Free Add-on Software
I am pleased to contribute software back to the open-source and qmail / netqmail communities, subject to 'GPL' license or similar restrictions - please see the specific package for details. Currently 4 packages and 1 patch are offered (all qmail-related); all are found on my Free Stuff Microsite:
- qmail-errmsg: This adds extensive logging for incoming SMTP to qmail[-smtpd].
- greydaemon: This add-on for netqmail by John Levine (I wrote the 'glue' and documentation) provides full greylisting to reduce spam.
- qmail-verify: This adds a an extra component to qmail to verify the existence of users' mailboxes. This is used during the SMTP session to determine if a message should be accepted. It is a comprehensive update to Paul Jarc's realrcptto patch.
- spamrefuse: This patch extends netqmail to refuse spammy messages at SMTP time. It assumes incoming messages are scanned by SpamAssassin: The resulting score is checked against a supplied threshold and the message refused if the threshold is exceeded.
- qmail-hashdir: This extends qmail's functionality by adding a system to manage users' directories (and the Maildirs there) in a scalable manner. It allows for an almost unlimited number of mailboxes on a system, across multiple domains, optionally also on multiple machines with shared mailbox storage. It uses a command-line interface, so is easily integrated with existing user-management systems.
- radcheckpassword: A drop-in replacement for the checkpassword program typically used to authenticate from the system's /etc/passwd database. Instead of consulting this database, external Radius server(s) are consulted.
- couriercheckpassword: Another drop-in replacement for checkpassword, this time providing a way of using Courier's authentication methods which include LDAP.
- Early talker patch: This patch enables you to add a pause before qmail-smtpd issues its SMTP greeting, terminating the session if the remote system sends SMTP commands early, behaviour typically associated with 'Zombie' machines sending spam.