hardware security keys and command line Linux?

[Linux for blind general discussion]

Hi folks,
Anyone successfully using a hardware security key in a command line Linux 
environment?
The option  came up on the google accessibility  list when discussing 
future changes to gmail access.
I personally admit to wondering in edition if one could use such a key on a 
shell focused machine, providing protection by  something like a fixed IP 
address, and thereby access for all users of said shell setup?
Thanks,
Karen