Re: [TLS] Resuming a session as part of a renegotiation.

Michael D'Errico <mike-list@pobox.com> Thu, 19 September 2013 17:05 UTC

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Date: Thu, 19 Sep 2013 10:05:35 -0700
From: Michael D'Errico <mike-list@pobox.com>
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To: Fabrice Gautier <fabrice.gautier@gmail.com>
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Subject: Re: [TLS] Resuming a session as part of a renegotiation.
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Fabrice Gautier wrote:
> 
> Is there anything in the TLS RFCs that prohibit using a resumed
> session as a result of a renegotiation handshake ?

No.

> I haven't found anything, but I can't think of an interesting use case
> for that behavior either.

Not sure if it's interesting, but you get fresh session keys.

One possible use case: if you negotiated a block cipher with a
small internal state and are sending large quantities of data,
security might be improved by periodically renegotiating.

Mike