Re: [TLS] draft-mcgrew-aead-aes-cbc-hmac-sha2 can't be used as TLS 1.2 AEAD ciphers

Dr Stephen Henson <lists@drh-consultancy.co.uk> Mon, 09 September 2013 01:17 UTC

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Date: Mon, 09 Sep 2013 02:17:20 +0100
From: Dr Stephen Henson <lists@drh-consultancy.co.uk>
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Subject: Re: [TLS] draft-mcgrew-aead-aes-cbc-hmac-sha2 can't be used as TLS 1.2 AEAD ciphers
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On 28/08/2013 15:59, John Foley wrote:
> 
> CTS is a great idea.  This looks like it could be used to solve the
> problem.  We could certainly go this route.  However, thinking through
> the implementation details, is CTS widely deployed?  I'm fairly certain
> OpenSSL doesn't support CTS.  

It has support for mode operations for CTS in crypto/modes/cts128.c in
development versions of OpenSSL: that's almost all of the implementation. Those
can be readily converted to EVP which could be utilised in any new cipher suites.

Steve.
-- 
Dr Stephen N. Henson.
Core developer of the   OpenSSL project: http://www.openssl.org/
Freelance consultant see: http://www.drh-consultancy.co.uk/
Email: shenson@drh-consultancy.co.uk, PGP key: via homepage.