1 // SPDX-License-Identifier: GPL-2.0 2 /* Multipath TCP 3 * 4 * Copyright (c) 2020, Red Hat, Inc. 5 */ 6 7 #define pr_fmt(fmt) "MPTCP: " fmt 8 9 #include <linux/inet.h> 10 #include <linux/kernel.h> 11 #include <net/tcp.h> 12 #include <net/netns/generic.h> 13 #include <net/mptcp.h> 14 #include <net/genetlink.h> 15 #include <uapi/linux/mptcp.h> 16 17 #include "protocol.h" 18 #include "mib.h" 19 20 /* forward declaration */ 21 static struct genl_family mptcp_genl_family; 22 23 static int pm_nl_pernet_id; 24 25 struct mptcp_pm_addr_entry { 26 struct list_head list; 27 struct mptcp_addr_info addr; 28 u8 flags; 29 int ifindex; 30 struct socket *lsk; 31 }; 32 33 struct mptcp_pm_add_entry { 34 struct list_head list; 35 struct mptcp_addr_info addr; 36 struct timer_list add_timer; 37 struct mptcp_sock *sock; 38 u8 retrans_times; 39 }; 40 41 #define MAX_ADDR_ID 255 42 #define BITMAP_SZ DIV_ROUND_UP(MAX_ADDR_ID + 1, BITS_PER_LONG) 43 44 struct pm_nl_pernet { 45 /* protects pernet updates */ 46 spinlock_t lock; 47 struct list_head local_addr_list; 48 unsigned int addrs; 49 unsigned int stale_loss_cnt; 50 unsigned int add_addr_signal_max; 51 unsigned int add_addr_accept_max; 52 unsigned int local_addr_max; 53 unsigned int subflows_max; 54 unsigned int next_id; 55 unsigned long id_bitmap[BITMAP_SZ]; 56 }; 57 58 #define MPTCP_PM_ADDR_MAX 8 59 #define ADD_ADDR_RETRANS_MAX 3 60 61 static bool addresses_equal(const struct mptcp_addr_info *a, 62 struct mptcp_addr_info *b, bool use_port) 63 { 64 bool addr_equals = false; 65 66 if (a->family == b->family) { 67 if (a->family == AF_INET) 68 addr_equals = a->addr.s_addr == b->addr.s_addr; 69 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 70 else 71 addr_equals = !ipv6_addr_cmp(&a->addr6, &b->addr6); 72 } else if (a->family == AF_INET) { 73 if (ipv6_addr_v4mapped(&b->addr6)) 74 addr_equals = a->addr.s_addr == b->addr6.s6_addr32[3]; 75 } else if (b->family == AF_INET) { 76 if (ipv6_addr_v4mapped(&a->addr6)) 77 addr_equals = a->addr6.s6_addr32[3] == b->addr.s_addr; 78 #endif 79 } 80 81 if (!addr_equals) 82 return false; 83 if (!use_port) 84 return true; 85 86 return a->port == b->port; 87 } 88 89 static bool address_zero(const struct mptcp_addr_info *addr) 90 { 91 struct mptcp_addr_info zero; 92 93 memset(&zero, 0, sizeof(zero)); 94 zero.family = addr->family; 95 96 return addresses_equal(addr, &zero, true); 97 } 98 99 static void local_address(const struct sock_common *skc, 100 struct mptcp_addr_info *addr) 101 { 102 addr->family = skc->skc_family; 103 addr->port = htons(skc->skc_num); 104 if (addr->family == AF_INET) 105 addr->addr.s_addr = skc->skc_rcv_saddr; 106 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 107 else if (addr->family == AF_INET6) 108 addr->addr6 = skc->skc_v6_rcv_saddr; 109 #endif 110 } 111 112 static void remote_address(const struct sock_common *skc, 113 struct mptcp_addr_info *addr) 114 { 115 addr->family = skc->skc_family; 116 addr->port = skc->skc_dport; 117 if (addr->family == AF_INET) 118 addr->addr.s_addr = skc->skc_daddr; 119 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 120 else if (addr->family == AF_INET6) 121 addr->addr6 = skc->skc_v6_daddr; 122 #endif 123 } 124 125 static bool lookup_subflow_by_saddr(const struct list_head *list, 126 struct mptcp_addr_info *saddr) 127 { 128 struct mptcp_subflow_context *subflow; 129 struct mptcp_addr_info cur; 130 struct sock_common *skc; 131 132 list_for_each_entry(subflow, list, node) { 133 skc = (struct sock_common *)mptcp_subflow_tcp_sock(subflow); 134 135 local_address(skc, &cur); 136 if (addresses_equal(&cur, saddr, saddr->port)) 137 return true; 138 } 139 140 return false; 141 } 142 143 static bool lookup_subflow_by_daddr(const struct list_head *list, 144 struct mptcp_addr_info *daddr) 145 { 146 struct mptcp_subflow_context *subflow; 147 struct mptcp_addr_info cur; 148 struct sock_common *skc; 149 150 list_for_each_entry(subflow, list, node) { 151 skc = (struct sock_common *)mptcp_subflow_tcp_sock(subflow); 152 153 remote_address(skc, &cur); 154 if (addresses_equal(&cur, daddr, daddr->port)) 155 return true; 156 } 157 158 return false; 159 } 160 161 static struct mptcp_pm_addr_entry * 162 select_local_address(const struct pm_nl_pernet *pernet, 163 struct mptcp_sock *msk) 164 { 165 struct mptcp_pm_addr_entry *entry, *ret = NULL; 166 struct sock *sk = (struct sock *)msk; 167 168 msk_owned_by_me(msk); 169 170 rcu_read_lock(); 171 __mptcp_flush_join_list(msk); 172 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 173 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW)) 174 continue; 175 176 if (entry->addr.family != sk->sk_family) { 177 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 178 if ((entry->addr.family == AF_INET && 179 !ipv6_addr_v4mapped(&sk->sk_v6_daddr)) || 180 (sk->sk_family == AF_INET && 181 !ipv6_addr_v4mapped(&entry->addr.addr6))) 182 #endif 183 continue; 184 } 185 186 /* avoid any address already in use by subflows and 187 * pending join 188 */ 189 if (!lookup_subflow_by_saddr(&msk->conn_list, &entry->addr)) { 190 ret = entry; 191 break; 192 } 193 } 194 rcu_read_unlock(); 195 return ret; 196 } 197 198 static struct mptcp_pm_addr_entry * 199 select_signal_address(struct pm_nl_pernet *pernet, unsigned int pos) 200 { 201 struct mptcp_pm_addr_entry *entry, *ret = NULL; 202 int i = 0; 203 204 rcu_read_lock(); 205 /* do not keep any additional per socket state, just signal 206 * the address list in order. 207 * Note: removal from the local address list during the msk life-cycle 208 * can lead to additional addresses not being announced. 209 */ 210 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 211 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) 212 continue; 213 if (i++ == pos) { 214 ret = entry; 215 break; 216 } 217 } 218 rcu_read_unlock(); 219 return ret; 220 } 221 222 unsigned int mptcp_pm_get_add_addr_signal_max(struct mptcp_sock *msk) 223 { 224 struct pm_nl_pernet *pernet; 225 226 pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id); 227 return READ_ONCE(pernet->add_addr_signal_max); 228 } 229 EXPORT_SYMBOL_GPL(mptcp_pm_get_add_addr_signal_max); 230 231 unsigned int mptcp_pm_get_add_addr_accept_max(struct mptcp_sock *msk) 232 { 233 struct pm_nl_pernet *pernet; 234 235 pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id); 236 return READ_ONCE(pernet->add_addr_accept_max); 237 } 238 EXPORT_SYMBOL_GPL(mptcp_pm_get_add_addr_accept_max); 239 240 unsigned int mptcp_pm_get_subflows_max(struct mptcp_sock *msk) 241 { 242 struct pm_nl_pernet *pernet; 243 244 pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id); 245 return READ_ONCE(pernet->subflows_max); 246 } 247 EXPORT_SYMBOL_GPL(mptcp_pm_get_subflows_max); 248 249 unsigned int mptcp_pm_get_local_addr_max(struct mptcp_sock *msk) 250 { 251 struct pm_nl_pernet *pernet; 252 253 pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id); 254 return READ_ONCE(pernet->local_addr_max); 255 } 256 EXPORT_SYMBOL_GPL(mptcp_pm_get_local_addr_max); 257 258 static void check_work_pending(struct mptcp_sock *msk) 259 { 260 if (msk->pm.add_addr_signaled == mptcp_pm_get_add_addr_signal_max(msk) && 261 (msk->pm.local_addr_used == mptcp_pm_get_local_addr_max(msk) || 262 msk->pm.subflows == mptcp_pm_get_subflows_max(msk))) 263 WRITE_ONCE(msk->pm.work_pending, false); 264 } 265 266 struct mptcp_pm_add_entry * 267 mptcp_lookup_anno_list_by_saddr(struct mptcp_sock *msk, 268 struct mptcp_addr_info *addr) 269 { 270 struct mptcp_pm_add_entry *entry; 271 272 lockdep_assert_held(&msk->pm.lock); 273 274 list_for_each_entry(entry, &msk->pm.anno_list, list) { 275 if (addresses_equal(&entry->addr, addr, true)) 276 return entry; 277 } 278 279 return NULL; 280 } 281 282 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk) 283 { 284 struct mptcp_pm_add_entry *entry; 285 struct mptcp_addr_info saddr; 286 bool ret = false; 287 288 local_address((struct sock_common *)sk, &saddr); 289 290 spin_lock_bh(&msk->pm.lock); 291 list_for_each_entry(entry, &msk->pm.anno_list, list) { 292 if (addresses_equal(&entry->addr, &saddr, true)) { 293 ret = true; 294 goto out; 295 } 296 } 297 298 out: 299 spin_unlock_bh(&msk->pm.lock); 300 return ret; 301 } 302 303 static void mptcp_pm_add_timer(struct timer_list *timer) 304 { 305 struct mptcp_pm_add_entry *entry = from_timer(entry, timer, add_timer); 306 struct mptcp_sock *msk = entry->sock; 307 struct sock *sk = (struct sock *)msk; 308 309 pr_debug("msk=%p", msk); 310 311 if (!msk) 312 return; 313 314 if (inet_sk_state_load(sk) == TCP_CLOSE) 315 return; 316 317 if (!entry->addr.id) 318 return; 319 320 if (mptcp_pm_should_add_signal_addr(msk)) { 321 sk_reset_timer(sk, timer, jiffies + TCP_RTO_MAX / 8); 322 goto out; 323 } 324 325 spin_lock_bh(&msk->pm.lock); 326 327 if (!mptcp_pm_should_add_signal_addr(msk)) { 328 pr_debug("retransmit ADD_ADDR id=%d", entry->addr.id); 329 mptcp_pm_announce_addr(msk, &entry->addr, false); 330 mptcp_pm_add_addr_send_ack(msk); 331 entry->retrans_times++; 332 } 333 334 if (entry->retrans_times < ADD_ADDR_RETRANS_MAX) 335 sk_reset_timer(sk, timer, 336 jiffies + mptcp_get_add_addr_timeout(sock_net(sk))); 337 338 spin_unlock_bh(&msk->pm.lock); 339 340 if (entry->retrans_times == ADD_ADDR_RETRANS_MAX) 341 mptcp_pm_subflow_established(msk); 342 343 out: 344 __sock_put(sk); 345 } 346 347 struct mptcp_pm_add_entry * 348 mptcp_pm_del_add_timer(struct mptcp_sock *msk, 349 struct mptcp_addr_info *addr, bool check_id) 350 { 351 struct mptcp_pm_add_entry *entry; 352 struct sock *sk = (struct sock *)msk; 353 354 spin_lock_bh(&msk->pm.lock); 355 entry = mptcp_lookup_anno_list_by_saddr(msk, addr); 356 if (entry && (!check_id || entry->addr.id == addr->id)) 357 entry->retrans_times = ADD_ADDR_RETRANS_MAX; 358 spin_unlock_bh(&msk->pm.lock); 359 360 if (entry && (!check_id || entry->addr.id == addr->id)) 361 sk_stop_timer_sync(sk, &entry->add_timer); 362 363 return entry; 364 } 365 366 static bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk, 367 struct mptcp_pm_addr_entry *entry) 368 { 369 struct mptcp_pm_add_entry *add_entry = NULL; 370 struct sock *sk = (struct sock *)msk; 371 struct net *net = sock_net(sk); 372 373 lockdep_assert_held(&msk->pm.lock); 374 375 if (mptcp_lookup_anno_list_by_saddr(msk, &entry->addr)) 376 return false; 377 378 add_entry = kmalloc(sizeof(*add_entry), GFP_ATOMIC); 379 if (!add_entry) 380 return false; 381 382 list_add(&add_entry->list, &msk->pm.anno_list); 383 384 add_entry->addr = entry->addr; 385 add_entry->sock = msk; 386 add_entry->retrans_times = 0; 387 388 timer_setup(&add_entry->add_timer, mptcp_pm_add_timer, 0); 389 sk_reset_timer(sk, &add_entry->add_timer, 390 jiffies + mptcp_get_add_addr_timeout(net)); 391 392 return true; 393 } 394 395 void mptcp_pm_free_anno_list(struct mptcp_sock *msk) 396 { 397 struct mptcp_pm_add_entry *entry, *tmp; 398 struct sock *sk = (struct sock *)msk; 399 LIST_HEAD(free_list); 400 401 pr_debug("msk=%p", msk); 402 403 spin_lock_bh(&msk->pm.lock); 404 list_splice_init(&msk->pm.anno_list, &free_list); 405 spin_unlock_bh(&msk->pm.lock); 406 407 list_for_each_entry_safe(entry, tmp, &free_list, list) { 408 sk_stop_timer_sync(sk, &entry->add_timer); 409 kfree(entry); 410 } 411 } 412 413 static bool lookup_address_in_vec(struct mptcp_addr_info *addrs, unsigned int nr, 414 struct mptcp_addr_info *addr) 415 { 416 int i; 417 418 for (i = 0; i < nr; i++) { 419 if (addresses_equal(&addrs[i], addr, addr->port)) 420 return true; 421 } 422 423 return false; 424 } 425 426 /* Fill all the remote addresses into the array addrs[], 427 * and return the array size. 428 */ 429 static unsigned int fill_remote_addresses_vec(struct mptcp_sock *msk, bool fullmesh, 430 struct mptcp_addr_info *addrs) 431 { 432 struct sock *sk = (struct sock *)msk, *ssk; 433 struct mptcp_subflow_context *subflow; 434 struct mptcp_addr_info remote = { 0 }; 435 unsigned int subflows_max; 436 int i = 0; 437 438 subflows_max = mptcp_pm_get_subflows_max(msk); 439 440 /* Non-fullmesh endpoint, fill in the single entry 441 * corresponding to the primary MPC subflow remote address 442 */ 443 if (!fullmesh) { 444 remote_address((struct sock_common *)sk, &remote); 445 msk->pm.subflows++; 446 addrs[i++] = remote; 447 } else { 448 mptcp_for_each_subflow(msk, subflow) { 449 ssk = mptcp_subflow_tcp_sock(subflow); 450 remote_address((struct sock_common *)ssk, &remote); 451 if (!lookup_address_in_vec(addrs, i, &remote) && 452 msk->pm.subflows < subflows_max) { 453 msk->pm.subflows++; 454 addrs[i++] = remote; 455 } 456 } 457 } 458 459 return i; 460 } 461 462 static void mptcp_pm_create_subflow_or_signal_addr(struct mptcp_sock *msk) 463 { 464 struct sock *sk = (struct sock *)msk; 465 struct mptcp_pm_addr_entry *local; 466 unsigned int add_addr_signal_max; 467 unsigned int local_addr_max; 468 struct pm_nl_pernet *pernet; 469 unsigned int subflows_max; 470 471 pernet = net_generic(sock_net(sk), pm_nl_pernet_id); 472 473 add_addr_signal_max = mptcp_pm_get_add_addr_signal_max(msk); 474 local_addr_max = mptcp_pm_get_local_addr_max(msk); 475 subflows_max = mptcp_pm_get_subflows_max(msk); 476 477 pr_debug("local %d:%d signal %d:%d subflows %d:%d\n", 478 msk->pm.local_addr_used, local_addr_max, 479 msk->pm.add_addr_signaled, add_addr_signal_max, 480 msk->pm.subflows, subflows_max); 481 482 /* check first for announce */ 483 if (msk->pm.add_addr_signaled < add_addr_signal_max) { 484 local = select_signal_address(pernet, 485 msk->pm.add_addr_signaled); 486 487 if (local) { 488 if (mptcp_pm_alloc_anno_list(msk, local)) { 489 msk->pm.add_addr_signaled++; 490 mptcp_pm_announce_addr(msk, &local->addr, false); 491 mptcp_pm_nl_addr_send_ack(msk); 492 } 493 } else { 494 /* pick failed, avoid fourther attempts later */ 495 msk->pm.local_addr_used = add_addr_signal_max; 496 } 497 498 check_work_pending(msk); 499 } 500 501 /* check if should create a new subflow */ 502 if (msk->pm.local_addr_used < local_addr_max && 503 msk->pm.subflows < subflows_max && 504 !READ_ONCE(msk->pm.remote_deny_join_id0)) { 505 local = select_local_address(pernet, msk); 506 if (local) { 507 bool fullmesh = !!(local->flags & MPTCP_PM_ADDR_FLAG_FULLMESH); 508 struct mptcp_addr_info addrs[MPTCP_PM_ADDR_MAX]; 509 int i, nr; 510 511 msk->pm.local_addr_used++; 512 check_work_pending(msk); 513 nr = fill_remote_addresses_vec(msk, fullmesh, addrs); 514 spin_unlock_bh(&msk->pm.lock); 515 for (i = 0; i < nr; i++) 516 __mptcp_subflow_connect(sk, &local->addr, &addrs[i]); 517 spin_lock_bh(&msk->pm.lock); 518 return; 519 } 520 521 /* lookup failed, avoid fourther attempts later */ 522 msk->pm.local_addr_used = local_addr_max; 523 check_work_pending(msk); 524 } 525 } 526 527 static void mptcp_pm_nl_fully_established(struct mptcp_sock *msk) 528 { 529 mptcp_pm_create_subflow_or_signal_addr(msk); 530 } 531 532 static void mptcp_pm_nl_subflow_established(struct mptcp_sock *msk) 533 { 534 mptcp_pm_create_subflow_or_signal_addr(msk); 535 } 536 537 /* Fill all the local addresses into the array addrs[], 538 * and return the array size. 539 */ 540 static unsigned int fill_local_addresses_vec(struct mptcp_sock *msk, 541 struct mptcp_addr_info *addrs) 542 { 543 struct sock *sk = (struct sock *)msk; 544 struct mptcp_pm_addr_entry *entry; 545 struct mptcp_addr_info local; 546 struct pm_nl_pernet *pernet; 547 unsigned int subflows_max; 548 int i = 0; 549 550 pernet = net_generic(sock_net(sk), pm_nl_pernet_id); 551 subflows_max = mptcp_pm_get_subflows_max(msk); 552 553 rcu_read_lock(); 554 __mptcp_flush_join_list(msk); 555 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 556 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_FULLMESH)) 557 continue; 558 559 if (entry->addr.family != sk->sk_family) { 560 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 561 if ((entry->addr.family == AF_INET && 562 !ipv6_addr_v4mapped(&sk->sk_v6_daddr)) || 563 (sk->sk_family == AF_INET && 564 !ipv6_addr_v4mapped(&entry->addr.addr6))) 565 #endif 566 continue; 567 } 568 569 if (msk->pm.subflows < subflows_max) { 570 msk->pm.subflows++; 571 addrs[i++] = entry->addr; 572 } 573 } 574 rcu_read_unlock(); 575 576 /* If the array is empty, fill in the single 577 * 'IPADDRANY' local address 578 */ 579 if (!i) { 580 memset(&local, 0, sizeof(local)); 581 local.family = msk->pm.remote.family; 582 583 msk->pm.subflows++; 584 addrs[i++] = local; 585 } 586 587 return i; 588 } 589 590 static void mptcp_pm_nl_add_addr_received(struct mptcp_sock *msk) 591 { 592 struct mptcp_addr_info addrs[MPTCP_PM_ADDR_MAX]; 593 struct sock *sk = (struct sock *)msk; 594 unsigned int add_addr_accept_max; 595 struct mptcp_addr_info remote; 596 unsigned int subflows_max; 597 int i, nr; 598 599 add_addr_accept_max = mptcp_pm_get_add_addr_accept_max(msk); 600 subflows_max = mptcp_pm_get_subflows_max(msk); 601 602 pr_debug("accepted %d:%d remote family %d", 603 msk->pm.add_addr_accepted, add_addr_accept_max, 604 msk->pm.remote.family); 605 606 if (lookup_subflow_by_daddr(&msk->conn_list, &msk->pm.remote)) 607 goto add_addr_echo; 608 609 /* connect to the specified remote address, using whatever 610 * local address the routing configuration will pick. 611 */ 612 remote = msk->pm.remote; 613 if (!remote.port) 614 remote.port = sk->sk_dport; 615 nr = fill_local_addresses_vec(msk, addrs); 616 617 msk->pm.add_addr_accepted++; 618 if (msk->pm.add_addr_accepted >= add_addr_accept_max || 619 msk->pm.subflows >= subflows_max) 620 WRITE_ONCE(msk->pm.accept_addr, false); 621 622 spin_unlock_bh(&msk->pm.lock); 623 for (i = 0; i < nr; i++) 624 __mptcp_subflow_connect(sk, &addrs[i], &remote); 625 spin_lock_bh(&msk->pm.lock); 626 627 add_addr_echo: 628 mptcp_pm_announce_addr(msk, &msk->pm.remote, true); 629 mptcp_pm_nl_addr_send_ack(msk); 630 } 631 632 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk) 633 { 634 struct mptcp_subflow_context *subflow; 635 636 msk_owned_by_me(msk); 637 lockdep_assert_held(&msk->pm.lock); 638 639 if (!mptcp_pm_should_add_signal(msk) && 640 !mptcp_pm_should_rm_signal(msk)) 641 return; 642 643 __mptcp_flush_join_list(msk); 644 subflow = list_first_entry_or_null(&msk->conn_list, typeof(*subflow), node); 645 if (subflow) { 646 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 647 648 spin_unlock_bh(&msk->pm.lock); 649 pr_debug("send ack for %s", 650 mptcp_pm_should_add_signal(msk) ? "add_addr" : "rm_addr"); 651 652 mptcp_subflow_send_ack(ssk); 653 spin_lock_bh(&msk->pm.lock); 654 } 655 } 656 657 int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk, 658 struct mptcp_addr_info *addr, 659 u8 bkup) 660 { 661 struct mptcp_subflow_context *subflow; 662 663 pr_debug("bkup=%d", bkup); 664 665 mptcp_for_each_subflow(msk, subflow) { 666 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 667 struct sock *sk = (struct sock *)msk; 668 struct mptcp_addr_info local; 669 670 local_address((struct sock_common *)ssk, &local); 671 if (!addresses_equal(&local, addr, addr->port)) 672 continue; 673 674 subflow->backup = bkup; 675 subflow->send_mp_prio = 1; 676 subflow->request_bkup = bkup; 677 __MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_MPPRIOTX); 678 679 spin_unlock_bh(&msk->pm.lock); 680 pr_debug("send ack for mp_prio"); 681 mptcp_subflow_send_ack(ssk); 682 spin_lock_bh(&msk->pm.lock); 683 684 return 0; 685 } 686 687 return -EINVAL; 688 } 689 690 static void mptcp_pm_nl_rm_addr_or_subflow(struct mptcp_sock *msk, 691 const struct mptcp_rm_list *rm_list, 692 enum linux_mptcp_mib_field rm_type) 693 { 694 struct mptcp_subflow_context *subflow, *tmp; 695 struct sock *sk = (struct sock *)msk; 696 u8 i; 697 698 pr_debug("%s rm_list_nr %d", 699 rm_type == MPTCP_MIB_RMADDR ? "address" : "subflow", rm_list->nr); 700 701 msk_owned_by_me(msk); 702 703 if (!rm_list->nr) 704 return; 705 706 if (list_empty(&msk->conn_list)) 707 return; 708 709 for (i = 0; i < rm_list->nr; i++) { 710 list_for_each_entry_safe(subflow, tmp, &msk->conn_list, node) { 711 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 712 int how = RCV_SHUTDOWN | SEND_SHUTDOWN; 713 u8 id = subflow->local_id; 714 715 if (rm_type == MPTCP_MIB_RMADDR) 716 id = subflow->remote_id; 717 718 if (rm_list->ids[i] != id) 719 continue; 720 721 pr_debug(" -> %s rm_list_ids[%d]=%u local_id=%u remote_id=%u", 722 rm_type == MPTCP_MIB_RMADDR ? "address" : "subflow", 723 i, rm_list->ids[i], subflow->local_id, subflow->remote_id); 724 spin_unlock_bh(&msk->pm.lock); 725 mptcp_subflow_shutdown(sk, ssk, how); 726 mptcp_close_ssk(sk, ssk, subflow); 727 spin_lock_bh(&msk->pm.lock); 728 729 if (rm_type == MPTCP_MIB_RMADDR) { 730 msk->pm.add_addr_accepted--; 731 WRITE_ONCE(msk->pm.accept_addr, true); 732 } else if (rm_type == MPTCP_MIB_RMSUBFLOW) { 733 msk->pm.local_addr_used--; 734 } 735 msk->pm.subflows--; 736 __MPTCP_INC_STATS(sock_net(sk), rm_type); 737 } 738 } 739 } 740 741 static void mptcp_pm_nl_rm_addr_received(struct mptcp_sock *msk) 742 { 743 mptcp_pm_nl_rm_addr_or_subflow(msk, &msk->pm.rm_list_rx, MPTCP_MIB_RMADDR); 744 } 745 746 void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk, 747 const struct mptcp_rm_list *rm_list) 748 { 749 mptcp_pm_nl_rm_addr_or_subflow(msk, rm_list, MPTCP_MIB_RMSUBFLOW); 750 } 751 752 void mptcp_pm_nl_work(struct mptcp_sock *msk) 753 { 754 struct mptcp_pm_data *pm = &msk->pm; 755 756 msk_owned_by_me(msk); 757 758 spin_lock_bh(&msk->pm.lock); 759 760 pr_debug("msk=%p status=%x", msk, pm->status); 761 if (pm->status & BIT(MPTCP_PM_ADD_ADDR_RECEIVED)) { 762 pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_RECEIVED); 763 mptcp_pm_nl_add_addr_received(msk); 764 } 765 if (pm->status & BIT(MPTCP_PM_ADD_ADDR_SEND_ACK)) { 766 pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_SEND_ACK); 767 mptcp_pm_nl_addr_send_ack(msk); 768 } 769 if (pm->status & BIT(MPTCP_PM_RM_ADDR_RECEIVED)) { 770 pm->status &= ~BIT(MPTCP_PM_RM_ADDR_RECEIVED); 771 mptcp_pm_nl_rm_addr_received(msk); 772 } 773 if (pm->status & BIT(MPTCP_PM_ESTABLISHED)) { 774 pm->status &= ~BIT(MPTCP_PM_ESTABLISHED); 775 mptcp_pm_nl_fully_established(msk); 776 } 777 if (pm->status & BIT(MPTCP_PM_SUBFLOW_ESTABLISHED)) { 778 pm->status &= ~BIT(MPTCP_PM_SUBFLOW_ESTABLISHED); 779 mptcp_pm_nl_subflow_established(msk); 780 } 781 782 spin_unlock_bh(&msk->pm.lock); 783 } 784 785 static bool address_use_port(struct mptcp_pm_addr_entry *entry) 786 { 787 return (entry->flags & 788 (MPTCP_PM_ADDR_FLAG_SIGNAL | MPTCP_PM_ADDR_FLAG_SUBFLOW)) == 789 MPTCP_PM_ADDR_FLAG_SIGNAL; 790 } 791 792 static int mptcp_pm_nl_append_new_local_addr(struct pm_nl_pernet *pernet, 793 struct mptcp_pm_addr_entry *entry) 794 { 795 struct mptcp_pm_addr_entry *cur; 796 unsigned int addr_max; 797 int ret = -EINVAL; 798 799 spin_lock_bh(&pernet->lock); 800 /* to keep the code simple, don't do IDR-like allocation for address ID, 801 * just bail when we exceed limits 802 */ 803 if (pernet->next_id == MAX_ADDR_ID) 804 pernet->next_id = 1; 805 if (pernet->addrs >= MPTCP_PM_ADDR_MAX) 806 goto out; 807 if (test_bit(entry->addr.id, pernet->id_bitmap)) 808 goto out; 809 810 /* do not insert duplicate address, differentiate on port only 811 * singled addresses 812 */ 813 list_for_each_entry(cur, &pernet->local_addr_list, list) { 814 if (addresses_equal(&cur->addr, &entry->addr, 815 address_use_port(entry) && 816 address_use_port(cur))) 817 goto out; 818 } 819 820 if (!entry->addr.id) { 821 find_next: 822 entry->addr.id = find_next_zero_bit(pernet->id_bitmap, 823 MAX_ADDR_ID + 1, 824 pernet->next_id); 825 if ((!entry->addr.id || entry->addr.id > MAX_ADDR_ID) && 826 pernet->next_id != 1) { 827 pernet->next_id = 1; 828 goto find_next; 829 } 830 } 831 832 if (!entry->addr.id || entry->addr.id > MAX_ADDR_ID) 833 goto out; 834 835 __set_bit(entry->addr.id, pernet->id_bitmap); 836 if (entry->addr.id > pernet->next_id) 837 pernet->next_id = entry->addr.id; 838 839 if (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL) { 840 addr_max = pernet->add_addr_signal_max; 841 WRITE_ONCE(pernet->add_addr_signal_max, addr_max + 1); 842 } 843 if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) { 844 addr_max = pernet->local_addr_max; 845 WRITE_ONCE(pernet->local_addr_max, addr_max + 1); 846 } 847 848 pernet->addrs++; 849 list_add_tail_rcu(&entry->list, &pernet->local_addr_list); 850 ret = entry->addr.id; 851 852 out: 853 spin_unlock_bh(&pernet->lock); 854 return ret; 855 } 856 857 static int mptcp_pm_nl_create_listen_socket(struct sock *sk, 858 struct mptcp_pm_addr_entry *entry) 859 { 860 struct sockaddr_storage addr; 861 struct mptcp_sock *msk; 862 struct socket *ssock; 863 int backlog = 1024; 864 int err; 865 866 err = sock_create_kern(sock_net(sk), entry->addr.family, 867 SOCK_STREAM, IPPROTO_MPTCP, &entry->lsk); 868 if (err) 869 return err; 870 871 msk = mptcp_sk(entry->lsk->sk); 872 if (!msk) { 873 err = -EINVAL; 874 goto out; 875 } 876 877 ssock = __mptcp_nmpc_socket(msk); 878 if (!ssock) { 879 err = -EINVAL; 880 goto out; 881 } 882 883 mptcp_info2sockaddr(&entry->addr, &addr, entry->addr.family); 884 err = kernel_bind(ssock, (struct sockaddr *)&addr, 885 sizeof(struct sockaddr_in)); 886 if (err) { 887 pr_warn("kernel_bind error, err=%d", err); 888 goto out; 889 } 890 891 err = kernel_listen(ssock, backlog); 892 if (err) { 893 pr_warn("kernel_listen error, err=%d", err); 894 goto out; 895 } 896 897 return 0; 898 899 out: 900 sock_release(entry->lsk); 901 return err; 902 } 903 904 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct sock_common *skc) 905 { 906 struct mptcp_pm_addr_entry *entry; 907 struct mptcp_addr_info skc_local; 908 struct mptcp_addr_info msk_local; 909 struct pm_nl_pernet *pernet; 910 int ret = -1; 911 912 if (WARN_ON_ONCE(!msk)) 913 return -1; 914 915 /* The 0 ID mapping is defined by the first subflow, copied into the msk 916 * addr 917 */ 918 local_address((struct sock_common *)msk, &msk_local); 919 local_address((struct sock_common *)skc, &skc_local); 920 if (addresses_equal(&msk_local, &skc_local, false)) 921 return 0; 922 923 if (address_zero(&skc_local)) 924 return 0; 925 926 pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id); 927 928 rcu_read_lock(); 929 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 930 if (addresses_equal(&entry->addr, &skc_local, entry->addr.port)) { 931 ret = entry->addr.id; 932 break; 933 } 934 } 935 rcu_read_unlock(); 936 if (ret >= 0) 937 return ret; 938 939 /* address not found, add to local list */ 940 entry = kmalloc(sizeof(*entry), GFP_ATOMIC); 941 if (!entry) 942 return -ENOMEM; 943 944 entry->addr = skc_local; 945 entry->addr.id = 0; 946 entry->addr.port = 0; 947 entry->ifindex = 0; 948 entry->flags = 0; 949 entry->lsk = NULL; 950 ret = mptcp_pm_nl_append_new_local_addr(pernet, entry); 951 if (ret < 0) 952 kfree(entry); 953 954 return ret; 955 } 956 957 void mptcp_pm_nl_data_init(struct mptcp_sock *msk) 958 { 959 struct mptcp_pm_data *pm = &msk->pm; 960 bool subflows; 961 962 subflows = !!mptcp_pm_get_subflows_max(msk); 963 WRITE_ONCE(pm->work_pending, (!!mptcp_pm_get_local_addr_max(msk) && subflows) || 964 !!mptcp_pm_get_add_addr_signal_max(msk)); 965 WRITE_ONCE(pm->accept_addr, !!mptcp_pm_get_add_addr_accept_max(msk) && subflows); 966 WRITE_ONCE(pm->accept_subflow, subflows); 967 } 968 969 #define MPTCP_PM_CMD_GRP_OFFSET 0 970 #define MPTCP_PM_EV_GRP_OFFSET 1 971 972 static const struct genl_multicast_group mptcp_pm_mcgrps[] = { 973 [MPTCP_PM_CMD_GRP_OFFSET] = { .name = MPTCP_PM_CMD_GRP_NAME, }, 974 [MPTCP_PM_EV_GRP_OFFSET] = { .name = MPTCP_PM_EV_GRP_NAME, 975 .flags = GENL_UNS_ADMIN_PERM, 976 }, 977 }; 978 979 static const struct nla_policy 980 mptcp_pm_addr_policy[MPTCP_PM_ADDR_ATTR_MAX + 1] = { 981 [MPTCP_PM_ADDR_ATTR_FAMILY] = { .type = NLA_U16, }, 982 [MPTCP_PM_ADDR_ATTR_ID] = { .type = NLA_U8, }, 983 [MPTCP_PM_ADDR_ATTR_ADDR4] = { .type = NLA_U32, }, 984 [MPTCP_PM_ADDR_ATTR_ADDR6] = 985 NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)), 986 [MPTCP_PM_ADDR_ATTR_PORT] = { .type = NLA_U16 }, 987 [MPTCP_PM_ADDR_ATTR_FLAGS] = { .type = NLA_U32 }, 988 [MPTCP_PM_ADDR_ATTR_IF_IDX] = { .type = NLA_S32 }, 989 }; 990 991 static const struct nla_policy mptcp_pm_policy[MPTCP_PM_ATTR_MAX + 1] = { 992 [MPTCP_PM_ATTR_ADDR] = 993 NLA_POLICY_NESTED(mptcp_pm_addr_policy), 994 [MPTCP_PM_ATTR_RCV_ADD_ADDRS] = { .type = NLA_U32, }, 995 [MPTCP_PM_ATTR_SUBFLOWS] = { .type = NLA_U32, }, 996 }; 997 998 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk) 999 { 1000 struct mptcp_subflow_context *iter, *subflow = mptcp_subflow_ctx(ssk); 1001 struct sock *sk = (struct sock *)msk; 1002 unsigned int active_max_loss_cnt; 1003 struct net *net = sock_net(sk); 1004 unsigned int stale_loss_cnt; 1005 bool slow; 1006 1007 stale_loss_cnt = mptcp_stale_loss_cnt(net); 1008 if (subflow->stale || !stale_loss_cnt || subflow->stale_count <= stale_loss_cnt) 1009 return; 1010 1011 /* look for another available subflow not in loss state */ 1012 active_max_loss_cnt = max_t(int, stale_loss_cnt - 1, 1); 1013 mptcp_for_each_subflow(msk, iter) { 1014 if (iter != subflow && mptcp_subflow_active(iter) && 1015 iter->stale_count < active_max_loss_cnt) { 1016 /* we have some alternatives, try to mark this subflow as idle ...*/ 1017 slow = lock_sock_fast(ssk); 1018 if (!tcp_rtx_and_write_queues_empty(ssk)) { 1019 subflow->stale = 1; 1020 __mptcp_retransmit_pending_data(sk); 1021 MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_SUBFLOWSTALE); 1022 } 1023 unlock_sock_fast(ssk, slow); 1024 1025 /* always try to push the pending data regarless of re-injections: 1026 * we can possibly use backup subflows now, and subflow selection 1027 * is cheap under the msk socket lock 1028 */ 1029 __mptcp_push_pending(sk, 0); 1030 return; 1031 } 1032 } 1033 } 1034 1035 static int mptcp_pm_family_to_addr(int family) 1036 { 1037 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1038 if (family == AF_INET6) 1039 return MPTCP_PM_ADDR_ATTR_ADDR6; 1040 #endif 1041 return MPTCP_PM_ADDR_ATTR_ADDR4; 1042 } 1043 1044 static int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info, 1045 bool require_family, 1046 struct mptcp_pm_addr_entry *entry) 1047 { 1048 struct nlattr *tb[MPTCP_PM_ADDR_ATTR_MAX + 1]; 1049 int err, addr_addr; 1050 1051 if (!attr) { 1052 GENL_SET_ERR_MSG(info, "missing address info"); 1053 return -EINVAL; 1054 } 1055 1056 /* no validation needed - was already done via nested policy */ 1057 err = nla_parse_nested_deprecated(tb, MPTCP_PM_ADDR_ATTR_MAX, attr, 1058 mptcp_pm_addr_policy, info->extack); 1059 if (err) 1060 return err; 1061 1062 memset(entry, 0, sizeof(*entry)); 1063 if (!tb[MPTCP_PM_ADDR_ATTR_FAMILY]) { 1064 if (!require_family) 1065 goto skip_family; 1066 1067 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1068 "missing family"); 1069 return -EINVAL; 1070 } 1071 1072 entry->addr.family = nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_FAMILY]); 1073 if (entry->addr.family != AF_INET 1074 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1075 && entry->addr.family != AF_INET6 1076 #endif 1077 ) { 1078 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1079 "unknown address family"); 1080 return -EINVAL; 1081 } 1082 addr_addr = mptcp_pm_family_to_addr(entry->addr.family); 1083 if (!tb[addr_addr]) { 1084 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1085 "missing address data"); 1086 return -EINVAL; 1087 } 1088 1089 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1090 if (entry->addr.family == AF_INET6) 1091 entry->addr.addr6 = nla_get_in6_addr(tb[addr_addr]); 1092 else 1093 #endif 1094 entry->addr.addr.s_addr = nla_get_in_addr(tb[addr_addr]); 1095 1096 skip_family: 1097 if (tb[MPTCP_PM_ADDR_ATTR_IF_IDX]) { 1098 u32 val = nla_get_s32(tb[MPTCP_PM_ADDR_ATTR_IF_IDX]); 1099 1100 entry->ifindex = val; 1101 } 1102 1103 if (tb[MPTCP_PM_ADDR_ATTR_ID]) 1104 entry->addr.id = nla_get_u8(tb[MPTCP_PM_ADDR_ATTR_ID]); 1105 1106 if (tb[MPTCP_PM_ADDR_ATTR_FLAGS]) 1107 entry->flags = nla_get_u32(tb[MPTCP_PM_ADDR_ATTR_FLAGS]); 1108 1109 if (tb[MPTCP_PM_ADDR_ATTR_PORT]) { 1110 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) { 1111 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1112 "flags must have signal when using port"); 1113 return -EINVAL; 1114 } 1115 entry->addr.port = htons(nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_PORT])); 1116 } 1117 1118 return 0; 1119 } 1120 1121 static struct pm_nl_pernet *genl_info_pm_nl(struct genl_info *info) 1122 { 1123 return net_generic(genl_info_net(info), pm_nl_pernet_id); 1124 } 1125 1126 static int mptcp_nl_add_subflow_or_signal_addr(struct net *net) 1127 { 1128 struct mptcp_sock *msk; 1129 long s_slot = 0, s_num = 0; 1130 1131 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1132 struct sock *sk = (struct sock *)msk; 1133 1134 if (!READ_ONCE(msk->fully_established)) 1135 goto next; 1136 1137 lock_sock(sk); 1138 spin_lock_bh(&msk->pm.lock); 1139 mptcp_pm_create_subflow_or_signal_addr(msk); 1140 spin_unlock_bh(&msk->pm.lock); 1141 release_sock(sk); 1142 1143 next: 1144 sock_put(sk); 1145 cond_resched(); 1146 } 1147 1148 return 0; 1149 } 1150 1151 static int mptcp_nl_cmd_add_addr(struct sk_buff *skb, struct genl_info *info) 1152 { 1153 struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR]; 1154 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1155 struct mptcp_pm_addr_entry addr, *entry; 1156 int ret; 1157 1158 ret = mptcp_pm_parse_addr(attr, info, true, &addr); 1159 if (ret < 0) 1160 return ret; 1161 1162 entry = kmalloc(sizeof(*entry), GFP_KERNEL); 1163 if (!entry) { 1164 GENL_SET_ERR_MSG(info, "can't allocate addr"); 1165 return -ENOMEM; 1166 } 1167 1168 *entry = addr; 1169 if (entry->addr.port) { 1170 ret = mptcp_pm_nl_create_listen_socket(skb->sk, entry); 1171 if (ret) { 1172 GENL_SET_ERR_MSG(info, "create listen socket error"); 1173 kfree(entry); 1174 return ret; 1175 } 1176 } 1177 ret = mptcp_pm_nl_append_new_local_addr(pernet, entry); 1178 if (ret < 0) { 1179 GENL_SET_ERR_MSG(info, "too many addresses or duplicate one"); 1180 if (entry->lsk) 1181 sock_release(entry->lsk); 1182 kfree(entry); 1183 return ret; 1184 } 1185 1186 mptcp_nl_add_subflow_or_signal_addr(sock_net(skb->sk)); 1187 1188 return 0; 1189 } 1190 1191 static struct mptcp_pm_addr_entry * 1192 __lookup_addr_by_id(struct pm_nl_pernet *pernet, unsigned int id) 1193 { 1194 struct mptcp_pm_addr_entry *entry; 1195 1196 list_for_each_entry(entry, &pernet->local_addr_list, list) { 1197 if (entry->addr.id == id) 1198 return entry; 1199 } 1200 return NULL; 1201 } 1202 1203 int mptcp_pm_get_flags_and_ifindex_by_id(struct net *net, unsigned int id, 1204 u8 *flags, int *ifindex) 1205 { 1206 struct mptcp_pm_addr_entry *entry; 1207 1208 *flags = 0; 1209 *ifindex = 0; 1210 1211 if (id) { 1212 rcu_read_lock(); 1213 entry = __lookup_addr_by_id(net_generic(net, pm_nl_pernet_id), id); 1214 if (entry) { 1215 *flags = entry->flags; 1216 *ifindex = entry->ifindex; 1217 } 1218 rcu_read_unlock(); 1219 } 1220 1221 return 0; 1222 } 1223 1224 static bool remove_anno_list_by_saddr(struct mptcp_sock *msk, 1225 struct mptcp_addr_info *addr) 1226 { 1227 struct mptcp_pm_add_entry *entry; 1228 1229 entry = mptcp_pm_del_add_timer(msk, addr, false); 1230 if (entry) { 1231 list_del(&entry->list); 1232 kfree(entry); 1233 return true; 1234 } 1235 1236 return false; 1237 } 1238 1239 static bool mptcp_pm_remove_anno_addr(struct mptcp_sock *msk, 1240 struct mptcp_addr_info *addr, 1241 bool force) 1242 { 1243 struct mptcp_rm_list list = { .nr = 0 }; 1244 bool ret; 1245 1246 list.ids[list.nr++] = addr->id; 1247 1248 ret = remove_anno_list_by_saddr(msk, addr); 1249 if (ret || force) { 1250 spin_lock_bh(&msk->pm.lock); 1251 mptcp_pm_remove_addr(msk, &list); 1252 spin_unlock_bh(&msk->pm.lock); 1253 } 1254 return ret; 1255 } 1256 1257 static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net, 1258 struct mptcp_addr_info *addr) 1259 { 1260 struct mptcp_sock *msk; 1261 long s_slot = 0, s_num = 0; 1262 struct mptcp_rm_list list = { .nr = 0 }; 1263 1264 pr_debug("remove_id=%d", addr->id); 1265 1266 list.ids[list.nr++] = addr->id; 1267 1268 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1269 struct sock *sk = (struct sock *)msk; 1270 bool remove_subflow; 1271 1272 if (list_empty(&msk->conn_list)) { 1273 mptcp_pm_remove_anno_addr(msk, addr, false); 1274 goto next; 1275 } 1276 1277 lock_sock(sk); 1278 remove_subflow = lookup_subflow_by_saddr(&msk->conn_list, addr); 1279 mptcp_pm_remove_anno_addr(msk, addr, remove_subflow); 1280 if (remove_subflow) 1281 mptcp_pm_remove_subflow(msk, &list); 1282 release_sock(sk); 1283 1284 next: 1285 sock_put(sk); 1286 cond_resched(); 1287 } 1288 1289 return 0; 1290 } 1291 1292 /* caller must ensure the RCU grace period is already elapsed */ 1293 static void __mptcp_pm_release_addr_entry(struct mptcp_pm_addr_entry *entry) 1294 { 1295 if (entry->lsk) 1296 sock_release(entry->lsk); 1297 kfree(entry); 1298 } 1299 1300 static int mptcp_nl_remove_id_zero_address(struct net *net, 1301 struct mptcp_addr_info *addr) 1302 { 1303 struct mptcp_rm_list list = { .nr = 0 }; 1304 long s_slot = 0, s_num = 0; 1305 struct mptcp_sock *msk; 1306 1307 list.ids[list.nr++] = 0; 1308 1309 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1310 struct sock *sk = (struct sock *)msk; 1311 struct mptcp_addr_info msk_local; 1312 1313 if (list_empty(&msk->conn_list)) 1314 goto next; 1315 1316 local_address((struct sock_common *)msk, &msk_local); 1317 if (!addresses_equal(&msk_local, addr, addr->port)) 1318 goto next; 1319 1320 lock_sock(sk); 1321 spin_lock_bh(&msk->pm.lock); 1322 mptcp_pm_remove_addr(msk, &list); 1323 mptcp_pm_nl_rm_subflow_received(msk, &list); 1324 spin_unlock_bh(&msk->pm.lock); 1325 release_sock(sk); 1326 1327 next: 1328 sock_put(sk); 1329 cond_resched(); 1330 } 1331 1332 return 0; 1333 } 1334 1335 static int mptcp_nl_cmd_del_addr(struct sk_buff *skb, struct genl_info *info) 1336 { 1337 struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR]; 1338 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1339 struct mptcp_pm_addr_entry addr, *entry; 1340 unsigned int addr_max; 1341 int ret; 1342 1343 ret = mptcp_pm_parse_addr(attr, info, false, &addr); 1344 if (ret < 0) 1345 return ret; 1346 1347 /* the zero id address is special: the first address used by the msk 1348 * always gets such an id, so different subflows can have different zero 1349 * id addresses. Additionally zero id is not accounted for in id_bitmap. 1350 * Let's use an 'mptcp_rm_list' instead of the common remove code. 1351 */ 1352 if (addr.addr.id == 0) 1353 return mptcp_nl_remove_id_zero_address(sock_net(skb->sk), &addr.addr); 1354 1355 spin_lock_bh(&pernet->lock); 1356 entry = __lookup_addr_by_id(pernet, addr.addr.id); 1357 if (!entry) { 1358 GENL_SET_ERR_MSG(info, "address not found"); 1359 spin_unlock_bh(&pernet->lock); 1360 return -EINVAL; 1361 } 1362 if (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL) { 1363 addr_max = pernet->add_addr_signal_max; 1364 WRITE_ONCE(pernet->add_addr_signal_max, addr_max - 1); 1365 } 1366 if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) { 1367 addr_max = pernet->local_addr_max; 1368 WRITE_ONCE(pernet->local_addr_max, addr_max - 1); 1369 } 1370 1371 pernet->addrs--; 1372 list_del_rcu(&entry->list); 1373 __clear_bit(entry->addr.id, pernet->id_bitmap); 1374 spin_unlock_bh(&pernet->lock); 1375 1376 mptcp_nl_remove_subflow_and_signal_addr(sock_net(skb->sk), &entry->addr); 1377 synchronize_rcu(); 1378 __mptcp_pm_release_addr_entry(entry); 1379 1380 return ret; 1381 } 1382 1383 static void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk, 1384 struct list_head *rm_list) 1385 { 1386 struct mptcp_rm_list alist = { .nr = 0 }, slist = { .nr = 0 }; 1387 struct mptcp_pm_addr_entry *entry; 1388 1389 list_for_each_entry(entry, rm_list, list) { 1390 if (lookup_subflow_by_saddr(&msk->conn_list, &entry->addr) && 1391 alist.nr < MPTCP_RM_IDS_MAX && 1392 slist.nr < MPTCP_RM_IDS_MAX) { 1393 alist.ids[alist.nr++] = entry->addr.id; 1394 slist.ids[slist.nr++] = entry->addr.id; 1395 } else if (remove_anno_list_by_saddr(msk, &entry->addr) && 1396 alist.nr < MPTCP_RM_IDS_MAX) { 1397 alist.ids[alist.nr++] = entry->addr.id; 1398 } 1399 } 1400 1401 if (alist.nr) { 1402 spin_lock_bh(&msk->pm.lock); 1403 mptcp_pm_remove_addr(msk, &alist); 1404 spin_unlock_bh(&msk->pm.lock); 1405 } 1406 if (slist.nr) 1407 mptcp_pm_remove_subflow(msk, &slist); 1408 } 1409 1410 static void mptcp_nl_remove_addrs_list(struct net *net, 1411 struct list_head *rm_list) 1412 { 1413 long s_slot = 0, s_num = 0; 1414 struct mptcp_sock *msk; 1415 1416 if (list_empty(rm_list)) 1417 return; 1418 1419 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1420 struct sock *sk = (struct sock *)msk; 1421 1422 lock_sock(sk); 1423 mptcp_pm_remove_addrs_and_subflows(msk, rm_list); 1424 release_sock(sk); 1425 1426 sock_put(sk); 1427 cond_resched(); 1428 } 1429 } 1430 1431 /* caller must ensure the RCU grace period is already elapsed */ 1432 static void __flush_addrs(struct list_head *list) 1433 { 1434 while (!list_empty(list)) { 1435 struct mptcp_pm_addr_entry *cur; 1436 1437 cur = list_entry(list->next, 1438 struct mptcp_pm_addr_entry, list); 1439 list_del_rcu(&cur->list); 1440 __mptcp_pm_release_addr_entry(cur); 1441 } 1442 } 1443 1444 static void __reset_counters(struct pm_nl_pernet *pernet) 1445 { 1446 WRITE_ONCE(pernet->add_addr_signal_max, 0); 1447 WRITE_ONCE(pernet->add_addr_accept_max, 0); 1448 WRITE_ONCE(pernet->local_addr_max, 0); 1449 pernet->addrs = 0; 1450 } 1451 1452 static int mptcp_nl_cmd_flush_addrs(struct sk_buff *skb, struct genl_info *info) 1453 { 1454 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1455 LIST_HEAD(free_list); 1456 1457 spin_lock_bh(&pernet->lock); 1458 list_splice_init(&pernet->local_addr_list, &free_list); 1459 __reset_counters(pernet); 1460 pernet->next_id = 1; 1461 bitmap_zero(pernet->id_bitmap, MAX_ADDR_ID + 1); 1462 spin_unlock_bh(&pernet->lock); 1463 mptcp_nl_remove_addrs_list(sock_net(skb->sk), &free_list); 1464 synchronize_rcu(); 1465 __flush_addrs(&free_list); 1466 return 0; 1467 } 1468 1469 static int mptcp_nl_fill_addr(struct sk_buff *skb, 1470 struct mptcp_pm_addr_entry *entry) 1471 { 1472 struct mptcp_addr_info *addr = &entry->addr; 1473 struct nlattr *attr; 1474 1475 attr = nla_nest_start(skb, MPTCP_PM_ATTR_ADDR); 1476 if (!attr) 1477 return -EMSGSIZE; 1478 1479 if (nla_put_u16(skb, MPTCP_PM_ADDR_ATTR_FAMILY, addr->family)) 1480 goto nla_put_failure; 1481 if (nla_put_u16(skb, MPTCP_PM_ADDR_ATTR_PORT, ntohs(addr->port))) 1482 goto nla_put_failure; 1483 if (nla_put_u8(skb, MPTCP_PM_ADDR_ATTR_ID, addr->id)) 1484 goto nla_put_failure; 1485 if (nla_put_u32(skb, MPTCP_PM_ADDR_ATTR_FLAGS, entry->flags)) 1486 goto nla_put_failure; 1487 if (entry->ifindex && 1488 nla_put_s32(skb, MPTCP_PM_ADDR_ATTR_IF_IDX, entry->ifindex)) 1489 goto nla_put_failure; 1490 1491 if (addr->family == AF_INET && 1492 nla_put_in_addr(skb, MPTCP_PM_ADDR_ATTR_ADDR4, 1493 addr->addr.s_addr)) 1494 goto nla_put_failure; 1495 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1496 else if (addr->family == AF_INET6 && 1497 nla_put_in6_addr(skb, MPTCP_PM_ADDR_ATTR_ADDR6, &addr->addr6)) 1498 goto nla_put_failure; 1499 #endif 1500 nla_nest_end(skb, attr); 1501 return 0; 1502 1503 nla_put_failure: 1504 nla_nest_cancel(skb, attr); 1505 return -EMSGSIZE; 1506 } 1507 1508 static int mptcp_nl_cmd_get_addr(struct sk_buff *skb, struct genl_info *info) 1509 { 1510 struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR]; 1511 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1512 struct mptcp_pm_addr_entry addr, *entry; 1513 struct sk_buff *msg; 1514 void *reply; 1515 int ret; 1516 1517 ret = mptcp_pm_parse_addr(attr, info, false, &addr); 1518 if (ret < 0) 1519 return ret; 1520 1521 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 1522 if (!msg) 1523 return -ENOMEM; 1524 1525 reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0, 1526 info->genlhdr->cmd); 1527 if (!reply) { 1528 GENL_SET_ERR_MSG(info, "not enough space in Netlink message"); 1529 ret = -EMSGSIZE; 1530 goto fail; 1531 } 1532 1533 spin_lock_bh(&pernet->lock); 1534 entry = __lookup_addr_by_id(pernet, addr.addr.id); 1535 if (!entry) { 1536 GENL_SET_ERR_MSG(info, "address not found"); 1537 ret = -EINVAL; 1538 goto unlock_fail; 1539 } 1540 1541 ret = mptcp_nl_fill_addr(msg, entry); 1542 if (ret) 1543 goto unlock_fail; 1544 1545 genlmsg_end(msg, reply); 1546 ret = genlmsg_reply(msg, info); 1547 spin_unlock_bh(&pernet->lock); 1548 return ret; 1549 1550 unlock_fail: 1551 spin_unlock_bh(&pernet->lock); 1552 1553 fail: 1554 nlmsg_free(msg); 1555 return ret; 1556 } 1557 1558 static int mptcp_nl_cmd_dump_addrs(struct sk_buff *msg, 1559 struct netlink_callback *cb) 1560 { 1561 struct net *net = sock_net(msg->sk); 1562 struct mptcp_pm_addr_entry *entry; 1563 struct pm_nl_pernet *pernet; 1564 int id = cb->args[0]; 1565 void *hdr; 1566 int i; 1567 1568 pernet = net_generic(net, pm_nl_pernet_id); 1569 1570 spin_lock_bh(&pernet->lock); 1571 for (i = id; i < MAX_ADDR_ID + 1; i++) { 1572 if (test_bit(i, pernet->id_bitmap)) { 1573 entry = __lookup_addr_by_id(pernet, i); 1574 if (!entry) 1575 break; 1576 1577 if (entry->addr.id <= id) 1578 continue; 1579 1580 hdr = genlmsg_put(msg, NETLINK_CB(cb->skb).portid, 1581 cb->nlh->nlmsg_seq, &mptcp_genl_family, 1582 NLM_F_MULTI, MPTCP_PM_CMD_GET_ADDR); 1583 if (!hdr) 1584 break; 1585 1586 if (mptcp_nl_fill_addr(msg, entry) < 0) { 1587 genlmsg_cancel(msg, hdr); 1588 break; 1589 } 1590 1591 id = entry->addr.id; 1592 genlmsg_end(msg, hdr); 1593 } 1594 } 1595 spin_unlock_bh(&pernet->lock); 1596 1597 cb->args[0] = id; 1598 return msg->len; 1599 } 1600 1601 static int parse_limit(struct genl_info *info, int id, unsigned int *limit) 1602 { 1603 struct nlattr *attr = info->attrs[id]; 1604 1605 if (!attr) 1606 return 0; 1607 1608 *limit = nla_get_u32(attr); 1609 if (*limit > MPTCP_PM_ADDR_MAX) { 1610 GENL_SET_ERR_MSG(info, "limit greater than maximum"); 1611 return -EINVAL; 1612 } 1613 return 0; 1614 } 1615 1616 static int 1617 mptcp_nl_cmd_set_limits(struct sk_buff *skb, struct genl_info *info) 1618 { 1619 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1620 unsigned int rcv_addrs, subflows; 1621 int ret; 1622 1623 spin_lock_bh(&pernet->lock); 1624 rcv_addrs = pernet->add_addr_accept_max; 1625 ret = parse_limit(info, MPTCP_PM_ATTR_RCV_ADD_ADDRS, &rcv_addrs); 1626 if (ret) 1627 goto unlock; 1628 1629 subflows = pernet->subflows_max; 1630 ret = parse_limit(info, MPTCP_PM_ATTR_SUBFLOWS, &subflows); 1631 if (ret) 1632 goto unlock; 1633 1634 WRITE_ONCE(pernet->add_addr_accept_max, rcv_addrs); 1635 WRITE_ONCE(pernet->subflows_max, subflows); 1636 1637 unlock: 1638 spin_unlock_bh(&pernet->lock); 1639 return ret; 1640 } 1641 1642 static int 1643 mptcp_nl_cmd_get_limits(struct sk_buff *skb, struct genl_info *info) 1644 { 1645 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1646 struct sk_buff *msg; 1647 void *reply; 1648 1649 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 1650 if (!msg) 1651 return -ENOMEM; 1652 1653 reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0, 1654 MPTCP_PM_CMD_GET_LIMITS); 1655 if (!reply) 1656 goto fail; 1657 1658 if (nla_put_u32(msg, MPTCP_PM_ATTR_RCV_ADD_ADDRS, 1659 READ_ONCE(pernet->add_addr_accept_max))) 1660 goto fail; 1661 1662 if (nla_put_u32(msg, MPTCP_PM_ATTR_SUBFLOWS, 1663 READ_ONCE(pernet->subflows_max))) 1664 goto fail; 1665 1666 genlmsg_end(msg, reply); 1667 return genlmsg_reply(msg, info); 1668 1669 fail: 1670 GENL_SET_ERR_MSG(info, "not enough space in Netlink message"); 1671 nlmsg_free(msg); 1672 return -EMSGSIZE; 1673 } 1674 1675 static int mptcp_nl_addr_backup(struct net *net, 1676 struct mptcp_addr_info *addr, 1677 u8 bkup) 1678 { 1679 long s_slot = 0, s_num = 0; 1680 struct mptcp_sock *msk; 1681 int ret = -EINVAL; 1682 1683 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1684 struct sock *sk = (struct sock *)msk; 1685 1686 if (list_empty(&msk->conn_list)) 1687 goto next; 1688 1689 lock_sock(sk); 1690 spin_lock_bh(&msk->pm.lock); 1691 ret = mptcp_pm_nl_mp_prio_send_ack(msk, addr, bkup); 1692 spin_unlock_bh(&msk->pm.lock); 1693 release_sock(sk); 1694 1695 next: 1696 sock_put(sk); 1697 cond_resched(); 1698 } 1699 1700 return ret; 1701 } 1702 1703 static int mptcp_nl_cmd_set_flags(struct sk_buff *skb, struct genl_info *info) 1704 { 1705 struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR]; 1706 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1707 struct mptcp_pm_addr_entry addr, *entry; 1708 struct net *net = sock_net(skb->sk); 1709 u8 bkup = 0; 1710 int ret; 1711 1712 ret = mptcp_pm_parse_addr(attr, info, true, &addr); 1713 if (ret < 0) 1714 return ret; 1715 1716 if (addr.flags & MPTCP_PM_ADDR_FLAG_BACKUP) 1717 bkup = 1; 1718 1719 list_for_each_entry(entry, &pernet->local_addr_list, list) { 1720 if (addresses_equal(&entry->addr, &addr.addr, true)) { 1721 ret = mptcp_nl_addr_backup(net, &entry->addr, bkup); 1722 if (ret) 1723 return ret; 1724 1725 if (bkup) 1726 entry->flags |= MPTCP_PM_ADDR_FLAG_BACKUP; 1727 else 1728 entry->flags &= ~MPTCP_PM_ADDR_FLAG_BACKUP; 1729 } 1730 } 1731 1732 return 0; 1733 } 1734 1735 static void mptcp_nl_mcast_send(struct net *net, struct sk_buff *nlskb, gfp_t gfp) 1736 { 1737 genlmsg_multicast_netns(&mptcp_genl_family, net, 1738 nlskb, 0, MPTCP_PM_EV_GRP_OFFSET, gfp); 1739 } 1740 1741 static int mptcp_event_add_subflow(struct sk_buff *skb, const struct sock *ssk) 1742 { 1743 const struct inet_sock *issk = inet_sk(ssk); 1744 const struct mptcp_subflow_context *sf; 1745 1746 if (nla_put_u16(skb, MPTCP_ATTR_FAMILY, ssk->sk_family)) 1747 return -EMSGSIZE; 1748 1749 switch (ssk->sk_family) { 1750 case AF_INET: 1751 if (nla_put_in_addr(skb, MPTCP_ATTR_SADDR4, issk->inet_saddr)) 1752 return -EMSGSIZE; 1753 if (nla_put_in_addr(skb, MPTCP_ATTR_DADDR4, issk->inet_daddr)) 1754 return -EMSGSIZE; 1755 break; 1756 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1757 case AF_INET6: { 1758 const struct ipv6_pinfo *np = inet6_sk(ssk); 1759 1760 if (nla_put_in6_addr(skb, MPTCP_ATTR_SADDR6, &np->saddr)) 1761 return -EMSGSIZE; 1762 if (nla_put_in6_addr(skb, MPTCP_ATTR_DADDR6, &ssk->sk_v6_daddr)) 1763 return -EMSGSIZE; 1764 break; 1765 } 1766 #endif 1767 default: 1768 WARN_ON_ONCE(1); 1769 return -EMSGSIZE; 1770 } 1771 1772 if (nla_put_be16(skb, MPTCP_ATTR_SPORT, issk->inet_sport)) 1773 return -EMSGSIZE; 1774 if (nla_put_be16(skb, MPTCP_ATTR_DPORT, issk->inet_dport)) 1775 return -EMSGSIZE; 1776 1777 sf = mptcp_subflow_ctx(ssk); 1778 if (WARN_ON_ONCE(!sf)) 1779 return -EINVAL; 1780 1781 if (nla_put_u8(skb, MPTCP_ATTR_LOC_ID, sf->local_id)) 1782 return -EMSGSIZE; 1783 1784 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, sf->remote_id)) 1785 return -EMSGSIZE; 1786 1787 return 0; 1788 } 1789 1790 static int mptcp_event_put_token_and_ssk(struct sk_buff *skb, 1791 const struct mptcp_sock *msk, 1792 const struct sock *ssk) 1793 { 1794 const struct sock *sk = (const struct sock *)msk; 1795 const struct mptcp_subflow_context *sf; 1796 u8 sk_err; 1797 1798 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token)) 1799 return -EMSGSIZE; 1800 1801 if (mptcp_event_add_subflow(skb, ssk)) 1802 return -EMSGSIZE; 1803 1804 sf = mptcp_subflow_ctx(ssk); 1805 if (WARN_ON_ONCE(!sf)) 1806 return -EINVAL; 1807 1808 if (nla_put_u8(skb, MPTCP_ATTR_BACKUP, sf->backup)) 1809 return -EMSGSIZE; 1810 1811 if (ssk->sk_bound_dev_if && 1812 nla_put_s32(skb, MPTCP_ATTR_IF_IDX, ssk->sk_bound_dev_if)) 1813 return -EMSGSIZE; 1814 1815 sk_err = ssk->sk_err; 1816 if (sk_err && sk->sk_state == TCP_ESTABLISHED && 1817 nla_put_u8(skb, MPTCP_ATTR_ERROR, sk_err)) 1818 return -EMSGSIZE; 1819 1820 return 0; 1821 } 1822 1823 static int mptcp_event_sub_established(struct sk_buff *skb, 1824 const struct mptcp_sock *msk, 1825 const struct sock *ssk) 1826 { 1827 return mptcp_event_put_token_and_ssk(skb, msk, ssk); 1828 } 1829 1830 static int mptcp_event_sub_closed(struct sk_buff *skb, 1831 const struct mptcp_sock *msk, 1832 const struct sock *ssk) 1833 { 1834 const struct mptcp_subflow_context *sf; 1835 1836 if (mptcp_event_put_token_and_ssk(skb, msk, ssk)) 1837 return -EMSGSIZE; 1838 1839 sf = mptcp_subflow_ctx(ssk); 1840 if (!sf->reset_seen) 1841 return 0; 1842 1843 if (nla_put_u32(skb, MPTCP_ATTR_RESET_REASON, sf->reset_reason)) 1844 return -EMSGSIZE; 1845 1846 if (nla_put_u32(skb, MPTCP_ATTR_RESET_FLAGS, sf->reset_transient)) 1847 return -EMSGSIZE; 1848 1849 return 0; 1850 } 1851 1852 static int mptcp_event_created(struct sk_buff *skb, 1853 const struct mptcp_sock *msk, 1854 const struct sock *ssk) 1855 { 1856 int err = nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token); 1857 1858 if (err) 1859 return err; 1860 1861 return mptcp_event_add_subflow(skb, ssk); 1862 } 1863 1864 void mptcp_event_addr_removed(const struct mptcp_sock *msk, uint8_t id) 1865 { 1866 struct net *net = sock_net((const struct sock *)msk); 1867 struct nlmsghdr *nlh; 1868 struct sk_buff *skb; 1869 1870 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 1871 return; 1872 1873 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); 1874 if (!skb) 1875 return; 1876 1877 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, MPTCP_EVENT_REMOVED); 1878 if (!nlh) 1879 goto nla_put_failure; 1880 1881 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token)) 1882 goto nla_put_failure; 1883 1884 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, id)) 1885 goto nla_put_failure; 1886 1887 genlmsg_end(skb, nlh); 1888 mptcp_nl_mcast_send(net, skb, GFP_ATOMIC); 1889 return; 1890 1891 nla_put_failure: 1892 kfree_skb(skb); 1893 } 1894 1895 void mptcp_event_addr_announced(const struct mptcp_sock *msk, 1896 const struct mptcp_addr_info *info) 1897 { 1898 struct net *net = sock_net((const struct sock *)msk); 1899 struct nlmsghdr *nlh; 1900 struct sk_buff *skb; 1901 1902 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 1903 return; 1904 1905 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); 1906 if (!skb) 1907 return; 1908 1909 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, 1910 MPTCP_EVENT_ANNOUNCED); 1911 if (!nlh) 1912 goto nla_put_failure; 1913 1914 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token)) 1915 goto nla_put_failure; 1916 1917 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, info->id)) 1918 goto nla_put_failure; 1919 1920 if (nla_put_be16(skb, MPTCP_ATTR_DPORT, info->port)) 1921 goto nla_put_failure; 1922 1923 switch (info->family) { 1924 case AF_INET: 1925 if (nla_put_in_addr(skb, MPTCP_ATTR_DADDR4, info->addr.s_addr)) 1926 goto nla_put_failure; 1927 break; 1928 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1929 case AF_INET6: 1930 if (nla_put_in6_addr(skb, MPTCP_ATTR_DADDR6, &info->addr6)) 1931 goto nla_put_failure; 1932 break; 1933 #endif 1934 default: 1935 WARN_ON_ONCE(1); 1936 goto nla_put_failure; 1937 } 1938 1939 genlmsg_end(skb, nlh); 1940 mptcp_nl_mcast_send(net, skb, GFP_ATOMIC); 1941 return; 1942 1943 nla_put_failure: 1944 kfree_skb(skb); 1945 } 1946 1947 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk, 1948 const struct sock *ssk, gfp_t gfp) 1949 { 1950 struct net *net = sock_net((const struct sock *)msk); 1951 struct nlmsghdr *nlh; 1952 struct sk_buff *skb; 1953 1954 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 1955 return; 1956 1957 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, gfp); 1958 if (!skb) 1959 return; 1960 1961 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, type); 1962 if (!nlh) 1963 goto nla_put_failure; 1964 1965 switch (type) { 1966 case MPTCP_EVENT_UNSPEC: 1967 WARN_ON_ONCE(1); 1968 break; 1969 case MPTCP_EVENT_CREATED: 1970 case MPTCP_EVENT_ESTABLISHED: 1971 if (mptcp_event_created(skb, msk, ssk) < 0) 1972 goto nla_put_failure; 1973 break; 1974 case MPTCP_EVENT_CLOSED: 1975 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token) < 0) 1976 goto nla_put_failure; 1977 break; 1978 case MPTCP_EVENT_ANNOUNCED: 1979 case MPTCP_EVENT_REMOVED: 1980 /* call mptcp_event_addr_announced()/removed instead */ 1981 WARN_ON_ONCE(1); 1982 break; 1983 case MPTCP_EVENT_SUB_ESTABLISHED: 1984 case MPTCP_EVENT_SUB_PRIORITY: 1985 if (mptcp_event_sub_established(skb, msk, ssk) < 0) 1986 goto nla_put_failure; 1987 break; 1988 case MPTCP_EVENT_SUB_CLOSED: 1989 if (mptcp_event_sub_closed(skb, msk, ssk) < 0) 1990 goto nla_put_failure; 1991 break; 1992 } 1993 1994 genlmsg_end(skb, nlh); 1995 mptcp_nl_mcast_send(net, skb, gfp); 1996 return; 1997 1998 nla_put_failure: 1999 kfree_skb(skb); 2000 } 2001 2002 static const struct genl_small_ops mptcp_pm_ops[] = { 2003 { 2004 .cmd = MPTCP_PM_CMD_ADD_ADDR, 2005 .doit = mptcp_nl_cmd_add_addr, 2006 .flags = GENL_ADMIN_PERM, 2007 }, 2008 { 2009 .cmd = MPTCP_PM_CMD_DEL_ADDR, 2010 .doit = mptcp_nl_cmd_del_addr, 2011 .flags = GENL_ADMIN_PERM, 2012 }, 2013 { 2014 .cmd = MPTCP_PM_CMD_FLUSH_ADDRS, 2015 .doit = mptcp_nl_cmd_flush_addrs, 2016 .flags = GENL_ADMIN_PERM, 2017 }, 2018 { 2019 .cmd = MPTCP_PM_CMD_GET_ADDR, 2020 .doit = mptcp_nl_cmd_get_addr, 2021 .dumpit = mptcp_nl_cmd_dump_addrs, 2022 }, 2023 { 2024 .cmd = MPTCP_PM_CMD_SET_LIMITS, 2025 .doit = mptcp_nl_cmd_set_limits, 2026 .flags = GENL_ADMIN_PERM, 2027 }, 2028 { 2029 .cmd = MPTCP_PM_CMD_GET_LIMITS, 2030 .doit = mptcp_nl_cmd_get_limits, 2031 }, 2032 { 2033 .cmd = MPTCP_PM_CMD_SET_FLAGS, 2034 .doit = mptcp_nl_cmd_set_flags, 2035 .flags = GENL_ADMIN_PERM, 2036 }, 2037 }; 2038 2039 static struct genl_family mptcp_genl_family __ro_after_init = { 2040 .name = MPTCP_PM_NAME, 2041 .version = MPTCP_PM_VER, 2042 .maxattr = MPTCP_PM_ATTR_MAX, 2043 .policy = mptcp_pm_policy, 2044 .netnsok = true, 2045 .module = THIS_MODULE, 2046 .small_ops = mptcp_pm_ops, 2047 .n_small_ops = ARRAY_SIZE(mptcp_pm_ops), 2048 .mcgrps = mptcp_pm_mcgrps, 2049 .n_mcgrps = ARRAY_SIZE(mptcp_pm_mcgrps), 2050 }; 2051 2052 static int __net_init pm_nl_init_net(struct net *net) 2053 { 2054 struct pm_nl_pernet *pernet = net_generic(net, pm_nl_pernet_id); 2055 2056 INIT_LIST_HEAD_RCU(&pernet->local_addr_list); 2057 pernet->next_id = 1; 2058 pernet->stale_loss_cnt = 4; 2059 spin_lock_init(&pernet->lock); 2060 2061 /* No need to initialize other pernet fields, the struct is zeroed at 2062 * allocation time. 2063 */ 2064 2065 return 0; 2066 } 2067 2068 static void __net_exit pm_nl_exit_net(struct list_head *net_list) 2069 { 2070 struct net *net; 2071 2072 list_for_each_entry(net, net_list, exit_list) { 2073 struct pm_nl_pernet *pernet = net_generic(net, pm_nl_pernet_id); 2074 2075 /* net is removed from namespace list, can't race with 2076 * other modifiers, also netns core already waited for a 2077 * RCU grace period. 2078 */ 2079 __flush_addrs(&pernet->local_addr_list); 2080 } 2081 } 2082 2083 static struct pernet_operations mptcp_pm_pernet_ops = { 2084 .init = pm_nl_init_net, 2085 .exit_batch = pm_nl_exit_net, 2086 .id = &pm_nl_pernet_id, 2087 .size = sizeof(struct pm_nl_pernet), 2088 }; 2089 2090 void __init mptcp_pm_nl_init(void) 2091 { 2092 if (register_pernet_subsys(&mptcp_pm_pernet_ops) < 0) 2093 panic("Failed to register MPTCP PM pernet subsystem.\n"); 2094 2095 if (genl_register_family(&mptcp_genl_family)) 2096 panic("Failed to register MPTCP PM netlink family\n"); 2097 } 2098