#!/bin/mksh
# $MirSecuCron$
# $MirOS: src/etc/security,v 1.22 2009/10/17 16:20:04 tg Exp $
# $OpenBSD: security,v 1.71 2005/02/22 10:50:55 otto Exp $
# from: @(#)security	8.1 (Berkeley) 6/9/93

export TZ=UTC PATH=/bin:/usr/bin:/sbin:/usr/sbin RCSLOCALID='!MirSecuCron'
cd /
nl='
'

umask 077

function _diffhdr {
	print
	print ======
	print -r -- "$1 diffs (-OLD  +NEW)"
	print ======
}
function _stripcom {
	cat "$@" | { set -o noglob; while read _line; do
		_line=${_line%%#*}
		[[ -n $_line ]] && print -r -- $_line
	done; }
}
rm -f /var/backups/rcs.log

# fback [-m|-n] <file> [<backupfile>]
function fback {
	local fn bf cf
	local wd o fd fo ft fa fp

	if [[ $1 = -m ]]; then
		o=md5
		shift
	elif [[ $1 = -n ]]; then
		o=nodiff
		shift
	elif [[ $1 = -- ]]; then
		shift
	fi
	fn=$1
	cf=$fn
	bf=$2
	ft=$3
	[[ -s $fn ]] || return
	[[ -n $bf ]] || bf=$(sed 's/^\///;s/\//_/g' <<<"$fn")
	[[ -n $ft ]] || ft=$fn

	wd=$(pwd)
	cd /var/backups

	# migration for special cases
	if [[ $o = md5 ]]; then
		cf=$DIR/_md5
		md5 <"$fn" >$cf
		[[ -e "$bf".current.md5 ]] && \
		    mv "$bf".current.md5 "$bf".md5.current
		[[ -e "$bf".backup.md5 ]] && \
		    mv "$bf".backup.md5 "$bf".md5.backup
		bf=$bf.md5
	fi

	if [[ ! -x /usr/bin/co ]]; then
		# back things up without RCS tools
		if [[ ! -e $bf.current ]] || ! cmp -s "$cf" "$bf.current"; then
			[[ -e $bf.current ]] && \
			    cp -p "$bf.current" "$bf.backup"
			cp -p "$cf" "$bf.current"
			[[ $o = nodiff ]] || _diffhdr "$ft"
			[[ $o = nodiff ]] || if [[ -e $bf.backup ]]; then
				diff -up /var/backups/"$bf.backup" \
				    /var/backups/"$bf.current"
			else
				diff -u /dev/null /var/backups/"$bf.current"
			fi
			chown 0:0 "$bf.current"
			chmod 0600 "$bf.current"
		fi
		cd "$wd"
		return
	fi

	# migration for RCS/foo,x (-x,v/) to RCS/foo (-x)
	[[ -e RCS/$bf,v ]] && mv -f RCS/$bf,v RCS/$bf

	# migration for non-RCS to RCS schema
	if [[ -e $bf.backup ]]; then
		[[ -e RCS/$bf ]] && co -x -M -T -l "$bf" >>rcs.log 2>&1
		fd=$(stat -f '%Sm' -t '%Y/%m/%d %H:%M:%S' "$bf.backup")
		fo=$(stat -f '%Su' "$bf.backup")
		mv -f "$bf.backup" "$bf"
		ci -x -M -T -u -d"$fd" -t-"automatic backup for $fn" -w"$fo" \
		    -sAncient -f -m"legacy backup $fn" "$bf" >>rcs.log 2>&1
	fi
	if [[ -e $bf.current ]]; then
		[[ -e RCS/$bf ]] && co -x -M -T -l "$bf" >>rcs.log 2>&1
		fd=$(stat -f '%Sm' -t '%Y/%m/%d %H:%M:%S' "$bf.current")
		fo=$(stat -f '%Su' "$bf.current")
		mv -f "$bf.current" "$bf"
		ci -x -M -T -u -d"$fd" -t-"automatic backup for $fn" -w"$fo" \
		    -sLegacy -f -m"legacy current $fn" "$bf" >>rcs.log 2>&1
	fi
	rm -f "$bf.backup" "$bf.current"

	# back things up using RCS tools
	if [[ ! -e $bf ]] || ! cmp -s "$cf" "$bf"; then
		[[ -e RCS/$bf ]] && co -x -M -T -l "$bf" >>rcs.log 2>&1
		rm -f "$bf"
		cp -p "$cf" "$bf"
		fd=$(stat -f '%Sm' -t '%Y/%m/%d %H:%M:%S' "$fn")
		fo=$(stat -f '%Su' "$fn")
		fa=$(stat -f '%u:%g' "$fn")
		fp=$(stat -f '%Mp%Lp' "$fn")
		[[ $o = nodiff ]] || _diffhdr "$ft"
		[[ $o = nodiff ]] || if [[ -e RCS/$bf ]]; then
			rcsdiff -x -q -u -p /var/backups/"$bf"
		else
			diff -u /dev/null /var/backups/"$bf"
		fi
		ci -x -M -T -u -d"$fd" -t-"automatic backup for $fn" -w"$fo" \
		    -sBackup -m"$(date) backup for $fn" "$bf" >>rcs.log 2>&1
		cp -p "$bf" "$cf"
		chown 0:0 "$bf" "RCS/$bf"
		chmod 0400 "$bf" "RCS/$bf"
		chown $fa "$cf"
		chmod $fp "$cf"
	fi
	cd "$wd"
}

DIR=$(mktemp -d /tmp/_secure.XXXXXXXXXX) || exit 1
ERR=$DIR/_secure1
TMP1=$DIR/_secure2
TMP2=$DIR/_secure3
TMP3=$DIR/_secure4
LIST=$DIR/_secure5
OUTPUT=$DIR/_secure6

trap 'rm -rf $DIR; exit 1' 0 1 2 3 13 15

# Check the master password file syntax.
MP=/etc/master.passwd
awk -F: '{
	if ($0 ~ /^[	 ]*$/) {
		printf("Line %d is a blank line.\n", NR);
		next;
	}
	if (NF != 10)
		printf("Line %d has the wrong number of fields:\n%s\n", NR, $0);
	if ($1 ~ /^[+-]/)
		next;
	if ($1 == "")
		printf("Line %d has an empty login field:\n%s\n", NR, $0);
	else if ($1 !~ /^[A-Za-z0-9_][A-Za-z0-9_\-\.]*\$?$/)
		printf("Login %s has non-alphanumeric characters.\n", $1);
	if (length($1) > 31)
		printf("Login %s has more than 31 characters.\n", $1);
	if ($2 == "" && $1 !~ /^_*anoncvs$/ && $1 !~ /^_*rsync$/)
		printf("Login %s has no password.\n", $1);
	if ($2 != "" && length($2) != 13 && ($10 ~ /.*sh$/ || $10 == "") &&
	   ($2 !~ /^\$[0-9a-f]+\$/) && ($2 != "skey")) {
		if (system("test -s /etc/skey/"$1"") == 0)
			printf("Login %s is off but still has a valid shell and an entry in /etc/skey.\n", $1);
		if (system("test -d "$9" -a ! -r "$9"") == 0)
			printf("Login %s is off but still has valid shell and home directory is unreadable\n\t by root; cannot check for existence of alternate access files.\n", $1);
		else if (system("for file in .etc/ssh .rhosts .shosts .klogin; do if test -e "$9"/$file; then if ( (ls -ld "$9"/$file | cut -b 2-10 | grep -q r) && (test ! -O "$9"/$file)); then exit 1; fi; fi; done"))
			 printf("Login %s is off but still has a valid shell and alternate access files in\n\t home directory are still readable.\n",$1);
	}
	if ($3 == 0 && $1 != "root")
		printf("Login %s has a user ID of 0.\n", $1);
	if ($3 < 0)
		printf("Login %s has a negative user ID.\n", $1);
	if ($4 < 0)
		printf("Login %s has a negative group ID.\n", $1);
	if (int($7) != 0 && system("test "$7" -lt $(date +%s)") == 0)
		printf("Login %s has expired.\n", $1);
}' < $MP > $OUTPUT
if [ -s $OUTPUT ] ; then
	echo "\nChecking the ${MP} file:"
	cat $OUTPUT
fi

awk -F: '{ print $1 }' $MP | sort | uniq -d > $OUTPUT
if [ -s $OUTPUT ] ; then
	echo "\n${MP} has duplicate user names."
	column $OUTPUT
fi

awk -F: '/^[^\+]/ { print $1 " " $3 }' $MP | sort -n +1 | tee $TMP1 |
uniq -d -f 1 | awk '{ print $2 }' > $TMP2
set -A dupusers
if [ -s $TMP2 ] ; then
	echo "\n${MP} has duplicate user IDs."
	duptxt=
	while read uid; do
		grep " ${uid}\$" $TMP1 |&
		i=0
		while read -p uline; do
			duptxt=$duptxt$uline$nl
			if (( i++ )); then
				dupusers[${#dupusers[*]}]=-e
				dupusers[${#dupusers[*]}]='^'${uline%% *}' '
			fi
		done
	done <$TMP2
	print -nr -- "$duptxt" | column
fi
(( ${#dupusers[*]} )) || set -A dupusers -- -e '^$'

if [[ ! -d /var/backups/RCS/. ]]; then
	mkdir -p /var/backups/RCS
	chmod 700 /var/backups /var/backups/RCS
fi
for i in current backup; do
	f=/var/backups/master.passwd.$i
	[[ -e $f ]] && mv $f /var/backups/etc_master.passwd.$i
done

# Check the group file syntax.
GRP=/etc/group
awk -F: '{
	if ($0 ~ /^[	 ]*$/) {
		printf("Line %d is a blank line.\n", NR);
		next;
	}
	if ($1 ~ /^[+-].*$/)
		next;
	if (NF != 4)
		printf("Line %d has the wrong number of fields:\n%s\n", NR, $0);
	if ($1 !~ /^[A-Za-z0-9_][A-Za-z0-9_\-\.]*$/)
		printf("Group %s has non-alphanumeric characters.\n", $1);
	if (length($1) > 31)
		printf("Group %s has more than 31 characters.\n", $1);
	if ($3 !~ /[0-9]*/)
		printf("Login %s has a negative group ID.\n", $1);
}' < $GRP > $OUTPUT
if [ -s $OUTPUT ] ; then
	echo "\nChecking the ${GRP} file:"
	cat $OUTPUT
fi

awk -F: '{ print $1 }' $GRP | sort | uniq -d > $OUTPUT
if [ -s $OUTPUT ] ; then
	echo "\n${GRP} has duplicate group names."
	column $OUTPUT
fi

# Check for root paths, umask values in startup files.
# The check for the root paths is problematical -- it's likely to fail
# in other environments.  Once the shells have been modified to warn
# of '.' in the path, the path tests should go away.
> $OUTPUT
rhome=/
umaskset=no
list="/etc/profile ${rhome}/.profile"
for i in $list; do
	if [ -s $i ] ; then
		if egrep umask $i > /dev/null ; then
			umaskset=yes
		fi
		egrep umask $i |
		awk '$2 % 100 < 20 \
			{ print "Root umask is group writable" } \
		     $2 % 10 < 2 \
			{ print "Root umask is other writable" }' >> $OUTPUT
		SAVE_PATH=$PATH
		SAVE_ENV=$ENV
		unset PATH ENV
		mksh << end-of-sh > /dev/null 2>&1
			. $i
			if [ X"\$PATH" != "X" ]; then
				list=\`echo \$PATH | /usr/bin/sed -e 's/:/ /g'\`
				/bin/ls -ldgT \$list > $TMP1
			else
				> $TMP1
			fi
			echo \$ENV >> $TMP2
end-of-sh
		PATH=$SAVE_PATH
		ENV=$SAVE_ENV
		awk '{
			if ($10 ~ /^\.$/) {
				print "The root path includes .";
				next;
			}
		     }
		     $1 ~ /^d....w/ \
	{ print "Root path directory " $10 " is group writable." } \
		     $1 ~ /^d.......w/ \
	{ print "Root path directory " $10 " is other writable." }' \
		< $TMP1 >> $OUTPUT

	fi
done
if [ $umaskset = "no" -o -s $OUTPUT ] ; then
	echo "\nChecking root sh paths, umask values:\n${list}"
	if [ -s $OUTPUT ] ; then
		cat $OUTPUT
	fi
	if [ $umaskset = "no" ] ; then
		echo "\nRoot sh startup files do not set the umask."
	fi
fi

# Root and uucp should both be in /etc/ftpusers.
if egrep root /etc/ftpusers > /dev/null ; then
	:
else
	echo "\nRoot not listed in /etc/ftpusers file."
fi
if egrep uucp /etc/ftpusers > /dev/null ; then
	:
else
	echo "\nUucp not listed in /etc/ftpusers file."
fi

# Uudecode should not be in the /etc/mail/aliases file.
if egrep 'uudecode|decode' /etc/mail/aliases; then
	echo "\nThere is an entry for uudecode in the /etc/mail/aliases file."
fi

# Files that should not have + signs.
list="/etc/hosts.equiv /etc/shosts.equiv /etc/hosts.lpd"
for f in $list ; do
	if [ -s $f ] ; then
		awk '{
			if ($0 ~ /^\+@.*$/)
				next;
			if ($0 ~ /^\+.*$/)
				printf("\nPlus sign in %s file.\n", FILENAME);
		}' $f
	fi
done

# Check for special users with .rhosts/.shosts files.  Only root
# should have .rhosts/.shosts files.  Also, .rhosts/.shosts
# files should not have plus signs.
awk -F: '$1 != "root" && $1 !~ /^[+-]/ && \
	($3 < 100 || $1 == "ftp" || $1 == "uucp") \
		{ print $1 " " $6 }' /etc/passwd |
grep -v "${dupusers[@]}" |
while read uid homedir; do
	for j in .rhosts .shosts; do
		# Root owned .rhosts/.shosts files are ok.
		if [ -s ${homedir}/$j -a ! -O ${homedir}/$j ] ; then
			rhost=$(ls -ldgT ${homedir}/$j)
			echo "${uid}: ${rhost}"
		fi
	done
done > $OUTPUT
if [ -s $OUTPUT ] ; then
	echo "\nChecking for special users with .rhosts/.shosts files."
	cat $OUTPUT
fi

awk -F: '/^[^+-]/ { print $1 " " $6 }' /etc/passwd | \
grep -v "${dupusers[@]}" |
while read uid homedir; do
	for j in .rhosts .shosts; do
		if [ -s ${homedir}/$j ] ; then
			awk '{
				if ($0 ~ /^+@.*$/ )
					next;
				if ($0 ~ /^\+[ 	]*$/ )
					printf("%s has + sign in it.\n",
						FILENAME);
			}' ${homedir}/$j
		fi
	done
done > $OUTPUT
if [ -s $OUTPUT ] ; then
	echo "\nChecking .rhosts/.shosts files syntax."
	cat $OUTPUT
fi

# Check home directories.  Directories should not be owned by someone else
# or writeable.
awk -F: '/^[^+-]/ { print $1 " " $6 }' /etc/passwd | \
grep -v "${dupusers[@]}" |
while read uid homedir; do
	if [ -d ${homedir}/ ] ; then
		file=$(ls -ldgT ${homedir})
		echo "${uid} ${file}"
	fi
done |
awk '$1 != $4 && $4 != "root" \
	{ print "user " $1 " home directory is owned by " $4 }
     $2 ~ /^-....w/ \
	{ print "user " $1 " home directory is group writable" }
     $2 ~ /^-.......w/ \
	{ print "user " $1 " home directory is other writable" }' > $OUTPUT
if [ -s $OUTPUT ] ; then
	echo "\nChecking home directories."
	cat $OUTPUT
fi

# Files that should not be owned by someone else or readable.
list=".netrc .rhosts .gnupg/secring.gpg .gnupg/random_seed \
	.pgp/secring.pgp .shosts .etc/ssh/identity .etc/ssh/id_dsa .etc/ssh/id_rsa"
awk -F: '/^[^+-]/ { print $1 " " $6 }' /etc/passwd | \
grep -v "${dupusers[@]}" |
while read uid homedir; do
	for f in $list ; do
		file=${homedir}/${f}
		if [ -f $file ] ; then
			echo "${uid} ${f} $(ls -ldgT ${file})"
		fi
	done
done |
awk '$1 != $5 && $5 != "root" \
	{ print "user " $1 " " $2 " file is owned by " $5 }
     $3 ~ /^-...r/ \
	{ print "user " $1 " " $2 " file is group readable" }
     $3 ~ /^-......r/ \
	{ print "user " $1 " " $2 " file is other readable" }
     $3 ~ /^-....w/ \
	{ print "user " $1 " " $2 " file is group writable" }
     $3 ~ /^-.......w/ \
	{ print "user " $1 " " $2 " file is other writable" }' > $OUTPUT

# Files that should not be owned by someone else or writeable.
list=".bashrc .bash_profile .bash_login .bash_logout .cshrc \
      .emacs .exrc .forward .fvwmrc .inputrc .klogin .kshrc .login \
      .logout .nexrc .profile .screenrc .etc/ssh .etc/ssh/config \
      .etc/ssh/authorized_keys .etc/ssh/authorized_keys2 .etc/ssh/environment \
      .etc/ssh/known_hosts .etc/ssh/rc .tcshrc .twmrc .xsession .xinitrc \
      .Xdefaults .Xauthority mail"
awk -F: '/^[^+-]/ { print $1 " " $6 }' /etc/passwd | \
grep -v "${dupusers[@]}" |
while read uid homedir; do
	for f in $list ; do
		file=${homedir}/${f}
		if [ -f $file ] ; then
			echo "${uid} ${f} $(ls -ldgT ${file})"
		fi
	done
done |
awk '$1 != $5 && $5 != "root" \
	{ print "user " $1 " " $2 " file is owned by " $5 }
     $3 ~ /^-....w/ \
	{ print "user " $1 " " $2 " file is group writable" }
     $3 ~ /^-.......w/ \
	{ print "user " $1 " " $2 " file is other writable" }' >> $OUTPUT
if [ -s $OUTPUT ] ; then
	echo "\nChecking dot files."
	cat $OUTPUT
fi

# Mailboxes should be owned by user and unreadable.
ls -l /var/mail | sed 1d | \
awk '$3 != $9 \
	{ print "user " $9 " mailbox is owned by " $3 }
     $1 != "-rw-------" \
	{ print "user " $9 " mailbox is " $1 ", group " $4 }' > $OUTPUT
if [ -s $OUTPUT ] ; then
	echo "\nChecking mailbox ownership."
	cat $OUTPUT
fi

# File systems should not be globally exported.
if [ -s /etc/exports ] ; then
	awk '{
		if (($1 ~ /^#/) || ($1 ~ /^$/))
			next;
		readonly = 0;
		for (i = 2; i <= NF; ++i) {
			if ($i ~ /^-ro$/)
				readonly = 1;
			else if ($i !~ /^-/ || $i ~ /^-network/)
				next;
		}
		if (readonly)
			print "File system " $1 " globally exported, read-only."
		else
			print "File system " $1 " globally exported, read-write."
	}' < /etc/exports > $OUTPUT
	if [ -s $OUTPUT ] ; then
		echo "\nChecking for globally exported file systems."
		cat $OUTPUT
	fi
fi

# Display any changes in setuid/setgid files and devices.
pending="\nChecking setuid/setgid files and devices:\n"
(find / \( ! -fstype local -o -fstype fdesc -o -fstype kernfs \
	-o -fstype procfs \) -a -prune -o \
	-type f -a \( -perm -u+s -o -perm -g+s \) -print0 -o \
	! -type d -a ! -type f -a ! -type l -a ! -type s -a ! -type p \
	-print0 | xargs -0 ls -ldgT | sort +9 > $LIST) 2> $OUTPUT

# Display any errors that occurred during system file walk.
if [ -s $OUTPUT ] ; then
	echo "${pending}Setuid/device find errors:"
	pending=
	cat $OUTPUT
	echo ""
fi

# Display any changes in the setuid/setgid file list.
FIELDS1=1.1,1.2,1.3,1.4,1.5,1.6,1.7,1.8,1.9,0
FIELDS2=2.1,2.2,2.3,2.4,2.5,2.6,2.7,2.8,2.9,0
egrep -av '^[bc]' $LIST | join -o $FIELDS2 -110 -210 -v2 /dev/null - > $TMP1
if [ -s $TMP1 ] ; then
	# Check to make sure uudecode isn't setuid.
	if grep -aw uudecode $TMP1 > /dev/null ; then
		echo "${pending}\nUudecode is setuid."
		pending=
	fi

	CUR=/var/backups/setuid.current
	BACK=/var/backups/setuid.backup

	if [ -s $CUR ] ; then
		if cmp -s $CUR $TMP1 ; then
			:
		else
			> $TMP2
			join -o $FIELDS2 -110 -210 -v2 $CUR $TMP1 > $OUTPUT
			if [ -s $OUTPUT ] ; then
				echo "${pending}Setuid additions:"
				pending=
				tee -a $TMP2 < $OUTPUT | column -t
				echo ""
			fi

			join -o $FIELDS1 -110 -210 -v1 $CUR $TMP1 > $OUTPUT
			if [ -s $OUTPUT ] ; then
				echo "${pending}Setuid deletions:"
				pending=
				tee -a $TMP2 < $OUTPUT | column -t
				echo ""
			fi

			sort +9 $TMP2 $CUR $TMP1 | \
			    sed -e 's/[	 ][	 ]*/ /g' | uniq -u > $OUTPUT
			if [ -s $OUTPUT ] ; then
				echo "${pending}Setuid changes:"
				pending=
				column -t $OUTPUT
				echo ""
			fi

			cp $CUR $BACK
			cp $TMP1 $CUR
		fi
	else
		echo "${pending}Setuid additions:"
		pending=
		column -t $TMP1
		echo ""
		cp $TMP1 $CUR
	fi
fi

# Check for block and character disk devices that are readable or writeable
# or not owned by root.operator.
>$TMP1
DISKLIST="ccd dk fd hd hk hp jb kra ra rb rd rl rx rz sd up vnd wd xd"
for i in $DISKLIST; do
	egrep "^b.*/${i}[0-9][0-9]*[B-H]?[a-p]$"  $LIST >> $TMP1
	egrep "^c.*/r${i}[0-9][0-9]*[B-H]?[a-p]$"  $LIST >> $TMP1
done

awk '$3 != "root" || $4 != "operator" || $1 !~ /.rw-r-----/ \
	{ printf("Disk %s is user %s, group %s, permissions %s.\n", \
	    $11, $3, $4, $1); }' < $TMP1 > $OUTPUT
if [ -s $OUTPUT ] ; then
	echo "\nChecking disk ownership and permissions."
	cat $OUTPUT
	echo ""
fi

FIELDS1=1.1,1.2,1.3,1.4,1.5,1.6,1.7,1.8,1.9,1.10,0
FIELDS2=2.1,2.2,2.3,2.4,2.5,2.6,2.7,2.8,2.9,2.10,0
# Display any changes in the device file list.
egrep -a '^[bc]' $LIST | sort +10 | \
    join -o $FIELDS2 -111 -211 -v2 /dev/null - > $TMP1
if [ -s $TMP1 ] ; then
	CUR=/var/backups/device.current
	BACK=/var/backups/device.backup

	if [ -s $CUR ] ; then
		if cmp -s $CUR $TMP1 ; then
			:
		else
			> $TMP2
			join -o $FIELDS2 -111 -211 -v2 $CUR $TMP1 > $OUTPUT
			if [ -s $OUTPUT ] ; then
				echo "Device additions:"
				tee -a $TMP2 < $OUTPUT | column -t
				echo ""
			fi

			join -o $FIELDS1 -111 -211 -v1 $CUR $TMP1 > $OUTPUT
			if [ -s $OUTPUT ] ; then
				echo "Device deletions:"
				tee -a $TMP2 < $OUTPUT | column -t
				echo ""
			fi

			# Report any block device change.  Ignore character
			# devices, only the name is significant.
			cat $TMP2 $CUR $TMP1 | \
			sed -e '/^c/d' | \
			sort +10 | \
			sed -e 's/[	 ][	 ]*/ /g' | \
			uniq -u > $OUTPUT
			if [ -s $OUTPUT ] ; then
				echo "Block device changes:"
				column -t $OUTPUT
				echo ""
			fi

			cp $CUR $BACK
			cp $TMP1 $CUR
		fi
	else
		echo "Device additions:"
		column -t $TMP1
		echo ""
		cp $TMP1 $CUR
	fi
fi

# Check special files.
# Check system binaries.
#
# Create the mtree tree specifications using:
#
#	mtree -cx -p DIR -K md5digest,type >/etc/mtree/DIR.secure
#	chown root:wheel /etc/mtree/DIR.secure
#	chmod 600 /etc/mtree/DIR.secure
#
# Note, this is not complete protection against Trojan horsed binaries, as
# the hacker can modify the tree specification to match the replaced binary.
# For details on really protecting yourself against modified binaries, see
# the mtree(8) manual page.
if [ -d /etc/mtree ] ; then
	cd /etc/mtree
	mtree -e -l -p / -f /etc/mtree/special > $OUTPUT
	if [ -s $OUTPUT ] ; then
		echo "\nChecking special files and directories."
		echo "Output format is:\n\tfilename:"
		echo "\t\tcriteria (shouldbe, reallyis)"
		cat $OUTPUT
		echo "\nIf this message bugs you, use:"
		echo "\tmtree -e -p / -f /etc/mtree/special -U"
	fi

	> $OUTPUT
	for file in *.secure; do
		[ $file = '*.secure' ] && continue
		tree=$(sed -n -e '3s/.* //p' -e 3q $file)
		mtree -f $file -p $tree > $TMP1
		if [ -s $TMP1 ] ; then
			echo "\nChecking ${tree}:" >> $OUTPUT
			cat $TMP1 >> $OUTPUT
		fi
	done
	if [ -s $OUTPUT ] ; then
		echo "\nChecking system binaries:"
		cat $OUTPUT
	fi
else
	echo /etc/mtree is missing
fi

# Record a list of installed packages too; be sure to record
# the change to emptiness if previously recorded, but to not
# complain if no MirPorts Framework package tools installed.
if [[ -s /var/backups/pkglist || -x /usr/mpkg/sbin/pkg_info ]]; then
	if [[ -x /usr/mpkg/sbin/pkg_info ]]; then
		/usr/mpkg/sbin/pkg_info | sort
	else
		:
	fi >/var/backups/pkglist
fi

# List of files that get backed up and checked for any modifications.
# We try to use GNU RCS for versioning backups, otherwise, rotate: Each
# file is expected to have two backups, /var/backups/file.{current,backup}.
# Any changes cause the files to rotate.
if [ -s /etc/changelist ] ; then
	# Handle /etc/changelist.local
	if R=$(mktemp); then
		cat /etc/changelist >$R
		[ -e /etc/changelist.local ] && \
		    cat /etc/changelist.local >>$R
	else
		R=/etc/changelist
	fi
	# Now check
	_stripcom $R | while read file; do
		case $file {
		(+*)	fback -m "${file#+}" ;;
		(-*)	fback -n "${file#-}" ;;
		(/*)	fback -- "${file}" ;;
		}
	done

	for file in $(egrep -v "^(#|\+|$MP)" $R); do
		fback -- "$file"
	done
	for file in $(egrep "^\+" $R); do
		fback -m "${file#+}"
	done
	[ /etc/changelist = $R ] || rm -f $R
fi

# Make backups of the labels for any mounted disks and produce diffs
# when they change.
for d in `df -ln | sed -n 's:^/dev/\([a-z]*[0-9]*\)[a-p].*$:\1:p' | sort -u`; do
	if disklabel $d >$DIR/_disklabel 2>&1; then
		fback -- $DIR/_disklabel disklabel.$d
	fi
done