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Old 03-05-2013, 09:46 PM   #1
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Registered: Jan 2013
Location: Central NY
Distribution: Mac, debian
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Port knocking utility: How to monitor sshd?

I am looking around for a simple port knocking utility that will open, allow exception on port 22 for whatever IP, and immediately close when the connection is closed.

I was messing with cd00r.c, which appears to work, but I would need to edit the file for my purposes, but to do that I need to learn how to use pcap, and I was wondering if there was an easier way, like when cd00r gets the right combo, it would run (apparently you put this in yourself, cd00r.c does nothing by default)
execv(sprintf("iptables -A INPUT -i %s -s %s -j ACCEPT",CDR_INTERFACE,in_addr));
and then run an opposite command when cd00r detects a FIN packet. I wonder if there is some simple script or file I can edit that sshd would execute or execute when the sshd closes a connection?
Old 03-07-2013, 10:49 AM   #2
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Registered: Jan 2004
Location: georga
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I dont know if this will help but I have found these 2 sites:

Looks like an interesting idea and I may have to try...
1 members found this post helpful.


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