Re: [DNSOP] Proposal for a new record type: SNI

"John Levine" <johnl@taugh.com> Mon, 20 February 2017 21:19 UTC

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Date: 20 Feb 2017 21:19:25 -0000
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From: "John Levine" <johnl@taugh.com>
To: dnsop@ietf.org
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Subject: Re: [DNSOP] Proposal for a new record type: SNI
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In article <alpine.DEB.2.11.1702201458030.23970@grey.csi.cam.ac.uk> you write:
>Would it be easier or harder, instead of adding a new SNI RRtype, to use
>DANE TLSA records to identify the server's cert or key, and use a
>variation of TLS SNI to request the cert by digest instead of by name?

I don't see how that would help.  Using passive DNS it's easy to find
all the names that point to a server, which makes it easy to get all
of the TLSA records for those names so the bad guy knows the hashes.

R's,
John