Starx

Your question is very badly asked. So I will not dig into the logic of it.^Sorry Here is a very simple example of how you can create a Custom Validation Class.

The most important thing you need to remember is two methods.

1. isValid(): Returns either true or false through a logic
2. getMessages(): Returns errors messages in case of invalid.

Here is a basic example of comparing whether a user is admin or not.

class CustomValidate_UserAdmin extends Zend_Validate_Abstract
{
    $admin = "username"; //I am using a static value this time

    protected $_messageTemplates = array(
        self::FLOAT => "'%value%' is not an admin"
    );

    public function isValid($value)
    {
        $this->_setValue($value);

        if($this -> admin == $value) {     
             return true;
        }
    }
}

Now use it

$element->addValidator(new CustomValidate_UserAdmin('username'));

This is a very simple example to understand. You can replace it with your logic with a lot of ease I think.

Updates

Add validation like this…

$element->addValidator(new CustomValidate_Hash('file/location', $hashvaluettocompare));

Now in your validation class

function isValid($location, $value) {
   if(hash_file("md5", $location)==$value) return true;
}