我正在尝试在C中构建一个PE查看器,如果我尝试在“导入目录表”中输出库的名称,它似乎会崩溃.看来我没有得到程序使用的DLL的正确指针.
HANDLE handle = CreateFile("messageBox.exe",GENERIC_READ,OPEN_EXISTING,FILE_ATTRIBUTE_NORMAL,0);
DWORD size = GetFileSize(handle,NULL);
PVOID virtualpointer = VirtualAlloc(NULL,size,MEM_COMMIT,PAGE_READWRITE);
state = ReadFile(handle,virtualpointer,&byteread,NULL);
CloseHandle(handle);
PIMAGE_NT_HEADERS ntheaders = PIMAGE_NT_HEADERS(PCHAR(vpointer) +
PIMAGE_DOS_HEADER(vpointer)->e_lfanew);
handle = GetCurrentProcess();
DWORD EntryAddr = ntheaders->OptionalHeader.ImageBase +
ntheaders->OptionalHeader.AddressOfEntryPoint;
DWORD importdir =
(DWORD) &(ntheaders->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_IMPORT]);
DWORD va = (DWORD)(ntheaders->OptionalHeader.ImageBase) +
((PIMAGE_DATA_DIRECTORY)dwValueB)->VirtualAddress;
LPSTR libname[128];
int i =0;
while(((PIMAGE_IMPORT_DESCRIPTOR)dwValueC)->Name)
{
// get DLL name
libname[i] = (LPSTR)(nt->OptionalHeader.ImageBase +
((PIMAGE_IMPORT_DESCRIPTOR)dwValueC)->Name);
i++;
}
解决方法
要在“导入目录表”中读取库的名称,可以执行以下操作：
>获取文件的内存映射基址.
>获取指向IMAGE_NT_HEADERS结构的指针.
>获取指向IMAGE_SECTION_HEADER结构的指针.
> DataDirectory是OptionalHeader的最后128个字节,而后者又是PE头IMAGE_NT_HEADERS的最终成员.
该结构有2个成员,包含数据结构的位置和大小.
如果要查找有关dll名称的信息,首先要从数据目录中找到导入目录的RVA(相对虚拟地址),在原始部分数据中找到该地址,现在您有一个IMAGE_IMPORT_DESCRIPTOR数组.通过检查Name字段指向的字符串,获取与映射图像相关的此数组的成员.
我不会描述可移植可执行文件格式的结构,但您可以查看以下链接：
Peering Inside the PE
Microsoft Systems Journal
你的代码中的一些变量没有被声明,这是令人困惑的,但坚持你的骨架代码我写它,以便它符合你的问题.
DWORD Rva2Offset(DWORD rva,PIMAGE_SECTION_HEADER psh,PIMAGE_NT_HEADERS pnt);
int _tmain(int argc,_TCHAR* argv[])
{
LPCWSTR fNmae=L"C:\\Windows\\system32\\notepad.exe";
HANDLE handle=CreateFile(fNmae/*"messageBox.exe"*/,0);
DWORD byteread,size=GetFileSize(handle,NULL);
PVOID virtualpointer=VirtualAlloc(NULL,PAGE_READWRITE);
ReadFile(handle,NULL);
CloseHandle(handle);
// Get pointer to NT header
PIMAGE_NT_HEADERS ntheaders=(PIMAGE_NT_HEADERS)(PCHAR(virtualpointer) + PIMAGE_DOS_HEADER(virtualpointer)-> e_lfanew);
PIMAGE_SECTION_HEADER pSech=IMAGE_FIRST_SECTION(ntheaders);//Pointer to first section header
PIMAGE_IMPORT_DESCRIPTOR pImportDescriptor; //Pointer to import descriptor
__try
{
if(ntheaders->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_IMPORT].Size != 0)/*if size of the table is 0 - Import Table does not exist */
{
pImportDescriptor = (PIMAGE_IMPORT_DESCRIPTOR)((DWORD_PTR)virtualpointer +\
Rva2Offset(ntheaders->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_IMPORT].VirtualAddress,pSech,ntheaders));
LPSTR libname[256];
size_t i=0;
// Walk until you reached an empty IMAGE_IMPORT_DESCRIPTOR
while(pImportDescriptor->Name != NULL)
{
printf("Library Name :");
//Get the name of each DLL
libname[i]=(PCHAR)((DWORD_PTR)virtualpointer + Rva2Offset(pImportDescriptor->Name,ntheaders));
printf("%s\n",libname[i]);
pImportDescriptor++; //advance to next IMAGE_IMPORT_DESCRIPTOR
i++;
}
}
else
{
printf("No Import Table!\n");
return 1;
}
}
__except(EXCEPTION_EXECUTE_HANDLER)
{
if(EXCEPTION_ACCESS_VIOLATION == GetExceptionCode())
{
printf("Exception: EXCEPTION_ACCESS_VIOLATION\n");
return 1;
}
}
if(virtualpointer)
VirtualFree(virtualpointer,MEM_DECOMMIT);
return 0;
}
/*Convert Virtual Address to File Offset */
DWORD Rva2Offset(DWORD rva,PIMAGE_NT_HEADERS pnt)
{
size_t i = 0;
PIMAGE_SECTION_HEADER pSeh;
if(rva == 0)
{
return (rva);
}
pSeh = psh;
for(i = 0; i < pnt->FileHeader.NumberOfSections; i++)
{
if(rva >= pSeh->VirtualAddress && rva < pSeh->VirtualAddress +
pSeh->Misc.VirtualSize)
{
break;
}
pSeh++;
}
return (rva - pSeh->VirtualAddress + pSeh->PointerToRawData);
}
