原始套接字SOCK_RAW发送UDP数据包

      使用原始套接字发送udp数据包，从传输层封包到链路层（mac头+ip头+udp头）。udp数据包，从传输层封包到链路层（mac头+ip头+udp头）。

head.h文件如下：

 

#ifndef _HEAD_H
#define _HEAD_H    

#define BUFFER_MAX 2048
#define PCKT_LEN 8492

#pragma pack (1)
//ethernet head 14 bytes
struct ether
{
	char dmac[6];
	char smac[6];
	char eth_typ_len[2];
};


//ip head 20 bytes
struct ipheader {

 unsigned char      iplv;//iph_ihl:5, iph_ver:4;

 unsigned char      iph_tos;

 unsigned short int iph_len;

 unsigned short int iph_ident;

// unsigned uint8_t      iph_flag;

 unsigned short int iph_offset;//16bit include flag and offset

 unsigned char      iph_ttl;

 unsigned char      iph_protocol;

 unsigned short int iph_chksum;

 unsigned int       iph_sourceip;

 unsigned int       iph_destip;

};

//udp head 8 bytes
struct udpheader {

 unsigned short int udph_srcport;

 unsigned short int udph_destport;

 unsigned short int udph_len;

 unsigned short int udph_chksum;

};

//tcp head 20bytes
struct tcphdr
{
    unsigned short int source;  
    unsigned short int dest;   
    unsigned int seq;  
    unsigned int ack_seq; 
    unsigned short int tcp_len;
#if 0
    unsigned short int doff:4;
    unsigned short int res1:4;
    unsigned short int res2:2;
    unsigned short int urg:1;
    unsigned short int ack:1;
    unsigned short int psh:1;
    unsigned short int rst:1;
    unsigned short int syn:1;
    unsigned short int fin:1;
#endif
    unsigned short int window;  
    unsigned short int check;  
    unsigned short int urg_prt;  
};

#pragma pack ()

#endif

 

 

 

 

 

raw_udp.c文件如下：

 

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