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

Simon Josefsson <simon@josefsson.org> Mon, 10 May 2010 17:36 UTC

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From: Simon Josefsson <simon@josefsson.org>
To: Eric Rescorla <ekr@rtfm.com>
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Date: Mon, 10 May 2010 19:32:35 +0200
In-Reply-To: <AANLkTilFDKOzbxZF-h0N0gHBLNW3BIS_Nf7e99VfdjkC@mail.gmail.com> (Eric Rescorla's message of "Mon, 10 May 2010 10:00:14 -0700")
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Cc: "tls@ietf.org" <tls@ietf.org>
Subject: Re: [TLS] SHA-1 vs. FNV-1
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Eric Rescorla <ekr@rtfm.com> writes:

> On Mon, May 10, 2010 at 9:57 AM, Simon Josefsson <simon@josefsson.org> wrote:
>> Eric Rescorla <ekr@rtfm.com> writes:
>>
>>> Again, SHA-1 is simply the default hash algorithm people use at this
>>> point.
>>
>> Define "people"?
>
> Uh, the hash algorithm that's by far in the widest use? Seriously, is
> there some question about this in a world where we only added support
> for SHA-256 to TLS 1.2 about a year ago?

Yes, since I believe people are using SHA-1 in the same way they use MD4
and MD5 today: for interoperability with an deployed base.  Thus, I fail
to understand any argument why SHA-1 would be a more suitable algorithm
than MD5 if the only explanation is "wide use".

I'm not sure discussion is adding anything but subjective opinions at
this point.  I know that implementations of the extension has been
stalled because of this discussion.  Perhaps it is time for a consensus
call to resolve this aspect.

/Simon

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