Posts Tagged ‘spam’

Integrating SpamAssassin with qmail: Part 2

Wednesday, December 24th, 2008

This is a series of articles covering integration of SpamAssassin with qmail on a Linux box.

Part 1: Installing and Configuring SpamAssassin
Part 2: Marking email as spam

Part 2: Marking email as spam

Now, that we setup SpamAssassin to run as a continous process, we are able to change the qmail system to feed all emails into the server daemon. We need the root folder of qmail first. This is usually at /var/qmail. However, you better check with your installation first.

Create a file “qmail-queue.spamd” in subfolder bin that contains a single line:

/usr/bin/spamc -U /tmp/spamd_full.sock| /var/qmail/bin/qmail-queue.orig

Adapt the paths if necessary. Next step is to rename the existing qmail-queue program in subfolder bin. Name it “qmail-queue.orig”, as we have already used that pathname in our script. Make sure that all file permissions of qmail-queue.orig and qmail-queue.spamd match exactly the original qmail-queue binary.

Last step is to replace the existing qmail-queue binary by a link to our qmail-queue.spamd script. That’s it. All your emails do now pass the SpamAssassin daemon. You can check this by viewing all headers of emails passing your system. They should now contain additional SpamAssassin lines.

This is not the end of the story. We just marked email so far as spam or not. The will not get filtered out of the boxes, yet. This however is the topic of part 3 of this series.

Integrating SpamAssassin with qmail: Part 1

Sunday, November 23rd, 2008

This is a series of articles covering integration of SpamAssassin with qmail on a Linux box.

Part 1: Installing and Configuring SpamAssassin
Part 2: Marking email as spam

Part 1: Installing and Configuring SpamAssassin

There are quite a few numbers of HOWTOs at the internet about installing the software itself. So I won’t go very much into details but rather point you to some locations where you can find sufficient information.

You’ll find the latest software package at Apache’s SpamAssassin Homepage. Unpack the archive, preferrably at /usr/local/src. It will produce a directory Mail-SpamAssassin-XXXX. Change into that directory and read the INSTALL file to learn about special features when building the spam recognition tool. Usually you need to issue three commands:

perl Makefile.PL
make
make install

That’s it. Be aware that you might need to enhance your Perl distribution by additional modules from CPAN.

The last step to perform is to make a tool called spamd running continously on your box. We will first configure the daemon according to your Linux distribution. On latest SuSE editions this is done by a file /etc/sysconfig/spamd:

## Path:           Network/Mail/Spamassassin
## Description:    Arguments for the spam daemon
## Type:           string
## Default:        "-d -c -L"
## ServiceRestart: spamd
#
# The arguments passed to spamd.
# See spamd(1) man page.
# Default is "-d -c -L"
SPAMD_ARGS="-d -c -u spamd -g spamd --socketpath=/tmp/spamd_full.sock"

We introduced a user and group called “spamd” here. You might need to configure them first on your system.

Finally, you can add according startup commands in your /etc/rc.d directory to make spamd starting at system boot. Here is a script that I use.

Part 2 of this series will concentrate on the issue how to pass each mail into SpamAssassin.

Prevent Spamming

Thursday, November 22nd, 2007

I usually get annoyed by spam robots. They are able nowadays to even bypass captchas. So what helps? I recently read an article saying that scientists work on a new kind of spam filters that can identify spam by the way the actual text looks like. That raised an idea in my head. Why not just count the number of links that a new guestbook entry contains? Usually this is what they do at my guestbook. They leave dozens of links. So I added a simple count in my guestbook plugin. Whenever there are too many links, I just ignore the entry. 🙂