ping的源代码

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
// Module Name: Ping.c
//
// Code by Rise
//
// Command Line Options/Parameters:
// Ping [host] [packet-size]
//
// host String name of host to ping
// packet-size Integer size of packet to send (smaller than 1024 bytes)
//
//#pragma pack(1)

#define WIN32_LEAN_AND_MEAN
#include <winsock2.h>
#include <ws2tcpip.h>
#include <stdio.h>
#include <stdlib.h>

#define IP_RECORD_ROUTE 0x7
//
// IP header structure
//
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 short ttl; // Time to live
unsigned short proto; // Protocol (TCP, UDP, etc.)
unsigned short checksum; // IP checksum

unsigned int sourceIP;
unsigned int destIP;
}IpHeader;

#define ICMP_ECHO 8
#define ICMP_ECHOREPLY 0
#define ICMP_MIN 8 // Minimun 8-byte ICMP packet (header)

//
// ICMP header structure
//
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 standard header, but we reserve space for time
ULONG timestamp;
}IcmpHeader;

//
// IP option header – use with socket option IP_OPTIONS
//
typedef struct _ipoptionhdr
{
unsigned char code; // Option type
unsigned char len; // Length of option hdr
unsigned char prt; // Offset into options
unsigned long addr[9]; // List of IP addrs
}IpOptionHeader;
#define DEF_PACKET_SIZE 32 // Default packet size
#define MAX_PACKET 1024 // Max ICMP packet size
#define MAX_IP_HDR_SIZE 60 // Max IP header size w/options

BOOL bRecordRoute;
int datasize;
char* lpdest;

//
// Function: usage
//
// Description:
// Print usage information
//
void usage(char* progname)
{
printf(“usage: ping -r <host> [data size]\n”);
printf(“ -r record route\n”);
printf(“ host remote machine to Ping\n”);
printf(“ datasize can be up to 1 KB\n”);
ExitProcess(-1);
}

//
// Function: FillICMPData
//
// Description:
// Helper function to fill in various fields for our ICMP request
//
void FillICMPData(char* icmp_data, int datasize)
{
IcmpHeader* icmp_hdr = NULL;
char* datapart = NULL;

icmp_hdr = (IcmpHeader*)icmp_data;
icmp_hdr->i_type = ICMP_ECHO; // Request an 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));
}

//
// Function: checksum
//
// Description:
// This funcion calculates the 16-bit one’s complement sum
// of the supplied buffer (ICMP)header
//
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);
}

//
// Function: DecodeIPOptions
//
// Description:
// If the IP option header is present. find the IP options
// within the IP header and print the record route option
// values
//
void DecodeIPOptions(charbuf,int bytes)
{
IpOptionHeader* ipopt = NULL;
IN_ADDR inaddr;
int i;
HOSTENT host = NULL;

ipopt = (IpOptionHeader)(buf + 20);

printf(“RR: ”);
for(i=0;i<(ipopt->prt/4)-1;i++)
{
inaddr.S_un.S_addr = ipopt->addr[i];
if(i != 0 )
printf(“ ”);
host = gethostbyaddr((char*)&inaddr.S_un.S_addr, sizeof(inaddr.S_un.S_addr), AF_INET);
if(host)
printf(“(%-15s) %s\n”, inet_ntoa(inaddr), host->h_name);
else
printf(“(%-15s)\n”, inet_ntoa(inaddr));
}
return;
}

//
// Function: DecodeICMPHeader
//
// Description:
// The response is an IP packet. We must decode the IP header to locate the ICMP data.
//
void DecodeICMPHeader(char* buf, int bytes, struct sockaddr_in from)
{
IpHeader iphdr = NULL;
IcmpHeader* icmphdr = NULL;
unsigned short iphdrlen;
DWORD tick;
static int icmpcount = 0;

iphdr = (IpHeader*)buf;
// Number of 32-bit words * 4 = bytes
iphdrlen = iphdr->h_len * 4;
tick = GetTickCount();

if((iphdrlen == MAX_IP_HDR_SIZE)&&(!icmpcount))
DecodeIPOptions(buf,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)
{
printf(“nonecho type %d recvd\n”, icmphdr->i_type);
return;
}
// Make sure this is an ICMP reply to something we sent!
//
if(icmphdr->i_id != (USHORT)GetCurrentProcessId())
{
printf(“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”, tick-icmphdr->timestamp);
printf(“\n”);

icmpcount++;
return;
}

void ValidateArgs(int argc, char argv)
{
int i;
bRecordRoute = FALSE;
lpdest = NULL;
datasize = DEF_PACKET_SIZE;

for(i = 1; i < argc; i++)
{
if((argv[i][0] == ‘-‘)||(argv[i][0] == ‘/‘))
{
switch(tolower(argv[i][1]))
{
case ‘r’: // Record route option
bRecordRoute = TRUE;
break;
default:
usage(argv[0]);
break;
}
}
else if(isdigit(argv[i][0]))
datasize = atoi(argv[i]);
else
lpdest = argv[i];
}
}

//
// Function: main
//
// Description
// Set up the ICMP raw socket, and create the ICMP header. Add
// the appropriate IP ooption header, and start sending ICMP
// echo requests to the endpoint. For each send and receive.
// we set a timeout value so that we don’t wait forever for a
// response in case the endpoint is not responding. When we
// receive a packet. decode it.
//
int main(int argc, char argv)
{
WSADATA wsaData;
SOCKET sockRaw = INVALID_SOCKET;
struct sockaddr_in dest, from;
int bread, fromlen = sizeof(from), timeout = 1000, ret;
char icmp_data = NULL, recvbuf = NULL;
unsigned int addr = 0;
USHORT seq_no = 0;
struct hostent hp = NULL;
IpOptionHeader ipopt;

if(WSAStartup(MAKEWORD(2, 2), &wsaData) != 0)
{
printf(“WSAStartup() failed: %d\n”, GetLastError());
return -1;
}
ValidateArgs(argc,argv);
sockRaw = WSASocket(AF_INET, SOCK_RAW, IPPROTO_ICMP, NULL, 0, WSA_FLAG_OVERLAPPED);
if(sockRaw == INVALID_SOCKET)
{
printf(“WSASocket() failed: %d\n”, WSAGetLastError());
return -1;
}
if(bRecordRoute)
{
// Setup the IP option header to go out on every ICMP packet
//
ZeroMemory(&ipopt, sizeof(ipopt));
ipopt.code = IP_RECORD_ROUTE; // Record route option
ipopt.prt = 4; // Point to the first addr offset
ipopt.len = 39; // Length of option header

ret = setsockopt(sockRaw, IPPROTO_IP, IP_OPTIONS, (char)&ipopt, sizeof(ipopt));
if(ret == SOCKET_ERROR)
{
printf(“setsockopt(IP_OPTIONs) failed: %d\n”,WSAGetLastError());
}
}
// Set the send/recv timeout values
//
bread = setsockopt(sockRaw, SOL_SOCKET, SO_RCVTIMEO, (char)&timeout, sizeof(timeout));
if(bread == SOCKET_ERROR)
{
printf(“setsockopt(SO_RCVTIME0)failed: %d\n”, WSAGetLastError());
return -1;
}
timeout = 1000;
bread = setsockopt(sockRaw, SOL_SOCKET, SO_SNDTIMEO, (char)&timeout, sizeof(timeout));
if(bread == SOCKET_ERROR)
{
printf(“setsockopt(SO_SNDTIME0) failed: %d\n”, WSAGetLastError());
return -1;
}
memset(&dest, 0, sizeof(dest));
//
// Resolve the endpoint`s name if necessary
//
dest.sin_family = AF_INET;
if((dest.sin_addr.s_addr = inet_addr(lpdest)) == INADDR_NONE)
{
if((hp = gethostbyname(lpdest)) != NULL)
{
memcpy(&(dest.sin_addr), hp->h_addr, hp->h_length);
dest.sin_family = hp->h_addrtype;
printf(“dest.sin_addr = %s\n”, inet_ntoa(dest.sin_addr));
}
else
{
printf(“gethostbyname() failed: %d\n”,WSAGetLastError());
return -1;
}
}

//
// Create the ICMP packet
//
datasize += sizeof(IcmpHeader);
icmp_data = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, MAX_PACKET);
recvbuf = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, MAX_PACKET);
if(!icmp_data)
{
printf(“HeapAlloc() failed: %d\n”,GetLastError());
return -1;
}
memset(icmp_data, 0, MAX_PACKET);
FillICMPData(icmp_data, datasize);
//
// Start sending/receiving ICMP packets
//
while(1)
{
static int nCount = 0;
int bwrote;

if(nCount++ ==4)
break;
((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, 0, (struct sockaddr*)&dest, sizeof(dest));

bwrote = sendto(sockRaw, icmp_data, datasize, 0, (struct sockaddr*)&dest, sizeof(dest));
if(bwrote == SOCKET_ERROR)
{
if(WSAGetLastError() == WSAETIMEDOUT)
{
printf(“timed out\n”);
continue;
}
printf(“recvfrom() failed: %d\n”, WSAGetLastError());
return -1;
}
if(bwrote < datasize)
{
printf(“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;
}
printf(“recvfrom() failed: %d\n”, WSAGetLastError());
}
DecodeICMPHeader(recvbuf, bread, &from);

Sleep(1000);
}

//Cleanup
//
if(sockRaw != INVALID_SOCKET)
closesocket(sockRaw);
HeapFree(GetProcessHeap(), 0, recvbuf);
HeapFree(GetProcessHeap(), 0, icmp_data);

WSACleanup();
return 0;
}