計網實驗c/c++、網路嗅探器的設計與實作

參照附錄 4 raw socket 編程例子，設計一個可以監視網路的狀態、資料流動情況以及網路上傳輸 的資訊的網路嗅探器，
顯示了流量資訊，若要查看報文資訊請修改注釋，
自動獲取ip

#include <iostream>
#include <winsock2.h>
#include <time.h>
#pragma comment(lib, "WS2_32")
using namespace std;

void DecodeIPPacket(char *pData);

void DecodeTCPPacket(char *pData);

void DecodeUDPPacket(char *pData);

void DecodeICMPPacket(char *pData);

#define SIO_RCVALL            _WSAIOW(IOC_VENDOR,1)
double all=0;
/*****IP分組首部結構******/
//IP首部結構
typedef struct _IPHeader {
    unsigned char iphVerLen; // 版本號和頭長度各占4位
    unsigned char ipTOS;  // 服務型別
    unsigned short ipLength; // 分組總長度
    unsigned short ipID; //分組標識，惟一標識發送的每一個資料報
    unsigned short ipFlags; // 標志
    unsigned char ipTTL; // 生存時間，TTL
    unsigned char ipProtocol; // 協議可以是TCP、UDP、ICMP等
    unsigned short ipChecksum; // 校驗和
    unsigned long ipSource; // 源IP地址
    unsigned long ipDestination; // 目的IP地址
} IPHeader, *PIPHeader;

//ICMP報頭結構******/
typedef struct icmphdr {
    char i_type;  //8 位型別欄位
    char i_code;  //8 位代碼欄位
    unsigned short i_cksum;  //16位校驗和
    unsigned short i_id;    //識別符號，一般可設為發送行程的ID
    unsigned short i_seq;   //序列號
    unsigned long timestamp;  //時間戳
} ICMPHeader;

//UDP報頭結構
typedef struct _UDPHeader {
    unsigned short sourcePort;    // 源埠號
    unsigned short destinationPort; // 目的埠號
    unsigned short len;          // 包長度
    unsigned short checksum;    // 校驗和
} UDPHeader;

//TCP報頭結構
typedef struct _TCPHeader {
    unsigned short sourcePort;        // 16位源埠號
    unsigned short destinationPort;    // 16位目的埠號
    unsigned long sequenceNumber;    // 32位序列號
    unsigned long acknowledgeNumber;    // 32位確認號
    char dataoffset;    //高4位表示資料偏移
    char flags;    //低6位為URG、ACK、PSH、RST、SYNhe FIN六個標志位
    unsigned short windows;        // 16位視窗大小
    unsigned short checksum;        // 16位校驗和
    unsigned short urgentPointer;        // 16位緊急資料偏移量
} TCPHeader;

int main() {
    setvbuf(stdout, NULL, _IONBF, 0);
    WSADATA wsaData;                              // 用來存盤被WSAStartup函式呼叫后回傳的Windows Sockets資料
    WSAStartup(MAKEWORD(2, 2), &wsaData);     // 完成對Winsock服務的初始化
    /**** 創建原始套節字 IPv4 TCP******/
    SOCKET sRaw = socket(PF_INET, SOCK_RAW, 0);
    SOCKADDR_IN addr_in;                            // 目的地址
    /*****輸入想要要監聽的介面的IP地址******/
    //cout << "請輸入要監聽介面的IP地址:";
    char snfIP[20];
    //cin.getline(snfIP, sizeof(snfIP));
    char hostname[256];
    gethostname(hostname,sizeof(hostname));   //獲取主機資訊
    HOSTENT* host=gethostbyname(hostname);
    strcpy(snfIP,inet_ntoa(*(in_addr*)*host->h_addr_list));     //copy主機資訊中的ip到snfIP
    addr_in.sin_family = AF_INET;                       // IPv4
    addr_in.sin_port = htons(80);            // 80埠
    addr_in.sin_addr.S_un.S_addr = inet_addr(snfIP);    // 監聽的地址

    /****系結網卡IP地址******/
    bind(sRaw, (PSOCKADDR) &addr_in, sizeof(addr_in));

    /****在呼叫ioctlsocket將網卡設為混雜模式前，套節字必須系結該網卡的IP地址******/
    DWORD dwValue = 1;
    // 套接字 SIO_RCVALL操作為所有的IP包無論經不經過
    ioctlsocket(sRaw, SIO_RCVALL, &dwValue);
    // 開始抓取IP分組
    char buff[50][4096];
    int packetNumber;
    int time=0;
    while (1) {
        long t=clock();
        double v=0.0;
        recv(sRaw, buff[0], 4096, 0);
        //cout << endl;
        DecodeIPPacket(buff[0]);//決議IP包
        //cout <<clock()-t<< endl;
        time+=clock()-t;
        if(time>1000){
            v=all/1024;
            //cout <<all<<"Bytes/s"<< endl;
            printf("%.02fKB/s\n",v);
            all=0;
            time=0;
        }
        //v=(all-a)/((clock()-t)*1000);
        //cout <<v <<"bytes/s"<< endl;
    }
    closesocket(sRaw);
    WSACleanup();
    return 0;
}
/**********IP分組決議函式*************/
void DecodeIPPacket(char *pData) {
    int n = 0;
    IPHeader *pIPHdr = (IPHeader *) pData;
    // 源地址和目的地址
    in_addr source, dest;
    char szSourceIp[32], szDestIp[32];
    /***從IP頭中取出源IP地址和目的IP地址***/
    source.S_un.S_addr = pIPHdr->ipSource;          // 設定源地址
    dest.S_un.S_addr = pIPHdr->ipDestination;       // 設定目的地址
    strcpy(szSourceIp, inet_ntoa(source));
    strcpy(szDestIp, inet_ntoa(dest));
   /* cout << "源IP:" << szSourceIp;
    cout << "目的IP: " << szDestIp << endl;*/
    int nHeaderLen = (pIPHdr->iphVerLen & 0xf) * sizeof(ULONG);// IP頭長度
   // cout << "大小：" << ntohs(pIPHdr->ipLength) << endl;
    all+=ntohs(pIPHdr->ipLength);
    switch (pIPHdr->ipProtocol) // 協議
    {
        case IPPROTO_TCP: // 呼叫函式決議TCP包
            DecodeTCPPacket(pData + nHeaderLen);
            break;
        case IPPROTO_UDP:// 呼叫函式決議UDP包
            DecodeUDPPacket(pData + nHeaderLen);
            break;
        case IPPROTO_ICMP:// 呼叫函式決議ICMP包
            DecodeICMPPacket(pData + nHeaderLen);
            break;
        default:
            cout << " 協議號:" << (int) pIPHdr->ipProtocol << endl;
    }
}

/*********TCP包決議函式***********/
void DecodeTCPPacket(char *pData) {
    TCPHeader *pTCPHdr = (TCPHeader *) pData;
    /*cout << "TCP Source Port: " << ntohs(pTCPHdr->sourcePort);
    cout << "  Destination Port: " << ntohs(pTCPHdr->destinationPort) << endl;
    cout << pTCPHdr ->windows<<endl;*/

}

/***********UDP包決議函式**********/
void DecodeUDPPacket(char *pData) {
    UDPHeader *pUDPHdr = (UDPHeader *) pData;
   /* cout << "UDP Source Port: " << ntohs(pUDPHdr->sourcePort);
    cout << "  Destination Port: " << ntohs(pUDPHdr->destinationPort) << endl;*/
    //cout << ntohs(pUDPHdr ->len)<<endl;
}

/***********ICMP包決議函式 **********/
void DecodeICMPPacket(char *pData) {
    ICMPHeader *pICMPHdr = (ICMPHeader *) pData;
    cout << "ICMP Type: " << pICMPHdr->i_type << "Code: " << pICMPHdr->i_code << endl;

    switch (pICMPHdr->i_type) {
        case 0:
            cout << "Echo Response.\n";
            break;
        case 8:
            cout << "Echo Request.\n";
            break;
        case 3:
            cout << "Destination Unreachable.\n";
            break;
        case 11:
            cout << "Datagram Timeout（TTL＝0).\n";
            break;
    }
}


``