1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* 3 * INET An implementation of the TCP/IP protocol suite for the LINUX 4 * operating system. INET is implemented using the BSD Socket 5 * interface as the means of communication with the user level. 6 * 7 * Definitions for the AF_INET socket handler. 8 * 9 * Version: @(#)sock.h 1.0.4 05/13/93 10 * 11 * Authors: Ross Biro 12 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 13 * Corey Minyard <wf-rch!minyard@relay.EU.net> 14 * Florian La Roche <flla@stud.uni-sb.de> 15 * 16 * Fixes: 17 * Alan Cox : Volatiles in skbuff pointers. See 18 * skbuff comments. May be overdone, 19 * better to prove they can be removed 20 * than the reverse. 21 * Alan Cox : Added a zapped field for tcp to note 22 * a socket is reset and must stay shut up 23 * Alan Cox : New fields for options 24 * Pauline Middelink : identd support 25 * Alan Cox : Eliminate low level recv/recvfrom 26 * David S. Miller : New socket lookup architecture. 27 * Steve Whitehouse: Default routines for sock_ops 28 * Arnaldo C. Melo : removed net_pinfo, tp_pinfo and made 29 * protinfo be just a void pointer, as the 30 * protocol specific parts were moved to 31 * respective headers and ipv4/v6, etc now 32 * use private slabcaches for its socks 33 * Pedro Hortas : New flags field for socket options 34 */ 35 #ifndef _SOCK_H 36 #define _SOCK_H 37 38 #include <linux/hardirq.h> 39 #include <linux/kernel.h> 40 #include <linux/list.h> 41 #include <linux/list_nulls.h> 42 #include <linux/timer.h> 43 #include <linux/cache.h> 44 #include <linux/bitops.h> 45 #include <linux/lockdep.h> 46 #include <linux/netdevice.h> 47 #include <linux/skbuff.h> /* struct sk_buff */ 48 #include <linux/mm.h> 49 #include <linux/security.h> 50 #include <linux/slab.h> 51 #include <linux/uaccess.h> 52 #include <linux/page_counter.h> 53 #include <linux/memcontrol.h> 54 #include <linux/static_key.h> 55 #include <linux/sched.h> 56 #include <linux/wait.h> 57 #include <linux/cgroup-defs.h> 58 #include <linux/rbtree.h> 59 #include <linux/filter.h> 60 #include <linux/rculist_nulls.h> 61 #include <linux/poll.h> 62 #include <linux/sockptr.h> 63 #include <linux/indirect_call_wrapper.h> 64 #include <linux/atomic.h> 65 #include <linux/refcount.h> 66 #include <net/dst.h> 67 #include <net/checksum.h> 68 #include <net/tcp_states.h> 69 #include <linux/net_tstamp.h> 70 #include <net/l3mdev.h> 71 72 /* 73 * This structure really needs to be cleaned up. 74 * Most of it is for TCP, and not used by any of 75 * the other protocols. 76 */ 77 78 /* Define this to get the SOCK_DBG debugging facility. */ 79 #define SOCK_DEBUGGING 80 #ifdef SOCK_DEBUGGING 81 #define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \ 82 printk(KERN_DEBUG msg); } while (0) 83 #else 84 /* Validate arguments and do nothing */ 85 static inline __printf(2, 3) 86 void SOCK_DEBUG(const struct sock *sk, const char *msg, ...) 87 { 88 } 89 #endif 90 91 /* This is the per-socket lock. The spinlock provides a synchronization 92 * between user contexts and software interrupt processing, whereas the 93 * mini-semaphore synchronizes multiple users amongst themselves. 94 */ 95 typedef struct { 96 spinlock_t slock; 97 int owned; 98 wait_queue_head_t wq; 99 /* 100 * We express the mutex-alike socket_lock semantics 101 * to the lock validator by explicitly managing 102 * the slock as a lock variant (in addition to 103 * the slock itself): 104 */ 105 #ifdef CONFIG_DEBUG_LOCK_ALLOC 106 struct lockdep_map dep_map; 107 #endif 108 } socket_lock_t; 109 110 struct sock; 111 struct proto; 112 struct net; 113 114 typedef __u32 __bitwise __portpair; 115 typedef __u64 __bitwise __addrpair; 116 117 /** 118 * struct sock_common - minimal network layer representation of sockets 119 * @skc_daddr: Foreign IPv4 addr 120 * @skc_rcv_saddr: Bound local IPv4 addr 121 * @skc_addrpair: 8-byte-aligned __u64 union of @skc_daddr & @skc_rcv_saddr 122 * @skc_hash: hash value used with various protocol lookup tables 123 * @skc_u16hashes: two u16 hash values used by UDP lookup tables 124 * @skc_dport: placeholder for inet_dport/tw_dport 125 * @skc_num: placeholder for inet_num/tw_num 126 * @skc_portpair: __u32 union of @skc_dport & @skc_num 127 * @skc_family: network address family 128 * @skc_state: Connection state 129 * @skc_reuse: %SO_REUSEADDR setting 130 * @skc_reuseport: %SO_REUSEPORT setting 131 * @skc_ipv6only: socket is IPV6 only 132 * @skc_net_refcnt: socket is using net ref counting 133 * @skc_bound_dev_if: bound device index if != 0 134 * @skc_bind_node: bind hash linkage for various protocol lookup tables 135 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol 136 * @skc_prot: protocol handlers inside a network family 137 * @skc_net: reference to the network namespace of this socket 138 * @skc_v6_daddr: IPV6 destination address 139 * @skc_v6_rcv_saddr: IPV6 source address 140 * @skc_cookie: socket's cookie value 141 * @skc_node: main hash linkage for various protocol lookup tables 142 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol 143 * @skc_tx_queue_mapping: tx queue number for this connection 144 * @skc_rx_queue_mapping: rx queue number for this connection 145 * @skc_flags: place holder for sk_flags 146 * %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE, 147 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings 148 * @skc_listener: connection request listener socket (aka rsk_listener) 149 * [union with @skc_flags] 150 * @skc_tw_dr: (aka tw_dr) ptr to &struct inet_timewait_death_row 151 * [union with @skc_flags] 152 * @skc_incoming_cpu: record/match cpu processing incoming packets 153 * @skc_rcv_wnd: (aka rsk_rcv_wnd) TCP receive window size (possibly scaled) 154 * [union with @skc_incoming_cpu] 155 * @skc_tw_rcv_nxt: (aka tw_rcv_nxt) TCP window next expected seq number 156 * [union with @skc_incoming_cpu] 157 * @skc_refcnt: reference count 158 * 159 * This is the minimal network layer representation of sockets, the header 160 * for struct sock and struct inet_timewait_sock. 161 */ 162 struct sock_common { 163 /* skc_daddr and skc_rcv_saddr must be grouped on a 8 bytes aligned 164 * address on 64bit arches : cf INET_MATCH() 165 */ 166 union { 167 __addrpair skc_addrpair; 168 struct { 169 __be32 skc_daddr; 170 __be32 skc_rcv_saddr; 171 }; 172 }; 173 union { 174 unsigned int skc_hash; 175 __u16 skc_u16hashes[2]; 176 }; 177 /* skc_dport && skc_num must be grouped as well */ 178 union { 179 __portpair skc_portpair; 180 struct { 181 __be16 skc_dport; 182 __u16 skc_num; 183 }; 184 }; 185 186 unsigned short skc_family; 187 volatile unsigned char skc_state; 188 unsigned char skc_reuse:4; 189 unsigned char skc_reuseport:1; 190 unsigned char skc_ipv6only:1; 191 unsigned char skc_net_refcnt:1; 192 int skc_bound_dev_if; 193 union { 194 struct hlist_node skc_bind_node; 195 struct hlist_node skc_portaddr_node; 196 }; 197 struct proto *skc_prot; 198 possible_net_t skc_net; 199 200 #if IS_ENABLED(CONFIG_IPV6) 201 struct in6_addr skc_v6_daddr; 202 struct in6_addr skc_v6_rcv_saddr; 203 #endif 204 205 atomic64_t skc_cookie; 206 207 /* following fields are padding to force 208 * offset(struct sock, sk_refcnt) == 128 on 64bit arches 209 * assuming IPV6 is enabled. We use this padding differently 210 * for different kind of 'sockets' 211 */ 212 union { 213 unsigned long skc_flags; 214 struct sock *skc_listener; /* request_sock */ 215 struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */ 216 }; 217 /* 218 * fields between dontcopy_begin/dontcopy_end 219 * are not copied in sock_copy() 220 */ 221 /* private: */ 222 int skc_dontcopy_begin[0]; 223 /* public: */ 224 union { 225 struct hlist_node skc_node; 226 struct hlist_nulls_node skc_nulls_node; 227 }; 228 unsigned short skc_tx_queue_mapping; 229 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 230 unsigned short skc_rx_queue_mapping; 231 #endif 232 union { 233 int skc_incoming_cpu; 234 u32 skc_rcv_wnd; 235 u32 skc_tw_rcv_nxt; /* struct tcp_timewait_sock */ 236 }; 237 238 refcount_t skc_refcnt; 239 /* private: */ 240 int skc_dontcopy_end[0]; 241 union { 242 u32 skc_rxhash; 243 u32 skc_window_clamp; 244 u32 skc_tw_snd_nxt; /* struct tcp_timewait_sock */ 245 }; 246 /* public: */ 247 }; 248 249 struct bpf_local_storage; 250 251 /** 252 * struct sock - network layer representation of sockets 253 * @__sk_common: shared layout with inet_timewait_sock 254 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN 255 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings 256 * @sk_lock: synchronizer 257 * @sk_kern_sock: True if sock is using kernel lock classes 258 * @sk_rcvbuf: size of receive buffer in bytes 259 * @sk_wq: sock wait queue and async head 260 * @sk_rx_dst: receive input route used by early demux 261 * @sk_dst_cache: destination cache 262 * @sk_dst_pending_confirm: need to confirm neighbour 263 * @sk_policy: flow policy 264 * @sk_rx_skb_cache: cache copy of recently accessed RX skb 265 * @sk_receive_queue: incoming packets 266 * @sk_wmem_alloc: transmit queue bytes committed 267 * @sk_tsq_flags: TCP Small Queues flags 268 * @sk_write_queue: Packet sending queue 269 * @sk_omem_alloc: "o" is "option" or "other" 270 * @sk_wmem_queued: persistent queue size 271 * @sk_forward_alloc: space allocated forward 272 * @sk_napi_id: id of the last napi context to receive data for sk 273 * @sk_ll_usec: usecs to busypoll when there is no data 274 * @sk_allocation: allocation mode 275 * @sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler) 276 * @sk_pacing_status: Pacing status (requested, handled by sch_fq) 277 * @sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE) 278 * @sk_sndbuf: size of send buffer in bytes 279 * @__sk_flags_offset: empty field used to determine location of bitfield 280 * @sk_padding: unused element for alignment 281 * @sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets 282 * @sk_no_check_rx: allow zero checksum in RX packets 283 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO) 284 * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK) 285 * @sk_route_forced_caps: static, forced route capabilities 286 * (set in tcp_init_sock()) 287 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4) 288 * @sk_gso_max_size: Maximum GSO segment size to build 289 * @sk_gso_max_segs: Maximum number of GSO segments 290 * @sk_pacing_shift: scaling factor for TCP Small Queues 291 * @sk_lingertime: %SO_LINGER l_linger setting 292 * @sk_backlog: always used with the per-socket spinlock held 293 * @sk_callback_lock: used with the callbacks in the end of this struct 294 * @sk_error_queue: rarely used 295 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt, 296 * IPV6_ADDRFORM for instance) 297 * @sk_err: last error 298 * @sk_err_soft: errors that don't cause failure but are the cause of a 299 * persistent failure not just 'timed out' 300 * @sk_drops: raw/udp drops counter 301 * @sk_ack_backlog: current listen backlog 302 * @sk_max_ack_backlog: listen backlog set in listen() 303 * @sk_uid: user id of owner 304 * @sk_prefer_busy_poll: prefer busypolling over softirq processing 305 * @sk_busy_poll_budget: napi processing budget when busypolling 306 * @sk_priority: %SO_PRIORITY setting 307 * @sk_type: socket type (%SOCK_STREAM, etc) 308 * @sk_protocol: which protocol this socket belongs in this network family 309 * @sk_peer_pid: &struct pid for this socket's peer 310 * @sk_peer_cred: %SO_PEERCRED setting 311 * @sk_rcvlowat: %SO_RCVLOWAT setting 312 * @sk_rcvtimeo: %SO_RCVTIMEO setting 313 * @sk_sndtimeo: %SO_SNDTIMEO setting 314 * @sk_txhash: computed flow hash for use on transmit 315 * @sk_filter: socket filtering instructions 316 * @sk_timer: sock cleanup timer 317 * @sk_stamp: time stamp of last packet received 318 * @sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only 319 * @sk_tsflags: SO_TIMESTAMPING socket options 320 * @sk_tskey: counter to disambiguate concurrent tstamp requests 321 * @sk_zckey: counter to order MSG_ZEROCOPY notifications 322 * @sk_socket: Identd and reporting IO signals 323 * @sk_user_data: RPC layer private data 324 * @sk_frag: cached page frag 325 * @sk_peek_off: current peek_offset value 326 * @sk_send_head: front of stuff to transmit 327 * @tcp_rtx_queue: TCP re-transmit queue [union with @sk_send_head] 328 * @sk_tx_skb_cache: cache copy of recently accessed TX skb 329 * @sk_security: used by security modules 330 * @sk_mark: generic packet mark 331 * @sk_cgrp_data: cgroup data for this cgroup 332 * @sk_memcg: this socket's memory cgroup association 333 * @sk_write_pending: a write to stream socket waits to start 334 * @sk_state_change: callback to indicate change in the state of the sock 335 * @sk_data_ready: callback to indicate there is data to be processed 336 * @sk_write_space: callback to indicate there is bf sending space available 337 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE) 338 * @sk_backlog_rcv: callback to process the backlog 339 * @sk_validate_xmit_skb: ptr to an optional validate function 340 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0 341 * @sk_reuseport_cb: reuseport group container 342 * @sk_bpf_storage: ptr to cache and control for bpf_sk_storage 343 * @sk_rcu: used during RCU grace period 344 * @sk_clockid: clockid used by time-based scheduling (SO_TXTIME) 345 * @sk_txtime_deadline_mode: set deadline mode for SO_TXTIME 346 * @sk_txtime_report_errors: set report errors mode for SO_TXTIME 347 * @sk_txtime_unused: unused txtime flags 348 */ 349 struct sock { 350 /* 351 * Now struct inet_timewait_sock also uses sock_common, so please just 352 * don't add nothing before this first member (__sk_common) --acme 353 */ 354 struct sock_common __sk_common; 355 #define sk_node __sk_common.skc_node 356 #define sk_nulls_node __sk_common.skc_nulls_node 357 #define sk_refcnt __sk_common.skc_refcnt 358 #define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping 359 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 360 #define sk_rx_queue_mapping __sk_common.skc_rx_queue_mapping 361 #endif 362 363 #define sk_dontcopy_begin __sk_common.skc_dontcopy_begin 364 #define sk_dontcopy_end __sk_common.skc_dontcopy_end 365 #define sk_hash __sk_common.skc_hash 366 #define sk_portpair __sk_common.skc_portpair 367 #define sk_num __sk_common.skc_num 368 #define sk_dport __sk_common.skc_dport 369 #define sk_addrpair __sk_common.skc_addrpair 370 #define sk_daddr __sk_common.skc_daddr 371 #define sk_rcv_saddr __sk_common.skc_rcv_saddr 372 #define sk_family __sk_common.skc_family 373 #define sk_state __sk_common.skc_state 374 #define sk_reuse __sk_common.skc_reuse 375 #define sk_reuseport __sk_common.skc_reuseport 376 #define sk_ipv6only __sk_common.skc_ipv6only 377 #define sk_net_refcnt __sk_common.skc_net_refcnt 378 #define sk_bound_dev_if __sk_common.skc_bound_dev_if 379 #define sk_bind_node __sk_common.skc_bind_node 380 #define sk_prot __sk_common.skc_prot 381 #define sk_net __sk_common.skc_net 382 #define sk_v6_daddr __sk_common.skc_v6_daddr 383 #define sk_v6_rcv_saddr __sk_common.skc_v6_rcv_saddr 384 #define sk_cookie __sk_common.skc_cookie 385 #define sk_incoming_cpu __sk_common.skc_incoming_cpu 386 #define sk_flags __sk_common.skc_flags 387 #define sk_rxhash __sk_common.skc_rxhash 388 389 socket_lock_t sk_lock; 390 atomic_t sk_drops; 391 int sk_rcvlowat; 392 struct sk_buff_head sk_error_queue; 393 struct sk_buff *sk_rx_skb_cache; 394 struct sk_buff_head sk_receive_queue; 395 /* 396 * The backlog queue is special, it is always used with 397 * the per-socket spinlock held and requires low latency 398 * access. Therefore we special case it's implementation. 399 * Note : rmem_alloc is in this structure to fill a hole 400 * on 64bit arches, not because its logically part of 401 * backlog. 402 */ 403 struct { 404 atomic_t rmem_alloc; 405 int len; 406 struct sk_buff *head; 407 struct sk_buff *tail; 408 } sk_backlog; 409 #define sk_rmem_alloc sk_backlog.rmem_alloc 410 411 int sk_forward_alloc; 412 #ifdef CONFIG_NET_RX_BUSY_POLL 413 unsigned int sk_ll_usec; 414 /* ===== mostly read cache line ===== */ 415 unsigned int sk_napi_id; 416 #endif 417 int sk_rcvbuf; 418 419 struct sk_filter __rcu *sk_filter; 420 union { 421 struct socket_wq __rcu *sk_wq; 422 /* private: */ 423 struct socket_wq *sk_wq_raw; 424 /* public: */ 425 }; 426 #ifdef CONFIG_XFRM 427 struct xfrm_policy __rcu *sk_policy[2]; 428 #endif 429 struct dst_entry *sk_rx_dst; 430 struct dst_entry __rcu *sk_dst_cache; 431 atomic_t sk_omem_alloc; 432 int sk_sndbuf; 433 434 /* ===== cache line for TX ===== */ 435 int sk_wmem_queued; 436 refcount_t sk_wmem_alloc; 437 unsigned long sk_tsq_flags; 438 union { 439 struct sk_buff *sk_send_head; 440 struct rb_root tcp_rtx_queue; 441 }; 442 struct sk_buff *sk_tx_skb_cache; 443 struct sk_buff_head sk_write_queue; 444 __s32 sk_peek_off; 445 int sk_write_pending; 446 __u32 sk_dst_pending_confirm; 447 u32 sk_pacing_status; /* see enum sk_pacing */ 448 long sk_sndtimeo; 449 struct timer_list sk_timer; 450 __u32 sk_priority; 451 __u32 sk_mark; 452 unsigned long sk_pacing_rate; /* bytes per second */ 453 unsigned long sk_max_pacing_rate; 454 struct page_frag sk_frag; 455 netdev_features_t sk_route_caps; 456 netdev_features_t sk_route_nocaps; 457 netdev_features_t sk_route_forced_caps; 458 int sk_gso_type; 459 unsigned int sk_gso_max_size; 460 gfp_t sk_allocation; 461 __u32 sk_txhash; 462 463 /* 464 * Because of non atomicity rules, all 465 * changes are protected by socket lock. 466 */ 467 u8 sk_padding : 1, 468 sk_kern_sock : 1, 469 sk_no_check_tx : 1, 470 sk_no_check_rx : 1, 471 sk_userlocks : 4; 472 u8 sk_pacing_shift; 473 u16 sk_type; 474 u16 sk_protocol; 475 u16 sk_gso_max_segs; 476 unsigned long sk_lingertime; 477 struct proto *sk_prot_creator; 478 rwlock_t sk_callback_lock; 479 int sk_err, 480 sk_err_soft; 481 u32 sk_ack_backlog; 482 u32 sk_max_ack_backlog; 483 kuid_t sk_uid; 484 #ifdef CONFIG_NET_RX_BUSY_POLL 485 u8 sk_prefer_busy_poll; 486 u16 sk_busy_poll_budget; 487 #endif 488 struct pid *sk_peer_pid; 489 const struct cred *sk_peer_cred; 490 long sk_rcvtimeo; 491 ktime_t sk_stamp; 492 #if BITS_PER_LONG==32 493 seqlock_t sk_stamp_seq; 494 #endif 495 u16 sk_tsflags; 496 u8 sk_shutdown; 497 u32 sk_tskey; 498 atomic_t sk_zckey; 499 500 u8 sk_clockid; 501 u8 sk_txtime_deadline_mode : 1, 502 sk_txtime_report_errors : 1, 503 sk_txtime_unused : 6; 504 505 struct socket *sk_socket; 506 void *sk_user_data; 507 #ifdef CONFIG_SECURITY 508 void *sk_security; 509 #endif 510 struct sock_cgroup_data sk_cgrp_data; 511 struct mem_cgroup *sk_memcg; 512 void (*sk_state_change)(struct sock *sk); 513 void (*sk_data_ready)(struct sock *sk); 514 void (*sk_write_space)(struct sock *sk); 515 void (*sk_error_report)(struct sock *sk); 516 int (*sk_backlog_rcv)(struct sock *sk, 517 struct sk_buff *skb); 518 #ifdef CONFIG_SOCK_VALIDATE_XMIT 519 struct sk_buff* (*sk_validate_xmit_skb)(struct sock *sk, 520 struct net_device *dev, 521 struct sk_buff *skb); 522 #endif 523 void (*sk_destruct)(struct sock *sk); 524 struct sock_reuseport __rcu *sk_reuseport_cb; 525 #ifdef CONFIG_BPF_SYSCALL 526 struct bpf_local_storage __rcu *sk_bpf_storage; 527 #endif 528 struct rcu_head sk_rcu; 529 }; 530 531 enum sk_pacing { 532 SK_PACING_NONE = 0, 533 SK_PACING_NEEDED = 1, 534 SK_PACING_FQ = 2, 535 }; 536 537 /* Pointer stored in sk_user_data might not be suitable for copying 538 * when cloning the socket. For instance, it can point to a reference 539 * counted object. sk_user_data bottom bit is set if pointer must not 540 * be copied. 541 */ 542 #define SK_USER_DATA_NOCOPY 1UL 543 #define SK_USER_DATA_BPF 2UL /* Managed by BPF */ 544 #define SK_USER_DATA_PTRMASK ~(SK_USER_DATA_NOCOPY | SK_USER_DATA_BPF) 545 546 /** 547 * sk_user_data_is_nocopy - Test if sk_user_data pointer must not be copied 548 * @sk: socket 549 */ 550 static inline bool sk_user_data_is_nocopy(const struct sock *sk) 551 { 552 return ((uintptr_t)sk->sk_user_data & SK_USER_DATA_NOCOPY); 553 } 554 555 #define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data))) 556 557 #define rcu_dereference_sk_user_data(sk) \ 558 ({ \ 559 void *__tmp = rcu_dereference(__sk_user_data((sk))); \ 560 (void *)((uintptr_t)__tmp & SK_USER_DATA_PTRMASK); \ 561 }) 562 #define rcu_assign_sk_user_data(sk, ptr) \ 563 ({ \ 564 uintptr_t __tmp = (uintptr_t)(ptr); \ 565 WARN_ON_ONCE(__tmp & ~SK_USER_DATA_PTRMASK); \ 566 rcu_assign_pointer(__sk_user_data((sk)), __tmp); \ 567 }) 568 #define rcu_assign_sk_user_data_nocopy(sk, ptr) \ 569 ({ \ 570 uintptr_t __tmp = (uintptr_t)(ptr); \ 571 WARN_ON_ONCE(__tmp & ~SK_USER_DATA_PTRMASK); \ 572 rcu_assign_pointer(__sk_user_data((sk)), \ 573 __tmp | SK_USER_DATA_NOCOPY); \ 574 }) 575 576 /* 577 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK 578 * or not whether his port will be reused by someone else. SK_FORCE_REUSE 579 * on a socket means that the socket will reuse everybody else's port 580 * without looking at the other's sk_reuse value. 581 */ 582 583 #define SK_NO_REUSE 0 584 #define SK_CAN_REUSE 1 585 #define SK_FORCE_REUSE 2 586 587 int sk_set_peek_off(struct sock *sk, int val); 588 589 static inline int sk_peek_offset(struct sock *sk, int flags) 590 { 591 if (unlikely(flags & MSG_PEEK)) { 592 return READ_ONCE(sk->sk_peek_off); 593 } 594 595 return 0; 596 } 597 598 static inline void sk_peek_offset_bwd(struct sock *sk, int val) 599 { 600 s32 off = READ_ONCE(sk->sk_peek_off); 601 602 if (unlikely(off >= 0)) { 603 off = max_t(s32, off - val, 0); 604 WRITE_ONCE(sk->sk_peek_off, off); 605 } 606 } 607 608 static inline void sk_peek_offset_fwd(struct sock *sk, int val) 609 { 610 sk_peek_offset_bwd(sk, -val); 611 } 612 613 /* 614 * Hashed lists helper routines 615 */ 616 static inline struct sock *sk_entry(const struct hlist_node *node) 617 { 618 return hlist_entry(node, struct sock, sk_node); 619 } 620 621 static inline struct sock *__sk_head(const struct hlist_head *head) 622 { 623 return hlist_entry(head->first, struct sock, sk_node); 624 } 625 626 static inline struct sock *sk_head(const struct hlist_head *head) 627 { 628 return hlist_empty(head) ? NULL : __sk_head(head); 629 } 630 631 static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head) 632 { 633 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node); 634 } 635 636 static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head) 637 { 638 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head); 639 } 640 641 static inline struct sock *sk_next(const struct sock *sk) 642 { 643 return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node); 644 } 645 646 static inline struct sock *sk_nulls_next(const struct sock *sk) 647 { 648 return (!is_a_nulls(sk->sk_nulls_node.next)) ? 649 hlist_nulls_entry(sk->sk_nulls_node.next, 650 struct sock, sk_nulls_node) : 651 NULL; 652 } 653 654 static inline bool sk_unhashed(const struct sock *sk) 655 { 656 return hlist_unhashed(&sk->sk_node); 657 } 658 659 static inline bool sk_hashed(const struct sock *sk) 660 { 661 return !sk_unhashed(sk); 662 } 663 664 static inline void sk_node_init(struct hlist_node *node) 665 { 666 node->pprev = NULL; 667 } 668 669 static inline void sk_nulls_node_init(struct hlist_nulls_node *node) 670 { 671 node->pprev = NULL; 672 } 673 674 static inline void __sk_del_node(struct sock *sk) 675 { 676 __hlist_del(&sk->sk_node); 677 } 678 679 /* NB: equivalent to hlist_del_init_rcu */ 680 static inline bool __sk_del_node_init(struct sock *sk) 681 { 682 if (sk_hashed(sk)) { 683 __sk_del_node(sk); 684 sk_node_init(&sk->sk_node); 685 return true; 686 } 687 return false; 688 } 689 690 /* Grab socket reference count. This operation is valid only 691 when sk is ALREADY grabbed f.e. it is found in hash table 692 or a list and the lookup is made under lock preventing hash table 693 modifications. 694 */ 695 696 static __always_inline void sock_hold(struct sock *sk) 697 { 698 refcount_inc(&sk->sk_refcnt); 699 } 700 701 /* Ungrab socket in the context, which assumes that socket refcnt 702 cannot hit zero, f.e. it is true in context of any socketcall. 703 */ 704 static __always_inline void __sock_put(struct sock *sk) 705 { 706 refcount_dec(&sk->sk_refcnt); 707 } 708 709 static inline bool sk_del_node_init(struct sock *sk) 710 { 711 bool rc = __sk_del_node_init(sk); 712 713 if (rc) { 714 /* paranoid for a while -acme */ 715 WARN_ON(refcount_read(&sk->sk_refcnt) == 1); 716 __sock_put(sk); 717 } 718 return rc; 719 } 720 #define sk_del_node_init_rcu(sk) sk_del_node_init(sk) 721 722 static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk) 723 { 724 if (sk_hashed(sk)) { 725 hlist_nulls_del_init_rcu(&sk->sk_nulls_node); 726 return true; 727 } 728 return false; 729 } 730 731 static inline bool sk_nulls_del_node_init_rcu(struct sock *sk) 732 { 733 bool rc = __sk_nulls_del_node_init_rcu(sk); 734 735 if (rc) { 736 /* paranoid for a while -acme */ 737 WARN_ON(refcount_read(&sk->sk_refcnt) == 1); 738 __sock_put(sk); 739 } 740 return rc; 741 } 742 743 static inline void __sk_add_node(struct sock *sk, struct hlist_head *list) 744 { 745 hlist_add_head(&sk->sk_node, list); 746 } 747 748 static inline void sk_add_node(struct sock *sk, struct hlist_head *list) 749 { 750 sock_hold(sk); 751 __sk_add_node(sk, list); 752 } 753 754 static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list) 755 { 756 sock_hold(sk); 757 if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport && 758 sk->sk_family == AF_INET6) 759 hlist_add_tail_rcu(&sk->sk_node, list); 760 else 761 hlist_add_head_rcu(&sk->sk_node, list); 762 } 763 764 static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list) 765 { 766 sock_hold(sk); 767 hlist_add_tail_rcu(&sk->sk_node, list); 768 } 769 770 static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list) 771 { 772 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list); 773 } 774 775 static inline void __sk_nulls_add_node_tail_rcu(struct sock *sk, struct hlist_nulls_head *list) 776 { 777 hlist_nulls_add_tail_rcu(&sk->sk_nulls_node, list); 778 } 779 780 static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list) 781 { 782 sock_hold(sk); 783 __sk_nulls_add_node_rcu(sk, list); 784 } 785 786 static inline void __sk_del_bind_node(struct sock *sk) 787 { 788 __hlist_del(&sk->sk_bind_node); 789 } 790 791 static inline void sk_add_bind_node(struct sock *sk, 792 struct hlist_head *list) 793 { 794 hlist_add_head(&sk->sk_bind_node, list); 795 } 796 797 #define sk_for_each(__sk, list) \ 798 hlist_for_each_entry(__sk, list, sk_node) 799 #define sk_for_each_rcu(__sk, list) \ 800 hlist_for_each_entry_rcu(__sk, list, sk_node) 801 #define sk_nulls_for_each(__sk, node, list) \ 802 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node) 803 #define sk_nulls_for_each_rcu(__sk, node, list) \ 804 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node) 805 #define sk_for_each_from(__sk) \ 806 hlist_for_each_entry_from(__sk, sk_node) 807 #define sk_nulls_for_each_from(__sk, node) \ 808 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \ 809 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node) 810 #define sk_for_each_safe(__sk, tmp, list) \ 811 hlist_for_each_entry_safe(__sk, tmp, list, sk_node) 812 #define sk_for_each_bound(__sk, list) \ 813 hlist_for_each_entry(__sk, list, sk_bind_node) 814 815 /** 816 * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset 817 * @tpos: the type * to use as a loop cursor. 818 * @pos: the &struct hlist_node to use as a loop cursor. 819 * @head: the head for your list. 820 * @offset: offset of hlist_node within the struct. 821 * 822 */ 823 #define sk_for_each_entry_offset_rcu(tpos, pos, head, offset) \ 824 for (pos = rcu_dereference(hlist_first_rcu(head)); \ 825 pos != NULL && \ 826 ({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \ 827 pos = rcu_dereference(hlist_next_rcu(pos))) 828 829 static inline struct user_namespace *sk_user_ns(struct sock *sk) 830 { 831 /* Careful only use this in a context where these parameters 832 * can not change and must all be valid, such as recvmsg from 833 * userspace. 834 */ 835 return sk->sk_socket->file->f_cred->user_ns; 836 } 837 838 /* Sock flags */ 839 enum sock_flags { 840 SOCK_DEAD, 841 SOCK_DONE, 842 SOCK_URGINLINE, 843 SOCK_KEEPOPEN, 844 SOCK_LINGER, 845 SOCK_DESTROY, 846 SOCK_BROADCAST, 847 SOCK_TIMESTAMP, 848 SOCK_ZAPPED, 849 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */ 850 SOCK_DBG, /* %SO_DEBUG setting */ 851 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */ 852 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */ 853 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */ 854 SOCK_MEMALLOC, /* VM depends on this socket for swapping */ 855 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */ 856 SOCK_FASYNC, /* fasync() active */ 857 SOCK_RXQ_OVFL, 858 SOCK_ZEROCOPY, /* buffers from userspace */ 859 SOCK_WIFI_STATUS, /* push wifi status to userspace */ 860 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS. 861 * Will use last 4 bytes of packet sent from 862 * user-space instead. 863 */ 864 SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */ 865 SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */ 866 SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */ 867 SOCK_TXTIME, 868 SOCK_XDP, /* XDP is attached */ 869 SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */ 870 }; 871 872 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)) 873 874 static inline void sock_copy_flags(struct sock *nsk, struct sock *osk) 875 { 876 nsk->sk_flags = osk->sk_flags; 877 } 878 879 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag) 880 { 881 __set_bit(flag, &sk->sk_flags); 882 } 883 884 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag) 885 { 886 __clear_bit(flag, &sk->sk_flags); 887 } 888 889 static inline void sock_valbool_flag(struct sock *sk, enum sock_flags bit, 890 int valbool) 891 { 892 if (valbool) 893 sock_set_flag(sk, bit); 894 else 895 sock_reset_flag(sk, bit); 896 } 897 898 static inline bool sock_flag(const struct sock *sk, enum sock_flags flag) 899 { 900 return test_bit(flag, &sk->sk_flags); 901 } 902 903 #ifdef CONFIG_NET 904 DECLARE_STATIC_KEY_FALSE(memalloc_socks_key); 905 static inline int sk_memalloc_socks(void) 906 { 907 return static_branch_unlikely(&memalloc_socks_key); 908 } 909 910 void __receive_sock(struct file *file); 911 #else 912 913 static inline int sk_memalloc_socks(void) 914 { 915 return 0; 916 } 917 918 static inline void __receive_sock(struct file *file) 919 { } 920 #endif 921 922 static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask) 923 { 924 return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC); 925 } 926 927 static inline void sk_acceptq_removed(struct sock *sk) 928 { 929 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1); 930 } 931 932 static inline void sk_acceptq_added(struct sock *sk) 933 { 934 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1); 935 } 936 937 /* Note: If you think the test should be: 938 * return READ_ONCE(sk->sk_ack_backlog) >= READ_ONCE(sk->sk_max_ack_backlog); 939 * Then please take a look at commit 64a146513f8f ("[NET]: Revert incorrect accept queue backlog changes.") 940 */ 941 static inline bool sk_acceptq_is_full(const struct sock *sk) 942 { 943 return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(sk->sk_max_ack_backlog); 944 } 945 946 /* 947 * Compute minimal free write space needed to queue new packets. 948 */ 949 static inline int sk_stream_min_wspace(const struct sock *sk) 950 { 951 return READ_ONCE(sk->sk_wmem_queued) >> 1; 952 } 953 954 static inline int sk_stream_wspace(const struct sock *sk) 955 { 956 return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued); 957 } 958 959 static inline void sk_wmem_queued_add(struct sock *sk, int val) 960 { 961 WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val); 962 } 963 964 void sk_stream_write_space(struct sock *sk); 965 966 /* OOB backlog add */ 967 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb) 968 { 969 /* dont let skb dst not refcounted, we are going to leave rcu lock */ 970 skb_dst_force(skb); 971 972 if (!sk->sk_backlog.tail) 973 WRITE_ONCE(sk->sk_backlog.head, skb); 974 else 975 sk->sk_backlog.tail->next = skb; 976 977 WRITE_ONCE(sk->sk_backlog.tail, skb); 978 skb->next = NULL; 979 } 980 981 /* 982 * Take into account size of receive queue and backlog queue 983 * Do not take into account this skb truesize, 984 * to allow even a single big packet to come. 985 */ 986 static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit) 987 { 988 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc); 989 990 return qsize > limit; 991 } 992 993 /* The per-socket spinlock must be held here. */ 994 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb, 995 unsigned int limit) 996 { 997 if (sk_rcvqueues_full(sk, limit)) 998 return -ENOBUFS; 999 1000 /* 1001 * If the skb was allocated from pfmemalloc reserves, only 1002 * allow SOCK_MEMALLOC sockets to use it as this socket is 1003 * helping free memory 1004 */ 1005 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) 1006 return -ENOMEM; 1007 1008 __sk_add_backlog(sk, skb); 1009 sk->sk_backlog.len += skb->truesize; 1010 return 0; 1011 } 1012 1013 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb); 1014 1015 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 1016 { 1017 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) 1018 return __sk_backlog_rcv(sk, skb); 1019 1020 return sk->sk_backlog_rcv(sk, skb); 1021 } 1022 1023 static inline void sk_incoming_cpu_update(struct sock *sk) 1024 { 1025 int cpu = raw_smp_processor_id(); 1026 1027 if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu)) 1028 WRITE_ONCE(sk->sk_incoming_cpu, cpu); 1029 } 1030 1031 static inline void sock_rps_record_flow_hash(__u32 hash) 1032 { 1033 #ifdef CONFIG_RPS 1034 struct rps_sock_flow_table *sock_flow_table; 1035 1036 rcu_read_lock(); 1037 sock_flow_table = rcu_dereference(rps_sock_flow_table); 1038 rps_record_sock_flow(sock_flow_table, hash); 1039 rcu_read_unlock(); 1040 #endif 1041 } 1042 1043 static inline void sock_rps_record_flow(const struct sock *sk) 1044 { 1045 #ifdef CONFIG_RPS 1046 if (static_branch_unlikely(&rfs_needed)) { 1047 /* Reading sk->sk_rxhash might incur an expensive cache line 1048 * miss. 1049 * 1050 * TCP_ESTABLISHED does cover almost all states where RFS 1051 * might be useful, and is cheaper [1] than testing : 1052 * IPv4: inet_sk(sk)->inet_daddr 1053 * IPv6: ipv6_addr_any(&sk->sk_v6_daddr) 1054 * OR an additional socket flag 1055 * [1] : sk_state and sk_prot are in the same cache line. 1056 */ 1057 if (sk->sk_state == TCP_ESTABLISHED) 1058 sock_rps_record_flow_hash(sk->sk_rxhash); 1059 } 1060 #endif 1061 } 1062 1063 static inline void sock_rps_save_rxhash(struct sock *sk, 1064 const struct sk_buff *skb) 1065 { 1066 #ifdef CONFIG_RPS 1067 if (unlikely(sk->sk_rxhash != skb->hash)) 1068 sk->sk_rxhash = skb->hash; 1069 #endif 1070 } 1071 1072 static inline void sock_rps_reset_rxhash(struct sock *sk) 1073 { 1074 #ifdef CONFIG_RPS 1075 sk->sk_rxhash = 0; 1076 #endif 1077 } 1078 1079 #define sk_wait_event(__sk, __timeo, __condition, __wait) \ 1080 ({ int __rc; \ 1081 release_sock(__sk); \ 1082 __rc = __condition; \ 1083 if (!__rc) { \ 1084 *(__timeo) = wait_woken(__wait, \ 1085 TASK_INTERRUPTIBLE, \ 1086 *(__timeo)); \ 1087 } \ 1088 sched_annotate_sleep(); \ 1089 lock_sock(__sk); \ 1090 __rc = __condition; \ 1091 __rc; \ 1092 }) 1093 1094 int sk_stream_wait_connect(struct sock *sk, long *timeo_p); 1095 int sk_stream_wait_memory(struct sock *sk, long *timeo_p); 1096 void sk_stream_wait_close(struct sock *sk, long timeo_p); 1097 int sk_stream_error(struct sock *sk, int flags, int err); 1098 void sk_stream_kill_queues(struct sock *sk); 1099 void sk_set_memalloc(struct sock *sk); 1100 void sk_clear_memalloc(struct sock *sk); 1101 1102 void __sk_flush_backlog(struct sock *sk); 1103 1104 static inline bool sk_flush_backlog(struct sock *sk) 1105 { 1106 if (unlikely(READ_ONCE(sk->sk_backlog.tail))) { 1107 __sk_flush_backlog(sk); 1108 return true; 1109 } 1110 return false; 1111 } 1112 1113 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb); 1114 1115 struct request_sock_ops; 1116 struct timewait_sock_ops; 1117 struct inet_hashinfo; 1118 struct raw_hashinfo; 1119 struct smc_hashinfo; 1120 struct module; 1121 1122 /* 1123 * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes 1124 * un-modified. Special care is taken when initializing object to zero. 1125 */ 1126 static inline void sk_prot_clear_nulls(struct sock *sk, int size) 1127 { 1128 if (offsetof(struct sock, sk_node.next) != 0) 1129 memset(sk, 0, offsetof(struct sock, sk_node.next)); 1130 memset(&sk->sk_node.pprev, 0, 1131 size - offsetof(struct sock, sk_node.pprev)); 1132 } 1133 1134 /* Networking protocol blocks we attach to sockets. 1135 * socket layer -> transport layer interface 1136 */ 1137 struct proto { 1138 void (*close)(struct sock *sk, 1139 long timeout); 1140 int (*pre_connect)(struct sock *sk, 1141 struct sockaddr *uaddr, 1142 int addr_len); 1143 int (*connect)(struct sock *sk, 1144 struct sockaddr *uaddr, 1145 int addr_len); 1146 int (*disconnect)(struct sock *sk, int flags); 1147 1148 struct sock * (*accept)(struct sock *sk, int flags, int *err, 1149 bool kern); 1150 1151 int (*ioctl)(struct sock *sk, int cmd, 1152 unsigned long arg); 1153 int (*init)(struct sock *sk); 1154 void (*destroy)(struct sock *sk); 1155 void (*shutdown)(struct sock *sk, int how); 1156 int (*setsockopt)(struct sock *sk, int level, 1157 int optname, sockptr_t optval, 1158 unsigned int optlen); 1159 int (*getsockopt)(struct sock *sk, int level, 1160 int optname, char __user *optval, 1161 int __user *option); 1162 void (*keepalive)(struct sock *sk, int valbool); 1163 #ifdef CONFIG_COMPAT 1164 int (*compat_ioctl)(struct sock *sk, 1165 unsigned int cmd, unsigned long arg); 1166 #endif 1167 int (*sendmsg)(struct sock *sk, struct msghdr *msg, 1168 size_t len); 1169 int (*recvmsg)(struct sock *sk, struct msghdr *msg, 1170 size_t len, int noblock, int flags, 1171 int *addr_len); 1172 int (*sendpage)(struct sock *sk, struct page *page, 1173 int offset, size_t size, int flags); 1174 int (*bind)(struct sock *sk, 1175 struct sockaddr *addr, int addr_len); 1176 int (*bind_add)(struct sock *sk, 1177 struct sockaddr *addr, int addr_len); 1178 1179 int (*backlog_rcv) (struct sock *sk, 1180 struct sk_buff *skb); 1181 bool (*bpf_bypass_getsockopt)(int level, 1182 int optname); 1183 1184 void (*release_cb)(struct sock *sk); 1185 1186 /* Keeping track of sk's, looking them up, and port selection methods. */ 1187 int (*hash)(struct sock *sk); 1188 void (*unhash)(struct sock *sk); 1189 void (*rehash)(struct sock *sk); 1190 int (*get_port)(struct sock *sk, unsigned short snum); 1191 1192 /* Keeping track of sockets in use */ 1193 #ifdef CONFIG_PROC_FS 1194 unsigned int inuse_idx; 1195 #endif 1196 1197 bool (*stream_memory_free)(const struct sock *sk, int wake); 1198 bool (*stream_memory_read)(const struct sock *sk); 1199 /* Memory pressure */ 1200 void (*enter_memory_pressure)(struct sock *sk); 1201 void (*leave_memory_pressure)(struct sock *sk); 1202 atomic_long_t *memory_allocated; /* Current allocated memory. */ 1203 struct percpu_counter *sockets_allocated; /* Current number of sockets. */ 1204 /* 1205 * Pressure flag: try to collapse. 1206 * Technical note: it is used by multiple contexts non atomically. 1207 * All the __sk_mem_schedule() is of this nature: accounting 1208 * is strict, actions are advisory and have some latency. 1209 */ 1210 unsigned long *memory_pressure; 1211 long *sysctl_mem; 1212 1213 int *sysctl_wmem; 1214 int *sysctl_rmem; 1215 u32 sysctl_wmem_offset; 1216 u32 sysctl_rmem_offset; 1217 1218 int max_header; 1219 bool no_autobind; 1220 1221 struct kmem_cache *slab; 1222 unsigned int obj_size; 1223 slab_flags_t slab_flags; 1224 unsigned int useroffset; /* Usercopy region offset */ 1225 unsigned int usersize; /* Usercopy region size */ 1226 1227 struct percpu_counter *orphan_count; 1228 1229 struct request_sock_ops *rsk_prot; 1230 struct timewait_sock_ops *twsk_prot; 1231 1232 union { 1233 struct inet_hashinfo *hashinfo; 1234 struct udp_table *udp_table; 1235 struct raw_hashinfo *raw_hash; 1236 struct smc_hashinfo *smc_hash; 1237 } h; 1238 1239 struct module *owner; 1240 1241 char name[32]; 1242 1243 struct list_head node; 1244 #ifdef SOCK_REFCNT_DEBUG 1245 atomic_t socks; 1246 #endif 1247 int (*diag_destroy)(struct sock *sk, int err); 1248 } __randomize_layout; 1249 1250 int proto_register(struct proto *prot, int alloc_slab); 1251 void proto_unregister(struct proto *prot); 1252 int sock_load_diag_module(int family, int protocol); 1253 1254 #ifdef SOCK_REFCNT_DEBUG 1255 static inline void sk_refcnt_debug_inc(struct sock *sk) 1256 { 1257 atomic_inc(&sk->sk_prot->socks); 1258 } 1259 1260 static inline void sk_refcnt_debug_dec(struct sock *sk) 1261 { 1262 atomic_dec(&sk->sk_prot->socks); 1263 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n", 1264 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks)); 1265 } 1266 1267 static inline void sk_refcnt_debug_release(const struct sock *sk) 1268 { 1269 if (refcount_read(&sk->sk_refcnt) != 1) 1270 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n", 1271 sk->sk_prot->name, sk, refcount_read(&sk->sk_refcnt)); 1272 } 1273 #else /* SOCK_REFCNT_DEBUG */ 1274 #define sk_refcnt_debug_inc(sk) do { } while (0) 1275 #define sk_refcnt_debug_dec(sk) do { } while (0) 1276 #define sk_refcnt_debug_release(sk) do { } while (0) 1277 #endif /* SOCK_REFCNT_DEBUG */ 1278 1279 INDIRECT_CALLABLE_DECLARE(bool tcp_stream_memory_free(const struct sock *sk, int wake)); 1280 1281 static inline bool __sk_stream_memory_free(const struct sock *sk, int wake) 1282 { 1283 if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf)) 1284 return false; 1285 1286 #ifdef CONFIG_INET 1287 return sk->sk_prot->stream_memory_free ? 1288 INDIRECT_CALL_1(sk->sk_prot->stream_memory_free, 1289 tcp_stream_memory_free, 1290 sk, wake) : true; 1291 #else 1292 return sk->sk_prot->stream_memory_free ? 1293 sk->sk_prot->stream_memory_free(sk, wake) : true; 1294 #endif 1295 } 1296 1297 static inline bool sk_stream_memory_free(const struct sock *sk) 1298 { 1299 return __sk_stream_memory_free(sk, 0); 1300 } 1301 1302 static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake) 1303 { 1304 return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) && 1305 __sk_stream_memory_free(sk, wake); 1306 } 1307 1308 static inline bool sk_stream_is_writeable(const struct sock *sk) 1309 { 1310 return __sk_stream_is_writeable(sk, 0); 1311 } 1312 1313 static inline int sk_under_cgroup_hierarchy(struct sock *sk, 1314 struct cgroup *ancestor) 1315 { 1316 #ifdef CONFIG_SOCK_CGROUP_DATA 1317 return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data), 1318 ancestor); 1319 #else 1320 return -ENOTSUPP; 1321 #endif 1322 } 1323 1324 static inline bool sk_has_memory_pressure(const struct sock *sk) 1325 { 1326 return sk->sk_prot->memory_pressure != NULL; 1327 } 1328 1329 static inline bool sk_under_memory_pressure(const struct sock *sk) 1330 { 1331 if (!sk->sk_prot->memory_pressure) 1332 return false; 1333 1334 if (mem_cgroup_sockets_enabled && sk->sk_memcg && 1335 mem_cgroup_under_socket_pressure(sk->sk_memcg)) 1336 return true; 1337 1338 return !!*sk->sk_prot->memory_pressure; 1339 } 1340 1341 static inline long 1342 sk_memory_allocated(const struct sock *sk) 1343 { 1344 return atomic_long_read(sk->sk_prot->memory_allocated); 1345 } 1346 1347 static inline long 1348 sk_memory_allocated_add(struct sock *sk, int amt) 1349 { 1350 return atomic_long_add_return(amt, sk->sk_prot->memory_allocated); 1351 } 1352 1353 static inline void 1354 sk_memory_allocated_sub(struct sock *sk, int amt) 1355 { 1356 atomic_long_sub(amt, sk->sk_prot->memory_allocated); 1357 } 1358 1359 #define SK_ALLOC_PERCPU_COUNTER_BATCH 16 1360 1361 static inline void sk_sockets_allocated_dec(struct sock *sk) 1362 { 1363 percpu_counter_add_batch(sk->sk_prot->sockets_allocated, -1, 1364 SK_ALLOC_PERCPU_COUNTER_BATCH); 1365 } 1366 1367 static inline void sk_sockets_allocated_inc(struct sock *sk) 1368 { 1369 percpu_counter_add_batch(sk->sk_prot->sockets_allocated, 1, 1370 SK_ALLOC_PERCPU_COUNTER_BATCH); 1371 } 1372 1373 static inline u64 1374 sk_sockets_allocated_read_positive(struct sock *sk) 1375 { 1376 return percpu_counter_read_positive(sk->sk_prot->sockets_allocated); 1377 } 1378 1379 static inline int 1380 proto_sockets_allocated_sum_positive(struct proto *prot) 1381 { 1382 return percpu_counter_sum_positive(prot->sockets_allocated); 1383 } 1384 1385 static inline long 1386 proto_memory_allocated(struct proto *prot) 1387 { 1388 return atomic_long_read(prot->memory_allocated); 1389 } 1390 1391 static inline bool 1392 proto_memory_pressure(struct proto *prot) 1393 { 1394 if (!prot->memory_pressure) 1395 return false; 1396 return !!*prot->memory_pressure; 1397 } 1398 1399 1400 #ifdef CONFIG_PROC_FS 1401 /* Called with local bh disabled */ 1402 void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc); 1403 int sock_prot_inuse_get(struct net *net, struct proto *proto); 1404 int sock_inuse_get(struct net *net); 1405 #else 1406 static inline void sock_prot_inuse_add(struct net *net, struct proto *prot, 1407 int inc) 1408 { 1409 } 1410 #endif 1411 1412 1413 /* With per-bucket locks this operation is not-atomic, so that 1414 * this version is not worse. 1415 */ 1416 static inline int __sk_prot_rehash(struct sock *sk) 1417 { 1418 sk->sk_prot->unhash(sk); 1419 return sk->sk_prot->hash(sk); 1420 } 1421 1422 /* About 10 seconds */ 1423 #define SOCK_DESTROY_TIME (10*HZ) 1424 1425 /* Sockets 0-1023 can't be bound to unless you are superuser */ 1426 #define PROT_SOCK 1024 1427 1428 #define SHUTDOWN_MASK 3 1429 #define RCV_SHUTDOWN 1 1430 #define SEND_SHUTDOWN 2 1431 1432 #define SOCK_SNDBUF_LOCK 1 1433 #define SOCK_RCVBUF_LOCK 2 1434 #define SOCK_BINDADDR_LOCK 4 1435 #define SOCK_BINDPORT_LOCK 8 1436 1437 struct socket_alloc { 1438 struct socket socket; 1439 struct inode vfs_inode; 1440 }; 1441 1442 static inline struct socket *SOCKET_I(struct inode *inode) 1443 { 1444 return &container_of(inode, struct socket_alloc, vfs_inode)->socket; 1445 } 1446 1447 static inline struct inode *SOCK_INODE(struct socket *socket) 1448 { 1449 return &container_of(socket, struct socket_alloc, socket)->vfs_inode; 1450 } 1451 1452 /* 1453 * Functions for memory accounting 1454 */ 1455 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind); 1456 int __sk_mem_schedule(struct sock *sk, int size, int kind); 1457 void __sk_mem_reduce_allocated(struct sock *sk, int amount); 1458 void __sk_mem_reclaim(struct sock *sk, int amount); 1459 1460 /* We used to have PAGE_SIZE here, but systems with 64KB pages 1461 * do not necessarily have 16x time more memory than 4KB ones. 1462 */ 1463 #define SK_MEM_QUANTUM 4096 1464 #define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM) 1465 #define SK_MEM_SEND 0 1466 #define SK_MEM_RECV 1 1467 1468 /* sysctl_mem values are in pages, we convert them in SK_MEM_QUANTUM units */ 1469 static inline long sk_prot_mem_limits(const struct sock *sk, int index) 1470 { 1471 long val = sk->sk_prot->sysctl_mem[index]; 1472 1473 #if PAGE_SIZE > SK_MEM_QUANTUM 1474 val <<= PAGE_SHIFT - SK_MEM_QUANTUM_SHIFT; 1475 #elif PAGE_SIZE < SK_MEM_QUANTUM 1476 val >>= SK_MEM_QUANTUM_SHIFT - PAGE_SHIFT; 1477 #endif 1478 return val; 1479 } 1480 1481 static inline int sk_mem_pages(int amt) 1482 { 1483 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT; 1484 } 1485 1486 static inline bool sk_has_account(struct sock *sk) 1487 { 1488 /* return true if protocol supports memory accounting */ 1489 return !!sk->sk_prot->memory_allocated; 1490 } 1491 1492 static inline bool sk_wmem_schedule(struct sock *sk, int size) 1493 { 1494 if (!sk_has_account(sk)) 1495 return true; 1496 return size <= sk->sk_forward_alloc || 1497 __sk_mem_schedule(sk, size, SK_MEM_SEND); 1498 } 1499 1500 static inline bool 1501 sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size) 1502 { 1503 if (!sk_has_account(sk)) 1504 return true; 1505 return size <= sk->sk_forward_alloc || 1506 __sk_mem_schedule(sk, size, SK_MEM_RECV) || 1507 skb_pfmemalloc(skb); 1508 } 1509 1510 static inline void sk_mem_reclaim(struct sock *sk) 1511 { 1512 if (!sk_has_account(sk)) 1513 return; 1514 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM) 1515 __sk_mem_reclaim(sk, sk->sk_forward_alloc); 1516 } 1517 1518 static inline void sk_mem_reclaim_partial(struct sock *sk) 1519 { 1520 if (!sk_has_account(sk)) 1521 return; 1522 if (sk->sk_forward_alloc > SK_MEM_QUANTUM) 1523 __sk_mem_reclaim(sk, sk->sk_forward_alloc - 1); 1524 } 1525 1526 static inline void sk_mem_charge(struct sock *sk, int size) 1527 { 1528 if (!sk_has_account(sk)) 1529 return; 1530 sk->sk_forward_alloc -= size; 1531 } 1532 1533 static inline void sk_mem_uncharge(struct sock *sk, int size) 1534 { 1535 if (!sk_has_account(sk)) 1536 return; 1537 sk->sk_forward_alloc += size; 1538 1539 /* Avoid a possible overflow. 1540 * TCP send queues can make this happen, if sk_mem_reclaim() 1541 * is not called and more than 2 GBytes are released at once. 1542 * 1543 * If we reach 2 MBytes, reclaim 1 MBytes right now, there is 1544 * no need to hold that much forward allocation anyway. 1545 */ 1546 if (unlikely(sk->sk_forward_alloc >= 1 << 21)) 1547 __sk_mem_reclaim(sk, 1 << 20); 1548 } 1549 1550 DECLARE_STATIC_KEY_FALSE(tcp_tx_skb_cache_key); 1551 static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb) 1552 { 1553 sk_wmem_queued_add(sk, -skb->truesize); 1554 sk_mem_uncharge(sk, skb->truesize); 1555 if (static_branch_unlikely(&tcp_tx_skb_cache_key) && 1556 !sk->sk_tx_skb_cache && !skb_cloned(skb)) { 1557 skb_ext_reset(skb); 1558 skb_zcopy_clear(skb, true); 1559 sk->sk_tx_skb_cache = skb; 1560 return; 1561 } 1562 __kfree_skb(skb); 1563 } 1564 1565 static inline void sock_release_ownership(struct sock *sk) 1566 { 1567 if (sk->sk_lock.owned) { 1568 sk->sk_lock.owned = 0; 1569 1570 /* The sk_lock has mutex_unlock() semantics: */ 1571 mutex_release(&sk->sk_lock.dep_map, _RET_IP_); 1572 } 1573 } 1574 1575 /* 1576 * Macro so as to not evaluate some arguments when 1577 * lockdep is not enabled. 1578 * 1579 * Mark both the sk_lock and the sk_lock.slock as a 1580 * per-address-family lock class. 1581 */ 1582 #define sock_lock_init_class_and_name(sk, sname, skey, name, key) \ 1583 do { \ 1584 sk->sk_lock.owned = 0; \ 1585 init_waitqueue_head(&sk->sk_lock.wq); \ 1586 spin_lock_init(&(sk)->sk_lock.slock); \ 1587 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \ 1588 sizeof((sk)->sk_lock)); \ 1589 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \ 1590 (skey), (sname)); \ 1591 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \ 1592 } while (0) 1593 1594 static inline bool lockdep_sock_is_held(const struct sock *sk) 1595 { 1596 return lockdep_is_held(&sk->sk_lock) || 1597 lockdep_is_held(&sk->sk_lock.slock); 1598 } 1599 1600 void lock_sock_nested(struct sock *sk, int subclass); 1601 1602 static inline void lock_sock(struct sock *sk) 1603 { 1604 lock_sock_nested(sk, 0); 1605 } 1606 1607 void __lock_sock(struct sock *sk); 1608 void __release_sock(struct sock *sk); 1609 void release_sock(struct sock *sk); 1610 1611 /* BH context may only use the following locking interface. */ 1612 #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock)) 1613 #define bh_lock_sock_nested(__sk) \ 1614 spin_lock_nested(&((__sk)->sk_lock.slock), \ 1615 SINGLE_DEPTH_NESTING) 1616 #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock)) 1617 1618 bool lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock); 1619 1620 /** 1621 * unlock_sock_fast - complement of lock_sock_fast 1622 * @sk: socket 1623 * @slow: slow mode 1624 * 1625 * fast unlock socket for user context. 1626 * If slow mode is on, we call regular release_sock() 1627 */ 1628 static inline void unlock_sock_fast(struct sock *sk, bool slow) 1629 __releases(&sk->sk_lock.slock) 1630 { 1631 if (slow) { 1632 release_sock(sk); 1633 __release(&sk->sk_lock.slock); 1634 } else { 1635 spin_unlock_bh(&sk->sk_lock.slock); 1636 } 1637 } 1638 1639 /* Used by processes to "lock" a socket state, so that 1640 * interrupts and bottom half handlers won't change it 1641 * from under us. It essentially blocks any incoming 1642 * packets, so that we won't get any new data or any 1643 * packets that change the state of the socket. 1644 * 1645 * While locked, BH processing will add new packets to 1646 * the backlog queue. This queue is processed by the 1647 * owner of the socket lock right before it is released. 1648 * 1649 * Since ~2.3.5 it is also exclusive sleep lock serializing 1650 * accesses from user process context. 1651 */ 1652 1653 static inline void sock_owned_by_me(const struct sock *sk) 1654 { 1655 #ifdef CONFIG_LOCKDEP 1656 WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks); 1657 #endif 1658 } 1659 1660 static inline bool sock_owned_by_user(const struct sock *sk) 1661 { 1662 sock_owned_by_me(sk); 1663 return sk->sk_lock.owned; 1664 } 1665 1666 static inline bool sock_owned_by_user_nocheck(const struct sock *sk) 1667 { 1668 return sk->sk_lock.owned; 1669 } 1670 1671 /* no reclassification while locks are held */ 1672 static inline bool sock_allow_reclassification(const struct sock *csk) 1673 { 1674 struct sock *sk = (struct sock *)csk; 1675 1676 return !sk->sk_lock.owned && !spin_is_locked(&sk->sk_lock.slock); 1677 } 1678 1679 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 1680 struct proto *prot, int kern); 1681 void sk_free(struct sock *sk); 1682 void sk_destruct(struct sock *sk); 1683 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority); 1684 void sk_free_unlock_clone(struct sock *sk); 1685 1686 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 1687 gfp_t priority); 1688 void __sock_wfree(struct sk_buff *skb); 1689 void sock_wfree(struct sk_buff *skb); 1690 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size, 1691 gfp_t priority); 1692 void skb_orphan_partial(struct sk_buff *skb); 1693 void sock_rfree(struct sk_buff *skb); 1694 void sock_efree(struct sk_buff *skb); 1695 #ifdef CONFIG_INET 1696 void sock_edemux(struct sk_buff *skb); 1697 void sock_pfree(struct sk_buff *skb); 1698 #else 1699 #define sock_edemux sock_efree 1700 #endif 1701 1702 int sock_setsockopt(struct socket *sock, int level, int op, 1703 sockptr_t optval, unsigned int optlen); 1704 1705 int sock_getsockopt(struct socket *sock, int level, int op, 1706 char __user *optval, int __user *optlen); 1707 int sock_gettstamp(struct socket *sock, void __user *userstamp, 1708 bool timeval, bool time32); 1709 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, 1710 int noblock, int *errcode); 1711 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 1712 unsigned long data_len, int noblock, 1713 int *errcode, int max_page_order); 1714 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority); 1715 void sock_kfree_s(struct sock *sk, void *mem, int size); 1716 void sock_kzfree_s(struct sock *sk, void *mem, int size); 1717 void sk_send_sigurg(struct sock *sk); 1718 1719 struct sockcm_cookie { 1720 u64 transmit_time; 1721 u32 mark; 1722 u16 tsflags; 1723 }; 1724 1725 static inline void sockcm_init(struct sockcm_cookie *sockc, 1726 const struct sock *sk) 1727 { 1728 *sockc = (struct sockcm_cookie) { .tsflags = sk->sk_tsflags }; 1729 } 1730 1731 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg, 1732 struct sockcm_cookie *sockc); 1733 int sock_cmsg_send(struct sock *sk, struct msghdr *msg, 1734 struct sockcm_cookie *sockc); 1735 1736 /* 1737 * Functions to fill in entries in struct proto_ops when a protocol 1738 * does not implement a particular function. 1739 */ 1740 int sock_no_bind(struct socket *, struct sockaddr *, int); 1741 int sock_no_connect(struct socket *, struct sockaddr *, int, int); 1742 int sock_no_socketpair(struct socket *, struct socket *); 1743 int sock_no_accept(struct socket *, struct socket *, int, bool); 1744 int sock_no_getname(struct socket *, struct sockaddr *, int); 1745 int sock_no_ioctl(struct socket *, unsigned int, unsigned long); 1746 int sock_no_listen(struct socket *, int); 1747 int sock_no_shutdown(struct socket *, int); 1748 int sock_no_sendmsg(struct socket *, struct msghdr *, size_t); 1749 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len); 1750 int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int); 1751 int sock_no_mmap(struct file *file, struct socket *sock, 1752 struct vm_area_struct *vma); 1753 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, 1754 size_t size, int flags); 1755 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page, 1756 int offset, size_t size, int flags); 1757 1758 /* 1759 * Functions to fill in entries in struct proto_ops when a protocol 1760 * uses the inet style. 1761 */ 1762 int sock_common_getsockopt(struct socket *sock, int level, int optname, 1763 char __user *optval, int __user *optlen); 1764 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 1765 int flags); 1766 int sock_common_setsockopt(struct socket *sock, int level, int optname, 1767 sockptr_t optval, unsigned int optlen); 1768 1769 void sk_common_release(struct sock *sk); 1770 1771 /* 1772 * Default socket callbacks and setup code 1773 */ 1774 1775 /* Initialise core socket variables */ 1776 void sock_init_data(struct socket *sock, struct sock *sk); 1777 1778 /* 1779 * Socket reference counting postulates. 1780 * 1781 * * Each user of socket SHOULD hold a reference count. 1782 * * Each access point to socket (an hash table bucket, reference from a list, 1783 * running timer, skb in flight MUST hold a reference count. 1784 * * When reference count hits 0, it means it will never increase back. 1785 * * When reference count hits 0, it means that no references from 1786 * outside exist to this socket and current process on current CPU 1787 * is last user and may/should destroy this socket. 1788 * * sk_free is called from any context: process, BH, IRQ. When 1789 * it is called, socket has no references from outside -> sk_free 1790 * may release descendant resources allocated by the socket, but 1791 * to the time when it is called, socket is NOT referenced by any 1792 * hash tables, lists etc. 1793 * * Packets, delivered from outside (from network or from another process) 1794 * and enqueued on receive/error queues SHOULD NOT grab reference count, 1795 * when they sit in queue. Otherwise, packets will leak to hole, when 1796 * socket is looked up by one cpu and unhasing is made by another CPU. 1797 * It is true for udp/raw, netlink (leak to receive and error queues), tcp 1798 * (leak to backlog). Packet socket does all the processing inside 1799 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets 1800 * use separate SMP lock, so that they are prone too. 1801 */ 1802 1803 /* Ungrab socket and destroy it, if it was the last reference. */ 1804 static inline void sock_put(struct sock *sk) 1805 { 1806 if (refcount_dec_and_test(&sk->sk_refcnt)) 1807 sk_free(sk); 1808 } 1809 /* Generic version of sock_put(), dealing with all sockets 1810 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...) 1811 */ 1812 void sock_gen_put(struct sock *sk); 1813 1814 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested, 1815 unsigned int trim_cap, bool refcounted); 1816 static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb, 1817 const int nested) 1818 { 1819 return __sk_receive_skb(sk, skb, nested, 1, true); 1820 } 1821 1822 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue) 1823 { 1824 /* sk_tx_queue_mapping accept only upto a 16-bit value */ 1825 if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX)) 1826 return; 1827 sk->sk_tx_queue_mapping = tx_queue; 1828 } 1829 1830 #define NO_QUEUE_MAPPING USHRT_MAX 1831 1832 static inline void sk_tx_queue_clear(struct sock *sk) 1833 { 1834 sk->sk_tx_queue_mapping = NO_QUEUE_MAPPING; 1835 } 1836 1837 static inline int sk_tx_queue_get(const struct sock *sk) 1838 { 1839 if (sk && sk->sk_tx_queue_mapping != NO_QUEUE_MAPPING) 1840 return sk->sk_tx_queue_mapping; 1841 1842 return -1; 1843 } 1844 1845 static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb) 1846 { 1847 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 1848 if (skb_rx_queue_recorded(skb)) { 1849 u16 rx_queue = skb_get_rx_queue(skb); 1850 1851 if (WARN_ON_ONCE(rx_queue == NO_QUEUE_MAPPING)) 1852 return; 1853 1854 sk->sk_rx_queue_mapping = rx_queue; 1855 } 1856 #endif 1857 } 1858 1859 static inline void sk_rx_queue_clear(struct sock *sk) 1860 { 1861 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 1862 sk->sk_rx_queue_mapping = NO_QUEUE_MAPPING; 1863 #endif 1864 } 1865 1866 static inline int sk_rx_queue_get(const struct sock *sk) 1867 { 1868 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 1869 if (sk && sk->sk_rx_queue_mapping != NO_QUEUE_MAPPING) 1870 return sk->sk_rx_queue_mapping; 1871 #endif 1872 1873 return -1; 1874 } 1875 1876 static inline void sk_set_socket(struct sock *sk, struct socket *sock) 1877 { 1878 sk->sk_socket = sock; 1879 } 1880 1881 static inline wait_queue_head_t *sk_sleep(struct sock *sk) 1882 { 1883 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0); 1884 return &rcu_dereference_raw(sk->sk_wq)->wait; 1885 } 1886 /* Detach socket from process context. 1887 * Announce socket dead, detach it from wait queue and inode. 1888 * Note that parent inode held reference count on this struct sock, 1889 * we do not release it in this function, because protocol 1890 * probably wants some additional cleanups or even continuing 1891 * to work with this socket (TCP). 1892 */ 1893 static inline void sock_orphan(struct sock *sk) 1894 { 1895 write_lock_bh(&sk->sk_callback_lock); 1896 sock_set_flag(sk, SOCK_DEAD); 1897 sk_set_socket(sk, NULL); 1898 sk->sk_wq = NULL; 1899 write_unlock_bh(&sk->sk_callback_lock); 1900 } 1901 1902 static inline void sock_graft(struct sock *sk, struct socket *parent) 1903 { 1904 WARN_ON(parent->sk); 1905 write_lock_bh(&sk->sk_callback_lock); 1906 rcu_assign_pointer(sk->sk_wq, &parent->wq); 1907 parent->sk = sk; 1908 sk_set_socket(sk, parent); 1909 sk->sk_uid = SOCK_INODE(parent)->i_uid; 1910 security_sock_graft(sk, parent); 1911 write_unlock_bh(&sk->sk_callback_lock); 1912 } 1913 1914 kuid_t sock_i_uid(struct sock *sk); 1915 unsigned long sock_i_ino(struct sock *sk); 1916 1917 static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk) 1918 { 1919 return sk ? sk->sk_uid : make_kuid(net->user_ns, 0); 1920 } 1921 1922 static inline u32 net_tx_rndhash(void) 1923 { 1924 u32 v = prandom_u32(); 1925 1926 return v ?: 1; 1927 } 1928 1929 static inline void sk_set_txhash(struct sock *sk) 1930 { 1931 sk->sk_txhash = net_tx_rndhash(); 1932 } 1933 1934 static inline bool sk_rethink_txhash(struct sock *sk) 1935 { 1936 if (sk->sk_txhash) { 1937 sk_set_txhash(sk); 1938 return true; 1939 } 1940 return false; 1941 } 1942 1943 static inline struct dst_entry * 1944 __sk_dst_get(struct sock *sk) 1945 { 1946 return rcu_dereference_check(sk->sk_dst_cache, 1947 lockdep_sock_is_held(sk)); 1948 } 1949 1950 static inline struct dst_entry * 1951 sk_dst_get(struct sock *sk) 1952 { 1953 struct dst_entry *dst; 1954 1955 rcu_read_lock(); 1956 dst = rcu_dereference(sk->sk_dst_cache); 1957 if (dst && !atomic_inc_not_zero(&dst->__refcnt)) 1958 dst = NULL; 1959 rcu_read_unlock(); 1960 return dst; 1961 } 1962 1963 static inline void __dst_negative_advice(struct sock *sk) 1964 { 1965 struct dst_entry *ndst, *dst = __sk_dst_get(sk); 1966 1967 if (dst && dst->ops->negative_advice) { 1968 ndst = dst->ops->negative_advice(dst); 1969 1970 if (ndst != dst) { 1971 rcu_assign_pointer(sk->sk_dst_cache, ndst); 1972 sk_tx_queue_clear(sk); 1973 sk->sk_dst_pending_confirm = 0; 1974 } 1975 } 1976 } 1977 1978 static inline void dst_negative_advice(struct sock *sk) 1979 { 1980 sk_rethink_txhash(sk); 1981 __dst_negative_advice(sk); 1982 } 1983 1984 static inline void 1985 __sk_dst_set(struct sock *sk, struct dst_entry *dst) 1986 { 1987 struct dst_entry *old_dst; 1988 1989 sk_tx_queue_clear(sk); 1990 sk->sk_dst_pending_confirm = 0; 1991 old_dst = rcu_dereference_protected(sk->sk_dst_cache, 1992 lockdep_sock_is_held(sk)); 1993 rcu_assign_pointer(sk->sk_dst_cache, dst); 1994 dst_release(old_dst); 1995 } 1996 1997 static inline void 1998 sk_dst_set(struct sock *sk, struct dst_entry *dst) 1999 { 2000 struct dst_entry *old_dst; 2001 2002 sk_tx_queue_clear(sk); 2003 sk->sk_dst_pending_confirm = 0; 2004 old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst); 2005 dst_release(old_dst); 2006 } 2007 2008 static inline void 2009 __sk_dst_reset(struct sock *sk) 2010 { 2011 __sk_dst_set(sk, NULL); 2012 } 2013 2014 static inline void 2015 sk_dst_reset(struct sock *sk) 2016 { 2017 sk_dst_set(sk, NULL); 2018 } 2019 2020 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie); 2021 2022 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie); 2023 2024 static inline void sk_dst_confirm(struct sock *sk) 2025 { 2026 if (!READ_ONCE(sk->sk_dst_pending_confirm)) 2027 WRITE_ONCE(sk->sk_dst_pending_confirm, 1); 2028 } 2029 2030 static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n) 2031 { 2032 if (skb_get_dst_pending_confirm(skb)) { 2033 struct sock *sk = skb->sk; 2034 unsigned long now = jiffies; 2035 2036 /* avoid dirtying neighbour */ 2037 if (READ_ONCE(n->confirmed) != now) 2038 WRITE_ONCE(n->confirmed, now); 2039 if (sk && READ_ONCE(sk->sk_dst_pending_confirm)) 2040 WRITE_ONCE(sk->sk_dst_pending_confirm, 0); 2041 } 2042 } 2043 2044 bool sk_mc_loop(struct sock *sk); 2045 2046 static inline bool sk_can_gso(const struct sock *sk) 2047 { 2048 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type); 2049 } 2050 2051 void sk_setup_caps(struct sock *sk, struct dst_entry *dst); 2052 2053 static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags) 2054 { 2055 sk->sk_route_nocaps |= flags; 2056 sk->sk_route_caps &= ~flags; 2057 } 2058 2059 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb, 2060 struct iov_iter *from, char *to, 2061 int copy, int offset) 2062 { 2063 if (skb->ip_summed == CHECKSUM_NONE) { 2064 __wsum csum = 0; 2065 if (!csum_and_copy_from_iter_full(to, copy, &csum, from)) 2066 return -EFAULT; 2067 skb->csum = csum_block_add(skb->csum, csum, offset); 2068 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) { 2069 if (!copy_from_iter_full_nocache(to, copy, from)) 2070 return -EFAULT; 2071 } else if (!copy_from_iter_full(to, copy, from)) 2072 return -EFAULT; 2073 2074 return 0; 2075 } 2076 2077 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb, 2078 struct iov_iter *from, int copy) 2079 { 2080 int err, offset = skb->len; 2081 2082 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy), 2083 copy, offset); 2084 if (err) 2085 __skb_trim(skb, offset); 2086 2087 return err; 2088 } 2089 2090 static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from, 2091 struct sk_buff *skb, 2092 struct page *page, 2093 int off, int copy) 2094 { 2095 int err; 2096 2097 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off, 2098 copy, skb->len); 2099 if (err) 2100 return err; 2101 2102 skb->len += copy; 2103 skb->data_len += copy; 2104 skb->truesize += copy; 2105 sk_wmem_queued_add(sk, copy); 2106 sk_mem_charge(sk, copy); 2107 return 0; 2108 } 2109 2110 /** 2111 * sk_wmem_alloc_get - returns write allocations 2112 * @sk: socket 2113 * 2114 * Return: sk_wmem_alloc minus initial offset of one 2115 */ 2116 static inline int sk_wmem_alloc_get(const struct sock *sk) 2117 { 2118 return refcount_read(&sk->sk_wmem_alloc) - 1; 2119 } 2120 2121 /** 2122 * sk_rmem_alloc_get - returns read allocations 2123 * @sk: socket 2124 * 2125 * Return: sk_rmem_alloc 2126 */ 2127 static inline int sk_rmem_alloc_get(const struct sock *sk) 2128 { 2129 return atomic_read(&sk->sk_rmem_alloc); 2130 } 2131 2132 /** 2133 * sk_has_allocations - check if allocations are outstanding 2134 * @sk: socket 2135 * 2136 * Return: true if socket has write or read allocations 2137 */ 2138 static inline bool sk_has_allocations(const struct sock *sk) 2139 { 2140 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk); 2141 } 2142 2143 /** 2144 * skwq_has_sleeper - check if there are any waiting processes 2145 * @wq: struct socket_wq 2146 * 2147 * Return: true if socket_wq has waiting processes 2148 * 2149 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory 2150 * barrier call. They were added due to the race found within the tcp code. 2151 * 2152 * Consider following tcp code paths:: 2153 * 2154 * CPU1 CPU2 2155 * sys_select receive packet 2156 * ... ... 2157 * __add_wait_queue update tp->rcv_nxt 2158 * ... ... 2159 * tp->rcv_nxt check sock_def_readable 2160 * ... { 2161 * schedule rcu_read_lock(); 2162 * wq = rcu_dereference(sk->sk_wq); 2163 * if (wq && waitqueue_active(&wq->wait)) 2164 * wake_up_interruptible(&wq->wait) 2165 * ... 2166 * } 2167 * 2168 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay 2169 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1 2170 * could then endup calling schedule and sleep forever if there are no more 2171 * data on the socket. 2172 * 2173 */ 2174 static inline bool skwq_has_sleeper(struct socket_wq *wq) 2175 { 2176 return wq && wq_has_sleeper(&wq->wait); 2177 } 2178 2179 /** 2180 * sock_poll_wait - place memory barrier behind the poll_wait call. 2181 * @filp: file 2182 * @sock: socket to wait on 2183 * @p: poll_table 2184 * 2185 * See the comments in the wq_has_sleeper function. 2186 */ 2187 static inline void sock_poll_wait(struct file *filp, struct socket *sock, 2188 poll_table *p) 2189 { 2190 if (!poll_does_not_wait(p)) { 2191 poll_wait(filp, &sock->wq.wait, p); 2192 /* We need to be sure we are in sync with the 2193 * socket flags modification. 2194 * 2195 * This memory barrier is paired in the wq_has_sleeper. 2196 */ 2197 smp_mb(); 2198 } 2199 } 2200 2201 static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk) 2202 { 2203 if (sk->sk_txhash) { 2204 skb->l4_hash = 1; 2205 skb->hash = sk->sk_txhash; 2206 } 2207 } 2208 2209 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk); 2210 2211 /* 2212 * Queue a received datagram if it will fit. Stream and sequenced 2213 * protocols can't normally use this as they need to fit buffers in 2214 * and play with them. 2215 * 2216 * Inlined as it's very short and called for pretty much every 2217 * packet ever received. 2218 */ 2219 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk) 2220 { 2221 skb_orphan(skb); 2222 skb->sk = sk; 2223 skb->destructor = sock_rfree; 2224 atomic_add(skb->truesize, &sk->sk_rmem_alloc); 2225 sk_mem_charge(sk, skb->truesize); 2226 } 2227 2228 static inline void skb_set_owner_sk_safe(struct sk_buff *skb, struct sock *sk) 2229 { 2230 if (sk && refcount_inc_not_zero(&sk->sk_refcnt)) { 2231 skb_orphan(skb); 2232 skb->destructor = sock_efree; 2233 skb->sk = sk; 2234 } 2235 } 2236 2237 void sk_reset_timer(struct sock *sk, struct timer_list *timer, 2238 unsigned long expires); 2239 2240 void sk_stop_timer(struct sock *sk, struct timer_list *timer); 2241 2242 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer); 2243 2244 int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue, 2245 struct sk_buff *skb, unsigned int flags, 2246 void (*destructor)(struct sock *sk, 2247 struct sk_buff *skb)); 2248 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); 2249 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); 2250 2251 int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb); 2252 struct sk_buff *sock_dequeue_err_skb(struct sock *sk); 2253 2254 /* 2255 * Recover an error report and clear atomically 2256 */ 2257 2258 static inline int sock_error(struct sock *sk) 2259 { 2260 int err; 2261 if (likely(!sk->sk_err)) 2262 return 0; 2263 err = xchg(&sk->sk_err, 0); 2264 return -err; 2265 } 2266 2267 static inline unsigned long sock_wspace(struct sock *sk) 2268 { 2269 int amt = 0; 2270 2271 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { 2272 amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc); 2273 if (amt < 0) 2274 amt = 0; 2275 } 2276 return amt; 2277 } 2278 2279 /* Note: 2280 * We use sk->sk_wq_raw, from contexts knowing this 2281 * pointer is not NULL and cannot disappear/change. 2282 */ 2283 static inline void sk_set_bit(int nr, struct sock *sk) 2284 { 2285 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) && 2286 !sock_flag(sk, SOCK_FASYNC)) 2287 return; 2288 2289 set_bit(nr, &sk->sk_wq_raw->flags); 2290 } 2291 2292 static inline void sk_clear_bit(int nr, struct sock *sk) 2293 { 2294 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) && 2295 !sock_flag(sk, SOCK_FASYNC)) 2296 return; 2297 2298 clear_bit(nr, &sk->sk_wq_raw->flags); 2299 } 2300 2301 static inline void sk_wake_async(const struct sock *sk, int how, int band) 2302 { 2303 if (sock_flag(sk, SOCK_FASYNC)) { 2304 rcu_read_lock(); 2305 sock_wake_async(rcu_dereference(sk->sk_wq), how, band); 2306 rcu_read_unlock(); 2307 } 2308 } 2309 2310 /* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might 2311 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak. 2312 * Note: for send buffers, TCP works better if we can build two skbs at 2313 * minimum. 2314 */ 2315 #define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff))) 2316 2317 #define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2) 2318 #define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE 2319 2320 static inline void sk_stream_moderate_sndbuf(struct sock *sk) 2321 { 2322 u32 val; 2323 2324 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) 2325 return; 2326 2327 val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1); 2328 2329 WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF)); 2330 } 2331 2332 struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp, 2333 bool force_schedule); 2334 2335 /** 2336 * sk_page_frag - return an appropriate page_frag 2337 * @sk: socket 2338 * 2339 * Use the per task page_frag instead of the per socket one for 2340 * optimization when we know that we're in the normal context and owns 2341 * everything that's associated with %current. 2342 * 2343 * gfpflags_allow_blocking() isn't enough here as direct reclaim may nest 2344 * inside other socket operations and end up recursing into sk_page_frag() 2345 * while it's already in use. 2346 * 2347 * Return: a per task page_frag if context allows that, 2348 * otherwise a per socket one. 2349 */ 2350 static inline struct page_frag *sk_page_frag(struct sock *sk) 2351 { 2352 if (gfpflags_normal_context(sk->sk_allocation)) 2353 return ¤t->task_frag; 2354 2355 return &sk->sk_frag; 2356 } 2357 2358 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag); 2359 2360 /* 2361 * Default write policy as shown to user space via poll/select/SIGIO 2362 */ 2363 static inline bool sock_writeable(const struct sock *sk) 2364 { 2365 return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1); 2366 } 2367 2368 static inline gfp_t gfp_any(void) 2369 { 2370 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL; 2371 } 2372 2373 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock) 2374 { 2375 return noblock ? 0 : sk->sk_rcvtimeo; 2376 } 2377 2378 static inline long sock_sndtimeo(const struct sock *sk, bool noblock) 2379 { 2380 return noblock ? 0 : sk->sk_sndtimeo; 2381 } 2382 2383 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len) 2384 { 2385 int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len); 2386 2387 return v ?: 1; 2388 } 2389 2390 /* Alas, with timeout socket operations are not restartable. 2391 * Compare this to poll(). 2392 */ 2393 static inline int sock_intr_errno(long timeo) 2394 { 2395 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR; 2396 } 2397 2398 struct sock_skb_cb { 2399 u32 dropcount; 2400 }; 2401 2402 /* Store sock_skb_cb at the end of skb->cb[] so protocol families 2403 * using skb->cb[] would keep using it directly and utilize its 2404 * alignement guarantee. 2405 */ 2406 #define SOCK_SKB_CB_OFFSET ((sizeof_field(struct sk_buff, cb) - \ 2407 sizeof(struct sock_skb_cb))) 2408 2409 #define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \ 2410 SOCK_SKB_CB_OFFSET)) 2411 2412 #define sock_skb_cb_check_size(size) \ 2413 BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET) 2414 2415 static inline void 2416 sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb) 2417 { 2418 SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ? 2419 atomic_read(&sk->sk_drops) : 0; 2420 } 2421 2422 static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb) 2423 { 2424 int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs); 2425 2426 atomic_add(segs, &sk->sk_drops); 2427 } 2428 2429 static inline ktime_t sock_read_timestamp(struct sock *sk) 2430 { 2431 #if BITS_PER_LONG==32 2432 unsigned int seq; 2433 ktime_t kt; 2434 2435 do { 2436 seq = read_seqbegin(&sk->sk_stamp_seq); 2437 kt = sk->sk_stamp; 2438 } while (read_seqretry(&sk->sk_stamp_seq, seq)); 2439 2440 return kt; 2441 #else 2442 return READ_ONCE(sk->sk_stamp); 2443 #endif 2444 } 2445 2446 static inline void sock_write_timestamp(struct sock *sk, ktime_t kt) 2447 { 2448 #if BITS_PER_LONG==32 2449 write_seqlock(&sk->sk_stamp_seq); 2450 sk->sk_stamp = kt; 2451 write_sequnlock(&sk->sk_stamp_seq); 2452 #else 2453 WRITE_ONCE(sk->sk_stamp, kt); 2454 #endif 2455 } 2456 2457 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk, 2458 struct sk_buff *skb); 2459 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk, 2460 struct sk_buff *skb); 2461 2462 static inline void 2463 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb) 2464 { 2465 ktime_t kt = skb->tstamp; 2466 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb); 2467 2468 /* 2469 * generate control messages if 2470 * - receive time stamping in software requested 2471 * - software time stamp available and wanted 2472 * - hardware time stamps available and wanted 2473 */ 2474 if (sock_flag(sk, SOCK_RCVTSTAMP) || 2475 (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) || 2476 (kt && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) || 2477 (hwtstamps->hwtstamp && 2478 (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE))) 2479 __sock_recv_timestamp(msg, sk, skb); 2480 else 2481 sock_write_timestamp(sk, kt); 2482 2483 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid) 2484 __sock_recv_wifi_status(msg, sk, skb); 2485 } 2486 2487 void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk, 2488 struct sk_buff *skb); 2489 2490 #define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC) 2491 static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk, 2492 struct sk_buff *skb) 2493 { 2494 #define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \ 2495 (1UL << SOCK_RCVTSTAMP)) 2496 #define TSFLAGS_ANY (SOF_TIMESTAMPING_SOFTWARE | \ 2497 SOF_TIMESTAMPING_RAW_HARDWARE) 2498 2499 if (sk->sk_flags & FLAGS_TS_OR_DROPS || sk->sk_tsflags & TSFLAGS_ANY) 2500 __sock_recv_ts_and_drops(msg, sk, skb); 2501 else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP))) 2502 sock_write_timestamp(sk, skb->tstamp); 2503 else if (unlikely(sk->sk_stamp == SK_DEFAULT_STAMP)) 2504 sock_write_timestamp(sk, 0); 2505 } 2506 2507 void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags); 2508 2509 /** 2510 * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped 2511 * @sk: socket sending this packet 2512 * @tsflags: timestamping flags to use 2513 * @tx_flags: completed with instructions for time stamping 2514 * @tskey: filled in with next sk_tskey (not for TCP, which uses seqno) 2515 * 2516 * Note: callers should take care of initial ``*tx_flags`` value (usually 0) 2517 */ 2518 static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags, 2519 __u8 *tx_flags, __u32 *tskey) 2520 { 2521 if (unlikely(tsflags)) { 2522 __sock_tx_timestamp(tsflags, tx_flags); 2523 if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey && 2524 tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK) 2525 *tskey = sk->sk_tskey++; 2526 } 2527 if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS))) 2528 *tx_flags |= SKBTX_WIFI_STATUS; 2529 } 2530 2531 static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags, 2532 __u8 *tx_flags) 2533 { 2534 _sock_tx_timestamp(sk, tsflags, tx_flags, NULL); 2535 } 2536 2537 static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags) 2538 { 2539 _sock_tx_timestamp(skb->sk, tsflags, &skb_shinfo(skb)->tx_flags, 2540 &skb_shinfo(skb)->tskey); 2541 } 2542 2543 DECLARE_STATIC_KEY_FALSE(tcp_rx_skb_cache_key); 2544 /** 2545 * sk_eat_skb - Release a skb if it is no longer needed 2546 * @sk: socket to eat this skb from 2547 * @skb: socket buffer to eat 2548 * 2549 * This routine must be called with interrupts disabled or with the socket 2550 * locked so that the sk_buff queue operation is ok. 2551 */ 2552 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb) 2553 { 2554 __skb_unlink(skb, &sk->sk_receive_queue); 2555 if (static_branch_unlikely(&tcp_rx_skb_cache_key) && 2556 !sk->sk_rx_skb_cache) { 2557 sk->sk_rx_skb_cache = skb; 2558 skb_orphan(skb); 2559 return; 2560 } 2561 __kfree_skb(skb); 2562 } 2563 2564 static inline 2565 struct net *sock_net(const struct sock *sk) 2566 { 2567 return read_pnet(&sk->sk_net); 2568 } 2569 2570 static inline 2571 void sock_net_set(struct sock *sk, struct net *net) 2572 { 2573 write_pnet(&sk->sk_net, net); 2574 } 2575 2576 static inline bool 2577 skb_sk_is_prefetched(struct sk_buff *skb) 2578 { 2579 #ifdef CONFIG_INET 2580 return skb->destructor == sock_pfree; 2581 #else 2582 return false; 2583 #endif /* CONFIG_INET */ 2584 } 2585 2586 /* This helper checks if a socket is a full socket, 2587 * ie _not_ a timewait or request socket. 2588 */ 2589 static inline bool sk_fullsock(const struct sock *sk) 2590 { 2591 return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV); 2592 } 2593 2594 static inline bool 2595 sk_is_refcounted(struct sock *sk) 2596 { 2597 /* Only full sockets have sk->sk_flags. */ 2598 return !sk_fullsock(sk) || !sock_flag(sk, SOCK_RCU_FREE); 2599 } 2600 2601 /** 2602 * skb_steal_sock - steal a socket from an sk_buff 2603 * @skb: sk_buff to steal the socket from 2604 * @refcounted: is set to true if the socket is reference-counted 2605 */ 2606 static inline struct sock * 2607 skb_steal_sock(struct sk_buff *skb, bool *refcounted) 2608 { 2609 if (skb->sk) { 2610 struct sock *sk = skb->sk; 2611 2612 *refcounted = true; 2613 if (skb_sk_is_prefetched(skb)) 2614 *refcounted = sk_is_refcounted(sk); 2615 skb->destructor = NULL; 2616 skb->sk = NULL; 2617 return sk; 2618 } 2619 *refcounted = false; 2620 return NULL; 2621 } 2622 2623 /* Checks if this SKB belongs to an HW offloaded socket 2624 * and whether any SW fallbacks are required based on dev. 2625 * Check decrypted mark in case skb_orphan() cleared socket. 2626 */ 2627 static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb, 2628 struct net_device *dev) 2629 { 2630 #ifdef CONFIG_SOCK_VALIDATE_XMIT 2631 struct sock *sk = skb->sk; 2632 2633 if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) { 2634 skb = sk->sk_validate_xmit_skb(sk, dev, skb); 2635 #ifdef CONFIG_TLS_DEVICE 2636 } else if (unlikely(skb->decrypted)) { 2637 pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n"); 2638 kfree_skb(skb); 2639 skb = NULL; 2640 #endif 2641 } 2642 #endif 2643 2644 return skb; 2645 } 2646 2647 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV 2648 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE) 2649 */ 2650 static inline bool sk_listener(const struct sock *sk) 2651 { 2652 return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV); 2653 } 2654 2655 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag); 2656 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level, 2657 int type); 2658 2659 bool sk_ns_capable(const struct sock *sk, 2660 struct user_namespace *user_ns, int cap); 2661 bool sk_capable(const struct sock *sk, int cap); 2662 bool sk_net_capable(const struct sock *sk, int cap); 2663 2664 void sk_get_meminfo(const struct sock *sk, u32 *meminfo); 2665 2666 /* Take into consideration the size of the struct sk_buff overhead in the 2667 * determination of these values, since that is non-constant across 2668 * platforms. This makes socket queueing behavior and performance 2669 * not depend upon such differences. 2670 */ 2671 #define _SK_MEM_PACKETS 256 2672 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256) 2673 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 2674 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 2675 2676 extern __u32 sysctl_wmem_max; 2677 extern __u32 sysctl_rmem_max; 2678 2679 extern int sysctl_tstamp_allow_data; 2680 extern int sysctl_optmem_max; 2681 2682 extern __u32 sysctl_wmem_default; 2683 extern __u32 sysctl_rmem_default; 2684 2685 DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key); 2686 2687 static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto) 2688 { 2689 /* Does this proto have per netns sysctl_wmem ? */ 2690 if (proto->sysctl_wmem_offset) 2691 return *(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset); 2692 2693 return *proto->sysctl_wmem; 2694 } 2695 2696 static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto) 2697 { 2698 /* Does this proto have per netns sysctl_rmem ? */ 2699 if (proto->sysctl_rmem_offset) 2700 return *(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset); 2701 2702 return *proto->sysctl_rmem; 2703 } 2704 2705 /* Default TCP Small queue budget is ~1 ms of data (1sec >> 10) 2706 * Some wifi drivers need to tweak it to get more chunks. 2707 * They can use this helper from their ndo_start_xmit() 2708 */ 2709 static inline void sk_pacing_shift_update(struct sock *sk, int val) 2710 { 2711 if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val) 2712 return; 2713 WRITE_ONCE(sk->sk_pacing_shift, val); 2714 } 2715 2716 /* if a socket is bound to a device, check that the given device 2717 * index is either the same or that the socket is bound to an L3 2718 * master device and the given device index is also enslaved to 2719 * that L3 master 2720 */ 2721 static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif) 2722 { 2723 int mdif; 2724 2725 if (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dif) 2726 return true; 2727 2728 mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif); 2729 if (mdif && mdif == sk->sk_bound_dev_if) 2730 return true; 2731 2732 return false; 2733 } 2734 2735 void sock_def_readable(struct sock *sk); 2736 2737 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk); 2738 void sock_enable_timestamps(struct sock *sk); 2739 void sock_no_linger(struct sock *sk); 2740 void sock_set_keepalive(struct sock *sk); 2741 void sock_set_priority(struct sock *sk, u32 priority); 2742 void sock_set_rcvbuf(struct sock *sk, int val); 2743 void sock_set_mark(struct sock *sk, u32 val); 2744 void sock_set_reuseaddr(struct sock *sk); 2745 void sock_set_reuseport(struct sock *sk); 2746 void sock_set_sndtimeo(struct sock *sk, s64 secs); 2747 2748 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len); 2749 2750 #endif /* _SOCK_H */ 2751