Bluetooth helper

https://github.com/ThomasHabets/bthelper

This is not an official Google product.

What is it

SSH Helper program so that you can SSH over bluetooth. This can be a useful second way in in case you have a raspberry pi with broken network or firewall config.

Related blog posts that describes a more full setup guide, including pairing.

Example usage assuming you've already paired devices

On the server

bt-listener -t localhost:22 -c 2

On the client

ssh -oProxyCommand="bt-connecter AA:BB:CC:XX:YY:ZZ 2" myhostname-console

Or in ~/.ssh/config:

Host myhostname-console
    ProxyCommand bt-connecter AA:BB:CC:XX:YY:ZZ 2

And then just ssh myhostname-console.

Example for console, not SSH

bt-listener -c 5 -e -- getty '{}' -E -H '{addr}'

'{}' and '{addr}' are treated special and should be written exactly as is.

bt-connecter -t AA:BB:CC:XX:YY:ZZ 5

Portability

Code currently relies on signalfd(), so it's Linux-only. Should be portable to FreeBSD and MacOSX using kqueue() with EVFILT_SIGNAL, but I don't have a mac to develop it on.

Alternatively we could switch to libevent.