Wake-on-LAN (WOL) 技术深度解析：从协议到驱动的完整实现

// drivers/net/ethernet/intel/e1000e/netdev.c
static void __e1000_shutdown(struct pci_dev *pdev, bool runtime)
{
    struct e1000_adapter *adapter = pci_get_drvdata(pdev);
    struct e1000_hw *hw = &adapter->hw;

    if (adapter->wol) {
        // 配置 Wake Up Control Register (WUFC)
        ew32(WUFC, E1000_WUFC_MAG);  // 0x0002: Magic Packet Enable

        // 设置 PCI Power Management Capability
        pci_enable_wake(pdev, PCI_D3hot, 1);
        pci_enable_wake(pdev, PCI_D3cold, 1);
    } else {
        ew32(WUFC, 0);  // 完全禁用唤醒
    }

    pci_set_power_state(pdev, PCI_D3hot);
}

// net/core/ethtool.c
static int ethtool_set_wol(struct net_device *dev, char __user *useraddr)
{
    struct ethtool_wolinfo wol;

    if (copy_from_user(&wol, useraddr, sizeof(wol)))
        return -EFAULT;

    // wol.wolopts = WAKE_MAGIC (0x20)
    return dev->ethtool_ops->set_wol(dev, &wol);
}

#!/usr/bin/env python3
import socket
import struct

def send_magic_packet(mac_address: str, broadcast='255.255.255.255', port=9):
    """
    发送 WOL 魔术包

    Args:
        mac_address: 目标 MAC 地址 (格式: "AA:BB:CC:DD:EE:FF" 或 "AA-BB-CC-DD-EE-FF")
        broadcast: 广播地址 (同网段用 255.255.255.255，跨网段用定向广播如 192.168.1.255)
        port: UDP 端口 (通常为 7 或 9)
    """
    # 规范化 MAC 地址
    mac = mac_address.replace(':', '').replace('-', '')
    if len(mac) != 12:
        raise ValueError(f"Invalid MAC address: {mac_address}")

    # 构造魔术包：6 字节 0xFF + 16 次 MAC 地址
    magic_packet = b'\xFF' * 6 + bytes.fromhex(mac) * 16

    # 发送 UDP 广播包
    with socket.socket(socket.AF_INET, socket.SOCK_DGRAM) as sock:
        sock.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
        sock.sendto(magic_packet, (broadcast, port))
        print(f"✓ Magic packet sent to {mac_address} via {broadcast}:{port}")

# 使用示例
if __name__ == '__main__':
    send_magic_packet('AA:BB:CC:DD:EE:FF')

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <sys/socket.h>

#define MAGIC_PACKET_SIZE 102

int send_wol(const char *mac_str, const char *broadcast_ip) {
    unsigned char mac[6];
    unsigned char packet[MAGIC_PACKET_SIZE];

    // 解析 MAC 地址
    if (sscanf(mac_str, "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx",
               &mac[0], &mac[1], &mac[2], &mac[3], &mac[4], &mac[5]) != 6) {
        fprintf(stderr, "Invalid MAC address format\n");
        return -1;
    }

    // 构造魔术包
    memset(packet, 0xFF, 6);  // 前 6 字节为 0xFF
    for (int i = 0; i < 16; i++) {
        memcpy(packet + 6 + i * 6, mac, 6);  // 重复 MAC 地址 16 次
    }

    // 创建 UDP socket
    int sockfd = socket(AF_INET, SOCK_DGRAM, 0);
    if (sockfd < 0) {
        perror("socket");
        return -1;
    }

    // 启用广播
    int broadcast_enable = 1;
    if (setsockopt(sockfd, SOL_SOCKET, SO_BROADCAST,
                   &broadcast_enable, sizeof(broadcast_enable)) < 0) {
        perror("setsockopt");
        close(sockfd);
        return -1;
    }

    // 设置目标地址
    struct sockaddr_in addr;
    memset(&addr, 0, sizeof(addr));
    addr.sin_family = AF_INET;
    addr.sin_port = htons(9);
    addr.sin_addr.s_addr = inet_addr(broadcast_ip);

    // 发送魔术包
    if (sendto(sockfd, packet, MAGIC_PACKET_SIZE, 0,
               (struct sockaddr *)&addr, sizeof(addr)) < 0) {
        perror("sendto");
        close(sockfd);
        return -1;
    }

    printf("Magic packet sent to %s\n", mac_str);
    close(sockfd);
    return 0;
}

int main(int argc, char *argv[]) {
    if (argc != 3) {
        fprintf(stderr, "Usage: %s <MAC> <broadcast_ip>\n", argv[0]);
        fprintf(stderr, "Example: %s AA:BB:CC:DD:EE:FF 192.168.1.255\n", argv[0]);
        return 1;
    }

    return send_wol(argv[1], argv[2]);
}

#!/bin/bash
# wol.sh - Wake-on-LAN wrapper script

MAC=$1
BROADCAST=${2:-255.255.255.255}

if [[ ! $MAC =~ ^([0-9A-Fa-f]{2}[:-]){5}([0-9A-Fa-f]{2})$ ]]; then
    echo "Error: Invalid MAC address format"
    echo "Usage: $0 <MAC> [broadcast_ip]"
    exit 1
fi

# 方法1：使用 wakeonlan 工具
if command -v wakeonlan &> /dev/null; then
    wakeonlan -i $BROADCAST $MAC
    exit 0
fi

# 方法2：使用 etherwake（需要 root）
if command -v etherwake &> /dev/null; then
    sudo etherwake -i eth0 $MAC
    exit 0
fi

# 方法3：使用 socat（更底层）
if command -v socat &> /dev/null; then
    MAC_HEX=$(echo $MAC | tr -d ':' | tr -d '-')
    PAYLOAD="\xFF\xFF\xFF\xFF\xFF\xFF$(printf "${MAC_HEX}%.0s" {1..16})"
    echo -ne $PAYLOAD | socat - UDP-DATAGRAM:$BROADCAST:9,broadcast
    exit 0
fi

echo "Error: No WOL tool found. Install: wakeonlan, etherwake, or socat"
exit 1

def send_secure_magic_packet(mac_address: str, password: str, broadcast='255.255.255.255'):
    """发送带密码的魔术包（SecureOn）"""
    mac = mac_address.replace(':', '').replace('-', '')
    pwd = password.replace(':', '').replace('-', '')

    if len(pwd) != 12:
        raise ValueError("Password must be 6 bytes (12 hex chars)")

    magic_packet = b'\xFF' * 6 + bytes.fromhex(mac) * 16 + bytes.fromhex(pwd)

    with socket.socket(socket.AF_INET, socket.SOCK_DGRAM) as sock:
        sock.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
        sock.sendto(magic_packet, (broadcast, 9))

# 清除现有规则
sudo iptables -F INPUT

# 允许来自管理网段的 UDP/9
sudo iptables -A INPUT -p udp --dport 9 -s 192.168.1.0/24 -j ACCEPT

# 阻止其他来源的魔术包
sudo iptables -A INPUT -p udp --dport 9 -j DROP

# 保存规则
sudo iptables-save > /etc/iptables/rules.v4