Exercising Challenge/Response code path in pam client?

[Richard Perrin]

On Thu, Sep 22, 2016 at 3:40 PM, Alan DeKok <aland at deployingradius.com> wrote:
>   You need an authentication protocol which will do challenge-response.  Most won't.
>
>   In version 3, you can implement full challenge-response in "unlang".
>
>   So... upgrade.

Any pointers on how to do the unlang challenge-response?

I've build and run 3.0.11, and have successful authentication
happening with the following minimalistic config file in
sites-enabled:

server port18121 {
        listen {
                ipaddr = *
                port = 18121
                type = auth
        }
        authorize {
                update control {
                        Cleartext-Password := "radiuspass"
                }
                pap
        }
        authenticate {
                pap
        }
}

Not sure what's simplest to replace pap with in order to generate the
challenges.

- Richard