1 /* $NetBSD: getbootfile.c,v 1.6 2016/01/25 18:14:04 christos Exp $ */
2
3 /*-
4 * Copyright (c) 2000 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Thomas Klausner.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 #if defined(LIBC_SCCS) && !defined(lint)
34 __RCSID("$NetBSD: getbootfile.c,v 1.6 2016/01/25 18:14:04 christos Exp $");
35 #endif
36
37 #include <sys/param.h>
38 #include <sys/sysctl.h>
39 #include <sys/cpu.h>
40 #include <string.h>
41 #include <paths.h>
42 #include <util.h>
43
44 #ifdef CPU_BOOTED_KERNEL
45 static char name[MAXPATHLEN];
46 #endif
47
48 const char *
getbootfile(void)49 getbootfile(void)
50 {
51 #ifdef CPU_BOOTED_KERNEL
52 int mib[2];
53 size_t size;
54 #endif
55 const char *kernel;
56
57 kernel = _PATH_UNIX;
58 #ifdef CPU_BOOTED_KERNEL
59 /* find real boot-kernel name */
60 mib[0] = CTL_MACHDEP;
61 mib[1] = CPU_BOOTED_KERNEL;
62 size = sizeof(name) - 1;
63 if (sysctl(mib, 2, name + 1, &size, NULL, 0) == 0) {
64 /*
65 * traditionally, this sysctl returns the relative
66 * path of the kernel with the leading slash stripped
67 * -- could be empty, though (e.g. when netbooting).
68 */
69 if (name[1] != '\0') {
70 name[0] = '/';
71 kernel = name;
72 }
73
74 /* check if we got a valid and 'secure' filename */
75 if (strcmp(kernel, _PATH_UNIX) != 0 &&
76 secure_path(kernel) != 0) {
77 /* doesn't seems so, fall back to default */
78 kernel = _PATH_UNIX;
79 }
80 }
81 #endif
82
83 return (kernel);
84 }
85