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_addr_entry { 26 struct list_head list; 27 struct mptcp_addr_info addr; 28 u8 flags; 29 int ifindex; 30 struct socket *lsk; 31 }; 32 33 struct mptcp_pm_add_entry { 34 struct list_head list; 35 struct mptcp_addr_info addr; 36 struct timer_list add_timer; 37 struct mptcp_sock *sock; 38 u8 retrans_times; 39 }; 40 41 struct pm_nl_pernet { 42 /* protects pernet updates */ 43 spinlock_t lock; 44 struct list_head local_addr_list; 45 unsigned int addrs; 46 unsigned int stale_loss_cnt; 47 unsigned int add_addr_signal_max; 48 unsigned int add_addr_accept_max; 49 unsigned int local_addr_max; 50 unsigned int subflows_max; 51 unsigned int next_id; 52 DECLARE_BITMAP(id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); 53 }; 54 55 #define MPTCP_PM_ADDR_MAX 8 56 #define ADD_ADDR_RETRANS_MAX 3 57 58 static bool addresses_equal(const struct mptcp_addr_info *a, 59 const struct mptcp_addr_info *b, bool use_port) 60 { 61 bool addr_equals = false; 62 63 if (a->family == b->family) { 64 if (a->family == AF_INET) 65 addr_equals = a->addr.s_addr == b->addr.s_addr; 66 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 67 else 68 addr_equals = !ipv6_addr_cmp(&a->addr6, &b->addr6); 69 } else if (a->family == AF_INET) { 70 if (ipv6_addr_v4mapped(&b->addr6)) 71 addr_equals = a->addr.s_addr == b->addr6.s6_addr32[3]; 72 } else if (b->family == AF_INET) { 73 if (ipv6_addr_v4mapped(&a->addr6)) 74 addr_equals = a->addr6.s6_addr32[3] == b->addr.s_addr; 75 #endif 76 } 77 78 if (!addr_equals) 79 return false; 80 if (!use_port) 81 return true; 82 83 return a->port == b->port; 84 } 85 86 static bool address_zero(const struct mptcp_addr_info *addr) 87 { 88 struct mptcp_addr_info zero; 89 90 memset(&zero, 0, sizeof(zero)); 91 zero.family = addr->family; 92 93 return addresses_equal(addr, &zero, true); 94 } 95 96 static void local_address(const struct sock_common *skc, 97 struct mptcp_addr_info *addr) 98 { 99 addr->family = skc->skc_family; 100 addr->port = htons(skc->skc_num); 101 if (addr->family == AF_INET) 102 addr->addr.s_addr = skc->skc_rcv_saddr; 103 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 104 else if (addr->family == AF_INET6) 105 addr->addr6 = skc->skc_v6_rcv_saddr; 106 #endif 107 } 108 109 static void remote_address(const struct sock_common *skc, 110 struct mptcp_addr_info *addr) 111 { 112 addr->family = skc->skc_family; 113 addr->port = skc->skc_dport; 114 if (addr->family == AF_INET) 115 addr->addr.s_addr = skc->skc_daddr; 116 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 117 else if (addr->family == AF_INET6) 118 addr->addr6 = skc->skc_v6_daddr; 119 #endif 120 } 121 122 static bool lookup_subflow_by_saddr(const struct list_head *list, 123 struct mptcp_addr_info *saddr) 124 { 125 struct mptcp_subflow_context *subflow; 126 struct mptcp_addr_info cur; 127 struct sock_common *skc; 128 129 list_for_each_entry(subflow, list, node) { 130 skc = (struct sock_common *)mptcp_subflow_tcp_sock(subflow); 131 132 local_address(skc, &cur); 133 if (addresses_equal(&cur, saddr, saddr->port)) 134 return true; 135 } 136 137 return false; 138 } 139 140 static bool lookup_subflow_by_daddr(const struct list_head *list, 141 struct mptcp_addr_info *daddr) 142 { 143 struct mptcp_subflow_context *subflow; 144 struct mptcp_addr_info cur; 145 struct sock_common *skc; 146 147 list_for_each_entry(subflow, list, node) { 148 skc = (struct sock_common *)mptcp_subflow_tcp_sock(subflow); 149 150 remote_address(skc, &cur); 151 if (addresses_equal(&cur, daddr, daddr->port)) 152 return true; 153 } 154 155 return false; 156 } 157 158 static struct mptcp_pm_addr_entry * 159 select_local_address(const struct pm_nl_pernet *pernet, 160 struct mptcp_sock *msk) 161 { 162 struct mptcp_pm_addr_entry *entry, *ret = NULL; 163 struct sock *sk = (struct sock *)msk; 164 165 msk_owned_by_me(msk); 166 167 rcu_read_lock(); 168 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 169 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW)) 170 continue; 171 172 if (!test_bit(entry->addr.id, msk->pm.id_avail_bitmap)) 173 continue; 174 175 if (entry->addr.family != sk->sk_family) { 176 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 177 if ((entry->addr.family == AF_INET && 178 !ipv6_addr_v4mapped(&sk->sk_v6_daddr)) || 179 (sk->sk_family == AF_INET && 180 !ipv6_addr_v4mapped(&entry->addr.addr6))) 181 #endif 182 continue; 183 } 184 185 ret = entry; 186 break; 187 } 188 rcu_read_unlock(); 189 return ret; 190 } 191 192 static struct mptcp_pm_addr_entry * 193 select_signal_address(struct pm_nl_pernet *pernet, struct mptcp_sock *msk) 194 { 195 struct mptcp_pm_addr_entry *entry, *ret = NULL; 196 197 rcu_read_lock(); 198 /* do not keep any additional per socket state, just signal 199 * the address list in order. 200 * Note: removal from the local address list during the msk life-cycle 201 * can lead to additional addresses not being announced. 202 */ 203 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 204 if (!test_bit(entry->addr.id, msk->pm.id_avail_bitmap)) 205 continue; 206 207 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) 208 continue; 209 210 ret = entry; 211 break; 212 } 213 rcu_read_unlock(); 214 return ret; 215 } 216 217 unsigned int mptcp_pm_get_add_addr_signal_max(struct mptcp_sock *msk) 218 { 219 struct pm_nl_pernet *pernet; 220 221 pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id); 222 return READ_ONCE(pernet->add_addr_signal_max); 223 } 224 EXPORT_SYMBOL_GPL(mptcp_pm_get_add_addr_signal_max); 225 226 unsigned int mptcp_pm_get_add_addr_accept_max(struct mptcp_sock *msk) 227 { 228 struct pm_nl_pernet *pernet; 229 230 pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id); 231 return READ_ONCE(pernet->add_addr_accept_max); 232 } 233 EXPORT_SYMBOL_GPL(mptcp_pm_get_add_addr_accept_max); 234 235 unsigned int mptcp_pm_get_subflows_max(struct mptcp_sock *msk) 236 { 237 struct pm_nl_pernet *pernet; 238 239 pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id); 240 return READ_ONCE(pernet->subflows_max); 241 } 242 EXPORT_SYMBOL_GPL(mptcp_pm_get_subflows_max); 243 244 unsigned int mptcp_pm_get_local_addr_max(struct mptcp_sock *msk) 245 { 246 struct pm_nl_pernet *pernet; 247 248 pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id); 249 return READ_ONCE(pernet->local_addr_max); 250 } 251 EXPORT_SYMBOL_GPL(mptcp_pm_get_local_addr_max); 252 253 bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk) 254 { 255 struct pm_nl_pernet *pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id); 256 257 if (msk->pm.subflows == mptcp_pm_get_subflows_max(msk) || 258 (find_next_and_bit(pernet->id_bitmap, msk->pm.id_avail_bitmap, 259 MPTCP_PM_MAX_ADDR_ID + 1, 0) == MPTCP_PM_MAX_ADDR_ID + 1)) { 260 WRITE_ONCE(msk->pm.work_pending, false); 261 return false; 262 } 263 return true; 264 } 265 266 struct mptcp_pm_add_entry * 267 mptcp_lookup_anno_list_by_saddr(struct mptcp_sock *msk, 268 struct mptcp_addr_info *addr) 269 { 270 struct mptcp_pm_add_entry *entry; 271 272 lockdep_assert_held(&msk->pm.lock); 273 274 list_for_each_entry(entry, &msk->pm.anno_list, list) { 275 if (addresses_equal(&entry->addr, addr, true)) 276 return entry; 277 } 278 279 return NULL; 280 } 281 282 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk) 283 { 284 struct mptcp_pm_add_entry *entry; 285 struct mptcp_addr_info saddr; 286 bool ret = false; 287 288 local_address((struct sock_common *)sk, &saddr); 289 290 spin_lock_bh(&msk->pm.lock); 291 list_for_each_entry(entry, &msk->pm.anno_list, list) { 292 if (addresses_equal(&entry->addr, &saddr, true)) { 293 ret = true; 294 goto out; 295 } 296 } 297 298 out: 299 spin_unlock_bh(&msk->pm.lock); 300 return ret; 301 } 302 303 static void mptcp_pm_add_timer(struct timer_list *timer) 304 { 305 struct mptcp_pm_add_entry *entry = from_timer(entry, timer, add_timer); 306 struct mptcp_sock *msk = entry->sock; 307 struct sock *sk = (struct sock *)msk; 308 309 pr_debug("msk=%p", msk); 310 311 if (!msk) 312 return; 313 314 if (inet_sk_state_load(sk) == TCP_CLOSE) 315 return; 316 317 if (!entry->addr.id) 318 return; 319 320 if (mptcp_pm_should_add_signal_addr(msk)) { 321 sk_reset_timer(sk, timer, jiffies + TCP_RTO_MAX / 8); 322 goto out; 323 } 324 325 spin_lock_bh(&msk->pm.lock); 326 327 if (!mptcp_pm_should_add_signal_addr(msk)) { 328 pr_debug("retransmit ADD_ADDR id=%d", entry->addr.id); 329 mptcp_pm_announce_addr(msk, &entry->addr, false); 330 mptcp_pm_add_addr_send_ack(msk); 331 entry->retrans_times++; 332 } 333 334 if (entry->retrans_times < ADD_ADDR_RETRANS_MAX) 335 sk_reset_timer(sk, timer, 336 jiffies + mptcp_get_add_addr_timeout(sock_net(sk))); 337 338 spin_unlock_bh(&msk->pm.lock); 339 340 if (entry->retrans_times == ADD_ADDR_RETRANS_MAX) 341 mptcp_pm_subflow_established(msk); 342 343 out: 344 __sock_put(sk); 345 } 346 347 struct mptcp_pm_add_entry * 348 mptcp_pm_del_add_timer(struct mptcp_sock *msk, 349 struct mptcp_addr_info *addr, bool check_id) 350 { 351 struct mptcp_pm_add_entry *entry; 352 struct sock *sk = (struct sock *)msk; 353 354 spin_lock_bh(&msk->pm.lock); 355 entry = mptcp_lookup_anno_list_by_saddr(msk, addr); 356 if (entry && (!check_id || entry->addr.id == addr->id)) 357 entry->retrans_times = ADD_ADDR_RETRANS_MAX; 358 spin_unlock_bh(&msk->pm.lock); 359 360 if (entry && (!check_id || entry->addr.id == addr->id)) 361 sk_stop_timer_sync(sk, &entry->add_timer); 362 363 return entry; 364 } 365 366 static bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk, 367 struct mptcp_pm_addr_entry *entry) 368 { 369 struct mptcp_pm_add_entry *add_entry = NULL; 370 struct sock *sk = (struct sock *)msk; 371 struct net *net = sock_net(sk); 372 373 lockdep_assert_held(&msk->pm.lock); 374 375 if (mptcp_lookup_anno_list_by_saddr(msk, &entry->addr)) 376 return false; 377 378 add_entry = kmalloc(sizeof(*add_entry), GFP_ATOMIC); 379 if (!add_entry) 380 return false; 381 382 list_add(&add_entry->list, &msk->pm.anno_list); 383 384 add_entry->addr = entry->addr; 385 add_entry->sock = msk; 386 add_entry->retrans_times = 0; 387 388 timer_setup(&add_entry->add_timer, mptcp_pm_add_timer, 0); 389 sk_reset_timer(sk, &add_entry->add_timer, 390 jiffies + mptcp_get_add_addr_timeout(net)); 391 392 return true; 393 } 394 395 void mptcp_pm_free_anno_list(struct mptcp_sock *msk) 396 { 397 struct mptcp_pm_add_entry *entry, *tmp; 398 struct sock *sk = (struct sock *)msk; 399 LIST_HEAD(free_list); 400 401 pr_debug("msk=%p", msk); 402 403 spin_lock_bh(&msk->pm.lock); 404 list_splice_init(&msk->pm.anno_list, &free_list); 405 spin_unlock_bh(&msk->pm.lock); 406 407 list_for_each_entry_safe(entry, tmp, &free_list, list) { 408 sk_stop_timer_sync(sk, &entry->add_timer); 409 kfree(entry); 410 } 411 } 412 413 static bool lookup_address_in_vec(struct mptcp_addr_info *addrs, unsigned int nr, 414 struct mptcp_addr_info *addr) 415 { 416 int i; 417 418 for (i = 0; i < nr; i++) { 419 if (addresses_equal(&addrs[i], addr, addr->port)) 420 return true; 421 } 422 423 return false; 424 } 425 426 /* Fill all the remote addresses into the array addrs[], 427 * and return the array size. 428 */ 429 static unsigned int fill_remote_addresses_vec(struct mptcp_sock *msk, bool fullmesh, 430 struct mptcp_addr_info *addrs) 431 { 432 bool deny_id0 = READ_ONCE(msk->pm.remote_deny_join_id0); 433 struct sock *sk = (struct sock *)msk, *ssk; 434 struct mptcp_subflow_context *subflow; 435 struct mptcp_addr_info remote = { 0 }; 436 unsigned int subflows_max; 437 int i = 0; 438 439 subflows_max = mptcp_pm_get_subflows_max(msk); 440 remote_address((struct sock_common *)sk, &remote); 441 442 /* Non-fullmesh endpoint, fill in the single entry 443 * corresponding to the primary MPC subflow remote address 444 */ 445 if (!fullmesh) { 446 if (deny_id0) 447 return 0; 448 449 msk->pm.subflows++; 450 addrs[i++] = remote; 451 } else { 452 mptcp_for_each_subflow(msk, subflow) { 453 ssk = mptcp_subflow_tcp_sock(subflow); 454 remote_address((struct sock_common *)ssk, &addrs[i]); 455 if (deny_id0 && addresses_equal(&addrs[i], &remote, false)) 456 continue; 457 458 if (!lookup_address_in_vec(addrs, i, &addrs[i]) && 459 msk->pm.subflows < subflows_max) { 460 msk->pm.subflows++; 461 i++; 462 } 463 } 464 } 465 466 return i; 467 } 468 469 static struct mptcp_pm_addr_entry * 470 __lookup_addr_by_id(struct pm_nl_pernet *pernet, unsigned int id) 471 { 472 struct mptcp_pm_addr_entry *entry; 473 474 list_for_each_entry(entry, &pernet->local_addr_list, list) { 475 if (entry->addr.id == id) 476 return entry; 477 } 478 return NULL; 479 } 480 481 static struct mptcp_pm_addr_entry * 482 __lookup_addr(struct pm_nl_pernet *pernet, const struct mptcp_addr_info *info, 483 bool lookup_by_id) 484 { 485 struct mptcp_pm_addr_entry *entry; 486 487 list_for_each_entry(entry, &pernet->local_addr_list, list) { 488 if ((!lookup_by_id && addresses_equal(&entry->addr, info, true)) || 489 (lookup_by_id && entry->addr.id == info->id)) 490 return entry; 491 } 492 return NULL; 493 } 494 495 static int 496 lookup_id_by_addr(struct pm_nl_pernet *pernet, const struct mptcp_addr_info *addr) 497 { 498 struct mptcp_pm_addr_entry *entry; 499 int ret = -1; 500 501 rcu_read_lock(); 502 list_for_each_entry(entry, &pernet->local_addr_list, list) { 503 if (addresses_equal(&entry->addr, addr, entry->addr.port)) { 504 ret = entry->addr.id; 505 break; 506 } 507 } 508 rcu_read_unlock(); 509 return ret; 510 } 511 512 static void mptcp_pm_create_subflow_or_signal_addr(struct mptcp_sock *msk) 513 { 514 struct sock *sk = (struct sock *)msk; 515 struct mptcp_pm_addr_entry *local; 516 unsigned int add_addr_signal_max; 517 unsigned int local_addr_max; 518 struct pm_nl_pernet *pernet; 519 unsigned int subflows_max; 520 521 pernet = net_generic(sock_net(sk), pm_nl_pernet_id); 522 523 add_addr_signal_max = mptcp_pm_get_add_addr_signal_max(msk); 524 local_addr_max = mptcp_pm_get_local_addr_max(msk); 525 subflows_max = mptcp_pm_get_subflows_max(msk); 526 527 /* do lazy endpoint usage accounting for the MPC subflows */ 528 if (unlikely(!(msk->pm.status & BIT(MPTCP_PM_MPC_ENDPOINT_ACCOUNTED))) && msk->first) { 529 struct mptcp_addr_info mpc_addr; 530 int mpc_id; 531 532 local_address((struct sock_common *)msk->first, &mpc_addr); 533 mpc_id = lookup_id_by_addr(pernet, &mpc_addr); 534 if (mpc_id >= 0) 535 __clear_bit(mpc_id, msk->pm.id_avail_bitmap); 536 537 msk->pm.status |= BIT(MPTCP_PM_MPC_ENDPOINT_ACCOUNTED); 538 } 539 540 pr_debug("local %d:%d signal %d:%d subflows %d:%d\n", 541 msk->pm.local_addr_used, local_addr_max, 542 msk->pm.add_addr_signaled, add_addr_signal_max, 543 msk->pm.subflows, subflows_max); 544 545 /* check first for announce */ 546 if (msk->pm.add_addr_signaled < add_addr_signal_max) { 547 local = select_signal_address(pernet, msk); 548 549 if (local) { 550 if (mptcp_pm_alloc_anno_list(msk, local)) { 551 __clear_bit(local->addr.id, msk->pm.id_avail_bitmap); 552 msk->pm.add_addr_signaled++; 553 mptcp_pm_announce_addr(msk, &local->addr, false); 554 mptcp_pm_nl_addr_send_ack(msk); 555 } 556 } 557 } 558 559 /* check if should create a new subflow */ 560 while (msk->pm.local_addr_used < local_addr_max && 561 msk->pm.subflows < subflows_max) { 562 struct mptcp_addr_info addrs[MPTCP_PM_ADDR_MAX]; 563 bool fullmesh; 564 int i, nr; 565 566 local = select_local_address(pernet, msk); 567 if (!local) 568 break; 569 570 fullmesh = !!(local->flags & MPTCP_PM_ADDR_FLAG_FULLMESH); 571 572 msk->pm.local_addr_used++; 573 nr = fill_remote_addresses_vec(msk, fullmesh, addrs); 574 if (nr) 575 __clear_bit(local->addr.id, msk->pm.id_avail_bitmap); 576 spin_unlock_bh(&msk->pm.lock); 577 for (i = 0; i < nr; i++) 578 __mptcp_subflow_connect(sk, &local->addr, &addrs[i]); 579 spin_lock_bh(&msk->pm.lock); 580 } 581 mptcp_pm_nl_check_work_pending(msk); 582 } 583 584 static void mptcp_pm_nl_fully_established(struct mptcp_sock *msk) 585 { 586 mptcp_pm_create_subflow_or_signal_addr(msk); 587 } 588 589 static void mptcp_pm_nl_subflow_established(struct mptcp_sock *msk) 590 { 591 mptcp_pm_create_subflow_or_signal_addr(msk); 592 } 593 594 /* Fill all the local addresses into the array addrs[], 595 * and return the array size. 596 */ 597 static unsigned int fill_local_addresses_vec(struct mptcp_sock *msk, 598 struct mptcp_addr_info *addrs) 599 { 600 struct sock *sk = (struct sock *)msk; 601 struct mptcp_pm_addr_entry *entry; 602 struct mptcp_addr_info local; 603 struct pm_nl_pernet *pernet; 604 unsigned int subflows_max; 605 int i = 0; 606 607 pernet = net_generic(sock_net(sk), pm_nl_pernet_id); 608 subflows_max = mptcp_pm_get_subflows_max(msk); 609 610 rcu_read_lock(); 611 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 612 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_FULLMESH)) 613 continue; 614 615 if (entry->addr.family != sk->sk_family) { 616 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 617 if ((entry->addr.family == AF_INET && 618 !ipv6_addr_v4mapped(&sk->sk_v6_daddr)) || 619 (sk->sk_family == AF_INET && 620 !ipv6_addr_v4mapped(&entry->addr.addr6))) 621 #endif 622 continue; 623 } 624 625 if (msk->pm.subflows < subflows_max) { 626 msk->pm.subflows++; 627 addrs[i++] = entry->addr; 628 } 629 } 630 rcu_read_unlock(); 631 632 /* If the array is empty, fill in the single 633 * 'IPADDRANY' local address 634 */ 635 if (!i) { 636 memset(&local, 0, sizeof(local)); 637 local.family = msk->pm.remote.family; 638 639 msk->pm.subflows++; 640 addrs[i++] = local; 641 } 642 643 return i; 644 } 645 646 static void mptcp_pm_nl_add_addr_received(struct mptcp_sock *msk) 647 { 648 struct mptcp_addr_info addrs[MPTCP_PM_ADDR_MAX]; 649 struct sock *sk = (struct sock *)msk; 650 unsigned int add_addr_accept_max; 651 struct mptcp_addr_info remote; 652 unsigned int subflows_max; 653 int i, nr; 654 655 add_addr_accept_max = mptcp_pm_get_add_addr_accept_max(msk); 656 subflows_max = mptcp_pm_get_subflows_max(msk); 657 658 pr_debug("accepted %d:%d remote family %d", 659 msk->pm.add_addr_accepted, add_addr_accept_max, 660 msk->pm.remote.family); 661 662 if (lookup_subflow_by_daddr(&msk->conn_list, &msk->pm.remote)) 663 goto add_addr_echo; 664 665 /* connect to the specified remote address, using whatever 666 * local address the routing configuration will pick. 667 */ 668 remote = msk->pm.remote; 669 if (!remote.port) 670 remote.port = sk->sk_dport; 671 nr = fill_local_addresses_vec(msk, addrs); 672 673 msk->pm.add_addr_accepted++; 674 if (msk->pm.add_addr_accepted >= add_addr_accept_max || 675 msk->pm.subflows >= subflows_max) 676 WRITE_ONCE(msk->pm.accept_addr, false); 677 678 spin_unlock_bh(&msk->pm.lock); 679 for (i = 0; i < nr; i++) 680 __mptcp_subflow_connect(sk, &addrs[i], &remote); 681 spin_lock_bh(&msk->pm.lock); 682 683 add_addr_echo: 684 mptcp_pm_announce_addr(msk, &msk->pm.remote, true); 685 mptcp_pm_nl_addr_send_ack(msk); 686 } 687 688 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk) 689 { 690 struct mptcp_subflow_context *subflow; 691 692 msk_owned_by_me(msk); 693 lockdep_assert_held(&msk->pm.lock); 694 695 if (!mptcp_pm_should_add_signal(msk) && 696 !mptcp_pm_should_rm_signal(msk)) 697 return; 698 699 subflow = list_first_entry_or_null(&msk->conn_list, typeof(*subflow), node); 700 if (subflow) { 701 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 702 703 spin_unlock_bh(&msk->pm.lock); 704 pr_debug("send ack for %s", 705 mptcp_pm_should_add_signal(msk) ? "add_addr" : "rm_addr"); 706 707 mptcp_subflow_send_ack(ssk); 708 spin_lock_bh(&msk->pm.lock); 709 } 710 } 711 712 static int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk, 713 struct mptcp_addr_info *addr, 714 u8 bkup) 715 { 716 struct mptcp_subflow_context *subflow; 717 718 pr_debug("bkup=%d", bkup); 719 720 mptcp_for_each_subflow(msk, subflow) { 721 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 722 struct sock *sk = (struct sock *)msk; 723 struct mptcp_addr_info local; 724 725 local_address((struct sock_common *)ssk, &local); 726 if (!addresses_equal(&local, addr, addr->port)) 727 continue; 728 729 subflow->backup = bkup; 730 subflow->send_mp_prio = 1; 731 subflow->request_bkup = bkup; 732 __MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_MPPRIOTX); 733 734 spin_unlock_bh(&msk->pm.lock); 735 pr_debug("send ack for mp_prio"); 736 mptcp_subflow_send_ack(ssk); 737 spin_lock_bh(&msk->pm.lock); 738 739 return 0; 740 } 741 742 return -EINVAL; 743 } 744 745 static void mptcp_pm_nl_rm_addr_or_subflow(struct mptcp_sock *msk, 746 const struct mptcp_rm_list *rm_list, 747 enum linux_mptcp_mib_field rm_type) 748 { 749 struct mptcp_subflow_context *subflow, *tmp; 750 struct sock *sk = (struct sock *)msk; 751 u8 i; 752 753 pr_debug("%s rm_list_nr %d", 754 rm_type == MPTCP_MIB_RMADDR ? "address" : "subflow", rm_list->nr); 755 756 msk_owned_by_me(msk); 757 758 if (sk->sk_state == TCP_LISTEN) 759 return; 760 761 if (!rm_list->nr) 762 return; 763 764 if (list_empty(&msk->conn_list)) 765 return; 766 767 for (i = 0; i < rm_list->nr; i++) { 768 bool removed = false; 769 770 list_for_each_entry_safe(subflow, tmp, &msk->conn_list, node) { 771 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 772 int how = RCV_SHUTDOWN | SEND_SHUTDOWN; 773 u8 id = subflow->local_id; 774 775 if (rm_type == MPTCP_MIB_RMADDR) 776 id = subflow->remote_id; 777 778 if (rm_list->ids[i] != id) 779 continue; 780 781 pr_debug(" -> %s rm_list_ids[%d]=%u local_id=%u remote_id=%u", 782 rm_type == MPTCP_MIB_RMADDR ? "address" : "subflow", 783 i, rm_list->ids[i], subflow->local_id, subflow->remote_id); 784 spin_unlock_bh(&msk->pm.lock); 785 mptcp_subflow_shutdown(sk, ssk, how); 786 787 /* the following takes care of updating the subflows counter */ 788 mptcp_close_ssk(sk, ssk, subflow); 789 spin_lock_bh(&msk->pm.lock); 790 791 removed = true; 792 __MPTCP_INC_STATS(sock_net(sk), rm_type); 793 } 794 __set_bit(rm_list->ids[i], msk->pm.id_avail_bitmap); 795 if (!removed) 796 continue; 797 798 if (rm_type == MPTCP_MIB_RMADDR) { 799 msk->pm.add_addr_accepted--; 800 WRITE_ONCE(msk->pm.accept_addr, true); 801 } else if (rm_type == MPTCP_MIB_RMSUBFLOW) { 802 msk->pm.local_addr_used--; 803 } 804 } 805 } 806 807 static void mptcp_pm_nl_rm_addr_received(struct mptcp_sock *msk) 808 { 809 mptcp_pm_nl_rm_addr_or_subflow(msk, &msk->pm.rm_list_rx, MPTCP_MIB_RMADDR); 810 } 811 812 void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk, 813 const struct mptcp_rm_list *rm_list) 814 { 815 mptcp_pm_nl_rm_addr_or_subflow(msk, rm_list, MPTCP_MIB_RMSUBFLOW); 816 } 817 818 void mptcp_pm_nl_work(struct mptcp_sock *msk) 819 { 820 struct mptcp_pm_data *pm = &msk->pm; 821 822 msk_owned_by_me(msk); 823 824 if (!(pm->status & MPTCP_PM_WORK_MASK)) 825 return; 826 827 spin_lock_bh(&msk->pm.lock); 828 829 pr_debug("msk=%p status=%x", msk, pm->status); 830 if (pm->status & BIT(MPTCP_PM_ADD_ADDR_RECEIVED)) { 831 pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_RECEIVED); 832 mptcp_pm_nl_add_addr_received(msk); 833 } 834 if (pm->status & BIT(MPTCP_PM_ADD_ADDR_SEND_ACK)) { 835 pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_SEND_ACK); 836 mptcp_pm_nl_addr_send_ack(msk); 837 } 838 if (pm->status & BIT(MPTCP_PM_RM_ADDR_RECEIVED)) { 839 pm->status &= ~BIT(MPTCP_PM_RM_ADDR_RECEIVED); 840 mptcp_pm_nl_rm_addr_received(msk); 841 } 842 if (pm->status & BIT(MPTCP_PM_ESTABLISHED)) { 843 pm->status &= ~BIT(MPTCP_PM_ESTABLISHED); 844 mptcp_pm_nl_fully_established(msk); 845 } 846 if (pm->status & BIT(MPTCP_PM_SUBFLOW_ESTABLISHED)) { 847 pm->status &= ~BIT(MPTCP_PM_SUBFLOW_ESTABLISHED); 848 mptcp_pm_nl_subflow_established(msk); 849 } 850 851 spin_unlock_bh(&msk->pm.lock); 852 } 853 854 static bool address_use_port(struct mptcp_pm_addr_entry *entry) 855 { 856 return (entry->flags & 857 (MPTCP_PM_ADDR_FLAG_SIGNAL | MPTCP_PM_ADDR_FLAG_SUBFLOW)) == 858 MPTCP_PM_ADDR_FLAG_SIGNAL; 859 } 860 861 static int mptcp_pm_nl_append_new_local_addr(struct pm_nl_pernet *pernet, 862 struct mptcp_pm_addr_entry *entry) 863 { 864 struct mptcp_pm_addr_entry *cur; 865 unsigned int addr_max; 866 int ret = -EINVAL; 867 868 spin_lock_bh(&pernet->lock); 869 /* to keep the code simple, don't do IDR-like allocation for address ID, 870 * just bail when we exceed limits 871 */ 872 if (pernet->next_id == MPTCP_PM_MAX_ADDR_ID) 873 pernet->next_id = 1; 874 if (pernet->addrs >= MPTCP_PM_ADDR_MAX) 875 goto out; 876 if (test_bit(entry->addr.id, pernet->id_bitmap)) 877 goto out; 878 879 /* do not insert duplicate address, differentiate on port only 880 * singled addresses 881 */ 882 list_for_each_entry(cur, &pernet->local_addr_list, list) { 883 if (addresses_equal(&cur->addr, &entry->addr, 884 address_use_port(entry) && 885 address_use_port(cur))) 886 goto out; 887 } 888 889 if (!entry->addr.id) { 890 find_next: 891 entry->addr.id = find_next_zero_bit(pernet->id_bitmap, 892 MPTCP_PM_MAX_ADDR_ID + 1, 893 pernet->next_id); 894 if (!entry->addr.id && pernet->next_id != 1) { 895 pernet->next_id = 1; 896 goto find_next; 897 } 898 } 899 900 if (!entry->addr.id) 901 goto out; 902 903 __set_bit(entry->addr.id, pernet->id_bitmap); 904 if (entry->addr.id > pernet->next_id) 905 pernet->next_id = entry->addr.id; 906 907 if (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL) { 908 addr_max = pernet->add_addr_signal_max; 909 WRITE_ONCE(pernet->add_addr_signal_max, addr_max + 1); 910 } 911 if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) { 912 addr_max = pernet->local_addr_max; 913 WRITE_ONCE(pernet->local_addr_max, addr_max + 1); 914 } 915 916 pernet->addrs++; 917 list_add_tail_rcu(&entry->list, &pernet->local_addr_list); 918 ret = entry->addr.id; 919 920 out: 921 spin_unlock_bh(&pernet->lock); 922 return ret; 923 } 924 925 static int mptcp_pm_nl_create_listen_socket(struct sock *sk, 926 struct mptcp_pm_addr_entry *entry) 927 { 928 struct sockaddr_storage addr; 929 struct mptcp_sock *msk; 930 struct socket *ssock; 931 int backlog = 1024; 932 int err; 933 934 err = sock_create_kern(sock_net(sk), entry->addr.family, 935 SOCK_STREAM, IPPROTO_MPTCP, &entry->lsk); 936 if (err) 937 return err; 938 939 msk = mptcp_sk(entry->lsk->sk); 940 if (!msk) { 941 err = -EINVAL; 942 goto out; 943 } 944 945 ssock = __mptcp_nmpc_socket(msk); 946 if (!ssock) { 947 err = -EINVAL; 948 goto out; 949 } 950 951 mptcp_info2sockaddr(&entry->addr, &addr, entry->addr.family); 952 err = kernel_bind(ssock, (struct sockaddr *)&addr, 953 sizeof(struct sockaddr_in)); 954 if (err) { 955 pr_warn("kernel_bind error, err=%d", err); 956 goto out; 957 } 958 959 err = kernel_listen(ssock, backlog); 960 if (err) { 961 pr_warn("kernel_listen error, err=%d", err); 962 goto out; 963 } 964 965 return 0; 966 967 out: 968 sock_release(entry->lsk); 969 return err; 970 } 971 972 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct sock_common *skc) 973 { 974 struct mptcp_pm_addr_entry *entry; 975 struct mptcp_addr_info skc_local; 976 struct mptcp_addr_info msk_local; 977 struct pm_nl_pernet *pernet; 978 int ret = -1; 979 980 if (WARN_ON_ONCE(!msk)) 981 return -1; 982 983 /* The 0 ID mapping is defined by the first subflow, copied into the msk 984 * addr 985 */ 986 local_address((struct sock_common *)msk, &msk_local); 987 local_address((struct sock_common *)skc, &skc_local); 988 if (addresses_equal(&msk_local, &skc_local, false)) 989 return 0; 990 991 if (address_zero(&skc_local)) 992 return 0; 993 994 pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id); 995 996 rcu_read_lock(); 997 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 998 if (addresses_equal(&entry->addr, &skc_local, entry->addr.port)) { 999 ret = entry->addr.id; 1000 break; 1001 } 1002 } 1003 rcu_read_unlock(); 1004 if (ret >= 0) 1005 return ret; 1006 1007 /* address not found, add to local list */ 1008 entry = kmalloc(sizeof(*entry), GFP_ATOMIC); 1009 if (!entry) 1010 return -ENOMEM; 1011 1012 entry->addr = skc_local; 1013 entry->addr.id = 0; 1014 entry->addr.port = 0; 1015 entry->ifindex = 0; 1016 entry->flags = 0; 1017 entry->lsk = NULL; 1018 ret = mptcp_pm_nl_append_new_local_addr(pernet, entry); 1019 if (ret < 0) 1020 kfree(entry); 1021 1022 return ret; 1023 } 1024 1025 void mptcp_pm_nl_data_init(struct mptcp_sock *msk) 1026 { 1027 struct mptcp_pm_data *pm = &msk->pm; 1028 bool subflows; 1029 1030 subflows = !!mptcp_pm_get_subflows_max(msk); 1031 WRITE_ONCE(pm->work_pending, (!!mptcp_pm_get_local_addr_max(msk) && subflows) || 1032 !!mptcp_pm_get_add_addr_signal_max(msk)); 1033 WRITE_ONCE(pm->accept_addr, !!mptcp_pm_get_add_addr_accept_max(msk) && subflows); 1034 WRITE_ONCE(pm->accept_subflow, subflows); 1035 } 1036 1037 #define MPTCP_PM_CMD_GRP_OFFSET 0 1038 #define MPTCP_PM_EV_GRP_OFFSET 1 1039 1040 static const struct genl_multicast_group mptcp_pm_mcgrps[] = { 1041 [MPTCP_PM_CMD_GRP_OFFSET] = { .name = MPTCP_PM_CMD_GRP_NAME, }, 1042 [MPTCP_PM_EV_GRP_OFFSET] = { .name = MPTCP_PM_EV_GRP_NAME, 1043 .flags = GENL_UNS_ADMIN_PERM, 1044 }, 1045 }; 1046 1047 static const struct nla_policy 1048 mptcp_pm_addr_policy[MPTCP_PM_ADDR_ATTR_MAX + 1] = { 1049 [MPTCP_PM_ADDR_ATTR_FAMILY] = { .type = NLA_U16, }, 1050 [MPTCP_PM_ADDR_ATTR_ID] = { .type = NLA_U8, }, 1051 [MPTCP_PM_ADDR_ATTR_ADDR4] = { .type = NLA_U32, }, 1052 [MPTCP_PM_ADDR_ATTR_ADDR6] = 1053 NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)), 1054 [MPTCP_PM_ADDR_ATTR_PORT] = { .type = NLA_U16 }, 1055 [MPTCP_PM_ADDR_ATTR_FLAGS] = { .type = NLA_U32 }, 1056 [MPTCP_PM_ADDR_ATTR_IF_IDX] = { .type = NLA_S32 }, 1057 }; 1058 1059 static const struct nla_policy mptcp_pm_policy[MPTCP_PM_ATTR_MAX + 1] = { 1060 [MPTCP_PM_ATTR_ADDR] = 1061 NLA_POLICY_NESTED(mptcp_pm_addr_policy), 1062 [MPTCP_PM_ATTR_RCV_ADD_ADDRS] = { .type = NLA_U32, }, 1063 [MPTCP_PM_ATTR_SUBFLOWS] = { .type = NLA_U32, }, 1064 }; 1065 1066 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk) 1067 { 1068 struct mptcp_subflow_context *iter, *subflow = mptcp_subflow_ctx(ssk); 1069 struct sock *sk = (struct sock *)msk; 1070 unsigned int active_max_loss_cnt; 1071 struct net *net = sock_net(sk); 1072 unsigned int stale_loss_cnt; 1073 bool slow; 1074 1075 stale_loss_cnt = mptcp_stale_loss_cnt(net); 1076 if (subflow->stale || !stale_loss_cnt || subflow->stale_count <= stale_loss_cnt) 1077 return; 1078 1079 /* look for another available subflow not in loss state */ 1080 active_max_loss_cnt = max_t(int, stale_loss_cnt - 1, 1); 1081 mptcp_for_each_subflow(msk, iter) { 1082 if (iter != subflow && mptcp_subflow_active(iter) && 1083 iter->stale_count < active_max_loss_cnt) { 1084 /* we have some alternatives, try to mark this subflow as idle ...*/ 1085 slow = lock_sock_fast(ssk); 1086 if (!tcp_rtx_and_write_queues_empty(ssk)) { 1087 subflow->stale = 1; 1088 __mptcp_retransmit_pending_data(sk); 1089 MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_SUBFLOWSTALE); 1090 } 1091 unlock_sock_fast(ssk, slow); 1092 1093 /* always try to push the pending data regarless of re-injections: 1094 * we can possibly use backup subflows now, and subflow selection 1095 * is cheap under the msk socket lock 1096 */ 1097 __mptcp_push_pending(sk, 0); 1098 return; 1099 } 1100 } 1101 } 1102 1103 static int mptcp_pm_family_to_addr(int family) 1104 { 1105 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1106 if (family == AF_INET6) 1107 return MPTCP_PM_ADDR_ATTR_ADDR6; 1108 #endif 1109 return MPTCP_PM_ADDR_ATTR_ADDR4; 1110 } 1111 1112 static int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info, 1113 bool require_family, 1114 struct mptcp_pm_addr_entry *entry) 1115 { 1116 struct nlattr *tb[MPTCP_PM_ADDR_ATTR_MAX + 1]; 1117 int err, addr_addr; 1118 1119 if (!attr) { 1120 GENL_SET_ERR_MSG(info, "missing address info"); 1121 return -EINVAL; 1122 } 1123 1124 /* no validation needed - was already done via nested policy */ 1125 err = nla_parse_nested_deprecated(tb, MPTCP_PM_ADDR_ATTR_MAX, attr, 1126 mptcp_pm_addr_policy, info->extack); 1127 if (err) 1128 return err; 1129 1130 memset(entry, 0, sizeof(*entry)); 1131 if (!tb[MPTCP_PM_ADDR_ATTR_FAMILY]) { 1132 if (!require_family) 1133 goto skip_family; 1134 1135 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1136 "missing family"); 1137 return -EINVAL; 1138 } 1139 1140 entry->addr.family = nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_FAMILY]); 1141 if (entry->addr.family != AF_INET 1142 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1143 && entry->addr.family != AF_INET6 1144 #endif 1145 ) { 1146 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1147 "unknown address family"); 1148 return -EINVAL; 1149 } 1150 addr_addr = mptcp_pm_family_to_addr(entry->addr.family); 1151 if (!tb[addr_addr]) { 1152 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1153 "missing address data"); 1154 return -EINVAL; 1155 } 1156 1157 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1158 if (entry->addr.family == AF_INET6) 1159 entry->addr.addr6 = nla_get_in6_addr(tb[addr_addr]); 1160 else 1161 #endif 1162 entry->addr.addr.s_addr = nla_get_in_addr(tb[addr_addr]); 1163 1164 skip_family: 1165 if (tb[MPTCP_PM_ADDR_ATTR_IF_IDX]) { 1166 u32 val = nla_get_s32(tb[MPTCP_PM_ADDR_ATTR_IF_IDX]); 1167 1168 entry->ifindex = val; 1169 } 1170 1171 if (tb[MPTCP_PM_ADDR_ATTR_ID]) 1172 entry->addr.id = nla_get_u8(tb[MPTCP_PM_ADDR_ATTR_ID]); 1173 1174 if (tb[MPTCP_PM_ADDR_ATTR_FLAGS]) 1175 entry->flags = nla_get_u32(tb[MPTCP_PM_ADDR_ATTR_FLAGS]); 1176 1177 if (tb[MPTCP_PM_ADDR_ATTR_PORT]) { 1178 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) { 1179 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1180 "flags must have signal when using port"); 1181 return -EINVAL; 1182 } 1183 entry->addr.port = htons(nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_PORT])); 1184 } 1185 1186 return 0; 1187 } 1188 1189 static struct pm_nl_pernet *genl_info_pm_nl(struct genl_info *info) 1190 { 1191 return net_generic(genl_info_net(info), pm_nl_pernet_id); 1192 } 1193 1194 static int mptcp_nl_add_subflow_or_signal_addr(struct net *net) 1195 { 1196 struct mptcp_sock *msk; 1197 long s_slot = 0, s_num = 0; 1198 1199 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1200 struct sock *sk = (struct sock *)msk; 1201 1202 if (!READ_ONCE(msk->fully_established)) 1203 goto next; 1204 1205 lock_sock(sk); 1206 spin_lock_bh(&msk->pm.lock); 1207 mptcp_pm_create_subflow_or_signal_addr(msk); 1208 spin_unlock_bh(&msk->pm.lock); 1209 release_sock(sk); 1210 1211 next: 1212 sock_put(sk); 1213 cond_resched(); 1214 } 1215 1216 return 0; 1217 } 1218 1219 static int mptcp_nl_cmd_add_addr(struct sk_buff *skb, struct genl_info *info) 1220 { 1221 struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR]; 1222 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1223 struct mptcp_pm_addr_entry addr, *entry; 1224 int ret; 1225 1226 ret = mptcp_pm_parse_addr(attr, info, true, &addr); 1227 if (ret < 0) 1228 return ret; 1229 1230 entry = kmalloc(sizeof(*entry), GFP_KERNEL); 1231 if (!entry) { 1232 GENL_SET_ERR_MSG(info, "can't allocate addr"); 1233 return -ENOMEM; 1234 } 1235 1236 *entry = addr; 1237 if (entry->addr.port) { 1238 ret = mptcp_pm_nl_create_listen_socket(skb->sk, entry); 1239 if (ret) { 1240 GENL_SET_ERR_MSG(info, "create listen socket error"); 1241 kfree(entry); 1242 return ret; 1243 } 1244 } 1245 ret = mptcp_pm_nl_append_new_local_addr(pernet, entry); 1246 if (ret < 0) { 1247 GENL_SET_ERR_MSG(info, "too many addresses or duplicate one"); 1248 if (entry->lsk) 1249 sock_release(entry->lsk); 1250 kfree(entry); 1251 return ret; 1252 } 1253 1254 mptcp_nl_add_subflow_or_signal_addr(sock_net(skb->sk)); 1255 1256 return 0; 1257 } 1258 1259 int mptcp_pm_get_flags_and_ifindex_by_id(struct net *net, unsigned int id, 1260 u8 *flags, int *ifindex) 1261 { 1262 struct mptcp_pm_addr_entry *entry; 1263 1264 *flags = 0; 1265 *ifindex = 0; 1266 1267 if (id) { 1268 rcu_read_lock(); 1269 entry = __lookup_addr_by_id(net_generic(net, pm_nl_pernet_id), id); 1270 if (entry) { 1271 *flags = entry->flags; 1272 *ifindex = entry->ifindex; 1273 } 1274 rcu_read_unlock(); 1275 } 1276 1277 return 0; 1278 } 1279 1280 static bool remove_anno_list_by_saddr(struct mptcp_sock *msk, 1281 struct mptcp_addr_info *addr) 1282 { 1283 struct mptcp_pm_add_entry *entry; 1284 1285 entry = mptcp_pm_del_add_timer(msk, addr, false); 1286 if (entry) { 1287 list_del(&entry->list); 1288 kfree(entry); 1289 return true; 1290 } 1291 1292 return false; 1293 } 1294 1295 static bool mptcp_pm_remove_anno_addr(struct mptcp_sock *msk, 1296 struct mptcp_addr_info *addr, 1297 bool force) 1298 { 1299 struct mptcp_rm_list list = { .nr = 0 }; 1300 bool ret; 1301 1302 list.ids[list.nr++] = addr->id; 1303 1304 ret = remove_anno_list_by_saddr(msk, addr); 1305 if (ret || force) { 1306 spin_lock_bh(&msk->pm.lock); 1307 mptcp_pm_remove_addr(msk, &list); 1308 spin_unlock_bh(&msk->pm.lock); 1309 } 1310 return ret; 1311 } 1312 1313 static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net, 1314 struct mptcp_addr_info *addr) 1315 { 1316 struct mptcp_sock *msk; 1317 long s_slot = 0, s_num = 0; 1318 struct mptcp_rm_list list = { .nr = 0 }; 1319 1320 pr_debug("remove_id=%d", addr->id); 1321 1322 list.ids[list.nr++] = addr->id; 1323 1324 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1325 struct sock *sk = (struct sock *)msk; 1326 bool remove_subflow; 1327 1328 if (list_empty(&msk->conn_list)) { 1329 mptcp_pm_remove_anno_addr(msk, addr, false); 1330 goto next; 1331 } 1332 1333 lock_sock(sk); 1334 remove_subflow = lookup_subflow_by_saddr(&msk->conn_list, addr); 1335 mptcp_pm_remove_anno_addr(msk, addr, remove_subflow); 1336 if (remove_subflow) 1337 mptcp_pm_remove_subflow(msk, &list); 1338 release_sock(sk); 1339 1340 next: 1341 sock_put(sk); 1342 cond_resched(); 1343 } 1344 1345 return 0; 1346 } 1347 1348 /* caller must ensure the RCU grace period is already elapsed */ 1349 static void __mptcp_pm_release_addr_entry(struct mptcp_pm_addr_entry *entry) 1350 { 1351 if (entry->lsk) 1352 sock_release(entry->lsk); 1353 kfree(entry); 1354 } 1355 1356 static int mptcp_nl_remove_id_zero_address(struct net *net, 1357 struct mptcp_addr_info *addr) 1358 { 1359 struct mptcp_rm_list list = { .nr = 0 }; 1360 long s_slot = 0, s_num = 0; 1361 struct mptcp_sock *msk; 1362 1363 list.ids[list.nr++] = 0; 1364 1365 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1366 struct sock *sk = (struct sock *)msk; 1367 struct mptcp_addr_info msk_local; 1368 1369 if (list_empty(&msk->conn_list)) 1370 goto next; 1371 1372 local_address((struct sock_common *)msk, &msk_local); 1373 if (!addresses_equal(&msk_local, addr, addr->port)) 1374 goto next; 1375 1376 lock_sock(sk); 1377 spin_lock_bh(&msk->pm.lock); 1378 mptcp_pm_remove_addr(msk, &list); 1379 mptcp_pm_nl_rm_subflow_received(msk, &list); 1380 spin_unlock_bh(&msk->pm.lock); 1381 release_sock(sk); 1382 1383 next: 1384 sock_put(sk); 1385 cond_resched(); 1386 } 1387 1388 return 0; 1389 } 1390 1391 static int mptcp_nl_cmd_del_addr(struct sk_buff *skb, struct genl_info *info) 1392 { 1393 struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR]; 1394 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1395 struct mptcp_pm_addr_entry addr, *entry; 1396 unsigned int addr_max; 1397 int ret; 1398 1399 ret = mptcp_pm_parse_addr(attr, info, false, &addr); 1400 if (ret < 0) 1401 return ret; 1402 1403 /* the zero id address is special: the first address used by the msk 1404 * always gets such an id, so different subflows can have different zero 1405 * id addresses. Additionally zero id is not accounted for in id_bitmap. 1406 * Let's use an 'mptcp_rm_list' instead of the common remove code. 1407 */ 1408 if (addr.addr.id == 0) 1409 return mptcp_nl_remove_id_zero_address(sock_net(skb->sk), &addr.addr); 1410 1411 spin_lock_bh(&pernet->lock); 1412 entry = __lookup_addr_by_id(pernet, addr.addr.id); 1413 if (!entry) { 1414 GENL_SET_ERR_MSG(info, "address not found"); 1415 spin_unlock_bh(&pernet->lock); 1416 return -EINVAL; 1417 } 1418 if (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL) { 1419 addr_max = pernet->add_addr_signal_max; 1420 WRITE_ONCE(pernet->add_addr_signal_max, addr_max - 1); 1421 } 1422 if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) { 1423 addr_max = pernet->local_addr_max; 1424 WRITE_ONCE(pernet->local_addr_max, addr_max - 1); 1425 } 1426 1427 pernet->addrs--; 1428 list_del_rcu(&entry->list); 1429 __clear_bit(entry->addr.id, pernet->id_bitmap); 1430 spin_unlock_bh(&pernet->lock); 1431 1432 mptcp_nl_remove_subflow_and_signal_addr(sock_net(skb->sk), &entry->addr); 1433 synchronize_rcu(); 1434 __mptcp_pm_release_addr_entry(entry); 1435 1436 return ret; 1437 } 1438 1439 static void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk, 1440 struct list_head *rm_list) 1441 { 1442 struct mptcp_rm_list alist = { .nr = 0 }, slist = { .nr = 0 }; 1443 struct mptcp_pm_addr_entry *entry; 1444 1445 list_for_each_entry(entry, rm_list, list) { 1446 if (lookup_subflow_by_saddr(&msk->conn_list, &entry->addr) && 1447 alist.nr < MPTCP_RM_IDS_MAX && 1448 slist.nr < MPTCP_RM_IDS_MAX) { 1449 alist.ids[alist.nr++] = entry->addr.id; 1450 slist.ids[slist.nr++] = entry->addr.id; 1451 } else if (remove_anno_list_by_saddr(msk, &entry->addr) && 1452 alist.nr < MPTCP_RM_IDS_MAX) { 1453 alist.ids[alist.nr++] = entry->addr.id; 1454 } 1455 } 1456 1457 if (alist.nr) { 1458 spin_lock_bh(&msk->pm.lock); 1459 mptcp_pm_remove_addr(msk, &alist); 1460 spin_unlock_bh(&msk->pm.lock); 1461 } 1462 if (slist.nr) 1463 mptcp_pm_remove_subflow(msk, &slist); 1464 } 1465 1466 static void mptcp_nl_remove_addrs_list(struct net *net, 1467 struct list_head *rm_list) 1468 { 1469 long s_slot = 0, s_num = 0; 1470 struct mptcp_sock *msk; 1471 1472 if (list_empty(rm_list)) 1473 return; 1474 1475 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1476 struct sock *sk = (struct sock *)msk; 1477 1478 lock_sock(sk); 1479 mptcp_pm_remove_addrs_and_subflows(msk, rm_list); 1480 release_sock(sk); 1481 1482 sock_put(sk); 1483 cond_resched(); 1484 } 1485 } 1486 1487 /* caller must ensure the RCU grace period is already elapsed */ 1488 static void __flush_addrs(struct list_head *list) 1489 { 1490 while (!list_empty(list)) { 1491 struct mptcp_pm_addr_entry *cur; 1492 1493 cur = list_entry(list->next, 1494 struct mptcp_pm_addr_entry, list); 1495 list_del_rcu(&cur->list); 1496 __mptcp_pm_release_addr_entry(cur); 1497 } 1498 } 1499 1500 static void __reset_counters(struct pm_nl_pernet *pernet) 1501 { 1502 WRITE_ONCE(pernet->add_addr_signal_max, 0); 1503 WRITE_ONCE(pernet->add_addr_accept_max, 0); 1504 WRITE_ONCE(pernet->local_addr_max, 0); 1505 pernet->addrs = 0; 1506 } 1507 1508 static int mptcp_nl_cmd_flush_addrs(struct sk_buff *skb, struct genl_info *info) 1509 { 1510 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1511 LIST_HEAD(free_list); 1512 1513 spin_lock_bh(&pernet->lock); 1514 list_splice_init(&pernet->local_addr_list, &free_list); 1515 __reset_counters(pernet); 1516 pernet->next_id = 1; 1517 bitmap_zero(pernet->id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); 1518 spin_unlock_bh(&pernet->lock); 1519 mptcp_nl_remove_addrs_list(sock_net(skb->sk), &free_list); 1520 synchronize_rcu(); 1521 __flush_addrs(&free_list); 1522 return 0; 1523 } 1524 1525 static int mptcp_nl_fill_addr(struct sk_buff *skb, 1526 struct mptcp_pm_addr_entry *entry) 1527 { 1528 struct mptcp_addr_info *addr = &entry->addr; 1529 struct nlattr *attr; 1530 1531 attr = nla_nest_start(skb, MPTCP_PM_ATTR_ADDR); 1532 if (!attr) 1533 return -EMSGSIZE; 1534 1535 if (nla_put_u16(skb, MPTCP_PM_ADDR_ATTR_FAMILY, addr->family)) 1536 goto nla_put_failure; 1537 if (nla_put_u16(skb, MPTCP_PM_ADDR_ATTR_PORT, ntohs(addr->port))) 1538 goto nla_put_failure; 1539 if (nla_put_u8(skb, MPTCP_PM_ADDR_ATTR_ID, addr->id)) 1540 goto nla_put_failure; 1541 if (nla_put_u32(skb, MPTCP_PM_ADDR_ATTR_FLAGS, entry->flags)) 1542 goto nla_put_failure; 1543 if (entry->ifindex && 1544 nla_put_s32(skb, MPTCP_PM_ADDR_ATTR_IF_IDX, entry->ifindex)) 1545 goto nla_put_failure; 1546 1547 if (addr->family == AF_INET && 1548 nla_put_in_addr(skb, MPTCP_PM_ADDR_ATTR_ADDR4, 1549 addr->addr.s_addr)) 1550 goto nla_put_failure; 1551 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1552 else if (addr->family == AF_INET6 && 1553 nla_put_in6_addr(skb, MPTCP_PM_ADDR_ATTR_ADDR6, &addr->addr6)) 1554 goto nla_put_failure; 1555 #endif 1556 nla_nest_end(skb, attr); 1557 return 0; 1558 1559 nla_put_failure: 1560 nla_nest_cancel(skb, attr); 1561 return -EMSGSIZE; 1562 } 1563 1564 static int mptcp_nl_cmd_get_addr(struct sk_buff *skb, struct genl_info *info) 1565 { 1566 struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR]; 1567 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1568 struct mptcp_pm_addr_entry addr, *entry; 1569 struct sk_buff *msg; 1570 void *reply; 1571 int ret; 1572 1573 ret = mptcp_pm_parse_addr(attr, info, false, &addr); 1574 if (ret < 0) 1575 return ret; 1576 1577 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 1578 if (!msg) 1579 return -ENOMEM; 1580 1581 reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0, 1582 info->genlhdr->cmd); 1583 if (!reply) { 1584 GENL_SET_ERR_MSG(info, "not enough space in Netlink message"); 1585 ret = -EMSGSIZE; 1586 goto fail; 1587 } 1588 1589 spin_lock_bh(&pernet->lock); 1590 entry = __lookup_addr_by_id(pernet, addr.addr.id); 1591 if (!entry) { 1592 GENL_SET_ERR_MSG(info, "address not found"); 1593 ret = -EINVAL; 1594 goto unlock_fail; 1595 } 1596 1597 ret = mptcp_nl_fill_addr(msg, entry); 1598 if (ret) 1599 goto unlock_fail; 1600 1601 genlmsg_end(msg, reply); 1602 ret = genlmsg_reply(msg, info); 1603 spin_unlock_bh(&pernet->lock); 1604 return ret; 1605 1606 unlock_fail: 1607 spin_unlock_bh(&pernet->lock); 1608 1609 fail: 1610 nlmsg_free(msg); 1611 return ret; 1612 } 1613 1614 static int mptcp_nl_cmd_dump_addrs(struct sk_buff *msg, 1615 struct netlink_callback *cb) 1616 { 1617 struct net *net = sock_net(msg->sk); 1618 struct mptcp_pm_addr_entry *entry; 1619 struct pm_nl_pernet *pernet; 1620 int id = cb->args[0]; 1621 void *hdr; 1622 int i; 1623 1624 pernet = net_generic(net, pm_nl_pernet_id); 1625 1626 spin_lock_bh(&pernet->lock); 1627 for (i = id; i < MPTCP_PM_MAX_ADDR_ID + 1; i++) { 1628 if (test_bit(i, pernet->id_bitmap)) { 1629 entry = __lookup_addr_by_id(pernet, i); 1630 if (!entry) 1631 break; 1632 1633 if (entry->addr.id <= id) 1634 continue; 1635 1636 hdr = genlmsg_put(msg, NETLINK_CB(cb->skb).portid, 1637 cb->nlh->nlmsg_seq, &mptcp_genl_family, 1638 NLM_F_MULTI, MPTCP_PM_CMD_GET_ADDR); 1639 if (!hdr) 1640 break; 1641 1642 if (mptcp_nl_fill_addr(msg, entry) < 0) { 1643 genlmsg_cancel(msg, hdr); 1644 break; 1645 } 1646 1647 id = entry->addr.id; 1648 genlmsg_end(msg, hdr); 1649 } 1650 } 1651 spin_unlock_bh(&pernet->lock); 1652 1653 cb->args[0] = id; 1654 return msg->len; 1655 } 1656 1657 static int parse_limit(struct genl_info *info, int id, unsigned int *limit) 1658 { 1659 struct nlattr *attr = info->attrs[id]; 1660 1661 if (!attr) 1662 return 0; 1663 1664 *limit = nla_get_u32(attr); 1665 if (*limit > MPTCP_PM_ADDR_MAX) { 1666 GENL_SET_ERR_MSG(info, "limit greater than maximum"); 1667 return -EINVAL; 1668 } 1669 return 0; 1670 } 1671 1672 static int 1673 mptcp_nl_cmd_set_limits(struct sk_buff *skb, struct genl_info *info) 1674 { 1675 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1676 unsigned int rcv_addrs, subflows; 1677 int ret; 1678 1679 spin_lock_bh(&pernet->lock); 1680 rcv_addrs = pernet->add_addr_accept_max; 1681 ret = parse_limit(info, MPTCP_PM_ATTR_RCV_ADD_ADDRS, &rcv_addrs); 1682 if (ret) 1683 goto unlock; 1684 1685 subflows = pernet->subflows_max; 1686 ret = parse_limit(info, MPTCP_PM_ATTR_SUBFLOWS, &subflows); 1687 if (ret) 1688 goto unlock; 1689 1690 WRITE_ONCE(pernet->add_addr_accept_max, rcv_addrs); 1691 WRITE_ONCE(pernet->subflows_max, subflows); 1692 1693 unlock: 1694 spin_unlock_bh(&pernet->lock); 1695 return ret; 1696 } 1697 1698 static int 1699 mptcp_nl_cmd_get_limits(struct sk_buff *skb, struct genl_info *info) 1700 { 1701 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1702 struct sk_buff *msg; 1703 void *reply; 1704 1705 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 1706 if (!msg) 1707 return -ENOMEM; 1708 1709 reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0, 1710 MPTCP_PM_CMD_GET_LIMITS); 1711 if (!reply) 1712 goto fail; 1713 1714 if (nla_put_u32(msg, MPTCP_PM_ATTR_RCV_ADD_ADDRS, 1715 READ_ONCE(pernet->add_addr_accept_max))) 1716 goto fail; 1717 1718 if (nla_put_u32(msg, MPTCP_PM_ATTR_SUBFLOWS, 1719 READ_ONCE(pernet->subflows_max))) 1720 goto fail; 1721 1722 genlmsg_end(msg, reply); 1723 return genlmsg_reply(msg, info); 1724 1725 fail: 1726 GENL_SET_ERR_MSG(info, "not enough space in Netlink message"); 1727 nlmsg_free(msg); 1728 return -EMSGSIZE; 1729 } 1730 1731 static int mptcp_nl_addr_backup(struct net *net, 1732 struct mptcp_addr_info *addr, 1733 u8 bkup) 1734 { 1735 long s_slot = 0, s_num = 0; 1736 struct mptcp_sock *msk; 1737 int ret = -EINVAL; 1738 1739 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1740 struct sock *sk = (struct sock *)msk; 1741 1742 if (list_empty(&msk->conn_list)) 1743 goto next; 1744 1745 lock_sock(sk); 1746 spin_lock_bh(&msk->pm.lock); 1747 ret = mptcp_pm_nl_mp_prio_send_ack(msk, addr, bkup); 1748 spin_unlock_bh(&msk->pm.lock); 1749 release_sock(sk); 1750 1751 next: 1752 sock_put(sk); 1753 cond_resched(); 1754 } 1755 1756 return ret; 1757 } 1758 1759 static int mptcp_nl_cmd_set_flags(struct sk_buff *skb, struct genl_info *info) 1760 { 1761 struct mptcp_pm_addr_entry addr = { .addr = { .family = AF_UNSPEC }, }, *entry; 1762 struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR]; 1763 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1764 struct net *net = sock_net(skb->sk); 1765 u8 bkup = 0, lookup_by_id = 0; 1766 int ret; 1767 1768 ret = mptcp_pm_parse_addr(attr, info, false, &addr); 1769 if (ret < 0) 1770 return ret; 1771 1772 if (addr.flags & MPTCP_PM_ADDR_FLAG_BACKUP) 1773 bkup = 1; 1774 if (addr.addr.family == AF_UNSPEC) { 1775 lookup_by_id = 1; 1776 if (!addr.addr.id) 1777 return -EOPNOTSUPP; 1778 } 1779 1780 spin_lock_bh(&pernet->lock); 1781 entry = __lookup_addr(pernet, &addr.addr, lookup_by_id); 1782 if (!entry) { 1783 spin_unlock_bh(&pernet->lock); 1784 return -EINVAL; 1785 } 1786 1787 if (bkup) 1788 entry->flags |= MPTCP_PM_ADDR_FLAG_BACKUP; 1789 else 1790 entry->flags &= ~MPTCP_PM_ADDR_FLAG_BACKUP; 1791 addr = *entry; 1792 spin_unlock_bh(&pernet->lock); 1793 1794 mptcp_nl_addr_backup(net, &addr.addr, bkup); 1795 return 0; 1796 } 1797 1798 static void mptcp_nl_mcast_send(struct net *net, struct sk_buff *nlskb, gfp_t gfp) 1799 { 1800 genlmsg_multicast_netns(&mptcp_genl_family, net, 1801 nlskb, 0, MPTCP_PM_EV_GRP_OFFSET, gfp); 1802 } 1803 1804 static int mptcp_event_add_subflow(struct sk_buff *skb, const struct sock *ssk) 1805 { 1806 const struct inet_sock *issk = inet_sk(ssk); 1807 const struct mptcp_subflow_context *sf; 1808 1809 if (nla_put_u16(skb, MPTCP_ATTR_FAMILY, ssk->sk_family)) 1810 return -EMSGSIZE; 1811 1812 switch (ssk->sk_family) { 1813 case AF_INET: 1814 if (nla_put_in_addr(skb, MPTCP_ATTR_SADDR4, issk->inet_saddr)) 1815 return -EMSGSIZE; 1816 if (nla_put_in_addr(skb, MPTCP_ATTR_DADDR4, issk->inet_daddr)) 1817 return -EMSGSIZE; 1818 break; 1819 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1820 case AF_INET6: { 1821 const struct ipv6_pinfo *np = inet6_sk(ssk); 1822 1823 if (nla_put_in6_addr(skb, MPTCP_ATTR_SADDR6, &np->saddr)) 1824 return -EMSGSIZE; 1825 if (nla_put_in6_addr(skb, MPTCP_ATTR_DADDR6, &ssk->sk_v6_daddr)) 1826 return -EMSGSIZE; 1827 break; 1828 } 1829 #endif 1830 default: 1831 WARN_ON_ONCE(1); 1832 return -EMSGSIZE; 1833 } 1834 1835 if (nla_put_be16(skb, MPTCP_ATTR_SPORT, issk->inet_sport)) 1836 return -EMSGSIZE; 1837 if (nla_put_be16(skb, MPTCP_ATTR_DPORT, issk->inet_dport)) 1838 return -EMSGSIZE; 1839 1840 sf = mptcp_subflow_ctx(ssk); 1841 if (WARN_ON_ONCE(!sf)) 1842 return -EINVAL; 1843 1844 if (nla_put_u8(skb, MPTCP_ATTR_LOC_ID, sf->local_id)) 1845 return -EMSGSIZE; 1846 1847 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, sf->remote_id)) 1848 return -EMSGSIZE; 1849 1850 return 0; 1851 } 1852 1853 static int mptcp_event_put_token_and_ssk(struct sk_buff *skb, 1854 const struct mptcp_sock *msk, 1855 const struct sock *ssk) 1856 { 1857 const struct sock *sk = (const struct sock *)msk; 1858 const struct mptcp_subflow_context *sf; 1859 u8 sk_err; 1860 1861 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token)) 1862 return -EMSGSIZE; 1863 1864 if (mptcp_event_add_subflow(skb, ssk)) 1865 return -EMSGSIZE; 1866 1867 sf = mptcp_subflow_ctx(ssk); 1868 if (WARN_ON_ONCE(!sf)) 1869 return -EINVAL; 1870 1871 if (nla_put_u8(skb, MPTCP_ATTR_BACKUP, sf->backup)) 1872 return -EMSGSIZE; 1873 1874 if (ssk->sk_bound_dev_if && 1875 nla_put_s32(skb, MPTCP_ATTR_IF_IDX, ssk->sk_bound_dev_if)) 1876 return -EMSGSIZE; 1877 1878 sk_err = ssk->sk_err; 1879 if (sk_err && sk->sk_state == TCP_ESTABLISHED && 1880 nla_put_u8(skb, MPTCP_ATTR_ERROR, sk_err)) 1881 return -EMSGSIZE; 1882 1883 return 0; 1884 } 1885 1886 static int mptcp_event_sub_established(struct sk_buff *skb, 1887 const struct mptcp_sock *msk, 1888 const struct sock *ssk) 1889 { 1890 return mptcp_event_put_token_and_ssk(skb, msk, ssk); 1891 } 1892 1893 static int mptcp_event_sub_closed(struct sk_buff *skb, 1894 const struct mptcp_sock *msk, 1895 const struct sock *ssk) 1896 { 1897 const struct mptcp_subflow_context *sf; 1898 1899 if (mptcp_event_put_token_and_ssk(skb, msk, ssk)) 1900 return -EMSGSIZE; 1901 1902 sf = mptcp_subflow_ctx(ssk); 1903 if (!sf->reset_seen) 1904 return 0; 1905 1906 if (nla_put_u32(skb, MPTCP_ATTR_RESET_REASON, sf->reset_reason)) 1907 return -EMSGSIZE; 1908 1909 if (nla_put_u32(skb, MPTCP_ATTR_RESET_FLAGS, sf->reset_transient)) 1910 return -EMSGSIZE; 1911 1912 return 0; 1913 } 1914 1915 static int mptcp_event_created(struct sk_buff *skb, 1916 const struct mptcp_sock *msk, 1917 const struct sock *ssk) 1918 { 1919 int err = nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token); 1920 1921 if (err) 1922 return err; 1923 1924 return mptcp_event_add_subflow(skb, ssk); 1925 } 1926 1927 void mptcp_event_addr_removed(const struct mptcp_sock *msk, uint8_t id) 1928 { 1929 struct net *net = sock_net((const struct sock *)msk); 1930 struct nlmsghdr *nlh; 1931 struct sk_buff *skb; 1932 1933 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 1934 return; 1935 1936 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); 1937 if (!skb) 1938 return; 1939 1940 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, MPTCP_EVENT_REMOVED); 1941 if (!nlh) 1942 goto nla_put_failure; 1943 1944 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token)) 1945 goto nla_put_failure; 1946 1947 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, id)) 1948 goto nla_put_failure; 1949 1950 genlmsg_end(skb, nlh); 1951 mptcp_nl_mcast_send(net, skb, GFP_ATOMIC); 1952 return; 1953 1954 nla_put_failure: 1955 kfree_skb(skb); 1956 } 1957 1958 void mptcp_event_addr_announced(const struct mptcp_sock *msk, 1959 const struct mptcp_addr_info *info) 1960 { 1961 struct net *net = sock_net((const struct sock *)msk); 1962 struct nlmsghdr *nlh; 1963 struct sk_buff *skb; 1964 1965 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 1966 return; 1967 1968 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); 1969 if (!skb) 1970 return; 1971 1972 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, 1973 MPTCP_EVENT_ANNOUNCED); 1974 if (!nlh) 1975 goto nla_put_failure; 1976 1977 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token)) 1978 goto nla_put_failure; 1979 1980 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, info->id)) 1981 goto nla_put_failure; 1982 1983 if (nla_put_be16(skb, MPTCP_ATTR_DPORT, info->port)) 1984 goto nla_put_failure; 1985 1986 switch (info->family) { 1987 case AF_INET: 1988 if (nla_put_in_addr(skb, MPTCP_ATTR_DADDR4, info->addr.s_addr)) 1989 goto nla_put_failure; 1990 break; 1991 #if IS_ENABLED(CONFIG_MPTCP_IPV6) 1992 case AF_INET6: 1993 if (nla_put_in6_addr(skb, MPTCP_ATTR_DADDR6, &info->addr6)) 1994 goto nla_put_failure; 1995 break; 1996 #endif 1997 default: 1998 WARN_ON_ONCE(1); 1999 goto nla_put_failure; 2000 } 2001 2002 genlmsg_end(skb, nlh); 2003 mptcp_nl_mcast_send(net, skb, GFP_ATOMIC); 2004 return; 2005 2006 nla_put_failure: 2007 kfree_skb(skb); 2008 } 2009 2010 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk, 2011 const struct sock *ssk, gfp_t gfp) 2012 { 2013 struct net *net = sock_net((const struct sock *)msk); 2014 struct nlmsghdr *nlh; 2015 struct sk_buff *skb; 2016 2017 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2018 return; 2019 2020 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, gfp); 2021 if (!skb) 2022 return; 2023 2024 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, type); 2025 if (!nlh) 2026 goto nla_put_failure; 2027 2028 switch (type) { 2029 case MPTCP_EVENT_UNSPEC: 2030 WARN_ON_ONCE(1); 2031 break; 2032 case MPTCP_EVENT_CREATED: 2033 case MPTCP_EVENT_ESTABLISHED: 2034 if (mptcp_event_created(skb, msk, ssk) < 0) 2035 goto nla_put_failure; 2036 break; 2037 case MPTCP_EVENT_CLOSED: 2038 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token) < 0) 2039 goto nla_put_failure; 2040 break; 2041 case MPTCP_EVENT_ANNOUNCED: 2042 case MPTCP_EVENT_REMOVED: 2043 /* call mptcp_event_addr_announced()/removed instead */ 2044 WARN_ON_ONCE(1); 2045 break; 2046 case MPTCP_EVENT_SUB_ESTABLISHED: 2047 case MPTCP_EVENT_SUB_PRIORITY: 2048 if (mptcp_event_sub_established(skb, msk, ssk) < 0) 2049 goto nla_put_failure; 2050 break; 2051 case MPTCP_EVENT_SUB_CLOSED: 2052 if (mptcp_event_sub_closed(skb, msk, ssk) < 0) 2053 goto nla_put_failure; 2054 break; 2055 } 2056 2057 genlmsg_end(skb, nlh); 2058 mptcp_nl_mcast_send(net, skb, gfp); 2059 return; 2060 2061 nla_put_failure: 2062 kfree_skb(skb); 2063 } 2064 2065 static const struct genl_small_ops mptcp_pm_ops[] = { 2066 { 2067 .cmd = MPTCP_PM_CMD_ADD_ADDR, 2068 .doit = mptcp_nl_cmd_add_addr, 2069 .flags = GENL_ADMIN_PERM, 2070 }, 2071 { 2072 .cmd = MPTCP_PM_CMD_DEL_ADDR, 2073 .doit = mptcp_nl_cmd_del_addr, 2074 .flags = GENL_ADMIN_PERM, 2075 }, 2076 { 2077 .cmd = MPTCP_PM_CMD_FLUSH_ADDRS, 2078 .doit = mptcp_nl_cmd_flush_addrs, 2079 .flags = GENL_ADMIN_PERM, 2080 }, 2081 { 2082 .cmd = MPTCP_PM_CMD_GET_ADDR, 2083 .doit = mptcp_nl_cmd_get_addr, 2084 .dumpit = mptcp_nl_cmd_dump_addrs, 2085 }, 2086 { 2087 .cmd = MPTCP_PM_CMD_SET_LIMITS, 2088 .doit = mptcp_nl_cmd_set_limits, 2089 .flags = GENL_ADMIN_PERM, 2090 }, 2091 { 2092 .cmd = MPTCP_PM_CMD_GET_LIMITS, 2093 .doit = mptcp_nl_cmd_get_limits, 2094 }, 2095 { 2096 .cmd = MPTCP_PM_CMD_SET_FLAGS, 2097 .doit = mptcp_nl_cmd_set_flags, 2098 .flags = GENL_ADMIN_PERM, 2099 }, 2100 }; 2101 2102 static struct genl_family mptcp_genl_family __ro_after_init = { 2103 .name = MPTCP_PM_NAME, 2104 .version = MPTCP_PM_VER, 2105 .maxattr = MPTCP_PM_ATTR_MAX, 2106 .policy = mptcp_pm_policy, 2107 .netnsok = true, 2108 .module = THIS_MODULE, 2109 .small_ops = mptcp_pm_ops, 2110 .n_small_ops = ARRAY_SIZE(mptcp_pm_ops), 2111 .mcgrps = mptcp_pm_mcgrps, 2112 .n_mcgrps = ARRAY_SIZE(mptcp_pm_mcgrps), 2113 }; 2114 2115 static int __net_init pm_nl_init_net(struct net *net) 2116 { 2117 struct pm_nl_pernet *pernet = net_generic(net, pm_nl_pernet_id); 2118 2119 INIT_LIST_HEAD_RCU(&pernet->local_addr_list); 2120 2121 /* Cit. 2 subflows ought to be enough for anybody. */ 2122 pernet->subflows_max = 2; 2123 pernet->next_id = 1; 2124 pernet->stale_loss_cnt = 4; 2125 spin_lock_init(&pernet->lock); 2126 2127 /* No need to initialize other pernet fields, the struct is zeroed at 2128 * allocation time. 2129 */ 2130 2131 return 0; 2132 } 2133 2134 static void __net_exit pm_nl_exit_net(struct list_head *net_list) 2135 { 2136 struct net *net; 2137 2138 list_for_each_entry(net, net_list, exit_list) { 2139 struct pm_nl_pernet *pernet = net_generic(net, pm_nl_pernet_id); 2140 2141 /* net is removed from namespace list, can't race with 2142 * other modifiers, also netns core already waited for a 2143 * RCU grace period. 2144 */ 2145 __flush_addrs(&pernet->local_addr_list); 2146 } 2147 } 2148 2149 static struct pernet_operations mptcp_pm_pernet_ops = { 2150 .init = pm_nl_init_net, 2151 .exit_batch = pm_nl_exit_net, 2152 .id = &pm_nl_pernet_id, 2153 .size = sizeof(struct pm_nl_pernet), 2154 }; 2155 2156 void __init mptcp_pm_nl_init(void) 2157 { 2158 if (register_pernet_subsys(&mptcp_pm_pernet_ops) < 0) 2159 panic("Failed to register MPTCP PM pernet subsystem.\n"); 2160 2161 if (genl_register_family(&mptcp_genl_family)) 2162 panic("Failed to register MPTCP PM netlink family\n"); 2163 } 2164