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  <articleinfo>
    <title>Shorewall and ipp2p</title>

    <authorgroup>
      <author>
        <firstname>Tom</firstname>

        <surname>Eastep</surname>
      </author>
    </authorgroup>

    <pubdate>2004-11-04</pubdate>

    <copyright>
      <year>2004</year>

      <holder>Thomas M. Eastep</holder>
    </copyright>

    <legalnotice>
      <para>Permission is granted to copy, distribute and/or modify this
      document under the terms of the GNU Free Documentation License, Version
      1.2 or any later version published by the Free Software Foundation; with
      no Invariant Sections, with no Front-Cover, and with no Back-Cover
      Texts. A copy of the license is included in the section entitled
      <quote><ulink url="GnuCopyright.htm">GNU Free Documentation
      License</ulink></quote>.</para>
    </legalnotice>
  </articleinfo>

  <section>
    <title>Introduction</title>

    <para>Shorewall verions 2.2.0 and later include support for the ipp2p
    match facility. This is a departure from my usual policy in that the ipp2p
    match facility is included in Patch-O-Matic-NG and is unlikely to ever be
    included in the kernel.org source tree. Questions about how to install the
    patch or how to build your kernel and/or iptables should not be posted on
    the Shorewall mailing lists but should rather be referred to the Netfilter
    Mailing List.</para>
  </section>

  <section>
    <title>Scope</title>

    <para>In the following files, the "PROTO" or "PROTOCOL" column may contain
    "ipp2p":</para>

    <simplelist>
      <member><ulink
      url="Documentation.htm#Rules">/etc/shorewall/rules</ulink></member>

      <member><ulink
      url="traffic_shaping.htm">/etc/shorewall/tcrules</ulink></member>

      <member><ulink
      url="Accounting.html">/etc/shorewall/accounting</ulink></member>
    </simplelist>

    <para>When the PROTO or PROTOCOL column contains "ipp2p" then the DEST
    PORT(S) or PORT(S) column may contain a recognized ipp2p option; for a
    list of the options and their meaning, at a root prompt type:</para>

    <programlisting><command>iptables -m ipp2p --help</command></programlisting>

    <para>You must not include the leading "--" on the option; Shorewall will
    supply those characters for you. If you do not include an option then
    "ipp2p" is assumed (Shorewall will generate "-m ipp2p --ipp2p").</para>
  </section>

  <section>
    <title>Example (assumes that you are running Shorewall 2.2.0 Beta 3 or
    later):</title>

    <para>Example 2 in the ipp2p documentation recommends the following
    iptables rules:</para>

    <programlisting>01# iptables -t mangle -A PREROUTING -p tcp -j CONNMARK --restore-mark
02# iptables -t mangle -A PREROUTING -p tcp -m mark ! --mark 0 -j ACCEPT
03# iptables -t mangle -A PREROUTING -p tcp -m ipp2p --ipp2p -j MARK --set-mark 1
04# iptables -t mangle -A PREROUTING -p tcp -m mark --mark 1 -j CONNMARK --save-mark

05# iptables -t mangle -A POSTROUTING -o eth0 -m mark --mark 1 -j CLASSIFY --set-class 1:12
06# iptables -t mangle -A POSTROUTING -o eth1 -m mark --mark 1 -j CLASSIFY --set-class 2:12</programlisting>

    <para>These are implemented in the /etc/shorewall/tcrules file as
    follows:</para>

    <programlisting>#MARK                SOURCE        DEST        PROTO        PORT(S)        CLIENT     USER    TEST
#                                                                          PORT(S)
RESTORE:P            -             -           tcp
CONTINUE:P           -             -           tcp          -              -          -       !0
1:P                  -             -           ipp2p        ipp2p
SAVE:P               -             -           tcp          -              -          -       1
1:12                 -             eth0        -            -              -          -       1
2:12                 -             eth1        -            -              -          -       1    </programlisting>
  </section>
</article>