1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* Multipath TCP 3 * 4 * Copyright (c) 2017 - 2019, Intel Corporation. 5 */ 6 7 #ifndef __MPTCP_PROTOCOL_H 8 #define __MPTCP_PROTOCOL_H 9 10 #include <linux/random.h> 11 #include <net/tcp.h> 12 #include <net/inet_connection_sock.h> 13 #include <uapi/linux/mptcp.h> 14 #include <net/genetlink.h> 15 16 #define MPTCP_SUPPORTED_VERSION 1 17 18 /* MPTCP option bits */ 19 #define OPTION_MPTCP_MPC_SYN BIT(0) 20 #define OPTION_MPTCP_MPC_SYNACK BIT(1) 21 #define OPTION_MPTCP_MPC_ACK BIT(2) 22 #define OPTION_MPTCP_MPJ_SYN BIT(3) 23 #define OPTION_MPTCP_MPJ_SYNACK BIT(4) 24 #define OPTION_MPTCP_MPJ_ACK BIT(5) 25 #define OPTION_MPTCP_ADD_ADDR BIT(6) 26 #define OPTION_MPTCP_RM_ADDR BIT(7) 27 #define OPTION_MPTCP_FASTCLOSE BIT(8) 28 #define OPTION_MPTCP_PRIO BIT(9) 29 #define OPTION_MPTCP_RST BIT(10) 30 #define OPTION_MPTCP_DSS BIT(11) 31 #define OPTION_MPTCP_FAIL BIT(12) 32 33 #define OPTION_MPTCP_CSUMREQD BIT(13) 34 35 #define OPTIONS_MPTCP_MPC (OPTION_MPTCP_MPC_SYN | OPTION_MPTCP_MPC_SYNACK | \ 36 OPTION_MPTCP_MPC_ACK) 37 #define OPTIONS_MPTCP_MPJ (OPTION_MPTCP_MPJ_SYN | OPTION_MPTCP_MPJ_SYNACK | \ 38 OPTION_MPTCP_MPJ_ACK) 39 40 /* MPTCP option subtypes */ 41 #define MPTCPOPT_MP_CAPABLE 0 42 #define MPTCPOPT_MP_JOIN 1 43 #define MPTCPOPT_DSS 2 44 #define MPTCPOPT_ADD_ADDR 3 45 #define MPTCPOPT_RM_ADDR 4 46 #define MPTCPOPT_MP_PRIO 5 47 #define MPTCPOPT_MP_FAIL 6 48 #define MPTCPOPT_MP_FASTCLOSE 7 49 #define MPTCPOPT_RST 8 50 51 /* MPTCP suboption lengths */ 52 #define TCPOLEN_MPTCP_MPC_SYN 4 53 #define TCPOLEN_MPTCP_MPC_SYNACK 12 54 #define TCPOLEN_MPTCP_MPC_ACK 20 55 #define TCPOLEN_MPTCP_MPC_ACK_DATA 22 56 #define TCPOLEN_MPTCP_MPJ_SYN 12 57 #define TCPOLEN_MPTCP_MPJ_SYNACK 16 58 #define TCPOLEN_MPTCP_MPJ_ACK 24 59 #define TCPOLEN_MPTCP_DSS_BASE 4 60 #define TCPOLEN_MPTCP_DSS_ACK32 4 61 #define TCPOLEN_MPTCP_DSS_ACK64 8 62 #define TCPOLEN_MPTCP_DSS_MAP32 10 63 #define TCPOLEN_MPTCP_DSS_MAP64 14 64 #define TCPOLEN_MPTCP_DSS_CHECKSUM 2 65 #define TCPOLEN_MPTCP_ADD_ADDR 16 66 #define TCPOLEN_MPTCP_ADD_ADDR_PORT 18 67 #define TCPOLEN_MPTCP_ADD_ADDR_BASE 8 68 #define TCPOLEN_MPTCP_ADD_ADDR_BASE_PORT 10 69 #define TCPOLEN_MPTCP_ADD_ADDR6 28 70 #define TCPOLEN_MPTCP_ADD_ADDR6_PORT 30 71 #define TCPOLEN_MPTCP_ADD_ADDR6_BASE 20 72 #define TCPOLEN_MPTCP_ADD_ADDR6_BASE_PORT 22 73 #define TCPOLEN_MPTCP_PORT_LEN 2 74 #define TCPOLEN_MPTCP_PORT_ALIGN 2 75 #define TCPOLEN_MPTCP_RM_ADDR_BASE 3 76 #define TCPOLEN_MPTCP_PRIO 3 77 #define TCPOLEN_MPTCP_PRIO_ALIGN 4 78 #define TCPOLEN_MPTCP_FASTCLOSE 12 79 #define TCPOLEN_MPTCP_RST 4 80 #define TCPOLEN_MPTCP_FAIL 12 81 82 #define TCPOLEN_MPTCP_MPC_ACK_DATA_CSUM (TCPOLEN_MPTCP_DSS_CHECKSUM + TCPOLEN_MPTCP_MPC_ACK_DATA) 83 84 /* MPTCP MP_JOIN flags */ 85 #define MPTCPOPT_BACKUP BIT(0) 86 #define MPTCPOPT_THMAC_LEN 8 87 88 /* MPTCP MP_CAPABLE flags */ 89 #define MPTCP_VERSION_MASK (0x0F) 90 #define MPTCP_CAP_CHECKSUM_REQD BIT(7) 91 #define MPTCP_CAP_EXTENSIBILITY BIT(6) 92 #define MPTCP_CAP_DENY_JOIN_ID0 BIT(5) 93 #define MPTCP_CAP_HMAC_SHA256 BIT(0) 94 #define MPTCP_CAP_FLAG_MASK (0x1F) 95 96 /* MPTCP DSS flags */ 97 #define MPTCP_DSS_DATA_FIN BIT(4) 98 #define MPTCP_DSS_DSN64 BIT(3) 99 #define MPTCP_DSS_HAS_MAP BIT(2) 100 #define MPTCP_DSS_ACK64 BIT(1) 101 #define MPTCP_DSS_HAS_ACK BIT(0) 102 #define MPTCP_DSS_FLAG_MASK (0x1F) 103 104 /* MPTCP ADD_ADDR flags */ 105 #define MPTCP_ADDR_ECHO BIT(0) 106 107 /* MPTCP MP_PRIO flags */ 108 #define MPTCP_PRIO_BKUP BIT(0) 109 110 /* MPTCP TCPRST flags */ 111 #define MPTCP_RST_TRANSIENT BIT(0) 112 113 /* MPTCP socket atomic flags */ 114 #define MPTCP_NOSPACE 1 115 #define MPTCP_WORK_RTX 2 116 #define MPTCP_FALLBACK_DONE 4 117 #define MPTCP_WORK_CLOSE_SUBFLOW 5 118 119 /* MPTCP socket release cb flags */ 120 #define MPTCP_PUSH_PENDING 1 121 #define MPTCP_CLEAN_UNA 2 122 #define MPTCP_ERROR_REPORT 3 123 #define MPTCP_RETRANSMIT 4 124 #define MPTCP_FLUSH_JOIN_LIST 5 125 #define MPTCP_CONNECTED 6 126 #define MPTCP_RESET_SCHEDULER 7 127 128 struct mptcp_skb_cb { 129 u64 map_seq; 130 u64 end_seq; 131 u32 offset; 132 u8 has_rxtstamp:1; 133 }; 134 135 #define MPTCP_SKB_CB(__skb) ((struct mptcp_skb_cb *)&((__skb)->cb[0])) 136 137 static inline bool before64(__u64 seq1, __u64 seq2) 138 { 139 return (__s64)(seq1 - seq2) < 0; 140 } 141 142 #define after64(seq2, seq1) before64(seq1, seq2) 143 144 struct mptcp_options_received { 145 u64 sndr_key; 146 u64 rcvr_key; 147 u64 data_ack; 148 u64 data_seq; 149 u32 subflow_seq; 150 u16 data_len; 151 __sum16 csum; 152 u16 suboptions; 153 u32 token; 154 u32 nonce; 155 u16 use_map:1, 156 dsn64:1, 157 data_fin:1, 158 use_ack:1, 159 ack64:1, 160 mpc_map:1, 161 reset_reason:4, 162 reset_transient:1, 163 echo:1, 164 backup:1, 165 deny_join_id0:1, 166 __unused:2; 167 u8 join_id; 168 u64 thmac; 169 u8 hmac[MPTCPOPT_HMAC_LEN]; 170 struct mptcp_addr_info addr; 171 struct mptcp_rm_list rm_list; 172 u64 ahmac; 173 u64 fail_seq; 174 }; 175 176 static inline __be32 mptcp_option(u8 subopt, u8 len, u8 nib, u8 field) 177 { 178 return htonl((TCPOPT_MPTCP << 24) | (len << 16) | (subopt << 12) | 179 ((nib & 0xF) << 8) | field); 180 } 181 182 enum mptcp_pm_status { 183 MPTCP_PM_ADD_ADDR_RECEIVED, 184 MPTCP_PM_ADD_ADDR_SEND_ACK, 185 MPTCP_PM_RM_ADDR_RECEIVED, 186 MPTCP_PM_ESTABLISHED, 187 MPTCP_PM_SUBFLOW_ESTABLISHED, 188 MPTCP_PM_ALREADY_ESTABLISHED, /* persistent status, set after ESTABLISHED event */ 189 MPTCP_PM_MPC_ENDPOINT_ACCOUNTED /* persistent status, set after MPC local address is 190 * accounted int id_avail_bitmap 191 */ 192 }; 193 194 enum mptcp_pm_type { 195 MPTCP_PM_TYPE_KERNEL = 0, 196 MPTCP_PM_TYPE_USERSPACE, 197 198 __MPTCP_PM_TYPE_NR, 199 __MPTCP_PM_TYPE_MAX = __MPTCP_PM_TYPE_NR - 1, 200 }; 201 202 /* Status bits below MPTCP_PM_ALREADY_ESTABLISHED need pm worker actions */ 203 #define MPTCP_PM_WORK_MASK ((1 << MPTCP_PM_ALREADY_ESTABLISHED) - 1) 204 205 enum mptcp_addr_signal_status { 206 MPTCP_ADD_ADDR_SIGNAL, 207 MPTCP_ADD_ADDR_ECHO, 208 MPTCP_RM_ADDR_SIGNAL, 209 }; 210 211 /* max value of mptcp_addr_info.id */ 212 #define MPTCP_PM_MAX_ADDR_ID U8_MAX 213 214 struct mptcp_pm_data { 215 struct mptcp_addr_info local; 216 struct mptcp_addr_info remote; 217 struct list_head anno_list; 218 struct list_head userspace_pm_local_addr_list; 219 220 spinlock_t lock; /*protects the whole PM data */ 221 222 u8 addr_signal; 223 bool server_side; 224 bool work_pending; 225 bool accept_addr; 226 bool accept_subflow; 227 bool remote_deny_join_id0; 228 u8 add_addr_signaled; 229 u8 add_addr_accepted; 230 u8 local_addr_used; 231 u8 pm_type; 232 u8 subflows; 233 u8 status; 234 DECLARE_BITMAP(id_avail_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); 235 struct mptcp_rm_list rm_list_tx; 236 struct mptcp_rm_list rm_list_rx; 237 }; 238 239 struct mptcp_pm_addr_entry { 240 struct list_head list; 241 struct mptcp_addr_info addr; 242 u8 flags; 243 int ifindex; 244 struct socket *lsk; 245 }; 246 247 struct mptcp_data_frag { 248 struct list_head list; 249 u64 data_seq; 250 u16 data_len; 251 u16 offset; 252 u16 overhead; 253 u16 already_sent; 254 struct page *page; 255 }; 256 257 /* MPTCP connection sock */ 258 struct mptcp_sock { 259 /* inet_connection_sock must be the first member */ 260 struct inet_connection_sock sk; 261 u64 local_key; 262 u64 remote_key; 263 u64 write_seq; 264 u64 bytes_sent; 265 u64 snd_nxt; 266 u64 bytes_received; 267 u64 ack_seq; 268 atomic64_t rcv_wnd_sent; 269 u64 rcv_data_fin_seq; 270 u64 bytes_retrans; 271 int rmem_fwd_alloc; 272 struct sock *last_snd; 273 int snd_burst; 274 int old_wspace; 275 u64 recovery_snd_nxt; /* in recovery mode accept up to this seq; 276 * recovery related fields are under data_lock 277 * protection 278 */ 279 u64 bytes_acked; 280 u64 snd_una; 281 u64 wnd_end; 282 unsigned long timer_ival; 283 u32 token; 284 int rmem_released; 285 unsigned long flags; 286 unsigned long cb_flags; 287 unsigned long push_pending; 288 bool recovery; /* closing subflow write queue reinjected */ 289 bool can_ack; 290 bool fully_established; 291 bool rcv_data_fin; 292 bool snd_data_fin_enable; 293 bool rcv_fastclose; 294 bool use_64bit_ack; /* Set when we received a 64-bit DSN */ 295 bool csum_enabled; 296 bool allow_infinite_fallback; 297 u8 mpc_endpoint_id; 298 u8 recvmsg_inq:1, 299 cork:1, 300 nodelay:1, 301 fastopening:1, 302 in_accept_queue:1; 303 struct work_struct work; 304 struct sk_buff *ooo_last_skb; 305 struct rb_root out_of_order_queue; 306 struct sk_buff_head receive_queue; 307 struct list_head conn_list; 308 struct list_head rtx_queue; 309 struct mptcp_data_frag *first_pending; 310 struct list_head join_list; 311 struct socket *subflow; /* outgoing connect/listener/!mp_capable 312 * The mptcp ops can safely dereference, using suitable 313 * ONCE annotation, the subflow outside the socket 314 * lock as such sock is freed after close(). 315 */ 316 struct sock *first; 317 struct mptcp_pm_data pm; 318 struct { 319 u32 space; /* bytes copied in last measurement window */ 320 u32 copied; /* bytes copied in this measurement window */ 321 u64 time; /* start time of measurement window */ 322 u64 rtt_us; /* last maximum rtt of subflows */ 323 } rcvq_space; 324 325 u32 subflow_id; 326 u32 setsockopt_seq; 327 char ca_name[TCP_CA_NAME_MAX]; 328 }; 329 330 #define mptcp_data_lock(sk) spin_lock_bh(&(sk)->sk_lock.slock) 331 #define mptcp_data_unlock(sk) spin_unlock_bh(&(sk)->sk_lock.slock) 332 333 #define mptcp_for_each_subflow(__msk, __subflow) \ 334 list_for_each_entry(__subflow, &((__msk)->conn_list), node) 335 #define mptcp_for_each_subflow_safe(__msk, __subflow, __tmp) \ 336 list_for_each_entry_safe(__subflow, __tmp, &((__msk)->conn_list), node) 337 338 static inline void msk_owned_by_me(const struct mptcp_sock *msk) 339 { 340 sock_owned_by_me((const struct sock *)msk); 341 } 342 343 #define mptcp_sk(ptr) container_of_const(ptr, struct mptcp_sock, sk.icsk_inet.sk) 344 345 /* the msk socket don't use the backlog, also account for the bulk 346 * free memory 347 */ 348 static inline int __mptcp_rmem(const struct sock *sk) 349 { 350 return atomic_read(&sk->sk_rmem_alloc) - READ_ONCE(mptcp_sk(sk)->rmem_released); 351 } 352 353 static inline int __mptcp_space(const struct sock *sk) 354 { 355 return tcp_win_from_space(sk, READ_ONCE(sk->sk_rcvbuf) - __mptcp_rmem(sk)); 356 } 357 358 static inline struct mptcp_data_frag *mptcp_send_head(const struct sock *sk) 359 { 360 const struct mptcp_sock *msk = mptcp_sk(sk); 361 362 return READ_ONCE(msk->first_pending); 363 } 364 365 static inline struct mptcp_data_frag *mptcp_send_next(struct sock *sk) 366 { 367 struct mptcp_sock *msk = mptcp_sk(sk); 368 struct mptcp_data_frag *cur; 369 370 cur = msk->first_pending; 371 return list_is_last(&cur->list, &msk->rtx_queue) ? NULL : 372 list_next_entry(cur, list); 373 } 374 375 static inline struct mptcp_data_frag *mptcp_pending_tail(const struct sock *sk) 376 { 377 const struct mptcp_sock *msk = mptcp_sk(sk); 378 379 if (!msk->first_pending) 380 return NULL; 381 382 if (WARN_ON_ONCE(list_empty(&msk->rtx_queue))) 383 return NULL; 384 385 return list_last_entry(&msk->rtx_queue, struct mptcp_data_frag, list); 386 } 387 388 static inline struct mptcp_data_frag *mptcp_rtx_head(struct sock *sk) 389 { 390 struct mptcp_sock *msk = mptcp_sk(sk); 391 392 if (msk->snd_una == READ_ONCE(msk->snd_nxt)) 393 return NULL; 394 395 return list_first_entry_or_null(&msk->rtx_queue, struct mptcp_data_frag, list); 396 } 397 398 struct csum_pseudo_header { 399 __be64 data_seq; 400 __be32 subflow_seq; 401 __be16 data_len; 402 __sum16 csum; 403 }; 404 405 struct mptcp_subflow_request_sock { 406 struct tcp_request_sock sk; 407 u16 mp_capable : 1, 408 mp_join : 1, 409 backup : 1, 410 csum_reqd : 1, 411 allow_join_id0 : 1; 412 u8 local_id; 413 u8 remote_id; 414 u64 local_key; 415 u64 idsn; 416 u32 token; 417 u32 ssn_offset; 418 u64 thmac; 419 u32 local_nonce; 420 u32 remote_nonce; 421 struct mptcp_sock *msk; 422 struct hlist_nulls_node token_node; 423 }; 424 425 static inline struct mptcp_subflow_request_sock * 426 mptcp_subflow_rsk(const struct request_sock *rsk) 427 { 428 return (struct mptcp_subflow_request_sock *)rsk; 429 } 430 431 enum mptcp_data_avail { 432 MPTCP_SUBFLOW_NODATA, 433 MPTCP_SUBFLOW_DATA_AVAIL, 434 }; 435 436 struct mptcp_delegated_action { 437 struct napi_struct napi; 438 struct list_head head; 439 }; 440 441 DECLARE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions); 442 443 #define MPTCP_DELEGATE_SEND 0 444 #define MPTCP_DELEGATE_ACK 1 445 446 /* MPTCP subflow context */ 447 struct mptcp_subflow_context { 448 struct list_head node;/* conn_list of subflows */ 449 450 struct_group(reset, 451 452 unsigned long avg_pacing_rate; /* protected by msk socket lock */ 453 u64 local_key; 454 u64 remote_key; 455 u64 idsn; 456 u64 map_seq; 457 u32 snd_isn; 458 u32 token; 459 u32 rel_write_seq; 460 u32 map_subflow_seq; 461 u32 ssn_offset; 462 u32 map_data_len; 463 __wsum map_data_csum; 464 u32 map_csum_len; 465 u32 request_mptcp : 1, /* send MP_CAPABLE */ 466 request_join : 1, /* send MP_JOIN */ 467 request_bkup : 1, 468 mp_capable : 1, /* remote is MPTCP capable */ 469 mp_join : 1, /* remote is JOINing */ 470 fully_established : 1, /* path validated */ 471 pm_notified : 1, /* PM hook called for established status */ 472 conn_finished : 1, 473 map_valid : 1, 474 map_csum_reqd : 1, 475 map_data_fin : 1, 476 mpc_map : 1, 477 backup : 1, 478 send_mp_prio : 1, 479 send_mp_fail : 1, 480 send_fastclose : 1, 481 send_infinite_map : 1, 482 remote_key_valid : 1, /* received the peer key from */ 483 disposable : 1, /* ctx can be free at ulp release time */ 484 stale : 1, /* unable to snd/rcv data, do not use for xmit */ 485 local_id_valid : 1, /* local_id is correctly initialized */ 486 valid_csum_seen : 1, /* at least one csum validated */ 487 is_mptfo : 1, /* subflow is doing TFO */ 488 __unused : 9; 489 enum mptcp_data_avail data_avail; 490 u32 remote_nonce; 491 u64 thmac; 492 u32 local_nonce; 493 u32 remote_token; 494 union { 495 u8 hmac[MPTCPOPT_HMAC_LEN]; /* MPJ subflow only */ 496 u64 iasn; /* initial ack sequence number, MPC subflows only */ 497 }; 498 u8 local_id; 499 u8 remote_id; 500 u8 reset_seen:1; 501 u8 reset_transient:1; 502 u8 reset_reason:4; 503 u8 stale_count; 504 505 u32 subflow_id; 506 507 long delegated_status; 508 unsigned long fail_tout; 509 510 ); 511 512 struct list_head delegated_node; /* link into delegated_action, protected by local BH */ 513 514 u32 setsockopt_seq; 515 u32 stale_rcv_tstamp; 516 517 struct sock *tcp_sock; /* tcp sk backpointer */ 518 struct sock *conn; /* parent mptcp_sock */ 519 const struct inet_connection_sock_af_ops *icsk_af_ops; 520 void (*tcp_state_change)(struct sock *sk); 521 void (*tcp_error_report)(struct sock *sk); 522 523 struct rcu_head rcu; 524 }; 525 526 static inline struct mptcp_subflow_context * 527 mptcp_subflow_ctx(const struct sock *sk) 528 { 529 struct inet_connection_sock *icsk = inet_csk(sk); 530 531 /* Use RCU on icsk_ulp_data only for sock diag code */ 532 return (__force struct mptcp_subflow_context *)icsk->icsk_ulp_data; 533 } 534 535 static inline struct sock * 536 mptcp_subflow_tcp_sock(const struct mptcp_subflow_context *subflow) 537 { 538 return subflow->tcp_sock; 539 } 540 541 static inline void 542 mptcp_subflow_ctx_reset(struct mptcp_subflow_context *subflow) 543 { 544 memset(&subflow->reset, 0, sizeof(subflow->reset)); 545 subflow->request_mptcp = 1; 546 } 547 548 static inline u64 549 mptcp_subflow_get_map_offset(const struct mptcp_subflow_context *subflow) 550 { 551 return tcp_sk(mptcp_subflow_tcp_sock(subflow))->copied_seq - 552 subflow->ssn_offset - 553 subflow->map_subflow_seq; 554 } 555 556 static inline u64 557 mptcp_subflow_get_mapped_dsn(const struct mptcp_subflow_context *subflow) 558 { 559 return subflow->map_seq + mptcp_subflow_get_map_offset(subflow); 560 } 561 562 void mptcp_subflow_process_delegated(struct sock *ssk); 563 564 static inline void mptcp_subflow_delegate(struct mptcp_subflow_context *subflow, int action) 565 { 566 struct mptcp_delegated_action *delegated; 567 bool schedule; 568 569 /* the caller held the subflow bh socket lock */ 570 lockdep_assert_in_softirq(); 571 572 /* The implied barrier pairs with mptcp_subflow_delegated_done(), and 573 * ensures the below list check sees list updates done prior to status 574 * bit changes 575 */ 576 if (!test_and_set_bit(action, &subflow->delegated_status)) { 577 /* still on delegated list from previous scheduling */ 578 if (!list_empty(&subflow->delegated_node)) 579 return; 580 581 delegated = this_cpu_ptr(&mptcp_delegated_actions); 582 schedule = list_empty(&delegated->head); 583 list_add_tail(&subflow->delegated_node, &delegated->head); 584 sock_hold(mptcp_subflow_tcp_sock(subflow)); 585 if (schedule) 586 napi_schedule(&delegated->napi); 587 } 588 } 589 590 static inline struct mptcp_subflow_context * 591 mptcp_subflow_delegated_next(struct mptcp_delegated_action *delegated) 592 { 593 struct mptcp_subflow_context *ret; 594 595 if (list_empty(&delegated->head)) 596 return NULL; 597 598 ret = list_first_entry(&delegated->head, struct mptcp_subflow_context, delegated_node); 599 list_del_init(&ret->delegated_node); 600 return ret; 601 } 602 603 static inline bool mptcp_subflow_has_delegated_action(const struct mptcp_subflow_context *subflow) 604 { 605 return !!READ_ONCE(subflow->delegated_status); 606 } 607 608 static inline void mptcp_subflow_delegated_done(struct mptcp_subflow_context *subflow, int action) 609 { 610 /* pairs with mptcp_subflow_delegate, ensures delegate_node is updated before 611 * touching the status bit 612 */ 613 smp_wmb(); 614 clear_bit(action, &subflow->delegated_status); 615 } 616 617 int mptcp_is_enabled(const struct net *net); 618 unsigned int mptcp_get_add_addr_timeout(const struct net *net); 619 int mptcp_is_checksum_enabled(const struct net *net); 620 int mptcp_allow_join_id0(const struct net *net); 621 unsigned int mptcp_stale_loss_cnt(const struct net *net); 622 int mptcp_get_pm_type(const struct net *net); 623 void mptcp_subflow_fully_established(struct mptcp_subflow_context *subflow, 624 const struct mptcp_options_received *mp_opt); 625 bool __mptcp_retransmit_pending_data(struct sock *sk); 626 void mptcp_check_and_set_pending(struct sock *sk); 627 void __mptcp_push_pending(struct sock *sk, unsigned int flags); 628 bool mptcp_subflow_data_available(struct sock *sk); 629 void __init mptcp_subflow_init(void); 630 void mptcp_subflow_shutdown(struct sock *sk, struct sock *ssk, int how); 631 void mptcp_close_ssk(struct sock *sk, struct sock *ssk, 632 struct mptcp_subflow_context *subflow); 633 void __mptcp_subflow_send_ack(struct sock *ssk); 634 void mptcp_subflow_reset(struct sock *ssk); 635 void mptcp_subflow_queue_clean(struct sock *sk, struct sock *ssk); 636 void mptcp_sock_graft(struct sock *sk, struct socket *parent); 637 struct socket *__mptcp_nmpc_socket(struct mptcp_sock *msk); 638 bool __mptcp_close(struct sock *sk, long timeout); 639 void mptcp_cancel_work(struct sock *sk); 640 void __mptcp_unaccepted_force_close(struct sock *sk); 641 void mptcp_set_owner_r(struct sk_buff *skb, struct sock *sk); 642 643 bool mptcp_addresses_equal(const struct mptcp_addr_info *a, 644 const struct mptcp_addr_info *b, bool use_port); 645 void mptcp_local_address(const struct sock_common *skc, struct mptcp_addr_info *addr); 646 647 /* called with sk socket lock held */ 648 int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_addr_info *loc, 649 const struct mptcp_addr_info *remote); 650 int mptcp_subflow_create_socket(struct sock *sk, unsigned short family, 651 struct socket **new_sock); 652 void mptcp_info2sockaddr(const struct mptcp_addr_info *info, 653 struct sockaddr_storage *addr, 654 unsigned short family); 655 656 static inline bool __tcp_can_send(const struct sock *ssk) 657 { 658 /* only send if our side has not closed yet */ 659 return ((1 << inet_sk_state_load(ssk)) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)); 660 } 661 662 static inline bool __mptcp_subflow_active(struct mptcp_subflow_context *subflow) 663 { 664 /* can't send if JOIN hasn't completed yet (i.e. is usable for mptcp) */ 665 if (subflow->request_join && !subflow->fully_established) 666 return false; 667 668 return __tcp_can_send(mptcp_subflow_tcp_sock(subflow)); 669 } 670 671 void mptcp_subflow_set_active(struct mptcp_subflow_context *subflow); 672 673 bool mptcp_subflow_active(struct mptcp_subflow_context *subflow); 674 675 void mptcp_subflow_drop_ctx(struct sock *ssk); 676 677 static inline void mptcp_subflow_tcp_fallback(struct sock *sk, 678 struct mptcp_subflow_context *ctx) 679 { 680 sk->sk_data_ready = sock_def_readable; 681 sk->sk_state_change = ctx->tcp_state_change; 682 sk->sk_write_space = sk_stream_write_space; 683 sk->sk_error_report = ctx->tcp_error_report; 684 685 inet_csk(sk)->icsk_af_ops = ctx->icsk_af_ops; 686 } 687 688 void __init mptcp_proto_init(void); 689 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 690 int __init mptcp_proto_v6_init(void); 691 #endif 692 693 struct sock *mptcp_sk_clone_init(const struct sock *sk, 694 const struct mptcp_options_received *mp_opt, 695 struct sock *ssk, 696 struct request_sock *req); 697 void mptcp_get_options(const struct sk_buff *skb, 698 struct mptcp_options_received *mp_opt); 699 700 void mptcp_finish_connect(struct sock *sk); 701 void __mptcp_set_connected(struct sock *sk); 702 void mptcp_reset_timeout(struct mptcp_sock *msk, unsigned long fail_tout); 703 static inline bool mptcp_is_fully_established(struct sock *sk) 704 { 705 return inet_sk_state_load(sk) == TCP_ESTABLISHED && 706 READ_ONCE(mptcp_sk(sk)->fully_established); 707 } 708 void mptcp_rcv_space_init(struct mptcp_sock *msk, const struct sock *ssk); 709 void mptcp_data_ready(struct sock *sk, struct sock *ssk); 710 bool mptcp_finish_join(struct sock *sk); 711 bool mptcp_schedule_work(struct sock *sk); 712 int mptcp_setsockopt(struct sock *sk, int level, int optname, 713 sockptr_t optval, unsigned int optlen); 714 int mptcp_getsockopt(struct sock *sk, int level, int optname, 715 char __user *optval, int __user *option); 716 717 u64 __mptcp_expand_seq(u64 old_seq, u64 cur_seq); 718 static inline u64 mptcp_expand_seq(u64 old_seq, u64 cur_seq, bool use_64bit) 719 { 720 if (use_64bit) 721 return cur_seq; 722 723 return __mptcp_expand_seq(old_seq, cur_seq); 724 } 725 void __mptcp_check_push(struct sock *sk, struct sock *ssk); 726 void __mptcp_data_acked(struct sock *sk); 727 void __mptcp_error_report(struct sock *sk); 728 bool mptcp_update_rcv_data_fin(struct mptcp_sock *msk, u64 data_fin_seq, bool use_64bit); 729 static inline bool mptcp_data_fin_enabled(const struct mptcp_sock *msk) 730 { 731 return READ_ONCE(msk->snd_data_fin_enable) && 732 READ_ONCE(msk->write_seq) == READ_ONCE(msk->snd_nxt); 733 } 734 735 static inline bool mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk) 736 { 737 if ((sk->sk_userlocks & SOCK_SNDBUF_LOCK) || ssk->sk_sndbuf <= READ_ONCE(sk->sk_sndbuf)) 738 return false; 739 740 WRITE_ONCE(sk->sk_sndbuf, ssk->sk_sndbuf); 741 return true; 742 } 743 744 static inline void mptcp_write_space(struct sock *sk) 745 { 746 if (sk_stream_is_writeable(sk)) { 747 /* pairs with memory barrier in mptcp_poll */ 748 smp_mb(); 749 if (test_and_clear_bit(MPTCP_NOSPACE, &mptcp_sk(sk)->flags)) 750 sk_stream_write_space(sk); 751 } 752 } 753 754 void mptcp_destroy_common(struct mptcp_sock *msk, unsigned int flags); 755 756 #define MPTCP_TOKEN_MAX_RETRIES 4 757 758 void __init mptcp_token_init(void); 759 static inline void mptcp_token_init_request(struct request_sock *req) 760 { 761 mptcp_subflow_rsk(req)->token_node.pprev = NULL; 762 } 763 764 int mptcp_token_new_request(struct request_sock *req); 765 void mptcp_token_destroy_request(struct request_sock *req); 766 int mptcp_token_new_connect(struct sock *ssk); 767 void mptcp_token_accept(struct mptcp_subflow_request_sock *r, 768 struct mptcp_sock *msk); 769 bool mptcp_token_exists(u32 token); 770 struct mptcp_sock *mptcp_token_get_sock(struct net *net, u32 token); 771 struct mptcp_sock *mptcp_token_iter_next(const struct net *net, long *s_slot, 772 long *s_num); 773 void mptcp_token_destroy(struct mptcp_sock *msk); 774 775 void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn); 776 777 void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u8 *msg, int len, void *hmac); 778 __sum16 __mptcp_make_csum(u64 data_seq, u32 subflow_seq, u16 data_len, __wsum sum); 779 780 void __init mptcp_pm_init(void); 781 void mptcp_pm_data_init(struct mptcp_sock *msk); 782 void mptcp_pm_data_reset(struct mptcp_sock *msk); 783 int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info, 784 struct mptcp_addr_info *addr); 785 int mptcp_pm_parse_entry(struct nlattr *attr, struct genl_info *info, 786 bool require_family, 787 struct mptcp_pm_addr_entry *entry); 788 bool mptcp_pm_addr_families_match(const struct sock *sk, 789 const struct mptcp_addr_info *loc, 790 const struct mptcp_addr_info *rem); 791 void mptcp_pm_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); 792 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); 793 void mptcp_pm_new_connection(struct mptcp_sock *msk, const struct sock *ssk, int server_side); 794 void mptcp_pm_fully_established(struct mptcp_sock *msk, const struct sock *ssk); 795 bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk); 796 void mptcp_pm_connection_closed(struct mptcp_sock *msk); 797 void mptcp_pm_subflow_established(struct mptcp_sock *msk); 798 bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk); 799 void mptcp_pm_subflow_check_next(struct mptcp_sock *msk, const struct sock *ssk, 800 const struct mptcp_subflow_context *subflow); 801 void mptcp_pm_add_addr_received(const struct sock *ssk, 802 const struct mptcp_addr_info *addr); 803 void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk, 804 const struct mptcp_addr_info *addr); 805 void mptcp_pm_add_addr_send_ack(struct mptcp_sock *msk); 806 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk); 807 void mptcp_pm_rm_addr_received(struct mptcp_sock *msk, 808 const struct mptcp_rm_list *rm_list); 809 void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup); 810 void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq); 811 int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk, 812 struct mptcp_addr_info *addr, 813 struct mptcp_addr_info *rem, 814 u8 bkup); 815 bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk, 816 const struct mptcp_addr_info *addr); 817 void mptcp_pm_free_anno_list(struct mptcp_sock *msk); 818 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk); 819 struct mptcp_pm_add_entry * 820 mptcp_pm_del_add_timer(struct mptcp_sock *msk, 821 const struct mptcp_addr_info *addr, bool check_id); 822 struct mptcp_pm_add_entry * 823 mptcp_lookup_anno_list_by_saddr(const struct mptcp_sock *msk, 824 const struct mptcp_addr_info *addr); 825 int mptcp_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, 826 unsigned int id, 827 u8 *flags, int *ifindex); 828 int mptcp_pm_nl_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, unsigned int id, 829 u8 *flags, int *ifindex); 830 int mptcp_userspace_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, 831 unsigned int id, 832 u8 *flags, int *ifindex); 833 int mptcp_pm_set_flags(struct net *net, struct nlattr *token, 834 struct mptcp_pm_addr_entry *loc, 835 struct mptcp_pm_addr_entry *rem, u8 bkup); 836 int mptcp_pm_nl_set_flags(struct net *net, struct mptcp_pm_addr_entry *addr, u8 bkup); 837 int mptcp_userspace_pm_set_flags(struct net *net, struct nlattr *token, 838 struct mptcp_pm_addr_entry *loc, 839 struct mptcp_pm_addr_entry *rem, u8 bkup); 840 int mptcp_pm_announce_addr(struct mptcp_sock *msk, 841 const struct mptcp_addr_info *addr, 842 bool echo); 843 int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); 844 int mptcp_pm_remove_subflow(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); 845 void mptcp_pm_remove_addrs(struct mptcp_sock *msk, struct list_head *rm_list); 846 void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk, 847 struct list_head *rm_list); 848 849 void mptcp_free_local_addr_list(struct mptcp_sock *msk); 850 int mptcp_nl_cmd_announce(struct sk_buff *skb, struct genl_info *info); 851 int mptcp_nl_cmd_remove(struct sk_buff *skb, struct genl_info *info); 852 int mptcp_nl_cmd_sf_create(struct sk_buff *skb, struct genl_info *info); 853 int mptcp_nl_cmd_sf_destroy(struct sk_buff *skb, struct genl_info *info); 854 855 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk, 856 const struct sock *ssk, gfp_t gfp); 857 void mptcp_event_addr_announced(const struct sock *ssk, const struct mptcp_addr_info *info); 858 void mptcp_event_addr_removed(const struct mptcp_sock *msk, u8 id); 859 void mptcp_event_pm_listener(const struct sock *ssk, 860 enum mptcp_event_type event); 861 bool mptcp_userspace_pm_active(const struct mptcp_sock *msk); 862 863 void mptcp_fastopen_gen_msk_ackseq(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow, 864 const struct mptcp_options_received *mp_opt); 865 void mptcp_fastopen_subflow_synack_set_params(struct mptcp_subflow_context *subflow, 866 struct request_sock *req); 867 868 static inline bool mptcp_pm_should_add_signal(struct mptcp_sock *msk) 869 { 870 return READ_ONCE(msk->pm.addr_signal) & 871 (BIT(MPTCP_ADD_ADDR_SIGNAL) | BIT(MPTCP_ADD_ADDR_ECHO)); 872 } 873 874 static inline bool mptcp_pm_should_add_signal_addr(struct mptcp_sock *msk) 875 { 876 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_SIGNAL); 877 } 878 879 static inline bool mptcp_pm_should_add_signal_echo(struct mptcp_sock *msk) 880 { 881 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_ECHO); 882 } 883 884 static inline bool mptcp_pm_should_rm_signal(struct mptcp_sock *msk) 885 { 886 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_RM_ADDR_SIGNAL); 887 } 888 889 static inline bool mptcp_pm_is_userspace(const struct mptcp_sock *msk) 890 { 891 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_USERSPACE; 892 } 893 894 static inline bool mptcp_pm_is_kernel(const struct mptcp_sock *msk) 895 { 896 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_KERNEL; 897 } 898 899 static inline unsigned int mptcp_add_addr_len(int family, bool echo, bool port) 900 { 901 u8 len = TCPOLEN_MPTCP_ADD_ADDR_BASE; 902 903 if (family == AF_INET6) 904 len = TCPOLEN_MPTCP_ADD_ADDR6_BASE; 905 if (!echo) 906 len += MPTCPOPT_THMAC_LEN; 907 /* account for 2 trailing 'nop' options */ 908 if (port) 909 len += TCPOLEN_MPTCP_PORT_LEN + TCPOLEN_MPTCP_PORT_ALIGN; 910 911 return len; 912 } 913 914 static inline int mptcp_rm_addr_len(const struct mptcp_rm_list *rm_list) 915 { 916 if (rm_list->nr == 0 || rm_list->nr > MPTCP_RM_IDS_MAX) 917 return -EINVAL; 918 919 return TCPOLEN_MPTCP_RM_ADDR_BASE + roundup(rm_list->nr - 1, 4) + 1; 920 } 921 922 bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, const struct sk_buff *skb, 923 unsigned int opt_size, unsigned int remaining, 924 struct mptcp_addr_info *addr, bool *echo, 925 bool *drop_other_suboptions); 926 bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining, 927 struct mptcp_rm_list *rm_list); 928 int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc); 929 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc); 930 int mptcp_userspace_pm_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc); 931 932 void __init mptcp_pm_nl_init(void); 933 void mptcp_pm_nl_work(struct mptcp_sock *msk); 934 void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk, 935 const struct mptcp_rm_list *rm_list); 936 unsigned int mptcp_pm_get_add_addr_signal_max(const struct mptcp_sock *msk); 937 unsigned int mptcp_pm_get_add_addr_accept_max(const struct mptcp_sock *msk); 938 unsigned int mptcp_pm_get_subflows_max(const struct mptcp_sock *msk); 939 unsigned int mptcp_pm_get_local_addr_max(const struct mptcp_sock *msk); 940 941 /* called under PM lock */ 942 static inline void __mptcp_pm_close_subflow(struct mptcp_sock *msk) 943 { 944 if (--msk->pm.subflows < mptcp_pm_get_subflows_max(msk)) 945 WRITE_ONCE(msk->pm.accept_subflow, true); 946 } 947 948 static inline void mptcp_pm_close_subflow(struct mptcp_sock *msk) 949 { 950 spin_lock_bh(&msk->pm.lock); 951 __mptcp_pm_close_subflow(msk); 952 spin_unlock_bh(&msk->pm.lock); 953 } 954 955 void mptcp_sockopt_sync(struct mptcp_sock *msk, struct sock *ssk); 956 void mptcp_sockopt_sync_locked(struct mptcp_sock *msk, struct sock *ssk); 957 958 static inline struct mptcp_ext *mptcp_get_ext(const struct sk_buff *skb) 959 { 960 return (struct mptcp_ext *)skb_ext_find(skb, SKB_EXT_MPTCP); 961 } 962 963 void mptcp_diag_subflow_init(struct tcp_ulp_ops *ops); 964 965 static inline bool __mptcp_check_fallback(const struct mptcp_sock *msk) 966 { 967 return test_bit(MPTCP_FALLBACK_DONE, &msk->flags); 968 } 969 970 static inline bool mptcp_check_fallback(const struct sock *sk) 971 { 972 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 973 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 974 975 return __mptcp_check_fallback(msk); 976 } 977 978 static inline void __mptcp_do_fallback(struct mptcp_sock *msk) 979 { 980 if (test_bit(MPTCP_FALLBACK_DONE, &msk->flags)) { 981 pr_debug("TCP fallback already done (msk=%p)", msk); 982 return; 983 } 984 set_bit(MPTCP_FALLBACK_DONE, &msk->flags); 985 } 986 987 static inline void mptcp_do_fallback(struct sock *ssk) 988 { 989 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 990 struct sock *sk = subflow->conn; 991 struct mptcp_sock *msk; 992 993 msk = mptcp_sk(sk); 994 __mptcp_do_fallback(msk); 995 if (READ_ONCE(msk->snd_data_fin_enable) && !(ssk->sk_shutdown & SEND_SHUTDOWN)) { 996 gfp_t saved_allocation = ssk->sk_allocation; 997 998 /* we are in a atomic (BH) scope, override ssk default for data 999 * fin allocation 1000 */ 1001 ssk->sk_allocation = GFP_ATOMIC; 1002 ssk->sk_shutdown |= SEND_SHUTDOWN; 1003 tcp_shutdown(ssk, SEND_SHUTDOWN); 1004 ssk->sk_allocation = saved_allocation; 1005 } 1006 } 1007 1008 #define pr_fallback(a) pr_debug("%s:fallback to TCP (msk=%p)", __func__, a) 1009 1010 static inline bool mptcp_check_infinite_map(struct sk_buff *skb) 1011 { 1012 struct mptcp_ext *mpext; 1013 1014 mpext = skb ? mptcp_get_ext(skb) : NULL; 1015 if (mpext && mpext->infinite_map) 1016 return true; 1017 1018 return false; 1019 } 1020 1021 static inline bool is_active_ssk(struct mptcp_subflow_context *subflow) 1022 { 1023 return (subflow->request_mptcp || subflow->request_join); 1024 } 1025 1026 static inline bool subflow_simultaneous_connect(struct sock *sk) 1027 { 1028 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 1029 1030 return sk->sk_state == TCP_ESTABLISHED && 1031 is_active_ssk(subflow) && 1032 !subflow->conn_finished; 1033 } 1034 1035 #ifdef CONFIG_SYN_COOKIES 1036 void subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 1037 struct sk_buff *skb); 1038 bool mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 1039 struct sk_buff *skb); 1040 void __init mptcp_join_cookie_init(void); 1041 #else 1042 static inline void 1043 subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 1044 struct sk_buff *skb) {} 1045 static inline bool 1046 mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 1047 struct sk_buff *skb) 1048 { 1049 return false; 1050 } 1051 1052 static inline void mptcp_join_cookie_init(void) {} 1053 #endif 1054 1055 #endif /* __MPTCP_PROTOCOL_H */ 1056