- /********************************************************
- * IP报头格式数据结构定义在<netinet/ip.h>中 *
- * ICMP数据结构定义在<netinet/ip_icmp.h>中 *
- * 套接字地址数据结构定义在<netinet/in.h>中 *
- ********************************************************/
- #include <stdio.h>
- #include <stdlib.h>
- #include <signal.h>
- #include <arpa/inet.h>
- #include <sys/types.h>
- #include <sys/socket.h>
- #include <unistd.h>
- #include <netinet/in.h>
- #include <netinet/ip.h>
- #include <netinet/ip_icmp.h>
- #include <netdb.h>
- #include <setjmp.h>
- #include <errno.h>
- #define PACKET_SIZE 4096
- #define MAX_WAIT_TIME 5
- #define MAX_NO_PACKETS 10000
- char *addr[];
- char sendpacket[PACKET_SIZE];
- char recvpacket[PACKET_SIZE];
- int sockfd,datalen = 56;
- int nsend = 0, nreceived = 0;
- double temp_rtt[MAX_NO_PACKETS];
- double all_time = 0;
- double min = 0;
- double max = 0;
- double avg = 0;
- double mdev = 0;
- struct sockaddr_in dest_addr;
- struct sockaddr_in from;
- struct timeval tvrecv;
- pid_t pid;
- void statistics(int sig);
- void send_packet(void);
- void recv_packet(void);
- void computer_rtt(void);
- void tv_sub(struct timeval *out,struct timeval *in);
- int pack(int pack_no);
- int unpack(char *buf,int len);
- unsigned short cal_checksum(unsigned short *addr,int len);
- /*计算rtt最小、大值,平均值,算术平均数差*/
- void computer_rtt()
- {
- double sum_avg = 0;
- int i;
- min = max = temp_rtt[0];
- avg = all_time/nreceived;
- for(i=0; i<nreceived; i++){
- if(temp_rtt[i] < min)
- min = temp_rtt[i];
- else if(temp_rtt[i] > max)
- max = temp_rtt[i];
- if((temp_rtt[i]-avg) < 0)
- sum_avg += avg - temp_rtt[i];
- else
- sum_avg += temp_rtt[i] - avg;
- }
- mdev = sum_avg/nreceived;
- }
- /****统计数据函数****/
- void statistics(int sig)
- {
- computer_rtt(); //计算rtt
- printf("\\n------ %s ping statistics ------\\n",addr[0]);
- printf("%d packets transmitted,%d received,%d%% packet loss,time %.f ms\\n",
- nsend,nreceived,(nsend-nreceived)/nsend*100,all_time);
- printf("rtt min/avg/max/mdev = %.3f/%.3f/%.3f/%.3f ms\\n",
- min,avg,max,mdev);
- close(sockfd);
- exit(1);
- }
- /****检验和算法****/
- unsigned short cal_chksum(unsigned short *addr,int len)
- {
- int nleft = len;
- int sum = 0;
- unsigned short *w = addr;
- unsigned short check_sum = 0;
- while(nleft>1) //ICMP包头以字(2字节)为单位累加
- {
- sum += *w++;
- nleft -= 2;
- }
- if(nleft == 1) //ICMP为奇数字节时,转换最后一个字节,继续累加
- {
- *(unsigned char *)(&check_sum) = *(unsigned char *)w;
- sum += check_sum;
- }
- sum = (sum >> 16) + (sum & 0xFFFF);
- sum += (sum >> 16);
- check_sum = ~sum; //取反得到校验和
- return check_sum;
- }
- /*设置ICMP报头*/
- int pack(int pack_no)
- {
- int i,packsize;
- struct icmp *icmp;
- struct timeval *tval;
- icmp = (struct icmp*)sendpacket;
- icmp->icmp_type = ICMP_ECHO; //ICMP_ECHO类型的类型号为0
- icmp->icmp_code = 0;
- icmp->icmp_cksum = 0;
- icmp->icmp_seq = pack_no; //发送的数据报编号
- icmp->icmp_id = pid;
- packsize = 8 + datalen; //数据报大小为64字节
- tval = (struct timeval *)icmp->icmp_data;
- gettimeofday(tval,NULL); //记录发送时间
- //校验算法
- icmp->icmp_cksum = cal_chksum((unsigned short *)icmp,packsize);
- return packsize;
- }
- /****发送三个ICMP报文****/
- void send_packet()
- {
- int packetsize;
- if(nsend < MAX_NO_PACKETS)
- {
- nsend++;
- packetsize = pack(nsend); //设置ICMP报头
- //发送数据报
- if(sendto(sockfd,sendpacket,packetsize,0,
- (struct sockaddr *)&dest_addr,sizeof(dest_addr)) < 0)
- {
- perror("sendto error");
- }
- }
- }
- /****接受所有ICMP报文****/
- void recv_packet()
- {
- int n,fromlen;
- extern int error;
- fromlen = sizeof(from);
- if(nreceived < nsend)
- {
- //接收数据报
- if((n = recvfrom(sockfd,recvpacket,sizeof(recvpacket),0,
- (struct sockaddr *)&from,&fromlen)) < 0)
- {
- perror("recvfrom error");
- }
- gettimeofday(&tvrecv,NULL); //记录接收时间
- unpack(recvpacket,n); //剥去ICMP报头
- nreceived++;
- }
- }
- /******剥去ICMP报头******/
- int unpack(char *buf,int len)
- {
- int i;
- int iphdrlen; //ip头长度
- struct ip *ip;
- struct icmp *icmp;
- struct timeval *tvsend;
- double rtt;
- ip = (struct ip *)buf;
- iphdrlen = ip->ip_hl << 2; //求IP报文头长度,即IP报头长度乘4
- icmp = (struct icmp *)(buf + iphdrlen); //越过IP头,指向ICMP报头
- len -= iphdrlen; //ICMP报头及数据报的总长度
- if(len < 8) //小于ICMP报头的长度则不合理
- {
- printf("ICMP packet\\'s length is less than 8\\n");
- return -1;
- }
- //确保所接收的是所发的ICMP的回应
- if((icmp->icmp_type == ICMP_ECHOREPLY) && (icmp->icmp_id == pid))
- {
- tvsend = (struct timeval *)icmp->icmp_data;
- tv_sub(&tvrecv,tvsend); //接收和发送的时间差
- //以毫秒为单位计算rtt
- rtt = tvrecv.tv_sec*1000 + tvrecv.tv_usec/1000;
- temp_rtt[nreceived] = rtt;
- all_time += rtt; //总时间
- //显示相关的信息
- printf("%d bytes from %s: icmp_seq=%u ttl=%d time=%.1f ms\\n",
- len,inet_ntoa(from.sin_addr),
- icmp->icmp_seq,ip->ip_ttl,rtt);
- }
- else return -1;
- }
- //两个timeval相减
- void tv_sub(struct timeval *recvtime,struct timeval *sendtime)
- {
- long sec = recvtime->tv_sec - sendtime->tv_sec;
- long usec = recvtime->tv_usec - sendtime->tv_usec;
- if(usec >= 0){
- recvtime->tv_sec = sec;
- recvtime->tv_usec = usec;
- }else{
- recvtime->tv_sec = sec - 1;
- recvtime->tv_usec = -usec;
- }
- }
- /*主函数*/
- main(int argc,char *argv[])
- {
- struct hostent *host;
- struct protoent *protocol;
- unsigned long inaddr = 0;
- // int waittime = MAX_WAIT_TIME;
- int size = 50 * 1024;
- addr[0] = argv[1];
- //参数小于两个
- if(argc < 2)
- {
- printf("usage:%s hostname/IP address\\n",argv[0]);
- exit(1);
- }
- //不是ICMP协议
- if((protocol = getprotobyname("icmp")) == NULL)
- {
- perror("getprotobyname");
- exit(1);
- }
- //生成使用ICMP的原始套接字,只有root才能生成
- if((sockfd = socket(AF_INET,SOCK_RAW,protocol->p_proto)) < 0)
- {
- perror("socket error");
- exit(1);
- }
- //回收root权限,设置当前权限
- setuid(getuid());
- /*扩大套接字的接收缓存区导50K,这样做是为了减小接收缓存区溢出的
- 可能性,若无意中ping一个广播地址或多播地址,将会引来大量的应答*/
- setsockopt(sockfd,SOL_SOCKET,SO_RCVBUF,&size,sizeof(size));
- bzero(&dest_addr,sizeof(dest_addr)); //初始化
- dest_addr.sin_family = AF_INET; //套接字域是AF_INET(网络套接字)
- //判断主机名是否是IP地址
- if(inet_addr(argv[1]) == INADDR_NONE)
- {
- if((host = gethostbyname(argv[1])) == NULL) //是主机名
- {
- perror("gethostbyname error");
- exit(1);
- }
- memcpy((char *)&dest_addr.sin_addr,host->h_addr,host->h_length);
- }
- else{ //是IP 地址
- dest_addr.sin_addr.s_addr = inet_addr(argv[1]);
- }
- pid = getpid();
- printf("PING %s(%s):%d bytes of data.\\n",argv[1],
- inet_ntoa(dest_addr.sin_addr),datalen);
- //当按下ctrl+c时发出中断信号,并开始执行统计函数
- signal(SIGINT,statistics);
- while(nsend < MAX_NO_PACKETS){
- sleep(1); //每隔一秒发送一个ICMP报文
- send_packet(); //发送ICMP报文
- recv_packet(); //接收ICMP报文
- }
- return 0;
- }
- //该片段来自于http://www.codesnippet.cn/detail/05122012817.html
来源: http://www.codesnippet.cn/detail/05122012817.html