Awesome! Glad this worked (although I had no doubt it would aside from the potential caveats I mentioned).
I don't know if it has any kind of special name... if you read up on the firewall, this is just one of the standard features. This is one of the main reasons why the devices can reach the internet, but the internet cannot reach your devices... The default condition allows forwarding from the lan zone > wan zone. But the reverse is not allowed.
Yeah.... some firewalls require additional rules. For example, doing this on EdgeOS (another routing OS) is still simple, but requires a rule that allows the forwarding from one network to another and then an accompaying rule for "established and related" connections to return. But yeah, on the OpenWrt "zone based firewall" it's really that simple.
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