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Re: [TLS] Certificate validation can of worms

Nico Williams <nico@cryptonector.com> Tue, 08 April 2014 19:06 UTC

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Date: Tue, 08 Apr 2014 14:06:47 -0500
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From: Nico Williams <nico@cryptonector.com>
To: Santosh Chokhani <SChokhani@cygnacom.com>
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Cc: "tls@ietf.org" <tls@ietf.org>
Subject: Re: [TLS] Certificate validation can of worms
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On Tue, Apr 8, 2014 at 1:40 PM, Santosh Chokhani <SChokhani@cygnacom.com> wrote:

I agree with what you say, but there is one area where I think name
constraints could be improved: when a certificate has no
subjectAlternativeNames, or only directoryNames when it does, and
those names are RFC6125-style, then if the CA certs in the validation
path have dNSName name constraints then those should be applied to the
CN RDNs of the subjectName and/or dirname SANs that bear the
domainnames.  To my knowledge this isn't codified, but correct me if
I'm wrong.

Nico
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