openrc/init.d/urandom

#!/sbin/runscript
# Copyright 2007-2008 Roy Marples <roy@marples.name>
# All rights reserved. Released under the 2-clause BSD license.

urandom_seed=${urandom_seed:-${URANDOM_SEED:-/var/run/random-seed}}

description="Initializes the random number generator."

depend()
{
	need localmount
	keyword nojail
}

save_seed()
{
	local psz=1

	if [ -e /proc/sys/kernel/random/poolsize ]; then
		psz=$(($(cat /proc/sys/kernel/random/poolsize) / 4096))
	fi

	(	# sub shell to prevent umask pollution
		umask 077
		dd if=/dev/urandom of="${urandom_seed}" count=${psz} 2>/dev/null
	)
}

start()
{
	[ -c /dev/urandom ] || return
	if [ -f "${urandom_seed}" ]; then
		ebegin "Initializing random number generator"
		cat "${urandom_seed}" > /dev/urandom
		eend $? "Error initializing random number generator"
	fi
	rm -f "${urandom_seed}" && save_seed
	return 0
}

stop()
{
	ebegin "Saving random seed"
	save_seed
	eend $? "Failed to save random seed"
}