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In reply to Comment by Reader Arkadiy Tetelman

Andrew Ayer on 2020-01-05 at 23:40:

Hi Arkadiy - I'm glad my post was useful!

You wrote:

For instance I could make a request to the ipv6 address ::ffff: and access your cloud provider metadata service.

I just tried this and my code properly rejects ::ffff:

My code works properly because is listed in reservedIPv4Nets, and Go's IPNet.Contains considers IPv4 and IPv4-mapped IPv6 addresses to be equivalent. Therefore, there is no need to separately enumerate reserved IPv4 addresses in mapped IPv6 form.


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