getbootfile.c revision 1.4 
1/*	$NetBSD: getbootfile.c,v 1.4 2003/10/21 00:47:46 fvdl 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 * 3. All advertising materials mentioning features or use of this software
19 *    must display the following acknowledgement:
20 *        This product includes software developed by the NetBSD
21 *        Foundation, Inc. and its contributors.
22 * 4. Neither the name of The NetBSD Foundation nor the names of its
23 *    contributors may be used to endorse or promote products derived
24 *    from this software without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36 * POSSIBILITY OF SUCH DAMAGE.
37 */
38
39#include <sys/cdefs.h>
40#if defined(LIBC_SCCS) && !defined(lint)
41__RCSID("$NetBSD: getbootfile.c,v 1.4 2003/10/21 00:47:46 fvdl Exp $");
42#endif
43
44#include <sys/param.h>
45#include <sys/sysctl.h>
46#include <machine/cpu.h>
47#include <string.h>
48#include <paths.h>
49#include <util.h>
50
51#ifdef CPU_BOOTED_KERNEL
52static char name[MAXPATHLEN];
53#endif
54
55const char *
56getbootfile(void)
57{
58#ifdef CPU_BOOTED_KERNEL
59	int mib[2];
60	size_t size;
61#endif
62	const char *kernel;
63
64	kernel = _PATH_UNIX;
65#ifdef CPU_BOOTED_KERNEL
66	/* find real boot-kernel name */
67	mib[0] = CTL_MACHDEP;
68	mib[1] = CPU_BOOTED_KERNEL;
69	size = sizeof(name) - 1;
70	if (sysctl(mib, 2, name + 1, &size, NULL, 0) == 0) {
71		/*
72		 * traditionally, this sysctl returns the relative
73		 * path of the kernel with the leading slash stripped
74		 * -- could be empty, though (e.g. when netbooting).
75		 */
76		if (name[1] != '\0') {
77			name[0] = '/';
78			kernel = name;
79		}
80
81		/* check if we got a valid and 'secure' filename */
82		if (strcmp(kernel, _PATH_UNIX) != 0 &&
83		    secure_path(kernel) != 0) {
84			/* doesn't seems so, fall back to default */
85			kernel = _PATH_UNIX;
86		}
87	}
88#endif
89
90	return (kernel);
91}
92