Tethering support (WiFi, Bluetooth, USB)

Tethering support in postmarketOS

Sharing your Internet connection with other devices is a common use case of phones. Several ways exist to share your Internet connection:

• WiFi: a WiFi hotspot where multiple devices can connect to. NetworkManager supports WiFi hotspot tethering.
• Bluetooth: Bluetooth PAN which is a Bluetooth profile to share your Internet connection. Bluetooth DNU is an alternative but obsolete and superseded by PAN. NetworkManager supports Bluetooth PAN as a client out-of-the box. You can connect an Android phone over Bluetooth and it will show up as a possible connection. However, postmarketOS needs the opposite: Bluetooth PAN server.
• USB: shows up as an USB ethernet adapter to the device. According to the postmarketOS wiki, this is already supported: https://wiki.postmarketos.org/wiki/USB_Internet but needs manual setup.

Supporting all these cases out-of-the-box will allow us to reach feature parity with Android and iOS which is a requirement for daily driving.

Improvements

• Configure Bluetooth PAN server, BlueZ has the necessary parts already, but needs configuration and network bridge stuff.
• Easy-to-setup USB tethering without manual configuration (!3819)
• GUI support to enable/disable various tethering options besides WiFi hotspot.