pcap / libpcap

Discover PCAP,

• To capture packets,
• To virtualize network,
• To develop and run many network applications on the same PC but with different IP addresses,
• To monitor all the network traffic regardless the network settings of your PC.

Requirements

• libpcap-dev
  • install: sudo apt-get install libpcap-dev
  • check: ldconfig -p | grep pcap
    • libpcap version 1.8.1 (tested version, under /usr/lib/x86_64-linux-gnu/ )
• network tools
  • install: sudo apt install net-tools
  • check: ifconfig
    • You need to see information regarding your network.
• build-essential
  • install: sudo apt-get install build-essential
  • gcc --version
    • 7.0.4 required ( tested )
  • make --version
    • GNU make 4.1 required( tested )

Build & Run

• Build:
  • gcc pcapDiscovery.c -Wall -o pcapDiscovery -lpcap
• Run:
  • sudo ./pcapDiscovery

Working Principle

• When a packet is received, the actual lenght and the captured length will be written on the stdin.
• A fixed packet will be sent to network.

Test

• Type the command below to start capturing your default ethernet interface

  • sudo tcpdump

• If you can see a capture like the picture below when each packet is received, then it is working...

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