Thinking about MFA infrastructure

[Branko Čibej]

Hi all,

I've been digging into Serf's support for various authentication schemes 
and I notices something that looks like a bit of a limitation.

Unless I'm much mistaken, there's space for only one authentication 
baton in Serf's context. It would seem that this is rather a blocker for 
implementing multi-factor authentication flows, for example, Basic + 
OTP, where the server would first require basic credentials and then, if 
those were correct, go on to issue an OTP challenge.

It seems to me that a simple solution for that would be to store an 
authn baton per scheme, but I know on the close order of nothing about 
the possible side effects.

Yeah, I'm starting small, I have no wish to implement OAuth2 flow any 
time soon. Still, a bit of insight from the knowledgeable would be welcome.

-- Brane