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_SYNC_STATE 6 126 #define MPTCP_SYNC_SNDBUF 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 u64 bytes_consumed; 272 int rmem_fwd_alloc; 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 bool recovery; /* closing subflow write queue reinjected */ 288 bool can_ack; 289 bool fully_established; 290 bool rcv_data_fin; 291 bool snd_data_fin_enable; 292 bool rcv_fastclose; 293 bool use_64bit_ack; /* Set when we received a 64-bit DSN */ 294 bool csum_enabled; 295 bool allow_infinite_fallback; 296 u8 pending_state; /* A subflow asked to set this sk_state, 297 * protected by the msk data lock 298 */ 299 u8 mpc_endpoint_id; 300 u8 recvmsg_inq:1, 301 cork:1, 302 nodelay:1, 303 fastopening:1, 304 in_accept_queue:1, 305 free_first:1, 306 rcvspace_init:1; 307 int keepalive_cnt; 308 int keepalive_idle; 309 int keepalive_intvl; 310 struct work_struct work; 311 struct sk_buff *ooo_last_skb; 312 struct rb_root out_of_order_queue; 313 struct sk_buff_head receive_queue; 314 struct list_head conn_list; 315 struct list_head rtx_queue; 316 struct mptcp_data_frag *first_pending; 317 struct list_head join_list; 318 struct sock *first; /* The mptcp ops can safely dereference, using suitable 319 * ONCE annotation, the subflow outside the socket 320 * lock as such sock is freed after close(). 321 */ 322 struct mptcp_pm_data pm; 323 struct mptcp_sched_ops *sched; 324 struct { 325 u32 space; /* bytes copied in last measurement window */ 326 u32 copied; /* bytes copied in this measurement window */ 327 u64 time; /* start time of measurement window */ 328 u64 rtt_us; /* last maximum rtt of subflows */ 329 } rcvq_space; 330 u8 scaling_ratio; 331 332 u32 subflow_id; 333 u32 setsockopt_seq; 334 char ca_name[TCP_CA_NAME_MAX]; 335 }; 336 337 #define mptcp_data_lock(sk) spin_lock_bh(&(sk)->sk_lock.slock) 338 #define mptcp_data_unlock(sk) spin_unlock_bh(&(sk)->sk_lock.slock) 339 340 #define mptcp_for_each_subflow(__msk, __subflow) \ 341 list_for_each_entry(__subflow, &((__msk)->conn_list), node) 342 #define mptcp_for_each_subflow_safe(__msk, __subflow, __tmp) \ 343 list_for_each_entry_safe(__subflow, __tmp, &((__msk)->conn_list), node) 344 345 static inline void msk_owned_by_me(const struct mptcp_sock *msk) 346 { 347 sock_owned_by_me((const struct sock *)msk); 348 } 349 350 #define mptcp_sk(ptr) container_of_const(ptr, struct mptcp_sock, sk.icsk_inet.sk) 351 352 /* the msk socket don't use the backlog, also account for the bulk 353 * free memory 354 */ 355 static inline int __mptcp_rmem(const struct sock *sk) 356 { 357 return atomic_read(&sk->sk_rmem_alloc) - READ_ONCE(mptcp_sk(sk)->rmem_released); 358 } 359 360 static inline int mptcp_win_from_space(const struct sock *sk, int space) 361 { 362 return __tcp_win_from_space(mptcp_sk(sk)->scaling_ratio, space); 363 } 364 365 static inline int __mptcp_space(const struct sock *sk) 366 { 367 return mptcp_win_from_space(sk, READ_ONCE(sk->sk_rcvbuf) - __mptcp_rmem(sk)); 368 } 369 370 static inline struct mptcp_data_frag *mptcp_send_head(const struct sock *sk) 371 { 372 const struct mptcp_sock *msk = mptcp_sk(sk); 373 374 return READ_ONCE(msk->first_pending); 375 } 376 377 static inline struct mptcp_data_frag *mptcp_send_next(struct sock *sk) 378 { 379 struct mptcp_sock *msk = mptcp_sk(sk); 380 struct mptcp_data_frag *cur; 381 382 cur = msk->first_pending; 383 return list_is_last(&cur->list, &msk->rtx_queue) ? NULL : 384 list_next_entry(cur, list); 385 } 386 387 static inline struct mptcp_data_frag *mptcp_pending_tail(const struct sock *sk) 388 { 389 const struct mptcp_sock *msk = mptcp_sk(sk); 390 391 if (!msk->first_pending) 392 return NULL; 393 394 if (WARN_ON_ONCE(list_empty(&msk->rtx_queue))) 395 return NULL; 396 397 return list_last_entry(&msk->rtx_queue, struct mptcp_data_frag, list); 398 } 399 400 static inline struct mptcp_data_frag *mptcp_rtx_head(struct sock *sk) 401 { 402 struct mptcp_sock *msk = mptcp_sk(sk); 403 404 if (msk->snd_una == READ_ONCE(msk->snd_nxt)) 405 return NULL; 406 407 return list_first_entry_or_null(&msk->rtx_queue, struct mptcp_data_frag, list); 408 } 409 410 struct csum_pseudo_header { 411 __be64 data_seq; 412 __be32 subflow_seq; 413 __be16 data_len; 414 __sum16 csum; 415 }; 416 417 struct mptcp_subflow_request_sock { 418 struct tcp_request_sock sk; 419 u16 mp_capable : 1, 420 mp_join : 1, 421 backup : 1, 422 request_bkup : 1, 423 csum_reqd : 1, 424 allow_join_id0 : 1; 425 u8 local_id; 426 u8 remote_id; 427 u64 local_key; 428 u64 idsn; 429 u32 token; 430 u32 ssn_offset; 431 u64 thmac; 432 u32 local_nonce; 433 u32 remote_nonce; 434 struct mptcp_sock *msk; 435 struct hlist_nulls_node token_node; 436 }; 437 438 static inline struct mptcp_subflow_request_sock * 439 mptcp_subflow_rsk(const struct request_sock *rsk) 440 { 441 return (struct mptcp_subflow_request_sock *)rsk; 442 } 443 444 enum mptcp_data_avail { 445 MPTCP_SUBFLOW_NODATA, 446 MPTCP_SUBFLOW_DATA_AVAIL, 447 }; 448 449 struct mptcp_delegated_action { 450 struct napi_struct napi; 451 struct list_head head; 452 }; 453 454 DECLARE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions); 455 456 #define MPTCP_DELEGATE_SCHEDULED 0 457 #define MPTCP_DELEGATE_SEND 1 458 #define MPTCP_DELEGATE_ACK 2 459 #define MPTCP_DELEGATE_SNDBUF 3 460 461 #define MPTCP_DELEGATE_ACTIONS_MASK (~BIT(MPTCP_DELEGATE_SCHEDULED)) 462 /* MPTCP subflow context */ 463 struct mptcp_subflow_context { 464 struct list_head node;/* conn_list of subflows */ 465 466 struct_group(reset, 467 468 unsigned long avg_pacing_rate; /* protected by msk socket lock */ 469 u64 local_key; 470 u64 remote_key; 471 u64 idsn; 472 u64 map_seq; 473 u32 snd_isn; 474 u32 token; 475 u32 rel_write_seq; 476 u32 map_subflow_seq; 477 u32 ssn_offset; 478 u32 map_data_len; 479 __wsum map_data_csum; 480 u32 map_csum_len; 481 u32 request_mptcp : 1, /* send MP_CAPABLE */ 482 request_join : 1, /* send MP_JOIN */ 483 request_bkup : 1, 484 mp_capable : 1, /* remote is MPTCP capable */ 485 mp_join : 1, /* remote is JOINing */ 486 fully_established : 1, /* path validated */ 487 pm_notified : 1, /* PM hook called for established status */ 488 conn_finished : 1, 489 map_valid : 1, 490 map_csum_reqd : 1, 491 map_data_fin : 1, 492 mpc_map : 1, 493 backup : 1, 494 send_mp_prio : 1, 495 send_mp_fail : 1, 496 send_fastclose : 1, 497 send_infinite_map : 1, 498 remote_key_valid : 1, /* received the peer key from */ 499 disposable : 1, /* ctx can be free at ulp release time */ 500 stale : 1, /* unable to snd/rcv data, do not use for xmit */ 501 valid_csum_seen : 1, /* at least one csum validated */ 502 is_mptfo : 1, /* subflow is doing TFO */ 503 close_event_done : 1, /* has done the post-closed part */ 504 __unused : 9; 505 enum mptcp_data_avail data_avail; 506 bool scheduled; 507 u32 remote_nonce; 508 u64 thmac; 509 u32 local_nonce; 510 u32 remote_token; 511 union { 512 u8 hmac[MPTCPOPT_HMAC_LEN]; /* MPJ subflow only */ 513 u64 iasn; /* initial ack sequence number, MPC subflows only */ 514 }; 515 s16 local_id; /* if negative not initialized yet */ 516 u8 remote_id; 517 u8 reset_seen:1; 518 u8 reset_transient:1; 519 u8 reset_reason:4; 520 u8 stale_count; 521 522 u32 subflow_id; 523 524 long delegated_status; 525 unsigned long fail_tout; 526 527 ); 528 529 struct list_head delegated_node; /* link into delegated_action, protected by local BH */ 530 531 u32 setsockopt_seq; 532 u32 stale_rcv_tstamp; 533 int cached_sndbuf; /* sndbuf size when last synced with the msk sndbuf, 534 * protected by the msk socket lock 535 */ 536 537 struct sock *tcp_sock; /* tcp sk backpointer */ 538 struct sock *conn; /* parent mptcp_sock */ 539 const struct inet_connection_sock_af_ops *icsk_af_ops; 540 void (*tcp_state_change)(struct sock *sk); 541 void (*tcp_error_report)(struct sock *sk); 542 543 struct rcu_head rcu; 544 }; 545 546 static inline struct mptcp_subflow_context * 547 mptcp_subflow_ctx(const struct sock *sk) 548 { 549 struct inet_connection_sock *icsk = inet_csk(sk); 550 551 /* Use RCU on icsk_ulp_data only for sock diag code */ 552 return (__force struct mptcp_subflow_context *)icsk->icsk_ulp_data; 553 } 554 555 static inline struct sock * 556 mptcp_subflow_tcp_sock(const struct mptcp_subflow_context *subflow) 557 { 558 return subflow->tcp_sock; 559 } 560 561 static inline void 562 mptcp_subflow_ctx_reset(struct mptcp_subflow_context *subflow) 563 { 564 memset(&subflow->reset, 0, sizeof(subflow->reset)); 565 subflow->request_mptcp = 1; 566 WRITE_ONCE(subflow->local_id, -1); 567 } 568 569 static inline u64 570 mptcp_subflow_get_map_offset(const struct mptcp_subflow_context *subflow) 571 { 572 return tcp_sk(mptcp_subflow_tcp_sock(subflow))->copied_seq - 573 subflow->ssn_offset - 574 subflow->map_subflow_seq; 575 } 576 577 static inline u64 578 mptcp_subflow_get_mapped_dsn(const struct mptcp_subflow_context *subflow) 579 { 580 return subflow->map_seq + mptcp_subflow_get_map_offset(subflow); 581 } 582 583 void mptcp_subflow_process_delegated(struct sock *ssk, long actions); 584 585 static inline void mptcp_subflow_delegate(struct mptcp_subflow_context *subflow, int action) 586 { 587 long old, set_bits = BIT(MPTCP_DELEGATE_SCHEDULED) | BIT(action); 588 struct mptcp_delegated_action *delegated; 589 bool schedule; 590 591 /* the caller held the subflow bh socket lock */ 592 lockdep_assert_in_softirq(); 593 594 /* The implied barrier pairs with tcp_release_cb_override() 595 * mptcp_napi_poll(), and ensures the below list check sees list 596 * updates done prior to delegated status bits changes 597 */ 598 old = set_mask_bits(&subflow->delegated_status, 0, set_bits); 599 if (!(old & BIT(MPTCP_DELEGATE_SCHEDULED))) { 600 if (WARN_ON_ONCE(!list_empty(&subflow->delegated_node))) 601 return; 602 603 delegated = this_cpu_ptr(&mptcp_delegated_actions); 604 schedule = list_empty(&delegated->head); 605 list_add_tail(&subflow->delegated_node, &delegated->head); 606 sock_hold(mptcp_subflow_tcp_sock(subflow)); 607 if (schedule) 608 napi_schedule(&delegated->napi); 609 } 610 } 611 612 static inline struct mptcp_subflow_context * 613 mptcp_subflow_delegated_next(struct mptcp_delegated_action *delegated) 614 { 615 struct mptcp_subflow_context *ret; 616 617 if (list_empty(&delegated->head)) 618 return NULL; 619 620 ret = list_first_entry(&delegated->head, struct mptcp_subflow_context, delegated_node); 621 list_del_init(&ret->delegated_node); 622 return ret; 623 } 624 625 int mptcp_is_enabled(const struct net *net); 626 unsigned int mptcp_get_add_addr_timeout(const struct net *net); 627 int mptcp_is_checksum_enabled(const struct net *net); 628 int mptcp_allow_join_id0(const struct net *net); 629 unsigned int mptcp_stale_loss_cnt(const struct net *net); 630 int mptcp_get_pm_type(const struct net *net); 631 const char *mptcp_get_scheduler(const struct net *net); 632 void __mptcp_subflow_fully_established(struct mptcp_sock *msk, 633 struct mptcp_subflow_context *subflow, 634 const struct mptcp_options_received *mp_opt); 635 bool __mptcp_retransmit_pending_data(struct sock *sk); 636 void mptcp_check_and_set_pending(struct sock *sk); 637 void __mptcp_push_pending(struct sock *sk, unsigned int flags); 638 bool mptcp_subflow_data_available(struct sock *sk); 639 void __init mptcp_subflow_init(void); 640 void mptcp_subflow_shutdown(struct sock *sk, struct sock *ssk, int how); 641 void mptcp_close_ssk(struct sock *sk, struct sock *ssk, 642 struct mptcp_subflow_context *subflow); 643 void __mptcp_subflow_send_ack(struct sock *ssk); 644 void mptcp_subflow_reset(struct sock *ssk); 645 void mptcp_subflow_queue_clean(struct sock *sk, struct sock *ssk); 646 void mptcp_sock_graft(struct sock *sk, struct socket *parent); 647 struct sock *__mptcp_nmpc_sk(struct mptcp_sock *msk); 648 bool __mptcp_close(struct sock *sk, long timeout); 649 void mptcp_cancel_work(struct sock *sk); 650 void __mptcp_unaccepted_force_close(struct sock *sk); 651 void mptcp_set_owner_r(struct sk_buff *skb, struct sock *sk); 652 void mptcp_set_state(struct sock *sk, int state); 653 654 bool mptcp_addresses_equal(const struct mptcp_addr_info *a, 655 const struct mptcp_addr_info *b, bool use_port); 656 void mptcp_local_address(const struct sock_common *skc, struct mptcp_addr_info *addr); 657 658 /* called with sk socket lock held */ 659 int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_addr_info *loc, 660 const struct mptcp_addr_info *remote); 661 int mptcp_subflow_create_socket(struct sock *sk, unsigned short family, 662 struct socket **new_sock); 663 void mptcp_info2sockaddr(const struct mptcp_addr_info *info, 664 struct sockaddr_storage *addr, 665 unsigned short family); 666 struct mptcp_sched_ops *mptcp_sched_find(const char *name); 667 int mptcp_register_scheduler(struct mptcp_sched_ops *sched); 668 void mptcp_unregister_scheduler(struct mptcp_sched_ops *sched); 669 void mptcp_sched_init(void); 670 int mptcp_init_sched(struct mptcp_sock *msk, 671 struct mptcp_sched_ops *sched); 672 void mptcp_release_sched(struct mptcp_sock *msk); 673 void mptcp_subflow_set_scheduled(struct mptcp_subflow_context *subflow, 674 bool scheduled); 675 struct sock *mptcp_subflow_get_send(struct mptcp_sock *msk); 676 struct sock *mptcp_subflow_get_retrans(struct mptcp_sock *msk); 677 int mptcp_sched_get_send(struct mptcp_sock *msk); 678 int mptcp_sched_get_retrans(struct mptcp_sock *msk); 679 680 static inline u64 mptcp_data_avail(const struct mptcp_sock *msk) 681 { 682 return READ_ONCE(msk->bytes_received) - READ_ONCE(msk->bytes_consumed); 683 } 684 685 static inline bool mptcp_epollin_ready(const struct sock *sk) 686 { 687 /* mptcp doesn't have to deal with small skbs in the receive queue, 688 * at it can always coalesce them 689 */ 690 return (mptcp_data_avail(mptcp_sk(sk)) >= sk->sk_rcvlowat) || 691 (mem_cgroup_sockets_enabled && sk->sk_memcg && 692 mem_cgroup_under_socket_pressure(sk->sk_memcg)) || 693 READ_ONCE(tcp_memory_pressure); 694 } 695 696 int mptcp_set_rcvlowat(struct sock *sk, int val); 697 698 static inline bool __tcp_can_send(const struct sock *ssk) 699 { 700 /* only send if our side has not closed yet */ 701 return ((1 << inet_sk_state_load(ssk)) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)); 702 } 703 704 static inline bool __mptcp_subflow_active(struct mptcp_subflow_context *subflow) 705 { 706 /* can't send if JOIN hasn't completed yet (i.e. is usable for mptcp) */ 707 if (subflow->request_join && !subflow->fully_established) 708 return false; 709 710 return __tcp_can_send(mptcp_subflow_tcp_sock(subflow)); 711 } 712 713 void mptcp_subflow_set_active(struct mptcp_subflow_context *subflow); 714 715 bool mptcp_subflow_active(struct mptcp_subflow_context *subflow); 716 717 void mptcp_subflow_drop_ctx(struct sock *ssk); 718 719 static inline void mptcp_subflow_tcp_fallback(struct sock *sk, 720 struct mptcp_subflow_context *ctx) 721 { 722 sk->sk_data_ready = sock_def_readable; 723 sk->sk_state_change = ctx->tcp_state_change; 724 sk->sk_write_space = sk_stream_write_space; 725 sk->sk_error_report = ctx->tcp_error_report; 726 727 inet_csk(sk)->icsk_af_ops = ctx->icsk_af_ops; 728 } 729 730 void __init mptcp_proto_init(void); 731 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 732 int __init mptcp_proto_v6_init(void); 733 #endif 734 735 struct sock *mptcp_sk_clone_init(const struct sock *sk, 736 const struct mptcp_options_received *mp_opt, 737 struct sock *ssk, 738 struct request_sock *req); 739 void mptcp_get_options(const struct sk_buff *skb, 740 struct mptcp_options_received *mp_opt); 741 742 void mptcp_finish_connect(struct sock *sk); 743 void __mptcp_sync_state(struct sock *sk, int state); 744 void mptcp_reset_tout_timer(struct mptcp_sock *msk, unsigned long fail_tout); 745 746 static inline void mptcp_stop_tout_timer(struct sock *sk) 747 { 748 if (!inet_csk(sk)->icsk_mtup.probe_timestamp) 749 return; 750 751 sk_stop_timer(sk, &sk->sk_timer); 752 inet_csk(sk)->icsk_mtup.probe_timestamp = 0; 753 } 754 755 static inline void mptcp_set_close_tout(struct sock *sk, unsigned long tout) 756 { 757 /* avoid 0 timestamp, as that means no close timeout */ 758 inet_csk(sk)->icsk_mtup.probe_timestamp = tout ? : 1; 759 } 760 761 static inline void mptcp_start_tout_timer(struct sock *sk) 762 { 763 mptcp_set_close_tout(sk, tcp_jiffies32); 764 mptcp_reset_tout_timer(mptcp_sk(sk), 0); 765 } 766 767 static inline bool mptcp_is_fully_established(struct sock *sk) 768 { 769 return inet_sk_state_load(sk) == TCP_ESTABLISHED && 770 READ_ONCE(mptcp_sk(sk)->fully_established); 771 } 772 773 void mptcp_rcv_space_init(struct mptcp_sock *msk, const struct sock *ssk); 774 void mptcp_data_ready(struct sock *sk, struct sock *ssk); 775 bool mptcp_finish_join(struct sock *sk); 776 bool mptcp_schedule_work(struct sock *sk); 777 int mptcp_setsockopt(struct sock *sk, int level, int optname, 778 sockptr_t optval, unsigned int optlen); 779 int mptcp_getsockopt(struct sock *sk, int level, int optname, 780 char __user *optval, int __user *option); 781 782 u64 __mptcp_expand_seq(u64 old_seq, u64 cur_seq); 783 static inline u64 mptcp_expand_seq(u64 old_seq, u64 cur_seq, bool use_64bit) 784 { 785 if (use_64bit) 786 return cur_seq; 787 788 return __mptcp_expand_seq(old_seq, cur_seq); 789 } 790 void __mptcp_check_push(struct sock *sk, struct sock *ssk); 791 void __mptcp_data_acked(struct sock *sk); 792 void __mptcp_error_report(struct sock *sk); 793 bool mptcp_update_rcv_data_fin(struct mptcp_sock *msk, u64 data_fin_seq, bool use_64bit); 794 static inline bool mptcp_data_fin_enabled(const struct mptcp_sock *msk) 795 { 796 return READ_ONCE(msk->snd_data_fin_enable) && 797 READ_ONCE(msk->write_seq) == READ_ONCE(msk->snd_nxt); 798 } 799 800 static inline void mptcp_write_space(struct sock *sk) 801 { 802 if (sk_stream_is_writeable(sk)) { 803 /* pairs with memory barrier in mptcp_poll */ 804 smp_mb(); 805 if (test_and_clear_bit(MPTCP_NOSPACE, &mptcp_sk(sk)->flags)) 806 sk_stream_write_space(sk); 807 } 808 } 809 810 static inline void __mptcp_sync_sndbuf(struct sock *sk) 811 { 812 struct mptcp_subflow_context *subflow; 813 int ssk_sndbuf, new_sndbuf; 814 815 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) 816 return; 817 818 new_sndbuf = sock_net(sk)->ipv4.sysctl_tcp_wmem[0]; 819 mptcp_for_each_subflow(mptcp_sk(sk), subflow) { 820 ssk_sndbuf = READ_ONCE(mptcp_subflow_tcp_sock(subflow)->sk_sndbuf); 821 822 subflow->cached_sndbuf = ssk_sndbuf; 823 new_sndbuf += ssk_sndbuf; 824 } 825 826 /* the msk max wmem limit is <nr_subflows> * tcp wmem[2] */ 827 WRITE_ONCE(sk->sk_sndbuf, new_sndbuf); 828 mptcp_write_space(sk); 829 } 830 831 /* The called held both the msk socket and the subflow socket locks, 832 * possibly under BH 833 */ 834 static inline void __mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk) 835 { 836 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 837 838 if (READ_ONCE(ssk->sk_sndbuf) != subflow->cached_sndbuf) 839 __mptcp_sync_sndbuf(sk); 840 } 841 842 /* the caller held only the subflow socket lock, either in process or 843 * BH context. Additionally this can be called under the msk data lock, 844 * so we can't acquire such lock here: let the delegate action acquires 845 * the needed locks in suitable order. 846 */ 847 static inline void mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk) 848 { 849 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 850 851 if (likely(READ_ONCE(ssk->sk_sndbuf) == subflow->cached_sndbuf)) 852 return; 853 854 local_bh_disable(); 855 mptcp_subflow_delegate(subflow, MPTCP_DELEGATE_SNDBUF); 856 local_bh_enable(); 857 } 858 859 void mptcp_destroy_common(struct mptcp_sock *msk, unsigned int flags); 860 861 #define MPTCP_TOKEN_MAX_RETRIES 4 862 863 void __init mptcp_token_init(void); 864 static inline void mptcp_token_init_request(struct request_sock *req) 865 { 866 mptcp_subflow_rsk(req)->token_node.pprev = NULL; 867 } 868 869 int mptcp_token_new_request(struct request_sock *req); 870 void mptcp_token_destroy_request(struct request_sock *req); 871 int mptcp_token_new_connect(struct sock *ssk); 872 void mptcp_token_accept(struct mptcp_subflow_request_sock *r, 873 struct mptcp_sock *msk); 874 bool mptcp_token_exists(u32 token); 875 struct mptcp_sock *mptcp_token_get_sock(struct net *net, u32 token); 876 struct mptcp_sock *mptcp_token_iter_next(const struct net *net, long *s_slot, 877 long *s_num); 878 void mptcp_token_destroy(struct mptcp_sock *msk); 879 880 void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn); 881 882 void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u8 *msg, int len, void *hmac); 883 __sum16 __mptcp_make_csum(u64 data_seq, u32 subflow_seq, u16 data_len, __wsum sum); 884 885 void __init mptcp_pm_init(void); 886 void mptcp_pm_data_init(struct mptcp_sock *msk); 887 void mptcp_pm_data_reset(struct mptcp_sock *msk); 888 int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info, 889 struct mptcp_addr_info *addr); 890 int mptcp_pm_parse_entry(struct nlattr *attr, struct genl_info *info, 891 bool require_family, 892 struct mptcp_pm_addr_entry *entry); 893 bool mptcp_pm_addr_families_match(const struct sock *sk, 894 const struct mptcp_addr_info *loc, 895 const struct mptcp_addr_info *rem); 896 void mptcp_pm_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); 897 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); 898 void mptcp_pm_new_connection(struct mptcp_sock *msk, const struct sock *ssk, int server_side); 899 void mptcp_pm_fully_established(struct mptcp_sock *msk, const struct sock *ssk); 900 bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk); 901 void mptcp_pm_connection_closed(struct mptcp_sock *msk); 902 void mptcp_pm_subflow_established(struct mptcp_sock *msk); 903 bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk); 904 void mptcp_pm_subflow_check_next(struct mptcp_sock *msk, const struct sock *ssk, 905 const struct mptcp_subflow_context *subflow); 906 void mptcp_pm_add_addr_received(const struct sock *ssk, 907 const struct mptcp_addr_info *addr); 908 void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk, 909 const struct mptcp_addr_info *addr); 910 void mptcp_pm_add_addr_send_ack(struct mptcp_sock *msk); 911 bool mptcp_pm_nl_is_init_remote_addr(struct mptcp_sock *msk, 912 const struct mptcp_addr_info *remote); 913 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk); 914 void mptcp_pm_rm_addr_received(struct mptcp_sock *msk, 915 const struct mptcp_rm_list *rm_list); 916 void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup); 917 void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq); 918 int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk, 919 struct mptcp_addr_info *addr, 920 struct mptcp_addr_info *rem, 921 u8 bkup); 922 bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk, 923 const struct mptcp_addr_info *addr); 924 void mptcp_pm_free_anno_list(struct mptcp_sock *msk); 925 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk); 926 struct mptcp_pm_add_entry * 927 mptcp_pm_del_add_timer(struct mptcp_sock *msk, 928 const struct mptcp_addr_info *addr, bool check_id); 929 struct mptcp_pm_add_entry * 930 mptcp_lookup_anno_list_by_saddr(const struct mptcp_sock *msk, 931 const struct mptcp_addr_info *addr); 932 int mptcp_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, 933 unsigned int id, 934 u8 *flags, int *ifindex); 935 int mptcp_pm_nl_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, unsigned int id, 936 u8 *flags, int *ifindex); 937 int mptcp_userspace_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, 938 unsigned int id, 939 u8 *flags, int *ifindex); 940 int mptcp_pm_set_flags(struct net *net, struct nlattr *token, 941 struct mptcp_pm_addr_entry *loc, 942 struct mptcp_pm_addr_entry *rem, u8 bkup); 943 int mptcp_pm_nl_set_flags(struct net *net, struct mptcp_pm_addr_entry *addr, u8 bkup); 944 int mptcp_userspace_pm_set_flags(struct net *net, struct nlattr *token, 945 struct mptcp_pm_addr_entry *loc, 946 struct mptcp_pm_addr_entry *rem, u8 bkup); 947 int mptcp_pm_announce_addr(struct mptcp_sock *msk, 948 const struct mptcp_addr_info *addr, 949 bool echo); 950 int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); 951 void mptcp_pm_remove_addrs(struct mptcp_sock *msk, struct list_head *rm_list); 952 953 void mptcp_free_local_addr_list(struct mptcp_sock *msk); 954 int mptcp_nl_cmd_announce(struct sk_buff *skb, struct genl_info *info); 955 int mptcp_nl_cmd_remove(struct sk_buff *skb, struct genl_info *info); 956 int mptcp_nl_cmd_sf_create(struct sk_buff *skb, struct genl_info *info); 957 int mptcp_nl_cmd_sf_destroy(struct sk_buff *skb, struct genl_info *info); 958 959 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk, 960 const struct sock *ssk, gfp_t gfp); 961 void mptcp_event_addr_announced(const struct sock *ssk, const struct mptcp_addr_info *info); 962 void mptcp_event_addr_removed(const struct mptcp_sock *msk, u8 id); 963 void mptcp_event_pm_listener(const struct sock *ssk, 964 enum mptcp_event_type event); 965 bool mptcp_userspace_pm_active(const struct mptcp_sock *msk); 966 967 void __mptcp_fastopen_gen_msk_ackseq(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow, 968 const struct mptcp_options_received *mp_opt); 969 void mptcp_fastopen_subflow_synack_set_params(struct mptcp_subflow_context *subflow, 970 struct request_sock *req); 971 972 static inline bool mptcp_pm_should_add_signal(struct mptcp_sock *msk) 973 { 974 return READ_ONCE(msk->pm.addr_signal) & 975 (BIT(MPTCP_ADD_ADDR_SIGNAL) | BIT(MPTCP_ADD_ADDR_ECHO)); 976 } 977 978 static inline bool mptcp_pm_should_add_signal_addr(struct mptcp_sock *msk) 979 { 980 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_SIGNAL); 981 } 982 983 static inline bool mptcp_pm_should_add_signal_echo(struct mptcp_sock *msk) 984 { 985 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_ECHO); 986 } 987 988 static inline bool mptcp_pm_should_rm_signal(struct mptcp_sock *msk) 989 { 990 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_RM_ADDR_SIGNAL); 991 } 992 993 static inline bool mptcp_pm_is_userspace(const struct mptcp_sock *msk) 994 { 995 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_USERSPACE; 996 } 997 998 static inline bool mptcp_pm_is_kernel(const struct mptcp_sock *msk) 999 { 1000 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_KERNEL; 1001 } 1002 1003 static inline unsigned int mptcp_add_addr_len(int family, bool echo, bool port) 1004 { 1005 u8 len = TCPOLEN_MPTCP_ADD_ADDR_BASE; 1006 1007 if (family == AF_INET6) 1008 len = TCPOLEN_MPTCP_ADD_ADDR6_BASE; 1009 if (!echo) 1010 len += MPTCPOPT_THMAC_LEN; 1011 /* account for 2 trailing 'nop' options */ 1012 if (port) 1013 len += TCPOLEN_MPTCP_PORT_LEN + TCPOLEN_MPTCP_PORT_ALIGN; 1014 1015 return len; 1016 } 1017 1018 static inline int mptcp_rm_addr_len(const struct mptcp_rm_list *rm_list) 1019 { 1020 if (rm_list->nr == 0 || rm_list->nr > MPTCP_RM_IDS_MAX) 1021 return -EINVAL; 1022 1023 return TCPOLEN_MPTCP_RM_ADDR_BASE + roundup(rm_list->nr - 1, 4) + 1; 1024 } 1025 1026 bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, const struct sk_buff *skb, 1027 unsigned int opt_size, unsigned int remaining, 1028 struct mptcp_addr_info *addr, bool *echo, 1029 bool *drop_other_suboptions); 1030 bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining, 1031 struct mptcp_rm_list *rm_list); 1032 int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc); 1033 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc); 1034 int mptcp_userspace_pm_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc); 1035 bool mptcp_pm_is_backup(struct mptcp_sock *msk, struct sock_common *skc); 1036 bool mptcp_pm_nl_is_backup(struct mptcp_sock *msk, struct mptcp_addr_info *skc); 1037 bool mptcp_userspace_pm_is_backup(struct mptcp_sock *msk, struct mptcp_addr_info *skc); 1038 1039 static inline u8 subflow_get_local_id(const struct mptcp_subflow_context *subflow) 1040 { 1041 int local_id = READ_ONCE(subflow->local_id); 1042 1043 if (local_id < 0) 1044 return 0; 1045 return local_id; 1046 } 1047 1048 void __init mptcp_pm_nl_init(void); 1049 void mptcp_pm_nl_work(struct mptcp_sock *msk); 1050 unsigned int mptcp_pm_get_add_addr_signal_max(const struct mptcp_sock *msk); 1051 unsigned int mptcp_pm_get_add_addr_accept_max(const struct mptcp_sock *msk); 1052 unsigned int mptcp_pm_get_subflows_max(const struct mptcp_sock *msk); 1053 unsigned int mptcp_pm_get_local_addr_max(const struct mptcp_sock *msk); 1054 1055 /* called under PM lock */ 1056 static inline void __mptcp_pm_close_subflow(struct mptcp_sock *msk) 1057 { 1058 if (--msk->pm.subflows < mptcp_pm_get_subflows_max(msk)) 1059 WRITE_ONCE(msk->pm.accept_subflow, true); 1060 } 1061 1062 static inline void mptcp_pm_close_subflow(struct mptcp_sock *msk) 1063 { 1064 spin_lock_bh(&msk->pm.lock); 1065 __mptcp_pm_close_subflow(msk); 1066 spin_unlock_bh(&msk->pm.lock); 1067 } 1068 1069 void mptcp_sockopt_sync(struct mptcp_sock *msk, struct sock *ssk); 1070 void mptcp_sockopt_sync_locked(struct mptcp_sock *msk, struct sock *ssk); 1071 1072 static inline struct mptcp_ext *mptcp_get_ext(const struct sk_buff *skb) 1073 { 1074 return (struct mptcp_ext *)skb_ext_find(skb, SKB_EXT_MPTCP); 1075 } 1076 1077 void mptcp_diag_subflow_init(struct tcp_ulp_ops *ops); 1078 1079 static inline bool __mptcp_check_fallback(const struct mptcp_sock *msk) 1080 { 1081 return test_bit(MPTCP_FALLBACK_DONE, &msk->flags); 1082 } 1083 1084 static inline bool mptcp_check_fallback(const struct sock *sk) 1085 { 1086 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 1087 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 1088 1089 return __mptcp_check_fallback(msk); 1090 } 1091 1092 static inline void __mptcp_do_fallback(struct mptcp_sock *msk) 1093 { 1094 if (test_bit(MPTCP_FALLBACK_DONE, &msk->flags)) { 1095 pr_debug("TCP fallback already done (msk=%p)\n", msk); 1096 return; 1097 } 1098 set_bit(MPTCP_FALLBACK_DONE, &msk->flags); 1099 } 1100 1101 static inline void mptcp_do_fallback(struct sock *ssk) 1102 { 1103 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 1104 struct sock *sk = subflow->conn; 1105 struct mptcp_sock *msk; 1106 1107 msk = mptcp_sk(sk); 1108 __mptcp_do_fallback(msk); 1109 if (READ_ONCE(msk->snd_data_fin_enable) && !(ssk->sk_shutdown & SEND_SHUTDOWN)) { 1110 gfp_t saved_allocation = ssk->sk_allocation; 1111 1112 /* we are in a atomic (BH) scope, override ssk default for data 1113 * fin allocation 1114 */ 1115 ssk->sk_allocation = GFP_ATOMIC; 1116 ssk->sk_shutdown |= SEND_SHUTDOWN; 1117 tcp_shutdown(ssk, SEND_SHUTDOWN); 1118 ssk->sk_allocation = saved_allocation; 1119 } 1120 } 1121 1122 #define pr_fallback(a) pr_debug("%s:fallback to TCP (msk=%p)\n", __func__, a) 1123 1124 static inline bool mptcp_check_infinite_map(struct sk_buff *skb) 1125 { 1126 struct mptcp_ext *mpext; 1127 1128 mpext = skb ? mptcp_get_ext(skb) : NULL; 1129 if (mpext && mpext->infinite_map) 1130 return true; 1131 1132 return false; 1133 } 1134 1135 static inline bool is_active_ssk(struct mptcp_subflow_context *subflow) 1136 { 1137 return (subflow->request_mptcp || subflow->request_join); 1138 } 1139 1140 static inline bool subflow_simultaneous_connect(struct sock *sk) 1141 { 1142 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 1143 1144 return (1 << sk->sk_state) & 1145 (TCPF_ESTABLISHED | TCPF_FIN_WAIT1 | TCPF_FIN_WAIT2 | TCPF_CLOSING) && 1146 is_active_ssk(subflow) && 1147 !subflow->conn_finished; 1148 } 1149 1150 #ifdef CONFIG_SYN_COOKIES 1151 void subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 1152 struct sk_buff *skb); 1153 bool mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 1154 struct sk_buff *skb); 1155 void __init mptcp_join_cookie_init(void); 1156 #else 1157 static inline void 1158 subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 1159 struct sk_buff *skb) {} 1160 static inline bool 1161 mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 1162 struct sk_buff *skb) 1163 { 1164 return false; 1165 } 1166 1167 static inline void mptcp_join_cookie_init(void) {} 1168 #endif 1169 1170 #endif /* __MPTCP_PROTOCOL_H */ 1171