Re: [TLS] [tls13-spec] relax certificate_list ordering requirements to match current practice (#169) (Martin Rex) Tue, 12 May 2015 22:38 UTC

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Date: Wed, 13 May 2015 00:38:38 +0200
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Subject: Re: [TLS] [tls13-spec] relax certificate_list ordering requirements to match current practice (#169)
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Ryan Sleevi wrote:
> On Tue, May 12, 2015 2:38 pm, Martin Rex wrote:
>>  One of the worst problems in your proposed text is the replacment
>>  of the term "self-signed [...] root certificate authority" with
>>  two bogus occurrences of the term "trust anchor".
>>  Trust anchor is a _strictly_ local concept, so this term
>>  MUST NOT be used in the description of the TLS Certificate PDU.
>>  self-signed root certificate authority is a simple technical term,
>>  that does *NOT* imply trust by any party.
> You will find the reasoning already provided in past messages for why this
> proposed terminology change. "self-signed root certificate authority" is,
> unquestionably, NOT a simple technical term (considering how many times it
> has confused people, I should think this obvious).

Then add the line of text from rfc5280 or X.509 that explain what a
self-signed CA certificate is.

> Please do re-read the
> message is which I provided the justification for this change, and
> hopefully provide counter-factual evidence if there is any.

I is *IMPOSSIBLE* to justify the use of "trust anchor" here.

> Considering that "trust anchor" is a term extensively used in RFC 5280,

rfc5280 explicitly describes "trust anchor" to have only a *local* meaning!
see rfc5280, section 6.2 (which I previously quoted).

> I also fail to understand your objection about it being a "local only"
> concept. This is entirely in line with the current language where you can
> omit certificates that you know your peer does not need.

The Certificate handshake message PDU is produced by one TLS peer (sender)
and consumed/interpreted by the *OTHER* TLS peer.  But the concept of
a trust anchor is a thoroughly local issue, so the use of the terminology
for the TLS Certificate PDU is provably incorrect for at least one TLS peer.