rc.chk

:
#
#  Usage: rc.chk
#
#  This checks pathnames and files inside the shell script files /etc/rc*
# for writability.
#
#  Mechanism:  The commands inside the files /etc/rc* are executed when
# the machine is booted.  This shell script greps for commands/paths that
# are of these forms:
#
#	/path/command			# or whatever
#		or
#	PATH=:/bin:/usr/bin:.		# or whatever
#		or
#	MYVAR=`/path/command`		# or whatever
#	
#  It then takes each potential problem-string and uses the program
# "is_writable" to determine if it is world writable.  All results are
# echoed to standard output.
#
# 12 Apr 90, Mark Plumbly made it ignore lines starting with rm -f
# (popular in rc files) and fixed my code so it would ignore everything
# after a ">".
#
SED=/bin/sed
CAT=/bin/cat
RM=/bin/rm
AWK=/bin/awk
LS=/bin/ls
TEST=/bin/test
EGREP=/usr/bin/egrep
ECHO=/bin/echo
SORT=/usr/bin/sort
FIND=/bin/find

# temp file for stuff:
FOO_RC="./rc.foo.$$"
FOO_RC2="./rc.foo2.$$"

# CHANGE THIS LINE OR PUT IN FILE NAMES IF/AS NEEDED!
#    (for example: init_files="/etc/rc /etc/rc.local")
#
# init_files=`$LS /etc/*rc /etc/rc* /etc/rc*.d/* /etc/shutdown.d/* /etc/inittab | $SORT -u`

potential_files="/etc/*rc /etc/rc*"
if $TEST -d /etc/shutdown.d ; then
	potential_files=$potential_files" /etc/shutdown.d"
	fi
if $TEST -f /etc/inittab ; then
	potential_files=$potential_files" /etc/inittab"
	fi
init_files=`$FIND $potential_files -print | $SORT -u`

#
#  This should get all paths in /etc/rc* files; at least two types here.
# First type starts with a "/", the second is either in the form :
#
#	PATH=:/bin:/usr/bin:.		# or whatever
# or
#	MYVAR=`/bin/echo "hello"`	# or whatever
#
#   Notice also I strip out any references to /tmp, /usr/tmp,
# /dev/*ty's, and /dev/null.
#
# 12 Apr mdp: 	Modified to remove "> file" as well as ">file"
#		and remove "rm -f file" (this removes a few bogus ones).
#		(i.e. things which are written to or removed only are ignored).
#

#  You can try this, or use the old method...
# for file in $init_files
#  	do
# 	if $TEST -s $file ; then
#  		./chk_strings $file
# 		fi
#   	done
# exit

for file in $init_files
	do
	if $TEST -f "$file" ; then
		$AWK '{ if (substr($1,1,1)== "#") next; \
		for (i=1;i<=NF;i++) \
			{ first=substr($i,1,1);		\
				if (first==">"||first=="#"||first=="$")	\
					break;			\
				else if ($i == "rm")		\
					break;			\
				else if (first == "/")		\
					print "\"'$file'\"", $i;\
				}				\
			}' $file |
		$SED -e s/\"//g -e s/\'//g -e s/\`//g -e s/\;// |
		$EGREP -v "/dev/.*ty|/tmp|/usr/tmp|/dev/null"
		fi
		done | sort -u >> $FOO_RC2

#
#  Ok -- $FOO_RC has a format like thus:
# /etc/rc.local /bin/foofile
#
#  We want to kill off all dups in the second field:
$AWK '{dup[$2] = $1}
	END { for (i in dup) print dup[i], i;}' $FOO_RC2 | $SORT > $FOO_RC

#  First, get the ones starting with "/":
#
#   DANGER!  DANGER!  DANGER Will Robinson! Awk runs out of room ("bails
# out") if too many files are here....
# for i in `$CAT $FOO_RC`
cat $FOO_RC | while read i
	do
	target=`$ECHO $i | $SED 's/.* //'`
	if $TEST -f "$target" ; then
		blame=`$ECHO $i | $SED 's/ .*$//'`
		if ./is_writable $target
			then
			$ECHO "Warning!  File $target (in $blame) is _World_ writable!"
			fi
		fi
	done

$RM -f $FOO_RC $FOO_RC2
# end of script