Add support for DNS resolution on non-port 53 to DnsDiscovery

[zh522130]

I do have this need because my port 53 is required for other DNS services. Currently, I have modified the code locally and validated it. If others have a similar need, I can submit a PR.

[zh522130]

This is not an issue; I just want to confirm whether I should submit this PR.

[dignifiedquire]

which part of the code are you talking about, iroh-dns-server?

[zh522130]

which part of the code are you talking about, iroh-dns-server?

yes

[dignifiedquire]

sure, a PR would be appreciated

[zh522130]

There was an issue with my previous description. The actual situation is that the iroh-dns-server can run on non-port 53, but DnsDiscovery does not support resolution on non-port 53. so this is related to iroh-net

[flub]

I think this is already possible with iroh_net::endpoint::Builder::dns_resolver: it allows you to construct your own resolver client that the endpoint will use, including the DnsDiscovery feature. You'd use something like hickory_resolver::config::ResolverConfig::add_name_server to set custom connection details for your DNS server.

[zh522130]

I think this is already possible with iroh_net::endpoint::Builder::dns_resolver: it allows you to construct your own resolver client that the endpoint will use, including the DnsDiscovery feature. You'd use something like hickory_resolver::config::ResolverConfig::add_name_server to set custom connection details for your DNS server.

I have previously tested the dns_resolver, and the main issue is that the relay also uses dns_resolver, which cannot resolve the relay address. It's possible that I'm using it incorrectly, I will continue to research this. Once the tests pass, I'll close this issue.

[zh522130]

@flub Thank you. I've implemented custom port resolution through dns_resolver.

Should anyone need it, you can refer to the create_default_resolver function in dns.rs. You simply need to add a DNS service with a custom port using config.add_name_server().