====== KopKop ======

{{:blog:code:kopkop_0.1.0-1.tar.gz|}} - Stealthy and secure remote command triggering for IP networks. The kopkop daemon listens for encrypted, signed and fully random-looking command packets. Only the fields essential for the packets' travel trough the internet are filled with 'sane' data. Upon reception and after a preset timeout it executes user defined commands. This could be used to open firewalls, allow hosts, etc., so one can reduce your system's attack surface by hiding services like 22/tcp ssh or 1000/tcp webmin. The packet sending mechanism a.k.a. the kopkop client is also included. The communication is strictly unidirectional and quite minimal between the client and the server altough random padding is used to spread the packet size between 120bytes and 8Kbytes. Replay attacks are forestalled by storing and comparing monotoneously increasing packet ids on both sides. 

{{tag>util security network monitor c}}

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