private ExecutableImage(Stream sourceStream, bool ownStream)
{
_disposed = false;
_stream = sourceStream;
_own_stream = ownStream;
_calc = null;
_dos_header = null;
_dos_stub = null;
_nt_headers = null;
_section_table = null;
_sections = null;
_is_32bit = false;
_is_64bit = false;
_is_clr = false;
_is_signed = false;
Load();
}
private ExeReader(Stream sourceStream, bool ownStream)
{
if (!sourceStream.CanRead)
throw new IOException("Cannot read from stream.");
if (!sourceStream.CanSeek)
throw new IOException("Cannot seek in stream.");
_disposed = false;
_stream = sourceStream;
_own_stream = ownStream;
_dos_header = null;
_dos_stub = null;
_nt_headers = null;
_section_table = null;
_sections = null;
is_32bit = false;
is_64bit = false;
is_clr = false;
}
private void Load()
{
string error_message = String.Empty;
PreloadedInformation preload_info = TryPreload(_stream,out error_message);
if (preload_info == null)
throw new ExecutableImageException(error_message);
ulong image_base = 0;
if (preload_info.OptHeader32 != null)
image_base = preload_info.OptHeader32.Value.ImageBase;
if (preload_info.OptHeader64 != null)
image_base = preload_info.OptHeader64.Value.ImageBase;
_dos_header = new DOSHeader(this,preload_info.DOSHeader,image_base);
_dos_stub = new DOSStub(this,preload_info.StubOffset,preload_info.StubSize,image_base);
FileHeader file_header = new FileHeader(this,preload_info.FileHeader,_dos_stub.Location.FileOffset + _dos_stub.Location.FileSize + 4,image_base);
OptionalHeader opt_header;
if (preload_info.Is32Bit)
{
opt_header = new OptionalHeader32(this,preload_info.OptHeader32.Value,file_header.Location.FileOffset + file_header.Location.FileSize,image_base);
}
else
{
opt_header = new OptionalHeader64(this,preload_info.OptHeader64.Value,file_header.Location.FileOffset + file_header.Location.FileSize,image_base);
}
DataDirectoryCollection data_dirs = new DataDirectoryCollection(this,opt_header,preload_info.DataDirectories);
_nt_headers = new NTHeaders(this,file_header.Location.FileOffset - 4,image_base,file_header,opt_header,data_dirs);
_section_table = new SectionTable(this,preload_info.SectionHeaders,_nt_headers.Location.FileOffset + _nt_headers.Location.FileSize,image_base);
_sections = new Sections(_section_table);
_is_32bit = preload_info.Is32Bit;
_is_64bit = preload_info.Is64Bit;
_is_clr = preload_info.IsCLR;
_is_signed = preload_info.IsSigned;
}
private async Task LoadAsync()
{
if (!_stream.CanSeek)
{
throw new PortableExecutableImageException(this, "Cannot seek in stream.");
}
if (!_stream.CanRead)
{
throw new PortableExecutableImageException(this, "Cannot read from stream.");
}
IMAGE_DOS_HEADER dosHeader;
try
{
dosHeader = await _stream.ReadStructAsync <IMAGE_DOS_HEADER>(DOSHeader.Size).ConfigureAwait(false);
}
catch (Exception ex)
{
throw new PortableExecutableImageException(this, "Cannot read DOS header from stream.", ex);
}
if (dosHeader.e_magic != DOSHeader.DOS_MAGIC_MZ)
{
throw new PortableExecutableImageException(this, "Incorrect magic number specified in DOS header.");
}
if (dosHeader.e_lfanew == 0)
{
throw new PortableExecutableImageException(this, "No new header location specified in DOS header, most likely a 16-bit executable.");
}
if (dosHeader.e_lfanew >= (256 * (1024 * 1024)))
{
throw new PortableExecutableImageException(this, "New header location specified in MS-DOS header is beyond 256mb boundary (see RtlImageNtHeaderEx).");
}
if (dosHeader.e_lfanew % 4 != 0)
{
throw new PortableExecutableImageException(this, "New header location specified in MS-DOS header is not properly aligned.");
}
if (dosHeader.e_lfanew < DOSHeader.Size)
{
throw new PortableExecutableImageException(this, "New header location specified is invalid.");
}
var stubOffset = DOSHeader.Size;
var stubSize = dosHeader.e_lfanew - DOSHeader.Size;
var stubRead = await _stream.SkipBytesAsync(stubSize).ConfigureAwait(false);
if (stubRead < stubSize)
{
throw new PortableExecutableImageException(this, "Could not read DOS stub from stream.");
}
_stream.Seek(dosHeader.e_lfanew, SeekOrigin.Begin);
var ntOffset = _stream.Position;
uint peSig;
try
{
peSig = await _stream.ReadUInt32Async().ConfigureAwait(false);
}
catch (Exception ex)
{
throw new PortableExecutableImageException(this, "Could not read PE signature from stream.", ex);
}
if (peSig != NTHeaders.PE_MAGIC_MZ)
{
throw new PortableExecutableImageException(this, "Incorrect PE signature found in NT Header.");
}
IMAGE_FILE_HEADER fileHdr;
try
{
fileHdr = await _stream.ReadStructAsync <IMAGE_FILE_HEADER>(FileHeader.Size).ConfigureAwait(false);
}
catch (Exception ex)
{
throw new PortableExecutableImageException(this, "Could not read NT Header from stream.", ex);
}
ushort magic = 0;
try
{
magic = await _stream.ReadUInt16Async().ConfigureAwait(false);
}
catch (Exception ex)
{
throw new PortableExecutableImageException(this, "Could not read Optional Header magic number from stream.", ex);
}
Is32Bit = (magic == (ushort)MagicType.PE32);
Is64Bit = (magic == (ushort)MagicType.PE32plus);
if (!Is32Bit && !Is64Bit)
{
throw new PortableExecutableImageException(this, "Unknown PE type.");
}
byte[] optionalHeaderBytes;
try
{
var optionalHeaderSize = (Is32Bit ? Utils.SizeOf <IMAGE_OPTIONAL_HEADER32>() : Utils.SizeOf <IMAGE_OPTIONAL_HEADER64>());
optionalHeaderBytes = await _stream.ReadBytesAsync(optionalHeaderSize).ConfigureAwait(false);
}
catch (Exception ex)
{
throw new PortableExecutableImageException(this, "Could not read Optional Header from stream.", ex);
}
IMAGE_OPTIONAL_HEADER32 optionalHeader32 = new IMAGE_OPTIONAL_HEADER32();
IMAGE_OPTIONAL_HEADER64 optionalHeader64 = new IMAGE_OPTIONAL_HEADER64();
var dirCount = 0;
if (Is32Bit)
{
optionalHeader32 = Utils.Read <IMAGE_OPTIONAL_HEADER32>(optionalHeaderBytes);
dirCount = optionalHeader32.NumberOfRvaAndSizes.ToInt32();
}
else
{
optionalHeader64 = Utils.Read <IMAGE_OPTIONAL_HEADER64>(optionalHeaderBytes);
dirCount = optionalHeader64.NumberOfRvaAndSizes.ToInt32();
}
var dataDirs = new IMAGE_DATA_DIRECTORY[dirCount];
var dataDirSize = Utils.SizeOf <IMAGE_DATA_DIRECTORY>();
for (var i = 0; i < dirCount; i++)
{
try
{
dataDirs[i] = await _stream.ReadStructAsync <IMAGE_DATA_DIRECTORY>(dataDirSize).ConfigureAwait(false);
}
catch (Exception ex)
{
throw new PortableExecutableImageException(this, "Could not read data directory from stream.", ex);
}
}
var sectionTableEntrySize = Utils.SizeOf <IMAGE_SECTION_HEADER>();
var sectionTable = new IMAGE_SECTION_HEADER[fileHdr.NumberOfSections];
for (var i = 0; i < fileHdr.NumberOfSections; i++)
{
try
{
sectionTable[i] = await _stream.ReadStructAsync <IMAGE_SECTION_HEADER>(sectionTableEntrySize).ConfigureAwait(false);
}
catch (Exception ex)
{
throw new PortableExecutableImageException(this, "Could not read section table entry from stream.", ex);
}
}
IsCLR = false;
var clrIndex = (int)DataDirectoryType.CLRRuntimeHeader;
if (clrIndex >= 0 && clrIndex <= (dataDirs.Length - 1))
{
var clrDirectory = dataDirs[clrIndex];
if (clrDirectory.VirtualAddress > 0 && clrDirectory.Size > 0)
{
IsCLR = true;
}
}
IsSigned = false;
var certIndex = (int)DataDirectoryType.CertificateTable;
if (certIndex >= 0 && certIndex <= (dataDirs.Length - 1))
{
var certDirectory = dataDirs[certIndex];
if (certDirectory.VirtualAddress > 0 && certDirectory.Size > 0)
{
IsSigned = true;
}
}
var imageBase = (Is32Bit ? optionalHeader32.ImageBase : optionalHeader64.ImageBase);
DOSHeader = new DOSHeader(this, dosHeader, imageBase);
DOSStub = new DOSStub(this, stubOffset.ToUInt64(), stubSize.ToUInt32(), imageBase);
var fileHeader = new FileHeader(this, fileHdr, DOSStub.Location.FileOffset + DOSStub.Location.FileSize + 4, imageBase);
OptionalHeader optionalHeader;
if (Is32Bit)
{
optionalHeader = new OptionalHeader32(this, optionalHeader32, fileHeader.Location.FileOffset + fileHeader.Location.FileSize, imageBase, magic);
}
else
{
optionalHeader = new OptionalHeader64(this, optionalHeader64, fileHeader.Location.FileOffset + fileHeader.Location.FileSize, imageBase, magic);
}
var dataDirectories = new DataDirectories(this, optionalHeader, dataDirs);
NTHeaders = new NTHeaders(this, ntOffset.ToUInt64(), imageBase, fileHeader, optionalHeader, dataDirectories);
SectionTable = new SectionTable(this, sectionTable, NTHeaders.Location.FileOffset + NTHeaders.Location.FileSize, imageBase);
Sections = new Sections(this, SectionTable);
}
private void LoadDOSStub()
{
if (_dos_header == null)
LoadDOSHeader();
long offset = _dos_header.Location.Offset + _dos_header.Location.Size;
int size = _dos_header.FileAddressNewHeader - DOSHeader.Size;
if ((offset + size) > _stream.Length)
throw new ExeReaderException("Cannot read beyond end of stream.");
StreamLocation location = new StreamLocation(offset,size);
_dos_stub = new DOSStub(this,location);
}