Elevating During Runtime

// How to Elevate during runtime - POC by Michael Haephrati
// �2011 Michael Haephrati (haephrati@gmail.com )

#include "stdafx.h"

BOOL IsRunAsAdministrator()
{
    BOOL fIsRunAsAdmin = FALSE;
    DWORD dwError = ERROR_SUCCESS;
    PSID pAdministratorsGroup = NULL;

    // Allocate and initialize a SID of the administrators group.
    SID_IDENTIFIER_AUTHORITY NtAuthority = SECURITY_NT_AUTHORITY;
    if (!AllocateAndInitializeSid(
        &NtAuthority, 
        2, 
        SECURITY_BUILTIN_DOMAIN_RID, 
        DOMAIN_ALIAS_RID_ADMINS, 
        0, 0, 0, 0, 0, 0, 
        &pAdministratorsGroup))
    {
        dwError = GetLastError();
        goto Cleanup;
    }

    // Determine whether the SID of administrators group is enabled in 
    // the primary access token of the process.
    if (!CheckTokenMembership(NULL, pAdministratorsGroup, &fIsRunAsAdmin))
    {
        dwError = GetLastError();
        goto Cleanup;
    }

Cleanup:
    // Centralized cleanup for all allocated resources.
    if (pAdministratorsGroup)
    {
        FreeSid(pAdministratorsGroup);
        pAdministratorsGroup = NULL;
    }

    // Throw the error if something failed in the function.
    if (ERROR_SUCCESS != dwError)
    {
        throw dwError;
    }

    return fIsRunAsAdmin;
}

void ElevateNow()
{
	BOOL bAlreadyRunningAsAdministrator = FALSE;
	try
	{
		bAlreadyRunningAsAdministrator = IsRunAsAdministrator();
	}
	catch(...)
	{
		std::cout << "Failed to determine if application was running with admin rights" << std::endl;
		DWORD dwErrorCode = GetLastError();
		TCHAR szMessage[256];
		_stprintf_s(szMessage, ARRAYSIZE(szMessage), _T("Error code returned was 0x%08lx"),dwErrorCode);
		std::cout << szMessage << std::endl;
	}
	if(!bAlreadyRunningAsAdministrator)
	{
		wchar_t szPath[MAX_PATH];
		if (GetModuleFileName(NULL, szPath, ARRAYSIZE(szPath)))
		{
			// Launch itself as admin
			SHELLEXECUTEINFO sei = { sizeof(sei) };
			sei.lpVerb = L"runas";
			sei.lpFile = szPath;
			sei.hwnd = NULL;
			sei.nShow = SW_NORMAL;

			if (!ShellExecuteEx(&sei))
			{
				DWORD dwError = GetLastError();
				if (dwError == ERROR_CANCELLED)
				{
					// The user refused to allow privileges elevation.
					std::cout << "End user did not allow elevation" << std::endl;
				}
			}
			else
			{
				_exit(1);  // Quit itself
			}
		}
	}
}

int _tmain(int argc, _TCHAR* argv[])
{
	
	std::cout << "How to Elevate during runtime - POC by Michael Haephrati" << std::endl;
	
	std::cout << "Press Y <ENTER> to elevate, or any other key <ENTER> to quit" << std::endl;
	TCHAR ch = getchar();
	if(ch == 'Y' || ch == 'y')
	{
		if(IsRunAsAdministrator())
		{
			std::cout << "The applicaiton is already running with admin privileges" << std::endl;
		}
		else
		{
			ElevateNow();
		}

		std::cout << "(please send your comments to Michael Haephrati haephrati@gmail.com) Press any key to continue";
		std::cin.get();
		std::cin.get();
	}
	else
	{		
		std::cout << "(please send your comments to Michael Haephrati haephrati@gmail.com) Press any key to continue ...";
		std::cin.get();
		std::cin.get();
	}

	return 0;
}