Wake on LAN: Support IPv6-only interfaces

[1e99]

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Is your feature request related to a problem? Please describe.
I have an interface on my OPNsense firewall that only has an IPv6 address and no IPv4 address, and I would like to broadcast Wake on LAN magic packets on it.

Describe the solution you'd like
I would like the Wake on LAN plugin to consider IPv6 addresses on interfaces and send broadcast packets to an iPv6 multicast address (e.g. ff02::1) if an IPv6 address is available.

Describe alternatives you've considered
Do not send an IP header at all, but rather send a raw ethernet frame with the magic packet as the payload.

Additional context
None

[Monviech]

You have to check if the wol package supports this. If not, you have to ask upstream if an IPv6 mode can be implemented.

https://man.freebsd.org/cgi/man.cgi?query=wol

[1e99]

The wol upstream package does not seem to support IPv6 from my quick source code browse here. However seeing like the last commit was 22 years ago, I doubt the upstream package will get an IPv6 update.

It might be worth implementing a custom Wake on LAN sender in PHP using PHPs socket and socket_sendto functions as an alternative?

[Monviech]

One if the constraints here is that a plugin must use an available upstream port as its base.

Custom implementations cannot be reasonably maintained in the plugin scope.

If there is an alternative upstream offering in freebsd ports, or somebody extends wol upstream, this plugin here could be extended.

[1e99]

I did not find an upstream port that actually supports IPv6 multicast addresses. net/wakeonlan has a pull request, but that has been open for 5 years. net/p5-Net-Wake does not support IPv6 at all, and there is no pull request.

I will look into creating a wake-on-lan port that supports both IPv4 and IPv6. I've never done that so it will probably take some time.

[Monviech]

If you want to build something, lang/go is probably a good choice. I've recently built a tool from scratch with gopacket/layers and it was generally a very nice experience.

Good luck :)