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Re: [TLS] PR for anti-downgrade mechanism

Christian Huitema <huitema@microsoft.com> Tue, 10 November 2015 00:30 UTC

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From: Christian Huitema <huitema@microsoft.com>
To: Eric Rescorla <ekr@rtfm.com>, Martin Thomson <martin.thomson@gmail.com>
Thread-Topic: [TLS] PR for anti-downgrade mechanism
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Subject: Re: [TLS] PR for anti-downgrade mechanism
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On Monday, November 9, 2015 3:53 PM, Eric Rescorla wrote:
> In an attempt to close the loop here, I've pushed a new PR version with a 64-bit sentinel with 
> the final byte being 00 for TLS 1.2 and 01 for TLS 1.3. If anyone strongly objects to this
> construction, please raise your hand now.
>
> Otherwise, I plan to merge this on Wednesday.
> 
> https://github.com/tlswg/tls13-spec/pull/284

Editorial: your proposed text says "...MUST set the first six  bytes of its Random value to the the bytes 44 4F 57 4E 47 52 44 01." I assume you mean the first 8 bytes, and that you do not really want to have "the" twice. 

Could you also add a reference to the document that specifies using 44 4F  57 4E 47 52 44 00 by "TLS 1.2 servers which are  negotiating TLS 1.1 or below" ?

-- Christian Huitema

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