tpop3d is a fast, extensible, secure UNIX POP3 server. `Extensible' is used specifically in the context of new authentication mechanisms. Presently the distribution contains auth-pam, which uses Linux-style Pluggable Authentication Modules to mediate access of registered users of a machine to their Unix-style mailboxes, auth-passwd for older Unix machines, and auth-mysql, which works with vmail-sql or other MySQL-based solutions to mediate access to virtual-domain email. auth-pgsql supplies similar functionality for PostgreSQL. auth-ldap allows authentication of users against an LDAP directory, and auth-flatfile uses files in the format of /etc/passwd. In addition, there are two authenticators which are designed to allow easy implementation of new authentication schemes without writing C code: auth-other, which allows you to write an external program to communicate with tpop3d via pipes; and auth-perl, which allows you to embed a perl interpreter in tpop3d to authenticate users with custom perl code. tpop3d supports TLS/SSL for encrypted communications.
tpop3d makes POP-before-SMTP relaying easy, providing configurable hooks which allow you to insert rows into a database, or call custom code either running in an embedded perl interpeter or in an arbitrary external program whenever a user is authenticated. The same facilities can be used to implement POP3 server `bulletin' support. In addition, tpop3d can notify a DRAC (`dynamic relay authentication control') or WHOSON server of logins.
tpop3d supports traditional (BSD-format) mailspools and, thanks to the efforts of Paul Makepeace, the maildir format of qmail. Location and type of mailspools can be selected flexibly at run time using the configuration file. There is also experimental support for index caching to improve performance with BSD mailspools; this is in the latest version. Adding support for new mailbox formats would be simple.
tpop3d is portable to modern systems. It builds successfully `out of the box' on Linux, modern BSD systems, Solaris and Mac OS X. The GNU autoconf mechanism is used to configure and build tpop3d (thanks to Mark Longair for this contribution), so should also build on other reasonable Unix systems.
tpop3d is free software, available under the terms of the GNU GPL.
tpop3d was created by Chris Lightfoot (Rest In Peace, Chris).
These details are provided for information only. No information here is legal advice and should not be used as such.