Re: [dane] DANE Testing

Viktor Dukhovni <viktor1dane@dukhovni.org> Fri, 21 February 2014 22:41 UTC

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Date: Fri, 21 Feb 2014 22:41:28 +0000
From: Viktor Dukhovni <viktor1dane@dukhovni.org>
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Subject: Re: [dane] DANE Testing
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On Fri, Feb 21, 2014 at 04:54:04PM -0500, Stephen Nightingale wrote:

> >So results from GnuTLS DANE verification can be misleading.
>
> I should point out that I am not using GnuTLS idea of DANE
> verification. I'm getting the cert chain passed up and doing my own
> DANE verification. For this purpose I had to modify the
> python-gnutls-1.2.5 interface to GnuTLS, to pass in a certificate
> chain, since in the download it only passes in a single end cert.

OK, but with DANE-TA(2) now you have the rather difficult task of
performing PKIX validation of a complete trust chain.  I forget
what your approach was for this.  Are you checking all the expiration
dates, signatures, basic constraints, name constraints, pathlength
constraints, performing name checks, ... That's a lot of difficult
code.

-- 
	Viktor.