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 static struct sock *__mptcp_tcp_fallback(struct mptcp_sock *msk) 18 { 19 sock_owned_by_me((const struct sock *)msk); 20 21 if (likely(!__mptcp_check_fallback(msk))) 22 return NULL; 23 24 return msk->first; 25 } 26 27 static u32 sockopt_seq_reset(const struct sock *sk) 28 { 29 sock_owned_by_me(sk); 30 31 /* Highbits contain state. Allows to distinguish sockopt_seq 32 * of listener and established: 33 * s0 = new_listener() 34 * sockopt(s0) - seq is 1 35 * s1 = accept(s0) - s1 inherits seq 1 if listener sk (s0) 36 * sockopt(s0) - seq increments to 2 on s0 37 * sockopt(s1) // seq increments to 2 on s1 (different option) 38 * new ssk completes join, inherits options from s0 // seq 2 39 * Needs sync from mptcp join logic, but ssk->seq == msk->seq 40 * 41 * Set High order bits to sk_state so ssk->seq == msk->seq test 42 * will fail. 43 */ 44 45 return (u32)sk->sk_state << 24u; 46 } 47 48 static void sockopt_seq_inc(struct mptcp_sock *msk) 49 { 50 u32 seq = (msk->setsockopt_seq + 1) & 0x00ffffff; 51 52 msk->setsockopt_seq = sockopt_seq_reset((struct sock *)msk) + seq; 53 } 54 55 static int mptcp_get_int_option(struct mptcp_sock *msk, sockptr_t optval, 56 unsigned int optlen, int *val) 57 { 58 if (optlen < sizeof(int)) 59 return -EINVAL; 60 61 if (copy_from_sockptr(val, optval, sizeof(*val))) 62 return -EFAULT; 63 64 return 0; 65 } 66 67 static void mptcp_sol_socket_sync_intval(struct mptcp_sock *msk, int optname, int val) 68 { 69 struct mptcp_subflow_context *subflow; 70 struct sock *sk = (struct sock *)msk; 71 72 lock_sock(sk); 73 sockopt_seq_inc(msk); 74 75 mptcp_for_each_subflow(msk, subflow) { 76 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 77 bool slow = lock_sock_fast(ssk); 78 79 switch (optname) { 80 case SO_DEBUG: 81 sock_valbool_flag(ssk, SOCK_DBG, !!val); 82 break; 83 case SO_KEEPALIVE: 84 if (ssk->sk_prot->keepalive) 85 ssk->sk_prot->keepalive(ssk, !!val); 86 sock_valbool_flag(ssk, SOCK_KEEPOPEN, !!val); 87 break; 88 case SO_PRIORITY: 89 ssk->sk_priority = val; 90 break; 91 case SO_SNDBUF: 92 case SO_SNDBUFFORCE: 93 ssk->sk_userlocks |= SOCK_SNDBUF_LOCK; 94 WRITE_ONCE(ssk->sk_sndbuf, sk->sk_sndbuf); 95 break; 96 case SO_RCVBUF: 97 case SO_RCVBUFFORCE: 98 ssk->sk_userlocks |= SOCK_RCVBUF_LOCK; 99 WRITE_ONCE(ssk->sk_rcvbuf, sk->sk_rcvbuf); 100 break; 101 case SO_MARK: 102 if (READ_ONCE(ssk->sk_mark) != sk->sk_mark) { 103 ssk->sk_mark = sk->sk_mark; 104 sk_dst_reset(ssk); 105 } 106 break; 107 case SO_INCOMING_CPU: 108 WRITE_ONCE(ssk->sk_incoming_cpu, val); 109 break; 110 } 111 112 subflow->setsockopt_seq = msk->setsockopt_seq; 113 unlock_sock_fast(ssk, slow); 114 } 115 116 release_sock(sk); 117 } 118 119 static int mptcp_sol_socket_intval(struct mptcp_sock *msk, int optname, int val) 120 { 121 sockptr_t optval = KERNEL_SOCKPTR(&val); 122 struct sock *sk = (struct sock *)msk; 123 int ret; 124 125 ret = sock_setsockopt(sk->sk_socket, SOL_SOCKET, optname, 126 optval, sizeof(val)); 127 if (ret) 128 return ret; 129 130 mptcp_sol_socket_sync_intval(msk, optname, val); 131 return 0; 132 } 133 134 static void mptcp_so_incoming_cpu(struct mptcp_sock *msk, int val) 135 { 136 struct sock *sk = (struct sock *)msk; 137 138 WRITE_ONCE(sk->sk_incoming_cpu, val); 139 140 mptcp_sol_socket_sync_intval(msk, SO_INCOMING_CPU, val); 141 } 142 143 static int mptcp_setsockopt_sol_socket_tstamp(struct mptcp_sock *msk, int optname, int val) 144 { 145 sockptr_t optval = KERNEL_SOCKPTR(&val); 146 struct mptcp_subflow_context *subflow; 147 struct sock *sk = (struct sock *)msk; 148 int ret; 149 150 ret = sock_setsockopt(sk->sk_socket, SOL_SOCKET, optname, 151 optval, sizeof(val)); 152 if (ret) 153 return ret; 154 155 lock_sock(sk); 156 mptcp_for_each_subflow(msk, subflow) { 157 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 158 bool slow = lock_sock_fast(ssk); 159 160 switch (optname) { 161 case SO_TIMESTAMP_OLD: 162 case SO_TIMESTAMP_NEW: 163 case SO_TIMESTAMPNS_OLD: 164 case SO_TIMESTAMPNS_NEW: 165 sock_set_timestamp(sk, optname, !!val); 166 break; 167 case SO_TIMESTAMPING_NEW: 168 case SO_TIMESTAMPING_OLD: 169 sock_set_timestamping(sk, optname, val); 170 break; 171 } 172 173 unlock_sock_fast(ssk, slow); 174 } 175 176 release_sock(sk); 177 return 0; 178 } 179 180 static int mptcp_setsockopt_sol_socket_int(struct mptcp_sock *msk, int optname, 181 sockptr_t optval, unsigned int optlen) 182 { 183 int val, ret; 184 185 ret = mptcp_get_int_option(msk, optval, optlen, &val); 186 if (ret) 187 return ret; 188 189 switch (optname) { 190 case SO_KEEPALIVE: 191 mptcp_sol_socket_sync_intval(msk, optname, val); 192 return 0; 193 case SO_DEBUG: 194 case SO_MARK: 195 case SO_PRIORITY: 196 case SO_SNDBUF: 197 case SO_SNDBUFFORCE: 198 case SO_RCVBUF: 199 case SO_RCVBUFFORCE: 200 return mptcp_sol_socket_intval(msk, optname, val); 201 case SO_INCOMING_CPU: 202 mptcp_so_incoming_cpu(msk, val); 203 return 0; 204 case SO_TIMESTAMP_OLD: 205 case SO_TIMESTAMP_NEW: 206 case SO_TIMESTAMPNS_OLD: 207 case SO_TIMESTAMPNS_NEW: 208 case SO_TIMESTAMPING_OLD: 209 case SO_TIMESTAMPING_NEW: 210 return mptcp_setsockopt_sol_socket_tstamp(msk, optname, val); 211 } 212 213 return -ENOPROTOOPT; 214 } 215 216 static int mptcp_setsockopt_sol_socket_linger(struct mptcp_sock *msk, sockptr_t optval, 217 unsigned int optlen) 218 { 219 struct mptcp_subflow_context *subflow; 220 struct sock *sk = (struct sock *)msk; 221 struct linger ling; 222 sockptr_t kopt; 223 int ret; 224 225 if (optlen < sizeof(ling)) 226 return -EINVAL; 227 228 if (copy_from_sockptr(&ling, optval, sizeof(ling))) 229 return -EFAULT; 230 231 kopt = KERNEL_SOCKPTR(&ling); 232 ret = sock_setsockopt(sk->sk_socket, SOL_SOCKET, SO_LINGER, kopt, sizeof(ling)); 233 if (ret) 234 return ret; 235 236 lock_sock(sk); 237 sockopt_seq_inc(msk); 238 mptcp_for_each_subflow(msk, subflow) { 239 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 240 bool slow = lock_sock_fast(ssk); 241 242 if (!ling.l_onoff) { 243 sock_reset_flag(ssk, SOCK_LINGER); 244 } else { 245 ssk->sk_lingertime = sk->sk_lingertime; 246 sock_set_flag(ssk, SOCK_LINGER); 247 } 248 249 subflow->setsockopt_seq = msk->setsockopt_seq; 250 unlock_sock_fast(ssk, slow); 251 } 252 253 release_sock(sk); 254 return 0; 255 } 256 257 static int mptcp_setsockopt_sol_socket(struct mptcp_sock *msk, int optname, 258 sockptr_t optval, unsigned int optlen) 259 { 260 struct sock *sk = (struct sock *)msk; 261 struct socket *ssock; 262 int ret; 263 264 switch (optname) { 265 case SO_REUSEPORT: 266 case SO_REUSEADDR: 267 case SO_BINDTODEVICE: 268 case SO_BINDTOIFINDEX: 269 lock_sock(sk); 270 ssock = __mptcp_nmpc_socket(msk); 271 if (!ssock) { 272 release_sock(sk); 273 return -EINVAL; 274 } 275 276 ret = sock_setsockopt(ssock, SOL_SOCKET, optname, optval, optlen); 277 if (ret == 0) { 278 if (optname == SO_REUSEPORT) 279 sk->sk_reuseport = ssock->sk->sk_reuseport; 280 else if (optname == SO_REUSEADDR) 281 sk->sk_reuse = ssock->sk->sk_reuse; 282 else if (optname == SO_BINDTODEVICE) 283 sk->sk_bound_dev_if = ssock->sk->sk_bound_dev_if; 284 else if (optname == SO_BINDTOIFINDEX) 285 sk->sk_bound_dev_if = ssock->sk->sk_bound_dev_if; 286 } 287 release_sock(sk); 288 return ret; 289 case SO_KEEPALIVE: 290 case SO_PRIORITY: 291 case SO_SNDBUF: 292 case SO_SNDBUFFORCE: 293 case SO_RCVBUF: 294 case SO_RCVBUFFORCE: 295 case SO_MARK: 296 case SO_INCOMING_CPU: 297 case SO_DEBUG: 298 case SO_TIMESTAMP_OLD: 299 case SO_TIMESTAMP_NEW: 300 case SO_TIMESTAMPNS_OLD: 301 case SO_TIMESTAMPNS_NEW: 302 case SO_TIMESTAMPING_OLD: 303 case SO_TIMESTAMPING_NEW: 304 return mptcp_setsockopt_sol_socket_int(msk, optname, optval, optlen); 305 case SO_LINGER: 306 return mptcp_setsockopt_sol_socket_linger(msk, optval, optlen); 307 case SO_RCVLOWAT: 308 case SO_RCVTIMEO_OLD: 309 case SO_RCVTIMEO_NEW: 310 case SO_BUSY_POLL: 311 case SO_PREFER_BUSY_POLL: 312 case SO_BUSY_POLL_BUDGET: 313 /* No need to copy: only relevant for msk */ 314 return sock_setsockopt(sk->sk_socket, SOL_SOCKET, optname, optval, optlen); 315 case SO_NO_CHECK: 316 case SO_DONTROUTE: 317 case SO_BROADCAST: 318 case SO_BSDCOMPAT: 319 case SO_PASSCRED: 320 case SO_PASSSEC: 321 case SO_RXQ_OVFL: 322 case SO_WIFI_STATUS: 323 case SO_NOFCS: 324 case SO_SELECT_ERR_QUEUE: 325 return 0; 326 } 327 328 /* SO_OOBINLINE is not supported, let's avoid the related mess 329 * SO_ATTACH_FILTER, SO_ATTACH_BPF, SO_ATTACH_REUSEPORT_CBPF, 330 * SO_DETACH_REUSEPORT_BPF, SO_DETACH_FILTER, SO_LOCK_FILTER, 331 * we must be careful with subflows 332 * 333 * SO_ATTACH_REUSEPORT_EBPF is not supported, at it checks 334 * explicitly the sk_protocol field 335 * 336 * SO_PEEK_OFF is unsupported, as it is for plain TCP 337 * SO_MAX_PACING_RATE is unsupported, we must be careful with subflows 338 * SO_CNX_ADVICE is currently unsupported, could possibly be relevant, 339 * but likely needs careful design 340 * 341 * SO_ZEROCOPY is currently unsupported, TODO in sndmsg 342 * SO_TXTIME is currently unsupported 343 */ 344 345 return -EOPNOTSUPP; 346 } 347 348 static int mptcp_setsockopt_v6(struct mptcp_sock *msk, int optname, 349 sockptr_t optval, unsigned int optlen) 350 { 351 struct sock *sk = (struct sock *)msk; 352 int ret = -EOPNOTSUPP; 353 struct socket *ssock; 354 355 switch (optname) { 356 case IPV6_V6ONLY: 357 lock_sock(sk); 358 ssock = __mptcp_nmpc_socket(msk); 359 if (!ssock) { 360 release_sock(sk); 361 return -EINVAL; 362 } 363 364 ret = tcp_setsockopt(ssock->sk, SOL_IPV6, optname, optval, optlen); 365 if (ret == 0) 366 sk->sk_ipv6only = ssock->sk->sk_ipv6only; 367 368 release_sock(sk); 369 break; 370 } 371 372 return ret; 373 } 374 375 static bool mptcp_supported_sockopt(int level, int optname) 376 { 377 if (level == SOL_IP) { 378 switch (optname) { 379 /* should work fine */ 380 case IP_FREEBIND: 381 case IP_TRANSPARENT: 382 383 /* the following are control cmsg related */ 384 case IP_PKTINFO: 385 case IP_RECVTTL: 386 case IP_RECVTOS: 387 case IP_RECVOPTS: 388 case IP_RETOPTS: 389 case IP_PASSSEC: 390 case IP_RECVORIGDSTADDR: 391 case IP_CHECKSUM: 392 case IP_RECVFRAGSIZE: 393 394 /* common stuff that need some love */ 395 case IP_TOS: 396 case IP_TTL: 397 case IP_BIND_ADDRESS_NO_PORT: 398 case IP_MTU_DISCOVER: 399 case IP_RECVERR: 400 401 /* possibly less common may deserve some love */ 402 case IP_MINTTL: 403 404 /* the following is apparently a no-op for plain TCP */ 405 case IP_RECVERR_RFC4884: 406 return true; 407 } 408 409 /* IP_OPTIONS is not supported, needs subflow care */ 410 /* IP_HDRINCL, IP_NODEFRAG are not supported, RAW specific */ 411 /* IP_MULTICAST_TTL, IP_MULTICAST_LOOP, IP_UNICAST_IF, 412 * IP_ADD_MEMBERSHIP, IP_ADD_SOURCE_MEMBERSHIP, IP_DROP_MEMBERSHIP, 413 * IP_DROP_SOURCE_MEMBERSHIP, IP_BLOCK_SOURCE, IP_UNBLOCK_SOURCE, 414 * MCAST_JOIN_GROUP, MCAST_LEAVE_GROUP MCAST_JOIN_SOURCE_GROUP, 415 * MCAST_LEAVE_SOURCE_GROUP, MCAST_BLOCK_SOURCE, MCAST_UNBLOCK_SOURCE, 416 * MCAST_MSFILTER, IP_MULTICAST_ALL are not supported, better not deal 417 * with mcast stuff 418 */ 419 /* IP_IPSEC_POLICY, IP_XFRM_POLICY are nut supported, unrelated here */ 420 return false; 421 } 422 if (level == SOL_IPV6) { 423 switch (optname) { 424 case IPV6_V6ONLY: 425 426 /* the following are control cmsg related */ 427 case IPV6_RECVPKTINFO: 428 case IPV6_2292PKTINFO: 429 case IPV6_RECVHOPLIMIT: 430 case IPV6_2292HOPLIMIT: 431 case IPV6_RECVRTHDR: 432 case IPV6_2292RTHDR: 433 case IPV6_RECVHOPOPTS: 434 case IPV6_2292HOPOPTS: 435 case IPV6_RECVDSTOPTS: 436 case IPV6_2292DSTOPTS: 437 case IPV6_RECVTCLASS: 438 case IPV6_FLOWINFO: 439 case IPV6_RECVPATHMTU: 440 case IPV6_RECVORIGDSTADDR: 441 case IPV6_RECVFRAGSIZE: 442 443 /* the following ones need some love but are quite common */ 444 case IPV6_TCLASS: 445 case IPV6_TRANSPARENT: 446 case IPV6_FREEBIND: 447 case IPV6_PKTINFO: 448 case IPV6_2292PKTOPTIONS: 449 case IPV6_UNICAST_HOPS: 450 case IPV6_MTU_DISCOVER: 451 case IPV6_MTU: 452 case IPV6_RECVERR: 453 case IPV6_FLOWINFO_SEND: 454 case IPV6_FLOWLABEL_MGR: 455 case IPV6_MINHOPCOUNT: 456 case IPV6_DONTFRAG: 457 case IPV6_AUTOFLOWLABEL: 458 459 /* the following one is a no-op for plain TCP */ 460 case IPV6_RECVERR_RFC4884: 461 return true; 462 } 463 464 /* IPV6_HOPOPTS, IPV6_RTHDRDSTOPTS, IPV6_RTHDR, IPV6_DSTOPTS are 465 * not supported 466 */ 467 /* IPV6_MULTICAST_HOPS, IPV6_MULTICAST_LOOP, IPV6_UNICAST_IF, 468 * IPV6_MULTICAST_IF, IPV6_ADDRFORM, 469 * IPV6_ADD_MEMBERSHIP, IPV6_DROP_MEMBERSHIP, IPV6_JOIN_ANYCAST, 470 * IPV6_LEAVE_ANYCAST, IPV6_MULTICAST_ALL, MCAST_JOIN_GROUP, MCAST_LEAVE_GROUP, 471 * MCAST_JOIN_SOURCE_GROUP, MCAST_LEAVE_SOURCE_GROUP, 472 * MCAST_BLOCK_SOURCE, MCAST_UNBLOCK_SOURCE, MCAST_MSFILTER 473 * are not supported better not deal with mcast 474 */ 475 /* IPV6_ROUTER_ALERT, IPV6_ROUTER_ALERT_ISOLATE are not supported, since are evil */ 476 477 /* IPV6_IPSEC_POLICY, IPV6_XFRM_POLICY are not supported */ 478 /* IPV6_ADDR_PREFERENCES is not supported, we must be careful with subflows */ 479 return false; 480 } 481 if (level == SOL_TCP) { 482 switch (optname) { 483 /* the following are no-op or should work just fine */ 484 case TCP_THIN_DUPACK: 485 case TCP_DEFER_ACCEPT: 486 487 /* the following need some love */ 488 case TCP_MAXSEG: 489 case TCP_NODELAY: 490 case TCP_THIN_LINEAR_TIMEOUTS: 491 case TCP_CONGESTION: 492 case TCP_ULP: 493 case TCP_CORK: 494 case TCP_KEEPIDLE: 495 case TCP_KEEPINTVL: 496 case TCP_KEEPCNT: 497 case TCP_SYNCNT: 498 case TCP_SAVE_SYN: 499 case TCP_LINGER2: 500 case TCP_WINDOW_CLAMP: 501 case TCP_QUICKACK: 502 case TCP_USER_TIMEOUT: 503 case TCP_TIMESTAMP: 504 case TCP_NOTSENT_LOWAT: 505 case TCP_TX_DELAY: 506 return true; 507 } 508 509 /* TCP_MD5SIG, TCP_MD5SIG_EXT are not supported, MD5 is not compatible with MPTCP */ 510 511 /* TCP_REPAIR, TCP_REPAIR_QUEUE, TCP_QUEUE_SEQ, TCP_REPAIR_OPTIONS, 512 * TCP_REPAIR_WINDOW are not supported, better avoid this mess 513 */ 514 /* TCP_FASTOPEN_KEY, TCP_FASTOPEN TCP_FASTOPEN_CONNECT, TCP_FASTOPEN_NO_COOKIE, 515 * are not supported fastopen is currently unsupported 516 */ 517 /* TCP_INQ is currently unsupported, needs some recvmsg work */ 518 } 519 return false; 520 } 521 522 static int mptcp_setsockopt_sol_tcp_congestion(struct mptcp_sock *msk, sockptr_t optval, 523 unsigned int optlen) 524 { 525 struct mptcp_subflow_context *subflow; 526 struct sock *sk = (struct sock *)msk; 527 char name[TCP_CA_NAME_MAX]; 528 bool cap_net_admin; 529 int ret; 530 531 if (optlen < 1) 532 return -EINVAL; 533 534 ret = strncpy_from_sockptr(name, optval, 535 min_t(long, TCP_CA_NAME_MAX - 1, optlen)); 536 if (ret < 0) 537 return -EFAULT; 538 539 name[ret] = 0; 540 541 cap_net_admin = ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN); 542 543 ret = 0; 544 lock_sock(sk); 545 sockopt_seq_inc(msk); 546 mptcp_for_each_subflow(msk, subflow) { 547 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 548 int err; 549 550 lock_sock(ssk); 551 err = tcp_set_congestion_control(ssk, name, true, cap_net_admin); 552 if (err < 0 && ret == 0) 553 ret = err; 554 subflow->setsockopt_seq = msk->setsockopt_seq; 555 release_sock(ssk); 556 } 557 558 if (ret == 0) 559 strcpy(msk->ca_name, name); 560 561 release_sock(sk); 562 return ret; 563 } 564 565 static int mptcp_setsockopt_sol_tcp(struct mptcp_sock *msk, int optname, 566 sockptr_t optval, unsigned int optlen) 567 { 568 switch (optname) { 569 case TCP_ULP: 570 return -EOPNOTSUPP; 571 case TCP_CONGESTION: 572 return mptcp_setsockopt_sol_tcp_congestion(msk, optval, optlen); 573 } 574 575 return -EOPNOTSUPP; 576 } 577 578 int mptcp_setsockopt(struct sock *sk, int level, int optname, 579 sockptr_t optval, unsigned int optlen) 580 { 581 struct mptcp_sock *msk = mptcp_sk(sk); 582 struct sock *ssk; 583 584 pr_debug("msk=%p", msk); 585 586 if (level == SOL_SOCKET) 587 return mptcp_setsockopt_sol_socket(msk, optname, optval, optlen); 588 589 if (!mptcp_supported_sockopt(level, optname)) 590 return -ENOPROTOOPT; 591 592 /* @@ the meaning of setsockopt() when the socket is connected and 593 * there are multiple subflows is not yet defined. It is up to the 594 * MPTCP-level socket to configure the subflows until the subflow 595 * is in TCP fallback, when TCP socket options are passed through 596 * to the one remaining subflow. 597 */ 598 lock_sock(sk); 599 ssk = __mptcp_tcp_fallback(msk); 600 release_sock(sk); 601 if (ssk) 602 return tcp_setsockopt(ssk, level, optname, optval, optlen); 603 604 if (level == SOL_IPV6) 605 return mptcp_setsockopt_v6(msk, optname, optval, optlen); 606 607 if (level == SOL_TCP) 608 return mptcp_setsockopt_sol_tcp(msk, optname, optval, optlen); 609 610 return -EOPNOTSUPP; 611 } 612 613 static int mptcp_getsockopt_first_sf_only(struct mptcp_sock *msk, int level, int optname, 614 char __user *optval, int __user *optlen) 615 { 616 struct sock *sk = (struct sock *)msk; 617 struct socket *ssock; 618 int ret = -EINVAL; 619 struct sock *ssk; 620 621 lock_sock(sk); 622 ssk = msk->first; 623 if (ssk) { 624 ret = tcp_getsockopt(ssk, level, optname, optval, optlen); 625 goto out; 626 } 627 628 ssock = __mptcp_nmpc_socket(msk); 629 if (!ssock) 630 goto out; 631 632 ret = tcp_getsockopt(ssock->sk, level, optname, optval, optlen); 633 634 out: 635 release_sock(sk); 636 return ret; 637 } 638 639 static int mptcp_getsockopt_sol_tcp(struct mptcp_sock *msk, int optname, 640 char __user *optval, int __user *optlen) 641 { 642 switch (optname) { 643 case TCP_ULP: 644 case TCP_CONGESTION: 645 case TCP_INFO: 646 case TCP_CC_INFO: 647 return mptcp_getsockopt_first_sf_only(msk, SOL_TCP, optname, 648 optval, optlen); 649 } 650 return -EOPNOTSUPP; 651 } 652 653 int mptcp_getsockopt(struct sock *sk, int level, int optname, 654 char __user *optval, int __user *option) 655 { 656 struct mptcp_sock *msk = mptcp_sk(sk); 657 struct sock *ssk; 658 659 pr_debug("msk=%p", msk); 660 661 /* @@ the meaning of setsockopt() when the socket is connected and 662 * there are multiple subflows is not yet defined. It is up to the 663 * MPTCP-level socket to configure the subflows until the subflow 664 * is in TCP fallback, when socket options are passed through 665 * to the one remaining subflow. 666 */ 667 lock_sock(sk); 668 ssk = __mptcp_tcp_fallback(msk); 669 release_sock(sk); 670 if (ssk) 671 return tcp_getsockopt(ssk, level, optname, optval, option); 672 673 if (level == SOL_TCP) 674 return mptcp_getsockopt_sol_tcp(msk, optname, optval, option); 675 return -EOPNOTSUPP; 676 } 677 678 static void sync_socket_options(struct mptcp_sock *msk, struct sock *ssk) 679 { 680 static const unsigned int tx_rx_locks = SOCK_RCVBUF_LOCK | SOCK_SNDBUF_LOCK; 681 struct sock *sk = (struct sock *)msk; 682 683 if (ssk->sk_prot->keepalive) { 684 if (sock_flag(sk, SOCK_KEEPOPEN)) 685 ssk->sk_prot->keepalive(ssk, 1); 686 else 687 ssk->sk_prot->keepalive(ssk, 0); 688 } 689 690 ssk->sk_priority = sk->sk_priority; 691 ssk->sk_bound_dev_if = sk->sk_bound_dev_if; 692 ssk->sk_incoming_cpu = sk->sk_incoming_cpu; 693 694 if (sk->sk_userlocks & tx_rx_locks) { 695 ssk->sk_userlocks |= sk->sk_userlocks & tx_rx_locks; 696 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) 697 WRITE_ONCE(ssk->sk_sndbuf, sk->sk_sndbuf); 698 if (sk->sk_userlocks & SOCK_RCVBUF_LOCK) 699 WRITE_ONCE(ssk->sk_rcvbuf, sk->sk_rcvbuf); 700 } 701 702 if (sock_flag(sk, SOCK_LINGER)) { 703 ssk->sk_lingertime = sk->sk_lingertime; 704 sock_set_flag(ssk, SOCK_LINGER); 705 } else { 706 sock_reset_flag(ssk, SOCK_LINGER); 707 } 708 709 if (sk->sk_mark != ssk->sk_mark) { 710 ssk->sk_mark = sk->sk_mark; 711 sk_dst_reset(ssk); 712 } 713 714 sock_valbool_flag(ssk, SOCK_DBG, sock_flag(sk, SOCK_DBG)); 715 716 if (inet_csk(sk)->icsk_ca_ops != inet_csk(ssk)->icsk_ca_ops) 717 tcp_set_congestion_control(ssk, msk->ca_name, false, true); 718 } 719 720 static void __mptcp_sockopt_sync(struct mptcp_sock *msk, struct sock *ssk) 721 { 722 bool slow = lock_sock_fast(ssk); 723 724 sync_socket_options(msk, ssk); 725 726 unlock_sock_fast(ssk, slow); 727 } 728 729 void mptcp_sockopt_sync(struct mptcp_sock *msk, struct sock *ssk) 730 { 731 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 732 733 msk_owned_by_me(msk); 734 735 if (READ_ONCE(subflow->setsockopt_seq) != msk->setsockopt_seq) { 736 __mptcp_sockopt_sync(msk, ssk); 737 738 subflow->setsockopt_seq = msk->setsockopt_seq; 739 } 740 } 741 742 void mptcp_sockopt_sync_all(struct mptcp_sock *msk) 743 { 744 struct mptcp_subflow_context *subflow; 745 struct sock *sk = (struct sock *)msk; 746 u32 seq; 747 748 seq = sockopt_seq_reset(sk); 749 750 mptcp_for_each_subflow(msk, subflow) { 751 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 752 u32 sseq = READ_ONCE(subflow->setsockopt_seq); 753 754 if (sseq != msk->setsockopt_seq) { 755 __mptcp_sockopt_sync(msk, ssk); 756 WRITE_ONCE(subflow->setsockopt_seq, seq); 757 } else if (sseq != seq) { 758 WRITE_ONCE(subflow->setsockopt_seq, seq); 759 } 760 761 cond_resched(); 762 } 763 764 msk->setsockopt_seq = seq; 765 } 766