Я нашел инструмент с именем PEDump (написанный Мэттом Пьетреком для своей книги) с исходным кодом, чтобы продемонстрировать, как получить размер информации для подписи.
Ниже приведен код, извлеченный из PEDump для моей цели,
// MakePtr is a macro that allows you to easily add to values (including
// pointers) together without dealing with C's pointer arithmetic. It
// essentially treats the last two parameters as DWORDs. The first
// parameter is used to typecast the result to the appropriate pointer type.
#define MakePtr( cast, ptr, addValue ) (cast)( (DWORD)(ptr) + (DWORD)(addValue))
// Names of the data directory elements that are defined
const char *ImageDirectoryNames[] = {
"EXPORT", "IMPORT", "RESOURCE", "EXCEPTION", "SECURITY", "BASERELOC",
"DEBUG", "COPYRIGHT", "GLOBALPTR", "TLS", "LOAD_CONFIG",
"BOUND_IMPORT", "IAT", // These two entries added for NT 3.51
"DELAY_IMPORT" }; // This entry added in NT 5
#define NUMBER_IMAGE_DIRECTORY_ENTRYS \
(sizeof(ImageDirectoryNames)/sizeof(char *))
HANDLE hFile = (HANDLE)_get_osfhandle(_fileno(getProgramFile()));
HANDLE hFileMapping = CreateFileMapping(hFile, NULL, PAGE_READONLY, 0, 0, NULL);
if ( hFileMapping == 0 )
{
printf("%s", "Couldn't open file mapping with CreateFileMapping()\n");
} else {
LPVOID lpFileBase = MapViewOfFile(hFileMapping, FILE_MAP_READ, 0, 0, 0);
if ( lpFileBase == 0 )
{
printf("%s", "Couldn't map view of file with MapViewOfFile()\n");
} else {
PIMAGE_DOS_HEADER dosHeader = (PIMAGE_DOS_HEADER)lpFileBase;
PIMAGE_FILE_HEADER pImgFileHdr = (PIMAGE_FILE_HEADER)lpFileBase;
// it's EXE file
if ( dosHeader->e_magic == IMAGE_DOS_SIGNATURE )
{
PIMAGE_NT_HEADERS pNTHeader;
DWORD base = (DWORD)dosHeader;
pNTHeader = MakePtr( PIMAGE_NT_HEADERS, dosHeader, dosHeader->e_lfanew );
PIMAGE_OPTIONAL_HEADER optionalHeader = (PIMAGE_OPTIONAL_HEADER)&pNTHeader->OptionalHeader;
for ( int i=0; i < optionalHeader->NumberOfRvaAndSizes; i++)
{
// DataDirectory[4] represents security directory
if ( 4 == i ) {
signingLength = optionalHeader->DataDirectory[i].Size;
break;
}
}
}
UnmapViewOfFile(lpFileBase);
}
CloseHandle(hFileMapping);
}