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 41 /* MPTCP option subtypes */ 42 #define MPTCPOPT_MP_CAPABLE 0 43 #define MPTCPOPT_MP_JOIN 1 44 #define MPTCPOPT_DSS 2 45 #define MPTCPOPT_ADD_ADDR 3 46 #define MPTCPOPT_RM_ADDR 4 47 #define MPTCPOPT_MP_PRIO 5 48 #define MPTCPOPT_MP_FAIL 6 49 #define MPTCPOPT_MP_FASTCLOSE 7 50 #define MPTCPOPT_RST 8 51 52 /* MPTCP suboption lengths */ 53 #define TCPOLEN_MPTCP_MPC_SYN 4 54 #define TCPOLEN_MPTCP_MPC_SYNACK 12 55 #define TCPOLEN_MPTCP_MPC_ACK 20 56 #define TCPOLEN_MPTCP_MPC_ACK_DATA 22 57 #define TCPOLEN_MPTCP_MPJ_SYN 12 58 #define TCPOLEN_MPTCP_MPJ_SYNACK 16 59 #define TCPOLEN_MPTCP_MPJ_ACK 24 60 #define TCPOLEN_MPTCP_DSS_BASE 4 61 #define TCPOLEN_MPTCP_DSS_ACK32 4 62 #define TCPOLEN_MPTCP_DSS_ACK64 8 63 #define TCPOLEN_MPTCP_DSS_MAP32 10 64 #define TCPOLEN_MPTCP_DSS_MAP64 14 65 #define TCPOLEN_MPTCP_DSS_CHECKSUM 2 66 #define TCPOLEN_MPTCP_ADD_ADDR 16 67 #define TCPOLEN_MPTCP_ADD_ADDR_PORT 18 68 #define TCPOLEN_MPTCP_ADD_ADDR_BASE 8 69 #define TCPOLEN_MPTCP_ADD_ADDR_BASE_PORT 10 70 #define TCPOLEN_MPTCP_ADD_ADDR6 28 71 #define TCPOLEN_MPTCP_ADD_ADDR6_PORT 30 72 #define TCPOLEN_MPTCP_ADD_ADDR6_BASE 20 73 #define TCPOLEN_MPTCP_ADD_ADDR6_BASE_PORT 22 74 #define TCPOLEN_MPTCP_PORT_LEN 2 75 #define TCPOLEN_MPTCP_PORT_ALIGN 2 76 #define TCPOLEN_MPTCP_RM_ADDR_BASE 3 77 #define TCPOLEN_MPTCP_PRIO 3 78 #define TCPOLEN_MPTCP_PRIO_ALIGN 4 79 #define TCPOLEN_MPTCP_FASTCLOSE 12 80 #define TCPOLEN_MPTCP_RST 4 81 #define TCPOLEN_MPTCP_FAIL 12 82 83 #define TCPOLEN_MPTCP_MPC_ACK_DATA_CSUM (TCPOLEN_MPTCP_DSS_CHECKSUM + TCPOLEN_MPTCP_MPC_ACK_DATA) 84 85 /* MPTCP MP_JOIN flags */ 86 #define MPTCPOPT_BACKUP BIT(0) 87 #define MPTCPOPT_THMAC_LEN 8 88 89 /* MPTCP MP_CAPABLE flags */ 90 #define MPTCP_VERSION_MASK (0x0F) 91 #define MPTCP_CAP_CHECKSUM_REQD BIT(7) 92 #define MPTCP_CAP_EXTENSIBILITY BIT(6) 93 #define MPTCP_CAP_DENY_JOIN_ID0 BIT(5) 94 #define MPTCP_CAP_HMAC_SHA256 BIT(0) 95 #define MPTCP_CAP_FLAG_MASK (0x1F) 96 97 /* MPTCP DSS flags */ 98 #define MPTCP_DSS_DATA_FIN BIT(4) 99 #define MPTCP_DSS_DSN64 BIT(3) 100 #define MPTCP_DSS_HAS_MAP BIT(2) 101 #define MPTCP_DSS_ACK64 BIT(1) 102 #define MPTCP_DSS_HAS_ACK BIT(0) 103 #define MPTCP_DSS_FLAG_MASK (0x1F) 104 105 /* MPTCP ADD_ADDR flags */ 106 #define MPTCP_ADDR_ECHO BIT(0) 107 108 /* MPTCP MP_PRIO flags */ 109 #define MPTCP_PRIO_BKUP BIT(0) 110 111 /* MPTCP TCPRST flags */ 112 #define MPTCP_RST_TRANSIENT BIT(0) 113 114 /* MPTCP socket atomic flags */ 115 #define MPTCP_WORK_RTX 1 116 #define MPTCP_FALLBACK_DONE 2 117 #define MPTCP_WORK_CLOSE_SUBFLOW 3 118 119 /* 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 #define MPTCP_DEQUEUE 8 128 129 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 }; 197 198 enum mptcp_pm_type { 199 MPTCP_PM_TYPE_KERNEL = 0, 200 MPTCP_PM_TYPE_USERSPACE, 201 202 __MPTCP_PM_TYPE_NR, 203 __MPTCP_PM_TYPE_MAX = __MPTCP_PM_TYPE_NR - 1, 204 }; 205 206 /* Status bits below MPTCP_PM_ALREADY_ESTABLISHED need pm worker actions */ 207 #define MPTCP_PM_WORK_MASK ((1 << MPTCP_PM_ALREADY_ESTABLISHED) - 1) 208 209 enum mptcp_addr_signal_status { 210 MPTCP_ADD_ADDR_SIGNAL, 211 MPTCP_ADD_ADDR_ECHO, 212 MPTCP_RM_ADDR_SIGNAL, 213 }; 214 215 /* max value of mptcp_addr_info.id */ 216 #define MPTCP_PM_MAX_ADDR_ID U8_MAX 217 218 struct mptcp_pm_data { 219 struct mptcp_addr_info local; 220 struct mptcp_addr_info remote; 221 struct list_head anno_list; 222 struct list_head userspace_pm_local_addr_list; 223 224 spinlock_t lock; /*protects the whole PM data */ 225 226 struct_group(reset, 227 228 u8 addr_signal; 229 bool server_side; 230 bool work_pending; 231 bool accept_addr; 232 bool accept_subflow; 233 bool remote_deny_join_id0; 234 u8 add_addr_signaled; 235 u8 add_addr_accepted; 236 u8 local_addr_used; 237 u8 pm_type; 238 u8 subflows; 239 u8 status; 240 241 ); 242 243 DECLARE_BITMAP(id_avail_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); 244 struct mptcp_rm_list rm_list_tx; 245 struct mptcp_rm_list rm_list_rx; 246 }; 247 248 struct mptcp_pm_local { 249 struct mptcp_addr_info addr; 250 u8 flags; 251 int ifindex; 252 }; 253 254 struct mptcp_pm_addr_entry { 255 struct list_head list; 256 struct mptcp_addr_info addr; 257 u8 flags; 258 int ifindex; 259 struct socket *lsk; 260 }; 261 262 struct mptcp_data_frag { 263 struct list_head list; 264 u64 data_seq; 265 u16 data_len; 266 u16 offset; 267 u16 overhead; 268 u16 already_sent; 269 struct page *page; 270 }; 271 272 /* MPTCP connection sock */ 273 struct mptcp_sock { 274 /* inet_connection_sock must be the first member */ 275 struct inet_connection_sock sk; 276 u64 local_key; /* protected by the first subflow socket lock 277 * lockless access read 278 */ 279 u64 remote_key; /* same as above */ 280 u64 write_seq; 281 u64 bytes_sent; 282 u64 snd_nxt; 283 u64 bytes_received; 284 u64 ack_seq; 285 atomic64_t rcv_wnd_sent; 286 u64 rcv_data_fin_seq; 287 u64 bytes_retrans; 288 u64 bytes_consumed; 289 int snd_burst; 290 int old_wspace; 291 u64 recovery_snd_nxt; /* in recovery mode accept up to this seq; 292 * recovery related fields are under data_lock 293 * protection 294 */ 295 u64 bytes_acked; 296 u64 snd_una; 297 u64 wnd_end; 298 u32 last_data_sent; 299 u32 last_data_recv; 300 u32 last_ack_recv; 301 unsigned long timer_ival; 302 u32 token; 303 unsigned long flags; 304 unsigned long cb_flags; 305 bool recovery; /* closing subflow write queue reinjected */ 306 bool can_ack; 307 bool fully_established; 308 bool rcv_data_fin; 309 bool snd_data_fin_enable; 310 bool rcv_fastclose; 311 bool use_64bit_ack; /* Set when we received a 64-bit DSN */ 312 bool csum_enabled; 313 bool allow_infinite_fallback; 314 u8 pending_state; /* A subflow asked to set this sk_state, 315 * protected by the msk data lock 316 */ 317 u8 mpc_endpoint_id; 318 u8 recvmsg_inq:1, 319 cork:1, 320 nodelay:1, 321 fastopening:1, 322 in_accept_queue:1, 323 free_first:1, 324 rcvspace_init:1; 325 u32 notsent_lowat; 326 int keepalive_cnt; 327 int keepalive_idle; 328 int keepalive_intvl; 329 struct work_struct work; 330 struct sk_buff *ooo_last_skb; 331 struct rb_root out_of_order_queue; 332 struct list_head conn_list; 333 struct list_head rtx_queue; 334 struct mptcp_data_frag *first_pending; 335 struct list_head join_list; 336 struct sock *first; /* The mptcp ops can safely dereference, using suitable 337 * ONCE annotation, the subflow outside the socket 338 * lock as such sock is freed after close(). 339 */ 340 struct mptcp_pm_data pm; 341 struct mptcp_sched_ops *sched; 342 struct { 343 u32 space; /* bytes copied in last measurement window */ 344 u32 copied; /* bytes copied in this measurement window */ 345 u64 time; /* start time of measurement window */ 346 u64 rtt_us; /* last maximum rtt of subflows */ 347 } rcvq_space; 348 u8 scaling_ratio; 349 bool allow_subflows; 350 351 u32 subflow_id; 352 u32 setsockopt_seq; 353 char ca_name[TCP_CA_NAME_MAX]; 354 355 spinlock_t fallback_lock; /* protects fallback, 356 * allow_infinite_fallback and 357 * allow_join 358 */ 359 }; 360 361 #define mptcp_data_lock(sk) spin_lock_bh(&(sk)->sk_lock.slock) 362 #define mptcp_data_unlock(sk) spin_unlock_bh(&(sk)->sk_lock.slock) 363 364 #define mptcp_for_each_subflow(__msk, __subflow) \ 365 list_for_each_entry(__subflow, &((__msk)->conn_list), node) 366 #define mptcp_for_each_subflow_safe(__msk, __subflow, __tmp) \ 367 list_for_each_entry_safe(__subflow, __tmp, &((__msk)->conn_list), node) 368 #define mptcp_next_subflow(__msk, __subflow) \ 369 list_next_entry_circular(__subflow, &((__msk)->conn_list), node) 370 371 extern struct genl_family mptcp_genl_family; 372 373 static inline void msk_owned_by_me(const struct mptcp_sock *msk) 374 { 375 sock_owned_by_me((const struct sock *)msk); 376 } 377 378 #ifdef CONFIG_DEBUG_NET 379 /* MPTCP-specific: we might (indirectly) call this helper with the wrong sk */ 380 #undef tcp_sk 381 #define tcp_sk(ptr) ({ \ 382 typeof(ptr) _ptr = (ptr); \ 383 WARN_ON(_ptr->sk_protocol != IPPROTO_TCP); \ 384 container_of_const(_ptr, struct tcp_sock, inet_conn.icsk_inet.sk); \ 385 }) 386 #define mptcp_sk(ptr) ({ \ 387 typeof(ptr) _ptr = (ptr); \ 388 WARN_ON(_ptr->sk_protocol != IPPROTO_MPTCP); \ 389 container_of_const(_ptr, struct mptcp_sock, sk.icsk_inet.sk); \ 390 }) 391 392 #else /* !CONFIG_DEBUG_NET */ 393 #define mptcp_sk(ptr) container_of_const(ptr, struct mptcp_sock, sk.icsk_inet.sk) 394 #endif 395 396 static inline int mptcp_win_from_space(const struct sock *sk, int space) 397 { 398 return __tcp_win_from_space(mptcp_sk(sk)->scaling_ratio, space); 399 } 400 401 static inline int mptcp_space_from_win(const struct sock *sk, int win) 402 { 403 return __tcp_space_from_win(mptcp_sk(sk)->scaling_ratio, win); 404 } 405 406 static inline int __mptcp_space(const struct sock *sk) 407 { 408 return mptcp_win_from_space(sk, READ_ONCE(sk->sk_rcvbuf) - 409 sk_rmem_alloc_get(sk)); 410 } 411 412 static inline struct mptcp_data_frag *mptcp_send_head(const struct sock *sk) 413 { 414 const struct mptcp_sock *msk = mptcp_sk(sk); 415 416 return READ_ONCE(msk->first_pending); 417 } 418 419 static inline struct mptcp_data_frag *mptcp_send_next(struct sock *sk) 420 { 421 struct mptcp_sock *msk = mptcp_sk(sk); 422 struct mptcp_data_frag *cur; 423 424 cur = msk->first_pending; 425 return list_is_last(&cur->list, &msk->rtx_queue) ? NULL : 426 list_next_entry(cur, list); 427 } 428 429 static inline struct mptcp_data_frag *mptcp_pending_tail(const struct sock *sk) 430 { 431 const struct mptcp_sock *msk = mptcp_sk(sk); 432 433 if (!msk->first_pending) 434 return NULL; 435 436 if (WARN_ON_ONCE(list_empty(&msk->rtx_queue))) 437 return NULL; 438 439 return list_last_entry(&msk->rtx_queue, struct mptcp_data_frag, list); 440 } 441 442 static inline struct mptcp_data_frag *mptcp_rtx_head(struct sock *sk) 443 { 444 struct mptcp_sock *msk = mptcp_sk(sk); 445 446 if (msk->snd_una == msk->snd_nxt) 447 return NULL; 448 449 return list_first_entry_or_null(&msk->rtx_queue, struct mptcp_data_frag, list); 450 } 451 452 struct csum_pseudo_header { 453 __be64 data_seq; 454 __be32 subflow_seq; 455 __be16 data_len; 456 __sum16 csum; 457 }; 458 459 struct mptcp_subflow_request_sock { 460 struct tcp_request_sock sk; 461 u16 mp_capable : 1, 462 mp_join : 1, 463 backup : 1, 464 request_bkup : 1, 465 csum_reqd : 1, 466 allow_join_id0 : 1; 467 u8 local_id; 468 u8 remote_id; 469 u64 local_key; 470 u64 idsn; 471 u32 token; 472 u32 ssn_offset; 473 u64 thmac; 474 u32 local_nonce; 475 u32 remote_nonce; 476 struct mptcp_sock *msk; 477 struct hlist_nulls_node token_node; 478 }; 479 480 static inline struct mptcp_subflow_request_sock * 481 mptcp_subflow_rsk(const struct request_sock *rsk) 482 { 483 return (struct mptcp_subflow_request_sock *)rsk; 484 } 485 486 struct mptcp_delegated_action { 487 struct napi_struct napi; 488 local_lock_t bh_lock; 489 struct list_head head; 490 }; 491 492 DECLARE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions); 493 494 #define MPTCP_DELEGATE_SCHEDULED 0 495 #define MPTCP_DELEGATE_SEND 1 496 #define MPTCP_DELEGATE_ACK 2 497 #define MPTCP_DELEGATE_SNDBUF 3 498 499 #define MPTCP_DELEGATE_ACTIONS_MASK (~BIT(MPTCP_DELEGATE_SCHEDULED)) 500 /* MPTCP subflow context */ 501 struct mptcp_subflow_context { 502 struct list_head node;/* conn_list of subflows */ 503 504 struct_group(reset, 505 506 unsigned long avg_pacing_rate; /* protected by msk socket lock */ 507 u64 local_key; 508 u64 remote_key; 509 u64 idsn; 510 u64 map_seq; 511 u32 snd_isn; 512 u32 token; 513 u32 rel_write_seq; 514 u32 map_subflow_seq; 515 u32 ssn_offset; 516 u32 map_data_len; 517 __wsum map_data_csum; 518 u32 map_csum_len; 519 u32 request_mptcp : 1, /* send MP_CAPABLE */ 520 request_join : 1, /* send MP_JOIN */ 521 request_bkup : 1, 522 mp_capable : 1, /* remote is MPTCP capable */ 523 mp_join : 1, /* remote is JOINing */ 524 pm_notified : 1, /* PM hook called for established status */ 525 conn_finished : 1, 526 map_valid : 1, 527 map_csum_reqd : 1, 528 map_data_fin : 1, 529 mpc_map : 1, 530 backup : 1, 531 send_mp_prio : 1, 532 send_mp_fail : 1, 533 send_fastclose : 1, 534 send_infinite_map : 1, 535 remote_key_valid : 1, /* received the peer key from */ 536 disposable : 1, /* ctx can be free at ulp release time */ 537 stale : 1, /* unable to snd/rcv data, do not use for xmit */ 538 valid_csum_seen : 1, /* at least one csum validated */ 539 is_mptfo : 1, /* subflow is doing TFO */ 540 close_event_done : 1, /* has done the post-closed part */ 541 mpc_drop : 1, /* the MPC option has been dropped in a rtx */ 542 __unused : 9; 543 bool data_avail; 544 bool scheduled; 545 bool pm_listener; /* a listener managed by the kernel PM? */ 546 bool fully_established; /* path validated */ 547 u32 remote_nonce; 548 u64 thmac; 549 u32 local_nonce; 550 u32 remote_token; 551 union { 552 u8 hmac[MPTCPOPT_HMAC_LEN]; /* MPJ subflow only */ 553 u64 iasn; /* initial ack sequence number, MPC subflows only */ 554 }; 555 s16 local_id; /* if negative not initialized yet */ 556 u8 remote_id; 557 u8 reset_seen:1; 558 u8 reset_transient:1; 559 u8 reset_reason:4; 560 u8 stale_count; 561 562 u32 subflow_id; 563 564 long delegated_status; 565 unsigned long fail_tout; 566 567 ); 568 569 struct list_head delegated_node; /* link into delegated_action, protected by local BH */ 570 571 u32 setsockopt_seq; 572 u32 stale_rcv_tstamp; 573 int cached_sndbuf; /* sndbuf size when last synced with the msk sndbuf, 574 * protected by the msk socket lock 575 */ 576 577 struct sock *tcp_sock; /* tcp sk backpointer */ 578 struct sock *conn; /* parent mptcp_sock */ 579 const struct inet_connection_sock_af_ops *icsk_af_ops; 580 void (*tcp_state_change)(struct sock *sk); 581 void (*tcp_error_report)(struct sock *sk); 582 583 struct rcu_head rcu; 584 }; 585 586 static inline struct mptcp_subflow_context * 587 mptcp_subflow_ctx(const struct sock *sk) 588 { 589 const struct inet_connection_sock *icsk = inet_csk(sk); 590 591 /* Use RCU on icsk_ulp_data only for sock diag code */ 592 return (__force struct mptcp_subflow_context *)icsk->icsk_ulp_data; 593 } 594 595 static inline struct sock * 596 mptcp_subflow_tcp_sock(const struct mptcp_subflow_context *subflow) 597 { 598 return subflow->tcp_sock; 599 } 600 601 static inline void 602 mptcp_subflow_ctx_reset(struct mptcp_subflow_context *subflow) 603 { 604 memset(&subflow->reset, 0, sizeof(subflow->reset)); 605 subflow->request_mptcp = 1; 606 WRITE_ONCE(subflow->local_id, -1); 607 } 608 609 /* Convert reset reasons in MPTCP to enum sk_rst_reason type */ 610 static inline enum sk_rst_reason 611 sk_rst_convert_mptcp_reason(u32 reason) 612 { 613 switch (reason) { 614 case MPTCP_RST_EUNSPEC: 615 return SK_RST_REASON_MPTCP_RST_EUNSPEC; 616 case MPTCP_RST_EMPTCP: 617 return SK_RST_REASON_MPTCP_RST_EMPTCP; 618 case MPTCP_RST_ERESOURCE: 619 return SK_RST_REASON_MPTCP_RST_ERESOURCE; 620 case MPTCP_RST_EPROHIBIT: 621 return SK_RST_REASON_MPTCP_RST_EPROHIBIT; 622 case MPTCP_RST_EWQ2BIG: 623 return SK_RST_REASON_MPTCP_RST_EWQ2BIG; 624 case MPTCP_RST_EBADPERF: 625 return SK_RST_REASON_MPTCP_RST_EBADPERF; 626 case MPTCP_RST_EMIDDLEBOX: 627 return SK_RST_REASON_MPTCP_RST_EMIDDLEBOX; 628 default: 629 /* It should not happen, or else errors may occur 630 * in MPTCP layer 631 */ 632 return SK_RST_REASON_ERROR; 633 } 634 } 635 636 static inline void 637 mptcp_send_active_reset_reason(struct sock *sk) 638 { 639 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 640 enum sk_rst_reason reason; 641 642 reason = sk_rst_convert_mptcp_reason(subflow->reset_reason); 643 tcp_send_active_reset(sk, GFP_ATOMIC, reason); 644 } 645 646 static inline u64 647 mptcp_subflow_get_map_offset(const struct mptcp_subflow_context *subflow) 648 { 649 return tcp_sk(mptcp_subflow_tcp_sock(subflow))->copied_seq - 650 subflow->ssn_offset - 651 subflow->map_subflow_seq; 652 } 653 654 static inline u64 655 mptcp_subflow_get_mapped_dsn(const struct mptcp_subflow_context *subflow) 656 { 657 return subflow->map_seq + mptcp_subflow_get_map_offset(subflow); 658 } 659 660 void mptcp_subflow_process_delegated(struct sock *ssk, long actions); 661 662 static inline void mptcp_subflow_delegate(struct mptcp_subflow_context *subflow, int action) 663 { 664 long old, set_bits = BIT(MPTCP_DELEGATE_SCHEDULED) | BIT(action); 665 struct mptcp_delegated_action *delegated; 666 bool schedule; 667 668 /* the caller held the subflow bh socket lock */ 669 lockdep_assert_in_softirq(); 670 671 /* The implied barrier pairs with tcp_release_cb_override() 672 * mptcp_napi_poll(), and ensures the below list check sees list 673 * updates done prior to delegated status bits changes 674 */ 675 old = set_mask_bits(&subflow->delegated_status, 0, set_bits); 676 if (!(old & BIT(MPTCP_DELEGATE_SCHEDULED))) { 677 if (WARN_ON_ONCE(!list_empty(&subflow->delegated_node))) 678 return; 679 680 local_lock_nested_bh(&mptcp_delegated_actions.bh_lock); 681 delegated = this_cpu_ptr(&mptcp_delegated_actions); 682 schedule = list_empty(&delegated->head); 683 list_add_tail(&subflow->delegated_node, &delegated->head); 684 local_unlock_nested_bh(&mptcp_delegated_actions.bh_lock); 685 sock_hold(mptcp_subflow_tcp_sock(subflow)); 686 if (schedule) 687 napi_schedule(&delegated->napi); 688 } 689 } 690 691 static inline struct mptcp_subflow_context * 692 mptcp_subflow_delegated_next(struct mptcp_delegated_action *delegated) 693 { 694 struct mptcp_subflow_context *ret; 695 696 local_lock_nested_bh(&mptcp_delegated_actions.bh_lock); 697 if (list_empty(&delegated->head)) { 698 local_unlock_nested_bh(&mptcp_delegated_actions.bh_lock); 699 return NULL; 700 } 701 702 ret = list_first_entry(&delegated->head, struct mptcp_subflow_context, delegated_node); 703 list_del_init(&ret->delegated_node); 704 local_unlock_nested_bh(&mptcp_delegated_actions.bh_lock); 705 return ret; 706 } 707 708 int mptcp_is_enabled(const struct net *net); 709 unsigned int mptcp_get_add_addr_timeout(const struct net *net); 710 int mptcp_is_checksum_enabled(const struct net *net); 711 int mptcp_allow_join_id0(const struct net *net); 712 unsigned int mptcp_stale_loss_cnt(const struct net *net); 713 unsigned int mptcp_close_timeout(const struct sock *sk); 714 int mptcp_get_pm_type(const struct net *net); 715 const char *mptcp_get_path_manager(const struct net *net); 716 const char *mptcp_get_scheduler(const struct net *net); 717 718 void mptcp_active_disable(struct sock *sk); 719 bool mptcp_active_should_disable(struct sock *ssk); 720 void mptcp_active_enable(struct sock *sk); 721 722 void mptcp_get_available_schedulers(char *buf, size_t maxlen); 723 void __mptcp_subflow_fully_established(struct mptcp_sock *msk, 724 struct mptcp_subflow_context *subflow, 725 const struct mptcp_options_received *mp_opt); 726 bool __mptcp_retransmit_pending_data(struct sock *sk); 727 void mptcp_check_and_set_pending(struct sock *sk); 728 void __mptcp_push_pending(struct sock *sk, unsigned int flags); 729 bool mptcp_subflow_data_available(struct sock *sk); 730 void __init mptcp_subflow_init(void); 731 void mptcp_subflow_shutdown(struct sock *sk, struct sock *ssk, int how); 732 void mptcp_close_ssk(struct sock *sk, struct sock *ssk, 733 struct mptcp_subflow_context *subflow); 734 void __mptcp_subflow_send_ack(struct sock *ssk); 735 void mptcp_subflow_reset(struct sock *ssk); 736 void mptcp_subflow_queue_clean(struct sock *sk, struct sock *ssk); 737 void mptcp_sock_graft(struct sock *sk, struct socket *parent); 738 struct sock *__mptcp_nmpc_sk(struct mptcp_sock *msk); 739 bool __mptcp_close(struct sock *sk, long timeout); 740 void mptcp_cancel_work(struct sock *sk); 741 void __mptcp_unaccepted_force_close(struct sock *sk); 742 void mptcp_set_state(struct sock *sk, int state); 743 744 bool mptcp_addresses_equal(const struct mptcp_addr_info *a, 745 const struct mptcp_addr_info *b, bool use_port); 746 void mptcp_local_address(const struct sock_common *skc, 747 struct mptcp_addr_info *addr); 748 void mptcp_remote_address(const struct sock_common *skc, 749 struct mptcp_addr_info *addr); 750 751 /* called with sk socket lock held */ 752 int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_pm_local *local, 753 const struct mptcp_addr_info *remote); 754 int mptcp_subflow_create_socket(struct sock *sk, unsigned short family, 755 struct socket **new_sock); 756 void mptcp_info2sockaddr(const struct mptcp_addr_info *info, 757 struct sockaddr_storage *addr, 758 unsigned short family); 759 struct mptcp_sched_ops *mptcp_sched_find(const char *name); 760 int mptcp_validate_scheduler(struct mptcp_sched_ops *sched); 761 int mptcp_register_scheduler(struct mptcp_sched_ops *sched); 762 void mptcp_unregister_scheduler(struct mptcp_sched_ops *sched); 763 void mptcp_sched_init(void); 764 int mptcp_init_sched(struct mptcp_sock *msk, 765 struct mptcp_sched_ops *sched); 766 void mptcp_release_sched(struct mptcp_sock *msk); 767 void mptcp_subflow_set_scheduled(struct mptcp_subflow_context *subflow, 768 bool scheduled); 769 struct sock *mptcp_subflow_get_send(struct mptcp_sock *msk); 770 struct sock *mptcp_subflow_get_retrans(struct mptcp_sock *msk); 771 int mptcp_sched_get_send(struct mptcp_sock *msk); 772 int mptcp_sched_get_retrans(struct mptcp_sock *msk); 773 774 static inline u64 mptcp_data_avail(const struct mptcp_sock *msk) 775 { 776 return READ_ONCE(msk->bytes_received) - READ_ONCE(msk->bytes_consumed); 777 } 778 779 static inline bool mptcp_epollin_ready(const struct sock *sk) 780 { 781 u64 data_avail = mptcp_data_avail(mptcp_sk(sk)); 782 783 if (!data_avail) 784 return false; 785 786 /* mptcp doesn't have to deal with small skbs in the receive queue, 787 * as it can always coalesce them 788 */ 789 return (data_avail >= sk->sk_rcvlowat) || 790 (mem_cgroup_sockets_enabled && sk->sk_memcg && 791 mem_cgroup_under_socket_pressure(sk->sk_memcg)) || 792 READ_ONCE(tcp_memory_pressure); 793 } 794 795 int mptcp_set_rcvlowat(struct sock *sk, int val); 796 797 static inline bool __tcp_can_send(const struct sock *ssk) 798 { 799 /* only send if our side has not closed yet */ 800 return ((1 << inet_sk_state_load(ssk)) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)); 801 } 802 803 static inline bool __mptcp_subflow_active(struct mptcp_subflow_context *subflow) 804 { 805 /* can't send if JOIN hasn't completed yet (i.e. is usable for mptcp) */ 806 if (subflow->request_join && !READ_ONCE(subflow->fully_established)) 807 return false; 808 809 return __tcp_can_send(mptcp_subflow_tcp_sock(subflow)); 810 } 811 812 void mptcp_subflow_set_active(struct mptcp_subflow_context *subflow); 813 814 bool mptcp_subflow_active(struct mptcp_subflow_context *subflow); 815 816 void mptcp_subflow_drop_ctx(struct sock *ssk); 817 818 static inline void mptcp_subflow_tcp_fallback(struct sock *sk, 819 struct mptcp_subflow_context *ctx) 820 { 821 sk->sk_data_ready = sock_def_readable; 822 sk->sk_state_change = ctx->tcp_state_change; 823 sk->sk_write_space = sk_stream_write_space; 824 sk->sk_error_report = ctx->tcp_error_report; 825 826 inet_csk(sk)->icsk_af_ops = ctx->icsk_af_ops; 827 } 828 829 void __init mptcp_proto_init(void); 830 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 831 int __init mptcp_proto_v6_init(void); 832 #endif 833 834 struct sock *mptcp_sk_clone_init(const struct sock *sk, 835 const struct mptcp_options_received *mp_opt, 836 struct sock *ssk, 837 struct request_sock *req); 838 void mptcp_get_options(const struct sk_buff *skb, 839 struct mptcp_options_received *mp_opt); 840 841 void mptcp_finish_connect(struct sock *sk); 842 void __mptcp_sync_state(struct sock *sk, int state); 843 void mptcp_reset_tout_timer(struct mptcp_sock *msk, unsigned long fail_tout); 844 845 static inline void mptcp_stop_tout_timer(struct sock *sk) 846 { 847 if (!inet_csk(sk)->icsk_mtup.probe_timestamp) 848 return; 849 850 sk_stop_timer(sk, &sk->sk_timer); 851 inet_csk(sk)->icsk_mtup.probe_timestamp = 0; 852 } 853 854 static inline void mptcp_set_close_tout(struct sock *sk, unsigned long tout) 855 { 856 /* avoid 0 timestamp, as that means no close timeout */ 857 inet_csk(sk)->icsk_mtup.probe_timestamp = tout ? : 1; 858 } 859 860 static inline void mptcp_start_tout_timer(struct sock *sk) 861 { 862 mptcp_set_close_tout(sk, tcp_jiffies32); 863 mptcp_reset_tout_timer(mptcp_sk(sk), 0); 864 } 865 866 static inline bool mptcp_is_fully_established(struct sock *sk) 867 { 868 return inet_sk_state_load(sk) == TCP_ESTABLISHED && 869 READ_ONCE(mptcp_sk(sk)->fully_established); 870 } 871 872 void mptcp_rcv_space_init(struct mptcp_sock *msk, const struct sock *ssk); 873 void mptcp_data_ready(struct sock *sk, struct sock *ssk); 874 bool mptcp_finish_join(struct sock *sk); 875 bool mptcp_schedule_work(struct sock *sk); 876 int mptcp_setsockopt(struct sock *sk, int level, int optname, 877 sockptr_t optval, unsigned int optlen); 878 int mptcp_getsockopt(struct sock *sk, int level, int optname, 879 char __user *optval, int __user *option); 880 881 u64 __mptcp_expand_seq(u64 old_seq, u64 cur_seq); 882 static inline u64 mptcp_expand_seq(u64 old_seq, u64 cur_seq, bool use_64bit) 883 { 884 if (use_64bit) 885 return cur_seq; 886 887 return __mptcp_expand_seq(old_seq, cur_seq); 888 } 889 void __mptcp_check_push(struct sock *sk, struct sock *ssk); 890 void __mptcp_data_acked(struct sock *sk); 891 void __mptcp_error_report(struct sock *sk); 892 bool mptcp_update_rcv_data_fin(struct mptcp_sock *msk, u64 data_fin_seq, bool use_64bit); 893 static inline bool mptcp_data_fin_enabled(const struct mptcp_sock *msk) 894 { 895 return READ_ONCE(msk->snd_data_fin_enable) && 896 READ_ONCE(msk->write_seq) == READ_ONCE(msk->snd_nxt); 897 } 898 899 static inline u32 mptcp_notsent_lowat(const struct sock *sk) 900 { 901 struct net *net = sock_net(sk); 902 u32 val; 903 904 val = READ_ONCE(mptcp_sk(sk)->notsent_lowat); 905 return val ?: READ_ONCE(net->ipv4.sysctl_tcp_notsent_lowat); 906 } 907 908 static inline bool mptcp_stream_memory_free(const struct sock *sk, int wake) 909 { 910 const struct mptcp_sock *msk = mptcp_sk(sk); 911 u32 notsent_bytes; 912 913 notsent_bytes = READ_ONCE(msk->write_seq) - READ_ONCE(msk->snd_nxt); 914 return (notsent_bytes << wake) < mptcp_notsent_lowat(sk); 915 } 916 917 static inline bool __mptcp_stream_is_writeable(const struct sock *sk, int wake) 918 { 919 return mptcp_stream_memory_free(sk, wake) && 920 __sk_stream_is_writeable(sk, wake); 921 } 922 923 static inline void mptcp_write_space(struct sock *sk) 924 { 925 /* pairs with memory barrier in mptcp_poll */ 926 smp_mb(); 927 if (mptcp_stream_memory_free(sk, 1)) 928 sk_stream_write_space(sk); 929 } 930 931 static inline void __mptcp_sync_sndbuf(struct sock *sk) 932 { 933 struct mptcp_subflow_context *subflow; 934 int ssk_sndbuf, new_sndbuf; 935 936 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) 937 return; 938 939 new_sndbuf = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_wmem[0]); 940 mptcp_for_each_subflow(mptcp_sk(sk), subflow) { 941 ssk_sndbuf = READ_ONCE(mptcp_subflow_tcp_sock(subflow)->sk_sndbuf); 942 943 subflow->cached_sndbuf = ssk_sndbuf; 944 new_sndbuf += ssk_sndbuf; 945 } 946 947 /* the msk max wmem limit is <nr_subflows> * tcp wmem[2] */ 948 WRITE_ONCE(sk->sk_sndbuf, new_sndbuf); 949 mptcp_write_space(sk); 950 } 951 952 /* The called held both the msk socket and the subflow socket locks, 953 * possibly under BH 954 */ 955 static inline void __mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk) 956 { 957 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 958 959 if (READ_ONCE(ssk->sk_sndbuf) != subflow->cached_sndbuf) 960 __mptcp_sync_sndbuf(sk); 961 } 962 963 /* the caller held only the subflow socket lock, either in process or 964 * BH context. Additionally this can be called under the msk data lock, 965 * so we can't acquire such lock here: let the delegate action acquires 966 * the needed locks in suitable order. 967 */ 968 static inline void mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk) 969 { 970 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 971 972 if (likely(READ_ONCE(ssk->sk_sndbuf) == subflow->cached_sndbuf)) 973 return; 974 975 local_bh_disable(); 976 mptcp_subflow_delegate(subflow, MPTCP_DELEGATE_SNDBUF); 977 local_bh_enable(); 978 } 979 980 void mptcp_destroy_common(struct mptcp_sock *msk, unsigned int flags); 981 982 #define MPTCP_TOKEN_MAX_RETRIES 4 983 984 void __init mptcp_token_init(void); 985 static inline void mptcp_token_init_request(struct request_sock *req) 986 { 987 mptcp_subflow_rsk(req)->token_node.pprev = NULL; 988 } 989 990 int mptcp_token_new_request(struct request_sock *req); 991 void mptcp_token_destroy_request(struct request_sock *req); 992 int mptcp_token_new_connect(struct sock *ssk); 993 void mptcp_token_accept(struct mptcp_subflow_request_sock *r, 994 struct mptcp_sock *msk); 995 bool mptcp_token_exists(u32 token); 996 struct mptcp_sock *mptcp_token_get_sock(struct net *net, u32 token); 997 struct mptcp_sock *mptcp_token_iter_next(const struct net *net, long *s_slot, 998 long *s_num); 999 void mptcp_token_destroy(struct mptcp_sock *msk); 1000 1001 void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn); 1002 1003 void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u8 *msg, int len, void *hmac); 1004 __sum16 __mptcp_make_csum(u64 data_seq, u32 subflow_seq, u16 data_len, __wsum sum); 1005 1006 void __init mptcp_pm_init(void); 1007 void mptcp_pm_data_init(struct mptcp_sock *msk); 1008 void mptcp_pm_data_reset(struct mptcp_sock *msk); 1009 void mptcp_pm_destroy(struct mptcp_sock *msk); 1010 int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info, 1011 struct mptcp_addr_info *addr); 1012 int mptcp_pm_parse_entry(struct nlattr *attr, struct genl_info *info, 1013 bool require_family, 1014 struct mptcp_pm_addr_entry *entry); 1015 bool mptcp_pm_addr_families_match(const struct sock *sk, 1016 const struct mptcp_addr_info *loc, 1017 const struct mptcp_addr_info *rem); 1018 void mptcp_pm_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); 1019 void mptcp_pm_new_connection(struct mptcp_sock *msk, const struct sock *ssk, int server_side); 1020 void mptcp_pm_fully_established(struct mptcp_sock *msk, const struct sock *ssk); 1021 bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk); 1022 void mptcp_pm_connection_closed(struct mptcp_sock *msk); 1023 void mptcp_pm_subflow_established(struct mptcp_sock *msk); 1024 bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk); 1025 void mptcp_pm_subflow_check_next(struct mptcp_sock *msk, 1026 const struct mptcp_subflow_context *subflow); 1027 void mptcp_pm_add_addr_received(const struct sock *ssk, 1028 const struct mptcp_addr_info *addr); 1029 void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk, 1030 const struct mptcp_addr_info *addr); 1031 void mptcp_pm_add_addr_send_ack(struct mptcp_sock *msk); 1032 void mptcp_pm_send_ack(struct mptcp_sock *msk, 1033 struct mptcp_subflow_context *subflow, 1034 bool prio, bool backup); 1035 void mptcp_pm_addr_send_ack(struct mptcp_sock *msk); 1036 void mptcp_pm_nl_rm_addr(struct mptcp_sock *msk, u8 rm_id); 1037 void mptcp_pm_rm_subflow(struct mptcp_sock *msk, 1038 const struct mptcp_rm_list *rm_list); 1039 void mptcp_pm_rm_addr_received(struct mptcp_sock *msk, 1040 const struct mptcp_rm_list *rm_list); 1041 void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup); 1042 void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq); 1043 int mptcp_pm_mp_prio_send_ack(struct mptcp_sock *msk, 1044 struct mptcp_addr_info *addr, 1045 struct mptcp_addr_info *rem, 1046 u8 bkup); 1047 bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk, 1048 const struct mptcp_addr_info *addr); 1049 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk); 1050 struct mptcp_pm_add_entry * 1051 mptcp_pm_del_add_timer(struct mptcp_sock *msk, 1052 const struct mptcp_addr_info *addr, bool check_id); 1053 bool mptcp_lookup_subflow_by_saddr(const struct list_head *list, 1054 const struct mptcp_addr_info *saddr); 1055 bool mptcp_remove_anno_list_by_saddr(struct mptcp_sock *msk, 1056 const struct mptcp_addr_info *addr); 1057 int mptcp_pm_nl_set_flags(struct mptcp_pm_addr_entry *local, 1058 struct genl_info *info); 1059 int mptcp_userspace_pm_set_flags(struct mptcp_pm_addr_entry *local, 1060 struct genl_info *info); 1061 int mptcp_pm_announce_addr(struct mptcp_sock *msk, 1062 const struct mptcp_addr_info *addr, 1063 bool echo); 1064 int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); 1065 void mptcp_pm_remove_addr_entry(struct mptcp_sock *msk, 1066 struct mptcp_pm_addr_entry *entry); 1067 1068 /* the default path manager, used in mptcp_pm_unregister */ 1069 extern struct mptcp_pm_ops mptcp_pm_kernel; 1070 1071 struct mptcp_pm_ops *mptcp_pm_find(const char *name); 1072 int mptcp_pm_register(struct mptcp_pm_ops *pm_ops); 1073 void mptcp_pm_unregister(struct mptcp_pm_ops *pm_ops); 1074 int mptcp_pm_validate(struct mptcp_pm_ops *pm_ops); 1075 void mptcp_pm_get_available(char *buf, size_t maxlen); 1076 1077 void mptcp_userspace_pm_free_local_addr_list(struct mptcp_sock *msk); 1078 1079 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk, 1080 const struct sock *ssk, gfp_t gfp); 1081 void mptcp_event_addr_announced(const struct sock *ssk, const struct mptcp_addr_info *info); 1082 void mptcp_event_addr_removed(const struct mptcp_sock *msk, u8 id); 1083 void mptcp_event_pm_listener(const struct sock *ssk, 1084 enum mptcp_event_type event); 1085 bool mptcp_userspace_pm_active(const struct mptcp_sock *msk); 1086 1087 void mptcp_fastopen_subflow_synack_set_params(struct mptcp_subflow_context *subflow, 1088 struct request_sock *req); 1089 int mptcp_pm_genl_fill_addr(struct sk_buff *msg, 1090 struct netlink_callback *cb, 1091 struct mptcp_pm_addr_entry *entry); 1092 1093 static inline bool mptcp_pm_should_add_signal(struct mptcp_sock *msk) 1094 { 1095 return READ_ONCE(msk->pm.addr_signal) & 1096 (BIT(MPTCP_ADD_ADDR_SIGNAL) | BIT(MPTCP_ADD_ADDR_ECHO)); 1097 } 1098 1099 static inline bool mptcp_pm_should_add_signal_addr(struct mptcp_sock *msk) 1100 { 1101 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_SIGNAL); 1102 } 1103 1104 static inline bool mptcp_pm_should_add_signal_echo(struct mptcp_sock *msk) 1105 { 1106 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_ECHO); 1107 } 1108 1109 static inline bool mptcp_pm_should_rm_signal(struct mptcp_sock *msk) 1110 { 1111 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_RM_ADDR_SIGNAL); 1112 } 1113 1114 static inline bool mptcp_pm_is_userspace(const struct mptcp_sock *msk) 1115 { 1116 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_USERSPACE; 1117 } 1118 1119 static inline bool mptcp_pm_is_kernel(const struct mptcp_sock *msk) 1120 { 1121 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_KERNEL; 1122 } 1123 1124 static inline unsigned int mptcp_add_addr_len(int family, bool echo, bool port) 1125 { 1126 u8 len = TCPOLEN_MPTCP_ADD_ADDR_BASE; 1127 1128 if (family == AF_INET6) 1129 len = TCPOLEN_MPTCP_ADD_ADDR6_BASE; 1130 if (!echo) 1131 len += MPTCPOPT_THMAC_LEN; 1132 /* account for 2 trailing 'nop' options */ 1133 if (port) 1134 len += TCPOLEN_MPTCP_PORT_LEN + TCPOLEN_MPTCP_PORT_ALIGN; 1135 1136 return len; 1137 } 1138 1139 static inline int mptcp_rm_addr_len(const struct mptcp_rm_list *rm_list) 1140 { 1141 if (rm_list->nr == 0 || rm_list->nr > MPTCP_RM_IDS_MAX) 1142 return -EINVAL; 1143 1144 return TCPOLEN_MPTCP_RM_ADDR_BASE + roundup(rm_list->nr - 1, 4) + 1; 1145 } 1146 1147 bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, const struct sk_buff *skb, 1148 unsigned int opt_size, unsigned int remaining, 1149 struct mptcp_addr_info *addr, bool *echo, 1150 bool *drop_other_suboptions); 1151 bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining, 1152 struct mptcp_rm_list *rm_list); 1153 int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc); 1154 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, 1155 struct mptcp_pm_addr_entry *skc); 1156 int mptcp_userspace_pm_get_local_id(struct mptcp_sock *msk, 1157 struct mptcp_pm_addr_entry *skc); 1158 bool mptcp_pm_is_backup(struct mptcp_sock *msk, struct sock_common *skc); 1159 bool mptcp_pm_nl_is_backup(struct mptcp_sock *msk, struct mptcp_addr_info *skc); 1160 bool mptcp_userspace_pm_is_backup(struct mptcp_sock *msk, struct mptcp_addr_info *skc); 1161 int mptcp_pm_nl_dump_addr(struct sk_buff *msg, 1162 struct netlink_callback *cb); 1163 int mptcp_userspace_pm_dump_addr(struct sk_buff *msg, 1164 struct netlink_callback *cb); 1165 int mptcp_pm_nl_get_addr(u8 id, struct mptcp_pm_addr_entry *addr, 1166 struct genl_info *info); 1167 int mptcp_userspace_pm_get_addr(u8 id, struct mptcp_pm_addr_entry *addr, 1168 struct genl_info *info); 1169 1170 static inline u8 subflow_get_local_id(const struct mptcp_subflow_context *subflow) 1171 { 1172 int local_id = READ_ONCE(subflow->local_id); 1173 1174 if (local_id < 0) 1175 return 0; 1176 return local_id; 1177 } 1178 1179 void __init mptcp_pm_kernel_register(void); 1180 void __init mptcp_pm_userspace_register(void); 1181 void __init mptcp_pm_nl_init(void); 1182 void mptcp_pm_worker(struct mptcp_sock *msk); 1183 void __mptcp_pm_kernel_worker(struct mptcp_sock *msk); 1184 unsigned int mptcp_pm_get_add_addr_signal_max(const struct mptcp_sock *msk); 1185 unsigned int mptcp_pm_get_add_addr_accept_max(const struct mptcp_sock *msk); 1186 unsigned int mptcp_pm_get_subflows_max(const struct mptcp_sock *msk); 1187 unsigned int mptcp_pm_get_local_addr_max(const struct mptcp_sock *msk); 1188 1189 /* called under PM lock */ 1190 static inline void __mptcp_pm_close_subflow(struct mptcp_sock *msk) 1191 { 1192 if (--msk->pm.subflows < mptcp_pm_get_subflows_max(msk)) 1193 WRITE_ONCE(msk->pm.accept_subflow, true); 1194 } 1195 1196 static inline void mptcp_pm_close_subflow(struct mptcp_sock *msk) 1197 { 1198 spin_lock_bh(&msk->pm.lock); 1199 __mptcp_pm_close_subflow(msk); 1200 spin_unlock_bh(&msk->pm.lock); 1201 } 1202 1203 void mptcp_sockopt_sync_locked(struct mptcp_sock *msk, struct sock *ssk); 1204 1205 static inline struct mptcp_ext *mptcp_get_ext(const struct sk_buff *skb) 1206 { 1207 return (struct mptcp_ext *)skb_ext_find(skb, SKB_EXT_MPTCP); 1208 } 1209 1210 void mptcp_diag_subflow_init(struct tcp_ulp_ops *ops); 1211 1212 static inline bool __mptcp_check_fallback(const struct mptcp_sock *msk) 1213 { 1214 return test_bit(MPTCP_FALLBACK_DONE, &msk->flags); 1215 } 1216 1217 static inline bool mptcp_check_fallback(const struct sock *sk) 1218 { 1219 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 1220 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 1221 1222 return __mptcp_check_fallback(msk); 1223 } 1224 1225 static inline bool __mptcp_try_fallback(struct mptcp_sock *msk) 1226 { 1227 if (__mptcp_check_fallback(msk)) { 1228 pr_debug("TCP fallback already done (msk=%p)\n", msk); 1229 return true; 1230 } 1231 spin_lock_bh(&msk->fallback_lock); 1232 if (!msk->allow_infinite_fallback) { 1233 spin_unlock_bh(&msk->fallback_lock); 1234 return false; 1235 } 1236 1237 msk->allow_subflows = false; 1238 set_bit(MPTCP_FALLBACK_DONE, &msk->flags); 1239 spin_unlock_bh(&msk->fallback_lock); 1240 return true; 1241 } 1242 1243 static inline bool __mptcp_has_initial_subflow(const struct mptcp_sock *msk) 1244 { 1245 struct sock *ssk = READ_ONCE(msk->first); 1246 1247 return ssk && ((1 << inet_sk_state_load(ssk)) & 1248 (TCPF_ESTABLISHED | TCPF_SYN_SENT | 1249 TCPF_SYN_RECV | TCPF_LISTEN)); 1250 } 1251 1252 static inline bool mptcp_try_fallback(struct sock *ssk) 1253 { 1254 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 1255 struct sock *sk = subflow->conn; 1256 struct mptcp_sock *msk; 1257 1258 msk = mptcp_sk(sk); 1259 if (!__mptcp_try_fallback(msk)) 1260 return false; 1261 if (READ_ONCE(msk->snd_data_fin_enable) && !(ssk->sk_shutdown & SEND_SHUTDOWN)) { 1262 gfp_t saved_allocation = ssk->sk_allocation; 1263 1264 /* we are in a atomic (BH) scope, override ssk default for data 1265 * fin allocation 1266 */ 1267 ssk->sk_allocation = GFP_ATOMIC; 1268 ssk->sk_shutdown |= SEND_SHUTDOWN; 1269 tcp_shutdown(ssk, SEND_SHUTDOWN); 1270 ssk->sk_allocation = saved_allocation; 1271 } 1272 return true; 1273 } 1274 1275 #define pr_fallback(a) pr_debug("%s:fallback to TCP (msk=%p)\n", __func__, a) 1276 1277 static inline void mptcp_subflow_early_fallback(struct mptcp_sock *msk, 1278 struct mptcp_subflow_context *subflow) 1279 { 1280 pr_fallback(msk); 1281 subflow->request_mptcp = 0; 1282 WARN_ON_ONCE(!__mptcp_try_fallback(msk)); 1283 } 1284 1285 static inline bool mptcp_check_infinite_map(struct sk_buff *skb) 1286 { 1287 struct mptcp_ext *mpext; 1288 1289 mpext = skb ? mptcp_get_ext(skb) : NULL; 1290 if (mpext && mpext->infinite_map) 1291 return true; 1292 1293 return false; 1294 } 1295 1296 static inline bool is_active_ssk(struct mptcp_subflow_context *subflow) 1297 { 1298 return (subflow->request_mptcp || subflow->request_join); 1299 } 1300 1301 static inline bool subflow_simultaneous_connect(struct sock *sk) 1302 { 1303 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 1304 1305 return (1 << sk->sk_state) & 1306 (TCPF_ESTABLISHED | TCPF_FIN_WAIT1 | TCPF_FIN_WAIT2 | TCPF_CLOSING) && 1307 is_active_ssk(subflow) && 1308 !subflow->conn_finished; 1309 } 1310 1311 #ifdef CONFIG_SYN_COOKIES 1312 void subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 1313 struct sk_buff *skb); 1314 bool mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 1315 struct sk_buff *skb); 1316 void __init mptcp_join_cookie_init(void); 1317 #else 1318 static inline void 1319 subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 1320 struct sk_buff *skb) {} 1321 static inline bool 1322 mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 1323 struct sk_buff *skb) 1324 { 1325 return false; 1326 } 1327 1328 static inline void mptcp_join_cookie_init(void) {} 1329 #endif 1330 1331 #endif /* __MPTCP_PROTOCOL_H */ 1332