/// <summary>
/// Updates the physical location of all sections, and updates the amount of initialized data
/// </summary>
public void UpdatePhysicalLayout()
{
uint fileAlignment, filePosition;
switch (optionalStandard.Magic)
{
case IMAGE_OPTIONAL_HEADER_STANDARD.MAGIC_PE32:
fileAlignment = optionalHeader32.FileAlignment;
filePosition = optionalHeader32.SizeOfHeaders;
break;
case IMAGE_OPTIONAL_HEADER_STANDARD.MAGIC_ROM:
throw new NotSupportedException();
case IMAGE_OPTIONAL_HEADER_STANDARD.MAGIC_PE32PLUS:
fileAlignment = optionalHeader32plus.FileAlignment;
filePosition = optionalHeader32plus.SizeOfHeaders;
break;
default:
throw new ArgumentException();
}
uint initializedDataSize = 0;
/* Layout the sections in physical order */
foreach (var s in sections)
{
if (s.ContributesToFileSize)
{
//TODO use null coalecing operator somehow
if (s.Data != null)
{
s.RawSize = PEUtility.AlignUp((uint)s.Data.Length, fileAlignment);
}
else
{
s.RawSize = PEUtility.AlignUp(s.RawSize, fileAlignment);
}
s.PhysicalAddress = filePosition;
filePosition += s.RawSize;
initializedDataSize += s.RawSize;
}
}
optionalStandard.SizeOfInitializedData = initializedDataSize;
}
public void UpdateVirtualLayout(uint initialVirtualAddress = StartingVirtualAddress)
{
uint virtualAlignment;
switch (optionalStandard.Magic)
{
case IMAGE_OPTIONAL_HEADER_STANDARD.MAGIC_PE32:
virtualAlignment = optionalHeader32.SectionAlignment;
break;
case IMAGE_OPTIONAL_HEADER_STANDARD.MAGIC_ROM:
throw new NotSupportedException();
case IMAGE_OPTIONAL_HEADER_STANDARD.MAGIC_PE32PLUS:
virtualAlignment = optionalHeader32plus.SectionAlignment;
break;
default:
throw new ArgumentException();
}
/*
* Fix up virtual addresses of the sections.
* We start at 0x1000 (seems to be the convention)
* Text should come first, then followed by data, then reloc
* As we encounter certain sections, we need to update
* special fields (data directory entries etc.).
*/
uint virtualPosition = initialVirtualAddress;
bool dataSectionEncountered = false;
foreach (var s in sections)
{
//update optional header
switch (s.Name)
{
case TEXT:
optionalStandard.BaseOfCode = virtualPosition;
break;
case RDATA:
case DATA:
//PE32 headers want to know where the data starts
if (optionalStandard.Magic == IMAGE_OPTIONAL_HEADER_STANDARD.MAGIC_PE32 && !dataSectionEncountered)
{
dataSectionEncountered = true;
optionalHeader32.BaseOfData = virtualPosition;
}
break;
}
//update virtual address
if (s.VirtualAddress != virtualPosition)
{
switch (s.Name)
{
case RSRC:
ResourceTable res;
using (var ms = new MemoryStream(s.Data))
{
//need to give it the original RVA 'cause that's important
res = new ResourceTable(ms, s.VirtualAddress);
}
res.UpdateVirtualAddress(virtualPosition);
//this is only safe because all I've done is changed the virtual address and reserialized the data
//this means the data size can only go DOWN (because of alignment not being included)
//do not repeat this anywhere else where the data gets changed
s.Data = res.ToArray();
goto default;
default:
s.VirtualAddress = virtualPosition;
break;
}
}
//update size
if (s.HasUninitializedData)
{
// Leave uninitialized data sizes untouched, their raw size is 0
}
else if (s.HasInitializedData && s.HasCode)
{
//TODO really not sure why this is here...
// It is possible for the virtual size to be greater than the size of raw data
// Leave the virtual size untouched if this is the case
if (s.VirtualSize <= s.RawSize)
{
s.VirtualSize = (uint)s.Data.Length;
}
}
virtualPosition += PEUtility.AlignUp(s.VirtualSize, virtualAlignment);
}
/* Total virtual size is the final virtual address, which includes the initial virtual offset. */
if (optionalStandard.Magic == IMAGE_OPTIONAL_HEADER_STANDARD.MAGIC_PE32)
{
optionalHeader32.SizeOfImage = virtualPosition;
}
else
{
optionalHeader32plus.SizeOfImage = virtualPosition;
}
}
/// <summary>
/// Layout contents of PE file, updating headers and order sections.
/// </summary>
/// <returns>Returns bool describing if layout succeeded.</returns>
public bool Layout()
{
uint virtualAlignment = optionalHeader.SectionAlignment;
uint fileAlignment = optionalHeader.FileAlignment;
uint totalSize = 0;
uint initializedDataSize = 0;
totalSize += optionalHeader.SizeOfHeaders;
/* Calculate total physical size required */
foreach (PESection s in sections)
{
totalSize += PEUtility.AlignUp((uint)s.Data.Length, fileAlignment);
}
/* Layout the sections in physical order */
uint filePosition = optionalHeader.SizeOfHeaders;
sections.Sort(new SectionPhysicalComparer());
foreach (PESection s in sections)
{
if (s.ContributesToFileSize())
{
s.RawSize = PEUtility.AlignUp((uint)s.Data.Length, fileAlignment);
s.PhysicalAddress = filePosition;
filePosition += s.RawSize;
initializedDataSize += PEUtility.AlignUp((uint)s.Data.Length, fileAlignment);
}
break;
}
optionalHeader.SizeOfInitializedData = initializedDataSize;
/*
* Fix up virtual addresses of the sections.
* We start at 0x1000 (seems to be the convention)
* Text should come first, then followed by data, then reloc
* As we encounter certain sections, we need to update
* special fields (data directory entries etc.).
*/
uint virtAddr = 0x1000;
bool dataSectionEncountered = false;
sections.Sort(new SectionVirtualComparer());
foreach (PESection s in sections)
{
if (s.Name == ".text")
{
optionalHeader.BaseOfCode = virtAddr;
}
if (!dataSectionEncountered &&
((s.Name == ".data") || (s.Name == ".rdata")))
{
dataSectionEncountered = true;
optionalHeader.BaseOfData = virtAddr;
}
if (s.Name == ".rdata")
{
dataDirectories.debug.VirtualAddress = virtAddr;
}
if (s.Name == ".reloc")
{
dataDirectories.baseReloc.VirtualAddress = virtAddr;
}
s.VirtualAddress = virtAddr;
if (s.HasUninitializedData)
{
// Leave uninitialized data sizes untouched, their raw size is 0
virtAddr += PEUtility.AlignUp(s.VirtualSize, virtualAlignment);
}
else if (s.HasInitializedData && s.HasCode)
{
// It is possible for the virtual size to be greater than the size of raw data
// Leave the virtual size untouched if this is the case
if (s.VirtualSize > s.RawSize)
{
virtAddr += PEUtility.AlignUp(s.VirtualSize, virtualAlignment);
}
else
{
s.VirtualSize = (uint)s.Data.Length;
virtAddr += PEUtility.AlignUp((uint)s.Data.Length, virtualAlignment);
}
}
break;
}
/* Total virtual size is the final virtual address, which includes the initial virtual offset. */
optionalHeader.SizeOfImage = virtAddr;
/* Serialize and write the header contents */
Serialize(totalSize);
return(true);
}
