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/inet_common.h> 12#include <net/netns/generic.h> 13#include <net/mptcp.h> 14 15#include "protocol.h" 16#include "mib.h" 17 18static int pm_nl_pernet_id; 19 20struct mptcp_pm_add_entry { 21 struct list_head list; 22 struct mptcp_addr_info addr; 23 u8 retrans_times; 24 struct timer_list add_timer; 25 struct mptcp_sock *sock; 26}; 27 28struct pm_nl_pernet { 29 /* protects pernet updates */ 30 spinlock_t lock; 31 struct list_head local_addr_list; 32 unsigned int addrs; 33 unsigned int stale_loss_cnt; 34 unsigned int add_addr_signal_max; 35 unsigned int add_addr_accept_max; 36 unsigned int local_addr_max; 37 unsigned int subflows_max; 38 unsigned int next_id; 39 DECLARE_BITMAP(id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); 40}; 41 42#define MPTCP_PM_ADDR_MAX 8 43#define ADD_ADDR_RETRANS_MAX 3 44 45static struct pm_nl_pernet *pm_nl_get_pernet(const struct net *net) 46{ 47 return net_generic(net, pm_nl_pernet_id); 48} 49 50static struct pm_nl_pernet * 51pm_nl_get_pernet_from_msk(const struct mptcp_sock *msk) 52{ 53 return pm_nl_get_pernet(sock_net((struct sock *)msk)); 54} 55 56bool mptcp_addresses_equal(const struct mptcp_addr_info *a, 57 const struct mptcp_addr_info *b, bool use_port) 58{ 59 bool addr_equals = false; 60 61 if (a->family == b->family) { 62 if (a->family == AF_INET) 63 addr_equals = a->addr.s_addr == b->addr.s_addr; 64#if IS_ENABLED(CONFIG_MPTCP_IPV6) 65 else 66 addr_equals = !ipv6_addr_cmp(&a->addr6, &b->addr6); 67 } else if (a->family == AF_INET) { 68 if (ipv6_addr_v4mapped(&b->addr6)) 69 addr_equals = a->addr.s_addr == b->addr6.s6_addr32[3]; 70 } else if (b->family == AF_INET) { 71 if (ipv6_addr_v4mapped(&a->addr6)) 72 addr_equals = a->addr6.s6_addr32[3] == b->addr.s_addr; 73#endif 74 } 75 76 if (!addr_equals) 77 return false; 78 if (!use_port) 79 return true; 80 81 return a->port == b->port; 82} 83 84void mptcp_local_address(const struct sock_common *skc, struct mptcp_addr_info *addr) 85{ 86 addr->family = skc->skc_family; 87 addr->port = htons(skc->skc_num); 88 if (addr->family == AF_INET) 89 addr->addr.s_addr = skc->skc_rcv_saddr; 90#if IS_ENABLED(CONFIG_MPTCP_IPV6) 91 else if (addr->family == AF_INET6) 92 addr->addr6 = skc->skc_v6_rcv_saddr; 93#endif 94} 95 96static void remote_address(const struct sock_common *skc, 97 struct mptcp_addr_info *addr) 98{ 99 addr->family = skc->skc_family; 100 addr->port = skc->skc_dport; 101 if (addr->family == AF_INET) 102 addr->addr.s_addr = skc->skc_daddr; 103#if IS_ENABLED(CONFIG_MPTCP_IPV6) 104 else if (addr->family == AF_INET6) 105 addr->addr6 = skc->skc_v6_daddr; 106#endif 107} 108 109static bool lookup_subflow_by_saddr(const struct list_head *list, 110 const struct mptcp_addr_info *saddr) 111{ 112 struct mptcp_subflow_context *subflow; 113 struct mptcp_addr_info cur; 114 struct sock_common *skc; 115 116 list_for_each_entry(subflow, list, node) { 117 skc = (struct sock_common *)mptcp_subflow_tcp_sock(subflow); 118 119 mptcp_local_address(skc, &cur); 120 if (mptcp_addresses_equal(&cur, saddr, saddr->port)) 121 return true; 122 } 123 124 return false; 125} 126 127static bool lookup_subflow_by_daddr(const struct list_head *list, 128 const struct mptcp_addr_info *daddr) 129{ 130 struct mptcp_subflow_context *subflow; 131 struct mptcp_addr_info cur; 132 struct sock_common *skc; 133 134 list_for_each_entry(subflow, list, node) { 135 skc = (struct sock_common *)mptcp_subflow_tcp_sock(subflow); 136 137 remote_address(skc, &cur); 138 if (mptcp_addresses_equal(&cur, daddr, daddr->port)) 139 return true; 140 } 141 142 return false; 143} 144 145static struct mptcp_pm_addr_entry * 146select_local_address(const struct pm_nl_pernet *pernet, 147 const struct mptcp_sock *msk) 148{ 149 struct mptcp_pm_addr_entry *entry, *ret = NULL; 150 151 msk_owned_by_me(msk); 152 153 rcu_read_lock(); 154 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 155 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW)) 156 continue; 157 158 if (!test_bit(entry->addr.id, msk->pm.id_avail_bitmap)) 159 continue; 160 161 ret = entry; 162 break; 163 } 164 rcu_read_unlock(); 165 return ret; 166} 167 168static struct mptcp_pm_addr_entry * 169select_signal_address(struct pm_nl_pernet *pernet, const struct mptcp_sock *msk) 170{ 171 struct mptcp_pm_addr_entry *entry, *ret = NULL; 172 173 rcu_read_lock(); 174 /* do not keep any additional per socket state, just signal 175 * the address list in order. 176 * Note: removal from the local address list during the msk life-cycle 177 * can lead to additional addresses not being announced. 178 */ 179 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 180 if (!test_bit(entry->addr.id, msk->pm.id_avail_bitmap)) 181 continue; 182 183 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) 184 continue; 185 186 ret = entry; 187 break; 188 } 189 rcu_read_unlock(); 190 return ret; 191} 192 193unsigned int mptcp_pm_get_add_addr_signal_max(const struct mptcp_sock *msk) 194{ 195 const struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk); 196 197 return READ_ONCE(pernet->add_addr_signal_max); 198} 199EXPORT_SYMBOL_GPL(mptcp_pm_get_add_addr_signal_max); 200 201unsigned int mptcp_pm_get_add_addr_accept_max(const struct mptcp_sock *msk) 202{ 203 struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk); 204 205 return READ_ONCE(pernet->add_addr_accept_max); 206} 207EXPORT_SYMBOL_GPL(mptcp_pm_get_add_addr_accept_max); 208 209unsigned int mptcp_pm_get_subflows_max(const struct mptcp_sock *msk) 210{ 211 struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk); 212 213 return READ_ONCE(pernet->subflows_max); 214} 215EXPORT_SYMBOL_GPL(mptcp_pm_get_subflows_max); 216 217unsigned int mptcp_pm_get_local_addr_max(const struct mptcp_sock *msk) 218{ 219 struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk); 220 221 return READ_ONCE(pernet->local_addr_max); 222} 223EXPORT_SYMBOL_GPL(mptcp_pm_get_local_addr_max); 224 225bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk) 226{ 227 struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk); 228 229 if (msk->pm.subflows == mptcp_pm_get_subflows_max(msk) || 230 (find_next_and_bit(pernet->id_bitmap, msk->pm.id_avail_bitmap, 231 MPTCP_PM_MAX_ADDR_ID + 1, 0) == MPTCP_PM_MAX_ADDR_ID + 1)) { 232 WRITE_ONCE(msk->pm.work_pending, false); 233 return false; 234 } 235 return true; 236} 237 238struct mptcp_pm_add_entry * 239mptcp_lookup_anno_list_by_saddr(const struct mptcp_sock *msk, 240 const struct mptcp_addr_info *addr) 241{ 242 struct mptcp_pm_add_entry *entry; 243 244 lockdep_assert_held(&msk->pm.lock); 245 246 list_for_each_entry(entry, &msk->pm.anno_list, list) { 247 if (mptcp_addresses_equal(&entry->addr, addr, true)) 248 return entry; 249 } 250 251 return NULL; 252} 253 254bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk) 255{ 256 struct mptcp_pm_add_entry *entry; 257 struct mptcp_addr_info saddr; 258 bool ret = false; 259 260 mptcp_local_address((struct sock_common *)sk, &saddr); 261 262 spin_lock_bh(&msk->pm.lock); 263 list_for_each_entry(entry, &msk->pm.anno_list, list) { 264 if (mptcp_addresses_equal(&entry->addr, &saddr, true)) { 265 ret = true; 266 goto out; 267 } 268 } 269 270out: 271 spin_unlock_bh(&msk->pm.lock); 272 return ret; 273} 274 275static void mptcp_pm_add_timer(struct timer_list *timer) 276{ 277 struct mptcp_pm_add_entry *entry = from_timer(entry, timer, add_timer); 278 struct mptcp_sock *msk = entry->sock; 279 struct sock *sk = (struct sock *)msk; 280 281 pr_debug("msk=%p", msk); 282 283 if (!msk) 284 return; 285 286 if (inet_sk_state_load(sk) == TCP_CLOSE) 287 return; 288 289 if (!entry->addr.id) 290 return; 291 292 if (mptcp_pm_should_add_signal_addr(msk)) { 293 sk_reset_timer(sk, timer, jiffies + TCP_RTO_MAX / 8); 294 goto out; 295 } 296 297 spin_lock_bh(&msk->pm.lock); 298 299 if (!mptcp_pm_should_add_signal_addr(msk)) { 300 pr_debug("retransmit ADD_ADDR id=%d", entry->addr.id); 301 mptcp_pm_announce_addr(msk, &entry->addr, false); 302 mptcp_pm_add_addr_send_ack(msk); 303 entry->retrans_times++; 304 } 305 306 if (entry->retrans_times < ADD_ADDR_RETRANS_MAX) 307 sk_reset_timer(sk, timer, 308 jiffies + mptcp_get_add_addr_timeout(sock_net(sk))); 309 310 spin_unlock_bh(&msk->pm.lock); 311 312 if (entry->retrans_times == ADD_ADDR_RETRANS_MAX) 313 mptcp_pm_subflow_established(msk); 314 315out: 316 __sock_put(sk); 317} 318 319struct mptcp_pm_add_entry * 320mptcp_pm_del_add_timer(struct mptcp_sock *msk, 321 const struct mptcp_addr_info *addr, bool check_id) 322{ 323 struct mptcp_pm_add_entry *entry; 324 struct sock *sk = (struct sock *)msk; 325 326 spin_lock_bh(&msk->pm.lock); 327 entry = mptcp_lookup_anno_list_by_saddr(msk, addr); 328 if (entry && (!check_id || entry->addr.id == addr->id)) 329 entry->retrans_times = ADD_ADDR_RETRANS_MAX; 330 spin_unlock_bh(&msk->pm.lock); 331 332 if (entry && (!check_id || entry->addr.id == addr->id)) 333 sk_stop_timer_sync(sk, &entry->add_timer); 334 335 return entry; 336} 337 338bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk, 339 const struct mptcp_addr_info *addr) 340{ 341 struct mptcp_pm_add_entry *add_entry = NULL; 342 struct sock *sk = (struct sock *)msk; 343 struct net *net = sock_net(sk); 344 345 lockdep_assert_held(&msk->pm.lock); 346 347 add_entry = mptcp_lookup_anno_list_by_saddr(msk, addr); 348 349 if (add_entry) { 350 if (mptcp_pm_is_kernel(msk)) 351 return false; 352 353 sk_reset_timer(sk, &add_entry->add_timer, 354 jiffies + mptcp_get_add_addr_timeout(net)); 355 return true; 356 } 357 358 add_entry = kmalloc(sizeof(*add_entry), GFP_ATOMIC); 359 if (!add_entry) 360 return false; 361 362 list_add(&add_entry->list, &msk->pm.anno_list); 363 364 add_entry->addr = *addr; 365 add_entry->sock = msk; 366 add_entry->retrans_times = 0; 367 368 timer_setup(&add_entry->add_timer, mptcp_pm_add_timer, 0); 369 sk_reset_timer(sk, &add_entry->add_timer, 370 jiffies + mptcp_get_add_addr_timeout(net)); 371 372 return true; 373} 374 375void mptcp_pm_free_anno_list(struct mptcp_sock *msk) 376{ 377 struct mptcp_pm_add_entry *entry, *tmp; 378 struct sock *sk = (struct sock *)msk; 379 LIST_HEAD(free_list); 380 381 pr_debug("msk=%p", msk); 382 383 spin_lock_bh(&msk->pm.lock); 384 list_splice_init(&msk->pm.anno_list, &free_list); 385 spin_unlock_bh(&msk->pm.lock); 386 387 list_for_each_entry_safe(entry, tmp, &free_list, list) { 388 sk_stop_timer_sync(sk, &entry->add_timer); 389 kfree(entry); 390 } 391} 392 393/* Fill all the remote addresses into the array addrs[], 394 * and return the array size. 395 */ 396static unsigned int fill_remote_addresses_vec(struct mptcp_sock *msk, 397 struct mptcp_addr_info *local, 398 bool fullmesh, 399 struct mptcp_addr_info *addrs) 400{ 401 bool deny_id0 = READ_ONCE(msk->pm.remote_deny_join_id0); 402 struct sock *sk = (struct sock *)msk, *ssk; 403 struct mptcp_subflow_context *subflow; 404 struct mptcp_addr_info remote = { 0 }; 405 unsigned int subflows_max; 406 int i = 0; 407 408 subflows_max = mptcp_pm_get_subflows_max(msk); 409 remote_address((struct sock_common *)sk, &remote); 410 411 /* Non-fullmesh endpoint, fill in the single entry 412 * corresponding to the primary MPC subflow remote address 413 */ 414 if (!fullmesh) { 415 if (deny_id0) 416 return 0; 417 418 if (!mptcp_pm_addr_families_match(sk, local, &remote)) 419 return 0; 420 421 msk->pm.subflows++; 422 addrs[i++] = remote; 423 } else { 424 DECLARE_BITMAP(unavail_id, MPTCP_PM_MAX_ADDR_ID + 1); 425 426 /* Forbid creation of new subflows matching existing 427 * ones, possibly already created by incoming ADD_ADDR 428 */ 429 bitmap_zero(unavail_id, MPTCP_PM_MAX_ADDR_ID + 1); 430 mptcp_for_each_subflow(msk, subflow) 431 if (READ_ONCE(subflow->local_id) == local->id) 432 __set_bit(subflow->remote_id, unavail_id); 433 434 mptcp_for_each_subflow(msk, subflow) { 435 ssk = mptcp_subflow_tcp_sock(subflow); 436 remote_address((struct sock_common *)ssk, &addrs[i]); 437 addrs[i].id = READ_ONCE(subflow->remote_id); 438 if (deny_id0 && !addrs[i].id) 439 continue; 440 441 if (test_bit(addrs[i].id, unavail_id)) 442 continue; 443 444 if (!mptcp_pm_addr_families_match(sk, local, &addrs[i])) 445 continue; 446 447 if (msk->pm.subflows < subflows_max) { 448 /* forbid creating multiple address towards 449 * this id 450 */ 451 __set_bit(addrs[i].id, unavail_id); 452 msk->pm.subflows++; 453 i++; 454 } 455 } 456 } 457 458 return i; 459} 460 461static void __mptcp_pm_send_ack(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow, 462 bool prio, bool backup) 463{ 464 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 465 bool slow; 466 467 pr_debug("send ack for %s", 468 prio ? "mp_prio" : (mptcp_pm_should_add_signal(msk) ? "add_addr" : "rm_addr")); 469 470 slow = lock_sock_fast(ssk); 471 if (prio) { 472 subflow->send_mp_prio = 1; 473 subflow->backup = backup; 474 subflow->request_bkup = backup; 475 } 476 477 __mptcp_subflow_send_ack(ssk); 478 unlock_sock_fast(ssk, slow); 479} 480 481static void mptcp_pm_send_ack(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow, 482 bool prio, bool backup) 483{ 484 spin_unlock_bh(&msk->pm.lock); 485 __mptcp_pm_send_ack(msk, subflow, prio, backup); 486 spin_lock_bh(&msk->pm.lock); 487} 488 489static struct mptcp_pm_addr_entry * 490__lookup_addr_by_id(struct pm_nl_pernet *pernet, unsigned int id) 491{ 492 struct mptcp_pm_addr_entry *entry; 493 494 list_for_each_entry(entry, &pernet->local_addr_list, list) { 495 if (entry->addr.id == id) 496 return entry; 497 } 498 return NULL; 499} 500 501static struct mptcp_pm_addr_entry * 502__lookup_addr(struct pm_nl_pernet *pernet, const struct mptcp_addr_info *info) 503{ 504 struct mptcp_pm_addr_entry *entry; 505 506 list_for_each_entry(entry, &pernet->local_addr_list, list) { 507 if (mptcp_addresses_equal(&entry->addr, info, entry->addr.port)) 508 return entry; 509 } 510 return NULL; 511} 512 513static void mptcp_pm_create_subflow_or_signal_addr(struct mptcp_sock *msk) 514{ 515 struct sock *sk = (struct sock *)msk; 516 struct mptcp_pm_addr_entry *local; 517 unsigned int add_addr_signal_max; 518 unsigned int local_addr_max; 519 struct pm_nl_pernet *pernet; 520 unsigned int subflows_max; 521 522 pernet = pm_nl_get_pernet(sock_net(sk)); 523 524 add_addr_signal_max = mptcp_pm_get_add_addr_signal_max(msk); 525 local_addr_max = mptcp_pm_get_local_addr_max(msk); 526 subflows_max = mptcp_pm_get_subflows_max(msk); 527 528 /* do lazy endpoint usage accounting for the MPC subflows */ 529 if (unlikely(!(msk->pm.status & BIT(MPTCP_PM_MPC_ENDPOINT_ACCOUNTED))) && msk->first) { 530 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(msk->first); 531 struct mptcp_pm_addr_entry *entry; 532 struct mptcp_addr_info mpc_addr; 533 bool backup = false; 534 535 mptcp_local_address((struct sock_common *)msk->first, &mpc_addr); 536 rcu_read_lock(); 537 entry = __lookup_addr(pernet, &mpc_addr); 538 if (entry) { 539 __clear_bit(entry->addr.id, msk->pm.id_avail_bitmap); 540 msk->mpc_endpoint_id = entry->addr.id; 541 backup = !!(entry->flags & MPTCP_PM_ADDR_FLAG_BACKUP); 542 } 543 rcu_read_unlock(); 544 545 if (backup) 546 mptcp_pm_send_ack(msk, subflow, true, backup); 547 548 msk->pm.status |= BIT(MPTCP_PM_MPC_ENDPOINT_ACCOUNTED); 549 } 550 551 pr_debug("local %d:%d signal %d:%d subflows %d:%d\n", 552 msk->pm.local_addr_used, local_addr_max, 553 msk->pm.add_addr_signaled, add_addr_signal_max, 554 msk->pm.subflows, subflows_max); 555 556 /* check first for announce */ 557 if (msk->pm.add_addr_signaled < add_addr_signal_max) { 558 local = select_signal_address(pernet, msk); 559 560 /* due to racing events on both ends we can reach here while 561 * previous add address is still running: if we invoke now 562 * mptcp_pm_announce_addr(), that will fail and the 563 * corresponding id will be marked as used. 564 * Instead let the PM machinery reschedule us when the 565 * current address announce will be completed. 566 */ 567 if (msk->pm.addr_signal & BIT(MPTCP_ADD_ADDR_SIGNAL)) 568 return; 569 570 if (local) { 571 if (mptcp_pm_alloc_anno_list(msk, &local->addr)) { 572 __clear_bit(local->addr.id, msk->pm.id_avail_bitmap); 573 msk->pm.add_addr_signaled++; 574 mptcp_pm_announce_addr(msk, &local->addr, false); 575 mptcp_pm_nl_addr_send_ack(msk); 576 } 577 } 578 } 579 580 /* check if should create a new subflow */ 581 while (msk->pm.local_addr_used < local_addr_max && 582 msk->pm.subflows < subflows_max) { 583 struct mptcp_addr_info addrs[MPTCP_PM_ADDR_MAX]; 584 bool fullmesh; 585 int i, nr; 586 587 local = select_local_address(pernet, msk); 588 if (!local) 589 break; 590 591 fullmesh = !!(local->flags & MPTCP_PM_ADDR_FLAG_FULLMESH); 592 593 msk->pm.local_addr_used++; 594 __clear_bit(local->addr.id, msk->pm.id_avail_bitmap); 595 nr = fill_remote_addresses_vec(msk, &local->addr, fullmesh, addrs); 596 if (nr == 0) 597 continue; 598 599 spin_unlock_bh(&msk->pm.lock); 600 for (i = 0; i < nr; i++) 601 __mptcp_subflow_connect(sk, &local->addr, &addrs[i]); 602 spin_lock_bh(&msk->pm.lock); 603 } 604 mptcp_pm_nl_check_work_pending(msk); 605} 606 607static void mptcp_pm_nl_fully_established(struct mptcp_sock *msk) 608{ 609 mptcp_pm_create_subflow_or_signal_addr(msk); 610} 611 612static void mptcp_pm_nl_subflow_established(struct mptcp_sock *msk) 613{ 614 mptcp_pm_create_subflow_or_signal_addr(msk); 615} 616 617/* Fill all the local addresses into the array addrs[], 618 * and return the array size. 619 */ 620static unsigned int fill_local_addresses_vec(struct mptcp_sock *msk, 621 struct mptcp_addr_info *remote, 622 struct mptcp_addr_info *addrs) 623{ 624 struct sock *sk = (struct sock *)msk; 625 struct mptcp_pm_addr_entry *entry; 626 struct pm_nl_pernet *pernet; 627 unsigned int subflows_max; 628 int i = 0; 629 630 pernet = pm_nl_get_pernet_from_msk(msk); 631 subflows_max = mptcp_pm_get_subflows_max(msk); 632 633 rcu_read_lock(); 634 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 635 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_FULLMESH)) 636 continue; 637 638 if (!mptcp_pm_addr_families_match(sk, &entry->addr, remote)) 639 continue; 640 641 if (msk->pm.subflows < subflows_max) { 642 msk->pm.subflows++; 643 addrs[i++] = entry->addr; 644 } 645 } 646 rcu_read_unlock(); 647 648 /* If the array is empty, fill in the single 649 * 'IPADDRANY' local address 650 */ 651 if (!i) { 652 struct mptcp_addr_info local; 653 654 memset(&local, 0, sizeof(local)); 655 local.family = 656#if IS_ENABLED(CONFIG_MPTCP_IPV6) 657 remote->family == AF_INET6 && 658 ipv6_addr_v4mapped(&remote->addr6) ? AF_INET : 659#endif 660 remote->family; 661 662 if (!mptcp_pm_addr_families_match(sk, &local, remote)) 663 return 0; 664 665 msk->pm.subflows++; 666 addrs[i++] = local; 667 } 668 669 return i; 670} 671 672static void mptcp_pm_nl_add_addr_received(struct mptcp_sock *msk) 673{ 674 struct mptcp_addr_info addrs[MPTCP_PM_ADDR_MAX]; 675 struct sock *sk = (struct sock *)msk; 676 unsigned int add_addr_accept_max; 677 struct mptcp_addr_info remote; 678 unsigned int subflows_max; 679 int i, nr; 680 681 add_addr_accept_max = mptcp_pm_get_add_addr_accept_max(msk); 682 subflows_max = mptcp_pm_get_subflows_max(msk); 683 684 pr_debug("accepted %d:%d remote family %d", 685 msk->pm.add_addr_accepted, add_addr_accept_max, 686 msk->pm.remote.family); 687 688 remote = msk->pm.remote; 689 mptcp_pm_announce_addr(msk, &remote, true); 690 mptcp_pm_nl_addr_send_ack(msk); 691 692 if (lookup_subflow_by_daddr(&msk->conn_list, &remote)) 693 return; 694 695 /* pick id 0 port, if none is provided the remote address */ 696 if (!remote.port) 697 remote.port = sk->sk_dport; 698 699 /* connect to the specified remote address, using whatever 700 * local address the routing configuration will pick. 701 */ 702 nr = fill_local_addresses_vec(msk, &remote, addrs); 703 if (nr == 0) 704 return; 705 706 msk->pm.add_addr_accepted++; 707 if (msk->pm.add_addr_accepted >= add_addr_accept_max || 708 msk->pm.subflows >= subflows_max) 709 WRITE_ONCE(msk->pm.accept_addr, false); 710 711 spin_unlock_bh(&msk->pm.lock); 712 for (i = 0; i < nr; i++) 713 __mptcp_subflow_connect(sk, &addrs[i], &remote); 714 spin_lock_bh(&msk->pm.lock); 715} 716 717void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk) 718{ 719 struct mptcp_subflow_context *subflow; 720 721 msk_owned_by_me(msk); 722 lockdep_assert_held(&msk->pm.lock); 723 724 if (!mptcp_pm_should_add_signal(msk) && 725 !mptcp_pm_should_rm_signal(msk)) 726 return; 727 728 subflow = list_first_entry_or_null(&msk->conn_list, typeof(*subflow), node); 729 if (subflow) 730 mptcp_pm_send_ack(msk, subflow, false, false); 731} 732 733int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk, 734 struct mptcp_addr_info *addr, 735 struct mptcp_addr_info *rem, 736 u8 bkup) 737{ 738 struct mptcp_subflow_context *subflow; 739 740 pr_debug("bkup=%d", bkup); 741 742 mptcp_for_each_subflow(msk, subflow) { 743 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 744 struct mptcp_addr_info local, remote; 745 746 mptcp_local_address((struct sock_common *)ssk, &local); 747 if (!mptcp_addresses_equal(&local, addr, addr->port)) 748 continue; 749 750 if (rem && rem->family != AF_UNSPEC) { 751 remote_address((struct sock_common *)ssk, &remote); 752 if (!mptcp_addresses_equal(&remote, rem, rem->port)) 753 continue; 754 } 755 756 __mptcp_pm_send_ack(msk, subflow, true, bkup); 757 return 0; 758 } 759 760 return -EINVAL; 761} 762 763static bool mptcp_local_id_match(const struct mptcp_sock *msk, u8 local_id, u8 id) 764{ 765 return local_id == id || (!local_id && msk->mpc_endpoint_id == id); 766} 767 768static void mptcp_pm_nl_rm_addr_or_subflow(struct mptcp_sock *msk, 769 const struct mptcp_rm_list *rm_list, 770 enum linux_mptcp_mib_field rm_type) 771{ 772 struct mptcp_subflow_context *subflow, *tmp; 773 struct sock *sk = (struct sock *)msk; 774 u8 i; 775 776 pr_debug("%s rm_list_nr %d", 777 rm_type == MPTCP_MIB_RMADDR ? "address" : "subflow", rm_list->nr); 778 779 msk_owned_by_me(msk); 780 781 if (sk->sk_state == TCP_LISTEN) 782 return; 783 784 if (!rm_list->nr) 785 return; 786 787 if (list_empty(&msk->conn_list)) 788 return; 789 790 for (i = 0; i < rm_list->nr; i++) { 791 u8 rm_id = rm_list->ids[i]; 792 bool removed = false; 793 794 mptcp_for_each_subflow_safe(msk, subflow, tmp) { 795 struct sock *ssk = mptcp_subflow_tcp_sock(subflow); 796 u8 remote_id = READ_ONCE(subflow->remote_id); 797 int how = RCV_SHUTDOWN | SEND_SHUTDOWN; 798 u8 id = subflow_get_local_id(subflow); 799 800 if (rm_type == MPTCP_MIB_RMADDR && remote_id != rm_id) 801 continue; 802 if (rm_type == MPTCP_MIB_RMSUBFLOW && !mptcp_local_id_match(msk, id, rm_id)) 803 continue; 804 805 pr_debug(" -> %s rm_list_ids[%d]=%u local_id=%u remote_id=%u mpc_id=%u", 806 rm_type == MPTCP_MIB_RMADDR ? "address" : "subflow", 807 i, rm_id, id, remote_id, msk->mpc_endpoint_id); 808 spin_unlock_bh(&msk->pm.lock); 809 mptcp_subflow_shutdown(sk, ssk, how); 810 811 /* the following takes care of updating the subflows counter */ 812 mptcp_close_ssk(sk, ssk, subflow); 813 spin_lock_bh(&msk->pm.lock); 814 815 removed = true; 816 __MPTCP_INC_STATS(sock_net(sk), rm_type); 817 } 818 if (rm_type == MPTCP_MIB_RMSUBFLOW) 819 __set_bit(rm_id ? rm_id : msk->mpc_endpoint_id, msk->pm.id_avail_bitmap); 820 if (!removed) 821 continue; 822 823 if (!mptcp_pm_is_kernel(msk)) 824 continue; 825 826 if (rm_type == MPTCP_MIB_RMADDR) { 827 msk->pm.add_addr_accepted--; 828 WRITE_ONCE(msk->pm.accept_addr, true); 829 } else if (rm_type == MPTCP_MIB_RMSUBFLOW) { 830 msk->pm.local_addr_used--; 831 } 832 } 833} 834 835static void mptcp_pm_nl_rm_addr_received(struct mptcp_sock *msk) 836{ 837 mptcp_pm_nl_rm_addr_or_subflow(msk, &msk->pm.rm_list_rx, MPTCP_MIB_RMADDR); 838} 839 840void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk, 841 const struct mptcp_rm_list *rm_list) 842{ 843 mptcp_pm_nl_rm_addr_or_subflow(msk, rm_list, MPTCP_MIB_RMSUBFLOW); 844} 845 846void mptcp_pm_nl_work(struct mptcp_sock *msk) 847{ 848 struct mptcp_pm_data *pm = &msk->pm; 849 850 msk_owned_by_me(msk); 851 852 if (!(pm->status & MPTCP_PM_WORK_MASK)) 853 return; 854 855 spin_lock_bh(&msk->pm.lock); 856 857 pr_debug("msk=%p status=%x", msk, pm->status); 858 if (pm->status & BIT(MPTCP_PM_ADD_ADDR_RECEIVED)) { 859 pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_RECEIVED); 860 mptcp_pm_nl_add_addr_received(msk); 861 } 862 if (pm->status & BIT(MPTCP_PM_ADD_ADDR_SEND_ACK)) { 863 pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_SEND_ACK); 864 mptcp_pm_nl_addr_send_ack(msk); 865 } 866 if (pm->status & BIT(MPTCP_PM_RM_ADDR_RECEIVED)) { 867 pm->status &= ~BIT(MPTCP_PM_RM_ADDR_RECEIVED); 868 mptcp_pm_nl_rm_addr_received(msk); 869 } 870 if (pm->status & BIT(MPTCP_PM_ESTABLISHED)) { 871 pm->status &= ~BIT(MPTCP_PM_ESTABLISHED); 872 mptcp_pm_nl_fully_established(msk); 873 } 874 if (pm->status & BIT(MPTCP_PM_SUBFLOW_ESTABLISHED)) { 875 pm->status &= ~BIT(MPTCP_PM_SUBFLOW_ESTABLISHED); 876 mptcp_pm_nl_subflow_established(msk); 877 } 878 879 spin_unlock_bh(&msk->pm.lock); 880} 881 882static bool address_use_port(struct mptcp_pm_addr_entry *entry) 883{ 884 return (entry->flags & 885 (MPTCP_PM_ADDR_FLAG_SIGNAL | MPTCP_PM_ADDR_FLAG_SUBFLOW)) == 886 MPTCP_PM_ADDR_FLAG_SIGNAL; 887} 888 889/* caller must ensure the RCU grace period is already elapsed */ 890static void __mptcp_pm_release_addr_entry(struct mptcp_pm_addr_entry *entry) 891{ 892 if (entry->lsk) 893 sock_release(entry->lsk); 894 kfree(entry); 895} 896 897static int mptcp_pm_nl_append_new_local_addr(struct pm_nl_pernet *pernet, 898 struct mptcp_pm_addr_entry *entry, 899 bool needs_id) 900{ 901 struct mptcp_pm_addr_entry *cur, *del_entry = NULL; 902 unsigned int addr_max; 903 int ret = -EINVAL; 904 905 spin_lock_bh(&pernet->lock); 906 /* to keep the code simple, don't do IDR-like allocation for address ID, 907 * just bail when we exceed limits 908 */ 909 if (pernet->next_id == MPTCP_PM_MAX_ADDR_ID) 910 pernet->next_id = 1; 911 if (pernet->addrs >= MPTCP_PM_ADDR_MAX) { 912 ret = -ERANGE; 913 goto out; 914 } 915 if (test_bit(entry->addr.id, pernet->id_bitmap)) { 916 ret = -EBUSY; 917 goto out; 918 } 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 ret = -EEXIST; 934 goto out; 935 } 936 if (entry->addr.id) 937 goto out; 938 939 pernet->addrs--; 940 entry->addr.id = cur->addr.id; 941 list_del_rcu(&cur->list); 942 del_entry = cur; 943 break; 944 } 945 } 946 947 if (!entry->addr.id && needs_id) { 948find_next: 949 entry->addr.id = find_next_zero_bit(pernet->id_bitmap, 950 MPTCP_PM_MAX_ADDR_ID + 1, 951 pernet->next_id); 952 if (!entry->addr.id && pernet->next_id != 1) { 953 pernet->next_id = 1; 954 goto find_next; 955 } 956 } 957 958 if (!entry->addr.id && needs_id) 959 goto out; 960 961 __set_bit(entry->addr.id, pernet->id_bitmap); 962 if (entry->addr.id > pernet->next_id) 963 pernet->next_id = entry->addr.id; 964 965 if (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL) { 966 addr_max = pernet->add_addr_signal_max; 967 WRITE_ONCE(pernet->add_addr_signal_max, addr_max + 1); 968 } 969 if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) { 970 addr_max = pernet->local_addr_max; 971 WRITE_ONCE(pernet->local_addr_max, addr_max + 1); 972 } 973 974 pernet->addrs++; 975 if (!entry->addr.port) 976 list_add_tail_rcu(&entry->list, &pernet->local_addr_list); 977 else 978 list_add_rcu(&entry->list, &pernet->local_addr_list); 979 ret = entry->addr.id; 980 981out: 982 spin_unlock_bh(&pernet->lock); 983 984 /* just replaced an existing entry, free it */ 985 if (del_entry) { 986 synchronize_rcu(); 987 __mptcp_pm_release_addr_entry(del_entry); 988 } 989 return ret; 990} 991 992static struct lock_class_key mptcp_slock_keys[2]; 993static struct lock_class_key mptcp_keys[2]; 994 995static int mptcp_pm_nl_create_listen_socket(struct sock *sk, 996 struct mptcp_pm_addr_entry *entry) 997{ 998 bool is_ipv6 = sk->sk_family == AF_INET6; 999 int addrlen = sizeof(struct sockaddr_in); 1000 struct sockaddr_storage addr; 1001 struct sock *newsk, *ssk; 1002 int backlog = 1024; 1003 int err; 1004 1005 err = sock_create_kern(sock_net(sk), entry->addr.family, 1006 SOCK_STREAM, IPPROTO_MPTCP, &entry->lsk); 1007 if (err) 1008 return err; 1009 1010 newsk = entry->lsk->sk; 1011 if (!newsk) 1012 return -EINVAL; 1013 1014 /* The subflow socket lock is acquired in a nested to the msk one 1015 * in several places, even by the TCP stack, and this msk is a kernel 1016 * socket: lockdep complains. Instead of propagating the _nested 1017 * modifiers in several places, re-init the lock class for the msk 1018 * socket to an mptcp specific one. 1019 */ 1020 sock_lock_init_class_and_name(newsk, 1021 is_ipv6 ? "mlock-AF_INET6" : "mlock-AF_INET", 1022 &mptcp_slock_keys[is_ipv6], 1023 is_ipv6 ? "msk_lock-AF_INET6" : "msk_lock-AF_INET", 1024 &mptcp_keys[is_ipv6]); 1025 1026 lock_sock(newsk); 1027 ssk = __mptcp_nmpc_sk(mptcp_sk(newsk)); 1028 release_sock(newsk); 1029 if (IS_ERR(ssk)) 1030 return PTR_ERR(ssk); 1031 1032 mptcp_info2sockaddr(&entry->addr, &addr, entry->addr.family); 1033#if IS_ENABLED(CONFIG_MPTCP_IPV6) 1034 if (entry->addr.family == AF_INET6) 1035 addrlen = sizeof(struct sockaddr_in6); 1036#endif 1037 if (ssk->sk_family == AF_INET) 1038 err = inet_bind_sk(ssk, (struct sockaddr *)&addr, addrlen); 1039#if IS_ENABLED(CONFIG_MPTCP_IPV6) 1040 else if (ssk->sk_family == AF_INET6) 1041 err = inet6_bind_sk(ssk, (struct sockaddr *)&addr, addrlen); 1042#endif 1043 if (err) 1044 return err; 1045 1046 /* We don't use mptcp_set_state() here because it needs to be called 1047 * under the msk socket lock. For the moment, that will not bring 1048 * anything more than only calling inet_sk_state_store(), because the 1049 * old status is known (TCP_CLOSE). 1050 */ 1051 inet_sk_state_store(newsk, TCP_LISTEN); 1052 lock_sock(ssk); 1053 err = __inet_listen_sk(ssk, backlog); 1054 if (!err) 1055 mptcp_event_pm_listener(ssk, MPTCP_EVENT_LISTENER_CREATED); 1056 release_sock(ssk); 1057 return err; 1058} 1059 1060int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc) 1061{ 1062 struct mptcp_pm_addr_entry *entry; 1063 struct pm_nl_pernet *pernet; 1064 int ret = -1; 1065 1066 pernet = pm_nl_get_pernet_from_msk(msk); 1067 1068 rcu_read_lock(); 1069 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) { 1070 if (mptcp_addresses_equal(&entry->addr, skc, entry->addr.port)) { 1071 ret = entry->addr.id; 1072 break; 1073 } 1074 } 1075 rcu_read_unlock(); 1076 if (ret >= 0) 1077 return ret; 1078 1079 /* address not found, add to local list */ 1080 entry = kmalloc(sizeof(*entry), GFP_ATOMIC); 1081 if (!entry) 1082 return -ENOMEM; 1083 1084 entry->addr = *skc; 1085 entry->addr.id = 0; 1086 entry->addr.port = 0; 1087 entry->ifindex = 0; 1088 entry->flags = MPTCP_PM_ADDR_FLAG_IMPLICIT; 1089 entry->lsk = NULL; 1090 ret = mptcp_pm_nl_append_new_local_addr(pernet, entry, true); 1091 if (ret < 0) 1092 kfree(entry); 1093 1094 return ret; 1095} 1096 1097#define MPTCP_PM_CMD_GRP_OFFSET 0 1098#define MPTCP_PM_EV_GRP_OFFSET 1 1099 1100static const struct genl_multicast_group mptcp_pm_mcgrps[] = { 1101 [MPTCP_PM_CMD_GRP_OFFSET] = { .name = MPTCP_PM_CMD_GRP_NAME, }, 1102 [MPTCP_PM_EV_GRP_OFFSET] = { .name = MPTCP_PM_EV_GRP_NAME, 1103 .flags = GENL_MCAST_CAP_NET_ADMIN, 1104 }, 1105}; 1106 1107void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk) 1108{ 1109 struct mptcp_subflow_context *iter, *subflow = mptcp_subflow_ctx(ssk); 1110 struct sock *sk = (struct sock *)msk; 1111 unsigned int active_max_loss_cnt; 1112 struct net *net = sock_net(sk); 1113 unsigned int stale_loss_cnt; 1114 bool slow; 1115 1116 stale_loss_cnt = mptcp_stale_loss_cnt(net); 1117 if (subflow->stale || !stale_loss_cnt || subflow->stale_count <= stale_loss_cnt) 1118 return; 1119 1120 /* look for another available subflow not in loss state */ 1121 active_max_loss_cnt = max_t(int, stale_loss_cnt - 1, 1); 1122 mptcp_for_each_subflow(msk, iter) { 1123 if (iter != subflow && mptcp_subflow_active(iter) && 1124 iter->stale_count < active_max_loss_cnt) { 1125 /* we have some alternatives, try to mark this subflow as idle ...*/ 1126 slow = lock_sock_fast(ssk); 1127 if (!tcp_rtx_and_write_queues_empty(ssk)) { 1128 subflow->stale = 1; 1129 __mptcp_retransmit_pending_data(sk); 1130 MPTCP_INC_STATS(net, MPTCP_MIB_SUBFLOWSTALE); 1131 } 1132 unlock_sock_fast(ssk, slow); 1133 1134 /* always try to push the pending data regardless of re-injections: 1135 * we can possibly use backup subflows now, and subflow selection 1136 * is cheap under the msk socket lock 1137 */ 1138 __mptcp_push_pending(sk, 0); 1139 return; 1140 } 1141 } 1142} 1143 1144static int mptcp_pm_family_to_addr(int family) 1145{ 1146#if IS_ENABLED(CONFIG_MPTCP_IPV6) 1147 if (family == AF_INET6) 1148 return MPTCP_PM_ADDR_ATTR_ADDR6; 1149#endif 1150 return MPTCP_PM_ADDR_ATTR_ADDR4; 1151} 1152 1153static int mptcp_pm_parse_pm_addr_attr(struct nlattr *tb[], 1154 const struct nlattr *attr, 1155 struct genl_info *info, 1156 struct mptcp_addr_info *addr, 1157 bool require_family) 1158{ 1159 int err, addr_addr; 1160 1161 if (!attr) { 1162 GENL_SET_ERR_MSG(info, "missing address info"); 1163 return -EINVAL; 1164 } 1165 1166 /* no validation needed - was already done via nested policy */ 1167 err = nla_parse_nested_deprecated(tb, MPTCP_PM_ADDR_ATTR_MAX, attr, 1168 mptcp_pm_address_nl_policy, info->extack); 1169 if (err) 1170 return err; 1171 1172 if (tb[MPTCP_PM_ADDR_ATTR_ID]) 1173 addr->id = nla_get_u8(tb[MPTCP_PM_ADDR_ATTR_ID]); 1174 1175 if (!tb[MPTCP_PM_ADDR_ATTR_FAMILY]) { 1176 if (!require_family) 1177 return 0; 1178 1179 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1180 "missing family"); 1181 return -EINVAL; 1182 } 1183 1184 addr->family = nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_FAMILY]); 1185 if (addr->family != AF_INET 1186#if IS_ENABLED(CONFIG_MPTCP_IPV6) 1187 && addr->family != AF_INET6 1188#endif 1189 ) { 1190 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1191 "unknown address family"); 1192 return -EINVAL; 1193 } 1194 addr_addr = mptcp_pm_family_to_addr(addr->family); 1195 if (!tb[addr_addr]) { 1196 NL_SET_ERR_MSG_ATTR(info->extack, attr, 1197 "missing address data"); 1198 return -EINVAL; 1199 } 1200 1201#if IS_ENABLED(CONFIG_MPTCP_IPV6) 1202 if (addr->family == AF_INET6) 1203 addr->addr6 = nla_get_in6_addr(tb[addr_addr]); 1204 else 1205#endif 1206 addr->addr.s_addr = nla_get_in_addr(tb[addr_addr]); 1207 1208 if (tb[MPTCP_PM_ADDR_ATTR_PORT]) 1209 addr->port = htons(nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_PORT])); 1210 1211 return 0; 1212} 1213 1214int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info, 1215 struct mptcp_addr_info *addr) 1216{ 1217 struct nlattr *tb[MPTCP_PM_ADDR_ATTR_MAX + 1]; 1218 1219 memset(addr, 0, sizeof(*addr)); 1220 1221 return mptcp_pm_parse_pm_addr_attr(tb, attr, info, addr, true); 1222} 1223 1224int mptcp_pm_parse_entry(struct nlattr *attr, struct genl_info *info, 1225 bool require_family, 1226 struct mptcp_pm_addr_entry *entry) 1227{ 1228 struct nlattr *tb[MPTCP_PM_ADDR_ATTR_MAX + 1]; 1229 int err; 1230 1231 memset(entry, 0, sizeof(*entry)); 1232 1233 err = mptcp_pm_parse_pm_addr_attr(tb, attr, info, &entry->addr, require_family); 1234 if (err) 1235 return err; 1236 1237 if (tb[MPTCP_PM_ADDR_ATTR_IF_IDX]) { 1238 u32 val = nla_get_s32(tb[MPTCP_PM_ADDR_ATTR_IF_IDX]); 1239 1240 entry->ifindex = val; 1241 } 1242 1243 if (tb[MPTCP_PM_ADDR_ATTR_FLAGS]) 1244 entry->flags = nla_get_u32(tb[MPTCP_PM_ADDR_ATTR_FLAGS]); 1245 1246 if (tb[MPTCP_PM_ADDR_ATTR_PORT]) 1247 entry->addr.port = htons(nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_PORT])); 1248 1249 return 0; 1250} 1251 1252static struct pm_nl_pernet *genl_info_pm_nl(struct genl_info *info) 1253{ 1254 return pm_nl_get_pernet(genl_info_net(info)); 1255} 1256 1257static int mptcp_nl_add_subflow_or_signal_addr(struct net *net) 1258{ 1259 struct mptcp_sock *msk; 1260 long s_slot = 0, s_num = 0; 1261 1262 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1263 struct sock *sk = (struct sock *)msk; 1264 1265 if (!READ_ONCE(msk->fully_established) || 1266 mptcp_pm_is_userspace(msk)) 1267 goto next; 1268 1269 lock_sock(sk); 1270 spin_lock_bh(&msk->pm.lock); 1271 mptcp_pm_create_subflow_or_signal_addr(msk); 1272 spin_unlock_bh(&msk->pm.lock); 1273 release_sock(sk); 1274 1275next: 1276 sock_put(sk); 1277 cond_resched(); 1278 } 1279 1280 return 0; 1281} 1282 1283static bool mptcp_pm_has_addr_attr_id(const struct nlattr *attr, 1284 struct genl_info *info) 1285{ 1286 struct nlattr *tb[MPTCP_PM_ADDR_ATTR_MAX + 1]; 1287 1288 if (!nla_parse_nested_deprecated(tb, MPTCP_PM_ADDR_ATTR_MAX, attr, 1289 mptcp_pm_address_nl_policy, info->extack) && 1290 tb[MPTCP_PM_ADDR_ATTR_ID]) 1291 return true; 1292 return false; 1293} 1294 1295int mptcp_pm_nl_add_addr_doit(struct sk_buff *skb, struct genl_info *info) 1296{ 1297 struct nlattr *attr = info->attrs[MPTCP_PM_ENDPOINT_ADDR]; 1298 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1299 struct mptcp_pm_addr_entry addr, *entry; 1300 int ret; 1301 1302 ret = mptcp_pm_parse_entry(attr, info, true, &addr); 1303 if (ret < 0) 1304 return ret; 1305 1306 if (addr.addr.port && !(addr.flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) { 1307 GENL_SET_ERR_MSG(info, "flags must have signal when using port"); 1308 return -EINVAL; 1309 } 1310 1311 if (addr.flags & MPTCP_PM_ADDR_FLAG_SIGNAL && 1312 addr.flags & MPTCP_PM_ADDR_FLAG_FULLMESH) { 1313 GENL_SET_ERR_MSG(info, "flags mustn't have both signal and fullmesh"); 1314 return -EINVAL; 1315 } 1316 1317 if (addr.flags & MPTCP_PM_ADDR_FLAG_IMPLICIT) { 1318 GENL_SET_ERR_MSG(info, "can't create IMPLICIT endpoint"); 1319 return -EINVAL; 1320 } 1321 1322 entry = kzalloc(sizeof(*entry), GFP_KERNEL_ACCOUNT); 1323 if (!entry) { 1324 GENL_SET_ERR_MSG(info, "can't allocate addr"); 1325 return -ENOMEM; 1326 } 1327 1328 *entry = addr; 1329 if (entry->addr.port) { 1330 ret = mptcp_pm_nl_create_listen_socket(skb->sk, entry); 1331 if (ret) { 1332 GENL_SET_ERR_MSG_FMT(info, "create listen socket error: %d", ret); 1333 goto out_free; 1334 } 1335 } 1336 ret = mptcp_pm_nl_append_new_local_addr(pernet, entry, 1337 !mptcp_pm_has_addr_attr_id(attr, info)); 1338 if (ret < 0) { 1339 GENL_SET_ERR_MSG_FMT(info, "too many addresses or duplicate one: %d", ret); 1340 goto out_free; 1341 } 1342 1343 mptcp_nl_add_subflow_or_signal_addr(sock_net(skb->sk)); 1344 return 0; 1345 1346out_free: 1347 __mptcp_pm_release_addr_entry(entry); 1348 return ret; 1349} 1350 1351int mptcp_pm_nl_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, unsigned int id, 1352 u8 *flags, int *ifindex) 1353{ 1354 struct mptcp_pm_addr_entry *entry; 1355 struct sock *sk = (struct sock *)msk; 1356 struct net *net = sock_net(sk); 1357 1358 rcu_read_lock(); 1359 entry = __lookup_addr_by_id(pm_nl_get_pernet(net), id); 1360 if (entry) { 1361 *flags = entry->flags; 1362 *ifindex = entry->ifindex; 1363 } 1364 rcu_read_unlock(); 1365 1366 return 0; 1367} 1368 1369static bool remove_anno_list_by_saddr(struct mptcp_sock *msk, 1370 const struct mptcp_addr_info *addr) 1371{ 1372 struct mptcp_pm_add_entry *entry; 1373 1374 entry = mptcp_pm_del_add_timer(msk, addr, false); 1375 if (entry) { 1376 list_del(&entry->list); 1377 kfree(entry); 1378 return true; 1379 } 1380 1381 return false; 1382} 1383 1384static bool mptcp_pm_remove_anno_addr(struct mptcp_sock *msk, 1385 const struct mptcp_addr_info *addr, 1386 bool force) 1387{ 1388 struct mptcp_rm_list list = { .nr = 0 }; 1389 bool ret; 1390 1391 list.ids[list.nr++] = addr->id; 1392 1393 ret = remove_anno_list_by_saddr(msk, addr); 1394 if (ret || force) { 1395 spin_lock_bh(&msk->pm.lock); 1396 mptcp_pm_remove_addr(msk, &list); 1397 spin_unlock_bh(&msk->pm.lock); 1398 } 1399 return ret; 1400} 1401 1402static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net, 1403 const struct mptcp_pm_addr_entry *entry) 1404{ 1405 const struct mptcp_addr_info *addr = &entry->addr; 1406 struct mptcp_rm_list list = { .nr = 0 }; 1407 long s_slot = 0, s_num = 0; 1408 struct mptcp_sock *msk; 1409 1410 pr_debug("remove_id=%d", addr->id); 1411 1412 list.ids[list.nr++] = addr->id; 1413 1414 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1415 struct sock *sk = (struct sock *)msk; 1416 bool remove_subflow; 1417 1418 if (mptcp_pm_is_userspace(msk)) 1419 goto next; 1420 1421 if (list_empty(&msk->conn_list)) { 1422 mptcp_pm_remove_anno_addr(msk, addr, false); 1423 goto next; 1424 } 1425 1426 lock_sock(sk); 1427 remove_subflow = lookup_subflow_by_saddr(&msk->conn_list, addr); 1428 mptcp_pm_remove_anno_addr(msk, addr, remove_subflow && 1429 !(entry->flags & MPTCP_PM_ADDR_FLAG_IMPLICIT)); 1430 if (remove_subflow) 1431 mptcp_pm_remove_subflow(msk, &list); 1432 release_sock(sk); 1433 1434next: 1435 sock_put(sk); 1436 cond_resched(); 1437 } 1438 1439 return 0; 1440} 1441 1442static int mptcp_nl_remove_id_zero_address(struct net *net, 1443 struct mptcp_addr_info *addr) 1444{ 1445 struct mptcp_rm_list list = { .nr = 0 }; 1446 long s_slot = 0, s_num = 0; 1447 struct mptcp_sock *msk; 1448 1449 list.ids[list.nr++] = 0; 1450 1451 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1452 struct sock *sk = (struct sock *)msk; 1453 struct mptcp_addr_info msk_local; 1454 1455 if (list_empty(&msk->conn_list) || mptcp_pm_is_userspace(msk)) 1456 goto next; 1457 1458 mptcp_local_address((struct sock_common *)msk, &msk_local); 1459 if (!mptcp_addresses_equal(&msk_local, addr, addr->port)) 1460 goto next; 1461 1462 lock_sock(sk); 1463 spin_lock_bh(&msk->pm.lock); 1464 mptcp_pm_remove_addr(msk, &list); 1465 mptcp_pm_nl_rm_subflow_received(msk, &list); 1466 spin_unlock_bh(&msk->pm.lock); 1467 release_sock(sk); 1468 1469next: 1470 sock_put(sk); 1471 cond_resched(); 1472 } 1473 1474 return 0; 1475} 1476 1477int mptcp_pm_nl_del_addr_doit(struct sk_buff *skb, struct genl_info *info) 1478{ 1479 struct nlattr *attr = info->attrs[MPTCP_PM_ENDPOINT_ADDR]; 1480 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1481 struct mptcp_pm_addr_entry addr, *entry; 1482 unsigned int addr_max; 1483 int ret; 1484 1485 ret = mptcp_pm_parse_entry(attr, info, false, &addr); 1486 if (ret < 0) 1487 return ret; 1488 1489 /* the zero id address is special: the first address used by the msk 1490 * always gets such an id, so different subflows can have different zero 1491 * id addresses. Additionally zero id is not accounted for in id_bitmap. 1492 * Let's use an 'mptcp_rm_list' instead of the common remove code. 1493 */ 1494 if (addr.addr.id == 0) 1495 return mptcp_nl_remove_id_zero_address(sock_net(skb->sk), &addr.addr); 1496 1497 spin_lock_bh(&pernet->lock); 1498 entry = __lookup_addr_by_id(pernet, addr.addr.id); 1499 if (!entry) { 1500 GENL_SET_ERR_MSG(info, "address not found"); 1501 spin_unlock_bh(&pernet->lock); 1502 return -EINVAL; 1503 } 1504 if (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL) { 1505 addr_max = pernet->add_addr_signal_max; 1506 WRITE_ONCE(pernet->add_addr_signal_max, addr_max - 1); 1507 } 1508 if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) { 1509 addr_max = pernet->local_addr_max; 1510 WRITE_ONCE(pernet->local_addr_max, addr_max - 1); 1511 } 1512 1513 pernet->addrs--; 1514 list_del_rcu(&entry->list); 1515 __clear_bit(entry->addr.id, pernet->id_bitmap); 1516 spin_unlock_bh(&pernet->lock); 1517 1518 mptcp_nl_remove_subflow_and_signal_addr(sock_net(skb->sk), entry); 1519 synchronize_rcu(); 1520 __mptcp_pm_release_addr_entry(entry); 1521 1522 return ret; 1523} 1524 1525void mptcp_pm_remove_addrs(struct mptcp_sock *msk, struct list_head *rm_list) 1526{ 1527 struct mptcp_rm_list alist = { .nr = 0 }; 1528 struct mptcp_pm_addr_entry *entry; 1529 1530 list_for_each_entry(entry, rm_list, list) { 1531 if ((remove_anno_list_by_saddr(msk, &entry->addr) || 1532 lookup_subflow_by_saddr(&msk->conn_list, &entry->addr)) && 1533 alist.nr < MPTCP_RM_IDS_MAX) 1534 alist.ids[alist.nr++] = entry->addr.id; 1535 } 1536 1537 if (alist.nr) { 1538 spin_lock_bh(&msk->pm.lock); 1539 mptcp_pm_remove_addr(msk, &alist); 1540 spin_unlock_bh(&msk->pm.lock); 1541 } 1542} 1543 1544static 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 1569static 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 */ 1593static 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 1605static 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 1613int mptcp_pm_nl_flush_addrs_doit(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 1630int 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 1664nla_put_failure: 1665 nla_nest_cancel(skb, attr); 1666 return -EMSGSIZE; 1667} 1668 1669int mptcp_pm_nl_get_addr(struct sk_buff *skb, struct genl_info *info) 1670{ 1671 struct nlattr *attr = info->attrs[MPTCP_PM_ENDPOINT_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 1711unlock_fail: 1712 spin_unlock_bh(&pernet->lock); 1713 1714fail: 1715 nlmsg_free(msg); 1716 return ret; 1717} 1718 1719int mptcp_pm_nl_get_addr_doit(struct sk_buff *skb, struct genl_info *info) 1720{ 1721 return mptcp_pm_get_addr(skb, info); 1722} 1723 1724int mptcp_pm_nl_dump_addr(struct sk_buff *msg, 1725 struct netlink_callback *cb) 1726{ 1727 struct net *net = sock_net(msg->sk); 1728 struct mptcp_pm_addr_entry *entry; 1729 struct pm_nl_pernet *pernet; 1730 int id = cb->args[0]; 1731 void *hdr; 1732 int i; 1733 1734 pernet = pm_nl_get_pernet(net); 1735 1736 spin_lock_bh(&pernet->lock); 1737 for (i = id; i < MPTCP_PM_MAX_ADDR_ID + 1; i++) { 1738 if (test_bit(i, pernet->id_bitmap)) { 1739 entry = __lookup_addr_by_id(pernet, i); 1740 if (!entry) 1741 break; 1742 1743 if (entry->addr.id <= id) 1744 continue; 1745 1746 hdr = genlmsg_put(msg, NETLINK_CB(cb->skb).portid, 1747 cb->nlh->nlmsg_seq, &mptcp_genl_family, 1748 NLM_F_MULTI, MPTCP_PM_CMD_GET_ADDR); 1749 if (!hdr) 1750 break; 1751 1752 if (mptcp_nl_fill_addr(msg, entry) < 0) { 1753 genlmsg_cancel(msg, hdr); 1754 break; 1755 } 1756 1757 id = entry->addr.id; 1758 genlmsg_end(msg, hdr); 1759 } 1760 } 1761 spin_unlock_bh(&pernet->lock); 1762 1763 cb->args[0] = id; 1764 return msg->len; 1765} 1766 1767int mptcp_pm_nl_get_addr_dumpit(struct sk_buff *msg, 1768 struct netlink_callback *cb) 1769{ 1770 return mptcp_pm_dump_addr(msg, cb); 1771} 1772 1773static int parse_limit(struct genl_info *info, int id, unsigned int *limit) 1774{ 1775 struct nlattr *attr = info->attrs[id]; 1776 1777 if (!attr) 1778 return 0; 1779 1780 *limit = nla_get_u32(attr); 1781 if (*limit > MPTCP_PM_ADDR_MAX) { 1782 GENL_SET_ERR_MSG(info, "limit greater than maximum"); 1783 return -EINVAL; 1784 } 1785 return 0; 1786} 1787 1788int mptcp_pm_nl_set_limits_doit(struct sk_buff *skb, struct genl_info *info) 1789{ 1790 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1791 unsigned int rcv_addrs, subflows; 1792 int ret; 1793 1794 spin_lock_bh(&pernet->lock); 1795 rcv_addrs = pernet->add_addr_accept_max; 1796 ret = parse_limit(info, MPTCP_PM_ATTR_RCV_ADD_ADDRS, &rcv_addrs); 1797 if (ret) 1798 goto unlock; 1799 1800 subflows = pernet->subflows_max; 1801 ret = parse_limit(info, MPTCP_PM_ATTR_SUBFLOWS, &subflows); 1802 if (ret) 1803 goto unlock; 1804 1805 WRITE_ONCE(pernet->add_addr_accept_max, rcv_addrs); 1806 WRITE_ONCE(pernet->subflows_max, subflows); 1807 1808unlock: 1809 spin_unlock_bh(&pernet->lock); 1810 return ret; 1811} 1812 1813int mptcp_pm_nl_get_limits_doit(struct sk_buff *skb, struct genl_info *info) 1814{ 1815 struct pm_nl_pernet *pernet = genl_info_pm_nl(info); 1816 struct sk_buff *msg; 1817 void *reply; 1818 1819 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 1820 if (!msg) 1821 return -ENOMEM; 1822 1823 reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0, 1824 MPTCP_PM_CMD_GET_LIMITS); 1825 if (!reply) 1826 goto fail; 1827 1828 if (nla_put_u32(msg, MPTCP_PM_ATTR_RCV_ADD_ADDRS, 1829 READ_ONCE(pernet->add_addr_accept_max))) 1830 goto fail; 1831 1832 if (nla_put_u32(msg, MPTCP_PM_ATTR_SUBFLOWS, 1833 READ_ONCE(pernet->subflows_max))) 1834 goto fail; 1835 1836 genlmsg_end(msg, reply); 1837 return genlmsg_reply(msg, info); 1838 1839fail: 1840 GENL_SET_ERR_MSG(info, "not enough space in Netlink message"); 1841 nlmsg_free(msg); 1842 return -EMSGSIZE; 1843} 1844 1845static void mptcp_pm_nl_fullmesh(struct mptcp_sock *msk, 1846 struct mptcp_addr_info *addr) 1847{ 1848 struct mptcp_rm_list list = { .nr = 0 }; 1849 1850 list.ids[list.nr++] = addr->id; 1851 1852 spin_lock_bh(&msk->pm.lock); 1853 mptcp_pm_nl_rm_subflow_received(msk, &list); 1854 mptcp_pm_create_subflow_or_signal_addr(msk); 1855 spin_unlock_bh(&msk->pm.lock); 1856} 1857 1858static int mptcp_nl_set_flags(struct net *net, 1859 struct mptcp_addr_info *addr, 1860 u8 bkup, u8 changed) 1861{ 1862 long s_slot = 0, s_num = 0; 1863 struct mptcp_sock *msk; 1864 int ret = -EINVAL; 1865 1866 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { 1867 struct sock *sk = (struct sock *)msk; 1868 1869 if (list_empty(&msk->conn_list) || mptcp_pm_is_userspace(msk)) 1870 goto next; 1871 1872 lock_sock(sk); 1873 if (changed & MPTCP_PM_ADDR_FLAG_BACKUP) 1874 ret = mptcp_pm_nl_mp_prio_send_ack(msk, addr, NULL, bkup); 1875 if (changed & MPTCP_PM_ADDR_FLAG_FULLMESH) 1876 mptcp_pm_nl_fullmesh(msk, addr); 1877 release_sock(sk); 1878 1879next: 1880 sock_put(sk); 1881 cond_resched(); 1882 } 1883 1884 return ret; 1885} 1886 1887int mptcp_pm_nl_set_flags(struct sk_buff *skb, struct genl_info *info) 1888{ 1889 struct mptcp_pm_addr_entry addr = { .addr = { .family = AF_UNSPEC }, }; 1890 struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR]; 1891 u8 changed, mask = MPTCP_PM_ADDR_FLAG_BACKUP | 1892 MPTCP_PM_ADDR_FLAG_FULLMESH; 1893 struct net *net = sock_net(skb->sk); 1894 struct mptcp_pm_addr_entry *entry; 1895 struct pm_nl_pernet *pernet; 1896 u8 lookup_by_id = 0; 1897 u8 bkup = 0; 1898 int ret; 1899 1900 pernet = pm_nl_get_pernet(net); 1901 1902 ret = mptcp_pm_parse_entry(attr, info, false, &addr); 1903 if (ret < 0) 1904 return ret; 1905 1906 if (addr.addr.family == AF_UNSPEC) { 1907 lookup_by_id = 1; 1908 if (!addr.addr.id) { 1909 GENL_SET_ERR_MSG(info, "missing required inputs"); 1910 return -EOPNOTSUPP; 1911 } 1912 } 1913 1914 if (addr.flags & MPTCP_PM_ADDR_FLAG_BACKUP) 1915 bkup = 1; 1916 1917 spin_lock_bh(&pernet->lock); 1918 entry = lookup_by_id ? __lookup_addr_by_id(pernet, addr.addr.id) : 1919 __lookup_addr(pernet, &addr.addr); 1920 if (!entry) { 1921 spin_unlock_bh(&pernet->lock); 1922 GENL_SET_ERR_MSG(info, "address not found"); 1923 return -EINVAL; 1924 } 1925 if ((addr.flags & MPTCP_PM_ADDR_FLAG_FULLMESH) && 1926 (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) { 1927 spin_unlock_bh(&pernet->lock); 1928 GENL_SET_ERR_MSG(info, "invalid addr flags"); 1929 return -EINVAL; 1930 } 1931 1932 changed = (addr.flags ^ entry->flags) & mask; 1933 entry->flags = (entry->flags & ~mask) | (addr.flags & mask); 1934 addr = *entry; 1935 spin_unlock_bh(&pernet->lock); 1936 1937 mptcp_nl_set_flags(net, &addr.addr, bkup, changed); 1938 return 0; 1939} 1940 1941int mptcp_pm_nl_set_flags_doit(struct sk_buff *skb, struct genl_info *info) 1942{ 1943 return mptcp_pm_set_flags(skb, info); 1944} 1945 1946static void mptcp_nl_mcast_send(struct net *net, struct sk_buff *nlskb, gfp_t gfp) 1947{ 1948 genlmsg_multicast_netns(&mptcp_genl_family, net, 1949 nlskb, 0, MPTCP_PM_EV_GRP_OFFSET, gfp); 1950} 1951 1952bool mptcp_userspace_pm_active(const struct mptcp_sock *msk) 1953{ 1954 return genl_has_listeners(&mptcp_genl_family, 1955 sock_net((const struct sock *)msk), 1956 MPTCP_PM_EV_GRP_OFFSET); 1957} 1958 1959static int mptcp_event_add_subflow(struct sk_buff *skb, const struct sock *ssk) 1960{ 1961 const struct inet_sock *issk = inet_sk(ssk); 1962 const struct mptcp_subflow_context *sf; 1963 1964 if (nla_put_u16(skb, MPTCP_ATTR_FAMILY, ssk->sk_family)) 1965 return -EMSGSIZE; 1966 1967 switch (ssk->sk_family) { 1968 case AF_INET: 1969 if (nla_put_in_addr(skb, MPTCP_ATTR_SADDR4, issk->inet_saddr)) 1970 return -EMSGSIZE; 1971 if (nla_put_in_addr(skb, MPTCP_ATTR_DADDR4, issk->inet_daddr)) 1972 return -EMSGSIZE; 1973 break; 1974#if IS_ENABLED(CONFIG_MPTCP_IPV6) 1975 case AF_INET6: { 1976 const struct ipv6_pinfo *np = inet6_sk(ssk); 1977 1978 if (nla_put_in6_addr(skb, MPTCP_ATTR_SADDR6, &np->saddr)) 1979 return -EMSGSIZE; 1980 if (nla_put_in6_addr(skb, MPTCP_ATTR_DADDR6, &ssk->sk_v6_daddr)) 1981 return -EMSGSIZE; 1982 break; 1983 } 1984#endif 1985 default: 1986 WARN_ON_ONCE(1); 1987 return -EMSGSIZE; 1988 } 1989 1990 if (nla_put_be16(skb, MPTCP_ATTR_SPORT, issk->inet_sport)) 1991 return -EMSGSIZE; 1992 if (nla_put_be16(skb, MPTCP_ATTR_DPORT, issk->inet_dport)) 1993 return -EMSGSIZE; 1994 1995 sf = mptcp_subflow_ctx(ssk); 1996 if (WARN_ON_ONCE(!sf)) 1997 return -EINVAL; 1998 1999 if (nla_put_u8(skb, MPTCP_ATTR_LOC_ID, subflow_get_local_id(sf))) 2000 return -EMSGSIZE; 2001 2002 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, sf->remote_id)) 2003 return -EMSGSIZE; 2004 2005 return 0; 2006} 2007 2008static int mptcp_event_put_token_and_ssk(struct sk_buff *skb, 2009 const struct mptcp_sock *msk, 2010 const struct sock *ssk) 2011{ 2012 const struct sock *sk = (const struct sock *)msk; 2013 const struct mptcp_subflow_context *sf; 2014 u8 sk_err; 2015 2016 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, READ_ONCE(msk->token))) 2017 return -EMSGSIZE; 2018 2019 if (mptcp_event_add_subflow(skb, ssk)) 2020 return -EMSGSIZE; 2021 2022 sf = mptcp_subflow_ctx(ssk); 2023 if (WARN_ON_ONCE(!sf)) 2024 return -EINVAL; 2025 2026 if (nla_put_u8(skb, MPTCP_ATTR_BACKUP, sf->backup)) 2027 return -EMSGSIZE; 2028 2029 if (ssk->sk_bound_dev_if && 2030 nla_put_s32(skb, MPTCP_ATTR_IF_IDX, ssk->sk_bound_dev_if)) 2031 return -EMSGSIZE; 2032 2033 sk_err = READ_ONCE(ssk->sk_err); 2034 if (sk_err && sk->sk_state == TCP_ESTABLISHED && 2035 nla_put_u8(skb, MPTCP_ATTR_ERROR, sk_err)) 2036 return -EMSGSIZE; 2037 2038 return 0; 2039} 2040 2041static int mptcp_event_sub_established(struct sk_buff *skb, 2042 const struct mptcp_sock *msk, 2043 const struct sock *ssk) 2044{ 2045 return mptcp_event_put_token_and_ssk(skb, msk, ssk); 2046} 2047 2048static int mptcp_event_sub_closed(struct sk_buff *skb, 2049 const struct mptcp_sock *msk, 2050 const struct sock *ssk) 2051{ 2052 const struct mptcp_subflow_context *sf; 2053 2054 if (mptcp_event_put_token_and_ssk(skb, msk, ssk)) 2055 return -EMSGSIZE; 2056 2057 sf = mptcp_subflow_ctx(ssk); 2058 if (!sf->reset_seen) 2059 return 0; 2060 2061 if (nla_put_u32(skb, MPTCP_ATTR_RESET_REASON, sf->reset_reason)) 2062 return -EMSGSIZE; 2063 2064 if (nla_put_u32(skb, MPTCP_ATTR_RESET_FLAGS, sf->reset_transient)) 2065 return -EMSGSIZE; 2066 2067 return 0; 2068} 2069 2070static int mptcp_event_created(struct sk_buff *skb, 2071 const struct mptcp_sock *msk, 2072 const struct sock *ssk) 2073{ 2074 int err = nla_put_u32(skb, MPTCP_ATTR_TOKEN, READ_ONCE(msk->token)); 2075 2076 if (err) 2077 return err; 2078 2079 if (nla_put_u8(skb, MPTCP_ATTR_SERVER_SIDE, READ_ONCE(msk->pm.server_side))) 2080 return -EMSGSIZE; 2081 2082 return mptcp_event_add_subflow(skb, ssk); 2083} 2084 2085void mptcp_event_addr_removed(const struct mptcp_sock *msk, uint8_t id) 2086{ 2087 struct net *net = sock_net((const struct sock *)msk); 2088 struct nlmsghdr *nlh; 2089 struct sk_buff *skb; 2090 2091 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2092 return; 2093 2094 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); 2095 if (!skb) 2096 return; 2097 2098 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, MPTCP_EVENT_REMOVED); 2099 if (!nlh) 2100 goto nla_put_failure; 2101 2102 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, READ_ONCE(msk->token))) 2103 goto nla_put_failure; 2104 2105 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, id)) 2106 goto nla_put_failure; 2107 2108 genlmsg_end(skb, nlh); 2109 mptcp_nl_mcast_send(net, skb, GFP_ATOMIC); 2110 return; 2111 2112nla_put_failure: 2113 nlmsg_free(skb); 2114} 2115 2116void mptcp_event_addr_announced(const struct sock *ssk, 2117 const struct mptcp_addr_info *info) 2118{ 2119 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 2120 struct mptcp_sock *msk = mptcp_sk(subflow->conn); 2121 struct net *net = sock_net(ssk); 2122 struct nlmsghdr *nlh; 2123 struct sk_buff *skb; 2124 2125 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2126 return; 2127 2128 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); 2129 if (!skb) 2130 return; 2131 2132 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, 2133 MPTCP_EVENT_ANNOUNCED); 2134 if (!nlh) 2135 goto nla_put_failure; 2136 2137 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, READ_ONCE(msk->token))) 2138 goto nla_put_failure; 2139 2140 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, info->id)) 2141 goto nla_put_failure; 2142 2143 if (nla_put_be16(skb, MPTCP_ATTR_DPORT, 2144 info->port == 0 ? 2145 inet_sk(ssk)->inet_dport : 2146 info->port)) 2147 goto nla_put_failure; 2148 2149 switch (info->family) { 2150 case AF_INET: 2151 if (nla_put_in_addr(skb, MPTCP_ATTR_DADDR4, info->addr.s_addr)) 2152 goto nla_put_failure; 2153 break; 2154#if IS_ENABLED(CONFIG_MPTCP_IPV6) 2155 case AF_INET6: 2156 if (nla_put_in6_addr(skb, MPTCP_ATTR_DADDR6, &info->addr6)) 2157 goto nla_put_failure; 2158 break; 2159#endif 2160 default: 2161 WARN_ON_ONCE(1); 2162 goto nla_put_failure; 2163 } 2164 2165 genlmsg_end(skb, nlh); 2166 mptcp_nl_mcast_send(net, skb, GFP_ATOMIC); 2167 return; 2168 2169nla_put_failure: 2170 nlmsg_free(skb); 2171} 2172 2173void mptcp_event_pm_listener(const struct sock *ssk, 2174 enum mptcp_event_type event) 2175{ 2176 const struct inet_sock *issk = inet_sk(ssk); 2177 struct net *net = sock_net(ssk); 2178 struct nlmsghdr *nlh; 2179 struct sk_buff *skb; 2180 2181 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2182 return; 2183 2184 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 2185 if (!skb) 2186 return; 2187 2188 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, event); 2189 if (!nlh) 2190 goto nla_put_failure; 2191 2192 if (nla_put_u16(skb, MPTCP_ATTR_FAMILY, ssk->sk_family)) 2193 goto nla_put_failure; 2194 2195 if (nla_put_be16(skb, MPTCP_ATTR_SPORT, issk->inet_sport)) 2196 goto nla_put_failure; 2197 2198 switch (ssk->sk_family) { 2199 case AF_INET: 2200 if (nla_put_in_addr(skb, MPTCP_ATTR_SADDR4, issk->inet_saddr)) 2201 goto nla_put_failure; 2202 break; 2203#if IS_ENABLED(CONFIG_MPTCP_IPV6) 2204 case AF_INET6: { 2205 const struct ipv6_pinfo *np = inet6_sk(ssk); 2206 2207 if (nla_put_in6_addr(skb, MPTCP_ATTR_SADDR6, &np->saddr)) 2208 goto nla_put_failure; 2209 break; 2210 } 2211#endif 2212 default: 2213 WARN_ON_ONCE(1); 2214 goto nla_put_failure; 2215 } 2216 2217 genlmsg_end(skb, nlh); 2218 mptcp_nl_mcast_send(net, skb, GFP_KERNEL); 2219 return; 2220 2221nla_put_failure: 2222 nlmsg_free(skb); 2223} 2224 2225void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk, 2226 const struct sock *ssk, gfp_t gfp) 2227{ 2228 struct net *net = sock_net((const struct sock *)msk); 2229 struct nlmsghdr *nlh; 2230 struct sk_buff *skb; 2231 2232 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET)) 2233 return; 2234 2235 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, gfp); 2236 if (!skb) 2237 return; 2238 2239 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, type); 2240 if (!nlh) 2241 goto nla_put_failure; 2242 2243 switch (type) { 2244 case MPTCP_EVENT_UNSPEC: 2245 WARN_ON_ONCE(1); 2246 break; 2247 case MPTCP_EVENT_CREATED: 2248 case MPTCP_EVENT_ESTABLISHED: 2249 if (mptcp_event_created(skb, msk, ssk) < 0) 2250 goto nla_put_failure; 2251 break; 2252 case MPTCP_EVENT_CLOSED: 2253 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, READ_ONCE(msk->token)) < 0) 2254 goto nla_put_failure; 2255 break; 2256 case MPTCP_EVENT_ANNOUNCED: 2257 case MPTCP_EVENT_REMOVED: 2258 /* call mptcp_event_addr_announced()/removed instead */ 2259 WARN_ON_ONCE(1); 2260 break; 2261 case MPTCP_EVENT_SUB_ESTABLISHED: 2262 case MPTCP_EVENT_SUB_PRIORITY: 2263 if (mptcp_event_sub_established(skb, msk, ssk) < 0) 2264 goto nla_put_failure; 2265 break; 2266 case MPTCP_EVENT_SUB_CLOSED: 2267 if (mptcp_event_sub_closed(skb, msk, ssk) < 0) 2268 goto nla_put_failure; 2269 break; 2270 case MPTCP_EVENT_LISTENER_CREATED: 2271 case MPTCP_EVENT_LISTENER_CLOSED: 2272 break; 2273 } 2274 2275 genlmsg_end(skb, nlh); 2276 mptcp_nl_mcast_send(net, skb, gfp); 2277 return; 2278 2279nla_put_failure: 2280 nlmsg_free(skb); 2281} 2282 2283struct genl_family mptcp_genl_family __ro_after_init = { 2284 .name = MPTCP_PM_NAME, 2285 .version = MPTCP_PM_VER, 2286 .netnsok = true, 2287 .module = THIS_MODULE, 2288 .ops = mptcp_pm_nl_ops, 2289 .n_ops = ARRAY_SIZE(mptcp_pm_nl_ops), 2290 .resv_start_op = MPTCP_PM_CMD_SUBFLOW_DESTROY + 1, 2291 .mcgrps = mptcp_pm_mcgrps, 2292 .n_mcgrps = ARRAY_SIZE(mptcp_pm_mcgrps), 2293}; 2294 2295static int __net_init pm_nl_init_net(struct net *net) 2296{ 2297 struct pm_nl_pernet *pernet = pm_nl_get_pernet(net); 2298 2299 INIT_LIST_HEAD_RCU(&pernet->local_addr_list); 2300 2301 /* Cit. 2 subflows ought to be enough for anybody. */ 2302 pernet->subflows_max = 2; 2303 pernet->next_id = 1; 2304 pernet->stale_loss_cnt = 4; 2305 spin_lock_init(&pernet->lock); 2306 2307 /* No need to initialize other pernet fields, the struct is zeroed at 2308 * allocation time. 2309 */ 2310 2311 return 0; 2312} 2313 2314static void __net_exit pm_nl_exit_net(struct list_head *net_list) 2315{ 2316 struct net *net; 2317 2318 list_for_each_entry(net, net_list, exit_list) { 2319 struct pm_nl_pernet *pernet = pm_nl_get_pernet(net); 2320 2321 /* net is removed from namespace list, can't race with 2322 * other modifiers, also netns core already waited for a 2323 * RCU grace period. 2324 */ 2325 __flush_addrs(&pernet->local_addr_list); 2326 } 2327} 2328 2329static struct pernet_operations mptcp_pm_pernet_ops = { 2330 .init = pm_nl_init_net, 2331 .exit_batch = pm_nl_exit_net, 2332 .id = &pm_nl_pernet_id, 2333 .size = sizeof(struct pm_nl_pernet), 2334}; 2335 2336void __init mptcp_pm_nl_init(void) 2337{ 2338 if (register_pernet_subsys(&mptcp_pm_pernet_ops) < 0) 2339 panic("Failed to register MPTCP PM pernet subsystem.\n"); 2340 2341 if (genl_register_family(&mptcp_genl_family)) 2342 panic("Failed to register MPTCP PM netlink family\n"); 2343} 2344