Ask the user to generate and submit an address. Save it somewhere.
Later, when the user wishes to authenticate, generate a random cookie and present it to the user.
The user signs it using bitcoind signmessage <address> <cookie> and returns the result.
The device then verifies it using bitcoind verifymessage <address> <signature> <message>.
The address is to be saved and used as the key to the system right?
how do I generate this random cookie?
I take it that address variable is the address of the user right? the return value is the signature or the message?
This way of doing things though seems like using the address as the authenticating factor, and not a bitcoin/partherof. I was thinking of a system
where sending that specific bitcoin would grand access to the address for the system.