RANDOMSOUND(8) System Manager's Manual RANDOMSOUND(8)NAME
randomsound - ALSA sound card related entropy gathering daemon.
SYNOPSIS
randomsound [options]
DESCRIPTION
Using the low order bit of the ADC output of your sound card, randomsound gathers entropy, debiases it and offers it up to your kernel's
random pool. It can be tweaked to only write into the pool when it drops below a certain level, and to back off once the pool is full
enough. This build will set your sound card into 16 bit mono unsigned input at 8KHz. If your sound card cannot do that then you will need
to change the defines in asoundrunner.c and recompile the package. You must have set up asound as root on your machine. This can be done
with the asoundconf tool and its set-default-card command.
You may also need to use the alsamixer to ensure that the sound card is generating plenty of noise. Set all the gains nice and high, turn
on any boosters you have. If you have a V_REFLVL or similar then consider tweaking that.
OPTIONS -D Daemonize
-v Increase verbosity. Can be used more than once.
-m specify minimum number of bits of entropy in the pool.
-M specify max number of bits in the pool.
-b specify number of bytes of randomness to buffer for use.
-d specify number of bytes to deposit into the pool each time.
-h display help message
-V display version information.
AUTHOR
randomsound was written by Daniel Silverstone <dsilvers@digital-scurf.org>
Pepperfish August 18, 2007 RANDOMSOUND(8)
Check Out this Related Man Page
RNGD(8) System Manager's Manual RNGD(8)NAME
rngd - Check and feed random data from hardware device to kernel random device
SYNOPSIS
rngd [-b, --background] [-f, --foreground] [-i, --ignorefail] [-o, --random-device=file] [-p, --pid-file=file] [-r, --rng-device=file] [-s,
--random-step=nnn] [-W, --fill-watermark=nnn] [-d, --no-drng=1|0] [-n, --no-tpm=1|0] [-q, --quiet] [-v, --verbose] [-?, --help] [-V, --ver-
sion]
DESCRIPTION
This daemon feeds data from a random number generator to the kernel's random number entropy pool, after first checking the data to ensure
that it is properly random.
The -f or --foreground options can be used to tell rngd to avoid forking on startup. This is typically used for debugging. The -b or
--background options, which fork and put rngd into the background automatically, are the default.
The -r or --rng-device options can be used to select an alternate source of input, besides the default /dev/hwrandom. The -o or --random-
device options can be used to select an alternate entropy output device, besides the default /dev/random. Note that this device must sup-
port the Linux kernel /dev/random ioctl API.
FIXME: document random-step and timeout
OPTIONS -b, --background
Become a daemon (default)
-f, --foreground
Do not fork and become a daemon
-p file, --pid-file=file
File used for recording daemon PID, and multiple exclusion (default: /var/run/rngd.pid)
-i, --ignorefail
Ignore repeated fips failures
-o file, --random-device=file
Kernel device used for random number output (default: /dev/random)
-r file, --rng-device=file
Kernel device used for random number input (default: /dev/hwrandom)
-s nnn, --random-step=nnn
Number of bytes written to random-device at a time (default: 64)
-W n, --fill-watermark=nnn
Once we start doing it, feed entropy to random-device until at least fill-watermark bits of entropy are available in its entropy
pool (default: 2048). Setting this too high will cause rngd to dominate the contents of the entropy pool. Low values will hurt
system performance during entropy starves. Do not set fill-watermark above the size of the entropy pool (usually 4096 bits).
-d 1|0, --no-drng=1|0
Do not use drng as a source of random number input (default:0)
-n 1|0, --no-tpm=1|0
Do not use tpm as a source of random number input (default:0)
-q, --quiet
Suppress error messages
-v, --verbose
Report available entropy sources
-?, --help
Give a short summary of all program options.
-V, --version
Print program version
AUTHORS
Philipp Rumpf
Jeff Garzik - jgarzik@pobox.com
Matt Sottek
Brad Hill
rng-tools 4 March 2001 RNGD(8)