1 /* $NetBSD: magic.c,v 1.3 2009/03/14 15:36:03 dsl Exp $ */
2
3 /*
4 * Copyright (c) 1999 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Julian Coleman, Waldi Ravens and Leo Weppelman.
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 "privahdi.h"
33 #include <stdlib.h>
34
35 /*
36 * Check label magic numbers for AHDI partitions
37 */
38 int
check_magic(int fd,u_int offset,int flags)39 check_magic(int fd, u_int offset, int flags)
40 {
41 u_char *bblk;
42 u_int nsec;
43 int rv = 1;
44
45 nsec = (BBMINSIZE + (DEV_BSIZE - 1)) / DEV_BSIZE;
46 bblk = disk_read(fd, offset, nsec);
47 if (bblk != NULL) {
48 u_int *end, *p;
49
50 end = (u_int *)&bblk[BBMINSIZE - sizeof(struct disklabel)];
51 for (p = (u_int *)bblk; p < end; ++p) {
52 struct disklabel *dl = (struct disklabel *)&p[1];
53 if (((p[0] == NBDAMAGIC && offset == 0 &&
54 !(flags & FORCE_AHDI)) ||
55 (p[0] == AHDIMAGIC && offset != 0) ||
56 (u_char *)dl - bblk == 7168) &&
57 dl->d_npartitions <= MAXPARTITIONS &&
58 dl->d_magic2 == DISKMAGIC &&
59 dl->d_magic == DISKMAGIC &&
60 dkcksum(dl) == 0) {
61 rv = -3;
62 break;
63 }
64 }
65 free(bblk);
66 }
67 else
68 rv = -1;
69
70 return (rv);
71 }
72