eudev/extras/volume_id/lib/hpfs.c
Karel Zak 43f7e87f54 volume_id: HPFS code clean up
* fix typo (hs vs. hbb)

 * set id->{version,usage,type} when all tests pass

 * be paranoid and don't use hs->version when "hs" source buffer was
   possibly modified by next volume_id_get_buffer() call.

Signed-off-by: Karel Zak <kzak@redhat.com>
2008-12-03 15:28:53 +01:00

117 lines
3.0 KiB
C

/*
* volume_id - reads filesystem label and uuid
*
* Copyright (C) 2005 Kay Sievers <kay.sievers@vrfy.org>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef _GNU_SOURCE
#define _GNU_SOURCE 1
#endif
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <ctype.h>
#include "libvolume_id.h"
#include "libvolume_id-private.h"
struct hpfs_boot_block
{
uint8_t jmp[3];
uint8_t oem_id[8];
uint8_t bytes_per_sector[2];
uint8_t sectors_per_cluster;
uint8_t n_reserved_sectors[2];
uint8_t n_fats;
uint8_t n_rootdir_entries[2];
uint8_t n_sectors_s[2];
uint8_t media_byte;
uint16_t sectors_per_fat;
uint16_t sectors_per_track;
uint16_t heads_per_cyl;
uint32_t n_hidden_sectors;
uint32_t n_sectors_l;
uint8_t drive_number;
uint8_t mbz;
uint8_t sig_28h;
uint8_t vol_serno[4];
uint8_t vol_label[11];
uint8_t sig_hpfs[8];
uint8_t pad[448];
uint8_t magic[2];
} PACKED;
struct hpfs_super
{
uint8_t magic[4];
uint8_t magic1[4];
uint8_t version;
} PACKED;
struct hpfs_spare_super
{
uint8_t magic[4];
uint8_t magic1[4];
} PACKED;
#define HPFS_SUPERBLOCK_OFFSET 0x2000
#define HPFS_SUPERBLOCK_SPARE_OFFSET 0x2200
int volume_id_probe_hpfs(struct volume_id *id, uint64_t off, uint64_t size)
{
struct hpfs_super *hs;
struct hpfs_spare_super *hss;
struct hpfs_boot_block *hbb;
uint8_t version;
info("probing at offset 0x%" PRIx64 "\n", off);
hs = (struct hpfs_super *) volume_id_get_buffer(id, off + HPFS_SUPERBLOCK_OFFSET, 0x400);
if (hs == NULL)
return -1;
if (memcmp(hs->magic, "\x49\xe8\x95\xf9", 4) != 0)
return -1;
hss = (struct hpfs_spare_super *) volume_id_get_buffer(id, off + HPFS_SUPERBLOCK_SPARE_OFFSET, 0x200);
if (hss == NULL)
return -1;
if (memcmp(hss->magic, "\x49\x18\x91\xf9", 4) != 0)
return -1;
version = hs->version;
/* if boot block looks valid, read label and uuid from there */
hbb = (struct hpfs_boot_block *) volume_id_get_buffer(id, off, 0x200);
if (hbb == NULL)
return -1;
if (memcmp(hbb->magic, "\x55\xaa", 2) == 0 &&
memcmp(hbb->sig_hpfs, "HPFS", 4) == 0 &&
hbb->sig_28h == 0x28) {
volume_id_set_label_raw(id, hbb->vol_label, 11);
volume_id_set_label_string(id, hbb->vol_label, 11);
volume_id_set_uuid(id, hbb->vol_serno, 0, UUID_DOS);
}
sprintf(id->type_version, "%u", version);
volume_id_set_usage(id, VOLUME_ID_FILESYSTEM);
id->type = "hpfs";
return 0;
}