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<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
[
<!ENTITY authors SYSTEM "authors.xml">
<!ENTITY seealso SYSTEM "seealso.xml">
<!ENTITY notes SYSTEM "notes.xml">
]>

<!--
  SPDX-License-Identifier: GPL-2.0-or-later

  This file is part of firewalld.

  Copyright (C) 2010-2013 Red Hat, Inc.

  Authors:
  Thomas Woerner <twoerner@redhat.com>
-->

<refentry id="firewalld.helper">

  <refentryinfo>
    <title>firewalld.helper</title>
    <productname>firewalld</productname>
    &authors;
  </refentryinfo>

  <refmeta>
    <refentrytitle>firewalld.helper</refentrytitle>
    <manvolnum>5</manvolnum>
  </refmeta>

  <refnamediv>
    <refname>firewalld.helper</refname>
    <refpurpose>firewalld helper configuration files</refpurpose>
  </refnamediv>

  <refsynopsisdiv>
    <para>
      <programlisting>
<filename><config.sysconfdir/>/firewalld/helpers/helper.xml</filename>
<filename><config.prefix/>/lib/firewalld/helpers/helper.xml</filename>
      </programlisting>
    </para>
  </refsynopsisdiv>

  <refsect1 id="description">
    <title>Description</title>

    <para>
      A firewalld helper configuration file provides the information of a helper entry for firewalld. The most important configuration options are ports, family and module.
    </para>

    <para>
      This example configuration file shows the structure of a helper configuration file:

      <programlisting>
&lt;?xml version="1.0" encoding="utf-8"?&gt;
&lt;helper module="<replaceable>nf_conntrack_module</replaceable>" [family="<literal>ipv4</literal>|<literal>ipv6</literal>"]&gt;
  &lt;short&gt;<replaceable>short</replaceable>&lt;/short&gt;
  &lt;description&gt;<replaceable>description</replaceable>&lt;/description&gt;
  &lt;port <replaceable>portid</replaceable>[-<replaceable>portid</replaceable>]" protocol="<literal>tcp</literal>|<literal>udp</literal>|<literal>sctp</literal>|<literal>dccp</literal>"/&gt;
&lt;/helper&gt;
      </programlisting>
    </para>
  </refsect1>

  <refsect1 id="options">
    <title>Options</title>
    <para>
      The config can contain these tags and attributes. Some of them are mandatory, others optional.
    </para>

    <refsect2 id="options_helper">
      <title>helper</title>
      <para>
	The mandatory helper start and end tag defines the helper. This tag can only be used once in a helper configuration file. There is one mandatory and also optional attributes for helper:
      </para>

      <variablelist>
	<varlistentry>
          <term>module="<replaceable>string</replaceable>"</term>
          <listitem>
            <para>
              The mandatory module of the helper. This is one of the netfilter conntrack helper modules. The name starts with <literal>nf_conntrack_</literal>.
            </para>
          </listitem>
        </varlistentry>
	<varlistentry>
          <term>family="<literal>ipv4</literal>|<literal>ipv6</literal>"</term>
          <listitem>
            <para>
              The optional family of the helper. This can be one of these ipv types: <replaceable>ipv4</replaceable> or <replaceable>ipv6</replaceable>. If the family is not specified, then the helper is usable for <replaceable>IPv4</replaceable> and <replaceable>IPv6</replaceable>.
            </para>
          </listitem>
        </varlistentry>
	<varlistentry>
	  <term>version="<replaceable>string</replaceable>"</term>
          <listitem>
	    <para>
              To give the helper a version.
	    </para>
	  </listitem>
	</varlistentry>
      </variablelist>
    </refsect2>

    <refsect2 id="options_short">
      <title>short</title>
      <para>
        Is an optional start and end tag and is used to give a helper a more readable name.
      </para>
    </refsect2>

    <refsect2 id="options_description">
      <title>description</title>
      <para>
        Is an optional start and end tag to have a description for a helper.
      </para>
    </refsect2>

    <refsect2 id="options_port">
      <title>port</title>
      <para>
	Is an mandatory empty-element tag and can be used several times to have more than one port entry. All attributes of a port entry are mandatory:
      </para>

      <variablelist>
	<varlistentry>
	  <term>port="<replaceable>string</replaceable>"</term>
          <listitem>
	    <para>
	      The port <replaceable>string</replaceable> can be a single port number or a port range <replaceable>portid</replaceable>-<replaceable>portid</replaceable> or also empty to match a protocol only.
	    </para>
	  </listitem>
	</varlistentry>

	<varlistentry>
	  <term>protocol="<replaceable>string</replaceable>"</term>
          <listitem>
	    <para>
              The protocol value can either be <option>tcp</option>, <option>udp</option>, <option>sctp</option> or <option>dccp</option>.
	    </para>
	  </listitem>
	</varlistentry>
      </variablelist>
    </refsect2>

  </refsect1>

  &seealso;

  &notes;

</refentry>
