Despoof is a utility that tries to determine if a received packet is in fact spoofed by checking the TTL. This command-line utility is intended for near real-time responding (such as being triggered from an IDS). The README explains it all. This utility is based on an idea by Donald McLachlan [don@mainframe.dgrc.crc.ca] (thanks Don!). Despoof runs on most Unix systems (tested on Linux, *BSDs), and requires libnet 1.0 and libpcap 0.4.
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