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 6 127 128 static inline bool before64(__u64 seq1, __u64 seq2) 129 { 130 return (__s64)(seq1 - seq2) < 0; 131 } 132 133 #define after64(seq2, seq1) before64(seq1, seq2) 134 135 struct mptcp_options_received { 136 u64 sndr_key; 137 u64 rcvr_key; 138 u64 data_ack; 139 u64 data_seq; 140 u32 subflow_seq; 141 u16 data_len; 142 __sum16 csum; 143 u16 suboptions; 144 u32 token; 145 u32 nonce; 146 u16 use_map:1, 147 dsn64:1, 148 data_fin:1, 149 use_ack:1, 150 ack64:1, 151 mpc_map:1, 152 reset_reason:4, 153 reset_transient:1, 154 echo:1, 155 backup:1, 156 deny_join_id0:1, 157 __unused:2; 158 u8 join_id; 159 u64 thmac; 160 u8 hmac[MPTCPOPT_HMAC_LEN]; 161 struct mptcp_addr_info addr; 162 struct mptcp_rm_list rm_list; 163 u64 ahmac; 164 u64 fail_seq; 165 }; 166 167 static inline __be32 mptcp_option(u8 subopt, u8 len, u8 nib, u8 field) 168 { 169 return htonl((TCPOPT_MPTCP << 24) | (len << 16) | (subopt << 12) | 170 ((nib & 0xF) << 8) | field); 171 } 172 173 enum mptcp_pm_status { 174 MPTCP_PM_ADD_ADDR_RECEIVED, 175 MPTCP_PM_ADD_ADDR_SEND_ACK, 176 MPTCP_PM_RM_ADDR_RECEIVED, 177 MPTCP_PM_ESTABLISHED, 178 MPTCP_PM_SUBFLOW_ESTABLISHED, 179 MPTCP_PM_ALREADY_ESTABLISHED, /* persistent status, set after ESTABLISHED event */ 180 MPTCP_PM_MPC_ENDPOINT_ACCOUNTED /* persistent status, set after MPC local address is 181 * accounted int id_avail_bitmap 182 */ 183 }; 184 185 /* Status bits below MPTCP_PM_ALREADY_ESTABLISHED need pm worker actions */ 186 #define MPTCP_PM_WORK_MASK ((1 << MPTCP_PM_ALREADY_ESTABLISHED) - 1) 187 188 enum mptcp_addr_signal_status { 189 MPTCP_ADD_ADDR_SIGNAL, 190 MPTCP_ADD_ADDR_ECHO, 191 MPTCP_RM_ADDR_SIGNAL, 192 }; 193 194 /* max value of mptcp_addr_info.id */ 195 #define MPTCP_PM_MAX_ADDR_ID U8_MAX 196 197 struct mptcp_pm_data { 198 struct mptcp_addr_info local; 199 struct mptcp_addr_info remote; 200 struct list_head anno_list; 201 202 spinlock_t lock; /*protects the whole PM data */ 203 204 u8 addr_signal; 205 bool server_side; 206 bool work_pending; 207 bool accept_addr; 208 bool accept_subflow; 209 bool remote_deny_join_id0; 210 u8 add_addr_signaled; 211 u8 add_addr_accepted; 212 u8 local_addr_used; 213 u8 subflows; 214 u8 status; 215 DECLARE_BITMAP(id_avail_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); 216 struct mptcp_rm_list rm_list_tx; 217 struct mptcp_rm_list rm_list_rx; 218 }; 219 220 struct mptcp_data_frag { 221 struct list_head list; 222 u64 data_seq; 223 u16 data_len; 224 u16 offset; 225 u16 overhead; 226 u16 already_sent; 227 struct page *page; 228 }; 229 230 /* MPTCP connection sock */ 231 struct mptcp_sock { 232 /* inet_connection_sock must be the first member */ 233 struct inet_connection_sock sk; 234 u64 local_key; 235 u64 remote_key; 236 u64 write_seq; 237 u64 snd_nxt; 238 u64 ack_seq; 239 u64 rcv_wnd_sent; 240 u64 rcv_data_fin_seq; 241 int rmem_fwd_alloc; 242 struct sock *last_snd; 243 int snd_burst; 244 int old_wspace; 245 u64 recovery_snd_nxt; /* in recovery mode accept up to this seq; 246 * recovery related fields are under data_lock 247 * protection 248 */ 249 u64 snd_una; 250 u64 wnd_end; 251 unsigned long timer_ival; 252 u32 token; 253 int rmem_released; 254 unsigned long flags; 255 unsigned long cb_flags; 256 unsigned long push_pending; 257 bool recovery; /* closing subflow write queue reinjected */ 258 bool can_ack; 259 bool fully_established; 260 bool rcv_data_fin; 261 bool snd_data_fin_enable; 262 bool rcv_fastclose; 263 bool use_64bit_ack; /* Set when we received a 64-bit DSN */ 264 bool csum_enabled; 265 u8 recvmsg_inq:1, 266 cork:1, 267 nodelay:1; 268 struct work_struct work; 269 struct sk_buff *ooo_last_skb; 270 struct rb_root out_of_order_queue; 271 struct sk_buff_head receive_queue; 272 struct list_head conn_list; 273 struct list_head rtx_queue; 274 struct mptcp_data_frag *first_pending; 275 struct list_head join_list; 276 struct socket *subflow; /* outgoing connect/listener/!mp_capable */ 277 struct sock *first; 278 struct mptcp_pm_data pm; 279 struct { 280 u32 space; /* bytes copied in last measurement window */ 281 u32 copied; /* bytes copied in this measurement window */ 282 u64 time; /* start time of measurement window */ 283 u64 rtt_us; /* last maximum rtt of subflows */ 284 } rcvq_space; 285 286 u32 setsockopt_seq; 287 char ca_name[TCP_CA_NAME_MAX]; 288 }; 289 290 #define mptcp_data_lock(sk) spin_lock_bh(&(sk)->sk_lock.slock) 291 #define mptcp_data_unlock(sk) spin_unlock_bh(&(sk)->sk_lock.slock) 292 293 #define mptcp_for_each_subflow(__msk, __subflow) \ 294 list_for_each_entry(__subflow, &((__msk)->conn_list), node) 295 296 static inline void msk_owned_by_me(const struct mptcp_sock *msk) 297 { 298 sock_owned_by_me((const struct sock *)msk); 299 } 300 301 static inline struct mptcp_sock *mptcp_sk(const struct sock *sk) 302 { 303 return (struct mptcp_sock *)sk; 304 } 305 306 /* the msk socket don't use the backlog, also account for the bulk 307 * free memory 308 */ 309 static inline int __mptcp_rmem(const struct sock *sk) 310 { 311 return atomic_read(&sk->sk_rmem_alloc) - READ_ONCE(mptcp_sk(sk)->rmem_released); 312 } 313 314 static inline int __mptcp_space(const struct sock *sk) 315 { 316 return tcp_win_from_space(sk, READ_ONCE(sk->sk_rcvbuf) - __mptcp_rmem(sk)); 317 } 318 319 static inline struct mptcp_data_frag *mptcp_send_head(const struct sock *sk) 320 { 321 const struct mptcp_sock *msk = mptcp_sk(sk); 322 323 return READ_ONCE(msk->first_pending); 324 } 325 326 static inline struct mptcp_data_frag *mptcp_send_next(struct sock *sk) 327 { 328 struct mptcp_sock *msk = mptcp_sk(sk); 329 struct mptcp_data_frag *cur; 330 331 cur = msk->first_pending; 332 return list_is_last(&cur->list, &msk->rtx_queue) ? NULL : 333 list_next_entry(cur, list); 334 } 335 336 static inline struct mptcp_data_frag *mptcp_pending_tail(const struct sock *sk) 337 { 338 struct mptcp_sock *msk = mptcp_sk(sk); 339 340 if (!msk->first_pending) 341 return NULL; 342 343 if (WARN_ON_ONCE(list_empty(&msk->rtx_queue))) 344 return NULL; 345 346 return list_last_entry(&msk->rtx_queue, struct mptcp_data_frag, list); 347 } 348 349 static inline struct mptcp_data_frag *mptcp_rtx_head(const struct sock *sk) 350 { 351 struct mptcp_sock *msk = mptcp_sk(sk); 352 353 if (msk->snd_una == READ_ONCE(msk->snd_nxt)) 354 return NULL; 355 356 return list_first_entry_or_null(&msk->rtx_queue, struct mptcp_data_frag, list); 357 } 358 359 struct csum_pseudo_header { 360 __be64 data_seq; 361 __be32 subflow_seq; 362 __be16 data_len; 363 __sum16 csum; 364 }; 365 366 struct mptcp_subflow_request_sock { 367 struct tcp_request_sock sk; 368 u16 mp_capable : 1, 369 mp_join : 1, 370 backup : 1, 371 csum_reqd : 1, 372 allow_join_id0 : 1; 373 u8 local_id; 374 u8 remote_id; 375 u64 local_key; 376 u64 idsn; 377 u32 token; 378 u32 ssn_offset; 379 u64 thmac; 380 u32 local_nonce; 381 u32 remote_nonce; 382 struct mptcp_sock *msk; 383 struct hlist_nulls_node token_node; 384 }; 385 386 static inline struct mptcp_subflow_request_sock * 387 mptcp_subflow_rsk(const struct request_sock *rsk) 388 { 389 return (struct mptcp_subflow_request_sock *)rsk; 390 } 391 392 enum mptcp_data_avail { 393 MPTCP_SUBFLOW_NODATA, 394 MPTCP_SUBFLOW_DATA_AVAIL, 395 }; 396 397 struct mptcp_delegated_action { 398 struct napi_struct napi; 399 struct list_head head; 400 }; 401 402 DECLARE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions); 403 404 #define MPTCP_DELEGATE_SEND 0 405 #define MPTCP_DELEGATE_ACK 1 406 407 /* MPTCP subflow context */ 408 struct mptcp_subflow_context { 409 struct list_head node;/* conn_list of subflows */ 410 411 char reset_start[0]; 412 413 unsigned long avg_pacing_rate; /* protected by msk socket lock */ 414 u64 local_key; 415 u64 remote_key; 416 u64 idsn; 417 u64 map_seq; 418 u32 snd_isn; 419 u32 token; 420 u32 rel_write_seq; 421 u32 map_subflow_seq; 422 u32 ssn_offset; 423 u32 map_data_len; 424 __wsum map_data_csum; 425 u32 map_csum_len; 426 u32 request_mptcp : 1, /* send MP_CAPABLE */ 427 request_join : 1, /* send MP_JOIN */ 428 request_bkup : 1, 429 mp_capable : 1, /* remote is MPTCP capable */ 430 mp_join : 1, /* remote is JOINing */ 431 fully_established : 1, /* path validated */ 432 pm_notified : 1, /* PM hook called for established status */ 433 conn_finished : 1, 434 map_valid : 1, 435 map_csum_reqd : 1, 436 map_data_fin : 1, 437 mpc_map : 1, 438 backup : 1, 439 send_mp_prio : 1, 440 send_mp_fail : 1, 441 send_fastclose : 1, 442 rx_eof : 1, 443 can_ack : 1, /* only after processing the remote a key */ 444 disposable : 1, /* ctx can be free at ulp release time */ 445 stale : 1; /* unable to snd/rcv data, do not use for xmit */ 446 enum mptcp_data_avail data_avail; 447 u32 remote_nonce; 448 u64 thmac; 449 u32 local_nonce; 450 u32 remote_token; 451 u8 hmac[MPTCPOPT_HMAC_LEN]; 452 u8 local_id; 453 u8 remote_id; 454 u8 reset_seen:1; 455 u8 reset_transient:1; 456 u8 reset_reason:4; 457 u8 stale_count; 458 459 long delegated_status; 460 461 char reset_end[0]; 462 463 struct list_head delegated_node; /* link into delegated_action, protected by local BH */ 464 465 u32 setsockopt_seq; 466 u32 stale_rcv_tstamp; 467 468 struct sock *tcp_sock; /* tcp sk backpointer */ 469 struct sock *conn; /* parent mptcp_sock */ 470 const struct inet_connection_sock_af_ops *icsk_af_ops; 471 void (*tcp_data_ready)(struct sock *sk); 472 void (*tcp_state_change)(struct sock *sk); 473 void (*tcp_write_space)(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_start, 0, subflow->reset_end - subflow->reset_start); 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 = ctx->tcp_data_ready; 618 sk->sk_state_change = ctx->tcp_state_change; 619 sk->sk_write_space = ctx->tcp_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 sock *sk, 647 const struct sk_buff *skb, 648 struct mptcp_options_received *mp_opt); 649 650 void mptcp_finish_connect(struct sock *sk); 651 void __mptcp_set_connected(struct sock *sk); 652 static inline bool mptcp_is_fully_established(struct sock *sk) 653 { 654 return inet_sk_state_load(sk) == TCP_ESTABLISHED && 655 READ_ONCE(mptcp_sk(sk)->fully_established); 656 } 657 void mptcp_rcv_space_init(struct mptcp_sock *msk, const struct sock *ssk); 658 void mptcp_data_ready(struct sock *sk, struct sock *ssk); 659 bool mptcp_finish_join(struct sock *sk); 660 bool mptcp_schedule_work(struct sock *sk); 661 int mptcp_setsockopt(struct sock *sk, int level, int optname, 662 sockptr_t optval, unsigned int optlen); 663 int mptcp_getsockopt(struct sock *sk, int level, int optname, 664 char __user *optval, int __user *option); 665 666 u64 __mptcp_expand_seq(u64 old_seq, u64 cur_seq); 667 static inline u64 mptcp_expand_seq(u64 old_seq, u64 cur_seq, bool use_64bit) 668 { 669 if (use_64bit) 670 return cur_seq; 671 672 return __mptcp_expand_seq(old_seq, cur_seq); 673 } 674 void __mptcp_check_push(struct sock *sk, struct sock *ssk); 675 void __mptcp_data_acked(struct sock *sk); 676 void __mptcp_error_report(struct sock *sk); 677 void mptcp_subflow_eof(struct sock *sk); 678 bool mptcp_update_rcv_data_fin(struct mptcp_sock *msk, u64 data_fin_seq, bool use_64bit); 679 static inline bool mptcp_data_fin_enabled(const struct mptcp_sock *msk) 680 { 681 return READ_ONCE(msk->snd_data_fin_enable) && 682 READ_ONCE(msk->write_seq) == READ_ONCE(msk->snd_nxt); 683 } 684 685 static inline bool mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk) 686 { 687 if ((sk->sk_userlocks & SOCK_SNDBUF_LOCK) || ssk->sk_sndbuf <= READ_ONCE(sk->sk_sndbuf)) 688 return false; 689 690 WRITE_ONCE(sk->sk_sndbuf, ssk->sk_sndbuf); 691 return true; 692 } 693 694 static inline void mptcp_write_space(struct sock *sk) 695 { 696 if (sk_stream_is_writeable(sk)) { 697 /* pairs with memory barrier in mptcp_poll */ 698 smp_mb(); 699 if (test_and_clear_bit(MPTCP_NOSPACE, &mptcp_sk(sk)->flags)) 700 sk_stream_write_space(sk); 701 } 702 } 703 704 void mptcp_destroy_common(struct mptcp_sock *msk); 705 706 #define MPTCP_TOKEN_MAX_RETRIES 4 707 708 void __init mptcp_token_init(void); 709 static inline void mptcp_token_init_request(struct request_sock *req) 710 { 711 mptcp_subflow_rsk(req)->token_node.pprev = NULL; 712 } 713 714 int mptcp_token_new_request(struct request_sock *req); 715 void mptcp_token_destroy_request(struct request_sock *req); 716 int mptcp_token_new_connect(struct sock *sk); 717 void mptcp_token_accept(struct mptcp_subflow_request_sock *r, 718 struct mptcp_sock *msk); 719 bool mptcp_token_exists(u32 token); 720 struct mptcp_sock *mptcp_token_get_sock(struct net *net, u32 token); 721 struct mptcp_sock *mptcp_token_iter_next(const struct net *net, long *s_slot, 722 long *s_num); 723 void mptcp_token_destroy(struct mptcp_sock *msk); 724 725 void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn); 726 727 void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u8 *msg, int len, void *hmac); 728 u16 __mptcp_make_csum(u64 data_seq, u32 subflow_seq, u16 data_len, __wsum sum); 729 730 void __init mptcp_pm_init(void); 731 void mptcp_pm_data_init(struct mptcp_sock *msk); 732 void mptcp_pm_data_reset(struct mptcp_sock *msk); 733 void mptcp_pm_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); 734 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); 735 void mptcp_pm_new_connection(struct mptcp_sock *msk, const struct sock *ssk, int server_side); 736 void mptcp_pm_fully_established(struct mptcp_sock *msk, const struct sock *ssk, gfp_t gfp); 737 bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk); 738 void mptcp_pm_connection_closed(struct mptcp_sock *msk); 739 void mptcp_pm_subflow_established(struct mptcp_sock *msk); 740 bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk); 741 void mptcp_pm_subflow_check_next(struct mptcp_sock *msk, const struct sock *ssk, 742 const struct mptcp_subflow_context *subflow); 743 void mptcp_pm_add_addr_received(struct mptcp_sock *msk, 744 const struct mptcp_addr_info *addr); 745 void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk, 746 struct mptcp_addr_info *addr); 747 void mptcp_pm_add_addr_send_ack(struct mptcp_sock *msk); 748 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk); 749 void mptcp_pm_rm_addr_received(struct mptcp_sock *msk, 750 const struct mptcp_rm_list *rm_list); 751 void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup); 752 void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq); 753 void mptcp_pm_free_anno_list(struct mptcp_sock *msk); 754 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk); 755 struct mptcp_pm_add_entry * 756 mptcp_pm_del_add_timer(struct mptcp_sock *msk, 757 struct mptcp_addr_info *addr, bool check_id); 758 struct mptcp_pm_add_entry * 759 mptcp_lookup_anno_list_by_saddr(struct mptcp_sock *msk, 760 struct mptcp_addr_info *addr); 761 int mptcp_pm_get_flags_and_ifindex_by_id(struct net *net, unsigned int id, 762 u8 *flags, int *ifindex); 763 764 int mptcp_pm_announce_addr(struct mptcp_sock *msk, 765 const struct mptcp_addr_info *addr, 766 bool echo); 767 int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); 768 int mptcp_pm_remove_subflow(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); 769 770 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk, 771 const struct sock *ssk, gfp_t gfp); 772 void mptcp_event_addr_announced(const struct mptcp_sock *msk, const struct mptcp_addr_info *info); 773 void mptcp_event_addr_removed(const struct mptcp_sock *msk, u8 id); 774 775 static inline bool mptcp_pm_should_add_signal(struct mptcp_sock *msk) 776 { 777 return READ_ONCE(msk->pm.addr_signal) & 778 (BIT(MPTCP_ADD_ADDR_SIGNAL) | BIT(MPTCP_ADD_ADDR_ECHO)); 779 } 780 781 static inline bool mptcp_pm_should_add_signal_addr(struct mptcp_sock *msk) 782 { 783 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_SIGNAL); 784 } 785 786 static inline bool mptcp_pm_should_add_signal_echo(struct mptcp_sock *msk) 787 { 788 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_ECHO); 789 } 790 791 static inline bool mptcp_pm_should_rm_signal(struct mptcp_sock *msk) 792 { 793 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_RM_ADDR_SIGNAL); 794 } 795 796 static inline unsigned int mptcp_add_addr_len(int family, bool echo, bool port) 797 { 798 u8 len = TCPOLEN_MPTCP_ADD_ADDR_BASE; 799 800 if (family == AF_INET6) 801 len = TCPOLEN_MPTCP_ADD_ADDR6_BASE; 802 if (!echo) 803 len += MPTCPOPT_THMAC_LEN; 804 /* account for 2 trailing 'nop' options */ 805 if (port) 806 len += TCPOLEN_MPTCP_PORT_LEN + TCPOLEN_MPTCP_PORT_ALIGN; 807 808 return len; 809 } 810 811 static inline int mptcp_rm_addr_len(const struct mptcp_rm_list *rm_list) 812 { 813 if (rm_list->nr == 0 || rm_list->nr > MPTCP_RM_IDS_MAX) 814 return -EINVAL; 815 816 return TCPOLEN_MPTCP_RM_ADDR_BASE + roundup(rm_list->nr - 1, 4) + 1; 817 } 818 819 bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, struct sk_buff *skb, 820 unsigned int opt_size, unsigned int remaining, 821 struct mptcp_addr_info *addr, bool *echo, 822 bool *port, bool *drop_other_suboptions); 823 bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining, 824 struct mptcp_rm_list *rm_list); 825 int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc); 826 827 void __init mptcp_pm_nl_init(void); 828 void mptcp_pm_nl_data_init(struct mptcp_sock *msk); 829 void mptcp_pm_nl_work(struct mptcp_sock *msk); 830 void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk, 831 const struct mptcp_rm_list *rm_list); 832 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct sock_common *skc); 833 unsigned int mptcp_pm_get_add_addr_signal_max(struct mptcp_sock *msk); 834 unsigned int mptcp_pm_get_add_addr_accept_max(struct mptcp_sock *msk); 835 unsigned int mptcp_pm_get_subflows_max(struct mptcp_sock *msk); 836 unsigned int mptcp_pm_get_local_addr_max(struct mptcp_sock *msk); 837 838 void mptcp_sockopt_sync(struct mptcp_sock *msk, struct sock *ssk); 839 void mptcp_sockopt_sync_locked(struct mptcp_sock *msk, struct sock *ssk); 840 841 static inline struct mptcp_ext *mptcp_get_ext(const struct sk_buff *skb) 842 { 843 return (struct mptcp_ext *)skb_ext_find(skb, SKB_EXT_MPTCP); 844 } 845 846 void mptcp_diag_subflow_init(struct tcp_ulp_ops *ops); 847 848 static inline bool __mptcp_check_fallback(const struct mptcp_sock *msk) 849 { 850 return test_bit(MPTCP_FALLBACK_DONE, &msk->flags); 851 } 852 853 static inline bool mptcp_check_fallback(const struct sock *sk) 854 { 855 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 856 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 857 858 return __mptcp_check_fallback(msk); 859 } 860 861 static inline void __mptcp_do_fallback(struct mptcp_sock *msk) 862 { 863 if (test_bit(MPTCP_FALLBACK_DONE, &msk->flags)) { 864 pr_debug("TCP fallback already done (msk=%p)", msk); 865 return; 866 } 867 set_bit(MPTCP_FALLBACK_DONE, &msk->flags); 868 } 869 870 static inline void mptcp_do_fallback(struct sock *sk) 871 { 872 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 873 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 874 875 __mptcp_do_fallback(msk); 876 } 877 878 #define pr_fallback(a) pr_debug("%s:fallback to TCP (msk=%p)", __func__, a) 879 880 static inline bool subflow_simultaneous_connect(struct sock *sk) 881 { 882 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 883 struct sock *parent = subflow->conn; 884 885 return sk->sk_state == TCP_ESTABLISHED && 886 !mptcp_sk(parent)->pm.server_side && 887 !subflow->conn_finished; 888 } 889 890 #ifdef CONFIG_SYN_COOKIES 891 void subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 892 struct sk_buff *skb); 893 bool mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 894 struct sk_buff *skb); 895 void __init mptcp_join_cookie_init(void); 896 #else 897 static inline void 898 subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 899 struct sk_buff *skb) {} 900 static inline bool 901 mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 902 struct sk_buff *skb) 903 { 904 return false; 905 } 906 907 static inline void mptcp_join_cookie_init(void) {} 908 #endif 909 910 #endif /* __MPTCP_PROTOCOL_H */ 911