b163ba19de
Source /etc/default/urandom if present. This allows the rootfs to remain read-only while enabling the user to override the location of the random seed file. (From OE-Core rev: 415e1a4ac8120b28118671698459b098c965a4f6) Signed-off-by: Richard Tollerton <rich.tollerton@ni.com> Signed-off-by: Ben Shelton <ben.shelton@ni.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
1.4 KiB
Executable File
#!/bin/sh
BEGIN INIT INFO
Provides: urandom
Required-Start: $local_fs mountvirtfs
Required-Stop: $local_fs
Default-Start: S
Default-Stop: 0 6
Short-Description: Save and restore the random seed
Description: Save the random seed on shutdown and restore it on boot,
to ensure that the seed isn't predicable on startup
(because the boot process is predictable)
END INIT INFO
test -c /dev/urandom || exit 0
RANDOM_SEED_FILE=/var/lib/urandom/random-seed
. /etc/default/rcS [ -f /etc/default/urandom ] && . /etc/default/urandom
case "$1" in
start|"")
test "$VERBOSE" != no && echo "Initializing random number generator..."
# Load and then save 512 bytes, which is the size of the entropy
# pool. Also load the current date, in case the seed file is
# empty.
( date +%s.%N; [ -f "$RANDOM_SEED_FILE" ] && cat "$RANDOM_SEED_FILE" )
>/dev/urandom
rm -f "$RANDOM_SEED_FILE"
umask 077
dd if=/dev/urandom of=$RANDOM_SEED_FILE count=1
>/dev/null 2>&1 || echo "urandom start: failed."
umask 022
;;
stop)
# Carry a random seed from shut-down to start-up;
# see documentation in linux/drivers/char/random.c
test "$VERBOSE" != no && echo "Saving random seed..."
umask 077
dd if=/dev/urandom of=$RANDOM_SEED_FILE count=1
>/dev/null 2>&1 || echo "urandom stop: failed."
;;
*)
echo "Usage: urandom {start|stop}" >&2
exit 1
;;
esac
exit 0