Maintained by: NLnet Labs

[Unbound-users] bogus resolution with forwarding and DLV

Tony Finch
Wed Feb 4 12:23:23 CET 2015


Jan Včelák <jan.vcelak at nic.cz> wrote:
>
> After inspecting responses from BIND and Unbound, I belive this is
> caused by BIND adding a NS RRs without a RRSIG added into the authority
> section of the answer.

> I don't know why BIND is adding the NS into the answer. But I think this
> is really a problem of BIND, as per
> http://tools.ietf.org/html/rfc4035#section-3.1.1:
>
> >    o  When placing a signed RRset in the Authority section, the name
> >       server MUST also place its RRSIG RRs in the Authority section.
> >       The RRSIG RRs have a higher priority for inclusion than any other
> >       RRsets that may have to be included.  If space does not permit
> >       inclusion of these RRSIG RRs, the name server MUST set the TC bit.

I think you are right it is a bug in BIND. I also think Unbound should
discard the incomplete RRset rather than failing to return a response.


It looks like the bug in BIND is due to a combination of an unsigned NS
RRset that came from a referral, and validation turned off. I can't
reproduce the bug with my validating resolvers with a normal query but it
does occur if I set the CD bit.

Are you going to send this in to bind9-bugs at isc.org or would you like me
to do it?

Tony.
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