1/*	$NetBSD: safefile.c,v 1.4 2006/09/09 16:22:10 manu Exp $	*/
2
3/*	$KAME: safefile.c,v 1.5 2001/03/05 19:54:06 thorpej Exp $	*/
4
5/*
6 * Copyright (C) 2000 WIDE Project.
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 3. Neither the name of the project nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#include "config.h"
35
36#include <sys/types.h>
37#include <sys/stat.h>
38#include <sys/socket.h>
39#include <netinet/in.h>
40#include <unistd.h>
41
42#include "plog.h"
43#include "debug.h"
44#include "misc.h"
45#include "safefile.h"
46
47int
48safefile(path, secret)
49	const char *path;
50	int secret;
51{
52	struct stat s;
53	uid_t me;
54
55	/* no setuid */
56	if (getuid() != geteuid()) {
57		plog(LLV_ERROR, LOCATION, NULL,
58		    "setuid'ed execution not allowed\n");
59		return -1;
60	}
61
62	if (stat(path, &s) != 0)
63		return -1;
64
65	/* the file must be owned by the running uid */
66	me = getuid();
67	if (s.st_uid != me) {
68		plog(LLV_ERROR, LOCATION, NULL,
69		    "%s has invalid owner uid\n", path);
70		return -1;
71	}
72
73	switch (s.st_mode & S_IFMT) {
74	case S_IFREG:
75		break;
76	default:
77		plog(LLV_ERROR, LOCATION, NULL,
78		    "%s is an invalid file type 0x%x\n", path,
79		    (s.st_mode & S_IFMT));
80		return -1;
81	}
82
83	/* secret file should not be read by others */
84	if (secret) {
85		if ((s.st_mode & S_IRWXG) != 0 || (s.st_mode & S_IRWXO) != 0) {
86			plog(LLV_ERROR, LOCATION, NULL,
87			    "%s has weak file permission\n", path);
88			return -1;
89		}
90	}
91
92	return 0;
93}
94