1 // SPDX-License-Identifier: GPL-2.0
2 /* Multipath TCP
3 *
4 * Copyright (c) 2020, Red Hat, Inc.
5 */
6
7 #define pr_fmt(fmt) "MPTCP: " fmt
8
9 #include <linux/inet.h>
10 #include <linux/kernel.h>
11 #include <net/tcp.h>
12 #include <net/netns/generic.h>
13 #include <net/mptcp.h>
14 #include <net/genetlink.h>
15 #include <uapi/linux/mptcp.h>
16
17 #include "protocol.h"
18 #include "mib.h"
19
20 /* forward declaration */
21 static struct genl_family mptcp_genl_family;
22
23 static int pm_nl_pernet_id;
24
25 struct mptcp_pm_add_entry {
26 struct list_head list;
27 struct mptcp_addr_info addr;
28 struct timer_list add_timer;
29 struct mptcp_sock *sock;
30 u8 retrans_times;
31 };
32
33 struct pm_nl_pernet {
34 /* protects pernet updates */
35 spinlock_t lock;
36 struct list_head local_addr_list;
37 unsigned int addrs;
38 unsigned int stale_loss_cnt;
39 unsigned int add_addr_signal_max;
40 unsigned int add_addr_accept_max;
41 unsigned int local_addr_max;
42 unsigned int subflows_max;
43 unsigned int next_id;
44 DECLARE_BITMAP(id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1);
45 };
46
47 #define MPTCP_PM_ADDR_MAX 8
48 #define ADD_ADDR_RETRANS_MAX 3
49
pm_nl_get_pernet(const struct net * net)50 static struct pm_nl_pernet *pm_nl_get_pernet(const struct net *net)
51 {
52 return net_generic(net, pm_nl_pernet_id);
53 }
54
55 static struct pm_nl_pernet *
pm_nl_get_pernet_from_msk(const struct mptcp_sock * msk)56 pm_nl_get_pernet_from_msk(const struct mptcp_sock *msk)
57 {
58 return pm_nl_get_pernet(sock_net((struct sock *)msk));
59 }
60
mptcp_addresses_equal(const struct mptcp_addr_info * a,const struct mptcp_addr_info * b,bool use_port)61 bool mptcp_addresses_equal(const struct mptcp_addr_info *a,
62 const struct mptcp_addr_info *b, bool use_port)
63 {
64 bool addr_equals = false;
65
66 if (a->family == b->family) {
67 if (a->family == AF_INET)
68 addr_equals = a->addr.s_addr == b->addr.s_addr;
69 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
70 else
71 addr_equals = !ipv6_addr_cmp(&a->addr6, &b->addr6);
72 } else if (a->family == AF_INET) {
73 if (ipv6_addr_v4mapped(&b->addr6))
74 addr_equals = a->addr.s_addr == b->addr6.s6_addr32[3];
75 } else if (b->family == AF_INET) {
76 if (ipv6_addr_v4mapped(&a->addr6))
77 addr_equals = a->addr6.s6_addr32[3] == b->addr.s_addr;
78 #endif
79 }
80
81 if (!addr_equals)
82 return false;
83 if (!use_port)
84 return true;
85
86 return a->port == b->port;
87 }
88
local_address(const struct sock_common * skc,struct mptcp_addr_info * addr)89 static void local_address(const struct sock_common *skc,
90 struct mptcp_addr_info *addr)
91 {
92 addr->family = skc->skc_family;
93 addr->port = htons(skc->skc_num);
94 if (addr->family == AF_INET)
95 addr->addr.s_addr = skc->skc_rcv_saddr;
96 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
97 else if (addr->family == AF_INET6)
98 addr->addr6 = skc->skc_v6_rcv_saddr;
99 #endif
100 }
101
remote_address(const struct sock_common * skc,struct mptcp_addr_info * addr)102 static void remote_address(const struct sock_common *skc,
103 struct mptcp_addr_info *addr)
104 {
105 addr->family = skc->skc_family;
106 addr->port = skc->skc_dport;
107 if (addr->family == AF_INET)
108 addr->addr.s_addr = skc->skc_daddr;
109 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
110 else if (addr->family == AF_INET6)
111 addr->addr6 = skc->skc_v6_daddr;
112 #endif
113 }
114
lookup_subflow_by_saddr(const struct list_head * list,const struct mptcp_addr_info * saddr)115 static bool lookup_subflow_by_saddr(const struct list_head *list,
116 const struct mptcp_addr_info *saddr)
117 {
118 struct mptcp_subflow_context *subflow;
119 struct mptcp_addr_info cur;
120 struct sock_common *skc;
121
122 list_for_each_entry(subflow, list, node) {
123 skc = (struct sock_common *)mptcp_subflow_tcp_sock(subflow);
124
125 local_address(skc, &cur);
126 if (mptcp_addresses_equal(&cur, saddr, saddr->port))
127 return true;
128 }
129
130 return false;
131 }
132
lookup_subflow_by_daddr(const struct list_head * list,const struct mptcp_addr_info * daddr)133 static bool lookup_subflow_by_daddr(const struct list_head *list,
134 const struct mptcp_addr_info *daddr)
135 {
136 struct mptcp_subflow_context *subflow;
137 struct mptcp_addr_info cur;
138 struct sock_common *skc;
139
140 list_for_each_entry(subflow, list, node) {
141 skc = (struct sock_common *)mptcp_subflow_tcp_sock(subflow);
142
143 remote_address(skc, &cur);
144 if (mptcp_addresses_equal(&cur, daddr, daddr->port))
145 return true;
146 }
147
148 return false;
149 }
150
151 static struct mptcp_pm_addr_entry *
select_local_address(const struct pm_nl_pernet * pernet,const struct mptcp_sock * msk)152 select_local_address(const struct pm_nl_pernet *pernet,
153 const struct mptcp_sock *msk)
154 {
155 const struct sock *sk = (const struct sock *)msk;
156 struct mptcp_pm_addr_entry *entry, *ret = NULL;
157
158 msk_owned_by_me(msk);
159
160 rcu_read_lock();
161 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) {
162 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW))
163 continue;
164
165 if (!test_bit(entry->addr.id, msk->pm.id_avail_bitmap))
166 continue;
167
168 if (entry->addr.family != sk->sk_family) {
169 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
170 if ((entry->addr.family == AF_INET &&
171 !ipv6_addr_v4mapped(&sk->sk_v6_daddr)) ||
172 (sk->sk_family == AF_INET &&
173 !ipv6_addr_v4mapped(&entry->addr.addr6)))
174 #endif
175 continue;
176 }
177
178 ret = entry;
179 break;
180 }
181 rcu_read_unlock();
182 return ret;
183 }
184
185 static struct mptcp_pm_addr_entry *
select_signal_address(struct pm_nl_pernet * pernet,const struct mptcp_sock * msk)186 select_signal_address(struct pm_nl_pernet *pernet, const struct mptcp_sock *msk)
187 {
188 struct mptcp_pm_addr_entry *entry, *ret = NULL;
189
190 rcu_read_lock();
191 /* do not keep any additional per socket state, just signal
192 * the address list in order.
193 * Note: removal from the local address list during the msk life-cycle
194 * can lead to additional addresses not being announced.
195 */
196 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) {
197 if (!test_bit(entry->addr.id, msk->pm.id_avail_bitmap))
198 continue;
199
200 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL))
201 continue;
202
203 ret = entry;
204 break;
205 }
206 rcu_read_unlock();
207 return ret;
208 }
209
mptcp_pm_get_add_addr_signal_max(const struct mptcp_sock * msk)210 unsigned int mptcp_pm_get_add_addr_signal_max(const struct mptcp_sock *msk)
211 {
212 const struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk);
213
214 return READ_ONCE(pernet->add_addr_signal_max);
215 }
216 EXPORT_SYMBOL_GPL(mptcp_pm_get_add_addr_signal_max);
217
mptcp_pm_get_add_addr_accept_max(const struct mptcp_sock * msk)218 unsigned int mptcp_pm_get_add_addr_accept_max(const struct mptcp_sock *msk)
219 {
220 struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk);
221
222 return READ_ONCE(pernet->add_addr_accept_max);
223 }
224 EXPORT_SYMBOL_GPL(mptcp_pm_get_add_addr_accept_max);
225
mptcp_pm_get_subflows_max(const struct mptcp_sock * msk)226 unsigned int mptcp_pm_get_subflows_max(const struct mptcp_sock *msk)
227 {
228 struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk);
229
230 return READ_ONCE(pernet->subflows_max);
231 }
232 EXPORT_SYMBOL_GPL(mptcp_pm_get_subflows_max);
233
mptcp_pm_get_local_addr_max(const struct mptcp_sock * msk)234 unsigned int mptcp_pm_get_local_addr_max(const struct mptcp_sock *msk)
235 {
236 struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk);
237
238 return READ_ONCE(pernet->local_addr_max);
239 }
240 EXPORT_SYMBOL_GPL(mptcp_pm_get_local_addr_max);
241
mptcp_pm_nl_check_work_pending(struct mptcp_sock * msk)242 bool mptcp_pm_nl_check_work_pending(struct mptcp_sock *msk)
243 {
244 struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk);
245
246 if (msk->pm.subflows == mptcp_pm_get_subflows_max(msk) ||
247 (find_next_and_bit(pernet->id_bitmap, msk->pm.id_avail_bitmap,
248 MPTCP_PM_MAX_ADDR_ID + 1, 0) == MPTCP_PM_MAX_ADDR_ID + 1)) {
249 WRITE_ONCE(msk->pm.work_pending, false);
250 return false;
251 }
252 return true;
253 }
254
255 struct mptcp_pm_add_entry *
mptcp_lookup_anno_list_by_saddr(const struct mptcp_sock * msk,const struct mptcp_addr_info * addr)256 mptcp_lookup_anno_list_by_saddr(const struct mptcp_sock *msk,
257 const struct mptcp_addr_info *addr)
258 {
259 struct mptcp_pm_add_entry *entry;
260
261 lockdep_assert_held(&msk->pm.lock);
262
263 list_for_each_entry(entry, &msk->pm.anno_list, list) {
264 if (mptcp_addresses_equal(&entry->addr, addr, true))
265 return entry;
266 }
267
268 return NULL;
269 }
270
mptcp_pm_sport_in_anno_list(struct mptcp_sock * msk,const struct sock * sk)271 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk)
272 {
273 struct mptcp_pm_add_entry *entry;
274 struct mptcp_addr_info saddr;
275 bool ret = false;
276
277 local_address((struct sock_common *)sk, &saddr);
278
279 spin_lock_bh(&msk->pm.lock);
280 list_for_each_entry(entry, &msk->pm.anno_list, list) {
281 if (mptcp_addresses_equal(&entry->addr, &saddr, true)) {
282 ret = true;
283 goto out;
284 }
285 }
286
287 out:
288 spin_unlock_bh(&msk->pm.lock);
289 return ret;
290 }
291
mptcp_pm_add_timer(struct timer_list * timer)292 static void mptcp_pm_add_timer(struct timer_list *timer)
293 {
294 struct mptcp_pm_add_entry *entry = from_timer(entry, timer, add_timer);
295 struct mptcp_sock *msk = entry->sock;
296 struct sock *sk = (struct sock *)msk;
297
298 pr_debug("msk=%p", msk);
299
300 if (!msk)
301 return;
302
303 if (inet_sk_state_load(sk) == TCP_CLOSE)
304 return;
305
306 if (!entry->addr.id)
307 return;
308
309 if (mptcp_pm_should_add_signal_addr(msk)) {
310 sk_reset_timer(sk, timer, jiffies + TCP_RTO_MAX / 8);
311 goto out;
312 }
313
314 spin_lock_bh(&msk->pm.lock);
315
316 if (!mptcp_pm_should_add_signal_addr(msk)) {
317 pr_debug("retransmit ADD_ADDR id=%d", entry->addr.id);
318 mptcp_pm_announce_addr(msk, &entry->addr, false);
319 mptcp_pm_add_addr_send_ack(msk);
320 entry->retrans_times++;
321 }
322
323 if (entry->retrans_times < ADD_ADDR_RETRANS_MAX)
324 sk_reset_timer(sk, timer,
325 jiffies + mptcp_get_add_addr_timeout(sock_net(sk)));
326
327 spin_unlock_bh(&msk->pm.lock);
328
329 if (entry->retrans_times == ADD_ADDR_RETRANS_MAX)
330 mptcp_pm_subflow_established(msk);
331
332 out:
333 __sock_put(sk);
334 }
335
336 struct mptcp_pm_add_entry *
mptcp_pm_del_add_timer(struct mptcp_sock * msk,const struct mptcp_addr_info * addr,bool check_id)337 mptcp_pm_del_add_timer(struct mptcp_sock *msk,
338 const struct mptcp_addr_info *addr, bool check_id)
339 {
340 struct mptcp_pm_add_entry *entry;
341 struct sock *sk = (struct sock *)msk;
342
343 spin_lock_bh(&msk->pm.lock);
344 entry = mptcp_lookup_anno_list_by_saddr(msk, addr);
345 if (entry && (!check_id || entry->addr.id == addr->id))
346 entry->retrans_times = ADD_ADDR_RETRANS_MAX;
347 spin_unlock_bh(&msk->pm.lock);
348
349 if (entry && (!check_id || entry->addr.id == addr->id))
350 sk_stop_timer_sync(sk, &entry->add_timer);
351
352 return entry;
353 }
354
mptcp_pm_alloc_anno_list(struct mptcp_sock * msk,const struct mptcp_pm_addr_entry * entry)355 bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk,
356 const struct mptcp_pm_addr_entry *entry)
357 {
358 struct mptcp_pm_add_entry *add_entry = NULL;
359 struct sock *sk = (struct sock *)msk;
360 struct net *net = sock_net(sk);
361
362 lockdep_assert_held(&msk->pm.lock);
363
364 add_entry = mptcp_lookup_anno_list_by_saddr(msk, &entry->addr);
365
366 if (add_entry) {
367 if (mptcp_pm_is_kernel(msk))
368 return false;
369
370 sk_reset_timer(sk, &add_entry->add_timer,
371 jiffies + mptcp_get_add_addr_timeout(net));
372 return true;
373 }
374
375 add_entry = kmalloc(sizeof(*add_entry), GFP_ATOMIC);
376 if (!add_entry)
377 return false;
378
379 list_add(&add_entry->list, &msk->pm.anno_list);
380
381 add_entry->addr = entry->addr;
382 add_entry->sock = msk;
383 add_entry->retrans_times = 0;
384
385 timer_setup(&add_entry->add_timer, mptcp_pm_add_timer, 0);
386 sk_reset_timer(sk, &add_entry->add_timer,
387 jiffies + mptcp_get_add_addr_timeout(net));
388
389 return true;
390 }
391
mptcp_pm_free_anno_list(struct mptcp_sock * msk)392 void mptcp_pm_free_anno_list(struct mptcp_sock *msk)
393 {
394 struct mptcp_pm_add_entry *entry, *tmp;
395 struct sock *sk = (struct sock *)msk;
396 LIST_HEAD(free_list);
397
398 pr_debug("msk=%p", msk);
399
400 spin_lock_bh(&msk->pm.lock);
401 list_splice_init(&msk->pm.anno_list, &free_list);
402 spin_unlock_bh(&msk->pm.lock);
403
404 list_for_each_entry_safe(entry, tmp, &free_list, list) {
405 sk_stop_timer_sync(sk, &entry->add_timer);
406 kfree(entry);
407 }
408 }
409
lookup_address_in_vec(const struct mptcp_addr_info * addrs,unsigned int nr,const struct mptcp_addr_info * addr)410 static bool lookup_address_in_vec(const struct mptcp_addr_info *addrs, unsigned int nr,
411 const struct mptcp_addr_info *addr)
412 {
413 int i;
414
415 for (i = 0; i < nr; i++) {
416 if (addrs[i].id == addr->id)
417 return true;
418 }
419
420 return false;
421 }
422
423 /* Fill all the remote addresses into the array addrs[],
424 * and return the array size.
425 */
fill_remote_addresses_vec(struct mptcp_sock * msk,bool fullmesh,struct mptcp_addr_info * addrs)426 static unsigned int fill_remote_addresses_vec(struct mptcp_sock *msk, bool fullmesh,
427 struct mptcp_addr_info *addrs)
428 {
429 bool deny_id0 = READ_ONCE(msk->pm.remote_deny_join_id0);
430 struct sock *sk = (struct sock *)msk, *ssk;
431 struct mptcp_subflow_context *subflow;
432 struct mptcp_addr_info remote = { 0 };
433 unsigned int subflows_max;
434 int i = 0;
435
436 subflows_max = mptcp_pm_get_subflows_max(msk);
437 remote_address((struct sock_common *)sk, &remote);
438
439 /* Non-fullmesh endpoint, fill in the single entry
440 * corresponding to the primary MPC subflow remote address
441 */
442 if (!fullmesh) {
443 if (deny_id0)
444 return 0;
445
446 msk->pm.subflows++;
447 addrs[i++] = remote;
448 } else {
449 mptcp_for_each_subflow(msk, subflow) {
450 ssk = mptcp_subflow_tcp_sock(subflow);
451 remote_address((struct sock_common *)ssk, &addrs[i]);
452 addrs[i].id = subflow->remote_id;
453 if (deny_id0 && !addrs[i].id)
454 continue;
455
456 if (!lookup_address_in_vec(addrs, i, &addrs[i]) &&
457 msk->pm.subflows < subflows_max) {
458 msk->pm.subflows++;
459 i++;
460 }
461 }
462 }
463
464 return i;
465 }
466
__mptcp_pm_send_ack(struct mptcp_sock * msk,struct mptcp_subflow_context * subflow,bool prio,bool backup)467 static void __mptcp_pm_send_ack(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow,
468 bool prio, bool backup)
469 {
470 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
471 bool slow;
472
473 pr_debug("send ack for %s",
474 prio ? "mp_prio" : (mptcp_pm_should_add_signal(msk) ? "add_addr" : "rm_addr"));
475
476 slow = lock_sock_fast(ssk);
477 if (prio) {
478 if (subflow->backup != backup)
479 msk->last_snd = NULL;
480
481 subflow->send_mp_prio = 1;
482 subflow->backup = backup;
483 subflow->request_bkup = backup;
484 }
485
486 __mptcp_subflow_send_ack(ssk);
487 unlock_sock_fast(ssk, slow);
488 }
489
mptcp_pm_send_ack(struct mptcp_sock * msk,struct mptcp_subflow_context * subflow,bool prio,bool backup)490 static void mptcp_pm_send_ack(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow,
491 bool prio, bool backup)
492 {
493 spin_unlock_bh(&msk->pm.lock);
494 __mptcp_pm_send_ack(msk, subflow, prio, backup);
495 spin_lock_bh(&msk->pm.lock);
496 }
497
498 static struct mptcp_pm_addr_entry *
__lookup_addr_by_id(struct pm_nl_pernet * pernet,unsigned int id)499 __lookup_addr_by_id(struct pm_nl_pernet *pernet, unsigned int id)
500 {
501 struct mptcp_pm_addr_entry *entry;
502
503 list_for_each_entry(entry, &pernet->local_addr_list, list) {
504 if (entry->addr.id == id)
505 return entry;
506 }
507 return NULL;
508 }
509
510 static struct mptcp_pm_addr_entry *
__lookup_addr(struct pm_nl_pernet * pernet,const struct mptcp_addr_info * info,bool lookup_by_id)511 __lookup_addr(struct pm_nl_pernet *pernet, const struct mptcp_addr_info *info,
512 bool lookup_by_id)
513 {
514 struct mptcp_pm_addr_entry *entry;
515
516 list_for_each_entry(entry, &pernet->local_addr_list, list) {
517 if ((!lookup_by_id &&
518 mptcp_addresses_equal(&entry->addr, info, entry->addr.port)) ||
519 (lookup_by_id && entry->addr.id == info->id))
520 return entry;
521 }
522 return NULL;
523 }
524
mptcp_pm_create_subflow_or_signal_addr(struct mptcp_sock * msk)525 static void mptcp_pm_create_subflow_or_signal_addr(struct mptcp_sock *msk)
526 {
527 struct sock *sk = (struct sock *)msk;
528 struct mptcp_pm_addr_entry *local;
529 unsigned int add_addr_signal_max;
530 unsigned int local_addr_max;
531 struct pm_nl_pernet *pernet;
532 unsigned int subflows_max;
533
534 pernet = pm_nl_get_pernet(sock_net(sk));
535
536 add_addr_signal_max = mptcp_pm_get_add_addr_signal_max(msk);
537 local_addr_max = mptcp_pm_get_local_addr_max(msk);
538 subflows_max = mptcp_pm_get_subflows_max(msk);
539
540 /* do lazy endpoint usage accounting for the MPC subflows */
541 if (unlikely(!(msk->pm.status & BIT(MPTCP_PM_MPC_ENDPOINT_ACCOUNTED))) && msk->first) {
542 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(msk->first);
543 struct mptcp_pm_addr_entry *entry;
544 struct mptcp_addr_info mpc_addr;
545 bool backup = false;
546
547 local_address((struct sock_common *)msk->first, &mpc_addr);
548 rcu_read_lock();
549 entry = __lookup_addr(pernet, &mpc_addr, false);
550 if (entry) {
551 __clear_bit(entry->addr.id, msk->pm.id_avail_bitmap);
552 msk->mpc_endpoint_id = entry->addr.id;
553 backup = !!(entry->flags & MPTCP_PM_ADDR_FLAG_BACKUP);
554 }
555 rcu_read_unlock();
556
557 if (backup)
558 mptcp_pm_send_ack(msk, subflow, true, backup);
559
560 msk->pm.status |= BIT(MPTCP_PM_MPC_ENDPOINT_ACCOUNTED);
561 }
562
563 pr_debug("local %d:%d signal %d:%d subflows %d:%d\n",
564 msk->pm.local_addr_used, local_addr_max,
565 msk->pm.add_addr_signaled, add_addr_signal_max,
566 msk->pm.subflows, subflows_max);
567
568 /* check first for announce */
569 if (msk->pm.add_addr_signaled < add_addr_signal_max) {
570 local = select_signal_address(pernet, msk);
571
572 /* due to racing events on both ends we can reach here while
573 * previous add address is still running: if we invoke now
574 * mptcp_pm_announce_addr(), that will fail and the
575 * corresponding id will be marked as used.
576 * Instead let the PM machinery reschedule us when the
577 * current address announce will be completed.
578 */
579 if (msk->pm.addr_signal & BIT(MPTCP_ADD_ADDR_SIGNAL))
580 return;
581
582 if (local) {
583 if (mptcp_pm_alloc_anno_list(msk, local)) {
584 __clear_bit(local->addr.id, msk->pm.id_avail_bitmap);
585 msk->pm.add_addr_signaled++;
586 mptcp_pm_announce_addr(msk, &local->addr, false);
587 mptcp_pm_nl_addr_send_ack(msk);
588 }
589 }
590 }
591
592 /* check if should create a new subflow */
593 while (msk->pm.local_addr_used < local_addr_max &&
594 msk->pm.subflows < subflows_max) {
595 struct mptcp_addr_info addrs[MPTCP_PM_ADDR_MAX];
596 bool fullmesh;
597 int i, nr;
598
599 local = select_local_address(pernet, msk);
600 if (!local)
601 break;
602
603 fullmesh = !!(local->flags & MPTCP_PM_ADDR_FLAG_FULLMESH);
604
605 msk->pm.local_addr_used++;
606 nr = fill_remote_addresses_vec(msk, fullmesh, addrs);
607 if (nr)
608 __clear_bit(local->addr.id, msk->pm.id_avail_bitmap);
609 spin_unlock_bh(&msk->pm.lock);
610 for (i = 0; i < nr; i++)
611 __mptcp_subflow_connect(sk, &local->addr, &addrs[i]);
612 spin_lock_bh(&msk->pm.lock);
613 }
614 mptcp_pm_nl_check_work_pending(msk);
615 }
616
mptcp_pm_nl_fully_established(struct mptcp_sock * msk)617 static void mptcp_pm_nl_fully_established(struct mptcp_sock *msk)
618 {
619 mptcp_pm_create_subflow_or_signal_addr(msk);
620 }
621
mptcp_pm_nl_subflow_established(struct mptcp_sock * msk)622 static void mptcp_pm_nl_subflow_established(struct mptcp_sock *msk)
623 {
624 mptcp_pm_create_subflow_or_signal_addr(msk);
625 }
626
627 /* Fill all the local addresses into the array addrs[],
628 * and return the array size.
629 */
fill_local_addresses_vec(struct mptcp_sock * msk,struct mptcp_addr_info * addrs)630 static unsigned int fill_local_addresses_vec(struct mptcp_sock *msk,
631 struct mptcp_addr_info *addrs)
632 {
633 struct sock *sk = (struct sock *)msk;
634 struct mptcp_pm_addr_entry *entry;
635 struct mptcp_addr_info local;
636 struct pm_nl_pernet *pernet;
637 unsigned int subflows_max;
638 int i = 0;
639
640 pernet = pm_nl_get_pernet_from_msk(msk);
641 subflows_max = mptcp_pm_get_subflows_max(msk);
642
643 rcu_read_lock();
644 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) {
645 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_FULLMESH))
646 continue;
647
648 if (entry->addr.family != sk->sk_family) {
649 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
650 if ((entry->addr.family == AF_INET &&
651 !ipv6_addr_v4mapped(&sk->sk_v6_daddr)) ||
652 (sk->sk_family == AF_INET &&
653 !ipv6_addr_v4mapped(&entry->addr.addr6)))
654 #endif
655 continue;
656 }
657
658 if (msk->pm.subflows < subflows_max) {
659 msk->pm.subflows++;
660 addrs[i++] = entry->addr;
661 }
662 }
663 rcu_read_unlock();
664
665 /* If the array is empty, fill in the single
666 * 'IPADDRANY' local address
667 */
668 if (!i) {
669 memset(&local, 0, sizeof(local));
670 local.family = msk->pm.remote.family;
671
672 msk->pm.subflows++;
673 addrs[i++] = local;
674 }
675
676 return i;
677 }
678
mptcp_pm_nl_add_addr_received(struct mptcp_sock * msk)679 static void mptcp_pm_nl_add_addr_received(struct mptcp_sock *msk)
680 {
681 struct mptcp_addr_info addrs[MPTCP_PM_ADDR_MAX];
682 struct sock *sk = (struct sock *)msk;
683 unsigned int add_addr_accept_max;
684 struct mptcp_addr_info remote;
685 unsigned int subflows_max;
686 int i, nr;
687
688 add_addr_accept_max = mptcp_pm_get_add_addr_accept_max(msk);
689 subflows_max = mptcp_pm_get_subflows_max(msk);
690
691 pr_debug("accepted %d:%d remote family %d",
692 msk->pm.add_addr_accepted, add_addr_accept_max,
693 msk->pm.remote.family);
694
695 remote = msk->pm.remote;
696 mptcp_pm_announce_addr(msk, &remote, true);
697 mptcp_pm_nl_addr_send_ack(msk);
698
699 if (lookup_subflow_by_daddr(&msk->conn_list, &remote))
700 return;
701
702 /* pick id 0 port, if none is provided the remote address */
703 if (!remote.port)
704 remote.port = sk->sk_dport;
705
706 /* connect to the specified remote address, using whatever
707 * local address the routing configuration will pick.
708 */
709 nr = fill_local_addresses_vec(msk, addrs);
710
711 msk->pm.add_addr_accepted++;
712 if (msk->pm.add_addr_accepted >= add_addr_accept_max ||
713 msk->pm.subflows >= subflows_max)
714 WRITE_ONCE(msk->pm.accept_addr, false);
715
716 spin_unlock_bh(&msk->pm.lock);
717 for (i = 0; i < nr; i++)
718 __mptcp_subflow_connect(sk, &addrs[i], &remote);
719 spin_lock_bh(&msk->pm.lock);
720 }
721
mptcp_pm_nl_addr_send_ack(struct mptcp_sock * msk)722 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk)
723 {
724 struct mptcp_subflow_context *subflow;
725
726 msk_owned_by_me(msk);
727 lockdep_assert_held(&msk->pm.lock);
728
729 if (!mptcp_pm_should_add_signal(msk) &&
730 !mptcp_pm_should_rm_signal(msk))
731 return;
732
733 subflow = list_first_entry_or_null(&msk->conn_list, typeof(*subflow), node);
734 if (subflow)
735 mptcp_pm_send_ack(msk, subflow, false, false);
736 }
737
mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock * msk,struct mptcp_addr_info * addr,struct mptcp_addr_info * rem,u8 bkup)738 int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk,
739 struct mptcp_addr_info *addr,
740 struct mptcp_addr_info *rem,
741 u8 bkup)
742 {
743 struct mptcp_subflow_context *subflow;
744
745 pr_debug("bkup=%d", bkup);
746
747 mptcp_for_each_subflow(msk, subflow) {
748 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
749 struct mptcp_addr_info local, remote;
750
751 local_address((struct sock_common *)ssk, &local);
752 if (!mptcp_addresses_equal(&local, addr, addr->port))
753 continue;
754
755 if (rem && rem->family != AF_UNSPEC) {
756 remote_address((struct sock_common *)ssk, &remote);
757 if (!mptcp_addresses_equal(&remote, rem, rem->port))
758 continue;
759 }
760
761 __mptcp_pm_send_ack(msk, subflow, true, bkup);
762 return 0;
763 }
764
765 return -EINVAL;
766 }
767
mptcp_local_id_match(const struct mptcp_sock * msk,u8 local_id,u8 id)768 static bool mptcp_local_id_match(const struct mptcp_sock *msk, u8 local_id, u8 id)
769 {
770 return local_id == id || (!local_id && msk->mpc_endpoint_id == id);
771 }
772
mptcp_pm_nl_rm_addr_or_subflow(struct mptcp_sock * msk,const struct mptcp_rm_list * rm_list,enum linux_mptcp_mib_field rm_type)773 static void mptcp_pm_nl_rm_addr_or_subflow(struct mptcp_sock *msk,
774 const struct mptcp_rm_list *rm_list,
775 enum linux_mptcp_mib_field rm_type)
776 {
777 struct mptcp_subflow_context *subflow, *tmp;
778 struct sock *sk = (struct sock *)msk;
779 u8 i;
780
781 pr_debug("%s rm_list_nr %d",
782 rm_type == MPTCP_MIB_RMADDR ? "address" : "subflow", rm_list->nr);
783
784 msk_owned_by_me(msk);
785
786 if (sk->sk_state == TCP_LISTEN)
787 return;
788
789 if (!rm_list->nr)
790 return;
791
792 if (list_empty(&msk->conn_list))
793 return;
794
795 for (i = 0; i < rm_list->nr; i++) {
796 u8 rm_id = rm_list->ids[i];
797 bool removed = false;
798
799 mptcp_for_each_subflow_safe(msk, subflow, tmp) {
800 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
801 int how = RCV_SHUTDOWN | SEND_SHUTDOWN;
802 u8 id = subflow->local_id;
803
804 if (rm_type == MPTCP_MIB_RMADDR && subflow->remote_id != rm_id)
805 continue;
806 if (rm_type == MPTCP_MIB_RMSUBFLOW && !mptcp_local_id_match(msk, id, rm_id))
807 continue;
808
809 pr_debug(" -> %s rm_list_ids[%d]=%u local_id=%u remote_id=%u mpc_id=%u",
810 rm_type == MPTCP_MIB_RMADDR ? "address" : "subflow",
811 i, rm_id, subflow->local_id, subflow->remote_id,
812 msk->mpc_endpoint_id);
813 spin_unlock_bh(&msk->pm.lock);
814 mptcp_subflow_shutdown(sk, ssk, how);
815
816 /* the following takes care of updating the subflows counter */
817 mptcp_close_ssk(sk, ssk, subflow);
818 spin_lock_bh(&msk->pm.lock);
819
820 removed = true;
821 __MPTCP_INC_STATS(sock_net(sk), rm_type);
822 }
823 if (rm_type == MPTCP_MIB_RMSUBFLOW)
824 __set_bit(rm_id ? rm_id : msk->mpc_endpoint_id, msk->pm.id_avail_bitmap);
825 if (!removed)
826 continue;
827
828 if (!mptcp_pm_is_kernel(msk))
829 continue;
830
831 if (rm_type == MPTCP_MIB_RMADDR) {
832 msk->pm.add_addr_accepted--;
833 WRITE_ONCE(msk->pm.accept_addr, true);
834 } else if (rm_type == MPTCP_MIB_RMSUBFLOW) {
835 msk->pm.local_addr_used--;
836 }
837 }
838 }
839
mptcp_pm_nl_rm_addr_received(struct mptcp_sock * msk)840 static void mptcp_pm_nl_rm_addr_received(struct mptcp_sock *msk)
841 {
842 mptcp_pm_nl_rm_addr_or_subflow(msk, &msk->pm.rm_list_rx, MPTCP_MIB_RMADDR);
843 }
844
mptcp_pm_nl_rm_subflow_received(struct mptcp_sock * msk,const struct mptcp_rm_list * rm_list)845 void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk,
846 const struct mptcp_rm_list *rm_list)
847 {
848 mptcp_pm_nl_rm_addr_or_subflow(msk, rm_list, MPTCP_MIB_RMSUBFLOW);
849 }
850
mptcp_pm_nl_work(struct mptcp_sock * msk)851 void mptcp_pm_nl_work(struct mptcp_sock *msk)
852 {
853 struct mptcp_pm_data *pm = &msk->pm;
854
855 msk_owned_by_me(msk);
856
857 if (!(pm->status & MPTCP_PM_WORK_MASK))
858 return;
859
860 spin_lock_bh(&msk->pm.lock);
861
862 pr_debug("msk=%p status=%x", msk, pm->status);
863 if (pm->status & BIT(MPTCP_PM_ADD_ADDR_RECEIVED)) {
864 pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_RECEIVED);
865 mptcp_pm_nl_add_addr_received(msk);
866 }
867 if (pm->status & BIT(MPTCP_PM_ADD_ADDR_SEND_ACK)) {
868 pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_SEND_ACK);
869 mptcp_pm_nl_addr_send_ack(msk);
870 }
871 if (pm->status & BIT(MPTCP_PM_RM_ADDR_RECEIVED)) {
872 pm->status &= ~BIT(MPTCP_PM_RM_ADDR_RECEIVED);
873 mptcp_pm_nl_rm_addr_received(msk);
874 }
875 if (pm->status & BIT(MPTCP_PM_ESTABLISHED)) {
876 pm->status &= ~BIT(MPTCP_PM_ESTABLISHED);
877 mptcp_pm_nl_fully_established(msk);
878 }
879 if (pm->status & BIT(MPTCP_PM_SUBFLOW_ESTABLISHED)) {
880 pm->status &= ~BIT(MPTCP_PM_SUBFLOW_ESTABLISHED);
881 mptcp_pm_nl_subflow_established(msk);
882 }
883
884 spin_unlock_bh(&msk->pm.lock);
885 }
886
address_use_port(struct mptcp_pm_addr_entry * entry)887 static bool address_use_port(struct mptcp_pm_addr_entry *entry)
888 {
889 return (entry->flags &
890 (MPTCP_PM_ADDR_FLAG_SIGNAL | MPTCP_PM_ADDR_FLAG_SUBFLOW)) ==
891 MPTCP_PM_ADDR_FLAG_SIGNAL;
892 }
893
894 /* caller must ensure the RCU grace period is already elapsed */
__mptcp_pm_release_addr_entry(struct mptcp_pm_addr_entry * entry)895 static void __mptcp_pm_release_addr_entry(struct mptcp_pm_addr_entry *entry)
896 {
897 if (entry->lsk)
898 sock_release(entry->lsk);
899 kfree(entry);
900 }
901
mptcp_pm_nl_append_new_local_addr(struct pm_nl_pernet * pernet,struct mptcp_pm_addr_entry * entry)902 static int mptcp_pm_nl_append_new_local_addr(struct pm_nl_pernet *pernet,
903 struct mptcp_pm_addr_entry *entry)
904 {
905 struct mptcp_pm_addr_entry *cur, *del_entry = NULL;
906 unsigned int addr_max;
907 int ret = -EINVAL;
908
909 spin_lock_bh(&pernet->lock);
910 /* to keep the code simple, don't do IDR-like allocation for address ID,
911 * just bail when we exceed limits
912 */
913 if (pernet->next_id == MPTCP_PM_MAX_ADDR_ID)
914 pernet->next_id = 1;
915 if (pernet->addrs >= MPTCP_PM_ADDR_MAX)
916 goto out;
917 if (test_bit(entry->addr.id, pernet->id_bitmap))
918 goto out;
919
920 /* do not insert duplicate address, differentiate on port only
921 * singled addresses
922 */
923 if (!address_use_port(entry))
924 entry->addr.port = 0;
925 list_for_each_entry(cur, &pernet->local_addr_list, list) {
926 if (mptcp_addresses_equal(&cur->addr, &entry->addr,
927 cur->addr.port || entry->addr.port)) {
928 /* allow replacing the exiting endpoint only if such
929 * endpoint is an implicit one and the user-space
930 * did not provide an endpoint id
931 */
932 if (!(cur->flags & MPTCP_PM_ADDR_FLAG_IMPLICIT))
933 goto out;
934 if (entry->addr.id)
935 goto out;
936
937 pernet->addrs--;
938 entry->addr.id = cur->addr.id;
939 list_del_rcu(&cur->list);
940 del_entry = cur;
941 break;
942 }
943 }
944
945 if (!entry->addr.id) {
946 find_next:
947 entry->addr.id = find_next_zero_bit(pernet->id_bitmap,
948 MPTCP_PM_MAX_ADDR_ID + 1,
949 pernet->next_id);
950 if (!entry->addr.id && pernet->next_id != 1) {
951 pernet->next_id = 1;
952 goto find_next;
953 }
954 }
955
956 if (!entry->addr.id)
957 goto out;
958
959 __set_bit(entry->addr.id, pernet->id_bitmap);
960 if (entry->addr.id > pernet->next_id)
961 pernet->next_id = entry->addr.id;
962
963 if (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL) {
964 addr_max = pernet->add_addr_signal_max;
965 WRITE_ONCE(pernet->add_addr_signal_max, addr_max + 1);
966 }
967 if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) {
968 addr_max = pernet->local_addr_max;
969 WRITE_ONCE(pernet->local_addr_max, addr_max + 1);
970 }
971
972 pernet->addrs++;
973 if (!entry->addr.port)
974 list_add_tail_rcu(&entry->list, &pernet->local_addr_list);
975 else
976 list_add_rcu(&entry->list, &pernet->local_addr_list);
977 ret = entry->addr.id;
978
979 out:
980 spin_unlock_bh(&pernet->lock);
981
982 /* just replaced an existing entry, free it */
983 if (del_entry) {
984 synchronize_rcu();
985 __mptcp_pm_release_addr_entry(del_entry);
986 }
987 return ret;
988 }
989
mptcp_pm_nl_create_listen_socket(struct sock * sk,struct mptcp_pm_addr_entry * entry)990 static int mptcp_pm_nl_create_listen_socket(struct sock *sk,
991 struct mptcp_pm_addr_entry *entry)
992 {
993 int addrlen = sizeof(struct sockaddr_in);
994 struct sockaddr_storage addr;
995 struct mptcp_sock *msk;
996 struct socket *ssock;
997 int backlog = 1024;
998 int err;
999
1000 err = sock_create_kern(sock_net(sk), entry->addr.family,
1001 SOCK_STREAM, IPPROTO_MPTCP, &entry->lsk);
1002 if (err)
1003 return err;
1004
1005 msk = mptcp_sk(entry->lsk->sk);
1006 if (!msk) {
1007 err = -EINVAL;
1008 goto out;
1009 }
1010
1011 ssock = __mptcp_nmpc_socket(msk);
1012 if (!ssock) {
1013 err = -EINVAL;
1014 goto out;
1015 }
1016
1017 mptcp_info2sockaddr(&entry->addr, &addr, entry->addr.family);
1018 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
1019 if (entry->addr.family == AF_INET6)
1020 addrlen = sizeof(struct sockaddr_in6);
1021 #endif
1022 err = kernel_bind(ssock, (struct sockaddr *)&addr, addrlen);
1023 if (err) {
1024 pr_warn("kernel_bind error, err=%d", err);
1025 goto out;
1026 }
1027
1028 err = kernel_listen(ssock, backlog);
1029 if (err) {
1030 pr_warn("kernel_listen error, err=%d", err);
1031 goto out;
1032 }
1033
1034 return 0;
1035
1036 out:
1037 sock_release(entry->lsk);
1038 return err;
1039 }
1040
mptcp_pm_nl_get_local_id(struct mptcp_sock * msk,struct sock_common * skc)1041 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct sock_common *skc)
1042 {
1043 struct mptcp_pm_addr_entry *entry;
1044 struct mptcp_addr_info skc_local;
1045 struct mptcp_addr_info msk_local;
1046 struct pm_nl_pernet *pernet;
1047 int ret = -1;
1048
1049 if (WARN_ON_ONCE(!msk))
1050 return -1;
1051
1052 /* The 0 ID mapping is defined by the first subflow, copied into the msk
1053 * addr
1054 */
1055 local_address((struct sock_common *)msk, &msk_local);
1056 local_address((struct sock_common *)skc, &skc_local);
1057 if (mptcp_addresses_equal(&msk_local, &skc_local, false))
1058 return 0;
1059
1060 if (mptcp_pm_is_userspace(msk))
1061 return mptcp_userspace_pm_get_local_id(msk, &skc_local);
1062
1063 pernet = pm_nl_get_pernet_from_msk(msk);
1064
1065 rcu_read_lock();
1066 list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) {
1067 if (mptcp_addresses_equal(&entry->addr, &skc_local, entry->addr.port)) {
1068 ret = entry->addr.id;
1069 break;
1070 }
1071 }
1072 rcu_read_unlock();
1073 if (ret >= 0)
1074 return ret;
1075
1076 /* address not found, add to local list */
1077 entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
1078 if (!entry)
1079 return -ENOMEM;
1080
1081 entry->addr = skc_local;
1082 entry->addr.id = 0;
1083 entry->addr.port = 0;
1084 entry->ifindex = 0;
1085 entry->flags = MPTCP_PM_ADDR_FLAG_IMPLICIT;
1086 entry->lsk = NULL;
1087 ret = mptcp_pm_nl_append_new_local_addr(pernet, entry);
1088 if (ret < 0)
1089 kfree(entry);
1090
1091 return ret;
1092 }
1093
1094 #define MPTCP_PM_CMD_GRP_OFFSET 0
1095 #define MPTCP_PM_EV_GRP_OFFSET 1
1096
1097 static const struct genl_multicast_group mptcp_pm_mcgrps[] = {
1098 [MPTCP_PM_CMD_GRP_OFFSET] = { .name = MPTCP_PM_CMD_GRP_NAME, },
1099 [MPTCP_PM_EV_GRP_OFFSET] = { .name = MPTCP_PM_EV_GRP_NAME,
1100 .flags = GENL_UNS_ADMIN_PERM,
1101 },
1102 };
1103
1104 static const struct nla_policy
1105 mptcp_pm_addr_policy[MPTCP_PM_ADDR_ATTR_MAX + 1] = {
1106 [MPTCP_PM_ADDR_ATTR_FAMILY] = { .type = NLA_U16, },
1107 [MPTCP_PM_ADDR_ATTR_ID] = { .type = NLA_U8, },
1108 [MPTCP_PM_ADDR_ATTR_ADDR4] = { .type = NLA_U32, },
1109 [MPTCP_PM_ADDR_ATTR_ADDR6] =
1110 NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)),
1111 [MPTCP_PM_ADDR_ATTR_PORT] = { .type = NLA_U16 },
1112 [MPTCP_PM_ADDR_ATTR_FLAGS] = { .type = NLA_U32 },
1113 [MPTCP_PM_ADDR_ATTR_IF_IDX] = { .type = NLA_S32 },
1114 };
1115
1116 static const struct nla_policy mptcp_pm_policy[MPTCP_PM_ATTR_MAX + 1] = {
1117 [MPTCP_PM_ATTR_ADDR] =
1118 NLA_POLICY_NESTED(mptcp_pm_addr_policy),
1119 [MPTCP_PM_ATTR_RCV_ADD_ADDRS] = { .type = NLA_U32, },
1120 [MPTCP_PM_ATTR_SUBFLOWS] = { .type = NLA_U32, },
1121 [MPTCP_PM_ATTR_TOKEN] = { .type = NLA_U32, },
1122 [MPTCP_PM_ATTR_LOC_ID] = { .type = NLA_U8, },
1123 [MPTCP_PM_ATTR_ADDR_REMOTE] =
1124 NLA_POLICY_NESTED(mptcp_pm_addr_policy),
1125 };
1126
mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock * msk,struct sock * ssk)1127 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk)
1128 {
1129 struct mptcp_subflow_context *iter, *subflow = mptcp_subflow_ctx(ssk);
1130 struct sock *sk = (struct sock *)msk;
1131 unsigned int active_max_loss_cnt;
1132 struct net *net = sock_net(sk);
1133 unsigned int stale_loss_cnt;
1134 bool slow;
1135
1136 stale_loss_cnt = mptcp_stale_loss_cnt(net);
1137 if (subflow->stale || !stale_loss_cnt || subflow->stale_count <= stale_loss_cnt)
1138 return;
1139
1140 /* look for another available subflow not in loss state */
1141 active_max_loss_cnt = max_t(int, stale_loss_cnt - 1, 1);
1142 mptcp_for_each_subflow(msk, iter) {
1143 if (iter != subflow && mptcp_subflow_active(iter) &&
1144 iter->stale_count < active_max_loss_cnt) {
1145 /* we have some alternatives, try to mark this subflow as idle ...*/
1146 slow = lock_sock_fast(ssk);
1147 if (!tcp_rtx_and_write_queues_empty(ssk)) {
1148 subflow->stale = 1;
1149 __mptcp_retransmit_pending_data(sk);
1150 MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_SUBFLOWSTALE);
1151 }
1152 unlock_sock_fast(ssk, slow);
1153
1154 /* always try to push the pending data regardless of re-injections:
1155 * we can possibly use backup subflows now, and subflow selection
1156 * is cheap under the msk socket lock
1157 */
1158 __mptcp_push_pending(sk, 0);
1159 return;
1160 }
1161 }
1162 }
1163
mptcp_pm_family_to_addr(int family)1164 static int mptcp_pm_family_to_addr(int family)
1165 {
1166 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
1167 if (family == AF_INET6)
1168 return MPTCP_PM_ADDR_ATTR_ADDR6;
1169 #endif
1170 return MPTCP_PM_ADDR_ATTR_ADDR4;
1171 }
1172
mptcp_pm_parse_pm_addr_attr(struct nlattr * tb[],const struct nlattr * attr,struct genl_info * info,struct mptcp_addr_info * addr,bool require_family)1173 static int mptcp_pm_parse_pm_addr_attr(struct nlattr *tb[],
1174 const struct nlattr *attr,
1175 struct genl_info *info,
1176 struct mptcp_addr_info *addr,
1177 bool require_family)
1178 {
1179 int err, addr_addr;
1180
1181 if (!attr) {
1182 GENL_SET_ERR_MSG(info, "missing address info");
1183 return -EINVAL;
1184 }
1185
1186 /* no validation needed - was already done via nested policy */
1187 err = nla_parse_nested_deprecated(tb, MPTCP_PM_ADDR_ATTR_MAX, attr,
1188 mptcp_pm_addr_policy, info->extack);
1189 if (err)
1190 return err;
1191
1192 if (tb[MPTCP_PM_ADDR_ATTR_ID])
1193 addr->id = nla_get_u8(tb[MPTCP_PM_ADDR_ATTR_ID]);
1194
1195 if (!tb[MPTCP_PM_ADDR_ATTR_FAMILY]) {
1196 if (!require_family)
1197 return err;
1198
1199 NL_SET_ERR_MSG_ATTR(info->extack, attr,
1200 "missing family");
1201 return -EINVAL;
1202 }
1203
1204 addr->family = nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_FAMILY]);
1205 if (addr->family != AF_INET
1206 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
1207 && addr->family != AF_INET6
1208 #endif
1209 ) {
1210 NL_SET_ERR_MSG_ATTR(info->extack, attr,
1211 "unknown address family");
1212 return -EINVAL;
1213 }
1214 addr_addr = mptcp_pm_family_to_addr(addr->family);
1215 if (!tb[addr_addr]) {
1216 NL_SET_ERR_MSG_ATTR(info->extack, attr,
1217 "missing address data");
1218 return -EINVAL;
1219 }
1220
1221 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
1222 if (addr->family == AF_INET6)
1223 addr->addr6 = nla_get_in6_addr(tb[addr_addr]);
1224 else
1225 #endif
1226 addr->addr.s_addr = nla_get_in_addr(tb[addr_addr]);
1227
1228 if (tb[MPTCP_PM_ADDR_ATTR_PORT])
1229 addr->port = htons(nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_PORT]));
1230
1231 return err;
1232 }
1233
mptcp_pm_parse_addr(struct nlattr * attr,struct genl_info * info,struct mptcp_addr_info * addr)1234 int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info,
1235 struct mptcp_addr_info *addr)
1236 {
1237 struct nlattr *tb[MPTCP_PM_ADDR_ATTR_MAX + 1];
1238
1239 memset(addr, 0, sizeof(*addr));
1240
1241 return mptcp_pm_parse_pm_addr_attr(tb, attr, info, addr, true);
1242 }
1243
mptcp_pm_parse_entry(struct nlattr * attr,struct genl_info * info,bool require_family,struct mptcp_pm_addr_entry * entry)1244 int mptcp_pm_parse_entry(struct nlattr *attr, struct genl_info *info,
1245 bool require_family,
1246 struct mptcp_pm_addr_entry *entry)
1247 {
1248 struct nlattr *tb[MPTCP_PM_ADDR_ATTR_MAX + 1];
1249 int err;
1250
1251 memset(entry, 0, sizeof(*entry));
1252
1253 err = mptcp_pm_parse_pm_addr_attr(tb, attr, info, &entry->addr, require_family);
1254 if (err)
1255 return err;
1256
1257 if (tb[MPTCP_PM_ADDR_ATTR_IF_IDX]) {
1258 u32 val = nla_get_s32(tb[MPTCP_PM_ADDR_ATTR_IF_IDX]);
1259
1260 entry->ifindex = val;
1261 }
1262
1263 if (tb[MPTCP_PM_ADDR_ATTR_FLAGS])
1264 entry->flags = nla_get_u32(tb[MPTCP_PM_ADDR_ATTR_FLAGS]);
1265
1266 if (tb[MPTCP_PM_ADDR_ATTR_PORT])
1267 entry->addr.port = htons(nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_PORT]));
1268
1269 return 0;
1270 }
1271
genl_info_pm_nl(struct genl_info * info)1272 static struct pm_nl_pernet *genl_info_pm_nl(struct genl_info *info)
1273 {
1274 return pm_nl_get_pernet(genl_info_net(info));
1275 }
1276
mptcp_nl_add_subflow_or_signal_addr(struct net * net)1277 static int mptcp_nl_add_subflow_or_signal_addr(struct net *net)
1278 {
1279 struct mptcp_sock *msk;
1280 long s_slot = 0, s_num = 0;
1281
1282 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) {
1283 struct sock *sk = (struct sock *)msk;
1284
1285 if (!READ_ONCE(msk->fully_established) ||
1286 mptcp_pm_is_userspace(msk))
1287 goto next;
1288
1289 lock_sock(sk);
1290 spin_lock_bh(&msk->pm.lock);
1291 mptcp_pm_create_subflow_or_signal_addr(msk);
1292 spin_unlock_bh(&msk->pm.lock);
1293 release_sock(sk);
1294
1295 next:
1296 sock_put(sk);
1297 cond_resched();
1298 }
1299
1300 return 0;
1301 }
1302
mptcp_nl_cmd_add_addr(struct sk_buff * skb,struct genl_info * info)1303 static int mptcp_nl_cmd_add_addr(struct sk_buff *skb, struct genl_info *info)
1304 {
1305 struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR];
1306 struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
1307 struct mptcp_pm_addr_entry addr, *entry;
1308 int ret;
1309
1310 ret = mptcp_pm_parse_entry(attr, info, true, &addr);
1311 if (ret < 0)
1312 return ret;
1313
1314 if (addr.addr.port && !(addr.flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) {
1315 GENL_SET_ERR_MSG(info, "flags must have signal when using port");
1316 return -EINVAL;
1317 }
1318
1319 if (addr.flags & MPTCP_PM_ADDR_FLAG_SIGNAL &&
1320 addr.flags & MPTCP_PM_ADDR_FLAG_FULLMESH) {
1321 GENL_SET_ERR_MSG(info, "flags mustn't have both signal and fullmesh");
1322 return -EINVAL;
1323 }
1324
1325 if (addr.flags & MPTCP_PM_ADDR_FLAG_IMPLICIT) {
1326 GENL_SET_ERR_MSG(info, "can't create IMPLICIT endpoint");
1327 return -EINVAL;
1328 }
1329
1330 entry = kmalloc(sizeof(*entry), GFP_KERNEL_ACCOUNT);
1331 if (!entry) {
1332 GENL_SET_ERR_MSG(info, "can't allocate addr");
1333 return -ENOMEM;
1334 }
1335
1336 *entry = addr;
1337 if (entry->addr.port) {
1338 ret = mptcp_pm_nl_create_listen_socket(skb->sk, entry);
1339 if (ret) {
1340 GENL_SET_ERR_MSG(info, "create listen socket error");
1341 kfree(entry);
1342 return ret;
1343 }
1344 }
1345 ret = mptcp_pm_nl_append_new_local_addr(pernet, entry);
1346 if (ret < 0) {
1347 GENL_SET_ERR_MSG(info, "too many addresses or duplicate one");
1348 if (entry->lsk)
1349 sock_release(entry->lsk);
1350 kfree(entry);
1351 return ret;
1352 }
1353
1354 mptcp_nl_add_subflow_or_signal_addr(sock_net(skb->sk));
1355
1356 return 0;
1357 }
1358
mptcp_pm_get_flags_and_ifindex_by_id(struct mptcp_sock * msk,unsigned int id,u8 * flags,int * ifindex)1359 int mptcp_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, unsigned int id,
1360 u8 *flags, int *ifindex)
1361 {
1362 struct mptcp_pm_addr_entry *entry;
1363 struct sock *sk = (struct sock *)msk;
1364 struct net *net = sock_net(sk);
1365
1366 *flags = 0;
1367 *ifindex = 0;
1368
1369 if (id) {
1370 if (mptcp_pm_is_userspace(msk))
1371 return mptcp_userspace_pm_get_flags_and_ifindex_by_id(msk,
1372 id,
1373 flags,
1374 ifindex);
1375
1376 rcu_read_lock();
1377 entry = __lookup_addr_by_id(pm_nl_get_pernet(net), id);
1378 if (entry) {
1379 *flags = entry->flags;
1380 *ifindex = entry->ifindex;
1381 }
1382 rcu_read_unlock();
1383 }
1384
1385 return 0;
1386 }
1387
remove_anno_list_by_saddr(struct mptcp_sock * msk,const struct mptcp_addr_info * addr)1388 static bool remove_anno_list_by_saddr(struct mptcp_sock *msk,
1389 const struct mptcp_addr_info *addr)
1390 {
1391 struct mptcp_pm_add_entry *entry;
1392
1393 entry = mptcp_pm_del_add_timer(msk, addr, false);
1394 if (entry) {
1395 list_del(&entry->list);
1396 kfree(entry);
1397 return true;
1398 }
1399
1400 return false;
1401 }
1402
mptcp_pm_remove_anno_addr(struct mptcp_sock * msk,const struct mptcp_addr_info * addr,bool force)1403 static bool mptcp_pm_remove_anno_addr(struct mptcp_sock *msk,
1404 const struct mptcp_addr_info *addr,
1405 bool force)
1406 {
1407 struct mptcp_rm_list list = { .nr = 0 };
1408 bool ret;
1409
1410 list.ids[list.nr++] = addr->id;
1411
1412 ret = remove_anno_list_by_saddr(msk, addr);
1413 if (ret || force) {
1414 spin_lock_bh(&msk->pm.lock);
1415 mptcp_pm_remove_addr(msk, &list);
1416 spin_unlock_bh(&msk->pm.lock);
1417 }
1418 return ret;
1419 }
1420
mptcp_nl_remove_subflow_and_signal_addr(struct net * net,const struct mptcp_pm_addr_entry * entry)1421 static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net,
1422 const struct mptcp_pm_addr_entry *entry)
1423 {
1424 const struct mptcp_addr_info *addr = &entry->addr;
1425 struct mptcp_rm_list list = { .nr = 0 };
1426 long s_slot = 0, s_num = 0;
1427 struct mptcp_sock *msk;
1428
1429 pr_debug("remove_id=%d", addr->id);
1430
1431 list.ids[list.nr++] = addr->id;
1432
1433 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) {
1434 struct sock *sk = (struct sock *)msk;
1435 bool remove_subflow;
1436
1437 if (mptcp_pm_is_userspace(msk))
1438 goto next;
1439
1440 if (list_empty(&msk->conn_list)) {
1441 mptcp_pm_remove_anno_addr(msk, addr, false);
1442 goto next;
1443 }
1444
1445 lock_sock(sk);
1446 remove_subflow = lookup_subflow_by_saddr(&msk->conn_list, addr);
1447 mptcp_pm_remove_anno_addr(msk, addr, remove_subflow &&
1448 !(entry->flags & MPTCP_PM_ADDR_FLAG_IMPLICIT));
1449 if (remove_subflow)
1450 mptcp_pm_remove_subflow(msk, &list);
1451 release_sock(sk);
1452
1453 next:
1454 sock_put(sk);
1455 cond_resched();
1456 }
1457
1458 return 0;
1459 }
1460
mptcp_nl_remove_id_zero_address(struct net * net,struct mptcp_addr_info * addr)1461 static int mptcp_nl_remove_id_zero_address(struct net *net,
1462 struct mptcp_addr_info *addr)
1463 {
1464 struct mptcp_rm_list list = { .nr = 0 };
1465 long s_slot = 0, s_num = 0;
1466 struct mptcp_sock *msk;
1467
1468 list.ids[list.nr++] = 0;
1469
1470 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) {
1471 struct sock *sk = (struct sock *)msk;
1472 struct mptcp_addr_info msk_local;
1473
1474 if (list_empty(&msk->conn_list) || mptcp_pm_is_userspace(msk))
1475 goto next;
1476
1477 local_address((struct sock_common *)msk, &msk_local);
1478 if (!mptcp_addresses_equal(&msk_local, addr, addr->port))
1479 goto next;
1480
1481 lock_sock(sk);
1482 spin_lock_bh(&msk->pm.lock);
1483 mptcp_pm_remove_addr(msk, &list);
1484 mptcp_pm_nl_rm_subflow_received(msk, &list);
1485 spin_unlock_bh(&msk->pm.lock);
1486 release_sock(sk);
1487
1488 next:
1489 sock_put(sk);
1490 cond_resched();
1491 }
1492
1493 return 0;
1494 }
1495
mptcp_nl_cmd_del_addr(struct sk_buff * skb,struct genl_info * info)1496 static int mptcp_nl_cmd_del_addr(struct sk_buff *skb, struct genl_info *info)
1497 {
1498 struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR];
1499 struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
1500 struct mptcp_pm_addr_entry addr, *entry;
1501 unsigned int addr_max;
1502 int ret;
1503
1504 ret = mptcp_pm_parse_entry(attr, info, false, &addr);
1505 if (ret < 0)
1506 return ret;
1507
1508 /* the zero id address is special: the first address used by the msk
1509 * always gets such an id, so different subflows can have different zero
1510 * id addresses. Additionally zero id is not accounted for in id_bitmap.
1511 * Let's use an 'mptcp_rm_list' instead of the common remove code.
1512 */
1513 if (addr.addr.id == 0)
1514 return mptcp_nl_remove_id_zero_address(sock_net(skb->sk), &addr.addr);
1515
1516 spin_lock_bh(&pernet->lock);
1517 entry = __lookup_addr_by_id(pernet, addr.addr.id);
1518 if (!entry) {
1519 GENL_SET_ERR_MSG(info, "address not found");
1520 spin_unlock_bh(&pernet->lock);
1521 return -EINVAL;
1522 }
1523 if (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL) {
1524 addr_max = pernet->add_addr_signal_max;
1525 WRITE_ONCE(pernet->add_addr_signal_max, addr_max - 1);
1526 }
1527 if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) {
1528 addr_max = pernet->local_addr_max;
1529 WRITE_ONCE(pernet->local_addr_max, addr_max - 1);
1530 }
1531
1532 pernet->addrs--;
1533 list_del_rcu(&entry->list);
1534 __clear_bit(entry->addr.id, pernet->id_bitmap);
1535 spin_unlock_bh(&pernet->lock);
1536
1537 mptcp_nl_remove_subflow_and_signal_addr(sock_net(skb->sk), entry);
1538 synchronize_rcu();
1539 __mptcp_pm_release_addr_entry(entry);
1540
1541 return ret;
1542 }
1543
mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock * msk,struct list_head * rm_list)1544 void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk,
1545 struct list_head *rm_list)
1546 {
1547 struct mptcp_rm_list alist = { .nr = 0 }, slist = { .nr = 0 };
1548 struct mptcp_pm_addr_entry *entry;
1549
1550 list_for_each_entry(entry, rm_list, list) {
1551 if (lookup_subflow_by_saddr(&msk->conn_list, &entry->addr) &&
1552 slist.nr < MPTCP_RM_IDS_MAX)
1553 slist.ids[slist.nr++] = entry->addr.id;
1554
1555 if (remove_anno_list_by_saddr(msk, &entry->addr) &&
1556 alist.nr < MPTCP_RM_IDS_MAX)
1557 alist.ids[alist.nr++] = entry->addr.id;
1558 }
1559
1560 if (alist.nr) {
1561 spin_lock_bh(&msk->pm.lock);
1562 mptcp_pm_remove_addr(msk, &alist);
1563 spin_unlock_bh(&msk->pm.lock);
1564 }
1565 if (slist.nr)
1566 mptcp_pm_remove_subflow(msk, &slist);
1567 }
1568
mptcp_nl_remove_addrs_list(struct net * net,struct list_head * rm_list)1569 static void mptcp_nl_remove_addrs_list(struct net *net,
1570 struct list_head *rm_list)
1571 {
1572 long s_slot = 0, s_num = 0;
1573 struct mptcp_sock *msk;
1574
1575 if (list_empty(rm_list))
1576 return;
1577
1578 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) {
1579 struct sock *sk = (struct sock *)msk;
1580
1581 if (!mptcp_pm_is_userspace(msk)) {
1582 lock_sock(sk);
1583 mptcp_pm_remove_addrs_and_subflows(msk, rm_list);
1584 release_sock(sk);
1585 }
1586
1587 sock_put(sk);
1588 cond_resched();
1589 }
1590 }
1591
1592 /* caller must ensure the RCU grace period is already elapsed */
__flush_addrs(struct list_head * list)1593 static void __flush_addrs(struct list_head *list)
1594 {
1595 while (!list_empty(list)) {
1596 struct mptcp_pm_addr_entry *cur;
1597
1598 cur = list_entry(list->next,
1599 struct mptcp_pm_addr_entry, list);
1600 list_del_rcu(&cur->list);
1601 __mptcp_pm_release_addr_entry(cur);
1602 }
1603 }
1604
__reset_counters(struct pm_nl_pernet * pernet)1605 static void __reset_counters(struct pm_nl_pernet *pernet)
1606 {
1607 WRITE_ONCE(pernet->add_addr_signal_max, 0);
1608 WRITE_ONCE(pernet->add_addr_accept_max, 0);
1609 WRITE_ONCE(pernet->local_addr_max, 0);
1610 pernet->addrs = 0;
1611 }
1612
mptcp_nl_cmd_flush_addrs(struct sk_buff * skb,struct genl_info * info)1613 static int mptcp_nl_cmd_flush_addrs(struct sk_buff *skb, struct genl_info *info)
1614 {
1615 struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
1616 LIST_HEAD(free_list);
1617
1618 spin_lock_bh(&pernet->lock);
1619 list_splice_init(&pernet->local_addr_list, &free_list);
1620 __reset_counters(pernet);
1621 pernet->next_id = 1;
1622 bitmap_zero(pernet->id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1);
1623 spin_unlock_bh(&pernet->lock);
1624 mptcp_nl_remove_addrs_list(sock_net(skb->sk), &free_list);
1625 synchronize_rcu();
1626 __flush_addrs(&free_list);
1627 return 0;
1628 }
1629
mptcp_nl_fill_addr(struct sk_buff * skb,struct mptcp_pm_addr_entry * entry)1630 static int mptcp_nl_fill_addr(struct sk_buff *skb,
1631 struct mptcp_pm_addr_entry *entry)
1632 {
1633 struct mptcp_addr_info *addr = &entry->addr;
1634 struct nlattr *attr;
1635
1636 attr = nla_nest_start(skb, MPTCP_PM_ATTR_ADDR);
1637 if (!attr)
1638 return -EMSGSIZE;
1639
1640 if (nla_put_u16(skb, MPTCP_PM_ADDR_ATTR_FAMILY, addr->family))
1641 goto nla_put_failure;
1642 if (nla_put_u16(skb, MPTCP_PM_ADDR_ATTR_PORT, ntohs(addr->port)))
1643 goto nla_put_failure;
1644 if (nla_put_u8(skb, MPTCP_PM_ADDR_ATTR_ID, addr->id))
1645 goto nla_put_failure;
1646 if (nla_put_u32(skb, MPTCP_PM_ADDR_ATTR_FLAGS, entry->flags))
1647 goto nla_put_failure;
1648 if (entry->ifindex &&
1649 nla_put_s32(skb, MPTCP_PM_ADDR_ATTR_IF_IDX, entry->ifindex))
1650 goto nla_put_failure;
1651
1652 if (addr->family == AF_INET &&
1653 nla_put_in_addr(skb, MPTCP_PM_ADDR_ATTR_ADDR4,
1654 addr->addr.s_addr))
1655 goto nla_put_failure;
1656 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
1657 else if (addr->family == AF_INET6 &&
1658 nla_put_in6_addr(skb, MPTCP_PM_ADDR_ATTR_ADDR6, &addr->addr6))
1659 goto nla_put_failure;
1660 #endif
1661 nla_nest_end(skb, attr);
1662 return 0;
1663
1664 nla_put_failure:
1665 nla_nest_cancel(skb, attr);
1666 return -EMSGSIZE;
1667 }
1668
mptcp_nl_cmd_get_addr(struct sk_buff * skb,struct genl_info * info)1669 static int mptcp_nl_cmd_get_addr(struct sk_buff *skb, struct genl_info *info)
1670 {
1671 struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR];
1672 struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
1673 struct mptcp_pm_addr_entry addr, *entry;
1674 struct sk_buff *msg;
1675 void *reply;
1676 int ret;
1677
1678 ret = mptcp_pm_parse_entry(attr, info, false, &addr);
1679 if (ret < 0)
1680 return ret;
1681
1682 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1683 if (!msg)
1684 return -ENOMEM;
1685
1686 reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0,
1687 info->genlhdr->cmd);
1688 if (!reply) {
1689 GENL_SET_ERR_MSG(info, "not enough space in Netlink message");
1690 ret = -EMSGSIZE;
1691 goto fail;
1692 }
1693
1694 spin_lock_bh(&pernet->lock);
1695 entry = __lookup_addr_by_id(pernet, addr.addr.id);
1696 if (!entry) {
1697 GENL_SET_ERR_MSG(info, "address not found");
1698 ret = -EINVAL;
1699 goto unlock_fail;
1700 }
1701
1702 ret = mptcp_nl_fill_addr(msg, entry);
1703 if (ret)
1704 goto unlock_fail;
1705
1706 genlmsg_end(msg, reply);
1707 ret = genlmsg_reply(msg, info);
1708 spin_unlock_bh(&pernet->lock);
1709 return ret;
1710
1711 unlock_fail:
1712 spin_unlock_bh(&pernet->lock);
1713
1714 fail:
1715 nlmsg_free(msg);
1716 return ret;
1717 }
1718
mptcp_nl_cmd_dump_addrs(struct sk_buff * msg,struct netlink_callback * cb)1719 static int mptcp_nl_cmd_dump_addrs(struct sk_buff *msg,
1720 struct netlink_callback *cb)
1721 {
1722 struct net *net = sock_net(msg->sk);
1723 struct mptcp_pm_addr_entry *entry;
1724 struct pm_nl_pernet *pernet;
1725 int id = cb->args[0];
1726 void *hdr;
1727 int i;
1728
1729 pernet = pm_nl_get_pernet(net);
1730
1731 spin_lock_bh(&pernet->lock);
1732 for (i = id; i < MPTCP_PM_MAX_ADDR_ID + 1; i++) {
1733 if (test_bit(i, pernet->id_bitmap)) {
1734 entry = __lookup_addr_by_id(pernet, i);
1735 if (!entry)
1736 break;
1737
1738 if (entry->addr.id <= id)
1739 continue;
1740
1741 hdr = genlmsg_put(msg, NETLINK_CB(cb->skb).portid,
1742 cb->nlh->nlmsg_seq, &mptcp_genl_family,
1743 NLM_F_MULTI, MPTCP_PM_CMD_GET_ADDR);
1744 if (!hdr)
1745 break;
1746
1747 if (mptcp_nl_fill_addr(msg, entry) < 0) {
1748 genlmsg_cancel(msg, hdr);
1749 break;
1750 }
1751
1752 id = entry->addr.id;
1753 genlmsg_end(msg, hdr);
1754 }
1755 }
1756 spin_unlock_bh(&pernet->lock);
1757
1758 cb->args[0] = id;
1759 return msg->len;
1760 }
1761
parse_limit(struct genl_info * info,int id,unsigned int * limit)1762 static int parse_limit(struct genl_info *info, int id, unsigned int *limit)
1763 {
1764 struct nlattr *attr = info->attrs[id];
1765
1766 if (!attr)
1767 return 0;
1768
1769 *limit = nla_get_u32(attr);
1770 if (*limit > MPTCP_PM_ADDR_MAX) {
1771 GENL_SET_ERR_MSG(info, "limit greater than maximum");
1772 return -EINVAL;
1773 }
1774 return 0;
1775 }
1776
1777 static int
mptcp_nl_cmd_set_limits(struct sk_buff * skb,struct genl_info * info)1778 mptcp_nl_cmd_set_limits(struct sk_buff *skb, struct genl_info *info)
1779 {
1780 struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
1781 unsigned int rcv_addrs, subflows;
1782 int ret;
1783
1784 spin_lock_bh(&pernet->lock);
1785 rcv_addrs = pernet->add_addr_accept_max;
1786 ret = parse_limit(info, MPTCP_PM_ATTR_RCV_ADD_ADDRS, &rcv_addrs);
1787 if (ret)
1788 goto unlock;
1789
1790 subflows = pernet->subflows_max;
1791 ret = parse_limit(info, MPTCP_PM_ATTR_SUBFLOWS, &subflows);
1792 if (ret)
1793 goto unlock;
1794
1795 WRITE_ONCE(pernet->add_addr_accept_max, rcv_addrs);
1796 WRITE_ONCE(pernet->subflows_max, subflows);
1797
1798 unlock:
1799 spin_unlock_bh(&pernet->lock);
1800 return ret;
1801 }
1802
1803 static int
mptcp_nl_cmd_get_limits(struct sk_buff * skb,struct genl_info * info)1804 mptcp_nl_cmd_get_limits(struct sk_buff *skb, struct genl_info *info)
1805 {
1806 struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
1807 struct sk_buff *msg;
1808 void *reply;
1809
1810 msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1811 if (!msg)
1812 return -ENOMEM;
1813
1814 reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0,
1815 MPTCP_PM_CMD_GET_LIMITS);
1816 if (!reply)
1817 goto fail;
1818
1819 if (nla_put_u32(msg, MPTCP_PM_ATTR_RCV_ADD_ADDRS,
1820 READ_ONCE(pernet->add_addr_accept_max)))
1821 goto fail;
1822
1823 if (nla_put_u32(msg, MPTCP_PM_ATTR_SUBFLOWS,
1824 READ_ONCE(pernet->subflows_max)))
1825 goto fail;
1826
1827 genlmsg_end(msg, reply);
1828 return genlmsg_reply(msg, info);
1829
1830 fail:
1831 GENL_SET_ERR_MSG(info, "not enough space in Netlink message");
1832 nlmsg_free(msg);
1833 return -EMSGSIZE;
1834 }
1835
mptcp_pm_nl_fullmesh(struct mptcp_sock * msk,struct mptcp_addr_info * addr)1836 static void mptcp_pm_nl_fullmesh(struct mptcp_sock *msk,
1837 struct mptcp_addr_info *addr)
1838 {
1839 struct mptcp_rm_list list = { .nr = 0 };
1840
1841 list.ids[list.nr++] = addr->id;
1842
1843 spin_lock_bh(&msk->pm.lock);
1844 mptcp_pm_nl_rm_subflow_received(msk, &list);
1845 mptcp_pm_create_subflow_or_signal_addr(msk);
1846 spin_unlock_bh(&msk->pm.lock);
1847 }
1848
mptcp_nl_set_flags(struct net * net,struct mptcp_addr_info * addr,u8 bkup,u8 changed)1849 static int mptcp_nl_set_flags(struct net *net,
1850 struct mptcp_addr_info *addr,
1851 u8 bkup, u8 changed)
1852 {
1853 long s_slot = 0, s_num = 0;
1854 struct mptcp_sock *msk;
1855 int ret = -EINVAL;
1856
1857 while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) {
1858 struct sock *sk = (struct sock *)msk;
1859
1860 if (list_empty(&msk->conn_list) || mptcp_pm_is_userspace(msk))
1861 goto next;
1862
1863 lock_sock(sk);
1864 if (changed & MPTCP_PM_ADDR_FLAG_BACKUP)
1865 ret = mptcp_pm_nl_mp_prio_send_ack(msk, addr, NULL, bkup);
1866 if (changed & MPTCP_PM_ADDR_FLAG_FULLMESH)
1867 mptcp_pm_nl_fullmesh(msk, addr);
1868 release_sock(sk);
1869
1870 next:
1871 sock_put(sk);
1872 cond_resched();
1873 }
1874
1875 return ret;
1876 }
1877
mptcp_nl_cmd_set_flags(struct sk_buff * skb,struct genl_info * info)1878 static int mptcp_nl_cmd_set_flags(struct sk_buff *skb, struct genl_info *info)
1879 {
1880 struct mptcp_pm_addr_entry addr = { .addr = { .family = AF_UNSPEC }, }, *entry;
1881 struct mptcp_pm_addr_entry remote = { .addr = { .family = AF_UNSPEC }, };
1882 struct nlattr *attr_rem = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE];
1883 struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN];
1884 struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR];
1885 struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
1886 u8 changed, mask = MPTCP_PM_ADDR_FLAG_BACKUP |
1887 MPTCP_PM_ADDR_FLAG_FULLMESH;
1888 struct net *net = sock_net(skb->sk);
1889 u8 bkup = 0, lookup_by_id = 0;
1890 int ret;
1891
1892 ret = mptcp_pm_parse_entry(attr, info, false, &addr);
1893 if (ret < 0)
1894 return ret;
1895
1896 if (attr_rem) {
1897 ret = mptcp_pm_parse_entry(attr_rem, info, false, &remote);
1898 if (ret < 0)
1899 return ret;
1900 }
1901
1902 if (addr.flags & MPTCP_PM_ADDR_FLAG_BACKUP)
1903 bkup = 1;
1904 if (addr.addr.family == AF_UNSPEC) {
1905 lookup_by_id = 1;
1906 if (!addr.addr.id)
1907 return -EOPNOTSUPP;
1908 }
1909
1910 if (token)
1911 return mptcp_userspace_pm_set_flags(sock_net(skb->sk),
1912 token, &addr, &remote, bkup);
1913
1914 spin_lock_bh(&pernet->lock);
1915 entry = __lookup_addr(pernet, &addr.addr, lookup_by_id);
1916 if (!entry) {
1917 spin_unlock_bh(&pernet->lock);
1918 return -EINVAL;
1919 }
1920 if ((addr.flags & MPTCP_PM_ADDR_FLAG_FULLMESH) &&
1921 (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) {
1922 spin_unlock_bh(&pernet->lock);
1923 return -EINVAL;
1924 }
1925
1926 changed = (addr.flags ^ entry->flags) & mask;
1927 entry->flags = (entry->flags & ~mask) | (addr.flags & mask);
1928 addr = *entry;
1929 spin_unlock_bh(&pernet->lock);
1930
1931 mptcp_nl_set_flags(net, &addr.addr, bkup, changed);
1932 return 0;
1933 }
1934
mptcp_nl_mcast_send(struct net * net,struct sk_buff * nlskb,gfp_t gfp)1935 static void mptcp_nl_mcast_send(struct net *net, struct sk_buff *nlskb, gfp_t gfp)
1936 {
1937 genlmsg_multicast_netns(&mptcp_genl_family, net,
1938 nlskb, 0, MPTCP_PM_EV_GRP_OFFSET, gfp);
1939 }
1940
mptcp_userspace_pm_active(const struct mptcp_sock * msk)1941 bool mptcp_userspace_pm_active(const struct mptcp_sock *msk)
1942 {
1943 return genl_has_listeners(&mptcp_genl_family,
1944 sock_net((const struct sock *)msk),
1945 MPTCP_PM_EV_GRP_OFFSET);
1946 }
1947
mptcp_event_add_subflow(struct sk_buff * skb,const struct sock * ssk)1948 static int mptcp_event_add_subflow(struct sk_buff *skb, const struct sock *ssk)
1949 {
1950 const struct inet_sock *issk = inet_sk(ssk);
1951 const struct mptcp_subflow_context *sf;
1952
1953 if (nla_put_u16(skb, MPTCP_ATTR_FAMILY, ssk->sk_family))
1954 return -EMSGSIZE;
1955
1956 switch (ssk->sk_family) {
1957 case AF_INET:
1958 if (nla_put_in_addr(skb, MPTCP_ATTR_SADDR4, issk->inet_saddr))
1959 return -EMSGSIZE;
1960 if (nla_put_in_addr(skb, MPTCP_ATTR_DADDR4, issk->inet_daddr))
1961 return -EMSGSIZE;
1962 break;
1963 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
1964 case AF_INET6: {
1965 const struct ipv6_pinfo *np = inet6_sk(ssk);
1966
1967 if (nla_put_in6_addr(skb, MPTCP_ATTR_SADDR6, &np->saddr))
1968 return -EMSGSIZE;
1969 if (nla_put_in6_addr(skb, MPTCP_ATTR_DADDR6, &ssk->sk_v6_daddr))
1970 return -EMSGSIZE;
1971 break;
1972 }
1973 #endif
1974 default:
1975 WARN_ON_ONCE(1);
1976 return -EMSGSIZE;
1977 }
1978
1979 if (nla_put_be16(skb, MPTCP_ATTR_SPORT, issk->inet_sport))
1980 return -EMSGSIZE;
1981 if (nla_put_be16(skb, MPTCP_ATTR_DPORT, issk->inet_dport))
1982 return -EMSGSIZE;
1983
1984 sf = mptcp_subflow_ctx(ssk);
1985 if (WARN_ON_ONCE(!sf))
1986 return -EINVAL;
1987
1988 if (nla_put_u8(skb, MPTCP_ATTR_LOC_ID, sf->local_id))
1989 return -EMSGSIZE;
1990
1991 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, sf->remote_id))
1992 return -EMSGSIZE;
1993
1994 return 0;
1995 }
1996
mptcp_event_put_token_and_ssk(struct sk_buff * skb,const struct mptcp_sock * msk,const struct sock * ssk)1997 static int mptcp_event_put_token_and_ssk(struct sk_buff *skb,
1998 const struct mptcp_sock *msk,
1999 const struct sock *ssk)
2000 {
2001 const struct sock *sk = (const struct sock *)msk;
2002 const struct mptcp_subflow_context *sf;
2003 u8 sk_err;
2004
2005 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token))
2006 return -EMSGSIZE;
2007
2008 if (mptcp_event_add_subflow(skb, ssk))
2009 return -EMSGSIZE;
2010
2011 sf = mptcp_subflow_ctx(ssk);
2012 if (WARN_ON_ONCE(!sf))
2013 return -EINVAL;
2014
2015 if (nla_put_u8(skb, MPTCP_ATTR_BACKUP, sf->backup))
2016 return -EMSGSIZE;
2017
2018 if (ssk->sk_bound_dev_if &&
2019 nla_put_s32(skb, MPTCP_ATTR_IF_IDX, ssk->sk_bound_dev_if))
2020 return -EMSGSIZE;
2021
2022 sk_err = ssk->sk_err;
2023 if (sk_err && sk->sk_state == TCP_ESTABLISHED &&
2024 nla_put_u8(skb, MPTCP_ATTR_ERROR, sk_err))
2025 return -EMSGSIZE;
2026
2027 return 0;
2028 }
2029
mptcp_event_sub_established(struct sk_buff * skb,const struct mptcp_sock * msk,const struct sock * ssk)2030 static int mptcp_event_sub_established(struct sk_buff *skb,
2031 const struct mptcp_sock *msk,
2032 const struct sock *ssk)
2033 {
2034 return mptcp_event_put_token_and_ssk(skb, msk, ssk);
2035 }
2036
mptcp_event_sub_closed(struct sk_buff * skb,const struct mptcp_sock * msk,const struct sock * ssk)2037 static int mptcp_event_sub_closed(struct sk_buff *skb,
2038 const struct mptcp_sock *msk,
2039 const struct sock *ssk)
2040 {
2041 const struct mptcp_subflow_context *sf;
2042
2043 if (mptcp_event_put_token_and_ssk(skb, msk, ssk))
2044 return -EMSGSIZE;
2045
2046 sf = mptcp_subflow_ctx(ssk);
2047 if (!sf->reset_seen)
2048 return 0;
2049
2050 if (nla_put_u32(skb, MPTCP_ATTR_RESET_REASON, sf->reset_reason))
2051 return -EMSGSIZE;
2052
2053 if (nla_put_u32(skb, MPTCP_ATTR_RESET_FLAGS, sf->reset_transient))
2054 return -EMSGSIZE;
2055
2056 return 0;
2057 }
2058
mptcp_event_created(struct sk_buff * skb,const struct mptcp_sock * msk,const struct sock * ssk)2059 static int mptcp_event_created(struct sk_buff *skb,
2060 const struct mptcp_sock *msk,
2061 const struct sock *ssk)
2062 {
2063 int err = nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token);
2064
2065 if (err)
2066 return err;
2067
2068 if (nla_put_u8(skb, MPTCP_ATTR_SERVER_SIDE, READ_ONCE(msk->pm.server_side)))
2069 return -EMSGSIZE;
2070
2071 return mptcp_event_add_subflow(skb, ssk);
2072 }
2073
mptcp_event_addr_removed(const struct mptcp_sock * msk,uint8_t id)2074 void mptcp_event_addr_removed(const struct mptcp_sock *msk, uint8_t id)
2075 {
2076 struct net *net = sock_net((const struct sock *)msk);
2077 struct nlmsghdr *nlh;
2078 struct sk_buff *skb;
2079
2080 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET))
2081 return;
2082
2083 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
2084 if (!skb)
2085 return;
2086
2087 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, MPTCP_EVENT_REMOVED);
2088 if (!nlh)
2089 goto nla_put_failure;
2090
2091 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token))
2092 goto nla_put_failure;
2093
2094 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, id))
2095 goto nla_put_failure;
2096
2097 genlmsg_end(skb, nlh);
2098 mptcp_nl_mcast_send(net, skb, GFP_ATOMIC);
2099 return;
2100
2101 nla_put_failure:
2102 kfree_skb(skb);
2103 }
2104
mptcp_event_addr_announced(const struct sock * ssk,const struct mptcp_addr_info * info)2105 void mptcp_event_addr_announced(const struct sock *ssk,
2106 const struct mptcp_addr_info *info)
2107 {
2108 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
2109 struct mptcp_sock *msk = mptcp_sk(subflow->conn);
2110 struct net *net = sock_net(ssk);
2111 struct nlmsghdr *nlh;
2112 struct sk_buff *skb;
2113
2114 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET))
2115 return;
2116
2117 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
2118 if (!skb)
2119 return;
2120
2121 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0,
2122 MPTCP_EVENT_ANNOUNCED);
2123 if (!nlh)
2124 goto nla_put_failure;
2125
2126 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token))
2127 goto nla_put_failure;
2128
2129 if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, info->id))
2130 goto nla_put_failure;
2131
2132 if (nla_put_be16(skb, MPTCP_ATTR_DPORT,
2133 info->port == 0 ?
2134 inet_sk(ssk)->inet_dport :
2135 info->port))
2136 goto nla_put_failure;
2137
2138 switch (info->family) {
2139 case AF_INET:
2140 if (nla_put_in_addr(skb, MPTCP_ATTR_DADDR4, info->addr.s_addr))
2141 goto nla_put_failure;
2142 break;
2143 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
2144 case AF_INET6:
2145 if (nla_put_in6_addr(skb, MPTCP_ATTR_DADDR6, &info->addr6))
2146 goto nla_put_failure;
2147 break;
2148 #endif
2149 default:
2150 WARN_ON_ONCE(1);
2151 goto nla_put_failure;
2152 }
2153
2154 genlmsg_end(skb, nlh);
2155 mptcp_nl_mcast_send(net, skb, GFP_ATOMIC);
2156 return;
2157
2158 nla_put_failure:
2159 kfree_skb(skb);
2160 }
2161
mptcp_event(enum mptcp_event_type type,const struct mptcp_sock * msk,const struct sock * ssk,gfp_t gfp)2162 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk,
2163 const struct sock *ssk, gfp_t gfp)
2164 {
2165 struct net *net = sock_net((const struct sock *)msk);
2166 struct nlmsghdr *nlh;
2167 struct sk_buff *skb;
2168
2169 if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET))
2170 return;
2171
2172 skb = nlmsg_new(NLMSG_DEFAULT_SIZE, gfp);
2173 if (!skb)
2174 return;
2175
2176 nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, type);
2177 if (!nlh)
2178 goto nla_put_failure;
2179
2180 switch (type) {
2181 case MPTCP_EVENT_UNSPEC:
2182 WARN_ON_ONCE(1);
2183 break;
2184 case MPTCP_EVENT_CREATED:
2185 case MPTCP_EVENT_ESTABLISHED:
2186 if (mptcp_event_created(skb, msk, ssk) < 0)
2187 goto nla_put_failure;
2188 break;
2189 case MPTCP_EVENT_CLOSED:
2190 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token) < 0)
2191 goto nla_put_failure;
2192 break;
2193 case MPTCP_EVENT_ANNOUNCED:
2194 case MPTCP_EVENT_REMOVED:
2195 /* call mptcp_event_addr_announced()/removed instead */
2196 WARN_ON_ONCE(1);
2197 break;
2198 case MPTCP_EVENT_SUB_ESTABLISHED:
2199 case MPTCP_EVENT_SUB_PRIORITY:
2200 if (mptcp_event_sub_established(skb, msk, ssk) < 0)
2201 goto nla_put_failure;
2202 break;
2203 case MPTCP_EVENT_SUB_CLOSED:
2204 if (mptcp_event_sub_closed(skb, msk, ssk) < 0)
2205 goto nla_put_failure;
2206 break;
2207 }
2208
2209 genlmsg_end(skb, nlh);
2210 mptcp_nl_mcast_send(net, skb, gfp);
2211 return;
2212
2213 nla_put_failure:
2214 kfree_skb(skb);
2215 }
2216
2217 static const struct genl_small_ops mptcp_pm_ops[] = {
2218 {
2219 .cmd = MPTCP_PM_CMD_ADD_ADDR,
2220 .doit = mptcp_nl_cmd_add_addr,
2221 .flags = GENL_UNS_ADMIN_PERM,
2222 },
2223 {
2224 .cmd = MPTCP_PM_CMD_DEL_ADDR,
2225 .doit = mptcp_nl_cmd_del_addr,
2226 .flags = GENL_UNS_ADMIN_PERM,
2227 },
2228 {
2229 .cmd = MPTCP_PM_CMD_FLUSH_ADDRS,
2230 .doit = mptcp_nl_cmd_flush_addrs,
2231 .flags = GENL_UNS_ADMIN_PERM,
2232 },
2233 {
2234 .cmd = MPTCP_PM_CMD_GET_ADDR,
2235 .doit = mptcp_nl_cmd_get_addr,
2236 .dumpit = mptcp_nl_cmd_dump_addrs,
2237 },
2238 {
2239 .cmd = MPTCP_PM_CMD_SET_LIMITS,
2240 .doit = mptcp_nl_cmd_set_limits,
2241 .flags = GENL_UNS_ADMIN_PERM,
2242 },
2243 {
2244 .cmd = MPTCP_PM_CMD_GET_LIMITS,
2245 .doit = mptcp_nl_cmd_get_limits,
2246 },
2247 {
2248 .cmd = MPTCP_PM_CMD_SET_FLAGS,
2249 .doit = mptcp_nl_cmd_set_flags,
2250 .flags = GENL_UNS_ADMIN_PERM,
2251 },
2252 {
2253 .cmd = MPTCP_PM_CMD_ANNOUNCE,
2254 .doit = mptcp_nl_cmd_announce,
2255 .flags = GENL_UNS_ADMIN_PERM,
2256 },
2257 {
2258 .cmd = MPTCP_PM_CMD_REMOVE,
2259 .doit = mptcp_nl_cmd_remove,
2260 .flags = GENL_UNS_ADMIN_PERM,
2261 },
2262 {
2263 .cmd = MPTCP_PM_CMD_SUBFLOW_CREATE,
2264 .doit = mptcp_nl_cmd_sf_create,
2265 .flags = GENL_UNS_ADMIN_PERM,
2266 },
2267 {
2268 .cmd = MPTCP_PM_CMD_SUBFLOW_DESTROY,
2269 .doit = mptcp_nl_cmd_sf_destroy,
2270 .flags = GENL_UNS_ADMIN_PERM,
2271 },
2272 };
2273
2274 static struct genl_family mptcp_genl_family __ro_after_init = {
2275 .name = MPTCP_PM_NAME,
2276 .version = MPTCP_PM_VER,
2277 .maxattr = MPTCP_PM_ATTR_MAX,
2278 .policy = mptcp_pm_policy,
2279 .netnsok = true,
2280 .module = THIS_MODULE,
2281 .small_ops = mptcp_pm_ops,
2282 .n_small_ops = ARRAY_SIZE(mptcp_pm_ops),
2283 .resv_start_op = MPTCP_PM_CMD_SUBFLOW_DESTROY + 1,
2284 .mcgrps = mptcp_pm_mcgrps,
2285 .n_mcgrps = ARRAY_SIZE(mptcp_pm_mcgrps),
2286 };
2287
pm_nl_init_net(struct net * net)2288 static int __net_init pm_nl_init_net(struct net *net)
2289 {
2290 struct pm_nl_pernet *pernet = pm_nl_get_pernet(net);
2291
2292 INIT_LIST_HEAD_RCU(&pernet->local_addr_list);
2293
2294 /* Cit. 2 subflows ought to be enough for anybody. */
2295 pernet->subflows_max = 2;
2296 pernet->next_id = 1;
2297 pernet->stale_loss_cnt = 4;
2298 spin_lock_init(&pernet->lock);
2299
2300 /* No need to initialize other pernet fields, the struct is zeroed at
2301 * allocation time.
2302 */
2303
2304 return 0;
2305 }
2306
pm_nl_exit_net(struct list_head * net_list)2307 static void __net_exit pm_nl_exit_net(struct list_head *net_list)
2308 {
2309 struct net *net;
2310
2311 list_for_each_entry(net, net_list, exit_list) {
2312 struct pm_nl_pernet *pernet = pm_nl_get_pernet(net);
2313
2314 /* net is removed from namespace list, can't race with
2315 * other modifiers, also netns core already waited for a
2316 * RCU grace period.
2317 */
2318 __flush_addrs(&pernet->local_addr_list);
2319 }
2320 }
2321
2322 static struct pernet_operations mptcp_pm_pernet_ops = {
2323 .init = pm_nl_init_net,
2324 .exit_batch = pm_nl_exit_net,
2325 .id = &pm_nl_pernet_id,
2326 .size = sizeof(struct pm_nl_pernet),
2327 };
2328
mptcp_pm_nl_init(void)2329 void __init mptcp_pm_nl_init(void)
2330 {
2331 if (register_pernet_subsys(&mptcp_pm_pernet_ops) < 0)
2332 panic("Failed to register MPTCP PM pernet subsystem.\n");
2333
2334 if (genl_register_family(&mptcp_genl_family))
2335 panic("Failed to register MPTCP PM netlink family\n");
2336 }
2337