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/*
* Copyright (c) 2011 , Julian Pidancet
* Copyright (c) 2011 , Nicolas François
* 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. The name of the copyright holders or contributors may not be used to
* endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT
* HOLDERS 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.
*/
#include <config.h>
#ident "$Id$"
#include <stdio.h>
#include <assert.h>
#include "defines.h"
#include "prototypes.h"
/*@-exitarg@*/
#include "exitcodes.h"
static void change_root (const char* newroot);
/*
* process_root_flag - chroot if given the --root option
*
* This shall be called before accessing the passwd, group, shadow,
* gshadow, useradd's default, login.defs files (non exhaustive list)
* or authenticating the caller.
*
* The audit, syslog, or locale files shall be open before
*/
extern void process_root_flag (const char* short_opt, int argc, char **argv)
{
/*
* Parse the command line options.
*/
int i;
const char *newroot = NULL;
for (i = 0; i < argc; i++) {
if ( (strcmp (argv[i], "--root") == 0)
|| (strcmp (argv[i], short_opt) == 0)) {
if (NULL != newroot) {
fprintf (stderr,
_("%s: multiple --root options\n"),
Prog);
exit (E_BAD_ARG);
}
if (i + 1 == argc) {
fprintf (stderr,
_("%s: option '%s' requires an argument\n"),
Prog, argv[i]);
exit (E_BAD_ARG);
}
newroot = argv[i + 1];
}
}
if (NULL != newroot) {
change_root (newroot);
}
}
static void change_root (const char* newroot)
{
/* Drop privileges */
if ( (setregid (getgid (), getgid ()) != 0)
|| (setreuid (getuid (), getuid ()) != 0)) {
fprintf (stderr, _("%s: failed to drop privileges (%s)\n"),
Prog, strerror (errno));
exit (EXIT_FAILURE);
}
if ('/' != newroot[0]) {
fprintf (stderr,
_("%s: invalid chroot path '%s'\n"),
Prog, newroot);
exit (E_BAD_ARG);
}
if (access (newroot, F_OK) != 0) {
fprintf(stderr,
_("%s: cannot access chroot directory %s: %s\n"),
Prog, newroot, strerror (errno));
exit (E_BAD_ARG);
}
if (chdir (newroot) != 0) {
fprintf(stderr,
_("%s: cannot chdir to chroot directory %s: %s\n"),
Prog, newroot, strerror (errno));
exit (E_BAD_ARG);
}
if (chroot (newroot) != 0) {
fprintf(stderr,
_("%s: unable to chroot to directory %s: %s\n"),
Prog, newroot, strerror (errno));
exit (E_BAD_ARG);
}
}
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