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  • Generate Random Data From Sound Card

    From OCTADE@news0@octade.net to sci.crypt on Tue Mar 3 05:16:47 2026
    From Newsgroup: sci.crypt

    Try one command to convert the sound card into a TRNG.

    It should work with the audio muted.

    arecord -D plughw -f S32_LE -t wav -c2 -r 44100 \
    | xxd -p -c 0 | fold -w 8 | cut -c 5-6 | tr -d '\n' \
    | fold -w 63 | head -n 320 | tail -n 20

    This harvests the low-order noise bits and discards the silent bits.

    The remainder is electronic noise from the sound card.

    The user may need to specify the sound card with:

    ```-D plughw:A,B```

    where A is the card number and B is the device number obtained via 'arecord -l'.
    --
    = OCTADE = alt.rhubarb = misc.misc = sci.crypt =
    = https://soc.octade.net/octade =

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  • From OCTADE@news0@octade.net to sci.crypt on Tue Mar 3 23:50:53 2026
    From Newsgroup: sci.crypt


    What would be a good, bash-based mechanism for identifying and testing the local sound cards and devices to find the ones that provide quality entropy?
    --
    = OCTADE = alt.rhubarb = misc.misc = sci.crypt =
    = https://soc.octade.net/octade =

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  • From Rich@rich@example.invalid to sci.crypt on Wed Mar 4 14:49:31 2026
    From Newsgroup: sci.crypt

    OCTADE <news0@octade.net> wrote:

    What would be a good, bash-based mechanism for identifying and
    testing the local sound cards and devices to find the ones that
    provide quality entropy?

    On Linux, with the ALSA drivers, the 'arecord' CLI tool can record from
    any sound card ALSA recognizes to a WAV file.

    Testing for 'quality entropy' is a very different thing however.
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  • From Chris M. Thomasson@chris.m.thomasson.1@gmail.com to sci.crypt on Wed Mar 4 14:25:05 2026
    From Newsgroup: sci.crypt

    On 3/4/2026 6:49 AM, Rich wrote:
    OCTADE <news0@octade.net> wrote:

    What would be a good, bash-based mechanism for identifying and
    testing the local sound cards and devices to find the ones that
    provide quality entropy?

    On Linux, with the ALSA drivers, the 'arecord' CLI tool can record from
    any sound card ALSA recognizes to a WAV file.

    Testing for 'quality entropy' is a very different thing however.

    Big time! Fwiw, side note, generating "random" data from threading race conditions:

    https://groups.google.com/g/comp.lang.c++/c/7u_rLgQe86k/m/fYU9SnuAFQAJ
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