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NAME

Rex::Commands::Iptables - Iptable Management Commands

DESCRIPTION

With this Module you can manage basic Iptables rules.

Version <= 1.0: All these functions will not be reported.

Only open_port and close_port are idempotent.

SYNOPSIS

task "firewall", sub {
iptables_clear;
open_port 22;
open_port [22, 80] => {
dev => "eth0",
};
close_port 22 => {
dev => "eth0",
};
close_port "all";
redirect_port 80 => 10080;
redirect_port 80 => {
dev => "eth0",
to => 10080,
};
default_state_rule;
default_state_rule dev => "eth0";
is_nat_gateway;
iptables t => "nat",
A => "POSTROUTING",
o => "eth0",
j => "MASQUERADE";
# The 'iptables' function also accepts long options,
# however, options with dashes need to be quoted
iptables table => "nat",
accept => "POSTROUTING",
"out-interface" => "eth0",
jump => "MASQUERADE";
# Version of IP can be specified in the first argument
# of any function: -4 or -6 (defaults to -4)
iptables_clear -6;
open_port -6, [22, 80];
close_port -6, "all";
redirect_port -6, 80 => 10080;
default_state_rule -6;
iptables -6, "flush";
iptables -6,
t => "filter",
A => "INPUT",
i => "eth0",
m => "state",
state => "RELATED,ESTABLISHED",
j => "ACCEPT";
};

EXPORTED FUNCTIONS

open_port($port, $option)

Open a port for inbound connections.

task "firewall", sub {
open_port 22;
open_port [22, 80];
open_port [22, 80],
dev => "eth1";
};
task "firewall", sub {
open_port 22,
dev => "eth1",
only_if => "test -f /etc/firewall.managed";
} ;

close_port($port, $option)

Close a port for inbound connections.

task "firewall", sub {
close_port 22;
close_port [22, 80];
close_port [22, 80],
dev => "eth0",
only_if => "test -f /etc/firewall.managed";
};

redirect_port($in_port, $option)

Redirect $in_port to another local port.

task "redirects", sub {
redirect_port 80 => 10080;
redirect_port 80 => {
to => 10080,
dev => "eth0",
};
};

iptables(@params)

Write standard iptable comands.

Note that there is a short form for the iptables --flush option; when you pass the option of -F|"flush" as the only argument, the command iptables -F is run on the connected host. With the two argument form of flush shown in the examples below, the second argument is table you want to flush.

task "firewall", sub {
iptables t => "nat", A => "POSTROUTING", o => "eth0", j => "MASQUERADE";
iptables t => "filter", i => "eth0", m => "state", state => "RELATED,ESTABLISHED", j => "ACCEPT";
# automatically flushes all tables; equivalent to 'iptables -F'
iptables "flush";
iptables -F;
# flush only the "filter" table
iptables flush => "filter";
iptables -F => "filter";
};
# Note: options with dashes "-" need to be quoted to escape them from Perl
task "long_form_firewall", sub {
iptables table => "nat",
append => "POSTROUTING",
"out-interface" => "eth0",
jump => "MASQUERADE";
iptables table => "filter",
"in-interface" => "eth0",
match => "state",
state => "RELATED,ESTABLISHED",
jump => "ACCEPT";
};

is_nat_gateway

This function creates a NAT gateway for the device the default route points to.

task "make-gateway", sub {
is_nat_gateway;
is_nat_gateway -6;
};

default_state_rule(%option)

Set the default state rules for the given device.

task "firewall", sub {
default_state_rule(dev => "eth0");
};

iptables_list

List all iptables rules.

task "list-iptables", sub {
print Dumper iptables_list;
print Dumper iptables_list -6;
};

iptables_clear

Remove all iptables rules.

task "no-firewall", sub {
iptables_clear;
};