Re: [TLS] Security review of TLS1.3 0-RTT

Derrell Piper <ddp@electric-loft.org> Thu, 04 May 2017 22:04 UTC

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From: Derrell Piper <ddp@electric-loft.org>
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Date: Thu, 04 May 2017 16:04:26 -0600
Cc: Eric Roscorla <ekr@rtfm.com>, "tls@ietf.org" <tls@ietf.org>
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To: Erik Nygren <erik+ietf@nygren.org>
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Subject: Re: [TLS] Security review of TLS1.3 0-RTT
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Sure, those are fine weasel words.  But do we really want to allow into this protocol something that can be misused with security implications in a protocol that’s attempting to solve a security problem?  I really don’t know.  I’m inclined to say, ‘no’ though.  For all those same reasons that IPsec provides replay detection, I think TLS should too.

Derrell

> On May 4, 2017, at 4:00 PM, Erik Nygren <erik+ietf@nygren.org> wrote:
> 
> "The onus is on clients not to send messages in 0-RTT data which are not safe to have replayed and which they would not be willing to retry across multiple 1-RTT connections. The onus is on servers to protect themselves against attacks employing 0-RTT data replication."
> 
> The server responsibility is a general property TLS can maintain while the client responsibility requires an application profile to define.