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Description

Tool for understanding and processing pcap (packet capture) expressions.

Caper is a tool for understanding and processing "pcap expressions" (also known as tcpdump filters) which are used for network packet analysis. Caper can be used for:

  • Expanding out pcap expressions "in full" to understand their implicit features.
  • Reasoning about whether two expressions accept the same set of packets, or how their accepted packets differ.
  • Converting pcap expressions into BPF programs.
  • Converting between pcap expressions and English.

More info can be found in the Caper paper (https://www.nik.network/caper/pcap_semantics.pdf).