Re: [TLS] Wrapping up cached info

Stefan Santesson <stefan@aaa-sec.com> Thu, 27 May 2010 16:00 UTC

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Date: Thu, 27 May 2010 17:59:57 +0200
From: Stefan Santesson <stefan@aaa-sec.com>
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Subject: Re: [TLS] Wrapping up cached info
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I will try to provide a revised draft next week, incorporating the "agreed"
changes.

/Stefan


On 10-05-27 5:47 PM, "Nicolas Williams" <Nicolas.Williams@oracle.com> wrote:

> On Thu, May 27, 2010 at 10:38:09AM -0500, Brian Smith wrote:
>> Martin Rex wrote:
>>> I think that should be described in the Security Considerations that
>>> a client or client&server that perform renegotiation for the purpose
>>> of client identity protection may want to tag their cached values
>>> so that when that value was established on an encrypted handshake,
>>> it is not going to be proposed by the client on a successor
>>> plaintext handshake.
> 
> Yes.
> 
>> How would the server indicate this to the client?
> 
> There's no need for the server to indicate anything to the client here.
> 
> If a client wouldn't attempt user authentication w/o re-negotiation then
> it shouldn't send a hash of its user cert / cert chain in the initial
> handshake.  If a server considers user cert TAs to be confidential
> (highly unlikely, but let's suppose) then the server shouldn't list
> their hashes in initial handshakes.  It's that simple.
> 
> Nico