Re: [TLS] permitted client behaviour when rejecting renegotiation

Nikos Mavrogiannopoulos <nmav@gnutls.org> Wed, 20 January 2010 15:56 UTC

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Date: Wed, 20 Jan 2010 16:56:04 +0100
From: Nikos Mavrogiannopoulos <nmav@gnutls.org>
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Cc: tls@ietf.org
Subject: Re: [TLS] permitted client behaviour when rejecting renegotiation
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Martin Rex wrote:
> Considering the guidance in draft-ietf-tls-renegotiation-03.txt
> and the specification of HelloRequest starting with rfc-2246 (TLSv1.0)
> http://tools.ietf.org/html/rfc2246#section-7.4.1.1
[...]
> Question to implementors: what will your TLS servers do when a client
> simply ignores HelloRequest--a behaviour that has been allowed by all
> existing TLS specs for 10 years?

I always wondered how this behavior was supposed to work. For gnutls an
error is returned if the request is ignored.  I think the use cases of
these packets for renegotiation should be clearly defined (i.e. why send
this packets and what should be expected from peer). I don't know how
easy it is to implement the semantics precisely, but so far I didn't see
any compelling reason to do so.

regards,
Nikos