feat: add receive interface information

[jclab-joseph]

For libp2p/go-libp2p#2661

In the case of link-local address, the interface must be bound.
Include the received interface in a ServiceEntry.

Additionally, when using a bridge, slave interfaces should not be used:
https://github.com/libp2p/zeroconf/pull/35/files#diff-25a7cf08cc8fc8eb57475835cc380524de2fd1215cda9c6915132ae86dbd80a7R117-R121

[marten-seemann]

I don’t understand this PR. Can you please explain what you’re trying to achieve?

We avoid making changes to this repo unless absolutely necessary.

[jclab-joseph]

@marten-seemann

Described at libp2p/go-libp2p#2660 (comment)

As an example, an IoT node before IP is set can use it to communicate via p2p.
IPv6 link-local address can be used even if a static IP is not set.
In this case, you can communicate by searching for each other using mdns, etc. within the local network.

[marten-seemann]

I don’t understand how that would work. What’s the address you’d advertise in that case? Can you give an example here?

[jclab-joseph]

@marten-seemann

This is a fully working example.
https://github.com/jclab-joseph/libp2p-link-local-demo/tree/ipv6-link-address-with-mdns

what has changed: https://github.com/jclab-joseph/libp2p-link-local-demo/pull/1/files

mdns packet:

After finding out the received interface using ifIndex or Zone, connect to /ip6zone/{interface name}/{txt}.

[marten-seemann]

This seems to be a fix for grandcat#51.

Since we're only maintaining a fork of zeroconf to support some API changes, we won't merge this PR, unless the fix is upstreamed to the upstream repo. @jclab-joseph, please open a PR in the original repo, and once it's merged there, we can cherry-pick that commit onto our fork here.

[jclab-joseph]

grandcat#117