Re: [TLS] TLS renegotiation issue

Nicolas Williams <Nicolas.Williams@sun.com> Thu, 05 November 2009 17:56 UTC

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Date: Thu, 5 Nov 2009 11:37:31 -0600
From: Nicolas Williams <Nicolas.Williams@sun.com>
To: Martin Rex <mrex@sap.com>
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Cc: tls@ietf.org
Subject: Re: [TLS] TLS renegotiation issue
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On Thu, Nov 05, 2009 at 06:38:10PM +0100, Martin Rex wrote:
> The "secure random challenges" in a TLS handshake that protect
> agains replay are the client.random and server.random.
> Admittedly they're larger (2*32 octets, fixed size) than the
> finished message (usually 12 octets, but depends on ciphersuite
> according to rfc5246 7.4.9.)
> 
> The client.random and server.random of a connection are already
> part of the official SecurityParameters (rfc5246 6.1.), but
> the finished message is not.

Guess what: the finished messages will have to become something that TLS
implementations export to applications.  There's no two ways about it
folks.

Nico
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