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Diffstat (limited to 'libparted/fs/fat/bootsector.h')
| -rw-r--r-- | libparted/fs/fat/bootsector.h | 126 |
1 files changed, 126 insertions, 0 deletions
diff --git a/libparted/fs/fat/bootsector.h b/libparted/fs/fat/bootsector.h new file mode 100644 index 0000000..328ba2f --- /dev/null +++ b/libparted/fs/fat/bootsector.h @@ -0,0 +1,126 @@ +/* + libparted + Copyright (C) 1998-2000, 2007, 2009-2014, 2019-2023 Free Software + Foundation, Inc. + + 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 3 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 PED_FAT_BOOTSECTOR_H +#define PED_FAT_BOOTSECTOR_H + +typedef struct _FatBootSector FatBootSector; +typedef struct _FatInfoSector FatInfoSector; + +#include "fat.h" + +#define FAT32_INFO_MAGIC1 0x41615252 +#define FAT32_INFO_MAGIC2 0x61417272 +#define FAT32_INFO_MAGIC3 0xaa55 + +/* stolen from mkdosfs, by Dave Hudson */ + +#define FAT_BOOT_MESSAGE \ +"This partition does not have an operating system loader installed on it.\n\r"\ +"Press a key to reboot..." + +#define FAT_BOOT_JUMP "\xeb\x58\x90" /* jmp +5a */ + +#define FAT_BOOT_CODE "\x0e" /* push cs */ \ + "\x1f" /* pop ds */ \ + "\xbe\x74\x7e" /* mov si, offset message */ \ + /* write_msg_loop: */ \ + "\xac" /* lodsb */ \ + "\x22\xc0" /* and al, al */ \ + "\x74\x06" /* jz done (+8) */ \ + "\xb4\x0e" /* mov ah, 0x0e */ \ + "\xcd\x10" /* int 0x10 */ \ + "\xeb\xf5" /* jmp write_msg_loop */ \ + /* done: */ \ + "\xb4\x00" /* mov ah, 0x00 */ \ + "\xcd\x16" /* int 0x16 */ \ + "\xb4\x00" /* mov ah, 0x00 */ \ + "\xcd\x19" /* int 0x19 */ \ + "\xeb\xfe" /* jmp +0 - in case int 0x19 */ \ + /* doesn't work */ \ + /* message: */ \ + FAT_BOOT_MESSAGE + +#define FAT_BOOT_CODE_LENGTH 128 + +struct __attribute__ ((packed)) _FatBootSector { + uint8_t boot_jump[3]; /* 00: Boot strap short or near jump */ + uint8_t system_id[8]; /* 03: system name */ + uint16_t sector_size; /* 0b: bytes per logical sector */ + uint8_t cluster_size; /* 0d: sectors/cluster */ + uint16_t reserved; /* 0e: reserved sectors */ + uint8_t fats; /* 10: number of FATs */ + uint16_t dir_entries; /* 11: number of root directory entries */ + uint16_t sectors; /* 13: if 0, total_sect supersedes */ + uint8_t media; /* 15: media code */ + uint16_t fat_length; /* 16: sectors/FAT for FAT12/16 */ + uint16_t secs_track; /* 18: sectors per track */ + uint16_t heads; /* 1a: number of heads */ + uint32_t hidden; /* 1c: hidden sectors (partition start) */ + uint32_t sector_count; /* 20: no. of sectors (if sectors == 0) */ + + union __attribute__ ((packed)) { + /* FAT16 fields */ + struct __attribute__ ((packed)) { + uint8_t drive_num; /* 24: */ + uint8_t empty_1; /* 25: */ + uint8_t ext_signature; /* 26: always 0x29 */ + uint32_t serial_number; /* 27: */ + uint8_t volume_name [11]; /* 2b: */ + uint8_t fat_name [8]; /* 36: */ + uint8_t boot_code[448]; /* 3f: Boot code (or message) */ + } fat16; + /* FAT32 fields */ + struct __attribute__ ((packed)) { + uint32_t fat_length; /* 24: size of FAT in sectors */ + uint16_t flags; /* 28: bit8: fat mirroring, low4: active fat */ + uint16_t version; /* 2a: minor * 256 + major */ + uint32_t root_dir_cluster; /* 2c: */ + uint16_t info_sector; /* 30: */ + uint16_t backup_sector; /* 32: */ + uint8_t empty_1 [12]; /* 34: */ + uint16_t drive_num; /* 40: */ + uint8_t ext_signature; /* 42: always 0x29 */ + uint32_t serial_number; /* 43: */ + uint8_t volume_name [11]; /* 47: */ + uint8_t fat_name [8]; /* 52: */ + uint8_t boot_code[420]; /* 5a: Boot code (or message) */ + } fat32; + } u; + + uint16_t boot_sign; /* 1fe: always 0xAA55 */ +}; + +struct __attribute__ ((packed)) _FatInfoSector { + uint32_t signature_1; /* should be 0x41615252 */ + uint8_t unused [480]; + uint32_t signature_2; /* should be 0x61417272 */ + uint32_t free_clusters; + uint32_t next_cluster; /* most recently allocated cluster */ + uint8_t unused2 [0xe]; + uint16_t signature_3; /* should be 0xaa55 */ +}; + +int fat_boot_sector_read (FatBootSector** bs, const PedGeometry* geom); +FatType fat_boot_sector_probe_type (const FatBootSector* bs, + const PedGeometry* geom); +int fat_boot_sector_analyse (FatBootSector* bs, PedFileSystem* fs); + + +#endif /* PED_FAT_BOOTSECTOR_H */ |