knockd-tools

Tools to use with Judd Vinet's knockd

ABOUT

This set of tools to use with Judd Vinet's knockd port-knocking server/client. The same functionality can be accomplished with a small script, but port-close which will stay in ram for hours and maybe days uses very little ram.

INSTALL

To install the tools in /usr/local/sbin run:

$ make
$ sudo make install

If you want other directories, edit Makefile and change:

INSTALL_DIR=/usr/local
SBIN_DIR=$(INSTALL_DIR)/sbin

Or simply copy port-open to whatever dir you want and make a sym or hard link port-close pointing to port-open

EXAMPLE

First you need to create iptables rules:

iptables -N knock
iptables -I INPUT -j knock 

For example configuration check knockd-example.conf

TEST

To test your installation you can run:

iptables -N knock
port-open 8.8.8.8 80 20
watch iptables -xvnL knock

You should see a rule accepting connections from 8.8.8.8 on port 80. After after 20 seconds the rule should disappear.

Chain knock (1 references)
    pkts      bytes target     prot opt in     out     source               destination
       0        0 ACCEPT     tcp  --  *      *       8.8.8.8              0.0.0.0/0           tcp dpt:80

LINKS

• Judd Vinet's knockd