编程实现ping命令

物联网工程学院实验报告课程名称《计算机网络》实验名称编程实现ping命令实验日期2023-5-1班级计科姓名学号03040实验报告要求1．实验名称2．实验要求3．实验环境4．实验步骤(写明实验结果)5．实验体会实验截图：实验代码：

#pragmapack(4)

#include

"winsock2.h"

#include

"stdlib.h"

#include

"stdio.h"

#defineICMP_ECHO8

#defineICMP_ECHOREPLY0

#defineICMP_MIN8//minimum8byteicmppacket(justheader)

/*TheIPheader*/

typedefstructiphdr{

unsignedinth_len:4;//lengthoftheheader

unsignedintversion:4;//VersionofIP

unsignedchartos;//Typeofservice

unsignedshorttotal_len;//totallengthofthepacket

typedefstructicmphdr{

BYTEi_type;

BYTEi_code;/*typesubcode*/

USHORTi_cksum;

USHORTi_id;

USHORTi_seq;

/*Thisisnotthestdheader,butwereservespacefortime*/

ULONGtimestamp;

}IcmpHeader;

#defineSTATUS_FAILED0xFFFF

#defineDEF_PACKET_SIZE

32

#defineDEF_PACKET_NUMBER

4

/*发送数据报的个数*/

#defineMAX_PACKET1024

#definexmalloc(s)HeapAlloc(GetProcessHeap(),HEAP_ZERO_MEMORY,(s))

#definexfree(p)HeapFree(GetProcessHeap(),0,(p))

voidfill_icmp_data(char*,int);

USHORTchecksum(USHORT*,int);

intdecode_resp(char*,int,structsockaddr_in*);

voidUsage(char*progname){

fprintf(stderr,"Usage:\n");

fprintf(stderr,"%s[numberofpackets][data_size]\n",progname);

fprintf(stderr,"datasizecanbeupto1Kb\n");

ExitProcess(STATUS_FAILED);

}

intmain(intargc,char**argv){

WSADATAwsaData;

SOCKETsockRaw;

structsockaddr_indest,from;

structhostent*hp;

intbread,datasize,times;

intfromlen=sizeof(from);

inttimeout=1000;

intstatistic=0;

/*用于统计结果*/

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,"failedtosetrecvtimeout:%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,"failedtosetsendtimeout:%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,"Unabletoresolve%s\n",argv[1]);

ExitProcess(STATUS_FAILED);

}

if(hp!=NULL)

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_sizeistoolarge!\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,"HeapAllocfailed%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);

continue;

}

fprintf(stderr,"sendtofailed:%d\n",WSAGetLastError());

ExitProcess(STATUS_FAILED);

}

if(bwrote<datasize){

fprintf(stdout,"Wrote%dbytes\n",bwrote);

}

bread=recvfrom(sockRaw,recvbuf,MAX_PACKET,0,(structsockaddr*)&from,&fromlen);

if(bread==SOCKET_ERROR){

if(WSAGetLastError()==WSAETIMEDOUT){

printf("Requesttimedout.\n");

continue;

}

fprintf(stderr,"recvfromfailed:%d\n",WSAGetLastError());

ExitProcess(STATUS_FAILED);

}

if(!decode_resp(recvbuf,bread,&from))

statistic++;/*成功接收的数目++*/

Sleep(1000);

}

/*

Displaythestatisticresult

*/

fprintf(stdout,"\nPingstatisticsfor%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);

unsignedshortiphdrlen;

iphdr=(IpHeader*)buf;

iphdrlen=(iphdr->h_len)*4;//numberof32-bitwords*4=bytes

if(bytes<iphdrlen+ICMP_MIN){

printf("Toofewbytesfrom%s\n",inet_ntoa(from->sin_addr));

}

icmphdr=(IcmpHeader*)(buf+iphdrlen);

if(icmphdr->i_type!=ICMP_ECHOREPLY){

fprintf(stderr,"non-echotype%drecvd\n",icmphdr->i_type);

return1;

}

if(icmphdr->i_id!=(USHORT)GetCurrentProcessId()){

fprintf(stderr,"someoneelse''spacket!\n");

return1;

}

printf("%dbytesfrom%s:",bytes,inet_ntoa(from->sin_addr));

printf("icmp_seq=%d.",icmphdr->i_seq);

printf("time:%dms",GetTickCount()-icmphdr->timestamp);

printf("\n");

return0;

}

USHORTchecksum(USHORT*buffer,intsize){

unsignedlongcksum=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);

}

/*

HelperfunctiontofillinvariousstuffinourICMPrequest.

*/

voidfill_icmp_data(char*