private void ReadHeaders()
{
long pos = _footer.DataOffset;
long maxpos = _fileStream.Length;
while (pos != -1)
{
if (pos < maxpos && pos > -1)
{
_fileStream.Position = pos;
Header hdr = Header.FromStream(_fileStream);
if (hdr.Cookie == DynamicHeader.HeaderCookie)
{
_fileStream.Position = pos;
_dynamicHeader = DynamicHeader.FromStream(_fileStream);
if (!_dynamicHeader.IsValid())
{
throw new IOException("Invalid Dynamic Disc Header");
}
}
pos = hdr.DataOffset;
}
else
{
throw new IOException("Invalid DataOffset in Disk Header");
}
}
}
private static void InitializeDifferencingInternal(Stream stream, DiskImageFile parent,
string parentAbsolutePath, string parentRelativePath, DateTime parentModificationTimeUtc)
{
Footer footer = new Footer(parent.Geometry, parent._footer.CurrentSize, FileType.Differencing);
footer.DataOffset = 512; // Offset of Dynamic Header
footer.OriginalSize = parent._footer.OriginalSize;
footer.UpdateChecksum();
byte[] footerBlock = new byte[512];
footer.ToBytes(footerBlock, 0);
long tableOffset = 512 + 1024; // Footer + Header
uint blockSize = parent._dynamicHeader == null
? DynamicHeader.DefaultBlockSize
: parent._dynamicHeader.BlockSize;
DynamicHeader dynamicHeader = new DynamicHeader(-1, tableOffset, blockSize, footer.CurrentSize);
int batSize = (dynamicHeader.MaxTableEntries * 4 + Sizes.Sector - 1) / Sizes.Sector *
Sizes.Sector;
dynamicHeader.ParentUniqueId = parent.UniqueId;
dynamicHeader.ParentTimestamp = parentModificationTimeUtc;
dynamicHeader.ParentUnicodeName = Utilities.GetFileFromPath(parentAbsolutePath);
dynamicHeader.ParentLocators[7].PlatformCode = ParentLocator.PlatformCodeWindowsAbsoluteUnicode;
dynamicHeader.ParentLocators[7].PlatformDataSpace = 512;
dynamicHeader.ParentLocators[7].PlatformDataLength = parentAbsolutePath.Length * 2;
dynamicHeader.ParentLocators[7].PlatformDataOffset = tableOffset + batSize;
dynamicHeader.ParentLocators[6].PlatformCode = ParentLocator.PlatformCodeWindowsRelativeUnicode;
dynamicHeader.ParentLocators[6].PlatformDataSpace = 512;
dynamicHeader.ParentLocators[6].PlatformDataLength = parentRelativePath.Length * 2;
dynamicHeader.ParentLocators[6].PlatformDataOffset = tableOffset + batSize + 512;
dynamicHeader.UpdateChecksum();
byte[] dynamicHeaderBlock = new byte[1024];
dynamicHeader.ToBytes(dynamicHeaderBlock, 0);
byte[] platformLocator1 = new byte[512];
Encoding.Unicode.GetBytes(parentAbsolutePath, 0, parentAbsolutePath.Length, platformLocator1, 0);
byte[] platformLocator2 = new byte[512];
Encoding.Unicode.GetBytes(parentRelativePath, 0, parentRelativePath.Length, platformLocator2, 0);
byte[] bat = new byte[batSize];
for (int i = 0; i < bat.Length; ++i)
{
bat[i] = 0xFF;
}
stream.Position = 0;
stream.Write(footerBlock, 0, 512);
stream.Write(dynamicHeaderBlock, 0, 1024);
stream.Write(bat, 0, batSize);
stream.Write(platformLocator1, 0, 512);
stream.Write(platformLocator2, 0, 512);
stream.Write(footerBlock, 0, 512);
}
protected override List <BuilderExtent> FixExtents(out long totalLength)
{
const int FooterSize = 512;
const int DynHeaderSize = 1024;
List <BuilderExtent> extents = new List <BuilderExtent>();
_footer.DataOffset = FooterSize;
DynamicHeader dynHeader = new DynamicHeader(-1, FooterSize + DynHeaderSize, _blockSize, _footer.CurrentSize);
BlockAllocationTableExtent batExtent = new BlockAllocationTableExtent(FooterSize + DynHeaderSize,
dynHeader.MaxTableEntries);
long streamPos = batExtent.Start + batExtent.Length;
foreach (Range <long, long> blockRange in StreamExtent.Blocks(_content.Extents, _blockSize))
{
for (int i = 0; i < blockRange.Count; ++i)
{
long block = blockRange.Offset + i;
long blockStart = block * _blockSize;
DataBlockExtent dataExtent = new DataBlockExtent(streamPos,
new SubStream(_content, blockStart, Math.Min(_blockSize, _content.Length - blockStart)));
extents.Add(dataExtent);
batExtent.SetEntry((int)block, (uint)(streamPos / Sizes.Sector));
streamPos += dataExtent.Length;
}
}
_footer.UpdateChecksum();
dynHeader.UpdateChecksum();
byte[] footerBuffer = new byte[FooterSize];
_footer.ToBytes(footerBuffer, 0);
byte[] dynHeaderBuffer = new byte[DynHeaderSize];
dynHeader.ToBytes(dynHeaderBuffer, 0);
// Add footer (to end)
extents.Add(new BuilderBufferExtent(streamPos, footerBuffer));
totalLength = streamPos + FooterSize;
extents.Insert(0, batExtent);
extents.Insert(0, new BuilderBufferExtent(FooterSize, dynHeaderBuffer));
extents.Insert(0, new BuilderBufferExtent(0, footerBuffer));
return(extents);
}
internal override List<BuilderExtent> FixExtents(out long totalLength)
{
const int FooterSize = 512;
const int DynHeaderSize = 1024;
List<BuilderExtent> extents = new List<BuilderExtent>();
_footer.DataOffset = FooterSize;
DynamicHeader dynHeader = new DynamicHeader(-1, FooterSize + DynHeaderSize, _blockSize, _footer.CurrentSize);
BlockAllocationTableExtent batExtent = new BlockAllocationTableExtent(FooterSize + DynHeaderSize, dynHeader.MaxTableEntries);
long streamPos = batExtent.Start + batExtent.Length;
foreach (var blockRange in StreamExtent.Blocks(_content.Extents, _blockSize))
{
for (int i = 0; i < blockRange.Count; ++i)
{
long block = blockRange.Offset + i;
long blockStart = block * _blockSize;
DataBlockExtent dataExtent = new DataBlockExtent(streamPos, new SubStream(_content, blockStart, Math.Min(_blockSize, _content.Length - blockStart)));
extents.Add(dataExtent);
batExtent.SetEntry((int)block, (uint)(streamPos / Sizes.Sector));
streamPos += dataExtent.Length;
}
}
_footer.UpdateChecksum();
dynHeader.UpdateChecksum();
byte[] footerBuffer = new byte[FooterSize];
_footer.ToBytes(footerBuffer, 0);
byte[] dynHeaderBuffer = new byte[DynHeaderSize];
dynHeader.ToBytes(dynHeaderBuffer, 0);
// Add footer (to end)
extents.Add(new BuilderBufferExtent(streamPos, footerBuffer));
totalLength = streamPos + FooterSize;
extents.Insert(0, batExtent);
extents.Insert(0, new BuilderBufferExtent(FooterSize, dynHeaderBuffer));
extents.Insert(0, new BuilderBufferExtent(0, footerBuffer));
return extents;
}
public DynamicHeader(DynamicHeader toCopy)
{
Cookie = toCopy.Cookie;
DataOffset = toCopy.DataOffset;
TableOffset = toCopy.TableOffset;
HeaderVersion = toCopy.HeaderVersion;
MaxTableEntries = toCopy.MaxTableEntries;
BlockSize = toCopy.BlockSize;
Checksum = toCopy.Checksum;
ParentUniqueId = toCopy.ParentUniqueId;
ParentTimestamp = toCopy.ParentTimestamp;
ParentUnicodeName = toCopy.ParentUnicodeName;
ParentLocators = new ParentLocator[toCopy.ParentLocators.Length];
for (int i = 0; i < ParentLocators.Length; ++i)
{
ParentLocators[i] = new ParentLocator(toCopy.ParentLocators[i]);
}
}
public DynamicHeader(DynamicHeader toCopy)
{
Cookie = toCopy.Cookie;
DataOffset = toCopy.DataOffset;
TableOffset = toCopy.TableOffset;
HeaderVersion = toCopy.HeaderVersion;
MaxTableEntries = toCopy.MaxTableEntries;
BlockSize = toCopy.BlockSize;
Checksum = toCopy.Checksum;
ParentUniqueId = toCopy.ParentUniqueId;
ParentTimestamp = toCopy.ParentTimestamp;
ParentUnicodeName = toCopy.ParentUnicodeName;
ParentLocators = new ParentLocator[toCopy.ParentLocators.Length];
for (int i = 0; i < ParentLocators.Length; ++i)
{
ParentLocators[i] = new ParentLocator(toCopy.ParentLocators[i]);
}
}
private uint CalculateChecksum()
{
DynamicHeader copy = new DynamicHeader(this);
copy.Checksum = 0;
byte[] asBytes = new byte[1024];
copy.ToBytes(asBytes, 0);
uint Checksum = 0;
foreach (uint value in asBytes)
{
Checksum += value;
}
Checksum = ~Checksum;
return(Checksum);
}
private static void InitializeDynamicInternal(Stream stream, long capacity, Geometry geometry, long blockSize)
{
if (blockSize > uint.MaxValue || blockSize < 0)
{
throw new ArgumentOutOfRangeException("blockSize", "Must be in the range 0 to uint.MaxValue");
}
if (geometry == null)
{
geometry = Geometry.FromCapacity(capacity);
// Backwards compatibility - if the geometry isn't specified, make the actual capacity a
// multiple of the disk geometry's cylinder capacity.
long cylinderSize = geometry.BytesPerSector * (long)geometry.SectorsPerTrack * geometry.HeadsPerCylinder;
capacity = (capacity / cylinderSize) * cylinderSize;
}
Footer footer = new Footer(geometry, capacity, FileType.Dynamic);
footer.DataOffset = 512; // Offset of Dynamic Header
footer.UpdateChecksum();
byte[] footerBlock = new byte[512];
footer.ToBytes(footerBlock, 0);
DynamicHeader dynamicHeader = new DynamicHeader(-1, 1024 + 512, (uint)blockSize, capacity);
dynamicHeader.UpdateChecksum();
byte[] dynamicHeaderBlock = new byte[1024];
dynamicHeader.ToBytes(dynamicHeaderBlock, 0);
int batSize = (((dynamicHeader.MaxTableEntries * 4) + Utilities.SectorSize - 1) / Utilities.SectorSize) * Utilities.SectorSize;
byte[] bat = new byte[batSize];
for (int i = 0; i < bat.Length; ++i)
{
bat[i] = 0xFF;
}
stream.Position = 0;
stream.Write(footerBlock, 0, 512);
stream.Write(dynamicHeaderBlock, 0, 1024);
stream.Write(bat, 0, batSize);
stream.Write(footerBlock, 0, 512);
}
public DynamicStream(Stream fileStream, DynamicHeader dynamicHeader, long length, SparseStream parentStream,
Ownership ownsParentStream)
{
if (fileStream == null)
{
throw new ArgumentNullException(nameof(fileStream));
}
if (dynamicHeader == null)
{
throw new ArgumentNullException(nameof(dynamicHeader));
}
if (parentStream == null)
{
throw new ArgumentNullException(nameof(parentStream));
}
if (length < 0)
{
throw new ArgumentOutOfRangeException(nameof(length), length, "Negative lengths not allowed");
}
_fileStream = fileStream;
_dynamicHeader = dynamicHeader;
_length = length;
_parentStream = parentStream;
_ownsParentStream = ownsParentStream;
_blockBitmaps = new byte[_dynamicHeader.MaxTableEntries][];
_blockBitmapSize =
(int)
MathUtilities.RoundUp(MathUtilities.Ceil(_dynamicHeader.BlockSize, Sizes.Sector * 8), Sizes.Sector);
ReadBlockAllocationTable();
// Detect where next block should go (cope if the footer is missing)
_fileStream.Position = MathUtilities.RoundDown(_fileStream.Length, Sizes.Sector) - Sizes.Sector;
byte[] footerBytes = StreamUtilities.ReadExact(_fileStream, Sizes.Sector);
Footer footer = Footer.FromBytes(footerBytes, 0);
_nextBlockStart = _fileStream.Position - (footer.IsValid() ? Sizes.Sector : 0);
}
private static void InitializeDynamicInternal(Stream stream, long capacity, Geometry geometry, long blockSize)
{
if (blockSize > uint.MaxValue || blockSize < 0)
{
throw new ArgumentOutOfRangeException(nameof(blockSize), "Must be in the range 0 to uint.MaxValue");
}
if (geometry == null)
{
geometry = Geometry.FromCapacity(capacity);
}
Footer footer = new Footer(geometry, capacity, FileType.Dynamic);
footer.DataOffset = 512; // Offset of Dynamic Header
footer.UpdateChecksum();
byte[] footerBlock = new byte[512];
footer.ToBytes(footerBlock, 0);
DynamicHeader dynamicHeader = new DynamicHeader(-1, 1024 + 512, (uint)blockSize, capacity);
dynamicHeader.UpdateChecksum();
byte[] dynamicHeaderBlock = new byte[1024];
dynamicHeader.ToBytes(dynamicHeaderBlock, 0);
int batSize = (dynamicHeader.MaxTableEntries * 4 + Sizes.Sector - 1) / Sizes.Sector *
Sizes.Sector;
byte[] bat = new byte[batSize];
for (int i = 0; i < bat.Length; ++i)
{
bat[i] = 0xFF;
}
stream.Position = 0;
stream.Write(footerBlock, 0, 512);
stream.Write(dynamicHeaderBlock, 0, 1024);
stream.Write(bat, 0, batSize);
stream.Write(footerBlock, 0, 512);
}
public DynamicStream(Stream fileStream, DynamicHeader dynamicHeader, long length, SparseStream parentStream, Ownership ownsParentStream)
{
if (fileStream == null)
{
throw new ArgumentNullException("fileStream");
}
if (dynamicHeader == null)
{
throw new ArgumentNullException("dynamicHeader");
}
if (parentStream == null)
{
throw new ArgumentNullException("parentStream");
}
if (length < 0)
{
throw new ArgumentOutOfRangeException("length", length, "Negative lengths not allowed");
}
_fileStream = fileStream;
_dynamicHeader = dynamicHeader;
_length = length;
_parentStream = parentStream;
_ownsParentStream = ownsParentStream;
_blockBitmaps = new byte[_dynamicHeader.MaxTableEntries][];
_blockBitmapSize = (int)Utilities.RoundUp((_dynamicHeader.BlockSize / Utilities.SectorSize) / 8, Utilities.SectorSize);
ReadBlockAllocationTable();
// Detect where next block should go (cope if the footer is missing)
_fileStream.Position = Utilities.RoundDown(_fileStream.Length, Utilities.SectorSize) - Utilities.SectorSize;
byte[] footerBytes = Utilities.ReadFully(_fileStream, Utilities.SectorSize);
Footer footer = Footer.FromBytes(footerBytes, 0);
_nextBlockStart = _fileStream.Position - (footer.IsValid() ? Utilities.SectorSize : 0);
}
public DynamicStream(Stream fileStream, DynamicHeader dynamicHeader, long length, SparseStream parentStream, Ownership ownsParentStream)
{
if (fileStream == null)
{
throw new ArgumentNullException("fileStream");
}
if (dynamicHeader == null)
{
throw new ArgumentNullException("dynamicHeader");
}
if (parentStream == null)
{
throw new ArgumentNullException("parentStream");
}
if (length < 0)
{
throw new ArgumentOutOfRangeException("length", length, "Negative lengths not allowed");
}
_fileStream = fileStream;
_dynamicHeader = dynamicHeader;
_length = length;
_parentStream = parentStream;
_ownsParentStream = ownsParentStream;
_blockBitmaps = new byte[_dynamicHeader.MaxTableEntries][];
_blockBitmapSize = (int)Utilities.RoundUp(Utilities.Ceil(_dynamicHeader.BlockSize, Utilities.SectorSize * 8), Utilities.SectorSize);
ReadBlockAllocationTable();
// Detect where next block should go (cope if the footer is missing)
_fileStream.Position = Utilities.RoundDown(_fileStream.Length, Utilities.SectorSize) - Utilities.SectorSize;
byte[] footerBytes = Utilities.ReadFully(_fileStream, Utilities.SectorSize);
Footer footer = Footer.FromBytes(footerBytes, 0);
_nextBlockStart = _fileStream.Position - (footer.IsValid() ? Utilities.SectorSize : 0);
}
public static DynamicHeader FromBytes(byte[] data, int offset)
{
DynamicHeader result = new DynamicHeader();
result.Cookie = Utilities.BytesToString(data, offset, 8);
result.DataOffset = Utilities.ToInt64BigEndian(data, offset + 8);
result.TableOffset = Utilities.ToInt64BigEndian(data, offset + 16);
result.HeaderVersion = Utilities.ToUInt32BigEndian(data, offset + 24);
result.MaxTableEntries = Utilities.ToInt32BigEndian(data, offset + 28);
result.BlockSize = Utilities.ToUInt32BigEndian(data, offset + 32);
result.Checksum = Utilities.ToUInt32BigEndian(data, offset + 36);
result.ParentUniqueId = Utilities.ToGuidBigEndian(data, offset + 40);
result.ParentTimestamp = Footer.EpochUtc.AddSeconds(Utilities.ToUInt32BigEndian(data, offset + 56));
result.ParentUnicodeName = Encoding.BigEndianUnicode.GetString(data, offset + 64, 512).TrimEnd('\0');
result.ParentLocators = new ParentLocator[8];
for (int i = 0; i < 8; ++i)
{
result.ParentLocators[i] = ParentLocator.FromBytes(data, offset + 576 + (i * 24));
}
return(result);
}
public static DynamicHeader FromBytes(byte[] data, int offset)
{
DynamicHeader result = new DynamicHeader();
result.Cookie = Utilities.BytesToString(data, offset, 8);
result.DataOffset = Utilities.ToInt64BigEndian(data, offset + 8);
result.TableOffset = Utilities.ToInt64BigEndian(data, offset + 16);
result.HeaderVersion = Utilities.ToUInt32BigEndian(data, offset + 24);
result.MaxTableEntries = Utilities.ToInt32BigEndian(data, offset + 28);
result.BlockSize = Utilities.ToUInt32BigEndian(data, offset + 32);
result.Checksum = Utilities.ToUInt32BigEndian(data, offset + 36);
result.ParentUniqueId = Utilities.ToGuidBigEndian(data, offset + 40);
result.ParentTimestamp = Footer.EpochUtc.AddSeconds(Utilities.ToUInt32BigEndian(data, offset + 56));
result.ParentUnicodeName = Encoding.BigEndianUnicode.GetString(data, offset + 64, 512).TrimEnd('\0');
result.ParentLocators = new ParentLocator[8];
for (int i = 0; i < 8; ++i)
{
result.ParentLocators[i] = ParentLocator.FromBytes(data, offset + 576 + (i * 24));
}
return result;
}
private static void InitializeDynamicInternal(Stream stream, long capacity, Geometry geometry, long blockSize)
{
if (blockSize > uint.MaxValue || blockSize < 0)
{
throw new ArgumentOutOfRangeException("blockSize", "Must be in the range 0 to uint.MaxValue");
}
if (geometry == null)
{
geometry = Geometry.FromCapacity(capacity);
}
Footer footer = new Footer(geometry, capacity, FileType.Dynamic);
footer.DataOffset = 512; // Offset of Dynamic Header
footer.UpdateChecksum();
byte[] footerBlock = new byte[512];
footer.ToBytes(footerBlock, 0);
DynamicHeader dynamicHeader = new DynamicHeader(-1, 1024 + 512, (uint)blockSize, capacity);
dynamicHeader.UpdateChecksum();
byte[] dynamicHeaderBlock = new byte[1024];
dynamicHeader.ToBytes(dynamicHeaderBlock, 0);
int batSize = (((dynamicHeader.MaxTableEntries * 4) + Utilities.SectorSize - 1) / Utilities.SectorSize) * Utilities.SectorSize;
byte[] bat = new byte[batSize];
for (int i = 0; i < bat.Length; ++i)
{
bat[i] = 0xFF;
}
stream.Position = 0;
stream.Write(footerBlock, 0, 512);
stream.Write(dynamicHeaderBlock, 0, 1024);
stream.Write(bat, 0, batSize);
stream.Write(footerBlock, 0, 512);
}
private static void InitializeDifferencingInternal(Stream stream, DiskImageFile parent, string parentAbsolutePath, string parentRelativePath, DateTime parentModificationTimeUtc)
{
Footer footer = new Footer(parent.Geometry, parent._footer.CurrentSize, FileType.Differencing);
footer.DataOffset = 512; // Offset of Dynamic Header
footer.OriginalSize = parent._footer.OriginalSize;
footer.UpdateChecksum();
byte[] footerBlock = new byte[512];
footer.ToBytes(footerBlock, 0);
long tableOffset = 512 + 1024; // Footer + Header
uint blockSize = (parent._dynamicHeader == null) ? DynamicHeader.DefaultBlockSize : parent._dynamicHeader.BlockSize;
DynamicHeader dynamicHeader = new DynamicHeader(-1, tableOffset, blockSize, footer.CurrentSize);
int batSize = (((dynamicHeader.MaxTableEntries * 4) + Utilities.SectorSize - 1) / Utilities.SectorSize) * Utilities.SectorSize;
dynamicHeader.ParentUniqueId = parent.UniqueId;
dynamicHeader.ParentTimestamp = parentModificationTimeUtc;
dynamicHeader.ParentUnicodeName = Utilities.GetFileFromPath(parentAbsolutePath);
dynamicHeader.ParentLocators[7].PlatformCode = ParentLocator.PlatformCodeWindowsAbsoluteUnicode;
dynamicHeader.ParentLocators[7].PlatformDataSpace = 512;
dynamicHeader.ParentLocators[7].PlatformDataLength = parentAbsolutePath.Length * 2;
dynamicHeader.ParentLocators[7].PlatformDataOffset = tableOffset + batSize;
dynamicHeader.ParentLocators[6].PlatformCode = ParentLocator.PlatformCodeWindowsRelativeUnicode;
dynamicHeader.ParentLocators[6].PlatformDataSpace = 512;
dynamicHeader.ParentLocators[6].PlatformDataLength = parentRelativePath.Length * 2;
dynamicHeader.ParentLocators[6].PlatformDataOffset = tableOffset + batSize + 512;
dynamicHeader.UpdateChecksum();
byte[] dynamicHeaderBlock = new byte[1024];
dynamicHeader.ToBytes(dynamicHeaderBlock, 0);
byte[] platformLocator1 = new byte[512];
Encoding.Unicode.GetBytes(parentAbsolutePath, 0, parentAbsolutePath.Length, platformLocator1, 0);
byte[] platformLocator2 = new byte[512];
Encoding.Unicode.GetBytes(parentRelativePath, 0, parentRelativePath.Length, platformLocator2, 0);
byte[] bat = new byte[batSize];
for (int i = 0; i < bat.Length; ++i)
{
bat[i] = 0xFF;
}
stream.Position = 0;
stream.Write(footerBlock, 0, 512);
stream.Write(dynamicHeaderBlock, 0, 1024);
stream.Write(bat, 0, batSize);
stream.Write(platformLocator1, 0, 512);
stream.Write(platformLocator2, 0, 512);
stream.Write(footerBlock, 0, 512);
}
internal DiskImageFileInfo(Footer footer, DynamicHeader header, Stream vhdStream)
{
_footer = footer;
_header = header;
_vhdStream = vhdStream;
}
private void CheckDynamicHeader()
{
long lastHeaderEnd = _footer.DataOffset + 512;
long pos = _footer.DataOffset;
while (pos != -1)
{
if (pos % 512 != 0)
{
ReportError("DynHeader: Unaligned header @{0}", pos);
}
_fileStream.Position = pos;
Header hdr = Header.FromStream(_fileStream);
if (hdr.Cookie == DynamicHeader.HeaderCookie)
{
if (_dynamicHeader != null)
{
ReportError("DynHeader: Duplicate dynamic header found");
}
_fileStream.Position = pos;
_dynamicHeader = DynamicHeader.FromStream(_fileStream);
if (pos + 1024 > lastHeaderEnd)
{
lastHeaderEnd = pos + 1024;
}
}
else
{
ReportWarning("DynHeader: Undocumented header found, with cookie '" + hdr.Cookie + "'");
if (pos + 512 > lastHeaderEnd)
{
lastHeaderEnd = pos + 1024;
}
}
pos = hdr.DataOffset;
}
if (_dynamicHeader == null)
{
ReportError("DynHeader: No dynamic header found");
return;
}
if (_dynamicHeader.TableOffset < lastHeaderEnd)
{
ReportError("DynHeader: BAT offset is before last header");
}
if (_dynamicHeader.TableOffset % 512 != 0)
{
ReportError("DynHeader: BAT offset is not sector aligned");
}
if (_dynamicHeader.HeaderVersion != 0x00010000)
{
ReportError("DynHeader: Unrecognized header version");
}
if (_dynamicHeader.MaxTableEntries != MathUtilities.Ceil(_footer.CurrentSize, _dynamicHeader.BlockSize))
{
ReportError("DynHeader: Max table entries is invalid");
}
if ((_dynamicHeader.BlockSize != Sizes.OneMiB * 2) && (_dynamicHeader.BlockSize != Sizes.OneKiB * 512))
{
ReportWarning("DynHeader: Using non-standard block size '" + _dynamicHeader.BlockSize + "'");
}
if (!Utilities.IsPowerOfTwo(_dynamicHeader.BlockSize))
{
ReportError("DynHeader: Block size is not a power of 2");
}
if (!_dynamicHeader.IsChecksumValid())
{
ReportError("DynHeader: Invalid checksum");
}
if (_footer.DiskType == FileType.Dynamic && _dynamicHeader.ParentUniqueId != Guid.Empty)
{
ReportWarning("DynHeader: Parent Id is not null for dynamic disk");
}
else if (_footer.DiskType == FileType.Differencing && _dynamicHeader.ParentUniqueId == Guid.Empty)
{
ReportError("DynHeader: Parent Id is null for differencing disk");
}
if (_footer.DiskType == FileType.Differencing && _dynamicHeader.ParentTimestamp > DateTime.UtcNow)
{
ReportWarning("DynHeader: Parent timestamp is greater than current time");
}
}
private void CheckDynamicHeader()
{
long lastHeaderEnd = _footer.DataOffset + 512;
long pos = _footer.DataOffset;
while (pos != -1)
{
if ((pos % 512) != 0)
{
ReportError("DynHeader: Unaligned header @{0}", pos);
}
_fileStream.Position = pos;
Header hdr = Header.FromStream(_fileStream);
if (hdr.Cookie == DynamicHeader.HeaderCookie)
{
if (_dynamicHeader != null)
{
ReportError("DynHeader: Duplicate dynamic header found");
}
_fileStream.Position = pos;
_dynamicHeader = DynamicHeader.FromStream(_fileStream);
if (pos + 1024 > lastHeaderEnd)
{
lastHeaderEnd = pos + 1024;
}
}
else
{
ReportWarning("DynHeader: Undocumented header found, with cookie '" + hdr.Cookie + "'");
if (pos + 512 > lastHeaderEnd)
{
lastHeaderEnd = pos + 1024;
}
}
pos = hdr.DataOffset;
}
if (_dynamicHeader == null)
{
ReportError("DynHeader: No dynamic header found");
return;
}
if (_dynamicHeader.TableOffset < lastHeaderEnd)
{
ReportError("DynHeader: BAT offset is before last header");
}
if ((_dynamicHeader.TableOffset % 512) != 0)
{
ReportError("DynHeader: BAT offset is not sector aligned");
}
if (_dynamicHeader.HeaderVersion != 0x00010000)
{
ReportError("DynHeader: Unrecognized header version");
}
if (_dynamicHeader.MaxTableEntries != Utilities.Ceil(_footer.CurrentSize, _dynamicHeader.BlockSize))
{
ReportError("DynHeader: Max table entries is invalid");
}
if ((_dynamicHeader.BlockSize != Sizes.OneMiB * 2) && (_dynamicHeader.BlockSize != Sizes.OneKiB * 512))
{
ReportWarning("DynHeader: Using non-standard block size '" + _dynamicHeader.BlockSize + "'");
}
if (!Utilities.IsPowerOfTwo(_dynamicHeader.BlockSize))
{
ReportError("DynHeader: Block size is not a power of 2");
}
if (!_dynamicHeader.IsChecksumValid())
{
ReportError("DynHeader: Invalid checksum");
}
if (_footer.DiskType == FileType.Dynamic && _dynamicHeader.ParentUniqueId != Guid.Empty)
{
ReportWarning("DynHeader: Parent Id is not null for dynamic disk");
}
else if (_footer.DiskType == FileType.Differencing && _dynamicHeader.ParentUniqueId == Guid.Empty)
{
ReportError("DynHeader: Parent Id is null for differencing disk");
}
if (_footer.DiskType == FileType.Differencing && _dynamicHeader.ParentTimestamp > DateTime.UtcNow)
{
ReportWarning("DynHeader: Parent timestamp is greater than current time");
}
}
private uint CalculateChecksum()
{
DynamicHeader copy = new DynamicHeader(this);
copy.Checksum = 0;
byte[] asBytes = new byte[1024];
copy.ToBytes(asBytes, 0);
uint checksum = 0;
foreach (uint value in asBytes)
{
checksum += value;
}
checksum = ~checksum;
return checksum;
}
private void ReadHeaders()
{
long pos = _footer.DataOffset;
while (pos != -1)
{
_fileStream.Position = pos;
Header hdr = Header.FromStream(_fileStream);
if (hdr.Cookie == DynamicHeader.HeaderCookie)
{
_fileStream.Position = pos;
_dynamicHeader = DynamicHeader.FromStream(_fileStream);
if (!_dynamicHeader.IsValid())
{
throw new IOException("Invalid Dynamic Disc Header");
}
}
pos = hdr.DataOffset;
}
}
internal DiskImageFileInfo(Footer footer, DynamicHeader header, Stream vhdStream)
{
_footer = footer;
_header = header;
_vhdStream = vhdStream;
}
private static void InitializeDynamicInternal(Stream stream, long capacity, Geometry geometry, long blockSize)
{
if (blockSize > uint.MaxValue || blockSize < 0)
{
throw new ArgumentOutOfRangeException("blockSize", "Must be in the range 0 to uint.MaxValue");
}
if (geometry == null)
{
geometry = Geometry.FromCapacity(capacity);
// Backwards compatibility - if the geometry isn't specified, make the actual capacity a
// multiple of the disk geometry's cylinder capacity.
long cylinderSize = geometry.BytesPerSector * (long)geometry.SectorsPerTrack * geometry.HeadsPerCylinder;
capacity = (capacity / cylinderSize) * cylinderSize;
}
Footer footer = new Footer(geometry, capacity, FileType.Dynamic);
footer.DataOffset = 512; // Offset of Dynamic Header
footer.UpdateChecksum();
byte[] footerBlock = new byte[512];
footer.ToBytes(footerBlock, 0);
DynamicHeader dynamicHeader = new DynamicHeader(-1, 1024 + 512, (uint)blockSize, capacity);
dynamicHeader.UpdateChecksum();
byte[] dynamicHeaderBlock = new byte[1024];
dynamicHeader.ToBytes(dynamicHeaderBlock, 0);
int batSize = (((dynamicHeader.MaxTableEntries * 4) + Utilities.SectorSize - 1) / Utilities.SectorSize) * Utilities.SectorSize;
byte[] bat = new byte[batSize];
for (int i = 0; i < bat.Length; ++i)
{
bat[i] = 0xFF;
}
stream.Position = 0;
stream.Write(footerBlock, 0, 512);
stream.Write(dynamicHeaderBlock, 0, 1024);
stream.Write(bat, 0, batSize);
stream.Write(footerBlock, 0, 512);
}
