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 remove_anno_list_by_saddr(msk, &entry->addr); 1519 if (alist.nr < MPTCP_RM_IDS_MAX) 1520 alist.ids[alist.nr++] = entry->addr.id; 1521 } 1522 1523 if (alist.nr) { 1524 spin_lock_bh(&msk->pm.lock); 1525 mptcp_pm_remove_addr(msk, &alist); 1526 spin_unlock_bh(&msk->pm.lock); 1527 } 1528 } 1529 1530 void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk, 1531 struct list_head *rm_list) 1532 { 1533 struct mptcp_rm_list alist = { .nr = 0 }, slist = { .nr = 0 }; 1534 struct mptcp_pm_addr_entry *entry; 1535 1536 list_for_each_entry(entry, rm_list, list) { 1537 if (lookup_subflow_by_saddr(&msk->conn_list, &entry->addr) && 1538 slist.nr < MPTCP_RM_IDS_MAX) 1539 slist.ids[slist.nr++] = entry->addr.id; 1540 1541 if (remove_anno_list_by_saddr(msk, &entry->addr) && 1542 alist.nr < MPTCP_RM_IDS_MAX) 1543 alist.ids[alist.nr++] = entry->addr.id; 1544 } 1545 1546 if (alist.nr) { 1547 spin_lock_bh(&msk->pm.lock); 1548 mptcp_pm_remove_addr(msk, &alist); 1549 spin_unlock_bh(&msk->pm.lock); 1550 } 1551 if (slist.nr) 1552 mptcp_pm_remove_subflow(msk, &slist); 1553 } 1554 1555 static void mptcp_nl_remove_addrs_list(struct net *net, 1556 struct list_head *rm_list) 1557 { 1558 long s_slot = 0, s_num = 0; 1559 struct mptcp_sock *msk; 1560 1561 if (list_empty(rm_list)) 1562 return; 1563 1564 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1565 struct sock *sk = (struct sock *)msk; 1566 1567 if (!mptcp_pm_is_userspace(msk)) { 1568 lock_sock(sk); 1569 mptcp_pm_remove_addrs_and_subflows(msk, rm_list); 1570 release_sock(sk); 1571 } 1572 1573 sock_put(sk); 1574 cond_resched(); 1575 } 1576 } 1577 1578 /* caller must ensure the RCU grace period is already elapsed */ 1579 static void __flush_addrs(struct list_head *list) 1580 { 1581 while (!list_empty(list)) { 1582 struct mptcp_pm_addr_entry *cur; 1583 1584 cur = list_entry(list->next, 1585 struct mptcp_pm_addr_entry, list); 1586 list_del_rcu(&cur->list); 1587 __mptcp_pm_release_addr_entry(cur); 1588 } 1589 } 1590 1591 static void __reset_counters(struct pm_nl_pernet *pernet) 1592 { 1593 WRITE_ONCE(pernet->add_addr_signal_max, 0); 1594 WRITE_ONCE(pernet->add_addr_accept_max, 0); 1595 WRITE_ONCE(pernet->local_addr_max, 0); 1596 pernet->addrs = 0; 1597 } 1598 1599 int mptcp_pm_nl_flush_addrs_doit(struct sk_buff *skb, struct genl_info *info) 1600 { 1601 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1602 LIST_HEAD(free_list); 1603 1604 spin_lock_bh(&pernet->lock); 1605 list_splice_init(&pernet->local_addr_list, &free_list); 1606 __reset_counters(pernet); 1607 pernet->next_id = 1; 1608 bitmap_zero(pernet->id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); 1609 spin_unlock_bh(&pernet->lock); 1610 mptcp_nl_remove_addrs_list(sock_net(skb->sk), &free_list); 1611 synchronize_rcu(); 1612 __flush_addrs(&free_list); 1613 return 0; 1614 } 1615 1616 static int mptcp_nl_fill_addr(struct sk_buff *skb, 1617 struct mptcp_pm_addr_entry *entry) 1618 { 1619 struct mptcp_addr_info *addr = &entry->addr; 1620 struct nlattr *attr; 1621 1622 attr = nla_nest_start(skb, MPTCP_PM_ATTR_ADDR); 1623 if (!attr) 1624 return -EMSGSIZE; 1625 1626 if (nla_put_u16(skb, MPTCP_PM_ADDR_ATTR_FAMILY, addr->family)) 1627 goto nla_put_failure; 1628 if (nla_put_u16(skb, MPTCP_PM_ADDR_ATTR_PORT, ntohs(addr->port))) 1629 goto nla_put_failure; 1630 if (nla_put_u8(skb, MPTCP_PM_ADDR_ATTR_ID, addr->id)) 1631 goto nla_put_failure; 1632 if (nla_put_u32(skb, MPTCP_PM_ADDR_ATTR_FLAGS, entry->flags)) 1633 goto nla_put_failure; 1634 if (entry->ifindex && 1635 nla_put_s32(skb, MPTCP_PM_ADDR_ATTR_IF_IDX, entry->ifindex)) 1636 goto nla_put_failure; 1637 1638 if (addr->family == AF_INET && 1639 nla_put_in_addr(skb, MPTCP_PM_ADDR_ATTR_ADDR4, 1640 addr->addr.s_addr)) 1641 goto nla_put_failure; 1642 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1643 else if (addr->family == AF_INET6 && 1644 nla_put_in6_addr(skb, MPTCP_PM_ADDR_ATTR_ADDR6, &addr->addr6)) 1645 goto nla_put_failure; 1646 #endif 1647 nla_nest_end(skb, attr); 1648 return 0; 1649 1650 nla_put_failure: 1651 nla_nest_cancel(skb, attr); 1652 return -EMSGSIZE; 1653 } 1654 1655 int mptcp_pm_nl_get_addr_doit(struct sk_buff *skb, struct genl_info *info) 1656 { 1657 struct nlattr *attr = info->attrs[MPTCP_PM_ENDPOINT_ADDR]; 1658 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1659 struct mptcp_pm_addr_entry addr, *entry; 1660 struct sk_buff *msg; 1661 void *reply; 1662 int ret; 1663 1664 ret = mptcp_pm_parse_entry(attr, info, false, &addr); 1665 if (ret < 0) 1666 return ret; 1667 1668 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 1669 if (!msg) 1670 return -ENOMEM; 1671 1672 reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0, 1673 info->genlhdr->cmd); 1674 if (!reply) { 1675 GENL_SET_ERR_MSG(info, "not enough space in Netlink message"); 1676 ret = -EMSGSIZE; 1677 goto fail; 1678 } 1679 1680 spin_lock_bh(&pernet->lock); 1681 entry = __lookup_addr_by_id(pernet, addr.addr.id); 1682 if (!entry) { 1683 GENL_SET_ERR_MSG(info, "address not found"); 1684 ret = -EINVAL; 1685 goto unlock_fail; 1686 } 1687 1688 ret = mptcp_nl_fill_addr(msg, entry); 1689 if (ret) 1690 goto unlock_fail; 1691 1692 genlmsg_end(msg, reply); 1693 ret = genlmsg_reply(msg, info); 1694 spin_unlock_bh(&pernet->lock); 1695 return ret; 1696 1697 unlock_fail: 1698 spin_unlock_bh(&pernet->lock); 1699 1700 fail: 1701 nlmsg_free(msg); 1702 return ret; 1703 } 1704 1705 int mptcp_pm_nl_get_addr_dumpit(struct sk_buff *msg, 1706 struct netlink_callback *cb) 1707 { 1708 struct net *net = sock_net(msg->sk); 1709 struct mptcp_pm_addr_entry *entry; 1710 struct pm_nl_pernet *pernet; 1711 int id = cb->args[0]; 1712 void *hdr; 1713 int i; 1714 1715 pernet = pm_nl_get_pernet(net); 1716 1717 spin_lock_bh(&pernet->lock); 1718 for (i = id; i < MPTCP_PM_MAX_ADDR_ID + 1; i++) { 1719 if (test_bit(i, pernet->id_bitmap)) { 1720 entry = __lookup_addr_by_id(pernet, i); 1721 if (!entry) 1722 break; 1723 1724 if (entry->addr.id <= id) 1725 continue; 1726 1727 hdr = genlmsg_put(msg, NETLINK_CB(cb->skb).portid, 1728 cb->nlh->nlmsg_seq, &mptcp_genl_family, 1729 NLM_F_MULTI, MPTCP_PM_CMD_GET_ADDR); 1730 if (!hdr) 1731 break; 1732 1733 if (mptcp_nl_fill_addr(msg, entry) < 0) { 1734 genlmsg_cancel(msg, hdr); 1735 break; 1736 } 1737 1738 id = entry->addr.id; 1739 genlmsg_end(msg, hdr); 1740 } 1741 } 1742 spin_unlock_bh(&pernet->lock); 1743 1744 cb->args[0] = id; 1745 return msg->len; 1746 } 1747 1748 static int parse_limit(struct genl_info *info, int id, unsigned int *limit) 1749 { 1750 struct nlattr *attr = info->attrs[id]; 1751 1752 if (!attr) 1753 return 0; 1754 1755 *limit = nla_get_u32(attr); 1756 if (*limit > MPTCP_PM_ADDR_MAX) { 1757 GENL_SET_ERR_MSG(info, "limit greater than maximum"); 1758 return -EINVAL; 1759 } 1760 return 0; 1761 } 1762 1763 int mptcp_pm_nl_set_limits_doit(struct sk_buff *skb, struct genl_info *info) 1764 { 1765 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1766 unsigned int rcv_addrs, subflows; 1767 int ret; 1768 1769 spin_lock_bh(&pernet->lock); 1770 rcv_addrs = pernet->add_addr_accept_max; 1771 ret = parse_limit(info, MPTCP_PM_ATTR_RCV_ADD_ADDRS, &rcv_addrs); 1772 if (ret) 1773 goto unlock; 1774 1775 subflows = pernet->subflows_max; 1776 ret = parse_limit(info, MPTCP_PM_ATTR_SUBFLOWS, &subflows); 1777 if (ret) 1778 goto unlock; 1779 1780 WRITE_ONCE(pernet->add_addr_accept_max, rcv_addrs); 1781 WRITE_ONCE(pernet->subflows_max, subflows); 1782 1783 unlock: 1784 spin_unlock_bh(&pernet->lock); 1785 return ret; 1786 } 1787 1788 int mptcp_pm_nl_get_limits_doit(struct sk_buff *skb, struct genl_info *info) 1789 { 1790 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1791 struct sk_buff *msg; 1792 void *reply; 1793 1794 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 1795 if (!msg) 1796 return -ENOMEM; 1797 1798 reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0, 1799 MPTCP_PM_CMD_GET_LIMITS); 1800 if (!reply) 1801 goto fail; 1802 1803 if (nla_put_u32(msg, MPTCP_PM_ATTR_RCV_ADD_ADDRS, 1804 READ_ONCE(pernet->add_addr_accept_max))) 1805 goto fail; 1806 1807 if (nla_put_u32(msg, MPTCP_PM_ATTR_SUBFLOWS, 1808 READ_ONCE(pernet->subflows_max))) 1809 goto fail; 1810 1811 genlmsg_end(msg, reply); 1812 return genlmsg_reply(msg, info); 1813 1814 fail: 1815 GENL_SET_ERR_MSG(info, "not enough space in Netlink message"); 1816 nlmsg_free(msg); 1817 return -EMSGSIZE; 1818 } 1819 1820 static void mptcp_pm_nl_fullmesh(struct mptcp_sock *msk, 1821 struct mptcp_addr_info *addr) 1822 { 1823 struct mptcp_rm_list list = { .nr = 0 }; 1824 1825 list.ids[list.nr++] = addr->id; 1826 1827 spin_lock_bh(&msk->pm.lock); 1828 mptcp_pm_nl_rm_subflow_received(msk, &list); 1829 mptcp_pm_create_subflow_or_signal_addr(msk); 1830 spin_unlock_bh(&msk->pm.lock); 1831 } 1832 1833 static int mptcp_nl_set_flags(struct net *net, 1834 struct mptcp_addr_info *addr, 1835 u8 bkup, u8 changed) 1836 { 1837 long s_slot = 0, s_num = 0; 1838 struct mptcp_sock *msk; 1839 int ret = -EINVAL; 1840 1841 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1842 struct sock *sk = (struct sock *)msk; 1843 1844 if (list_empty(&msk->conn_list) || mptcp_pm_is_userspace(msk)) 1845 goto next; 1846 1847 lock_sock(sk); 1848 if (changed & MPTCP_PM_ADDR_FLAG_BACKUP) 1849 ret = mptcp_pm_nl_mp_prio_send_ack(msk, addr, NULL, bkup); 1850 if (changed & MPTCP_PM_ADDR_FLAG_FULLMESH) 1851 mptcp_pm_nl_fullmesh(msk, addr); 1852 release_sock(sk); 1853 1854 next: 1855 sock_put(sk); 1856 cond_resched(); 1857 } 1858 1859 return ret; 1860 } 1861 1862 int mptcp_pm_nl_set_flags(struct net *net, struct mptcp_pm_addr_entry *addr, u8 bkup) 1863 { 1864 struct pm_nl_pernet *pernet = pm_nl_get_pernet(net); 1865 u8 changed, mask = MPTCP_PM_ADDR_FLAG_BACKUP | 1866 MPTCP_PM_ADDR_FLAG_FULLMESH; 1867 struct mptcp_pm_addr_entry *entry; 1868 u8 lookup_by_id = 0; 1869 1870 if (addr->addr.family == AF_UNSPEC) { 1871 lookup_by_id = 1; 1872 if (!addr->addr.id) 1873 return -EOPNOTSUPP; 1874 } 1875 1876 spin_lock_bh(&pernet->lock); 1877 entry = __lookup_addr(pernet, &addr->addr, lookup_by_id); 1878 if (!entry) { 1879 spin_unlock_bh(&pernet->lock); 1880 return -EINVAL; 1881 } 1882 if ((addr->flags & MPTCP_PM_ADDR_FLAG_FULLMESH) && 1883 (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) { 1884 spin_unlock_bh(&pernet->lock); 1885 return -EINVAL; 1886 } 1887 1888 changed = (addr->flags ^ entry->flags) & mask; 1889 entry->flags = (entry->flags & ~mask) | (addr->flags & mask); 1890 *addr = *entry; 1891 spin_unlock_bh(&pernet->lock); 1892 1893 mptcp_nl_set_flags(net, &addr->addr, bkup, changed); 1894 return 0; 1895 } 1896 1897 int mptcp_pm_nl_set_flags_doit(struct sk_buff *skb, struct genl_info *info) 1898 { 1899 struct mptcp_pm_addr_entry remote = { .addr = { .family = AF_UNSPEC }, }; 1900 struct mptcp_pm_addr_entry addr = { .addr = { .family = AF_UNSPEC }, }; 1901 struct nlattr *attr_rem = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE]; 1902 struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN]; 1903 struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR]; 1904 struct net *net = sock_net(skb->sk); 1905 u8 bkup = 0; 1906 int ret; 1907 1908 ret = mptcp_pm_parse_entry(attr, info, false, &addr); 1909 if (ret < 0) 1910 return ret; 1911 1912 if (attr_rem) { 1913 ret = mptcp_pm_parse_entry(attr_rem, info, false, &remote); 1914 if (ret < 0) 1915 return ret; 1916 } 1917 1918 if (addr.flags & MPTCP_PM_ADDR_FLAG_BACKUP) 1919 bkup = 1; 1920 1921 return mptcp_pm_set_flags(net, token, &addr, &remote, bkup); 1922 } 1923 1924 static void mptcp_nl_mcast_send(struct net *net, struct sk_buff *nlskb, gfp_t gfp) 1925 { 1926 genlmsg_multicast_netns(&mptcp_genl_family, net, 1927 nlskb, 0, MPTCP_PM_EV_GRP_OFFSET, gfp); 1928 } 1929 1930 bool mptcp_userspace_pm_active(const struct mptcp_sock *msk) 1931 { 1932 return genl_has_listeners(&mptcp_genl_family, 1933 sock_net((const struct sock *)msk), 1934 MPTCP_PM_EV_GRP_OFFSET); 1935 } 1936 1937 static int mptcp_event_add_subflow(struct sk_buff *skb, const struct sock *ssk) 1938 { 1939 const struct inet_sock *issk = inet_sk(ssk); 1940 const struct mptcp_subflow_context *sf; 1941 1942 if (nla_put_u16(skb, MPTCP_ATTR_FAMILY, ssk->sk_family)) 1943 return -EMSGSIZE; 1944 1945 switch (ssk->sk_family) { 1946 case AF_INET: 1947 if (nla_put_in_addr(skb, MPTCP_ATTR_SADDR4, issk->inet_saddr)) 1948 return -EMSGSIZE; 1949 if (nla_put_in_addr(skb, MPTCP_ATTR_DADDR4, issk->inet_daddr)) 1950 return -EMSGSIZE; 1951 break; 1952 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1953 case AF_INET6: { 1954 const struct ipv6_pinfo *np = inet6_sk(ssk); 1955 1956 if (nla_put_in6_addr(skb, MPTCP_ATTR_SADDR6, &np->saddr)) 1957 return -EMSGSIZE; 1958 if (nla_put_in6_addr(skb, MPTCP_ATTR_DADDR6, &ssk->sk_v6_daddr)) 1959 return -EMSGSIZE; 1960 break; 1961 } 1962 #endif 1963 default: 1964 WARN_ON_ONCE(1); 1965 return -EMSGSIZE; 1966 } 1967 1968 if (nla_put_be16(skb, MPTCP_ATTR_SPORT, issk->inet_sport)) 1969 return -EMSGSIZE; 1970 if (nla_put_be16(skb, MPTCP_ATTR_DPORT, issk->inet_dport)) 1971 return -EMSGSIZE; 1972 1973 sf = mptcp_subflow_ctx(ssk); 1974 if (WARN_ON_ONCE(!sf)) 1975 return -EINVAL; 1976 1977 if (nla_put_u8(skb, MPTCP_ATTR_LOC_ID, sf->local_id)) 1978 return -EMSGSIZE; 1979 1980 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, sf->remote_id)) 1981 return -EMSGSIZE; 1982 1983 return 0; 1984 } 1985 1986 static int mptcp_event_put_token_and_ssk(struct sk_buff *skb, 1987 const struct mptcp_sock *msk, 1988 const struct sock *ssk) 1989 { 1990 const struct sock *sk = (const struct sock *)msk; 1991 const struct mptcp_subflow_context *sf; 1992 u8 sk_err; 1993 1994 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token)) 1995 return -EMSGSIZE; 1996 1997 if (mptcp_event_add_subflow(skb, ssk)) 1998 return -EMSGSIZE; 1999 2000 sf = mptcp_subflow_ctx(ssk); 2001 if (WARN_ON_ONCE(!sf)) 2002 return -EINVAL; 2003 2004 if (nla_put_u8(skb, MPTCP_ATTR_BACKUP, sf->backup)) 2005 return -EMSGSIZE; 2006 2007 if (ssk->sk_bound_dev_if && 2008 nla_put_s32(skb, MPTCP_ATTR_IF_IDX, ssk->sk_bound_dev_if)) 2009 return -EMSGSIZE; 2010 2011 sk_err = READ_ONCE(ssk->sk_err); 2012 if (sk_err && sk->sk_state == TCP_ESTABLISHED && 2013 nla_put_u8(skb, MPTCP_ATTR_ERROR, sk_err)) 2014 return -EMSGSIZE; 2015 2016 return 0; 2017 } 2018 2019 static int mptcp_event_sub_established(struct sk_buff *skb, 2020 const struct mptcp_sock *msk, 2021 const struct sock *ssk) 2022 { 2023 return mptcp_event_put_token_and_ssk(skb, msk, ssk); 2024 } 2025 2026 static int mptcp_event_sub_closed(struct sk_buff *skb, 2027 const struct mptcp_sock *msk, 2028 const struct sock *ssk) 2029 { 2030 const struct mptcp_subflow_context *sf; 2031 2032 if (mptcp_event_put_token_and_ssk(skb, msk, ssk)) 2033 return -EMSGSIZE; 2034 2035 sf = mptcp_subflow_ctx(ssk); 2036 if (!sf->reset_seen) 2037 return 0; 2038 2039 if (nla_put_u32(skb, MPTCP_ATTR_RESET_REASON, sf->reset_reason)) 2040 return -EMSGSIZE; 2041 2042 if (nla_put_u32(skb, MPTCP_ATTR_RESET_FLAGS, sf->reset_transient)) 2043 return -EMSGSIZE; 2044 2045 return 0; 2046 } 2047 2048 static int mptcp_event_created(struct sk_buff *skb, 2049 const struct mptcp_sock *msk, 2050 const struct sock *ssk) 2051 { 2052 int err = nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token); 2053 2054 if (err) 2055 return err; 2056 2057 if (nla_put_u8(skb, MPTCP_ATTR_SERVER_SIDE, READ_ONCE(msk->pm.server_side))) 2058 return -EMSGSIZE; 2059 2060 return mptcp_event_add_subflow(skb, ssk); 2061 } 2062 2063 void mptcp_event_addr_removed(const struct mptcp_sock *msk, uint8_t id) 2064 { 2065 struct net *net = sock_net((const struct sock *)msk); 2066 struct nlmsghdr *nlh; 2067 struct sk_buff *skb; 2068 2069 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2070 return; 2071 2072 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); 2073 if (!skb) 2074 return; 2075 2076 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, MPTCP_EVENT_REMOVED); 2077 if (!nlh) 2078 goto nla_put_failure; 2079 2080 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token)) 2081 goto nla_put_failure; 2082 2083 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, id)) 2084 goto nla_put_failure; 2085 2086 genlmsg_end(skb, nlh); 2087 mptcp_nl_mcast_send(net, skb, GFP_ATOMIC); 2088 return; 2089 2090 nla_put_failure: 2091 nlmsg_free(skb); 2092 } 2093 2094 void mptcp_event_addr_announced(const struct sock *ssk, 2095 const struct mptcp_addr_info *info) 2096 { 2097 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 2098 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 2099 struct net *net = sock_net(ssk); 2100 struct nlmsghdr *nlh; 2101 struct sk_buff *skb; 2102 2103 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2104 return; 2105 2106 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); 2107 if (!skb) 2108 return; 2109 2110 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, 2111 MPTCP_EVENT_ANNOUNCED); 2112 if (!nlh) 2113 goto nla_put_failure; 2114 2115 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token)) 2116 goto nla_put_failure; 2117 2118 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, info->id)) 2119 goto nla_put_failure; 2120 2121 if (nla_put_be16(skb, MPTCP_ATTR_DPORT, 2122 info->port == 0 ? 2123 inet_sk(ssk)->inet_dport : 2124 info->port)) 2125 goto nla_put_failure; 2126 2127 switch (info->family) { 2128 case AF_INET: 2129 if (nla_put_in_addr(skb, MPTCP_ATTR_DADDR4, info->addr.s_addr)) 2130 goto nla_put_failure; 2131 break; 2132 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 2133 case AF_INET6: 2134 if (nla_put_in6_addr(skb, MPTCP_ATTR_DADDR6, &info->addr6)) 2135 goto nla_put_failure; 2136 break; 2137 #endif 2138 default: 2139 WARN_ON_ONCE(1); 2140 goto nla_put_failure; 2141 } 2142 2143 genlmsg_end(skb, nlh); 2144 mptcp_nl_mcast_send(net, skb, GFP_ATOMIC); 2145 return; 2146 2147 nla_put_failure: 2148 nlmsg_free(skb); 2149 } 2150 2151 void mptcp_event_pm_listener(const struct sock *ssk, 2152 enum mptcp_event_type event) 2153 { 2154 const struct inet_sock *issk = inet_sk(ssk); 2155 struct net *net = sock_net(ssk); 2156 struct nlmsghdr *nlh; 2157 struct sk_buff *skb; 2158 2159 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2160 return; 2161 2162 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 2163 if (!skb) 2164 return; 2165 2166 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, event); 2167 if (!nlh) 2168 goto nla_put_failure; 2169 2170 if (nla_put_u16(skb, MPTCP_ATTR_FAMILY, ssk->sk_family)) 2171 goto nla_put_failure; 2172 2173 if (nla_put_be16(skb, MPTCP_ATTR_SPORT, issk->inet_sport)) 2174 goto nla_put_failure; 2175 2176 switch (ssk->sk_family) { 2177 case AF_INET: 2178 if (nla_put_in_addr(skb, MPTCP_ATTR_SADDR4, issk->inet_saddr)) 2179 goto nla_put_failure; 2180 break; 2181 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 2182 case AF_INET6: { 2183 const struct ipv6_pinfo *np = inet6_sk(ssk); 2184 2185 if (nla_put_in6_addr(skb, MPTCP_ATTR_SADDR6, &np->saddr)) 2186 goto nla_put_failure; 2187 break; 2188 } 2189 #endif 2190 default: 2191 WARN_ON_ONCE(1); 2192 goto nla_put_failure; 2193 } 2194 2195 genlmsg_end(skb, nlh); 2196 mptcp_nl_mcast_send(net, skb, GFP_KERNEL); 2197 return; 2198 2199 nla_put_failure: 2200 nlmsg_free(skb); 2201 } 2202 2203 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk, 2204 const struct sock *ssk, gfp_t gfp) 2205 { 2206 struct net *net = sock_net((const struct sock *)msk); 2207 struct nlmsghdr *nlh; 2208 struct sk_buff *skb; 2209 2210 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2211 return; 2212 2213 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, gfp); 2214 if (!skb) 2215 return; 2216 2217 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, type); 2218 if (!nlh) 2219 goto nla_put_failure; 2220 2221 switch (type) { 2222 case MPTCP_EVENT_UNSPEC: 2223 WARN_ON_ONCE(1); 2224 break; 2225 case MPTCP_EVENT_CREATED: 2226 case MPTCP_EVENT_ESTABLISHED: 2227 if (mptcp_event_created(skb, msk, ssk) < 0) 2228 goto nla_put_failure; 2229 break; 2230 case MPTCP_EVENT_CLOSED: 2231 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token) < 0) 2232 goto nla_put_failure; 2233 break; 2234 case MPTCP_EVENT_ANNOUNCED: 2235 case MPTCP_EVENT_REMOVED: 2236 /* call mptcp_event_addr_announced()/removed instead */ 2237 WARN_ON_ONCE(1); 2238 break; 2239 case MPTCP_EVENT_SUB_ESTABLISHED: 2240 case MPTCP_EVENT_SUB_PRIORITY: 2241 if (mptcp_event_sub_established(skb, msk, ssk) < 0) 2242 goto nla_put_failure; 2243 break; 2244 case MPTCP_EVENT_SUB_CLOSED: 2245 if (mptcp_event_sub_closed(skb, msk, ssk) < 0) 2246 goto nla_put_failure; 2247 break; 2248 case MPTCP_EVENT_LISTENER_CREATED: 2249 case MPTCP_EVENT_LISTENER_CLOSED: 2250 break; 2251 } 2252 2253 genlmsg_end(skb, nlh); 2254 mptcp_nl_mcast_send(net, skb, gfp); 2255 return; 2256 2257 nla_put_failure: 2258 nlmsg_free(skb); 2259 } 2260 2261 static struct genl_family mptcp_genl_family __ro_after_init = { 2262 .name = MPTCP_PM_NAME, 2263 .version = MPTCP_PM_VER, 2264 .netnsok = true, 2265 .module = THIS_MODULE, 2266 .ops = mptcp_pm_nl_ops, 2267 .n_ops = ARRAY_SIZE(mptcp_pm_nl_ops), 2268 .resv_start_op = MPTCP_PM_CMD_SUBFLOW_DESTROY + 1, 2269 .mcgrps = mptcp_pm_mcgrps, 2270 .n_mcgrps = ARRAY_SIZE(mptcp_pm_mcgrps), 2271 }; 2272 2273 static int __net_init pm_nl_init_net(struct net *net) 2274 { 2275 struct pm_nl_pernet *pernet = pm_nl_get_pernet(net); 2276 2277 INIT_LIST_HEAD_RCU(&pernet->local_addr_list); 2278 2279 /* Cit. 2 subflows ought to be enough for anybody. */ 2280 pernet->subflows_max = 2; 2281 pernet->next_id = 1; 2282 pernet->stale_loss_cnt = 4; 2283 spin_lock_init(&pernet->lock); 2284 2285 /* No need to initialize other pernet fields, the struct is zeroed at 2286 * allocation time. 2287 */ 2288 2289 return 0; 2290 } 2291 2292 static void __net_exit pm_nl_exit_net(struct list_head *net_list) 2293 { 2294 struct net *net; 2295 2296 list_for_each_entry(net, net_list, exit_list) { 2297 struct pm_nl_pernet *pernet = pm_nl_get_pernet(net); 2298 2299 /* net is removed from namespace list, can't race with 2300 * other modifiers, also netns core already waited for a 2301 * RCU grace period. 2302 */ 2303 __flush_addrs(&pernet->local_addr_list); 2304 } 2305 } 2306 2307 static struct pernet_operations mptcp_pm_pernet_ops = { 2308 .init = pm_nl_init_net, 2309 .exit_batch = pm_nl_exit_net, 2310 .id = &pm_nl_pernet_id, 2311 .size = sizeof(struct pm_nl_pernet), 2312 }; 2313 2314 void __init mptcp_pm_nl_init(void) 2315 { 2316 if (register_pernet_subsys(&mptcp_pm_pernet_ops) < 0) 2317 panic("Failed to register MPTCP PM pernet subsystem.\n"); 2318 2319 if (genl_register_family(&mptcp_genl_family)) 2320 panic("Failed to register MPTCP PM netlink family\n"); 2321 } 2322