shorewall_code/Shorewall/manpages/shorewall-files.xml

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<refentry>
  <refmeta>
    <refentrytitle>shorewall-files</refentrytitle>

    <manvolnum>5</manvolnum>

    <refmiscinfo>Configuration Files</refmiscinfo>
  </refmeta>

  <refnamediv>
    <refname>files</refname>

    <refpurpose>Shorewall Configuration Files</refpurpose>
  </refnamediv>

  <refsynopsisdiv>
    <cmdsynopsis>
      <command>/etc/shorewall[6]/*</command>
    </cmdsynopsis>
  </refsynopsisdiv>

  <refsect1>
    <title>Description</title>

    <para>The following are the Shorewall[6] configuration files:</para>

    <itemizedlist>
      <listitem>
        <para><ulink
        url="shorewall.conf.html"><filename>/etc/shorewall/shorewall.conf</filename>
        and <filename>/etc/shorewall6/shorewall6.conf</filename></ulink> -
        used to set global firewall parameters.</para>
      </listitem>

      <listitem>
        <para><filename><ulink
        url="shorewall-params.html">/etc/shorewall[6]/params</ulink></filename>
        - use this file to set shell variables that you will expand in other
        files. It is always processed by /bin/sh or by the shell specified
        through SHOREWALL_SHELL in
        <filename>/etc/shorewall/shorewall.conf.</filename></para>
      </listitem>

      <listitem>
        <para><filename><ulink
        url="shorewall-zones.html">/etc/shorewall[6]/zones</ulink></filename>
        - partition the firewall's view of the world into zones.</para>
      </listitem>

      <listitem>
        <para><ulink
        url="shorewall-policy.html"><filename>/etc/shorewall[6]/policy</filename></ulink>
        - establishes firewall high-level policy.</para>
      </listitem>

      <listitem>
        <para><filename>/etc/shorewall[6]/initdone</filename> - An optional
        Perl script that will be invoked by the Shorewall rules compiler when
        the compiler has finished it's initialization.</para>
      </listitem>

      <listitem>
        <para><filename><ulink
        url="shorewall-interfaces.html">/etc/shorewall[6]/interfaces</ulink></filename>
        - describes the interfaces on the firewall system.</para>
      </listitem>

      <listitem>
        <para><filename><ulink
        url="shorewall-hosts.html">/etc/shorewall[6]/hosts</ulink></filename>
        - allows defining zones in terms of individual hosts and
        subnetworks.</para>
      </listitem>

      <listitem>
        <para><filename><ulink
        url="shorewall-masq.html">/etc/shorewall[6]/masq</ulink></filename> -
        directs the firewall where to use many-to-one (dynamic) Network
        Address Translation (a.k.a. Masquerading) and Source Network Address
        Translation (SNAT). Superseded by /etc/shorewall[6]/snat in Shorewall
        5.0.14 and not supported in Shorewall 5.1.0 and later versions.</para>
      </listitem>

      <listitem>
        <para><filename><ulink
        url="shorewall-mangle.html">/etc/shorewall[6]/mangle</ulink></filename>
        - supersedes <filename>/etc/shorewall/tcrules</filename> in Shorewall
        4.6.0. Contains rules for packet marking, TTL, TPROXY, etc.</para>
      </listitem>

      <listitem>
        <para><filename><ulink
        url="shorewall-rules.html">/etc/shorewall[6]/rules</ulink></filename>
        - defines rules that are exceptions to the overall policies
        established in /etc/shorewall/policy.</para>
      </listitem>

      <listitem>
        <para><filename><ulink
        url="shorewall-nat.html">/etc/shorewall[6]/nat</ulink></filename> -
        defines one-to-one NAT rules.</para>
      </listitem>

      <listitem>
        <para><filename><ulink
        url="shorewall-proxyarp.html">/etc/shorewall6/proxyarp</ulink></filename>
        - defines use of Proxy ARP.</para>
      </listitem>

      <listitem>
        <para><filename><ulink
        url="shorewall-proxyndp.html">/etc/shorewall6/proxyndp</ulink></filename>
        - defines use of Proxy NDP.</para>
      </listitem>

      <listitem>
        <para><filename>/etc/shorewall[6]/routestopped</filename> - defines
        hosts accessible when Shorewall is stopped. Superseded in Shorewall
        4.6.8 by <filename>/etc/shorewall/stoppedrules</filename>. Not
        supported in Shorewall 5.0.0 and later versions.</para>
      </listitem>

      <listitem>
        <para><filename><ulink
        url="shorewall-tcrules.html">/etc/shorewall[6]/tcrules</ulink>
        </filename>- The file has a rather unfortunate name because it is used
        to define marking of packets for later use by both traffic
        control/shaping and policy routing. This file is superseded by
        <filename>/etc/shorewall/mangle</filename> in Shorewall 4.6.0. Not
        supported in Shorewall 5.0.0 and later releases.</para>
      </listitem>

      <listitem>
        <para><filename><ulink
        url="shorewall-tos.html">/etc/shorewall[6]/tos</ulink></filename> -
        defines rules for setting the TOS field in packet headers. Superseded
        in Shorewall 4.5.1 by the TOS target in
        <filename>/etc/shorewall/tcrules</filename> (which file has since been
        superseded by <filename>/etc/shorewall/mangle</filename>). Not
        supported in Shorewall 5.0.0 and later versions.</para>
      </listitem>

      <listitem>
        <para><ulink
        url="shorewall-tunnels.html"><filename>/etc/shorewall[6]/tunnels</filename></ulink>
        - defines tunnels (VPN) with end-points on the firewall system.</para>
      </listitem>

      <listitem>
        <para><ulink
        url="shorewall-blacklist.html"><filename>/etc/shorewall[6]/blacklist</filename></ulink>
        - Deprecated in favor of <filename>/etc/shorewall/blrules</filename>.
        Lists blacklisted IP/subnet/MAC addresses. Not supported in Shorewall
        5.0.0 and later releases.</para>
      </listitem>

      <listitem>
        <para><filename>/etc/shorewall[6]/blrules</filename> — Added in
        Shorewall 4.5.0. Define blacklisting and whitelisting. Supersedes
        <filename>/etc/shorewall/blacklist</filename>.</para>
      </listitem>

      <listitem>
        <para><filename>/etc/shorewall[6]/init</filename> - shell commands
        that you wish to execute at the beginning of a <quote>shorewall
        start</quote>, "shorewall reload" or <quote>shorewall
        restart</quote>.</para>
      </listitem>

      <listitem>
        <para><filename>/etc/shorewall[6]/start</filename> - shell commands
        that you wish to execute near the completion of a <quote>shorewall
        start</quote>, "shorewall reload" or <quote>shorewall
        restart</quote></para>
      </listitem>

      <listitem>
        <para><filename>/etc/shorewall[6]/started</filename> - shell commands
        that you wish to execute after the completion of a <quote>shorewall
        start</quote>, "shorewall reload" or <quote>shorewall
        restart</quote></para>
      </listitem>

      <listitem>
        <para><filename>/etc/shorewall[6]/stop </filename>- commands that you
        wish to execute at the beginning of a <quote>shorewall
        stop</quote>.</para>
      </listitem>

      <listitem>
        <para><filename>/etc/shorewall[6]/stopped</filename> - shell commands
        that you wish to execute at the completion of a <quote>shorewall
        stop</quote>.</para>
      </listitem>

      <listitem>
        <para><ulink url="shorewall-ecn.html">/etc/shorewall/ecn</ulink> -
        disable Explicit Congestion Notification (ECN - RFC 3168) to remote
        hosts or networks. Superseded by ECN entries in
        <filename>/etc/shorewall/mangle</filename> in Shorewall 5.0.6.</para>
      </listitem>

      <listitem>
        <para><filename><ulink
        url="shorewall-accounting.html">/etc/shorewall/accounting</ulink></filename>
        - define IP traffic accounting rules</para>
      </listitem>

      <listitem>
        <para><filename><ulink
        url="shorewall-actions.html">/etc/shorewall[6]/actions</ulink></filename>
        and <filename>/usr/share/shorewall[6]/action.template</filename> allow
        user-defined actions.</para>
      </listitem>

      <listitem>
        <para><filename><ulink
        url="???">/etc/shorewall[6]/providers</ulink></filename> - defines
        alternate routing tables.</para>
      </listitem>

      <listitem>
        <para><filename><ulink
        url="shorewall-rtrules.html">/etc/shorewall[6]/rtrules</ulink></filename>
        - Defines routing rules to be used in conjunction with the routing
        tables defined in
        <filename>/etc/shorewall/providers</filename>.</para>
      </listitem>

      <listitem>
        <para><filename><ulink
        url="shorewall-tcdevices.html">/etc/shorewall[6]/tcdevices</ulink></filename>,
        <filename><ulink
        url="shorewall-tcclasses.html">/etc/shorewall[6]/tcclasses</ulink></filename>,
        <filename><ulink
        url="shorewall-tcfilters.html">/etc/shorewall[6]/tcfilters</ulink></filename>
        - Define complex traffic shaping.</para>
      </listitem>

      <listitem>
        <para><filename><ulink
        url="shorewall-tcrules.html">/etc/shorewall[6]/tcrules</ulink></filename>
        - Mark or classify traffic for traffic shaping or multiple providers.
        Deprecated in Shorewall 4.6.0 in favor of
        <filename>/etc/shorewall/mangle</filename>. Not supported in Shorewall
        5.0.0 and later releases.</para>
      </listitem>

      <listitem>
        <para><ulink
        url="shorewall-tcinterfaces.html"><filename>/etc/shorewall[6]/tcinterfaces</filename></ulink>
        and <filename><ulink
        url="shorewall-tcpri.html">/etc/shorewall[6]/tcpri</ulink></filename>
        - Define simple traffic shaping.</para>
      </listitem>

      <listitem>
        <para><filename><ulink
        url="shorewall-secmarks.html">/etc/shorewall[6]/secmarks</ulink></filename>
        - Added in Shorewall 4.4.13. Attach an SELinux context to selected
        packets.</para>
      </listitem>

      <listitem>
        <para><filename><ulink
        url="shorewall-vardir.html">/etc/shorewall[6]/vardir</ulink></filename>
        - Determines the directory where Shorewall maintains its state.</para>
      </listitem>

      <listitem>
        <para><filename><ulink
        url="shorewall-arprules.html">/etc/shorewall/arprules</ulink></filename>
        — Added in Shorewall 4.5.12. Allows specification of arptables
        rules.</para>
      </listitem>

      <listitem>
        <para><filename><ulink
        url="shorewall-mangle.html">/etc/shorewall/mangle</ulink></filename>
        -- Added in Shorewall 4.6.0. Supersedes<filename>
        /etc/shorewall/tcrules</filename>.</para>
      </listitem>

      <listitem>
        <para><filename><ulink
        url="shorewall-snat.html">/etc/shorewall[6]/snat</ulink></filename> -
        directs the firewall where to use many-to-one (dynamic) Network
        Address Translation (a.k.a. Masquerading) and Source Network Address
        Translation (SNAT). Superseded /etc/shorewall[6]/masq in Shorewall
        5.0.14</para>
      </listitem>

      <listitem>
        <para><filename>/usr/share/shorewall[6]/actions.std</filename> -
        Actions defined by Shorewall.</para>
      </listitem>

      <listitem>
        <para><filename>/usr/share/shorewall[6]/action.*</filename> - Details
        of actions defined by Shorewall.</para>
      </listitem>

      <listitem>
        <para><filename>/usr/share/shorewall[6]/macro.*</filename> - Details
        of macros defined by Shorewall.</para>
      </listitem>

      <listitem>
        <para><filename>/usr/share/shorewall[6]/modules</filename> — Specifies
        the kernel modules to be loaded during shorewall start/restart.</para>
      </listitem>

      <listitem>
        <para><filename>/usr/share/shorewall[6]/helpers</filename> — Added in
        Shorewall 4.4.7. Specifies the kernel modules to be loaded during
        shorewall start/restart when LOAD_HELPERS_ONLY=Yes in
        <filename>shorewall.conf</filename>.</para>
      </listitem>
    </itemizedlist>
  </refsect1>

  <refsect1>
    <title>CONFIG_PATH</title>

    <para>The CONFIG_PATH option in <ulink
    url="???">shorewall[6].conf(5)</ulink> determines where the compiler
    searches for configuration files. The default setting is
    CONFIG_PATH=/etc/shorewall:/usr/share/shorewall which means that the
    compiler first looks in /etc/shorewall and if it doesn't find the file, it
    then looks in /usr/share/shorewall.</para>

    <para>You can change this setting to have the compiler look in different
    places. For example, if you want to put your own versions of standard
    macros in /etc/shorewall/Macros, then you could set
    CONFIG_PATH=/etc/shorewall:/etc/shorewall/Macros:/usr/share/shorewall and
    the compiler will use your versions rather than the standard ones.</para>
  </refsect1>

  <refsect1>
    <title>Comments</title>

    <para>You may place comments in configuration files by making the first
    non-whitespace character a pound sign (<quote>#</quote>). You may also
    place comments at the end of any line, again by delimiting the comment
    from the rest of the line with a pound sign.</para>

    <example id="comment">
      <title>Comments in a Configuration File</title>

      <programlisting># This is a comment
ACCEPT  net     $FW      tcp     www     #This is an end-of-line comment</programlisting>
    </example>

    <important>
      <para>Except in <ulink
      url="shorewall.conf.html">shorewall.conf(5)</ulink> and <ulink
      url="shorewall-params.html">params(5)</ulink>, if a comment ends with a
      backslash ("\"), the next line will also be treated as a comment. See
      <link linkend="Continuation">Line Continuation</link> below.</para>
    </important>
  </refsect1>

  <refsect1>
    <title>Blank Lines</title>

    <para>Most of the configuration files are organized into space-separated
    columns. If you don't want to supply a value in a column but want to
    supply a value in a following column, simply enter '-' to make the column
    appear empty.</para>

    <para>Example:<programlisting>#INTERFACE         BROADCAST            OPTIONS
br0                -                    routeback</programlisting></para>
  </refsect1>

  <refsect1>
    <title id="Continuation">Line Continuation</title>

    <para>Lines may be continued using the usual backslash (<quote>\</quote>)
    followed immediately by a new line character (Enter key).</para>

    <programlisting>ACCEPT  net     $FW      tcp \↵
smtp,www,pop3,imap  #Services running on the firewall</programlisting>

    <important>
      <para>What follows does NOT apply to <ulink
      url="manpages/shorewall-params.html">shorewall-params(5)</ulink> and
      <ulink url="shorewall.conf.html">shorewall.conf(5)</ulink>.</para>
    </important>

    <para>In certain cases, leading white space is ignored in continuation
    lines:</para>

    <orderedlist>
      <listitem>
        <para>The continued line ends with a colon (":")</para>
      </listitem>

      <listitem>
        <para>The continued line ends with a comma (",")</para>
      </listitem>
    </orderedlist>

    <para>Example (<filename>/etc/shorewall/rules</filename>):</para>

    <programlisting>#ACTION     SOURCE          DEST            PROTO           DPORT
ACCEPT      net:\
            206.124.146.177,\
            206.124.146.178,\
            206.124.146.180\
                            dmz             tcp             873</programlisting>

    <para>The leading white space on the first through third continuation
    lines is ignored so the SOURCE column effectively contains
    "net:206.124.146.177,206.124.147.178,206.124.146.180". Because the third
    continuation line does not end with a comma or colon, the leading white
    space in the last line is not ignored.</para>

    <important>
      <para>A trailing backslash is not ignored in a comment. So the continued
      rule above can be commented out with a single '#' as follows:</para>

      <programlisting>#ACTION     SOURCE          DEST            PROTO           DPORT
<emphasis role="bold">#</emphasis>ACCEPT     net:\
            206.124.146.177,\
            206.124.146.178,\
            206.124.146.180\
                            dmz             tcp             873</programlisting>
    </important>
  </refsect1>

  <refsect1>
    <title>Alternative Specification of Column Values</title>

    <para>Some of the configuration files now have a large number of columns.
    That makes it awkward to specify a value for one of the right-most columns
    as you must have the correct number of intervening '-' columns.</para>

    <para>This problem is addressed by allowing column values to be specified
    as <replaceable>column-name</replaceable>/<replaceable>value</replaceable>
    pairs.</para>

    <para>There is considerable flexibility in how you specify the
    pairs:</para>

    <itemizedlist>
      <listitem>
        <para>At any point, you can enter a left curly bracket ('{') followed
        by one or more specifications of the following forms:</para>

        <simplelist>
          <member><replaceable>column-name</replaceable>=<replaceable>value</replaceable></member>

          <member><replaceable>column-name</replaceable>=<replaceable>&gt;value</replaceable></member>

          <member><replaceable>column-name</replaceable>:<replaceable>value</replaceable></member>
        </simplelist>

        <para>The pairs must be followed by a right curly bracket
        ("}").</para>

        <para>The value may optionally be enclosed in double quotes.</para>

        <para>The pairs must be separated by white space, but you can add a
        comma adjacent to the <replaceable>values</replaceable> for
        readability as in:</para>

        <simplelist>
          <member><emphasis role="bold">{ proto=&gt;udp, port=1024
          }</emphasis></member>
        </simplelist>
      </listitem>

      <listitem>
        <para>You can also separate the pairs from columns by using a
        semicolon:</para>

        <simplelist>
          <member><emphasis role="bold">; proto:udp,
          port:1024</emphasis></member>
        </simplelist>
      </listitem>
    </itemizedlist>

    <para>In Shorewall 5.0.3, the sample configuration files and the man pages
    were updated to use the same column names in both the column headings and
    in the alternate specification format. The following table shows the
    column names for each of the table-oriented configuration files.</para>

    <note>
      <para>Column names are <emphasis
      role="bold">case-insensitive</emphasis>.</para>
    </note>

    <informaltable>
      <tgroup cols="2">
        <tbody>
          <row>
            <entry><emphasis role="bold">File</emphasis></entry>

            <entry><emphasis role="bold">Column names</emphasis></entry>
          </row>

          <row>
            <entry>accounting</entry>

            <entry>action,chain, source, dest, proto, dport, sport, user,
            mark, ipsec, headers</entry>
          </row>

          <row>
            <entry>conntrack</entry>

            <entry>action,source,dest,proto,dport,sport,user,switch</entry>
          </row>

          <row>
            <entry>blacklist</entry>

            <entry>networks,proto,port,options</entry>
          </row>

          <row>
            <entry>blrules</entry>

            <entry>action,source,dest,proto,dport,sport,origdest,rate,user,mark,connlimit,time,headers,switch,helper</entry>
          </row>

          <row>
            <entry>ecn</entry>

            <entry>interface,hosts. Beginning with Shorewall 4.5.4, 'host' is
            a synonym for 'hosts'.</entry>
          </row>

          <row>
            <entry>hosts</entry>

            <entry>zone,hosts,options. Beginning with Shorewall 4.5.4, 'host'
            is a synonym for 'hosts'.</entry>
          </row>

          <row>
            <entry>interfaces</entry>

            <entry>zone,interface,broadcast,options</entry>
          </row>

          <row>
            <entry>maclist</entry>

            <entry>disposition,interface,mac,addresses</entry>
          </row>

          <row>
            <entry>mangle</entry>

            <entry>action,source,dest,proto,dport,sport,user,test,length,tos,connbytes,helper,headers</entry>
          </row>

          <row>
            <entry>masq</entry>

            <entry>interface,source,address,proto,port,ipsec,mark,user,switch</entry>
          </row>

          <row>
            <entry>nat</entry>

            <entry>external,interface,internal,allints,local</entry>
          </row>

          <row>
            <entry>netmap</entry>

            <entry>type,net1,interface,net2,net3,proto,dport,sport</entry>
          </row>

          <row>
            <entry>notrack</entry>

            <entry>source,dest,proto,dport,sport,user</entry>
          </row>

          <row>
            <entry>policy</entry>

            <entry>source,dest,policy,loglevel,limit,connlimit</entry>
          </row>

          <row>
            <entry>providers</entry>

            <entry>table,number,mark,duplicate,interface,gateway,options,copy</entry>
          </row>

          <row>
            <entry>proxyarp and proxyndp</entry>

            <entry>address,interface,external,haveroute,persistent</entry>
          </row>

          <row>
            <entry>rtrules</entry>

            <entry>source,dest,provider,priority</entry>
          </row>

          <row>
            <entry>routes</entry>

            <entry>provider,dest,gateway,device</entry>
          </row>

          <row>
            <entry>routestopped</entry>

            <entry>interface,hosts,options,proto,dport,sport</entry>
          </row>

          <row>
            <entry>rules</entry>

            <entry>action,source,dest,proto,dport,sport,origdest,rate,user,mark,connlimit,time,headers,switch,helper</entry>
          </row>

          <row>
            <entry>secmarks</entry>

            <entry>secmark,chain,source,dest,proto,dport,sport,user,mark</entry>
          </row>

          <row>
            <entry>tcclasses</entry>

            <entry>interface,mark,rate,ceil,prio,options</entry>
          </row>

          <row>
            <entry>tcdevices</entry>

            <entry>interface,in_bandwidth,out_bandwidth,options,redirect</entry>
          </row>

          <row>
            <entry>tcfilters</entry>

            <entry>class,source,dest,proto,dport,sport,tos,length</entry>
          </row>

          <row>
            <entry>tcinterfaces</entry>

            <entry>interface,type,in_bandwidth,out_bandwidth</entry>
          </row>

          <row>
            <entry>tcpri</entry>

            <entry>band,proto,port,address,interface,helper</entry>
          </row>

          <row>
            <entry>tcrules</entry>

            <entry>mark,source,dest,proto,dport,sport,user,test,length,tos,connbytes,helper,headers.
            Beginning with Shorewall 4.5.3, 'action' is a synonym for
            'mark'.</entry>
          </row>

          <row>
            <entry>tos</entry>

            <entry>source,dest,proto,dport,sport,tos,mark</entry>
          </row>

          <row>
            <entry>tunnels</entry>

            <entry>type,zone,gateway,gateway_zone. Beginning with Shorewall
            4.5.3, 'gateways' is a synonym for 'gateway'. Beginning with
            Shorewall 4.5.4, 'gateway_zones' is a synonym for
            'gateway_zone'.</entry>
          </row>

          <row>
            <entry>zones</entry>

            <entry>zone,type,options,in_options,out_options</entry>
          </row>
        </tbody>
      </tgroup>
    </informaltable>

    <para>Example (rules file):</para>

    <programlisting>#ACTION         SOURCE            DEST            PROTO   DPORT
DNAT            net               loc:10.0.0.1    tcp     80    ; mark="88"</programlisting>

    <para>Here's the same line in several equivalent formats:</para>

    <programlisting>{ action=&gt;DNAT, source=&gt;net, dest=&gt;loc:10.0.0.1, proto=&gt;tcp, dport=&gt;80, mark=&gt;88 }
; action:"DNAT" source:"net"  dest:"loc:10.0.0.1" proto:"tcp" dport:"80" mark:"88"
DNAT { source=net dest=loc:10.0.0.1 proto=tcp dport=80 mark=88 }</programlisting>

    <para>Beginning with Shorewall 5.0.11, ip[6]table comments can be attached
    to individual rules using the <option>comment</option> keyword.</para>

    <para>Example from the rules file:</para>

    <programlisting>        ACCEPT net $FW { proto=tcp, dport=22, comment="Accept \"SSH\"" }</programlisting>

    <para>As shown in that example, when the comment contains whitespace, it
    must be enclosed in double quotes and any embedded double quotes must be
    escaped using a backslash ("\").</para>
  </refsect1>

  <refsect1>
    <title>Time Columns</title>

    <para>Several of the files include a TIME column that allows you to
    specify times when the rule is to be applied. Contents of this column is a
    list of <replaceable>timeelement</replaceable>s separated by apersands
    (&amp;).</para>

    <para>Each <replaceable>timeelement</replaceable> is one of the
    following:</para>

    <variablelist>
      <varlistentry>
        <term>timestart=<replaceable>hh</replaceable>:<replaceable>mm</replaceable>[:<replaceable>ss</replaceable>]</term>

        <listitem>
          <para>Defines the starting time of day.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>timestop=<replaceable>hh</replaceable>:<replaceable>mm</replaceable>[:<replaceable>ss</replaceable>]</term>

        <listitem>
          <para>Defines the ending time of day.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>contiguous</term>

        <listitem>
          <para>Added in Shoreawll 5.0.12. When <emphasis
          role="bold">timestop</emphasis> is smaller than <emphasis
          role="bold">timestart</emphasis> value, match this as a single time
          period instead of distinct intervals. See the Examples below.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>utc</term>

        <listitem>
          <para>Times are expressed in Greenwich Mean Time.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>localtz</term>

        <listitem>
          <para>Deprecated by the Netfilter team in favor of <emphasis
          role="bold">kerneltz</emphasis>. Times are expressed in Local Civil
          Time (default).</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>kerneltz</term>

        <listitem>
          <para>Added in Shorewall 4.5.2. Times are expressed in Local Kernel
          Time (requires iptables 1.4.12 or later).</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>weekdays=ddd[,ddd]...</term>

        <listitem>
          <para>where <replaceable>ddd</replaceable> is one of
          <option>Mon</option>, <option>Tue</option>, <option>Wed</option>,
          <option>Thu</option>, <option>Fri</option>, <option>Sat</option> or
          <option>Sun</option></para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>monthdays=dd[,dd],...</term>

        <listitem>
          <para>where <replaceable>dd</replaceable> is an ordinal day of the
          month</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>datestart=<replaceable>yyyy</replaceable>[-<replaceable>mm</replaceable>[-<replaceable>dd</replaceable>[<option>T</option><replaceable>hh</replaceable>[:<replaceable>mm</replaceable>[:<replaceable>ss</replaceable>]]]]]</term>

        <listitem>
          <para>Defines the starting date and time.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>datestop=<replaceable>yyyy</replaceable>[-<replaceable>mm</replaceable>[-<replaceable>dd</replaceable>[<option>T</option><replaceable>hh</replaceable>[:<replaceable>mm</replaceable>[:<replaceable>ss</replaceable>]]]]]</term>

        <listitem>
          <para>Defines the ending date and time.</para>
        </listitem>
      </varlistentry>
    </variablelist>

    <para>Examples:</para>

    <variablelist>
      <varlistentry>
        <term>To match on weekends, use:</term>

        <listitem>
          <para/>

          <para>weekdays=Sat,Sun</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>Or, to match (once) on a national holiday block:</term>

        <listitem>
          <para/>

          <para>datestart=2016-12-24&amp;datestop=2016-12-27</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>Since the stop time is actually inclusive, you would need the
        following stop time to not match the first second of the new
        day:</term>

        <listitem>
          <para/>

          <para>datestart=2016-12-24T17:00&amp;datestop=2016-12-27T23:59:59</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>During Lunch Hour</term>

        <listitem>
          <para/>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>The fourth Friday in the month:</term>

        <listitem>
          <para/>

          <para>weekdays=Fri&amp;monthdays=22,23,24,25,26,27,28</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>Matching across days might not do what is expected. For
        instance,</term>

        <listitem>
          <para/>

          <para>weekdays=Mon&amp;timestart=23:00&amp;timestop=01:00</para>

          <para>Will match Monday, for one hour from midnight to 1 a.m., and
          then again for another hour from 23:00 onwards. If this is unwanted,
          e.g. if you would like 'match for two hours from Montay 23:00
          onwards' you need to also specify the <emphasis
          role="bold">contiguous</emphasis> option in the example
          above.</para>
        </listitem>
      </varlistentry>
    </variablelist>
  </refsect1>

  <refsect1>
    <title>Switches</title>

    <para>here are times when you would like to enable or disable one or more
    rules in the configuration without having to do a <command>shorewall
    reload</command> or <command>shorewall restart</command>. This may be
    accomplished using the SWITCH column in <ulink
    url="manpages/shorewall-rules.html">shorewall-rules</ulink> (5) or <ulink
    url="manpages/shorewall-rules.html">shorewall6-rules</ulink> (5). Using
    this column requires that your kernel and iptables include
    <firstterm>Condition Match Support</firstterm> and you must be running
    Shorewall 4.4.24 or later. See the output of <command>shorewall show
    capabilities</command> and <command>shorewall version</command> to
    determine if you can use this feature.</para>

    <para>The SWITCH column contains the name of a
    <firstterm>switch.</firstterm> Each switch is initially in the <emphasis
    role="bold">off</emphasis> position. You can turn on the switch named
    <emphasis>switch1</emphasis> by:</para>

    <simplelist>
      <member><command>echo 1 &gt;
      /proc/net/nf_condition/switch1</command></member>
    </simplelist>

    <para>You can turn it off again by:</para>

    <simplelist>
      <member><command>echo 0 &gt;
      /proc/net/nf_condition/switch1</command></member>
    </simplelist>

    <para>If you simply include the switch name in the SWITCH column, then the
    rule is enabled only when the switch is <emphasis
    role="bold">on</emphasis>. If you precede the switch name with ! (e.g.,
    !switch1), then the rule is enabled only when the switch is <emphasis
    role="bold">off</emphasis>. Switch settings are retained over
    <command>shorewall reload</command>.</para>

    <para>Shorewall requires that switch names:</para>

    <itemizedlist>
      <listitem>
        <para>begin with a letter and be composed of letters, digits,
        underscore ('_') or hyphen ('-'); and</para>
      </listitem>

      <listitem>
        <para>be 30 characters or less in length.</para>
      </listitem>
    </itemizedlist>

    <para>Multiple rules can be controlled by the same switch.</para>

    <para>Example:</para>

    <blockquote>
      <para>Forward port 80 to dmz host $BACKUP if switch 'primary_down' is
      on.</para>

      <programlisting>#ACTION     SOURCE          DEST        PROTO       DPORT        SPORT     ORIGDEST   RATE      USER      MARK    CONNLIMIT     TIME     HEADERS    SWITCH
DNAT        net             dmz:$BACKUP tcp         80           -         -          -         -         -       -             -        -          <emphasis
          role="bold">primary_down</emphasis>  </programlisting>
    </blockquote>
  </refsect1>

  <refsect1>
    <title>FILES</title>

    <para>/etc/shorewall[6]/*</para>
  </refsect1>
</refentry>