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/netns/generic.h> 13 #include <net/mptcp.h> 14 #include <net/genetlink.h> 15 #include <uapi/linux/mptcp.h> 16 17 #include "protocol.h" 18 #include "mib.h" 19 20 /* forward declaration */ 21 static struct genl_family mptcp_genl_family; 22 23 static int pm_nl_pernet_id; 24 25 struct mptcp_pm_add_entry { 26 struct list_head list; 27 struct mptcp_addr_info addr; 28 struct timer_list add_timer; 29 struct mptcp_sock *sock; 30 u8 retrans_times; 31 }; 32 33 struct pm_nl_pernet { 34 /* protects pernet updates */ 35 spinlock_t lock; 36 struct list_head local_addr_list; 37 unsigned int addrs; 38 unsigned int stale_loss_cnt; 39 unsigned int add_addr_signal_max; 40 unsigned int add_addr_accept_max; 41 unsigned int local_addr_max; 42 unsigned int subflows_max; 43 unsigned int next_id; 44 DECLARE_BITMAP(id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); 45 }; 46 47 #define MPTCP_PM_ADDR_MAX 8 48 #define ADD_ADDR_RETRANS_MAX 3 49 50 static struct pm_nl_pernet *pm_nl_get_pernet(const struct net *net) 51 { 52 return net_generic(net, pm_nl_pernet_id); 53 } 54 55 static struct pm_nl_pernet * 56 pm_nl_get_pernet_from_msk(const struct mptcp_sock *msk) 57 { 58 return pm_nl_get_pernet(sock_net((struct sock *)msk)); 59 } 60 61 bool mptcp_addresses_equal(const struct mptcp_addr_info *a, 62 const struct mptcp_addr_info *b, bool use_port) 63 { 64 bool addr_equals = false; 65 66 if (a->family == b->family) { 67 if (a->family == AF_INET) 68 addr_equals = a->addr.s_addr == b->addr.s_addr; 69 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 70 else 71 addr_equals = !ipv6_addr_cmp(&a->addr6, &b->addr6); 72 } else if (a->family == AF_INET) { 73 if (ipv6_addr_v4mapped(&b->addr6)) 74 addr_equals = a->addr.s_addr == b->addr6.s6_addr32[3]; 75 } else if (b->family == AF_INET) { 76 if (ipv6_addr_v4mapped(&a->addr6)) 77 addr_equals = a->addr6.s6_addr32[3] == b->addr.s_addr; 78 #endif 79 } 80 81 if (!addr_equals) 82 return false; 83 if (!use_port) 84 return true; 85 86 return a->port == b->port; 87 } 88 89 static void local_address(const struct sock_common *skc, 90 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 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 const struct sock *sk = (const struct sock *)msk; 156 struct mptcp_pm_addr_entry *entry, *ret = NULL; 157 158 msk_owned_by_me(msk); 159 160 rcu_read_lock(); 161 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 162 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW)) 163 continue; 164 165 if (!test_bit(entry->addr.id, msk->pm.id_avail_bitmap)) 166 continue; 167 168 if (entry->addr.family != sk->sk_family) { 169 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 170 if ((entry->addr.family == AF_INET && 171 !ipv6_addr_v4mapped(&sk->sk_v6_daddr)) || 172 (sk->sk_family == AF_INET && 173 !ipv6_addr_v4mapped(&entry->addr.addr6))) 174 #endif 175 continue; 176 } 177 178 ret = entry; 179 break; 180 } 181 rcu_read_unlock(); 182 return ret; 183 } 184 185 static struct mptcp_pm_addr_entry * 186 select_signal_address(struct pm_nl_pernet *pernet, const struct mptcp_sock *msk) 187 { 188 struct mptcp_pm_addr_entry *entry, *ret = NULL; 189 190 rcu_read_lock(); 191 /* do not keep any additional per socket state, just signal 192 * the address list in order. 193 * Note: removal from the local address list during the msk life-cycle 194 * can lead to additional addresses not being announced. 195 */ 196 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 197 if (!test_bit(entry->addr.id, msk->pm.id_avail_bitmap)) 198 continue; 199 200 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) 201 continue; 202 203 ret = entry; 204 break; 205 } 206 rcu_read_unlock(); 207 return ret; 208 } 209 210 unsigned int mptcp_pm_get_add_addr_signal_max(const struct mptcp_sock *msk) 211 { 212 const struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk); 213 214 return READ_ONCE(pernet->add_addr_signal_max); 215 } 216 EXPORT_SYMBOL_GPL(mptcp_pm_get_add_addr_signal_max); 217 218 unsigned int mptcp_pm_get_add_addr_accept_max(const struct mptcp_sock *msk) 219 { 220 struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk); 221 222 return READ_ONCE(pernet->add_addr_accept_max); 223 } 224 EXPORT_SYMBOL_GPL(mptcp_pm_get_add_addr_accept_max); 225 226 unsigned int mptcp_pm_get_subflows_max(const struct mptcp_sock *msk) 227 { 228 struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk); 229 230 return READ_ONCE(pernet->subflows_max); 231 } 232 EXPORT_SYMBOL_GPL(mptcp_pm_get_subflows_max); 233 234 unsigned int mptcp_pm_get_local_addr_max(const struct mptcp_sock *msk) 235 { 236 struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk); 237 238 return READ_ONCE(pernet->local_addr_max); 239 } 240 EXPORT_SYMBOL_GPL(mptcp_pm_get_local_addr_max); 241 242 bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk) 243 { 244 struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk); 245 246 if (msk->pm.subflows == mptcp_pm_get_subflows_max(msk) || 247 (find_next_and_bit(pernet->id_bitmap, msk->pm.id_avail_bitmap, 248 MPTCP_PM_MAX_ADDR_ID + 1, 0) == MPTCP_PM_MAX_ADDR_ID + 1)) { 249 WRITE_ONCE(msk->pm.work_pending, false); 250 return false; 251 } 252 return true; 253 } 254 255 struct mptcp_pm_add_entry * 256 mptcp_lookup_anno_list_by_saddr(const struct mptcp_sock *msk, 257 const struct mptcp_addr_info *addr) 258 { 259 struct mptcp_pm_add_entry *entry; 260 261 lockdep_assert_held(&msk->pm.lock); 262 263 list_for_each_entry(entry, &msk->pm.anno_list, list) { 264 if (mptcp_addresses_equal(&entry->addr, addr, true)) 265 return entry; 266 } 267 268 return NULL; 269 } 270 271 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk) 272 { 273 struct mptcp_pm_add_entry *entry; 274 struct mptcp_addr_info saddr; 275 bool ret = false; 276 277 local_address((struct sock_common *)sk, &saddr); 278 279 spin_lock_bh(&msk->pm.lock); 280 list_for_each_entry(entry, &msk->pm.anno_list, list) { 281 if (mptcp_addresses_equal(&entry->addr, &saddr, true)) { 282 ret = true; 283 goto out; 284 } 285 } 286 287 out: 288 spin_unlock_bh(&msk->pm.lock); 289 return ret; 290 } 291 292 static void mptcp_pm_add_timer(struct timer_list *timer) 293 { 294 struct mptcp_pm_add_entry *entry = from_timer(entry, timer, add_timer); 295 struct mptcp_sock *msk = entry->sock; 296 struct sock *sk = (struct sock *)msk; 297 298 pr_debug("msk=%p", msk); 299 300 if (!msk) 301 return; 302 303 if (inet_sk_state_load(sk) == TCP_CLOSE) 304 return; 305 306 if (!entry->addr.id) 307 return; 308 309 if (mptcp_pm_should_add_signal_addr(msk)) { 310 sk_reset_timer(sk, timer, jiffies + TCP_RTO_MAX / 8); 311 goto out; 312 } 313 314 spin_lock_bh(&msk->pm.lock); 315 316 if (!mptcp_pm_should_add_signal_addr(msk)) { 317 pr_debug("retransmit ADD_ADDR id=%d", entry->addr.id); 318 mptcp_pm_announce_addr(msk, &entry->addr, false); 319 mptcp_pm_add_addr_send_ack(msk); 320 entry->retrans_times++; 321 } 322 323 if (entry->retrans_times < ADD_ADDR_RETRANS_MAX) 324 sk_reset_timer(sk, timer, 325 jiffies + mptcp_get_add_addr_timeout(sock_net(sk))); 326 327 spin_unlock_bh(&msk->pm.lock); 328 329 if (entry->retrans_times == ADD_ADDR_RETRANS_MAX) 330 mptcp_pm_subflow_established(msk); 331 332 out: 333 __sock_put(sk); 334 } 335 336 struct mptcp_pm_add_entry * 337 mptcp_pm_del_add_timer(struct mptcp_sock *msk, 338 const struct mptcp_addr_info *addr, bool check_id) 339 { 340 struct mptcp_pm_add_entry *entry; 341 struct sock *sk = (struct sock *)msk; 342 343 spin_lock_bh(&msk->pm.lock); 344 entry = mptcp_lookup_anno_list_by_saddr(msk, addr); 345 if (entry && (!check_id || entry->addr.id == addr->id)) 346 entry->retrans_times = ADD_ADDR_RETRANS_MAX; 347 spin_unlock_bh(&msk->pm.lock); 348 349 if (entry && (!check_id || entry->addr.id == addr->id)) 350 sk_stop_timer_sync(sk, &entry->add_timer); 351 352 return entry; 353 } 354 355 bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk, 356 const struct mptcp_pm_addr_entry *entry) 357 { 358 struct mptcp_pm_add_entry *add_entry = NULL; 359 struct sock *sk = (struct sock *)msk; 360 struct net *net = sock_net(sk); 361 362 lockdep_assert_held(&msk->pm.lock); 363 364 add_entry = mptcp_lookup_anno_list_by_saddr(msk, &entry->addr); 365 366 if (add_entry) { 367 if (mptcp_pm_is_kernel(msk)) 368 return false; 369 370 sk_reset_timer(sk, &add_entry->add_timer, 371 jiffies + mptcp_get_add_addr_timeout(net)); 372 return true; 373 } 374 375 add_entry = kmalloc(sizeof(*add_entry), GFP_ATOMIC); 376 if (!add_entry) 377 return false; 378 379 list_add(&add_entry->list, &msk->pm.anno_list); 380 381 add_entry->addr = entry->addr; 382 add_entry->sock = msk; 383 add_entry->retrans_times = 0; 384 385 timer_setup(&add_entry->add_timer, mptcp_pm_add_timer, 0); 386 sk_reset_timer(sk, &add_entry->add_timer, 387 jiffies + mptcp_get_add_addr_timeout(net)); 388 389 return true; 390 } 391 392 void mptcp_pm_free_anno_list(struct mptcp_sock *msk) 393 { 394 struct mptcp_pm_add_entry *entry, *tmp; 395 struct sock *sk = (struct sock *)msk; 396 LIST_HEAD(free_list); 397 398 pr_debug("msk=%p", msk); 399 400 spin_lock_bh(&msk->pm.lock); 401 list_splice_init(&msk->pm.anno_list, &free_list); 402 spin_unlock_bh(&msk->pm.lock); 403 404 list_for_each_entry_safe(entry, tmp, &free_list, list) { 405 sk_stop_timer_sync(sk, &entry->add_timer); 406 kfree(entry); 407 } 408 } 409 410 static bool lookup_address_in_vec(const struct mptcp_addr_info *addrs, unsigned int nr, 411 const struct mptcp_addr_info *addr) 412 { 413 int i; 414 415 for (i = 0; i < nr; i++) { 416 if (addrs[i].id == addr->id) 417 return true; 418 } 419 420 return false; 421 } 422 423 /* Fill all the remote addresses into the array addrs[], 424 * and return the array size. 425 */ 426 static unsigned int fill_remote_addresses_vec(struct mptcp_sock *msk, bool fullmesh, 427 struct mptcp_addr_info *addrs) 428 { 429 bool deny_id0 = READ_ONCE(msk->pm.remote_deny_join_id0); 430 struct sock *sk = (struct sock *)msk, *ssk; 431 struct mptcp_subflow_context *subflow; 432 struct mptcp_addr_info remote = { 0 }; 433 unsigned int subflows_max; 434 int i = 0; 435 436 subflows_max = mptcp_pm_get_subflows_max(msk); 437 remote_address((struct sock_common *)sk, &remote); 438 439 /* Non-fullmesh endpoint, fill in the single entry 440 * corresponding to the primary MPC subflow remote address 441 */ 442 if (!fullmesh) { 443 if (deny_id0) 444 return 0; 445 446 msk->pm.subflows++; 447 addrs[i++] = remote; 448 } else { 449 mptcp_for_each_subflow(msk, subflow) { 450 ssk = mptcp_subflow_tcp_sock(subflow); 451 remote_address((struct sock_common *)ssk, &addrs[i]); 452 addrs[i].id = subflow->remote_id; 453 if (deny_id0 && !addrs[i].id) 454 continue; 455 456 if (!lookup_address_in_vec(addrs, i, &addrs[i]) && 457 msk->pm.subflows < subflows_max) { 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 if (subflow->backup != backup) 479 msk->last_snd = NULL; 480 481 subflow->send_mp_prio = 1; 482 subflow->backup = backup; 483 subflow->request_bkup = backup; 484 } 485 486 __mptcp_subflow_send_ack(ssk); 487 unlock_sock_fast(ssk, slow); 488 } 489 490 static void mptcp_pm_send_ack(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow, 491 bool prio, bool backup) 492 { 493 spin_unlock_bh(&msk->pm.lock); 494 __mptcp_pm_send_ack(msk, subflow, prio, backup); 495 spin_lock_bh(&msk->pm.lock); 496 } 497 498 static struct mptcp_pm_addr_entry * 499 __lookup_addr_by_id(struct pm_nl_pernet *pernet, unsigned int id) 500 { 501 struct mptcp_pm_addr_entry *entry; 502 503 list_for_each_entry(entry, &pernet->local_addr_list, list) { 504 if (entry->addr.id == id) 505 return entry; 506 } 507 return NULL; 508 } 509 510 static struct mptcp_pm_addr_entry * 511 __lookup_addr(struct pm_nl_pernet *pernet, const struct mptcp_addr_info *info, 512 bool lookup_by_id) 513 { 514 struct mptcp_pm_addr_entry *entry; 515 516 list_for_each_entry(entry, &pernet->local_addr_list, list) { 517 if ((!lookup_by_id && 518 mptcp_addresses_equal(&entry->addr, info, entry->addr.port)) || 519 (lookup_by_id && entry->addr.id == info->id)) 520 return entry; 521 } 522 return NULL; 523 } 524 525 static void mptcp_pm_create_subflow_or_signal_addr(struct mptcp_sock *msk) 526 { 527 struct sock *sk = (struct sock *)msk; 528 struct mptcp_pm_addr_entry *local; 529 unsigned int add_addr_signal_max; 530 unsigned int local_addr_max; 531 struct pm_nl_pernet *pernet; 532 unsigned int subflows_max; 533 534 pernet = pm_nl_get_pernet(sock_net(sk)); 535 536 add_addr_signal_max = mptcp_pm_get_add_addr_signal_max(msk); 537 local_addr_max = mptcp_pm_get_local_addr_max(msk); 538 subflows_max = mptcp_pm_get_subflows_max(msk); 539 540 /* do lazy endpoint usage accounting for the MPC subflows */ 541 if (unlikely(!(msk->pm.status & BIT(MPTCP_PM_MPC_ENDPOINT_ACCOUNTED))) && msk->first) { 542 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(msk->first); 543 struct mptcp_pm_addr_entry *entry; 544 struct mptcp_addr_info mpc_addr; 545 bool backup = false; 546 547 local_address((struct sock_common *)msk->first, &mpc_addr); 548 rcu_read_lock(); 549 entry = __lookup_addr(pernet, &mpc_addr, false); 550 if (entry) { 551 __clear_bit(entry->addr.id, msk->pm.id_avail_bitmap); 552 msk->mpc_endpoint_id = entry->addr.id; 553 backup = !!(entry->flags & MPTCP_PM_ADDR_FLAG_BACKUP); 554 } 555 rcu_read_unlock(); 556 557 if (backup) 558 mptcp_pm_send_ack(msk, subflow, true, backup); 559 560 msk->pm.status |= BIT(MPTCP_PM_MPC_ENDPOINT_ACCOUNTED); 561 } 562 563 pr_debug("local %d:%d signal %d:%d subflows %d:%d\n", 564 msk->pm.local_addr_used, local_addr_max, 565 msk->pm.add_addr_signaled, add_addr_signal_max, 566 msk->pm.subflows, subflows_max); 567 568 /* check first for announce */ 569 if (msk->pm.add_addr_signaled < add_addr_signal_max) { 570 local = select_signal_address(pernet, msk); 571 572 /* due to racing events on both ends we can reach here while 573 * previous add address is still running: if we invoke now 574 * mptcp_pm_announce_addr(), that will fail and the 575 * corresponding id will be marked as used. 576 * Instead let the PM machinery reschedule us when the 577 * current address announce will be completed. 578 */ 579 if (msk->pm.addr_signal & BIT(MPTCP_ADD_ADDR_SIGNAL)) 580 return; 581 582 if (local) { 583 if (mptcp_pm_alloc_anno_list(msk, local)) { 584 __clear_bit(local->addr.id, msk->pm.id_avail_bitmap); 585 msk->pm.add_addr_signaled++; 586 mptcp_pm_announce_addr(msk, &local->addr, false); 587 mptcp_pm_nl_addr_send_ack(msk); 588 } 589 } 590 } 591 592 /* check if should create a new subflow */ 593 while (msk->pm.local_addr_used < local_addr_max && 594 msk->pm.subflows < subflows_max) { 595 struct mptcp_addr_info addrs[MPTCP_PM_ADDR_MAX]; 596 bool fullmesh; 597 int i, nr; 598 599 local = select_local_address(pernet, msk); 600 if (!local) 601 break; 602 603 fullmesh = !!(local->flags & MPTCP_PM_ADDR_FLAG_FULLMESH); 604 605 msk->pm.local_addr_used++; 606 nr = fill_remote_addresses_vec(msk, fullmesh, addrs); 607 if (nr) 608 __clear_bit(local->addr.id, msk->pm.id_avail_bitmap); 609 spin_unlock_bh(&msk->pm.lock); 610 for (i = 0; i < nr; i++) 611 __mptcp_subflow_connect(sk, &local->addr, &addrs[i]); 612 spin_lock_bh(&msk->pm.lock); 613 } 614 mptcp_pm_nl_check_work_pending(msk); 615 } 616 617 static void mptcp_pm_nl_fully_established(struct mptcp_sock *msk) 618 { 619 mptcp_pm_create_subflow_or_signal_addr(msk); 620 } 621 622 static void mptcp_pm_nl_subflow_established(struct mptcp_sock *msk) 623 { 624 mptcp_pm_create_subflow_or_signal_addr(msk); 625 } 626 627 /* Fill all the local addresses into the array addrs[], 628 * and return the array size. 629 */ 630 static unsigned int fill_local_addresses_vec(struct mptcp_sock *msk, 631 struct mptcp_addr_info *addrs) 632 { 633 struct sock *sk = (struct sock *)msk; 634 struct mptcp_pm_addr_entry *entry; 635 struct mptcp_addr_info local; 636 struct pm_nl_pernet *pernet; 637 unsigned int subflows_max; 638 int i = 0; 639 640 pernet = pm_nl_get_pernet_from_msk(msk); 641 subflows_max = mptcp_pm_get_subflows_max(msk); 642 643 rcu_read_lock(); 644 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 645 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_FULLMESH)) 646 continue; 647 648 if (entry->addr.family != sk->sk_family) { 649 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 650 if ((entry->addr.family == AF_INET && 651 !ipv6_addr_v4mapped(&sk->sk_v6_daddr)) || 652 (sk->sk_family == AF_INET && 653 !ipv6_addr_v4mapped(&entry->addr.addr6))) 654 #endif 655 continue; 656 } 657 658 if (msk->pm.subflows < subflows_max) { 659 msk->pm.subflows++; 660 addrs[i++] = entry->addr; 661 } 662 } 663 rcu_read_unlock(); 664 665 /* If the array is empty, fill in the single 666 * 'IPADDRANY' local address 667 */ 668 if (!i) { 669 memset(&local, 0, sizeof(local)); 670 local.family = msk->pm.remote.family; 671 672 msk->pm.subflows++; 673 addrs[i++] = local; 674 } 675 676 return i; 677 } 678 679 static void mptcp_pm_nl_add_addr_received(struct mptcp_sock *msk) 680 { 681 struct mptcp_addr_info addrs[MPTCP_PM_ADDR_MAX]; 682 struct sock *sk = (struct sock *)msk; 683 unsigned int add_addr_accept_max; 684 struct mptcp_addr_info remote; 685 unsigned int subflows_max; 686 int i, nr; 687 688 add_addr_accept_max = mptcp_pm_get_add_addr_accept_max(msk); 689 subflows_max = mptcp_pm_get_subflows_max(msk); 690 691 pr_debug("accepted %d:%d remote family %d", 692 msk->pm.add_addr_accepted, add_addr_accept_max, 693 msk->pm.remote.family); 694 695 remote = msk->pm.remote; 696 mptcp_pm_announce_addr(msk, &remote, true); 697 mptcp_pm_nl_addr_send_ack(msk); 698 699 if (lookup_subflow_by_daddr(&msk->conn_list, &remote)) 700 return; 701 702 /* pick id 0 port, if none is provided the remote address */ 703 if (!remote.port) 704 remote.port = sk->sk_dport; 705 706 /* connect to the specified remote address, using whatever 707 * local address the routing configuration will pick. 708 */ 709 nr = fill_local_addresses_vec(msk, addrs); 710 711 msk->pm.add_addr_accepted++; 712 if (msk->pm.add_addr_accepted >= add_addr_accept_max || 713 msk->pm.subflows >= subflows_max) 714 WRITE_ONCE(msk->pm.accept_addr, false); 715 716 spin_unlock_bh(&msk->pm.lock); 717 for (i = 0; i < nr; i++) 718 __mptcp_subflow_connect(sk, &addrs[i], &remote); 719 spin_lock_bh(&msk->pm.lock); 720 } 721 722 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk) 723 { 724 struct mptcp_subflow_context *subflow; 725 726 msk_owned_by_me(msk); 727 lockdep_assert_held(&msk->pm.lock); 728 729 if (!mptcp_pm_should_add_signal(msk) && 730 !mptcp_pm_should_rm_signal(msk)) 731 return; 732 733 subflow = list_first_entry_or_null(&msk->conn_list, typeof(*subflow), node); 734 if (subflow) 735 mptcp_pm_send_ack(msk, subflow, false, false); 736 } 737 738 int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk, 739 struct mptcp_addr_info *addr, 740 struct mptcp_addr_info *rem, 741 u8 bkup) 742 { 743 struct mptcp_subflow_context *subflow; 744 745 pr_debug("bkup=%d", bkup); 746 747 mptcp_for_each_subflow(msk, subflow) { 748 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 749 struct mptcp_addr_info local, remote; 750 751 local_address((struct sock_common *)ssk, &local); 752 if (!mptcp_addresses_equal(&local, addr, addr->port)) 753 continue; 754 755 if (rem && rem->family != AF_UNSPEC) { 756 remote_address((struct sock_common *)ssk, &remote); 757 if (!mptcp_addresses_equal(&remote, rem, rem->port)) 758 continue; 759 } 760 761 __mptcp_pm_send_ack(msk, subflow, true, bkup); 762 return 0; 763 } 764 765 return -EINVAL; 766 } 767 768 static bool mptcp_local_id_match(const struct mptcp_sock *msk, u8 local_id, u8 id) 769 { 770 return local_id == id || (!local_id && msk->mpc_endpoint_id == id); 771 } 772 773 static void mptcp_pm_nl_rm_addr_or_subflow(struct mptcp_sock *msk, 774 const struct mptcp_rm_list *rm_list, 775 enum linux_mptcp_mib_field rm_type) 776 { 777 struct mptcp_subflow_context *subflow, *tmp; 778 struct sock *sk = (struct sock *)msk; 779 u8 i; 780 781 pr_debug("%s rm_list_nr %d", 782 rm_type == MPTCP_MIB_RMADDR ? "address" : "subflow", rm_list->nr); 783 784 msk_owned_by_me(msk); 785 786 if (sk->sk_state == TCP_LISTEN) 787 return; 788 789 if (!rm_list->nr) 790 return; 791 792 if (list_empty(&msk->conn_list)) 793 return; 794 795 for (i = 0; i < rm_list->nr; i++) { 796 u8 rm_id = rm_list->ids[i]; 797 bool removed = false; 798 799 list_for_each_entry_safe(subflow, tmp, &msk->conn_list, node) { 800 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 801 int how = RCV_SHUTDOWN | SEND_SHUTDOWN; 802 u8 id = subflow->local_id; 803 804 if (rm_type == MPTCP_MIB_RMADDR && subflow->remote_id != rm_id) 805 continue; 806 if (rm_type == MPTCP_MIB_RMSUBFLOW && !mptcp_local_id_match(msk, id, rm_id)) 807 continue; 808 809 pr_debug(" -> %s rm_list_ids[%d]=%u local_id=%u remote_id=%u mpc_id=%u", 810 rm_type == MPTCP_MIB_RMADDR ? "address" : "subflow", 811 i, rm_id, subflow->local_id, subflow->remote_id, 812 msk->mpc_endpoint_id); 813 spin_unlock_bh(&msk->pm.lock); 814 mptcp_subflow_shutdown(sk, ssk, how); 815 816 /* the following takes care of updating the subflows counter */ 817 mptcp_close_ssk(sk, ssk, subflow); 818 spin_lock_bh(&msk->pm.lock); 819 820 removed = true; 821 __MPTCP_INC_STATS(sock_net(sk), rm_type); 822 } 823 if (rm_type == MPTCP_MIB_RMSUBFLOW) 824 __set_bit(rm_id ? rm_id : msk->mpc_endpoint_id, msk->pm.id_avail_bitmap); 825 if (!removed) 826 continue; 827 828 if (!mptcp_pm_is_kernel(msk)) 829 continue; 830 831 if (rm_type == MPTCP_MIB_RMADDR) { 832 msk->pm.add_addr_accepted--; 833 WRITE_ONCE(msk->pm.accept_addr, true); 834 } else if (rm_type == MPTCP_MIB_RMSUBFLOW) { 835 msk->pm.local_addr_used--; 836 } 837 } 838 } 839 840 static void mptcp_pm_nl_rm_addr_received(struct mptcp_sock *msk) 841 { 842 mptcp_pm_nl_rm_addr_or_subflow(msk, &msk->pm.rm_list_rx, MPTCP_MIB_RMADDR); 843 } 844 845 void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk, 846 const struct mptcp_rm_list *rm_list) 847 { 848 mptcp_pm_nl_rm_addr_or_subflow(msk, rm_list, MPTCP_MIB_RMSUBFLOW); 849 } 850 851 void mptcp_pm_nl_work(struct mptcp_sock *msk) 852 { 853 struct mptcp_pm_data *pm = &msk->pm; 854 855 msk_owned_by_me(msk); 856 857 if (!(pm->status & MPTCP_PM_WORK_MASK)) 858 return; 859 860 spin_lock_bh(&msk->pm.lock); 861 862 pr_debug("msk=%p status=%x", msk, pm->status); 863 if (pm->status & BIT(MPTCP_PM_ADD_ADDR_RECEIVED)) { 864 pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_RECEIVED); 865 mptcp_pm_nl_add_addr_received(msk); 866 } 867 if (pm->status & BIT(MPTCP_PM_ADD_ADDR_SEND_ACK)) { 868 pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_SEND_ACK); 869 mptcp_pm_nl_addr_send_ack(msk); 870 } 871 if (pm->status & BIT(MPTCP_PM_RM_ADDR_RECEIVED)) { 872 pm->status &= ~BIT(MPTCP_PM_RM_ADDR_RECEIVED); 873 mptcp_pm_nl_rm_addr_received(msk); 874 } 875 if (pm->status & BIT(MPTCP_PM_ESTABLISHED)) { 876 pm->status &= ~BIT(MPTCP_PM_ESTABLISHED); 877 mptcp_pm_nl_fully_established(msk); 878 } 879 if (pm->status & BIT(MPTCP_PM_SUBFLOW_ESTABLISHED)) { 880 pm->status &= ~BIT(MPTCP_PM_SUBFLOW_ESTABLISHED); 881 mptcp_pm_nl_subflow_established(msk); 882 } 883 884 spin_unlock_bh(&msk->pm.lock); 885 } 886 887 static bool address_use_port(struct mptcp_pm_addr_entry *entry) 888 { 889 return (entry->flags & 890 (MPTCP_PM_ADDR_FLAG_SIGNAL | MPTCP_PM_ADDR_FLAG_SUBFLOW)) == 891 MPTCP_PM_ADDR_FLAG_SIGNAL; 892 } 893 894 /* caller must ensure the RCU grace period is already elapsed */ 895 static void __mptcp_pm_release_addr_entry(struct mptcp_pm_addr_entry *entry) 896 { 897 if (entry->lsk) 898 sock_release(entry->lsk); 899 kfree(entry); 900 } 901 902 static int mptcp_pm_nl_append_new_local_addr(struct pm_nl_pernet *pernet, 903 struct mptcp_pm_addr_entry *entry) 904 { 905 struct mptcp_pm_addr_entry *cur, *del_entry = NULL; 906 unsigned int addr_max; 907 int ret = -EINVAL; 908 909 spin_lock_bh(&pernet->lock); 910 /* to keep the code simple, don't do IDR-like allocation for address ID, 911 * just bail when we exceed limits 912 */ 913 if (pernet->next_id == MPTCP_PM_MAX_ADDR_ID) 914 pernet->next_id = 1; 915 if (pernet->addrs >= MPTCP_PM_ADDR_MAX) 916 goto out; 917 if (test_bit(entry->addr.id, pernet->id_bitmap)) 918 goto out; 919 920 /* do not insert duplicate address, differentiate on port only 921 * singled addresses 922 */ 923 if (!address_use_port(entry)) 924 entry->addr.port = 0; 925 list_for_each_entry(cur, &pernet->local_addr_list, list) { 926 if (mptcp_addresses_equal(&cur->addr, &entry->addr, 927 cur->addr.port || entry->addr.port)) { 928 /* allow replacing the exiting endpoint only if such 929 * endpoint is an implicit one and the user-space 930 * did not provide an endpoint id 931 */ 932 if (!(cur->flags & MPTCP_PM_ADDR_FLAG_IMPLICIT)) 933 goto out; 934 if (entry->addr.id) 935 goto out; 936 937 pernet->addrs--; 938 entry->addr.id = cur->addr.id; 939 list_del_rcu(&cur->list); 940 del_entry = cur; 941 break; 942 } 943 } 944 945 if (!entry->addr.id) { 946 find_next: 947 entry->addr.id = find_next_zero_bit(pernet->id_bitmap, 948 MPTCP_PM_MAX_ADDR_ID + 1, 949 pernet->next_id); 950 if (!entry->addr.id && pernet->next_id != 1) { 951 pernet->next_id = 1; 952 goto find_next; 953 } 954 } 955 956 if (!entry->addr.id) 957 goto out; 958 959 __set_bit(entry->addr.id, pernet->id_bitmap); 960 if (entry->addr.id > pernet->next_id) 961 pernet->next_id = entry->addr.id; 962 963 if (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL) { 964 addr_max = pernet->add_addr_signal_max; 965 WRITE_ONCE(pernet->add_addr_signal_max, addr_max + 1); 966 } 967 if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) { 968 addr_max = pernet->local_addr_max; 969 WRITE_ONCE(pernet->local_addr_max, addr_max + 1); 970 } 971 972 pernet->addrs++; 973 if (!entry->addr.port) 974 list_add_tail_rcu(&entry->list, &pernet->local_addr_list); 975 else 976 list_add_rcu(&entry->list, &pernet->local_addr_list); 977 ret = entry->addr.id; 978 979 out: 980 spin_unlock_bh(&pernet->lock); 981 982 /* just replaced an existing entry, free it */ 983 if (del_entry) { 984 synchronize_rcu(); 985 __mptcp_pm_release_addr_entry(del_entry); 986 } 987 return ret; 988 } 989 990 static int mptcp_pm_nl_create_listen_socket(struct sock *sk, 991 struct mptcp_pm_addr_entry *entry) 992 { 993 int addrlen = sizeof(struct sockaddr_in); 994 struct sockaddr_storage addr; 995 struct mptcp_sock *msk; 996 struct socket *ssock; 997 int backlog = 1024; 998 int err; 999 1000 err = sock_create_kern(sock_net(sk), entry->addr.family, 1001 SOCK_STREAM, IPPROTO_MPTCP, &entry->lsk); 1002 if (err) 1003 return err; 1004 1005 msk = mptcp_sk(entry->lsk->sk); 1006 if (!msk) { 1007 err = -EINVAL; 1008 goto out; 1009 } 1010 1011 ssock = __mptcp_nmpc_socket(msk); 1012 if (!ssock) { 1013 err = -EINVAL; 1014 goto out; 1015 } 1016 1017 mptcp_info2sockaddr(&entry->addr, &addr, entry->addr.family); 1018 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1019 if (entry->addr.family == AF_INET6) 1020 addrlen = sizeof(struct sockaddr_in6); 1021 #endif 1022 err = kernel_bind(ssock, (struct sockaddr *)&addr, addrlen); 1023 if (err) { 1024 pr_warn("kernel_bind error, err=%d", err); 1025 goto out; 1026 } 1027 1028 err = kernel_listen(ssock, backlog); 1029 if (err) { 1030 pr_warn("kernel_listen error, err=%d", err); 1031 goto out; 1032 } 1033 1034 return 0; 1035 1036 out: 1037 sock_release(entry->lsk); 1038 return err; 1039 } 1040 1041 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct sock_common *skc) 1042 { 1043 struct mptcp_pm_addr_entry *entry; 1044 struct mptcp_addr_info skc_local; 1045 struct mptcp_addr_info msk_local; 1046 struct pm_nl_pernet *pernet; 1047 int ret = -1; 1048 1049 if (WARN_ON_ONCE(!msk)) 1050 return -1; 1051 1052 /* The 0 ID mapping is defined by the first subflow, copied into the msk 1053 * addr 1054 */ 1055 local_address((struct sock_common *)msk, &msk_local); 1056 local_address((struct sock_common *)skc, &skc_local); 1057 if (mptcp_addresses_equal(&msk_local, &skc_local, false)) 1058 return 0; 1059 1060 if (mptcp_pm_is_userspace(msk)) 1061 return mptcp_userspace_pm_get_local_id(msk, &skc_local); 1062 1063 pernet = pm_nl_get_pernet_from_msk(msk); 1064 1065 rcu_read_lock(); 1066 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 1067 if (mptcp_addresses_equal(&entry->addr, &skc_local, entry->addr.port)) { 1068 ret = entry->addr.id; 1069 break; 1070 } 1071 } 1072 rcu_read_unlock(); 1073 if (ret >= 0) 1074 return ret; 1075 1076 /* address not found, add to local list */ 1077 entry = kmalloc(sizeof(*entry), GFP_ATOMIC); 1078 if (!entry) 1079 return -ENOMEM; 1080 1081 entry->addr = skc_local; 1082 entry->addr.id = 0; 1083 entry->addr.port = 0; 1084 entry->ifindex = 0; 1085 entry->flags = MPTCP_PM_ADDR_FLAG_IMPLICIT; 1086 entry->lsk = NULL; 1087 ret = mptcp_pm_nl_append_new_local_addr(pernet, entry); 1088 if (ret < 0) 1089 kfree(entry); 1090 1091 return ret; 1092 } 1093 1094 #define MPTCP_PM_CMD_GRP_OFFSET 0 1095 #define MPTCP_PM_EV_GRP_OFFSET 1 1096 1097 static const struct genl_multicast_group mptcp_pm_mcgrps[] = { 1098 [MPTCP_PM_CMD_GRP_OFFSET] = { .name = MPTCP_PM_CMD_GRP_NAME, }, 1099 [MPTCP_PM_EV_GRP_OFFSET] = { .name = MPTCP_PM_EV_GRP_NAME, 1100 .flags = GENL_UNS_ADMIN_PERM, 1101 }, 1102 }; 1103 1104 static const struct nla_policy 1105 mptcp_pm_addr_policy[MPTCP_PM_ADDR_ATTR_MAX + 1] = { 1106 [MPTCP_PM_ADDR_ATTR_FAMILY] = { .type = NLA_U16, }, 1107 [MPTCP_PM_ADDR_ATTR_ID] = { .type = NLA_U8, }, 1108 [MPTCP_PM_ADDR_ATTR_ADDR4] = { .type = NLA_U32, }, 1109 [MPTCP_PM_ADDR_ATTR_ADDR6] = 1110 NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)), 1111 [MPTCP_PM_ADDR_ATTR_PORT] = { .type = NLA_U16 }, 1112 [MPTCP_PM_ADDR_ATTR_FLAGS] = { .type = NLA_U32 }, 1113 [MPTCP_PM_ADDR_ATTR_IF_IDX] = { .type = NLA_S32 }, 1114 }; 1115 1116 static const struct nla_policy mptcp_pm_policy[MPTCP_PM_ATTR_MAX + 1] = { 1117 [MPTCP_PM_ATTR_ADDR] = 1118 NLA_POLICY_NESTED(mptcp_pm_addr_policy), 1119 [MPTCP_PM_ATTR_RCV_ADD_ADDRS] = { .type = NLA_U32, }, 1120 [MPTCP_PM_ATTR_SUBFLOWS] = { .type = NLA_U32, }, 1121 [MPTCP_PM_ATTR_TOKEN] = { .type = NLA_U32, }, 1122 [MPTCP_PM_ATTR_LOC_ID] = { .type = NLA_U8, }, 1123 [MPTCP_PM_ATTR_ADDR_REMOTE] = 1124 NLA_POLICY_NESTED(mptcp_pm_addr_policy), 1125 }; 1126 1127 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk) 1128 { 1129 struct mptcp_subflow_context *iter, *subflow = mptcp_subflow_ctx(ssk); 1130 struct sock *sk = (struct sock *)msk; 1131 unsigned int active_max_loss_cnt; 1132 struct net *net = sock_net(sk); 1133 unsigned int stale_loss_cnt; 1134 bool slow; 1135 1136 stale_loss_cnt = mptcp_stale_loss_cnt(net); 1137 if (subflow->stale || !stale_loss_cnt || subflow->stale_count <= stale_loss_cnt) 1138 return; 1139 1140 /* look for another available subflow not in loss state */ 1141 active_max_loss_cnt = max_t(int, stale_loss_cnt - 1, 1); 1142 mptcp_for_each_subflow(msk, iter) { 1143 if (iter != subflow && mptcp_subflow_active(iter) && 1144 iter->stale_count < active_max_loss_cnt) { 1145 /* we have some alternatives, try to mark this subflow as idle ...*/ 1146 slow = lock_sock_fast(ssk); 1147 if (!tcp_rtx_and_write_queues_empty(ssk)) { 1148 subflow->stale = 1; 1149 __mptcp_retransmit_pending_data(sk); 1150 MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_SUBFLOWSTALE); 1151 } 1152 unlock_sock_fast(ssk, slow); 1153 1154 /* always try to push the pending data regardless of re-injections: 1155 * we can possibly use backup subflows now, and subflow selection 1156 * is cheap under the msk socket lock 1157 */ 1158 __mptcp_push_pending(sk, 0); 1159 return; 1160 } 1161 } 1162 } 1163 1164 static int mptcp_pm_family_to_addr(int family) 1165 { 1166 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1167 if (family == AF_INET6) 1168 return MPTCP_PM_ADDR_ATTR_ADDR6; 1169 #endif 1170 return MPTCP_PM_ADDR_ATTR_ADDR4; 1171 } 1172 1173 static int mptcp_pm_parse_pm_addr_attr(struct nlattr *tb[], 1174 const struct nlattr *attr, 1175 struct genl_info *info, 1176 struct mptcp_addr_info *addr, 1177 bool require_family) 1178 { 1179 int err, addr_addr; 1180 1181 if (!attr) { 1182 GENL_SET_ERR_MSG(info, "missing address info"); 1183 return -EINVAL; 1184 } 1185 1186 /* no validation needed - was already done via nested policy */ 1187 err = nla_parse_nested_deprecated(tb, MPTCP_PM_ADDR_ATTR_MAX, attr, 1188 mptcp_pm_addr_policy, info->extack); 1189 if (err) 1190 return err; 1191 1192 if (tb[MPTCP_PM_ADDR_ATTR_ID]) 1193 addr->id = nla_get_u8(tb[MPTCP_PM_ADDR_ATTR_ID]); 1194 1195 if (!tb[MPTCP_PM_ADDR_ATTR_FAMILY]) { 1196 if (!require_family) 1197 return err; 1198 1199 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1200 "missing family"); 1201 return -EINVAL; 1202 } 1203 1204 addr->family = nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_FAMILY]); 1205 if (addr->family != AF_INET 1206 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1207 && addr->family != AF_INET6 1208 #endif 1209 ) { 1210 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1211 "unknown address family"); 1212 return -EINVAL; 1213 } 1214 addr_addr = mptcp_pm_family_to_addr(addr->family); 1215 if (!tb[addr_addr]) { 1216 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1217 "missing address data"); 1218 return -EINVAL; 1219 } 1220 1221 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1222 if (addr->family == AF_INET6) 1223 addr->addr6 = nla_get_in6_addr(tb[addr_addr]); 1224 else 1225 #endif 1226 addr->addr.s_addr = nla_get_in_addr(tb[addr_addr]); 1227 1228 if (tb[MPTCP_PM_ADDR_ATTR_PORT]) 1229 addr->port = htons(nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_PORT])); 1230 1231 return err; 1232 } 1233 1234 int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info, 1235 struct mptcp_addr_info *addr) 1236 { 1237 struct nlattr *tb[MPTCP_PM_ADDR_ATTR_MAX + 1]; 1238 1239 memset(addr, 0, sizeof(*addr)); 1240 1241 return mptcp_pm_parse_pm_addr_attr(tb, attr, info, addr, true); 1242 } 1243 1244 int mptcp_pm_parse_entry(struct nlattr *attr, struct genl_info *info, 1245 bool require_family, 1246 struct mptcp_pm_addr_entry *entry) 1247 { 1248 struct nlattr *tb[MPTCP_PM_ADDR_ATTR_MAX + 1]; 1249 int err; 1250 1251 memset(entry, 0, sizeof(*entry)); 1252 1253 err = mptcp_pm_parse_pm_addr_attr(tb, attr, info, &entry->addr, require_family); 1254 if (err) 1255 return err; 1256 1257 if (tb[MPTCP_PM_ADDR_ATTR_IF_IDX]) { 1258 u32 val = nla_get_s32(tb[MPTCP_PM_ADDR_ATTR_IF_IDX]); 1259 1260 entry->ifindex = val; 1261 } 1262 1263 if (tb[MPTCP_PM_ADDR_ATTR_FLAGS]) 1264 entry->flags = nla_get_u32(tb[MPTCP_PM_ADDR_ATTR_FLAGS]); 1265 1266 if (tb[MPTCP_PM_ADDR_ATTR_PORT]) 1267 entry->addr.port = htons(nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_PORT])); 1268 1269 return 0; 1270 } 1271 1272 static struct pm_nl_pernet *genl_info_pm_nl(struct genl_info *info) 1273 { 1274 return pm_nl_get_pernet(genl_info_net(info)); 1275 } 1276 1277 static int mptcp_nl_add_subflow_or_signal_addr(struct net *net) 1278 { 1279 struct mptcp_sock *msk; 1280 long s_slot = 0, s_num = 0; 1281 1282 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1283 struct sock *sk = (struct sock *)msk; 1284 1285 if (!READ_ONCE(msk->fully_established) || 1286 mptcp_pm_is_userspace(msk)) 1287 goto next; 1288 1289 lock_sock(sk); 1290 spin_lock_bh(&msk->pm.lock); 1291 mptcp_pm_create_subflow_or_signal_addr(msk); 1292 spin_unlock_bh(&msk->pm.lock); 1293 release_sock(sk); 1294 1295 next: 1296 sock_put(sk); 1297 cond_resched(); 1298 } 1299 1300 return 0; 1301 } 1302 1303 static int mptcp_nl_cmd_add_addr(struct sk_buff *skb, struct genl_info *info) 1304 { 1305 struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR]; 1306 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1307 struct mptcp_pm_addr_entry addr, *entry; 1308 int ret; 1309 1310 ret = mptcp_pm_parse_entry(attr, info, true, &addr); 1311 if (ret < 0) 1312 return ret; 1313 1314 if (addr.addr.port && !(addr.flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) { 1315 GENL_SET_ERR_MSG(info, "flags must have signal when using port"); 1316 return -EINVAL; 1317 } 1318 1319 if (addr.flags & MPTCP_PM_ADDR_FLAG_SIGNAL && 1320 addr.flags & MPTCP_PM_ADDR_FLAG_FULLMESH) { 1321 GENL_SET_ERR_MSG(info, "flags mustn't have both signal and fullmesh"); 1322 return -EINVAL; 1323 } 1324 1325 if (addr.flags & MPTCP_PM_ADDR_FLAG_IMPLICIT) { 1326 GENL_SET_ERR_MSG(info, "can't create IMPLICIT endpoint"); 1327 return -EINVAL; 1328 } 1329 1330 entry = kmalloc(sizeof(*entry), GFP_KERNEL); 1331 if (!entry) { 1332 GENL_SET_ERR_MSG(info, "can't allocate addr"); 1333 return -ENOMEM; 1334 } 1335 1336 *entry = addr; 1337 if (entry->addr.port) { 1338 ret = mptcp_pm_nl_create_listen_socket(skb->sk, entry); 1339 if (ret) { 1340 GENL_SET_ERR_MSG(info, "create listen socket error"); 1341 kfree(entry); 1342 return ret; 1343 } 1344 } 1345 ret = mptcp_pm_nl_append_new_local_addr(pernet, entry); 1346 if (ret < 0) { 1347 GENL_SET_ERR_MSG(info, "too many addresses or duplicate one"); 1348 if (entry->lsk) 1349 sock_release(entry->lsk); 1350 kfree(entry); 1351 return ret; 1352 } 1353 1354 mptcp_nl_add_subflow_or_signal_addr(sock_net(skb->sk)); 1355 1356 return 0; 1357 } 1358 1359 int mptcp_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, unsigned int id, 1360 u8 *flags, int *ifindex) 1361 { 1362 struct mptcp_pm_addr_entry *entry; 1363 struct sock *sk = (struct sock *)msk; 1364 struct net *net = sock_net(sk); 1365 1366 *flags = 0; 1367 *ifindex = 0; 1368 1369 if (id) { 1370 if (mptcp_pm_is_userspace(msk)) 1371 return mptcp_userspace_pm_get_flags_and_ifindex_by_id(msk, 1372 id, 1373 flags, 1374 ifindex); 1375 1376 rcu_read_lock(); 1377 entry = __lookup_addr_by_id(pm_nl_get_pernet(net), id); 1378 if (entry) { 1379 *flags = entry->flags; 1380 *ifindex = entry->ifindex; 1381 } 1382 rcu_read_unlock(); 1383 } 1384 1385 return 0; 1386 } 1387 1388 static bool remove_anno_list_by_saddr(struct mptcp_sock *msk, 1389 const struct mptcp_addr_info *addr) 1390 { 1391 struct mptcp_pm_add_entry *entry; 1392 1393 entry = mptcp_pm_del_add_timer(msk, addr, false); 1394 if (entry) { 1395 list_del(&entry->list); 1396 kfree(entry); 1397 return true; 1398 } 1399 1400 return false; 1401 } 1402 1403 static bool mptcp_pm_remove_anno_addr(struct mptcp_sock *msk, 1404 const struct mptcp_addr_info *addr, 1405 bool force) 1406 { 1407 struct mptcp_rm_list list = { .nr = 0 }; 1408 bool ret; 1409 1410 list.ids[list.nr++] = addr->id; 1411 1412 ret = remove_anno_list_by_saddr(msk, addr); 1413 if (ret || force) { 1414 spin_lock_bh(&msk->pm.lock); 1415 mptcp_pm_remove_addr(msk, &list); 1416 spin_unlock_bh(&msk->pm.lock); 1417 } 1418 return ret; 1419 } 1420 1421 static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net, 1422 const struct mptcp_pm_addr_entry *entry) 1423 { 1424 const struct mptcp_addr_info *addr = &entry->addr; 1425 struct mptcp_rm_list list = { .nr = 0 }; 1426 long s_slot = 0, s_num = 0; 1427 struct mptcp_sock *msk; 1428 1429 pr_debug("remove_id=%d", addr->id); 1430 1431 list.ids[list.nr++] = addr->id; 1432 1433 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1434 struct sock *sk = (struct sock *)msk; 1435 bool remove_subflow; 1436 1437 if (mptcp_pm_is_userspace(msk)) 1438 goto next; 1439 1440 if (list_empty(&msk->conn_list)) { 1441 mptcp_pm_remove_anno_addr(msk, addr, false); 1442 goto next; 1443 } 1444 1445 lock_sock(sk); 1446 remove_subflow = lookup_subflow_by_saddr(&msk->conn_list, addr); 1447 mptcp_pm_remove_anno_addr(msk, addr, remove_subflow && 1448 !(entry->flags & MPTCP_PM_ADDR_FLAG_IMPLICIT)); 1449 if (remove_subflow) 1450 mptcp_pm_remove_subflow(msk, &list); 1451 release_sock(sk); 1452 1453 next: 1454 sock_put(sk); 1455 cond_resched(); 1456 } 1457 1458 return 0; 1459 } 1460 1461 static int mptcp_nl_remove_id_zero_address(struct net *net, 1462 struct mptcp_addr_info *addr) 1463 { 1464 struct mptcp_rm_list list = { .nr = 0 }; 1465 long s_slot = 0, s_num = 0; 1466 struct mptcp_sock *msk; 1467 1468 list.ids[list.nr++] = 0; 1469 1470 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1471 struct sock *sk = (struct sock *)msk; 1472 struct mptcp_addr_info msk_local; 1473 1474 if (list_empty(&msk->conn_list) || mptcp_pm_is_userspace(msk)) 1475 goto next; 1476 1477 local_address((struct sock_common *)msk, &msk_local); 1478 if (!mptcp_addresses_equal(&msk_local, addr, addr->port)) 1479 goto next; 1480 1481 lock_sock(sk); 1482 spin_lock_bh(&msk->pm.lock); 1483 mptcp_pm_remove_addr(msk, &list); 1484 mptcp_pm_nl_rm_subflow_received(msk, &list); 1485 spin_unlock_bh(&msk->pm.lock); 1486 release_sock(sk); 1487 1488 next: 1489 sock_put(sk); 1490 cond_resched(); 1491 } 1492 1493 return 0; 1494 } 1495 1496 static int mptcp_nl_cmd_del_addr(struct sk_buff *skb, struct genl_info *info) 1497 { 1498 struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR]; 1499 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1500 struct mptcp_pm_addr_entry addr, *entry; 1501 unsigned int addr_max; 1502 int ret; 1503 1504 ret = mptcp_pm_parse_entry(attr, info, false, &addr); 1505 if (ret < 0) 1506 return ret; 1507 1508 /* the zero id address is special: the first address used by the msk 1509 * always gets such an id, so different subflows can have different zero 1510 * id addresses. Additionally zero id is not accounted for in id_bitmap. 1511 * Let's use an 'mptcp_rm_list' instead of the common remove code. 1512 */ 1513 if (addr.addr.id == 0) 1514 return mptcp_nl_remove_id_zero_address(sock_net(skb->sk), &addr.addr); 1515 1516 spin_lock_bh(&pernet->lock); 1517 entry = __lookup_addr_by_id(pernet, addr.addr.id); 1518 if (!entry) { 1519 GENL_SET_ERR_MSG(info, "address not found"); 1520 spin_unlock_bh(&pernet->lock); 1521 return -EINVAL; 1522 } 1523 if (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL) { 1524 addr_max = pernet->add_addr_signal_max; 1525 WRITE_ONCE(pernet->add_addr_signal_max, addr_max - 1); 1526 } 1527 if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) { 1528 addr_max = pernet->local_addr_max; 1529 WRITE_ONCE(pernet->local_addr_max, addr_max - 1); 1530 } 1531 1532 pernet->addrs--; 1533 list_del_rcu(&entry->list); 1534 __clear_bit(entry->addr.id, pernet->id_bitmap); 1535 spin_unlock_bh(&pernet->lock); 1536 1537 mptcp_nl_remove_subflow_and_signal_addr(sock_net(skb->sk), entry); 1538 synchronize_rcu(); 1539 __mptcp_pm_release_addr_entry(entry); 1540 1541 return ret; 1542 } 1543 1544 void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk, 1545 struct list_head *rm_list) 1546 { 1547 struct mptcp_rm_list alist = { .nr = 0 }, slist = { .nr = 0 }; 1548 struct mptcp_pm_addr_entry *entry; 1549 1550 list_for_each_entry(entry, rm_list, list) { 1551 if (lookup_subflow_by_saddr(&msk->conn_list, &entry->addr) && 1552 slist.nr < MPTCP_RM_IDS_MAX) 1553 slist.ids[slist.nr++] = entry->addr.id; 1554 1555 if (remove_anno_list_by_saddr(msk, &entry->addr) && 1556 alist.nr < MPTCP_RM_IDS_MAX) 1557 alist.ids[alist.nr++] = entry->addr.id; 1558 } 1559 1560 if (alist.nr) { 1561 spin_lock_bh(&msk->pm.lock); 1562 mptcp_pm_remove_addr(msk, &alist); 1563 spin_unlock_bh(&msk->pm.lock); 1564 } 1565 if (slist.nr) 1566 mptcp_pm_remove_subflow(msk, &slist); 1567 } 1568 1569 static void mptcp_nl_remove_addrs_list(struct net *net, 1570 struct list_head *rm_list) 1571 { 1572 long s_slot = 0, s_num = 0; 1573 struct mptcp_sock *msk; 1574 1575 if (list_empty(rm_list)) 1576 return; 1577 1578 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1579 struct sock *sk = (struct sock *)msk; 1580 1581 if (!mptcp_pm_is_userspace(msk)) { 1582 lock_sock(sk); 1583 mptcp_pm_remove_addrs_and_subflows(msk, rm_list); 1584 release_sock(sk); 1585 } 1586 1587 sock_put(sk); 1588 cond_resched(); 1589 } 1590 } 1591 1592 /* caller must ensure the RCU grace period is already elapsed */ 1593 static void __flush_addrs(struct list_head *list) 1594 { 1595 while (!list_empty(list)) { 1596 struct mptcp_pm_addr_entry *cur; 1597 1598 cur = list_entry(list->next, 1599 struct mptcp_pm_addr_entry, list); 1600 list_del_rcu(&cur->list); 1601 __mptcp_pm_release_addr_entry(cur); 1602 } 1603 } 1604 1605 static void __reset_counters(struct pm_nl_pernet *pernet) 1606 { 1607 WRITE_ONCE(pernet->add_addr_signal_max, 0); 1608 WRITE_ONCE(pernet->add_addr_accept_max, 0); 1609 WRITE_ONCE(pernet->local_addr_max, 0); 1610 pernet->addrs = 0; 1611 } 1612 1613 static int mptcp_nl_cmd_flush_addrs(struct sk_buff *skb, struct genl_info *info) 1614 { 1615 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1616 LIST_HEAD(free_list); 1617 1618 spin_lock_bh(&pernet->lock); 1619 list_splice_init(&pernet->local_addr_list, &free_list); 1620 __reset_counters(pernet); 1621 pernet->next_id = 1; 1622 bitmap_zero(pernet->id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); 1623 spin_unlock_bh(&pernet->lock); 1624 mptcp_nl_remove_addrs_list(sock_net(skb->sk), &free_list); 1625 synchronize_rcu(); 1626 __flush_addrs(&free_list); 1627 return 0; 1628 } 1629 1630 static int mptcp_nl_fill_addr(struct sk_buff *skb, 1631 struct mptcp_pm_addr_entry *entry) 1632 { 1633 struct mptcp_addr_info *addr = &entry->addr; 1634 struct nlattr *attr; 1635 1636 attr = nla_nest_start(skb, MPTCP_PM_ATTR_ADDR); 1637 if (!attr) 1638 return -EMSGSIZE; 1639 1640 if (nla_put_u16(skb, MPTCP_PM_ADDR_ATTR_FAMILY, addr->family)) 1641 goto nla_put_failure; 1642 if (nla_put_u16(skb, MPTCP_PM_ADDR_ATTR_PORT, ntohs(addr->port))) 1643 goto nla_put_failure; 1644 if (nla_put_u8(skb, MPTCP_PM_ADDR_ATTR_ID, addr->id)) 1645 goto nla_put_failure; 1646 if (nla_put_u32(skb, MPTCP_PM_ADDR_ATTR_FLAGS, entry->flags)) 1647 goto nla_put_failure; 1648 if (entry->ifindex && 1649 nla_put_s32(skb, MPTCP_PM_ADDR_ATTR_IF_IDX, entry->ifindex)) 1650 goto nla_put_failure; 1651 1652 if (addr->family == AF_INET && 1653 nla_put_in_addr(skb, MPTCP_PM_ADDR_ATTR_ADDR4, 1654 addr->addr.s_addr)) 1655 goto nla_put_failure; 1656 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1657 else if (addr->family == AF_INET6 && 1658 nla_put_in6_addr(skb, MPTCP_PM_ADDR_ATTR_ADDR6, &addr->addr6)) 1659 goto nla_put_failure; 1660 #endif 1661 nla_nest_end(skb, attr); 1662 return 0; 1663 1664 nla_put_failure: 1665 nla_nest_cancel(skb, attr); 1666 return -EMSGSIZE; 1667 } 1668 1669 static int mptcp_nl_cmd_get_addr(struct sk_buff *skb, struct genl_info *info) 1670 { 1671 struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR]; 1672 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1673 struct mptcp_pm_addr_entry addr, *entry; 1674 struct sk_buff *msg; 1675 void *reply; 1676 int ret; 1677 1678 ret = mptcp_pm_parse_entry(attr, info, false, &addr); 1679 if (ret < 0) 1680 return ret; 1681 1682 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 1683 if (!msg) 1684 return -ENOMEM; 1685 1686 reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0, 1687 info->genlhdr->cmd); 1688 if (!reply) { 1689 GENL_SET_ERR_MSG(info, "not enough space in Netlink message"); 1690 ret = -EMSGSIZE; 1691 goto fail; 1692 } 1693 1694 spin_lock_bh(&pernet->lock); 1695 entry = __lookup_addr_by_id(pernet, addr.addr.id); 1696 if (!entry) { 1697 GENL_SET_ERR_MSG(info, "address not found"); 1698 ret = -EINVAL; 1699 goto unlock_fail; 1700 } 1701 1702 ret = mptcp_nl_fill_addr(msg, entry); 1703 if (ret) 1704 goto unlock_fail; 1705 1706 genlmsg_end(msg, reply); 1707 ret = genlmsg_reply(msg, info); 1708 spin_unlock_bh(&pernet->lock); 1709 return ret; 1710 1711 unlock_fail: 1712 spin_unlock_bh(&pernet->lock); 1713 1714 fail: 1715 nlmsg_free(msg); 1716 return ret; 1717 } 1718 1719 static int mptcp_nl_cmd_dump_addrs(struct sk_buff *msg, 1720 struct netlink_callback *cb) 1721 { 1722 struct net *net = sock_net(msg->sk); 1723 struct mptcp_pm_addr_entry *entry; 1724 struct pm_nl_pernet *pernet; 1725 int id = cb->args[0]; 1726 void *hdr; 1727 int i; 1728 1729 pernet = pm_nl_get_pernet(net); 1730 1731 spin_lock_bh(&pernet->lock); 1732 for (i = id; i < MPTCP_PM_MAX_ADDR_ID + 1; i++) { 1733 if (test_bit(i, pernet->id_bitmap)) { 1734 entry = __lookup_addr_by_id(pernet, i); 1735 if (!entry) 1736 break; 1737 1738 if (entry->addr.id <= id) 1739 continue; 1740 1741 hdr = genlmsg_put(msg, NETLINK_CB(cb->skb).portid, 1742 cb->nlh->nlmsg_seq, &mptcp_genl_family, 1743 NLM_F_MULTI, MPTCP_PM_CMD_GET_ADDR); 1744 if (!hdr) 1745 break; 1746 1747 if (mptcp_nl_fill_addr(msg, entry) < 0) { 1748 genlmsg_cancel(msg, hdr); 1749 break; 1750 } 1751 1752 id = entry->addr.id; 1753 genlmsg_end(msg, hdr); 1754 } 1755 } 1756 spin_unlock_bh(&pernet->lock); 1757 1758 cb->args[0] = id; 1759 return msg->len; 1760 } 1761 1762 static int parse_limit(struct genl_info *info, int id, unsigned int *limit) 1763 { 1764 struct nlattr *attr = info->attrs[id]; 1765 1766 if (!attr) 1767 return 0; 1768 1769 *limit = nla_get_u32(attr); 1770 if (*limit > MPTCP_PM_ADDR_MAX) { 1771 GENL_SET_ERR_MSG(info, "limit greater than maximum"); 1772 return -EINVAL; 1773 } 1774 return 0; 1775 } 1776 1777 static int 1778 mptcp_nl_cmd_set_limits(struct sk_buff *skb, struct genl_info *info) 1779 { 1780 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1781 unsigned int rcv_addrs, subflows; 1782 int ret; 1783 1784 spin_lock_bh(&pernet->lock); 1785 rcv_addrs = pernet->add_addr_accept_max; 1786 ret = parse_limit(info, MPTCP_PM_ATTR_RCV_ADD_ADDRS, &rcv_addrs); 1787 if (ret) 1788 goto unlock; 1789 1790 subflows = pernet->subflows_max; 1791 ret = parse_limit(info, MPTCP_PM_ATTR_SUBFLOWS, &subflows); 1792 if (ret) 1793 goto unlock; 1794 1795 WRITE_ONCE(pernet->add_addr_accept_max, rcv_addrs); 1796 WRITE_ONCE(pernet->subflows_max, subflows); 1797 1798 unlock: 1799 spin_unlock_bh(&pernet->lock); 1800 return ret; 1801 } 1802 1803 static int 1804 mptcp_nl_cmd_get_limits(struct sk_buff *skb, struct genl_info *info) 1805 { 1806 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1807 struct sk_buff *msg; 1808 void *reply; 1809 1810 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 1811 if (!msg) 1812 return -ENOMEM; 1813 1814 reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0, 1815 MPTCP_PM_CMD_GET_LIMITS); 1816 if (!reply) 1817 goto fail; 1818 1819 if (nla_put_u32(msg, MPTCP_PM_ATTR_RCV_ADD_ADDRS, 1820 READ_ONCE(pernet->add_addr_accept_max))) 1821 goto fail; 1822 1823 if (nla_put_u32(msg, MPTCP_PM_ATTR_SUBFLOWS, 1824 READ_ONCE(pernet->subflows_max))) 1825 goto fail; 1826 1827 genlmsg_end(msg, reply); 1828 return genlmsg_reply(msg, info); 1829 1830 fail: 1831 GENL_SET_ERR_MSG(info, "not enough space in Netlink message"); 1832 nlmsg_free(msg); 1833 return -EMSGSIZE; 1834 } 1835 1836 static void mptcp_pm_nl_fullmesh(struct mptcp_sock *msk, 1837 struct mptcp_addr_info *addr) 1838 { 1839 struct mptcp_rm_list list = { .nr = 0 }; 1840 1841 list.ids[list.nr++] = addr->id; 1842 1843 spin_lock_bh(&msk->pm.lock); 1844 mptcp_pm_nl_rm_subflow_received(msk, &list); 1845 mptcp_pm_create_subflow_or_signal_addr(msk); 1846 spin_unlock_bh(&msk->pm.lock); 1847 } 1848 1849 static int mptcp_nl_set_flags(struct net *net, 1850 struct mptcp_addr_info *addr, 1851 u8 bkup, u8 changed) 1852 { 1853 long s_slot = 0, s_num = 0; 1854 struct mptcp_sock *msk; 1855 int ret = -EINVAL; 1856 1857 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1858 struct sock *sk = (struct sock *)msk; 1859 1860 if (list_empty(&msk->conn_list) || mptcp_pm_is_userspace(msk)) 1861 goto next; 1862 1863 lock_sock(sk); 1864 if (changed & MPTCP_PM_ADDR_FLAG_BACKUP) 1865 ret = mptcp_pm_nl_mp_prio_send_ack(msk, addr, NULL, bkup); 1866 if (changed & MPTCP_PM_ADDR_FLAG_FULLMESH) 1867 mptcp_pm_nl_fullmesh(msk, addr); 1868 release_sock(sk); 1869 1870 next: 1871 sock_put(sk); 1872 cond_resched(); 1873 } 1874 1875 return ret; 1876 } 1877 1878 static int mptcp_nl_cmd_set_flags(struct sk_buff *skb, struct genl_info *info) 1879 { 1880 struct mptcp_pm_addr_entry addr = { .addr = { .family = AF_UNSPEC }, }, *entry; 1881 struct mptcp_pm_addr_entry remote = { .addr = { .family = AF_UNSPEC }, }; 1882 struct nlattr *attr_rem = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE]; 1883 struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN]; 1884 struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR]; 1885 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1886 u8 changed, mask = MPTCP_PM_ADDR_FLAG_BACKUP | 1887 MPTCP_PM_ADDR_FLAG_FULLMESH; 1888 struct net *net = sock_net(skb->sk); 1889 u8 bkup = 0, lookup_by_id = 0; 1890 int ret; 1891 1892 ret = mptcp_pm_parse_entry(attr, info, false, &addr); 1893 if (ret < 0) 1894 return ret; 1895 1896 if (attr_rem) { 1897 ret = mptcp_pm_parse_entry(attr_rem, info, false, &remote); 1898 if (ret < 0) 1899 return ret; 1900 } 1901 1902 if (addr.flags & MPTCP_PM_ADDR_FLAG_BACKUP) 1903 bkup = 1; 1904 if (addr.addr.family == AF_UNSPEC) { 1905 lookup_by_id = 1; 1906 if (!addr.addr.id) 1907 return -EOPNOTSUPP; 1908 } 1909 1910 if (token) 1911 return mptcp_userspace_pm_set_flags(sock_net(skb->sk), 1912 token, &addr, &remote, bkup); 1913 1914 spin_lock_bh(&pernet->lock); 1915 entry = __lookup_addr(pernet, &addr.addr, lookup_by_id); 1916 if (!entry) { 1917 spin_unlock_bh(&pernet->lock); 1918 return -EINVAL; 1919 } 1920 if ((addr.flags & MPTCP_PM_ADDR_FLAG_FULLMESH) && 1921 (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) { 1922 spin_unlock_bh(&pernet->lock); 1923 return -EINVAL; 1924 } 1925 1926 changed = (addr.flags ^ entry->flags) & mask; 1927 entry->flags = (entry->flags & ~mask) | (addr.flags & mask); 1928 addr = *entry; 1929 spin_unlock_bh(&pernet->lock); 1930 1931 mptcp_nl_set_flags(net, &addr.addr, bkup, changed); 1932 return 0; 1933 } 1934 1935 static void mptcp_nl_mcast_send(struct net *net, struct sk_buff *nlskb, gfp_t gfp) 1936 { 1937 genlmsg_multicast_netns(&mptcp_genl_family, net, 1938 nlskb, 0, MPTCP_PM_EV_GRP_OFFSET, gfp); 1939 } 1940 1941 bool mptcp_userspace_pm_active(const struct mptcp_sock *msk) 1942 { 1943 return genl_has_listeners(&mptcp_genl_family, 1944 sock_net((const struct sock *)msk), 1945 MPTCP_PM_EV_GRP_OFFSET); 1946 } 1947 1948 static int mptcp_event_add_subflow(struct sk_buff *skb, const struct sock *ssk) 1949 { 1950 const struct inet_sock *issk = inet_sk(ssk); 1951 const struct mptcp_subflow_context *sf; 1952 1953 if (nla_put_u16(skb, MPTCP_ATTR_FAMILY, ssk->sk_family)) 1954 return -EMSGSIZE; 1955 1956 switch (ssk->sk_family) { 1957 case AF_INET: 1958 if (nla_put_in_addr(skb, MPTCP_ATTR_SADDR4, issk->inet_saddr)) 1959 return -EMSGSIZE; 1960 if (nla_put_in_addr(skb, MPTCP_ATTR_DADDR4, issk->inet_daddr)) 1961 return -EMSGSIZE; 1962 break; 1963 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1964 case AF_INET6: { 1965 const struct ipv6_pinfo *np = inet6_sk(ssk); 1966 1967 if (nla_put_in6_addr(skb, MPTCP_ATTR_SADDR6, &np->saddr)) 1968 return -EMSGSIZE; 1969 if (nla_put_in6_addr(skb, MPTCP_ATTR_DADDR6, &ssk->sk_v6_daddr)) 1970 return -EMSGSIZE; 1971 break; 1972 } 1973 #endif 1974 default: 1975 WARN_ON_ONCE(1); 1976 return -EMSGSIZE; 1977 } 1978 1979 if (nla_put_be16(skb, MPTCP_ATTR_SPORT, issk->inet_sport)) 1980 return -EMSGSIZE; 1981 if (nla_put_be16(skb, MPTCP_ATTR_DPORT, issk->inet_dport)) 1982 return -EMSGSIZE; 1983 1984 sf = mptcp_subflow_ctx(ssk); 1985 if (WARN_ON_ONCE(!sf)) 1986 return -EINVAL; 1987 1988 if (nla_put_u8(skb, MPTCP_ATTR_LOC_ID, sf->local_id)) 1989 return -EMSGSIZE; 1990 1991 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, sf->remote_id)) 1992 return -EMSGSIZE; 1993 1994 return 0; 1995 } 1996 1997 static int mptcp_event_put_token_and_ssk(struct sk_buff *skb, 1998 const struct mptcp_sock *msk, 1999 const struct sock *ssk) 2000 { 2001 const struct sock *sk = (const struct sock *)msk; 2002 const struct mptcp_subflow_context *sf; 2003 u8 sk_err; 2004 2005 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token)) 2006 return -EMSGSIZE; 2007 2008 if (mptcp_event_add_subflow(skb, ssk)) 2009 return -EMSGSIZE; 2010 2011 sf = mptcp_subflow_ctx(ssk); 2012 if (WARN_ON_ONCE(!sf)) 2013 return -EINVAL; 2014 2015 if (nla_put_u8(skb, MPTCP_ATTR_BACKUP, sf->backup)) 2016 return -EMSGSIZE; 2017 2018 if (ssk->sk_bound_dev_if && 2019 nla_put_s32(skb, MPTCP_ATTR_IF_IDX, ssk->sk_bound_dev_if)) 2020 return -EMSGSIZE; 2021 2022 sk_err = ssk->sk_err; 2023 if (sk_err && sk->sk_state == TCP_ESTABLISHED && 2024 nla_put_u8(skb, MPTCP_ATTR_ERROR, sk_err)) 2025 return -EMSGSIZE; 2026 2027 return 0; 2028 } 2029 2030 static int mptcp_event_sub_established(struct sk_buff *skb, 2031 const struct mptcp_sock *msk, 2032 const struct sock *ssk) 2033 { 2034 return mptcp_event_put_token_and_ssk(skb, msk, ssk); 2035 } 2036 2037 static int mptcp_event_sub_closed(struct sk_buff *skb, 2038 const struct mptcp_sock *msk, 2039 const struct sock *ssk) 2040 { 2041 const struct mptcp_subflow_context *sf; 2042 2043 if (mptcp_event_put_token_and_ssk(skb, msk, ssk)) 2044 return -EMSGSIZE; 2045 2046 sf = mptcp_subflow_ctx(ssk); 2047 if (!sf->reset_seen) 2048 return 0; 2049 2050 if (nla_put_u32(skb, MPTCP_ATTR_RESET_REASON, sf->reset_reason)) 2051 return -EMSGSIZE; 2052 2053 if (nla_put_u32(skb, MPTCP_ATTR_RESET_FLAGS, sf->reset_transient)) 2054 return -EMSGSIZE; 2055 2056 return 0; 2057 } 2058 2059 static int mptcp_event_created(struct sk_buff *skb, 2060 const struct mptcp_sock *msk, 2061 const struct sock *ssk) 2062 { 2063 int err = nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token); 2064 2065 if (err) 2066 return err; 2067 2068 if (nla_put_u8(skb, MPTCP_ATTR_SERVER_SIDE, READ_ONCE(msk->pm.server_side))) 2069 return -EMSGSIZE; 2070 2071 return mptcp_event_add_subflow(skb, ssk); 2072 } 2073 2074 void mptcp_event_addr_removed(const struct mptcp_sock *msk, uint8_t id) 2075 { 2076 struct net *net = sock_net((const struct sock *)msk); 2077 struct nlmsghdr *nlh; 2078 struct sk_buff *skb; 2079 2080 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2081 return; 2082 2083 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); 2084 if (!skb) 2085 return; 2086 2087 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, MPTCP_EVENT_REMOVED); 2088 if (!nlh) 2089 goto nla_put_failure; 2090 2091 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token)) 2092 goto nla_put_failure; 2093 2094 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, id)) 2095 goto nla_put_failure; 2096 2097 genlmsg_end(skb, nlh); 2098 mptcp_nl_mcast_send(net, skb, GFP_ATOMIC); 2099 return; 2100 2101 nla_put_failure: 2102 kfree_skb(skb); 2103 } 2104 2105 void mptcp_event_addr_announced(const struct sock *ssk, 2106 const struct mptcp_addr_info *info) 2107 { 2108 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 2109 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 2110 struct net *net = sock_net(ssk); 2111 struct nlmsghdr *nlh; 2112 struct sk_buff *skb; 2113 2114 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2115 return; 2116 2117 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); 2118 if (!skb) 2119 return; 2120 2121 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, 2122 MPTCP_EVENT_ANNOUNCED); 2123 if (!nlh) 2124 goto nla_put_failure; 2125 2126 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token)) 2127 goto nla_put_failure; 2128 2129 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, info->id)) 2130 goto nla_put_failure; 2131 2132 if (nla_put_be16(skb, MPTCP_ATTR_DPORT, 2133 info->port == 0 ? 2134 inet_sk(ssk)->inet_dport : 2135 info->port)) 2136 goto nla_put_failure; 2137 2138 switch (info->family) { 2139 case AF_INET: 2140 if (nla_put_in_addr(skb, MPTCP_ATTR_DADDR4, info->addr.s_addr)) 2141 goto nla_put_failure; 2142 break; 2143 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 2144 case AF_INET6: 2145 if (nla_put_in6_addr(skb, MPTCP_ATTR_DADDR6, &info->addr6)) 2146 goto nla_put_failure; 2147 break; 2148 #endif 2149 default: 2150 WARN_ON_ONCE(1); 2151 goto nla_put_failure; 2152 } 2153 2154 genlmsg_end(skb, nlh); 2155 mptcp_nl_mcast_send(net, skb, GFP_ATOMIC); 2156 return; 2157 2158 nla_put_failure: 2159 kfree_skb(skb); 2160 } 2161 2162 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk, 2163 const struct sock *ssk, gfp_t gfp) 2164 { 2165 struct net *net = sock_net((const struct sock *)msk); 2166 struct nlmsghdr *nlh; 2167 struct sk_buff *skb; 2168 2169 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2170 return; 2171 2172 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, gfp); 2173 if (!skb) 2174 return; 2175 2176 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, type); 2177 if (!nlh) 2178 goto nla_put_failure; 2179 2180 switch (type) { 2181 case MPTCP_EVENT_UNSPEC: 2182 WARN_ON_ONCE(1); 2183 break; 2184 case MPTCP_EVENT_CREATED: 2185 case MPTCP_EVENT_ESTABLISHED: 2186 if (mptcp_event_created(skb, msk, ssk) < 0) 2187 goto nla_put_failure; 2188 break; 2189 case MPTCP_EVENT_CLOSED: 2190 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token) < 0) 2191 goto nla_put_failure; 2192 break; 2193 case MPTCP_EVENT_ANNOUNCED: 2194 case MPTCP_EVENT_REMOVED: 2195 /* call mptcp_event_addr_announced()/removed instead */ 2196 WARN_ON_ONCE(1); 2197 break; 2198 case MPTCP_EVENT_SUB_ESTABLISHED: 2199 case MPTCP_EVENT_SUB_PRIORITY: 2200 if (mptcp_event_sub_established(skb, msk, ssk) < 0) 2201 goto nla_put_failure; 2202 break; 2203 case MPTCP_EVENT_SUB_CLOSED: 2204 if (mptcp_event_sub_closed(skb, msk, ssk) < 0) 2205 goto nla_put_failure; 2206 break; 2207 } 2208 2209 genlmsg_end(skb, nlh); 2210 mptcp_nl_mcast_send(net, skb, gfp); 2211 return; 2212 2213 nla_put_failure: 2214 kfree_skb(skb); 2215 } 2216 2217 static const struct genl_small_ops mptcp_pm_ops[] = { 2218 { 2219 .cmd = MPTCP_PM_CMD_ADD_ADDR, 2220 .doit = mptcp_nl_cmd_add_addr, 2221 .flags = GENL_ADMIN_PERM, 2222 }, 2223 { 2224 .cmd = MPTCP_PM_CMD_DEL_ADDR, 2225 .doit = mptcp_nl_cmd_del_addr, 2226 .flags = GENL_ADMIN_PERM, 2227 }, 2228 { 2229 .cmd = MPTCP_PM_CMD_FLUSH_ADDRS, 2230 .doit = mptcp_nl_cmd_flush_addrs, 2231 .flags = GENL_ADMIN_PERM, 2232 }, 2233 { 2234 .cmd = MPTCP_PM_CMD_GET_ADDR, 2235 .doit = mptcp_nl_cmd_get_addr, 2236 .dumpit = mptcp_nl_cmd_dump_addrs, 2237 }, 2238 { 2239 .cmd = MPTCP_PM_CMD_SET_LIMITS, 2240 .doit = mptcp_nl_cmd_set_limits, 2241 .flags = GENL_ADMIN_PERM, 2242 }, 2243 { 2244 .cmd = MPTCP_PM_CMD_GET_LIMITS, 2245 .doit = mptcp_nl_cmd_get_limits, 2246 }, 2247 { 2248 .cmd = MPTCP_PM_CMD_SET_FLAGS, 2249 .doit = mptcp_nl_cmd_set_flags, 2250 .flags = GENL_ADMIN_PERM, 2251 }, 2252 { 2253 .cmd = MPTCP_PM_CMD_ANNOUNCE, 2254 .doit = mptcp_nl_cmd_announce, 2255 .flags = GENL_ADMIN_PERM, 2256 }, 2257 { 2258 .cmd = MPTCP_PM_CMD_REMOVE, 2259 .doit = mptcp_nl_cmd_remove, 2260 .flags = GENL_ADMIN_PERM, 2261 }, 2262 { 2263 .cmd = MPTCP_PM_CMD_SUBFLOW_CREATE, 2264 .doit = mptcp_nl_cmd_sf_create, 2265 .flags = GENL_ADMIN_PERM, 2266 }, 2267 { 2268 .cmd = MPTCP_PM_CMD_SUBFLOW_DESTROY, 2269 .doit = mptcp_nl_cmd_sf_destroy, 2270 .flags = GENL_ADMIN_PERM, 2271 }, 2272 }; 2273 2274 static struct genl_family mptcp_genl_family __ro_after_init = { 2275 .name = MPTCP_PM_NAME, 2276 .version = MPTCP_PM_VER, 2277 .maxattr = MPTCP_PM_ATTR_MAX, 2278 .policy = mptcp_pm_policy, 2279 .netnsok = true, 2280 .module = THIS_MODULE, 2281 .small_ops = mptcp_pm_ops, 2282 .n_small_ops = ARRAY_SIZE(mptcp_pm_ops), 2283 .mcgrps = mptcp_pm_mcgrps, 2284 .n_mcgrps = ARRAY_SIZE(mptcp_pm_mcgrps), 2285 }; 2286 2287 static int __net_init pm_nl_init_net(struct net *net) 2288 { 2289 struct pm_nl_pernet *pernet = pm_nl_get_pernet(net); 2290 2291 INIT_LIST_HEAD_RCU(&pernet->local_addr_list); 2292 2293 /* Cit. 2 subflows ought to be enough for anybody. */ 2294 pernet->subflows_max = 2; 2295 pernet->next_id = 1; 2296 pernet->stale_loss_cnt = 4; 2297 spin_lock_init(&pernet->lock); 2298 2299 /* No need to initialize other pernet fields, the struct is zeroed at 2300 * allocation time. 2301 */ 2302 2303 return 0; 2304 } 2305 2306 static void __net_exit pm_nl_exit_net(struct list_head *net_list) 2307 { 2308 struct net *net; 2309 2310 list_for_each_entry(net, net_list, exit_list) { 2311 struct pm_nl_pernet *pernet = pm_nl_get_pernet(net); 2312 2313 /* net is removed from namespace list, can't race with 2314 * other modifiers, also netns core already waited for a 2315 * RCU grace period. 2316 */ 2317 __flush_addrs(&pernet->local_addr_list); 2318 } 2319 } 2320 2321 static struct pernet_operations mptcp_pm_pernet_ops = { 2322 .init = pm_nl_init_net, 2323 .exit_batch = pm_nl_exit_net, 2324 .id = &pm_nl_pernet_id, 2325 .size = sizeof(struct pm_nl_pernet), 2326 }; 2327 2328 void __init mptcp_pm_nl_init(void) 2329 { 2330 if (register_pernet_subsys(&mptcp_pm_pernet_ops) < 0) 2331 panic("Failed to register MPTCP PM pernet subsystem.\n"); 2332 2333 if (genl_register_family(&mptcp_genl_family)) 2334 panic("Failed to register MPTCP PM netlink family\n"); 2335 } 2336