Re: [TLS] Encrypted SNI

Paul Wouters <paul@nohats.ca> Wed, 04 July 2018 03:31 UTC

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Date: Tue, 3 Jul 2018 23:31:28 -0400 (EDT)
From: Paul Wouters <paul@nohats.ca>
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Subject: Re: [TLS] Encrypted SNI
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On Tue, 3 Jul 2018, Eric Rescorla wrote:

> but in this particular case, can't enterprise just strip ESNI records from DNS?

Not if endnodes within the enterprise also use DNSSEC. Unless you want
the enterprise to run authoritative fake DNSSEC for the entire world.

It also requires installing internal trust anchors, which is something
you pushed back hard on with draft-ietf-ipsecme-split-dns

One way this could be done is if draft-ietf-dnsop-dns-rpz finally goes
RFC, so IETF gains change control of a bis document, where we define the
filtering to move the filtered record from the additional to the authority
section, so the filtering can be detected yet DNSSEC verified.  But it
seems draft-ietf-dnsop-dns-rpz is being kept in draft state forever,
which basically prevents us from fixing this.

Paul
ps. also note stripping a ESNI RRTYPE is easier than stripping _some_
TXT records :)