Re: [TLS] Data volume limits

Russ Housley <housley@vigilsec.com> Tue, 15 December 2015 22:18 UTC

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From: Russ Housley <housley@vigilsec.com>
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Date: Tue, 15 Dec 2015 17:18:35 -0500
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To: Eric Rescorla <ekr@rtfm.com>
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Subject: Re: [TLS] Data volume limits
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On Dec 15, 2015, at 4:14 PM, Eric Rescorla wrote:

> Watson kindly prepared some text that described the limits on what's safe
> for AES-GCM and restricting all algorithms with TLS 1.3 to that lower
> limit (2^{36} bytes), even though ChaCha doesn't have the same
> restriction.
> 
> I wanted to get people's opinions on whether that's actually what we want
> or whether we should (as is my instinct) allow people to use ChaCha
> for longer periods.

Perhaps the algorithm registration can provide the limit, allowing implementations use the full period for each algorithm.

Russ