Sender Policy Framework

Reference Implementation: Mail::SPF::Query

The Perl module Mail::SPF::Query has been the very first implementation of SPF and is currently the de facto reference implementation. It roughly conforms to the final SPFv1 specification, however due to its long heritage (reaching back to 2003) there are some deviations. The Mail::SPF::Query package includes a comprehensive test suite, a command-line query tool, a query server, and sample plugins for several mail servers. The library also supports a number of non-standard features, such as best-guess processing and trusted forwarder accreditation checking. Currently, pyspf is the most RFC 4408 conformant implementations released as a separate package (the jSPF library is also reported to pass all tests in the test suite).

The project is currently working on a new Perl module, Mail::SPF, to replace Mail::SPF::Query as the reference implementation (ETA December 2006).

Libraries

Extensions and Patches for Mail Servers

Extensions for Mail Clients

Note that performing SPF checks in the mail client is problematic because it is often difficult to accurately obtain the required information from delivered messages.

Other Software that supports SPF

Please report SPF-supporting software to the spf-discuss mailing list or by contacting us directly.