VM with pre-installed packages

You can download a Qemu VM disk image and can host it on your machine for the sake of this tutorial. This VM is pre-insalled with all the dependencies and the repo is already present in the home directory. You can download the image using the following command, but only on IIT Bombay Internal Network:

$ curl http://charles_02.cse.iitb.ac.in/ubuntu22.04.qcow2 --output ubuntu22.04.qcow2

NOTE: Since, this a disk image the size of this file is 20GB.

Manual installation of dependencies

Before you can start completing the steps in this XDP-tutorial, go though this document and install the needed software packages.

The main dependencies are libbpf, llvm, clang and libelf. LLVM+clang compiles our restricted-C programs into BPF-byte-code, which is stored in an ELF object file (libelf), that is loaded by libbpf into the kernel via the bpf syscall. Some of the lessons also use the perf utility to track the kernel behaviour through tracepoints.

The Makefiles in this repo will try to detect if you are missing some dependencies, and give you some pointers.

Packages on Ubuntu

On Debian and Ubuntu installations, install the dependencies like this:

$ sudo apt install clang llvm libelf-dev libpcap-dev gcc-multilib build-essential libbpf-dev

Kernel headers dependency

The Linux kernel provides a number of header files, which are usually installed in /usr/include/linux. The different Linux distributions usually provide a software package with these headers.

Some of the header files (we depend on) are located in the kernel tree under include/uapi/linux/ (e.g. include/uapi/linux/bpf.h), but you should not include those files as they go through a conversion process when exported/installed into distros’ /usr/include/linux directory. In the kernel git tree you can run the command: make headers_install which will create a lot of headers files in directory “usr/”.

For now, this tutorial depends on kernel headers package provided by your distro.

$ sudo apt install linux-headers-$(uname -r)

Recommended tools

The bpftool is the recommended tool for inspecting BPF programs running on your system. It also offers simple manipulation of eBPF programs and maps. In our tutorials, we will be loading our programs using bpftool. The bpftool is part of the Linux kernel tree under tools/bpf/bpftool/, but some Linux distributions also ship the tool as a software package. For installing bpftool on Ubuntu use the following command:

$ sudo apt install linux-tools-common linux-tools-generic