shorewall_code/manpages/shorewall-tcrules.xml

<?xml version="1.0" encoding="UTF-8"?>
<refentry>
  <refmeta>
    <refentrytitle>shorewall-tcrules</refentrytitle>

    <manvolnum>5</manvolnum>
  </refmeta>

  <refnamediv>
    <refname>tcrules</refname>

    <refpurpose>Shorewall Packet Marking rules file</refpurpose>
  </refnamediv>

  <refsynopsisdiv>
    <cmdsynopsis>
      <command>/etc/shorewall/</command>
    </cmdsynopsis>
  </refsynopsisdiv>

  <refsect1>
    <title>Description</title>

    <para>Entries in this file cause packets to be marked as a means of
    classifying them for traffic control or policy routing.</para>

    <important>
      <para>Unlike rules in the <ulink
      url="shorewall-rules.html">shorewall-rules</ulink>(5) file, evaluation
      of rules in this file will continue after a match. So the final mark for
      each packet will be the one assigned by the LAST tcrule that
      matches.</para>

      <para>If you use multiple internet providers with the 'track' option, in
      /etc/shorewall/providers be sure to read the restrictions at <ulink
      url="http://shorewall.net/MultiISP.html">http://shorewall.net/MultiISP.html</ulink>.</para>
    </important>

    <para>The columns in the file are as follows.</para>

    <variablelist>
      <varlistentry>
        <term><emphasis role="bold">MARK/CLASSIFY</emphasis> —
        {<emphasis>value</emphasis>|<emphasis>major</emphasis><emphasis
        role="bold">:</emphasis><emphasis>minor</emphasis>|<emphasis
        role="bold">RESTORE</emphasis>[<emphasis
        role="bold">/</emphasis><emphasis>mask</emphasis>]|<emphasis
        role="bold">SAVE</emphasis>[<emphasis
        role="bold">/</emphasis><emphasis>mask</emphasis>]|<emphasis
        role="bold">CONTINUE</emphasis>|<emphasis
        role="bold">COMMENT</emphasis>}[<emphasis
        role="bold">:</emphasis>{<emphasis role="bold">C</emphasis>|<emphasis
        role="bold">F</emphasis>|<emphasis role="bold">P</emphasis>|<emphasis
        role="bold">T</emphasis>|<emphasis role="bold">CF</emphasis>|<emphasis
        role="bold">CP</emphasis>|<emphasis role="bold">CT</emphasis>}]</term>

        <listitem>
          <orderedlist numeration="arabic">
            <listitem>
              <para>A mark <emphasis>value</emphasis> which is an integer in
              the range 1-255.</para>

              <para>Normally will set the mark value. If preceded by a
              vertical bar ("|"), the mark value will be logically ORed with
              the current mark value to produce a new mark value. If preceded
              by an ampersand ("&amp;"), will be logically ANDed with the
              current mark value to produce a new mark value.</para>

              <para>Both "|" and "&amp;" require Extended MARK Target support
              in your kernel and iptables; neither may be used with connection
              marks (see below).</para>

              <para>If HIGH_ROUTE_MARKS=Yes in <ulink
              url="shorewall.conf.html">shorewall.conf</ulink>(5) then you may
              also specify a value in the range 0x0100-0xFF00 with the
              low-order byte being zero. Such values may only be used in the
              PREROUTING chain(value followed by <emphasis
              role="bold">:F</emphasis> or you have set
              MARK_IN_FORWARD_CHAIN=Yes in <ulink
              url="shorewall.conf.html">shorewall.conf</ulink>(5) and have not
              followed the value with :P) or the OUTPUT chain (SOURCE is
              <emphasis role="bold">$FW</emphasis>).</para>

              <para>May optionally be followed by <emphasis
              role="bold">:P</emphasis>, <emphasis role="bold">:F</emphasis>
              or <emphasis role="bold">:T</emphasis> where<emphasis
              role="bold"> :P</emphasis> indicates that marking should occur
              in the PREROUTING chain, <emphasis role="bold">:F</emphasis>
              indicates that marking should occur in the FORWARD chain and
              <emphasis role="bold">:T</emphasis> indicates that marking
              should occur in the POSTROUTING chain. If neither <emphasis
              role="bold">:P</emphasis>, <emphasis role="bold">:F</emphasis>
              nor <emphasis role="bold">:T</emphasis> follow the mark value
              then the chain is determined as follows:</para>

              <itemizedlist>
                <listitem>
                  <para>If the SOURCE is <emphasis
                  role="bold">$FW</emphasis>[<emphasis
                  role="bold">:</emphasis><emphasis>address-or-range</emphasis>[,<emphasis>address-or-range</emphasis>]...],
                  then the rule is inserted into the OUTPUT chain.</para>
                </listitem>

                <listitem>
                  <para>Otherwise, the chain is determined by the setting of
                  MARK_IN_FORWARD_CHAIN in <ulink
                  url="shorewall.conf.html">shorewall.conf</ulink>(5).</para>
                </listitem>
              </itemizedlist>

              <para>If your kernel and iptables include CONNMARK support then
              you can also mark the connection rather than the packet.</para>

              <para>The mark value may be optionally followed by "/" and a
              mask value (used to determine those bits of the connection mark
              to actually be set). The mark and optional mask are then
              followed by one of:+</para>

              <variablelist>
                <varlistentry>
                  <term><emphasis role="bold">C</emphasis></term>

                  <listitem>
                    <para>Mark the connection in the chain determined by the
                    setting of MARK_IN_FORWARD_CHAIN</para>
                  </listitem>
                </varlistentry>

                <varlistentry>
                  <term><emphasis role="bold">CF</emphasis></term>

                  <listitem>
                    <para>Mark the connection in the FORWARD chain</para>
                  </listitem>
                </varlistentry>

                <varlistentry>
                  <term><emphasis role="bold">CP</emphasis></term>

                  <listitem>
                    <para>Mark the connection in the PREROUTING chain.</para>
                  </listitem>
                </varlistentry>

                <varlistentry>
                  <term>CT</term>

                  <listitem>
                    <para>Mark the connecdtion in the POSTROUTING chain</para>
                  </listitem>
                </varlistentry>
              </variablelist>
            </listitem>

            <listitem>
              <para>A classification (classid) of the form
              <emphasis>major</emphasis>:<emphasis>minor</emphasis> where
              <emphasis>major</emphasis> and <emphasis>minor</emphasis> are
              integers. Corresponds to the 'class' specification in these
              traffic shaping modules:</para>

              <programlisting>       atm
       cbq
       dsmark
       pfifo_fast
       htb
       prio</programlisting>

              <para>Classification occurs in the POSTROUTING chain except when
              the <emphasis role="bold">SOURCE</emphasis> is <emphasis
              role="bold">$FW</emphasis>[:<emphasis>address</emphasis>] in
              which case marking occurs in the OUTPUT chain.</para>

              <para>When using Shorewall's built-in traffic tool, the
              <emphasis>major</emphasis> class is the device number (the first
              device in <ulink
              url="shorewall-tcdevices.html">shorewall-tcdevices</ulink>(5) is
              major class 1, the second device is major class 2, and so on)
              and the <emphasis>minor</emphasis> class is the class's MARK
              value in <ulink
              url="shorewall-tcclasses.html">shorewall-tcclasses</ulink>(5)
              preceded by the number 1 (MARK 1 corresponds to minor class 11,
              MARK 5 corresponds to minor class 15, MARK 22 corresponds to
              minor class 122, etc.).</para>
            </listitem>

            <listitem>
              <para><emphasis
              role="bold">RESTORE</emphasis>[/<emphasis>mask</emphasis>] --
              restore the packet's mark from the connection's mark using the
              supplied mask if any. Your kernel and iptables must include
              CONNMARK support.</para>

              <para>As in 1) above, may be followed by <emphasis
              role="bold">:P</emphasis> or <emphasis
              role="bold">:F</emphasis></para>
            </listitem>

            <listitem>
              <para><emphasis
              role="bold">SAVE</emphasis>[/<emphasis>mask</emphasis>] -- save
              the packet's mark to the connection's mark using the supplied
              mask if any. Your kernel and iptables must include CONNMARK
              support.</para>

              <para>As in 1) above, may be followed by <emphasis
              role="bold">:P</emphasis> or <emphasis
              role="bold">:F</emphasis></para>
            </listitem>

            <listitem>
              <para><emphasis role="bold">CONTINUE</emphasis> Don't process
              any more marking rules in the table.</para>

              <para>As in 1) above, may be followed by <emphasis
              role="bold">:P</emphasis> or <emphasis
              role="bold">:F</emphasis>. Currently, CONTINUE may not be used
              with <emphasis>exclusion</emphasis> (see the SOURCE and DEST
              columns below); that restriction will be removed when
              iptables/Netfilter provides the necessary support.</para>
            </listitem>

            <listitem>
              <para><emphasis role="bold">COMMENT</emphasis> -- the rest of
              the line will be attached as a comment to the Netfilter rule(s)
              generated by the following entries. The comment will appear
              delimited by "/* ... */" in the output of <command>shorewall
              show mangle</command></para>

              <para>To stop the comment from being attached to further rules,
              simply include COMMENT on a line by itself.</para>
            </listitem>
          </orderedlist>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term><emphasis role="bold">SOURCE</emphasis> — {<emphasis
        role="bold">-</emphasis>|{<emphasis>interface</emphasis>|<emphasis
        role="bold">$FW</emphasis>}|[{<emphasis>interface</emphasis>|<emphasis
        role="bold">$FW</emphasis>}:]<emphasis>address-or-range</emphasis>[<emphasis
        role="bold">,</emphasis><emphasis>address-or-range</emphasis>]...}[<emphasis>exclusion</emphasis>]</term>

        <listitem>
          <para>Source of the packet. A comma-separated list of interface
          names, IP addresses, MAC addresses and/or subnets for packets being
          routed through a common path. List elements may also consist of an
          interface name followed by ":" and an address (e.g.,
          eth1:192.168.1.0/24). For example, all packets for connections
          masqueraded to eth0 from other interfaces can be matched in a single
          rule with several alternative SOURCE criteria. However, a connection
          whose packets gets to eth0 in a different way, e.g., direct from the
          firewall itself, needs a different rule.</para>

          <para>Accordingly, use $<emphasis role="bold">FW</emphasis> in its
          own separate rule for packets originating on the firewall. In such a
          rule, the MARK column may NOT specify either <emphasis
          role="bold">:P</emphasis> or <emphasis role="bold">:F</emphasis>
          because marking for firewall-originated packets always occurs in the
          OUTPUT chain.</para>

          <para>MAC addresses must be prefixed with "~" and use "-" as a
          separator.</para>

          <para>Example: ~00-A0-C9-15-39-78</para>

          <para>You may exclude certain hosts from the set already defined
          through use of an <emphasis>exclusion</emphasis> (see <ulink
          url="shorewall-exclusion.html">shorewall-exclusion</ulink>(5)).</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term><emphasis role="bold">DEST</emphasis> — {<emphasis
        role="bold">-</emphasis>|{<emphasis>interface</emphasis>|[<emphasis>interface</emphasis>:]<emphasis>address-or-range</emphasis>[<emphasis
        role="bold">,</emphasis><emphasis>address-or-range</emphasis>]...}[<emphasis>exclusion</emphasis>]</term>

        <listitem>
          <para>Destination of the packet. Comma separated list of IP
          addresses and/or subnets. If your kernel and iptables include
          iprange match support, IP address ranges are also allowed. List
          elements may also consist of an interface name followed by ":" and
          an address (e.g., eth1:192.168.1.0/24). If the <emphasis
          role="bold">MARK</emphasis> column specificies a classification of
          the form <emphasis>major</emphasis>:<emphasis>minor</emphasis> then
          this column may also contain an interface name.</para>

          <para>You may exclude certain hosts from the set already defined
          through use of an <emphasis>exclusion</emphasis> (see <ulink
          url="shorewall-exclusion.html">shorewall-exclusion</ulink>(5)).</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term><emphasis role="bold">PROTO</emphasis> — {<emphasis
        role="bold">-</emphasis>|<emphasis
        role="bold">tcp:syn</emphasis>|<emphasis
        role="bold">ipp2p</emphasis>|<emphasis
        role="bold">ipp2p:udp</emphasis>|<emphasis
        role="bold">ipp2p:all</emphasis>|<emphasis>protocol-number</emphasis>|<emphasis>protocol-name</emphasis>|<emphasis
        role="bold">all}</emphasis></term>

        <listitem>
          <para>Protocol - <emphasis role="bold">ipp2p</emphasis> requires
          ipp2p match support in your kernel and iptables.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term><emphasis role="bold">PORT(S)</emphasis> (Optional) — [<emphasis
        role="bold">-</emphasis>|<emphasis>port-name-number-or-range</emphasis>[<emphasis
        role="bold">,</emphasis><emphasis>port-name-number-or-range</emphasis>]...]</term>

        <listitem>
          <para>Destination Ports. A comma-separated list of Port names (from
          services(5)), <emphasis>port number</emphasis>s or <emphasis>port
          range</emphasis>s; if the protocol is <emphasis
          role="bold">icmp</emphasis>, this column is interpreted as the
          destination icmp-type(s).</para>

          <para>If the protocol is <emphasis role="bold">ipp2p</emphasis>,
          this column is interpreted as an ipp2p option without the leading
          "--" (example <emphasis role="bold">bit</emphasis> for bit-torrent).
          If no PORT is given, <emphasis role="bold">ipp2p</emphasis> is
          assumed.</para>

          <para>This column is ignored if PROTOCOL = all but must be entered
          if any of the following field is supplied. In that case, it is
          suggested that this field contain "-"</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term><emphasis role="bold">SOURCE PORT(S)</emphasis> (Optional) —
        [<emphasis
        role="bold">-</emphasis>|<emphasis>port-name-number-or-range</emphasis>[<emphasis
        role="bold">,</emphasis><emphasis>port-name-number-or-range</emphasis>]...]</term>

        <listitem>
          <para>Source port(s). If omitted, any source port is acceptable.
          Specified as a comma-separated list of port names, port numbers or
          port ranges.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term><emphasis role="bold">USER</emphasis> (Optional) — [<emphasis
        role="bold">!</emphasis>][<emphasis>user-name-or-number</emphasis>][<emphasis
        role="bold">:</emphasis><emphasis>group-name-or-number</emphasis>][<emphasis
        role="bold">+</emphasis><emphasis>program-name</emphasis>]</term>

        <listitem>
          <para>This column may only be non-empty if the SOURCE is the
          firewall itself.</para>

          <para>When this column is non-empty, the rule applies only if the
          program generating the output is running under the effective
          <emphasis>user</emphasis> and/or <emphasis>group</emphasis>
          specified (or is NOT running under that id if "!" is given).</para>

          <para>Examples:</para>

          <variablelist>
            <varlistentry>
              <term>joe</term>

              <listitem>
                <para>program must be run by joe</para>
              </listitem>
            </varlistentry>

            <varlistentry>
              <term>:kids</term>

              <listitem>
                <para>program must be run by a member of the 'kids'
                group</para>
              </listitem>
            </varlistentry>

            <varlistentry>
              <term>!:kids</term>

              <listitem>
                <para>program must not be run by a member of the 'kids'
                group</para>
              </listitem>
            </varlistentry>

            <varlistentry>
              <term>+upnpd</term>

              <listitem>
                <para>#program named upnpd</para>

                <important>
                  <para>The ability to specify a program name was removed from
                  Netfilter in kernel version 2.6.14.</para>
                </important>
              </listitem>
            </varlistentry>
          </variablelist>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term><emphasis role="bold">TEST</emphasis> — [<emphasis
        role="bold">!</emphasis>]<emphasis>value</emphasis>[/<emphasis>mask</emphasis>][<emphasis
        role="bold">:C</emphasis>]</term>

        <listitem>
          <para>Defines a test on the existing packet or connection mark. The
          rule will match only if the test returns true. Tests have the
          format</para>

          <para>If you don't want to define a test but need to specify
          anything in the following columns, place a "-" in this field.</para>

          <variablelist>
            <varlistentry>
              <term>!</term>

              <listitem>
                <para>Inverts the test (not equal)</para>
              </listitem>
            </varlistentry>

            <varlistentry>
              <term><emphasis>value</emphasis></term>

              <listitem>
                <para>Value of the packet or connection mark.</para>
              </listitem>
            </varlistentry>

            <varlistentry>
              <term><emphasis>mask</emphasis></term>

              <listitem>
                <para>A mask to be applied to the mark before testing.</para>
              </listitem>
            </varlistentry>

            <varlistentry>
              <term><emphasis role="bold">:C</emphasis></term>

              <listitem>
                <para>Designates a connection mark. If omitted, the packet
                mark's value is tested.</para>
              </listitem>
            </varlistentry>
          </variablelist>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term><emphasis role="bold">LENGTH</emphasis> (Optional) -
        [<emphasis>length</emphasis>|[<emphasis>min</emphasis>]<emphasis
        role="bold">:</emphasis>[<emphasis>max</emphasis>]]</term>

        <listitem>
          <para>Packet Length. This field, if present allow you to match the
          length of a packet against a specific value or range of values. You
          must have iptables length support for this to work. A range is
          specified in the form
          <emphasis>min</emphasis>:<emphasis>max</emphasis> where either
          <emphasis>min</emphasis> or <emphasis>max</emphasis> (but not both)
          may be omitted. If <emphasis>min</emphasis> is omitted, then 0 is
          assumed; if <emphasis>max</emphasis> is omitted, than any packet
          that is <emphasis>min</emphasis> or longer will match.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term><emphasis role="bold">TOS</emphasis> —
        <emphasis>tos</emphasis></term>

        <listitem>
          <para>Type of service. Either a standard name, or a numeric value to
          match.</para>

          <programlisting>         <emphasis role="bold">Minimize-Delay</emphasis> (16)
         <emphasis role="bold">Maximize-Throughput</emphasis> (8)
         <emphasis role="bold">Maximize-Reliability</emphasis> (4)
         <emphasis role="bold">Minimize-Cost</emphasis> (2)
         <emphasis role="bold">Normal-Service</emphasis> (0)</programlisting>
        </listitem>
      </varlistentry>
    </variablelist>
  </refsect1>

  <refsect1>
    <title>Example</title>

    <variablelist>
      <varlistentry>
        <term>Example 1:</term>

        <listitem>
          <para>Mark all ICMP echo traffic with packet mark 1. Mark all peer
          to peer traffic with packet mark 4.</para>

          <para>This is a little more complex than otherwise expected. Since
          the ipp2p module is unable to determine all packets in a connection
          are P2P packets, we mark the entire connection as P2P if any of the
          packets are determined to match.</para>

          <para>We assume packet/connection mark 0 means unclassified.</para>

          <programlisting>       #MARK/    SOURCE    DEST         PROTO   PORT(S)       SOURCE  USER    TEST
       #CLASSIFY                                              PORT(S)
       1         0.0.0.0/0 0.0.0.0/0    icmp    echo-request
       1         0.0.0.0/0 0.0.0.0/0    icmp    echo-reply
       RESTORE   0.0.0.0/0 0.0.0.0/0    all     -             -       -       0
       CONTINUE  0.0.0.0/0 0.0.0.0/0    all     -             -       -       !0
       4         0.0.0.0/0 0.0.0.0/0    ipp2p:all
       SAVE      0.0.0.0/0 0.0.0.0/0    all     -             -       -       !0</programlisting>

          <para>If a packet hasn't been classifed (packet mark is 0), copy the
          connection mark to the packet mark. If the packet mark is set, we're
          done. If the packet is P2P, set the packet mark to 4. If the packet
          mark has been set, save it to the connection mark.</para>
        </listitem>
      </varlistentry>
    </variablelist>
  </refsect1>

  <refsect1>
    <title>FILES</title>

    <para>/etc/shorewall/tcrules</para>
  </refsect1>

  <refsect1>
    <title>See ALSO</title>

    <para><ulink
    url="http://shorewall.net/traffic_shaping.htm">http://shorewall.net/traffic_shaping.htm</ulink></para>

    <para><ulink
    url="http://shorewall.net/MultiISP.html">http://shorewall.net/MultiISP.html</ulink></para>

    <para><ulink
    url="http://shorewall.net/PacketMarking.html">http://shorewall.net/PacketMarking.html</ulink></para>

    <para>shorewall(8), shorewall-accounting(5), shorewall-actions(5),
    shorewall-blacklist(5), shorewall-ecn(5), shorewall-exclusion(5),
    shorewall-hosts(5), shorewall-interfaces(5), shorewall-ipsec(5),
    shorewall-maclist(5), shorewall-masq(5), shorewall-nat(5),
    shorewall-netmap(5), shorewall-params(5), shorewall-policy(5),
    shorewall-providers(5), shorewall-proxyarp(5), shorewall-route_rules(5),
    shorewall-routestopped(5), shorewall-rules(5), shorewall.conf(5),
    shorewall-tcclasses(5), shorewall-tcdevices(5), shorewall-tos(5),
    shorewall-tunnels(5), shorewall-zones(5)</para>
  </refsect1>
</refentry>