xref: /freebsd/sbin/fdisk/fdisk_mbr_enc.c (revision ac8e5d02cf9fcbe09e2077499804d791fc70122a)
1*ac8e5d02SConrad Meyer /*-
2*ac8e5d02SConrad Meyer  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3*ac8e5d02SConrad Meyer  *
4*ac8e5d02SConrad Meyer  * Copyright (c) 2003 Poul-Henning Kamp
5*ac8e5d02SConrad Meyer  * All rights reserved.
6*ac8e5d02SConrad Meyer  *
7*ac8e5d02SConrad Meyer  * Redistribution and use in source and binary forms, with or without
8*ac8e5d02SConrad Meyer  * modification, are permitted provided that the following conditions
9*ac8e5d02SConrad Meyer  * are met:
10*ac8e5d02SConrad Meyer  * 1. Redistributions of source code must retain the above copyright
11*ac8e5d02SConrad Meyer  *    notice, this list of conditions and the following disclaimer.
12*ac8e5d02SConrad Meyer  * 2. Redistributions in binary form must reproduce the above copyright
13*ac8e5d02SConrad Meyer  *    notice, this list of conditions and the following disclaimer in the
14*ac8e5d02SConrad Meyer  *    documentation and/or other materials provided with the distribution.
15*ac8e5d02SConrad Meyer  *
16*ac8e5d02SConrad Meyer  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17*ac8e5d02SConrad Meyer  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18*ac8e5d02SConrad Meyer  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19*ac8e5d02SConrad Meyer  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20*ac8e5d02SConrad Meyer  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21*ac8e5d02SConrad Meyer  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22*ac8e5d02SConrad Meyer  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23*ac8e5d02SConrad Meyer  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24*ac8e5d02SConrad Meyer  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25*ac8e5d02SConrad Meyer  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26*ac8e5d02SConrad Meyer  * SUCH DAMAGE.
27*ac8e5d02SConrad Meyer  */
28*ac8e5d02SConrad Meyer 
29*ac8e5d02SConrad Meyer /* Functions to encode or decode struct dos_partition into a bytestream
30*ac8e5d02SConrad Meyer  * of correct endianness and packing.  These functions do no validation
31*ac8e5d02SConrad Meyer  * or sanity checking, they only pack/unpack the fields correctly.
32*ac8e5d02SConrad Meyer  *
33*ac8e5d02SConrad Meyer  * NB!  This file must be usable both in kernel and userland.
34*ac8e5d02SConrad Meyer  */
35*ac8e5d02SConrad Meyer 
36*ac8e5d02SConrad Meyer #include <sys/cdefs.h>
37*ac8e5d02SConrad Meyer __FBSDID("$FreeBSD$");
38*ac8e5d02SConrad Meyer 
39*ac8e5d02SConrad Meyer #include <sys/types.h>
40*ac8e5d02SConrad Meyer #include <sys/diskmbr.h>
41*ac8e5d02SConrad Meyer #include <sys/endian.h>
42*ac8e5d02SConrad Meyer 
43*ac8e5d02SConrad Meyer #include "fdisk_mbr_enc.h"
44*ac8e5d02SConrad Meyer 
45*ac8e5d02SConrad Meyer void
46*ac8e5d02SConrad Meyer dos_partition_dec(void const *pp, struct dos_partition *d)
47*ac8e5d02SConrad Meyer {
48*ac8e5d02SConrad Meyer 	unsigned char const *p = pp;
49*ac8e5d02SConrad Meyer 
50*ac8e5d02SConrad Meyer 	d->dp_flag = p[0];
51*ac8e5d02SConrad Meyer 	d->dp_shd = p[1];
52*ac8e5d02SConrad Meyer 	d->dp_ssect = p[2];
53*ac8e5d02SConrad Meyer 	d->dp_scyl = p[3];
54*ac8e5d02SConrad Meyer 	d->dp_typ = p[4];
55*ac8e5d02SConrad Meyer 	d->dp_ehd = p[5];
56*ac8e5d02SConrad Meyer 	d->dp_esect = p[6];
57*ac8e5d02SConrad Meyer 	d->dp_ecyl = p[7];
58*ac8e5d02SConrad Meyer 	d->dp_start = le32dec(p + 8);
59*ac8e5d02SConrad Meyer 	d->dp_size = le32dec(p + 12);
60*ac8e5d02SConrad Meyer }
61*ac8e5d02SConrad Meyer 
62*ac8e5d02SConrad Meyer void
63*ac8e5d02SConrad Meyer dos_partition_enc(void *pp, struct dos_partition *d)
64*ac8e5d02SConrad Meyer {
65*ac8e5d02SConrad Meyer 	unsigned char *p = pp;
66*ac8e5d02SConrad Meyer 
67*ac8e5d02SConrad Meyer 	p[0] = d->dp_flag;
68*ac8e5d02SConrad Meyer 	p[1] = d->dp_shd;
69*ac8e5d02SConrad Meyer 	p[2] = d->dp_ssect;
70*ac8e5d02SConrad Meyer 	p[3] = d->dp_scyl;
71*ac8e5d02SConrad Meyer 	p[4] = d->dp_typ;
72*ac8e5d02SConrad Meyer 	p[5] = d->dp_ehd;
73*ac8e5d02SConrad Meyer 	p[6] = d->dp_esect;
74*ac8e5d02SConrad Meyer 	p[7] = d->dp_ecyl;
75*ac8e5d02SConrad Meyer 	le32enc(p + 8, d->dp_start);
76*ac8e5d02SConrad Meyer 	le32enc(p + 12, d->dp_size);
77*ac8e5d02SConrad Meyer }
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