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