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 free_first:1; 304 struct work_struct work; 305 struct sk_buff *ooo_last_skb; 306 struct rb_root out_of_order_queue; 307 struct sk_buff_head receive_queue; 308 struct list_head conn_list; 309 struct list_head rtx_queue; 310 struct mptcp_data_frag *first_pending; 311 struct list_head join_list; 312 struct sock *first; /* 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 mptcp_pm_data pm; 317 struct { 318 u32 space; /* bytes copied in last measurement window */ 319 u32 copied; /* bytes copied in this measurement window */ 320 u64 time; /* start time of measurement window */ 321 u64 rtt_us; /* last maximum rtt of subflows */ 322 } rcvq_space; 323 u8 scaling_ratio; 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_win_from_space(const struct sock *sk, int space) 354 { 355 return __tcp_win_from_space(mptcp_sk(sk)->scaling_ratio, space); 356 } 357 358 static inline int __mptcp_space(const struct sock *sk) 359 { 360 return mptcp_win_from_space(sk, READ_ONCE(sk->sk_rcvbuf) - __mptcp_rmem(sk)); 361 } 362 363 static inline struct mptcp_data_frag *mptcp_send_head(const struct sock *sk) 364 { 365 const struct mptcp_sock *msk = mptcp_sk(sk); 366 367 return READ_ONCE(msk->first_pending); 368 } 369 370 static inline struct mptcp_data_frag *mptcp_send_next(struct sock *sk) 371 { 372 struct mptcp_sock *msk = mptcp_sk(sk); 373 struct mptcp_data_frag *cur; 374 375 cur = msk->first_pending; 376 return list_is_last(&cur->list, &msk->rtx_queue) ? NULL : 377 list_next_entry(cur, list); 378 } 379 380 static inline struct mptcp_data_frag *mptcp_pending_tail(const struct sock *sk) 381 { 382 const struct mptcp_sock *msk = mptcp_sk(sk); 383 384 if (!msk->first_pending) 385 return NULL; 386 387 if (WARN_ON_ONCE(list_empty(&msk->rtx_queue))) 388 return NULL; 389 390 return list_last_entry(&msk->rtx_queue, struct mptcp_data_frag, list); 391 } 392 393 static inline struct mptcp_data_frag *mptcp_rtx_head(struct sock *sk) 394 { 395 struct mptcp_sock *msk = mptcp_sk(sk); 396 397 if (msk->snd_una == READ_ONCE(msk->snd_nxt)) 398 return NULL; 399 400 return list_first_entry_or_null(&msk->rtx_queue, struct mptcp_data_frag, list); 401 } 402 403 struct csum_pseudo_header { 404 __be64 data_seq; 405 __be32 subflow_seq; 406 __be16 data_len; 407 __sum16 csum; 408 }; 409 410 struct mptcp_subflow_request_sock { 411 struct tcp_request_sock sk; 412 u16 mp_capable : 1, 413 mp_join : 1, 414 backup : 1, 415 csum_reqd : 1, 416 allow_join_id0 : 1; 417 u8 local_id; 418 u8 remote_id; 419 u64 local_key; 420 u64 idsn; 421 u32 token; 422 u32 ssn_offset; 423 u64 thmac; 424 u32 local_nonce; 425 u32 remote_nonce; 426 struct mptcp_sock *msk; 427 struct hlist_nulls_node token_node; 428 }; 429 430 static inline struct mptcp_subflow_request_sock * 431 mptcp_subflow_rsk(const struct request_sock *rsk) 432 { 433 return (struct mptcp_subflow_request_sock *)rsk; 434 } 435 436 enum mptcp_data_avail { 437 MPTCP_SUBFLOW_NODATA, 438 MPTCP_SUBFLOW_DATA_AVAIL, 439 }; 440 441 struct mptcp_delegated_action { 442 struct napi_struct napi; 443 struct list_head head; 444 }; 445 446 DECLARE_PER_CPU(struct mptcp_delegated_action, mptcp_delegated_actions); 447 448 #define MPTCP_DELEGATE_SEND 0 449 #define MPTCP_DELEGATE_ACK 1 450 451 /* MPTCP subflow context */ 452 struct mptcp_subflow_context { 453 struct list_head node;/* conn_list of subflows */ 454 455 struct_group(reset, 456 457 unsigned long avg_pacing_rate; /* protected by msk socket lock */ 458 u64 local_key; 459 u64 remote_key; 460 u64 idsn; 461 u64 map_seq; 462 u32 snd_isn; 463 u32 token; 464 u32 rel_write_seq; 465 u32 map_subflow_seq; 466 u32 ssn_offset; 467 u32 map_data_len; 468 __wsum map_data_csum; 469 u32 map_csum_len; 470 u32 request_mptcp : 1, /* send MP_CAPABLE */ 471 request_join : 1, /* send MP_JOIN */ 472 request_bkup : 1, 473 mp_capable : 1, /* remote is MPTCP capable */ 474 mp_join : 1, /* remote is JOINing */ 475 fully_established : 1, /* path validated */ 476 pm_notified : 1, /* PM hook called for established status */ 477 conn_finished : 1, 478 map_valid : 1, 479 map_csum_reqd : 1, 480 map_data_fin : 1, 481 mpc_map : 1, 482 backup : 1, 483 send_mp_prio : 1, 484 send_mp_fail : 1, 485 send_fastclose : 1, 486 send_infinite_map : 1, 487 remote_key_valid : 1, /* received the peer key from */ 488 disposable : 1, /* ctx can be free at ulp release time */ 489 stale : 1, /* unable to snd/rcv data, do not use for xmit */ 490 local_id_valid : 1, /* local_id is correctly initialized */ 491 valid_csum_seen : 1, /* at least one csum validated */ 492 is_mptfo : 1, /* subflow is doing TFO */ 493 __unused : 9; 494 enum mptcp_data_avail data_avail; 495 u32 remote_nonce; 496 u64 thmac; 497 u32 local_nonce; 498 u32 remote_token; 499 union { 500 u8 hmac[MPTCPOPT_HMAC_LEN]; /* MPJ subflow only */ 501 u64 iasn; /* initial ack sequence number, MPC subflows only */ 502 }; 503 u8 local_id; 504 u8 remote_id; 505 u8 reset_seen:1; 506 u8 reset_transient:1; 507 u8 reset_reason:4; 508 u8 stale_count; 509 510 u32 subflow_id; 511 512 long delegated_status; 513 unsigned long fail_tout; 514 515 ); 516 517 struct list_head delegated_node; /* link into delegated_action, protected by local BH */ 518 519 u32 setsockopt_seq; 520 u32 stale_rcv_tstamp; 521 522 struct sock *tcp_sock; /* tcp sk backpointer */ 523 struct sock *conn; /* parent mptcp_sock */ 524 const struct inet_connection_sock_af_ops *icsk_af_ops; 525 void (*tcp_state_change)(struct sock *sk); 526 void (*tcp_error_report)(struct sock *sk); 527 528 struct rcu_head rcu; 529 }; 530 531 static inline struct mptcp_subflow_context * 532 mptcp_subflow_ctx(const struct sock *sk) 533 { 534 struct inet_connection_sock *icsk = inet_csk(sk); 535 536 /* Use RCU on icsk_ulp_data only for sock diag code */ 537 return (__force struct mptcp_subflow_context *)icsk->icsk_ulp_data; 538 } 539 540 static inline struct sock * 541 mptcp_subflow_tcp_sock(const struct mptcp_subflow_context *subflow) 542 { 543 return subflow->tcp_sock; 544 } 545 546 static inline void 547 mptcp_subflow_ctx_reset(struct mptcp_subflow_context *subflow) 548 { 549 memset(&subflow->reset, 0, sizeof(subflow->reset)); 550 subflow->request_mptcp = 1; 551 } 552 553 static inline u64 554 mptcp_subflow_get_map_offset(const struct mptcp_subflow_context *subflow) 555 { 556 return tcp_sk(mptcp_subflow_tcp_sock(subflow))->copied_seq - 557 subflow->ssn_offset - 558 subflow->map_subflow_seq; 559 } 560 561 static inline u64 562 mptcp_subflow_get_mapped_dsn(const struct mptcp_subflow_context *subflow) 563 { 564 return subflow->map_seq + mptcp_subflow_get_map_offset(subflow); 565 } 566 567 void mptcp_subflow_process_delegated(struct sock *ssk); 568 569 static inline void mptcp_subflow_delegate(struct mptcp_subflow_context *subflow, int action) 570 { 571 struct mptcp_delegated_action *delegated; 572 bool schedule; 573 574 /* the caller held the subflow bh socket lock */ 575 lockdep_assert_in_softirq(); 576 577 /* The implied barrier pairs with mptcp_subflow_delegated_done(), and 578 * ensures the below list check sees list updates done prior to status 579 * bit changes 580 */ 581 if (!test_and_set_bit(action, &subflow->delegated_status)) { 582 /* still on delegated list from previous scheduling */ 583 if (!list_empty(&subflow->delegated_node)) 584 return; 585 586 delegated = this_cpu_ptr(&mptcp_delegated_actions); 587 schedule = list_empty(&delegated->head); 588 list_add_tail(&subflow->delegated_node, &delegated->head); 589 sock_hold(mptcp_subflow_tcp_sock(subflow)); 590 if (schedule) 591 napi_schedule(&delegated->napi); 592 } 593 } 594 595 static inline struct mptcp_subflow_context * 596 mptcp_subflow_delegated_next(struct mptcp_delegated_action *delegated) 597 { 598 struct mptcp_subflow_context *ret; 599 600 if (list_empty(&delegated->head)) 601 return NULL; 602 603 ret = list_first_entry(&delegated->head, struct mptcp_subflow_context, delegated_node); 604 list_del_init(&ret->delegated_node); 605 return ret; 606 } 607 608 static inline bool mptcp_subflow_has_delegated_action(const struct mptcp_subflow_context *subflow) 609 { 610 return !!READ_ONCE(subflow->delegated_status); 611 } 612 613 static inline void mptcp_subflow_delegated_done(struct mptcp_subflow_context *subflow, int action) 614 { 615 /* pairs with mptcp_subflow_delegate, ensures delegate_node is updated before 616 * touching the status bit 617 */ 618 smp_wmb(); 619 clear_bit(action, &subflow->delegated_status); 620 } 621 622 int mptcp_is_enabled(const struct net *net); 623 unsigned int mptcp_get_add_addr_timeout(const struct net *net); 624 int mptcp_is_checksum_enabled(const struct net *net); 625 int mptcp_allow_join_id0(const struct net *net); 626 unsigned int mptcp_stale_loss_cnt(const struct net *net); 627 int mptcp_get_pm_type(const struct net *net); 628 void mptcp_subflow_fully_established(struct mptcp_subflow_context *subflow, 629 const struct mptcp_options_received *mp_opt); 630 bool __mptcp_retransmit_pending_data(struct sock *sk); 631 void mptcp_check_and_set_pending(struct sock *sk); 632 void __mptcp_push_pending(struct sock *sk, unsigned int flags); 633 bool mptcp_subflow_data_available(struct sock *sk); 634 void __init mptcp_subflow_init(void); 635 void mptcp_subflow_shutdown(struct sock *sk, struct sock *ssk, int how); 636 void mptcp_close_ssk(struct sock *sk, struct sock *ssk, 637 struct mptcp_subflow_context *subflow); 638 void __mptcp_subflow_send_ack(struct sock *ssk); 639 void mptcp_subflow_reset(struct sock *ssk); 640 void mptcp_subflow_queue_clean(struct sock *sk, struct sock *ssk); 641 void mptcp_sock_graft(struct sock *sk, struct socket *parent); 642 struct sock *__mptcp_nmpc_sk(struct mptcp_sock *msk); 643 bool __mptcp_close(struct sock *sk, long timeout); 644 void mptcp_cancel_work(struct sock *sk); 645 void __mptcp_unaccepted_force_close(struct sock *sk); 646 void mptcp_set_owner_r(struct sk_buff *skb, struct sock *sk); 647 648 bool mptcp_addresses_equal(const struct mptcp_addr_info *a, 649 const struct mptcp_addr_info *b, bool use_port); 650 void mptcp_local_address(const struct sock_common *skc, struct mptcp_addr_info *addr); 651 652 /* called with sk socket lock held */ 653 int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_addr_info *loc, 654 const struct mptcp_addr_info *remote); 655 int mptcp_subflow_create_socket(struct sock *sk, unsigned short family, 656 struct socket **new_sock); 657 void mptcp_info2sockaddr(const struct mptcp_addr_info *info, 658 struct sockaddr_storage *addr, 659 unsigned short family); 660 661 static inline bool __tcp_can_send(const struct sock *ssk) 662 { 663 /* only send if our side has not closed yet */ 664 return ((1 << inet_sk_state_load(ssk)) & (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)); 665 } 666 667 static inline bool __mptcp_subflow_active(struct mptcp_subflow_context *subflow) 668 { 669 /* can't send if JOIN hasn't completed yet (i.e. is usable for mptcp) */ 670 if (subflow->request_join && !subflow->fully_established) 671 return false; 672 673 return __tcp_can_send(mptcp_subflow_tcp_sock(subflow)); 674 } 675 676 void mptcp_subflow_set_active(struct mptcp_subflow_context *subflow); 677 678 bool mptcp_subflow_active(struct mptcp_subflow_context *subflow); 679 680 void mptcp_subflow_drop_ctx(struct sock *ssk); 681 682 static inline void mptcp_subflow_tcp_fallback(struct sock *sk, 683 struct mptcp_subflow_context *ctx) 684 { 685 sk->sk_data_ready = sock_def_readable; 686 sk->sk_state_change = ctx->tcp_state_change; 687 sk->sk_write_space = sk_stream_write_space; 688 sk->sk_error_report = ctx->tcp_error_report; 689 690 inet_csk(sk)->icsk_af_ops = ctx->icsk_af_ops; 691 } 692 693 void __init mptcp_proto_init(void); 694 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 695 int __init mptcp_proto_v6_init(void); 696 #endif 697 698 struct sock *mptcp_sk_clone_init(const struct sock *sk, 699 const struct mptcp_options_received *mp_opt, 700 struct sock *ssk, 701 struct request_sock *req); 702 void mptcp_get_options(const struct sk_buff *skb, 703 struct mptcp_options_received *mp_opt); 704 705 void mptcp_finish_connect(struct sock *sk); 706 void __mptcp_set_connected(struct sock *sk); 707 void mptcp_reset_timeout(struct mptcp_sock *msk, unsigned long fail_tout); 708 static inline bool mptcp_is_fully_established(struct sock *sk) 709 { 710 return inet_sk_state_load(sk) == TCP_ESTABLISHED && 711 READ_ONCE(mptcp_sk(sk)->fully_established); 712 } 713 void mptcp_rcv_space_init(struct mptcp_sock *msk, const struct sock *ssk); 714 void mptcp_data_ready(struct sock *sk, struct sock *ssk); 715 bool mptcp_finish_join(struct sock *sk); 716 bool mptcp_schedule_work(struct sock *sk); 717 int mptcp_setsockopt(struct sock *sk, int level, int optname, 718 sockptr_t optval, unsigned int optlen); 719 int mptcp_getsockopt(struct sock *sk, int level, int optname, 720 char __user *optval, int __user *option); 721 722 u64 __mptcp_expand_seq(u64 old_seq, u64 cur_seq); 723 static inline u64 mptcp_expand_seq(u64 old_seq, u64 cur_seq, bool use_64bit) 724 { 725 if (use_64bit) 726 return cur_seq; 727 728 return __mptcp_expand_seq(old_seq, cur_seq); 729 } 730 void __mptcp_check_push(struct sock *sk, struct sock *ssk); 731 void __mptcp_data_acked(struct sock *sk); 732 void __mptcp_error_report(struct sock *sk); 733 bool mptcp_update_rcv_data_fin(struct mptcp_sock *msk, u64 data_fin_seq, bool use_64bit); 734 static inline bool mptcp_data_fin_enabled(const struct mptcp_sock *msk) 735 { 736 return READ_ONCE(msk->snd_data_fin_enable) && 737 READ_ONCE(msk->write_seq) == READ_ONCE(msk->snd_nxt); 738 } 739 740 static inline bool mptcp_propagate_sndbuf(struct sock *sk, struct sock *ssk) 741 { 742 if ((sk->sk_userlocks & SOCK_SNDBUF_LOCK) || ssk->sk_sndbuf <= READ_ONCE(sk->sk_sndbuf)) 743 return false; 744 745 WRITE_ONCE(sk->sk_sndbuf, ssk->sk_sndbuf); 746 return true; 747 } 748 749 static inline void mptcp_write_space(struct sock *sk) 750 { 751 if (sk_stream_is_writeable(sk)) { 752 /* pairs with memory barrier in mptcp_poll */ 753 smp_mb(); 754 if (test_and_clear_bit(MPTCP_NOSPACE, &mptcp_sk(sk)->flags)) 755 sk_stream_write_space(sk); 756 } 757 } 758 759 void mptcp_destroy_common(struct mptcp_sock *msk, unsigned int flags); 760 761 #define MPTCP_TOKEN_MAX_RETRIES 4 762 763 void __init mptcp_token_init(void); 764 static inline void mptcp_token_init_request(struct request_sock *req) 765 { 766 mptcp_subflow_rsk(req)->token_node.pprev = NULL; 767 } 768 769 int mptcp_token_new_request(struct request_sock *req); 770 void mptcp_token_destroy_request(struct request_sock *req); 771 int mptcp_token_new_connect(struct sock *ssk); 772 void mptcp_token_accept(struct mptcp_subflow_request_sock *r, 773 struct mptcp_sock *msk); 774 bool mptcp_token_exists(u32 token); 775 struct mptcp_sock *mptcp_token_get_sock(struct net *net, u32 token); 776 struct mptcp_sock *mptcp_token_iter_next(const struct net *net, long *s_slot, 777 long *s_num); 778 void mptcp_token_destroy(struct mptcp_sock *msk); 779 780 void mptcp_crypto_key_sha(u64 key, u32 *token, u64 *idsn); 781 782 void mptcp_crypto_hmac_sha(u64 key1, u64 key2, u8 *msg, int len, void *hmac); 783 __sum16 __mptcp_make_csum(u64 data_seq, u32 subflow_seq, u16 data_len, __wsum sum); 784 785 void __init mptcp_pm_init(void); 786 void mptcp_pm_data_init(struct mptcp_sock *msk); 787 void mptcp_pm_data_reset(struct mptcp_sock *msk); 788 int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info, 789 struct mptcp_addr_info *addr); 790 int mptcp_pm_parse_entry(struct nlattr *attr, struct genl_info *info, 791 bool require_family, 792 struct mptcp_pm_addr_entry *entry); 793 bool mptcp_pm_addr_families_match(const struct sock *sk, 794 const struct mptcp_addr_info *loc, 795 const struct mptcp_addr_info *rem); 796 void mptcp_pm_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); 797 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk); 798 void mptcp_pm_new_connection(struct mptcp_sock *msk, const struct sock *ssk, int server_side); 799 void mptcp_pm_fully_established(struct mptcp_sock *msk, const struct sock *ssk); 800 bool mptcp_pm_allow_new_subflow(struct mptcp_sock *msk); 801 void mptcp_pm_connection_closed(struct mptcp_sock *msk); 802 void mptcp_pm_subflow_established(struct mptcp_sock *msk); 803 bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk); 804 void mptcp_pm_subflow_check_next(struct mptcp_sock *msk, const struct sock *ssk, 805 const struct mptcp_subflow_context *subflow); 806 void mptcp_pm_add_addr_received(const struct sock *ssk, 807 const struct mptcp_addr_info *addr); 808 void mptcp_pm_add_addr_echoed(struct mptcp_sock *msk, 809 const struct mptcp_addr_info *addr); 810 void mptcp_pm_add_addr_send_ack(struct mptcp_sock *msk); 811 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk); 812 void mptcp_pm_rm_addr_received(struct mptcp_sock *msk, 813 const struct mptcp_rm_list *rm_list); 814 void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup); 815 void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq); 816 int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk, 817 struct mptcp_addr_info *addr, 818 struct mptcp_addr_info *rem, 819 u8 bkup); 820 bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk, 821 const struct mptcp_addr_info *addr); 822 void mptcp_pm_free_anno_list(struct mptcp_sock *msk); 823 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk); 824 struct mptcp_pm_add_entry * 825 mptcp_pm_del_add_timer(struct mptcp_sock *msk, 826 const struct mptcp_addr_info *addr, bool check_id); 827 struct mptcp_pm_add_entry * 828 mptcp_lookup_anno_list_by_saddr(const struct mptcp_sock *msk, 829 const struct mptcp_addr_info *addr); 830 int mptcp_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, 831 unsigned int id, 832 u8 *flags, int *ifindex); 833 int mptcp_pm_nl_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, unsigned int id, 834 u8 *flags, int *ifindex); 835 int mptcp_userspace_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, 836 unsigned int id, 837 u8 *flags, int *ifindex); 838 int mptcp_pm_set_flags(struct net *net, struct nlattr *token, 839 struct mptcp_pm_addr_entry *loc, 840 struct mptcp_pm_addr_entry *rem, u8 bkup); 841 int mptcp_pm_nl_set_flags(struct net *net, struct mptcp_pm_addr_entry *addr, u8 bkup); 842 int mptcp_userspace_pm_set_flags(struct net *net, struct nlattr *token, 843 struct mptcp_pm_addr_entry *loc, 844 struct mptcp_pm_addr_entry *rem, u8 bkup); 845 int mptcp_pm_announce_addr(struct mptcp_sock *msk, 846 const struct mptcp_addr_info *addr, 847 bool echo); 848 int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); 849 int mptcp_pm_remove_subflow(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list); 850 void mptcp_pm_remove_addrs(struct mptcp_sock *msk, struct list_head *rm_list); 851 void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk, 852 struct list_head *rm_list); 853 854 void mptcp_free_local_addr_list(struct mptcp_sock *msk); 855 int mptcp_nl_cmd_announce(struct sk_buff *skb, struct genl_info *info); 856 int mptcp_nl_cmd_remove(struct sk_buff *skb, struct genl_info *info); 857 int mptcp_nl_cmd_sf_create(struct sk_buff *skb, struct genl_info *info); 858 int mptcp_nl_cmd_sf_destroy(struct sk_buff *skb, struct genl_info *info); 859 860 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk, 861 const struct sock *ssk, gfp_t gfp); 862 void mptcp_event_addr_announced(const struct sock *ssk, const struct mptcp_addr_info *info); 863 void mptcp_event_addr_removed(const struct mptcp_sock *msk, u8 id); 864 void mptcp_event_pm_listener(const struct sock *ssk, 865 enum mptcp_event_type event); 866 bool mptcp_userspace_pm_active(const struct mptcp_sock *msk); 867 868 void mptcp_fastopen_gen_msk_ackseq(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow, 869 const struct mptcp_options_received *mp_opt); 870 void mptcp_fastopen_subflow_synack_set_params(struct mptcp_subflow_context *subflow, 871 struct request_sock *req); 872 873 static inline bool mptcp_pm_should_add_signal(struct mptcp_sock *msk) 874 { 875 return READ_ONCE(msk->pm.addr_signal) & 876 (BIT(MPTCP_ADD_ADDR_SIGNAL) | BIT(MPTCP_ADD_ADDR_ECHO)); 877 } 878 879 static inline bool mptcp_pm_should_add_signal_addr(struct mptcp_sock *msk) 880 { 881 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_SIGNAL); 882 } 883 884 static inline bool mptcp_pm_should_add_signal_echo(struct mptcp_sock *msk) 885 { 886 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_ADD_ADDR_ECHO); 887 } 888 889 static inline bool mptcp_pm_should_rm_signal(struct mptcp_sock *msk) 890 { 891 return READ_ONCE(msk->pm.addr_signal) & BIT(MPTCP_RM_ADDR_SIGNAL); 892 } 893 894 static inline bool mptcp_pm_is_userspace(const struct mptcp_sock *msk) 895 { 896 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_USERSPACE; 897 } 898 899 static inline bool mptcp_pm_is_kernel(const struct mptcp_sock *msk) 900 { 901 return READ_ONCE(msk->pm.pm_type) == MPTCP_PM_TYPE_KERNEL; 902 } 903 904 static inline unsigned int mptcp_add_addr_len(int family, bool echo, bool port) 905 { 906 u8 len = TCPOLEN_MPTCP_ADD_ADDR_BASE; 907 908 if (family == AF_INET6) 909 len = TCPOLEN_MPTCP_ADD_ADDR6_BASE; 910 if (!echo) 911 len += MPTCPOPT_THMAC_LEN; 912 /* account for 2 trailing 'nop' options */ 913 if (port) 914 len += TCPOLEN_MPTCP_PORT_LEN + TCPOLEN_MPTCP_PORT_ALIGN; 915 916 return len; 917 } 918 919 static inline int mptcp_rm_addr_len(const struct mptcp_rm_list *rm_list) 920 { 921 if (rm_list->nr == 0 || rm_list->nr > MPTCP_RM_IDS_MAX) 922 return -EINVAL; 923 924 return TCPOLEN_MPTCP_RM_ADDR_BASE + roundup(rm_list->nr - 1, 4) + 1; 925 } 926 927 bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, const struct sk_buff *skb, 928 unsigned int opt_size, unsigned int remaining, 929 struct mptcp_addr_info *addr, bool *echo, 930 bool *drop_other_suboptions); 931 bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining, 932 struct mptcp_rm_list *rm_list); 933 int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc); 934 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc); 935 int mptcp_userspace_pm_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc); 936 937 void __init mptcp_pm_nl_init(void); 938 void mptcp_pm_nl_work(struct mptcp_sock *msk); 939 void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk, 940 const struct mptcp_rm_list *rm_list); 941 unsigned int mptcp_pm_get_add_addr_signal_max(const struct mptcp_sock *msk); 942 unsigned int mptcp_pm_get_add_addr_accept_max(const struct mptcp_sock *msk); 943 unsigned int mptcp_pm_get_subflows_max(const struct mptcp_sock *msk); 944 unsigned int mptcp_pm_get_local_addr_max(const struct mptcp_sock *msk); 945 946 /* called under PM lock */ 947 static inline void __mptcp_pm_close_subflow(struct mptcp_sock *msk) 948 { 949 if (--msk->pm.subflows < mptcp_pm_get_subflows_max(msk)) 950 WRITE_ONCE(msk->pm.accept_subflow, true); 951 } 952 953 static inline void mptcp_pm_close_subflow(struct mptcp_sock *msk) 954 { 955 spin_lock_bh(&msk->pm.lock); 956 __mptcp_pm_close_subflow(msk); 957 spin_unlock_bh(&msk->pm.lock); 958 } 959 960 void mptcp_sockopt_sync(struct mptcp_sock *msk, struct sock *ssk); 961 void mptcp_sockopt_sync_locked(struct mptcp_sock *msk, struct sock *ssk); 962 963 static inline struct mptcp_ext *mptcp_get_ext(const struct sk_buff *skb) 964 { 965 return (struct mptcp_ext *)skb_ext_find(skb, SKB_EXT_MPTCP); 966 } 967 968 void mptcp_diag_subflow_init(struct tcp_ulp_ops *ops); 969 970 static inline bool __mptcp_check_fallback(const struct mptcp_sock *msk) 971 { 972 return test_bit(MPTCP_FALLBACK_DONE, &msk->flags); 973 } 974 975 static inline bool mptcp_check_fallback(const struct sock *sk) 976 { 977 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 978 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 979 980 return __mptcp_check_fallback(msk); 981 } 982 983 static inline void __mptcp_do_fallback(struct mptcp_sock *msk) 984 { 985 if (test_bit(MPTCP_FALLBACK_DONE, &msk->flags)) { 986 pr_debug("TCP fallback already done (msk=%p)", msk); 987 return; 988 } 989 set_bit(MPTCP_FALLBACK_DONE, &msk->flags); 990 } 991 992 static inline void mptcp_do_fallback(struct sock *ssk) 993 { 994 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 995 struct sock *sk = subflow->conn; 996 struct mptcp_sock *msk; 997 998 msk = mptcp_sk(sk); 999 __mptcp_do_fallback(msk); 1000 if (READ_ONCE(msk->snd_data_fin_enable) && !(ssk->sk_shutdown & SEND_SHUTDOWN)) { 1001 gfp_t saved_allocation = ssk->sk_allocation; 1002 1003 /* we are in a atomic (BH) scope, override ssk default for data 1004 * fin allocation 1005 */ 1006 ssk->sk_allocation = GFP_ATOMIC; 1007 ssk->sk_shutdown |= SEND_SHUTDOWN; 1008 tcp_shutdown(ssk, SEND_SHUTDOWN); 1009 ssk->sk_allocation = saved_allocation; 1010 } 1011 } 1012 1013 #define pr_fallback(a) pr_debug("%s:fallback to TCP (msk=%p)", __func__, a) 1014 1015 static inline bool mptcp_check_infinite_map(struct sk_buff *skb) 1016 { 1017 struct mptcp_ext *mpext; 1018 1019 mpext = skb ? mptcp_get_ext(skb) : NULL; 1020 if (mpext && mpext->infinite_map) 1021 return true; 1022 1023 return false; 1024 } 1025 1026 static inline bool is_active_ssk(struct mptcp_subflow_context *subflow) 1027 { 1028 return (subflow->request_mptcp || subflow->request_join); 1029 } 1030 1031 static inline bool subflow_simultaneous_connect(struct sock *sk) 1032 { 1033 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); 1034 1035 return sk->sk_state == TCP_ESTABLISHED && 1036 is_active_ssk(subflow) && 1037 !subflow->conn_finished; 1038 } 1039 1040 #ifdef CONFIG_SYN_COOKIES 1041 void subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 1042 struct sk_buff *skb); 1043 bool mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 1044 struct sk_buff *skb); 1045 void __init mptcp_join_cookie_init(void); 1046 #else 1047 static inline void 1048 subflow_init_req_cookie_join_save(const struct mptcp_subflow_request_sock *subflow_req, 1049 struct sk_buff *skb) {} 1050 static inline bool 1051 mptcp_token_join_cookie_init_state(struct mptcp_subflow_request_sock *subflow_req, 1052 struct sk_buff *skb) 1053 { 1054 return false; 1055 } 1056 1057 static inline void mptcp_join_cookie_init(void) {} 1058 #endif 1059 1060 #endif /* __MPTCP_PROTOCOL_H */ 1061