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packet_crafting_raw_sockets

🛠️ Low-Level Packet Crafting with Raw Sockets and PacketGen​

Bypass higher‑level abstractions to craft custom Ethernet, IP, and ICMP packets using PacketGen. This is invaluable for network diagnostics, sending malformed packets, or simulating advanced protocols.

require 'packetgen'

# Build an ICMP echo request (ping)
pkt = PacketGen.gen('Eth', dst: 'ff:ff:ff:ff:ff:ff')
               .add('IP', src: '192.168.1.100', dst: '192.168.1.1')
               .add('ICMP')

# Set payload and recalculate checksums
data = 'RUBYNETWORK'
pkt.payload = data
pkt.calc

# Send raw packet
pkt.to_w

# Capture response with a filter
response = PacketGen.capture(iface: 'eth0', max: 1, timeout: 5, filter: 'icmp and src host 192.168.1.1')
puts "Received ICMP response: #{response.first.inspect}" if response.first