Re: [DNSOP] extension of DoH to authoritative servers

Tony Finch <dot@dotat.at> Thu, 14 February 2019 13:46 UTC

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Date: Thu, 14 Feb 2019 13:46:02 +0000
From: Tony Finch <dot@dotat.at>
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Subject: Re: [DNSOP] extension of DoH to authoritative servers
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Bjørn Mork <bjorn@mork.no>; wrote:
>
> My understanding of the reference to BCP195 from
> https://tools.ietf.org/html/rfc7858#section-3.2
> is that SNI support is required for all DoT implementations.
>
> It's simple to do with haproxy at least:
> https://www.haproxy.com/blog/enhanced-ssl-load-balancing-with-server-name-indication-sni-tls-extension/
>
> ...which incidentally also can be used to support DoT with *any* DNS
> server as backend.

I'm using nginx as my DoT and DoH front-end proxy
(https://github.com/fanf2/doh101/) and it looks
like I need to add ssl_preread support to get the SNI
https://nginx.org/en/docs/stream/ngx_stream_ssl_preread_module.html

I'm only really interested in logging it to see what the clients think
they are talking to - they are almost all Androids doing opportunistic
DoT.

Tony.
-- 
f.anthony.n.finch  <dot@dotat.at>;  http://dotat.at/
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