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From: "Pascal J. Bourguignon" <pjb@informatimago.com>
Newsgroups: comp.lang.ada
Subject: Re: Side-channel Attacks (Time)
Date: Fri, 25 Apr 2014 07:09:24 +0200
Organization: Informatimago
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Xref: news.eternal-september.org comp.lang.ada:19583
Date: 2014-04-25T07:09:24+02:00
List-Id: <comp.lang.ada>

Shark8 <OneWingedShark@gmail.com> writes:

> Considering the needs for a secure, verified security library [to
> replace OpenSSL] I was wondering about using the TASK construct in
> conjunction with DELAY UNTIL /OP_UPPERBOUND/* would be an acceptable
> countermeasure.

It could help. 

Choosing an algorithm without branches, and with fixed count loops would
be better.

But even in that case, if physical access to the processor is available,
physical side effects can be detected, and from them information about
the data can be deduced.

Of course, it's as always a matter of risk and graduated counter-measures.

-- 
__Pascal Bourguignon__
http://www.informatimago.com/
"Le mercure monte ?  C'est le moment d'acheter !"