1/*-
2 * Copyright (c) 2003 Jake Burkholder
3 * Copyright (c) 2003 Poul-Henning Kamp
4 * Copyright (c) 2004,2005 Joerg Wunsch
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28/* Functions to encode or decode struct sun_disklabel into a bytestream
29 * of correct endianess and packing.
30 *
31 * NB!  This file must be usable both in kernel and userland.
32 */
33
34#include <sys/cdefs.h>
35__FBSDID("$FreeBSD: releng/10.3/sys/geom/geom_sunlabel_enc.c 144328 2005-03-30 09:33:10Z joerg $");
36
37#include <sys/types.h>
38#include <sys/endian.h>
39#include <sys/errno.h>
40#include <sys/sun_disklabel.h>
41#ifdef _KERNEL
42#include <sys/systm.h>
43#else
44#include <string.h>
45#endif
46
47#define	SL_TEXT		0x0
48#define	SL_TEXT_SIZEOF	0x80
49#define	SL_VTOC_VERS	0x80
50#define	SL_VTOC_VOLNAME	0x84
51#define	SL_VTOC_NPART	0x8c
52#define	SL_VTOC_MAP	0x8e
53#define	SL_VTOC_SANITY	0xbc
54#define	SL_RPM		0x1a4
55#define	SL_PCYLINDERS	0x1a6
56#define	SL_SPARESPERCYL	0x1a8
57#define	SL_INTERLEAVE	0x1ae
58#define	SL_NCYLINDERS	0x1b0
59#define	SL_ACYLINDERS	0x1b2
60#define	SL_NTRACKS	0x1b4
61#define	SL_NSECTORS	0x1b6
62#define	SL_PART		0x1bc
63#define	SL_MAGIC	0x1fc
64#define	SL_CKSUM	0x1fe
65
66#define	SDKP_CYLOFFSET	0
67#define	SDKP_NSECTORS	0x4
68#define	SDKP_SIZEOF	0x8	/* size of a partition entry */
69
70#define	SVTOC_TAG	0
71#define	SVTOC_FLAG	0x2
72#define	SVTOC_SIZEOF	0x4	/* size of a VTOC tag/flag entry */
73
74/*
75 * Decode the relevant fields of a sun disk label, and return zero if the
76 * magic and checksum works out OK.
77 */
78int
79sunlabel_dec(void const *pp, struct sun_disklabel *sl)
80{
81	const uint8_t *p;
82	size_t i;
83	u_int u;
84	uint32_t vtocsane;
85	uint16_t npart;
86
87	p = pp;
88	for (i = 0; i < sizeof(sl->sl_text); i++)
89		sl->sl_text[i] = p[SL_TEXT + i];
90	sl->sl_rpm = be16dec(p + SL_RPM);
91	sl->sl_pcylinders = be16dec(p + SL_PCYLINDERS);
92	sl->sl_sparespercyl = be16dec(p + SL_SPARESPERCYL);
93	sl->sl_interleave = be16dec(p + SL_INTERLEAVE);
94	sl->sl_ncylinders = be16dec(p + SL_NCYLINDERS);
95	sl->sl_acylinders = be16dec(p + SL_ACYLINDERS);
96	sl->sl_ntracks = be16dec(p + SL_NTRACKS);
97	sl->sl_nsectors = be16dec(p + SL_NSECTORS);
98	for (i = 0; i < SUN_NPART; i++) {
99		sl->sl_part[i].sdkp_cyloffset = be32dec(p + SL_PART +
100		    (i * SDKP_SIZEOF) + SDKP_CYLOFFSET);
101		sl->sl_part[i].sdkp_nsectors = be32dec(p + SL_PART +
102		    (i * SDKP_SIZEOF) + SDKP_NSECTORS);
103	}
104	sl->sl_magic = be16dec(p + SL_MAGIC);
105	vtocsane = be32dec(p + SL_VTOC_SANITY);
106	npart = be16dec(p + SL_VTOC_NPART);
107	if (vtocsane == SUN_VTOC_SANE && npart == SUN_NPART) {
108		/*
109		 * Seems we've got SVR4-compatible VTOC information
110		 * as well, decode it.
111		 */
112		sl->sl_vtoc_sane = vtocsane;
113		sl->sl_vtoc_vers = be32dec(p + SL_VTOC_VERS);
114		memcpy(sl->sl_vtoc_volname, p + SL_VTOC_VOLNAME,
115		    SUN_VOLNAME_LEN);
116		sl->sl_vtoc_nparts = SUN_NPART;
117		for (i = 0; i < SUN_NPART; i++) {
118			sl->sl_vtoc_map[i].svtoc_tag = be16dec(p +
119				SL_VTOC_MAP + (i * SVTOC_SIZEOF) + SVTOC_TAG);
120			sl->sl_vtoc_map[i].svtoc_flag = be16dec(p +
121				SL_VTOC_MAP + (i * SVTOC_SIZEOF) + SVTOC_FLAG);
122		}
123	}
124	for (i = u = 0; i < SUN_SIZE; i += 2)
125		u ^= be16dec(p + i);
126	if (u == 0 && sl->sl_magic == SUN_DKMAGIC)
127		return (0);
128	else
129		return (EINVAL);
130}
131
132/*
133 * Encode the relevant fields into a sun disklabel, compute new checksum.
134 */
135void
136sunlabel_enc(void *pp, struct sun_disklabel *sl)
137{
138	uint8_t *p;
139	size_t i;
140	u_int u;
141
142	p = pp;
143	for (i = 0; i < SL_TEXT_SIZEOF; i++)
144		p[SL_TEXT + i] = sl->sl_text[i];
145	be16enc(p + SL_RPM, sl->sl_rpm);
146	be16enc(p + SL_PCYLINDERS, sl->sl_pcylinders);
147	be16enc(p + SL_SPARESPERCYL, sl->sl_sparespercyl);
148	be16enc(p + SL_INTERLEAVE, sl->sl_interleave);
149	be16enc(p + SL_NCYLINDERS, sl->sl_ncylinders);
150	be16enc(p + SL_ACYLINDERS, sl->sl_acylinders);
151	be16enc(p + SL_NTRACKS, sl->sl_ntracks);
152	be16enc(p + SL_NSECTORS, sl->sl_nsectors);
153	for (i = 0; i < SUN_NPART; i++) {
154		be32enc(p + SL_PART + (i * SDKP_SIZEOF) + SDKP_CYLOFFSET,
155		    sl->sl_part[i].sdkp_cyloffset);
156		be32enc(p + SL_PART + (i * SDKP_SIZEOF) + SDKP_NSECTORS,
157		    sl->sl_part[i].sdkp_nsectors);
158	}
159	be16enc(p + SL_MAGIC, sl->sl_magic);
160	if (sl->sl_vtoc_sane == SUN_VTOC_SANE
161	    && sl->sl_vtoc_nparts == SUN_NPART) {
162		/*
163		 * Write SVR4-compatible VTOC elements.
164		 */
165		be32enc(p + SL_VTOC_VERS, sl->sl_vtoc_vers);
166		be32enc(p + SL_VTOC_SANITY, SUN_VTOC_SANE);
167		memcpy(p + SL_VTOC_VOLNAME, sl->sl_vtoc_volname,
168		    SUN_VOLNAME_LEN);
169		be16enc(p + SL_VTOC_NPART, SUN_NPART);
170		for (i = 0; i < SUN_NPART; i++) {
171			be16enc(p + SL_VTOC_MAP + (i * SVTOC_SIZEOF)
172				+ SVTOC_TAG,
173				sl->sl_vtoc_map[i].svtoc_tag);
174			be16enc(p + SL_VTOC_MAP + (i * SVTOC_SIZEOF)
175				+ SVTOC_FLAG,
176				sl->sl_vtoc_map[i].svtoc_flag);
177		}
178	}
179	for (i = u = 0; i < SUN_SIZE; i += 2)
180		u ^= be16dec(p + i);
181	be16enc(p + SL_CKSUM, u);
182}
183