openwrt/target/default/target_skeleton/etc/init.d/S20urandom

   1 #! /bin/sh
   2 #
   3 # urandom       This script saves the random seed between reboots.
   4 #               It is called from the boot, halt and reboot scripts.
   5 #
   6 # Version:      @(#)urandom  1.33  22-Jun-1998  miquels@cistron.nl
   7 #
   8
   9 [ -c /dev/urandom ] || exit 0
  10 #. /etc/default/rcS
  11
  12 case "$1" in
  13         start|"")
  14                 if [ "$VERBOSE" != no ]
  15                 then
  16                         echo -n "Initializing random number generator... "
  17                 fi
  18                 # Load and then save 512 bytes,
  19                 # which is the size of the entropy pool
  20                 if [ -f /etc/random-seed ]
  21                 then
  22                         cat /etc/random-seed >/dev/urandom
  23                 fi
  24                 rm -f /etc/random-seed
  25                 umask 077
  26                 dd if=/dev/urandom of=/etc/random-seed count=1 \
  27                         >/dev/null 2>&1 || echo "urandom start: failed."
  28                 umask 022
  29                 [ "$VERBOSE" != no ] && echo "done."
  30                 ;;
  31         stop)
  32                 # Carry a random seed from shut-down to start-up;
  33                 # see documentation in linux/drivers/char/random.c
  34                 [ "$VERBOSE" != no ] && echo -n "Saving random seed... "
  35                 umask 077
  36                 dd if=/dev/urandom of=/etc/random-seed count=1 \
  37                         >/dev/null 2>&1 || echo "urandom stop: failed."
  38                 [ "$VERBOSE" != no ] && echo "done."
  39                 ;;
  40         *)
  41                 echo "Usage: urandom {start|stop}" >&2
  42                 exit 1
  43                 ;;
  44 esac