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_BUSY_POLL: 347 case SO_PREFER_BUSY_POLL: 348 case SO_BUSY_POLL_BUDGET: 349 /* No need to copy: only relevant for msk */ 350 return sock_setsockopt(sk->sk_socket, SOL_SOCKET, optname, optval, optlen); 351 case SO_NO_CHECK: 352 case SO_DONTROUTE: 353 case SO_BROADCAST: 354 case SO_BSDCOMPAT: 355 case SO_PASSCRED: 356 case SO_PASSSEC: 357 case SO_RXQ_OVFL: 358 case SO_WIFI_STATUS: 359 case SO_NOFCS: 360 case SO_SELECT_ERR_QUEUE: 361 return 0; 362 } 363 364 /* SO_OOBINLINE is not supported, let's avoid the related mess 365 * SO_ATTACH_FILTER, SO_ATTACH_BPF, SO_ATTACH_REUSEPORT_CBPF, 366 * SO_DETACH_REUSEPORT_BPF, SO_DETACH_FILTER, SO_LOCK_FILTER, 367 * we must be careful with subflows 368 * 369 * SO_ATTACH_REUSEPORT_EBPF is not supported, at it checks 370 * explicitly the sk_protocol field 371 * 372 * SO_PEEK_OFF is unsupported, as it is for plain TCP 373 * SO_MAX_PACING_RATE is unsupported, we must be careful with subflows 374 * SO_CNX_ADVICE is currently unsupported, could possibly be relevant, 375 * but likely needs careful design 376 * 377 * SO_ZEROCOPY is currently unsupported, TODO in sndmsg 378 * SO_TXTIME is currently unsupported 379 */ 380 381 return -EOPNOTSUPP; 382 } 383 384 static int mptcp_setsockopt_v6(struct mptcp_sock *msk, int optname, 385 sockptr_t optval, unsigned int optlen) 386 { 387 struct sock *sk = (struct sock *)msk; 388 int ret = -EOPNOTSUPP; 389 struct socket *ssock; 390 391 switch (optname) { 392 case IPV6_V6ONLY: 393 case IPV6_TRANSPARENT: 394 case IPV6_FREEBIND: 395 lock_sock(sk); 396 ssock = __mptcp_nmpc_socket(msk); 397 if (!ssock) { 398 release_sock(sk); 399 return -EINVAL; 400 } 401 402 ret = tcp_setsockopt(ssock->sk, SOL_IPV6, optname, optval, optlen); 403 if (ret != 0) { 404 release_sock(sk); 405 return ret; 406 } 407 408 sockopt_seq_inc(msk); 409 410 switch (optname) { 411 case IPV6_V6ONLY: 412 sk->sk_ipv6only = ssock->sk->sk_ipv6only; 413 break; 414 case IPV6_TRANSPARENT: 415 inet_sk(sk)->transparent = inet_sk(ssock->sk)->transparent; 416 break; 417 case IPV6_FREEBIND: 418 inet_sk(sk)->freebind = inet_sk(ssock->sk)->freebind; 419 break; 420 } 421 422 release_sock(sk); 423 break; 424 } 425 426 return ret; 427 } 428 429 static bool mptcp_supported_sockopt(int level, int optname) 430 { 431 if (level == SOL_IP) { 432 switch (optname) { 433 /* should work fine */ 434 case IP_FREEBIND: 435 case IP_TRANSPARENT: 436 437 /* the following are control cmsg related */ 438 case IP_PKTINFO: 439 case IP_RECVTTL: 440 case IP_RECVTOS: 441 case IP_RECVOPTS: 442 case IP_RETOPTS: 443 case IP_PASSSEC: 444 case IP_RECVORIGDSTADDR: 445 case IP_CHECKSUM: 446 case IP_RECVFRAGSIZE: 447 448 /* common stuff that need some love */ 449 case IP_TOS: 450 case IP_TTL: 451 case IP_BIND_ADDRESS_NO_PORT: 452 case IP_MTU_DISCOVER: 453 case IP_RECVERR: 454 455 /* possibly less common may deserve some love */ 456 case IP_MINTTL: 457 458 /* the following is apparently a no-op for plain TCP */ 459 case IP_RECVERR_RFC4884: 460 return true; 461 } 462 463 /* IP_OPTIONS is not supported, needs subflow care */ 464 /* IP_HDRINCL, IP_NODEFRAG are not supported, RAW specific */ 465 /* IP_MULTICAST_TTL, IP_MULTICAST_LOOP, IP_UNICAST_IF, 466 * IP_ADD_MEMBERSHIP, IP_ADD_SOURCE_MEMBERSHIP, IP_DROP_MEMBERSHIP, 467 * IP_DROP_SOURCE_MEMBERSHIP, IP_BLOCK_SOURCE, IP_UNBLOCK_SOURCE, 468 * MCAST_JOIN_GROUP, MCAST_LEAVE_GROUP MCAST_JOIN_SOURCE_GROUP, 469 * MCAST_LEAVE_SOURCE_GROUP, MCAST_BLOCK_SOURCE, MCAST_UNBLOCK_SOURCE, 470 * MCAST_MSFILTER, IP_MULTICAST_ALL are not supported, better not deal 471 * with mcast stuff 472 */ 473 /* IP_IPSEC_POLICY, IP_XFRM_POLICY are nut supported, unrelated here */ 474 return false; 475 } 476 if (level == SOL_IPV6) { 477 switch (optname) { 478 case IPV6_V6ONLY: 479 480 /* the following are control cmsg related */ 481 case IPV6_RECVPKTINFO: 482 case IPV6_2292PKTINFO: 483 case IPV6_RECVHOPLIMIT: 484 case IPV6_2292HOPLIMIT: 485 case IPV6_RECVRTHDR: 486 case IPV6_2292RTHDR: 487 case IPV6_RECVHOPOPTS: 488 case IPV6_2292HOPOPTS: 489 case IPV6_RECVDSTOPTS: 490 case IPV6_2292DSTOPTS: 491 case IPV6_RECVTCLASS: 492 case IPV6_FLOWINFO: 493 case IPV6_RECVPATHMTU: 494 case IPV6_RECVORIGDSTADDR: 495 case IPV6_RECVFRAGSIZE: 496 497 /* the following ones need some love but are quite common */ 498 case IPV6_TCLASS: 499 case IPV6_TRANSPARENT: 500 case IPV6_FREEBIND: 501 case IPV6_PKTINFO: 502 case IPV6_2292PKTOPTIONS: 503 case IPV6_UNICAST_HOPS: 504 case IPV6_MTU_DISCOVER: 505 case IPV6_MTU: 506 case IPV6_RECVERR: 507 case IPV6_FLOWINFO_SEND: 508 case IPV6_FLOWLABEL_MGR: 509 case IPV6_MINHOPCOUNT: 510 case IPV6_DONTFRAG: 511 case IPV6_AUTOFLOWLABEL: 512 513 /* the following one is a no-op for plain TCP */ 514 case IPV6_RECVERR_RFC4884: 515 return true; 516 } 517 518 /* IPV6_HOPOPTS, IPV6_RTHDRDSTOPTS, IPV6_RTHDR, IPV6_DSTOPTS are 519 * not supported 520 */ 521 /* IPV6_MULTICAST_HOPS, IPV6_MULTICAST_LOOP, IPV6_UNICAST_IF, 522 * IPV6_MULTICAST_IF, IPV6_ADDRFORM, 523 * IPV6_ADD_MEMBERSHIP, IPV6_DROP_MEMBERSHIP, IPV6_JOIN_ANYCAST, 524 * IPV6_LEAVE_ANYCAST, IPV6_MULTICAST_ALL, MCAST_JOIN_GROUP, MCAST_LEAVE_GROUP, 525 * MCAST_JOIN_SOURCE_GROUP, MCAST_LEAVE_SOURCE_GROUP, 526 * MCAST_BLOCK_SOURCE, MCAST_UNBLOCK_SOURCE, MCAST_MSFILTER 527 * are not supported better not deal with mcast 528 */ 529 /* IPV6_ROUTER_ALERT, IPV6_ROUTER_ALERT_ISOLATE are not supported, since are evil */ 530 531 /* IPV6_IPSEC_POLICY, IPV6_XFRM_POLICY are not supported */ 532 /* IPV6_ADDR_PREFERENCES is not supported, we must be careful with subflows */ 533 return false; 534 } 535 if (level == SOL_TCP) { 536 switch (optname) { 537 /* the following are no-op or should work just fine */ 538 case TCP_THIN_DUPACK: 539 case TCP_DEFER_ACCEPT: 540 541 /* the following need some love */ 542 case TCP_MAXSEG: 543 case TCP_NODELAY: 544 case TCP_THIN_LINEAR_TIMEOUTS: 545 case TCP_CONGESTION: 546 case TCP_ULP: 547 case TCP_CORK: 548 case TCP_KEEPIDLE: 549 case TCP_KEEPINTVL: 550 case TCP_KEEPCNT: 551 case TCP_SYNCNT: 552 case TCP_SAVE_SYN: 553 case TCP_LINGER2: 554 case TCP_WINDOW_CLAMP: 555 case TCP_QUICKACK: 556 case TCP_USER_TIMEOUT: 557 case TCP_TIMESTAMP: 558 case TCP_NOTSENT_LOWAT: 559 case TCP_TX_DELAY: 560 return true; 561 } 562 563 /* TCP_MD5SIG, TCP_MD5SIG_EXT are not supported, MD5 is not compatible with MPTCP */ 564 565 /* TCP_REPAIR, TCP_REPAIR_QUEUE, TCP_QUEUE_SEQ, TCP_REPAIR_OPTIONS, 566 * TCP_REPAIR_WINDOW are not supported, better avoid this mess 567 */ 568 /* TCP_FASTOPEN_KEY, TCP_FASTOPEN TCP_FASTOPEN_CONNECT, TCP_FASTOPEN_NO_COOKIE, 569 * are not supported fastopen is currently unsupported 570 */ 571 /* TCP_INQ is currently unsupported, needs some recvmsg work */ 572 } 573 return false; 574 } 575 576 static int mptcp_setsockopt_sol_tcp_congestion(struct mptcp_sock *msk, sockptr_t optval, 577 unsigned int optlen) 578 { 579 struct mptcp_subflow_context *subflow; 580 struct sock *sk = (struct sock *)msk; 581 char name[TCP_CA_NAME_MAX]; 582 bool cap_net_admin; 583 int ret; 584 585 if (optlen < 1) 586 return -EINVAL; 587 588 ret = strncpy_from_sockptr(name, optval, 589 min_t(long, TCP_CA_NAME_MAX - 1, optlen)); 590 if (ret < 0) 591 return -EFAULT; 592 593 name[ret] = 0; 594 595 cap_net_admin = ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN); 596 597 ret = 0; 598 lock_sock(sk); 599 sockopt_seq_inc(msk); 600 mptcp_for_each_subflow(msk, subflow) { 601 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 602 int err; 603 604 lock_sock(ssk); 605 err = tcp_set_congestion_control(ssk, name, true, cap_net_admin); 606 if (err < 0 && ret == 0) 607 ret = err; 608 subflow->setsockopt_seq = msk->setsockopt_seq; 609 release_sock(ssk); 610 } 611 612 if (ret == 0) 613 strcpy(msk->ca_name, name); 614 615 release_sock(sk); 616 return ret; 617 } 618 619 static int mptcp_setsockopt_sol_ip_set_transparent(struct mptcp_sock *msk, int optname, 620 sockptr_t optval, unsigned int optlen) 621 { 622 struct sock *sk = (struct sock *)msk; 623 struct inet_sock *issk; 624 struct socket *ssock; 625 int err; 626 627 err = ip_setsockopt(sk, SOL_IP, optname, optval, optlen); 628 if (err != 0) 629 return err; 630 631 lock_sock(sk); 632 633 ssock = __mptcp_nmpc_socket(msk); 634 if (!ssock) { 635 release_sock(sk); 636 return -EINVAL; 637 } 638 639 issk = inet_sk(ssock->sk); 640 641 switch (optname) { 642 case IP_FREEBIND: 643 issk->freebind = inet_sk(sk)->freebind; 644 break; 645 case IP_TRANSPARENT: 646 issk->transparent = inet_sk(sk)->transparent; 647 break; 648 default: 649 release_sock(sk); 650 WARN_ON_ONCE(1); 651 return -EOPNOTSUPP; 652 } 653 654 sockopt_seq_inc(msk); 655 release_sock(sk); 656 return 0; 657 } 658 659 static int mptcp_setsockopt_v4_set_tos(struct mptcp_sock *msk, int optname, 660 sockptr_t optval, unsigned int optlen) 661 { 662 struct mptcp_subflow_context *subflow; 663 struct sock *sk = (struct sock *)msk; 664 int err, val; 665 666 err = ip_setsockopt(sk, SOL_IP, optname, optval, optlen); 667 668 if (err != 0) 669 return err; 670 671 lock_sock(sk); 672 sockopt_seq_inc(msk); 673 val = inet_sk(sk)->tos; 674 mptcp_for_each_subflow(msk, subflow) { 675 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 676 677 __ip_sock_set_tos(ssk, val); 678 } 679 release_sock(sk); 680 681 return err; 682 } 683 684 static int mptcp_setsockopt_v4(struct mptcp_sock *msk, int optname, 685 sockptr_t optval, unsigned int optlen) 686 { 687 switch (optname) { 688 case IP_FREEBIND: 689 case IP_TRANSPARENT: 690 return mptcp_setsockopt_sol_ip_set_transparent(msk, optname, optval, optlen); 691 case IP_TOS: 692 return mptcp_setsockopt_v4_set_tos(msk, optname, optval, optlen); 693 } 694 695 return -EOPNOTSUPP; 696 } 697 698 static int mptcp_setsockopt_sol_tcp(struct mptcp_sock *msk, int optname, 699 sockptr_t optval, unsigned int optlen) 700 { 701 switch (optname) { 702 case TCP_ULP: 703 return -EOPNOTSUPP; 704 case TCP_CONGESTION: 705 return mptcp_setsockopt_sol_tcp_congestion(msk, optval, optlen); 706 } 707 708 return -EOPNOTSUPP; 709 } 710 711 int mptcp_setsockopt(struct sock *sk, int level, int optname, 712 sockptr_t optval, unsigned int optlen) 713 { 714 struct mptcp_sock *msk = mptcp_sk(sk); 715 struct sock *ssk; 716 717 pr_debug("msk=%p", msk); 718 719 if (level == SOL_SOCKET) 720 return mptcp_setsockopt_sol_socket(msk, optname, optval, optlen); 721 722 if (!mptcp_supported_sockopt(level, optname)) 723 return -ENOPROTOOPT; 724 725 /* @@ the meaning of setsockopt() when the socket is connected and 726 * there are multiple subflows is not yet defined. It is up to the 727 * MPTCP-level socket to configure the subflows until the subflow 728 * is in TCP fallback, when TCP socket options are passed through 729 * to the one remaining subflow. 730 */ 731 lock_sock(sk); 732 ssk = __mptcp_tcp_fallback(msk); 733 release_sock(sk); 734 if (ssk) 735 return tcp_setsockopt(ssk, level, optname, optval, optlen); 736 737 if (level == SOL_IP) 738 return mptcp_setsockopt_v4(msk, optname, optval, optlen); 739 740 if (level == SOL_IPV6) 741 return mptcp_setsockopt_v6(msk, optname, optval, optlen); 742 743 if (level == SOL_TCP) 744 return mptcp_setsockopt_sol_tcp(msk, optname, optval, optlen); 745 746 return -EOPNOTSUPP; 747 } 748 749 static int mptcp_getsockopt_first_sf_only(struct mptcp_sock *msk, int level, int optname, 750 char __user *optval, int __user *optlen) 751 { 752 struct sock *sk = (struct sock *)msk; 753 struct socket *ssock; 754 int ret = -EINVAL; 755 struct sock *ssk; 756 757 lock_sock(sk); 758 ssk = msk->first; 759 if (ssk) { 760 ret = tcp_getsockopt(ssk, level, optname, optval, optlen); 761 goto out; 762 } 763 764 ssock = __mptcp_nmpc_socket(msk); 765 if (!ssock) 766 goto out; 767 768 ret = tcp_getsockopt(ssock->sk, level, optname, optval, optlen); 769 770 out: 771 release_sock(sk); 772 return ret; 773 } 774 775 void mptcp_diag_fill_info(struct mptcp_sock *msk, struct mptcp_info *info) 776 { 777 struct sock *sk = &msk->sk.icsk_inet.sk; 778 u32 flags = 0; 779 bool slow; 780 u8 val; 781 782 memset(info, 0, sizeof(*info)); 783 784 slow = lock_sock_fast(sk); 785 786 info->mptcpi_subflows = READ_ONCE(msk->pm.subflows); 787 info->mptcpi_add_addr_signal = READ_ONCE(msk->pm.add_addr_signaled); 788 info->mptcpi_add_addr_accepted = READ_ONCE(msk->pm.add_addr_accepted); 789 info->mptcpi_local_addr_used = READ_ONCE(msk->pm.local_addr_used); 790 info->mptcpi_subflows_max = mptcp_pm_get_subflows_max(msk); 791 val = mptcp_pm_get_add_addr_signal_max(msk); 792 info->mptcpi_add_addr_signal_max = val; 793 val = mptcp_pm_get_add_addr_accept_max(msk); 794 info->mptcpi_add_addr_accepted_max = val; 795 info->mptcpi_local_addr_max = mptcp_pm_get_local_addr_max(msk); 796 if (test_bit(MPTCP_FALLBACK_DONE, &msk->flags)) 797 flags |= MPTCP_INFO_FLAG_FALLBACK; 798 if (READ_ONCE(msk->can_ack)) 799 flags |= MPTCP_INFO_FLAG_REMOTE_KEY_RECEIVED; 800 info->mptcpi_flags = flags; 801 info->mptcpi_token = READ_ONCE(msk->token); 802 info->mptcpi_write_seq = READ_ONCE(msk->write_seq); 803 info->mptcpi_snd_una = READ_ONCE(msk->snd_una); 804 info->mptcpi_rcv_nxt = READ_ONCE(msk->ack_seq); 805 info->mptcpi_csum_enabled = READ_ONCE(msk->csum_enabled); 806 807 unlock_sock_fast(sk, slow); 808 } 809 EXPORT_SYMBOL_GPL(mptcp_diag_fill_info); 810 811 static int mptcp_getsockopt_info(struct mptcp_sock *msk, char __user *optval, int __user *optlen) 812 { 813 struct mptcp_info m_info; 814 int len; 815 816 if (get_user(len, optlen)) 817 return -EFAULT; 818 819 len = min_t(unsigned int, len, sizeof(struct mptcp_info)); 820 821 mptcp_diag_fill_info(msk, &m_info); 822 823 if (put_user(len, optlen)) 824 return -EFAULT; 825 826 if (copy_to_user(optval, &m_info, len)) 827 return -EFAULT; 828 829 return 0; 830 } 831 832 static int mptcp_put_subflow_data(struct mptcp_subflow_data *sfd, 833 char __user *optval, 834 u32 copied, 835 int __user *optlen) 836 { 837 u32 copylen = min_t(u32, sfd->size_subflow_data, sizeof(*sfd)); 838 839 if (copied) 840 copied += sfd->size_subflow_data; 841 else 842 copied = copylen; 843 844 if (put_user(copied, optlen)) 845 return -EFAULT; 846 847 if (copy_to_user(optval, sfd, copylen)) 848 return -EFAULT; 849 850 return 0; 851 } 852 853 static int mptcp_get_subflow_data(struct mptcp_subflow_data *sfd, 854 char __user *optval, int __user *optlen) 855 { 856 int len, copylen; 857 858 if (get_user(len, optlen)) 859 return -EFAULT; 860 861 /* if mptcp_subflow_data size is changed, need to adjust 862 * this function to deal with programs using old version. 863 */ 864 BUILD_BUG_ON(sizeof(*sfd) != MIN_INFO_OPTLEN_SIZE); 865 866 if (len < MIN_INFO_OPTLEN_SIZE) 867 return -EINVAL; 868 869 memset(sfd, 0, sizeof(*sfd)); 870 871 copylen = min_t(unsigned int, len, sizeof(*sfd)); 872 if (copy_from_user(sfd, optval, copylen)) 873 return -EFAULT; 874 875 /* size_subflow_data is u32, but len is signed */ 876 if (sfd->size_subflow_data > INT_MAX || 877 sfd->size_user > INT_MAX) 878 return -EINVAL; 879 880 if (sfd->size_subflow_data < MIN_INFO_OPTLEN_SIZE || 881 sfd->size_subflow_data > len) 882 return -EINVAL; 883 884 if (sfd->num_subflows || sfd->size_kernel) 885 return -EINVAL; 886 887 return len - sfd->size_subflow_data; 888 } 889 890 static int mptcp_getsockopt_tcpinfo(struct mptcp_sock *msk, char __user *optval, 891 int __user *optlen) 892 { 893 struct mptcp_subflow_context *subflow; 894 struct sock *sk = &msk->sk.icsk_inet.sk; 895 unsigned int sfcount = 0, copied = 0; 896 struct mptcp_subflow_data sfd; 897 char __user *infoptr; 898 int len; 899 900 len = mptcp_get_subflow_data(&sfd, optval, optlen); 901 if (len < 0) 902 return len; 903 904 sfd.size_kernel = sizeof(struct tcp_info); 905 sfd.size_user = min_t(unsigned int, sfd.size_user, 906 sizeof(struct tcp_info)); 907 908 infoptr = optval + sfd.size_subflow_data; 909 910 lock_sock(sk); 911 912 mptcp_for_each_subflow(msk, subflow) { 913 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 914 915 ++sfcount; 916 917 if (len && len >= sfd.size_user) { 918 struct tcp_info info; 919 920 tcp_get_info(ssk, &info); 921 922 if (copy_to_user(infoptr, &info, sfd.size_user)) { 923 release_sock(sk); 924 return -EFAULT; 925 } 926 927 infoptr += sfd.size_user; 928 copied += sfd.size_user; 929 len -= sfd.size_user; 930 } 931 } 932 933 release_sock(sk); 934 935 sfd.num_subflows = sfcount; 936 937 if (mptcp_put_subflow_data(&sfd, optval, copied, optlen)) 938 return -EFAULT; 939 940 return 0; 941 } 942 943 static void mptcp_get_sub_addrs(const struct sock *sk, struct mptcp_subflow_addrs *a) 944 { 945 struct inet_sock *inet = inet_sk(sk); 946 947 memset(a, 0, sizeof(*a)); 948 949 if (sk->sk_family == AF_INET) { 950 a->sin_local.sin_family = AF_INET; 951 a->sin_local.sin_port = inet->inet_sport; 952 a->sin_local.sin_addr.s_addr = inet->inet_rcv_saddr; 953 954 if (!a->sin_local.sin_addr.s_addr) 955 a->sin_local.sin_addr.s_addr = inet->inet_saddr; 956 957 a->sin_remote.sin_family = AF_INET; 958 a->sin_remote.sin_port = inet->inet_dport; 959 a->sin_remote.sin_addr.s_addr = inet->inet_daddr; 960 #if IS_ENABLED(CONFIG_IPV6) 961 } else if (sk->sk_family == AF_INET6) { 962 const struct ipv6_pinfo *np = inet6_sk(sk); 963 964 if (WARN_ON_ONCE(!np)) 965 return; 966 967 a->sin6_local.sin6_family = AF_INET6; 968 a->sin6_local.sin6_port = inet->inet_sport; 969 970 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr)) 971 a->sin6_local.sin6_addr = np->saddr; 972 else 973 a->sin6_local.sin6_addr = sk->sk_v6_rcv_saddr; 974 975 a->sin6_remote.sin6_family = AF_INET6; 976 a->sin6_remote.sin6_port = inet->inet_dport; 977 a->sin6_remote.sin6_addr = sk->sk_v6_daddr; 978 #endif 979 } 980 } 981 982 static int mptcp_getsockopt_subflow_addrs(struct mptcp_sock *msk, char __user *optval, 983 int __user *optlen) 984 { 985 struct sock *sk = &msk->sk.icsk_inet.sk; 986 struct mptcp_subflow_context *subflow; 987 unsigned int sfcount = 0, copied = 0; 988 struct mptcp_subflow_data sfd; 989 char __user *addrptr; 990 int len; 991 992 len = mptcp_get_subflow_data(&sfd, optval, optlen); 993 if (len < 0) 994 return len; 995 996 sfd.size_kernel = sizeof(struct mptcp_subflow_addrs); 997 sfd.size_user = min_t(unsigned int, sfd.size_user, 998 sizeof(struct mptcp_subflow_addrs)); 999 1000 addrptr = optval + sfd.size_subflow_data; 1001 1002 lock_sock(sk); 1003 1004 mptcp_for_each_subflow(msk, subflow) { 1005 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 1006 1007 ++sfcount; 1008 1009 if (len && len >= sfd.size_user) { 1010 struct mptcp_subflow_addrs a; 1011 1012 mptcp_get_sub_addrs(ssk, &a); 1013 1014 if (copy_to_user(addrptr, &a, sfd.size_user)) { 1015 release_sock(sk); 1016 return -EFAULT; 1017 } 1018 1019 addrptr += sfd.size_user; 1020 copied += sfd.size_user; 1021 len -= sfd.size_user; 1022 } 1023 } 1024 1025 release_sock(sk); 1026 1027 sfd.num_subflows = sfcount; 1028 1029 if (mptcp_put_subflow_data(&sfd, optval, copied, optlen)) 1030 return -EFAULT; 1031 1032 return 0; 1033 } 1034 1035 static int mptcp_getsockopt_sol_tcp(struct mptcp_sock *msk, int optname, 1036 char __user *optval, int __user *optlen) 1037 { 1038 switch (optname) { 1039 case TCP_ULP: 1040 case TCP_CONGESTION: 1041 case TCP_INFO: 1042 case TCP_CC_INFO: 1043 return mptcp_getsockopt_first_sf_only(msk, SOL_TCP, optname, 1044 optval, optlen); 1045 } 1046 return -EOPNOTSUPP; 1047 } 1048 1049 static int mptcp_getsockopt_sol_mptcp(struct mptcp_sock *msk, int optname, 1050 char __user *optval, int __user *optlen) 1051 { 1052 switch (optname) { 1053 case MPTCP_INFO: 1054 return mptcp_getsockopt_info(msk, optval, optlen); 1055 case MPTCP_TCPINFO: 1056 return mptcp_getsockopt_tcpinfo(msk, optval, optlen); 1057 case MPTCP_SUBFLOW_ADDRS: 1058 return mptcp_getsockopt_subflow_addrs(msk, optval, optlen); 1059 } 1060 1061 return -EOPNOTSUPP; 1062 } 1063 1064 int mptcp_getsockopt(struct sock *sk, int level, int optname, 1065 char __user *optval, int __user *option) 1066 { 1067 struct mptcp_sock *msk = mptcp_sk(sk); 1068 struct sock *ssk; 1069 1070 pr_debug("msk=%p", msk); 1071 1072 /* @@ the meaning of setsockopt() when the socket is connected and 1073 * there are multiple subflows is not yet defined. It is up to the 1074 * MPTCP-level socket to configure the subflows until the subflow 1075 * is in TCP fallback, when socket options are passed through 1076 * to the one remaining subflow. 1077 */ 1078 lock_sock(sk); 1079 ssk = __mptcp_tcp_fallback(msk); 1080 release_sock(sk); 1081 if (ssk) 1082 return tcp_getsockopt(ssk, level, optname, optval, option); 1083 1084 if (level == SOL_TCP) 1085 return mptcp_getsockopt_sol_tcp(msk, optname, optval, option); 1086 if (level == SOL_MPTCP) 1087 return mptcp_getsockopt_sol_mptcp(msk, optname, optval, option); 1088 return -EOPNOTSUPP; 1089 } 1090 1091 static void sync_socket_options(struct mptcp_sock *msk, struct sock *ssk) 1092 { 1093 static const unsigned int tx_rx_locks = SOCK_RCVBUF_LOCK | SOCK_SNDBUF_LOCK; 1094 struct sock *sk = (struct sock *)msk; 1095 1096 if (ssk->sk_prot->keepalive) { 1097 if (sock_flag(sk, SOCK_KEEPOPEN)) 1098 ssk->sk_prot->keepalive(ssk, 1); 1099 else 1100 ssk->sk_prot->keepalive(ssk, 0); 1101 } 1102 1103 ssk->sk_priority = sk->sk_priority; 1104 ssk->sk_bound_dev_if = sk->sk_bound_dev_if; 1105 ssk->sk_incoming_cpu = sk->sk_incoming_cpu; 1106 __ip_sock_set_tos(ssk, inet_sk(sk)->tos); 1107 1108 if (sk->sk_userlocks & tx_rx_locks) { 1109 ssk->sk_userlocks |= sk->sk_userlocks & tx_rx_locks; 1110 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) 1111 WRITE_ONCE(ssk->sk_sndbuf, sk->sk_sndbuf); 1112 if (sk->sk_userlocks & SOCK_RCVBUF_LOCK) 1113 WRITE_ONCE(ssk->sk_rcvbuf, sk->sk_rcvbuf); 1114 } 1115 1116 if (sock_flag(sk, SOCK_LINGER)) { 1117 ssk->sk_lingertime = sk->sk_lingertime; 1118 sock_set_flag(ssk, SOCK_LINGER); 1119 } else { 1120 sock_reset_flag(ssk, SOCK_LINGER); 1121 } 1122 1123 if (sk->sk_mark != ssk->sk_mark) { 1124 ssk->sk_mark = sk->sk_mark; 1125 sk_dst_reset(ssk); 1126 } 1127 1128 sock_valbool_flag(ssk, SOCK_DBG, sock_flag(sk, SOCK_DBG)); 1129 1130 if (inet_csk(sk)->icsk_ca_ops != inet_csk(ssk)->icsk_ca_ops) 1131 tcp_set_congestion_control(ssk, msk->ca_name, false, true); 1132 1133 inet_sk(ssk)->transparent = inet_sk(sk)->transparent; 1134 inet_sk(ssk)->freebind = inet_sk(sk)->freebind; 1135 } 1136 1137 static void __mptcp_sockopt_sync(struct mptcp_sock *msk, struct sock *ssk) 1138 { 1139 bool slow = lock_sock_fast(ssk); 1140 1141 sync_socket_options(msk, ssk); 1142 1143 unlock_sock_fast(ssk, slow); 1144 } 1145 1146 void mptcp_sockopt_sync(struct mptcp_sock *msk, struct sock *ssk) 1147 { 1148 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 1149 1150 msk_owned_by_me(msk); 1151 1152 if (READ_ONCE(subflow->setsockopt_seq) != msk->setsockopt_seq) { 1153 __mptcp_sockopt_sync(msk, ssk); 1154 1155 subflow->setsockopt_seq = msk->setsockopt_seq; 1156 } 1157 } 1158 1159 void mptcp_sockopt_sync_all(struct mptcp_sock *msk) 1160 { 1161 struct mptcp_subflow_context *subflow; 1162 struct sock *sk = (struct sock *)msk; 1163 u32 seq; 1164 1165 seq = sockopt_seq_reset(sk); 1166 1167 mptcp_for_each_subflow(msk, subflow) { 1168 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 1169 u32 sseq = READ_ONCE(subflow->setsockopt_seq); 1170 1171 if (sseq != msk->setsockopt_seq) { 1172 __mptcp_sockopt_sync(msk, ssk); 1173 WRITE_ONCE(subflow->setsockopt_seq, seq); 1174 } else if (sseq != seq) { 1175 WRITE_ONCE(subflow->setsockopt_seq, seq); 1176 } 1177 1178 cond_resched(); 1179 } 1180 1181 msk->setsockopt_seq = seq; 1182 } 1183