Implement CAA resource record

hanazuki commented 4 months ago

This patch implements handling of CAA resource records defined by RFC8659. Based on https://github.com/ruby/ruby/pull/1732 by @aeris, with tests added and some changes:

There are no known deployment of CAA records outside of IN (Internet), but the RFC does not state that CAA records are class-specific. Thus CAA class is defined as a class-independent RRType.
CAA class stores flags field (a 1-octet bitset) as an Integer. In this way it's easier to ensure the encoded RR is in the valid wire format.

hanazuki commented 4 months ago

hsbt commented 4 months ago

Yes, Windows platform failed sometimes with Errno::EACCES: Permission denied - bind(2) for "127.0.0.1" port 53896.

aeris commented 4 months ago

:heart:

ruby / resolv