shadow/libmisc/sub.c

/*
 * Copyright (c) 1989 - 1991, Julianne Frances Haugh
 * Copyright (c) 1996 - 1999, Marek Michałkiewicz
 * Copyright (c) 2003 - 2006, Tomasz Kłoczko
 * 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 <pwd.h>
#include <stdio.h>
#include <sys/types.h>
#include "prototypes.h"
#include "defines.h"
#define	BAD_SUBROOT2	"invalid root `%s' for user `%s'\n"
#define	NO_SUBROOT2	"no subsystem root `%s' for user `%s'\n"
/*
 * subsystem - change to subsystem root
 *
 *	A subsystem login is indicated by the presense of a "*" as
 *	the first character of the login shell.  The given home
 *	directory will be used as the root of a new filesystem which
 *	the user is actually logged into.
 */
void subsystem (const struct passwd *pw)
{
	/*
	 * The new root directory must begin with a "/" character.
	 */

	if (pw->pw_dir[0] != '/') {
		printf (_("Invalid root directory '%s'\n"), pw->pw_dir);
		SYSLOG ((LOG_WARN, BAD_SUBROOT2, pw->pw_dir, pw->pw_name));
		closelog ();
		exit (EXIT_FAILURE);
	}

	/*
	 * The directory must be accessible and the current process
	 * must be able to change into it.
	 */

	if (   (chdir (pw->pw_dir) != 0)
	    || (chroot (pw->pw_dir) != 0)) {
		(void) printf (_("Can't change root directory to '%s'\n"),
		               pw->pw_dir);
		SYSLOG ((LOG_WARN, NO_SUBROOT2, pw->pw_dir, pw->pw_name));
		closelog ();
		exit (EXIT_FAILURE);
	}
}