drivers/filesystems/fastfat_new/fat.h

   1 #pragma once
   2
   3 //
   4 //  Might be a good idea to have this as a shared
   5 //  header with FS Recognizer.
   6 //
   7 //
   8 // Conversion types and macros taken from internal ntifs headers
   9 //
  10 typedef union _UCHAR1
  11 {
  12     UCHAR Uchar[1];
  13     UCHAR ForceAlignment;
  14 } UCHAR1, *PUCHAR1;
  15
  16 typedef union _UCHAR2
  17 {
  18     UCHAR Uchar[2];
  19     USHORT ForceAlignment;
  20 } UCHAR2, *PUCHAR2;
  21
  22 typedef union _UCHAR4
  23 {
  24     UCHAR Uchar[4];
  25     ULONG ForceAlignment;
  26 } UCHAR4, *PUCHAR4;
  27
  28 #define CopyUchar1(Dst,Src) {                          \
  29     *((UCHAR1 *)(Dst)) = *((UNALIGNED UCHAR1 *)(Src)); \
  30 }
  31
  32 #define CopyUchar2(Dst,Src) {                          \
  33     *((UCHAR2 *)(Dst)) = *((UNALIGNED UCHAR2 *)(Src)); \
  34 }
  35
  36 #define CopyUchar4(Dst,Src) {                          \
  37     *((UCHAR4 *)(Dst)) = *((UNALIGNED UCHAR4 *)(Src)); \
  38 }
  39
  40 #define FatUnpackBios(Bios,Pbios) {                                         \
  41     CopyUchar2(&(Bios)->BytesPerSector,    &(Pbios)->BytesPerSector[0]   ); \
  42     CopyUchar1(&(Bios)->SectorsPerCluster, &(Pbios)->SectorsPerCluster[0]); \
  43     CopyUchar2(&(Bios)->ReservedSectors,   &(Pbios)->ReservedSectors[0]  ); \
  44     CopyUchar1(&(Bios)->Fats,              &(Pbios)->Fats[0]             ); \
  45     CopyUchar2(&(Bios)->RootEntries,       &(Pbios)->RootEntries[0]      ); \
  46     CopyUchar2(&(Bios)->Sectors,           &(Pbios)->Sectors[0]          ); \
  47     CopyUchar1(&(Bios)->Media,             &(Pbios)->Media[0]            ); \
  48     CopyUchar2(&(Bios)->SectorsPerFat,     &(Pbios)->SectorsPerFat[0]    ); \
  49     CopyUchar2(&(Bios)->SectorsPerTrack,   &(Pbios)->SectorsPerTrack[0]  ); \
  50     CopyUchar2(&(Bios)->Heads,             &(Pbios)->Heads[0]            ); \
  51     CopyUchar4(&(Bios)->HiddenSectors,     &(Pbios)->HiddenSectors[0]    ); \
  52     CopyUchar4(&(Bios)->LargeSectors,      &(Pbios)->LargeSectors[0]     ); \
  53     CopyUchar4(&(Bios)->LargeSectors,      &(Pbios)->LargeSectors[0]     ); \
  54     CopyUchar4(&(Bios)->LargeSectorsPerFat,&((PPACKED_BIOS_PARAMETER_BLOCK_EX)Pbios)->LargeSectorsPerFat[0]  ); \
  55     CopyUchar2(&(Bios)->ExtendedFlags,     &((PPACKED_BIOS_PARAMETER_BLOCK_EX)Pbios)->ExtendedFlags[0]       ); \
  56     CopyUchar2(&(Bios)->FsVersion,         &((PPACKED_BIOS_PARAMETER_BLOCK_EX)Pbios)->FsVersion[0]           ); \
  57     CopyUchar4(&(Bios)->RootDirFirstCluster,                                \
  58                                            &((PPACKED_BIOS_PARAMETER_BLOCK_EX)Pbios)->RootDirFirstCluster[0] ); \
  59     CopyUchar2(&(Bios)->FsInfoSector,      &((PPACKED_BIOS_PARAMETER_BLOCK_EX)Pbios)->FsInfoSector[0]        ); \
  60     CopyUchar2(&(Bios)->BackupBootSector,  &((PPACKED_BIOS_PARAMETER_BLOCK_EX)Pbios)->BackupBootSector[0]    ); \
  61 }
  62 //
  63 //  Packed versions of the BPB and Boot Sector
  64 //
  65 typedef struct _PACKED_BIOS_PARAMETER_BLOCK
  66 {
  67     UCHAR BytesPerSector[2];
  68     UCHAR SectorsPerCluster[1];
  69     UCHAR ReservedSectors[2];
  70     UCHAR Fats[1];
  71     UCHAR RootEntries[2];
  72     UCHAR Sectors[2];
  73     UCHAR Media[1];
  74     UCHAR SectorsPerFat[2];
  75     UCHAR SectorsPerTrack[2];
  76     UCHAR Heads[2];
  77     UCHAR HiddenSectors[4];
  78     UCHAR LargeSectors[4];
  79 } PACKED_BIOS_PARAMETER_BLOCK, *PPACKED_BIOS_PARAMETER_BLOCK;
  80 //  sizeof = 0x019
  81
  82 typedef struct _PACKED_BIOS_PARAMETER_BLOCK_EX
  83 {
  84     PACKED_BIOS_PARAMETER_BLOCK Block;
  85     UCHAR LargeSectorsPerFat[4];
  86     UCHAR ExtendedFlags[2];
  87     UCHAR FsVersion[2];
  88     UCHAR RootDirFirstCluster[4];
  89     UCHAR FsInfoSector[2];
  90     UCHAR BackupBootSector[2];
  91     UCHAR Reserved[12];
  92 } PACKED_BIOS_PARAMETER_BLOCK_EX, *PPACKED_BIOS_PARAMETER_BLOCK_EX;
  93 //  sizeof = 0x035 53
  94
  95 //
  96 //  Unpacked version of the BPB
  97 //
  98 typedef struct BIOS_PARAMETER_BLOCK
  99 {
 100     USHORT BytesPerSector;
 101     UCHAR SectorsPerCluster;
 102     USHORT ReservedSectors;
 103     UCHAR Fats;
 104     USHORT RootEntries;
 105     USHORT Sectors;
 106     UCHAR Media;
 107     USHORT SectorsPerFat;
 108     USHORT SectorsPerTrack;
 109     USHORT Heads;
 110     ULONG HiddenSectors;
 111     ULONG LargeSectors;
 112     ULONG LargeSectorsPerFat;
 113     union
 114     {
 115         USHORT ExtendedFlags;
 116         struct
 117         {
 118             ULONG ActiveFat:4;
 119             ULONG Reserved0:3;
 120             ULONG MirrorDisabled:1;
 121             ULONG Reserved1:8;
 122         };
 123     };
 124     USHORT FsVersion;
 125     ULONG RootDirFirstCluster;
 126     USHORT FsInfoSector;
 127     USHORT BackupBootSector;
 128 } BIOS_PARAMETER_BLOCK, *PBIOS_PARAMETER_BLOCK;
 129
 130 #define FatValidBytesPerSector(xBytes) \
 131     (!((xBytes) & ((xBytes)-1)) && (xBytes)>=0x80 && (xBytes)<=0x1000)
 132
 133 #define FatValidSectorsPerCluster(xSectors) \
 134     (!((xSectors) & ((xSectors)-1)) && (xSectors)>0 && (xSectors)<=0x80)
 135
 136 typedef struct _PACKED_BOOT_SECTOR
 137 {
 138     UCHAR Jump[3];
 139     UCHAR Oem[8];
 140     PACKED_BIOS_PARAMETER_BLOCK PackedBpb;
 141     UCHAR PhysicalDriveNumber;
 142     UCHAR CurrentHead;
 143     UCHAR Signature;
 144     UCHAR Id[4];
 145     UCHAR VolumeLabel[11];
 146     UCHAR SystemId[8];
 147 } PACKED_BOOT_SECTOR, *PPACKED_BOOT_SECTOR;
 148 //  sizeof = 0x03E
 149
 150 typedef struct _PACKED_BOOT_SECTOR_EX
 151 {
 152     UCHAR Jump[3];
 153     UCHAR Oem[8];
 154     PACKED_BIOS_PARAMETER_BLOCK_EX PackedBpb;
 155     UCHAR PhysicalDriveNumber;
 156     UCHAR CurrentHead;
 157     UCHAR Signature;
 158     UCHAR Id[4];
 159     UCHAR VolumeLabel[11];
 160     UCHAR SystemId[8];
 161 } PACKED_BOOT_SECTOR_EX, *PPACKED_BOOT_SECTOR_EX;
 162 //  sizeof = 0x060
 163
 164 #define FatBootSectorJumpValid(xMagic) \
 165     ((xMagic)[0] == 0xe9 || (xMagic)[0] == 0xeb || (xMagic)[0] == 0x49)
 166
 167 typedef struct _FSINFO_SECTOR
 168 {
 169     ULONG SectorBeginSignature;
 170     UCHAR Reserved[480];
 171     ULONG FsInfoSignature;
 172     ULONG FreeClusterCount;
 173     ULONG NextFreeCluster;
 174     UCHAR Reserved0[12];
 175     ULONG SectorEndSignature;
 176 } FSINFO_SECTOR, *PFSINFO_SECTOR;
 177 //  sizeof = 0x200
 178 #define FSINFO_SECTOR_BEGIN_SIGNATURE   0x41615252
 179 #define FSINFO_SECTOR_END_SIGNATURE     0xaa550000
 180 #define FSINFO_SIGNATURE                0x61417272
 181 //
 182 //  Cluster Markers:
 183 //
 184 #define FAT_CLUSTER_AVAILABLE           0x00000000
 185 #define FAT_CLUSTER_RESERVED            0x0ffffff0
 186 #define FAT_CLUSTER_BAD                 0x0ffffff7
 187 #define FAT_CLUSTER_LAST                0x0fffffff
 188 //
 189 //  Directory Structure:
 190 //
 191 typedef struct _FAT_TIME
 192 {
 193     union {
 194         struct {
 195             USHORT DoubleSeconds : 5;
 196             USHORT Minute : 6;
 197             USHORT Hour : 5;
 198         };
 199         USHORT Value;
 200     };
 201 } FAT_TIME, *PFAT_TIME;
 202 //
 203 //
 204 //
 205 typedef struct _FAT_DATE {
 206     union {
 207         struct {
 208             USHORT Day : 5;
 209             USHORT Month : 4;
 210             /* Relative to 1980 */
 211             USHORT Year : 7;
 212         };
 213         USHORT Value;
 214     };
 215 } FAT_DATE, *PFAT_DATE;
 216 //
 217 //
 218 //
 219 typedef struct _FAT_DATETIME {
 220     union {
 221         struct {
 222             FAT_TIME    Time;
 223             FAT_DATE    Date;
 224         };
 225         ULONG Value;
 226     };
 227 } FAT_DATETIME, *PFAT_DATETIME;
 228 //
 229 //
 230 //
 231 typedef struct _DIR_ENTRY
 232 {
 233     UCHAR FileName[11];
 234     UCHAR Attributes;
 235     UCHAR Case;
 236     UCHAR CreationTimeTenMs;
 237     FAT_DATETIME CreationDateTime;
 238     FAT_DATE LastAccessDate;
 239     union {
 240         USHORT ExtendedAttributes;
 241         USHORT FirstClusterOfFileHi;
 242     };
 243     FAT_DATETIME LastWriteDateTime;
 244     USHORT FirstCluster;
 245     ULONG FileSize;
 246 } DIR_ENTRY, *PDIR_ENTRY;
 247 //  sizeof = 0x020
 248
 249 typedef struct _LONG_FILE_NAME_ENTRY {
 250     UCHAR SeqNum;
 251     UCHAR NameA[10];
 252     UCHAR Attributes;
 253     UCHAR Type;
 254     UCHAR Checksum;
 255     USHORT NameB[6];
 256     USHORT Reserved;
 257     USHORT NameC[2];
 258 } LONG_FILE_NAME_ENTRY, *PLONG_FILE_NAME_ENTRY;
 259 //  sizeof = 0x020
 260
 261 #define FAT_LFN_NAME_LENGTH \
 262     (RTL_FIELD_SIZE(LONG_FILE_NAME_ENTRY, NameA) \
 263         + RTL_FIELD_SIZE(LONG_FILE_NAME_ENTRY, NameB) \
 264         + RTL_FIELD_SIZE(LONG_FILE_NAME_ENTRY, NameC))
 265
 266 #define FAT_FN_DIR_ENTRY_LAST       0x40
 267 #define FAT_FN_MAX_DIR_ENTIES       0x14
 268
 269 #define FAT_BYTES_PER_DIRENT        0x20
 270 #define FAT_BYTES_PER_DIRENT_LOG    0x05
 271 #define FAT_DIRENT_NEVER_USED       0x00
 272 #define FAT_DIRENT_REALLY_0E5       0x05
 273 #define FAT_DIRENT_DIRECTORY_ALIAS  0x2e
 274 #define FAT_DIRENT_DELETED          0xe5
 275
 276 #define FAT_CASE_LOWER_BASE             0x08
 277 #define FAT_CASE_LOWER_EXT              0x10
 278
 279 #define FAT_DIRENT_ATTR_READ_ONLY        0x01
 280 #define FAT_DIRENT_ATTR_HIDDEN           0x02
 281 #define FAT_DIRENT_ATTR_SYSTEM           0x04
 282 #define FAT_DIRENT_ATTR_VOLUME_ID        0x08
 283 #define FAT_DIRENT_ATTR_DIRECTORY        0x10
 284 #define FAT_DIRENT_ATTR_ARCHIVE          0x20
 285 #define FAT_DIRENT_ATTR_DEVICE           0x40
 286 #define FAT_DIRENT_ATTR_LFN              (FAT_DIRENT_ATTR_READ_ONLY | \
 287                                           FAT_DIRENT_ATTR_HIDDEN |    \
 288                                           FAT_DIRENT_ATTR_SYSTEM |    \
 289                                           FAT_DIRENT_ATTR_VOLUME_ID)