Re: [PATCH v3 3/4] crypto: exynos - Reseed PRNG after generating 2^16 random bytes

[Krzysztof Kozlowski]

On Tue, Dec 12, 2017 at 5:36 PM, Åukasz Stelmach <l.stelmach@xxxxxxxxxxx> wrote:
> Reseed PRNG after reading 65 kB of randomness. Although this may reduce
> performance, in most cases the loss is not noticeable. Also the time
> based threshold for reseeding is changed to one second. Reseeding is
> performed whenever either limit is exceeded.
>
> Reseeding of a PRNG does not increase entropy, but it helps preventing
> backtracking the internal state of the device from its output sequence,
> and hence, prevents potential attacker from predicting numbers to be
> generated.
>
> Signed-off-by: Åukasz Stelmach <l.stelmach@xxxxxxxxxxx>
> Reviewed-by: Stephan Mueller <smueller@xxxxxxxxxx>
> ---
>  drivers/crypto/exynos-rng.c | 15 +++++++++++----
>  1 file changed, 11 insertions(+), 4 deletions(-)
>

Reviewed-by: Krzysztof Kozlowski <krzk@xxxxxxxxxx>

Best regards,
Krzysztof