Re: [TLS] Comments/Questions on draft-gutmann-tls-encrypt-then-mac-00.txt

Peter Gutmann <pgut001@cs.auckland.ac.nz> Thu, 26 September 2013 04:54 UTC

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From: Peter Gutmann <pgut001@cs.auckland.ac.nz>
To: "<tls@ietf.org>" <tls@ietf.org>
Thread-Topic: [TLS] Comments/Questions on draft-gutmann-tls-encrypt-then-mac-00.txt
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Date: Thu, 26 Sep 2013 04:54:37 +0000
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Subject: Re: [TLS] Comments/Questions on draft-gutmann-tls-encrypt-then-mac-00.txt
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Martin Rex <mrex@sap.com> writes:
					 
>When changing from mac-pad-encrypt to encrypt-mac, as suggested
>by Peter's draft, the MAC no longer operates on the TLSComressed 
>PDU, but on the TLSCiphertext PDU -- which results in:
>
>       HMAC_hash(MAC_write_secret, seq_num + TLSCiphertext.type +
>                     TLSCiphertext.version + TLSCiphertext.length +
>                     TLSCiphertext.fragment));

So all that's necessary is to change the text to reflect this, and
perhaps a note to point it out?  That's fairly simple to do.

Peter.