Feature request: "Kill Switch" option (Block all connections while disconnected from VPN server)

Prerequisites

• [Yes] Are you running the latest version of SoftEtherVPN?

SoftEther version: SoftEther VPN 4.0 (Ver 4.39, Build 9772) Component: [Client] Operating system: [Windows] Architecture: [64 bit, 32 bit]

Description

I have noticed that while I use SoftEtherVPN my VPN connections occasionally drop, so I request the "Kill Switch" feature. It will help people who work with sensitive data.

A kill switch is a security feature that protects your IP address in case you unexpectedly lose the connection to a VPN server.

In case the connection is interrupted, a kill switch blocks all external network traffic to and from your device until the connection is automatically re-established to the same VPN server.

This means that even though you can’t use the Internet until VPN reconnects, your IP address and DNS queries are safe from being exposed.

Permanent Kill Switch ensures that you do not accidentally connect to the internet without a VPN connection. Like the similar Kill Switch feature, Permanent Kill Switch will disable your internet connection during accidental VPN dropouts until a connection can be automatically re-established.

Unlike Kill Switch, it also prevents you from accidentally using the internet without the VPN turned on, and it will persist when you shut down and restart your system. You will not be able to connect to the internet if you manually disconnect the VPN without also disabling Permanent Kill Switch.

Whether you should use Kill Switch or Permanent Kill Switch will depend on your needs and threat model. Both Kill Switches will protect you against accidental VPN dropouts, but Permanent Kill Switch provides additional protection by ensuring you never accidentally access the internet without the VPN enabled.

Description is from here: https://protonvpn.com/support/what-is-kill-switch/ https://protonvpn.com/support/permanent-kill-switch-windows/

Expected behavior: I expect the menu where you can choose between options "to block outgoing connections while VPN is offline", "always block outgoing connections" or "not to block [...]". Except local connections like 192.168.x.x. It also should block all the connections after the system restart.

Actual behavior: I did not find such an option in SoftEtherVPN.

ProtonVPN Windows Application (https://github.com/ProtonVPN/win-app) has the button with the drop-down menu where you can choose to block all the connections to the internet when the connection to any VPN-server is dropped. You also can turn on the permanent block. It does block all the connections except local connections like 192.168.0.1.