usr.sbin/bsdinstall/scripts/hardening

   1 #!/bin/sh
   2 #-
   3 # Copyright (c) 2016 Bartek Rutkowski
   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 : ${DIALOG_OK=0}
  30
  31 echo -n > $BSDINSTALL_TMPETC/rc.conf.hardening
  32 echo -n > $BSDINSTALL_TMPETC/sysctl.conf.hardening
  33
  34 exec 3>&1
  35 FEATURES=$( dialog --backtitle "FreeBSD Installer" \
  36     --title "System Hardening" --nocancel --notags --separate-output \
  37     --checklist "Choose system security hardening options:" \
  38     0 0 0 \
  39         "hide_uids" "Hide processes running as other users" ${hide_uids:-off} \
  40         "hide_gids" "Hide processes running as other groups" ${hide_gids:-off} \
  41         "read_msgbuf" "Disable reading kernel message buffer for unprivileged users" ${read_msgbuf:-off} \
  42         "proc_debug" "Disable process debugging facilities for unprivileged users" ${proc_debug:-off} \
  43         "random_pid" "Randomize the PID of newly created processes" ${random_pid:-off} \
  44         "stack_guard" "Insert stack guard page ahead of the growable segments" ${stack_guard:-off} \
  45         "clear_tmp" "Clean the /tmp filesystem on system startup" ${clear_tmp:-off} \
  46         "disable_syslogd" "Disable opening Syslogd network socket (disables remote logging)" ${disable_syslogd:-off} \
  47         "disable_sendmail" "Disable Sendmail service" ${disable_sendmail:-off} \
  48 2>&1 1>&3 )
  49 exec 3>&-
  50
  51 for feature in $FEATURES; do
  52         if [ "$feature" = "hide_uids" ]; then
  53                 echo security.bsd.see_other_uids=0 >> $BSDINSTALL_TMPETC/sysctl.conf.hardening
  54         fi
  55         if [ "$feature" = "hide_gids" ]; then
  56                 echo security.bsd.see_other_gids=0 >> $BSDINSTALL_TMPETC/sysctl.conf.hardening
  57         fi
  58         if [ "$feature" = "read_msgbuf" ]; then
  59                 echo security.bsd.unprivileged_read_msgbuf=0 >> $BSDINSTALL_TMPETC/sysctl.conf.hardening
  60         fi
  61         if [ "$feature" = "proc_debug" ]; then
  62                 echo security.bsd.unprivileged_proc_debug=0 >> $BSDINSTALL_TMPETC/sysctl.conf.hardening
  63         fi
  64         if [ "$feature" = "random_pid" ]; then
  65                 echo kern.randompid=$(jot -r 1 9999) >> $BSDINSTALL_TMPETC/sysctl.conf.hardening
  66         fi
  67         if [ "$feature" = "stack_guard" ]; then
  68                 echo security.bsd.stack_guard_page=1 >> $BSDINSTALL_TMPETC/sysctl.conf.hardening
  69         fi
  70         if [ "$feature" = "clear_tmp" ]; then
  71                 echo 'clear_tmp_enable="YES"' >> $BSDINSTALL_TMPETC/rc.conf.hardening
  72         fi
  73         if [ "$feature" = "disable_syslogd" ]; then
  74                 echo 'syslogd_flags="-ss"' >> $BSDINSTALL_TMPETC/rc.conf.hardening
  75         fi
  76         if [ "$feature" = "disable_sendmail" ]; then
  77                 echo 'sendmail_enable="NONE"' >> $BSDINSTALL_TMPETC/rc.conf.hardening
  78         fi
  79 done
  80