magento custom gateaway payment redirect is 404

I made a custom payment gateaway for asurepay. It's like paypal standard payment for short. In place my order and it will redirect to a redirect page of my module, here is the problem. It gives me a 404 page.

Here is my file structure. (In case you need to study)

- app/
  - code/
    - local/
      - Asurepay/
        - Custompay/
          - Model/
            - Asure.php
          - Block/
            - Asure/
              -Redirect.php
            - Form.php
            - Info.php
          - etc/
            - config.xml
            - system.xml
  - design/
    - adminhtml/
      - ......
    - frontend/
      - default/
        - default/
          - template/
            - custompay/
              - asurepay/
                - redirect.phtml
         开发者_如何学运维     - form.phtml
  - etc/
    - modules/
      - Asurepay_Custompay.xml

Here is my Model/Asure redirect code:

public function getOrderPlaceRedirectUrl() {
   return Mage::getUrl('custompay/asurepay/redirect', array('_secure' => true));
}

Here is my config.xml as requested

<config>
    <modules>
        <Asurepay_Custompay>
            <version>0.1.0</version>
        </Asurepay_Custompay>
    </modules>
    <global>
        <blocks>
            <custompay>
                <class>Asurepay_Custompay_Block</class>
            </custompay>
        </blocks>
        <models>
            <custompay>
                <class>Asurepay_Custompay_Model</class>
            </custompay>
        </models>
        <resources>
            <custompay_setup>
                <setup>
                    <module>Asurepay_Custompay</module>
                </setup>
                <connection>
                    <use>core_setup</use>
                </connection>
            </custompay_setup>
            <custompay_write>
                <connection>
                    <use>core_write</use>
                </connection>
            </custompay_write>
            <custompay_read>
                <connection>
                    <use>core_read</use>
                </connection>
            </custompay_read>
        </resources>
    </global>
    <default>
        <payment>
            <custompay>
                <active>1</active>
                <model>custompay/asure</model>
                <order_status>pending</order_status>
                <title>AsurePay</title>
                <gateurl>https://www.paymentUrl.com/payment/</gateurl>
                <successurl>{{base_url}}</successurl>
                <redimsg>You will be redirected to the payment website when you place an order.</redimsg>
                <allowspecific>0</allowspecific>
            </custompay>
        </payment>
    </default>
</config>

Obviously the redirect url is:

www.mydomain.com/custompay/asurepay/redirect/

This url gives me a 404 page.

How can I tell magento to create a redirect page so it will not be 404 or how can i make the www.mydomain.com/custompay/asurepay/redirect/ page via controller.?

Ask me if you need more info. :) thanks a lot.

you need to define frontend router for your extension and probably also layout references , the issue is there that you don't have controller access defined for frontend

<frontend>
        <routers>
            <custompay>
                <use>standard</use>
                <args>
                    <module>Asurepay_Custompay</module>
                    <frontName>custompay</frontName>
                </args>
            </custompay>
        </routers>
</frontend>