[S] Syn Deflate Script

[Paran0id]

Hi Leute, suche folgendes script was irgendwie aus dem netz verschwunden ist, alles was ich noch habe ist folgender Abschnitt:

#!/bin/sh
load_conf()
{
    CONF="/usr/local/synd/synd.conf"
    if [ -f "$CONF" ] && [ ! "$CONF" ==    "" ]; then
        source $CONF
    else
        head
        echo "\$CONF not found."
        exit 1
    fi
}

head()
{
    echo "Syn-Deflate version 0.1 alpha"
    echo "Based on Dos-Deflate - felosi <admin@nix101.com>"
    echo
}

showhelp()
{
    head
    echo 'Usage: synd.sh [OPTIONS] [N]'
    echo 'N : number of SYN_RECV connections (default 10)'
    echo 'OPTIONS:'
    echo '-h | --help: Show    this help screen'
    echo '-c | --cron: Create cron job to run this script regularly (default 1 mins)'
    echo '-k | --kill: Block the offending ip making more than N SYN_RECV connections'
}

unbanip()
{
    UNBAN_SCRIPT=`mktemp /tmp/unban.XXXXXXXX`
    TMP_FILE=`mktemp /tmp/unban.XXXXXXXX`
    UNBAN_IP_LIST=`mktemp /tmp/unban.XXXXXXXX`
    echo '#!/bin/sh' > $UNBAN_SCRIPT
    echo "sleep $BAN_PERIOD" >> $UNBAN_SCRIPT
    if [ $APF_BAN -eq 1 ]; then
        while read line; do
            echo "$APF -d $line" >> $UNBAN_SCRIPT
            echo $line >> $UNBAN_IP_LIST
        done < $BANNED_IP_LIST
    else
        while read line; do
            echo "$IPT -D INPUT -s $line -j DROP" >> $UNBAN_SCRIPT
            echo $line >> $UNBAN_IP_LIST
        done < $BANNED_IP_LIST
    fi
    echo "grep -v --file=$UNBAN_IP_LIST $IGNORE_IP_LIST > $TMP_FILE" >> $UNBAN_SCRIPT
    echo "mv $TMP_FILE $IGNORE_IP_LIST" >> $UNBAN_SCRIPT
    echo "rm -f $UNBAN_SCRIPT" >> $UNBAN_SCRIPT
    echo "rm -f $UNBAN_IP_LIST" >> $UNBAN_SCRIPT
    echo "rm -f $TMP_FILE" >> $UNBAN_SCRIPT
    . $UNBAN_SCRIPT &
}

add_to_cron()
{
    rm -f $CRON
    sleep 1
    service crond restart
    sleep 1
    echo "SHELL=/bin/sh" > $CRON
    if [ $FREQ -le 2 ]; then
        echo "0-59/$FREQ * * * * root /usr/local/synd/synd.sh >/dev/null 2>&1" >> $CRON
    else
        let "START_MINUTE = $RANDOM % ($FREQ - 1)"
        let "START_MINUTE = $START_MINUTE + 1"
        let "END_MINUTE = 60 - $FREQ + $START_MINUTE"
        echo "$START_MINUTE-$END_MINUTE/$FREQ * * * * root /usr/local/synd/synd.sh >/dev/null 2>&1" >> $CRON
    fi
    service crond restart
}


load_conf
while [ $1 ]; do
    case $1 in
        '-h' | '--help' | '?' )
            showhelp
            exit
            ;;
        '--cron' | '-c' )
            add_to_cron
            exit
            ;;
        '--kill' | '-k' )
            KILL=1
            ;;
         *[0-9]* )
            NO_OF_CONNECTIONS=$1
            ;;
        * )
            showhelp
            exit
            ;;
    esac
    shift
done

TMP_PREFIX='/tmp/synd'
TMP_FILE="mktemp $TMP_PREFIX.XXXXXXXX"
BANNED_IP_MAIL=`$TMP_FILE`
BANNED_IP_LIST=`$TMP_FILE`
echo "Banned the following ip addresses on `date`" > $BANNED_IP_MAIL
echo >>    $BANNED_IP_MAIL
BAD_IP_LIST=`$TMP_FILE`
netstat -ntu | grep SYN_RECV | awk '{print $5}' | cut -d: -f1 | sort | uniq -c | sort -nr > $BAD_IP_LIST
cat $BAD_IP_LIST
if [ $KILL -eq 1 ]; then
    IP_BAN_NOW=0
    while read line; do
        CURR_LINE_CONN=$(echo $line | cut -d" " -f1)
        CURR_LINE_IP=$(echo $line | cut -d" " -f2)
        if [ $CURR_LINE_CONN -lt $NO_OF_CONNECTIONS ]; then
            break
        fi
        IGNORE_BAN=`grep -c $CURR_LINE_IP $IGNORE_IP_LIST`
        if [ $IGNORE_BAN -ge 1 ]; then
            continue
        fi
        IP_BAN_NOW=1
        echo "$CURR_LINE_IP with $CURR_LINE_CONN SYN_RECV connections" >> $BANNED_IP_MAIL
        echo $CURR_LINE_IP >> $BANNED_IP_LIST
        echo $CURR_LINE_IP >> $IGNORE_IP_LIST
        if [ $APF_BAN -eq 1 ]; then
            $APF -d $CURR_LINE_IP
        else
            $IPT -I INPUT -s $CURR_LINE_IP -j DROP
        fi
    done < $BAD_IP_LIST
    if [ $IP_BAN_NOW -eq 1 ]; then
        dt=`date`
                hn=`hostname`
#        if [ $EMAIL_TO != "" ]; then
#            cat $BANNED_IP_MAIL | mail -s "IP addresses banned on $dt $hn" $EMAIL_TO
#        fi
        unbanip
    fi
fi
rm -f $TM

Ich hoffe ihr könnt mir helfen.

Gruß