OpenSSLHowTo - CAcert Wiki

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http://pwet.fr/man/linux/fichiers_speciaux/random
google translation in english http://translate.google.fr/translate?u=http%3A%2F%2Fpwet.fr%2Fman%2Flinux%2Ffichiers_speciaux%2Frandom&hl=fr&ie=UTF-8&sl=fr&tl=en
random.c from /linux-2.6.26.5/drivers/char random.c
/dev/random
- it is useless to feed more than "poolsize" bit of data in /dev/random at a time.
- data put into /dev/random goes through a CRC32 pass before being put into the pool
- monitoring in /proc/sys/kernel/random
  - boot_id : random data fetched at boot time
  - uuid : random data for new disk devices ID (a new UUID for a new partition)
  - entropy_avail : instant size of entropy available (in bits)
  - poolsize : max size of the entropy pool (in bits)
  - read_wakeup_threshold : entropy threshold when processes waiting for entropy are waken up to fetch new random data (/dev/random only)
  - write_wakeup_threshold : entropy threshold under which the pool is feed with data ( cat randomdata > /dev/random )
entropy pool monitoring:

while sleep 1; do date; cat /proc/sys/kernel/random/entropy_avail ; done

    for i in 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 ; do 
      dieharder -d $i -g 63 ; 
    done