Automatically learn Spam/Ham on your own IMAP server

January 30th, 2013 Comments off

There are these little things on your server, you set them up once – then a long time passes – and then you realize, it is really helping you a lots and (most importantly) it is still working.

One of these things for me is how I handle Spam/Ham on my IMAP server. I had initially the idea to automate this as much as possible and let the computer/machine do the work (and I don’t have to worry about it anymore).

I have a number of IMAP folders, obviously “INBOX”, “LearnAsHam”, “LearnAsSpam” and “Spam”. If I have an email in my “INBOX” what is spam I’ll move it into “LearnAsSpam”. It will be picked up by a process I’ll explain later and moved into “Spam”. If there is a false positive in “Spam” I move it to “LearnAsHam” and after a process picks it up it ends up in “INBOX” again.

And this “process” is basically fetchmail feeding it through sa-learn with “–spam” or “–ham” as its parameter.

The relevant shell commands I think I got from here. A bit of a biest, but they’ll work.

Categories: Scripting Tags:

What is the answer to this captcha?

January 30th, 2013 Comments off

Screenshot from 2012-07-13 22:48:36

… best captcha I ever had. And yes, I do play chess… *g

Categories: Fun Tags:

How do I test my IPv6 capable mailserver? II

June 26th, 2012 Comments off

Now you have IPv6 enabled on your mail server but you don’t know any email address what is actually IPv6 enabled as well?

Here are two – what I just tested:

  • ipv6@test-ipv6.veznat.com
  • bouncer@freenet6.net
  • my own… hehe.

Both are sending back the mail headers and the first one also shows you DNS info for the return path.

Categories: IPv6 Tags:

kill -9 $$

June 26th, 2012 Comments off

I hate it when I keyed in a password on a shell prompt and pressed enter already.

This is short, easy to remember and doesn’t do nasty things like editing your history file…

PS: Works definitely with bash, dont know about others.

Categories: Scripting Tags:

Two factor authentication with YubiKey

June 24th, 2012 Comments off

Yubikey with penguinTwo factor authentication with OTP – as provided by YubiKey – makes you sleep well at night again.

I recently figured that these substantially increase your password security – with what you know and what you have. They are very easy integrated into PAM – and the good news is most services on Linux can be configured to use PAM as an authentication source.

SSH, Dovecot, Apache… no problems.

The good thing is, these tokens are not expensive at all – 25 USD and they are yours or for 10 USD more you can even get one with RFID integrated. What more do you want?

Unfortunately still, there are only a few websites what are supporting these tokens, there are certainly plugins for some web applications like WordPress or SqurirrelMail. These are what I know of, there a certainly more.

I wrote a short article about these nearly 2 years ago – you can find it here.

Categories: Security Tags: