DDoS Protection (RE:MKT Acilmiyor) [MKT]

DoS(Denial of Service) ve ya DDoS(Distrubited Denial of Service) Attack-lari baya guclu olur. Simdi bunlari engellemeyin 1 yolu. ddos.conf yaradiyoruz :

Kod:

##### Paths of the script and other files
PROGDIR="/usr/local/ddos"
PROG="/usr/local/ddos/ddos.sh"
IGNORE_IP_LIST="/usr/local/ddos/ignore.ip.list"
CRON="/etc/cron.d/ddos.cron"
APF="/etc/apf/apf"
IPT="/sbin/iptables"

##### frequency in minutes for running the script
##### Caution: Every time this setting is changed, run the script with --cron
#####          option so that the new frequency takes effect
FREQ=1

##### How many connections define a bad IP? Indicate that below.
NO_OF_CONNECTIONS=150

##### APF_BAN=1 (Make sure your APF version is atleast 0.96)
##### APF_BAN=0 (Uses iptables for banning ips instead of APF)
APF_BAN=1

##### KILL=0 (Bad IPs are'nt banned, good for interactive execution of script)
##### KILL=1 (Recommended setting)
KILL=1

##### An email is sent to the following address when an IP is banned.
##### Blank would suppress sending of mails
EMAIL_TO="root"

##### Number of seconds the banned ip should remain in blacklist.
BAN_PERIOD=600

ignore.ip.list :

Kod:

127.0.0.1

ddos.sh :

Kod:

#!/bin/sh
##############################################################################
# DDoS-Deflate version 0.6 Author: Zaf <zaf@vsnl.com>                        #
##############################################################################
# This program is distributed under the "Artistic License" Agreement         #
#                                                                            #
# The LICENSE file is located in the same directory as this program. Please  #
#  read the LICENSE file before you make copies or distribute this program   #
##############################################################################
load_conf()
{
 CONF="/usr/local/ddos/ddos.conf"
 if [ -f "$CONF" ] && [ ! "$CONF" == "" ]; then
  source $CONF
 else
  head
  echo "\$CONF not found."
  exit 1
 fi
}

head()
{
 echo "DDoS-Deflate version 0.6"
 echo "Copyright (C) 2005, Zaf <zaf@vsnl.com>"
 echo
}

showhelp()
{
 head
 echo 'Usage: ddos.sh [OPTIONS] [N]'
 echo 'N : number of tcp/udp connections (default 150)'
 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 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 -u $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/ddos/ddos.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/ddos/ddos.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/ddos'
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 | 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 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`
  if [ $EMAIL_TO != "" ]; then
   cat $BANNED_IP_MAIL | mail -s "IP addresses banned on $dt" $EMAIL_TO
  fi
  unbanip
 fi
fi
rm -f $TMP_PREFIX.*

Bu 1 yolu DDoS-dan korunmakdan.

Ve simdi Flood-Ping attack-lara karsi :
Disable Ping-flood attacks :
Ekleyin /etc/sysctl.conf:

Kod:

net.inet.icmp.bmcastecho=1
net.inet.icmp.icmplim=1

Simdi Shell-de acib immerditaly-lari duzeltelim :

Kod:

sysctl net.inet.icmp.icmplim=1
sysctl net.inet.icmp.bmcastecho=1

Ve 1 FireWall Kurmak en onemlisidir.
Basarilar )))))
&& Respect! ^_^
Avatar Fearless
Topic : http://www.millikuvvetler.net/showthread.php?t=8367