1 // SPDX-License-Identifier: GPL-2.0
2 /* Multipath TCP
3 *
4 * Copyright (c) 2021, Red Hat.
5 */
6
7 #define pr_fmt(fmt) "MPTCP: " fmt
8
9 #include <linux/kernel.h>
10 #include <linux/module.h>
11 #include <net/sock.h>
12 #include <net/protocol.h>
13 #include <net/tcp.h>
14 #include <net/mptcp.h>
15 #include "protocol.h"
16
17 #define MIN_INFO_OPTLEN_SIZE 16
18 #define MIN_FULL_INFO_OPTLEN_SIZE 40
19
20 static struct sock *__mptcp_tcp_fallback(struct mptcp_sock *msk)
21 {
22 msk_owned_by_me(msk);
23
24 if (likely(!__mptcp_check_fallback(msk)))
25 return NULL;
26
27 return msk->first;
28 }
29
30 static u32 sockopt_seq_reset(const struct sock *sk)
31 {
32 sock_owned_by_me(sk);
33
34 /* Highbits contain state. Allows to distinguish sockopt_seq
35 * of listener and established:
36 * s0 = new_listener()
37 * sockopt(s0) - seq is 1
38 * s1 = accept(s0) - s1 inherits seq 1 if listener sk (s0)
39 * sockopt(s0) - seq increments to 2 on s0
40 * sockopt(s1) // seq increments to 2 on s1 (different option)
41 * new ssk completes join, inherits options from s0 // seq 2
42 * Needs sync from mptcp join logic, but ssk->seq == msk->seq
43 *
44 * Set High order bits to sk_state so ssk->seq == msk->seq test
45 * will fail.
46 */
47
48 return (u32)sk->sk_state << 24u;
49 }
50
51 static void sockopt_seq_inc(struct mptcp_sock *msk)
52 {
53 u32 seq = (msk->setsockopt_seq + 1) & 0x00ffffff;
54
55 msk->setsockopt_seq = sockopt_seq_reset((struct sock *)msk) + seq;
56 }
57
58 static int mptcp_get_int_option(struct mptcp_sock *msk, sockptr_t optval,
59 unsigned int optlen, int *val)
60 {
61 if (optlen < sizeof(int))
62 return -EINVAL;
63
64 if (copy_from_sockptr(val, optval, sizeof(*val)))
65 return -EFAULT;
66
67 return 0;
68 }
69
70 static void mptcp_sol_socket_sync_intval(struct mptcp_sock *msk, int optname, int val)
71 {
72 struct mptcp_subflow_context *subflow;
73 struct sock *sk = (struct sock *)msk;
74
75 lock_sock(sk);
76 sockopt_seq_inc(msk);
77
78 mptcp_for_each_subflow(msk, subflow) {
79 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
80 bool slow = lock_sock_fast(ssk);
81
82 switch (optname) {
83 case SO_DEBUG:
84 sock_valbool_flag(ssk, SOCK_DBG, !!val);
85 break;
86 case SO_KEEPALIVE:
87 if (ssk->sk_prot->keepalive)
88 ssk->sk_prot->keepalive(ssk, !!val);
89 sock_valbool_flag(ssk, SOCK_KEEPOPEN, !!val);
90 break;
91 case SO_PRIORITY:
92 WRITE_ONCE(ssk->sk_priority, val);
93 break;
94 case SO_SNDBUF:
95 case SO_SNDBUFFORCE:
96 ssk->sk_userlocks |= SOCK_SNDBUF_LOCK;
97 WRITE_ONCE(ssk->sk_sndbuf, sk->sk_sndbuf);
98 mptcp_subflow_ctx(ssk)->cached_sndbuf = sk->sk_sndbuf;
99 break;
100 case SO_RCVBUF:
101 case SO_RCVBUFFORCE:
102 ssk->sk_userlocks |= SOCK_RCVBUF_LOCK;
103 WRITE_ONCE(ssk->sk_rcvbuf, sk->sk_rcvbuf);
104 break;
105 case SO_MARK:
106 if (READ_ONCE(ssk->sk_mark) != sk->sk_mark) {
107 WRITE_ONCE(ssk->sk_mark, sk->sk_mark);
108 sk_dst_reset(ssk);
109 }
110 break;
111 case SO_INCOMING_CPU:
112 WRITE_ONCE(ssk->sk_incoming_cpu, val);
113 break;
114 }
115
116 subflow->setsockopt_seq = msk->setsockopt_seq;
117 unlock_sock_fast(ssk, slow);
118 }
119
120 release_sock(sk);
121 }
122
123 static int mptcp_sol_socket_intval(struct mptcp_sock *msk, int optname, int val)
124 {
125 sockptr_t optval = KERNEL_SOCKPTR(&val);
126 struct sock *sk = (struct sock *)msk;
127 int ret;
128
129 ret = sock_setsockopt(sk->sk_socket, SOL_SOCKET, optname,
130 optval, sizeof(val));
131 if (ret)
132 return ret;
133
134 mptcp_sol_socket_sync_intval(msk, optname, val);
135 return 0;
136 }
137
138 static void mptcp_so_incoming_cpu(struct mptcp_sock *msk, int val)
139 {
140 struct sock *sk = (struct sock *)msk;
141
142 WRITE_ONCE(sk->sk_incoming_cpu, val);
143
144 mptcp_sol_socket_sync_intval(msk, SO_INCOMING_CPU, val);
145 }
146
147 static int mptcp_setsockopt_sol_socket_tstamp(struct mptcp_sock *msk, int optname, int val)
148 {
149 sockptr_t optval = KERNEL_SOCKPTR(&val);
150 struct mptcp_subflow_context *subflow;
151 struct sock *sk = (struct sock *)msk;
152 int ret;
153
154 ret = sock_setsockopt(sk->sk_socket, SOL_SOCKET, optname,
155 optval, sizeof(val));
156 if (ret)
157 return ret;
158
159 lock_sock(sk);
160 mptcp_for_each_subflow(msk, subflow) {
161 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
162 bool slow = lock_sock_fast(ssk);
163
164 sock_set_timestamp(sk, optname, !!val);
165 unlock_sock_fast(ssk, slow);
166 }
167
168 release_sock(sk);
169 return 0;
170 }
171
172 static int mptcp_setsockopt_sol_socket_int(struct mptcp_sock *msk, int optname,
173 sockptr_t optval,
174 unsigned int optlen)
175 {
176 int val, ret;
177
178 ret = mptcp_get_int_option(msk, optval, optlen, &val);
179 if (ret)
180 return ret;
181
182 switch (optname) {
183 case SO_KEEPALIVE:
184 case SO_DEBUG:
185 case SO_MARK:
186 case SO_PRIORITY:
187 case SO_SNDBUF:
188 case SO_SNDBUFFORCE:
189 case SO_RCVBUF:
190 case SO_RCVBUFFORCE:
191 return mptcp_sol_socket_intval(msk, optname, val);
192 case SO_INCOMING_CPU:
193 mptcp_so_incoming_cpu(msk, val);
194 return 0;
195 case SO_TIMESTAMP_OLD:
196 case SO_TIMESTAMP_NEW:
197 case SO_TIMESTAMPNS_OLD:
198 case SO_TIMESTAMPNS_NEW:
199 return mptcp_setsockopt_sol_socket_tstamp(msk, optname, val);
200 }
201
202 return -ENOPROTOOPT;
203 }
204
205 static int mptcp_setsockopt_sol_socket_timestamping(struct mptcp_sock *msk,
206 int optname,
207 sockptr_t optval,
208 unsigned int optlen)
209 {
210 struct mptcp_subflow_context *subflow;
211 struct sock *sk = (struct sock *)msk;
212 struct so_timestamping timestamping;
213 int ret;
214
215 if (optlen == sizeof(timestamping)) {
216 if (copy_from_sockptr(×tamping, optval,
217 sizeof(timestamping)))
218 return -EFAULT;
219 } else if (optlen == sizeof(int)) {
220 memset(×tamping, 0, sizeof(timestamping));
221
222 if (copy_from_sockptr(×tamping.flags, optval, sizeof(int)))
223 return -EFAULT;
224 } else {
225 return -EINVAL;
226 }
227
228 ret = sock_setsockopt(sk->sk_socket, SOL_SOCKET, optname,
229 KERNEL_SOCKPTR(×tamping),
230 sizeof(timestamping));
231 if (ret)
232 return ret;
233
234 lock_sock(sk);
235
236 mptcp_for_each_subflow(msk, subflow) {
237 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
238 bool slow = lock_sock_fast(ssk);
239
240 sock_set_timestamping(sk, optname, timestamping);
241 unlock_sock_fast(ssk, slow);
242 }
243
244 release_sock(sk);
245
246 return 0;
247 }
248
249 static int mptcp_setsockopt_sol_socket_linger(struct mptcp_sock *msk, sockptr_t optval,
250 unsigned int optlen)
251 {
252 struct mptcp_subflow_context *subflow;
253 struct sock *sk = (struct sock *)msk;
254 struct linger ling;
255 sockptr_t kopt;
256 int ret;
257
258 if (optlen < sizeof(ling))
259 return -EINVAL;
260
261 if (copy_from_sockptr(&ling, optval, sizeof(ling)))
262 return -EFAULT;
263
264 kopt = KERNEL_SOCKPTR(&ling);
265 ret = sock_setsockopt(sk->sk_socket, SOL_SOCKET, SO_LINGER, kopt, sizeof(ling));
266 if (ret)
267 return ret;
268
269 lock_sock(sk);
270 sockopt_seq_inc(msk);
271 mptcp_for_each_subflow(msk, subflow) {
272 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
273 bool slow = lock_sock_fast(ssk);
274
275 if (!ling.l_onoff) {
276 sock_reset_flag(ssk, SOCK_LINGER);
277 } else {
278 ssk->sk_lingertime = sk->sk_lingertime;
279 sock_set_flag(ssk, SOCK_LINGER);
280 }
281
282 subflow->setsockopt_seq = msk->setsockopt_seq;
283 unlock_sock_fast(ssk, slow);
284 }
285
286 release_sock(sk);
287 return 0;
288 }
289
290 static int mptcp_setsockopt_sol_socket(struct mptcp_sock *msk, int optname,
291 sockptr_t optval, unsigned int optlen)
292 {
293 struct sock *sk = (struct sock *)msk;
294 struct sock *ssk;
295 int ret;
296
297 switch (optname) {
298 case SO_REUSEPORT:
299 case SO_REUSEADDR:
300 case SO_BINDTODEVICE:
301 case SO_BINDTOIFINDEX:
302 lock_sock(sk);
303 ssk = __mptcp_nmpc_sk(msk);
304 if (IS_ERR(ssk)) {
305 release_sock(sk);
306 return PTR_ERR(ssk);
307 }
308
309 ret = sk_setsockopt(ssk, SOL_SOCKET, optname, optval, optlen);
310 if (ret == 0) {
311 if (optname == SO_REUSEPORT)
312 sk->sk_reuseport = ssk->sk_reuseport;
313 else if (optname == SO_REUSEADDR)
314 sk->sk_reuse = ssk->sk_reuse;
315 else if (optname == SO_BINDTODEVICE)
316 sk->sk_bound_dev_if = ssk->sk_bound_dev_if;
317 else if (optname == SO_BINDTOIFINDEX)
318 sk->sk_bound_dev_if = ssk->sk_bound_dev_if;
319 }
320 release_sock(sk);
321 return ret;
322 case SO_KEEPALIVE:
323 case SO_PRIORITY:
324 case SO_SNDBUF:
325 case SO_SNDBUFFORCE:
326 case SO_RCVBUF:
327 case SO_RCVBUFFORCE:
328 case SO_MARK:
329 case SO_INCOMING_CPU:
330 case SO_DEBUG:
331 case SO_TIMESTAMP_OLD:
332 case SO_TIMESTAMP_NEW:
333 case SO_TIMESTAMPNS_OLD:
334 case SO_TIMESTAMPNS_NEW:
335 return mptcp_setsockopt_sol_socket_int(msk, optname, optval,
336 optlen);
337 case SO_TIMESTAMPING_OLD:
338 case SO_TIMESTAMPING_NEW:
339 return mptcp_setsockopt_sol_socket_timestamping(msk, optname,
340 optval, optlen);
341 case SO_LINGER:
342 return mptcp_setsockopt_sol_socket_linger(msk, optval, optlen);
343 case SO_RCVLOWAT:
344 case SO_RCVTIMEO_OLD:
345 case SO_RCVTIMEO_NEW:
346 case SO_SNDTIMEO_OLD:
347 case SO_SNDTIMEO_NEW:
348 case SO_BUSY_POLL:
349 case SO_PREFER_BUSY_POLL:
350 case SO_BUSY_POLL_BUDGET:
351 /* No need to copy: only relevant for msk */
352 return sock_setsockopt(sk->sk_socket, SOL_SOCKET, optname, optval, optlen);
353 case SO_NO_CHECK:
354 case SO_DONTROUTE:
355 case SO_BROADCAST:
356 case SO_BSDCOMPAT:
357 case SO_PASSCRED:
358 case SO_PASSPIDFD:
359 case SO_PASSSEC:
360 case SO_RXQ_OVFL:
361 case SO_WIFI_STATUS:
362 case SO_NOFCS:
363 case SO_SELECT_ERR_QUEUE:
364 return 0;
365 }
366
367 /* SO_OOBINLINE is not supported, let's avoid the related mess
368 * SO_ATTACH_FILTER, SO_ATTACH_BPF, SO_ATTACH_REUSEPORT_CBPF,
369 * SO_DETACH_REUSEPORT_BPF, SO_DETACH_FILTER, SO_LOCK_FILTER,
370 * we must be careful with subflows
371 *
372 * SO_ATTACH_REUSEPORT_EBPF is not supported, at it checks
373 * explicitly the sk_protocol field
374 *
375 * SO_PEEK_OFF is unsupported, as it is for plain TCP
376 * SO_MAX_PACING_RATE is unsupported, we must be careful with subflows
377 * SO_CNX_ADVICE is currently unsupported, could possibly be relevant,
378 * but likely needs careful design
379 *
380 * SO_ZEROCOPY is currently unsupported, TODO in sndmsg
381 * SO_TXTIME is currently unsupported
382 */
383
384 return -EOPNOTSUPP;
385 }
386
387 static int mptcp_setsockopt_v6(struct mptcp_sock *msk, int optname,
388 sockptr_t optval, unsigned int optlen)
389 {
390 struct sock *sk = (struct sock *)msk;
391 int ret = -EOPNOTSUPP;
392 struct sock *ssk;
393
394 switch (optname) {
395 case IPV6_V6ONLY:
396 case IPV6_TRANSPARENT:
397 case IPV6_FREEBIND:
398 lock_sock(sk);
399 ssk = __mptcp_nmpc_sk(msk);
400 if (IS_ERR(ssk)) {
401 release_sock(sk);
402 return PTR_ERR(ssk);
403 }
404
405 ret = tcp_setsockopt(ssk, SOL_IPV6, optname, optval, optlen);
406 if (ret != 0) {
407 release_sock(sk);
408 return ret;
409 }
410
411 sockopt_seq_inc(msk);
412
413 switch (optname) {
414 case IPV6_V6ONLY:
415 sk->sk_ipv6only = ssk->sk_ipv6only;
416 break;
417 case IPV6_TRANSPARENT:
418 inet_assign_bit(TRANSPARENT, sk,
419 inet_test_bit(TRANSPARENT, ssk));
420 break;
421 case IPV6_FREEBIND:
422 inet_assign_bit(FREEBIND, sk,
423 inet_test_bit(FREEBIND, ssk));
424 break;
425 }
426
427 release_sock(sk);
428 break;
429 }
430
431 return ret;
432 }
433
434 static bool mptcp_supported_sockopt(int level, int optname)
435 {
436 if (level == SOL_IP) {
437 switch (optname) {
438 /* should work fine */
439 case IP_FREEBIND:
440 case IP_TRANSPARENT:
441 case IP_BIND_ADDRESS_NO_PORT:
442 case IP_LOCAL_PORT_RANGE:
443
444 /* the following are control cmsg related */
445 case IP_PKTINFO:
446 case IP_RECVTTL:
447 case IP_RECVTOS:
448 case IP_RECVOPTS:
449 case IP_RETOPTS:
450 case IP_PASSSEC:
451 case IP_RECVORIGDSTADDR:
452 case IP_CHECKSUM:
453 case IP_RECVFRAGSIZE:
454
455 /* common stuff that need some love */
456 case IP_TOS:
457 case IP_TTL:
458 case IP_MTU_DISCOVER:
459 case IP_RECVERR:
460
461 /* possibly less common may deserve some love */
462 case IP_MINTTL:
463
464 /* the following is apparently a no-op for plain TCP */
465 case IP_RECVERR_RFC4884:
466 return true;
467 }
468
469 /* IP_OPTIONS is not supported, needs subflow care */
470 /* IP_HDRINCL, IP_NODEFRAG are not supported, RAW specific */
471 /* IP_MULTICAST_TTL, IP_MULTICAST_LOOP, IP_UNICAST_IF,
472 * IP_ADD_MEMBERSHIP, IP_ADD_SOURCE_MEMBERSHIP, IP_DROP_MEMBERSHIP,
473 * IP_DROP_SOURCE_MEMBERSHIP, IP_BLOCK_SOURCE, IP_UNBLOCK_SOURCE,
474 * MCAST_JOIN_GROUP, MCAST_LEAVE_GROUP MCAST_JOIN_SOURCE_GROUP,
475 * MCAST_LEAVE_SOURCE_GROUP, MCAST_BLOCK_SOURCE, MCAST_UNBLOCK_SOURCE,
476 * MCAST_MSFILTER, IP_MULTICAST_ALL are not supported, better not deal
477 * with mcast stuff
478 */
479 /* IP_IPSEC_POLICY, IP_XFRM_POLICY are nut supported, unrelated here */
480 return false;
481 }
482 if (level == SOL_IPV6) {
483 switch (optname) {
484 case IPV6_V6ONLY:
485
486 /* the following are control cmsg related */
487 case IPV6_RECVPKTINFO:
488 case IPV6_2292PKTINFO:
489 case IPV6_RECVHOPLIMIT:
490 case IPV6_2292HOPLIMIT:
491 case IPV6_RECVRTHDR:
492 case IPV6_2292RTHDR:
493 case IPV6_RECVHOPOPTS:
494 case IPV6_2292HOPOPTS:
495 case IPV6_RECVDSTOPTS:
496 case IPV6_2292DSTOPTS:
497 case IPV6_RECVTCLASS:
498 case IPV6_FLOWINFO:
499 case IPV6_RECVPATHMTU:
500 case IPV6_RECVORIGDSTADDR:
501 case IPV6_RECVFRAGSIZE:
502
503 /* the following ones need some love but are quite common */
504 case IPV6_TCLASS:
505 case IPV6_TRANSPARENT:
506 case IPV6_FREEBIND:
507 case IPV6_PKTINFO:
508 case IPV6_2292PKTOPTIONS:
509 case IPV6_UNICAST_HOPS:
510 case IPV6_MTU_DISCOVER:
511 case IPV6_MTU:
512 case IPV6_RECVERR:
513 case IPV6_FLOWINFO_SEND:
514 case IPV6_FLOWLABEL_MGR:
515 case IPV6_MINHOPCOUNT:
516 case IPV6_DONTFRAG:
517 case IPV6_AUTOFLOWLABEL:
518
519 /* the following one is a no-op for plain TCP */
520 case IPV6_RECVERR_RFC4884:
521 return true;
522 }
523
524 /* IPV6_HOPOPTS, IPV6_RTHDRDSTOPTS, IPV6_RTHDR, IPV6_DSTOPTS are
525 * not supported
526 */
527 /* IPV6_MULTICAST_HOPS, IPV6_MULTICAST_LOOP, IPV6_UNICAST_IF,
528 * IPV6_MULTICAST_IF, IPV6_ADDRFORM,
529 * IPV6_ADD_MEMBERSHIP, IPV6_DROP_MEMBERSHIP, IPV6_JOIN_ANYCAST,
530 * IPV6_LEAVE_ANYCAST, IPV6_MULTICAST_ALL, MCAST_JOIN_GROUP, MCAST_LEAVE_GROUP,
531 * MCAST_JOIN_SOURCE_GROUP, MCAST_LEAVE_SOURCE_GROUP,
532 * MCAST_BLOCK_SOURCE, MCAST_UNBLOCK_SOURCE, MCAST_MSFILTER
533 * are not supported better not deal with mcast
534 */
535 /* IPV6_ROUTER_ALERT, IPV6_ROUTER_ALERT_ISOLATE are not supported, since are evil */
536
537 /* IPV6_IPSEC_POLICY, IPV6_XFRM_POLICY are not supported */
538 /* IPV6_ADDR_PREFERENCES is not supported, we must be careful with subflows */
539 return false;
540 }
541 if (level == SOL_TCP) {
542 switch (optname) {
543 /* the following are no-op or should work just fine */
544 case TCP_THIN_DUPACK:
545 case TCP_DEFER_ACCEPT:
546
547 /* the following need some love */
548 case TCP_MAXSEG:
549 case TCP_NODELAY:
550 case TCP_THIN_LINEAR_TIMEOUTS:
551 case TCP_CONGESTION:
552 case TCP_CORK:
553 case TCP_KEEPIDLE:
554 case TCP_KEEPINTVL:
555 case TCP_KEEPCNT:
556 case TCP_SYNCNT:
557 case TCP_SAVE_SYN:
558 case TCP_LINGER2:
559 case TCP_WINDOW_CLAMP:
560 case TCP_QUICKACK:
561 case TCP_USER_TIMEOUT:
562 case TCP_TIMESTAMP:
563 case TCP_NOTSENT_LOWAT:
564 case TCP_TX_DELAY:
565 case TCP_INQ:
566 case TCP_FASTOPEN:
567 case TCP_FASTOPEN_CONNECT:
568 case TCP_FASTOPEN_KEY:
569 case TCP_FASTOPEN_NO_COOKIE:
570 return true;
571 }
572
573 /* TCP_MD5SIG, TCP_MD5SIG_EXT are not supported, MD5 is not compatible with MPTCP */
574
575 /* TCP_REPAIR, TCP_REPAIR_QUEUE, TCP_QUEUE_SEQ, TCP_REPAIR_OPTIONS,
576 * TCP_REPAIR_WINDOW are not supported, better avoid this mess
577 */
578 }
579 return false;
580 }
581
582 static int mptcp_setsockopt_sol_tcp_congestion(struct mptcp_sock *msk, sockptr_t optval,
583 unsigned int optlen)
584 {
585 struct mptcp_subflow_context *subflow;
586 struct sock *sk = (struct sock *)msk;
587 char name[TCP_CA_NAME_MAX];
588 bool cap_net_admin;
589 int ret;
590
591 if (optlen < 1)
592 return -EINVAL;
593
594 ret = strncpy_from_sockptr(name, optval,
595 min_t(long, TCP_CA_NAME_MAX - 1, optlen));
596 if (ret < 0)
597 return -EFAULT;
598
599 name[ret] = 0;
600
601 cap_net_admin = ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN);
602
603 ret = 0;
604 lock_sock(sk);
605 sockopt_seq_inc(msk);
606 mptcp_for_each_subflow(msk, subflow) {
607 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
608 int err;
609
610 lock_sock(ssk);
611 err = tcp_set_congestion_control(ssk, name, true, cap_net_admin);
612 if (err < 0 && ret == 0)
613 ret = err;
614 subflow->setsockopt_seq = msk->setsockopt_seq;
615 release_sock(ssk);
616 }
617
618 if (ret == 0)
619 strscpy(msk->ca_name, name, sizeof(msk->ca_name));
620
621 release_sock(sk);
622 return ret;
623 }
624
625 static int __mptcp_setsockopt_set_val(struct mptcp_sock *msk, int max,
626 int (*set_val)(struct sock *, int),
627 int *msk_val, int val)
628 {
629 struct mptcp_subflow_context *subflow;
630 int err = 0;
631
632 mptcp_for_each_subflow(msk, subflow) {
633 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
634 int ret;
635
636 lock_sock(ssk);
637 ret = set_val(ssk, val);
638 err = err ? : ret;
639 release_sock(ssk);
640 }
641
642 if (!err) {
643 *msk_val = val;
644 sockopt_seq_inc(msk);
645 }
646
647 return err;
648 }
649
650 static int __mptcp_setsockopt_sol_tcp_cork(struct mptcp_sock *msk, int val)
651 {
652 struct mptcp_subflow_context *subflow;
653 struct sock *sk = (struct sock *)msk;
654
655 sockopt_seq_inc(msk);
656 msk->cork = !!val;
657 mptcp_for_each_subflow(msk, subflow) {
658 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
659
660 lock_sock(ssk);
661 __tcp_sock_set_cork(ssk, !!val);
662 release_sock(ssk);
663 }
664 if (!val)
665 mptcp_check_and_set_pending(sk);
666
667 return 0;
668 }
669
670 static int __mptcp_setsockopt_sol_tcp_nodelay(struct mptcp_sock *msk, int val)
671 {
672 struct mptcp_subflow_context *subflow;
673 struct sock *sk = (struct sock *)msk;
674
675 sockopt_seq_inc(msk);
676 msk->nodelay = !!val;
677 mptcp_for_each_subflow(msk, subflow) {
678 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
679
680 lock_sock(ssk);
681 __tcp_sock_set_nodelay(ssk, !!val);
682 release_sock(ssk);
683 }
684 if (val)
685 mptcp_check_and_set_pending(sk);
686 return 0;
687 }
688
689 static int mptcp_setsockopt_sol_ip_set(struct mptcp_sock *msk, int optname,
690 sockptr_t optval, unsigned int optlen)
691 {
692 struct sock *sk = (struct sock *)msk;
693 struct sock *ssk;
694 int err;
695
696 err = ip_setsockopt(sk, SOL_IP, optname, optval, optlen);
697 if (err != 0)
698 return err;
699
700 lock_sock(sk);
701
702 ssk = __mptcp_nmpc_sk(msk);
703 if (IS_ERR(ssk)) {
704 release_sock(sk);
705 return PTR_ERR(ssk);
706 }
707
708 switch (optname) {
709 case IP_FREEBIND:
710 inet_assign_bit(FREEBIND, ssk, inet_test_bit(FREEBIND, sk));
711 break;
712 case IP_TRANSPARENT:
713 inet_assign_bit(TRANSPARENT, ssk,
714 inet_test_bit(TRANSPARENT, sk));
715 break;
716 case IP_BIND_ADDRESS_NO_PORT:
717 inet_assign_bit(BIND_ADDRESS_NO_PORT, ssk,
718 inet_test_bit(BIND_ADDRESS_NO_PORT, sk));
719 break;
720 case IP_LOCAL_PORT_RANGE:
721 WRITE_ONCE(inet_sk(ssk)->local_port_range,
722 READ_ONCE(inet_sk(sk)->local_port_range));
723 break;
724 default:
725 release_sock(sk);
726 WARN_ON_ONCE(1);
727 return -EOPNOTSUPP;
728 }
729
730 sockopt_seq_inc(msk);
731 release_sock(sk);
732 return 0;
733 }
734
735 static int mptcp_setsockopt_v4_set_tos(struct mptcp_sock *msk, int optname,
736 sockptr_t optval, unsigned int optlen)
737 {
738 struct mptcp_subflow_context *subflow;
739 struct sock *sk = (struct sock *)msk;
740 int err, val;
741
742 err = ip_setsockopt(sk, SOL_IP, optname, optval, optlen);
743
744 if (err != 0)
745 return err;
746
747 lock_sock(sk);
748 sockopt_seq_inc(msk);
749 val = READ_ONCE(inet_sk(sk)->tos);
750 mptcp_for_each_subflow(msk, subflow) {
751 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
752 bool slow;
753
754 slow = lock_sock_fast(ssk);
755 __ip_sock_set_tos(ssk, val);
756 unlock_sock_fast(ssk, slow);
757 }
758 release_sock(sk);
759
760 return 0;
761 }
762
763 static int mptcp_setsockopt_v4(struct mptcp_sock *msk, int optname,
764 sockptr_t optval, unsigned int optlen)
765 {
766 switch (optname) {
767 case IP_FREEBIND:
768 case IP_TRANSPARENT:
769 case IP_BIND_ADDRESS_NO_PORT:
770 case IP_LOCAL_PORT_RANGE:
771 return mptcp_setsockopt_sol_ip_set(msk, optname, optval, optlen);
772 case IP_TOS:
773 return mptcp_setsockopt_v4_set_tos(msk, optname, optval, optlen);
774 }
775
776 return -EOPNOTSUPP;
777 }
778
779 static int mptcp_setsockopt_first_sf_only(struct mptcp_sock *msk, int level, int optname,
780 sockptr_t optval, unsigned int optlen)
781 {
782 struct sock *sk = (struct sock *)msk;
783 struct sock *ssk;
784 int ret;
785
786 /* Limit to first subflow, before the connection establishment */
787 lock_sock(sk);
788 ssk = __mptcp_nmpc_sk(msk);
789 if (IS_ERR(ssk)) {
790 ret = PTR_ERR(ssk);
791 goto unlock;
792 }
793
794 ret = tcp_setsockopt(ssk, level, optname, optval, optlen);
795
796 unlock:
797 release_sock(sk);
798 return ret;
799 }
800
801 static int mptcp_setsockopt_sol_tcp(struct mptcp_sock *msk, int optname,
802 sockptr_t optval, unsigned int optlen)
803 {
804 struct sock *sk = (void *)msk;
805 int ret, val;
806
807 switch (optname) {
808 case TCP_ULP:
809 return -EOPNOTSUPP;
810 case TCP_CONGESTION:
811 return mptcp_setsockopt_sol_tcp_congestion(msk, optval, optlen);
812 case TCP_DEFER_ACCEPT:
813 /* See tcp.c: TCP_DEFER_ACCEPT does not fail */
814 mptcp_setsockopt_first_sf_only(msk, SOL_TCP, optname, optval, optlen);
815 return 0;
816 case TCP_FASTOPEN:
817 case TCP_FASTOPEN_CONNECT:
818 case TCP_FASTOPEN_KEY:
819 case TCP_FASTOPEN_NO_COOKIE:
820 return mptcp_setsockopt_first_sf_only(msk, SOL_TCP, optname,
821 optval, optlen);
822 }
823
824 ret = mptcp_get_int_option(msk, optval, optlen, &val);
825 if (ret)
826 return ret;
827
828 lock_sock(sk);
829 switch (optname) {
830 case TCP_INQ:
831 if (val < 0 || val > 1)
832 ret = -EINVAL;
833 else
834 msk->recvmsg_inq = !!val;
835 break;
836 case TCP_NOTSENT_LOWAT:
837 WRITE_ONCE(msk->notsent_lowat, val);
838 mptcp_write_space(sk);
839 break;
840 case TCP_CORK:
841 ret = __mptcp_setsockopt_sol_tcp_cork(msk, val);
842 break;
843 case TCP_NODELAY:
844 ret = __mptcp_setsockopt_sol_tcp_nodelay(msk, val);
845 break;
846 case TCP_KEEPIDLE:
847 ret = __mptcp_setsockopt_set_val(msk, MAX_TCP_KEEPIDLE,
848 &tcp_sock_set_keepidle_locked,
849 &msk->keepalive_idle, val);
850 break;
851 case TCP_KEEPINTVL:
852 ret = __mptcp_setsockopt_set_val(msk, MAX_TCP_KEEPINTVL,
853 &tcp_sock_set_keepintvl,
854 &msk->keepalive_intvl, val);
855 break;
856 case TCP_KEEPCNT:
857 ret = __mptcp_setsockopt_set_val(msk, MAX_TCP_KEEPCNT,
858 &tcp_sock_set_keepcnt,
859 &msk->keepalive_cnt,
860 val);
861 break;
862 default:
863 ret = -ENOPROTOOPT;
864 }
865
866 release_sock(sk);
867 return ret;
868 }
869
870 int mptcp_setsockopt(struct sock *sk, int level, int optname,
871 sockptr_t optval, unsigned int optlen)
872 {
873 struct mptcp_sock *msk = mptcp_sk(sk);
874 struct sock *ssk;
875
876 pr_debug("msk=%p\n", msk);
877
878 if (level == SOL_SOCKET)
879 return mptcp_setsockopt_sol_socket(msk, optname, optval, optlen);
880
881 if (!mptcp_supported_sockopt(level, optname))
882 return -ENOPROTOOPT;
883
884 /* @@ the meaning of setsockopt() when the socket is connected and
885 * there are multiple subflows is not yet defined. It is up to the
886 * MPTCP-level socket to configure the subflows until the subflow
887 * is in TCP fallback, when TCP socket options are passed through
888 * to the one remaining subflow.
889 */
890 lock_sock(sk);
891 ssk = __mptcp_tcp_fallback(msk);
892 release_sock(sk);
893 if (ssk)
894 return tcp_setsockopt(ssk, level, optname, optval, optlen);
895
896 if (level == SOL_IP)
897 return mptcp_setsockopt_v4(msk, optname, optval, optlen);
898
899 if (level == SOL_IPV6)
900 return mptcp_setsockopt_v6(msk, optname, optval, optlen);
901
902 if (level == SOL_TCP)
903 return mptcp_setsockopt_sol_tcp(msk, optname, optval, optlen);
904
905 return -EOPNOTSUPP;
906 }
907
908 static int mptcp_getsockopt_first_sf_only(struct mptcp_sock *msk, int level, int optname,
909 char __user *optval, int __user *optlen)
910 {
911 struct sock *sk = (struct sock *)msk;
912 struct sock *ssk;
913 int ret;
914
915 lock_sock(sk);
916 ssk = msk->first;
917 if (ssk) {
918 ret = tcp_getsockopt(ssk, level, optname, optval, optlen);
919 goto out;
920 }
921
922 ssk = __mptcp_nmpc_sk(msk);
923 if (IS_ERR(ssk)) {
924 ret = PTR_ERR(ssk);
925 goto out;
926 }
927
928 ret = tcp_getsockopt(ssk, level, optname, optval, optlen);
929
930 out:
931 release_sock(sk);
932 return ret;
933 }
934
935 void mptcp_diag_fill_info(struct mptcp_sock *msk, struct mptcp_info *info)
936 {
937 struct sock *sk = (struct sock *)msk;
938 u32 flags = 0;
939 bool slow;
940 u32 now;
941
942 memset(info, 0, sizeof(*info));
943
944 info->mptcpi_subflows = READ_ONCE(msk->pm.subflows);
945 info->mptcpi_add_addr_signal = READ_ONCE(msk->pm.add_addr_signaled);
946 info->mptcpi_add_addr_accepted = READ_ONCE(msk->pm.add_addr_accepted);
947 info->mptcpi_local_addr_used = READ_ONCE(msk->pm.local_addr_used);
948
949 if (inet_sk_state_load(sk) == TCP_LISTEN)
950 return;
951
952 /* The following limits only make sense for the in-kernel PM */
953 if (mptcp_pm_is_kernel(msk)) {
954 info->mptcpi_subflows_max =
955 mptcp_pm_get_subflows_max(msk);
956 info->mptcpi_add_addr_signal_max =
957 mptcp_pm_get_add_addr_signal_max(msk);
958 info->mptcpi_add_addr_accepted_max =
959 mptcp_pm_get_add_addr_accept_max(msk);
960 info->mptcpi_local_addr_max =
961 mptcp_pm_get_local_addr_max(msk);
962 }
963
964 if (__mptcp_check_fallback(msk))
965 flags |= MPTCP_INFO_FLAG_FALLBACK;
966 if (READ_ONCE(msk->can_ack))
967 flags |= MPTCP_INFO_FLAG_REMOTE_KEY_RECEIVED;
968 info->mptcpi_flags = flags;
969
970 slow = lock_sock_fast(sk);
971 info->mptcpi_csum_enabled = READ_ONCE(msk->csum_enabled);
972 info->mptcpi_token = msk->token;
973 info->mptcpi_write_seq = msk->write_seq;
974 info->mptcpi_retransmits = inet_csk(sk)->icsk_retransmits;
975 info->mptcpi_bytes_sent = msk->bytes_sent;
976 info->mptcpi_bytes_received = msk->bytes_received;
977 info->mptcpi_bytes_retrans = msk->bytes_retrans;
978 info->mptcpi_subflows_total = info->mptcpi_subflows +
979 __mptcp_has_initial_subflow(msk);
980 now = tcp_jiffies32;
981 info->mptcpi_last_data_sent = jiffies_to_msecs(now - msk->last_data_sent);
982 info->mptcpi_last_data_recv = jiffies_to_msecs(now - msk->last_data_recv);
983 unlock_sock_fast(sk, slow);
984
985 mptcp_data_lock(sk);
986 info->mptcpi_last_ack_recv = jiffies_to_msecs(now - msk->last_ack_recv);
987 info->mptcpi_snd_una = msk->snd_una;
988 info->mptcpi_rcv_nxt = msk->ack_seq;
989 info->mptcpi_bytes_acked = msk->bytes_acked;
990 mptcp_data_unlock(sk);
991 }
992 EXPORT_SYMBOL_GPL(mptcp_diag_fill_info);
993
994 static int mptcp_getsockopt_info(struct mptcp_sock *msk, char __user *optval, int __user *optlen)
995 {
996 struct mptcp_info m_info;
997 int len;
998
999 if (get_user(len, optlen))
1000 return -EFAULT;
1001
1002 /* When used only to check if a fallback to TCP happened. */
1003 if (len == 0)
1004 return 0;
1005
1006 len = min_t(unsigned int, len, sizeof(struct mptcp_info));
1007
1008 mptcp_diag_fill_info(msk, &m_info);
1009
1010 if (put_user(len, optlen))
1011 return -EFAULT;
1012
1013 if (copy_to_user(optval, &m_info, len))
1014 return -EFAULT;
1015
1016 return 0;
1017 }
1018
1019 static int mptcp_put_subflow_data(struct mptcp_subflow_data *sfd,
1020 char __user *optval,
1021 u32 copied,
1022 int __user *optlen)
1023 {
1024 u32 copylen = min_t(u32, sfd->size_subflow_data, sizeof(*sfd));
1025
1026 if (copied)
1027 copied += sfd->size_subflow_data;
1028 else
1029 copied = copylen;
1030
1031 if (put_user(copied, optlen))
1032 return -EFAULT;
1033
1034 if (copy_to_user(optval, sfd, copylen))
1035 return -EFAULT;
1036
1037 return 0;
1038 }
1039
1040 static int mptcp_get_subflow_data(struct mptcp_subflow_data *sfd,
1041 char __user *optval,
1042 int __user *optlen)
1043 {
1044 int len, copylen;
1045
1046 if (get_user(len, optlen))
1047 return -EFAULT;
1048
1049 /* if mptcp_subflow_data size is changed, need to adjust
1050 * this function to deal with programs using old version.
1051 */
1052 BUILD_BUG_ON(sizeof(*sfd) != MIN_INFO_OPTLEN_SIZE);
1053
1054 if (len < MIN_INFO_OPTLEN_SIZE)
1055 return -EINVAL;
1056
1057 memset(sfd, 0, sizeof(*sfd));
1058
1059 copylen = min_t(unsigned int, len, sizeof(*sfd));
1060 if (copy_from_user(sfd, optval, copylen))
1061 return -EFAULT;
1062
1063 /* size_subflow_data is u32, but len is signed */
1064 if (sfd->size_subflow_data > INT_MAX ||
1065 sfd->size_user > INT_MAX)
1066 return -EINVAL;
1067
1068 if (sfd->size_subflow_data < MIN_INFO_OPTLEN_SIZE ||
1069 sfd->size_subflow_data > len)
1070 return -EINVAL;
1071
1072 if (sfd->num_subflows || sfd->size_kernel)
1073 return -EINVAL;
1074
1075 return len - sfd->size_subflow_data;
1076 }
1077
1078 static int mptcp_getsockopt_tcpinfo(struct mptcp_sock *msk, char __user *optval,
1079 int __user *optlen)
1080 {
1081 struct mptcp_subflow_context *subflow;
1082 struct sock *sk = (struct sock *)msk;
1083 unsigned int sfcount = 0, copied = 0;
1084 struct mptcp_subflow_data sfd;
1085 char __user *infoptr;
1086 int len;
1087
1088 len = mptcp_get_subflow_data(&sfd, optval, optlen);
1089 if (len < 0)
1090 return len;
1091
1092 sfd.size_kernel = sizeof(struct tcp_info);
1093 sfd.size_user = min_t(unsigned int, sfd.size_user,
1094 sizeof(struct tcp_info));
1095
1096 infoptr = optval + sfd.size_subflow_data;
1097
1098 lock_sock(sk);
1099
1100 mptcp_for_each_subflow(msk, subflow) {
1101 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
1102
1103 ++sfcount;
1104
1105 if (len && len >= sfd.size_user) {
1106 struct tcp_info info;
1107
1108 tcp_get_info(ssk, &info);
1109
1110 if (copy_to_user(infoptr, &info, sfd.size_user)) {
1111 release_sock(sk);
1112 return -EFAULT;
1113 }
1114
1115 infoptr += sfd.size_user;
1116 copied += sfd.size_user;
1117 len -= sfd.size_user;
1118 }
1119 }
1120
1121 release_sock(sk);
1122
1123 sfd.num_subflows = sfcount;
1124
1125 if (mptcp_put_subflow_data(&sfd, optval, copied, optlen))
1126 return -EFAULT;
1127
1128 return 0;
1129 }
1130
1131 static void mptcp_get_sub_addrs(const struct sock *sk, struct mptcp_subflow_addrs *a)
1132 {
1133 const struct inet_sock *inet = inet_sk(sk);
1134
1135 memset(a, 0, sizeof(*a));
1136
1137 if (sk->sk_family == AF_INET) {
1138 a->sin_local.sin_family = AF_INET;
1139 a->sin_local.sin_port = inet->inet_sport;
1140 a->sin_local.sin_addr.s_addr = inet->inet_rcv_saddr;
1141
1142 if (!a->sin_local.sin_addr.s_addr)
1143 a->sin_local.sin_addr.s_addr = inet->inet_saddr;
1144
1145 a->sin_remote.sin_family = AF_INET;
1146 a->sin_remote.sin_port = inet->inet_dport;
1147 a->sin_remote.sin_addr.s_addr = inet->inet_daddr;
1148 #if IS_ENABLED(CONFIG_IPV6)
1149 } else if (sk->sk_family == AF_INET6) {
1150 const struct ipv6_pinfo *np = inet6_sk(sk);
1151
1152 if (WARN_ON_ONCE(!np))
1153 return;
1154
1155 a->sin6_local.sin6_family = AF_INET6;
1156 a->sin6_local.sin6_port = inet->inet_sport;
1157
1158 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr))
1159 a->sin6_local.sin6_addr = np->saddr;
1160 else
1161 a->sin6_local.sin6_addr = sk->sk_v6_rcv_saddr;
1162
1163 a->sin6_remote.sin6_family = AF_INET6;
1164 a->sin6_remote.sin6_port = inet->inet_dport;
1165 a->sin6_remote.sin6_addr = sk->sk_v6_daddr;
1166 #endif
1167 }
1168 }
1169
1170 static int mptcp_getsockopt_subflow_addrs(struct mptcp_sock *msk, char __user *optval,
1171 int __user *optlen)
1172 {
1173 struct mptcp_subflow_context *subflow;
1174 struct sock *sk = (struct sock *)msk;
1175 unsigned int sfcount = 0, copied = 0;
1176 struct mptcp_subflow_data sfd;
1177 char __user *addrptr;
1178 int len;
1179
1180 len = mptcp_get_subflow_data(&sfd, optval, optlen);
1181 if (len < 0)
1182 return len;
1183
1184 sfd.size_kernel = sizeof(struct mptcp_subflow_addrs);
1185 sfd.size_user = min_t(unsigned int, sfd.size_user,
1186 sizeof(struct mptcp_subflow_addrs));
1187
1188 addrptr = optval + sfd.size_subflow_data;
1189
1190 lock_sock(sk);
1191
1192 mptcp_for_each_subflow(msk, subflow) {
1193 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
1194
1195 ++sfcount;
1196
1197 if (len && len >= sfd.size_user) {
1198 struct mptcp_subflow_addrs a;
1199
1200 mptcp_get_sub_addrs(ssk, &a);
1201
1202 if (copy_to_user(addrptr, &a, sfd.size_user)) {
1203 release_sock(sk);
1204 return -EFAULT;
1205 }
1206
1207 addrptr += sfd.size_user;
1208 copied += sfd.size_user;
1209 len -= sfd.size_user;
1210 }
1211 }
1212
1213 release_sock(sk);
1214
1215 sfd.num_subflows = sfcount;
1216
1217 if (mptcp_put_subflow_data(&sfd, optval, copied, optlen))
1218 return -EFAULT;
1219
1220 return 0;
1221 }
1222
1223 static int mptcp_get_full_info(struct mptcp_full_info *mfi,
1224 char __user *optval,
1225 int __user *optlen)
1226 {
1227 int len;
1228
1229 BUILD_BUG_ON(offsetof(struct mptcp_full_info, mptcp_info) !=
1230 MIN_FULL_INFO_OPTLEN_SIZE);
1231
1232 if (get_user(len, optlen))
1233 return -EFAULT;
1234
1235 if (len < MIN_FULL_INFO_OPTLEN_SIZE)
1236 return -EINVAL;
1237
1238 memset(mfi, 0, sizeof(*mfi));
1239 if (copy_from_user(mfi, optval, MIN_FULL_INFO_OPTLEN_SIZE))
1240 return -EFAULT;
1241
1242 if (mfi->size_tcpinfo_kernel ||
1243 mfi->size_sfinfo_kernel ||
1244 mfi->num_subflows)
1245 return -EINVAL;
1246
1247 if (mfi->size_sfinfo_user > INT_MAX ||
1248 mfi->size_tcpinfo_user > INT_MAX)
1249 return -EINVAL;
1250
1251 return len - MIN_FULL_INFO_OPTLEN_SIZE;
1252 }
1253
1254 static int mptcp_put_full_info(struct mptcp_full_info *mfi,
1255 char __user *optval,
1256 u32 copylen,
1257 int __user *optlen)
1258 {
1259 copylen += MIN_FULL_INFO_OPTLEN_SIZE;
1260 if (put_user(copylen, optlen))
1261 return -EFAULT;
1262
1263 if (copy_to_user(optval, mfi, copylen))
1264 return -EFAULT;
1265 return 0;
1266 }
1267
1268 static int mptcp_getsockopt_full_info(struct mptcp_sock *msk, char __user *optval,
1269 int __user *optlen)
1270 {
1271 unsigned int sfcount = 0, copylen = 0;
1272 struct mptcp_subflow_context *subflow;
1273 struct sock *sk = (struct sock *)msk;
1274 void __user *tcpinfoptr, *sfinfoptr;
1275 struct mptcp_full_info mfi;
1276 int len;
1277
1278 len = mptcp_get_full_info(&mfi, optval, optlen);
1279 if (len < 0)
1280 return len;
1281
1282 /* don't bother filling the mptcp info if there is not enough
1283 * user-space-provided storage
1284 */
1285 if (len > 0) {
1286 mptcp_diag_fill_info(msk, &mfi.mptcp_info);
1287 copylen += min_t(unsigned int, len, sizeof(struct mptcp_info));
1288 }
1289
1290 mfi.size_tcpinfo_kernel = sizeof(struct tcp_info);
1291 mfi.size_tcpinfo_user = min_t(unsigned int, mfi.size_tcpinfo_user,
1292 sizeof(struct tcp_info));
1293 sfinfoptr = u64_to_user_ptr(mfi.subflow_info);
1294 mfi.size_sfinfo_kernel = sizeof(struct mptcp_subflow_info);
1295 mfi.size_sfinfo_user = min_t(unsigned int, mfi.size_sfinfo_user,
1296 sizeof(struct mptcp_subflow_info));
1297 tcpinfoptr = u64_to_user_ptr(mfi.tcp_info);
1298
1299 lock_sock(sk);
1300 mptcp_for_each_subflow(msk, subflow) {
1301 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
1302 struct mptcp_subflow_info sfinfo;
1303 struct tcp_info tcp_info;
1304
1305 if (sfcount++ >= mfi.size_arrays_user)
1306 continue;
1307
1308 /* fetch addr/tcp_info only if the user space buffers
1309 * are wide enough
1310 */
1311 memset(&sfinfo, 0, sizeof(sfinfo));
1312 sfinfo.id = subflow->subflow_id;
1313 if (mfi.size_sfinfo_user >
1314 offsetof(struct mptcp_subflow_info, addrs))
1315 mptcp_get_sub_addrs(ssk, &sfinfo.addrs);
1316 if (copy_to_user(sfinfoptr, &sfinfo, mfi.size_sfinfo_user))
1317 goto fail_release;
1318
1319 if (mfi.size_tcpinfo_user) {
1320 tcp_get_info(ssk, &tcp_info);
1321 if (copy_to_user(tcpinfoptr, &tcp_info,
1322 mfi.size_tcpinfo_user))
1323 goto fail_release;
1324 }
1325
1326 tcpinfoptr += mfi.size_tcpinfo_user;
1327 sfinfoptr += mfi.size_sfinfo_user;
1328 }
1329 release_sock(sk);
1330
1331 mfi.num_subflows = sfcount;
1332 if (mptcp_put_full_info(&mfi, optval, copylen, optlen))
1333 return -EFAULT;
1334
1335 return 0;
1336
1337 fail_release:
1338 release_sock(sk);
1339 return -EFAULT;
1340 }
1341
1342 static int mptcp_put_int_option(struct mptcp_sock *msk, char __user *optval,
1343 int __user *optlen, int val)
1344 {
1345 int len;
1346
1347 if (get_user(len, optlen))
1348 return -EFAULT;
1349 if (len < 0)
1350 return -EINVAL;
1351
1352 if (len < sizeof(int) && len > 0 && val >= 0 && val <= 255) {
1353 unsigned char ucval = (unsigned char)val;
1354
1355 len = 1;
1356 if (put_user(len, optlen))
1357 return -EFAULT;
1358 if (copy_to_user(optval, &ucval, 1))
1359 return -EFAULT;
1360 } else {
1361 len = min_t(unsigned int, len, sizeof(int));
1362 if (put_user(len, optlen))
1363 return -EFAULT;
1364 if (copy_to_user(optval, &val, len))
1365 return -EFAULT;
1366 }
1367
1368 return 0;
1369 }
1370
1371 static int mptcp_getsockopt_sol_tcp(struct mptcp_sock *msk, int optname,
1372 char __user *optval, int __user *optlen)
1373 {
1374 struct sock *sk = (void *)msk;
1375
1376 switch (optname) {
1377 case TCP_ULP:
1378 case TCP_CONGESTION:
1379 case TCP_INFO:
1380 case TCP_CC_INFO:
1381 case TCP_DEFER_ACCEPT:
1382 case TCP_FASTOPEN:
1383 case TCP_FASTOPEN_CONNECT:
1384 case TCP_FASTOPEN_KEY:
1385 case TCP_FASTOPEN_NO_COOKIE:
1386 return mptcp_getsockopt_first_sf_only(msk, SOL_TCP, optname,
1387 optval, optlen);
1388 case TCP_INQ:
1389 return mptcp_put_int_option(msk, optval, optlen, msk->recvmsg_inq);
1390 case TCP_CORK:
1391 return mptcp_put_int_option(msk, optval, optlen, msk->cork);
1392 case TCP_NODELAY:
1393 return mptcp_put_int_option(msk, optval, optlen, msk->nodelay);
1394 case TCP_KEEPIDLE:
1395 return mptcp_put_int_option(msk, optval, optlen,
1396 msk->keepalive_idle ? :
1397 READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_keepalive_time) / HZ);
1398 case TCP_KEEPINTVL:
1399 return mptcp_put_int_option(msk, optval, optlen,
1400 msk->keepalive_intvl ? :
1401 READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_keepalive_intvl) / HZ);
1402 case TCP_KEEPCNT:
1403 return mptcp_put_int_option(msk, optval, optlen,
1404 msk->keepalive_cnt ? :
1405 READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_keepalive_probes));
1406 case TCP_NOTSENT_LOWAT:
1407 return mptcp_put_int_option(msk, optval, optlen, msk->notsent_lowat);
1408 case TCP_IS_MPTCP:
1409 return mptcp_put_int_option(msk, optval, optlen, 1);
1410 }
1411 return -EOPNOTSUPP;
1412 }
1413
1414 static int mptcp_getsockopt_v4(struct mptcp_sock *msk, int optname,
1415 char __user *optval, int __user *optlen)
1416 {
1417 struct sock *sk = (void *)msk;
1418
1419 switch (optname) {
1420 case IP_TOS:
1421 return mptcp_put_int_option(msk, optval, optlen, READ_ONCE(inet_sk(sk)->tos));
1422 case IP_BIND_ADDRESS_NO_PORT:
1423 return mptcp_put_int_option(msk, optval, optlen,
1424 inet_test_bit(BIND_ADDRESS_NO_PORT, sk));
1425 case IP_LOCAL_PORT_RANGE:
1426 return mptcp_put_int_option(msk, optval, optlen,
1427 READ_ONCE(inet_sk(sk)->local_port_range));
1428 }
1429
1430 return -EOPNOTSUPP;
1431 }
1432
1433 static int mptcp_getsockopt_sol_mptcp(struct mptcp_sock *msk, int optname,
1434 char __user *optval, int __user *optlen)
1435 {
1436 switch (optname) {
1437 case MPTCP_INFO:
1438 return mptcp_getsockopt_info(msk, optval, optlen);
1439 case MPTCP_FULL_INFO:
1440 return mptcp_getsockopt_full_info(msk, optval, optlen);
1441 case MPTCP_TCPINFO:
1442 return mptcp_getsockopt_tcpinfo(msk, optval, optlen);
1443 case MPTCP_SUBFLOW_ADDRS:
1444 return mptcp_getsockopt_subflow_addrs(msk, optval, optlen);
1445 }
1446
1447 return -EOPNOTSUPP;
1448 }
1449
1450 int mptcp_getsockopt(struct sock *sk, int level, int optname,
1451 char __user *optval, int __user *option)
1452 {
1453 struct mptcp_sock *msk = mptcp_sk(sk);
1454 struct sock *ssk;
1455
1456 pr_debug("msk=%p\n", msk);
1457
1458 /* @@ the meaning of setsockopt() when the socket is connected and
1459 * there are multiple subflows is not yet defined. It is up to the
1460 * MPTCP-level socket to configure the subflows until the subflow
1461 * is in TCP fallback, when socket options are passed through
1462 * to the one remaining subflow.
1463 */
1464 lock_sock(sk);
1465 ssk = __mptcp_tcp_fallback(msk);
1466 release_sock(sk);
1467 if (ssk)
1468 return tcp_getsockopt(ssk, level, optname, optval, option);
1469
1470 if (level == SOL_IP)
1471 return mptcp_getsockopt_v4(msk, optname, optval, option);
1472 if (level == SOL_TCP)
1473 return mptcp_getsockopt_sol_tcp(msk, optname, optval, option);
1474 if (level == SOL_MPTCP)
1475 return mptcp_getsockopt_sol_mptcp(msk, optname, optval, option);
1476 return -EOPNOTSUPP;
1477 }
1478
1479 static void sync_socket_options(struct mptcp_sock *msk, struct sock *ssk)
1480 {
1481 static const unsigned int tx_rx_locks = SOCK_RCVBUF_LOCK | SOCK_SNDBUF_LOCK;
1482 struct sock *sk = (struct sock *)msk;
1483
1484 if (ssk->sk_prot->keepalive) {
1485 if (sock_flag(sk, SOCK_KEEPOPEN))
1486 ssk->sk_prot->keepalive(ssk, 1);
1487 else
1488 ssk->sk_prot->keepalive(ssk, 0);
1489 }
1490
1491 ssk->sk_priority = sk->sk_priority;
1492 ssk->sk_bound_dev_if = sk->sk_bound_dev_if;
1493 ssk->sk_incoming_cpu = sk->sk_incoming_cpu;
1494 ssk->sk_ipv6only = sk->sk_ipv6only;
1495 __ip_sock_set_tos(ssk, inet_sk(sk)->tos);
1496
1497 if (sk->sk_userlocks & tx_rx_locks) {
1498 ssk->sk_userlocks |= sk->sk_userlocks & tx_rx_locks;
1499 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) {
1500 WRITE_ONCE(ssk->sk_sndbuf, sk->sk_sndbuf);
1501 mptcp_subflow_ctx(ssk)->cached_sndbuf = sk->sk_sndbuf;
1502 }
1503 if (sk->sk_userlocks & SOCK_RCVBUF_LOCK)
1504 WRITE_ONCE(ssk->sk_rcvbuf, sk->sk_rcvbuf);
1505 }
1506
1507 if (sock_flag(sk, SOCK_LINGER)) {
1508 ssk->sk_lingertime = sk->sk_lingertime;
1509 sock_set_flag(ssk, SOCK_LINGER);
1510 } else {
1511 sock_reset_flag(ssk, SOCK_LINGER);
1512 }
1513
1514 if (sk->sk_mark != ssk->sk_mark) {
1515 ssk->sk_mark = sk->sk_mark;
1516 sk_dst_reset(ssk);
1517 }
1518
1519 sock_valbool_flag(ssk, SOCK_DBG, sock_flag(sk, SOCK_DBG));
1520
1521 if (inet_csk(sk)->icsk_ca_ops != inet_csk(ssk)->icsk_ca_ops)
1522 tcp_set_congestion_control(ssk, msk->ca_name, false, true);
1523 __tcp_sock_set_cork(ssk, !!msk->cork);
1524 __tcp_sock_set_nodelay(ssk, !!msk->nodelay);
1525 tcp_sock_set_keepidle_locked(ssk, msk->keepalive_idle);
1526 tcp_sock_set_keepintvl(ssk, msk->keepalive_intvl);
1527 tcp_sock_set_keepcnt(ssk, msk->keepalive_cnt);
1528
1529 inet_assign_bit(TRANSPARENT, ssk, inet_test_bit(TRANSPARENT, sk));
1530 inet_assign_bit(FREEBIND, ssk, inet_test_bit(FREEBIND, sk));
1531 inet_assign_bit(BIND_ADDRESS_NO_PORT, ssk, inet_test_bit(BIND_ADDRESS_NO_PORT, sk));
1532 WRITE_ONCE(inet_sk(ssk)->local_port_range, READ_ONCE(inet_sk(sk)->local_port_range));
1533 }
1534
1535 void mptcp_sockopt_sync_locked(struct mptcp_sock *msk, struct sock *ssk)
1536 {
1537 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
1538
1539 msk_owned_by_me(msk);
1540
1541 ssk->sk_rcvlowat = 0;
1542
1543 /* subflows must ignore any latency-related settings: will not affect
1544 * the user-space - only the msk is relevant - but will foul the
1545 * mptcp scheduler
1546 */
1547 tcp_sk(ssk)->notsent_lowat = UINT_MAX;
1548
1549 if (READ_ONCE(subflow->setsockopt_seq) != msk->setsockopt_seq) {
1550 sync_socket_options(msk, ssk);
1551
1552 subflow->setsockopt_seq = msk->setsockopt_seq;
1553 }
1554 }
1555
1556 /* unfortunately this is different enough from the tcp version so
1557 * that we can't factor it out
1558 */
1559 int mptcp_set_rcvlowat(struct sock *sk, int val)
1560 {
1561 struct mptcp_subflow_context *subflow;
1562 int space, cap;
1563
1564 /* bpf can land here with a wrong sk type */
1565 if (sk->sk_protocol == IPPROTO_TCP)
1566 return -EINVAL;
1567
1568 if (sk->sk_userlocks & SOCK_RCVBUF_LOCK)
1569 cap = sk->sk_rcvbuf >> 1;
1570 else
1571 cap = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_rmem[2]) >> 1;
1572 val = min(val, cap);
1573 WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1574
1575 /* Check if we need to signal EPOLLIN right now */
1576 if (mptcp_epollin_ready(sk))
1577 sk->sk_data_ready(sk);
1578
1579 if (sk->sk_userlocks & SOCK_RCVBUF_LOCK)
1580 return 0;
1581
1582 space = mptcp_space_from_win(sk, val);
1583 if (space <= sk->sk_rcvbuf)
1584 return 0;
1585
1586 /* propagate the rcvbuf changes to all the subflows */
1587 WRITE_ONCE(sk->sk_rcvbuf, space);
1588 mptcp_for_each_subflow(mptcp_sk(sk), subflow) {
1589 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
1590 bool slow;
1591
1592 slow = lock_sock_fast(ssk);
1593 WRITE_ONCE(ssk->sk_rcvbuf, space);
1594 WRITE_ONCE(tcp_sk(ssk)->window_clamp, val);
1595 unlock_sock_fast(ssk, slow);
1596 }
1597 return 0;
1598 }
1599
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