/*
* Open a special file.
*/
int
spec_open(void *v)
{
struct vop_open_args *ap = v;
struct proc *p = ap->a_p;
struct vnode *vp = ap->a_vp;
struct vnode *bvp;
dev_t bdev;
dev_t dev = (dev_t)vp->v_rdev;
int maj = major(dev);
int error;
/*
* Don't allow open if fs is mounted -nodev.
*/
if (vp->v_mount && (vp->v_mount->mnt_flag & MNT_NODEV))
return (ENXIO);
switch (vp->v_type) {
case VCHR:
if ((u_int)maj >= nchrdev)
return (ENXIO);
if (ap->a_cred != FSCRED && (ap->a_mode & FWRITE)) {
/*
* When running in very secure mode, do not allow
* opens for writing of any disk character devices.
*/
if (securelevel >= 2 && cdevsw[maj].d_type == D_DISK)
return (EPERM);
/*
* When running in secure mode, do not allow opens
* for writing of /dev/mem, /dev/kmem, or character
* devices whose corresponding block devices are
* currently mounted.
*/
if (securelevel >= 1) {
if ((bdev = chrtoblk(dev)) != NODEV &&
vfinddev(bdev, VBLK, &bvp) &&
bvp->v_usecount > 0 &&
(error = vfs_mountedon(bvp)))
return (error);
if (iskmemdev(dev))
return (EPERM);
}
}
if (cdevsw[maj].d_type == D_TTY)
vp->v_flag |= VISTTY;
if (cdevsw[maj].d_flags & D_CLONE)
return (spec_open_clone(ap));
VOP_UNLOCK(vp, 0, p);
error = (*cdevsw[maj].d_open)(dev, ap->a_mode, S_IFCHR, p);
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
return (error);
case VBLK:
if ((u_int)maj >= nblkdev)
return (ENXIO);
/*
* When running in very secure mode, do not allow
* opens for writing of any disk block devices.
*/
if (securelevel >= 2 && ap->a_cred != FSCRED &&
(ap->a_mode & FWRITE) && bdevsw[maj].d_type == D_DISK)
return (EPERM);
/*
* Do not allow opens of block devices that are
* currently mounted.
*/
if ((error = vfs_mountedon(vp)) != 0)
return (error);
return ((*bdevsw[maj].d_open)(dev, ap->a_mode, S_IFBLK, p));
case VNON:
case VLNK:
case VDIR:
case VREG:
case VBAD:
case VFIFO:
case VSOCK:
break;
}
return (0);
}
/*
* Open a special file.
*/
int
spec_open(struct vnop_open_args *ap)
{
struct proc *p = vfs_context_proc(ap->a_context);
kauth_cred_t cred = vfs_context_ucred(ap->a_context);
struct vnode *vp = ap->a_vp;
dev_t bdev, dev = (dev_t)vp->v_rdev;
int maj = major(dev);
int error;
/*
* Don't allow open if fs is mounted -nodev.
*/
if (vp->v_mount && (vp->v_mount->mnt_flag & MNT_NODEV))
return (ENXIO);
switch (vp->v_type) {
case VCHR:
if ((u_int)maj >= (u_int)nchrdev)
return (ENXIO);
if (cred != FSCRED && (ap->a_mode & FWRITE)) {
/*
* When running in very secure mode, do not allow
* opens for writing of any disk character devices.
*/
if (securelevel >= 2 && isdisk(dev, VCHR))
return (EPERM);
/*
* When running in secure mode, do not allow opens
* for writing of /dev/mem, /dev/kmem, or character
* devices whose corresponding block devices are
* currently mounted.
*/
if (securelevel >= 1) {
if ((bdev = chrtoblk(dev)) != NODEV && check_mountedon(bdev, VBLK, &error))
return (error);
if (iskmemdev(dev))
return (EPERM);
}
}
if (cdevsw[maj].d_type == D_TTY) {
vnode_lock(vp);
vp->v_flag |= VISTTY;
vnode_unlock(vp);
}
error = (*cdevsw[maj].d_open)(dev, ap->a_mode, S_IFCHR, p);
return (error);
case VBLK:
if ((u_int)maj >= (u_int)nblkdev)
return (ENXIO);
/*
* When running in very secure mode, do not allow
* opens for writing of any disk block devices.
*/
if (securelevel >= 2 && cred != FSCRED &&
(ap->a_mode & FWRITE) && bdevsw[maj].d_type == D_DISK)
return (EPERM);
/*
* Do not allow opens of block devices that are
* currently mounted.
*/
if ( (error = vfs_mountedon(vp)) )
return (error);
error = (*bdevsw[maj].d_open)(dev, ap->a_mode, S_IFBLK, p);
if (!error) {
u_int64_t blkcnt;
u_int32_t blksize;
int setsize = 0;
u_int32_t size512 = 512;
if (!VNOP_IOCTL(vp, DKIOCGETBLOCKSIZE, (caddr_t)&blksize, 0, ap->a_context)) {
/* Switch to 512 byte sectors (temporarily) */
if (!VNOP_IOCTL(vp, DKIOCSETBLOCKSIZE, (caddr_t)&size512, FWRITE, ap->a_context)) {
/* Get the number of 512 byte physical blocks. */
if (!VNOP_IOCTL(vp, DKIOCGETBLOCKCOUNT, (caddr_t)&blkcnt, 0, ap->a_context)) {
setsize = 1;
}
}
/* If it doesn't set back, we can't recover */
if (VNOP_IOCTL(vp, DKIOCSETBLOCKSIZE, (caddr_t)&blksize, FWRITE, ap->a_context))
error = ENXIO;
}
vnode_lock(vp);
set_blocksize(vp, dev);
/*
* Cache the size in bytes of the block device for later
* use by spec_write().
*/
if (setsize)
vp->v_specdevsize = blkcnt * (u_int64_t)size512;
else
vp->v_specdevsize = (u_int64_t)0; /* Default: Can't get */
vnode_unlock(vp);
}
return(error);
default:
panic("spec_open type");
}
return (0);
}
