It has been way too long without posting a longer item, so... I recicled a script I wrote for a customer, and here it is:
A python script that lists (almost) all email addresses in a qmail system.
Also, a slightly tweaked CSS, thanks to Georg!
Adds tarpitting to qmail-smtpd, which is almost mandatory for a modern large SMTP server.
Too bad it's not progressive tarpitting, but that's easy to fix :-)
Now all I need is a patch to make qmail-smtpd check local rcpt's validity and I'm completely trouble-free with it.
I just spent the afternoon at a client's hacking qmail+courier to work storing mail on a NT server.
Why? Well, migration issues, from NT to Linux.
And what had to be hacked? Lots.
You can't chmod over SMB
You can't link() over SMB (you can unlink(), though), so in order to have atomic message moves from Maildir/tmp to Maildir/new and whatever, rename()
Good thing this was a single-UID qmail system: you can't chown either ;-)
Courier's metadata is created on Maildir/tmp and moved: same problem as above
Cranky permission checks fixed via uid,gid,fmask mount options.
It had to work with a canned webmail thing, which expects all mail to be in one folder on disk, so Maildir/cur and Maildir/new have to be symlinks to a single folder.
Since you can't have symlinks on SMB, Maildir is local, but subdirs of it are symlinks to the SMB-mounted thing
Then courier's pop doesn't work because you can't rename from Maildir/tmp (over SMB) to maildir/courierpopwhatever (local), so hack courier to use mkstemp or whatever
Then courier got each mail twice. Looks like it sees two UIDLs for the same file, depending on whether it's read or not (my guess: because we are mixing Maildir/cur and Maildir/new on one folder). Make courier use alternative UIDL format and it works.
And so on. About two hours, and I am pretty sure noone has ever done something like this before. On the other hand, when noone has done something like this before, they usually had a very good reason!
I have been using Bruce Guenter's nice Qmail rpms for years, but he doesn't seem to be working on them much.
So, I just fixed a couple of issues:
TLS Support
errno fix (for glibc 2.3)
svc-add smtpd (silly)
So, it now builds out-of-the-box on RH8 and RH9.
I should open a sf.net site for them, probably. Add CRAM-MD5 authentication (I have it working with a plain file, LDAP would be nicer), a working courier RPM (tricky to build sometimes), a little extra stuff (antivirus, spamassassin, autoresponder) and it's really a nice mail server in a box.
Part II of the series. In this article, we replace qmail-smtpd with qpsmtpd, which is more flexible and spam-aware.