Introduction NFQUEUE is an iptables and ip6tables target which delegate the decision on packets to a userspace software. For example, the following rule will ask for a decision to a listening userpsace program for all packet going to the box: iptables -A INPUT -j NFQUEUE --queue-num 0 In userspace, a software must used libnetfilter_queue to connect to queue 0 (the default one) and get the messages
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