Net2/usr/src/usr.sbin/chroot/chroot.c

/*
 * Copyright (c) 1988 The Regents of the University of California.
 * 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
 */

#ifndef lint
char copyright[] =
"@(#) Copyright (c) 1988 The Regents of the University of California.\n\
 All rights reserved.\n";
#endif /* not lint */

#ifndef lint
static char sccsid[] = "@(#)chroot.c	5.8 (Berkeley) 6/1/90";
#endif /* not lint */

#include <stdio.h>
#include <paths.h>

main(argc, argv)
	int argc;
	char **argv;
{
	extern int errno;
	char *shell, *getenv(), *strerror();

	if (argc < 2) {
		(void)fprintf(stderr, "usage: chroot newroot [command]\n");
		exit(1);
	}
	if (chdir(argv[1]) || chroot("."))
		fatal(argv[1]);
	if (argv[2]) {
		execvp(argv[2], &argv[2]);
		fatal(argv[2]);
	} else {
		if (!(shell = getenv("SHELL")))
			shell = _PATH_BSHELL;
		execlp(shell, shell, "-i", (char *)NULL);
		fatal(shell);
	}
	/* NOTREACHED */
}

fatal(msg)
	char *msg;
{
	extern int errno;

	(void)fprintf(stderr, "chroot: %s: %s\n", msg, strerror(errno));
	exit(1);
}