How to allow Specific Web Categories on SonicOSX 7.0?

08/28/2020 1 4845

DESCRIPTION:

SonicWall has an implicit deny rule that blocks all traffic. To allow a specific web category or set of web categories, such as News, Search Engines etc we need to add a security rule that explicitly permits them. Security rules consist of three sections, match criterion, action, and additional actions. We need to match the Web categories to be allowed, allow access to them, and perform additional actions like displaying a block page for others that aren't allowed.

RESOLUTION:

To allow only only certain web categories through the firewall on SonicOSX 7.0, we need to do the following

1. Create a Decryption policy 
2. Create Security Policies

 NOTE: On SonicOSX 7.0, the HTTPS content filtering is no longer present. So, if HTTPS websites are to be allowed, we need Client DPI SSL and a corresponding decryption policy to inspect them.

Creating a Decryption Policy:

A decryption policy matches the traffic and the only two actions we can take are Decrypt and Bypass. With decryption, we get greater data visibility, which help us in performing better matches and applying the right security policy.

1. Make sure that Client DPI SSL is enabled globally based on the KB: How to create a Decryption Policy on SonicOSX 7.0?
2. Navigate to the Policy | Rules and Policies | Decryption Policy tab and click on Top at the bottom of the screen. If you have multiple policies, it is very important to choose the correct priority to make sure that the decryption policy gets applied to the necessary traffic.
   
   
   
   
3. From here, you can select the appropriate source/destination/service or you can leave it all on Any to decrypt all traffic. Make sure that the action is set to Decrypt and that the policy is enabled.
   
   
   
   
4. On the URL tab, you can select the Web Category or the Website list as well. In this example, they have been left on Any. Click Save.
   
   
   NOTE: Before an HTTP/HTTPS connection can be made, the end machine needs to perform DNS resolution of the URL. Since we have an implicit deny rule,  we'll need to allow DNS traffic as well.
   
   

To create the DNS related Security Policy

1. Navigate to Policy | Rules and Policies | Security Policy tab and click on Top at the bottom of the screen. This adds the new policy to the top of the list. You may need to adjust its priority based on other rules you have.
   
   
   
   
2. Give your policy a relevant name, then in the Source/Destination tab, you can modify fields such as source/destination zone, address and services, as well as user and geolocation settings. Select the destination Port/Services as 'DNS(Name Service)'.
   
   
   
   
3. Under App/URL/Custom Match tab leave everything on default setting.
4. Select the Default Profile as the Security Rule Action. Make sure that the Action is set to Allow and the policy is in enable state. Click Save.
   
   
   NOTE: This policy can also be created using the DNS protocol application signature, but Services is used in this example.
   
   

To create the allow web category related Security Policy

1. Navigate to the Policy | Rules and Policies | Security Policy tab and click on Bottom at the bottom of the screen. This adds the new policy to the bottom of the list. You may need to adjust its priority based on other rules you have.
   
   
   
   
2. Give your policy a  relevant name and then in the Source/Destination tab, you can modify fields such as source/destination zone, address and services, as well as user and geolocation settings.
   
   
   
   
3. In the App/URL/Custom Match tab, navigate to Match Operation and select the radio button for AND. To add a new  Web Category Group, select the pencil icon next to Web Category.
   
   
   
   
4. Give your new Web Category Group a relevant name. Add the required web categories to the right using the right arrow and click Save.
   
   
   
5. Under the Security Rule Action dropdown, click on the pencil icon to create a new Security Rule Action. 
   
   
   
6. Assign it a relevant name and you can set a lot of other security parameters, but the most important section for this setup is Content Filter. Navigate to the Content Filter tab and use the toggle button to turn on 'Enable Content Filtering'. The Content Filter Action should then be set to Allow.
   
   
   
   
7. Make any other desired changes to security options, then click Save .
8. In the Security Policy, make sure that the Action is set to Allow and the policy is in Enable state. Click Add.
   
   
   

• You're now able to access the websites that are part of the News and Search Engines and Portals category, such as google.com, cnn.com, etc.
  
  
• Upon visiting other websites, the following block page displays a message notifying the user that there's no matching policy to allow access to this website.