Re: [dnsext] BADVER/FORMERR

[Olafur Gudmundsson <[e-mail]>]

On 10/11/2011 21:50, Mark Andrews wrote:
>
> I was looking for a good way to test for EDNS support and hacked
> dig to send out a empty question section when the EDNS version was
> set to 255 and got what I believe to be incorrect responses from K
> and L.  EDNS version processing is supposed to take precedence over
> examining the query section as the EDNS version can influence the
> interpretion of the question section.  I believe the correct response
> should be BADVERS.  Adding a question elicited BADVERS.
>
> Do others agree with my interpretion of rcode precedence?
>

<no hat>
Formerr is perfectly valid return code.
It is the first error you detect and you can stop processing
right then.
(This assumes that the QR=0)

Reasoning: You sent a question that is not a real question
I see nothing in ENDS0 rfcs that say you need to look into the
opt record if the DNS packet is malformed, QR=0 and QDCOUNT=0
is malformed packet IMHO.

	Olafur