Add new System Hardening menu and options to bsdinstall.

This patch add new 'hardening' file responsible for new bsdinstall
'System Hardening' menu allowing users to set some sane and carefully
picked system security options (like random process id's, hiding
other users/groups processes and others).

All options are OFF by default in this patch due to POLA principle
with intention to turn change some of them to ON by default in future.

Reviewed by:	adrian, allanjude, bdrewery, nwhitehorn
Approved by:	adrian, allanjude
MFC after:	7 days

usr.sbin/bsdinstall/scripts/Makefile

@@ -1,6 +1,6 @@
 # $FreeBSD$
 
-SCRIPTS= auto adduser checksum config docsinstall entropy hostname jail \
+SCRIPTS= auto adduser checksum config docsinstall entropy hardening hostname jail \
 	 keymap mirrorselect mount netconfig netconfig_ipv4 netconfig_ipv6 \
 	 rootpass script services time umount wlanconfig zfsboot
 BINDIR= ${LIBEXECDIR}/bsdinstall

usr.sbin/bsdinstall/scripts/auto

@@ -385,6 +385,7 @@ if [ "$NETCONFIG_DONE" != yes ]; then
 fi
 bsdinstall time
 bsdinstall services
+bsdinstall hardening
 
 dialog --backtitle "FreeBSD Installer" --title "Add User Accounts" --yesno \
     "Would you like to add users to the installed system now?" 0 0 && \
@@ -401,6 +402,7 @@ finalconfig() {
 		"Hostname" "Set system hostname" \
 		"Network" "Networking configuration" \
 		"Services" "Set daemons to run on startup" \
+		"System Hardening" "Set security options" \
 		"Time Zone" "Set system timezone" \
 		"Handbook" "Install FreeBSD Handbook (requires network)" 2>&1 1>&3)
 	exec 3>&-
@@ -426,6 +428,10 @@ finalconfig() {
 		bsdinstall services
 		finalconfig
 		;;
+	"System Hardening")
+		bsdinstall hardening
+		finalconfig
+		;;
 	"Time Zone")
 		bsdinstall time
 		finalconfig

usr.sbin/bsdinstall/scripts/config

@@ -32,6 +32,9 @@
 cat $BSDINSTALL_TMPETC/rc.conf.* >> $BSDINSTALL_TMPETC/rc.conf
 rm $BSDINSTALL_TMPETC/rc.conf.*
 
+cat $BSDINSTALL_CHROOT/etc/sysctl.conf $BSDINSTALL_TMPETC/sysctl.conf.hardening >> $BSDINSTALL_TMPETC/sysctl.conf
+rm $BSDINSTALL_TMPETC/sysctl.conf.*
+
 cp $BSDINSTALL_TMPETC/* $BSDINSTALL_CHROOT/etc
 
 cat $BSDINSTALL_TMPBOOT/loader.conf.* >> $BSDINSTALL_TMPBOOT/loader.conf

usr.sbin/bsdinstall/scripts/hardening

@@ -0,0 +1,79 @@
+#!/bin/sh
+#-
+# Copyright (c) 2016 Bartek Rutkowski
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+# SUCH DAMAGE.
+#
+# $FreeBSD$
+
+: ${DIALOG_OK=0}
+
+echo -n > $BSDINSTALL_TMPETC/rc.conf.services
+
+exec 3>&1
+FEATURES=$( dialog --backtitle "FreeBSD Installer" \
+    --title "System Hardening" --nocancel --notags --separate-output \
+    --checklist "Choose system security hardening options:" \
+    0 0 0 \
+	"hide_uids" "Hide processes running as other users" ${hide_uids:-off} \
+	"hide_gids" "Hide processes running as other groups" ${hide_gids:-off} \
+	"read_msgbuf" "Disable reading kernel message buffer for unprivileged users" ${read_msgbuf:-off} \
+	"proc_debug" "Disable process debugging facilities for unprivileged users" ${proc_debug:-off} \
+	"random_pid" "Randomize the PID of newly created processes" ${random_id:-off} \
+	"stack_guard" "Insert stack guard page ahead of the growable segments" ${stack_guard:-off} \
+	"clear_tmp" "Clean the /tmp filesystem on system startup" ${clear_tmp:-off} \
+	"disable_syslogd" "Disable opening Syslogd network socket (disables remote logging)" ${disable_syslogd:-off} \
+	"disable_sendmail" "Disable Sendmail service" ${disable_sendmail:-off} \
+2>&1 1>&3 )
+exec 3>&-
+
+for feature in $FEATURES; do
+	if [ "$feature" = "hide_uids" ]; then
+		echo security.bsd.see_other_uids=0 >> $BSDINSTALL_TMPETC/sysctl.conf.hardening
+	fi
+	if [ "$feature" = "hide_gids" ]; then
+		echo security.bsd.see_other_gids=0 >> $BSDINSTALL_TMPETC/sysctl.conf.hardening
+	fi
+	if [ "$feature" = "read_msgbuf" ]; then
+		echo security.bsd.unprivileged_read_msgbuf=0 >> $BSDINSTALL_TMPETC/sysctl.conf.hardening
+	fi
+	if [ "$feature" = "proc_debug" ]; then
+		echo security.bsd.unprivileged_proc_debug=0 >> $BSDINSTALL_TMPETC/sysctl.conf.hardening
+	fi
+	if [ "$feature" = "random_id" ]; then
+		echo kern.randompid=$(jot -r 1 9999) >> $BSDINSTALL_TMPETC/sysctl.conf.hardening
+	fi
+	if [ "$feature" = "stack_guard" ]; then
+		echo security.bsd.stack_guard_page=1 >> $BSDINSTALL_TMPETC/sysctl.conf.hardening
+	fi
+	if [ "$feature" = "clear_tmp" ]; then
+		echo 'clear_tmp_enable="YES"' >> $BSDINSTALL_TMPETC/rc.conf.hardening
+	fi
+	if [ "$feature" = "disable_syslogd" ]; then
+		echo 'syslogd_flags="-ss"' >> $BSDINSTALL_TMPETC/rc.conf.hardening
+	fi
+	if [ "$feature" = "disable_sendmail" ]; then
+		echo 'sendmail_enable="NONE"' >> $BSDINSTALL_TMPETC/rc.conf.hardening
+	fi
+done
+