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微软ping命令的源代码 |
出处：CnXHacker.Net |
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| [ 2005-09-29 10:29:01
] |
作者：佚名
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责任编辑：lujiezhen |
memset(icmp_data,0,MAX_PACKET);
fill_icmp_data(icmp_data,datasize);
while(1) {
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("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("timed out\n");
continue;
}
fprintf(stderr,"recvfrom failed: %d\n",WSAGetLastError());
ExitProcess(STATUS_FAILED);
}
decode_resp(recvbuf,bread,&from);
Sleep(1000);
}
return 0;
}
/*
The response is an IP packet. We must decode the IP header to locate
the ICMP data
*/
void 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;
}
if (icmphdr->i_id != (USHORT)GetCurrentProcessId()) {
fprintf(stderr,"someone else's packet!\n");
return ;
}
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");
}
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));
}
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