kernel/syscall/mknod.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21
  22 /*
  23  * Copyright (c) 1994, 2010, Oracle and/or its affiliates. All rights reserved.
  24  */
  25
  26 /*      Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T     */
  27 /*        All Rights Reserved   */
  28
  29 /*
  30  * Portions of this source code were derived from Berkeley 4.3 BSD
  31  * under license from the Regents of the University of California.
  32  */
  33
  34 #include <sys/param.h>
  35 #include <sys/isa_defs.h>
  36 #include <sys/types.h>
  37 #include <sys/sysmacros.h>
  38 #include <sys/user.h>
  39 #include <sys/systm.h>
  40 #include <sys/errno.h>
  41 #include <sys/stat.h>
  42 #include <sys/vnode.h>
  43 #include <sys/file.h>
  44 #include <sys/fcntl.h>
  45 #include <sys/mode.h>
  46 #include <sys/uio.h>
  47 #include <sys/mkdev.h>
  48 #include <sys/policy.h>
  49 #include <sys/debug.h>
  50 #include <c2/audit.h>
  51
  52 /*
  53  * Create a special file, a regular file, or a FIFO.
  54  * fname - pathname passed by user
  55  * fmode - mode of pathname
  56  * dev = device number - b/c specials only
  57  */
  58 int
  59 mknodat(int fd, char *fname, mode_t fmode, dev_t dev)
  60 {
  61         vnode_t *startvp;
  62         vnode_t *vp;
  63         struct vattr vattr;
  64         int error;
  65         enum create why;
  66
  67         /*
  68          * Zero type is equivalent to a regular file.
  69          */
  70         if ((fmode & S_IFMT) == 0)
  71                 fmode |= S_IFREG;
  72
  73         /*
  74          * Must be privileged unless making a FIFO node.
  75          */
  76         if (((fmode & S_IFMT) != S_IFIFO) && secpolicy_sys_devices(CRED()) != 0)
  77                 return (set_errno(EPERM));
  78         /*
  79          * Set up desired attributes and vn_create the file.
  80          */
  81         vattr.va_type = IFTOVT(fmode);
  82         vattr.va_mode = fmode & MODEMASK;
  83         vattr.va_mask = AT_TYPE|AT_MODE;
  84         if (vattr.va_type == VCHR || vattr.va_type == VBLK) {
  85                 if (get_udatamodel() != DATAMODEL_NATIVE)
  86                         dev = expldev(dev);
  87                 if (dev == NODEV || (getemajor(dev)) == (major_t)NODEV)
  88                         return (set_errno(EINVAL));
  89                 vattr.va_rdev = dev;
  90                 vattr.va_mask |= AT_RDEV;
  91         }
  92
  93         if (fname == NULL)
  94                 return (set_errno(EFAULT));
  95         if ((error = fgetstartvp(fd, fname, &startvp)) != 0)
  96                 return (set_errno(error));
  97         if (AU_AUDITING() && startvp != NULL)
  98                 audit_setfsat_path(1);
  99
 100         why = ((fmode & S_IFMT) == S_IFDIR) ? CRMKDIR : CRMKNOD;
 101         error = vn_createat(fname, UIO_USERSPACE, &vattr, EXCL, 0, &vp,
 102             why, 0,  PTOU(curproc)->u_cmask, startvp);
 103         if (startvp != NULL)
 104                 VN_RELE(startvp);
 105         if (error)
 106                 return (set_errno(error));
 107         VN_RELE(vp);
 108         return (0);
 109 }