NAME

qmail-dmarc - verify using DMARC and queue a mail message for delivery

DESCRIPTION

qmail-dmarc is designed to be called by qmail-smtpd instead of qmail-queue and will verify if incoming e-mail conforms to the DMARC policy of its sender domain:

  1. If the environment variable RELAYCLIENT exists, no verification is done, and the e-mail is immediately passed to qmail-queue.

  2. In any other case, we check if the message contains a valid DKIM signature matching the domain of the From: header field. If this is the case, the e-mail is passed to qmail-queue.

  3. If not, but the message has a From: domain contained in /var/qmail/control/rcpthosts and the environment variable DMARC_REJECT is set to a true value, the message is rejected with message 554 Valid DKIM signature required for sender domain ...

  4. If not, a SPF check is done, and a Received-SPF: header field is added to the message. Then we check if the message is aligned with its sender's DMARC policy. A DMARC-Status: header field is added.

    If the message does not align to the policy, the policy advises to reject such messages and when the environment variable DMARC_REJECT is set to a true value, the message will be rejected with 554 Failed DMARC test.

  5. In any other case the message is passed on to qmail-queue.

Diagnostic messages are written as a single line to standard error, so you should find them in your qmail-smtpd's log.

OPTIONS

Apart from controlling the rejection of messages via the environment variable DMARC_REJECT, none. It just works the way I need it. If you need it to operate in any other way, please let me know.

BUGS

Please report any bugs or feature requests to bug-app-qmail-dmarc at rt.cpan.org, or through the web interface at https://rt.cpan.org/NoAuth/ReportBug.html?Queue=App-Qmail-DMARC. I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.

SUPPORT

You can find documentation for this module with the perldoc command.

    perldoc App::Qmail::DMARC

You can also look for information at:

ACKNOWLEDGEMENTS

LICENSE AND COPYRIGHT

Copyright 2019 Martin H. Sluka.

This program is free software; you can redistribute it and/or modify it under the terms of the the Artistic License (2.0). You may obtain a copy of the full license at:

http://www.perlfoundation.org/artistic_license_2_0

Any use, modification, and distribution of the Standard or Modified Versions is governed by this Artistic License. By using, modifying or distributing the Package, you accept this license. Do not use, modify, or distribute the Package, if you do not accept this license.

If your Modified Version has been derived from a Modified Version made by someone other than you, you are nevertheless required to ensure that your Modified Version complies with the requirements of this license.

This license does not grant you the right to use any trademark, service mark, tradename, or logo of the Copyright Holder.

This license includes the non-exclusive, worldwide, free-of-charge patent license to make, have made, use, offer to sell, sell, import and otherwise transfer the Package with respect to any patent claims licensable by the Copyright Holder that are necessarily infringed by the Package. If you institute patent litigation (including a cross-claim or counterclaim) against any party alleging that the Package constitutes direct or contributory patent infringement, then this Artistic License to you shall terminate on the date that such litigation is filed.

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