┌──(lyshark?kali)-[~]
└─$ sudo nmap -sS 39.97.203.57
Starting Nmap 7.94SVN ( https://nmap.org ) at 2024-08-08 15:28 CST
Nmap scan report for 39.97.203.57
Host is up (0.0038s latency).
Not shown: 997 filtered tcp ports (no-response)
PORT     STATE SERVICE
80/tcp   open  http
443/tcp  open  https
1935/tcp open  rtmp

┌──(lyshark?kali)-[~]
└─$ sudo nmap -sS -v 39.97.203.57 -p 1-2000
Starting Nmap 7.94SVN ( https://nmap.org ) at 2024-08-08 15:32 CST
Scanning 39.97.203.57 [2000 ports]
Discovered open port 80/tcp on 39.97.203.57
Discovered open port 443/tcp on 39.97.203.57
Discovered open port 1935/tcp on 39.97.203.57
Completed SYN Stealth Scan at 15:32, 7.42s elapsed (2000 total ports)
Nmap scan report for 39.97.203.57
Host is up (0.0039s latency).
Not shown: 1997 filtered tcp ports (no-response)
PORT     STATE SERVICE
80/tcp   open  http
443/tcp  open  https
1935/tcp open  rtmp

#include <winsock2.h>
#include <Windows.h>
#include <pcap.h>

#pragma comment(lib,"ws2_32.lib")
#pragma comment(lib, "packet.lib")
#pragma comment(lib, "wpcap.lib")

// 以太網(wǎng)頭部結構體
struct eth_header
{
  uint8_t dest[6];   // 目的MAC地址 (6字節(jié))
  uint8_t src[6];    // 源MAC地址 (6字節(jié))
  uint16_t type;     // 以太網(wǎng)類型字段，表示上層協(xié)議 (2字節(jié))
};

// IPv4頭部結構體
struct ip_header
{
  uint8_t ihl : 4,     // 頭部長度 (4位)，表示IP頭部的長度，以32位字為單位
      version : 4; // 版本 (4位)，IPv4的版本號為4
  uint8_t tos;        // 服務類型 (1字節(jié))
  uint16_t tot_len;   // 總長度 (2字節(jié))，表示整個IP數(shù)據(jù)報的長度，以字節(jié)為單位
  uint16_t id;        // 標識 (2字節(jié))，用于標識數(shù)據(jù)報片段
  uint16_t frag_off;  // 片段偏移 (2字節(jié))，用于數(shù)據(jù)報片段
  uint8_t ttl;        // 生存時間 (1字節(jié))，表示數(shù)據(jù)報在網(wǎng)絡中的生存時間
  uint8_t protocol;   // 協(xié)議 (1字節(jié))，表示上層協(xié)議 (例如，TCP為6，UDP為17)
  uint16_t check;     // 頭部校驗和 (2字節(jié))，用于檢驗頭部的完整性
  uint32_t saddr;     // 源地址 (4字節(jié))，表示發(fā)送方的IPv4地址
  uint32_t daddr;     // 目的地址 (4字節(jié))，表示接收方的IPv4地址
};

// TCP頭部結構體
struct tcp_header
{
  uint16_t source;    // 源端口號 (2字節(jié))
  uint16_t dest;      // 目的端口號 (2字節(jié))
  uint32_t seq;       // 序號 (4字節(jié))，表示數(shù)據(jù)段的序列號
  uint32_t ack_seq;   // 確認號 (4字節(jié))，表示期望接收的下一個序列號
  uint16_t res1 : 4,  // 保留位 (4位)，通常設為0
  doff : 4,   // 數(shù)據(jù)偏移 (4位)，表示TCP頭部的長度，以32位字為單位
  fin : 1,    // FIN標志 (1位)，表示發(fā)送方?jīng)]有更多數(shù)據(jù)
  syn : 1,    // SYN標志 (1位)，表示同步序號，用于建立連接
  rst : 1,    // RST標志 (1位)，表示重置連接
  psh : 1,    // PSH標志 (1位)，表示推送數(shù)據(jù)
  ack : 1,    // ACK標志 (1位)，表示確認字段有效
  urg : 1,    // URG標志 (1位)，表示緊急指針字段有效
  res2 : 2;   // 保留位 (2位)，通常設為0
  uint16_t window;    // 窗口大小 (2字節(jié))，表示接收方的緩沖區(qū)大小
  uint16_t check;     // 校驗和 (2字節(jié))，用于檢驗TCP頭部和數(shù)據(jù)的完整性
  uint16_t urg_ptr;   // 緊急指針 (2字節(jié))，表示緊急數(shù)據(jù)的偏移量
};

unsigned short checksum(void *b, int len)
{
  unsigned short *buf = (unsigned short *)b;
  unsigned int sum = 0;
  unsigned short result;

  for (sum = 0; len > 1; len -= 2)
    sum += *buf++;
  if (len == 1)
    sum += *(unsigned char*)buf;
  sum = (sum >> 16) + (sum & 0xFFFF);
  sum += (sum >> 16);
  result = ~sum;
  return result;
}

// 枚舉當前網(wǎng)卡
int EnumAdapters()
{
  pcap_if_t *allAdapters;
  pcap_if_t *ptr;
  int index = 0;
  char errbuf[PCAP_ERRBUF_SIZE];

  // 獲取本地機器設備列表
  if (pcap_findalldevs_ex(PCAP_SRC_IF_STRING, NULL, &allAdapters, errbuf) != -1)
  {
    // 打印網(wǎng)卡信息列表
    for (ptr = allAdapters; ptr != NULL; ptr = ptr->next)
    {
      ++index;
      if (ptr->description)
      {
        printf("[ %d ] \t [ %s ] \n", index - 1, ptr->description);
      }
    }
  }

  pcap_freealldevs(allAdapters);
  return index;
}

// 根據(jù)編號綁定到對應網(wǎng)卡
pcap_t* BindAdapters(int nChoose)
{
  pcap_if_t *adapters, *temp_adapter;
  char errbuf[PCAP_ERRBUF_SIZE];
  pcap_t *handle = NULL;

  if (pcap_findalldevs_ex(PCAP_SRC_IF_STRING, NULL, &adapters, errbuf) == -1)
  {
    return NULL;
  }

  // 遍歷找到指定的網(wǎng)卡
  temp_adapter = adapters;
  for (int x = 0; x < nChoose - 1 && temp_adapter != NULL; ++x)
  {
    temp_adapter = temp_adapter->next;
  }

  // 若找不到綁定設備則釋放句柄
  if (temp_adapter == NULL)
  {
    pcap_freealldevs(adapters);
    return NULL;
  }

  // 打開指定的網(wǎng)卡
  handle = pcap_open_live(temp_adapter->name, 65534, PCAP_OPENFLAG_PROMISCUOUS, 1000, errbuf);
  if (handle == NULL)
  {
    pcap_freealldevs(adapters);
    return NULL;
  }

  pcap_freealldevs(adapters);
  return handle;
}

// 網(wǎng)絡數(shù)據(jù)包回調函數(shù)
void packet_handler(u_char *param, const struct pcap_pkthdr *header, const u_char *pkt_data)
{
  // 打印數(shù)據(jù)包長度
  printf("數(shù)據(jù)包長度：%d\n", header->len);

  // 以太網(wǎng)頭部
  struct eth_header *eth = (struct eth_header *)(pkt_data);

  // 檢查以太網(wǎng)類型是否為 IP（0x0800）
  if (ntohs(eth->type) == 0x0800)
  {
    // IP 頭部
    struct ip_header *iph = (struct ip_header *)(pkt_data + sizeof(struct eth_header));

    // 打印 IP 頭部信息
    printf("IP 版本: %d | ", iph->version);
    printf("IP 頭長度: %d | ", iph->ihl * 4);
    printf("源IP地址: %s | ", inet_ntoa(*(struct in_addr *)&iph->saddr));
    printf("目標IP地址: %s\n", inet_ntoa(*(struct in_addr *)&iph->daddr));

    // 檢查協(xié)議是否為 TCP（6）
    if (iph->protocol == 6)
    {
      // TCP 頭部
      struct tcp_header *tcph = (struct tcp_header *)(pkt_data + sizeof(struct eth_header) + iph->ihl * 4);

      // 打印 TCP 頭部信息
      printf("源端口: %d | ", ntohs(tcph->source));
      printf("目標端口: %d | ", ntohs(tcph->dest));
      printf("序列號: %u | ", ntohl(tcph->seq));
      printf("確認號: %u | ", ntohl(tcph->ack_seq));
      printf("包頭長度: %d | ", tcph->doff * 4);
      printf("標志: ");
      if (tcph->fin) printf("FIN ");
      if (tcph->syn) printf("SYN ");
      if (tcph->rst) printf("RST ");
      if (tcph->psh) printf("PSH ");
      if (tcph->ack) printf("ACK ");
      if (tcph->urg) printf("URG ");
      printf("\n");
      printf("窗體長度: %d | ", ntohs(tcph->window));
      printf("校驗和: 0x%04x | ", ntohs(tcph->check));
      printf("緊急數(shù)據(jù)指針: %d\n", ntohs(tcph->urg_ptr));
    }
  }
  printf("\n");
}

int main(int argc, char* argv[])
{
  pcap_if_t *alldevs;
  pcap_t *adhandle;
  int i = 0;

  EnumAdapters();

  adhandle = BindAdapters(4);

  // 創(chuàng)建套接字
  SOCKET sock = socket(AF_INET, SOCK_RAW, IPPROTO_RAW);
  if (sock == INVALID_SOCKET)
  {
    return -1;
  }

  // 設置套接字屬性
  int one = 1;
  if (setsockopt(sock, IPPROTO_IP, IP_HDRINCL, (char *)&one, sizeof(one)) == SOCKET_ERROR)
  {
    return -1;
  }

  // ---------------------------------------------------------------
  // 構建網(wǎng)絡數(shù)據(jù)包
  // ---------------------------------------------------------------

  char packet[4096];
  memset(packet, 0, 4096);

  struct eth_header *eth = (struct eth_header *)packet;
  struct ip_header *iph = (struct ip_header *)(packet + sizeof(struct eth_header));
  struct tcp_header *tcph = (struct tcp_header *)(packet + sizeof(struct eth_header) + sizeof(struct ip_header));

  // ---------------------------------------------------------------
  // 構建以太網(wǎng)數(shù)據(jù)包頭
  // ---------------------------------------------------------------
  memset(eth->dest, 0xff, 6);  // 目標MAC地址
  memset(eth->src, 0x00, 6);   // 原MAC地址
  eth->type = htons(0x0800);   // IPv4

  // ---------------------------------------------------------------
  // 構建IP數(shù)據(jù)包頭
  // ---------------------------------------------------------------
  iph->ihl = 5;
  iph->version = 4;
  iph->tos = 0;
  iph->tot_len = sizeof(struct ip_header) + sizeof(struct tcp_header);
  iph->id = htons(54321);
  iph->frag_off = 0;
  iph->ttl = 255;
  iph->protocol = IPPROTO_TCP;
  iph->check = 0;
  iph->saddr = inet_addr("192.168.1.1");   // 原始IP地址
  iph->daddr = inet_addr("39.97.203.57");  // 目標IP地址

  // ---------------------------------------------------------------
  // 構建TCP數(shù)據(jù)包頭
  // ---------------------------------------------------------------
  tcph->source = htons(12345);           // 原始TCP端口
  tcph->dest = htons(80);                // 目標TCP端口
  tcph->seq = 0;
  tcph->ack_seq = 0;
  tcph->doff = 5; // TCP 頭部長度
  tcph->fin = 0;
  tcph->syn = 1;
  tcph->rst = 0;
  tcph->psh = 0;
  tcph->ack = 0;
  tcph->urg = 0;
  tcph->window = htons(5840);    // 分配Windows窗體數(shù)
  tcph->check = 0;               // 現(xiàn)在保留校驗和0，稍后用偽標頭填充
  tcph->urg_ptr = 0;

  // ---------------------------------------------------------------
  // 計算校驗和
  // ---------------------------------------------------------------

  // 計算IP校驗和
  iph->check = checksum((unsigned short *)packet, iph->tot_len);

  // TCP 校驗和
  struct
  {
    uint32_t src_addr;
    uint32_t dst_addr;
    uint8_t placeholder;
    uint8_t protocol;
    uint16_t tcp_length;
    struct tcp_header tcp;
  } pseudo_header;

  pseudo_header.src_addr = iph->saddr;
  pseudo_header.dst_addr = iph->daddr;
  pseudo_header.placeholder = 0;
  pseudo_header.protocol = IPPROTO_TCP;
  pseudo_header.tcp_length = htons(sizeof(struct tcp_header));
  memcpy(&pseudo_header.tcp, tcph, sizeof(struct tcp_header));

  tcph->check = checksum((unsigned short *)&pseudo_header, sizeof(pseudo_header));

  // ---------------------------------------------------------------
  // 發(fā)送數(shù)據(jù)包
  // ---------------------------------------------------------------

  struct sockaddr_in dest;
  dest.sin_family = AF_INET;
  dest.sin_addr.s_addr = iph->daddr;

  if (sendto(sock, packet, iph->tot_len, 0, (struct sockaddr *)&dest, sizeof(dest)) == SOCKET_ERROR)
  {
    return -1;
  }

  // ---------------------------------------------------------------
  // 啟用抓包
  // ---------------------------------------------------------------

  pcap_loop(adhandle, 10, packet_handler, NULL);

  pcap_close(adhandle);
  closesocket(sock);
  pcap_freealldevs(alldevs);

  system("pause");
  return 0;
}