在PE中，新增节，添加代码

在PE中，新增节，添加代码

一、先判断节表后是否有空闲位置，添加节表信息，必须多出两个节表位置，最后以零结尾。

二、新增节后，需要修改以下信息

　　1、添加一个新节，可以复制一份，最好是拥有可执行属性的节，如.text。

　　2、在节表区，新增节的后面，填充一个节，用零填充。

　　3、修改标准PE头中节的数量。

　　4、修改SizeOfImage的大小。

　　5、在原有数据的后面，新增一个节的数据（内存对齐的整倍数）。

　　6、修正新增节表的属性。

三、新节各个属性修改说明

　　1、Name:名字随便修改，不能超过八个字节。

　　2、VirtualSize:申请的新节空间大小，比如1000

　　3、VirtualAddress:等于上一个节的VirtualAddress + SizeOfRawData

　　4、SizeOfRawData：设置可以和VirtualSize一样，比如1000

　　5、PointerToRawData：等于上一个节的PointerToRawData+ SizeOfRawData

　　6、PointerToRelocation：设置成零

　　7、PointerToLineNumbers：设置成零

　　8、NumberOfLineRelocations：设置成零

　　9、NumberOfLineNumbers：设置成零

　　10、Characteristics：块属性0x20000060 可以取上一个节表和本节表的属性值，进行异或 如x|y

标志(属性块) 常用特征值对照表：

[值:00000020h] [IMAGE_SCN_CNT_CODE // Section contains code.(包含可执行代码)]

[值:00000040h] [IMAGE_SCN_CNT_INITIALIZED_DATA // Section contains initialized data.(该块包含已初始化的数据)]

[值:00000080h] [IMAGE_SCN_CNT_UNINITIALIZED_DATA // Section contains uninitialized data.(该块包含未初始化的数据)]

[值:00000200h] [IMAGE_SCN_LNK_INFO // Section contains comments or some other type of information.]

[值:00000800h] [IMAGE_SCN_LNK_REMOVE // Section contents will not become part of image.]

[值:00001000h] [IMAGE_SCN_LNK_COMDAT // Section contents comdat.]

[值:00004000h] [IMAGE_SCN_NO_DEFER_SPEC_EXC // Reset speculative exceptions handling bits in the TLB entries for this section.]

[值:00008000h] [IMAGE_SCN_GPREL // Section content can be accessed relative to GP.]

[值:00500000h] [IMAGE_SCN_ALIGN_16BYTES // Default alignment if no others are specified.]

[值:01000000h] [IMAGE_SCN_LNK_NRELOC_OVFL // Section contains extended relocations.]

[值:02000000h] [IMAGE_SCN_MEM_DISCARDABLE // Section can be discarded.]

[值:04000000h] [IMAGE_SCN_MEM_NOT_CACHED // Section is not cachable.]

[值:08000000h] [IMAGE_SCN_MEM_NOT_PAGED // Section is not pageable.]

[值:10000000h] [IMAGE_SCN_MEM_SHARED // Section is shareable(该块为共享块).]

[值:20000000h] [IMAGE_SCN_MEM_EXECUTE // Section is executable.(该块可执行)]

[值:40000000h] [IMAGE_SCN_MEM_READ // Section is readable.(该块可读)]

[值:80000000h] [IMAGE_SCN_MEM_WRITE // Section is writeable.(该块可写)]

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// mem.cpp : 定义控制台应用程序的入口点。
//PE文件从文件加载到内存，再从内存读取，然后存盘到文件

#include "stdafx.h"
#include <windows.h>
#include <winnt.h>

//#define  PATH "C:\\Windows\\System32\\notepad.exe"
#define  PATH "C:\\Users\\Administrator\\Desktop\\ipmsg.exe"
#define  MsgADD 0x75cffde6
char Shellcode[] =
{
0x6A, 0x00, 0x6A, 0x00, 0x6A, 0x00, 0x6A, 0x00,
0xE8, 0x00, 0x00, 0x00, 0x00,
0xE9, 0x00, 0x00, 0x00, 0x00
};

int Filelength(FILE *fp);
int _tmain(int argc, _TCHAR* argv[])
{
FILE *Fp;
fopen_s(&Fp, PATH, "rb");
int FileSize = Filelength(Fp);//获取文件大小
char * FileBuffer = (char *)malloc(FileSize);//申请存放文件的内存空间
if (FileBuffer == NULL)
{
printf("申请iImageBuffer失败");
}
fread_s(FileBuffer, FileSize, 1, FileSize, Fp); //将文件复制到内存中
//定位一下内存中的数据 各个头表
//定位标准PE头
PIMAGE_FILE_HEADER MyFileHeader;
MyFileHeader = (PIMAGE_FILE_HEADER)(char *)(FileBuffer + *(int *)(FileBuffer + 0x3c) + 0x4);
//定位可选PE头
PIMAGE_OPTIONAL_HEADER  MyOptionalHeader;
MyOptionalHeader = (PIMAGE_OPTIONAL_HEADER)((char *)MyFileHeader + 0x14);
//定位节表
PIMAGE_SECTION_HEADER MySectionHeader;
MySectionHeader = (PIMAGE_SECTION_HEADER)((char *)MyOptionalHeader + MyFileHeader->SizeOfOptionalHeader);

//拉伸，也就是读到内存中的状态
char * ImageBuffer = (char *)malloc(MyOptionalHeader->SizeOfImage+0x1000);//给拉伸申请内存空间
ZeroMemory(ImageBuffer, MyOptionalHeader->SizeOfImage+0x1000);

if (ImageBuffer == NULL)
{
printf("申请iImageBuffer失败");
}
memcpy(ImageBuffer, FileBuffer, MyOptionalHeader->SizeOfHeaders);

for (int i = 0; i < MyFileHeader->NumberOfSections; i++)
{
memcpy(ImageBuffer + MySectionHeader->VirtualAddress, FileBuffer + MySectionHeader->PointerToRawData, MySectionHeader->SizeOfRawData);//
MySectionHeader++;
}
//新增节开始
PIMAGE_SECTION_HEADER AddSectionHeader;
AddSectionHeader = MySectionHeader;
MySectionHeader--;
//AddSectionHeader->Name = "cyp";
//AddSectionHeader->Name = { 0 };
AddSectionHeader->Name[0] = '.'; AddSectionHeader->Name[1] = 'c'; AddSectionHeader->Name[2] = 'y'; AddSectionHeader->Name[3] = 'p';
AddSectionHeader->Misc.VirtualSize = 0x1000;
AddSectionHeader->VirtualAddress = MySectionHeader->VirtualAddress + MySectionHeader->SizeOfRawData;
AddSectionHeader->SizeOfRawData = 0x1000;
AddSectionHeader->PointerToRawData = MySectionHeader->PointerToRawData + MySectionHeader->SizeOfRawData;
int x = (MySectionHeader - (MyFileHeader->NumberOfSections-1))->Characteristics;
AddSectionHeader->Characteristics = x;
MyFileHeader->NumberOfSections += 1;
MyOptionalHeader->SizeOfImage + 0x1000;
//新增节结束

//添加代码到PE中
MyFileHeader = (PIMAGE_FILE_HEADER)(char *)(ImageBuffer + *(int *)(ImageBuffer + 0x3c) + 0x4);
MyOptionalHeader = (PIMAGE_OPTIONAL_HEADER)((char *)MyFileHeader + 0x14);
MySectionHeader = (PIMAGE_SECTION_HEADER)((char *)MyOptionalHeader + MyFileHeader->SizeOfOptionalHeader);//重新指一下，前面动过了

//E8后面的硬编码地址 ＝真正要到的地址 - E8的下一行或E8本行 +0x5
char *CodeAdd = ImageBuffer + MySectionHeader->VirtualAddress + MySectionHeader->Misc.VirtualSize;//为要增加的代码确定位置
memcpy(CodeAdd, Shellcode, sizeof(Shellcode));//把硬编码复制到指定位置
int CallAdd = MsgADD - (MyOptionalHeader->ImageBase + ((int)(CodeAdd + 0xd) - (int)ImageBuffer));
*(int *)(CodeAdd + 0x9) = CallAdd;//定位CALL函数位置
int JmpAdd = MyOptionalHeader->ImageBase + MyOptionalHeader->AddressOfEntryPoint - (MyOptionalHeader->ImageBase + (CodeAdd + 0xd - ImageBuffer));//前面是真正要跳的地址  后面括号是下一条指令的地址
*(int *)(CodeAdd + 0xe) = JmpAdd;//定位JMP 跳回位置，也就是修改程序入口
MyOptionalHeader->AddressOfEntryPoint = CodeAdd - ImageBuffer;//重新定位程序入口处

//添加代码到PE结束

//压缩，为存盘做准备
char *NewBuffer = (char *)malloc(FileSize+0x1000);//给压缩申请内存空间
if (NewBuffer == NULL)
{
printf("申请iImageBuffer失败");
}
memcpy(NewBuffer, ImageBuffer, MyOptionalHeader->SizeOfHeaders);
MySectionHeader = (PIMAGE_SECTION_HEADER)((char *)MyOptionalHeader + MyFileHeader->SizeOfOptionalHeader);//重新指一下，前面动过了

for (int i = 0; i < MyFileHeader->NumberOfSections; i++)
{
memcpy(NewBuffer + MySectionHeader->PointerToRawData, ImageBuffer + MySectionHeader->VirtualAddress, MySectionHeader->SizeOfRawData);
MySectionHeader++;
}
FILE *nFp;
fopen_s(&nFp, "C:\\Users\\Administrator\\Desktop\\CYP.exe", "wb");
fwrite(NewBuffer, FileSize, 1, nFp);

//getchar();
fclose(nFp);
free(FileBuffer);
free(ImageBuffer);
free(NewBuffer);
return 0;
}

//获取文件大小

int Filelength(FILE *fp)
{
int num;
fseek(fp, 0, SEEK_END);
num = ftell(fp);
fseek(fp, 0, SEEK_SET);
return num;
}