www.pudn.com > udp.rar > udpClient.cpp

#include  
#include "Winsock2.h" 
#include 
#include 
#include 
#include  
#pragma comment(lib,"ws2_32.Lib") 
#define SEND_SIZE 32  
#define PACKET_SIZE 4096 
#define ICMP_ECHO 8 
#define ICMP_ECHOREPLY 0 
struct icmp 
{ 
	unsigned char icmp_type; 
	unsigned char icmp_code; 
	unsigned short icmp_cksum; 
	unsigned short icmp_id; 
	unsigned short icmp_seq; 
	unsigned long icmp_data;  
}; 
 
struct ip 
{ 
	unsigned char ip_hl:4;       
	unsigned char ip_v:4;        
	unsigned char ip_tos;           
	unsigned short ip_len;         
	unsigned short ip_id;          
	unsigned short ip_off;         
	unsigned char ip_ttl;           
	unsigned char ip_p;          
	unsigned short ip_sum;         
	unsigned long ip_src; 
	unsigned long ip_dst;  
}; 
unsigned char sendpacket[PACKET_SIZE]; 
unsigned char recvpacket[PACKET_SIZE]; 
struct sockaddr_in dest_addr; 
struct sockaddr_in from_addr; 
int sockfd; 
int pid; 
 
unsigned short cal_chksum(unsigned short *addr,int len); 
int pack(int pack_no); 
int unpack(unsigned char *buf,int len); 
void send_packet(void); 
void recv_packet(void); 
void main() 
{ 
	printf("Connect To Server Please Wait.....\n"); 
	WORD wVersionRequested; 
	WSADATA wsaData; 
	int err; 
	struct hostent *host; 
	struct protoent *protocol; 
	 
	int timeout=1000; 
	int SEND_COUNT=1; 
	int i; 
	char *par_host = "www.soft100.net"; 
	wVersionRequested = MAKEWORD( 1, 1 ); 
 
	err = WSAStartup( wVersionRequested, &wsaData ); 
	if ( err != 0 ) { 
		return; 
	} 
 
	                             
 
	if ( LOBYTE( wsaData.wVersion ) != 1 || 
		HIBYTE( wsaData.wVersion ) != 1) { 
			 
			WSACleanup( ); 
			return;  
		} 
		/*if(WSAStartup(0x1010,&wsaData)!=0) 
		{ 
			printf("wsastartup error\n"); 
			exit(1); 
		}*/  
		if( (protocol=getprotobyname("icmp") )==NULL) 
		{ 
			printf("getprotobyname error\n"); 
			exit(1); 
		} 
		if( (sockfd=socket(AF_INET,SOCK_RAW,protocol->p_proto) )<0) 
		{   
			printf("socket error\n"); 
			exit(1); 
		} 
		if(setsockopt(sockfd,SOL_SOCKET,SO_RCVTIMEO,(char*)&timeout,sizeof(timeout))<0)  
			fprintf(stderr,"failed to set recv timeout: %d\n",WSAGetLastError()); 
		if(setsockopt(sockfd,SOL_SOCKET,SO_SNDTIMEO,(char*)&timeout,sizeof(timeout))<0) 
			fprintf(stderr,"failed to set send timeout: %d\n",WSAGetLastError());       
 
		memset(&dest_addr,0,sizeof(dest_addr)); 
		dest_addr.sin_family=AF_INET; 
		if(host=gethostbyname(par_host) ) 
		{ 
			memcpy( (char *)&dest_addr.sin_addr,host->h_addr,host->h_length); 
			//resolve address to hostname 
			if(host=gethostbyaddr(host->h_addr,4,PF_INET)) 
				par_host=host->h_name; 
		} 
		else if( dest_addr.sin_addr.s_addr=inet_addr(par_host)==INADDR_NONE) 
		{ 
			printf("Unkown host %s\n",par_host); 
			exit(1); 
		} 
 
 
		pid=getpid(); 
		for(i=0;i1) 
	{       sum+=*w++; 
	nleft-=2; 
	} 
	if( nleft==1) 
	{       *(unsigned char *)(&answer)=*(unsigned char *)w; 
	sum+=answer; 
	} 
	sum=(sum>>16)+(sum&0xffff); 
	sum+=(sum>>16); 
	answer=~sum; 
	return answer; 
} 
 
//打包 
int pack(int pack_no) 
{       
	int packsize; 
	struct icmp *icmp; 
 
	packsize=8+SEND_SIZE; 
	icmp=(struct icmp*)sendpacket; 
	icmp->icmp_type=ICMP_ECHO; 
	icmp->icmp_code=0; 
	icmp->icmp_cksum=0; 
	icmp->icmp_seq=pack_no; 
	icmp->icmp_id=pid; 
	icmp->icmp_data=GetTickCount(); 
	icmp->icmp_cksum=cal_chksum( (unsigned short *)icmp,packsize); /*校验算法*/ 
	return packsize; 
} 
 
//解包 
int unpack(unsigned char *buf,int len) 
{      
	struct ip *ip; 
	struct icmp *icmp; 
	double rtt; 
	int iphdrlen; 
 
	ip=(struct ip *)buf; 
	iphdrlen=ip->ip_hl*4;    
	icmp=(struct icmp *)(buf+iphdrlen);           
	if( (icmp->icmp_type==ICMP_ECHOREPLY) && (icmp->icmp_id==pid) ) 
	{ 
		len=len-iphdrlen-8;   
		rtt=GetTickCount()-icmp->icmp_data;  
		printf("Reply from %s: bytes=%d time=%.0fms TTL=%d icmp_seq=%u\n",             
			inet_ntoa(from_addr.sin_addr), 
			len, 
			rtt, 
			ip->ip_ttl, 
			icmp->icmp_seq); 
 
		return 1; 
	} 
 
	return 0; 
} 
 
//发送 
void send_packet() 
{   
	int packetsize; 
	static int pack_no=0; 
 
	packetsize=pack(pack_no++); 
	if( sendto(sockfd,(const char*)sendpacket,packetsize,0,(struct sockaddr *)&dest_addr,sizeof(dest_addr) )<0  ) 
		printf("Destination host unreachable.\n"); 
	// printf("send NO %d\n",pack_no-1); 
} 
 
//接收 
void recv_packet() 
{    
	int n,fromlen; 
	int success; 
 
	fromlen=sizeof(from_addr); 
	do 
	{ 
		if( (n=recvfrom(sockfd,(char*)recvpacket,sizeof(recvpacket),0,(struct sockaddr *)&from_addr,&fromlen)) >=0) 
			success=unpack(recvpacket,n); 
		else if (WSAGetLastError() == WSAETIMEDOUT) 
		{ 
			printf("Request timed out.\n"); 
			return; 
		} 
	}while(!success); 
 
}