1/*
2 * volume_id - reads filesystem label and uuid
3 *
4 * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
5 *
6 *	This program is free software; you can redistribute it and/or modify it
7 *	under the terms of the GNU General Public License as published by the
8 *	Free Software Foundation version 2 of the License.
9 */
10
11#ifndef _GNU_SOURCE
12#define _GNU_SOURCE 1
13#endif
14
15#ifdef HAVE_CONFIG_H
16#  include <config.h>
17#endif
18
19#include <stdio.h>
20#include <stdlib.h>
21#include <unistd.h>
22#include <string.h>
23#include <errno.h>
24#include <ctype.h>
25
26#include "libvolume_id.h"
27#include "util.h"
28
29struct lvm1_super_block {
30	uint8_t	id[2];
31} PACKED;
32
33struct lvm2_super_block {
34	uint8_t		id[8];
35	uint64_t	sector_xl;
36	uint32_t	crc_xl;
37	uint32_t	offset_xl;
38	uint8_t		type[8];
39} PACKED;
40
41#define LVM1_SB_OFF			0x400
42#define LVM1_MAGIC			"HM"
43
44int volume_id_probe_lvm1(struct volume_id *id, uint64_t off, uint64_t size)
45{
46	const uint8_t *buf;
47	struct lvm1_super_block *lvm;
48
49	info("probing at offset 0x%llx", (unsigned long long) off);
50
51	buf = volume_id_get_buffer(id, off + LVM1_SB_OFF, 0x800);
52	if (buf == NULL)
53		return -1;
54
55	lvm = (struct lvm1_super_block *) buf;
56
57	if (memcmp(lvm->id, LVM1_MAGIC, 2) != 0)
58		return -1;
59
60	volume_id_set_usage(id, VOLUME_ID_RAID);
61	id->type = "LVM1_member";
62
63	return 0;
64}
65
66#define LVM2_LABEL_ID			"LABELONE"
67#define LVM2LABEL_SCAN_SECTORS		4
68
69int volume_id_probe_lvm2(struct volume_id *id, uint64_t off, uint64_t size)
70{
71	const uint8_t *buf;
72	unsigned int soff;
73	struct lvm2_super_block *lvm;
74
75	dbg("probing at offset 0x%llx", (unsigned long long) off);
76
77	buf = volume_id_get_buffer(id, off, LVM2LABEL_SCAN_SECTORS * 0x200);
78	if (buf == NULL)
79		return -1;
80
81
82	for (soff = 0; soff < LVM2LABEL_SCAN_SECTORS * 0x200; soff += 0x200) {
83		lvm = (struct lvm2_super_block *) &buf[soff];
84
85		if (memcmp(lvm->id, LVM2_LABEL_ID, 8) == 0)
86			goto found;
87	}
88
89	return -1;
90
91found:
92	memcpy(id->type_version, lvm->type, 8);
93	volume_id_set_usage(id, VOLUME_ID_RAID);
94	id->type = "LVM2_member";
95
96	return 0;
97}
98