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Re: [TLS] SHA-1 vs. FNV-1

"Blumenthal, Uri - 0668 - MITLL" <uri@ll.mit.edu> Mon, 10 May 2010 17:09 UTC

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From: "Blumenthal, Uri - 0668 - MITLL" <uri@ll.mit.edu>
To: Eric Rescorla <ekr@rtfm.com>
Date: Mon, 10 May 2010 13:09:00 -0400
Thread-Topic: [TLS] SHA-1 vs. FNV-1
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Subject: Re: [TLS] SHA-1 vs. FNV-1
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On 5/10/10  12:58 , "Eric Rescorla" <ekr@rtfm.com> wrote:
> On Mon, May 10, 2010 at 9:55 AM, Blumenthal, Uri - 0668 - MITLL
> <uri@ll.mit.edu> wrote:
>> I see absolutely no need to justify use of non-crypto algorithms for
>> non-crypto purposes. "It's faster" would be all I'd care to say on the
>> subject.
> 
> The requirement is to explain why this is a non-crypto purpose. That's
> where the analysis comes in.

If there's even a hint that the usage could relate to security mechanisms -
doesn't it mean that SHA-1 MUST be forbidden, and at least SHA256 should be
mandated instead?

We seem to be juggling with this back and forth:

- either this is security-related - then SHA-1 is not suitable and MUST be
replaced with a currently-approved SECURE hash algorithm such as SHA256, or

- it is not security-related - then SHA-1 is too slow and SHOULD be replaced
with a faster algorithm.

Make up your mind - and mark SHA-1 dead in either case.
-- 
Regards,
Uri

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