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 struct_group(status, 153 u16 suboptions; 154 u16 use_map:1, 155 dsn64:1, 156 data_fin:1, 157 use_ack:1, 158 ack64:1, 159 mpc_map:1, 160 reset_reason:4, 161 reset_transient:1, 162 echo:1, 163 backup:1, 164 deny_join_id0:1, 165 __unused:2; 166 ); 167 u8 join_id; 168 u32 token; 169 u32 nonce; 170 u64 thmac; 171 u8 hmac[MPTCPOPT_HMAC_LEN]; 172 struct mptcp_addr_info addr; 173 struct mptcp_rm_list rm_list; 174 u64 ahmac; 175 u64 fail_seq; 176 }; 177 178 static inline __be32 mptcp_option(u8 subopt, u8 len, u8 nib, u8 field) 179 { 180 return htonl((TCPOPT_MPTCP << 24) | (len << 16) | (subopt << 12) | 181 ((nib & 0xF) << 8) | field); 182 } 183 184 enum mptcp_pm_status { 185 MPTCP_PM_ADD_ADDR_RECEIVED, 186 MPTCP_PM_ADD_ADDR_SEND_ACK, 187 MPTCP_PM_RM_ADDR_RECEIVED, 188 MPTCP_PM_ESTABLISHED, 189 MPTCP_PM_SUBFLOW_ESTABLISHED, 190 MPTCP_PM_ALREADY_ESTABLISHED, /* persistent status, set after ESTABLISHED event */ 191 MPTCP_PM_MPC_ENDPOINT_ACCOUNTED /* persistent status, set after MPC local address is 192 * accounted int id_avail_bitmap 193 */ 194 }; 195 196 enum mptcp_pm_type { 197 MPTCP_PM_TYPE_KERNEL = 0, 198 MPTCP_PM_TYPE_USERSPACE, 199 200 __MPTCP_PM_TYPE_NR, 201 __MPTCP_PM_TYPE_MAX = __MPTCP_PM_TYPE_NR - 1, 202 }; 203 204 /* Status bits below MPTCP_PM_ALREADY_ESTABLISHED need pm worker actions */ 205 #define MPTCP_PM_WORK_MASK ((1 << MPTCP_PM_ALREADY_ESTABLISHED) - 1) 206 207 enum mptcp_addr_signal_status { 208 MPTCP_ADD_ADDR_SIGNAL, 209 MPTCP_ADD_ADDR_ECHO, 210 MPTCP_RM_ADDR_SIGNAL, 211 }; 212 213 /* max value of mptcp_addr_info.id */ 214 #define MPTCP_PM_MAX_ADDR_ID U8_MAX 215 216 struct mptcp_pm_data { 217 struct mptcp_addr_info local; 218 struct mptcp_addr_info remote; 219 struct list_head anno_list; 220 struct list_head userspace_pm_local_addr_list; 221 222 spinlock_t lock; /*protects the whole PM data */ 223 224 u8 addr_signal; 225 bool server_side; 226 bool work_pending; 227 bool accept_addr; 228 bool accept_subflow; 229 bool remote_deny_join_id0; 230 u8 add_addr_signaled; 231 u8 add_addr_accepted; 232 u8 local_addr_used; 233 u8 pm_type; 234 u8 subflows; 235 u8 status; 236 DECLARE_BITMAP(id_avail_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); 237 struct mptcp_rm_list rm_list_tx; 238 struct mptcp_rm_list rm_list_rx; 239 }; 240 241 struct mptcp_pm_addr_entry { 242 struct list_head list; 243 struct mptcp_addr_info addr; 244 u8 flags; 245 int ifindex; 246 struct socket *lsk; 247 }; 248 249 struct mptcp_data_frag { 250 struct list_head list; 251 u64 data_seq; 252 u16 data_len; 253 u16 offset; 254 u16 overhead; 255 u16 already_sent; 256 struct page *page; 257 }; 258 259 /* MPTCP connection sock */ 260 struct mptcp_sock { 261 /* inet_connection_sock must be the first member */ 262 struct inet_connection_sock sk; 263 u64 local_key; 264 u64 remote_key; 265 u64 write_seq; 266 u64 bytes_sent; 267 u64 snd_nxt; 268 u64 bytes_received; 269 u64 ack_seq; 270 atomic64_t rcv_wnd_sent; 271 u64 rcv_data_fin_seq; 272 u64 bytes_retrans; 273 u64 bytes_consumed; 274 int rmem_fwd_alloc; 275 int snd_burst; 276 int old_wspace; 277 u64 recovery_snd_nxt; /* in recovery mode accept up to this seq; 278 * recovery related fields are under data_lock 279 * protection 280 */ 281 u64 bytes_acked; 282 u64 snd_una; 283 u64 wnd_end; 284 unsigned long timer_ival; 285 u32 token; 286 int rmem_released; 287 unsigned long flags; 288 unsigned long cb_flags; 289 bool recovery; /* closing subflow write queue reinjected */ 290 bool can_ack; 291 bool fully_established; 292 bool rcv_data_fin; 293 bool snd_data_fin_enable; 294 bool rcv_fastclose; 295 bool use_64bit_ack; /* Set when we received a 64-bit DSN */ 296 bool csum_enabled; 297 bool allow_infinite_fallback; 298 u8 pending_state; /* A subflow asked to set this sk_state, 299 * protected by the msk data lock 300 */ 301 u8 mpc_endpoint_id; 302 u8 recvmsg_inq:1, 303 cork:1, 304 nodelay:1, 305 fastopening:1, 306 in_accept_queue:1, 307 free_first:1, 308 rcvspace_init:1; 309 int keepalive_cnt; 310 int keepalive_idle; 311 int keepalive_intvl; 312 struct work_struct work; 313 struct sk_buff *ooo_last_skb; 314 struct rb_root out_of_order_queue; 315 struct sk_buff_head receive_queue; 316 struct list_head conn_list; 317 struct list_head rtx_queue; 318 struct mptcp_data_frag *first_pending; 319 struct list_head join_list; 320 struct sock *first; /* The mptcp ops can safely dereference, using suitable 321 * ONCE annotation, the subflow outside the socket 322 * lock as such sock is freed after close(). 323 */ 324 struct mptcp_pm_data pm; 325 struct mptcp_sched_ops *sched; 326 struct { 327 u32 space; /* bytes copied in last measurement window */ 328 u32 copied; /* bytes copied in this measurement window */ 329 u64 time; /* start time of measurement window */ 330 u64 rtt_us; /* last maximum rtt of subflows */ 331 } rcvq_space; 332 u8 scaling_ratio; 333 334 u32 subflow_id; 335 u32 setsockopt_seq; 336 char ca_name[TCP_CA_NAME_MAX]; 337 }; 338 339 #define mptcp_data_lock(sk) spin_lock_bh(&(sk)->sk_lock.slock) 340 #define mptcp_data_unlock(sk) spin_unlock_bh(&(sk)->sk_lock.slock) 341 342 #define mptcp_for_each_subflow(__msk, __subflow) \ 343 list_for_each_entry(__subflow, &((__msk)->conn_list), node) 344 #define mptcp_for_each_subflow_safe(__msk, __subflow, __tmp) \ 345 list_for_each_entry_safe(__subflow, __tmp, &((__msk)->conn_list), node) 346 347 static inline void msk_owned_by_me(const struct mptcp_sock *msk) 348 { 349 sock_owned_by_me((const struct sock *)msk); 350 } 351 352 #define mptcp_sk(ptr) container_of_const(ptr, struct mptcp_sock, sk.icsk_inet.sk) 353 354 /* the msk socket don't use the backlog, also account for the bulk 355 * free memory 356 */ 357 static inline int __mptcp_rmem(const struct sock *sk) 358 { 359 return atomic_read(&sk->sk_rmem_alloc) - READ_ONCE(mptcp_sk(sk)->rmem_released); 360 } 361 362 static inline int mptcp_win_from_space(const struct sock *sk, int space) 363 { 364 return __tcp_win_from_space(mptcp_sk(sk)->scaling_ratio, space); 365 } 366 367 static inline int __mptcp_space(const struct sock *sk) 368 { 369 return mptcp_win_from_space(sk, READ_ONCE(sk->sk_rcvbuf) - __mptcp_rmem(sk)); 370 } 371 372 static inline struct mptcp_data_frag *mptcp_send_head(const struct sock *sk) 373 { 374 const struct mptcp_sock *msk = mptcp_sk(sk); 375 376 return READ_ONCE(msk->first_pending); 377 } 378 379 static inline struct mptcp_data_frag *mptcp_send_next(struct sock *sk) 380 { 381 struct mptcp_sock *msk = mptcp_sk(sk); 382 struct mptcp_data_frag *cur; 383 384 cur = msk->first_pending; 385 return list_is_last(&cur->list, &msk->rtx_queue) ? NULL : 386 list_next_entry(cur, list); 387 } 388 389 static inline struct mptcp_data_frag *mptcp_pending_tail(const struct sock *sk) 390 { 391 const struct mptcp_sock *msk = mptcp_sk(sk); 392 393 if (!msk->first_pending) 394 return NULL; 395 396 if (WARN_ON_ONCE(list_empty(&msk->rtx_queue))) 397 return NULL; 398 399 return list_last_entry(&msk->rtx_queue, struct mptcp_data_frag, list); 400 } 401 402 static inline struct mptcp_data_frag *mptcp_rtx_head(struct sock *sk) 403 { 404 struct mptcp_sock *msk = mptcp_sk(sk); 405 406 if (msk->snd_una == READ_ONCE(msk->snd_nxt)) 407 return NULL; 408 409 return list_first_entry_or_null(&msk->rtx_queue, struct mptcp_data_frag, list); 410 } 411 412 struct csum_pseudo_header { 413 __be64 data_seq; 414 __be32 subflow_seq; 415 __be16 data_len; 416 __sum16 csum; 417 }; 418 419 struct mptcp_subflow_request_sock { 420 struct tcp_request_sock sk; 421 u16 mp_capable : 1, 422 mp_join : 1, 423 backup : 1, 424 request_bkup : 1, 425 csum_reqd : 1, 426 allow_join_id0 : 1; 427 u8 local_id; 428 u8 remote_id; 429 u64 local_key; 430 u64 idsn; 431 u32 token; 432 u32 ssn_offset; 433 u64 thmac; 434 u32 local_nonce; 435 u32 remote_nonce; 436 struct mptcp_sock *msk; 437 struct hlist_nulls_node token_node; 438 }; 439 440 static inline struct mptcp_subflow_request_sock * 441 mptcp_subflow_rsk(const struct request_sock *rsk) 442 { 443 return (struct mptcp_subflow_request_sock *)rsk; 444 } 445 446 enum mptcp_data_avail { 447 MPTCP_SUBFLOW_NODATA, 448 MPTCP_SUBFLOW_DATA_AVAIL, 449 }; 450 451 struct mptcp_delegated_action { 452 struct napi_struct napi; 453 struct list_head head; 454 }; 455 456 DECLARE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions); 457 458 #define MPTCP_DELEGATE_SCHEDULED 0 459 #define MPTCP_DELEGATE_SEND 1 460 #define MPTCP_DELEGATE_ACK 2 461 #define MPTCP_DELEGATE_SNDBUF 3 462 463 #define MPTCP_DELEGATE_ACTIONS_MASK (~BIT(MPTCP_DELEGATE_SCHEDULED)) 464 /* MPTCP subflow context */ 465 struct mptcp_subflow_context { 466 struct list_head node;/* conn_list of subflows */ 467 468 struct_group(reset, 469 470 unsigned long avg_pacing_rate; /* protected by msk socket lock */ 471 u64 local_key; 472 u64 remote_key; 473 u64 idsn; 474 u64 map_seq; 475 u32 snd_isn; 476 u32 token; 477 u32 rel_write_seq; 478 u32 map_subflow_seq; 479 u32 ssn_offset; 480 u32 map_data_len; 481 __wsum map_data_csum; 482 u32 map_csum_len; 483 u32 request_mptcp : 1, /* send MP_CAPABLE */ 484 request_join : 1, /* send MP_JOIN */ 485 request_bkup : 1, 486 mp_capable : 1, /* remote is MPTCP capable */ 487 mp_join : 1, /* remote is JOINing */ 488 fully_established : 1, /* path validated */ 489 pm_notified : 1, /* PM hook called for established status */ 490 conn_finished : 1, 491 map_valid : 1, 492 map_csum_reqd : 1, 493 map_data_fin : 1, 494 mpc_map : 1, 495 backup : 1, 496 send_mp_prio : 1, 497 send_mp_fail : 1, 498 send_fastclose : 1, 499 send_infinite_map : 1, 500 remote_key_valid : 1, /* received the peer key from */ 501 disposable : 1, /* ctx can be free at ulp release time */ 502 stale : 1, /* unable to snd/rcv data, do not use for xmit */ 503 valid_csum_seen : 1, /* at least one csum validated */ 504 is_mptfo : 1, /* subflow is doing TFO */ 505 close_event_done : 1, /* has done the post-closed part */ 506 __unused : 9; 507 enum mptcp_data_avail data_avail; 508 bool scheduled; 509 bool pm_listener; /* a listener managed by the kernel PM? */ 510 u32 remote_nonce; 511 u64 thmac; 512 u32 local_nonce; 513 u32 remote_token; 514 union { 515 u8 hmac[MPTCPOPT_HMAC_LEN]; /* MPJ subflow only */ 516 u64 iasn; /* initial ack sequence number, MPC subflows only */ 517 }; 518 s16 local_id; /* if negative not initialized yet */ 519 u8 remote_id; 520 u8 reset_seen:1; 521 u8 reset_transient:1; 522 u8 reset_reason:4; 523 u8 stale_count; 524 525 u32 subflow_id; 526 527 long delegated_status; 528 unsigned long fail_tout; 529 530 ); 531 532 struct list_head delegated_node; /* link into delegated_action, protected by local BH */ 533 534 u32 setsockopt_seq; 535 u32 stale_rcv_tstamp; 536 int cached_sndbuf; /* sndbuf size when last synced with the msk sndbuf, 537 * protected by the msk socket lock 538 */ 539 540 struct sock *tcp_sock; /* tcp sk backpointer */ 541 struct sock *conn; /* parent mptcp_sock */ 542 const struct inet_connection_sock_af_ops *icsk_af_ops; 543 void (*tcp_state_change)(struct sock *sk); 544 void (*tcp_error_report)(struct sock *sk); 545 546 struct rcu_head rcu; 547 }; 548 549 static inline struct mptcp_subflow_context * 550 mptcp_subflow_ctx(const struct sock *sk) 551 { 552 struct inet_connection_sock *icsk = inet_csk(sk); 553 554 /* Use RCU on icsk_ulp_data only for sock diag code */ 555 return (__force struct mptcp_subflow_context *)icsk->icsk_ulp_data; 556 } 557 558 static inline struct sock * 559 mptcp_subflow_tcp_sock(const struct mptcp_subflow_context *subflow) 560 { 561 return subflow->tcp_sock; 562 } 563 564 static inline void 565 mptcp_subflow_ctx_reset(struct mptcp_subflow_context *subflow) 566 { 567 memset(&subflow->reset, 0, sizeof(subflow->reset)); 568 subflow->request_mptcp = 1; 569 WRITE_ONCE(subflow->local_id, -1); 570 } 571 572 static inline u64 573 mptcp_subflow_get_map_offset(const struct mptcp_subflow_context *subflow) 574 { 575 return tcp_sk(mptcp_subflow_tcp_sock(subflow))->copied_seq - 576 subflow->ssn_offset - 577 subflow->map_subflow_seq; 578 } 579 580 static inline u64 581 mptcp_subflow_get_mapped_dsn(const struct mptcp_subflow_context *subflow) 582 { 583 return subflow->map_seq + mptcp_subflow_get_map_offset(subflow); 584 } 585 586 void mptcp_subflow_process_delegated(struct sock *ssk, long actions); 587 588 static inline void mptcp_subflow_delegate(struct mptcp_subflow_context *subflow, int action) 589 { 590 long old, set_bits = BIT(MPTCP_DELEGATE_SCHEDULED) | BIT(action); 591 struct mptcp_delegated_action *delegated; 592 bool schedule; 593 594 /* the caller held the subflow bh socket lock */ 595 lockdep_assert_in_softirq(); 596 597 /* The implied barrier pairs with tcp_release_cb_override() 598 * mptcp_napi_poll(), and ensures the below list check sees list 599 * updates done prior to delegated status bits changes 600 */ 601 old = set_mask_bits(&subflow->delegated_status, 0, set_bits); 602 if (!(old & BIT(MPTCP_DELEGATE_SCHEDULED))) { 603 if (WARN_ON_ONCE(!list_empty(&subflow->delegated_node))) 604 return; 605 606 delegated = this_cpu_ptr(&mptcp_delegated_actions); 607 schedule = list_empty(&delegated->head); 608 list_add_tail(&subflow->delegated_node, &delegated->head); 609 sock_hold(mptcp_subflow_tcp_sock(subflow)); 610 if (schedule) 611 napi_schedule(&delegated->napi); 612 } 613 } 614 615 static inline struct mptcp_subflow_context * 616 mptcp_subflow_delegated_next(struct mptcp_delegated_action *delegated) 617 { 618 struct mptcp_subflow_context *ret; 619 620 if (list_empty(&delegated->head)) 621 return NULL; 622 623 ret = list_first_entry(&delegated->head, struct mptcp_subflow_context, delegated_node); 624 list_del_init(&ret->delegated_node); 625 return ret; 626 } 627 628 int mptcp_is_enabled(const struct net *net); 629 unsigned int mptcp_get_add_addr_timeout(const struct net *net); 630 int mptcp_is_checksum_enabled(const struct net *net); 631 int mptcp_allow_join_id0(const struct net *net); 632 unsigned int mptcp_stale_loss_cnt(const struct net *net); 633 int mptcp_get_pm_type(const struct net *net); 634 const char *mptcp_get_scheduler(const struct net *net); 635 void __mptcp_subflow_fully_established(struct mptcp_sock *msk, 636 struct mptcp_subflow_context *subflow, 637 const struct mptcp_options_received *mp_opt); 638 bool __mptcp_retransmit_pending_data(struct sock *sk); 639 void mptcp_check_and_set_pending(struct sock *sk); 640 void __mptcp_push_pending(struct sock *sk, unsigned int flags); 641 bool mptcp_subflow_data_available(struct sock *sk); 642 void __init mptcp_subflow_init(void); 643 void mptcp_subflow_shutdown(struct sock *sk, struct sock *ssk, int how); 644 void mptcp_close_ssk(struct sock *sk, struct sock *ssk, 645 struct mptcp_subflow_context *subflow); 646 void __mptcp_subflow_send_ack(struct sock *ssk); 647 void mptcp_subflow_reset(struct sock *ssk); 648 void mptcp_subflow_queue_clean(struct sock *sk, struct sock *ssk); 649 void mptcp_sock_graft(struct sock *sk, struct socket *parent); 650 struct sock *__mptcp_nmpc_sk(struct mptcp_sock *msk); 651 bool __mptcp_close(struct sock *sk, long timeout); 652 void mptcp_cancel_work(struct sock *sk); 653 void __mptcp_unaccepted_force_close(struct sock *sk); 654 void mptcp_set_owner_r(struct sk_buff *skb, struct sock *sk); 655 void mptcp_set_state(struct sock *sk, int state); 656 657 bool mptcp_addresses_equal(const struct mptcp_addr_info *a, 658 const struct mptcp_addr_info *b, bool use_port); 659 void mptcp_local_address(const struct sock_common *skc, struct mptcp_addr_info *addr); 660 661 /* called with sk socket lock held */ 662 int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_addr_info *loc, 663 const struct mptcp_addr_info *remote); 664 int mptcp_subflow_create_socket(struct sock *sk, unsigned short family, 665 struct socket **new_sock); 666 void mptcp_info2sockaddr(const struct mptcp_addr_info *info, 667 struct sockaddr_storage *addr, 668 unsigned short family); 669 struct mptcp_sched_ops *mptcp_sched_find(const char *name); 670 int mptcp_register_scheduler(struct mptcp_sched_ops *sched); 671 void mptcp_unregister_scheduler(struct mptcp_sched_ops *sched); 672 void mptcp_sched_init(void); 673 int mptcp_init_sched(struct mptcp_sock *msk, 674 struct mptcp_sched_ops *sched); 675 void mptcp_release_sched(struct mptcp_sock *msk); 676 void mptcp_subflow_set_scheduled(struct mptcp_subflow_context *subflow, 677 bool scheduled); 678 struct sock *mptcp_subflow_get_send(struct mptcp_sock *msk); 679 struct sock *mptcp_subflow_get_retrans(struct mptcp_sock *msk); 680 int mptcp_sched_get_send(struct mptcp_sock *msk); 681 int mptcp_sched_get_retrans(struct mptcp_sock *msk); 682 683 static inline u64 mptcp_data_avail(const struct mptcp_sock *msk) 684 { 685 return READ_ONCE(msk->bytes_received) - READ_ONCE(msk->bytes_consumed); 686 } 687 688 static inline bool mptcp_epollin_ready(const struct sock *sk) 689 { 690 u64 data_avail = mptcp_data_avail(mptcp_sk(sk)); 691 692 if (!data_avail) 693 return false; 694 695 /* mptcp doesn't have to deal with small skbs in the receive queue, 696 * as it can always coalesce them 697 */ 698 return (data_avail >= sk->sk_rcvlowat) || 699 (mem_cgroup_sockets_enabled && sk->sk_memcg && 700 mem_cgroup_under_socket_pressure(sk->sk_memcg)) || 701 READ_ONCE(tcp_memory_pressure); 702 } 703 704 int mptcp_set_rcvlowat(struct sock *sk, int val); 705 706 static inline bool __tcp_can_send(const struct sock *ssk) 707 { 708 /* only send if our side has not closed yet */ 709 return ((1 << inet_sk_state_load(ssk)) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)); 710 } 711 712 static inline bool __mptcp_subflow_active(struct mptcp_subflow_context *subflow) 713 { 714 /* can't send if JOIN hasn't completed yet (i.e. is usable for mptcp) */ 715 if (subflow->request_join && !subflow->fully_established) 716 return false; 717 718 return __tcp_can_send(mptcp_subflow_tcp_sock(subflow)); 719 } 720 721 void mptcp_subflow_set_active(struct mptcp_subflow_context *subflow); 722 723 bool mptcp_subflow_active(struct mptcp_subflow_context *subflow); 724 725 void mptcp_subflow_drop_ctx(struct sock *ssk); 726 727 static inline void mptcp_subflow_tcp_fallback(struct sock *sk, 728 struct mptcp_subflow_context *ctx) 729 { 730 sk->sk_data_ready = sock_def_readable; 731 sk->sk_state_change = ctx->tcp_state_change; 732 sk->sk_write_space = sk_stream_write_space; 733 sk->sk_error_report = ctx->tcp_error_report; 734 735 inet_csk(sk)->icsk_af_ops = ctx->icsk_af_ops; 736 } 737 738 void __init mptcp_proto_init(void); 739 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 740 int __init mptcp_proto_v6_init(void); 741 #endif 742 743 struct sock *mptcp_sk_clone_init(const struct sock *sk, 744 const struct mptcp_options_received *mp_opt, 745 struct sock *ssk, 746 struct request_sock *req); 747 void mptcp_get_options(const struct sk_buff *skb, 748 struct mptcp_options_received *mp_opt); 749 750 void mptcp_finish_connect(struct sock *sk); 751 void __mptcp_sync_state(struct sock *sk, int state); 752 void mptcp_reset_tout_timer(struct mptcp_sock *msk, unsigned long fail_tout); 753 754 static inline void mptcp_stop_tout_timer(struct sock *sk) 755 { 756 if (!inet_csk(sk)->icsk_mtup.probe_timestamp) 757 return; 758 759 sk_stop_timer(sk, &sk->sk_timer); 760 inet_csk(sk)->icsk_mtup.probe_timestamp = 0; 761 } 762 763 static inline void mptcp_set_close_tout(struct sock *sk, unsigned long tout) 764 { 765 /* avoid 0 timestamp, as that means no close timeout */ 766 inet_csk(sk)->icsk_mtup.probe_timestamp = tout ? : 1; 767 } 768 769 static inline void mptcp_start_tout_timer(struct sock *sk) 770 { 771 mptcp_set_close_tout(sk, tcp_jiffies32); 772 mptcp_reset_tout_timer(mptcp_sk(sk), 0); 773 } 774 775 static inline bool mptcp_is_fully_established(struct sock *sk) 776 { 777 return inet_sk_state_load(sk) == TCP_ESTABLISHED && 778 READ_ONCE(mptcp_sk(sk)->fully_established); 779 } 780 781 void mptcp_rcv_space_init(struct mptcp_sock *msk, const struct sock *ssk); 782 void mptcp_data_ready(struct sock *sk, struct sock *ssk); 783 bool mptcp_finish_join(struct sock *sk); 784 bool mptcp_schedule_work(struct sock *sk); 785 int mptcp_setsockopt(struct sock *sk, int level, int optname, 786 sockptr_t optval, unsigned int optlen); 787 int mptcp_getsockopt(struct sock *sk, int level, int optname, 788 char __user *optval, int __user *option); 789 790 u64 __mptcp_expand_seq(u64 old_seq, u64 cur_seq); 791 static inline u64 mptcp_expand_seq(u64 old_seq, u64 cur_seq, bool use_64bit) 792 { 793 if (use_64bit) 794 return cur_seq; 795 796 return __mptcp_expand_seq(old_seq, cur_seq); 797 } 798 void __mptcp_check_push(struct sock *sk, struct sock *ssk); 799 void __mptcp_data_acked(struct sock *sk); 800 void __mptcp_error_report(struct sock *sk); 801 bool mptcp_update_rcv_data_fin(struct mptcp_sock *msk, u64 data_fin_seq, bool use_64bit); 802 static inline bool mptcp_data_fin_enabled(const struct mptcp_sock *msk) 803 { 804 return READ_ONCE(msk->snd_data_fin_enable) && 805 READ_ONCE(msk->write_seq) == READ_ONCE(msk->snd_nxt); 806 } 807 808 static inline void mptcp_write_space(struct sock *sk) 809 { 810 if (sk_stream_is_writeable(sk)) { 811 /* pairs with memory barrier in mptcp_poll */ 812 smp_mb(); 813 if (test_and_clear_bit(MPTCP_NOSPACE, &mptcp_sk(sk)->flags)) 814 sk_stream_write_space(sk); 815 } 816 } 817 818 static inline void __mptcp_sync_sndbuf(struct sock *sk) 819 { 820 struct mptcp_subflow_context *subflow; 821 int ssk_sndbuf, new_sndbuf; 822 823 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) 824 return; 825 826 new_sndbuf = sock_net(sk)->ipv4.sysctl_tcp_wmem[0]; 827 mptcp_for_each_subflow(mptcp_sk(sk), subflow) { 828 ssk_sndbuf = READ_ONCE(mptcp_subflow_tcp_sock(subflow)->sk_sndbuf); 829 830 subflow->cached_sndbuf = ssk_sndbuf; 831 new_sndbuf += ssk_sndbuf; 832 } 833 834 /* the msk max wmem limit is <nr_subflows> * tcp wmem[2] */ 835 WRITE_ONCE(sk->sk_sndbuf, new_sndbuf); 836 mptcp_write_space(sk); 837 } 838 839 /* The called held both the msk socket and the subflow socket locks, 840 * possibly under BH 841 */ 842 static inline void __mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk) 843 { 844 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 845 846 if (READ_ONCE(ssk->sk_sndbuf) != subflow->cached_sndbuf) 847 __mptcp_sync_sndbuf(sk); 848 } 849 850 /* the caller held only the subflow socket lock, either in process or 851 * BH context. Additionally this can be called under the msk data lock, 852 * so we can't acquire such lock here: let the delegate action acquires 853 * the needed locks in suitable order. 854 */ 855 static inline void mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk) 856 { 857 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 858 859 if (likely(READ_ONCE(ssk->sk_sndbuf) == subflow->cached_sndbuf)) 860 return; 861 862 local_bh_disable(); 863 mptcp_subflow_delegate(subflow, MPTCP_DELEGATE_SNDBUF); 864 local_bh_enable(); 865 } 866 867 void mptcp_destroy_common(struct mptcp_sock *msk, unsigned int flags); 868 869 #define MPTCP_TOKEN_MAX_RETRIES 4 870 871 void __init mptcp_token_init(void); 872 static inline void mptcp_token_init_request(struct request_sock *req) 873 { 874 mptcp_subflow_rsk(req)->token_node.pprev = NULL; 875 } 876 877 int mptcp_token_new_request(struct request_sock *req); 878 void mptcp_token_destroy_request(struct request_sock *req); 879 int mptcp_token_new_connect(struct sock *ssk); 880 void mptcp_token_accept(struct mptcp_subflow_request_sock *r, 881 struct mptcp_sock *msk); 882 bool mptcp_token_exists(u32 token); 883 struct mptcp_sock *mptcp_token_get_sock(struct net *net, u32 token); 884 struct mptcp_sock *mptcp_token_iter_next(const struct net *net, long *s_slot, 885 long *s_num); 886 void mptcp_token_destroy(struct mptcp_sock *msk); 887 888 void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn); 889 890 void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u8 *msg, int len, void *hmac); 891 __sum16 __mptcp_make_csum(u64 data_seq, u32 subflow_seq, u16 data_len, __wsum sum); 892 893 void __init mptcp_pm_init(void); 894 void mptcp_pm_data_init(struct mptcp_sock *msk); 895 void mptcp_pm_data_reset(struct mptcp_sock *msk); 896 int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info, 897 struct mptcp_addr_info *addr); 898 int mptcp_pm_parse_entry(struct nlattr *attr, struct genl_info *info, 899 bool require_family, 900 struct mptcp_pm_addr_entry *entry); 901 bool mptcp_pm_addr_families_match(const struct sock *sk, 902 const struct mptcp_addr_info *loc, 903 const struct mptcp_addr_info *rem); 904 void mptcp_pm_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); 905 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); 906 void mptcp_pm_new_connection(struct mptcp_sock *msk, const struct sock *ssk, int server_side); 907 void mptcp_pm_fully_established(struct mptcp_sock *msk, const struct sock *ssk); 908 bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk); 909 void mptcp_pm_connection_closed(struct mptcp_sock *msk); 910 void mptcp_pm_subflow_established(struct mptcp_sock *msk); 911 bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk); 912 void mptcp_pm_subflow_check_next(struct mptcp_sock *msk, const struct sock *ssk, 913 const struct mptcp_subflow_context *subflow); 914 void mptcp_pm_add_addr_received(const struct sock *ssk, 915 const struct mptcp_addr_info *addr); 916 void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk, 917 const struct mptcp_addr_info *addr); 918 void mptcp_pm_add_addr_send_ack(struct mptcp_sock *msk); 919 bool mptcp_pm_nl_is_init_remote_addr(struct mptcp_sock *msk, 920 const struct mptcp_addr_info *remote); 921 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk); 922 void mptcp_pm_rm_addr_received(struct mptcp_sock *msk, 923 const struct mptcp_rm_list *rm_list); 924 void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup); 925 void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq); 926 int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk, 927 struct mptcp_addr_info *addr, 928 struct mptcp_addr_info *rem, 929 u8 bkup); 930 bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk, 931 const struct mptcp_addr_info *addr); 932 void mptcp_pm_free_anno_list(struct mptcp_sock *msk); 933 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk); 934 struct mptcp_pm_add_entry * 935 mptcp_pm_del_add_timer(struct mptcp_sock *msk, 936 const struct mptcp_addr_info *addr, bool check_id); 937 struct mptcp_pm_add_entry * 938 mptcp_lookup_anno_list_by_saddr(const struct mptcp_sock *msk, 939 const struct mptcp_addr_info *addr); 940 int mptcp_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, 941 unsigned int id, 942 u8 *flags, int *ifindex); 943 int mptcp_pm_nl_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, unsigned int id, 944 u8 *flags, int *ifindex); 945 int mptcp_userspace_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, 946 unsigned int id, 947 u8 *flags, int *ifindex); 948 int mptcp_pm_set_flags(struct net *net, struct nlattr *token, 949 struct mptcp_pm_addr_entry *loc, 950 struct mptcp_pm_addr_entry *rem, u8 bkup); 951 int mptcp_pm_nl_set_flags(struct net *net, struct mptcp_pm_addr_entry *addr, u8 bkup); 952 int mptcp_userspace_pm_set_flags(struct net *net, struct nlattr *token, 953 struct mptcp_pm_addr_entry *loc, 954 struct mptcp_pm_addr_entry *rem, u8 bkup); 955 int mptcp_pm_announce_addr(struct mptcp_sock *msk, 956 const struct mptcp_addr_info *addr, 957 bool echo); 958 int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); 959 void mptcp_pm_remove_addrs(struct mptcp_sock *msk, struct list_head *rm_list); 960 961 void mptcp_free_local_addr_list(struct mptcp_sock *msk); 962 int mptcp_nl_cmd_announce(struct sk_buff *skb, struct genl_info *info); 963 int mptcp_nl_cmd_remove(struct sk_buff *skb, struct genl_info *info); 964 int mptcp_nl_cmd_sf_create(struct sk_buff *skb, struct genl_info *info); 965 int mptcp_nl_cmd_sf_destroy(struct sk_buff *skb, struct genl_info *info); 966 967 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk, 968 const struct sock *ssk, gfp_t gfp); 969 void mptcp_event_addr_announced(const struct sock *ssk, const struct mptcp_addr_info *info); 970 void mptcp_event_addr_removed(const struct mptcp_sock *msk, u8 id); 971 void mptcp_event_pm_listener(const struct sock *ssk, 972 enum mptcp_event_type event); 973 bool mptcp_userspace_pm_active(const struct mptcp_sock *msk); 974 975 void __mptcp_fastopen_gen_msk_ackseq(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow, 976 const struct mptcp_options_received *mp_opt); 977 void mptcp_fastopen_subflow_synack_set_params(struct mptcp_subflow_context *subflow, 978 struct request_sock *req); 979 980 static inline bool mptcp_pm_should_add_signal(struct mptcp_sock *msk) 981 { 982 return READ_ONCE(msk->pm.addr_signal) & 983 (BIT(MPTCP_ADD_ADDR_SIGNAL) | BIT(MPTCP_ADD_ADDR_ECHO)); 984 } 985 986 static inline bool mptcp_pm_should_add_signal_addr(struct mptcp_sock *msk) 987 { 988 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_SIGNAL); 989 } 990 991 static inline bool mptcp_pm_should_add_signal_echo(struct mptcp_sock *msk) 992 { 993 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_ECHO); 994 } 995 996 static inline bool mptcp_pm_should_rm_signal(struct mptcp_sock *msk) 997 { 998 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_RM_ADDR_SIGNAL); 999 } 1000 1001 static inline bool mptcp_pm_is_userspace(const struct mptcp_sock *msk) 1002 { 1003 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_USERSPACE; 1004 } 1005 1006 static inline bool mptcp_pm_is_kernel(const struct mptcp_sock *msk) 1007 { 1008 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_KERNEL; 1009 } 1010 1011 static inline unsigned int mptcp_add_addr_len(int family, bool echo, bool port) 1012 { 1013 u8 len = TCPOLEN_MPTCP_ADD_ADDR_BASE; 1014 1015 if (family == AF_INET6) 1016 len = TCPOLEN_MPTCP_ADD_ADDR6_BASE; 1017 if (!echo) 1018 len += MPTCPOPT_THMAC_LEN; 1019 /* account for 2 trailing 'nop' options */ 1020 if (port) 1021 len += TCPOLEN_MPTCP_PORT_LEN + TCPOLEN_MPTCP_PORT_ALIGN; 1022 1023 return len; 1024 } 1025 1026 static inline int mptcp_rm_addr_len(const struct mptcp_rm_list *rm_list) 1027 { 1028 if (rm_list->nr == 0 || rm_list->nr > MPTCP_RM_IDS_MAX) 1029 return -EINVAL; 1030 1031 return TCPOLEN_MPTCP_RM_ADDR_BASE + roundup(rm_list->nr - 1, 4) + 1; 1032 } 1033 1034 bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, const struct sk_buff *skb, 1035 unsigned int opt_size, unsigned int remaining, 1036 struct mptcp_addr_info *addr, bool *echo, 1037 bool *drop_other_suboptions); 1038 bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining, 1039 struct mptcp_rm_list *rm_list); 1040 int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc); 1041 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc); 1042 int mptcp_userspace_pm_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc); 1043 bool mptcp_pm_is_backup(struct mptcp_sock *msk, struct sock_common *skc); 1044 bool mptcp_pm_nl_is_backup(struct mptcp_sock *msk, struct mptcp_addr_info *skc); 1045 bool mptcp_userspace_pm_is_backup(struct mptcp_sock *msk, struct mptcp_addr_info *skc); 1046 1047 static inline u8 subflow_get_local_id(const struct mptcp_subflow_context *subflow) 1048 { 1049 int local_id = READ_ONCE(subflow->local_id); 1050 1051 if (local_id < 0) 1052 return 0; 1053 return local_id; 1054 } 1055 1056 void __init mptcp_pm_nl_init(void); 1057 void mptcp_pm_nl_work(struct mptcp_sock *msk); 1058 unsigned int mptcp_pm_get_add_addr_signal_max(const struct mptcp_sock *msk); 1059 unsigned int mptcp_pm_get_add_addr_accept_max(const struct mptcp_sock *msk); 1060 unsigned int mptcp_pm_get_subflows_max(const struct mptcp_sock *msk); 1061 unsigned int mptcp_pm_get_local_addr_max(const struct mptcp_sock *msk); 1062 1063 /* called under PM lock */ 1064 static inline void __mptcp_pm_close_subflow(struct mptcp_sock *msk) 1065 { 1066 if (--msk->pm.subflows < mptcp_pm_get_subflows_max(msk)) 1067 WRITE_ONCE(msk->pm.accept_subflow, true); 1068 } 1069 1070 static inline void mptcp_pm_close_subflow(struct mptcp_sock *msk) 1071 { 1072 spin_lock_bh(&msk->pm.lock); 1073 __mptcp_pm_close_subflow(msk); 1074 spin_unlock_bh(&msk->pm.lock); 1075 } 1076 1077 void mptcp_sockopt_sync(struct mptcp_sock *msk, struct sock *ssk); 1078 void mptcp_sockopt_sync_locked(struct mptcp_sock *msk, struct sock *ssk); 1079 1080 static inline struct mptcp_ext *mptcp_get_ext(const struct sk_buff *skb) 1081 { 1082 return (struct mptcp_ext *)skb_ext_find(skb, SKB_EXT_MPTCP); 1083 } 1084 1085 void mptcp_diag_subflow_init(struct tcp_ulp_ops *ops); 1086 1087 static inline bool __mptcp_check_fallback(const struct mptcp_sock *msk) 1088 { 1089 return test_bit(MPTCP_FALLBACK_DONE, &msk->flags); 1090 } 1091 1092 static inline bool mptcp_check_fallback(const struct sock *sk) 1093 { 1094 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 1095 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 1096 1097 return __mptcp_check_fallback(msk); 1098 } 1099 1100 static inline void __mptcp_do_fallback(struct mptcp_sock *msk) 1101 { 1102 if (test_bit(MPTCP_FALLBACK_DONE, &msk->flags)) { 1103 pr_debug("TCP fallback already done (msk=%p)\n", msk); 1104 return; 1105 } 1106 if (WARN_ON_ONCE(!READ_ONCE(msk->allow_infinite_fallback))) 1107 return; 1108 set_bit(MPTCP_FALLBACK_DONE, &msk->flags); 1109 } 1110 1111 static inline void mptcp_do_fallback(struct sock *ssk) 1112 { 1113 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 1114 struct sock *sk = subflow->conn; 1115 struct mptcp_sock *msk; 1116 1117 msk = mptcp_sk(sk); 1118 __mptcp_do_fallback(msk); 1119 if (READ_ONCE(msk->snd_data_fin_enable) && !(ssk->sk_shutdown & SEND_SHUTDOWN)) { 1120 gfp_t saved_allocation = ssk->sk_allocation; 1121 1122 /* we are in a atomic (BH) scope, override ssk default for data 1123 * fin allocation 1124 */ 1125 ssk->sk_allocation = GFP_ATOMIC; 1126 ssk->sk_shutdown |= SEND_SHUTDOWN; 1127 tcp_shutdown(ssk, SEND_SHUTDOWN); 1128 ssk->sk_allocation = saved_allocation; 1129 } 1130 } 1131 1132 #define pr_fallback(a) pr_debug("%s:fallback to TCP (msk=%p)\n", __func__, a) 1133 1134 static inline bool mptcp_check_infinite_map(struct sk_buff *skb) 1135 { 1136 struct mptcp_ext *mpext; 1137 1138 mpext = skb ? mptcp_get_ext(skb) : NULL; 1139 if (mpext && mpext->infinite_map) 1140 return true; 1141 1142 return false; 1143 } 1144 1145 static inline bool is_active_ssk(struct mptcp_subflow_context *subflow) 1146 { 1147 return (subflow->request_mptcp || subflow->request_join); 1148 } 1149 1150 static inline bool subflow_simultaneous_connect(struct sock *sk) 1151 { 1152 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 1153 1154 return (1 << sk->sk_state) & 1155 (TCPF_ESTABLISHED | TCPF_FIN_WAIT1 | TCPF_FIN_WAIT2 | TCPF_CLOSING) && 1156 is_active_ssk(subflow) && 1157 !subflow->conn_finished; 1158 } 1159 1160 #ifdef CONFIG_SYN_COOKIES 1161 void subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 1162 struct sk_buff *skb); 1163 bool mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 1164 struct sk_buff *skb); 1165 void __init mptcp_join_cookie_init(void); 1166 #else 1167 static inline void 1168 subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 1169 struct sk_buff *skb) {} 1170 static inline bool 1171 mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 1172 struct sk_buff *skb) 1173 { 1174 return false; 1175 } 1176 1177 static inline void mptcp_join_cookie_init(void) {} 1178 #endif 1179 1180 #endif /* __MPTCP_PROTOCOL_H */ 1181