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af_inet.c
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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* INET An implementation of the TCP/IP protocol suite for the LINUX
* operating system. INET is implemented using the BSD Socket
* interface as the means of communication with the user level.
*
* PF_INET protocol family socket handler.
*
* Authors: Ross Biro
* Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
* Florian La Roche, <flla@stud.uni-sb.de>
* Alan Cox, <A.Cox@swansea.ac.uk>
*
* Changes (see also sock.c)
*
* piggy,
* Karl Knutson : Socket protocol table
* A.N.Kuznetsov : Socket death error in accept().
* John Richardson : Fix non blocking error in connect()
* so sockets that fail to connect
* don't return -EINPROGRESS.
* Alan Cox : Asynchronous I/O support
* Alan Cox : Keep correct socket pointer on sock
* structures
* when accept() ed
* Alan Cox : Semantics of SO_LINGER aren't state
* moved to close when you look carefully.
* With this fixed and the accept bug fixed
* some RPC stuff seems happier.
* Niibe Yutaka : 4.4BSD style write async I/O
* Alan Cox,
* Tony Gale : Fixed reuse semantics.
* Alan Cox : bind() shouldn't abort existing but dead
* sockets. Stops FTP netin:.. I hope.
* Alan Cox : bind() works correctly for RAW sockets.
* Note that FreeBSD at least was broken
* in this respect so be careful with
* compatibility tests...
* Alan Cox : routing cache support
* Alan Cox : memzero the socket structure for
* compactness.
* Matt Day : nonblock connect error handler
* Alan Cox : Allow large numbers of pending sockets
* (eg for big web sites), but only if
* specifically application requested.
* Alan Cox : New buffering throughout IP. Used
* dumbly.
* Alan Cox : New buffering now used smartly.
* Alan Cox : BSD rather than common sense
* interpretation of listen.
* Germano Caronni : Assorted small races.
* Alan Cox : sendmsg/recvmsg basic support.
* Alan Cox : Only sendmsg/recvmsg now supported.
* Alan Cox : Locked down bind (see security list).
* Alan Cox : Loosened bind a little.
* Mike McLagan : ADD/DEL DLCI Ioctls
* Willy Konynenberg : Transparent proxying support.
* David S. Miller : New socket lookup architecture.
* Some other random speedups.
* Cyrus Durgin : Cleaned up file for kmod hacks.
* Andi Kleen : Fix inet_stream_connect TCP race.
*/
#define pr_fmt(fmt) "IPv4: " fmt
#include <linux/err.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/kernel.h>
#include <linux/kmod.h>
#include <linux/sched.h>
#include <linux/timer.h>
#include <linux/string.h>
#include <linux/sockios.h>
#include <linux/net.h>
#include <linux/capability.h>
#include <linux/fcntl.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/stat.h>
#include <linux/init.h>
#include <linux/poll.h>
#include <linux/netfilter_ipv4.h>
#include <linux/random.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <linux/inet.h>
#include <linux/igmp.h>
#include <linux/inetdevice.h>
#include <linux/netdevice.h>
#include <net/checksum.h>
#include <net/ip.h>
#include <net/protocol.h>
#include <net/arp.h>
#include <net/route.h>
#include <net/ip_fib.h>
#include <net/inet_connection_sock.h>
#include <net/gro.h>
#include <net/tcp.h>
#include <net/udp.h>
#include <net/udplite.h>
#include <net/ping.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <net/raw.h>
#include <net/icmp.h>
#include <net/inet_common.h>
#include <net/ip_tunnels.h>
#include <net/xfrm.h>
#include <net/net_namespace.h>
#include <net/secure_seq.h>
#ifdef CONFIG_IP_MROUTE
#include <linux/mroute.h>
#endif
#include <net/l3mdev.h>
#include <net/compat.h>
#include <trace/events/sock.h>
/* The inetsw table contains everything that inet_create needs to
* build a new socket.
*/
static struct list_head inetsw[SOCK_MAX];
static DEFINE_SPINLOCK(inetsw_lock);
/* New destruction routine */
void inet_sock_destruct(struct sock *sk)
{
struct inet_sock *inet = inet_sk(sk);
__skb_queue_purge(&sk->sk_receive_queue);
__skb_queue_purge(&sk->sk_error_queue);
sk_mem_reclaim_final(sk);
if (sk->sk_type == SOCK_STREAM && sk->sk_state != TCP_CLOSE) {
pr_err("Attempt to release TCP socket in state %d %p\n",
sk->sk_state, sk);
return;
}
if (!sock_flag(sk, SOCK_DEAD)) {
pr_err("Attempt to release alive inet socket %p\n", sk);
return;
}
WARN_ON_ONCE(atomic_read(&sk->sk_rmem_alloc));
WARN_ON_ONCE(refcount_read(&sk->sk_wmem_alloc));
WARN_ON_ONCE(sk->sk_wmem_queued);
WARN_ON_ONCE(sk_forward_alloc_get(sk));
kfree(rcu_dereference_protected(inet->inet_opt, 1));
dst_release(rcu_dereference_protected(sk->sk_dst_cache, 1));
dst_release(rcu_dereference_protected(sk->sk_rx_dst, 1));
}
EXPORT_SYMBOL(inet_sock_destruct);
/*
* The routines beyond this point handle the behaviour of an AF_INET
* socket object. Mostly it punts to the subprotocols of IP to do
* the work.
*/
/*
* Automatically bind an unbound socket.
*/
static int inet_autobind(struct sock *sk)
{
struct inet_sock *inet;
/* We may need to bind the socket. */
lock_sock(sk);
inet = inet_sk(sk);
if (!inet->inet_num) {
if (sk->sk_prot->get_port(sk, 0)) {
release_sock(sk);
return -EAGAIN;
}
inet->inet_sport = htons(inet->inet_num);
}
release_sock(sk);
return 0;
}
/*
* Move a socket into listening state.
*/
int inet_listen(struct socket *sock, int backlog)
{
struct sock *sk = sock->sk;
unsigned char old_state;
int err, tcp_fastopen;
lock_sock(sk);
err = -EINVAL;
if (sock->state != SS_UNCONNECTED || sock->type != SOCK_STREAM)
goto out;
old_state = sk->sk_state;
if (!((1 << old_state) & (TCPF_CLOSE | TCPF_LISTEN)))
goto out;
WRITE_ONCE(sk->sk_max_ack_backlog, backlog);
/* Really, if the socket is already in listen state
* we can only allow the backlog to be adjusted.
*/
if (old_state != TCP_LISTEN) {
/* Enable TFO w/o requiring TCP_FASTOPEN socket option.
* Note that only TCP sockets (SOCK_STREAM) will reach here.
* Also fastopen backlog may already been set via the option
* because the socket was in TCP_LISTEN state previously but
* was shutdown() rather than close().
*/
tcp_fastopen = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_fastopen);
if ((tcp_fastopen & TFO_SERVER_WO_SOCKOPT1) &&
(tcp_fastopen & TFO_SERVER_ENABLE) &&
!inet_csk(sk)->icsk_accept_queue.fastopenq.max_qlen) {
fastopen_queue_tune(sk, backlog);
tcp_fastopen_init_key_once(sock_net(sk));
}
err = inet_csk_listen_start(sk);
if (err)
goto out;
tcp_call_bpf(sk, BPF_SOCK_OPS_TCP_LISTEN_CB, 0, NULL);
}
err = 0;
out:
release_sock(sk);
return err;
}
EXPORT_SYMBOL(inet_listen);
/*
* Create an inet socket.
*/
static int inet_create(struct net *net, struct socket *sock, int protocol,
int kern)
{
struct sock *sk;
struct inet_protosw *answer;
struct inet_sock *inet;
struct proto *answer_prot;
unsigned char answer_flags;
int try_loading_module = 0;
int err;
if (protocol < 0 || protocol >= IPPROTO_MAX)
return -EINVAL;
sock->state = SS_UNCONNECTED;
/* Look for the requested type/protocol pair. */
lookup_protocol:
err = -ESOCKTNOSUPPORT;
rcu_read_lock();
list_for_each_entry_rcu(answer, &inetsw[sock->type], list) {
err = 0;
/* Check the non-wild match. */
if (protocol == answer->protocol) {
if (protocol != IPPROTO_IP)
break;
} else {
/* Check for the two wild cases. */
if (IPPROTO_IP == protocol) {
protocol = answer->protocol;
break;
}
if (IPPROTO_IP == answer->protocol)
break;
}
err = -EPROTONOSUPPORT;
}
if (unlikely(err)) {
if (try_loading_module < 2) {
rcu_read_unlock();
/*
* Be more specific, e.g. net-pf-2-proto-132-type-1
* (net-pf-PF_INET-proto-IPPROTO_SCTP-type-SOCK_STREAM)
*/
if (++try_loading_module == 1)
request_module("net-pf-%d-proto-%d-type-%d",
PF_INET, protocol, sock->type);
/*
* Fall back to generic, e.g. net-pf-2-proto-132
* (net-pf-PF_INET-proto-IPPROTO_SCTP)
*/
else
request_module("net-pf-%d-proto-%d",
PF_INET, protocol);
goto lookup_protocol;
} else
goto out_rcu_unlock;
}
err = -EPERM;
if (sock->type == SOCK_RAW && !kern &&
!ns_capable(net->user_ns, CAP_NET_RAW))
goto out_rcu_unlock;
sock->ops = answer->ops;
answer_prot = answer->prot;
answer_flags = answer->flags;
rcu_read_unlock();
WARN_ON(!answer_prot->slab);
err = -ENOMEM;
sk = sk_alloc(net, PF_INET, GFP_KERNEL, answer_prot, kern);
if (!sk)
goto out;
err = 0;
if (INET_PROTOSW_REUSE & answer_flags)
sk->sk_reuse = SK_CAN_REUSE;
inet = inet_sk(sk);
inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
inet->nodefrag = 0;
if (SOCK_RAW == sock->type) {
inet->inet_num = protocol;
if (IPPROTO_RAW == protocol)
inet->hdrincl = 1;
}
if (READ_ONCE(net->ipv4.sysctl_ip_no_pmtu_disc))
inet->pmtudisc = IP_PMTUDISC_DONT;
else
inet->pmtudisc = IP_PMTUDISC_WANT;
inet->inet_id = 0;
sock_init_data(sock, sk);
sk->sk_destruct = inet_sock_destruct;
sk->sk_protocol = protocol;
sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
sk->sk_txrehash = READ_ONCE(net->core.sysctl_txrehash);
inet->uc_ttl = -1;
inet->mc_loop = 1;
inet->mc_ttl = 1;
inet->mc_all = 1;
inet->mc_index = 0;
inet->mc_list = NULL;
inet->rcv_tos = 0;
if (inet->inet_num) {
/* It assumes that any protocol which allows
* the user to assign a number at socket
* creation time automatically
* shares.
*/
inet->inet_sport = htons(inet->inet_num);
/* Add to protocol hash chains. */
err = sk->sk_prot->hash(sk);
if (err) {
sk_common_release(sk);
goto out;
}
}
if (sk->sk_prot->init) {
err = sk->sk_prot->init(sk);
if (err) {
sk_common_release(sk);
goto out;
}
}
if (!kern) {
err = BPF_CGROUP_RUN_PROG_INET_SOCK(sk);
if (err) {
sk_common_release(sk);
goto out;
}
}
out:
return err;
out_rcu_unlock:
rcu_read_unlock();
goto out;
}
/*
* The peer socket should always be NULL (or else). When we call this
* function we are destroying the object and from then on nobody
* should refer to it.
*/
int inet_release(struct socket *sock)
{
struct sock *sk = sock->sk;
if (sk) {
long timeout;
if (!sk->sk_kern_sock)
BPF_CGROUP_RUN_PROG_INET_SOCK_RELEASE(sk);
/* Applications forget to leave groups before exiting */
ip_mc_drop_socket(sk);
/* If linger is set, we don't return until the close
* is complete. Otherwise we return immediately. The
* actually closing is done the same either way.
*
* If the close is due to the process exiting, we never
* linger..
*/
timeout = 0;
if (sock_flag(sk, SOCK_LINGER) &&
!(current->flags & PF_EXITING))
timeout = sk->sk_lingertime;
sk->sk_prot->close(sk, timeout);
sock->sk = NULL;
}
return 0;
}
EXPORT_SYMBOL(inet_release);
int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
{
struct sock *sk = sock->sk;
u32 flags = BIND_WITH_LOCK;
int err;
/* If the socket has its own bind function then use it. (RAW) */
if (sk->sk_prot->bind) {
return sk->sk_prot->bind(sk, uaddr, addr_len);
}
if (addr_len < sizeof(struct sockaddr_in))
return -EINVAL;
/* BPF prog is run before any checks are done so that if the prog
* changes context in a wrong way it will be caught.
*/
err = BPF_CGROUP_RUN_PROG_INET_BIND_LOCK(sk, uaddr,
CGROUP_INET4_BIND, &flags);
if (err)
return err;
return __inet_bind(sk, uaddr, addr_len, flags);
}
EXPORT_SYMBOL(inet_bind);
int __inet_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len,
u32 flags)
{
struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
struct inet_sock *inet = inet_sk(sk);
struct net *net = sock_net(sk);
unsigned short snum;
int chk_addr_ret;
u32 tb_id = RT_TABLE_LOCAL;
int err;
if (addr->sin_family != AF_INET) {
/* Compatibility games : accept AF_UNSPEC (mapped to AF_INET)
* only if s_addr is INADDR_ANY.
*/
err = -EAFNOSUPPORT;
if (addr->sin_family != AF_UNSPEC ||
addr->sin_addr.s_addr != htonl(INADDR_ANY))
goto out;
}
tb_id = l3mdev_fib_table_by_index(net, sk->sk_bound_dev_if) ? : tb_id;
chk_addr_ret = inet_addr_type_table(net, addr->sin_addr.s_addr, tb_id);
/* Not specified by any standard per-se, however it breaks too
* many applications when removed. It is unfortunate since
* allowing applications to make a non-local bind solves
* several problems with systems using dynamic addressing.
* (ie. your servers still start up even if your ISDN link
* is temporarily down)
*/
err = -EADDRNOTAVAIL;
if (!inet_addr_valid_or_nonlocal(net, inet, addr->sin_addr.s_addr,
chk_addr_ret))
goto out;
snum = ntohs(addr->sin_port);
err = -EACCES;
if (!(flags & BIND_NO_CAP_NET_BIND_SERVICE) &&
snum && inet_port_requires_bind_service(net, snum) &&
!ns_capable(net->user_ns, CAP_NET_BIND_SERVICE))
goto out;
/* We keep a pair of addresses. rcv_saddr is the one
* used by hash lookups, and saddr is used for transmit.
*
* In the BSD API these are the same except where it
* would be illegal to use them (multicast/broadcast) in
* which case the sending device address is used.
*/
if (flags & BIND_WITH_LOCK)
lock_sock(sk);
/* Check these errors (active socket, double bind). */
err = -EINVAL;
if (sk->sk_state != TCP_CLOSE || inet->inet_num)
goto out_release_sock;
inet->inet_rcv_saddr = inet->inet_saddr = addr->sin_addr.s_addr;
if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
inet->inet_saddr = 0; /* Use device */
/* Make sure we are allowed to bind here. */
if (snum || !(inet->bind_address_no_port ||
(flags & BIND_FORCE_ADDRESS_NO_PORT))) {
err = sk->sk_prot->get_port(sk, snum);
if (err) {
inet->inet_saddr = inet->inet_rcv_saddr = 0;
goto out_release_sock;
}
if (!(flags & BIND_FROM_BPF)) {
err = BPF_CGROUP_RUN_PROG_INET4_POST_BIND(sk);
if (err) {
inet->inet_saddr = inet->inet_rcv_saddr = 0;
if (sk->sk_prot->put_port)
sk->sk_prot->put_port(sk);
goto out_release_sock;
}
}
}
if (inet->inet_rcv_saddr)
sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
if (snum)
sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
inet->inet_sport = htons(inet->inet_num);
inet->inet_daddr = 0;
inet->inet_dport = 0;
sk_dst_reset(sk);
err = 0;
out_release_sock:
if (flags & BIND_WITH_LOCK)
release_sock(sk);
out:
return err;
}
int inet_dgram_connect(struct socket *sock, struct sockaddr *uaddr,
int addr_len, int flags)
{
struct sock *sk = sock->sk;
const struct proto *prot;
int err;
if (addr_len < sizeof(uaddr->sa_family))
return -EINVAL;
/* IPV6_ADDRFORM can change sk->sk_prot under us. */
prot = READ_ONCE(sk->sk_prot);
if (uaddr->sa_family == AF_UNSPEC)
return prot->disconnect(sk, flags);
if (BPF_CGROUP_PRE_CONNECT_ENABLED(sk)) {
err = prot->pre_connect(sk, uaddr, addr_len);
if (err)
return err;
}
if (data_race(!inet_sk(sk)->inet_num) && inet_autobind(sk))
return -EAGAIN;
return prot->connect(sk, uaddr, addr_len);
}
EXPORT_SYMBOL(inet_dgram_connect);
static long inet_wait_for_connect(struct sock *sk, long timeo, int writebias)
{
DEFINE_WAIT_FUNC(wait, woken_wake_function);
add_wait_queue(sk_sleep(sk), &wait);
sk->sk_write_pending += writebias;
sk->sk_wait_pending++;
/* Basic assumption: if someone sets sk->sk_err, he _must_
* change state of the socket from TCP_SYN_*.
* Connect() does not allow to get error notifications
* without closing the socket.
*/
while ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
release_sock(sk);
timeo = wait_woken(&wait, TASK_INTERRUPTIBLE, timeo);
lock_sock(sk);
if (signal_pending(current) || !timeo)
break;
}
remove_wait_queue(sk_sleep(sk), &wait);
sk->sk_write_pending -= writebias;
sk->sk_wait_pending--;
return timeo;
}
/*
* Connect to a remote host. There is regrettably still a little
* TCP 'magic' in here.
*/
int __inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
int addr_len, int flags, int is_sendmsg)
{
struct sock *sk = sock->sk;
int err;
long timeo;
/*
* uaddr can be NULL and addr_len can be 0 if:
* sk is a TCP fastopen active socket and
* TCP_FASTOPEN_CONNECT sockopt is set and
* we already have a valid cookie for this socket.
* In this case, user can call write() after connect().
* write() will invoke tcp_sendmsg_fastopen() which calls
* __inet_stream_connect().
*/
if (uaddr) {
if (addr_len < sizeof(uaddr->sa_family))
return -EINVAL;
if (uaddr->sa_family == AF_UNSPEC) {
err = sk->sk_prot->disconnect(sk, flags);
sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
goto out;
}
}
switch (sock->state) {
default:
err = -EINVAL;
goto out;
case SS_CONNECTED:
err = -EISCONN;
goto out;
case SS_CONNECTING:
if (inet_sk(sk)->defer_connect)
err = is_sendmsg ? -EINPROGRESS : -EISCONN;
else
err = -EALREADY;
/* Fall out of switch with err, set for this state */
break;
case SS_UNCONNECTED:
err = -EISCONN;
if (sk->sk_state != TCP_CLOSE)
goto out;
if (BPF_CGROUP_PRE_CONNECT_ENABLED(sk)) {
err = sk->sk_prot->pre_connect(sk, uaddr, addr_len);
if (err)
goto out;
}
err = sk->sk_prot->connect(sk, uaddr, addr_len);
if (err < 0)
goto out;
sock->state = SS_CONNECTING;
if (!err && inet_sk(sk)->defer_connect)
goto out;
/* Just entered SS_CONNECTING state; the only
* difference is that return value in non-blocking
* case is EINPROGRESS, rather than EALREADY.
*/
err = -EINPROGRESS;
break;
}
timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
int writebias = (sk->sk_protocol == IPPROTO_TCP) &&
tcp_sk(sk)->fastopen_req &&
tcp_sk(sk)->fastopen_req->data ? 1 : 0;
/* Error code is set above */
if (!timeo || !inet_wait_for_connect(sk, timeo, writebias))
goto out;
err = sock_intr_errno(timeo);
if (signal_pending(current))
goto out;
}
/* Connection was closed by RST, timeout, ICMP error
* or another process disconnected us.
*/
if (sk->sk_state == TCP_CLOSE)
goto sock_error;
/* sk->sk_err may be not zero now, if RECVERR was ordered by user
* and error was received after socket entered established state.
* Hence, it is handled normally after connect() return successfully.
*/
sock->state = SS_CONNECTED;
err = 0;
out:
return err;
sock_error:
err = sock_error(sk) ? : -ECONNABORTED;
sock->state = SS_UNCONNECTED;
if (sk->sk_prot->disconnect(sk, flags))
sock->state = SS_DISCONNECTING;
goto out;
}
EXPORT_SYMBOL(__inet_stream_connect);
int inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
int addr_len, int flags)
{
int err;
lock_sock(sock->sk);
err = __inet_stream_connect(sock, uaddr, addr_len, flags, 0);
release_sock(sock->sk);
return err;
}
EXPORT_SYMBOL(inet_stream_connect);
/*
* Accept a pending connection. The TCP layer now gives BSD semantics.
*/
int inet_accept(struct socket *sock, struct socket *newsock, int flags,
bool kern)
{
struct sock *sk1 = sock->sk, *sk2;
int err = -EINVAL;
/* IPV6_ADDRFORM can change sk->sk_prot under us. */
sk2 = READ_ONCE(sk1->sk_prot)->accept(sk1, flags, &err, kern);
if (!sk2)
goto do_err;
lock_sock(sk2);
sock_rps_record_flow(sk2);
WARN_ON(!((1 << sk2->sk_state) &
(TCPF_ESTABLISHED | TCPF_SYN_RECV |
TCPF_CLOSE_WAIT | TCPF_CLOSE)));
if (test_bit(SOCK_SUPPORT_ZC, &sock->flags))
set_bit(SOCK_SUPPORT_ZC, &newsock->flags);
sock_graft(sk2, newsock);
newsock->state = SS_CONNECTED;
err = 0;
release_sock(sk2);
do_err:
return err;
}
EXPORT_SYMBOL(inet_accept);
/*
* This does both peername and sockname.
*/
int inet_getname(struct socket *sock, struct sockaddr *uaddr,
int peer)
{
struct sock *sk = sock->sk;
struct inet_sock *inet = inet_sk(sk);
DECLARE_SOCKADDR(struct sockaddr_in *, sin, uaddr);
sin->sin_family = AF_INET;
lock_sock(sk);
if (peer) {
if (!inet->inet_dport ||
(((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
peer == 1)) {
release_sock(sk);
return -ENOTCONN;
}
sin->sin_port = inet->inet_dport;
sin->sin_addr.s_addr = inet->inet_daddr;
BPF_CGROUP_RUN_SA_PROG(sk, (struct sockaddr *)sin,
CGROUP_INET4_GETPEERNAME);
} else {
__be32 addr = inet->inet_rcv_saddr;
if (!addr)
addr = inet->inet_saddr;
sin->sin_port = inet->inet_sport;
sin->sin_addr.s_addr = addr;
BPF_CGROUP_RUN_SA_PROG(sk, (struct sockaddr *)sin,
CGROUP_INET4_GETSOCKNAME);
}
release_sock(sk);
memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
return sizeof(*sin);
}
EXPORT_SYMBOL(inet_getname);
int inet_send_prepare(struct sock *sk)
{
sock_rps_record_flow(sk);
/* We may need to bind the socket. */
if (data_race(!inet_sk(sk)->inet_num) && !sk->sk_prot->no_autobind &&
inet_autobind(sk))
return -EAGAIN;
return 0;
}
EXPORT_SYMBOL_GPL(inet_send_prepare);
int inet_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
{
struct sock *sk = sock->sk;
if (unlikely(inet_send_prepare(sk)))
return -EAGAIN;
return INDIRECT_CALL_2(sk->sk_prot->sendmsg, tcp_sendmsg, udp_sendmsg,
sk, msg, size);
}
EXPORT_SYMBOL(inet_sendmsg);
ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset,
size_t size, int flags)
{
struct sock *sk = sock->sk;
const struct proto *prot;
if (unlikely(inet_send_prepare(sk)))
return -EAGAIN;
/* IPV6_ADDRFORM can change sk->sk_prot under us. */
prot = READ_ONCE(sk->sk_prot);
if (prot->sendpage)
return prot->sendpage(sk, page, offset, size, flags);
return sock_no_sendpage(sock, page, offset, size, flags);
}
EXPORT_SYMBOL(inet_sendpage);
INDIRECT_CALLABLE_DECLARE(int udp_recvmsg(struct sock *, struct msghdr *,
size_t, int, int *));
int inet_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
int flags)
{
struct sock *sk = sock->sk;
int addr_len = 0;
int err;
if (likely(!(flags & MSG_ERRQUEUE)))
sock_rps_record_flow(sk);
err = INDIRECT_CALL_2(sk->sk_prot->recvmsg, tcp_recvmsg, udp_recvmsg,
sk, msg, size, flags, &addr_len);
if (err >= 0)
msg->msg_namelen = addr_len;
return err;
}
EXPORT_SYMBOL(inet_recvmsg);
int inet_shutdown(struct socket *sock, int how)
{
struct sock *sk = sock->sk;
int err = 0;
/* This should really check to make sure
* the socket is a TCP socket. (WHY AC...)
*/
how++; /* maps 0->1 has the advantage of making bit 1 rcvs and
1->2 bit 2 snds.
2->3 */
if ((how & ~SHUTDOWN_MASK) || !how) /* MAXINT->0 */
return -EINVAL;
lock_sock(sk);
if (sock->state == SS_CONNECTING) {
if ((1 << sk->sk_state) &
(TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_CLOSE))
sock->state = SS_DISCONNECTING;
else
sock->state = SS_CONNECTED;
}
switch (sk->sk_state) {
case TCP_CLOSE:
err = -ENOTCONN;
/* Hack to wake up other listeners, who can poll for
EPOLLHUP, even on eg. unconnected UDP sockets -- RR */
fallthrough;
default:
WRITE_ONCE(sk->sk_shutdown, sk->sk_shutdown | how);
if (sk->sk_prot->shutdown)
sk->sk_prot->shutdown(sk, how);
break;
/* Remaining two branches are temporary solution for missing
* close() in multithreaded environment. It is _not_ a good idea,
* but we have no choice until close() is repaired at VFS level.
*/
case TCP_LISTEN:
if (!(how & RCV_SHUTDOWN))
break;
fallthrough;
case TCP_SYN_SENT:
err = sk->sk_prot->disconnect(sk, O_NONBLOCK);
sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
break;
}
/* Wake up anyone sleeping in poll. */
sk->sk_state_change(sk);
release_sock(sk);
return err;
}
EXPORT_SYMBOL(inet_shutdown);
/*
* ioctl() calls you can issue on an INET socket. Most of these are
* device configuration and stuff and very rarely used. Some ioctls
* pass on to the socket itself.
*
* NOTE: I like the idea of a module for the config stuff. ie ifconfig
* loads the devconfigure module does its configuring and unloads it.
* There's a good 20K of config code hanging around the kernel.
*/
int inet_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
{
struct sock *sk = sock->sk;
int err = 0;
struct net *net = sock_net(sk);
void __user *p = (void __user *)arg;
struct ifreq ifr;
struct rtentry rt;
switch (cmd) {
case SIOCADDRT:
case SIOCDELRT:
if (copy_from_user(&rt, p, sizeof(struct rtentry)))
return -EFAULT;
err = ip_rt_ioctl(net, cmd, &rt);
break;
case SIOCRTMSG:
err = -EINVAL;
break;
case SIOCDARP:
case SIOCGARP:
case SIOCSARP:
err = arp_ioctl(net, cmd, (void __user *)arg);
break;
case SIOCGIFADDR:
case SIOCGIFBRDADDR:
case SIOCGIFNETMASK:
case SIOCGIFDSTADDR:
case SIOCGIFPFLAGS:
if (get_user_ifreq(&ifr, NULL, p))
return -EFAULT;
err = devinet_ioctl(net, cmd, &ifr);
if (!err && put_user_ifreq(&ifr, p))
err = -EFAULT;
break;
case SIOCSIFADDR:
case SIOCSIFBRDADDR:
case SIOCSIFNETMASK:
case SIOCSIFDSTADDR:
case SIOCSIFPFLAGS:
case SIOCSIFFLAGS:
if (get_user_ifreq(&ifr, NULL, p))
return -EFAULT;
err = devinet_ioctl(net, cmd, &ifr);
break;
default:
if (sk->sk_prot->ioctl)
err = sk->sk_prot->ioctl(sk, cmd, arg);
else
err = -ENOIOCTLCMD;
break;
}
return err;
}
EXPORT_SYMBOL(inet_ioctl);
#ifdef CONFIG_COMPAT
static int inet_compat_routing_ioctl(struct sock *sk, unsigned int cmd,
struct compat_rtentry __user *ur)
{
compat_uptr_t rtdev;
struct rtentry rt;
if (copy_from_user(&rt.rt_dst, &ur->rt_dst,
3 * sizeof(struct sockaddr)) ||