Re: [TLS] Data volume limits

Florian Weimer <fweimer@redhat.com> Mon, 04 January 2016 12:22 UTC

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To: Hubert Kario <hkario@redhat.com>
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From: Florian Weimer <fweimer@redhat.com>
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Subject: Re: [TLS] Data volume limits
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On 01/04/2016 01:19 PM, Hubert Kario wrote:

>> Dealing with this during the initial handshake is fine.  But
>> supporting direction-switching after that is *really* difficult.
> 
> yes, this is a bit more problematic, especially for one-sided transfers. 
> For example, when one side is just sending a multi-gigabyte transfer as 
> a reply to a single command - there may be megabytes transferred before 
> the other side reads our request for rekey and then our "CCS" message

Yes, this is the issue I meant.  I simply don't see a way to re-inject
new randomness without a round-trip.  (Key update without new randomness
doesn't face this challenge, but then it's mostly cheating.)

Florian