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_FALLBACK_DONE 4 117 #define MPTCP_WORK_CLOSE_SUBFLOW 5 118 119 /* MPTCP socket release cb flags */ 120 #define MPTCP_PUSH_PENDING 1 121 #define MPTCP_CLEAN_UNA 2 122 #define MPTCP_ERROR_REPORT 3 123 #define MPTCP_RETRANSMIT 4 124 #define MPTCP_FLUSH_JOIN_LIST 5 125 #define MPTCP_CONNECTED 6 126 #define MPTCP_RESET_SCHEDULER 7 127 128 struct mptcp_skb_cb { 129 u64 map_seq; 130 u64 end_seq; 131 u32 offset; 132 u8 has_rxtstamp:1; 133 }; 134 135 #define MPTCP_SKB_CB(__skb) ((struct mptcp_skb_cb *)&((__skb)->cb[0])) 136 137 static inline bool before64(__u64 seq1, __u64 seq2) 138 { 139 return (__s64)(seq1 - seq2) < 0; 140 } 141 142 #define after64(seq2, seq1) before64(seq1, seq2) 143 144 struct mptcp_options_received { 145 u64 sndr_key; 146 u64 rcvr_key; 147 u64 data_ack; 148 u64 data_seq; 149 u32 subflow_seq; 150 u16 data_len; 151 __sum16 csum; 152 u16 suboptions; 153 u32 token; 154 u32 nonce; 155 u16 use_map:1, 156 dsn64:1, 157 data_fin:1, 158 use_ack:1, 159 ack64:1, 160 mpc_map:1, 161 reset_reason:4, 162 reset_transient:1, 163 echo:1, 164 backup:1, 165 deny_join_id0:1, 166 __unused:2; 167 u8 join_id; 168 u64 thmac; 169 u8 hmac[MPTCPOPT_HMAC_LEN]; 170 struct mptcp_addr_info addr; 171 struct mptcp_rm_list rm_list; 172 u64 ahmac; 173 u64 fail_seq; 174 }; 175 176 static inline __be32 mptcp_option(u8 subopt, u8 len, u8 nib, u8 field) 177 { 178 return htonl((TCPOPT_MPTCP << 24) | (len << 16) | (subopt << 12) | 179 ((nib & 0xF) << 8) | field); 180 } 181 182 enum mptcp_pm_status { 183 MPTCP_PM_ADD_ADDR_RECEIVED, 184 MPTCP_PM_ADD_ADDR_SEND_ACK, 185 MPTCP_PM_RM_ADDR_RECEIVED, 186 MPTCP_PM_ESTABLISHED, 187 MPTCP_PM_SUBFLOW_ESTABLISHED, 188 MPTCP_PM_ALREADY_ESTABLISHED, /* persistent status, set after ESTABLISHED event */ 189 MPTCP_PM_MPC_ENDPOINT_ACCOUNTED /* persistent status, set after MPC local address is 190 * accounted int id_avail_bitmap 191 */ 192 }; 193 194 enum mptcp_pm_type { 195 MPTCP_PM_TYPE_KERNEL = 0, 196 MPTCP_PM_TYPE_USERSPACE, 197 198 __MPTCP_PM_TYPE_NR, 199 __MPTCP_PM_TYPE_MAX = __MPTCP_PM_TYPE_NR - 1, 200 }; 201 202 /* Status bits below MPTCP_PM_ALREADY_ESTABLISHED need pm worker actions */ 203 #define MPTCP_PM_WORK_MASK ((1 << MPTCP_PM_ALREADY_ESTABLISHED) - 1) 204 205 enum mptcp_addr_signal_status { 206 MPTCP_ADD_ADDR_SIGNAL, 207 MPTCP_ADD_ADDR_ECHO, 208 MPTCP_RM_ADDR_SIGNAL, 209 }; 210 211 /* max value of mptcp_addr_info.id */ 212 #define MPTCP_PM_MAX_ADDR_ID U8_MAX 213 214 struct mptcp_pm_data { 215 struct mptcp_addr_info local; 216 struct mptcp_addr_info remote; 217 struct list_head anno_list; 218 struct list_head userspace_pm_local_addr_list; 219 220 spinlock_t lock; /*protects the whole PM data */ 221 222 u8 addr_signal; 223 bool server_side; 224 bool work_pending; 225 bool accept_addr; 226 bool accept_subflow; 227 bool remote_deny_join_id0; 228 u8 add_addr_signaled; 229 u8 add_addr_accepted; 230 u8 local_addr_used; 231 u8 pm_type; 232 u8 subflows; 233 u8 status; 234 DECLARE_BITMAP(id_avail_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); 235 struct mptcp_rm_list rm_list_tx; 236 struct mptcp_rm_list rm_list_rx; 237 }; 238 239 struct mptcp_pm_addr_entry { 240 struct list_head list; 241 struct mptcp_addr_info addr; 242 u8 flags; 243 int ifindex; 244 struct socket *lsk; 245 }; 246 247 struct mptcp_data_frag { 248 struct list_head list; 249 u64 data_seq; 250 u16 data_len; 251 u16 offset; 252 u16 overhead; 253 u16 already_sent; 254 struct page *page; 255 }; 256 257 /* MPTCP connection sock */ 258 struct mptcp_sock { 259 /* inet_connection_sock must be the first member */ 260 struct inet_connection_sock sk; 261 u64 local_key; 262 u64 remote_key; 263 u64 write_seq; 264 u64 bytes_sent; 265 u64 snd_nxt; 266 u64 bytes_received; 267 u64 ack_seq; 268 atomic64_t rcv_wnd_sent; 269 u64 rcv_data_fin_seq; 270 u64 bytes_retrans; 271 int rmem_fwd_alloc; 272 struct sock *last_snd; 273 int snd_burst; 274 int old_wspace; 275 u64 recovery_snd_nxt; /* in recovery mode accept up to this seq; 276 * recovery related fields are under data_lock 277 * protection 278 */ 279 u64 bytes_acked; 280 u64 snd_una; 281 u64 wnd_end; 282 unsigned long timer_ival; 283 u32 token; 284 int rmem_released; 285 unsigned long flags; 286 unsigned long cb_flags; 287 unsigned long push_pending; 288 bool recovery; /* closing subflow write queue reinjected */ 289 bool can_ack; 290 bool fully_established; 291 bool rcv_data_fin; 292 bool snd_data_fin_enable; 293 bool rcv_fastclose; 294 bool use_64bit_ack; /* Set when we received a 64-bit DSN */ 295 bool csum_enabled; 296 bool allow_infinite_fallback; 297 u8 mpc_endpoint_id; 298 u8 recvmsg_inq:1, 299 cork:1, 300 nodelay:1, 301 fastopening:1, 302 in_accept_queue:1; 303 struct work_struct work; 304 struct sk_buff *ooo_last_skb; 305 struct rb_root out_of_order_queue; 306 struct sk_buff_head receive_queue; 307 struct list_head conn_list; 308 struct list_head rtx_queue; 309 struct mptcp_data_frag *first_pending; 310 struct list_head join_list; 311 struct socket *subflow; /* outgoing connect/listener/!mp_capable 312 * The mptcp ops can safely dereference, using suitable 313 * ONCE annotation, the subflow outside the socket 314 * lock as such sock is freed after close(). 315 */ 316 struct sock *first; 317 struct mptcp_pm_data pm; 318 struct { 319 u32 space; /* bytes copied in last measurement window */ 320 u32 copied; /* bytes copied in this measurement window */ 321 u64 time; /* start time of measurement window */ 322 u64 rtt_us; /* last maximum rtt of subflows */ 323 } rcvq_space; 324 u8 scaling_ratio; 325 326 u32 subflow_id; 327 u32 setsockopt_seq; 328 char ca_name[TCP_CA_NAME_MAX]; 329 struct mptcp_sock *dl_next; 330 }; 331 332 #define mptcp_data_lock(sk) spin_lock_bh(&(sk)->sk_lock.slock) 333 #define mptcp_data_unlock(sk) spin_unlock_bh(&(sk)->sk_lock.slock) 334 335 #define mptcp_for_each_subflow(__msk, __subflow) \ 336 list_for_each_entry(__subflow, &((__msk)->conn_list), node) 337 #define mptcp_for_each_subflow_safe(__msk, __subflow, __tmp) \ 338 list_for_each_entry_safe(__subflow, __tmp, &((__msk)->conn_list), node) 339 340 static inline void msk_owned_by_me(const struct mptcp_sock *msk) 341 { 342 sock_owned_by_me((const struct sock *)msk); 343 } 344 345 #define mptcp_sk(ptr) container_of_const(ptr, struct mptcp_sock, sk.icsk_inet.sk) 346 347 /* the msk socket don't use the backlog, also account for the bulk 348 * free memory 349 */ 350 static inline int __mptcp_rmem(const struct sock *sk) 351 { 352 return atomic_read(&sk->sk_rmem_alloc) - READ_ONCE(mptcp_sk(sk)->rmem_released); 353 } 354 355 static inline int mptcp_win_from_space(const struct sock *sk, int space) 356 { 357 return __tcp_win_from_space(mptcp_sk(sk)->scaling_ratio, space); 358 } 359 360 static inline int __mptcp_space(const struct sock *sk) 361 { 362 return mptcp_win_from_space(sk, READ_ONCE(sk->sk_rcvbuf) - __mptcp_rmem(sk)); 363 } 364 365 static inline struct mptcp_data_frag *mptcp_send_head(const struct sock *sk) 366 { 367 const struct mptcp_sock *msk = mptcp_sk(sk); 368 369 return READ_ONCE(msk->first_pending); 370 } 371 372 static inline struct mptcp_data_frag *mptcp_send_next(struct sock *sk) 373 { 374 struct mptcp_sock *msk = mptcp_sk(sk); 375 struct mptcp_data_frag *cur; 376 377 cur = msk->first_pending; 378 return list_is_last(&cur->list, &msk->rtx_queue) ? NULL : 379 list_next_entry(cur, list); 380 } 381 382 static inline struct mptcp_data_frag *mptcp_pending_tail(const struct sock *sk) 383 { 384 const struct mptcp_sock *msk = mptcp_sk(sk); 385 386 if (!msk->first_pending) 387 return NULL; 388 389 if (WARN_ON_ONCE(list_empty(&msk->rtx_queue))) 390 return NULL; 391 392 return list_last_entry(&msk->rtx_queue, struct mptcp_data_frag, list); 393 } 394 395 static inline struct mptcp_data_frag *mptcp_rtx_head(struct sock *sk) 396 { 397 struct mptcp_sock *msk = mptcp_sk(sk); 398 399 if (msk->snd_una == READ_ONCE(msk->snd_nxt)) 400 return NULL; 401 402 return list_first_entry_or_null(&msk->rtx_queue, struct mptcp_data_frag, list); 403 } 404 405 struct csum_pseudo_header { 406 __be64 data_seq; 407 __be32 subflow_seq; 408 __be16 data_len; 409 __sum16 csum; 410 }; 411 412 struct mptcp_subflow_request_sock { 413 struct tcp_request_sock sk; 414 u16 mp_capable : 1, 415 mp_join : 1, 416 backup : 1, 417 csum_reqd : 1, 418 allow_join_id0 : 1; 419 u8 local_id; 420 u8 remote_id; 421 u64 local_key; 422 u64 idsn; 423 u32 token; 424 u32 ssn_offset; 425 u64 thmac; 426 u32 local_nonce; 427 u32 remote_nonce; 428 struct mptcp_sock *msk; 429 struct hlist_nulls_node token_node; 430 }; 431 432 static inline struct mptcp_subflow_request_sock * 433 mptcp_subflow_rsk(const struct request_sock *rsk) 434 { 435 return (struct mptcp_subflow_request_sock *)rsk; 436 } 437 438 enum mptcp_data_avail { 439 MPTCP_SUBFLOW_NODATA, 440 MPTCP_SUBFLOW_DATA_AVAIL, 441 }; 442 443 struct mptcp_delegated_action { 444 struct napi_struct napi; 445 struct list_head head; 446 }; 447 448 DECLARE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions); 449 450 #define MPTCP_DELEGATE_SEND 0 451 #define MPTCP_DELEGATE_ACK 1 452 453 /* MPTCP subflow context */ 454 struct mptcp_subflow_context { 455 struct list_head node;/* conn_list of subflows */ 456 457 struct_group(reset, 458 459 unsigned long avg_pacing_rate; /* protected by msk socket lock */ 460 u64 local_key; 461 u64 remote_key; 462 u64 idsn; 463 u64 map_seq; 464 u32 snd_isn; 465 u32 token; 466 u32 rel_write_seq; 467 u32 map_subflow_seq; 468 u32 ssn_offset; 469 u32 map_data_len; 470 __wsum map_data_csum; 471 u32 map_csum_len; 472 u32 request_mptcp : 1, /* send MP_CAPABLE */ 473 request_join : 1, /* send MP_JOIN */ 474 request_bkup : 1, 475 mp_capable : 1, /* remote is MPTCP capable */ 476 mp_join : 1, /* remote is JOINing */ 477 fully_established : 1, /* path validated */ 478 pm_notified : 1, /* PM hook called for established status */ 479 conn_finished : 1, 480 map_valid : 1, 481 map_csum_reqd : 1, 482 map_data_fin : 1, 483 mpc_map : 1, 484 backup : 1, 485 send_mp_prio : 1, 486 send_mp_fail : 1, 487 send_fastclose : 1, 488 send_infinite_map : 1, 489 remote_key_valid : 1, /* received the peer key from */ 490 disposable : 1, /* ctx can be free at ulp release time */ 491 stale : 1, /* unable to snd/rcv data, do not use for xmit */ 492 local_id_valid : 1, /* local_id is correctly initialized */ 493 valid_csum_seen : 1, /* at least one csum validated */ 494 is_mptfo : 1, /* subflow is doing TFO */ 495 __unused : 9; 496 enum mptcp_data_avail data_avail; 497 u32 remote_nonce; 498 u64 thmac; 499 u32 local_nonce; 500 u32 remote_token; 501 union { 502 u8 hmac[MPTCPOPT_HMAC_LEN]; /* MPJ subflow only */ 503 u64 iasn; /* initial ack sequence number, MPC subflows only */ 504 }; 505 u8 local_id; 506 u8 remote_id; 507 u8 reset_seen:1; 508 u8 reset_transient:1; 509 u8 reset_reason:4; 510 u8 stale_count; 511 512 u32 subflow_id; 513 514 long delegated_status; 515 unsigned long fail_tout; 516 517 ); 518 519 struct list_head delegated_node; /* link into delegated_action, protected by local BH */ 520 521 u32 setsockopt_seq; 522 u32 stale_rcv_tstamp; 523 524 struct sock *tcp_sock; /* tcp sk backpointer */ 525 struct sock *conn; /* parent mptcp_sock */ 526 const struct inet_connection_sock_af_ops *icsk_af_ops; 527 void (*tcp_state_change)(struct sock *sk); 528 void (*tcp_error_report)(struct sock *sk); 529 530 struct rcu_head rcu; 531 }; 532 533 static inline struct mptcp_subflow_context * 534 mptcp_subflow_ctx(const struct sock *sk) 535 { 536 struct inet_connection_sock *icsk = inet_csk(sk); 537 538 /* Use RCU on icsk_ulp_data only for sock diag code */ 539 return (__force struct mptcp_subflow_context *)icsk->icsk_ulp_data; 540 } 541 542 static inline struct sock * 543 mptcp_subflow_tcp_sock(const struct mptcp_subflow_context *subflow) 544 { 545 return subflow->tcp_sock; 546 } 547 548 static inline void 549 mptcp_subflow_ctx_reset(struct mptcp_subflow_context *subflow) 550 { 551 memset(&subflow->reset, 0, sizeof(subflow->reset)); 552 subflow->request_mptcp = 1; 553 } 554 555 static inline u64 556 mptcp_subflow_get_map_offset(const struct mptcp_subflow_context *subflow) 557 { 558 return tcp_sk(mptcp_subflow_tcp_sock(subflow))->copied_seq - 559 subflow->ssn_offset - 560 subflow->map_subflow_seq; 561 } 562 563 static inline u64 564 mptcp_subflow_get_mapped_dsn(const struct mptcp_subflow_context *subflow) 565 { 566 return subflow->map_seq + mptcp_subflow_get_map_offset(subflow); 567 } 568 569 void mptcp_subflow_process_delegated(struct sock *ssk); 570 571 static inline void mptcp_subflow_delegate(struct mptcp_subflow_context *subflow, int action) 572 { 573 struct mptcp_delegated_action *delegated; 574 bool schedule; 575 576 /* the caller held the subflow bh socket lock */ 577 lockdep_assert_in_softirq(); 578 579 /* The implied barrier pairs with mptcp_subflow_delegated_done(), and 580 * ensures the below list check sees list updates done prior to status 581 * bit changes 582 */ 583 if (!test_and_set_bit(action, &subflow->delegated_status)) { 584 /* still on delegated list from previous scheduling */ 585 if (!list_empty(&subflow->delegated_node)) 586 return; 587 588 delegated = this_cpu_ptr(&mptcp_delegated_actions); 589 schedule = list_empty(&delegated->head); 590 list_add_tail(&subflow->delegated_node, &delegated->head); 591 sock_hold(mptcp_subflow_tcp_sock(subflow)); 592 if (schedule) 593 napi_schedule(&delegated->napi); 594 } 595 } 596 597 static inline struct mptcp_subflow_context * 598 mptcp_subflow_delegated_next(struct mptcp_delegated_action *delegated) 599 { 600 struct mptcp_subflow_context *ret; 601 602 if (list_empty(&delegated->head)) 603 return NULL; 604 605 ret = list_first_entry(&delegated->head, struct mptcp_subflow_context, delegated_node); 606 list_del_init(&ret->delegated_node); 607 return ret; 608 } 609 610 static inline bool mptcp_subflow_has_delegated_action(const struct mptcp_subflow_context *subflow) 611 { 612 return !!READ_ONCE(subflow->delegated_status); 613 } 614 615 static inline void mptcp_subflow_delegated_done(struct mptcp_subflow_context *subflow, int action) 616 { 617 /* pairs with mptcp_subflow_delegate, ensures delegate_node is updated before 618 * touching the status bit 619 */ 620 smp_wmb(); 621 clear_bit(action, &subflow->delegated_status); 622 } 623 624 int mptcp_is_enabled(const struct net *net); 625 unsigned int mptcp_get_add_addr_timeout(const struct net *net); 626 int mptcp_is_checksum_enabled(const struct net *net); 627 int mptcp_allow_join_id0(const struct net *net); 628 unsigned int mptcp_stale_loss_cnt(const struct net *net); 629 int mptcp_get_pm_type(const struct net *net); 630 void mptcp_subflow_fully_established(struct mptcp_subflow_context *subflow, 631 const struct mptcp_options_received *mp_opt); 632 bool __mptcp_retransmit_pending_data(struct sock *sk); 633 void mptcp_check_and_set_pending(struct sock *sk); 634 void __mptcp_push_pending(struct sock *sk, unsigned int flags); 635 bool mptcp_subflow_data_available(struct sock *sk); 636 void __init mptcp_subflow_init(void); 637 void mptcp_subflow_shutdown(struct sock *sk, struct sock *ssk, int how); 638 void mptcp_close_ssk(struct sock *sk, struct sock *ssk, 639 struct mptcp_subflow_context *subflow); 640 void __mptcp_subflow_send_ack(struct sock *ssk); 641 void mptcp_subflow_reset(struct sock *ssk); 642 void mptcp_subflow_queue_clean(struct sock *sk, struct sock *ssk); 643 void mptcp_sock_graft(struct sock *sk, struct socket *parent); 644 struct socket *__mptcp_nmpc_socket(struct mptcp_sock *msk); 645 bool __mptcp_close(struct sock *sk, long timeout); 646 void mptcp_cancel_work(struct sock *sk); 647 void __mptcp_unaccepted_force_close(struct sock *sk); 648 void mptcp_set_owner_r(struct sk_buff *skb, struct sock *sk); 649 650 bool mptcp_addresses_equal(const struct mptcp_addr_info *a, 651 const struct mptcp_addr_info *b, bool use_port); 652 void mptcp_local_address(const struct sock_common *skc, struct mptcp_addr_info *addr); 653 654 /* called with sk socket lock held */ 655 int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_addr_info *loc, 656 const struct mptcp_addr_info *remote); 657 int mptcp_subflow_create_socket(struct sock *sk, unsigned short family, 658 struct socket **new_sock); 659 void mptcp_info2sockaddr(const struct mptcp_addr_info *info, 660 struct sockaddr_storage *addr, 661 unsigned short family); 662 663 static inline bool __tcp_can_send(const struct sock *ssk) 664 { 665 /* only send if our side has not closed yet */ 666 return ((1 << inet_sk_state_load(ssk)) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)); 667 } 668 669 static inline bool __mptcp_subflow_active(struct mptcp_subflow_context *subflow) 670 { 671 /* can't send if JOIN hasn't completed yet (i.e. is usable for mptcp) */ 672 if (subflow->request_join && !subflow->fully_established) 673 return false; 674 675 return __tcp_can_send(mptcp_subflow_tcp_sock(subflow)); 676 } 677 678 void mptcp_subflow_set_active(struct mptcp_subflow_context *subflow); 679 680 bool mptcp_subflow_active(struct mptcp_subflow_context *subflow); 681 682 void mptcp_subflow_drop_ctx(struct sock *ssk); 683 684 static inline void mptcp_subflow_tcp_fallback(struct sock *sk, 685 struct mptcp_subflow_context *ctx) 686 { 687 sk->sk_data_ready = sock_def_readable; 688 sk->sk_state_change = ctx->tcp_state_change; 689 sk->sk_write_space = sk_stream_write_space; 690 sk->sk_error_report = ctx->tcp_error_report; 691 692 inet_csk(sk)->icsk_af_ops = ctx->icsk_af_ops; 693 } 694 695 void __init mptcp_proto_init(void); 696 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 697 int __init mptcp_proto_v6_init(void); 698 #endif 699 700 struct sock *mptcp_sk_clone_init(const struct sock *sk, 701 const struct mptcp_options_received *mp_opt, 702 struct sock *ssk, 703 struct request_sock *req); 704 void mptcp_get_options(const struct sk_buff *skb, 705 struct mptcp_options_received *mp_opt); 706 707 void mptcp_finish_connect(struct sock *sk); 708 void __mptcp_set_connected(struct sock *sk); 709 void mptcp_reset_timeout(struct mptcp_sock *msk, unsigned long fail_tout); 710 static inline bool mptcp_is_fully_established(struct sock *sk) 711 { 712 return inet_sk_state_load(sk) == TCP_ESTABLISHED && 713 READ_ONCE(mptcp_sk(sk)->fully_established); 714 } 715 void mptcp_rcv_space_init(struct mptcp_sock *msk, const struct sock *ssk); 716 void mptcp_data_ready(struct sock *sk, struct sock *ssk); 717 bool mptcp_finish_join(struct sock *sk); 718 bool mptcp_schedule_work(struct sock *sk); 719 int mptcp_setsockopt(struct sock *sk, int level, int optname, 720 sockptr_t optval, unsigned int optlen); 721 int mptcp_getsockopt(struct sock *sk, int level, int optname, 722 char __user *optval, int __user *option); 723 724 u64 __mptcp_expand_seq(u64 old_seq, u64 cur_seq); 725 static inline u64 mptcp_expand_seq(u64 old_seq, u64 cur_seq, bool use_64bit) 726 { 727 if (use_64bit) 728 return cur_seq; 729 730 return __mptcp_expand_seq(old_seq, cur_seq); 731 } 732 void __mptcp_check_push(struct sock *sk, struct sock *ssk); 733 void __mptcp_data_acked(struct sock *sk); 734 void __mptcp_error_report(struct sock *sk); 735 bool mptcp_update_rcv_data_fin(struct mptcp_sock *msk, u64 data_fin_seq, bool use_64bit); 736 static inline bool mptcp_data_fin_enabled(const struct mptcp_sock *msk) 737 { 738 return READ_ONCE(msk->snd_data_fin_enable) && 739 READ_ONCE(msk->write_seq) == READ_ONCE(msk->snd_nxt); 740 } 741 742 static inline bool mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk) 743 { 744 if ((sk->sk_userlocks & SOCK_SNDBUF_LOCK) || ssk->sk_sndbuf <= READ_ONCE(sk->sk_sndbuf)) 745 return false; 746 747 WRITE_ONCE(sk->sk_sndbuf, ssk->sk_sndbuf); 748 return true; 749 } 750 751 static inline void mptcp_write_space(struct sock *sk) 752 { 753 if (sk_stream_is_writeable(sk)) { 754 /* pairs with memory barrier in mptcp_poll */ 755 smp_mb(); 756 if (test_and_clear_bit(MPTCP_NOSPACE, &mptcp_sk(sk)->flags)) 757 sk_stream_write_space(sk); 758 } 759 } 760 761 void mptcp_destroy_common(struct mptcp_sock *msk, unsigned int flags); 762 763 #define MPTCP_TOKEN_MAX_RETRIES 4 764 765 void __init mptcp_token_init(void); 766 static inline void mptcp_token_init_request(struct request_sock *req) 767 { 768 mptcp_subflow_rsk(req)->token_node.pprev = NULL; 769 } 770 771 int mptcp_token_new_request(struct request_sock *req); 772 void mptcp_token_destroy_request(struct request_sock *req); 773 int mptcp_token_new_connect(struct sock *ssk); 774 void mptcp_token_accept(struct mptcp_subflow_request_sock *r, 775 struct mptcp_sock *msk); 776 bool mptcp_token_exists(u32 token); 777 struct mptcp_sock *mptcp_token_get_sock(struct net *net, u32 token); 778 struct mptcp_sock *mptcp_token_iter_next(const struct net *net, long *s_slot, 779 long *s_num); 780 void mptcp_token_destroy(struct mptcp_sock *msk); 781 782 void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn); 783 784 void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u8 *msg, int len, void *hmac); 785 __sum16 __mptcp_make_csum(u64 data_seq, u32 subflow_seq, u16 data_len, __wsum sum); 786 787 void __init mptcp_pm_init(void); 788 void mptcp_pm_data_init(struct mptcp_sock *msk); 789 void mptcp_pm_data_reset(struct mptcp_sock *msk); 790 int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info, 791 struct mptcp_addr_info *addr); 792 int mptcp_pm_parse_entry(struct nlattr *attr, struct genl_info *info, 793 bool require_family, 794 struct mptcp_pm_addr_entry *entry); 795 bool mptcp_pm_addr_families_match(const struct sock *sk, 796 const struct mptcp_addr_info *loc, 797 const struct mptcp_addr_info *rem); 798 void mptcp_pm_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); 799 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); 800 void mptcp_pm_new_connection(struct mptcp_sock *msk, const struct sock *ssk, int server_side); 801 void mptcp_pm_fully_established(struct mptcp_sock *msk, const struct sock *ssk); 802 bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk); 803 void mptcp_pm_connection_closed(struct mptcp_sock *msk); 804 void mptcp_pm_subflow_established(struct mptcp_sock *msk); 805 bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk); 806 void mptcp_pm_subflow_check_next(struct mptcp_sock *msk, const struct sock *ssk, 807 const struct mptcp_subflow_context *subflow); 808 void mptcp_pm_add_addr_received(const struct sock *ssk, 809 const struct mptcp_addr_info *addr); 810 void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk, 811 const struct mptcp_addr_info *addr); 812 void mptcp_pm_add_addr_send_ack(struct mptcp_sock *msk); 813 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk); 814 void mptcp_pm_rm_addr_received(struct mptcp_sock *msk, 815 const struct mptcp_rm_list *rm_list); 816 void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup); 817 void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq); 818 int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk, 819 struct mptcp_addr_info *addr, 820 struct mptcp_addr_info *rem, 821 u8 bkup); 822 bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk, 823 const struct mptcp_addr_info *addr); 824 void mptcp_pm_free_anno_list(struct mptcp_sock *msk); 825 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk); 826 struct mptcp_pm_add_entry * 827 mptcp_pm_del_add_timer(struct mptcp_sock *msk, 828 const struct mptcp_addr_info *addr, bool check_id); 829 struct mptcp_pm_add_entry * 830 mptcp_lookup_anno_list_by_saddr(const struct mptcp_sock *msk, 831 const struct mptcp_addr_info *addr); 832 int mptcp_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, 833 unsigned int id, 834 u8 *flags, int *ifindex); 835 int mptcp_pm_nl_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, unsigned int id, 836 u8 *flags, int *ifindex); 837 int mptcp_userspace_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, 838 unsigned int id, 839 u8 *flags, int *ifindex); 840 int mptcp_pm_set_flags(struct net *net, struct nlattr *token, 841 struct mptcp_pm_addr_entry *loc, 842 struct mptcp_pm_addr_entry *rem, u8 bkup); 843 int mptcp_pm_nl_set_flags(struct net *net, struct mptcp_pm_addr_entry *addr, u8 bkup); 844 int mptcp_userspace_pm_set_flags(struct net *net, struct nlattr *token, 845 struct mptcp_pm_addr_entry *loc, 846 struct mptcp_pm_addr_entry *rem, u8 bkup); 847 int mptcp_pm_announce_addr(struct mptcp_sock *msk, 848 const struct mptcp_addr_info *addr, 849 bool echo); 850 int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); 851 int mptcp_pm_remove_subflow(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); 852 void mptcp_pm_remove_addrs(struct mptcp_sock *msk, struct list_head *rm_list); 853 void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk, 854 struct list_head *rm_list); 855 856 void mptcp_free_local_addr_list(struct mptcp_sock *msk); 857 int mptcp_nl_cmd_announce(struct sk_buff *skb, struct genl_info *info); 858 int mptcp_nl_cmd_remove(struct sk_buff *skb, struct genl_info *info); 859 int mptcp_nl_cmd_sf_create(struct sk_buff *skb, struct genl_info *info); 860 int mptcp_nl_cmd_sf_destroy(struct sk_buff *skb, struct genl_info *info); 861 862 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk, 863 const struct sock *ssk, gfp_t gfp); 864 void mptcp_event_addr_announced(const struct sock *ssk, const struct mptcp_addr_info *info); 865 void mptcp_event_addr_removed(const struct mptcp_sock *msk, u8 id); 866 void mptcp_event_pm_listener(const struct sock *ssk, 867 enum mptcp_event_type event); 868 bool mptcp_userspace_pm_active(const struct mptcp_sock *msk); 869 870 void mptcp_fastopen_gen_msk_ackseq(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow, 871 const struct mptcp_options_received *mp_opt); 872 void mptcp_fastopen_subflow_synack_set_params(struct mptcp_subflow_context *subflow, 873 struct request_sock *req); 874 875 static inline bool mptcp_pm_should_add_signal(struct mptcp_sock *msk) 876 { 877 return READ_ONCE(msk->pm.addr_signal) & 878 (BIT(MPTCP_ADD_ADDR_SIGNAL) | BIT(MPTCP_ADD_ADDR_ECHO)); 879 } 880 881 static inline bool mptcp_pm_should_add_signal_addr(struct mptcp_sock *msk) 882 { 883 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_SIGNAL); 884 } 885 886 static inline bool mptcp_pm_should_add_signal_echo(struct mptcp_sock *msk) 887 { 888 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_ECHO); 889 } 890 891 static inline bool mptcp_pm_should_rm_signal(struct mptcp_sock *msk) 892 { 893 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_RM_ADDR_SIGNAL); 894 } 895 896 static inline bool mptcp_pm_is_userspace(const struct mptcp_sock *msk) 897 { 898 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_USERSPACE; 899 } 900 901 static inline bool mptcp_pm_is_kernel(const struct mptcp_sock *msk) 902 { 903 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_KERNEL; 904 } 905 906 static inline unsigned int mptcp_add_addr_len(int family, bool echo, bool port) 907 { 908 u8 len = TCPOLEN_MPTCP_ADD_ADDR_BASE; 909 910 if (family == AF_INET6) 911 len = TCPOLEN_MPTCP_ADD_ADDR6_BASE; 912 if (!echo) 913 len += MPTCPOPT_THMAC_LEN; 914 /* account for 2 trailing 'nop' options */ 915 if (port) 916 len += TCPOLEN_MPTCP_PORT_LEN + TCPOLEN_MPTCP_PORT_ALIGN; 917 918 return len; 919 } 920 921 static inline int mptcp_rm_addr_len(const struct mptcp_rm_list *rm_list) 922 { 923 if (rm_list->nr == 0 || rm_list->nr > MPTCP_RM_IDS_MAX) 924 return -EINVAL; 925 926 return TCPOLEN_MPTCP_RM_ADDR_BASE + roundup(rm_list->nr - 1, 4) + 1; 927 } 928 929 bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, const struct sk_buff *skb, 930 unsigned int opt_size, unsigned int remaining, 931 struct mptcp_addr_info *addr, bool *echo, 932 bool *drop_other_suboptions); 933 bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining, 934 struct mptcp_rm_list *rm_list); 935 int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc); 936 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc); 937 int mptcp_userspace_pm_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc); 938 939 void __init mptcp_pm_nl_init(void); 940 void mptcp_pm_nl_work(struct mptcp_sock *msk); 941 void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk, 942 const struct mptcp_rm_list *rm_list); 943 unsigned int mptcp_pm_get_add_addr_signal_max(const struct mptcp_sock *msk); 944 unsigned int mptcp_pm_get_add_addr_accept_max(const struct mptcp_sock *msk); 945 unsigned int mptcp_pm_get_subflows_max(const struct mptcp_sock *msk); 946 unsigned int mptcp_pm_get_local_addr_max(const struct mptcp_sock *msk); 947 948 /* called under PM lock */ 949 static inline void __mptcp_pm_close_subflow(struct mptcp_sock *msk) 950 { 951 if (--msk->pm.subflows < mptcp_pm_get_subflows_max(msk)) 952 WRITE_ONCE(msk->pm.accept_subflow, true); 953 } 954 955 static inline void mptcp_pm_close_subflow(struct mptcp_sock *msk) 956 { 957 spin_lock_bh(&msk->pm.lock); 958 __mptcp_pm_close_subflow(msk); 959 spin_unlock_bh(&msk->pm.lock); 960 } 961 962 void mptcp_sockopt_sync(struct mptcp_sock *msk, struct sock *ssk); 963 void mptcp_sockopt_sync_locked(struct mptcp_sock *msk, struct sock *ssk); 964 965 static inline struct mptcp_ext *mptcp_get_ext(const struct sk_buff *skb) 966 { 967 return (struct mptcp_ext *)skb_ext_find(skb, SKB_EXT_MPTCP); 968 } 969 970 void mptcp_diag_subflow_init(struct tcp_ulp_ops *ops); 971 972 static inline bool __mptcp_check_fallback(const struct mptcp_sock *msk) 973 { 974 return test_bit(MPTCP_FALLBACK_DONE, &msk->flags); 975 } 976 977 static inline bool mptcp_check_fallback(const struct sock *sk) 978 { 979 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 980 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 981 982 return __mptcp_check_fallback(msk); 983 } 984 985 static inline void __mptcp_do_fallback(struct mptcp_sock *msk) 986 { 987 if (test_bit(MPTCP_FALLBACK_DONE, &msk->flags)) { 988 pr_debug("TCP fallback already done (msk=%p)", msk); 989 return; 990 } 991 set_bit(MPTCP_FALLBACK_DONE, &msk->flags); 992 } 993 994 static inline void mptcp_do_fallback(struct sock *ssk) 995 { 996 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 997 struct sock *sk = subflow->conn; 998 struct mptcp_sock *msk; 999 1000 msk = mptcp_sk(sk); 1001 __mptcp_do_fallback(msk); 1002 if (READ_ONCE(msk->snd_data_fin_enable) && !(ssk->sk_shutdown & SEND_SHUTDOWN)) { 1003 gfp_t saved_allocation = ssk->sk_allocation; 1004 1005 /* we are in a atomic (BH) scope, override ssk default for data 1006 * fin allocation 1007 */ 1008 ssk->sk_allocation = GFP_ATOMIC; 1009 ssk->sk_shutdown |= SEND_SHUTDOWN; 1010 tcp_shutdown(ssk, SEND_SHUTDOWN); 1011 ssk->sk_allocation = saved_allocation; 1012 } 1013 } 1014 1015 #define pr_fallback(a) pr_debug("%s:fallback to TCP (msk=%p)", __func__, a) 1016 1017 static inline bool mptcp_check_infinite_map(struct sk_buff *skb) 1018 { 1019 struct mptcp_ext *mpext; 1020 1021 mpext = skb ? mptcp_get_ext(skb) : NULL; 1022 if (mpext && mpext->infinite_map) 1023 return true; 1024 1025 return false; 1026 } 1027 1028 static inline bool is_active_ssk(struct mptcp_subflow_context *subflow) 1029 { 1030 return (subflow->request_mptcp || subflow->request_join); 1031 } 1032 1033 static inline bool subflow_simultaneous_connect(struct sock *sk) 1034 { 1035 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 1036 1037 return sk->sk_state == TCP_ESTABLISHED && 1038 is_active_ssk(subflow) && 1039 !subflow->conn_finished; 1040 } 1041 1042 #ifdef CONFIG_SYN_COOKIES 1043 void subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 1044 struct sk_buff *skb); 1045 bool mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 1046 struct sk_buff *skb); 1047 void __init mptcp_join_cookie_init(void); 1048 #else 1049 static inline void 1050 subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 1051 struct sk_buff *skb) {} 1052 static inline bool 1053 mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 1054 struct sk_buff *skb) 1055 { 1056 return false; 1057 } 1058 1059 static inline void mptcp_join_cookie_init(void) {} 1060 #endif 1061 1062 #endif /* __MPTCP_PROTOCOL_H */ 1063