vc++实现网路嗅探    

#include

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

#define SIO_RCVALL _WSAIOW(IOC_VENDOR,1)

struct IPHEAD
{
    unsigned char h_len:4;//4位首部长度+4位IP版本号
    unsigned char ver:4;
    unsigned char tos;//8位服务类型TOS
    unsigned short total_len;//16位总长度（字节）
    unsigned short ident;//16位标识
    unsigned short frag_and_flags;//3位标志位
    unsigned char ttl;//8位生存时间 TTL
    unsigned char proto;//8位协议 (TCP, UDP 或其他)
    unsigned short checksum;//16位IP首部校验和
    unsigned int sourceip;//32位源IP地址
    unsigned int destip;//32位目的IP地址
};

struct TCPHEAD //定义TCP首部
{
USHORT th_sport; //16位源端口
USHORT th_dport; //16位目的端口
unsigned int th_seq; //32位序列号
unsigned int th_ack; //32位确认号
unsigned char th_lenres; //4位首部长度/6位保留字
unsigned char th_flag; //6位标志位
USHORT th_win; //16位窗口大小
USHORT th_sum; //16位校验和
USHORT th_urp; //16位紧急数据偏移量
};

char *phostlist[10];//列举主机网卡的数组

DWORD _stdcall listen(void *p)
{
    SOCKET s;
    struct sockaddr_in addr;
    int itimeout=1000;
    int ret;
    char cbuf[1500];//接收数据缓冲区
    struct IPHEAD *piphd;//定义IP头结构
 struct TCPHEAD *ptcphd;//定义TCP头结构
 
    s=socket(AF_INET,SOCK_RAW,IPPROTO_RAW); //创建一个原始套接字
    setsockopt(s,SOL_SOCKET,SO_RCVTIMEO,(char*)&itimeout,sizeof(itimeout));

    memset(&addr,0,sizeof(addr));
    addr.sin_family=AF_INET;
    addr.sin_addr.S_un.S_addr=inet_addr((char *)p);
    addr.sin_port=htons(6000);//设置本地端口号
    bind(s,(struct sockaddr *)&addr,sizeof(addr));//绑定端口
    //设置sock_raw为sio_rcvall,以便接收所有IP包
    DWORD dwin=1;
    DWORD dwout[10];
    DWORD dwret;
    WSAIoctl(s,SIO_RCVALL,&dwin,sizeof(dwin),&dwout,sizeof(dwout),&dwret,NULL,NULL);

    for(;;)
    {
        ret=recv(s,cbuf,sizeof(cbuf),0);//接收数据
        if(ret==SOCKET_ERROR)
        {
            if(WSAGetLastError()==WSAETIMEDOUT)continue;
            closesocket(s);
            return 0;
        }

        piphd=(struct IPHEAD *)cbuf;//取得IP头数据的地址
  int iIphLen = sizeof(unsigned long) * (piphd->h_len  & 0xf);
  ptcphd=(struct TCPHEAD *)(cbuf+iIphLen);//取得TCP头数据的地址

        printf("From : %s /t port %d/t",inet_ntoa(*(struct in_addr*)&piphd->sourceip),ntohs(ptcphd->th_sport) );
        printf("To : %s /t port %d  ",inet_ntoa(*(struct in_addr*)&piphd->destip),ntohs(ptcphd->th_dport));
 
        switch(piphd->proto)//根据IP头的协议判断数据包协议类型
        {
        case 1:
            printf("ICMP/n");
            break;
        case 2:
            printf("IGMP/n");
            break;
        case 6:
            printf("TCP/n");
            break;
        case 17:
            printf("UDP/n");
            break;
        default:
            printf("unknow:%d/n",piphd->proto);
        }
    }

    return 1;
}

void main()
{
 //初始化sock
    WSADATA wsa;
    int i=0;
    DWORD dwtid;
    char chname[128];
    hostent *host;

    WSAStartup(MAKEWORD(2,1),&wsa);
 gethostname(chname,sizeof(chname));
    host=gethostbyname(chname);
    while(host->h_addr_list[i]!=NULL)//取所有网卡序号，为每个网卡开启一个监听线程
    {
        phostlist[i]=(char *)malloc(16);
        sprintf(phostlist[i],"%s",inet_ntoa(*(struct in_addr *)host->h_addr_list[i]));
        printf("Bind to %s/n",phostlist[i]);
        CreateThread(NULL,0,listen,phostlist[i],0,&dwtid);
        i++;
    }

    for(;;)//为每个网卡创建监听线程后要用一个循环防止主线程退出
    {
        Sleep(10);
    }
}