Utilizing Username & Password Fields for another systems

[Mohajer]

Hello ,
How i can use vbulletin Username & Password Fields for my new program ?


For example in my script i use below code for identity users:
( Only Example )

PHP Code:

 
$user = $_POST['uname'];
$pass = md5($_POST['upass']);
$auth=mysql_query("SELECT passowrd FROM user WHERE username='$user' ") or die(mysql_error());
 
 if(mysql_num_rows($auth) == 1) 
{
 
...........
 
 
}else {
...........
 
} 


Now , how it possible i change my script for use vbulletin username/password Fields for identity my vbulletin users in non vbulletin scripts ?

Thank you.