btdaemon

A tiny program for enabling / disabling Bluetooth based on the SSID your host is connected to.

Why?

Bluetooth is susceptible to a number of security issues. To avoid those, this program only enables Bluetooth when your host is connected to a known network.

It's convenient to have Bluetooth enabled even when devices aren't connected when using devices that power down (and disconnect) while idle (like mice).

Caveats

I wrote this program for myself. Which means there's a few bits that are hardcoded:

• You must have blueutil installed.
• The airport command must be present and located at /System/Library/PrivateFrameworks/Apple80211.framework/Resources/airport.
• Logs are always printed to /var/log/net.codeviking.btdaemon/stdout.log.

Installation

Build a binary:

go build -o btdaemon ./main.go

Put it in /usr/local/bin:

sudo mv btdaemon /usr/local/bin/.

Put the plist file in /Library/LaunchAgents:

sudo cp net.codeviking.btdaemon.plist /Library/LaunchAgents

Make a directory for the daemon's logs. The permission juggling is important, as the agent runs as your user:

sudo mkdir /var/log/net.codeviking.btdaemon
sudo chown $(id -u -n):$(id -g -n) /var/log/net.codeviking.btdaemon

Create a file with a list of trusted ssids:

sudo mkdir /etc/btdaemon
sudo echo "<TrustedSSID> >> /etc/btdaemon/trust.txt

Load and start the daemon:

launchctl load net.codeviking.btdaemon.plist

See what it's doing:

tail -f /var/log/net.codeviking.btdaemon/stdout.log

To stop the daemon run:

launchctl unload net.codeviking.btdaemon.plist