OpenSMTPD/OpenSMTPD-extras — pull request #2 by snimmagadda (2014-07-02 08:09:31+00:00)
Title: DKIM signer filter

This filter signs a message as specified in RFC 6376 using "simple" canonicalization algorithm. It accepts domain name(hostname as default), private key file name("/etc/ssl/private/rsa.private" as default) and selector("default" as default) as optional command-line parameters.

The signature generated by this filter is verified on gmail and yahoo mail (dkim=pass in headers).