private IReadOnlyCollection <CabinetVolume> ReadVolumes(Stream cabinetStream)
{
var cabinetBinaryReader = new BinaryReader(cabinetStream);
List <CabinetVolume> volumes = new List <CabinetVolume>();
for (int i = 0; i < cabinetHeader.CabinetFileHeader.cFolders; i++)
{
CabinetVolume volume = new CabinetVolume()
{
CabinetFileVolume = cabinetStream.ReadStruct <CFFOLDER>(),
AdditionalApplicationData = cabinetHeader.VolumeAdditionalApplicationDataSize > 0 ? cabinetBinaryReader.ReadBytes(cabinetHeader.VolumeAdditionalApplicationDataSize) : new byte[0]
};
volumes.Add(volume);
if (volume.CabinetFileVolume.typeCompress != CFFOLDER.CFTYPECOMPRESS.TYPE_LZX &&
volume.CabinetFileVolume.typeCompress != CFFOLDER.CFTYPECOMPRESS.TYPE_MSZIP &&
volume.CabinetFileVolume.typeCompress != CFFOLDER.CFTYPECOMPRESS.TYPE_NONE)
{
throw new Exception("Unsupported Cabinet: Only LZX, MSZip and Store is currently supported");
}
if (volume.CabinetFileVolume.typeCompress == CFFOLDER.CFTYPECOMPRESS.TYPE_LZX)
{
if (volume.CabinetFileVolume.typeCompressOption < 15 || volume.CabinetFileVolume.typeCompressOption > 21)
{
throw new Exception("Unsupported Cabinet: LZX variable does not fall in supported ranges");
}
}
}
return(volumes);
}
public string ExtractFile(string FileName)
{
var destination = Path.GetTempFileName();
// Do the extraction
for (int volumeIndex = 0; volumeIndex < volumes.Count; volumeIndex++)
{
CabinetVolume volume = volumes.ElementAt(volumeIndex);
LzxDecoder lzx = null;
Inflater inf = null;
if (volume.CabinetFileVolume.typeCompress == CFFOLDER.CFTYPECOMPRESS.TYPE_LZX)
{
lzx = new LzxDecoder(volume.CabinetFileVolume.typeCompressOption);
}
if (volume.CabinetFileVolume.typeCompress == CFFOLDER.CFTYPECOMPRESS.TYPE_MSZIP)
{
inf = new Inflater(true);
}
List <(CFDATA dataStruct, int dataOffsetCabinet, int beginFolderOffset, int endFolderOffset, int index)> datas = new List <(CFDATA dataStruct, int dataOffsetCabinet, int beginFolderOffset, int endFolderOffset, int index)>();
List <(CabinetVolumeFile file, int startingBlock, int startingBlockOffset, int endingBlock, int endingBlockOffset)> fileBlockMap = new List <(CabinetVolumeFile file, int startingBlock, int startingBlockOffset, int endingBlock, int endingBlockOffset)>();
// Build Data Map
using (var cabinetFileStream = File.OpenRead(InputFile))
{
var cabinetBinaryReader = new BinaryReader(cabinetFileStream);
cabinetFileStream.Seek(volume.CabinetFileVolume.firstDataBlockOffset, SeekOrigin.Begin);
int offset = 0;
for (int i = 0; i < volume.CabinetFileVolume.dataBlockCount; i++)
{
CFDATA CabinetData = cabinetBinaryReader.BaseStream.ReadStruct <CFDATA>();
cabinetBinaryReader.BaseStream.Seek(cabinetHeader.DataAdditionalApplicationDataSize, SeekOrigin.Current);
datas.Add((CabinetData, (int)cabinetBinaryReader.BaseStream.Position, offset, offset + CabinetData.cbUncomp - 1, i));
cabinetBinaryReader.BaseStream.Seek(CabinetData.cbData, SeekOrigin.Current);
offset += CabinetData.cbUncomp;
}
// Build Block Map
foreach (CabinetVolumeFile file in files)
{
if (file.CabinetFileVolumeFile.iFolder != volumeIndex)
{
continue;
}
var FirstBlock = datas.First(x => x.beginFolderOffset <= file.CabinetFileVolumeFile.uoffFolderStart &&
file.CabinetFileVolumeFile.uoffFolderStart <= x.endFolderOffset);
var LastBlock = datas.First(x => x.beginFolderOffset <= (file.CabinetFileVolumeFile.uoffFolderStart + file.CabinetFileVolumeFile.cbFile - 1) &&
(file.CabinetFileVolumeFile.uoffFolderStart + file.CabinetFileVolumeFile.cbFile - 1) <= x.endFolderOffset);
int fileBeginFolderOffset = (int)file.CabinetFileVolumeFile.uoffFolderStart;
int fileEndFolderOffset = (int)file.CabinetFileVolumeFile.uoffFolderStart + (int)file.CabinetFileVolumeFile.cbFile - 1;
int start = (int)file.CabinetFileVolumeFile.uoffFolderStart - FirstBlock.beginFolderOffset;
int end = fileEndFolderOffset - LastBlock.beginFolderOffset;
fileBlockMap.Add((file, FirstBlock.index, start, LastBlock.index, end));
}
int fcount = 0;
for (int i = 0; i < volume.CabinetFileVolume.dataBlockCount; i++)
{
var CabinetData = datas[i];
cabinetBinaryReader.BaseStream.Seek(CabinetData.dataOffsetCabinet, SeekOrigin.Begin);
byte[] uncompressedDataBlock = new byte[CabinetData.dataStruct.cbUncomp];
byte[] compressedDataBlock = null;
if (volume.CabinetFileVolume.typeCompress == CFFOLDER.CFTYPECOMPRESS.TYPE_MSZIP)
{
var magic = cabinetBinaryReader.ReadBytes(2);
if (StructuralComparisons.StructuralComparer.Compare(magic, new byte[] { (byte)'C', (byte)'K' }) != 0)
{
throw new Exception("Bad Cabinet: Invalid Signature for MSZIP block");
}
compressedDataBlock = cabinetBinaryReader.ReadBytes(CabinetData.dataStruct.cbData - 2);
}
else
{
compressedDataBlock = cabinetBinaryReader.ReadBytes(CabinetData.dataStruct.cbData);
}
using (var uncompressedDataBlockStream = new MemoryStream(uncompressedDataBlock))
using (var compressedDataBlockStream = new MemoryStream(compressedDataBlock))
{
ExpandBlock(uncompressedDataBlockStream, compressedDataBlockStream, volume.CabinetFileVolume.typeCompress, lzx, inf);
}
foreach (CabinetVolumeFile file in files)
{
if (file.CabinetFileVolumeFile.iFolder != volumeIndex)
{
continue;
}
if (file.FileName.ToLower() != FileName.ToLower())
{
continue;
}
var mapping = fileBlockMap.First(x => x.file.FileName == file.FileName);
// This block contains this file
if (mapping.startingBlock <= i && i <= mapping.endingBlock)
{
int start = 0;
int end = CabinetData.dataStruct.cbUncomp - 1;
bool IsFirstBlock = mapping.startingBlock == i;
bool IsLastBlock = mapping.endingBlock == i;
if (IsFirstBlock)
{
start = mapping.startingBlockOffset;
}
if (IsLastBlock)
{
end = mapping.endingBlockOffset;
fcount++;
}
int count = end - start + 1;
using (var uncompressedDataStream = File.Open(destination, FileMode.OpenOrCreate))
{
uncompressedDataStream.Seek(0, SeekOrigin.End);
uncompressedDataStream.Write(uncompressedDataBlock, start, count);
}
}
}
}
}
}
return(destination);
}