def gssapi_authenticate(client_token: str):

    state = None
    try:
        rc, state = kerberos.authGSSServerInit("")
        if rc != kerberos.AUTH_GSS_COMPLETE:
            return None
        rc = kerberos.authGSSServerStep(state, client_token)
        if rc == kerberos.AUTH_GSS_COMPLETE:
            return dict(
                rc=rc,
                kerberos_token=kerberos.authGSSServerResponse(state),
                username=kerberos.authGSSServerUserName(state),
                servername=kerberos.authGSSServerTargetName(state),
            )
        elif rc == kerberos.AUTH_GSS_CONTINUE:
            return dict(rc=kerberos.AUTH_GSS_CONTINUE)
        else:
            return None
    except kerberos.GSSError:
        return None
    finally:
        if state:
            kerberos.authGSSServerClean(state)