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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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