1 // SPDX-License-Identifier: GPL-2.0
4 * Copyright (c) 2021, Red Hat.
7 #define pr_fmt(fmt) "MPTCP: " fmt
9 #include <linux/kernel.h>
10 #include <linux/module.h>
12 #include <net/protocol.h>
14 #include <net/mptcp.h>
17 #define MIN_INFO_OPTLEN_SIZE 16
18 #define MIN_FULL_INFO_OPTLEN_SIZE 40
20 static struct sock *__mptcp_tcp_fallback(struct mptcp_sock *msk)
24 if (likely(!__mptcp_check_fallback(msk)))
30 static u32 sockopt_seq_reset(const struct sock *sk)
34 /* Highbits contain state. Allows to distinguish sockopt_seq
35 * of listener and established:
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
44 * Set High order bits to sk_state so ssk->seq == msk->seq test
48 return (u32)sk->sk_state << 24u;
51 static void sockopt_seq_inc(struct mptcp_sock *msk)
53 u32 seq = (msk->setsockopt_seq + 1) & 0x00ffffff;
55 msk->setsockopt_seq = sockopt_seq_reset((struct sock *)msk) + seq;
58 static int mptcp_get_int_option(struct mptcp_sock *msk, sockptr_t optval,
59 unsigned int optlen, int *val)
61 if (optlen < sizeof(int))
64 if (copy_from_sockptr(val, optval, sizeof(*val)))
70 static void mptcp_sol_socket_sync_intval(struct mptcp_sock *msk, int optname, int val)
72 struct mptcp_subflow_context *subflow;
73 struct sock *sk = (struct sock *)msk;
78 mptcp_for_each_subflow(msk, subflow) {
79 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
80 bool slow = lock_sock_fast(ssk);
84 sock_valbool_flag(ssk, SOCK_DBG, !!val);
87 if (ssk->sk_prot->keepalive)
88 ssk->sk_prot->keepalive(ssk, !!val);
89 sock_valbool_flag(ssk, SOCK_KEEPOPEN, !!val);
92 WRITE_ONCE(ssk->sk_priority, val);
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;
102 ssk->sk_userlocks |= SOCK_RCVBUF_LOCK;
103 WRITE_ONCE(ssk->sk_rcvbuf, sk->sk_rcvbuf);
106 if (READ_ONCE(ssk->sk_mark) != sk->sk_mark) {
107 WRITE_ONCE(ssk->sk_mark, sk->sk_mark);
111 case SO_INCOMING_CPU:
112 WRITE_ONCE(ssk->sk_incoming_cpu, val);
116 subflow->setsockopt_seq = msk->setsockopt_seq;
117 unlock_sock_fast(ssk, slow);
123 static int mptcp_sol_socket_intval(struct mptcp_sock *msk, int optname, int val)
125 sockptr_t optval = KERNEL_SOCKPTR(&val);
126 struct sock *sk = (struct sock *)msk;
129 ret = sock_setsockopt(sk->sk_socket, SOL_SOCKET, optname,
130 optval, sizeof(val));
134 mptcp_sol_socket_sync_intval(msk, optname, val);
138 static void mptcp_so_incoming_cpu(struct mptcp_sock *msk, int val)
140 struct sock *sk = (struct sock *)msk;
142 WRITE_ONCE(sk->sk_incoming_cpu, val);
144 mptcp_sol_socket_sync_intval(msk, SO_INCOMING_CPU, val);
147 static int mptcp_setsockopt_sol_socket_tstamp(struct mptcp_sock *msk, int optname, int val)
149 sockptr_t optval = KERNEL_SOCKPTR(&val);
150 struct mptcp_subflow_context *subflow;
151 struct sock *sk = (struct sock *)msk;
154 ret = sock_setsockopt(sk->sk_socket, SOL_SOCKET, optname,
155 optval, sizeof(val));
160 mptcp_for_each_subflow(msk, subflow) {
161 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
162 bool slow = lock_sock_fast(ssk);
164 sock_set_timestamp(sk, optname, !!val);
165 unlock_sock_fast(ssk, slow);
172 static int mptcp_setsockopt_sol_socket_int(struct mptcp_sock *msk, int optname,
178 ret = mptcp_get_int_option(msk, optval, optlen, &val);
184 mptcp_sol_socket_sync_intval(msk, optname, val);
193 return mptcp_sol_socket_intval(msk, optname, val);
194 case SO_INCOMING_CPU:
195 mptcp_so_incoming_cpu(msk, val);
197 case SO_TIMESTAMP_OLD:
198 case SO_TIMESTAMP_NEW:
199 case SO_TIMESTAMPNS_OLD:
200 case SO_TIMESTAMPNS_NEW:
201 return mptcp_setsockopt_sol_socket_tstamp(msk, optname, val);
207 static int mptcp_setsockopt_sol_socket_timestamping(struct mptcp_sock *msk,
212 struct mptcp_subflow_context *subflow;
213 struct sock *sk = (struct sock *)msk;
214 struct so_timestamping timestamping;
217 if (optlen == sizeof(timestamping)) {
218 if (copy_from_sockptr(×tamping, optval,
219 sizeof(timestamping)))
221 } else if (optlen == sizeof(int)) {
222 memset(×tamping, 0, sizeof(timestamping));
224 if (copy_from_sockptr(×tamping.flags, optval, sizeof(int)))
230 ret = sock_setsockopt(sk->sk_socket, SOL_SOCKET, optname,
231 KERNEL_SOCKPTR(×tamping),
232 sizeof(timestamping));
238 mptcp_for_each_subflow(msk, subflow) {
239 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
240 bool slow = lock_sock_fast(ssk);
242 sock_set_timestamping(sk, optname, timestamping);
243 unlock_sock_fast(ssk, slow);
251 static int mptcp_setsockopt_sol_socket_linger(struct mptcp_sock *msk, sockptr_t optval,
254 struct mptcp_subflow_context *subflow;
255 struct sock *sk = (struct sock *)msk;
260 if (optlen < sizeof(ling))
263 if (copy_from_sockptr(&ling, optval, sizeof(ling)))
266 kopt = KERNEL_SOCKPTR(&ling);
267 ret = sock_setsockopt(sk->sk_socket, SOL_SOCKET, SO_LINGER, kopt, sizeof(ling));
272 sockopt_seq_inc(msk);
273 mptcp_for_each_subflow(msk, subflow) {
274 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
275 bool slow = lock_sock_fast(ssk);
278 sock_reset_flag(ssk, SOCK_LINGER);
280 ssk->sk_lingertime = sk->sk_lingertime;
281 sock_set_flag(ssk, SOCK_LINGER);
284 subflow->setsockopt_seq = msk->setsockopt_seq;
285 unlock_sock_fast(ssk, slow);
292 static int mptcp_setsockopt_sol_socket(struct mptcp_sock *msk, int optname,
293 sockptr_t optval, unsigned int optlen)
295 struct sock *sk = (struct sock *)msk;
302 case SO_BINDTODEVICE:
303 case SO_BINDTOIFINDEX:
305 ssk = __mptcp_nmpc_sk(msk);
311 ret = sk_setsockopt(ssk, SOL_SOCKET, optname, optval, optlen);
313 if (optname == SO_REUSEPORT)
314 sk->sk_reuseport = ssk->sk_reuseport;
315 else if (optname == SO_REUSEADDR)
316 sk->sk_reuse = ssk->sk_reuse;
317 else if (optname == SO_BINDTODEVICE)
318 sk->sk_bound_dev_if = ssk->sk_bound_dev_if;
319 else if (optname == SO_BINDTOIFINDEX)
320 sk->sk_bound_dev_if = ssk->sk_bound_dev_if;
331 case SO_INCOMING_CPU:
333 case SO_TIMESTAMP_OLD:
334 case SO_TIMESTAMP_NEW:
335 case SO_TIMESTAMPNS_OLD:
336 case SO_TIMESTAMPNS_NEW:
337 return mptcp_setsockopt_sol_socket_int(msk, optname, optval,
339 case SO_TIMESTAMPING_OLD:
340 case SO_TIMESTAMPING_NEW:
341 return mptcp_setsockopt_sol_socket_timestamping(msk, optname,
344 return mptcp_setsockopt_sol_socket_linger(msk, optval, optlen);
346 case SO_RCVTIMEO_OLD:
347 case SO_RCVTIMEO_NEW:
348 case SO_SNDTIMEO_OLD:
349 case SO_SNDTIMEO_NEW:
351 case SO_PREFER_BUSY_POLL:
352 case SO_BUSY_POLL_BUDGET:
353 /* No need to copy: only relevant for msk */
354 return sock_setsockopt(sk->sk_socket, SOL_SOCKET, optname, optval, optlen);
365 case SO_SELECT_ERR_QUEUE:
369 /* SO_OOBINLINE is not supported, let's avoid the related mess
370 * SO_ATTACH_FILTER, SO_ATTACH_BPF, SO_ATTACH_REUSEPORT_CBPF,
371 * SO_DETACH_REUSEPORT_BPF, SO_DETACH_FILTER, SO_LOCK_FILTER,
372 * we must be careful with subflows
374 * SO_ATTACH_REUSEPORT_EBPF is not supported, at it checks
375 * explicitly the sk_protocol field
377 * SO_PEEK_OFF is unsupported, as it is for plain TCP
378 * SO_MAX_PACING_RATE is unsupported, we must be careful with subflows
379 * SO_CNX_ADVICE is currently unsupported, could possibly be relevant,
380 * but likely needs careful design
382 * SO_ZEROCOPY is currently unsupported, TODO in sndmsg
383 * SO_TXTIME is currently unsupported
389 static int mptcp_setsockopt_v6(struct mptcp_sock *msk, int optname,
390 sockptr_t optval, unsigned int optlen)
392 struct sock *sk = (struct sock *)msk;
393 int ret = -EOPNOTSUPP;
398 case IPV6_TRANSPARENT:
401 ssk = __mptcp_nmpc_sk(msk);
407 ret = tcp_setsockopt(ssk, SOL_IPV6, optname, optval, optlen);
413 sockopt_seq_inc(msk);
417 sk->sk_ipv6only = ssk->sk_ipv6only;
419 case IPV6_TRANSPARENT:
420 inet_assign_bit(TRANSPARENT, sk,
421 inet_test_bit(TRANSPARENT, ssk));
424 inet_assign_bit(FREEBIND, sk,
425 inet_test_bit(FREEBIND, ssk));
436 static bool mptcp_supported_sockopt(int level, int optname)
438 if (level == SOL_IP) {
440 /* should work fine */
444 /* the following are control cmsg related */
451 case IP_RECVORIGDSTADDR:
453 case IP_RECVFRAGSIZE:
455 /* common stuff that need some love */
458 case IP_BIND_ADDRESS_NO_PORT:
459 case IP_MTU_DISCOVER:
462 /* possibly less common may deserve some love */
465 /* the following is apparently a no-op for plain TCP */
466 case IP_RECVERR_RFC4884:
470 /* IP_OPTIONS is not supported, needs subflow care */
471 /* IP_HDRINCL, IP_NODEFRAG are not supported, RAW specific */
472 /* IP_MULTICAST_TTL, IP_MULTICAST_LOOP, IP_UNICAST_IF,
473 * IP_ADD_MEMBERSHIP, IP_ADD_SOURCE_MEMBERSHIP, IP_DROP_MEMBERSHIP,
474 * IP_DROP_SOURCE_MEMBERSHIP, IP_BLOCK_SOURCE, IP_UNBLOCK_SOURCE,
475 * MCAST_JOIN_GROUP, MCAST_LEAVE_GROUP MCAST_JOIN_SOURCE_GROUP,
476 * MCAST_LEAVE_SOURCE_GROUP, MCAST_BLOCK_SOURCE, MCAST_UNBLOCK_SOURCE,
477 * MCAST_MSFILTER, IP_MULTICAST_ALL are not supported, better not deal
480 /* IP_IPSEC_POLICY, IP_XFRM_POLICY are nut supported, unrelated here */
483 if (level == SOL_IPV6) {
487 /* the following are control cmsg related */
488 case IPV6_RECVPKTINFO:
489 case IPV6_2292PKTINFO:
490 case IPV6_RECVHOPLIMIT:
491 case IPV6_2292HOPLIMIT:
494 case IPV6_RECVHOPOPTS:
495 case IPV6_2292HOPOPTS:
496 case IPV6_RECVDSTOPTS:
497 case IPV6_2292DSTOPTS:
498 case IPV6_RECVTCLASS:
500 case IPV6_RECVPATHMTU:
501 case IPV6_RECVORIGDSTADDR:
502 case IPV6_RECVFRAGSIZE:
504 /* the following ones need some love but are quite common */
506 case IPV6_TRANSPARENT:
509 case IPV6_2292PKTOPTIONS:
510 case IPV6_UNICAST_HOPS:
511 case IPV6_MTU_DISCOVER:
514 case IPV6_FLOWINFO_SEND:
515 case IPV6_FLOWLABEL_MGR:
516 case IPV6_MINHOPCOUNT:
518 case IPV6_AUTOFLOWLABEL:
520 /* the following one is a no-op for plain TCP */
521 case IPV6_RECVERR_RFC4884:
525 /* IPV6_HOPOPTS, IPV6_RTHDRDSTOPTS, IPV6_RTHDR, IPV6_DSTOPTS are
528 /* IPV6_MULTICAST_HOPS, IPV6_MULTICAST_LOOP, IPV6_UNICAST_IF,
529 * IPV6_MULTICAST_IF, IPV6_ADDRFORM,
530 * IPV6_ADD_MEMBERSHIP, IPV6_DROP_MEMBERSHIP, IPV6_JOIN_ANYCAST,
531 * IPV6_LEAVE_ANYCAST, IPV6_MULTICAST_ALL, MCAST_JOIN_GROUP, MCAST_LEAVE_GROUP,
532 * MCAST_JOIN_SOURCE_GROUP, MCAST_LEAVE_SOURCE_GROUP,
533 * MCAST_BLOCK_SOURCE, MCAST_UNBLOCK_SOURCE, MCAST_MSFILTER
534 * are not supported better not deal with mcast
536 /* IPV6_ROUTER_ALERT, IPV6_ROUTER_ALERT_ISOLATE are not supported, since are evil */
538 /* IPV6_IPSEC_POLICY, IPV6_XFRM_POLICY are not supported */
539 /* IPV6_ADDR_PREFERENCES is not supported, we must be careful with subflows */
542 if (level == SOL_TCP) {
544 /* the following are no-op or should work just fine */
545 case TCP_THIN_DUPACK:
546 case TCP_DEFER_ACCEPT:
548 /* the following need some love */
551 case TCP_THIN_LINEAR_TIMEOUTS:
560 case TCP_WINDOW_CLAMP:
562 case TCP_USER_TIMEOUT:
564 case TCP_NOTSENT_LOWAT:
568 case TCP_FASTOPEN_CONNECT:
569 case TCP_FASTOPEN_KEY:
570 case TCP_FASTOPEN_NO_COOKIE:
574 /* TCP_MD5SIG, TCP_MD5SIG_EXT are not supported, MD5 is not compatible with MPTCP */
576 /* TCP_REPAIR, TCP_REPAIR_QUEUE, TCP_QUEUE_SEQ, TCP_REPAIR_OPTIONS,
577 * TCP_REPAIR_WINDOW are not supported, better avoid this mess
583 static int mptcp_setsockopt_sol_tcp_congestion(struct mptcp_sock *msk, sockptr_t optval,
586 struct mptcp_subflow_context *subflow;
587 struct sock *sk = (struct sock *)msk;
588 char name[TCP_CA_NAME_MAX];
595 ret = strncpy_from_sockptr(name, optval,
596 min_t(long, TCP_CA_NAME_MAX - 1, optlen));
602 cap_net_admin = ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN);
606 sockopt_seq_inc(msk);
607 mptcp_for_each_subflow(msk, subflow) {
608 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
612 err = tcp_set_congestion_control(ssk, name, true, cap_net_admin);
613 if (err < 0 && ret == 0)
615 subflow->setsockopt_seq = msk->setsockopt_seq;
620 strcpy(msk->ca_name, name);
626 static int mptcp_setsockopt_sol_tcp_cork(struct mptcp_sock *msk, sockptr_t optval,
629 struct mptcp_subflow_context *subflow;
630 struct sock *sk = (struct sock *)msk;
633 if (optlen < sizeof(int))
636 if (copy_from_sockptr(&val, optval, sizeof(val)))
640 sockopt_seq_inc(msk);
642 mptcp_for_each_subflow(msk, subflow) {
643 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
646 __tcp_sock_set_cork(ssk, !!val);
650 mptcp_check_and_set_pending(sk);
656 static int mptcp_setsockopt_sol_tcp_nodelay(struct mptcp_sock *msk, sockptr_t optval,
659 struct mptcp_subflow_context *subflow;
660 struct sock *sk = (struct sock *)msk;
663 if (optlen < sizeof(int))
666 if (copy_from_sockptr(&val, optval, sizeof(val)))
670 sockopt_seq_inc(msk);
671 msk->nodelay = !!val;
672 mptcp_for_each_subflow(msk, subflow) {
673 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
676 __tcp_sock_set_nodelay(ssk, !!val);
680 mptcp_check_and_set_pending(sk);
686 static int mptcp_setsockopt_sol_ip_set_transparent(struct mptcp_sock *msk, int optname,
687 sockptr_t optval, unsigned int optlen)
689 struct sock *sk = (struct sock *)msk;
693 err = ip_setsockopt(sk, SOL_IP, optname, optval, optlen);
699 ssk = __mptcp_nmpc_sk(msk);
707 inet_assign_bit(FREEBIND, ssk, inet_test_bit(FREEBIND, sk));
710 inet_assign_bit(TRANSPARENT, ssk,
711 inet_test_bit(TRANSPARENT, sk));
719 sockopt_seq_inc(msk);
724 static int mptcp_setsockopt_v4_set_tos(struct mptcp_sock *msk, int optname,
725 sockptr_t optval, unsigned int optlen)
727 struct mptcp_subflow_context *subflow;
728 struct sock *sk = (struct sock *)msk;
731 err = ip_setsockopt(sk, SOL_IP, optname, optval, optlen);
737 sockopt_seq_inc(msk);
738 val = READ_ONCE(inet_sk(sk)->tos);
739 mptcp_for_each_subflow(msk, subflow) {
740 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
742 __ip_sock_set_tos(ssk, val);
749 static int mptcp_setsockopt_v4(struct mptcp_sock *msk, int optname,
750 sockptr_t optval, unsigned int optlen)
755 return mptcp_setsockopt_sol_ip_set_transparent(msk, optname, optval, optlen);
757 return mptcp_setsockopt_v4_set_tos(msk, optname, optval, optlen);
763 static int mptcp_setsockopt_first_sf_only(struct mptcp_sock *msk, int level, int optname,
764 sockptr_t optval, unsigned int optlen)
766 struct sock *sk = (struct sock *)msk;
770 /* Limit to first subflow, before the connection establishment */
772 ssk = __mptcp_nmpc_sk(msk);
778 ret = tcp_setsockopt(ssk, level, optname, optval, optlen);
785 static int mptcp_setsockopt_sol_tcp(struct mptcp_sock *msk, int optname,
786 sockptr_t optval, unsigned int optlen)
788 struct sock *sk = (void *)msk;
793 ret = mptcp_get_int_option(msk, optval, optlen, &val);
796 if (val < 0 || val > 1)
800 msk->recvmsg_inq = !!val;
806 return mptcp_setsockopt_sol_tcp_congestion(msk, optval, optlen);
808 return mptcp_setsockopt_sol_tcp_cork(msk, optval, optlen);
810 return mptcp_setsockopt_sol_tcp_nodelay(msk, optval, optlen);
811 case TCP_DEFER_ACCEPT:
812 /* See tcp.c: TCP_DEFER_ACCEPT does not fail */
813 mptcp_setsockopt_first_sf_only(msk, SOL_TCP, optname, optval, optlen);
816 case TCP_FASTOPEN_CONNECT:
817 case TCP_FASTOPEN_KEY:
818 case TCP_FASTOPEN_NO_COOKIE:
819 return mptcp_setsockopt_first_sf_only(msk, SOL_TCP, optname,
826 int mptcp_setsockopt(struct sock *sk, int level, int optname,
827 sockptr_t optval, unsigned int optlen)
829 struct mptcp_sock *msk = mptcp_sk(sk);
832 pr_debug("msk=%p", msk);
834 if (level == SOL_SOCKET)
835 return mptcp_setsockopt_sol_socket(msk, optname, optval, optlen);
837 if (!mptcp_supported_sockopt(level, optname))
840 /* @@ the meaning of setsockopt() when the socket is connected and
841 * there are multiple subflows is not yet defined. It is up to the
842 * MPTCP-level socket to configure the subflows until the subflow
843 * is in TCP fallback, when TCP socket options are passed through
844 * to the one remaining subflow.
847 ssk = __mptcp_tcp_fallback(msk);
850 return tcp_setsockopt(ssk, level, optname, optval, optlen);
853 return mptcp_setsockopt_v4(msk, optname, optval, optlen);
855 if (level == SOL_IPV6)
856 return mptcp_setsockopt_v6(msk, optname, optval, optlen);
858 if (level == SOL_TCP)
859 return mptcp_setsockopt_sol_tcp(msk, optname, optval, optlen);
864 static int mptcp_getsockopt_first_sf_only(struct mptcp_sock *msk, int level, int optname,
865 char __user *optval, int __user *optlen)
867 struct sock *sk = (struct sock *)msk;
874 ret = tcp_getsockopt(ssk, level, optname, optval, optlen);
878 ssk = __mptcp_nmpc_sk(msk);
884 ret = tcp_getsockopt(ssk, level, optname, optval, optlen);
891 void mptcp_diag_fill_info(struct mptcp_sock *msk, struct mptcp_info *info)
893 struct sock *sk = (struct sock *)msk;
897 memset(info, 0, sizeof(*info));
899 info->mptcpi_subflows = READ_ONCE(msk->pm.subflows);
900 info->mptcpi_add_addr_signal = READ_ONCE(msk->pm.add_addr_signaled);
901 info->mptcpi_add_addr_accepted = READ_ONCE(msk->pm.add_addr_accepted);
902 info->mptcpi_local_addr_used = READ_ONCE(msk->pm.local_addr_used);
904 if (inet_sk_state_load(sk) == TCP_LISTEN)
907 /* The following limits only make sense for the in-kernel PM */
908 if (mptcp_pm_is_kernel(msk)) {
909 info->mptcpi_subflows_max =
910 mptcp_pm_get_subflows_max(msk);
911 info->mptcpi_add_addr_signal_max =
912 mptcp_pm_get_add_addr_signal_max(msk);
913 info->mptcpi_add_addr_accepted_max =
914 mptcp_pm_get_add_addr_accept_max(msk);
915 info->mptcpi_local_addr_max =
916 mptcp_pm_get_local_addr_max(msk);
919 if (__mptcp_check_fallback(msk))
920 flags |= MPTCP_INFO_FLAG_FALLBACK;
921 if (READ_ONCE(msk->can_ack))
922 flags |= MPTCP_INFO_FLAG_REMOTE_KEY_RECEIVED;
923 info->mptcpi_flags = flags;
925 info->mptcpi_snd_una = msk->snd_una;
926 info->mptcpi_rcv_nxt = msk->ack_seq;
927 info->mptcpi_bytes_acked = msk->bytes_acked;
928 mptcp_data_unlock(sk);
930 slow = lock_sock_fast(sk);
931 info->mptcpi_csum_enabled = msk->csum_enabled;
932 info->mptcpi_token = msk->token;
933 info->mptcpi_write_seq = msk->write_seq;
934 info->mptcpi_retransmits = inet_csk(sk)->icsk_retransmits;
935 info->mptcpi_bytes_sent = msk->bytes_sent;
936 info->mptcpi_bytes_received = msk->bytes_received;
937 info->mptcpi_bytes_retrans = msk->bytes_retrans;
938 unlock_sock_fast(sk, slow);
940 EXPORT_SYMBOL_GPL(mptcp_diag_fill_info);
942 static int mptcp_getsockopt_info(struct mptcp_sock *msk, char __user *optval, int __user *optlen)
944 struct mptcp_info m_info;
947 if (get_user(len, optlen))
950 len = min_t(unsigned int, len, sizeof(struct mptcp_info));
952 mptcp_diag_fill_info(msk, &m_info);
954 if (put_user(len, optlen))
957 if (copy_to_user(optval, &m_info, len))
963 static int mptcp_put_subflow_data(struct mptcp_subflow_data *sfd,
968 u32 copylen = min_t(u32, sfd->size_subflow_data, sizeof(*sfd));
971 copied += sfd->size_subflow_data;
975 if (put_user(copied, optlen))
978 if (copy_to_user(optval, sfd, copylen))
984 static int mptcp_get_subflow_data(struct mptcp_subflow_data *sfd,
990 if (get_user(len, optlen))
993 /* if mptcp_subflow_data size is changed, need to adjust
994 * this function to deal with programs using old version.
996 BUILD_BUG_ON(sizeof(*sfd) != MIN_INFO_OPTLEN_SIZE);
998 if (len < MIN_INFO_OPTLEN_SIZE)
1001 memset(sfd, 0, sizeof(*sfd));
1003 copylen = min_t(unsigned int, len, sizeof(*sfd));
1004 if (copy_from_user(sfd, optval, copylen))
1007 /* size_subflow_data is u32, but len is signed */
1008 if (sfd->size_subflow_data > INT_MAX ||
1009 sfd->size_user > INT_MAX)
1012 if (sfd->size_subflow_data < MIN_INFO_OPTLEN_SIZE ||
1013 sfd->size_subflow_data > len)
1016 if (sfd->num_subflows || sfd->size_kernel)
1019 return len - sfd->size_subflow_data;
1022 static int mptcp_getsockopt_tcpinfo(struct mptcp_sock *msk, char __user *optval,
1025 struct mptcp_subflow_context *subflow;
1026 struct sock *sk = (struct sock *)msk;
1027 unsigned int sfcount = 0, copied = 0;
1028 struct mptcp_subflow_data sfd;
1029 char __user *infoptr;
1032 len = mptcp_get_subflow_data(&sfd, optval, optlen);
1036 sfd.size_kernel = sizeof(struct tcp_info);
1037 sfd.size_user = min_t(unsigned int, sfd.size_user,
1038 sizeof(struct tcp_info));
1040 infoptr = optval + sfd.size_subflow_data;
1044 mptcp_for_each_subflow(msk, subflow) {
1045 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
1049 if (len && len >= sfd.size_user) {
1050 struct tcp_info info;
1052 tcp_get_info(ssk, &info);
1054 if (copy_to_user(infoptr, &info, sfd.size_user)) {
1059 infoptr += sfd.size_user;
1060 copied += sfd.size_user;
1061 len -= sfd.size_user;
1067 sfd.num_subflows = sfcount;
1069 if (mptcp_put_subflow_data(&sfd, optval, copied, optlen))
1075 static void mptcp_get_sub_addrs(const struct sock *sk, struct mptcp_subflow_addrs *a)
1077 const struct inet_sock *inet = inet_sk(sk);
1079 memset(a, 0, sizeof(*a));
1081 if (sk->sk_family == AF_INET) {
1082 a->sin_local.sin_family = AF_INET;
1083 a->sin_local.sin_port = inet->inet_sport;
1084 a->sin_local.sin_addr.s_addr = inet->inet_rcv_saddr;
1086 if (!a->sin_local.sin_addr.s_addr)
1087 a->sin_local.sin_addr.s_addr = inet->inet_saddr;
1089 a->sin_remote.sin_family = AF_INET;
1090 a->sin_remote.sin_port = inet->inet_dport;
1091 a->sin_remote.sin_addr.s_addr = inet->inet_daddr;
1092 #if IS_ENABLED(CONFIG_IPV6)
1093 } else if (sk->sk_family == AF_INET6) {
1094 const struct ipv6_pinfo *np = inet6_sk(sk);
1096 if (WARN_ON_ONCE(!np))
1099 a->sin6_local.sin6_family = AF_INET6;
1100 a->sin6_local.sin6_port = inet->inet_sport;
1102 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr))
1103 a->sin6_local.sin6_addr = np->saddr;
1105 a->sin6_local.sin6_addr = sk->sk_v6_rcv_saddr;
1107 a->sin6_remote.sin6_family = AF_INET6;
1108 a->sin6_remote.sin6_port = inet->inet_dport;
1109 a->sin6_remote.sin6_addr = sk->sk_v6_daddr;
1114 static int mptcp_getsockopt_subflow_addrs(struct mptcp_sock *msk, char __user *optval,
1117 struct mptcp_subflow_context *subflow;
1118 struct sock *sk = (struct sock *)msk;
1119 unsigned int sfcount = 0, copied = 0;
1120 struct mptcp_subflow_data sfd;
1121 char __user *addrptr;
1124 len = mptcp_get_subflow_data(&sfd, optval, optlen);
1128 sfd.size_kernel = sizeof(struct mptcp_subflow_addrs);
1129 sfd.size_user = min_t(unsigned int, sfd.size_user,
1130 sizeof(struct mptcp_subflow_addrs));
1132 addrptr = optval + sfd.size_subflow_data;
1136 mptcp_for_each_subflow(msk, subflow) {
1137 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
1141 if (len && len >= sfd.size_user) {
1142 struct mptcp_subflow_addrs a;
1144 mptcp_get_sub_addrs(ssk, &a);
1146 if (copy_to_user(addrptr, &a, sfd.size_user)) {
1151 addrptr += sfd.size_user;
1152 copied += sfd.size_user;
1153 len -= sfd.size_user;
1159 sfd.num_subflows = sfcount;
1161 if (mptcp_put_subflow_data(&sfd, optval, copied, optlen))
1167 static int mptcp_get_full_info(struct mptcp_full_info *mfi,
1168 char __user *optval,
1173 BUILD_BUG_ON(offsetof(struct mptcp_full_info, mptcp_info) !=
1174 MIN_FULL_INFO_OPTLEN_SIZE);
1176 if (get_user(len, optlen))
1179 if (len < MIN_FULL_INFO_OPTLEN_SIZE)
1182 memset(mfi, 0, sizeof(*mfi));
1183 if (copy_from_user(mfi, optval, MIN_FULL_INFO_OPTLEN_SIZE))
1186 if (mfi->size_tcpinfo_kernel ||
1187 mfi->size_sfinfo_kernel ||
1191 if (mfi->size_sfinfo_user > INT_MAX ||
1192 mfi->size_tcpinfo_user > INT_MAX)
1195 return len - MIN_FULL_INFO_OPTLEN_SIZE;
1198 static int mptcp_put_full_info(struct mptcp_full_info *mfi,
1199 char __user *optval,
1203 copylen += MIN_FULL_INFO_OPTLEN_SIZE;
1204 if (put_user(copylen, optlen))
1207 if (copy_to_user(optval, mfi, copylen))
1212 static int mptcp_getsockopt_full_info(struct mptcp_sock *msk, char __user *optval,
1215 unsigned int sfcount = 0, copylen = 0;
1216 struct mptcp_subflow_context *subflow;
1217 struct sock *sk = (struct sock *)msk;
1218 void __user *tcpinfoptr, *sfinfoptr;
1219 struct mptcp_full_info mfi;
1222 len = mptcp_get_full_info(&mfi, optval, optlen);
1226 /* don't bother filling the mptcp info if there is not enough
1227 * user-space-provided storage
1230 mptcp_diag_fill_info(msk, &mfi.mptcp_info);
1231 copylen += min_t(unsigned int, len, sizeof(struct mptcp_info));
1234 mfi.size_tcpinfo_kernel = sizeof(struct tcp_info);
1235 mfi.size_tcpinfo_user = min_t(unsigned int, mfi.size_tcpinfo_user,
1236 sizeof(struct tcp_info));
1237 sfinfoptr = u64_to_user_ptr(mfi.subflow_info);
1238 mfi.size_sfinfo_kernel = sizeof(struct mptcp_subflow_info);
1239 mfi.size_sfinfo_user = min_t(unsigned int, mfi.size_sfinfo_user,
1240 sizeof(struct mptcp_subflow_info));
1241 tcpinfoptr = u64_to_user_ptr(mfi.tcp_info);
1244 mptcp_for_each_subflow(msk, subflow) {
1245 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
1246 struct mptcp_subflow_info sfinfo;
1247 struct tcp_info tcp_info;
1249 if (sfcount++ >= mfi.size_arrays_user)
1252 /* fetch addr/tcp_info only if the user space buffers
1255 memset(&sfinfo, 0, sizeof(sfinfo));
1256 sfinfo.id = subflow->subflow_id;
1257 if (mfi.size_sfinfo_user >
1258 offsetof(struct mptcp_subflow_info, addrs))
1259 mptcp_get_sub_addrs(ssk, &sfinfo.addrs);
1260 if (copy_to_user(sfinfoptr, &sfinfo, mfi.size_sfinfo_user))
1263 if (mfi.size_tcpinfo_user) {
1264 tcp_get_info(ssk, &tcp_info);
1265 if (copy_to_user(tcpinfoptr, &tcp_info,
1266 mfi.size_tcpinfo_user))
1270 tcpinfoptr += mfi.size_tcpinfo_user;
1271 sfinfoptr += mfi.size_sfinfo_user;
1275 mfi.num_subflows = sfcount;
1276 if (mptcp_put_full_info(&mfi, optval, copylen, optlen))
1286 static int mptcp_put_int_option(struct mptcp_sock *msk, char __user *optval,
1287 int __user *optlen, int val)
1291 if (get_user(len, optlen))
1296 if (len < sizeof(int) && len > 0 && val >= 0 && val <= 255) {
1297 unsigned char ucval = (unsigned char)val;
1300 if (put_user(len, optlen))
1302 if (copy_to_user(optval, &ucval, 1))
1305 len = min_t(unsigned int, len, sizeof(int));
1306 if (put_user(len, optlen))
1308 if (copy_to_user(optval, &val, len))
1315 static int mptcp_getsockopt_sol_tcp(struct mptcp_sock *msk, int optname,
1316 char __user *optval, int __user *optlen)
1320 case TCP_CONGESTION:
1323 case TCP_DEFER_ACCEPT:
1325 case TCP_FASTOPEN_CONNECT:
1326 case TCP_FASTOPEN_KEY:
1327 case TCP_FASTOPEN_NO_COOKIE:
1328 return mptcp_getsockopt_first_sf_only(msk, SOL_TCP, optname,
1331 return mptcp_put_int_option(msk, optval, optlen, msk->recvmsg_inq);
1333 return mptcp_put_int_option(msk, optval, optlen, msk->cork);
1335 return mptcp_put_int_option(msk, optval, optlen, msk->nodelay);
1340 static int mptcp_getsockopt_v4(struct mptcp_sock *msk, int optname,
1341 char __user *optval, int __user *optlen)
1343 struct sock *sk = (void *)msk;
1347 return mptcp_put_int_option(msk, optval, optlen, READ_ONCE(inet_sk(sk)->tos));
1353 static int mptcp_getsockopt_sol_mptcp(struct mptcp_sock *msk, int optname,
1354 char __user *optval, int __user *optlen)
1358 return mptcp_getsockopt_info(msk, optval, optlen);
1359 case MPTCP_FULL_INFO:
1360 return mptcp_getsockopt_full_info(msk, optval, optlen);
1362 return mptcp_getsockopt_tcpinfo(msk, optval, optlen);
1363 case MPTCP_SUBFLOW_ADDRS:
1364 return mptcp_getsockopt_subflow_addrs(msk, optval, optlen);
1370 int mptcp_getsockopt(struct sock *sk, int level, int optname,
1371 char __user *optval, int __user *option)
1373 struct mptcp_sock *msk = mptcp_sk(sk);
1376 pr_debug("msk=%p", msk);
1378 /* @@ the meaning of setsockopt() when the socket is connected and
1379 * there are multiple subflows is not yet defined. It is up to the
1380 * MPTCP-level socket to configure the subflows until the subflow
1381 * is in TCP fallback, when socket options are passed through
1382 * to the one remaining subflow.
1385 ssk = __mptcp_tcp_fallback(msk);
1388 return tcp_getsockopt(ssk, level, optname, optval, option);
1390 if (level == SOL_IP)
1391 return mptcp_getsockopt_v4(msk, optname, optval, option);
1392 if (level == SOL_TCP)
1393 return mptcp_getsockopt_sol_tcp(msk, optname, optval, option);
1394 if (level == SOL_MPTCP)
1395 return mptcp_getsockopt_sol_mptcp(msk, optname, optval, option);
1399 static void sync_socket_options(struct mptcp_sock *msk, struct sock *ssk)
1401 static const unsigned int tx_rx_locks = SOCK_RCVBUF_LOCK | SOCK_SNDBUF_LOCK;
1402 struct sock *sk = (struct sock *)msk;
1404 if (ssk->sk_prot->keepalive) {
1405 if (sock_flag(sk, SOCK_KEEPOPEN))
1406 ssk->sk_prot->keepalive(ssk, 1);
1408 ssk->sk_prot->keepalive(ssk, 0);
1411 ssk->sk_priority = sk->sk_priority;
1412 ssk->sk_bound_dev_if = sk->sk_bound_dev_if;
1413 ssk->sk_incoming_cpu = sk->sk_incoming_cpu;
1414 ssk->sk_ipv6only = sk->sk_ipv6only;
1415 __ip_sock_set_tos(ssk, inet_sk(sk)->tos);
1417 if (sk->sk_userlocks & tx_rx_locks) {
1418 ssk->sk_userlocks |= sk->sk_userlocks & tx_rx_locks;
1419 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) {
1420 WRITE_ONCE(ssk->sk_sndbuf, sk->sk_sndbuf);
1421 mptcp_subflow_ctx(ssk)->cached_sndbuf = sk->sk_sndbuf;
1423 if (sk->sk_userlocks & SOCK_RCVBUF_LOCK)
1424 WRITE_ONCE(ssk->sk_rcvbuf, sk->sk_rcvbuf);
1427 if (sock_flag(sk, SOCK_LINGER)) {
1428 ssk->sk_lingertime = sk->sk_lingertime;
1429 sock_set_flag(ssk, SOCK_LINGER);
1431 sock_reset_flag(ssk, SOCK_LINGER);
1434 if (sk->sk_mark != ssk->sk_mark) {
1435 ssk->sk_mark = sk->sk_mark;
1439 sock_valbool_flag(ssk, SOCK_DBG, sock_flag(sk, SOCK_DBG));
1441 if (inet_csk(sk)->icsk_ca_ops != inet_csk(ssk)->icsk_ca_ops)
1442 tcp_set_congestion_control(ssk, msk->ca_name, false, true);
1443 __tcp_sock_set_cork(ssk, !!msk->cork);
1444 __tcp_sock_set_nodelay(ssk, !!msk->nodelay);
1446 inet_assign_bit(TRANSPARENT, ssk, inet_test_bit(TRANSPARENT, sk));
1447 inet_assign_bit(FREEBIND, ssk, inet_test_bit(FREEBIND, sk));
1450 void mptcp_sockopt_sync_locked(struct mptcp_sock *msk, struct sock *ssk)
1452 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
1454 msk_owned_by_me(msk);
1456 ssk->sk_rcvlowat = 0;
1458 /* subflows must ignore any latency-related settings: will not affect
1459 * the user-space - only the msk is relevant - but will foul the
1462 tcp_sk(ssk)->notsent_lowat = UINT_MAX;
1464 if (READ_ONCE(subflow->setsockopt_seq) != msk->setsockopt_seq) {
1465 sync_socket_options(msk, ssk);
1467 subflow->setsockopt_seq = msk->setsockopt_seq;
1471 /* unfortunately this is different enough from the tcp version so
1472 * that we can't factor it out
1474 int mptcp_set_rcvlowat(struct sock *sk, int val)
1476 struct mptcp_subflow_context *subflow;
1479 if (sk->sk_userlocks & SOCK_RCVBUF_LOCK)
1480 cap = sk->sk_rcvbuf >> 1;
1482 cap = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_rmem[2]) >> 1;
1483 val = min(val, cap);
1484 WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1486 /* Check if we need to signal EPOLLIN right now */
1487 if (mptcp_epollin_ready(sk))
1488 sk->sk_data_ready(sk);
1490 if (sk->sk_userlocks & SOCK_RCVBUF_LOCK)
1493 space = __tcp_space_from_win(mptcp_sk(sk)->scaling_ratio, val);
1494 if (space <= sk->sk_rcvbuf)
1497 /* propagate the rcvbuf changes to all the subflows */
1498 WRITE_ONCE(sk->sk_rcvbuf, space);
1499 mptcp_for_each_subflow(mptcp_sk(sk), subflow) {
1500 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
1503 slow = lock_sock_fast(ssk);
1504 WRITE_ONCE(ssk->sk_rcvbuf, space);
1505 tcp_sk(ssk)->window_clamp = val;
1506 unlock_sock_fast(ssk, slow);