Perl module to generate and check tokens to protect against CSRF attacks

 WWW::CSRF generates tokens to help protect against a website attack known as
 Cross-Site Request Forgery (CSRF, also known as XSRF). WWW::CSRF differs
 from most other CSRF modules on CPAN in that it is not bound to a specific
 framework, and thus can be used from any CGI script, or as a building block
 to write framework-specific CSRF mitigation modules.