[3/3] initscripts/suricata: Rework creation of firewall rules.
Commit Message
The script now will use the previously introduced seperate firewall chains called
IPS_INPUT, IPS_FORWARD and IPS_OUTPUT.
The commit also creates an AND connection between the choosen network zones in the UI and
the final firwall rules.
Fixes #12062.
Signed-off-by: Stefan Schantl <stefan.schantl@ipfire.org>
---
src/initscripts/system/suricata | 78 +++++++++++++++++++++------------
1 file changed, 50 insertions(+), 28 deletions(-)
@@ -6,7 +6,7 @@
#
# Author : Stefan Schantl <stefan.schantl@ipfire.org>
#
-# Version : 01.00
+# Version : 01.01
#
# Notes :
#
@@ -20,8 +20,10 @@ PATH=/usr/local/sbin:/usr/local/bin:/bin:/usr/bin:/sbin:/usr/sbin; export PATH
eval $(/usr/local/bin/readhash /var/ipfire/suricata/settings)
eval $(/usr/local/bin/readhash /var/ipfire/ethernet/settings)
-# Name of the firewall chain.
-FW_CHAIN="IPS"
+# Name of the firewall chains.
+IPS_INPUT_CHAIN="IPS_INPUT"
+IPS_FORWARD_CHAIN="IPS_FORWARD"
+IPS_OUTPUT_CHAIN="IPS_OUTPUT"
# Optional options for the Netfilter queue.
NFQ_OPTS="--queue-bypass "
@@ -29,6 +31,9 @@ NFQ_OPTS="--queue-bypass "
# Array containing the 4 possible network zones.
network_zones=( red green blue orange )
+# Array to store the network zones weather the IPS is enabled for.
+enabled_ips_zones=()
+
# Mark and Mask options.
MARK="0x70000000"
MASK="0x70000000"
@@ -48,19 +53,18 @@ function get_cpu_count {
echo $CPUCOUNT
}
-# Function to flush the firewall chain.
+# Function to flush the firewall chains.
function flush_fw_chain {
- # Call iptables and flush the chain
- iptables -F "$FW_CHAIN"
+ # Call iptables and flush the chains
+ iptables -F "$IPS_INPUT_CHAIN"
+ iptables -F "$IPS_FORWARD_CHAIN"
+ iptables -F "$IPS_OUTPUT_CHAIN"
}
# Function to create the firewall rules to pass the traffic to suricata.
function generate_fw_rules {
cpu_count=$(get_cpu_count)
- # Flush the firewall chain.
- flush_fw_chain
-
# Loop through the array of network zones.
for zone in "${network_zones[@]}"; do
# Convert zone into upper case.
@@ -85,28 +89,46 @@ function generate_fw_rules {
network_device=${!zone_name}
fi
- # 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:$(($cpu_count-1))"
- NFQ_OPTIONS+=" --queue-cpu-fanout"
- 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 $NFQ_OPTIONS
+ # Add the network device to the array of enabled zones.
+ enabled_ips_zones+=( "$network_device" )
fi
done
- # Clear repeat bit, so that it does not confuse IPsec or QoS
- iptables -A "${FW_CHAIN}" -j MARK --set-xmark "0x0/${MASK}"
+ # 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:$(($cpu_count-1))"
+ NFQ_OPTIONS+=" --queue-cpu-fanout"
+ else
+ # Send all packets to queue 0.
+ NFQ_OPTIONS+="--queue-num 0"
+ fi
+
+ # Flush the firewall chains.
+ flush_fw_chain
+
+ # Check if the array of enabled_ips_zones contains any elements.
+ if [[ ${enabled_ips_zones[@]} ]]; then
+ # Loop through the array and create firewall rules.
+ for enabled_ips_zone in "${enabled_ips_zones[@]}"; do
+ # Create rules queue input and output related traffic and pass it to the IPS.
+ iptables -I "$IPS_INPUT_CHAIN" -i "$enabled_ips_zone" -m mark ! --mark "$MARK"/"$MASK" -j NFQUEUE $NFQ_OPTIONS
+ iptables -I "$IPS_OUTPUT_CHAIN" -o "$enabled_ips_zone" -m mark ! --mark "$MARK"/"$MASK" -j NFQUEUE $NFQ_OPTIONS
+
+ # Create rules which are required to handle forwarded traffic.
+ for enabled_ips_zone_forward in "${enabled_ips_zones[@]}"; do
+ iptables -I "$IPS_FORWARD_CHAIN" -i "$enabled_ips_zone" -o "$enabled_ips_zone_forward" -m mark ! --mark "$MARK"/"$MASK" -j NFQUEUE $NFQ_OPTIONS
+ done
+ done
+
+ # Clear repeat bit, so that it does not confuse IPsec or QoS
+ iptables -A "${IPS_INPUT_CHAIN}" -j MARK --set-xmark "0x0/${MASK}"
+ iptables -A "${IPS_FORWARD_CHAIN}" -j MARK --set-xmark "0x0/${MASK}"
+ iptables -A "${IPS_OUTPUT_CHAIN}" -j MARK --set-xmark "0x0/${MASK}"
+ fi
}
case "$1" in