freebsd-dev/sys/kern/sys_socket.c
Robert Watson 9535efc00d Merge additional socket buffer locking from rwatson_netperf:
- Lock down low hanging fruit use of sb_flags with socket buffer
  lock.

- Lock down low hanging fruit use of so_state with socket lock.

- Lock down low hanging fruit use of so_options.

- Lock down low-hanging fruit use of sb_lowwat and sb_hiwat with
  socket buffer lock.

- Annotate situations in which we unlock the socket lock and then
  grab the receive socket buffer lock, which are currently actually
  the same lock.  Depending on how we want to play our cards, we
  may want to coallesce these lock uses to reduce overhead.

- Convert a if()->panic() into a KASSERT relating to so_state in
  soaccept().

- Remove a number of splnet()/splx() references.

More complex merging of socket and socket buffer locking to
follow.
2004-06-17 22:48:11 +00:00

267 lines
6.6 KiB
C

/*
* Copyright (c) 1982, 1986, 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.
* 4. 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.
*
* @(#)sys_socket.c 8.1 (Berkeley) 6/10/93
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_mac.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/file.h>
#include <sys/filedesc.h>
#include <sys/mac.h>
#include <sys/protosw.h>
#include <sys/sigio.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/filio.h> /* XXX */
#include <sys/sockio.h>
#include <sys/stat.h>
#include <sys/uio.h>
#include <sys/ucred.h>
#include <net/if.h>
#include <net/route.h>
struct fileops socketops = {
.fo_read = soo_read,
.fo_write = soo_write,
.fo_ioctl = soo_ioctl,
.fo_poll = soo_poll,
.fo_kqfilter = soo_kqfilter,
.fo_stat = soo_stat,
.fo_close = soo_close,
.fo_flags = DFLAG_PASSABLE
};
/* ARGSUSED */
int
soo_read(fp, uio, active_cred, flags, td)
struct file *fp;
struct uio *uio;
struct ucred *active_cred;
struct thread *td;
int flags;
{
struct socket *so = fp->f_data;
int error;
NET_LOCK_GIANT();
#ifdef MAC
SOCK_LOCK(so);
error = mac_check_socket_receive(active_cred, so);
SOCK_UNLOCK(so);
if (error) {
NET_UNLOCK_GIANT();
return (error);
}
#endif
error = so->so_proto->pr_usrreqs->pru_soreceive(so, 0, uio, 0, 0, 0);
NET_UNLOCK_GIANT();
return (error);
}
/* ARGSUSED */
int
soo_write(fp, uio, active_cred, flags, td)
struct file *fp;
struct uio *uio;
struct ucred *active_cred;
struct thread *td;
int flags;
{
struct socket *so = fp->f_data;
int error;
NET_LOCK_GIANT();
#ifdef MAC
SOCK_LOCK(so);
error = mac_check_socket_send(active_cred, so);
SOCK_UNLOCK(so);
if (error) {
NET_UNLOCK_GIANT();
return (error);
}
#endif
error = so->so_proto->pr_usrreqs->pru_sosend(so, 0, uio, 0, 0, 0,
uio->uio_td);
NET_UNLOCK_GIANT();
return (error);
}
int
soo_ioctl(fp, cmd, data, active_cred, td)
struct file *fp;
u_long cmd;
void *data;
struct ucred *active_cred;
struct thread *td;
{
register struct socket *so = fp->f_data;
switch (cmd) {
case FIONBIO:
SOCK_LOCK(so);
if (*(int *)data)
so->so_state |= SS_NBIO;
else
so->so_state &= ~SS_NBIO;
SOCK_UNLOCK(so);
return (0);
case FIOASYNC:
/*
* XXXRW: This code separately acquires SOCK_LOCK(so)
* and SOCKBUF_LOCK(&so->so_rcv) even though they are
* the same mutex to avoid introducing the assumption
* that they are the same.
*/
if (*(int *)data) {
SOCK_LOCK(so);
so->so_state |= SS_ASYNC;
SOCK_UNLOCK(so);
SOCKBUF_LOCK(&so->so_rcv);
so->so_rcv.sb_flags |= SB_ASYNC;
SOCKBUF_UNLOCK(&so->so_rcv);
SOCKBUF_LOCK(&so->so_snd);
so->so_snd.sb_flags |= SB_ASYNC;
SOCKBUF_UNLOCK(&so->so_snd);
} else {
SOCK_LOCK(so);
so->so_state &= ~SS_ASYNC;
SOCK_UNLOCK(so);
SOCKBUF_LOCK(&so->so_rcv);
so->so_rcv.sb_flags &= ~SB_ASYNC;
SOCKBUF_UNLOCK(&so->so_rcv);
SOCKBUF_LOCK(&so->so_snd);
so->so_snd.sb_flags &= ~SB_ASYNC;
SOCKBUF_UNLOCK(&so->so_snd);
}
return (0);
case FIONREAD:
*(int *)data = so->so_rcv.sb_cc;
return (0);
case FIOSETOWN:
return (fsetown(*(int *)data, &so->so_sigio));
case FIOGETOWN:
*(int *)data = fgetown(&so->so_sigio);
return (0);
case SIOCSPGRP:
return (fsetown(-(*(int *)data), &so->so_sigio));
case SIOCGPGRP:
*(int *)data = -fgetown(&so->so_sigio);
return (0);
case SIOCATMARK:
*(int *)data = (so->so_rcv.sb_state & SBS_RCVATMARK) != 0;
return (0);
}
/*
* Interface/routing/protocol specific ioctls:
* interface and routing ioctls should have a
* different entry since a socket's unnecessary
*/
if (IOCGROUP(cmd) == 'i')
return (ifioctl(so, cmd, data, td));
if (IOCGROUP(cmd) == 'r')
return (rtioctl(cmd, data));
return ((*so->so_proto->pr_usrreqs->pru_control)(so, cmd, data, 0, td));
}
int
soo_poll(fp, events, active_cred, td)
struct file *fp;
int events;
struct ucred *active_cred;
struct thread *td;
{
struct socket *so = fp->f_data;
return so->so_proto->pr_usrreqs->pru_sopoll(so, events,
fp->f_cred, td);
}
int
soo_stat(fp, ub, active_cred, td)
struct file *fp;
struct stat *ub;
struct ucred *active_cred;
struct thread *td;
{
struct socket *so = fp->f_data;
bzero((caddr_t)ub, sizeof (*ub));
ub->st_mode = S_IFSOCK;
/*
* If SBS_CANTRCVMORE is set, but there's still data left in the
* receive buffer, the socket is still readable.
*/
if ((so->so_rcv.sb_state & SBS_CANTRCVMORE) == 0 ||
so->so_rcv.sb_cc != 0)
ub->st_mode |= S_IRUSR | S_IRGRP | S_IROTH;
if ((so->so_snd.sb_state & SBS_CANTSENDMORE) == 0)
ub->st_mode |= S_IWUSR | S_IWGRP | S_IWOTH;
ub->st_size = so->so_rcv.sb_cc - so->so_rcv.sb_ctl;
ub->st_uid = so->so_cred->cr_uid;
ub->st_gid = so->so_cred->cr_gid;
return ((*so->so_proto->pr_usrreqs->pru_sense)(so, ub));
}
/*
* API socket close on file pointer. We call soclose() to close the
* socket (including initiating closing protocols). soclose() will
* sorele() the file reference but the actual socket will not go away
* until the socket's ref count hits 0.
*/
/* ARGSUSED */
int
soo_close(fp, td)
struct file *fp;
struct thread *td;
{
int error = 0;
struct socket *so;
so = fp->f_data;
fp->f_ops = &badfileops;
fp->f_data = NULL;
if (so)
error = soclose(so);
return (error);
}