1// SPDX-License-Identifier: GPL-2.0
2/* Multipath TCP
3 *
4 * Copyright (c) 2020, Red Hat, Inc.
5 */
6
7#define pr_fmt(fmt) "MPTCP: " fmt
8
9#include <linux/inet.h>
10#include <linux/kernel.h>
11#include <net/tcp.h>
12#include <net/inet_common.h>
13#include <net/netns/generic.h>
14#include <net/mptcp.h>
15#include <net/genetlink.h>
16#include <uapi/linux/mptcp.h>
17
18#include "protocol.h"
19#include "mib.h"
20
21/* forward declaration */
22static struct genl_family mptcp_genl_family;
23
24static int pm_nl_pernet_id;
25
26struct mptcp_pm_add_entry {
27 struct list_head list;
28 struct mptcp_addr_info addr;
29 u8 retrans_times;
30 struct timer_list add_timer;
31 struct mptcp_sock *sock;
32};
33
34struct pm_nl_pernet {
35 /* protects pernet updates */
36 spinlock_t lock;
37 struct list_head local_addr_list;
38 unsigned int addrs;
39 unsigned int stale_loss_cnt;
40 unsigned int add_addr_signal_max;
41 unsigned int add_addr_accept_max;
42 unsigned int local_addr_max;
43 unsigned int subflows_max;
44 unsigned int next_id;
45 DECLARE_BITMAP(id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1);
46};
47
48#define MPTCP_PM_ADDR_MAX 8
49#define ADD_ADDR_RETRANS_MAX 3
50
51static struct pm_nl_pernet *pm_nl_get_pernet(const struct net *net)
52{
53 return net_generic(net, id: pm_nl_pernet_id);
54}
55
56static struct pm_nl_pernet *
57pm_nl_get_pernet_from_msk(const struct mptcp_sock *msk)
58{
59 return pm_nl_get_pernet(net: sock_net(sk: (struct sock *)msk));
60}
61
62bool mptcp_addresses_equal(const struct mptcp_addr_info *a,
63 const struct mptcp_addr_info *b, bool use_port)
64{
65 bool addr_equals = false;
66
67 if (a->family == b->family) {
68 if (a->family == AF_INET)
69 addr_equals = a->addr.s_addr == b->addr.s_addr;
70#if IS_ENABLED(CONFIG_MPTCP_IPV6)
71 else
72 addr_equals = !ipv6_addr_cmp(a1: &a->addr6, a2: &b->addr6);
73 } else if (a->family == AF_INET) {
74 if (ipv6_addr_v4mapped(a: &b->addr6))
75 addr_equals = a->addr.s_addr == b->addr6.s6_addr32[3];
76 } else if (b->family == AF_INET) {
77 if (ipv6_addr_v4mapped(a: &a->addr6))
78 addr_equals = a->addr6.s6_addr32[3] == b->addr.s_addr;
79#endif
80 }
81
82 if (!addr_equals)
83 return false;
84 if (!use_port)
85 return true;
86
87 return a->port == b->port;
88}
89
90void mptcp_local_address(const struct sock_common *skc, struct mptcp_addr_info *addr)
91{
92 addr->family = skc->skc_family;
93 addr->port = htons(skc->skc_num);
94 if (addr->family == AF_INET)
95 addr->addr.s_addr = skc->skc_rcv_saddr;
96#if IS_ENABLED(CONFIG_MPTCP_IPV6)
97 else if (addr->family == AF_INET6)
98 addr->addr6 = skc->skc_v6_rcv_saddr;
99#endif
100}
101
102static void remote_address(const struct sock_common *skc,
103 struct mptcp_addr_info *addr)
104{
105 addr->family = skc->skc_family;
106 addr->port = skc->skc_dport;
107 if (addr->family == AF_INET)
108 addr->addr.s_addr = skc->skc_daddr;
109#if IS_ENABLED(CONFIG_MPTCP_IPV6)
110 else if (addr->family == AF_INET6)
111 addr->addr6 = skc->skc_v6_daddr;
112#endif
113}
114
115static bool lookup_subflow_by_saddr(const struct list_head *list,
116 const struct mptcp_addr_info *saddr)
117{
118 struct mptcp_subflow_context *subflow;
119 struct mptcp_addr_info cur;
120 struct sock_common *skc;
121
122 list_for_each_entry(subflow, list, node) {
123 skc = (struct sock_common *)mptcp_subflow_tcp_sock(subflow);
124
125 mptcp_local_address(skc, addr: &cur);
126 if (mptcp_addresses_equal(a: &cur, b: saddr, use_port: saddr->port))
127 return true;
128 }
129
130 return false;
131}
132
133static bool lookup_subflow_by_daddr(const struct list_head *list,
134 const struct mptcp_addr_info *daddr)
135{
136 struct mptcp_subflow_context *subflow;
137 struct mptcp_addr_info cur;
138 struct sock_common *skc;
139
140 list_for_each_entry(subflow, list, node) {
141 skc = (struct sock_common *)mptcp_subflow_tcp_sock(subflow);
142
143 remote_address(skc, addr: &cur);
144 if (mptcp_addresses_equal(a: &cur, b: daddr, use_port: daddr->port))
145 return true;
146 }
147
148 return false;
149}
150
151static struct mptcp_pm_addr_entry *
152select_local_address(const struct pm_nl_pernet *pernet,
153 const struct mptcp_sock *msk)
154{
155 struct mptcp_pm_addr_entry *entry, *ret = NULL;
156
157 msk_owned_by_me(msk);
158
159 rcu_read_lock();
160 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) {
161 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW))
162 continue;
163
164 if (!test_bit(entry->addr.id, msk->pm.id_avail_bitmap))
165 continue;
166
167 ret = entry;
168 break;
169 }
170 rcu_read_unlock();
171 return ret;
172}
173
174static struct mptcp_pm_addr_entry *
175select_signal_address(struct pm_nl_pernet *pernet, const struct mptcp_sock *msk)
176{
177 struct mptcp_pm_addr_entry *entry, *ret = NULL;
178
179 rcu_read_lock();
180 /* do not keep any additional per socket state, just signal
181 * the address list in order.
182 * Note: removal from the local address list during the msk life-cycle
183 * can lead to additional addresses not being announced.
184 */
185 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) {
186 if (!test_bit(entry->addr.id, msk->pm.id_avail_bitmap))
187 continue;
188
189 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL))
190 continue;
191
192 ret = entry;
193 break;
194 }
195 rcu_read_unlock();
196 return ret;
197}
198
199unsigned int mptcp_pm_get_add_addr_signal_max(const struct mptcp_sock *msk)
200{
201 const struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk);
202
203 return READ_ONCE(pernet->add_addr_signal_max);
204}
205EXPORT_SYMBOL_GPL(mptcp_pm_get_add_addr_signal_max);
206
207unsigned int mptcp_pm_get_add_addr_accept_max(const struct mptcp_sock *msk)
208{
209 struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk);
210
211 return READ_ONCE(pernet->add_addr_accept_max);
212}
213EXPORT_SYMBOL_GPL(mptcp_pm_get_add_addr_accept_max);
214
215unsigned int mptcp_pm_get_subflows_max(const struct mptcp_sock *msk)
216{
217 struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk);
218
219 return READ_ONCE(pernet->subflows_max);
220}
221EXPORT_SYMBOL_GPL(mptcp_pm_get_subflows_max);
222
223unsigned int mptcp_pm_get_local_addr_max(const struct mptcp_sock *msk)
224{
225 struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk);
226
227 return READ_ONCE(pernet->local_addr_max);
228}
229EXPORT_SYMBOL_GPL(mptcp_pm_get_local_addr_max);
230
231bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk)
232{
233 struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk);
234
235 if (msk->pm.subflows == mptcp_pm_get_subflows_max(msk) ||
236 (find_next_and_bit(addr1: pernet->id_bitmap, addr2: msk->pm.id_avail_bitmap,
237 MPTCP_PM_MAX_ADDR_ID + 1, offset: 0) == MPTCP_PM_MAX_ADDR_ID + 1)) {
238 WRITE_ONCE(msk->pm.work_pending, false);
239 return false;
240 }
241 return true;
242}
243
244struct mptcp_pm_add_entry *
245mptcp_lookup_anno_list_by_saddr(const struct mptcp_sock *msk,
246 const struct mptcp_addr_info *addr)
247{
248 struct mptcp_pm_add_entry *entry;
249
250 lockdep_assert_held(&msk->pm.lock);
251
252 list_for_each_entry(entry, &msk->pm.anno_list, list) {
253 if (mptcp_addresses_equal(a: &entry->addr, b: addr, use_port: true))
254 return entry;
255 }
256
257 return NULL;
258}
259
260bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk)
261{
262 struct mptcp_pm_add_entry *entry;
263 struct mptcp_addr_info saddr;
264 bool ret = false;
265
266 mptcp_local_address(skc: (struct sock_common *)sk, addr: &saddr);
267
268 spin_lock_bh(lock: &msk->pm.lock);
269 list_for_each_entry(entry, &msk->pm.anno_list, list) {
270 if (mptcp_addresses_equal(a: &entry->addr, b: &saddr, use_port: true)) {
271 ret = true;
272 goto out;
273 }
274 }
275
276out:
277 spin_unlock_bh(lock: &msk->pm.lock);
278 return ret;
279}
280
281static void mptcp_pm_add_timer(struct timer_list *timer)
282{
283 struct mptcp_pm_add_entry *entry = from_timer(entry, timer, add_timer);
284 struct mptcp_sock *msk = entry->sock;
285 struct sock *sk = (struct sock *)msk;
286
287 pr_debug("msk=%p", msk);
288
289 if (!msk)
290 return;
291
292 if (inet_sk_state_load(sk) == TCP_CLOSE)
293 return;
294
295 if (!entry->addr.id)
296 return;
297
298 if (mptcp_pm_should_add_signal_addr(msk)) {
299 sk_reset_timer(sk, timer, expires: jiffies + TCP_RTO_MAX / 8);
300 goto out;
301 }
302
303 spin_lock_bh(lock: &msk->pm.lock);
304
305 if (!mptcp_pm_should_add_signal_addr(msk)) {
306 pr_debug("retransmit ADD_ADDR id=%d", entry->addr.id);
307 mptcp_pm_announce_addr(msk, addr: &entry->addr, echo: false);
308 mptcp_pm_add_addr_send_ack(msk);
309 entry->retrans_times++;
310 }
311
312 if (entry->retrans_times < ADD_ADDR_RETRANS_MAX)
313 sk_reset_timer(sk, timer,
314 expires: jiffies + mptcp_get_add_addr_timeout(net: sock_net(sk)));
315
316 spin_unlock_bh(lock: &msk->pm.lock);
317
318 if (entry->retrans_times == ADD_ADDR_RETRANS_MAX)
319 mptcp_pm_subflow_established(msk);
320
321out:
322 __sock_put(sk);
323}
324
325struct mptcp_pm_add_entry *
326mptcp_pm_del_add_timer(struct mptcp_sock *msk,
327 const struct mptcp_addr_info *addr, bool check_id)
328{
329 struct mptcp_pm_add_entry *entry;
330 struct sock *sk = (struct sock *)msk;
331
332 spin_lock_bh(lock: &msk->pm.lock);
333 entry = mptcp_lookup_anno_list_by_saddr(msk, addr);
334 if (entry && (!check_id || entry->addr.id == addr->id))
335 entry->retrans_times = ADD_ADDR_RETRANS_MAX;
336 spin_unlock_bh(lock: &msk->pm.lock);
337
338 if (entry && (!check_id || entry->addr.id == addr->id))
339 sk_stop_timer_sync(sk, timer: &entry->add_timer);
340
341 return entry;
342}
343
344bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk,
345 const struct mptcp_addr_info *addr)
346{
347 struct mptcp_pm_add_entry *add_entry = NULL;
348 struct sock *sk = (struct sock *)msk;
349 struct net *net = sock_net(sk);
350
351 lockdep_assert_held(&msk->pm.lock);
352
353 add_entry = mptcp_lookup_anno_list_by_saddr(msk, addr);
354
355 if (add_entry) {
356 if (mptcp_pm_is_kernel(msk))
357 return false;
358
359 sk_reset_timer(sk, timer: &add_entry->add_timer,
360 expires: jiffies + mptcp_get_add_addr_timeout(net));
361 return true;
362 }
363
364 add_entry = kmalloc(size: sizeof(*add_entry), GFP_ATOMIC);
365 if (!add_entry)
366 return false;
367
368 list_add(new: &add_entry->list, head: &msk->pm.anno_list);
369
370 add_entry->addr = *addr;
371 add_entry->sock = msk;
372 add_entry->retrans_times = 0;
373
374 timer_setup(&add_entry->add_timer, mptcp_pm_add_timer, 0);
375 sk_reset_timer(sk, timer: &add_entry->add_timer,
376 expires: jiffies + mptcp_get_add_addr_timeout(net));
377
378 return true;
379}
380
381void mptcp_pm_free_anno_list(struct mptcp_sock *msk)
382{
383 struct mptcp_pm_add_entry *entry, *tmp;
384 struct sock *sk = (struct sock *)msk;
385 LIST_HEAD(free_list);
386
387 pr_debug("msk=%p", msk);
388
389 spin_lock_bh(lock: &msk->pm.lock);
390 list_splice_init(list: &msk->pm.anno_list, head: &free_list);
391 spin_unlock_bh(lock: &msk->pm.lock);
392
393 list_for_each_entry_safe(entry, tmp, &free_list, list) {
394 sk_stop_timer_sync(sk, timer: &entry->add_timer);
395 kfree(objp: entry);
396 }
397}
398
399static bool lookup_address_in_vec(const struct mptcp_addr_info *addrs, unsigned int nr,
400 const struct mptcp_addr_info *addr)
401{
402 int i;
403
404 for (i = 0; i < nr; i++) {
405 if (addrs[i].id == addr->id)
406 return true;
407 }
408
409 return false;
410}
411
412/* Fill all the remote addresses into the array addrs[],
413 * and return the array size.
414 */
415static unsigned int fill_remote_addresses_vec(struct mptcp_sock *msk,
416 struct mptcp_addr_info *local,
417 bool fullmesh,
418 struct mptcp_addr_info *addrs)
419{
420 bool deny_id0 = READ_ONCE(msk->pm.remote_deny_join_id0);
421 struct sock *sk = (struct sock *)msk, *ssk;
422 struct mptcp_subflow_context *subflow;
423 struct mptcp_addr_info remote = { 0 };
424 unsigned int subflows_max;
425 int i = 0;
426
427 subflows_max = mptcp_pm_get_subflows_max(msk);
428 remote_address(skc: (struct sock_common *)sk, addr: &remote);
429
430 /* Non-fullmesh endpoint, fill in the single entry
431 * corresponding to the primary MPC subflow remote address
432 */
433 if (!fullmesh) {
434 if (deny_id0)
435 return 0;
436
437 if (!mptcp_pm_addr_families_match(sk, loc: local, rem: &remote))
438 return 0;
439
440 msk->pm.subflows++;
441 addrs[i++] = remote;
442 } else {
443 mptcp_for_each_subflow(msk, subflow) {
444 ssk = mptcp_subflow_tcp_sock(subflow);
445 remote_address(skc: (struct sock_common *)ssk, addr: &addrs[i]);
446 addrs[i].id = subflow->remote_id;
447 if (deny_id0 && !addrs[i].id)
448 continue;
449
450 if (!mptcp_pm_addr_families_match(sk, loc: local, rem: &addrs[i]))
451 continue;
452
453 if (!lookup_address_in_vec(addrs, nr: i, addr: &addrs[i]) &&
454 msk->pm.subflows < subflows_max) {
455 msk->pm.subflows++;
456 i++;
457 }
458 }
459 }
460
461 return i;
462}
463
464static void __mptcp_pm_send_ack(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow,
465 bool prio, bool backup)
466{
467 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
468 bool slow;
469
470 pr_debug("send ack for %s",
471 prio ? "mp_prio" : (mptcp_pm_should_add_signal(msk) ? "add_addr" : "rm_addr"));
472
473 slow = lock_sock_fast(sk: ssk);
474 if (prio) {
475 subflow->send_mp_prio = 1;
476 subflow->backup = backup;
477 subflow->request_bkup = backup;
478 }
479
480 __mptcp_subflow_send_ack(ssk);
481 unlock_sock_fast(sk: ssk, slow);
482}
483
484static void mptcp_pm_send_ack(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow,
485 bool prio, bool backup)
486{
487 spin_unlock_bh(lock: &msk->pm.lock);
488 __mptcp_pm_send_ack(msk, subflow, prio, backup);
489 spin_lock_bh(lock: &msk->pm.lock);
490}
491
492static struct mptcp_pm_addr_entry *
493__lookup_addr_by_id(struct pm_nl_pernet *pernet, unsigned int id)
494{
495 struct mptcp_pm_addr_entry *entry;
496
497 list_for_each_entry(entry, &pernet->local_addr_list, list) {
498 if (entry->addr.id == id)
499 return entry;
500 }
501 return NULL;
502}
503
504static struct mptcp_pm_addr_entry *
505__lookup_addr(struct pm_nl_pernet *pernet, const struct mptcp_addr_info *info,
506 bool lookup_by_id)
507{
508 struct mptcp_pm_addr_entry *entry;
509
510 list_for_each_entry(entry, &pernet->local_addr_list, list) {
511 if ((!lookup_by_id &&
512 mptcp_addresses_equal(a: &entry->addr, b: info, use_port: entry->addr.port)) ||
513 (lookup_by_id && entry->addr.id == info->id))
514 return entry;
515 }
516 return NULL;
517}
518
519static void mptcp_pm_create_subflow_or_signal_addr(struct mptcp_sock *msk)
520{
521 struct sock *sk = (struct sock *)msk;
522 struct mptcp_pm_addr_entry *local;
523 unsigned int add_addr_signal_max;
524 unsigned int local_addr_max;
525 struct pm_nl_pernet *pernet;
526 unsigned int subflows_max;
527
528 pernet = pm_nl_get_pernet(net: sock_net(sk));
529
530 add_addr_signal_max = mptcp_pm_get_add_addr_signal_max(msk);
531 local_addr_max = mptcp_pm_get_local_addr_max(msk);
532 subflows_max = mptcp_pm_get_subflows_max(msk);
533
534 /* do lazy endpoint usage accounting for the MPC subflows */
535 if (unlikely(!(msk->pm.status & BIT(MPTCP_PM_MPC_ENDPOINT_ACCOUNTED))) && msk->first) {
536 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk: msk->first);
537 struct mptcp_pm_addr_entry *entry;
538 struct mptcp_addr_info mpc_addr;
539 bool backup = false;
540
541 mptcp_local_address(skc: (struct sock_common *)msk->first, addr: &mpc_addr);
542 rcu_read_lock();
543 entry = __lookup_addr(pernet, info: &mpc_addr, lookup_by_id: false);
544 if (entry) {
545 __clear_bit(entry->addr.id, msk->pm.id_avail_bitmap);
546 msk->mpc_endpoint_id = entry->addr.id;
547 backup = !!(entry->flags & MPTCP_PM_ADDR_FLAG_BACKUP);
548 }
549 rcu_read_unlock();
550
551 if (backup)
552 mptcp_pm_send_ack(msk, subflow, prio: true, backup);
553
554 msk->pm.status |= BIT(MPTCP_PM_MPC_ENDPOINT_ACCOUNTED);
555 }
556
557 pr_debug("local %d:%d signal %d:%d subflows %d:%d\n",
558 msk->pm.local_addr_used, local_addr_max,
559 msk->pm.add_addr_signaled, add_addr_signal_max,
560 msk->pm.subflows, subflows_max);
561
562 /* check first for announce */
563 if (msk->pm.add_addr_signaled < add_addr_signal_max) {
564 local = select_signal_address(pernet, msk);
565
566 /* due to racing events on both ends we can reach here while
567 * previous add address is still running: if we invoke now
568 * mptcp_pm_announce_addr(), that will fail and the
569 * corresponding id will be marked as used.
570 * Instead let the PM machinery reschedule us when the
571 * current address announce will be completed.
572 */
573 if (msk->pm.addr_signal & BIT(MPTCP_ADD_ADDR_SIGNAL))
574 return;
575
576 if (local) {
577 if (mptcp_pm_alloc_anno_list(msk, addr: &local->addr)) {
578 __clear_bit(local->addr.id, msk->pm.id_avail_bitmap);
579 msk->pm.add_addr_signaled++;
580 mptcp_pm_announce_addr(msk, addr: &local->addr, echo: false);
581 mptcp_pm_nl_addr_send_ack(msk);
582 }
583 }
584 }
585
586 /* check if should create a new subflow */
587 while (msk->pm.local_addr_used < local_addr_max &&
588 msk->pm.subflows < subflows_max) {
589 struct mptcp_addr_info addrs[MPTCP_PM_ADDR_MAX];
590 bool fullmesh;
591 int i, nr;
592
593 local = select_local_address(pernet, msk);
594 if (!local)
595 break;
596
597 fullmesh = !!(local->flags & MPTCP_PM_ADDR_FLAG_FULLMESH);
598
599 msk->pm.local_addr_used++;
600 __clear_bit(local->addr.id, msk->pm.id_avail_bitmap);
601 nr = fill_remote_addresses_vec(msk, local: &local->addr, fullmesh, addrs);
602 if (nr == 0)
603 continue;
604
605 spin_unlock_bh(lock: &msk->pm.lock);
606 for (i = 0; i < nr; i++)
607 __mptcp_subflow_connect(sk, loc: &local->addr, remote: &addrs[i]);
608 spin_lock_bh(lock: &msk->pm.lock);
609 }
610 mptcp_pm_nl_check_work_pending(msk);
611}
612
613static void mptcp_pm_nl_fully_established(struct mptcp_sock *msk)
614{
615 mptcp_pm_create_subflow_or_signal_addr(msk);
616}
617
618static void mptcp_pm_nl_subflow_established(struct mptcp_sock *msk)
619{
620 mptcp_pm_create_subflow_or_signal_addr(msk);
621}
622
623/* Fill all the local addresses into the array addrs[],
624 * and return the array size.
625 */
626static unsigned int fill_local_addresses_vec(struct mptcp_sock *msk,
627 struct mptcp_addr_info *remote,
628 struct mptcp_addr_info *addrs)
629{
630 struct sock *sk = (struct sock *)msk;
631 struct mptcp_pm_addr_entry *entry;
632 struct pm_nl_pernet *pernet;
633 unsigned int subflows_max;
634 int i = 0;
635
636 pernet = pm_nl_get_pernet_from_msk(msk);
637 subflows_max = mptcp_pm_get_subflows_max(msk);
638
639 rcu_read_lock();
640 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) {
641 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_FULLMESH))
642 continue;
643
644 if (!mptcp_pm_addr_families_match(sk, loc: &entry->addr, rem: remote))
645 continue;
646
647 if (msk->pm.subflows < subflows_max) {
648 msk->pm.subflows++;
649 addrs[i++] = entry->addr;
650 }
651 }
652 rcu_read_unlock();
653
654 /* If the array is empty, fill in the single
655 * 'IPADDRANY' local address
656 */
657 if (!i) {
658 struct mptcp_addr_info local;
659
660 memset(&local, 0, sizeof(local));
661 local.family =
662#if IS_ENABLED(CONFIG_MPTCP_IPV6)
663 remote->family == AF_INET6 &&
664 ipv6_addr_v4mapped(a: &remote->addr6) ? AF_INET :
665#endif
666 remote->family;
667
668 if (!mptcp_pm_addr_families_match(sk, loc: &local, rem: remote))
669 return 0;
670
671 msk->pm.subflows++;
672 addrs[i++] = local;
673 }
674
675 return i;
676}
677
678static void mptcp_pm_nl_add_addr_received(struct mptcp_sock *msk)
679{
680 struct mptcp_addr_info addrs[MPTCP_PM_ADDR_MAX];
681 struct sock *sk = (struct sock *)msk;
682 unsigned int add_addr_accept_max;
683 struct mptcp_addr_info remote;
684 unsigned int subflows_max;
685 int i, nr;
686
687 add_addr_accept_max = mptcp_pm_get_add_addr_accept_max(msk);
688 subflows_max = mptcp_pm_get_subflows_max(msk);
689
690 pr_debug("accepted %d:%d remote family %d",
691 msk->pm.add_addr_accepted, add_addr_accept_max,
692 msk->pm.remote.family);
693
694 remote = msk->pm.remote;
695 mptcp_pm_announce_addr(msk, addr: &remote, echo: true);
696 mptcp_pm_nl_addr_send_ack(msk);
697
698 if (lookup_subflow_by_daddr(list: &msk->conn_list, daddr: &remote))
699 return;
700
701 /* pick id 0 port, if none is provided the remote address */
702 if (!remote.port)
703 remote.port = sk->sk_dport;
704
705 /* connect to the specified remote address, using whatever
706 * local address the routing configuration will pick.
707 */
708 nr = fill_local_addresses_vec(msk, remote: &remote, addrs);
709 if (nr == 0)
710 return;
711
712 msk->pm.add_addr_accepted++;
713 if (msk->pm.add_addr_accepted >= add_addr_accept_max ||
714 msk->pm.subflows >= subflows_max)
715 WRITE_ONCE(msk->pm.accept_addr, false);
716
717 spin_unlock_bh(lock: &msk->pm.lock);
718 for (i = 0; i < nr; i++)
719 __mptcp_subflow_connect(sk, loc: &addrs[i], remote: &remote);
720 spin_lock_bh(lock: &msk->pm.lock);
721}
722
723void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk)
724{
725 struct mptcp_subflow_context *subflow;
726
727 msk_owned_by_me(msk);
728 lockdep_assert_held(&msk->pm.lock);
729
730 if (!mptcp_pm_should_add_signal(msk) &&
731 !mptcp_pm_should_rm_signal(msk))
732 return;
733
734 subflow = list_first_entry_or_null(&msk->conn_list, typeof(*subflow), node);
735 if (subflow)
736 mptcp_pm_send_ack(msk, subflow, prio: false, backup: false);
737}
738
739int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk,
740 struct mptcp_addr_info *addr,
741 struct mptcp_addr_info *rem,
742 u8 bkup)
743{
744 struct mptcp_subflow_context *subflow;
745
746 pr_debug("bkup=%d", bkup);
747
748 mptcp_for_each_subflow(msk, subflow) {
749 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
750 struct mptcp_addr_info local, remote;
751
752 mptcp_local_address(skc: (struct sock_common *)ssk, addr: &local);
753 if (!mptcp_addresses_equal(a: &local, b: addr, use_port: addr->port))
754 continue;
755
756 if (rem && rem->family != AF_UNSPEC) {
757 remote_address(skc: (struct sock_common *)ssk, addr: &remote);
758 if (!mptcp_addresses_equal(a: &remote, b: rem, use_port: rem->port))
759 continue;
760 }
761
762 __mptcp_pm_send_ack(msk, subflow, prio: true, backup: bkup);
763 return 0;
764 }
765
766 return -EINVAL;
767}
768
769static bool mptcp_local_id_match(const struct mptcp_sock *msk, u8 local_id, u8 id)
770{
771 return local_id == id || (!local_id && msk->mpc_endpoint_id == id);
772}
773
774static void mptcp_pm_nl_rm_addr_or_subflow(struct mptcp_sock *msk,
775 const struct mptcp_rm_list *rm_list,
776 enum linux_mptcp_mib_field rm_type)
777{
778 struct mptcp_subflow_context *subflow, *tmp;
779 struct sock *sk = (struct sock *)msk;
780 u8 i;
781
782 pr_debug("%s rm_list_nr %d",
783 rm_type == MPTCP_MIB_RMADDR ? "address" : "subflow", rm_list->nr);
784
785 msk_owned_by_me(msk);
786
787 if (sk->sk_state == TCP_LISTEN)
788 return;
789
790 if (!rm_list->nr)
791 return;
792
793 if (list_empty(head: &msk->conn_list))
794 return;
795
796 for (i = 0; i < rm_list->nr; i++) {
797 u8 rm_id = rm_list->ids[i];
798 bool removed = false;
799
800 mptcp_for_each_subflow_safe(msk, subflow, tmp) {
801 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
802 int how = RCV_SHUTDOWN | SEND_SHUTDOWN;
803 u8 id = subflow->local_id;
804
805 if (rm_type == MPTCP_MIB_RMADDR && subflow->remote_id != rm_id)
806 continue;
807 if (rm_type == MPTCP_MIB_RMSUBFLOW && !mptcp_local_id_match(msk, local_id: id, id: rm_id))
808 continue;
809
810 pr_debug(" -> %s rm_list_ids[%d]=%u local_id=%u remote_id=%u mpc_id=%u",
811 rm_type == MPTCP_MIB_RMADDR ? "address" : "subflow",
812 i, rm_id, subflow->local_id, subflow->remote_id,
813 msk->mpc_endpoint_id);
814 spin_unlock_bh(lock: &msk->pm.lock);
815 mptcp_subflow_shutdown(sk, ssk, how);
816
817 /* the following takes care of updating the subflows counter */
818 mptcp_close_ssk(sk, ssk, subflow);
819 spin_lock_bh(lock: &msk->pm.lock);
820
821 removed = true;
822 __MPTCP_INC_STATS(net: sock_net(sk), field: rm_type);
823 }
824 if (rm_type == MPTCP_MIB_RMSUBFLOW)
825 __set_bit(rm_id ? rm_id : msk->mpc_endpoint_id, msk->pm.id_avail_bitmap);
826 if (!removed)
827 continue;
828
829 if (!mptcp_pm_is_kernel(msk))
830 continue;
831
832 if (rm_type == MPTCP_MIB_RMADDR) {
833 msk->pm.add_addr_accepted--;
834 WRITE_ONCE(msk->pm.accept_addr, true);
835 } else if (rm_type == MPTCP_MIB_RMSUBFLOW) {
836 msk->pm.local_addr_used--;
837 }
838 }
839}
840
841static void mptcp_pm_nl_rm_addr_received(struct mptcp_sock *msk)
842{
843 mptcp_pm_nl_rm_addr_or_subflow(msk, rm_list: &msk->pm.rm_list_rx, rm_type: MPTCP_MIB_RMADDR);
844}
845
846void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk,
847 const struct mptcp_rm_list *rm_list)
848{
849 mptcp_pm_nl_rm_addr_or_subflow(msk, rm_list, rm_type: MPTCP_MIB_RMSUBFLOW);
850}
851
852void mptcp_pm_nl_work(struct mptcp_sock *msk)
853{
854 struct mptcp_pm_data *pm = &msk->pm;
855
856 msk_owned_by_me(msk);
857
858 if (!(pm->status & MPTCP_PM_WORK_MASK))
859 return;
860
861 spin_lock_bh(lock: &msk->pm.lock);
862
863 pr_debug("msk=%p status=%x", msk, pm->status);
864 if (pm->status & BIT(MPTCP_PM_ADD_ADDR_RECEIVED)) {
865 pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_RECEIVED);
866 mptcp_pm_nl_add_addr_received(msk);
867 }
868 if (pm->status & BIT(MPTCP_PM_ADD_ADDR_SEND_ACK)) {
869 pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_SEND_ACK);
870 mptcp_pm_nl_addr_send_ack(msk);
871 }
872 if (pm->status & BIT(MPTCP_PM_RM_ADDR_RECEIVED)) {
873 pm->status &= ~BIT(MPTCP_PM_RM_ADDR_RECEIVED);
874 mptcp_pm_nl_rm_addr_received(msk);
875 }
876 if (pm->status & BIT(MPTCP_PM_ESTABLISHED)) {
877 pm->status &= ~BIT(MPTCP_PM_ESTABLISHED);
878 mptcp_pm_nl_fully_established(msk);
879 }
880 if (pm->status & BIT(MPTCP_PM_SUBFLOW_ESTABLISHED)) {
881 pm->status &= ~BIT(MPTCP_PM_SUBFLOW_ESTABLISHED);
882 mptcp_pm_nl_subflow_established(msk);
883 }
884
885 spin_unlock_bh(lock: &msk->pm.lock);
886}
887
888static bool address_use_port(struct mptcp_pm_addr_entry *entry)
889{
890 return (entry->flags &
891 (MPTCP_PM_ADDR_FLAG_SIGNAL | MPTCP_PM_ADDR_FLAG_SUBFLOW)) ==
892 MPTCP_PM_ADDR_FLAG_SIGNAL;
893}
894
895/* caller must ensure the RCU grace period is already elapsed */
896static void __mptcp_pm_release_addr_entry(struct mptcp_pm_addr_entry *entry)
897{
898 if (entry->lsk)
899 sock_release(sock: entry->lsk);
900 kfree(objp: entry);
901}
902
903static int mptcp_pm_nl_append_new_local_addr(struct pm_nl_pernet *pernet,
904 struct mptcp_pm_addr_entry *entry)
905{
906 struct mptcp_pm_addr_entry *cur, *del_entry = NULL;
907 unsigned int addr_max;
908 int ret = -EINVAL;
909
910 spin_lock_bh(lock: &pernet->lock);
911 /* to keep the code simple, don't do IDR-like allocation for address ID,
912 * just bail when we exceed limits
913 */
914 if (pernet->next_id == MPTCP_PM_MAX_ADDR_ID)
915 pernet->next_id = 1;
916 if (pernet->addrs >= MPTCP_PM_ADDR_MAX) {
917 ret = -ERANGE;
918 goto out;
919 }
920 if (test_bit(entry->addr.id, pernet->id_bitmap)) {
921 ret = -EBUSY;
922 goto out;
923 }
924
925 /* do not insert duplicate address, differentiate on port only
926 * singled addresses
927 */
928 if (!address_use_port(entry))
929 entry->addr.port = 0;
930 list_for_each_entry(cur, &pernet->local_addr_list, list) {
931 if (mptcp_addresses_equal(a: &cur->addr, b: &entry->addr,
932 use_port: cur->addr.port || entry->addr.port)) {
933 /* allow replacing the exiting endpoint only if such
934 * endpoint is an implicit one and the user-space
935 * did not provide an endpoint id
936 */
937 if (!(cur->flags & MPTCP_PM_ADDR_FLAG_IMPLICIT)) {
938 ret = -EEXIST;
939 goto out;
940 }
941 if (entry->addr.id)
942 goto out;
943
944 pernet->addrs--;
945 entry->addr.id = cur->addr.id;
946 list_del_rcu(entry: &cur->list);
947 del_entry = cur;
948 break;
949 }
950 }
951
952 if (!entry->addr.id) {
953find_next:
954 entry->addr.id = find_next_zero_bit(addr: pernet->id_bitmap,
955 MPTCP_PM_MAX_ADDR_ID + 1,
956 offset: pernet->next_id);
957 if (!entry->addr.id && pernet->next_id != 1) {
958 pernet->next_id = 1;
959 goto find_next;
960 }
961 }
962
963 if (!entry->addr.id)
964 goto out;
965
966 __set_bit(entry->addr.id, pernet->id_bitmap);
967 if (entry->addr.id > pernet->next_id)
968 pernet->next_id = entry->addr.id;
969
970 if (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL) {
971 addr_max = pernet->add_addr_signal_max;
972 WRITE_ONCE(pernet->add_addr_signal_max, addr_max + 1);
973 }
974 if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) {
975 addr_max = pernet->local_addr_max;
976 WRITE_ONCE(pernet->local_addr_max, addr_max + 1);
977 }
978
979 pernet->addrs++;
980 if (!entry->addr.port)
981 list_add_tail_rcu(new: &entry->list, head: &pernet->local_addr_list);
982 else
983 list_add_rcu(new: &entry->list, head: &pernet->local_addr_list);
984 ret = entry->addr.id;
985
986out:
987 spin_unlock_bh(lock: &pernet->lock);
988
989 /* just replaced an existing entry, free it */
990 if (del_entry) {
991 synchronize_rcu();
992 __mptcp_pm_release_addr_entry(entry: del_entry);
993 }
994 return ret;
995}
996
997static struct lock_class_key mptcp_slock_keys[2];
998static struct lock_class_key mptcp_keys[2];
999
1000static int mptcp_pm_nl_create_listen_socket(struct sock *sk,
1001 struct mptcp_pm_addr_entry *entry)
1002{
1003 bool is_ipv6 = sk->sk_family == AF_INET6;
1004 int addrlen = sizeof(struct sockaddr_in);
1005 struct sockaddr_storage addr;
1006 struct sock *newsk, *ssk;
1007 int backlog = 1024;
1008 int err;
1009
1010 err = sock_create_kern(net: sock_net(sk), family: entry->addr.family,
1011 type: SOCK_STREAM, IPPROTO_MPTCP, res: &entry->lsk);
1012 if (err)
1013 return err;
1014
1015 newsk = entry->lsk->sk;
1016 if (!newsk)
1017 return -EINVAL;
1018
1019 /* The subflow socket lock is acquired in a nested to the msk one
1020 * in several places, even by the TCP stack, and this msk is a kernel
1021 * socket: lockdep complains. Instead of propagating the _nested
1022 * modifiers in several places, re-init the lock class for the msk
1023 * socket to an mptcp specific one.
1024 */
1025 sock_lock_init_class_and_name(newsk,
1026 is_ipv6 ? "mlock-AF_INET6" : "mlock-AF_INET",
1027 &mptcp_slock_keys[is_ipv6],
1028 is_ipv6 ? "msk_lock-AF_INET6" : "msk_lock-AF_INET",
1029 &mptcp_keys[is_ipv6]);
1030
1031 lock_sock(sk: newsk);
1032 ssk = __mptcp_nmpc_sk(mptcp_sk(newsk));
1033 release_sock(sk: newsk);
1034 if (IS_ERR(ptr: ssk))
1035 return PTR_ERR(ptr: ssk);
1036
1037 mptcp_info2sockaddr(info: &entry->addr, addr: &addr, family: entry->addr.family);
1038#if IS_ENABLED(CONFIG_MPTCP_IPV6)
1039 if (entry->addr.family == AF_INET6)
1040 addrlen = sizeof(struct sockaddr_in6);
1041#endif
1042 if (ssk->sk_family == AF_INET)
1043 err = inet_bind_sk(sk: ssk, uaddr: (struct sockaddr *)&addr, addr_len: addrlen);
1044#if IS_ENABLED(CONFIG_MPTCP_IPV6)
1045 else if (ssk->sk_family == AF_INET6)
1046 err = inet6_bind_sk(sk: ssk, uaddr: (struct sockaddr *)&addr, addr_len: addrlen);
1047#endif
1048 if (err)
1049 return err;
1050
1051 inet_sk_state_store(sk: newsk, newstate: TCP_LISTEN);
1052 lock_sock(sk: ssk);
1053 err = __inet_listen_sk(sk: ssk, backlog);
1054 if (!err)
1055 mptcp_event_pm_listener(ssk, event: MPTCP_EVENT_LISTENER_CREATED);
1056 release_sock(sk: 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(a: &entry->addr, b: skc, use_port: 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(size: sizeof(*entry), GFP_ATOMIC);
1081 if (!entry)
1082 return -ENOMEM;
1083
1084 entry->addr = *skc;
1085 entry->addr.id = 0;
1086 entry->addr.port = 0;
1087 entry->ifindex = 0;
1088 entry->flags = MPTCP_PM_ADDR_FLAG_IMPLICIT;
1089 entry->lsk = NULL;
1090 ret = mptcp_pm_nl_append_new_local_addr(pernet, entry);
1091 if (ret < 0)
1092 kfree(objp: 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_UNS_ADMIN_PERM,
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(sk: 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(subflow: 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(sk: ssk);
1127 if (!tcp_rtx_and_write_queues_empty(sk: ssk)) {
1128 subflow->stale = 1;
1129 __mptcp_retransmit_pending_data(sk);
1130 MPTCP_INC_STATS(net, field: MPTCP_MIB_SUBFLOWSTALE);
1131 }
1132 unlock_sock_fast(sk: 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, flags: 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, nla: attr,
1168 policy: mptcp_pm_address_nl_policy, extack: info->extack);
1169 if (err)
1170 return err;
1171
1172 if (tb[MPTCP_PM_ADDR_ATTR_ID])
1173 addr->id = nla_get_u8(nla: 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(nla: 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(family: 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(nla: tb[addr_addr]);
1204 else
1205#endif
1206 addr->addr.s_addr = nla_get_in_addr(nla: 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, require_family: 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, addr: &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(nla: 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(nla: 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(net: 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_slot, s_num: &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(lock: &msk->pm.lock);
1271 mptcp_pm_create_subflow_or_signal_addr(msk);
1272 spin_unlock_bh(lock: &msk->pm.lock);
1273 release_sock(sk);
1274
1275next:
1276 sock_put(sk);
1277 cond_resched();
1278 }
1279
1280 return 0;
1281}
1282
1283int mptcp_pm_nl_add_addr_doit(struct sk_buff *skb, struct genl_info *info)
1284{
1285 struct nlattr *attr = info->attrs[MPTCP_PM_ENDPOINT_ADDR];
1286 struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
1287 struct mptcp_pm_addr_entry addr, *entry;
1288 int ret;
1289
1290 ret = mptcp_pm_parse_entry(attr, info, require_family: true, entry: &addr);
1291 if (ret < 0)
1292 return ret;
1293
1294 if (addr.addr.port && !(addr.flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) {
1295 GENL_SET_ERR_MSG(info, "flags must have signal when using port");
1296 return -EINVAL;
1297 }
1298
1299 if (addr.flags & MPTCP_PM_ADDR_FLAG_SIGNAL &&
1300 addr.flags & MPTCP_PM_ADDR_FLAG_FULLMESH) {
1301 GENL_SET_ERR_MSG(info, "flags mustn't have both signal and fullmesh");
1302 return -EINVAL;
1303 }
1304
1305 if (addr.flags & MPTCP_PM_ADDR_FLAG_IMPLICIT) {
1306 GENL_SET_ERR_MSG(info, "can't create IMPLICIT endpoint");
1307 return -EINVAL;
1308 }
1309
1310 entry = kzalloc(size: sizeof(*entry), GFP_KERNEL_ACCOUNT);
1311 if (!entry) {
1312 GENL_SET_ERR_MSG(info, "can't allocate addr");
1313 return -ENOMEM;
1314 }
1315
1316 *entry = addr;
1317 if (entry->addr.port) {
1318 ret = mptcp_pm_nl_create_listen_socket(sk: skb->sk, entry);
1319 if (ret) {
1320 GENL_SET_ERR_MSG_FMT(info, "create listen socket error: %d", ret);
1321 goto out_free;
1322 }
1323 }
1324 ret = mptcp_pm_nl_append_new_local_addr(pernet, entry);
1325 if (ret < 0) {
1326 GENL_SET_ERR_MSG_FMT(info, "too many addresses or duplicate one: %d", ret);
1327 goto out_free;
1328 }
1329
1330 mptcp_nl_add_subflow_or_signal_addr(net: sock_net(sk: skb->sk));
1331 return 0;
1332
1333out_free:
1334 __mptcp_pm_release_addr_entry(entry);
1335 return ret;
1336}
1337
1338int mptcp_pm_nl_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, unsigned int id,
1339 u8 *flags, int *ifindex)
1340{
1341 struct mptcp_pm_addr_entry *entry;
1342 struct sock *sk = (struct sock *)msk;
1343 struct net *net = sock_net(sk);
1344
1345 rcu_read_lock();
1346 entry = __lookup_addr_by_id(pernet: pm_nl_get_pernet(net), id);
1347 if (entry) {
1348 *flags = entry->flags;
1349 *ifindex = entry->ifindex;
1350 }
1351 rcu_read_unlock();
1352
1353 return 0;
1354}
1355
1356static bool remove_anno_list_by_saddr(struct mptcp_sock *msk,
1357 const struct mptcp_addr_info *addr)
1358{
1359 struct mptcp_pm_add_entry *entry;
1360
1361 entry = mptcp_pm_del_add_timer(msk, addr, check_id: false);
1362 if (entry) {
1363 list_del(entry: &entry->list);
1364 kfree(objp: entry);
1365 return true;
1366 }
1367
1368 return false;
1369}
1370
1371static bool mptcp_pm_remove_anno_addr(struct mptcp_sock *msk,
1372 const struct mptcp_addr_info *addr,
1373 bool force)
1374{
1375 struct mptcp_rm_list list = { .nr = 0 };
1376 bool ret;
1377
1378 list.ids[list.nr++] = addr->id;
1379
1380 ret = remove_anno_list_by_saddr(msk, addr);
1381 if (ret || force) {
1382 spin_lock_bh(lock: &msk->pm.lock);
1383 mptcp_pm_remove_addr(msk, rm_list: &list);
1384 spin_unlock_bh(lock: &msk->pm.lock);
1385 }
1386 return ret;
1387}
1388
1389static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net,
1390 const struct mptcp_pm_addr_entry *entry)
1391{
1392 const struct mptcp_addr_info *addr = &entry->addr;
1393 struct mptcp_rm_list list = { .nr = 0 };
1394 long s_slot = 0, s_num = 0;
1395 struct mptcp_sock *msk;
1396
1397 pr_debug("remove_id=%d", addr->id);
1398
1399 list.ids[list.nr++] = addr->id;
1400
1401 while ((msk = mptcp_token_iter_next(net, s_slot: &s_slot, s_num: &s_num)) != NULL) {
1402 struct sock *sk = (struct sock *)msk;
1403 bool remove_subflow;
1404
1405 if (mptcp_pm_is_userspace(msk))
1406 goto next;
1407
1408 if (list_empty(head: &msk->conn_list)) {
1409 mptcp_pm_remove_anno_addr(msk, addr, force: false);
1410 goto next;
1411 }
1412
1413 lock_sock(sk);
1414 remove_subflow = lookup_subflow_by_saddr(list: &msk->conn_list, saddr: addr);
1415 mptcp_pm_remove_anno_addr(msk, addr, force: remove_subflow &&
1416 !(entry->flags & MPTCP_PM_ADDR_FLAG_IMPLICIT));
1417 if (remove_subflow)
1418 mptcp_pm_remove_subflow(msk, rm_list: &list);
1419 release_sock(sk);
1420
1421next:
1422 sock_put(sk);
1423 cond_resched();
1424 }
1425
1426 return 0;
1427}
1428
1429static int mptcp_nl_remove_id_zero_address(struct net *net,
1430 struct mptcp_addr_info *addr)
1431{
1432 struct mptcp_rm_list list = { .nr = 0 };
1433 long s_slot = 0, s_num = 0;
1434 struct mptcp_sock *msk;
1435
1436 list.ids[list.nr++] = 0;
1437
1438 while ((msk = mptcp_token_iter_next(net, s_slot: &s_slot, s_num: &s_num)) != NULL) {
1439 struct sock *sk = (struct sock *)msk;
1440 struct mptcp_addr_info msk_local;
1441
1442 if (list_empty(head: &msk->conn_list) || mptcp_pm_is_userspace(msk))
1443 goto next;
1444
1445 mptcp_local_address(skc: (struct sock_common *)msk, addr: &msk_local);
1446 if (!mptcp_addresses_equal(a: &msk_local, b: addr, use_port: addr->port))
1447 goto next;
1448
1449 lock_sock(sk);
1450 spin_lock_bh(lock: &msk->pm.lock);
1451 mptcp_pm_remove_addr(msk, rm_list: &list);
1452 mptcp_pm_nl_rm_subflow_received(msk, rm_list: &list);
1453 spin_unlock_bh(lock: &msk->pm.lock);
1454 release_sock(sk);
1455
1456next:
1457 sock_put(sk);
1458 cond_resched();
1459 }
1460
1461 return 0;
1462}
1463
1464int mptcp_pm_nl_del_addr_doit(struct sk_buff *skb, struct genl_info *info)
1465{
1466 struct nlattr *attr = info->attrs[MPTCP_PM_ENDPOINT_ADDR];
1467 struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
1468 struct mptcp_pm_addr_entry addr, *entry;
1469 unsigned int addr_max;
1470 int ret;
1471
1472 ret = mptcp_pm_parse_entry(attr, info, require_family: false, entry: &addr);
1473 if (ret < 0)
1474 return ret;
1475
1476 /* the zero id address is special: the first address used by the msk
1477 * always gets such an id, so different subflows can have different zero
1478 * id addresses. Additionally zero id is not accounted for in id_bitmap.
1479 * Let's use an 'mptcp_rm_list' instead of the common remove code.
1480 */
1481 if (addr.addr.id == 0)
1482 return mptcp_nl_remove_id_zero_address(net: sock_net(sk: skb->sk), addr: &addr.addr);
1483
1484 spin_lock_bh(lock: &pernet->lock);
1485 entry = __lookup_addr_by_id(pernet, id: addr.addr.id);
1486 if (!entry) {
1487 GENL_SET_ERR_MSG(info, "address not found");
1488 spin_unlock_bh(lock: &pernet->lock);
1489 return -EINVAL;
1490 }
1491 if (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL) {
1492 addr_max = pernet->add_addr_signal_max;
1493 WRITE_ONCE(pernet->add_addr_signal_max, addr_max - 1);
1494 }
1495 if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) {
1496 addr_max = pernet->local_addr_max;
1497 WRITE_ONCE(pernet->local_addr_max, addr_max - 1);
1498 }
1499
1500 pernet->addrs--;
1501 list_del_rcu(entry: &entry->list);
1502 __clear_bit(entry->addr.id, pernet->id_bitmap);
1503 spin_unlock_bh(lock: &pernet->lock);
1504
1505 mptcp_nl_remove_subflow_and_signal_addr(net: sock_net(sk: skb->sk), entry);
1506 synchronize_rcu();
1507 __mptcp_pm_release_addr_entry(entry);
1508
1509 return ret;
1510}
1511
1512void mptcp_pm_remove_addrs(struct mptcp_sock *msk, struct list_head *rm_list)
1513{
1514 struct mptcp_rm_list alist = { .nr = 0 };
1515 struct mptcp_pm_addr_entry *entry;
1516
1517 list_for_each_entry(entry, rm_list, list) {
1518 remove_anno_list_by_saddr(msk, addr: &entry->addr);
1519 if (alist.nr < MPTCP_RM_IDS_MAX)
1520 alist.ids[alist.nr++] = entry->addr.id;
1521 }
1522
1523 if (alist.nr) {
1524 spin_lock_bh(lock: &msk->pm.lock);
1525 mptcp_pm_remove_addr(msk, rm_list: &alist);
1526 spin_unlock_bh(lock: &msk->pm.lock);
1527 }
1528}
1529
1530void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk,
1531 struct list_head *rm_list)
1532{
1533 struct mptcp_rm_list alist = { .nr = 0 }, slist = { .nr = 0 };
1534 struct mptcp_pm_addr_entry *entry;
1535
1536 list_for_each_entry(entry, rm_list, list) {
1537 if (lookup_subflow_by_saddr(list: &msk->conn_list, saddr: &entry->addr) &&
1538 slist.nr < MPTCP_RM_IDS_MAX)
1539 slist.ids[slist.nr++] = entry->addr.id;
1540
1541 if (remove_anno_list_by_saddr(msk, addr: &entry->addr) &&
1542 alist.nr < MPTCP_RM_IDS_MAX)
1543 alist.ids[alist.nr++] = entry->addr.id;
1544 }
1545
1546 if (alist.nr) {
1547 spin_lock_bh(lock: &msk->pm.lock);
1548 mptcp_pm_remove_addr(msk, rm_list: &alist);
1549 spin_unlock_bh(lock: &msk->pm.lock);
1550 }
1551 if (slist.nr)
1552 mptcp_pm_remove_subflow(msk, rm_list: &slist);
1553}
1554
1555static void mptcp_nl_remove_addrs_list(struct net *net,
1556 struct list_head *rm_list)
1557{
1558 long s_slot = 0, s_num = 0;
1559 struct mptcp_sock *msk;
1560
1561 if (list_empty(head: rm_list))
1562 return;
1563
1564 while ((msk = mptcp_token_iter_next(net, s_slot: &s_slot, s_num: &s_num)) != NULL) {
1565 struct sock *sk = (struct sock *)msk;
1566
1567 if (!mptcp_pm_is_userspace(msk)) {
1568 lock_sock(sk);
1569 mptcp_pm_remove_addrs_and_subflows(msk, rm_list);
1570 release_sock(sk);
1571 }
1572
1573 sock_put(sk);
1574 cond_resched();
1575 }
1576}
1577
1578/* caller must ensure the RCU grace period is already elapsed */
1579static void __flush_addrs(struct list_head *list)
1580{
1581 while (!list_empty(head: list)) {
1582 struct mptcp_pm_addr_entry *cur;
1583
1584 cur = list_entry(list->next,
1585 struct mptcp_pm_addr_entry, list);
1586 list_del_rcu(entry: &cur->list);
1587 __mptcp_pm_release_addr_entry(entry: cur);
1588 }
1589}
1590
1591static void __reset_counters(struct pm_nl_pernet *pernet)
1592{
1593 WRITE_ONCE(pernet->add_addr_signal_max, 0);
1594 WRITE_ONCE(pernet->add_addr_accept_max, 0);
1595 WRITE_ONCE(pernet->local_addr_max, 0);
1596 pernet->addrs = 0;
1597}
1598
1599int mptcp_pm_nl_flush_addrs_doit(struct sk_buff *skb, struct genl_info *info)
1600{
1601 struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
1602 LIST_HEAD(free_list);
1603
1604 spin_lock_bh(lock: &pernet->lock);
1605 list_splice_init(list: &pernet->local_addr_list, head: &free_list);
1606 __reset_counters(pernet);
1607 pernet->next_id = 1;
1608 bitmap_zero(dst: pernet->id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1);
1609 spin_unlock_bh(lock: &pernet->lock);
1610 mptcp_nl_remove_addrs_list(net: sock_net(sk: skb->sk), rm_list: &free_list);
1611 synchronize_rcu();
1612 __flush_addrs(list: &free_list);
1613 return 0;
1614}
1615
1616static int mptcp_nl_fill_addr(struct sk_buff *skb,
1617 struct mptcp_pm_addr_entry *entry)
1618{
1619 struct mptcp_addr_info *addr = &entry->addr;
1620 struct nlattr *attr;
1621
1622 attr = nla_nest_start(skb, attrtype: MPTCP_PM_ATTR_ADDR);
1623 if (!attr)
1624 return -EMSGSIZE;
1625
1626 if (nla_put_u16(skb, attrtype: MPTCP_PM_ADDR_ATTR_FAMILY, value: addr->family))
1627 goto nla_put_failure;
1628 if (nla_put_u16(skb, attrtype: MPTCP_PM_ADDR_ATTR_PORT, ntohs(addr->port)))
1629 goto nla_put_failure;
1630 if (nla_put_u8(skb, attrtype: MPTCP_PM_ADDR_ATTR_ID, value: addr->id))
1631 goto nla_put_failure;
1632 if (nla_put_u32(skb, attrtype: MPTCP_PM_ADDR_ATTR_FLAGS, value: entry->flags))
1633 goto nla_put_failure;
1634 if (entry->ifindex &&
1635 nla_put_s32(skb, attrtype: MPTCP_PM_ADDR_ATTR_IF_IDX, value: entry->ifindex))
1636 goto nla_put_failure;
1637
1638 if (addr->family == AF_INET &&
1639 nla_put_in_addr(skb, attrtype: MPTCP_PM_ADDR_ATTR_ADDR4,
1640 addr: addr->addr.s_addr))
1641 goto nla_put_failure;
1642#if IS_ENABLED(CONFIG_MPTCP_IPV6)
1643 else if (addr->family == AF_INET6 &&
1644 nla_put_in6_addr(skb, attrtype: MPTCP_PM_ADDR_ATTR_ADDR6, addr: &addr->addr6))
1645 goto nla_put_failure;
1646#endif
1647 nla_nest_end(skb, start: attr);
1648 return 0;
1649
1650nla_put_failure:
1651 nla_nest_cancel(skb, start: attr);
1652 return -EMSGSIZE;
1653}
1654
1655int mptcp_pm_nl_get_addr_doit(struct sk_buff *skb, struct genl_info *info)
1656{
1657 struct nlattr *attr = info->attrs[MPTCP_PM_ENDPOINT_ADDR];
1658 struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
1659 struct mptcp_pm_addr_entry addr, *entry;
1660 struct sk_buff *msg;
1661 void *reply;
1662 int ret;
1663
1664 ret = mptcp_pm_parse_entry(attr, info, require_family: false, entry: &addr);
1665 if (ret < 0)
1666 return ret;
1667
1668 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1669 if (!msg)
1670 return -ENOMEM;
1671
1672 reply = genlmsg_put_reply(skb: msg, info, family: &mptcp_genl_family, flags: 0,
1673 cmd: info->genlhdr->cmd);
1674 if (!reply) {
1675 GENL_SET_ERR_MSG(info, "not enough space in Netlink message");
1676 ret = -EMSGSIZE;
1677 goto fail;
1678 }
1679
1680 spin_lock_bh(lock: &pernet->lock);
1681 entry = __lookup_addr_by_id(pernet, id: addr.addr.id);
1682 if (!entry) {
1683 GENL_SET_ERR_MSG(info, "address not found");
1684 ret = -EINVAL;
1685 goto unlock_fail;
1686 }
1687
1688 ret = mptcp_nl_fill_addr(skb: msg, entry);
1689 if (ret)
1690 goto unlock_fail;
1691
1692 genlmsg_end(skb: msg, hdr: reply);
1693 ret = genlmsg_reply(skb: msg, info);
1694 spin_unlock_bh(lock: &pernet->lock);
1695 return ret;
1696
1697unlock_fail:
1698 spin_unlock_bh(lock: &pernet->lock);
1699
1700fail:
1701 nlmsg_free(skb: msg);
1702 return ret;
1703}
1704
1705int mptcp_pm_nl_get_addr_dumpit(struct sk_buff *msg,
1706 struct netlink_callback *cb)
1707{
1708 struct net *net = sock_net(sk: msg->sk);
1709 struct mptcp_pm_addr_entry *entry;
1710 struct pm_nl_pernet *pernet;
1711 int id = cb->args[0];
1712 void *hdr;
1713 int i;
1714
1715 pernet = pm_nl_get_pernet(net);
1716
1717 spin_lock_bh(lock: &pernet->lock);
1718 for (i = id; i < MPTCP_PM_MAX_ADDR_ID + 1; i++) {
1719 if (test_bit(i, pernet->id_bitmap)) {
1720 entry = __lookup_addr_by_id(pernet, id: i);
1721 if (!entry)
1722 break;
1723
1724 if (entry->addr.id <= id)
1725 continue;
1726
1727 hdr = genlmsg_put(skb: msg, NETLINK_CB(cb->skb).portid,
1728 seq: cb->nlh->nlmsg_seq, family: &mptcp_genl_family,
1729 NLM_F_MULTI, cmd: MPTCP_PM_CMD_GET_ADDR);
1730 if (!hdr)
1731 break;
1732
1733 if (mptcp_nl_fill_addr(skb: msg, entry) < 0) {
1734 genlmsg_cancel(skb: msg, hdr);
1735 break;
1736 }
1737
1738 id = entry->addr.id;
1739 genlmsg_end(skb: msg, hdr);
1740 }
1741 }
1742 spin_unlock_bh(lock: &pernet->lock);
1743
1744 cb->args[0] = id;
1745 return msg->len;
1746}
1747
1748static int parse_limit(struct genl_info *info, int id, unsigned int *limit)
1749{
1750 struct nlattr *attr = info->attrs[id];
1751
1752 if (!attr)
1753 return 0;
1754
1755 *limit = nla_get_u32(nla: attr);
1756 if (*limit > MPTCP_PM_ADDR_MAX) {
1757 GENL_SET_ERR_MSG(info, "limit greater than maximum");
1758 return -EINVAL;
1759 }
1760 return 0;
1761}
1762
1763int mptcp_pm_nl_set_limits_doit(struct sk_buff *skb, struct genl_info *info)
1764{
1765 struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
1766 unsigned int rcv_addrs, subflows;
1767 int ret;
1768
1769 spin_lock_bh(lock: &pernet->lock);
1770 rcv_addrs = pernet->add_addr_accept_max;
1771 ret = parse_limit(info, id: MPTCP_PM_ATTR_RCV_ADD_ADDRS, limit: &rcv_addrs);
1772 if (ret)
1773 goto unlock;
1774
1775 subflows = pernet->subflows_max;
1776 ret = parse_limit(info, id: MPTCP_PM_ATTR_SUBFLOWS, limit: &subflows);
1777 if (ret)
1778 goto unlock;
1779
1780 WRITE_ONCE(pernet->add_addr_accept_max, rcv_addrs);
1781 WRITE_ONCE(pernet->subflows_max, subflows);
1782
1783unlock:
1784 spin_unlock_bh(lock: &pernet->lock);
1785 return ret;
1786}
1787
1788int mptcp_pm_nl_get_limits_doit(struct sk_buff *skb, struct genl_info *info)
1789{
1790 struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
1791 struct sk_buff *msg;
1792 void *reply;
1793
1794 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1795 if (!msg)
1796 return -ENOMEM;
1797
1798 reply = genlmsg_put_reply(skb: msg, info, family: &mptcp_genl_family, flags: 0,
1799 cmd: MPTCP_PM_CMD_GET_LIMITS);
1800 if (!reply)
1801 goto fail;
1802
1803 if (nla_put_u32(skb: msg, attrtype: MPTCP_PM_ATTR_RCV_ADD_ADDRS,
1804 READ_ONCE(pernet->add_addr_accept_max)))
1805 goto fail;
1806
1807 if (nla_put_u32(skb: msg, attrtype: MPTCP_PM_ATTR_SUBFLOWS,
1808 READ_ONCE(pernet->subflows_max)))
1809 goto fail;
1810
1811 genlmsg_end(skb: msg, hdr: reply);
1812 return genlmsg_reply(skb: msg, info);
1813
1814fail:
1815 GENL_SET_ERR_MSG(info, "not enough space in Netlink message");
1816 nlmsg_free(skb: msg);
1817 return -EMSGSIZE;
1818}
1819
1820static void mptcp_pm_nl_fullmesh(struct mptcp_sock *msk,
1821 struct mptcp_addr_info *addr)
1822{
1823 struct mptcp_rm_list list = { .nr = 0 };
1824
1825 list.ids[list.nr++] = addr->id;
1826
1827 spin_lock_bh(lock: &msk->pm.lock);
1828 mptcp_pm_nl_rm_subflow_received(msk, rm_list: &list);
1829 mptcp_pm_create_subflow_or_signal_addr(msk);
1830 spin_unlock_bh(lock: &msk->pm.lock);
1831}
1832
1833static int mptcp_nl_set_flags(struct net *net,
1834 struct mptcp_addr_info *addr,
1835 u8 bkup, u8 changed)
1836{
1837 long s_slot = 0, s_num = 0;
1838 struct mptcp_sock *msk;
1839 int ret = -EINVAL;
1840
1841 while ((msk = mptcp_token_iter_next(net, s_slot: &s_slot, s_num: &s_num)) != NULL) {
1842 struct sock *sk = (struct sock *)msk;
1843
1844 if (list_empty(head: &msk->conn_list) || mptcp_pm_is_userspace(msk))
1845 goto next;
1846
1847 lock_sock(sk);
1848 if (changed & MPTCP_PM_ADDR_FLAG_BACKUP)
1849 ret = mptcp_pm_nl_mp_prio_send_ack(msk, addr, NULL, bkup);
1850 if (changed & MPTCP_PM_ADDR_FLAG_FULLMESH)
1851 mptcp_pm_nl_fullmesh(msk, addr);
1852 release_sock(sk);
1853
1854next:
1855 sock_put(sk);
1856 cond_resched();
1857 }
1858
1859 return ret;
1860}
1861
1862int mptcp_pm_nl_set_flags(struct net *net, struct mptcp_pm_addr_entry *addr, u8 bkup)
1863{
1864 struct pm_nl_pernet *pernet = pm_nl_get_pernet(net);
1865 u8 changed, mask = MPTCP_PM_ADDR_FLAG_BACKUP |
1866 MPTCP_PM_ADDR_FLAG_FULLMESH;
1867 struct mptcp_pm_addr_entry *entry;
1868 u8 lookup_by_id = 0;
1869
1870 if (addr->addr.family == AF_UNSPEC) {
1871 lookup_by_id = 1;
1872 if (!addr->addr.id)
1873 return -EOPNOTSUPP;
1874 }
1875
1876 spin_lock_bh(lock: &pernet->lock);
1877 entry = __lookup_addr(pernet, info: &addr->addr, lookup_by_id);
1878 if (!entry) {
1879 spin_unlock_bh(lock: &pernet->lock);
1880 return -EINVAL;
1881 }
1882 if ((addr->flags & MPTCP_PM_ADDR_FLAG_FULLMESH) &&
1883 (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) {
1884 spin_unlock_bh(lock: &pernet->lock);
1885 return -EINVAL;
1886 }
1887
1888 changed = (addr->flags ^ entry->flags) & mask;
1889 entry->flags = (entry->flags & ~mask) | (addr->flags & mask);
1890 *addr = *entry;
1891 spin_unlock_bh(lock: &pernet->lock);
1892
1893 mptcp_nl_set_flags(net, addr: &addr->addr, bkup, changed);
1894 return 0;
1895}
1896
1897int mptcp_pm_nl_set_flags_doit(struct sk_buff *skb, struct genl_info *info)
1898{
1899 struct mptcp_pm_addr_entry remote = { .addr = { .family = AF_UNSPEC }, };
1900 struct mptcp_pm_addr_entry addr = { .addr = { .family = AF_UNSPEC }, };
1901 struct nlattr *attr_rem = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE];
1902 struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN];
1903 struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR];
1904 struct net *net = sock_net(sk: skb->sk);
1905 u8 bkup = 0;
1906 int ret;
1907
1908 ret = mptcp_pm_parse_entry(attr, info, require_family: false, entry: &addr);
1909 if (ret < 0)
1910 return ret;
1911
1912 if (attr_rem) {
1913 ret = mptcp_pm_parse_entry(attr: attr_rem, info, require_family: false, entry: &remote);
1914 if (ret < 0)
1915 return ret;
1916 }
1917
1918 if (addr.flags & MPTCP_PM_ADDR_FLAG_BACKUP)
1919 bkup = 1;
1920
1921 return mptcp_pm_set_flags(net, token, loc: &addr, rem: &remote, bkup);
1922}
1923
1924static void mptcp_nl_mcast_send(struct net *net, struct sk_buff *nlskb, gfp_t gfp)
1925{
1926 genlmsg_multicast_netns(family: &mptcp_genl_family, net,
1927 skb: nlskb, portid: 0, MPTCP_PM_EV_GRP_OFFSET, flags: gfp);
1928}
1929
1930bool mptcp_userspace_pm_active(const struct mptcp_sock *msk)
1931{
1932 return genl_has_listeners(family: &mptcp_genl_family,
1933 net: sock_net(sk: (const struct sock *)msk),
1934 MPTCP_PM_EV_GRP_OFFSET);
1935}
1936
1937static int mptcp_event_add_subflow(struct sk_buff *skb, const struct sock *ssk)
1938{
1939 const struct inet_sock *issk = inet_sk(ssk);
1940 const struct mptcp_subflow_context *sf;
1941
1942 if (nla_put_u16(skb, attrtype: MPTCP_ATTR_FAMILY, value: ssk->sk_family))
1943 return -EMSGSIZE;
1944
1945 switch (ssk->sk_family) {
1946 case AF_INET:
1947 if (nla_put_in_addr(skb, attrtype: MPTCP_ATTR_SADDR4, addr: issk->inet_saddr))
1948 return -EMSGSIZE;
1949 if (nla_put_in_addr(skb, attrtype: MPTCP_ATTR_DADDR4, addr: issk->inet_daddr))
1950 return -EMSGSIZE;
1951 break;
1952#if IS_ENABLED(CONFIG_MPTCP_IPV6)
1953 case AF_INET6: {
1954 const struct ipv6_pinfo *np = inet6_sk(sk: ssk);
1955
1956 if (nla_put_in6_addr(skb, attrtype: MPTCP_ATTR_SADDR6, addr: &np->saddr))
1957 return -EMSGSIZE;
1958 if (nla_put_in6_addr(skb, attrtype: MPTCP_ATTR_DADDR6, addr: &ssk->sk_v6_daddr))
1959 return -EMSGSIZE;
1960 break;
1961 }
1962#endif
1963 default:
1964 WARN_ON_ONCE(1);
1965 return -EMSGSIZE;
1966 }
1967
1968 if (nla_put_be16(skb, attrtype: MPTCP_ATTR_SPORT, value: issk->inet_sport))
1969 return -EMSGSIZE;
1970 if (nla_put_be16(skb, attrtype: MPTCP_ATTR_DPORT, value: issk->inet_dport))
1971 return -EMSGSIZE;
1972
1973 sf = mptcp_subflow_ctx(sk: ssk);
1974 if (WARN_ON_ONCE(!sf))
1975 return -EINVAL;
1976
1977 if (nla_put_u8(skb, attrtype: MPTCP_ATTR_LOC_ID, value: sf->local_id))
1978 return -EMSGSIZE;
1979
1980 if (nla_put_u8(skb, attrtype: MPTCP_ATTR_REM_ID, value: sf->remote_id))
1981 return -EMSGSIZE;
1982
1983 return 0;
1984}
1985
1986static int mptcp_event_put_token_and_ssk(struct sk_buff *skb,
1987 const struct mptcp_sock *msk,
1988 const struct sock *ssk)
1989{
1990 const struct sock *sk = (const struct sock *)msk;
1991 const struct mptcp_subflow_context *sf;
1992 u8 sk_err;
1993
1994 if (nla_put_u32(skb, attrtype: MPTCP_ATTR_TOKEN, value: msk->token))
1995 return -EMSGSIZE;
1996
1997 if (mptcp_event_add_subflow(skb, ssk))
1998 return -EMSGSIZE;
1999
2000 sf = mptcp_subflow_ctx(sk: ssk);
2001 if (WARN_ON_ONCE(!sf))
2002 return -EINVAL;
2003
2004 if (nla_put_u8(skb, attrtype: MPTCP_ATTR_BACKUP, value: sf->backup))
2005 return -EMSGSIZE;
2006
2007 if (ssk->sk_bound_dev_if &&
2008 nla_put_s32(skb, attrtype: MPTCP_ATTR_IF_IDX, value: ssk->sk_bound_dev_if))
2009 return -EMSGSIZE;
2010
2011 sk_err = READ_ONCE(ssk->sk_err);
2012 if (sk_err && sk->sk_state == TCP_ESTABLISHED &&
2013 nla_put_u8(skb, attrtype: MPTCP_ATTR_ERROR, value: sk_err))
2014 return -EMSGSIZE;
2015
2016 return 0;
2017}
2018
2019static int mptcp_event_sub_established(struct sk_buff *skb,
2020 const struct mptcp_sock *msk,
2021 const struct sock *ssk)
2022{
2023 return mptcp_event_put_token_and_ssk(skb, msk, ssk);
2024}
2025
2026static int mptcp_event_sub_closed(struct sk_buff *skb,
2027 const struct mptcp_sock *msk,
2028 const struct sock *ssk)
2029{
2030 const struct mptcp_subflow_context *sf;
2031
2032 if (mptcp_event_put_token_and_ssk(skb, msk, ssk))
2033 return -EMSGSIZE;
2034
2035 sf = mptcp_subflow_ctx(sk: ssk);
2036 if (!sf->reset_seen)
2037 return 0;
2038
2039 if (nla_put_u32(skb, attrtype: MPTCP_ATTR_RESET_REASON, value: sf->reset_reason))
2040 return -EMSGSIZE;
2041
2042 if (nla_put_u32(skb, attrtype: MPTCP_ATTR_RESET_FLAGS, value: sf->reset_transient))
2043 return -EMSGSIZE;
2044
2045 return 0;
2046}
2047
2048static int mptcp_event_created(struct sk_buff *skb,
2049 const struct mptcp_sock *msk,
2050 const struct sock *ssk)
2051{
2052 int err = nla_put_u32(skb, attrtype: MPTCP_ATTR_TOKEN, value: msk->token);
2053
2054 if (err)
2055 return err;
2056
2057 if (nla_put_u8(skb, attrtype: MPTCP_ATTR_SERVER_SIDE, READ_ONCE(msk->pm.server_side)))
2058 return -EMSGSIZE;
2059
2060 return mptcp_event_add_subflow(skb, ssk);
2061}
2062
2063void mptcp_event_addr_removed(const struct mptcp_sock *msk, uint8_t id)
2064{
2065 struct net *net = sock_net(sk: (const struct sock *)msk);
2066 struct nlmsghdr *nlh;
2067 struct sk_buff *skb;
2068
2069 if (!genl_has_listeners(family: &mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET))
2070 return;
2071
2072 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
2073 if (!skb)
2074 return;
2075
2076 nlh = genlmsg_put(skb, portid: 0, seq: 0, family: &mptcp_genl_family, flags: 0, cmd: MPTCP_EVENT_REMOVED);
2077 if (!nlh)
2078 goto nla_put_failure;
2079
2080 if (nla_put_u32(skb, attrtype: MPTCP_ATTR_TOKEN, value: msk->token))
2081 goto nla_put_failure;
2082
2083 if (nla_put_u8(skb, attrtype: MPTCP_ATTR_REM_ID, value: id))
2084 goto nla_put_failure;
2085
2086 genlmsg_end(skb, hdr: nlh);
2087 mptcp_nl_mcast_send(net, nlskb: skb, GFP_ATOMIC);
2088 return;
2089
2090nla_put_failure:
2091 nlmsg_free(skb);
2092}
2093
2094void mptcp_event_addr_announced(const struct sock *ssk,
2095 const struct mptcp_addr_info *info)
2096{
2097 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk: ssk);
2098 struct mptcp_sock *msk = mptcp_sk(subflow->conn);
2099 struct net *net = sock_net(sk: ssk);
2100 struct nlmsghdr *nlh;
2101 struct sk_buff *skb;
2102
2103 if (!genl_has_listeners(family: &mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET))
2104 return;
2105
2106 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
2107 if (!skb)
2108 return;
2109
2110 nlh = genlmsg_put(skb, portid: 0, seq: 0, family: &mptcp_genl_family, flags: 0,
2111 cmd: MPTCP_EVENT_ANNOUNCED);
2112 if (!nlh)
2113 goto nla_put_failure;
2114
2115 if (nla_put_u32(skb, attrtype: MPTCP_ATTR_TOKEN, value: msk->token))
2116 goto nla_put_failure;
2117
2118 if (nla_put_u8(skb, attrtype: MPTCP_ATTR_REM_ID, value: info->id))
2119 goto nla_put_failure;
2120
2121 if (nla_put_be16(skb, attrtype: MPTCP_ATTR_DPORT,
2122 value: info->port == 0 ?
2123 inet_sk(ssk)->inet_dport :
2124 info->port))
2125 goto nla_put_failure;
2126
2127 switch (info->family) {
2128 case AF_INET:
2129 if (nla_put_in_addr(skb, attrtype: MPTCP_ATTR_DADDR4, addr: info->addr.s_addr))
2130 goto nla_put_failure;
2131 break;
2132#if IS_ENABLED(CONFIG_MPTCP_IPV6)
2133 case AF_INET6:
2134 if (nla_put_in6_addr(skb, attrtype: MPTCP_ATTR_DADDR6, addr: &info->addr6))
2135 goto nla_put_failure;
2136 break;
2137#endif
2138 default:
2139 WARN_ON_ONCE(1);
2140 goto nla_put_failure;
2141 }
2142
2143 genlmsg_end(skb, hdr: nlh);
2144 mptcp_nl_mcast_send(net, nlskb: skb, GFP_ATOMIC);
2145 return;
2146
2147nla_put_failure:
2148 nlmsg_free(skb);
2149}
2150
2151void mptcp_event_pm_listener(const struct sock *ssk,
2152 enum mptcp_event_type event)
2153{
2154 const struct inet_sock *issk = inet_sk(ssk);
2155 struct net *net = sock_net(sk: ssk);
2156 struct nlmsghdr *nlh;
2157 struct sk_buff *skb;
2158
2159 if (!genl_has_listeners(family: &mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET))
2160 return;
2161
2162 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
2163 if (!skb)
2164 return;
2165
2166 nlh = genlmsg_put(skb, portid: 0, seq: 0, family: &mptcp_genl_family, flags: 0, cmd: event);
2167 if (!nlh)
2168 goto nla_put_failure;
2169
2170 if (nla_put_u16(skb, attrtype: MPTCP_ATTR_FAMILY, value: ssk->sk_family))
2171 goto nla_put_failure;
2172
2173 if (nla_put_be16(skb, attrtype: MPTCP_ATTR_SPORT, value: issk->inet_sport))
2174 goto nla_put_failure;
2175
2176 switch (ssk->sk_family) {
2177 case AF_INET:
2178 if (nla_put_in_addr(skb, attrtype: MPTCP_ATTR_SADDR4, addr: issk->inet_saddr))
2179 goto nla_put_failure;
2180 break;
2181#if IS_ENABLED(CONFIG_MPTCP_IPV6)
2182 case AF_INET6: {
2183 const struct ipv6_pinfo *np = inet6_sk(sk: ssk);
2184
2185 if (nla_put_in6_addr(skb, attrtype: MPTCP_ATTR_SADDR6, addr: &np->saddr))
2186 goto nla_put_failure;
2187 break;
2188 }
2189#endif
2190 default:
2191 WARN_ON_ONCE(1);
2192 goto nla_put_failure;
2193 }
2194
2195 genlmsg_end(skb, hdr: nlh);
2196 mptcp_nl_mcast_send(net, nlskb: skb, GFP_KERNEL);
2197 return;
2198
2199nla_put_failure:
2200 nlmsg_free(skb);
2201}
2202
2203void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk,
2204 const struct sock *ssk, gfp_t gfp)
2205{
2206 struct net *net = sock_net(sk: (const struct sock *)msk);
2207 struct nlmsghdr *nlh;
2208 struct sk_buff *skb;
2209
2210 if (!genl_has_listeners(family: &mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET))
2211 return;
2212
2213 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, flags: gfp);
2214 if (!skb)
2215 return;
2216
2217 nlh = genlmsg_put(skb, portid: 0, seq: 0, family: &mptcp_genl_family, flags: 0, cmd: type);
2218 if (!nlh)
2219 goto nla_put_failure;
2220
2221 switch (type) {
2222 case MPTCP_EVENT_UNSPEC:
2223 WARN_ON_ONCE(1);
2224 break;
2225 case MPTCP_EVENT_CREATED:
2226 case MPTCP_EVENT_ESTABLISHED:
2227 if (mptcp_event_created(skb, msk, ssk) < 0)
2228 goto nla_put_failure;
2229 break;
2230 case MPTCP_EVENT_CLOSED:
2231 if (nla_put_u32(skb, attrtype: MPTCP_ATTR_TOKEN, value: msk->token) < 0)
2232 goto nla_put_failure;
2233 break;
2234 case MPTCP_EVENT_ANNOUNCED:
2235 case MPTCP_EVENT_REMOVED:
2236 /* call mptcp_event_addr_announced()/removed instead */
2237 WARN_ON_ONCE(1);
2238 break;
2239 case MPTCP_EVENT_SUB_ESTABLISHED:
2240 case MPTCP_EVENT_SUB_PRIORITY:
2241 if (mptcp_event_sub_established(skb, msk, ssk) < 0)
2242 goto nla_put_failure;
2243 break;
2244 case MPTCP_EVENT_SUB_CLOSED:
2245 if (mptcp_event_sub_closed(skb, msk, ssk) < 0)
2246 goto nla_put_failure;
2247 break;
2248 case MPTCP_EVENT_LISTENER_CREATED:
2249 case MPTCP_EVENT_LISTENER_CLOSED:
2250 break;
2251 }
2252
2253 genlmsg_end(skb, hdr: nlh);
2254 mptcp_nl_mcast_send(net, nlskb: skb, gfp);
2255 return;
2256
2257nla_put_failure:
2258 nlmsg_free(skb);
2259}
2260
2261static struct genl_family mptcp_genl_family __ro_after_init = {
2262 .name = MPTCP_PM_NAME,
2263 .version = MPTCP_PM_VER,
2264 .netnsok = true,
2265 .module = THIS_MODULE,
2266 .ops = mptcp_pm_nl_ops,
2267 .n_ops = ARRAY_SIZE(mptcp_pm_nl_ops),
2268 .resv_start_op = MPTCP_PM_CMD_SUBFLOW_DESTROY + 1,
2269 .mcgrps = mptcp_pm_mcgrps,
2270 .n_mcgrps = ARRAY_SIZE(mptcp_pm_mcgrps),
2271};
2272
2273static int __net_init pm_nl_init_net(struct net *net)
2274{
2275 struct pm_nl_pernet *pernet = pm_nl_get_pernet(net);
2276
2277 INIT_LIST_HEAD_RCU(list: &pernet->local_addr_list);
2278
2279 /* Cit. 2 subflows ought to be enough for anybody. */
2280 pernet->subflows_max = 2;
2281 pernet->next_id = 1;
2282 pernet->stale_loss_cnt = 4;
2283 spin_lock_init(&pernet->lock);
2284
2285 /* No need to initialize other pernet fields, the struct is zeroed at
2286 * allocation time.
2287 */
2288
2289 return 0;
2290}
2291
2292static void __net_exit pm_nl_exit_net(struct list_head *net_list)
2293{
2294 struct net *net;
2295
2296 list_for_each_entry(net, net_list, exit_list) {
2297 struct pm_nl_pernet *pernet = pm_nl_get_pernet(net);
2298
2299 /* net is removed from namespace list, can't race with
2300 * other modifiers, also netns core already waited for a
2301 * RCU grace period.
2302 */
2303 __flush_addrs(list: &pernet->local_addr_list);
2304 }
2305}
2306
2307static struct pernet_operations mptcp_pm_pernet_ops = {
2308 .init = pm_nl_init_net,
2309 .exit_batch = pm_nl_exit_net,
2310 .id = &pm_nl_pernet_id,
2311 .size = sizeof(struct pm_nl_pernet),
2312};
2313
2314void __init mptcp_pm_nl_init(void)
2315{
2316 if (register_pernet_subsys(&mptcp_pm_pernet_ops) < 0)
2317 panic(fmt: "Failed to register MPTCP PM pernet subsystem.\n");
2318
2319 if (genl_register_family(family: &mptcp_genl_family))
2320 panic(fmt: "Failed to register MPTCP PM netlink family\n");
2321}
2322

source code of linux/net/mptcp/pm_netlink.c