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/l3mdev.h> 70 71 /* 72 * This structure really needs to be cleaned up. 73 * Most of it is for TCP, and not used by any of 74 * the other protocols. 75 */ 76 77 /* Define this to get the SOCK_DBG debugging facility. */ 78 #define SOCK_DEBUGGING 79 #ifdef SOCK_DEBUGGING 80 #define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \ 81 printk(KERN_DEBUG msg); } while (0) 82 #else 83 /* Validate arguments and do nothing */ 84 static inline __printf(2, 3) 85 void SOCK_DEBUG(const struct sock *sk, const char *msg, ...) 86 { 87 } 88 #endif 89 90 /* This is the per-socket lock. The spinlock provides a synchronization 91 * between user contexts and software interrupt processing, whereas the 92 * mini-semaphore synchronizes multiple users amongst themselves. 93 */ 94 typedef struct { 95 spinlock_t slock; 96 int owned; 97 wait_queue_head_t wq; 98 /* 99 * We express the mutex-alike socket_lock semantics 100 * to the lock validator by explicitly managing 101 * the slock as a lock variant (in addition to 102 * the slock itself): 103 */ 104 #ifdef CONFIG_DEBUG_LOCK_ALLOC 105 struct lockdep_map dep_map; 106 #endif 107 } socket_lock_t; 108 109 struct sock; 110 struct proto; 111 struct net; 112 113 typedef __u32 __bitwise __portpair; 114 typedef __u64 __bitwise __addrpair; 115 116 /** 117 * struct sock_common - minimal network layer representation of sockets 118 * @skc_daddr: Foreign IPv4 addr 119 * @skc_rcv_saddr: Bound local IPv4 addr 120 * @skc_hash: hash value used with various protocol lookup tables 121 * @skc_u16hashes: two u16 hash values used by UDP lookup tables 122 * @skc_dport: placeholder for inet_dport/tw_dport 123 * @skc_num: placeholder for inet_num/tw_num 124 * @skc_family: network address family 125 * @skc_state: Connection state 126 * @skc_reuse: %SO_REUSEADDR setting 127 * @skc_reuseport: %SO_REUSEPORT setting 128 * @skc_bound_dev_if: bound device index if != 0 129 * @skc_bind_node: bind hash linkage for various protocol lookup tables 130 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol 131 * @skc_prot: protocol handlers inside a network family 132 * @skc_net: reference to the network namespace of this socket 133 * @skc_node: main hash linkage for various protocol lookup tables 134 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol 135 * @skc_tx_queue_mapping: tx queue number for this connection 136 * @skc_rx_queue_mapping: rx queue number for this connection 137 * @skc_flags: place holder for sk_flags 138 * %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE, 139 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings 140 * @skc_incoming_cpu: record/match cpu processing incoming packets 141 * @skc_refcnt: reference count 142 * 143 * This is the minimal network layer representation of sockets, the header 144 * for struct sock and struct inet_timewait_sock. 145 */ 146 struct sock_common { 147 /* skc_daddr and skc_rcv_saddr must be grouped on a 8 bytes aligned 148 * address on 64bit arches : cf INET_MATCH() 149 */ 150 union { 151 __addrpair skc_addrpair; 152 struct { 153 __be32 skc_daddr; 154 __be32 skc_rcv_saddr; 155 }; 156 }; 157 union { 158 unsigned int skc_hash; 159 __u16 skc_u16hashes[2]; 160 }; 161 /* skc_dport && skc_num must be grouped as well */ 162 union { 163 __portpair skc_portpair; 164 struct { 165 __be16 skc_dport; 166 __u16 skc_num; 167 }; 168 }; 169 170 unsigned short skc_family; 171 volatile unsigned char skc_state; 172 unsigned char skc_reuse:4; 173 unsigned char skc_reuseport:1; 174 unsigned char skc_ipv6only:1; 175 unsigned char skc_net_refcnt:1; 176 int skc_bound_dev_if; 177 union { 178 struct hlist_node skc_bind_node; 179 struct hlist_node skc_portaddr_node; 180 }; 181 struct proto *skc_prot; 182 possible_net_t skc_net; 183 184 #if IS_ENABLED(CONFIG_IPV6) 185 struct in6_addr skc_v6_daddr; 186 struct in6_addr skc_v6_rcv_saddr; 187 #endif 188 189 atomic64_t skc_cookie; 190 191 /* following fields are padding to force 192 * offset(struct sock, sk_refcnt) == 128 on 64bit arches 193 * assuming IPV6 is enabled. We use this padding differently 194 * for different kind of 'sockets' 195 */ 196 union { 197 unsigned long skc_flags; 198 struct sock *skc_listener; /* request_sock */ 199 struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */ 200 }; 201 /* 202 * fields between dontcopy_begin/dontcopy_end 203 * are not copied in sock_copy() 204 */ 205 /* private: */ 206 int skc_dontcopy_begin[0]; 207 /* public: */ 208 union { 209 struct hlist_node skc_node; 210 struct hlist_nulls_node skc_nulls_node; 211 }; 212 unsigned short skc_tx_queue_mapping; 213 #ifdef CONFIG_XPS 214 unsigned short skc_rx_queue_mapping; 215 #endif 216 union { 217 int skc_incoming_cpu; 218 u32 skc_rcv_wnd; 219 u32 skc_tw_rcv_nxt; /* struct tcp_timewait_sock */ 220 }; 221 222 refcount_t skc_refcnt; 223 /* private: */ 224 int skc_dontcopy_end[0]; 225 union { 226 u32 skc_rxhash; 227 u32 skc_window_clamp; 228 u32 skc_tw_snd_nxt; /* struct tcp_timewait_sock */ 229 }; 230 /* public: */ 231 }; 232 233 struct bpf_sk_storage; 234 235 /** 236 * struct sock - network layer representation of sockets 237 * @__sk_common: shared layout with inet_timewait_sock 238 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN 239 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings 240 * @sk_lock: synchronizer 241 * @sk_kern_sock: True if sock is using kernel lock classes 242 * @sk_rcvbuf: size of receive buffer in bytes 243 * @sk_wq: sock wait queue and async head 244 * @sk_rx_dst: receive input route used by early demux 245 * @sk_dst_cache: destination cache 246 * @sk_dst_pending_confirm: need to confirm neighbour 247 * @sk_policy: flow policy 248 * @sk_receive_queue: incoming packets 249 * @sk_wmem_alloc: transmit queue bytes committed 250 * @sk_tsq_flags: TCP Small Queues flags 251 * @sk_write_queue: Packet sending queue 252 * @sk_omem_alloc: "o" is "option" or "other" 253 * @sk_wmem_queued: persistent queue size 254 * @sk_forward_alloc: space allocated forward 255 * @sk_napi_id: id of the last napi context to receive data for sk 256 * @sk_ll_usec: usecs to busypoll when there is no data 257 * @sk_allocation: allocation mode 258 * @sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler) 259 * @sk_pacing_status: Pacing status (requested, handled by sch_fq) 260 * @sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE) 261 * @sk_sndbuf: size of send buffer in bytes 262 * @__sk_flags_offset: empty field used to determine location of bitfield 263 * @sk_padding: unused element for alignment 264 * @sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets 265 * @sk_no_check_rx: allow zero checksum in RX packets 266 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO) 267 * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK) 268 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4) 269 * @sk_gso_max_size: Maximum GSO segment size to build 270 * @sk_gso_max_segs: Maximum number of GSO segments 271 * @sk_pacing_shift: scaling factor for TCP Small Queues 272 * @sk_lingertime: %SO_LINGER l_linger setting 273 * @sk_backlog: always used with the per-socket spinlock held 274 * @sk_callback_lock: used with the callbacks in the end of this struct 275 * @sk_error_queue: rarely used 276 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt, 277 * IPV6_ADDRFORM for instance) 278 * @sk_err: last error 279 * @sk_err_soft: errors that don't cause failure but are the cause of a 280 * persistent failure not just 'timed out' 281 * @sk_drops: raw/udp drops counter 282 * @sk_ack_backlog: current listen backlog 283 * @sk_max_ack_backlog: listen backlog set in listen() 284 * @sk_uid: user id of owner 285 * @sk_priority: %SO_PRIORITY setting 286 * @sk_type: socket type (%SOCK_STREAM, etc) 287 * @sk_protocol: which protocol this socket belongs in this network family 288 * @sk_peer_pid: &struct pid for this socket's peer 289 * @sk_peer_cred: %SO_PEERCRED setting 290 * @sk_rcvlowat: %SO_RCVLOWAT setting 291 * @sk_rcvtimeo: %SO_RCVTIMEO setting 292 * @sk_sndtimeo: %SO_SNDTIMEO setting 293 * @sk_txhash: computed flow hash for use on transmit 294 * @sk_filter: socket filtering instructions 295 * @sk_timer: sock cleanup timer 296 * @sk_stamp: time stamp of last packet received 297 * @sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only 298 * @sk_tsflags: SO_TIMESTAMPING socket options 299 * @sk_tskey: counter to disambiguate concurrent tstamp requests 300 * @sk_zckey: counter to order MSG_ZEROCOPY notifications 301 * @sk_socket: Identd and reporting IO signals 302 * @sk_user_data: RPC layer private data 303 * @sk_frag: cached page frag 304 * @sk_peek_off: current peek_offset value 305 * @sk_send_head: front of stuff to transmit 306 * @sk_security: used by security modules 307 * @sk_mark: generic packet mark 308 * @sk_cgrp_data: cgroup data for this cgroup 309 * @sk_memcg: this socket's memory cgroup association 310 * @sk_write_pending: a write to stream socket waits to start 311 * @sk_state_change: callback to indicate change in the state of the sock 312 * @sk_data_ready: callback to indicate there is data to be processed 313 * @sk_write_space: callback to indicate there is bf sending space available 314 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE) 315 * @sk_backlog_rcv: callback to process the backlog 316 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0 317 * @sk_reuseport_cb: reuseport group container 318 * @sk_rcu: used during RCU grace period 319 * @sk_clockid: clockid used by time-based scheduling (SO_TXTIME) 320 * @sk_txtime_deadline_mode: set deadline mode for SO_TXTIME 321 * @sk_txtime_unused: unused txtime flags 322 */ 323 struct sock { 324 /* 325 * Now struct inet_timewait_sock also uses sock_common, so please just 326 * don't add nothing before this first member (__sk_common) --acme 327 */ 328 struct sock_common __sk_common; 329 #define sk_node __sk_common.skc_node 330 #define sk_nulls_node __sk_common.skc_nulls_node 331 #define sk_refcnt __sk_common.skc_refcnt 332 #define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping 333 #ifdef CONFIG_XPS 334 #define sk_rx_queue_mapping __sk_common.skc_rx_queue_mapping 335 #endif 336 337 #define sk_dontcopy_begin __sk_common.skc_dontcopy_begin 338 #define sk_dontcopy_end __sk_common.skc_dontcopy_end 339 #define sk_hash __sk_common.skc_hash 340 #define sk_portpair __sk_common.skc_portpair 341 #define sk_num __sk_common.skc_num 342 #define sk_dport __sk_common.skc_dport 343 #define sk_addrpair __sk_common.skc_addrpair 344 #define sk_daddr __sk_common.skc_daddr 345 #define sk_rcv_saddr __sk_common.skc_rcv_saddr 346 #define sk_family __sk_common.skc_family 347 #define sk_state __sk_common.skc_state 348 #define sk_reuse __sk_common.skc_reuse 349 #define sk_reuseport __sk_common.skc_reuseport 350 #define sk_ipv6only __sk_common.skc_ipv6only 351 #define sk_net_refcnt __sk_common.skc_net_refcnt 352 #define sk_bound_dev_if __sk_common.skc_bound_dev_if 353 #define sk_bind_node __sk_common.skc_bind_node 354 #define sk_prot __sk_common.skc_prot 355 #define sk_net __sk_common.skc_net 356 #define sk_v6_daddr __sk_common.skc_v6_daddr 357 #define sk_v6_rcv_saddr __sk_common.skc_v6_rcv_saddr 358 #define sk_cookie __sk_common.skc_cookie 359 #define sk_incoming_cpu __sk_common.skc_incoming_cpu 360 #define sk_flags __sk_common.skc_flags 361 #define sk_rxhash __sk_common.skc_rxhash 362 363 socket_lock_t sk_lock; 364 atomic_t sk_drops; 365 int sk_rcvlowat; 366 struct sk_buff_head sk_error_queue; 367 struct sk_buff *sk_rx_skb_cache; 368 struct sk_buff_head sk_receive_queue; 369 /* 370 * The backlog queue is special, it is always used with 371 * the per-socket spinlock held and requires low latency 372 * access. Therefore we special case it's implementation. 373 * Note : rmem_alloc is in this structure to fill a hole 374 * on 64bit arches, not because its logically part of 375 * backlog. 376 */ 377 struct { 378 atomic_t rmem_alloc; 379 int len; 380 struct sk_buff *head; 381 struct sk_buff *tail; 382 } sk_backlog; 383 #define sk_rmem_alloc sk_backlog.rmem_alloc 384 385 int sk_forward_alloc; 386 #ifdef CONFIG_NET_RX_BUSY_POLL 387 unsigned int sk_ll_usec; 388 /* ===== mostly read cache line ===== */ 389 unsigned int sk_napi_id; 390 #endif 391 int sk_rcvbuf; 392 393 struct sk_filter __rcu *sk_filter; 394 union { 395 struct socket_wq __rcu *sk_wq; 396 struct socket_wq *sk_wq_raw; 397 }; 398 #ifdef CONFIG_XFRM 399 struct xfrm_policy __rcu *sk_policy[2]; 400 #endif 401 struct dst_entry *sk_rx_dst; 402 struct dst_entry __rcu *sk_dst_cache; 403 atomic_t sk_omem_alloc; 404 int sk_sndbuf; 405 406 /* ===== cache line for TX ===== */ 407 int sk_wmem_queued; 408 refcount_t sk_wmem_alloc; 409 unsigned long sk_tsq_flags; 410 union { 411 struct sk_buff *sk_send_head; 412 struct rb_root tcp_rtx_queue; 413 }; 414 struct sk_buff *sk_tx_skb_cache; 415 struct sk_buff_head sk_write_queue; 416 __s32 sk_peek_off; 417 int sk_write_pending; 418 __u32 sk_dst_pending_confirm; 419 u32 sk_pacing_status; /* see enum sk_pacing */ 420 long sk_sndtimeo; 421 struct timer_list sk_timer; 422 __u32 sk_priority; 423 __u32 sk_mark; 424 unsigned long sk_pacing_rate; /* bytes per second */ 425 unsigned long sk_max_pacing_rate; 426 struct page_frag sk_frag; 427 netdev_features_t sk_route_caps; 428 netdev_features_t sk_route_nocaps; 429 netdev_features_t sk_route_forced_caps; 430 int sk_gso_type; 431 unsigned int sk_gso_max_size; 432 gfp_t sk_allocation; 433 __u32 sk_txhash; 434 435 /* 436 * Because of non atomicity rules, all 437 * changes are protected by socket lock. 438 */ 439 unsigned int __sk_flags_offset[0]; 440 #ifdef __BIG_ENDIAN_BITFIELD 441 #define SK_FL_PROTO_SHIFT 16 442 #define SK_FL_PROTO_MASK 0x00ff0000 443 444 #define SK_FL_TYPE_SHIFT 0 445 #define SK_FL_TYPE_MASK 0x0000ffff 446 #else 447 #define SK_FL_PROTO_SHIFT 8 448 #define SK_FL_PROTO_MASK 0x0000ff00 449 450 #define SK_FL_TYPE_SHIFT 16 451 #define SK_FL_TYPE_MASK 0xffff0000 452 #endif 453 454 unsigned int sk_padding : 1, 455 sk_kern_sock : 1, 456 sk_no_check_tx : 1, 457 sk_no_check_rx : 1, 458 sk_userlocks : 4, 459 sk_protocol : 8, 460 sk_type : 16; 461 #define SK_PROTOCOL_MAX U8_MAX 462 u16 sk_gso_max_segs; 463 u8 sk_pacing_shift; 464 unsigned long sk_lingertime; 465 struct proto *sk_prot_creator; 466 rwlock_t sk_callback_lock; 467 int sk_err, 468 sk_err_soft; 469 u32 sk_ack_backlog; 470 u32 sk_max_ack_backlog; 471 kuid_t sk_uid; 472 struct pid *sk_peer_pid; 473 const struct cred *sk_peer_cred; 474 long sk_rcvtimeo; 475 ktime_t sk_stamp; 476 #if BITS_PER_LONG==32 477 seqlock_t sk_stamp_seq; 478 #endif 479 u16 sk_tsflags; 480 u8 sk_shutdown; 481 u32 sk_tskey; 482 atomic_t sk_zckey; 483 484 u8 sk_clockid; 485 u8 sk_txtime_deadline_mode : 1, 486 sk_txtime_report_errors : 1, 487 sk_txtime_unused : 6; 488 489 struct socket *sk_socket; 490 void *sk_user_data; 491 #ifdef CONFIG_SECURITY 492 void *sk_security; 493 #endif 494 struct sock_cgroup_data sk_cgrp_data; 495 struct mem_cgroup *sk_memcg; 496 void (*sk_state_change)(struct sock *sk); 497 void (*sk_data_ready)(struct sock *sk); 498 void (*sk_write_space)(struct sock *sk); 499 void (*sk_error_report)(struct sock *sk); 500 int (*sk_backlog_rcv)(struct sock *sk, 501 struct sk_buff *skb); 502 #ifdef CONFIG_SOCK_VALIDATE_XMIT 503 struct sk_buff* (*sk_validate_xmit_skb)(struct sock *sk, 504 struct net_device *dev, 505 struct sk_buff *skb); 506 #endif 507 void (*sk_destruct)(struct sock *sk); 508 struct sock_reuseport __rcu *sk_reuseport_cb; 509 #ifdef CONFIG_BPF_SYSCALL 510 struct bpf_sk_storage __rcu *sk_bpf_storage; 511 #endif 512 struct rcu_head sk_rcu; 513 }; 514 515 enum sk_pacing { 516 SK_PACING_NONE = 0, 517 SK_PACING_NEEDED = 1, 518 SK_PACING_FQ = 2, 519 }; 520 521 #define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data))) 522 523 #define rcu_dereference_sk_user_data(sk) rcu_dereference(__sk_user_data((sk))) 524 #define rcu_assign_sk_user_data(sk, ptr) rcu_assign_pointer(__sk_user_data((sk)), ptr) 525 526 /* 527 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK 528 * or not whether his port will be reused by someone else. SK_FORCE_REUSE 529 * on a socket means that the socket will reuse everybody else's port 530 * without looking at the other's sk_reuse value. 531 */ 532 533 #define SK_NO_REUSE 0 534 #define SK_CAN_REUSE 1 535 #define SK_FORCE_REUSE 2 536 537 int sk_set_peek_off(struct sock *sk, int val); 538 539 static inline int sk_peek_offset(struct sock *sk, int flags) 540 { 541 if (unlikely(flags & MSG_PEEK)) { 542 return READ_ONCE(sk->sk_peek_off); 543 } 544 545 return 0; 546 } 547 548 static inline void sk_peek_offset_bwd(struct sock *sk, int val) 549 { 550 s32 off = READ_ONCE(sk->sk_peek_off); 551 552 if (unlikely(off >= 0)) { 553 off = max_t(s32, off - val, 0); 554 WRITE_ONCE(sk->sk_peek_off, off); 555 } 556 } 557 558 static inline void sk_peek_offset_fwd(struct sock *sk, int val) 559 { 560 sk_peek_offset_bwd(sk, -val); 561 } 562 563 /* 564 * Hashed lists helper routines 565 */ 566 static inline struct sock *sk_entry(const struct hlist_node *node) 567 { 568 return hlist_entry(node, struct sock, sk_node); 569 } 570 571 static inline struct sock *__sk_head(const struct hlist_head *head) 572 { 573 return hlist_entry(head->first, struct sock, sk_node); 574 } 575 576 static inline struct sock *sk_head(const struct hlist_head *head) 577 { 578 return hlist_empty(head) ? NULL : __sk_head(head); 579 } 580 581 static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head) 582 { 583 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node); 584 } 585 586 static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head) 587 { 588 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head); 589 } 590 591 static inline struct sock *sk_next(const struct sock *sk) 592 { 593 return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node); 594 } 595 596 static inline struct sock *sk_nulls_next(const struct sock *sk) 597 { 598 return (!is_a_nulls(sk->sk_nulls_node.next)) ? 599 hlist_nulls_entry(sk->sk_nulls_node.next, 600 struct sock, sk_nulls_node) : 601 NULL; 602 } 603 604 static inline bool sk_unhashed(const struct sock *sk) 605 { 606 return hlist_unhashed(&sk->sk_node); 607 } 608 609 static inline bool sk_hashed(const struct sock *sk) 610 { 611 return !sk_unhashed(sk); 612 } 613 614 static inline void sk_node_init(struct hlist_node *node) 615 { 616 node->pprev = NULL; 617 } 618 619 static inline void sk_nulls_node_init(struct hlist_nulls_node *node) 620 { 621 node->pprev = NULL; 622 } 623 624 static inline void __sk_del_node(struct sock *sk) 625 { 626 __hlist_del(&sk->sk_node); 627 } 628 629 /* NB: equivalent to hlist_del_init_rcu */ 630 static inline bool __sk_del_node_init(struct sock *sk) 631 { 632 if (sk_hashed(sk)) { 633 __sk_del_node(sk); 634 sk_node_init(&sk->sk_node); 635 return true; 636 } 637 return false; 638 } 639 640 /* Grab socket reference count. This operation is valid only 641 when sk is ALREADY grabbed f.e. it is found in hash table 642 or a list and the lookup is made under lock preventing hash table 643 modifications. 644 */ 645 646 static __always_inline void sock_hold(struct sock *sk) 647 { 648 refcount_inc(&sk->sk_refcnt); 649 } 650 651 /* Ungrab socket in the context, which assumes that socket refcnt 652 cannot hit zero, f.e. it is true in context of any socketcall. 653 */ 654 static __always_inline void __sock_put(struct sock *sk) 655 { 656 refcount_dec(&sk->sk_refcnt); 657 } 658 659 static inline bool sk_del_node_init(struct sock *sk) 660 { 661 bool rc = __sk_del_node_init(sk); 662 663 if (rc) { 664 /* paranoid for a while -acme */ 665 WARN_ON(refcount_read(&sk->sk_refcnt) == 1); 666 __sock_put(sk); 667 } 668 return rc; 669 } 670 #define sk_del_node_init_rcu(sk) sk_del_node_init(sk) 671 672 static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk) 673 { 674 if (sk_hashed(sk)) { 675 hlist_nulls_del_init_rcu(&sk->sk_nulls_node); 676 return true; 677 } 678 return false; 679 } 680 681 static inline bool sk_nulls_del_node_init_rcu(struct sock *sk) 682 { 683 bool rc = __sk_nulls_del_node_init_rcu(sk); 684 685 if (rc) { 686 /* paranoid for a while -acme */ 687 WARN_ON(refcount_read(&sk->sk_refcnt) == 1); 688 __sock_put(sk); 689 } 690 return rc; 691 } 692 693 static inline void __sk_add_node(struct sock *sk, struct hlist_head *list) 694 { 695 hlist_add_head(&sk->sk_node, list); 696 } 697 698 static inline void sk_add_node(struct sock *sk, struct hlist_head *list) 699 { 700 sock_hold(sk); 701 __sk_add_node(sk, list); 702 } 703 704 static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list) 705 { 706 sock_hold(sk); 707 if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport && 708 sk->sk_family == AF_INET6) 709 hlist_add_tail_rcu(&sk->sk_node, list); 710 else 711 hlist_add_head_rcu(&sk->sk_node, list); 712 } 713 714 static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list) 715 { 716 sock_hold(sk); 717 hlist_add_tail_rcu(&sk->sk_node, list); 718 } 719 720 static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list) 721 { 722 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list); 723 } 724 725 static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list) 726 { 727 sock_hold(sk); 728 __sk_nulls_add_node_rcu(sk, list); 729 } 730 731 static inline void __sk_del_bind_node(struct sock *sk) 732 { 733 __hlist_del(&sk->sk_bind_node); 734 } 735 736 static inline void sk_add_bind_node(struct sock *sk, 737 struct hlist_head *list) 738 { 739 hlist_add_head(&sk->sk_bind_node, list); 740 } 741 742 #define sk_for_each(__sk, list) \ 743 hlist_for_each_entry(__sk, list, sk_node) 744 #define sk_for_each_rcu(__sk, list) \ 745 hlist_for_each_entry_rcu(__sk, list, sk_node) 746 #define sk_nulls_for_each(__sk, node, list) \ 747 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node) 748 #define sk_nulls_for_each_rcu(__sk, node, list) \ 749 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node) 750 #define sk_for_each_from(__sk) \ 751 hlist_for_each_entry_from(__sk, sk_node) 752 #define sk_nulls_for_each_from(__sk, node) \ 753 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \ 754 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node) 755 #define sk_for_each_safe(__sk, tmp, list) \ 756 hlist_for_each_entry_safe(__sk, tmp, list, sk_node) 757 #define sk_for_each_bound(__sk, list) \ 758 hlist_for_each_entry(__sk, list, sk_bind_node) 759 760 /** 761 * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset 762 * @tpos: the type * to use as a loop cursor. 763 * @pos: the &struct hlist_node to use as a loop cursor. 764 * @head: the head for your list. 765 * @offset: offset of hlist_node within the struct. 766 * 767 */ 768 #define sk_for_each_entry_offset_rcu(tpos, pos, head, offset) \ 769 for (pos = rcu_dereference(hlist_first_rcu(head)); \ 770 pos != NULL && \ 771 ({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \ 772 pos = rcu_dereference(hlist_next_rcu(pos))) 773 774 static inline struct user_namespace *sk_user_ns(struct sock *sk) 775 { 776 /* Careful only use this in a context where these parameters 777 * can not change and must all be valid, such as recvmsg from 778 * userspace. 779 */ 780 return sk->sk_socket->file->f_cred->user_ns; 781 } 782 783 /* Sock flags */ 784 enum sock_flags { 785 SOCK_DEAD, 786 SOCK_DONE, 787 SOCK_URGINLINE, 788 SOCK_KEEPOPEN, 789 SOCK_LINGER, 790 SOCK_DESTROY, 791 SOCK_BROADCAST, 792 SOCK_TIMESTAMP, 793 SOCK_ZAPPED, 794 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */ 795 SOCK_DBG, /* %SO_DEBUG setting */ 796 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */ 797 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */ 798 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */ 799 SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */ 800 SOCK_MEMALLOC, /* VM depends on this socket for swapping */ 801 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */ 802 SOCK_FASYNC, /* fasync() active */ 803 SOCK_RXQ_OVFL, 804 SOCK_ZEROCOPY, /* buffers from userspace */ 805 SOCK_WIFI_STATUS, /* push wifi status to userspace */ 806 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS. 807 * Will use last 4 bytes of packet sent from 808 * user-space instead. 809 */ 810 SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */ 811 SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */ 812 SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */ 813 SOCK_TXTIME, 814 SOCK_XDP, /* XDP is attached */ 815 SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */ 816 }; 817 818 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)) 819 820 static inline void sock_copy_flags(struct sock *nsk, struct sock *osk) 821 { 822 nsk->sk_flags = osk->sk_flags; 823 } 824 825 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag) 826 { 827 __set_bit(flag, &sk->sk_flags); 828 } 829 830 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag) 831 { 832 __clear_bit(flag, &sk->sk_flags); 833 } 834 835 static inline bool sock_flag(const struct sock *sk, enum sock_flags flag) 836 { 837 return test_bit(flag, &sk->sk_flags); 838 } 839 840 #ifdef CONFIG_NET 841 DECLARE_STATIC_KEY_FALSE(memalloc_socks_key); 842 static inline int sk_memalloc_socks(void) 843 { 844 return static_branch_unlikely(&memalloc_socks_key); 845 } 846 #else 847 848 static inline int sk_memalloc_socks(void) 849 { 850 return 0; 851 } 852 853 #endif 854 855 static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask) 856 { 857 return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC); 858 } 859 860 static inline void sk_acceptq_removed(struct sock *sk) 861 { 862 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1); 863 } 864 865 static inline void sk_acceptq_added(struct sock *sk) 866 { 867 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1); 868 } 869 870 static inline bool sk_acceptq_is_full(const struct sock *sk) 871 { 872 return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(sk->sk_max_ack_backlog); 873 } 874 875 /* 876 * Compute minimal free write space needed to queue new packets. 877 */ 878 static inline int sk_stream_min_wspace(const struct sock *sk) 879 { 880 return READ_ONCE(sk->sk_wmem_queued) >> 1; 881 } 882 883 static inline int sk_stream_wspace(const struct sock *sk) 884 { 885 return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued); 886 } 887 888 static inline void sk_wmem_queued_add(struct sock *sk, int val) 889 { 890 WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val); 891 } 892 893 void sk_stream_write_space(struct sock *sk); 894 895 /* OOB backlog add */ 896 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb) 897 { 898 /* dont let skb dst not refcounted, we are going to leave rcu lock */ 899 skb_dst_force(skb); 900 901 if (!sk->sk_backlog.tail) 902 WRITE_ONCE(sk->sk_backlog.head, skb); 903 else 904 sk->sk_backlog.tail->next = skb; 905 906 WRITE_ONCE(sk->sk_backlog.tail, skb); 907 skb->next = NULL; 908 } 909 910 /* 911 * Take into account size of receive queue and backlog queue 912 * Do not take into account this skb truesize, 913 * to allow even a single big packet to come. 914 */ 915 static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit) 916 { 917 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc); 918 919 return qsize > limit; 920 } 921 922 /* The per-socket spinlock must be held here. */ 923 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb, 924 unsigned int limit) 925 { 926 if (sk_rcvqueues_full(sk, limit)) 927 return -ENOBUFS; 928 929 /* 930 * If the skb was allocated from pfmemalloc reserves, only 931 * allow SOCK_MEMALLOC sockets to use it as this socket is 932 * helping free memory 933 */ 934 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) 935 return -ENOMEM; 936 937 __sk_add_backlog(sk, skb); 938 sk->sk_backlog.len += skb->truesize; 939 return 0; 940 } 941 942 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb); 943 944 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 945 { 946 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) 947 return __sk_backlog_rcv(sk, skb); 948 949 return sk->sk_backlog_rcv(sk, skb); 950 } 951 952 static inline void sk_incoming_cpu_update(struct sock *sk) 953 { 954 int cpu = raw_smp_processor_id(); 955 956 if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu)) 957 WRITE_ONCE(sk->sk_incoming_cpu, cpu); 958 } 959 960 static inline void sock_rps_record_flow_hash(__u32 hash) 961 { 962 #ifdef CONFIG_RPS 963 struct rps_sock_flow_table *sock_flow_table; 964 965 rcu_read_lock(); 966 sock_flow_table = rcu_dereference(rps_sock_flow_table); 967 rps_record_sock_flow(sock_flow_table, hash); 968 rcu_read_unlock(); 969 #endif 970 } 971 972 static inline void sock_rps_record_flow(const struct sock *sk) 973 { 974 #ifdef CONFIG_RPS 975 if (static_branch_unlikely(&rfs_needed)) { 976 /* Reading sk->sk_rxhash might incur an expensive cache line 977 * miss. 978 * 979 * TCP_ESTABLISHED does cover almost all states where RFS 980 * might be useful, and is cheaper [1] than testing : 981 * IPv4: inet_sk(sk)->inet_daddr 982 * IPv6: ipv6_addr_any(&sk->sk_v6_daddr) 983 * OR an additional socket flag 984 * [1] : sk_state and sk_prot are in the same cache line. 985 */ 986 if (sk->sk_state == TCP_ESTABLISHED) 987 sock_rps_record_flow_hash(sk->sk_rxhash); 988 } 989 #endif 990 } 991 992 static inline void sock_rps_save_rxhash(struct sock *sk, 993 const struct sk_buff *skb) 994 { 995 #ifdef CONFIG_RPS 996 if (unlikely(sk->sk_rxhash != skb->hash)) 997 sk->sk_rxhash = skb->hash; 998 #endif 999 } 1000 1001 static inline void sock_rps_reset_rxhash(struct sock *sk) 1002 { 1003 #ifdef CONFIG_RPS 1004 sk->sk_rxhash = 0; 1005 #endif 1006 } 1007 1008 #define sk_wait_event(__sk, __timeo, __condition, __wait) \ 1009 ({ int __rc; \ 1010 release_sock(__sk); \ 1011 __rc = __condition; \ 1012 if (!__rc) { \ 1013 *(__timeo) = wait_woken(__wait, \ 1014 TASK_INTERRUPTIBLE, \ 1015 *(__timeo)); \ 1016 } \ 1017 sched_annotate_sleep(); \ 1018 lock_sock(__sk); \ 1019 __rc = __condition; \ 1020 __rc; \ 1021 }) 1022 1023 int sk_stream_wait_connect(struct sock *sk, long *timeo_p); 1024 int sk_stream_wait_memory(struct sock *sk, long *timeo_p); 1025 void sk_stream_wait_close(struct sock *sk, long timeo_p); 1026 int sk_stream_error(struct sock *sk, int flags, int err); 1027 void sk_stream_kill_queues(struct sock *sk); 1028 void sk_set_memalloc(struct sock *sk); 1029 void sk_clear_memalloc(struct sock *sk); 1030 1031 void __sk_flush_backlog(struct sock *sk); 1032 1033 static inline bool sk_flush_backlog(struct sock *sk) 1034 { 1035 if (unlikely(READ_ONCE(sk->sk_backlog.tail))) { 1036 __sk_flush_backlog(sk); 1037 return true; 1038 } 1039 return false; 1040 } 1041 1042 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb); 1043 1044 struct request_sock_ops; 1045 struct timewait_sock_ops; 1046 struct inet_hashinfo; 1047 struct raw_hashinfo; 1048 struct smc_hashinfo; 1049 struct module; 1050 1051 /* 1052 * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes 1053 * un-modified. Special care is taken when initializing object to zero. 1054 */ 1055 static inline void sk_prot_clear_nulls(struct sock *sk, int size) 1056 { 1057 if (offsetof(struct sock, sk_node.next) != 0) 1058 memset(sk, 0, offsetof(struct sock, sk_node.next)); 1059 memset(&sk->sk_node.pprev, 0, 1060 size - offsetof(struct sock, sk_node.pprev)); 1061 } 1062 1063 /* Networking protocol blocks we attach to sockets. 1064 * socket layer -> transport layer interface 1065 */ 1066 struct proto { 1067 void (*close)(struct sock *sk, 1068 long timeout); 1069 int (*pre_connect)(struct sock *sk, 1070 struct sockaddr *uaddr, 1071 int addr_len); 1072 int (*connect)(struct sock *sk, 1073 struct sockaddr *uaddr, 1074 int addr_len); 1075 int (*disconnect)(struct sock *sk, int flags); 1076 1077 struct sock * (*accept)(struct sock *sk, int flags, int *err, 1078 bool kern); 1079 1080 int (*ioctl)(struct sock *sk, int cmd, 1081 unsigned long arg); 1082 int (*init)(struct sock *sk); 1083 void (*destroy)(struct sock *sk); 1084 void (*shutdown)(struct sock *sk, int how); 1085 int (*setsockopt)(struct sock *sk, int level, 1086 int optname, char __user *optval, 1087 unsigned int optlen); 1088 int (*getsockopt)(struct sock *sk, int level, 1089 int optname, char __user *optval, 1090 int __user *option); 1091 void (*keepalive)(struct sock *sk, int valbool); 1092 #ifdef CONFIG_COMPAT 1093 int (*compat_setsockopt)(struct sock *sk, 1094 int level, 1095 int optname, char __user *optval, 1096 unsigned int optlen); 1097 int (*compat_getsockopt)(struct sock *sk, 1098 int level, 1099 int optname, char __user *optval, 1100 int __user *option); 1101 int (*compat_ioctl)(struct sock *sk, 1102 unsigned int cmd, unsigned long arg); 1103 #endif 1104 int (*sendmsg)(struct sock *sk, struct msghdr *msg, 1105 size_t len); 1106 int (*recvmsg)(struct sock *sk, struct msghdr *msg, 1107 size_t len, int noblock, int flags, 1108 int *addr_len); 1109 int (*sendpage)(struct sock *sk, struct page *page, 1110 int offset, size_t size, int flags); 1111 int (*bind)(struct sock *sk, 1112 struct sockaddr *uaddr, int addr_len); 1113 1114 int (*backlog_rcv) (struct sock *sk, 1115 struct sk_buff *skb); 1116 1117 void (*release_cb)(struct sock *sk); 1118 1119 /* Keeping track of sk's, looking them up, and port selection methods. */ 1120 int (*hash)(struct sock *sk); 1121 void (*unhash)(struct sock *sk); 1122 void (*rehash)(struct sock *sk); 1123 int (*get_port)(struct sock *sk, unsigned short snum); 1124 1125 /* Keeping track of sockets in use */ 1126 #ifdef CONFIG_PROC_FS 1127 unsigned int inuse_idx; 1128 #endif 1129 1130 bool (*stream_memory_free)(const struct sock *sk, int wake); 1131 bool (*stream_memory_read)(const struct sock *sk); 1132 /* Memory pressure */ 1133 void (*enter_memory_pressure)(struct sock *sk); 1134 void (*leave_memory_pressure)(struct sock *sk); 1135 atomic_long_t *memory_allocated; /* Current allocated memory. */ 1136 struct percpu_counter *sockets_allocated; /* Current number of sockets. */ 1137 /* 1138 * Pressure flag: try to collapse. 1139 * Technical note: it is used by multiple contexts non atomically. 1140 * All the __sk_mem_schedule() is of this nature: accounting 1141 * is strict, actions are advisory and have some latency. 1142 */ 1143 unsigned long *memory_pressure; 1144 long *sysctl_mem; 1145 1146 int *sysctl_wmem; 1147 int *sysctl_rmem; 1148 u32 sysctl_wmem_offset; 1149 u32 sysctl_rmem_offset; 1150 1151 int max_header; 1152 bool no_autobind; 1153 1154 struct kmem_cache *slab; 1155 unsigned int obj_size; 1156 slab_flags_t slab_flags; 1157 unsigned int useroffset; /* Usercopy region offset */ 1158 unsigned int usersize; /* Usercopy region size */ 1159 1160 struct percpu_counter *orphan_count; 1161 1162 struct request_sock_ops *rsk_prot; 1163 struct timewait_sock_ops *twsk_prot; 1164 1165 union { 1166 struct inet_hashinfo *hashinfo; 1167 struct udp_table *udp_table; 1168 struct raw_hashinfo *raw_hash; 1169 struct smc_hashinfo *smc_hash; 1170 } h; 1171 1172 struct module *owner; 1173 1174 char name[32]; 1175 1176 struct list_head node; 1177 #ifdef SOCK_REFCNT_DEBUG 1178 atomic_t socks; 1179 #endif 1180 int (*diag_destroy)(struct sock *sk, int err); 1181 } __randomize_layout; 1182 1183 int proto_register(struct proto *prot, int alloc_slab); 1184 void proto_unregister(struct proto *prot); 1185 int sock_load_diag_module(int family, int protocol); 1186 1187 #ifdef SOCK_REFCNT_DEBUG 1188 static inline void sk_refcnt_debug_inc(struct sock *sk) 1189 { 1190 atomic_inc(&sk->sk_prot->socks); 1191 } 1192 1193 static inline void sk_refcnt_debug_dec(struct sock *sk) 1194 { 1195 atomic_dec(&sk->sk_prot->socks); 1196 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n", 1197 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks)); 1198 } 1199 1200 static inline void sk_refcnt_debug_release(const struct sock *sk) 1201 { 1202 if (refcount_read(&sk->sk_refcnt) != 1) 1203 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n", 1204 sk->sk_prot->name, sk, refcount_read(&sk->sk_refcnt)); 1205 } 1206 #else /* SOCK_REFCNT_DEBUG */ 1207 #define sk_refcnt_debug_inc(sk) do { } while (0) 1208 #define sk_refcnt_debug_dec(sk) do { } while (0) 1209 #define sk_refcnt_debug_release(sk) do { } while (0) 1210 #endif /* SOCK_REFCNT_DEBUG */ 1211 1212 static inline bool __sk_stream_memory_free(const struct sock *sk, int wake) 1213 { 1214 if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf)) 1215 return false; 1216 1217 return sk->sk_prot->stream_memory_free ? 1218 sk->sk_prot->stream_memory_free(sk, wake) : true; 1219 } 1220 1221 static inline bool sk_stream_memory_free(const struct sock *sk) 1222 { 1223 return __sk_stream_memory_free(sk, 0); 1224 } 1225 1226 static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake) 1227 { 1228 return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) && 1229 __sk_stream_memory_free(sk, wake); 1230 } 1231 1232 static inline bool sk_stream_is_writeable(const struct sock *sk) 1233 { 1234 return __sk_stream_is_writeable(sk, 0); 1235 } 1236 1237 static inline int sk_under_cgroup_hierarchy(struct sock *sk, 1238 struct cgroup *ancestor) 1239 { 1240 #ifdef CONFIG_SOCK_CGROUP_DATA 1241 return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data), 1242 ancestor); 1243 #else 1244 return -ENOTSUPP; 1245 #endif 1246 } 1247 1248 static inline bool sk_has_memory_pressure(const struct sock *sk) 1249 { 1250 return sk->sk_prot->memory_pressure != NULL; 1251 } 1252 1253 static inline bool sk_under_memory_pressure(const struct sock *sk) 1254 { 1255 if (!sk->sk_prot->memory_pressure) 1256 return false; 1257 1258 if (mem_cgroup_sockets_enabled && sk->sk_memcg && 1259 mem_cgroup_under_socket_pressure(sk->sk_memcg)) 1260 return true; 1261 1262 return !!*sk->sk_prot->memory_pressure; 1263 } 1264 1265 static inline long 1266 sk_memory_allocated(const struct sock *sk) 1267 { 1268 return atomic_long_read(sk->sk_prot->memory_allocated); 1269 } 1270 1271 static inline long 1272 sk_memory_allocated_add(struct sock *sk, int amt) 1273 { 1274 return atomic_long_add_return(amt, sk->sk_prot->memory_allocated); 1275 } 1276 1277 static inline void 1278 sk_memory_allocated_sub(struct sock *sk, int amt) 1279 { 1280 atomic_long_sub(amt, sk->sk_prot->memory_allocated); 1281 } 1282 1283 static inline void sk_sockets_allocated_dec(struct sock *sk) 1284 { 1285 percpu_counter_dec(sk->sk_prot->sockets_allocated); 1286 } 1287 1288 static inline void sk_sockets_allocated_inc(struct sock *sk) 1289 { 1290 percpu_counter_inc(sk->sk_prot->sockets_allocated); 1291 } 1292 1293 static inline u64 1294 sk_sockets_allocated_read_positive(struct sock *sk) 1295 { 1296 return percpu_counter_read_positive(sk->sk_prot->sockets_allocated); 1297 } 1298 1299 static inline int 1300 proto_sockets_allocated_sum_positive(struct proto *prot) 1301 { 1302 return percpu_counter_sum_positive(prot->sockets_allocated); 1303 } 1304 1305 static inline long 1306 proto_memory_allocated(struct proto *prot) 1307 { 1308 return atomic_long_read(prot->memory_allocated); 1309 } 1310 1311 static inline bool 1312 proto_memory_pressure(struct proto *prot) 1313 { 1314 if (!prot->memory_pressure) 1315 return false; 1316 return !!*prot->memory_pressure; 1317 } 1318 1319 1320 #ifdef CONFIG_PROC_FS 1321 /* Called with local bh disabled */ 1322 void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc); 1323 int sock_prot_inuse_get(struct net *net, struct proto *proto); 1324 int sock_inuse_get(struct net *net); 1325 #else 1326 static inline void sock_prot_inuse_add(struct net *net, struct proto *prot, 1327 int inc) 1328 { 1329 } 1330 #endif 1331 1332 1333 /* With per-bucket locks this operation is not-atomic, so that 1334 * this version is not worse. 1335 */ 1336 static inline int __sk_prot_rehash(struct sock *sk) 1337 { 1338 sk->sk_prot->unhash(sk); 1339 return sk->sk_prot->hash(sk); 1340 } 1341 1342 /* About 10 seconds */ 1343 #define SOCK_DESTROY_TIME (10*HZ) 1344 1345 /* Sockets 0-1023 can't be bound to unless you are superuser */ 1346 #define PROT_SOCK 1024 1347 1348 #define SHUTDOWN_MASK 3 1349 #define RCV_SHUTDOWN 1 1350 #define SEND_SHUTDOWN 2 1351 1352 #define SOCK_SNDBUF_LOCK 1 1353 #define SOCK_RCVBUF_LOCK 2 1354 #define SOCK_BINDADDR_LOCK 4 1355 #define SOCK_BINDPORT_LOCK 8 1356 1357 struct socket_alloc { 1358 struct socket socket; 1359 struct inode vfs_inode; 1360 }; 1361 1362 static inline struct socket *SOCKET_I(struct inode *inode) 1363 { 1364 return &container_of(inode, struct socket_alloc, vfs_inode)->socket; 1365 } 1366 1367 static inline struct inode *SOCK_INODE(struct socket *socket) 1368 { 1369 return &container_of(socket, struct socket_alloc, socket)->vfs_inode; 1370 } 1371 1372 /* 1373 * Functions for memory accounting 1374 */ 1375 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind); 1376 int __sk_mem_schedule(struct sock *sk, int size, int kind); 1377 void __sk_mem_reduce_allocated(struct sock *sk, int amount); 1378 void __sk_mem_reclaim(struct sock *sk, int amount); 1379 1380 /* We used to have PAGE_SIZE here, but systems with 64KB pages 1381 * do not necessarily have 16x time more memory than 4KB ones. 1382 */ 1383 #define SK_MEM_QUANTUM 4096 1384 #define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM) 1385 #define SK_MEM_SEND 0 1386 #define SK_MEM_RECV 1 1387 1388 /* sysctl_mem values are in pages, we convert them in SK_MEM_QUANTUM units */ 1389 static inline long sk_prot_mem_limits(const struct sock *sk, int index) 1390 { 1391 long val = sk->sk_prot->sysctl_mem[index]; 1392 1393 #if PAGE_SIZE > SK_MEM_QUANTUM 1394 val <<= PAGE_SHIFT - SK_MEM_QUANTUM_SHIFT; 1395 #elif PAGE_SIZE < SK_MEM_QUANTUM 1396 val >>= SK_MEM_QUANTUM_SHIFT - PAGE_SHIFT; 1397 #endif 1398 return val; 1399 } 1400 1401 static inline int sk_mem_pages(int amt) 1402 { 1403 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT; 1404 } 1405 1406 static inline bool sk_has_account(struct sock *sk) 1407 { 1408 /* return true if protocol supports memory accounting */ 1409 return !!sk->sk_prot->memory_allocated; 1410 } 1411 1412 static inline bool sk_wmem_schedule(struct sock *sk, int size) 1413 { 1414 if (!sk_has_account(sk)) 1415 return true; 1416 return size <= sk->sk_forward_alloc || 1417 __sk_mem_schedule(sk, size, SK_MEM_SEND); 1418 } 1419 1420 static inline bool 1421 sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size) 1422 { 1423 if (!sk_has_account(sk)) 1424 return true; 1425 return size<= sk->sk_forward_alloc || 1426 __sk_mem_schedule(sk, size, SK_MEM_RECV) || 1427 skb_pfmemalloc(skb); 1428 } 1429 1430 static inline void sk_mem_reclaim(struct sock *sk) 1431 { 1432 if (!sk_has_account(sk)) 1433 return; 1434 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM) 1435 __sk_mem_reclaim(sk, sk->sk_forward_alloc); 1436 } 1437 1438 static inline void sk_mem_reclaim_partial(struct sock *sk) 1439 { 1440 if (!sk_has_account(sk)) 1441 return; 1442 if (sk->sk_forward_alloc > SK_MEM_QUANTUM) 1443 __sk_mem_reclaim(sk, sk->sk_forward_alloc - 1); 1444 } 1445 1446 static inline void sk_mem_charge(struct sock *sk, int size) 1447 { 1448 if (!sk_has_account(sk)) 1449 return; 1450 sk->sk_forward_alloc -= size; 1451 } 1452 1453 static inline void sk_mem_uncharge(struct sock *sk, int size) 1454 { 1455 if (!sk_has_account(sk)) 1456 return; 1457 sk->sk_forward_alloc += size; 1458 1459 /* Avoid a possible overflow. 1460 * TCP send queues can make this happen, if sk_mem_reclaim() 1461 * is not called and more than 2 GBytes are released at once. 1462 * 1463 * If we reach 2 MBytes, reclaim 1 MBytes right now, there is 1464 * no need to hold that much forward allocation anyway. 1465 */ 1466 if (unlikely(sk->sk_forward_alloc >= 1 << 21)) 1467 __sk_mem_reclaim(sk, 1 << 20); 1468 } 1469 1470 DECLARE_STATIC_KEY_FALSE(tcp_tx_skb_cache_key); 1471 static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb) 1472 { 1473 sock_set_flag(sk, SOCK_QUEUE_SHRUNK); 1474 sk_wmem_queued_add(sk, -skb->truesize); 1475 sk_mem_uncharge(sk, skb->truesize); 1476 if (static_branch_unlikely(&tcp_tx_skb_cache_key) && 1477 !sk->sk_tx_skb_cache && !skb_cloned(skb)) { 1478 skb_zcopy_clear(skb, true); 1479 sk->sk_tx_skb_cache = skb; 1480 return; 1481 } 1482 __kfree_skb(skb); 1483 } 1484 1485 static inline void sock_release_ownership(struct sock *sk) 1486 { 1487 if (sk->sk_lock.owned) { 1488 sk->sk_lock.owned = 0; 1489 1490 /* The sk_lock has mutex_unlock() semantics: */ 1491 mutex_release(&sk->sk_lock.dep_map, _RET_IP_); 1492 } 1493 } 1494 1495 /* 1496 * Macro so as to not evaluate some arguments when 1497 * lockdep is not enabled. 1498 * 1499 * Mark both the sk_lock and the sk_lock.slock as a 1500 * per-address-family lock class. 1501 */ 1502 #define sock_lock_init_class_and_name(sk, sname, skey, name, key) \ 1503 do { \ 1504 sk->sk_lock.owned = 0; \ 1505 init_waitqueue_head(&sk->sk_lock.wq); \ 1506 spin_lock_init(&(sk)->sk_lock.slock); \ 1507 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \ 1508 sizeof((sk)->sk_lock)); \ 1509 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \ 1510 (skey), (sname)); \ 1511 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \ 1512 } while (0) 1513 1514 #ifdef CONFIG_LOCKDEP 1515 static inline bool lockdep_sock_is_held(const struct sock *sk) 1516 { 1517 return lockdep_is_held(&sk->sk_lock) || 1518 lockdep_is_held(&sk->sk_lock.slock); 1519 } 1520 #endif 1521 1522 void lock_sock_nested(struct sock *sk, int subclass); 1523 1524 static inline void lock_sock(struct sock *sk) 1525 { 1526 lock_sock_nested(sk, 0); 1527 } 1528 1529 void __release_sock(struct sock *sk); 1530 void release_sock(struct sock *sk); 1531 1532 /* BH context may only use the following locking interface. */ 1533 #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock)) 1534 #define bh_lock_sock_nested(__sk) \ 1535 spin_lock_nested(&((__sk)->sk_lock.slock), \ 1536 SINGLE_DEPTH_NESTING) 1537 #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock)) 1538 1539 bool lock_sock_fast(struct sock *sk); 1540 /** 1541 * unlock_sock_fast - complement of lock_sock_fast 1542 * @sk: socket 1543 * @slow: slow mode 1544 * 1545 * fast unlock socket for user context. 1546 * If slow mode is on, we call regular release_sock() 1547 */ 1548 static inline void unlock_sock_fast(struct sock *sk, bool slow) 1549 { 1550 if (slow) 1551 release_sock(sk); 1552 else 1553 spin_unlock_bh(&sk->sk_lock.slock); 1554 } 1555 1556 /* Used by processes to "lock" a socket state, so that 1557 * interrupts and bottom half handlers won't change it 1558 * from under us. It essentially blocks any incoming 1559 * packets, so that we won't get any new data or any 1560 * packets that change the state of the socket. 1561 * 1562 * While locked, BH processing will add new packets to 1563 * the backlog queue. This queue is processed by the 1564 * owner of the socket lock right before it is released. 1565 * 1566 * Since ~2.3.5 it is also exclusive sleep lock serializing 1567 * accesses from user process context. 1568 */ 1569 1570 static inline void sock_owned_by_me(const struct sock *sk) 1571 { 1572 #ifdef CONFIG_LOCKDEP 1573 WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks); 1574 #endif 1575 } 1576 1577 static inline bool sock_owned_by_user(const struct sock *sk) 1578 { 1579 sock_owned_by_me(sk); 1580 return sk->sk_lock.owned; 1581 } 1582 1583 static inline bool sock_owned_by_user_nocheck(const struct sock *sk) 1584 { 1585 return sk->sk_lock.owned; 1586 } 1587 1588 /* no reclassification while locks are held */ 1589 static inline bool sock_allow_reclassification(const struct sock *csk) 1590 { 1591 struct sock *sk = (struct sock *)csk; 1592 1593 return !sk->sk_lock.owned && !spin_is_locked(&sk->sk_lock.slock); 1594 } 1595 1596 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 1597 struct proto *prot, int kern); 1598 void sk_free(struct sock *sk); 1599 void sk_destruct(struct sock *sk); 1600 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority); 1601 void sk_free_unlock_clone(struct sock *sk); 1602 1603 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 1604 gfp_t priority); 1605 void __sock_wfree(struct sk_buff *skb); 1606 void sock_wfree(struct sk_buff *skb); 1607 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size, 1608 gfp_t priority); 1609 void skb_orphan_partial(struct sk_buff *skb); 1610 void sock_rfree(struct sk_buff *skb); 1611 void sock_efree(struct sk_buff *skb); 1612 #ifdef CONFIG_INET 1613 void sock_edemux(struct sk_buff *skb); 1614 #else 1615 #define sock_edemux sock_efree 1616 #endif 1617 1618 int sock_setsockopt(struct socket *sock, int level, int op, 1619 char __user *optval, unsigned int optlen); 1620 1621 int sock_getsockopt(struct socket *sock, int level, int op, 1622 char __user *optval, int __user *optlen); 1623 int sock_gettstamp(struct socket *sock, void __user *userstamp, 1624 bool timeval, bool time32); 1625 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, 1626 int noblock, int *errcode); 1627 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 1628 unsigned long data_len, int noblock, 1629 int *errcode, int max_page_order); 1630 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority); 1631 void sock_kfree_s(struct sock *sk, void *mem, int size); 1632 void sock_kzfree_s(struct sock *sk, void *mem, int size); 1633 void sk_send_sigurg(struct sock *sk); 1634 1635 struct sockcm_cookie { 1636 u64 transmit_time; 1637 u32 mark; 1638 u16 tsflags; 1639 }; 1640 1641 static inline void sockcm_init(struct sockcm_cookie *sockc, 1642 const struct sock *sk) 1643 { 1644 *sockc = (struct sockcm_cookie) { .tsflags = sk->sk_tsflags }; 1645 } 1646 1647 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg, 1648 struct sockcm_cookie *sockc); 1649 int sock_cmsg_send(struct sock *sk, struct msghdr *msg, 1650 struct sockcm_cookie *sockc); 1651 1652 /* 1653 * Functions to fill in entries in struct proto_ops when a protocol 1654 * does not implement a particular function. 1655 */ 1656 int sock_no_bind(struct socket *, struct sockaddr *, int); 1657 int sock_no_connect(struct socket *, struct sockaddr *, int, int); 1658 int sock_no_socketpair(struct socket *, struct socket *); 1659 int sock_no_accept(struct socket *, struct socket *, int, bool); 1660 int sock_no_getname(struct socket *, struct sockaddr *, int); 1661 int sock_no_ioctl(struct socket *, unsigned int, unsigned long); 1662 int sock_no_listen(struct socket *, int); 1663 int sock_no_shutdown(struct socket *, int); 1664 int sock_no_getsockopt(struct socket *, int , int, char __user *, int __user *); 1665 int sock_no_setsockopt(struct socket *, int, int, char __user *, unsigned int); 1666 int sock_no_sendmsg(struct socket *, struct msghdr *, size_t); 1667 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len); 1668 int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int); 1669 int sock_no_mmap(struct file *file, struct socket *sock, 1670 struct vm_area_struct *vma); 1671 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, 1672 size_t size, int flags); 1673 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page, 1674 int offset, size_t size, int flags); 1675 1676 /* 1677 * Functions to fill in entries in struct proto_ops when a protocol 1678 * uses the inet style. 1679 */ 1680 int sock_common_getsockopt(struct socket *sock, int level, int optname, 1681 char __user *optval, int __user *optlen); 1682 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 1683 int flags); 1684 int sock_common_setsockopt(struct socket *sock, int level, int optname, 1685 char __user *optval, unsigned int optlen); 1686 int compat_sock_common_getsockopt(struct socket *sock, int level, 1687 int optname, char __user *optval, int __user *optlen); 1688 int compat_sock_common_setsockopt(struct socket *sock, int level, 1689 int optname, char __user *optval, unsigned int optlen); 1690 1691 void sk_common_release(struct sock *sk); 1692 1693 /* 1694 * Default socket callbacks and setup code 1695 */ 1696 1697 /* Initialise core socket variables */ 1698 void sock_init_data(struct socket *sock, struct sock *sk); 1699 1700 /* 1701 * Socket reference counting postulates. 1702 * 1703 * * Each user of socket SHOULD hold a reference count. 1704 * * Each access point to socket (an hash table bucket, reference from a list, 1705 * running timer, skb in flight MUST hold a reference count. 1706 * * When reference count hits 0, it means it will never increase back. 1707 * * When reference count hits 0, it means that no references from 1708 * outside exist to this socket and current process on current CPU 1709 * is last user and may/should destroy this socket. 1710 * * sk_free is called from any context: process, BH, IRQ. When 1711 * it is called, socket has no references from outside -> sk_free 1712 * may release descendant resources allocated by the socket, but 1713 * to the time when it is called, socket is NOT referenced by any 1714 * hash tables, lists etc. 1715 * * Packets, delivered from outside (from network or from another process) 1716 * and enqueued on receive/error queues SHOULD NOT grab reference count, 1717 * when they sit in queue. Otherwise, packets will leak to hole, when 1718 * socket is looked up by one cpu and unhasing is made by another CPU. 1719 * It is true for udp/raw, netlink (leak to receive and error queues), tcp 1720 * (leak to backlog). Packet socket does all the processing inside 1721 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets 1722 * use separate SMP lock, so that they are prone too. 1723 */ 1724 1725 /* Ungrab socket and destroy it, if it was the last reference. */ 1726 static inline void sock_put(struct sock *sk) 1727 { 1728 if (refcount_dec_and_test(&sk->sk_refcnt)) 1729 sk_free(sk); 1730 } 1731 /* Generic version of sock_put(), dealing with all sockets 1732 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...) 1733 */ 1734 void sock_gen_put(struct sock *sk); 1735 1736 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested, 1737 unsigned int trim_cap, bool refcounted); 1738 static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb, 1739 const int nested) 1740 { 1741 return __sk_receive_skb(sk, skb, nested, 1, true); 1742 } 1743 1744 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue) 1745 { 1746 /* sk_tx_queue_mapping accept only upto a 16-bit value */ 1747 if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX)) 1748 return; 1749 sk->sk_tx_queue_mapping = tx_queue; 1750 } 1751 1752 #define NO_QUEUE_MAPPING USHRT_MAX 1753 1754 static inline void sk_tx_queue_clear(struct sock *sk) 1755 { 1756 sk->sk_tx_queue_mapping = NO_QUEUE_MAPPING; 1757 } 1758 1759 static inline int sk_tx_queue_get(const struct sock *sk) 1760 { 1761 if (sk && sk->sk_tx_queue_mapping != NO_QUEUE_MAPPING) 1762 return sk->sk_tx_queue_mapping; 1763 1764 return -1; 1765 } 1766 1767 static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb) 1768 { 1769 #ifdef CONFIG_XPS 1770 if (skb_rx_queue_recorded(skb)) { 1771 u16 rx_queue = skb_get_rx_queue(skb); 1772 1773 if (WARN_ON_ONCE(rx_queue == NO_QUEUE_MAPPING)) 1774 return; 1775 1776 sk->sk_rx_queue_mapping = rx_queue; 1777 } 1778 #endif 1779 } 1780 1781 static inline void sk_rx_queue_clear(struct sock *sk) 1782 { 1783 #ifdef CONFIG_XPS 1784 sk->sk_rx_queue_mapping = NO_QUEUE_MAPPING; 1785 #endif 1786 } 1787 1788 #ifdef CONFIG_XPS 1789 static inline int sk_rx_queue_get(const struct sock *sk) 1790 { 1791 if (sk && sk->sk_rx_queue_mapping != NO_QUEUE_MAPPING) 1792 return sk->sk_rx_queue_mapping; 1793 1794 return -1; 1795 } 1796 #endif 1797 1798 static inline void sk_set_socket(struct sock *sk, struct socket *sock) 1799 { 1800 sk_tx_queue_clear(sk); 1801 sk->sk_socket = sock; 1802 } 1803 1804 static inline wait_queue_head_t *sk_sleep(struct sock *sk) 1805 { 1806 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0); 1807 return &rcu_dereference_raw(sk->sk_wq)->wait; 1808 } 1809 /* Detach socket from process context. 1810 * Announce socket dead, detach it from wait queue and inode. 1811 * Note that parent inode held reference count on this struct sock, 1812 * we do not release it in this function, because protocol 1813 * probably wants some additional cleanups or even continuing 1814 * to work with this socket (TCP). 1815 */ 1816 static inline void sock_orphan(struct sock *sk) 1817 { 1818 write_lock_bh(&sk->sk_callback_lock); 1819 sock_set_flag(sk, SOCK_DEAD); 1820 sk_set_socket(sk, NULL); 1821 sk->sk_wq = NULL; 1822 write_unlock_bh(&sk->sk_callback_lock); 1823 } 1824 1825 static inline void sock_graft(struct sock *sk, struct socket *parent) 1826 { 1827 WARN_ON(parent->sk); 1828 write_lock_bh(&sk->sk_callback_lock); 1829 rcu_assign_pointer(sk->sk_wq, &parent->wq); 1830 parent->sk = sk; 1831 sk_set_socket(sk, parent); 1832 sk->sk_uid = SOCK_INODE(parent)->i_uid; 1833 security_sock_graft(sk, parent); 1834 write_unlock_bh(&sk->sk_callback_lock); 1835 } 1836 1837 kuid_t sock_i_uid(struct sock *sk); 1838 unsigned long sock_i_ino(struct sock *sk); 1839 1840 static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk) 1841 { 1842 return sk ? sk->sk_uid : make_kuid(net->user_ns, 0); 1843 } 1844 1845 static inline u32 net_tx_rndhash(void) 1846 { 1847 u32 v = prandom_u32(); 1848 1849 return v ?: 1; 1850 } 1851 1852 static inline void sk_set_txhash(struct sock *sk) 1853 { 1854 sk->sk_txhash = net_tx_rndhash(); 1855 } 1856 1857 static inline void sk_rethink_txhash(struct sock *sk) 1858 { 1859 if (sk->sk_txhash) 1860 sk_set_txhash(sk); 1861 } 1862 1863 static inline struct dst_entry * 1864 __sk_dst_get(struct sock *sk) 1865 { 1866 return rcu_dereference_check(sk->sk_dst_cache, 1867 lockdep_sock_is_held(sk)); 1868 } 1869 1870 static inline struct dst_entry * 1871 sk_dst_get(struct sock *sk) 1872 { 1873 struct dst_entry *dst; 1874 1875 rcu_read_lock(); 1876 dst = rcu_dereference(sk->sk_dst_cache); 1877 if (dst && !atomic_inc_not_zero(&dst->__refcnt)) 1878 dst = NULL; 1879 rcu_read_unlock(); 1880 return dst; 1881 } 1882 1883 static inline void dst_negative_advice(struct sock *sk) 1884 { 1885 struct dst_entry *ndst, *dst = __sk_dst_get(sk); 1886 1887 sk_rethink_txhash(sk); 1888 1889 if (dst && dst->ops->negative_advice) { 1890 ndst = dst->ops->negative_advice(dst); 1891 1892 if (ndst != dst) { 1893 rcu_assign_pointer(sk->sk_dst_cache, ndst); 1894 sk_tx_queue_clear(sk); 1895 sk->sk_dst_pending_confirm = 0; 1896 } 1897 } 1898 } 1899 1900 static inline void 1901 __sk_dst_set(struct sock *sk, struct dst_entry *dst) 1902 { 1903 struct dst_entry *old_dst; 1904 1905 sk_tx_queue_clear(sk); 1906 sk->sk_dst_pending_confirm = 0; 1907 old_dst = rcu_dereference_protected(sk->sk_dst_cache, 1908 lockdep_sock_is_held(sk)); 1909 rcu_assign_pointer(sk->sk_dst_cache, dst); 1910 dst_release(old_dst); 1911 } 1912 1913 static inline void 1914 sk_dst_set(struct sock *sk, struct dst_entry *dst) 1915 { 1916 struct dst_entry *old_dst; 1917 1918 sk_tx_queue_clear(sk); 1919 sk->sk_dst_pending_confirm = 0; 1920 old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst); 1921 dst_release(old_dst); 1922 } 1923 1924 static inline void 1925 __sk_dst_reset(struct sock *sk) 1926 { 1927 __sk_dst_set(sk, NULL); 1928 } 1929 1930 static inline void 1931 sk_dst_reset(struct sock *sk) 1932 { 1933 sk_dst_set(sk, NULL); 1934 } 1935 1936 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie); 1937 1938 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie); 1939 1940 static inline void sk_dst_confirm(struct sock *sk) 1941 { 1942 if (!READ_ONCE(sk->sk_dst_pending_confirm)) 1943 WRITE_ONCE(sk->sk_dst_pending_confirm, 1); 1944 } 1945 1946 static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n) 1947 { 1948 if (skb_get_dst_pending_confirm(skb)) { 1949 struct sock *sk = skb->sk; 1950 unsigned long now = jiffies; 1951 1952 /* avoid dirtying neighbour */ 1953 if (READ_ONCE(n->confirmed) != now) 1954 WRITE_ONCE(n->confirmed, now); 1955 if (sk && READ_ONCE(sk->sk_dst_pending_confirm)) 1956 WRITE_ONCE(sk->sk_dst_pending_confirm, 0); 1957 } 1958 } 1959 1960 bool sk_mc_loop(struct sock *sk); 1961 1962 static inline bool sk_can_gso(const struct sock *sk) 1963 { 1964 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type); 1965 } 1966 1967 void sk_setup_caps(struct sock *sk, struct dst_entry *dst); 1968 1969 static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags) 1970 { 1971 sk->sk_route_nocaps |= flags; 1972 sk->sk_route_caps &= ~flags; 1973 } 1974 1975 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb, 1976 struct iov_iter *from, char *to, 1977 int copy, int offset) 1978 { 1979 if (skb->ip_summed == CHECKSUM_NONE) { 1980 __wsum csum = 0; 1981 if (!csum_and_copy_from_iter_full(to, copy, &csum, from)) 1982 return -EFAULT; 1983 skb->csum = csum_block_add(skb->csum, csum, offset); 1984 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) { 1985 if (!copy_from_iter_full_nocache(to, copy, from)) 1986 return -EFAULT; 1987 } else if (!copy_from_iter_full(to, copy, from)) 1988 return -EFAULT; 1989 1990 return 0; 1991 } 1992 1993 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb, 1994 struct iov_iter *from, int copy) 1995 { 1996 int err, offset = skb->len; 1997 1998 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy), 1999 copy, offset); 2000 if (err) 2001 __skb_trim(skb, offset); 2002 2003 return err; 2004 } 2005 2006 static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from, 2007 struct sk_buff *skb, 2008 struct page *page, 2009 int off, int copy) 2010 { 2011 int err; 2012 2013 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off, 2014 copy, skb->len); 2015 if (err) 2016 return err; 2017 2018 skb->len += copy; 2019 skb->data_len += copy; 2020 skb->truesize += copy; 2021 sk_wmem_queued_add(sk, copy); 2022 sk_mem_charge(sk, copy); 2023 return 0; 2024 } 2025 2026 /** 2027 * sk_wmem_alloc_get - returns write allocations 2028 * @sk: socket 2029 * 2030 * Returns sk_wmem_alloc minus initial offset of one 2031 */ 2032 static inline int sk_wmem_alloc_get(const struct sock *sk) 2033 { 2034 return refcount_read(&sk->sk_wmem_alloc) - 1; 2035 } 2036 2037 /** 2038 * sk_rmem_alloc_get - returns read allocations 2039 * @sk: socket 2040 * 2041 * Returns sk_rmem_alloc 2042 */ 2043 static inline int sk_rmem_alloc_get(const struct sock *sk) 2044 { 2045 return atomic_read(&sk->sk_rmem_alloc); 2046 } 2047 2048 /** 2049 * sk_has_allocations - check if allocations are outstanding 2050 * @sk: socket 2051 * 2052 * Returns true if socket has write or read allocations 2053 */ 2054 static inline bool sk_has_allocations(const struct sock *sk) 2055 { 2056 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk); 2057 } 2058 2059 /** 2060 * skwq_has_sleeper - check if there are any waiting processes 2061 * @wq: struct socket_wq 2062 * 2063 * Returns true if socket_wq has waiting processes 2064 * 2065 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory 2066 * barrier call. They were added due to the race found within the tcp code. 2067 * 2068 * Consider following tcp code paths:: 2069 * 2070 * CPU1 CPU2 2071 * sys_select receive packet 2072 * ... ... 2073 * __add_wait_queue update tp->rcv_nxt 2074 * ... ... 2075 * tp->rcv_nxt check sock_def_readable 2076 * ... { 2077 * schedule rcu_read_lock(); 2078 * wq = rcu_dereference(sk->sk_wq); 2079 * if (wq && waitqueue_active(&wq->wait)) 2080 * wake_up_interruptible(&wq->wait) 2081 * ... 2082 * } 2083 * 2084 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay 2085 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1 2086 * could then endup calling schedule and sleep forever if there are no more 2087 * data on the socket. 2088 * 2089 */ 2090 static inline bool skwq_has_sleeper(struct socket_wq *wq) 2091 { 2092 return wq && wq_has_sleeper(&wq->wait); 2093 } 2094 2095 /** 2096 * sock_poll_wait - place memory barrier behind the poll_wait call. 2097 * @filp: file 2098 * @sock: socket to wait on 2099 * @p: poll_table 2100 * 2101 * See the comments in the wq_has_sleeper function. 2102 */ 2103 static inline void sock_poll_wait(struct file *filp, struct socket *sock, 2104 poll_table *p) 2105 { 2106 if (!poll_does_not_wait(p)) { 2107 poll_wait(filp, &sock->wq.wait, p); 2108 /* We need to be sure we are in sync with the 2109 * socket flags modification. 2110 * 2111 * This memory barrier is paired in the wq_has_sleeper. 2112 */ 2113 smp_mb(); 2114 } 2115 } 2116 2117 static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk) 2118 { 2119 if (sk->sk_txhash) { 2120 skb->l4_hash = 1; 2121 skb->hash = sk->sk_txhash; 2122 } 2123 } 2124 2125 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk); 2126 2127 /* 2128 * Queue a received datagram if it will fit. Stream and sequenced 2129 * protocols can't normally use this as they need to fit buffers in 2130 * and play with them. 2131 * 2132 * Inlined as it's very short and called for pretty much every 2133 * packet ever received. 2134 */ 2135 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk) 2136 { 2137 skb_orphan(skb); 2138 skb->sk = sk; 2139 skb->destructor = sock_rfree; 2140 atomic_add(skb->truesize, &sk->sk_rmem_alloc); 2141 sk_mem_charge(sk, skb->truesize); 2142 } 2143 2144 void sk_reset_timer(struct sock *sk, struct timer_list *timer, 2145 unsigned long expires); 2146 2147 void sk_stop_timer(struct sock *sk, struct timer_list *timer); 2148 2149 int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue, 2150 struct sk_buff *skb, unsigned int flags, 2151 void (*destructor)(struct sock *sk, 2152 struct sk_buff *skb)); 2153 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); 2154 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); 2155 2156 int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb); 2157 struct sk_buff *sock_dequeue_err_skb(struct sock *sk); 2158 2159 /* 2160 * Recover an error report and clear atomically 2161 */ 2162 2163 static inline int sock_error(struct sock *sk) 2164 { 2165 int err; 2166 if (likely(!sk->sk_err)) 2167 return 0; 2168 err = xchg(&sk->sk_err, 0); 2169 return -err; 2170 } 2171 2172 static inline unsigned long sock_wspace(struct sock *sk) 2173 { 2174 int amt = 0; 2175 2176 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { 2177 amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc); 2178 if (amt < 0) 2179 amt = 0; 2180 } 2181 return amt; 2182 } 2183 2184 /* Note: 2185 * We use sk->sk_wq_raw, from contexts knowing this 2186 * pointer is not NULL and cannot disappear/change. 2187 */ 2188 static inline void sk_set_bit(int nr, struct sock *sk) 2189 { 2190 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) && 2191 !sock_flag(sk, SOCK_FASYNC)) 2192 return; 2193 2194 set_bit(nr, &sk->sk_wq_raw->flags); 2195 } 2196 2197 static inline void sk_clear_bit(int nr, struct sock *sk) 2198 { 2199 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) && 2200 !sock_flag(sk, SOCK_FASYNC)) 2201 return; 2202 2203 clear_bit(nr, &sk->sk_wq_raw->flags); 2204 } 2205 2206 static inline void sk_wake_async(const struct sock *sk, int how, int band) 2207 { 2208 if (sock_flag(sk, SOCK_FASYNC)) { 2209 rcu_read_lock(); 2210 sock_wake_async(rcu_dereference(sk->sk_wq), how, band); 2211 rcu_read_unlock(); 2212 } 2213 } 2214 2215 /* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might 2216 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak. 2217 * Note: for send buffers, TCP works better if we can build two skbs at 2218 * minimum. 2219 */ 2220 #define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff))) 2221 2222 #define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2) 2223 #define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE 2224 2225 static inline void sk_stream_moderate_sndbuf(struct sock *sk) 2226 { 2227 u32 val; 2228 2229 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) 2230 return; 2231 2232 val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1); 2233 2234 WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF)); 2235 } 2236 2237 struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp, 2238 bool force_schedule); 2239 2240 /** 2241 * sk_page_frag - return an appropriate page_frag 2242 * @sk: socket 2243 * 2244 * Use the per task page_frag instead of the per socket one for 2245 * optimization when we know that we're in the normal context and owns 2246 * everything that's associated with %current. 2247 * 2248 * gfpflags_allow_blocking() isn't enough here as direct reclaim may nest 2249 * inside other socket operations and end up recursing into sk_page_frag() 2250 * while it's already in use. 2251 */ 2252 static inline struct page_frag *sk_page_frag(struct sock *sk) 2253 { 2254 if (gfpflags_normal_context(sk->sk_allocation)) 2255 return ¤t->task_frag; 2256 2257 return &sk->sk_frag; 2258 } 2259 2260 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag); 2261 2262 /* 2263 * Default write policy as shown to user space via poll/select/SIGIO 2264 */ 2265 static inline bool sock_writeable(const struct sock *sk) 2266 { 2267 return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1); 2268 } 2269 2270 static inline gfp_t gfp_any(void) 2271 { 2272 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL; 2273 } 2274 2275 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock) 2276 { 2277 return noblock ? 0 : sk->sk_rcvtimeo; 2278 } 2279 2280 static inline long sock_sndtimeo(const struct sock *sk, bool noblock) 2281 { 2282 return noblock ? 0 : sk->sk_sndtimeo; 2283 } 2284 2285 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len) 2286 { 2287 int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len); 2288 2289 return v ?: 1; 2290 } 2291 2292 /* Alas, with timeout socket operations are not restartable. 2293 * Compare this to poll(). 2294 */ 2295 static inline int sock_intr_errno(long timeo) 2296 { 2297 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR; 2298 } 2299 2300 struct sock_skb_cb { 2301 u32 dropcount; 2302 }; 2303 2304 /* Store sock_skb_cb at the end of skb->cb[] so protocol families 2305 * using skb->cb[] would keep using it directly and utilize its 2306 * alignement guarantee. 2307 */ 2308 #define SOCK_SKB_CB_OFFSET ((FIELD_SIZEOF(struct sk_buff, cb) - \ 2309 sizeof(struct sock_skb_cb))) 2310 2311 #define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \ 2312 SOCK_SKB_CB_OFFSET)) 2313 2314 #define sock_skb_cb_check_size(size) \ 2315 BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET) 2316 2317 static inline void 2318 sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb) 2319 { 2320 SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ? 2321 atomic_read(&sk->sk_drops) : 0; 2322 } 2323 2324 static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb) 2325 { 2326 int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs); 2327 2328 atomic_add(segs, &sk->sk_drops); 2329 } 2330 2331 static inline ktime_t sock_read_timestamp(struct sock *sk) 2332 { 2333 #if BITS_PER_LONG==32 2334 unsigned int seq; 2335 ktime_t kt; 2336 2337 do { 2338 seq = read_seqbegin(&sk->sk_stamp_seq); 2339 kt = sk->sk_stamp; 2340 } while (read_seqretry(&sk->sk_stamp_seq, seq)); 2341 2342 return kt; 2343 #else 2344 return READ_ONCE(sk->sk_stamp); 2345 #endif 2346 } 2347 2348 static inline void sock_write_timestamp(struct sock *sk, ktime_t kt) 2349 { 2350 #if BITS_PER_LONG==32 2351 write_seqlock(&sk->sk_stamp_seq); 2352 sk->sk_stamp = kt; 2353 write_sequnlock(&sk->sk_stamp_seq); 2354 #else 2355 WRITE_ONCE(sk->sk_stamp, kt); 2356 #endif 2357 } 2358 2359 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk, 2360 struct sk_buff *skb); 2361 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk, 2362 struct sk_buff *skb); 2363 2364 static inline void 2365 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb) 2366 { 2367 ktime_t kt = skb->tstamp; 2368 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb); 2369 2370 /* 2371 * generate control messages if 2372 * - receive time stamping in software requested 2373 * - software time stamp available and wanted 2374 * - hardware time stamps available and wanted 2375 */ 2376 if (sock_flag(sk, SOCK_RCVTSTAMP) || 2377 (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) || 2378 (kt && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) || 2379 (hwtstamps->hwtstamp && 2380 (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE))) 2381 __sock_recv_timestamp(msg, sk, skb); 2382 else 2383 sock_write_timestamp(sk, kt); 2384 2385 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid) 2386 __sock_recv_wifi_status(msg, sk, skb); 2387 } 2388 2389 void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk, 2390 struct sk_buff *skb); 2391 2392 #define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC) 2393 static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk, 2394 struct sk_buff *skb) 2395 { 2396 #define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \ 2397 (1UL << SOCK_RCVTSTAMP)) 2398 #define TSFLAGS_ANY (SOF_TIMESTAMPING_SOFTWARE | \ 2399 SOF_TIMESTAMPING_RAW_HARDWARE) 2400 2401 if (sk->sk_flags & FLAGS_TS_OR_DROPS || sk->sk_tsflags & TSFLAGS_ANY) 2402 __sock_recv_ts_and_drops(msg, sk, skb); 2403 else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP))) 2404 sock_write_timestamp(sk, skb->tstamp); 2405 else if (unlikely(sk->sk_stamp == SK_DEFAULT_STAMP)) 2406 sock_write_timestamp(sk, 0); 2407 } 2408 2409 void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags); 2410 2411 /** 2412 * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped 2413 * @sk: socket sending this packet 2414 * @tsflags: timestamping flags to use 2415 * @tx_flags: completed with instructions for time stamping 2416 * @tskey: filled in with next sk_tskey (not for TCP, which uses seqno) 2417 * 2418 * Note: callers should take care of initial ``*tx_flags`` value (usually 0) 2419 */ 2420 static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags, 2421 __u8 *tx_flags, __u32 *tskey) 2422 { 2423 if (unlikely(tsflags)) { 2424 __sock_tx_timestamp(tsflags, tx_flags); 2425 if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey && 2426 tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK) 2427 *tskey = sk->sk_tskey++; 2428 } 2429 if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS))) 2430 *tx_flags |= SKBTX_WIFI_STATUS; 2431 } 2432 2433 static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags, 2434 __u8 *tx_flags) 2435 { 2436 _sock_tx_timestamp(sk, tsflags, tx_flags, NULL); 2437 } 2438 2439 static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags) 2440 { 2441 _sock_tx_timestamp(skb->sk, tsflags, &skb_shinfo(skb)->tx_flags, 2442 &skb_shinfo(skb)->tskey); 2443 } 2444 2445 /** 2446 * sk_eat_skb - Release a skb if it is no longer needed 2447 * @sk: socket to eat this skb from 2448 * @skb: socket buffer to eat 2449 * 2450 * This routine must be called with interrupts disabled or with the socket 2451 * locked so that the sk_buff queue operation is ok. 2452 */ 2453 DECLARE_STATIC_KEY_FALSE(tcp_rx_skb_cache_key); 2454 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb) 2455 { 2456 __skb_unlink(skb, &sk->sk_receive_queue); 2457 if (static_branch_unlikely(&tcp_rx_skb_cache_key) && 2458 !sk->sk_rx_skb_cache) { 2459 sk->sk_rx_skb_cache = skb; 2460 skb_orphan(skb); 2461 return; 2462 } 2463 __kfree_skb(skb); 2464 } 2465 2466 static inline 2467 struct net *sock_net(const struct sock *sk) 2468 { 2469 return read_pnet(&sk->sk_net); 2470 } 2471 2472 static inline 2473 void sock_net_set(struct sock *sk, struct net *net) 2474 { 2475 write_pnet(&sk->sk_net, net); 2476 } 2477 2478 static inline struct sock *skb_steal_sock(struct sk_buff *skb) 2479 { 2480 if (skb->sk) { 2481 struct sock *sk = skb->sk; 2482 2483 skb->destructor = NULL; 2484 skb->sk = NULL; 2485 return sk; 2486 } 2487 return NULL; 2488 } 2489 2490 /* This helper checks if a socket is a full socket, 2491 * ie _not_ a timewait or request socket. 2492 */ 2493 static inline bool sk_fullsock(const struct sock *sk) 2494 { 2495 return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV); 2496 } 2497 2498 /* Checks if this SKB belongs to an HW offloaded socket 2499 * and whether any SW fallbacks are required based on dev. 2500 * Check decrypted mark in case skb_orphan() cleared socket. 2501 */ 2502 static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb, 2503 struct net_device *dev) 2504 { 2505 #ifdef CONFIG_SOCK_VALIDATE_XMIT 2506 struct sock *sk = skb->sk; 2507 2508 if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) { 2509 skb = sk->sk_validate_xmit_skb(sk, dev, skb); 2510 #ifdef CONFIG_TLS_DEVICE 2511 } else if (unlikely(skb->decrypted)) { 2512 pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n"); 2513 kfree_skb(skb); 2514 skb = NULL; 2515 #endif 2516 } 2517 #endif 2518 2519 return skb; 2520 } 2521 2522 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV 2523 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE) 2524 */ 2525 static inline bool sk_listener(const struct sock *sk) 2526 { 2527 return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV); 2528 } 2529 2530 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag); 2531 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level, 2532 int type); 2533 2534 bool sk_ns_capable(const struct sock *sk, 2535 struct user_namespace *user_ns, int cap); 2536 bool sk_capable(const struct sock *sk, int cap); 2537 bool sk_net_capable(const struct sock *sk, int cap); 2538 2539 void sk_get_meminfo(const struct sock *sk, u32 *meminfo); 2540 2541 /* Take into consideration the size of the struct sk_buff overhead in the 2542 * determination of these values, since that is non-constant across 2543 * platforms. This makes socket queueing behavior and performance 2544 * not depend upon such differences. 2545 */ 2546 #define _SK_MEM_PACKETS 256 2547 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256) 2548 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 2549 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 2550 2551 extern __u32 sysctl_wmem_max; 2552 extern __u32 sysctl_rmem_max; 2553 2554 extern int sysctl_tstamp_allow_data; 2555 extern int sysctl_optmem_max; 2556 2557 extern __u32 sysctl_wmem_default; 2558 extern __u32 sysctl_rmem_default; 2559 2560 DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key); 2561 2562 static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto) 2563 { 2564 /* Does this proto have per netns sysctl_wmem ? */ 2565 if (proto->sysctl_wmem_offset) 2566 return *(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset); 2567 2568 return *proto->sysctl_wmem; 2569 } 2570 2571 static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto) 2572 { 2573 /* Does this proto have per netns sysctl_rmem ? */ 2574 if (proto->sysctl_rmem_offset) 2575 return *(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset); 2576 2577 return *proto->sysctl_rmem; 2578 } 2579 2580 /* Default TCP Small queue budget is ~1 ms of data (1sec >> 10) 2581 * Some wifi drivers need to tweak it to get more chunks. 2582 * They can use this helper from their ndo_start_xmit() 2583 */ 2584 static inline void sk_pacing_shift_update(struct sock *sk, int val) 2585 { 2586 if (!sk || !sk_fullsock(sk) || sk->sk_pacing_shift == val) 2587 return; 2588 sk->sk_pacing_shift = val; 2589 } 2590 2591 /* if a socket is bound to a device, check that the given device 2592 * index is either the same or that the socket is bound to an L3 2593 * master device and the given device index is also enslaved to 2594 * that L3 master 2595 */ 2596 static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif) 2597 { 2598 int mdif; 2599 2600 if (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dif) 2601 return true; 2602 2603 mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif); 2604 if (mdif && mdif == sk->sk_bound_dev_if) 2605 return true; 2606 2607 return false; 2608 } 2609 2610 #endif /* _SOCK_H */ 2611