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+/*
+ Legal Notice: Some portions of the source code contained in this file were
+ derived from the source code of Encryption for the Masses 2.02a, which is
+ Copyright (c) 1998-2000 Paul Le Roux and which is governed by the 'License
+ Agreement for Encryption for the Masses'. Modifications and additions to
+ the original source code (contained in this file) and all other portions
+ of this file are Copyright (c) 2003-2010 TrueCrypt Developers Association
+ and are governed by the TrueCrypt License 3.0 the full text of which is
+ contained in the file License.txt included in TrueCrypt binary and source
+ code distribution packages. */
+
+#include "Common/Tcdefs.h"
+#include "Platform/Platform.h"
+#include "Volume/VolumeHeader.h"
+#include "FatFormatter.h"
+#include "RandomNumberGenerator.h"
+
+namespace TrueCrypt
+{
+ struct fatparams
+ {
+ char volume_name[11];
+ uint32 num_sectors; /* total number of sectors */
+ uint32 cluster_count; /* number of clusters */
+ uint32 size_root_dir; /* size of the root directory in bytes */
+ uint32 size_fat; /* size of FAT */
+ uint32 fats;
+ uint32 media;
+ uint32 cluster_size;
+ uint32 fat_length;
+ uint16 dir_entries;
+ uint16 sector_size;
+ uint32 hidden;
+ uint16 reserved;
+ uint16 sectors;
+ uint32 total_sect;
+
+ uint16 heads;
+ uint16 secs_track;
+
+ };
+
+ static void GetFatParams (fatparams * ft)
+ {
+ uint64 volumeSize = (uint64) ft->num_sectors * ft->sector_size;
+ unsigned int fatsecs;
+
+ if(ft->cluster_size == 0) // 'Default' cluster size
+ {
+ uint32 clusterSize;
+
+ // Determine optimal cluster size to minimize FAT size (mounting delay), maximize number of files, keep 4 KB alignment, etc.
+ if (volumeSize >= 2 * BYTES_PER_TB)
+ clusterSize = 256 * BYTES_PER_KB;
+ else if (volumeSize >= 512 * BYTES_PER_GB)
+ clusterSize = 128 * BYTES_PER_KB;
+ else if (volumeSize >= 128 * BYTES_PER_GB)
+ clusterSize = 64 * BYTES_PER_KB;
+ else if (volumeSize >= 64 * BYTES_PER_GB)
+ clusterSize = 32 * BYTES_PER_KB;
+ else if (volumeSize >= 32 * BYTES_PER_GB)
+ clusterSize = 16 * BYTES_PER_KB;
+ else if (volumeSize >= 16 * BYTES_PER_GB)
+ clusterSize = 8 * BYTES_PER_KB;
+ else if (volumeSize >= 512 * BYTES_PER_MB)
+ clusterSize = 4 * BYTES_PER_KB;
+ else if (volumeSize >= 256 * BYTES_PER_MB)
+ clusterSize = 2 * BYTES_PER_KB;
+ else if (volumeSize >= 1 * BYTES_PER_MB)
+ clusterSize = 1 * BYTES_PER_KB;
+ else
+ clusterSize = 512;
+
+ ft->cluster_size = clusterSize / ft->sector_size;
+
+ if (ft->cluster_size == 0)
+ ft->cluster_size = 1;
+
+ if (ft->cluster_size * ft->sector_size > TC_MAX_FAT_CLUSTER_SIZE)
+ ft->cluster_size = TC_MAX_FAT_CLUSTER_SIZE / ft->sector_size;
+
+ if (ft->cluster_size > 128)
+ ft->cluster_size = 128;
+ }
+
+ if (volumeSize <= TC_MAX_FAT_CLUSTER_SIZE * 4)
+ ft->cluster_size = 1;
+
+ // Geometry always set to SECTORS/1/1
+ ft->secs_track = 1;
+ ft->heads = 1;
+
+ ft->dir_entries = 512;
+ ft->fats = 2;
+ ft->media = 0xf8;
+ ft->hidden = 0;
+
+ ft->size_root_dir = ft->dir_entries * 32;
+
+ // FAT12
+ ft->size_fat = 12;
+ ft->reserved = 2;
+ fatsecs = ft->num_sectors - (ft->size_root_dir + ft->sector_size - 1) / ft->sector_size - ft->reserved;
+ ft->cluster_count = (int) (((int64) fatsecs * ft->sector_size) / (ft->cluster_size * ft->sector_size));
+ ft->fat_length = (((ft->cluster_count * 3 + 1) >> 1) + ft->sector_size - 1) / ft->sector_size;
+
+ if (ft->cluster_count >= 4085) // FAT16
+ {
+ ft->size_fat = 16;
+ ft->reserved = 2;
+ fatsecs = ft->num_sectors - (ft->size_root_dir + ft->sector_size - 1) / ft->sector_size - ft->reserved;
+ ft->cluster_count = (int) (((int64) fatsecs * ft->sector_size) / (ft->cluster_size * ft->sector_size));
+ ft->fat_length = (ft->cluster_count * 2 + ft->sector_size - 1) / ft->sector_size;
+ }
+
+ if(ft->cluster_count >= 65525) // FAT32
+ {
+ ft->size_fat = 32;
+ ft->reserved = 32 - 1;
+
+ do
+ {
+ ft->reserved++;
+
+ fatsecs = ft->num_sectors - ft->reserved;
+ ft->size_root_dir = ft->cluster_size * ft->sector_size;
+ ft->cluster_count = (int) (((int64) fatsecs * ft->sector_size) / (ft->cluster_size * ft->sector_size));
+ ft->fat_length = (ft->cluster_count * 4 + ft->sector_size - 1) / ft->sector_size;
+
+ // Align data area on TC_MAX_VOLUME_SECTOR_SIZE
+
+ } while (ft->sector_size == TC_SECTOR_SIZE_LEGACY
+ && (ft->reserved * ft->sector_size + ft->fat_length * ft->fats * ft->sector_size) % TC_MAX_VOLUME_SECTOR_SIZE != 0);
+ }
+
+ ft->cluster_count -= ft->fat_length * ft->fats / ft->cluster_size;
+
+ if (ft->num_sectors >= 65536 || ft->size_fat == 32)
+ {
+ ft->sectors = 0;
+ ft->total_sect = ft->num_sectors;
+ }
+ else
+ {
+ ft->sectors = (uint16) ft->num_sectors;
+ ft->total_sect = 0;
+ }
+ }
+
+ static void PutBoot (fatparams * ft, byte *boot, uint32 volumeId)
+ {
+ int cnt = 0;
+
+ boot[cnt++] = 0xeb; /* boot jump */
+ boot[cnt++] = 0x3c;
+ boot[cnt++] = 0x90;
+ memcpy (boot + cnt, "MSDOS5.0", 8); /* system id */
+ cnt += 8;
+ *(int16 *)(boot + cnt) = Endian::Little (ft->sector_size); /* bytes per sector */
+ cnt += 2;
+ boot[cnt++] = (int8) ft->cluster_size; /* sectors per cluster */
+ *(int16 *)(boot + cnt) = Endian::Little (ft->reserved); /* reserved sectors */
+ cnt += 2;
+ boot[cnt++] = (int8) ft->fats; /* 2 fats */
+
+ if(ft->size_fat == 32)
+ {
+ boot[cnt++] = 0x00;
+ boot[cnt++] = 0x00;
+ }
+ else
+ {
+ *(int16 *)(boot + cnt) = Endian::Little (ft->dir_entries); /* 512 root entries */
+ cnt += 2;
+ }
+
+ *(int16 *)(boot + cnt) = Endian::Little (ft->sectors); /* # sectors */
+ cnt += 2;
+ boot[cnt++] = (int8) ft->media; /* media byte */
+
+ if(ft->size_fat == 32)
+ {
+ boot[cnt++] = 0x00;
+ boot[cnt++] = 0x00;
+ }
+ else
+ {
+ *(uint16 *)(boot + cnt) = Endian::Little ((uint16) ft->fat_length); /* fat size */
+ cnt += 2;
+ }
+
+ *(int16 *)(boot + cnt) = Endian::Little (ft->secs_track); /* # sectors per track */
+ cnt += 2;
+ *(int16 *)(boot + cnt) = Endian::Little (ft->heads); /* # heads */
+ cnt += 2;
+ *(int32 *)(boot + cnt) = Endian::Little (ft->hidden); /* # hidden sectors */
+ cnt += 4;
+ *(int32 *)(boot + cnt) = Endian::Little (ft->total_sect); /* # huge sectors */
+ cnt += 4;
+
+ if(ft->size_fat == 32)
+ {
+ *(int32 *)(boot + cnt) = Endian::Little (ft->fat_length); cnt += 4; /* fat size 32 */
+ boot[cnt++] = 0x00; /* ExtFlags */
+ boot[cnt++] = 0x00;
+ boot[cnt++] = 0x00; /* FSVer */
+ boot[cnt++] = 0x00;
+ boot[cnt++] = 0x02; /* RootClus */
+ boot[cnt++] = 0x00;
+ boot[cnt++] = 0x00;
+ boot[cnt++] = 0x00;
+ boot[cnt++] = 0x01; /* FSInfo */
+ boot[cnt++] = 0x00;
+ boot[cnt++] = 0x06; /* BkBootSec */
+ boot[cnt++] = 0x00;
+ memset(boot+cnt, 0, 12); cnt+=12; /* Reserved */
+ }
+
+ boot[cnt++] = 0x00; /* drive number */ // FIXED 80 > 00
+ boot[cnt++] = 0x00; /* reserved */
+ boot[cnt++] = 0x29; /* boot sig */
+
+ *(int32 *)(boot + cnt) = volumeId;
+ cnt += 4;
+
+ memcpy (boot + cnt, ft->volume_name, 11); /* vol title */
+ cnt += 11;
+
+ switch(ft->size_fat) /* filesystem type */
+ {
+ case 12: memcpy (boot + cnt, "FAT12 ", 8); break;
+ case 16: memcpy (boot + cnt, "FAT16 ", 8); break;
+ case 32: memcpy (boot + cnt, "FAT32 ", 8); break;
+ }
+ cnt += 8;
+
+ memset (boot + cnt, 0, ft->size_fat==32 ? 420:448); /* boot code */
+ cnt += ft->size_fat==32 ? 420:448;
+ boot[cnt++] = 0x55;
+ boot[cnt++] = 0xaa; /* boot sig */
+ }
+
+
+ /* FAT32 FSInfo */
+ static void PutFSInfo (byte *sector, fatparams *ft)
+ {
+ memset (sector, 0, ft->sector_size);
+ sector[3] = 0x41; /* LeadSig */
+ sector[2] = 0x61;
+ sector[1] = 0x52;
+ sector[0] = 0x52;
+ sector[484+3] = 0x61; /* StrucSig */
+ sector[484+2] = 0x41;
+ sector[484+1] = 0x72;
+ sector[484+0] = 0x72;
+
+ // Free cluster count
+ *(uint32 *)(sector + 488) = Endian::Little (ft->cluster_count - ft->size_root_dir / ft->sector_size / ft->cluster_size);
+
+ // Next free cluster
+ *(uint32 *)(sector + 492) = Endian::Little ((uint32) 2);
+
+ sector[508+3] = 0xaa; /* TrailSig */
+ sector[508+2] = 0x55;
+ sector[508+1] = 0x00;
+ sector[508+0] = 0x00;
+ }
+
+ void FatFormatter::Format (WriteSectorCallback &writeSector, uint64 deviceSize, uint32 clusterSize, uint32 sectorSize)
+ {
+ fatparams fatParams;
+
+#if TC_MAX_VOLUME_SECTOR_SIZE > 0xFFFF
+#error TC_MAX_VOLUME_SECTOR_SIZE > 0xFFFF
+#endif
+ fatParams.sector_size = (uint16) sectorSize;
+
+ if (deviceSize / fatParams.sector_size > 0xffffFFFF)
+ throw ParameterIncorrect (SRC_POS);
+
+ fatParams.num_sectors = (uint32) (deviceSize / fatParams.sector_size);
+ fatParams.cluster_size = clusterSize / fatParams.sector_size;
+ memcpy (fatParams.volume_name, "NO NAME ", 11);
+ GetFatParams (&fatParams);
+ fatparams *ft = &fatParams;
+
+ SecureBuffer sector (ft->sector_size);
+ uint32 sectorNumber = 0;
+
+ /* Write the data area */
+
+ sector.Zero();
+
+ uint32 volumeId;
+ RandomNumberGenerator::GetDataFast (BufferPtr ((byte *) &volumeId, sizeof (volumeId)));
+
+ PutBoot (ft, (byte *) sector, volumeId);
+ writeSector (sector); ++sectorNumber;
+
+ /* fat32 boot area */
+ if (ft->size_fat == 32)
+ {
+ /* fsinfo */
+ PutFSInfo((byte *) sector, ft);
+ writeSector (sector); ++sectorNumber;
+
+ /* reserved */
+ while (sectorNumber < 6)
+ {
+ sector.Zero();
+ sector[508+3] = 0xaa; /* TrailSig */
+ sector[508+2] = 0x55;
+ writeSector (sector); ++sectorNumber;
+ }
+
+ /* bootsector backup */
+ sector.Zero();
+ PutBoot (ft, (byte *) sector, volumeId);
+ writeSector (sector); ++sectorNumber;
+
+ PutFSInfo((byte *) sector, ft);
+ writeSector (sector); ++sectorNumber;
+ }
+
+ /* reserved */
+ while (sectorNumber < (uint32)ft->reserved)
+ {
+ sector.Zero();
+ writeSector (sector); ++sectorNumber;
+ }
+
+ /* write fat */
+ for (uint32 x = 1; x <= ft->fats; x++)
+ {
+ for (uint32 n = 0; n < ft->fat_length; n++)
+ {
+ sector.Zero();
+
+ if (n == 0)
+ {
+ byte fat_sig[12];
+ if (ft->size_fat == 32)
+ {
+ fat_sig[0] = (byte) ft->media;
+ fat_sig[1] = fat_sig[2] = 0xff;
+ fat_sig[3] = 0x0f;
+ fat_sig[4] = fat_sig[5] = fat_sig[6] = 0xff;
+ fat_sig[7] = 0x0f;
+ fat_sig[8] = fat_sig[9] = fat_sig[10] = 0xff;
+ fat_sig[11] = 0x0f;
+ memcpy (sector, fat_sig, 12);
+ }
+ else if (ft->size_fat == 16)
+ {
+ fat_sig[0] = (byte) ft->media;
+ fat_sig[1] = 0xff;
+ fat_sig[2] = 0xff;
+ fat_sig[3] = 0xff;
+ memcpy (sector, fat_sig, 4);
+ }
+ else if (ft->size_fat == 12)
+ {
+ fat_sig[0] = (byte) ft->media;
+ fat_sig[1] = 0xff;
+ fat_sig[2] = 0xff;
+ fat_sig[3] = 0x00;
+ memcpy (sector, fat_sig, 4);
+ }
+ }
+
+ if (!writeSector (sector))
+ return;
+ }
+ }
+
+ /* write rootdir */
+ for (uint32 x = 0; x < ft->size_root_dir / ft->sector_size; x++)
+ {
+ sector.Zero();
+ if (!writeSector (sector))
+ return;
+ }
+ }
+}