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从内存中加载DLL
yoours2011-07-08 16:57:57
简介一边听听音乐，一边写写文章。
#pragma once
typedef BOOL (__stdcall *ProcDllMain)(HINSTANCE, DWORD, LPVOID);
class CMemLoadDll
{
public:
CMemLoadDll();
virtual ~CMemLoadDll();
BOOL MemLoadLibrary( void* lpFileData , int DataLength);// Dll file data buffer
FARPROC MemGetProcAddress(LPCSTR lpProcName);
private:
BOOL isLoadOk;
BOOL CheckDataValide(void* lpFileData, int DataLength);
int CalcTotalImageSize();
void CopyDllDatas(void* pDest, void* pSrc);
BOOL FillRavAddress(void* pBase);
void DoRelocation(void* pNewBase);
int GetAlignedSize(int origin, int Alignment);
private:
ProcDllMain pDllMain;
private:
DWORD pImageBase;
PIMAGE_DOS_HEADER pDosHeader;
PIMAGE_NT_HEADERS pNTHeader;
PIMAGE_SECTION_HEADER pSectionHeader;
};
#include "stdafx.h"
#include "MemLoadDll.h"
CMemLoadDll::CMemLoadDll()
{
isLoadOk = FALSE;
pImageBase = NULL;
pDllMain = NULL;
}
CMemLoadDll::~CMemLoadDll()
{
if(isLoadOk)
{
ASSERT(pImageBase != NULL);
ASSERT(pDllMain != NULL);
//脱钩，准备卸载dll
pDllMain((HINSTANCE)pImageBase, DLL_PROCESS_DETACH, 0);
VirtualFree((LPVOID)pImageBase, 0, MEM_RELEASE);
}
}
//MemLoadLibrary函数从内存缓冲区数据中加载一个dll到当前进程的地址空间，缺省位置0×10000000
//返回值： 成功返回TRUE , 失败返回FALSE
//lpFileData: 存放dll文件数据的缓冲区
//DataLength: 缓冲区中数据的总长度
BOOL CMemLoadDll::MemLoadLibrary(void* lpFileData, int DataLength)
{
if(pImageBase != NULL)
{
return FALSE;//已经加载一个dll，还没有释放，不能加载新的dll
}
//检查数据有效性，并初始化
if(!CheckDataValide(lpFileData, DataLength))
return FALSE;
//计算所需的加载空间
int ImageSize = CalcTotalImageSize();
if(ImageSize == 0)
return FALSE;
// 分配虚拟内存
//void *pMemoryAddress = VirtualAlloc((LPVOID)0x10000000, ImageSize, MEM_COMMIT|MEM_RESERVE, PAGE_EXECUTE_READWRITE);
//修改, 不指定dll基址申请内存
void *pMemoryAddress = VirtualAlloc((LPVOID)NULL, ImageSize, MEM_COMMIT|MEM_RESERVE, PAGE_EXECUTE_READWRITE);
if(pMemoryAddress == NULL)
{
return FALSE;
}else {
CopyDllDatas(pMemoryAddress, lpFileData);//复制dll数据，并对齐每个段
//重定位信息
if(pNTHeader->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_BASERELOC].VirtualAddress >0 && pNTHeader->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_BASERELOC].Size>0)
{
DoRelocation(pMemoryAddress);
}
//填充引入地址表
if(!FillRavAddress(pMemoryAddress))//修正引入地址表失败
{
VirtualFree(pMemoryAddress, 0, MEM_RELEASE);
return FALSE;
}
//修改页属性。应该根据每个页的属性单独设置其对应内存页的属性。这里简化一下。
//统一设置成一个属性PAGE_EXECUTE_READWRITE
unsigned long old;
VirtualProtect(pMemoryAddress, ImageSize, PAGE_EXECUTE_READWRITE, &old);
}
//修正基地址
pNTHeader->OptionalHeader.ImageBase = (DWORD)pMemoryAddress;
//接下来要调用一下dll的入口函数，做初始化工作。
pDllMain = (ProcDllMain)(pNTHeader->OptionalHeader.AddressOfEntryPoint +(DWORD)pMemoryAddress);
BOOL InitResult = pDllMain((HINSTANCE)pMemoryAddress, DLL_PROCESS_ATTACH, 0);
if(!InitResult)//初始化失败
{
pDllMain((HINSTANCE)pMemoryAddress, DLL_PROCESS_DETACH, 0);
VirtualFree(pMemoryAddress, 0, MEM_RELEASE);
pDllMain = NULL;
return FALSE;
}
isLoadOk = TRUE;
pImageBase = (DWORD)pMemoryAddress;
return TRUE;
}
//MemGetProcAddress函数从dll中获取指定函数的地址
//返回值： 成功返回函数地址 , 失败返回NULL
//lpProcName: 要查找函数的名字或者序号
FARPROC CMemLoadDll::MemGetProcAddress(LPCSTR lpProcName)
{
if(pNTHeader->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_EXPORT].VirtualAddress == 0 || pNTHeader->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_EXPORT].Size == 0)
return NULL;
if(!isLoadOk)
return NULL;
DWORD OffsetStart = pNTHeader->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_EXPORT].VirtualAddress;
DWORD Size = pNTHeader->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_EXPORT].Size;
PIMAGE_EXPORT_DIRECTORY pExport = (PIMAGE_EXPORT_DIRECTORY)((DWORD)pImageBase + pNTHeader->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_EXPORT].VirtualAddress);
int iBase = pExport->Base;
int iNumberOfFunctions = pExport->NumberOfFunctions;
int iNumberOfNames = pExport->NumberOfNames;//<= iNumberOfFunctions
LPDWORD pAddressOfFunctions = (LPDWORD)(pExport->AddressOfFunctions + pImageBase);
LPWORD pAddressOfOrdinals = (LPWORD)(pExport->AddressOfNameOrdinals + pImageBase);
LPDWORD pAddressOfNames = (LPDWORD)(pExport->AddressOfNames + pImageBase);
int iOrdinal = -1;
if(((DWORD)lpProcName & 0xFFFF0000)== 0)//IT IS A orDINAL!
{
iOrdinal = (DWORD)lpProcName & 0x0000FFFF - iBase;
}else{
//use name
int iFound = -1;
for(int i=0;i<iNumberOfNames;i++)
{
char* pName= (char*)(pAddressOfNames[i] + pImageBase);
TRACE("Function - %s\r\n", pName);
if(strcmp(pName, lpProcName)== 0)
{
iFound = i;
break;
}
}
if(iFound >= 0)
{
iOrdinal = (int)(pAddressOfOrdinals[iFound]);
}
}
if(iOrdinal < 0 || iOrdinal >= iNumberOfFunctions)
{
return NULL;
}else{
DWORD pFunctionOffset = pAddressOfFunctions[iOrdinal];
if(pFunctionOffset > OffsetStart && pFunctionOffset < (OffsetStart+Size))//maybe Export Forwarding
return NULL;
else
return (FARPROC)(pFunctionOffset + pImageBase);
}
}
// 重定向PE用到的地址
void CMemLoadDll::DoRelocation(void *NewBase)
{
/* 重定位表的结构：
// DWORD sectionAddress, DWORD size (包括本节需要重定位的数据)
// 例如 1000节需要修正5个重定位数据的话，重定位表的数据是
// 00 10 00 00 14 00 00 00 xxxx xxxx xxxx xxxx xxxx 0000
// ———– ———– —-
// 给出节的偏移 总尺寸=8+6*2 需要修正的地址 用于对齐4字节
// 重定位表是若干个相连，如果address 和 size都是0 表示结束
// 需要修正的地址是12位的，高4位是形态字，intel cpu下是3
*/
//假设NewBase是0×600000, 而文件中设置的缺省ImageBase是0×400000, 则修正偏移量就是0×200000
DWORD Delta = (DWORD)NewBase - pNTHeader->OptionalHeader.ImageBase;
//注意重定位表的位置可能和硬盘文件中的偏移地址不同，应该使用加载后的地址
PIMAGE_BASE_RELOCATION pLoc = (PIMAGE_BASE_RELOCATION)((unsigned long)NewBase + pNTHeader->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_BASERELOC].VirtualAddress);
while((pLoc->VirtualAddress + pLoc->SizeOfBlock)!= 0)//开始扫描重定位表
{
WORD *pLocData = (WORD *)((int)pLoc + sizeof(IMAGE_BASE_RELOCATION));
//计算本节需要修正的重定位项（地址）的数目
int NumberOfReloc = (pLoc->SizeOfBlock - sizeof(IMAGE_BASE_RELOCATION))/sizeof(WORD);
for(int i=0 ;i < NumberOfReloc;i++)
{
if((DWORD)(pLocData[i] & 0xF000)== 0x00003000)//这是一个需要修正的地址
{
// 举例：
// pLoc->VirtualAddress = 0×1000;
// pLocData[i] = 0×313E;表示本节偏移地址0×13E处需要修正
// 因此 pAddress = 基地址 + 0×113E
// 里面的内容是 A1 (0c d4 02 10)汇编代码是： mov eax , [1002d40c]
// 需要修正1002d40c这个地址
DWORD * pAddress = (DWORD *)((unsigned long)NewBase + pLoc->VirtualAddress + (pLocData[i] & 0x0FFF));
*pAddress += Delta;
}
}
//转移到下一个节进行处理
pLoc = (PIMAGE_BASE_RELOCATION)((DWORD)pLoc + pLoc->SizeOfBlock);
}
}
//填充引入地址表
BOOL CMemLoadDll::FillRavAddress(void *pImageBase)
{
// 引入表实际上是一个 IMAGE_IMPORT_DESCRIPTOR 结构数组，全部是0表示结束
// 数组定义如下：
//
// DWORD originalFirstThunk;// 0表示结束，否则指向未绑定的IAT结构数组
// DWORD TimeDateStamp;
// DWORD ForwarderChain;// -1 if no forwarders
// DWORD Name;// 给出dll的名字
// DWORD FirstThunk;// 指向IAT结构数组的地址(绑定后，这些IAT里面就是实际的函数地址)
unsigned long Offset = pNTHeader->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_IMPORT].VirtualAddress ;
if(Offset == 0)
return TRUE;//No Import Table
PIMAGE_IMPORT_DESCRIPTOR pID = (PIMAGE_IMPORT_DESCRIPTOR)((unsigned long)pImageBase + Offset);
while(pID->Characteristics != 0)
{
PIMAGE_THUNK_DATA pRealIAT = (PIMAGE_THUNK_DATA)((unsigned long)pImageBase + pID->FirstThunk);
PIMAGE_THUNK_DATA pOriginalIAT = (PIMAGE_THUNK_DATA)((unsigned long)pImageBase + pID->OriginalFirstThunk);
//获取dll的名字
char buf[256];//dll name;
//修改, 需要buf清零, 否则dll名称不对
memset(buf, 0, sizeof(buf));
BYTE* pName = (BYTE*)((unsigned long)pImageBase + pID->Name);
for(int i=0;i<256;i++)
{
if(pName[i] == 0)
break;
buf[i] = pName[i];
}
HMODULE hDll = GetModuleHandle(buf);
if(hDll == NULL)
{
hDll = LoadLibrary (buf);//有可能依赖的dll还没有加载, 如果没有加载加载后再判断是否加载成功
if (hDll == NULL)
return FALSE;//NOT FOUND DLL
}//获取DLL中每个导出函数的地址，填入IAT
//每个IAT结构是 ：
// union {PBYTE ForwarderString;
// PDWORD Function;
// DWORD ordinal;
// PIMAGE_IMPORT_BY_NAME AddressOfData;
// }u1;
// 长度是一个DWORD ，正好容纳一个地址。
for(int i=0;;i++)
{
if(pOriginalIAT[i].u1.Function == 0)
break;
FARPROC lpFunction = NULL;
if(pOriginalIAT[i].u1.Ordinal & IMAGE_ORDINAL_FLAG)//这里的值给出的是导出序号
{
lpFunction = GetProcAddress(hDll, (LPCSTR)(pOriginalIAT[i].u1.Ordinal & 0x0000FFFF));
}else{
//按照名字导入
//获取此IAT项所描述的函数名称
PIMAGE_IMPORT_BY_NAME pByName = (PIMAGE_IMPORT_BY_NAME)
((DWORD)pImageBase + (DWORD)(pOriginalIAT[i].u1.AddressOfData));
// if(pByName->Hint !=0)
// lpFunction = GetProcAddress(hDll, (LPCSTR)pByName->Hint);
// else
lpFunction = GetProcAddress(hDll, (char *)pByName->Name);
}
if(lpFunction != NULL)//找到了！
{
pRealIAT[i].u1.Function = (DWORD)lpFunction;
}else{
return FALSE;
}
}
//move to next
pID = (PIMAGE_IMPORT_DESCRIPTOR)((DWORD)pID + sizeof(IMAGE_IMPORT_DESCRIPTOR));
}
return TRUE;
}
//CheckDataValide函数用于检查缓冲区中的数据是否有效的dll文件
//返回值： 是一个可执行的dll则返回TRUE，否则返回FALSE。
//lpFileData: 存放dll数据的内存缓冲区
//DataLength: dll文件的长度
BOOL CMemLoadDll::CheckDataValide(void* lpFileData, int DataLength)
{
//检查长度
if(DataLength < sizeof(IMAGE_DOS_HEADER))
return FALSE;
pDosHeader = (PIMAGE_DOS_HEADER)lpFileData;// DOS头
//检查dos头的标记
if(pDosHeader->e_magic != IMAGE_DOS_SIGNATURE)
return FALSE;//0*5A4D : MZ
//检查长度
if((DWORD)DataLength < (pDosHeader->e_lfanew + sizeof(IMAGE_NT_HEADERS)))
return FALSE;
//取得pe头
pNTHeader = (PIMAGE_NT_HEADERS)((unsigned long)lpFileData + pDosHeader->e_lfanew);// PE头
//检查pe头的合法性
if(pNTHeader->Signature != IMAGE_NT_SIGNATURE)
return FALSE;//0*00004550 : PE00
if((pNTHeader->FileHeader.Characteristics & IMAGE_FILE_DLL)== 0)//0*2000 : File is a DLL
return FALSE;
if((pNTHeader->FileHeader.Characteristics & IMAGE_FILE_EXECUTABLE_IMAGE)== 0)//0*0002 : 指出文件可以运行
return FALSE;
if(pNTHeader->FileHeader.SizeOfOptionalHeader != sizeof(IMAGE_OPTIONAL_HEADER))
return FALSE;
//取得节表（段表）
pSectionHeader = (PIMAGE_SECTION_HEADER)((int)pNTHeader + sizeof(IMAGE_NT_HEADERS));
//验证每个节表的空间
for(int i=0;i< pNTHeader->FileHeader.NumberOfSections;i++)
{
if((pSectionHeader[i].PointerToRawData + pSectionHeader[i].SizeOfRawData)> (DWORD)DataLength)
return FALSE;
}
return TRUE;
}
//计算对齐边界
int CMemLoadDll::GetAlignedSize(int Origin, int Alignment)
{
return (Origin + Alignment - 1)/ Alignment * Alignment;
}
//计算整个dll映像文件的尺寸
int CMemLoadDll::CalcTotalImageSize()
{
int Size;
if(pNTHeader == NULL)return 0;
int nAlign = pNTHeader->OptionalHeader.SectionAlignment;//段对齐字节数
// 计算所有头的尺寸。包括dos, coff, pe头 和 段表的大小
Size = GetAlignedSize(pNTHeader->OptionalHeader.SizeOfHeaders, nAlign);
// 计算所有节的大小
for(int i=0;i < pNTHeader->FileHeader.NumberOfSections;++i)
{
//得到该节的大小
int CodeSize = pSectionHeader[i].Misc.VirtualSize ;
int LoadSize = pSectionHeader[i].SizeOfRawData;
int MaxSize = (LoadSize > CodeSize)?(LoadSize):(CodeSize);
int SectionSize = GetAlignedSize(pSectionHeader[i].VirtualAddress + MaxSize, nAlign);
if(Size < SectionSize)
Size = SectionSize;//Use the Max;
}
return Size;
}
//CopyDllDatas函数将dll数据复制到指定内存区域，并对齐所有节
//pSrc: 存放dll数据的原始缓冲区
//pDest:目标内存地址
void CMemLoadDll::CopyDllDatas(void* pDest, void* pSrc)
{
// 计算需要复制的PE头+段表字节数
int HeaderSize = pNTHeader->OptionalHeader.SizeOfHeaders;
int SectionSize = pNTHeader->FileHeader.NumberOfSections * sizeof(IMAGE_SECTION_HEADER);
int MoveSize = HeaderSize + SectionSize;
//复制头和段信息
memmove(pDest, pSrc, MoveSize);
//复制每个节
for(int i=0;i < pNTHeader->FileHeader.NumberOfSections;++i)
{
if(pSectionHeader[i].VirtualAddress == 0 || pSectionHeader[i].SizeOfRawData == 0)
continue;
// 定位该节在内存中的位置
void *pSectionAddress = (void *)((unsigned long)pDest + pSectionHeader[i].VirtualAddress);
// 复制段数据到虚拟内存
memmove((void *)pSectionAddress, (void *)((DWORD)pSrc + pSectionHeader[i].PointerToRawData), pSectionHeader[i].SizeOfRawData);
}
//修正指针，指向新分配的内存
//新的dos头
pDosHeader = (PIMAGE_DOS_HEADER)pDest;
//新的pe头地址
pNTHeader = (PIMAGE_NT_HEADERS)((int)pDest + (pDosHeader->e_lfanew));
//新的节表地址
pSectionHeader = (PIMAGE_SECTION_HEADER)((int)pNTHeader + sizeof(IMAGE_NT_HEADERS));
}
调用方法：
void CMyTestDlg::OnBnClickedOk()
{
HANDLE hFile = CreateFile("E:\\MyDll.DLL", GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, 0, NULL);
if (hFile == INVALID_HANDLE_VALUE)
{
return;
}
LARGE_INTEGER val;
val.LowPart = GetFileSize(hFile, (DWORD*)&val.HighPart);
if(val.LowPart == 0xFFFFFFFF && GetLastError()!= NO_ERROR)
{
CloseHandle(hFile);
return;
}
byte* buf = new byte[val.LowPart];
DWORD nRead;
if(!ReadFile(hFile, buf, val.LowPart, &nRead, NULL))
{
CloseHandle(hFile);
return;
}
CloseHandle(hFile);
LPVOID pBuffer =(LPSTR)buf;
char* str = "?iMyDllGetVer@@YAMXZ";
char* FunName = new char[strlen(str) + 1];
memcpy(FunName, str, strlen(str));
FunName[strlen(str)] = '\0';
float version = 0;
//对pBuffer进行处理
CMemLoadDll* pMemLoadDll=new CMemLoadDll();
//加载dll到当前进程的地址空间
if(pMemLoadDll->MemLoadLibrary(pBuffer, val.LowPart))
{
MyDllGetVer FunMyDllGetVer = (MyDllGetVer)pMemLoadDll->MemGetProcAddress(FunName);
if(FunMyDllGetVer == NULL)
{
return;
}
version = (*FunMyDllGetVer)();
}
delete pMemLoadDll;
delete[] FunName;
FunName = NULL;
delete[] buf;
buf = NULL;
}
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