[guardian-dev] CacheWord Key Derivation

[Michael Rogers]

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On 18/03/14 11:13, Abel Luck wrote:
> This looks super Michael, thanks for sharing. We very well might
> adapt it for our needs.

That's great!

> Have you tested it across a spread of devices? Does it produce
> strong iteration counts?

I've tested across four devices: Huawei U8110, Arnova GBook, Sony
Xperia Tipo and Galaxy Nexus... a bottom-heavy sample. I also have
some data from more modern devices that I haven't examined yet.

The iteration counts are generally sane on the devices I've tested,
but they do depend on how much work the device is doing when the
calibration happens. Perhaps it would make sense to do a
mini-calibration at each startup, compile the statistics over time,
and re-encrypt with a new iteration count if the initial calibration
was way off.

Cheers,
Michael

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