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_HMAC_LEN 20 87 #define MPTCPOPT_THMAC_LEN 8 88 89 /* MPTCP MP_CAPABLE flags */ 90 #define MPTCP_VERSION_MASK (0x0F) 91 #define MPTCP_CAP_CHECKSUM_REQD BIT(7) 92 #define MPTCP_CAP_EXTENSIBILITY BIT(6) 93 #define MPTCP_CAP_DENY_JOIN_ID0 BIT(5) 94 #define MPTCP_CAP_HMAC_SHA256 BIT(0) 95 #define MPTCP_CAP_FLAG_MASK (0x1F) 96 97 /* MPTCP DSS flags */ 98 #define MPTCP_DSS_DATA_FIN BIT(4) 99 #define MPTCP_DSS_DSN64 BIT(3) 100 #define MPTCP_DSS_HAS_MAP BIT(2) 101 #define MPTCP_DSS_ACK64 BIT(1) 102 #define MPTCP_DSS_HAS_ACK BIT(0) 103 #define MPTCP_DSS_FLAG_MASK (0x1F) 104 105 /* MPTCP ADD_ADDR flags */ 106 #define MPTCP_ADDR_ECHO BIT(0) 107 108 /* MPTCP MP_PRIO flags */ 109 #define MPTCP_PRIO_BKUP BIT(0) 110 111 /* MPTCP TCPRST flags */ 112 #define MPTCP_RST_TRANSIENT BIT(0) 113 114 /* MPTCP socket atomic flags */ 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_FAIL_NO_RESPONSE 6 121 122 /* MPTCP socket release cb flags */ 123 #define MPTCP_PUSH_PENDING 1 124 #define MPTCP_CLEAN_UNA 2 125 #define MPTCP_ERROR_REPORT 3 126 #define MPTCP_RETRANSMIT 4 127 #define MPTCP_FLUSH_JOIN_LIST 5 128 #define MPTCP_CONNECTED 6 129 #define MPTCP_RESET_SCHEDULER 7 130 131 static inline bool before64(__u64 seq1, __u64 seq2) 132 { 133 return (__s64)(seq1 - seq2) < 0; 134 } 135 136 #define after64(seq2, seq1) before64(seq1, seq2) 137 138 struct mptcp_options_received { 139 u64 sndr_key; 140 u64 rcvr_key; 141 u64 data_ack; 142 u64 data_seq; 143 u32 subflow_seq; 144 u16 data_len; 145 __sum16 csum; 146 u16 suboptions; 147 u32 token; 148 u32 nonce; 149 u16 use_map:1, 150 dsn64:1, 151 data_fin:1, 152 use_ack:1, 153 ack64:1, 154 mpc_map:1, 155 reset_reason:4, 156 reset_transient:1, 157 echo:1, 158 backup:1, 159 deny_join_id0:1, 160 __unused:2; 161 u8 join_id; 162 u64 thmac; 163 u8 hmac[MPTCPOPT_HMAC_LEN]; 164 struct mptcp_addr_info addr; 165 struct mptcp_rm_list rm_list; 166 u64 ahmac; 167 u64 fail_seq; 168 }; 169 170 static inline __be32 mptcp_option(u8 subopt, u8 len, u8 nib, u8 field) 171 { 172 return htonl((TCPOPT_MPTCP << 24) | (len << 16) | (subopt << 12) | 173 ((nib & 0xF) << 8) | field); 174 } 175 176 enum mptcp_pm_status { 177 MPTCP_PM_ADD_ADDR_RECEIVED, 178 MPTCP_PM_ADD_ADDR_SEND_ACK, 179 MPTCP_PM_RM_ADDR_RECEIVED, 180 MPTCP_PM_ESTABLISHED, 181 MPTCP_PM_SUBFLOW_ESTABLISHED, 182 MPTCP_PM_ALREADY_ESTABLISHED, /* persistent status, set after ESTABLISHED event */ 183 MPTCP_PM_MPC_ENDPOINT_ACCOUNTED /* persistent status, set after MPC local address is 184 * accounted int id_avail_bitmap 185 */ 186 }; 187 188 enum mptcp_pm_type { 189 MPTCP_PM_TYPE_KERNEL = 0, 190 MPTCP_PM_TYPE_USERSPACE, 191 192 __MPTCP_PM_TYPE_NR, 193 __MPTCP_PM_TYPE_MAX = __MPTCP_PM_TYPE_NR - 1, 194 }; 195 196 /* Status bits below MPTCP_PM_ALREADY_ESTABLISHED need pm worker actions */ 197 #define MPTCP_PM_WORK_MASK ((1 << MPTCP_PM_ALREADY_ESTABLISHED) - 1) 198 199 enum mptcp_addr_signal_status { 200 MPTCP_ADD_ADDR_SIGNAL, 201 MPTCP_ADD_ADDR_ECHO, 202 MPTCP_RM_ADDR_SIGNAL, 203 }; 204 205 /* max value of mptcp_addr_info.id */ 206 #define MPTCP_PM_MAX_ADDR_ID U8_MAX 207 208 struct mptcp_pm_data { 209 struct mptcp_addr_info local; 210 struct mptcp_addr_info remote; 211 struct list_head anno_list; 212 struct list_head userspace_pm_local_addr_list; 213 214 spinlock_t lock; /*protects the whole PM data */ 215 216 u8 addr_signal; 217 bool server_side; 218 bool work_pending; 219 bool accept_addr; 220 bool accept_subflow; 221 bool remote_deny_join_id0; 222 u8 add_addr_signaled; 223 u8 add_addr_accepted; 224 u8 local_addr_used; 225 u8 pm_type; 226 u8 subflows; 227 u8 status; 228 DECLARE_BITMAP(id_avail_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); 229 struct mptcp_rm_list rm_list_tx; 230 struct mptcp_rm_list rm_list_rx; 231 }; 232 233 struct mptcp_pm_addr_entry { 234 struct list_head list; 235 struct mptcp_addr_info addr; 236 u8 flags; 237 int ifindex; 238 struct socket *lsk; 239 }; 240 241 struct mptcp_data_frag { 242 struct list_head list; 243 u64 data_seq; 244 u16 data_len; 245 u16 offset; 246 u16 overhead; 247 u16 already_sent; 248 struct page *page; 249 }; 250 251 /* MPTCP connection sock */ 252 struct mptcp_sock { 253 /* inet_connection_sock must be the first member */ 254 struct inet_connection_sock sk; 255 u64 local_key; 256 u64 remote_key; 257 u64 write_seq; 258 u64 snd_nxt; 259 u64 ack_seq; 260 atomic64_t rcv_wnd_sent; 261 u64 rcv_data_fin_seq; 262 int rmem_fwd_alloc; 263 struct sock *last_snd; 264 int snd_burst; 265 int old_wspace; 266 u64 recovery_snd_nxt; /* in recovery mode accept up to this seq; 267 * recovery related fields are under data_lock 268 * protection 269 */ 270 u64 snd_una; 271 u64 wnd_end; 272 unsigned long timer_ival; 273 u32 token; 274 int rmem_released; 275 unsigned long flags; 276 unsigned long cb_flags; 277 unsigned long push_pending; 278 bool recovery; /* closing subflow write queue reinjected */ 279 bool can_ack; 280 bool fully_established; 281 bool rcv_data_fin; 282 bool snd_data_fin_enable; 283 bool rcv_fastclose; 284 bool use_64bit_ack; /* Set when we received a 64-bit DSN */ 285 bool csum_enabled; 286 bool allow_infinite_fallback; 287 u8 recvmsg_inq:1, 288 cork:1, 289 nodelay:1; 290 struct work_struct work; 291 struct sk_buff *ooo_last_skb; 292 struct rb_root out_of_order_queue; 293 struct sk_buff_head receive_queue; 294 struct list_head conn_list; 295 struct list_head rtx_queue; 296 struct mptcp_data_frag *first_pending; 297 struct list_head join_list; 298 struct socket *subflow; /* outgoing connect/listener/!mp_capable */ 299 struct sock *first; 300 struct mptcp_pm_data pm; 301 struct { 302 u32 space; /* bytes copied in last measurement window */ 303 u32 copied; /* bytes copied in this measurement window */ 304 u64 time; /* start time of measurement window */ 305 u64 rtt_us; /* last maximum rtt of subflows */ 306 } rcvq_space; 307 308 u32 setsockopt_seq; 309 char ca_name[TCP_CA_NAME_MAX]; 310 }; 311 312 #define mptcp_data_lock(sk) spin_lock_bh(&(sk)->sk_lock.slock) 313 #define mptcp_data_unlock(sk) spin_unlock_bh(&(sk)->sk_lock.slock) 314 315 #define mptcp_for_each_subflow(__msk, __subflow) \ 316 list_for_each_entry(__subflow, &((__msk)->conn_list), node) 317 318 static inline void msk_owned_by_me(const struct mptcp_sock *msk) 319 { 320 sock_owned_by_me((const struct sock *)msk); 321 } 322 323 static inline struct mptcp_sock *mptcp_sk(const struct sock *sk) 324 { 325 return (struct mptcp_sock *)sk; 326 } 327 328 /* the msk socket don't use the backlog, also account for the bulk 329 * free memory 330 */ 331 static inline int __mptcp_rmem(const struct sock *sk) 332 { 333 return atomic_read(&sk->sk_rmem_alloc) - READ_ONCE(mptcp_sk(sk)->rmem_released); 334 } 335 336 static inline int __mptcp_space(const struct sock *sk) 337 { 338 return tcp_win_from_space(sk, READ_ONCE(sk->sk_rcvbuf) - __mptcp_rmem(sk)); 339 } 340 341 static inline struct mptcp_data_frag *mptcp_send_head(const struct sock *sk) 342 { 343 const struct mptcp_sock *msk = mptcp_sk(sk); 344 345 return READ_ONCE(msk->first_pending); 346 } 347 348 static inline struct mptcp_data_frag *mptcp_send_next(struct sock *sk) 349 { 350 struct mptcp_sock *msk = mptcp_sk(sk); 351 struct mptcp_data_frag *cur; 352 353 cur = msk->first_pending; 354 return list_is_last(&cur->list, &msk->rtx_queue) ? NULL : 355 list_next_entry(cur, list); 356 } 357 358 static inline struct mptcp_data_frag *mptcp_pending_tail(const struct sock *sk) 359 { 360 struct mptcp_sock *msk = mptcp_sk(sk); 361 362 if (!msk->first_pending) 363 return NULL; 364 365 if (WARN_ON_ONCE(list_empty(&msk->rtx_queue))) 366 return NULL; 367 368 return list_last_entry(&msk->rtx_queue, struct mptcp_data_frag, list); 369 } 370 371 static inline struct mptcp_data_frag *mptcp_rtx_head(const struct sock *sk) 372 { 373 struct mptcp_sock *msk = mptcp_sk(sk); 374 375 if (msk->snd_una == READ_ONCE(msk->snd_nxt)) 376 return NULL; 377 378 return list_first_entry_or_null(&msk->rtx_queue, struct mptcp_data_frag, list); 379 } 380 381 struct csum_pseudo_header { 382 __be64 data_seq; 383 __be32 subflow_seq; 384 __be16 data_len; 385 __sum16 csum; 386 }; 387 388 struct mptcp_subflow_request_sock { 389 struct tcp_request_sock sk; 390 u16 mp_capable : 1, 391 mp_join : 1, 392 backup : 1, 393 csum_reqd : 1, 394 allow_join_id0 : 1; 395 u8 local_id; 396 u8 remote_id; 397 u64 local_key; 398 u64 idsn; 399 u32 token; 400 u32 ssn_offset; 401 u64 thmac; 402 u32 local_nonce; 403 u32 remote_nonce; 404 struct mptcp_sock *msk; 405 struct hlist_nulls_node token_node; 406 }; 407 408 static inline struct mptcp_subflow_request_sock * 409 mptcp_subflow_rsk(const struct request_sock *rsk) 410 { 411 return (struct mptcp_subflow_request_sock *)rsk; 412 } 413 414 enum mptcp_data_avail { 415 MPTCP_SUBFLOW_NODATA, 416 MPTCP_SUBFLOW_DATA_AVAIL, 417 }; 418 419 struct mptcp_delegated_action { 420 struct napi_struct napi; 421 struct list_head head; 422 }; 423 424 DECLARE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions); 425 426 #define MPTCP_DELEGATE_SEND 0 427 #define MPTCP_DELEGATE_ACK 1 428 429 /* MPTCP subflow context */ 430 struct mptcp_subflow_context { 431 struct list_head node;/* conn_list of subflows */ 432 433 struct_group(reset, 434 435 unsigned long avg_pacing_rate; /* protected by msk socket lock */ 436 u64 local_key; 437 u64 remote_key; 438 u64 idsn; 439 u64 map_seq; 440 u32 snd_isn; 441 u32 token; 442 u32 rel_write_seq; 443 u32 map_subflow_seq; 444 u32 ssn_offset; 445 u32 map_data_len; 446 __wsum map_data_csum; 447 u32 map_csum_len; 448 u32 request_mptcp : 1, /* send MP_CAPABLE */ 449 request_join : 1, /* send MP_JOIN */ 450 request_bkup : 1, 451 mp_capable : 1, /* remote is MPTCP capable */ 452 mp_join : 1, /* remote is JOINing */ 453 fully_established : 1, /* path validated */ 454 pm_notified : 1, /* PM hook called for established status */ 455 conn_finished : 1, 456 map_valid : 1, 457 map_csum_reqd : 1, 458 map_data_fin : 1, 459 mpc_map : 1, 460 backup : 1, 461 send_mp_prio : 1, 462 send_mp_fail : 1, 463 send_fastclose : 1, 464 send_infinite_map : 1, 465 rx_eof : 1, 466 can_ack : 1, /* only after processing the remote a key */ 467 disposable : 1, /* ctx can be free at ulp release time */ 468 stale : 1, /* unable to snd/rcv data, do not use for xmit */ 469 local_id_valid : 1, /* local_id is correctly initialized */ 470 valid_csum_seen : 1; /* at least one csum validated */ 471 enum mptcp_data_avail data_avail; 472 bool mp_fail_response_expect; 473 u32 remote_nonce; 474 u64 thmac; 475 u32 local_nonce; 476 u32 remote_token; 477 u8 hmac[MPTCPOPT_HMAC_LEN]; 478 u8 local_id; 479 u8 remote_id; 480 u8 reset_seen:1; 481 u8 reset_transient:1; 482 u8 reset_reason:4; 483 u8 stale_count; 484 485 long delegated_status; 486 487 ); 488 489 struct list_head delegated_node; /* link into delegated_action, protected by local BH */ 490 491 u32 setsockopt_seq; 492 u32 stale_rcv_tstamp; 493 494 struct sock *tcp_sock; /* tcp sk backpointer */ 495 struct sock *conn; /* parent mptcp_sock */ 496 const struct inet_connection_sock_af_ops *icsk_af_ops; 497 void (*tcp_state_change)(struct sock *sk); 498 void (*tcp_error_report)(struct sock *sk); 499 500 struct rcu_head rcu; 501 }; 502 503 static inline struct mptcp_subflow_context * 504 mptcp_subflow_ctx(const struct sock *sk) 505 { 506 struct inet_connection_sock *icsk = inet_csk(sk); 507 508 /* Use RCU on icsk_ulp_data only for sock diag code */ 509 return (__force struct mptcp_subflow_context *)icsk->icsk_ulp_data; 510 } 511 512 static inline struct sock * 513 mptcp_subflow_tcp_sock(const struct mptcp_subflow_context *subflow) 514 { 515 return subflow->tcp_sock; 516 } 517 518 static inline void 519 mptcp_subflow_ctx_reset(struct mptcp_subflow_context *subflow) 520 { 521 memset(&subflow->reset, 0, sizeof(subflow->reset)); 522 subflow->request_mptcp = 1; 523 } 524 525 static inline u64 526 mptcp_subflow_get_map_offset(const struct mptcp_subflow_context *subflow) 527 { 528 return tcp_sk(mptcp_subflow_tcp_sock(subflow))->copied_seq - 529 subflow->ssn_offset - 530 subflow->map_subflow_seq; 531 } 532 533 static inline u64 534 mptcp_subflow_get_mapped_dsn(const struct mptcp_subflow_context *subflow) 535 { 536 return subflow->map_seq + mptcp_subflow_get_map_offset(subflow); 537 } 538 539 void mptcp_subflow_process_delegated(struct sock *ssk); 540 541 static inline void mptcp_subflow_delegate(struct mptcp_subflow_context *subflow, int action) 542 { 543 struct mptcp_delegated_action *delegated; 544 bool schedule; 545 546 /* the caller held the subflow bh socket lock */ 547 lockdep_assert_in_softirq(); 548 549 /* The implied barrier pairs with mptcp_subflow_delegated_done(), and 550 * ensures the below list check sees list updates done prior to status 551 * bit changes 552 */ 553 if (!test_and_set_bit(action, &subflow->delegated_status)) { 554 /* still on delegated list from previous scheduling */ 555 if (!list_empty(&subflow->delegated_node)) 556 return; 557 558 delegated = this_cpu_ptr(&mptcp_delegated_actions); 559 schedule = list_empty(&delegated->head); 560 list_add_tail(&subflow->delegated_node, &delegated->head); 561 sock_hold(mptcp_subflow_tcp_sock(subflow)); 562 if (schedule) 563 napi_schedule(&delegated->napi); 564 } 565 } 566 567 static inline struct mptcp_subflow_context * 568 mptcp_subflow_delegated_next(struct mptcp_delegated_action *delegated) 569 { 570 struct mptcp_subflow_context *ret; 571 572 if (list_empty(&delegated->head)) 573 return NULL; 574 575 ret = list_first_entry(&delegated->head, struct mptcp_subflow_context, delegated_node); 576 list_del_init(&ret->delegated_node); 577 return ret; 578 } 579 580 static inline bool mptcp_subflow_has_delegated_action(const struct mptcp_subflow_context *subflow) 581 { 582 return !!READ_ONCE(subflow->delegated_status); 583 } 584 585 static inline void mptcp_subflow_delegated_done(struct mptcp_subflow_context *subflow, int action) 586 { 587 /* pairs with mptcp_subflow_delegate, ensures delegate_node is updated before 588 * touching the status bit 589 */ 590 smp_wmb(); 591 clear_bit(action, &subflow->delegated_status); 592 } 593 594 int mptcp_is_enabled(const struct net *net); 595 unsigned int mptcp_get_add_addr_timeout(const struct net *net); 596 int mptcp_is_checksum_enabled(const struct net *net); 597 int mptcp_allow_join_id0(const struct net *net); 598 unsigned int mptcp_stale_loss_cnt(const struct net *net); 599 int mptcp_get_pm_type(const struct net *net); 600 void mptcp_subflow_fully_established(struct mptcp_subflow_context *subflow, 601 struct mptcp_options_received *mp_opt); 602 bool __mptcp_retransmit_pending_data(struct sock *sk); 603 void mptcp_check_and_set_pending(struct sock *sk); 604 void __mptcp_push_pending(struct sock *sk, unsigned int flags); 605 bool mptcp_subflow_data_available(struct sock *sk); 606 void __init mptcp_subflow_init(void); 607 void mptcp_subflow_shutdown(struct sock *sk, struct sock *ssk, int how); 608 void mptcp_close_ssk(struct sock *sk, struct sock *ssk, 609 struct mptcp_subflow_context *subflow); 610 void mptcp_subflow_send_ack(struct sock *ssk); 611 void mptcp_subflow_reset(struct sock *ssk); 612 void mptcp_sock_graft(struct sock *sk, struct socket *parent); 613 struct socket *__mptcp_nmpc_socket(const struct mptcp_sock *msk); 614 615 bool mptcp_addresses_equal(const struct mptcp_addr_info *a, 616 const struct mptcp_addr_info *b, bool use_port); 617 618 /* called with sk socket lock held */ 619 int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_addr_info *loc, 620 const struct mptcp_addr_info *remote); 621 int mptcp_subflow_create_socket(struct sock *sk, struct socket **new_sock); 622 void mptcp_info2sockaddr(const struct mptcp_addr_info *info, 623 struct sockaddr_storage *addr, 624 unsigned short family); 625 626 static inline bool __mptcp_subflow_active(struct mptcp_subflow_context *subflow) 627 { 628 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 629 630 /* can't send if JOIN hasn't completed yet (i.e. is usable for mptcp) */ 631 if (subflow->request_join && !subflow->fully_established) 632 return false; 633 634 /* only send if our side has not closed yet */ 635 return ((1 << ssk->sk_state) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)); 636 } 637 638 void mptcp_subflow_set_active(struct mptcp_subflow_context *subflow); 639 640 bool mptcp_subflow_active(struct mptcp_subflow_context *subflow); 641 642 static inline void mptcp_subflow_tcp_fallback(struct sock *sk, 643 struct mptcp_subflow_context *ctx) 644 { 645 sk->sk_data_ready = sock_def_readable; 646 sk->sk_state_change = ctx->tcp_state_change; 647 sk->sk_write_space = sk_stream_write_space; 648 sk->sk_error_report = ctx->tcp_error_report; 649 650 inet_csk(sk)->icsk_af_ops = ctx->icsk_af_ops; 651 } 652 653 static inline bool mptcp_has_another_subflow(struct sock *ssk) 654 { 655 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk), *tmp; 656 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 657 658 mptcp_for_each_subflow(msk, tmp) { 659 if (tmp != subflow) 660 return true; 661 } 662 663 return false; 664 } 665 666 void __init mptcp_proto_init(void); 667 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 668 int __init mptcp_proto_v6_init(void); 669 #endif 670 671 struct sock *mptcp_sk_clone(const struct sock *sk, 672 const struct mptcp_options_received *mp_opt, 673 struct request_sock *req); 674 void mptcp_get_options(const struct sk_buff *skb, 675 struct mptcp_options_received *mp_opt); 676 677 void mptcp_finish_connect(struct sock *sk); 678 void __mptcp_set_connected(struct sock *sk); 679 static inline bool mptcp_is_fully_established(struct sock *sk) 680 { 681 return inet_sk_state_load(sk) == TCP_ESTABLISHED && 682 READ_ONCE(mptcp_sk(sk)->fully_established); 683 } 684 void mptcp_rcv_space_init(struct mptcp_sock *msk, const struct sock *ssk); 685 void mptcp_data_ready(struct sock *sk, struct sock *ssk); 686 bool mptcp_finish_join(struct sock *sk); 687 bool mptcp_schedule_work(struct sock *sk); 688 int mptcp_setsockopt(struct sock *sk, int level, int optname, 689 sockptr_t optval, unsigned int optlen); 690 int mptcp_getsockopt(struct sock *sk, int level, int optname, 691 char __user *optval, int __user *option); 692 693 u64 __mptcp_expand_seq(u64 old_seq, u64 cur_seq); 694 static inline u64 mptcp_expand_seq(u64 old_seq, u64 cur_seq, bool use_64bit) 695 { 696 if (use_64bit) 697 return cur_seq; 698 699 return __mptcp_expand_seq(old_seq, cur_seq); 700 } 701 void __mptcp_check_push(struct sock *sk, struct sock *ssk); 702 void __mptcp_data_acked(struct sock *sk); 703 void __mptcp_error_report(struct sock *sk); 704 void mptcp_subflow_eof(struct sock *sk); 705 bool mptcp_update_rcv_data_fin(struct mptcp_sock *msk, u64 data_fin_seq, bool use_64bit); 706 static inline bool mptcp_data_fin_enabled(const struct mptcp_sock *msk) 707 { 708 return READ_ONCE(msk->snd_data_fin_enable) && 709 READ_ONCE(msk->write_seq) == READ_ONCE(msk->snd_nxt); 710 } 711 712 static inline bool mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk) 713 { 714 if ((sk->sk_userlocks & SOCK_SNDBUF_LOCK) || ssk->sk_sndbuf <= READ_ONCE(sk->sk_sndbuf)) 715 return false; 716 717 WRITE_ONCE(sk->sk_sndbuf, ssk->sk_sndbuf); 718 return true; 719 } 720 721 static inline void mptcp_write_space(struct sock *sk) 722 { 723 if (sk_stream_is_writeable(sk)) { 724 /* pairs with memory barrier in mptcp_poll */ 725 smp_mb(); 726 if (test_and_clear_bit(MPTCP_NOSPACE, &mptcp_sk(sk)->flags)) 727 sk_stream_write_space(sk); 728 } 729 } 730 731 void mptcp_destroy_common(struct mptcp_sock *msk); 732 733 #define MPTCP_TOKEN_MAX_RETRIES 4 734 735 void __init mptcp_token_init(void); 736 static inline void mptcp_token_init_request(struct request_sock *req) 737 { 738 mptcp_subflow_rsk(req)->token_node.pprev = NULL; 739 } 740 741 int mptcp_token_new_request(struct request_sock *req); 742 void mptcp_token_destroy_request(struct request_sock *req); 743 int mptcp_token_new_connect(struct sock *sk); 744 void mptcp_token_accept(struct mptcp_subflow_request_sock *r, 745 struct mptcp_sock *msk); 746 bool mptcp_token_exists(u32 token); 747 struct mptcp_sock *mptcp_token_get_sock(struct net *net, u32 token); 748 struct mptcp_sock *mptcp_token_iter_next(const struct net *net, long *s_slot, 749 long *s_num); 750 void mptcp_token_destroy(struct mptcp_sock *msk); 751 752 void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn); 753 754 void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u8 *msg, int len, void *hmac); 755 __sum16 __mptcp_make_csum(u64 data_seq, u32 subflow_seq, u16 data_len, __wsum sum); 756 757 void __init mptcp_pm_init(void); 758 void mptcp_pm_data_init(struct mptcp_sock *msk); 759 void mptcp_pm_data_reset(struct mptcp_sock *msk); 760 int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info, 761 struct mptcp_addr_info *addr); 762 int mptcp_pm_parse_entry(struct nlattr *attr, struct genl_info *info, 763 bool require_family, 764 struct mptcp_pm_addr_entry *entry); 765 void mptcp_pm_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); 766 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); 767 void mptcp_pm_new_connection(struct mptcp_sock *msk, const struct sock *ssk, int server_side); 768 void mptcp_pm_fully_established(struct mptcp_sock *msk, const struct sock *ssk, gfp_t gfp); 769 bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk); 770 void mptcp_pm_connection_closed(struct mptcp_sock *msk); 771 void mptcp_pm_subflow_established(struct mptcp_sock *msk); 772 bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk); 773 void mptcp_pm_subflow_check_next(struct mptcp_sock *msk, const struct sock *ssk, 774 const struct mptcp_subflow_context *subflow); 775 void mptcp_pm_add_addr_received(const struct sock *ssk, 776 const struct mptcp_addr_info *addr); 777 void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk, 778 const struct mptcp_addr_info *addr); 779 void mptcp_pm_add_addr_send_ack(struct mptcp_sock *msk); 780 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk); 781 void mptcp_pm_rm_addr_received(struct mptcp_sock *msk, 782 const struct mptcp_rm_list *rm_list); 783 void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup); 784 void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq); 785 bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk, 786 const struct mptcp_pm_addr_entry *entry); 787 void mptcp_pm_free_anno_list(struct mptcp_sock *msk); 788 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk); 789 struct mptcp_pm_add_entry * 790 mptcp_pm_del_add_timer(struct mptcp_sock *msk, 791 const struct mptcp_addr_info *addr, bool check_id); 792 struct mptcp_pm_add_entry * 793 mptcp_lookup_anno_list_by_saddr(const struct mptcp_sock *msk, 794 const struct mptcp_addr_info *addr); 795 int mptcp_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, 796 unsigned int id, 797 u8 *flags, int *ifindex); 798 int mptcp_userspace_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, 799 unsigned int id, 800 u8 *flags, int *ifindex); 801 802 int mptcp_pm_announce_addr(struct mptcp_sock *msk, 803 const struct mptcp_addr_info *addr, 804 bool echo); 805 int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); 806 int mptcp_pm_remove_subflow(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); 807 void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk, 808 struct list_head *rm_list); 809 810 int mptcp_userspace_pm_append_new_local_addr(struct mptcp_sock *msk, 811 struct mptcp_pm_addr_entry *entry); 812 void mptcp_free_local_addr_list(struct mptcp_sock *msk); 813 int mptcp_nl_cmd_announce(struct sk_buff *skb, struct genl_info *info); 814 int mptcp_nl_cmd_remove(struct sk_buff *skb, struct genl_info *info); 815 int mptcp_nl_cmd_sf_create(struct sk_buff *skb, struct genl_info *info); 816 int mptcp_nl_cmd_sf_destroy(struct sk_buff *skb, struct genl_info *info); 817 818 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk, 819 const struct sock *ssk, gfp_t gfp); 820 void mptcp_event_addr_announced(const struct sock *ssk, const struct mptcp_addr_info *info); 821 void mptcp_event_addr_removed(const struct mptcp_sock *msk, u8 id); 822 bool mptcp_userspace_pm_active(const struct mptcp_sock *msk); 823 824 static inline bool mptcp_pm_should_add_signal(struct mptcp_sock *msk) 825 { 826 return READ_ONCE(msk->pm.addr_signal) & 827 (BIT(MPTCP_ADD_ADDR_SIGNAL) | BIT(MPTCP_ADD_ADDR_ECHO)); 828 } 829 830 static inline bool mptcp_pm_should_add_signal_addr(struct mptcp_sock *msk) 831 { 832 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_SIGNAL); 833 } 834 835 static inline bool mptcp_pm_should_add_signal_echo(struct mptcp_sock *msk) 836 { 837 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_ECHO); 838 } 839 840 static inline bool mptcp_pm_should_rm_signal(struct mptcp_sock *msk) 841 { 842 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_RM_ADDR_SIGNAL); 843 } 844 845 static inline bool mptcp_pm_is_userspace(const struct mptcp_sock *msk) 846 { 847 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_USERSPACE; 848 } 849 850 static inline bool mptcp_pm_is_kernel(const struct mptcp_sock *msk) 851 { 852 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_KERNEL; 853 } 854 855 static inline unsigned int mptcp_add_addr_len(int family, bool echo, bool port) 856 { 857 u8 len = TCPOLEN_MPTCP_ADD_ADDR_BASE; 858 859 if (family == AF_INET6) 860 len = TCPOLEN_MPTCP_ADD_ADDR6_BASE; 861 if (!echo) 862 len += MPTCPOPT_THMAC_LEN; 863 /* account for 2 trailing 'nop' options */ 864 if (port) 865 len += TCPOLEN_MPTCP_PORT_LEN + TCPOLEN_MPTCP_PORT_ALIGN; 866 867 return len; 868 } 869 870 static inline int mptcp_rm_addr_len(const struct mptcp_rm_list *rm_list) 871 { 872 if (rm_list->nr == 0 || rm_list->nr > MPTCP_RM_IDS_MAX) 873 return -EINVAL; 874 875 return TCPOLEN_MPTCP_RM_ADDR_BASE + roundup(rm_list->nr - 1, 4) + 1; 876 } 877 878 bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, const struct sk_buff *skb, 879 unsigned int opt_size, unsigned int remaining, 880 struct mptcp_addr_info *addr, bool *echo, 881 bool *drop_other_suboptions); 882 bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining, 883 struct mptcp_rm_list *rm_list); 884 int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc); 885 int mptcp_userspace_pm_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc); 886 887 void __init mptcp_pm_nl_init(void); 888 void mptcp_pm_nl_work(struct mptcp_sock *msk); 889 void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk, 890 const struct mptcp_rm_list *rm_list); 891 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct sock_common *skc); 892 unsigned int mptcp_pm_get_add_addr_signal_max(const struct mptcp_sock *msk); 893 unsigned int mptcp_pm_get_add_addr_accept_max(const struct mptcp_sock *msk); 894 unsigned int mptcp_pm_get_subflows_max(const struct mptcp_sock *msk); 895 unsigned int mptcp_pm_get_local_addr_max(const struct mptcp_sock *msk); 896 897 /* called under PM lock */ 898 static inline void __mptcp_pm_close_subflow(struct mptcp_sock *msk) 899 { 900 if (--msk->pm.subflows < mptcp_pm_get_subflows_max(msk)) 901 WRITE_ONCE(msk->pm.accept_subflow, true); 902 } 903 904 static inline void mptcp_pm_close_subflow(struct mptcp_sock *msk) 905 { 906 spin_lock_bh(&msk->pm.lock); 907 __mptcp_pm_close_subflow(msk); 908 spin_unlock_bh(&msk->pm.lock); 909 } 910 911 void mptcp_sockopt_sync(struct mptcp_sock *msk, struct sock *ssk); 912 void mptcp_sockopt_sync_locked(struct mptcp_sock *msk, struct sock *ssk); 913 914 static inline struct mptcp_ext *mptcp_get_ext(const struct sk_buff *skb) 915 { 916 return (struct mptcp_ext *)skb_ext_find(skb, SKB_EXT_MPTCP); 917 } 918 919 void mptcp_diag_subflow_init(struct tcp_ulp_ops *ops); 920 921 static inline bool __mptcp_check_fallback(const struct mptcp_sock *msk) 922 { 923 return test_bit(MPTCP_FALLBACK_DONE, &msk->flags); 924 } 925 926 static inline bool mptcp_check_fallback(const struct sock *sk) 927 { 928 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 929 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 930 931 return __mptcp_check_fallback(msk); 932 } 933 934 static inline void __mptcp_do_fallback(struct mptcp_sock *msk) 935 { 936 if (test_bit(MPTCP_FALLBACK_DONE, &msk->flags)) { 937 pr_debug("TCP fallback already done (msk=%p)", msk); 938 return; 939 } 940 set_bit(MPTCP_FALLBACK_DONE, &msk->flags); 941 } 942 943 static inline void mptcp_do_fallback(struct sock *sk) 944 { 945 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 946 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 947 948 __mptcp_do_fallback(msk); 949 } 950 951 #define pr_fallback(a) pr_debug("%s:fallback to TCP (msk=%p)", __func__, a) 952 953 static inline bool mptcp_check_infinite_map(struct sk_buff *skb) 954 { 955 struct mptcp_ext *mpext; 956 957 mpext = skb ? mptcp_get_ext(skb) : NULL; 958 if (mpext && mpext->infinite_map) 959 return true; 960 961 return false; 962 } 963 964 static inline bool is_active_ssk(struct mptcp_subflow_context *subflow) 965 { 966 return (subflow->request_mptcp || subflow->request_join); 967 } 968 969 static inline bool subflow_simultaneous_connect(struct sock *sk) 970 { 971 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 972 973 return sk->sk_state == TCP_ESTABLISHED && 974 is_active_ssk(subflow) && 975 !subflow->conn_finished; 976 } 977 978 #ifdef CONFIG_SYN_COOKIES 979 void subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 980 struct sk_buff *skb); 981 bool mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 982 struct sk_buff *skb); 983 void __init mptcp_join_cookie_init(void); 984 #else 985 static inline void 986 subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 987 struct sk_buff *skb) {} 988 static inline bool 989 mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 990 struct sk_buff *skb) 991 { 992 return false; 993 } 994 995 static inline void mptcp_join_cookie_init(void) {} 996 #endif 997 998 #endif /* __MPTCP_PROTOCOL_H */ 999