[dns-operations] debug tool to generate DNS response?

[Yang Yu]

I am looking for a DNS server/debug tool that can respond to selected
queries with a crafted (potentially broken) response, like BadSSL for
DNS. Ideally all flags/codes should be customizable. This is quite
helpful for testing DNS clients.

For example, aaaa-servfail.example.org returns NoError for A but
ServFail for AAAA.

Thanks.


Yang