ohctech_p8/includes/auth/auth.php

<?php 
$host_name="localhost";
$database_name="volvo";
$database_user="root";
$database_password="";


$conn = mysqli_connect($host_name,$database_user,$database_password,$database_name,3306);

$username=$_SESSION['username'];
$password=$_SESSION['userpassword'];
//session_cache_expire(60);
if(!validate($username, $password,$conn)){
	@header("Location: index.php?msg=Session Expired Please Login Again");
}
function validate($username, $password,$conn)
{
	if($username=="" ||  $password=="" )
	{
		return false;
	}
	$sql="select * from tbl_users where user_name='".$username."' AND user_password='".$password."'";
	$result=mysqli_query($conn, $sql);
	if(mysqli_num_rows($result) > 0)
	{
		return true;
	}
	else
	{
		return false;
	}
}