freebsd-nq/sys/kern/sys_socket.c
Robert Watson c0b99ffa02 The socket field so_state is used to hold a variety of socket related
flags relating to several aspects of socket functionality.  This change
breaks out several bits relating to send and receive operation into a
new per-socket buffer field, sb_state, in order to facilitate locking.
This is required because, in order to provide more granular locking of
sockets, different state fields have different locking properties.  The
following fields are moved to sb_state:

  SS_CANTRCVMORE            (so_state)
  SS_CANTSENDMORE           (so_state)
  SS_RCVATMARK              (so_state)

Rename respectively to:

  SBS_CANTRCVMORE           (so_rcv.sb_state)
  SBS_CANTSENDMORE          (so_snd.sb_state)
  SBS_RCVATMARK             (so_rcv.sb_state)

This facilitates locking by isolating fields to be located with other
identically locked fields, and permits greater granularity in socket
locking by avoiding storing fields with different locking semantics in
the same short (avoiding locking conflicts).  In the future, we may
wish to coallesce sb_state and sb_flags; for the time being I leave
them separate and there is no additional memory overhead due to the
packing/alignment of shorts in the socket buffer structure.
2004-06-14 18:16:22 +00:00

247 lines
6.1 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:
if (*(int *)data)
so->so_state |= SS_NBIO;
else
so->so_state &= ~SS_NBIO;
return (0);
case FIOASYNC:
if (*(int *)data) {
so->so_state |= SS_ASYNC;
so->so_rcv.sb_flags |= SB_ASYNC;
so->so_snd.sb_flags |= SB_ASYNC;
} else {
so->so_state &= ~SS_ASYNC;
so->so_rcv.sb_flags &= ~SB_ASYNC;
so->so_snd.sb_flags &= ~SB_ASYNC;
}
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);
}