/*-
* Copyright (c) 1982, 1986, 1991, 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 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.
*
* @(#)tty_tty.c 8.2 (Berkeley) 9/23/93
* $FreeBSD$
*/
/*
* Indirect driver for controlling tty.
*/
#include "opt_mac.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/conf.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/mac.h>
#include <sys/mutex.h>
#include <sys/sx.h>
#include <sys/proc.h>
#include <sys/ttycom.h>
#include <sys/vnode.h>
static d_open_t cttyopen;
static d_read_t cttyread;
static d_write_t cttywrite;
static d_ioctl_t cttyioctl;
static d_poll_t cttypoll;
#define CDEV_MAJOR 1
static struct cdevsw ctty_cdevsw = {
/* open */ cttyopen,
/* close */ nullclose,
/* read */ cttyread,
/* write */ cttywrite,
/* ioctl */ cttyioctl,
/* poll */ cttypoll,
/* mmap */ nommap,
/* strategy */ nostrategy,
/* name */ "ctty",
/* maj */ CDEV_MAJOR,
/* dump */ nodump,
/* psize */ nopsize,
/* flags */ D_TTY,
};
#define cttyvp(td) ((td)->td_proc->p_flag & P_CONTROLT ? (td)->td_proc->p_session->s_ttyvp : NULL)
/*ARGSUSED*/
static int
cttyopen(dev, flag, mode, td)
dev_t dev;
int flag, mode;
struct thread *td;
{
struct vnode *ttyvp;
int error;
PROC_LOCK(td->td_proc);
SESS_LOCK(td->td_proc->p_session);
ttyvp = cttyvp(td);
SESS_UNLOCK(td->td_proc->p_session);
PROC_UNLOCK(td->td_proc);
if (ttyvp == NULL)
return (ENXIO);
vn_lock(ttyvp, LK_EXCLUSIVE | LK_RETRY, td);
#ifdef MAC
error = mac_check_vnode_open(td->td_ucred, ttyvp, flag);
if (error) {
VOP_UNLOCK(ttyvp, 0, td);
return (error);
}
#endif
/* XXX: Shouldn't this cred be td->td_ucred not NOCRED? */
error = VOP_OPEN(ttyvp, flag, NOCRED, td);
VOP_UNLOCK(ttyvp, 0, td);
return (error);
}
/*ARGSUSED*/
static int
cttyread(dev, uio, flag)
dev_t dev;
struct uio *uio;
int flag;
{
struct thread *td = uio->uio_td;
register struct vnode *ttyvp;
int error;
PROC_LOCK(td->td_proc);
SESS_LOCK(td->td_proc->p_session);
ttyvp = cttyvp(td);
SESS_UNLOCK(td->td_proc->p_session);
PROC_UNLOCK(td->td_proc);
if (ttyvp == NULL)
return (EIO);
vn_lock(ttyvp, LK_EXCLUSIVE | LK_RETRY, td);
#ifdef MAC
error = mac_check_vnode_read(td->td_ucred, NOCRED, ttyvp);
if (error == 0)
#endif
/* XXX: Shouldn't this cred be td->td_ucred not NOCRED? */
error = VOP_READ(ttyvp, uio, flag, NOCRED);
VOP_UNLOCK(ttyvp, 0, td);
return (error);
}
/*ARGSUSED*/
static int
cttywrite(dev, uio, flag)
dev_t dev;
struct uio *uio;
int flag;
{
struct thread *td = uio->uio_td;
struct vnode *ttyvp;
struct mount *mp;
int error;
PROC_LOCK(td->td_proc);
SESS_LOCK(td->td_proc->p_session);
ttyvp = cttyvp(td);
SESS_UNLOCK(td->td_proc->p_session);
PROC_UNLOCK(td->td_proc);
if (ttyvp == NULL)
return (EIO);
mp = NULL;
if (ttyvp->v_type != VCHR &&
(error = vn_start_write(ttyvp, &mp, V_WAIT | PCATCH)) != 0)
return (error);
vn_lock(ttyvp, LK_EXCLUSIVE | LK_RETRY, td);
#ifdef MAC
error = mac_check_vnode_write(td->td_ucred, NOCRED, ttyvp);
if (error == 0)
#endif
/* XXX: shouldn't this cred be td->td_ucred not NOCRED? */
error = VOP_WRITE(ttyvp, uio, flag, NOCRED);
VOP_UNLOCK(ttyvp, 0, td);
vn_finished_write(mp);
return (error);
}
/*ARGSUSED*/
static int
cttyioctl(dev, cmd, addr, flag, td)
dev_t dev;
u_long cmd;
caddr_t addr;
int flag;
struct thread *td;
{
struct vnode *ttyvp;
int error;
PROC_LOCK(td->td_proc);
SESS_LOCK(td->td_proc->p_session);
ttyvp = cttyvp(td);
SESS_UNLOCK(td->td_proc->p_session);
PROC_UNLOCK(td->td_proc);
if (ttyvp == NULL)
return (EIO);
if (cmd == TIOCSCTTY) /* don't allow controlling tty to be set */
return EINVAL; /* to controlling tty -- infinite recursion */
if (cmd == TIOCNOTTY) {
PROC_LOCK(td->td_proc);
SESS_LOCK(td->td_proc->p_session);
error = 0;
if (!SESS_LEADER(td->td_proc))
td->td_proc->p_flag &= ~P_CONTROLT;
else
error = EINVAL;
SESS_UNLOCK(td->td_proc->p_session);
PROC_UNLOCK(td->td_proc);
return (error);
}
/* XXXMAC: Should this be td->td_ucred below? */
return (VOP_IOCTL(ttyvp, cmd, addr, flag, NOCRED, td));
}
/*ARGSUSED*/
static int
cttypoll(dev, events, td)
dev_t dev;
int events;
struct thread *td;
{
struct vnode *ttyvp;
#ifdef MAC
int error;
#endif
PROC_LOCK(td->td_proc);
SESS_LOCK(td->td_proc->p_session);
ttyvp = cttyvp(td);
SESS_UNLOCK(td->td_proc->p_session);
PROC_UNLOCK(td->td_proc);
if (ttyvp == NULL)
/* try operation to get EOF/failure */
return (seltrue(dev, events, td));
#ifdef MAC
vn_lock(ttyvp, LK_EXCLUSIVE | LK_RETRY, td);
error = mac_check_vnode_poll(td->td_ucred, NOCRED, ttyvp);
VOP_UNLOCK(ttyvp, 0, td);
if (error)
return (error);
#endif
return (VOP_POLL(ttyvp, events, td->td_ucred, td));
}
static void ctty_clone(void *arg, char *name, int namelen, dev_t *dev);
static dev_t ctty;
static void
ctty_clone(void *arg, char *name, int namelen, dev_t *dev)
{
struct vnode *vp;
if (*dev != NODEV)
return;
if (strcmp(name, "tty"))
return;
vp = cttyvp(curthread);
if (vp == NULL) {
if (ctty)
*dev = ctty;
} else
*dev = vp->v_rdev;
}
static void ctty_drvinit(void *unused);
static void
ctty_drvinit(unused)
void *unused;
{
if (devfs_present) {
EVENTHANDLER_REGISTER(dev_clone, ctty_clone, 0, 1000);
ctty = make_dev(&ctty_cdevsw, 0, 0, 0, 0666, "ctty");
} else {
make_dev(&ctty_cdevsw, 0, 0, 0, 0666, "tty");
}
}
SYSINIT(cttydev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,ctty_drvinit,NULL)
