Re: [dnsext] BADVER/FORMERR

["Michael Sheldon" <[e-mail]>]

> -------- Original Message --------
> Subject: Re: [dnsext] BADVER/FORMERR
> From: Dick Franks <[e-mail]>
> Date: Tue, November 15, 2011 11:32 am
> To: Ray Bellis <[e-mail]>
> Cc: dnsext <[e-mail]>
> 

> Part of Mark A's argument is that the semantics for QDCOUNT = 0 should
> be considered well defined because no standard query processing is
> involved if there is no question to process.

Really? Exactly what part of any RFC defines what should be returned on
a QUERY where QDCOUNT == 0? Unless you found something I haven't seen,
it's not only not well-defined, it's not defined at all. 

> Furthermore, he noted that an empty question section is (trivially)
> parsable, and cites three plausible scenarios where such a query might
> be useful.

He defines circumstances where he can learn things from the server by
deliberately sending invalid data, thus eliciting an error message. So
we've already defined that he's deliberately sending contextually bogus
data. The question is, if everything in the EDNS section is correct,
what would the response be to QDCOUNT=0? Unless you can convince me
there is a valid non-error response to this, I see nothing wrong with
returning a response based on the first error I find and discontinuing
parsing at that point. In my opinion, a query with no query is a format
error. Any further errors beyond that point are irrelevant.

My suggestion Mark, is to put some kind of question in the packet, the
size difference is frankly insignificant.


Michael Sheldon
Dev-DNS Services
GoDaddy.com