Re: [TLS] Simplifying signature algorithm negotiation

Kurt Roeckx <kurt@roeckx.be> Wed, 20 January 2016 11:50 UTC

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Date: Wed, 20 Jan 2016 12:50:38 +0100
From: Kurt Roeckx <kurt@roeckx.be>
To: David Benjamin <davidben@chromium.org>
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Subject: Re: [TLS] Simplifying signature algorithm negotiation
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On Tue, Jan 19, 2016 at 10:08:45PM +0000, David Benjamin wrote:
> On Fri, Jan 15, 2016 at 10:13 PM Brian Smith <brian@briansmith.org>; wrote:
> 
> > David Benjamin <davidben@chromium.org>; wrote:
> >
> >> (Whether such certificates exist on the web is probably answerable via CT
> >> logs, but I haven't checked.)
> >>
> >
> > Me neither, and I think that's the key thing that would need to be checked
> > to see if my suggestion is viable.
> >
> 
> Looks like DigiCert's EC intermediates are P-384 and they sign SHA-256 more
> often than not.
> https://crt.sh/?CN=%25&iCAID=1516

This is my current count of ECDSA based signatures:
 ECDSA_SHA256        | 1970793
 ECDSA_SHA384        |      53

(That's all valid certificate I know about, most of those have
expired.)


Kurt