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 struct pm_nl_pernet { 42 /* protects pernet updates */ 43 spinlock_t lock; 44 struct list_head local_addr_list; 45 unsigned int addrs; 46 unsigned int stale_loss_cnt; 47 unsigned int add_addr_signal_max; 48 unsigned int add_addr_accept_max; 49 unsigned int local_addr_max; 50 unsigned int subflows_max; 51 unsigned int next_id; 52 DECLARE_BITMAP(id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); 53 }; 54 55 #define MPTCP_PM_ADDR_MAX 8 56 #define ADD_ADDR_RETRANS_MAX 3 57 58 static bool addresses_equal(const struct mptcp_addr_info *a, 59 const struct mptcp_addr_info *b, bool use_port) 60 { 61 bool addr_equals = false; 62 63 if (a->family == b->family) { 64 if (a->family == AF_INET) 65 addr_equals = a->addr.s_addr == b->addr.s_addr; 66 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 67 else 68 addr_equals = !ipv6_addr_cmp(&a->addr6, &b->addr6); 69 } else if (a->family == AF_INET) { 70 if (ipv6_addr_v4mapped(&b->addr6)) 71 addr_equals = a->addr.s_addr == b->addr6.s6_addr32[3]; 72 } else if (b->family == AF_INET) { 73 if (ipv6_addr_v4mapped(&a->addr6)) 74 addr_equals = a->addr6.s6_addr32[3] == b->addr.s_addr; 75 #endif 76 } 77 78 if (!addr_equals) 79 return false; 80 if (!use_port) 81 return true; 82 83 return a->port == b->port; 84 } 85 86 static bool address_zero(const struct mptcp_addr_info *addr) 87 { 88 struct mptcp_addr_info zero; 89 90 memset(&zero, 0, sizeof(zero)); 91 zero.family = addr->family; 92 93 return addresses_equal(addr, &zero, true); 94 } 95 96 static void local_address(const struct sock_common *skc, 97 struct mptcp_addr_info *addr) 98 { 99 addr->family = skc->skc_family; 100 addr->port = htons(skc->skc_num); 101 if (addr->family == AF_INET) 102 addr->addr.s_addr = skc->skc_rcv_saddr; 103 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 104 else if (addr->family == AF_INET6) 105 addr->addr6 = skc->skc_v6_rcv_saddr; 106 #endif 107 } 108 109 static void remote_address(const struct sock_common *skc, 110 struct mptcp_addr_info *addr) 111 { 112 addr->family = skc->skc_family; 113 addr->port = skc->skc_dport; 114 if (addr->family == AF_INET) 115 addr->addr.s_addr = skc->skc_daddr; 116 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 117 else if (addr->family == AF_INET6) 118 addr->addr6 = skc->skc_v6_daddr; 119 #endif 120 } 121 122 static bool lookup_subflow_by_saddr(const struct list_head *list, 123 struct mptcp_addr_info *saddr) 124 { 125 struct mptcp_subflow_context *subflow; 126 struct mptcp_addr_info cur; 127 struct sock_common *skc; 128 129 list_for_each_entry(subflow, list, node) { 130 skc = (struct sock_common *)mptcp_subflow_tcp_sock(subflow); 131 132 local_address(skc, &cur); 133 if (addresses_equal(&cur, saddr, saddr->port)) 134 return true; 135 } 136 137 return false; 138 } 139 140 static bool lookup_subflow_by_daddr(const struct list_head *list, 141 struct mptcp_addr_info *daddr) 142 { 143 struct mptcp_subflow_context *subflow; 144 struct mptcp_addr_info cur; 145 struct sock_common *skc; 146 147 list_for_each_entry(subflow, list, node) { 148 skc = (struct sock_common *)mptcp_subflow_tcp_sock(subflow); 149 150 remote_address(skc, &cur); 151 if (addresses_equal(&cur, daddr, daddr->port)) 152 return true; 153 } 154 155 return false; 156 } 157 158 static struct mptcp_pm_addr_entry * 159 select_local_address(const struct pm_nl_pernet *pernet, 160 struct mptcp_sock *msk) 161 { 162 struct mptcp_pm_addr_entry *entry, *ret = NULL; 163 struct sock *sk = (struct sock *)msk; 164 165 msk_owned_by_me(msk); 166 167 rcu_read_lock(); 168 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 169 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW)) 170 continue; 171 172 if (!test_bit(entry->addr.id, msk->pm.id_avail_bitmap)) 173 continue; 174 175 if (entry->addr.family != sk->sk_family) { 176 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 177 if ((entry->addr.family == AF_INET && 178 !ipv6_addr_v4mapped(&sk->sk_v6_daddr)) || 179 (sk->sk_family == AF_INET && 180 !ipv6_addr_v4mapped(&entry->addr.addr6))) 181 #endif 182 continue; 183 } 184 185 ret = entry; 186 break; 187 } 188 rcu_read_unlock(); 189 return ret; 190 } 191 192 static struct mptcp_pm_addr_entry * 193 select_signal_address(struct pm_nl_pernet *pernet, struct mptcp_sock *msk) 194 { 195 struct mptcp_pm_addr_entry *entry, *ret = NULL; 196 197 rcu_read_lock(); 198 /* do not keep any additional per socket state, just signal 199 * the address list in order. 200 * Note: removal from the local address list during the msk life-cycle 201 * can lead to additional addresses not being announced. 202 */ 203 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 204 if (!test_bit(entry->addr.id, msk->pm.id_avail_bitmap)) 205 continue; 206 207 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) 208 continue; 209 210 ret = entry; 211 break; 212 } 213 rcu_read_unlock(); 214 return ret; 215 } 216 217 unsigned int mptcp_pm_get_add_addr_signal_max(struct mptcp_sock *msk) 218 { 219 struct pm_nl_pernet *pernet; 220 221 pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id); 222 return READ_ONCE(pernet->add_addr_signal_max); 223 } 224 EXPORT_SYMBOL_GPL(mptcp_pm_get_add_addr_signal_max); 225 226 unsigned int mptcp_pm_get_add_addr_accept_max(struct mptcp_sock *msk) 227 { 228 struct pm_nl_pernet *pernet; 229 230 pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id); 231 return READ_ONCE(pernet->add_addr_accept_max); 232 } 233 EXPORT_SYMBOL_GPL(mptcp_pm_get_add_addr_accept_max); 234 235 unsigned int mptcp_pm_get_subflows_max(struct mptcp_sock *msk) 236 { 237 struct pm_nl_pernet *pernet; 238 239 pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id); 240 return READ_ONCE(pernet->subflows_max); 241 } 242 EXPORT_SYMBOL_GPL(mptcp_pm_get_subflows_max); 243 244 unsigned int mptcp_pm_get_local_addr_max(struct mptcp_sock *msk) 245 { 246 struct pm_nl_pernet *pernet; 247 248 pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id); 249 return READ_ONCE(pernet->local_addr_max); 250 } 251 EXPORT_SYMBOL_GPL(mptcp_pm_get_local_addr_max); 252 253 bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk) 254 { 255 struct pm_nl_pernet *pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id); 256 257 if (msk->pm.subflows == mptcp_pm_get_subflows_max(msk) || 258 (find_next_and_bit(pernet->id_bitmap, msk->pm.id_avail_bitmap, 259 MPTCP_PM_MAX_ADDR_ID + 1, 0) == MPTCP_PM_MAX_ADDR_ID + 1)) { 260 WRITE_ONCE(msk->pm.work_pending, false); 261 return false; 262 } 263 return true; 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 bool deny_id0 = READ_ONCE(msk->pm.remote_deny_join_id0); 433 struct sock *sk = (struct sock *)msk, *ssk; 434 struct mptcp_subflow_context *subflow; 435 struct mptcp_addr_info remote = { 0 }; 436 unsigned int subflows_max; 437 int i = 0; 438 439 subflows_max = mptcp_pm_get_subflows_max(msk); 440 remote_address((struct sock_common *)sk, &remote); 441 442 /* Non-fullmesh endpoint, fill in the single entry 443 * corresponding to the primary MPC subflow remote address 444 */ 445 if (!fullmesh) { 446 if (deny_id0) 447 return 0; 448 449 msk->pm.subflows++; 450 addrs[i++] = remote; 451 } else { 452 mptcp_for_each_subflow(msk, subflow) { 453 ssk = mptcp_subflow_tcp_sock(subflow); 454 remote_address((struct sock_common *)ssk, &addrs[i]); 455 if (deny_id0 && addresses_equal(&addrs[i], &remote, false)) 456 continue; 457 458 if (!lookup_address_in_vec(addrs, i, &addrs[i]) && 459 msk->pm.subflows < subflows_max) { 460 msk->pm.subflows++; 461 i++; 462 } 463 } 464 } 465 466 return i; 467 } 468 469 static struct mptcp_pm_addr_entry * 470 __lookup_addr_by_id(struct pm_nl_pernet *pernet, unsigned int id) 471 { 472 struct mptcp_pm_addr_entry *entry; 473 474 list_for_each_entry(entry, &pernet->local_addr_list, list) { 475 if (entry->addr.id == id) 476 return entry; 477 } 478 return NULL; 479 } 480 481 static struct mptcp_pm_addr_entry * 482 __lookup_addr(struct pm_nl_pernet *pernet, const struct mptcp_addr_info *info, 483 bool lookup_by_id) 484 { 485 struct mptcp_pm_addr_entry *entry; 486 487 list_for_each_entry(entry, &pernet->local_addr_list, list) { 488 if ((!lookup_by_id && addresses_equal(&entry->addr, info, true)) || 489 (lookup_by_id && entry->addr.id == info->id)) 490 return entry; 491 } 492 return NULL; 493 } 494 495 static int 496 lookup_id_by_addr(struct pm_nl_pernet *pernet, const struct mptcp_addr_info *addr) 497 { 498 struct mptcp_pm_addr_entry *entry; 499 int ret = -1; 500 501 rcu_read_lock(); 502 list_for_each_entry(entry, &pernet->local_addr_list, list) { 503 if (addresses_equal(&entry->addr, addr, entry->addr.port)) { 504 ret = entry->addr.id; 505 break; 506 } 507 } 508 rcu_read_unlock(); 509 return ret; 510 } 511 512 static void mptcp_pm_create_subflow_or_signal_addr(struct mptcp_sock *msk) 513 { 514 struct sock *sk = (struct sock *)msk; 515 struct mptcp_pm_addr_entry *local; 516 unsigned int add_addr_signal_max; 517 unsigned int local_addr_max; 518 struct pm_nl_pernet *pernet; 519 unsigned int subflows_max; 520 521 pernet = net_generic(sock_net(sk), pm_nl_pernet_id); 522 523 add_addr_signal_max = mptcp_pm_get_add_addr_signal_max(msk); 524 local_addr_max = mptcp_pm_get_local_addr_max(msk); 525 subflows_max = mptcp_pm_get_subflows_max(msk); 526 527 /* do lazy endpoint usage accounting for the MPC subflows */ 528 if (unlikely(!(msk->pm.status & BIT(MPTCP_PM_MPC_ENDPOINT_ACCOUNTED))) && msk->first) { 529 struct mptcp_addr_info mpc_addr; 530 int mpc_id; 531 532 local_address((struct sock_common *)msk->first, &mpc_addr); 533 mpc_id = lookup_id_by_addr(pernet, &mpc_addr); 534 if (mpc_id >= 0) 535 __clear_bit(mpc_id, msk->pm.id_avail_bitmap); 536 537 msk->pm.status |= BIT(MPTCP_PM_MPC_ENDPOINT_ACCOUNTED); 538 } 539 540 pr_debug("local %d:%d signal %d:%d subflows %d:%d\n", 541 msk->pm.local_addr_used, local_addr_max, 542 msk->pm.add_addr_signaled, add_addr_signal_max, 543 msk->pm.subflows, subflows_max); 544 545 /* check first for announce */ 546 if (msk->pm.add_addr_signaled < add_addr_signal_max) { 547 local = select_signal_address(pernet, msk); 548 549 if (local) { 550 if (mptcp_pm_alloc_anno_list(msk, local)) { 551 __clear_bit(local->addr.id, msk->pm.id_avail_bitmap); 552 msk->pm.add_addr_signaled++; 553 mptcp_pm_announce_addr(msk, &local->addr, false); 554 mptcp_pm_nl_addr_send_ack(msk); 555 } 556 } 557 } 558 559 /* check if should create a new subflow */ 560 while (msk->pm.local_addr_used < local_addr_max && 561 msk->pm.subflows < subflows_max) { 562 struct mptcp_addr_info addrs[MPTCP_PM_ADDR_MAX]; 563 bool fullmesh; 564 int i, nr; 565 566 local = select_local_address(pernet, msk); 567 if (!local) 568 break; 569 570 fullmesh = !!(local->flags & MPTCP_PM_ADDR_FLAG_FULLMESH); 571 572 msk->pm.local_addr_used++; 573 nr = fill_remote_addresses_vec(msk, fullmesh, addrs); 574 if (nr) 575 __clear_bit(local->addr.id, msk->pm.id_avail_bitmap); 576 spin_unlock_bh(&msk->pm.lock); 577 for (i = 0; i < nr; i++) 578 __mptcp_subflow_connect(sk, &local->addr, &addrs[i]); 579 spin_lock_bh(&msk->pm.lock); 580 } 581 mptcp_pm_nl_check_work_pending(msk); 582 } 583 584 static void mptcp_pm_nl_fully_established(struct mptcp_sock *msk) 585 { 586 mptcp_pm_create_subflow_or_signal_addr(msk); 587 } 588 589 static void mptcp_pm_nl_subflow_established(struct mptcp_sock *msk) 590 { 591 mptcp_pm_create_subflow_or_signal_addr(msk); 592 } 593 594 /* Fill all the local addresses into the array addrs[], 595 * and return the array size. 596 */ 597 static unsigned int fill_local_addresses_vec(struct mptcp_sock *msk, 598 struct mptcp_addr_info *addrs) 599 { 600 struct sock *sk = (struct sock *)msk; 601 struct mptcp_pm_addr_entry *entry; 602 struct mptcp_addr_info local; 603 struct pm_nl_pernet *pernet; 604 unsigned int subflows_max; 605 int i = 0; 606 607 pernet = net_generic(sock_net(sk), pm_nl_pernet_id); 608 subflows_max = mptcp_pm_get_subflows_max(msk); 609 610 rcu_read_lock(); 611 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 612 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_FULLMESH)) 613 continue; 614 615 if (entry->addr.family != sk->sk_family) { 616 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 617 if ((entry->addr.family == AF_INET && 618 !ipv6_addr_v4mapped(&sk->sk_v6_daddr)) || 619 (sk->sk_family == AF_INET && 620 !ipv6_addr_v4mapped(&entry->addr.addr6))) 621 #endif 622 continue; 623 } 624 625 if (msk->pm.subflows < subflows_max) { 626 msk->pm.subflows++; 627 addrs[i++] = entry->addr; 628 } 629 } 630 rcu_read_unlock(); 631 632 /* If the array is empty, fill in the single 633 * 'IPADDRANY' local address 634 */ 635 if (!i) { 636 memset(&local, 0, sizeof(local)); 637 local.family = msk->pm.remote.family; 638 639 msk->pm.subflows++; 640 addrs[i++] = local; 641 } 642 643 return i; 644 } 645 646 static void mptcp_pm_nl_add_addr_received(struct mptcp_sock *msk) 647 { 648 struct mptcp_addr_info addrs[MPTCP_PM_ADDR_MAX]; 649 struct sock *sk = (struct sock *)msk; 650 unsigned int add_addr_accept_max; 651 struct mptcp_addr_info remote; 652 unsigned int subflows_max; 653 int i, nr; 654 655 add_addr_accept_max = mptcp_pm_get_add_addr_accept_max(msk); 656 subflows_max = mptcp_pm_get_subflows_max(msk); 657 658 pr_debug("accepted %d:%d remote family %d", 659 msk->pm.add_addr_accepted, add_addr_accept_max, 660 msk->pm.remote.family); 661 662 if (lookup_subflow_by_daddr(&msk->conn_list, &msk->pm.remote)) 663 goto add_addr_echo; 664 665 /* connect to the specified remote address, using whatever 666 * local address the routing configuration will pick. 667 */ 668 remote = msk->pm.remote; 669 if (!remote.port) 670 remote.port = sk->sk_dport; 671 nr = fill_local_addresses_vec(msk, addrs); 672 673 msk->pm.add_addr_accepted++; 674 if (msk->pm.add_addr_accepted >= add_addr_accept_max || 675 msk->pm.subflows >= subflows_max) 676 WRITE_ONCE(msk->pm.accept_addr, false); 677 678 spin_unlock_bh(&msk->pm.lock); 679 for (i = 0; i < nr; i++) 680 __mptcp_subflow_connect(sk, &addrs[i], &remote); 681 spin_lock_bh(&msk->pm.lock); 682 683 add_addr_echo: 684 mptcp_pm_announce_addr(msk, &msk->pm.remote, true); 685 mptcp_pm_nl_addr_send_ack(msk); 686 } 687 688 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk) 689 { 690 struct mptcp_subflow_context *subflow; 691 692 msk_owned_by_me(msk); 693 lockdep_assert_held(&msk->pm.lock); 694 695 if (!mptcp_pm_should_add_signal(msk) && 696 !mptcp_pm_should_rm_signal(msk)) 697 return; 698 699 subflow = list_first_entry_or_null(&msk->conn_list, typeof(*subflow), node); 700 if (subflow) { 701 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 702 703 spin_unlock_bh(&msk->pm.lock); 704 pr_debug("send ack for %s", 705 mptcp_pm_should_add_signal(msk) ? "add_addr" : "rm_addr"); 706 707 mptcp_subflow_send_ack(ssk); 708 spin_lock_bh(&msk->pm.lock); 709 } 710 } 711 712 static int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk, 713 struct mptcp_addr_info *addr, 714 u8 bkup) 715 { 716 struct mptcp_subflow_context *subflow; 717 718 pr_debug("bkup=%d", bkup); 719 720 mptcp_for_each_subflow(msk, subflow) { 721 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 722 struct sock *sk = (struct sock *)msk; 723 struct mptcp_addr_info local; 724 725 local_address((struct sock_common *)ssk, &local); 726 if (!addresses_equal(&local, addr, addr->port)) 727 continue; 728 729 subflow->backup = bkup; 730 subflow->send_mp_prio = 1; 731 subflow->request_bkup = bkup; 732 __MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_MPPRIOTX); 733 734 spin_unlock_bh(&msk->pm.lock); 735 pr_debug("send ack for mp_prio"); 736 mptcp_subflow_send_ack(ssk); 737 spin_lock_bh(&msk->pm.lock); 738 739 return 0; 740 } 741 742 return -EINVAL; 743 } 744 745 static void mptcp_pm_nl_rm_addr_or_subflow(struct mptcp_sock *msk, 746 const struct mptcp_rm_list *rm_list, 747 enum linux_mptcp_mib_field rm_type) 748 { 749 struct mptcp_subflow_context *subflow, *tmp; 750 struct sock *sk = (struct sock *)msk; 751 u8 i; 752 753 pr_debug("%s rm_list_nr %d", 754 rm_type == MPTCP_MIB_RMADDR ? "address" : "subflow", rm_list->nr); 755 756 msk_owned_by_me(msk); 757 758 if (sk->sk_state == TCP_LISTEN) 759 return; 760 761 if (!rm_list->nr) 762 return; 763 764 if (list_empty(&msk->conn_list)) 765 return; 766 767 for (i = 0; i < rm_list->nr; i++) { 768 bool removed = false; 769 770 list_for_each_entry_safe(subflow, tmp, &msk->conn_list, node) { 771 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 772 int how = RCV_SHUTDOWN | SEND_SHUTDOWN; 773 u8 id = subflow->local_id; 774 775 if (rm_type == MPTCP_MIB_RMADDR) 776 id = subflow->remote_id; 777 778 if (rm_list->ids[i] != id) 779 continue; 780 781 pr_debug(" -> %s rm_list_ids[%d]=%u local_id=%u remote_id=%u", 782 rm_type == MPTCP_MIB_RMADDR ? "address" : "subflow", 783 i, rm_list->ids[i], subflow->local_id, subflow->remote_id); 784 spin_unlock_bh(&msk->pm.lock); 785 mptcp_subflow_shutdown(sk, ssk, how); 786 787 /* the following takes care of updating the subflows counter */ 788 mptcp_close_ssk(sk, ssk, subflow); 789 spin_lock_bh(&msk->pm.lock); 790 791 removed = true; 792 __MPTCP_INC_STATS(sock_net(sk), rm_type); 793 } 794 __set_bit(rm_list->ids[i], msk->pm.id_avail_bitmap); 795 if (!removed) 796 continue; 797 798 if (rm_type == MPTCP_MIB_RMADDR) { 799 msk->pm.add_addr_accepted--; 800 WRITE_ONCE(msk->pm.accept_addr, true); 801 } else if (rm_type == MPTCP_MIB_RMSUBFLOW) { 802 msk->pm.local_addr_used--; 803 } 804 } 805 } 806 807 static void mptcp_pm_nl_rm_addr_received(struct mptcp_sock *msk) 808 { 809 mptcp_pm_nl_rm_addr_or_subflow(msk, &msk->pm.rm_list_rx, MPTCP_MIB_RMADDR); 810 } 811 812 void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk, 813 const struct mptcp_rm_list *rm_list) 814 { 815 mptcp_pm_nl_rm_addr_or_subflow(msk, rm_list, MPTCP_MIB_RMSUBFLOW); 816 } 817 818 void mptcp_pm_nl_work(struct mptcp_sock *msk) 819 { 820 struct mptcp_pm_data *pm = &msk->pm; 821 822 msk_owned_by_me(msk); 823 824 if (!(pm->status & MPTCP_PM_WORK_MASK)) 825 return; 826 827 spin_lock_bh(&msk->pm.lock); 828 829 pr_debug("msk=%p status=%x", msk, pm->status); 830 if (pm->status & BIT(MPTCP_PM_ADD_ADDR_RECEIVED)) { 831 pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_RECEIVED); 832 mptcp_pm_nl_add_addr_received(msk); 833 } 834 if (pm->status & BIT(MPTCP_PM_ADD_ADDR_SEND_ACK)) { 835 pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_SEND_ACK); 836 mptcp_pm_nl_addr_send_ack(msk); 837 } 838 if (pm->status & BIT(MPTCP_PM_RM_ADDR_RECEIVED)) { 839 pm->status &= ~BIT(MPTCP_PM_RM_ADDR_RECEIVED); 840 mptcp_pm_nl_rm_addr_received(msk); 841 } 842 if (pm->status & BIT(MPTCP_PM_ESTABLISHED)) { 843 pm->status &= ~BIT(MPTCP_PM_ESTABLISHED); 844 mptcp_pm_nl_fully_established(msk); 845 } 846 if (pm->status & BIT(MPTCP_PM_SUBFLOW_ESTABLISHED)) { 847 pm->status &= ~BIT(MPTCP_PM_SUBFLOW_ESTABLISHED); 848 mptcp_pm_nl_subflow_established(msk); 849 } 850 851 spin_unlock_bh(&msk->pm.lock); 852 } 853 854 static bool address_use_port(struct mptcp_pm_addr_entry *entry) 855 { 856 return (entry->flags & 857 (MPTCP_PM_ADDR_FLAG_SIGNAL | MPTCP_PM_ADDR_FLAG_SUBFLOW)) == 858 MPTCP_PM_ADDR_FLAG_SIGNAL; 859 } 860 861 static int mptcp_pm_nl_append_new_local_addr(struct pm_nl_pernet *pernet, 862 struct mptcp_pm_addr_entry *entry) 863 { 864 struct mptcp_pm_addr_entry *cur; 865 unsigned int addr_max; 866 int ret = -EINVAL; 867 868 spin_lock_bh(&pernet->lock); 869 /* to keep the code simple, don't do IDR-like allocation for address ID, 870 * just bail when we exceed limits 871 */ 872 if (pernet->next_id == MPTCP_PM_MAX_ADDR_ID) 873 pernet->next_id = 1; 874 if (pernet->addrs >= MPTCP_PM_ADDR_MAX) 875 goto out; 876 if (test_bit(entry->addr.id, pernet->id_bitmap)) 877 goto out; 878 879 /* do not insert duplicate address, differentiate on port only 880 * singled addresses 881 */ 882 list_for_each_entry(cur, &pernet->local_addr_list, list) { 883 if (addresses_equal(&cur->addr, &entry->addr, 884 address_use_port(entry) && 885 address_use_port(cur))) 886 goto out; 887 } 888 889 if (!entry->addr.id) { 890 find_next: 891 entry->addr.id = find_next_zero_bit(pernet->id_bitmap, 892 MPTCP_PM_MAX_ADDR_ID + 1, 893 pernet->next_id); 894 if (!entry->addr.id && pernet->next_id != 1) { 895 pernet->next_id = 1; 896 goto find_next; 897 } 898 } 899 900 if (!entry->addr.id) 901 goto out; 902 903 __set_bit(entry->addr.id, pernet->id_bitmap); 904 if (entry->addr.id > pernet->next_id) 905 pernet->next_id = entry->addr.id; 906 907 if (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL) { 908 addr_max = pernet->add_addr_signal_max; 909 WRITE_ONCE(pernet->add_addr_signal_max, addr_max + 1); 910 } 911 if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) { 912 addr_max = pernet->local_addr_max; 913 WRITE_ONCE(pernet->local_addr_max, addr_max + 1); 914 } 915 916 pernet->addrs++; 917 list_add_tail_rcu(&entry->list, &pernet->local_addr_list); 918 ret = entry->addr.id; 919 920 out: 921 spin_unlock_bh(&pernet->lock); 922 return ret; 923 } 924 925 static int mptcp_pm_nl_create_listen_socket(struct sock *sk, 926 struct mptcp_pm_addr_entry *entry) 927 { 928 int addrlen = sizeof(struct sockaddr_in); 929 struct sockaddr_storage addr; 930 struct mptcp_sock *msk; 931 struct socket *ssock; 932 int backlog = 1024; 933 int err; 934 935 err = sock_create_kern(sock_net(sk), entry->addr.family, 936 SOCK_STREAM, IPPROTO_MPTCP, &entry->lsk); 937 if (err) 938 return err; 939 940 msk = mptcp_sk(entry->lsk->sk); 941 if (!msk) { 942 err = -EINVAL; 943 goto out; 944 } 945 946 ssock = __mptcp_nmpc_socket(msk); 947 if (!ssock) { 948 err = -EINVAL; 949 goto out; 950 } 951 952 mptcp_info2sockaddr(&entry->addr, &addr, entry->addr.family); 953 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 954 if (entry->addr.family == AF_INET6) 955 addrlen = sizeof(struct sockaddr_in6); 956 #endif 957 err = kernel_bind(ssock, (struct sockaddr *)&addr, addrlen); 958 if (err) { 959 pr_warn("kernel_bind error, err=%d", err); 960 goto out; 961 } 962 963 err = kernel_listen(ssock, backlog); 964 if (err) { 965 pr_warn("kernel_listen error, err=%d", err); 966 goto out; 967 } 968 969 return 0; 970 971 out: 972 sock_release(entry->lsk); 973 return err; 974 } 975 976 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct sock_common *skc) 977 { 978 struct mptcp_pm_addr_entry *entry; 979 struct mptcp_addr_info skc_local; 980 struct mptcp_addr_info msk_local; 981 struct pm_nl_pernet *pernet; 982 int ret = -1; 983 984 if (WARN_ON_ONCE(!msk)) 985 return -1; 986 987 /* The 0 ID mapping is defined by the first subflow, copied into the msk 988 * addr 989 */ 990 local_address((struct sock_common *)msk, &msk_local); 991 local_address((struct sock_common *)skc, &skc_local); 992 if (addresses_equal(&msk_local, &skc_local, false)) 993 return 0; 994 995 if (address_zero(&skc_local)) 996 return 0; 997 998 pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id); 999 1000 rcu_read_lock(); 1001 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 1002 if (addresses_equal(&entry->addr, &skc_local, entry->addr.port)) { 1003 ret = entry->addr.id; 1004 break; 1005 } 1006 } 1007 rcu_read_unlock(); 1008 if (ret >= 0) 1009 return ret; 1010 1011 /* address not found, add to local list */ 1012 entry = kmalloc(sizeof(*entry), GFP_ATOMIC); 1013 if (!entry) 1014 return -ENOMEM; 1015 1016 entry->addr = skc_local; 1017 entry->addr.id = 0; 1018 entry->addr.port = 0; 1019 entry->ifindex = 0; 1020 entry->flags = 0; 1021 entry->lsk = NULL; 1022 ret = mptcp_pm_nl_append_new_local_addr(pernet, entry); 1023 if (ret < 0) 1024 kfree(entry); 1025 1026 return ret; 1027 } 1028 1029 void mptcp_pm_nl_data_init(struct mptcp_sock *msk) 1030 { 1031 struct mptcp_pm_data *pm = &msk->pm; 1032 bool subflows; 1033 1034 subflows = !!mptcp_pm_get_subflows_max(msk); 1035 WRITE_ONCE(pm->work_pending, (!!mptcp_pm_get_local_addr_max(msk) && subflows) || 1036 !!mptcp_pm_get_add_addr_signal_max(msk)); 1037 WRITE_ONCE(pm->accept_addr, !!mptcp_pm_get_add_addr_accept_max(msk) && subflows); 1038 WRITE_ONCE(pm->accept_subflow, subflows); 1039 } 1040 1041 #define MPTCP_PM_CMD_GRP_OFFSET 0 1042 #define MPTCP_PM_EV_GRP_OFFSET 1 1043 1044 static const struct genl_multicast_group mptcp_pm_mcgrps[] = { 1045 [MPTCP_PM_CMD_GRP_OFFSET] = { .name = MPTCP_PM_CMD_GRP_NAME, }, 1046 [MPTCP_PM_EV_GRP_OFFSET] = { .name = MPTCP_PM_EV_GRP_NAME, 1047 .flags = GENL_UNS_ADMIN_PERM, 1048 }, 1049 }; 1050 1051 static const struct nla_policy 1052 mptcp_pm_addr_policy[MPTCP_PM_ADDR_ATTR_MAX + 1] = { 1053 [MPTCP_PM_ADDR_ATTR_FAMILY] = { .type = NLA_U16, }, 1054 [MPTCP_PM_ADDR_ATTR_ID] = { .type = NLA_U8, }, 1055 [MPTCP_PM_ADDR_ATTR_ADDR4] = { .type = NLA_U32, }, 1056 [MPTCP_PM_ADDR_ATTR_ADDR6] = 1057 NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)), 1058 [MPTCP_PM_ADDR_ATTR_PORT] = { .type = NLA_U16 }, 1059 [MPTCP_PM_ADDR_ATTR_FLAGS] = { .type = NLA_U32 }, 1060 [MPTCP_PM_ADDR_ATTR_IF_IDX] = { .type = NLA_S32 }, 1061 }; 1062 1063 static const struct nla_policy mptcp_pm_policy[MPTCP_PM_ATTR_MAX + 1] = { 1064 [MPTCP_PM_ATTR_ADDR] = 1065 NLA_POLICY_NESTED(mptcp_pm_addr_policy), 1066 [MPTCP_PM_ATTR_RCV_ADD_ADDRS] = { .type = NLA_U32, }, 1067 [MPTCP_PM_ATTR_SUBFLOWS] = { .type = NLA_U32, }, 1068 }; 1069 1070 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk) 1071 { 1072 struct mptcp_subflow_context *iter, *subflow = mptcp_subflow_ctx(ssk); 1073 struct sock *sk = (struct sock *)msk; 1074 unsigned int active_max_loss_cnt; 1075 struct net *net = sock_net(sk); 1076 unsigned int stale_loss_cnt; 1077 bool slow; 1078 1079 stale_loss_cnt = mptcp_stale_loss_cnt(net); 1080 if (subflow->stale || !stale_loss_cnt || subflow->stale_count <= stale_loss_cnt) 1081 return; 1082 1083 /* look for another available subflow not in loss state */ 1084 active_max_loss_cnt = max_t(int, stale_loss_cnt - 1, 1); 1085 mptcp_for_each_subflow(msk, iter) { 1086 if (iter != subflow && mptcp_subflow_active(iter) && 1087 iter->stale_count < active_max_loss_cnt) { 1088 /* we have some alternatives, try to mark this subflow as idle ...*/ 1089 slow = lock_sock_fast(ssk); 1090 if (!tcp_rtx_and_write_queues_empty(ssk)) { 1091 subflow->stale = 1; 1092 __mptcp_retransmit_pending_data(sk); 1093 MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_SUBFLOWSTALE); 1094 } 1095 unlock_sock_fast(ssk, slow); 1096 1097 /* always try to push the pending data regarless of re-injections: 1098 * we can possibly use backup subflows now, and subflow selection 1099 * is cheap under the msk socket lock 1100 */ 1101 __mptcp_push_pending(sk, 0); 1102 return; 1103 } 1104 } 1105 } 1106 1107 static int mptcp_pm_family_to_addr(int family) 1108 { 1109 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1110 if (family == AF_INET6) 1111 return MPTCP_PM_ADDR_ATTR_ADDR6; 1112 #endif 1113 return MPTCP_PM_ADDR_ATTR_ADDR4; 1114 } 1115 1116 static int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info, 1117 bool require_family, 1118 struct mptcp_pm_addr_entry *entry) 1119 { 1120 struct nlattr *tb[MPTCP_PM_ADDR_ATTR_MAX + 1]; 1121 int err, addr_addr; 1122 1123 if (!attr) { 1124 GENL_SET_ERR_MSG(info, "missing address info"); 1125 return -EINVAL; 1126 } 1127 1128 /* no validation needed - was already done via nested policy */ 1129 err = nla_parse_nested_deprecated(tb, MPTCP_PM_ADDR_ATTR_MAX, attr, 1130 mptcp_pm_addr_policy, info->extack); 1131 if (err) 1132 return err; 1133 1134 memset(entry, 0, sizeof(*entry)); 1135 if (!tb[MPTCP_PM_ADDR_ATTR_FAMILY]) { 1136 if (!require_family) 1137 goto skip_family; 1138 1139 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1140 "missing family"); 1141 return -EINVAL; 1142 } 1143 1144 entry->addr.family = nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_FAMILY]); 1145 if (entry->addr.family != AF_INET 1146 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1147 && entry->addr.family != AF_INET6 1148 #endif 1149 ) { 1150 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1151 "unknown address family"); 1152 return -EINVAL; 1153 } 1154 addr_addr = mptcp_pm_family_to_addr(entry->addr.family); 1155 if (!tb[addr_addr]) { 1156 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1157 "missing address data"); 1158 return -EINVAL; 1159 } 1160 1161 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1162 if (entry->addr.family == AF_INET6) 1163 entry->addr.addr6 = nla_get_in6_addr(tb[addr_addr]); 1164 else 1165 #endif 1166 entry->addr.addr.s_addr = nla_get_in_addr(tb[addr_addr]); 1167 1168 skip_family: 1169 if (tb[MPTCP_PM_ADDR_ATTR_IF_IDX]) { 1170 u32 val = nla_get_s32(tb[MPTCP_PM_ADDR_ATTR_IF_IDX]); 1171 1172 entry->ifindex = val; 1173 } 1174 1175 if (tb[MPTCP_PM_ADDR_ATTR_ID]) 1176 entry->addr.id = nla_get_u8(tb[MPTCP_PM_ADDR_ATTR_ID]); 1177 1178 if (tb[MPTCP_PM_ADDR_ATTR_FLAGS]) 1179 entry->flags = nla_get_u32(tb[MPTCP_PM_ADDR_ATTR_FLAGS]); 1180 1181 if (tb[MPTCP_PM_ADDR_ATTR_PORT]) { 1182 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) { 1183 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1184 "flags must have signal when using port"); 1185 return -EINVAL; 1186 } 1187 entry->addr.port = htons(nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_PORT])); 1188 } 1189 1190 return 0; 1191 } 1192 1193 static struct pm_nl_pernet *genl_info_pm_nl(struct genl_info *info) 1194 { 1195 return net_generic(genl_info_net(info), pm_nl_pernet_id); 1196 } 1197 1198 static int mptcp_nl_add_subflow_or_signal_addr(struct net *net) 1199 { 1200 struct mptcp_sock *msk; 1201 long s_slot = 0, s_num = 0; 1202 1203 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1204 struct sock *sk = (struct sock *)msk; 1205 1206 if (!READ_ONCE(msk->fully_established)) 1207 goto next; 1208 1209 lock_sock(sk); 1210 spin_lock_bh(&msk->pm.lock); 1211 mptcp_pm_create_subflow_or_signal_addr(msk); 1212 spin_unlock_bh(&msk->pm.lock); 1213 release_sock(sk); 1214 1215 next: 1216 sock_put(sk); 1217 cond_resched(); 1218 } 1219 1220 return 0; 1221 } 1222 1223 static int mptcp_nl_cmd_add_addr(struct sk_buff *skb, struct genl_info *info) 1224 { 1225 struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR]; 1226 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1227 struct mptcp_pm_addr_entry addr, *entry; 1228 int ret; 1229 1230 ret = mptcp_pm_parse_addr(attr, info, true, &addr); 1231 if (ret < 0) 1232 return ret; 1233 1234 entry = kmalloc(sizeof(*entry), GFP_KERNEL); 1235 if (!entry) { 1236 GENL_SET_ERR_MSG(info, "can't allocate addr"); 1237 return -ENOMEM; 1238 } 1239 1240 *entry = addr; 1241 if (entry->addr.port) { 1242 ret = mptcp_pm_nl_create_listen_socket(skb->sk, entry); 1243 if (ret) { 1244 GENL_SET_ERR_MSG(info, "create listen socket error"); 1245 kfree(entry); 1246 return ret; 1247 } 1248 } 1249 ret = mptcp_pm_nl_append_new_local_addr(pernet, entry); 1250 if (ret < 0) { 1251 GENL_SET_ERR_MSG(info, "too many addresses or duplicate one"); 1252 if (entry->lsk) 1253 sock_release(entry->lsk); 1254 kfree(entry); 1255 return ret; 1256 } 1257 1258 mptcp_nl_add_subflow_or_signal_addr(sock_net(skb->sk)); 1259 1260 return 0; 1261 } 1262 1263 int mptcp_pm_get_flags_and_ifindex_by_id(struct net *net, unsigned int id, 1264 u8 *flags, int *ifindex) 1265 { 1266 struct mptcp_pm_addr_entry *entry; 1267 1268 *flags = 0; 1269 *ifindex = 0; 1270 1271 if (id) { 1272 rcu_read_lock(); 1273 entry = __lookup_addr_by_id(net_generic(net, pm_nl_pernet_id), id); 1274 if (entry) { 1275 *flags = entry->flags; 1276 *ifindex = entry->ifindex; 1277 } 1278 rcu_read_unlock(); 1279 } 1280 1281 return 0; 1282 } 1283 1284 static bool remove_anno_list_by_saddr(struct mptcp_sock *msk, 1285 struct mptcp_addr_info *addr) 1286 { 1287 struct mptcp_pm_add_entry *entry; 1288 1289 entry = mptcp_pm_del_add_timer(msk, addr, false); 1290 if (entry) { 1291 list_del(&entry->list); 1292 kfree(entry); 1293 return true; 1294 } 1295 1296 return false; 1297 } 1298 1299 static bool mptcp_pm_remove_anno_addr(struct mptcp_sock *msk, 1300 struct mptcp_addr_info *addr, 1301 bool force) 1302 { 1303 struct mptcp_rm_list list = { .nr = 0 }; 1304 bool ret; 1305 1306 list.ids[list.nr++] = addr->id; 1307 1308 ret = remove_anno_list_by_saddr(msk, addr); 1309 if (ret || force) { 1310 spin_lock_bh(&msk->pm.lock); 1311 mptcp_pm_remove_addr(msk, &list); 1312 spin_unlock_bh(&msk->pm.lock); 1313 } 1314 return ret; 1315 } 1316 1317 static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net, 1318 struct mptcp_addr_info *addr) 1319 { 1320 struct mptcp_sock *msk; 1321 long s_slot = 0, s_num = 0; 1322 struct mptcp_rm_list list = { .nr = 0 }; 1323 1324 pr_debug("remove_id=%d", addr->id); 1325 1326 list.ids[list.nr++] = addr->id; 1327 1328 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1329 struct sock *sk = (struct sock *)msk; 1330 bool remove_subflow; 1331 1332 if (list_empty(&msk->conn_list)) { 1333 mptcp_pm_remove_anno_addr(msk, addr, false); 1334 goto next; 1335 } 1336 1337 lock_sock(sk); 1338 remove_subflow = lookup_subflow_by_saddr(&msk->conn_list, addr); 1339 mptcp_pm_remove_anno_addr(msk, addr, remove_subflow); 1340 if (remove_subflow) 1341 mptcp_pm_remove_subflow(msk, &list); 1342 release_sock(sk); 1343 1344 next: 1345 sock_put(sk); 1346 cond_resched(); 1347 } 1348 1349 return 0; 1350 } 1351 1352 /* caller must ensure the RCU grace period is already elapsed */ 1353 static void __mptcp_pm_release_addr_entry(struct mptcp_pm_addr_entry *entry) 1354 { 1355 if (entry->lsk) 1356 sock_release(entry->lsk); 1357 kfree(entry); 1358 } 1359 1360 static int mptcp_nl_remove_id_zero_address(struct net *net, 1361 struct mptcp_addr_info *addr) 1362 { 1363 struct mptcp_rm_list list = { .nr = 0 }; 1364 long s_slot = 0, s_num = 0; 1365 struct mptcp_sock *msk; 1366 1367 list.ids[list.nr++] = 0; 1368 1369 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1370 struct sock *sk = (struct sock *)msk; 1371 struct mptcp_addr_info msk_local; 1372 1373 if (list_empty(&msk->conn_list)) 1374 goto next; 1375 1376 local_address((struct sock_common *)msk, &msk_local); 1377 if (!addresses_equal(&msk_local, addr, addr->port)) 1378 goto next; 1379 1380 lock_sock(sk); 1381 spin_lock_bh(&msk->pm.lock); 1382 mptcp_pm_remove_addr(msk, &list); 1383 mptcp_pm_nl_rm_subflow_received(msk, &list); 1384 spin_unlock_bh(&msk->pm.lock); 1385 release_sock(sk); 1386 1387 next: 1388 sock_put(sk); 1389 cond_resched(); 1390 } 1391 1392 return 0; 1393 } 1394 1395 static int mptcp_nl_cmd_del_addr(struct sk_buff *skb, struct genl_info *info) 1396 { 1397 struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR]; 1398 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1399 struct mptcp_pm_addr_entry addr, *entry; 1400 unsigned int addr_max; 1401 int ret; 1402 1403 ret = mptcp_pm_parse_addr(attr, info, false, &addr); 1404 if (ret < 0) 1405 return ret; 1406 1407 /* the zero id address is special: the first address used by the msk 1408 * always gets such an id, so different subflows can have different zero 1409 * id addresses. Additionally zero id is not accounted for in id_bitmap. 1410 * Let's use an 'mptcp_rm_list' instead of the common remove code. 1411 */ 1412 if (addr.addr.id == 0) 1413 return mptcp_nl_remove_id_zero_address(sock_net(skb->sk), &addr.addr); 1414 1415 spin_lock_bh(&pernet->lock); 1416 entry = __lookup_addr_by_id(pernet, addr.addr.id); 1417 if (!entry) { 1418 GENL_SET_ERR_MSG(info, "address not found"); 1419 spin_unlock_bh(&pernet->lock); 1420 return -EINVAL; 1421 } 1422 if (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL) { 1423 addr_max = pernet->add_addr_signal_max; 1424 WRITE_ONCE(pernet->add_addr_signal_max, addr_max - 1); 1425 } 1426 if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) { 1427 addr_max = pernet->local_addr_max; 1428 WRITE_ONCE(pernet->local_addr_max, addr_max - 1); 1429 } 1430 1431 pernet->addrs--; 1432 list_del_rcu(&entry->list); 1433 __clear_bit(entry->addr.id, pernet->id_bitmap); 1434 spin_unlock_bh(&pernet->lock); 1435 1436 mptcp_nl_remove_subflow_and_signal_addr(sock_net(skb->sk), &entry->addr); 1437 synchronize_rcu(); 1438 __mptcp_pm_release_addr_entry(entry); 1439 1440 return ret; 1441 } 1442 1443 static void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk, 1444 struct list_head *rm_list) 1445 { 1446 struct mptcp_rm_list alist = { .nr = 0 }, slist = { .nr = 0 }; 1447 struct mptcp_pm_addr_entry *entry; 1448 1449 list_for_each_entry(entry, rm_list, list) { 1450 if (lookup_subflow_by_saddr(&msk->conn_list, &entry->addr) && 1451 alist.nr < MPTCP_RM_IDS_MAX && 1452 slist.nr < MPTCP_RM_IDS_MAX) { 1453 alist.ids[alist.nr++] = entry->addr.id; 1454 slist.ids[slist.nr++] = entry->addr.id; 1455 } else if (remove_anno_list_by_saddr(msk, &entry->addr) && 1456 alist.nr < MPTCP_RM_IDS_MAX) { 1457 alist.ids[alist.nr++] = entry->addr.id; 1458 } 1459 } 1460 1461 if (alist.nr) { 1462 spin_lock_bh(&msk->pm.lock); 1463 mptcp_pm_remove_addr(msk, &alist); 1464 spin_unlock_bh(&msk->pm.lock); 1465 } 1466 if (slist.nr) 1467 mptcp_pm_remove_subflow(msk, &slist); 1468 } 1469 1470 static void mptcp_nl_remove_addrs_list(struct net *net, 1471 struct list_head *rm_list) 1472 { 1473 long s_slot = 0, s_num = 0; 1474 struct mptcp_sock *msk; 1475 1476 if (list_empty(rm_list)) 1477 return; 1478 1479 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1480 struct sock *sk = (struct sock *)msk; 1481 1482 lock_sock(sk); 1483 mptcp_pm_remove_addrs_and_subflows(msk, rm_list); 1484 release_sock(sk); 1485 1486 sock_put(sk); 1487 cond_resched(); 1488 } 1489 } 1490 1491 /* caller must ensure the RCU grace period is already elapsed */ 1492 static void __flush_addrs(struct list_head *list) 1493 { 1494 while (!list_empty(list)) { 1495 struct mptcp_pm_addr_entry *cur; 1496 1497 cur = list_entry(list->next, 1498 struct mptcp_pm_addr_entry, list); 1499 list_del_rcu(&cur->list); 1500 __mptcp_pm_release_addr_entry(cur); 1501 } 1502 } 1503 1504 static void __reset_counters(struct pm_nl_pernet *pernet) 1505 { 1506 WRITE_ONCE(pernet->add_addr_signal_max, 0); 1507 WRITE_ONCE(pernet->add_addr_accept_max, 0); 1508 WRITE_ONCE(pernet->local_addr_max, 0); 1509 pernet->addrs = 0; 1510 } 1511 1512 static int mptcp_nl_cmd_flush_addrs(struct sk_buff *skb, struct genl_info *info) 1513 { 1514 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1515 LIST_HEAD(free_list); 1516 1517 spin_lock_bh(&pernet->lock); 1518 list_splice_init(&pernet->local_addr_list, &free_list); 1519 __reset_counters(pernet); 1520 pernet->next_id = 1; 1521 bitmap_zero(pernet->id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); 1522 spin_unlock_bh(&pernet->lock); 1523 mptcp_nl_remove_addrs_list(sock_net(skb->sk), &free_list); 1524 synchronize_rcu(); 1525 __flush_addrs(&free_list); 1526 return 0; 1527 } 1528 1529 static int mptcp_nl_fill_addr(struct sk_buff *skb, 1530 struct mptcp_pm_addr_entry *entry) 1531 { 1532 struct mptcp_addr_info *addr = &entry->addr; 1533 struct nlattr *attr; 1534 1535 attr = nla_nest_start(skb, MPTCP_PM_ATTR_ADDR); 1536 if (!attr) 1537 return -EMSGSIZE; 1538 1539 if (nla_put_u16(skb, MPTCP_PM_ADDR_ATTR_FAMILY, addr->family)) 1540 goto nla_put_failure; 1541 if (nla_put_u16(skb, MPTCP_PM_ADDR_ATTR_PORT, ntohs(addr->port))) 1542 goto nla_put_failure; 1543 if (nla_put_u8(skb, MPTCP_PM_ADDR_ATTR_ID, addr->id)) 1544 goto nla_put_failure; 1545 if (nla_put_u32(skb, MPTCP_PM_ADDR_ATTR_FLAGS, entry->flags)) 1546 goto nla_put_failure; 1547 if (entry->ifindex && 1548 nla_put_s32(skb, MPTCP_PM_ADDR_ATTR_IF_IDX, entry->ifindex)) 1549 goto nla_put_failure; 1550 1551 if (addr->family == AF_INET && 1552 nla_put_in_addr(skb, MPTCP_PM_ADDR_ATTR_ADDR4, 1553 addr->addr.s_addr)) 1554 goto nla_put_failure; 1555 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1556 else if (addr->family == AF_INET6 && 1557 nla_put_in6_addr(skb, MPTCP_PM_ADDR_ATTR_ADDR6, &addr->addr6)) 1558 goto nla_put_failure; 1559 #endif 1560 nla_nest_end(skb, attr); 1561 return 0; 1562 1563 nla_put_failure: 1564 nla_nest_cancel(skb, attr); 1565 return -EMSGSIZE; 1566 } 1567 1568 static int mptcp_nl_cmd_get_addr(struct sk_buff *skb, struct genl_info *info) 1569 { 1570 struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR]; 1571 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1572 struct mptcp_pm_addr_entry addr, *entry; 1573 struct sk_buff *msg; 1574 void *reply; 1575 int ret; 1576 1577 ret = mptcp_pm_parse_addr(attr, info, false, &addr); 1578 if (ret < 0) 1579 return ret; 1580 1581 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 1582 if (!msg) 1583 return -ENOMEM; 1584 1585 reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0, 1586 info->genlhdr->cmd); 1587 if (!reply) { 1588 GENL_SET_ERR_MSG(info, "not enough space in Netlink message"); 1589 ret = -EMSGSIZE; 1590 goto fail; 1591 } 1592 1593 spin_lock_bh(&pernet->lock); 1594 entry = __lookup_addr_by_id(pernet, addr.addr.id); 1595 if (!entry) { 1596 GENL_SET_ERR_MSG(info, "address not found"); 1597 ret = -EINVAL; 1598 goto unlock_fail; 1599 } 1600 1601 ret = mptcp_nl_fill_addr(msg, entry); 1602 if (ret) 1603 goto unlock_fail; 1604 1605 genlmsg_end(msg, reply); 1606 ret = genlmsg_reply(msg, info); 1607 spin_unlock_bh(&pernet->lock); 1608 return ret; 1609 1610 unlock_fail: 1611 spin_unlock_bh(&pernet->lock); 1612 1613 fail: 1614 nlmsg_free(msg); 1615 return ret; 1616 } 1617 1618 static int mptcp_nl_cmd_dump_addrs(struct sk_buff *msg, 1619 struct netlink_callback *cb) 1620 { 1621 struct net *net = sock_net(msg->sk); 1622 struct mptcp_pm_addr_entry *entry; 1623 struct pm_nl_pernet *pernet; 1624 int id = cb->args[0]; 1625 void *hdr; 1626 int i; 1627 1628 pernet = net_generic(net, pm_nl_pernet_id); 1629 1630 spin_lock_bh(&pernet->lock); 1631 for (i = id; i < MPTCP_PM_MAX_ADDR_ID + 1; i++) { 1632 if (test_bit(i, pernet->id_bitmap)) { 1633 entry = __lookup_addr_by_id(pernet, i); 1634 if (!entry) 1635 break; 1636 1637 if (entry->addr.id <= id) 1638 continue; 1639 1640 hdr = genlmsg_put(msg, NETLINK_CB(cb->skb).portid, 1641 cb->nlh->nlmsg_seq, &mptcp_genl_family, 1642 NLM_F_MULTI, MPTCP_PM_CMD_GET_ADDR); 1643 if (!hdr) 1644 break; 1645 1646 if (mptcp_nl_fill_addr(msg, entry) < 0) { 1647 genlmsg_cancel(msg, hdr); 1648 break; 1649 } 1650 1651 id = entry->addr.id; 1652 genlmsg_end(msg, hdr); 1653 } 1654 } 1655 spin_unlock_bh(&pernet->lock); 1656 1657 cb->args[0] = id; 1658 return msg->len; 1659 } 1660 1661 static int parse_limit(struct genl_info *info, int id, unsigned int *limit) 1662 { 1663 struct nlattr *attr = info->attrs[id]; 1664 1665 if (!attr) 1666 return 0; 1667 1668 *limit = nla_get_u32(attr); 1669 if (*limit > MPTCP_PM_ADDR_MAX) { 1670 GENL_SET_ERR_MSG(info, "limit greater than maximum"); 1671 return -EINVAL; 1672 } 1673 return 0; 1674 } 1675 1676 static int 1677 mptcp_nl_cmd_set_limits(struct sk_buff *skb, struct genl_info *info) 1678 { 1679 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1680 unsigned int rcv_addrs, subflows; 1681 int ret; 1682 1683 spin_lock_bh(&pernet->lock); 1684 rcv_addrs = pernet->add_addr_accept_max; 1685 ret = parse_limit(info, MPTCP_PM_ATTR_RCV_ADD_ADDRS, &rcv_addrs); 1686 if (ret) 1687 goto unlock; 1688 1689 subflows = pernet->subflows_max; 1690 ret = parse_limit(info, MPTCP_PM_ATTR_SUBFLOWS, &subflows); 1691 if (ret) 1692 goto unlock; 1693 1694 WRITE_ONCE(pernet->add_addr_accept_max, rcv_addrs); 1695 WRITE_ONCE(pernet->subflows_max, subflows); 1696 1697 unlock: 1698 spin_unlock_bh(&pernet->lock); 1699 return ret; 1700 } 1701 1702 static int 1703 mptcp_nl_cmd_get_limits(struct sk_buff *skb, struct genl_info *info) 1704 { 1705 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1706 struct sk_buff *msg; 1707 void *reply; 1708 1709 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 1710 if (!msg) 1711 return -ENOMEM; 1712 1713 reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0, 1714 MPTCP_PM_CMD_GET_LIMITS); 1715 if (!reply) 1716 goto fail; 1717 1718 if (nla_put_u32(msg, MPTCP_PM_ATTR_RCV_ADD_ADDRS, 1719 READ_ONCE(pernet->add_addr_accept_max))) 1720 goto fail; 1721 1722 if (nla_put_u32(msg, MPTCP_PM_ATTR_SUBFLOWS, 1723 READ_ONCE(pernet->subflows_max))) 1724 goto fail; 1725 1726 genlmsg_end(msg, reply); 1727 return genlmsg_reply(msg, info); 1728 1729 fail: 1730 GENL_SET_ERR_MSG(info, "not enough space in Netlink message"); 1731 nlmsg_free(msg); 1732 return -EMSGSIZE; 1733 } 1734 1735 static int mptcp_nl_addr_backup(struct net *net, 1736 struct mptcp_addr_info *addr, 1737 u8 bkup) 1738 { 1739 long s_slot = 0, s_num = 0; 1740 struct mptcp_sock *msk; 1741 int ret = -EINVAL; 1742 1743 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1744 struct sock *sk = (struct sock *)msk; 1745 1746 if (list_empty(&msk->conn_list)) 1747 goto next; 1748 1749 lock_sock(sk); 1750 spin_lock_bh(&msk->pm.lock); 1751 ret = mptcp_pm_nl_mp_prio_send_ack(msk, addr, bkup); 1752 spin_unlock_bh(&msk->pm.lock); 1753 release_sock(sk); 1754 1755 next: 1756 sock_put(sk); 1757 cond_resched(); 1758 } 1759 1760 return ret; 1761 } 1762 1763 static int mptcp_nl_cmd_set_flags(struct sk_buff *skb, struct genl_info *info) 1764 { 1765 struct mptcp_pm_addr_entry addr = { .addr = { .family = AF_UNSPEC }, }, *entry; 1766 struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR]; 1767 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1768 struct net *net = sock_net(skb->sk); 1769 u8 bkup = 0, lookup_by_id = 0; 1770 int ret; 1771 1772 ret = mptcp_pm_parse_addr(attr, info, false, &addr); 1773 if (ret < 0) 1774 return ret; 1775 1776 if (addr.flags & MPTCP_PM_ADDR_FLAG_BACKUP) 1777 bkup = 1; 1778 if (addr.addr.family == AF_UNSPEC) { 1779 lookup_by_id = 1; 1780 if (!addr.addr.id) 1781 return -EOPNOTSUPP; 1782 } 1783 1784 spin_lock_bh(&pernet->lock); 1785 entry = __lookup_addr(pernet, &addr.addr, lookup_by_id); 1786 if (!entry) { 1787 spin_unlock_bh(&pernet->lock); 1788 return -EINVAL; 1789 } 1790 1791 if (bkup) 1792 entry->flags |= MPTCP_PM_ADDR_FLAG_BACKUP; 1793 else 1794 entry->flags &= ~MPTCP_PM_ADDR_FLAG_BACKUP; 1795 addr = *entry; 1796 spin_unlock_bh(&pernet->lock); 1797 1798 mptcp_nl_addr_backup(net, &addr.addr, bkup); 1799 return 0; 1800 } 1801 1802 static void mptcp_nl_mcast_send(struct net *net, struct sk_buff *nlskb, gfp_t gfp) 1803 { 1804 genlmsg_multicast_netns(&mptcp_genl_family, net, 1805 nlskb, 0, MPTCP_PM_EV_GRP_OFFSET, gfp); 1806 } 1807 1808 static int mptcp_event_add_subflow(struct sk_buff *skb, const struct sock *ssk) 1809 { 1810 const struct inet_sock *issk = inet_sk(ssk); 1811 const struct mptcp_subflow_context *sf; 1812 1813 if (nla_put_u16(skb, MPTCP_ATTR_FAMILY, ssk->sk_family)) 1814 return -EMSGSIZE; 1815 1816 switch (ssk->sk_family) { 1817 case AF_INET: 1818 if (nla_put_in_addr(skb, MPTCP_ATTR_SADDR4, issk->inet_saddr)) 1819 return -EMSGSIZE; 1820 if (nla_put_in_addr(skb, MPTCP_ATTR_DADDR4, issk->inet_daddr)) 1821 return -EMSGSIZE; 1822 break; 1823 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1824 case AF_INET6: { 1825 const struct ipv6_pinfo *np = inet6_sk(ssk); 1826 1827 if (nla_put_in6_addr(skb, MPTCP_ATTR_SADDR6, &np->saddr)) 1828 return -EMSGSIZE; 1829 if (nla_put_in6_addr(skb, MPTCP_ATTR_DADDR6, &ssk->sk_v6_daddr)) 1830 return -EMSGSIZE; 1831 break; 1832 } 1833 #endif 1834 default: 1835 WARN_ON_ONCE(1); 1836 return -EMSGSIZE; 1837 } 1838 1839 if (nla_put_be16(skb, MPTCP_ATTR_SPORT, issk->inet_sport)) 1840 return -EMSGSIZE; 1841 if (nla_put_be16(skb, MPTCP_ATTR_DPORT, issk->inet_dport)) 1842 return -EMSGSIZE; 1843 1844 sf = mptcp_subflow_ctx(ssk); 1845 if (WARN_ON_ONCE(!sf)) 1846 return -EINVAL; 1847 1848 if (nla_put_u8(skb, MPTCP_ATTR_LOC_ID, sf->local_id)) 1849 return -EMSGSIZE; 1850 1851 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, sf->remote_id)) 1852 return -EMSGSIZE; 1853 1854 return 0; 1855 } 1856 1857 static int mptcp_event_put_token_and_ssk(struct sk_buff *skb, 1858 const struct mptcp_sock *msk, 1859 const struct sock *ssk) 1860 { 1861 const struct sock *sk = (const struct sock *)msk; 1862 const struct mptcp_subflow_context *sf; 1863 u8 sk_err; 1864 1865 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token)) 1866 return -EMSGSIZE; 1867 1868 if (mptcp_event_add_subflow(skb, ssk)) 1869 return -EMSGSIZE; 1870 1871 sf = mptcp_subflow_ctx(ssk); 1872 if (WARN_ON_ONCE(!sf)) 1873 return -EINVAL; 1874 1875 if (nla_put_u8(skb, MPTCP_ATTR_BACKUP, sf->backup)) 1876 return -EMSGSIZE; 1877 1878 if (ssk->sk_bound_dev_if && 1879 nla_put_s32(skb, MPTCP_ATTR_IF_IDX, ssk->sk_bound_dev_if)) 1880 return -EMSGSIZE; 1881 1882 sk_err = ssk->sk_err; 1883 if (sk_err && sk->sk_state == TCP_ESTABLISHED && 1884 nla_put_u8(skb, MPTCP_ATTR_ERROR, sk_err)) 1885 return -EMSGSIZE; 1886 1887 return 0; 1888 } 1889 1890 static int mptcp_event_sub_established(struct sk_buff *skb, 1891 const struct mptcp_sock *msk, 1892 const struct sock *ssk) 1893 { 1894 return mptcp_event_put_token_and_ssk(skb, msk, ssk); 1895 } 1896 1897 static int mptcp_event_sub_closed(struct sk_buff *skb, 1898 const struct mptcp_sock *msk, 1899 const struct sock *ssk) 1900 { 1901 const struct mptcp_subflow_context *sf; 1902 1903 if (mptcp_event_put_token_and_ssk(skb, msk, ssk)) 1904 return -EMSGSIZE; 1905 1906 sf = mptcp_subflow_ctx(ssk); 1907 if (!sf->reset_seen) 1908 return 0; 1909 1910 if (nla_put_u32(skb, MPTCP_ATTR_RESET_REASON, sf->reset_reason)) 1911 return -EMSGSIZE; 1912 1913 if (nla_put_u32(skb, MPTCP_ATTR_RESET_FLAGS, sf->reset_transient)) 1914 return -EMSGSIZE; 1915 1916 return 0; 1917 } 1918 1919 static int mptcp_event_created(struct sk_buff *skb, 1920 const struct mptcp_sock *msk, 1921 const struct sock *ssk) 1922 { 1923 int err = nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token); 1924 1925 if (err) 1926 return err; 1927 1928 return mptcp_event_add_subflow(skb, ssk); 1929 } 1930 1931 void mptcp_event_addr_removed(const struct mptcp_sock *msk, uint8_t id) 1932 { 1933 struct net *net = sock_net((const struct sock *)msk); 1934 struct nlmsghdr *nlh; 1935 struct sk_buff *skb; 1936 1937 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 1938 return; 1939 1940 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); 1941 if (!skb) 1942 return; 1943 1944 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, MPTCP_EVENT_REMOVED); 1945 if (!nlh) 1946 goto nla_put_failure; 1947 1948 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token)) 1949 goto nla_put_failure; 1950 1951 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, id)) 1952 goto nla_put_failure; 1953 1954 genlmsg_end(skb, nlh); 1955 mptcp_nl_mcast_send(net, skb, GFP_ATOMIC); 1956 return; 1957 1958 nla_put_failure: 1959 kfree_skb(skb); 1960 } 1961 1962 void mptcp_event_addr_announced(const struct mptcp_sock *msk, 1963 const struct mptcp_addr_info *info) 1964 { 1965 struct net *net = sock_net((const struct sock *)msk); 1966 struct nlmsghdr *nlh; 1967 struct sk_buff *skb; 1968 1969 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 1970 return; 1971 1972 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); 1973 if (!skb) 1974 return; 1975 1976 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, 1977 MPTCP_EVENT_ANNOUNCED); 1978 if (!nlh) 1979 goto nla_put_failure; 1980 1981 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token)) 1982 goto nla_put_failure; 1983 1984 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, info->id)) 1985 goto nla_put_failure; 1986 1987 if (nla_put_be16(skb, MPTCP_ATTR_DPORT, info->port)) 1988 goto nla_put_failure; 1989 1990 switch (info->family) { 1991 case AF_INET: 1992 if (nla_put_in_addr(skb, MPTCP_ATTR_DADDR4, info->addr.s_addr)) 1993 goto nla_put_failure; 1994 break; 1995 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1996 case AF_INET6: 1997 if (nla_put_in6_addr(skb, MPTCP_ATTR_DADDR6, &info->addr6)) 1998 goto nla_put_failure; 1999 break; 2000 #endif 2001 default: 2002 WARN_ON_ONCE(1); 2003 goto nla_put_failure; 2004 } 2005 2006 genlmsg_end(skb, nlh); 2007 mptcp_nl_mcast_send(net, skb, GFP_ATOMIC); 2008 return; 2009 2010 nla_put_failure: 2011 kfree_skb(skb); 2012 } 2013 2014 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk, 2015 const struct sock *ssk, gfp_t gfp) 2016 { 2017 struct net *net = sock_net((const struct sock *)msk); 2018 struct nlmsghdr *nlh; 2019 struct sk_buff *skb; 2020 2021 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2022 return; 2023 2024 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, gfp); 2025 if (!skb) 2026 return; 2027 2028 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, type); 2029 if (!nlh) 2030 goto nla_put_failure; 2031 2032 switch (type) { 2033 case MPTCP_EVENT_UNSPEC: 2034 WARN_ON_ONCE(1); 2035 break; 2036 case MPTCP_EVENT_CREATED: 2037 case MPTCP_EVENT_ESTABLISHED: 2038 if (mptcp_event_created(skb, msk, ssk) < 0) 2039 goto nla_put_failure; 2040 break; 2041 case MPTCP_EVENT_CLOSED: 2042 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token) < 0) 2043 goto nla_put_failure; 2044 break; 2045 case MPTCP_EVENT_ANNOUNCED: 2046 case MPTCP_EVENT_REMOVED: 2047 /* call mptcp_event_addr_announced()/removed instead */ 2048 WARN_ON_ONCE(1); 2049 break; 2050 case MPTCP_EVENT_SUB_ESTABLISHED: 2051 case MPTCP_EVENT_SUB_PRIORITY: 2052 if (mptcp_event_sub_established(skb, msk, ssk) < 0) 2053 goto nla_put_failure; 2054 break; 2055 case MPTCP_EVENT_SUB_CLOSED: 2056 if (mptcp_event_sub_closed(skb, msk, ssk) < 0) 2057 goto nla_put_failure; 2058 break; 2059 } 2060 2061 genlmsg_end(skb, nlh); 2062 mptcp_nl_mcast_send(net, skb, gfp); 2063 return; 2064 2065 nla_put_failure: 2066 kfree_skb(skb); 2067 } 2068 2069 static const struct genl_small_ops mptcp_pm_ops[] = { 2070 { 2071 .cmd = MPTCP_PM_CMD_ADD_ADDR, 2072 .doit = mptcp_nl_cmd_add_addr, 2073 .flags = GENL_ADMIN_PERM, 2074 }, 2075 { 2076 .cmd = MPTCP_PM_CMD_DEL_ADDR, 2077 .doit = mptcp_nl_cmd_del_addr, 2078 .flags = GENL_ADMIN_PERM, 2079 }, 2080 { 2081 .cmd = MPTCP_PM_CMD_FLUSH_ADDRS, 2082 .doit = mptcp_nl_cmd_flush_addrs, 2083 .flags = GENL_ADMIN_PERM, 2084 }, 2085 { 2086 .cmd = MPTCP_PM_CMD_GET_ADDR, 2087 .doit = mptcp_nl_cmd_get_addr, 2088 .dumpit = mptcp_nl_cmd_dump_addrs, 2089 }, 2090 { 2091 .cmd = MPTCP_PM_CMD_SET_LIMITS, 2092 .doit = mptcp_nl_cmd_set_limits, 2093 .flags = GENL_ADMIN_PERM, 2094 }, 2095 { 2096 .cmd = MPTCP_PM_CMD_GET_LIMITS, 2097 .doit = mptcp_nl_cmd_get_limits, 2098 }, 2099 { 2100 .cmd = MPTCP_PM_CMD_SET_FLAGS, 2101 .doit = mptcp_nl_cmd_set_flags, 2102 .flags = GENL_ADMIN_PERM, 2103 }, 2104 }; 2105 2106 static struct genl_family mptcp_genl_family __ro_after_init = { 2107 .name = MPTCP_PM_NAME, 2108 .version = MPTCP_PM_VER, 2109 .maxattr = MPTCP_PM_ATTR_MAX, 2110 .policy = mptcp_pm_policy, 2111 .netnsok = true, 2112 .module = THIS_MODULE, 2113 .small_ops = mptcp_pm_ops, 2114 .n_small_ops = ARRAY_SIZE(mptcp_pm_ops), 2115 .mcgrps = mptcp_pm_mcgrps, 2116 .n_mcgrps = ARRAY_SIZE(mptcp_pm_mcgrps), 2117 }; 2118 2119 static int __net_init pm_nl_init_net(struct net *net) 2120 { 2121 struct pm_nl_pernet *pernet = net_generic(net, pm_nl_pernet_id); 2122 2123 INIT_LIST_HEAD_RCU(&pernet->local_addr_list); 2124 2125 /* Cit. 2 subflows ought to be enough for anybody. */ 2126 pernet->subflows_max = 2; 2127 pernet->next_id = 1; 2128 pernet->stale_loss_cnt = 4; 2129 spin_lock_init(&pernet->lock); 2130 2131 /* No need to initialize other pernet fields, the struct is zeroed at 2132 * allocation time. 2133 */ 2134 2135 return 0; 2136 } 2137 2138 static void __net_exit pm_nl_exit_net(struct list_head *net_list) 2139 { 2140 struct net *net; 2141 2142 list_for_each_entry(net, net_list, exit_list) { 2143 struct pm_nl_pernet *pernet = net_generic(net, pm_nl_pernet_id); 2144 2145 /* net is removed from namespace list, can't race with 2146 * other modifiers, also netns core already waited for a 2147 * RCU grace period. 2148 */ 2149 __flush_addrs(&pernet->local_addr_list); 2150 } 2151 } 2152 2153 static struct pernet_operations mptcp_pm_pernet_ops = { 2154 .init = pm_nl_init_net, 2155 .exit_batch = pm_nl_exit_net, 2156 .id = &pm_nl_pernet_id, 2157 .size = sizeof(struct pm_nl_pernet), 2158 }; 2159 2160 void __init mptcp_pm_nl_init(void) 2161 { 2162 if (register_pernet_subsys(&mptcp_pm_pernet_ops) < 0) 2163 panic("Failed to register MPTCP PM pernet subsystem.\n"); 2164 2165 if (genl_register_family(&mptcp_genl_family)) 2166 panic("Failed to register MPTCP PM netlink family\n"); 2167 } 2168