Implementing a multi-round trip preauthentication method

[Alejandro Perez Mendez]

Hello,

I'm interested in implementing a multi-round trip pre-authentication
method for Kerberos. Could you please indicate me what are the basic
steps to be followed, what files should I touch, etc?

I've seen that preauth_plugin.h defines a set of callbacks to implement
preauthentication plugins, but it is not clear to me how this would have
to be done, especially for a multi-round trip method.

I would really appreciate any help on this topic.

Best regards,
Alejandro