Reference

Rex::Commands::Iptables(3pm)

Iptable Management Commands

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

 use Rex::Commands::Iptables;
 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;
 };

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