diff options
Diffstat (limited to '')
| -rw-r--r-- | net/mptcp/sockopt.c | 1338 |
1 files changed, 1338 insertions, 0 deletions
diff --git a/net/mptcp/sockopt.c b/net/mptcp/sockopt.c new file mode 100644 index 000000000..30374fd44 --- /dev/null +++ b/net/mptcp/sockopt.c @@ -0,0 +1,1338 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Multipath TCP + * + * Copyright (c) 2021, Red Hat. + */ + +#define pr_fmt(fmt) "MPTCP: " fmt + +#include <linux/kernel.h> +#include <linux/module.h> +#include <net/sock.h> +#include <net/protocol.h> +#include <net/tcp.h> +#include <net/mptcp.h> +#include "protocol.h" + +#define MIN_INFO_OPTLEN_SIZE 16 + +static struct sock *__mptcp_tcp_fallback(struct mptcp_sock *msk) +{ + sock_owned_by_me((const struct sock *)msk); + + if (likely(!__mptcp_check_fallback(msk))) + return NULL; + + return msk->first; +} + +static u32 sockopt_seq_reset(const struct sock *sk) +{ + sock_owned_by_me(sk); + + /* Highbits contain state. Allows to distinguish sockopt_seq + * of listener and established: + * s0 = new_listener() + * sockopt(s0) - seq is 1 + * s1 = accept(s0) - s1 inherits seq 1 if listener sk (s0) + * sockopt(s0) - seq increments to 2 on s0 + * sockopt(s1) // seq increments to 2 on s1 (different option) + * new ssk completes join, inherits options from s0 // seq 2 + * Needs sync from mptcp join logic, but ssk->seq == msk->seq + * + * Set High order bits to sk_state so ssk->seq == msk->seq test + * will fail. + */ + + return (u32)sk->sk_state << 24u; +} + +static void sockopt_seq_inc(struct mptcp_sock *msk) +{ + u32 seq = (msk->setsockopt_seq + 1) & 0x00ffffff; + + msk->setsockopt_seq = sockopt_seq_reset((struct sock *)msk) + seq; +} + +static int mptcp_get_int_option(struct mptcp_sock *msk, sockptr_t optval, + unsigned int optlen, int *val) +{ + if (optlen < sizeof(int)) + return -EINVAL; + + if (copy_from_sockptr(val, optval, sizeof(*val))) + return -EFAULT; + + return 0; +} + +static void mptcp_sol_socket_sync_intval(struct mptcp_sock *msk, int optname, int val) +{ + struct mptcp_subflow_context *subflow; + struct sock *sk = (struct sock *)msk; + + lock_sock(sk); + sockopt_seq_inc(msk); + + mptcp_for_each_subflow(msk, subflow) { + struct sock *ssk = mptcp_subflow_tcp_sock(subflow); + bool slow = lock_sock_fast(ssk); + + switch (optname) { + case SO_DEBUG: + sock_valbool_flag(ssk, SOCK_DBG, !!val); + break; + case SO_KEEPALIVE: + if (ssk->sk_prot->keepalive) + ssk->sk_prot->keepalive(ssk, !!val); + sock_valbool_flag(ssk, SOCK_KEEPOPEN, !!val); + break; + case SO_PRIORITY: + ssk->sk_priority = val; + break; + case SO_SNDBUF: + case SO_SNDBUFFORCE: + ssk->sk_userlocks |= SOCK_SNDBUF_LOCK; + WRITE_ONCE(ssk->sk_sndbuf, sk->sk_sndbuf); + break; + case SO_RCVBUF: + case SO_RCVBUFFORCE: + ssk->sk_userlocks |= SOCK_RCVBUF_LOCK; + WRITE_ONCE(ssk->sk_rcvbuf, sk->sk_rcvbuf); + break; + case SO_MARK: + if (READ_ONCE(ssk->sk_mark) != sk->sk_mark) { + WRITE_ONCE(ssk->sk_mark, sk->sk_mark); + sk_dst_reset(ssk); + } + break; + case SO_INCOMING_CPU: + WRITE_ONCE(ssk->sk_incoming_cpu, val); + break; + } + + subflow->setsockopt_seq = msk->setsockopt_seq; + unlock_sock_fast(ssk, slow); + } + + release_sock(sk); +} + +static int mptcp_sol_socket_intval(struct mptcp_sock *msk, int optname, int val) +{ + sockptr_t optval = KERNEL_SOCKPTR(&val); + struct sock *sk = (struct sock *)msk; + int ret; + + ret = sock_setsockopt(sk->sk_socket, SOL_SOCKET, optname, + optval, sizeof(val)); + if (ret) + return ret; + + mptcp_sol_socket_sync_intval(msk, optname, val); + return 0; +} + +static void mptcp_so_incoming_cpu(struct mptcp_sock *msk, int val) +{ + struct sock *sk = (struct sock *)msk; + + WRITE_ONCE(sk->sk_incoming_cpu, val); + + mptcp_sol_socket_sync_intval(msk, SO_INCOMING_CPU, val); +} + +static int mptcp_setsockopt_sol_socket_tstamp(struct mptcp_sock *msk, int optname, int val) +{ + sockptr_t optval = KERNEL_SOCKPTR(&val); + struct mptcp_subflow_context *subflow; + struct sock *sk = (struct sock *)msk; + int ret; + + ret = sock_setsockopt(sk->sk_socket, SOL_SOCKET, optname, + optval, sizeof(val)); + if (ret) + return ret; + + lock_sock(sk); + mptcp_for_each_subflow(msk, subflow) { + struct sock *ssk = mptcp_subflow_tcp_sock(subflow); + bool slow = lock_sock_fast(ssk); + + sock_set_timestamp(sk, optname, !!val); + unlock_sock_fast(ssk, slow); + } + + release_sock(sk); + return 0; +} + +static int mptcp_setsockopt_sol_socket_int(struct mptcp_sock *msk, int optname, + sockptr_t optval, + unsigned int optlen) +{ + int val, ret; + + ret = mptcp_get_int_option(msk, optval, optlen, &val); + if (ret) + return ret; + + switch (optname) { + case SO_KEEPALIVE: + mptcp_sol_socket_sync_intval(msk, optname, val); + return 0; + case SO_DEBUG: + case SO_MARK: + case SO_PRIORITY: + case SO_SNDBUF: + case SO_SNDBUFFORCE: + case SO_RCVBUF: + case SO_RCVBUFFORCE: + return mptcp_sol_socket_intval(msk, optname, val); + case SO_INCOMING_CPU: + mptcp_so_incoming_cpu(msk, val); + return 0; + case SO_TIMESTAMP_OLD: + case SO_TIMESTAMP_NEW: + case SO_TIMESTAMPNS_OLD: + case SO_TIMESTAMPNS_NEW: + return mptcp_setsockopt_sol_socket_tstamp(msk, optname, val); + } + + return -ENOPROTOOPT; +} + +static int mptcp_setsockopt_sol_socket_timestamping(struct mptcp_sock *msk, + int optname, + sockptr_t optval, + unsigned int optlen) +{ + struct mptcp_subflow_context *subflow; + struct sock *sk = (struct sock *)msk; + struct so_timestamping timestamping; + int ret; + + if (optlen == sizeof(timestamping)) { + if (copy_from_sockptr(×tamping, optval, + sizeof(timestamping))) + return -EFAULT; + } else if (optlen == sizeof(int)) { + memset(×tamping, 0, sizeof(timestamping)); + + if (copy_from_sockptr(×tamping.flags, optval, sizeof(int))) + return -EFAULT; + } else { + return -EINVAL; + } + + ret = sock_setsockopt(sk->sk_socket, SOL_SOCKET, optname, + KERNEL_SOCKPTR(×tamping), + sizeof(timestamping)); + if (ret) + return ret; + + lock_sock(sk); + + mptcp_for_each_subflow(msk, subflow) { + struct sock *ssk = mptcp_subflow_tcp_sock(subflow); + bool slow = lock_sock_fast(ssk); + + sock_set_timestamping(sk, optname, timestamping); + unlock_sock_fast(ssk, slow); + } + + release_sock(sk); + + return 0; +} + +static int mptcp_setsockopt_sol_socket_linger(struct mptcp_sock *msk, sockptr_t optval, + unsigned int optlen) +{ + struct mptcp_subflow_context *subflow; + struct sock *sk = (struct sock *)msk; + struct linger ling; + sockptr_t kopt; + int ret; + + if (optlen < sizeof(ling)) + return -EINVAL; + + if (copy_from_sockptr(&ling, optval, sizeof(ling))) + return -EFAULT; + + kopt = KERNEL_SOCKPTR(&ling); + ret = sock_setsockopt(sk->sk_socket, SOL_SOCKET, SO_LINGER, kopt, sizeof(ling)); + if (ret) + return ret; + + lock_sock(sk); + sockopt_seq_inc(msk); + mptcp_for_each_subflow(msk, subflow) { + struct sock *ssk = mptcp_subflow_tcp_sock(subflow); + bool slow = lock_sock_fast(ssk); + + if (!ling.l_onoff) { + sock_reset_flag(ssk, SOCK_LINGER); + } else { + ssk->sk_lingertime = sk->sk_lingertime; + sock_set_flag(ssk, SOCK_LINGER); + } + + subflow->setsockopt_seq = msk->setsockopt_seq; + unlock_sock_fast(ssk, slow); + } + + release_sock(sk); + return 0; +} + +static int mptcp_setsockopt_sol_socket(struct mptcp_sock *msk, int optname, + sockptr_t optval, unsigned int optlen) +{ + struct sock *sk = (struct sock *)msk; + struct socket *ssock; + int ret; + + switch (optname) { + case SO_REUSEPORT: + case SO_REUSEADDR: + case SO_BINDTODEVICE: + case SO_BINDTOIFINDEX: + lock_sock(sk); + ssock = __mptcp_nmpc_socket(msk); + if (!ssock) { + release_sock(sk); + return -EINVAL; + } + + ret = sock_setsockopt(ssock, SOL_SOCKET, optname, optval, optlen); + if (ret == 0) { + if (optname == SO_REUSEPORT) + sk->sk_reuseport = ssock->sk->sk_reuseport; + else if (optname == SO_REUSEADDR) + sk->sk_reuse = ssock->sk->sk_reuse; + else if (optname == SO_BINDTODEVICE) + sk->sk_bound_dev_if = ssock->sk->sk_bound_dev_if; + else if (optname == SO_BINDTOIFINDEX) + sk->sk_bound_dev_if = ssock->sk->sk_bound_dev_if; + } + release_sock(sk); + return ret; + case SO_KEEPALIVE: + case SO_PRIORITY: + case SO_SNDBUF: + case SO_SNDBUFFORCE: + case SO_RCVBUF: + case SO_RCVBUFFORCE: + case SO_MARK: + case SO_INCOMING_CPU: + case SO_DEBUG: + case SO_TIMESTAMP_OLD: + case SO_TIMESTAMP_NEW: + case SO_TIMESTAMPNS_OLD: + case SO_TIMESTAMPNS_NEW: + return mptcp_setsockopt_sol_socket_int(msk, optname, optval, + optlen); + case SO_TIMESTAMPING_OLD: + case SO_TIMESTAMPING_NEW: + return mptcp_setsockopt_sol_socket_timestamping(msk, optname, + optval, optlen); + case SO_LINGER: + return mptcp_setsockopt_sol_socket_linger(msk, optval, optlen); + case SO_RCVLOWAT: + case SO_RCVTIMEO_OLD: + case SO_RCVTIMEO_NEW: + case SO_SNDTIMEO_OLD: + case SO_SNDTIMEO_NEW: + case SO_BUSY_POLL: + case SO_PREFER_BUSY_POLL: + case SO_BUSY_POLL_BUDGET: + /* No need to copy: only relevant for msk */ + return sock_setsockopt(sk->sk_socket, SOL_SOCKET, optname, optval, optlen); + case SO_NO_CHECK: + case SO_DONTROUTE: + case SO_BROADCAST: + case SO_BSDCOMPAT: + case SO_PASSCRED: + case SO_PASSSEC: + case SO_RXQ_OVFL: + case SO_WIFI_STATUS: + case SO_NOFCS: + case SO_SELECT_ERR_QUEUE: + return 0; + } + + /* SO_OOBINLINE is not supported, let's avoid the related mess + * SO_ATTACH_FILTER, SO_ATTACH_BPF, SO_ATTACH_REUSEPORT_CBPF, + * SO_DETACH_REUSEPORT_BPF, SO_DETACH_FILTER, SO_LOCK_FILTER, + * we must be careful with subflows + * + * SO_ATTACH_REUSEPORT_EBPF is not supported, at it checks + * explicitly the sk_protocol field + * + * SO_PEEK_OFF is unsupported, as it is for plain TCP + * SO_MAX_PACING_RATE is unsupported, we must be careful with subflows + * SO_CNX_ADVICE is currently unsupported, could possibly be relevant, + * but likely needs careful design + * + * SO_ZEROCOPY is currently unsupported, TODO in sndmsg + * SO_TXTIME is currently unsupported + */ + + return -EOPNOTSUPP; +} + +static int mptcp_setsockopt_v6(struct mptcp_sock *msk, int optname, + sockptr_t optval, unsigned int optlen) +{ + struct sock *sk = (struct sock *)msk; + int ret = -EOPNOTSUPP; + struct socket *ssock; + + switch (optname) { + case IPV6_V6ONLY: + case IPV6_TRANSPARENT: + case IPV6_FREEBIND: + lock_sock(sk); + ssock = __mptcp_nmpc_socket(msk); + if (!ssock) { + release_sock(sk); + return -EINVAL; + } + + ret = tcp_setsockopt(ssock->sk, SOL_IPV6, optname, optval, optlen); + if (ret != 0) { + release_sock(sk); + return ret; + } + + sockopt_seq_inc(msk); + + switch (optname) { + case IPV6_V6ONLY: + sk->sk_ipv6only = ssock->sk->sk_ipv6only; + break; + case IPV6_TRANSPARENT: + inet_sk(sk)->transparent = inet_sk(ssock->sk)->transparent; + break; + case IPV6_FREEBIND: + inet_sk(sk)->freebind = inet_sk(ssock->sk)->freebind; + break; + } + + release_sock(sk); + break; + } + + return ret; +} + +static bool mptcp_supported_sockopt(int level, int optname) +{ + if (level == SOL_IP) { + switch (optname) { + /* should work fine */ + case IP_FREEBIND: + case IP_TRANSPARENT: + + /* the following are control cmsg related */ + case IP_PKTINFO: + case IP_RECVTTL: + case IP_RECVTOS: + case IP_RECVOPTS: + case IP_RETOPTS: + case IP_PASSSEC: + case IP_RECVORIGDSTADDR: + case IP_CHECKSUM: + case IP_RECVFRAGSIZE: + + /* common stuff that need some love */ + case IP_TOS: + case IP_TTL: + case IP_BIND_ADDRESS_NO_PORT: + case IP_MTU_DISCOVER: + case IP_RECVERR: + + /* possibly less common may deserve some love */ + case IP_MINTTL: + + /* the following is apparently a no-op for plain TCP */ + case IP_RECVERR_RFC4884: + return true; + } + + /* IP_OPTIONS is not supported, needs subflow care */ + /* IP_HDRINCL, IP_NODEFRAG are not supported, RAW specific */ + /* IP_MULTICAST_TTL, IP_MULTICAST_LOOP, IP_UNICAST_IF, + * IP_ADD_MEMBERSHIP, IP_ADD_SOURCE_MEMBERSHIP, IP_DROP_MEMBERSHIP, + * IP_DROP_SOURCE_MEMBERSHIP, IP_BLOCK_SOURCE, IP_UNBLOCK_SOURCE, + * MCAST_JOIN_GROUP, MCAST_LEAVE_GROUP MCAST_JOIN_SOURCE_GROUP, + * MCAST_LEAVE_SOURCE_GROUP, MCAST_BLOCK_SOURCE, MCAST_UNBLOCK_SOURCE, + * MCAST_MSFILTER, IP_MULTICAST_ALL are not supported, better not deal + * with mcast stuff + */ + /* IP_IPSEC_POLICY, IP_XFRM_POLICY are nut supported, unrelated here */ + return false; + } + if (level == SOL_IPV6) { + switch (optname) { + case IPV6_V6ONLY: + + /* the following are control cmsg related */ + case IPV6_RECVPKTINFO: + case IPV6_2292PKTINFO: + case IPV6_RECVHOPLIMIT: + case IPV6_2292HOPLIMIT: + case IPV6_RECVRTHDR: + case IPV6_2292RTHDR: + case IPV6_RECVHOPOPTS: + case IPV6_2292HOPOPTS: + case IPV6_RECVDSTOPTS: + case IPV6_2292DSTOPTS: + case IPV6_RECVTCLASS: + case IPV6_FLOWINFO: + case IPV6_RECVPATHMTU: + case IPV6_RECVORIGDSTADDR: + case IPV6_RECVFRAGSIZE: + + /* the following ones need some love but are quite common */ + case IPV6_TCLASS: + case IPV6_TRANSPARENT: + case IPV6_FREEBIND: + case IPV6_PKTINFO: + case IPV6_2292PKTOPTIONS: + case IPV6_UNICAST_HOPS: + case IPV6_MTU_DISCOVER: + case IPV6_MTU: + case IPV6_RECVERR: + case IPV6_FLOWINFO_SEND: + case IPV6_FLOWLABEL_MGR: + case IPV6_MINHOPCOUNT: + case IPV6_DONTFRAG: + case IPV6_AUTOFLOWLABEL: + + /* the following one is a no-op for plain TCP */ + case IPV6_RECVERR_RFC4884: + return true; + } + + /* IPV6_HOPOPTS, IPV6_RTHDRDSTOPTS, IPV6_RTHDR, IPV6_DSTOPTS are + * not supported + */ + /* IPV6_MULTICAST_HOPS, IPV6_MULTICAST_LOOP, IPV6_UNICAST_IF, + * IPV6_MULTICAST_IF, IPV6_ADDRFORM, + * IPV6_ADD_MEMBERSHIP, IPV6_DROP_MEMBERSHIP, IPV6_JOIN_ANYCAST, + * IPV6_LEAVE_ANYCAST, IPV6_MULTICAST_ALL, MCAST_JOIN_GROUP, MCAST_LEAVE_GROUP, + * MCAST_JOIN_SOURCE_GROUP, MCAST_LEAVE_SOURCE_GROUP, + * MCAST_BLOCK_SOURCE, MCAST_UNBLOCK_SOURCE, MCAST_MSFILTER + * are not supported better not deal with mcast + */ + /* IPV6_ROUTER_ALERT, IPV6_ROUTER_ALERT_ISOLATE are not supported, since are evil */ + + /* IPV6_IPSEC_POLICY, IPV6_XFRM_POLICY are not supported */ + /* IPV6_ADDR_PREFERENCES is not supported, we must be careful with subflows */ + return false; + } + if (level == SOL_TCP) { + switch (optname) { + /* the following are no-op or should work just fine */ + case TCP_THIN_DUPACK: + case TCP_DEFER_ACCEPT: + + /* the following need some love */ + case TCP_MAXSEG: + case TCP_NODELAY: + case TCP_THIN_LINEAR_TIMEOUTS: + case TCP_CONGESTION: + case TCP_CORK: + case TCP_KEEPIDLE: + case TCP_KEEPINTVL: + case TCP_KEEPCNT: + case TCP_SYNCNT: + case TCP_SAVE_SYN: + case TCP_LINGER2: + case TCP_WINDOW_CLAMP: + case TCP_QUICKACK: + case TCP_USER_TIMEOUT: + case TCP_TIMESTAMP: + case TCP_NOTSENT_LOWAT: + case TCP_TX_DELAY: + case TCP_INQ: + case TCP_FASTOPEN_CONNECT: + return true; + } + + /* TCP_MD5SIG, TCP_MD5SIG_EXT are not supported, MD5 is not compatible with MPTCP */ + + /* TCP_REPAIR, TCP_REPAIR_QUEUE, TCP_QUEUE_SEQ, TCP_REPAIR_OPTIONS, + * TCP_REPAIR_WINDOW are not supported, better avoid this mess + */ + /* TCP_FASTOPEN_KEY, TCP_FASTOPEN, TCP_FASTOPEN_NO_COOKIE, + * are not supported fastopen is currently unsupported + */ + } + return false; +} + +static int mptcp_setsockopt_sol_tcp_congestion(struct mptcp_sock *msk, sockptr_t optval, + unsigned int optlen) +{ + struct mptcp_subflow_context *subflow; + struct sock *sk = (struct sock *)msk; + char name[TCP_CA_NAME_MAX]; + bool cap_net_admin; + int ret; + + if (optlen < 1) + return -EINVAL; + + ret = strncpy_from_sockptr(name, optval, + min_t(long, TCP_CA_NAME_MAX - 1, optlen)); + if (ret < 0) + return -EFAULT; + + name[ret] = 0; + + cap_net_admin = ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN); + + ret = 0; + lock_sock(sk); + sockopt_seq_inc(msk); + mptcp_for_each_subflow(msk, subflow) { + struct sock *ssk = mptcp_subflow_tcp_sock(subflow); + int err; + + lock_sock(ssk); + err = tcp_set_congestion_control(ssk, name, true, cap_net_admin); + if (err < 0 && ret == 0) + ret = err; + subflow->setsockopt_seq = msk->setsockopt_seq; + release_sock(ssk); + } + + if (ret == 0) + strcpy(msk->ca_name, name); + + release_sock(sk); + return ret; +} + +static int mptcp_setsockopt_sol_tcp_cork(struct mptcp_sock *msk, sockptr_t optval, + unsigned int optlen) +{ + struct mptcp_subflow_context *subflow; + struct sock *sk = (struct sock *)msk; + int val; + + if (optlen < sizeof(int)) + return -EINVAL; + + if (copy_from_sockptr(&val, optval, sizeof(val))) + return -EFAULT; + + lock_sock(sk); + sockopt_seq_inc(msk); + msk->cork = !!val; + mptcp_for_each_subflow(msk, subflow) { + struct sock *ssk = mptcp_subflow_tcp_sock(subflow); + + lock_sock(ssk); + __tcp_sock_set_cork(ssk, !!val); + release_sock(ssk); + } + if (!val) + mptcp_check_and_set_pending(sk); + release_sock(sk); + + return 0; +} + +static int mptcp_setsockopt_sol_tcp_nodelay(struct mptcp_sock *msk, sockptr_t optval, + unsigned int optlen) +{ + struct mptcp_subflow_context *subflow; + struct sock *sk = (struct sock *)msk; + int val; + + if (optlen < sizeof(int)) + return -EINVAL; + + if (copy_from_sockptr(&val, optval, sizeof(val))) + return -EFAULT; + + lock_sock(sk); + sockopt_seq_inc(msk); + msk->nodelay = !!val; + mptcp_for_each_subflow(msk, subflow) { + struct sock *ssk = mptcp_subflow_tcp_sock(subflow); + + lock_sock(ssk); + __tcp_sock_set_nodelay(ssk, !!val); + release_sock(ssk); + } + if (val) + mptcp_check_and_set_pending(sk); + release_sock(sk); + + return 0; +} + +static int mptcp_setsockopt_sol_ip_set_transparent(struct mptcp_sock *msk, int optname, + sockptr_t optval, unsigned int optlen) +{ + struct sock *sk = (struct sock *)msk; + struct inet_sock *issk; + struct socket *ssock; + int err; + + err = ip_setsockopt(sk, SOL_IP, optname, optval, optlen); + if (err != 0) + return err; + + lock_sock(sk); + + ssock = __mptcp_nmpc_socket(msk); + if (!ssock) { + release_sock(sk); + return -EINVAL; + } + + issk = inet_sk(ssock->sk); + + switch (optname) { + case IP_FREEBIND: + issk->freebind = inet_sk(sk)->freebind; + break; + case IP_TRANSPARENT: + issk->transparent = inet_sk(sk)->transparent; + break; + default: + release_sock(sk); + WARN_ON_ONCE(1); + return -EOPNOTSUPP; + } + + sockopt_seq_inc(msk); + release_sock(sk); + return 0; +} + +static int mptcp_setsockopt_v4_set_tos(struct mptcp_sock *msk, int optname, + sockptr_t optval, unsigned int optlen) +{ + struct mptcp_subflow_context *subflow; + struct sock *sk = (struct sock *)msk; + int err, val; + + err = ip_setsockopt(sk, SOL_IP, optname, optval, optlen); + + if (err != 0) + return err; + + lock_sock(sk); + sockopt_seq_inc(msk); + val = inet_sk(sk)->tos; + mptcp_for_each_subflow(msk, subflow) { + struct sock *ssk = mptcp_subflow_tcp_sock(subflow); + bool slow; + + slow = lock_sock_fast(ssk); + __ip_sock_set_tos(ssk, val); + unlock_sock_fast(ssk, slow); + } + release_sock(sk); + + return err; +} + +static int mptcp_setsockopt_v4(struct mptcp_sock *msk, int optname, + sockptr_t optval, unsigned int optlen) +{ + switch (optname) { + case IP_FREEBIND: + case IP_TRANSPARENT: + return mptcp_setsockopt_sol_ip_set_transparent(msk, optname, optval, optlen); + case IP_TOS: + return mptcp_setsockopt_v4_set_tos(msk, optname, optval, optlen); + } + + return -EOPNOTSUPP; +} + +static int mptcp_setsockopt_sol_tcp_defer(struct mptcp_sock *msk, sockptr_t optval, + unsigned int optlen) +{ + struct socket *listener; + + listener = __mptcp_nmpc_socket(msk); + if (!listener) + return 0; /* TCP_DEFER_ACCEPT does not fail */ + + return tcp_setsockopt(listener->sk, SOL_TCP, TCP_DEFER_ACCEPT, optval, optlen); +} + +static int mptcp_setsockopt_first_sf_only(struct mptcp_sock *msk, int level, int optname, + sockptr_t optval, unsigned int optlen) +{ + struct sock *sk = (struct sock *)msk; + struct socket *sock; + int ret = -EINVAL; + + /* Limit to first subflow, before the connection establishment */ + lock_sock(sk); + sock = __mptcp_nmpc_socket(msk); + if (!sock) + goto unlock; + + ret = tcp_setsockopt(sock->sk, level, optname, optval, optlen); + +unlock: + release_sock(sk); + return ret; +} + +static int mptcp_setsockopt_sol_tcp(struct mptcp_sock *msk, int optname, + sockptr_t optval, unsigned int optlen) +{ + struct sock *sk = (void *)msk; + int ret, val; + + switch (optname) { + case TCP_INQ: + ret = mptcp_get_int_option(msk, optval, optlen, &val); + if (ret) + return ret; + if (val < 0 || val > 1) + return -EINVAL; + + lock_sock(sk); + msk->recvmsg_inq = !!val; + release_sock(sk); + return 0; + case TCP_ULP: + return -EOPNOTSUPP; + case TCP_CONGESTION: + return mptcp_setsockopt_sol_tcp_congestion(msk, optval, optlen); + case TCP_CORK: + return mptcp_setsockopt_sol_tcp_cork(msk, optval, optlen); + case TCP_NODELAY: + return mptcp_setsockopt_sol_tcp_nodelay(msk, optval, optlen); + case TCP_DEFER_ACCEPT: + return mptcp_setsockopt_sol_tcp_defer(msk, optval, optlen); + case TCP_FASTOPEN_CONNECT: + return mptcp_setsockopt_first_sf_only(msk, SOL_TCP, optname, + optval, optlen); + } + + return -EOPNOTSUPP; +} + +int mptcp_setsockopt(struct sock *sk, int level, int optname, + sockptr_t optval, unsigned int optlen) +{ + struct mptcp_sock *msk = mptcp_sk(sk); + struct sock *ssk; + + pr_debug("msk=%p", msk); + + if (level == SOL_SOCKET) + return mptcp_setsockopt_sol_socket(msk, optname, optval, optlen); + + if (!mptcp_supported_sockopt(level, optname)) + return -ENOPROTOOPT; + + /* @@ the meaning of setsockopt() when the socket is connected and + * there are multiple subflows is not yet defined. It is up to the + * MPTCP-level socket to configure the subflows until the subflow + * is in TCP fallback, when TCP socket options are passed through + * to the one remaining subflow. + */ + lock_sock(sk); + ssk = __mptcp_tcp_fallback(msk); + release_sock(sk); + if (ssk) + return tcp_setsockopt(ssk, level, optname, optval, optlen); + + if (level == SOL_IP) + return mptcp_setsockopt_v4(msk, optname, optval, optlen); + + if (level == SOL_IPV6) + return mptcp_setsockopt_v6(msk, optname, optval, optlen); + + if (level == SOL_TCP) + return mptcp_setsockopt_sol_tcp(msk, optname, optval, optlen); + + return -EOPNOTSUPP; +} + +static int mptcp_getsockopt_first_sf_only(struct mptcp_sock *msk, int level, int optname, + char __user *optval, int __user *optlen) +{ + struct sock *sk = (struct sock *)msk; + struct socket *ssock; + int ret = -EINVAL; + struct sock *ssk; + + lock_sock(sk); + ssk = msk->first; + if (ssk) { + ret = tcp_getsockopt(ssk, level, optname, optval, optlen); + goto out; + } + + ssock = __mptcp_nmpc_socket(msk); + if (!ssock) + goto out; + + ret = tcp_getsockopt(ssock->sk, level, optname, optval, optlen); + +out: + release_sock(sk); + return ret; +} + +void mptcp_diag_fill_info(struct mptcp_sock *msk, struct mptcp_info *info) +{ + u32 flags = 0; + u8 val; + + memset(info, 0, sizeof(*info)); + + info->mptcpi_subflows = READ_ONCE(msk->pm.subflows); + info->mptcpi_add_addr_signal = READ_ONCE(msk->pm.add_addr_signaled); + info->mptcpi_add_addr_accepted = READ_ONCE(msk->pm.add_addr_accepted); + info->mptcpi_local_addr_used = READ_ONCE(msk->pm.local_addr_used); + info->mptcpi_subflows_max = mptcp_pm_get_subflows_max(msk); + val = mptcp_pm_get_add_addr_signal_max(msk); + info->mptcpi_add_addr_signal_max = val; + val = mptcp_pm_get_add_addr_accept_max(msk); + info->mptcpi_add_addr_accepted_max = val; + info->mptcpi_local_addr_max = mptcp_pm_get_local_addr_max(msk); + if (test_bit(MPTCP_FALLBACK_DONE, &msk->flags)) + flags |= MPTCP_INFO_FLAG_FALLBACK; + if (READ_ONCE(msk->can_ack)) + flags |= MPTCP_INFO_FLAG_REMOTE_KEY_RECEIVED; + info->mptcpi_flags = flags; + info->mptcpi_token = READ_ONCE(msk->token); + info->mptcpi_write_seq = READ_ONCE(msk->write_seq); + info->mptcpi_snd_una = READ_ONCE(msk->snd_una); + info->mptcpi_rcv_nxt = READ_ONCE(msk->ack_seq); + info->mptcpi_csum_enabled = READ_ONCE(msk->csum_enabled); +} +EXPORT_SYMBOL_GPL(mptcp_diag_fill_info); + +static int mptcp_getsockopt_info(struct mptcp_sock *msk, char __user *optval, int __user *optlen) +{ + struct mptcp_info m_info; + int len; + + if (get_user(len, optlen)) + return -EFAULT; + + len = min_t(unsigned int, len, sizeof(struct mptcp_info)); + + mptcp_diag_fill_info(msk, &m_info); + + if (put_user(len, optlen)) + return -EFAULT; + + if (copy_to_user(optval, &m_info, len)) + return -EFAULT; + + return 0; +} + +static int mptcp_put_subflow_data(struct mptcp_subflow_data *sfd, + char __user *optval, + u32 copied, + int __user *optlen) +{ + u32 copylen = min_t(u32, sfd->size_subflow_data, sizeof(*sfd)); + + if (copied) + copied += sfd->size_subflow_data; + else + copied = copylen; + + if (put_user(copied, optlen)) + return -EFAULT; + + if (copy_to_user(optval, sfd, copylen)) + return -EFAULT; + + return 0; +} + +static int mptcp_get_subflow_data(struct mptcp_subflow_data *sfd, + char __user *optval, int __user *optlen) +{ + int len, copylen; + + if (get_user(len, optlen)) + return -EFAULT; + + /* if mptcp_subflow_data size is changed, need to adjust + * this function to deal with programs using old version. + */ + BUILD_BUG_ON(sizeof(*sfd) != MIN_INFO_OPTLEN_SIZE); + + if (len < MIN_INFO_OPTLEN_SIZE) + return -EINVAL; + + memset(sfd, 0, sizeof(*sfd)); + + copylen = min_t(unsigned int, len, sizeof(*sfd)); + if (copy_from_user(sfd, optval, copylen)) + return -EFAULT; + + /* size_subflow_data is u32, but len is signed */ + if (sfd->size_subflow_data > INT_MAX || + sfd->size_user > INT_MAX) + return -EINVAL; + + if (sfd->size_subflow_data < MIN_INFO_OPTLEN_SIZE || + sfd->size_subflow_data > len) + return -EINVAL; + + if (sfd->num_subflows || sfd->size_kernel) + return -EINVAL; + + return len - sfd->size_subflow_data; +} + +static int mptcp_getsockopt_tcpinfo(struct mptcp_sock *msk, char __user *optval, + int __user *optlen) +{ + struct mptcp_subflow_context *subflow; + struct sock *sk = &msk->sk.icsk_inet.sk; + unsigned int sfcount = 0, copied = 0; + struct mptcp_subflow_data sfd; + char __user *infoptr; + int len; + + len = mptcp_get_subflow_data(&sfd, optval, optlen); + if (len < 0) + return len; + + sfd.size_kernel = sizeof(struct tcp_info); + sfd.size_user = min_t(unsigned int, sfd.size_user, + sizeof(struct tcp_info)); + + infoptr = optval + sfd.size_subflow_data; + + lock_sock(sk); + + mptcp_for_each_subflow(msk, subflow) { + struct sock *ssk = mptcp_subflow_tcp_sock(subflow); + + ++sfcount; + + if (len && len >= sfd.size_user) { + struct tcp_info info; + + tcp_get_info(ssk, &info); + + if (copy_to_user(infoptr, &info, sfd.size_user)) { + release_sock(sk); + return -EFAULT; + } + + infoptr += sfd.size_user; + copied += sfd.size_user; + len -= sfd.size_user; + } + } + + release_sock(sk); + + sfd.num_subflows = sfcount; + + if (mptcp_put_subflow_data(&sfd, optval, copied, optlen)) + return -EFAULT; + + return 0; +} + +static void mptcp_get_sub_addrs(const struct sock *sk, struct mptcp_subflow_addrs *a) +{ + struct inet_sock *inet = inet_sk(sk); + + memset(a, 0, sizeof(*a)); + + if (sk->sk_family == AF_INET) { + a->sin_local.sin_family = AF_INET; + a->sin_local.sin_port = inet->inet_sport; + a->sin_local.sin_addr.s_addr = inet->inet_rcv_saddr; + + if (!a->sin_local.sin_addr.s_addr) + a->sin_local.sin_addr.s_addr = inet->inet_saddr; + + a->sin_remote.sin_family = AF_INET; + a->sin_remote.sin_port = inet->inet_dport; + a->sin_remote.sin_addr.s_addr = inet->inet_daddr; +#if IS_ENABLED(CONFIG_IPV6) + } else if (sk->sk_family == AF_INET6) { + const struct ipv6_pinfo *np = inet6_sk(sk); + + if (WARN_ON_ONCE(!np)) + return; + + a->sin6_local.sin6_family = AF_INET6; + a->sin6_local.sin6_port = inet->inet_sport; + + if (ipv6_addr_any(&sk->sk_v6_rcv_saddr)) + a->sin6_local.sin6_addr = np->saddr; + else + a->sin6_local.sin6_addr = sk->sk_v6_rcv_saddr; + + a->sin6_remote.sin6_family = AF_INET6; + a->sin6_remote.sin6_port = inet->inet_dport; + a->sin6_remote.sin6_addr = sk->sk_v6_daddr; +#endif + } +} + +static int mptcp_getsockopt_subflow_addrs(struct mptcp_sock *msk, char __user *optval, + int __user *optlen) +{ + struct sock *sk = &msk->sk.icsk_inet.sk; + struct mptcp_subflow_context *subflow; + unsigned int sfcount = 0, copied = 0; + struct mptcp_subflow_data sfd; + char __user *addrptr; + int len; + + len = mptcp_get_subflow_data(&sfd, optval, optlen); + if (len < 0) + return len; + + sfd.size_kernel = sizeof(struct mptcp_subflow_addrs); + sfd.size_user = min_t(unsigned int, sfd.size_user, + sizeof(struct mptcp_subflow_addrs)); + + addrptr = optval + sfd.size_subflow_data; + + lock_sock(sk); + + mptcp_for_each_subflow(msk, subflow) { + struct sock *ssk = mptcp_subflow_tcp_sock(subflow); + + ++sfcount; + + if (len && len >= sfd.size_user) { + struct mptcp_subflow_addrs a; + + mptcp_get_sub_addrs(ssk, &a); + + if (copy_to_user(addrptr, &a, sfd.size_user)) { + release_sock(sk); + return -EFAULT; + } + + addrptr += sfd.size_user; + copied += sfd.size_user; + len -= sfd.size_user; + } + } + + release_sock(sk); + + sfd.num_subflows = sfcount; + + if (mptcp_put_subflow_data(&sfd, optval, copied, optlen)) + return -EFAULT; + + return 0; +} + +static int mptcp_put_int_option(struct mptcp_sock *msk, char __user *optval, + int __user *optlen, int val) +{ + int len; + + if (get_user(len, optlen)) + return -EFAULT; + if (len < 0) + return -EINVAL; + + if (len < sizeof(int) && len > 0 && val >= 0 && val <= 255) { + unsigned char ucval = (unsigned char)val; + + len = 1; + if (put_user(len, optlen)) + return -EFAULT; + if (copy_to_user(optval, &ucval, 1)) + return -EFAULT; + } else { + len = min_t(unsigned int, len, sizeof(int)); + if (put_user(len, optlen)) + return -EFAULT; + if (copy_to_user(optval, &val, len)) + return -EFAULT; + } + + return 0; +} + +static int mptcp_getsockopt_sol_tcp(struct mptcp_sock *msk, int optname, + char __user *optval, int __user *optlen) +{ + switch (optname) { + case TCP_ULP: + case TCP_CONGESTION: + case TCP_INFO: + case TCP_CC_INFO: + case TCP_DEFER_ACCEPT: + case TCP_FASTOPEN_CONNECT: + return mptcp_getsockopt_first_sf_only(msk, SOL_TCP, optname, + optval, optlen); + case TCP_INQ: + return mptcp_put_int_option(msk, optval, optlen, msk->recvmsg_inq); + case TCP_CORK: + return mptcp_put_int_option(msk, optval, optlen, msk->cork); + case TCP_NODELAY: + return mptcp_put_int_option(msk, optval, optlen, msk->nodelay); + } + return -EOPNOTSUPP; +} + +static int mptcp_getsockopt_v4(struct mptcp_sock *msk, int optname, + char __user *optval, int __user *optlen) +{ + struct sock *sk = (void *)msk; + + switch (optname) { + case IP_TOS: + return mptcp_put_int_option(msk, optval, optlen, inet_sk(sk)->tos); + } + + return -EOPNOTSUPP; +} + +static int mptcp_getsockopt_sol_mptcp(struct mptcp_sock *msk, int optname, + char __user *optval, int __user *optlen) +{ + switch (optname) { + case MPTCP_INFO: + return mptcp_getsockopt_info(msk, optval, optlen); + case MPTCP_TCPINFO: + return mptcp_getsockopt_tcpinfo(msk, optval, optlen); + case MPTCP_SUBFLOW_ADDRS: + return mptcp_getsockopt_subflow_addrs(msk, optval, optlen); + } + + return -EOPNOTSUPP; +} + +int mptcp_getsockopt(struct sock *sk, int level, int optname, + char __user *optval, int __user *option) +{ + struct mptcp_sock *msk = mptcp_sk(sk); + struct sock *ssk; + + pr_debug("msk=%p", msk); + + /* @@ the meaning of setsockopt() when the socket is connected and + * there are multiple subflows is not yet defined. It is up to the + * MPTCP-level socket to configure the subflows until the subflow + * is in TCP fallback, when socket options are passed through + * to the one remaining subflow. + */ + lock_sock(sk); + ssk = __mptcp_tcp_fallback(msk); + release_sock(sk); + if (ssk) + return tcp_getsockopt(ssk, level, optname, optval, option); + + if (level == SOL_IP) + return mptcp_getsockopt_v4(msk, optname, optval, option); + if (level == SOL_TCP) + return mptcp_getsockopt_sol_tcp(msk, optname, optval, option); + if (level == SOL_MPTCP) + return mptcp_getsockopt_sol_mptcp(msk, optname, optval, option); + return -EOPNOTSUPP; +} + +static void sync_socket_options(struct mptcp_sock *msk, struct sock *ssk) +{ + static const unsigned int tx_rx_locks = SOCK_RCVBUF_LOCK | SOCK_SNDBUF_LOCK; + struct sock *sk = (struct sock *)msk; + + if (ssk->sk_prot->keepalive) { + if (sock_flag(sk, SOCK_KEEPOPEN)) + ssk->sk_prot->keepalive(ssk, 1); + else + ssk->sk_prot->keepalive(ssk, 0); + } + + ssk->sk_priority = sk->sk_priority; + ssk->sk_bound_dev_if = sk->sk_bound_dev_if; + ssk->sk_incoming_cpu = sk->sk_incoming_cpu; + __ip_sock_set_tos(ssk, inet_sk(sk)->tos); + + if (sk->sk_userlocks & tx_rx_locks) { + ssk->sk_userlocks |= sk->sk_userlocks & tx_rx_locks; + if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) + WRITE_ONCE(ssk->sk_sndbuf, sk->sk_sndbuf); + if (sk->sk_userlocks & SOCK_RCVBUF_LOCK) + WRITE_ONCE(ssk->sk_rcvbuf, sk->sk_rcvbuf); + } + + if (sock_flag(sk, SOCK_LINGER)) { + ssk->sk_lingertime = sk->sk_lingertime; + sock_set_flag(ssk, SOCK_LINGER); + } else { + sock_reset_flag(ssk, SOCK_LINGER); + } + + if (sk->sk_mark != ssk->sk_mark) { + ssk->sk_mark = sk->sk_mark; + sk_dst_reset(ssk); + } + + sock_valbool_flag(ssk, SOCK_DBG, sock_flag(sk, SOCK_DBG)); + + if (inet_csk(sk)->icsk_ca_ops != inet_csk(ssk)->icsk_ca_ops) + tcp_set_congestion_control(ssk, msk->ca_name, false, true); + __tcp_sock_set_cork(ssk, !!msk->cork); + __tcp_sock_set_nodelay(ssk, !!msk->nodelay); + + inet_sk(ssk)->transparent = inet_sk(sk)->transparent; + inet_sk(ssk)->freebind = inet_sk(sk)->freebind; +} + +static void __mptcp_sockopt_sync(struct mptcp_sock *msk, struct sock *ssk) +{ + bool slow = lock_sock_fast(ssk); + + sync_socket_options(msk, ssk); + + unlock_sock_fast(ssk, slow); +} + +void mptcp_sockopt_sync(struct mptcp_sock *msk, struct sock *ssk) +{ + struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); + + msk_owned_by_me(msk); + + if (READ_ONCE(subflow->setsockopt_seq) != msk->setsockopt_seq) { + __mptcp_sockopt_sync(msk, ssk); + + subflow->setsockopt_seq = msk->setsockopt_seq; + } +} + +void mptcp_sockopt_sync_locked(struct mptcp_sock *msk, struct sock *ssk) +{ + struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); + + msk_owned_by_me(msk); + + if (READ_ONCE(subflow->setsockopt_seq) != msk->setsockopt_seq) { + sync_socket_options(msk, ssk); + + subflow->setsockopt_seq = msk->setsockopt_seq; + } +} |