/// <summary>
/// </summary>
public void ReadHeaders()
{
if (!open)
{
throw new Exception("You must open image before trying to read it.");
}
dosHdr.Read(reader);
reader.BaseStream.Position = dosHdr.Lfanew;
ExeSignature peSig = (ExeSignature)reader.ReadUInt16();
if (peSig != ExeSignature.NT)
{
throw new Exception("Invalid image format: cannot find PE signature.");
}
peSig = (ExeSignature)reader.ReadUInt16();
if (peSig != ExeSignature.NT2)
{
throw new Exception("Invalid image format: cannot find PE signature.");
}
coffHdr.Read(reader);
peHdr.Read(reader);
sectionsPos = reader.BaseStream.Position;
ReadSections();
if (this.IsCLI)
{
reader.BaseStream.Position = RVAToVA(peHdr.CLIHdrDir.virtAddr);
corHdr.Read(reader);
mdRoot = new MetaDataRoot(this);
reader.BaseStream.Position = RVAToVA(corHdr.MetaData.virtAddr);
mdRoot.Read(reader);
}
}
public static uint Calc(string peFile)
{
uint res = 0;
FileInfo pe = new FileInfo(peFile);
if (!pe.Exists)
{
throw new Exception("CheckSum : Invalid file path.");
}
using (BinaryReader reader = new BinaryReader(pe.OpenRead())) {
if (!reader.BaseStream.CanSeek)
{
throw new Exception("Can't seek.");
}
DOSHeader dosHdr = new DOSHeader();
COFFHeader coffHdr = new COFFHeader();
PEHeader peHdr = new PEHeader();
dosHdr.Read(reader);
reader.BaseStream.Position = dosHdr.Lfanew;
ExeSignature peSig = (ExeSignature)reader.ReadUInt16();
if (peSig != ExeSignature.NT)
{
throw new BadImageException("Checksum : Invalid image format, cannot find PE signature.");
}
peSig = (ExeSignature)reader.ReadUInt16();
if (peSig != ExeSignature.NT2)
{
throw new BadImageException("Checksum : Invalid image format, cannot find PE signature.");
}
coffHdr.Read(reader);
peHdr.Read(reader);
uint oldSum = peHdr.CheckSum;
reader.BaseStream.Position = 0;
long len = pe.Length;
long whole = len >> 1;
uint sum = 0;
uint hi, lo;
for (long i = whole; --i >= 0;)
{
sum += reader.ReadUInt16();
hi = sum >> 16;
if (hi != 0)
{
sum = hi + (sum & 0xFFFF);
}
}
if ((len & 1L) != 0)
{
sum += (uint)reader.ReadByte();
hi = sum >> 16;
if (hi != 0)
{
sum = hi + (sum & 0xFFFF);
}
}
// fix low word of checksum
lo = oldSum & 0xFFFF;
if ((sum & 0xFFFF) >= lo)
{
sum -= lo;
}
else
{
sum = (((sum & 0xFFFF) - lo) & 0xFFFF) - 1;
}
// fix high word of checksum
hi = oldSum >> 16;
if ((sum & 0xFFFF) >= hi)
{
sum -= hi;
}
else
{
sum = (((sum & 0xFFFF) - hi) & 0xFFFF) - 1;
}
}
return(res);
}
