VeraCrypt/src/Core/CoreBase.cpp

288 lines
9.1 KiB
C++

/*
Copyright (c) 2008-2010 TrueCrypt Developers Association. All rights reserved.
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 <set>
#include "CoreBase.h"
#include "RandomNumberGenerator.h"
#include "Volume/Volume.h"
namespace VeraCrypt
{
CoreBase::CoreBase ()
: DeviceChangeInProgress (false)
{
}
CoreBase::~CoreBase ()
{
}
void CoreBase::ChangePassword (shared_ptr <Volume> openVolume, shared_ptr <VolumePassword> newPassword, shared_ptr <KeyfileList> newKeyfiles, shared_ptr <Pkcs5Kdf> newPkcs5Kdf, int wipeCount) const
{
if ((!newPassword || newPassword->Size() < 1) && (!newKeyfiles || newKeyfiles->empty()))
throw PasswordEmpty (SRC_POS);
if (!newPkcs5Kdf)
{
if (openVolume->GetPkcs5Kdf()->GetTrueCryptMode ())
{
newPkcs5Kdf.reset (openVolume->GetPkcs5Kdf()->Clone());
newPkcs5Kdf->SetTrueCryptMode (false);
}
else
newPkcs5Kdf = openVolume->GetPkcs5Kdf();
}
if ((openVolume->GetHeader()->GetFlags() & TC_HEADER_FLAG_ENCRYPTED_SYSTEM) != 0
&& openVolume->GetType() == VolumeType::Hidden
&& openVolume->GetPath().IsDevice())
{
throw EncryptedSystemRequired (SRC_POS);
}
RandomNumberGenerator::SetHash (newPkcs5Kdf->GetHash());
SecureBuffer newSalt (openVolume->GetSaltSize());
SecureBuffer newHeaderKey (VolumeHeader::GetLargestSerializedKeySize());
shared_ptr <VolumePassword> password (Keyfile::ApplyListToPassword (newKeyfiles, newPassword));
bool backupHeader = false;
while (true)
{
for (int i = 1; i <= wipeCount; i++)
{
if (i == wipeCount)
RandomNumberGenerator::GetData (newSalt);
else
RandomNumberGenerator::GetDataFast (newSalt);
newPkcs5Kdf->DeriveKey (newHeaderKey, *password, newSalt);
openVolume->ReEncryptHeader (backupHeader, newSalt, newHeaderKey, newPkcs5Kdf);
openVolume->GetFile()->Flush();
}
if (!openVolume->GetLayout()->HasBackupHeader() || backupHeader)
break;
backupHeader = true;
}
}
void CoreBase::ChangePassword (shared_ptr <VolumePath> volumePath, bool preserveTimestamps, shared_ptr <VolumePassword> password, shared_ptr <Pkcs5Kdf> kdf, bool truecryptMode, shared_ptr <KeyfileList> keyfiles, shared_ptr <VolumePassword> newPassword, shared_ptr <KeyfileList> newKeyfiles, shared_ptr <Pkcs5Kdf> newPkcs5Kdf, int wipeCount) const
{
shared_ptr <Volume> volume = OpenVolume (volumePath, preserveTimestamps, password, kdf, truecryptMode, keyfiles);
ChangePassword (volume, newPassword, newKeyfiles, newPkcs5Kdf, wipeCount);
}
void CoreBase::CoalesceSlotNumberAndMountPoint (MountOptions &options) const
{
if (options.SlotNumber < GetFirstSlotNumber())
{
if (options.MountPoint && !options.MountPoint->IsEmpty())
options.SlotNumber = MountPointToSlotNumber (*options.MountPoint);
else
options.SlotNumber = GetFirstFreeSlotNumber();
}
if (!IsSlotNumberAvailable (options.SlotNumber))
#ifdef TC_WINDOWS
throw DriveLetterUnavailable (SRC_POS);
#else
throw VolumeSlotUnavailable (SRC_POS);
#endif
if (!options.NoFilesystem && (!options.MountPoint || options.MountPoint->IsEmpty()))
options.MountPoint.reset (new DirectoryPath (SlotNumberToMountPoint (options.SlotNumber)));
}
void CoreBase::CreateKeyfile (const FilePath &keyfilePath) const
{
SecureBuffer keyfileBuffer (VolumePassword::MaxSize);
RandomNumberGenerator::GetData (keyfileBuffer);
File keyfile;
keyfile.Open (keyfilePath, File::CreateWrite);
keyfile.Write (keyfileBuffer);
}
VolumeSlotNumber CoreBase::GetFirstFreeSlotNumber (VolumeSlotNumber startFrom) const
{
if (startFrom < GetFirstSlotNumber())
startFrom = GetFirstSlotNumber();
set <VolumeSlotNumber> usedSlotNumbers;
foreach_ref (const VolumeInfo &volume, GetMountedVolumes())
usedSlotNumbers.insert (volume.SlotNumber);
for (VolumeSlotNumber slotNumber = startFrom; slotNumber <= GetLastSlotNumber(); ++slotNumber)
{
if (usedSlotNumbers.find (slotNumber) == usedSlotNumbers.end()
&& IsMountPointAvailable (SlotNumberToMountPoint (slotNumber)))
return slotNumber;
}
#ifdef TC_WINDOWS
throw DriveLetterUnavailable (SRC_POS);
#else
throw VolumeSlotUnavailable (SRC_POS);
#endif
}
uint64 CoreBase::GetMaxHiddenVolumeSize (shared_ptr <Volume> outerVolume) const
{
uint32 sectorSize = outerVolume->GetSectorSize();
SecureBuffer bootSectorBuffer (sectorSize);
outerVolume->ReadSectors (bootSectorBuffer, 0);
int fatType;
byte *bootSector = bootSectorBuffer.Ptr();
if (memcmp (bootSector + 54, "FAT12", 5) == 0)
fatType = 12;
else if (memcmp (bootSector + 54, "FAT16", 5) == 0)
fatType = 16;
else if (memcmp (bootSector + 82, "FAT32", 5) == 0)
fatType = 32;
else
throw ParameterIncorrect (SRC_POS);
uint32 clusterSize = bootSector[13] * sectorSize;
uint32 reservedSectorCount = Endian::Little (*(uint16 *) (bootSector + 14));
uint32 fatCount = bootSector[16];
uint64 fatSectorCount;
if (fatType == 32)
fatSectorCount = Endian::Little (*(uint32 *) (bootSector + 36));
else
fatSectorCount = Endian::Little (*(uint16 *) (bootSector + 22));
uint64 fatSize = fatSectorCount * sectorSize;
uint64 fatStartOffset = reservedSectorCount * sectorSize;
uint64 dataAreaOffset = reservedSectorCount * sectorSize + fatSize * fatCount;
if (fatType < 32)
dataAreaOffset += Endian::Little (*(uint16 *) (bootSector + 17)) * 32;
SecureBuffer sector (sectorSize);
// Find last used cluster
for (uint64 readOffset = fatStartOffset + fatSize - sectorSize;
readOffset >= fatStartOffset;
readOffset -= sectorSize)
{
outerVolume->ReadSectors (sector, readOffset);
for (int offset = sectorSize - 4; offset >= 0; offset -= 4)
{
if (*(uint32 *) (sector.Ptr() + offset))
{
uint64 clusterNumber = readOffset - fatStartOffset + offset;
if (fatType == 12)
clusterNumber = (clusterNumber * 8) / 12;
else if (fatType == 16)
clusterNumber /= 2;
else if (fatType == 32)
clusterNumber /= 4;
uint64 maxSize = outerVolume->GetSize() - dataAreaOffset;
// Some FAT entries may span over sector boundaries
if (maxSize >= clusterSize)
maxSize -= clusterSize;
uint64 clusterOffset = clusterNumber * clusterSize;
if (maxSize < clusterOffset)
return 0;
return maxSize - clusterOffset;
}
}
}
return 0;
}
shared_ptr <VolumeInfo> CoreBase::GetMountedVolume (const VolumePath &volumePath) const
{
VolumeInfoList volumes = GetMountedVolumes (volumePath);
if (volumes.empty())
return shared_ptr <VolumeInfo> ();
else
return volumes.front();
}
shared_ptr <VolumeInfo> CoreBase::GetMountedVolume (VolumeSlotNumber slot) const
{
foreach (shared_ptr <VolumeInfo> volume, GetMountedVolumes())
{
if (volume->SlotNumber == slot)
return volume;
}
return shared_ptr <VolumeInfo> ();
}
bool CoreBase::IsSlotNumberAvailable (VolumeSlotNumber slotNumber) const
{
if (!IsMountPointAvailable (SlotNumberToMountPoint (slotNumber)))
return false;
foreach_ref (const VolumeInfo &volume, GetMountedVolumes())
{
if (volume.SlotNumber == slotNumber)
return false;
}
return true;
}
bool CoreBase::IsVolumeMounted (const VolumePath &volumePath) const
{
return GetMountedVolume (volumePath);
}
shared_ptr <Volume> CoreBase::OpenVolume (shared_ptr <VolumePath> volumePath, bool preserveTimestamps, shared_ptr <VolumePassword> password, shared_ptr<Pkcs5Kdf> kdf, bool truecryptMode, shared_ptr <KeyfileList> keyfiles, VolumeProtection::Enum protection, shared_ptr <VolumePassword> protectionPassword, shared_ptr<Pkcs5Kdf> protectionKdf, shared_ptr <KeyfileList> protectionKeyfiles, bool sharedAccessAllowed, VolumeType::Enum volumeType, bool useBackupHeaders, bool partitionInSystemEncryptionScope) const
{
make_shared_auto (Volume, volume);
volume->Open (*volumePath, preserveTimestamps, password, kdf, truecryptMode, keyfiles, protection, protectionPassword, protectionKdf, protectionKeyfiles, sharedAccessAllowed, volumeType, useBackupHeaders, partitionInSystemEncryptionScope);
return volume;
}
void CoreBase::RandomizeEncryptionAlgorithmKey (shared_ptr <EncryptionAlgorithm> encryptionAlgorithm) const
{
SecureBuffer eaKey (encryptionAlgorithm->GetKeySize());
RandomNumberGenerator::GetData (eaKey);
encryptionAlgorithm->SetKey (eaKey);
SecureBuffer modeKey (encryptionAlgorithm->GetMode()->GetKeySize());
RandomNumberGenerator::GetData (modeKey);
encryptionAlgorithm->GetMode()->SetKey (modeKey);
}
void CoreBase::ReEncryptVolumeHeaderWithNewSalt (const BufferPtr &newHeaderBuffer, shared_ptr <VolumeHeader> header, shared_ptr <VolumePassword> password, shared_ptr <KeyfileList> keyfiles) const
{
shared_ptr <Pkcs5Kdf> pkcs5Kdf = header->GetPkcs5Kdf();
RandomNumberGenerator::SetHash (pkcs5Kdf->GetHash());
SecureBuffer newSalt (header->GetSaltSize());
SecureBuffer newHeaderKey (VolumeHeader::GetLargestSerializedKeySize());
shared_ptr <VolumePassword> passwordKey (Keyfile::ApplyListToPassword (keyfiles, password));
RandomNumberGenerator::GetData (newSalt);
pkcs5Kdf->DeriveKey (newHeaderKey, *passwordKey, newSalt);
header->EncryptNew (newHeaderBuffer, newSalt, newHeaderKey, pkcs5Kdf);
}
}