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<div class="moz-cite-prefix">On 8/16/19 5:44 AM, Dr Paul Dale wrote:<br>
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cite="mid:D1D0E1FB-A6E9-4CAA-B810-82D2DAEED884@oracle.com">
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I investigated HAVEGE fairly deeply a couple of years ago. I am
completely in agreement with the basis of this source, however the
sticking point was the “expansion” phase. Essentially, every bit
of entropy gathered is turned into (just under) thirty two bits of
“entropy”. This is logically and physically impossible. As a
source, it appears reasonable to the usual tests (i.e. dieharder),
although <a href="https://en.wikipedia.org/wiki/TestU01" class=""
moz-do-not-send="true">TestU01</a> does pick up on it being less
than ideal.
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<div class="">I would, however, recommend Stephan Müller's <a
href="https://www.chronox.de/jent/doc/CPU-Jitter-NPTRNG.html"
class="" moz-do-not-send="true">CPU Jitter</a>. The gathering
is well researched and performed, no hidden tricks are present
and the bits produces are equiprobable.<br class="">
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Thanks. I will take a look at CPU Jitter. Entropy can be an issue
on some of my armv7 boards. I run CentOS on them, so all I need to
find are rpms for something to test it out...<br>
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cite="mid:D1D0E1FB-A6E9-4CAA-B810-82D2DAEED884@oracle.com">
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<div class="">Pauli</div>
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<div style="caret-color: rgb(0, 0, 0); color: rgb(0, 0,
0); font-family: Helvetica; font-size: 12px;
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none;">-- <br class="">
Dr Paul Dale | Distinguished Architect | Cryptographic
Foundations <br class="">
Phone +61 7 3031 7217<br class="">
Oracle Australia</div>
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<div class="">On 16 Aug 2019, at 7:31 pm, Robert
Moskowitz <<a href="mailto:rgm@htt-consult.com"
class="" moz-do-not-send="true">rgm@htt-consult.com</a>>
wrote:</div>
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<div class="moz-cite-prefix">On 8/16/19 5:26 AM,
Chitrang Srivastava wrote:<br class="">
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cite="mid:CANPP3o0WJtxh7ZDoBq=SD=sr0w+ix9zWv2y+e-UB5w0msHNrmQ@mail.gmail.com"
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<div dir="ltr" class="">Hi,<br class="">
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<div class="">I am working on an embedded
platform and now ported openssl 1.1.1b</div>
<div class="">TLS 1.2/1.3 is working fine.</div>
<div class="">While analysing random number ,
Rand pool initialization calls where I am
returning like this , </div>
<div class="">size_t <b class="">rand_pool_acquire_entropy</b>(RAND_POOL
*pool)<br class="">
{<br class="">
return
rand_pool_entropy_available(pool);<br class="">
} <br class="">
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<div class="">As noticed that <b class="">rand_unix.c</b>
has an implementation wcih samples 2 bits of
RTC, would that give enough entropy or any
other recommendation to have enough entropy
for embedded platforms?<br class="">
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Check out: <a class="moz-txt-link-freetext"
href="https://issihosts.com/haveged"
moz-do-not-send="true">https://issihosts.com/haveged</a><br
class="">
<br class="">
I talk about it here: <a
class="moz-txt-link-freetext"
href="http://www.htt-consult.com/CentOS7-armv7.html#RANDOMNESS"
moz-do-not-send="true">http://www.htt-consult.com/CentOS7-armv7.html#RANDOMNESS</a><br
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