/* $OpenBSD: tty_tty.c,v 1.6 1997/11/06 05:58:24 csapuntz Exp $ */ /* $NetBSD: tty_tty.c,v 1.13 1996/03/30 22:24:46 christos Exp $ */ /*- * 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 */ /* * Indirect driver for controlling tty. */ #include <sys/param.h> #include <sys/systm.h> #include <sys/ioctl.h> #include <sys/proc.h> #include <sys/tty.h> #include <sys/vnode.h> #include <sys/file.h> #include <sys/conf.h> #define cttyvp(p) ((p)->p_flag & P_CONTROLT ? (p)->p_session->s_ttyvp : NULL) /*ARGSUSED*/ int cttyopen(dev, flag, mode, p) dev_t dev; int flag, mode; struct proc *p; { struct vnode *ttyvp = cttyvp(p); int error; if (ttyvp == NULL) return (ENXIO); vn_lock(ttyvp, LK_EXCLUSIVE | LK_RETRY, p); #ifdef PARANOID /* * Since group is tty and mode is 620 on most terminal lines * and since sessions protect terminals from processes outside * your session, this check is probably no longer necessary. * Since it inhibits setuid root programs that later switch * to another user from accessing /dev/tty, we have decided * to delete this test. (mckusick 5/93) */ error = VOP_ACCESS(ttyvp, (flag&FREAD ? VREAD : 0) | (flag&FWRITE ? VWRITE : 0), p->p_ucred, p); if (!error) #endif /* PARANOID */ error = VOP_OPEN(ttyvp, flag, NOCRED, p); VOP_UNLOCK(ttyvp, 0, p); return (error); } /*ARGSUSED*/ int cttyread(dev, uio, flag) dev_t dev; struct uio *uio; int flag; { struct proc *p = uio->uio_procp; register struct vnode *ttyvp = cttyvp(uio->uio_procp); int error; if (ttyvp == NULL) return (EIO); vn_lock(ttyvp, LK_EXCLUSIVE | LK_RETRY, p); error = VOP_READ(ttyvp, uio, flag, NOCRED); VOP_UNLOCK(ttyvp, 0, p); return (error); } /*ARGSUSED*/ int cttywrite(dev, uio, flag) dev_t dev; struct uio *uio; int flag; { struct proc *p = uio->uio_procp; register struct vnode *ttyvp = cttyvp(uio->uio_procp); int error; if (ttyvp == NULL) return (EIO); vn_lock(ttyvp, LK_EXCLUSIVE | LK_RETRY, p); error = VOP_WRITE(ttyvp, uio, flag, NOCRED); VOP_UNLOCK(ttyvp, 0, p); return (error); } /*ARGSUSED*/ int cttyioctl(dev, cmd, addr, flag, p) dev_t dev; u_long cmd; caddr_t addr; int flag; struct proc *p; { struct vnode *ttyvp = cttyvp(p); if (ttyvp == NULL) return (EIO); if (cmd == TIOCSCTTY) /* XXX */ return (EINVAL); if (cmd == TIOCNOTTY) { if (!SESS_LEADER(p)) { p->p_flag &= ~P_CONTROLT; return (0); } else return (EINVAL); } return (VOP_IOCTL(ttyvp, cmd, addr, flag, NOCRED, p)); } /*ARGSUSED*/ int cttyselect(dev, flag, p) dev_t dev; int flag; struct proc *p; { struct vnode *ttyvp = cttyvp(p); if (ttyvp == NULL) return (1); /* try operation to get EOF/failure */ return (VOP_SELECT(ttyvp, flag, FREAD|FWRITE, NOCRED, p)); }