chroot/chroot_mkdirp.c

Go to the documentation of this file.
00001 // Copyright (C) 2006-2007 Benedikt Böhm <hollow@gentoo.org>
00002 //
00003 // This program is free software; you can redistribute it and/or
00004 // modify it under the terms of the GNU General Public License
00005 // as published by the Free Software Foundation; either version 2
00006 // of the License, or (at your option) any later version.
00007 //
00008 // This program is distributed in the hope that it will be useful,
00009 // but WITHOUT ANY WARRANTY; without even the implied warranty of
00010 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00011 // GNU General Public License for more details.
00012 //
00013 // You should have received a copy of the GNU General Public License
00014 // along with this program; if not, write to the Free Software
00015 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
00016 
00017 #include <unistd.h>
00018 #include <errno.h>
00019 
00020 #include "chroot.h"
00021 #include "misc.h"
00022 #include "open.h"
00023 
00024 /* go to <dir> in <root> as root
00025 ** going into the chroot before doing chdir(dir) prevents symlink attacks
00026 ** and hence is safer */
00027 int chroot_mkdirp(const char *root, const char *dir, mode_t mode)
00028 {
00029         int orig_root, new_root;
00030         int errno_orig;
00031 
00032         if ((orig_root = open_read("/")) == -1)
00033                 return -1;
00034 
00035         if (chdir(root) == -1)
00036                 return -1;
00037 
00038         if ((new_root = open_read(".")) == -1)
00039                 return -1;
00040 
00041         /* check cwdfd */
00042         if (chroot_fd(new_root) == -1)
00043                 return -1;
00044 
00045         /* now create the dir in the chroot */
00046         if (mkdirp(dir, mode) == -1)
00047                 goto err;
00048 
00049         /* break out of the chroot */
00050         chroot_fd(orig_root);
00051 
00052         return 0;
00053 
00054 err:
00055         errno_orig = errno;
00056         chroot_fd(orig_root);
00057         errno = errno_orig;
00058         return -1;
00059 }

Generated on Tue Jun 19 20:38:26 2007 for lucid by  doxygen 1.5.2