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Re: [TLS] FNV versus SHA-1 in cached info

Simon Josefsson <simon@josefsson.org> Fri, 07 May 2010 11:27 UTC

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From: Simon Josefsson <simon@josefsson.org>
To: Stefan Santesson <stefan@aaa-sec.com>
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Date: Fri, 07 May 2010 13:24:18 +0200
In-Reply-To: <C809C29C.A99B%stefan@aaa-sec.com> (Stefan Santesson's message of "Fri, 07 May 2010 13:14:04 +0200")
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Cc: "tls@ietf.org" <tls@ietf.org>
Subject: Re: [TLS] FNV versus SHA-1 in cached info
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Stefan Santesson <stefan@aaa-sec.com> writes:

> I would not have any problem with using SHA-1 if it could be used with no
> agility what so ever. But I seriously doubt that this will be accepted and
> for that reason I would like to keep FNV.

I also prefer to use FNV here.

Organizations are performing review of how MD5 and eventually SHA-1 are
used in their code bases, and this is costly.  If we know when designing
a protocol that the normal cryptographic properties are not essential,
and that an algorithm like FNV will suffice, it saves everyone the costs
associated with that review.  This is only one argument for FNV, there
are others.

I wish we used something like FNV instead of SHA-1 in SASL GS2, the use
there also do not require cryptographic properties.

/Simon

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