1 /*
2 libparted
3 Copyright (C) 1998, 1999, 2000, 2007 Free Software Foundation, Inc.
4
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 3 of the License, or
8 (at your option) any later version.
9
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
14
15 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>.
17 */
18
19 #ifndef PED_FAT_BOOTSECTOR_H
20 #define PED_FAT_BOOTSECTOR_H
21
22 typedef struct _FatBootSector FatBootSector;
23 typedef struct _FatInfoSector FatInfoSector;
24
25 #include "fat.h"
26
27 #define FAT32_INFO_MAGIC1 0x41615252
28 #define FAT32_INFO_MAGIC2 0x61417272
29 #define FAT32_INFO_MAGIC3 0xaa55
30
31 /* stolen from mkdosfs, by Dave Hudson */
32
33 #define FAT_BOOT_MESSAGE \
34 "This partition does not have an operating system loader installed on it.\n\r"\
35 "Press a key to reboot..."
36
37 #define FAT_BOOT_JUMP "\xeb\x58\x90" /* jmp +5a */
38
39 #define FAT_BOOT_CODE "\x0e" /* push cs */ \
40 "\x1f" /* pop ds */ \
41 "\xbe\x74\x7e" /* mov si, offset message */ \
42 /* write_msg_loop: */ \
43 "\xac" /* lodsb */ \
44 "\x22\xc0" /* and al, al */ \
45 "\x74\x06" /* jz done (+8) */ \
46 "\xb4\x0e" /* mov ah, 0x0e */ \
47 "\xcd\x10" /* int 0x10 */ \
48 "\xeb\xf5" /* jmp write_msg_loop */ \
49 /* done: */ \
50 "\xb4\x00" /* mov ah, 0x00 */ \
51 "\xcd\x16" /* int 0x16 */ \
52 "\xb4\x00" /* mov ah, 0x00 */ \
53 "\xcd\x19" /* int 0x19 */ \
54 "\xeb\xfe" /* jmp +0 - in case int 0x19 */ \
55 /* doesn't work */ \
56 /* message: */ \
57 FAT_BOOT_MESSAGE
58
59 #define FAT_BOOT_CODE_LENGTH 128
60
61 #ifdef __sun
62 #define __attribute__(X) /*nothing*/
63 #endif /* __sun */
64
65 #ifdef __sun
66 #pragma pack(1)
67 #endif
68 struct __attribute__ ((packed)) _FatBootSector {
69 uint8_t boot_jump[3]; /* 00: Boot strap short or near jump */
70 uint8_t system_id[8]; /* 03: system name */
71 uint16_t sector_size; /* 0b: bytes per logical sector */
72 uint8_t cluster_size; /* 0d: sectors/cluster */
73 uint16_t reserved; /* 0e: reserved sectors */
74 uint8_t fats; /* 10: number of FATs */
75 uint16_t dir_entries; /* 11: number of root directory entries */
76 uint16_t sectors; /* 13: if 0, total_sect supersedes */
77 uint8_t media; /* 15: media code */
78 uint16_t fat_length; /* 16: sectors/FAT for FAT12/16 */
79 uint16_t secs_track; /* 18: sectors per track */
80 uint16_t heads; /* 1a: number of heads */
81 uint32_t hidden; /* 1c: hidden sectors (partition start) */
82 uint32_t sector_count; /* 20: no. of sectors (if sectors == 0) */
83
84 union __attribute__ ((packed)) {
85 /* FAT16 fields */
86 struct __attribute__ ((packed)) {
87 uint8_t drive_num; /* 24: */
88 uint8_t empty_1; /* 25: */
89 uint8_t ext_signature; /* 26: always 0x29 */
90 uint32_t serial_number; /* 27: */
91 uint8_t volume_name [11]; /* 2b: */
92 uint8_t fat_name [8]; /* 36: */
93 uint8_t boot_code[448]; /* 3f: Boot code (or message) */
94 } fat16;
95 /* FAT32 fields */
96 struct __attribute__ ((packed)) {
97 uint32_t fat_length; /* 24: size of FAT in sectors */
98 uint16_t flags; /* 28: bit8: fat mirroring, low4: active fat */
99 uint16_t version; /* 2a: minor * 256 + major */
100 uint32_t root_dir_cluster; /* 2c: */
101 uint16_t info_sector; /* 30: */
102 uint16_t backup_sector; /* 32: */
103 uint8_t empty_1 [12]; /* 34: */
104 uint16_t drive_num; /* 40: */
105 uint8_t ext_signature; /* 42: always 0x29 */
106 uint32_t serial_number; /* 43: */
107 uint8_t volume_name [11]; /* 47: */
108 uint8_t fat_name [8]; /* 52: */
109 uint8_t boot_code[420]; /* 5a: Boot code (or message) */
110 } fat32;
111 } u;
112
113 uint16_t boot_sign; /* 1fe: always 0xAA55 */
114 };
115
116 struct __attribute__ ((packed)) _FatInfoSector {
117 uint32_t signature_1; /* should be 0x41615252 */
118 uint8_t unused [480];
119 uint32_t signature_2; /* should be 0x61417272 */
120 uint32_t free_clusters;
121 uint32_t next_cluster; /* most recently allocated cluster */
122 uint8_t unused2 [0xe];
123 uint16_t signature_3; /* should be 0xaa55 */
124 };
125 #ifdef __sun
126 #pragma pack()
127 #endif
128
129 int fat_boot_sector_read (FatBootSector* bs, const PedGeometry* geom);
130 FatType fat_boot_sector_probe_type (const FatBootSector* bs,
131 const PedGeometry* geom);
132 int fat_boot_sector_analyse (FatBootSector* bs, PedFileSystem* fs);
133 int fat_boot_sector_set_boot_code (FatBootSector* bs);
134 int fat_boot_sector_generate (FatBootSector* bs, const PedFileSystem* fs);
135 int fat_boot_sector_write (const FatBootSector* bs, PedFileSystem* fs);
136
137 int fat_info_sector_read (FatInfoSector* is, const PedFileSystem* fs);
138 int fat_info_sector_generate (FatInfoSector* is, const PedFileSystem* fs);
139 int fat_info_sector_write (const FatInfoSector* is, PedFileSystem* fs);
140
141 #endif /* PED_FAT_BOOTSECTOR_H */
142