1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* Multipath TCP 3 * 4 * Copyright (c) 2017 - 2019, Intel Corporation. 5 */ 6 7 #ifndef __MPTCP_PROTOCOL_H 8 #define __MPTCP_PROTOCOL_H 9 10 #include <linux/random.h> 11 #include <net/tcp.h> 12 #include <net/inet_connection_sock.h> 13 #include <uapi/linux/mptcp.h> 14 #include <net/genetlink.h> 15 16 #include "mptcp_pm_gen.h" 17 18 #define MPTCP_SUPPORTED_VERSION 1 19 20 /* MPTCP option bits */ 21 #define OPTION_MPTCP_MPC_SYN BIT(0) 22 #define OPTION_MPTCP_MPC_SYNACK BIT(1) 23 #define OPTION_MPTCP_MPC_ACK BIT(2) 24 #define OPTION_MPTCP_MPJ_SYN BIT(3) 25 #define OPTION_MPTCP_MPJ_SYNACK BIT(4) 26 #define OPTION_MPTCP_MPJ_ACK BIT(5) 27 #define OPTION_MPTCP_ADD_ADDR BIT(6) 28 #define OPTION_MPTCP_RM_ADDR BIT(7) 29 #define OPTION_MPTCP_FASTCLOSE BIT(8) 30 #define OPTION_MPTCP_PRIO BIT(9) 31 #define OPTION_MPTCP_RST BIT(10) 32 #define OPTION_MPTCP_DSS BIT(11) 33 #define OPTION_MPTCP_FAIL BIT(12) 34 35 #define OPTION_MPTCP_CSUMREQD BIT(13) 36 37 #define OPTIONS_MPTCP_MPC (OPTION_MPTCP_MPC_SYN | OPTION_MPTCP_MPC_SYNACK | \ 38 OPTION_MPTCP_MPC_ACK) 39 #define OPTIONS_MPTCP_MPJ (OPTION_MPTCP_MPJ_SYN | OPTION_MPTCP_MPJ_SYNACK | \ 40 OPTION_MPTCP_MPJ_ACK) 41 42 /* MPTCP option subtypes */ 43 #define MPTCPOPT_MP_CAPABLE 0 44 #define MPTCPOPT_MP_JOIN 1 45 #define MPTCPOPT_DSS 2 46 #define MPTCPOPT_ADD_ADDR 3 47 #define MPTCPOPT_RM_ADDR 4 48 #define MPTCPOPT_MP_PRIO 5 49 #define MPTCPOPT_MP_FAIL 6 50 #define MPTCPOPT_MP_FASTCLOSE 7 51 #define MPTCPOPT_RST 8 52 53 /* MPTCP suboption lengths */ 54 #define TCPOLEN_MPTCP_MPC_SYN 4 55 #define TCPOLEN_MPTCP_MPC_SYNACK 12 56 #define TCPOLEN_MPTCP_MPC_ACK 20 57 #define TCPOLEN_MPTCP_MPC_ACK_DATA 22 58 #define TCPOLEN_MPTCP_MPJ_SYN 12 59 #define TCPOLEN_MPTCP_MPJ_SYNACK 16 60 #define TCPOLEN_MPTCP_MPJ_ACK 24 61 #define TCPOLEN_MPTCP_DSS_BASE 4 62 #define TCPOLEN_MPTCP_DSS_ACK32 4 63 #define TCPOLEN_MPTCP_DSS_ACK64 8 64 #define TCPOLEN_MPTCP_DSS_MAP32 10 65 #define TCPOLEN_MPTCP_DSS_MAP64 14 66 #define TCPOLEN_MPTCP_DSS_CHECKSUM 2 67 #define TCPOLEN_MPTCP_ADD_ADDR 16 68 #define TCPOLEN_MPTCP_ADD_ADDR_PORT 18 69 #define TCPOLEN_MPTCP_ADD_ADDR_BASE 8 70 #define TCPOLEN_MPTCP_ADD_ADDR_BASE_PORT 10 71 #define TCPOLEN_MPTCP_ADD_ADDR6 28 72 #define TCPOLEN_MPTCP_ADD_ADDR6_PORT 30 73 #define TCPOLEN_MPTCP_ADD_ADDR6_BASE 20 74 #define TCPOLEN_MPTCP_ADD_ADDR6_BASE_PORT 22 75 #define TCPOLEN_MPTCP_PORT_LEN 2 76 #define TCPOLEN_MPTCP_PORT_ALIGN 2 77 #define TCPOLEN_MPTCP_RM_ADDR_BASE 3 78 #define TCPOLEN_MPTCP_PRIO 3 79 #define TCPOLEN_MPTCP_PRIO_ALIGN 4 80 #define TCPOLEN_MPTCP_FASTCLOSE 12 81 #define TCPOLEN_MPTCP_RST 4 82 #define TCPOLEN_MPTCP_FAIL 12 83 84 #define TCPOLEN_MPTCP_MPC_ACK_DATA_CSUM (TCPOLEN_MPTCP_DSS_CHECKSUM + TCPOLEN_MPTCP_MPC_ACK_DATA) 85 86 /* MPTCP MP_JOIN flags */ 87 #define MPTCPOPT_BACKUP BIT(0) 88 #define MPTCPOPT_THMAC_LEN 8 89 90 /* MPTCP MP_CAPABLE flags */ 91 #define MPTCP_VERSION_MASK (0x0F) 92 #define MPTCP_CAP_CHECKSUM_REQD BIT(7) 93 #define MPTCP_CAP_EXTENSIBILITY BIT(6) 94 #define MPTCP_CAP_DENY_JOIN_ID0 BIT(5) 95 #define MPTCP_CAP_HMAC_SHA256 BIT(0) 96 #define MPTCP_CAP_FLAG_MASK (0x1F) 97 98 /* MPTCP DSS flags */ 99 #define MPTCP_DSS_DATA_FIN BIT(4) 100 #define MPTCP_DSS_DSN64 BIT(3) 101 #define MPTCP_DSS_HAS_MAP BIT(2) 102 #define MPTCP_DSS_ACK64 BIT(1) 103 #define MPTCP_DSS_HAS_ACK BIT(0) 104 #define MPTCP_DSS_FLAG_MASK (0x1F) 105 106 /* MPTCP ADD_ADDR flags */ 107 #define MPTCP_ADDR_ECHO BIT(0) 108 109 /* MPTCP MP_PRIO flags */ 110 #define MPTCP_PRIO_BKUP BIT(0) 111 112 /* MPTCP TCPRST flags */ 113 #define MPTCP_RST_TRANSIENT BIT(0) 114 115 /* MPTCP socket atomic flags */ 116 #define MPTCP_NOSPACE 1 117 #define MPTCP_WORK_RTX 2 118 #define MPTCP_FALLBACK_DONE 4 119 #define MPTCP_WORK_CLOSE_SUBFLOW 5 120 121 /* MPTCP socket release cb flags */ 122 #define MPTCP_PUSH_PENDING 1 123 #define MPTCP_CLEAN_UNA 2 124 #define MPTCP_ERROR_REPORT 3 125 #define MPTCP_RETRANSMIT 4 126 #define MPTCP_FLUSH_JOIN_LIST 5 127 #define MPTCP_SYNC_STATE 6 128 #define MPTCP_SYNC_SNDBUF 7 129 130 struct mptcp_skb_cb { 131 u64 map_seq; 132 u64 end_seq; 133 u32 offset; 134 u8 has_rxtstamp:1; 135 }; 136 137 #define MPTCP_SKB_CB(__skb) ((struct mptcp_skb_cb *)&((__skb)->cb[0])) 138 139 static inline bool before64(__u64 seq1, __u64 seq2) 140 { 141 return (__s64)(seq1 - seq2) < 0; 142 } 143 144 #define after64(seq2, seq1) before64(seq1, seq2) 145 146 struct mptcp_options_received { 147 u64 sndr_key; 148 u64 rcvr_key; 149 u64 data_ack; 150 u64 data_seq; 151 u32 subflow_seq; 152 u16 data_len; 153 __sum16 csum; 154 u16 suboptions; 155 u32 token; 156 u32 nonce; 157 u16 use_map:1, 158 dsn64:1, 159 data_fin:1, 160 use_ack:1, 161 ack64:1, 162 mpc_map:1, 163 reset_reason:4, 164 reset_transient:1, 165 echo:1, 166 backup:1, 167 deny_join_id0:1, 168 __unused:2; 169 u8 join_id; 170 u64 thmac; 171 u8 hmac[MPTCPOPT_HMAC_LEN]; 172 struct mptcp_addr_info addr; 173 struct mptcp_rm_list rm_list; 174 u64 ahmac; 175 u64 fail_seq; 176 }; 177 178 static inline __be32 mptcp_option(u8 subopt, u8 len, u8 nib, u8 field) 179 { 180 return htonl((TCPOPT_MPTCP << 24) | (len << 16) | (subopt << 12) | 181 ((nib & 0xF) << 8) | field); 182 } 183 184 enum mptcp_pm_status { 185 MPTCP_PM_ADD_ADDR_RECEIVED, 186 MPTCP_PM_ADD_ADDR_SEND_ACK, 187 MPTCP_PM_RM_ADDR_RECEIVED, 188 MPTCP_PM_ESTABLISHED, 189 MPTCP_PM_SUBFLOW_ESTABLISHED, 190 MPTCP_PM_ALREADY_ESTABLISHED, /* persistent status, set after ESTABLISHED event */ 191 MPTCP_PM_MPC_ENDPOINT_ACCOUNTED /* persistent status, set after MPC local address is 192 * accounted int id_avail_bitmap 193 */ 194 }; 195 196 enum mptcp_pm_type { 197 MPTCP_PM_TYPE_KERNEL = 0, 198 MPTCP_PM_TYPE_USERSPACE, 199 200 __MPTCP_PM_TYPE_NR, 201 __MPTCP_PM_TYPE_MAX = __MPTCP_PM_TYPE_NR - 1, 202 }; 203 204 /* Status bits below MPTCP_PM_ALREADY_ESTABLISHED need pm worker actions */ 205 #define MPTCP_PM_WORK_MASK ((1 << MPTCP_PM_ALREADY_ESTABLISHED) - 1) 206 207 enum mptcp_addr_signal_status { 208 MPTCP_ADD_ADDR_SIGNAL, 209 MPTCP_ADD_ADDR_ECHO, 210 MPTCP_RM_ADDR_SIGNAL, 211 }; 212 213 /* max value of mptcp_addr_info.id */ 214 #define MPTCP_PM_MAX_ADDR_ID U8_MAX 215 216 struct mptcp_pm_data { 217 struct mptcp_addr_info local; 218 struct mptcp_addr_info remote; 219 struct list_head anno_list; 220 struct list_head userspace_pm_local_addr_list; 221 222 spinlock_t lock; /*protects the whole PM data */ 223 224 u8 addr_signal; 225 bool server_side; 226 bool work_pending; 227 bool accept_addr; 228 bool accept_subflow; 229 bool remote_deny_join_id0; 230 u8 add_addr_signaled; 231 u8 add_addr_accepted; 232 u8 local_addr_used; 233 u8 pm_type; 234 u8 subflows; 235 u8 status; 236 DECLARE_BITMAP(id_avail_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); 237 struct mptcp_rm_list rm_list_tx; 238 struct mptcp_rm_list rm_list_rx; 239 }; 240 241 struct mptcp_pm_addr_entry { 242 struct list_head list; 243 struct mptcp_addr_info addr; 244 u8 flags; 245 int ifindex; 246 struct socket *lsk; 247 }; 248 249 struct mptcp_data_frag { 250 struct list_head list; 251 u64 data_seq; 252 u16 data_len; 253 u16 offset; 254 u16 overhead; 255 u16 already_sent; 256 struct page *page; 257 }; 258 259 /* MPTCP connection sock */ 260 struct mptcp_sock { 261 /* inet_connection_sock must be the first member */ 262 struct inet_connection_sock sk; 263 u64 local_key; /* protected by the first subflow socket lock 264 * lockless access read 265 */ 266 u64 remote_key; /* same as above */ 267 u64 write_seq; 268 u64 bytes_sent; 269 u64 snd_nxt; 270 u64 bytes_received; 271 u64 ack_seq; 272 atomic64_t rcv_wnd_sent; 273 u64 rcv_data_fin_seq; 274 u64 bytes_retrans; 275 u64 bytes_consumed; 276 int rmem_fwd_alloc; 277 int snd_burst; 278 int old_wspace; 279 u64 recovery_snd_nxt; /* in recovery mode accept up to this seq; 280 * recovery related fields are under data_lock 281 * protection 282 */ 283 u64 bytes_acked; 284 u64 snd_una; 285 u64 wnd_end; 286 unsigned long timer_ival; 287 u32 token; 288 int rmem_released; 289 unsigned long flags; 290 unsigned long cb_flags; 291 unsigned long push_pending; 292 bool recovery; /* closing subflow write queue reinjected */ 293 bool can_ack; 294 bool fully_established; 295 bool rcv_data_fin; 296 bool snd_data_fin_enable; 297 bool rcv_fastclose; 298 bool use_64bit_ack; /* Set when we received a 64-bit DSN */ 299 bool csum_enabled; 300 bool allow_infinite_fallback; 301 u8 pending_state; /* A subflow asked to set this sk_state, 302 * protected by the msk data lock 303 */ 304 u8 mpc_endpoint_id; 305 u8 recvmsg_inq:1, 306 cork:1, 307 nodelay:1, 308 fastopening:1, 309 in_accept_queue:1, 310 free_first:1; 311 struct work_struct work; 312 struct sk_buff *ooo_last_skb; 313 struct rb_root out_of_order_queue; 314 struct sk_buff_head receive_queue; 315 struct list_head conn_list; 316 struct list_head rtx_queue; 317 struct mptcp_data_frag *first_pending; 318 struct list_head join_list; 319 struct sock *first; /* The mptcp ops can safely dereference, using suitable 320 * ONCE annotation, the subflow outside the socket 321 * lock as such sock is freed after close(). 322 */ 323 struct mptcp_pm_data pm; 324 struct mptcp_sched_ops *sched; 325 struct { 326 u32 space; /* bytes copied in last measurement window */ 327 u32 copied; /* bytes copied in this measurement window */ 328 u64 time; /* start time of measurement window */ 329 u64 rtt_us; /* last maximum rtt of subflows */ 330 } rcvq_space; 331 u8 scaling_ratio; 332 333 u32 subflow_id; 334 u32 setsockopt_seq; 335 char ca_name[TCP_CA_NAME_MAX]; 336 }; 337 338 #define mptcp_data_lock(sk) spin_lock_bh(&(sk)->sk_lock.slock) 339 #define mptcp_data_unlock(sk) spin_unlock_bh(&(sk)->sk_lock.slock) 340 341 #define mptcp_for_each_subflow(__msk, __subflow) \ 342 list_for_each_entry(__subflow, &((__msk)->conn_list), node) 343 #define mptcp_for_each_subflow_safe(__msk, __subflow, __tmp) \ 344 list_for_each_entry_safe(__subflow, __tmp, &((__msk)->conn_list), node) 345 346 static inline void msk_owned_by_me(const struct mptcp_sock *msk) 347 { 348 sock_owned_by_me((const struct sock *)msk); 349 } 350 351 #define mptcp_sk(ptr) container_of_const(ptr, struct mptcp_sock, sk.icsk_inet.sk) 352 353 /* the msk socket don't use the backlog, also account for the bulk 354 * free memory 355 */ 356 static inline int __mptcp_rmem(const struct sock *sk) 357 { 358 return atomic_read(&sk->sk_rmem_alloc) - READ_ONCE(mptcp_sk(sk)->rmem_released); 359 } 360 361 static inline int mptcp_win_from_space(const struct sock *sk, int space) 362 { 363 return __tcp_win_from_space(mptcp_sk(sk)->scaling_ratio, space); 364 } 365 366 static inline int __mptcp_space(const struct sock *sk) 367 { 368 return mptcp_win_from_space(sk, READ_ONCE(sk->sk_rcvbuf) - __mptcp_rmem(sk)); 369 } 370 371 static inline struct mptcp_data_frag *mptcp_send_head(const struct sock *sk) 372 { 373 const struct mptcp_sock *msk = mptcp_sk(sk); 374 375 return READ_ONCE(msk->first_pending); 376 } 377 378 static inline struct mptcp_data_frag *mptcp_send_next(struct sock *sk) 379 { 380 struct mptcp_sock *msk = mptcp_sk(sk); 381 struct mptcp_data_frag *cur; 382 383 cur = msk->first_pending; 384 return list_is_last(&cur->list, &msk->rtx_queue) ? NULL : 385 list_next_entry(cur, list); 386 } 387 388 static inline struct mptcp_data_frag *mptcp_pending_tail(const struct sock *sk) 389 { 390 const struct mptcp_sock *msk = mptcp_sk(sk); 391 392 if (!msk->first_pending) 393 return NULL; 394 395 if (WARN_ON_ONCE(list_empty(&msk->rtx_queue))) 396 return NULL; 397 398 return list_last_entry(&msk->rtx_queue, struct mptcp_data_frag, list); 399 } 400 401 static inline struct mptcp_data_frag *mptcp_rtx_head(struct sock *sk) 402 { 403 struct mptcp_sock *msk = mptcp_sk(sk); 404 405 if (msk->snd_una == msk->snd_nxt) 406 return NULL; 407 408 return list_first_entry_or_null(&msk->rtx_queue, struct mptcp_data_frag, list); 409 } 410 411 struct csum_pseudo_header { 412 __be64 data_seq; 413 __be32 subflow_seq; 414 __be16 data_len; 415 __sum16 csum; 416 }; 417 418 struct mptcp_subflow_request_sock { 419 struct tcp_request_sock sk; 420 u16 mp_capable : 1, 421 mp_join : 1, 422 backup : 1, 423 csum_reqd : 1, 424 allow_join_id0 : 1; 425 u8 local_id; 426 u8 remote_id; 427 u64 local_key; 428 u64 idsn; 429 u32 token; 430 u32 ssn_offset; 431 u64 thmac; 432 u32 local_nonce; 433 u32 remote_nonce; 434 struct mptcp_sock *msk; 435 struct hlist_nulls_node token_node; 436 }; 437 438 static inline struct mptcp_subflow_request_sock * 439 mptcp_subflow_rsk(const struct request_sock *rsk) 440 { 441 return (struct mptcp_subflow_request_sock *)rsk; 442 } 443 444 struct mptcp_delegated_action { 445 struct napi_struct napi; 446 struct list_head head; 447 }; 448 449 DECLARE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions); 450 451 #define MPTCP_DELEGATE_SCHEDULED 0 452 #define MPTCP_DELEGATE_SEND 1 453 #define MPTCP_DELEGATE_ACK 2 454 #define MPTCP_DELEGATE_SNDBUF 3 455 456 #define MPTCP_DELEGATE_ACTIONS_MASK (~BIT(MPTCP_DELEGATE_SCHEDULED)) 457 /* MPTCP subflow context */ 458 struct mptcp_subflow_context { 459 struct list_head node;/* conn_list of subflows */ 460 461 struct_group(reset, 462 463 unsigned long avg_pacing_rate; /* protected by msk socket lock */ 464 u64 local_key; 465 u64 remote_key; 466 u64 idsn; 467 u64 map_seq; 468 u32 snd_isn; 469 u32 token; 470 u32 rel_write_seq; 471 u32 map_subflow_seq; 472 u32 ssn_offset; 473 u32 map_data_len; 474 __wsum map_data_csum; 475 u32 map_csum_len; 476 u32 request_mptcp : 1, /* send MP_CAPABLE */ 477 request_join : 1, /* send MP_JOIN */ 478 request_bkup : 1, 479 mp_capable : 1, /* remote is MPTCP capable */ 480 mp_join : 1, /* remote is JOINing */ 481 fully_established : 1, /* path validated */ 482 pm_notified : 1, /* PM hook called for established status */ 483 conn_finished : 1, 484 map_valid : 1, 485 map_csum_reqd : 1, 486 map_data_fin : 1, 487 mpc_map : 1, 488 backup : 1, 489 send_mp_prio : 1, 490 send_mp_fail : 1, 491 send_fastclose : 1, 492 send_infinite_map : 1, 493 remote_key_valid : 1, /* received the peer key from */ 494 disposable : 1, /* ctx can be free at ulp release time */ 495 stale : 1, /* unable to snd/rcv data, do not use for xmit */ 496 local_id_valid : 1, /* local_id is correctly initialized */ 497 valid_csum_seen : 1, /* at least one csum validated */ 498 is_mptfo : 1, /* subflow is doing TFO */ 499 __unused : 9; 500 bool data_avail; 501 bool scheduled; 502 u32 remote_nonce; 503 u64 thmac; 504 u32 local_nonce; 505 u32 remote_token; 506 union { 507 u8 hmac[MPTCPOPT_HMAC_LEN]; /* MPJ subflow only */ 508 u64 iasn; /* initial ack sequence number, MPC subflows only */ 509 }; 510 u8 local_id; 511 u8 remote_id; 512 u8 reset_seen:1; 513 u8 reset_transient:1; 514 u8 reset_reason:4; 515 u8 stale_count; 516 517 u32 subflow_id; 518 519 long delegated_status; 520 unsigned long fail_tout; 521 522 ); 523 524 struct list_head delegated_node; /* link into delegated_action, protected by local BH */ 525 526 u32 setsockopt_seq; 527 u32 stale_rcv_tstamp; 528 int cached_sndbuf; /* sndbuf size when last synced with the msk sndbuf, 529 * protected by the msk socket lock 530 */ 531 532 struct sock *tcp_sock; /* tcp sk backpointer */ 533 struct sock *conn; /* parent mptcp_sock */ 534 const struct inet_connection_sock_af_ops *icsk_af_ops; 535 void (*tcp_state_change)(struct sock *sk); 536 void (*tcp_error_report)(struct sock *sk); 537 538 struct rcu_head rcu; 539 }; 540 541 static inline struct mptcp_subflow_context * 542 mptcp_subflow_ctx(const struct sock *sk) 543 { 544 struct inet_connection_sock *icsk = inet_csk(sk); 545 546 /* Use RCU on icsk_ulp_data only for sock diag code */ 547 return (__force struct mptcp_subflow_context *)icsk->icsk_ulp_data; 548 } 549 550 static inline struct sock * 551 mptcp_subflow_tcp_sock(const struct mptcp_subflow_context *subflow) 552 { 553 return subflow->tcp_sock; 554 } 555 556 static inline void 557 mptcp_subflow_ctx_reset(struct mptcp_subflow_context *subflow) 558 { 559 memset(&subflow->reset, 0, sizeof(subflow->reset)); 560 subflow->request_mptcp = 1; 561 } 562 563 static inline u64 564 mptcp_subflow_get_map_offset(const struct mptcp_subflow_context *subflow) 565 { 566 return tcp_sk(mptcp_subflow_tcp_sock(subflow))->copied_seq - 567 subflow->ssn_offset - 568 subflow->map_subflow_seq; 569 } 570 571 static inline u64 572 mptcp_subflow_get_mapped_dsn(const struct mptcp_subflow_context *subflow) 573 { 574 return subflow->map_seq + mptcp_subflow_get_map_offset(subflow); 575 } 576 577 void mptcp_subflow_process_delegated(struct sock *ssk, long actions); 578 579 static inline void mptcp_subflow_delegate(struct mptcp_subflow_context *subflow, int action) 580 { 581 long old, set_bits = BIT(MPTCP_DELEGATE_SCHEDULED) | BIT(action); 582 struct mptcp_delegated_action *delegated; 583 bool schedule; 584 585 /* the caller held the subflow bh socket lock */ 586 lockdep_assert_in_softirq(); 587 588 /* The implied barrier pairs with tcp_release_cb_override() 589 * mptcp_napi_poll(), and ensures the below list check sees list 590 * updates done prior to delegated status bits changes 591 */ 592 old = set_mask_bits(&subflow->delegated_status, 0, set_bits); 593 if (!(old & BIT(MPTCP_DELEGATE_SCHEDULED))) { 594 if (WARN_ON_ONCE(!list_empty(&subflow->delegated_node))) 595 return; 596 597 delegated = this_cpu_ptr(&mptcp_delegated_actions); 598 schedule = list_empty(&delegated->head); 599 list_add_tail(&subflow->delegated_node, &delegated->head); 600 sock_hold(mptcp_subflow_tcp_sock(subflow)); 601 if (schedule) 602 napi_schedule(&delegated->napi); 603 } 604 } 605 606 static inline struct mptcp_subflow_context * 607 mptcp_subflow_delegated_next(struct mptcp_delegated_action *delegated) 608 { 609 struct mptcp_subflow_context *ret; 610 611 if (list_empty(&delegated->head)) 612 return NULL; 613 614 ret = list_first_entry(&delegated->head, struct mptcp_subflow_context, delegated_node); 615 list_del_init(&ret->delegated_node); 616 return ret; 617 } 618 619 int mptcp_is_enabled(const struct net *net); 620 unsigned int mptcp_get_add_addr_timeout(const struct net *net); 621 int mptcp_is_checksum_enabled(const struct net *net); 622 int mptcp_allow_join_id0(const struct net *net); 623 unsigned int mptcp_stale_loss_cnt(const struct net *net); 624 unsigned int mptcp_close_timeout(const struct sock *sk); 625 int mptcp_get_pm_type(const struct net *net); 626 const char *mptcp_get_scheduler(const struct net *net); 627 void mptcp_subflow_fully_established(struct mptcp_subflow_context *subflow, 628 const struct mptcp_options_received *mp_opt); 629 bool __mptcp_retransmit_pending_data(struct sock *sk); 630 void mptcp_check_and_set_pending(struct sock *sk); 631 void __mptcp_push_pending(struct sock *sk, unsigned int flags); 632 bool mptcp_subflow_data_available(struct sock *sk); 633 void __init mptcp_subflow_init(void); 634 void mptcp_subflow_shutdown(struct sock *sk, struct sock *ssk, int how); 635 void mptcp_close_ssk(struct sock *sk, struct sock *ssk, 636 struct mptcp_subflow_context *subflow); 637 void __mptcp_subflow_send_ack(struct sock *ssk); 638 void mptcp_subflow_reset(struct sock *ssk); 639 void mptcp_subflow_queue_clean(struct sock *sk, struct sock *ssk); 640 void mptcp_sock_graft(struct sock *sk, struct socket *parent); 641 struct sock *__mptcp_nmpc_sk(struct mptcp_sock *msk); 642 bool __mptcp_close(struct sock *sk, long timeout); 643 void mptcp_cancel_work(struct sock *sk); 644 void __mptcp_unaccepted_force_close(struct sock *sk); 645 void mptcp_set_owner_r(struct sk_buff *skb, struct sock *sk); 646 void mptcp_set_state(struct sock *sk, int state); 647 648 bool mptcp_addresses_equal(const struct mptcp_addr_info *a, 649 const struct mptcp_addr_info *b, bool use_port); 650 void mptcp_local_address(const struct sock_common *skc, struct mptcp_addr_info *addr); 651 652 /* called with sk socket lock held */ 653 int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_addr_info *loc, 654 const struct mptcp_addr_info *remote); 655 int mptcp_subflow_create_socket(struct sock *sk, unsigned short family, 656 struct socket **new_sock); 657 void mptcp_info2sockaddr(const struct mptcp_addr_info *info, 658 struct sockaddr_storage *addr, 659 unsigned short family); 660 struct mptcp_sched_ops *mptcp_sched_find(const char *name); 661 int mptcp_register_scheduler(struct mptcp_sched_ops *sched); 662 void mptcp_unregister_scheduler(struct mptcp_sched_ops *sched); 663 void mptcp_sched_init(void); 664 int mptcp_init_sched(struct mptcp_sock *msk, 665 struct mptcp_sched_ops *sched); 666 void mptcp_release_sched(struct mptcp_sock *msk); 667 void mptcp_subflow_set_scheduled(struct mptcp_subflow_context *subflow, 668 bool scheduled); 669 struct sock *mptcp_subflow_get_send(struct mptcp_sock *msk); 670 struct sock *mptcp_subflow_get_retrans(struct mptcp_sock *msk); 671 int mptcp_sched_get_send(struct mptcp_sock *msk); 672 int mptcp_sched_get_retrans(struct mptcp_sock *msk); 673 674 static inline u64 mptcp_data_avail(const struct mptcp_sock *msk) 675 { 676 return READ_ONCE(msk->bytes_received) - READ_ONCE(msk->bytes_consumed); 677 } 678 679 static inline bool mptcp_epollin_ready(const struct sock *sk) 680 { 681 /* mptcp doesn't have to deal with small skbs in the receive queue, 682 * at it can always coalesce them 683 */ 684 return (mptcp_data_avail(mptcp_sk(sk)) >= sk->sk_rcvlowat) || 685 (mem_cgroup_sockets_enabled && sk->sk_memcg && 686 mem_cgroup_under_socket_pressure(sk->sk_memcg)) || 687 READ_ONCE(tcp_memory_pressure); 688 } 689 690 int mptcp_set_rcvlowat(struct sock *sk, int val); 691 692 static inline bool __tcp_can_send(const struct sock *ssk) 693 { 694 /* only send if our side has not closed yet */ 695 return ((1 << inet_sk_state_load(ssk)) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)); 696 } 697 698 static inline bool __mptcp_subflow_active(struct mptcp_subflow_context *subflow) 699 { 700 /* can't send if JOIN hasn't completed yet (i.e. is usable for mptcp) */ 701 if (subflow->request_join && !subflow->fully_established) 702 return false; 703 704 return __tcp_can_send(mptcp_subflow_tcp_sock(subflow)); 705 } 706 707 void mptcp_subflow_set_active(struct mptcp_subflow_context *subflow); 708 709 bool mptcp_subflow_active(struct mptcp_subflow_context *subflow); 710 711 void mptcp_subflow_drop_ctx(struct sock *ssk); 712 713 static inline void mptcp_subflow_tcp_fallback(struct sock *sk, 714 struct mptcp_subflow_context *ctx) 715 { 716 sk->sk_data_ready = sock_def_readable; 717 sk->sk_state_change = ctx->tcp_state_change; 718 sk->sk_write_space = sk_stream_write_space; 719 sk->sk_error_report = ctx->tcp_error_report; 720 721 inet_csk(sk)->icsk_af_ops = ctx->icsk_af_ops; 722 } 723 724 void __init mptcp_proto_init(void); 725 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 726 int __init mptcp_proto_v6_init(void); 727 #endif 728 729 struct sock *mptcp_sk_clone_init(const struct sock *sk, 730 const struct mptcp_options_received *mp_opt, 731 struct sock *ssk, 732 struct request_sock *req); 733 void mptcp_get_options(const struct sk_buff *skb, 734 struct mptcp_options_received *mp_opt); 735 736 void mptcp_finish_connect(struct sock *sk); 737 void __mptcp_sync_state(struct sock *sk, int state); 738 void mptcp_reset_tout_timer(struct mptcp_sock *msk, unsigned long fail_tout); 739 740 static inline void mptcp_stop_tout_timer(struct sock *sk) 741 { 742 if (!inet_csk(sk)->icsk_mtup.probe_timestamp) 743 return; 744 745 sk_stop_timer(sk, &sk->sk_timer); 746 inet_csk(sk)->icsk_mtup.probe_timestamp = 0; 747 } 748 749 static inline void mptcp_set_close_tout(struct sock *sk, unsigned long tout) 750 { 751 /* avoid 0 timestamp, as that means no close timeout */ 752 inet_csk(sk)->icsk_mtup.probe_timestamp = tout ? : 1; 753 } 754 755 static inline void mptcp_start_tout_timer(struct sock *sk) 756 { 757 mptcp_set_close_tout(sk, tcp_jiffies32); 758 mptcp_reset_tout_timer(mptcp_sk(sk), 0); 759 } 760 761 static inline bool mptcp_is_fully_established(struct sock *sk) 762 { 763 return inet_sk_state_load(sk) == TCP_ESTABLISHED && 764 READ_ONCE(mptcp_sk(sk)->fully_established); 765 } 766 767 void mptcp_rcv_space_init(struct mptcp_sock *msk, const struct sock *ssk); 768 void mptcp_data_ready(struct sock *sk, struct sock *ssk); 769 bool mptcp_finish_join(struct sock *sk); 770 bool mptcp_schedule_work(struct sock *sk); 771 int mptcp_setsockopt(struct sock *sk, int level, int optname, 772 sockptr_t optval, unsigned int optlen); 773 int mptcp_getsockopt(struct sock *sk, int level, int optname, 774 char __user *optval, int __user *option); 775 776 u64 __mptcp_expand_seq(u64 old_seq, u64 cur_seq); 777 static inline u64 mptcp_expand_seq(u64 old_seq, u64 cur_seq, bool use_64bit) 778 { 779 if (use_64bit) 780 return cur_seq; 781 782 return __mptcp_expand_seq(old_seq, cur_seq); 783 } 784 void __mptcp_check_push(struct sock *sk, struct sock *ssk); 785 void __mptcp_data_acked(struct sock *sk); 786 void __mptcp_error_report(struct sock *sk); 787 bool mptcp_update_rcv_data_fin(struct mptcp_sock *msk, u64 data_fin_seq, bool use_64bit); 788 static inline bool mptcp_data_fin_enabled(const struct mptcp_sock *msk) 789 { 790 return READ_ONCE(msk->snd_data_fin_enable) && 791 READ_ONCE(msk->write_seq) == READ_ONCE(msk->snd_nxt); 792 } 793 794 static inline void __mptcp_sync_sndbuf(struct sock *sk) 795 { 796 struct mptcp_subflow_context *subflow; 797 int ssk_sndbuf, new_sndbuf; 798 799 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) 800 return; 801 802 new_sndbuf = sock_net(sk)->ipv4.sysctl_tcp_wmem[0]; 803 mptcp_for_each_subflow(mptcp_sk(sk), subflow) { 804 ssk_sndbuf = READ_ONCE(mptcp_subflow_tcp_sock(subflow)->sk_sndbuf); 805 806 subflow->cached_sndbuf = ssk_sndbuf; 807 new_sndbuf += ssk_sndbuf; 808 } 809 810 /* the msk max wmem limit is <nr_subflows> * tcp wmem[2] */ 811 WRITE_ONCE(sk->sk_sndbuf, new_sndbuf); 812 } 813 814 /* The called held both the msk socket and the subflow socket locks, 815 * possibly under BH 816 */ 817 static inline void __mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk) 818 { 819 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 820 821 if (READ_ONCE(ssk->sk_sndbuf) != subflow->cached_sndbuf) 822 __mptcp_sync_sndbuf(sk); 823 } 824 825 /* the caller held only the subflow socket lock, either in process or 826 * BH context. Additionally this can be called under the msk data lock, 827 * so we can't acquire such lock here: let the delegate action acquires 828 * the needed locks in suitable order. 829 */ 830 static inline void mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk) 831 { 832 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 833 834 if (likely(READ_ONCE(ssk->sk_sndbuf) == subflow->cached_sndbuf)) 835 return; 836 837 local_bh_disable(); 838 mptcp_subflow_delegate(subflow, MPTCP_DELEGATE_SNDBUF); 839 local_bh_enable(); 840 } 841 842 static inline void mptcp_write_space(struct sock *sk) 843 { 844 if (sk_stream_is_writeable(sk)) { 845 /* pairs with memory barrier in mptcp_poll */ 846 smp_mb(); 847 if (test_and_clear_bit(MPTCP_NOSPACE, &mptcp_sk(sk)->flags)) 848 sk_stream_write_space(sk); 849 } 850 } 851 852 void mptcp_destroy_common(struct mptcp_sock *msk, unsigned int flags); 853 854 #define MPTCP_TOKEN_MAX_RETRIES 4 855 856 void __init mptcp_token_init(void); 857 static inline void mptcp_token_init_request(struct request_sock *req) 858 { 859 mptcp_subflow_rsk(req)->token_node.pprev = NULL; 860 } 861 862 int mptcp_token_new_request(struct request_sock *req); 863 void mptcp_token_destroy_request(struct request_sock *req); 864 int mptcp_token_new_connect(struct sock *ssk); 865 void mptcp_token_accept(struct mptcp_subflow_request_sock *r, 866 struct mptcp_sock *msk); 867 bool mptcp_token_exists(u32 token); 868 struct mptcp_sock *mptcp_token_get_sock(struct net *net, u32 token); 869 struct mptcp_sock *mptcp_token_iter_next(const struct net *net, long *s_slot, 870 long *s_num); 871 void mptcp_token_destroy(struct mptcp_sock *msk); 872 873 void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn); 874 875 void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u8 *msg, int len, void *hmac); 876 __sum16 __mptcp_make_csum(u64 data_seq, u32 subflow_seq, u16 data_len, __wsum sum); 877 878 void __init mptcp_pm_init(void); 879 void mptcp_pm_data_init(struct mptcp_sock *msk); 880 void mptcp_pm_data_reset(struct mptcp_sock *msk); 881 int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info, 882 struct mptcp_addr_info *addr); 883 int mptcp_pm_parse_entry(struct nlattr *attr, struct genl_info *info, 884 bool require_family, 885 struct mptcp_pm_addr_entry *entry); 886 bool mptcp_pm_addr_families_match(const struct sock *sk, 887 const struct mptcp_addr_info *loc, 888 const struct mptcp_addr_info *rem); 889 void mptcp_pm_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); 890 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); 891 void mptcp_pm_new_connection(struct mptcp_sock *msk, const struct sock *ssk, int server_side); 892 void mptcp_pm_fully_established(struct mptcp_sock *msk, const struct sock *ssk); 893 bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk); 894 void mptcp_pm_connection_closed(struct mptcp_sock *msk); 895 void mptcp_pm_subflow_established(struct mptcp_sock *msk); 896 bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk); 897 void mptcp_pm_subflow_check_next(struct mptcp_sock *msk, 898 const struct mptcp_subflow_context *subflow); 899 void mptcp_pm_add_addr_received(const struct sock *ssk, 900 const struct mptcp_addr_info *addr); 901 void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk, 902 const struct mptcp_addr_info *addr); 903 void mptcp_pm_add_addr_send_ack(struct mptcp_sock *msk); 904 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk); 905 void mptcp_pm_rm_addr_received(struct mptcp_sock *msk, 906 const struct mptcp_rm_list *rm_list); 907 void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup); 908 void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq); 909 int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk, 910 struct mptcp_addr_info *addr, 911 struct mptcp_addr_info *rem, 912 u8 bkup); 913 bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk, 914 const struct mptcp_addr_info *addr); 915 void mptcp_pm_free_anno_list(struct mptcp_sock *msk); 916 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk); 917 struct mptcp_pm_add_entry * 918 mptcp_pm_del_add_timer(struct mptcp_sock *msk, 919 const struct mptcp_addr_info *addr, bool check_id); 920 struct mptcp_pm_add_entry * 921 mptcp_lookup_anno_list_by_saddr(const struct mptcp_sock *msk, 922 const struct mptcp_addr_info *addr); 923 int mptcp_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, 924 unsigned int id, 925 u8 *flags, int *ifindex); 926 int mptcp_pm_nl_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, unsigned int id, 927 u8 *flags, int *ifindex); 928 int mptcp_userspace_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, 929 unsigned int id, 930 u8 *flags, int *ifindex); 931 int mptcp_pm_set_flags(struct net *net, struct nlattr *token, 932 struct mptcp_pm_addr_entry *loc, 933 struct mptcp_pm_addr_entry *rem, u8 bkup); 934 int mptcp_pm_nl_set_flags(struct net *net, struct mptcp_pm_addr_entry *addr, u8 bkup); 935 int mptcp_userspace_pm_set_flags(struct net *net, struct nlattr *token, 936 struct mptcp_pm_addr_entry *loc, 937 struct mptcp_pm_addr_entry *rem, u8 bkup); 938 int mptcp_pm_announce_addr(struct mptcp_sock *msk, 939 const struct mptcp_addr_info *addr, 940 bool echo); 941 int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); 942 int mptcp_pm_remove_subflow(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); 943 void mptcp_pm_remove_addrs(struct mptcp_sock *msk, struct list_head *rm_list); 944 void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk, 945 struct list_head *rm_list); 946 947 void mptcp_free_local_addr_list(struct mptcp_sock *msk); 948 949 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk, 950 const struct sock *ssk, gfp_t gfp); 951 void mptcp_event_addr_announced(const struct sock *ssk, const struct mptcp_addr_info *info); 952 void mptcp_event_addr_removed(const struct mptcp_sock *msk, u8 id); 953 void mptcp_event_pm_listener(const struct sock *ssk, 954 enum mptcp_event_type event); 955 bool mptcp_userspace_pm_active(const struct mptcp_sock *msk); 956 957 void mptcp_fastopen_gen_msk_ackseq(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow, 958 const struct mptcp_options_received *mp_opt); 959 void mptcp_fastopen_subflow_synack_set_params(struct mptcp_subflow_context *subflow, 960 struct request_sock *req); 961 962 static inline bool mptcp_pm_should_add_signal(struct mptcp_sock *msk) 963 { 964 return READ_ONCE(msk->pm.addr_signal) & 965 (BIT(MPTCP_ADD_ADDR_SIGNAL) | BIT(MPTCP_ADD_ADDR_ECHO)); 966 } 967 968 static inline bool mptcp_pm_should_add_signal_addr(struct mptcp_sock *msk) 969 { 970 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_SIGNAL); 971 } 972 973 static inline bool mptcp_pm_should_add_signal_echo(struct mptcp_sock *msk) 974 { 975 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_ECHO); 976 } 977 978 static inline bool mptcp_pm_should_rm_signal(struct mptcp_sock *msk) 979 { 980 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_RM_ADDR_SIGNAL); 981 } 982 983 static inline bool mptcp_pm_is_userspace(const struct mptcp_sock *msk) 984 { 985 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_USERSPACE; 986 } 987 988 static inline bool mptcp_pm_is_kernel(const struct mptcp_sock *msk) 989 { 990 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_KERNEL; 991 } 992 993 static inline unsigned int mptcp_add_addr_len(int family, bool echo, bool port) 994 { 995 u8 len = TCPOLEN_MPTCP_ADD_ADDR_BASE; 996 997 if (family == AF_INET6) 998 len = TCPOLEN_MPTCP_ADD_ADDR6_BASE; 999 if (!echo) 1000 len += MPTCPOPT_THMAC_LEN; 1001 /* account for 2 trailing 'nop' options */ 1002 if (port) 1003 len += TCPOLEN_MPTCP_PORT_LEN + TCPOLEN_MPTCP_PORT_ALIGN; 1004 1005 return len; 1006 } 1007 1008 static inline int mptcp_rm_addr_len(const struct mptcp_rm_list *rm_list) 1009 { 1010 if (rm_list->nr == 0 || rm_list->nr > MPTCP_RM_IDS_MAX) 1011 return -EINVAL; 1012 1013 return TCPOLEN_MPTCP_RM_ADDR_BASE + roundup(rm_list->nr - 1, 4) + 1; 1014 } 1015 1016 bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, const struct sk_buff *skb, 1017 unsigned int opt_size, unsigned int remaining, 1018 struct mptcp_addr_info *addr, bool *echo, 1019 bool *drop_other_suboptions); 1020 bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining, 1021 struct mptcp_rm_list *rm_list); 1022 int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc); 1023 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc); 1024 int mptcp_userspace_pm_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc); 1025 1026 void __init mptcp_pm_nl_init(void); 1027 void mptcp_pm_nl_work(struct mptcp_sock *msk); 1028 void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk, 1029 const struct mptcp_rm_list *rm_list); 1030 unsigned int mptcp_pm_get_add_addr_signal_max(const struct mptcp_sock *msk); 1031 unsigned int mptcp_pm_get_add_addr_accept_max(const struct mptcp_sock *msk); 1032 unsigned int mptcp_pm_get_subflows_max(const struct mptcp_sock *msk); 1033 unsigned int mptcp_pm_get_local_addr_max(const struct mptcp_sock *msk); 1034 1035 /* called under PM lock */ 1036 static inline void __mptcp_pm_close_subflow(struct mptcp_sock *msk) 1037 { 1038 if (--msk->pm.subflows < mptcp_pm_get_subflows_max(msk)) 1039 WRITE_ONCE(msk->pm.accept_subflow, true); 1040 } 1041 1042 static inline void mptcp_pm_close_subflow(struct mptcp_sock *msk) 1043 { 1044 spin_lock_bh(&msk->pm.lock); 1045 __mptcp_pm_close_subflow(msk); 1046 spin_unlock_bh(&msk->pm.lock); 1047 } 1048 1049 void mptcp_sockopt_sync(struct mptcp_sock *msk, struct sock *ssk); 1050 void mptcp_sockopt_sync_locked(struct mptcp_sock *msk, struct sock *ssk); 1051 1052 static inline struct mptcp_ext *mptcp_get_ext(const struct sk_buff *skb) 1053 { 1054 return (struct mptcp_ext *)skb_ext_find(skb, SKB_EXT_MPTCP); 1055 } 1056 1057 void mptcp_diag_subflow_init(struct tcp_ulp_ops *ops); 1058 1059 static inline bool __mptcp_check_fallback(const struct mptcp_sock *msk) 1060 { 1061 return test_bit(MPTCP_FALLBACK_DONE, &msk->flags); 1062 } 1063 1064 static inline bool mptcp_check_fallback(const struct sock *sk) 1065 { 1066 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 1067 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 1068 1069 return __mptcp_check_fallback(msk); 1070 } 1071 1072 static inline void __mptcp_do_fallback(struct mptcp_sock *msk) 1073 { 1074 if (__mptcp_check_fallback(msk)) { 1075 pr_debug("TCP fallback already done (msk=%p)", msk); 1076 return; 1077 } 1078 set_bit(MPTCP_FALLBACK_DONE, &msk->flags); 1079 } 1080 1081 static inline bool __mptcp_has_initial_subflow(const struct mptcp_sock *msk) 1082 { 1083 struct sock *ssk = READ_ONCE(msk->first); 1084 1085 return ssk && ((1 << inet_sk_state_load(ssk)) & 1086 (TCPF_ESTABLISHED | TCPF_SYN_SENT | 1087 TCPF_SYN_RECV | TCPF_LISTEN)); 1088 } 1089 1090 static inline void mptcp_do_fallback(struct sock *ssk) 1091 { 1092 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 1093 struct sock *sk = subflow->conn; 1094 struct mptcp_sock *msk; 1095 1096 msk = mptcp_sk(sk); 1097 __mptcp_do_fallback(msk); 1098 if (READ_ONCE(msk->snd_data_fin_enable) && !(ssk->sk_shutdown & SEND_SHUTDOWN)) { 1099 gfp_t saved_allocation = ssk->sk_allocation; 1100 1101 /* we are in a atomic (BH) scope, override ssk default for data 1102 * fin allocation 1103 */ 1104 ssk->sk_allocation = GFP_ATOMIC; 1105 ssk->sk_shutdown |= SEND_SHUTDOWN; 1106 tcp_shutdown(ssk, SEND_SHUTDOWN); 1107 ssk->sk_allocation = saved_allocation; 1108 } 1109 } 1110 1111 #define pr_fallback(a) pr_debug("%s:fallback to TCP (msk=%p)", __func__, a) 1112 1113 static inline bool mptcp_check_infinite_map(struct sk_buff *skb) 1114 { 1115 struct mptcp_ext *mpext; 1116 1117 mpext = skb ? mptcp_get_ext(skb) : NULL; 1118 if (mpext && mpext->infinite_map) 1119 return true; 1120 1121 return false; 1122 } 1123 1124 static inline bool is_active_ssk(struct mptcp_subflow_context *subflow) 1125 { 1126 return (subflow->request_mptcp || subflow->request_join); 1127 } 1128 1129 static inline bool subflow_simultaneous_connect(struct sock *sk) 1130 { 1131 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 1132 1133 return (1 << sk->sk_state) & (TCPF_ESTABLISHED | TCPF_FIN_WAIT1) && 1134 is_active_ssk(subflow) && 1135 !subflow->conn_finished; 1136 } 1137 1138 #ifdef CONFIG_SYN_COOKIES 1139 void subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 1140 struct sk_buff *skb); 1141 bool mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 1142 struct sk_buff *skb); 1143 void __init mptcp_join_cookie_init(void); 1144 #else 1145 static inline void 1146 subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 1147 struct sk_buff *skb) {} 1148 static inline bool 1149 mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 1150 struct sk_buff *skb) 1151 { 1152 return false; 1153 } 1154 1155 static inline void mptcp_join_cookie_init(void) {} 1156 #endif 1157 1158 #endif /* __MPTCP_PROTOCOL_H */ 1159