One of the test from DNS Compliance testing validates that if the opcode
is not supported, a NOTIMPL rcode is returned.
e0884144dd/genreport.c (L293)
This diff makes the default acceptfunc support this case and reply with
NOTIMPL instead of FORMERR.
* RFC 1996 allows SOA in answer in notify
The answer section of a notify can contain a SOA record that we should
not ignore in the DefaultAcceptFunc.
* End sentence
Signed-off-by: Miek Gieben <miek@miek.nl>
* Don't reject Nscount > 0
IXFR request could have a SOA RR in the NS section
RFC 1995, section 3: https://tools.ietf.org/html/rfc1995
* Only one RR in the NS section is acceptable
* Remove URL from comment
Generalize the srv.Unsafe and make it pluggeable. Also add a default
accept function that allows to discard malformed DNS messages very early
on. Before we allocate and parse anything furher.
Also re-use the client's message when sending a reply.
Signed-off-by: Miek Gieben <miek@miek.nl>
