Re: [TLS] New drafts: adding input to the TLS master secret

Marsh Ray <marsh@extendedsubset.com> Wed, 03 February 2010 02:24 UTC

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Date: Tue, 02 Feb 2010 20:24:45 -0600
From: Marsh Ray <marsh@extendedsubset.com>
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Subject: Re: [TLS] New drafts: adding input to the TLS master secret
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Martin Rex wrote:
> Marsh Ray wrote:
>> How big were you planning to make those symmetric keys anyway?
> 
> I would prefer to _not_ call anything "key" that is going to
> travel in the clear.  Personally, I always think of "keys" being
> secret or even private information.   I would prefer the term
> "random" or "entropy".

Sorry if this wasn't clear. I was referring to the actual keys that are
used for the symmetric algorithm. Negotiating these is one of the main
goals of the handshake process.

The point is that it seems like a bit of overkill to require
more than 448 bits of entropy to generate a key for AES-128.

- Marsh