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 inet_sk_state_store(newsk, TCP_LISTEN); 1052 lock_sock(ssk); 1053 err = __inet_listen_sk(ssk, backlog); 1054 if (!err) 1055 mptcp_event_pm_listener(ssk, MPTCP_EVENT_LISTENER_CREATED); 1056 release_sock(ssk); 1057 return err; 1058 } 1059 1060 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc) 1061 { 1062 struct mptcp_pm_addr_entry *entry; 1063 struct pm_nl_pernet *pernet; 1064 int ret = -1; 1065 1066 pernet = pm_nl_get_pernet_from_msk(msk); 1067 1068 rcu_read_lock(); 1069 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 1070 if (mptcp_addresses_equal(&entry->addr, skc, entry->addr.port)) { 1071 ret = entry->addr.id; 1072 break; 1073 } 1074 } 1075 rcu_read_unlock(); 1076 if (ret >= 0) 1077 return ret; 1078 1079 /* address not found, add to local list */ 1080 entry = kmalloc(sizeof(*entry), GFP_ATOMIC); 1081 if (!entry) 1082 return -ENOMEM; 1083 1084 entry->addr = *skc; 1085 entry->addr.id = 0; 1086 entry->addr.port = 0; 1087 entry->ifindex = 0; 1088 entry->flags = MPTCP_PM_ADDR_FLAG_IMPLICIT; 1089 entry->lsk = NULL; 1090 ret = mptcp_pm_nl_append_new_local_addr(pernet, entry); 1091 if (ret < 0) 1092 kfree(entry); 1093 1094 return ret; 1095 } 1096 1097 #define MPTCP_PM_CMD_GRP_OFFSET 0 1098 #define MPTCP_PM_EV_GRP_OFFSET 1 1099 1100 static const struct genl_multicast_group mptcp_pm_mcgrps[] = { 1101 [MPTCP_PM_CMD_GRP_OFFSET] = { .name = MPTCP_PM_CMD_GRP_NAME, }, 1102 [MPTCP_PM_EV_GRP_OFFSET] = { .name = MPTCP_PM_EV_GRP_NAME, 1103 .flags = GENL_UNS_ADMIN_PERM, 1104 }, 1105 }; 1106 1107 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk) 1108 { 1109 struct mptcp_subflow_context *iter, *subflow = mptcp_subflow_ctx(ssk); 1110 struct sock *sk = (struct sock *)msk; 1111 unsigned int active_max_loss_cnt; 1112 struct net *net = sock_net(sk); 1113 unsigned int stale_loss_cnt; 1114 bool slow; 1115 1116 stale_loss_cnt = mptcp_stale_loss_cnt(net); 1117 if (subflow->stale || !stale_loss_cnt || subflow->stale_count <= stale_loss_cnt) 1118 return; 1119 1120 /* look for another available subflow not in loss state */ 1121 active_max_loss_cnt = max_t(int, stale_loss_cnt - 1, 1); 1122 mptcp_for_each_subflow(msk, iter) { 1123 if (iter != subflow && mptcp_subflow_active(iter) && 1124 iter->stale_count < active_max_loss_cnt) { 1125 /* we have some alternatives, try to mark this subflow as idle ...*/ 1126 slow = lock_sock_fast(ssk); 1127 if (!tcp_rtx_and_write_queues_empty(ssk)) { 1128 subflow->stale = 1; 1129 __mptcp_retransmit_pending_data(sk); 1130 MPTCP_INC_STATS(net, MPTCP_MIB_SUBFLOWSTALE); 1131 } 1132 unlock_sock_fast(ssk, slow); 1133 1134 /* always try to push the pending data regardless of re-injections: 1135 * we can possibly use backup subflows now, and subflow selection 1136 * is cheap under the msk socket lock 1137 */ 1138 __mptcp_push_pending(sk, 0); 1139 return; 1140 } 1141 } 1142 } 1143 1144 static int mptcp_pm_family_to_addr(int family) 1145 { 1146 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1147 if (family == AF_INET6) 1148 return MPTCP_PM_ADDR_ATTR_ADDR6; 1149 #endif 1150 return MPTCP_PM_ADDR_ATTR_ADDR4; 1151 } 1152 1153 static int mptcp_pm_parse_pm_addr_attr(struct nlattr *tb[], 1154 const struct nlattr *attr, 1155 struct genl_info *info, 1156 struct mptcp_addr_info *addr, 1157 bool require_family) 1158 { 1159 int err, addr_addr; 1160 1161 if (!attr) { 1162 GENL_SET_ERR_MSG(info, "missing address info"); 1163 return -EINVAL; 1164 } 1165 1166 /* no validation needed - was already done via nested policy */ 1167 err = nla_parse_nested_deprecated(tb, MPTCP_PM_ADDR_ATTR_MAX, attr, 1168 mptcp_pm_address_nl_policy, info->extack); 1169 if (err) 1170 return err; 1171 1172 if (tb[MPTCP_PM_ADDR_ATTR_ID]) 1173 addr->id = nla_get_u8(tb[MPTCP_PM_ADDR_ATTR_ID]); 1174 1175 if (!tb[MPTCP_PM_ADDR_ATTR_FAMILY]) { 1176 if (!require_family) 1177 return 0; 1178 1179 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1180 "missing family"); 1181 return -EINVAL; 1182 } 1183 1184 addr->family = nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_FAMILY]); 1185 if (addr->family != AF_INET 1186 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1187 && addr->family != AF_INET6 1188 #endif 1189 ) { 1190 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1191 "unknown address family"); 1192 return -EINVAL; 1193 } 1194 addr_addr = mptcp_pm_family_to_addr(addr->family); 1195 if (!tb[addr_addr]) { 1196 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1197 "missing address data"); 1198 return -EINVAL; 1199 } 1200 1201 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1202 if (addr->family == AF_INET6) 1203 addr->addr6 = nla_get_in6_addr(tb[addr_addr]); 1204 else 1205 #endif 1206 addr->addr.s_addr = nla_get_in_addr(tb[addr_addr]); 1207 1208 if (tb[MPTCP_PM_ADDR_ATTR_PORT]) 1209 addr->port = htons(nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_PORT])); 1210 1211 return 0; 1212 } 1213 1214 int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info, 1215 struct mptcp_addr_info *addr) 1216 { 1217 struct nlattr *tb[MPTCP_PM_ADDR_ATTR_MAX + 1]; 1218 1219 memset(addr, 0, sizeof(*addr)); 1220 1221 return mptcp_pm_parse_pm_addr_attr(tb, attr, info, addr, true); 1222 } 1223 1224 int mptcp_pm_parse_entry(struct nlattr *attr, struct genl_info *info, 1225 bool require_family, 1226 struct mptcp_pm_addr_entry *entry) 1227 { 1228 struct nlattr *tb[MPTCP_PM_ADDR_ATTR_MAX + 1]; 1229 int err; 1230 1231 memset(entry, 0, sizeof(*entry)); 1232 1233 err = mptcp_pm_parse_pm_addr_attr(tb, attr, info, &entry->addr, require_family); 1234 if (err) 1235 return err; 1236 1237 if (tb[MPTCP_PM_ADDR_ATTR_IF_IDX]) { 1238 u32 val = nla_get_s32(tb[MPTCP_PM_ADDR_ATTR_IF_IDX]); 1239 1240 entry->ifindex = val; 1241 } 1242 1243 if (tb[MPTCP_PM_ADDR_ATTR_FLAGS]) 1244 entry->flags = nla_get_u32(tb[MPTCP_PM_ADDR_ATTR_FLAGS]); 1245 1246 if (tb[MPTCP_PM_ADDR_ATTR_PORT]) 1247 entry->addr.port = htons(nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_PORT])); 1248 1249 return 0; 1250 } 1251 1252 static struct pm_nl_pernet *genl_info_pm_nl(struct genl_info *info) 1253 { 1254 return pm_nl_get_pernet(genl_info_net(info)); 1255 } 1256 1257 static int mptcp_nl_add_subflow_or_signal_addr(struct net *net) 1258 { 1259 struct mptcp_sock *msk; 1260 long s_slot = 0, s_num = 0; 1261 1262 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1263 struct sock *sk = (struct sock *)msk; 1264 1265 if (!READ_ONCE(msk->fully_established) || 1266 mptcp_pm_is_userspace(msk)) 1267 goto next; 1268 1269 lock_sock(sk); 1270 spin_lock_bh(&msk->pm.lock); 1271 mptcp_pm_create_subflow_or_signal_addr(msk); 1272 spin_unlock_bh(&msk->pm.lock); 1273 release_sock(sk); 1274 1275 next: 1276 sock_put(sk); 1277 cond_resched(); 1278 } 1279 1280 return 0; 1281 } 1282 1283 int mptcp_pm_nl_add_addr_doit(struct sk_buff *skb, struct genl_info *info) 1284 { 1285 struct nlattr *attr = info->attrs[MPTCP_PM_ENDPOINT_ADDR]; 1286 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1287 struct mptcp_pm_addr_entry addr, *entry; 1288 int ret; 1289 1290 ret = mptcp_pm_parse_entry(attr, info, true, &addr); 1291 if (ret < 0) 1292 return ret; 1293 1294 if (addr.addr.port && !(addr.flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) { 1295 GENL_SET_ERR_MSG(info, "flags must have signal when using port"); 1296 return -EINVAL; 1297 } 1298 1299 if (addr.flags & MPTCP_PM_ADDR_FLAG_SIGNAL && 1300 addr.flags & MPTCP_PM_ADDR_FLAG_FULLMESH) { 1301 GENL_SET_ERR_MSG(info, "flags mustn't have both signal and fullmesh"); 1302 return -EINVAL; 1303 } 1304 1305 if (addr.flags & MPTCP_PM_ADDR_FLAG_IMPLICIT) { 1306 GENL_SET_ERR_MSG(info, "can't create IMPLICIT endpoint"); 1307 return -EINVAL; 1308 } 1309 1310 entry = kzalloc(sizeof(*entry), GFP_KERNEL_ACCOUNT); 1311 if (!entry) { 1312 GENL_SET_ERR_MSG(info, "can't allocate addr"); 1313 return -ENOMEM; 1314 } 1315 1316 *entry = addr; 1317 if (entry->addr.port) { 1318 ret = mptcp_pm_nl_create_listen_socket(skb->sk, entry); 1319 if (ret) { 1320 GENL_SET_ERR_MSG_FMT(info, "create listen socket error: %d", ret); 1321 goto out_free; 1322 } 1323 } 1324 ret = mptcp_pm_nl_append_new_local_addr(pernet, entry); 1325 if (ret < 0) { 1326 GENL_SET_ERR_MSG_FMT(info, "too many addresses or duplicate one: %d", ret); 1327 goto out_free; 1328 } 1329 1330 mptcp_nl_add_subflow_or_signal_addr(sock_net(skb->sk)); 1331 return 0; 1332 1333 out_free: 1334 __mptcp_pm_release_addr_entry(entry); 1335 return ret; 1336 } 1337 1338 int mptcp_pm_nl_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, unsigned int id, 1339 u8 *flags, int *ifindex) 1340 { 1341 struct mptcp_pm_addr_entry *entry; 1342 struct sock *sk = (struct sock *)msk; 1343 struct net *net = sock_net(sk); 1344 1345 rcu_read_lock(); 1346 entry = __lookup_addr_by_id(pm_nl_get_pernet(net), id); 1347 if (entry) { 1348 *flags = entry->flags; 1349 *ifindex = entry->ifindex; 1350 } 1351 rcu_read_unlock(); 1352 1353 return 0; 1354 } 1355 1356 static bool remove_anno_list_by_saddr(struct mptcp_sock *msk, 1357 const struct mptcp_addr_info *addr) 1358 { 1359 struct mptcp_pm_add_entry *entry; 1360 1361 entry = mptcp_pm_del_add_timer(msk, addr, false); 1362 if (entry) { 1363 list_del(&entry->list); 1364 kfree(entry); 1365 return true; 1366 } 1367 1368 return false; 1369 } 1370 1371 static bool mptcp_pm_remove_anno_addr(struct mptcp_sock *msk, 1372 const struct mptcp_addr_info *addr, 1373 bool force) 1374 { 1375 struct mptcp_rm_list list = { .nr = 0 }; 1376 bool ret; 1377 1378 list.ids[list.nr++] = addr->id; 1379 1380 ret = remove_anno_list_by_saddr(msk, addr); 1381 if (ret || force) { 1382 spin_lock_bh(&msk->pm.lock); 1383 mptcp_pm_remove_addr(msk, &list); 1384 spin_unlock_bh(&msk->pm.lock); 1385 } 1386 return ret; 1387 } 1388 1389 static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net, 1390 const struct mptcp_pm_addr_entry *entry) 1391 { 1392 const struct mptcp_addr_info *addr = &entry->addr; 1393 struct mptcp_rm_list list = { .nr = 0 }; 1394 long s_slot = 0, s_num = 0; 1395 struct mptcp_sock *msk; 1396 1397 pr_debug("remove_id=%d", addr->id); 1398 1399 list.ids[list.nr++] = addr->id; 1400 1401 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1402 struct sock *sk = (struct sock *)msk; 1403 bool remove_subflow; 1404 1405 if (mptcp_pm_is_userspace(msk)) 1406 goto next; 1407 1408 if (list_empty(&msk->conn_list)) { 1409 mptcp_pm_remove_anno_addr(msk, addr, false); 1410 goto next; 1411 } 1412 1413 lock_sock(sk); 1414 remove_subflow = lookup_subflow_by_saddr(&msk->conn_list, addr); 1415 mptcp_pm_remove_anno_addr(msk, addr, remove_subflow && 1416 !(entry->flags & MPTCP_PM_ADDR_FLAG_IMPLICIT)); 1417 if (remove_subflow) 1418 mptcp_pm_remove_subflow(msk, &list); 1419 release_sock(sk); 1420 1421 next: 1422 sock_put(sk); 1423 cond_resched(); 1424 } 1425 1426 return 0; 1427 } 1428 1429 static int mptcp_nl_remove_id_zero_address(struct net *net, 1430 struct mptcp_addr_info *addr) 1431 { 1432 struct mptcp_rm_list list = { .nr = 0 }; 1433 long s_slot = 0, s_num = 0; 1434 struct mptcp_sock *msk; 1435 1436 list.ids[list.nr++] = 0; 1437 1438 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1439 struct sock *sk = (struct sock *)msk; 1440 struct mptcp_addr_info msk_local; 1441 1442 if (list_empty(&msk->conn_list) || mptcp_pm_is_userspace(msk)) 1443 goto next; 1444 1445 mptcp_local_address((struct sock_common *)msk, &msk_local); 1446 if (!mptcp_addresses_equal(&msk_local, addr, addr->port)) 1447 goto next; 1448 1449 lock_sock(sk); 1450 spin_lock_bh(&msk->pm.lock); 1451 mptcp_pm_remove_addr(msk, &list); 1452 mptcp_pm_nl_rm_subflow_received(msk, &list); 1453 spin_unlock_bh(&msk->pm.lock); 1454 release_sock(sk); 1455 1456 next: 1457 sock_put(sk); 1458 cond_resched(); 1459 } 1460 1461 return 0; 1462 } 1463 1464 int mptcp_pm_nl_del_addr_doit(struct sk_buff *skb, struct genl_info *info) 1465 { 1466 struct nlattr *attr = info->attrs[MPTCP_PM_ENDPOINT_ADDR]; 1467 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1468 struct mptcp_pm_addr_entry addr, *entry; 1469 unsigned int addr_max; 1470 int ret; 1471 1472 ret = mptcp_pm_parse_entry(attr, info, false, &addr); 1473 if (ret < 0) 1474 return ret; 1475 1476 /* the zero id address is special: the first address used by the msk 1477 * always gets such an id, so different subflows can have different zero 1478 * id addresses. Additionally zero id is not accounted for in id_bitmap. 1479 * Let's use an 'mptcp_rm_list' instead of the common remove code. 1480 */ 1481 if (addr.addr.id == 0) 1482 return mptcp_nl_remove_id_zero_address(sock_net(skb->sk), &addr.addr); 1483 1484 spin_lock_bh(&pernet->lock); 1485 entry = __lookup_addr_by_id(pernet, addr.addr.id); 1486 if (!entry) { 1487 GENL_SET_ERR_MSG(info, "address not found"); 1488 spin_unlock_bh(&pernet->lock); 1489 return -EINVAL; 1490 } 1491 if (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL) { 1492 addr_max = pernet->add_addr_signal_max; 1493 WRITE_ONCE(pernet->add_addr_signal_max, addr_max - 1); 1494 } 1495 if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) { 1496 addr_max = pernet->local_addr_max; 1497 WRITE_ONCE(pernet->local_addr_max, addr_max - 1); 1498 } 1499 1500 pernet->addrs--; 1501 list_del_rcu(&entry->list); 1502 __clear_bit(entry->addr.id, pernet->id_bitmap); 1503 spin_unlock_bh(&pernet->lock); 1504 1505 mptcp_nl_remove_subflow_and_signal_addr(sock_net(skb->sk), entry); 1506 synchronize_rcu(); 1507 __mptcp_pm_release_addr_entry(entry); 1508 1509 return ret; 1510 } 1511 1512 void mptcp_pm_remove_addrs(struct mptcp_sock *msk, struct list_head *rm_list) 1513 { 1514 struct mptcp_rm_list alist = { .nr = 0 }; 1515 struct mptcp_pm_addr_entry *entry; 1516 1517 list_for_each_entry(entry, rm_list, list) { 1518 if ((remove_anno_list_by_saddr(msk, &entry->addr) || 1519 lookup_subflow_by_saddr(&msk->conn_list, &entry->addr)) && 1520 alist.nr < MPTCP_RM_IDS_MAX) 1521 alist.ids[alist.nr++] = entry->addr.id; 1522 } 1523 1524 if (alist.nr) { 1525 spin_lock_bh(&msk->pm.lock); 1526 mptcp_pm_remove_addr(msk, &alist); 1527 spin_unlock_bh(&msk->pm.lock); 1528 } 1529 } 1530 1531 void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk, 1532 struct list_head *rm_list) 1533 { 1534 struct mptcp_rm_list alist = { .nr = 0 }, slist = { .nr = 0 }; 1535 struct mptcp_pm_addr_entry *entry; 1536 1537 list_for_each_entry(entry, rm_list, list) { 1538 if (lookup_subflow_by_saddr(&msk->conn_list, &entry->addr) && 1539 slist.nr < MPTCP_RM_IDS_MAX) 1540 slist.ids[slist.nr++] = entry->addr.id; 1541 1542 if (remove_anno_list_by_saddr(msk, &entry->addr) && 1543 alist.nr < MPTCP_RM_IDS_MAX) 1544 alist.ids[alist.nr++] = entry->addr.id; 1545 } 1546 1547 if (alist.nr) { 1548 spin_lock_bh(&msk->pm.lock); 1549 mptcp_pm_remove_addr(msk, &alist); 1550 spin_unlock_bh(&msk->pm.lock); 1551 } 1552 if (slist.nr) 1553 mptcp_pm_remove_subflow(msk, &slist); 1554 } 1555 1556 static void mptcp_nl_remove_addrs_list(struct net *net, 1557 struct list_head *rm_list) 1558 { 1559 long s_slot = 0, s_num = 0; 1560 struct mptcp_sock *msk; 1561 1562 if (list_empty(rm_list)) 1563 return; 1564 1565 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1566 struct sock *sk = (struct sock *)msk; 1567 1568 if (!mptcp_pm_is_userspace(msk)) { 1569 lock_sock(sk); 1570 mptcp_pm_remove_addrs_and_subflows(msk, rm_list); 1571 release_sock(sk); 1572 } 1573 1574 sock_put(sk); 1575 cond_resched(); 1576 } 1577 } 1578 1579 /* caller must ensure the RCU grace period is already elapsed */ 1580 static void __flush_addrs(struct list_head *list) 1581 { 1582 while (!list_empty(list)) { 1583 struct mptcp_pm_addr_entry *cur; 1584 1585 cur = list_entry(list->next, 1586 struct mptcp_pm_addr_entry, list); 1587 list_del_rcu(&cur->list); 1588 __mptcp_pm_release_addr_entry(cur); 1589 } 1590 } 1591 1592 static void __reset_counters(struct pm_nl_pernet *pernet) 1593 { 1594 WRITE_ONCE(pernet->add_addr_signal_max, 0); 1595 WRITE_ONCE(pernet->add_addr_accept_max, 0); 1596 WRITE_ONCE(pernet->local_addr_max, 0); 1597 pernet->addrs = 0; 1598 } 1599 1600 int mptcp_pm_nl_flush_addrs_doit(struct sk_buff *skb, struct genl_info *info) 1601 { 1602 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1603 LIST_HEAD(free_list); 1604 1605 spin_lock_bh(&pernet->lock); 1606 list_splice_init(&pernet->local_addr_list, &free_list); 1607 __reset_counters(pernet); 1608 pernet->next_id = 1; 1609 bitmap_zero(pernet->id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); 1610 spin_unlock_bh(&pernet->lock); 1611 mptcp_nl_remove_addrs_list(sock_net(skb->sk), &free_list); 1612 synchronize_rcu(); 1613 __flush_addrs(&free_list); 1614 return 0; 1615 } 1616 1617 static int mptcp_nl_fill_addr(struct sk_buff *skb, 1618 struct mptcp_pm_addr_entry *entry) 1619 { 1620 struct mptcp_addr_info *addr = &entry->addr; 1621 struct nlattr *attr; 1622 1623 attr = nla_nest_start(skb, MPTCP_PM_ATTR_ADDR); 1624 if (!attr) 1625 return -EMSGSIZE; 1626 1627 if (nla_put_u16(skb, MPTCP_PM_ADDR_ATTR_FAMILY, addr->family)) 1628 goto nla_put_failure; 1629 if (nla_put_u16(skb, MPTCP_PM_ADDR_ATTR_PORT, ntohs(addr->port))) 1630 goto nla_put_failure; 1631 if (nla_put_u8(skb, MPTCP_PM_ADDR_ATTR_ID, addr->id)) 1632 goto nla_put_failure; 1633 if (nla_put_u32(skb, MPTCP_PM_ADDR_ATTR_FLAGS, entry->flags)) 1634 goto nla_put_failure; 1635 if (entry->ifindex && 1636 nla_put_s32(skb, MPTCP_PM_ADDR_ATTR_IF_IDX, entry->ifindex)) 1637 goto nla_put_failure; 1638 1639 if (addr->family == AF_INET && 1640 nla_put_in_addr(skb, MPTCP_PM_ADDR_ATTR_ADDR4, 1641 addr->addr.s_addr)) 1642 goto nla_put_failure; 1643 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1644 else if (addr->family == AF_INET6 && 1645 nla_put_in6_addr(skb, MPTCP_PM_ADDR_ATTR_ADDR6, &addr->addr6)) 1646 goto nla_put_failure; 1647 #endif 1648 nla_nest_end(skb, attr); 1649 return 0; 1650 1651 nla_put_failure: 1652 nla_nest_cancel(skb, attr); 1653 return -EMSGSIZE; 1654 } 1655 1656 int mptcp_pm_nl_get_addr_doit(struct sk_buff *skb, struct genl_info *info) 1657 { 1658 struct nlattr *attr = info->attrs[MPTCP_PM_ENDPOINT_ADDR]; 1659 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1660 struct mptcp_pm_addr_entry addr, *entry; 1661 struct sk_buff *msg; 1662 void *reply; 1663 int ret; 1664 1665 ret = mptcp_pm_parse_entry(attr, info, false, &addr); 1666 if (ret < 0) 1667 return ret; 1668 1669 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 1670 if (!msg) 1671 return -ENOMEM; 1672 1673 reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0, 1674 info->genlhdr->cmd); 1675 if (!reply) { 1676 GENL_SET_ERR_MSG(info, "not enough space in Netlink message"); 1677 ret = -EMSGSIZE; 1678 goto fail; 1679 } 1680 1681 spin_lock_bh(&pernet->lock); 1682 entry = __lookup_addr_by_id(pernet, addr.addr.id); 1683 if (!entry) { 1684 GENL_SET_ERR_MSG(info, "address not found"); 1685 ret = -EINVAL; 1686 goto unlock_fail; 1687 } 1688 1689 ret = mptcp_nl_fill_addr(msg, entry); 1690 if (ret) 1691 goto unlock_fail; 1692 1693 genlmsg_end(msg, reply); 1694 ret = genlmsg_reply(msg, info); 1695 spin_unlock_bh(&pernet->lock); 1696 return ret; 1697 1698 unlock_fail: 1699 spin_unlock_bh(&pernet->lock); 1700 1701 fail: 1702 nlmsg_free(msg); 1703 return ret; 1704 } 1705 1706 int mptcp_pm_nl_get_addr_dumpit(struct sk_buff *msg, 1707 struct netlink_callback *cb) 1708 { 1709 struct net *net = sock_net(msg->sk); 1710 struct mptcp_pm_addr_entry *entry; 1711 struct pm_nl_pernet *pernet; 1712 int id = cb->args[0]; 1713 void *hdr; 1714 int i; 1715 1716 pernet = pm_nl_get_pernet(net); 1717 1718 spin_lock_bh(&pernet->lock); 1719 for (i = id; i < MPTCP_PM_MAX_ADDR_ID + 1; i++) { 1720 if (test_bit(i, pernet->id_bitmap)) { 1721 entry = __lookup_addr_by_id(pernet, i); 1722 if (!entry) 1723 break; 1724 1725 if (entry->addr.id <= id) 1726 continue; 1727 1728 hdr = genlmsg_put(msg, NETLINK_CB(cb->skb).portid, 1729 cb->nlh->nlmsg_seq, &mptcp_genl_family, 1730 NLM_F_MULTI, MPTCP_PM_CMD_GET_ADDR); 1731 if (!hdr) 1732 break; 1733 1734 if (mptcp_nl_fill_addr(msg, entry) < 0) { 1735 genlmsg_cancel(msg, hdr); 1736 break; 1737 } 1738 1739 id = entry->addr.id; 1740 genlmsg_end(msg, hdr); 1741 } 1742 } 1743 spin_unlock_bh(&pernet->lock); 1744 1745 cb->args[0] = id; 1746 return msg->len; 1747 } 1748 1749 static int parse_limit(struct genl_info *info, int id, unsigned int *limit) 1750 { 1751 struct nlattr *attr = info->attrs[id]; 1752 1753 if (!attr) 1754 return 0; 1755 1756 *limit = nla_get_u32(attr); 1757 if (*limit > MPTCP_PM_ADDR_MAX) { 1758 GENL_SET_ERR_MSG(info, "limit greater than maximum"); 1759 return -EINVAL; 1760 } 1761 return 0; 1762 } 1763 1764 int mptcp_pm_nl_set_limits_doit(struct sk_buff *skb, struct genl_info *info) 1765 { 1766 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1767 unsigned int rcv_addrs, subflows; 1768 int ret; 1769 1770 spin_lock_bh(&pernet->lock); 1771 rcv_addrs = pernet->add_addr_accept_max; 1772 ret = parse_limit(info, MPTCP_PM_ATTR_RCV_ADD_ADDRS, &rcv_addrs); 1773 if (ret) 1774 goto unlock; 1775 1776 subflows = pernet->subflows_max; 1777 ret = parse_limit(info, MPTCP_PM_ATTR_SUBFLOWS, &subflows); 1778 if (ret) 1779 goto unlock; 1780 1781 WRITE_ONCE(pernet->add_addr_accept_max, rcv_addrs); 1782 WRITE_ONCE(pernet->subflows_max, subflows); 1783 1784 unlock: 1785 spin_unlock_bh(&pernet->lock); 1786 return ret; 1787 } 1788 1789 int mptcp_pm_nl_get_limits_doit(struct sk_buff *skb, struct genl_info *info) 1790 { 1791 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1792 struct sk_buff *msg; 1793 void *reply; 1794 1795 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 1796 if (!msg) 1797 return -ENOMEM; 1798 1799 reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0, 1800 MPTCP_PM_CMD_GET_LIMITS); 1801 if (!reply) 1802 goto fail; 1803 1804 if (nla_put_u32(msg, MPTCP_PM_ATTR_RCV_ADD_ADDRS, 1805 READ_ONCE(pernet->add_addr_accept_max))) 1806 goto fail; 1807 1808 if (nla_put_u32(msg, MPTCP_PM_ATTR_SUBFLOWS, 1809 READ_ONCE(pernet->subflows_max))) 1810 goto fail; 1811 1812 genlmsg_end(msg, reply); 1813 return genlmsg_reply(msg, info); 1814 1815 fail: 1816 GENL_SET_ERR_MSG(info, "not enough space in Netlink message"); 1817 nlmsg_free(msg); 1818 return -EMSGSIZE; 1819 } 1820 1821 static void mptcp_pm_nl_fullmesh(struct mptcp_sock *msk, 1822 struct mptcp_addr_info *addr) 1823 { 1824 struct mptcp_rm_list list = { .nr = 0 }; 1825 1826 list.ids[list.nr++] = addr->id; 1827 1828 spin_lock_bh(&msk->pm.lock); 1829 mptcp_pm_nl_rm_subflow_received(msk, &list); 1830 mptcp_pm_create_subflow_or_signal_addr(msk); 1831 spin_unlock_bh(&msk->pm.lock); 1832 } 1833 1834 static int mptcp_nl_set_flags(struct net *net, 1835 struct mptcp_addr_info *addr, 1836 u8 bkup, u8 changed) 1837 { 1838 long s_slot = 0, s_num = 0; 1839 struct mptcp_sock *msk; 1840 int ret = -EINVAL; 1841 1842 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1843 struct sock *sk = (struct sock *)msk; 1844 1845 if (list_empty(&msk->conn_list) || mptcp_pm_is_userspace(msk)) 1846 goto next; 1847 1848 lock_sock(sk); 1849 if (changed & MPTCP_PM_ADDR_FLAG_BACKUP) 1850 ret = mptcp_pm_nl_mp_prio_send_ack(msk, addr, NULL, bkup); 1851 if (changed & MPTCP_PM_ADDR_FLAG_FULLMESH) 1852 mptcp_pm_nl_fullmesh(msk, addr); 1853 release_sock(sk); 1854 1855 next: 1856 sock_put(sk); 1857 cond_resched(); 1858 } 1859 1860 return ret; 1861 } 1862 1863 int mptcp_pm_nl_set_flags(struct net *net, struct mptcp_pm_addr_entry *addr, u8 bkup) 1864 { 1865 struct pm_nl_pernet *pernet = pm_nl_get_pernet(net); 1866 u8 changed, mask = MPTCP_PM_ADDR_FLAG_BACKUP | 1867 MPTCP_PM_ADDR_FLAG_FULLMESH; 1868 struct mptcp_pm_addr_entry *entry; 1869 u8 lookup_by_id = 0; 1870 1871 if (addr->addr.family == AF_UNSPEC) { 1872 lookup_by_id = 1; 1873 if (!addr->addr.id) 1874 return -EOPNOTSUPP; 1875 } 1876 1877 spin_lock_bh(&pernet->lock); 1878 entry = __lookup_addr(pernet, &addr->addr, lookup_by_id); 1879 if (!entry) { 1880 spin_unlock_bh(&pernet->lock); 1881 return -EINVAL; 1882 } 1883 if ((addr->flags & MPTCP_PM_ADDR_FLAG_FULLMESH) && 1884 (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) { 1885 spin_unlock_bh(&pernet->lock); 1886 return -EINVAL; 1887 } 1888 1889 changed = (addr->flags ^ entry->flags) & mask; 1890 entry->flags = (entry->flags & ~mask) | (addr->flags & mask); 1891 *addr = *entry; 1892 spin_unlock_bh(&pernet->lock); 1893 1894 mptcp_nl_set_flags(net, &addr->addr, bkup, changed); 1895 return 0; 1896 } 1897 1898 int mptcp_pm_nl_set_flags_doit(struct sk_buff *skb, struct genl_info *info) 1899 { 1900 struct mptcp_pm_addr_entry remote = { .addr = { .family = AF_UNSPEC }, }; 1901 struct mptcp_pm_addr_entry addr = { .addr = { .family = AF_UNSPEC }, }; 1902 struct nlattr *attr_rem = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE]; 1903 struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN]; 1904 struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR]; 1905 struct net *net = sock_net(skb->sk); 1906 u8 bkup = 0; 1907 int ret; 1908 1909 ret = mptcp_pm_parse_entry(attr, info, false, &addr); 1910 if (ret < 0) 1911 return ret; 1912 1913 if (attr_rem) { 1914 ret = mptcp_pm_parse_entry(attr_rem, info, false, &remote); 1915 if (ret < 0) 1916 return ret; 1917 } 1918 1919 if (addr.flags & MPTCP_PM_ADDR_FLAG_BACKUP) 1920 bkup = 1; 1921 1922 return mptcp_pm_set_flags(net, token, &addr, &remote, bkup); 1923 } 1924 1925 static void mptcp_nl_mcast_send(struct net *net, struct sk_buff *nlskb, gfp_t gfp) 1926 { 1927 genlmsg_multicast_netns(&mptcp_genl_family, net, 1928 nlskb, 0, MPTCP_PM_EV_GRP_OFFSET, gfp); 1929 } 1930 1931 bool mptcp_userspace_pm_active(const struct mptcp_sock *msk) 1932 { 1933 return genl_has_listeners(&mptcp_genl_family, 1934 sock_net((const struct sock *)msk), 1935 MPTCP_PM_EV_GRP_OFFSET); 1936 } 1937 1938 static int mptcp_event_add_subflow(struct sk_buff *skb, const struct sock *ssk) 1939 { 1940 const struct inet_sock *issk = inet_sk(ssk); 1941 const struct mptcp_subflow_context *sf; 1942 1943 if (nla_put_u16(skb, MPTCP_ATTR_FAMILY, ssk->sk_family)) 1944 return -EMSGSIZE; 1945 1946 switch (ssk->sk_family) { 1947 case AF_INET: 1948 if (nla_put_in_addr(skb, MPTCP_ATTR_SADDR4, issk->inet_saddr)) 1949 return -EMSGSIZE; 1950 if (nla_put_in_addr(skb, MPTCP_ATTR_DADDR4, issk->inet_daddr)) 1951 return -EMSGSIZE; 1952 break; 1953 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1954 case AF_INET6: { 1955 const struct ipv6_pinfo *np = inet6_sk(ssk); 1956 1957 if (nla_put_in6_addr(skb, MPTCP_ATTR_SADDR6, &np->saddr)) 1958 return -EMSGSIZE; 1959 if (nla_put_in6_addr(skb, MPTCP_ATTR_DADDR6, &ssk->sk_v6_daddr)) 1960 return -EMSGSIZE; 1961 break; 1962 } 1963 #endif 1964 default: 1965 WARN_ON_ONCE(1); 1966 return -EMSGSIZE; 1967 } 1968 1969 if (nla_put_be16(skb, MPTCP_ATTR_SPORT, issk->inet_sport)) 1970 return -EMSGSIZE; 1971 if (nla_put_be16(skb, MPTCP_ATTR_DPORT, issk->inet_dport)) 1972 return -EMSGSIZE; 1973 1974 sf = mptcp_subflow_ctx(ssk); 1975 if (WARN_ON_ONCE(!sf)) 1976 return -EINVAL; 1977 1978 if (nla_put_u8(skb, MPTCP_ATTR_LOC_ID, sf->local_id)) 1979 return -EMSGSIZE; 1980 1981 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, sf->remote_id)) 1982 return -EMSGSIZE; 1983 1984 return 0; 1985 } 1986 1987 static int mptcp_event_put_token_and_ssk(struct sk_buff *skb, 1988 const struct mptcp_sock *msk, 1989 const struct sock *ssk) 1990 { 1991 const struct sock *sk = (const struct sock *)msk; 1992 const struct mptcp_subflow_context *sf; 1993 u8 sk_err; 1994 1995 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token)) 1996 return -EMSGSIZE; 1997 1998 if (mptcp_event_add_subflow(skb, ssk)) 1999 return -EMSGSIZE; 2000 2001 sf = mptcp_subflow_ctx(ssk); 2002 if (WARN_ON_ONCE(!sf)) 2003 return -EINVAL; 2004 2005 if (nla_put_u8(skb, MPTCP_ATTR_BACKUP, sf->backup)) 2006 return -EMSGSIZE; 2007 2008 if (ssk->sk_bound_dev_if && 2009 nla_put_s32(skb, MPTCP_ATTR_IF_IDX, ssk->sk_bound_dev_if)) 2010 return -EMSGSIZE; 2011 2012 sk_err = READ_ONCE(ssk->sk_err); 2013 if (sk_err && sk->sk_state == TCP_ESTABLISHED && 2014 nla_put_u8(skb, MPTCP_ATTR_ERROR, sk_err)) 2015 return -EMSGSIZE; 2016 2017 return 0; 2018 } 2019 2020 static int mptcp_event_sub_established(struct sk_buff *skb, 2021 const struct mptcp_sock *msk, 2022 const struct sock *ssk) 2023 { 2024 return mptcp_event_put_token_and_ssk(skb, msk, ssk); 2025 } 2026 2027 static int mptcp_event_sub_closed(struct sk_buff *skb, 2028 const struct mptcp_sock *msk, 2029 const struct sock *ssk) 2030 { 2031 const struct mptcp_subflow_context *sf; 2032 2033 if (mptcp_event_put_token_and_ssk(skb, msk, ssk)) 2034 return -EMSGSIZE; 2035 2036 sf = mptcp_subflow_ctx(ssk); 2037 if (!sf->reset_seen) 2038 return 0; 2039 2040 if (nla_put_u32(skb, MPTCP_ATTR_RESET_REASON, sf->reset_reason)) 2041 return -EMSGSIZE; 2042 2043 if (nla_put_u32(skb, MPTCP_ATTR_RESET_FLAGS, sf->reset_transient)) 2044 return -EMSGSIZE; 2045 2046 return 0; 2047 } 2048 2049 static int mptcp_event_created(struct sk_buff *skb, 2050 const struct mptcp_sock *msk, 2051 const struct sock *ssk) 2052 { 2053 int err = nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token); 2054 2055 if (err) 2056 return err; 2057 2058 if (nla_put_u8(skb, MPTCP_ATTR_SERVER_SIDE, READ_ONCE(msk->pm.server_side))) 2059 return -EMSGSIZE; 2060 2061 return mptcp_event_add_subflow(skb, ssk); 2062 } 2063 2064 void mptcp_event_addr_removed(const struct mptcp_sock *msk, uint8_t id) 2065 { 2066 struct net *net = sock_net((const struct sock *)msk); 2067 struct nlmsghdr *nlh; 2068 struct sk_buff *skb; 2069 2070 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2071 return; 2072 2073 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); 2074 if (!skb) 2075 return; 2076 2077 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, MPTCP_EVENT_REMOVED); 2078 if (!nlh) 2079 goto nla_put_failure; 2080 2081 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token)) 2082 goto nla_put_failure; 2083 2084 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, id)) 2085 goto nla_put_failure; 2086 2087 genlmsg_end(skb, nlh); 2088 mptcp_nl_mcast_send(net, skb, GFP_ATOMIC); 2089 return; 2090 2091 nla_put_failure: 2092 nlmsg_free(skb); 2093 } 2094 2095 void mptcp_event_addr_announced(const struct sock *ssk, 2096 const struct mptcp_addr_info *info) 2097 { 2098 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 2099 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 2100 struct net *net = sock_net(ssk); 2101 struct nlmsghdr *nlh; 2102 struct sk_buff *skb; 2103 2104 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2105 return; 2106 2107 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); 2108 if (!skb) 2109 return; 2110 2111 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, 2112 MPTCP_EVENT_ANNOUNCED); 2113 if (!nlh) 2114 goto nla_put_failure; 2115 2116 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token)) 2117 goto nla_put_failure; 2118 2119 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, info->id)) 2120 goto nla_put_failure; 2121 2122 if (nla_put_be16(skb, MPTCP_ATTR_DPORT, 2123 info->port == 0 ? 2124 inet_sk(ssk)->inet_dport : 2125 info->port)) 2126 goto nla_put_failure; 2127 2128 switch (info->family) { 2129 case AF_INET: 2130 if (nla_put_in_addr(skb, MPTCP_ATTR_DADDR4, info->addr.s_addr)) 2131 goto nla_put_failure; 2132 break; 2133 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 2134 case AF_INET6: 2135 if (nla_put_in6_addr(skb, MPTCP_ATTR_DADDR6, &info->addr6)) 2136 goto nla_put_failure; 2137 break; 2138 #endif 2139 default: 2140 WARN_ON_ONCE(1); 2141 goto nla_put_failure; 2142 } 2143 2144 genlmsg_end(skb, nlh); 2145 mptcp_nl_mcast_send(net, skb, GFP_ATOMIC); 2146 return; 2147 2148 nla_put_failure: 2149 nlmsg_free(skb); 2150 } 2151 2152 void mptcp_event_pm_listener(const struct sock *ssk, 2153 enum mptcp_event_type event) 2154 { 2155 const struct inet_sock *issk = inet_sk(ssk); 2156 struct net *net = sock_net(ssk); 2157 struct nlmsghdr *nlh; 2158 struct sk_buff *skb; 2159 2160 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2161 return; 2162 2163 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 2164 if (!skb) 2165 return; 2166 2167 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, event); 2168 if (!nlh) 2169 goto nla_put_failure; 2170 2171 if (nla_put_u16(skb, MPTCP_ATTR_FAMILY, ssk->sk_family)) 2172 goto nla_put_failure; 2173 2174 if (nla_put_be16(skb, MPTCP_ATTR_SPORT, issk->inet_sport)) 2175 goto nla_put_failure; 2176 2177 switch (ssk->sk_family) { 2178 case AF_INET: 2179 if (nla_put_in_addr(skb, MPTCP_ATTR_SADDR4, issk->inet_saddr)) 2180 goto nla_put_failure; 2181 break; 2182 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 2183 case AF_INET6: { 2184 const struct ipv6_pinfo *np = inet6_sk(ssk); 2185 2186 if (nla_put_in6_addr(skb, MPTCP_ATTR_SADDR6, &np->saddr)) 2187 goto nla_put_failure; 2188 break; 2189 } 2190 #endif 2191 default: 2192 WARN_ON_ONCE(1); 2193 goto nla_put_failure; 2194 } 2195 2196 genlmsg_end(skb, nlh); 2197 mptcp_nl_mcast_send(net, skb, GFP_KERNEL); 2198 return; 2199 2200 nla_put_failure: 2201 nlmsg_free(skb); 2202 } 2203 2204 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk, 2205 const struct sock *ssk, gfp_t gfp) 2206 { 2207 struct net *net = sock_net((const struct sock *)msk); 2208 struct nlmsghdr *nlh; 2209 struct sk_buff *skb; 2210 2211 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2212 return; 2213 2214 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, gfp); 2215 if (!skb) 2216 return; 2217 2218 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, type); 2219 if (!nlh) 2220 goto nla_put_failure; 2221 2222 switch (type) { 2223 case MPTCP_EVENT_UNSPEC: 2224 WARN_ON_ONCE(1); 2225 break; 2226 case MPTCP_EVENT_CREATED: 2227 case MPTCP_EVENT_ESTABLISHED: 2228 if (mptcp_event_created(skb, msk, ssk) < 0) 2229 goto nla_put_failure; 2230 break; 2231 case MPTCP_EVENT_CLOSED: 2232 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token) < 0) 2233 goto nla_put_failure; 2234 break; 2235 case MPTCP_EVENT_ANNOUNCED: 2236 case MPTCP_EVENT_REMOVED: 2237 /* call mptcp_event_addr_announced()/removed instead */ 2238 WARN_ON_ONCE(1); 2239 break; 2240 case MPTCP_EVENT_SUB_ESTABLISHED: 2241 case MPTCP_EVENT_SUB_PRIORITY: 2242 if (mptcp_event_sub_established(skb, msk, ssk) < 0) 2243 goto nla_put_failure; 2244 break; 2245 case MPTCP_EVENT_SUB_CLOSED: 2246 if (mptcp_event_sub_closed(skb, msk, ssk) < 0) 2247 goto nla_put_failure; 2248 break; 2249 case MPTCP_EVENT_LISTENER_CREATED: 2250 case MPTCP_EVENT_LISTENER_CLOSED: 2251 break; 2252 } 2253 2254 genlmsg_end(skb, nlh); 2255 mptcp_nl_mcast_send(net, skb, gfp); 2256 return; 2257 2258 nla_put_failure: 2259 nlmsg_free(skb); 2260 } 2261 2262 static struct genl_family mptcp_genl_family __ro_after_init = { 2263 .name = MPTCP_PM_NAME, 2264 .version = MPTCP_PM_VER, 2265 .netnsok = true, 2266 .module = THIS_MODULE, 2267 .ops = mptcp_pm_nl_ops, 2268 .n_ops = ARRAY_SIZE(mptcp_pm_nl_ops), 2269 .resv_start_op = MPTCP_PM_CMD_SUBFLOW_DESTROY + 1, 2270 .mcgrps = mptcp_pm_mcgrps, 2271 .n_mcgrps = ARRAY_SIZE(mptcp_pm_mcgrps), 2272 }; 2273 2274 static int __net_init pm_nl_init_net(struct net *net) 2275 { 2276 struct pm_nl_pernet *pernet = pm_nl_get_pernet(net); 2277 2278 INIT_LIST_HEAD_RCU(&pernet->local_addr_list); 2279 2280 /* Cit. 2 subflows ought to be enough for anybody. */ 2281 pernet->subflows_max = 2; 2282 pernet->next_id = 1; 2283 pernet->stale_loss_cnt = 4; 2284 spin_lock_init(&pernet->lock); 2285 2286 /* No need to initialize other pernet fields, the struct is zeroed at 2287 * allocation time. 2288 */ 2289 2290 return 0; 2291 } 2292 2293 static void __net_exit pm_nl_exit_net(struct list_head *net_list) 2294 { 2295 struct net *net; 2296 2297 list_for_each_entry(net, net_list, exit_list) { 2298 struct pm_nl_pernet *pernet = pm_nl_get_pernet(net); 2299 2300 /* net is removed from namespace list, can't race with 2301 * other modifiers, also netns core already waited for a 2302 * RCU grace period. 2303 */ 2304 __flush_addrs(&pernet->local_addr_list); 2305 } 2306 } 2307 2308 static struct pernet_operations mptcp_pm_pernet_ops = { 2309 .init = pm_nl_init_net, 2310 .exit_batch = pm_nl_exit_net, 2311 .id = &pm_nl_pernet_id, 2312 .size = sizeof(struct pm_nl_pernet), 2313 }; 2314 2315 void __init mptcp_pm_nl_init(void) 2316 { 2317 if (register_pernet_subsys(&mptcp_pm_pernet_ops) < 0) 2318 panic("Failed to register MPTCP PM pernet subsystem.\n"); 2319 2320 if (genl_register_family(&mptcp_genl_family)) 2321 panic("Failed to register MPTCP PM netlink family\n"); 2322 } 2323