options to bypass domain validation?

[ibigbug]

I was able to build a "bad name" with rr::Name::from_str_relaxed for example: some_domain.understore

however when I use the client to exchange the message I got this error

proto error: Label contains invalid characters: Err(Errors { invalid_mapping, disallowed_by_std3_ascii_rules })

does it mean the client is validating the domain and failing with invalid char - is there a way to bypass the validation?

[djc]

This looks like an error from the idna crate. I'm not sure why/where that gets invoked, though. Can you provide some sample code for how your Name is passed to the client code you mention?

[ibigbug]

hi @djc thanks for you response. actually I was being misleading - I had two implementations of my DNS client and the manual crafting with bad names is actually working fine.

and the error was actually returned by the default system client, and the minimum repro is :

      let resolver = TokioAsyncResolver::tokio_from_system_conf().unwrap();
        let response = resolver.lookup_ip("some_under_store.com").await;
        assert!(response.is_err());
        assert_eq!(
            response.unwrap_err().to_string(),
            "proto error: Label contains invalid characters: Err(Errors { invalid_mapping, disallowed_by_std3_ascii_rules })"
        );

and looking at the options here https://docs.rs/trust-dns-resolver/latest/trust_dns_resolver/config/struct.ResolverOpts.html

I also don't see it's able to bypass the validation - any thoughts?

[djc]

So AsyncResolver::lookup_ip() takes an impl IntoName. If you use Name::from_str_relaxed() and then pass the result into lookup_ip(), I think this will work?

See also discussion in #1904, and if you want to help with #1919 that would be great, too!