How to learn from Shurdix

Introduction

Most of the features and methods used in Shurdix are usable in any linux distribution. As a typical programmer, I am lazy to write documentation and prefer to write code. Therefore it is not obvious how to profit from Shurdix’ development when using a different distribution.

The code is internally commented, and most programs are written in ash or perl, so at least in theory it can be understood pretty fast what it does and how it works. Sometimes minor editing may be necessary in order for the scripts to work in other linux distributions. Some require additional packages, patches or kernel modules.

This page was written to give you some hint how to profit from Shurdix’ programs in other distributions.

Getting the files

There are several options to obtain the files:

Download Shurdix ISO and boot it. The only required parameter is ROOTPW so that you can log in

Download Shurdix root filesystem and mount it, for example like this:

wget http://www.shurdix.org/download/shurdix-0.3.cramfs
mkdir /mnt/tmp
mount -t cramfs -o loop,ro shurdix-0.3.cramfs /mnt/tmp

Download Shurdix devel package, create a new directory and unpack it into it. Inside devel/scripts/src there you can find the Shurdix-specific programs. Unlike most linux source packages, this one doesn’t create its own directory, but is unpacked directly into the specified (usually current) directory.

Interesting files

Shurdix-specific

Feature	File	Usage remarks
Traffic control based on WRR	/usr/local/sbin/tc.sh	without parameters means start, with “-f” means stop. Needs htb, wrr, esfq and imq
OpenVPN tunnel	/etc/init.d/rcS	look inside function “ifup”
Firewall	/etc/init.d/rcS	look inside function “firewall”
IP Accounting (getting data)	/usr/local/sbin/ipacct.pl	based on ipt_ACCOUNT and rrdtool
IP Accounting (setting up)	/etc/init.d/rcS	look inside function “firewall”. based on ipt_ACCOUNT
IP Accounting (displaying)	/usr/local/sbin/httpd	look inside function “rrdpng”. you need perl module RRDs
User management (setting up)	/etc/inid.d/rcS	look inside function “firewall”
User management (DHCP)	/usr/local/sbin/updatedhcp.pl	configuration file is for dnsmasq
User management (updating)	/usr/local/sbin/inetaccess.sh	data is expected in /mnt/ramdisk/users.dat, subnets on eth1
Transparent SMTP Proxy	/usr/local/sbin/aspe.smtp.pl	you need to redirect traffic with iptables (-j REDIRECT or -j TPROXY)
Checking Windows for patches	/usr/local/sbin/vulncheck.pl	specify listening interface as first program argument
Hardware autodetection	/etc/init.d/rcS	look inside function “hwdetect”

Provided by third parties

Feature	File	Usage remarks
User management (listing)	ipset -nL	part of ipset
IP Accounting (listing)	iptaccount -l	part of iptaccount
All source patches	devel/patches/*	only in the devel package

Commments

Certain scripts expect eth0 or ppp0 to be the internet connection and eth1 to be the LAN.