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 /* Fill all the remote addresses into the array addrs[], 400 * and return the array size. 401 */ 402 static unsigned int fill_remote_addresses_vec(struct mptcp_sock *msk, 403 struct mptcp_addr_info *local, 404 bool fullmesh, 405 struct mptcp_addr_info *addrs) 406 { 407 bool deny_id0 = READ_ONCE(msk->pm.remote_deny_join_id0); 408 struct sock *sk = (struct sock *)msk, *ssk; 409 struct mptcp_subflow_context *subflow; 410 struct mptcp_addr_info remote = { 0 }; 411 unsigned int subflows_max; 412 int i = 0; 413 414 subflows_max = mptcp_pm_get_subflows_max(msk); 415 remote_address((struct sock_common *)sk, &remote); 416 417 /* Non-fullmesh endpoint, fill in the single entry 418 * corresponding to the primary MPC subflow remote address 419 */ 420 if (!fullmesh) { 421 if (deny_id0) 422 return 0; 423 424 if (!mptcp_pm_addr_families_match(sk, local, &remote)) 425 return 0; 426 427 msk->pm.subflows++; 428 addrs[i++] = remote; 429 } else { 430 DECLARE_BITMAP(unavail_id, MPTCP_PM_MAX_ADDR_ID + 1); 431 432 /* Forbid creation of new subflows matching existing 433 * ones, possibly already created by incoming ADD_ADDR 434 */ 435 bitmap_zero(unavail_id, MPTCP_PM_MAX_ADDR_ID + 1); 436 mptcp_for_each_subflow(msk, subflow) 437 if (READ_ONCE(subflow->local_id) == local->id) 438 __set_bit(subflow->remote_id, unavail_id); 439 440 mptcp_for_each_subflow(msk, subflow) { 441 ssk = mptcp_subflow_tcp_sock(subflow); 442 remote_address((struct sock_common *)ssk, &addrs[i]); 443 addrs[i].id = READ_ONCE(subflow->remote_id); 444 if (deny_id0 && !addrs[i].id) 445 continue; 446 447 if (test_bit(addrs[i].id, unavail_id)) 448 continue; 449 450 if (!mptcp_pm_addr_families_match(sk, local, &addrs[i])) 451 continue; 452 453 if (msk->pm.subflows < subflows_max) { 454 /* forbid creating multiple address towards 455 * this id 456 */ 457 __set_bit(addrs[i].id, unavail_id); 458 msk->pm.subflows++; 459 i++; 460 } 461 } 462 } 463 464 return i; 465 } 466 467 static void __mptcp_pm_send_ack(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow, 468 bool prio, bool backup) 469 { 470 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 471 bool slow; 472 473 pr_debug("send ack for %s", 474 prio ? "mp_prio" : (mptcp_pm_should_add_signal(msk) ? "add_addr" : "rm_addr")); 475 476 slow = lock_sock_fast(ssk); 477 if (prio) { 478 subflow->send_mp_prio = 1; 479 subflow->backup = backup; 480 subflow->request_bkup = backup; 481 } 482 483 __mptcp_subflow_send_ack(ssk); 484 unlock_sock_fast(ssk, slow); 485 } 486 487 static void mptcp_pm_send_ack(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow, 488 bool prio, bool backup) 489 { 490 spin_unlock_bh(&msk->pm.lock); 491 __mptcp_pm_send_ack(msk, subflow, prio, backup); 492 spin_lock_bh(&msk->pm.lock); 493 } 494 495 static struct mptcp_pm_addr_entry * 496 __lookup_addr_by_id(struct pm_nl_pernet *pernet, unsigned int id) 497 { 498 struct mptcp_pm_addr_entry *entry; 499 500 list_for_each_entry(entry, &pernet->local_addr_list, list) { 501 if (entry->addr.id == id) 502 return entry; 503 } 504 return NULL; 505 } 506 507 static struct mptcp_pm_addr_entry * 508 __lookup_addr(struct pm_nl_pernet *pernet, const struct mptcp_addr_info *info, 509 bool lookup_by_id) 510 { 511 struct mptcp_pm_addr_entry *entry; 512 513 list_for_each_entry(entry, &pernet->local_addr_list, list) { 514 if ((!lookup_by_id && 515 mptcp_addresses_equal(&entry->addr, info, entry->addr.port)) || 516 (lookup_by_id && entry->addr.id == info->id)) 517 return entry; 518 } 519 return NULL; 520 } 521 522 static void mptcp_pm_create_subflow_or_signal_addr(struct mptcp_sock *msk) 523 { 524 struct sock *sk = (struct sock *)msk; 525 struct mptcp_pm_addr_entry *local; 526 unsigned int add_addr_signal_max; 527 unsigned int local_addr_max; 528 struct pm_nl_pernet *pernet; 529 unsigned int subflows_max; 530 531 pernet = pm_nl_get_pernet(sock_net(sk)); 532 533 add_addr_signal_max = mptcp_pm_get_add_addr_signal_max(msk); 534 local_addr_max = mptcp_pm_get_local_addr_max(msk); 535 subflows_max = mptcp_pm_get_subflows_max(msk); 536 537 /* do lazy endpoint usage accounting for the MPC subflows */ 538 if (unlikely(!(msk->pm.status & BIT(MPTCP_PM_MPC_ENDPOINT_ACCOUNTED))) && msk->first) { 539 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(msk->first); 540 struct mptcp_pm_addr_entry *entry; 541 struct mptcp_addr_info mpc_addr; 542 bool backup = false; 543 544 mptcp_local_address((struct sock_common *)msk->first, &mpc_addr); 545 rcu_read_lock(); 546 entry = __lookup_addr(pernet, &mpc_addr, false); 547 if (entry) { 548 __clear_bit(entry->addr.id, msk->pm.id_avail_bitmap); 549 msk->mpc_endpoint_id = entry->addr.id; 550 backup = !!(entry->flags & MPTCP_PM_ADDR_FLAG_BACKUP); 551 } 552 rcu_read_unlock(); 553 554 if (backup) 555 mptcp_pm_send_ack(msk, subflow, true, backup); 556 557 msk->pm.status |= BIT(MPTCP_PM_MPC_ENDPOINT_ACCOUNTED); 558 } 559 560 pr_debug("local %d:%d signal %d:%d subflows %d:%d\n", 561 msk->pm.local_addr_used, local_addr_max, 562 msk->pm.add_addr_signaled, add_addr_signal_max, 563 msk->pm.subflows, subflows_max); 564 565 /* check first for announce */ 566 if (msk->pm.add_addr_signaled < add_addr_signal_max) { 567 local = select_signal_address(pernet, msk); 568 569 /* due to racing events on both ends we can reach here while 570 * previous add address is still running: if we invoke now 571 * mptcp_pm_announce_addr(), that will fail and the 572 * corresponding id will be marked as used. 573 * Instead let the PM machinery reschedule us when the 574 * current address announce will be completed. 575 */ 576 if (msk->pm.addr_signal & BIT(MPTCP_ADD_ADDR_SIGNAL)) 577 return; 578 579 if (local) { 580 if (mptcp_pm_alloc_anno_list(msk, &local->addr)) { 581 __clear_bit(local->addr.id, msk->pm.id_avail_bitmap); 582 msk->pm.add_addr_signaled++; 583 mptcp_pm_announce_addr(msk, &local->addr, false); 584 mptcp_pm_nl_addr_send_ack(msk); 585 } 586 } 587 } 588 589 /* check if should create a new subflow */ 590 while (msk->pm.local_addr_used < local_addr_max && 591 msk->pm.subflows < subflows_max) { 592 struct mptcp_addr_info addrs[MPTCP_PM_ADDR_MAX]; 593 bool fullmesh; 594 int i, nr; 595 596 local = select_local_address(pernet, msk); 597 if (!local) 598 break; 599 600 fullmesh = !!(local->flags & MPTCP_PM_ADDR_FLAG_FULLMESH); 601 602 msk->pm.local_addr_used++; 603 __clear_bit(local->addr.id, msk->pm.id_avail_bitmap); 604 nr = fill_remote_addresses_vec(msk, &local->addr, fullmesh, addrs); 605 if (nr == 0) 606 continue; 607 608 spin_unlock_bh(&msk->pm.lock); 609 for (i = 0; i < nr; i++) 610 __mptcp_subflow_connect(sk, &local->addr, &addrs[i]); 611 spin_lock_bh(&msk->pm.lock); 612 } 613 mptcp_pm_nl_check_work_pending(msk); 614 } 615 616 static void mptcp_pm_nl_fully_established(struct mptcp_sock *msk) 617 { 618 mptcp_pm_create_subflow_or_signal_addr(msk); 619 } 620 621 static void mptcp_pm_nl_subflow_established(struct mptcp_sock *msk) 622 { 623 mptcp_pm_create_subflow_or_signal_addr(msk); 624 } 625 626 /* Fill all the local addresses into the array addrs[], 627 * and return the array size. 628 */ 629 static unsigned int fill_local_addresses_vec(struct mptcp_sock *msk, 630 struct mptcp_addr_info *remote, 631 struct mptcp_addr_info *addrs) 632 { 633 struct sock *sk = (struct sock *)msk; 634 struct mptcp_pm_addr_entry *entry; 635 struct pm_nl_pernet *pernet; 636 unsigned int subflows_max; 637 int i = 0; 638 639 pernet = pm_nl_get_pernet_from_msk(msk); 640 subflows_max = mptcp_pm_get_subflows_max(msk); 641 642 rcu_read_lock(); 643 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 644 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_FULLMESH)) 645 continue; 646 647 if (!mptcp_pm_addr_families_match(sk, &entry->addr, remote)) 648 continue; 649 650 if (msk->pm.subflows < subflows_max) { 651 msk->pm.subflows++; 652 addrs[i++] = entry->addr; 653 } 654 } 655 rcu_read_unlock(); 656 657 /* If the array is empty, fill in the single 658 * 'IPADDRANY' local address 659 */ 660 if (!i) { 661 struct mptcp_addr_info local; 662 663 memset(&local, 0, sizeof(local)); 664 local.family = 665 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 666 remote->family == AF_INET6 && 667 ipv6_addr_v4mapped(&remote->addr6) ? AF_INET : 668 #endif 669 remote->family; 670 671 if (!mptcp_pm_addr_families_match(sk, &local, remote)) 672 return 0; 673 674 msk->pm.subflows++; 675 addrs[i++] = local; 676 } 677 678 return i; 679 } 680 681 static void mptcp_pm_nl_add_addr_received(struct mptcp_sock *msk) 682 { 683 struct mptcp_addr_info addrs[MPTCP_PM_ADDR_MAX]; 684 struct sock *sk = (struct sock *)msk; 685 unsigned int add_addr_accept_max; 686 struct mptcp_addr_info remote; 687 unsigned int subflows_max; 688 int i, nr; 689 690 add_addr_accept_max = mptcp_pm_get_add_addr_accept_max(msk); 691 subflows_max = mptcp_pm_get_subflows_max(msk); 692 693 pr_debug("accepted %d:%d remote family %d", 694 msk->pm.add_addr_accepted, add_addr_accept_max, 695 msk->pm.remote.family); 696 697 remote = msk->pm.remote; 698 mptcp_pm_announce_addr(msk, &remote, true); 699 mptcp_pm_nl_addr_send_ack(msk); 700 701 if (lookup_subflow_by_daddr(&msk->conn_list, &remote)) 702 return; 703 704 /* pick id 0 port, if none is provided the remote address */ 705 if (!remote.port) 706 remote.port = sk->sk_dport; 707 708 /* connect to the specified remote address, using whatever 709 * local address the routing configuration will pick. 710 */ 711 nr = fill_local_addresses_vec(msk, &remote, addrs); 712 if (nr == 0) 713 return; 714 715 msk->pm.add_addr_accepted++; 716 if (msk->pm.add_addr_accepted >= add_addr_accept_max || 717 msk->pm.subflows >= subflows_max) 718 WRITE_ONCE(msk->pm.accept_addr, false); 719 720 spin_unlock_bh(&msk->pm.lock); 721 for (i = 0; i < nr; i++) 722 __mptcp_subflow_connect(sk, &addrs[i], &remote); 723 spin_lock_bh(&msk->pm.lock); 724 } 725 726 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk) 727 { 728 struct mptcp_subflow_context *subflow; 729 730 msk_owned_by_me(msk); 731 lockdep_assert_held(&msk->pm.lock); 732 733 if (!mptcp_pm_should_add_signal(msk) && 734 !mptcp_pm_should_rm_signal(msk)) 735 return; 736 737 subflow = list_first_entry_or_null(&msk->conn_list, typeof(*subflow), node); 738 if (subflow) 739 mptcp_pm_send_ack(msk, subflow, false, false); 740 } 741 742 int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk, 743 struct mptcp_addr_info *addr, 744 struct mptcp_addr_info *rem, 745 u8 bkup) 746 { 747 struct mptcp_subflow_context *subflow; 748 749 pr_debug("bkup=%d", bkup); 750 751 mptcp_for_each_subflow(msk, subflow) { 752 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 753 struct mptcp_addr_info local, remote; 754 755 mptcp_local_address((struct sock_common *)ssk, &local); 756 if (!mptcp_addresses_equal(&local, addr, addr->port)) 757 continue; 758 759 if (rem && rem->family != AF_UNSPEC) { 760 remote_address((struct sock_common *)ssk, &remote); 761 if (!mptcp_addresses_equal(&remote, rem, rem->port)) 762 continue; 763 } 764 765 __mptcp_pm_send_ack(msk, subflow, true, bkup); 766 return 0; 767 } 768 769 return -EINVAL; 770 } 771 772 static bool mptcp_local_id_match(const struct mptcp_sock *msk, u8 local_id, u8 id) 773 { 774 return local_id == id || (!local_id && msk->mpc_endpoint_id == id); 775 } 776 777 static void mptcp_pm_nl_rm_addr_or_subflow(struct mptcp_sock *msk, 778 const struct mptcp_rm_list *rm_list, 779 enum linux_mptcp_mib_field rm_type) 780 { 781 struct mptcp_subflow_context *subflow, *tmp; 782 struct sock *sk = (struct sock *)msk; 783 u8 i; 784 785 pr_debug("%s rm_list_nr %d", 786 rm_type == MPTCP_MIB_RMADDR ? "address" : "subflow", rm_list->nr); 787 788 msk_owned_by_me(msk); 789 790 if (sk->sk_state == TCP_LISTEN) 791 return; 792 793 if (!rm_list->nr) 794 return; 795 796 if (list_empty(&msk->conn_list)) 797 return; 798 799 for (i = 0; i < rm_list->nr; i++) { 800 u8 rm_id = rm_list->ids[i]; 801 bool removed = false; 802 803 mptcp_for_each_subflow_safe(msk, subflow, tmp) { 804 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 805 u8 remote_id = READ_ONCE(subflow->remote_id); 806 int how = RCV_SHUTDOWN | SEND_SHUTDOWN; 807 u8 id = subflow_get_local_id(subflow); 808 809 if (rm_type == MPTCP_MIB_RMADDR && remote_id != rm_id) 810 continue; 811 if (rm_type == MPTCP_MIB_RMSUBFLOW && !mptcp_local_id_match(msk, id, rm_id)) 812 continue; 813 814 pr_debug(" -> %s rm_list_ids[%d]=%u local_id=%u remote_id=%u mpc_id=%u", 815 rm_type == MPTCP_MIB_RMADDR ? "address" : "subflow", 816 i, rm_id, id, remote_id, msk->mpc_endpoint_id); 817 spin_unlock_bh(&msk->pm.lock); 818 mptcp_subflow_shutdown(sk, ssk, how); 819 820 /* the following takes care of updating the subflows counter */ 821 mptcp_close_ssk(sk, ssk, subflow); 822 spin_lock_bh(&msk->pm.lock); 823 824 removed = true; 825 __MPTCP_INC_STATS(sock_net(sk), rm_type); 826 } 827 if (rm_type == MPTCP_MIB_RMSUBFLOW) 828 __set_bit(rm_id ? rm_id : msk->mpc_endpoint_id, msk->pm.id_avail_bitmap); 829 if (!removed) 830 continue; 831 832 if (!mptcp_pm_is_kernel(msk)) 833 continue; 834 835 if (rm_type == MPTCP_MIB_RMADDR) { 836 msk->pm.add_addr_accepted--; 837 WRITE_ONCE(msk->pm.accept_addr, true); 838 } else if (rm_type == MPTCP_MIB_RMSUBFLOW) { 839 msk->pm.local_addr_used--; 840 } 841 } 842 } 843 844 static void mptcp_pm_nl_rm_addr_received(struct mptcp_sock *msk) 845 { 846 mptcp_pm_nl_rm_addr_or_subflow(msk, &msk->pm.rm_list_rx, MPTCP_MIB_RMADDR); 847 } 848 849 void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk, 850 const struct mptcp_rm_list *rm_list) 851 { 852 mptcp_pm_nl_rm_addr_or_subflow(msk, rm_list, MPTCP_MIB_RMSUBFLOW); 853 } 854 855 void mptcp_pm_nl_work(struct mptcp_sock *msk) 856 { 857 struct mptcp_pm_data *pm = &msk->pm; 858 859 msk_owned_by_me(msk); 860 861 if (!(pm->status & MPTCP_PM_WORK_MASK)) 862 return; 863 864 spin_lock_bh(&msk->pm.lock); 865 866 pr_debug("msk=%p status=%x", msk, pm->status); 867 if (pm->status & BIT(MPTCP_PM_ADD_ADDR_RECEIVED)) { 868 pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_RECEIVED); 869 mptcp_pm_nl_add_addr_received(msk); 870 } 871 if (pm->status & BIT(MPTCP_PM_ADD_ADDR_SEND_ACK)) { 872 pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_SEND_ACK); 873 mptcp_pm_nl_addr_send_ack(msk); 874 } 875 if (pm->status & BIT(MPTCP_PM_RM_ADDR_RECEIVED)) { 876 pm->status &= ~BIT(MPTCP_PM_RM_ADDR_RECEIVED); 877 mptcp_pm_nl_rm_addr_received(msk); 878 } 879 if (pm->status & BIT(MPTCP_PM_ESTABLISHED)) { 880 pm->status &= ~BIT(MPTCP_PM_ESTABLISHED); 881 mptcp_pm_nl_fully_established(msk); 882 } 883 if (pm->status & BIT(MPTCP_PM_SUBFLOW_ESTABLISHED)) { 884 pm->status &= ~BIT(MPTCP_PM_SUBFLOW_ESTABLISHED); 885 mptcp_pm_nl_subflow_established(msk); 886 } 887 888 spin_unlock_bh(&msk->pm.lock); 889 } 890 891 static bool address_use_port(struct mptcp_pm_addr_entry *entry) 892 { 893 return (entry->flags & 894 (MPTCP_PM_ADDR_FLAG_SIGNAL | MPTCP_PM_ADDR_FLAG_SUBFLOW)) == 895 MPTCP_PM_ADDR_FLAG_SIGNAL; 896 } 897 898 /* caller must ensure the RCU grace period is already elapsed */ 899 static void __mptcp_pm_release_addr_entry(struct mptcp_pm_addr_entry *entry) 900 { 901 if (entry->lsk) 902 sock_release(entry->lsk); 903 kfree(entry); 904 } 905 906 static int mptcp_pm_nl_append_new_local_addr(struct pm_nl_pernet *pernet, 907 struct mptcp_pm_addr_entry *entry, 908 bool needs_id) 909 { 910 struct mptcp_pm_addr_entry *cur, *del_entry = NULL; 911 unsigned int addr_max; 912 int ret = -EINVAL; 913 914 spin_lock_bh(&pernet->lock); 915 /* to keep the code simple, don't do IDR-like allocation for address ID, 916 * just bail when we exceed limits 917 */ 918 if (pernet->next_id == MPTCP_PM_MAX_ADDR_ID) 919 pernet->next_id = 1; 920 if (pernet->addrs >= MPTCP_PM_ADDR_MAX) { 921 ret = -ERANGE; 922 goto out; 923 } 924 if (test_bit(entry->addr.id, pernet->id_bitmap)) { 925 ret = -EBUSY; 926 goto out; 927 } 928 929 /* do not insert duplicate address, differentiate on port only 930 * singled addresses 931 */ 932 if (!address_use_port(entry)) 933 entry->addr.port = 0; 934 list_for_each_entry(cur, &pernet->local_addr_list, list) { 935 if (mptcp_addresses_equal(&cur->addr, &entry->addr, 936 cur->addr.port || entry->addr.port)) { 937 /* allow replacing the exiting endpoint only if such 938 * endpoint is an implicit one and the user-space 939 * did not provide an endpoint id 940 */ 941 if (!(cur->flags & MPTCP_PM_ADDR_FLAG_IMPLICIT)) { 942 ret = -EEXIST; 943 goto out; 944 } 945 if (entry->addr.id) 946 goto out; 947 948 pernet->addrs--; 949 entry->addr.id = cur->addr.id; 950 list_del_rcu(&cur->list); 951 del_entry = cur; 952 break; 953 } 954 } 955 956 if (!entry->addr.id && needs_id) { 957 find_next: 958 entry->addr.id = find_next_zero_bit(pernet->id_bitmap, 959 MPTCP_PM_MAX_ADDR_ID + 1, 960 pernet->next_id); 961 if (!entry->addr.id && pernet->next_id != 1) { 962 pernet->next_id = 1; 963 goto find_next; 964 } 965 } 966 967 if (!entry->addr.id && needs_id) 968 goto out; 969 970 __set_bit(entry->addr.id, pernet->id_bitmap); 971 if (entry->addr.id > pernet->next_id) 972 pernet->next_id = entry->addr.id; 973 974 if (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL) { 975 addr_max = pernet->add_addr_signal_max; 976 WRITE_ONCE(pernet->add_addr_signal_max, addr_max + 1); 977 } 978 if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) { 979 addr_max = pernet->local_addr_max; 980 WRITE_ONCE(pernet->local_addr_max, addr_max + 1); 981 } 982 983 pernet->addrs++; 984 if (!entry->addr.port) 985 list_add_tail_rcu(&entry->list, &pernet->local_addr_list); 986 else 987 list_add_rcu(&entry->list, &pernet->local_addr_list); 988 ret = entry->addr.id; 989 990 out: 991 spin_unlock_bh(&pernet->lock); 992 993 /* just replaced an existing entry, free it */ 994 if (del_entry) { 995 synchronize_rcu(); 996 __mptcp_pm_release_addr_entry(del_entry); 997 } 998 return ret; 999 } 1000 1001 static struct lock_class_key mptcp_slock_keys[2]; 1002 static struct lock_class_key mptcp_keys[2]; 1003 1004 static int mptcp_pm_nl_create_listen_socket(struct sock *sk, 1005 struct mptcp_pm_addr_entry *entry) 1006 { 1007 bool is_ipv6 = sk->sk_family == AF_INET6; 1008 int addrlen = sizeof(struct sockaddr_in); 1009 struct sockaddr_storage addr; 1010 struct sock *newsk, *ssk; 1011 int backlog = 1024; 1012 int err; 1013 1014 err = sock_create_kern(sock_net(sk), entry->addr.family, 1015 SOCK_STREAM, IPPROTO_MPTCP, &entry->lsk); 1016 if (err) 1017 return err; 1018 1019 newsk = entry->lsk->sk; 1020 if (!newsk) 1021 return -EINVAL; 1022 1023 /* The subflow socket lock is acquired in a nested to the msk one 1024 * in several places, even by the TCP stack, and this msk is a kernel 1025 * socket: lockdep complains. Instead of propagating the _nested 1026 * modifiers in several places, re-init the lock class for the msk 1027 * socket to an mptcp specific one. 1028 */ 1029 sock_lock_init_class_and_name(newsk, 1030 is_ipv6 ? "mlock-AF_INET6" : "mlock-AF_INET", 1031 &mptcp_slock_keys[is_ipv6], 1032 is_ipv6 ? "msk_lock-AF_INET6" : "msk_lock-AF_INET", 1033 &mptcp_keys[is_ipv6]); 1034 1035 lock_sock(newsk); 1036 ssk = __mptcp_nmpc_sk(mptcp_sk(newsk)); 1037 release_sock(newsk); 1038 if (IS_ERR(ssk)) 1039 return PTR_ERR(ssk); 1040 1041 mptcp_info2sockaddr(&entry->addr, &addr, entry->addr.family); 1042 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1043 if (entry->addr.family == AF_INET6) 1044 addrlen = sizeof(struct sockaddr_in6); 1045 #endif 1046 if (ssk->sk_family == AF_INET) 1047 err = inet_bind_sk(ssk, (struct sockaddr *)&addr, addrlen); 1048 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1049 else if (ssk->sk_family == AF_INET6) 1050 err = inet6_bind_sk(ssk, (struct sockaddr *)&addr, addrlen); 1051 #endif 1052 if (err) 1053 return err; 1054 1055 /* We don't use mptcp_set_state() here because it needs to be called 1056 * under the msk socket lock. For the moment, that will not bring 1057 * anything more than only calling inet_sk_state_store(), because the 1058 * old status is known (TCP_CLOSE). 1059 */ 1060 inet_sk_state_store(newsk, TCP_LISTEN); 1061 lock_sock(ssk); 1062 err = __inet_listen_sk(ssk, backlog); 1063 if (!err) 1064 mptcp_event_pm_listener(ssk, MPTCP_EVENT_LISTENER_CREATED); 1065 release_sock(ssk); 1066 return err; 1067 } 1068 1069 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc) 1070 { 1071 struct mptcp_pm_addr_entry *entry; 1072 struct pm_nl_pernet *pernet; 1073 int ret = -1; 1074 1075 pernet = pm_nl_get_pernet_from_msk(msk); 1076 1077 rcu_read_lock(); 1078 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 1079 if (mptcp_addresses_equal(&entry->addr, skc, entry->addr.port)) { 1080 ret = entry->addr.id; 1081 break; 1082 } 1083 } 1084 rcu_read_unlock(); 1085 if (ret >= 0) 1086 return ret; 1087 1088 /* address not found, add to local list */ 1089 entry = kmalloc(sizeof(*entry), GFP_ATOMIC); 1090 if (!entry) 1091 return -ENOMEM; 1092 1093 entry->addr = *skc; 1094 entry->addr.id = 0; 1095 entry->addr.port = 0; 1096 entry->ifindex = 0; 1097 entry->flags = MPTCP_PM_ADDR_FLAG_IMPLICIT; 1098 entry->lsk = NULL; 1099 ret = mptcp_pm_nl_append_new_local_addr(pernet, entry, true); 1100 if (ret < 0) 1101 kfree(entry); 1102 1103 return ret; 1104 } 1105 1106 #define MPTCP_PM_CMD_GRP_OFFSET 0 1107 #define MPTCP_PM_EV_GRP_OFFSET 1 1108 1109 static const struct genl_multicast_group mptcp_pm_mcgrps[] = { 1110 [MPTCP_PM_CMD_GRP_OFFSET] = { .name = MPTCP_PM_CMD_GRP_NAME, }, 1111 [MPTCP_PM_EV_GRP_OFFSET] = { .name = MPTCP_PM_EV_GRP_NAME, 1112 .flags = GENL_MCAST_CAP_NET_ADMIN, 1113 }, 1114 }; 1115 1116 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk) 1117 { 1118 struct mptcp_subflow_context *iter, *subflow = mptcp_subflow_ctx(ssk); 1119 struct sock *sk = (struct sock *)msk; 1120 unsigned int active_max_loss_cnt; 1121 struct net *net = sock_net(sk); 1122 unsigned int stale_loss_cnt; 1123 bool slow; 1124 1125 stale_loss_cnt = mptcp_stale_loss_cnt(net); 1126 if (subflow->stale || !stale_loss_cnt || subflow->stale_count <= stale_loss_cnt) 1127 return; 1128 1129 /* look for another available subflow not in loss state */ 1130 active_max_loss_cnt = max_t(int, stale_loss_cnt - 1, 1); 1131 mptcp_for_each_subflow(msk, iter) { 1132 if (iter != subflow && mptcp_subflow_active(iter) && 1133 iter->stale_count < active_max_loss_cnt) { 1134 /* we have some alternatives, try to mark this subflow as idle ...*/ 1135 slow = lock_sock_fast(ssk); 1136 if (!tcp_rtx_and_write_queues_empty(ssk)) { 1137 subflow->stale = 1; 1138 __mptcp_retransmit_pending_data(sk); 1139 MPTCP_INC_STATS(net, MPTCP_MIB_SUBFLOWSTALE); 1140 } 1141 unlock_sock_fast(ssk, slow); 1142 1143 /* always try to push the pending data regardless of re-injections: 1144 * we can possibly use backup subflows now, and subflow selection 1145 * is cheap under the msk socket lock 1146 */ 1147 __mptcp_push_pending(sk, 0); 1148 return; 1149 } 1150 } 1151 } 1152 1153 static int mptcp_pm_family_to_addr(int family) 1154 { 1155 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1156 if (family == AF_INET6) 1157 return MPTCP_PM_ADDR_ATTR_ADDR6; 1158 #endif 1159 return MPTCP_PM_ADDR_ATTR_ADDR4; 1160 } 1161 1162 static int mptcp_pm_parse_pm_addr_attr(struct nlattr *tb[], 1163 const struct nlattr *attr, 1164 struct genl_info *info, 1165 struct mptcp_addr_info *addr, 1166 bool require_family) 1167 { 1168 int err, addr_addr; 1169 1170 if (!attr) { 1171 GENL_SET_ERR_MSG(info, "missing address info"); 1172 return -EINVAL; 1173 } 1174 1175 /* no validation needed - was already done via nested policy */ 1176 err = nla_parse_nested_deprecated(tb, MPTCP_PM_ADDR_ATTR_MAX, attr, 1177 mptcp_pm_address_nl_policy, info->extack); 1178 if (err) 1179 return err; 1180 1181 if (tb[MPTCP_PM_ADDR_ATTR_ID]) 1182 addr->id = nla_get_u8(tb[MPTCP_PM_ADDR_ATTR_ID]); 1183 1184 if (!tb[MPTCP_PM_ADDR_ATTR_FAMILY]) { 1185 if (!require_family) 1186 return 0; 1187 1188 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1189 "missing family"); 1190 return -EINVAL; 1191 } 1192 1193 addr->family = nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_FAMILY]); 1194 if (addr->family != AF_INET 1195 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1196 && addr->family != AF_INET6 1197 #endif 1198 ) { 1199 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1200 "unknown address family"); 1201 return -EINVAL; 1202 } 1203 addr_addr = mptcp_pm_family_to_addr(addr->family); 1204 if (!tb[addr_addr]) { 1205 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1206 "missing address data"); 1207 return -EINVAL; 1208 } 1209 1210 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1211 if (addr->family == AF_INET6) 1212 addr->addr6 = nla_get_in6_addr(tb[addr_addr]); 1213 else 1214 #endif 1215 addr->addr.s_addr = nla_get_in_addr(tb[addr_addr]); 1216 1217 if (tb[MPTCP_PM_ADDR_ATTR_PORT]) 1218 addr->port = htons(nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_PORT])); 1219 1220 return 0; 1221 } 1222 1223 int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info, 1224 struct mptcp_addr_info *addr) 1225 { 1226 struct nlattr *tb[MPTCP_PM_ADDR_ATTR_MAX + 1]; 1227 1228 memset(addr, 0, sizeof(*addr)); 1229 1230 return mptcp_pm_parse_pm_addr_attr(tb, attr, info, addr, true); 1231 } 1232 1233 int mptcp_pm_parse_entry(struct nlattr *attr, struct genl_info *info, 1234 bool require_family, 1235 struct mptcp_pm_addr_entry *entry) 1236 { 1237 struct nlattr *tb[MPTCP_PM_ADDR_ATTR_MAX + 1]; 1238 int err; 1239 1240 memset(entry, 0, sizeof(*entry)); 1241 1242 err = mptcp_pm_parse_pm_addr_attr(tb, attr, info, &entry->addr, require_family); 1243 if (err) 1244 return err; 1245 1246 if (tb[MPTCP_PM_ADDR_ATTR_IF_IDX]) { 1247 u32 val = nla_get_s32(tb[MPTCP_PM_ADDR_ATTR_IF_IDX]); 1248 1249 entry->ifindex = val; 1250 } 1251 1252 if (tb[MPTCP_PM_ADDR_ATTR_FLAGS]) 1253 entry->flags = nla_get_u32(tb[MPTCP_PM_ADDR_ATTR_FLAGS]); 1254 1255 if (tb[MPTCP_PM_ADDR_ATTR_PORT]) 1256 entry->addr.port = htons(nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_PORT])); 1257 1258 return 0; 1259 } 1260 1261 static struct pm_nl_pernet *genl_info_pm_nl(struct genl_info *info) 1262 { 1263 return pm_nl_get_pernet(genl_info_net(info)); 1264 } 1265 1266 static int mptcp_nl_add_subflow_or_signal_addr(struct net *net) 1267 { 1268 struct mptcp_sock *msk; 1269 long s_slot = 0, s_num = 0; 1270 1271 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1272 struct sock *sk = (struct sock *)msk; 1273 1274 if (!READ_ONCE(msk->fully_established) || 1275 mptcp_pm_is_userspace(msk)) 1276 goto next; 1277 1278 lock_sock(sk); 1279 spin_lock_bh(&msk->pm.lock); 1280 mptcp_pm_create_subflow_or_signal_addr(msk); 1281 spin_unlock_bh(&msk->pm.lock); 1282 release_sock(sk); 1283 1284 next: 1285 sock_put(sk); 1286 cond_resched(); 1287 } 1288 1289 return 0; 1290 } 1291 1292 static bool mptcp_pm_has_addr_attr_id(const struct nlattr *attr, 1293 struct genl_info *info) 1294 { 1295 struct nlattr *tb[MPTCP_PM_ADDR_ATTR_MAX + 1]; 1296 1297 if (!nla_parse_nested_deprecated(tb, MPTCP_PM_ADDR_ATTR_MAX, attr, 1298 mptcp_pm_address_nl_policy, info->extack) && 1299 tb[MPTCP_PM_ADDR_ATTR_ID]) 1300 return true; 1301 return false; 1302 } 1303 1304 int mptcp_pm_nl_add_addr_doit(struct sk_buff *skb, struct genl_info *info) 1305 { 1306 struct nlattr *attr = info->attrs[MPTCP_PM_ENDPOINT_ADDR]; 1307 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1308 struct mptcp_pm_addr_entry addr, *entry; 1309 int ret; 1310 1311 ret = mptcp_pm_parse_entry(attr, info, true, &addr); 1312 if (ret < 0) 1313 return ret; 1314 1315 if (addr.addr.port && !(addr.flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) { 1316 GENL_SET_ERR_MSG(info, "flags must have signal when using port"); 1317 return -EINVAL; 1318 } 1319 1320 if (addr.flags & MPTCP_PM_ADDR_FLAG_SIGNAL && 1321 addr.flags & MPTCP_PM_ADDR_FLAG_FULLMESH) { 1322 GENL_SET_ERR_MSG(info, "flags mustn't have both signal and fullmesh"); 1323 return -EINVAL; 1324 } 1325 1326 if (addr.flags & MPTCP_PM_ADDR_FLAG_IMPLICIT) { 1327 GENL_SET_ERR_MSG(info, "can't create IMPLICIT endpoint"); 1328 return -EINVAL; 1329 } 1330 1331 entry = kzalloc(sizeof(*entry), GFP_KERNEL_ACCOUNT); 1332 if (!entry) { 1333 GENL_SET_ERR_MSG(info, "can't allocate addr"); 1334 return -ENOMEM; 1335 } 1336 1337 *entry = addr; 1338 if (entry->addr.port) { 1339 ret = mptcp_pm_nl_create_listen_socket(skb->sk, entry); 1340 if (ret) { 1341 GENL_SET_ERR_MSG_FMT(info, "create listen socket error: %d", ret); 1342 goto out_free; 1343 } 1344 } 1345 ret = mptcp_pm_nl_append_new_local_addr(pernet, entry, 1346 !mptcp_pm_has_addr_attr_id(attr, info)); 1347 if (ret < 0) { 1348 GENL_SET_ERR_MSG_FMT(info, "too many addresses or duplicate one: %d", ret); 1349 goto out_free; 1350 } 1351 1352 mptcp_nl_add_subflow_or_signal_addr(sock_net(skb->sk)); 1353 return 0; 1354 1355 out_free: 1356 __mptcp_pm_release_addr_entry(entry); 1357 return ret; 1358 } 1359 1360 int mptcp_pm_nl_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, unsigned int id, 1361 u8 *flags, int *ifindex) 1362 { 1363 struct mptcp_pm_addr_entry *entry; 1364 struct sock *sk = (struct sock *)msk; 1365 struct net *net = sock_net(sk); 1366 1367 rcu_read_lock(); 1368 entry = __lookup_addr_by_id(pm_nl_get_pernet(net), id); 1369 if (entry) { 1370 *flags = entry->flags; 1371 *ifindex = entry->ifindex; 1372 } 1373 rcu_read_unlock(); 1374 1375 return 0; 1376 } 1377 1378 static bool remove_anno_list_by_saddr(struct mptcp_sock *msk, 1379 const struct mptcp_addr_info *addr) 1380 { 1381 struct mptcp_pm_add_entry *entry; 1382 1383 entry = mptcp_pm_del_add_timer(msk, addr, false); 1384 if (entry) { 1385 list_del(&entry->list); 1386 kfree(entry); 1387 return true; 1388 } 1389 1390 return false; 1391 } 1392 1393 static bool mptcp_pm_remove_anno_addr(struct mptcp_sock *msk, 1394 const struct mptcp_addr_info *addr, 1395 bool force) 1396 { 1397 struct mptcp_rm_list list = { .nr = 0 }; 1398 bool ret; 1399 1400 list.ids[list.nr++] = addr->id; 1401 1402 ret = remove_anno_list_by_saddr(msk, addr); 1403 if (ret || force) { 1404 spin_lock_bh(&msk->pm.lock); 1405 mptcp_pm_remove_addr(msk, &list); 1406 spin_unlock_bh(&msk->pm.lock); 1407 } 1408 return ret; 1409 } 1410 1411 static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net, 1412 const struct mptcp_pm_addr_entry *entry) 1413 { 1414 const struct mptcp_addr_info *addr = &entry->addr; 1415 struct mptcp_rm_list list = { .nr = 0 }; 1416 long s_slot = 0, s_num = 0; 1417 struct mptcp_sock *msk; 1418 1419 pr_debug("remove_id=%d", addr->id); 1420 1421 list.ids[list.nr++] = addr->id; 1422 1423 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1424 struct sock *sk = (struct sock *)msk; 1425 bool remove_subflow; 1426 1427 if (mptcp_pm_is_userspace(msk)) 1428 goto next; 1429 1430 if (list_empty(&msk->conn_list)) { 1431 mptcp_pm_remove_anno_addr(msk, addr, false); 1432 goto next; 1433 } 1434 1435 lock_sock(sk); 1436 remove_subflow = lookup_subflow_by_saddr(&msk->conn_list, addr); 1437 mptcp_pm_remove_anno_addr(msk, addr, remove_subflow && 1438 !(entry->flags & MPTCP_PM_ADDR_FLAG_IMPLICIT)); 1439 if (remove_subflow) 1440 mptcp_pm_remove_subflow(msk, &list); 1441 release_sock(sk); 1442 1443 next: 1444 sock_put(sk); 1445 cond_resched(); 1446 } 1447 1448 return 0; 1449 } 1450 1451 static int mptcp_nl_remove_id_zero_address(struct net *net, 1452 struct mptcp_addr_info *addr) 1453 { 1454 struct mptcp_rm_list list = { .nr = 0 }; 1455 long s_slot = 0, s_num = 0; 1456 struct mptcp_sock *msk; 1457 1458 list.ids[list.nr++] = 0; 1459 1460 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1461 struct sock *sk = (struct sock *)msk; 1462 struct mptcp_addr_info msk_local; 1463 1464 if (list_empty(&msk->conn_list) || mptcp_pm_is_userspace(msk)) 1465 goto next; 1466 1467 mptcp_local_address((struct sock_common *)msk, &msk_local); 1468 if (!mptcp_addresses_equal(&msk_local, addr, addr->port)) 1469 goto next; 1470 1471 lock_sock(sk); 1472 spin_lock_bh(&msk->pm.lock); 1473 mptcp_pm_remove_addr(msk, &list); 1474 mptcp_pm_nl_rm_subflow_received(msk, &list); 1475 spin_unlock_bh(&msk->pm.lock); 1476 release_sock(sk); 1477 1478 next: 1479 sock_put(sk); 1480 cond_resched(); 1481 } 1482 1483 return 0; 1484 } 1485 1486 int mptcp_pm_nl_del_addr_doit(struct sk_buff *skb, struct genl_info *info) 1487 { 1488 struct nlattr *attr = info->attrs[MPTCP_PM_ENDPOINT_ADDR]; 1489 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1490 struct mptcp_pm_addr_entry addr, *entry; 1491 unsigned int addr_max; 1492 int ret; 1493 1494 ret = mptcp_pm_parse_entry(attr, info, false, &addr); 1495 if (ret < 0) 1496 return ret; 1497 1498 /* the zero id address is special: the first address used by the msk 1499 * always gets such an id, so different subflows can have different zero 1500 * id addresses. Additionally zero id is not accounted for in id_bitmap. 1501 * Let's use an 'mptcp_rm_list' instead of the common remove code. 1502 */ 1503 if (addr.addr.id == 0) 1504 return mptcp_nl_remove_id_zero_address(sock_net(skb->sk), &addr.addr); 1505 1506 spin_lock_bh(&pernet->lock); 1507 entry = __lookup_addr_by_id(pernet, addr.addr.id); 1508 if (!entry) { 1509 GENL_SET_ERR_MSG(info, "address not found"); 1510 spin_unlock_bh(&pernet->lock); 1511 return -EINVAL; 1512 } 1513 if (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL) { 1514 addr_max = pernet->add_addr_signal_max; 1515 WRITE_ONCE(pernet->add_addr_signal_max, addr_max - 1); 1516 } 1517 if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) { 1518 addr_max = pernet->local_addr_max; 1519 WRITE_ONCE(pernet->local_addr_max, addr_max - 1); 1520 } 1521 1522 pernet->addrs--; 1523 list_del_rcu(&entry->list); 1524 __clear_bit(entry->addr.id, pernet->id_bitmap); 1525 spin_unlock_bh(&pernet->lock); 1526 1527 mptcp_nl_remove_subflow_and_signal_addr(sock_net(skb->sk), entry); 1528 synchronize_rcu(); 1529 __mptcp_pm_release_addr_entry(entry); 1530 1531 return ret; 1532 } 1533 1534 void mptcp_pm_remove_addrs(struct mptcp_sock *msk, struct list_head *rm_list) 1535 { 1536 struct mptcp_rm_list alist = { .nr = 0 }; 1537 struct mptcp_pm_addr_entry *entry; 1538 1539 list_for_each_entry(entry, rm_list, list) { 1540 if ((remove_anno_list_by_saddr(msk, &entry->addr) || 1541 lookup_subflow_by_saddr(&msk->conn_list, &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 } 1552 1553 void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk, 1554 struct list_head *rm_list) 1555 { 1556 struct mptcp_rm_list alist = { .nr = 0 }, slist = { .nr = 0 }; 1557 struct mptcp_pm_addr_entry *entry; 1558 1559 list_for_each_entry(entry, rm_list, list) { 1560 if (lookup_subflow_by_saddr(&msk->conn_list, &entry->addr) && 1561 slist.nr < MPTCP_RM_IDS_MAX) 1562 slist.ids[slist.nr++] = entry->addr.id; 1563 1564 if (remove_anno_list_by_saddr(msk, &entry->addr) && 1565 alist.nr < MPTCP_RM_IDS_MAX) 1566 alist.ids[alist.nr++] = entry->addr.id; 1567 } 1568 1569 if (alist.nr) { 1570 spin_lock_bh(&msk->pm.lock); 1571 mptcp_pm_remove_addr(msk, &alist); 1572 spin_unlock_bh(&msk->pm.lock); 1573 } 1574 if (slist.nr) 1575 mptcp_pm_remove_subflow(msk, &slist); 1576 } 1577 1578 static void mptcp_nl_remove_addrs_list(struct net *net, 1579 struct list_head *rm_list) 1580 { 1581 long s_slot = 0, s_num = 0; 1582 struct mptcp_sock *msk; 1583 1584 if (list_empty(rm_list)) 1585 return; 1586 1587 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1588 struct sock *sk = (struct sock *)msk; 1589 1590 if (!mptcp_pm_is_userspace(msk)) { 1591 lock_sock(sk); 1592 mptcp_pm_remove_addrs_and_subflows(msk, rm_list); 1593 release_sock(sk); 1594 } 1595 1596 sock_put(sk); 1597 cond_resched(); 1598 } 1599 } 1600 1601 /* caller must ensure the RCU grace period is already elapsed */ 1602 static void __flush_addrs(struct list_head *list) 1603 { 1604 while (!list_empty(list)) { 1605 struct mptcp_pm_addr_entry *cur; 1606 1607 cur = list_entry(list->next, 1608 struct mptcp_pm_addr_entry, list); 1609 list_del_rcu(&cur->list); 1610 __mptcp_pm_release_addr_entry(cur); 1611 } 1612 } 1613 1614 static void __reset_counters(struct pm_nl_pernet *pernet) 1615 { 1616 WRITE_ONCE(pernet->add_addr_signal_max, 0); 1617 WRITE_ONCE(pernet->add_addr_accept_max, 0); 1618 WRITE_ONCE(pernet->local_addr_max, 0); 1619 pernet->addrs = 0; 1620 } 1621 1622 int mptcp_pm_nl_flush_addrs_doit(struct sk_buff *skb, struct genl_info *info) 1623 { 1624 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1625 LIST_HEAD(free_list); 1626 1627 spin_lock_bh(&pernet->lock); 1628 list_splice_init(&pernet->local_addr_list, &free_list); 1629 __reset_counters(pernet); 1630 pernet->next_id = 1; 1631 bitmap_zero(pernet->id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); 1632 spin_unlock_bh(&pernet->lock); 1633 mptcp_nl_remove_addrs_list(sock_net(skb->sk), &free_list); 1634 synchronize_rcu(); 1635 __flush_addrs(&free_list); 1636 return 0; 1637 } 1638 1639 static int mptcp_nl_fill_addr(struct sk_buff *skb, 1640 struct mptcp_pm_addr_entry *entry) 1641 { 1642 struct mptcp_addr_info *addr = &entry->addr; 1643 struct nlattr *attr; 1644 1645 attr = nla_nest_start(skb, MPTCP_PM_ATTR_ADDR); 1646 if (!attr) 1647 return -EMSGSIZE; 1648 1649 if (nla_put_u16(skb, MPTCP_PM_ADDR_ATTR_FAMILY, addr->family)) 1650 goto nla_put_failure; 1651 if (nla_put_u16(skb, MPTCP_PM_ADDR_ATTR_PORT, ntohs(addr->port))) 1652 goto nla_put_failure; 1653 if (nla_put_u8(skb, MPTCP_PM_ADDR_ATTR_ID, addr->id)) 1654 goto nla_put_failure; 1655 if (nla_put_u32(skb, MPTCP_PM_ADDR_ATTR_FLAGS, entry->flags)) 1656 goto nla_put_failure; 1657 if (entry->ifindex && 1658 nla_put_s32(skb, MPTCP_PM_ADDR_ATTR_IF_IDX, entry->ifindex)) 1659 goto nla_put_failure; 1660 1661 if (addr->family == AF_INET && 1662 nla_put_in_addr(skb, MPTCP_PM_ADDR_ATTR_ADDR4, 1663 addr->addr.s_addr)) 1664 goto nla_put_failure; 1665 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1666 else if (addr->family == AF_INET6 && 1667 nla_put_in6_addr(skb, MPTCP_PM_ADDR_ATTR_ADDR6, &addr->addr6)) 1668 goto nla_put_failure; 1669 #endif 1670 nla_nest_end(skb, attr); 1671 return 0; 1672 1673 nla_put_failure: 1674 nla_nest_cancel(skb, attr); 1675 return -EMSGSIZE; 1676 } 1677 1678 int mptcp_pm_nl_get_addr_doit(struct sk_buff *skb, struct genl_info *info) 1679 { 1680 struct nlattr *attr = info->attrs[MPTCP_PM_ENDPOINT_ADDR]; 1681 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1682 struct mptcp_pm_addr_entry addr, *entry; 1683 struct sk_buff *msg; 1684 void *reply; 1685 int ret; 1686 1687 ret = mptcp_pm_parse_entry(attr, info, false, &addr); 1688 if (ret < 0) 1689 return ret; 1690 1691 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 1692 if (!msg) 1693 return -ENOMEM; 1694 1695 reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0, 1696 info->genlhdr->cmd); 1697 if (!reply) { 1698 GENL_SET_ERR_MSG(info, "not enough space in Netlink message"); 1699 ret = -EMSGSIZE; 1700 goto fail; 1701 } 1702 1703 spin_lock_bh(&pernet->lock); 1704 entry = __lookup_addr_by_id(pernet, addr.addr.id); 1705 if (!entry) { 1706 GENL_SET_ERR_MSG(info, "address not found"); 1707 ret = -EINVAL; 1708 goto unlock_fail; 1709 } 1710 1711 ret = mptcp_nl_fill_addr(msg, entry); 1712 if (ret) 1713 goto unlock_fail; 1714 1715 genlmsg_end(msg, reply); 1716 ret = genlmsg_reply(msg, info); 1717 spin_unlock_bh(&pernet->lock); 1718 return ret; 1719 1720 unlock_fail: 1721 spin_unlock_bh(&pernet->lock); 1722 1723 fail: 1724 nlmsg_free(msg); 1725 return ret; 1726 } 1727 1728 int mptcp_pm_nl_get_addr_dumpit(struct sk_buff *msg, 1729 struct netlink_callback *cb) 1730 { 1731 struct net *net = sock_net(msg->sk); 1732 struct mptcp_pm_addr_entry *entry; 1733 struct pm_nl_pernet *pernet; 1734 int id = cb->args[0]; 1735 void *hdr; 1736 int i; 1737 1738 pernet = pm_nl_get_pernet(net); 1739 1740 spin_lock_bh(&pernet->lock); 1741 for (i = id; i < MPTCP_PM_MAX_ADDR_ID + 1; i++) { 1742 if (test_bit(i, pernet->id_bitmap)) { 1743 entry = __lookup_addr_by_id(pernet, i); 1744 if (!entry) 1745 break; 1746 1747 if (entry->addr.id <= id) 1748 continue; 1749 1750 hdr = genlmsg_put(msg, NETLINK_CB(cb->skb).portid, 1751 cb->nlh->nlmsg_seq, &mptcp_genl_family, 1752 NLM_F_MULTI, MPTCP_PM_CMD_GET_ADDR); 1753 if (!hdr) 1754 break; 1755 1756 if (mptcp_nl_fill_addr(msg, entry) < 0) { 1757 genlmsg_cancel(msg, hdr); 1758 break; 1759 } 1760 1761 id = entry->addr.id; 1762 genlmsg_end(msg, hdr); 1763 } 1764 } 1765 spin_unlock_bh(&pernet->lock); 1766 1767 cb->args[0] = id; 1768 return msg->len; 1769 } 1770 1771 static int parse_limit(struct genl_info *info, int id, unsigned int *limit) 1772 { 1773 struct nlattr *attr = info->attrs[id]; 1774 1775 if (!attr) 1776 return 0; 1777 1778 *limit = nla_get_u32(attr); 1779 if (*limit > MPTCP_PM_ADDR_MAX) { 1780 GENL_SET_ERR_MSG(info, "limit greater than maximum"); 1781 return -EINVAL; 1782 } 1783 return 0; 1784 } 1785 1786 int mptcp_pm_nl_set_limits_doit(struct sk_buff *skb, struct genl_info *info) 1787 { 1788 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1789 unsigned int rcv_addrs, subflows; 1790 int ret; 1791 1792 spin_lock_bh(&pernet->lock); 1793 rcv_addrs = pernet->add_addr_accept_max; 1794 ret = parse_limit(info, MPTCP_PM_ATTR_RCV_ADD_ADDRS, &rcv_addrs); 1795 if (ret) 1796 goto unlock; 1797 1798 subflows = pernet->subflows_max; 1799 ret = parse_limit(info, MPTCP_PM_ATTR_SUBFLOWS, &subflows); 1800 if (ret) 1801 goto unlock; 1802 1803 WRITE_ONCE(pernet->add_addr_accept_max, rcv_addrs); 1804 WRITE_ONCE(pernet->subflows_max, subflows); 1805 1806 unlock: 1807 spin_unlock_bh(&pernet->lock); 1808 return ret; 1809 } 1810 1811 int mptcp_pm_nl_get_limits_doit(struct sk_buff *skb, struct genl_info *info) 1812 { 1813 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1814 struct sk_buff *msg; 1815 void *reply; 1816 1817 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 1818 if (!msg) 1819 return -ENOMEM; 1820 1821 reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0, 1822 MPTCP_PM_CMD_GET_LIMITS); 1823 if (!reply) 1824 goto fail; 1825 1826 if (nla_put_u32(msg, MPTCP_PM_ATTR_RCV_ADD_ADDRS, 1827 READ_ONCE(pernet->add_addr_accept_max))) 1828 goto fail; 1829 1830 if (nla_put_u32(msg, MPTCP_PM_ATTR_SUBFLOWS, 1831 READ_ONCE(pernet->subflows_max))) 1832 goto fail; 1833 1834 genlmsg_end(msg, reply); 1835 return genlmsg_reply(msg, info); 1836 1837 fail: 1838 GENL_SET_ERR_MSG(info, "not enough space in Netlink message"); 1839 nlmsg_free(msg); 1840 return -EMSGSIZE; 1841 } 1842 1843 static void mptcp_pm_nl_fullmesh(struct mptcp_sock *msk, 1844 struct mptcp_addr_info *addr) 1845 { 1846 struct mptcp_rm_list list = { .nr = 0 }; 1847 1848 list.ids[list.nr++] = addr->id; 1849 1850 spin_lock_bh(&msk->pm.lock); 1851 mptcp_pm_nl_rm_subflow_received(msk, &list); 1852 mptcp_pm_create_subflow_or_signal_addr(msk); 1853 spin_unlock_bh(&msk->pm.lock); 1854 } 1855 1856 static int mptcp_nl_set_flags(struct net *net, 1857 struct mptcp_addr_info *addr, 1858 u8 bkup, u8 changed) 1859 { 1860 long s_slot = 0, s_num = 0; 1861 struct mptcp_sock *msk; 1862 int ret = -EINVAL; 1863 1864 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1865 struct sock *sk = (struct sock *)msk; 1866 1867 if (list_empty(&msk->conn_list) || mptcp_pm_is_userspace(msk)) 1868 goto next; 1869 1870 lock_sock(sk); 1871 if (changed & MPTCP_PM_ADDR_FLAG_BACKUP) 1872 ret = mptcp_pm_nl_mp_prio_send_ack(msk, addr, NULL, bkup); 1873 if (changed & MPTCP_PM_ADDR_FLAG_FULLMESH) 1874 mptcp_pm_nl_fullmesh(msk, addr); 1875 release_sock(sk); 1876 1877 next: 1878 sock_put(sk); 1879 cond_resched(); 1880 } 1881 1882 return ret; 1883 } 1884 1885 int mptcp_pm_nl_set_flags(struct net *net, struct mptcp_pm_addr_entry *addr, u8 bkup) 1886 { 1887 struct pm_nl_pernet *pernet = pm_nl_get_pernet(net); 1888 u8 changed, mask = MPTCP_PM_ADDR_FLAG_BACKUP | 1889 MPTCP_PM_ADDR_FLAG_FULLMESH; 1890 struct mptcp_pm_addr_entry *entry; 1891 u8 lookup_by_id = 0; 1892 1893 if (addr->addr.family == AF_UNSPEC) { 1894 lookup_by_id = 1; 1895 if (!addr->addr.id) 1896 return -EOPNOTSUPP; 1897 } 1898 1899 spin_lock_bh(&pernet->lock); 1900 entry = __lookup_addr(pernet, &addr->addr, lookup_by_id); 1901 if (!entry) { 1902 spin_unlock_bh(&pernet->lock); 1903 return -EINVAL; 1904 } 1905 if ((addr->flags & MPTCP_PM_ADDR_FLAG_FULLMESH) && 1906 (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) { 1907 spin_unlock_bh(&pernet->lock); 1908 return -EINVAL; 1909 } 1910 1911 changed = (addr->flags ^ entry->flags) & mask; 1912 entry->flags = (entry->flags & ~mask) | (addr->flags & mask); 1913 *addr = *entry; 1914 spin_unlock_bh(&pernet->lock); 1915 1916 mptcp_nl_set_flags(net, &addr->addr, bkup, changed); 1917 return 0; 1918 } 1919 1920 int mptcp_pm_nl_set_flags_doit(struct sk_buff *skb, struct genl_info *info) 1921 { 1922 struct mptcp_pm_addr_entry remote = { .addr = { .family = AF_UNSPEC }, }; 1923 struct mptcp_pm_addr_entry addr = { .addr = { .family = AF_UNSPEC }, }; 1924 struct nlattr *attr_rem = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE]; 1925 struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN]; 1926 struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR]; 1927 struct net *net = sock_net(skb->sk); 1928 u8 bkup = 0; 1929 int ret; 1930 1931 ret = mptcp_pm_parse_entry(attr, info, false, &addr); 1932 if (ret < 0) 1933 return ret; 1934 1935 if (attr_rem) { 1936 ret = mptcp_pm_parse_entry(attr_rem, info, false, &remote); 1937 if (ret < 0) 1938 return ret; 1939 } 1940 1941 if (addr.flags & MPTCP_PM_ADDR_FLAG_BACKUP) 1942 bkup = 1; 1943 1944 return mptcp_pm_set_flags(net, token, &addr, &remote, bkup); 1945 } 1946 1947 static void mptcp_nl_mcast_send(struct net *net, struct sk_buff *nlskb, gfp_t gfp) 1948 { 1949 genlmsg_multicast_netns(&mptcp_genl_family, net, 1950 nlskb, 0, MPTCP_PM_EV_GRP_OFFSET, gfp); 1951 } 1952 1953 bool mptcp_userspace_pm_active(const struct mptcp_sock *msk) 1954 { 1955 return genl_has_listeners(&mptcp_genl_family, 1956 sock_net((const struct sock *)msk), 1957 MPTCP_PM_EV_GRP_OFFSET); 1958 } 1959 1960 static int mptcp_event_add_subflow(struct sk_buff *skb, const struct sock *ssk) 1961 { 1962 const struct inet_sock *issk = inet_sk(ssk); 1963 const struct mptcp_subflow_context *sf; 1964 1965 if (nla_put_u16(skb, MPTCP_ATTR_FAMILY, ssk->sk_family)) 1966 return -EMSGSIZE; 1967 1968 switch (ssk->sk_family) { 1969 case AF_INET: 1970 if (nla_put_in_addr(skb, MPTCP_ATTR_SADDR4, issk->inet_saddr)) 1971 return -EMSGSIZE; 1972 if (nla_put_in_addr(skb, MPTCP_ATTR_DADDR4, issk->inet_daddr)) 1973 return -EMSGSIZE; 1974 break; 1975 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1976 case AF_INET6: { 1977 const struct ipv6_pinfo *np = inet6_sk(ssk); 1978 1979 if (nla_put_in6_addr(skb, MPTCP_ATTR_SADDR6, &np->saddr)) 1980 return -EMSGSIZE; 1981 if (nla_put_in6_addr(skb, MPTCP_ATTR_DADDR6, &ssk->sk_v6_daddr)) 1982 return -EMSGSIZE; 1983 break; 1984 } 1985 #endif 1986 default: 1987 WARN_ON_ONCE(1); 1988 return -EMSGSIZE; 1989 } 1990 1991 if (nla_put_be16(skb, MPTCP_ATTR_SPORT, issk->inet_sport)) 1992 return -EMSGSIZE; 1993 if (nla_put_be16(skb, MPTCP_ATTR_DPORT, issk->inet_dport)) 1994 return -EMSGSIZE; 1995 1996 sf = mptcp_subflow_ctx(ssk); 1997 if (WARN_ON_ONCE(!sf)) 1998 return -EINVAL; 1999 2000 if (nla_put_u8(skb, MPTCP_ATTR_LOC_ID, subflow_get_local_id(sf))) 2001 return -EMSGSIZE; 2002 2003 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, sf->remote_id)) 2004 return -EMSGSIZE; 2005 2006 return 0; 2007 } 2008 2009 static int mptcp_event_put_token_and_ssk(struct sk_buff *skb, 2010 const struct mptcp_sock *msk, 2011 const struct sock *ssk) 2012 { 2013 const struct sock *sk = (const struct sock *)msk; 2014 const struct mptcp_subflow_context *sf; 2015 u8 sk_err; 2016 2017 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token)) 2018 return -EMSGSIZE; 2019 2020 if (mptcp_event_add_subflow(skb, ssk)) 2021 return -EMSGSIZE; 2022 2023 sf = mptcp_subflow_ctx(ssk); 2024 if (WARN_ON_ONCE(!sf)) 2025 return -EINVAL; 2026 2027 if (nla_put_u8(skb, MPTCP_ATTR_BACKUP, sf->backup)) 2028 return -EMSGSIZE; 2029 2030 if (ssk->sk_bound_dev_if && 2031 nla_put_s32(skb, MPTCP_ATTR_IF_IDX, ssk->sk_bound_dev_if)) 2032 return -EMSGSIZE; 2033 2034 sk_err = READ_ONCE(ssk->sk_err); 2035 if (sk_err && sk->sk_state == TCP_ESTABLISHED && 2036 nla_put_u8(skb, MPTCP_ATTR_ERROR, sk_err)) 2037 return -EMSGSIZE; 2038 2039 return 0; 2040 } 2041 2042 static int mptcp_event_sub_established(struct sk_buff *skb, 2043 const struct mptcp_sock *msk, 2044 const struct sock *ssk) 2045 { 2046 return mptcp_event_put_token_and_ssk(skb, msk, ssk); 2047 } 2048 2049 static int mptcp_event_sub_closed(struct sk_buff *skb, 2050 const struct mptcp_sock *msk, 2051 const struct sock *ssk) 2052 { 2053 const struct mptcp_subflow_context *sf; 2054 2055 if (mptcp_event_put_token_and_ssk(skb, msk, ssk)) 2056 return -EMSGSIZE; 2057 2058 sf = mptcp_subflow_ctx(ssk); 2059 if (!sf->reset_seen) 2060 return 0; 2061 2062 if (nla_put_u32(skb, MPTCP_ATTR_RESET_REASON, sf->reset_reason)) 2063 return -EMSGSIZE; 2064 2065 if (nla_put_u32(skb, MPTCP_ATTR_RESET_FLAGS, sf->reset_transient)) 2066 return -EMSGSIZE; 2067 2068 return 0; 2069 } 2070 2071 static int mptcp_event_created(struct sk_buff *skb, 2072 const struct mptcp_sock *msk, 2073 const struct sock *ssk) 2074 { 2075 int err = nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token); 2076 2077 if (err) 2078 return err; 2079 2080 if (nla_put_u8(skb, MPTCP_ATTR_SERVER_SIDE, READ_ONCE(msk->pm.server_side))) 2081 return -EMSGSIZE; 2082 2083 return mptcp_event_add_subflow(skb, ssk); 2084 } 2085 2086 void mptcp_event_addr_removed(const struct mptcp_sock *msk, uint8_t id) 2087 { 2088 struct net *net = sock_net((const struct sock *)msk); 2089 struct nlmsghdr *nlh; 2090 struct sk_buff *skb; 2091 2092 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2093 return; 2094 2095 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); 2096 if (!skb) 2097 return; 2098 2099 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, MPTCP_EVENT_REMOVED); 2100 if (!nlh) 2101 goto nla_put_failure; 2102 2103 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token)) 2104 goto nla_put_failure; 2105 2106 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, id)) 2107 goto nla_put_failure; 2108 2109 genlmsg_end(skb, nlh); 2110 mptcp_nl_mcast_send(net, skb, GFP_ATOMIC); 2111 return; 2112 2113 nla_put_failure: 2114 nlmsg_free(skb); 2115 } 2116 2117 void mptcp_event_addr_announced(const struct sock *ssk, 2118 const struct mptcp_addr_info *info) 2119 { 2120 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 2121 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 2122 struct net *net = sock_net(ssk); 2123 struct nlmsghdr *nlh; 2124 struct sk_buff *skb; 2125 2126 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2127 return; 2128 2129 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); 2130 if (!skb) 2131 return; 2132 2133 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, 2134 MPTCP_EVENT_ANNOUNCED); 2135 if (!nlh) 2136 goto nla_put_failure; 2137 2138 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token)) 2139 goto nla_put_failure; 2140 2141 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, info->id)) 2142 goto nla_put_failure; 2143 2144 if (nla_put_be16(skb, MPTCP_ATTR_DPORT, 2145 info->port == 0 ? 2146 inet_sk(ssk)->inet_dport : 2147 info->port)) 2148 goto nla_put_failure; 2149 2150 switch (info->family) { 2151 case AF_INET: 2152 if (nla_put_in_addr(skb, MPTCP_ATTR_DADDR4, info->addr.s_addr)) 2153 goto nla_put_failure; 2154 break; 2155 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 2156 case AF_INET6: 2157 if (nla_put_in6_addr(skb, MPTCP_ATTR_DADDR6, &info->addr6)) 2158 goto nla_put_failure; 2159 break; 2160 #endif 2161 default: 2162 WARN_ON_ONCE(1); 2163 goto nla_put_failure; 2164 } 2165 2166 genlmsg_end(skb, nlh); 2167 mptcp_nl_mcast_send(net, skb, GFP_ATOMIC); 2168 return; 2169 2170 nla_put_failure: 2171 nlmsg_free(skb); 2172 } 2173 2174 void mptcp_event_pm_listener(const struct sock *ssk, 2175 enum mptcp_event_type event) 2176 { 2177 const struct inet_sock *issk = inet_sk(ssk); 2178 struct net *net = sock_net(ssk); 2179 struct nlmsghdr *nlh; 2180 struct sk_buff *skb; 2181 2182 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2183 return; 2184 2185 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 2186 if (!skb) 2187 return; 2188 2189 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, event); 2190 if (!nlh) 2191 goto nla_put_failure; 2192 2193 if (nla_put_u16(skb, MPTCP_ATTR_FAMILY, ssk->sk_family)) 2194 goto nla_put_failure; 2195 2196 if (nla_put_be16(skb, MPTCP_ATTR_SPORT, issk->inet_sport)) 2197 goto nla_put_failure; 2198 2199 switch (ssk->sk_family) { 2200 case AF_INET: 2201 if (nla_put_in_addr(skb, MPTCP_ATTR_SADDR4, issk->inet_saddr)) 2202 goto nla_put_failure; 2203 break; 2204 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 2205 case AF_INET6: { 2206 const struct ipv6_pinfo *np = inet6_sk(ssk); 2207 2208 if (nla_put_in6_addr(skb, MPTCP_ATTR_SADDR6, &np->saddr)) 2209 goto nla_put_failure; 2210 break; 2211 } 2212 #endif 2213 default: 2214 WARN_ON_ONCE(1); 2215 goto nla_put_failure; 2216 } 2217 2218 genlmsg_end(skb, nlh); 2219 mptcp_nl_mcast_send(net, skb, GFP_KERNEL); 2220 return; 2221 2222 nla_put_failure: 2223 nlmsg_free(skb); 2224 } 2225 2226 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk, 2227 const struct sock *ssk, gfp_t gfp) 2228 { 2229 struct net *net = sock_net((const struct sock *)msk); 2230 struct nlmsghdr *nlh; 2231 struct sk_buff *skb; 2232 2233 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2234 return; 2235 2236 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, gfp); 2237 if (!skb) 2238 return; 2239 2240 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, type); 2241 if (!nlh) 2242 goto nla_put_failure; 2243 2244 switch (type) { 2245 case MPTCP_EVENT_UNSPEC: 2246 WARN_ON_ONCE(1); 2247 break; 2248 case MPTCP_EVENT_CREATED: 2249 case MPTCP_EVENT_ESTABLISHED: 2250 if (mptcp_event_created(skb, msk, ssk) < 0) 2251 goto nla_put_failure; 2252 break; 2253 case MPTCP_EVENT_CLOSED: 2254 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token) < 0) 2255 goto nla_put_failure; 2256 break; 2257 case MPTCP_EVENT_ANNOUNCED: 2258 case MPTCP_EVENT_REMOVED: 2259 /* call mptcp_event_addr_announced()/removed instead */ 2260 WARN_ON_ONCE(1); 2261 break; 2262 case MPTCP_EVENT_SUB_ESTABLISHED: 2263 case MPTCP_EVENT_SUB_PRIORITY: 2264 if (mptcp_event_sub_established(skb, msk, ssk) < 0) 2265 goto nla_put_failure; 2266 break; 2267 case MPTCP_EVENT_SUB_CLOSED: 2268 if (mptcp_event_sub_closed(skb, msk, ssk) < 0) 2269 goto nla_put_failure; 2270 break; 2271 case MPTCP_EVENT_LISTENER_CREATED: 2272 case MPTCP_EVENT_LISTENER_CLOSED: 2273 break; 2274 } 2275 2276 genlmsg_end(skb, nlh); 2277 mptcp_nl_mcast_send(net, skb, gfp); 2278 return; 2279 2280 nla_put_failure: 2281 nlmsg_free(skb); 2282 } 2283 2284 static struct genl_family mptcp_genl_family __ro_after_init = { 2285 .name = MPTCP_PM_NAME, 2286 .version = MPTCP_PM_VER, 2287 .netnsok = true, 2288 .module = THIS_MODULE, 2289 .ops = mptcp_pm_nl_ops, 2290 .n_ops = ARRAY_SIZE(mptcp_pm_nl_ops), 2291 .resv_start_op = MPTCP_PM_CMD_SUBFLOW_DESTROY + 1, 2292 .mcgrps = mptcp_pm_mcgrps, 2293 .n_mcgrps = ARRAY_SIZE(mptcp_pm_mcgrps), 2294 }; 2295 2296 static int __net_init pm_nl_init_net(struct net *net) 2297 { 2298 struct pm_nl_pernet *pernet = pm_nl_get_pernet(net); 2299 2300 INIT_LIST_HEAD_RCU(&pernet->local_addr_list); 2301 2302 /* Cit. 2 subflows ought to be enough for anybody. */ 2303 pernet->subflows_max = 2; 2304 pernet->next_id = 1; 2305 pernet->stale_loss_cnt = 4; 2306 spin_lock_init(&pernet->lock); 2307 2308 /* No need to initialize other pernet fields, the struct is zeroed at 2309 * allocation time. 2310 */ 2311 2312 return 0; 2313 } 2314 2315 static void __net_exit pm_nl_exit_net(struct list_head *net_list) 2316 { 2317 struct net *net; 2318 2319 list_for_each_entry(net, net_list, exit_list) { 2320 struct pm_nl_pernet *pernet = pm_nl_get_pernet(net); 2321 2322 /* net is removed from namespace list, can't race with 2323 * other modifiers, also netns core already waited for a 2324 * RCU grace period. 2325 */ 2326 __flush_addrs(&pernet->local_addr_list); 2327 } 2328 } 2329 2330 static struct pernet_operations mptcp_pm_pernet_ops = { 2331 .init = pm_nl_init_net, 2332 .exit_batch = pm_nl_exit_net, 2333 .id = &pm_nl_pernet_id, 2334 .size = sizeof(struct pm_nl_pernet), 2335 }; 2336 2337 void __init mptcp_pm_nl_init(void) 2338 { 2339 if (register_pernet_subsys(&mptcp_pm_pernet_ops) < 0) 2340 panic("Failed to register MPTCP PM pernet subsystem.\n"); 2341 2342 if (genl_register_family(&mptcp_genl_family)) 2343 panic("Failed to register MPTCP PM netlink family\n"); 2344 } 2345