mvmf: mvmtr -- Mail Transport Agent Receiver

Capsule Summary

Detailed Info

mvmtr is the receiver portion of a Mail Transport Agent (MTA).

mvmtr was initially designed to be used in place of qmail's qmail-smtpd program, but with a different control interface.

mvmtr makes use of the MFL scripting language, and invokes MFL function "hooks" (if present) at various stages in SMTP acceptance.

mvmtr is not a product, it is a program written primarily in C++, and you may freely download it and use it. That said, however, it is still in a perhaps perpetual beta state.

FAQ (last updated January 3, 2025)

The man page (last updated January 8, 2025).

Design Thoughts (last updated January 3, 2025)

mvmtr MFL hooks (last updated September 14, 2007)

qmail-smtpd compatibility notes (last updated May 10, 2006)

On the list of things yet to do and some things that have been done. (Very much empty, updated January 5, 2025 to make it more so)

Overview

mvmtr is an experimental project to build an MTA receiver that interacts well with the mvmda mail delivery agent. It incorporates the mfl scripting language, and provides hooks to MFL functions at various stages in the SMTP receipt process.

Initially, mvmtr is simply able to be used in place of qmail-smtpd. While it's not intended to be a drop-in replacement for qmail-smtpd (as one of the goals is to have a different control interface), it may be configured and compiled with basic qmail-smtpd control compatibility. See qmail-smtpd compatibility notes for more on that. It does, however, make use of the qmail back-end system.

mvmtr also has the ability to consult with the mail client assessment server (mvmcas) to make real-time observations, take individual action about, and give automatic feedback regarding each mail client. Use of mvmcas allows greylisting, blocking (administrative or automatic), and applying other parameters to each incoming SMTP connection.

Buzzword compatibility: STARTTLS, SPF, DKIM, DMARC