private static void FreePointerList(POINTER_LIST head, CustomFreeFunc freeMemory, void* userdata)
{
POINTER_LIST node = head;
while (node != null)
{
POINTER_LIST next;
freeMemory(node.address, null, MEM_RELEASE, userdata);
next = node.next;
node = next;
}
}
internal static MEMORYMODULE MemoryLoadLibraryEx(void* data, void* size, CustomAllocFunc allocMemory, CustomFreeFunc freeMemory, CustomLoadLibraryFunc loadLibrary, CustomGetProcAddressFunc getProcAddress, CustomFreeLibraryFunc freeLibrary, void* userdata)
{
MEMORYMODULE result = null;
IMAGE_DOS_HEADER* dos_header;
void* old_header;
byte* code, headers;
void* locationDelta;
SYSTEM_INFO sysInfo;
IMAGE_SECTION_HEADER* section;
uint i;
void* optionalSectionSize;
void* lastSectionEnd = null;
void* alignedImageSize;
POINTER_LIST blockedMemory = null;
if (!CheckSize(size, (void*)IMAGE_DOS_HEADER.UnmanagedSize))
return null;
dos_header = (IMAGE_DOS_HEADER*)data;
if (dos_header->e_magic != IMAGE_DOS_SIGNATURE)
return null;
if (!CheckSize(size, (void*)(dos_header->e_lfanew + (WIN64 ? IMAGE_NT_HEADERS64.UnmanagedSize : IMAGE_NT_HEADERS32.UnmanagedSize))))
return null;
old_header = &((byte*)data)[dos_header->e_lfanew];
if ((WIN64 ? ((IMAGE_NT_HEADERS64*)old_header)->Signature : ((IMAGE_NT_HEADERS32*)old_header)->Signature) != IMAGE_NT_SIGNATURE)
return null;
if ((WIN64 ? ((IMAGE_NT_HEADERS64*)old_header)->FileHeader.Machine : ((IMAGE_NT_HEADERS32*)old_header)->FileHeader.Machine) != HOST_MACHINE)
return null;
if (((WIN64 ? ((IMAGE_NT_HEADERS64*)old_header)->OptionalHeader.SectionAlignment : ((IMAGE_NT_HEADERS32*)old_header)->OptionalHeader.SectionAlignment) & 1) != 0)
// Only support section alignments that are a multiple of 2
return null;
section = IMAGE_FIRST_SECTION(old_header);
optionalSectionSize = (void*)((WIN64 ? ((IMAGE_NT_HEADERS64*)old_header)->OptionalHeader.SectionAlignment : ((IMAGE_NT_HEADERS32*)old_header)->OptionalHeader.SectionAlignment));
for (i = 0; i < (WIN64 ? ((IMAGE_NT_HEADERS64*)old_header)->FileHeader.NumberOfSections : ((IMAGE_NT_HEADERS32*)old_header)->FileHeader.NumberOfSections); i++, section++)
{
void* endOfSection;
if (section->SizeOfRawData == 0)
{
// Section without data in the DLL
endOfSection = (void*)(section->VirtualAddress + (ulong)optionalSectionSize);
}
else
{
endOfSection = (void*)(section->VirtualAddress + (ulong)section->SizeOfRawData);
}
if ((ulong)endOfSection > (ulong)lastSectionEnd)
lastSectionEnd = endOfSection;
}
GetNativeSystemInfo(&sysInfo);
alignedImageSize = AlignValueUp((void*)(WIN64 ? ((IMAGE_NT_HEADERS64*)old_header)->OptionalHeader.SizeOfImage : ((IMAGE_NT_HEADERS32*)old_header)->OptionalHeader.SizeOfImage), (void*)sysInfo.dwPageSize);
if (alignedImageSize != AlignValueUp(lastSectionEnd, (void*)sysInfo.dwPageSize))
return null;
// reserve memory for image of library
// XXX: is it correct to commit the complete memory region at once?
// calling DllEntry raises an exception if we don't...
code = (byte*)allocMemory((void*)(WIN64 ? ((IMAGE_NT_HEADERS64*)old_header)->OptionalHeader.ImageBase : ((IMAGE_NT_HEADERS32*)old_header)->OptionalHeader.ImageBase), alignedImageSize, MEM_RESERVE | MEM_COMMIT, PAGE_READWRITE, userdata);
if (code == null)
{
// try to allocate memory at arbitrary position
code = (byte*)allocMemory(null, alignedImageSize, MEM_RESERVE | MEM_COMMIT, PAGE_READWRITE, userdata);
if (code == null)
return null;
}
if (WIN64)
{
// Memory block may not span 4 GB boundaries.
while ((ulong)code >> 32 < ((ulong)code + (ulong)alignedImageSize) >> 32)
{
POINTER_LIST node = new POINTER_LIST
{
next = blockedMemory,
address = code
};
blockedMemory = node;
code = (byte*)allocMemory(null, alignedImageSize, MEM_RESERVE | MEM_COMMIT, PAGE_READWRITE, userdata);
if (code == null)
{
FreePointerList(blockedMemory, freeMemory, userdata);
return null;
}
}
}
result = new MEMORYMODULE
{
codeBase = code,
isDLL = ((WIN64 ? ((IMAGE_NT_HEADERS64*)old_header)->FileHeader.Characteristics : ((IMAGE_NT_HEADERS32*)old_header)->FileHeader.Characteristics) & IMAGE_FILE_DLL) != 0,
alloc = allocMemory,
free = freeMemory,
loadLibrary = loadLibrary,
getProcAddress = getProcAddress,
freeLibrary = freeLibrary,
userdata = userdata,
pageSize = sysInfo.dwPageSize
};
if (WIN64)
result.blockedMemory = blockedMemory;
if (!CheckSize(size, (void*)(WIN64 ? ((IMAGE_NT_HEADERS64*)old_header)->OptionalHeader.SizeOfHeaders : ((IMAGE_NT_HEADERS32*)old_header)->OptionalHeader.SizeOfHeaders)))
goto error;
// commit memory for headers
headers = (byte*)allocMemory(code, (void*)(WIN64 ? ((IMAGE_NT_HEADERS64*)old_header)->OptionalHeader.SizeOfHeaders : ((IMAGE_NT_HEADERS32*)old_header)->OptionalHeader.SizeOfHeaders), MEM_COMMIT, PAGE_READWRITE, userdata);
// copy PE header to code
memcpy(headers, dos_header, (void*)(WIN64 ? ((IMAGE_NT_HEADERS64*)old_header)->OptionalHeader.SizeOfHeaders : ((IMAGE_NT_HEADERS32*)old_header)->OptionalHeader.SizeOfHeaders));
result.headers = &headers[dos_header->e_lfanew];
// update position
if (WIN64)
((IMAGE_NT_HEADERS64*)result.headers)->OptionalHeader.ImageBase = (ulong)code;
else
((IMAGE_NT_HEADERS32*)result.headers)->OptionalHeader.ImageBase = (uint)code;
// copy sections from DLL file block to new memory location
if (!CopySections((byte*)data, size, old_header, result))
goto error;
// adjust base address of imported data
locationDelta = (void*)((WIN64 ? ((IMAGE_NT_HEADERS64*)result.headers)->OptionalHeader.ImageBase : ((IMAGE_NT_HEADERS32*)result.headers)->OptionalHeader.ImageBase) - (WIN64 ? ((IMAGE_NT_HEADERS64*)old_header)->OptionalHeader.ImageBase : ((IMAGE_NT_HEADERS32*)old_header)->OptionalHeader.ImageBase));
if ((ulong)locationDelta != 0)
result.isRelocated = PerformBaseRelocation(result, locationDelta);
else
result.isRelocated = true;
// load required dlls and adjust function table of imports
if (!BuildImportTable(result))
goto error;
// mark memory pages depending on section headers and release
// sections that are marked as "discardable"
if (!FinalizeSections(result))
goto error;
// TLS callbacks are executed BEFORE the main loading
if (!ExecuteTLS(result))
goto error;
// get entry point of loaded library
if ((WIN64 ? ((IMAGE_NT_HEADERS64*)result.headers)->OptionalHeader.AddressOfEntryPoint : ((IMAGE_NT_HEADERS32*)result.headers)->OptionalHeader.AddressOfEntryPoint) != 0)
{
if (result.isDLL)
{
DllEntryProc DllEntry = (DllEntryProc)Marshal.GetDelegateForFunctionPointer((IntPtr)(code + (WIN64 ? ((IMAGE_NT_HEADERS64*)result.headers)->OptionalHeader.AddressOfEntryPoint : ((IMAGE_NT_HEADERS32*)result.headers)->OptionalHeader.AddressOfEntryPoint)), typeof(DllEntryProc));
// notify library about attaching to process
bool successfull = DllEntry(code, DLL_PROCESS_ATTACH, null);
if (!successfull)
goto error;
result.initialized = true;
}
else
result.exeEntry = (ExeEntryProc)Marshal.GetDelegateForFunctionPointer((IntPtr)(code + (WIN64 ? ((IMAGE_NT_HEADERS64*)result.headers)->OptionalHeader.AddressOfEntryPoint : ((IMAGE_NT_HEADERS32*)result.headers)->OptionalHeader.AddressOfEntryPoint)), typeof(ExeEntryProc));
}
else
result.exeEntry = null;
return result;
error:
// cleanup
MemoryFreeLibrary(result);
return null;
}