xref: /minix/lib/libutil/secure_path.c (revision 0a6a1f1d)
1 /*	$NetBSD: secure_path.c,v 1.2 2003/01/06 20:30:30 wiz Exp $	*/
2 
3 /*-
4  * Copyright (c) 1995,1997 Berkeley Software Design, Inc. All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. All advertising materials mentioning features or use of this software
15  *    must display the following acknowledgement:
16  *	This product includes software developed by Berkeley Software Design,
17  *	Inc.
18  * 4. The name of Berkeley Software Design, Inc.  may not be used to endorse
19  *    or promote products derived from this software without specific prior
20  *    written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY BERKELEY SOFTWARE DESIGN, INC. ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL BERKELEY SOFTWARE DESIGN, INC. BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  *	BSDI login_cap.c,v 2.13 1998/02/07 03:17:05 prb Exp
35  */
36 
37 #include <sys/cdefs.h>
38 #if defined(LIBC_SCCS) && !defined(lint)
39 __RCSID("$NetBSD: secure_path.c,v 1.2 2003/01/06 20:30:30 wiz Exp $");
40 #endif /* LIBC_SCCS and not lint */
41 
42 #include <sys/types.h>
43 #include <sys/stat.h>
44 
45 #include <assert.h>
46 #include <syslog.h>
47 #include <util.h>
48 
49 int
50 secure_path(const char *path)
51 {
52 	struct stat sb;
53 
54 	_DIAGASSERT(path != NULL);
55 
56 	/*
57 	 * If not a regular file, or is owned/writable by someone
58 	 * other than root, quit.
59 	 */
60 	if (lstat(path, &sb) < 0)
61 		/* syslog(LOG_ERR, "cannot stat %s: %m", path) */;
62 	else if (!S_ISREG(sb.st_mode))
63 		syslog(LOG_ERR, "%s: not a regular file", path);
64 	else if (sb.st_uid != 0)
65 		syslog(LOG_ERR, "%s: not owned by root", path);
66 	else if ((sb.st_mode & (S_IWGRP | S_IWOTH)) != 0)
67 		syslog(LOG_ERR, "%s: writable by non-root", path);
68 	else
69 		return (0);
70 
71 	return (-1);
72 }
73