Example webserver iptable ruleset - Revision history

Gordp at 20:48, 18 December 2012

2012-12-18T20:48:21Z

← Older revision		Revision as of 20:48, 18 December 2012
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	# and addressed to this host.)		# and addressed to this host.)

	$IPTABLES -A INPUT -m ~~state~~ --~~state~~ INVALID -j DROP		$IPTABLES -A INPUT -m conntrack --ctstate INVALID -j DROP
	$IPTABLES -A INPUT -m ~~state~~ --~~state~~ RELATED,ESTABLISHED -j ACCEPT		$IPTABLES -A INPUT -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT

	# ftp incoming		# ftp incoming
	$IPTABLES -A INPUT -p tcp -m ~~state~~ --~~state~~ NEW --dport 20 -j ACCEPT		$IPTABLES -A INPUT -p tcp -m conntrack --ctstate NEW --dport 20 -j ACCEPT
	$IPTABLES -A INPUT -p tcp -m ~~state~~ --~~state~~ NEW --dport 21 -j ACCEPT		$IPTABLES -A INPUT -p tcp -m conntrack --ctstate NEW --dport 21 -j ACCEPT

	# ssh incoming, including non-standard port (if needed)		# ssh incoming, including non-standard port (if needed)
	$IPTABLES -A INPUT -p tcp -m ~~state~~ --~~state~~ NEW --dport 22 -j ACCEPT		$IPTABLES -A INPUT -p tcp -m conntrack --ctstate NEW --dport 22 -j ACCEPT
	#$IPTABLES -A INPUT -p tcp -m ~~state~~ --~~state~~ NEW --dport 222 -j ACCEPT		#$IPTABLES -A INPUT -p tcp -m conntrack --ctstate NEW --dport 222 -j ACCEPT

	# web serving, let's allow it!		# web serving, let's allow it!
	$IPTABLES -A INPUT -p tcp -m ~~state~~ --~~state~~ NEW --dport 80 -j ACCEPT		$IPTABLES -A INPUT -p tcp -m conntrack --ctstate NEW --dport 80 -j ACCEPT

	# secure web serving, let's allow it!		# secure web serving, let's allow it!
	$IPTABLES -A INPUT -p tcp -m ~~state~~ --~~state~~ NEW --dport 443 -j ACCEPT		$IPTABLES -A INPUT -p tcp -m conntrack --ctstate NEW --dport 443 -j ACCEPT

	# amanda tape-backups; we reach out and tape things from this machine		# amanda tape-backups; we reach out and tape things from this machine
	$IPTABLES -A INPUT -p udp -m ~~state~~ --~~state~~ NEW -m udp --dport 10080 -j ACCEPT		$IPTABLES -A INPUT -p udp -m conntrack --ctstate NEW -m udp --dport 10080 -j ACCEPT
	$IPTABLES -A INPUT -p tcp -m ~~state~~ --~~state~~ NEW --dport 10082 -j ACCEPT		$IPTABLES -A INPUT -p tcp -m conntrack --ctstate NEW --dport 10082 -j ACCEPT
	$IPTABLES -A INPUT -p tcp -m ~~state~~ --~~state~~ NEW --dport 10083 -j ACCEPT		$IPTABLES -A INPUT -p tcp -m conntrack --ctstate NEW --dport 10083 -j ACCEPT

	# nagios (5666); monitor time (123), allow snmp (161)		# nagios (5666); monitor time (123), allow snmp (161)
	$IPTABLES -A INPUT -p tcp -m ~~state~~ --~~state~~ NEW --dport 5666 -j ACCEPT		$IPTABLES -A INPUT -p tcp -m conntrack --ctstate NEW --dport 5666 -j ACCEPT
	$IPTABLES -A INPUT -p udp -m udp --dport 123 -j ACCEPT		$IPTABLES -A INPUT -p udp -m udp --dport 123 -j ACCEPT
	$IPTABLES -A INPUT -p udp -m udp --dport 161 -j ACCEPT		$IPTABLES -A INPUT -p udp -m udp --dport 161 -j ACCEPT

Gordp at 20:58, 28 December 2008

2008-12-28T20:58:09Z

← Older revision		Revision as of 20:58, 28 December 2008
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	# ==============		# ==============
	# of course, accepting loopback is a good idea		# of course, accepting loopback is a good idea
	$IPTABLES -A INPUT -i lo -j ACCEPT		$IPTABLES -A INPUT -i lo -j ACCEPT

			# we will permit ping, but rate-limit type 8 to prevent DoS-attack
			$IPTABLES -A INPUT -p icmp --icmp-type 0 -j ACCEPT
			$IPTABLES -A INPUT -p icmp --icmp-type 3 -j ACCEPT
			$IPTABLES -A INPUT -p icmp --icmp-type 11 -j ACCEPT
			$IPTABLES -A INPUT -p icmp --icmp-type 8 -m limit --limit 1/second -j ACCEPT

	# (Applies to packets entering our network interface from the network,		# (Applies to packets entering our network interface from the network,

Jjaythomas at 18:47, 6 February 2008

2008-02-06T18:47:33Z

← Older revision		Revision as of 18:47, 6 February 2008
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	# web serving, let's allow it!		# web serving, let's allow it!
	$IPTABLES -A INPUT -p tcp -m state --state NEW --dport 80 -j ACCEPT		$IPTABLES -A INPUT -p tcp -m state --state NEW --dport 80 -j ACCEPT

			# secure web serving, let's allow it!
			$IPTABLES -A INPUT -p tcp -m state --state NEW --dport 443 -j ACCEPT

	# amanda tape-backups; we reach out and tape things from this machine		# amanda tape-backups; we reach out and tape things from this machine

Gordp at 16:41, 4 February 2008

2008-02-04T16:41:47Z

← Older revision		Revision as of 16:41, 4 February 2008
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	# amanda tape-backups; we reach out and tape things from this machine		# amanda tape-backups; we reach out and tape things from this machine
	$IPTABLES -A INPUT -p udp -m udp --dport 10080 -j ACCEPT		$IPTABLES -A INPUT -p udp -m state --state NEW -m udp --dport 10080 -j ACCEPT
	$IPTABLES -A INPUT -p tcp -m state --state NEW --dport 10082 -j ACCEPT		$IPTABLES -A INPUT -p tcp -m state --state NEW --dport 10082 -j ACCEPT
	$IPTABLES -A INPUT -p tcp -m state --state NEW --dport 10083 -j ACCEPT		$IPTABLES -A INPUT -p tcp -m state --state NEW --dport 10083 -j ACCEPT

Gordp at 18:15, 30 January 2008

2008-01-30T18:15:33Z

← Older revision		Revision as of 18:15, 30 January 2008
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	# nagios (5666); monitor time (123), allow snmp (161)		# nagios (5666); monitor time (123), allow snmp (161)
	$IPTABLES -A INPUT -p tcp -m state --state NEW --dport 5666 -j ACCEPT		$IPTABLES -A INPUT -p tcp -m state --state NEW --dport 5666 -j ACCEPT
	$IPTABLES -A INPUT -p udp -m ~~state --state NEW~~ --dport 123 -j ACCEPT		$IPTABLES -A INPUT -p udp -m udp --dport 123 -j ACCEPT
	$IPTABLES -A INPUT -p udp -m ~~state --state NEW~~ --dport 161 -j ACCEPT		$IPTABLES -A INPUT -p udp -m udp --dport 161 -j ACCEPT

Gordp at 18:09, 30 January 2008

2008-01-30T18:09:25Z

← Older revision		Revision as of 18:09, 30 January 2008
Line 38:		Line 38:

	# amanda tape-backups; we reach out and tape things from this machine		# amanda tape-backups; we reach out and tape things from this machine
	$IPTABLES -A INPUT -p udp -m ~~state --state NEW~~ --dport 10080 -j ACCEPT		$IPTABLES -A INPUT -p udp -m udp --dport 10080 -j ACCEPT
	$IPTABLES -A INPUT -p tcp -m state --state NEW --dport 10082 -j ACCEPT		$IPTABLES -A INPUT -p tcp -m state --state NEW --dport 10082 -j ACCEPT
	$IPTABLES -A INPUT -p tcp -m state --state NEW --dport 10083 -j ACCEPT		$IPTABLES -A INPUT -p tcp -m state --state NEW --dport 10083 -j ACCEPT
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	# (Applies to packets sent to the network interface from local processes)		# (Applies to packets sent to the network interface from local processes)

	$IPTABLES -A OUTPUT ~~-m state --state RELATED,ESTABLISHED~~ -j ACCEPT		$IPTABLES -A OUTPUT -j ACCEPT

	Invoke and make these rules effective:		Invoke and make these rules effective:

Gordp at 17:36, 30 January 2008

2008-01-30T17:36:51Z

← Older revision		Revision as of 17:36, 30 January 2008
Line 36:		Line 36:
	# web serving, let's allow it!		# web serving, let's allow it!
	$IPTABLES -A INPUT -p tcp -m state --state NEW --dport 80 -j ACCEPT		$IPTABLES -A INPUT -p tcp -m state --state NEW --dport 80 -j ACCEPT

	# amanda tape-backups; we reach out and tape things from this machine		# amanda tape-backups; we reach out and tape things from this machine
	$IPTABLES -A INPUT -p udp -m state --state NEW --dport 10080 -j ACCEPT		$IPTABLES -A INPUT -p udp -m state --state NEW --dport 10080 -j ACCEPT

Gordp at 17:36, 30 January 2008

2008-01-30T17:36:34Z

← Older revision		Revision as of 17:36, 30 January 2008
Line 36:		Line 36:
	# web serving, let's allow it!		# web serving, let's allow it!
	$IPTABLES -A INPUT -p tcp -m state --state NEW --dport 80 -j ACCEPT		$IPTABLES -A INPUT -p tcp -m state --state NEW --dport 80 -j ACCEPT

			# amanda tape-backups; we reach out and tape things from this machine
			$IPTABLES -A INPUT -p udp -m state --state NEW --dport 10080 -j ACCEPT
			$IPTABLES -A INPUT -p tcp -m state --state NEW --dport 10082 -j ACCEPT
			$IPTABLES -A INPUT -p tcp -m state --state NEW --dport 10083 -j ACCEPT

	# nagios (5666); monitor time (123), allow snmp (161)		# nagios (5666); monitor time (123), allow snmp (161)

Gordp at 17:31, 30 January 2008

2008-01-30T17:31:50Z

← Older revision		Revision as of 17:31, 30 January 2008
Line 51:		Line 51:

	$IPTABLES -A OUTPUT -m state --state RELATED,ESTABLISHED -j ACCEPT		$IPTABLES -A OUTPUT -m state --state RELATED,ESTABLISHED -j ACCEPT

			Invoke and make these rules effective:
			<font color=red>hostname</font> <font color=blue>~ #</font> '''sh /etc/iptables.bak'''

			Resulting active rules:

			<font color=red>hostname</font> <font color=blue>~ #</font> '''iptables -L'''

			REMEMBER! If you like the ruleset, and want it to be in-effect the next time you start iptables (ie after a reboot), then you '''must''':
			<font color=red>hostname</font> <font color=blue>~ #</font> '''rc-update add iptables default'''
			<font color=lime>*</font> iptables added to runlevel default

			<font color=red>hostname</font> <font color=blue>~ #</font> '''/etc/init.d/iptables save'''
			<font color=lime>*</font> Saving iptables state ...

Gordp at 16:35, 30 January 2008

2008-01-30T16:35:39Z

New page

#! /bin/sh
# /etc/iptables.bak

# Let's save typing & confusion with variables
IPTABLES=/sbin/iptables

# Flush active rules and custom tables
$IPTABLES --flush
$IPTABLES --delete-chain

# set the defaults so that by-default incoming packets are dropped, unless explicitly allowed;
# for a desktop workstation, we'll let lots of (unpredictable) outgoing packets go freely.
$IPTABLES -P INPUT DROP
$IPTABLES -P FORWARD DROP
$IPTABLES -P OUTPUT ACCEPT

# INBOUND POLICY
# ==============
# of course, accepting loopback is a good idea
$IPTABLES -A INPUT -i lo -j ACCEPT

# (Applies to packets entering our network interface from the network,
# and addressed to this host.)

$IPTABLES -A INPUT -m state --state INVALID -j DROP
$IPTABLES -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT

# ftp incoming
$IPTABLES -A INPUT -p tcp -m state --state NEW --dport 20 -j ACCEPT
$IPTABLES -A INPUT -p tcp -m state --state NEW --dport 21 -j ACCEPT

# ssh incoming, including non-standard port (if needed)
$IPTABLES -A INPUT -p tcp -m state --state NEW --dport 22 -j ACCEPT
#$IPTABLES -A INPUT -p tcp -m state --state NEW --dport 222 -j ACCEPT

# web serving, let's allow it!
$IPTABLES -A INPUT -p tcp -m state --state NEW --dport 80 -j ACCEPT

# nagios (5666); monitor time (123), allow snmp (161)
$IPTABLES -A INPUT -p tcp -m state --state NEW --dport 5666 -j ACCEPT
$IPTABLES -A INPUT -p udp -m state --state NEW --dport 123 -j ACCEPT
$IPTABLES -A INPUT -p udp -m state --state NEW --dport 161 -j ACCEPT

# OUTBOUND POLICY
# ===============
# of course, accepting loopback is a good idea
$IPTABLES -A OUTPUT -o lo -j ACCEPT

# (Applies to packets sent to the network interface from local processes)

$IPTABLES -A OUTPUT -m state --state RELATED,ESTABLISHED -j ACCEPT