go-win-netcontrol

About

go-win-netcontrol is a utility to allow unprivileged users to enable and disable network access (by enabling or disabling network interfaces) by using a password. This is useful for academic competitions that allow computers but require the Internet to be disabled. This utility has a minimal GUI that allows a teacher or coach to enter a password to enable or disable network access without needing administrator privileges.

How it Works

go-win-netcontrol is installed as a Windows Service running as the local system account. The service uses WMI to enable or disable all network interfaces. It listens on a unix socket for requests authenticated by an embedded password.

The same executable also runs as the GUI client, which communicates with the server over the unix socket. A teacher or coach enters the password and clicks a button to Enable or Disable network access.

Changing the Password

The password is embedded in the binary as an Argon2id hash. The default password is "password", which should obviously be changed. To generate a new hash, run:

HASHPASSWORD="<password>" go test ./hash -v

Use the hash output when building using the instructions below. You can change the Argon2id parameters (default time=2, memory=64MB, threads=1) by editing hash/hash_test.go.

Building

The easiest way to build go-win-netcontrol is with fyne-cross. Run:

fyne-cross windows -console -ldflags "-X main.passhashstr=<yourhash>"

The built binary will found in fyne-cross/bin/windows-amd64/go-win-netcontrol.exe.

Installing

Copy the built exe to the device and run (as an administrator):

.\go-win-netcontrol.exe service install

This will install and start the service, and place a shortcut to the GUI on the Public Desktop (e.g. for all users).

Service logs can be found in C:\Program Files\go-win-netcontrol\logs