LinuxMagic - OpenSource - Dynamic Regex

Dynamic Regular Expression Anti-Spam Tools

At LinuxMagic, we have been using Dynamic Regular Expression Testing as part of our suite of tools, used to identify address spaces that are not meant to be mail servers. Mail Servers should ALWAYS follow 'Best Practices' when operating, and administrators should know that an IP Address that is used for operating a mail server, should have a Reverse DNS Entry that indicates whom is responsible for the mail servers. Ie, '' or '' etc.

If the reverse DNS resolves to a general format such as '' it is much more likely to be a infected PC or Spam Bot, that is sending the mail, and give no indication that a responsible operator is maintaining the service. Since not all network operators submit to DUL lists, this is a highly effective tool to identify such bots. And as per our 'philosophy', we only accept mail from mail servers which use best practices, so this technology helps to ensure that we can stop such bots, 'pre-filtering'.

We have now decided to make this technology available to the general public, and you can now generate regular expression lists from our database, to use in your own mail servers and anti-spam tools, as well as helping the overall cause by helping to maintain the database, and identify new regular expressions as they are discovered.

You can generate your lists easily from our database:

You can select by:

  • DUL Style Entries Only (eg.
  • Non-DUL Style Entries Only (eg.
  • Both Styles
  • Stable Only
  • Stable and Testing Entries Only
  • Stable, Testing and User Contributed
  • Stable, Testing and User Contributed (User Contrib with Multiple Votes)
  • Exclude Challenged Entries

NOTE: The license allows anyone to use this technology, providing it is for non-commercial use, or for mail servers with less than 500 email addresses. If you are making money with this technology, we would appreciate your support for this project by 'Licensing' your implementation. For single server instances, licensing starts as low as $100/yr. Commercial Anti-Spam Vendors should contact us for other Licensing Models.

LinuxMagic is a proud supporter of the OpenSource movement, and these pages include some of our contributions back to the community. Various tools, scripts, and programs that have been developed in house are listed on these pages, as well as offering a home to other opensource projects that have been contributed by other individuals and companies that also support the movement. If you have a request for services or feel that something else of importance to the community should belong here, by all means contact us at, and we can see what we can do. Remember, LinuxMagic is also is available to develop custom Linux Applications on contract, and also offers support and services contracts.