3 # Copyright (c) 2001-2006,2012 Douglas Barton, dougb@FreeBSD.org
6 # Redistribution and use in source and binary forms, with or without
7 # modification, are permitted provided that the following conditions
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.
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
29 # This script is called by cron to store bits of randomness which are
30 # then used to seed /dev/random on boot.
32 # Originally developed by Doug Barton, dougb@FreeBSD.org
36 # If there is a global system configuration file, suck it in.
38 if [ -r /etc/defaults/rc.conf ]; then
39 . /etc/defaults/rc.conf
40 source_rc_confs 2>/dev/null
41 elif [ -r /etc/rc.conf ]; then
42 . /etc/rc.conf 2>/dev/null
45 case ${entropy_dir} in
50 entropy_dir=${entropy_dir:-/var/db/entropy}
54 entropy_save_sz=${entropy_save_sz:-2048}
55 entropy_save_num=${entropy_save_num:-8}
57 if [ ! -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 \
64 cd "${entropy_dir}" || {
65 logger -is -t "$0" Cannot cd to the entropy directory: "${entropy_dir}". \
66 Entropy file rotation is aborted.; exit 1; }
68 for 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 ${f}
75 n=$(( ${entropy_save_num} - 1 ))
76 while [ ${n} -ge 1 ]; do
77 if [ -f "saved-entropy.${n}" ]; then
78 mv "saved-entropy.${n}" "saved-entropy.$(( ${n} + 1 ))"
79 elif [ -e "saved-entropy.${n}" -o -L "saved-entropy.${n}" ]; then
81 "${entropy_dir}/saved-entropy.${n}" is not a regular file, and so \
82 it will not be rotated. Entropy file rotation is aborted.
88 dd if=/dev/random of=saved-entropy.1 bs=${entropy_save_sz} count=1 2>/dev/null