ping.cpp

用c++编的 值得大家借鉴 老师给的一个例子 看看吧有用就下了

/******************************************************************************\ 
|       命令行输入格式为：目标IP地址(主机名) 数据包个数 数据包大小             |                      
|          如：127.0.0.1 10 100  或：								     	   |
|             computer 10 100                                                  |
\******************************************************************************/ 

//#pragma pack(4) //使用伪指令#pragma pack (n)，编译器将按照n个字节对齐

#include <stdio.h>
#include <winsock2.h>
//#include <ws2tcpip.h>

#define ICMP_ECHO 8 //回显请求
#define ICMP_ECHOREPLY 0 

#define ICMP_MIN 8 // ICMP的头部长度最小为8B 

/* The IP header */ 
typedef struct iphdr { 
	unsigned int h_len:4; // length of the header   16Bytes
	unsigned int version:4; // Version of IP 
	unsigned char tos; // Type of service 
	unsigned short total_len; // total length of the packet 
	unsigned short ident; // unique identifier 
	unsigned short frag_and_flags; // flags 
	unsigned char ttl; 
	unsigned char proto; // protocol (TCP, UDP etc) 
	unsigned short checksum; // IP checksum 
	
	unsigned int sourceIP; 
	unsigned int destIP; 
	
}IpHeader; 

// 
// ICMP header 
// 
typedef struct icmphdr { 
	BYTE i_type; 
	BYTE i_code; /* type sub code */ 
	USHORT i_cksum; 
	USHORT i_id; //标识
	USHORT i_seq; //序列号
	/* This is not the std header, but we reserve space for time */ 
	ULONG timestamp; 
}IcmpHeader; 

#define STATUS_FAILED 0xFFFF 
#define DEF_PACKET_SIZE    32
#define DEF_PACKET_NUMBER  4    /* 默认发送数据报的个数 */
#define MAX_PACKET 1024 

#define xmalloc(s) HeapAlloc(GetProcessHeap(),HEAP_ZERO_MEMORY,(s)) //用HeapAlloc（）函数来分配内存
#define xfree(p) HeapFree (GetProcessHeap(),0,(p)) //用HeapAlloc（）函数来释放内存

void fill_icmp_data(char *, int); 
USHORT checksum(USHORT *, int); 
int decode_resp(char *,int ,struct sockaddr_in *); 

void Usage(){ //提示信息
	
	fprintf(stderr,"Usage:\n"); 
	fprintf(stderr,"[destIP] [number of packets] [data_size]\n"); 
	fprintf(stderr,"datasize can be up to 1Kb\n"); 
	ExitProcess(STATUS_FAILED); 
	
} 
int main(int argc, char *argv[])
{ 
	
	WSADATA wsaData; 
	SOCKET sockRaw; 
	struct sockaddr_in dest,from; 
	struct hostent * hp; 
	int bread,datasize,times; 
	int fromlen = sizeof(from); 
	int timeout = 1000;
	int statistic = 0;  /* 用于统计结果 */  
	char *dest_ip; 
	char *icmp_data; 
	char *recvbuf; 
	unsigned int addr=0; 
	USHORT seq_no = 0; 
	
	if (WSAStartup(MAKEWORD(2,1),&wsaData) != 0){ 
		fprintf(stderr,"WSAStartup failed: %d\n",GetLastError()); 
		ExitProcess(STATUS_FAILED); 
	} 
	
	if (argc <2 ) { 
		Usage(); //没输入命令参数时，调用Usage提示用户输入。
	} 
	sockRaw = WSASocket(AF_INET,SOCK_RAW,IPPROTO_ICMP,NULL, 0,WSA_FLAG_OVERLAPPED);
	
	//
	//注：为了使用发送接收超时设置(即设置SO_RCVTIMEO, SO_SNDTIMEO)，
	//    必须将标志位设为WSA_FLAG_OVERLAPPED !
	// 
	
	if (sockRaw == INVALID_SOCKET) { 
		fprintf(stderr,"WSASocket() failed: %d\n",WSAGetLastError()); 
		ExitProcess(STATUS_FAILED); 
	} 
	bread = setsockopt(sockRaw,SOL_SOCKET,SO_RCVTIMEO,(char*)&timeout, 
		sizeof(timeout)); //设置接收超时
	if(bread == SOCKET_ERROR) { 
		fprintf(stderr,"failed to set recv timeout: %d\n",WSAGetLastError()); 
		ExitProcess(STATUS_FAILED); 
	} 
	timeout = 1000; 
	bread = setsockopt(sockRaw,SOL_SOCKET,SO_SNDTIMEO,(char*)&timeout, 
		sizeof(timeout)); //设置发送超时
	if(bread == SOCKET_ERROR) { 
		fprintf(stderr,"failed to set send timeout: %d\n",WSAGetLastError()); 
		ExitProcess(STATUS_FAILED); 
	} 
	memset(&dest,0,sizeof(dest)); 
	
	hp = gethostbyname(argv[1]); //如果解析失败，返回NULL
	//从用户的命令行参数获取目标IP地址
	if (!hp){ 
		addr = inet_addr(argv[1]); 
	} 
	if ((!hp) && (addr == INADDR_NONE) ) { 
		fprintf(stderr,"命令行格式错误，无法解析%s!\n",argv[1]); 
		ExitProcess(STATUS_FAILED); 
	} 
	
	if (hp != NULL) 
		memcpy(&(dest.sin_addr),hp->h_addr,hp->h_length); 
	else 
		dest.sin_addr.s_addr = addr; 
	
	if (hp) 
		dest.sin_family = hp->h_addrtype; 
	else 
		dest.sin_family = AF_INET; 
	
	dest_ip = inet_ntoa(dest.sin_addr); 
	
	// 
	//  atoi函数原型是: int atoi( const char *string );
	//  The return value is 0 if the input cannot be converted to an integer !
	//
	if(argc>2)
	{
		times=atoi(argv[2]);//从参数中获取数据包个数
		if(times == 0)//如果用户设定为0，则采用默认的4个
			times=DEF_PACKET_NUMBER;
	}
	else
		times=DEF_PACKET_NUMBER;
	
	if (argc >3) 
	{ 
		datasize = atoi(argv[3]); //从参数中获取每个数据包的大小
		if (datasize == 0) 
			datasize = DEF_PACKET_SIZE;
		if (datasize >1024)   /* 用户给出的数据包大小太大 */
		{
			fprintf(stderr,"WARNING : data_size is too large !\n");
			datasize = DEF_PACKET_SIZE; //如果超出规定的大小，则采用默认的大小
		}
	} 
	else 
		datasize = DEF_PACKET_SIZE; 
	
	datasize += sizeof(IcmpHeader); //sizeof(IcmpHeader)=12B
	
	icmp_data = (char*)xmalloc(MAX_PACKET); 
	recvbuf = (char*)xmalloc(MAX_PACKET); //MAX_PACKET=1024
	
	if (!icmp_data) { 
		fprintf(stderr,"HeapAlloc failed %d\n",GetLastError()); 
		ExitProcess(STATUS_FAILED); 
	} 
	
	
	memset(icmp_data,0,MAX_PACKET); //将ICMP的数据字段请0
	fill_icmp_data(icmp_data,datasize); //datasize是ICMP数据长度和头部长度的总和
	
	//
	//显示提示信息
	//
	fprintf(stdout,"\nPinging %s ....\n\n",dest_ip);
	
	
	for(int i=0;i<times;i++){ 
		int bwrote; 
		
		((IcmpHeader*)icmp_data)->i_cksum = 0; //先将校验和字段设置为0
		((IcmpHeader*)icmp_data)->timestamp = GetTickCount(); 
		//GetTickCount返回从操作系统启动到现在所经过的毫秒数
		((IcmpHeader*)icmp_data)->i_seq = seq_no++; 
		((IcmpHeader*)icmp_data)->i_cksum = checksum((USHORT*)icmp_data,datasize);
		
		bwrote = sendto(sockRaw,icmp_data,datasize,0,(struct sockaddr*)&dest,sizeof(dest)); 
		if (bwrote == SOCKET_ERROR){ 
			if (WSAGetLastError() == WSAETIMEDOUT) { 
				printf("Request timed out.\n"); 
				continue; 
			} 
			fprintf(stderr,"sendto failed: %d\n",WSAGetLastError()); 
			ExitProcess(STATUS_FAILED); 
		} 
		if (bwrote < datasize ) { 
			fprintf(stdout,"Wrote %d bytes\n",bwrote); 
		} 
		bread = recvfrom(sockRaw,recvbuf,MAX_PACKET,0,(struct sockaddr*)&from,&fromlen); 
		if (bread == SOCKET_ERROR){ 
			if (WSAGetLastError() == WSAETIMEDOUT) { 
				printf("Request timed out.\n"); 
				continue; 
			} 
			fprintf(stderr,"recvfrom failed: %d\n",WSAGetLastError()); 
			ExitProcess(STATUS_FAILED); 
		} 
		if(!decode_resp(recvbuf,bread,&from))
			statistic++; /* 成功接收的数目++ */
		Sleep(1000); 
		
	}
	
	/*
	Display the statistic result
	*/
	fprintf(stdout,"\nPing statistics for %s \n",dest_ip);
	fprintf(stdout,"    Packets: Sent = %d,Received = %d, Lost = %d (%2.0f%% loss)\n",times,
		statistic,(times-statistic),(float)(times-statistic)/times*100);
	
	
	WSACleanup();
	return 0; 
	
} 
/* 
接收到的应答数据包是IP数据包，所以必须从中分离出ICMP数据包
*/ 
int decode_resp(char *buf, int bytes,struct sockaddr_in *from) { 
	
	IpHeader *iphdr; 
	IcmpHeader *icmphdr; 
	unsigned short iphdrlen; 
	
	iphdr = (IpHeader *)buf; 
	
	iphdrlen = (iphdr->h_len) * 4 ; // number of 32-bit words *4 = bytes 
	
	if (bytes < iphdrlen + ICMP_MIN) { 
		printf("Too few bytes from %s\n",inet_ntoa(from->sin_addr)); 
	} 
	
	icmphdr = (IcmpHeader*)(buf + iphdrlen); 
	
	if (icmphdr->i_type != ICMP_ECHOREPLY) //如果不是回显应答报文
	{ 
		fprintf(stderr,"non-echo type %d recvd\n",icmphdr->i_type); 
		return 1; 
	} 
	if (icmphdr->i_id != (USHORT)GetCurrentProcessId()) { 
		fprintf(stderr,"someone else's packet!\n"); 
		return 1; 
	} 
	printf("%d bytes from %s:",bytes-sizeof(IcmpHeader)-iphdrlen, inet_ntoa(from->sin_addr)); 
	printf(" icmp_seq = %d. ",icmphdr->i_seq); 
    if(GetTickCount()-icmphdr->timestamp<1) //计算依次往返的时间,ms为单位
	printf("time<1ms");
	else 
	printf("time: %d ms ",GetTickCount()-icmphdr->timestamp); 
	printf("\n");
	return 0; 
	
} 


USHORT checksum(USHORT *buffer, int size) //USHORT是16位
{ 
	
	unsigned long cksum=0; 
	
	while(size >1) 
	{ 
		cksum+=*buffer++; 
		size -=sizeof(USHORT); 
	} 
	
	if(size) { 
		cksum += *(UCHAR*)buffer; 
	} 
	
	cksum = (cksum >> 16) + (cksum & 0xffff); 
	cksum += (cksum >>16); 
	return (USHORT)(~cksum); 
} 
/* 
Helper function to fill in various stuff in our ICMP request. 
*/ 
void fill_icmp_data(char * icmp_data, int datasize){ 
	
	IcmpHeader *icmp_hdr; 
	char *datapart; 
	
	icmp_hdr = (IcmpHeader*)icmp_data; 
	
	icmp_hdr->i_type = ICMP_ECHO; //ICMP数据包数据回显请求类型
	icmp_hdr->i_code = 0; //回显请求的代码字段必须设为0
	icmp_hdr->i_id = (USHORT)GetCurrentProcessId(); 
	icmp_hdr->i_cksum = 0; 
	icmp_hdr->i_seq = 0; 
	
	datapart = icmp_data + sizeof(IcmpHeader); //将指向ICMP头部的指加上偏移量指向可选数据部分
	
	// 
	// 可选数据字段可以填充任何数据
	// datasize - sizeof(IcmpHeader)是用户命令行参数里设定的数据长度
	memset(datapart,'E', datasize - sizeof(IcmpHeader)); 
	
}