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
__mptcp_tcp_fallback(struct mptcp_sock * msk)19 static struct sock *__mptcp_tcp_fallback(struct mptcp_sock *msk)
20 {
21 sock_owned_by_me((const struct sock *)msk);
22
23 if (likely(!__mptcp_check_fallback(msk)))
24 return NULL;
25
26 return msk->first;
27 }
28
sockopt_seq_reset(const struct sock * sk)29 static u32 sockopt_seq_reset(const struct sock *sk)
30 {
31 sock_owned_by_me(sk);
32
33 /* Highbits contain state. Allows to distinguish sockopt_seq
34 * of listener and established:
35 * s0 = new_listener()
36 * sockopt(s0) - seq is 1
37 * s1 = accept(s0) - s1 inherits seq 1 if listener sk (s0)
38 * sockopt(s0) - seq increments to 2 on s0
39 * sockopt(s1) // seq increments to 2 on s1 (different option)
40 * new ssk completes join, inherits options from s0 // seq 2
41 * Needs sync from mptcp join logic, but ssk->seq == msk->seq
42 *
43 * Set High order bits to sk_state so ssk->seq == msk->seq test
44 * will fail.
45 */
46
47 return (u32)sk->sk_state << 24u;
48 }
49
sockopt_seq_inc(struct mptcp_sock * msk)50 static void sockopt_seq_inc(struct mptcp_sock *msk)
51 {
52 u32 seq = (msk->setsockopt_seq + 1) & 0x00ffffff;
53
54 msk->setsockopt_seq = sockopt_seq_reset((struct sock *)msk) + seq;
55 }
56
mptcp_get_int_option(struct mptcp_sock * msk,sockptr_t optval,unsigned int optlen,int * val)57 static int mptcp_get_int_option(struct mptcp_sock *msk, sockptr_t optval,
58 unsigned int optlen, int *val)
59 {
60 if (optlen < sizeof(int))
61 return -EINVAL;
62
63 if (copy_from_sockptr(val, optval, sizeof(*val)))
64 return -EFAULT;
65
66 return 0;
67 }
68
mptcp_sol_socket_sync_intval(struct mptcp_sock * msk,int optname,int val)69 static void mptcp_sol_socket_sync_intval(struct mptcp_sock *msk, int optname, int val)
70 {
71 struct mptcp_subflow_context *subflow;
72 struct sock *sk = (struct sock *)msk;
73
74 lock_sock(sk);
75 sockopt_seq_inc(msk);
76
77 mptcp_for_each_subflow(msk, subflow) {
78 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
79 bool slow = lock_sock_fast(ssk);
80
81 switch (optname) {
82 case SO_DEBUG:
83 sock_valbool_flag(ssk, SOCK_DBG, !!val);
84 break;
85 case SO_KEEPALIVE:
86 if (ssk->sk_prot->keepalive)
87 ssk->sk_prot->keepalive(ssk, !!val);
88 sock_valbool_flag(ssk, SOCK_KEEPOPEN, !!val);
89 break;
90 case SO_PRIORITY:
91 ssk->sk_priority = val;
92 break;
93 case SO_SNDBUF:
94 case SO_SNDBUFFORCE:
95 ssk->sk_userlocks |= SOCK_SNDBUF_LOCK;
96 WRITE_ONCE(ssk->sk_sndbuf, sk->sk_sndbuf);
97 break;
98 case SO_RCVBUF:
99 case SO_RCVBUFFORCE:
100 ssk->sk_userlocks |= SOCK_RCVBUF_LOCK;
101 WRITE_ONCE(ssk->sk_rcvbuf, sk->sk_rcvbuf);
102 break;
103 case SO_MARK:
104 if (READ_ONCE(ssk->sk_mark) != sk->sk_mark) {
105 ssk->sk_mark = sk->sk_mark;
106 sk_dst_reset(ssk);
107 }
108 break;
109 case SO_INCOMING_CPU:
110 WRITE_ONCE(ssk->sk_incoming_cpu, val);
111 break;
112 }
113
114 subflow->setsockopt_seq = msk->setsockopt_seq;
115 unlock_sock_fast(ssk, slow);
116 }
117
118 release_sock(sk);
119 }
120
mptcp_sol_socket_intval(struct mptcp_sock * msk,int optname,int val)121 static int mptcp_sol_socket_intval(struct mptcp_sock *msk, int optname, int val)
122 {
123 sockptr_t optval = KERNEL_SOCKPTR(&val);
124 struct sock *sk = (struct sock *)msk;
125 int ret;
126
127 ret = sock_setsockopt(sk->sk_socket, SOL_SOCKET, optname,
128 optval, sizeof(val));
129 if (ret)
130 return ret;
131
132 mptcp_sol_socket_sync_intval(msk, optname, val);
133 return 0;
134 }
135
mptcp_so_incoming_cpu(struct mptcp_sock * msk,int val)136 static void mptcp_so_incoming_cpu(struct mptcp_sock *msk, int val)
137 {
138 struct sock *sk = (struct sock *)msk;
139
140 WRITE_ONCE(sk->sk_incoming_cpu, val);
141
142 mptcp_sol_socket_sync_intval(msk, SO_INCOMING_CPU, val);
143 }
144
mptcp_setsockopt_sol_socket_tstamp(struct mptcp_sock * msk,int optname,int val)145 static int mptcp_setsockopt_sol_socket_tstamp(struct mptcp_sock *msk, int optname, int val)
146 {
147 sockptr_t optval = KERNEL_SOCKPTR(&val);
148 struct mptcp_subflow_context *subflow;
149 struct sock *sk = (struct sock *)msk;
150 int ret;
151
152 ret = sock_setsockopt(sk->sk_socket, SOL_SOCKET, optname,
153 optval, sizeof(val));
154 if (ret)
155 return ret;
156
157 lock_sock(sk);
158 mptcp_for_each_subflow(msk, subflow) {
159 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
160 bool slow = lock_sock_fast(ssk);
161
162 sock_set_timestamp(sk, optname, !!val);
163 unlock_sock_fast(ssk, slow);
164 }
165
166 release_sock(sk);
167 return 0;
168 }
169
mptcp_setsockopt_sol_socket_int(struct mptcp_sock * msk,int optname,sockptr_t optval,unsigned int optlen)170 static int mptcp_setsockopt_sol_socket_int(struct mptcp_sock *msk, int optname,
171 sockptr_t optval,
172 unsigned int optlen)
173 {
174 int val, ret;
175
176 ret = mptcp_get_int_option(msk, optval, optlen, &val);
177 if (ret)
178 return ret;
179
180 switch (optname) {
181 case SO_KEEPALIVE:
182 mptcp_sol_socket_sync_intval(msk, optname, val);
183 return 0;
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
mptcp_setsockopt_sol_socket_timestamping(struct mptcp_sock * msk,int optname,sockptr_t optval,unsigned int optlen)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
mptcp_setsockopt_sol_socket_linger(struct mptcp_sock * msk,sockptr_t optval,unsigned int optlen)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
mptcp_setsockopt_sol_socket(struct mptcp_sock * msk,int optname,sockptr_t optval,unsigned int optlen)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 socket *ssock;
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 ssock = __mptcp_nmpc_socket(msk);
304 if (!ssock) {
305 release_sock(sk);
306 return -EINVAL;
307 }
308
309 ret = sock_setsockopt(ssock, SOL_SOCKET, optname, optval, optlen);
310 if (ret == 0) {
311 if (optname == SO_REUSEPORT)
312 sk->sk_reuseport = ssock->sk->sk_reuseport;
313 else if (optname == SO_REUSEADDR)
314 sk->sk_reuse = ssock->sk->sk_reuse;
315 else if (optname == SO_BINDTODEVICE)
316 sk->sk_bound_dev_if = ssock->sk->sk_bound_dev_if;
317 else if (optname == SO_BINDTOIFINDEX)
318 sk->sk_bound_dev_if = ssock->sk->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_PASSSEC:
359 case SO_RXQ_OVFL:
360 case SO_WIFI_STATUS:
361 case SO_NOFCS:
362 case SO_SELECT_ERR_QUEUE:
363 return 0;
364 }
365
366 /* SO_OOBINLINE is not supported, let's avoid the related mess
367 * SO_ATTACH_FILTER, SO_ATTACH_BPF, SO_ATTACH_REUSEPORT_CBPF,
368 * SO_DETACH_REUSEPORT_BPF, SO_DETACH_FILTER, SO_LOCK_FILTER,
369 * we must be careful with subflows
370 *
371 * SO_ATTACH_REUSEPORT_EBPF is not supported, at it checks
372 * explicitly the sk_protocol field
373 *
374 * SO_PEEK_OFF is unsupported, as it is for plain TCP
375 * SO_MAX_PACING_RATE is unsupported, we must be careful with subflows
376 * SO_CNX_ADVICE is currently unsupported, could possibly be relevant,
377 * but likely needs careful design
378 *
379 * SO_ZEROCOPY is currently unsupported, TODO in sndmsg
380 * SO_TXTIME is currently unsupported
381 */
382
383 return -EOPNOTSUPP;
384 }
385
mptcp_setsockopt_v6(struct mptcp_sock * msk,int optname,sockptr_t optval,unsigned int optlen)386 static int mptcp_setsockopt_v6(struct mptcp_sock *msk, int optname,
387 sockptr_t optval, unsigned int optlen)
388 {
389 struct sock *sk = (struct sock *)msk;
390 int ret = -EOPNOTSUPP;
391 struct socket *ssock;
392
393 switch (optname) {
394 case IPV6_V6ONLY:
395 case IPV6_TRANSPARENT:
396 case IPV6_FREEBIND:
397 lock_sock(sk);
398 ssock = __mptcp_nmpc_socket(msk);
399 if (!ssock) {
400 release_sock(sk);
401 return -EINVAL;
402 }
403
404 ret = tcp_setsockopt(ssock->sk, SOL_IPV6, optname, optval, optlen);
405 if (ret != 0) {
406 release_sock(sk);
407 return ret;
408 }
409
410 sockopt_seq_inc(msk);
411
412 switch (optname) {
413 case IPV6_V6ONLY:
414 sk->sk_ipv6only = ssock->sk->sk_ipv6only;
415 break;
416 case IPV6_TRANSPARENT:
417 inet_sk(sk)->transparent = inet_sk(ssock->sk)->transparent;
418 break;
419 case IPV6_FREEBIND:
420 inet_sk(sk)->freebind = inet_sk(ssock->sk)->freebind;
421 break;
422 }
423
424 release_sock(sk);
425 break;
426 }
427
428 return ret;
429 }
430
mptcp_supported_sockopt(int level,int optname)431 static bool mptcp_supported_sockopt(int level, int optname)
432 {
433 if (level == SOL_IP) {
434 switch (optname) {
435 /* should work fine */
436 case IP_FREEBIND:
437 case IP_TRANSPARENT:
438
439 /* the following are control cmsg related */
440 case IP_PKTINFO:
441 case IP_RECVTTL:
442 case IP_RECVTOS:
443 case IP_RECVOPTS:
444 case IP_RETOPTS:
445 case IP_PASSSEC:
446 case IP_RECVORIGDSTADDR:
447 case IP_CHECKSUM:
448 case IP_RECVFRAGSIZE:
449
450 /* common stuff that need some love */
451 case IP_TOS:
452 case IP_TTL:
453 case IP_BIND_ADDRESS_NO_PORT:
454 case IP_MTU_DISCOVER:
455 case IP_RECVERR:
456
457 /* possibly less common may deserve some love */
458 case IP_MINTTL:
459
460 /* the following is apparently a no-op for plain TCP */
461 case IP_RECVERR_RFC4884:
462 return true;
463 }
464
465 /* IP_OPTIONS is not supported, needs subflow care */
466 /* IP_HDRINCL, IP_NODEFRAG are not supported, RAW specific */
467 /* IP_MULTICAST_TTL, IP_MULTICAST_LOOP, IP_UNICAST_IF,
468 * IP_ADD_MEMBERSHIP, IP_ADD_SOURCE_MEMBERSHIP, IP_DROP_MEMBERSHIP,
469 * IP_DROP_SOURCE_MEMBERSHIP, IP_BLOCK_SOURCE, IP_UNBLOCK_SOURCE,
470 * MCAST_JOIN_GROUP, MCAST_LEAVE_GROUP MCAST_JOIN_SOURCE_GROUP,
471 * MCAST_LEAVE_SOURCE_GROUP, MCAST_BLOCK_SOURCE, MCAST_UNBLOCK_SOURCE,
472 * MCAST_MSFILTER, IP_MULTICAST_ALL are not supported, better not deal
473 * with mcast stuff
474 */
475 /* IP_IPSEC_POLICY, IP_XFRM_POLICY are nut supported, unrelated here */
476 return false;
477 }
478 if (level == SOL_IPV6) {
479 switch (optname) {
480 case IPV6_V6ONLY:
481
482 /* the following are control cmsg related */
483 case IPV6_RECVPKTINFO:
484 case IPV6_2292PKTINFO:
485 case IPV6_RECVHOPLIMIT:
486 case IPV6_2292HOPLIMIT:
487 case IPV6_RECVRTHDR:
488 case IPV6_2292RTHDR:
489 case IPV6_RECVHOPOPTS:
490 case IPV6_2292HOPOPTS:
491 case IPV6_RECVDSTOPTS:
492 case IPV6_2292DSTOPTS:
493 case IPV6_RECVTCLASS:
494 case IPV6_FLOWINFO:
495 case IPV6_RECVPATHMTU:
496 case IPV6_RECVORIGDSTADDR:
497 case IPV6_RECVFRAGSIZE:
498
499 /* the following ones need some love but are quite common */
500 case IPV6_TCLASS:
501 case IPV6_TRANSPARENT:
502 case IPV6_FREEBIND:
503 case IPV6_PKTINFO:
504 case IPV6_2292PKTOPTIONS:
505 case IPV6_UNICAST_HOPS:
506 case IPV6_MTU_DISCOVER:
507 case IPV6_MTU:
508 case IPV6_RECVERR:
509 case IPV6_FLOWINFO_SEND:
510 case IPV6_FLOWLABEL_MGR:
511 case IPV6_MINHOPCOUNT:
512 case IPV6_DONTFRAG:
513 case IPV6_AUTOFLOWLABEL:
514
515 /* the following one is a no-op for plain TCP */
516 case IPV6_RECVERR_RFC4884:
517 return true;
518 }
519
520 /* IPV6_HOPOPTS, IPV6_RTHDRDSTOPTS, IPV6_RTHDR, IPV6_DSTOPTS are
521 * not supported
522 */
523 /* IPV6_MULTICAST_HOPS, IPV6_MULTICAST_LOOP, IPV6_UNICAST_IF,
524 * IPV6_MULTICAST_IF, IPV6_ADDRFORM,
525 * IPV6_ADD_MEMBERSHIP, IPV6_DROP_MEMBERSHIP, IPV6_JOIN_ANYCAST,
526 * IPV6_LEAVE_ANYCAST, IPV6_MULTICAST_ALL, MCAST_JOIN_GROUP, MCAST_LEAVE_GROUP,
527 * MCAST_JOIN_SOURCE_GROUP, MCAST_LEAVE_SOURCE_GROUP,
528 * MCAST_BLOCK_SOURCE, MCAST_UNBLOCK_SOURCE, MCAST_MSFILTER
529 * are not supported better not deal with mcast
530 */
531 /* IPV6_ROUTER_ALERT, IPV6_ROUTER_ALERT_ISOLATE are not supported, since are evil */
532
533 /* IPV6_IPSEC_POLICY, IPV6_XFRM_POLICY are not supported */
534 /* IPV6_ADDR_PREFERENCES is not supported, we must be careful with subflows */
535 return false;
536 }
537 if (level == SOL_TCP) {
538 switch (optname) {
539 /* the following are no-op or should work just fine */
540 case TCP_THIN_DUPACK:
541 case TCP_DEFER_ACCEPT:
542
543 /* the following need some love */
544 case TCP_MAXSEG:
545 case TCP_NODELAY:
546 case TCP_THIN_LINEAR_TIMEOUTS:
547 case TCP_CONGESTION:
548 case TCP_CORK:
549 case TCP_KEEPIDLE:
550 case TCP_KEEPINTVL:
551 case TCP_KEEPCNT:
552 case TCP_SYNCNT:
553 case TCP_SAVE_SYN:
554 case TCP_LINGER2:
555 case TCP_WINDOW_CLAMP:
556 case TCP_QUICKACK:
557 case TCP_USER_TIMEOUT:
558 case TCP_TIMESTAMP:
559 case TCP_NOTSENT_LOWAT:
560 case TCP_TX_DELAY:
561 case TCP_INQ:
562 case TCP_FASTOPEN_CONNECT:
563 return true;
564 }
565
566 /* TCP_MD5SIG, TCP_MD5SIG_EXT are not supported, MD5 is not compatible with MPTCP */
567
568 /* TCP_REPAIR, TCP_REPAIR_QUEUE, TCP_QUEUE_SEQ, TCP_REPAIR_OPTIONS,
569 * TCP_REPAIR_WINDOW are not supported, better avoid this mess
570 */
571 /* TCP_FASTOPEN_KEY, TCP_FASTOPEN, TCP_FASTOPEN_NO_COOKIE,
572 * are not supported fastopen is currently unsupported
573 */
574 }
575 return false;
576 }
577
mptcp_setsockopt_sol_tcp_congestion(struct mptcp_sock * msk,sockptr_t optval,unsigned int optlen)578 static int mptcp_setsockopt_sol_tcp_congestion(struct mptcp_sock *msk, sockptr_t optval,
579 unsigned int optlen)
580 {
581 struct mptcp_subflow_context *subflow;
582 struct sock *sk = (struct sock *)msk;
583 char name[TCP_CA_NAME_MAX];
584 bool cap_net_admin;
585 int ret;
586
587 if (optlen < 1)
588 return -EINVAL;
589
590 ret = strncpy_from_sockptr(name, optval,
591 min_t(long, TCP_CA_NAME_MAX - 1, optlen));
592 if (ret < 0)
593 return -EFAULT;
594
595 name[ret] = 0;
596
597 cap_net_admin = ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN);
598
599 ret = 0;
600 lock_sock(sk);
601 sockopt_seq_inc(msk);
602 mptcp_for_each_subflow(msk, subflow) {
603 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
604 int err;
605
606 lock_sock(ssk);
607 err = tcp_set_congestion_control(ssk, name, true, cap_net_admin);
608 if (err < 0 && ret == 0)
609 ret = err;
610 subflow->setsockopt_seq = msk->setsockopt_seq;
611 release_sock(ssk);
612 }
613
614 if (ret == 0)
615 strcpy(msk->ca_name, name);
616
617 release_sock(sk);
618 return ret;
619 }
620
mptcp_setsockopt_sol_tcp_cork(struct mptcp_sock * msk,sockptr_t optval,unsigned int optlen)621 static int mptcp_setsockopt_sol_tcp_cork(struct mptcp_sock *msk, sockptr_t optval,
622 unsigned int optlen)
623 {
624 struct mptcp_subflow_context *subflow;
625 struct sock *sk = (struct sock *)msk;
626 int val;
627
628 if (optlen < sizeof(int))
629 return -EINVAL;
630
631 if (copy_from_sockptr(&val, optval, sizeof(val)))
632 return -EFAULT;
633
634 lock_sock(sk);
635 sockopt_seq_inc(msk);
636 msk->cork = !!val;
637 mptcp_for_each_subflow(msk, subflow) {
638 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
639
640 lock_sock(ssk);
641 __tcp_sock_set_cork(ssk, !!val);
642 release_sock(ssk);
643 }
644 if (!val)
645 mptcp_check_and_set_pending(sk);
646 release_sock(sk);
647
648 return 0;
649 }
650
mptcp_setsockopt_sol_tcp_nodelay(struct mptcp_sock * msk,sockptr_t optval,unsigned int optlen)651 static int mptcp_setsockopt_sol_tcp_nodelay(struct mptcp_sock *msk, sockptr_t optval,
652 unsigned int optlen)
653 {
654 struct mptcp_subflow_context *subflow;
655 struct sock *sk = (struct sock *)msk;
656 int val;
657
658 if (optlen < sizeof(int))
659 return -EINVAL;
660
661 if (copy_from_sockptr(&val, optval, sizeof(val)))
662 return -EFAULT;
663
664 lock_sock(sk);
665 sockopt_seq_inc(msk);
666 msk->nodelay = !!val;
667 mptcp_for_each_subflow(msk, subflow) {
668 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
669
670 lock_sock(ssk);
671 __tcp_sock_set_nodelay(ssk, !!val);
672 release_sock(ssk);
673 }
674 if (val)
675 mptcp_check_and_set_pending(sk);
676 release_sock(sk);
677
678 return 0;
679 }
680
mptcp_setsockopt_sol_ip_set_transparent(struct mptcp_sock * msk,int optname,sockptr_t optval,unsigned int optlen)681 static int mptcp_setsockopt_sol_ip_set_transparent(struct mptcp_sock *msk, int optname,
682 sockptr_t optval, unsigned int optlen)
683 {
684 struct sock *sk = (struct sock *)msk;
685 struct inet_sock *issk;
686 struct socket *ssock;
687 int err;
688
689 err = ip_setsockopt(sk, SOL_IP, optname, optval, optlen);
690 if (err != 0)
691 return err;
692
693 lock_sock(sk);
694
695 ssock = __mptcp_nmpc_socket(msk);
696 if (!ssock) {
697 release_sock(sk);
698 return -EINVAL;
699 }
700
701 issk = inet_sk(ssock->sk);
702
703 switch (optname) {
704 case IP_FREEBIND:
705 issk->freebind = inet_sk(sk)->freebind;
706 break;
707 case IP_TRANSPARENT:
708 issk->transparent = inet_sk(sk)->transparent;
709 break;
710 default:
711 release_sock(sk);
712 WARN_ON_ONCE(1);
713 return -EOPNOTSUPP;
714 }
715
716 sockopt_seq_inc(msk);
717 release_sock(sk);
718 return 0;
719 }
720
mptcp_setsockopt_v4_set_tos(struct mptcp_sock * msk,int optname,sockptr_t optval,unsigned int optlen)721 static int mptcp_setsockopt_v4_set_tos(struct mptcp_sock *msk, int optname,
722 sockptr_t optval, unsigned int optlen)
723 {
724 struct mptcp_subflow_context *subflow;
725 struct sock *sk = (struct sock *)msk;
726 int err, val;
727
728 err = ip_setsockopt(sk, SOL_IP, optname, optval, optlen);
729
730 if (err != 0)
731 return err;
732
733 lock_sock(sk);
734 sockopt_seq_inc(msk);
735 val = inet_sk(sk)->tos;
736 mptcp_for_each_subflow(msk, subflow) {
737 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
738
739 __ip_sock_set_tos(ssk, val);
740 }
741 release_sock(sk);
742
743 return err;
744 }
745
mptcp_setsockopt_v4(struct mptcp_sock * msk,int optname,sockptr_t optval,unsigned int optlen)746 static int mptcp_setsockopt_v4(struct mptcp_sock *msk, int optname,
747 sockptr_t optval, unsigned int optlen)
748 {
749 switch (optname) {
750 case IP_FREEBIND:
751 case IP_TRANSPARENT:
752 return mptcp_setsockopt_sol_ip_set_transparent(msk, optname, optval, optlen);
753 case IP_TOS:
754 return mptcp_setsockopt_v4_set_tos(msk, optname, optval, optlen);
755 }
756
757 return -EOPNOTSUPP;
758 }
759
mptcp_setsockopt_sol_tcp_defer(struct mptcp_sock * msk,sockptr_t optval,unsigned int optlen)760 static int mptcp_setsockopt_sol_tcp_defer(struct mptcp_sock *msk, sockptr_t optval,
761 unsigned int optlen)
762 {
763 struct socket *listener;
764
765 listener = __mptcp_nmpc_socket(msk);
766 if (!listener)
767 return 0; /* TCP_DEFER_ACCEPT does not fail */
768
769 return tcp_setsockopt(listener->sk, SOL_TCP, TCP_DEFER_ACCEPT, optval, optlen);
770 }
771
mptcp_setsockopt_sol_tcp_fastopen_connect(struct mptcp_sock * msk,sockptr_t optval,unsigned int optlen)772 static int mptcp_setsockopt_sol_tcp_fastopen_connect(struct mptcp_sock *msk, sockptr_t optval,
773 unsigned int optlen)
774 {
775 struct socket *sock;
776
777 /* Limit to first subflow */
778 sock = __mptcp_nmpc_socket(msk);
779 if (!sock)
780 return -EINVAL;
781
782 return tcp_setsockopt(sock->sk, SOL_TCP, TCP_FASTOPEN_CONNECT, optval, optlen);
783 }
784
mptcp_setsockopt_sol_tcp(struct mptcp_sock * msk,int optname,sockptr_t optval,unsigned int optlen)785 static int mptcp_setsockopt_sol_tcp(struct mptcp_sock *msk, int optname,
786 sockptr_t optval, unsigned int optlen)
787 {
788 struct sock *sk = (void *)msk;
789 int ret, val;
790
791 switch (optname) {
792 case TCP_INQ:
793 ret = mptcp_get_int_option(msk, optval, optlen, &val);
794 if (ret)
795 return ret;
796 if (val < 0 || val > 1)
797 return -EINVAL;
798
799 lock_sock(sk);
800 msk->recvmsg_inq = !!val;
801 release_sock(sk);
802 return 0;
803 case TCP_ULP:
804 return -EOPNOTSUPP;
805 case TCP_CONGESTION:
806 return mptcp_setsockopt_sol_tcp_congestion(msk, optval, optlen);
807 case TCP_CORK:
808 return mptcp_setsockopt_sol_tcp_cork(msk, optval, optlen);
809 case TCP_NODELAY:
810 return mptcp_setsockopt_sol_tcp_nodelay(msk, optval, optlen);
811 case TCP_DEFER_ACCEPT:
812 return mptcp_setsockopt_sol_tcp_defer(msk, optval, optlen);
813 case TCP_FASTOPEN_CONNECT:
814 return mptcp_setsockopt_sol_tcp_fastopen_connect(msk, optval, optlen);
815 }
816
817 return -EOPNOTSUPP;
818 }
819
mptcp_setsockopt(struct sock * sk,int level,int optname,sockptr_t optval,unsigned int optlen)820 int mptcp_setsockopt(struct sock *sk, int level, int optname,
821 sockptr_t optval, unsigned int optlen)
822 {
823 struct mptcp_sock *msk = mptcp_sk(sk);
824 struct sock *ssk;
825
826 pr_debug("msk=%p", msk);
827
828 if (level == SOL_SOCKET)
829 return mptcp_setsockopt_sol_socket(msk, optname, optval, optlen);
830
831 if (!mptcp_supported_sockopt(level, optname))
832 return -ENOPROTOOPT;
833
834 /* @@ the meaning of setsockopt() when the socket is connected and
835 * there are multiple subflows is not yet defined. It is up to the
836 * MPTCP-level socket to configure the subflows until the subflow
837 * is in TCP fallback, when TCP socket options are passed through
838 * to the one remaining subflow.
839 */
840 lock_sock(sk);
841 ssk = __mptcp_tcp_fallback(msk);
842 release_sock(sk);
843 if (ssk)
844 return tcp_setsockopt(ssk, level, optname, optval, optlen);
845
846 if (level == SOL_IP)
847 return mptcp_setsockopt_v4(msk, optname, optval, optlen);
848
849 if (level == SOL_IPV6)
850 return mptcp_setsockopt_v6(msk, optname, optval, optlen);
851
852 if (level == SOL_TCP)
853 return mptcp_setsockopt_sol_tcp(msk, optname, optval, optlen);
854
855 return -EOPNOTSUPP;
856 }
857
mptcp_getsockopt_first_sf_only(struct mptcp_sock * msk,int level,int optname,char __user * optval,int __user * optlen)858 static int mptcp_getsockopt_first_sf_only(struct mptcp_sock *msk, int level, int optname,
859 char __user *optval, int __user *optlen)
860 {
861 struct sock *sk = (struct sock *)msk;
862 struct socket *ssock;
863 int ret = -EINVAL;
864 struct sock *ssk;
865
866 lock_sock(sk);
867 ssk = msk->first;
868 if (ssk) {
869 ret = tcp_getsockopt(ssk, level, optname, optval, optlen);
870 goto out;
871 }
872
873 ssock = __mptcp_nmpc_socket(msk);
874 if (!ssock)
875 goto out;
876
877 ret = tcp_getsockopt(ssock->sk, level, optname, optval, optlen);
878
879 out:
880 release_sock(sk);
881 return ret;
882 }
883
mptcp_diag_fill_info(struct mptcp_sock * msk,struct mptcp_info * info)884 void mptcp_diag_fill_info(struct mptcp_sock *msk, struct mptcp_info *info)
885 {
886 u32 flags = 0;
887 u8 val;
888
889 memset(info, 0, sizeof(*info));
890
891 info->mptcpi_subflows = READ_ONCE(msk->pm.subflows);
892 info->mptcpi_add_addr_signal = READ_ONCE(msk->pm.add_addr_signaled);
893 info->mptcpi_add_addr_accepted = READ_ONCE(msk->pm.add_addr_accepted);
894 info->mptcpi_local_addr_used = READ_ONCE(msk->pm.local_addr_used);
895 info->mptcpi_subflows_max = mptcp_pm_get_subflows_max(msk);
896 val = mptcp_pm_get_add_addr_signal_max(msk);
897 info->mptcpi_add_addr_signal_max = val;
898 val = mptcp_pm_get_add_addr_accept_max(msk);
899 info->mptcpi_add_addr_accepted_max = val;
900 info->mptcpi_local_addr_max = mptcp_pm_get_local_addr_max(msk);
901 if (test_bit(MPTCP_FALLBACK_DONE, &msk->flags))
902 flags |= MPTCP_INFO_FLAG_FALLBACK;
903 if (READ_ONCE(msk->can_ack))
904 flags |= MPTCP_INFO_FLAG_REMOTE_KEY_RECEIVED;
905 info->mptcpi_flags = flags;
906 info->mptcpi_token = READ_ONCE(msk->token);
907 info->mptcpi_write_seq = READ_ONCE(msk->write_seq);
908 info->mptcpi_snd_una = READ_ONCE(msk->snd_una);
909 info->mptcpi_rcv_nxt = READ_ONCE(msk->ack_seq);
910 info->mptcpi_csum_enabled = READ_ONCE(msk->csum_enabled);
911 }
912 EXPORT_SYMBOL_GPL(mptcp_diag_fill_info);
913
mptcp_getsockopt_info(struct mptcp_sock * msk,char __user * optval,int __user * optlen)914 static int mptcp_getsockopt_info(struct mptcp_sock *msk, char __user *optval, int __user *optlen)
915 {
916 struct mptcp_info m_info;
917 int len;
918
919 if (get_user(len, optlen))
920 return -EFAULT;
921
922 len = min_t(unsigned int, len, sizeof(struct mptcp_info));
923
924 mptcp_diag_fill_info(msk, &m_info);
925
926 if (put_user(len, optlen))
927 return -EFAULT;
928
929 if (copy_to_user(optval, &m_info, len))
930 return -EFAULT;
931
932 return 0;
933 }
934
mptcp_put_subflow_data(struct mptcp_subflow_data * sfd,char __user * optval,u32 copied,int __user * optlen)935 static int mptcp_put_subflow_data(struct mptcp_subflow_data *sfd,
936 char __user *optval,
937 u32 copied,
938 int __user *optlen)
939 {
940 u32 copylen = min_t(u32, sfd->size_subflow_data, sizeof(*sfd));
941
942 if (copied)
943 copied += sfd->size_subflow_data;
944 else
945 copied = copylen;
946
947 if (put_user(copied, optlen))
948 return -EFAULT;
949
950 if (copy_to_user(optval, sfd, copylen))
951 return -EFAULT;
952
953 return 0;
954 }
955
mptcp_get_subflow_data(struct mptcp_subflow_data * sfd,char __user * optval,int __user * optlen)956 static int mptcp_get_subflow_data(struct mptcp_subflow_data *sfd,
957 char __user *optval, int __user *optlen)
958 {
959 int len, copylen;
960
961 if (get_user(len, optlen))
962 return -EFAULT;
963
964 /* if mptcp_subflow_data size is changed, need to adjust
965 * this function to deal with programs using old version.
966 */
967 BUILD_BUG_ON(sizeof(*sfd) != MIN_INFO_OPTLEN_SIZE);
968
969 if (len < MIN_INFO_OPTLEN_SIZE)
970 return -EINVAL;
971
972 memset(sfd, 0, sizeof(*sfd));
973
974 copylen = min_t(unsigned int, len, sizeof(*sfd));
975 if (copy_from_user(sfd, optval, copylen))
976 return -EFAULT;
977
978 /* size_subflow_data is u32, but len is signed */
979 if (sfd->size_subflow_data > INT_MAX ||
980 sfd->size_user > INT_MAX)
981 return -EINVAL;
982
983 if (sfd->size_subflow_data < MIN_INFO_OPTLEN_SIZE ||
984 sfd->size_subflow_data > len)
985 return -EINVAL;
986
987 if (sfd->num_subflows || sfd->size_kernel)
988 return -EINVAL;
989
990 return len - sfd->size_subflow_data;
991 }
992
mptcp_getsockopt_tcpinfo(struct mptcp_sock * msk,char __user * optval,int __user * optlen)993 static int mptcp_getsockopt_tcpinfo(struct mptcp_sock *msk, char __user *optval,
994 int __user *optlen)
995 {
996 struct mptcp_subflow_context *subflow;
997 struct sock *sk = &msk->sk.icsk_inet.sk;
998 unsigned int sfcount = 0, copied = 0;
999 struct mptcp_subflow_data sfd;
1000 char __user *infoptr;
1001 int len;
1002
1003 len = mptcp_get_subflow_data(&sfd, optval, optlen);
1004 if (len < 0)
1005 return len;
1006
1007 sfd.size_kernel = sizeof(struct tcp_info);
1008 sfd.size_user = min_t(unsigned int, sfd.size_user,
1009 sizeof(struct tcp_info));
1010
1011 infoptr = optval + sfd.size_subflow_data;
1012
1013 lock_sock(sk);
1014
1015 mptcp_for_each_subflow(msk, subflow) {
1016 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
1017
1018 ++sfcount;
1019
1020 if (len && len >= sfd.size_user) {
1021 struct tcp_info info;
1022
1023 tcp_get_info(ssk, &info);
1024
1025 if (copy_to_user(infoptr, &info, sfd.size_user)) {
1026 release_sock(sk);
1027 return -EFAULT;
1028 }
1029
1030 infoptr += sfd.size_user;
1031 copied += sfd.size_user;
1032 len -= sfd.size_user;
1033 }
1034 }
1035
1036 release_sock(sk);
1037
1038 sfd.num_subflows = sfcount;
1039
1040 if (mptcp_put_subflow_data(&sfd, optval, copied, optlen))
1041 return -EFAULT;
1042
1043 return 0;
1044 }
1045
mptcp_get_sub_addrs(const struct sock * sk,struct mptcp_subflow_addrs * a)1046 static void mptcp_get_sub_addrs(const struct sock *sk, struct mptcp_subflow_addrs *a)
1047 {
1048 struct inet_sock *inet = inet_sk(sk);
1049
1050 memset(a, 0, sizeof(*a));
1051
1052 if (sk->sk_family == AF_INET) {
1053 a->sin_local.sin_family = AF_INET;
1054 a->sin_local.sin_port = inet->inet_sport;
1055 a->sin_local.sin_addr.s_addr = inet->inet_rcv_saddr;
1056
1057 if (!a->sin_local.sin_addr.s_addr)
1058 a->sin_local.sin_addr.s_addr = inet->inet_saddr;
1059
1060 a->sin_remote.sin_family = AF_INET;
1061 a->sin_remote.sin_port = inet->inet_dport;
1062 a->sin_remote.sin_addr.s_addr = inet->inet_daddr;
1063 #if IS_ENABLED(CONFIG_IPV6)
1064 } else if (sk->sk_family == AF_INET6) {
1065 const struct ipv6_pinfo *np = inet6_sk(sk);
1066
1067 if (WARN_ON_ONCE(!np))
1068 return;
1069
1070 a->sin6_local.sin6_family = AF_INET6;
1071 a->sin6_local.sin6_port = inet->inet_sport;
1072
1073 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr))
1074 a->sin6_local.sin6_addr = np->saddr;
1075 else
1076 a->sin6_local.sin6_addr = sk->sk_v6_rcv_saddr;
1077
1078 a->sin6_remote.sin6_family = AF_INET6;
1079 a->sin6_remote.sin6_port = inet->inet_dport;
1080 a->sin6_remote.sin6_addr = sk->sk_v6_daddr;
1081 #endif
1082 }
1083 }
1084
mptcp_getsockopt_subflow_addrs(struct mptcp_sock * msk,char __user * optval,int __user * optlen)1085 static int mptcp_getsockopt_subflow_addrs(struct mptcp_sock *msk, char __user *optval,
1086 int __user *optlen)
1087 {
1088 struct sock *sk = &msk->sk.icsk_inet.sk;
1089 struct mptcp_subflow_context *subflow;
1090 unsigned int sfcount = 0, copied = 0;
1091 struct mptcp_subflow_data sfd;
1092 char __user *addrptr;
1093 int len;
1094
1095 len = mptcp_get_subflow_data(&sfd, optval, optlen);
1096 if (len < 0)
1097 return len;
1098
1099 sfd.size_kernel = sizeof(struct mptcp_subflow_addrs);
1100 sfd.size_user = min_t(unsigned int, sfd.size_user,
1101 sizeof(struct mptcp_subflow_addrs));
1102
1103 addrptr = optval + sfd.size_subflow_data;
1104
1105 lock_sock(sk);
1106
1107 mptcp_for_each_subflow(msk, subflow) {
1108 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
1109
1110 ++sfcount;
1111
1112 if (len && len >= sfd.size_user) {
1113 struct mptcp_subflow_addrs a;
1114
1115 mptcp_get_sub_addrs(ssk, &a);
1116
1117 if (copy_to_user(addrptr, &a, sfd.size_user)) {
1118 release_sock(sk);
1119 return -EFAULT;
1120 }
1121
1122 addrptr += sfd.size_user;
1123 copied += sfd.size_user;
1124 len -= sfd.size_user;
1125 }
1126 }
1127
1128 release_sock(sk);
1129
1130 sfd.num_subflows = sfcount;
1131
1132 if (mptcp_put_subflow_data(&sfd, optval, copied, optlen))
1133 return -EFAULT;
1134
1135 return 0;
1136 }
1137
mptcp_put_int_option(struct mptcp_sock * msk,char __user * optval,int __user * optlen,int val)1138 static int mptcp_put_int_option(struct mptcp_sock *msk, char __user *optval,
1139 int __user *optlen, int val)
1140 {
1141 int len;
1142
1143 if (get_user(len, optlen))
1144 return -EFAULT;
1145 if (len < 0)
1146 return -EINVAL;
1147
1148 if (len < sizeof(int) && len > 0 && val >= 0 && val <= 255) {
1149 unsigned char ucval = (unsigned char)val;
1150
1151 len = 1;
1152 if (put_user(len, optlen))
1153 return -EFAULT;
1154 if (copy_to_user(optval, &ucval, 1))
1155 return -EFAULT;
1156 } else {
1157 len = min_t(unsigned int, len, sizeof(int));
1158 if (put_user(len, optlen))
1159 return -EFAULT;
1160 if (copy_to_user(optval, &val, len))
1161 return -EFAULT;
1162 }
1163
1164 return 0;
1165 }
1166
mptcp_getsockopt_sol_tcp(struct mptcp_sock * msk,int optname,char __user * optval,int __user * optlen)1167 static int mptcp_getsockopt_sol_tcp(struct mptcp_sock *msk, int optname,
1168 char __user *optval, int __user *optlen)
1169 {
1170 switch (optname) {
1171 case TCP_ULP:
1172 case TCP_CONGESTION:
1173 case TCP_INFO:
1174 case TCP_CC_INFO:
1175 case TCP_DEFER_ACCEPT:
1176 case TCP_FASTOPEN_CONNECT:
1177 return mptcp_getsockopt_first_sf_only(msk, SOL_TCP, optname,
1178 optval, optlen);
1179 case TCP_INQ:
1180 return mptcp_put_int_option(msk, optval, optlen, msk->recvmsg_inq);
1181 case TCP_CORK:
1182 return mptcp_put_int_option(msk, optval, optlen, msk->cork);
1183 case TCP_NODELAY:
1184 return mptcp_put_int_option(msk, optval, optlen, msk->nodelay);
1185 }
1186 return -EOPNOTSUPP;
1187 }
1188
mptcp_getsockopt_v4(struct mptcp_sock * msk,int optname,char __user * optval,int __user * optlen)1189 static int mptcp_getsockopt_v4(struct mptcp_sock *msk, int optname,
1190 char __user *optval, int __user *optlen)
1191 {
1192 struct sock *sk = (void *)msk;
1193
1194 switch (optname) {
1195 case IP_TOS:
1196 return mptcp_put_int_option(msk, optval, optlen, inet_sk(sk)->tos);
1197 }
1198
1199 return -EOPNOTSUPP;
1200 }
1201
mptcp_getsockopt_sol_mptcp(struct mptcp_sock * msk,int optname,char __user * optval,int __user * optlen)1202 static int mptcp_getsockopt_sol_mptcp(struct mptcp_sock *msk, int optname,
1203 char __user *optval, int __user *optlen)
1204 {
1205 switch (optname) {
1206 case MPTCP_INFO:
1207 return mptcp_getsockopt_info(msk, optval, optlen);
1208 case MPTCP_TCPINFO:
1209 return mptcp_getsockopt_tcpinfo(msk, optval, optlen);
1210 case MPTCP_SUBFLOW_ADDRS:
1211 return mptcp_getsockopt_subflow_addrs(msk, optval, optlen);
1212 }
1213
1214 return -EOPNOTSUPP;
1215 }
1216
mptcp_getsockopt(struct sock * sk,int level,int optname,char __user * optval,int __user * option)1217 int mptcp_getsockopt(struct sock *sk, int level, int optname,
1218 char __user *optval, int __user *option)
1219 {
1220 struct mptcp_sock *msk = mptcp_sk(sk);
1221 struct sock *ssk;
1222
1223 pr_debug("msk=%p", msk);
1224
1225 /* @@ the meaning of setsockopt() when the socket is connected and
1226 * there are multiple subflows is not yet defined. It is up to the
1227 * MPTCP-level socket to configure the subflows until the subflow
1228 * is in TCP fallback, when socket options are passed through
1229 * to the one remaining subflow.
1230 */
1231 lock_sock(sk);
1232 ssk = __mptcp_tcp_fallback(msk);
1233 release_sock(sk);
1234 if (ssk)
1235 return tcp_getsockopt(ssk, level, optname, optval, option);
1236
1237 if (level == SOL_IP)
1238 return mptcp_getsockopt_v4(msk, optname, optval, option);
1239 if (level == SOL_TCP)
1240 return mptcp_getsockopt_sol_tcp(msk, optname, optval, option);
1241 if (level == SOL_MPTCP)
1242 return mptcp_getsockopt_sol_mptcp(msk, optname, optval, option);
1243 return -EOPNOTSUPP;
1244 }
1245
sync_socket_options(struct mptcp_sock * msk,struct sock * ssk)1246 static void sync_socket_options(struct mptcp_sock *msk, struct sock *ssk)
1247 {
1248 static const unsigned int tx_rx_locks = SOCK_RCVBUF_LOCK | SOCK_SNDBUF_LOCK;
1249 struct sock *sk = (struct sock *)msk;
1250
1251 if (ssk->sk_prot->keepalive) {
1252 if (sock_flag(sk, SOCK_KEEPOPEN))
1253 ssk->sk_prot->keepalive(ssk, 1);
1254 else
1255 ssk->sk_prot->keepalive(ssk, 0);
1256 }
1257
1258 ssk->sk_priority = sk->sk_priority;
1259 ssk->sk_bound_dev_if = sk->sk_bound_dev_if;
1260 ssk->sk_incoming_cpu = sk->sk_incoming_cpu;
1261 __ip_sock_set_tos(ssk, inet_sk(sk)->tos);
1262
1263 if (sk->sk_userlocks & tx_rx_locks) {
1264 ssk->sk_userlocks |= sk->sk_userlocks & tx_rx_locks;
1265 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)
1266 WRITE_ONCE(ssk->sk_sndbuf, sk->sk_sndbuf);
1267 if (sk->sk_userlocks & SOCK_RCVBUF_LOCK)
1268 WRITE_ONCE(ssk->sk_rcvbuf, sk->sk_rcvbuf);
1269 }
1270
1271 if (sock_flag(sk, SOCK_LINGER)) {
1272 ssk->sk_lingertime = sk->sk_lingertime;
1273 sock_set_flag(ssk, SOCK_LINGER);
1274 } else {
1275 sock_reset_flag(ssk, SOCK_LINGER);
1276 }
1277
1278 if (sk->sk_mark != ssk->sk_mark) {
1279 ssk->sk_mark = sk->sk_mark;
1280 sk_dst_reset(ssk);
1281 }
1282
1283 sock_valbool_flag(ssk, SOCK_DBG, sock_flag(sk, SOCK_DBG));
1284
1285 if (inet_csk(sk)->icsk_ca_ops != inet_csk(ssk)->icsk_ca_ops)
1286 tcp_set_congestion_control(ssk, msk->ca_name, false, true);
1287 __tcp_sock_set_cork(ssk, !!msk->cork);
1288 __tcp_sock_set_nodelay(ssk, !!msk->nodelay);
1289
1290 inet_sk(ssk)->transparent = inet_sk(sk)->transparent;
1291 inet_sk(ssk)->freebind = inet_sk(sk)->freebind;
1292 }
1293
__mptcp_sockopt_sync(struct mptcp_sock * msk,struct sock * ssk)1294 static void __mptcp_sockopt_sync(struct mptcp_sock *msk, struct sock *ssk)
1295 {
1296 bool slow = lock_sock_fast(ssk);
1297
1298 sync_socket_options(msk, ssk);
1299
1300 unlock_sock_fast(ssk, slow);
1301 }
1302
mptcp_sockopt_sync(struct mptcp_sock * msk,struct sock * ssk)1303 void mptcp_sockopt_sync(struct mptcp_sock *msk, struct sock *ssk)
1304 {
1305 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
1306
1307 msk_owned_by_me(msk);
1308
1309 if (READ_ONCE(subflow->setsockopt_seq) != msk->setsockopt_seq) {
1310 __mptcp_sockopt_sync(msk, ssk);
1311
1312 subflow->setsockopt_seq = msk->setsockopt_seq;
1313 }
1314 }
1315
mptcp_sockopt_sync_locked(struct mptcp_sock * msk,struct sock * ssk)1316 void mptcp_sockopt_sync_locked(struct mptcp_sock *msk, struct sock *ssk)
1317 {
1318 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
1319
1320 msk_owned_by_me(msk);
1321
1322 if (READ_ONCE(subflow->setsockopt_seq) != msk->setsockopt_seq) {
1323 sync_socket_options(msk, ssk);
1324
1325 subflow->setsockopt_seq = msk->setsockopt_seq;
1326 }
1327 }
1328