sniffer.cpp

创新实验snifer代码

#include <winsock2.h>
#include <windows.h>
#include <ws2tcpip.h>
#include <stdio.h>
#include <stdlib.h>

#define MAX_HOSTNAME_LAN 255
#define SIO_RCVALL _WSAIOW(IOC_VENDOR,1)
#define MAX_ADDR_LEN 16






typedef struct tcpheader {
     unsigned short int sport;//16位源端口 
     unsigned short int 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_x2:4;
     unsigned char th_off:4;
     unsigned char Flags;//6位标志位
     unsigned short int th_win;//16位窗口大小
     unsigned short int th_sum;//16位校验和
     unsigned short int th_urp;//16位紧急数据偏移量
}TCP_HDR;



struct ipheader {
unsigned char ip_hl:4, ip_v:4; //4位首部长度+4位IP版本号
unsigned char ip_tos;//8位服务类型TOS
unsigned short int ip_len; //16位总长度（字节）
unsigned short int ip_id;//16位标识
unsigned short int ip_off;
unsigned char ip_ttl;//8位生存时间 TTL
unsigned char ip_p;
unsigned short int ip_sum;
unsigned int ip_src;//32位源IP地址
unsigned int ip_dst;//32位目的IP地址 
}; /* total ip header length: 20 bytes (=160 bits) */

// Psuedo Header

typedef struct ps_hdr
{
    unsigned int   source_address;   // Source Address         =>      4 Bytes
    unsigned int   dest_address;     // Destination Address     =>      4 Bytes
    unsigned char  placeholder;         // Place Holder         =>      1 Bytes
    unsigned char  protocol;         // Protocol         =>      1 Bytes
    unsigned short tcp_length;         // TCP Length         =>    +  2 Bytes
                     //                       = 12 Bytes
    struct tcpheader tcp;

}PS_HDR;

typedef struct udphdr {
unsigned short sport;
unsigned short dport;
unsigned short len;
unsigned short cksum;
}UDP_HDR;

//十六进制输出
void hexdump(char *pointer)
{
    if ((*(pointer)>0))
    printf("\\x%2.2i",*(pointer));
    else
//pointer指向的字节超过Ascii码的范围，进行转换
    printf("\\x%2.2i",(*(pointer))*(-1)+82);
}

void main()
{
    SOCKET sock;
    WSADATA wsd;
    char RecvBuf[65535] = {0};
    DWORD  dwBytesRet;
    int pCount=0;
    unsigned int  optval = 1; //the pointer , which shows us the payload begin
    unsigned char *datatcp=NULL; //the pointer , which shows us the payload begin
    unsigned char *dataudp=NULL;
    int lentcp=0, lenudp;

    WSAStartup(MAKEWORD(2,1),&wsd);
	//创建套接字
    if((sock = socket(AF_INET, SOCK_RAW, IPPROTO_IP))==SOCKET_ERROR)
    {
        exit(1);
    }

    char FAR name[MAX_HOSTNAME_LAN];
    gethostname(name, MAX_HOSTNAME_LAN);
	//获取本机相关信息
    struct hostent FAR * pHostent;
    pHostent = (struct hostent * )malloc(sizeof(struct hostent));
    pHostent = gethostbyname(name);

    SOCKADDR_IN sa;
    sa.sin_family = AF_INET;
    sa.sin_port = htons(6000);

    memcpy(&sa.sin_addr.S_un.S_addr, pHostent->h_addr_list[0], pHostent->h_length);

    bind(sock, (SOCKADDR *)&sa, sizeof(sa));
    //if you don't have raw socket support (win 95/98/me/win2kuser) it calls the exit(1) function
    if ((WSAGetLastError())==10013)
    exit(1);
	//改变socket属性
    WSAIoctl(sock, SIO_RCVALL, &optval, sizeof(optval), NULL, 0, &dwBytesRet, NULL, NULL);

    struct udphdr *pUdpheader;
    struct ipheader *pIpheader;
    struct tcpheader *pTcpheader;
    char szSourceIP[MAX_ADDR_LEN], szDestIP[MAX_ADDR_LEN];
    SOCKADDR_IN saSource, saDest;
    pIpheader = (struct ipheader *)RecvBuf;
    pTcpheader = (struct tcpheader *)(RecvBuf+ sizeof(struct ipheader ));
    pUdpheader = (struct udphdr *) (RecvBuf+ sizeof(struct ipheader ));

    while (1)
    {
        
        memset(RecvBuf, 0, sizeof(RecvBuf));
        recv(sock, RecvBuf, sizeof(RecvBuf), 0);
        saSource.sin_addr.s_addr = pIpheader->ip_src;
        strncpy(szSourceIP, inet_ntoa(saSource.sin_addr), MAX_ADDR_LEN);
        //Check Dest IP
        saDest.sin_addr.s_addr = pIpheader->ip_dst;
        strncpy(szDestIP, inet_ntoa(saDest.sin_addr), MAX_ADDR_LEN);
        
        lentcp =(ntohs(pIpheader->ip_len)-(sizeof(struct ipheader)+sizeof(struct tcpheader)));    
        lenudp =(ntohs(pIpheader->ip_len)-(sizeof(struct ipheader)+sizeof(struct udphdr)));        

        if(    (pIpheader->ip_p)==IPPROTO_TCP&&lentcp!=0)
        {

            printf("*******************************************\n");
            pCount++;    
            datatcp=(unsigned char *) RecvBuf+sizeof(struct ipheader)+sizeof(struct tcpheader);
            printf("-TCP-\n");                    
            printf("\nDestination address->%s\n",szDestIP);
            printf("\nDestination port->%i\n",ntohs(pTcpheader->dport));
            printf("datatcp address->%x\n",datatcp);
            printf("size of ipheader->%i\n",sizeof(struct ipheader));
            printf("size of tcpheader->%i\n",sizeof(struct tcpheader));
            printf("size of the hole packet->%i\n",ntohs(pIpheader->ip_len));
            printf("\nchar Packet%i []=\"",pCount,lentcp);
            for (int i=0;i<lentcp;i++)
            {
                printf("\\x%.2x",*(datatcp+i)); //hexdump(datatcp+i);
                if(i%10==0)
                {                        
                    printf("\"");
                    printf("\n\"");
                }

            }
            printf("\";\n\n\n");
            for (int i2=0;i2<lentcp;i2++)
            {
				//接受的数据是可打印字符
                if( *(datatcp+i2)<=127&&*(datatcp+i2)>=20)
                    printf("%c",*(datatcp+i2));
                else
                    printf(".");
            }
            printf("\n\n");
            printf("*******************************************\n");    
        }

        if(    (pIpheader->ip_p)==IPPROTO_UDP&&lentcp!=0)
        {
            pCount++;                        
            dataudp=(unsigned char *) RecvBuf+sizeof(struct ipheader)+sizeof(struct udphdr);
            printf("-UDP-\n");
            printf("\nDestination address->%s\n",szDestIP);
            printf("\nDestination port->%d\n",ntohs(pTcpheader->dport));
            printf("dataudp address->%x\n",dataudp);
            printf("size of ipheader->%i\n",sizeof(struct ipheader));
            printf("size of udpheader->%i\n",sizeof(struct udphdr));
            printf("size of the hole packet->%i\n",ntohs(pIpheader->ip_len));
            printf("\nchar Packet%i []=\"",pCount,lenudp);
            for (int x=0;x<lenudp;x++)
            {
                printf("\\x%.2x",*(dataudp+x));
                if (x%10==0) 
                {                        
                    printf("\"");
                    printf("\n\"");
                }
            }
            printf("\";\n\n\n");
            for (int x2=0;x2<lenudp;x2++)
            {
                if( *(dataudp+x2)<=127&&*(dataudp+x2)>=20)
                    printf("%c",*(dataudp+x2));
                else
                    printf(".");
            }
            printf("\n\n");
            printf("*******************************************\n");
        }
    } 
}