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; 264 u64 remote_key; 265 u64 write_seq; 266 u64 bytes_sent; 267 u64 snd_nxt; 268 u64 bytes_received; 269 u64 ack_seq; 270 atomic64_t rcv_wnd_sent; 271 u64 rcv_data_fin_seq; 272 u64 bytes_retrans; 273 u64 bytes_consumed; 274 int rmem_fwd_alloc; 275 int snd_burst; 276 int old_wspace; 277 u64 recovery_snd_nxt; /* in recovery mode accept up to this seq; 278 * recovery related fields are under data_lock 279 * protection 280 */ 281 u64 bytes_acked; 282 u64 snd_una; 283 u64 wnd_end; 284 unsigned long timer_ival; 285 u32 token; 286 int rmem_released; 287 unsigned long flags; 288 unsigned long cb_flags; 289 bool recovery; /* closing subflow write queue reinjected */ 290 bool can_ack; 291 bool fully_established; 292 bool rcv_data_fin; 293 bool snd_data_fin_enable; 294 bool rcv_fastclose; 295 bool use_64bit_ack; /* Set when we received a 64-bit DSN */ 296 bool csum_enabled; 297 bool allow_infinite_fallback; 298 u8 pending_state; /* A subflow asked to set this sk_state, 299 * protected by the msk data lock 300 */ 301 u8 mpc_endpoint_id; 302 u8 recvmsg_inq:1, 303 cork:1, 304 nodelay:1, 305 fastopening:1, 306 in_accept_queue:1, 307 free_first:1, 308 rcvspace_init:1; 309 struct work_struct work; 310 struct sk_buff *ooo_last_skb; 311 struct rb_root out_of_order_queue; 312 struct sk_buff_head receive_queue; 313 struct list_head conn_list; 314 struct list_head rtx_queue; 315 struct mptcp_data_frag *first_pending; 316 struct list_head join_list; 317 struct sock *first; /* The mptcp ops can safely dereference, using suitable 318 * ONCE annotation, the subflow outside the socket 319 * lock as such sock is freed after close(). 320 */ 321 struct mptcp_pm_data pm; 322 struct mptcp_sched_ops *sched; 323 struct { 324 u32 space; /* bytes copied in last measurement window */ 325 u32 copied; /* bytes copied in this measurement window */ 326 u64 time; /* start time of measurement window */ 327 u64 rtt_us; /* last maximum rtt of subflows */ 328 } rcvq_space; 329 u8 scaling_ratio; 330 331 u32 subflow_id; 332 u32 setsockopt_seq; 333 char ca_name[TCP_CA_NAME_MAX]; 334 }; 335 336 #define mptcp_data_lock(sk) spin_lock_bh(&(sk)->sk_lock.slock) 337 #define mptcp_data_unlock(sk) spin_unlock_bh(&(sk)->sk_lock.slock) 338 339 #define mptcp_for_each_subflow(__msk, __subflow) \ 340 list_for_each_entry(__subflow, &((__msk)->conn_list), node) 341 #define mptcp_for_each_subflow_safe(__msk, __subflow, __tmp) \ 342 list_for_each_entry_safe(__subflow, __tmp, &((__msk)->conn_list), node) 343 344 static inline void msk_owned_by_me(const struct mptcp_sock *msk) 345 { 346 sock_owned_by_me((const struct sock *)msk); 347 } 348 349 #define mptcp_sk(ptr) container_of_const(ptr, struct mptcp_sock, sk.icsk_inet.sk) 350 351 /* the msk socket don't use the backlog, also account for the bulk 352 * free memory 353 */ 354 static inline int __mptcp_rmem(const struct sock *sk) 355 { 356 return atomic_read(&sk->sk_rmem_alloc) - READ_ONCE(mptcp_sk(sk)->rmem_released); 357 } 358 359 static inline int mptcp_win_from_space(const struct sock *sk, int space) 360 { 361 return __tcp_win_from_space(mptcp_sk(sk)->scaling_ratio, space); 362 } 363 364 static inline int __mptcp_space(const struct sock *sk) 365 { 366 return mptcp_win_from_space(sk, READ_ONCE(sk->sk_rcvbuf) - __mptcp_rmem(sk)); 367 } 368 369 static inline struct mptcp_data_frag *mptcp_send_head(const struct sock *sk) 370 { 371 const struct mptcp_sock *msk = mptcp_sk(sk); 372 373 return READ_ONCE(msk->first_pending); 374 } 375 376 static inline struct mptcp_data_frag *mptcp_send_next(struct sock *sk) 377 { 378 struct mptcp_sock *msk = mptcp_sk(sk); 379 struct mptcp_data_frag *cur; 380 381 cur = msk->first_pending; 382 return list_is_last(&cur->list, &msk->rtx_queue) ? NULL : 383 list_next_entry(cur, list); 384 } 385 386 static inline struct mptcp_data_frag *mptcp_pending_tail(const struct sock *sk) 387 { 388 const struct mptcp_sock *msk = mptcp_sk(sk); 389 390 if (!msk->first_pending) 391 return NULL; 392 393 if (WARN_ON_ONCE(list_empty(&msk->rtx_queue))) 394 return NULL; 395 396 return list_last_entry(&msk->rtx_queue, struct mptcp_data_frag, list); 397 } 398 399 static inline struct mptcp_data_frag *mptcp_rtx_head(struct sock *sk) 400 { 401 struct mptcp_sock *msk = mptcp_sk(sk); 402 403 if (msk->snd_una == READ_ONCE(msk->snd_nxt)) 404 return NULL; 405 406 return list_first_entry_or_null(&msk->rtx_queue, struct mptcp_data_frag, list); 407 } 408 409 struct csum_pseudo_header { 410 __be64 data_seq; 411 __be32 subflow_seq; 412 __be16 data_len; 413 __sum16 csum; 414 }; 415 416 struct mptcp_subflow_request_sock { 417 struct tcp_request_sock sk; 418 u16 mp_capable : 1, 419 mp_join : 1, 420 backup : 1, 421 csum_reqd : 1, 422 allow_join_id0 : 1; 423 u8 local_id; 424 u8 remote_id; 425 u64 local_key; 426 u64 idsn; 427 u32 token; 428 u32 ssn_offset; 429 u64 thmac; 430 u32 local_nonce; 431 u32 remote_nonce; 432 struct mptcp_sock *msk; 433 struct hlist_nulls_node token_node; 434 }; 435 436 static inline struct mptcp_subflow_request_sock * 437 mptcp_subflow_rsk(const struct request_sock *rsk) 438 { 439 return (struct mptcp_subflow_request_sock *)rsk; 440 } 441 442 struct mptcp_delegated_action { 443 struct napi_struct napi; 444 struct list_head head; 445 }; 446 447 DECLARE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions); 448 449 #define MPTCP_DELEGATE_SCHEDULED 0 450 #define MPTCP_DELEGATE_SEND 1 451 #define MPTCP_DELEGATE_ACK 2 452 #define MPTCP_DELEGATE_SNDBUF 3 453 454 #define MPTCP_DELEGATE_ACTIONS_MASK (~BIT(MPTCP_DELEGATE_SCHEDULED)) 455 /* MPTCP subflow context */ 456 struct mptcp_subflow_context { 457 struct list_head node;/* conn_list of subflows */ 458 459 struct_group(reset, 460 461 unsigned long avg_pacing_rate; /* protected by msk socket lock */ 462 u64 local_key; 463 u64 remote_key; 464 u64 idsn; 465 u64 map_seq; 466 u32 snd_isn; 467 u32 token; 468 u32 rel_write_seq; 469 u32 map_subflow_seq; 470 u32 ssn_offset; 471 u32 map_data_len; 472 __wsum map_data_csum; 473 u32 map_csum_len; 474 u32 request_mptcp : 1, /* send MP_CAPABLE */ 475 request_join : 1, /* send MP_JOIN */ 476 request_bkup : 1, 477 mp_capable : 1, /* remote is MPTCP capable */ 478 mp_join : 1, /* remote is JOINing */ 479 fully_established : 1, /* path validated */ 480 pm_notified : 1, /* PM hook called for established status */ 481 conn_finished : 1, 482 map_valid : 1, 483 map_csum_reqd : 1, 484 map_data_fin : 1, 485 mpc_map : 1, 486 backup : 1, 487 send_mp_prio : 1, 488 send_mp_fail : 1, 489 send_fastclose : 1, 490 send_infinite_map : 1, 491 remote_key_valid : 1, /* received the peer key from */ 492 disposable : 1, /* ctx can be free at ulp release time */ 493 stale : 1, /* unable to snd/rcv data, do not use for xmit */ 494 local_id_valid : 1, /* local_id is correctly initialized */ 495 valid_csum_seen : 1, /* at least one csum validated */ 496 is_mptfo : 1, /* subflow is doing TFO */ 497 __unused : 9; 498 bool data_avail; 499 bool scheduled; 500 u32 remote_nonce; 501 u64 thmac; 502 u32 local_nonce; 503 u32 remote_token; 504 union { 505 u8 hmac[MPTCPOPT_HMAC_LEN]; /* MPJ subflow only */ 506 u64 iasn; /* initial ack sequence number, MPC subflows only */ 507 }; 508 u8 local_id; 509 u8 remote_id; 510 u8 reset_seen:1; 511 u8 reset_transient:1; 512 u8 reset_reason:4; 513 u8 stale_count; 514 515 u32 subflow_id; 516 517 long delegated_status; 518 unsigned long fail_tout; 519 520 ); 521 522 struct list_head delegated_node; /* link into delegated_action, protected by local BH */ 523 524 u32 setsockopt_seq; 525 u32 stale_rcv_tstamp; 526 int cached_sndbuf; /* sndbuf size when last synced with the msk sndbuf, 527 * protected by the msk socket lock 528 */ 529 530 struct sock *tcp_sock; /* tcp sk backpointer */ 531 struct sock *conn; /* parent mptcp_sock */ 532 const struct inet_connection_sock_af_ops *icsk_af_ops; 533 void (*tcp_state_change)(struct sock *sk); 534 void (*tcp_error_report)(struct sock *sk); 535 536 struct rcu_head rcu; 537 }; 538 539 static inline struct mptcp_subflow_context * 540 mptcp_subflow_ctx(const struct sock *sk) 541 { 542 struct inet_connection_sock *icsk = inet_csk(sk); 543 544 /* Use RCU on icsk_ulp_data only for sock diag code */ 545 return (__force struct mptcp_subflow_context *)icsk->icsk_ulp_data; 546 } 547 548 static inline struct sock * 549 mptcp_subflow_tcp_sock(const struct mptcp_subflow_context *subflow) 550 { 551 return subflow->tcp_sock; 552 } 553 554 static inline void 555 mptcp_subflow_ctx_reset(struct mptcp_subflow_context *subflow) 556 { 557 memset(&subflow->reset, 0, sizeof(subflow->reset)); 558 subflow->request_mptcp = 1; 559 } 560 561 static inline u64 562 mptcp_subflow_get_map_offset(const struct mptcp_subflow_context *subflow) 563 { 564 return tcp_sk(mptcp_subflow_tcp_sock(subflow))->copied_seq - 565 subflow->ssn_offset - 566 subflow->map_subflow_seq; 567 } 568 569 static inline u64 570 mptcp_subflow_get_mapped_dsn(const struct mptcp_subflow_context *subflow) 571 { 572 return subflow->map_seq + mptcp_subflow_get_map_offset(subflow); 573 } 574 575 void mptcp_subflow_process_delegated(struct sock *ssk, long actions); 576 577 static inline void mptcp_subflow_delegate(struct mptcp_subflow_context *subflow, int action) 578 { 579 long old, set_bits = BIT(MPTCP_DELEGATE_SCHEDULED) | BIT(action); 580 struct mptcp_delegated_action *delegated; 581 bool schedule; 582 583 /* the caller held the subflow bh socket lock */ 584 lockdep_assert_in_softirq(); 585 586 /* The implied barrier pairs with tcp_release_cb_override() 587 * mptcp_napi_poll(), and ensures the below list check sees list 588 * updates done prior to delegated status bits changes 589 */ 590 old = set_mask_bits(&subflow->delegated_status, 0, set_bits); 591 if (!(old & BIT(MPTCP_DELEGATE_SCHEDULED))) { 592 if (WARN_ON_ONCE(!list_empty(&subflow->delegated_node))) 593 return; 594 595 delegated = this_cpu_ptr(&mptcp_delegated_actions); 596 schedule = list_empty(&delegated->head); 597 list_add_tail(&subflow->delegated_node, &delegated->head); 598 sock_hold(mptcp_subflow_tcp_sock(subflow)); 599 if (schedule) 600 napi_schedule(&delegated->napi); 601 } 602 } 603 604 static inline struct mptcp_subflow_context * 605 mptcp_subflow_delegated_next(struct mptcp_delegated_action *delegated) 606 { 607 struct mptcp_subflow_context *ret; 608 609 if (list_empty(&delegated->head)) 610 return NULL; 611 612 ret = list_first_entry(&delegated->head, struct mptcp_subflow_context, delegated_node); 613 list_del_init(&ret->delegated_node); 614 return ret; 615 } 616 617 int mptcp_is_enabled(const struct net *net); 618 unsigned int mptcp_get_add_addr_timeout(const struct net *net); 619 int mptcp_is_checksum_enabled(const struct net *net); 620 int mptcp_allow_join_id0(const struct net *net); 621 unsigned int mptcp_stale_loss_cnt(const struct net *net); 622 unsigned int mptcp_close_timeout(const struct sock *sk); 623 int mptcp_get_pm_type(const struct net *net); 624 const char *mptcp_get_scheduler(const struct net *net); 625 void __mptcp_subflow_fully_established(struct mptcp_sock *msk, 626 struct mptcp_subflow_context *subflow, 627 const struct mptcp_options_received *mp_opt); 628 bool __mptcp_retransmit_pending_data(struct sock *sk); 629 void mptcp_check_and_set_pending(struct sock *sk); 630 void __mptcp_push_pending(struct sock *sk, unsigned int flags); 631 bool mptcp_subflow_data_available(struct sock *sk); 632 void __init mptcp_subflow_init(void); 633 void mptcp_subflow_shutdown(struct sock *sk, struct sock *ssk, int how); 634 void mptcp_close_ssk(struct sock *sk, struct sock *ssk, 635 struct mptcp_subflow_context *subflow); 636 void __mptcp_subflow_send_ack(struct sock *ssk); 637 void mptcp_subflow_reset(struct sock *ssk); 638 void mptcp_subflow_queue_clean(struct sock *sk, struct sock *ssk); 639 void mptcp_sock_graft(struct sock *sk, struct socket *parent); 640 struct sock *__mptcp_nmpc_sk(struct mptcp_sock *msk); 641 bool __mptcp_close(struct sock *sk, long timeout); 642 void mptcp_cancel_work(struct sock *sk); 643 void __mptcp_unaccepted_force_close(struct sock *sk); 644 void mptcp_set_owner_r(struct sk_buff *skb, struct sock *sk); 645 void mptcp_set_state(struct sock *sk, int state); 646 647 bool mptcp_addresses_equal(const struct mptcp_addr_info *a, 648 const struct mptcp_addr_info *b, bool use_port); 649 void mptcp_local_address(const struct sock_common *skc, struct mptcp_addr_info *addr); 650 651 /* called with sk socket lock held */ 652 int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_addr_info *loc, 653 const struct mptcp_addr_info *remote); 654 int mptcp_subflow_create_socket(struct sock *sk, unsigned short family, 655 struct socket **new_sock); 656 void mptcp_info2sockaddr(const struct mptcp_addr_info *info, 657 struct sockaddr_storage *addr, 658 unsigned short family); 659 struct mptcp_sched_ops *mptcp_sched_find(const char *name); 660 int mptcp_register_scheduler(struct mptcp_sched_ops *sched); 661 void mptcp_unregister_scheduler(struct mptcp_sched_ops *sched); 662 void mptcp_sched_init(void); 663 int mptcp_init_sched(struct mptcp_sock *msk, 664 struct mptcp_sched_ops *sched); 665 void mptcp_release_sched(struct mptcp_sock *msk); 666 void mptcp_subflow_set_scheduled(struct mptcp_subflow_context *subflow, 667 bool scheduled); 668 struct sock *mptcp_subflow_get_send(struct mptcp_sock *msk); 669 struct sock *mptcp_subflow_get_retrans(struct mptcp_sock *msk); 670 int mptcp_sched_get_send(struct mptcp_sock *msk); 671 int mptcp_sched_get_retrans(struct mptcp_sock *msk); 672 673 static inline u64 mptcp_data_avail(const struct mptcp_sock *msk) 674 { 675 return READ_ONCE(msk->bytes_received) - READ_ONCE(msk->bytes_consumed); 676 } 677 678 static inline bool mptcp_epollin_ready(const struct sock *sk) 679 { 680 /* mptcp doesn't have to deal with small skbs in the receive queue, 681 * at it can always coalesce them 682 */ 683 return (mptcp_data_avail(mptcp_sk(sk)) >= sk->sk_rcvlowat) || 684 (mem_cgroup_sockets_enabled && sk->sk_memcg && 685 mem_cgroup_under_socket_pressure(sk->sk_memcg)) || 686 READ_ONCE(tcp_memory_pressure); 687 } 688 689 int mptcp_set_rcvlowat(struct sock *sk, int val); 690 691 static inline bool __tcp_can_send(const struct sock *ssk) 692 { 693 /* only send if our side has not closed yet */ 694 return ((1 << inet_sk_state_load(ssk)) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)); 695 } 696 697 static inline bool __mptcp_subflow_active(struct mptcp_subflow_context *subflow) 698 { 699 /* can't send if JOIN hasn't completed yet (i.e. is usable for mptcp) */ 700 if (subflow->request_join && !subflow->fully_established) 701 return false; 702 703 return __tcp_can_send(mptcp_subflow_tcp_sock(subflow)); 704 } 705 706 void mptcp_subflow_set_active(struct mptcp_subflow_context *subflow); 707 708 bool mptcp_subflow_active(struct mptcp_subflow_context *subflow); 709 710 void mptcp_subflow_drop_ctx(struct sock *ssk); 711 712 static inline void mptcp_subflow_tcp_fallback(struct sock *sk, 713 struct mptcp_subflow_context *ctx) 714 { 715 sk->sk_data_ready = sock_def_readable; 716 sk->sk_state_change = ctx->tcp_state_change; 717 sk->sk_write_space = sk_stream_write_space; 718 sk->sk_error_report = ctx->tcp_error_report; 719 720 inet_csk(sk)->icsk_af_ops = ctx->icsk_af_ops; 721 } 722 723 void __init mptcp_proto_init(void); 724 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 725 int __init mptcp_proto_v6_init(void); 726 #endif 727 728 struct sock *mptcp_sk_clone_init(const struct sock *sk, 729 const struct mptcp_options_received *mp_opt, 730 struct sock *ssk, 731 struct request_sock *req); 732 void mptcp_get_options(const struct sk_buff *skb, 733 struct mptcp_options_received *mp_opt); 734 735 void mptcp_finish_connect(struct sock *sk); 736 void __mptcp_sync_state(struct sock *sk, int state); 737 void mptcp_reset_tout_timer(struct mptcp_sock *msk, unsigned long fail_tout); 738 739 static inline void mptcp_stop_tout_timer(struct sock *sk) 740 { 741 if (!inet_csk(sk)->icsk_mtup.probe_timestamp) 742 return; 743 744 sk_stop_timer(sk, &sk->sk_timer); 745 inet_csk(sk)->icsk_mtup.probe_timestamp = 0; 746 } 747 748 static inline void mptcp_set_close_tout(struct sock *sk, unsigned long tout) 749 { 750 /* avoid 0 timestamp, as that means no close timeout */ 751 inet_csk(sk)->icsk_mtup.probe_timestamp = tout ? : 1; 752 } 753 754 static inline void mptcp_start_tout_timer(struct sock *sk) 755 { 756 mptcp_set_close_tout(sk, tcp_jiffies32); 757 mptcp_reset_tout_timer(mptcp_sk(sk), 0); 758 } 759 760 static inline bool mptcp_is_fully_established(struct sock *sk) 761 { 762 return inet_sk_state_load(sk) == TCP_ESTABLISHED && 763 READ_ONCE(mptcp_sk(sk)->fully_established); 764 } 765 766 void mptcp_rcv_space_init(struct mptcp_sock *msk, const struct sock *ssk); 767 void mptcp_data_ready(struct sock *sk, struct sock *ssk); 768 bool mptcp_finish_join(struct sock *sk); 769 bool mptcp_schedule_work(struct sock *sk); 770 int mptcp_setsockopt(struct sock *sk, int level, int optname, 771 sockptr_t optval, unsigned int optlen); 772 int mptcp_getsockopt(struct sock *sk, int level, int optname, 773 char __user *optval, int __user *option); 774 775 u64 __mptcp_expand_seq(u64 old_seq, u64 cur_seq); 776 static inline u64 mptcp_expand_seq(u64 old_seq, u64 cur_seq, bool use_64bit) 777 { 778 if (use_64bit) 779 return cur_seq; 780 781 return __mptcp_expand_seq(old_seq, cur_seq); 782 } 783 void __mptcp_check_push(struct sock *sk, struct sock *ssk); 784 void __mptcp_data_acked(struct sock *sk); 785 void __mptcp_error_report(struct sock *sk); 786 bool mptcp_update_rcv_data_fin(struct mptcp_sock *msk, u64 data_fin_seq, bool use_64bit); 787 static inline bool mptcp_data_fin_enabled(const struct mptcp_sock *msk) 788 { 789 return READ_ONCE(msk->snd_data_fin_enable) && 790 READ_ONCE(msk->write_seq) == READ_ONCE(msk->snd_nxt); 791 } 792 793 static inline void __mptcp_sync_sndbuf(struct sock *sk) 794 { 795 struct mptcp_subflow_context *subflow; 796 int ssk_sndbuf, new_sndbuf; 797 798 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) 799 return; 800 801 new_sndbuf = sock_net(sk)->ipv4.sysctl_tcp_wmem[0]; 802 mptcp_for_each_subflow(mptcp_sk(sk), subflow) { 803 ssk_sndbuf = READ_ONCE(mptcp_subflow_tcp_sock(subflow)->sk_sndbuf); 804 805 subflow->cached_sndbuf = ssk_sndbuf; 806 new_sndbuf += ssk_sndbuf; 807 } 808 809 /* the msk max wmem limit is <nr_subflows> * tcp wmem[2] */ 810 WRITE_ONCE(sk->sk_sndbuf, new_sndbuf); 811 } 812 813 /* The called held both the msk socket and the subflow socket locks, 814 * possibly under BH 815 */ 816 static inline void __mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk) 817 { 818 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 819 820 if (READ_ONCE(ssk->sk_sndbuf) != subflow->cached_sndbuf) 821 __mptcp_sync_sndbuf(sk); 822 } 823 824 /* the caller held only the subflow socket lock, either in process or 825 * BH context. Additionally this can be called under the msk data lock, 826 * so we can't acquire such lock here: let the delegate action acquires 827 * the needed locks in suitable order. 828 */ 829 static inline void mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk) 830 { 831 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 832 833 if (likely(READ_ONCE(ssk->sk_sndbuf) == subflow->cached_sndbuf)) 834 return; 835 836 local_bh_disable(); 837 mptcp_subflow_delegate(subflow, MPTCP_DELEGATE_SNDBUF); 838 local_bh_enable(); 839 } 840 841 static inline void mptcp_write_space(struct sock *sk) 842 { 843 if (sk_stream_is_writeable(sk)) { 844 /* pairs with memory barrier in mptcp_poll */ 845 smp_mb(); 846 if (test_and_clear_bit(MPTCP_NOSPACE, &mptcp_sk(sk)->flags)) 847 sk_stream_write_space(sk); 848 } 849 } 850 851 void mptcp_destroy_common(struct mptcp_sock *msk, unsigned int flags); 852 853 #define MPTCP_TOKEN_MAX_RETRIES 4 854 855 void __init mptcp_token_init(void); 856 static inline void mptcp_token_init_request(struct request_sock *req) 857 { 858 mptcp_subflow_rsk(req)->token_node.pprev = NULL; 859 } 860 861 int mptcp_token_new_request(struct request_sock *req); 862 void mptcp_token_destroy_request(struct request_sock *req); 863 int mptcp_token_new_connect(struct sock *ssk); 864 void mptcp_token_accept(struct mptcp_subflow_request_sock *r, 865 struct mptcp_sock *msk); 866 bool mptcp_token_exists(u32 token); 867 struct mptcp_sock *mptcp_token_get_sock(struct net *net, u32 token); 868 struct mptcp_sock *mptcp_token_iter_next(const struct net *net, long *s_slot, 869 long *s_num); 870 void mptcp_token_destroy(struct mptcp_sock *msk); 871 872 void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn); 873 874 void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u8 *msg, int len, void *hmac); 875 __sum16 __mptcp_make_csum(u64 data_seq, u32 subflow_seq, u16 data_len, __wsum sum); 876 877 void __init mptcp_pm_init(void); 878 void mptcp_pm_data_init(struct mptcp_sock *msk); 879 void mptcp_pm_data_reset(struct mptcp_sock *msk); 880 int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info, 881 struct mptcp_addr_info *addr); 882 int mptcp_pm_parse_entry(struct nlattr *attr, struct genl_info *info, 883 bool require_family, 884 struct mptcp_pm_addr_entry *entry); 885 bool mptcp_pm_addr_families_match(const struct sock *sk, 886 const struct mptcp_addr_info *loc, 887 const struct mptcp_addr_info *rem); 888 void mptcp_pm_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); 889 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); 890 void mptcp_pm_new_connection(struct mptcp_sock *msk, const struct sock *ssk, int server_side); 891 void mptcp_pm_fully_established(struct mptcp_sock *msk, const struct sock *ssk); 892 bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk); 893 void mptcp_pm_connection_closed(struct mptcp_sock *msk); 894 void mptcp_pm_subflow_established(struct mptcp_sock *msk); 895 bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk); 896 void mptcp_pm_subflow_check_next(struct mptcp_sock *msk, 897 const struct mptcp_subflow_context *subflow); 898 void mptcp_pm_add_addr_received(const struct sock *ssk, 899 const struct mptcp_addr_info *addr); 900 void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk, 901 const struct mptcp_addr_info *addr); 902 void mptcp_pm_add_addr_send_ack(struct mptcp_sock *msk); 903 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk); 904 void mptcp_pm_rm_addr_received(struct mptcp_sock *msk, 905 const struct mptcp_rm_list *rm_list); 906 void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup); 907 void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq); 908 int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk, 909 struct mptcp_addr_info *addr, 910 struct mptcp_addr_info *rem, 911 u8 bkup); 912 bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk, 913 const struct mptcp_addr_info *addr); 914 void mptcp_pm_free_anno_list(struct mptcp_sock *msk); 915 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk); 916 struct mptcp_pm_add_entry * 917 mptcp_pm_del_add_timer(struct mptcp_sock *msk, 918 const struct mptcp_addr_info *addr, bool check_id); 919 struct mptcp_pm_add_entry * 920 mptcp_lookup_anno_list_by_saddr(const struct mptcp_sock *msk, 921 const struct mptcp_addr_info *addr); 922 int mptcp_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, 923 unsigned int id, 924 u8 *flags, int *ifindex); 925 int mptcp_pm_nl_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, unsigned int id, 926 u8 *flags, int *ifindex); 927 int mptcp_userspace_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, 928 unsigned int id, 929 u8 *flags, int *ifindex); 930 int mptcp_pm_set_flags(struct net *net, struct nlattr *token, 931 struct mptcp_pm_addr_entry *loc, 932 struct mptcp_pm_addr_entry *rem, u8 bkup); 933 int mptcp_pm_nl_set_flags(struct net *net, struct mptcp_pm_addr_entry *addr, u8 bkup); 934 int mptcp_userspace_pm_set_flags(struct net *net, struct nlattr *token, 935 struct mptcp_pm_addr_entry *loc, 936 struct mptcp_pm_addr_entry *rem, u8 bkup); 937 int mptcp_pm_announce_addr(struct mptcp_sock *msk, 938 const struct mptcp_addr_info *addr, 939 bool echo); 940 int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); 941 int mptcp_pm_remove_subflow(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); 942 void mptcp_pm_remove_addrs(struct mptcp_sock *msk, struct list_head *rm_list); 943 void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk, 944 struct list_head *rm_list); 945 946 void mptcp_free_local_addr_list(struct mptcp_sock *msk); 947 948 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk, 949 const struct sock *ssk, gfp_t gfp); 950 void mptcp_event_addr_announced(const struct sock *ssk, const struct mptcp_addr_info *info); 951 void mptcp_event_addr_removed(const struct mptcp_sock *msk, u8 id); 952 void mptcp_event_pm_listener(const struct sock *ssk, 953 enum mptcp_event_type event); 954 bool mptcp_userspace_pm_active(const struct mptcp_sock *msk); 955 956 void __mptcp_fastopen_gen_msk_ackseq(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow, 957 const struct mptcp_options_received *mp_opt); 958 void mptcp_fastopen_subflow_synack_set_params(struct mptcp_subflow_context *subflow, 959 struct request_sock *req); 960 961 static inline bool mptcp_pm_should_add_signal(struct mptcp_sock *msk) 962 { 963 return READ_ONCE(msk->pm.addr_signal) & 964 (BIT(MPTCP_ADD_ADDR_SIGNAL) | BIT(MPTCP_ADD_ADDR_ECHO)); 965 } 966 967 static inline bool mptcp_pm_should_add_signal_addr(struct mptcp_sock *msk) 968 { 969 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_SIGNAL); 970 } 971 972 static inline bool mptcp_pm_should_add_signal_echo(struct mptcp_sock *msk) 973 { 974 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_ECHO); 975 } 976 977 static inline bool mptcp_pm_should_rm_signal(struct mptcp_sock *msk) 978 { 979 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_RM_ADDR_SIGNAL); 980 } 981 982 static inline bool mptcp_pm_is_userspace(const struct mptcp_sock *msk) 983 { 984 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_USERSPACE; 985 } 986 987 static inline bool mptcp_pm_is_kernel(const struct mptcp_sock *msk) 988 { 989 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_KERNEL; 990 } 991 992 static inline unsigned int mptcp_add_addr_len(int family, bool echo, bool port) 993 { 994 u8 len = TCPOLEN_MPTCP_ADD_ADDR_BASE; 995 996 if (family == AF_INET6) 997 len = TCPOLEN_MPTCP_ADD_ADDR6_BASE; 998 if (!echo) 999 len += MPTCPOPT_THMAC_LEN; 1000 /* account for 2 trailing 'nop' options */ 1001 if (port) 1002 len += TCPOLEN_MPTCP_PORT_LEN + TCPOLEN_MPTCP_PORT_ALIGN; 1003 1004 return len; 1005 } 1006 1007 static inline int mptcp_rm_addr_len(const struct mptcp_rm_list *rm_list) 1008 { 1009 if (rm_list->nr == 0 || rm_list->nr > MPTCP_RM_IDS_MAX) 1010 return -EINVAL; 1011 1012 return TCPOLEN_MPTCP_RM_ADDR_BASE + roundup(rm_list->nr - 1, 4) + 1; 1013 } 1014 1015 bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, const struct sk_buff *skb, 1016 unsigned int opt_size, unsigned int remaining, 1017 struct mptcp_addr_info *addr, bool *echo, 1018 bool *drop_other_suboptions); 1019 bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining, 1020 struct mptcp_rm_list *rm_list); 1021 int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc); 1022 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc); 1023 int mptcp_userspace_pm_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc); 1024 1025 void __init mptcp_pm_nl_init(void); 1026 void mptcp_pm_nl_work(struct mptcp_sock *msk); 1027 void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk, 1028 const struct mptcp_rm_list *rm_list); 1029 unsigned int mptcp_pm_get_add_addr_signal_max(const struct mptcp_sock *msk); 1030 unsigned int mptcp_pm_get_add_addr_accept_max(const struct mptcp_sock *msk); 1031 unsigned int mptcp_pm_get_subflows_max(const struct mptcp_sock *msk); 1032 unsigned int mptcp_pm_get_local_addr_max(const struct mptcp_sock *msk); 1033 1034 /* called under PM lock */ 1035 static inline void __mptcp_pm_close_subflow(struct mptcp_sock *msk) 1036 { 1037 if (--msk->pm.subflows < mptcp_pm_get_subflows_max(msk)) 1038 WRITE_ONCE(msk->pm.accept_subflow, true); 1039 } 1040 1041 static inline void mptcp_pm_close_subflow(struct mptcp_sock *msk) 1042 { 1043 spin_lock_bh(&msk->pm.lock); 1044 __mptcp_pm_close_subflow(msk); 1045 spin_unlock_bh(&msk->pm.lock); 1046 } 1047 1048 void mptcp_sockopt_sync(struct mptcp_sock *msk, struct sock *ssk); 1049 void mptcp_sockopt_sync_locked(struct mptcp_sock *msk, struct sock *ssk); 1050 1051 static inline struct mptcp_ext *mptcp_get_ext(const struct sk_buff *skb) 1052 { 1053 return (struct mptcp_ext *)skb_ext_find(skb, SKB_EXT_MPTCP); 1054 } 1055 1056 void mptcp_diag_subflow_init(struct tcp_ulp_ops *ops); 1057 1058 static inline bool __mptcp_check_fallback(const struct mptcp_sock *msk) 1059 { 1060 return test_bit(MPTCP_FALLBACK_DONE, &msk->flags); 1061 } 1062 1063 static inline bool mptcp_check_fallback(const struct sock *sk) 1064 { 1065 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 1066 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 1067 1068 return __mptcp_check_fallback(msk); 1069 } 1070 1071 static inline void __mptcp_do_fallback(struct mptcp_sock *msk) 1072 { 1073 if (__mptcp_check_fallback(msk)) { 1074 pr_debug("TCP fallback already done (msk=%p)", msk); 1075 return; 1076 } 1077 set_bit(MPTCP_FALLBACK_DONE, &msk->flags); 1078 } 1079 1080 static inline bool __mptcp_has_initial_subflow(const struct mptcp_sock *msk) 1081 { 1082 struct sock *ssk = READ_ONCE(msk->first); 1083 1084 return ssk && ((1 << inet_sk_state_load(ssk)) & 1085 (TCPF_ESTABLISHED | TCPF_SYN_SENT | 1086 TCPF_SYN_RECV | TCPF_LISTEN)); 1087 } 1088 1089 static inline void mptcp_do_fallback(struct sock *ssk) 1090 { 1091 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 1092 struct sock *sk = subflow->conn; 1093 struct mptcp_sock *msk; 1094 1095 msk = mptcp_sk(sk); 1096 __mptcp_do_fallback(msk); 1097 if (READ_ONCE(msk->snd_data_fin_enable) && !(ssk->sk_shutdown & SEND_SHUTDOWN)) { 1098 gfp_t saved_allocation = ssk->sk_allocation; 1099 1100 /* we are in a atomic (BH) scope, override ssk default for data 1101 * fin allocation 1102 */ 1103 ssk->sk_allocation = GFP_ATOMIC; 1104 ssk->sk_shutdown |= SEND_SHUTDOWN; 1105 tcp_shutdown(ssk, SEND_SHUTDOWN); 1106 ssk->sk_allocation = saved_allocation; 1107 } 1108 } 1109 1110 #define pr_fallback(a) pr_debug("%s:fallback to TCP (msk=%p)", __func__, a) 1111 1112 static inline bool mptcp_check_infinite_map(struct sk_buff *skb) 1113 { 1114 struct mptcp_ext *mpext; 1115 1116 mpext = skb ? mptcp_get_ext(skb) : NULL; 1117 if (mpext && mpext->infinite_map) 1118 return true; 1119 1120 return false; 1121 } 1122 1123 static inline bool is_active_ssk(struct mptcp_subflow_context *subflow) 1124 { 1125 return (subflow->request_mptcp || subflow->request_join); 1126 } 1127 1128 static inline bool subflow_simultaneous_connect(struct sock *sk) 1129 { 1130 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 1131 1132 return (1 << sk->sk_state) & 1133 (TCPF_ESTABLISHED | TCPF_FIN_WAIT1 | TCPF_FIN_WAIT2 | TCPF_CLOSING) && 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