spacewalk.ansible/roles/iptables/templates/firewall.bash.j2

80 lines
2.1 KiB
Django/Jinja
Executable File

#!/bin/bash
# iptables firewall for common LAMP servers.
#
# This file should be located at /etc/firewall.bash, and is meant to work with
# Jeff Geerling's firewall init script.
#
# Common port reference:
# 22: SSH
# 25: SMTP
# 80: HTTP
# 123: DNS
# 443: HTTPS
# 2222: SSH alternate
# 4949: Munin
# 6082: Varnish admin
# 8080: HTTP alternate (often used with Tomcat)
# 8983: Tomcat HTTP
# 8443: Tomcat HTTPS
# 9000: SonarQube
#
# @author Jeff Geerling
# No spoofing.
if [ -e /proc/sys/net/ipv4/conf/all/rp_filter ]
then
for filter in /proc/sys/net/ipv4/conf/*/rp_filter
do
echo 1 > $filter
done
fi
# Remove all rules and chains.
iptables -F
iptables -X
# Accept traffic from loopback interface (localhost).
iptables -A INPUT -i lo -j ACCEPT
# Forwarded ports.
{# Add a rule for each forwarded port #}
{% for forwarded_port in firewall_forwarded_tcp_ports %}
iptables -t nat -I PREROUTING -p tcp --dport {{ forwarded_port.src }} -j REDIRECT --to-port {{ forwarded_port.dest }}
{% endfor %}
{% for forwarded_port in firewall_forwarded_udp_ports %}
iptables -t nat -I PREROUTING -p udp --dport {{ forwarded_port.src }} -j REDIRECT --to-port {{ forwarded_port.dest }}
{% endfor %}
# Open ports.
{# Add a rule for each open port #}
{% for port in firewall_allowed_tcp_ports %}
iptables -A INPUT -p tcp -m tcp --dport {{ port }} -j ACCEPT
{% endfor %}
{% for port in firewall_allowed_udp_ports %}
iptables -A INPUT -p tcp -m udp --dport {{ port }} -j ACCEPT
{% endfor %}
# Accept icmp ping requests.
iptables -A INPUT -p icmp -j ACCEPT
# Allow NTP traffic for time synchronization.
iptables -A OUTPUT -p udp --dport 123 -j ACCEPT
iptables -A INPUT -p udp --sport 123 -j ACCEPT
# Additional custom rules.
{% for rule in firewall_additional_rules %}
{{ rule }}
{% endfor %}
# Allow established connections:
iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
# Log EVERYTHING (ONLY for Debug).
# iptables -A INPUT -j LOG
# Log other incoming requests (all of which are dropped) at 15/minute max.
iptables -A INPUT -m limit --limit 15/minute -j LOG --log-level 7 --log-prefix "Dropped by firewall: "
# Drop all other traffic.
iptables -A INPUT -j DROP