Technical Tip: How to restrict YouTube channels using video filtering

vhitnal · ‎04-28-2021

Description

This article describes how to allow YouTube channels while blocking all the other videos.

Only the videos from that channel will be reproduced.

Scope

FortiGate v7.0.11+.

Solution

With the video filter profile, it is possible to filter YouTube videos by channel ID for a more granular override of a single channel, user, or video.
The video filter profile is currently supported in proxy-based policies and requires SSL deep inspection.

It is recommended the use of YouTube API key, FortiGate extracts the video ID (vid) and tries to check the category and channel from the local cache. If there is no match from the local cache, it connects to the FortiGuard video rating server to query the video category. If the FortiGuard rating fails, it uses the videofilter.youtube-key to communicate with the Google API server to get its category and channel ID.

To create the YouTube key:

Go to console.cloud.google.com and log in with a Google Account.
Create a new project:
Give it name and select 'CREATE':

Select the Project, go to Navigation Menu -> APIs & Services -> Credentials:
Select 'Enabled APIs & services', and select 'ENABLE APIS AND SERVICES':
Select 'YouTube Data API V3'. Enable the API:
Select 'Credentials', then CREATE CREDENTIALS -> API Key:
Copy the API key and set it on FortiGate through CLI:

config videofilter youtube-key
edit 1
set key *****************
next
end

To configure a video filter from GUI.

Go to Security Profiles -> Video Filter and select 'Create New'. Add a profile name. In some cases, Video Filter might not be visible thus use the following commands if needed:

config system settings
set gui-proxy-inspection enable
end

In the YouTube Channel override list section, select 'Create New'. The New Channel Override Entry pane opens.

Collect Channel ID:
- On YouTube, go to YouTube Channel and select More information about this channel -> Share Channel -> Copy channel ID.

Enter a Channel ID and select an Action. To allow the channel, the actions 'Allow' or 'Monitor' can be used:

Select 'OK'.

The channel default action is 'Monitor', therefore all YouTube channels are allowed by default. For this example, it is necessary to change the default action to 'Block'.

This step must be done through CLI:

config videofilter youtube-channel-filter
edit 1
set name "VideoFilter" <----- Video Filter profile name.
set default-action block
config entries
edit 1
set action allow
set channel-id "UCRMwv-dKBzq9rH"
next
end

set override-category enable <----- To guarantee the channel action will override the Video Categories.
set log enable <----- Enable this option to generate logs.
next
end

All the YouTube channels will be blocked except the one added to the override list in Step 2.
Create the firewall policy:

Go to Policy & Objects -> Firewall Policy and select 'Create New'.
For Inspection Mode, select Proxy-based.
Enable 'Video Filter' and select the profile created.
WebFilter profile is not mandatory. If it is used, the category 'Streaming Media and Download' must be set to 'Allow' or 'Monitor'.
For SSL Inspection, select 'deep-inspection'. Note- In some scenarios, deep inspection will not work, but works with custom deep inspection.
To guarantee the SSL deep inspection is performed correctly, the QUIC protocol must be blocked. Enable 'Application Control Profile' and make sure QUIC is blocked: