Re: [TLS] Justification

Nicolas Williams <Nicolas.Williams@oracle.com> Wed, 12 May 2010 18:11 UTC

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Date: Wed, 12 May 2010 12:46:29 -0500
From: Nicolas Williams <Nicolas.Williams@oracle.com>
To: Marsh Ray <marsh@extendedsubset.com>
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Cc: Simon Josefsson <simon@josefsson.org>, "Kemp, David P." <DPKemp@missi.ncsc.mil>, tls@ietf.org
Subject: Re: [TLS] Justification
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On Wed, May 12, 2010 at 11:59:38AM -0500, Marsh Ray wrote:
> Come to think of it, that may be the best argument of all in favor of a
> strong hash function: it enables the cache to be kept for arbitrary
> lengths of time without special protections or serious security
> considerations.

It's not the only solution that does.  I just proposed using URLs to
name cacheable objects.  Objects at any URLs would never change; to
change the object you'd change the URL.

The key to making the protocol secure is to add the cached objects as
extra inputs to the Finished message computation.