Feeding /dev/random with /dev/urandom

From: erm67 (ermscag_at_tin.it)
Date: 04/28/04

  • Next message: Juha Laiho: "Re: Feeding /dev/random with /dev/urandom" 
    Date: 28 Apr 2004 08:25:31 -0700

    The latest linux kernel features a blocking /dev/random device, that
    is it will block when the available entropy is not sufficient. I found
    that some motherboards has a hw randomness generator and that it can
    be used, with rngd from http://sourceforge.net/projects/gkernel/ to
    feed /dev/random so that its entropy pools are always ready.
    My motherboard doesn't have this device and besides is very slow thus
    /dev/random often blocks.
    The 'solution' I found is to instruct rngd to read from /dev/urandom
    (non blocking) and to feed /dev/random.
    Of course this seems quite silly even to me :-) but now
    /proc/sys/kernel/random/entropy_avail always reports that entropy is
    available and all apps reading /dev/random no longer blocks.
    The question the random number from /dev/random are still 'good' is
    using this method?

  • Next message: Juha Laiho: "Re: Feeding /dev/random with /dev/urandom"

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