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<ol class="chapter"><li class="chapter-item expanded affix "><a href="../https://github.com/eunomia-bpf/bpf-developer-tutorial.html">https://github.com/eunomia-bpf/bpf-developer-tutorial</a></li><li class="chapter-item expanded affix "><li class="part-title">目录</li><li class="chapter-item expanded "><a href="../0-introduce/index.html"><strong aria-hidden="true">1.</strong> 介绍 eBPF 的基本概念、常见的开发工具</a></li><li class="chapter-item expanded "><a href="../1-helloworld/index.html"><strong aria-hidden="true">2.</strong> eBPF Hello World，基本框架和开发流程</a></li><li class="chapter-item expanded "><a href="../2-kprobe-unlink/index.html"><strong aria-hidden="true">3.</strong> 使用 kprobe 监测捕获 unlink 系统调用</a></li><li class="chapter-item expanded "><a href="../3-fentry-unlink/index.html"><strong aria-hidden="true">4.</strong> 使用 fentry 监测捕获 unlink 系统调用</a></li><li class="chapter-item expanded "><a href="../4-opensnoop/index.html"><strong aria-hidden="true">5.</strong> 捕获进程打开文件的系统调用集合，使用全局变量过滤进程 pid</a></li><li class="chapter-item expanded "><a href="../5-uprobe-bashreadline/index.html"><strong aria-hidden="true">6.</strong> 使用 uprobe 捕获 bash 的 readline 函数调用</a></li><li class="chapter-item expanded "><a href="../6-sigsnoop/index.html"><strong aria-hidden="true">7.</strong> 捕获进程发送信号的系统调用集合，使用 hash map 保存状态</a></li><li class="chapter-item expanded "><a href="../7-execsnoop/index.html"><strong aria-hidden="true">8.</strong> 捕获进程执行/退出时间，通过 perf event array 向用户态打印输出</a></li><li class="chapter-item expanded "><a href="../8-exitsnoop/index.html"><strong aria-hidden="true">9.</strong> 使用 exitsnoop 监控进程退出事件，使用 ring buffer 向用户态打印输出</a></li><li class="chapter-item expanded "><a href="../9-runqlat/index.html"><strong aria-hidden="true">10.</strong> 一个 Linux 内核 BPF 程序，通过柱状图来总结调度程序运行队列延迟，显示任务等待运行在 CPU 上的时间长度</a></li><li class="chapter-item expanded "><a href="../10-hardirqs/index.html"><strong aria-hidden="true">11.</strong> 使用 hardirqs 或 softirqs 捕获中断事件</a></li><li class="chapter-item expanded "><a href="../11-bootstrap/index.html"><strong aria-hidden="true">12.</strong> 使用 bootstrap 开发用户态程序并跟踪 exec() 和 exit() 系统调用</a></li><li class="chapter-item expanded "><a href="../13-tcpconnlat/index.html"><strong aria-hidden="true">13.</strong> 使用 libbpf-bootstrap 开发程序统计 TCP 连接延时</a></li><li class="chapter-item expanded "><a href="../14-tcpstates/index.html"><strong aria-hidden="true">14.</strong> 使用 libbpf-bootstrap 记录 TCP 连接状态与 TCP RTT</a></li><li class="chapter-item expanded "><a href="../15-javagc/index.html"><strong aria-hidden="true">15.</strong> 使用 USDT 捕获用户态 Java GC 事件耗时</a></li><li class="chapter-item expanded "><a href="../16-memleak/index.html"><strong aria-hidden="true">16.</strong> 编写 eBPF 程序 Memleak 监控内存泄漏</a></li><li class="chapter-item expanded "><a href="../17-biopattern/index.html"><strong aria-hidden="true">17.</strong> 编写 eBPF 程序 Biopattern 统计随机/顺序磁盘 I/O</a></li><li class="chapter-item expanded "><a href="../18-further-reading/index.html"><strong aria-hidden="true">18.</strong> 更多的参考资料：论文列表、项目、博客等等</a></li><li class="chapter-item expanded "><a href="../19-lsm-connect/index.html"><strong aria-hidden="true">19.</strong> 使用 LSM 进行安全检测防御</a></li><li class="chapter-item expanded "><a href="../20-tc/index.html"><strong aria-hidden="true">20.</strong> 使用 eBPF 进行 tc 流量控制</a></li><li class="chapter-item expanded affix "><li class="part-title">eBPF 高级特性与进阶主题</li><li class="chapter-item expanded "><a href="../22-android/index.html"><strong aria-hidden="true">21.</strong> 在 Android 上使用 eBPF 程序</a></li><li class="chapter-item expanded "><a href="../23-http/index.html"><strong aria-hidden="true">22.</strong> 使用 eBPF socket filter 或 syscall tracepoint 追踪 HTTP 请求等七层协议</a></li><li class="chapter-item expanded "><a href="../30-sslsniff/index.html"><strong aria-hidden="true">23.</strong> 使用 uprobe 捕获多种库的 SSL/TLS 明文数据</a></li><li class="chapter-item expanded "><a href="../29-sockops/index.html"><strong aria-hidden="true">24.</strong> 使用 sockops 加速网络请求转发</a></li><li class="chapter-item expanded "><a href="../24-hide/index.html"><strong aria-hidden="true">25.</strong> 使用 eBPF 隐藏进程或文件信息</a></li><li class="chapter-item expanded "><a href="../25-signal/index.html"><strong aria-hidden="true">26.</strong> 使用 bpf_send_signal 发送信号终止进程</a></li><li class="chapter-item expanded "><a href="../26-sudo/index.html" class="active"><strong aria-hidden="true">27.</strong> 使用 eBPF 添加 sudo 用户</a></li><li class="chapter-item expanded "><a href="../27-replace/index.html"><strong aria-hidden="true">28.</strong> 使用 eBPF 替换任意程序读取或写入的文本</a></li><li class="chapter-item expanded "><a href="../28-detach/index.html"><strong aria-hidden="true">29.</strong> BPF的生命周期：使用 Detached 模式在用户态应用退出后持续运行 eBPF 程序</a></li><li class="chapter-item expanded "><a href="../30-sslsniff/index.html"><strong aria-hidden="true">30.</strong> 使用 eBPF 用户态捕获多种库的 SSL/TLS 明文数据</a></li><li class="chapter-item expanded affix "><li class="part-title">bcc 教程与文档</li><li class="chapter-item expanded "><a href="../bcc-documents/kernel-versions.html"><strong aria-hidden="true">31.</strong> BPF Features by Linux Kernel Version</a></li><li class="chapter-item expanded "><a href="../bcc-documents/kernel_config.html"><strong aria-hidden="true">32.</strong> Kernel Configuration for BPF Features</a></li><li class="chapter-item expanded "><a href="../bcc-documents/reference_guide.html"><strong aria-hidden="true">33.</strong> bcc Reference Guide</a></li><li class="chapter-item expanded "><a href="../bcc-documents/special_filtering.html"><strong aria-hidden="true">34.</strong> Special Filtering</a></li><li class="chapter-item expanded "><a href="../bcc-documents/tutorial.html"><strong aria-hidden="true">35.</strong> bcc Tutorial</a></li><li class="chapter-item expanded "><a href="../bcc-documents/tutorial_bcc_python_developer.html"><strong aria-hidden="true">36.</strong> bcc Python Developer Tutorial</a></li></ol>
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<h1 id="使用-ebpf-添加-sudo-用户"><a class="header" href="#使用-ebpf-添加-sudo-用户">使用 eBPF 添加 sudo 用户</a></h1>
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<p>编译：</p>
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<pre><code class="language-bash">make
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</code></pre>
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<p>使用方式：</p>
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<pre><code class="language-sh">sudo ./sudoadd --username lowpriv-user
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</code></pre>
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<p>这个程序允许一个通常权限较低的用户使用 <code>sudo</code> 成为 root。</p>
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<p>它通过拦截 <code>sudo</code> 读取 <code>/etc/sudoers</code> 文件，并将第一行覆盖为 <code><username> ALL=(ALL:ALL) NOPASSWD:ALL #</code> 的方式工作。这欺骗了 sudo，使其认为用户被允许成为 root。其他程序如 <code>cat</code> 或 <code>sudoedit</code> 不受影响，所以对于这些程序来说，文件未改变，用户并没有这些权限。行尾的 <code>#</code> 确保行的其余部分被当作注释处理，因此不会破坏文件的逻辑。</p>
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<h2 id="参考资料"><a class="header" href="#参考资料">参考资料</a></h2>
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<ul>
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<li><a href="https://github.com/pathtofile/bad-bpf">https://github.com/pathtofile/bad-bpf</a></li>
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