1#!/bin/sh 2# 3# Copyright (c) 2001-2006,2012 Douglas Barton, dougb@FreeBSD.org 4# All rights reserved. 5# 6# Redistribution and use in source and binary forms, with or without 7# modification, are permitted provided that the following conditions 8# are met: 9# 1. Redistributions of source code must retain the above copyright 10# notice, this list of conditions and the following disclaimer. 11# 2. Redistributions in binary form must reproduce the above copyright 12# notice, this list of conditions and the following disclaimer in the 13# documentation and/or other materials provided with the distribution. 14# 15# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18# ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25# SUCH DAMAGE. 26# 27# $FreeBSD$ 28 29# This script is called by cron to store bits of randomness which are 30# then used to seed /dev/random on boot. 31 32# Originally developed by Doug Barton, dougb@FreeBSD.org 33 34PATH=/bin:/usr/bin 35 36# If there is a global system configuration file, suck it in. 37# 38if [ -r /etc/defaults/rc.conf ]; then 39 . /etc/defaults/rc.conf 40 source_rc_confs 2>/dev/null 41elif [ -r /etc/rc.conf ]; then 42 . /etc/rc.conf 2>/dev/null 43fi 44 45case ${entropy_dir} in 46[Nn][Oo]) 47 exit 0 48 ;; 49*) 50 entropy_dir=${entropy_dir:-/var/db/entropy} 51 ;; 52esac 53 54entropy_save_sz=${entropy_save_sz:-2048} 55entropy_save_num=${entropy_save_num:-8} 56 57if [ ! -d "${entropy_dir}" ]; then 58 install -d -o operator -g operator -m 0700 "${entropy_dir}" || { 59 logger -is -t "$0" The entropy directory "${entropy_dir}" does \ 60 not exist, and cannot be created. Therefore no entropy can \ 61 be saved.; exit 1; } 62fi 63 64cd "${entropy_dir}" || { 65 logger -is -t "$0" Cannot cd to the entropy directory: "${entropy_dir}". \ 66 Entropy file rotation is aborted.; exit 1; } 67 68for f in saved-entropy.*; do 69 case "${f}" in saved-entropy.\*) continue ;; esac # No files match 70 [ ${f#saved-entropy\.} -ge ${entropy_save_num} ] && unlink ${f} 71done 72 73umask 377 74 75n=$(( ${entropy_save_num} - 1 )) 76while [ ${n} -ge 1 ]; do 77 if [ -f "saved-entropy.${n}" ]; then 78 mv "saved-entropy.${n}" "saved-entropy.$(( ${n} + 1 ))" 79 elif [ -e "saved-entropy.${n}" -o -L "saved-entropy.${n}" ]; then 80 logger -is -t "$0" \ 81 "${entropy_dir}/saved-entropy.${n}" is not a regular file, and so \ 82 it will not be rotated. Entropy file rotation is aborted. 83 exit 1 84 fi 85 n=$(( ${n} - 1 )) 86done 87 88dd if=/dev/random of=saved-entropy.1 bs=${entropy_save_sz} count=1 2>/dev/null 89 90exit 0 91