qpsmtpd

qpsmptd is an SMTP daemon written in pure perl which is moduler in design, and allows the development of plugins to provide truely flexible handling of incoming email.

I've written many qpsmtpd plugins, some of which are standalone, and some which work together in a unified fashion to provide a flexible anti-SPAM solution. (The latter collection of plugins are distributed at the mail-scanning-lite page and are documented further in the mail-scanning.com writeup.)

This page contains those standalone plugins which I've put together, and which might be useful to others.

qpsmtpd plugins

badsubject

This plugin is will reject messages at SMTP-time if they have locally blacklisted Subject: headers.

check_bogus_bounce

Reject invalid bounce messages, which are bounces addressed to multiple recipients.

check_system_load

This plugin is designed to protect your mailserver from suffering in a DoS condition, by temporarily refusing new connections when your server load has risen above a configurable threshold.

log_details

This informational plugin will add headers to each incoming message to record the connecting hosts' IP address, DNS name, and similar details.

spam_gourmet

This flexible plugin allows you to generate and distribute transient email addresses, which expire after they have been used a given number of times.