freebsd-dev/sys/kern/uipc_syscalls.c
Mark Johnston a8aa6f1f78 socket: Avoid clearing SS_ISCONNECTING if soconnect() fails
This behaviour appears to date from the 4.4 BSD import.  It has two
problems:

1. The update to so_state is not protected by the socket lock, so
   concurrent updates to so_state may be lost.
2. Suppose two threads race to call connect(2) on a socket, and one
   succeeds while the other fails.  Then the failing thread may
   incorrectly clear SS_ISCONNECTING, confusing the state machine.

Simply remove the update.  It does not appear to be necessary:
pru_connect implementations which call soisconnecting() only do so after
all failure modes have been handled.  For instance, tcp_connect() and
tcp6_connect() will never return an error after calling soisconnected().
However, we cannot correctly assert that SS_ISCONNECTED is not set after
an error from soconnect() since the socket lock is not held across the
pru_connect call, so a concurrent connect(2) may have set the flag.

MFC after:	1 month
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D31699
2021-09-07 17:12:09 -04:00

1625 lines
36 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1982, 1986, 1989, 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)uipc_syscalls.c 8.4 (Berkeley) 2/21/94
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_capsicum.h"
#include "opt_inet.h"
#include "opt_inet6.h"
#include "opt_ktrace.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/capsicum.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/sysproto.h>
#include <sys/malloc.h>
#include <sys/filedesc.h>
#include <sys/proc.h>
#include <sys/filio.h>
#include <sys/jail.h>
#include <sys/mbuf.h>
#include <sys/protosw.h>
#include <sys/rwlock.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/syscallsubr.h>
#include <sys/sysent.h>
#include <sys/uio.h>
#include <sys/un.h>
#include <sys/unpcb.h>
#ifdef KTRACE
#include <sys/ktrace.h>
#endif
#ifdef COMPAT_FREEBSD32
#include <compat/freebsd32/freebsd32_util.h>
#endif
#include <net/vnet.h>
#include <security/audit/audit.h>
#include <security/mac/mac_framework.h>
static int sendit(struct thread *td, int s, struct msghdr *mp, int flags);
static int recvit(struct thread *td, int s, struct msghdr *mp, void *namelenp);
static int accept1(struct thread *td, int s, struct sockaddr *uname,
socklen_t *anamelen, int flags);
static int getsockname1(struct thread *td, struct getsockname_args *uap,
int compat);
static int getpeername1(struct thread *td, struct getpeername_args *uap,
int compat);
static int sockargs(struct mbuf **, char *, socklen_t, int);
/*
* Convert a user file descriptor to a kernel file entry and check if required
* capability rights are present.
* If required copy of current set of capability rights is returned.
* A reference on the file entry is held upon returning.
*/
int
getsock_cap(struct thread *td, int fd, cap_rights_t *rightsp,
struct file **fpp, u_int *fflagp, struct filecaps *havecapsp)
{
struct file *fp;
int error;
error = fget_cap(td, fd, rightsp, &fp, havecapsp);
if (error != 0)
return (error);
if (fp->f_type != DTYPE_SOCKET) {
fdrop(fp, td);
if (havecapsp != NULL)
filecaps_free(havecapsp);
return (ENOTSOCK);
}
if (fflagp != NULL)
*fflagp = fp->f_flag;
*fpp = fp;
return (0);
}
/*
* System call interface to the socket abstraction.
*/
#if defined(COMPAT_43)
#define COMPAT_OLDSOCK
#endif
int
sys_socket(struct thread *td, struct socket_args *uap)
{
return (kern_socket(td, uap->domain, uap->type, uap->protocol));
}
int
kern_socket(struct thread *td, int domain, int type, int protocol)
{
struct socket *so;
struct file *fp;
int fd, error, oflag, fflag;
AUDIT_ARG_SOCKET(domain, type, protocol);
oflag = 0;
fflag = 0;
if ((type & SOCK_CLOEXEC) != 0) {
type &= ~SOCK_CLOEXEC;
oflag |= O_CLOEXEC;
}
if ((type & SOCK_NONBLOCK) != 0) {
type &= ~SOCK_NONBLOCK;
fflag |= FNONBLOCK;
}
#ifdef MAC
error = mac_socket_check_create(td->td_ucred, domain, type, protocol);
if (error != 0)
return (error);
#endif
error = falloc(td, &fp, &fd, oflag);
if (error != 0)
return (error);
/* An extra reference on `fp' has been held for us by falloc(). */
error = socreate(domain, &so, type, protocol, td->td_ucred, td);
if (error != 0) {
fdclose(td, fp, fd);
} else {
finit(fp, FREAD | FWRITE | fflag, DTYPE_SOCKET, so, &socketops);
if ((fflag & FNONBLOCK) != 0)
(void) fo_ioctl(fp, FIONBIO, &fflag, td->td_ucred, td);
td->td_retval[0] = fd;
}
fdrop(fp, td);
return (error);
}
int
sys_bind(struct thread *td, struct bind_args *uap)
{
struct sockaddr *sa;
int error;
error = getsockaddr(&sa, uap->name, uap->namelen);
if (error == 0) {
error = kern_bindat(td, AT_FDCWD, uap->s, sa);
free(sa, M_SONAME);
}
return (error);
}
int
kern_bindat(struct thread *td, int dirfd, int fd, struct sockaddr *sa)
{
struct socket *so;
struct file *fp;
int error;
#ifdef CAPABILITY_MODE
if (IN_CAPABILITY_MODE(td) && (dirfd == AT_FDCWD))
return (ECAPMODE);
#endif
AUDIT_ARG_FD(fd);
AUDIT_ARG_SOCKADDR(td, dirfd, sa);
error = getsock_cap(td, fd, &cap_bind_rights,
&fp, NULL, NULL);
if (error != 0)
return (error);
so = fp->f_data;
#ifdef KTRACE
if (KTRPOINT(td, KTR_STRUCT))
ktrsockaddr(sa);
#endif
#ifdef MAC
error = mac_socket_check_bind(td->td_ucred, so, sa);
if (error == 0) {
#endif
if (dirfd == AT_FDCWD)
error = sobind(so, sa, td);
else
error = sobindat(dirfd, so, sa, td);
#ifdef MAC
}
#endif
fdrop(fp, td);
return (error);
}
int
sys_bindat(struct thread *td, struct bindat_args *uap)
{
struct sockaddr *sa;
int error;
error = getsockaddr(&sa, uap->name, uap->namelen);
if (error == 0) {
error = kern_bindat(td, uap->fd, uap->s, sa);
free(sa, M_SONAME);
}
return (error);
}
int
sys_listen(struct thread *td, struct listen_args *uap)
{
return (kern_listen(td, uap->s, uap->backlog));
}
int
kern_listen(struct thread *td, int s, int backlog)
{
struct socket *so;
struct file *fp;
int error;
AUDIT_ARG_FD(s);
error = getsock_cap(td, s, &cap_listen_rights,
&fp, NULL, NULL);
if (error == 0) {
so = fp->f_data;
#ifdef MAC
error = mac_socket_check_listen(td->td_ucred, so);
if (error == 0)
#endif
error = solisten(so, backlog, td);
fdrop(fp, td);
}
return (error);
}
/*
* accept1()
*/
static int
accept1(td, s, uname, anamelen, flags)
struct thread *td;
int s;
struct sockaddr *uname;
socklen_t *anamelen;
int flags;
{
struct sockaddr *name;
socklen_t namelen;
struct file *fp;
int error;
if (uname == NULL)
return (kern_accept4(td, s, NULL, NULL, flags, NULL));
error = copyin(anamelen, &namelen, sizeof (namelen));
if (error != 0)
return (error);
error = kern_accept4(td, s, &name, &namelen, flags, &fp);
if (error != 0)
return (error);
if (error == 0 && uname != NULL) {
#ifdef COMPAT_OLDSOCK
if (SV_PROC_FLAG(td->td_proc, SV_AOUT) &&
(flags & ACCEPT4_COMPAT) != 0)
((struct osockaddr *)name)->sa_family =
name->sa_family;
#endif
error = copyout(name, uname, namelen);
}
if (error == 0)
error = copyout(&namelen, anamelen,
sizeof(namelen));
if (error != 0)
fdclose(td, fp, td->td_retval[0]);
fdrop(fp, td);
free(name, M_SONAME);
return (error);
}
int
kern_accept(struct thread *td, int s, struct sockaddr **name,
socklen_t *namelen, struct file **fp)
{
return (kern_accept4(td, s, name, namelen, ACCEPT4_INHERIT, fp));
}
int
kern_accept4(struct thread *td, int s, struct sockaddr **name,
socklen_t *namelen, int flags, struct file **fp)
{
struct file *headfp, *nfp = NULL;
struct sockaddr *sa = NULL;
struct socket *head, *so;
struct filecaps fcaps;
u_int fflag;
pid_t pgid;
int error, fd, tmp;
if (name != NULL)
*name = NULL;
AUDIT_ARG_FD(s);
error = getsock_cap(td, s, &cap_accept_rights,
&headfp, &fflag, &fcaps);
if (error != 0)
return (error);
head = headfp->f_data;
if (!SOLISTENING(head)) {
error = EINVAL;
goto done;
}
#ifdef MAC
error = mac_socket_check_accept(td->td_ucred, head);
if (error != 0)
goto done;
#endif
error = falloc_caps(td, &nfp, &fd,
(flags & SOCK_CLOEXEC) ? O_CLOEXEC : 0, &fcaps);
if (error != 0)
goto done;
SOCK_LOCK(head);
if (!SOLISTENING(head)) {
SOCK_UNLOCK(head);
error = EINVAL;
goto noconnection;
}
error = solisten_dequeue(head, &so, flags);
if (error != 0)
goto noconnection;
/* An extra reference on `nfp' has been held for us by falloc(). */
td->td_retval[0] = fd;
/* Connection has been removed from the listen queue. */
KNOTE_UNLOCKED(&head->so_rdsel.si_note, 0);
if (flags & ACCEPT4_INHERIT) {
pgid = fgetown(&head->so_sigio);
if (pgid != 0)
fsetown(pgid, &so->so_sigio);
} else {
fflag &= ~(FNONBLOCK | FASYNC);
if (flags & SOCK_NONBLOCK)
fflag |= FNONBLOCK;
}
finit(nfp, fflag, DTYPE_SOCKET, so, &socketops);
/* Sync socket nonblocking/async state with file flags */
tmp = fflag & FNONBLOCK;
(void) fo_ioctl(nfp, FIONBIO, &tmp, td->td_ucred, td);
tmp = fflag & FASYNC;
(void) fo_ioctl(nfp, FIOASYNC, &tmp, td->td_ucred, td);
error = soaccept(so, &sa);
if (error != 0)
goto noconnection;
if (sa == NULL) {
if (name)
*namelen = 0;
goto done;
}
AUDIT_ARG_SOCKADDR(td, AT_FDCWD, sa);
if (name) {
/* check sa_len before it is destroyed */
if (*namelen > sa->sa_len)
*namelen = sa->sa_len;
#ifdef KTRACE
if (KTRPOINT(td, KTR_STRUCT))
ktrsockaddr(sa);
#endif
*name = sa;
sa = NULL;
}
noconnection:
free(sa, M_SONAME);
/*
* close the new descriptor, assuming someone hasn't ripped it
* out from under us.
*/
if (error != 0)
fdclose(td, nfp, fd);
/*
* Release explicitly held references before returning. We return
* a reference on nfp to the caller on success if they request it.
*/
done:
if (nfp == NULL)
filecaps_free(&fcaps);
if (fp != NULL) {
if (error == 0) {
*fp = nfp;
nfp = NULL;
} else
*fp = NULL;
}
if (nfp != NULL)
fdrop(nfp, td);
fdrop(headfp, td);
return (error);
}
int
sys_accept(td, uap)
struct thread *td;
struct accept_args *uap;
{
return (accept1(td, uap->s, uap->name, uap->anamelen, ACCEPT4_INHERIT));
}
int
sys_accept4(td, uap)
struct thread *td;
struct accept4_args *uap;
{
if (uap->flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
return (EINVAL);
return (accept1(td, uap->s, uap->name, uap->anamelen, uap->flags));
}
#ifdef COMPAT_OLDSOCK
int
oaccept(struct thread *td, struct oaccept_args *uap)
{
return (accept1(td, uap->s, uap->name, uap->anamelen,
ACCEPT4_INHERIT | ACCEPT4_COMPAT));
}
#endif /* COMPAT_OLDSOCK */
int
sys_connect(struct thread *td, struct connect_args *uap)
{
struct sockaddr *sa;
int error;
error = getsockaddr(&sa, uap->name, uap->namelen);
if (error == 0) {
error = kern_connectat(td, AT_FDCWD, uap->s, sa);
free(sa, M_SONAME);
}
return (error);
}
int
kern_connectat(struct thread *td, int dirfd, int fd, struct sockaddr *sa)
{
struct socket *so;
struct file *fp;
int error;
#ifdef CAPABILITY_MODE
if (IN_CAPABILITY_MODE(td) && (dirfd == AT_FDCWD))
return (ECAPMODE);
#endif
AUDIT_ARG_FD(fd);
AUDIT_ARG_SOCKADDR(td, dirfd, sa);
error = getsock_cap(td, fd, &cap_connect_rights,
&fp, NULL, NULL);
if (error != 0)
return (error);
so = fp->f_data;
if (so->so_state & SS_ISCONNECTING) {
error = EALREADY;
goto done1;
}
#ifdef KTRACE
if (KTRPOINT(td, KTR_STRUCT))
ktrsockaddr(sa);
#endif
#ifdef MAC
error = mac_socket_check_connect(td->td_ucred, so, sa);
if (error != 0)
goto bad;
#endif
error = soconnectat(dirfd, so, sa, td);
if (error != 0)
goto bad;
if ((so->so_state & SS_NBIO) && (so->so_state & SS_ISCONNECTING)) {
error = EINPROGRESS;
goto done1;
}
SOCK_LOCK(so);
while ((so->so_state & SS_ISCONNECTING) && so->so_error == 0) {
error = msleep(&so->so_timeo, &so->so_lock, PSOCK | PCATCH,
"connec", 0);
if (error != 0)
break;
}
if (error == 0) {
error = so->so_error;
so->so_error = 0;
}
SOCK_UNLOCK(so);
bad:
if (error == ERESTART)
error = EINTR;
done1:
fdrop(fp, td);
return (error);
}
int
sys_connectat(struct thread *td, struct connectat_args *uap)
{
struct sockaddr *sa;
int error;
error = getsockaddr(&sa, uap->name, uap->namelen);
if (error == 0) {
error = kern_connectat(td, uap->fd, uap->s, sa);
free(sa, M_SONAME);
}
return (error);
}
int
kern_socketpair(struct thread *td, int domain, int type, int protocol,
int *rsv)
{
struct file *fp1, *fp2;
struct socket *so1, *so2;
int fd, error, oflag, fflag;
AUDIT_ARG_SOCKET(domain, type, protocol);
oflag = 0;
fflag = 0;
if ((type & SOCK_CLOEXEC) != 0) {
type &= ~SOCK_CLOEXEC;
oflag |= O_CLOEXEC;
}
if ((type & SOCK_NONBLOCK) != 0) {
type &= ~SOCK_NONBLOCK;
fflag |= FNONBLOCK;
}
#ifdef MAC
/* We might want to have a separate check for socket pairs. */
error = mac_socket_check_create(td->td_ucred, domain, type,
protocol);
if (error != 0)
return (error);
#endif
error = socreate(domain, &so1, type, protocol, td->td_ucred, td);
if (error != 0)
return (error);
error = socreate(domain, &so2, type, protocol, td->td_ucred, td);
if (error != 0)
goto free1;
/* On success extra reference to `fp1' and 'fp2' is set by falloc. */
error = falloc(td, &fp1, &fd, oflag);
if (error != 0)
goto free2;
rsv[0] = fd;
fp1->f_data = so1; /* so1 already has ref count */
error = falloc(td, &fp2, &fd, oflag);
if (error != 0)
goto free3;
fp2->f_data = so2; /* so2 already has ref count */
rsv[1] = fd;
error = soconnect2(so1, so2);
if (error != 0)
goto free4;
if (type == SOCK_DGRAM) {
/*
* Datagram socket connection is asymmetric.
*/
error = soconnect2(so2, so1);
if (error != 0)
goto free4;
} else if (so1->so_proto->pr_flags & PR_CONNREQUIRED) {
struct unpcb *unp, *unp2;
unp = sotounpcb(so1);
unp2 = sotounpcb(so2);
/*
* No need to lock the unps, because the sockets are brand-new.
* No other threads can be using them yet
*/
unp_copy_peercred(td, unp, unp2, unp);
}
finit(fp1, FREAD | FWRITE | fflag, DTYPE_SOCKET, fp1->f_data,
&socketops);
finit(fp2, FREAD | FWRITE | fflag, DTYPE_SOCKET, fp2->f_data,
&socketops);
if ((fflag & FNONBLOCK) != 0) {
(void) fo_ioctl(fp1, FIONBIO, &fflag, td->td_ucred, td);
(void) fo_ioctl(fp2, FIONBIO, &fflag, td->td_ucred, td);
}
fdrop(fp1, td);
fdrop(fp2, td);
return (0);
free4:
fdclose(td, fp2, rsv[1]);
fdrop(fp2, td);
free3:
fdclose(td, fp1, rsv[0]);
fdrop(fp1, td);
free2:
if (so2 != NULL)
(void)soclose(so2);
free1:
if (so1 != NULL)
(void)soclose(so1);
return (error);
}
int
sys_socketpair(struct thread *td, struct socketpair_args *uap)
{
int error, sv[2];
error = kern_socketpair(td, uap->domain, uap->type,
uap->protocol, sv);
if (error != 0)
return (error);
error = copyout(sv, uap->rsv, 2 * sizeof(int));
if (error != 0) {
(void)kern_close(td, sv[0]);
(void)kern_close(td, sv[1]);
}
return (error);
}
static int
sendit(struct thread *td, int s, struct msghdr *mp, int flags)
{
struct mbuf *control;
struct sockaddr *to;
int error;
#ifdef CAPABILITY_MODE
if (IN_CAPABILITY_MODE(td) && (mp->msg_name != NULL))
return (ECAPMODE);
#endif
if (mp->msg_name != NULL) {
error = getsockaddr(&to, mp->msg_name, mp->msg_namelen);
if (error != 0) {
to = NULL;
goto bad;
}
mp->msg_name = to;
} else {
to = NULL;
}
if (mp->msg_control) {
if (mp->msg_controllen < sizeof(struct cmsghdr)
#ifdef COMPAT_OLDSOCK
&& (mp->msg_flags != MSG_COMPAT ||
!SV_PROC_FLAG(td->td_proc, SV_AOUT))
#endif
) {
error = EINVAL;
goto bad;
}
error = sockargs(&control, mp->msg_control,
mp->msg_controllen, MT_CONTROL);
if (error != 0)
goto bad;
#ifdef COMPAT_OLDSOCK
if (mp->msg_flags == MSG_COMPAT &&
SV_PROC_FLAG(td->td_proc, SV_AOUT)) {
struct cmsghdr *cm;
M_PREPEND(control, sizeof(*cm), M_WAITOK);
cm = mtod(control, struct cmsghdr *);
cm->cmsg_len = control->m_len;
cm->cmsg_level = SOL_SOCKET;
cm->cmsg_type = SCM_RIGHTS;
}
#endif
} else {
control = NULL;
}
error = kern_sendit(td, s, mp, flags, control, UIO_USERSPACE);
bad:
free(to, M_SONAME);
return (error);
}
int
kern_sendit(struct thread *td, int s, struct msghdr *mp, int flags,
struct mbuf *control, enum uio_seg segflg)
{
struct file *fp;
struct uio auio;
struct iovec *iov;
struct socket *so;
cap_rights_t *rights;
#ifdef KTRACE
struct uio *ktruio = NULL;
#endif
ssize_t len;
int i, error;
AUDIT_ARG_FD(s);
rights = &cap_send_rights;
if (mp->msg_name != NULL) {
AUDIT_ARG_SOCKADDR(td, AT_FDCWD, mp->msg_name);
rights = &cap_send_connect_rights;
}
error = getsock_cap(td, s, rights, &fp, NULL, NULL);
if (error != 0) {
m_freem(control);
return (error);
}
so = (struct socket *)fp->f_data;
#ifdef KTRACE
if (mp->msg_name != NULL && KTRPOINT(td, KTR_STRUCT))
ktrsockaddr(mp->msg_name);
#endif
#ifdef MAC
if (mp->msg_name != NULL) {
error = mac_socket_check_connect(td->td_ucred, so,
mp->msg_name);
if (error != 0) {
m_freem(control);
goto bad;
}
}
error = mac_socket_check_send(td->td_ucred, so);
if (error != 0) {
m_freem(control);
goto bad;
}
#endif
auio.uio_iov = mp->msg_iov;
auio.uio_iovcnt = mp->msg_iovlen;
auio.uio_segflg = segflg;
auio.uio_rw = UIO_WRITE;
auio.uio_td = td;
auio.uio_offset = 0; /* XXX */
auio.uio_resid = 0;
iov = mp->msg_iov;
for (i = 0; i < mp->msg_iovlen; i++, iov++) {
if ((auio.uio_resid += iov->iov_len) < 0) {
error = EINVAL;
m_freem(control);
goto bad;
}
}
#ifdef KTRACE
if (KTRPOINT(td, KTR_GENIO))
ktruio = cloneuio(&auio);
#endif
len = auio.uio_resid;
error = sosend(so, mp->msg_name, &auio, 0, control, flags, td);
if (error != 0) {
if (auio.uio_resid != len && (error == ERESTART ||
error == EINTR || error == EWOULDBLOCK))
error = 0;
/* Generation of SIGPIPE can be controlled per socket */
if (error == EPIPE && !(so->so_options & SO_NOSIGPIPE) &&
!(flags & MSG_NOSIGNAL)) {
PROC_LOCK(td->td_proc);
tdsignal(td, SIGPIPE);
PROC_UNLOCK(td->td_proc);
}
}
if (error == 0)
td->td_retval[0] = len - auio.uio_resid;
#ifdef KTRACE
if (ktruio != NULL) {
ktruio->uio_resid = td->td_retval[0];
ktrgenio(s, UIO_WRITE, ktruio, error);
}
#endif
bad:
fdrop(fp, td);
return (error);
}
int
sys_sendto(struct thread *td, struct sendto_args *uap)
{
struct msghdr msg;
struct iovec aiov;
msg.msg_name = __DECONST(void *, uap->to);
msg.msg_namelen = uap->tolen;
msg.msg_iov = &aiov;
msg.msg_iovlen = 1;
msg.msg_control = 0;
#ifdef COMPAT_OLDSOCK
if (SV_PROC_FLAG(td->td_proc, SV_AOUT))
msg.msg_flags = 0;
#endif
aiov.iov_base = __DECONST(void *, uap->buf);
aiov.iov_len = uap->len;
return (sendit(td, uap->s, &msg, uap->flags));
}
#ifdef COMPAT_OLDSOCK
int
osend(struct thread *td, struct osend_args *uap)
{
struct msghdr msg;
struct iovec aiov;
msg.msg_name = 0;
msg.msg_namelen = 0;
msg.msg_iov = &aiov;
msg.msg_iovlen = 1;
aiov.iov_base = __DECONST(void *, uap->buf);
aiov.iov_len = uap->len;
msg.msg_control = 0;
msg.msg_flags = 0;
return (sendit(td, uap->s, &msg, uap->flags));
}
int
osendmsg(struct thread *td, struct osendmsg_args *uap)
{
struct msghdr msg;
struct iovec *iov;
int error;
error = copyin(uap->msg, &msg, sizeof (struct omsghdr));
if (error != 0)
return (error);
error = copyiniov(msg.msg_iov, msg.msg_iovlen, &iov, EMSGSIZE);
if (error != 0)
return (error);
msg.msg_iov = iov;
msg.msg_flags = MSG_COMPAT;
error = sendit(td, uap->s, &msg, uap->flags);
free(iov, M_IOV);
return (error);
}
#endif
int
sys_sendmsg(struct thread *td, struct sendmsg_args *uap)
{
struct msghdr msg;
struct iovec *iov;
int error;
error = copyin(uap->msg, &msg, sizeof (msg));
if (error != 0)
return (error);
error = copyiniov(msg.msg_iov, msg.msg_iovlen, &iov, EMSGSIZE);
if (error != 0)
return (error);
msg.msg_iov = iov;
#ifdef COMPAT_OLDSOCK
if (SV_PROC_FLAG(td->td_proc, SV_AOUT))
msg.msg_flags = 0;
#endif
error = sendit(td, uap->s, &msg, uap->flags);
free(iov, M_IOV);
return (error);
}
int
kern_recvit(struct thread *td, int s, struct msghdr *mp, enum uio_seg fromseg,
struct mbuf **controlp)
{
struct uio auio;
struct iovec *iov;
struct mbuf *control, *m;
caddr_t ctlbuf;
struct file *fp;
struct socket *so;
struct sockaddr *fromsa = NULL;
#ifdef KTRACE
struct uio *ktruio = NULL;
#endif
ssize_t len;
int error, i;
if (controlp != NULL)
*controlp = NULL;
AUDIT_ARG_FD(s);
error = getsock_cap(td, s, &cap_recv_rights,
&fp, NULL, NULL);
if (error != 0)
return (error);
so = fp->f_data;
#ifdef MAC
error = mac_socket_check_receive(td->td_ucred, so);
if (error != 0) {
fdrop(fp, td);
return (error);
}
#endif
auio.uio_iov = mp->msg_iov;
auio.uio_iovcnt = mp->msg_iovlen;
auio.uio_segflg = UIO_USERSPACE;
auio.uio_rw = UIO_READ;
auio.uio_td = td;
auio.uio_offset = 0; /* XXX */
auio.uio_resid = 0;
iov = mp->msg_iov;
for (i = 0; i < mp->msg_iovlen; i++, iov++) {
if ((auio.uio_resid += iov->iov_len) < 0) {
fdrop(fp, td);
return (EINVAL);
}
}
#ifdef KTRACE
if (KTRPOINT(td, KTR_GENIO))
ktruio = cloneuio(&auio);
#endif
control = NULL;
len = auio.uio_resid;
error = soreceive(so, &fromsa, &auio, NULL,
(mp->msg_control || controlp) ? &control : NULL,
&mp->msg_flags);
if (error != 0) {
if (auio.uio_resid != len && (error == ERESTART ||
error == EINTR || error == EWOULDBLOCK))
error = 0;
}
if (fromsa != NULL)
AUDIT_ARG_SOCKADDR(td, AT_FDCWD, fromsa);
#ifdef KTRACE
if (ktruio != NULL) {
ktruio->uio_resid = len - auio.uio_resid;
ktrgenio(s, UIO_READ, ktruio, error);
}
#endif
if (error != 0)
goto out;
td->td_retval[0] = len - auio.uio_resid;
if (mp->msg_name) {
len = mp->msg_namelen;
if (len <= 0 || fromsa == NULL)
len = 0;
else {
/* save sa_len before it is destroyed by MSG_COMPAT */
len = MIN(len, fromsa->sa_len);
#ifdef COMPAT_OLDSOCK
if ((mp->msg_flags & MSG_COMPAT) != 0 &&
SV_PROC_FLAG(td->td_proc, SV_AOUT))
((struct osockaddr *)fromsa)->sa_family =
fromsa->sa_family;
#endif
if (fromseg == UIO_USERSPACE) {
error = copyout(fromsa, mp->msg_name,
(unsigned)len);
if (error != 0)
goto out;
} else
bcopy(fromsa, mp->msg_name, len);
}
mp->msg_namelen = len;
}
if (mp->msg_control && controlp == NULL) {
#ifdef COMPAT_OLDSOCK
/*
* We assume that old recvmsg calls won't receive access
* rights and other control info, esp. as control info
* is always optional and those options didn't exist in 4.3.
* If we receive rights, trim the cmsghdr; anything else
* is tossed.
*/
if (control && (mp->msg_flags & MSG_COMPAT) != 0 &&
SV_PROC_FLAG(td->td_proc, SV_AOUT)) {
if (mtod(control, struct cmsghdr *)->cmsg_level !=
SOL_SOCKET ||
mtod(control, struct cmsghdr *)->cmsg_type !=
SCM_RIGHTS) {
mp->msg_controllen = 0;
goto out;
}
control->m_len -= sizeof (struct cmsghdr);
control->m_data += sizeof (struct cmsghdr);
}
#endif
ctlbuf = mp->msg_control;
len = mp->msg_controllen;
mp->msg_controllen = 0;
for (m = control; m != NULL && len >= m->m_len; m = m->m_next) {
if ((error = copyout(mtod(m, caddr_t), ctlbuf,
m->m_len)) != 0)
goto out;
ctlbuf += m->m_len;
len -= m->m_len;
mp->msg_controllen += m->m_len;
}
if (m != NULL) {
mp->msg_flags |= MSG_CTRUNC;
m_dispose_extcontrolm(m);
}
}
out:
fdrop(fp, td);
#ifdef KTRACE
if (fromsa && KTRPOINT(td, KTR_STRUCT))
ktrsockaddr(fromsa);
#endif
free(fromsa, M_SONAME);
if (error == 0 && controlp != NULL)
*controlp = control;
else if (control != NULL) {
if (error != 0)
m_dispose_extcontrolm(control);
m_freem(control);
}
return (error);
}
static int
recvit(struct thread *td, int s, struct msghdr *mp, void *namelenp)
{
int error;
error = kern_recvit(td, s, mp, UIO_USERSPACE, NULL);
if (error != 0)
return (error);
if (namelenp != NULL) {
error = copyout(&mp->msg_namelen, namelenp, sizeof (socklen_t));
#ifdef COMPAT_OLDSOCK
if ((mp->msg_flags & MSG_COMPAT) != 0 &&
SV_PROC_FLAG(td->td_proc, SV_AOUT))
error = 0; /* old recvfrom didn't check */
#endif
}
return (error);
}
int
sys_recvfrom(struct thread *td, struct recvfrom_args *uap)
{
struct msghdr msg;
struct iovec aiov;
int error;
if (uap->fromlenaddr) {
error = copyin(uap->fromlenaddr,
&msg.msg_namelen, sizeof (msg.msg_namelen));
if (error != 0)
goto done2;
} else {
msg.msg_namelen = 0;
}
msg.msg_name = uap->from;
msg.msg_iov = &aiov;
msg.msg_iovlen = 1;
aiov.iov_base = uap->buf;
aiov.iov_len = uap->len;
msg.msg_control = 0;
msg.msg_flags = uap->flags;
error = recvit(td, uap->s, &msg, uap->fromlenaddr);
done2:
return (error);
}
#ifdef COMPAT_OLDSOCK
int
orecvfrom(struct thread *td, struct recvfrom_args *uap)
{
uap->flags |= MSG_COMPAT;
return (sys_recvfrom(td, uap));
}
#endif
#ifdef COMPAT_OLDSOCK
int
orecv(struct thread *td, struct orecv_args *uap)
{
struct msghdr msg;
struct iovec aiov;
msg.msg_name = 0;
msg.msg_namelen = 0;
msg.msg_iov = &aiov;
msg.msg_iovlen = 1;
aiov.iov_base = uap->buf;
aiov.iov_len = uap->len;
msg.msg_control = 0;
msg.msg_flags = uap->flags;
return (recvit(td, uap->s, &msg, NULL));
}
/*
* Old recvmsg. This code takes advantage of the fact that the old msghdr
* overlays the new one, missing only the flags, and with the (old) access
* rights where the control fields are now.
*/
int
orecvmsg(struct thread *td, struct orecvmsg_args *uap)
{
struct msghdr msg;
struct iovec *iov;
int error;
error = copyin(uap->msg, &msg, sizeof (struct omsghdr));
if (error != 0)
return (error);
error = copyiniov(msg.msg_iov, msg.msg_iovlen, &iov, EMSGSIZE);
if (error != 0)
return (error);
msg.msg_flags = uap->flags | MSG_COMPAT;
msg.msg_iov = iov;
error = recvit(td, uap->s, &msg, &uap->msg->msg_namelen);
if (msg.msg_controllen && error == 0)
error = copyout(&msg.msg_controllen,
&uap->msg->msg_accrightslen, sizeof (int));
free(iov, M_IOV);
return (error);
}
#endif
int
sys_recvmsg(struct thread *td, struct recvmsg_args *uap)
{
struct msghdr msg;
struct iovec *uiov, *iov;
int error;
error = copyin(uap->msg, &msg, sizeof (msg));
if (error != 0)
return (error);
error = copyiniov(msg.msg_iov, msg.msg_iovlen, &iov, EMSGSIZE);
if (error != 0)
return (error);
msg.msg_flags = uap->flags;
#ifdef COMPAT_OLDSOCK
if (SV_PROC_FLAG(td->td_proc, SV_AOUT))
msg.msg_flags &= ~MSG_COMPAT;
#endif
uiov = msg.msg_iov;
msg.msg_iov = iov;
error = recvit(td, uap->s, &msg, NULL);
if (error == 0) {
msg.msg_iov = uiov;
error = copyout(&msg, uap->msg, sizeof(msg));
}
free(iov, M_IOV);
return (error);
}
int
sys_shutdown(struct thread *td, struct shutdown_args *uap)
{
return (kern_shutdown(td, uap->s, uap->how));
}
int
kern_shutdown(struct thread *td, int s, int how)
{
struct socket *so;
struct file *fp;
int error;
AUDIT_ARG_FD(s);
error = getsock_cap(td, s, &cap_shutdown_rights,
&fp, NULL, NULL);
if (error == 0) {
so = fp->f_data;
error = soshutdown(so, how);
/*
* Previous versions did not return ENOTCONN, but 0 in
* case the socket was not connected. Some important
* programs like syslogd up to r279016, 2015-02-19,
* still depend on this behavior.
*/
if (error == ENOTCONN &&
td->td_proc->p_osrel < P_OSREL_SHUTDOWN_ENOTCONN)
error = 0;
fdrop(fp, td);
}
return (error);
}
int
sys_setsockopt(struct thread *td, struct setsockopt_args *uap)
{
return (kern_setsockopt(td, uap->s, uap->level, uap->name,
uap->val, UIO_USERSPACE, uap->valsize));
}
int
kern_setsockopt(struct thread *td, int s, int level, int name, const void *val,
enum uio_seg valseg, socklen_t valsize)
{
struct socket *so;
struct file *fp;
struct sockopt sopt;
int error;
if (val == NULL && valsize != 0)
return (EFAULT);
if ((int)valsize < 0)
return (EINVAL);
sopt.sopt_dir = SOPT_SET;
sopt.sopt_level = level;
sopt.sopt_name = name;
sopt.sopt_val = __DECONST(void *, val);
sopt.sopt_valsize = valsize;
switch (valseg) {
case UIO_USERSPACE:
sopt.sopt_td = td;
break;
case UIO_SYSSPACE:
sopt.sopt_td = NULL;
break;
default:
panic("kern_setsockopt called with bad valseg");
}
AUDIT_ARG_FD(s);
error = getsock_cap(td, s, &cap_setsockopt_rights,
&fp, NULL, NULL);
if (error == 0) {
so = fp->f_data;
error = sosetopt(so, &sopt);
fdrop(fp, td);
}
return(error);
}
int
sys_getsockopt(struct thread *td, struct getsockopt_args *uap)
{
socklen_t valsize;
int error;
if (uap->val) {
error = copyin(uap->avalsize, &valsize, sizeof (valsize));
if (error != 0)
return (error);
}
error = kern_getsockopt(td, uap->s, uap->level, uap->name,
uap->val, UIO_USERSPACE, &valsize);
if (error == 0)
error = copyout(&valsize, uap->avalsize, sizeof (valsize));
return (error);
}
/*
* Kernel version of getsockopt.
* optval can be a userland or userspace. optlen is always a kernel pointer.
*/
int
kern_getsockopt(struct thread *td, int s, int level, int name, void *val,
enum uio_seg valseg, socklen_t *valsize)
{
struct socket *so;
struct file *fp;
struct sockopt sopt;
int error;
if (val == NULL)
*valsize = 0;
if ((int)*valsize < 0)
return (EINVAL);
sopt.sopt_dir = SOPT_GET;
sopt.sopt_level = level;
sopt.sopt_name = name;
sopt.sopt_val = val;
sopt.sopt_valsize = (size_t)*valsize; /* checked non-negative above */
switch (valseg) {
case UIO_USERSPACE:
sopt.sopt_td = td;
break;
case UIO_SYSSPACE:
sopt.sopt_td = NULL;
break;
default:
panic("kern_getsockopt called with bad valseg");
}
AUDIT_ARG_FD(s);
error = getsock_cap(td, s, &cap_getsockopt_rights,
&fp, NULL, NULL);
if (error == 0) {
so = fp->f_data;
error = sogetopt(so, &sopt);
*valsize = sopt.sopt_valsize;
fdrop(fp, td);
}
return (error);
}
/*
* getsockname1() - Get socket name.
*/
static int
getsockname1(struct thread *td, struct getsockname_args *uap, int compat)
{
struct sockaddr *sa;
socklen_t len;
int error;
error = copyin(uap->alen, &len, sizeof(len));
if (error != 0)
return (error);
error = kern_getsockname(td, uap->fdes, &sa, &len);
if (error != 0)
return (error);
if (len != 0) {
#ifdef COMPAT_OLDSOCK
if (compat && SV_PROC_FLAG(td->td_proc, SV_AOUT))
((struct osockaddr *)sa)->sa_family = sa->sa_family;
#endif
error = copyout(sa, uap->asa, (u_int)len);
}
free(sa, M_SONAME);
if (error == 0)
error = copyout(&len, uap->alen, sizeof(len));
return (error);
}
int
kern_getsockname(struct thread *td, int fd, struct sockaddr **sa,
socklen_t *alen)
{
struct socket *so;
struct file *fp;
socklen_t len;
int error;
AUDIT_ARG_FD(fd);
error = getsock_cap(td, fd, &cap_getsockname_rights,
&fp, NULL, NULL);
if (error != 0)
return (error);
so = fp->f_data;
*sa = NULL;
CURVNET_SET(so->so_vnet);
error = (*so->so_proto->pr_usrreqs->pru_sockaddr)(so, sa);
CURVNET_RESTORE();
if (error != 0)
goto bad;
if (*sa == NULL)
len = 0;
else
len = MIN(*alen, (*sa)->sa_len);
*alen = len;
#ifdef KTRACE
if (KTRPOINT(td, KTR_STRUCT))
ktrsockaddr(*sa);
#endif
bad:
fdrop(fp, td);
if (error != 0 && *sa != NULL) {
free(*sa, M_SONAME);
*sa = NULL;
}
return (error);
}
int
sys_getsockname(struct thread *td, struct getsockname_args *uap)
{
return (getsockname1(td, uap, 0));
}
#ifdef COMPAT_OLDSOCK
int
ogetsockname(struct thread *td, struct getsockname_args *uap)
{
return (getsockname1(td, uap, 1));
}
#endif /* COMPAT_OLDSOCK */
/*
* getpeername1() - Get name of peer for connected socket.
*/
static int
getpeername1(struct thread *td, struct getpeername_args *uap, int compat)
{
struct sockaddr *sa;
socklen_t len;
int error;
error = copyin(uap->alen, &len, sizeof (len));
if (error != 0)
return (error);
error = kern_getpeername(td, uap->fdes, &sa, &len);
if (error != 0)
return (error);
if (len != 0) {
#ifdef COMPAT_OLDSOCK
if (compat && SV_PROC_FLAG(td->td_proc, SV_AOUT))
((struct osockaddr *)sa)->sa_family = sa->sa_family;
#endif
error = copyout(sa, uap->asa, (u_int)len);
}
free(sa, M_SONAME);
if (error == 0)
error = copyout(&len, uap->alen, sizeof(len));
return (error);
}
int
kern_getpeername(struct thread *td, int fd, struct sockaddr **sa,
socklen_t *alen)
{
struct socket *so;
struct file *fp;
socklen_t len;
int error;
AUDIT_ARG_FD(fd);
error = getsock_cap(td, fd, &cap_getpeername_rights,
&fp, NULL, NULL);
if (error != 0)
return (error);
so = fp->f_data;
if ((so->so_state & (SS_ISCONNECTED|SS_ISCONFIRMING)) == 0) {
error = ENOTCONN;
goto done;
}
*sa = NULL;
CURVNET_SET(so->so_vnet);
error = (*so->so_proto->pr_usrreqs->pru_peeraddr)(so, sa);
CURVNET_RESTORE();
if (error != 0)
goto bad;
if (*sa == NULL)
len = 0;
else
len = MIN(*alen, (*sa)->sa_len);
*alen = len;
#ifdef KTRACE
if (KTRPOINT(td, KTR_STRUCT))
ktrsockaddr(*sa);
#endif
bad:
if (error != 0 && *sa != NULL) {
free(*sa, M_SONAME);
*sa = NULL;
}
done:
fdrop(fp, td);
return (error);
}
int
sys_getpeername(struct thread *td, struct getpeername_args *uap)
{
return (getpeername1(td, uap, 0));
}
#ifdef COMPAT_OLDSOCK
int
ogetpeername(struct thread *td, struct ogetpeername_args *uap)
{
/* XXX uap should have type `getpeername_args *' to begin with. */
return (getpeername1(td, (struct getpeername_args *)uap, 1));
}
#endif /* COMPAT_OLDSOCK */
static int
sockargs(struct mbuf **mp, char *buf, socklen_t buflen, int type)
{
struct sockaddr *sa;
struct mbuf *m;
int error;
if (buflen > MLEN) {
#ifdef COMPAT_OLDSOCK
if (type == MT_SONAME && buflen <= 112 &&
SV_CURPROC_FLAG(SV_AOUT))
buflen = MLEN; /* unix domain compat. hack */
else
#endif
if (buflen > MCLBYTES)
return (EINVAL);
}
m = m_get2(buflen, M_WAITOK, type, 0);
m->m_len = buflen;
error = copyin(buf, mtod(m, void *), buflen);
if (error != 0)
(void) m_free(m);
else {
*mp = m;
if (type == MT_SONAME) {
sa = mtod(m, struct sockaddr *);
#if defined(COMPAT_OLDSOCK) && BYTE_ORDER != BIG_ENDIAN
if (sa->sa_family == 0 && sa->sa_len < AF_MAX &&
SV_CURPROC_FLAG(SV_AOUT))
sa->sa_family = sa->sa_len;
#endif
sa->sa_len = buflen;
}
}
return (error);
}
int
getsockaddr(struct sockaddr **namp, const struct sockaddr *uaddr, size_t len)
{
struct sockaddr *sa;
int error;
if (len > SOCK_MAXADDRLEN)
return (ENAMETOOLONG);
if (len < offsetof(struct sockaddr, sa_data[0]))
return (EINVAL);
sa = malloc(len, M_SONAME, M_WAITOK);
error = copyin(uaddr, sa, len);
if (error != 0) {
free(sa, M_SONAME);
} else {
#if defined(COMPAT_OLDSOCK) && BYTE_ORDER != BIG_ENDIAN
if (sa->sa_family == 0 && sa->sa_len < AF_MAX &&
SV_CURPROC_FLAG(SV_AOUT))
sa->sa_family = sa->sa_len;
#endif
sa->sa_len = len;
*namp = sa;
}
return (error);
}
/*
* Dispose of externalized rights from an SCM_RIGHTS message. This function
* should be used in error or truncation cases to avoid leaking file descriptors
* into the recipient's (the current thread's) table.
*/
void
m_dispose_extcontrolm(struct mbuf *m)
{
struct cmsghdr *cm;
struct file *fp;
struct thread *td;
socklen_t clen, datalen;
int error, fd, *fds, nfd;
td = curthread;
for (; m != NULL; m = m->m_next) {
if (m->m_type != MT_EXTCONTROL)
continue;
cm = mtod(m, struct cmsghdr *);
clen = m->m_len;
while (clen > 0) {
if (clen < sizeof(*cm))
panic("%s: truncated mbuf %p", __func__, m);
datalen = CMSG_SPACE(cm->cmsg_len - CMSG_SPACE(0));
if (clen < datalen)
panic("%s: truncated mbuf %p", __func__, m);
if (cm->cmsg_level == SOL_SOCKET &&
cm->cmsg_type == SCM_RIGHTS) {
fds = (int *)CMSG_DATA(cm);
nfd = (cm->cmsg_len - CMSG_SPACE(0)) /
sizeof(int);
while (nfd-- > 0) {
fd = *fds++;
error = fget(td, fd, &cap_no_rights,
&fp);
if (error == 0) {
fdclose(td, fp, fd);
fdrop(fp, td);
}
}
}
clen -= datalen;
cm = (struct cmsghdr *)((uint8_t *)cm + datalen);
}
m_chtype(m, MT_CONTROL);
}
}