Packet parser by JavaScript

packet_parser.js

//=================================
//#     Author: MI SHAJIB
//=================================

// Sample packet in hex format
const packet = "450000280000400080060000c0a80101c0a80164";

// Convert packet to binary format
const packetBinary = Buffer.from(packet, "hex");

console.log("packetBinary -> ", packetBinary[0]);

// Parse header fields
const version = packetBinary[0] >> 4;
const headerLength = (packetBinary[0] & 0x0f) * 4;
const totalLength = packetBinary.readUInt16BE(2);
const protocol = packetBinary[9];
const sourceIP = packetBinary.slice(12, 16).join(".");
const destinationIP = packetBinary.slice(16, 20).join(".");

console.log("Version:", version);
console.log("Header length:", headerLength);
console.log("Total length:", totalLength);
console.log("Protocol:", protocol);
console.log("Source IP:", sourceIP);
console.log("Destination IP:", destinationIP);

// Parse data
const dataOffset = headerLength;
const data = packetBinary.slice(dataOffset, totalLength);

console.log("Data:", data.toString());