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

void errorprint(char *szFormatString, ...)
{
	DWORD dwGLE = GetLastError();
	char szBuffer1[(MAX_PATH * 2) + 1], szBuffer2[(MAX_PATH * 2) + 1];
	va_list marker;

	_snprintf(szBuffer1, (MAX_PATH * 2), "ERROR: %s (GLE: %d/0x%X)\n", szFormatString, dwGLE, dwGLE);
	va_start(marker, szFormatString);
	_vsnprintf(szBuffer2, (MAX_PATH * 2), szBuffer1, marker);
	va_end(marker); // just to be thorough
	szBuffer2[(MAX_PATH * 2)] = 0;
	printf(szBuffer2);
}

BOOL SetPrivilege(
	HANDLE hToken,          // access token handle
	LPCTSTR lpszPrivilege,  // name of privilege to enable/disable
	BOOL bEnablePrivilege   // to enable or disable privilege
	) 
{
	TOKEN_PRIVILEGES tp;
	LUID luid;

	if ( !LookupPrivilegeValue( 
        	NULL,            // lookup privilege on local system
	        lpszPrivilege,   // privilege to lookup 
        	&luid ) ) {      // receives LUID of privilege
		printf("LookupPrivilegeValue error: %u\n", GetLastError() ); 
		return FALSE; 
	}
	
	tp.PrivilegeCount = 1;	
	tp.Privileges[0].Luid = luid;	
	if (bEnablePrivilege) tp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;
	else tp.Privileges[0].Attributes = 0;

	// Enable the privilege or disable all privileges.

	AdjustTokenPrivileges(
		hToken, 
		FALSE, 
		&tp, 
		sizeof(TOKEN_PRIVILEGES), 
		(PTOKEN_PRIVILEGES) NULL, 
		(PDWORD) NULL); 
 
	// Call GetLastError to determine whether the function succeeded.

	if (GetLastError() != ERROR_SUCCESS) { 
		printf("AdjustTokenPrivileges failed: %u\n", GetLastError() ); 
		return FALSE; 
	} 

	return TRUE;
}

BOOL ListPrivileges(HANDLE hToken)
{
	BOOL fSuccess;
	TOKEN_PRIVILEGES *pBuffer = NULL;
	DWORD dwBufSize = 0, dwSecondBufSize = 0;
	DWORD dwGLE;

	fSuccess = GetTokenInformation(
		hToken,
		TokenPrivileges,
		pBuffer,
		0,
		&dwBufSize);

	if (!fSuccess) {
		dwGLE = GetLastError();
		if (dwGLE != 122 || !dwBufSize) {
			errorprint("couldn't get current token privileges");
			return FALSE;
		}
	} else {
		errorprint("uhhh... something's wrong; we shouldn't be able to GTI with a null buffer");
		return FALSE;
	}
	
	// theoretically, we now have the needed buffer size in dwBufSize
	pBuffer = (TOKEN_PRIVILEGES *)malloc(dwBufSize);
	if (!pBuffer) {
		errorprint("couldn't allocate %d byte buffer", dwBufSize);
		return FALSE;
	}

	fSuccess = GetTokenInformation(
		hToken,
		TokenPrivileges,
		pBuffer,
		dwBufSize,
		&dwSecondBufSize);


	if (!fSuccess) {
		errorprint("GetTokenInformation (second call) failed (bufsize: %d)", dwBufSize);
		free(pBuffer);
		return FALSE;
	} else if (dwSecondBufSize != dwBufSize) {
		errorprint("GetTokenInformation returned wrong number of bytes read (was %d, should be %d)", dwSecondBufSize, dwBufSize);
		free(pBuffer);
		return FALSE;
	}

	// ok, now we (theoretically) have an array of TOKEN_PRIVILEGES structures in pvBuffer
	int nPrivCount = dwBufSize / sizeof(TOKEN_PRIVILEGES);
	for (int i = 0; i < nPrivCount; ++i) {
		char szBuffer[MAX_PATH + 1];
		LUID *pPrivLuid = &pBuffer->Privileges[i].Luid;
		DWORD dwPrivAttributes = pBuffer->Privileges[i].Attributes, cbName = MAX_PATH;

		fSuccess = LookupPrivilegeName(NULL, pPrivLuid, szBuffer, &cbName);
		if (!fSuccess) {
			errorprint("LookupPrivilegeName failed for privilege %d", i);
			free(pBuffer);
			return FALSE;
		}
		
		printf("%40s", szBuffer);
		szBuffer[0] = 0;
		if (dwPrivAttributes & SE_PRIVILEGE_ENABLED) {
			strcat(szBuffer, "enabled");
		}
		if (dwPrivAttributes & SE_PRIVILEGE_ENABLED_BY_DEFAULT) {
			if (szBuffer[0]) strcat(szBuffer, ", ");
			strcat(szBuffer, "enabled by default");
		}
		if (dwPrivAttributes & SE_PRIVILEGE_USED_FOR_ACCESS) {
			if (szBuffer[0]) strcat(szBuffer, ", ");
			strcat(szBuffer, "used for access");
		}
		if (szBuffer[0]) printf(" (%s)\n", szBuffer);
		else printf("\n");
	}
	
	free(pBuffer);
	return TRUE;	
}

void main(void)
{
	HANDLE hThisProcess = GetCurrentProcess();
	HANDLE hToken = INVALID_HANDLE_VALUE;
	BOOL fSuccess;
	DWORD dwGLE;

	fSuccess = OpenProcessToken(
		hThisProcess, 
		TOKEN_ALL_ACCESS, 
		&hToken
	);

	if (!fSuccess) {
		errorprint("couldn't open process token for current process");
		exit(1);
	}

	printf("Privileges before setting SeDebugPrivilege...\n");
	printf("---------------------------------------------\n");
	fSuccess = ListPrivileges(hToken);
	
	if (!fSuccess) {
		errorprint("ListPrivileges failed, exiting...");
		CloseHandle(hToken);
		exit(1);
	}
	
	fSuccess = SetPrivilege(hToken, "SeDebugPrivilege", TRUE);

	if (!fSuccess) {
		errorprint("SetPrivilege(\"SeDebugPrivilege\") failed, exiting...");
		CloseHandle(hToken);
		exit(1);
	}

	printf("\nPrivileges after setting SeDebugPrivilege... \n");
	printf("--------------------------------------------\n");
	fSuccess = ListPrivileges(hToken);
	
	if (!fSuccess) {
		errorprint("ListPrivileges failed, exiting...");
		CloseHandle(hToken);
		exit(1);
	}

	CloseHandle(hToken);
	exit(0);
}