struct sock * sk)2595 static inline bool sk_fullsock(const struct sock *sk)
2596 {
2597 return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
2598 }
2599
2600 static inline bool
sk_is_refcounted(struct sock * sk)2601 sk_is_refcounted(struct sock *sk)
2602 {
2603 /* Only full sockets have sk->sk_flags. */
2604 return !sk_fullsock(sk) || !sock_flag(sk, SOCK_RCU_FREE);
2605 }
2606
2607 /**
2608 * skb_steal_sock - steal a socket from an sk_buff
2609 * @skb: sk_buff to steal the socket from
2610 * @refcounted: is set to true if the socket is reference-counted
2611 */
2612 static inline struct sock *
skb_steal_sock(struct sk_buff * skb,bool * refcounted)2613 skb_steal_sock(struct sk_buff *skb, bool *refcounted)
2614 {
2615 if (skb->sk) {
2616 struct sock *sk = skb->sk;
2617
2618 *refcounted = true;
2619 if (skb_sk_is_prefetched(skb))
2620 *refcounted = sk_is_refcounted(sk);
2621 skb->destructor = NULL;
2622 skb->sk = NULL;
2623 return sk;
2624 }
2625 *refcounted = false;
2626 return NULL;
2627 }
2628
2629 /* Checks if this SKB belongs to an HW offloaded socket
2630 * and whether any SW fallbacks are required based on dev.
2631 * Check decrypted mark in case skb_orphan() cleared socket.
2632 */
sk_validate_xmit_skb(struct sk_buff * skb,struct net_device * dev)2633 static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb,
2634 struct net_device *dev)
2635 {
2636 #ifdef CONFIG_SOCK_VALIDATE_XMIT
2637 struct sock *sk = skb->sk;
2638
2639 if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) {
2640 skb = sk->sk_validate_xmit_skb(sk, dev, skb);
2641 #ifdef CONFIG_TLS_DEVICE
2642 } else if (unlikely(skb->decrypted)) {
2643 pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n");
2644 kfree_skb(skb);
2645 skb = NULL;
2646 #endif
2647 }
2648 #endif
2649
2650 return skb;
2651 }
2652
2653 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
2654 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
2655 */
sk_listener(const struct sock * sk)2656 static inline bool sk_listener(const struct sock *sk)
2657 {
2658 return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
2659 }
2660
2661 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag);
2662 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
2663 int type);
2664
2665 bool sk_ns_capable(const struct sock *sk,
2666 struct user_namespace *user_ns, int cap);
2667 bool sk_capable(const struct sock *sk, int cap);
2668 bool sk_net_capable(const struct sock *sk, int cap);
2669
2670 void sk_get_meminfo(const struct sock *sk, u32 *meminfo);
2671
2672 /* Take into consideration the size of the struct sk_buff overhead in the
2673 * determination of these values, since that is non-constant across
2674 * platforms. This makes socket queueing behavior and performance
2675 * not depend upon such differences.
2676 */
2677 #define _SK_MEM_PACKETS 256
2678 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256)
2679 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2680 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2681
2682 extern __u32 sysctl_wmem_max;
2683 extern __u32 sysctl_rmem_max;
2684
2685 extern int sysctl_tstamp_allow_data;
2686 extern int sysctl_optmem_max;
2687
2688 extern __u32 sysctl_wmem_default;
2689 extern __u32 sysctl_rmem_default;
2690
2691 DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2692
sk_get_wmem0(const struct sock * sk,const struct proto * proto)2693 static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto)
2694 {
2695 /* Does this proto have per netns sysctl_wmem ? */
2696 if (proto->sysctl_wmem_offset)
2697 return *(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset);
2698
2699 return *proto->sysctl_wmem;
2700 }
2701
sk_get_rmem0(const struct sock * sk,const struct proto * proto)2702 static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto)
2703 {
2704 /* Does this proto have per netns sysctl_rmem ? */
2705 if (proto->sysctl_rmem_offset)
2706 return *(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset);
2707
2708 return *proto->sysctl_rmem;
2709 }
2710
2711 /* Default TCP Small queue budget is ~1 ms of data (1sec >> 10)
2712 * Some wifi drivers need to tweak it to get more chunks.
2713 * They can use this helper from their ndo_start_xmit()
2714 */
sk_pacing_shift_update(struct sock * sk,int val)2715 static inline void sk_pacing_shift_update(struct sock *sk, int val)
2716 {
2717 if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val)
2718 return;
2719 WRITE_ONCE(sk->sk_pacing_shift, val);
2720 }
2721
2722 /* if a socket is bound to a device, check that the given device
2723 * index is either the same or that the socket is bound to an L3
2724 * master device and the given device index is also enslaved to
2725 * that L3 master
2726 */
sk_dev_equal_l3scope(struct sock * sk,int dif)2727 static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif)
2728 {
2729 int mdif;
2730
2731 if (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dif)
2732 return true;
2733
2734 mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif);
2735 if (mdif && mdif == sk->sk_bound_dev_if)
2736 return true;
2737
2738 return false;
2739 }
2740
2741 void sock_def_readable(struct sock *sk);
2742
2743 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk);
2744 void sock_enable_timestamps(struct sock *sk);
2745 void sock_no_linger(struct sock *sk);
2746 void sock_set_keepalive(struct sock *sk);
2747 void sock_set_priority(struct sock *sk, u32 priority);
2748 void sock_set_rcvbuf(struct sock *sk, int val);
2749 void sock_set_mark(struct sock *sk, u32 val);
2750 void sock_set_reuseaddr(struct sock *sk);
2751 void sock_set_reuseport(struct sock *sk);
2752 void sock_set_sndtimeo(struct sock *sk, s64 secs);
2753
2754 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len);
2755
2756 #endif /* _SOCK_H */
2757