tools/linesync/linesync.sh

   1 #!/bin/sh
   2 # linesync.sh, Copyright (c) 2002 Arjen Wolfs
   3 # 20020604, sengaia@undernet.org
   4 # 20050417, daniel@undernet.org  - modified for u2.10.12
   5 # $Id: linesync.sh,v 1.5 2005/04/17 16:59:49 entrope Exp $
   6 #
   7 # The code contained is in this file is licenced under the terms
   8 # and conditions as specified in the GNU General Public License.
   9 #
  10 # linesync.sh - centralized ircd.conf updates.
  11 # The purpose of this little shell script is to allow a section of an ircd.conf to be
  12 # updated from a central location. Hence it is intended to facilitate the automated
  13 # distribution of Kill, Jupe, Quarantine and Uworld lines; or any other .conf lines you
  14 # may wish to keep synchronized accross all servers on a network.
  15 #
  16 # This script will download a file called linesync from a specified web server (see
  17 # below for configuration), and calculate an md5sum from it. It will then download
  18 # a file called linesync.sum from a configurable number of other web servers and
  19 # compare the contents of these files against the checksum calculated. If any of the
  20 # downloaded checksums mismatch, the program will abort. This provides security to
  21 # the centralized update mechanism - in order for it to be compromised, multiple
  22 # web servers would have to compromised.
  23 #
  24 # If all checksums match, the script inspects the .conf lines contained within the
  25 # downloaded file. If any .conf lines are found that are not specifically allowed,
  26 # the program will abort. This will prevent malicious/dangerous .conf lines (such as
  27 # Operator or Connect lines) from being inserted into ircd.conf.
  28 #
  29 # If all the checks mentioned above are passed, the script checks ircd.conf for a section
  30 # that begins with "# BEGIN LINESYNC", and ends with "# END LINESYNC". The section contained
  31 # between these two comments is the section maintained by this program. If these lines are not
  32 # found in the ircd.conf, they will be appended to it.
  33 # Next, the script will build a new ircd.conf by removing all lines present between the two
  34 # commented lines mentioned above, and replace them with the contents of the file downloaded.
  35 #
  36 # Once this has been completed, ircd.conf is backed up and replaced with the newly built version,
  37 # and ircd will be rehashed.
  38 #
  39 # Configuration: This script requires two parameters - the full path to your ircd.conf, and the
  40 # full path to your ircd.pid. It will look for a configuration file called linesync.conf in the
  41 # same directory as ircd.conf. See the included sample linesync.conf for information on how to
  42 # set it up. Obviously, you will need to have web server(s) to use for the distribution of your
  43 # .conf update and checksums. This script requires the presence of wget and md5sum, and various
  44 # other programs that should be present by default on any Unix system.
  45 #
  46 # This program should be run from crontab, i.e something like:
  47 # 0 0 * * * /home/irc/bin/linesync.sh /home/irc/lib/ircd.conf /home/irc/lib/ircd.pid
  48 #
  49 # This program has been tested on and works on FreeBSD, Solaris, and Linux.
  50 # md5sum is included in GNU textutils.
  51 #
  52 #       Good Luck!
  53 #       Arjen Wolfs (sengaia@undernet.org), June 9 2002.
  54 #
  55
  56 # This checks for the presence of an executable file in $PATH
  57 locate_program() {
  58         if [ ! -x "`which $1 2>&1`" ]; then
  59                 echo "You don't seem to have $1. Sorry."
  60                 exit 1
  61         fi
  62 }
  63
  64 # This checks for the presence of any file
  65 check_file() {
  66         if [ ! -f "$1" ]; then
  67                 echo "There doesn't appear to be a $1. Sorry."
  68                 exit 1
  69         fi
  70 }
  71
  72 # Try to find programs we will need
  73 locate_program wget && locate_program egrep && locate_program diff
  74
  75 # try to find GNU awk
  76 awk_cmd=`which gawk`
  77 if [ $? -ne 0 ]; then
  78         awk_cmd=""
  79 fi
  80
  81 # try to find an appropriate md5 program
  82 # BSD md5 capability courtesy of spale
  83 md5_cmd=`which md5sum`
  84 if [ -z "$md5_cmd" ]; then
  85         md5_cmd=`which md5`
  86         if [ -z "$md5_cmd" ]; then
  87                 echo "No MD5 capable programs found (I looked for md5sum and md5)."
  88                 exit
  89         else
  90                 md5_cmd="$md5_cmd -q"
  91         fi
  92 fi
  93
  94 if [ -z "$awk_cmd" ]; then
  95         locate_program awk
  96         is_gawk=`echo | awk --version | head -1 | egrep '^GNU.+$'`
  97         if [ -z "$is_gawk" ]; then
  98                 echo "Your version of awk is not GNU awk. Sorry."
  99                 exit 1
 100         fi
 101         awk_cmd="awk"
 102 fi
 103
 104 # Check for required command line parameters
 105 if [ -z "$1" -o -z "$2" ]; then
 106         echo "Usage: $0 <conf_path> <pid_path>"
 107         echo "      <conf_path>     Full path to ircd.conf (/home/irc/lib/ircd.conf)"
 108         echo "      <pid_path>      Full path to ircd.pid (/home/irc/lib/ircd.pid)"
 109         exit 1
 110 fi
 111
 112 # check and set up stuff
 113 diff_cmd="diff"
 114 cpath=$1
 115 ppath=$2
 116 check_file $cpath
 117 dpath=`dirname $cpath`
 118 lpath="$dpath/linesync.conf"
 119 check_file $lpath
 120 save_dir=$PWD; cd $dpath
 121 tpath=$PWD; cd $save_dir
 122 tmp_path="$dpath/tmp"
 123 mkdir $tmp_path > /dev/null 2>&1
 124
 125 # load and check configuration
 126 . $lpath
 127 if [ -z "$LINE_SERVER" -o -z "$LINE_CHECK" -o -z "$ALLOWED_LINES" ]; then
 128         echo "Please setup $lpath correctly."
 129         exit 1
 130 fi
 131
 132 # Not all versions of date support %s, work around it
 133 TS=`date +%Y%m%d%H%M%S`
 134 TMPFILE="$tmp_path/linesync.$TS"
 135 LSFILE="$LINE_SERVER""linesync"
 136 # Attempt to download our .conf update
 137 wget --cache=off --quiet --output-document=$TMPFILE $LSFILE > /dev/null 2>&1
 138 if [ ! -s "$TMPFILE" ]; then
 139         echo "Unable to retrieve $LSFILE. Sorry."
 140         rm $TMPFILE > /dev/null 2>&1
 141         exit 1
 142 fi
 143
 144 # Check whether the file contains any disallowed .conf lines
 145 bad_lines=`egrep '^[^'$ALLOWED_LINES'|#]+' $TMPFILE`
 146 if [ ! -z "$bad_lines" ]; then
 147         echo "The file downloaded in $TMPFILE contains the following disallowed line(s):"
 148         echo $bad_lines
 149         exit 1
 150 fi
 151
 152 # Check whether somebody tried to sneak a second block onto some line
 153 bad_lines=`egrep -i '}[         ]*;[    ]*[a-z]+[       ]*{' $TMPFILE`
 154 if [ ! -z "$bad_lines" ] ; then
 155         echo "The file downloaded in $TMPFILE contains the following multi-block line(s):"
 156         echo $bad_lines
 157         exit 1
 158 fi
 159
 160 # check our ircd.conf
 161 ircd_setup=`egrep '^# (BEGIN|END) LINESYNC$' $cpath|wc -l`
 162 if [ $ircd_setup != 2 ]; then
 163         cp $cpath $cpath.orig
 164         echo "Performing initial merge on $cpath, original file saved as $cpath.orig."
 165
 166         echo "# Do NOT remove the following line, linesync.sh depends on it!" >> $cpath
 167         echo "# BEGIN LINESYNC" >> $cpath
 168         echo "# END LINESYNC" >> $cpath
 169         echo "# Do not remove the previous line, linesync.sh depends on it!" >> $cpath
 170
 171         # Do an initial merge to remove duplicates
 172         inpath="$tmp_path/linesync.tmp.$TS"
 173         $awk_cmd '
 174         {
 175                 if (!loaded_template) {
 176                         command="cat " tempfile; tlines=0;
 177                         while ((command | getline avar) > 0) { template[tlines]=avar; tlines++ }
 178                         close(command)
 179                         loaded_template++
 180                 }
 181                 dup_line=0
 182                 for (i=0; i<tlines; i++) {
 183                         if (tolower($0)==tolower(template[i])) { dup_line++; break }
 184                 }
 185                 if (!dup_line) print $0
 186         } ' tempfile=$TMPFILE < $cpath > $inpath
 187 else
 188         inpath=$cpath
 189 fi
 190
 191 # Get the checksum
 192 CKSUM=`$md5_cmd $TMPFILE|cut -d' ' -f1`
 193
 194 check_file="$tmp_path/linesync.sum.$TS"
 195 for ck_server in $LINE_CHECK; do
 196         sumfile="$ck_server""linesync.sum"
 197         wget --cache=off --quiet --output-document=$check_file $sumfile > /dev/null 2>&1
 198         if [ ! -s "$check_file" ]; then
 199                 echo "Unable to retrieve checksum from $sumfile"
 200                 exit 1
 201         fi
 202         if [ "$CKSUM" != "`cat $check_file`" ]; then
 203                 echo "Checksum retrieved from $sumfile does not match!"
 204                 exit 1
 205         fi
 206         rm -f $check_file
 207 done
 208 # It all checks out, proceed...
 209
 210 # Replace the marked block in ircd.conf with the new version
 211
 212 $awk_cmd '
 213 $0=="# BEGIN LINESYNC" { chop++; print; next }
 214 $0=="# END LINESYNC" {
 215         command="cat " syncfile
 216         while ((command | getline avar) > 0) { print avar }
 217         close(command)
 218         chop--
 219 }
 220 { if (!chop) print $0 }
 221 ' syncfile=$TMPFILE < $inpath > $tmp_path/linesync.new.$TS
 222
 223 # run a diff between current and new confs to see if we updated anything
 224 # no point sending the ircd a -HUP if this is not needed, especially on a
 225 # busy network, such as Undernet.
 226 diff=`$diff_cmd $cpath $tmp_path/linesync.new.$TS`
 227 if [ ! -z "$diff" ]; then
 228         # Changes were detected
 229
 230         # Back up the current ircd.conf and replace it with the new one
 231         cp $cpath  $dpath/ircd.conf.bk
 232         cp $tmp_path/linesync.new.$TS $cpath
 233
 234         # Rehash ircd (without caring wether or not it succeeds)
 235         kill -HUP `cat $ppath 2>/dev/null` > /dev/null 2>&1
 236 fi
 237
 238 # (Try to) clean up
 239 rm -rf $tmp_path > /dev/null 2>&1
 240
 241 # That's it...