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 #include <net/rstreason.h> 16 17 #define MPTCP_SUPPORTED_VERSION 1 18 19 /* MPTCP option bits */ 20 #define OPTION_MPTCP_MPC_SYN BIT(0) 21 #define OPTION_MPTCP_MPC_SYNACK BIT(1) 22 #define OPTION_MPTCP_MPC_ACK BIT(2) 23 #define OPTION_MPTCP_MPJ_SYN BIT(3) 24 #define OPTION_MPTCP_MPJ_SYNACK BIT(4) 25 #define OPTION_MPTCP_MPJ_ACK BIT(5) 26 #define OPTION_MPTCP_ADD_ADDR BIT(6) 27 #define OPTION_MPTCP_RM_ADDR BIT(7) 28 #define OPTION_MPTCP_FASTCLOSE BIT(8) 29 #define OPTION_MPTCP_PRIO BIT(9) 30 #define OPTION_MPTCP_RST BIT(10) 31 #define OPTION_MPTCP_DSS BIT(11) 32 #define OPTION_MPTCP_FAIL BIT(12) 33 34 #define OPTION_MPTCP_CSUMREQD BIT(13) 35 36 #define OPTIONS_MPTCP_MPC (OPTION_MPTCP_MPC_SYN | OPTION_MPTCP_MPC_SYNACK | \ 37 OPTION_MPTCP_MPC_ACK) 38 #define OPTIONS_MPTCP_MPJ (OPTION_MPTCP_MPJ_SYN | OPTION_MPTCP_MPJ_SYNACK | \ 39 OPTION_MPTCP_MPJ_ACK) 40 #define OPTIONS_MPTCP_DSS (OPTION_MPTCP_DSS | OPTION_MPTCP_CSUMREQD) 41 42 /* MPTCP option subtypes */ 43 #define MPTCPOPT_MP_CAPABLE 0 44 #define MPTCPOPT_MP_JOIN 1 45 #define MPTCPOPT_DSS 2 46 #define MPTCPOPT_ADD_ADDR 3 47 #define MPTCPOPT_RM_ADDR 4 48 #define MPTCPOPT_MP_PRIO 5 49 #define MPTCPOPT_MP_FAIL 6 50 #define MPTCPOPT_MP_FASTCLOSE 7 51 #define MPTCPOPT_RST 8 52 53 /* MPTCP suboption lengths */ 54 #define TCPOLEN_MPTCP_MPC_SYN 4 55 #define TCPOLEN_MPTCP_MPC_SYNACK 12 56 #define TCPOLEN_MPTCP_MPC_ACK 20 57 #define TCPOLEN_MPTCP_MPC_ACK_DATA 22 58 #define TCPOLEN_MPTCP_MPJ_SYN 12 59 #define TCPOLEN_MPTCP_MPJ_SYNACK 16 60 #define TCPOLEN_MPTCP_MPJ_ACK 24 61 #define TCPOLEN_MPTCP_DSS_BASE 4 62 #define TCPOLEN_MPTCP_DSS_ACK32 4 63 #define TCPOLEN_MPTCP_DSS_ACK64 8 64 #define TCPOLEN_MPTCP_DSS_MAP32 10 65 #define TCPOLEN_MPTCP_DSS_MAP64 14 66 #define TCPOLEN_MPTCP_DSS_CHECKSUM 2 67 #define TCPOLEN_MPTCP_ADD_ADDR 16 68 #define TCPOLEN_MPTCP_ADD_ADDR_PORT 18 69 #define TCPOLEN_MPTCP_ADD_ADDR_BASE 8 70 #define TCPOLEN_MPTCP_ADD_ADDR_BASE_PORT 10 71 #define TCPOLEN_MPTCP_ADD_ADDR6 28 72 #define TCPOLEN_MPTCP_ADD_ADDR6_PORT 30 73 #define TCPOLEN_MPTCP_ADD_ADDR6_BASE 20 74 #define TCPOLEN_MPTCP_ADD_ADDR6_BASE_PORT 22 75 #define TCPOLEN_MPTCP_PORT_LEN 2 76 #define TCPOLEN_MPTCP_PORT_ALIGN 2 77 #define TCPOLEN_MPTCP_RM_ADDR_BASE 3 78 #define TCPOLEN_MPTCP_PRIO 3 79 #define TCPOLEN_MPTCP_PRIO_ALIGN 4 80 #define TCPOLEN_MPTCP_FASTCLOSE 12 81 #define TCPOLEN_MPTCP_RST 4 82 #define TCPOLEN_MPTCP_FAIL 12 83 84 #define TCPOLEN_MPTCP_MPC_ACK_DATA_CSUM (TCPOLEN_MPTCP_DSS_CHECKSUM + TCPOLEN_MPTCP_MPC_ACK_DATA) 85 86 /* MPTCP MP_JOIN flags */ 87 #define MPTCPOPT_BACKUP BIT(0) 88 #define MPTCPOPT_THMAC_LEN 8 89 90 /* MPTCP MP_CAPABLE flags */ 91 #define MPTCP_VERSION_MASK (0x0F) 92 #define MPTCP_CAP_CHECKSUM_REQD BIT(7) 93 #define MPTCP_CAP_EXTENSIBILITY BIT(6) 94 #define MPTCP_CAP_DENY_JOIN_ID0 BIT(5) 95 #define MPTCP_CAP_HMAC_SHA256 BIT(0) 96 #define MPTCP_CAP_FLAG_MASK (0x1F) 97 98 /* MPTCP DSS flags */ 99 #define MPTCP_DSS_DATA_FIN BIT(4) 100 #define MPTCP_DSS_DSN64 BIT(3) 101 #define MPTCP_DSS_HAS_MAP BIT(2) 102 #define MPTCP_DSS_ACK64 BIT(1) 103 #define MPTCP_DSS_HAS_ACK BIT(0) 104 #define MPTCP_DSS_FLAG_MASK (0x1F) 105 106 /* MPTCP ADD_ADDR flags */ 107 #define MPTCP_ADDR_ECHO BIT(0) 108 109 /* MPTCP MP_PRIO flags */ 110 #define MPTCP_PRIO_BKUP BIT(0) 111 112 /* MPTCP TCPRST flags */ 113 #define MPTCP_RST_TRANSIENT BIT(0) 114 115 /* MPTCP socket atomic flags */ 116 #define MPTCP_WORK_RTX 1 117 #define MPTCP_FALLBACK_DONE 2 118 #define MPTCP_WORK_CLOSE_SUBFLOW 3 119 120 /* MPTCP socket release cb flags */ 121 #define MPTCP_PUSH_PENDING 1 122 #define MPTCP_CLEAN_UNA 2 123 #define MPTCP_ERROR_REPORT 3 124 #define MPTCP_RETRANSMIT 4 125 #define MPTCP_FLUSH_JOIN_LIST 5 126 #define MPTCP_SYNC_STATE 6 127 #define MPTCP_SYNC_SNDBUF 7 128 129 struct mptcp_skb_cb { 130 u64 map_seq; 131 u64 end_seq; 132 u32 offset; 133 u8 has_rxtstamp; 134 u8 cant_coalesce; 135 }; 136 137 #define MPTCP_SKB_CB(__skb) ((struct mptcp_skb_cb *)&((__skb)->cb[0])) 138 139 static inline bool before64(__u64 seq1, __u64 seq2) 140 { 141 return (__s64)(seq1 - seq2) < 0; 142 } 143 144 #define after64(seq2, seq1) before64(seq1, seq2) 145 146 struct mptcp_options_received { 147 u64 sndr_key; 148 u64 rcvr_key; 149 u64 data_ack; 150 u64 data_seq; 151 u32 subflow_seq; 152 u16 data_len; 153 __sum16 csum; 154 struct_group(status, 155 u16 suboptions; 156 u16 use_map:1, 157 dsn64:1, 158 data_fin:1, 159 use_ack:1, 160 ack64:1, 161 mpc_map:1, 162 reset_reason:4, 163 reset_transient:1, 164 echo:1, 165 backup:1, 166 deny_join_id0:1, 167 __unused:2; 168 ); 169 u8 join_id; 170 u32 token; 171 u32 nonce; 172 u64 thmac; 173 u8 hmac[MPTCPOPT_HMAC_LEN]; 174 struct mptcp_addr_info addr; 175 struct mptcp_rm_list rm_list; 176 u64 ahmac; 177 u64 fail_seq; 178 }; 179 180 static inline __be32 mptcp_option(u8 subopt, u8 len, u8 nib, u8 field) 181 { 182 return htonl((TCPOPT_MPTCP << 24) | (len << 16) | (subopt << 12) | 183 ((nib & 0xF) << 8) | field); 184 } 185 186 enum mptcp_pm_status { 187 MPTCP_PM_ADD_ADDR_RECEIVED, 188 MPTCP_PM_ADD_ADDR_SEND_ACK, 189 MPTCP_PM_RM_ADDR_RECEIVED, 190 MPTCP_PM_ESTABLISHED, 191 MPTCP_PM_SUBFLOW_ESTABLISHED, 192 MPTCP_PM_ALREADY_ESTABLISHED, /* persistent status, set after ESTABLISHED event */ 193 MPTCP_PM_MPC_ENDPOINT_ACCOUNTED, /* persistent status, set after MPC local address is 194 * accounted int id_avail_bitmap 195 */ 196 MPTCP_PM_DESTROYING, /* To fence out PM list allocs */ 197 }; 198 199 enum mptcp_pm_type { 200 MPTCP_PM_TYPE_KERNEL = 0, 201 MPTCP_PM_TYPE_USERSPACE, 202 203 __MPTCP_PM_TYPE_NR, 204 __MPTCP_PM_TYPE_MAX = __MPTCP_PM_TYPE_NR - 1, 205 }; 206 207 /* Status bits below MPTCP_PM_ALREADY_ESTABLISHED need pm worker actions */ 208 #define MPTCP_PM_WORK_MASK ((1 << MPTCP_PM_ALREADY_ESTABLISHED) - 1) 209 210 enum mptcp_addr_signal_status { 211 MPTCP_ADD_ADDR_SIGNAL, 212 MPTCP_ADD_ADDR_ECHO, 213 MPTCP_RM_ADDR_SIGNAL, 214 }; 215 216 /* max value of mptcp_addr_info.id */ 217 #define MPTCP_PM_MAX_ADDR_ID U8_MAX 218 219 struct mptcp_pm_data { 220 struct mptcp_addr_info local; 221 struct mptcp_addr_info remote; 222 struct list_head anno_list; 223 struct list_head userspace_pm_local_addr_list; 224 225 spinlock_t lock; /*protects the whole PM data */ 226 227 struct_group(reset, 228 229 u8 addr_signal; 230 bool server_side; 231 bool work_pending; 232 bool accept_addr; 233 bool accept_subflow; 234 bool remote_deny_join_id0; 235 u8 add_addr_signaled; 236 u8 add_addr_accepted; 237 u8 local_addr_used; 238 u8 pm_type; 239 u8 extra_subflows; 240 u8 status; 241 242 ); 243 244 DECLARE_BITMAP(id_avail_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); 245 struct mptcp_rm_list rm_list_tx; 246 struct mptcp_rm_list rm_list_rx; 247 }; 248 249 struct mptcp_pm_local { 250 struct mptcp_addr_info addr; 251 u32 flags; 252 int ifindex; 253 }; 254 255 struct mptcp_pm_addr_entry { 256 struct list_head list; 257 struct mptcp_addr_info addr; 258 u32 flags; 259 int ifindex; 260 struct socket *lsk; 261 }; 262 263 struct mptcp_data_frag { 264 struct list_head list; 265 u64 data_seq; 266 u16 data_len; 267 u16 offset; 268 u8 overhead; 269 u8 eor; /* currently using 1 bit */ 270 u16 already_sent; 271 struct page *page; 272 }; 273 274 /* Arbitrary compromise between as low as possible to react timely to subflow 275 * close event and as big as possible to avoid being fouled by biased large 276 * samples due to peer sending data on a different subflow WRT to the incoming 277 * ack. 278 */ 279 #define MPTCP_RTT_SAMPLES 5 280 281 /* MPTCP connection sock */ 282 struct mptcp_sock { 283 /* inet_connection_sock must be the first member */ 284 struct inet_connection_sock sk; 285 u64 local_key; /* protected by the first subflow socket lock 286 * lockless access read 287 */ 288 u64 remote_key; /* same as above */ 289 u64 write_seq; 290 u64 bytes_sent; 291 u64 snd_nxt; 292 u64 bytes_received; 293 u64 ack_seq; 294 atomic64_t rcv_wnd_sent; 295 u64 rcv_data_fin_seq; 296 u64 bytes_retrans; 297 u64 bytes_consumed; 298 int snd_burst; 299 int old_wspace; 300 u64 recovery_snd_nxt; /* in recovery mode accept up to this seq; 301 * recovery related fields are under data_lock 302 * protection 303 */ 304 u64 bytes_acked; 305 u64 snd_una; 306 u64 wnd_end; 307 u32 last_data_sent; 308 u32 last_data_recv; 309 u32 last_ack_recv; 310 unsigned long timer_ival; 311 u32 token; 312 unsigned long flags; 313 unsigned long cb_flags; 314 bool recovery; /* closing subflow write queue reinjected */ 315 bool can_ack; 316 bool fully_established; 317 bool rcv_data_fin; 318 bool snd_data_fin_enable; 319 bool rcv_fastclose; 320 bool use_64bit_ack; /* Set when we received a 64-bit DSN */ 321 bool csum_enabled; 322 bool allow_infinite_fallback; 323 u8 pending_state; /* A subflow asked to set this sk_state, 324 * protected by the msk data lock 325 */ 326 u8 mpc_endpoint_id; 327 u8 recvmsg_inq:1, 328 cork:1, 329 nodelay:1, 330 fastopening:1, 331 in_accept_queue:1, 332 free_first:1, 333 rcvspace_init:1, 334 fastclosing:1; 335 u32 notsent_lowat; 336 int keepalive_cnt; 337 int keepalive_idle; 338 int keepalive_intvl; 339 int maxseg; 340 struct work_struct work; 341 struct sk_buff *ooo_last_skb; 342 struct rb_root out_of_order_queue; 343 struct list_head conn_list; 344 struct list_head rtx_queue; 345 struct mptcp_data_frag *first_pending; 346 struct list_head join_list; 347 struct sock *first; /* The mptcp ops can safely dereference, using suitable 348 * ONCE annotation, the subflow outside the socket 349 * lock as such sock is freed after close(). 350 */ 351 struct mptcp_pm_data pm; 352 struct mptcp_sched_ops *sched; 353 354 /* Most recent rtt_us observed by in use incoming subflows. */ 355 struct { 356 u32 samples[MPTCP_RTT_SAMPLES]; 357 u32 next_sample; 358 } rcv_rtt_est; 359 360 struct { 361 int space; /* bytes copied in last measurement window */ 362 int copied; /* bytes copied in this measurement window */ 363 u64 time; /* start time of measurement window */ 364 } rcvq_space; 365 u8 scaling_ratio; 366 bool allow_subflows; 367 368 u32 subflow_id; 369 u32 setsockopt_seq; 370 char ca_name[TCP_CA_NAME_MAX]; 371 372 spinlock_t fallback_lock; /* protects fallback, 373 * allow_infinite_fallback and 374 * allow_join 375 */ 376 377 struct list_head backlog_list; /* protected by the data lock */ 378 u32 backlog_len; 379 u32 backlog_unaccounted; 380 }; 381 382 #define mptcp_data_lock(sk) spin_lock_bh(&(sk)->sk_lock.slock) 383 #define mptcp_data_unlock(sk) spin_unlock_bh(&(sk)->sk_lock.slock) 384 385 #define mptcp_for_each_subflow(__msk, __subflow) \ 386 list_for_each_entry(__subflow, &((__msk)->conn_list), node) 387 #define mptcp_for_each_subflow_safe(__msk, __subflow, __tmp) \ 388 list_for_each_entry_safe(__subflow, __tmp, &((__msk)->conn_list), node) 389 #define mptcp_next_subflow(__msk, __subflow) \ 390 list_next_entry_circular(__subflow, &((__msk)->conn_list), node) 391 392 extern struct genl_family mptcp_genl_family; 393 394 static inline void msk_owned_by_me(const struct mptcp_sock *msk) 395 { 396 sock_owned_by_me((const struct sock *)msk); 397 } 398 399 #ifdef CONFIG_DEBUG_NET 400 /* MPTCP-specific: we might (indirectly) call this helper with the wrong sk */ 401 #undef tcp_sk 402 #define tcp_sk(ptr) ({ \ 403 typeof(ptr) _ptr = (ptr); \ 404 WARN_ON(_ptr->sk_protocol != IPPROTO_TCP); \ 405 container_of_const(_ptr, struct tcp_sock, inet_conn.icsk_inet.sk); \ 406 }) 407 #define mptcp_sk(ptr) ({ \ 408 typeof(ptr) _ptr = (ptr); \ 409 WARN_ON(_ptr->sk_protocol != IPPROTO_MPTCP); \ 410 container_of_const(_ptr, struct mptcp_sock, sk.icsk_inet.sk); \ 411 }) 412 413 #else /* !CONFIG_DEBUG_NET */ 414 #define mptcp_sk(ptr) container_of_const(ptr, struct mptcp_sock, sk.icsk_inet.sk) 415 #endif 416 417 static inline int mptcp_win_from_space(const struct sock *sk, int space) 418 { 419 return __tcp_win_from_space(mptcp_sk(sk)->scaling_ratio, space); 420 } 421 422 static inline int mptcp_space_from_win(const struct sock *sk, int win) 423 { 424 return __tcp_space_from_win(mptcp_sk(sk)->scaling_ratio, win); 425 } 426 427 static inline int __mptcp_space(const struct sock *sk) 428 { 429 return mptcp_win_from_space(sk, READ_ONCE(sk->sk_rcvbuf) - 430 READ_ONCE(mptcp_sk(sk)->backlog_len) - 431 sk_rmem_alloc_get(sk)); 432 } 433 434 static inline struct mptcp_data_frag *mptcp_send_head(const struct sock *sk) 435 { 436 const struct mptcp_sock *msk = mptcp_sk(sk); 437 438 return msk->first_pending; 439 } 440 441 static inline void mptcp_init_rtt_est(struct mptcp_sock *msk) 442 { 443 int i; 444 445 for (i = 0; i < MPTCP_RTT_SAMPLES; ++i) 446 msk->rcv_rtt_est.samples[i] = U32_MAX; 447 msk->rcv_rtt_est.next_sample = 0; 448 msk->scaling_ratio = TCP_DEFAULT_SCALING_RATIO; 449 } 450 451 static inline u32 mptcp_rtt_us_est(const struct mptcp_sock *msk) 452 { 453 u32 rtt_us = READ_ONCE(msk->rcv_rtt_est.samples[0]); 454 int i; 455 456 /* Lockless access of collected samples. */ 457 for (i = 1; i < MPTCP_RTT_SAMPLES; ++i) 458 rtt_us = min(rtt_us, READ_ONCE(msk->rcv_rtt_est.samples[i])); 459 return rtt_us; 460 } 461 462 static inline struct mptcp_data_frag *mptcp_send_next(struct sock *sk) 463 { 464 struct mptcp_sock *msk = mptcp_sk(sk); 465 struct mptcp_data_frag *cur; 466 467 cur = msk->first_pending; 468 return list_is_last(&cur->list, &msk->rtx_queue) ? NULL : 469 list_next_entry(cur, list); 470 } 471 472 static inline struct mptcp_data_frag *mptcp_pending_tail(const struct sock *sk) 473 { 474 const struct mptcp_sock *msk = mptcp_sk(sk); 475 476 if (!msk->first_pending) 477 return NULL; 478 479 if (WARN_ON_ONCE(list_empty(&msk->rtx_queue))) 480 return NULL; 481 482 return list_last_entry(&msk->rtx_queue, struct mptcp_data_frag, list); 483 } 484 485 static inline struct mptcp_data_frag *mptcp_rtx_head(struct sock *sk) 486 { 487 struct mptcp_sock *msk = mptcp_sk(sk); 488 489 if (msk->snd_una == msk->snd_nxt) 490 return NULL; 491 492 return list_first_entry_or_null(&msk->rtx_queue, struct mptcp_data_frag, list); 493 } 494 495 struct csum_pseudo_header { 496 __be64 data_seq; 497 __be32 subflow_seq; 498 __be16 data_len; 499 __sum16 csum; 500 }; 501 502 struct mptcp_subflow_request_sock { 503 struct tcp_request_sock sk; 504 u16 mp_capable : 1, 505 mp_join : 1, 506 backup : 1, 507 request_bkup : 1, 508 csum_reqd : 1, 509 allow_join_id0 : 1; 510 u8 local_id; 511 u8 remote_id; 512 u64 local_key; 513 u64 idsn; 514 u32 token; 515 u32 ssn_offset; 516 u64 thmac; 517 u32 local_nonce; 518 u32 remote_nonce; 519 struct mptcp_sock *msk; 520 struct hlist_nulls_node token_node; 521 }; 522 523 static inline struct mptcp_subflow_request_sock * 524 mptcp_subflow_rsk(const struct request_sock *rsk) 525 { 526 return (struct mptcp_subflow_request_sock *)rsk; 527 } 528 529 struct mptcp_delegated_action { 530 struct napi_struct napi; 531 local_lock_t bh_lock; 532 struct list_head head; 533 }; 534 535 DECLARE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions); 536 537 #define MPTCP_DELEGATE_SCHEDULED 0 538 #define MPTCP_DELEGATE_SEND 1 539 #define MPTCP_DELEGATE_ACK 2 540 #define MPTCP_DELEGATE_SNDBUF 3 541 542 #define MPTCP_DELEGATE_ACTIONS_MASK (~BIT(MPTCP_DELEGATE_SCHEDULED)) 543 /* MPTCP subflow context */ 544 struct mptcp_subflow_context { 545 struct list_head node;/* conn_list of subflows */ 546 547 struct_group(reset, 548 549 unsigned long avg_pacing_rate; /* protected by msk socket lock */ 550 u64 local_key; 551 u64 remote_key; 552 u64 idsn; 553 u64 map_seq; 554 u64 rcv_wnd_sent; 555 u32 snd_isn; 556 u32 token; 557 u32 rel_write_seq; 558 u32 map_subflow_seq; 559 u32 ssn_offset; 560 u32 map_data_len; 561 __wsum map_data_csum; 562 u32 map_csum_len; 563 u32 prev_rtt_seq; 564 u32 request_mptcp : 1, /* send MP_CAPABLE */ 565 request_join : 1, /* send MP_JOIN */ 566 request_bkup : 1, 567 mp_capable : 1, /* remote is MPTCP capable */ 568 mp_join : 1, /* remote is JOINing */ 569 pm_notified : 1, /* PM hook called for established status */ 570 conn_finished : 1, 571 map_valid : 1, 572 map_csum_reqd : 1, 573 map_data_fin : 1, 574 mpc_map : 1, 575 backup : 1, 576 send_mp_prio : 1, 577 send_mp_fail : 1, 578 send_fastclose : 1, 579 send_infinite_map : 1, 580 remote_key_valid : 1, /* received the peer key from */ 581 disposable : 1, /* ctx can be free at ulp release time */ 582 closing : 1, /* must not pass rx data to msk anymore */ 583 valid_csum_seen : 1, /* at least one csum validated */ 584 is_mptfo : 1, /* subflow is doing TFO */ 585 close_event_done : 1, /* has done the post-closed part */ 586 mpc_drop : 1, /* the MPC option has been dropped in a rtx */ 587 __unused : 9; 588 bool data_avail; 589 bool scheduled; 590 bool pm_listener; /* a listener managed by the kernel PM? */ 591 bool fully_established; /* path validated */ 592 u32 lent_mem_frag; 593 u32 remote_nonce; 594 u64 thmac; 595 u32 local_nonce; 596 u32 remote_token; 597 union { 598 u8 hmac[MPTCPOPT_HMAC_LEN]; /* MPJ subflow only */ 599 u64 iasn; /* initial ack sequence number, MPC subflows only */ 600 }; 601 s16 local_id; /* if negative not initialized yet */ 602 u8 remote_id; 603 u8 reset_seen:1; 604 u8 reset_transient:1; 605 u8 reset_reason:4; 606 u8 stale_count; /* Protected by the msk socket lock */ 607 u8 stale; /* Protected by the msk socket lock, 608 * if set the subflow is unable to snd/rcv 609 * data, the schedule should skip it 610 */ 611 612 u32 subflow_id; 613 614 long delegated_status; 615 unsigned long fail_tout; 616 617 ); 618 619 struct list_head delegated_node; /* link into delegated_action, protected by local BH */ 620 621 u32 setsockopt_seq; 622 u32 stale_rcv_tstamp; 623 int cached_sndbuf; /* sndbuf size when last synced with the msk sndbuf, 624 * protected by the msk socket lock 625 */ 626 627 struct sock *tcp_sock; /* tcp sk backpointer */ 628 struct sock *conn; /* parent mptcp_sock */ 629 const struct inet_connection_sock_af_ops *icsk_af_ops; 630 void (*tcp_state_change)(struct sock *sk); 631 void (*tcp_error_report)(struct sock *sk); 632 633 struct rcu_head rcu; 634 }; 635 636 static inline struct mptcp_subflow_context * 637 mptcp_subflow_ctx(const struct sock *sk) 638 { 639 const struct inet_connection_sock *icsk = inet_csk(sk); 640 641 /* Use RCU on icsk_ulp_data only for sock diag code */ 642 return (__force struct mptcp_subflow_context *)icsk->icsk_ulp_data; 643 } 644 645 static inline struct sock * 646 mptcp_subflow_tcp_sock(const struct mptcp_subflow_context *subflow) 647 { 648 return subflow->tcp_sock; 649 } 650 651 static inline void 652 mptcp_subflow_ctx_reset(struct mptcp_subflow_context *subflow) 653 { 654 memset(&subflow->reset, 0, sizeof(subflow->reset)); 655 subflow->request_mptcp = 1; 656 WRITE_ONCE(subflow->local_id, -1); 657 } 658 659 /* Convert reset reasons in MPTCP to enum sk_rst_reason type */ 660 static inline enum sk_rst_reason 661 sk_rst_convert_mptcp_reason(u32 reason) 662 { 663 switch (reason) { 664 case MPTCP_RST_EUNSPEC: 665 return SK_RST_REASON_MPTCP_RST_EUNSPEC; 666 case MPTCP_RST_EMPTCP: 667 return SK_RST_REASON_MPTCP_RST_EMPTCP; 668 case MPTCP_RST_ERESOURCE: 669 return SK_RST_REASON_MPTCP_RST_ERESOURCE; 670 case MPTCP_RST_EPROHIBIT: 671 return SK_RST_REASON_MPTCP_RST_EPROHIBIT; 672 case MPTCP_RST_EWQ2BIG: 673 return SK_RST_REASON_MPTCP_RST_EWQ2BIG; 674 case MPTCP_RST_EBADPERF: 675 return SK_RST_REASON_MPTCP_RST_EBADPERF; 676 case MPTCP_RST_EMIDDLEBOX: 677 return SK_RST_REASON_MPTCP_RST_EMIDDLEBOX; 678 default: 679 /* It should not happen, or else errors may occur 680 * in MPTCP layer 681 */ 682 return SK_RST_REASON_ERROR; 683 } 684 } 685 686 static inline void 687 mptcp_send_active_reset_reason(struct sock *sk) 688 { 689 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 690 enum sk_rst_reason reason; 691 692 reason = sk_rst_convert_mptcp_reason(subflow->reset_reason); 693 tcp_send_active_reset(sk, GFP_ATOMIC, reason); 694 } 695 696 /* Made the fwd mem carried by the given skb available to the msk, 697 * To be paired with a previous mptcp_subflow_lend_fwdmem() before freeing 698 * the skb or setting the skb ownership. 699 */ 700 static inline void mptcp_borrow_fwdmem(struct sock *sk, struct sk_buff *skb) 701 { 702 struct sock *ssk = skb->sk; 703 704 /* The subflow just lend the skb fwd memory; if the subflow meanwhile 705 * closed, mptcp_close_ssk() already released the ssk rcv memory. 706 */ 707 DEBUG_NET_WARN_ON_ONCE(skb->destructor); 708 sk_forward_alloc_add(sk, skb->truesize); 709 if (!ssk) 710 return; 711 712 atomic_sub(skb->truesize, &ssk->sk_rmem_alloc); 713 skb->sk = NULL; 714 } 715 716 static inline void 717 __mptcp_subflow_lend_fwdmem(struct mptcp_subflow_context *subflow, int size) 718 { 719 int frag = (subflow->lent_mem_frag + size) & (PAGE_SIZE - 1); 720 721 subflow->lent_mem_frag = frag; 722 } 723 724 static inline void 725 mptcp_subflow_lend_fwdmem(struct mptcp_subflow_context *subflow, 726 struct sk_buff *skb) 727 { 728 __mptcp_subflow_lend_fwdmem(subflow, skb->truesize); 729 skb->destructor = NULL; 730 } 731 732 static inline u64 733 mptcp_subflow_get_map_offset(const struct mptcp_subflow_context *subflow) 734 { 735 return tcp_sk(mptcp_subflow_tcp_sock(subflow))->copied_seq - 736 subflow->ssn_offset - 737 subflow->map_subflow_seq; 738 } 739 740 static inline u64 741 mptcp_subflow_get_mapped_dsn(const struct mptcp_subflow_context *subflow) 742 { 743 return subflow->map_seq + mptcp_subflow_get_map_offset(subflow); 744 } 745 746 void mptcp_subflow_process_delegated(struct sock *ssk, long actions); 747 748 static inline void mptcp_subflow_delegate(struct mptcp_subflow_context *subflow, int action) 749 { 750 long old, set_bits = BIT(MPTCP_DELEGATE_SCHEDULED) | BIT(action); 751 struct mptcp_delegated_action *delegated; 752 bool schedule; 753 754 /* the caller held the subflow bh socket lock */ 755 lockdep_assert_in_softirq(); 756 757 /* The implied barrier pairs with tcp_release_cb_override() 758 * mptcp_napi_poll(), and ensures the below list check sees list 759 * updates done prior to delegated status bits changes 760 */ 761 old = set_mask_bits(&subflow->delegated_status, 0, set_bits); 762 if (!(old & BIT(MPTCP_DELEGATE_SCHEDULED))) { 763 if (WARN_ON_ONCE(!list_empty(&subflow->delegated_node))) 764 return; 765 766 local_lock_nested_bh(&mptcp_delegated_actions.bh_lock); 767 delegated = this_cpu_ptr(&mptcp_delegated_actions); 768 schedule = list_empty(&delegated->head); 769 list_add_tail(&subflow->delegated_node, &delegated->head); 770 local_unlock_nested_bh(&mptcp_delegated_actions.bh_lock); 771 sock_hold(mptcp_subflow_tcp_sock(subflow)); 772 if (schedule) 773 napi_schedule(&delegated->napi); 774 } 775 } 776 777 static inline struct mptcp_subflow_context * 778 mptcp_subflow_delegated_next(struct mptcp_delegated_action *delegated) 779 { 780 struct mptcp_subflow_context *ret; 781 782 local_lock_nested_bh(&mptcp_delegated_actions.bh_lock); 783 if (list_empty(&delegated->head)) { 784 local_unlock_nested_bh(&mptcp_delegated_actions.bh_lock); 785 return NULL; 786 } 787 788 ret = list_first_entry(&delegated->head, struct mptcp_subflow_context, delegated_node); 789 list_del_init(&ret->delegated_node); 790 local_unlock_nested_bh(&mptcp_delegated_actions.bh_lock); 791 return ret; 792 } 793 794 void __mptcp_inherit_memcg(struct sock *sk, struct sock *ssk, gfp_t gfp); 795 void __mptcp_inherit_cgrp_data(struct sock *sk, struct sock *ssk); 796 797 int mptcp_is_enabled(const struct net *net); 798 unsigned int mptcp_get_add_addr_timeout(const struct net *net); 799 int mptcp_is_checksum_enabled(const struct net *net); 800 int mptcp_allow_join_id0(const struct net *net); 801 unsigned int mptcp_stale_loss_cnt(const struct net *net); 802 unsigned int mptcp_close_timeout(const struct sock *sk); 803 int mptcp_get_pm_type(const struct net *net); 804 const char *mptcp_get_path_manager(const struct net *net); 805 const char *mptcp_get_scheduler(const struct net *net); 806 unsigned int mptcp_add_addr_v6_port_drop_ts(const struct net *net); 807 808 void mptcp_active_disable(struct sock *sk); 809 bool mptcp_active_should_disable(struct sock *ssk); 810 void mptcp_active_enable(struct sock *sk); 811 812 void mptcp_get_available_schedulers(char *buf, size_t maxlen); 813 void __mptcp_subflow_fully_established(struct mptcp_sock *msk, 814 struct mptcp_subflow_context *subflow, 815 const struct mptcp_options_received *mp_opt); 816 bool __mptcp_retransmit_pending_data(struct sock *sk); 817 void mptcp_check_and_set_pending(struct sock *sk); 818 void __mptcp_push_pending(struct sock *sk, unsigned int flags); 819 bool mptcp_subflow_data_available(struct sock *sk); 820 void __init mptcp_subflow_init(void); 821 void mptcp_subflow_shutdown(struct sock *sk, struct sock *ssk, int how); 822 void mptcp_close_ssk(struct sock *sk, struct sock *ssk, 823 struct mptcp_subflow_context *subflow); 824 void __mptcp_subflow_send_ack(struct sock *ssk); 825 void mptcp_subflow_reset(struct sock *ssk); 826 void mptcp_subflow_queue_clean(struct sock *sk, struct sock *ssk); 827 void mptcp_sock_graft(struct sock *sk, struct socket *parent); 828 struct sock *__mptcp_nmpc_sk(struct mptcp_sock *msk); 829 bool __mptcp_close(struct sock *sk, long timeout); 830 void mptcp_cancel_work(struct sock *sk); 831 void __mptcp_unaccepted_force_close(struct sock *sk); 832 void mptcp_set_state(struct sock *sk, int state); 833 834 bool mptcp_addresses_equal(const struct mptcp_addr_info *a, 835 const struct mptcp_addr_info *b, bool use_port); 836 void mptcp_local_address(const struct sock_common *skc, 837 struct mptcp_addr_info *addr); 838 void mptcp_remote_address(const struct sock_common *skc, 839 struct mptcp_addr_info *addr); 840 841 /* called with sk socket lock held */ 842 int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_pm_local *local, 843 const struct mptcp_addr_info *remote); 844 int mptcp_subflow_create_socket(struct sock *sk, unsigned short family, 845 struct socket **new_sock); 846 void mptcp_info2sockaddr(const struct mptcp_addr_info *info, 847 struct sockaddr_storage *addr, 848 unsigned short family); 849 struct mptcp_sched_ops *mptcp_sched_find(const char *name); 850 int mptcp_validate_scheduler(struct mptcp_sched_ops *sched); 851 int mptcp_register_scheduler(struct mptcp_sched_ops *sched); 852 void mptcp_unregister_scheduler(struct mptcp_sched_ops *sched); 853 void mptcp_sched_init(void); 854 int mptcp_init_sched(struct mptcp_sock *msk, 855 struct mptcp_sched_ops *sched); 856 void mptcp_release_sched(struct mptcp_sock *msk); 857 void mptcp_subflow_set_scheduled(struct mptcp_subflow_context *subflow, 858 bool scheduled); 859 struct sock *mptcp_subflow_get_send(struct mptcp_sock *msk); 860 struct sock *mptcp_subflow_get_retrans(struct mptcp_sock *msk); 861 int mptcp_sched_get_send(struct mptcp_sock *msk); 862 int mptcp_sched_get_retrans(struct mptcp_sock *msk); 863 864 static inline u64 mptcp_data_avail(const struct mptcp_sock *msk) 865 { 866 return READ_ONCE(msk->bytes_received) - READ_ONCE(msk->bytes_consumed); 867 } 868 869 static inline bool mptcp_epollin_ready(const struct sock *sk) 870 { 871 u64 data_avail = mptcp_data_avail(mptcp_sk(sk)); 872 873 if (!data_avail) 874 return false; 875 876 /* mptcp doesn't have to deal with small skbs in the receive queue, 877 * as it can always coalesce them 878 */ 879 return (data_avail >= sk->sk_rcvlowat) || 880 tcp_under_memory_pressure(sk); 881 } 882 883 int mptcp_set_rcvlowat(struct sock *sk, int val); 884 885 static inline bool __tcp_can_send(const struct sock *ssk) 886 { 887 /* only send if our side has not closed yet */ 888 return ((1 << inet_sk_state_load(ssk)) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)); 889 } 890 891 static inline bool __mptcp_subflow_active(struct mptcp_subflow_context *subflow) 892 { 893 /* can't send if JOIN hasn't completed yet (i.e. is usable for mptcp) */ 894 if (subflow->request_join && !READ_ONCE(subflow->fully_established)) 895 return false; 896 897 return __tcp_can_send(mptcp_subflow_tcp_sock(subflow)); 898 } 899 900 void mptcp_subflow_set_active(struct mptcp_subflow_context *subflow); 901 902 bool mptcp_subflow_active(struct mptcp_subflow_context *subflow); 903 904 void mptcp_subflow_drop_ctx(struct sock *ssk); 905 906 static inline void mptcp_subflow_tcp_fallback(struct sock *sk, 907 struct mptcp_subflow_context *ctx) 908 { 909 sk->sk_data_ready = sock_def_readable; 910 sk->sk_state_change = ctx->tcp_state_change; 911 sk->sk_write_space = sk_stream_write_space; 912 sk->sk_error_report = ctx->tcp_error_report; 913 914 inet_csk(sk)->icsk_af_ops = ctx->icsk_af_ops; 915 } 916 917 void __init mptcp_proto_init(void); 918 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 919 int __init mptcp_proto_v6_init(void); 920 void __init mptcp_subflow_v6_init(void); 921 #endif 922 923 struct sock *mptcp_sk_clone_init(const struct sock *sk, 924 const struct mptcp_options_received *mp_opt, 925 struct sock *ssk, 926 struct request_sock *req); 927 void mptcp_get_options(const struct sk_buff *skb, 928 struct mptcp_options_received *mp_opt); 929 930 void mptcp_finish_connect(struct sock *sk); 931 void __mptcp_sync_state(struct sock *sk, int state); 932 void mptcp_reset_tout_timer(struct mptcp_sock *msk, unsigned long fail_tout); 933 934 static inline void mptcp_stop_tout_timer(struct sock *sk) 935 { 936 if (!inet_csk(sk)->icsk_mtup.probe_timestamp) 937 return; 938 939 sk_stop_timer(sk, &inet_csk(sk)->mptcp_tout_timer); 940 inet_csk(sk)->icsk_mtup.probe_timestamp = 0; 941 } 942 943 static inline void mptcp_set_close_tout(struct sock *sk, unsigned long tout) 944 { 945 /* avoid 0 timestamp, as that means no close timeout */ 946 inet_csk(sk)->icsk_mtup.probe_timestamp = tout ? : 1; 947 } 948 949 static inline void mptcp_start_tout_timer(struct sock *sk) 950 { 951 mptcp_set_close_tout(sk, tcp_jiffies32); 952 mptcp_reset_tout_timer(mptcp_sk(sk), 0); 953 } 954 955 static inline bool mptcp_is_fully_established(struct sock *sk) 956 { 957 return inet_sk_state_load(sk) == TCP_ESTABLISHED && 958 READ_ONCE(mptcp_sk(sk)->fully_established); 959 } 960 961 static inline u64 mptcp_stamp(void) 962 { 963 return div_u64(tcp_clock_ns(), NSEC_PER_USEC); 964 } 965 966 void mptcp_data_ready(struct sock *sk, struct sock *ssk); 967 bool mptcp_finish_join(struct sock *sk); 968 bool mptcp_schedule_work(struct sock *sk); 969 int mptcp_setsockopt(struct sock *sk, int level, int optname, 970 sockptr_t optval, unsigned int optlen); 971 int mptcp_getsockopt(struct sock *sk, int level, int optname, 972 char __user *optval, int __user *option); 973 974 u64 __mptcp_expand_seq(u64 old_seq, u64 cur_seq); 975 static inline u64 mptcp_expand_seq(u64 old_seq, u64 cur_seq, bool use_64bit) 976 { 977 if (use_64bit) 978 return cur_seq; 979 980 return __mptcp_expand_seq(old_seq, cur_seq); 981 } 982 void __mptcp_check_push(struct sock *sk, struct sock *ssk); 983 void __mptcp_data_acked(struct sock *sk); 984 void __mptcp_error_report(struct sock *sk); 985 bool mptcp_update_rcv_data_fin(struct mptcp_sock *msk, u64 data_fin_seq, bool use_64bit); 986 static inline bool mptcp_data_fin_enabled(const struct mptcp_sock *msk) 987 { 988 return READ_ONCE(msk->snd_data_fin_enable) && 989 READ_ONCE(msk->write_seq) == READ_ONCE(msk->snd_nxt); 990 } 991 992 static inline u32 mptcp_notsent_lowat(const struct sock *sk) 993 { 994 struct net *net = sock_net(sk); 995 u32 val; 996 997 val = READ_ONCE(mptcp_sk(sk)->notsent_lowat); 998 return val ?: READ_ONCE(net->ipv4.sysctl_tcp_notsent_lowat); 999 } 1000 1001 static inline bool mptcp_stream_memory_free(const struct sock *sk, int wake) 1002 { 1003 const struct mptcp_sock *msk = mptcp_sk(sk); 1004 u32 notsent_bytes; 1005 1006 notsent_bytes = READ_ONCE(msk->write_seq) - READ_ONCE(msk->snd_nxt); 1007 return (notsent_bytes << wake) < mptcp_notsent_lowat(sk); 1008 } 1009 1010 static inline bool __mptcp_stream_is_writeable(const struct sock *sk, int wake) 1011 { 1012 return mptcp_stream_memory_free(sk, wake) && 1013 __sk_stream_is_writeable(sk, wake); 1014 } 1015 1016 static inline void mptcp_write_space(struct sock *sk) 1017 { 1018 /* pairs with memory barrier in mptcp_poll */ 1019 smp_mb(); 1020 if (mptcp_stream_memory_free(sk, 1)) 1021 INDIRECT_CALL_1(sk->sk_write_space, sk_stream_write_space, sk); 1022 } 1023 1024 static inline void __mptcp_sync_sndbuf(struct sock *sk) 1025 { 1026 struct mptcp_subflow_context *subflow; 1027 int ssk_sndbuf, new_sndbuf; 1028 1029 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) 1030 return; 1031 1032 new_sndbuf = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_wmem[0]); 1033 mptcp_for_each_subflow(mptcp_sk(sk), subflow) { 1034 ssk_sndbuf = READ_ONCE(mptcp_subflow_tcp_sock(subflow)->sk_sndbuf); 1035 1036 subflow->cached_sndbuf = ssk_sndbuf; 1037 new_sndbuf += ssk_sndbuf; 1038 } 1039 1040 /* the msk max wmem limit is <nr_subflows> * tcp wmem[2] */ 1041 WRITE_ONCE(sk->sk_sndbuf, new_sndbuf); 1042 mptcp_write_space(sk); 1043 } 1044 1045 /* The called held both the msk socket and the subflow socket locks, 1046 * possibly under BH 1047 */ 1048 static inline void __mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk) 1049 { 1050 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 1051 1052 if (READ_ONCE(ssk->sk_sndbuf) != subflow->cached_sndbuf) 1053 __mptcp_sync_sndbuf(sk); 1054 } 1055 1056 /* the caller held only the subflow socket lock, either in process or 1057 * BH context. Additionally this can be called under the msk data lock, 1058 * so we can't acquire such lock here: let the delegate action acquires 1059 * the needed locks in suitable order. 1060 */ 1061 static inline void mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk) 1062 { 1063 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 1064 1065 if (likely(READ_ONCE(ssk->sk_sndbuf) == subflow->cached_sndbuf)) 1066 return; 1067 1068 local_bh_disable(); 1069 mptcp_subflow_delegate(subflow, MPTCP_DELEGATE_SNDBUF); 1070 local_bh_enable(); 1071 } 1072 1073 #define MPTCP_TOKEN_MAX_RETRIES 4 1074 1075 void __init mptcp_token_init(void); 1076 static inline void mptcp_token_init_request(struct request_sock *req) 1077 { 1078 mptcp_subflow_rsk(req)->token_node.pprev = NULL; 1079 } 1080 1081 int mptcp_token_new_request(struct request_sock *req); 1082 void mptcp_token_destroy_request(struct request_sock *req); 1083 int mptcp_token_new_connect(struct sock *ssk); 1084 void mptcp_token_accept(struct mptcp_subflow_request_sock *r, 1085 struct mptcp_sock *msk); 1086 bool mptcp_token_exists(u32 token); 1087 struct mptcp_sock *mptcp_token_get_sock(struct net *net, u32 token); 1088 struct mptcp_sock *mptcp_token_iter_next(const struct net *net, long *s_slot, 1089 long *s_num); 1090 void mptcp_token_destroy(struct mptcp_sock *msk); 1091 1092 void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn); 1093 1094 void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u8 *msg, int len, void *hmac); 1095 __sum16 __mptcp_make_csum(u64 data_seq, u32 subflow_seq, u16 data_len, __wsum sum); 1096 1097 void __init mptcp_pm_init(void); 1098 void mptcp_pm_data_init(struct mptcp_sock *msk); 1099 void mptcp_pm_data_reset(struct mptcp_sock *msk); 1100 void mptcp_pm_destroy(struct mptcp_sock *msk); 1101 int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info, 1102 struct mptcp_addr_info *addr); 1103 int mptcp_pm_parse_entry(struct nlattr *attr, struct genl_info *info, 1104 bool require_family, 1105 struct mptcp_pm_addr_entry *entry); 1106 bool mptcp_pm_addr_families_match(const struct sock *sk, 1107 const struct mptcp_addr_info *loc, 1108 const struct mptcp_addr_info *rem); 1109 void mptcp_pm_chk_stale(const struct mptcp_sock *msk); 1110 void mptcp_pm_new_connection(struct mptcp_sock *msk, const struct sock *ssk, int server_side); 1111 void mptcp_pm_fully_established(struct mptcp_sock *msk, const struct sock *ssk); 1112 bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk); 1113 void mptcp_pm_connection_closed(struct mptcp_sock *msk); 1114 void mptcp_pm_subflow_established(struct mptcp_sock *msk); 1115 bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk); 1116 void mptcp_pm_subflow_check_next(struct mptcp_sock *msk, 1117 const struct mptcp_subflow_context *subflow); 1118 void mptcp_pm_add_addr_received(const struct sock *ssk, 1119 const struct mptcp_addr_info *addr); 1120 void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk, 1121 const struct mptcp_addr_info *addr); 1122 void mptcp_pm_send_ack(struct mptcp_sock *msk, 1123 struct mptcp_subflow_context *subflow, 1124 bool prio, bool backup); 1125 void mptcp_pm_addr_send_ack(struct mptcp_sock *msk); 1126 void mptcp_pm_nl_rm_addr(struct mptcp_sock *msk, u8 rm_id); 1127 void mptcp_pm_rm_subflow(struct mptcp_sock *msk, 1128 const struct mptcp_rm_list *rm_list); 1129 void mptcp_pm_rm_addr_received(struct mptcp_sock *msk, 1130 const struct mptcp_rm_list *rm_list); 1131 void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup); 1132 void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq); 1133 int mptcp_pm_mp_prio_send_ack(struct mptcp_sock *msk, 1134 struct mptcp_addr_info *addr, 1135 struct mptcp_addr_info *rem, 1136 u8 bkup); 1137 bool mptcp_pm_announced_alloc(struct mptcp_sock *msk, 1138 const struct mptcp_addr_info *addr); 1139 bool mptcp_pm_announced_remove(struct mptcp_sock *msk, 1140 const struct mptcp_addr_info *addr); 1141 bool mptcp_pm_announced_has_ssk(struct mptcp_sock *msk, const struct sock *ssk); 1142 bool mptcp_pm_has_subflow_saddr(const struct mptcp_sock *msk, 1143 const struct mptcp_addr_info *saddr); 1144 int mptcp_pm_nl_set_flags(struct mptcp_pm_addr_entry *local, 1145 struct genl_info *info); 1146 int mptcp_userspace_pm_set_flags(struct mptcp_pm_addr_entry *local, 1147 struct genl_info *info); 1148 int mptcp_pm_announce_addr(struct mptcp_sock *msk, 1149 const struct mptcp_addr_info *addr, 1150 bool echo); 1151 int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); 1152 void mptcp_pm_remove_addr_entry(struct mptcp_sock *msk, 1153 struct mptcp_pm_addr_entry *entry); 1154 1155 /* the default path manager, used in mptcp_pm_unregister */ 1156 extern struct mptcp_pm_ops mptcp_pm_kernel; 1157 1158 struct mptcp_pm_ops *mptcp_pm_find(const char *name); 1159 int mptcp_pm_register(struct mptcp_pm_ops *pm_ops); 1160 void mptcp_pm_unregister(struct mptcp_pm_ops *pm_ops); 1161 int mptcp_pm_validate(struct mptcp_pm_ops *pm_ops); 1162 void mptcp_pm_get_available(char *buf, size_t maxlen); 1163 1164 void mptcp_userspace_pm_free_local_addr_list(struct mptcp_sock *msk); 1165 1166 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk, 1167 const struct sock *ssk, gfp_t gfp); 1168 void mptcp_event_addr_announced(const struct sock *ssk, const struct mptcp_addr_info *info); 1169 void mptcp_event_addr_removed(const struct mptcp_sock *msk, u8 id); 1170 void mptcp_event_pm_listener(const struct sock *ssk, 1171 enum mptcp_event_type event); 1172 bool mptcp_userspace_pm_active(const struct mptcp_sock *msk); 1173 1174 void mptcp_fastopen_subflow_synack_set_params(struct mptcp_subflow_context *subflow, 1175 struct request_sock *req); 1176 int mptcp_pm_genl_fill_addr(struct sk_buff *msg, 1177 struct netlink_callback *cb, 1178 struct mptcp_pm_addr_entry *entry); 1179 1180 static inline bool mptcp_pm_should_add_signal(struct mptcp_sock *msk) 1181 { 1182 return READ_ONCE(msk->pm.addr_signal) & 1183 (BIT(MPTCP_ADD_ADDR_SIGNAL) | BIT(MPTCP_ADD_ADDR_ECHO)); 1184 } 1185 1186 static inline bool mptcp_pm_should_add_signal_addr(struct mptcp_sock *msk) 1187 { 1188 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_SIGNAL); 1189 } 1190 1191 static inline bool mptcp_pm_should_add_signal_echo(struct mptcp_sock *msk) 1192 { 1193 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_ECHO); 1194 } 1195 1196 static inline bool mptcp_pm_should_rm_signal(struct mptcp_sock *msk) 1197 { 1198 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_RM_ADDR_SIGNAL); 1199 } 1200 1201 static inline bool mptcp_pm_is_userspace(const struct mptcp_sock *msk) 1202 { 1203 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_USERSPACE; 1204 } 1205 1206 static inline bool mptcp_pm_is_kernel(const struct mptcp_sock *msk) 1207 { 1208 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_KERNEL; 1209 } 1210 1211 bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, int *size, int remaining, 1212 struct mptcp_addr_info *addr, bool *echo, 1213 bool *drop_ts); 1214 bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining, 1215 struct mptcp_rm_list *rm_list, int *len); 1216 int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc); 1217 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, 1218 struct mptcp_pm_addr_entry *skc); 1219 int mptcp_userspace_pm_get_local_id(struct mptcp_sock *msk, 1220 struct mptcp_pm_addr_entry *skc); 1221 bool mptcp_pm_is_backup(struct mptcp_sock *msk, struct sock_common *skc); 1222 bool mptcp_pm_nl_is_backup(struct mptcp_sock *msk, struct mptcp_addr_info *skc); 1223 bool mptcp_userspace_pm_is_backup(struct mptcp_sock *msk, struct mptcp_addr_info *skc); 1224 int mptcp_pm_nl_dump_addr(struct sk_buff *msg, 1225 struct netlink_callback *cb); 1226 int mptcp_userspace_pm_dump_addr(struct sk_buff *msg, 1227 struct netlink_callback *cb); 1228 int mptcp_pm_nl_get_addr(u8 id, struct mptcp_pm_addr_entry *addr, 1229 struct genl_info *info); 1230 int mptcp_userspace_pm_get_addr(u8 id, struct mptcp_pm_addr_entry *addr, 1231 struct genl_info *info); 1232 1233 static inline u8 subflow_get_local_id(const struct mptcp_subflow_context *subflow) 1234 { 1235 int local_id = READ_ONCE(subflow->local_id); 1236 1237 if (local_id < 0) 1238 return 0; 1239 return local_id; 1240 } 1241 1242 void __init mptcp_pm_kernel_register(void); 1243 void __init mptcp_pm_userspace_register(void); 1244 void __init mptcp_pm_nl_init(void); 1245 void mptcp_pm_worker(struct mptcp_sock *msk); 1246 void __mptcp_pm_kernel_worker(struct mptcp_sock *msk); 1247 u8 mptcp_pm_get_endp_signal_max(const struct mptcp_sock *msk); 1248 u8 mptcp_pm_get_endp_subflow_max(const struct mptcp_sock *msk); 1249 u8 mptcp_pm_get_endp_laminar_max(const struct mptcp_sock *msk); 1250 u8 mptcp_pm_get_endp_fullmesh_max(const struct mptcp_sock *msk); 1251 u8 mptcp_pm_get_limit_add_addr_accepted(const struct mptcp_sock *msk); 1252 u8 mptcp_pm_get_limit_extra_subflows(const struct mptcp_sock *msk); 1253 1254 /* called under PM lock */ 1255 static inline void __mptcp_pm_close_subflow(struct mptcp_sock *msk) 1256 { 1257 if (--msk->pm.extra_subflows < mptcp_pm_get_limit_extra_subflows(msk)) 1258 WRITE_ONCE(msk->pm.accept_subflow, true); 1259 } 1260 1261 static inline void mptcp_pm_close_subflow(struct mptcp_sock *msk) 1262 { 1263 spin_lock_bh(&msk->pm.lock); 1264 __mptcp_pm_close_subflow(msk); 1265 spin_unlock_bh(&msk->pm.lock); 1266 } 1267 1268 static inline bool mptcp_pm_add_addr_c_flag_case(struct mptcp_sock *msk) 1269 { 1270 return READ_ONCE(msk->pm.remote_deny_join_id0) && 1271 msk->pm.local_addr_used == 0 && 1272 mptcp_pm_get_limit_add_addr_accepted(msk) == 0 && 1273 msk->pm.extra_subflows < mptcp_pm_get_limit_extra_subflows(msk); 1274 } 1275 1276 void mptcp_sockopt_sync_locked(struct mptcp_sock *msk, struct sock *ssk); 1277 1278 static inline struct mptcp_ext *mptcp_get_ext(const struct sk_buff *skb) 1279 { 1280 return (struct mptcp_ext *)skb_ext_find(skb, SKB_EXT_MPTCP); 1281 } 1282 1283 void mptcp_diag_subflow_init(struct tcp_ulp_ops *ops); 1284 1285 static inline bool __mptcp_check_fallback(const struct mptcp_sock *msk) 1286 { 1287 return test_bit(MPTCP_FALLBACK_DONE, &msk->flags); 1288 } 1289 1290 static inline bool mptcp_check_fallback(const struct sock *sk) 1291 { 1292 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 1293 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 1294 1295 return __mptcp_check_fallback(msk); 1296 } 1297 1298 static inline bool __mptcp_has_initial_subflow(const struct mptcp_sock *msk) 1299 { 1300 struct sock *ssk = READ_ONCE(msk->first); 1301 1302 return ssk && ((1 << inet_sk_state_load(ssk)) & 1303 (TCPF_ESTABLISHED | TCPF_SYN_SENT | 1304 TCPF_SYN_RECV | TCPF_LISTEN)); 1305 } 1306 1307 bool __mptcp_try_fallback(struct mptcp_sock *msk, int fb_mib); 1308 1309 static inline bool mptcp_try_fallback(struct sock *ssk, int fb_mib) 1310 { 1311 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 1312 struct sock *sk = subflow->conn; 1313 struct mptcp_sock *msk; 1314 1315 msk = mptcp_sk(sk); 1316 if (!__mptcp_try_fallback(msk, fb_mib)) 1317 return false; 1318 if (READ_ONCE(msk->snd_data_fin_enable) && !(ssk->sk_shutdown & SEND_SHUTDOWN)) { 1319 gfp_t saved_allocation = ssk->sk_allocation; 1320 1321 /* we are in a atomic (BH) scope, override ssk default for data 1322 * fin allocation 1323 */ 1324 ssk->sk_allocation = GFP_ATOMIC; 1325 ssk->sk_shutdown |= SEND_SHUTDOWN; 1326 tcp_shutdown(ssk, SEND_SHUTDOWN); 1327 ssk->sk_allocation = saved_allocation; 1328 } 1329 return true; 1330 } 1331 1332 static inline void mptcp_early_fallback(struct mptcp_sock *msk, 1333 struct mptcp_subflow_context *subflow, 1334 int fb_mib) 1335 { 1336 subflow->request_mptcp = 0; 1337 WARN_ON_ONCE(!__mptcp_try_fallback(msk, fb_mib)); 1338 } 1339 1340 static inline bool mptcp_check_infinite_map(struct sk_buff *skb) 1341 { 1342 struct mptcp_ext *mpext; 1343 1344 mpext = skb ? mptcp_get_ext(skb) : NULL; 1345 if (mpext && mpext->infinite_map) 1346 return true; 1347 1348 return false; 1349 } 1350 1351 static inline bool is_active_ssk(struct mptcp_subflow_context *subflow) 1352 { 1353 return (subflow->request_mptcp || subflow->request_join); 1354 } 1355 1356 static inline bool subflow_simultaneous_connect(struct sock *sk) 1357 { 1358 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 1359 1360 /* Note that the sk state implies !subflow->conn_finished. */ 1361 return sk->sk_state == TCP_SYN_RECV && is_active_ssk(subflow); 1362 } 1363 1364 #ifdef CONFIG_SYN_COOKIES 1365 void subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 1366 struct sk_buff *skb); 1367 bool mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 1368 struct sk_buff *skb); 1369 void __init mptcp_join_cookie_init(void); 1370 #else 1371 static inline void 1372 subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 1373 struct sk_buff *skb) {} 1374 static inline bool 1375 mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 1376 struct sk_buff *skb) 1377 { 1378 return false; 1379 } 1380 1381 static inline void mptcp_join_cookie_init(void) {} 1382 #endif 1383 1384 #endif /* __MPTCP_PROTOCOL_H */ 1385