Simple Random Pass Generator

function gen_pass()
{
	// load up our valid character string
	$chars	=	'01234567890';
	$chars	.=	'abcdefghijklmnopqrstuvwxyz';
	$chars	.=	'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
	$chars	.=	'~!@#$%^&*()_+{}[]|/?<>,.';
 
	// set password legnth between 8 and 14 characters long
	$len	= rand(8, 14);
 
	// initialize password & counter
	$pass	= '';
	$i		= 0;
 
	while ($i < $len)
	{
		// get a new character
		$new_char	= substr($chars, rand(0, strlen($chars) -1), 1);
 
		// ensure all characters are different
		if(! strstr($pass, $new_char))
		{
			$pass	.= $new_char;
			$i++;
		}
	}
 
	return $pass;
}