Update docs for inline scripts

git-svn-id: https://shorewall.svn.sourceforge.net/svnroot/shorewall/trunk@7551 fbd18981-670d-0410-9b5c-8dc0c1a9a2bb
This commit is contained in:
teastep 2007-10-27 22:34:18 +00:00
parent d00d455930
commit fe10bfcd0f
2 changed files with 94 additions and 6 deletions

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@ -425,6 +425,83 @@ smtp,www,pop3,imap #Services running on the firewall</programlisting>
</example>
</section>
<section id="Inline">
<title>Inline Shell and Perl (Added in Shorewall-perl 4.0.6)</title>
<para>Earlier versions of Shorewall offered <ulink
url="shorewall_extension_scripts.htm">extension scripts</ulink> to allow
users to extend Shorewall's functionality. Extension scripts were designed
to work under the limitations of the Bourne Shell. With Shorewall-perl,
<firstterm>inline scripts</firstterm> offer a richer and more flexible
extension capability.</para>
<para>While inline scripts scripts may be written in either Shell or Perl,
those written in Perl have a lot more power.</para>
<para>Inline scripts can be either single-line or multi-line. Single line
scripts take one of the following forms:</para>
<itemizedlist>
<listitem>
<para><emphasis role="bold">PERL</emphasis> &lt;<emphasis>perl
script</emphasis>&gt;</para>
</listitem>
<listitem>
<para><emphasis role="bold">SHELL</emphasis> &lt;<emphasis>shell
script</emphasis>&gt;</para>
</listitem>
</itemizedlist>
<para>Shell scripts run in a child shell process and their output is piped
back to the compiler which processes that output as if it were embedded at
the point of the script.</para>
<para>Example: The following entries in
<filename>/etc/shorewall/rules</filename> are equivalent:<programlisting>SHELL for z in net loc dmz; do echo "ACCEPT $z fw tcp 22"; done</programlisting><programlisting>ACCEPT net fw tcp 22
ACCEPT loc fw tcp 22
ACCEPT dmz fw tcp 22</programlisting></para>
<para>Perl scripts run in the context of of the compiler process. To
produce output that will be processed by the compiler as if it were
embedded in the file at the point of the script, pass that output to the
shorewall() function. The Perl equivalent of the above SHELL script would
be:<programlisting>PERL for ( qw/net loc dmz/ ) { shorewall "ACCEPT $_ fw tcp 22"; }</programlisting>Perl
scripts are implicitly prefixed by the following:</para>
<programlisting>package Shorewall::User;
use Shorewall::Config qw/shorewall/;</programlisting>
<para>As part of the change that added inline scripts:</para>
<orderedlist>
<listitem>
<para>Compile-time extension scripts are also implicitly prefixed by
"package Shorewall::User;".</para>
</listitem>
<listitem>
<para>A <emphasis role="bold">compile</emphasis> extension script was
added for use by Shorewall-perl. That script is run early in the
compilation process and allows users to load additional modules and to
define data and functions for use in subsequent inline scripts and
extension scripts.</para>
</listitem>
</orderedlist>
<para>Multi-line scripts use one of the following forms:<programlisting><emphasis
role="bold">BEGIN SHELL</emphasis>
&lt;shell script&gt;
<emphasis role="bold">END</emphasis> [ <emphasis role="bold">SHELL</emphasis> ] [<emphasis
role="bold">;</emphasis>]</programlisting><programlisting><emphasis
role="bold">BEGIN PERL</emphasis> [;]
&lt;<emphasis>perl script</emphasis>&gt;
<emphasis role="bold">END</emphasis> [ <emphasis role="bold">PERL</emphasis> ] [<emphasis
role="bold">;</emphasis>]</programlisting></para>
<para></para>
</section>
<section id="dnsnames">
<title>Using DNS Names</title>

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@ -68,6 +68,12 @@
<para>The following scripts can be supplied:</para>
<itemizedlist>
<listitem>
<para>compile -- (Added in Shorewall-perl version 4.0.6). Invoked by
the Shorewall-perl compiler early in the compilation process. Must be
written in Perl.</para>
</listitem>
<listitem>
<para>init -- invoked early in <quote>shorewall start</quote> and
<quote>shorewall restart</quote></para>
@ -317,7 +323,7 @@ esac</programlisting><caution>
</row>
<row>
<entry>initdone</entry>
<entry>compile</entry>
<entry>clear</entry>
@ -325,7 +331,7 @@ esac</programlisting><caution>
</row>
<row>
<entry>maclog</entry>
<entry>initdone</entry>
<entry>isusable</entry>
@ -333,8 +339,7 @@ esac</programlisting><caution>
</row>
<row>
<entry>Per-chain (including those associated with
actions)</entry>
<entry>maclog</entry>
<entry>start</entry>
@ -342,7 +347,8 @@ esac</programlisting><caution>
</row>
<row>
<entry></entry>
<entry>Per-chain (including those associated with
actions)</entry>
<entry>started</entry>
@ -391,7 +397,12 @@ esac</programlisting><caution>
script returns a 'true' value; otherwise, the compiler will assume that
the script failed and will abort the compilation.</para>
<para>All scripts will need to begin with the following
<para>Beginning with Shorewall version 4.0.6, each compile-time script
is implicitly prefaced with:</para>
<programlisting>package Shorewall::User;</programlisting>
<para>Most scripts will need to begin with the following
line:<programlisting>use Shorewall::Chains;</programlisting>For more
complex scripts, you may need to 'use' other Shorewall Perl modules --
browse <filename