registration with invalid `allowfrom` fails open about acme-dns

[joohoi]

I think you are on the right track here, and we should fail early. But from the UX perspective, I think what would be best way to handle this, would be to automatically add /32 bitmask if none is specified but the IP address itself is valid.

[joohoi]

This is now finally fixed. I opted to not to introduce magic I proposed in #43 (comment) . The only magic is removing [ and ] from the IP addresses as the net.ParseCIDR cannot handle that notation of IPv6 addresses.

[cpu]

from the UX perspective, I think what would be best way to handle this, would be to automatically add /32 bitmask if none is specified but the IP address itself is valid.

That sounds like a nice compromise 👍