Implementation and Setting Up a Single Firewall on a Network

📌 Description

The learning objective of this lab is two-fold:

1. Understanding how firewalls work
2. Setting up a simple firewall for a network

A stateless packet-filtering firewall is implemented, which inspects packets and decides whether to drop or forward them based on firewall rules. Through this implementation task, students will grasp the basic concepts of firewall functionality.

Linux has a built-in firewall based on Netfilter, known as iptables. Students will be given a simple network topology and asked to configure iptables rules to protect the network. This project will also explore interesting applications of iptables.

🔥 Topics Covered

• Firewall
• Netfilter
• Loadable Kernel Module
• Using iptables to set up firewall rules
• Various applications of iptables

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🛠 Languages and Utilities Used

• Python 🐍
• Ubuntu 20.04 VM 🐧

💻 Environments Used

• Windows 10 (21H2) 🖥️

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🚀 Program Walk-through

🛡 Task 1: Implementing a Simple Firewall

🔹 Task 1.A: Implement a Simple Kernel Module

🔹 Task 1.B: Implement a Simple Firewall Using Netfilter

🔍 Task 2: Experimenting with Stateless Firewall Rules

🔹 Task 2.A: Protecting the Router

🔹 Task 2.B: Protecting the Internal Network

🔹 Task 2.C: Protecting Internal Servers

📊 Task 3: Experimenting with Connection Tracking

🔹 Task 3.A: Experiment with the Connection Tracking

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