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 63 #include <linux/atomic.h> 64 #include <linux/refcount.h> 65 #include <net/dst.h> 66 #include <net/checksum.h> 67 #include <net/tcp_states.h> 68 #include <linux/net_tstamp.h> 69 #include <net/smc.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) 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_hash: hash value used with various protocol lookup tables 122 * @skc_u16hashes: two u16 hash values used by UDP lookup tables 123 * @skc_dport: placeholder for inet_dport/tw_dport 124 * @skc_num: placeholder for inet_num/tw_num 125 * @skc_family: network address family 126 * @skc_state: Connection state 127 * @skc_reuse: %SO_REUSEADDR setting 128 * @skc_reuseport: %SO_REUSEPORT setting 129 * @skc_bound_dev_if: bound device index if != 0 130 * @skc_bind_node: bind hash linkage for various protocol lookup tables 131 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol 132 * @skc_prot: protocol handlers inside a network family 133 * @skc_net: reference to the network namespace of this socket 134 * @skc_node: main hash linkage for various protocol lookup tables 135 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol 136 * @skc_tx_queue_mapping: tx queue number for this connection 137 * @skc_rx_queue_mapping: rx queue number for this connection 138 * @skc_flags: place holder for sk_flags 139 * %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE, 140 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings 141 * @skc_incoming_cpu: record/match cpu processing incoming packets 142 * @skc_refcnt: reference count 143 * 144 * This is the minimal network layer representation of sockets, the header 145 * for struct sock and struct inet_timewait_sock. 146 */ 147 struct sock_common { 148 /* skc_daddr and skc_rcv_saddr must be grouped on a 8 bytes aligned 149 * address on 64bit arches : cf INET_MATCH() 150 */ 151 union { 152 __addrpair skc_addrpair; 153 struct { 154 __be32 skc_daddr; 155 __be32 skc_rcv_saddr; 156 }; 157 }; 158 union { 159 unsigned int skc_hash; 160 __u16 skc_u16hashes[2]; 161 }; 162 /* skc_dport && skc_num must be grouped as well */ 163 union { 164 __portpair skc_portpair; 165 struct { 166 __be16 skc_dport; 167 __u16 skc_num; 168 }; 169 }; 170 171 unsigned short skc_family; 172 volatile unsigned char skc_state; 173 unsigned char skc_reuse:4; 174 unsigned char skc_reuseport:1; 175 unsigned char skc_ipv6only:1; 176 unsigned char skc_net_refcnt:1; 177 int skc_bound_dev_if; 178 union { 179 struct hlist_node skc_bind_node; 180 struct hlist_node skc_portaddr_node; 181 }; 182 struct proto *skc_prot; 183 possible_net_t skc_net; 184 185 #if IS_ENABLED(CONFIG_IPV6) 186 struct in6_addr skc_v6_daddr; 187 struct in6_addr skc_v6_rcv_saddr; 188 #endif 189 190 atomic64_t skc_cookie; 191 192 /* following fields are padding to force 193 * offset(struct sock, sk_refcnt) == 128 on 64bit arches 194 * assuming IPV6 is enabled. We use this padding differently 195 * for different kind of 'sockets' 196 */ 197 union { 198 unsigned long skc_flags; 199 struct sock *skc_listener; /* request_sock */ 200 struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */ 201 }; 202 /* 203 * fields between dontcopy_begin/dontcopy_end 204 * are not copied in sock_copy() 205 */ 206 /* private: */ 207 int skc_dontcopy_begin[0]; 208 /* public: */ 209 union { 210 struct hlist_node skc_node; 211 struct hlist_nulls_node skc_nulls_node; 212 }; 213 unsigned short skc_tx_queue_mapping; 214 #ifdef CONFIG_XPS 215 unsigned short skc_rx_queue_mapping; 216 #endif 217 union { 218 int skc_incoming_cpu; 219 u32 skc_rcv_wnd; 220 u32 skc_tw_rcv_nxt; /* struct tcp_timewait_sock */ 221 }; 222 223 refcount_t skc_refcnt; 224 /* private: */ 225 int skc_dontcopy_end[0]; 226 union { 227 u32 skc_rxhash; 228 u32 skc_window_clamp; 229 u32 skc_tw_snd_nxt; /* struct tcp_timewait_sock */ 230 }; 231 /* public: */ 232 }; 233 234 struct bpf_sk_storage; 235 236 /** 237 * struct sock - network layer representation of sockets 238 * @__sk_common: shared layout with inet_timewait_sock 239 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN 240 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings 241 * @sk_lock: synchronizer 242 * @sk_kern_sock: True if sock is using kernel lock classes 243 * @sk_rcvbuf: size of receive buffer in bytes 244 * @sk_wq: sock wait queue and async head 245 * @sk_rx_dst: receive input route used by early demux 246 * @sk_dst_cache: destination cache 247 * @sk_dst_pending_confirm: need to confirm neighbour 248 * @sk_policy: flow policy 249 * @sk_receive_queue: incoming packets 250 * @sk_wmem_alloc: transmit queue bytes committed 251 * @sk_tsq_flags: TCP Small Queues flags 252 * @sk_write_queue: Packet sending queue 253 * @sk_omem_alloc: "o" is "option" or "other" 254 * @sk_wmem_queued: persistent queue size 255 * @sk_forward_alloc: space allocated forward 256 * @sk_napi_id: id of the last napi context to receive data for sk 257 * @sk_ll_usec: usecs to busypoll when there is no data 258 * @sk_allocation: allocation mode 259 * @sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler) 260 * @sk_pacing_status: Pacing status (requested, handled by sch_fq) 261 * @sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE) 262 * @sk_sndbuf: size of send buffer in bytes 263 * @__sk_flags_offset: empty field used to determine location of bitfield 264 * @sk_padding: unused element for alignment 265 * @sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets 266 * @sk_no_check_rx: allow zero checksum in RX packets 267 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO) 268 * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK) 269 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4) 270 * @sk_gso_max_size: Maximum GSO segment size to build 271 * @sk_gso_max_segs: Maximum number of GSO segments 272 * @sk_pacing_shift: scaling factor for TCP Small Queues 273 * @sk_lingertime: %SO_LINGER l_linger setting 274 * @sk_backlog: always used with the per-socket spinlock held 275 * @sk_callback_lock: used with the callbacks in the end of this struct 276 * @sk_error_queue: rarely used 277 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt, 278 * IPV6_ADDRFORM for instance) 279 * @sk_err: last error 280 * @sk_err_soft: errors that don't cause failure but are the cause of a 281 * persistent failure not just 'timed out' 282 * @sk_drops: raw/udp drops counter 283 * @sk_ack_backlog: current listen backlog 284 * @sk_max_ack_backlog: listen backlog set in listen() 285 * @sk_uid: user id of owner 286 * @sk_priority: %SO_PRIORITY setting 287 * @sk_type: socket type (%SOCK_STREAM, etc) 288 * @sk_protocol: which protocol this socket belongs in this network family 289 * @sk_peer_pid: &struct pid for this socket's peer 290 * @sk_peer_cred: %SO_PEERCRED setting 291 * @sk_rcvlowat: %SO_RCVLOWAT setting 292 * @sk_rcvtimeo: %SO_RCVTIMEO setting 293 * @sk_sndtimeo: %SO_SNDTIMEO setting 294 * @sk_txhash: computed flow hash for use on transmit 295 * @sk_filter: socket filtering instructions 296 * @sk_timer: sock cleanup timer 297 * @sk_stamp: time stamp of last packet received 298 * @sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only 299 * @sk_tsflags: SO_TIMESTAMPING socket options 300 * @sk_tskey: counter to disambiguate concurrent tstamp requests 301 * @sk_zckey: counter to order MSG_ZEROCOPY notifications 302 * @sk_socket: Identd and reporting IO signals 303 * @sk_user_data: RPC layer private data 304 * @sk_frag: cached page frag 305 * @sk_peek_off: current peek_offset value 306 * @sk_send_head: front of stuff to transmit 307 * @sk_security: used by security modules 308 * @sk_mark: generic packet mark 309 * @sk_cgrp_data: cgroup data for this cgroup 310 * @sk_memcg: this socket's memory cgroup association 311 * @sk_write_pending: a write to stream socket waits to start 312 * @sk_state_change: callback to indicate change in the state of the sock 313 * @sk_data_ready: callback to indicate there is data to be processed 314 * @sk_write_space: callback to indicate there is bf sending space available 315 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE) 316 * @sk_backlog_rcv: callback to process the backlog 317 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0 318 * @sk_reuseport_cb: reuseport group container 319 * @sk_rcu: used during RCU grace period 320 * @sk_clockid: clockid used by time-based scheduling (SO_TXTIME) 321 * @sk_txtime_deadline_mode: set deadline mode for SO_TXTIME 322 * @sk_txtime_unused: unused txtime flags 323 */ 324 struct sock { 325 /* 326 * Now struct inet_timewait_sock also uses sock_common, so please just 327 * don't add nothing before this first member (__sk_common) --acme 328 */ 329 struct sock_common __sk_common; 330 #define sk_node __sk_common.skc_node 331 #define sk_nulls_node __sk_common.skc_nulls_node 332 #define sk_refcnt __sk_common.skc_refcnt 333 #define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping 334 #ifdef CONFIG_XPS 335 #define sk_rx_queue_mapping __sk_common.skc_rx_queue_mapping 336 #endif 337 338 #define sk_dontcopy_begin __sk_common.skc_dontcopy_begin 339 #define sk_dontcopy_end __sk_common.skc_dontcopy_end 340 #define sk_hash __sk_common.skc_hash 341 #define sk_portpair __sk_common.skc_portpair 342 #define sk_num __sk_common.skc_num 343 #define sk_dport __sk_common.skc_dport 344 #define sk_addrpair __sk_common.skc_addrpair 345 #define sk_daddr __sk_common.skc_daddr 346 #define sk_rcv_saddr __sk_common.skc_rcv_saddr 347 #define sk_family __sk_common.skc_family 348 #define sk_state __sk_common.skc_state 349 #define sk_reuse __sk_common.skc_reuse 350 #define sk_reuseport __sk_common.skc_reuseport 351 #define sk_ipv6only __sk_common.skc_ipv6only 352 #define sk_net_refcnt __sk_common.skc_net_refcnt 353 #define sk_bound_dev_if __sk_common.skc_bound_dev_if 354 #define sk_bind_node __sk_common.skc_bind_node 355 #define sk_prot __sk_common.skc_prot 356 #define sk_net __sk_common.skc_net 357 #define sk_v6_daddr __sk_common.skc_v6_daddr 358 #define sk_v6_rcv_saddr __sk_common.skc_v6_rcv_saddr 359 #define sk_cookie __sk_common.skc_cookie 360 #define sk_incoming_cpu __sk_common.skc_incoming_cpu 361 #define sk_flags __sk_common.skc_flags 362 #define sk_rxhash __sk_common.skc_rxhash 363 364 socket_lock_t sk_lock; 365 atomic_t sk_drops; 366 int sk_rcvlowat; 367 struct sk_buff_head sk_error_queue; 368 struct sk_buff *sk_rx_skb_cache; 369 struct sk_buff_head sk_receive_queue; 370 /* 371 * The backlog queue is special, it is always used with 372 * the per-socket spinlock held and requires low latency 373 * access. Therefore we special case it's implementation. 374 * Note : rmem_alloc is in this structure to fill a hole 375 * on 64bit arches, not because its logically part of 376 * backlog. 377 */ 378 struct { 379 atomic_t rmem_alloc; 380 int len; 381 struct sk_buff *head; 382 struct sk_buff *tail; 383 } sk_backlog; 384 #define sk_rmem_alloc sk_backlog.rmem_alloc 385 386 int sk_forward_alloc; 387 #ifdef CONFIG_NET_RX_BUSY_POLL 388 unsigned int sk_ll_usec; 389 /* ===== mostly read cache line ===== */ 390 unsigned int sk_napi_id; 391 #endif 392 int sk_rcvbuf; 393 394 struct sk_filter __rcu *sk_filter; 395 union { 396 struct socket_wq __rcu *sk_wq; 397 struct socket_wq *sk_wq_raw; 398 }; 399 #ifdef CONFIG_XFRM 400 struct xfrm_policy __rcu *sk_policy[2]; 401 #endif 402 struct dst_entry *sk_rx_dst; 403 struct dst_entry __rcu *sk_dst_cache; 404 atomic_t sk_omem_alloc; 405 int sk_sndbuf; 406 407 /* ===== cache line for TX ===== */ 408 int sk_wmem_queued; 409 refcount_t sk_wmem_alloc; 410 unsigned long sk_tsq_flags; 411 union { 412 struct sk_buff *sk_send_head; 413 struct rb_root tcp_rtx_queue; 414 }; 415 struct sk_buff *sk_tx_skb_cache; 416 struct sk_buff_head sk_write_queue; 417 __s32 sk_peek_off; 418 int sk_write_pending; 419 __u32 sk_dst_pending_confirm; 420 u32 sk_pacing_status; /* see enum sk_pacing */ 421 long sk_sndtimeo; 422 struct timer_list sk_timer; 423 __u32 sk_priority; 424 __u32 sk_mark; 425 unsigned long sk_pacing_rate; /* bytes per second */ 426 unsigned long sk_max_pacing_rate; 427 struct page_frag sk_frag; 428 netdev_features_t sk_route_caps; 429 netdev_features_t sk_route_nocaps; 430 netdev_features_t sk_route_forced_caps; 431 int sk_gso_type; 432 unsigned int sk_gso_max_size; 433 gfp_t sk_allocation; 434 __u32 sk_txhash; 435 436 /* 437 * Because of non atomicity rules, all 438 * changes are protected by socket lock. 439 */ 440 unsigned int __sk_flags_offset[0]; 441 #ifdef __BIG_ENDIAN_BITFIELD 442 #define SK_FL_PROTO_SHIFT 16 443 #define SK_FL_PROTO_MASK 0x00ff0000 444 445 #define SK_FL_TYPE_SHIFT 0 446 #define SK_FL_TYPE_MASK 0x0000ffff 447 #else 448 #define SK_FL_PROTO_SHIFT 8 449 #define SK_FL_PROTO_MASK 0x0000ff00 450 451 #define SK_FL_TYPE_SHIFT 16 452 #define SK_FL_TYPE_MASK 0xffff0000 453 #endif 454 455 unsigned int sk_padding : 1, 456 sk_kern_sock : 1, 457 sk_no_check_tx : 1, 458 sk_no_check_rx : 1, 459 sk_userlocks : 4, 460 sk_protocol : 8, 461 sk_type : 16; 462 #define SK_PROTOCOL_MAX U8_MAX 463 u16 sk_gso_max_segs; 464 u8 sk_pacing_shift; 465 unsigned long sk_lingertime; 466 struct proto *sk_prot_creator; 467 rwlock_t sk_callback_lock; 468 int sk_err, 469 sk_err_soft; 470 u32 sk_ack_backlog; 471 u32 sk_max_ack_backlog; 472 kuid_t sk_uid; 473 struct pid *sk_peer_pid; 474 const struct cred *sk_peer_cred; 475 long sk_rcvtimeo; 476 ktime_t sk_stamp; 477 #if BITS_PER_LONG==32 478 seqlock_t sk_stamp_seq; 479 #endif 480 u16 sk_tsflags; 481 u8 sk_shutdown; 482 u32 sk_tskey; 483 atomic_t sk_zckey; 484 485 u8 sk_clockid; 486 u8 sk_txtime_deadline_mode : 1, 487 sk_txtime_report_errors : 1, 488 sk_txtime_unused : 6; 489 490 struct socket *sk_socket; 491 void *sk_user_data; 492 #ifdef CONFIG_SECURITY 493 void *sk_security; 494 #endif 495 struct sock_cgroup_data sk_cgrp_data; 496 struct mem_cgroup *sk_memcg; 497 void (*sk_state_change)(struct sock *sk); 498 void (*sk_data_ready)(struct sock *sk); 499 void (*sk_write_space)(struct sock *sk); 500 void (*sk_error_report)(struct sock *sk); 501 int (*sk_backlog_rcv)(struct sock *sk, 502 struct sk_buff *skb); 503 #ifdef CONFIG_SOCK_VALIDATE_XMIT 504 struct sk_buff* (*sk_validate_xmit_skb)(struct sock *sk, 505 struct net_device *dev, 506 struct sk_buff *skb); 507 #endif 508 void (*sk_destruct)(struct sock *sk); 509 struct sock_reuseport __rcu *sk_reuseport_cb; 510 #ifdef CONFIG_BPF_SYSCALL 511 struct bpf_sk_storage __rcu *sk_bpf_storage; 512 #endif 513 struct rcu_head sk_rcu; 514 }; 515 516 enum sk_pacing { 517 SK_PACING_NONE = 0, 518 SK_PACING_NEEDED = 1, 519 SK_PACING_FQ = 2, 520 }; 521 522 #define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data))) 523 524 #define rcu_dereference_sk_user_data(sk) rcu_dereference(__sk_user_data((sk))) 525 #define rcu_assign_sk_user_data(sk, ptr) rcu_assign_pointer(__sk_user_data((sk)), ptr) 526 527 /* 528 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK 529 * or not whether his port will be reused by someone else. SK_FORCE_REUSE 530 * on a socket means that the socket will reuse everybody else's port 531 * without looking at the other's sk_reuse value. 532 */ 533 534 #define SK_NO_REUSE 0 535 #define SK_CAN_REUSE 1 536 #define SK_FORCE_REUSE 2 537 538 int sk_set_peek_off(struct sock *sk, int val); 539 540 static inline int sk_peek_offset(struct sock *sk, int flags) 541 { 542 if (unlikely(flags & MSG_PEEK)) { 543 return READ_ONCE(sk->sk_peek_off); 544 } 545 546 return 0; 547 } 548 549 static inline void sk_peek_offset_bwd(struct sock *sk, int val) 550 { 551 s32 off = READ_ONCE(sk->sk_peek_off); 552 553 if (unlikely(off >= 0)) { 554 off = max_t(s32, off - val, 0); 555 WRITE_ONCE(sk->sk_peek_off, off); 556 } 557 } 558 559 static inline void sk_peek_offset_fwd(struct sock *sk, int val) 560 { 561 sk_peek_offset_bwd(sk, -val); 562 } 563 564 /* 565 * Hashed lists helper routines 566 */ 567 static inline struct sock *sk_entry(const struct hlist_node *node) 568 { 569 return hlist_entry(node, struct sock, sk_node); 570 } 571 572 static inline struct sock *__sk_head(const struct hlist_head *head) 573 { 574 return hlist_entry(head->first, struct sock, sk_node); 575 } 576 577 static inline struct sock *sk_head(const struct hlist_head *head) 578 { 579 return hlist_empty(head) ? NULL : __sk_head(head); 580 } 581 582 static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head) 583 { 584 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node); 585 } 586 587 static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head) 588 { 589 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head); 590 } 591 592 static inline struct sock *sk_next(const struct sock *sk) 593 { 594 return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node); 595 } 596 597 static inline struct sock *sk_nulls_next(const struct sock *sk) 598 { 599 return (!is_a_nulls(sk->sk_nulls_node.next)) ? 600 hlist_nulls_entry(sk->sk_nulls_node.next, 601 struct sock, sk_nulls_node) : 602 NULL; 603 } 604 605 static inline bool sk_unhashed(const struct sock *sk) 606 { 607 return hlist_unhashed(&sk->sk_node); 608 } 609 610 static inline bool sk_hashed(const struct sock *sk) 611 { 612 return !sk_unhashed(sk); 613 } 614 615 static inline void sk_node_init(struct hlist_node *node) 616 { 617 node->pprev = NULL; 618 } 619 620 static inline void sk_nulls_node_init(struct hlist_nulls_node *node) 621 { 622 node->pprev = NULL; 623 } 624 625 static inline void __sk_del_node(struct sock *sk) 626 { 627 __hlist_del(&sk->sk_node); 628 } 629 630 /* NB: equivalent to hlist_del_init_rcu */ 631 static inline bool __sk_del_node_init(struct sock *sk) 632 { 633 if (sk_hashed(sk)) { 634 __sk_del_node(sk); 635 sk_node_init(&sk->sk_node); 636 return true; 637 } 638 return false; 639 } 640 641 /* Grab socket reference count. This operation is valid only 642 when sk is ALREADY grabbed f.e. it is found in hash table 643 or a list and the lookup is made under lock preventing hash table 644 modifications. 645 */ 646 647 static __always_inline void sock_hold(struct sock *sk) 648 { 649 refcount_inc(&sk->sk_refcnt); 650 } 651 652 /* Ungrab socket in the context, which assumes that socket refcnt 653 cannot hit zero, f.e. it is true in context of any socketcall. 654 */ 655 static __always_inline void __sock_put(struct sock *sk) 656 { 657 refcount_dec(&sk->sk_refcnt); 658 } 659 660 static inline bool sk_del_node_init(struct sock *sk) 661 { 662 bool rc = __sk_del_node_init(sk); 663 664 if (rc) { 665 /* paranoid for a while -acme */ 666 WARN_ON(refcount_read(&sk->sk_refcnt) == 1); 667 __sock_put(sk); 668 } 669 return rc; 670 } 671 #define sk_del_node_init_rcu(sk) sk_del_node_init(sk) 672 673 static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk) 674 { 675 if (sk_hashed(sk)) { 676 hlist_nulls_del_init_rcu(&sk->sk_nulls_node); 677 return true; 678 } 679 return false; 680 } 681 682 static inline bool sk_nulls_del_node_init_rcu(struct sock *sk) 683 { 684 bool rc = __sk_nulls_del_node_init_rcu(sk); 685 686 if (rc) { 687 /* paranoid for a while -acme */ 688 WARN_ON(refcount_read(&sk->sk_refcnt) == 1); 689 __sock_put(sk); 690 } 691 return rc; 692 } 693 694 static inline void __sk_add_node(struct sock *sk, struct hlist_head *list) 695 { 696 hlist_add_head(&sk->sk_node, list); 697 } 698 699 static inline void sk_add_node(struct sock *sk, struct hlist_head *list) 700 { 701 sock_hold(sk); 702 __sk_add_node(sk, list); 703 } 704 705 static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list) 706 { 707 sock_hold(sk); 708 if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport && 709 sk->sk_family == AF_INET6) 710 hlist_add_tail_rcu(&sk->sk_node, list); 711 else 712 hlist_add_head_rcu(&sk->sk_node, list); 713 } 714 715 static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list) 716 { 717 sock_hold(sk); 718 hlist_add_tail_rcu(&sk->sk_node, list); 719 } 720 721 static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list) 722 { 723 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list); 724 } 725 726 static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list) 727 { 728 sock_hold(sk); 729 __sk_nulls_add_node_rcu(sk, list); 730 } 731 732 static inline void __sk_del_bind_node(struct sock *sk) 733 { 734 __hlist_del(&sk->sk_bind_node); 735 } 736 737 static inline void sk_add_bind_node(struct sock *sk, 738 struct hlist_head *list) 739 { 740 hlist_add_head(&sk->sk_bind_node, list); 741 } 742 743 #define sk_for_each(__sk, list) \ 744 hlist_for_each_entry(__sk, list, sk_node) 745 #define sk_for_each_rcu(__sk, list) \ 746 hlist_for_each_entry_rcu(__sk, list, sk_node) 747 #define sk_nulls_for_each(__sk, node, list) \ 748 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node) 749 #define sk_nulls_for_each_rcu(__sk, node, list) \ 750 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node) 751 #define sk_for_each_from(__sk) \ 752 hlist_for_each_entry_from(__sk, sk_node) 753 #define sk_nulls_for_each_from(__sk, node) \ 754 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \ 755 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node) 756 #define sk_for_each_safe(__sk, tmp, list) \ 757 hlist_for_each_entry_safe(__sk, tmp, list, sk_node) 758 #define sk_for_each_bound(__sk, list) \ 759 hlist_for_each_entry(__sk, list, sk_bind_node) 760 761 /** 762 * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset 763 * @tpos: the type * to use as a loop cursor. 764 * @pos: the &struct hlist_node to use as a loop cursor. 765 * @head: the head for your list. 766 * @offset: offset of hlist_node within the struct. 767 * 768 */ 769 #define sk_for_each_entry_offset_rcu(tpos, pos, head, offset) \ 770 for (pos = rcu_dereference(hlist_first_rcu(head)); \ 771 pos != NULL && \ 772 ({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \ 773 pos = rcu_dereference(hlist_next_rcu(pos))) 774 775 static inline struct user_namespace *sk_user_ns(struct sock *sk) 776 { 777 /* Careful only use this in a context where these parameters 778 * can not change and must all be valid, such as recvmsg from 779 * userspace. 780 */ 781 return sk->sk_socket->file->f_cred->user_ns; 782 } 783 784 /* Sock flags */ 785 enum sock_flags { 786 SOCK_DEAD, 787 SOCK_DONE, 788 SOCK_URGINLINE, 789 SOCK_KEEPOPEN, 790 SOCK_LINGER, 791 SOCK_DESTROY, 792 SOCK_BROADCAST, 793 SOCK_TIMESTAMP, 794 SOCK_ZAPPED, 795 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */ 796 SOCK_DBG, /* %SO_DEBUG setting */ 797 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */ 798 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */ 799 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */ 800 SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */ 801 SOCK_MEMALLOC, /* VM depends on this socket for swapping */ 802 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */ 803 SOCK_FASYNC, /* fasync() active */ 804 SOCK_RXQ_OVFL, 805 SOCK_ZEROCOPY, /* buffers from userspace */ 806 SOCK_WIFI_STATUS, /* push wifi status to userspace */ 807 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS. 808 * Will use last 4 bytes of packet sent from 809 * user-space instead. 810 */ 811 SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */ 812 SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */ 813 SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */ 814 SOCK_TXTIME, 815 SOCK_XDP, /* XDP is attached */ 816 SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */ 817 }; 818 819 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)) 820 821 static inline void sock_copy_flags(struct sock *nsk, struct sock *osk) 822 { 823 nsk->sk_flags = osk->sk_flags; 824 } 825 826 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag) 827 { 828 __set_bit(flag, &sk->sk_flags); 829 } 830 831 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag) 832 { 833 __clear_bit(flag, &sk->sk_flags); 834 } 835 836 static inline bool sock_flag(const struct sock *sk, enum sock_flags flag) 837 { 838 return test_bit(flag, &sk->sk_flags); 839 } 840 841 #ifdef CONFIG_NET 842 DECLARE_STATIC_KEY_FALSE(memalloc_socks_key); 843 static inline int sk_memalloc_socks(void) 844 { 845 return static_branch_unlikely(&memalloc_socks_key); 846 } 847 #else 848 849 static inline int sk_memalloc_socks(void) 850 { 851 return 0; 852 } 853 854 #endif 855 856 static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask) 857 { 858 return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC); 859 } 860 861 static inline void sk_acceptq_removed(struct sock *sk) 862 { 863 sk->sk_ack_backlog--; 864 } 865 866 static inline void sk_acceptq_added(struct sock *sk) 867 { 868 sk->sk_ack_backlog++; 869 } 870 871 static inline bool sk_acceptq_is_full(const struct sock *sk) 872 { 873 return sk->sk_ack_backlog > sk->sk_max_ack_backlog; 874 } 875 876 /* 877 * Compute minimal free write space needed to queue new packets. 878 */ 879 static inline int sk_stream_min_wspace(const struct sock *sk) 880 { 881 return sk->sk_wmem_queued >> 1; 882 } 883 884 static inline int sk_stream_wspace(const struct sock *sk) 885 { 886 return sk->sk_sndbuf - sk->sk_wmem_queued; 887 } 888 889 void sk_stream_write_space(struct sock *sk); 890 891 /* OOB backlog add */ 892 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb) 893 { 894 /* dont let skb dst not refcounted, we are going to leave rcu lock */ 895 skb_dst_force(skb); 896 897 if (!sk->sk_backlog.tail) 898 sk->sk_backlog.head = skb; 899 else 900 sk->sk_backlog.tail->next = skb; 901 902 sk->sk_backlog.tail = skb; 903 skb->next = NULL; 904 } 905 906 /* 907 * Take into account size of receive queue and backlog queue 908 * Do not take into account this skb truesize, 909 * to allow even a single big packet to come. 910 */ 911 static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit) 912 { 913 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc); 914 915 return qsize > limit; 916 } 917 918 /* The per-socket spinlock must be held here. */ 919 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb, 920 unsigned int limit) 921 { 922 if (sk_rcvqueues_full(sk, limit)) 923 return -ENOBUFS; 924 925 /* 926 * If the skb was allocated from pfmemalloc reserves, only 927 * allow SOCK_MEMALLOC sockets to use it as this socket is 928 * helping free memory 929 */ 930 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) 931 return -ENOMEM; 932 933 __sk_add_backlog(sk, skb); 934 sk->sk_backlog.len += skb->truesize; 935 return 0; 936 } 937 938 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb); 939 940 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 941 { 942 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) 943 return __sk_backlog_rcv(sk, skb); 944 945 return sk->sk_backlog_rcv(sk, skb); 946 } 947 948 static inline void sk_incoming_cpu_update(struct sock *sk) 949 { 950 int cpu = raw_smp_processor_id(); 951 952 if (unlikely(sk->sk_incoming_cpu != cpu)) 953 sk->sk_incoming_cpu = cpu; 954 } 955 956 static inline void sock_rps_record_flow_hash(__u32 hash) 957 { 958 #ifdef CONFIG_RPS 959 struct rps_sock_flow_table *sock_flow_table; 960 961 rcu_read_lock(); 962 sock_flow_table = rcu_dereference(rps_sock_flow_table); 963 rps_record_sock_flow(sock_flow_table, hash); 964 rcu_read_unlock(); 965 #endif 966 } 967 968 static inline void sock_rps_record_flow(const struct sock *sk) 969 { 970 #ifdef CONFIG_RPS 971 if (static_branch_unlikely(&rfs_needed)) { 972 /* Reading sk->sk_rxhash might incur an expensive cache line 973 * miss. 974 * 975 * TCP_ESTABLISHED does cover almost all states where RFS 976 * might be useful, and is cheaper [1] than testing : 977 * IPv4: inet_sk(sk)->inet_daddr 978 * IPv6: ipv6_addr_any(&sk->sk_v6_daddr) 979 * OR an additional socket flag 980 * [1] : sk_state and sk_prot are in the same cache line. 981 */ 982 if (sk->sk_state == TCP_ESTABLISHED) 983 sock_rps_record_flow_hash(sk->sk_rxhash); 984 } 985 #endif 986 } 987 988 static inline void sock_rps_save_rxhash(struct sock *sk, 989 const struct sk_buff *skb) 990 { 991 #ifdef CONFIG_RPS 992 if (unlikely(sk->sk_rxhash != skb->hash)) 993 sk->sk_rxhash = skb->hash; 994 #endif 995 } 996 997 static inline void sock_rps_reset_rxhash(struct sock *sk) 998 { 999 #ifdef CONFIG_RPS 1000 sk->sk_rxhash = 0; 1001 #endif 1002 } 1003 1004 #define sk_wait_event(__sk, __timeo, __condition, __wait) \ 1005 ({ int __rc; \ 1006 release_sock(__sk); \ 1007 __rc = __condition; \ 1008 if (!__rc) { \ 1009 *(__timeo) = wait_woken(__wait, \ 1010 TASK_INTERRUPTIBLE, \ 1011 *(__timeo)); \ 1012 } \ 1013 sched_annotate_sleep(); \ 1014 lock_sock(__sk); \ 1015 __rc = __condition; \ 1016 __rc; \ 1017 }) 1018 1019 int sk_stream_wait_connect(struct sock *sk, long *timeo_p); 1020 int sk_stream_wait_memory(struct sock *sk, long *timeo_p); 1021 void sk_stream_wait_close(struct sock *sk, long timeo_p); 1022 int sk_stream_error(struct sock *sk, int flags, int err); 1023 void sk_stream_kill_queues(struct sock *sk); 1024 void sk_set_memalloc(struct sock *sk); 1025 void sk_clear_memalloc(struct sock *sk); 1026 1027 void __sk_flush_backlog(struct sock *sk); 1028 1029 static inline bool sk_flush_backlog(struct sock *sk) 1030 { 1031 if (unlikely(READ_ONCE(sk->sk_backlog.tail))) { 1032 __sk_flush_backlog(sk); 1033 return true; 1034 } 1035 return false; 1036 } 1037 1038 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb); 1039 1040 struct request_sock_ops; 1041 struct timewait_sock_ops; 1042 struct inet_hashinfo; 1043 struct raw_hashinfo; 1044 struct smc_hashinfo; 1045 struct module; 1046 1047 /* 1048 * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes 1049 * un-modified. Special care is taken when initializing object to zero. 1050 */ 1051 static inline void sk_prot_clear_nulls(struct sock *sk, int size) 1052 { 1053 if (offsetof(struct sock, sk_node.next) != 0) 1054 memset(sk, 0, offsetof(struct sock, sk_node.next)); 1055 memset(&sk->sk_node.pprev, 0, 1056 size - offsetof(struct sock, sk_node.pprev)); 1057 } 1058 1059 /* Networking protocol blocks we attach to sockets. 1060 * socket layer -> transport layer interface 1061 */ 1062 struct proto { 1063 void (*close)(struct sock *sk, 1064 long timeout); 1065 int (*pre_connect)(struct sock *sk, 1066 struct sockaddr *uaddr, 1067 int addr_len); 1068 int (*connect)(struct sock *sk, 1069 struct sockaddr *uaddr, 1070 int addr_len); 1071 int (*disconnect)(struct sock *sk, int flags); 1072 1073 struct sock * (*accept)(struct sock *sk, int flags, int *err, 1074 bool kern); 1075 1076 int (*ioctl)(struct sock *sk, int cmd, 1077 unsigned long arg); 1078 int (*init)(struct sock *sk); 1079 void (*destroy)(struct sock *sk); 1080 void (*shutdown)(struct sock *sk, int how); 1081 int (*setsockopt)(struct sock *sk, int level, 1082 int optname, char __user *optval, 1083 unsigned int optlen); 1084 int (*getsockopt)(struct sock *sk, int level, 1085 int optname, char __user *optval, 1086 int __user *option); 1087 void (*keepalive)(struct sock *sk, int valbool); 1088 #ifdef CONFIG_COMPAT 1089 int (*compat_setsockopt)(struct sock *sk, 1090 int level, 1091 int optname, char __user *optval, 1092 unsigned int optlen); 1093 int (*compat_getsockopt)(struct sock *sk, 1094 int level, 1095 int optname, char __user *optval, 1096 int __user *option); 1097 int (*compat_ioctl)(struct sock *sk, 1098 unsigned int cmd, unsigned long arg); 1099 #endif 1100 int (*sendmsg)(struct sock *sk, struct msghdr *msg, 1101 size_t len); 1102 int (*recvmsg)(struct sock *sk, struct msghdr *msg, 1103 size_t len, int noblock, int flags, 1104 int *addr_len); 1105 int (*sendpage)(struct sock *sk, struct page *page, 1106 int offset, size_t size, int flags); 1107 int (*bind)(struct sock *sk, 1108 struct sockaddr *uaddr, int addr_len); 1109 1110 int (*backlog_rcv) (struct sock *sk, 1111 struct sk_buff *skb); 1112 1113 void (*release_cb)(struct sock *sk); 1114 1115 /* Keeping track of sk's, looking them up, and port selection methods. */ 1116 int (*hash)(struct sock *sk); 1117 void (*unhash)(struct sock *sk); 1118 void (*rehash)(struct sock *sk); 1119 int (*get_port)(struct sock *sk, unsigned short snum); 1120 1121 /* Keeping track of sockets in use */ 1122 #ifdef CONFIG_PROC_FS 1123 unsigned int inuse_idx; 1124 #endif 1125 1126 bool (*stream_memory_free)(const struct sock *sk, int wake); 1127 bool (*stream_memory_read)(const struct sock *sk); 1128 /* Memory pressure */ 1129 void (*enter_memory_pressure)(struct sock *sk); 1130 void (*leave_memory_pressure)(struct sock *sk); 1131 atomic_long_t *memory_allocated; /* Current allocated memory. */ 1132 struct percpu_counter *sockets_allocated; /* Current number of sockets. */ 1133 /* 1134 * Pressure flag: try to collapse. 1135 * Technical note: it is used by multiple contexts non atomically. 1136 * All the __sk_mem_schedule() is of this nature: accounting 1137 * is strict, actions are advisory and have some latency. 1138 */ 1139 unsigned long *memory_pressure; 1140 long *sysctl_mem; 1141 1142 int *sysctl_wmem; 1143 int *sysctl_rmem; 1144 u32 sysctl_wmem_offset; 1145 u32 sysctl_rmem_offset; 1146 1147 int max_header; 1148 bool no_autobind; 1149 1150 struct kmem_cache *slab; 1151 unsigned int obj_size; 1152 slab_flags_t slab_flags; 1153 unsigned int useroffset; /* Usercopy region offset */ 1154 unsigned int usersize; /* Usercopy region size */ 1155 1156 struct percpu_counter *orphan_count; 1157 1158 struct request_sock_ops *rsk_prot; 1159 struct timewait_sock_ops *twsk_prot; 1160 1161 union { 1162 struct inet_hashinfo *hashinfo; 1163 struct udp_table *udp_table; 1164 struct raw_hashinfo *raw_hash; 1165 struct smc_hashinfo *smc_hash; 1166 } h; 1167 1168 struct module *owner; 1169 1170 char name[32]; 1171 1172 struct list_head node; 1173 #ifdef SOCK_REFCNT_DEBUG 1174 atomic_t socks; 1175 #endif 1176 int (*diag_destroy)(struct sock *sk, int err); 1177 } __randomize_layout; 1178 1179 int proto_register(struct proto *prot, int alloc_slab); 1180 void proto_unregister(struct proto *prot); 1181 int sock_load_diag_module(int family, int protocol); 1182 1183 #ifdef SOCK_REFCNT_DEBUG 1184 static inline void sk_refcnt_debug_inc(struct sock *sk) 1185 { 1186 atomic_inc(&sk->sk_prot->socks); 1187 } 1188 1189 static inline void sk_refcnt_debug_dec(struct sock *sk) 1190 { 1191 atomic_dec(&sk->sk_prot->socks); 1192 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n", 1193 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks)); 1194 } 1195 1196 static inline void sk_refcnt_debug_release(const struct sock *sk) 1197 { 1198 if (refcount_read(&sk->sk_refcnt) != 1) 1199 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n", 1200 sk->sk_prot->name, sk, refcount_read(&sk->sk_refcnt)); 1201 } 1202 #else /* SOCK_REFCNT_DEBUG */ 1203 #define sk_refcnt_debug_inc(sk) do { } while (0) 1204 #define sk_refcnt_debug_dec(sk) do { } while (0) 1205 #define sk_refcnt_debug_release(sk) do { } while (0) 1206 #endif /* SOCK_REFCNT_DEBUG */ 1207 1208 static inline bool __sk_stream_memory_free(const struct sock *sk, int wake) 1209 { 1210 if (sk->sk_wmem_queued >= sk->sk_sndbuf) 1211 return false; 1212 1213 return sk->sk_prot->stream_memory_free ? 1214 sk->sk_prot->stream_memory_free(sk, wake) : true; 1215 } 1216 1217 static inline bool sk_stream_memory_free(const struct sock *sk) 1218 { 1219 return __sk_stream_memory_free(sk, 0); 1220 } 1221 1222 static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake) 1223 { 1224 return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) && 1225 __sk_stream_memory_free(sk, wake); 1226 } 1227 1228 static inline bool sk_stream_is_writeable(const struct sock *sk) 1229 { 1230 return __sk_stream_is_writeable(sk, 0); 1231 } 1232 1233 static inline int sk_under_cgroup_hierarchy(struct sock *sk, 1234 struct cgroup *ancestor) 1235 { 1236 #ifdef CONFIG_SOCK_CGROUP_DATA 1237 return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data), 1238 ancestor); 1239 #else 1240 return -ENOTSUPP; 1241 #endif 1242 } 1243 1244 static inline bool sk_has_memory_pressure(const struct sock *sk) 1245 { 1246 return sk->sk_prot->memory_pressure != NULL; 1247 } 1248 1249 static inline bool sk_under_memory_pressure(const struct sock *sk) 1250 { 1251 if (!sk->sk_prot->memory_pressure) 1252 return false; 1253 1254 if (mem_cgroup_sockets_enabled && sk->sk_memcg && 1255 mem_cgroup_under_socket_pressure(sk->sk_memcg)) 1256 return true; 1257 1258 return !!*sk->sk_prot->memory_pressure; 1259 } 1260 1261 static inline long 1262 sk_memory_allocated(const struct sock *sk) 1263 { 1264 return atomic_long_read(sk->sk_prot->memory_allocated); 1265 } 1266 1267 static inline long 1268 sk_memory_allocated_add(struct sock *sk, int amt) 1269 { 1270 return atomic_long_add_return(amt, sk->sk_prot->memory_allocated); 1271 } 1272 1273 static inline void 1274 sk_memory_allocated_sub(struct sock *sk, int amt) 1275 { 1276 atomic_long_sub(amt, sk->sk_prot->memory_allocated); 1277 } 1278 1279 static inline void sk_sockets_allocated_dec(struct sock *sk) 1280 { 1281 percpu_counter_dec(sk->sk_prot->sockets_allocated); 1282 } 1283 1284 static inline void sk_sockets_allocated_inc(struct sock *sk) 1285 { 1286 percpu_counter_inc(sk->sk_prot->sockets_allocated); 1287 } 1288 1289 static inline u64 1290 sk_sockets_allocated_read_positive(struct sock *sk) 1291 { 1292 return percpu_counter_read_positive(sk->sk_prot->sockets_allocated); 1293 } 1294 1295 static inline int 1296 proto_sockets_allocated_sum_positive(struct proto *prot) 1297 { 1298 return percpu_counter_sum_positive(prot->sockets_allocated); 1299 } 1300 1301 static inline long 1302 proto_memory_allocated(struct proto *prot) 1303 { 1304 return atomic_long_read(prot->memory_allocated); 1305 } 1306 1307 static inline bool 1308 proto_memory_pressure(struct proto *prot) 1309 { 1310 if (!prot->memory_pressure) 1311 return false; 1312 return !!*prot->memory_pressure; 1313 } 1314 1315 1316 #ifdef CONFIG_PROC_FS 1317 /* Called with local bh disabled */ 1318 void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc); 1319 int sock_prot_inuse_get(struct net *net, struct proto *proto); 1320 int sock_inuse_get(struct net *net); 1321 #else 1322 static inline void sock_prot_inuse_add(struct net *net, struct proto *prot, 1323 int inc) 1324 { 1325 } 1326 #endif 1327 1328 1329 /* With per-bucket locks this operation is not-atomic, so that 1330 * this version is not worse. 1331 */ 1332 static inline int __sk_prot_rehash(struct sock *sk) 1333 { 1334 sk->sk_prot->unhash(sk); 1335 return sk->sk_prot->hash(sk); 1336 } 1337 1338 /* About 10 seconds */ 1339 #define SOCK_DESTROY_TIME (10*HZ) 1340 1341 /* Sockets 0-1023 can't be bound to unless you are superuser */ 1342 #define PROT_SOCK 1024 1343 1344 #define SHUTDOWN_MASK 3 1345 #define RCV_SHUTDOWN 1 1346 #define SEND_SHUTDOWN 2 1347 1348 #define SOCK_SNDBUF_LOCK 1 1349 #define SOCK_RCVBUF_LOCK 2 1350 #define SOCK_BINDADDR_LOCK 4 1351 #define SOCK_BINDPORT_LOCK 8 1352 1353 struct socket_alloc { 1354 struct socket socket; 1355 struct inode vfs_inode; 1356 }; 1357 1358 static inline struct socket *SOCKET_I(struct inode *inode) 1359 { 1360 return &container_of(inode, struct socket_alloc, vfs_inode)->socket; 1361 } 1362 1363 static inline struct inode *SOCK_INODE(struct socket *socket) 1364 { 1365 return &container_of(socket, struct socket_alloc, socket)->vfs_inode; 1366 } 1367 1368 /* 1369 * Functions for memory accounting 1370 */ 1371 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind); 1372 int __sk_mem_schedule(struct sock *sk, int size, int kind); 1373 void __sk_mem_reduce_allocated(struct sock *sk, int amount); 1374 void __sk_mem_reclaim(struct sock *sk, int amount); 1375 1376 /* We used to have PAGE_SIZE here, but systems with 64KB pages 1377 * do not necessarily have 16x time more memory than 4KB ones. 1378 */ 1379 #define SK_MEM_QUANTUM 4096 1380 #define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM) 1381 #define SK_MEM_SEND 0 1382 #define SK_MEM_RECV 1 1383 1384 /* sysctl_mem values are in pages, we convert them in SK_MEM_QUANTUM units */ 1385 static inline long sk_prot_mem_limits(const struct sock *sk, int index) 1386 { 1387 long val = sk->sk_prot->sysctl_mem[index]; 1388 1389 #if PAGE_SIZE > SK_MEM_QUANTUM 1390 val <<= PAGE_SHIFT - SK_MEM_QUANTUM_SHIFT; 1391 #elif PAGE_SIZE < SK_MEM_QUANTUM 1392 val >>= SK_MEM_QUANTUM_SHIFT - PAGE_SHIFT; 1393 #endif 1394 return val; 1395 } 1396 1397 static inline int sk_mem_pages(int amt) 1398 { 1399 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT; 1400 } 1401 1402 static inline bool sk_has_account(struct sock *sk) 1403 { 1404 /* return true if protocol supports memory accounting */ 1405 return !!sk->sk_prot->memory_allocated; 1406 } 1407 1408 static inline bool sk_wmem_schedule(struct sock *sk, int size) 1409 { 1410 if (!sk_has_account(sk)) 1411 return true; 1412 return size <= sk->sk_forward_alloc || 1413 __sk_mem_schedule(sk, size, SK_MEM_SEND); 1414 } 1415 1416 static inline bool 1417 sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size) 1418 { 1419 if (!sk_has_account(sk)) 1420 return true; 1421 return size<= sk->sk_forward_alloc || 1422 __sk_mem_schedule(sk, size, SK_MEM_RECV) || 1423 skb_pfmemalloc(skb); 1424 } 1425 1426 static inline void sk_mem_reclaim(struct sock *sk) 1427 { 1428 if (!sk_has_account(sk)) 1429 return; 1430 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM) 1431 __sk_mem_reclaim(sk, sk->sk_forward_alloc); 1432 } 1433 1434 static inline void sk_mem_reclaim_partial(struct sock *sk) 1435 { 1436 if (!sk_has_account(sk)) 1437 return; 1438 if (sk->sk_forward_alloc > SK_MEM_QUANTUM) 1439 __sk_mem_reclaim(sk, sk->sk_forward_alloc - 1); 1440 } 1441 1442 static inline void sk_mem_charge(struct sock *sk, int size) 1443 { 1444 if (!sk_has_account(sk)) 1445 return; 1446 sk->sk_forward_alloc -= size; 1447 } 1448 1449 static inline void sk_mem_uncharge(struct sock *sk, int size) 1450 { 1451 if (!sk_has_account(sk)) 1452 return; 1453 sk->sk_forward_alloc += size; 1454 1455 /* Avoid a possible overflow. 1456 * TCP send queues can make this happen, if sk_mem_reclaim() 1457 * is not called and more than 2 GBytes are released at once. 1458 * 1459 * If we reach 2 MBytes, reclaim 1 MBytes right now, there is 1460 * no need to hold that much forward allocation anyway. 1461 */ 1462 if (unlikely(sk->sk_forward_alloc >= 1 << 21)) 1463 __sk_mem_reclaim(sk, 1 << 20); 1464 } 1465 1466 static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb) 1467 { 1468 sock_set_flag(sk, SOCK_QUEUE_SHRUNK); 1469 sk->sk_wmem_queued -= skb->truesize; 1470 sk_mem_uncharge(sk, skb->truesize); 1471 if (!sk->sk_tx_skb_cache && !skb_cloned(skb)) { 1472 skb_zcopy_clear(skb, true); 1473 sk->sk_tx_skb_cache = skb; 1474 return; 1475 } 1476 __kfree_skb(skb); 1477 } 1478 1479 static inline void sock_release_ownership(struct sock *sk) 1480 { 1481 if (sk->sk_lock.owned) { 1482 sk->sk_lock.owned = 0; 1483 1484 /* The sk_lock has mutex_unlock() semantics: */ 1485 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); 1486 } 1487 } 1488 1489 /* 1490 * Macro so as to not evaluate some arguments when 1491 * lockdep is not enabled. 1492 * 1493 * Mark both the sk_lock and the sk_lock.slock as a 1494 * per-address-family lock class. 1495 */ 1496 #define sock_lock_init_class_and_name(sk, sname, skey, name, key) \ 1497 do { \ 1498 sk->sk_lock.owned = 0; \ 1499 init_waitqueue_head(&sk->sk_lock.wq); \ 1500 spin_lock_init(&(sk)->sk_lock.slock); \ 1501 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \ 1502 sizeof((sk)->sk_lock)); \ 1503 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \ 1504 (skey), (sname)); \ 1505 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \ 1506 } while (0) 1507 1508 #ifdef CONFIG_LOCKDEP 1509 static inline bool lockdep_sock_is_held(const struct sock *sk) 1510 { 1511 return lockdep_is_held(&sk->sk_lock) || 1512 lockdep_is_held(&sk->sk_lock.slock); 1513 } 1514 #endif 1515 1516 void lock_sock_nested(struct sock *sk, int subclass); 1517 1518 static inline void lock_sock(struct sock *sk) 1519 { 1520 lock_sock_nested(sk, 0); 1521 } 1522 1523 void __release_sock(struct sock *sk); 1524 void release_sock(struct sock *sk); 1525 1526 /* BH context may only use the following locking interface. */ 1527 #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock)) 1528 #define bh_lock_sock_nested(__sk) \ 1529 spin_lock_nested(&((__sk)->sk_lock.slock), \ 1530 SINGLE_DEPTH_NESTING) 1531 #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock)) 1532 1533 bool lock_sock_fast(struct sock *sk); 1534 /** 1535 * unlock_sock_fast - complement of lock_sock_fast 1536 * @sk: socket 1537 * @slow: slow mode 1538 * 1539 * fast unlock socket for user context. 1540 * If slow mode is on, we call regular release_sock() 1541 */ 1542 static inline void unlock_sock_fast(struct sock *sk, bool slow) 1543 { 1544 if (slow) 1545 release_sock(sk); 1546 else 1547 spin_unlock_bh(&sk->sk_lock.slock); 1548 } 1549 1550 /* Used by processes to "lock" a socket state, so that 1551 * interrupts and bottom half handlers won't change it 1552 * from under us. It essentially blocks any incoming 1553 * packets, so that we won't get any new data or any 1554 * packets that change the state of the socket. 1555 * 1556 * While locked, BH processing will add new packets to 1557 * the backlog queue. This queue is processed by the 1558 * owner of the socket lock right before it is released. 1559 * 1560 * Since ~2.3.5 it is also exclusive sleep lock serializing 1561 * accesses from user process context. 1562 */ 1563 1564 static inline void sock_owned_by_me(const struct sock *sk) 1565 { 1566 #ifdef CONFIG_LOCKDEP 1567 WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks); 1568 #endif 1569 } 1570 1571 static inline bool sock_owned_by_user(const struct sock *sk) 1572 { 1573 sock_owned_by_me(sk); 1574 return sk->sk_lock.owned; 1575 } 1576 1577 static inline bool sock_owned_by_user_nocheck(const struct sock *sk) 1578 { 1579 return sk->sk_lock.owned; 1580 } 1581 1582 /* no reclassification while locks are held */ 1583 static inline bool sock_allow_reclassification(const struct sock *csk) 1584 { 1585 struct sock *sk = (struct sock *)csk; 1586 1587 return !sk->sk_lock.owned && !spin_is_locked(&sk->sk_lock.slock); 1588 } 1589 1590 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 1591 struct proto *prot, int kern); 1592 void sk_free(struct sock *sk); 1593 void sk_destruct(struct sock *sk); 1594 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority); 1595 void sk_free_unlock_clone(struct sock *sk); 1596 1597 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 1598 gfp_t priority); 1599 void __sock_wfree(struct sk_buff *skb); 1600 void sock_wfree(struct sk_buff *skb); 1601 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size, 1602 gfp_t priority); 1603 void skb_orphan_partial(struct sk_buff *skb); 1604 void sock_rfree(struct sk_buff *skb); 1605 void sock_efree(struct sk_buff *skb); 1606 #ifdef CONFIG_INET 1607 void sock_edemux(struct sk_buff *skb); 1608 #else 1609 #define sock_edemux sock_efree 1610 #endif 1611 1612 int sock_setsockopt(struct socket *sock, int level, int op, 1613 char __user *optval, unsigned int optlen); 1614 1615 int sock_getsockopt(struct socket *sock, int level, int op, 1616 char __user *optval, int __user *optlen); 1617 int sock_gettstamp(struct socket *sock, void __user *userstamp, 1618 bool timeval, bool time32); 1619 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, 1620 int noblock, int *errcode); 1621 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 1622 unsigned long data_len, int noblock, 1623 int *errcode, int max_page_order); 1624 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority); 1625 void sock_kfree_s(struct sock *sk, void *mem, int size); 1626 void sock_kzfree_s(struct sock *sk, void *mem, int size); 1627 void sk_send_sigurg(struct sock *sk); 1628 1629 struct sockcm_cookie { 1630 u64 transmit_time; 1631 u32 mark; 1632 u16 tsflags; 1633 }; 1634 1635 static inline void sockcm_init(struct sockcm_cookie *sockc, 1636 const struct sock *sk) 1637 { 1638 *sockc = (struct sockcm_cookie) { .tsflags = sk->sk_tsflags }; 1639 } 1640 1641 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg, 1642 struct sockcm_cookie *sockc); 1643 int sock_cmsg_send(struct sock *sk, struct msghdr *msg, 1644 struct sockcm_cookie *sockc); 1645 1646 /* 1647 * Functions to fill in entries in struct proto_ops when a protocol 1648 * does not implement a particular function. 1649 */ 1650 int sock_no_bind(struct socket *, struct sockaddr *, int); 1651 int sock_no_connect(struct socket *, struct sockaddr *, int, int); 1652 int sock_no_socketpair(struct socket *, struct socket *); 1653 int sock_no_accept(struct socket *, struct socket *, int, bool); 1654 int sock_no_getname(struct socket *, struct sockaddr *, int); 1655 int sock_no_ioctl(struct socket *, unsigned int, unsigned long); 1656 int sock_no_listen(struct socket *, int); 1657 int sock_no_shutdown(struct socket *, int); 1658 int sock_no_getsockopt(struct socket *, int , int, char __user *, int __user *); 1659 int sock_no_setsockopt(struct socket *, int, int, char __user *, unsigned int); 1660 int sock_no_sendmsg(struct socket *, struct msghdr *, size_t); 1661 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len); 1662 int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int); 1663 int sock_no_mmap(struct file *file, struct socket *sock, 1664 struct vm_area_struct *vma); 1665 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, 1666 size_t size, int flags); 1667 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page, 1668 int offset, size_t size, int flags); 1669 1670 /* 1671 * Functions to fill in entries in struct proto_ops when a protocol 1672 * uses the inet style. 1673 */ 1674 int sock_common_getsockopt(struct socket *sock, int level, int optname, 1675 char __user *optval, int __user *optlen); 1676 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 1677 int flags); 1678 int sock_common_setsockopt(struct socket *sock, int level, int optname, 1679 char __user *optval, unsigned int optlen); 1680 int compat_sock_common_getsockopt(struct socket *sock, int level, 1681 int optname, char __user *optval, int __user *optlen); 1682 int compat_sock_common_setsockopt(struct socket *sock, int level, 1683 int optname, char __user *optval, unsigned int optlen); 1684 1685 void sk_common_release(struct sock *sk); 1686 1687 /* 1688 * Default socket callbacks and setup code 1689 */ 1690 1691 /* Initialise core socket variables */ 1692 void sock_init_data(struct socket *sock, struct sock *sk); 1693 1694 /* 1695 * Socket reference counting postulates. 1696 * 1697 * * Each user of socket SHOULD hold a reference count. 1698 * * Each access point to socket (an hash table bucket, reference from a list, 1699 * running timer, skb in flight MUST hold a reference count. 1700 * * When reference count hits 0, it means it will never increase back. 1701 * * When reference count hits 0, it means that no references from 1702 * outside exist to this socket and current process on current CPU 1703 * is last user and may/should destroy this socket. 1704 * * sk_free is called from any context: process, BH, IRQ. When 1705 * it is called, socket has no references from outside -> sk_free 1706 * may release descendant resources allocated by the socket, but 1707 * to the time when it is called, socket is NOT referenced by any 1708 * hash tables, lists etc. 1709 * * Packets, delivered from outside (from network or from another process) 1710 * and enqueued on receive/error queues SHOULD NOT grab reference count, 1711 * when they sit in queue. Otherwise, packets will leak to hole, when 1712 * socket is looked up by one cpu and unhasing is made by another CPU. 1713 * It is true for udp/raw, netlink (leak to receive and error queues), tcp 1714 * (leak to backlog). Packet socket does all the processing inside 1715 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets 1716 * use separate SMP lock, so that they are prone too. 1717 */ 1718 1719 /* Ungrab socket and destroy it, if it was the last reference. */ 1720 static inline void sock_put(struct sock *sk) 1721 { 1722 if (refcount_dec_and_test(&sk->sk_refcnt)) 1723 sk_free(sk); 1724 } 1725 /* Generic version of sock_put(), dealing with all sockets 1726 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...) 1727 */ 1728 void sock_gen_put(struct sock *sk); 1729 1730 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested, 1731 unsigned int trim_cap, bool refcounted); 1732 static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb, 1733 const int nested) 1734 { 1735 return __sk_receive_skb(sk, skb, nested, 1, true); 1736 } 1737 1738 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue) 1739 { 1740 /* sk_tx_queue_mapping accept only upto a 16-bit value */ 1741 if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX)) 1742 return; 1743 sk->sk_tx_queue_mapping = tx_queue; 1744 } 1745 1746 #define NO_QUEUE_MAPPING USHRT_MAX 1747 1748 static inline void sk_tx_queue_clear(struct sock *sk) 1749 { 1750 sk->sk_tx_queue_mapping = NO_QUEUE_MAPPING; 1751 } 1752 1753 static inline int sk_tx_queue_get(const struct sock *sk) 1754 { 1755 if (sk && sk->sk_tx_queue_mapping != NO_QUEUE_MAPPING) 1756 return sk->sk_tx_queue_mapping; 1757 1758 return -1; 1759 } 1760 1761 static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb) 1762 { 1763 #ifdef CONFIG_XPS 1764 if (skb_rx_queue_recorded(skb)) { 1765 u16 rx_queue = skb_get_rx_queue(skb); 1766 1767 if (WARN_ON_ONCE(rx_queue == NO_QUEUE_MAPPING)) 1768 return; 1769 1770 sk->sk_rx_queue_mapping = rx_queue; 1771 } 1772 #endif 1773 } 1774 1775 static inline void sk_rx_queue_clear(struct sock *sk) 1776 { 1777 #ifdef CONFIG_XPS 1778 sk->sk_rx_queue_mapping = NO_QUEUE_MAPPING; 1779 #endif 1780 } 1781 1782 #ifdef CONFIG_XPS 1783 static inline int sk_rx_queue_get(const struct sock *sk) 1784 { 1785 if (sk && sk->sk_rx_queue_mapping != NO_QUEUE_MAPPING) 1786 return sk->sk_rx_queue_mapping; 1787 1788 return -1; 1789 } 1790 #endif 1791 1792 static inline void sk_set_socket(struct sock *sk, struct socket *sock) 1793 { 1794 sk_tx_queue_clear(sk); 1795 sk->sk_socket = sock; 1796 } 1797 1798 static inline wait_queue_head_t *sk_sleep(struct sock *sk) 1799 { 1800 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0); 1801 return &rcu_dereference_raw(sk->sk_wq)->wait; 1802 } 1803 /* Detach socket from process context. 1804 * Announce socket dead, detach it from wait queue and inode. 1805 * Note that parent inode held reference count on this struct sock, 1806 * we do not release it in this function, because protocol 1807 * probably wants some additional cleanups or even continuing 1808 * to work with this socket (TCP). 1809 */ 1810 static inline void sock_orphan(struct sock *sk) 1811 { 1812 write_lock_bh(&sk->sk_callback_lock); 1813 sock_set_flag(sk, SOCK_DEAD); 1814 sk_set_socket(sk, NULL); 1815 sk->sk_wq = NULL; 1816 write_unlock_bh(&sk->sk_callback_lock); 1817 } 1818 1819 static inline void sock_graft(struct sock *sk, struct socket *parent) 1820 { 1821 WARN_ON(parent->sk); 1822 write_lock_bh(&sk->sk_callback_lock); 1823 rcu_assign_pointer(sk->sk_wq, parent->wq); 1824 parent->sk = sk; 1825 sk_set_socket(sk, parent); 1826 sk->sk_uid = SOCK_INODE(parent)->i_uid; 1827 security_sock_graft(sk, parent); 1828 write_unlock_bh(&sk->sk_callback_lock); 1829 } 1830 1831 kuid_t sock_i_uid(struct sock *sk); 1832 unsigned long sock_i_ino(struct sock *sk); 1833 1834 static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk) 1835 { 1836 return sk ? sk->sk_uid : make_kuid(net->user_ns, 0); 1837 } 1838 1839 static inline u32 net_tx_rndhash(void) 1840 { 1841 u32 v = prandom_u32(); 1842 1843 return v ?: 1; 1844 } 1845 1846 static inline void sk_set_txhash(struct sock *sk) 1847 { 1848 sk->sk_txhash = net_tx_rndhash(); 1849 } 1850 1851 static inline void sk_rethink_txhash(struct sock *sk) 1852 { 1853 if (sk->sk_txhash) 1854 sk_set_txhash(sk); 1855 } 1856 1857 static inline struct dst_entry * 1858 __sk_dst_get(struct sock *sk) 1859 { 1860 return rcu_dereference_check(sk->sk_dst_cache, 1861 lockdep_sock_is_held(sk)); 1862 } 1863 1864 static inline struct dst_entry * 1865 sk_dst_get(struct sock *sk) 1866 { 1867 struct dst_entry *dst; 1868 1869 rcu_read_lock(); 1870 dst = rcu_dereference(sk->sk_dst_cache); 1871 if (dst && !atomic_inc_not_zero(&dst->__refcnt)) 1872 dst = NULL; 1873 rcu_read_unlock(); 1874 return dst; 1875 } 1876 1877 static inline void dst_negative_advice(struct sock *sk) 1878 { 1879 struct dst_entry *ndst, *dst = __sk_dst_get(sk); 1880 1881 sk_rethink_txhash(sk); 1882 1883 if (dst && dst->ops->negative_advice) { 1884 ndst = dst->ops->negative_advice(dst); 1885 1886 if (ndst != dst) { 1887 rcu_assign_pointer(sk->sk_dst_cache, ndst); 1888 sk_tx_queue_clear(sk); 1889 sk->sk_dst_pending_confirm = 0; 1890 } 1891 } 1892 } 1893 1894 static inline void 1895 __sk_dst_set(struct sock *sk, struct dst_entry *dst) 1896 { 1897 struct dst_entry *old_dst; 1898 1899 sk_tx_queue_clear(sk); 1900 sk->sk_dst_pending_confirm = 0; 1901 old_dst = rcu_dereference_protected(sk->sk_dst_cache, 1902 lockdep_sock_is_held(sk)); 1903 rcu_assign_pointer(sk->sk_dst_cache, dst); 1904 dst_release(old_dst); 1905 } 1906 1907 static inline void 1908 sk_dst_set(struct sock *sk, struct dst_entry *dst) 1909 { 1910 struct dst_entry *old_dst; 1911 1912 sk_tx_queue_clear(sk); 1913 sk->sk_dst_pending_confirm = 0; 1914 old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst); 1915 dst_release(old_dst); 1916 } 1917 1918 static inline void 1919 __sk_dst_reset(struct sock *sk) 1920 { 1921 __sk_dst_set(sk, NULL); 1922 } 1923 1924 static inline void 1925 sk_dst_reset(struct sock *sk) 1926 { 1927 sk_dst_set(sk, NULL); 1928 } 1929 1930 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie); 1931 1932 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie); 1933 1934 static inline void sk_dst_confirm(struct sock *sk) 1935 { 1936 if (!sk->sk_dst_pending_confirm) 1937 sk->sk_dst_pending_confirm = 1; 1938 } 1939 1940 static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n) 1941 { 1942 if (skb_get_dst_pending_confirm(skb)) { 1943 struct sock *sk = skb->sk; 1944 unsigned long now = jiffies; 1945 1946 /* avoid dirtying neighbour */ 1947 if (n->confirmed != now) 1948 n->confirmed = now; 1949 if (sk && sk->sk_dst_pending_confirm) 1950 sk->sk_dst_pending_confirm = 0; 1951 } 1952 } 1953 1954 bool sk_mc_loop(struct sock *sk); 1955 1956 static inline bool sk_can_gso(const struct sock *sk) 1957 { 1958 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type); 1959 } 1960 1961 void sk_setup_caps(struct sock *sk, struct dst_entry *dst); 1962 1963 static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags) 1964 { 1965 sk->sk_route_nocaps |= flags; 1966 sk->sk_route_caps &= ~flags; 1967 } 1968 1969 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb, 1970 struct iov_iter *from, char *to, 1971 int copy, int offset) 1972 { 1973 if (skb->ip_summed == CHECKSUM_NONE) { 1974 __wsum csum = 0; 1975 if (!csum_and_copy_from_iter_full(to, copy, &csum, from)) 1976 return -EFAULT; 1977 skb->csum = csum_block_add(skb->csum, csum, offset); 1978 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) { 1979 if (!copy_from_iter_full_nocache(to, copy, from)) 1980 return -EFAULT; 1981 } else if (!copy_from_iter_full(to, copy, from)) 1982 return -EFAULT; 1983 1984 return 0; 1985 } 1986 1987 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb, 1988 struct iov_iter *from, int copy) 1989 { 1990 int err, offset = skb->len; 1991 1992 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy), 1993 copy, offset); 1994 if (err) 1995 __skb_trim(skb, offset); 1996 1997 return err; 1998 } 1999 2000 static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from, 2001 struct sk_buff *skb, 2002 struct page *page, 2003 int off, int copy) 2004 { 2005 int err; 2006 2007 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off, 2008 copy, skb->len); 2009 if (err) 2010 return err; 2011 2012 skb->len += copy; 2013 skb->data_len += copy; 2014 skb->truesize += copy; 2015 sk->sk_wmem_queued += copy; 2016 sk_mem_charge(sk, copy); 2017 return 0; 2018 } 2019 2020 /** 2021 * sk_wmem_alloc_get - returns write allocations 2022 * @sk: socket 2023 * 2024 * Returns sk_wmem_alloc minus initial offset of one 2025 */ 2026 static inline int sk_wmem_alloc_get(const struct sock *sk) 2027 { 2028 return refcount_read(&sk->sk_wmem_alloc) - 1; 2029 } 2030 2031 /** 2032 * sk_rmem_alloc_get - returns read allocations 2033 * @sk: socket 2034 * 2035 * Returns sk_rmem_alloc 2036 */ 2037 static inline int sk_rmem_alloc_get(const struct sock *sk) 2038 { 2039 return atomic_read(&sk->sk_rmem_alloc); 2040 } 2041 2042 /** 2043 * sk_has_allocations - check if allocations are outstanding 2044 * @sk: socket 2045 * 2046 * Returns true if socket has write or read allocations 2047 */ 2048 static inline bool sk_has_allocations(const struct sock *sk) 2049 { 2050 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk); 2051 } 2052 2053 /** 2054 * skwq_has_sleeper - check if there are any waiting processes 2055 * @wq: struct socket_wq 2056 * 2057 * Returns true if socket_wq has waiting processes 2058 * 2059 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory 2060 * barrier call. They were added due to the race found within the tcp code. 2061 * 2062 * Consider following tcp code paths:: 2063 * 2064 * CPU1 CPU2 2065 * sys_select receive packet 2066 * ... ... 2067 * __add_wait_queue update tp->rcv_nxt 2068 * ... ... 2069 * tp->rcv_nxt check sock_def_readable 2070 * ... { 2071 * schedule rcu_read_lock(); 2072 * wq = rcu_dereference(sk->sk_wq); 2073 * if (wq && waitqueue_active(&wq->wait)) 2074 * wake_up_interruptible(&wq->wait) 2075 * ... 2076 * } 2077 * 2078 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay 2079 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1 2080 * could then endup calling schedule and sleep forever if there are no more 2081 * data on the socket. 2082 * 2083 */ 2084 static inline bool skwq_has_sleeper(struct socket_wq *wq) 2085 { 2086 return wq && wq_has_sleeper(&wq->wait); 2087 } 2088 2089 /** 2090 * sock_poll_wait - place memory barrier behind the poll_wait call. 2091 * @filp: file 2092 * @sock: socket to wait on 2093 * @p: poll_table 2094 * 2095 * See the comments in the wq_has_sleeper function. 2096 */ 2097 static inline void sock_poll_wait(struct file *filp, struct socket *sock, 2098 poll_table *p) 2099 { 2100 if (!poll_does_not_wait(p)) { 2101 poll_wait(filp, &sock->wq->wait, p); 2102 /* We need to be sure we are in sync with the 2103 * socket flags modification. 2104 * 2105 * This memory barrier is paired in the wq_has_sleeper. 2106 */ 2107 smp_mb(); 2108 } 2109 } 2110 2111 static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk) 2112 { 2113 if (sk->sk_txhash) { 2114 skb->l4_hash = 1; 2115 skb->hash = sk->sk_txhash; 2116 } 2117 } 2118 2119 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk); 2120 2121 /* 2122 * Queue a received datagram if it will fit. Stream and sequenced 2123 * protocols can't normally use this as they need to fit buffers in 2124 * and play with them. 2125 * 2126 * Inlined as it's very short and called for pretty much every 2127 * packet ever received. 2128 */ 2129 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk) 2130 { 2131 skb_orphan(skb); 2132 skb->sk = sk; 2133 skb->destructor = sock_rfree; 2134 atomic_add(skb->truesize, &sk->sk_rmem_alloc); 2135 sk_mem_charge(sk, skb->truesize); 2136 } 2137 2138 void sk_reset_timer(struct sock *sk, struct timer_list *timer, 2139 unsigned long expires); 2140 2141 void sk_stop_timer(struct sock *sk, struct timer_list *timer); 2142 2143 int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue, 2144 struct sk_buff *skb, unsigned int flags, 2145 void (*destructor)(struct sock *sk, 2146 struct sk_buff *skb)); 2147 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); 2148 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); 2149 2150 int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb); 2151 struct sk_buff *sock_dequeue_err_skb(struct sock *sk); 2152 2153 /* 2154 * Recover an error report and clear atomically 2155 */ 2156 2157 static inline int sock_error(struct sock *sk) 2158 { 2159 int err; 2160 if (likely(!sk->sk_err)) 2161 return 0; 2162 err = xchg(&sk->sk_err, 0); 2163 return -err; 2164 } 2165 2166 static inline unsigned long sock_wspace(struct sock *sk) 2167 { 2168 int amt = 0; 2169 2170 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { 2171 amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc); 2172 if (amt < 0) 2173 amt = 0; 2174 } 2175 return amt; 2176 } 2177 2178 /* Note: 2179 * We use sk->sk_wq_raw, from contexts knowing this 2180 * pointer is not NULL and cannot disappear/change. 2181 */ 2182 static inline void sk_set_bit(int nr, struct sock *sk) 2183 { 2184 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) && 2185 !sock_flag(sk, SOCK_FASYNC)) 2186 return; 2187 2188 set_bit(nr, &sk->sk_wq_raw->flags); 2189 } 2190 2191 static inline void sk_clear_bit(int nr, struct sock *sk) 2192 { 2193 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) && 2194 !sock_flag(sk, SOCK_FASYNC)) 2195 return; 2196 2197 clear_bit(nr, &sk->sk_wq_raw->flags); 2198 } 2199 2200 static inline void sk_wake_async(const struct sock *sk, int how, int band) 2201 { 2202 if (sock_flag(sk, SOCK_FASYNC)) { 2203 rcu_read_lock(); 2204 sock_wake_async(rcu_dereference(sk->sk_wq), how, band); 2205 rcu_read_unlock(); 2206 } 2207 } 2208 2209 /* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might 2210 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak. 2211 * Note: for send buffers, TCP works better if we can build two skbs at 2212 * minimum. 2213 */ 2214 #define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff))) 2215 2216 #define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2) 2217 #define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE 2218 2219 static inline void sk_stream_moderate_sndbuf(struct sock *sk) 2220 { 2221 if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) { 2222 sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1); 2223 sk->sk_sndbuf = max_t(u32, sk->sk_sndbuf, SOCK_MIN_SNDBUF); 2224 } 2225 } 2226 2227 struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp, 2228 bool force_schedule); 2229 2230 /** 2231 * sk_page_frag - return an appropriate page_frag 2232 * @sk: socket 2233 * 2234 * If socket allocation mode allows current thread to sleep, it means its 2235 * safe to use the per task page_frag instead of the per socket one. 2236 */ 2237 static inline struct page_frag *sk_page_frag(struct sock *sk) 2238 { 2239 if (gfpflags_allow_blocking(sk->sk_allocation)) 2240 return ¤t->task_frag; 2241 2242 return &sk->sk_frag; 2243 } 2244 2245 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag); 2246 2247 /* 2248 * Default write policy as shown to user space via poll/select/SIGIO 2249 */ 2250 static inline bool sock_writeable(const struct sock *sk) 2251 { 2252 return refcount_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf >> 1); 2253 } 2254 2255 static inline gfp_t gfp_any(void) 2256 { 2257 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL; 2258 } 2259 2260 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock) 2261 { 2262 return noblock ? 0 : sk->sk_rcvtimeo; 2263 } 2264 2265 static inline long sock_sndtimeo(const struct sock *sk, bool noblock) 2266 { 2267 return noblock ? 0 : sk->sk_sndtimeo; 2268 } 2269 2270 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len) 2271 { 2272 return (waitall ? len : min_t(int, sk->sk_rcvlowat, len)) ? : 1; 2273 } 2274 2275 /* Alas, with timeout socket operations are not restartable. 2276 * Compare this to poll(). 2277 */ 2278 static inline int sock_intr_errno(long timeo) 2279 { 2280 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR; 2281 } 2282 2283 struct sock_skb_cb { 2284 u32 dropcount; 2285 }; 2286 2287 /* Store sock_skb_cb at the end of skb->cb[] so protocol families 2288 * using skb->cb[] would keep using it directly and utilize its 2289 * alignement guarantee. 2290 */ 2291 #define SOCK_SKB_CB_OFFSET ((FIELD_SIZEOF(struct sk_buff, cb) - \ 2292 sizeof(struct sock_skb_cb))) 2293 2294 #define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \ 2295 SOCK_SKB_CB_OFFSET)) 2296 2297 #define sock_skb_cb_check_size(size) \ 2298 BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET) 2299 2300 static inline void 2301 sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb) 2302 { 2303 SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ? 2304 atomic_read(&sk->sk_drops) : 0; 2305 } 2306 2307 static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb) 2308 { 2309 int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs); 2310 2311 atomic_add(segs, &sk->sk_drops); 2312 } 2313 2314 static inline ktime_t sock_read_timestamp(struct sock *sk) 2315 { 2316 #if BITS_PER_LONG==32 2317 unsigned int seq; 2318 ktime_t kt; 2319 2320 do { 2321 seq = read_seqbegin(&sk->sk_stamp_seq); 2322 kt = sk->sk_stamp; 2323 } while (read_seqretry(&sk->sk_stamp_seq, seq)); 2324 2325 return kt; 2326 #else 2327 return sk->sk_stamp; 2328 #endif 2329 } 2330 2331 static inline void sock_write_timestamp(struct sock *sk, ktime_t kt) 2332 { 2333 #if BITS_PER_LONG==32 2334 write_seqlock(&sk->sk_stamp_seq); 2335 sk->sk_stamp = kt; 2336 write_sequnlock(&sk->sk_stamp_seq); 2337 #else 2338 sk->sk_stamp = kt; 2339 #endif 2340 } 2341 2342 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk, 2343 struct sk_buff *skb); 2344 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk, 2345 struct sk_buff *skb); 2346 2347 static inline void 2348 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb) 2349 { 2350 ktime_t kt = skb->tstamp; 2351 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb); 2352 2353 /* 2354 * generate control messages if 2355 * - receive time stamping in software requested 2356 * - software time stamp available and wanted 2357 * - hardware time stamps available and wanted 2358 */ 2359 if (sock_flag(sk, SOCK_RCVTSTAMP) || 2360 (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) || 2361 (kt && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) || 2362 (hwtstamps->hwtstamp && 2363 (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE))) 2364 __sock_recv_timestamp(msg, sk, skb); 2365 else 2366 sock_write_timestamp(sk, kt); 2367 2368 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid) 2369 __sock_recv_wifi_status(msg, sk, skb); 2370 } 2371 2372 void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk, 2373 struct sk_buff *skb); 2374 2375 #define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC) 2376 static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk, 2377 struct sk_buff *skb) 2378 { 2379 #define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \ 2380 (1UL << SOCK_RCVTSTAMP)) 2381 #define TSFLAGS_ANY (SOF_TIMESTAMPING_SOFTWARE | \ 2382 SOF_TIMESTAMPING_RAW_HARDWARE) 2383 2384 if (sk->sk_flags & FLAGS_TS_OR_DROPS || sk->sk_tsflags & TSFLAGS_ANY) 2385 __sock_recv_ts_and_drops(msg, sk, skb); 2386 else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP))) 2387 sock_write_timestamp(sk, skb->tstamp); 2388 else if (unlikely(sk->sk_stamp == SK_DEFAULT_STAMP)) 2389 sock_write_timestamp(sk, 0); 2390 } 2391 2392 void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags); 2393 2394 /** 2395 * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped 2396 * @sk: socket sending this packet 2397 * @tsflags: timestamping flags to use 2398 * @tx_flags: completed with instructions for time stamping 2399 * @tskey: filled in with next sk_tskey (not for TCP, which uses seqno) 2400 * 2401 * Note: callers should take care of initial ``*tx_flags`` value (usually 0) 2402 */ 2403 static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags, 2404 __u8 *tx_flags, __u32 *tskey) 2405 { 2406 if (unlikely(tsflags)) { 2407 __sock_tx_timestamp(tsflags, tx_flags); 2408 if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey && 2409 tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK) 2410 *tskey = sk->sk_tskey++; 2411 } 2412 if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS))) 2413 *tx_flags |= SKBTX_WIFI_STATUS; 2414 } 2415 2416 static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags, 2417 __u8 *tx_flags) 2418 { 2419 _sock_tx_timestamp(sk, tsflags, tx_flags, NULL); 2420 } 2421 2422 static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags) 2423 { 2424 _sock_tx_timestamp(skb->sk, tsflags, &skb_shinfo(skb)->tx_flags, 2425 &skb_shinfo(skb)->tskey); 2426 } 2427 2428 /** 2429 * sk_eat_skb - Release a skb if it is no longer needed 2430 * @sk: socket to eat this skb from 2431 * @skb: socket buffer to eat 2432 * 2433 * This routine must be called with interrupts disabled or with the socket 2434 * locked so that the sk_buff queue operation is ok. 2435 */ 2436 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb) 2437 { 2438 __skb_unlink(skb, &sk->sk_receive_queue); 2439 if ( 2440 #ifdef CONFIG_RPS 2441 !static_branch_unlikely(&rps_needed) && 2442 #endif 2443 !sk->sk_rx_skb_cache) { 2444 sk->sk_rx_skb_cache = skb; 2445 skb_orphan(skb); 2446 return; 2447 } 2448 __kfree_skb(skb); 2449 } 2450 2451 static inline 2452 struct net *sock_net(const struct sock *sk) 2453 { 2454 return read_pnet(&sk->sk_net); 2455 } 2456 2457 static inline 2458 void sock_net_set(struct sock *sk, struct net *net) 2459 { 2460 write_pnet(&sk->sk_net, net); 2461 } 2462 2463 static inline struct sock *skb_steal_sock(struct sk_buff *skb) 2464 { 2465 if (skb->sk) { 2466 struct sock *sk = skb->sk; 2467 2468 skb->destructor = NULL; 2469 skb->sk = NULL; 2470 return sk; 2471 } 2472 return NULL; 2473 } 2474 2475 /* This helper checks if a socket is a full socket, 2476 * ie _not_ a timewait or request socket. 2477 */ 2478 static inline bool sk_fullsock(const struct sock *sk) 2479 { 2480 return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV); 2481 } 2482 2483 /* Checks if this SKB belongs to an HW offloaded socket 2484 * and whether any SW fallbacks are required based on dev. 2485 */ 2486 static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb, 2487 struct net_device *dev) 2488 { 2489 #ifdef CONFIG_SOCK_VALIDATE_XMIT 2490 struct sock *sk = skb->sk; 2491 2492 if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) 2493 skb = sk->sk_validate_xmit_skb(sk, dev, skb); 2494 #endif 2495 2496 return skb; 2497 } 2498 2499 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV 2500 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE) 2501 */ 2502 static inline bool sk_listener(const struct sock *sk) 2503 { 2504 return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV); 2505 } 2506 2507 void sock_enable_timestamp(struct sock *sk, int flag); 2508 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level, 2509 int type); 2510 2511 bool sk_ns_capable(const struct sock *sk, 2512 struct user_namespace *user_ns, int cap); 2513 bool sk_capable(const struct sock *sk, int cap); 2514 bool sk_net_capable(const struct sock *sk, int cap); 2515 2516 void sk_get_meminfo(const struct sock *sk, u32 *meminfo); 2517 2518 /* Take into consideration the size of the struct sk_buff overhead in the 2519 * determination of these values, since that is non-constant across 2520 * platforms. This makes socket queueing behavior and performance 2521 * not depend upon such differences. 2522 */ 2523 #define _SK_MEM_PACKETS 256 2524 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256) 2525 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 2526 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 2527 2528 extern __u32 sysctl_wmem_max; 2529 extern __u32 sysctl_rmem_max; 2530 2531 extern int sysctl_tstamp_allow_data; 2532 extern int sysctl_optmem_max; 2533 2534 extern __u32 sysctl_wmem_default; 2535 extern __u32 sysctl_rmem_default; 2536 2537 static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto) 2538 { 2539 /* Does this proto have per netns sysctl_wmem ? */ 2540 if (proto->sysctl_wmem_offset) 2541 return *(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset); 2542 2543 return *proto->sysctl_wmem; 2544 } 2545 2546 static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto) 2547 { 2548 /* Does this proto have per netns sysctl_rmem ? */ 2549 if (proto->sysctl_rmem_offset) 2550 return *(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset); 2551 2552 return *proto->sysctl_rmem; 2553 } 2554 2555 /* Default TCP Small queue budget is ~1 ms of data (1sec >> 10) 2556 * Some wifi drivers need to tweak it to get more chunks. 2557 * They can use this helper from their ndo_start_xmit() 2558 */ 2559 static inline void sk_pacing_shift_update(struct sock *sk, int val) 2560 { 2561 if (!sk || !sk_fullsock(sk) || sk->sk_pacing_shift == val) 2562 return; 2563 sk->sk_pacing_shift = val; 2564 } 2565 2566 /* if a socket is bound to a device, check that the given device 2567 * index is either the same or that the socket is bound to an L3 2568 * master device and the given device index is also enslaved to 2569 * that L3 master 2570 */ 2571 static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif) 2572 { 2573 int mdif; 2574 2575 if (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dif) 2576 return true; 2577 2578 mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif); 2579 if (mdif && mdif == sk->sk_bound_dev_if) 2580 return true; 2581 2582 return false; 2583 } 2584 2585 #endif /* _SOCK_H */ 2586