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 15 #define MPTCP_SUPPORTED_VERSION 1 16 17 /* MPTCP option bits */ 18 #define OPTION_MPTCP_MPC_SYN BIT(0) 19 #define OPTION_MPTCP_MPC_SYNACK BIT(1) 20 #define OPTION_MPTCP_MPC_ACK BIT(2) 21 #define OPTION_MPTCP_MPJ_SYN BIT(3) 22 #define OPTION_MPTCP_MPJ_SYNACK BIT(4) 23 #define OPTION_MPTCP_MPJ_ACK BIT(5) 24 #define OPTION_MPTCP_ADD_ADDR BIT(6) 25 #define OPTION_MPTCP_RM_ADDR BIT(7) 26 #define OPTION_MPTCP_FASTCLOSE BIT(8) 27 #define OPTION_MPTCP_PRIO BIT(9) 28 #define OPTION_MPTCP_RST BIT(10) 29 #define OPTION_MPTCP_DSS BIT(11) 30 #define OPTION_MPTCP_FAIL BIT(12) 31 32 #define OPTION_MPTCP_CSUMREQD BIT(13) 33 34 #define OPTIONS_MPTCP_MPC (OPTION_MPTCP_MPC_SYN | OPTION_MPTCP_MPC_SYNACK | \ 35 OPTION_MPTCP_MPC_ACK) 36 #define OPTIONS_MPTCP_MPJ (OPTION_MPTCP_MPJ_SYN | OPTION_MPTCP_MPJ_SYNACK | \ 37 OPTION_MPTCP_MPJ_ACK) 38 39 /* MPTCP option subtypes */ 40 #define MPTCPOPT_MP_CAPABLE 0 41 #define MPTCPOPT_MP_JOIN 1 42 #define MPTCPOPT_DSS 2 43 #define MPTCPOPT_ADD_ADDR 3 44 #define MPTCPOPT_RM_ADDR 4 45 #define MPTCPOPT_MP_PRIO 5 46 #define MPTCPOPT_MP_FAIL 6 47 #define MPTCPOPT_MP_FASTCLOSE 7 48 #define MPTCPOPT_RST 8 49 50 /* MPTCP suboption lengths */ 51 #define TCPOLEN_MPTCP_MPC_SYN 4 52 #define TCPOLEN_MPTCP_MPC_SYNACK 12 53 #define TCPOLEN_MPTCP_MPC_ACK 20 54 #define TCPOLEN_MPTCP_MPC_ACK_DATA 22 55 #define TCPOLEN_MPTCP_MPJ_SYN 12 56 #define TCPOLEN_MPTCP_MPJ_SYNACK 16 57 #define TCPOLEN_MPTCP_MPJ_ACK 24 58 #define TCPOLEN_MPTCP_DSS_BASE 4 59 #define TCPOLEN_MPTCP_DSS_ACK32 4 60 #define TCPOLEN_MPTCP_DSS_ACK64 8 61 #define TCPOLEN_MPTCP_DSS_MAP32 10 62 #define TCPOLEN_MPTCP_DSS_MAP64 14 63 #define TCPOLEN_MPTCP_DSS_CHECKSUM 2 64 #define TCPOLEN_MPTCP_ADD_ADDR 16 65 #define TCPOLEN_MPTCP_ADD_ADDR_PORT 18 66 #define TCPOLEN_MPTCP_ADD_ADDR_BASE 8 67 #define TCPOLEN_MPTCP_ADD_ADDR_BASE_PORT 10 68 #define TCPOLEN_MPTCP_ADD_ADDR6 28 69 #define TCPOLEN_MPTCP_ADD_ADDR6_PORT 30 70 #define TCPOLEN_MPTCP_ADD_ADDR6_BASE 20 71 #define TCPOLEN_MPTCP_ADD_ADDR6_BASE_PORT 22 72 #define TCPOLEN_MPTCP_PORT_LEN 2 73 #define TCPOLEN_MPTCP_PORT_ALIGN 2 74 #define TCPOLEN_MPTCP_RM_ADDR_BASE 3 75 #define TCPOLEN_MPTCP_PRIO 3 76 #define TCPOLEN_MPTCP_PRIO_ALIGN 4 77 #define TCPOLEN_MPTCP_FASTCLOSE 12 78 #define TCPOLEN_MPTCP_RST 4 79 #define TCPOLEN_MPTCP_FAIL 12 80 81 #define TCPOLEN_MPTCP_MPC_ACK_DATA_CSUM (TCPOLEN_MPTCP_DSS_CHECKSUM + TCPOLEN_MPTCP_MPC_ACK_DATA) 82 83 /* MPTCP MP_JOIN flags */ 84 #define MPTCPOPT_BACKUP BIT(0) 85 #define MPTCPOPT_HMAC_LEN 20 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 flags */ 114 #define MPTCP_DATA_READY 0 115 #define MPTCP_NOSPACE 1 116 #define MPTCP_WORK_RTX 2 117 #define MPTCP_WORK_EOF 3 118 #define MPTCP_FALLBACK_DONE 4 119 #define MPTCP_WORK_CLOSE_SUBFLOW 5 120 #define MPTCP_PUSH_PENDING 6 121 #define MPTCP_CLEAN_UNA 7 122 #define MPTCP_ERROR_REPORT 8 123 #define MPTCP_RETRANSMIT 9 124 #define MPTCP_WORK_SYNC_SETSOCKOPT 10 125 #define MPTCP_CONNECTED 11 126 127 static inline bool before64(__u64 seq1, __u64 seq2) 128 { 129 return (__s64)(seq1 - seq2) < 0; 130 } 131 132 #define after64(seq2, seq1) before64(seq1, seq2) 133 134 struct mptcp_options_received { 135 u64 sndr_key; 136 u64 rcvr_key; 137 u64 data_ack; 138 u64 data_seq; 139 u32 subflow_seq; 140 u16 data_len; 141 __sum16 csum; 142 u16 suboptions; 143 u32 token; 144 u32 nonce; 145 u16 use_map:1, 146 dsn64:1, 147 data_fin:1, 148 use_ack:1, 149 ack64:1, 150 mpc_map:1, 151 reset_reason:4, 152 reset_transient:1, 153 echo:1, 154 backup:1, 155 deny_join_id0:1, 156 __unused:2; 157 u8 join_id; 158 u64 thmac; 159 u8 hmac[MPTCPOPT_HMAC_LEN]; 160 struct mptcp_addr_info addr; 161 struct mptcp_rm_list rm_list; 162 u64 ahmac; 163 u64 fail_seq; 164 }; 165 166 static inline __be32 mptcp_option(u8 subopt, u8 len, u8 nib, u8 field) 167 { 168 return htonl((TCPOPT_MPTCP << 24) | (len << 16) | (subopt << 12) | 169 ((nib & 0xF) << 8) | field); 170 } 171 172 enum mptcp_pm_status { 173 MPTCP_PM_ADD_ADDR_RECEIVED, 174 MPTCP_PM_ADD_ADDR_SEND_ACK, 175 MPTCP_PM_RM_ADDR_RECEIVED, 176 MPTCP_PM_ESTABLISHED, 177 MPTCP_PM_ALREADY_ESTABLISHED, /* persistent status, set after ESTABLISHED event */ 178 MPTCP_PM_SUBFLOW_ESTABLISHED, 179 }; 180 181 enum mptcp_addr_signal_status { 182 MPTCP_ADD_ADDR_SIGNAL, 183 MPTCP_ADD_ADDR_ECHO, 184 MPTCP_RM_ADDR_SIGNAL, 185 }; 186 187 struct mptcp_pm_data { 188 struct mptcp_addr_info local; 189 struct mptcp_addr_info remote; 190 struct list_head anno_list; 191 192 spinlock_t lock; /*protects the whole PM data */ 193 194 u8 addr_signal; 195 bool server_side; 196 bool work_pending; 197 bool accept_addr; 198 bool accept_subflow; 199 bool remote_deny_join_id0; 200 u8 add_addr_signaled; 201 u8 add_addr_accepted; 202 u8 local_addr_used; 203 u8 subflows; 204 u8 status; 205 struct mptcp_rm_list rm_list_tx; 206 struct mptcp_rm_list rm_list_rx; 207 }; 208 209 struct mptcp_data_frag { 210 struct list_head list; 211 u64 data_seq; 212 u16 data_len; 213 u16 offset; 214 u16 overhead; 215 u16 already_sent; 216 struct page *page; 217 }; 218 219 /* MPTCP connection sock */ 220 struct mptcp_sock { 221 /* inet_connection_sock must be the first member */ 222 struct inet_connection_sock sk; 223 u64 local_key; 224 u64 remote_key; 225 u64 write_seq; 226 u64 snd_nxt; 227 u64 ack_seq; 228 u64 rcv_wnd_sent; 229 u64 rcv_data_fin_seq; 230 int wmem_reserved; 231 struct sock *last_snd; 232 int snd_burst; 233 int old_wspace; 234 u64 recovery_snd_nxt; /* in recovery mode accept up to this seq; 235 * recovery related fields are under data_lock 236 * protection 237 */ 238 u64 snd_una; 239 u64 wnd_end; 240 unsigned long timer_ival; 241 u32 token; 242 int rmem_released; 243 unsigned long flags; 244 bool recovery; /* closing subflow write queue reinjected */ 245 bool can_ack; 246 bool fully_established; 247 bool rcv_data_fin; 248 bool snd_data_fin_enable; 249 bool rcv_fastclose; 250 bool use_64bit_ack; /* Set when we received a 64-bit DSN */ 251 bool csum_enabled; 252 spinlock_t join_list_lock; 253 struct work_struct work; 254 struct sk_buff *ooo_last_skb; 255 struct rb_root out_of_order_queue; 256 struct sk_buff_head receive_queue; 257 int tx_pending_data; 258 struct list_head conn_list; 259 struct list_head rtx_queue; 260 struct mptcp_data_frag *first_pending; 261 struct list_head join_list; 262 struct socket *subflow; /* outgoing connect/listener/!mp_capable */ 263 struct sock *first; 264 struct mptcp_pm_data pm; 265 struct { 266 u32 space; /* bytes copied in last measurement window */ 267 u32 copied; /* bytes copied in this measurement window */ 268 u64 time; /* start time of measurement window */ 269 u64 rtt_us; /* last maximum rtt of subflows */ 270 } rcvq_space; 271 272 u32 setsockopt_seq; 273 char ca_name[TCP_CA_NAME_MAX]; 274 }; 275 276 #define mptcp_lock_sock(___sk, cb) do { \ 277 struct sock *__sk = (___sk); /* silence macro reuse warning */ \ 278 might_sleep(); \ 279 spin_lock_bh(&__sk->sk_lock.slock); \ 280 if (__sk->sk_lock.owned) \ 281 __lock_sock(__sk); \ 282 cb; \ 283 __sk->sk_lock.owned = 1; \ 284 spin_unlock(&__sk->sk_lock.slock); \ 285 mutex_acquire(&__sk->sk_lock.dep_map, 0, 0, _RET_IP_); \ 286 local_bh_enable(); \ 287 } while (0) 288 289 #define mptcp_data_lock(sk) spin_lock_bh(&(sk)->sk_lock.slock) 290 #define mptcp_data_unlock(sk) spin_unlock_bh(&(sk)->sk_lock.slock) 291 292 #define mptcp_for_each_subflow(__msk, __subflow) \ 293 list_for_each_entry(__subflow, &((__msk)->conn_list), node) 294 295 static inline void msk_owned_by_me(const struct mptcp_sock *msk) 296 { 297 sock_owned_by_me((const struct sock *)msk); 298 } 299 300 static inline struct mptcp_sock *mptcp_sk(const struct sock *sk) 301 { 302 return (struct mptcp_sock *)sk; 303 } 304 305 /* the msk socket don't use the backlog, also account for the bulk 306 * free memory 307 */ 308 static inline int __mptcp_rmem(const struct sock *sk) 309 { 310 return atomic_read(&sk->sk_rmem_alloc) - READ_ONCE(mptcp_sk(sk)->rmem_released); 311 } 312 313 static inline int __mptcp_space(const struct sock *sk) 314 { 315 return tcp_win_from_space(sk, READ_ONCE(sk->sk_rcvbuf) - __mptcp_rmem(sk)); 316 } 317 318 static inline struct mptcp_data_frag *mptcp_send_head(const struct sock *sk) 319 { 320 const struct mptcp_sock *msk = mptcp_sk(sk); 321 322 return READ_ONCE(msk->first_pending); 323 } 324 325 static inline struct mptcp_data_frag *mptcp_send_next(struct sock *sk) 326 { 327 struct mptcp_sock *msk = mptcp_sk(sk); 328 struct mptcp_data_frag *cur; 329 330 cur = msk->first_pending; 331 return list_is_last(&cur->list, &msk->rtx_queue) ? NULL : 332 list_next_entry(cur, list); 333 } 334 335 static inline struct mptcp_data_frag *mptcp_pending_tail(const struct sock *sk) 336 { 337 struct mptcp_sock *msk = mptcp_sk(sk); 338 339 if (!msk->first_pending) 340 return NULL; 341 342 if (WARN_ON_ONCE(list_empty(&msk->rtx_queue))) 343 return NULL; 344 345 return list_last_entry(&msk->rtx_queue, struct mptcp_data_frag, list); 346 } 347 348 static inline struct mptcp_data_frag *mptcp_rtx_head(const struct sock *sk) 349 { 350 struct mptcp_sock *msk = mptcp_sk(sk); 351 352 if (msk->snd_una == READ_ONCE(msk->snd_nxt)) 353 return NULL; 354 355 return list_first_entry_or_null(&msk->rtx_queue, struct mptcp_data_frag, list); 356 } 357 358 struct csum_pseudo_header { 359 __be64 data_seq; 360 __be32 subflow_seq; 361 __be16 data_len; 362 __sum16 csum; 363 }; 364 365 struct mptcp_subflow_request_sock { 366 struct tcp_request_sock sk; 367 u16 mp_capable : 1, 368 mp_join : 1, 369 backup : 1, 370 csum_reqd : 1, 371 allow_join_id0 : 1; 372 u8 local_id; 373 u8 remote_id; 374 u64 local_key; 375 u64 idsn; 376 u32 token; 377 u32 ssn_offset; 378 u64 thmac; 379 u32 local_nonce; 380 u32 remote_nonce; 381 struct mptcp_sock *msk; 382 struct hlist_nulls_node token_node; 383 }; 384 385 static inline struct mptcp_subflow_request_sock * 386 mptcp_subflow_rsk(const struct request_sock *rsk) 387 { 388 return (struct mptcp_subflow_request_sock *)rsk; 389 } 390 391 enum mptcp_data_avail { 392 MPTCP_SUBFLOW_NODATA, 393 MPTCP_SUBFLOW_DATA_AVAIL, 394 }; 395 396 struct mptcp_delegated_action { 397 struct napi_struct napi; 398 struct list_head head; 399 }; 400 401 DECLARE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions); 402 403 #define MPTCP_DELEGATE_SEND 0 404 405 /* MPTCP subflow context */ 406 struct mptcp_subflow_context { 407 struct list_head node;/* conn_list of subflows */ 408 u64 local_key; 409 u64 remote_key; 410 u64 idsn; 411 u64 map_seq; 412 u32 snd_isn; 413 u32 token; 414 u32 rel_write_seq; 415 u32 map_subflow_seq; 416 u32 ssn_offset; 417 u32 map_data_len; 418 __wsum map_data_csum; 419 u32 map_csum_len; 420 u32 request_mptcp : 1, /* send MP_CAPABLE */ 421 request_join : 1, /* send MP_JOIN */ 422 request_bkup : 1, 423 mp_capable : 1, /* remote is MPTCP capable */ 424 mp_join : 1, /* remote is JOINing */ 425 fully_established : 1, /* path validated */ 426 pm_notified : 1, /* PM hook called for established status */ 427 conn_finished : 1, 428 map_valid : 1, 429 map_csum_reqd : 1, 430 map_data_fin : 1, 431 mpc_map : 1, 432 backup : 1, 433 send_mp_prio : 1, 434 send_mp_fail : 1, 435 rx_eof : 1, 436 can_ack : 1, /* only after processing the remote a key */ 437 disposable : 1, /* ctx can be free at ulp release time */ 438 stale : 1; /* unable to snd/rcv data, do not use for xmit */ 439 enum mptcp_data_avail data_avail; 440 u32 remote_nonce; 441 u64 thmac; 442 u32 local_nonce; 443 u32 remote_token; 444 u8 hmac[MPTCPOPT_HMAC_LEN]; 445 u8 local_id; 446 u8 remote_id; 447 u8 reset_seen:1; 448 u8 reset_transient:1; 449 u8 reset_reason:4; 450 u8 stale_count; 451 452 long delegated_status; 453 struct list_head delegated_node; /* link into delegated_action, protected by local BH */ 454 455 u32 setsockopt_seq; 456 u32 stale_rcv_tstamp; 457 458 struct sock *tcp_sock; /* tcp sk backpointer */ 459 struct sock *conn; /* parent mptcp_sock */ 460 const struct inet_connection_sock_af_ops *icsk_af_ops; 461 void (*tcp_data_ready)(struct sock *sk); 462 void (*tcp_state_change)(struct sock *sk); 463 void (*tcp_write_space)(struct sock *sk); 464 void (*tcp_error_report)(struct sock *sk); 465 466 struct rcu_head rcu; 467 }; 468 469 static inline struct mptcp_subflow_context * 470 mptcp_subflow_ctx(const struct sock *sk) 471 { 472 struct inet_connection_sock *icsk = inet_csk(sk); 473 474 /* Use RCU on icsk_ulp_data only for sock diag code */ 475 return (__force struct mptcp_subflow_context *)icsk->icsk_ulp_data; 476 } 477 478 static inline struct sock * 479 mptcp_subflow_tcp_sock(const struct mptcp_subflow_context *subflow) 480 { 481 return subflow->tcp_sock; 482 } 483 484 static inline u64 485 mptcp_subflow_get_map_offset(const struct mptcp_subflow_context *subflow) 486 { 487 return tcp_sk(mptcp_subflow_tcp_sock(subflow))->copied_seq - 488 subflow->ssn_offset - 489 subflow->map_subflow_seq; 490 } 491 492 static inline u64 493 mptcp_subflow_get_mapped_dsn(const struct mptcp_subflow_context *subflow) 494 { 495 return subflow->map_seq + mptcp_subflow_get_map_offset(subflow); 496 } 497 498 static inline void mptcp_add_pending_subflow(struct mptcp_sock *msk, 499 struct mptcp_subflow_context *subflow) 500 { 501 sock_hold(mptcp_subflow_tcp_sock(subflow)); 502 spin_lock_bh(&msk->join_list_lock); 503 list_add_tail(&subflow->node, &msk->join_list); 504 spin_unlock_bh(&msk->join_list_lock); 505 } 506 507 void mptcp_subflow_process_delegated(struct sock *ssk); 508 509 static inline void mptcp_subflow_delegate(struct mptcp_subflow_context *subflow) 510 { 511 struct mptcp_delegated_action *delegated; 512 bool schedule; 513 514 /* The implied barrier pairs with mptcp_subflow_delegated_done(), and 515 * ensures the below list check sees list updates done prior to status 516 * bit changes 517 */ 518 if (!test_and_set_bit(MPTCP_DELEGATE_SEND, &subflow->delegated_status)) { 519 /* still on delegated list from previous scheduling */ 520 if (!list_empty(&subflow->delegated_node)) 521 return; 522 523 /* the caller held the subflow bh socket lock */ 524 lockdep_assert_in_softirq(); 525 526 delegated = this_cpu_ptr(&mptcp_delegated_actions); 527 schedule = list_empty(&delegated->head); 528 list_add_tail(&subflow->delegated_node, &delegated->head); 529 sock_hold(mptcp_subflow_tcp_sock(subflow)); 530 if (schedule) 531 napi_schedule(&delegated->napi); 532 } 533 } 534 535 static inline struct mptcp_subflow_context * 536 mptcp_subflow_delegated_next(struct mptcp_delegated_action *delegated) 537 { 538 struct mptcp_subflow_context *ret; 539 540 if (list_empty(&delegated->head)) 541 return NULL; 542 543 ret = list_first_entry(&delegated->head, struct mptcp_subflow_context, delegated_node); 544 list_del_init(&ret->delegated_node); 545 return ret; 546 } 547 548 static inline bool mptcp_subflow_has_delegated_action(const struct mptcp_subflow_context *subflow) 549 { 550 return test_bit(MPTCP_DELEGATE_SEND, &subflow->delegated_status); 551 } 552 553 static inline void mptcp_subflow_delegated_done(struct mptcp_subflow_context *subflow) 554 { 555 /* pairs with mptcp_subflow_delegate, ensures delegate_node is updated before 556 * touching the status bit 557 */ 558 smp_wmb(); 559 clear_bit(MPTCP_DELEGATE_SEND, &subflow->delegated_status); 560 } 561 562 int mptcp_is_enabled(const struct net *net); 563 unsigned int mptcp_get_add_addr_timeout(const struct net *net); 564 int mptcp_is_checksum_enabled(const struct net *net); 565 int mptcp_allow_join_id0(const struct net *net); 566 unsigned int mptcp_stale_loss_cnt(const struct net *net); 567 void mptcp_subflow_fully_established(struct mptcp_subflow_context *subflow, 568 struct mptcp_options_received *mp_opt); 569 bool __mptcp_retransmit_pending_data(struct sock *sk); 570 void __mptcp_push_pending(struct sock *sk, unsigned int flags); 571 bool mptcp_subflow_data_available(struct sock *sk); 572 void __init mptcp_subflow_init(void); 573 void mptcp_subflow_shutdown(struct sock *sk, struct sock *ssk, int how); 574 void mptcp_close_ssk(struct sock *sk, struct sock *ssk, 575 struct mptcp_subflow_context *subflow); 576 void mptcp_subflow_send_ack(struct sock *ssk); 577 void mptcp_subflow_reset(struct sock *ssk); 578 void mptcp_sock_graft(struct sock *sk, struct socket *parent); 579 struct socket *__mptcp_nmpc_socket(const struct mptcp_sock *msk); 580 581 /* called with sk socket lock held */ 582 int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_addr_info *loc, 583 const struct mptcp_addr_info *remote); 584 int mptcp_subflow_create_socket(struct sock *sk, struct socket **new_sock); 585 void mptcp_info2sockaddr(const struct mptcp_addr_info *info, 586 struct sockaddr_storage *addr, 587 unsigned short family); 588 589 static inline bool __mptcp_subflow_active(struct mptcp_subflow_context *subflow) 590 { 591 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 592 593 /* can't send if JOIN hasn't completed yet (i.e. is usable for mptcp) */ 594 if (subflow->request_join && !subflow->fully_established) 595 return false; 596 597 /* only send if our side has not closed yet */ 598 return ((1 << ssk->sk_state) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)); 599 } 600 601 void mptcp_subflow_set_active(struct mptcp_subflow_context *subflow); 602 603 bool mptcp_subflow_active(struct mptcp_subflow_context *subflow); 604 605 static inline void mptcp_subflow_tcp_fallback(struct sock *sk, 606 struct mptcp_subflow_context *ctx) 607 { 608 sk->sk_data_ready = ctx->tcp_data_ready; 609 sk->sk_state_change = ctx->tcp_state_change; 610 sk->sk_write_space = ctx->tcp_write_space; 611 sk->sk_error_report = ctx->tcp_error_report; 612 613 inet_csk(sk)->icsk_af_ops = ctx->icsk_af_ops; 614 } 615 616 static inline bool mptcp_has_another_subflow(struct sock *ssk) 617 { 618 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk), *tmp; 619 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 620 621 mptcp_for_each_subflow(msk, tmp) { 622 if (tmp != subflow) 623 return true; 624 } 625 626 return false; 627 } 628 629 void __init mptcp_proto_init(void); 630 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 631 int __init mptcp_proto_v6_init(void); 632 #endif 633 634 struct sock *mptcp_sk_clone(const struct sock *sk, 635 const struct mptcp_options_received *mp_opt, 636 struct request_sock *req); 637 void mptcp_get_options(const struct sock *sk, 638 const struct sk_buff *skb, 639 struct mptcp_options_received *mp_opt); 640 641 void mptcp_finish_connect(struct sock *sk); 642 void __mptcp_set_connected(struct sock *sk); 643 static inline bool mptcp_is_fully_established(struct sock *sk) 644 { 645 return inet_sk_state_load(sk) == TCP_ESTABLISHED && 646 READ_ONCE(mptcp_sk(sk)->fully_established); 647 } 648 void mptcp_rcv_space_init(struct mptcp_sock *msk, const struct sock *ssk); 649 void mptcp_data_ready(struct sock *sk, struct sock *ssk); 650 bool mptcp_finish_join(struct sock *sk); 651 bool mptcp_schedule_work(struct sock *sk); 652 int mptcp_setsockopt(struct sock *sk, int level, int optname, 653 sockptr_t optval, unsigned int optlen); 654 int mptcp_getsockopt(struct sock *sk, int level, int optname, 655 char __user *optval, int __user *option); 656 657 u64 __mptcp_expand_seq(u64 old_seq, u64 cur_seq); 658 static inline u64 mptcp_expand_seq(u64 old_seq, u64 cur_seq, bool use_64bit) 659 { 660 if (use_64bit) 661 return cur_seq; 662 663 return __mptcp_expand_seq(old_seq, cur_seq); 664 } 665 void __mptcp_check_push(struct sock *sk, struct sock *ssk); 666 void __mptcp_data_acked(struct sock *sk); 667 void __mptcp_error_report(struct sock *sk); 668 void mptcp_subflow_eof(struct sock *sk); 669 bool mptcp_update_rcv_data_fin(struct mptcp_sock *msk, u64 data_fin_seq, bool use_64bit); 670 void __mptcp_flush_join_list(struct mptcp_sock *msk); 671 static inline bool mptcp_data_fin_enabled(const struct mptcp_sock *msk) 672 { 673 return READ_ONCE(msk->snd_data_fin_enable) && 674 READ_ONCE(msk->write_seq) == READ_ONCE(msk->snd_nxt); 675 } 676 677 static inline bool mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk) 678 { 679 if ((sk->sk_userlocks & SOCK_SNDBUF_LOCK) || ssk->sk_sndbuf <= READ_ONCE(sk->sk_sndbuf)) 680 return false; 681 682 WRITE_ONCE(sk->sk_sndbuf, ssk->sk_sndbuf); 683 return true; 684 } 685 686 static inline void mptcp_write_space(struct sock *sk) 687 { 688 if (sk_stream_is_writeable(sk)) { 689 /* pairs with memory barrier in mptcp_poll */ 690 smp_mb(); 691 if (test_and_clear_bit(MPTCP_NOSPACE, &mptcp_sk(sk)->flags)) 692 sk_stream_write_space(sk); 693 } 694 } 695 696 void mptcp_destroy_common(struct mptcp_sock *msk); 697 698 #define MPTCP_TOKEN_MAX_RETRIES 4 699 700 void __init mptcp_token_init(void); 701 static inline void mptcp_token_init_request(struct request_sock *req) 702 { 703 mptcp_subflow_rsk(req)->token_node.pprev = NULL; 704 } 705 706 int mptcp_token_new_request(struct request_sock *req); 707 void mptcp_token_destroy_request(struct request_sock *req); 708 int mptcp_token_new_connect(struct sock *sk); 709 void mptcp_token_accept(struct mptcp_subflow_request_sock *r, 710 struct mptcp_sock *msk); 711 bool mptcp_token_exists(u32 token); 712 struct mptcp_sock *mptcp_token_get_sock(struct net *net, u32 token); 713 struct mptcp_sock *mptcp_token_iter_next(const struct net *net, long *s_slot, 714 long *s_num); 715 void mptcp_token_destroy(struct mptcp_sock *msk); 716 717 void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn); 718 719 void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u8 *msg, int len, void *hmac); 720 721 void __init mptcp_pm_init(void); 722 void mptcp_pm_data_init(struct mptcp_sock *msk); 723 void mptcp_pm_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); 724 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); 725 void mptcp_pm_new_connection(struct mptcp_sock *msk, const struct sock *ssk, int server_side); 726 void mptcp_pm_fully_established(struct mptcp_sock *msk, const struct sock *ssk, gfp_t gfp); 727 bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk); 728 void mptcp_pm_connection_closed(struct mptcp_sock *msk); 729 void mptcp_pm_subflow_established(struct mptcp_sock *msk); 730 void mptcp_pm_subflow_closed(struct mptcp_sock *msk, u8 id); 731 void mptcp_pm_add_addr_received(struct mptcp_sock *msk, 732 const struct mptcp_addr_info *addr); 733 void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk, 734 struct mptcp_addr_info *addr); 735 void mptcp_pm_add_addr_send_ack(struct mptcp_sock *msk); 736 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk); 737 void mptcp_pm_rm_addr_received(struct mptcp_sock *msk, 738 const struct mptcp_rm_list *rm_list); 739 void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup); 740 int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk, 741 struct mptcp_addr_info *addr, 742 u8 bkup); 743 void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq); 744 void mptcp_pm_free_anno_list(struct mptcp_sock *msk); 745 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk); 746 struct mptcp_pm_add_entry * 747 mptcp_pm_del_add_timer(struct mptcp_sock *msk, 748 struct mptcp_addr_info *addr, bool check_id); 749 struct mptcp_pm_add_entry * 750 mptcp_lookup_anno_list_by_saddr(struct mptcp_sock *msk, 751 struct mptcp_addr_info *addr); 752 int mptcp_pm_get_flags_and_ifindex_by_id(struct net *net, unsigned int id, 753 u8 *flags, int *ifindex); 754 755 int mptcp_pm_announce_addr(struct mptcp_sock *msk, 756 const struct mptcp_addr_info *addr, 757 bool echo); 758 int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); 759 int mptcp_pm_remove_subflow(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); 760 761 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk, 762 const struct sock *ssk, gfp_t gfp); 763 void mptcp_event_addr_announced(const struct mptcp_sock *msk, const struct mptcp_addr_info *info); 764 void mptcp_event_addr_removed(const struct mptcp_sock *msk, u8 id); 765 766 static inline bool mptcp_pm_should_add_signal(struct mptcp_sock *msk) 767 { 768 return READ_ONCE(msk->pm.addr_signal) & 769 (BIT(MPTCP_ADD_ADDR_SIGNAL) | BIT(MPTCP_ADD_ADDR_ECHO)); 770 } 771 772 static inline bool mptcp_pm_should_add_signal_addr(struct mptcp_sock *msk) 773 { 774 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_SIGNAL); 775 } 776 777 static inline bool mptcp_pm_should_add_signal_echo(struct mptcp_sock *msk) 778 { 779 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_ECHO); 780 } 781 782 static inline bool mptcp_pm_should_rm_signal(struct mptcp_sock *msk) 783 { 784 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_RM_ADDR_SIGNAL); 785 } 786 787 static inline unsigned int mptcp_add_addr_len(int family, bool echo, bool port) 788 { 789 u8 len = TCPOLEN_MPTCP_ADD_ADDR_BASE; 790 791 if (family == AF_INET6) 792 len = TCPOLEN_MPTCP_ADD_ADDR6_BASE; 793 if (!echo) 794 len += MPTCPOPT_THMAC_LEN; 795 /* account for 2 trailing 'nop' options */ 796 if (port) 797 len += TCPOLEN_MPTCP_PORT_LEN + TCPOLEN_MPTCP_PORT_ALIGN; 798 799 return len; 800 } 801 802 static inline int mptcp_rm_addr_len(const struct mptcp_rm_list *rm_list) 803 { 804 if (rm_list->nr == 0 || rm_list->nr > MPTCP_RM_IDS_MAX) 805 return -EINVAL; 806 807 return TCPOLEN_MPTCP_RM_ADDR_BASE + roundup(rm_list->nr - 1, 4) + 1; 808 } 809 810 bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, struct sk_buff *skb, 811 unsigned int opt_size, unsigned int remaining, 812 struct mptcp_addr_info *addr, bool *echo, 813 bool *port, bool *drop_other_suboptions); 814 bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining, 815 struct mptcp_rm_list *rm_list); 816 int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc); 817 818 void __init mptcp_pm_nl_init(void); 819 void mptcp_pm_nl_data_init(struct mptcp_sock *msk); 820 void mptcp_pm_nl_work(struct mptcp_sock *msk); 821 void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk, 822 const struct mptcp_rm_list *rm_list); 823 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct sock_common *skc); 824 unsigned int mptcp_pm_get_add_addr_signal_max(struct mptcp_sock *msk); 825 unsigned int mptcp_pm_get_add_addr_accept_max(struct mptcp_sock *msk); 826 unsigned int mptcp_pm_get_subflows_max(struct mptcp_sock *msk); 827 unsigned int mptcp_pm_get_local_addr_max(struct mptcp_sock *msk); 828 829 void mptcp_sockopt_sync(struct mptcp_sock *msk, struct sock *ssk); 830 void mptcp_sockopt_sync_all(struct mptcp_sock *msk); 831 832 static inline struct mptcp_ext *mptcp_get_ext(const struct sk_buff *skb) 833 { 834 return (struct mptcp_ext *)skb_ext_find(skb, SKB_EXT_MPTCP); 835 } 836 837 void mptcp_diag_subflow_init(struct tcp_ulp_ops *ops); 838 839 static inline bool __mptcp_check_fallback(const struct mptcp_sock *msk) 840 { 841 return test_bit(MPTCP_FALLBACK_DONE, &msk->flags); 842 } 843 844 static inline bool mptcp_check_fallback(const struct sock *sk) 845 { 846 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 847 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 848 849 return __mptcp_check_fallback(msk); 850 } 851 852 static inline void __mptcp_do_fallback(struct mptcp_sock *msk) 853 { 854 if (test_bit(MPTCP_FALLBACK_DONE, &msk->flags)) { 855 pr_debug("TCP fallback already done (msk=%p)", msk); 856 return; 857 } 858 set_bit(MPTCP_FALLBACK_DONE, &msk->flags); 859 } 860 861 static inline void mptcp_do_fallback(struct sock *sk) 862 { 863 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 864 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 865 866 __mptcp_do_fallback(msk); 867 } 868 869 #define pr_fallback(a) pr_debug("%s:fallback to TCP (msk=%p)", __func__, a) 870 871 static inline bool subflow_simultaneous_connect(struct sock *sk) 872 { 873 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 874 struct sock *parent = subflow->conn; 875 876 return sk->sk_state == TCP_ESTABLISHED && 877 !mptcp_sk(parent)->pm.server_side && 878 !subflow->conn_finished; 879 } 880 881 #ifdef CONFIG_SYN_COOKIES 882 void subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 883 struct sk_buff *skb); 884 bool mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 885 struct sk_buff *skb); 886 void __init mptcp_join_cookie_init(void); 887 #else 888 static inline void 889 subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 890 struct sk_buff *skb) {} 891 static inline bool 892 mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 893 struct sk_buff *skb) 894 { 895 return false; 896 } 897 898 static inline void mptcp_join_cookie_init(void) {} 899 #endif 900 901 #endif /* __MPTCP_PROTOCOL_H */ 902