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SubjectRe: [PATCH][RFC] Allow net devices to contribute to /dev/random
Hi!

> > Here is my reasoning. I'd like to quote drivers/char/random.c:
> > * add_interrupt_randomness() uses the inter-interrupt timing as random
> > * inputs to the entropy pool. Note that not all interrupts are good
> > * sources of randomness! For example, the timer interrupts is not a
> > * good choice, because the periodicity of the interrupts is too
> > * regular, and hence predictable to an attacker. Disk interrupts are
> > * a better measure, since the timing of the disk interrupts are more
> > * unpredictable.
> > *
> > * All of these routines try to estimate how many bits of randomness a
> > * particular randomness source. They do this by keeping track of the
> > * first and second order deltas of the event timings.
>
> Obviously the timer interrupt would be the worst idea ever. Its the
> same value (HZ) on almost all versions of Linux (Alpha being on example
> where it is not the same).

Actually, not quite. On 2.4.9 system, console kept interrupts disabled
for so long that timer interrupt was pretty good source of randomness.

Pavel
--
I'm pavel@ucw.cz. "In my country we have almost anarchy and I don't care."
Panos Katsaloulis describing me w.r.t. patents at discuss@linmodems.org
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