public static unsafe NTHeaders *GetNtHeaders(byte *pBin)
{
// Bin is binary btw. Imo clearer than using peFile.
MS_DOS_Stub *stub = (MS_DOS_Stub *)(pBin);
if (stub->e_magic != IMAGE_DOS_SIGNATURE)
{
throw new FormatException("Error, Invalid file. DOS Signature is incorrect.");
}
NTHeaders *ntHeaders = (NTHeaders *)(pBin + stub->e_lfanew);
if (ntHeaders->MagicNumber != IMAGE_NT_PEHEADER_SIGNATURE)
{
throw new FormatException("Error, Invalid file. PE File signature incorrect.");
}
if (ntHeaders->optnHeader.magic == Magic.PE32)
{
throw new FormatException("Error, Invalid file. 32 Bit DLL's are not supported.");
}
else if (ntHeaders->optnHeader.magic != Magic.PE64)
{
throw new FormatException("Error, Invalid file. Optional header signature is incorrect.");
}
return(ntHeaders);
}
public static unsafe Dictionary <string, UInt32> dumpSymbolsFromFile(byte *pBin)
{
Dictionary <string, UInt32> ExportTable = new Dictionary <string, UInt32>();
NTHeaders *ntHeaders = GetNtHeaders(pBin);
IMAGE_EXPORT_DIRECTORY *exportDir = (IMAGE_EXPORT_DIRECTORY *)(pBin +
RVAtoOffset(ntHeaders->optnHeader.exportTable.VirtualAddress, ntHeaders, pBin));
if (ntHeaders->optnHeader.numberOfRvaAndSizes <= 0)
{
throw new ArgumentException("Error, This file has no exports.");
}
for (UInt32 i = 0; i < exportDir->NumberOfNames; i++)
{
UInt32 offset = (UInt32)RVAtoOffset((*(UInt32 *)(pBin + RVAtoOffset(exportDir->AddressOfFunctions, ntHeaders, pBin) + (i * sizeof(UInt32)))), ntHeaders, pBin);
UInt32 nameOffset = (UInt32)RVAtoOffset((UInt32)exportDir->AddressOfNames, ntHeaders, pBin) + (i * sizeof(UInt32));
string methodName = Marshal.PtrToStringAnsi((IntPtr)
(pBin + RVAtoOffset((*(UInt32 *)(pBin + nameOffset)), ntHeaders, pBin)));
ExportTable.Add(methodName, offset);
}
return(ExportTable);
}
// The offset is where the data is located in the file
// The RVA (Relative Virtual Address) is where the data is located relative to the start of the file when loaded into memory.
// The VA (Virtual Address) is the address of something in its own sandbox.
//
// These can be calculated by:
// VA = Offset + SectionHeader.VirtualAddress
// RVA = Offset + (SectionHeader.VirtualAddress - SectionTable.PointerToRawData)
//
public static unsafe UInt64 RVAtoOffset(UInt64 rva, NTHeaders *ntHeaders, byte *pBin)
{
MS_DOS_Stub *stub = (MS_DOS_Stub *)(pBin);
for (int i = 0; i < ntHeaders->FileHeader.numberOfSections; i++)
{
section_table *secTable = (section_table *)(pBin + stub->e_lfanew + sizeof(NTHeaders) + sizeof(section_table) * i);
if (secTable->virtualAddress <= rva && rva < secTable->virtualAddress + secTable->virtualSize)
{
return((UInt64)(rva) + secTable->pointerToRawData - secTable->virtualAddress);
}
}
throw new Exception("Erorr: Could not map RVA to Offset.");
}
