Port knocking project

1 - What this it

This is a simple implementation of Port Knocking techniques.
This sniffs network packets with determined keys and executes commands like firewall to open and close ports. In the client mode injects packets with key to server.
This is a personal project of the your author and is available for everybody by your GPL Licence.

2 - What is Port Knocking

In one instance, port knocking refers to a method of communication between two computers (arbitrary named here client and server) in which information is encoded, and possibly encrypted, into a sequence of port numbers. This sequence is termed the knock. The server initially presents no open ports to a public network and is monitoring all connection attempts. The client initiates connection attempts to the server by sending SYN packets to the ports specified in the knock. This process of knocking is what gives port knocking its name. The server offers no response to the client during the knocking phase, as it "silently" processes the port sequence. When the server decodes a valid knock it triggers a server-side process.

The definition of a valid knock is arbitrary, and up to the implementer. The server-side process is also arbitrary, and up to the implementer. The trigger may result in dynamic modification of firewall rules or other administrative system events.

3 - Timeline

* 20060228 - 0.0.6 released
* 20060110 - 0.0.5 released
* 20051114 - 0.0.4 released
* 20051111 - 0.0.3 released
* 20051101 - 0.0.2 released
* 20051020 - Initial release

4 - Install

Please run the install script that came together with this file.

5 - Uninstall

Please run the uninstall script that came together with this file.

6 - Download

0.0.4 - 11/14/2005
0.0.3 - 11/11/2005
0.0.2 - 11/01/2005
0.0.1 - 10/20/2005

7 - TODO

* Easy installer
* RPM packages to linux distributions
* Daemon mode
* Support to crypt file keys
* Support to OPIE

8 - About author

Andre Luiz Rodrigues Ferreira is a Computing Science student and Support Analist from Orlandia - SP - Brazil.
Yours prefered subjects are Computer Networks, Information Security and Intrusion Detections Systems.

He also love to play drum in the vacant hours :)

PS: Sorry by your poor english. He's learning...

9 - Contact, help and support

You can obtain more information, help, contacts and have support this software choosing this choices:

1 - Subscribe the mail list:
2 - Access the project forum:
3 - Access the Source Forge project:
4 - Talk with the author:

10 - How to help

Please reports bugs, patches and send documentation. The author will be happy! :)

11 - Links and references

Port Knocking project:
Linux Journal:
Dr. Dobb's:

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