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 #define MPTCP_SUPPORTED_VERSION 1 17 18 /* MPTCP option bits */ 19 #define OPTION_MPTCP_MPC_SYN BIT(0) 20 #define OPTION_MPTCP_MPC_SYNACK BIT(1) 21 #define OPTION_MPTCP_MPC_ACK BIT(2) 22 #define OPTION_MPTCP_MPJ_SYN BIT(3) 23 #define OPTION_MPTCP_MPJ_SYNACK BIT(4) 24 #define OPTION_MPTCP_MPJ_ACK BIT(5) 25 #define OPTION_MPTCP_ADD_ADDR BIT(6) 26 #define OPTION_MPTCP_RM_ADDR BIT(7) 27 #define OPTION_MPTCP_FASTCLOSE BIT(8) 28 #define OPTION_MPTCP_PRIO BIT(9) 29 #define OPTION_MPTCP_RST BIT(10) 30 #define OPTION_MPTCP_DSS BIT(11) 31 #define OPTION_MPTCP_FAIL BIT(12) 32 33 #define OPTION_MPTCP_CSUMREQD BIT(13) 34 35 #define OPTIONS_MPTCP_MPC (OPTION_MPTCP_MPC_SYN | OPTION_MPTCP_MPC_SYNACK | \ 36 OPTION_MPTCP_MPC_ACK) 37 #define OPTIONS_MPTCP_MPJ (OPTION_MPTCP_MPJ_SYN | OPTION_MPTCP_MPJ_SYNACK | \ 38 OPTION_MPTCP_MPJ_ACK) 39 40 /* MPTCP option subtypes */ 41 #define MPTCPOPT_MP_CAPABLE 0 42 #define MPTCPOPT_MP_JOIN 1 43 #define MPTCPOPT_DSS 2 44 #define MPTCPOPT_ADD_ADDR 3 45 #define MPTCPOPT_RM_ADDR 4 46 #define MPTCPOPT_MP_PRIO 5 47 #define MPTCPOPT_MP_FAIL 6 48 #define MPTCPOPT_MP_FASTCLOSE 7 49 #define MPTCPOPT_RST 8 50 51 /* MPTCP suboption lengths */ 52 #define TCPOLEN_MPTCP_MPC_SYN 4 53 #define TCPOLEN_MPTCP_MPC_SYNACK 12 54 #define TCPOLEN_MPTCP_MPC_ACK 20 55 #define TCPOLEN_MPTCP_MPC_ACK_DATA 22 56 #define TCPOLEN_MPTCP_MPJ_SYN 12 57 #define TCPOLEN_MPTCP_MPJ_SYNACK 16 58 #define TCPOLEN_MPTCP_MPJ_ACK 24 59 #define TCPOLEN_MPTCP_DSS_BASE 4 60 #define TCPOLEN_MPTCP_DSS_ACK32 4 61 #define TCPOLEN_MPTCP_DSS_ACK64 8 62 #define TCPOLEN_MPTCP_DSS_MAP32 10 63 #define TCPOLEN_MPTCP_DSS_MAP64 14 64 #define TCPOLEN_MPTCP_DSS_CHECKSUM 2 65 #define TCPOLEN_MPTCP_ADD_ADDR 16 66 #define TCPOLEN_MPTCP_ADD_ADDR_PORT 18 67 #define TCPOLEN_MPTCP_ADD_ADDR_BASE 8 68 #define TCPOLEN_MPTCP_ADD_ADDR_BASE_PORT 10 69 #define TCPOLEN_MPTCP_ADD_ADDR6 28 70 #define TCPOLEN_MPTCP_ADD_ADDR6_PORT 30 71 #define TCPOLEN_MPTCP_ADD_ADDR6_BASE 20 72 #define TCPOLEN_MPTCP_ADD_ADDR6_BASE_PORT 22 73 #define TCPOLEN_MPTCP_PORT_LEN 2 74 #define TCPOLEN_MPTCP_PORT_ALIGN 2 75 #define TCPOLEN_MPTCP_RM_ADDR_BASE 3 76 #define TCPOLEN_MPTCP_PRIO 3 77 #define TCPOLEN_MPTCP_PRIO_ALIGN 4 78 #define TCPOLEN_MPTCP_FASTCLOSE 12 79 #define TCPOLEN_MPTCP_RST 4 80 #define TCPOLEN_MPTCP_FAIL 12 81 82 #define TCPOLEN_MPTCP_MPC_ACK_DATA_CSUM (TCPOLEN_MPTCP_DSS_CHECKSUM + TCPOLEN_MPTCP_MPC_ACK_DATA) 83 84 /* MPTCP MP_JOIN flags */ 85 #define MPTCPOPT_BACKUP BIT(0) 86 #define MPTCPOPT_THMAC_LEN 8 87 88 /* MPTCP MP_CAPABLE flags */ 89 #define MPTCP_VERSION_MASK (0x0F) 90 #define MPTCP_CAP_CHECKSUM_REQD BIT(7) 91 #define MPTCP_CAP_EXTENSIBILITY BIT(6) 92 #define MPTCP_CAP_DENY_JOIN_ID0 BIT(5) 93 #define MPTCP_CAP_HMAC_SHA256 BIT(0) 94 #define MPTCP_CAP_FLAG_MASK (0x1F) 95 96 /* MPTCP DSS flags */ 97 #define MPTCP_DSS_DATA_FIN BIT(4) 98 #define MPTCP_DSS_DSN64 BIT(3) 99 #define MPTCP_DSS_HAS_MAP BIT(2) 100 #define MPTCP_DSS_ACK64 BIT(1) 101 #define MPTCP_DSS_HAS_ACK BIT(0) 102 #define MPTCP_DSS_FLAG_MASK (0x1F) 103 104 /* MPTCP ADD_ADDR flags */ 105 #define MPTCP_ADDR_ECHO BIT(0) 106 107 /* MPTCP MP_PRIO flags */ 108 #define MPTCP_PRIO_BKUP BIT(0) 109 110 /* MPTCP TCPRST flags */ 111 #define MPTCP_RST_TRANSIENT BIT(0) 112 113 /* MPTCP socket atomic flags */ 114 #define MPTCP_NOSPACE 1 115 #define MPTCP_WORK_RTX 2 116 #define MPTCP_FALLBACK_DONE 4 117 #define MPTCP_WORK_CLOSE_SUBFLOW 5 118 119 /* MPTCP socket release cb flags */ 120 #define MPTCP_PUSH_PENDING 1 121 #define MPTCP_CLEAN_UNA 2 122 #define MPTCP_ERROR_REPORT 3 123 #define MPTCP_RETRANSMIT 4 124 #define MPTCP_FLUSH_JOIN_LIST 5 125 #define MPTCP_SYNC_STATE 6 126 #define MPTCP_SYNC_SNDBUF 7 127 128 struct mptcp_skb_cb { 129 u64 map_seq; 130 u64 end_seq; 131 u32 offset; 132 u8 has_rxtstamp:1; 133 }; 134 135 #define MPTCP_SKB_CB(__skb) ((struct mptcp_skb_cb *)&((__skb)->cb[0])) 136 137 static inline bool before64(__u64 seq1, __u64 seq2) 138 { 139 return (__s64)(seq1 - seq2) < 0; 140 } 141 142 #define after64(seq2, seq1) before64(seq1, seq2) 143 144 struct mptcp_options_received { 145 u64 sndr_key; 146 u64 rcvr_key; 147 u64 data_ack; 148 u64 data_seq; 149 u32 subflow_seq; 150 u16 data_len; 151 __sum16 csum; 152 u16 suboptions; 153 u32 token; 154 u32 nonce; 155 u16 use_map:1, 156 dsn64:1, 157 data_fin:1, 158 use_ack:1, 159 ack64:1, 160 mpc_map:1, 161 reset_reason:4, 162 reset_transient:1, 163 echo:1, 164 backup:1, 165 deny_join_id0:1, 166 __unused:2; 167 u8 join_id; 168 u64 thmac; 169 u8 hmac[MPTCPOPT_HMAC_LEN]; 170 struct mptcp_addr_info addr; 171 struct mptcp_rm_list rm_list; 172 u64 ahmac; 173 u64 fail_seq; 174 }; 175 176 static inline __be32 mptcp_option(u8 subopt, u8 len, u8 nib, u8 field) 177 { 178 return htonl((TCPOPT_MPTCP << 24) | (len << 16) | (subopt << 12) | 179 ((nib & 0xF) << 8) | field); 180 } 181 182 enum mptcp_pm_status { 183 MPTCP_PM_ADD_ADDR_RECEIVED, 184 MPTCP_PM_ADD_ADDR_SEND_ACK, 185 MPTCP_PM_RM_ADDR_RECEIVED, 186 MPTCP_PM_ESTABLISHED, 187 MPTCP_PM_SUBFLOW_ESTABLISHED, 188 MPTCP_PM_ALREADY_ESTABLISHED, /* persistent status, set after ESTABLISHED event */ 189 MPTCP_PM_MPC_ENDPOINT_ACCOUNTED /* persistent status, set after MPC local address is 190 * accounted int id_avail_bitmap 191 */ 192 }; 193 194 enum mptcp_pm_type { 195 MPTCP_PM_TYPE_KERNEL = 0, 196 MPTCP_PM_TYPE_USERSPACE, 197 198 __MPTCP_PM_TYPE_NR, 199 __MPTCP_PM_TYPE_MAX = __MPTCP_PM_TYPE_NR - 1, 200 }; 201 202 /* Status bits below MPTCP_PM_ALREADY_ESTABLISHED need pm worker actions */ 203 #define MPTCP_PM_WORK_MASK ((1 << MPTCP_PM_ALREADY_ESTABLISHED) - 1) 204 205 enum mptcp_addr_signal_status { 206 MPTCP_ADD_ADDR_SIGNAL, 207 MPTCP_ADD_ADDR_ECHO, 208 MPTCP_RM_ADDR_SIGNAL, 209 }; 210 211 /* max value of mptcp_addr_info.id */ 212 #define MPTCP_PM_MAX_ADDR_ID U8_MAX 213 214 struct mptcp_pm_data { 215 struct mptcp_addr_info local; 216 struct mptcp_addr_info remote; 217 struct list_head anno_list; 218 struct list_head userspace_pm_local_addr_list; 219 220 spinlock_t lock; /*protects the whole PM data */ 221 222 u8 addr_signal; 223 bool server_side; 224 bool work_pending; 225 bool accept_addr; 226 bool accept_subflow; 227 bool remote_deny_join_id0; 228 u8 add_addr_signaled; 229 u8 add_addr_accepted; 230 u8 local_addr_used; 231 u8 pm_type; 232 u8 subflows; 233 u8 status; 234 DECLARE_BITMAP(id_avail_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); 235 struct mptcp_rm_list rm_list_tx; 236 struct mptcp_rm_list rm_list_rx; 237 }; 238 239 struct mptcp_pm_addr_entry { 240 struct list_head list; 241 struct mptcp_addr_info addr; 242 u8 flags; 243 int ifindex; 244 struct socket *lsk; 245 }; 246 247 struct mptcp_data_frag { 248 struct list_head list; 249 u64 data_seq; 250 u16 data_len; 251 u16 offset; 252 u16 overhead; 253 u16 already_sent; 254 struct page *page; 255 }; 256 257 /* MPTCP connection sock */ 258 struct mptcp_sock { 259 /* inet_connection_sock must be the first member */ 260 struct inet_connection_sock sk; 261 u64 local_key; 262 u64 remote_key; 263 u64 write_seq; 264 u64 bytes_sent; 265 u64 snd_nxt; 266 u64 bytes_received; 267 u64 ack_seq; 268 atomic64_t rcv_wnd_sent; 269 u64 rcv_data_fin_seq; 270 u64 bytes_retrans; 271 u64 bytes_consumed; 272 int rmem_fwd_alloc; 273 int snd_burst; 274 int old_wspace; 275 u64 recovery_snd_nxt; /* in recovery mode accept up to this seq; 276 * recovery related fields are under data_lock 277 * protection 278 */ 279 u64 bytes_acked; 280 u64 snd_una; 281 u64 wnd_end; 282 unsigned long timer_ival; 283 u32 token; 284 int rmem_released; 285 unsigned long flags; 286 unsigned long cb_flags; 287 bool recovery; /* closing subflow write queue reinjected */ 288 bool can_ack; 289 bool fully_established; 290 bool rcv_data_fin; 291 bool snd_data_fin_enable; 292 bool rcv_fastclose; 293 bool use_64bit_ack; /* Set when we received a 64-bit DSN */ 294 bool csum_enabled; 295 bool allow_infinite_fallback; 296 u8 pending_state; /* A subflow asked to set this sk_state, 297 * protected by the msk data lock 298 */ 299 u8 mpc_endpoint_id; 300 u8 recvmsg_inq:1, 301 cork:1, 302 nodelay:1, 303 fastopening:1, 304 in_accept_queue:1, 305 free_first:1, 306 rcvspace_init:1; 307 int keepalive_cnt; 308 int keepalive_idle; 309 int keepalive_intvl; 310 struct work_struct work; 311 struct sk_buff *ooo_last_skb; 312 struct rb_root out_of_order_queue; 313 struct sk_buff_head receive_queue; 314 struct list_head conn_list; 315 struct list_head rtx_queue; 316 struct mptcp_data_frag *first_pending; 317 struct list_head join_list; 318 struct sock *first; /* The mptcp ops can safely dereference, using suitable 319 * ONCE annotation, the subflow outside the socket 320 * lock as such sock is freed after close(). 321 */ 322 struct mptcp_pm_data pm; 323 struct mptcp_sched_ops *sched; 324 struct { 325 u32 space; /* bytes copied in last measurement window */ 326 u32 copied; /* bytes copied in this measurement window */ 327 u64 time; /* start time of measurement window */ 328 u64 rtt_us; /* last maximum rtt of subflows */ 329 } rcvq_space; 330 u8 scaling_ratio; 331 332 u32 subflow_id; 333 u32 setsockopt_seq; 334 char ca_name[TCP_CA_NAME_MAX]; 335 }; 336 337 #define mptcp_data_lock(sk) spin_lock_bh(&(sk)->sk_lock.slock) 338 #define mptcp_data_unlock(sk) spin_unlock_bh(&(sk)->sk_lock.slock) 339 340 #define mptcp_for_each_subflow(__msk, __subflow) \ 341 list_for_each_entry(__subflow, &((__msk)->conn_list), node) 342 #define mptcp_for_each_subflow_safe(__msk, __subflow, __tmp) \ 343 list_for_each_entry_safe(__subflow, __tmp, &((__msk)->conn_list), node) 344 345 static inline void msk_owned_by_me(const struct mptcp_sock *msk) 346 { 347 sock_owned_by_me((const struct sock *)msk); 348 } 349 350 #define mptcp_sk(ptr) container_of_const(ptr, struct mptcp_sock, sk.icsk_inet.sk) 351 352 /* the msk socket don't use the backlog, also account for the bulk 353 * free memory 354 */ 355 static inline int __mptcp_rmem(const struct sock *sk) 356 { 357 return atomic_read(&sk->sk_rmem_alloc) - READ_ONCE(mptcp_sk(sk)->rmem_released); 358 } 359 360 static inline int mptcp_win_from_space(const struct sock *sk, int space) 361 { 362 return __tcp_win_from_space(mptcp_sk(sk)->scaling_ratio, space); 363 } 364 365 static inline int __mptcp_space(const struct sock *sk) 366 { 367 return mptcp_win_from_space(sk, READ_ONCE(sk->sk_rcvbuf) - __mptcp_rmem(sk)); 368 } 369 370 static inline struct mptcp_data_frag *mptcp_send_head(const struct sock *sk) 371 { 372 const struct mptcp_sock *msk = mptcp_sk(sk); 373 374 return READ_ONCE(msk->first_pending); 375 } 376 377 static inline struct mptcp_data_frag *mptcp_send_next(struct sock *sk) 378 { 379 struct mptcp_sock *msk = mptcp_sk(sk); 380 struct mptcp_data_frag *cur; 381 382 cur = msk->first_pending; 383 return list_is_last(&cur->list, &msk->rtx_queue) ? NULL : 384 list_next_entry(cur, list); 385 } 386 387 static inline struct mptcp_data_frag *mptcp_pending_tail(const struct sock *sk) 388 { 389 const struct mptcp_sock *msk = mptcp_sk(sk); 390 391 if (!msk->first_pending) 392 return NULL; 393 394 if (WARN_ON_ONCE(list_empty(&msk->rtx_queue))) 395 return NULL; 396 397 return list_last_entry(&msk->rtx_queue, struct mptcp_data_frag, list); 398 } 399 400 static inline struct mptcp_data_frag *mptcp_rtx_head(struct sock *sk) 401 { 402 struct mptcp_sock *msk = mptcp_sk(sk); 403 404 if (msk->snd_una == READ_ONCE(msk->snd_nxt)) 405 return NULL; 406 407 return list_first_entry_or_null(&msk->rtx_queue, struct mptcp_data_frag, list); 408 } 409 410 struct csum_pseudo_header { 411 __be64 data_seq; 412 __be32 subflow_seq; 413 __be16 data_len; 414 __sum16 csum; 415 }; 416 417 struct mptcp_subflow_request_sock { 418 struct tcp_request_sock sk; 419 u16 mp_capable : 1, 420 mp_join : 1, 421 backup : 1, 422 csum_reqd : 1, 423 allow_join_id0 : 1; 424 u8 local_id; 425 u8 remote_id; 426 u64 local_key; 427 u64 idsn; 428 u32 token; 429 u32 ssn_offset; 430 u64 thmac; 431 u32 local_nonce; 432 u32 remote_nonce; 433 struct mptcp_sock *msk; 434 struct hlist_nulls_node token_node; 435 }; 436 437 static inline struct mptcp_subflow_request_sock * 438 mptcp_subflow_rsk(const struct request_sock *rsk) 439 { 440 return (struct mptcp_subflow_request_sock *)rsk; 441 } 442 443 enum mptcp_data_avail { 444 MPTCP_SUBFLOW_NODATA, 445 MPTCP_SUBFLOW_DATA_AVAIL, 446 }; 447 448 struct mptcp_delegated_action { 449 struct napi_struct napi; 450 struct list_head head; 451 }; 452 453 DECLARE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions); 454 455 #define MPTCP_DELEGATE_SCHEDULED 0 456 #define MPTCP_DELEGATE_SEND 1 457 #define MPTCP_DELEGATE_ACK 2 458 #define MPTCP_DELEGATE_SNDBUF 3 459 460 #define MPTCP_DELEGATE_ACTIONS_MASK (~BIT(MPTCP_DELEGATE_SCHEDULED)) 461 /* MPTCP subflow context */ 462 struct mptcp_subflow_context { 463 struct list_head node;/* conn_list of subflows */ 464 465 struct_group(reset, 466 467 unsigned long avg_pacing_rate; /* protected by msk socket lock */ 468 u64 local_key; 469 u64 remote_key; 470 u64 idsn; 471 u64 map_seq; 472 u32 snd_isn; 473 u32 token; 474 u32 rel_write_seq; 475 u32 map_subflow_seq; 476 u32 ssn_offset; 477 u32 map_data_len; 478 __wsum map_data_csum; 479 u32 map_csum_len; 480 u32 request_mptcp : 1, /* send MP_CAPABLE */ 481 request_join : 1, /* send MP_JOIN */ 482 request_bkup : 1, 483 mp_capable : 1, /* remote is MPTCP capable */ 484 mp_join : 1, /* remote is JOINing */ 485 fully_established : 1, /* path validated */ 486 pm_notified : 1, /* PM hook called for established status */ 487 conn_finished : 1, 488 map_valid : 1, 489 map_csum_reqd : 1, 490 map_data_fin : 1, 491 mpc_map : 1, 492 backup : 1, 493 send_mp_prio : 1, 494 send_mp_fail : 1, 495 send_fastclose : 1, 496 send_infinite_map : 1, 497 remote_key_valid : 1, /* received the peer key from */ 498 disposable : 1, /* ctx can be free at ulp release time */ 499 stale : 1, /* unable to snd/rcv data, do not use for xmit */ 500 valid_csum_seen : 1, /* at least one csum validated */ 501 is_mptfo : 1, /* subflow is doing TFO */ 502 __unused : 10; 503 enum mptcp_data_avail data_avail; 504 bool scheduled; 505 u32 remote_nonce; 506 u64 thmac; 507 u32 local_nonce; 508 u32 remote_token; 509 union { 510 u8 hmac[MPTCPOPT_HMAC_LEN]; /* MPJ subflow only */ 511 u64 iasn; /* initial ack sequence number, MPC subflows only */ 512 }; 513 s16 local_id; /* if negative not initialized yet */ 514 u8 remote_id; 515 u8 reset_seen:1; 516 u8 reset_transient:1; 517 u8 reset_reason:4; 518 u8 stale_count; 519 520 u32 subflow_id; 521 522 long delegated_status; 523 unsigned long fail_tout; 524 525 ); 526 527 struct list_head delegated_node; /* link into delegated_action, protected by local BH */ 528 529 u32 setsockopt_seq; 530 u32 stale_rcv_tstamp; 531 int cached_sndbuf; /* sndbuf size when last synced with the msk sndbuf, 532 * protected by the msk socket lock 533 */ 534 535 struct sock *tcp_sock; /* tcp sk backpointer */ 536 struct sock *conn; /* parent mptcp_sock */ 537 const struct inet_connection_sock_af_ops *icsk_af_ops; 538 void (*tcp_state_change)(struct sock *sk); 539 void (*tcp_error_report)(struct sock *sk); 540 541 struct rcu_head rcu; 542 }; 543 544 static inline struct mptcp_subflow_context * 545 mptcp_subflow_ctx(const struct sock *sk) 546 { 547 struct inet_connection_sock *icsk = inet_csk(sk); 548 549 /* Use RCU on icsk_ulp_data only for sock diag code */ 550 return (__force struct mptcp_subflow_context *)icsk->icsk_ulp_data; 551 } 552 553 static inline struct sock * 554 mptcp_subflow_tcp_sock(const struct mptcp_subflow_context *subflow) 555 { 556 return subflow->tcp_sock; 557 } 558 559 static inline void 560 mptcp_subflow_ctx_reset(struct mptcp_subflow_context *subflow) 561 { 562 memset(&subflow->reset, 0, sizeof(subflow->reset)); 563 subflow->request_mptcp = 1; 564 WRITE_ONCE(subflow->local_id, -1); 565 } 566 567 static inline u64 568 mptcp_subflow_get_map_offset(const struct mptcp_subflow_context *subflow) 569 { 570 return tcp_sk(mptcp_subflow_tcp_sock(subflow))->copied_seq - 571 subflow->ssn_offset - 572 subflow->map_subflow_seq; 573 } 574 575 static inline u64 576 mptcp_subflow_get_mapped_dsn(const struct mptcp_subflow_context *subflow) 577 { 578 return subflow->map_seq + mptcp_subflow_get_map_offset(subflow); 579 } 580 581 void mptcp_subflow_process_delegated(struct sock *ssk, long actions); 582 583 static inline void mptcp_subflow_delegate(struct mptcp_subflow_context *subflow, int action) 584 { 585 long old, set_bits = BIT(MPTCP_DELEGATE_SCHEDULED) | BIT(action); 586 struct mptcp_delegated_action *delegated; 587 bool schedule; 588 589 /* the caller held the subflow bh socket lock */ 590 lockdep_assert_in_softirq(); 591 592 /* The implied barrier pairs with tcp_release_cb_override() 593 * mptcp_napi_poll(), and ensures the below list check sees list 594 * updates done prior to delegated status bits changes 595 */ 596 old = set_mask_bits(&subflow->delegated_status, 0, set_bits); 597 if (!(old & BIT(MPTCP_DELEGATE_SCHEDULED))) { 598 if (WARN_ON_ONCE(!list_empty(&subflow->delegated_node))) 599 return; 600 601 delegated = this_cpu_ptr(&mptcp_delegated_actions); 602 schedule = list_empty(&delegated->head); 603 list_add_tail(&subflow->delegated_node, &delegated->head); 604 sock_hold(mptcp_subflow_tcp_sock(subflow)); 605 if (schedule) 606 napi_schedule(&delegated->napi); 607 } 608 } 609 610 static inline struct mptcp_subflow_context * 611 mptcp_subflow_delegated_next(struct mptcp_delegated_action *delegated) 612 { 613 struct mptcp_subflow_context *ret; 614 615 if (list_empty(&delegated->head)) 616 return NULL; 617 618 ret = list_first_entry(&delegated->head, struct mptcp_subflow_context, delegated_node); 619 list_del_init(&ret->delegated_node); 620 return ret; 621 } 622 623 int mptcp_is_enabled(const struct net *net); 624 unsigned int mptcp_get_add_addr_timeout(const struct net *net); 625 int mptcp_is_checksum_enabled(const struct net *net); 626 int mptcp_allow_join_id0(const struct net *net); 627 unsigned int mptcp_stale_loss_cnt(const struct net *net); 628 int mptcp_get_pm_type(const struct net *net); 629 const char *mptcp_get_scheduler(const struct net *net); 630 void __mptcp_subflow_fully_established(struct mptcp_sock *msk, 631 struct mptcp_subflow_context *subflow, 632 const struct mptcp_options_received *mp_opt); 633 bool __mptcp_retransmit_pending_data(struct sock *sk); 634 void mptcp_check_and_set_pending(struct sock *sk); 635 void __mptcp_push_pending(struct sock *sk, unsigned int flags); 636 bool mptcp_subflow_data_available(struct sock *sk); 637 void __init mptcp_subflow_init(void); 638 void mptcp_subflow_shutdown(struct sock *sk, struct sock *ssk, int how); 639 void mptcp_close_ssk(struct sock *sk, struct sock *ssk, 640 struct mptcp_subflow_context *subflow); 641 void __mptcp_subflow_send_ack(struct sock *ssk); 642 void mptcp_subflow_reset(struct sock *ssk); 643 void mptcp_subflow_queue_clean(struct sock *sk, struct sock *ssk); 644 void mptcp_sock_graft(struct sock *sk, struct socket *parent); 645 struct sock *__mptcp_nmpc_sk(struct mptcp_sock *msk); 646 bool __mptcp_close(struct sock *sk, long timeout); 647 void mptcp_cancel_work(struct sock *sk); 648 void __mptcp_unaccepted_force_close(struct sock *sk); 649 void mptcp_set_owner_r(struct sk_buff *skb, struct sock *sk); 650 void mptcp_set_state(struct sock *sk, int state); 651 652 bool mptcp_addresses_equal(const struct mptcp_addr_info *a, 653 const struct mptcp_addr_info *b, bool use_port); 654 void mptcp_local_address(const struct sock_common *skc, struct mptcp_addr_info *addr); 655 656 /* called with sk socket lock held */ 657 int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_addr_info *loc, 658 const struct mptcp_addr_info *remote); 659 int mptcp_subflow_create_socket(struct sock *sk, unsigned short family, 660 struct socket **new_sock); 661 void mptcp_info2sockaddr(const struct mptcp_addr_info *info, 662 struct sockaddr_storage *addr, 663 unsigned short family); 664 struct mptcp_sched_ops *mptcp_sched_find(const char *name); 665 int mptcp_register_scheduler(struct mptcp_sched_ops *sched); 666 void mptcp_unregister_scheduler(struct mptcp_sched_ops *sched); 667 void mptcp_sched_init(void); 668 int mptcp_init_sched(struct mptcp_sock *msk, 669 struct mptcp_sched_ops *sched); 670 void mptcp_release_sched(struct mptcp_sock *msk); 671 void mptcp_subflow_set_scheduled(struct mptcp_subflow_context *subflow, 672 bool scheduled); 673 struct sock *mptcp_subflow_get_send(struct mptcp_sock *msk); 674 struct sock *mptcp_subflow_get_retrans(struct mptcp_sock *msk); 675 int mptcp_sched_get_send(struct mptcp_sock *msk); 676 int mptcp_sched_get_retrans(struct mptcp_sock *msk); 677 678 static inline u64 mptcp_data_avail(const struct mptcp_sock *msk) 679 { 680 return READ_ONCE(msk->bytes_received) - READ_ONCE(msk->bytes_consumed); 681 } 682 683 static inline bool mptcp_epollin_ready(const struct sock *sk) 684 { 685 /* mptcp doesn't have to deal with small skbs in the receive queue, 686 * at it can always coalesce them 687 */ 688 return (mptcp_data_avail(mptcp_sk(sk)) >= sk->sk_rcvlowat) || 689 (mem_cgroup_sockets_enabled && sk->sk_memcg && 690 mem_cgroup_under_socket_pressure(sk->sk_memcg)) || 691 READ_ONCE(tcp_memory_pressure); 692 } 693 694 int mptcp_set_rcvlowat(struct sock *sk, int val); 695 696 static inline bool __tcp_can_send(const struct sock *ssk) 697 { 698 /* only send if our side has not closed yet */ 699 return ((1 << inet_sk_state_load(ssk)) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)); 700 } 701 702 static inline bool __mptcp_subflow_active(struct mptcp_subflow_context *subflow) 703 { 704 /* can't send if JOIN hasn't completed yet (i.e. is usable for mptcp) */ 705 if (subflow->request_join && !subflow->fully_established) 706 return false; 707 708 return __tcp_can_send(mptcp_subflow_tcp_sock(subflow)); 709 } 710 711 void mptcp_subflow_set_active(struct mptcp_subflow_context *subflow); 712 713 bool mptcp_subflow_active(struct mptcp_subflow_context *subflow); 714 715 void mptcp_subflow_drop_ctx(struct sock *ssk); 716 717 static inline void mptcp_subflow_tcp_fallback(struct sock *sk, 718 struct mptcp_subflow_context *ctx) 719 { 720 sk->sk_data_ready = sock_def_readable; 721 sk->sk_state_change = ctx->tcp_state_change; 722 sk->sk_write_space = sk_stream_write_space; 723 sk->sk_error_report = ctx->tcp_error_report; 724 725 inet_csk(sk)->icsk_af_ops = ctx->icsk_af_ops; 726 } 727 728 void __init mptcp_proto_init(void); 729 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 730 int __init mptcp_proto_v6_init(void); 731 #endif 732 733 struct sock *mptcp_sk_clone_init(const struct sock *sk, 734 const struct mptcp_options_received *mp_opt, 735 struct sock *ssk, 736 struct request_sock *req); 737 void mptcp_get_options(const struct sk_buff *skb, 738 struct mptcp_options_received *mp_opt); 739 740 void mptcp_finish_connect(struct sock *sk); 741 void __mptcp_sync_state(struct sock *sk, int state); 742 void mptcp_reset_tout_timer(struct mptcp_sock *msk, unsigned long fail_tout); 743 744 static inline void mptcp_stop_tout_timer(struct sock *sk) 745 { 746 if (!inet_csk(sk)->icsk_mtup.probe_timestamp) 747 return; 748 749 sk_stop_timer(sk, &sk->sk_timer); 750 inet_csk(sk)->icsk_mtup.probe_timestamp = 0; 751 } 752 753 static inline void mptcp_set_close_tout(struct sock *sk, unsigned long tout) 754 { 755 /* avoid 0 timestamp, as that means no close timeout */ 756 inet_csk(sk)->icsk_mtup.probe_timestamp = tout ? : 1; 757 } 758 759 static inline void mptcp_start_tout_timer(struct sock *sk) 760 { 761 mptcp_set_close_tout(sk, tcp_jiffies32); 762 mptcp_reset_tout_timer(mptcp_sk(sk), 0); 763 } 764 765 static inline bool mptcp_is_fully_established(struct sock *sk) 766 { 767 return inet_sk_state_load(sk) == TCP_ESTABLISHED && 768 READ_ONCE(mptcp_sk(sk)->fully_established); 769 } 770 771 void mptcp_rcv_space_init(struct mptcp_sock *msk, const struct sock *ssk); 772 void mptcp_data_ready(struct sock *sk, struct sock *ssk); 773 bool mptcp_finish_join(struct sock *sk); 774 bool mptcp_schedule_work(struct sock *sk); 775 int mptcp_setsockopt(struct sock *sk, int level, int optname, 776 sockptr_t optval, unsigned int optlen); 777 int mptcp_getsockopt(struct sock *sk, int level, int optname, 778 char __user *optval, int __user *option); 779 780 u64 __mptcp_expand_seq(u64 old_seq, u64 cur_seq); 781 static inline u64 mptcp_expand_seq(u64 old_seq, u64 cur_seq, bool use_64bit) 782 { 783 if (use_64bit) 784 return cur_seq; 785 786 return __mptcp_expand_seq(old_seq, cur_seq); 787 } 788 void __mptcp_check_push(struct sock *sk, struct sock *ssk); 789 void __mptcp_data_acked(struct sock *sk); 790 void __mptcp_error_report(struct sock *sk); 791 bool mptcp_update_rcv_data_fin(struct mptcp_sock *msk, u64 data_fin_seq, bool use_64bit); 792 static inline bool mptcp_data_fin_enabled(const struct mptcp_sock *msk) 793 { 794 return READ_ONCE(msk->snd_data_fin_enable) && 795 READ_ONCE(msk->write_seq) == READ_ONCE(msk->snd_nxt); 796 } 797 798 static inline void mptcp_write_space(struct sock *sk) 799 { 800 if (sk_stream_is_writeable(sk)) { 801 /* pairs with memory barrier in mptcp_poll */ 802 smp_mb(); 803 if (test_and_clear_bit(MPTCP_NOSPACE, &mptcp_sk(sk)->flags)) 804 sk_stream_write_space(sk); 805 } 806 } 807 808 static inline void __mptcp_sync_sndbuf(struct sock *sk) 809 { 810 struct mptcp_subflow_context *subflow; 811 int ssk_sndbuf, new_sndbuf; 812 813 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) 814 return; 815 816 new_sndbuf = sock_net(sk)->ipv4.sysctl_tcp_wmem[0]; 817 mptcp_for_each_subflow(mptcp_sk(sk), subflow) { 818 ssk_sndbuf = READ_ONCE(mptcp_subflow_tcp_sock(subflow)->sk_sndbuf); 819 820 subflow->cached_sndbuf = ssk_sndbuf; 821 new_sndbuf += ssk_sndbuf; 822 } 823 824 /* the msk max wmem limit is <nr_subflows> * tcp wmem[2] */ 825 WRITE_ONCE(sk->sk_sndbuf, new_sndbuf); 826 mptcp_write_space(sk); 827 } 828 829 /* The called held both the msk socket and the subflow socket locks, 830 * possibly under BH 831 */ 832 static inline void __mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk) 833 { 834 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 835 836 if (READ_ONCE(ssk->sk_sndbuf) != subflow->cached_sndbuf) 837 __mptcp_sync_sndbuf(sk); 838 } 839 840 /* the caller held only the subflow socket lock, either in process or 841 * BH context. Additionally this can be called under the msk data lock, 842 * so we can't acquire such lock here: let the delegate action acquires 843 * the needed locks in suitable order. 844 */ 845 static inline void mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk) 846 { 847 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 848 849 if (likely(READ_ONCE(ssk->sk_sndbuf) == subflow->cached_sndbuf)) 850 return; 851 852 local_bh_disable(); 853 mptcp_subflow_delegate(subflow, MPTCP_DELEGATE_SNDBUF); 854 local_bh_enable(); 855 } 856 857 void mptcp_destroy_common(struct mptcp_sock *msk, unsigned int flags); 858 859 #define MPTCP_TOKEN_MAX_RETRIES 4 860 861 void __init mptcp_token_init(void); 862 static inline void mptcp_token_init_request(struct request_sock *req) 863 { 864 mptcp_subflow_rsk(req)->token_node.pprev = NULL; 865 } 866 867 int mptcp_token_new_request(struct request_sock *req); 868 void mptcp_token_destroy_request(struct request_sock *req); 869 int mptcp_token_new_connect(struct sock *ssk); 870 void mptcp_token_accept(struct mptcp_subflow_request_sock *r, 871 struct mptcp_sock *msk); 872 bool mptcp_token_exists(u32 token); 873 struct mptcp_sock *mptcp_token_get_sock(struct net *net, u32 token); 874 struct mptcp_sock *mptcp_token_iter_next(const struct net *net, long *s_slot, 875 long *s_num); 876 void mptcp_token_destroy(struct mptcp_sock *msk); 877 878 void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn); 879 880 void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u8 *msg, int len, void *hmac); 881 __sum16 __mptcp_make_csum(u64 data_seq, u32 subflow_seq, u16 data_len, __wsum sum); 882 883 void __init mptcp_pm_init(void); 884 void mptcp_pm_data_init(struct mptcp_sock *msk); 885 void mptcp_pm_data_reset(struct mptcp_sock *msk); 886 int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info, 887 struct mptcp_addr_info *addr); 888 int mptcp_pm_parse_entry(struct nlattr *attr, struct genl_info *info, 889 bool require_family, 890 struct mptcp_pm_addr_entry *entry); 891 bool mptcp_pm_addr_families_match(const struct sock *sk, 892 const struct mptcp_addr_info *loc, 893 const struct mptcp_addr_info *rem); 894 void mptcp_pm_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); 895 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); 896 void mptcp_pm_new_connection(struct mptcp_sock *msk, const struct sock *ssk, int server_side); 897 void mptcp_pm_fully_established(struct mptcp_sock *msk, const struct sock *ssk); 898 bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk); 899 void mptcp_pm_connection_closed(struct mptcp_sock *msk); 900 void mptcp_pm_subflow_established(struct mptcp_sock *msk); 901 bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk); 902 void mptcp_pm_subflow_check_next(struct mptcp_sock *msk, const struct sock *ssk, 903 const struct mptcp_subflow_context *subflow); 904 void mptcp_pm_add_addr_received(const struct sock *ssk, 905 const struct mptcp_addr_info *addr); 906 void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk, 907 const struct mptcp_addr_info *addr); 908 void mptcp_pm_add_addr_send_ack(struct mptcp_sock *msk); 909 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk); 910 void mptcp_pm_rm_addr_received(struct mptcp_sock *msk, 911 const struct mptcp_rm_list *rm_list); 912 void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup); 913 void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq); 914 int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk, 915 struct mptcp_addr_info *addr, 916 struct mptcp_addr_info *rem, 917 u8 bkup); 918 bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk, 919 const struct mptcp_addr_info *addr); 920 void mptcp_pm_free_anno_list(struct mptcp_sock *msk); 921 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk); 922 struct mptcp_pm_add_entry * 923 mptcp_pm_del_add_timer(struct mptcp_sock *msk, 924 const struct mptcp_addr_info *addr, bool check_id); 925 struct mptcp_pm_add_entry * 926 mptcp_lookup_anno_list_by_saddr(const struct mptcp_sock *msk, 927 const struct mptcp_addr_info *addr); 928 int mptcp_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, 929 unsigned int id, 930 u8 *flags, int *ifindex); 931 int mptcp_pm_nl_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, unsigned int id, 932 u8 *flags, int *ifindex); 933 int mptcp_userspace_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, 934 unsigned int id, 935 u8 *flags, int *ifindex); 936 int mptcp_pm_set_flags(struct net *net, struct nlattr *token, 937 struct mptcp_pm_addr_entry *loc, 938 struct mptcp_pm_addr_entry *rem, u8 bkup); 939 int mptcp_pm_nl_set_flags(struct net *net, struct mptcp_pm_addr_entry *addr, u8 bkup); 940 int mptcp_userspace_pm_set_flags(struct net *net, struct nlattr *token, 941 struct mptcp_pm_addr_entry *loc, 942 struct mptcp_pm_addr_entry *rem, u8 bkup); 943 int mptcp_pm_announce_addr(struct mptcp_sock *msk, 944 const struct mptcp_addr_info *addr, 945 bool echo); 946 int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); 947 int mptcp_pm_remove_subflow(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); 948 void mptcp_pm_remove_addrs(struct mptcp_sock *msk, struct list_head *rm_list); 949 void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk, 950 struct list_head *rm_list); 951 952 void mptcp_free_local_addr_list(struct mptcp_sock *msk); 953 int mptcp_nl_cmd_announce(struct sk_buff *skb, struct genl_info *info); 954 int mptcp_nl_cmd_remove(struct sk_buff *skb, struct genl_info *info); 955 int mptcp_nl_cmd_sf_create(struct sk_buff *skb, struct genl_info *info); 956 int mptcp_nl_cmd_sf_destroy(struct sk_buff *skb, struct genl_info *info); 957 958 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk, 959 const struct sock *ssk, gfp_t gfp); 960 void mptcp_event_addr_announced(const struct sock *ssk, const struct mptcp_addr_info *info); 961 void mptcp_event_addr_removed(const struct mptcp_sock *msk, u8 id); 962 void mptcp_event_pm_listener(const struct sock *ssk, 963 enum mptcp_event_type event); 964 bool mptcp_userspace_pm_active(const struct mptcp_sock *msk); 965 966 void __mptcp_fastopen_gen_msk_ackseq(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow, 967 const struct mptcp_options_received *mp_opt); 968 void mptcp_fastopen_subflow_synack_set_params(struct mptcp_subflow_context *subflow, 969 struct request_sock *req); 970 971 static inline bool mptcp_pm_should_add_signal(struct mptcp_sock *msk) 972 { 973 return READ_ONCE(msk->pm.addr_signal) & 974 (BIT(MPTCP_ADD_ADDR_SIGNAL) | BIT(MPTCP_ADD_ADDR_ECHO)); 975 } 976 977 static inline bool mptcp_pm_should_add_signal_addr(struct mptcp_sock *msk) 978 { 979 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_SIGNAL); 980 } 981 982 static inline bool mptcp_pm_should_add_signal_echo(struct mptcp_sock *msk) 983 { 984 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_ECHO); 985 } 986 987 static inline bool mptcp_pm_should_rm_signal(struct mptcp_sock *msk) 988 { 989 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_RM_ADDR_SIGNAL); 990 } 991 992 static inline bool mptcp_pm_is_userspace(const struct mptcp_sock *msk) 993 { 994 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_USERSPACE; 995 } 996 997 static inline bool mptcp_pm_is_kernel(const struct mptcp_sock *msk) 998 { 999 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_KERNEL; 1000 } 1001 1002 static inline unsigned int mptcp_add_addr_len(int family, bool echo, bool port) 1003 { 1004 u8 len = TCPOLEN_MPTCP_ADD_ADDR_BASE; 1005 1006 if (family == AF_INET6) 1007 len = TCPOLEN_MPTCP_ADD_ADDR6_BASE; 1008 if (!echo) 1009 len += MPTCPOPT_THMAC_LEN; 1010 /* account for 2 trailing 'nop' options */ 1011 if (port) 1012 len += TCPOLEN_MPTCP_PORT_LEN + TCPOLEN_MPTCP_PORT_ALIGN; 1013 1014 return len; 1015 } 1016 1017 static inline int mptcp_rm_addr_len(const struct mptcp_rm_list *rm_list) 1018 { 1019 if (rm_list->nr == 0 || rm_list->nr > MPTCP_RM_IDS_MAX) 1020 return -EINVAL; 1021 1022 return TCPOLEN_MPTCP_RM_ADDR_BASE + roundup(rm_list->nr - 1, 4) + 1; 1023 } 1024 1025 bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, const struct sk_buff *skb, 1026 unsigned int opt_size, unsigned int remaining, 1027 struct mptcp_addr_info *addr, bool *echo, 1028 bool *drop_other_suboptions); 1029 bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining, 1030 struct mptcp_rm_list *rm_list); 1031 int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc); 1032 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc); 1033 int mptcp_userspace_pm_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc); 1034 1035 static inline u8 subflow_get_local_id(const struct mptcp_subflow_context *subflow) 1036 { 1037 int local_id = READ_ONCE(subflow->local_id); 1038 1039 if (local_id < 0) 1040 return 0; 1041 return local_id; 1042 } 1043 1044 void __init mptcp_pm_nl_init(void); 1045 void mptcp_pm_nl_work(struct mptcp_sock *msk); 1046 void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk, 1047 const struct mptcp_rm_list *rm_list); 1048 unsigned int mptcp_pm_get_add_addr_signal_max(const struct mptcp_sock *msk); 1049 unsigned int mptcp_pm_get_add_addr_accept_max(const struct mptcp_sock *msk); 1050 unsigned int mptcp_pm_get_subflows_max(const struct mptcp_sock *msk); 1051 unsigned int mptcp_pm_get_local_addr_max(const struct mptcp_sock *msk); 1052 1053 /* called under PM lock */ 1054 static inline void __mptcp_pm_close_subflow(struct mptcp_sock *msk) 1055 { 1056 if (--msk->pm.subflows < mptcp_pm_get_subflows_max(msk)) 1057 WRITE_ONCE(msk->pm.accept_subflow, true); 1058 } 1059 1060 static inline void mptcp_pm_close_subflow(struct mptcp_sock *msk) 1061 { 1062 spin_lock_bh(&msk->pm.lock); 1063 __mptcp_pm_close_subflow(msk); 1064 spin_unlock_bh(&msk->pm.lock); 1065 } 1066 1067 void mptcp_sockopt_sync(struct mptcp_sock *msk, struct sock *ssk); 1068 void mptcp_sockopt_sync_locked(struct mptcp_sock *msk, struct sock *ssk); 1069 1070 static inline struct mptcp_ext *mptcp_get_ext(const struct sk_buff *skb) 1071 { 1072 return (struct mptcp_ext *)skb_ext_find(skb, SKB_EXT_MPTCP); 1073 } 1074 1075 void mptcp_diag_subflow_init(struct tcp_ulp_ops *ops); 1076 1077 static inline bool __mptcp_check_fallback(const struct mptcp_sock *msk) 1078 { 1079 return test_bit(MPTCP_FALLBACK_DONE, &msk->flags); 1080 } 1081 1082 static inline bool mptcp_check_fallback(const struct sock *sk) 1083 { 1084 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 1085 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 1086 1087 return __mptcp_check_fallback(msk); 1088 } 1089 1090 static inline void __mptcp_do_fallback(struct mptcp_sock *msk) 1091 { 1092 if (test_bit(MPTCP_FALLBACK_DONE, &msk->flags)) { 1093 pr_debug("TCP fallback already done (msk=%p)", msk); 1094 return; 1095 } 1096 set_bit(MPTCP_FALLBACK_DONE, &msk->flags); 1097 } 1098 1099 static inline void mptcp_do_fallback(struct sock *ssk) 1100 { 1101 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 1102 struct sock *sk = subflow->conn; 1103 struct mptcp_sock *msk; 1104 1105 msk = mptcp_sk(sk); 1106 __mptcp_do_fallback(msk); 1107 if (READ_ONCE(msk->snd_data_fin_enable) && !(ssk->sk_shutdown & SEND_SHUTDOWN)) { 1108 gfp_t saved_allocation = ssk->sk_allocation; 1109 1110 /* we are in a atomic (BH) scope, override ssk default for data 1111 * fin allocation 1112 */ 1113 ssk->sk_allocation = GFP_ATOMIC; 1114 ssk->sk_shutdown |= SEND_SHUTDOWN; 1115 tcp_shutdown(ssk, SEND_SHUTDOWN); 1116 ssk->sk_allocation = saved_allocation; 1117 } 1118 } 1119 1120 #define pr_fallback(a) pr_debug("%s:fallback to TCP (msk=%p)", __func__, a) 1121 1122 static inline bool mptcp_check_infinite_map(struct sk_buff *skb) 1123 { 1124 struct mptcp_ext *mpext; 1125 1126 mpext = skb ? mptcp_get_ext(skb) : NULL; 1127 if (mpext && mpext->infinite_map) 1128 return true; 1129 1130 return false; 1131 } 1132 1133 static inline bool is_active_ssk(struct mptcp_subflow_context *subflow) 1134 { 1135 return (subflow->request_mptcp || subflow->request_join); 1136 } 1137 1138 static inline bool subflow_simultaneous_connect(struct sock *sk) 1139 { 1140 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 1141 1142 return (1 << sk->sk_state) & 1143 (TCPF_ESTABLISHED | TCPF_FIN_WAIT1 | TCPF_FIN_WAIT2 | TCPF_CLOSING) && 1144 is_active_ssk(subflow) && 1145 !subflow->conn_finished; 1146 } 1147 1148 #ifdef CONFIG_SYN_COOKIES 1149 void subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 1150 struct sk_buff *skb); 1151 bool mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 1152 struct sk_buff *skb); 1153 void __init mptcp_join_cookie_init(void); 1154 #else 1155 static inline void 1156 subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 1157 struct sk_buff *skb) {} 1158 static inline bool 1159 mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 1160 struct sk_buff *skb) 1161 { 1162 return false; 1163 } 1164 1165 static inline void mptcp_join_cookie_init(void) {} 1166 #endif 1167 1168 #endif /* __MPTCP_PROTOCOL_H */ 1169