Código: Seleccionar todo

#include <stdio.h>
#include <stdlib.h>
#include <windows.h>
#include <string.h>

void inyectar(char * rutadll);

int main()
{
   	inyectar("c:\\windows\\system32\\fary.dll");
    return 0;
}

void inyectar(char * rutadll)
{
    DWORD id;
    DWORD mangoproc;
    HANDLE idproc;
    LPVOID espacio;
    LPVOID carga;
    
    printf("Inyeccion Dll by Drinky94\n");
    
    ShellExecute(0,0,"c:\\windows\\system32\\calc.exe",0,0,0);
    Sleep(2000); //  Esperamos que se ejecute la calculadora...
    id = FindWindow(NULL,"Calculadora");
    GetWindowThreadProcessId(id,&mangoproc);
    
    idproc = OpenProcess(PROCESS_ALL_ACCESS,0,mangoproc);
    
    carga = (LPVOID)GetProcAddress(GetModuleHandle("kernel32.dll"), "LoadLibraryA");
    espacio = (LPVOID)VirtualAllocEx(idproc,0,strlen(rutadll),MEM_COMMIT, PAGE_READWRITE);
    WriteProcessMemory(idproc,(LPVOID)espacio,rutadll,strlen(rutadll),0);
    CreateRemoteThread(idproc, 0, 0,(LPTHREAD_START_ROUTINE)carga,(LPVOID)espacio, 0, 0);
    
    CloseHandle(idproc);
    CloseHandle(espacio);
    
    system("PAUSE");      
}

Código: Seleccionar todo

format PE GUI 4.0 DLL
entry DllEntryPoint

include 'c:\include\win32ax.inc'

section '.code' code readable executable

proc DllEntryPoint hinstDLL,fdwReason,lpvReserved
        cmp [fdwReason],1
        JE mensage
        mensage:
        invoke MessageBox,0,mensajito,titulo,MB_OK
        ret
endp

; VOID ShowErrorMessage(HWND hWnd,DWORD dwError);

proc ShowErrorMessage hWnd,dwError
  local lpBuffer:DWORD
        lea     eax,[lpBuffer]
        invoke  FormatMessage,FORMAT_MESSAGE_ALLOCATE_BUFFER+FORMAT_MESSAGE_FROM_SYSTEM,0,[dwError],LANG_NEUTRAL,eax,0,0
        invoke  MessageBox,[hWnd],[lpBuffer],NULL,MB_ICONERROR+MB_OK
        invoke  LocalFree,[lpBuffer]
        ret
endp

; VOID ShowLastError(HWND hWnd);

proc ShowLastError hWnd
        invoke  GetLastError
        stdcall ShowErrorMessage,[hWnd],eax
        ret
endp
section '.data' data readable writeable
        mensajito db 'Dll Inyectada con exito',0
        titulo db ' Exito!!',0


section '.idata' import data readable writeable

  library kernel,'KERNEL32.DLL',\
          user,'USER32.DLL'

  import kernel,\
         GetLastError,'GetLastError',\
         SetLastError,'SetLastError',\
         FormatMessage,'FormatMessageA',\
         LocalFree,'LocalFree'

  import user,\
         MessageBox,'MessageBoxA'

section '.edata' export data readable

  export 'ERRORMSG.DLL',\
         ShowErrorMessage,'ShowErrorMessage',\
         ShowLastError,'ShowLastError'

section '.reloc' fixups data discardable