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Re: [TLS] Clarifications and questions: TLS1.3 - Static RSA and AEAD

Jakob Breier <Jakob.Breier@rwth-aachen.de> Tue, 27 May 2014 14:52 UTC

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Date: Tue, 27 May 2014 16:51:47 +0200
From: Jakob Breier <Jakob.Breier@rwth-aachen.de>
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To: Dan Brown <dbrown@certicom.com>, "'tls@ietf.org'" <tls@ietf.org>
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Subject: Re: [TLS] Clarifications and questions: TLS1.3 - Static RSA and AEAD
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True :)
To just show the principle a simple example is more concise than the 
full blown HMAC_DRBG, though.

Regards,
Jakob Breier

On 05/27/2014 04:29 PM, Dan Brown wrote:
> Looks like PRNGs, e.g. HMAC_DRBG, being re-invented, by the way.
>
>> -----Original Message-----
>> From: TLS [mailto:tls-bounces@ietf.org] On Behalf Of Jakob Breier
>> Sent: Tuesday, May 27, 2014 10:18 AM
>> To: tls@ietf.org
>> Subject: Re: [TLS] Clarifications and questions: TLS1.3 - Static RSA and
> AEAD
>> On 05/27/2014 04:00 PM, Watson Ladd wrote:
>>>>> They will be in trouble. However, presumably if they have a place to
>>>>> store their private key, they can somehow store other random data
>>>>> there that they use to generate random values, no?
>>> But then they can store an incrementing counter for use with AES with
>>> a fixed key as a RNG. I don't see the problem here.
>> Even better, if there is some memory that can be securely erased, you
> could
>> retain PFS via something like
>> r_(j+1) = HMAC(longTermKey, r_j || counter ) where the cache of the
> current
>> random output r_j will be overwritten with r_(j+1).
>>
>> Regards,
>> Jakob Breier
>>
>> _______________________________________________
>> TLS mailing list
>> TLS@ietf.org
>> https://www.ietf.org/mailman/listinfo/tls

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