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/inet_common.h> 13 #include <net/netns/generic.h> 14 #include <net/mptcp.h> 15 #include <net/genetlink.h> 16 #include <uapi/linux/mptcp.h> 17 18 #include "protocol.h" 19 #include "mib.h" 20 21 /* forward declaration */ 22 static struct genl_family mptcp_genl_family; 23 24 static int pm_nl_pernet_id; 25 26 struct mptcp_pm_add_entry { 27 struct list_head list; 28 struct mptcp_addr_info addr; 29 u8 retrans_times; 30 struct timer_list add_timer; 31 struct mptcp_sock *sock; 32 }; 33 34 struct pm_nl_pernet { 35 /* protects pernet updates */ 36 spinlock_t lock; 37 struct list_head local_addr_list; 38 unsigned int addrs; 39 unsigned int stale_loss_cnt; 40 unsigned int add_addr_signal_max; 41 unsigned int add_addr_accept_max; 42 unsigned int local_addr_max; 43 unsigned int subflows_max; 44 unsigned int next_id; 45 DECLARE_BITMAP(id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); 46 }; 47 48 #define MPTCP_PM_ADDR_MAX 8 49 #define ADD_ADDR_RETRANS_MAX 3 50 51 static struct pm_nl_pernet *pm_nl_get_pernet(const struct net *net) 52 { 53 return net_generic(net, pm_nl_pernet_id); 54 } 55 56 static struct pm_nl_pernet * 57 pm_nl_get_pernet_from_msk(const struct mptcp_sock *msk) 58 { 59 return pm_nl_get_pernet(sock_net((struct sock *)msk)); 60 } 61 62 bool mptcp_addresses_equal(const struct mptcp_addr_info *a, 63 const struct mptcp_addr_info *b, bool use_port) 64 { 65 bool addr_equals = false; 66 67 if (a->family == b->family) { 68 if (a->family == AF_INET) 69 addr_equals = a->addr.s_addr == b->addr.s_addr; 70 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 71 else 72 addr_equals = !ipv6_addr_cmp(&a->addr6, &b->addr6); 73 } else if (a->family == AF_INET) { 74 if (ipv6_addr_v4mapped(&b->addr6)) 75 addr_equals = a->addr.s_addr == b->addr6.s6_addr32[3]; 76 } else if (b->family == AF_INET) { 77 if (ipv6_addr_v4mapped(&a->addr6)) 78 addr_equals = a->addr6.s6_addr32[3] == b->addr.s_addr; 79 #endif 80 } 81 82 if (!addr_equals) 83 return false; 84 if (!use_port) 85 return true; 86 87 return a->port == b->port; 88 } 89 90 void mptcp_local_address(const struct sock_common *skc, struct mptcp_addr_info *addr) 91 { 92 addr->family = skc->skc_family; 93 addr->port = htons(skc->skc_num); 94 if (addr->family == AF_INET) 95 addr->addr.s_addr = skc->skc_rcv_saddr; 96 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 97 else if (addr->family == AF_INET6) 98 addr->addr6 = skc->skc_v6_rcv_saddr; 99 #endif 100 } 101 102 static void remote_address(const struct sock_common *skc, 103 struct mptcp_addr_info *addr) 104 { 105 addr->family = skc->skc_family; 106 addr->port = skc->skc_dport; 107 if (addr->family == AF_INET) 108 addr->addr.s_addr = skc->skc_daddr; 109 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 110 else if (addr->family == AF_INET6) 111 addr->addr6 = skc->skc_v6_daddr; 112 #endif 113 } 114 115 static bool lookup_subflow_by_saddr(const struct list_head *list, 116 const struct mptcp_addr_info *saddr) 117 { 118 struct mptcp_subflow_context *subflow; 119 struct mptcp_addr_info cur; 120 struct sock_common *skc; 121 122 list_for_each_entry(subflow, list, node) { 123 skc = (struct sock_common *)mptcp_subflow_tcp_sock(subflow); 124 125 mptcp_local_address(skc, &cur); 126 if (mptcp_addresses_equal(&cur, saddr, saddr->port)) 127 return true; 128 } 129 130 return false; 131 } 132 133 static bool lookup_subflow_by_daddr(const struct list_head *list, 134 const struct mptcp_addr_info *daddr) 135 { 136 struct mptcp_subflow_context *subflow; 137 struct mptcp_addr_info cur; 138 struct sock_common *skc; 139 140 list_for_each_entry(subflow, list, node) { 141 skc = (struct sock_common *)mptcp_subflow_tcp_sock(subflow); 142 143 remote_address(skc, &cur); 144 if (mptcp_addresses_equal(&cur, daddr, daddr->port)) 145 return true; 146 } 147 148 return false; 149 } 150 151 static struct mptcp_pm_addr_entry * 152 select_local_address(const struct pm_nl_pernet *pernet, 153 const struct mptcp_sock *msk) 154 { 155 struct mptcp_pm_addr_entry *entry, *ret = NULL; 156 157 msk_owned_by_me(msk); 158 159 rcu_read_lock(); 160 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 161 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW)) 162 continue; 163 164 if (!test_bit(entry->addr.id, msk->pm.id_avail_bitmap)) 165 continue; 166 167 ret = entry; 168 break; 169 } 170 rcu_read_unlock(); 171 return ret; 172 } 173 174 static struct mptcp_pm_addr_entry * 175 select_signal_address(struct pm_nl_pernet *pernet, const struct mptcp_sock *msk) 176 { 177 struct mptcp_pm_addr_entry *entry, *ret = NULL; 178 179 rcu_read_lock(); 180 /* do not keep any additional per socket state, just signal 181 * the address list in order. 182 * Note: removal from the local address list during the msk life-cycle 183 * can lead to additional addresses not being announced. 184 */ 185 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 186 if (!test_bit(entry->addr.id, msk->pm.id_avail_bitmap)) 187 continue; 188 189 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) 190 continue; 191 192 ret = entry; 193 break; 194 } 195 rcu_read_unlock(); 196 return ret; 197 } 198 199 unsigned int mptcp_pm_get_add_addr_signal_max(const struct mptcp_sock *msk) 200 { 201 const struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk); 202 203 return READ_ONCE(pernet->add_addr_signal_max); 204 } 205 EXPORT_SYMBOL_GPL(mptcp_pm_get_add_addr_signal_max); 206 207 unsigned int mptcp_pm_get_add_addr_accept_max(const struct mptcp_sock *msk) 208 { 209 struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk); 210 211 return READ_ONCE(pernet->add_addr_accept_max); 212 } 213 EXPORT_SYMBOL_GPL(mptcp_pm_get_add_addr_accept_max); 214 215 unsigned int mptcp_pm_get_subflows_max(const struct mptcp_sock *msk) 216 { 217 struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk); 218 219 return READ_ONCE(pernet->subflows_max); 220 } 221 EXPORT_SYMBOL_GPL(mptcp_pm_get_subflows_max); 222 223 unsigned int mptcp_pm_get_local_addr_max(const struct mptcp_sock *msk) 224 { 225 struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk); 226 227 return READ_ONCE(pernet->local_addr_max); 228 } 229 EXPORT_SYMBOL_GPL(mptcp_pm_get_local_addr_max); 230 231 bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk) 232 { 233 struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk); 234 235 if (msk->pm.subflows == mptcp_pm_get_subflows_max(msk) || 236 (find_next_and_bit(pernet->id_bitmap, msk->pm.id_avail_bitmap, 237 MPTCP_PM_MAX_ADDR_ID + 1, 0) == MPTCP_PM_MAX_ADDR_ID + 1)) { 238 WRITE_ONCE(msk->pm.work_pending, false); 239 return false; 240 } 241 return true; 242 } 243 244 struct mptcp_pm_add_entry * 245 mptcp_lookup_anno_list_by_saddr(const struct mptcp_sock *msk, 246 const struct mptcp_addr_info *addr) 247 { 248 struct mptcp_pm_add_entry *entry; 249 250 lockdep_assert_held(&msk->pm.lock); 251 252 list_for_each_entry(entry, &msk->pm.anno_list, list) { 253 if (mptcp_addresses_equal(&entry->addr, addr, true)) 254 return entry; 255 } 256 257 return NULL; 258 } 259 260 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk) 261 { 262 struct mptcp_pm_add_entry *entry; 263 struct mptcp_addr_info saddr; 264 bool ret = false; 265 266 mptcp_local_address((struct sock_common *)sk, &saddr); 267 268 spin_lock_bh(&msk->pm.lock); 269 list_for_each_entry(entry, &msk->pm.anno_list, list) { 270 if (mptcp_addresses_equal(&entry->addr, &saddr, true)) { 271 ret = true; 272 goto out; 273 } 274 } 275 276 out: 277 spin_unlock_bh(&msk->pm.lock); 278 return ret; 279 } 280 281 static void mptcp_pm_add_timer(struct timer_list *timer) 282 { 283 struct mptcp_pm_add_entry *entry = from_timer(entry, timer, add_timer); 284 struct mptcp_sock *msk = entry->sock; 285 struct sock *sk = (struct sock *)msk; 286 287 pr_debug("msk=%p", msk); 288 289 if (!msk) 290 return; 291 292 if (inet_sk_state_load(sk) == TCP_CLOSE) 293 return; 294 295 if (!entry->addr.id) 296 return; 297 298 if (mptcp_pm_should_add_signal_addr(msk)) { 299 sk_reset_timer(sk, timer, jiffies + TCP_RTO_MAX / 8); 300 goto out; 301 } 302 303 spin_lock_bh(&msk->pm.lock); 304 305 if (!mptcp_pm_should_add_signal_addr(msk)) { 306 pr_debug("retransmit ADD_ADDR id=%d", entry->addr.id); 307 mptcp_pm_announce_addr(msk, &entry->addr, false); 308 mptcp_pm_add_addr_send_ack(msk); 309 entry->retrans_times++; 310 } 311 312 if (entry->retrans_times < ADD_ADDR_RETRANS_MAX) 313 sk_reset_timer(sk, timer, 314 jiffies + mptcp_get_add_addr_timeout(sock_net(sk))); 315 316 spin_unlock_bh(&msk->pm.lock); 317 318 if (entry->retrans_times == ADD_ADDR_RETRANS_MAX) 319 mptcp_pm_subflow_established(msk); 320 321 out: 322 __sock_put(sk); 323 } 324 325 struct mptcp_pm_add_entry * 326 mptcp_pm_del_add_timer(struct mptcp_sock *msk, 327 const struct mptcp_addr_info *addr, bool check_id) 328 { 329 struct mptcp_pm_add_entry *entry; 330 struct sock *sk = (struct sock *)msk; 331 332 spin_lock_bh(&msk->pm.lock); 333 entry = mptcp_lookup_anno_list_by_saddr(msk, addr); 334 if (entry && (!check_id || entry->addr.id == addr->id)) 335 entry->retrans_times = ADD_ADDR_RETRANS_MAX; 336 spin_unlock_bh(&msk->pm.lock); 337 338 if (entry && (!check_id || entry->addr.id == addr->id)) 339 sk_stop_timer_sync(sk, &entry->add_timer); 340 341 return entry; 342 } 343 344 bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk, 345 const struct mptcp_addr_info *addr) 346 { 347 struct mptcp_pm_add_entry *add_entry = NULL; 348 struct sock *sk = (struct sock *)msk; 349 struct net *net = sock_net(sk); 350 351 lockdep_assert_held(&msk->pm.lock); 352 353 add_entry = mptcp_lookup_anno_list_by_saddr(msk, addr); 354 355 if (add_entry) { 356 if (mptcp_pm_is_kernel(msk)) 357 return false; 358 359 sk_reset_timer(sk, &add_entry->add_timer, 360 jiffies + mptcp_get_add_addr_timeout(net)); 361 return true; 362 } 363 364 add_entry = kmalloc(sizeof(*add_entry), GFP_ATOMIC); 365 if (!add_entry) 366 return false; 367 368 list_add(&add_entry->list, &msk->pm.anno_list); 369 370 add_entry->addr = *addr; 371 add_entry->sock = msk; 372 add_entry->retrans_times = 0; 373 374 timer_setup(&add_entry->add_timer, mptcp_pm_add_timer, 0); 375 sk_reset_timer(sk, &add_entry->add_timer, 376 jiffies + mptcp_get_add_addr_timeout(net)); 377 378 return true; 379 } 380 381 void mptcp_pm_free_anno_list(struct mptcp_sock *msk) 382 { 383 struct mptcp_pm_add_entry *entry, *tmp; 384 struct sock *sk = (struct sock *)msk; 385 LIST_HEAD(free_list); 386 387 pr_debug("msk=%p", msk); 388 389 spin_lock_bh(&msk->pm.lock); 390 list_splice_init(&msk->pm.anno_list, &free_list); 391 spin_unlock_bh(&msk->pm.lock); 392 393 list_for_each_entry_safe(entry, tmp, &free_list, list) { 394 sk_stop_timer_sync(sk, &entry->add_timer); 395 kfree(entry); 396 } 397 } 398 399 static bool lookup_address_in_vec(const struct mptcp_addr_info *addrs, unsigned int nr, 400 const struct mptcp_addr_info *addr) 401 { 402 int i; 403 404 for (i = 0; i < nr; i++) { 405 if (addrs[i].id == addr->id) 406 return true; 407 } 408 409 return false; 410 } 411 412 /* Fill all the remote addresses into the array addrs[], 413 * and return the array size. 414 */ 415 static unsigned int fill_remote_addresses_vec(struct mptcp_sock *msk, 416 struct mptcp_addr_info *local, 417 bool fullmesh, 418 struct mptcp_addr_info *addrs) 419 { 420 bool deny_id0 = READ_ONCE(msk->pm.remote_deny_join_id0); 421 struct sock *sk = (struct sock *)msk, *ssk; 422 struct mptcp_subflow_context *subflow; 423 struct mptcp_addr_info remote = { 0 }; 424 unsigned int subflows_max; 425 int i = 0; 426 427 subflows_max = mptcp_pm_get_subflows_max(msk); 428 remote_address((struct sock_common *)sk, &remote); 429 430 /* Non-fullmesh endpoint, fill in the single entry 431 * corresponding to the primary MPC subflow remote address 432 */ 433 if (!fullmesh) { 434 if (deny_id0) 435 return 0; 436 437 if (!mptcp_pm_addr_families_match(sk, local, &remote)) 438 return 0; 439 440 msk->pm.subflows++; 441 addrs[i++] = remote; 442 } else { 443 mptcp_for_each_subflow(msk, subflow) { 444 ssk = mptcp_subflow_tcp_sock(subflow); 445 remote_address((struct sock_common *)ssk, &addrs[i]); 446 addrs[i].id = subflow->remote_id; 447 if (deny_id0 && !addrs[i].id) 448 continue; 449 450 if (!mptcp_pm_addr_families_match(sk, local, &addrs[i])) 451 continue; 452 453 if (!lookup_address_in_vec(addrs, i, &addrs[i]) && 454 msk->pm.subflows < subflows_max) { 455 msk->pm.subflows++; 456 i++; 457 } 458 } 459 } 460 461 return i; 462 } 463 464 static void __mptcp_pm_send_ack(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow, 465 bool prio, bool backup) 466 { 467 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 468 bool slow; 469 470 pr_debug("send ack for %s", 471 prio ? "mp_prio" : (mptcp_pm_should_add_signal(msk) ? "add_addr" : "rm_addr")); 472 473 slow = lock_sock_fast(ssk); 474 if (prio) { 475 subflow->send_mp_prio = 1; 476 subflow->backup = backup; 477 subflow->request_bkup = backup; 478 } 479 480 __mptcp_subflow_send_ack(ssk); 481 unlock_sock_fast(ssk, slow); 482 } 483 484 static void mptcp_pm_send_ack(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow, 485 bool prio, bool backup) 486 { 487 spin_unlock_bh(&msk->pm.lock); 488 __mptcp_pm_send_ack(msk, subflow, prio, backup); 489 spin_lock_bh(&msk->pm.lock); 490 } 491 492 static struct mptcp_pm_addr_entry * 493 __lookup_addr_by_id(struct pm_nl_pernet *pernet, unsigned int id) 494 { 495 struct mptcp_pm_addr_entry *entry; 496 497 list_for_each_entry(entry, &pernet->local_addr_list, list) { 498 if (entry->addr.id == id) 499 return entry; 500 } 501 return NULL; 502 } 503 504 static struct mptcp_pm_addr_entry * 505 __lookup_addr(struct pm_nl_pernet *pernet, const struct mptcp_addr_info *info, 506 bool lookup_by_id) 507 { 508 struct mptcp_pm_addr_entry *entry; 509 510 list_for_each_entry(entry, &pernet->local_addr_list, list) { 511 if ((!lookup_by_id && 512 mptcp_addresses_equal(&entry->addr, info, entry->addr.port)) || 513 (lookup_by_id && entry->addr.id == info->id)) 514 return entry; 515 } 516 return NULL; 517 } 518 519 static void mptcp_pm_create_subflow_or_signal_addr(struct mptcp_sock *msk) 520 { 521 struct sock *sk = (struct sock *)msk; 522 struct mptcp_pm_addr_entry *local; 523 unsigned int add_addr_signal_max; 524 unsigned int local_addr_max; 525 struct pm_nl_pernet *pernet; 526 unsigned int subflows_max; 527 528 pernet = pm_nl_get_pernet(sock_net(sk)); 529 530 add_addr_signal_max = mptcp_pm_get_add_addr_signal_max(msk); 531 local_addr_max = mptcp_pm_get_local_addr_max(msk); 532 subflows_max = mptcp_pm_get_subflows_max(msk); 533 534 /* do lazy endpoint usage accounting for the MPC subflows */ 535 if (unlikely(!(msk->pm.status & BIT(MPTCP_PM_MPC_ENDPOINT_ACCOUNTED))) && msk->first) { 536 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(msk->first); 537 struct mptcp_pm_addr_entry *entry; 538 struct mptcp_addr_info mpc_addr; 539 bool backup = false; 540 541 mptcp_local_address((struct sock_common *)msk->first, &mpc_addr); 542 rcu_read_lock(); 543 entry = __lookup_addr(pernet, &mpc_addr, false); 544 if (entry) { 545 __clear_bit(entry->addr.id, msk->pm.id_avail_bitmap); 546 msk->mpc_endpoint_id = entry->addr.id; 547 backup = !!(entry->flags & MPTCP_PM_ADDR_FLAG_BACKUP); 548 } 549 rcu_read_unlock(); 550 551 if (backup) 552 mptcp_pm_send_ack(msk, subflow, true, backup); 553 554 msk->pm.status |= BIT(MPTCP_PM_MPC_ENDPOINT_ACCOUNTED); 555 } 556 557 pr_debug("local %d:%d signal %d:%d subflows %d:%d\n", 558 msk->pm.local_addr_used, local_addr_max, 559 msk->pm.add_addr_signaled, add_addr_signal_max, 560 msk->pm.subflows, subflows_max); 561 562 /* check first for announce */ 563 if (msk->pm.add_addr_signaled < add_addr_signal_max) { 564 local = select_signal_address(pernet, msk); 565 566 /* due to racing events on both ends we can reach here while 567 * previous add address is still running: if we invoke now 568 * mptcp_pm_announce_addr(), that will fail and the 569 * corresponding id will be marked as used. 570 * Instead let the PM machinery reschedule us when the 571 * current address announce will be completed. 572 */ 573 if (msk->pm.addr_signal & BIT(MPTCP_ADD_ADDR_SIGNAL)) 574 return; 575 576 if (local) { 577 if (mptcp_pm_alloc_anno_list(msk, &local->addr)) { 578 __clear_bit(local->addr.id, msk->pm.id_avail_bitmap); 579 msk->pm.add_addr_signaled++; 580 mptcp_pm_announce_addr(msk, &local->addr, false); 581 mptcp_pm_nl_addr_send_ack(msk); 582 } 583 } 584 } 585 586 /* check if should create a new subflow */ 587 while (msk->pm.local_addr_used < local_addr_max && 588 msk->pm.subflows < subflows_max) { 589 struct mptcp_addr_info addrs[MPTCP_PM_ADDR_MAX]; 590 bool fullmesh; 591 int i, nr; 592 593 local = select_local_address(pernet, msk); 594 if (!local) 595 break; 596 597 fullmesh = !!(local->flags & MPTCP_PM_ADDR_FLAG_FULLMESH); 598 599 msk->pm.local_addr_used++; 600 __clear_bit(local->addr.id, msk->pm.id_avail_bitmap); 601 nr = fill_remote_addresses_vec(msk, &local->addr, fullmesh, addrs); 602 if (nr == 0) 603 continue; 604 605 spin_unlock_bh(&msk->pm.lock); 606 for (i = 0; i < nr; i++) 607 __mptcp_subflow_connect(sk, &local->addr, &addrs[i]); 608 spin_lock_bh(&msk->pm.lock); 609 } 610 mptcp_pm_nl_check_work_pending(msk); 611 } 612 613 static void mptcp_pm_nl_fully_established(struct mptcp_sock *msk) 614 { 615 mptcp_pm_create_subflow_or_signal_addr(msk); 616 } 617 618 static void mptcp_pm_nl_subflow_established(struct mptcp_sock *msk) 619 { 620 mptcp_pm_create_subflow_or_signal_addr(msk); 621 } 622 623 /* Fill all the local addresses into the array addrs[], 624 * and return the array size. 625 */ 626 static unsigned int fill_local_addresses_vec(struct mptcp_sock *msk, 627 struct mptcp_addr_info *remote, 628 struct mptcp_addr_info *addrs) 629 { 630 struct sock *sk = (struct sock *)msk; 631 struct mptcp_pm_addr_entry *entry; 632 struct pm_nl_pernet *pernet; 633 unsigned int subflows_max; 634 int i = 0; 635 636 pernet = pm_nl_get_pernet_from_msk(msk); 637 subflows_max = mptcp_pm_get_subflows_max(msk); 638 639 rcu_read_lock(); 640 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 641 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_FULLMESH)) 642 continue; 643 644 if (!mptcp_pm_addr_families_match(sk, &entry->addr, remote)) 645 continue; 646 647 if (msk->pm.subflows < subflows_max) { 648 msk->pm.subflows++; 649 addrs[i++] = entry->addr; 650 } 651 } 652 rcu_read_unlock(); 653 654 /* If the array is empty, fill in the single 655 * 'IPADDRANY' local address 656 */ 657 if (!i) { 658 struct mptcp_addr_info local; 659 660 memset(&local, 0, sizeof(local)); 661 local.family = 662 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 663 remote->family == AF_INET6 && 664 ipv6_addr_v4mapped(&remote->addr6) ? AF_INET : 665 #endif 666 remote->family; 667 668 if (!mptcp_pm_addr_families_match(sk, &local, remote)) 669 return 0; 670 671 msk->pm.subflows++; 672 addrs[i++] = local; 673 } 674 675 return i; 676 } 677 678 static void mptcp_pm_nl_add_addr_received(struct mptcp_sock *msk) 679 { 680 struct mptcp_addr_info addrs[MPTCP_PM_ADDR_MAX]; 681 struct sock *sk = (struct sock *)msk; 682 unsigned int add_addr_accept_max; 683 struct mptcp_addr_info remote; 684 unsigned int subflows_max; 685 int i, nr; 686 687 add_addr_accept_max = mptcp_pm_get_add_addr_accept_max(msk); 688 subflows_max = mptcp_pm_get_subflows_max(msk); 689 690 pr_debug("accepted %d:%d remote family %d", 691 msk->pm.add_addr_accepted, add_addr_accept_max, 692 msk->pm.remote.family); 693 694 remote = msk->pm.remote; 695 mptcp_pm_announce_addr(msk, &remote, true); 696 mptcp_pm_nl_addr_send_ack(msk); 697 698 if (lookup_subflow_by_daddr(&msk->conn_list, &remote)) 699 return; 700 701 /* pick id 0 port, if none is provided the remote address */ 702 if (!remote.port) 703 remote.port = sk->sk_dport; 704 705 /* connect to the specified remote address, using whatever 706 * local address the routing configuration will pick. 707 */ 708 nr = fill_local_addresses_vec(msk, &remote, addrs); 709 if (nr == 0) 710 return; 711 712 msk->pm.add_addr_accepted++; 713 if (msk->pm.add_addr_accepted >= add_addr_accept_max || 714 msk->pm.subflows >= subflows_max) 715 WRITE_ONCE(msk->pm.accept_addr, false); 716 717 spin_unlock_bh(&msk->pm.lock); 718 for (i = 0; i < nr; i++) 719 __mptcp_subflow_connect(sk, &addrs[i], &remote); 720 spin_lock_bh(&msk->pm.lock); 721 } 722 723 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk) 724 { 725 struct mptcp_subflow_context *subflow; 726 727 msk_owned_by_me(msk); 728 lockdep_assert_held(&msk->pm.lock); 729 730 if (!mptcp_pm_should_add_signal(msk) && 731 !mptcp_pm_should_rm_signal(msk)) 732 return; 733 734 subflow = list_first_entry_or_null(&msk->conn_list, typeof(*subflow), node); 735 if (subflow) 736 mptcp_pm_send_ack(msk, subflow, false, false); 737 } 738 739 int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk, 740 struct mptcp_addr_info *addr, 741 struct mptcp_addr_info *rem, 742 u8 bkup) 743 { 744 struct mptcp_subflow_context *subflow; 745 746 pr_debug("bkup=%d", bkup); 747 748 mptcp_for_each_subflow(msk, subflow) { 749 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 750 struct mptcp_addr_info local, remote; 751 752 mptcp_local_address((struct sock_common *)ssk, &local); 753 if (!mptcp_addresses_equal(&local, addr, addr->port)) 754 continue; 755 756 if (rem && rem->family != AF_UNSPEC) { 757 remote_address((struct sock_common *)ssk, &remote); 758 if (!mptcp_addresses_equal(&remote, rem, rem->port)) 759 continue; 760 } 761 762 __mptcp_pm_send_ack(msk, subflow, true, bkup); 763 return 0; 764 } 765 766 return -EINVAL; 767 } 768 769 static bool mptcp_local_id_match(const struct mptcp_sock *msk, u8 local_id, u8 id) 770 { 771 return local_id == id || (!local_id && msk->mpc_endpoint_id == id); 772 } 773 774 static void mptcp_pm_nl_rm_addr_or_subflow(struct mptcp_sock *msk, 775 const struct mptcp_rm_list *rm_list, 776 enum linux_mptcp_mib_field rm_type) 777 { 778 struct mptcp_subflow_context *subflow, *tmp; 779 struct sock *sk = (struct sock *)msk; 780 u8 i; 781 782 pr_debug("%s rm_list_nr %d", 783 rm_type == MPTCP_MIB_RMADDR ? "address" : "subflow", rm_list->nr); 784 785 msk_owned_by_me(msk); 786 787 if (sk->sk_state == TCP_LISTEN) 788 return; 789 790 if (!rm_list->nr) 791 return; 792 793 if (list_empty(&msk->conn_list)) 794 return; 795 796 for (i = 0; i < rm_list->nr; i++) { 797 u8 rm_id = rm_list->ids[i]; 798 bool removed = false; 799 800 mptcp_for_each_subflow_safe(msk, subflow, tmp) { 801 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 802 int how = RCV_SHUTDOWN | SEND_SHUTDOWN; 803 u8 id = subflow->local_id; 804 805 if (rm_type == MPTCP_MIB_RMADDR && subflow->remote_id != rm_id) 806 continue; 807 if (rm_type == MPTCP_MIB_RMSUBFLOW && !mptcp_local_id_match(msk, id, rm_id)) 808 continue; 809 810 pr_debug(" -> %s rm_list_ids[%d]=%u local_id=%u remote_id=%u mpc_id=%u", 811 rm_type == MPTCP_MIB_RMADDR ? "address" : "subflow", 812 i, rm_id, subflow->local_id, subflow->remote_id, 813 msk->mpc_endpoint_id); 814 spin_unlock_bh(&msk->pm.lock); 815 mptcp_subflow_shutdown(sk, ssk, how); 816 817 /* the following takes care of updating the subflows counter */ 818 mptcp_close_ssk(sk, ssk, subflow); 819 spin_lock_bh(&msk->pm.lock); 820 821 removed = true; 822 __MPTCP_INC_STATS(sock_net(sk), rm_type); 823 } 824 if (rm_type == MPTCP_MIB_RMSUBFLOW) 825 __set_bit(rm_id ? rm_id : msk->mpc_endpoint_id, msk->pm.id_avail_bitmap); 826 if (!removed) 827 continue; 828 829 if (!mptcp_pm_is_kernel(msk)) 830 continue; 831 832 if (rm_type == MPTCP_MIB_RMADDR) { 833 msk->pm.add_addr_accepted--; 834 WRITE_ONCE(msk->pm.accept_addr, true); 835 } else if (rm_type == MPTCP_MIB_RMSUBFLOW) { 836 msk->pm.local_addr_used--; 837 } 838 } 839 } 840 841 static void mptcp_pm_nl_rm_addr_received(struct mptcp_sock *msk) 842 { 843 mptcp_pm_nl_rm_addr_or_subflow(msk, &msk->pm.rm_list_rx, MPTCP_MIB_RMADDR); 844 } 845 846 void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk, 847 const struct mptcp_rm_list *rm_list) 848 { 849 mptcp_pm_nl_rm_addr_or_subflow(msk, rm_list, MPTCP_MIB_RMSUBFLOW); 850 } 851 852 void mptcp_pm_nl_work(struct mptcp_sock *msk) 853 { 854 struct mptcp_pm_data *pm = &msk->pm; 855 856 msk_owned_by_me(msk); 857 858 if (!(pm->status & MPTCP_PM_WORK_MASK)) 859 return; 860 861 spin_lock_bh(&msk->pm.lock); 862 863 pr_debug("msk=%p status=%x", msk, pm->status); 864 if (pm->status & BIT(MPTCP_PM_ADD_ADDR_RECEIVED)) { 865 pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_RECEIVED); 866 mptcp_pm_nl_add_addr_received(msk); 867 } 868 if (pm->status & BIT(MPTCP_PM_ADD_ADDR_SEND_ACK)) { 869 pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_SEND_ACK); 870 mptcp_pm_nl_addr_send_ack(msk); 871 } 872 if (pm->status & BIT(MPTCP_PM_RM_ADDR_RECEIVED)) { 873 pm->status &= ~BIT(MPTCP_PM_RM_ADDR_RECEIVED); 874 mptcp_pm_nl_rm_addr_received(msk); 875 } 876 if (pm->status & BIT(MPTCP_PM_ESTABLISHED)) { 877 pm->status &= ~BIT(MPTCP_PM_ESTABLISHED); 878 mptcp_pm_nl_fully_established(msk); 879 } 880 if (pm->status & BIT(MPTCP_PM_SUBFLOW_ESTABLISHED)) { 881 pm->status &= ~BIT(MPTCP_PM_SUBFLOW_ESTABLISHED); 882 mptcp_pm_nl_subflow_established(msk); 883 } 884 885 spin_unlock_bh(&msk->pm.lock); 886 } 887 888 static bool address_use_port(struct mptcp_pm_addr_entry *entry) 889 { 890 return (entry->flags & 891 (MPTCP_PM_ADDR_FLAG_SIGNAL | MPTCP_PM_ADDR_FLAG_SUBFLOW)) == 892 MPTCP_PM_ADDR_FLAG_SIGNAL; 893 } 894 895 /* caller must ensure the RCU grace period is already elapsed */ 896 static void __mptcp_pm_release_addr_entry(struct mptcp_pm_addr_entry *entry) 897 { 898 if (entry->lsk) 899 sock_release(entry->lsk); 900 kfree(entry); 901 } 902 903 static int mptcp_pm_nl_append_new_local_addr(struct pm_nl_pernet *pernet, 904 struct mptcp_pm_addr_entry *entry) 905 { 906 struct mptcp_pm_addr_entry *cur, *del_entry = NULL; 907 unsigned int addr_max; 908 int ret = -EINVAL; 909 910 spin_lock_bh(&pernet->lock); 911 /* to keep the code simple, don't do IDR-like allocation for address ID, 912 * just bail when we exceed limits 913 */ 914 if (pernet->next_id == MPTCP_PM_MAX_ADDR_ID) 915 pernet->next_id = 1; 916 if (pernet->addrs >= MPTCP_PM_ADDR_MAX) { 917 ret = -ERANGE; 918 goto out; 919 } 920 if (test_bit(entry->addr.id, pernet->id_bitmap)) { 921 ret = -EBUSY; 922 goto out; 923 } 924 925 /* do not insert duplicate address, differentiate on port only 926 * singled addresses 927 */ 928 if (!address_use_port(entry)) 929 entry->addr.port = 0; 930 list_for_each_entry(cur, &pernet->local_addr_list, list) { 931 if (mptcp_addresses_equal(&cur->addr, &entry->addr, 932 cur->addr.port || entry->addr.port)) { 933 /* allow replacing the exiting endpoint only if such 934 * endpoint is an implicit one and the user-space 935 * did not provide an endpoint id 936 */ 937 if (!(cur->flags & MPTCP_PM_ADDR_FLAG_IMPLICIT)) { 938 ret = -EEXIST; 939 goto out; 940 } 941 if (entry->addr.id) 942 goto out; 943 944 pernet->addrs--; 945 entry->addr.id = cur->addr.id; 946 list_del_rcu(&cur->list); 947 del_entry = cur; 948 break; 949 } 950 } 951 952 if (!entry->addr.id) { 953 find_next: 954 entry->addr.id = find_next_zero_bit(pernet->id_bitmap, 955 MPTCP_PM_MAX_ADDR_ID + 1, 956 pernet->next_id); 957 if (!entry->addr.id && pernet->next_id != 1) { 958 pernet->next_id = 1; 959 goto find_next; 960 } 961 } 962 963 if (!entry->addr.id) 964 goto out; 965 966 __set_bit(entry->addr.id, pernet->id_bitmap); 967 if (entry->addr.id > pernet->next_id) 968 pernet->next_id = entry->addr.id; 969 970 if (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL) { 971 addr_max = pernet->add_addr_signal_max; 972 WRITE_ONCE(pernet->add_addr_signal_max, addr_max + 1); 973 } 974 if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) { 975 addr_max = pernet->local_addr_max; 976 WRITE_ONCE(pernet->local_addr_max, addr_max + 1); 977 } 978 979 pernet->addrs++; 980 if (!entry->addr.port) 981 list_add_tail_rcu(&entry->list, &pernet->local_addr_list); 982 else 983 list_add_rcu(&entry->list, &pernet->local_addr_list); 984 ret = entry->addr.id; 985 986 out: 987 spin_unlock_bh(&pernet->lock); 988 989 /* just replaced an existing entry, free it */ 990 if (del_entry) { 991 synchronize_rcu(); 992 __mptcp_pm_release_addr_entry(del_entry); 993 } 994 return ret; 995 } 996 997 static struct lock_class_key mptcp_slock_keys[2]; 998 static struct lock_class_key mptcp_keys[2]; 999 1000 static int mptcp_pm_nl_create_listen_socket(struct sock *sk, 1001 struct mptcp_pm_addr_entry *entry) 1002 { 1003 bool is_ipv6 = sk->sk_family == AF_INET6; 1004 int addrlen = sizeof(struct sockaddr_in); 1005 struct sockaddr_storage addr; 1006 struct sock *newsk, *ssk; 1007 int backlog = 1024; 1008 int err; 1009 1010 err = sock_create_kern(sock_net(sk), entry->addr.family, 1011 SOCK_STREAM, IPPROTO_MPTCP, &entry->lsk); 1012 if (err) 1013 return err; 1014 1015 newsk = entry->lsk->sk; 1016 if (!newsk) 1017 return -EINVAL; 1018 1019 /* The subflow socket lock is acquired in a nested to the msk one 1020 * in several places, even by the TCP stack, and this msk is a kernel 1021 * socket: lockdep complains. Instead of propagating the _nested 1022 * modifiers in several places, re-init the lock class for the msk 1023 * socket to an mptcp specific one. 1024 */ 1025 sock_lock_init_class_and_name(newsk, 1026 is_ipv6 ? "mlock-AF_INET6" : "mlock-AF_INET", 1027 &mptcp_slock_keys[is_ipv6], 1028 is_ipv6 ? "msk_lock-AF_INET6" : "msk_lock-AF_INET", 1029 &mptcp_keys[is_ipv6]); 1030 1031 lock_sock(newsk); 1032 ssk = __mptcp_nmpc_sk(mptcp_sk(newsk)); 1033 release_sock(newsk); 1034 if (IS_ERR(ssk)) 1035 return PTR_ERR(ssk); 1036 1037 mptcp_info2sockaddr(&entry->addr, &addr, entry->addr.family); 1038 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1039 if (entry->addr.family == AF_INET6) 1040 addrlen = sizeof(struct sockaddr_in6); 1041 #endif 1042 if (ssk->sk_family == AF_INET) 1043 err = inet_bind_sk(ssk, (struct sockaddr *)&addr, addrlen); 1044 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1045 else if (ssk->sk_family == AF_INET6) 1046 err = inet6_bind_sk(ssk, (struct sockaddr *)&addr, addrlen); 1047 #endif 1048 if (err) 1049 return err; 1050 1051 /* We don't use mptcp_set_state() here because it needs to be called 1052 * under the msk socket lock. For the moment, that will not bring 1053 * anything more than only calling inet_sk_state_store(), because the 1054 * old status is known (TCP_CLOSE). 1055 */ 1056 inet_sk_state_store(newsk, TCP_LISTEN); 1057 lock_sock(ssk); 1058 err = __inet_listen_sk(ssk, backlog); 1059 if (!err) 1060 mptcp_event_pm_listener(ssk, MPTCP_EVENT_LISTENER_CREATED); 1061 release_sock(ssk); 1062 return err; 1063 } 1064 1065 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc) 1066 { 1067 struct mptcp_pm_addr_entry *entry; 1068 struct pm_nl_pernet *pernet; 1069 int ret = -1; 1070 1071 pernet = pm_nl_get_pernet_from_msk(msk); 1072 1073 rcu_read_lock(); 1074 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 1075 if (mptcp_addresses_equal(&entry->addr, skc, entry->addr.port)) { 1076 ret = entry->addr.id; 1077 break; 1078 } 1079 } 1080 rcu_read_unlock(); 1081 if (ret >= 0) 1082 return ret; 1083 1084 /* address not found, add to local list */ 1085 entry = kmalloc(sizeof(*entry), GFP_ATOMIC); 1086 if (!entry) 1087 return -ENOMEM; 1088 1089 entry->addr = *skc; 1090 entry->addr.id = 0; 1091 entry->addr.port = 0; 1092 entry->ifindex = 0; 1093 entry->flags = MPTCP_PM_ADDR_FLAG_IMPLICIT; 1094 entry->lsk = NULL; 1095 ret = mptcp_pm_nl_append_new_local_addr(pernet, entry); 1096 if (ret < 0) 1097 kfree(entry); 1098 1099 return ret; 1100 } 1101 1102 #define MPTCP_PM_CMD_GRP_OFFSET 0 1103 #define MPTCP_PM_EV_GRP_OFFSET 1 1104 1105 static const struct genl_multicast_group mptcp_pm_mcgrps[] = { 1106 [MPTCP_PM_CMD_GRP_OFFSET] = { .name = MPTCP_PM_CMD_GRP_NAME, }, 1107 [MPTCP_PM_EV_GRP_OFFSET] = { .name = MPTCP_PM_EV_GRP_NAME, 1108 .flags = GENL_MCAST_CAP_NET_ADMIN, 1109 }, 1110 }; 1111 1112 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk) 1113 { 1114 struct mptcp_subflow_context *iter, *subflow = mptcp_subflow_ctx(ssk); 1115 struct sock *sk = (struct sock *)msk; 1116 unsigned int active_max_loss_cnt; 1117 struct net *net = sock_net(sk); 1118 unsigned int stale_loss_cnt; 1119 bool slow; 1120 1121 stale_loss_cnt = mptcp_stale_loss_cnt(net); 1122 if (subflow->stale || !stale_loss_cnt || subflow->stale_count <= stale_loss_cnt) 1123 return; 1124 1125 /* look for another available subflow not in loss state */ 1126 active_max_loss_cnt = max_t(int, stale_loss_cnt - 1, 1); 1127 mptcp_for_each_subflow(msk, iter) { 1128 if (iter != subflow && mptcp_subflow_active(iter) && 1129 iter->stale_count < active_max_loss_cnt) { 1130 /* we have some alternatives, try to mark this subflow as idle ...*/ 1131 slow = lock_sock_fast(ssk); 1132 if (!tcp_rtx_and_write_queues_empty(ssk)) { 1133 subflow->stale = 1; 1134 __mptcp_retransmit_pending_data(sk); 1135 MPTCP_INC_STATS(net, MPTCP_MIB_SUBFLOWSTALE); 1136 } 1137 unlock_sock_fast(ssk, slow); 1138 1139 /* always try to push the pending data regardless of re-injections: 1140 * we can possibly use backup subflows now, and subflow selection 1141 * is cheap under the msk socket lock 1142 */ 1143 __mptcp_push_pending(sk, 0); 1144 return; 1145 } 1146 } 1147 } 1148 1149 static int mptcp_pm_family_to_addr(int family) 1150 { 1151 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1152 if (family == AF_INET6) 1153 return MPTCP_PM_ADDR_ATTR_ADDR6; 1154 #endif 1155 return MPTCP_PM_ADDR_ATTR_ADDR4; 1156 } 1157 1158 static int mptcp_pm_parse_pm_addr_attr(struct nlattr *tb[], 1159 const struct nlattr *attr, 1160 struct genl_info *info, 1161 struct mptcp_addr_info *addr, 1162 bool require_family) 1163 { 1164 int err, addr_addr; 1165 1166 if (!attr) { 1167 GENL_SET_ERR_MSG(info, "missing address info"); 1168 return -EINVAL; 1169 } 1170 1171 /* no validation needed - was already done via nested policy */ 1172 err = nla_parse_nested_deprecated(tb, MPTCP_PM_ADDR_ATTR_MAX, attr, 1173 mptcp_pm_address_nl_policy, info->extack); 1174 if (err) 1175 return err; 1176 1177 if (tb[MPTCP_PM_ADDR_ATTR_ID]) 1178 addr->id = nla_get_u8(tb[MPTCP_PM_ADDR_ATTR_ID]); 1179 1180 if (!tb[MPTCP_PM_ADDR_ATTR_FAMILY]) { 1181 if (!require_family) 1182 return 0; 1183 1184 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1185 "missing family"); 1186 return -EINVAL; 1187 } 1188 1189 addr->family = nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_FAMILY]); 1190 if (addr->family != AF_INET 1191 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1192 && addr->family != AF_INET6 1193 #endif 1194 ) { 1195 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1196 "unknown address family"); 1197 return -EINVAL; 1198 } 1199 addr_addr = mptcp_pm_family_to_addr(addr->family); 1200 if (!tb[addr_addr]) { 1201 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1202 "missing address data"); 1203 return -EINVAL; 1204 } 1205 1206 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1207 if (addr->family == AF_INET6) 1208 addr->addr6 = nla_get_in6_addr(tb[addr_addr]); 1209 else 1210 #endif 1211 addr->addr.s_addr = nla_get_in_addr(tb[addr_addr]); 1212 1213 if (tb[MPTCP_PM_ADDR_ATTR_PORT]) 1214 addr->port = htons(nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_PORT])); 1215 1216 return 0; 1217 } 1218 1219 int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info, 1220 struct mptcp_addr_info *addr) 1221 { 1222 struct nlattr *tb[MPTCP_PM_ADDR_ATTR_MAX + 1]; 1223 1224 memset(addr, 0, sizeof(*addr)); 1225 1226 return mptcp_pm_parse_pm_addr_attr(tb, attr, info, addr, true); 1227 } 1228 1229 int mptcp_pm_parse_entry(struct nlattr *attr, struct genl_info *info, 1230 bool require_family, 1231 struct mptcp_pm_addr_entry *entry) 1232 { 1233 struct nlattr *tb[MPTCP_PM_ADDR_ATTR_MAX + 1]; 1234 int err; 1235 1236 memset(entry, 0, sizeof(*entry)); 1237 1238 err = mptcp_pm_parse_pm_addr_attr(tb, attr, info, &entry->addr, require_family); 1239 if (err) 1240 return err; 1241 1242 if (tb[MPTCP_PM_ADDR_ATTR_IF_IDX]) { 1243 u32 val = nla_get_s32(tb[MPTCP_PM_ADDR_ATTR_IF_IDX]); 1244 1245 entry->ifindex = val; 1246 } 1247 1248 if (tb[MPTCP_PM_ADDR_ATTR_FLAGS]) 1249 entry->flags = nla_get_u32(tb[MPTCP_PM_ADDR_ATTR_FLAGS]); 1250 1251 if (tb[MPTCP_PM_ADDR_ATTR_PORT]) 1252 entry->addr.port = htons(nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_PORT])); 1253 1254 return 0; 1255 } 1256 1257 static struct pm_nl_pernet *genl_info_pm_nl(struct genl_info *info) 1258 { 1259 return pm_nl_get_pernet(genl_info_net(info)); 1260 } 1261 1262 static int mptcp_nl_add_subflow_or_signal_addr(struct net *net) 1263 { 1264 struct mptcp_sock *msk; 1265 long s_slot = 0, s_num = 0; 1266 1267 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1268 struct sock *sk = (struct sock *)msk; 1269 1270 if (!READ_ONCE(msk->fully_established) || 1271 mptcp_pm_is_userspace(msk)) 1272 goto next; 1273 1274 lock_sock(sk); 1275 spin_lock_bh(&msk->pm.lock); 1276 mptcp_pm_create_subflow_or_signal_addr(msk); 1277 spin_unlock_bh(&msk->pm.lock); 1278 release_sock(sk); 1279 1280 next: 1281 sock_put(sk); 1282 cond_resched(); 1283 } 1284 1285 return 0; 1286 } 1287 1288 int mptcp_pm_nl_add_addr_doit(struct sk_buff *skb, struct genl_info *info) 1289 { 1290 struct nlattr *attr = info->attrs[MPTCP_PM_ENDPOINT_ADDR]; 1291 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1292 struct mptcp_pm_addr_entry addr, *entry; 1293 int ret; 1294 1295 ret = mptcp_pm_parse_entry(attr, info, true, &addr); 1296 if (ret < 0) 1297 return ret; 1298 1299 if (addr.addr.port && !(addr.flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) { 1300 GENL_SET_ERR_MSG(info, "flags must have signal when using port"); 1301 return -EINVAL; 1302 } 1303 1304 if (addr.flags & MPTCP_PM_ADDR_FLAG_SIGNAL && 1305 addr.flags & MPTCP_PM_ADDR_FLAG_FULLMESH) { 1306 GENL_SET_ERR_MSG(info, "flags mustn't have both signal and fullmesh"); 1307 return -EINVAL; 1308 } 1309 1310 if (addr.flags & MPTCP_PM_ADDR_FLAG_IMPLICIT) { 1311 GENL_SET_ERR_MSG(info, "can't create IMPLICIT endpoint"); 1312 return -EINVAL; 1313 } 1314 1315 entry = kzalloc(sizeof(*entry), GFP_KERNEL_ACCOUNT); 1316 if (!entry) { 1317 GENL_SET_ERR_MSG(info, "can't allocate addr"); 1318 return -ENOMEM; 1319 } 1320 1321 *entry = addr; 1322 if (entry->addr.port) { 1323 ret = mptcp_pm_nl_create_listen_socket(skb->sk, entry); 1324 if (ret) { 1325 GENL_SET_ERR_MSG_FMT(info, "create listen socket error: %d", ret); 1326 goto out_free; 1327 } 1328 } 1329 ret = mptcp_pm_nl_append_new_local_addr(pernet, entry); 1330 if (ret < 0) { 1331 GENL_SET_ERR_MSG_FMT(info, "too many addresses or duplicate one: %d", ret); 1332 goto out_free; 1333 } 1334 1335 mptcp_nl_add_subflow_or_signal_addr(sock_net(skb->sk)); 1336 return 0; 1337 1338 out_free: 1339 __mptcp_pm_release_addr_entry(entry); 1340 return ret; 1341 } 1342 1343 int mptcp_pm_nl_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, unsigned int id, 1344 u8 *flags, int *ifindex) 1345 { 1346 struct mptcp_pm_addr_entry *entry; 1347 struct sock *sk = (struct sock *)msk; 1348 struct net *net = sock_net(sk); 1349 1350 rcu_read_lock(); 1351 entry = __lookup_addr_by_id(pm_nl_get_pernet(net), id); 1352 if (entry) { 1353 *flags = entry->flags; 1354 *ifindex = entry->ifindex; 1355 } 1356 rcu_read_unlock(); 1357 1358 return 0; 1359 } 1360 1361 static bool remove_anno_list_by_saddr(struct mptcp_sock *msk, 1362 const struct mptcp_addr_info *addr) 1363 { 1364 struct mptcp_pm_add_entry *entry; 1365 1366 entry = mptcp_pm_del_add_timer(msk, addr, false); 1367 if (entry) { 1368 list_del(&entry->list); 1369 kfree(entry); 1370 return true; 1371 } 1372 1373 return false; 1374 } 1375 1376 static bool mptcp_pm_remove_anno_addr(struct mptcp_sock *msk, 1377 const struct mptcp_addr_info *addr, 1378 bool force) 1379 { 1380 struct mptcp_rm_list list = { .nr = 0 }; 1381 bool ret; 1382 1383 list.ids[list.nr++] = addr->id; 1384 1385 ret = remove_anno_list_by_saddr(msk, addr); 1386 if (ret || force) { 1387 spin_lock_bh(&msk->pm.lock); 1388 mptcp_pm_remove_addr(msk, &list); 1389 spin_unlock_bh(&msk->pm.lock); 1390 } 1391 return ret; 1392 } 1393 1394 static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net, 1395 const struct mptcp_pm_addr_entry *entry) 1396 { 1397 const struct mptcp_addr_info *addr = &entry->addr; 1398 struct mptcp_rm_list list = { .nr = 0 }; 1399 long s_slot = 0, s_num = 0; 1400 struct mptcp_sock *msk; 1401 1402 pr_debug("remove_id=%d", addr->id); 1403 1404 list.ids[list.nr++] = addr->id; 1405 1406 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1407 struct sock *sk = (struct sock *)msk; 1408 bool remove_subflow; 1409 1410 if (mptcp_pm_is_userspace(msk)) 1411 goto next; 1412 1413 if (list_empty(&msk->conn_list)) { 1414 mptcp_pm_remove_anno_addr(msk, addr, false); 1415 goto next; 1416 } 1417 1418 lock_sock(sk); 1419 remove_subflow = lookup_subflow_by_saddr(&msk->conn_list, addr); 1420 mptcp_pm_remove_anno_addr(msk, addr, remove_subflow && 1421 !(entry->flags & MPTCP_PM_ADDR_FLAG_IMPLICIT)); 1422 if (remove_subflow) 1423 mptcp_pm_remove_subflow(msk, &list); 1424 release_sock(sk); 1425 1426 next: 1427 sock_put(sk); 1428 cond_resched(); 1429 } 1430 1431 return 0; 1432 } 1433 1434 static int mptcp_nl_remove_id_zero_address(struct net *net, 1435 struct mptcp_addr_info *addr) 1436 { 1437 struct mptcp_rm_list list = { .nr = 0 }; 1438 long s_slot = 0, s_num = 0; 1439 struct mptcp_sock *msk; 1440 1441 list.ids[list.nr++] = 0; 1442 1443 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1444 struct sock *sk = (struct sock *)msk; 1445 struct mptcp_addr_info msk_local; 1446 1447 if (list_empty(&msk->conn_list) || mptcp_pm_is_userspace(msk)) 1448 goto next; 1449 1450 mptcp_local_address((struct sock_common *)msk, &msk_local); 1451 if (!mptcp_addresses_equal(&msk_local, addr, addr->port)) 1452 goto next; 1453 1454 lock_sock(sk); 1455 spin_lock_bh(&msk->pm.lock); 1456 mptcp_pm_remove_addr(msk, &list); 1457 mptcp_pm_nl_rm_subflow_received(msk, &list); 1458 spin_unlock_bh(&msk->pm.lock); 1459 release_sock(sk); 1460 1461 next: 1462 sock_put(sk); 1463 cond_resched(); 1464 } 1465 1466 return 0; 1467 } 1468 1469 int mptcp_pm_nl_del_addr_doit(struct sk_buff *skb, struct genl_info *info) 1470 { 1471 struct nlattr *attr = info->attrs[MPTCP_PM_ENDPOINT_ADDR]; 1472 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1473 struct mptcp_pm_addr_entry addr, *entry; 1474 unsigned int addr_max; 1475 int ret; 1476 1477 ret = mptcp_pm_parse_entry(attr, info, false, &addr); 1478 if (ret < 0) 1479 return ret; 1480 1481 /* the zero id address is special: the first address used by the msk 1482 * always gets such an id, so different subflows can have different zero 1483 * id addresses. Additionally zero id is not accounted for in id_bitmap. 1484 * Let's use an 'mptcp_rm_list' instead of the common remove code. 1485 */ 1486 if (addr.addr.id == 0) 1487 return mptcp_nl_remove_id_zero_address(sock_net(skb->sk), &addr.addr); 1488 1489 spin_lock_bh(&pernet->lock); 1490 entry = __lookup_addr_by_id(pernet, addr.addr.id); 1491 if (!entry) { 1492 GENL_SET_ERR_MSG(info, "address not found"); 1493 spin_unlock_bh(&pernet->lock); 1494 return -EINVAL; 1495 } 1496 if (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL) { 1497 addr_max = pernet->add_addr_signal_max; 1498 WRITE_ONCE(pernet->add_addr_signal_max, addr_max - 1); 1499 } 1500 if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) { 1501 addr_max = pernet->local_addr_max; 1502 WRITE_ONCE(pernet->local_addr_max, addr_max - 1); 1503 } 1504 1505 pernet->addrs--; 1506 list_del_rcu(&entry->list); 1507 __clear_bit(entry->addr.id, pernet->id_bitmap); 1508 spin_unlock_bh(&pernet->lock); 1509 1510 mptcp_nl_remove_subflow_and_signal_addr(sock_net(skb->sk), entry); 1511 synchronize_rcu(); 1512 __mptcp_pm_release_addr_entry(entry); 1513 1514 return ret; 1515 } 1516 1517 void mptcp_pm_remove_addrs(struct mptcp_sock *msk, struct list_head *rm_list) 1518 { 1519 struct mptcp_rm_list alist = { .nr = 0 }; 1520 struct mptcp_pm_addr_entry *entry; 1521 1522 list_for_each_entry(entry, rm_list, list) { 1523 if ((remove_anno_list_by_saddr(msk, &entry->addr) || 1524 lookup_subflow_by_saddr(&msk->conn_list, &entry->addr)) && 1525 alist.nr < MPTCP_RM_IDS_MAX) 1526 alist.ids[alist.nr++] = entry->addr.id; 1527 } 1528 1529 if (alist.nr) { 1530 spin_lock_bh(&msk->pm.lock); 1531 mptcp_pm_remove_addr(msk, &alist); 1532 spin_unlock_bh(&msk->pm.lock); 1533 } 1534 } 1535 1536 void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk, 1537 struct list_head *rm_list) 1538 { 1539 struct mptcp_rm_list alist = { .nr = 0 }, slist = { .nr = 0 }; 1540 struct mptcp_pm_addr_entry *entry; 1541 1542 list_for_each_entry(entry, rm_list, list) { 1543 if (lookup_subflow_by_saddr(&msk->conn_list, &entry->addr) && 1544 slist.nr < MPTCP_RM_IDS_MAX) 1545 slist.ids[slist.nr++] = entry->addr.id; 1546 1547 if (remove_anno_list_by_saddr(msk, &entry->addr) && 1548 alist.nr < MPTCP_RM_IDS_MAX) 1549 alist.ids[alist.nr++] = entry->addr.id; 1550 } 1551 1552 if (alist.nr) { 1553 spin_lock_bh(&msk->pm.lock); 1554 mptcp_pm_remove_addr(msk, &alist); 1555 spin_unlock_bh(&msk->pm.lock); 1556 } 1557 if (slist.nr) 1558 mptcp_pm_remove_subflow(msk, &slist); 1559 } 1560 1561 static void mptcp_nl_remove_addrs_list(struct net *net, 1562 struct list_head *rm_list) 1563 { 1564 long s_slot = 0, s_num = 0; 1565 struct mptcp_sock *msk; 1566 1567 if (list_empty(rm_list)) 1568 return; 1569 1570 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1571 struct sock *sk = (struct sock *)msk; 1572 1573 if (!mptcp_pm_is_userspace(msk)) { 1574 lock_sock(sk); 1575 mptcp_pm_remove_addrs_and_subflows(msk, rm_list); 1576 release_sock(sk); 1577 } 1578 1579 sock_put(sk); 1580 cond_resched(); 1581 } 1582 } 1583 1584 /* caller must ensure the RCU grace period is already elapsed */ 1585 static void __flush_addrs(struct list_head *list) 1586 { 1587 while (!list_empty(list)) { 1588 struct mptcp_pm_addr_entry *cur; 1589 1590 cur = list_entry(list->next, 1591 struct mptcp_pm_addr_entry, list); 1592 list_del_rcu(&cur->list); 1593 __mptcp_pm_release_addr_entry(cur); 1594 } 1595 } 1596 1597 static void __reset_counters(struct pm_nl_pernet *pernet) 1598 { 1599 WRITE_ONCE(pernet->add_addr_signal_max, 0); 1600 WRITE_ONCE(pernet->add_addr_accept_max, 0); 1601 WRITE_ONCE(pernet->local_addr_max, 0); 1602 pernet->addrs = 0; 1603 } 1604 1605 int mptcp_pm_nl_flush_addrs_doit(struct sk_buff *skb, struct genl_info *info) 1606 { 1607 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1608 LIST_HEAD(free_list); 1609 1610 spin_lock_bh(&pernet->lock); 1611 list_splice_init(&pernet->local_addr_list, &free_list); 1612 __reset_counters(pernet); 1613 pernet->next_id = 1; 1614 bitmap_zero(pernet->id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); 1615 spin_unlock_bh(&pernet->lock); 1616 mptcp_nl_remove_addrs_list(sock_net(skb->sk), &free_list); 1617 synchronize_rcu(); 1618 __flush_addrs(&free_list); 1619 return 0; 1620 } 1621 1622 static int mptcp_nl_fill_addr(struct sk_buff *skb, 1623 struct mptcp_pm_addr_entry *entry) 1624 { 1625 struct mptcp_addr_info *addr = &entry->addr; 1626 struct nlattr *attr; 1627 1628 attr = nla_nest_start(skb, MPTCP_PM_ATTR_ADDR); 1629 if (!attr) 1630 return -EMSGSIZE; 1631 1632 if (nla_put_u16(skb, MPTCP_PM_ADDR_ATTR_FAMILY, addr->family)) 1633 goto nla_put_failure; 1634 if (nla_put_u16(skb, MPTCP_PM_ADDR_ATTR_PORT, ntohs(addr->port))) 1635 goto nla_put_failure; 1636 if (nla_put_u8(skb, MPTCP_PM_ADDR_ATTR_ID, addr->id)) 1637 goto nla_put_failure; 1638 if (nla_put_u32(skb, MPTCP_PM_ADDR_ATTR_FLAGS, entry->flags)) 1639 goto nla_put_failure; 1640 if (entry->ifindex && 1641 nla_put_s32(skb, MPTCP_PM_ADDR_ATTR_IF_IDX, entry->ifindex)) 1642 goto nla_put_failure; 1643 1644 if (addr->family == AF_INET && 1645 nla_put_in_addr(skb, MPTCP_PM_ADDR_ATTR_ADDR4, 1646 addr->addr.s_addr)) 1647 goto nla_put_failure; 1648 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1649 else if (addr->family == AF_INET6 && 1650 nla_put_in6_addr(skb, MPTCP_PM_ADDR_ATTR_ADDR6, &addr->addr6)) 1651 goto nla_put_failure; 1652 #endif 1653 nla_nest_end(skb, attr); 1654 return 0; 1655 1656 nla_put_failure: 1657 nla_nest_cancel(skb, attr); 1658 return -EMSGSIZE; 1659 } 1660 1661 int mptcp_pm_nl_get_addr_doit(struct sk_buff *skb, struct genl_info *info) 1662 { 1663 struct nlattr *attr = info->attrs[MPTCP_PM_ENDPOINT_ADDR]; 1664 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1665 struct mptcp_pm_addr_entry addr, *entry; 1666 struct sk_buff *msg; 1667 void *reply; 1668 int ret; 1669 1670 ret = mptcp_pm_parse_entry(attr, info, false, &addr); 1671 if (ret < 0) 1672 return ret; 1673 1674 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 1675 if (!msg) 1676 return -ENOMEM; 1677 1678 reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0, 1679 info->genlhdr->cmd); 1680 if (!reply) { 1681 GENL_SET_ERR_MSG(info, "not enough space in Netlink message"); 1682 ret = -EMSGSIZE; 1683 goto fail; 1684 } 1685 1686 spin_lock_bh(&pernet->lock); 1687 entry = __lookup_addr_by_id(pernet, addr.addr.id); 1688 if (!entry) { 1689 GENL_SET_ERR_MSG(info, "address not found"); 1690 ret = -EINVAL; 1691 goto unlock_fail; 1692 } 1693 1694 ret = mptcp_nl_fill_addr(msg, entry); 1695 if (ret) 1696 goto unlock_fail; 1697 1698 genlmsg_end(msg, reply); 1699 ret = genlmsg_reply(msg, info); 1700 spin_unlock_bh(&pernet->lock); 1701 return ret; 1702 1703 unlock_fail: 1704 spin_unlock_bh(&pernet->lock); 1705 1706 fail: 1707 nlmsg_free(msg); 1708 return ret; 1709 } 1710 1711 int mptcp_pm_nl_get_addr_dumpit(struct sk_buff *msg, 1712 struct netlink_callback *cb) 1713 { 1714 struct net *net = sock_net(msg->sk); 1715 struct mptcp_pm_addr_entry *entry; 1716 struct pm_nl_pernet *pernet; 1717 int id = cb->args[0]; 1718 void *hdr; 1719 int i; 1720 1721 pernet = pm_nl_get_pernet(net); 1722 1723 spin_lock_bh(&pernet->lock); 1724 for (i = id; i < MPTCP_PM_MAX_ADDR_ID + 1; i++) { 1725 if (test_bit(i, pernet->id_bitmap)) { 1726 entry = __lookup_addr_by_id(pernet, i); 1727 if (!entry) 1728 break; 1729 1730 if (entry->addr.id <= id) 1731 continue; 1732 1733 hdr = genlmsg_put(msg, NETLINK_CB(cb->skb).portid, 1734 cb->nlh->nlmsg_seq, &mptcp_genl_family, 1735 NLM_F_MULTI, MPTCP_PM_CMD_GET_ADDR); 1736 if (!hdr) 1737 break; 1738 1739 if (mptcp_nl_fill_addr(msg, entry) < 0) { 1740 genlmsg_cancel(msg, hdr); 1741 break; 1742 } 1743 1744 id = entry->addr.id; 1745 genlmsg_end(msg, hdr); 1746 } 1747 } 1748 spin_unlock_bh(&pernet->lock); 1749 1750 cb->args[0] = id; 1751 return msg->len; 1752 } 1753 1754 static int parse_limit(struct genl_info *info, int id, unsigned int *limit) 1755 { 1756 struct nlattr *attr = info->attrs[id]; 1757 1758 if (!attr) 1759 return 0; 1760 1761 *limit = nla_get_u32(attr); 1762 if (*limit > MPTCP_PM_ADDR_MAX) { 1763 GENL_SET_ERR_MSG(info, "limit greater than maximum"); 1764 return -EINVAL; 1765 } 1766 return 0; 1767 } 1768 1769 int mptcp_pm_nl_set_limits_doit(struct sk_buff *skb, struct genl_info *info) 1770 { 1771 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1772 unsigned int rcv_addrs, subflows; 1773 int ret; 1774 1775 spin_lock_bh(&pernet->lock); 1776 rcv_addrs = pernet->add_addr_accept_max; 1777 ret = parse_limit(info, MPTCP_PM_ATTR_RCV_ADD_ADDRS, &rcv_addrs); 1778 if (ret) 1779 goto unlock; 1780 1781 subflows = pernet->subflows_max; 1782 ret = parse_limit(info, MPTCP_PM_ATTR_SUBFLOWS, &subflows); 1783 if (ret) 1784 goto unlock; 1785 1786 WRITE_ONCE(pernet->add_addr_accept_max, rcv_addrs); 1787 WRITE_ONCE(pernet->subflows_max, subflows); 1788 1789 unlock: 1790 spin_unlock_bh(&pernet->lock); 1791 return ret; 1792 } 1793 1794 int mptcp_pm_nl_get_limits_doit(struct sk_buff *skb, struct genl_info *info) 1795 { 1796 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1797 struct sk_buff *msg; 1798 void *reply; 1799 1800 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 1801 if (!msg) 1802 return -ENOMEM; 1803 1804 reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0, 1805 MPTCP_PM_CMD_GET_LIMITS); 1806 if (!reply) 1807 goto fail; 1808 1809 if (nla_put_u32(msg, MPTCP_PM_ATTR_RCV_ADD_ADDRS, 1810 READ_ONCE(pernet->add_addr_accept_max))) 1811 goto fail; 1812 1813 if (nla_put_u32(msg, MPTCP_PM_ATTR_SUBFLOWS, 1814 READ_ONCE(pernet->subflows_max))) 1815 goto fail; 1816 1817 genlmsg_end(msg, reply); 1818 return genlmsg_reply(msg, info); 1819 1820 fail: 1821 GENL_SET_ERR_MSG(info, "not enough space in Netlink message"); 1822 nlmsg_free(msg); 1823 return -EMSGSIZE; 1824 } 1825 1826 static void mptcp_pm_nl_fullmesh(struct mptcp_sock *msk, 1827 struct mptcp_addr_info *addr) 1828 { 1829 struct mptcp_rm_list list = { .nr = 0 }; 1830 1831 list.ids[list.nr++] = addr->id; 1832 1833 spin_lock_bh(&msk->pm.lock); 1834 mptcp_pm_nl_rm_subflow_received(msk, &list); 1835 mptcp_pm_create_subflow_or_signal_addr(msk); 1836 spin_unlock_bh(&msk->pm.lock); 1837 } 1838 1839 static int mptcp_nl_set_flags(struct net *net, 1840 struct mptcp_addr_info *addr, 1841 u8 bkup, u8 changed) 1842 { 1843 long s_slot = 0, s_num = 0; 1844 struct mptcp_sock *msk; 1845 int ret = -EINVAL; 1846 1847 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1848 struct sock *sk = (struct sock *)msk; 1849 1850 if (list_empty(&msk->conn_list) || mptcp_pm_is_userspace(msk)) 1851 goto next; 1852 1853 lock_sock(sk); 1854 if (changed & MPTCP_PM_ADDR_FLAG_BACKUP) 1855 ret = mptcp_pm_nl_mp_prio_send_ack(msk, addr, NULL, bkup); 1856 if (changed & MPTCP_PM_ADDR_FLAG_FULLMESH) 1857 mptcp_pm_nl_fullmesh(msk, addr); 1858 release_sock(sk); 1859 1860 next: 1861 sock_put(sk); 1862 cond_resched(); 1863 } 1864 1865 return ret; 1866 } 1867 1868 int mptcp_pm_nl_set_flags(struct net *net, struct mptcp_pm_addr_entry *addr, u8 bkup) 1869 { 1870 struct pm_nl_pernet *pernet = pm_nl_get_pernet(net); 1871 u8 changed, mask = MPTCP_PM_ADDR_FLAG_BACKUP | 1872 MPTCP_PM_ADDR_FLAG_FULLMESH; 1873 struct mptcp_pm_addr_entry *entry; 1874 u8 lookup_by_id = 0; 1875 1876 if (addr->addr.family == AF_UNSPEC) { 1877 lookup_by_id = 1; 1878 if (!addr->addr.id) 1879 return -EOPNOTSUPP; 1880 } 1881 1882 spin_lock_bh(&pernet->lock); 1883 entry = __lookup_addr(pernet, &addr->addr, lookup_by_id); 1884 if (!entry) { 1885 spin_unlock_bh(&pernet->lock); 1886 return -EINVAL; 1887 } 1888 if ((addr->flags & MPTCP_PM_ADDR_FLAG_FULLMESH) && 1889 (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) { 1890 spin_unlock_bh(&pernet->lock); 1891 return -EINVAL; 1892 } 1893 1894 changed = (addr->flags ^ entry->flags) & mask; 1895 entry->flags = (entry->flags & ~mask) | (addr->flags & mask); 1896 *addr = *entry; 1897 spin_unlock_bh(&pernet->lock); 1898 1899 mptcp_nl_set_flags(net, &addr->addr, bkup, changed); 1900 return 0; 1901 } 1902 1903 int mptcp_pm_nl_set_flags_doit(struct sk_buff *skb, struct genl_info *info) 1904 { 1905 struct mptcp_pm_addr_entry remote = { .addr = { .family = AF_UNSPEC }, }; 1906 struct mptcp_pm_addr_entry addr = { .addr = { .family = AF_UNSPEC }, }; 1907 struct nlattr *attr_rem = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE]; 1908 struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN]; 1909 struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR]; 1910 struct net *net = sock_net(skb->sk); 1911 u8 bkup = 0; 1912 int ret; 1913 1914 ret = mptcp_pm_parse_entry(attr, info, false, &addr); 1915 if (ret < 0) 1916 return ret; 1917 1918 if (attr_rem) { 1919 ret = mptcp_pm_parse_entry(attr_rem, info, false, &remote); 1920 if (ret < 0) 1921 return ret; 1922 } 1923 1924 if (addr.flags & MPTCP_PM_ADDR_FLAG_BACKUP) 1925 bkup = 1; 1926 1927 return mptcp_pm_set_flags(net, token, &addr, &remote, bkup); 1928 } 1929 1930 static void mptcp_nl_mcast_send(struct net *net, struct sk_buff *nlskb, gfp_t gfp) 1931 { 1932 genlmsg_multicast_netns(&mptcp_genl_family, net, 1933 nlskb, 0, MPTCP_PM_EV_GRP_OFFSET, gfp); 1934 } 1935 1936 bool mptcp_userspace_pm_active(const struct mptcp_sock *msk) 1937 { 1938 return genl_has_listeners(&mptcp_genl_family, 1939 sock_net((const struct sock *)msk), 1940 MPTCP_PM_EV_GRP_OFFSET); 1941 } 1942 1943 static int mptcp_event_add_subflow(struct sk_buff *skb, const struct sock *ssk) 1944 { 1945 const struct inet_sock *issk = inet_sk(ssk); 1946 const struct mptcp_subflow_context *sf; 1947 1948 if (nla_put_u16(skb, MPTCP_ATTR_FAMILY, ssk->sk_family)) 1949 return -EMSGSIZE; 1950 1951 switch (ssk->sk_family) { 1952 case AF_INET: 1953 if (nla_put_in_addr(skb, MPTCP_ATTR_SADDR4, issk->inet_saddr)) 1954 return -EMSGSIZE; 1955 if (nla_put_in_addr(skb, MPTCP_ATTR_DADDR4, issk->inet_daddr)) 1956 return -EMSGSIZE; 1957 break; 1958 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1959 case AF_INET6: { 1960 const struct ipv6_pinfo *np = inet6_sk(ssk); 1961 1962 if (nla_put_in6_addr(skb, MPTCP_ATTR_SADDR6, &np->saddr)) 1963 return -EMSGSIZE; 1964 if (nla_put_in6_addr(skb, MPTCP_ATTR_DADDR6, &ssk->sk_v6_daddr)) 1965 return -EMSGSIZE; 1966 break; 1967 } 1968 #endif 1969 default: 1970 WARN_ON_ONCE(1); 1971 return -EMSGSIZE; 1972 } 1973 1974 if (nla_put_be16(skb, MPTCP_ATTR_SPORT, issk->inet_sport)) 1975 return -EMSGSIZE; 1976 if (nla_put_be16(skb, MPTCP_ATTR_DPORT, issk->inet_dport)) 1977 return -EMSGSIZE; 1978 1979 sf = mptcp_subflow_ctx(ssk); 1980 if (WARN_ON_ONCE(!sf)) 1981 return -EINVAL; 1982 1983 if (nla_put_u8(skb, MPTCP_ATTR_LOC_ID, sf->local_id)) 1984 return -EMSGSIZE; 1985 1986 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, sf->remote_id)) 1987 return -EMSGSIZE; 1988 1989 return 0; 1990 } 1991 1992 static int mptcp_event_put_token_and_ssk(struct sk_buff *skb, 1993 const struct mptcp_sock *msk, 1994 const struct sock *ssk) 1995 { 1996 const struct sock *sk = (const struct sock *)msk; 1997 const struct mptcp_subflow_context *sf; 1998 u8 sk_err; 1999 2000 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token)) 2001 return -EMSGSIZE; 2002 2003 if (mptcp_event_add_subflow(skb, ssk)) 2004 return -EMSGSIZE; 2005 2006 sf = mptcp_subflow_ctx(ssk); 2007 if (WARN_ON_ONCE(!sf)) 2008 return -EINVAL; 2009 2010 if (nla_put_u8(skb, MPTCP_ATTR_BACKUP, sf->backup)) 2011 return -EMSGSIZE; 2012 2013 if (ssk->sk_bound_dev_if && 2014 nla_put_s32(skb, MPTCP_ATTR_IF_IDX, ssk->sk_bound_dev_if)) 2015 return -EMSGSIZE; 2016 2017 sk_err = READ_ONCE(ssk->sk_err); 2018 if (sk_err && sk->sk_state == TCP_ESTABLISHED && 2019 nla_put_u8(skb, MPTCP_ATTR_ERROR, sk_err)) 2020 return -EMSGSIZE; 2021 2022 return 0; 2023 } 2024 2025 static int mptcp_event_sub_established(struct sk_buff *skb, 2026 const struct mptcp_sock *msk, 2027 const struct sock *ssk) 2028 { 2029 return mptcp_event_put_token_and_ssk(skb, msk, ssk); 2030 } 2031 2032 static int mptcp_event_sub_closed(struct sk_buff *skb, 2033 const struct mptcp_sock *msk, 2034 const struct sock *ssk) 2035 { 2036 const struct mptcp_subflow_context *sf; 2037 2038 if (mptcp_event_put_token_and_ssk(skb, msk, ssk)) 2039 return -EMSGSIZE; 2040 2041 sf = mptcp_subflow_ctx(ssk); 2042 if (!sf->reset_seen) 2043 return 0; 2044 2045 if (nla_put_u32(skb, MPTCP_ATTR_RESET_REASON, sf->reset_reason)) 2046 return -EMSGSIZE; 2047 2048 if (nla_put_u32(skb, MPTCP_ATTR_RESET_FLAGS, sf->reset_transient)) 2049 return -EMSGSIZE; 2050 2051 return 0; 2052 } 2053 2054 static int mptcp_event_created(struct sk_buff *skb, 2055 const struct mptcp_sock *msk, 2056 const struct sock *ssk) 2057 { 2058 int err = nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token); 2059 2060 if (err) 2061 return err; 2062 2063 if (nla_put_u8(skb, MPTCP_ATTR_SERVER_SIDE, READ_ONCE(msk->pm.server_side))) 2064 return -EMSGSIZE; 2065 2066 return mptcp_event_add_subflow(skb, ssk); 2067 } 2068 2069 void mptcp_event_addr_removed(const struct mptcp_sock *msk, uint8_t id) 2070 { 2071 struct net *net = sock_net((const struct sock *)msk); 2072 struct nlmsghdr *nlh; 2073 struct sk_buff *skb; 2074 2075 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2076 return; 2077 2078 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); 2079 if (!skb) 2080 return; 2081 2082 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, MPTCP_EVENT_REMOVED); 2083 if (!nlh) 2084 goto nla_put_failure; 2085 2086 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token)) 2087 goto nla_put_failure; 2088 2089 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, id)) 2090 goto nla_put_failure; 2091 2092 genlmsg_end(skb, nlh); 2093 mptcp_nl_mcast_send(net, skb, GFP_ATOMIC); 2094 return; 2095 2096 nla_put_failure: 2097 nlmsg_free(skb); 2098 } 2099 2100 void mptcp_event_addr_announced(const struct sock *ssk, 2101 const struct mptcp_addr_info *info) 2102 { 2103 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 2104 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 2105 struct net *net = sock_net(ssk); 2106 struct nlmsghdr *nlh; 2107 struct sk_buff *skb; 2108 2109 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2110 return; 2111 2112 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); 2113 if (!skb) 2114 return; 2115 2116 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, 2117 MPTCP_EVENT_ANNOUNCED); 2118 if (!nlh) 2119 goto nla_put_failure; 2120 2121 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token)) 2122 goto nla_put_failure; 2123 2124 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, info->id)) 2125 goto nla_put_failure; 2126 2127 if (nla_put_be16(skb, MPTCP_ATTR_DPORT, 2128 info->port == 0 ? 2129 inet_sk(ssk)->inet_dport : 2130 info->port)) 2131 goto nla_put_failure; 2132 2133 switch (info->family) { 2134 case AF_INET: 2135 if (nla_put_in_addr(skb, MPTCP_ATTR_DADDR4, info->addr.s_addr)) 2136 goto nla_put_failure; 2137 break; 2138 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 2139 case AF_INET6: 2140 if (nla_put_in6_addr(skb, MPTCP_ATTR_DADDR6, &info->addr6)) 2141 goto nla_put_failure; 2142 break; 2143 #endif 2144 default: 2145 WARN_ON_ONCE(1); 2146 goto nla_put_failure; 2147 } 2148 2149 genlmsg_end(skb, nlh); 2150 mptcp_nl_mcast_send(net, skb, GFP_ATOMIC); 2151 return; 2152 2153 nla_put_failure: 2154 nlmsg_free(skb); 2155 } 2156 2157 void mptcp_event_pm_listener(const struct sock *ssk, 2158 enum mptcp_event_type event) 2159 { 2160 const struct inet_sock *issk = inet_sk(ssk); 2161 struct net *net = sock_net(ssk); 2162 struct nlmsghdr *nlh; 2163 struct sk_buff *skb; 2164 2165 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2166 return; 2167 2168 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 2169 if (!skb) 2170 return; 2171 2172 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, event); 2173 if (!nlh) 2174 goto nla_put_failure; 2175 2176 if (nla_put_u16(skb, MPTCP_ATTR_FAMILY, ssk->sk_family)) 2177 goto nla_put_failure; 2178 2179 if (nla_put_be16(skb, MPTCP_ATTR_SPORT, issk->inet_sport)) 2180 goto nla_put_failure; 2181 2182 switch (ssk->sk_family) { 2183 case AF_INET: 2184 if (nla_put_in_addr(skb, MPTCP_ATTR_SADDR4, issk->inet_saddr)) 2185 goto nla_put_failure; 2186 break; 2187 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 2188 case AF_INET6: { 2189 const struct ipv6_pinfo *np = inet6_sk(ssk); 2190 2191 if (nla_put_in6_addr(skb, MPTCP_ATTR_SADDR6, &np->saddr)) 2192 goto nla_put_failure; 2193 break; 2194 } 2195 #endif 2196 default: 2197 WARN_ON_ONCE(1); 2198 goto nla_put_failure; 2199 } 2200 2201 genlmsg_end(skb, nlh); 2202 mptcp_nl_mcast_send(net, skb, GFP_KERNEL); 2203 return; 2204 2205 nla_put_failure: 2206 nlmsg_free(skb); 2207 } 2208 2209 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk, 2210 const struct sock *ssk, gfp_t gfp) 2211 { 2212 struct net *net = sock_net((const struct sock *)msk); 2213 struct nlmsghdr *nlh; 2214 struct sk_buff *skb; 2215 2216 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2217 return; 2218 2219 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, gfp); 2220 if (!skb) 2221 return; 2222 2223 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, type); 2224 if (!nlh) 2225 goto nla_put_failure; 2226 2227 switch (type) { 2228 case MPTCP_EVENT_UNSPEC: 2229 WARN_ON_ONCE(1); 2230 break; 2231 case MPTCP_EVENT_CREATED: 2232 case MPTCP_EVENT_ESTABLISHED: 2233 if (mptcp_event_created(skb, msk, ssk) < 0) 2234 goto nla_put_failure; 2235 break; 2236 case MPTCP_EVENT_CLOSED: 2237 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token) < 0) 2238 goto nla_put_failure; 2239 break; 2240 case MPTCP_EVENT_ANNOUNCED: 2241 case MPTCP_EVENT_REMOVED: 2242 /* call mptcp_event_addr_announced()/removed instead */ 2243 WARN_ON_ONCE(1); 2244 break; 2245 case MPTCP_EVENT_SUB_ESTABLISHED: 2246 case MPTCP_EVENT_SUB_PRIORITY: 2247 if (mptcp_event_sub_established(skb, msk, ssk) < 0) 2248 goto nla_put_failure; 2249 break; 2250 case MPTCP_EVENT_SUB_CLOSED: 2251 if (mptcp_event_sub_closed(skb, msk, ssk) < 0) 2252 goto nla_put_failure; 2253 break; 2254 case MPTCP_EVENT_LISTENER_CREATED: 2255 case MPTCP_EVENT_LISTENER_CLOSED: 2256 break; 2257 } 2258 2259 genlmsg_end(skb, nlh); 2260 mptcp_nl_mcast_send(net, skb, gfp); 2261 return; 2262 2263 nla_put_failure: 2264 nlmsg_free(skb); 2265 } 2266 2267 static struct genl_family mptcp_genl_family __ro_after_init = { 2268 .name = MPTCP_PM_NAME, 2269 .version = MPTCP_PM_VER, 2270 .netnsok = true, 2271 .module = THIS_MODULE, 2272 .ops = mptcp_pm_nl_ops, 2273 .n_ops = ARRAY_SIZE(mptcp_pm_nl_ops), 2274 .resv_start_op = MPTCP_PM_CMD_SUBFLOW_DESTROY + 1, 2275 .mcgrps = mptcp_pm_mcgrps, 2276 .n_mcgrps = ARRAY_SIZE(mptcp_pm_mcgrps), 2277 }; 2278 2279 static int __net_init pm_nl_init_net(struct net *net) 2280 { 2281 struct pm_nl_pernet *pernet = pm_nl_get_pernet(net); 2282 2283 INIT_LIST_HEAD_RCU(&pernet->local_addr_list); 2284 2285 /* Cit. 2 subflows ought to be enough for anybody. */ 2286 pernet->subflows_max = 2; 2287 pernet->next_id = 1; 2288 pernet->stale_loss_cnt = 4; 2289 spin_lock_init(&pernet->lock); 2290 2291 /* No need to initialize other pernet fields, the struct is zeroed at 2292 * allocation time. 2293 */ 2294 2295 return 0; 2296 } 2297 2298 static void __net_exit pm_nl_exit_net(struct list_head *net_list) 2299 { 2300 struct net *net; 2301 2302 list_for_each_entry(net, net_list, exit_list) { 2303 struct pm_nl_pernet *pernet = pm_nl_get_pernet(net); 2304 2305 /* net is removed from namespace list, can't race with 2306 * other modifiers, also netns core already waited for a 2307 * RCU grace period. 2308 */ 2309 __flush_addrs(&pernet->local_addr_list); 2310 } 2311 } 2312 2313 static struct pernet_operations mptcp_pm_pernet_ops = { 2314 .init = pm_nl_init_net, 2315 .exit_batch = pm_nl_exit_net, 2316 .id = &pm_nl_pernet_id, 2317 .size = sizeof(struct pm_nl_pernet), 2318 }; 2319 2320 void __init mptcp_pm_nl_init(void) 2321 { 2322 if (register_pernet_subsys(&mptcp_pm_pernet_ops) < 0) 2323 panic("Failed to register MPTCP PM pernet subsystem.\n"); 2324 2325 if (genl_register_family(&mptcp_genl_family)) 2326 panic("Failed to register MPTCP PM netlink family\n"); 2327 } 2328