DHCP MAC嗅探器

该项目包含一个精简版DHCP数据包嗅探器，可被动监听网络中的DHCP流量，提取客户端MAC地址，并通过网页界面展示，每个MAC地址均可一键复制。

⚠️ 该脚本不会响应DHCP请求，仅进行观察记录。

运行要求

1. Python 3.8及以上版本
2. 管理员/root权限（数据包捕获必需）
3. Windows系统需安装Npcap (https://npcap.com/) ，安装时务必勾选 "Install Npcap in WinPcap API-compatible Mode" 选项

安装Python依赖：

pip install -r requirements.txt

使用方法

# 在所有网络接口上运行，并通过http://localhost:8080提供网页界面
python dhcp_mac_sniffer.py

# 指定特定网接口和自定义端口（web页面可以修改网口）
python dhcp_mac_sniffer.py --iface Ethernet --port 8080

在浏览器中访问指定地址，新监测到的MAC地址将自动显示。点击任意地址旁的复制按钮即可将其拷贝至剪贴板。

工作原理

• 脚本使用Scapy进行数据包嗅探，BPF过滤器设置为：udp and (port 67 or port 68)
• 当检测到包含DHCP层的数据包时，从以太网头部提取源MAC地址并存储
• 轻量级Flask服务器托管一个HTML页面，该页面通过AJAX定期获取当前MAC地址列表

由于程序仅监听而不发送数据，因此不会与客户端设备建立任何通信连接。

DHCP MAC Sniffer

This project contains a minimal DHCP packet sniffer that passively listens for DHCP traffic on your network, extracts client MAC addresses, and presents them in a web UI where each MAC address can be copied with a single click.

⚠️ The script does not respond to DHCP requests; it only observes them.

Prerequisites

1. Python 3.8+
2. Administrator / root privileges (required for packet capturing)
3. On Windows, install Npcap (https://npcap.com/) and be sure to enable the option “Install Npcap in WinPcap API-compatible Mode”.

Install Python dependencies:

pip install -r requirements.txt

Usage

# Run on all interfaces and serve UI on http://localhost:8080
python dhcp_mac_sniffer.py

# Specify a particular interface and custom port
python dhcp_mac_sniffer.py --iface Ethernet --port 8080

Open your browser to the indicated address; newly observed MAC addresses will appear automatically. Click Copy next to any address to copy it to your clipboard.

How it works

• The script uses Scapy to sniff packets with a BPF filter: udp and (port 67 or port 68).
• When a packet containing a DHCP layer is seen, the source MAC address is extracted from the Ethernet header and stored.
• A lightweight Flask server hosts a small HTML page that periodically fetches the current list of MAC addresses via AJAX.

Since the program only listens and never transmits, no communication is established with the client devices.