ping程序源代码完整版（转载）

作者:侯志江     单位:天津大学软件学院       E-mail :[email protected]   日期:2005年1月1日     
内容简介: 编写自己的一个ping程序,可以说是许多人迈出网络编程的第一步吧!!这个ping程序的源代码经过我的修改和调试,基本上可以取代windows中自带的ping程序. 各个模块后都有我的详细注释和修改日志,希望能够对大家的学习有所帮助!!

/* 本程序的主要源代码来自MSDN网站, 笔者只是做了一些改进和注释! 另外需要注意的是在Build之前,必须加入ws2_32.lib库文件,否则会提示"error LNK2001:"的错误！*/ 
Version 1.1 修改记录:
     <1> 解决了socket阻塞的问题,从而能够正确地处理超时的请求! 
     <2> 增加了由用户控制发送ICMP包的数目的功能(即命令的第二个参数)
     <3> 增加了对ping结果的统计功能.  
                                                          

#pragma pack(4) 
#include   "winsock2.h"
#include   "stdlib.h"
#include   "stdio.h"
#define ICMP_ECHO 8 
#define ICMP_ECHOREPLY 0 
#define ICMP_MIN 8 // minimum 8 byte icmp packet (just header) 
/* The IP header */ 
typedef struct iphdr { 
unsigned int h_len:4; // length of the header 
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; 
USHORT i_seq; 
/* 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    /* 发送数据报的个数 */
#define MAX_PACKET 1024 
#define xmalloc(s) HeapAlloc(GetProcessHeap(),HEAP_ZERO_MEMORY,(s)) 
#define xfree(p) HeapFree (GetProcessHeap(),0,(p)) 
void fill_icmp_data(char *, int); 
USHORT checksum(USHORT *, int); 
int decode_resp(char *,int ,struct sockaddr_in *); 
void Usage(char *progname){ 
fprintf(stderr,"Usage:/n"); 
fprintf(stderr,"%s [number of packets] [data_size]/n",progname); 
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(argv[0]); 
} 
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)); 
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)); 
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]); 
if (!hp){ 
addr = inet_addr(argv[1]); 
} 
if ((!hp) && (addr == INADDR_NONE) ) { 
fprintf(stderr,"Unable to resolve %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]);
if(times == 0)
  times=DEF_PACKET_NUMBER;
}
else
    times=DEF_PACKET_NUMBER;
if (argc >3) 
{ 
datasize = atoi(argv[3]); 
    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; 
}
} 
else 
    datasize = DEF_PACKET_SIZE; 
datasize += sizeof(IcmpHeader); 
icmp_data = (char*)xmalloc(MAX_PACKET); 
recvbuf = (char*)xmalloc(MAX_PACKET); 
if (!icmp_data) { 
fprintf(stderr,"HeapAlloc failed %d/n",GetLastError()); 
ExitProcess(STATUS_FAILED); 
} 

memset(icmp_data,0,MAX_PACKET); 
fill_icmp_data(icmp_data,datasize); 
//
//显示提示信息
//
fprintf(stdout,"/nPinging %s ..../n/n",dest_ip);

for(int i=0;i{ 
int bwrote; 
((IcmpHeader*)icmp_data)->i_cksum = 0; 
((IcmpHeader*)icmp_data)->timestamp = GetTickCount(); 
((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; 
} 
/* 
The response is an IP packet. We must decode the IP header to locate 
the ICMP data 
*/ 
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) { 
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, inet_ntoa(from->sin_addr)); 
printf(" icmp_seq = %d. ",icmphdr->i_seq); 
printf(" time: %d ms ",GetTickCount()-icmphdr->timestamp); 
printf("/n");
return 0; 
} 

USHORT checksum(USHORT *buffer, int size) { 
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_hdr->i_code = 0; 
icmp_hdr->i_id = (USHORT)GetCurrentProcessId(); 
icmp_hdr->i_cksum = 0; 
icmp_hdr->i_seq = 0; 
datapart = icmp_data + sizeof(IcmpHeader); 
// 
// Place some junk in the buffer. 
// 
memset(datapart,''E'', datasize - sizeof(IcmpHeader)); 
} 
/******************* 附: ping命令执行时显示的画面 ****************/
*  C:/Documents and settings/houzhijiang>ping   236.56.54.12                              * *                                                                                                                          *
*  Pinging 236.56.54.12 with 32 bytes of data:                                                      *
*                                                                                                                          * 
*  Request timed out.                                                                                            *
*  Request timed out.                                                                                            *
*  Request timed out.                                                                                            *
*  Request timed out.                                                                                            * 
*                                                                                                                          *
*  Ping statistics for 236.56.54.12:                                                                        *
*     Packets: Sent = 4, Received = 0, Lost = 4 (100% loss),                                *
*                                                                                                                         *
/**************************************************************/
/**************************************************************/
*  C:/Documents and Settings/houzhijiang>ping 127.0.0.1                                    *
*                                                                                                                         *
*  Pinging 127.0.0.1 with 32 bytes of data:                                                           *
*                                                                                                                         *
*  Reply from 127.0.0.1: bytes=32 time<1ms TTL=128                                      *
*  Reply from 127.0.0.1: bytes=32 time<1ms TTL=128                                      *
*  Reply from 127.0.0.1: bytes=32 time<1ms TTL=128                                      *
*  Reply from 127.0.0.1: bytes=32 time<1ms TTL=128                                      *
*                                                                                                                         *
*  Ping statistics for 127.0.0.1:                                                                             *
*     Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),                                   *
*  Approximate round trip times in milli-seconds:                                                  *
*     Minimum = 0ms, Maximum = 0ms, Average = 0ms                                       *
*                                                                                                                         *
/**************************************************************/