Integrating OSSEC with Cisco IOS

Published on Saturday, November 15, 2008

I rank OSSEC as one of my favorite pieces of open source software, and finally decided to play around with it more in my own free time. (Yup, I do this sort of stuff for fun). My goal was quite simple: send syslog packets from my Cisco to my "proxy" server, running OSSEC. I found that, although OSSEC supports Cisco IOS logging, it didn't really work. In fact, I couldn't find any examples or articles of anybody actually getting it to work.

I initially tried to get it to work "correctly," and soon settled to "just getting it to work." I implemented some rules in the local_rules.xml file, which worked, but I'm pretty stubborn, and wanted to do it "correctly." With a couple pots of tea, and the support of my girlfriend, I became much, much more familiar with OSSEC. The key (and a lot of credit) goes to Jeremy Melanson for hinting at some of the updates to the decoder.xml file that need to take place.

The first step is to read the OSSEC + Cisco IOS wiki page. Everything on that page is pretty straight forward. I then added three explicit drop rules at the end of my Cisco's ACL:


access-list 101 deny tcp any host log
access-list 101 deny ip any host log
access-list 101 deny udp any host log

( is my WAN IP, and I'm sure you could figure out pretty darn easily, but I'll x them out anyways).

To reiterate, OSSEC needs to be told to listen for syslog traffic, which you should be set on the Cisco. If you haven't done this, go re-read the wiki above.


On or around line 1550 in /var/ossec/etc/decoder.xml I needed to update the regex that was used to detect the syslog stream.


^%\w+-\d-\w+: |^: %\w+-\d-\w+:

^%\w+-\d-\w+: |^: %\w+-\d-\w+: 

^list \d+ (\w+) (\w+) 
(\S+)\((\d+)\) -> (\S+)\((\d+)\),
action, protocol, srcip, srcport, dstip, dstport


In the general OSSEC configuration file, re-order the list of rules. I had to do this because syslog_rules.xml includes a search for "denied", and that triggers an alarm.


Remember that these dropped events will go into /var/ossec/logs/firewall/firewall.log. Because this is my home connection, and I don't have any active_responses configured (yet!), I tightened the firewall_rules.xml file (lowering the frequency, raising the timeframe).

And in the end, I get a pretty email when somebody tries to port scan me.

Pretty email

OSSEC HIDS Notification.
2008 Nov 15 23:19:36

Received From: proxy->
Rule: 4151 fired (level 10) -> "Multiple Firewall drop events from same source."
Portion of the log(s):

: %SEC-6-IPACCESSLOGP: list 101 denied tcp ->, 1 packet 
: %SEC-6-IPACCESSLOGP: list 101 denied tcp ->, 1 packet 
: %SEC-6-IPACCESSLOGP: list 101 denied tcp ->, 1 packet 
: %SEC-6-IPACCESSLOGP: list 101 denied tcp ->, 1 packet 


Using Django with SQL Server and IIS

Published on Saturday, November 8, 2008

As you can tell from reading some of the other pages, I like Linux and open source. But I also like to answer the question "what if..." This post is my [brief] run down of answering "what if I could run Django on Server 2003 with SQL Server and IIS." Why, you may ask? To be honest with you, at this point, I don't really know. One of the deciding factors was seeing that the django-mssql project maintains support for inspectdb, which means I could take a stock 2003 server running SQL Server, inspect the DB, and build a web app on top of it. The Django docs offer a lengthy howto for using Django with IIS and SQL Server, but the website for PyISAPIe seems to have been down for the last month or so. Without further delay, below are my notes on installing Django with SQL Server and IIS.

1a) Install python-2.x.x.msi from

1b) Consider adding C:\Python25\ to your Path (right click My Computer, Advanced, Environment Variables. Enter in blahblahblah;C:\Python25\)

2) Download a 1.0+ branch of Django (and 7-zip if you need it)

3a) Extract the contents of the Django. From inside Django-1.0, execute:

C:\Python25\python.exe install

3b) Consider adding C:\Python25\Script to your path.

4) Look in C:\Python25\Lib\site-packages -- confirm there is a Django package.

5) Checkout django-mssql (, copy sqlserver_ado from inside source to the site-packages directory

6) Download and install PyWin32 from

7) Start a test project in C:\Inetpub\ called 'test'

c:\Python25\scripts\ startproject test

8a) Create a database using SQL Management Studio, create a user. (First, go to the Security dropdown. Right click Logins, add a new user. Next, right click Databases, New Database. Enter in the name, and change the owner to the user you just created).

8b) Edit the and add 'sqlserver_ado' and add database credentials. Use the below example if your database comes up in the Studio as COMPUTERNAME\SQLEXPRESS (you are using SQLExpress).

import os
DATABASE_ENGINE = 'sqlserver_ado'           # 'postgresql_psycopg2', 'postgresql', 'mysql', 'sqlite3' or 'oracle'.
DATABASE_NAME = 'crmtest'             # Or path to database file if using sqlite3.
DATABASE_USER = 'crmtest'             # Not used with sqlite3.
DATABASE_PASSWORD = 'password'         # Not used with sqlite3.
DATABASE_PORT = ''             # Set to empty string for default. Not used with sqlite3.

9) Install/download FLUP:

python install

10a) Download pyisapi-scgi from

10b) Extract the files to somewhere you can remember on your computer, like, c:\scgi

11) Double click

12a) Follow the directions here: -- I set a temporary different port since I'm just testing this out.

12b) The last few parts might be better served with an image or two:

Using an app pool to get the right permissions

(No resource/photo)

The SCGI configuration file

(No resource/photo)

Properties of the web site

(No resource/photo)
13) Start the scgi process from the Django folder directory

python runfcgi method=threaded protocol=scgi port=3033 host=

14) Test your django page,

(No resource/photo)

Upgrading Cisco Wireless Firmware

Published on Monday, November 3, 2008

I'm always forgetting the exact string to enter at the CLI for updating the IOS on a wireless Cisco AP, so I'll just put it here to end my future searches:

Chimp# archive download-sw /force-reload /overwrite tftp:// obviously being your tftp server, and the .tar file sitting in the root of the tftp server.

I suppose if you wanted to backup your IOS you could do something along the lines of:

Chimp# archive upload-sw tftp://

But I haven't tried it...

Configure Timevault to Remote Server

Published on Sunday, November 2, 2008

Using TimeVault with a shared drive as a backend is actually quite easy, but it does require a few special things setup. Note: this is gonna be a brief summary.

Install samba-tools, smbfs...

sudo apt-get install samba-tools smbfs

A lot more other stuff may install as well.

Create a script that mounts your samba share. You could also do this in fstab, but I tend to suspend my laptop when I come home, and I like clicking buttons.


mount -t cifs // /mnt/backups -o netbiosname=KELVIN-PC,iocharset=utf8,credentials=/home/kelvin/Apps/.smb-details.txt

smb-details.txt includes:


Finally, create a folder called 'timevault' or something inside your mapped share, then launch TimeVault and configure it to use the above mentioned /mnt/backups/timevault folder. Configure Timevault as normal.

Backup OpenFiler to S3

Published on

Backing up your Openfiler box to S3

While I don't think most pople would expect to backup their entire NAS/SAN to Amazon's S3, there might be a few very crucial things you need to backup. For instance, my girlfriend's PhD papers and data.

I've seen an implementation using Ruby and s3sync -- something that I do on my server -- but I'm trying to migrate everything to Python. Although there are a lot of great tools out there for S3, many of them Python-based, I wanted to do one thing and do it well: have one complete full backup available, and using as little bandwidth as possible. In these regards Duplicity would work well, except I wanted the ability to browse the S3 store using any other tool.

I've digged deeper into s3cmd, which I had noticed a long time ago, but I failed to notice it has a sync option. I have tested it out, and it appears to work very, very well. Here's how to use it with OF.

First, download s3cmd. You'll need to use subversion, so I first checked it out to my laptop, then uploaded it via SSH to OF. I put my s3cmd folder in /opt.

[root@files opt]# ls
openfiler s3cmd
[root@files opt]#

If you don't have elementtree installed, now is a good time to install it.

conary update elementtree:python

We need to next configure s3cmd with our AWS creds.

[root@files s3cmd]# ./s3cmd --configure

In the end I didn't configure encryption for my files (so just hit enter), but you may choose to do so. I have configured the transfer to use HTTPS, however.

Save settings? [y/N] y
Configuration saved to '/root/.s3cfg'

Cool. Now create a bucket on S3 for your NAS, e.g. blah2134accesskey.openfiler, using whatever method you choose (I typically use Cockpit). Now that you have a bucket, configure a *really* simple script to drop in cron:


/opt/s3cmd/s3cmd sync /mnt/openfiler/data/profiles/bunny s3://blah2134accesskey.openfiler/mnt/openfiler/data/profiles/bunny
/opt/s3cmd/s3cmd sync /mnt/openfiler/data/profiles/kelvin-pc s3://blah2134accesskey.openfiler/mnt/openfiler/data/profiles/knicholson/kelvin-pc

Sweet! I like this approach quite a bit: I get file-level access to anything on the NAS, you don't have to actually install anything, and it 'just works.'

PyGTK + py2exe for Windows

Published on

I'm writing down these quick notes so I can remember the steps for getting py2exe to work with GTK.

  • Download the GTK+ runtime
  • Download py2exe
  • Copy over your project into the windows box
  • Create a file (see below)
  • Run "c:\Python25\python.exe py2exe"
  • Copy over the lib, etc, and share folder from C:\Program Files\GTK2-Runtime into the dist folder
  • Run app!

from distutils.core import setup
import py2exe

name = 'ploteq',
description = 'Bunnys Plotting Tool',
version = '1.0',

windows = [
'script': '',

options = {
'py2exe': {
'includes': 'cairo, pango, pangocairo, atk, gobject', 


Slope Finder for the Missus

Published on

Since I do sysadminy stuff all day, I don't really get a chance to do much coding (or not as much of a chance as I would like). You can imagine my joy when my girlfriend expressed a problem she needed solved: "I'm going to need to solve 100s of slope equations, i.e. where two lines intersect. Can you write a program to do it?" Sure!

I asked if she wanted to do a batch input or just a one-off type of deal, she decided on the latter. Although I've done a fair bit of PyGTK stuff, I had never actually needed to convert it to Windows. I debated using IronPython -- but needed to use a special library to help solve the equations (I'm lazy).

So, where is the power in Python? After about 15-20m I had a console based app that could solve the slopes. I added the Linux GUI part in maybe 45m, and then the Windows part in, well, not 45m!

Either way, screenshot is below. Thanks girlfriend, I had fun!

Revised mod_tile Install HOWTO

Published on Saturday, November 1, 2008

This is the laundry list of things I did while creating a mod_tile VMware appliance based on Ubuntu Server 8.04. I've kept descriptions limited but left all the commands in. Let's start installing things...

Useful goodies for compiling source

sudo apt-get build-essential

More goodies for Mapnik + Friends

sudo apt-get install libboost-dev libboost-filesystem-dev libboost-filesystem1.34.1 libboost-iostreams-dev libboost-iostreams1.34.1 libboost-program-options-dev libboost-program-options1.34.1 libboost-python-dev libboost-python1.34.1 libboost-regex-dev libboost-regex1.34.1 libboost-serialization-dev libboost-serialization1.34.1 libboost-thread-dev libboost-thread1.34.1 libicu-dev libicu38 libstdc++5 libstdc++5-3.3-dev python2.5-dev

sudo aptitude install libfreetype6 libfreetype6-dev libjpeg62 libjpeg62-dev libltdl3 libltdl3-dev libpng12-0 libpng12-dev libtiff4 libtiff4-dev libtiffxx0c2 python-imaging python-imaging-dbg proj

sudo aptitude install libcairo2 libcairo2-dev python-cairo python-cairo-dev libcairomm-1.0-1 libcairomm-1.0-dev libglib2.0-0 libpixman-1-0 libpixman-1-dev libpthread-stubs0 libpthread-stubs0-dev ttf-dejavu ttf-dejavu-core ttf-dejavu-extra

sudo aptitude install libgdal-dev python2.5-gdal postgresql-8.3-postgis postgresql-8.3 postgresql-server-dev-8.3 postgresql-contrib-8.3

sudo aptitude install libxslt1.1 libxslt1-dev libxml2-dev libxml2 gdal-bin libgeos-dev libbz2-dev

sudo aptitude install apache2 apache2-threaded-dev apache2-mpm-prefork apache2-utils

sudo aptitude install subversion

This checks out the mapnik source:

svn co svn:// mapnik-src

Let's build mapnik with several specific locations included.

cd mapnik-src
python scons/ PYTHON=/usr/bin/python PGSQL_INCLUDES=/usr/include/postgresql PGSQL_LIBS=/usr/lib/postgresql BOOST_INCLUDES=/usr/include/boost BOOST_LIBS=/usr/lib

sudo python scons/ install PYTHON=/usr/bin/python PGSQL_INCLUDES=/usr/include/postgresql PGSQL_LIBS=/usr/lib/postgresql BOOST_INCLUDES=/usr/include/boost BOOST_LIBS=/usr/lib

And prepare a few things for the mapnik rendering...

svn co

cd ~/mapnik
tar -xpjf world_boundaries-spherical.tgz
cp coastlines/* world_boundaries/ 
rmdir coastlines 

Time to setup postgres. I have the intentions of running renderd (the mod_tile rendering engine) under whatever user Apache is running as, so I'll setup postgres to allow the OSM user to authenticate via password. I'm not a postgres expert, so if you see me doing something totally foolish, let me know.

sudo vi /etc/postgresql/8.3/main/pg_hba.conf

And edit the authentication part as so:

# Database administrative login by UNIX sockets
local   all         postgres                          ident sameuser
local   all         osm                               password sameuser

And now to actually configure postgres for the OSM data

sudo su postgres
createuser osm
createdb -E UTF8 -O osm gis
createlang plpgsql gis
psql -d gis -f /usr/share/postgresql-8.3-postgis/lwpostgis.sql
echo "ALTER TABLE geometry_columns OWNER TO osm; ALTER TABLE spatial_ref_sys OWNER TO osm;"  | psql -d gis
echo "alter user osm with password 'columbia';" | psql

sudo /etc/init.d/postgresql-8.3 restart

Now, let's render a sample image. Edit set-mapnik-env by changing the DB to 'gis', the username to 'osm', and the password to 'columbia'

cd mapnik
source ./set-mapnik-env
./customize-mapnik-map >osm.xml

If you get an error about it not finding a lib, make sure to do a...

sudo ldconfig

You should have an image called 'image.png' in the mapnik directory, and it should look distinctly like the UK.

svn co
cd osm2pgsql

Ok, that was easy. Let's load some data. I've used a sample snippit from Sydney in /home/osm to illustrate this.

./osm2pgsql -W -d gis ../sydney.osm

Type in the password used for postgres ('columbia')

I'll now check that the data is accessible by editing with the correct coords for Sydney.

ll = (150.29, -34.04, 151.25, -33.36)

Time to get mod_tile up and running.

sudo apt-get install libagg-dev

svn co
cd mod_tile

Depending on the revision of mod_tile you are using, you are going to have to edit the source before compiling. The two files you need to read through are the Makefile and render_config.h. I change the apxs and apachectl locations to the correct place (lines 2, 13 and 14). Since I did it on a x86 image, I took out any references to lib54 (line 33). In render_config.h, I made the following changes:

Line 8

#define WWW_ROOT "/var/www"

Line 23

#define OSM_XML "/home/osm/mapnik/osm.xml"

Removed references to lib64 on lines 26 and 29.

make && make install

Set it up as a module for apache by creating a file in /etc/apache/conf.d called 'mod_tile' and putting in there:

LoadModule tile_module /usr/lib/apache2/modules/

Created a folder called 'osm_tiles2' and 'direct' in /var/www, and make sure they are writable by whatever apache runs as (likely www-data). Restart apache.

From here, I created a file that automatically zooms in on the map I just created -- you can check it out here. Start the renderd process as www-data, and browse to the sample file.

cd ~/mod_tile
sudo su www-data

By now you should have a working mod_tile/OSM setup. After a change and tune a few things on the Ubuntu image I'll make the VMware image available for download. I can't wait to do some OSM projects!

Capped Internet

Published on

I've lived in several different parts of the world, and they all do internet differently. Back in the US I had 8Mb/sec cable (leaving just before Fios was really an option, darn!) In New Zealand, for instance, I was paying for "high speed ADSL" rated at 1.5Mb/256k. Vrooom. Up in Taiwan I was paying 1/2 what I paid in New Zealand, but for 12Mb/1Mb. Down to Sydney and we have a rated 24Mb/1Mb.

But there's a catch with the plans in New Zealand and Australia: they are 'capped'. This means you only get XGB/month -- and it isn't like Comcast capping at 250GB/month, I'm talking about 1GB/5GB/10GB and so forth. And there's more -- just like mobile phones, you get on-peak and off-peak times.

This all does make a bit of sense to me -- there are only X amount of tubes going in and out of NZ and AU, and I would imagine they get pretty clogged.

Either way, last month was pretty painful. Two weeks into our plan I checked out usage: 14GB of 18GB! We had only 4GB left to use for 15 days. This sounds like a lot, but for the two of us, and my 10 virtual servers, it isn't. The first thing I did was looking at a way to do WSUS with Linux -- I ended up using apt-cacher (I'm using only Ubuntu at home). BitTorrent, out; downloading any new ISOs, out; streaming music, totally out. For a while I has to VPN to home, and then VPN to a client, as our router at work didn't seem to like letting us access one of our clients. I even disconnected from the VPN if I wouldn't be doing work for 20m!

We eventually made it, and used only 2GB in two weeks. What an accomplishment!