WBEM Class Wrapper for Local and Remote Process Creation

Windows 2000 introduces many new great features for us system programmers. Perhaps the best of these features is Microsoft's implementation of WBEM. WBEM is an industry wide initiative to make system management a more cross platform endevour. WBEM is incorporated deeply into Windows 2000, and is the facility by which all local and remote system information is gathered.

WBEM is implemented on the Windows 2000 platform as a system service. This service acts as a object request broker for almost any object in Windows (i.e. Process, Eventlog, Perfmon counters, Drivers, and so on) and can be used to create, query, or modify any of these objects via well documented COM calls.

Below I have implemented a class the will allow the creation of any specified process on a remote or local machine. I have included a test project implemented via a simple MFC dialog. Althought simplistic, the source should give you an idea of what can be accomplished with this new technology.

Make sure that you have included wbemuuid.lib in your linker settings. (This comes with platform SDK)

#include "wbemcli.h"
#include "comdef.h"

class CProcess
{

private:
 IWbemLocator     *pLocator;
 IWbemServices    *pService;
 IWbemClassObject *pInParameters;
 IWbemClassObject *pMethodObject;
 STDMETHODIMP     ConnectToWbem(_bstr_t bstrMachine, 
                                _bstr_t bstrUserID, 
                                _bstr_t bstrPassword);

public:
 CProcess();
 ~CProcess();
 STDMETHODIMP CreateNewProcess(_bstr_t bstrMachine, 
                               _bstr_t bstrUserID, 
                               _bstr_t bstrPassword, 
                               _variant_t vCommandLine);

};

CProcess::CProcess()
{
 CoInitialize(NULL);
}

CProcess::~CProcess()
{
 pInParameters->Release();
 pMethodObject->Release();
 pLocator->Release();
 pService->Release();
 CoUninitialize();
}

STDMETHODIMP CProcess::CreateNewProcess(_bstr_t bstrMachine, 
                                        _bstr_t, 
                                        bstrUserID, 
                                        _bstr_t bstrPassword, 
                                        _variant_t vCommandLine)
{
 HRESULT          hRes = 0;
 IWbemClassObject *pProcess = NULL;
 IWbemClassObject *pOutInst = NULL;

 if(FAILED(ConnectToWbem(bstrMachine, bstrUserID, bstrPassword)))
 {
  return E_FAIL;
 }

 hRes = pService->GetObject(_bstr_t(L"Win32_Process"), 
                            0, 
                            NULL, 
                            &pProcess, 
                            NULL);
 if(FAILED(hRes))
 {
  return E_FAIL; // Program has failed
 }

 hRes = pProcess->GetMethod(_bstr_t("Create"), 
                            0, 
                            &pInParameters, 
                            NULL);
 if(FAILED(hRes))
 {
  return E_FAIL;
 }

 hRes = pInParameters->SpawnInstance(0, &pMethodObject);
 if(FAILED(hRes))
 {
  return E_FAIL;
 }

 hRes = pMethodObject->Put(_bstr_t(L"CommandLine"), 
                           0, 
                           &vCommandLine, 
                           NULL);
 if(FAILED(hRes))
 {
  return E_FAIL;
 }

 hRes = pService->ExecMethod(_bstr_t(L"Win32_Process"),
                             _bstr_t(L"Create"), 
                              0, 
                              NULL, 
                              pMethodObject, 
                              &pOutInst, 
                              NULL);
 if(FAILED(hRes))
 {
  return E_FAIL;
 }

 pProcess->Release();
 pOutInst->Release();
 return S_OK;
}

STDMETHODIMP CProcess::ConnectToWbem(_bstr_t bstrMachine, 
                                     _bstr_t, 
                                     bstrUserID, 
                                     _bstr_t bstrPassword)
{
 HRESULT		hRes = 0;
 _bstr_t		szConnectionPath;

 hRes = CoCreateInstance(CLSID_WbemLocator, 
                         0, 
                         CLSCTX_INPROC_SERVER, 
                         IID_IWbemLocator, 
                         (LPVOID *) &pLocator);

 if (FAILED(hRes))
 {
  return E_FAIL; // Program has failed.
 }

 if(SysStringLen(bstrMachine) == 0)
 {
  //connect to local machine
  szConnectionPath += "root\\cimv2"; 
 }
 else
 {
  //set up connection string for remote machine
  szConnectionPath += "\\\\";
  szConnectionPath += bstrMachine;
  szConnectionPath += "\\root\\cimv2";
 }

 //if no UserName and PassWord supplied use NTLM to 
 //grab users access token
 if((SysStringLen(bstrUserID) == 0) 
 && (SysStringLen(bstrPassword) == 0))
 {
  hRes = pLocator->ConnectServer(szConnectionPath, 
                                 NULL, 
                                 NULL, 
                                 0, 
                                 NULL,	
                                 0, 
  0, &pService);
  if FAILED(hRes)
  {
   return E_FAIL; // Program has failed.
  }
 }
 else
 {
  // Connect to the Root\Default namespace with the current user.
  hRes = pLocator->ConnectServer(szConnectionPath, 
                                 bstrUserID, 
                                 bstrPassword, 
                                 0, 
                                 NULL, 
                                 0, 
                                 0, 
                                 &pService);
  if FAILED(hRes)
  {
   return E_FAIL;	   // Program has failed.
  }
 }

 // Set the proxy so that impersonation of the client occurs.
 hRes = CoSetProxyBlanket(pService, 
                          RPC_C_AUTHN_WINNT, 
                          RPC_C_AUTHZ_NONE, 
                          NULL, 
                          RPC_C_AUTHN_LEVEL_CALL, 
                          RPC_C_IMP_LEVEL_IMPERSONATE, 
                          NULL, 
                          EOAC_NONE);
 if(FAILED(hRes))
 {
  //user impersonation has failed!
  return E_FAIL;	   // Program has failed.
 }

 return S_OK;
}

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