要分析PE文件我们首先要对PE结构有一个大致的了解,大体上PE结构可以看成是一个平面空间里面包含有如下内容
相应的MSDOS头结构定义如下,Windows加载器在加载的过程中会判断dos头是否合法
typedef struct _IMAGE_DOS_HEADER { // DOS .EXE header
WORD e_magic; // Magic number
WORD e_cblp; // Bytes on last page of file
WORD e_cp; // Pages in file
WORD e_crlc; // Relocations
WORD e_cparhdr; // Size of header in paragraphs
WORD e_minalloc; // Minimum extra paragraphs needed
WORD e_maxalloc; // Maximum extra paragraphs needed
WORD e_ss; // Initial (relative) SS value
WORD e_sp; // Initial SP value
WORD e_csum; // Checksum
WORD e_ip; // Initial IP value
WORD e_cs; // Initial (relative) CS value
WORD e_lfarlc; // File address of relocation table
WORD e_ovno; // Overlay number
WORD e_res[4]; // Reserved words
WORD e_oemid; // OEM identifier (for e_oeminfo)
WORD e_oeminfo; // OEM information; e_oemid specific
WORD e_res2[10]; // Reserved words
LONG e_lfanew; // File address of new exe header
} IMAGE_DOS_HEADER, *PIMAGE_DOS_HEADER;
通过以上结构我们可以看到e_lfanew(60=0x3c个字节偏移)字段代表exe头在文件中的位置(00F8)
所以可以断定00F8位置指向的内容为PE头结构定义如下
typedef struct _IMAGE_NT_HEADERS {
DWORD Signature; //PE头签名PE\0\0
IMAGE_FILE_HEADER FileHeader; //PE文件头
IMAGE_OPTIONAL_HEADER32 OptionalHeader; //PE扩展头
} IMAGE_NT_HEADERS32, *PIMAGE_NT_HEADERS32;
0xF9=50 45 00 00=PE\0\0->Signature签字段
000000fch=镜像头结构开发位置占20个字节
typedef struct _IMAGE_FILE_HEADER {
WORD Machine; //014C-IMAGE_FILE_MACHINE_I386
WORD NumberOfSections; //PE节数量-0007个节
DWORD TimeDateStamp; //时间戳E72B4FA9
DWORD PointerToSymbolTable; //指向符号表0000
DWORD NumberOfSymbols; //符号表数量0000
WORD SizeOfOptionalHeader; //扩展PE头大小00E0
WORD Characteristics; //文件属性0102-IMAGE_FILE_32BIT_MACHINE|IMAGE_FILE_EXECUTABLE_IMAGE
} IMAGE_FILE_HEADER, *PIMAGE_FILE_HEADER;
00000110h=扩展文件头起始位置占224个字节(E0)
typedef struct _IMAGE_OPTIONAL_HEADER {
//
// Standard fields.
//
WORD Magic; //010B-IMAGE_NT_OPTIONAL_HDR32_MAGIC
BYTE MajorLinkerVersion; //0A-连接器主版本号
BYTE MinorLinkerVersion; //00-连接器小版本号
DWORD SizeOfCode; //0000008A(138)-代码节大小
DWORD SizeOfInitializedData; //0000004C(76)-已初始化数据大小
DWORD SizeOfUninitializedData; //00000000(0)-为初始化数据大小
DWORD AddressOfEntryPoint; //000110AA程序入口地址
DWORD BaseOfCode; //00001000程序段基地址
DWORD BaseOfData; //00001000数据段基地址
//
// NT additional fields.
//
DWORD ImageBase; //镜像加载基地址00400000
DWORD SectionAlignment; //节对其0001000(4096)
DWORD FileAlignment; //文件对齐0000200(512)
WORD MajorOperatingSystemVersion; //操作系统主版本号0005
WORD MinorOperatingSystemVersion; //操作系统小版本号0001
WORD MajorImageVersion; //镜像主版本号0000
WORD MinorImageVersion; //镜像小版本号0000
WORD MajorSubsystemVersion; //子系统主版本号0005
WORD MinorSubsystemVersion; //子系统小版本号0001
DWORD Win32VersionValue; //0
DWORD SizeOfImage; //镜像大小00022000
DWORD SizeOfHeaders; //头大小0400
DWORD CheckSum; //0
WORD Subsystem; //03-IMAGE_SUBSYSTEM_WINDOWS_CUI
WORD DllCharacteristics; //8140IMAGE_DLLCHARACTERISTICS_TERMINAL_SERVER_AWARE
DWORD SizeOfStackReserve; //栈初始化大小010000
DWORD SizeOfStackCommit; //栈提交大小01000
DWORD SizeOfHeapReserve; //堆初始化大小010000
DWORD SizeOfHeapCommit; //堆提交大小01000
DWORD LoaderFlags; //0
DWORD NumberOfRvaAndSizes; //10(16)
IMAGE_DATA_DIRECTORY DataDirectory[IMAGE_NUMBEROF_DIRECTORY_ENTRIES];//数据目录表
} IMAGE_OPTIONAL_HEADER32, *PIMAGE_OPTIONAL_HEADER32;
到这里我们基本上已经将PE文件头信息给分析完成了.
下一篇我们来了解一下《导入表和函数地址导入表》