src/initscripts/system/suricata

   1 #!/bin/sh
   2 ########################################################################
   3 # Begin $rc_base/init.d/suricata
   4 #
   5 # Description : Suricata Initscript
   6 #
   7 # Author      : Stefan Schantl <stefan.schantl@ipfire.org>
   8 #
   9 # Version     : 01.02
  10 #
  11 # Notes       :
  12 #
  13 ########################################################################
  14
  15 . /etc/sysconfig/rc
  16 . ${rc_functions}
  17
  18 PATH=/usr/local/sbin:/usr/local/bin:/bin:/usr/bin:/sbin:/usr/sbin; export PATH
  19
  20 eval $(/usr/local/bin/readhash /var/ipfire/suricata/settings)
  21 eval $(/usr/local/bin/readhash /var/ipfire/ethernet/settings)
  22
  23 # Name of the firewall chains.
  24 IPS_INPUT_CHAIN="IPS_INPUT"
  25 IPS_FORWARD_CHAIN="IPS_FORWARD"
  26 IPS_OUTPUT_CHAIN="IPS_OUTPUT"
  27
  28 # Optional options for the Netfilter queue.
  29 NFQ_OPTS="--queue-bypass "
  30
  31 # Array containing the 4 possible network zones.
  32 network_zones=( red green blue orange )
  33
  34 # Array to store the network zones weather the IPS is enabled for.
  35 enabled_ips_zones=()
  36
  37 # Mark and Mask options.
  38 MARK="0x70000000"
  39 MASK="0x70000000"
  40
  41 # PID file of suricata.
  42 PID_FILE="/var/run/suricata.pid"
  43
  44 # Function to get the amount of CPU cores of the system.
  45 function get_cpu_count {
  46         CPUCOUNT=0
  47
  48         # Loop through "/proc/cpuinfo" and count the amount of CPU cores.
  49         while read line; do
  50                 [ "$line" ] && [ -z "${line%processor*}" ]  && ((CPUCOUNT++))
  51         done </proc/cpuinfo
  52
  53         # Limit to a maximum of 16 cores, because suricata does not support more than
  54         # 16 netfilter queues at the moment.
  55         if [ $CPUCOUNT -gt "16" ]; then
  56                 echo "16"
  57         else
  58                 echo $CPUCOUNT
  59         fi
  60 }
  61
  62 # Function to flush the firewall chains.
  63 function flush_fw_chain {
  64         # Call iptables and flush the chains
  65         iptables -F "$IPS_INPUT_CHAIN"
  66         iptables -F "$IPS_FORWARD_CHAIN"
  67         iptables -F "$IPS_OUTPUT_CHAIN"
  68 }
  69
  70 # Function to create the firewall rules to pass the traffic to suricata.
  71 function generate_fw_rules {
  72         cpu_count=$(get_cpu_count)
  73
  74         # Loop through the array of network zones.
  75         for zone in "${network_zones[@]}"; do
  76                 # Convert zone into upper case.
  77                 zone_upper=${zone^^}
  78
  79                 # Generate variable name for checking if the IDS is
  80                 # enabled on the zone.
  81                 enable_ids_zone="ENABLE_IDS_$zone_upper"
  82
  83                 # Check if the IDS is enabled for this network zone.
  84                 if [ "${!enable_ids_zone}" == "on" ]; then
  85                         # Check if the current processed zone is "red" and the configured type is PPPoE dialin.
  86                         if [ "$zone" == "red" ] && [ "$RED_TYPE" == "PPPOE" ]; then
  87                                 # Set device name to ppp0.
  88                                 network_device="ppp0"
  89                         else
  90                                 # Generate variable name which contains the device name.
  91                                 zone_name="$zone_upper"
  92                                 zone_name+="_DEV"
  93
  94                                 # Grab device name.
  95                                 network_device=${!zone_name}
  96                         fi
  97
  98                         # Add the network device to the array of enabled zones.
  99                         enabled_ips_zones+=( "$network_device" )
 100                 fi
 101         done
 102
 103         # Assign NFQ_OPTS
 104         NFQ_OPTIONS=$NFQ_OPTS
 105
 106         # Check if there are multiple cpu cores available.
 107         if [ "$cpu_count" -gt "1" ]; then
 108                 # Balance beetween all queues.
 109                 NFQ_OPTIONS+="--queue-balance 0:$(($cpu_count-1))"
 110                 NFQ_OPTIONS+=" --queue-cpu-fanout"
 111         else
 112                 # Send all packets to queue 0.
 113                 NFQ_OPTIONS+="--queue-num 0"
 114         fi
 115
 116         # Flush the firewall chains.
 117         flush_fw_chain
 118
 119         # Check if the array of enabled_ips_zones contains any elements.
 120         if [[ ${enabled_ips_zones[@]} ]]; then
 121                 # Loop through the array and create firewall rules.
 122                 for enabled_ips_zone in "${enabled_ips_zones[@]}"; do
 123                         # Create rules queue input and output related traffic and pass it to the IPS.
 124                         iptables -I "$IPS_INPUT_CHAIN" -i "$enabled_ips_zone" -m mark ! --mark "$MARK"/"$MASK" -j NFQUEUE $NFQ_OPTIONS
 125                         iptables -I "$IPS_OUTPUT_CHAIN" -o "$enabled_ips_zone" -m mark ! --mark "$MARK"/"$MASK" -j NFQUEUE $NFQ_OPTIONS
 126
 127                         # Create rules which are required to handle forwarded traffic.
 128                         for enabled_ips_zone_forward in "${enabled_ips_zones[@]}"; do
 129                                 iptables -I "$IPS_FORWARD_CHAIN" -i "$enabled_ips_zone" -o "$enabled_ips_zone_forward" -m mark ! --mark "$MARK"/"$MASK" -j NFQUEUE $NFQ_OPTIONS
 130                         done
 131                 done
 132
 133                 # Clear repeat bit, so that it does not confuse IPsec or QoS
 134                 iptables -A "${IPS_INPUT_CHAIN}" -j MARK --set-xmark "0x0/${MASK}"
 135                 iptables -A "${IPS_FORWARD_CHAIN}" -j MARK --set-xmark "0x0/${MASK}"
 136                 iptables -A "${IPS_OUTPUT_CHAIN}" -j MARK --set-xmark "0x0/${MASK}"
 137         fi
 138 }
 139
 140 case "$1" in
 141         start)
 142                 # Get amount of CPU cores.
 143                 cpu_count=$(get_cpu_count)
 144
 145                 # Numer of NFQUES.
 146                 NFQUEUES=
 147
 148                 for i in $(seq 0 $((cpu_count-1)) ); do
 149                         NFQUEUES+="-q $i "
 150                 done
 151
 152                 # Check if the IDS should be started.
 153                 if [ "$ENABLE_IDS" == "on" ]; then
 154                         # Start the IDS.
 155                         boot_mesg "Starting Intrusion Detection System..."
 156                         /usr/bin/suricata -c /etc/suricata/suricata.yaml -D $NFQUEUES >/dev/null 2>/dev/null
 157                         evaluate_retval
 158
 159                         # Allow reading the pidfile.
 160                         chmod 644 $PID_FILE
 161
 162                         # Flush the firewall chain
 163                         flush_fw_chain
 164
 165                         # Generate firewall rules
 166                         generate_fw_rules
 167                 fi
 168         ;;
 169
 170         stop)
 171                 boot_mesg "Stopping Intrusion Detection System..."
 172                 killproc -p $PID_FILE /var/run
 173
 174                 # Flush firewall chain.
 175                 flush_fw_chain
 176
 177                 # Remove suricata control socket.
 178                 rm /var/run/suricata/* >/dev/null 2>/dev/null
 179
 180                 # Trash remain pid file if still exists.
 181                 rm -f $PID_FILE >/dev/null 2>/dev/null
 182
 183                 # Don't report returncode of rm if suricata was not started
 184                 exit 0
 185         ;;
 186
 187         status)
 188                 statusproc /usr/bin/suricata
 189                 ;;
 190
 191         restart)
 192                 $0 stop
 193                 $0 start
 194                 ;;
 195         reload)
 196                 # Send SIGUSR2 to the suricata process to perform a reload
 197                 # of the ruleset.
 198                 kill -USR2 $(pidof suricata)
 199
 200                 # Flush the firewall chain.
 201                 flush_fw_chain
 202
 203                 # Generate firewall rules.
 204                 generate_fw_rules
 205                 ;;
 206
 207         *)
 208                 echo "Usage: $0 {start|stop|restart|reload|status}"
 209                 exit 1
 210                 ;;
 211 esac
 212
 213 chmod 644 /var/log/suricata/* 2>/dev/null
 214
 215 # End $rc_base/init.d/suricata