388 lines
8.4 KiB
C
388 lines
8.4 KiB
C
/* $NetBSD: tty_ptm.c,v 1.26 2009/01/22 14:38:35 yamt Exp $ */
|
|
|
|
/*-
|
|
* Copyright (c) 2004 The NetBSD Foundation, Inc.
|
|
* 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.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__KERNEL_RCSID(0, "$NetBSD: tty_ptm.c,v 1.26 2009/01/22 14:38:35 yamt Exp $");
|
|
|
|
#include "opt_ptm.h"
|
|
|
|
/* pty multiplexor driver /dev/ptm{,x} */
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/ioctl.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/tty.h>
|
|
#include <sys/stat.h>
|
|
#include <sys/file.h>
|
|
#include <sys/uio.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/vnode.h>
|
|
#include <sys/namei.h>
|
|
#include <sys/signalvar.h>
|
|
#include <sys/filedesc.h>
|
|
#include <sys/conf.h>
|
|
#include <sys/poll.h>
|
|
#include <sys/pty.h>
|
|
#include <sys/kauth.h>
|
|
|
|
#include <miscfs/specfs/specdev.h>
|
|
|
|
#ifdef DEBUG_PTM
|
|
#define DPRINTF(a) printf a
|
|
#else
|
|
#define DPRINTF(a)
|
|
#endif
|
|
|
|
#ifdef NO_DEV_PTM
|
|
const struct cdevsw ptm_cdevsw = {
|
|
noopen, noclose, noread, nowrite, noioctl,
|
|
nostop, notty, nopoll, nommap, nokqfilter, D_TTY
|
|
};
|
|
#else
|
|
|
|
static struct ptm_pty *ptm;
|
|
int pts_major, ptc_major;
|
|
|
|
static dev_t pty_getfree(void);
|
|
static int pty_alloc_master(struct lwp *, int *, dev_t *);
|
|
static int pty_alloc_slave(struct lwp *, int *, dev_t);
|
|
|
|
void ptmattach(int);
|
|
|
|
dev_t
|
|
pty_makedev(char ms, int minor)
|
|
{
|
|
return makedev(ms == 't' ? pts_major : ptc_major, minor);
|
|
}
|
|
|
|
|
|
static dev_t
|
|
pty_getfree(void)
|
|
{
|
|
extern kmutex_t pt_softc_mutex;
|
|
int i;
|
|
|
|
mutex_enter(&pt_softc_mutex);
|
|
for (i = 0; i < npty; i++) {
|
|
if (pty_isfree(i, 0))
|
|
break;
|
|
}
|
|
mutex_exit(&pt_softc_mutex);
|
|
return pty_makedev('t', i);
|
|
}
|
|
|
|
/*
|
|
* Hacked up version of vn_open. We _only_ handle ptys and only open
|
|
* them with FREAD|FWRITE and never deal with creat or stuff like that.
|
|
*
|
|
* We need it because we have to fake up root credentials to open the pty.
|
|
*/
|
|
int
|
|
pty_vn_open(struct vnode *vp, struct lwp *l)
|
|
{
|
|
int error;
|
|
|
|
if (vp->v_type != VCHR) {
|
|
vput(vp);
|
|
return EINVAL;
|
|
}
|
|
|
|
error = VOP_OPEN(vp, FREAD|FWRITE, lwp0.l_cred);
|
|
|
|
if (error) {
|
|
vput(vp);
|
|
return error;
|
|
}
|
|
|
|
vp->v_writecount++;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
pty_alloc_master(struct lwp *l, int *fd, dev_t *dev)
|
|
{
|
|
int error;
|
|
struct file *fp;
|
|
struct vnode *vp;
|
|
int md;
|
|
|
|
if ((error = fd_allocfile(&fp, fd)) != 0) {
|
|
DPRINTF(("fd_allocfile %d\n", error));
|
|
return error;
|
|
}
|
|
retry:
|
|
/* Find and open a free master pty. */
|
|
*dev = pty_getfree();
|
|
md = minor(*dev);
|
|
if ((error = pty_check(md)) != 0) {
|
|
DPRINTF(("pty_check %d\n", error));
|
|
goto bad;
|
|
}
|
|
if (ptm == NULL) {
|
|
DPRINTF(("no ptm\n"));
|
|
error = EOPNOTSUPP;
|
|
goto bad;
|
|
}
|
|
if ((error = (*ptm->allocvp)(ptm, l, &vp, *dev, 'p')) != 0) {
|
|
DPRINTF(("pty_allocvp %d\n", error));
|
|
goto bad;
|
|
}
|
|
|
|
if ((error = pty_vn_open(vp, l)) != 0) {
|
|
DPRINTF(("pty_vn_open %d\n", error));
|
|
/*
|
|
* Check if the master open failed because we lost
|
|
* the race to grab it.
|
|
*/
|
|
if (error != EIO)
|
|
goto bad;
|
|
error = !pty_isfree(md, 1);
|
|
DPRINTF(("pty_isfree %d\n", error));
|
|
if (error)
|
|
goto retry;
|
|
else
|
|
goto bad;
|
|
}
|
|
fp->f_flag = FREAD|FWRITE;
|
|
fp->f_type = DTYPE_VNODE;
|
|
fp->f_ops = &vnops;
|
|
fp->f_data = vp;
|
|
VOP_UNLOCK(vp, 0);
|
|
fd_affix(curproc, fp, *fd);
|
|
return 0;
|
|
bad:
|
|
fd_abort(curproc, fp, *fd);
|
|
return error;
|
|
}
|
|
|
|
int
|
|
pty_grant_slave(struct lwp *l, dev_t dev)
|
|
{
|
|
int error;
|
|
struct vnode *vp;
|
|
|
|
/*
|
|
* Open the slave.
|
|
* namei -> setattr -> unlock -> revoke -> vrele ->
|
|
* namei -> open -> unlock
|
|
* Three stage rocket:
|
|
* 1. Change the owner and permissions on the slave.
|
|
* 2. Revoke all the users of the slave.
|
|
* 3. open the slave.
|
|
*/
|
|
if (ptm == NULL)
|
|
return EOPNOTSUPP;
|
|
if ((error = (*ptm->allocvp)(ptm, l, &vp, dev, 't')) != 0)
|
|
return error;
|
|
|
|
if ((vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
|
|
struct vattr vattr;
|
|
(*ptm->getvattr)(ptm, l, &vattr);
|
|
/* Do the VOP_SETATTR() as root. */
|
|
error = VOP_SETATTR(vp, &vattr, lwp0.l_cred);
|
|
if (error) {
|
|
DPRINTF(("setattr %d\n", error));
|
|
VOP_UNLOCK(vp, 0);
|
|
vrele(vp);
|
|
return error;
|
|
}
|
|
}
|
|
VOP_UNLOCK(vp, 0);
|
|
VOP_REVOKE(vp, REVOKEALL);
|
|
|
|
/*
|
|
* The vnode is useless after the revoke, we need to get it again.
|
|
*/
|
|
vrele(vp);
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
pty_alloc_slave(struct lwp *l, int *fd, dev_t dev)
|
|
{
|
|
int error;
|
|
struct file *fp;
|
|
struct vnode *vp;
|
|
|
|
/* Grab a filedescriptor for the slave */
|
|
if ((error = fd_allocfile(&fp, fd)) != 0) {
|
|
DPRINTF(("fd_allocfile %d\n", error));
|
|
return error;
|
|
}
|
|
|
|
if (ptm == NULL) {
|
|
error = EOPNOTSUPP;
|
|
goto bad;
|
|
}
|
|
|
|
if ((error = (*ptm->allocvp)(ptm, l, &vp, dev, 't')) != 0)
|
|
goto bad;
|
|
if ((error = pty_vn_open(vp, l)) != 0)
|
|
goto bad;
|
|
|
|
fp->f_flag = FREAD|FWRITE;
|
|
fp->f_type = DTYPE_VNODE;
|
|
fp->f_ops = &vnops;
|
|
fp->f_data = vp;
|
|
VOP_UNLOCK(vp, 0);
|
|
fd_affix(curproc, fp, *fd);
|
|
return 0;
|
|
bad:
|
|
fd_abort(curproc, fp, *fd);
|
|
return error;
|
|
}
|
|
|
|
struct ptm_pty *
|
|
pty_sethandler(struct ptm_pty *nptm)
|
|
{
|
|
struct ptm_pty *optm = ptm;
|
|
ptm = nptm;
|
|
return optm;
|
|
}
|
|
|
|
int
|
|
pty_fill_ptmget(struct lwp *l, dev_t dev, int cfd, int sfd, void *data)
|
|
{
|
|
struct ptmget *ptmg = data;
|
|
int error;
|
|
|
|
if (ptm == NULL)
|
|
return EOPNOTSUPP;
|
|
|
|
ptmg->cfd = cfd == -1 ? minor(dev) : cfd;
|
|
ptmg->sfd = sfd == -1 ? minor(dev) : sfd;
|
|
|
|
error = (*ptm->makename)(ptm, l, ptmg->cn, sizeof(ptmg->cn), dev, 'p');
|
|
if (error)
|
|
return error;
|
|
|
|
return (*ptm->makename)(ptm, l, ptmg->sn, sizeof(ptmg->sn), dev, 't');
|
|
}
|
|
|
|
void
|
|
/*ARGSUSED*/
|
|
ptmattach(int n)
|
|
{
|
|
extern const struct cdevsw pts_cdevsw, ptc_cdevsw;
|
|
/* find the major and minor of the pty devices */
|
|
if ((pts_major = cdevsw_lookup_major(&pts_cdevsw)) == -1)
|
|
panic("ptmattach: Can't find pty slave in cdevsw");
|
|
if ((ptc_major = cdevsw_lookup_major(&ptc_cdevsw)) == -1)
|
|
panic("ptmattach: Can't find pty master in cdevsw");
|
|
#ifdef COMPAT_BSDPTY
|
|
ptm = &ptm_bsdpty;
|
|
#endif
|
|
}
|
|
|
|
static int
|
|
/*ARGSUSED*/
|
|
ptmopen(dev_t dev, int flag, int mode, struct lwp *l)
|
|
{
|
|
int error;
|
|
int fd;
|
|
dev_t ttydev;
|
|
|
|
switch(minor(dev)) {
|
|
case 0: /* /dev/ptmx */
|
|
case 2: /* /emul/linux/dev/ptmx */
|
|
if ((error = pty_alloc_master(l, &fd, &ttydev)) != 0)
|
|
return error;
|
|
if (minor(dev) == 2) {
|
|
/*
|
|
* Linux ptyfs grants the pty right here.
|
|
* Handle this case here, instead of writing
|
|
* a new linux module.
|
|
*/
|
|
if ((error = pty_grant_slave(l, ttydev)) != 0) {
|
|
file_t *fp = fd_getfile(fd);
|
|
if (fp != NULL) {
|
|
fd_close(fd);
|
|
}
|
|
return error;
|
|
}
|
|
}
|
|
curlwp->l_dupfd = fd;
|
|
return EMOVEFD;
|
|
case 1: /* /dev/ptm */
|
|
return 0;
|
|
default:
|
|
return ENODEV;
|
|
}
|
|
}
|
|
|
|
static int
|
|
/*ARGSUSED*/
|
|
ptmclose(dev_t dev, int flag, int mode, struct lwp *l)
|
|
{
|
|
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
/*ARGSUSED*/
|
|
ptmioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
|
|
{
|
|
int error;
|
|
dev_t newdev;
|
|
int cfd, sfd;
|
|
file_t *fp;
|
|
|
|
error = 0;
|
|
switch (cmd) {
|
|
case TIOCPTMGET:
|
|
if ((error = pty_alloc_master(l, &cfd, &newdev)) != 0)
|
|
return error;
|
|
|
|
if ((error = pty_grant_slave(l, newdev)) != 0)
|
|
goto bad;
|
|
|
|
if ((error = pty_alloc_slave(l, &sfd, newdev)) != 0)
|
|
goto bad;
|
|
|
|
/* now, put the indices and names into struct ptmget */
|
|
return pty_fill_ptmget(l, newdev, cfd, sfd, data);
|
|
default:
|
|
DPRINTF(("ptmioctl EINVAL\n"));
|
|
return EINVAL;
|
|
}
|
|
bad:
|
|
fp = fd_getfile(cfd);
|
|
if (fp != NULL) {
|
|
fd_close(cfd);
|
|
}
|
|
return error;
|
|
}
|
|
|
|
const struct cdevsw ptm_cdevsw = {
|
|
ptmopen, ptmclose, noread, nowrite, ptmioctl,
|
|
nullstop, notty, nopoll, nommap, nokqfilter, D_TTY
|
|
};
|
|
#endif
|