1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* 3 * INET An implementation of the TCP/IP protocol suite for the LINUX 4 * operating system. INET is implemented using the BSD Socket 5 * interface as the means of communication with the user level. 6 * 7 * Definitions for the AF_INET socket handler. 8 * 9 * Version: @(#)sock.h 1.0.4 05/13/93 10 * 11 * Authors: Ross Biro 12 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 13 * Corey Minyard <wf-rch!minyard@relay.EU.net> 14 * Florian La Roche <flla@stud.uni-sb.de> 15 * 16 * Fixes: 17 * Alan Cox : Volatiles in skbuff pointers. See 18 * skbuff comments. May be overdone, 19 * better to prove they can be removed 20 * than the reverse. 21 * Alan Cox : Added a zapped field for tcp to note 22 * a socket is reset and must stay shut up 23 * Alan Cox : New fields for options 24 * Pauline Middelink : identd support 25 * Alan Cox : Eliminate low level recv/recvfrom 26 * David S. Miller : New socket lookup architecture. 27 * Steve Whitehouse: Default routines for sock_ops 28 * Arnaldo C. Melo : removed net_pinfo, tp_pinfo and made 29 * protinfo be just a void pointer, as the 30 * protocol specific parts were moved to 31 * respective headers and ipv4/v6, etc now 32 * use private slabcaches for its socks 33 * Pedro Hortas : New flags field for socket options 34 */ 35 #ifndef _SOCK_H 36 #define _SOCK_H 37 38 #include <linux/hardirq.h> 39 #include <linux/kernel.h> 40 #include <linux/list.h> 41 #include <linux/list_nulls.h> 42 #include <linux/timer.h> 43 #include <linux/cache.h> 44 #include <linux/bitops.h> 45 #include <linux/lockdep.h> 46 #include <linux/netdevice.h> 47 #include <linux/skbuff.h> /* struct sk_buff */ 48 #include <linux/mm.h> 49 #include <linux/security.h> 50 #include <linux/slab.h> 51 #include <linux/uaccess.h> 52 #include <linux/page_counter.h> 53 #include <linux/memcontrol.h> 54 #include <linux/static_key.h> 55 #include <linux/sched.h> 56 #include <linux/wait.h> 57 #include <linux/cgroup-defs.h> 58 #include <linux/rbtree.h> 59 #include <linux/filter.h> 60 #include <linux/rculist_nulls.h> 61 #include <linux/poll.h> 62 63 #include <linux/atomic.h> 64 #include <linux/refcount.h> 65 #include <net/dst.h> 66 #include <net/checksum.h> 67 #include <net/tcp_states.h> 68 #include <linux/net_tstamp.h> 69 #include <net/smc.h> 70 #include <net/l3mdev.h> 71 72 /* 73 * This structure really needs to be cleaned up. 74 * Most of it is for TCP, and not used by any of 75 * the other protocols. 76 */ 77 78 /* Define this to get the SOCK_DBG debugging facility. */ 79 #define SOCK_DEBUGGING 80 #ifdef SOCK_DEBUGGING 81 #define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \ 82 printk(KERN_DEBUG msg); } while (0) 83 #else 84 /* Validate arguments and do nothing */ 85 static inline __printf(2, 3) 86 void SOCK_DEBUG(const struct sock *sk, const char *msg, ...) 87 { 88 } 89 #endif 90 91 /* This is the per-socket lock. The spinlock provides a synchronization 92 * between user contexts and software interrupt processing, whereas the 93 * mini-semaphore synchronizes multiple users amongst themselves. 94 */ 95 typedef struct { 96 spinlock_t slock; 97 int owned; 98 wait_queue_head_t wq; 99 /* 100 * We express the mutex-alike socket_lock semantics 101 * to the lock validator by explicitly managing 102 * the slock as a lock variant (in addition to 103 * the slock itself): 104 */ 105 #ifdef CONFIG_DEBUG_LOCK_ALLOC 106 struct lockdep_map dep_map; 107 #endif 108 } socket_lock_t; 109 110 struct sock; 111 struct proto; 112 struct net; 113 114 typedef __u32 __bitwise __portpair; 115 typedef __u64 __bitwise __addrpair; 116 117 /** 118 * struct sock_common - minimal network layer representation of sockets 119 * @skc_daddr: Foreign IPv4 addr 120 * @skc_rcv_saddr: Bound local IPv4 addr 121 * @skc_hash: hash value used with various protocol lookup tables 122 * @skc_u16hashes: two u16 hash values used by UDP lookup tables 123 * @skc_dport: placeholder for inet_dport/tw_dport 124 * @skc_num: placeholder for inet_num/tw_num 125 * @skc_family: network address family 126 * @skc_state: Connection state 127 * @skc_reuse: %SO_REUSEADDR setting 128 * @skc_reuseport: %SO_REUSEPORT setting 129 * @skc_bound_dev_if: bound device index if != 0 130 * @skc_bind_node: bind hash linkage for various protocol lookup tables 131 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol 132 * @skc_prot: protocol handlers inside a network family 133 * @skc_net: reference to the network namespace of this socket 134 * @skc_node: main hash linkage for various protocol lookup tables 135 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol 136 * @skc_tx_queue_mapping: tx queue number for this connection 137 * @skc_rx_queue_mapping: rx queue number for this connection 138 * @skc_flags: place holder for sk_flags 139 * %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE, 140 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings 141 * @skc_incoming_cpu: record/match cpu processing incoming packets 142 * @skc_refcnt: reference count 143 * 144 * This is the minimal network layer representation of sockets, the header 145 * for struct sock and struct inet_timewait_sock. 146 */ 147 struct sock_common { 148 /* skc_daddr and skc_rcv_saddr must be grouped on a 8 bytes aligned 149 * address on 64bit arches : cf INET_MATCH() 150 */ 151 union { 152 __addrpair skc_addrpair; 153 struct { 154 __be32 skc_daddr; 155 __be32 skc_rcv_saddr; 156 }; 157 }; 158 union { 159 unsigned int skc_hash; 160 __u16 skc_u16hashes[2]; 161 }; 162 /* skc_dport && skc_num must be grouped as well */ 163 union { 164 __portpair skc_portpair; 165 struct { 166 __be16 skc_dport; 167 __u16 skc_num; 168 }; 169 }; 170 171 unsigned short skc_family; 172 volatile unsigned char skc_state; 173 unsigned char skc_reuse:4; 174 unsigned char skc_reuseport:1; 175 unsigned char skc_ipv6only:1; 176 unsigned char skc_net_refcnt:1; 177 int skc_bound_dev_if; 178 union { 179 struct hlist_node skc_bind_node; 180 struct hlist_node skc_portaddr_node; 181 }; 182 struct proto *skc_prot; 183 possible_net_t skc_net; 184 185 #if IS_ENABLED(CONFIG_IPV6) 186 struct in6_addr skc_v6_daddr; 187 struct in6_addr skc_v6_rcv_saddr; 188 #endif 189 190 atomic64_t skc_cookie; 191 192 /* following fields are padding to force 193 * offset(struct sock, sk_refcnt) == 128 on 64bit arches 194 * assuming IPV6 is enabled. We use this padding differently 195 * for different kind of 'sockets' 196 */ 197 union { 198 unsigned long skc_flags; 199 struct sock *skc_listener; /* request_sock */ 200 struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */ 201 }; 202 /* 203 * fields between dontcopy_begin/dontcopy_end 204 * are not copied in sock_copy() 205 */ 206 /* private: */ 207 int skc_dontcopy_begin[0]; 208 /* public: */ 209 union { 210 struct hlist_node skc_node; 211 struct hlist_nulls_node skc_nulls_node; 212 }; 213 unsigned short skc_tx_queue_mapping; 214 #ifdef CONFIG_XPS 215 unsigned short skc_rx_queue_mapping; 216 #endif 217 union { 218 int skc_incoming_cpu; 219 u32 skc_rcv_wnd; 220 u32 skc_tw_rcv_nxt; /* struct tcp_timewait_sock */ 221 }; 222 223 refcount_t skc_refcnt; 224 /* private: */ 225 int skc_dontcopy_end[0]; 226 union { 227 u32 skc_rxhash; 228 u32 skc_window_clamp; 229 u32 skc_tw_snd_nxt; /* struct tcp_timewait_sock */ 230 }; 231 /* public: */ 232 }; 233 234 struct bpf_sk_storage; 235 236 /** 237 * struct sock - network layer representation of sockets 238 * @__sk_common: shared layout with inet_timewait_sock 239 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN 240 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings 241 * @sk_lock: synchronizer 242 * @sk_kern_sock: True if sock is using kernel lock classes 243 * @sk_rcvbuf: size of receive buffer in bytes 244 * @sk_wq: sock wait queue and async head 245 * @sk_rx_dst: receive input route used by early demux 246 * @sk_dst_cache: destination cache 247 * @sk_dst_pending_confirm: need to confirm neighbour 248 * @sk_policy: flow policy 249 * @sk_receive_queue: incoming packets 250 * @sk_wmem_alloc: transmit queue bytes committed 251 * @sk_tsq_flags: TCP Small Queues flags 252 * @sk_write_queue: Packet sending queue 253 * @sk_omem_alloc: "o" is "option" or "other" 254 * @sk_wmem_queued: persistent queue size 255 * @sk_forward_alloc: space allocated forward 256 * @sk_napi_id: id of the last napi context to receive data for sk 257 * @sk_ll_usec: usecs to busypoll when there is no data 258 * @sk_allocation: allocation mode 259 * @sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler) 260 * @sk_pacing_status: Pacing status (requested, handled by sch_fq) 261 * @sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE) 262 * @sk_sndbuf: size of send buffer in bytes 263 * @__sk_flags_offset: empty field used to determine location of bitfield 264 * @sk_padding: unused element for alignment 265 * @sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets 266 * @sk_no_check_rx: allow zero checksum in RX packets 267 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO) 268 * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK) 269 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4) 270 * @sk_gso_max_size: Maximum GSO segment size to build 271 * @sk_gso_max_segs: Maximum number of GSO segments 272 * @sk_pacing_shift: scaling factor for TCP Small Queues 273 * @sk_lingertime: %SO_LINGER l_linger setting 274 * @sk_backlog: always used with the per-socket spinlock held 275 * @sk_callback_lock: used with the callbacks in the end of this struct 276 * @sk_error_queue: rarely used 277 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt, 278 * IPV6_ADDRFORM for instance) 279 * @sk_err: last error 280 * @sk_err_soft: errors that don't cause failure but are the cause of a 281 * persistent failure not just 'timed out' 282 * @sk_drops: raw/udp drops counter 283 * @sk_ack_backlog: current listen backlog 284 * @sk_max_ack_backlog: listen backlog set in listen() 285 * @sk_uid: user id of owner 286 * @sk_priority: %SO_PRIORITY setting 287 * @sk_type: socket type (%SOCK_STREAM, etc) 288 * @sk_protocol: which protocol this socket belongs in this network family 289 * @sk_peer_pid: &struct pid for this socket's peer 290 * @sk_peer_cred: %SO_PEERCRED setting 291 * @sk_rcvlowat: %SO_RCVLOWAT setting 292 * @sk_rcvtimeo: %SO_RCVTIMEO setting 293 * @sk_sndtimeo: %SO_SNDTIMEO setting 294 * @sk_txhash: computed flow hash for use on transmit 295 * @sk_filter: socket filtering instructions 296 * @sk_timer: sock cleanup timer 297 * @sk_stamp: time stamp of last packet received 298 * @sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only 299 * @sk_tsflags: SO_TIMESTAMPING socket options 300 * @sk_tskey: counter to disambiguate concurrent tstamp requests 301 * @sk_zckey: counter to order MSG_ZEROCOPY notifications 302 * @sk_socket: Identd and reporting IO signals 303 * @sk_user_data: RPC layer private data 304 * @sk_frag: cached page frag 305 * @sk_peek_off: current peek_offset value 306 * @sk_send_head: front of stuff to transmit 307 * @sk_security: used by security modules 308 * @sk_mark: generic packet mark 309 * @sk_cgrp_data: cgroup data for this cgroup 310 * @sk_memcg: this socket's memory cgroup association 311 * @sk_write_pending: a write to stream socket waits to start 312 * @sk_state_change: callback to indicate change in the state of the sock 313 * @sk_data_ready: callback to indicate there is data to be processed 314 * @sk_write_space: callback to indicate there is bf sending space available 315 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE) 316 * @sk_backlog_rcv: callback to process the backlog 317 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0 318 * @sk_reuseport_cb: reuseport group container 319 * @sk_rcu: used during RCU grace period 320 * @sk_clockid: clockid used by time-based scheduling (SO_TXTIME) 321 * @sk_txtime_deadline_mode: set deadline mode for SO_TXTIME 322 * @sk_txtime_unused: unused txtime flags 323 */ 324 struct sock { 325 /* 326 * Now struct inet_timewait_sock also uses sock_common, so please just 327 * don't add nothing before this first member (__sk_common) --acme 328 */ 329 struct sock_common __sk_common; 330 #define sk_node __sk_common.skc_node 331 #define sk_nulls_node __sk_common.skc_nulls_node 332 #define sk_refcnt __sk_common.skc_refcnt 333 #define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping 334 #ifdef CONFIG_XPS 335 #define sk_rx_queue_mapping __sk_common.skc_rx_queue_mapping 336 #endif 337 338 #define sk_dontcopy_begin __sk_common.skc_dontcopy_begin 339 #define sk_dontcopy_end __sk_common.skc_dontcopy_end 340 #define sk_hash __sk_common.skc_hash 341 #define sk_portpair __sk_common.skc_portpair 342 #define sk_num __sk_common.skc_num 343 #define sk_dport __sk_common.skc_dport 344 #define sk_addrpair __sk_common.skc_addrpair 345 #define sk_daddr __sk_common.skc_daddr 346 #define sk_rcv_saddr __sk_common.skc_rcv_saddr 347 #define sk_family __sk_common.skc_family 348 #define sk_state __sk_common.skc_state 349 #define sk_reuse __sk_common.skc_reuse 350 #define sk_reuseport __sk_common.skc_reuseport 351 #define sk_ipv6only __sk_common.skc_ipv6only 352 #define sk_net_refcnt __sk_common.skc_net_refcnt 353 #define sk_bound_dev_if __sk_common.skc_bound_dev_if 354 #define sk_bind_node __sk_common.skc_bind_node 355 #define sk_prot __sk_common.skc_prot 356 #define sk_net __sk_common.skc_net 357 #define sk_v6_daddr __sk_common.skc_v6_daddr 358 #define sk_v6_rcv_saddr __sk_common.skc_v6_rcv_saddr 359 #define sk_cookie __sk_common.skc_cookie 360 #define sk_incoming_cpu __sk_common.skc_incoming_cpu 361 #define sk_flags __sk_common.skc_flags 362 #define sk_rxhash __sk_common.skc_rxhash 363 364 socket_lock_t sk_lock; 365 atomic_t sk_drops; 366 int sk_rcvlowat; 367 struct sk_buff_head sk_error_queue; 368 struct sk_buff *sk_rx_skb_cache; 369 struct sk_buff_head sk_receive_queue; 370 /* 371 * The backlog queue is special, it is always used with 372 * the per-socket spinlock held and requires low latency 373 * access. Therefore we special case it's implementation. 374 * Note : rmem_alloc is in this structure to fill a hole 375 * on 64bit arches, not because its logically part of 376 * backlog. 377 */ 378 struct { 379 atomic_t rmem_alloc; 380 int len; 381 struct sk_buff *head; 382 struct sk_buff *tail; 383 } sk_backlog; 384 #define sk_rmem_alloc sk_backlog.rmem_alloc 385 386 int sk_forward_alloc; 387 #ifdef CONFIG_NET_RX_BUSY_POLL 388 unsigned int sk_ll_usec; 389 /* ===== mostly read cache line ===== */ 390 unsigned int sk_napi_id; 391 #endif 392 int sk_rcvbuf; 393 394 struct sk_filter __rcu *sk_filter; 395 union { 396 struct socket_wq __rcu *sk_wq; 397 struct socket_wq *sk_wq_raw; 398 }; 399 #ifdef CONFIG_XFRM 400 struct xfrm_policy __rcu *sk_policy[2]; 401 #endif 402 struct dst_entry *sk_rx_dst; 403 struct dst_entry __rcu *sk_dst_cache; 404 atomic_t sk_omem_alloc; 405 int sk_sndbuf; 406 407 /* ===== cache line for TX ===== */ 408 int sk_wmem_queued; 409 refcount_t sk_wmem_alloc; 410 unsigned long sk_tsq_flags; 411 union { 412 struct sk_buff *sk_send_head; 413 struct rb_root tcp_rtx_queue; 414 }; 415 struct sk_buff *sk_tx_skb_cache; 416 struct sk_buff_head sk_write_queue; 417 __s32 sk_peek_off; 418 int sk_write_pending; 419 __u32 sk_dst_pending_confirm; 420 u32 sk_pacing_status; /* see enum sk_pacing */ 421 long sk_sndtimeo; 422 struct timer_list sk_timer; 423 __u32 sk_priority; 424 __u32 sk_mark; 425 unsigned long sk_pacing_rate; /* bytes per second */ 426 unsigned long sk_max_pacing_rate; 427 struct page_frag sk_frag; 428 netdev_features_t sk_route_caps; 429 netdev_features_t sk_route_nocaps; 430 netdev_features_t sk_route_forced_caps; 431 int sk_gso_type; 432 unsigned int sk_gso_max_size; 433 gfp_t sk_allocation; 434 __u32 sk_txhash; 435 436 /* 437 * Because of non atomicity rules, all 438 * changes are protected by socket lock. 439 */ 440 unsigned int __sk_flags_offset[0]; 441 #ifdef __BIG_ENDIAN_BITFIELD 442 #define SK_FL_PROTO_SHIFT 16 443 #define SK_FL_PROTO_MASK 0x00ff0000 444 445 #define SK_FL_TYPE_SHIFT 0 446 #define SK_FL_TYPE_MASK 0x0000ffff 447 #else 448 #define SK_FL_PROTO_SHIFT 8 449 #define SK_FL_PROTO_MASK 0x0000ff00 450 451 #define SK_FL_TYPE_SHIFT 16 452 #define SK_FL_TYPE_MASK 0xffff0000 453 #endif 454 455 unsigned int sk_padding : 1, 456 sk_kern_sock : 1, 457 sk_no_check_tx : 1, 458 sk_no_check_rx : 1, 459 sk_userlocks : 4, 460 sk_protocol : 8, 461 sk_type : 16; 462 #define SK_PROTOCOL_MAX U8_MAX 463 u16 sk_gso_max_segs; 464 u8 sk_pacing_shift; 465 unsigned long sk_lingertime; 466 struct proto *sk_prot_creator; 467 rwlock_t sk_callback_lock; 468 int sk_err, 469 sk_err_soft; 470 u32 sk_ack_backlog; 471 u32 sk_max_ack_backlog; 472 kuid_t sk_uid; 473 struct pid *sk_peer_pid; 474 const struct cred *sk_peer_cred; 475 long sk_rcvtimeo; 476 ktime_t sk_stamp; 477 #if BITS_PER_LONG==32 478 seqlock_t sk_stamp_seq; 479 #endif 480 u16 sk_tsflags; 481 u8 sk_shutdown; 482 u32 sk_tskey; 483 atomic_t sk_zckey; 484 485 u8 sk_clockid; 486 u8 sk_txtime_deadline_mode : 1, 487 sk_txtime_report_errors : 1, 488 sk_txtime_unused : 6; 489 490 struct socket *sk_socket; 491 void *sk_user_data; 492 #ifdef CONFIG_SECURITY 493 void *sk_security; 494 #endif 495 struct sock_cgroup_data sk_cgrp_data; 496 struct mem_cgroup *sk_memcg; 497 void (*sk_state_change)(struct sock *sk); 498 void (*sk_data_ready)(struct sock *sk); 499 void (*sk_write_space)(struct sock *sk); 500 void (*sk_error_report)(struct sock *sk); 501 int (*sk_backlog_rcv)(struct sock *sk, 502 struct sk_buff *skb); 503 #ifdef CONFIG_SOCK_VALIDATE_XMIT 504 struct sk_buff* (*sk_validate_xmit_skb)(struct sock *sk, 505 struct net_device *dev, 506 struct sk_buff *skb); 507 #endif 508 void (*sk_destruct)(struct sock *sk); 509 struct sock_reuseport __rcu *sk_reuseport_cb; 510 #ifdef CONFIG_BPF_SYSCALL 511 struct bpf_sk_storage __rcu *sk_bpf_storage; 512 #endif 513 struct rcu_head sk_rcu; 514 }; 515 516 enum sk_pacing { 517 SK_PACING_NONE = 0, 518 SK_PACING_NEEDED = 1, 519 SK_PACING_FQ = 2, 520 }; 521 522 #define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data))) 523 524 #define rcu_dereference_sk_user_data(sk) rcu_dereference(__sk_user_data((sk))) 525 #define rcu_assign_sk_user_data(sk, ptr) rcu_assign_pointer(__sk_user_data((sk)), ptr) 526 527 /* 528 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK 529 * or not whether his port will be reused by someone else. SK_FORCE_REUSE 530 * on a socket means that the socket will reuse everybody else's port 531 * without looking at the other's sk_reuse value. 532 */ 533 534 #define SK_NO_REUSE 0 535 #define SK_CAN_REUSE 1 536 #define SK_FORCE_REUSE 2 537 538 int sk_set_peek_off(struct sock *sk, int val); 539 540 static inline int sk_peek_offset(struct sock *sk, int flags) 541 { 542 if (unlikely(flags & MSG_PEEK)) { 543 return READ_ONCE(sk->sk_peek_off); 544 } 545 546 return 0; 547 } 548 549 static inline void sk_peek_offset_bwd(struct sock *sk, int val) 550 { 551 s32 off = READ_ONCE(sk->sk_peek_off); 552 553 if (unlikely(off >= 0)) { 554 off = max_t(s32, off - val, 0); 555 WRITE_ONCE(sk->sk_peek_off, off); 556 } 557 } 558 559 static inline void sk_peek_offset_fwd(struct sock *sk, int val) 560 { 561 sk_peek_offset_bwd(sk, -val); 562 } 563 564 /* 565 * Hashed lists helper routines 566 */ 567 static inline struct sock *sk_entry(const struct hlist_node *node) 568 { 569 return hlist_entry(node, struct sock, sk_node); 570 } 571 572 static inline struct sock *__sk_head(const struct hlist_head *head) 573 { 574 return hlist_entry(head->first, struct sock, sk_node); 575 } 576 577 static inline struct sock *sk_head(const struct hlist_head *head) 578 { 579 return hlist_empty(head) ? NULL : __sk_head(head); 580 } 581 582 static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head) 583 { 584 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node); 585 } 586 587 static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head) 588 { 589 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head); 590 } 591 592 static inline struct sock *sk_next(const struct sock *sk) 593 { 594 return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node); 595 } 596 597 static inline struct sock *sk_nulls_next(const struct sock *sk) 598 { 599 return (!is_a_nulls(sk->sk_nulls_node.next)) ? 600 hlist_nulls_entry(sk->sk_nulls_node.next, 601 struct sock, sk_nulls_node) : 602 NULL; 603 } 604 605 static inline bool sk_unhashed(const struct sock *sk) 606 { 607 return hlist_unhashed(&sk->sk_node); 608 } 609 610 static inline bool sk_hashed(const struct sock *sk) 611 { 612 return !sk_unhashed(sk); 613 } 614 615 static inline void sk_node_init(struct hlist_node *node) 616 { 617 node->pprev = NULL; 618 } 619 620 static inline void sk_nulls_node_init(struct hlist_nulls_node *node) 621 { 622 node->pprev = NULL; 623 } 624 625 static inline void __sk_del_node(struct sock *sk) 626 { 627 __hlist_del(&sk->sk_node); 628 } 629 630 /* NB: equivalent to hlist_del_init_rcu */ 631 static inline bool __sk_del_node_init(struct sock *sk) 632 { 633 if (sk_hashed(sk)) { 634 __sk_del_node(sk); 635 sk_node_init(&sk->sk_node); 636 return true; 637 } 638 return false; 639 } 640 641 /* Grab socket reference count. This operation is valid only 642 when sk is ALREADY grabbed f.e. it is found in hash table 643 or a list and the lookup is made under lock preventing hash table 644 modifications. 645 */ 646 647 static __always_inline void sock_hold(struct sock *sk) 648 { 649 refcount_inc(&sk->sk_refcnt); 650 } 651 652 /* Ungrab socket in the context, which assumes that socket refcnt 653 cannot hit zero, f.e. it is true in context of any socketcall. 654 */ 655 static __always_inline void __sock_put(struct sock *sk) 656 { 657 refcount_dec(&sk->sk_refcnt); 658 } 659 660 static inline bool sk_del_node_init(struct sock *sk) 661 { 662 bool rc = __sk_del_node_init(sk); 663 664 if (rc) { 665 /* paranoid for a while -acme */ 666 WARN_ON(refcount_read(&sk->sk_refcnt) == 1); 667 __sock_put(sk); 668 } 669 return rc; 670 } 671 #define sk_del_node_init_rcu(sk) sk_del_node_init(sk) 672 673 static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk) 674 { 675 if (sk_hashed(sk)) { 676 hlist_nulls_del_init_rcu(&sk->sk_nulls_node); 677 return true; 678 } 679 return false; 680 } 681 682 static inline bool sk_nulls_del_node_init_rcu(struct sock *sk) 683 { 684 bool rc = __sk_nulls_del_node_init_rcu(sk); 685 686 if (rc) { 687 /* paranoid for a while -acme */ 688 WARN_ON(refcount_read(&sk->sk_refcnt) == 1); 689 __sock_put(sk); 690 } 691 return rc; 692 } 693 694 static inline void __sk_add_node(struct sock *sk, struct hlist_head *list) 695 { 696 hlist_add_head(&sk->sk_node, list); 697 } 698 699 static inline void sk_add_node(struct sock *sk, struct hlist_head *list) 700 { 701 sock_hold(sk); 702 __sk_add_node(sk, list); 703 } 704 705 static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list) 706 { 707 sock_hold(sk); 708 if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport && 709 sk->sk_family == AF_INET6) 710 hlist_add_tail_rcu(&sk->sk_node, list); 711 else 712 hlist_add_head_rcu(&sk->sk_node, list); 713 } 714 715 static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list) 716 { 717 sock_hold(sk); 718 hlist_add_tail_rcu(&sk->sk_node, list); 719 } 720 721 static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list) 722 { 723 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list); 724 } 725 726 static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list) 727 { 728 sock_hold(sk); 729 __sk_nulls_add_node_rcu(sk, list); 730 } 731 732 static inline void __sk_del_bind_node(struct sock *sk) 733 { 734 __hlist_del(&sk->sk_bind_node); 735 } 736 737 static inline void sk_add_bind_node(struct sock *sk, 738 struct hlist_head *list) 739 { 740 hlist_add_head(&sk->sk_bind_node, list); 741 } 742 743 #define sk_for_each(__sk, list) \ 744 hlist_for_each_entry(__sk, list, sk_node) 745 #define sk_for_each_rcu(__sk, list) \ 746 hlist_for_each_entry_rcu(__sk, list, sk_node) 747 #define sk_nulls_for_each(__sk, node, list) \ 748 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node) 749 #define sk_nulls_for_each_rcu(__sk, node, list) \ 750 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node) 751 #define sk_for_each_from(__sk) \ 752 hlist_for_each_entry_from(__sk, sk_node) 753 #define sk_nulls_for_each_from(__sk, node) \ 754 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \ 755 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node) 756 #define sk_for_each_safe(__sk, tmp, list) \ 757 hlist_for_each_entry_safe(__sk, tmp, list, sk_node) 758 #define sk_for_each_bound(__sk, list) \ 759 hlist_for_each_entry(__sk, list, sk_bind_node) 760 761 /** 762 * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset 763 * @tpos: the type * to use as a loop cursor. 764 * @pos: the &struct hlist_node to use as a loop cursor. 765 * @head: the head for your list. 766 * @offset: offset of hlist_node within the struct. 767 * 768 */ 769 #define sk_for_each_entry_offset_rcu(tpos, pos, head, offset) \ 770 for (pos = rcu_dereference(hlist_first_rcu(head)); \ 771 pos != NULL && \ 772 ({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \ 773 pos = rcu_dereference(hlist_next_rcu(pos))) 774 775 static inline struct user_namespace *sk_user_ns(struct sock *sk) 776 { 777 /* Careful only use this in a context where these parameters 778 * can not change and must all be valid, such as recvmsg from 779 * userspace. 780 */ 781 return sk->sk_socket->file->f_cred->user_ns; 782 } 783 784 /* Sock flags */ 785 enum sock_flags { 786 SOCK_DEAD, 787 SOCK_DONE, 788 SOCK_URGINLINE, 789 SOCK_KEEPOPEN, 790 SOCK_LINGER, 791 SOCK_DESTROY, 792 SOCK_BROADCAST, 793 SOCK_TIMESTAMP, 794 SOCK_ZAPPED, 795 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */ 796 SOCK_DBG, /* %SO_DEBUG setting */ 797 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */ 798 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */ 799 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */ 800 SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */ 801 SOCK_MEMALLOC, /* VM depends on this socket for swapping */ 802 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */ 803 SOCK_FASYNC, /* fasync() active */ 804 SOCK_RXQ_OVFL, 805 SOCK_ZEROCOPY, /* buffers from userspace */ 806 SOCK_WIFI_STATUS, /* push wifi status to userspace */ 807 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS. 808 * Will use last 4 bytes of packet sent from 809 * user-space instead. 810 */ 811 SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */ 812 SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */ 813 SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */ 814 SOCK_TXTIME, 815 SOCK_XDP, /* XDP is attached */ 816 SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */ 817 }; 818 819 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)) 820 821 static inline void sock_copy_flags(struct sock *nsk, struct sock *osk) 822 { 823 nsk->sk_flags = osk->sk_flags; 824 } 825 826 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag) 827 { 828 __set_bit(flag, &sk->sk_flags); 829 } 830 831 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag) 832 { 833 __clear_bit(flag, &sk->sk_flags); 834 } 835 836 static inline bool sock_flag(const struct sock *sk, enum sock_flags flag) 837 { 838 return test_bit(flag, &sk->sk_flags); 839 } 840 841 #ifdef CONFIG_NET 842 DECLARE_STATIC_KEY_FALSE(memalloc_socks_key); 843 static inline int sk_memalloc_socks(void) 844 { 845 return static_branch_unlikely(&memalloc_socks_key); 846 } 847 #else 848 849 static inline int sk_memalloc_socks(void) 850 { 851 return 0; 852 } 853 854 #endif 855 856 static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask) 857 { 858 return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC); 859 } 860 861 static inline void sk_acceptq_removed(struct sock *sk) 862 { 863 sk->sk_ack_backlog--; 864 } 865 866 static inline void sk_acceptq_added(struct sock *sk) 867 { 868 sk->sk_ack_backlog++; 869 } 870 871 static inline bool sk_acceptq_is_full(const struct sock *sk) 872 { 873 return sk->sk_ack_backlog > sk->sk_max_ack_backlog; 874 } 875 876 /* 877 * Compute minimal free write space needed to queue new packets. 878 */ 879 static inline int sk_stream_min_wspace(const struct sock *sk) 880 { 881 return READ_ONCE(sk->sk_wmem_queued) >> 1; 882 } 883 884 static inline int sk_stream_wspace(const struct sock *sk) 885 { 886 return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued); 887 } 888 889 static inline void sk_wmem_queued_add(struct sock *sk, int val) 890 { 891 WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val); 892 } 893 894 void sk_stream_write_space(struct sock *sk); 895 896 /* OOB backlog add */ 897 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb) 898 { 899 /* dont let skb dst not refcounted, we are going to leave rcu lock */ 900 skb_dst_force(skb); 901 902 if (!sk->sk_backlog.tail) 903 sk->sk_backlog.head = skb; 904 else 905 sk->sk_backlog.tail->next = skb; 906 907 sk->sk_backlog.tail = skb; 908 skb->next = NULL; 909 } 910 911 /* 912 * Take into account size of receive queue and backlog queue 913 * Do not take into account this skb truesize, 914 * to allow even a single big packet to come. 915 */ 916 static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit) 917 { 918 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc); 919 920 return qsize > limit; 921 } 922 923 /* The per-socket spinlock must be held here. */ 924 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb, 925 unsigned int limit) 926 { 927 if (sk_rcvqueues_full(sk, limit)) 928 return -ENOBUFS; 929 930 /* 931 * If the skb was allocated from pfmemalloc reserves, only 932 * allow SOCK_MEMALLOC sockets to use it as this socket is 933 * helping free memory 934 */ 935 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) 936 return -ENOMEM; 937 938 __sk_add_backlog(sk, skb); 939 sk->sk_backlog.len += skb->truesize; 940 return 0; 941 } 942 943 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb); 944 945 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 946 { 947 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) 948 return __sk_backlog_rcv(sk, skb); 949 950 return sk->sk_backlog_rcv(sk, skb); 951 } 952 953 static inline void sk_incoming_cpu_update(struct sock *sk) 954 { 955 int cpu = raw_smp_processor_id(); 956 957 if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu)) 958 WRITE_ONCE(sk->sk_incoming_cpu, cpu); 959 } 960 961 static inline void sock_rps_record_flow_hash(__u32 hash) 962 { 963 #ifdef CONFIG_RPS 964 struct rps_sock_flow_table *sock_flow_table; 965 966 rcu_read_lock(); 967 sock_flow_table = rcu_dereference(rps_sock_flow_table); 968 rps_record_sock_flow(sock_flow_table, hash); 969 rcu_read_unlock(); 970 #endif 971 } 972 973 static inline void sock_rps_record_flow(const struct sock *sk) 974 { 975 #ifdef CONFIG_RPS 976 if (static_branch_unlikely(&rfs_needed)) { 977 /* Reading sk->sk_rxhash might incur an expensive cache line 978 * miss. 979 * 980 * TCP_ESTABLISHED does cover almost all states where RFS 981 * might be useful, and is cheaper [1] than testing : 982 * IPv4: inet_sk(sk)->inet_daddr 983 * IPv6: ipv6_addr_any(&sk->sk_v6_daddr) 984 * OR an additional socket flag 985 * [1] : sk_state and sk_prot are in the same cache line. 986 */ 987 if (sk->sk_state == TCP_ESTABLISHED) 988 sock_rps_record_flow_hash(sk->sk_rxhash); 989 } 990 #endif 991 } 992 993 static inline void sock_rps_save_rxhash(struct sock *sk, 994 const struct sk_buff *skb) 995 { 996 #ifdef CONFIG_RPS 997 if (unlikely(sk->sk_rxhash != skb->hash)) 998 sk->sk_rxhash = skb->hash; 999 #endif 1000 } 1001 1002 static inline void sock_rps_reset_rxhash(struct sock *sk) 1003 { 1004 #ifdef CONFIG_RPS 1005 sk->sk_rxhash = 0; 1006 #endif 1007 } 1008 1009 #define sk_wait_event(__sk, __timeo, __condition, __wait) \ 1010 ({ int __rc; \ 1011 release_sock(__sk); \ 1012 __rc = __condition; \ 1013 if (!__rc) { \ 1014 *(__timeo) = wait_woken(__wait, \ 1015 TASK_INTERRUPTIBLE, \ 1016 *(__timeo)); \ 1017 } \ 1018 sched_annotate_sleep(); \ 1019 lock_sock(__sk); \ 1020 __rc = __condition; \ 1021 __rc; \ 1022 }) 1023 1024 int sk_stream_wait_connect(struct sock *sk, long *timeo_p); 1025 int sk_stream_wait_memory(struct sock *sk, long *timeo_p); 1026 void sk_stream_wait_close(struct sock *sk, long timeo_p); 1027 int sk_stream_error(struct sock *sk, int flags, int err); 1028 void sk_stream_kill_queues(struct sock *sk); 1029 void sk_set_memalloc(struct sock *sk); 1030 void sk_clear_memalloc(struct sock *sk); 1031 1032 void __sk_flush_backlog(struct sock *sk); 1033 1034 static inline bool sk_flush_backlog(struct sock *sk) 1035 { 1036 if (unlikely(READ_ONCE(sk->sk_backlog.tail))) { 1037 __sk_flush_backlog(sk); 1038 return true; 1039 } 1040 return false; 1041 } 1042 1043 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb); 1044 1045 struct request_sock_ops; 1046 struct timewait_sock_ops; 1047 struct inet_hashinfo; 1048 struct raw_hashinfo; 1049 struct smc_hashinfo; 1050 struct module; 1051 1052 /* 1053 * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes 1054 * un-modified. Special care is taken when initializing object to zero. 1055 */ 1056 static inline void sk_prot_clear_nulls(struct sock *sk, int size) 1057 { 1058 if (offsetof(struct sock, sk_node.next) != 0) 1059 memset(sk, 0, offsetof(struct sock, sk_node.next)); 1060 memset(&sk->sk_node.pprev, 0, 1061 size - offsetof(struct sock, sk_node.pprev)); 1062 } 1063 1064 /* Networking protocol blocks we attach to sockets. 1065 * socket layer -> transport layer interface 1066 */ 1067 struct proto { 1068 void (*close)(struct sock *sk, 1069 long timeout); 1070 int (*pre_connect)(struct sock *sk, 1071 struct sockaddr *uaddr, 1072 int addr_len); 1073 int (*connect)(struct sock *sk, 1074 struct sockaddr *uaddr, 1075 int addr_len); 1076 int (*disconnect)(struct sock *sk, int flags); 1077 1078 struct sock * (*accept)(struct sock *sk, int flags, int *err, 1079 bool kern); 1080 1081 int (*ioctl)(struct sock *sk, int cmd, 1082 unsigned long arg); 1083 int (*init)(struct sock *sk); 1084 void (*destroy)(struct sock *sk); 1085 void (*shutdown)(struct sock *sk, int how); 1086 int (*setsockopt)(struct sock *sk, int level, 1087 int optname, char __user *optval, 1088 unsigned int optlen); 1089 int (*getsockopt)(struct sock *sk, int level, 1090 int optname, char __user *optval, 1091 int __user *option); 1092 void (*keepalive)(struct sock *sk, int valbool); 1093 #ifdef CONFIG_COMPAT 1094 int (*compat_setsockopt)(struct sock *sk, 1095 int level, 1096 int optname, char __user *optval, 1097 unsigned int optlen); 1098 int (*compat_getsockopt)(struct sock *sk, 1099 int level, 1100 int optname, char __user *optval, 1101 int __user *option); 1102 int (*compat_ioctl)(struct sock *sk, 1103 unsigned int cmd, unsigned long arg); 1104 #endif 1105 int (*sendmsg)(struct sock *sk, struct msghdr *msg, 1106 size_t len); 1107 int (*recvmsg)(struct sock *sk, struct msghdr *msg, 1108 size_t len, int noblock, int flags, 1109 int *addr_len); 1110 int (*sendpage)(struct sock *sk, struct page *page, 1111 int offset, size_t size, int flags); 1112 int (*bind)(struct sock *sk, 1113 struct sockaddr *uaddr, int addr_len); 1114 1115 int (*backlog_rcv) (struct sock *sk, 1116 struct sk_buff *skb); 1117 1118 void (*release_cb)(struct sock *sk); 1119 1120 /* Keeping track of sk's, looking them up, and port selection methods. */ 1121 int (*hash)(struct sock *sk); 1122 void (*unhash)(struct sock *sk); 1123 void (*rehash)(struct sock *sk); 1124 int (*get_port)(struct sock *sk, unsigned short snum); 1125 1126 /* Keeping track of sockets in use */ 1127 #ifdef CONFIG_PROC_FS 1128 unsigned int inuse_idx; 1129 #endif 1130 1131 bool (*stream_memory_free)(const struct sock *sk, int wake); 1132 bool (*stream_memory_read)(const struct sock *sk); 1133 /* Memory pressure */ 1134 void (*enter_memory_pressure)(struct sock *sk); 1135 void (*leave_memory_pressure)(struct sock *sk); 1136 atomic_long_t *memory_allocated; /* Current allocated memory. */ 1137 struct percpu_counter *sockets_allocated; /* Current number of sockets. */ 1138 /* 1139 * Pressure flag: try to collapse. 1140 * Technical note: it is used by multiple contexts non atomically. 1141 * All the __sk_mem_schedule() is of this nature: accounting 1142 * is strict, actions are advisory and have some latency. 1143 */ 1144 unsigned long *memory_pressure; 1145 long *sysctl_mem; 1146 1147 int *sysctl_wmem; 1148 int *sysctl_rmem; 1149 u32 sysctl_wmem_offset; 1150 u32 sysctl_rmem_offset; 1151 1152 int max_header; 1153 bool no_autobind; 1154 1155 struct kmem_cache *slab; 1156 unsigned int obj_size; 1157 slab_flags_t slab_flags; 1158 unsigned int useroffset; /* Usercopy region offset */ 1159 unsigned int usersize; /* Usercopy region size */ 1160 1161 struct percpu_counter *orphan_count; 1162 1163 struct request_sock_ops *rsk_prot; 1164 struct timewait_sock_ops *twsk_prot; 1165 1166 union { 1167 struct inet_hashinfo *hashinfo; 1168 struct udp_table *udp_table; 1169 struct raw_hashinfo *raw_hash; 1170 struct smc_hashinfo *smc_hash; 1171 } h; 1172 1173 struct module *owner; 1174 1175 char name[32]; 1176 1177 struct list_head node; 1178 #ifdef SOCK_REFCNT_DEBUG 1179 atomic_t socks; 1180 #endif 1181 int (*diag_destroy)(struct sock *sk, int err); 1182 } __randomize_layout; 1183 1184 int proto_register(struct proto *prot, int alloc_slab); 1185 void proto_unregister(struct proto *prot); 1186 int sock_load_diag_module(int family, int protocol); 1187 1188 #ifdef SOCK_REFCNT_DEBUG 1189 static inline void sk_refcnt_debug_inc(struct sock *sk) 1190 { 1191 atomic_inc(&sk->sk_prot->socks); 1192 } 1193 1194 static inline void sk_refcnt_debug_dec(struct sock *sk) 1195 { 1196 atomic_dec(&sk->sk_prot->socks); 1197 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n", 1198 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks)); 1199 } 1200 1201 static inline void sk_refcnt_debug_release(const struct sock *sk) 1202 { 1203 if (refcount_read(&sk->sk_refcnt) != 1) 1204 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n", 1205 sk->sk_prot->name, sk, refcount_read(&sk->sk_refcnt)); 1206 } 1207 #else /* SOCK_REFCNT_DEBUG */ 1208 #define sk_refcnt_debug_inc(sk) do { } while (0) 1209 #define sk_refcnt_debug_dec(sk) do { } while (0) 1210 #define sk_refcnt_debug_release(sk) do { } while (0) 1211 #endif /* SOCK_REFCNT_DEBUG */ 1212 1213 static inline bool __sk_stream_memory_free(const struct sock *sk, int wake) 1214 { 1215 if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf)) 1216 return false; 1217 1218 return sk->sk_prot->stream_memory_free ? 1219 sk->sk_prot->stream_memory_free(sk, wake) : true; 1220 } 1221 1222 static inline bool sk_stream_memory_free(const struct sock *sk) 1223 { 1224 return __sk_stream_memory_free(sk, 0); 1225 } 1226 1227 static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake) 1228 { 1229 return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) && 1230 __sk_stream_memory_free(sk, wake); 1231 } 1232 1233 static inline bool sk_stream_is_writeable(const struct sock *sk) 1234 { 1235 return __sk_stream_is_writeable(sk, 0); 1236 } 1237 1238 static inline int sk_under_cgroup_hierarchy(struct sock *sk, 1239 struct cgroup *ancestor) 1240 { 1241 #ifdef CONFIG_SOCK_CGROUP_DATA 1242 return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data), 1243 ancestor); 1244 #else 1245 return -ENOTSUPP; 1246 #endif 1247 } 1248 1249 static inline bool sk_has_memory_pressure(const struct sock *sk) 1250 { 1251 return sk->sk_prot->memory_pressure != NULL; 1252 } 1253 1254 static inline bool sk_under_memory_pressure(const struct sock *sk) 1255 { 1256 if (!sk->sk_prot->memory_pressure) 1257 return false; 1258 1259 if (mem_cgroup_sockets_enabled && sk->sk_memcg && 1260 mem_cgroup_under_socket_pressure(sk->sk_memcg)) 1261 return true; 1262 1263 return !!*sk->sk_prot->memory_pressure; 1264 } 1265 1266 static inline long 1267 sk_memory_allocated(const struct sock *sk) 1268 { 1269 return atomic_long_read(sk->sk_prot->memory_allocated); 1270 } 1271 1272 static inline long 1273 sk_memory_allocated_add(struct sock *sk, int amt) 1274 { 1275 return atomic_long_add_return(amt, sk->sk_prot->memory_allocated); 1276 } 1277 1278 static inline void 1279 sk_memory_allocated_sub(struct sock *sk, int amt) 1280 { 1281 atomic_long_sub(amt, sk->sk_prot->memory_allocated); 1282 } 1283 1284 static inline void sk_sockets_allocated_dec(struct sock *sk) 1285 { 1286 percpu_counter_dec(sk->sk_prot->sockets_allocated); 1287 } 1288 1289 static inline void sk_sockets_allocated_inc(struct sock *sk) 1290 { 1291 percpu_counter_inc(sk->sk_prot->sockets_allocated); 1292 } 1293 1294 static inline u64 1295 sk_sockets_allocated_read_positive(struct sock *sk) 1296 { 1297 return percpu_counter_read_positive(sk->sk_prot->sockets_allocated); 1298 } 1299 1300 static inline int 1301 proto_sockets_allocated_sum_positive(struct proto *prot) 1302 { 1303 return percpu_counter_sum_positive(prot->sockets_allocated); 1304 } 1305 1306 static inline long 1307 proto_memory_allocated(struct proto *prot) 1308 { 1309 return atomic_long_read(prot->memory_allocated); 1310 } 1311 1312 static inline bool 1313 proto_memory_pressure(struct proto *prot) 1314 { 1315 if (!prot->memory_pressure) 1316 return false; 1317 return !!*prot->memory_pressure; 1318 } 1319 1320 1321 #ifdef CONFIG_PROC_FS 1322 /* Called with local bh disabled */ 1323 void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc); 1324 int sock_prot_inuse_get(struct net *net, struct proto *proto); 1325 int sock_inuse_get(struct net *net); 1326 #else 1327 static inline void sock_prot_inuse_add(struct net *net, struct proto *prot, 1328 int inc) 1329 { 1330 } 1331 #endif 1332 1333 1334 /* With per-bucket locks this operation is not-atomic, so that 1335 * this version is not worse. 1336 */ 1337 static inline int __sk_prot_rehash(struct sock *sk) 1338 { 1339 sk->sk_prot->unhash(sk); 1340 return sk->sk_prot->hash(sk); 1341 } 1342 1343 /* About 10 seconds */ 1344 #define SOCK_DESTROY_TIME (10*HZ) 1345 1346 /* Sockets 0-1023 can't be bound to unless you are superuser */ 1347 #define PROT_SOCK 1024 1348 1349 #define SHUTDOWN_MASK 3 1350 #define RCV_SHUTDOWN 1 1351 #define SEND_SHUTDOWN 2 1352 1353 #define SOCK_SNDBUF_LOCK 1 1354 #define SOCK_RCVBUF_LOCK 2 1355 #define SOCK_BINDADDR_LOCK 4 1356 #define SOCK_BINDPORT_LOCK 8 1357 1358 struct socket_alloc { 1359 struct socket socket; 1360 struct inode vfs_inode; 1361 }; 1362 1363 static inline struct socket *SOCKET_I(struct inode *inode) 1364 { 1365 return &container_of(inode, struct socket_alloc, vfs_inode)->socket; 1366 } 1367 1368 static inline struct inode *SOCK_INODE(struct socket *socket) 1369 { 1370 return &container_of(socket, struct socket_alloc, socket)->vfs_inode; 1371 } 1372 1373 /* 1374 * Functions for memory accounting 1375 */ 1376 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind); 1377 int __sk_mem_schedule(struct sock *sk, int size, int kind); 1378 void __sk_mem_reduce_allocated(struct sock *sk, int amount); 1379 void __sk_mem_reclaim(struct sock *sk, int amount); 1380 1381 /* We used to have PAGE_SIZE here, but systems with 64KB pages 1382 * do not necessarily have 16x time more memory than 4KB ones. 1383 */ 1384 #define SK_MEM_QUANTUM 4096 1385 #define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM) 1386 #define SK_MEM_SEND 0 1387 #define SK_MEM_RECV 1 1388 1389 /* sysctl_mem values are in pages, we convert them in SK_MEM_QUANTUM units */ 1390 static inline long sk_prot_mem_limits(const struct sock *sk, int index) 1391 { 1392 long val = sk->sk_prot->sysctl_mem[index]; 1393 1394 #if PAGE_SIZE > SK_MEM_QUANTUM 1395 val <<= PAGE_SHIFT - SK_MEM_QUANTUM_SHIFT; 1396 #elif PAGE_SIZE < SK_MEM_QUANTUM 1397 val >>= SK_MEM_QUANTUM_SHIFT - PAGE_SHIFT; 1398 #endif 1399 return val; 1400 } 1401 1402 static inline int sk_mem_pages(int amt) 1403 { 1404 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT; 1405 } 1406 1407 static inline bool sk_has_account(struct sock *sk) 1408 { 1409 /* return true if protocol supports memory accounting */ 1410 return !!sk->sk_prot->memory_allocated; 1411 } 1412 1413 static inline bool sk_wmem_schedule(struct sock *sk, int size) 1414 { 1415 if (!sk_has_account(sk)) 1416 return true; 1417 return size <= sk->sk_forward_alloc || 1418 __sk_mem_schedule(sk, size, SK_MEM_SEND); 1419 } 1420 1421 static inline bool 1422 sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size) 1423 { 1424 if (!sk_has_account(sk)) 1425 return true; 1426 return size<= sk->sk_forward_alloc || 1427 __sk_mem_schedule(sk, size, SK_MEM_RECV) || 1428 skb_pfmemalloc(skb); 1429 } 1430 1431 static inline void sk_mem_reclaim(struct sock *sk) 1432 { 1433 if (!sk_has_account(sk)) 1434 return; 1435 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM) 1436 __sk_mem_reclaim(sk, sk->sk_forward_alloc); 1437 } 1438 1439 static inline void sk_mem_reclaim_partial(struct sock *sk) 1440 { 1441 if (!sk_has_account(sk)) 1442 return; 1443 if (sk->sk_forward_alloc > SK_MEM_QUANTUM) 1444 __sk_mem_reclaim(sk, sk->sk_forward_alloc - 1); 1445 } 1446 1447 static inline void sk_mem_charge(struct sock *sk, int size) 1448 { 1449 if (!sk_has_account(sk)) 1450 return; 1451 sk->sk_forward_alloc -= size; 1452 } 1453 1454 static inline void sk_mem_uncharge(struct sock *sk, int size) 1455 { 1456 if (!sk_has_account(sk)) 1457 return; 1458 sk->sk_forward_alloc += size; 1459 1460 /* Avoid a possible overflow. 1461 * TCP send queues can make this happen, if sk_mem_reclaim() 1462 * is not called and more than 2 GBytes are released at once. 1463 * 1464 * If we reach 2 MBytes, reclaim 1 MBytes right now, there is 1465 * no need to hold that much forward allocation anyway. 1466 */ 1467 if (unlikely(sk->sk_forward_alloc >= 1 << 21)) 1468 __sk_mem_reclaim(sk, 1 << 20); 1469 } 1470 1471 DECLARE_STATIC_KEY_FALSE(tcp_tx_skb_cache_key); 1472 static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb) 1473 { 1474 sock_set_flag(sk, SOCK_QUEUE_SHRUNK); 1475 sk_wmem_queued_add(sk, -skb->truesize); 1476 sk_mem_uncharge(sk, skb->truesize); 1477 if (static_branch_unlikely(&tcp_tx_skb_cache_key) && 1478 !sk->sk_tx_skb_cache && !skb_cloned(skb)) { 1479 skb_zcopy_clear(skb, true); 1480 sk->sk_tx_skb_cache = skb; 1481 return; 1482 } 1483 __kfree_skb(skb); 1484 } 1485 1486 static inline void sock_release_ownership(struct sock *sk) 1487 { 1488 if (sk->sk_lock.owned) { 1489 sk->sk_lock.owned = 0; 1490 1491 /* The sk_lock has mutex_unlock() semantics: */ 1492 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); 1493 } 1494 } 1495 1496 /* 1497 * Macro so as to not evaluate some arguments when 1498 * lockdep is not enabled. 1499 * 1500 * Mark both the sk_lock and the sk_lock.slock as a 1501 * per-address-family lock class. 1502 */ 1503 #define sock_lock_init_class_and_name(sk, sname, skey, name, key) \ 1504 do { \ 1505 sk->sk_lock.owned = 0; \ 1506 init_waitqueue_head(&sk->sk_lock.wq); \ 1507 spin_lock_init(&(sk)->sk_lock.slock); \ 1508 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \ 1509 sizeof((sk)->sk_lock)); \ 1510 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \ 1511 (skey), (sname)); \ 1512 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \ 1513 } while (0) 1514 1515 #ifdef CONFIG_LOCKDEP 1516 static inline bool lockdep_sock_is_held(const struct sock *sk) 1517 { 1518 return lockdep_is_held(&sk->sk_lock) || 1519 lockdep_is_held(&sk->sk_lock.slock); 1520 } 1521 #endif 1522 1523 void lock_sock_nested(struct sock *sk, int subclass); 1524 1525 static inline void lock_sock(struct sock *sk) 1526 { 1527 lock_sock_nested(sk, 0); 1528 } 1529 1530 void __release_sock(struct sock *sk); 1531 void release_sock(struct sock *sk); 1532 1533 /* BH context may only use the following locking interface. */ 1534 #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock)) 1535 #define bh_lock_sock_nested(__sk) \ 1536 spin_lock_nested(&((__sk)->sk_lock.slock), \ 1537 SINGLE_DEPTH_NESTING) 1538 #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock)) 1539 1540 bool lock_sock_fast(struct sock *sk); 1541 /** 1542 * unlock_sock_fast - complement of lock_sock_fast 1543 * @sk: socket 1544 * @slow: slow mode 1545 * 1546 * fast unlock socket for user context. 1547 * If slow mode is on, we call regular release_sock() 1548 */ 1549 static inline void unlock_sock_fast(struct sock *sk, bool slow) 1550 { 1551 if (slow) 1552 release_sock(sk); 1553 else 1554 spin_unlock_bh(&sk->sk_lock.slock); 1555 } 1556 1557 /* Used by processes to "lock" a socket state, so that 1558 * interrupts and bottom half handlers won't change it 1559 * from under us. It essentially blocks any incoming 1560 * packets, so that we won't get any new data or any 1561 * packets that change the state of the socket. 1562 * 1563 * While locked, BH processing will add new packets to 1564 * the backlog queue. This queue is processed by the 1565 * owner of the socket lock right before it is released. 1566 * 1567 * Since ~2.3.5 it is also exclusive sleep lock serializing 1568 * accesses from user process context. 1569 */ 1570 1571 static inline void sock_owned_by_me(const struct sock *sk) 1572 { 1573 #ifdef CONFIG_LOCKDEP 1574 WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks); 1575 #endif 1576 } 1577 1578 static inline bool sock_owned_by_user(const struct sock *sk) 1579 { 1580 sock_owned_by_me(sk); 1581 return sk->sk_lock.owned; 1582 } 1583 1584 static inline bool sock_owned_by_user_nocheck(const struct sock *sk) 1585 { 1586 return sk->sk_lock.owned; 1587 } 1588 1589 /* no reclassification while locks are held */ 1590 static inline bool sock_allow_reclassification(const struct sock *csk) 1591 { 1592 struct sock *sk = (struct sock *)csk; 1593 1594 return !sk->sk_lock.owned && !spin_is_locked(&sk->sk_lock.slock); 1595 } 1596 1597 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 1598 struct proto *prot, int kern); 1599 void sk_free(struct sock *sk); 1600 void sk_destruct(struct sock *sk); 1601 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority); 1602 void sk_free_unlock_clone(struct sock *sk); 1603 1604 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 1605 gfp_t priority); 1606 void __sock_wfree(struct sk_buff *skb); 1607 void sock_wfree(struct sk_buff *skb); 1608 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size, 1609 gfp_t priority); 1610 void skb_orphan_partial(struct sk_buff *skb); 1611 void sock_rfree(struct sk_buff *skb); 1612 void sock_efree(struct sk_buff *skb); 1613 #ifdef CONFIG_INET 1614 void sock_edemux(struct sk_buff *skb); 1615 #else 1616 #define sock_edemux sock_efree 1617 #endif 1618 1619 int sock_setsockopt(struct socket *sock, int level, int op, 1620 char __user *optval, unsigned int optlen); 1621 1622 int sock_getsockopt(struct socket *sock, int level, int op, 1623 char __user *optval, int __user *optlen); 1624 int sock_gettstamp(struct socket *sock, void __user *userstamp, 1625 bool timeval, bool time32); 1626 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, 1627 int noblock, int *errcode); 1628 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 1629 unsigned long data_len, int noblock, 1630 int *errcode, int max_page_order); 1631 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority); 1632 void sock_kfree_s(struct sock *sk, void *mem, int size); 1633 void sock_kzfree_s(struct sock *sk, void *mem, int size); 1634 void sk_send_sigurg(struct sock *sk); 1635 1636 struct sockcm_cookie { 1637 u64 transmit_time; 1638 u32 mark; 1639 u16 tsflags; 1640 }; 1641 1642 static inline void sockcm_init(struct sockcm_cookie *sockc, 1643 const struct sock *sk) 1644 { 1645 *sockc = (struct sockcm_cookie) { .tsflags = sk->sk_tsflags }; 1646 } 1647 1648 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg, 1649 struct sockcm_cookie *sockc); 1650 int sock_cmsg_send(struct sock *sk, struct msghdr *msg, 1651 struct sockcm_cookie *sockc); 1652 1653 /* 1654 * Functions to fill in entries in struct proto_ops when a protocol 1655 * does not implement a particular function. 1656 */ 1657 int sock_no_bind(struct socket *, struct sockaddr *, int); 1658 int sock_no_connect(struct socket *, struct sockaddr *, int, int); 1659 int sock_no_socketpair(struct socket *, struct socket *); 1660 int sock_no_accept(struct socket *, struct socket *, int, bool); 1661 int sock_no_getname(struct socket *, struct sockaddr *, int); 1662 int sock_no_ioctl(struct socket *, unsigned int, unsigned long); 1663 int sock_no_listen(struct socket *, int); 1664 int sock_no_shutdown(struct socket *, int); 1665 int sock_no_getsockopt(struct socket *, int , int, char __user *, int __user *); 1666 int sock_no_setsockopt(struct socket *, int, int, char __user *, unsigned int); 1667 int sock_no_sendmsg(struct socket *, struct msghdr *, size_t); 1668 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len); 1669 int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int); 1670 int sock_no_mmap(struct file *file, struct socket *sock, 1671 struct vm_area_struct *vma); 1672 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, 1673 size_t size, int flags); 1674 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page, 1675 int offset, size_t size, int flags); 1676 1677 /* 1678 * Functions to fill in entries in struct proto_ops when a protocol 1679 * uses the inet style. 1680 */ 1681 int sock_common_getsockopt(struct socket *sock, int level, int optname, 1682 char __user *optval, int __user *optlen); 1683 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 1684 int flags); 1685 int sock_common_setsockopt(struct socket *sock, int level, int optname, 1686 char __user *optval, unsigned int optlen); 1687 int compat_sock_common_getsockopt(struct socket *sock, int level, 1688 int optname, char __user *optval, int __user *optlen); 1689 int compat_sock_common_setsockopt(struct socket *sock, int level, 1690 int optname, char __user *optval, unsigned int optlen); 1691 1692 void sk_common_release(struct sock *sk); 1693 1694 /* 1695 * Default socket callbacks and setup code 1696 */ 1697 1698 /* Initialise core socket variables */ 1699 void sock_init_data(struct socket *sock, struct sock *sk); 1700 1701 /* 1702 * Socket reference counting postulates. 1703 * 1704 * * Each user of socket SHOULD hold a reference count. 1705 * * Each access point to socket (an hash table bucket, reference from a list, 1706 * running timer, skb in flight MUST hold a reference count. 1707 * * When reference count hits 0, it means it will never increase back. 1708 * * When reference count hits 0, it means that no references from 1709 * outside exist to this socket and current process on current CPU 1710 * is last user and may/should destroy this socket. 1711 * * sk_free is called from any context: process, BH, IRQ. When 1712 * it is called, socket has no references from outside -> sk_free 1713 * may release descendant resources allocated by the socket, but 1714 * to the time when it is called, socket is NOT referenced by any 1715 * hash tables, lists etc. 1716 * * Packets, delivered from outside (from network or from another process) 1717 * and enqueued on receive/error queues SHOULD NOT grab reference count, 1718 * when they sit in queue. Otherwise, packets will leak to hole, when 1719 * socket is looked up by one cpu and unhasing is made by another CPU. 1720 * It is true for udp/raw, netlink (leak to receive and error queues), tcp 1721 * (leak to backlog). Packet socket does all the processing inside 1722 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets 1723 * use separate SMP lock, so that they are prone too. 1724 */ 1725 1726 /* Ungrab socket and destroy it, if it was the last reference. */ 1727 static inline void sock_put(struct sock *sk) 1728 { 1729 if (refcount_dec_and_test(&sk->sk_refcnt)) 1730 sk_free(sk); 1731 } 1732 /* Generic version of sock_put(), dealing with all sockets 1733 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...) 1734 */ 1735 void sock_gen_put(struct sock *sk); 1736 1737 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested, 1738 unsigned int trim_cap, bool refcounted); 1739 static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb, 1740 const int nested) 1741 { 1742 return __sk_receive_skb(sk, skb, nested, 1, true); 1743 } 1744 1745 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue) 1746 { 1747 /* sk_tx_queue_mapping accept only upto a 16-bit value */ 1748 if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX)) 1749 return; 1750 sk->sk_tx_queue_mapping = tx_queue; 1751 } 1752 1753 #define NO_QUEUE_MAPPING USHRT_MAX 1754 1755 static inline void sk_tx_queue_clear(struct sock *sk) 1756 { 1757 sk->sk_tx_queue_mapping = NO_QUEUE_MAPPING; 1758 } 1759 1760 static inline int sk_tx_queue_get(const struct sock *sk) 1761 { 1762 if (sk && sk->sk_tx_queue_mapping != NO_QUEUE_MAPPING) 1763 return sk->sk_tx_queue_mapping; 1764 1765 return -1; 1766 } 1767 1768 static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb) 1769 { 1770 #ifdef CONFIG_XPS 1771 if (skb_rx_queue_recorded(skb)) { 1772 u16 rx_queue = skb_get_rx_queue(skb); 1773 1774 if (WARN_ON_ONCE(rx_queue == NO_QUEUE_MAPPING)) 1775 return; 1776 1777 sk->sk_rx_queue_mapping = rx_queue; 1778 } 1779 #endif 1780 } 1781 1782 static inline void sk_rx_queue_clear(struct sock *sk) 1783 { 1784 #ifdef CONFIG_XPS 1785 sk->sk_rx_queue_mapping = NO_QUEUE_MAPPING; 1786 #endif 1787 } 1788 1789 #ifdef CONFIG_XPS 1790 static inline int sk_rx_queue_get(const struct sock *sk) 1791 { 1792 if (sk && sk->sk_rx_queue_mapping != NO_QUEUE_MAPPING) 1793 return sk->sk_rx_queue_mapping; 1794 1795 return -1; 1796 } 1797 #endif 1798 1799 static inline void sk_set_socket(struct sock *sk, struct socket *sock) 1800 { 1801 sk_tx_queue_clear(sk); 1802 sk->sk_socket = sock; 1803 } 1804 1805 static inline wait_queue_head_t *sk_sleep(struct sock *sk) 1806 { 1807 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0); 1808 return &rcu_dereference_raw(sk->sk_wq)->wait; 1809 } 1810 /* Detach socket from process context. 1811 * Announce socket dead, detach it from wait queue and inode. 1812 * Note that parent inode held reference count on this struct sock, 1813 * we do not release it in this function, because protocol 1814 * probably wants some additional cleanups or even continuing 1815 * to work with this socket (TCP). 1816 */ 1817 static inline void sock_orphan(struct sock *sk) 1818 { 1819 write_lock_bh(&sk->sk_callback_lock); 1820 sock_set_flag(sk, SOCK_DEAD); 1821 sk_set_socket(sk, NULL); 1822 sk->sk_wq = NULL; 1823 write_unlock_bh(&sk->sk_callback_lock); 1824 } 1825 1826 static inline void sock_graft(struct sock *sk, struct socket *parent) 1827 { 1828 WARN_ON(parent->sk); 1829 write_lock_bh(&sk->sk_callback_lock); 1830 rcu_assign_pointer(sk->sk_wq, &parent->wq); 1831 parent->sk = sk; 1832 sk_set_socket(sk, parent); 1833 sk->sk_uid = SOCK_INODE(parent)->i_uid; 1834 security_sock_graft(sk, parent); 1835 write_unlock_bh(&sk->sk_callback_lock); 1836 } 1837 1838 kuid_t sock_i_uid(struct sock *sk); 1839 unsigned long sock_i_ino(struct sock *sk); 1840 1841 static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk) 1842 { 1843 return sk ? sk->sk_uid : make_kuid(net->user_ns, 0); 1844 } 1845 1846 static inline u32 net_tx_rndhash(void) 1847 { 1848 u32 v = prandom_u32(); 1849 1850 return v ?: 1; 1851 } 1852 1853 static inline void sk_set_txhash(struct sock *sk) 1854 { 1855 sk->sk_txhash = net_tx_rndhash(); 1856 } 1857 1858 static inline void sk_rethink_txhash(struct sock *sk) 1859 { 1860 if (sk->sk_txhash) 1861 sk_set_txhash(sk); 1862 } 1863 1864 static inline struct dst_entry * 1865 __sk_dst_get(struct sock *sk) 1866 { 1867 return rcu_dereference_check(sk->sk_dst_cache, 1868 lockdep_sock_is_held(sk)); 1869 } 1870 1871 static inline struct dst_entry * 1872 sk_dst_get(struct sock *sk) 1873 { 1874 struct dst_entry *dst; 1875 1876 rcu_read_lock(); 1877 dst = rcu_dereference(sk->sk_dst_cache); 1878 if (dst && !atomic_inc_not_zero(&dst->__refcnt)) 1879 dst = NULL; 1880 rcu_read_unlock(); 1881 return dst; 1882 } 1883 1884 static inline void dst_negative_advice(struct sock *sk) 1885 { 1886 struct dst_entry *ndst, *dst = __sk_dst_get(sk); 1887 1888 sk_rethink_txhash(sk); 1889 1890 if (dst && dst->ops->negative_advice) { 1891 ndst = dst->ops->negative_advice(dst); 1892 1893 if (ndst != dst) { 1894 rcu_assign_pointer(sk->sk_dst_cache, ndst); 1895 sk_tx_queue_clear(sk); 1896 sk->sk_dst_pending_confirm = 0; 1897 } 1898 } 1899 } 1900 1901 static inline void 1902 __sk_dst_set(struct sock *sk, struct dst_entry *dst) 1903 { 1904 struct dst_entry *old_dst; 1905 1906 sk_tx_queue_clear(sk); 1907 sk->sk_dst_pending_confirm = 0; 1908 old_dst = rcu_dereference_protected(sk->sk_dst_cache, 1909 lockdep_sock_is_held(sk)); 1910 rcu_assign_pointer(sk->sk_dst_cache, dst); 1911 dst_release(old_dst); 1912 } 1913 1914 static inline void 1915 sk_dst_set(struct sock *sk, struct dst_entry *dst) 1916 { 1917 struct dst_entry *old_dst; 1918 1919 sk_tx_queue_clear(sk); 1920 sk->sk_dst_pending_confirm = 0; 1921 old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst); 1922 dst_release(old_dst); 1923 } 1924 1925 static inline void 1926 __sk_dst_reset(struct sock *sk) 1927 { 1928 __sk_dst_set(sk, NULL); 1929 } 1930 1931 static inline void 1932 sk_dst_reset(struct sock *sk) 1933 { 1934 sk_dst_set(sk, NULL); 1935 } 1936 1937 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie); 1938 1939 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie); 1940 1941 static inline void sk_dst_confirm(struct sock *sk) 1942 { 1943 if (!sk->sk_dst_pending_confirm) 1944 sk->sk_dst_pending_confirm = 1; 1945 } 1946 1947 static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n) 1948 { 1949 if (skb_get_dst_pending_confirm(skb)) { 1950 struct sock *sk = skb->sk; 1951 unsigned long now = jiffies; 1952 1953 /* avoid dirtying neighbour */ 1954 if (n->confirmed != now) 1955 n->confirmed = now; 1956 if (sk && sk->sk_dst_pending_confirm) 1957 sk->sk_dst_pending_confirm = 0; 1958 } 1959 } 1960 1961 bool sk_mc_loop(struct sock *sk); 1962 1963 static inline bool sk_can_gso(const struct sock *sk) 1964 { 1965 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type); 1966 } 1967 1968 void sk_setup_caps(struct sock *sk, struct dst_entry *dst); 1969 1970 static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags) 1971 { 1972 sk->sk_route_nocaps |= flags; 1973 sk->sk_route_caps &= ~flags; 1974 } 1975 1976 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb, 1977 struct iov_iter *from, char *to, 1978 int copy, int offset) 1979 { 1980 if (skb->ip_summed == CHECKSUM_NONE) { 1981 __wsum csum = 0; 1982 if (!csum_and_copy_from_iter_full(to, copy, &csum, from)) 1983 return -EFAULT; 1984 skb->csum = csum_block_add(skb->csum, csum, offset); 1985 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) { 1986 if (!copy_from_iter_full_nocache(to, copy, from)) 1987 return -EFAULT; 1988 } else if (!copy_from_iter_full(to, copy, from)) 1989 return -EFAULT; 1990 1991 return 0; 1992 } 1993 1994 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb, 1995 struct iov_iter *from, int copy) 1996 { 1997 int err, offset = skb->len; 1998 1999 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy), 2000 copy, offset); 2001 if (err) 2002 __skb_trim(skb, offset); 2003 2004 return err; 2005 } 2006 2007 static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from, 2008 struct sk_buff *skb, 2009 struct page *page, 2010 int off, int copy) 2011 { 2012 int err; 2013 2014 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off, 2015 copy, skb->len); 2016 if (err) 2017 return err; 2018 2019 skb->len += copy; 2020 skb->data_len += copy; 2021 skb->truesize += copy; 2022 sk_wmem_queued_add(sk, copy); 2023 sk_mem_charge(sk, copy); 2024 return 0; 2025 } 2026 2027 /** 2028 * sk_wmem_alloc_get - returns write allocations 2029 * @sk: socket 2030 * 2031 * Returns sk_wmem_alloc minus initial offset of one 2032 */ 2033 static inline int sk_wmem_alloc_get(const struct sock *sk) 2034 { 2035 return refcount_read(&sk->sk_wmem_alloc) - 1; 2036 } 2037 2038 /** 2039 * sk_rmem_alloc_get - returns read allocations 2040 * @sk: socket 2041 * 2042 * Returns sk_rmem_alloc 2043 */ 2044 static inline int sk_rmem_alloc_get(const struct sock *sk) 2045 { 2046 return atomic_read(&sk->sk_rmem_alloc); 2047 } 2048 2049 /** 2050 * sk_has_allocations - check if allocations are outstanding 2051 * @sk: socket 2052 * 2053 * Returns true if socket has write or read allocations 2054 */ 2055 static inline bool sk_has_allocations(const struct sock *sk) 2056 { 2057 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk); 2058 } 2059 2060 /** 2061 * skwq_has_sleeper - check if there are any waiting processes 2062 * @wq: struct socket_wq 2063 * 2064 * Returns true if socket_wq has waiting processes 2065 * 2066 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory 2067 * barrier call. They were added due to the race found within the tcp code. 2068 * 2069 * Consider following tcp code paths:: 2070 * 2071 * CPU1 CPU2 2072 * sys_select receive packet 2073 * ... ... 2074 * __add_wait_queue update tp->rcv_nxt 2075 * ... ... 2076 * tp->rcv_nxt check sock_def_readable 2077 * ... { 2078 * schedule rcu_read_lock(); 2079 * wq = rcu_dereference(sk->sk_wq); 2080 * if (wq && waitqueue_active(&wq->wait)) 2081 * wake_up_interruptible(&wq->wait) 2082 * ... 2083 * } 2084 * 2085 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay 2086 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1 2087 * could then endup calling schedule and sleep forever if there are no more 2088 * data on the socket. 2089 * 2090 */ 2091 static inline bool skwq_has_sleeper(struct socket_wq *wq) 2092 { 2093 return wq && wq_has_sleeper(&wq->wait); 2094 } 2095 2096 /** 2097 * sock_poll_wait - place memory barrier behind the poll_wait call. 2098 * @filp: file 2099 * @sock: socket to wait on 2100 * @p: poll_table 2101 * 2102 * See the comments in the wq_has_sleeper function. 2103 */ 2104 static inline void sock_poll_wait(struct file *filp, struct socket *sock, 2105 poll_table *p) 2106 { 2107 if (!poll_does_not_wait(p)) { 2108 poll_wait(filp, &sock->wq.wait, p); 2109 /* We need to be sure we are in sync with the 2110 * socket flags modification. 2111 * 2112 * This memory barrier is paired in the wq_has_sleeper. 2113 */ 2114 smp_mb(); 2115 } 2116 } 2117 2118 static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk) 2119 { 2120 if (sk->sk_txhash) { 2121 skb->l4_hash = 1; 2122 skb->hash = sk->sk_txhash; 2123 } 2124 } 2125 2126 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk); 2127 2128 /* 2129 * Queue a received datagram if it will fit. Stream and sequenced 2130 * protocols can't normally use this as they need to fit buffers in 2131 * and play with them. 2132 * 2133 * Inlined as it's very short and called for pretty much every 2134 * packet ever received. 2135 */ 2136 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk) 2137 { 2138 skb_orphan(skb); 2139 skb->sk = sk; 2140 skb->destructor = sock_rfree; 2141 atomic_add(skb->truesize, &sk->sk_rmem_alloc); 2142 sk_mem_charge(sk, skb->truesize); 2143 } 2144 2145 void sk_reset_timer(struct sock *sk, struct timer_list *timer, 2146 unsigned long expires); 2147 2148 void sk_stop_timer(struct sock *sk, struct timer_list *timer); 2149 2150 int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue, 2151 struct sk_buff *skb, unsigned int flags, 2152 void (*destructor)(struct sock *sk, 2153 struct sk_buff *skb)); 2154 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); 2155 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); 2156 2157 int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb); 2158 struct sk_buff *sock_dequeue_err_skb(struct sock *sk); 2159 2160 /* 2161 * Recover an error report and clear atomically 2162 */ 2163 2164 static inline int sock_error(struct sock *sk) 2165 { 2166 int err; 2167 if (likely(!sk->sk_err)) 2168 return 0; 2169 err = xchg(&sk->sk_err, 0); 2170 return -err; 2171 } 2172 2173 static inline unsigned long sock_wspace(struct sock *sk) 2174 { 2175 int amt = 0; 2176 2177 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { 2178 amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc); 2179 if (amt < 0) 2180 amt = 0; 2181 } 2182 return amt; 2183 } 2184 2185 /* Note: 2186 * We use sk->sk_wq_raw, from contexts knowing this 2187 * pointer is not NULL and cannot disappear/change. 2188 */ 2189 static inline void sk_set_bit(int nr, struct sock *sk) 2190 { 2191 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) && 2192 !sock_flag(sk, SOCK_FASYNC)) 2193 return; 2194 2195 set_bit(nr, &sk->sk_wq_raw->flags); 2196 } 2197 2198 static inline void sk_clear_bit(int nr, struct sock *sk) 2199 { 2200 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) && 2201 !sock_flag(sk, SOCK_FASYNC)) 2202 return; 2203 2204 clear_bit(nr, &sk->sk_wq_raw->flags); 2205 } 2206 2207 static inline void sk_wake_async(const struct sock *sk, int how, int band) 2208 { 2209 if (sock_flag(sk, SOCK_FASYNC)) { 2210 rcu_read_lock(); 2211 sock_wake_async(rcu_dereference(sk->sk_wq), how, band); 2212 rcu_read_unlock(); 2213 } 2214 } 2215 2216 /* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might 2217 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak. 2218 * Note: for send buffers, TCP works better if we can build two skbs at 2219 * minimum. 2220 */ 2221 #define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff))) 2222 2223 #define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2) 2224 #define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE 2225 2226 static inline void sk_stream_moderate_sndbuf(struct sock *sk) 2227 { 2228 u32 val; 2229 2230 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) 2231 return; 2232 2233 val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1); 2234 2235 WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF)); 2236 } 2237 2238 struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp, 2239 bool force_schedule); 2240 2241 /** 2242 * sk_page_frag - return an appropriate page_frag 2243 * @sk: socket 2244 * 2245 * Use the per task page_frag instead of the per socket one for 2246 * optimization when we know that we're in the normal context and owns 2247 * everything that's associated with %current. 2248 * 2249 * gfpflags_allow_blocking() isn't enough here as direct reclaim may nest 2250 * inside other socket operations and end up recursing into sk_page_frag() 2251 * while it's already in use. 2252 */ 2253 static inline struct page_frag *sk_page_frag(struct sock *sk) 2254 { 2255 if (gfpflags_normal_context(sk->sk_allocation)) 2256 return ¤t->task_frag; 2257 2258 return &sk->sk_frag; 2259 } 2260 2261 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag); 2262 2263 /* 2264 * Default write policy as shown to user space via poll/select/SIGIO 2265 */ 2266 static inline bool sock_writeable(const struct sock *sk) 2267 { 2268 return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1); 2269 } 2270 2271 static inline gfp_t gfp_any(void) 2272 { 2273 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL; 2274 } 2275 2276 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock) 2277 { 2278 return noblock ? 0 : sk->sk_rcvtimeo; 2279 } 2280 2281 static inline long sock_sndtimeo(const struct sock *sk, bool noblock) 2282 { 2283 return noblock ? 0 : sk->sk_sndtimeo; 2284 } 2285 2286 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len) 2287 { 2288 int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len); 2289 2290 return v ?: 1; 2291 } 2292 2293 /* Alas, with timeout socket operations are not restartable. 2294 * Compare this to poll(). 2295 */ 2296 static inline int sock_intr_errno(long timeo) 2297 { 2298 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR; 2299 } 2300 2301 struct sock_skb_cb { 2302 u32 dropcount; 2303 }; 2304 2305 /* Store sock_skb_cb at the end of skb->cb[] so protocol families 2306 * using skb->cb[] would keep using it directly and utilize its 2307 * alignement guarantee. 2308 */ 2309 #define SOCK_SKB_CB_OFFSET ((FIELD_SIZEOF(struct sk_buff, cb) - \ 2310 sizeof(struct sock_skb_cb))) 2311 2312 #define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \ 2313 SOCK_SKB_CB_OFFSET)) 2314 2315 #define sock_skb_cb_check_size(size) \ 2316 BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET) 2317 2318 static inline void 2319 sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb) 2320 { 2321 SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ? 2322 atomic_read(&sk->sk_drops) : 0; 2323 } 2324 2325 static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb) 2326 { 2327 int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs); 2328 2329 atomic_add(segs, &sk->sk_drops); 2330 } 2331 2332 static inline ktime_t sock_read_timestamp(struct sock *sk) 2333 { 2334 #if BITS_PER_LONG==32 2335 unsigned int seq; 2336 ktime_t kt; 2337 2338 do { 2339 seq = read_seqbegin(&sk->sk_stamp_seq); 2340 kt = sk->sk_stamp; 2341 } while (read_seqretry(&sk->sk_stamp_seq, seq)); 2342 2343 return kt; 2344 #else 2345 return READ_ONCE(sk->sk_stamp); 2346 #endif 2347 } 2348 2349 static inline void sock_write_timestamp(struct sock *sk, ktime_t kt) 2350 { 2351 #if BITS_PER_LONG==32 2352 write_seqlock(&sk->sk_stamp_seq); 2353 sk->sk_stamp = kt; 2354 write_sequnlock(&sk->sk_stamp_seq); 2355 #else 2356 WRITE_ONCE(sk->sk_stamp, kt); 2357 #endif 2358 } 2359 2360 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk, 2361 struct sk_buff *skb); 2362 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk, 2363 struct sk_buff *skb); 2364 2365 static inline void 2366 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb) 2367 { 2368 ktime_t kt = skb->tstamp; 2369 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb); 2370 2371 /* 2372 * generate control messages if 2373 * - receive time stamping in software requested 2374 * - software time stamp available and wanted 2375 * - hardware time stamps available and wanted 2376 */ 2377 if (sock_flag(sk, SOCK_RCVTSTAMP) || 2378 (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) || 2379 (kt && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) || 2380 (hwtstamps->hwtstamp && 2381 (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE))) 2382 __sock_recv_timestamp(msg, sk, skb); 2383 else 2384 sock_write_timestamp(sk, kt); 2385 2386 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid) 2387 __sock_recv_wifi_status(msg, sk, skb); 2388 } 2389 2390 void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk, 2391 struct sk_buff *skb); 2392 2393 #define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC) 2394 static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk, 2395 struct sk_buff *skb) 2396 { 2397 #define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \ 2398 (1UL << SOCK_RCVTSTAMP)) 2399 #define TSFLAGS_ANY (SOF_TIMESTAMPING_SOFTWARE | \ 2400 SOF_TIMESTAMPING_RAW_HARDWARE) 2401 2402 if (sk->sk_flags & FLAGS_TS_OR_DROPS || sk->sk_tsflags & TSFLAGS_ANY) 2403 __sock_recv_ts_and_drops(msg, sk, skb); 2404 else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP))) 2405 sock_write_timestamp(sk, skb->tstamp); 2406 else if (unlikely(sk->sk_stamp == SK_DEFAULT_STAMP)) 2407 sock_write_timestamp(sk, 0); 2408 } 2409 2410 void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags); 2411 2412 /** 2413 * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped 2414 * @sk: socket sending this packet 2415 * @tsflags: timestamping flags to use 2416 * @tx_flags: completed with instructions for time stamping 2417 * @tskey: filled in with next sk_tskey (not for TCP, which uses seqno) 2418 * 2419 * Note: callers should take care of initial ``*tx_flags`` value (usually 0) 2420 */ 2421 static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags, 2422 __u8 *tx_flags, __u32 *tskey) 2423 { 2424 if (unlikely(tsflags)) { 2425 __sock_tx_timestamp(tsflags, tx_flags); 2426 if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey && 2427 tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK) 2428 *tskey = sk->sk_tskey++; 2429 } 2430 if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS))) 2431 *tx_flags |= SKBTX_WIFI_STATUS; 2432 } 2433 2434 static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags, 2435 __u8 *tx_flags) 2436 { 2437 _sock_tx_timestamp(sk, tsflags, tx_flags, NULL); 2438 } 2439 2440 static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags) 2441 { 2442 _sock_tx_timestamp(skb->sk, tsflags, &skb_shinfo(skb)->tx_flags, 2443 &skb_shinfo(skb)->tskey); 2444 } 2445 2446 /** 2447 * sk_eat_skb - Release a skb if it is no longer needed 2448 * @sk: socket to eat this skb from 2449 * @skb: socket buffer to eat 2450 * 2451 * This routine must be called with interrupts disabled or with the socket 2452 * locked so that the sk_buff queue operation is ok. 2453 */ 2454 DECLARE_STATIC_KEY_FALSE(tcp_rx_skb_cache_key); 2455 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb) 2456 { 2457 __skb_unlink(skb, &sk->sk_receive_queue); 2458 if (static_branch_unlikely(&tcp_rx_skb_cache_key) && 2459 !sk->sk_rx_skb_cache) { 2460 sk->sk_rx_skb_cache = skb; 2461 skb_orphan(skb); 2462 return; 2463 } 2464 __kfree_skb(skb); 2465 } 2466 2467 static inline 2468 struct net *sock_net(const struct sock *sk) 2469 { 2470 return read_pnet(&sk->sk_net); 2471 } 2472 2473 static inline 2474 void sock_net_set(struct sock *sk, struct net *net) 2475 { 2476 write_pnet(&sk->sk_net, net); 2477 } 2478 2479 static inline struct sock *skb_steal_sock(struct sk_buff *skb) 2480 { 2481 if (skb->sk) { 2482 struct sock *sk = skb->sk; 2483 2484 skb->destructor = NULL; 2485 skb->sk = NULL; 2486 return sk; 2487 } 2488 return NULL; 2489 } 2490 2491 /* This helper checks if a socket is a full socket, 2492 * ie _not_ a timewait or request socket. 2493 */ 2494 static inline bool sk_fullsock(const struct sock *sk) 2495 { 2496 return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV); 2497 } 2498 2499 /* Checks if this SKB belongs to an HW offloaded socket 2500 * and whether any SW fallbacks are required based on dev. 2501 * Check decrypted mark in case skb_orphan() cleared socket. 2502 */ 2503 static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb, 2504 struct net_device *dev) 2505 { 2506 #ifdef CONFIG_SOCK_VALIDATE_XMIT 2507 struct sock *sk = skb->sk; 2508 2509 if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) { 2510 skb = sk->sk_validate_xmit_skb(sk, dev, skb); 2511 #ifdef CONFIG_TLS_DEVICE 2512 } else if (unlikely(skb->decrypted)) { 2513 pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n"); 2514 kfree_skb(skb); 2515 skb = NULL; 2516 #endif 2517 } 2518 #endif 2519 2520 return skb; 2521 } 2522 2523 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV 2524 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE) 2525 */ 2526 static inline bool sk_listener(const struct sock *sk) 2527 { 2528 return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV); 2529 } 2530 2531 void sock_enable_timestamp(struct sock *sk, int flag); 2532 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level, 2533 int type); 2534 2535 bool sk_ns_capable(const struct sock *sk, 2536 struct user_namespace *user_ns, int cap); 2537 bool sk_capable(const struct sock *sk, int cap); 2538 bool sk_net_capable(const struct sock *sk, int cap); 2539 2540 void sk_get_meminfo(const struct sock *sk, u32 *meminfo); 2541 2542 /* Take into consideration the size of the struct sk_buff overhead in the 2543 * determination of these values, since that is non-constant across 2544 * platforms. This makes socket queueing behavior and performance 2545 * not depend upon such differences. 2546 */ 2547 #define _SK_MEM_PACKETS 256 2548 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256) 2549 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 2550 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 2551 2552 extern __u32 sysctl_wmem_max; 2553 extern __u32 sysctl_rmem_max; 2554 2555 extern int sysctl_tstamp_allow_data; 2556 extern int sysctl_optmem_max; 2557 2558 extern __u32 sysctl_wmem_default; 2559 extern __u32 sysctl_rmem_default; 2560 2561 DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key); 2562 2563 static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto) 2564 { 2565 /* Does this proto have per netns sysctl_wmem ? */ 2566 if (proto->sysctl_wmem_offset) 2567 return *(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset); 2568 2569 return *proto->sysctl_wmem; 2570 } 2571 2572 static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto) 2573 { 2574 /* Does this proto have per netns sysctl_rmem ? */ 2575 if (proto->sysctl_rmem_offset) 2576 return *(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset); 2577 2578 return *proto->sysctl_rmem; 2579 } 2580 2581 /* Default TCP Small queue budget is ~1 ms of data (1sec >> 10) 2582 * Some wifi drivers need to tweak it to get more chunks. 2583 * They can use this helper from their ndo_start_xmit() 2584 */ 2585 static inline void sk_pacing_shift_update(struct sock *sk, int val) 2586 { 2587 if (!sk || !sk_fullsock(sk) || sk->sk_pacing_shift == val) 2588 return; 2589 sk->sk_pacing_shift = val; 2590 } 2591 2592 /* if a socket is bound to a device, check that the given device 2593 * index is either the same or that the socket is bound to an L3 2594 * master device and the given device index is also enslaved to 2595 * that L3 master 2596 */ 2597 static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif) 2598 { 2599 int mdif; 2600 2601 if (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dif) 2602 return true; 2603 2604 mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif); 2605 if (mdif && mdif == sk->sk_bound_dev_if) 2606 return true; 2607 2608 return false; 2609 } 2610 2611 #endif /* _SOCK_H */ 2612