Re: [TLS] DNS-based Encrypted SNI

Eric Rescorla <ekr@rtfm.com> Tue, 03 July 2018 03:58 UTC

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From: Eric Rescorla <ekr@rtfm.com>
Date: Mon, 2 Jul 2018 20:57:58 -0700
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To: Paul Wouters <paul@nohats.ca>
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Subject: Re: [TLS] DNS-based Encrypted SNI
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On Mon, Jul 2, 2018 at 8:53 PM, Paul Wouters <paul@nohats.ca>; wrote:

> On Mon, 2 Jul 2018, Eric Rescorla wrote:
>
>   https://tools.ietf.org/html/draft-rescorla-tls-esni-00
>>
>
> This is at a pretty early stage, so comments, questions, defect
>> reports welcome.
>>
>
>
>         This structure is placed in the RRData section of a TXT record as a
>         base64-encoded string.  If this encoding exceeds the 255 octet
> limit
>         of TXT strings, it must be split across multiple concatenated
> strings
>         as per Section 3.1.3 of [RFC4408].
>
> It is strongly recommended not to use TXT records. Why not use a new
> RRTYPE? Everything these days knows how to serve unknown record types
> (see RFC 3597). The only possibly exception is provisioning tools of
> small players, but this document starts of saying you basically need
> to be on a bulk hosting provider anyway. They can properly provision.
>

See:
https://github.com/ekr/draft-rescorla-tls-esni/issues/7#issuecomment-388531906

-Ekr