Policy daemon for Postfix, Sendmail and Zimbra, it allows MTA to check and modify mail envelope information, message MIME headers, and message body. It adds disclaimers, sent auto replies, strip attachments, block messages and rate limit outgoing emails.
Envelope Sender condition
An email message hat two addresses associated with sending it, the envelope sender, and the From address. The envelope sender is used by mail servers and From address is used by people. In most cases mail clients shows only From address, because the envelope sender and the From address should match. But they don’t always, and they don’t have to.
Match envelope sender with Wildcards or Regular Expressions, it gives a wide range of email address match possibilities.
*@gmail.com will match all messages which are sent from
To learn more visit MSH Traffic Policy website.