Duplicate Packet Generator for UDP and ICMP on Linux Kernel

Overview

This repository contains code to create duplicate packets for UDP and ICMP protocols within the Linux kernel. The modified kernel code sends duplicate packets over a specified interface.

Prerequisites

• Operating System: Ubuntu 22.04
• Kernel Version: 5.15.0

Installation Instructions

1. Install the Required Kernel Version

Ensure you have the correct kernel version installed:

sudo apt install linux-image-5.15.0-50-generic

2. Place the Modified Files

Copy the modified source files (udp.c, ping.c, etc.) into the kernel source directory:

<kernel_source_directory>/net/ipv4/

3. Configure Interface Names and IP Addresses

The code sends packets over the default interface. Update the interface names and IP addresses in the following files:

• In udp.c:

static int udp_send_skb(struct sk_buff *skb, struct flowi4 *fl4, struct inet_cork *cork)

Modify the condition to match your second interface IP and the multicast IP for the duplicate packet:

if (iph->saddr == in_aton("SECOND_INTERFACE_IP") && iph->daddr == in_aton("MULTICAST_IP_FOR_DUPLICATE"))

• In ping.c:

Set the device name and destination IP address:

dev = dev_get_by_name(&init_net, "INTERFACE_NAME");
iph->daddr = in_aton("SECOND_INTERFACE_IP");

Note: Replace the placeholders with your actual network configurations:

SECOND_INTERFACE_IP: The IP address of your second interface.

MULTICAST_IP_FOR_DUPLICATE: The multicast IP for the duplicate packet.

INTERFACE_NAME: The name of your network interface (e.g., eth1, wlp2s2).

4. Compile the Kernel

make -j$(nproc)
sudo make modules_install
sudo make install
sudo update-grub
sudo reboot