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