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Re: [TLS] Renegotation redux

Juho Vähä-Herttua <juhovh@iki.fi> Mon, 14 April 2014 15:04 UTC

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From: Juho Vähä-Herttua <juhovh@iki.fi>
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Date: Mon, 14 Apr 2014 18:04:14 +0300
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To: Watson Ladd <watsonbladd@gmail.com>
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Subject: Re: [TLS] Renegotation redux
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> On 14.4.2014, at 17.48, Watson Ladd <watsonbladd@gmail.com> wrote:
> 
> Dear all,
> 
> Are there any users of renegotiation beyond authentication with client
> side certificates? In particular has anyone come up with a use for
> changing the claimed identity of the server?

I've been under the impression that renegotiation can be used to keep the connection open when the encryption is based on nonces and client/server runs out of usable nonces. The current counters are large enough that this is unlikely to happen, but if some crypto defines smaller nonces it might be a problem.

Disallowing renegotiation would leave both parties with no other choice than hanging up the connection.


Juho

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