Radius server can reply with Access-Challenge response which may
ask for more information in Reply-Message attribute. The request
is identified with the State attribute.
[ ] implement a RADIUS server side test that responds with the Access-Challenge for a specific username with a pre-defined challenge message and a response code
[ ] add a test that defines an IdP link for this user, sends a RADIUS request to ipa-otpd for the user, ensures ipa-otpd responds with the Access-Challenge message that sends back the same challenge we defined in the previous step
[ ] finally, add a RADIUS test that sends a RADIUS message back to ipa-otpd, containing the state from Access-Challenge and a response ('OTP code') as if responded by krb5 KDC. Ensure RADIUS test server returns success. Do the same for a negative test.
Radius server can reply with Access-Challenge response which may ask for more information in Reply-Message attribute. The request is identified with the State attribute.