initscripts/suricata: Generate firewall rules on start and reload
authorStefan Schantl <stefan.schantl@ipfire.org>
Wed, 30 Jan 2019 12:43:38 +0000 (13:43 +0100)
committerStefan Schantl <stefan.schantl@ipfire.org>
Wed, 30 Jan 2019 12:47:07 +0000 (13:47 +0100)
Fixes #11978

Signed-off-by: Stefan Schantl <stefan.schantl@ipfire.org>
src/initscripts/system/suricata

index 99097a8..b406b92 100644 (file)
@@ -35,52 +35,81 @@ MASK="0x2"
 # PID file of suricata.
 PID_FILE="/var/run/suricata.pid"
 
+# Function to get the amount of CPU cores of the system.
+function get_cpu_count {
+       CPUCOUNT=0
+
+       # Loop through "/proc/cpuinfo" and count the amount of CPU cores.
+       while read line; do
+               [ "$line" ] && [ -z "${line%processor*}" ]  && ((CPUCOUNT++))
+       done </proc/cpuinfo
+
+       echo $CPUCOUNT
+}
+
+# Function to create the firewall rules to pass the traffic to suricata.
+function generate_fw_rules {
+       cpu_count=$(get_cpu_count)
+
+       # Flush the firewall chain.
+       iptables -F "$FW_CHAIN"
+
+       # Loop through the array of network zones.
+       for zone in "${network_zones[@]}"; do
+               # Convert zone into upper case.
+               zone_upper=${zone^^}
+
+               # Generate variable name for checking if the IDS is
+               # enabled on the zone.
+               enable_ids_zone="ENABLE_IDS_$zone_upper"
+
+               # Check if the IDS is enabled for this network zone.
+               if [ "${!enable_ids_zone}" == "on" ]; then
+                       # Generate name of the network interface.
+                       network_device=$zone
+                       network_device+="0"
+
+                       # Assign NFQ_OPTS
+                       NFQ_OPTIONS=$NFQ_OPTS
+
+                       # Check if there are multiple cpu cores available.
+                       if [ "$cpu_count" -gt "1" ]; then
+                               # Balance beetween all queues.
+                               NFQ_OPTIONS+="--queue-balance 0:"
+                               NFQ_OPTIONS+=$(($cpu_count-1))
+                       else
+                               # Send all packets to queue 0.
+                               NFQ_OPTIONS+="--queue-num 0"
+                       fi
+
+                       # Create firewall rules to queue the traffic and pass to
+                       # the IDS.
+                       iptables -I "$FW_CHAIN" -i "$network_device" -m mark ! --mark "$MARK"/"$MASK" -j NFQUEUE $NFQ_OPTIONS
+                       iptables -I "$FW_CHAIN" -o "$network_device" -m mark ! --mark "$MARK"/"$MASK" -j NFQUEUE $NFQ_OPTIONS
+               fi
+       done
+}
+
+# Function to flush the firewall chain.
+function flush_fw_chain {
+       # Call iptables and flush the chain
+       iptables -F "$FW_CHAIN"
+}
+
 case "$1" in
         start)
                # Get amount of CPU cores.
+               cpu_count=$(get_cpu_count)
+
+               # Numer of NFQUES.
                NFQUEUES=
-               CPUCOUNT=0
-               while read line; do
-                       [ "$line" ] && [ -z "${line%processor*}" ] && NFQUEUES+="-q $CPUCOUNT " && ((CPUCOUNT++))
-               done </proc/cpuinfo
+
+               for i in $(seq 0 $cpu_count); do
+                       NFQUEUES+="-q $i "
+               done
 
                # Check if the IDS should be started.
                if [ "$ENABLE_IDS" == "on" ]; then
-                       # Loop through the array of network zones.
-                       for zone in "${network_zones[@]}"; do
-                               # Convert zone into upper case.
-                               zone_upper=${zone^^}
-
-                               # Generate variable name for checking if the IDS is
-                               # enabled on the zone.
-                               enable_ids_zone="ENABLE_IDS_$zone_upper"
-
-                               # Check if the IDS is enabled for this network zone.
-                               if [ "${!enable_ids_zone}" == "on" ]; then
-                                       # Generate name of the network interface.
-                                       network_device=$zone
-                                       network_device+="0"
-
-                                       # Assign NFQ_OPTS
-                                       NFQ_OPTIONS=$NFQ_OPTS
-
-                                       # Check if there are multiple cpu cores available.
-                                       if [ "$CPUCOUNT" -gt "1" ]; then
-                                               # Balance beetween all queues.
-                                               NFQ_OPTIONS+="--queue-balance 0:"
-                                               NFQ_OPTIONS+=$(($CPUCOUNT-1))
-                                       else
-                                               # Send all packets to queue 0.
-                                               NFQ_OPTIONS+="--queue-num 0"
-                                       fi
-
-                                       # Create firewall rules to queue the traffic and pass to
-                                       # the IDS.
-                                       iptables -I "$FW_CHAIN" -i "$network_device" -m mark ! --mark "$MARK"/"$MASK" -j NFQUEUE $NFQ_OPTIONS
-                                       iptables -I "$FW_CHAIN" -o "$network_device" -m mark ! --mark "$MARK"/"$MASK" -j NFQUEUE $NFQ_OPTIONS
-                               fi
-                       done
-
                        # Start the IDS.
                        boot_mesg "Starting Intrusion Detection System..."
                        /usr/bin/suricata -c /etc/suricata/suricata.yaml -D $NFQUEUES
@@ -88,6 +117,12 @@ case "$1" in
 
                        # Allow reading the pidfile.
                        chmod 644 $PID_FILE
+
+                       # Flush the firewall chain
+                       flush_fw_chain
+
+                       # Generate firewall rules
+                       generate_fw_rules
                fi
        ;;
 
@@ -96,7 +131,7 @@ case "$1" in
                killproc -p $PID_FILE /var/run
 
                # Flush firewall chain.
-               iptables -F $FW_CHAIN
+               flush_fw_chain
 
                # Remove suricata control socket.              
                rm /var/run/suricata/* >/dev/null 2>/dev/null
@@ -117,6 +152,12 @@ case "$1" in
                # Send SIGUSR2 to the suricata process to perform a reload
                # of the ruleset.
                kill -USR2 $(pidof suricata)
+
+               # Flush the firewall chain.
+               flush_fw_chain
+
+               # Generate firewall rules.
+               generate_fw_rules
                ;;
                 
         *)