Tom Eastep 2007 Thomas M. Eastep 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 GNU Free Documentation License.

Manual chains were introduced in Shorewall-perl 4.0.6; for Perl programmers, manual chains provide an alternative to Actions with extension scripts. Manual chains are chains which you create and populate yourself using the low-level functions in Shorewall::Chains. Manual chains work in conjunction with the compile extension script and Inline PERL scripts. The general idea is like this: In the compile extension script, you define functions that you can call later using Inline PERL. These functions create a manual chain using Shorewall::Chains::new_manual_chain() and populate it with rules using Shorewall::Chains::add_rule(). The functions also call Shorewall::Config::shorewall() to create and pass a rule to Shorewall. The TARGET in that rule is the name of the chain just created. The functions defined in the compile script are called by Inline PERL statements. The arguments to those calls define the contents of the manual chains and the rule(s) passed back to Shorewall for normal processing.