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/inet_common.h> 12 #include <net/netns/generic.h> 13 #include <net/mptcp.h> 14 15 #include "protocol.h" 16 #include "mib.h" 17 #include "mptcp_pm_gen.h" 18 19 static int pm_nl_pernet_id; 20 21 struct mptcp_pm_add_entry { 22 struct list_head list; 23 struct mptcp_addr_info addr; 24 u8 retrans_times; 25 struct timer_list add_timer; 26 struct mptcp_sock *sock; 27 }; 28 29 struct pm_nl_pernet { 30 /* protects pernet updates */ 31 spinlock_t lock; 32 struct list_head local_addr_list; 33 unsigned int addrs; 34 unsigned int stale_loss_cnt; 35 unsigned int add_addr_signal_max; 36 unsigned int add_addr_accept_max; 37 unsigned int local_addr_max; 38 unsigned int subflows_max; 39 unsigned int next_id; 40 DECLARE_BITMAP(id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); 41 }; 42 43 #define MPTCP_PM_ADDR_MAX 8 44 #define ADD_ADDR_RETRANS_MAX 3 45 46 static struct pm_nl_pernet *pm_nl_get_pernet(const struct net *net) 47 { 48 return net_generic(net, pm_nl_pernet_id); 49 } 50 51 static struct pm_nl_pernet * 52 pm_nl_get_pernet_from_msk(const struct mptcp_sock *msk) 53 { 54 return pm_nl_get_pernet(sock_net((struct sock *)msk)); 55 } 56 57 bool mptcp_addresses_equal(const struct mptcp_addr_info *a, 58 const struct mptcp_addr_info *b, bool use_port) 59 { 60 bool addr_equals = false; 61 62 if (a->family == b->family) { 63 if (a->family == AF_INET) 64 addr_equals = a->addr.s_addr == b->addr.s_addr; 65 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 66 else 67 addr_equals = !ipv6_addr_cmp(&a->addr6, &b->addr6); 68 } else if (a->family == AF_INET) { 69 if (ipv6_addr_v4mapped(&b->addr6)) 70 addr_equals = a->addr.s_addr == b->addr6.s6_addr32[3]; 71 } else if (b->family == AF_INET) { 72 if (ipv6_addr_v4mapped(&a->addr6)) 73 addr_equals = a->addr6.s6_addr32[3] == b->addr.s_addr; 74 #endif 75 } 76 77 if (!addr_equals) 78 return false; 79 if (!use_port) 80 return true; 81 82 return a->port == b->port; 83 } 84 85 void mptcp_local_address(const struct sock_common *skc, struct mptcp_addr_info *addr) 86 { 87 addr->family = skc->skc_family; 88 addr->port = htons(skc->skc_num); 89 if (addr->family == AF_INET) 90 addr->addr.s_addr = skc->skc_rcv_saddr; 91 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 92 else if (addr->family == AF_INET6) 93 addr->addr6 = skc->skc_v6_rcv_saddr; 94 #endif 95 } 96 97 static void remote_address(const struct sock_common *skc, 98 struct mptcp_addr_info *addr) 99 { 100 addr->family = skc->skc_family; 101 addr->port = skc->skc_dport; 102 if (addr->family == AF_INET) 103 addr->addr.s_addr = skc->skc_daddr; 104 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 105 else if (addr->family == AF_INET6) 106 addr->addr6 = skc->skc_v6_daddr; 107 #endif 108 } 109 110 static bool lookup_subflow_by_saddr(const struct list_head *list, 111 const struct mptcp_addr_info *saddr) 112 { 113 struct mptcp_subflow_context *subflow; 114 struct mptcp_addr_info cur; 115 struct sock_common *skc; 116 117 list_for_each_entry(subflow, list, node) { 118 skc = (struct sock_common *)mptcp_subflow_tcp_sock(subflow); 119 120 mptcp_local_address(skc, &cur); 121 if (mptcp_addresses_equal(&cur, saddr, saddr->port)) 122 return true; 123 } 124 125 return false; 126 } 127 128 static bool lookup_subflow_by_daddr(const struct list_head *list, 129 const struct mptcp_addr_info *daddr) 130 { 131 struct mptcp_subflow_context *subflow; 132 struct mptcp_addr_info cur; 133 struct sock_common *skc; 134 135 list_for_each_entry(subflow, list, node) { 136 skc = (struct sock_common *)mptcp_subflow_tcp_sock(subflow); 137 138 remote_address(skc, &cur); 139 if (mptcp_addresses_equal(&cur, daddr, daddr->port)) 140 return true; 141 } 142 143 return false; 144 } 145 146 static struct mptcp_pm_addr_entry * 147 select_local_address(const struct pm_nl_pernet *pernet, 148 const struct mptcp_sock *msk) 149 { 150 struct mptcp_pm_addr_entry *entry, *ret = NULL; 151 152 msk_owned_by_me(msk); 153 154 rcu_read_lock(); 155 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 156 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW)) 157 continue; 158 159 if (!test_bit(entry->addr.id, msk->pm.id_avail_bitmap)) 160 continue; 161 162 ret = entry; 163 break; 164 } 165 rcu_read_unlock(); 166 return ret; 167 } 168 169 static struct mptcp_pm_addr_entry * 170 select_signal_address(struct pm_nl_pernet *pernet, const struct mptcp_sock *msk) 171 { 172 struct mptcp_pm_addr_entry *entry, *ret = NULL; 173 174 rcu_read_lock(); 175 /* do not keep any additional per socket state, just signal 176 * the address list in order. 177 * Note: removal from the local address list during the msk life-cycle 178 * can lead to additional addresses not being announced. 179 */ 180 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 181 if (!test_bit(entry->addr.id, msk->pm.id_avail_bitmap)) 182 continue; 183 184 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) 185 continue; 186 187 ret = entry; 188 break; 189 } 190 rcu_read_unlock(); 191 return ret; 192 } 193 194 unsigned int mptcp_pm_get_add_addr_signal_max(const struct mptcp_sock *msk) 195 { 196 const struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk); 197 198 return READ_ONCE(pernet->add_addr_signal_max); 199 } 200 EXPORT_SYMBOL_GPL(mptcp_pm_get_add_addr_signal_max); 201 202 unsigned int mptcp_pm_get_add_addr_accept_max(const struct mptcp_sock *msk) 203 { 204 struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk); 205 206 return READ_ONCE(pernet->add_addr_accept_max); 207 } 208 EXPORT_SYMBOL_GPL(mptcp_pm_get_add_addr_accept_max); 209 210 unsigned int mptcp_pm_get_subflows_max(const struct mptcp_sock *msk) 211 { 212 struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk); 213 214 return READ_ONCE(pernet->subflows_max); 215 } 216 EXPORT_SYMBOL_GPL(mptcp_pm_get_subflows_max); 217 218 unsigned int mptcp_pm_get_local_addr_max(const struct mptcp_sock *msk) 219 { 220 struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk); 221 222 return READ_ONCE(pernet->local_addr_max); 223 } 224 EXPORT_SYMBOL_GPL(mptcp_pm_get_local_addr_max); 225 226 bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk) 227 { 228 struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk); 229 230 if (msk->pm.subflows == mptcp_pm_get_subflows_max(msk) || 231 (find_next_and_bit(pernet->id_bitmap, msk->pm.id_avail_bitmap, 232 MPTCP_PM_MAX_ADDR_ID + 1, 0) == MPTCP_PM_MAX_ADDR_ID + 1)) { 233 WRITE_ONCE(msk->pm.work_pending, false); 234 return false; 235 } 236 return true; 237 } 238 239 struct mptcp_pm_add_entry * 240 mptcp_lookup_anno_list_by_saddr(const struct mptcp_sock *msk, 241 const struct mptcp_addr_info *addr) 242 { 243 struct mptcp_pm_add_entry *entry; 244 245 lockdep_assert_held(&msk->pm.lock); 246 247 list_for_each_entry(entry, &msk->pm.anno_list, list) { 248 if (mptcp_addresses_equal(&entry->addr, addr, true)) 249 return entry; 250 } 251 252 return NULL; 253 } 254 255 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk) 256 { 257 struct mptcp_pm_add_entry *entry; 258 struct mptcp_addr_info saddr; 259 bool ret = false; 260 261 mptcp_local_address((struct sock_common *)sk, &saddr); 262 263 spin_lock_bh(&msk->pm.lock); 264 list_for_each_entry(entry, &msk->pm.anno_list, list) { 265 if (mptcp_addresses_equal(&entry->addr, &saddr, true)) { 266 ret = true; 267 goto out; 268 } 269 } 270 271 out: 272 spin_unlock_bh(&msk->pm.lock); 273 return ret; 274 } 275 276 static void mptcp_pm_add_timer(struct timer_list *timer) 277 { 278 struct mptcp_pm_add_entry *entry = from_timer(entry, timer, add_timer); 279 struct mptcp_sock *msk = entry->sock; 280 struct sock *sk = (struct sock *)msk; 281 282 pr_debug("msk=%p", msk); 283 284 if (!msk) 285 return; 286 287 if (inet_sk_state_load(sk) == TCP_CLOSE) 288 return; 289 290 if (!entry->addr.id) 291 return; 292 293 if (mptcp_pm_should_add_signal_addr(msk)) { 294 sk_reset_timer(sk, timer, jiffies + TCP_RTO_MAX / 8); 295 goto out; 296 } 297 298 spin_lock_bh(&msk->pm.lock); 299 300 if (!mptcp_pm_should_add_signal_addr(msk)) { 301 pr_debug("retransmit ADD_ADDR id=%d", entry->addr.id); 302 mptcp_pm_announce_addr(msk, &entry->addr, false); 303 mptcp_pm_add_addr_send_ack(msk); 304 entry->retrans_times++; 305 } 306 307 if (entry->retrans_times < ADD_ADDR_RETRANS_MAX) 308 sk_reset_timer(sk, timer, 309 jiffies + mptcp_get_add_addr_timeout(sock_net(sk))); 310 311 spin_unlock_bh(&msk->pm.lock); 312 313 if (entry->retrans_times == ADD_ADDR_RETRANS_MAX) 314 mptcp_pm_subflow_established(msk); 315 316 out: 317 __sock_put(sk); 318 } 319 320 struct mptcp_pm_add_entry * 321 mptcp_pm_del_add_timer(struct mptcp_sock *msk, 322 const struct mptcp_addr_info *addr, bool check_id) 323 { 324 struct mptcp_pm_add_entry *entry; 325 struct sock *sk = (struct sock *)msk; 326 327 spin_lock_bh(&msk->pm.lock); 328 entry = mptcp_lookup_anno_list_by_saddr(msk, addr); 329 if (entry && (!check_id || entry->addr.id == addr->id)) 330 entry->retrans_times = ADD_ADDR_RETRANS_MAX; 331 spin_unlock_bh(&msk->pm.lock); 332 333 if (entry && (!check_id || entry->addr.id == addr->id)) 334 sk_stop_timer_sync(sk, &entry->add_timer); 335 336 return entry; 337 } 338 339 bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk, 340 const struct mptcp_addr_info *addr) 341 { 342 struct mptcp_pm_add_entry *add_entry = NULL; 343 struct sock *sk = (struct sock *)msk; 344 struct net *net = sock_net(sk); 345 346 lockdep_assert_held(&msk->pm.lock); 347 348 add_entry = mptcp_lookup_anno_list_by_saddr(msk, addr); 349 350 if (add_entry) { 351 if (mptcp_pm_is_kernel(msk)) 352 return false; 353 354 sk_reset_timer(sk, &add_entry->add_timer, 355 jiffies + mptcp_get_add_addr_timeout(net)); 356 return true; 357 } 358 359 add_entry = kmalloc(sizeof(*add_entry), GFP_ATOMIC); 360 if (!add_entry) 361 return false; 362 363 list_add(&add_entry->list, &msk->pm.anno_list); 364 365 add_entry->addr = *addr; 366 add_entry->sock = msk; 367 add_entry->retrans_times = 0; 368 369 timer_setup(&add_entry->add_timer, mptcp_pm_add_timer, 0); 370 sk_reset_timer(sk, &add_entry->add_timer, 371 jiffies + mptcp_get_add_addr_timeout(net)); 372 373 return true; 374 } 375 376 void mptcp_pm_free_anno_list(struct mptcp_sock *msk) 377 { 378 struct mptcp_pm_add_entry *entry, *tmp; 379 struct sock *sk = (struct sock *)msk; 380 LIST_HEAD(free_list); 381 382 pr_debug("msk=%p", msk); 383 384 spin_lock_bh(&msk->pm.lock); 385 list_splice_init(&msk->pm.anno_list, &free_list); 386 spin_unlock_bh(&msk->pm.lock); 387 388 list_for_each_entry_safe(entry, tmp, &free_list, list) { 389 sk_stop_timer_sync(sk, &entry->add_timer); 390 kfree(entry); 391 } 392 } 393 394 /* Fill all the remote addresses into the array addrs[], 395 * and return the array size. 396 */ 397 static unsigned int fill_remote_addresses_vec(struct mptcp_sock *msk, 398 struct mptcp_addr_info *local, 399 bool fullmesh, 400 struct mptcp_addr_info *addrs) 401 { 402 bool deny_id0 = READ_ONCE(msk->pm.remote_deny_join_id0); 403 struct sock *sk = (struct sock *)msk, *ssk; 404 struct mptcp_subflow_context *subflow; 405 struct mptcp_addr_info remote = { 0 }; 406 unsigned int subflows_max; 407 int i = 0; 408 409 subflows_max = mptcp_pm_get_subflows_max(msk); 410 remote_address((struct sock_common *)sk, &remote); 411 412 /* Non-fullmesh endpoint, fill in the single entry 413 * corresponding to the primary MPC subflow remote address 414 */ 415 if (!fullmesh) { 416 if (deny_id0) 417 return 0; 418 419 if (!mptcp_pm_addr_families_match(sk, local, &remote)) 420 return 0; 421 422 msk->pm.subflows++; 423 addrs[i++] = remote; 424 } else { 425 DECLARE_BITMAP(unavail_id, MPTCP_PM_MAX_ADDR_ID + 1); 426 427 /* Forbid creation of new subflows matching existing 428 * ones, possibly already created by incoming ADD_ADDR 429 */ 430 bitmap_zero(unavail_id, MPTCP_PM_MAX_ADDR_ID + 1); 431 mptcp_for_each_subflow(msk, subflow) 432 if (READ_ONCE(subflow->local_id) == local->id) 433 __set_bit(subflow->remote_id, unavail_id); 434 435 mptcp_for_each_subflow(msk, subflow) { 436 ssk = mptcp_subflow_tcp_sock(subflow); 437 remote_address((struct sock_common *)ssk, &addrs[i]); 438 addrs[i].id = READ_ONCE(subflow->remote_id); 439 if (deny_id0 && !addrs[i].id) 440 continue; 441 442 if (test_bit(addrs[i].id, unavail_id)) 443 continue; 444 445 if (!mptcp_pm_addr_families_match(sk, local, &addrs[i])) 446 continue; 447 448 if (msk->pm.subflows < subflows_max) { 449 /* forbid creating multiple address towards 450 * this id 451 */ 452 __set_bit(addrs[i].id, unavail_id); 453 msk->pm.subflows++; 454 i++; 455 } 456 } 457 } 458 459 return i; 460 } 461 462 static void __mptcp_pm_send_ack(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow, 463 bool prio, bool backup) 464 { 465 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 466 bool slow; 467 468 pr_debug("send ack for %s", 469 prio ? "mp_prio" : (mptcp_pm_should_add_signal(msk) ? "add_addr" : "rm_addr")); 470 471 slow = lock_sock_fast(ssk); 472 if (prio) { 473 subflow->send_mp_prio = 1; 474 subflow->backup = backup; 475 subflow->request_bkup = backup; 476 } 477 478 __mptcp_subflow_send_ack(ssk); 479 unlock_sock_fast(ssk, slow); 480 } 481 482 static void mptcp_pm_send_ack(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow, 483 bool prio, bool backup) 484 { 485 spin_unlock_bh(&msk->pm.lock); 486 __mptcp_pm_send_ack(msk, subflow, prio, backup); 487 spin_lock_bh(&msk->pm.lock); 488 } 489 490 static struct mptcp_pm_addr_entry * 491 __lookup_addr_by_id(struct pm_nl_pernet *pernet, unsigned int id) 492 { 493 struct mptcp_pm_addr_entry *entry; 494 495 list_for_each_entry(entry, &pernet->local_addr_list, list) { 496 if (entry->addr.id == id) 497 return entry; 498 } 499 return NULL; 500 } 501 502 static struct mptcp_pm_addr_entry * 503 __lookup_addr(struct pm_nl_pernet *pernet, const struct mptcp_addr_info *info) 504 { 505 struct mptcp_pm_addr_entry *entry; 506 507 list_for_each_entry(entry, &pernet->local_addr_list, list) { 508 if (mptcp_addresses_equal(&entry->addr, info, entry->addr.port)) 509 return entry; 510 } 511 return NULL; 512 } 513 514 static void mptcp_pm_create_subflow_or_signal_addr(struct mptcp_sock *msk) 515 { 516 struct sock *sk = (struct sock *)msk; 517 struct mptcp_pm_addr_entry *local; 518 unsigned int add_addr_signal_max; 519 unsigned int local_addr_max; 520 struct pm_nl_pernet *pernet; 521 unsigned int subflows_max; 522 523 pernet = pm_nl_get_pernet(sock_net(sk)); 524 525 add_addr_signal_max = mptcp_pm_get_add_addr_signal_max(msk); 526 local_addr_max = mptcp_pm_get_local_addr_max(msk); 527 subflows_max = mptcp_pm_get_subflows_max(msk); 528 529 /* do lazy endpoint usage accounting for the MPC subflows */ 530 if (unlikely(!(msk->pm.status & BIT(MPTCP_PM_MPC_ENDPOINT_ACCOUNTED))) && msk->first) { 531 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(msk->first); 532 struct mptcp_pm_addr_entry *entry; 533 struct mptcp_addr_info mpc_addr; 534 bool backup = false; 535 536 mptcp_local_address((struct sock_common *)msk->first, &mpc_addr); 537 rcu_read_lock(); 538 entry = __lookup_addr(pernet, &mpc_addr); 539 if (entry) { 540 __clear_bit(entry->addr.id, msk->pm.id_avail_bitmap); 541 msk->mpc_endpoint_id = entry->addr.id; 542 backup = !!(entry->flags & MPTCP_PM_ADDR_FLAG_BACKUP); 543 } 544 rcu_read_unlock(); 545 546 if (backup) 547 mptcp_pm_send_ack(msk, subflow, true, backup); 548 549 msk->pm.status |= BIT(MPTCP_PM_MPC_ENDPOINT_ACCOUNTED); 550 } 551 552 pr_debug("local %d:%d signal %d:%d subflows %d:%d\n", 553 msk->pm.local_addr_used, local_addr_max, 554 msk->pm.add_addr_signaled, add_addr_signal_max, 555 msk->pm.subflows, subflows_max); 556 557 /* check first for announce */ 558 if (msk->pm.add_addr_signaled < add_addr_signal_max) { 559 local = select_signal_address(pernet, msk); 560 561 /* due to racing events on both ends we can reach here while 562 * previous add address is still running: if we invoke now 563 * mptcp_pm_announce_addr(), that will fail and the 564 * corresponding id will be marked as used. 565 * Instead let the PM machinery reschedule us when the 566 * current address announce will be completed. 567 */ 568 if (msk->pm.addr_signal & BIT(MPTCP_ADD_ADDR_SIGNAL)) 569 return; 570 571 if (local) { 572 if (mptcp_pm_alloc_anno_list(msk, &local->addr)) { 573 __clear_bit(local->addr.id, msk->pm.id_avail_bitmap); 574 msk->pm.add_addr_signaled++; 575 mptcp_pm_announce_addr(msk, &local->addr, false); 576 mptcp_pm_nl_addr_send_ack(msk); 577 } 578 } 579 } 580 581 /* check if should create a new subflow */ 582 while (msk->pm.local_addr_used < local_addr_max && 583 msk->pm.subflows < subflows_max) { 584 struct mptcp_addr_info addrs[MPTCP_PM_ADDR_MAX]; 585 bool fullmesh; 586 int i, nr; 587 588 local = select_local_address(pernet, msk); 589 if (!local) 590 break; 591 592 fullmesh = !!(local->flags & MPTCP_PM_ADDR_FLAG_FULLMESH); 593 594 msk->pm.local_addr_used++; 595 __clear_bit(local->addr.id, msk->pm.id_avail_bitmap); 596 nr = fill_remote_addresses_vec(msk, &local->addr, fullmesh, addrs); 597 if (nr == 0) 598 continue; 599 600 spin_unlock_bh(&msk->pm.lock); 601 for (i = 0; i < nr; i++) 602 __mptcp_subflow_connect(sk, &local->addr, &addrs[i]); 603 spin_lock_bh(&msk->pm.lock); 604 } 605 mptcp_pm_nl_check_work_pending(msk); 606 } 607 608 static void mptcp_pm_nl_fully_established(struct mptcp_sock *msk) 609 { 610 mptcp_pm_create_subflow_or_signal_addr(msk); 611 } 612 613 static void mptcp_pm_nl_subflow_established(struct mptcp_sock *msk) 614 { 615 mptcp_pm_create_subflow_or_signal_addr(msk); 616 } 617 618 /* Fill all the local addresses into the array addrs[], 619 * and return the array size. 620 */ 621 static unsigned int fill_local_addresses_vec(struct mptcp_sock *msk, 622 struct mptcp_addr_info *remote, 623 struct mptcp_addr_info *addrs) 624 { 625 struct sock *sk = (struct sock *)msk; 626 struct mptcp_pm_addr_entry *entry; 627 struct pm_nl_pernet *pernet; 628 unsigned int subflows_max; 629 int i = 0; 630 631 pernet = pm_nl_get_pernet_from_msk(msk); 632 subflows_max = mptcp_pm_get_subflows_max(msk); 633 634 rcu_read_lock(); 635 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 636 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_FULLMESH)) 637 continue; 638 639 if (!mptcp_pm_addr_families_match(sk, &entry->addr, remote)) 640 continue; 641 642 if (msk->pm.subflows < subflows_max) { 643 msk->pm.subflows++; 644 addrs[i++] = entry->addr; 645 } 646 } 647 rcu_read_unlock(); 648 649 /* If the array is empty, fill in the single 650 * 'IPADDRANY' local address 651 */ 652 if (!i) { 653 struct mptcp_addr_info local; 654 655 memset(&local, 0, sizeof(local)); 656 local.family = 657 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 658 remote->family == AF_INET6 && 659 ipv6_addr_v4mapped(&remote->addr6) ? AF_INET : 660 #endif 661 remote->family; 662 663 if (!mptcp_pm_addr_families_match(sk, &local, remote)) 664 return 0; 665 666 msk->pm.subflows++; 667 addrs[i++] = local; 668 } 669 670 return i; 671 } 672 673 static void mptcp_pm_nl_add_addr_received(struct mptcp_sock *msk) 674 { 675 struct mptcp_addr_info addrs[MPTCP_PM_ADDR_MAX]; 676 struct sock *sk = (struct sock *)msk; 677 unsigned int add_addr_accept_max; 678 struct mptcp_addr_info remote; 679 unsigned int subflows_max; 680 bool sf_created = false; 681 int i, nr; 682 683 add_addr_accept_max = mptcp_pm_get_add_addr_accept_max(msk); 684 subflows_max = mptcp_pm_get_subflows_max(msk); 685 686 pr_debug("accepted %d:%d remote family %d", 687 msk->pm.add_addr_accepted, add_addr_accept_max, 688 msk->pm.remote.family); 689 690 remote = msk->pm.remote; 691 mptcp_pm_announce_addr(msk, &remote, true); 692 mptcp_pm_nl_addr_send_ack(msk); 693 694 if (lookup_subflow_by_daddr(&msk->conn_list, &remote)) 695 return; 696 697 /* pick id 0 port, if none is provided the remote address */ 698 if (!remote.port) 699 remote.port = sk->sk_dport; 700 701 /* connect to the specified remote address, using whatever 702 * local address the routing configuration will pick. 703 */ 704 nr = fill_local_addresses_vec(msk, &remote, addrs); 705 if (nr == 0) 706 return; 707 708 spin_unlock_bh(&msk->pm.lock); 709 for (i = 0; i < nr; i++) 710 if (__mptcp_subflow_connect(sk, &addrs[i], &remote) == 0) 711 sf_created = true; 712 spin_lock_bh(&msk->pm.lock); 713 714 if (sf_created) { 715 msk->pm.add_addr_accepted++; 716 if (msk->pm.add_addr_accepted >= add_addr_accept_max || 717 msk->pm.subflows >= subflows_max) 718 WRITE_ONCE(msk->pm.accept_addr, false); 719 } 720 } 721 722 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk) 723 { 724 struct mptcp_subflow_context *subflow; 725 726 msk_owned_by_me(msk); 727 lockdep_assert_held(&msk->pm.lock); 728 729 if (!mptcp_pm_should_add_signal(msk) && 730 !mptcp_pm_should_rm_signal(msk)) 731 return; 732 733 subflow = list_first_entry_or_null(&msk->conn_list, typeof(*subflow), node); 734 if (subflow) 735 mptcp_pm_send_ack(msk, subflow, false, false); 736 } 737 738 int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk, 739 struct mptcp_addr_info *addr, 740 struct mptcp_addr_info *rem, 741 u8 bkup) 742 { 743 struct mptcp_subflow_context *subflow; 744 745 pr_debug("bkup=%d", bkup); 746 747 mptcp_for_each_subflow(msk, subflow) { 748 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 749 struct mptcp_addr_info local, remote; 750 751 mptcp_local_address((struct sock_common *)ssk, &local); 752 if (!mptcp_addresses_equal(&local, addr, addr->port)) 753 continue; 754 755 if (rem && rem->family != AF_UNSPEC) { 756 remote_address((struct sock_common *)ssk, &remote); 757 if (!mptcp_addresses_equal(&remote, rem, rem->port)) 758 continue; 759 } 760 761 __mptcp_pm_send_ack(msk, subflow, true, bkup); 762 return 0; 763 } 764 765 return -EINVAL; 766 } 767 768 static bool mptcp_local_id_match(const struct mptcp_sock *msk, u8 local_id, u8 id) 769 { 770 return local_id == id || (!local_id && msk->mpc_endpoint_id == id); 771 } 772 773 static void mptcp_pm_nl_rm_addr_or_subflow(struct mptcp_sock *msk, 774 const struct mptcp_rm_list *rm_list, 775 enum linux_mptcp_mib_field rm_type) 776 { 777 struct mptcp_subflow_context *subflow, *tmp; 778 struct sock *sk = (struct sock *)msk; 779 u8 i; 780 781 pr_debug("%s rm_list_nr %d", 782 rm_type == MPTCP_MIB_RMADDR ? "address" : "subflow", rm_list->nr); 783 784 msk_owned_by_me(msk); 785 786 if (sk->sk_state == TCP_LISTEN) 787 return; 788 789 if (!rm_list->nr) 790 return; 791 792 if (list_empty(&msk->conn_list)) 793 return; 794 795 for (i = 0; i < rm_list->nr; i++) { 796 u8 rm_id = rm_list->ids[i]; 797 bool removed = false; 798 799 mptcp_for_each_subflow_safe(msk, subflow, tmp) { 800 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 801 u8 remote_id = READ_ONCE(subflow->remote_id); 802 int how = RCV_SHUTDOWN | SEND_SHUTDOWN; 803 u8 id = subflow_get_local_id(subflow); 804 805 if (rm_type == MPTCP_MIB_RMADDR && 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, id, remote_id, msk->mpc_endpoint_id); 813 spin_unlock_bh(&msk->pm.lock); 814 mptcp_subflow_shutdown(sk, ssk, how); 815 816 /* the following takes care of updating the subflows counter */ 817 mptcp_close_ssk(sk, ssk, subflow); 818 spin_lock_bh(&msk->pm.lock); 819 820 removed = true; 821 if (rm_type == MPTCP_MIB_RMSUBFLOW) 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 else if (rm_type == MPTCP_MIB_RMADDR) 827 __MPTCP_INC_STATS(sock_net(sk), rm_type); 828 if (!removed) 829 continue; 830 831 if (!mptcp_pm_is_kernel(msk)) 832 continue; 833 834 if (rm_type == MPTCP_MIB_RMADDR) { 835 msk->pm.add_addr_accepted--; 836 WRITE_ONCE(msk->pm.accept_addr, true); 837 } else if (rm_type == MPTCP_MIB_RMSUBFLOW) { 838 msk->pm.local_addr_used--; 839 } 840 } 841 } 842 843 static void mptcp_pm_nl_rm_addr_received(struct mptcp_sock *msk) 844 { 845 mptcp_pm_nl_rm_addr_or_subflow(msk, &msk->pm.rm_list_rx, MPTCP_MIB_RMADDR); 846 } 847 848 void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk, 849 const struct mptcp_rm_list *rm_list) 850 { 851 mptcp_pm_nl_rm_addr_or_subflow(msk, rm_list, MPTCP_MIB_RMSUBFLOW); 852 } 853 854 void mptcp_pm_nl_work(struct mptcp_sock *msk) 855 { 856 struct mptcp_pm_data *pm = &msk->pm; 857 858 msk_owned_by_me(msk); 859 860 if (!(pm->status & MPTCP_PM_WORK_MASK)) 861 return; 862 863 spin_lock_bh(&msk->pm.lock); 864 865 pr_debug("msk=%p status=%x", msk, pm->status); 866 if (pm->status & BIT(MPTCP_PM_ADD_ADDR_RECEIVED)) { 867 pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_RECEIVED); 868 mptcp_pm_nl_add_addr_received(msk); 869 } 870 if (pm->status & BIT(MPTCP_PM_ADD_ADDR_SEND_ACK)) { 871 pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_SEND_ACK); 872 mptcp_pm_nl_addr_send_ack(msk); 873 } 874 if (pm->status & BIT(MPTCP_PM_RM_ADDR_RECEIVED)) { 875 pm->status &= ~BIT(MPTCP_PM_RM_ADDR_RECEIVED); 876 mptcp_pm_nl_rm_addr_received(msk); 877 } 878 if (pm->status & BIT(MPTCP_PM_ESTABLISHED)) { 879 pm->status &= ~BIT(MPTCP_PM_ESTABLISHED); 880 mptcp_pm_nl_fully_established(msk); 881 } 882 if (pm->status & BIT(MPTCP_PM_SUBFLOW_ESTABLISHED)) { 883 pm->status &= ~BIT(MPTCP_PM_SUBFLOW_ESTABLISHED); 884 mptcp_pm_nl_subflow_established(msk); 885 } 886 887 spin_unlock_bh(&msk->pm.lock); 888 } 889 890 static bool address_use_port(struct mptcp_pm_addr_entry *entry) 891 { 892 return (entry->flags & 893 (MPTCP_PM_ADDR_FLAG_SIGNAL | MPTCP_PM_ADDR_FLAG_SUBFLOW)) == 894 MPTCP_PM_ADDR_FLAG_SIGNAL; 895 } 896 897 /* caller must ensure the RCU grace period is already elapsed */ 898 static void __mptcp_pm_release_addr_entry(struct mptcp_pm_addr_entry *entry) 899 { 900 if (entry->lsk) 901 sock_release(entry->lsk); 902 kfree(entry); 903 } 904 905 static int mptcp_pm_nl_append_new_local_addr(struct pm_nl_pernet *pernet, 906 struct mptcp_pm_addr_entry *entry, 907 bool needs_id) 908 { 909 struct mptcp_pm_addr_entry *cur, *del_entry = NULL; 910 unsigned int addr_max; 911 int ret = -EINVAL; 912 913 spin_lock_bh(&pernet->lock); 914 /* to keep the code simple, don't do IDR-like allocation for address ID, 915 * just bail when we exceed limits 916 */ 917 if (pernet->next_id == MPTCP_PM_MAX_ADDR_ID) 918 pernet->next_id = 1; 919 if (pernet->addrs >= MPTCP_PM_ADDR_MAX) { 920 ret = -ERANGE; 921 goto out; 922 } 923 if (test_bit(entry->addr.id, pernet->id_bitmap)) { 924 ret = -EBUSY; 925 goto out; 926 } 927 928 /* do not insert duplicate address, differentiate on port only 929 * singled addresses 930 */ 931 if (!address_use_port(entry)) 932 entry->addr.port = 0; 933 list_for_each_entry(cur, &pernet->local_addr_list, list) { 934 if (mptcp_addresses_equal(&cur->addr, &entry->addr, 935 cur->addr.port || entry->addr.port)) { 936 /* allow replacing the exiting endpoint only if such 937 * endpoint is an implicit one and the user-space 938 * did not provide an endpoint id 939 */ 940 if (!(cur->flags & MPTCP_PM_ADDR_FLAG_IMPLICIT)) { 941 ret = -EEXIST; 942 goto out; 943 } 944 if (entry->addr.id) 945 goto out; 946 947 pernet->addrs--; 948 entry->addr.id = cur->addr.id; 949 list_del_rcu(&cur->list); 950 del_entry = cur; 951 break; 952 } 953 } 954 955 if (!entry->addr.id && needs_id) { 956 find_next: 957 entry->addr.id = find_next_zero_bit(pernet->id_bitmap, 958 MPTCP_PM_MAX_ADDR_ID + 1, 959 pernet->next_id); 960 if (!entry->addr.id && pernet->next_id != 1) { 961 pernet->next_id = 1; 962 goto find_next; 963 } 964 } 965 966 if (!entry->addr.id && needs_id) 967 goto out; 968 969 __set_bit(entry->addr.id, pernet->id_bitmap); 970 if (entry->addr.id > pernet->next_id) 971 pernet->next_id = entry->addr.id; 972 973 if (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL) { 974 addr_max = pernet->add_addr_signal_max; 975 WRITE_ONCE(pernet->add_addr_signal_max, addr_max + 1); 976 } 977 if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) { 978 addr_max = pernet->local_addr_max; 979 WRITE_ONCE(pernet->local_addr_max, addr_max + 1); 980 } 981 982 pernet->addrs++; 983 if (!entry->addr.port) 984 list_add_tail_rcu(&entry->list, &pernet->local_addr_list); 985 else 986 list_add_rcu(&entry->list, &pernet->local_addr_list); 987 ret = entry->addr.id; 988 989 out: 990 spin_unlock_bh(&pernet->lock); 991 992 /* just replaced an existing entry, free it */ 993 if (del_entry) { 994 synchronize_rcu(); 995 __mptcp_pm_release_addr_entry(del_entry); 996 } 997 return ret; 998 } 999 1000 static struct lock_class_key mptcp_slock_keys[2]; 1001 static struct lock_class_key mptcp_keys[2]; 1002 1003 static int mptcp_pm_nl_create_listen_socket(struct sock *sk, 1004 struct mptcp_pm_addr_entry *entry) 1005 { 1006 bool is_ipv6 = sk->sk_family == AF_INET6; 1007 int addrlen = sizeof(struct sockaddr_in); 1008 struct sockaddr_storage addr; 1009 struct sock *newsk, *ssk; 1010 int backlog = 1024; 1011 int err; 1012 1013 err = sock_create_kern(sock_net(sk), entry->addr.family, 1014 SOCK_STREAM, IPPROTO_MPTCP, &entry->lsk); 1015 if (err) 1016 return err; 1017 1018 newsk = entry->lsk->sk; 1019 if (!newsk) 1020 return -EINVAL; 1021 1022 /* The subflow socket lock is acquired in a nested to the msk one 1023 * in several places, even by the TCP stack, and this msk is a kernel 1024 * socket: lockdep complains. Instead of propagating the _nested 1025 * modifiers in several places, re-init the lock class for the msk 1026 * socket to an mptcp specific one. 1027 */ 1028 sock_lock_init_class_and_name(newsk, 1029 is_ipv6 ? "mlock-AF_INET6" : "mlock-AF_INET", 1030 &mptcp_slock_keys[is_ipv6], 1031 is_ipv6 ? "msk_lock-AF_INET6" : "msk_lock-AF_INET", 1032 &mptcp_keys[is_ipv6]); 1033 1034 lock_sock(newsk); 1035 ssk = __mptcp_nmpc_sk(mptcp_sk(newsk)); 1036 release_sock(newsk); 1037 if (IS_ERR(ssk)) 1038 return PTR_ERR(ssk); 1039 1040 mptcp_info2sockaddr(&entry->addr, &addr, entry->addr.family); 1041 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1042 if (entry->addr.family == AF_INET6) 1043 addrlen = sizeof(struct sockaddr_in6); 1044 #endif 1045 if (ssk->sk_family == AF_INET) 1046 err = inet_bind_sk(ssk, (struct sockaddr *)&addr, addrlen); 1047 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1048 else if (ssk->sk_family == AF_INET6) 1049 err = inet6_bind_sk(ssk, (struct sockaddr *)&addr, addrlen); 1050 #endif 1051 if (err) 1052 return err; 1053 1054 /* We don't use mptcp_set_state() here because it needs to be called 1055 * under the msk socket lock. For the moment, that will not bring 1056 * anything more than only calling inet_sk_state_store(), because the 1057 * old status is known (TCP_CLOSE). 1058 */ 1059 inet_sk_state_store(newsk, TCP_LISTEN); 1060 lock_sock(ssk); 1061 err = __inet_listen_sk(ssk, backlog); 1062 if (!err) 1063 mptcp_event_pm_listener(ssk, MPTCP_EVENT_LISTENER_CREATED); 1064 release_sock(ssk); 1065 return err; 1066 } 1067 1068 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc) 1069 { 1070 struct mptcp_pm_addr_entry *entry; 1071 struct pm_nl_pernet *pernet; 1072 int ret = -1; 1073 1074 pernet = pm_nl_get_pernet_from_msk(msk); 1075 1076 rcu_read_lock(); 1077 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 1078 if (mptcp_addresses_equal(&entry->addr, skc, entry->addr.port)) { 1079 ret = entry->addr.id; 1080 break; 1081 } 1082 } 1083 rcu_read_unlock(); 1084 if (ret >= 0) 1085 return ret; 1086 1087 /* address not found, add to local list */ 1088 entry = kmalloc(sizeof(*entry), GFP_ATOMIC); 1089 if (!entry) 1090 return -ENOMEM; 1091 1092 entry->addr = *skc; 1093 entry->addr.id = 0; 1094 entry->addr.port = 0; 1095 entry->ifindex = 0; 1096 entry->flags = MPTCP_PM_ADDR_FLAG_IMPLICIT; 1097 entry->lsk = NULL; 1098 ret = mptcp_pm_nl_append_new_local_addr(pernet, entry, true); 1099 if (ret < 0) 1100 kfree(entry); 1101 1102 return ret; 1103 } 1104 1105 #define MPTCP_PM_CMD_GRP_OFFSET 0 1106 #define MPTCP_PM_EV_GRP_OFFSET 1 1107 1108 static const struct genl_multicast_group mptcp_pm_mcgrps[] = { 1109 [MPTCP_PM_CMD_GRP_OFFSET] = { .name = MPTCP_PM_CMD_GRP_NAME, }, 1110 [MPTCP_PM_EV_GRP_OFFSET] = { .name = MPTCP_PM_EV_GRP_NAME, 1111 .flags = GENL_MCAST_CAP_NET_ADMIN, 1112 }, 1113 }; 1114 1115 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk) 1116 { 1117 struct mptcp_subflow_context *iter, *subflow = mptcp_subflow_ctx(ssk); 1118 struct sock *sk = (struct sock *)msk; 1119 unsigned int active_max_loss_cnt; 1120 struct net *net = sock_net(sk); 1121 unsigned int stale_loss_cnt; 1122 bool slow; 1123 1124 stale_loss_cnt = mptcp_stale_loss_cnt(net); 1125 if (subflow->stale || !stale_loss_cnt || subflow->stale_count <= stale_loss_cnt) 1126 return; 1127 1128 /* look for another available subflow not in loss state */ 1129 active_max_loss_cnt = max_t(int, stale_loss_cnt - 1, 1); 1130 mptcp_for_each_subflow(msk, iter) { 1131 if (iter != subflow && mptcp_subflow_active(iter) && 1132 iter->stale_count < active_max_loss_cnt) { 1133 /* we have some alternatives, try to mark this subflow as idle ...*/ 1134 slow = lock_sock_fast(ssk); 1135 if (!tcp_rtx_and_write_queues_empty(ssk)) { 1136 subflow->stale = 1; 1137 __mptcp_retransmit_pending_data(sk); 1138 MPTCP_INC_STATS(net, MPTCP_MIB_SUBFLOWSTALE); 1139 } 1140 unlock_sock_fast(ssk, slow); 1141 1142 /* always try to push the pending data regardless of re-injections: 1143 * we can possibly use backup subflows now, and subflow selection 1144 * is cheap under the msk socket lock 1145 */ 1146 __mptcp_push_pending(sk, 0); 1147 return; 1148 } 1149 } 1150 } 1151 1152 static int mptcp_pm_family_to_addr(int family) 1153 { 1154 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1155 if (family == AF_INET6) 1156 return MPTCP_PM_ADDR_ATTR_ADDR6; 1157 #endif 1158 return MPTCP_PM_ADDR_ATTR_ADDR4; 1159 } 1160 1161 static int mptcp_pm_parse_pm_addr_attr(struct nlattr *tb[], 1162 const struct nlattr *attr, 1163 struct genl_info *info, 1164 struct mptcp_addr_info *addr, 1165 bool require_family) 1166 { 1167 int err, addr_addr; 1168 1169 if (!attr) { 1170 GENL_SET_ERR_MSG(info, "missing address info"); 1171 return -EINVAL; 1172 } 1173 1174 /* no validation needed - was already done via nested policy */ 1175 err = nla_parse_nested_deprecated(tb, MPTCP_PM_ADDR_ATTR_MAX, attr, 1176 mptcp_pm_address_nl_policy, info->extack); 1177 if (err) 1178 return err; 1179 1180 if (tb[MPTCP_PM_ADDR_ATTR_ID]) 1181 addr->id = nla_get_u8(tb[MPTCP_PM_ADDR_ATTR_ID]); 1182 1183 if (!tb[MPTCP_PM_ADDR_ATTR_FAMILY]) { 1184 if (!require_family) 1185 return 0; 1186 1187 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1188 "missing family"); 1189 return -EINVAL; 1190 } 1191 1192 addr->family = nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_FAMILY]); 1193 if (addr->family != AF_INET 1194 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1195 && addr->family != AF_INET6 1196 #endif 1197 ) { 1198 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1199 "unknown address family"); 1200 return -EINVAL; 1201 } 1202 addr_addr = mptcp_pm_family_to_addr(addr->family); 1203 if (!tb[addr_addr]) { 1204 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1205 "missing address data"); 1206 return -EINVAL; 1207 } 1208 1209 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1210 if (addr->family == AF_INET6) 1211 addr->addr6 = nla_get_in6_addr(tb[addr_addr]); 1212 else 1213 #endif 1214 addr->addr.s_addr = nla_get_in_addr(tb[addr_addr]); 1215 1216 if (tb[MPTCP_PM_ADDR_ATTR_PORT]) 1217 addr->port = htons(nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_PORT])); 1218 1219 return 0; 1220 } 1221 1222 int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info, 1223 struct mptcp_addr_info *addr) 1224 { 1225 struct nlattr *tb[MPTCP_PM_ADDR_ATTR_MAX + 1]; 1226 1227 memset(addr, 0, sizeof(*addr)); 1228 1229 return mptcp_pm_parse_pm_addr_attr(tb, attr, info, addr, true); 1230 } 1231 1232 int mptcp_pm_parse_entry(struct nlattr *attr, struct genl_info *info, 1233 bool require_family, 1234 struct mptcp_pm_addr_entry *entry) 1235 { 1236 struct nlattr *tb[MPTCP_PM_ADDR_ATTR_MAX + 1]; 1237 int err; 1238 1239 memset(entry, 0, sizeof(*entry)); 1240 1241 err = mptcp_pm_parse_pm_addr_attr(tb, attr, info, &entry->addr, require_family); 1242 if (err) 1243 return err; 1244 1245 if (tb[MPTCP_PM_ADDR_ATTR_IF_IDX]) { 1246 u32 val = nla_get_s32(tb[MPTCP_PM_ADDR_ATTR_IF_IDX]); 1247 1248 entry->ifindex = val; 1249 } 1250 1251 if (tb[MPTCP_PM_ADDR_ATTR_FLAGS]) 1252 entry->flags = nla_get_u32(tb[MPTCP_PM_ADDR_ATTR_FLAGS]); 1253 1254 if (tb[MPTCP_PM_ADDR_ATTR_PORT]) 1255 entry->addr.port = htons(nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_PORT])); 1256 1257 return 0; 1258 } 1259 1260 static struct pm_nl_pernet *genl_info_pm_nl(struct genl_info *info) 1261 { 1262 return pm_nl_get_pernet(genl_info_net(info)); 1263 } 1264 1265 static int mptcp_nl_add_subflow_or_signal_addr(struct net *net) 1266 { 1267 struct mptcp_sock *msk; 1268 long s_slot = 0, s_num = 0; 1269 1270 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1271 struct sock *sk = (struct sock *)msk; 1272 1273 if (!READ_ONCE(msk->fully_established) || 1274 mptcp_pm_is_userspace(msk)) 1275 goto next; 1276 1277 lock_sock(sk); 1278 spin_lock_bh(&msk->pm.lock); 1279 mptcp_pm_create_subflow_or_signal_addr(msk); 1280 spin_unlock_bh(&msk->pm.lock); 1281 release_sock(sk); 1282 1283 next: 1284 sock_put(sk); 1285 cond_resched(); 1286 } 1287 1288 return 0; 1289 } 1290 1291 static bool mptcp_pm_has_addr_attr_id(const struct nlattr *attr, 1292 struct genl_info *info) 1293 { 1294 struct nlattr *tb[MPTCP_PM_ADDR_ATTR_MAX + 1]; 1295 1296 if (!nla_parse_nested_deprecated(tb, MPTCP_PM_ADDR_ATTR_MAX, attr, 1297 mptcp_pm_address_nl_policy, info->extack) && 1298 tb[MPTCP_PM_ADDR_ATTR_ID]) 1299 return true; 1300 return false; 1301 } 1302 1303 int mptcp_pm_nl_add_addr_doit(struct sk_buff *skb, struct genl_info *info) 1304 { 1305 struct nlattr *attr = info->attrs[MPTCP_PM_ENDPOINT_ADDR]; 1306 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1307 struct mptcp_pm_addr_entry addr, *entry; 1308 int ret; 1309 1310 ret = mptcp_pm_parse_entry(attr, info, true, &addr); 1311 if (ret < 0) 1312 return ret; 1313 1314 if (addr.addr.port && !(addr.flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) { 1315 GENL_SET_ERR_MSG(info, "flags must have signal when using port"); 1316 return -EINVAL; 1317 } 1318 1319 if (addr.flags & MPTCP_PM_ADDR_FLAG_SIGNAL && 1320 addr.flags & MPTCP_PM_ADDR_FLAG_FULLMESH) { 1321 GENL_SET_ERR_MSG(info, "flags mustn't have both signal and fullmesh"); 1322 return -EINVAL; 1323 } 1324 1325 if (addr.flags & MPTCP_PM_ADDR_FLAG_IMPLICIT) { 1326 GENL_SET_ERR_MSG(info, "can't create IMPLICIT endpoint"); 1327 return -EINVAL; 1328 } 1329 1330 entry = kzalloc(sizeof(*entry), GFP_KERNEL_ACCOUNT); 1331 if (!entry) { 1332 GENL_SET_ERR_MSG(info, "can't allocate addr"); 1333 return -ENOMEM; 1334 } 1335 1336 *entry = addr; 1337 if (entry->addr.port) { 1338 ret = mptcp_pm_nl_create_listen_socket(skb->sk, entry); 1339 if (ret) { 1340 GENL_SET_ERR_MSG_FMT(info, "create listen socket error: %d", ret); 1341 goto out_free; 1342 } 1343 } 1344 ret = mptcp_pm_nl_append_new_local_addr(pernet, entry, 1345 !mptcp_pm_has_addr_attr_id(attr, info)); 1346 if (ret < 0) { 1347 GENL_SET_ERR_MSG_FMT(info, "too many addresses or duplicate one: %d", ret); 1348 goto out_free; 1349 } 1350 1351 mptcp_nl_add_subflow_or_signal_addr(sock_net(skb->sk)); 1352 return 0; 1353 1354 out_free: 1355 __mptcp_pm_release_addr_entry(entry); 1356 return ret; 1357 } 1358 1359 int mptcp_pm_nl_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, unsigned int id, 1360 u8 *flags, int *ifindex) 1361 { 1362 struct mptcp_pm_addr_entry *entry; 1363 struct sock *sk = (struct sock *)msk; 1364 struct net *net = sock_net(sk); 1365 1366 rcu_read_lock(); 1367 entry = __lookup_addr_by_id(pm_nl_get_pernet(net), id); 1368 if (entry) { 1369 *flags = entry->flags; 1370 *ifindex = entry->ifindex; 1371 } 1372 rcu_read_unlock(); 1373 1374 return 0; 1375 } 1376 1377 static bool remove_anno_list_by_saddr(struct mptcp_sock *msk, 1378 const struct mptcp_addr_info *addr) 1379 { 1380 struct mptcp_pm_add_entry *entry; 1381 1382 entry = mptcp_pm_del_add_timer(msk, addr, false); 1383 if (entry) { 1384 list_del(&entry->list); 1385 kfree(entry); 1386 return true; 1387 } 1388 1389 return false; 1390 } 1391 1392 static bool mptcp_pm_remove_anno_addr(struct mptcp_sock *msk, 1393 const struct mptcp_addr_info *addr, 1394 bool force) 1395 { 1396 struct mptcp_rm_list list = { .nr = 0 }; 1397 bool ret; 1398 1399 list.ids[list.nr++] = addr->id; 1400 1401 ret = remove_anno_list_by_saddr(msk, addr); 1402 if (ret || force) { 1403 spin_lock_bh(&msk->pm.lock); 1404 mptcp_pm_remove_addr(msk, &list); 1405 spin_unlock_bh(&msk->pm.lock); 1406 } 1407 return ret; 1408 } 1409 1410 static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net, 1411 const struct mptcp_pm_addr_entry *entry) 1412 { 1413 const struct mptcp_addr_info *addr = &entry->addr; 1414 struct mptcp_rm_list list = { .nr = 0 }; 1415 long s_slot = 0, s_num = 0; 1416 struct mptcp_sock *msk; 1417 1418 pr_debug("remove_id=%d", addr->id); 1419 1420 list.ids[list.nr++] = addr->id; 1421 1422 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1423 struct sock *sk = (struct sock *)msk; 1424 bool remove_subflow; 1425 1426 if (mptcp_pm_is_userspace(msk)) 1427 goto next; 1428 1429 if (list_empty(&msk->conn_list)) { 1430 mptcp_pm_remove_anno_addr(msk, addr, false); 1431 goto next; 1432 } 1433 1434 lock_sock(sk); 1435 remove_subflow = lookup_subflow_by_saddr(&msk->conn_list, addr); 1436 mptcp_pm_remove_anno_addr(msk, addr, remove_subflow && 1437 !(entry->flags & MPTCP_PM_ADDR_FLAG_IMPLICIT)); 1438 if (remove_subflow) 1439 mptcp_pm_remove_subflow(msk, &list); 1440 release_sock(sk); 1441 1442 next: 1443 sock_put(sk); 1444 cond_resched(); 1445 } 1446 1447 return 0; 1448 } 1449 1450 static int mptcp_nl_remove_id_zero_address(struct net *net, 1451 struct mptcp_addr_info *addr) 1452 { 1453 struct mptcp_rm_list list = { .nr = 0 }; 1454 long s_slot = 0, s_num = 0; 1455 struct mptcp_sock *msk; 1456 1457 list.ids[list.nr++] = 0; 1458 1459 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1460 struct sock *sk = (struct sock *)msk; 1461 struct mptcp_addr_info msk_local; 1462 1463 if (list_empty(&msk->conn_list) || mptcp_pm_is_userspace(msk)) 1464 goto next; 1465 1466 mptcp_local_address((struct sock_common *)msk, &msk_local); 1467 if (!mptcp_addresses_equal(&msk_local, addr, addr->port)) 1468 goto next; 1469 1470 lock_sock(sk); 1471 spin_lock_bh(&msk->pm.lock); 1472 mptcp_pm_remove_addr(msk, &list); 1473 mptcp_pm_nl_rm_subflow_received(msk, &list); 1474 spin_unlock_bh(&msk->pm.lock); 1475 release_sock(sk); 1476 1477 next: 1478 sock_put(sk); 1479 cond_resched(); 1480 } 1481 1482 return 0; 1483 } 1484 1485 int mptcp_pm_nl_del_addr_doit(struct sk_buff *skb, struct genl_info *info) 1486 { 1487 struct nlattr *attr = info->attrs[MPTCP_PM_ENDPOINT_ADDR]; 1488 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1489 struct mptcp_pm_addr_entry addr, *entry; 1490 unsigned int addr_max; 1491 int ret; 1492 1493 ret = mptcp_pm_parse_entry(attr, info, false, &addr); 1494 if (ret < 0) 1495 return ret; 1496 1497 /* the zero id address is special: the first address used by the msk 1498 * always gets such an id, so different subflows can have different zero 1499 * id addresses. Additionally zero id is not accounted for in id_bitmap. 1500 * Let's use an 'mptcp_rm_list' instead of the common remove code. 1501 */ 1502 if (addr.addr.id == 0) 1503 return mptcp_nl_remove_id_zero_address(sock_net(skb->sk), &addr.addr); 1504 1505 spin_lock_bh(&pernet->lock); 1506 entry = __lookup_addr_by_id(pernet, addr.addr.id); 1507 if (!entry) { 1508 GENL_SET_ERR_MSG(info, "address not found"); 1509 spin_unlock_bh(&pernet->lock); 1510 return -EINVAL; 1511 } 1512 if (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL) { 1513 addr_max = pernet->add_addr_signal_max; 1514 WRITE_ONCE(pernet->add_addr_signal_max, addr_max - 1); 1515 } 1516 if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) { 1517 addr_max = pernet->local_addr_max; 1518 WRITE_ONCE(pernet->local_addr_max, addr_max - 1); 1519 } 1520 1521 pernet->addrs--; 1522 list_del_rcu(&entry->list); 1523 __clear_bit(entry->addr.id, pernet->id_bitmap); 1524 spin_unlock_bh(&pernet->lock); 1525 1526 mptcp_nl_remove_subflow_and_signal_addr(sock_net(skb->sk), entry); 1527 synchronize_rcu(); 1528 __mptcp_pm_release_addr_entry(entry); 1529 1530 return ret; 1531 } 1532 1533 void mptcp_pm_remove_addrs(struct mptcp_sock *msk, struct list_head *rm_list) 1534 { 1535 struct mptcp_rm_list alist = { .nr = 0 }; 1536 struct mptcp_pm_addr_entry *entry; 1537 1538 list_for_each_entry(entry, rm_list, list) { 1539 if ((remove_anno_list_by_saddr(msk, &entry->addr) || 1540 lookup_subflow_by_saddr(&msk->conn_list, &entry->addr)) && 1541 alist.nr < MPTCP_RM_IDS_MAX) 1542 alist.ids[alist.nr++] = entry->addr.id; 1543 } 1544 1545 if (alist.nr) { 1546 spin_lock_bh(&msk->pm.lock); 1547 mptcp_pm_remove_addr(msk, &alist); 1548 spin_unlock_bh(&msk->pm.lock); 1549 } 1550 } 1551 1552 static void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk, 1553 struct list_head *rm_list) 1554 { 1555 struct mptcp_rm_list alist = { .nr = 0 }, slist = { .nr = 0 }; 1556 struct mptcp_pm_addr_entry *entry; 1557 1558 list_for_each_entry(entry, rm_list, list) { 1559 if (lookup_subflow_by_saddr(&msk->conn_list, &entry->addr) && 1560 slist.nr < MPTCP_RM_IDS_MAX) 1561 slist.ids[slist.nr++] = entry->addr.id; 1562 1563 if (remove_anno_list_by_saddr(msk, &entry->addr) && 1564 alist.nr < MPTCP_RM_IDS_MAX) 1565 alist.ids[alist.nr++] = entry->addr.id; 1566 } 1567 1568 if (alist.nr) { 1569 spin_lock_bh(&msk->pm.lock); 1570 mptcp_pm_remove_addr(msk, &alist); 1571 spin_unlock_bh(&msk->pm.lock); 1572 } 1573 if (slist.nr) 1574 mptcp_pm_remove_subflow(msk, &slist); 1575 } 1576 1577 static void mptcp_nl_remove_addrs_list(struct net *net, 1578 struct list_head *rm_list) 1579 { 1580 long s_slot = 0, s_num = 0; 1581 struct mptcp_sock *msk; 1582 1583 if (list_empty(rm_list)) 1584 return; 1585 1586 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1587 struct sock *sk = (struct sock *)msk; 1588 1589 if (!mptcp_pm_is_userspace(msk)) { 1590 lock_sock(sk); 1591 mptcp_pm_remove_addrs_and_subflows(msk, rm_list); 1592 release_sock(sk); 1593 } 1594 1595 sock_put(sk); 1596 cond_resched(); 1597 } 1598 } 1599 1600 /* caller must ensure the RCU grace period is already elapsed */ 1601 static void __flush_addrs(struct list_head *list) 1602 { 1603 while (!list_empty(list)) { 1604 struct mptcp_pm_addr_entry *cur; 1605 1606 cur = list_entry(list->next, 1607 struct mptcp_pm_addr_entry, list); 1608 list_del_rcu(&cur->list); 1609 __mptcp_pm_release_addr_entry(cur); 1610 } 1611 } 1612 1613 static void __reset_counters(struct pm_nl_pernet *pernet) 1614 { 1615 WRITE_ONCE(pernet->add_addr_signal_max, 0); 1616 WRITE_ONCE(pernet->add_addr_accept_max, 0); 1617 WRITE_ONCE(pernet->local_addr_max, 0); 1618 pernet->addrs = 0; 1619 } 1620 1621 int mptcp_pm_nl_flush_addrs_doit(struct sk_buff *skb, struct genl_info *info) 1622 { 1623 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1624 LIST_HEAD(free_list); 1625 1626 spin_lock_bh(&pernet->lock); 1627 list_splice_init(&pernet->local_addr_list, &free_list); 1628 __reset_counters(pernet); 1629 pernet->next_id = 1; 1630 bitmap_zero(pernet->id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); 1631 spin_unlock_bh(&pernet->lock); 1632 mptcp_nl_remove_addrs_list(sock_net(skb->sk), &free_list); 1633 synchronize_rcu(); 1634 __flush_addrs(&free_list); 1635 return 0; 1636 } 1637 1638 int mptcp_nl_fill_addr(struct sk_buff *skb, 1639 struct mptcp_pm_addr_entry *entry) 1640 { 1641 struct mptcp_addr_info *addr = &entry->addr; 1642 struct nlattr *attr; 1643 1644 attr = nla_nest_start(skb, MPTCP_PM_ATTR_ADDR); 1645 if (!attr) 1646 return -EMSGSIZE; 1647 1648 if (nla_put_u16(skb, MPTCP_PM_ADDR_ATTR_FAMILY, addr->family)) 1649 goto nla_put_failure; 1650 if (nla_put_u16(skb, MPTCP_PM_ADDR_ATTR_PORT, ntohs(addr->port))) 1651 goto nla_put_failure; 1652 if (nla_put_u8(skb, MPTCP_PM_ADDR_ATTR_ID, addr->id)) 1653 goto nla_put_failure; 1654 if (nla_put_u32(skb, MPTCP_PM_ADDR_ATTR_FLAGS, entry->flags)) 1655 goto nla_put_failure; 1656 if (entry->ifindex && 1657 nla_put_s32(skb, MPTCP_PM_ADDR_ATTR_IF_IDX, entry->ifindex)) 1658 goto nla_put_failure; 1659 1660 if (addr->family == AF_INET && 1661 nla_put_in_addr(skb, MPTCP_PM_ADDR_ATTR_ADDR4, 1662 addr->addr.s_addr)) 1663 goto nla_put_failure; 1664 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1665 else if (addr->family == AF_INET6 && 1666 nla_put_in6_addr(skb, MPTCP_PM_ADDR_ATTR_ADDR6, &addr->addr6)) 1667 goto nla_put_failure; 1668 #endif 1669 nla_nest_end(skb, attr); 1670 return 0; 1671 1672 nla_put_failure: 1673 nla_nest_cancel(skb, attr); 1674 return -EMSGSIZE; 1675 } 1676 1677 int mptcp_pm_nl_get_addr(struct sk_buff *skb, struct genl_info *info) 1678 { 1679 struct nlattr *attr = info->attrs[MPTCP_PM_ENDPOINT_ADDR]; 1680 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1681 struct mptcp_pm_addr_entry addr, *entry; 1682 struct sk_buff *msg; 1683 void *reply; 1684 int ret; 1685 1686 ret = mptcp_pm_parse_entry(attr, info, false, &addr); 1687 if (ret < 0) 1688 return ret; 1689 1690 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 1691 if (!msg) 1692 return -ENOMEM; 1693 1694 reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0, 1695 info->genlhdr->cmd); 1696 if (!reply) { 1697 GENL_SET_ERR_MSG(info, "not enough space in Netlink message"); 1698 ret = -EMSGSIZE; 1699 goto fail; 1700 } 1701 1702 spin_lock_bh(&pernet->lock); 1703 entry = __lookup_addr_by_id(pernet, addr.addr.id); 1704 if (!entry) { 1705 GENL_SET_ERR_MSG(info, "address not found"); 1706 ret = -EINVAL; 1707 goto unlock_fail; 1708 } 1709 1710 ret = mptcp_nl_fill_addr(msg, entry); 1711 if (ret) 1712 goto unlock_fail; 1713 1714 genlmsg_end(msg, reply); 1715 ret = genlmsg_reply(msg, info); 1716 spin_unlock_bh(&pernet->lock); 1717 return ret; 1718 1719 unlock_fail: 1720 spin_unlock_bh(&pernet->lock); 1721 1722 fail: 1723 nlmsg_free(msg); 1724 return ret; 1725 } 1726 1727 int mptcp_pm_nl_get_addr_doit(struct sk_buff *skb, struct genl_info *info) 1728 { 1729 return mptcp_pm_get_addr(skb, info); 1730 } 1731 1732 int mptcp_pm_nl_dump_addr(struct sk_buff *msg, 1733 struct netlink_callback *cb) 1734 { 1735 struct net *net = sock_net(msg->sk); 1736 struct mptcp_pm_addr_entry *entry; 1737 struct pm_nl_pernet *pernet; 1738 int id = cb->args[0]; 1739 void *hdr; 1740 int i; 1741 1742 pernet = pm_nl_get_pernet(net); 1743 1744 spin_lock_bh(&pernet->lock); 1745 for (i = id; i < MPTCP_PM_MAX_ADDR_ID + 1; i++) { 1746 if (test_bit(i, pernet->id_bitmap)) { 1747 entry = __lookup_addr_by_id(pernet, i); 1748 if (!entry) 1749 break; 1750 1751 if (entry->addr.id <= id) 1752 continue; 1753 1754 hdr = genlmsg_put(msg, NETLINK_CB(cb->skb).portid, 1755 cb->nlh->nlmsg_seq, &mptcp_genl_family, 1756 NLM_F_MULTI, MPTCP_PM_CMD_GET_ADDR); 1757 if (!hdr) 1758 break; 1759 1760 if (mptcp_nl_fill_addr(msg, entry) < 0) { 1761 genlmsg_cancel(msg, hdr); 1762 break; 1763 } 1764 1765 id = entry->addr.id; 1766 genlmsg_end(msg, hdr); 1767 } 1768 } 1769 spin_unlock_bh(&pernet->lock); 1770 1771 cb->args[0] = id; 1772 return msg->len; 1773 } 1774 1775 int mptcp_pm_nl_get_addr_dumpit(struct sk_buff *msg, 1776 struct netlink_callback *cb) 1777 { 1778 return mptcp_pm_dump_addr(msg, cb); 1779 } 1780 1781 static int parse_limit(struct genl_info *info, int id, unsigned int *limit) 1782 { 1783 struct nlattr *attr = info->attrs[id]; 1784 1785 if (!attr) 1786 return 0; 1787 1788 *limit = nla_get_u32(attr); 1789 if (*limit > MPTCP_PM_ADDR_MAX) { 1790 GENL_SET_ERR_MSG(info, "limit greater than maximum"); 1791 return -EINVAL; 1792 } 1793 return 0; 1794 } 1795 1796 int mptcp_pm_nl_set_limits_doit(struct sk_buff *skb, struct genl_info *info) 1797 { 1798 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1799 unsigned int rcv_addrs, subflows; 1800 int ret; 1801 1802 spin_lock_bh(&pernet->lock); 1803 rcv_addrs = pernet->add_addr_accept_max; 1804 ret = parse_limit(info, MPTCP_PM_ATTR_RCV_ADD_ADDRS, &rcv_addrs); 1805 if (ret) 1806 goto unlock; 1807 1808 subflows = pernet->subflows_max; 1809 ret = parse_limit(info, MPTCP_PM_ATTR_SUBFLOWS, &subflows); 1810 if (ret) 1811 goto unlock; 1812 1813 WRITE_ONCE(pernet->add_addr_accept_max, rcv_addrs); 1814 WRITE_ONCE(pernet->subflows_max, subflows); 1815 1816 unlock: 1817 spin_unlock_bh(&pernet->lock); 1818 return ret; 1819 } 1820 1821 int mptcp_pm_nl_get_limits_doit(struct sk_buff *skb, struct genl_info *info) 1822 { 1823 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1824 struct sk_buff *msg; 1825 void *reply; 1826 1827 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 1828 if (!msg) 1829 return -ENOMEM; 1830 1831 reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0, 1832 MPTCP_PM_CMD_GET_LIMITS); 1833 if (!reply) 1834 goto fail; 1835 1836 if (nla_put_u32(msg, MPTCP_PM_ATTR_RCV_ADD_ADDRS, 1837 READ_ONCE(pernet->add_addr_accept_max))) 1838 goto fail; 1839 1840 if (nla_put_u32(msg, MPTCP_PM_ATTR_SUBFLOWS, 1841 READ_ONCE(pernet->subflows_max))) 1842 goto fail; 1843 1844 genlmsg_end(msg, reply); 1845 return genlmsg_reply(msg, info); 1846 1847 fail: 1848 GENL_SET_ERR_MSG(info, "not enough space in Netlink message"); 1849 nlmsg_free(msg); 1850 return -EMSGSIZE; 1851 } 1852 1853 static void mptcp_pm_nl_fullmesh(struct mptcp_sock *msk, 1854 struct mptcp_addr_info *addr) 1855 { 1856 struct mptcp_rm_list list = { .nr = 0 }; 1857 1858 list.ids[list.nr++] = addr->id; 1859 1860 spin_lock_bh(&msk->pm.lock); 1861 mptcp_pm_nl_rm_subflow_received(msk, &list); 1862 mptcp_pm_create_subflow_or_signal_addr(msk); 1863 spin_unlock_bh(&msk->pm.lock); 1864 } 1865 1866 static int mptcp_nl_set_flags(struct net *net, 1867 struct mptcp_addr_info *addr, 1868 u8 bkup, u8 changed) 1869 { 1870 long s_slot = 0, s_num = 0; 1871 struct mptcp_sock *msk; 1872 int ret = -EINVAL; 1873 1874 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1875 struct sock *sk = (struct sock *)msk; 1876 1877 if (list_empty(&msk->conn_list) || mptcp_pm_is_userspace(msk)) 1878 goto next; 1879 1880 lock_sock(sk); 1881 if (changed & MPTCP_PM_ADDR_FLAG_BACKUP) 1882 ret = mptcp_pm_nl_mp_prio_send_ack(msk, addr, NULL, bkup); 1883 if (changed & MPTCP_PM_ADDR_FLAG_FULLMESH) 1884 mptcp_pm_nl_fullmesh(msk, addr); 1885 release_sock(sk); 1886 1887 next: 1888 sock_put(sk); 1889 cond_resched(); 1890 } 1891 1892 return ret; 1893 } 1894 1895 int mptcp_pm_nl_set_flags(struct sk_buff *skb, struct genl_info *info) 1896 { 1897 struct mptcp_pm_addr_entry addr = { .addr = { .family = AF_UNSPEC }, }; 1898 struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR]; 1899 u8 changed, mask = MPTCP_PM_ADDR_FLAG_BACKUP | 1900 MPTCP_PM_ADDR_FLAG_FULLMESH; 1901 struct net *net = sock_net(skb->sk); 1902 struct mptcp_pm_addr_entry *entry; 1903 struct pm_nl_pernet *pernet; 1904 u8 lookup_by_id = 0; 1905 u8 bkup = 0; 1906 int ret; 1907 1908 pernet = pm_nl_get_pernet(net); 1909 1910 ret = mptcp_pm_parse_entry(attr, info, false, &addr); 1911 if (ret < 0) 1912 return ret; 1913 1914 if (addr.addr.family == AF_UNSPEC) { 1915 lookup_by_id = 1; 1916 if (!addr.addr.id) { 1917 GENL_SET_ERR_MSG(info, "missing required inputs"); 1918 return -EOPNOTSUPP; 1919 } 1920 } 1921 1922 if (addr.flags & MPTCP_PM_ADDR_FLAG_BACKUP) 1923 bkup = 1; 1924 1925 spin_lock_bh(&pernet->lock); 1926 entry = lookup_by_id ? __lookup_addr_by_id(pernet, addr.addr.id) : 1927 __lookup_addr(pernet, &addr.addr); 1928 if (!entry) { 1929 spin_unlock_bh(&pernet->lock); 1930 GENL_SET_ERR_MSG(info, "address not found"); 1931 return -EINVAL; 1932 } 1933 if ((addr.flags & MPTCP_PM_ADDR_FLAG_FULLMESH) && 1934 (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) { 1935 spin_unlock_bh(&pernet->lock); 1936 GENL_SET_ERR_MSG(info, "invalid addr flags"); 1937 return -EINVAL; 1938 } 1939 1940 changed = (addr.flags ^ entry->flags) & mask; 1941 entry->flags = (entry->flags & ~mask) | (addr.flags & mask); 1942 addr = *entry; 1943 spin_unlock_bh(&pernet->lock); 1944 1945 mptcp_nl_set_flags(net, &addr.addr, bkup, changed); 1946 return 0; 1947 } 1948 1949 int mptcp_pm_nl_set_flags_doit(struct sk_buff *skb, struct genl_info *info) 1950 { 1951 return mptcp_pm_set_flags(skb, info); 1952 } 1953 1954 static void mptcp_nl_mcast_send(struct net *net, struct sk_buff *nlskb, gfp_t gfp) 1955 { 1956 genlmsg_multicast_netns(&mptcp_genl_family, net, 1957 nlskb, 0, MPTCP_PM_EV_GRP_OFFSET, gfp); 1958 } 1959 1960 bool mptcp_userspace_pm_active(const struct mptcp_sock *msk) 1961 { 1962 return genl_has_listeners(&mptcp_genl_family, 1963 sock_net((const struct sock *)msk), 1964 MPTCP_PM_EV_GRP_OFFSET); 1965 } 1966 1967 static int mptcp_event_add_subflow(struct sk_buff *skb, const struct sock *ssk) 1968 { 1969 const struct inet_sock *issk = inet_sk(ssk); 1970 const struct mptcp_subflow_context *sf; 1971 1972 if (nla_put_u16(skb, MPTCP_ATTR_FAMILY, ssk->sk_family)) 1973 return -EMSGSIZE; 1974 1975 switch (ssk->sk_family) { 1976 case AF_INET: 1977 if (nla_put_in_addr(skb, MPTCP_ATTR_SADDR4, issk->inet_saddr)) 1978 return -EMSGSIZE; 1979 if (nla_put_in_addr(skb, MPTCP_ATTR_DADDR4, issk->inet_daddr)) 1980 return -EMSGSIZE; 1981 break; 1982 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1983 case AF_INET6: { 1984 const struct ipv6_pinfo *np = inet6_sk(ssk); 1985 1986 if (nla_put_in6_addr(skb, MPTCP_ATTR_SADDR6, &np->saddr)) 1987 return -EMSGSIZE; 1988 if (nla_put_in6_addr(skb, MPTCP_ATTR_DADDR6, &ssk->sk_v6_daddr)) 1989 return -EMSGSIZE; 1990 break; 1991 } 1992 #endif 1993 default: 1994 WARN_ON_ONCE(1); 1995 return -EMSGSIZE; 1996 } 1997 1998 if (nla_put_be16(skb, MPTCP_ATTR_SPORT, issk->inet_sport)) 1999 return -EMSGSIZE; 2000 if (nla_put_be16(skb, MPTCP_ATTR_DPORT, issk->inet_dport)) 2001 return -EMSGSIZE; 2002 2003 sf = mptcp_subflow_ctx(ssk); 2004 if (WARN_ON_ONCE(!sf)) 2005 return -EINVAL; 2006 2007 if (nla_put_u8(skb, MPTCP_ATTR_LOC_ID, subflow_get_local_id(sf))) 2008 return -EMSGSIZE; 2009 2010 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, sf->remote_id)) 2011 return -EMSGSIZE; 2012 2013 return 0; 2014 } 2015 2016 static int mptcp_event_put_token_and_ssk(struct sk_buff *skb, 2017 const struct mptcp_sock *msk, 2018 const struct sock *ssk) 2019 { 2020 const struct sock *sk = (const struct sock *)msk; 2021 const struct mptcp_subflow_context *sf; 2022 u8 sk_err; 2023 2024 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, READ_ONCE(msk->token))) 2025 return -EMSGSIZE; 2026 2027 if (mptcp_event_add_subflow(skb, ssk)) 2028 return -EMSGSIZE; 2029 2030 sf = mptcp_subflow_ctx(ssk); 2031 if (WARN_ON_ONCE(!sf)) 2032 return -EINVAL; 2033 2034 if (nla_put_u8(skb, MPTCP_ATTR_BACKUP, sf->backup)) 2035 return -EMSGSIZE; 2036 2037 if (ssk->sk_bound_dev_if && 2038 nla_put_s32(skb, MPTCP_ATTR_IF_IDX, ssk->sk_bound_dev_if)) 2039 return -EMSGSIZE; 2040 2041 sk_err = READ_ONCE(ssk->sk_err); 2042 if (sk_err && sk->sk_state == TCP_ESTABLISHED && 2043 nla_put_u8(skb, MPTCP_ATTR_ERROR, sk_err)) 2044 return -EMSGSIZE; 2045 2046 return 0; 2047 } 2048 2049 static int mptcp_event_sub_established(struct sk_buff *skb, 2050 const struct mptcp_sock *msk, 2051 const struct sock *ssk) 2052 { 2053 return mptcp_event_put_token_and_ssk(skb, msk, ssk); 2054 } 2055 2056 static int mptcp_event_sub_closed(struct sk_buff *skb, 2057 const struct mptcp_sock *msk, 2058 const struct sock *ssk) 2059 { 2060 const struct mptcp_subflow_context *sf; 2061 2062 if (mptcp_event_put_token_and_ssk(skb, msk, ssk)) 2063 return -EMSGSIZE; 2064 2065 sf = mptcp_subflow_ctx(ssk); 2066 if (!sf->reset_seen) 2067 return 0; 2068 2069 if (nla_put_u32(skb, MPTCP_ATTR_RESET_REASON, sf->reset_reason)) 2070 return -EMSGSIZE; 2071 2072 if (nla_put_u32(skb, MPTCP_ATTR_RESET_FLAGS, sf->reset_transient)) 2073 return -EMSGSIZE; 2074 2075 return 0; 2076 } 2077 2078 static int mptcp_event_created(struct sk_buff *skb, 2079 const struct mptcp_sock *msk, 2080 const struct sock *ssk) 2081 { 2082 int err = nla_put_u32(skb, MPTCP_ATTR_TOKEN, READ_ONCE(msk->token)); 2083 2084 if (err) 2085 return err; 2086 2087 if (nla_put_u8(skb, MPTCP_ATTR_SERVER_SIDE, READ_ONCE(msk->pm.server_side))) 2088 return -EMSGSIZE; 2089 2090 return mptcp_event_add_subflow(skb, ssk); 2091 } 2092 2093 void mptcp_event_addr_removed(const struct mptcp_sock *msk, uint8_t id) 2094 { 2095 struct net *net = sock_net((const struct sock *)msk); 2096 struct nlmsghdr *nlh; 2097 struct sk_buff *skb; 2098 2099 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2100 return; 2101 2102 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); 2103 if (!skb) 2104 return; 2105 2106 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, MPTCP_EVENT_REMOVED); 2107 if (!nlh) 2108 goto nla_put_failure; 2109 2110 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, READ_ONCE(msk->token))) 2111 goto nla_put_failure; 2112 2113 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, id)) 2114 goto nla_put_failure; 2115 2116 genlmsg_end(skb, nlh); 2117 mptcp_nl_mcast_send(net, skb, GFP_ATOMIC); 2118 return; 2119 2120 nla_put_failure: 2121 nlmsg_free(skb); 2122 } 2123 2124 void mptcp_event_addr_announced(const struct sock *ssk, 2125 const struct mptcp_addr_info *info) 2126 { 2127 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 2128 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 2129 struct net *net = sock_net(ssk); 2130 struct nlmsghdr *nlh; 2131 struct sk_buff *skb; 2132 2133 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2134 return; 2135 2136 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); 2137 if (!skb) 2138 return; 2139 2140 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, 2141 MPTCP_EVENT_ANNOUNCED); 2142 if (!nlh) 2143 goto nla_put_failure; 2144 2145 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, READ_ONCE(msk->token))) 2146 goto nla_put_failure; 2147 2148 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, info->id)) 2149 goto nla_put_failure; 2150 2151 if (nla_put_be16(skb, MPTCP_ATTR_DPORT, 2152 info->port == 0 ? 2153 inet_sk(ssk)->inet_dport : 2154 info->port)) 2155 goto nla_put_failure; 2156 2157 switch (info->family) { 2158 case AF_INET: 2159 if (nla_put_in_addr(skb, MPTCP_ATTR_DADDR4, info->addr.s_addr)) 2160 goto nla_put_failure; 2161 break; 2162 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 2163 case AF_INET6: 2164 if (nla_put_in6_addr(skb, MPTCP_ATTR_DADDR6, &info->addr6)) 2165 goto nla_put_failure; 2166 break; 2167 #endif 2168 default: 2169 WARN_ON_ONCE(1); 2170 goto nla_put_failure; 2171 } 2172 2173 genlmsg_end(skb, nlh); 2174 mptcp_nl_mcast_send(net, skb, GFP_ATOMIC); 2175 return; 2176 2177 nla_put_failure: 2178 nlmsg_free(skb); 2179 } 2180 2181 void mptcp_event_pm_listener(const struct sock *ssk, 2182 enum mptcp_event_type event) 2183 { 2184 const struct inet_sock *issk = inet_sk(ssk); 2185 struct net *net = sock_net(ssk); 2186 struct nlmsghdr *nlh; 2187 struct sk_buff *skb; 2188 2189 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2190 return; 2191 2192 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 2193 if (!skb) 2194 return; 2195 2196 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, event); 2197 if (!nlh) 2198 goto nla_put_failure; 2199 2200 if (nla_put_u16(skb, MPTCP_ATTR_FAMILY, ssk->sk_family)) 2201 goto nla_put_failure; 2202 2203 if (nla_put_be16(skb, MPTCP_ATTR_SPORT, issk->inet_sport)) 2204 goto nla_put_failure; 2205 2206 switch (ssk->sk_family) { 2207 case AF_INET: 2208 if (nla_put_in_addr(skb, MPTCP_ATTR_SADDR4, issk->inet_saddr)) 2209 goto nla_put_failure; 2210 break; 2211 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 2212 case AF_INET6: { 2213 const struct ipv6_pinfo *np = inet6_sk(ssk); 2214 2215 if (nla_put_in6_addr(skb, MPTCP_ATTR_SADDR6, &np->saddr)) 2216 goto nla_put_failure; 2217 break; 2218 } 2219 #endif 2220 default: 2221 WARN_ON_ONCE(1); 2222 goto nla_put_failure; 2223 } 2224 2225 genlmsg_end(skb, nlh); 2226 mptcp_nl_mcast_send(net, skb, GFP_KERNEL); 2227 return; 2228 2229 nla_put_failure: 2230 nlmsg_free(skb); 2231 } 2232 2233 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk, 2234 const struct sock *ssk, gfp_t gfp) 2235 { 2236 struct net *net = sock_net((const struct sock *)msk); 2237 struct nlmsghdr *nlh; 2238 struct sk_buff *skb; 2239 2240 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2241 return; 2242 2243 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, gfp); 2244 if (!skb) 2245 return; 2246 2247 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, type); 2248 if (!nlh) 2249 goto nla_put_failure; 2250 2251 switch (type) { 2252 case MPTCP_EVENT_UNSPEC: 2253 WARN_ON_ONCE(1); 2254 break; 2255 case MPTCP_EVENT_CREATED: 2256 case MPTCP_EVENT_ESTABLISHED: 2257 if (mptcp_event_created(skb, msk, ssk) < 0) 2258 goto nla_put_failure; 2259 break; 2260 case MPTCP_EVENT_CLOSED: 2261 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, READ_ONCE(msk->token)) < 0) 2262 goto nla_put_failure; 2263 break; 2264 case MPTCP_EVENT_ANNOUNCED: 2265 case MPTCP_EVENT_REMOVED: 2266 /* call mptcp_event_addr_announced()/removed instead */ 2267 WARN_ON_ONCE(1); 2268 break; 2269 case MPTCP_EVENT_SUB_ESTABLISHED: 2270 case MPTCP_EVENT_SUB_PRIORITY: 2271 if (mptcp_event_sub_established(skb, msk, ssk) < 0) 2272 goto nla_put_failure; 2273 break; 2274 case MPTCP_EVENT_SUB_CLOSED: 2275 if (mptcp_event_sub_closed(skb, msk, ssk) < 0) 2276 goto nla_put_failure; 2277 break; 2278 case MPTCP_EVENT_LISTENER_CREATED: 2279 case MPTCP_EVENT_LISTENER_CLOSED: 2280 break; 2281 } 2282 2283 genlmsg_end(skb, nlh); 2284 mptcp_nl_mcast_send(net, skb, gfp); 2285 return; 2286 2287 nla_put_failure: 2288 nlmsg_free(skb); 2289 } 2290 2291 struct genl_family mptcp_genl_family __ro_after_init = { 2292 .name = MPTCP_PM_NAME, 2293 .version = MPTCP_PM_VER, 2294 .netnsok = true, 2295 .module = THIS_MODULE, 2296 .ops = mptcp_pm_nl_ops, 2297 .n_ops = ARRAY_SIZE(mptcp_pm_nl_ops), 2298 .resv_start_op = MPTCP_PM_CMD_SUBFLOW_DESTROY + 1, 2299 .mcgrps = mptcp_pm_mcgrps, 2300 .n_mcgrps = ARRAY_SIZE(mptcp_pm_mcgrps), 2301 }; 2302 2303 static int __net_init pm_nl_init_net(struct net *net) 2304 { 2305 struct pm_nl_pernet *pernet = pm_nl_get_pernet(net); 2306 2307 INIT_LIST_HEAD_RCU(&pernet->local_addr_list); 2308 2309 /* Cit. 2 subflows ought to be enough for anybody. */ 2310 pernet->subflows_max = 2; 2311 pernet->next_id = 1; 2312 pernet->stale_loss_cnt = 4; 2313 spin_lock_init(&pernet->lock); 2314 2315 /* No need to initialize other pernet fields, the struct is zeroed at 2316 * allocation time. 2317 */ 2318 2319 return 0; 2320 } 2321 2322 static void __net_exit pm_nl_exit_net(struct list_head *net_list) 2323 { 2324 struct net *net; 2325 2326 list_for_each_entry(net, net_list, exit_list) { 2327 struct pm_nl_pernet *pernet = pm_nl_get_pernet(net); 2328 2329 /* net is removed from namespace list, can't race with 2330 * other modifiers, also netns core already waited for a 2331 * RCU grace period. 2332 */ 2333 __flush_addrs(&pernet->local_addr_list); 2334 } 2335 } 2336 2337 static struct pernet_operations mptcp_pm_pernet_ops = { 2338 .init = pm_nl_init_net, 2339 .exit_batch = pm_nl_exit_net, 2340 .id = &pm_nl_pernet_id, 2341 .size = sizeof(struct pm_nl_pernet), 2342 }; 2343 2344 void __init mptcp_pm_nl_init(void) 2345 { 2346 if (register_pernet_subsys(&mptcp_pm_pernet_ops) < 0) 2347 panic("Failed to register MPTCP PM pernet subsystem.\n"); 2348 2349 if (genl_register_family(&mptcp_genl_family)) 2350 panic("Failed to register MPTCP PM netlink family\n"); 2351 } 2352