Re: [Doh] [Ext] A question on the mix of DNS and HTTP semantics

Andrew Sullivan <ajs@anvilwalrusden.com> Mon, 19 March 2018 15:22 UTC

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From: Andrew Sullivan <ajs@anvilwalrusden.com>
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Subject: Re: [Doh] [Ext] A question on the mix of DNS and HTTP semantics
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On Mon, Mar 19, 2018 at 03:09:58PM +0000, Stephane Bortzmeyer wrote:
> On Mon, Mar 19, 2018 at 10:42:42AM +0000,
>  Mike Bishop <mbishop@evequefou.be>; wrote 
>  a message of 24 lines which said:
> 
> > There's a reasonable argument that if Content-Type is
> > application/dns-udpwireformat, it should be processed by the DNS
> > client regardless of the HTTP status code.
> 
> It can be dangerous, no? If the status code is 500, it means there was
> a serious problem in the server, the content may be, for instance,
> truncated.

If it were actually truncated, wouldn't the message have a TC bit set?
If the message contained is short of the full UDP message, wouldn't
the client-side processor be able to tell because the counts of actual
RRs wouldn't match the header section counters?

Best regards,

A
-- 
Andrew Sullivan
ajs@anvilwalrusden.com