Add more XDP related blogs (#135)

* add setup

* update

* fix code

* move to dir

* fix code

* update the code

* update code of 42

* update 21

* update

* fix linter issues and add xdp in rust

* update the docker file

* fix CI

* fix kernel code

* update

* update

* add guidline

Author: yunwei37

README.md

@@ -1,6 +1,7 @@
 # eBPF Developer Tutorial: Learning eBPF Step by Step with Examples
 
 [![CI](https://github.com/eunomia-bpf/bpf-developer-tutorial/actions/workflows/main.yml/badge.svg)](https://github.com/eunomia-bpf/bpf-developer-tutorial/actions/workflows/main.yml)
+[![Test and trigger downstream tutorial sync](https://github.com/eunomia-bpf/bpf-developer-tutorial/actions/workflows/trigger-sync.yml/badge.svg)](https://github.com/eunomia-bpf/bpf-developer-tutorial/actions/workflows/trigger-sync.yml)
 
 [GitHub](https://github.com/eunomia-bpf/bpf-developer-tutorial)
 [Gitee Mirror](https://gitee.com/yunwei37/bpf-developer-tutorial)
@@ -58,14 +59,16 @@ Android:
 Networking:
 
 - [Accelerating network request forwarding using sockops](src/29-sockops/README.md)
+- [Capturing TCP Information with XDP](src/41-xdp-tcpdump/README.md)
+- [XDP Load Balancer](src/42-xdp-loadbalancer/README.md)
 
 tracing:
 
 - [Tracing HTTP requests or other layer-7 protocols using eBPF socket filter or syscall trace](src/23-http/README.md)
 - [Capturing Plain Text Data of Various Libraries' SSL/TLS Using uprobe](src/30-sslsniff/README.md)
 - [Using eBPF to Trace Go Routine States](src/31-goroutine/README.md)
 - [Measuring Function Latency with eBPF](src/33-funclatency/README.md)
-- [Use uprobe to trace Rust programs](src/37-uprobe-rust/README.md)
+- [Use Uprobe to trace Rust programs](src/37-uprobe-rust/README.md)
 - [Using eBPF to Trace Nginx Requests](src/39-nginx/README.md)
 - [Using eBPF to Trace MySQL Queries](src/40-mysql)
 
@@ -89,9 +92,9 @@ Continuously updating...
 
 ## Why write this tutorial?
 
-In the process of learning eBPF, we have been inspired and helped by the [bcc python developer tutorial](src/bcc-documents/tutorial_bcc_python_developer.md). However, from the current perspective, using libbpf to develop eBPF applications is a relatively better choice. However, there seems to be few tutorials that focus on eBPF development based on libbpf and BPF CO-RE, introducing it through examples and tools. Therefore, we initiated this project, adopting a similar organization method as the bcc python developer tutorial, but using CO-RE's libbpf for development.
+In the process of learning eBPF, we have been inspired and helped by the [bcc python developer tutorial](src/bcc-documents/tutorial_bcc_python_developer.md). However, from the current perspective, using `libbpf` to develop eBPF applications is a relatively better choice.
 
-This project is mainly based on [libbpf-bootstrap](https://github.com/libbpf/libbpf-bootstrap) and [eunomia-bpf](https://github.com/eunomia-bpf/eunomia-bpf) frameworks, and uses eunomia-bpf to help simplify the development of some user-space libbpf eBPF code, allowing developers to focus on kernel-space eBPF code development.
+This project is mainly based on [libbpf](https://github.com/libbpf/libbpf) frameworks.
 
 > - We also provide a small tool called GPTtrace, which uses ChatGPT to automatically write eBPF programs and trace Linux systems through natural language descriptions. This tool allows you to interactively learn eBPF programs: [GPTtrace](https://github.com/eunomia-bpf/GPTtrace)
 > - Feel free to raise any questions or issues related to eBPF learning, or bugs encountered in practice, in the issue or discussion section of this repository. We will do our best to help you!
@@ -145,65 +148,18 @@ TIME     COMM             TID     LAT(us)
 
 ![docker](imgs/docker.png)
 
-## build 
+## build
 
 The example of local compilation is shown as follows:
 
 ```shell
-$ git clone https://github.com/eunomia-bpf/bpf-developer-tutorial.git
-$ cd bpf-developer-tutorial
-$ git submodule update --init --recursive # Synchronize submodule
-$ cd src/24-hide
-$ make
+git clone https://github.com/eunomia-bpf/bpf-developer-tutorial.git
+cd bpf-developer-tutorial
+git submodule update --init --recursive # Synchronize submodule
+cd src/24-hide
+make
 ```
 
-## Why do we need tutorials based on libbpf and BPF CO-RE?
+## LICENSE
 
-> In history, when it comes to developing a BPF application, one could choose the BCC framework to load the BPF program into the kernel when implementing various BPF programs for Tracepoints. BCC provides a built-in Clang compiler that can compile BPF code at runtime and customize it into a program that conforms to a specific host kernel. This is the only way to develop maintainable BPF applications under the constantly changing internal kernel environment. The portability of BPF and the introduction of CO-RE are detailed in the article "BPF Portability and CO-RE", explaining why BCC was the only viable option before and why libbpf is now considered a better choice. Last year, Libbpf saw significant improvements in functionality and complexity, eliminating many differences with BCC (especially for Tracepoints applications) and adding many new and powerful features that BCC does not support (such as global variables and BPF skeletons)
->
-> Admittedly, BCC does its best to simplify the work of BPF developers, but sometimes it also increases the difficulty of problem localization and fixing while providing convenience. Users must remember its naming conventions and the autogenerated structures for Tracepoints, and they must rely on rewriting this code to read kernel data and access kprobe parameters. When using BPF maps, it is necessary to write half-object-oriented C code that does not completely match what happens in the kernel. Furthermore, BCC leads to the writing of a large amount of boilerplate code in user space, with manually configuring the most trivial parts.
->
-> As mentioned above, BCC relies on runtime compilation and embeds a large LLVM/Clang library, which creates certain gaps between BCC and an ideal usage scenario:
->
-> - High resource utilization (memory and CPU) at compile time, which may interfere with the main process in busy servers.
-> - It relies on the kernel header package and needs to be installed on each target host. Even so, if certain kernel contents are not exposed through public header files, type definitions need to be copied and pasted into the BPF code to achieve the purpose.
-> - Even the smallest compile-time errors can only be detected at runtime, followed by recompiling and restarting the user-space application. This greatly affects the iteration time of development (and increases frustration...).
->
-> Libbpf + BPF CO-RE (Compile Once - Run Everywhere) takes a different approach, considering BPF programs as normal user-space programs: they only need to be compiled into small binaries that can be deployed on target hosts without modification. libbpf acts as a loader for BPF programs, responsible for configuration work (relocating, loading, and verifying BPF programs, creating BPF maps, attaching to BPF hooks, etc.), and developers only need to focus on the correctness and performance of BPF programs. This approach minimizes overhead, eliminates dependencies, and improves the overall developer experience.
->
-> In terms of API and code conventions, libbpf adheres to the philosophy of "least surprise", where most things need to be explicitly stated: no header files are implied, and no code is rewritten. Most monotonous steps can be eliminated using simple C code and appropriate auxiliary macros. In addition, what users write is the content that needs to be executed, and the structure of BPF applications is one-to-one, finally verified and executed by the kernel.
-
-Reference: [BCC to Libbpf Conversion Guide (Translation) - Deep Dive into eBPF](https://www.ebpf.top/post/bcc-to-libbpf-guid/)
-
-## eunomia-bpf
-
-[eunomia-bpf](https://github.com/eunomia-bpf/eunomia-bpf) is an open-source eBPF dynamic loading runtime and development toolkit designed to simplify the development, building, distribution, and execution of eBPF programs. It is based on the libbpf CO-RE lightweight development framework.
-
-With eunomia-bpf, you can:
-
-- Write only the libbpf kernel mode code when writing eBPF programs or tools, automatically retrieving kernel mode export information.
-- Use Wasm to develop eBPF user mode programs, controlling the entire eBPF program loading and execution, as well as handling related data within the WASM virtual machine.
-- eunomia-bpf can package pre-compiled eBPF programs into universal JSON or WASM modules for distribution across architectures and kernel versions, allowing dynamic loading and execution without the need for recompilation.
-
-eunomia-bpf consists of a compilation toolchain and a runtime library. Compared to traditional frameworks like BCC and native libbpf, it greatly simplifies the development process of eBPF programs, where in most cases, only the kernel mode code needs to be written to easily build, package, and publish complete eBPF applications. At the same time, the kernel mode eBPF code guarantees compatibility with mainstream development frameworks such as libbpf, libbpfgo, libbpf-rs, and more. When user mode code needs to be written, multiple languages can be used with the help of Webassembly. Compared to script tools like bpftrace, eunomia-bpf maintains similar convenience, while not being limited to trace scenarios and can be used in various other fields such as networking and security.
-
-- eunomia-bpf project GitHub address: <https://github.com/eunomia-bpf/eunomia-bpf>
-- gitee mirror: <https://gitee.com/anolis/eunomia>
-
-## Let ChatGPT Help Us
-
-This tutorial uses ChatGPT to learn how to write eBPF programs. At the same time, we try to teach ChatGPT how to write eBPF programs. The general steps are as follows:
-
-1. Teach it the basic knowledge of eBPF programming.
-2. Show it some cases: hello world, basic structure of eBPF programs, how to use eBPF programs for tracing, and let it start writing tutorials.
-3. Manually adjust the tutorials and correct errors in the code and documents.
-4. Feed the modified code back to ChatGPT for further learning.
-5. Try to make ChatGPT generate eBPF programs and corresponding tutorial documents automatically! For example:
-
-![ebpf-chatgpt-signal](imgs/ebpf-chatgpt-signal.png)
-
-The complete conversation log can be found here: [ChatGPT.md](ChatGPT.md)
-
-We have also built a demo of a command-line tool. Through training in this tutorial, it can automatically write eBPF programs and trace Linux systems using natural language descriptions: <https://github.com/eunomia-bpf/GPTtrace>
-
-![ebpf-chatgpt-signal](https://github.com/eunomia-bpf/GPTtrace/blob/main/doc/result.gif)
+MIT

src/0-introduce/README.md

@@ -61,12 +61,10 @@ Linux 内核的主要目的是抽象出硬件或虚拟硬件，并提供一个
 
 了解并尝试一下 eBPF 开发框架：
 
-- bpftrace 教程，对于最简单的应用来说，bpftrace 可能是最方便的：https://eunomia.dev/zh/tutorials/bpftrace-tutorial/ （试试，1h）
+- bpftrace 教程，对于最简单的应用来说，bpftrace 可能是最方便的：<https://eunomia.dev/zh/tutorials/bpftrace-tutorial/> （试试，1h）
 - BCC 开发各类小工具的例子：<https://github.com/iovisor/bcc/blob/master/docs/tutorial_bcc_python_developer.md> （跑一遍，3-4h）
 - libbpf 的一些例子：<https://github.com/libbpf/libbpf-bootstrap> （选感兴趣的运行一下，并阅读一下源代码，2h）
-- 基于 libbpf 和 eunomia-bpf 的教程：<https://github.com/eunomia-bpf/bpf-developer-tutorial> （阅读 1-10 的部分，3-4h）
-
-其他开发框架：Go 语言或者 Rust 语言，请自行搜索并且尝试（0-2h）
+- 基于 C 语言 libbpf, Go 语言或者 Rust 语言和 eunomia-bpf 的教程：<https://github.com/eunomia-bpf/bpf-developer-tutorial> （阅读 1-20 的部分，3-8h）
 
 有任何问题或者想了解的东西，不管是不是和本项目相关，都可以在本项目的 discussions 里面开始讨论。
 
@@ -147,17 +145,14 @@ eBPF Go 库提供了一个通用的 eBPF 库，它解耦了获取 eBPF 字节码
 
 ### eunomia-bpf
 
-开发、构建和分发 eBPF 一直以来都是一个高门槛的工作，使用 BCC、bpftrace 等工具开发效率高、可移植性好，但是分发部署时需要安装 LLVM、Clang 等编译环境，每次运行的时候执行本地或远程编译过程，资源消耗较大；使用原生的 CO-RE libbpf 时又需要编写不少用户态加载代码来帮助 eBPF 程序正确加载和从内核中获取上报的信息，同时对于 eBPF 程序的分发、管理也没有很好地解决方案。
-
 [eunomia-bpf](https://github.com/eunomia-bpf/eunomia-bpf) 是一个开源的 eBPF 动态加载运行时和开发工具链，是为了简化 eBPF 程序的开发、构建、分发、运行而设计的，基于 libbpf 的 CO-RE 轻量级开发框架。
 
 使用 eunomia-bpf ，可以：
 
 - 在编写 eBPF 程序或工具时只编写内核态代码，自动获取内核态导出信息，并作为模块动态加载；
-- 使用 WASM 进行用户态交互程序的开发，在 WASM 虚拟机内部控制整个 eBPF 程序的加载和执行，以及处理相关数据；
 - eunomia-bpf 可以将预编译的 eBPF 程序打包为通用的 JSON 或 WASM 模块，跨架构和内核版本进行分发，无需重新编译即可动态加载运行。
 
-eunomia-bpf 由一个编译工具链和一个运行时库组成, 对比传统的 BCC、原生 libbpf 等框架，大幅简化了 eBPF 程序的开发流程，在大多数时候只需编写内核态代码，即可轻松构建、打包、发布完整的 eBPF 应用，同时内核态 eBPF 代码保证和主流的 libbpf，libbpfgo，libbpf-rs 等开发框架的 100% 兼容性。需要编写用户态代码的时候，也可以借助 Webassembly 实现通过多种语言进行用户态开发。和 bpftrace 等脚本工具相比, eunomia-bpf 保留了类似的便捷性, 同时不仅局限于 trace 方面, 可以用于更多的场景, 如网络、安全等等。
+eunomia-bpf 由一个编译工具链和一个运行时库组成, 对比传统的 BCC、原生 libbpf 等框架，简化了 eBPF 程序的开发流程，在大多数时候只需编写内核态代码，即可轻松构建、打包、发布完整的 eBPF 应用。
 
 > - eunomia-bpf 项目 Github 地址: <https://github.com/eunomia-bpf/eunomia-bpf>
 > - gitee 镜像: <https://gitee.com/anolis/eunomia>

src/0-introduce/README_en.md

@@ -125,17 +125,14 @@ as well as the key functions used to load kernel space code. After the user-spac
 
 ### eunomia-bpf
 
-Developing, building, and distributing eBPF has always been a high-threshold task. The use of tools such as BCC and bpftrace has high development efficiency and good portability. However, when it comes to distribution and deployment, it requires the installation of LLVM, Clang, and other compilation environments, and the compilation process needs to be executed locally or remotely every time, resulting in substantial resource consumption. On the other hand, using the native CO-RE libbpf requires writing a considerable amount of user-mode loading code to help properly load eBPF programs and obtain reported information from the kernel. At the same time, there is no good solution for distributing and managing eBPF programs.
-
-[eunomia-bpf](https://github.com/eunomia-bpf/eunomia-bpf) is an open-source eBPF dynamic loading runtime and development toolchain designed to simplify the development, building, distribution, and execution of eBPF programs. It is based on the libbpf CO-RE lightweight development framework.
+[eunomia-bpf](https://github.com/eunomia-bpf/eunomia-bpf) is an open-source eBPF dynamic loading tool and development toolchain designed to simplify the development, building, distribution, and execution of eBPF programs. It is based on the libbpf CO-RE lightweight development framework.
 
 With eunomia-bpf, you can:
 
 - When writing eBPF programs or tools, only write kernel space code, automatically retrieve kernel space export information, and dynamically load it as a module.
-- Use WASM for user space interactive program development to control the loading and execution of the entire eBPF program, as well as the processing of related data inside the WASM virtual machine.
 - eunomia-bpf can package pre-compiled eBPF programs into universal JSON or WASM modules for distribution across architectures and kernel versions. They can be dynamically loaded and run without the need for recompilation.
 
-eunomia-bpf consists of a compilation toolchain and a runtime library. Compared with traditional frameworks such as BCC and native libbpf, it greatly simplifies the development process of eBPF programs. In most cases, only writing kernel space code is required to easily build, package, and publish complete eBPF applications. At the same time, kernel space eBPF code ensures 100% compatibility with mainstream development frameworks such as libbpf, libbpfgo, libbpf-rs, etc. When there is a need to write user-space code, it can also be developed in multiple languages with the help of WebAssembly. Compared with script tools such as bpftrace, eunomia-bpf retains similar convenience, while not only limited to tracing but also applicable to more scenarios, such as networking, security, etc.
+eunomia-bpf consists of a compilation toolchain and a runtime library. Compared with traditional frameworks such as BCC and native libbpf, it simplifies the development process of eBPF programs.
 
 > - eunomia-bpf project Github address: <https://github.com/eunomia-bpf/eunomia-bpf>
 > - gitee mirror: <https://gitee.com/anolis/eunomia>

src/1-helloworld/README.md

@@ -17,7 +17,7 @@
 要开发eBPF程序，您需要安装以下软件和工具：
 
 - Linux 内核：由于eBPF是内核技术，因此您需要具备较新版本的Linux内核（至少 4.8 及以上版本，建议至少在 5.15 以上），以支持eBPF功能。
-    - 建议使用最新的 Ubuntu 版本（例如 Ubuntu 23.10）以获得最佳的学习体验，较旧的内核 eBPF 功能支持可能相对不全。
+  - 建议使用最新的 Ubuntu 版本（例如 Ubuntu 23.10）以获得最佳的学习体验，较旧的内核 eBPF 功能支持可能相对不全。
 - LLVM 和 Clang：这些工具用于编译eBPF程序。安装最新版本的LLVM和Clang可以确保您获得最佳的eBPF支持。
 
 eBPF 程序主要由两部分构成：内核态部分和用户态部分。内核态部分包含 eBPF 程序的实际逻辑，用户态部分负责加载、运行和监控内核态程序。
@@ -127,7 +127,7 @@ docker run -it -v `pwd`/:/src/ ghcr.io/eunomia-bpf/ecc-`uname -m`:latest
 
 ```console
 $ sudo ./ecli run package.json
-Runing eBPF program...
+Running eBPF program...
 ```
 
 运行这段程序后，可以通过查看 /sys/kernel/debug/tracing/trace_pipe 文件来查看 eBPF 程序的输出：

src/1-helloworld/README_en.md

@@ -17,7 +17,7 @@ Before starting to write eBPF programs, we need to prepare a suitable developmen
 To develop eBPF programs, you need to install the following software and tools:
 
 - Linux kernel: Since eBPF is a kernel technology, you need to have a relatively new version of the Linux kernel (minimum version 4.8 and above, suggested version is 5.15+ or 6.2+) to support eBPF functionality.
-  - If possible, install a new version of Ubuntu (e.g. 23.10) would be better. 
+  - If possible, install a new version of Ubuntu (e.g. 23.10) would be better.
 - LLVM and Clang: These tools are used to compile eBPF programs. Installing the latest version of LLVM and Clang ensures that you get the best eBPF support.
 
 An eBPF program consists of two main parts: the kernel space part and the user space part. The kernel space part contains the actual logic of the eBPF program, while the user space part is responsible for loading, running, and monitoring the kernel space program.
@@ -58,6 +58,7 @@ eunomia-bpf compiler
 Usage: ecc [OPTIONS] <SOURCE_PATH> [EXPORT_EVENT_HEADER]
 ....
 ```
+
 Note: If you are on the aarch64 platform, please use the [ecc-aarch64](https://github.com/eunomia-bpf/eunomia-bpf/releases/latest/download/ecc-aarch64) and [ecli-aarch64](https://github.com/eunomia-bpf/eunomia-bpf/releases/latest/download/ecli-aarch64).
 
 You can also compile using the docker image: