Ipfreeze is a program that listens to the netlink device. It takes the source address from every incoming packet and adds it to a Netfilter "blacklist" chain. The address is removed from this chain after a user-definable period of time. This allows you to create rules that detect and halt certain odd behaviors, such as ports scans, syn floods, or connection attempts on forbidden ports. The attacker's IP address is blacklisted using the QUEUE target. There is also a whitelist where you can declare hosts that you never want to be blacklisted.
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