LinuxSecurity.com
Share your story
The central voice for Linux and Open Source security news
Home News Topics Advisories HOWTOs Features Newsletters About Register

Welcome!
Sign up!
EnGarde Community
Login
Polls
What is the most important Linux security technology?
 
Advisories
Community
Linux Events
Linux User Groups
Link to Us
Security Center
Book Reviews
Security Dictionary
Security Tips
SELinux
White Papers
Featured Blogs
All About Linux
DanWalsh LiveJournal
Securitydistro
Latest Newsletters
Linux Advisory Watch: July 18th, 2014
Linux Advisory Watch: July 13th, 2014
Subscribe
LinuxSecurity Newsletters
E-mail:
Choose Lists:
About our Newsletters
RSS Feeds
Get the LinuxSecurity news you want faster with RSS
Powered By

  
( IPCHAINS rulesets on 2.4.x kernels ) - What the ipchains.o module can do on 2.4.x kernels

7.40. ( IPCHAINS rulesets on 2.4.x kernels ) - What the ipchains.o module can do on 2.4.x kernels

Some people would like to continue using their legacy IPCHAINS rulesets on 2.4.x-based kernelw. Unfortunately, unless you are only doing packet firewalling and not trying to do any NATing (MASQ), PORTFW, or other advanced features, you're in trouble.

  • If you ARE only doing IPCHAINS filtering, all you need to do is unload all IPTABLES modules shown from the "/sbin/lsmod" command. After that, load the IPCHAINS module by running "/sbin/modprobe ipchains". After that, load your IPCHAINS ruleset as normal.

    • Please note that if you compiled IPTABLES support statically into the kernel, you CANNOT load the "ipchains" module (it shouldn't be even present) as it will conflict with the IPTABLES kernel code. Your ONLY option in this case is to recompile your kernel but make the IPTABLES and IPCHAINS options as modules.

So why can't you run IPCHAINS MASQ/PORTFW functionality with a 2.4.x kernel? Once the IPCHAINS module is loaded, you CANNOT use any IPTABLES commands or modules since the code conflicts. In addition to this, you cannot use any legacy 2.2.x IPCHAINS masq modules on a 2.4.x kernel as the kernels are so radically different. Plus, this really shouldn't be an issue as all of this functionality is available via native IPTABLES modules now. Finally, you cannot use the IPMASQADM tool with a 2.4.x kernel as the program both won't compile and ultimately the PORTFW kernel handlers aren't present anymore (it's now done natively by the IPTABLES code). So, considering all of these facts:

  • You cannot run any form of PORTFW on this 2.4.x machine

  • Protocols that require special handling like FTP, IRC, CuSeeme, RealAudio, etc. will no longer work

Basically, the ipchains kernel module included with the 2.4.x kernels is intended for basic packet firewall compatibility and NOT any NAT(MASQ) functionality.

    
Partner

 

Latest Features
Peter Smith Releases Linux Network Security Online
Securing a Linux Web Server
Password guessing with Medusa 2.0
Password guessing as an attack vector
Squid and Digest Authentication
Squid and Basic Authentication
Demystifying the Chinese Hacking Industry: Earning 6 Million a Night
Free Online security course (LearnSIA) - A Call for Help
What You Need to Know About Linux Rootkits
Review: A Practical Guide to Fedora and Red Hat Enterprise Linux - Fifth Edition
Yesterday's Edition
Router hacking competition announced for Defcon
EFF wants hackers to help build an open, secure router
Hackers Could Take Control of Your Car. This Device Can Stop Them
Partner Sponsor

Community | HOWTOs | Blogs | Features | Book Reviews | Networking
 Security Projects |  Latest News |  Newsletters |  SELinux |  Privacy |  Home
 Hardening |   About Us |   Advertise |   Legal Notice |   RSS |   Guardian Digital
(c)Copyright 2014 Guardian Digital, Inc. All rights reserved.