1 // SPDX-License-Identifier: GPL-2.0 2 /* Multipath TCP 3 * 4 * Copyright (c) 2021, Red Hat. 5 */ 6 7 #define pr_fmt(fmt) "MPTCP: " fmt 8 9 #include <linux/kernel.h> 10 #include <linux/module.h> 11 #include <net/sock.h> 12 #include <net/protocol.h> 13 #include <net/tcp.h> 14 #include <net/mptcp.h> 15 #include "protocol.h" 16 17 #define MIN_INFO_OPTLEN_SIZE 16 18 19 static struct sock *__mptcp_tcp_fallback(struct mptcp_sock *msk) 20 { 21 sock_owned_by_me((const struct sock *)msk); 22 23 if (likely(!__mptcp_check_fallback(msk))) 24 return NULL; 25 26 return msk->first; 27 } 28 29 static u32 sockopt_seq_reset(const struct sock *sk) 30 { 31 sock_owned_by_me(sk); 32 33 /* Highbits contain state. Allows to distinguish sockopt_seq 34 * of listener and established: 35 * s0 = new_listener() 36 * sockopt(s0) - seq is 1 37 * s1 = accept(s0) - s1 inherits seq 1 if listener sk (s0) 38 * sockopt(s0) - seq increments to 2 on s0 39 * sockopt(s1) // seq increments to 2 on s1 (different option) 40 * new ssk completes join, inherits options from s0 // seq 2 41 * Needs sync from mptcp join logic, but ssk->seq == msk->seq 42 * 43 * Set High order bits to sk_state so ssk->seq == msk->seq test 44 * will fail. 45 */ 46 47 return (u32)sk->sk_state << 24u; 48 } 49 50 static void sockopt_seq_inc(struct mptcp_sock *msk) 51 { 52 u32 seq = (msk->setsockopt_seq + 1) & 0x00ffffff; 53 54 msk->setsockopt_seq = sockopt_seq_reset((struct sock *)msk) + seq; 55 } 56 57 static int mptcp_get_int_option(struct mptcp_sock *msk, sockptr_t optval, 58 unsigned int optlen, int *val) 59 { 60 if (optlen < sizeof(int)) 61 return -EINVAL; 62 63 if (copy_from_sockptr(val, optval, sizeof(*val))) 64 return -EFAULT; 65 66 return 0; 67 } 68 69 static void mptcp_sol_socket_sync_intval(struct mptcp_sock *msk, int optname, int val) 70 { 71 struct mptcp_subflow_context *subflow; 72 struct sock *sk = (struct sock *)msk; 73 74 lock_sock(sk); 75 sockopt_seq_inc(msk); 76 77 mptcp_for_each_subflow(msk, subflow) { 78 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 79 bool slow = lock_sock_fast(ssk); 80 81 switch (optname) { 82 case SO_DEBUG: 83 sock_valbool_flag(ssk, SOCK_DBG, !!val); 84 break; 85 case SO_KEEPALIVE: 86 if (ssk->sk_prot->keepalive) 87 ssk->sk_prot->keepalive(ssk, !!val); 88 sock_valbool_flag(ssk, SOCK_KEEPOPEN, !!val); 89 break; 90 case SO_PRIORITY: 91 ssk->sk_priority = val; 92 break; 93 case SO_SNDBUF: 94 case SO_SNDBUFFORCE: 95 ssk->sk_userlocks |= SOCK_SNDBUF_LOCK; 96 WRITE_ONCE(ssk->sk_sndbuf, sk->sk_sndbuf); 97 break; 98 case SO_RCVBUF: 99 case SO_RCVBUFFORCE: 100 ssk->sk_userlocks |= SOCK_RCVBUF_LOCK; 101 WRITE_ONCE(ssk->sk_rcvbuf, sk->sk_rcvbuf); 102 break; 103 case SO_MARK: 104 if (READ_ONCE(ssk->sk_mark) != sk->sk_mark) { 105 ssk->sk_mark = sk->sk_mark; 106 sk_dst_reset(ssk); 107 } 108 break; 109 case SO_INCOMING_CPU: 110 WRITE_ONCE(ssk->sk_incoming_cpu, val); 111 break; 112 } 113 114 subflow->setsockopt_seq = msk->setsockopt_seq; 115 unlock_sock_fast(ssk, slow); 116 } 117 118 release_sock(sk); 119 } 120 121 static int mptcp_sol_socket_intval(struct mptcp_sock *msk, int optname, int val) 122 { 123 sockptr_t optval = KERNEL_SOCKPTR(&val); 124 struct sock *sk = (struct sock *)msk; 125 int ret; 126 127 ret = sock_setsockopt(sk->sk_socket, SOL_SOCKET, optname, 128 optval, sizeof(val)); 129 if (ret) 130 return ret; 131 132 mptcp_sol_socket_sync_intval(msk, optname, val); 133 return 0; 134 } 135 136 static void mptcp_so_incoming_cpu(struct mptcp_sock *msk, int val) 137 { 138 struct sock *sk = (struct sock *)msk; 139 140 WRITE_ONCE(sk->sk_incoming_cpu, val); 141 142 mptcp_sol_socket_sync_intval(msk, SO_INCOMING_CPU, val); 143 } 144 145 static int mptcp_setsockopt_sol_socket_tstamp(struct mptcp_sock *msk, int optname, int val) 146 { 147 sockptr_t optval = KERNEL_SOCKPTR(&val); 148 struct mptcp_subflow_context *subflow; 149 struct sock *sk = (struct sock *)msk; 150 int ret; 151 152 ret = sock_setsockopt(sk->sk_socket, SOL_SOCKET, optname, 153 optval, sizeof(val)); 154 if (ret) 155 return ret; 156 157 lock_sock(sk); 158 mptcp_for_each_subflow(msk, subflow) { 159 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 160 bool slow = lock_sock_fast(ssk); 161 162 sock_set_timestamp(sk, optname, !!val); 163 unlock_sock_fast(ssk, slow); 164 } 165 166 release_sock(sk); 167 return 0; 168 } 169 170 static int mptcp_setsockopt_sol_socket_int(struct mptcp_sock *msk, int optname, 171 sockptr_t optval, 172 unsigned int optlen) 173 { 174 int val, ret; 175 176 ret = mptcp_get_int_option(msk, optval, optlen, &val); 177 if (ret) 178 return ret; 179 180 switch (optname) { 181 case SO_KEEPALIVE: 182 mptcp_sol_socket_sync_intval(msk, optname, val); 183 return 0; 184 case SO_DEBUG: 185 case SO_MARK: 186 case SO_PRIORITY: 187 case SO_SNDBUF: 188 case SO_SNDBUFFORCE: 189 case SO_RCVBUF: 190 case SO_RCVBUFFORCE: 191 return mptcp_sol_socket_intval(msk, optname, val); 192 case SO_INCOMING_CPU: 193 mptcp_so_incoming_cpu(msk, val); 194 return 0; 195 case SO_TIMESTAMP_OLD: 196 case SO_TIMESTAMP_NEW: 197 case SO_TIMESTAMPNS_OLD: 198 case SO_TIMESTAMPNS_NEW: 199 return mptcp_setsockopt_sol_socket_tstamp(msk, optname, val); 200 } 201 202 return -ENOPROTOOPT; 203 } 204 205 static int mptcp_setsockopt_sol_socket_timestamping(struct mptcp_sock *msk, 206 int optname, 207 sockptr_t optval, 208 unsigned int optlen) 209 { 210 struct mptcp_subflow_context *subflow; 211 struct sock *sk = (struct sock *)msk; 212 struct so_timestamping timestamping; 213 int ret; 214 215 if (optlen == sizeof(timestamping)) { 216 if (copy_from_sockptr(×tamping, optval, 217 sizeof(timestamping))) 218 return -EFAULT; 219 } else if (optlen == sizeof(int)) { 220 memset(×tamping, 0, sizeof(timestamping)); 221 222 if (copy_from_sockptr(×tamping.flags, optval, sizeof(int))) 223 return -EFAULT; 224 } else { 225 return -EINVAL; 226 } 227 228 ret = sock_setsockopt(sk->sk_socket, SOL_SOCKET, optname, 229 KERNEL_SOCKPTR(×tamping), 230 sizeof(timestamping)); 231 if (ret) 232 return ret; 233 234 lock_sock(sk); 235 236 mptcp_for_each_subflow(msk, subflow) { 237 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 238 bool slow = lock_sock_fast(ssk); 239 240 sock_set_timestamping(sk, optname, timestamping); 241 unlock_sock_fast(ssk, slow); 242 } 243 244 release_sock(sk); 245 246 return 0; 247 } 248 249 static int mptcp_setsockopt_sol_socket_linger(struct mptcp_sock *msk, sockptr_t optval, 250 unsigned int optlen) 251 { 252 struct mptcp_subflow_context *subflow; 253 struct sock *sk = (struct sock *)msk; 254 struct linger ling; 255 sockptr_t kopt; 256 int ret; 257 258 if (optlen < sizeof(ling)) 259 return -EINVAL; 260 261 if (copy_from_sockptr(&ling, optval, sizeof(ling))) 262 return -EFAULT; 263 264 kopt = KERNEL_SOCKPTR(&ling); 265 ret = sock_setsockopt(sk->sk_socket, SOL_SOCKET, SO_LINGER, kopt, sizeof(ling)); 266 if (ret) 267 return ret; 268 269 lock_sock(sk); 270 sockopt_seq_inc(msk); 271 mptcp_for_each_subflow(msk, subflow) { 272 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 273 bool slow = lock_sock_fast(ssk); 274 275 if (!ling.l_onoff) { 276 sock_reset_flag(ssk, SOCK_LINGER); 277 } else { 278 ssk->sk_lingertime = sk->sk_lingertime; 279 sock_set_flag(ssk, SOCK_LINGER); 280 } 281 282 subflow->setsockopt_seq = msk->setsockopt_seq; 283 unlock_sock_fast(ssk, slow); 284 } 285 286 release_sock(sk); 287 return 0; 288 } 289 290 static int mptcp_setsockopt_sol_socket(struct mptcp_sock *msk, int optname, 291 sockptr_t optval, unsigned int optlen) 292 { 293 struct sock *sk = (struct sock *)msk; 294 struct socket *ssock; 295 int ret; 296 297 switch (optname) { 298 case SO_REUSEPORT: 299 case SO_REUSEADDR: 300 case SO_BINDTODEVICE: 301 case SO_BINDTOIFINDEX: 302 lock_sock(sk); 303 ssock = __mptcp_nmpc_socket(msk); 304 if (!ssock) { 305 release_sock(sk); 306 return -EINVAL; 307 } 308 309 ret = sock_setsockopt(ssock, SOL_SOCKET, optname, optval, optlen); 310 if (ret == 0) { 311 if (optname == SO_REUSEPORT) 312 sk->sk_reuseport = ssock->sk->sk_reuseport; 313 else if (optname == SO_REUSEADDR) 314 sk->sk_reuse = ssock->sk->sk_reuse; 315 else if (optname == SO_BINDTODEVICE) 316 sk->sk_bound_dev_if = ssock->sk->sk_bound_dev_if; 317 else if (optname == SO_BINDTOIFINDEX) 318 sk->sk_bound_dev_if = ssock->sk->sk_bound_dev_if; 319 } 320 release_sock(sk); 321 return ret; 322 case SO_KEEPALIVE: 323 case SO_PRIORITY: 324 case SO_SNDBUF: 325 case SO_SNDBUFFORCE: 326 case SO_RCVBUF: 327 case SO_RCVBUFFORCE: 328 case SO_MARK: 329 case SO_INCOMING_CPU: 330 case SO_DEBUG: 331 case SO_TIMESTAMP_OLD: 332 case SO_TIMESTAMP_NEW: 333 case SO_TIMESTAMPNS_OLD: 334 case SO_TIMESTAMPNS_NEW: 335 return mptcp_setsockopt_sol_socket_int(msk, optname, optval, 336 optlen); 337 case SO_TIMESTAMPING_OLD: 338 case SO_TIMESTAMPING_NEW: 339 return mptcp_setsockopt_sol_socket_timestamping(msk, optname, 340 optval, optlen); 341 case SO_LINGER: 342 return mptcp_setsockopt_sol_socket_linger(msk, optval, optlen); 343 case SO_RCVLOWAT: 344 case SO_RCVTIMEO_OLD: 345 case SO_RCVTIMEO_NEW: 346 case SO_SNDTIMEO_OLD: 347 case SO_SNDTIMEO_NEW: 348 case SO_BUSY_POLL: 349 case SO_PREFER_BUSY_POLL: 350 case SO_BUSY_POLL_BUDGET: 351 /* No need to copy: only relevant for msk */ 352 return sock_setsockopt(sk->sk_socket, SOL_SOCKET, optname, optval, optlen); 353 case SO_NO_CHECK: 354 case SO_DONTROUTE: 355 case SO_BROADCAST: 356 case SO_BSDCOMPAT: 357 case SO_PASSCRED: 358 case SO_PASSSEC: 359 case SO_RXQ_OVFL: 360 case SO_WIFI_STATUS: 361 case SO_NOFCS: 362 case SO_SELECT_ERR_QUEUE: 363 return 0; 364 } 365 366 /* SO_OOBINLINE is not supported, let's avoid the related mess 367 * SO_ATTACH_FILTER, SO_ATTACH_BPF, SO_ATTACH_REUSEPORT_CBPF, 368 * SO_DETACH_REUSEPORT_BPF, SO_DETACH_FILTER, SO_LOCK_FILTER, 369 * we must be careful with subflows 370 * 371 * SO_ATTACH_REUSEPORT_EBPF is not supported, at it checks 372 * explicitly the sk_protocol field 373 * 374 * SO_PEEK_OFF is unsupported, as it is for plain TCP 375 * SO_MAX_PACING_RATE is unsupported, we must be careful with subflows 376 * SO_CNX_ADVICE is currently unsupported, could possibly be relevant, 377 * but likely needs careful design 378 * 379 * SO_ZEROCOPY is currently unsupported, TODO in sndmsg 380 * SO_TXTIME is currently unsupported 381 */ 382 383 return -EOPNOTSUPP; 384 } 385 386 static int mptcp_setsockopt_v6(struct mptcp_sock *msk, int optname, 387 sockptr_t optval, unsigned int optlen) 388 { 389 struct sock *sk = (struct sock *)msk; 390 int ret = -EOPNOTSUPP; 391 struct socket *ssock; 392 393 switch (optname) { 394 case IPV6_V6ONLY: 395 case IPV6_TRANSPARENT: 396 case IPV6_FREEBIND: 397 lock_sock(sk); 398 ssock = __mptcp_nmpc_socket(msk); 399 if (!ssock) { 400 release_sock(sk); 401 return -EINVAL; 402 } 403 404 ret = tcp_setsockopt(ssock->sk, SOL_IPV6, optname, optval, optlen); 405 if (ret != 0) { 406 release_sock(sk); 407 return ret; 408 } 409 410 sockopt_seq_inc(msk); 411 412 switch (optname) { 413 case IPV6_V6ONLY: 414 sk->sk_ipv6only = ssock->sk->sk_ipv6only; 415 break; 416 case IPV6_TRANSPARENT: 417 inet_sk(sk)->transparent = inet_sk(ssock->sk)->transparent; 418 break; 419 case IPV6_FREEBIND: 420 inet_sk(sk)->freebind = inet_sk(ssock->sk)->freebind; 421 break; 422 } 423 424 release_sock(sk); 425 break; 426 } 427 428 return ret; 429 } 430 431 static bool mptcp_supported_sockopt(int level, int optname) 432 { 433 if (level == SOL_IP) { 434 switch (optname) { 435 /* should work fine */ 436 case IP_FREEBIND: 437 case IP_TRANSPARENT: 438 439 /* the following are control cmsg related */ 440 case IP_PKTINFO: 441 case IP_RECVTTL: 442 case IP_RECVTOS: 443 case IP_RECVOPTS: 444 case IP_RETOPTS: 445 case IP_PASSSEC: 446 case IP_RECVORIGDSTADDR: 447 case IP_CHECKSUM: 448 case IP_RECVFRAGSIZE: 449 450 /* common stuff that need some love */ 451 case IP_TOS: 452 case IP_TTL: 453 case IP_BIND_ADDRESS_NO_PORT: 454 case IP_MTU_DISCOVER: 455 case IP_RECVERR: 456 457 /* possibly less common may deserve some love */ 458 case IP_MINTTL: 459 460 /* the following is apparently a no-op for plain TCP */ 461 case IP_RECVERR_RFC4884: 462 return true; 463 } 464 465 /* IP_OPTIONS is not supported, needs subflow care */ 466 /* IP_HDRINCL, IP_NODEFRAG are not supported, RAW specific */ 467 /* IP_MULTICAST_TTL, IP_MULTICAST_LOOP, IP_UNICAST_IF, 468 * IP_ADD_MEMBERSHIP, IP_ADD_SOURCE_MEMBERSHIP, IP_DROP_MEMBERSHIP, 469 * IP_DROP_SOURCE_MEMBERSHIP, IP_BLOCK_SOURCE, IP_UNBLOCK_SOURCE, 470 * MCAST_JOIN_GROUP, MCAST_LEAVE_GROUP MCAST_JOIN_SOURCE_GROUP, 471 * MCAST_LEAVE_SOURCE_GROUP, MCAST_BLOCK_SOURCE, MCAST_UNBLOCK_SOURCE, 472 * MCAST_MSFILTER, IP_MULTICAST_ALL are not supported, better not deal 473 * with mcast stuff 474 */ 475 /* IP_IPSEC_POLICY, IP_XFRM_POLICY are nut supported, unrelated here */ 476 return false; 477 } 478 if (level == SOL_IPV6) { 479 switch (optname) { 480 case IPV6_V6ONLY: 481 482 /* the following are control cmsg related */ 483 case IPV6_RECVPKTINFO: 484 case IPV6_2292PKTINFO: 485 case IPV6_RECVHOPLIMIT: 486 case IPV6_2292HOPLIMIT: 487 case IPV6_RECVRTHDR: 488 case IPV6_2292RTHDR: 489 case IPV6_RECVHOPOPTS: 490 case IPV6_2292HOPOPTS: 491 case IPV6_RECVDSTOPTS: 492 case IPV6_2292DSTOPTS: 493 case IPV6_RECVTCLASS: 494 case IPV6_FLOWINFO: 495 case IPV6_RECVPATHMTU: 496 case IPV6_RECVORIGDSTADDR: 497 case IPV6_RECVFRAGSIZE: 498 499 /* the following ones need some love but are quite common */ 500 case IPV6_TCLASS: 501 case IPV6_TRANSPARENT: 502 case IPV6_FREEBIND: 503 case IPV6_PKTINFO: 504 case IPV6_2292PKTOPTIONS: 505 case IPV6_UNICAST_HOPS: 506 case IPV6_MTU_DISCOVER: 507 case IPV6_MTU: 508 case IPV6_RECVERR: 509 case IPV6_FLOWINFO_SEND: 510 case IPV6_FLOWLABEL_MGR: 511 case IPV6_MINHOPCOUNT: 512 case IPV6_DONTFRAG: 513 case IPV6_AUTOFLOWLABEL: 514 515 /* the following one is a no-op for plain TCP */ 516 case IPV6_RECVERR_RFC4884: 517 return true; 518 } 519 520 /* IPV6_HOPOPTS, IPV6_RTHDRDSTOPTS, IPV6_RTHDR, IPV6_DSTOPTS are 521 * not supported 522 */ 523 /* IPV6_MULTICAST_HOPS, IPV6_MULTICAST_LOOP, IPV6_UNICAST_IF, 524 * IPV6_MULTICAST_IF, IPV6_ADDRFORM, 525 * IPV6_ADD_MEMBERSHIP, IPV6_DROP_MEMBERSHIP, IPV6_JOIN_ANYCAST, 526 * IPV6_LEAVE_ANYCAST, IPV6_MULTICAST_ALL, MCAST_JOIN_GROUP, MCAST_LEAVE_GROUP, 527 * MCAST_JOIN_SOURCE_GROUP, MCAST_LEAVE_SOURCE_GROUP, 528 * MCAST_BLOCK_SOURCE, MCAST_UNBLOCK_SOURCE, MCAST_MSFILTER 529 * are not supported better not deal with mcast 530 */ 531 /* IPV6_ROUTER_ALERT, IPV6_ROUTER_ALERT_ISOLATE are not supported, since are evil */ 532 533 /* IPV6_IPSEC_POLICY, IPV6_XFRM_POLICY are not supported */ 534 /* IPV6_ADDR_PREFERENCES is not supported, we must be careful with subflows */ 535 return false; 536 } 537 if (level == SOL_TCP) { 538 switch (optname) { 539 /* the following are no-op or should work just fine */ 540 case TCP_THIN_DUPACK: 541 case TCP_DEFER_ACCEPT: 542 543 /* the following need some love */ 544 case TCP_MAXSEG: 545 case TCP_NODELAY: 546 case TCP_THIN_LINEAR_TIMEOUTS: 547 case TCP_CONGESTION: 548 case TCP_CORK: 549 case TCP_KEEPIDLE: 550 case TCP_KEEPINTVL: 551 case TCP_KEEPCNT: 552 case TCP_SYNCNT: 553 case TCP_SAVE_SYN: 554 case TCP_LINGER2: 555 case TCP_WINDOW_CLAMP: 556 case TCP_QUICKACK: 557 case TCP_USER_TIMEOUT: 558 case TCP_TIMESTAMP: 559 case TCP_NOTSENT_LOWAT: 560 case TCP_TX_DELAY: 561 case TCP_INQ: 562 return true; 563 } 564 565 /* TCP_MD5SIG, TCP_MD5SIG_EXT are not supported, MD5 is not compatible with MPTCP */ 566 567 /* TCP_REPAIR, TCP_REPAIR_QUEUE, TCP_QUEUE_SEQ, TCP_REPAIR_OPTIONS, 568 * TCP_REPAIR_WINDOW are not supported, better avoid this mess 569 */ 570 /* TCP_FASTOPEN_KEY, TCP_FASTOPEN TCP_FASTOPEN_CONNECT, TCP_FASTOPEN_NO_COOKIE, 571 * are not supported fastopen is currently unsupported 572 */ 573 } 574 return false; 575 } 576 577 static int mptcp_setsockopt_sol_tcp_congestion(struct mptcp_sock *msk, sockptr_t optval, 578 unsigned int optlen) 579 { 580 struct mptcp_subflow_context *subflow; 581 struct sock *sk = (struct sock *)msk; 582 char name[TCP_CA_NAME_MAX]; 583 bool cap_net_admin; 584 int ret; 585 586 if (optlen < 1) 587 return -EINVAL; 588 589 ret = strncpy_from_sockptr(name, optval, 590 min_t(long, TCP_CA_NAME_MAX - 1, optlen)); 591 if (ret < 0) 592 return -EFAULT; 593 594 name[ret] = 0; 595 596 cap_net_admin = ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN); 597 598 ret = 0; 599 lock_sock(sk); 600 sockopt_seq_inc(msk); 601 mptcp_for_each_subflow(msk, subflow) { 602 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 603 int err; 604 605 lock_sock(ssk); 606 err = tcp_set_congestion_control(ssk, name, true, cap_net_admin); 607 if (err < 0 && ret == 0) 608 ret = err; 609 subflow->setsockopt_seq = msk->setsockopt_seq; 610 release_sock(ssk); 611 } 612 613 if (ret == 0) 614 strcpy(msk->ca_name, name); 615 616 release_sock(sk); 617 return ret; 618 } 619 620 static int mptcp_setsockopt_sol_tcp_cork(struct mptcp_sock *msk, sockptr_t optval, 621 unsigned int optlen) 622 { 623 struct mptcp_subflow_context *subflow; 624 struct sock *sk = (struct sock *)msk; 625 int val; 626 627 if (optlen < sizeof(int)) 628 return -EINVAL; 629 630 if (copy_from_sockptr(&val, optval, sizeof(val))) 631 return -EFAULT; 632 633 lock_sock(sk); 634 sockopt_seq_inc(msk); 635 msk->cork = !!val; 636 mptcp_for_each_subflow(msk, subflow) { 637 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 638 639 lock_sock(ssk); 640 __tcp_sock_set_cork(ssk, !!val); 641 release_sock(ssk); 642 } 643 if (!val) 644 mptcp_check_and_set_pending(sk); 645 release_sock(sk); 646 647 return 0; 648 } 649 650 static int mptcp_setsockopt_sol_tcp_nodelay(struct mptcp_sock *msk, sockptr_t optval, 651 unsigned int optlen) 652 { 653 struct mptcp_subflow_context *subflow; 654 struct sock *sk = (struct sock *)msk; 655 int val; 656 657 if (optlen < sizeof(int)) 658 return -EINVAL; 659 660 if (copy_from_sockptr(&val, optval, sizeof(val))) 661 return -EFAULT; 662 663 lock_sock(sk); 664 sockopt_seq_inc(msk); 665 msk->nodelay = !!val; 666 mptcp_for_each_subflow(msk, subflow) { 667 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 668 669 lock_sock(ssk); 670 __tcp_sock_set_nodelay(ssk, !!val); 671 release_sock(ssk); 672 } 673 if (val) 674 mptcp_check_and_set_pending(sk); 675 release_sock(sk); 676 677 return 0; 678 } 679 680 static int mptcp_setsockopt_sol_ip_set_transparent(struct mptcp_sock *msk, int optname, 681 sockptr_t optval, unsigned int optlen) 682 { 683 struct sock *sk = (struct sock *)msk; 684 struct inet_sock *issk; 685 struct socket *ssock; 686 int err; 687 688 err = ip_setsockopt(sk, SOL_IP, optname, optval, optlen); 689 if (err != 0) 690 return err; 691 692 lock_sock(sk); 693 694 ssock = __mptcp_nmpc_socket(msk); 695 if (!ssock) { 696 release_sock(sk); 697 return -EINVAL; 698 } 699 700 issk = inet_sk(ssock->sk); 701 702 switch (optname) { 703 case IP_FREEBIND: 704 issk->freebind = inet_sk(sk)->freebind; 705 break; 706 case IP_TRANSPARENT: 707 issk->transparent = inet_sk(sk)->transparent; 708 break; 709 default: 710 release_sock(sk); 711 WARN_ON_ONCE(1); 712 return -EOPNOTSUPP; 713 } 714 715 sockopt_seq_inc(msk); 716 release_sock(sk); 717 return 0; 718 } 719 720 static int mptcp_setsockopt_v4_set_tos(struct mptcp_sock *msk, int optname, 721 sockptr_t optval, unsigned int optlen) 722 { 723 struct mptcp_subflow_context *subflow; 724 struct sock *sk = (struct sock *)msk; 725 int err, val; 726 727 err = ip_setsockopt(sk, SOL_IP, optname, optval, optlen); 728 729 if (err != 0) 730 return err; 731 732 lock_sock(sk); 733 sockopt_seq_inc(msk); 734 val = inet_sk(sk)->tos; 735 mptcp_for_each_subflow(msk, subflow) { 736 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 737 738 __ip_sock_set_tos(ssk, val); 739 } 740 release_sock(sk); 741 742 return err; 743 } 744 745 static int mptcp_setsockopt_v4(struct mptcp_sock *msk, int optname, 746 sockptr_t optval, unsigned int optlen) 747 { 748 switch (optname) { 749 case IP_FREEBIND: 750 case IP_TRANSPARENT: 751 return mptcp_setsockopt_sol_ip_set_transparent(msk, optname, optval, optlen); 752 case IP_TOS: 753 return mptcp_setsockopt_v4_set_tos(msk, optname, optval, optlen); 754 } 755 756 return -EOPNOTSUPP; 757 } 758 759 static int mptcp_setsockopt_sol_tcp(struct mptcp_sock *msk, int optname, 760 sockptr_t optval, unsigned int optlen) 761 { 762 struct sock *sk = (void *)msk; 763 int ret, val; 764 765 switch (optname) { 766 case TCP_INQ: 767 ret = mptcp_get_int_option(msk, optval, optlen, &val); 768 if (ret) 769 return ret; 770 if (val < 0 || val > 1) 771 return -EINVAL; 772 773 lock_sock(sk); 774 msk->recvmsg_inq = !!val; 775 release_sock(sk); 776 return 0; 777 case TCP_ULP: 778 return -EOPNOTSUPP; 779 case TCP_CONGESTION: 780 return mptcp_setsockopt_sol_tcp_congestion(msk, optval, optlen); 781 case TCP_CORK: 782 return mptcp_setsockopt_sol_tcp_cork(msk, optval, optlen); 783 case TCP_NODELAY: 784 return mptcp_setsockopt_sol_tcp_nodelay(msk, optval, optlen); 785 } 786 787 return -EOPNOTSUPP; 788 } 789 790 int mptcp_setsockopt(struct sock *sk, int level, int optname, 791 sockptr_t optval, unsigned int optlen) 792 { 793 struct mptcp_sock *msk = mptcp_sk(sk); 794 struct sock *ssk; 795 796 pr_debug("msk=%p", msk); 797 798 if (level == SOL_SOCKET) 799 return mptcp_setsockopt_sol_socket(msk, optname, optval, optlen); 800 801 if (!mptcp_supported_sockopt(level, optname)) 802 return -ENOPROTOOPT; 803 804 /* @@ the meaning of setsockopt() when the socket is connected and 805 * there are multiple subflows is not yet defined. It is up to the 806 * MPTCP-level socket to configure the subflows until the subflow 807 * is in TCP fallback, when TCP socket options are passed through 808 * to the one remaining subflow. 809 */ 810 lock_sock(sk); 811 ssk = __mptcp_tcp_fallback(msk); 812 release_sock(sk); 813 if (ssk) 814 return tcp_setsockopt(ssk, level, optname, optval, optlen); 815 816 if (level == SOL_IP) 817 return mptcp_setsockopt_v4(msk, optname, optval, optlen); 818 819 if (level == SOL_IPV6) 820 return mptcp_setsockopt_v6(msk, optname, optval, optlen); 821 822 if (level == SOL_TCP) 823 return mptcp_setsockopt_sol_tcp(msk, optname, optval, optlen); 824 825 return -EOPNOTSUPP; 826 } 827 828 static int mptcp_getsockopt_first_sf_only(struct mptcp_sock *msk, int level, int optname, 829 char __user *optval, int __user *optlen) 830 { 831 struct sock *sk = (struct sock *)msk; 832 struct socket *ssock; 833 int ret = -EINVAL; 834 struct sock *ssk; 835 836 lock_sock(sk); 837 ssk = msk->first; 838 if (ssk) { 839 ret = tcp_getsockopt(ssk, level, optname, optval, optlen); 840 goto out; 841 } 842 843 ssock = __mptcp_nmpc_socket(msk); 844 if (!ssock) 845 goto out; 846 847 ret = tcp_getsockopt(ssock->sk, level, optname, optval, optlen); 848 849 out: 850 release_sock(sk); 851 return ret; 852 } 853 854 void mptcp_diag_fill_info(struct mptcp_sock *msk, struct mptcp_info *info) 855 { 856 struct sock *sk = &msk->sk.icsk_inet.sk; 857 u32 flags = 0; 858 bool slow; 859 u8 val; 860 861 memset(info, 0, sizeof(*info)); 862 863 slow = lock_sock_fast(sk); 864 865 info->mptcpi_subflows = READ_ONCE(msk->pm.subflows); 866 info->mptcpi_add_addr_signal = READ_ONCE(msk->pm.add_addr_signaled); 867 info->mptcpi_add_addr_accepted = READ_ONCE(msk->pm.add_addr_accepted); 868 info->mptcpi_local_addr_used = READ_ONCE(msk->pm.local_addr_used); 869 info->mptcpi_subflows_max = mptcp_pm_get_subflows_max(msk); 870 val = mptcp_pm_get_add_addr_signal_max(msk); 871 info->mptcpi_add_addr_signal_max = val; 872 val = mptcp_pm_get_add_addr_accept_max(msk); 873 info->mptcpi_add_addr_accepted_max = val; 874 info->mptcpi_local_addr_max = mptcp_pm_get_local_addr_max(msk); 875 if (test_bit(MPTCP_FALLBACK_DONE, &msk->flags)) 876 flags |= MPTCP_INFO_FLAG_FALLBACK; 877 if (READ_ONCE(msk->can_ack)) 878 flags |= MPTCP_INFO_FLAG_REMOTE_KEY_RECEIVED; 879 info->mptcpi_flags = flags; 880 info->mptcpi_token = READ_ONCE(msk->token); 881 info->mptcpi_write_seq = READ_ONCE(msk->write_seq); 882 info->mptcpi_snd_una = READ_ONCE(msk->snd_una); 883 info->mptcpi_rcv_nxt = READ_ONCE(msk->ack_seq); 884 info->mptcpi_csum_enabled = READ_ONCE(msk->csum_enabled); 885 886 unlock_sock_fast(sk, slow); 887 } 888 EXPORT_SYMBOL_GPL(mptcp_diag_fill_info); 889 890 static int mptcp_getsockopt_info(struct mptcp_sock *msk, char __user *optval, int __user *optlen) 891 { 892 struct mptcp_info m_info; 893 int len; 894 895 if (get_user(len, optlen)) 896 return -EFAULT; 897 898 len = min_t(unsigned int, len, sizeof(struct mptcp_info)); 899 900 mptcp_diag_fill_info(msk, &m_info); 901 902 if (put_user(len, optlen)) 903 return -EFAULT; 904 905 if (copy_to_user(optval, &m_info, len)) 906 return -EFAULT; 907 908 return 0; 909 } 910 911 static int mptcp_put_subflow_data(struct mptcp_subflow_data *sfd, 912 char __user *optval, 913 u32 copied, 914 int __user *optlen) 915 { 916 u32 copylen = min_t(u32, sfd->size_subflow_data, sizeof(*sfd)); 917 918 if (copied) 919 copied += sfd->size_subflow_data; 920 else 921 copied = copylen; 922 923 if (put_user(copied, optlen)) 924 return -EFAULT; 925 926 if (copy_to_user(optval, sfd, copylen)) 927 return -EFAULT; 928 929 return 0; 930 } 931 932 static int mptcp_get_subflow_data(struct mptcp_subflow_data *sfd, 933 char __user *optval, int __user *optlen) 934 { 935 int len, copylen; 936 937 if (get_user(len, optlen)) 938 return -EFAULT; 939 940 /* if mptcp_subflow_data size is changed, need to adjust 941 * this function to deal with programs using old version. 942 */ 943 BUILD_BUG_ON(sizeof(*sfd) != MIN_INFO_OPTLEN_SIZE); 944 945 if (len < MIN_INFO_OPTLEN_SIZE) 946 return -EINVAL; 947 948 memset(sfd, 0, sizeof(*sfd)); 949 950 copylen = min_t(unsigned int, len, sizeof(*sfd)); 951 if (copy_from_user(sfd, optval, copylen)) 952 return -EFAULT; 953 954 /* size_subflow_data is u32, but len is signed */ 955 if (sfd->size_subflow_data > INT_MAX || 956 sfd->size_user > INT_MAX) 957 return -EINVAL; 958 959 if (sfd->size_subflow_data < MIN_INFO_OPTLEN_SIZE || 960 sfd->size_subflow_data > len) 961 return -EINVAL; 962 963 if (sfd->num_subflows || sfd->size_kernel) 964 return -EINVAL; 965 966 return len - sfd->size_subflow_data; 967 } 968 969 static int mptcp_getsockopt_tcpinfo(struct mptcp_sock *msk, char __user *optval, 970 int __user *optlen) 971 { 972 struct mptcp_subflow_context *subflow; 973 struct sock *sk = &msk->sk.icsk_inet.sk; 974 unsigned int sfcount = 0, copied = 0; 975 struct mptcp_subflow_data sfd; 976 char __user *infoptr; 977 int len; 978 979 len = mptcp_get_subflow_data(&sfd, optval, optlen); 980 if (len < 0) 981 return len; 982 983 sfd.size_kernel = sizeof(struct tcp_info); 984 sfd.size_user = min_t(unsigned int, sfd.size_user, 985 sizeof(struct tcp_info)); 986 987 infoptr = optval + sfd.size_subflow_data; 988 989 lock_sock(sk); 990 991 mptcp_for_each_subflow(msk, subflow) { 992 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 993 994 ++sfcount; 995 996 if (len && len >= sfd.size_user) { 997 struct tcp_info info; 998 999 tcp_get_info(ssk, &info); 1000 1001 if (copy_to_user(infoptr, &info, sfd.size_user)) { 1002 release_sock(sk); 1003 return -EFAULT; 1004 } 1005 1006 infoptr += sfd.size_user; 1007 copied += sfd.size_user; 1008 len -= sfd.size_user; 1009 } 1010 } 1011 1012 release_sock(sk); 1013 1014 sfd.num_subflows = sfcount; 1015 1016 if (mptcp_put_subflow_data(&sfd, optval, copied, optlen)) 1017 return -EFAULT; 1018 1019 return 0; 1020 } 1021 1022 static void mptcp_get_sub_addrs(const struct sock *sk, struct mptcp_subflow_addrs *a) 1023 { 1024 struct inet_sock *inet = inet_sk(sk); 1025 1026 memset(a, 0, sizeof(*a)); 1027 1028 if (sk->sk_family == AF_INET) { 1029 a->sin_local.sin_family = AF_INET; 1030 a->sin_local.sin_port = inet->inet_sport; 1031 a->sin_local.sin_addr.s_addr = inet->inet_rcv_saddr; 1032 1033 if (!a->sin_local.sin_addr.s_addr) 1034 a->sin_local.sin_addr.s_addr = inet->inet_saddr; 1035 1036 a->sin_remote.sin_family = AF_INET; 1037 a->sin_remote.sin_port = inet->inet_dport; 1038 a->sin_remote.sin_addr.s_addr = inet->inet_daddr; 1039 #if IS_ENABLED(CONFIG_IPV6) 1040 } else if (sk->sk_family == AF_INET6) { 1041 const struct ipv6_pinfo *np = inet6_sk(sk); 1042 1043 if (WARN_ON_ONCE(!np)) 1044 return; 1045 1046 a->sin6_local.sin6_family = AF_INET6; 1047 a->sin6_local.sin6_port = inet->inet_sport; 1048 1049 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr)) 1050 a->sin6_local.sin6_addr = np->saddr; 1051 else 1052 a->sin6_local.sin6_addr = sk->sk_v6_rcv_saddr; 1053 1054 a->sin6_remote.sin6_family = AF_INET6; 1055 a->sin6_remote.sin6_port = inet->inet_dport; 1056 a->sin6_remote.sin6_addr = sk->sk_v6_daddr; 1057 #endif 1058 } 1059 } 1060 1061 static int mptcp_getsockopt_subflow_addrs(struct mptcp_sock *msk, char __user *optval, 1062 int __user *optlen) 1063 { 1064 struct sock *sk = &msk->sk.icsk_inet.sk; 1065 struct mptcp_subflow_context *subflow; 1066 unsigned int sfcount = 0, copied = 0; 1067 struct mptcp_subflow_data sfd; 1068 char __user *addrptr; 1069 int len; 1070 1071 len = mptcp_get_subflow_data(&sfd, optval, optlen); 1072 if (len < 0) 1073 return len; 1074 1075 sfd.size_kernel = sizeof(struct mptcp_subflow_addrs); 1076 sfd.size_user = min_t(unsigned int, sfd.size_user, 1077 sizeof(struct mptcp_subflow_addrs)); 1078 1079 addrptr = optval + sfd.size_subflow_data; 1080 1081 lock_sock(sk); 1082 1083 mptcp_for_each_subflow(msk, subflow) { 1084 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 1085 1086 ++sfcount; 1087 1088 if (len && len >= sfd.size_user) { 1089 struct mptcp_subflow_addrs a; 1090 1091 mptcp_get_sub_addrs(ssk, &a); 1092 1093 if (copy_to_user(addrptr, &a, sfd.size_user)) { 1094 release_sock(sk); 1095 return -EFAULT; 1096 } 1097 1098 addrptr += sfd.size_user; 1099 copied += sfd.size_user; 1100 len -= sfd.size_user; 1101 } 1102 } 1103 1104 release_sock(sk); 1105 1106 sfd.num_subflows = sfcount; 1107 1108 if (mptcp_put_subflow_data(&sfd, optval, copied, optlen)) 1109 return -EFAULT; 1110 1111 return 0; 1112 } 1113 1114 static int mptcp_put_int_option(struct mptcp_sock *msk, char __user *optval, 1115 int __user *optlen, int val) 1116 { 1117 int len; 1118 1119 if (get_user(len, optlen)) 1120 return -EFAULT; 1121 if (len < 0) 1122 return -EINVAL; 1123 1124 if (len < sizeof(int) && len > 0 && val >= 0 && val <= 255) { 1125 unsigned char ucval = (unsigned char)val; 1126 1127 len = 1; 1128 if (put_user(len, optlen)) 1129 return -EFAULT; 1130 if (copy_to_user(optval, &ucval, 1)) 1131 return -EFAULT; 1132 } else { 1133 len = min_t(unsigned int, len, sizeof(int)); 1134 if (put_user(len, optlen)) 1135 return -EFAULT; 1136 if (copy_to_user(optval, &val, len)) 1137 return -EFAULT; 1138 } 1139 1140 return 0; 1141 } 1142 1143 static int mptcp_getsockopt_sol_tcp(struct mptcp_sock *msk, int optname, 1144 char __user *optval, int __user *optlen) 1145 { 1146 switch (optname) { 1147 case TCP_ULP: 1148 case TCP_CONGESTION: 1149 case TCP_INFO: 1150 case TCP_CC_INFO: 1151 return mptcp_getsockopt_first_sf_only(msk, SOL_TCP, optname, 1152 optval, optlen); 1153 case TCP_INQ: 1154 return mptcp_put_int_option(msk, optval, optlen, msk->recvmsg_inq); 1155 case TCP_CORK: 1156 return mptcp_put_int_option(msk, optval, optlen, msk->cork); 1157 case TCP_NODELAY: 1158 return mptcp_put_int_option(msk, optval, optlen, msk->nodelay); 1159 } 1160 return -EOPNOTSUPP; 1161 } 1162 1163 static int mptcp_getsockopt_v4(struct mptcp_sock *msk, int optname, 1164 char __user *optval, int __user *optlen) 1165 { 1166 struct sock *sk = (void *)msk; 1167 1168 switch (optname) { 1169 case IP_TOS: 1170 return mptcp_put_int_option(msk, optval, optlen, inet_sk(sk)->tos); 1171 } 1172 1173 return -EOPNOTSUPP; 1174 } 1175 1176 static int mptcp_getsockopt_sol_mptcp(struct mptcp_sock *msk, int optname, 1177 char __user *optval, int __user *optlen) 1178 { 1179 switch (optname) { 1180 case MPTCP_INFO: 1181 return mptcp_getsockopt_info(msk, optval, optlen); 1182 case MPTCP_TCPINFO: 1183 return mptcp_getsockopt_tcpinfo(msk, optval, optlen); 1184 case MPTCP_SUBFLOW_ADDRS: 1185 return mptcp_getsockopt_subflow_addrs(msk, optval, optlen); 1186 } 1187 1188 return -EOPNOTSUPP; 1189 } 1190 1191 int mptcp_getsockopt(struct sock *sk, int level, int optname, 1192 char __user *optval, int __user *option) 1193 { 1194 struct mptcp_sock *msk = mptcp_sk(sk); 1195 struct sock *ssk; 1196 1197 pr_debug("msk=%p", msk); 1198 1199 /* @@ the meaning of setsockopt() when the socket is connected and 1200 * there are multiple subflows is not yet defined. It is up to the 1201 * MPTCP-level socket to configure the subflows until the subflow 1202 * is in TCP fallback, when socket options are passed through 1203 * to the one remaining subflow. 1204 */ 1205 lock_sock(sk); 1206 ssk = __mptcp_tcp_fallback(msk); 1207 release_sock(sk); 1208 if (ssk) 1209 return tcp_getsockopt(ssk, level, optname, optval, option); 1210 1211 if (level == SOL_IP) 1212 return mptcp_getsockopt_v4(msk, optname, optval, option); 1213 if (level == SOL_TCP) 1214 return mptcp_getsockopt_sol_tcp(msk, optname, optval, option); 1215 if (level == SOL_MPTCP) 1216 return mptcp_getsockopt_sol_mptcp(msk, optname, optval, option); 1217 return -EOPNOTSUPP; 1218 } 1219 1220 static void sync_socket_options(struct mptcp_sock *msk, struct sock *ssk) 1221 { 1222 static const unsigned int tx_rx_locks = SOCK_RCVBUF_LOCK | SOCK_SNDBUF_LOCK; 1223 struct sock *sk = (struct sock *)msk; 1224 1225 if (ssk->sk_prot->keepalive) { 1226 if (sock_flag(sk, SOCK_KEEPOPEN)) 1227 ssk->sk_prot->keepalive(ssk, 1); 1228 else 1229 ssk->sk_prot->keepalive(ssk, 0); 1230 } 1231 1232 ssk->sk_priority = sk->sk_priority; 1233 ssk->sk_bound_dev_if = sk->sk_bound_dev_if; 1234 ssk->sk_incoming_cpu = sk->sk_incoming_cpu; 1235 __ip_sock_set_tos(ssk, inet_sk(sk)->tos); 1236 1237 if (sk->sk_userlocks & tx_rx_locks) { 1238 ssk->sk_userlocks |= sk->sk_userlocks & tx_rx_locks; 1239 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) 1240 WRITE_ONCE(ssk->sk_sndbuf, sk->sk_sndbuf); 1241 if (sk->sk_userlocks & SOCK_RCVBUF_LOCK) 1242 WRITE_ONCE(ssk->sk_rcvbuf, sk->sk_rcvbuf); 1243 } 1244 1245 if (sock_flag(sk, SOCK_LINGER)) { 1246 ssk->sk_lingertime = sk->sk_lingertime; 1247 sock_set_flag(ssk, SOCK_LINGER); 1248 } else { 1249 sock_reset_flag(ssk, SOCK_LINGER); 1250 } 1251 1252 if (sk->sk_mark != ssk->sk_mark) { 1253 ssk->sk_mark = sk->sk_mark; 1254 sk_dst_reset(ssk); 1255 } 1256 1257 sock_valbool_flag(ssk, SOCK_DBG, sock_flag(sk, SOCK_DBG)); 1258 1259 if (inet_csk(sk)->icsk_ca_ops != inet_csk(ssk)->icsk_ca_ops) 1260 tcp_set_congestion_control(ssk, msk->ca_name, false, true); 1261 __tcp_sock_set_cork(ssk, !!msk->cork); 1262 __tcp_sock_set_nodelay(ssk, !!msk->nodelay); 1263 1264 inet_sk(ssk)->transparent = inet_sk(sk)->transparent; 1265 inet_sk(ssk)->freebind = inet_sk(sk)->freebind; 1266 } 1267 1268 static void __mptcp_sockopt_sync(struct mptcp_sock *msk, struct sock *ssk) 1269 { 1270 bool slow = lock_sock_fast(ssk); 1271 1272 sync_socket_options(msk, ssk); 1273 1274 unlock_sock_fast(ssk, slow); 1275 } 1276 1277 void mptcp_sockopt_sync(struct mptcp_sock *msk, struct sock *ssk) 1278 { 1279 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 1280 1281 msk_owned_by_me(msk); 1282 1283 if (READ_ONCE(subflow->setsockopt_seq) != msk->setsockopt_seq) { 1284 __mptcp_sockopt_sync(msk, ssk); 1285 1286 subflow->setsockopt_seq = msk->setsockopt_seq; 1287 } 1288 } 1289 1290 void mptcp_sockopt_sync_locked(struct mptcp_sock *msk, struct sock *ssk) 1291 { 1292 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 1293 1294 msk_owned_by_me(msk); 1295 1296 if (READ_ONCE(subflow->setsockopt_seq) != msk->setsockopt_seq) { 1297 sync_socket_options(msk, ssk); 1298 1299 subflow->setsockopt_seq = msk->setsockopt_seq; 1300 } 1301 } 1302