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 atomic flags */ 114 #define MPTCP_NOSPACE 1 115 #define MPTCP_WORK_RTX 2 116 #define MPTCP_WORK_EOF 3 117 #define MPTCP_FALLBACK_DONE 4 118 #define MPTCP_WORK_CLOSE_SUBFLOW 5 119 120 /* MPTCP socket release cb flags */ 121 #define MPTCP_PUSH_PENDING 1 122 #define MPTCP_CLEAN_UNA 2 123 #define MPTCP_ERROR_REPORT 3 124 #define MPTCP_RETRANSMIT 4 125 #define MPTCP_FLUSH_JOIN_LIST 5 126 #define MPTCP_CONNECTED 6 127 #define MPTCP_RESET_SCHEDULER 7 128 129 static inline bool before64(__u64 seq1, __u64 seq2) 130 { 131 return (__s64)(seq1 - seq2) < 0; 132 } 133 134 #define after64(seq2, seq1) before64(seq1, seq2) 135 136 struct mptcp_options_received { 137 u64 sndr_key; 138 u64 rcvr_key; 139 u64 data_ack; 140 u64 data_seq; 141 u32 subflow_seq; 142 u16 data_len; 143 __sum16 csum; 144 u16 suboptions; 145 u32 token; 146 u32 nonce; 147 u16 use_map:1, 148 dsn64:1, 149 data_fin:1, 150 use_ack:1, 151 ack64:1, 152 mpc_map:1, 153 reset_reason:4, 154 reset_transient:1, 155 echo:1, 156 backup:1, 157 deny_join_id0:1, 158 __unused:2; 159 u8 join_id; 160 u64 thmac; 161 u8 hmac[MPTCPOPT_HMAC_LEN]; 162 struct mptcp_addr_info addr; 163 struct mptcp_rm_list rm_list; 164 u64 ahmac; 165 u64 fail_seq; 166 }; 167 168 static inline __be32 mptcp_option(u8 subopt, u8 len, u8 nib, u8 field) 169 { 170 return htonl((TCPOPT_MPTCP << 24) | (len << 16) | (subopt << 12) | 171 ((nib & 0xF) << 8) | field); 172 } 173 174 enum mptcp_pm_status { 175 MPTCP_PM_ADD_ADDR_RECEIVED, 176 MPTCP_PM_ADD_ADDR_SEND_ACK, 177 MPTCP_PM_RM_ADDR_RECEIVED, 178 MPTCP_PM_ESTABLISHED, 179 MPTCP_PM_SUBFLOW_ESTABLISHED, 180 MPTCP_PM_ALREADY_ESTABLISHED, /* persistent status, set after ESTABLISHED event */ 181 MPTCP_PM_MPC_ENDPOINT_ACCOUNTED /* persistent status, set after MPC local address is 182 * accounted int id_avail_bitmap 183 */ 184 }; 185 186 /* Status bits below MPTCP_PM_ALREADY_ESTABLISHED need pm worker actions */ 187 #define MPTCP_PM_WORK_MASK ((1 << MPTCP_PM_ALREADY_ESTABLISHED) - 1) 188 189 enum mptcp_addr_signal_status { 190 MPTCP_ADD_ADDR_SIGNAL, 191 MPTCP_ADD_ADDR_ECHO, 192 MPTCP_RM_ADDR_SIGNAL, 193 }; 194 195 /* max value of mptcp_addr_info.id */ 196 #define MPTCP_PM_MAX_ADDR_ID U8_MAX 197 198 struct mptcp_pm_data { 199 struct mptcp_addr_info local; 200 struct mptcp_addr_info remote; 201 struct list_head anno_list; 202 203 spinlock_t lock; /*protects the whole PM data */ 204 205 u8 addr_signal; 206 bool server_side; 207 bool work_pending; 208 bool accept_addr; 209 bool accept_subflow; 210 bool remote_deny_join_id0; 211 u8 add_addr_signaled; 212 u8 add_addr_accepted; 213 u8 local_addr_used; 214 u8 subflows; 215 u8 status; 216 DECLARE_BITMAP(id_avail_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); 217 struct mptcp_rm_list rm_list_tx; 218 struct mptcp_rm_list rm_list_rx; 219 }; 220 221 struct mptcp_data_frag { 222 struct list_head list; 223 u64 data_seq; 224 u16 data_len; 225 u16 offset; 226 u16 overhead; 227 u16 already_sent; 228 struct page *page; 229 }; 230 231 /* MPTCP connection sock */ 232 struct mptcp_sock { 233 /* inet_connection_sock must be the first member */ 234 struct inet_connection_sock sk; 235 u64 local_key; 236 u64 remote_key; 237 u64 write_seq; 238 u64 snd_nxt; 239 u64 ack_seq; 240 u64 rcv_wnd_sent; 241 u64 rcv_data_fin_seq; 242 int rmem_fwd_alloc; 243 struct sock *last_snd; 244 int snd_burst; 245 int old_wspace; 246 u64 recovery_snd_nxt; /* in recovery mode accept up to this seq; 247 * recovery related fields are under data_lock 248 * protection 249 */ 250 u64 snd_una; 251 u64 wnd_end; 252 unsigned long timer_ival; 253 u32 token; 254 int rmem_released; 255 unsigned long flags; 256 unsigned long cb_flags; 257 unsigned long push_pending; 258 bool recovery; /* closing subflow write queue reinjected */ 259 bool can_ack; 260 bool fully_established; 261 bool rcv_data_fin; 262 bool snd_data_fin_enable; 263 bool rcv_fastclose; 264 bool use_64bit_ack; /* Set when we received a 64-bit DSN */ 265 bool csum_enabled; 266 u8 recvmsg_inq:1, 267 cork:1, 268 nodelay:1; 269 struct work_struct work; 270 struct sk_buff *ooo_last_skb; 271 struct rb_root out_of_order_queue; 272 struct sk_buff_head receive_queue; 273 struct list_head conn_list; 274 struct list_head rtx_queue; 275 struct mptcp_data_frag *first_pending; 276 struct list_head join_list; 277 struct socket *subflow; /* outgoing connect/listener/!mp_capable */ 278 struct sock *first; 279 struct mptcp_pm_data pm; 280 struct { 281 u32 space; /* bytes copied in last measurement window */ 282 u32 copied; /* bytes copied in this measurement window */ 283 u64 time; /* start time of measurement window */ 284 u64 rtt_us; /* last maximum rtt of subflows */ 285 } rcvq_space; 286 287 u32 setsockopt_seq; 288 char ca_name[TCP_CA_NAME_MAX]; 289 }; 290 291 #define mptcp_data_lock(sk) spin_lock_bh(&(sk)->sk_lock.slock) 292 #define mptcp_data_unlock(sk) spin_unlock_bh(&(sk)->sk_lock.slock) 293 294 #define mptcp_for_each_subflow(__msk, __subflow) \ 295 list_for_each_entry(__subflow, &((__msk)->conn_list), node) 296 297 static inline void msk_owned_by_me(const struct mptcp_sock *msk) 298 { 299 sock_owned_by_me((const struct sock *)msk); 300 } 301 302 static inline struct mptcp_sock *mptcp_sk(const struct sock *sk) 303 { 304 return (struct mptcp_sock *)sk; 305 } 306 307 /* the msk socket don't use the backlog, also account for the bulk 308 * free memory 309 */ 310 static inline int __mptcp_rmem(const struct sock *sk) 311 { 312 return atomic_read(&sk->sk_rmem_alloc) - READ_ONCE(mptcp_sk(sk)->rmem_released); 313 } 314 315 static inline int __mptcp_space(const struct sock *sk) 316 { 317 return tcp_win_from_space(sk, READ_ONCE(sk->sk_rcvbuf) - __mptcp_rmem(sk)); 318 } 319 320 static inline struct mptcp_data_frag *mptcp_send_head(const struct sock *sk) 321 { 322 const struct mptcp_sock *msk = mptcp_sk(sk); 323 324 return READ_ONCE(msk->first_pending); 325 } 326 327 static inline struct mptcp_data_frag *mptcp_send_next(struct sock *sk) 328 { 329 struct mptcp_sock *msk = mptcp_sk(sk); 330 struct mptcp_data_frag *cur; 331 332 cur = msk->first_pending; 333 return list_is_last(&cur->list, &msk->rtx_queue) ? NULL : 334 list_next_entry(cur, list); 335 } 336 337 static inline struct mptcp_data_frag *mptcp_pending_tail(const struct sock *sk) 338 { 339 struct mptcp_sock *msk = mptcp_sk(sk); 340 341 if (!msk->first_pending) 342 return NULL; 343 344 if (WARN_ON_ONCE(list_empty(&msk->rtx_queue))) 345 return NULL; 346 347 return list_last_entry(&msk->rtx_queue, struct mptcp_data_frag, list); 348 } 349 350 static inline struct mptcp_data_frag *mptcp_rtx_head(const struct sock *sk) 351 { 352 struct mptcp_sock *msk = mptcp_sk(sk); 353 354 if (msk->snd_una == READ_ONCE(msk->snd_nxt)) 355 return NULL; 356 357 return list_first_entry_or_null(&msk->rtx_queue, struct mptcp_data_frag, list); 358 } 359 360 struct csum_pseudo_header { 361 __be64 data_seq; 362 __be32 subflow_seq; 363 __be16 data_len; 364 __sum16 csum; 365 }; 366 367 struct mptcp_subflow_request_sock { 368 struct tcp_request_sock sk; 369 u16 mp_capable : 1, 370 mp_join : 1, 371 backup : 1, 372 csum_reqd : 1, 373 allow_join_id0 : 1; 374 u8 local_id; 375 u8 remote_id; 376 u64 local_key; 377 u64 idsn; 378 u32 token; 379 u32 ssn_offset; 380 u64 thmac; 381 u32 local_nonce; 382 u32 remote_nonce; 383 struct mptcp_sock *msk; 384 struct hlist_nulls_node token_node; 385 }; 386 387 static inline struct mptcp_subflow_request_sock * 388 mptcp_subflow_rsk(const struct request_sock *rsk) 389 { 390 return (struct mptcp_subflow_request_sock *)rsk; 391 } 392 393 enum mptcp_data_avail { 394 MPTCP_SUBFLOW_NODATA, 395 MPTCP_SUBFLOW_DATA_AVAIL, 396 }; 397 398 struct mptcp_delegated_action { 399 struct napi_struct napi; 400 struct list_head head; 401 }; 402 403 DECLARE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions); 404 405 #define MPTCP_DELEGATE_SEND 0 406 #define MPTCP_DELEGATE_ACK 1 407 408 /* MPTCP subflow context */ 409 struct mptcp_subflow_context { 410 struct list_head node;/* conn_list of subflows */ 411 412 struct_group(reset, 413 414 unsigned long avg_pacing_rate; /* protected by msk socket lock */ 415 u64 local_key; 416 u64 remote_key; 417 u64 idsn; 418 u64 map_seq; 419 u32 snd_isn; 420 u32 token; 421 u32 rel_write_seq; 422 u32 map_subflow_seq; 423 u32 ssn_offset; 424 u32 map_data_len; 425 __wsum map_data_csum; 426 u32 map_csum_len; 427 u32 request_mptcp : 1, /* send MP_CAPABLE */ 428 request_join : 1, /* send MP_JOIN */ 429 request_bkup : 1, 430 mp_capable : 1, /* remote is MPTCP capable */ 431 mp_join : 1, /* remote is JOINing */ 432 fully_established : 1, /* path validated */ 433 pm_notified : 1, /* PM hook called for established status */ 434 conn_finished : 1, 435 map_valid : 1, 436 map_csum_reqd : 1, 437 map_data_fin : 1, 438 mpc_map : 1, 439 backup : 1, 440 send_mp_prio : 1, 441 send_mp_fail : 1, 442 send_fastclose : 1, 443 rx_eof : 1, 444 can_ack : 1, /* only after processing the remote a key */ 445 disposable : 1, /* ctx can be free at ulp release time */ 446 stale : 1, /* unable to snd/rcv data, do not use for xmit */ 447 local_id_valid : 1; /* local_id is correctly initialized */ 448 enum mptcp_data_avail data_avail; 449 u32 remote_nonce; 450 u64 thmac; 451 u32 local_nonce; 452 u32 remote_token; 453 u8 hmac[MPTCPOPT_HMAC_LEN]; 454 u8 local_id; 455 u8 remote_id; 456 u8 reset_seen:1; 457 u8 reset_transient:1; 458 u8 reset_reason:4; 459 u8 stale_count; 460 461 long delegated_status; 462 463 ); 464 465 struct list_head delegated_node; /* link into delegated_action, protected by local BH */ 466 467 u32 setsockopt_seq; 468 u32 stale_rcv_tstamp; 469 470 struct sock *tcp_sock; /* tcp sk backpointer */ 471 struct sock *conn; /* parent mptcp_sock */ 472 const struct inet_connection_sock_af_ops *icsk_af_ops; 473 void (*tcp_state_change)(struct sock *sk); 474 void (*tcp_error_report)(struct sock *sk); 475 476 struct rcu_head rcu; 477 }; 478 479 static inline struct mptcp_subflow_context * 480 mptcp_subflow_ctx(const struct sock *sk) 481 { 482 struct inet_connection_sock *icsk = inet_csk(sk); 483 484 /* Use RCU on icsk_ulp_data only for sock diag code */ 485 return (__force struct mptcp_subflow_context *)icsk->icsk_ulp_data; 486 } 487 488 static inline struct sock * 489 mptcp_subflow_tcp_sock(const struct mptcp_subflow_context *subflow) 490 { 491 return subflow->tcp_sock; 492 } 493 494 static inline void 495 mptcp_subflow_ctx_reset(struct mptcp_subflow_context *subflow) 496 { 497 memset(&subflow->reset, 0, sizeof(subflow->reset)); 498 subflow->request_mptcp = 1; 499 } 500 501 static inline u64 502 mptcp_subflow_get_map_offset(const struct mptcp_subflow_context *subflow) 503 { 504 return tcp_sk(mptcp_subflow_tcp_sock(subflow))->copied_seq - 505 subflow->ssn_offset - 506 subflow->map_subflow_seq; 507 } 508 509 static inline u64 510 mptcp_subflow_get_mapped_dsn(const struct mptcp_subflow_context *subflow) 511 { 512 return subflow->map_seq + mptcp_subflow_get_map_offset(subflow); 513 } 514 515 void mptcp_subflow_process_delegated(struct sock *ssk); 516 517 static inline void mptcp_subflow_delegate(struct mptcp_subflow_context *subflow, int action) 518 { 519 struct mptcp_delegated_action *delegated; 520 bool schedule; 521 522 /* the caller held the subflow bh socket lock */ 523 lockdep_assert_in_softirq(); 524 525 /* The implied barrier pairs with mptcp_subflow_delegated_done(), and 526 * ensures the below list check sees list updates done prior to status 527 * bit changes 528 */ 529 if (!test_and_set_bit(action, &subflow->delegated_status)) { 530 /* still on delegated list from previous scheduling */ 531 if (!list_empty(&subflow->delegated_node)) 532 return; 533 534 delegated = this_cpu_ptr(&mptcp_delegated_actions); 535 schedule = list_empty(&delegated->head); 536 list_add_tail(&subflow->delegated_node, &delegated->head); 537 sock_hold(mptcp_subflow_tcp_sock(subflow)); 538 if (schedule) 539 napi_schedule(&delegated->napi); 540 } 541 } 542 543 static inline struct mptcp_subflow_context * 544 mptcp_subflow_delegated_next(struct mptcp_delegated_action *delegated) 545 { 546 struct mptcp_subflow_context *ret; 547 548 if (list_empty(&delegated->head)) 549 return NULL; 550 551 ret = list_first_entry(&delegated->head, struct mptcp_subflow_context, delegated_node); 552 list_del_init(&ret->delegated_node); 553 return ret; 554 } 555 556 static inline bool mptcp_subflow_has_delegated_action(const struct mptcp_subflow_context *subflow) 557 { 558 return !!READ_ONCE(subflow->delegated_status); 559 } 560 561 static inline void mptcp_subflow_delegated_done(struct mptcp_subflow_context *subflow, int action) 562 { 563 /* pairs with mptcp_subflow_delegate, ensures delegate_node is updated before 564 * touching the status bit 565 */ 566 smp_wmb(); 567 clear_bit(action, &subflow->delegated_status); 568 } 569 570 int mptcp_is_enabled(const struct net *net); 571 unsigned int mptcp_get_add_addr_timeout(const struct net *net); 572 int mptcp_is_checksum_enabled(const struct net *net); 573 int mptcp_allow_join_id0(const struct net *net); 574 unsigned int mptcp_stale_loss_cnt(const struct net *net); 575 void mptcp_subflow_fully_established(struct mptcp_subflow_context *subflow, 576 struct mptcp_options_received *mp_opt); 577 bool __mptcp_retransmit_pending_data(struct sock *sk); 578 void mptcp_check_and_set_pending(struct sock *sk); 579 void __mptcp_push_pending(struct sock *sk, unsigned int flags); 580 bool mptcp_subflow_data_available(struct sock *sk); 581 void __init mptcp_subflow_init(void); 582 void mptcp_subflow_shutdown(struct sock *sk, struct sock *ssk, int how); 583 void mptcp_close_ssk(struct sock *sk, struct sock *ssk, 584 struct mptcp_subflow_context *subflow); 585 void mptcp_subflow_send_ack(struct sock *ssk); 586 void mptcp_subflow_reset(struct sock *ssk); 587 void mptcp_sock_graft(struct sock *sk, struct socket *parent); 588 struct socket *__mptcp_nmpc_socket(const struct mptcp_sock *msk); 589 590 /* called with sk socket lock held */ 591 int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_addr_info *loc, 592 const struct mptcp_addr_info *remote); 593 int mptcp_subflow_create_socket(struct sock *sk, struct socket **new_sock); 594 void mptcp_info2sockaddr(const struct mptcp_addr_info *info, 595 struct sockaddr_storage *addr, 596 unsigned short family); 597 598 static inline bool __mptcp_subflow_active(struct mptcp_subflow_context *subflow) 599 { 600 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 601 602 /* can't send if JOIN hasn't completed yet (i.e. is usable for mptcp) */ 603 if (subflow->request_join && !subflow->fully_established) 604 return false; 605 606 /* only send if our side has not closed yet */ 607 return ((1 << ssk->sk_state) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)); 608 } 609 610 void mptcp_subflow_set_active(struct mptcp_subflow_context *subflow); 611 612 bool mptcp_subflow_active(struct mptcp_subflow_context *subflow); 613 614 static inline void mptcp_subflow_tcp_fallback(struct sock *sk, 615 struct mptcp_subflow_context *ctx) 616 { 617 sk->sk_data_ready = sock_def_readable; 618 sk->sk_state_change = ctx->tcp_state_change; 619 sk->sk_write_space = sk_stream_write_space; 620 sk->sk_error_report = ctx->tcp_error_report; 621 622 inet_csk(sk)->icsk_af_ops = ctx->icsk_af_ops; 623 } 624 625 static inline bool mptcp_has_another_subflow(struct sock *ssk) 626 { 627 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk), *tmp; 628 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 629 630 mptcp_for_each_subflow(msk, tmp) { 631 if (tmp != subflow) 632 return true; 633 } 634 635 return false; 636 } 637 638 void __init mptcp_proto_init(void); 639 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 640 int __init mptcp_proto_v6_init(void); 641 #endif 642 643 struct sock *mptcp_sk_clone(const struct sock *sk, 644 const struct mptcp_options_received *mp_opt, 645 struct request_sock *req); 646 void mptcp_get_options(const struct sk_buff *skb, 647 struct mptcp_options_received *mp_opt); 648 649 void mptcp_finish_connect(struct sock *sk); 650 void __mptcp_set_connected(struct sock *sk); 651 static inline bool mptcp_is_fully_established(struct sock *sk) 652 { 653 return inet_sk_state_load(sk) == TCP_ESTABLISHED && 654 READ_ONCE(mptcp_sk(sk)->fully_established); 655 } 656 void mptcp_rcv_space_init(struct mptcp_sock *msk, const struct sock *ssk); 657 void mptcp_data_ready(struct sock *sk, struct sock *ssk); 658 bool mptcp_finish_join(struct sock *sk); 659 bool mptcp_schedule_work(struct sock *sk); 660 int mptcp_setsockopt(struct sock *sk, int level, int optname, 661 sockptr_t optval, unsigned int optlen); 662 int mptcp_getsockopt(struct sock *sk, int level, int optname, 663 char __user *optval, int __user *option); 664 665 u64 __mptcp_expand_seq(u64 old_seq, u64 cur_seq); 666 static inline u64 mptcp_expand_seq(u64 old_seq, u64 cur_seq, bool use_64bit) 667 { 668 if (use_64bit) 669 return cur_seq; 670 671 return __mptcp_expand_seq(old_seq, cur_seq); 672 } 673 void __mptcp_check_push(struct sock *sk, struct sock *ssk); 674 void __mptcp_data_acked(struct sock *sk); 675 void __mptcp_error_report(struct sock *sk); 676 void mptcp_subflow_eof(struct sock *sk); 677 bool mptcp_update_rcv_data_fin(struct mptcp_sock *msk, u64 data_fin_seq, bool use_64bit); 678 static inline bool mptcp_data_fin_enabled(const struct mptcp_sock *msk) 679 { 680 return READ_ONCE(msk->snd_data_fin_enable) && 681 READ_ONCE(msk->write_seq) == READ_ONCE(msk->snd_nxt); 682 } 683 684 static inline bool mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk) 685 { 686 if ((sk->sk_userlocks & SOCK_SNDBUF_LOCK) || ssk->sk_sndbuf <= READ_ONCE(sk->sk_sndbuf)) 687 return false; 688 689 WRITE_ONCE(sk->sk_sndbuf, ssk->sk_sndbuf); 690 return true; 691 } 692 693 static inline void mptcp_write_space(struct sock *sk) 694 { 695 if (sk_stream_is_writeable(sk)) { 696 /* pairs with memory barrier in mptcp_poll */ 697 smp_mb(); 698 if (test_and_clear_bit(MPTCP_NOSPACE, &mptcp_sk(sk)->flags)) 699 sk_stream_write_space(sk); 700 } 701 } 702 703 void mptcp_destroy_common(struct mptcp_sock *msk); 704 705 #define MPTCP_TOKEN_MAX_RETRIES 4 706 707 void __init mptcp_token_init(void); 708 static inline void mptcp_token_init_request(struct request_sock *req) 709 { 710 mptcp_subflow_rsk(req)->token_node.pprev = NULL; 711 } 712 713 int mptcp_token_new_request(struct request_sock *req); 714 void mptcp_token_destroy_request(struct request_sock *req); 715 int mptcp_token_new_connect(struct sock *sk); 716 void mptcp_token_accept(struct mptcp_subflow_request_sock *r, 717 struct mptcp_sock *msk); 718 bool mptcp_token_exists(u32 token); 719 struct mptcp_sock *mptcp_token_get_sock(struct net *net, u32 token); 720 struct mptcp_sock *mptcp_token_iter_next(const struct net *net, long *s_slot, 721 long *s_num); 722 void mptcp_token_destroy(struct mptcp_sock *msk); 723 724 void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn); 725 726 void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u8 *msg, int len, void *hmac); 727 u16 __mptcp_make_csum(u64 data_seq, u32 subflow_seq, u16 data_len, __wsum sum); 728 729 void __init mptcp_pm_init(void); 730 void mptcp_pm_data_init(struct mptcp_sock *msk); 731 void mptcp_pm_data_reset(struct mptcp_sock *msk); 732 void mptcp_pm_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); 733 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); 734 void mptcp_pm_new_connection(struct mptcp_sock *msk, const struct sock *ssk, int server_side); 735 void mptcp_pm_fully_established(struct mptcp_sock *msk, const struct sock *ssk, gfp_t gfp); 736 bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk); 737 void mptcp_pm_connection_closed(struct mptcp_sock *msk); 738 void mptcp_pm_subflow_established(struct mptcp_sock *msk); 739 bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk); 740 void mptcp_pm_subflow_check_next(struct mptcp_sock *msk, const struct sock *ssk, 741 const struct mptcp_subflow_context *subflow); 742 void mptcp_pm_add_addr_received(struct mptcp_sock *msk, 743 const struct mptcp_addr_info *addr); 744 void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk, 745 const struct mptcp_addr_info *addr); 746 void mptcp_pm_add_addr_send_ack(struct mptcp_sock *msk); 747 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk); 748 void mptcp_pm_rm_addr_received(struct mptcp_sock *msk, 749 const struct mptcp_rm_list *rm_list); 750 void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup); 751 void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq); 752 void mptcp_pm_free_anno_list(struct mptcp_sock *msk); 753 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk); 754 struct mptcp_pm_add_entry * 755 mptcp_pm_del_add_timer(struct mptcp_sock *msk, 756 const struct mptcp_addr_info *addr, bool check_id); 757 struct mptcp_pm_add_entry * 758 mptcp_lookup_anno_list_by_saddr(const struct mptcp_sock *msk, 759 const struct mptcp_addr_info *addr); 760 int mptcp_pm_get_flags_and_ifindex_by_id(struct net *net, unsigned int id, 761 u8 *flags, int *ifindex); 762 763 int mptcp_pm_announce_addr(struct mptcp_sock *msk, 764 const struct mptcp_addr_info *addr, 765 bool echo); 766 int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); 767 int mptcp_pm_remove_subflow(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); 768 769 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk, 770 const struct sock *ssk, gfp_t gfp); 771 void mptcp_event_addr_announced(const struct mptcp_sock *msk, const struct mptcp_addr_info *info); 772 void mptcp_event_addr_removed(const struct mptcp_sock *msk, u8 id); 773 774 static inline bool mptcp_pm_should_add_signal(struct mptcp_sock *msk) 775 { 776 return READ_ONCE(msk->pm.addr_signal) & 777 (BIT(MPTCP_ADD_ADDR_SIGNAL) | BIT(MPTCP_ADD_ADDR_ECHO)); 778 } 779 780 static inline bool mptcp_pm_should_add_signal_addr(struct mptcp_sock *msk) 781 { 782 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_SIGNAL); 783 } 784 785 static inline bool mptcp_pm_should_add_signal_echo(struct mptcp_sock *msk) 786 { 787 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_ECHO); 788 } 789 790 static inline bool mptcp_pm_should_rm_signal(struct mptcp_sock *msk) 791 { 792 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_RM_ADDR_SIGNAL); 793 } 794 795 static inline unsigned int mptcp_add_addr_len(int family, bool echo, bool port) 796 { 797 u8 len = TCPOLEN_MPTCP_ADD_ADDR_BASE; 798 799 if (family == AF_INET6) 800 len = TCPOLEN_MPTCP_ADD_ADDR6_BASE; 801 if (!echo) 802 len += MPTCPOPT_THMAC_LEN; 803 /* account for 2 trailing 'nop' options */ 804 if (port) 805 len += TCPOLEN_MPTCP_PORT_LEN + TCPOLEN_MPTCP_PORT_ALIGN; 806 807 return len; 808 } 809 810 static inline int mptcp_rm_addr_len(const struct mptcp_rm_list *rm_list) 811 { 812 if (rm_list->nr == 0 || rm_list->nr > MPTCP_RM_IDS_MAX) 813 return -EINVAL; 814 815 return TCPOLEN_MPTCP_RM_ADDR_BASE + roundup(rm_list->nr - 1, 4) + 1; 816 } 817 818 bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, const struct sk_buff *skb, 819 unsigned int opt_size, unsigned int remaining, 820 struct mptcp_addr_info *addr, bool *echo, 821 bool *drop_other_suboptions); 822 bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining, 823 struct mptcp_rm_list *rm_list); 824 int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc); 825 826 void __init mptcp_pm_nl_init(void); 827 void mptcp_pm_nl_data_init(struct mptcp_sock *msk); 828 void mptcp_pm_nl_work(struct mptcp_sock *msk); 829 void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk, 830 const struct mptcp_rm_list *rm_list); 831 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct sock_common *skc); 832 unsigned int mptcp_pm_get_add_addr_signal_max(const struct mptcp_sock *msk); 833 unsigned int mptcp_pm_get_add_addr_accept_max(const struct mptcp_sock *msk); 834 unsigned int mptcp_pm_get_subflows_max(const struct mptcp_sock *msk); 835 unsigned int mptcp_pm_get_local_addr_max(const struct mptcp_sock *msk); 836 837 void mptcp_sockopt_sync(struct mptcp_sock *msk, struct sock *ssk); 838 void mptcp_sockopt_sync_locked(struct mptcp_sock *msk, struct sock *ssk); 839 840 static inline struct mptcp_ext *mptcp_get_ext(const struct sk_buff *skb) 841 { 842 return (struct mptcp_ext *)skb_ext_find(skb, SKB_EXT_MPTCP); 843 } 844 845 void mptcp_diag_subflow_init(struct tcp_ulp_ops *ops); 846 847 static inline bool __mptcp_check_fallback(const struct mptcp_sock *msk) 848 { 849 return test_bit(MPTCP_FALLBACK_DONE, &msk->flags); 850 } 851 852 static inline bool mptcp_check_fallback(const struct sock *sk) 853 { 854 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 855 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 856 857 return __mptcp_check_fallback(msk); 858 } 859 860 static inline void __mptcp_do_fallback(struct mptcp_sock *msk) 861 { 862 if (test_bit(MPTCP_FALLBACK_DONE, &msk->flags)) { 863 pr_debug("TCP fallback already done (msk=%p)", msk); 864 return; 865 } 866 set_bit(MPTCP_FALLBACK_DONE, &msk->flags); 867 } 868 869 static inline void mptcp_do_fallback(struct sock *sk) 870 { 871 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 872 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 873 874 __mptcp_do_fallback(msk); 875 } 876 877 #define pr_fallback(a) pr_debug("%s:fallback to TCP (msk=%p)", __func__, a) 878 879 static inline bool subflow_simultaneous_connect(struct sock *sk) 880 { 881 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 882 struct sock *parent = subflow->conn; 883 884 return sk->sk_state == TCP_ESTABLISHED && 885 !mptcp_sk(parent)->pm.server_side && 886 !subflow->conn_finished; 887 } 888 889 #ifdef CONFIG_SYN_COOKIES 890 void subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 891 struct sk_buff *skb); 892 bool mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 893 struct sk_buff *skb); 894 void __init mptcp_join_cookie_init(void); 895 #else 896 static inline void 897 subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 898 struct sk_buff *skb) {} 899 static inline bool 900 mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 901 struct sk_buff *skb) 902 { 903 return false; 904 } 905 906 static inline void mptcp_join_cookie_init(void) {} 907 #endif 908 909 #endif /* __MPTCP_PROTOCOL_H */ 910