l3-forwarding-xdp

L3-L4 XDP-based forwarding tool.

This project implements Layer 3 (IP) and Layer 4 (TCP/UDP) packet forwarding using eBPF and XDP (eXpress Data Path). It leverages the high-performance capabilities of XDP for efficient packet processing in the Linux kernel with bird or FRR.

Note: xdp-tools is highly recommended for loading and managing the XDP program.

Installation

Install the necessary dependencies using apt:

apt update
apt install clang llvm libbpf-dev libelf-dev pkg-config make git bpftool xdp-tools

Compilation

Compile the eBPF program from the source code:

clang -O2 -g -Wall -target bpf \
  -D__BPF_TRACING__ \
  -I/usr/include \
  -I/usr/include/linux \
  -c main.c -o main.o

This will generate the object file main.o which contains the compiled eBPF code.

Usage

Attach to the Interface

Load the XDP program onto a network interface (e.g., eth0):

xdp-loader load eth0 ./main.o

Check the status of loaded XDP programs:

xdp-loader status

Monitoring and Debugging

Use bpftool to inspect maps and statistics:

bpftool map show
bpftool map dump name xdp_flow_stats

These commands will display information about the eBPF maps used in the program, such as flow statistics.

Unloading the Program

To unload the XDP program from the interface:

xdp-loader unload eth0