opennds

opennds places a captive portal in front of Internet access on a Linux system, showing a simple splash page while restricting access by default. Its API supports building more sophisticated authentication applications, and its small footprint and high performance set it apart from a basic splash-page gateway.

To use it, edit /var/snap/opennds/common/opennds/opennds.conf after installing the snap. Grant it access to firewall control, hardware observation, mount observation, network observation, and system observation with the corresponding sudo snap connect opennds commands.

Once those snap interfaces are connected, the opennds daemon starts automatically. The included opennds.ndsctl command provides a way to interact with the daemon. It requires Linux with snapd and targets x86_64 (amd64); the current version is 9.3.0, published by Oliver Grawert.