Miscellany

#!/bin/sh

# Stop iptables
/etc/init.d/iptables stop

# Flush tables
iptables -F

# Set policies
iptables -P INPUT DROP
iptables -P FORWARD DROP
iptables -P OUTPUT ACCEPT

# Allow everything on loopback
iptables -A INPUT -i lo -s 127.0.0.1 -d 127.0.0.1 -j ACCEPT

# Allow established connections
iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT

# Allow connections to servers
iptables -A INPUT -p tcp --dport 22 -j ACCEPT       # SSH
iptables -A INPUT -p tcp --dport 25 -j ACCEPT       # SMTP
iptables -A INPUT -p tcp --dport 80 -j ACCEPT       # HTTP
iptables -A INPUT -p tcp --dport 110 -j ACCEPT      # POP3
iptables -A INPUT -p tcp --dport 143 -j ACCEPT      # IMAP
iptables -A INPUT -p tcp --dport 443 -j ACCEPT      # HTTPS
iptables -A INPUT -p tcp --dport 993 -j ACCEPT      # IMAP-SSL
iptables -A INPUT -p tcp --dport 995 -j ACCEPT      # POP3-SSL
iptables -A INPUT -p tcp --dport 8767 -j ACCEPT     # TeamSpeak
iptables -A INPUT -p udp --dport 8767 -j ACCEPT     # TeamSpeak
iptables -A INPUT -p tcp --dport 6667:6669 -j ACCEPT    # IRCd
iptables -A INPUT -p tcp --dport 6690:6699 -j ACCEPT    # IRCd-SSL
iptables -A INPUT -p tcp --dport 7776 -j ACCEPT # IRCd-link

# Save config and start iptables
/etc/init.d/iptables save
/etc/init.d/iptables start