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Re: [TLS] Deprecate SHA1 for signatures in TLS 1.3 (was Re: TLS 1.3 draft-07 sneak peek)

Karthikeyan Bhargavan <karthik.bhargavan@gmail.com> Tue, 07 July 2015 16:16 UTC

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From: Karthikeyan Bhargavan <karthik.bhargavan@gmail.com>
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Date: Tue, 07 Jul 2015 12:16:04 -0400
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To: "Salz, Rich" <rsalz@akamai.com>
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Subject: Re: [TLS] Deprecate SHA1 for signatures in TLS 1.3 (was Re: TLS 1.3 draft-07 sneak peek)
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> Let's distinguish between two different uses of SHA-1:
> 
> 1. In certificates.
> 2. In TLS signatures.

I was recommending getting rid of (2).
Getting rid of (1) would be nice, but I gather it relies on developments outside TLS.


> On 07 Jul 2015, at 12:13, Salz, Rich <rsalz@akamai.com> wrote:
> 
>> This PR seems to prohibit use of SHA-1 for certificates as well, which I'm not sure
>> is wise. I suggest we put this on the agenda for Prague.
> 
> Yes, I didn't intend to outlaw SHA1 certs; perhaps a bit more finesse is required.:)

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