1/* 2 * Copyright (c) 1997-2006 Apple Computer, Inc. All rights reserved. 3 * 4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ 5 * 6 * This file contains Original Code and/or Modifications of Original Code 7 * as defined in and that are subject to the Apple Public Source License 8 * Version 2.0 (the 'License'). You may not use this file except in 9 * compliance with the License. The rights granted to you under the License 10 * may not be used to create, or enable the creation or redistribution of, 11 * unlawful or unlicensed copies of an Apple operating system, or to 12 * circumvent, violate, or enable the circumvention or violation of, any 13 * terms of an Apple operating system software license agreement. 14 * 15 * Please obtain a copy of the License at 16 * http://www.opensource.apple.com/apsl/ and read it before using this file. 17 * 18 * The Original Code and all software distributed under the License are 19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 23 * Please see the License for the specific language governing rights and 24 * limitations under the License. 25 * 26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ 27 */ 28/*- 29 * Copyright (c) 1982, 1986, 1991, 1993 30 * The Regents of the University of California. All rights reserved. 31 * 32 * Redistribution and use in source and binary forms, with or without 33 * modification, are permitted provided that the following conditions 34 * are met: 35 * 1. Redistributions of source code must retain the above copyright 36 * notice, this list of conditions and the following disclaimer. 37 * 2. Redistributions in binary form must reproduce the above copyright 38 * notice, this list of conditions and the following disclaimer in the 39 * documentation and/or other materials provided with the distribution. 40 * 3. All advertising materials mentioning features or use of this software 41 * must display the following acknowledgement: 42 * This product includes software developed by the University of 43 * California, Berkeley and its contributors. 44 * 4. Neither the name of the University nor the names of its contributors 45 * may be used to endorse or promote products derived from this software 46 * without specific prior written permission. 47 * 48 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 49 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 50 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 51 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 52 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 53 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 54 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 55 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 56 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 57 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 58 * SUCH DAMAGE. 59 * 60 * @(#)tty_tty.c 8.2 (Berkeley) 9/23/93 61 */ 62 63/* 64 * Indirect driver for controlling tty. 65 */ 66#include <sys/param.h> 67#include <sys/systm.h> 68#include <sys/conf.h> 69#include <sys/ioctl.h> 70#include <sys/proc_internal.h> 71#include <sys/tty.h> 72#include <sys/vnode_internal.h> 73#include <sys/file_internal.h> 74#include <sys/kauth.h> 75 76/* Forward declarations for cdevsw[] entry */ 77/* XXX we should consider making these static */ 78int cttyopen(dev_t dev, int flag, int mode, proc_t p); 79int cttyread(dev_t dev, struct uio *uio, int flag); 80int cttywrite(dev_t dev, struct uio *uio, int flag); 81int cttyioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, proc_t p); 82int cttyselect(dev_t dev, int flag, void* wql, proc_t p); 83static vnode_t cttyvp(proc_t p); 84 85 86int 87cttyopen(__unused dev_t dev, int flag, __unused int mode, proc_t p) 88{ 89 vnode_t ttyvp = cttyvp(p); 90 struct vfs_context context; 91 int error; 92 93 if (ttyvp == NULL) 94 return (ENXIO); 95 96 context.vc_thread = current_thread(); 97 context.vc_ucred = kauth_cred_proc_ref(p); 98 99 error = VNOP_OPEN(ttyvp, flag, &context); 100 vnode_put(ttyvp); 101 kauth_cred_unref(&context.vc_ucred); 102 103 return (error); 104} 105 106int 107cttyread(__unused dev_t dev, struct uio *uio, int flag) 108{ 109 vnode_t ttyvp = cttyvp(current_proc()); 110 struct vfs_context context; 111 int error; 112 113 if (ttyvp == NULL) 114 return (EIO); 115 116 context.vc_thread = current_thread(); 117 context.vc_ucred = NOCRED; 118 119 error = VNOP_READ(ttyvp, uio, flag, &context); 120 vnode_put(ttyvp); 121 122 return (error); 123} 124 125int 126cttywrite(__unused dev_t dev, struct uio *uio, int flag) 127{ 128 vnode_t ttyvp = cttyvp(current_proc()); 129 struct vfs_context context; 130 int error; 131 132 if (ttyvp == NULL) 133 return (EIO); 134 135 context.vc_thread = current_thread(); 136 context.vc_ucred = NOCRED; 137 138 error = VNOP_WRITE(ttyvp, uio, flag, &context); 139 vnode_put(ttyvp); 140 141 return (error); 142} 143 144int 145cttyioctl(__unused dev_t dev, u_long cmd, caddr_t addr, int flag, proc_t p) 146{ 147 vnode_t ttyvp = cttyvp(current_proc()); 148 struct vfs_context context; 149 struct session *sessp; 150 int error = 0; 151 152 if (ttyvp == NULL) 153 return (EIO); 154 if (cmd == TIOCSCTTY) { /* don't allow controlling tty to be set */ 155 error = EINVAL; /* to controlling tty -- infinite recursion */ 156 goto out; 157 } 158 if (cmd == TIOCNOTTY) { 159 sessp = proc_session(p); 160 if (!SESS_LEADER(p, sessp)) { 161 OSBitAndAtomic(~((uint32_t)P_CONTROLT), (UInt32 *)&p->p_flag); 162 if (sessp != SESSION_NULL) 163 session_rele(sessp); 164 error = 0; 165 goto out; 166 } else { 167 if (sessp != SESSION_NULL) 168 session_rele(sessp); 169 error = EINVAL; 170 goto out; 171 } 172 } 173 context.vc_thread = current_thread(); 174 context.vc_ucred = NOCRED; 175 176 error = VNOP_IOCTL(ttyvp, cmd, addr, flag, &context); 177out: 178 vnode_put(ttyvp); 179 return (error); 180} 181 182int 183cttyselect(__unused dev_t dev, int flag, void* wql, __unused proc_t p) 184{ 185 vnode_t ttyvp = cttyvp(current_proc()); 186 struct vfs_context context; 187 int error; 188 189 context.vc_thread = current_thread(); 190 context.vc_ucred = NOCRED; 191 192 if (ttyvp == NULL) 193 return (1); /* try operation to get EOF/failure */ 194 error = VNOP_SELECT(ttyvp, flag, FREAD|FWRITE, wql, &context); 195 vnode_put(ttyvp); 196 return (error); 197} 198 199/* This returns vnode with ioref */ 200static vnode_t 201cttyvp(proc_t p) 202{ 203 vnode_t vp; 204 int vid; 205 struct session *sessp; 206 207 sessp = proc_session(p); 208 209 session_lock(sessp); 210 vp = (p->p_flag & P_CONTROLT ? sessp->s_ttyvp : NULLVP); 211 vid = sessp->s_ttyvid; 212 session_unlock(sessp); 213 214 session_rele(sessp); 215 216 if (vp != NULLVP) { 217 /* cannot get an IO reference, return NULLVP */ 218 if (vnode_getwithvid(vp, vid) != 0) 219 vp = NULLVP; 220 } 221 return(vp); 222} 223 224