1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* Multipath TCP 3 * 4 * Copyright (c) 2017 - 2019, Intel Corporation. 5 */ 6 7 #ifndef __MPTCP_PROTOCOL_H 8 #define __MPTCP_PROTOCOL_H 9 10 #include <linux/random.h> 11 #include <net/tcp.h> 12 #include <net/inet_connection_sock.h> 13 #include <uapi/linux/mptcp.h> 14 #include <net/genetlink.h> 15 16 #define MPTCP_SUPPORTED_VERSION 1 17 18 /* MPTCP option bits */ 19 #define OPTION_MPTCP_MPC_SYN BIT(0) 20 #define OPTION_MPTCP_MPC_SYNACK BIT(1) 21 #define OPTION_MPTCP_MPC_ACK BIT(2) 22 #define OPTION_MPTCP_MPJ_SYN BIT(3) 23 #define OPTION_MPTCP_MPJ_SYNACK BIT(4) 24 #define OPTION_MPTCP_MPJ_ACK BIT(5) 25 #define OPTION_MPTCP_ADD_ADDR BIT(6) 26 #define OPTION_MPTCP_RM_ADDR BIT(7) 27 #define OPTION_MPTCP_FASTCLOSE BIT(8) 28 #define OPTION_MPTCP_PRIO BIT(9) 29 #define OPTION_MPTCP_RST BIT(10) 30 #define OPTION_MPTCP_DSS BIT(11) 31 #define OPTION_MPTCP_FAIL BIT(12) 32 33 #define OPTION_MPTCP_CSUMREQD BIT(13) 34 35 #define OPTIONS_MPTCP_MPC (OPTION_MPTCP_MPC_SYN | OPTION_MPTCP_MPC_SYNACK | \ 36 OPTION_MPTCP_MPC_ACK) 37 #define OPTIONS_MPTCP_MPJ (OPTION_MPTCP_MPJ_SYN | OPTION_MPTCP_MPJ_SYNACK | \ 38 OPTION_MPTCP_MPJ_ACK) 39 40 /* MPTCP option subtypes */ 41 #define MPTCPOPT_MP_CAPABLE 0 42 #define MPTCPOPT_MP_JOIN 1 43 #define MPTCPOPT_DSS 2 44 #define MPTCPOPT_ADD_ADDR 3 45 #define MPTCPOPT_RM_ADDR 4 46 #define MPTCPOPT_MP_PRIO 5 47 #define MPTCPOPT_MP_FAIL 6 48 #define MPTCPOPT_MP_FASTCLOSE 7 49 #define MPTCPOPT_RST 8 50 51 /* MPTCP suboption lengths */ 52 #define TCPOLEN_MPTCP_MPC_SYN 4 53 #define TCPOLEN_MPTCP_MPC_SYNACK 12 54 #define TCPOLEN_MPTCP_MPC_ACK 20 55 #define TCPOLEN_MPTCP_MPC_ACK_DATA 22 56 #define TCPOLEN_MPTCP_MPJ_SYN 12 57 #define TCPOLEN_MPTCP_MPJ_SYNACK 16 58 #define TCPOLEN_MPTCP_MPJ_ACK 24 59 #define TCPOLEN_MPTCP_DSS_BASE 4 60 #define TCPOLEN_MPTCP_DSS_ACK32 4 61 #define TCPOLEN_MPTCP_DSS_ACK64 8 62 #define TCPOLEN_MPTCP_DSS_MAP32 10 63 #define TCPOLEN_MPTCP_DSS_MAP64 14 64 #define TCPOLEN_MPTCP_DSS_CHECKSUM 2 65 #define TCPOLEN_MPTCP_ADD_ADDR 16 66 #define TCPOLEN_MPTCP_ADD_ADDR_PORT 18 67 #define TCPOLEN_MPTCP_ADD_ADDR_BASE 8 68 #define TCPOLEN_MPTCP_ADD_ADDR_BASE_PORT 10 69 #define TCPOLEN_MPTCP_ADD_ADDR6 28 70 #define TCPOLEN_MPTCP_ADD_ADDR6_PORT 30 71 #define TCPOLEN_MPTCP_ADD_ADDR6_BASE 20 72 #define TCPOLEN_MPTCP_ADD_ADDR6_BASE_PORT 22 73 #define TCPOLEN_MPTCP_PORT_LEN 2 74 #define TCPOLEN_MPTCP_PORT_ALIGN 2 75 #define TCPOLEN_MPTCP_RM_ADDR_BASE 3 76 #define TCPOLEN_MPTCP_PRIO 3 77 #define TCPOLEN_MPTCP_PRIO_ALIGN 4 78 #define TCPOLEN_MPTCP_FASTCLOSE 12 79 #define TCPOLEN_MPTCP_RST 4 80 #define TCPOLEN_MPTCP_FAIL 12 81 82 #define TCPOLEN_MPTCP_MPC_ACK_DATA_CSUM (TCPOLEN_MPTCP_DSS_CHECKSUM + TCPOLEN_MPTCP_MPC_ACK_DATA) 83 84 /* MPTCP MP_JOIN flags */ 85 #define MPTCPOPT_BACKUP BIT(0) 86 #define MPTCPOPT_THMAC_LEN 8 87 88 /* MPTCP MP_CAPABLE flags */ 89 #define MPTCP_VERSION_MASK (0x0F) 90 #define MPTCP_CAP_CHECKSUM_REQD BIT(7) 91 #define MPTCP_CAP_EXTENSIBILITY BIT(6) 92 #define MPTCP_CAP_DENY_JOIN_ID0 BIT(5) 93 #define MPTCP_CAP_HMAC_SHA256 BIT(0) 94 #define MPTCP_CAP_FLAG_MASK (0x1F) 95 96 /* MPTCP DSS flags */ 97 #define MPTCP_DSS_DATA_FIN BIT(4) 98 #define MPTCP_DSS_DSN64 BIT(3) 99 #define MPTCP_DSS_HAS_MAP BIT(2) 100 #define MPTCP_DSS_ACK64 BIT(1) 101 #define MPTCP_DSS_HAS_ACK BIT(0) 102 #define MPTCP_DSS_FLAG_MASK (0x1F) 103 104 /* MPTCP ADD_ADDR flags */ 105 #define MPTCP_ADDR_ECHO BIT(0) 106 107 /* MPTCP MP_PRIO flags */ 108 #define MPTCP_PRIO_BKUP BIT(0) 109 110 /* MPTCP TCPRST flags */ 111 #define MPTCP_RST_TRANSIENT BIT(0) 112 113 /* MPTCP socket atomic flags */ 114 #define MPTCP_NOSPACE 1 115 #define MPTCP_WORK_RTX 2 116 #define MPTCP_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 enum mptcp_pm_type { 187 MPTCP_PM_TYPE_KERNEL = 0, 188 MPTCP_PM_TYPE_USERSPACE, 189 190 __MPTCP_PM_TYPE_NR, 191 __MPTCP_PM_TYPE_MAX = __MPTCP_PM_TYPE_NR - 1, 192 }; 193 194 /* Status bits below MPTCP_PM_ALREADY_ESTABLISHED need pm worker actions */ 195 #define MPTCP_PM_WORK_MASK ((1 << MPTCP_PM_ALREADY_ESTABLISHED) - 1) 196 197 enum mptcp_addr_signal_status { 198 MPTCP_ADD_ADDR_SIGNAL, 199 MPTCP_ADD_ADDR_ECHO, 200 MPTCP_RM_ADDR_SIGNAL, 201 }; 202 203 /* max value of mptcp_addr_info.id */ 204 #define MPTCP_PM_MAX_ADDR_ID U8_MAX 205 206 struct mptcp_pm_data { 207 struct mptcp_addr_info local; 208 struct mptcp_addr_info remote; 209 struct list_head anno_list; 210 struct list_head userspace_pm_local_addr_list; 211 212 spinlock_t lock; /*protects the whole PM data */ 213 214 u8 addr_signal; 215 bool server_side; 216 bool work_pending; 217 bool accept_addr; 218 bool accept_subflow; 219 bool remote_deny_join_id0; 220 u8 add_addr_signaled; 221 u8 add_addr_accepted; 222 u8 local_addr_used; 223 u8 pm_type; 224 u8 subflows; 225 u8 status; 226 DECLARE_BITMAP(id_avail_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); 227 struct mptcp_rm_list rm_list_tx; 228 struct mptcp_rm_list rm_list_rx; 229 }; 230 231 struct mptcp_pm_addr_entry { 232 struct list_head list; 233 struct mptcp_addr_info addr; 234 u8 flags; 235 int ifindex; 236 struct socket *lsk; 237 }; 238 239 struct mptcp_data_frag { 240 struct list_head list; 241 u64 data_seq; 242 u16 data_len; 243 u16 offset; 244 u16 overhead; 245 u16 already_sent; 246 struct page *page; 247 }; 248 249 /* MPTCP connection sock */ 250 struct mptcp_sock { 251 /* inet_connection_sock must be the first member */ 252 struct inet_connection_sock sk; 253 u64 local_key; 254 u64 remote_key; 255 u64 write_seq; 256 u64 snd_nxt; 257 u64 ack_seq; 258 atomic64_t rcv_wnd_sent; 259 u64 rcv_data_fin_seq; 260 int rmem_fwd_alloc; 261 struct sock *last_snd; 262 int snd_burst; 263 int old_wspace; 264 u64 recovery_snd_nxt; /* in recovery mode accept up to this seq; 265 * recovery related fields are under data_lock 266 * protection 267 */ 268 u64 snd_una; 269 u64 wnd_end; 270 unsigned long timer_ival; 271 u32 token; 272 int rmem_released; 273 unsigned long flags; 274 unsigned long cb_flags; 275 unsigned long push_pending; 276 bool recovery; /* closing subflow write queue reinjected */ 277 bool can_ack; 278 bool fully_established; 279 bool rcv_data_fin; 280 bool snd_data_fin_enable; 281 bool rcv_fastclose; 282 bool use_64bit_ack; /* Set when we received a 64-bit DSN */ 283 bool csum_enabled; 284 bool allow_infinite_fallback; 285 u8 mpc_endpoint_id; 286 u8 recvmsg_inq:1, 287 cork:1, 288 nodelay:1; 289 struct work_struct work; 290 struct sk_buff *ooo_last_skb; 291 struct rb_root out_of_order_queue; 292 struct sk_buff_head receive_queue; 293 struct list_head conn_list; 294 struct list_head rtx_queue; 295 struct mptcp_data_frag *first_pending; 296 struct list_head join_list; 297 struct socket *subflow; /* outgoing connect/listener/!mp_capable */ 298 struct sock *first; 299 struct mptcp_pm_data pm; 300 struct { 301 u32 space; /* bytes copied in last measurement window */ 302 u32 copied; /* bytes copied in this measurement window */ 303 u64 time; /* start time of measurement window */ 304 u64 rtt_us; /* last maximum rtt of subflows */ 305 } rcvq_space; 306 307 u32 setsockopt_seq; 308 char ca_name[TCP_CA_NAME_MAX]; 309 struct mptcp_sock *dl_next; 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 #define mptcp_for_each_subflow_safe(__msk, __subflow, __tmp) \ 318 list_for_each_entry_safe(__subflow, __tmp, &((__msk)->conn_list), node) 319 320 static inline void msk_owned_by_me(const struct mptcp_sock *msk) 321 { 322 sock_owned_by_me((const struct sock *)msk); 323 } 324 325 static inline struct mptcp_sock *mptcp_sk(const struct sock *sk) 326 { 327 return (struct mptcp_sock *)sk; 328 } 329 330 /* the msk socket don't use the backlog, also account for the bulk 331 * free memory 332 */ 333 static inline int __mptcp_rmem(const struct sock *sk) 334 { 335 return atomic_read(&sk->sk_rmem_alloc) - READ_ONCE(mptcp_sk(sk)->rmem_released); 336 } 337 338 static inline int __mptcp_space(const struct sock *sk) 339 { 340 return tcp_win_from_space(sk, READ_ONCE(sk->sk_rcvbuf) - __mptcp_rmem(sk)); 341 } 342 343 static inline struct mptcp_data_frag *mptcp_send_head(const struct sock *sk) 344 { 345 const struct mptcp_sock *msk = mptcp_sk(sk); 346 347 return READ_ONCE(msk->first_pending); 348 } 349 350 static inline struct mptcp_data_frag *mptcp_send_next(struct sock *sk) 351 { 352 struct mptcp_sock *msk = mptcp_sk(sk); 353 struct mptcp_data_frag *cur; 354 355 cur = msk->first_pending; 356 return list_is_last(&cur->list, &msk->rtx_queue) ? NULL : 357 list_next_entry(cur, list); 358 } 359 360 static inline struct mptcp_data_frag *mptcp_pending_tail(const struct sock *sk) 361 { 362 struct mptcp_sock *msk = mptcp_sk(sk); 363 364 if (!msk->first_pending) 365 return NULL; 366 367 if (WARN_ON_ONCE(list_empty(&msk->rtx_queue))) 368 return NULL; 369 370 return list_last_entry(&msk->rtx_queue, struct mptcp_data_frag, list); 371 } 372 373 static inline struct mptcp_data_frag *mptcp_rtx_head(const struct sock *sk) 374 { 375 struct mptcp_sock *msk = mptcp_sk(sk); 376 377 if (msk->snd_una == READ_ONCE(msk->snd_nxt)) 378 return NULL; 379 380 return list_first_entry_or_null(&msk->rtx_queue, struct mptcp_data_frag, list); 381 } 382 383 struct csum_pseudo_header { 384 __be64 data_seq; 385 __be32 subflow_seq; 386 __be16 data_len; 387 __sum16 csum; 388 }; 389 390 struct mptcp_subflow_request_sock { 391 struct tcp_request_sock sk; 392 u16 mp_capable : 1, 393 mp_join : 1, 394 backup : 1, 395 csum_reqd : 1, 396 allow_join_id0 : 1; 397 u8 local_id; 398 u8 remote_id; 399 u64 local_key; 400 u64 idsn; 401 u32 token; 402 u32 ssn_offset; 403 u64 thmac; 404 u32 local_nonce; 405 u32 remote_nonce; 406 struct mptcp_sock *msk; 407 struct hlist_nulls_node token_node; 408 }; 409 410 static inline struct mptcp_subflow_request_sock * 411 mptcp_subflow_rsk(const struct request_sock *rsk) 412 { 413 return (struct mptcp_subflow_request_sock *)rsk; 414 } 415 416 enum mptcp_data_avail { 417 MPTCP_SUBFLOW_NODATA, 418 MPTCP_SUBFLOW_DATA_AVAIL, 419 }; 420 421 struct mptcp_delegated_action { 422 struct napi_struct napi; 423 struct list_head head; 424 }; 425 426 DECLARE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions); 427 428 #define MPTCP_DELEGATE_SEND 0 429 #define MPTCP_DELEGATE_ACK 1 430 431 /* MPTCP subflow context */ 432 struct mptcp_subflow_context { 433 struct list_head node;/* conn_list of subflows */ 434 435 struct_group(reset, 436 437 unsigned long avg_pacing_rate; /* protected by msk socket lock */ 438 u64 local_key; 439 u64 remote_key; 440 u64 idsn; 441 u64 map_seq; 442 u32 snd_isn; 443 u32 token; 444 u32 rel_write_seq; 445 u32 map_subflow_seq; 446 u32 ssn_offset; 447 u32 map_data_len; 448 __wsum map_data_csum; 449 u32 map_csum_len; 450 u32 request_mptcp : 1, /* send MP_CAPABLE */ 451 request_join : 1, /* send MP_JOIN */ 452 request_bkup : 1, 453 mp_capable : 1, /* remote is MPTCP capable */ 454 mp_join : 1, /* remote is JOINing */ 455 fully_established : 1, /* path validated */ 456 pm_notified : 1, /* PM hook called for established status */ 457 conn_finished : 1, 458 map_valid : 1, 459 map_csum_reqd : 1, 460 map_data_fin : 1, 461 mpc_map : 1, 462 backup : 1, 463 send_mp_prio : 1, 464 send_mp_fail : 1, 465 send_fastclose : 1, 466 send_infinite_map : 1, 467 rx_eof : 1, 468 can_ack : 1, /* only after processing the remote a key */ 469 disposable : 1, /* ctx can be free at ulp release time */ 470 stale : 1, /* unable to snd/rcv data, do not use for xmit */ 471 local_id_valid : 1, /* local_id is correctly initialized */ 472 valid_csum_seen : 1; /* at least one csum validated */ 473 enum mptcp_data_avail data_avail; 474 u32 remote_nonce; 475 u64 thmac; 476 u32 local_nonce; 477 u32 remote_token; 478 u8 hmac[MPTCPOPT_HMAC_LEN]; 479 u8 local_id; 480 u8 remote_id; 481 u8 reset_seen:1; 482 u8 reset_transient:1; 483 u8 reset_reason:4; 484 u8 stale_count; 485 486 long delegated_status; 487 unsigned long fail_tout; 488 489 ); 490 491 struct list_head delegated_node; /* link into delegated_action, protected by local BH */ 492 493 u32 setsockopt_seq; 494 u32 stale_rcv_tstamp; 495 496 struct sock *tcp_sock; /* tcp sk backpointer */ 497 struct sock *conn; /* parent mptcp_sock */ 498 const struct inet_connection_sock_af_ops *icsk_af_ops; 499 void (*tcp_state_change)(struct sock *sk); 500 void (*tcp_error_report)(struct sock *sk); 501 502 struct rcu_head rcu; 503 }; 504 505 static inline struct mptcp_subflow_context * 506 mptcp_subflow_ctx(const struct sock *sk) 507 { 508 struct inet_connection_sock *icsk = inet_csk(sk); 509 510 /* Use RCU on icsk_ulp_data only for sock diag code */ 511 return (__force struct mptcp_subflow_context *)icsk->icsk_ulp_data; 512 } 513 514 static inline struct sock * 515 mptcp_subflow_tcp_sock(const struct mptcp_subflow_context *subflow) 516 { 517 return subflow->tcp_sock; 518 } 519 520 static inline void 521 mptcp_subflow_ctx_reset(struct mptcp_subflow_context *subflow) 522 { 523 memset(&subflow->reset, 0, sizeof(subflow->reset)); 524 subflow->request_mptcp = 1; 525 } 526 527 static inline u64 528 mptcp_subflow_get_map_offset(const struct mptcp_subflow_context *subflow) 529 { 530 return tcp_sk(mptcp_subflow_tcp_sock(subflow))->copied_seq - 531 subflow->ssn_offset - 532 subflow->map_subflow_seq; 533 } 534 535 static inline u64 536 mptcp_subflow_get_mapped_dsn(const struct mptcp_subflow_context *subflow) 537 { 538 return subflow->map_seq + mptcp_subflow_get_map_offset(subflow); 539 } 540 541 void mptcp_subflow_process_delegated(struct sock *ssk); 542 543 static inline void mptcp_subflow_delegate(struct mptcp_subflow_context *subflow, int action) 544 { 545 struct mptcp_delegated_action *delegated; 546 bool schedule; 547 548 /* the caller held the subflow bh socket lock */ 549 lockdep_assert_in_softirq(); 550 551 /* The implied barrier pairs with mptcp_subflow_delegated_done(), and 552 * ensures the below list check sees list updates done prior to status 553 * bit changes 554 */ 555 if (!test_and_set_bit(action, &subflow->delegated_status)) { 556 /* still on delegated list from previous scheduling */ 557 if (!list_empty(&subflow->delegated_node)) 558 return; 559 560 delegated = this_cpu_ptr(&mptcp_delegated_actions); 561 schedule = list_empty(&delegated->head); 562 list_add_tail(&subflow->delegated_node, &delegated->head); 563 sock_hold(mptcp_subflow_tcp_sock(subflow)); 564 if (schedule) 565 napi_schedule(&delegated->napi); 566 } 567 } 568 569 static inline struct mptcp_subflow_context * 570 mptcp_subflow_delegated_next(struct mptcp_delegated_action *delegated) 571 { 572 struct mptcp_subflow_context *ret; 573 574 if (list_empty(&delegated->head)) 575 return NULL; 576 577 ret = list_first_entry(&delegated->head, struct mptcp_subflow_context, delegated_node); 578 list_del_init(&ret->delegated_node); 579 return ret; 580 } 581 582 static inline bool mptcp_subflow_has_delegated_action(const struct mptcp_subflow_context *subflow) 583 { 584 return !!READ_ONCE(subflow->delegated_status); 585 } 586 587 static inline void mptcp_subflow_delegated_done(struct mptcp_subflow_context *subflow, int action) 588 { 589 /* pairs with mptcp_subflow_delegate, ensures delegate_node is updated before 590 * touching the status bit 591 */ 592 smp_wmb(); 593 clear_bit(action, &subflow->delegated_status); 594 } 595 596 int mptcp_is_enabled(const struct net *net); 597 unsigned int mptcp_get_add_addr_timeout(const struct net *net); 598 int mptcp_is_checksum_enabled(const struct net *net); 599 int mptcp_allow_join_id0(const struct net *net); 600 unsigned int mptcp_stale_loss_cnt(const struct net *net); 601 int mptcp_get_pm_type(const struct net *net); 602 void mptcp_subflow_fully_established(struct mptcp_subflow_context *subflow, 603 struct mptcp_options_received *mp_opt); 604 bool __mptcp_retransmit_pending_data(struct sock *sk); 605 void mptcp_check_and_set_pending(struct sock *sk); 606 void __mptcp_push_pending(struct sock *sk, unsigned int flags); 607 bool mptcp_subflow_data_available(struct sock *sk); 608 void __init mptcp_subflow_init(void); 609 void mptcp_subflow_shutdown(struct sock *sk, struct sock *ssk, int how); 610 void mptcp_close_ssk(struct sock *sk, struct sock *ssk, 611 struct mptcp_subflow_context *subflow); 612 void __mptcp_subflow_send_ack(struct sock *ssk); 613 void mptcp_subflow_reset(struct sock *ssk); 614 void mptcp_subflow_queue_clean(struct sock *ssk); 615 void mptcp_sock_graft(struct sock *sk, struct socket *parent); 616 struct socket *__mptcp_nmpc_socket(const struct mptcp_sock *msk); 617 bool __mptcp_close(struct sock *sk, long timeout); 618 void mptcp_cancel_work(struct sock *sk); 619 620 bool mptcp_addresses_equal(const struct mptcp_addr_info *a, 621 const struct mptcp_addr_info *b, bool use_port); 622 623 /* called with sk socket lock held */ 624 int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_addr_info *loc, 625 const struct mptcp_addr_info *remote); 626 int mptcp_subflow_create_socket(struct sock *sk, struct socket **new_sock); 627 void mptcp_info2sockaddr(const struct mptcp_addr_info *info, 628 struct sockaddr_storage *addr, 629 unsigned short family); 630 631 static inline bool __tcp_can_send(const struct sock *ssk) 632 { 633 /* only send if our side has not closed yet */ 634 return ((1 << inet_sk_state_load(ssk)) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)); 635 } 636 637 static inline bool __mptcp_subflow_active(struct mptcp_subflow_context *subflow) 638 { 639 /* can't send if JOIN hasn't completed yet (i.e. is usable for mptcp) */ 640 if (subflow->request_join && !subflow->fully_established) 641 return false; 642 643 return __tcp_can_send(mptcp_subflow_tcp_sock(subflow)); 644 } 645 646 void mptcp_subflow_set_active(struct mptcp_subflow_context *subflow); 647 648 bool mptcp_subflow_active(struct mptcp_subflow_context *subflow); 649 650 static inline void mptcp_subflow_tcp_fallback(struct sock *sk, 651 struct mptcp_subflow_context *ctx) 652 { 653 sk->sk_data_ready = sock_def_readable; 654 sk->sk_state_change = ctx->tcp_state_change; 655 sk->sk_write_space = sk_stream_write_space; 656 sk->sk_error_report = ctx->tcp_error_report; 657 658 inet_csk(sk)->icsk_af_ops = ctx->icsk_af_ops; 659 } 660 661 void __init mptcp_proto_init(void); 662 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 663 int __init mptcp_proto_v6_init(void); 664 #endif 665 666 struct sock *mptcp_sk_clone(const struct sock *sk, 667 const struct mptcp_options_received *mp_opt, 668 struct request_sock *req); 669 void mptcp_get_options(const struct sk_buff *skb, 670 struct mptcp_options_received *mp_opt); 671 672 void mptcp_finish_connect(struct sock *sk); 673 void __mptcp_set_connected(struct sock *sk); 674 void mptcp_reset_timeout(struct mptcp_sock *msk, unsigned long fail_tout); 675 static inline bool mptcp_is_fully_established(struct sock *sk) 676 { 677 return inet_sk_state_load(sk) == TCP_ESTABLISHED && 678 READ_ONCE(mptcp_sk(sk)->fully_established); 679 } 680 void mptcp_rcv_space_init(struct mptcp_sock *msk, const struct sock *ssk); 681 void mptcp_data_ready(struct sock *sk, struct sock *ssk); 682 bool mptcp_finish_join(struct sock *sk); 683 bool mptcp_schedule_work(struct sock *sk); 684 int mptcp_setsockopt(struct sock *sk, int level, int optname, 685 sockptr_t optval, unsigned int optlen); 686 int mptcp_getsockopt(struct sock *sk, int level, int optname, 687 char __user *optval, int __user *option); 688 689 u64 __mptcp_expand_seq(u64 old_seq, u64 cur_seq); 690 static inline u64 mptcp_expand_seq(u64 old_seq, u64 cur_seq, bool use_64bit) 691 { 692 if (use_64bit) 693 return cur_seq; 694 695 return __mptcp_expand_seq(old_seq, cur_seq); 696 } 697 void __mptcp_check_push(struct sock *sk, struct sock *ssk); 698 void __mptcp_data_acked(struct sock *sk); 699 void __mptcp_error_report(struct sock *sk); 700 void mptcp_subflow_eof(struct sock *sk); 701 bool mptcp_update_rcv_data_fin(struct mptcp_sock *msk, u64 data_fin_seq, bool use_64bit); 702 static inline bool mptcp_data_fin_enabled(const struct mptcp_sock *msk) 703 { 704 return READ_ONCE(msk->snd_data_fin_enable) && 705 READ_ONCE(msk->write_seq) == READ_ONCE(msk->snd_nxt); 706 } 707 708 static inline bool mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk) 709 { 710 if ((sk->sk_userlocks & SOCK_SNDBUF_LOCK) || ssk->sk_sndbuf <= READ_ONCE(sk->sk_sndbuf)) 711 return false; 712 713 WRITE_ONCE(sk->sk_sndbuf, ssk->sk_sndbuf); 714 return true; 715 } 716 717 static inline void mptcp_write_space(struct sock *sk) 718 { 719 if (sk_stream_is_writeable(sk)) { 720 /* pairs with memory barrier in mptcp_poll */ 721 smp_mb(); 722 if (test_and_clear_bit(MPTCP_NOSPACE, &mptcp_sk(sk)->flags)) 723 sk_stream_write_space(sk); 724 } 725 } 726 727 void mptcp_destroy_common(struct mptcp_sock *msk, unsigned int flags); 728 729 #define MPTCP_TOKEN_MAX_RETRIES 4 730 731 void __init mptcp_token_init(void); 732 static inline void mptcp_token_init_request(struct request_sock *req) 733 { 734 mptcp_subflow_rsk(req)->token_node.pprev = NULL; 735 } 736 737 int mptcp_token_new_request(struct request_sock *req); 738 void mptcp_token_destroy_request(struct request_sock *req); 739 int mptcp_token_new_connect(struct sock *sk); 740 void mptcp_token_accept(struct mptcp_subflow_request_sock *r, 741 struct mptcp_sock *msk); 742 bool mptcp_token_exists(u32 token); 743 struct mptcp_sock *mptcp_token_get_sock(struct net *net, u32 token); 744 struct mptcp_sock *mptcp_token_iter_next(const struct net *net, long *s_slot, 745 long *s_num); 746 void mptcp_token_destroy(struct mptcp_sock *msk); 747 748 void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn); 749 750 void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u8 *msg, int len, void *hmac); 751 __sum16 __mptcp_make_csum(u64 data_seq, u32 subflow_seq, u16 data_len, __wsum sum); 752 753 void __init mptcp_pm_init(void); 754 void mptcp_pm_data_init(struct mptcp_sock *msk); 755 void mptcp_pm_data_reset(struct mptcp_sock *msk); 756 int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info, 757 struct mptcp_addr_info *addr); 758 int mptcp_pm_parse_entry(struct nlattr *attr, struct genl_info *info, 759 bool require_family, 760 struct mptcp_pm_addr_entry *entry); 761 void mptcp_pm_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); 762 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); 763 void mptcp_pm_new_connection(struct mptcp_sock *msk, const struct sock *ssk, int server_side); 764 void mptcp_pm_fully_established(struct mptcp_sock *msk, const struct sock *ssk, gfp_t gfp); 765 bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk); 766 void mptcp_pm_connection_closed(struct mptcp_sock *msk); 767 void mptcp_pm_subflow_established(struct mptcp_sock *msk); 768 bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk); 769 void mptcp_pm_subflow_check_next(struct mptcp_sock *msk, const struct sock *ssk, 770 const struct mptcp_subflow_context *subflow); 771 void mptcp_pm_add_addr_received(const struct sock *ssk, 772 const struct mptcp_addr_info *addr); 773 void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk, 774 const struct mptcp_addr_info *addr); 775 void mptcp_pm_add_addr_send_ack(struct mptcp_sock *msk); 776 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk); 777 void mptcp_pm_rm_addr_received(struct mptcp_sock *msk, 778 const struct mptcp_rm_list *rm_list); 779 void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup); 780 void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq); 781 int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk, 782 struct mptcp_addr_info *addr, 783 struct mptcp_addr_info *rem, 784 u8 bkup); 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 int mptcp_userspace_pm_set_flags(struct net *net, struct nlattr *token, 802 struct mptcp_pm_addr_entry *loc, 803 struct mptcp_pm_addr_entry *rem, u8 bkup); 804 int mptcp_pm_announce_addr(struct mptcp_sock *msk, 805 const struct mptcp_addr_info *addr, 806 bool echo); 807 int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); 808 int mptcp_pm_remove_subflow(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); 809 void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk, 810 struct list_head *rm_list); 811 812 int mptcp_userspace_pm_append_new_local_addr(struct mptcp_sock *msk, 813 struct mptcp_pm_addr_entry *entry); 814 void mptcp_free_local_addr_list(struct mptcp_sock *msk); 815 int mptcp_nl_cmd_announce(struct sk_buff *skb, struct genl_info *info); 816 int mptcp_nl_cmd_remove(struct sk_buff *skb, struct genl_info *info); 817 int mptcp_nl_cmd_sf_create(struct sk_buff *skb, struct genl_info *info); 818 int mptcp_nl_cmd_sf_destroy(struct sk_buff *skb, struct genl_info *info); 819 820 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk, 821 const struct sock *ssk, gfp_t gfp); 822 void mptcp_event_addr_announced(const struct sock *ssk, const struct mptcp_addr_info *info); 823 void mptcp_event_addr_removed(const struct mptcp_sock *msk, u8 id); 824 bool mptcp_userspace_pm_active(const struct mptcp_sock *msk); 825 826 static inline bool mptcp_pm_should_add_signal(struct mptcp_sock *msk) 827 { 828 return READ_ONCE(msk->pm.addr_signal) & 829 (BIT(MPTCP_ADD_ADDR_SIGNAL) | BIT(MPTCP_ADD_ADDR_ECHO)); 830 } 831 832 static inline bool mptcp_pm_should_add_signal_addr(struct mptcp_sock *msk) 833 { 834 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_SIGNAL); 835 } 836 837 static inline bool mptcp_pm_should_add_signal_echo(struct mptcp_sock *msk) 838 { 839 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_ECHO); 840 } 841 842 static inline bool mptcp_pm_should_rm_signal(struct mptcp_sock *msk) 843 { 844 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_RM_ADDR_SIGNAL); 845 } 846 847 static inline bool mptcp_pm_is_userspace(const struct mptcp_sock *msk) 848 { 849 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_USERSPACE; 850 } 851 852 static inline bool mptcp_pm_is_kernel(const struct mptcp_sock *msk) 853 { 854 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_KERNEL; 855 } 856 857 static inline unsigned int mptcp_add_addr_len(int family, bool echo, bool port) 858 { 859 u8 len = TCPOLEN_MPTCP_ADD_ADDR_BASE; 860 861 if (family == AF_INET6) 862 len = TCPOLEN_MPTCP_ADD_ADDR6_BASE; 863 if (!echo) 864 len += MPTCPOPT_THMAC_LEN; 865 /* account for 2 trailing 'nop' options */ 866 if (port) 867 len += TCPOLEN_MPTCP_PORT_LEN + TCPOLEN_MPTCP_PORT_ALIGN; 868 869 return len; 870 } 871 872 static inline int mptcp_rm_addr_len(const struct mptcp_rm_list *rm_list) 873 { 874 if (rm_list->nr == 0 || rm_list->nr > MPTCP_RM_IDS_MAX) 875 return -EINVAL; 876 877 return TCPOLEN_MPTCP_RM_ADDR_BASE + roundup(rm_list->nr - 1, 4) + 1; 878 } 879 880 bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, const struct sk_buff *skb, 881 unsigned int opt_size, unsigned int remaining, 882 struct mptcp_addr_info *addr, bool *echo, 883 bool *drop_other_suboptions); 884 bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining, 885 struct mptcp_rm_list *rm_list); 886 int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc); 887 int mptcp_userspace_pm_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc); 888 889 void __init mptcp_pm_nl_init(void); 890 void mptcp_pm_nl_work(struct mptcp_sock *msk); 891 void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk, 892 const struct mptcp_rm_list *rm_list); 893 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct sock_common *skc); 894 unsigned int mptcp_pm_get_add_addr_signal_max(const struct mptcp_sock *msk); 895 unsigned int mptcp_pm_get_add_addr_accept_max(const struct mptcp_sock *msk); 896 unsigned int mptcp_pm_get_subflows_max(const struct mptcp_sock *msk); 897 unsigned int mptcp_pm_get_local_addr_max(const struct mptcp_sock *msk); 898 899 /* called under PM lock */ 900 static inline void __mptcp_pm_close_subflow(struct mptcp_sock *msk) 901 { 902 if (--msk->pm.subflows < mptcp_pm_get_subflows_max(msk)) 903 WRITE_ONCE(msk->pm.accept_subflow, true); 904 } 905 906 static inline void mptcp_pm_close_subflow(struct mptcp_sock *msk) 907 { 908 spin_lock_bh(&msk->pm.lock); 909 __mptcp_pm_close_subflow(msk); 910 spin_unlock_bh(&msk->pm.lock); 911 } 912 913 void mptcp_sockopt_sync(struct mptcp_sock *msk, struct sock *ssk); 914 void mptcp_sockopt_sync_locked(struct mptcp_sock *msk, struct sock *ssk); 915 916 static inline struct mptcp_ext *mptcp_get_ext(const struct sk_buff *skb) 917 { 918 return (struct mptcp_ext *)skb_ext_find(skb, SKB_EXT_MPTCP); 919 } 920 921 void mptcp_diag_subflow_init(struct tcp_ulp_ops *ops); 922 923 static inline bool __mptcp_check_fallback(const struct mptcp_sock *msk) 924 { 925 return test_bit(MPTCP_FALLBACK_DONE, &msk->flags); 926 } 927 928 static inline bool mptcp_check_fallback(const struct sock *sk) 929 { 930 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 931 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 932 933 return __mptcp_check_fallback(msk); 934 } 935 936 static inline void __mptcp_do_fallback(struct mptcp_sock *msk) 937 { 938 if (test_bit(MPTCP_FALLBACK_DONE, &msk->flags)) { 939 pr_debug("TCP fallback already done (msk=%p)", msk); 940 return; 941 } 942 set_bit(MPTCP_FALLBACK_DONE, &msk->flags); 943 } 944 945 static inline void mptcp_do_fallback(struct sock *ssk) 946 { 947 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 948 struct sock *sk = subflow->conn; 949 struct mptcp_sock *msk; 950 951 msk = mptcp_sk(sk); 952 __mptcp_do_fallback(msk); 953 if (READ_ONCE(msk->snd_data_fin_enable) && !(ssk->sk_shutdown & SEND_SHUTDOWN)) { 954 gfp_t saved_allocation = ssk->sk_allocation; 955 956 /* we are in a atomic (BH) scope, override ssk default for data 957 * fin allocation 958 */ 959 ssk->sk_allocation = GFP_ATOMIC; 960 ssk->sk_shutdown |= SEND_SHUTDOWN; 961 tcp_shutdown(ssk, SEND_SHUTDOWN); 962 ssk->sk_allocation = saved_allocation; 963 } 964 } 965 966 #define pr_fallback(a) pr_debug("%s:fallback to TCP (msk=%p)", __func__, a) 967 968 static inline bool mptcp_check_infinite_map(struct sk_buff *skb) 969 { 970 struct mptcp_ext *mpext; 971 972 mpext = skb ? mptcp_get_ext(skb) : NULL; 973 if (mpext && mpext->infinite_map) 974 return true; 975 976 return false; 977 } 978 979 static inline bool is_active_ssk(struct mptcp_subflow_context *subflow) 980 { 981 return (subflow->request_mptcp || subflow->request_join); 982 } 983 984 static inline bool subflow_simultaneous_connect(struct sock *sk) 985 { 986 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 987 988 return sk->sk_state == TCP_ESTABLISHED && 989 is_active_ssk(subflow) && 990 !subflow->conn_finished; 991 } 992 993 #ifdef CONFIG_SYN_COOKIES 994 void subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 995 struct sk_buff *skb); 996 bool mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 997 struct sk_buff *skb); 998 void __init mptcp_join_cookie_init(void); 999 #else 1000 static inline void 1001 subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 1002 struct sk_buff *skb) {} 1003 static inline bool 1004 mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 1005 struct sk_buff *skb) 1006 { 1007 return false; 1008 } 1009 1010 static inline void mptcp_join_cookie_init(void) {} 1011 #endif 1012 1013 #endif /* __MPTCP_PROTOCOL_H */ 1014