xref: /openbsd-src/sbin/ping/ping.c (revision b2ea75c1b17e1a9a339660e7ed45cd24946b230e)
1 /*	$OpenBSD: ping.c,v 1.44 2001/01/12 20:07:05 deraadt Exp $	*/
2 /*	$NetBSD: ping.c,v 1.20 1995/08/11 22:37:58 cgd Exp $	*/
3 
4 /*
5  * Copyright (c) 1989, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * Mike Muuss.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. All advertising materials mentioning features or use of this software
20  *    must display the following acknowledgement:
21  *	This product includes software developed by the University of
22  *	California, Berkeley and its contributors.
23  * 4. Neither the name of the University nor the names of its contributors
24  *    may be used to endorse or promote products derived from this software
25  *    without specific prior written permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37  * SUCH DAMAGE.
38  */
39 
40 #ifndef lint
41 static char copyright[] =
42 "@(#) Copyright (c) 1989, 1993\n\
43 	The Regents of the University of California.  All rights reserved.\n";
44 #endif /* not lint */
45 
46 #ifndef lint
47 #if 0
48 static char sccsid[] = "@(#)ping.c	8.1 (Berkeley) 6/5/93";
49 #else
50 static char rcsid[] = "$OpenBSD: ping.c,v 1.44 2001/01/12 20:07:05 deraadt Exp $";
51 #endif
52 #endif /* not lint */
53 
54 /*
55  *			P I N G . C
56  *
57  * Using the InterNet Control Message Protocol (ICMP) "ECHO" facility,
58  * measure round-trip-delays and packet loss across network paths.
59  *
60  * Author -
61  *	Mike Muuss
62  *	U. S. Army Ballistic Research Laboratory
63  *	December, 1983
64  *
65  * Status -
66  *	Public Domain.  Distribution Unlimited.
67  * Bugs -
68  *	More statistics could always be gathered.
69  *	This program has to run SUID to ROOT to access the ICMP socket.
70  */
71 
72 #include <sys/param.h>
73 #include <sys/queue.h>
74 #include <sys/socket.h>
75 #include <sys/file.h>
76 #include <sys/time.h>
77 
78 #include <netinet/in_systm.h>
79 #include <netinet/in.h>
80 #include <netinet/ip.h>
81 #include <netinet/ip_icmp.h>
82 #include <netinet/ip_var.h>
83 #include <arpa/inet.h>
84 #include <netdb.h>
85 #include <signal.h>
86 #include <unistd.h>
87 #include <stdio.h>
88 #include <ctype.h>
89 #include <err.h>
90 #include <errno.h>
91 #include <string.h>
92 #include <stdlib.h>
93 
94 struct tvi {
95 	u_int	tv_sec;
96 	u_int	tv_usec;
97 };
98 
99 #define	DEFDATALEN	(64 - 8)		/* default data length */
100 #define	MAXIPLEN	60
101 #define	MAXICMPLEN	76
102 #define	MAXPAYLOAD	(IP_MAXPACKET - MAXIPLEN - 8) /* max ICMP payload size */
103 #define	MAXWAIT_DEFAULT	10			/* secs to wait for response */
104 #define	NROUTES		9			/* number of record route slots */
105 
106 #define	A(bit)		rcvd_tbl[(bit)>>3]	/* identify byte in array */
107 #define	B(bit)		(1 << ((bit) & 0x07))	/* identify bit in byte */
108 #define	SET(bit)	(A(bit) |= B(bit))
109 #define	CLR(bit)	(A(bit) &= (~B(bit)))
110 #define	TST(bit)	(A(bit) & B(bit))
111 
112 /* various options */
113 int options;
114 #define	F_FLOOD		0x001
115 #define	F_INTERVAL	0x002
116 #define	F_NUMERIC	0x004
117 #define	F_PINGFILLED	0x008
118 #define	F_QUIET		0x010
119 #define	F_RROUTE	0x020
120 #define	F_SO_DEBUG	0x040
121 #define	F_SO_DONTROUTE	0x080
122 #define	F_VERBOSE	0x100
123 #define	F_SADDR		0x200
124 #define	F_HDRINCL       0x400
125 #define	F_TTL		0x800
126 
127 /* multicast options */
128 int moptions;
129 #define	MULTICAST_NOLOOP	0x001
130 #define	MULTICAST_TTL		0x002
131 #define	MULTICAST_IF		0x004
132 
133 /*
134  * MAX_DUP_CHK is the number of bits in received table, i.e. the maximum
135  * number of received sequence numbers we can keep track of.  Change 128
136  * to 8192 for complete accuracy...
137  */
138 #define	MAX_DUP_CHK	(8 * 128)
139 int mx_dup_ck = MAX_DUP_CHK;
140 char rcvd_tbl[MAX_DUP_CHK / 8];
141 
142 struct sockaddr whereto;	/* who to ping */
143 struct sockaddr_in whence;		/* Which interface we come from */
144 int datalen = DEFDATALEN;
145 int s;				/* socket file descriptor */
146 u_char outpackhdr[IP_MAXPACKET]; /* Max packet size = 65535 */
147 u_char *outpack = outpackhdr+sizeof(struct ip);
148 char BSPACE = '\b';		/* characters written for flood */
149 char DOT = '.';
150 char *hostname;
151 int ident;			/* process id to identify our packets */
152 
153 /* counters */
154 long npackets;			/* max packets to transmit */
155 long nreceived;			/* # of packets we got back */
156 long nrepeats;			/* number of duplicates */
157 long ntransmitted;		/* sequence # for outbound packets = #sent */
158 double interval = 1;		/* interval between packets */
159 struct itimerval interstr;	/* interval structure for use with setitimer */
160 
161 /* timing */
162 int timing;			/* flag to do timing */
163 int maxwait = MAXWAIT_DEFAULT;	/* max seconds to wait for response */
164 quad_t tmin = 999999999;	/* minimum round trip time in millisec */
165 quad_t tmax = 0;		/* maximum round trip time in millisec */
166 quad_t tsum = 0;		/* sum of all times in millisec, for doing average */
167 quad_t tsumsq = 0;		/* sum of all times squared, for std. dev. */
168 
169 #ifdef SIGINFO
170 int reset_kerninfo;
171 #endif
172 
173 void fill __P((char *, char *));
174 void catcher(), prtsig(), finish(), summary(int);
175 int in_cksum __P((u_short *, int));
176 void pinger();
177 char *pr_addr __P((in_addr_t));
178 int check_icmph __P((struct ip *));
179 void pr_icmph __P((struct icmp *));
180 void pr_pack __P((char *, int, struct sockaddr_in *));
181 void pr_retip __P((struct ip *));
182 quad_t qsqrt __P((quad_t));
183 void usage();
184 
185 int
186 main(argc, argv)
187 	int argc;
188 	char **argv;
189 {
190 	struct timeval timeout;
191 	struct hostent *hp;
192 	struct sockaddr_in *to;
193 	struct protoent *proto;
194 	struct in_addr saddr;
195 	register int i;
196 	int ch, hold = 1, packlen, preload;
197 	int maxsize, maxsizelen, fdmasks;
198 	u_char *datap, *packet;
199 	char *target, hnamebuf[MAXHOSTNAMELEN];
200 	u_char ttl = MAXTTL, loop = 1, df = 0;
201 	int tos = 0;
202 #ifdef IP_OPTIONS
203 	char rspace[3 + 4 * NROUTES + 1];	/* record route space */
204 #endif
205 	fd_set *fdmaskp;
206 
207 	if (!(proto = getprotobyname("icmp")))
208 		errx(1, "unknown protocol icmp");
209 	if ((s = socket(AF_INET, SOCK_RAW, proto->p_proto)) < 0)
210 		err(1, "socket");
211 
212 	/* revoke privs */
213 	seteuid(getuid());
214 	setuid(getuid());
215 
216 	preload = 0;
217 	datap = &outpack[8 + sizeof(struct tvi)];
218 	while ((ch = getopt(argc, argv, "DI:LRS:c:dfh:i:l:np:qrs:T:t:vw:")) != -1)
219 		switch(ch) {
220 		case 'c':
221 			npackets = strtol(optarg, NULL, 0);
222 			if (npackets <= 0)
223 				errx(1, "bad number of packets to transmit: %s",
224 				    optarg);
225 			break;
226 		case 'D':
227 			options |= F_HDRINCL;
228 			df = -1;
229 			break;
230 		case 'd':
231 			options |= F_SO_DEBUG;
232 			break;
233 		case 'f':
234 			if (getuid())
235 				errx(1, "%s", strerror(EPERM));
236 			options |= F_FLOOD;
237 			setbuf(stdout, (char *)NULL);
238 			break;
239 		case 'I':
240 		case 'S':	/* deprecated */
241 			if (inet_aton(optarg, &saddr) == 0) {
242 				if ((hp = gethostbyname(optarg)) == NULL)
243 					errx(1, "bad interface address: %s",
244 					     optarg);
245 				memcpy(&saddr, hp->h_addr, sizeof(saddr));
246 			}
247 			options |= F_SADDR;
248 			break;
249 		case 'i':		/* wait between sending packets */
250 			interval = strtod(optarg, NULL);
251 
252 			if (interval <= 0 || interval >= INT_MAX)
253 				errx(1, "bad timing interval: %s", optarg);
254 
255 			if (interval < 1)
256 				if (getuid())
257 					errx(1, "%s: only root may use interval < 1s", strerror(EPERM));
258 
259 			if (interval < 0.01)
260 				interval = 0.01;
261 
262 			options |= F_INTERVAL;
263 			break;
264 		case 'L':
265 			moptions |= MULTICAST_NOLOOP;
266 			loop = 0;
267 			break;
268 		case 'l':
269 			if (getuid())
270 				errx(1, "%s", strerror(EPERM));
271 			preload = strtol(optarg, NULL, 0);
272 			if (preload < 0)
273 				errx(1, "bad preload value: %s", optarg);
274 			break;
275 		case 'n':
276 			options |= F_NUMERIC;
277 			break;
278 		case 'p':		/* fill buffer with user pattern */
279 			options |= F_PINGFILLED;
280 			fill((char *)datap, optarg);
281 				break;
282 		case 'q':
283 			options |= F_QUIET;
284 			break;
285 		case 'R':
286 			options |= F_RROUTE;
287 			break;
288 		case 'r':
289 			options |= F_SO_DONTROUTE;
290 			break;
291 		case 's':		/* size of packet to send */
292 			datalen = strtol(optarg, NULL, 0);
293 			if (datalen <= 0)
294 				errx(1, "bad packet size: %s", optarg);
295 			if (datalen > MAXPAYLOAD)
296 				errx(1, "packet size too large: %s", optarg);
297 			break;
298 		case 'T':
299 			options |= F_HDRINCL;
300 			tos = strtoul(optarg, NULL, 0);
301 			if (tos > 0xFF)
302 				errx(1, "bad tos value: %s", optarg);
303 			break;
304 		case 't':
305 			options |= F_TTL;
306 			ttl = strtol(optarg, NULL, 0);
307 			if (ttl <= 0)
308 				errx(1, "bad ttl value: %s", optarg);
309 			if (ttl > 255)
310 				errx(1, "ttl value too large: %s", optarg);
311 			break;
312 		case 'v':
313 			options |= F_VERBOSE;
314 			break;
315 		case 'w':
316 			maxwait = strtol(optarg, NULL, 0);
317 			if (maxwait <= 0)
318 				errx(1, "bad maxwait value: %s", optarg);
319 			break;
320 		default:
321 			usage();
322 		}
323 	argc -= optind;
324 	argv += optind;
325 
326 	if (argc != 1)
327 		usage();
328 
329 	memset(&interstr, 0, sizeof(interstr));
330 
331 	interstr.it_value.tv_sec = (long) interval;
332 	interstr.it_value.tv_usec =
333 		(long) ((interval - interstr.it_value.tv_sec) * 1000000);
334 
335 	target = *argv;
336 
337 	memset(&whereto, 0, sizeof(struct sockaddr));
338 	to = (struct sockaddr_in *)&whereto;
339 	to->sin_len = sizeof(struct sockaddr_in);
340 	to->sin_family = AF_INET;
341 	if (inet_aton(target, &to->sin_addr) != 0)
342 		hostname = target;
343 	else {
344 		hp = gethostbyname(target);
345 		if (!hp)
346 			errx(1, "unknown host: %s", target);
347 		to->sin_family = hp->h_addrtype;
348 		memcpy(&to->sin_addr, hp->h_addr, hp->h_length);
349 		(void)strlcpy(hnamebuf, hp->h_name, sizeof(hnamebuf));
350 		hostname = hnamebuf;
351 	}
352 
353 	if (options & F_FLOOD && options & F_INTERVAL)
354 		errx(1, "-f and -i options are incompatible");
355 
356 	if (datalen >= sizeof(struct tvi))	/* can we time transfer */
357 		timing = 1;
358 	packlen = datalen + MAXIPLEN + MAXICMPLEN;
359 	if (!(packet = (u_char *)malloc((u_int)packlen)))
360 		err(1, "malloc");
361 	if (!(options & F_PINGFILLED))
362 		for (i = sizeof(struct tvi); i < datalen; ++i)
363 			*datap++ = i;
364 
365 	ident = getpid() & 0xFFFF;
366 
367 	if (options & F_SADDR) {
368 		if (IN_MULTICAST(ntohl(to->sin_addr.s_addr)))
369 			moptions |= MULTICAST_IF;
370 		else {
371 			memset(&whence, 0, sizeof(whence));
372 			whence.sin_len = sizeof(whence);
373 			whence.sin_family = AF_INET;
374 			memcpy(&whence.sin_addr.s_addr, &saddr, sizeof(saddr));
375 			if (bind(s, (struct sockaddr*)&whence,
376 			    sizeof(whence)) < 0)
377 				err(1, "bind");
378 		}
379 	}
380 
381 	if (options & F_SO_DEBUG)
382 		(void)setsockopt(s, SOL_SOCKET, SO_DEBUG, (char *)&hold,
383 		    sizeof(hold));
384 	if (options & F_SO_DONTROUTE)
385 		(void)setsockopt(s, SOL_SOCKET, SO_DONTROUTE, (char *)&hold,
386 		    sizeof(hold));
387 
388 	if (options & F_TTL) {
389 		if (IN_MULTICAST(ntohl(to->sin_addr.s_addr)))
390 		    moptions |= MULTICAST_TTL;
391 		else
392 		    options |= F_HDRINCL;
393 	}
394 
395 	if (options & F_RROUTE && options & F_HDRINCL)
396 		errx(1, "-R option and -D or -T, or -t to unicast destinations"
397 		     " are incompatible");
398 
399 	if (options & F_HDRINCL) {
400 		struct ip *ip = (struct ip*)outpackhdr;
401 
402 		setsockopt(s, IPPROTO_IP, IP_HDRINCL, &hold, sizeof(hold));
403 		ip->ip_v = IPVERSION;
404 		ip->ip_hl = sizeof(struct ip) >> 2;
405 		ip->ip_tos = tos;
406 		ip->ip_id = 0;
407 		ip->ip_off = htons(df?IP_DF:0);
408 		ip->ip_ttl = ttl;
409 		ip->ip_p = proto->p_proto;
410 		ip->ip_src.s_addr = INADDR_ANY;
411 		ip->ip_dst = to->sin_addr;
412 	}
413 
414 	/* record route option */
415 	if (options & F_RROUTE) {
416 		if (IN_MULTICAST(ntohl(to->sin_addr.s_addr)))
417 			errx(1, "record route not valid to multicast destinations");
418 #ifdef IP_OPTIONS
419 		rspace[IPOPT_OPTVAL] = IPOPT_RR;
420 		rspace[IPOPT_OLEN] = sizeof(rspace)-1;
421 		rspace[IPOPT_OFFSET] = IPOPT_MINOFF;
422 		if (setsockopt(s, IPPROTO_IP, IP_OPTIONS, rspace,
423 		    sizeof(rspace)) < 0) {
424 			perror("ping: record route");
425 			exit(1);
426 		}
427 #else
428 		errx(1, "record route not available in this implementation");
429 #endif /* IP_OPTIONS */
430 	}
431 
432 	if ((moptions & MULTICAST_NOLOOP) &&
433 	    setsockopt(s, IPPROTO_IP, IP_MULTICAST_LOOP, &loop,
434 		       sizeof(loop)) < 0)
435 		err(1, "setsockopt IP_MULTICAST_LOOP");
436 	if ((moptions & MULTICAST_TTL) &&
437 	    setsockopt(s, IPPROTO_IP, IP_MULTICAST_TTL, &ttl,
438 		       sizeof(ttl)) < 0)
439 		err(1, "setsockopt IP_MULTICAST_TTL");
440 	if ((moptions & MULTICAST_IF) &&
441 	    setsockopt(s, IPPROTO_IP, IP_MULTICAST_IF, &saddr,
442 		       sizeof(saddr)) < 0)
443 		err(1, "setsockopt IP_MULTICAST_IF");
444 
445 	/*
446 	 * When trying to send large packets, you must increase the
447 	 * size of both the send and receive buffers...
448 	 */
449 	maxsizelen = sizeof maxsize;
450 	if (getsockopt(s, SOL_SOCKET, SO_SNDBUF, &maxsize, &maxsizelen) < 0)
451 		err(1, "getsockopt");
452 	if (maxsize < packlen &&
453 	    setsockopt(s, SOL_SOCKET, SO_SNDBUF, &packlen, sizeof(maxsize)) < 0)
454 		err(1, "setsockopt");
455 
456 	/*
457 	 * When pinging the broadcast address, you can get a lot of answers.
458 	 * Doing something so evil is useful if you are trying to stress the
459 	 * ethernet, or just want to fill the arp cache to get some stuff for
460 	 * /etc/ethers.
461 	 */
462 	(void)setsockopt(s, SOL_SOCKET, SO_RCVBUF, &packlen, sizeof(packlen));
463 
464 	if (to->sin_family == AF_INET)
465 		(void)printf("PING %s (%s): %d data bytes\n", hostname,
466 		    inet_ntoa(*(struct in_addr *)&to->sin_addr.s_addr),
467 		    datalen);
468 	else
469 		(void)printf("PING %s: %d data bytes\n", hostname, datalen);
470 
471 	(void)signal(SIGINT, finish);
472 	(void)signal(SIGALRM, catcher);
473 #ifdef SIGINFO
474 	(void)signal(SIGINFO, prtsig);
475 #endif
476 
477 	while (preload--)		/* fire off them quickies */
478 		pinger();
479 
480 	if ((options & F_FLOOD) == 0)
481 		catcher();		/* start things going */
482 
483 	fdmasks = howmany(s+1, NFDBITS) * sizeof(fd_mask);
484 	if ((fdmaskp = (fd_set *)malloc(fdmasks)) == NULL)
485 		err(1, "malloc");
486 
487 	for (;;) {
488 		struct sockaddr_in from;
489 		register int cc;
490 		int fromlen;
491 		sigset_t omask, nmask;
492 
493 		if (options & F_FLOOD) {
494 			pinger();
495 			timeout.tv_sec = 0;
496 			timeout.tv_usec = 10000;
497 			memset(fdmaskp, 0, fdmasks);
498 			FD_SET(s, fdmaskp);
499 			if (select(s + 1, (fd_set *)fdmaskp, (fd_set *)NULL,
500 			    (fd_set *)NULL, &timeout) < 1)
501 				continue;
502 		}
503 		fromlen = sizeof(from);
504 		if ((cc = recvfrom(s, (char *)packet, packlen, 0,
505 		    (struct sockaddr *)&from, &fromlen)) < 0) {
506 			if (errno == EINTR)
507 				continue;
508 			perror("ping: recvfrom");
509 			continue;
510 		}
511 		sigemptyset(&nmask);
512 		sigaddset(&nmask, SIGALRM);
513 		sigprocmask(SIG_BLOCK, &nmask, &omask);
514 		pr_pack((char *)packet, cc, &from);
515 		sigprocmask(SIG_SETMASK, &omask, NULL);
516 		if (npackets && nreceived >= npackets)
517 			break;
518 	}
519 	free(fdmaskp);
520 	finish();
521 	/* NOTREACHED */
522 	exit(0);	/* Make the compiler happy */
523 }
524 
525 /*
526  * catcher --
527  *	This routine causes another PING to be transmitted, and then
528  * schedules another SIGALRM for 1 second from now.
529  *
530  * bug --
531  *	Our sense of time will slowly skew (i.e., packets will not be
532  * launched exactly at 1-second intervals).  This does not affect the
533  * quality of the delay and loss statistics.
534  */
535 void
536 catcher()
537 {
538 	int waittime;
539 	int save_errno = errno;
540 
541 	pinger();
542 	(void)signal(SIGALRM, catcher);
543 	if (!npackets || ntransmitted < npackets)
544 		setitimer(ITIMER_REAL, &interstr, (struct itimerval *)0);
545 	else {
546 		if (nreceived) {
547 			waittime = 2 * tmax / 1000000;
548 			if (!waittime)
549 				waittime = 1;
550 		} else
551 			waittime = maxwait;
552 		(void)signal(SIGALRM, finish);
553 		(void)alarm((u_int)waittime);
554 	}
555 	errno = save_errno;
556 }
557 
558 /*
559  * Print statistics when SIGINFO is received.
560  * XXX not race safe
561  */
562 void
563 prtsig()
564 {
565 	int save_errno = errno;
566 
567 	summary(0);
568 	errno = save_errno;
569 }
570 
571 /*
572  * pinger --
573  *	Compose and transmit an ICMP ECHO REQUEST packet.  The IP packet
574  * will be added on by the kernel.  The ID field is our UNIX process ID,
575  * and the sequence number is an ascending integer.  The first 8 bytes
576  * of the data portion are used to hold a UNIX "timeval" struct in VAX
577  * byte-order, to compute the round-trip time.
578  */
579 void
580 pinger()
581 {
582 	register struct icmp *icp;
583 	register int cc;
584 	int i;
585 	char *packet = outpack;
586 
587 	icp = (struct icmp *)outpack;
588 	icp->icmp_type = ICMP_ECHO;
589 	icp->icmp_code = 0;
590 	icp->icmp_cksum = 0;
591 	icp->icmp_seq = htons(ntransmitted++);
592 	icp->icmp_id = ident;			/* ID */
593 
594 	CLR(ntohs(icp->icmp_seq) % mx_dup_ck);
595 
596 	if (timing) {
597 		struct timeval tv;
598 		struct tvi tvi;
599 
600 		(void)gettimeofday(&tv, (struct timezone *)NULL);
601 		tvi.tv_sec = htonl(tv.tv_sec);
602 		tvi.tv_usec = htonl(tv.tv_usec);
603 		memcpy((u_int *)&outpack[8], &tvi, sizeof tvi);
604 	}
605 
606 	cc = datalen + 8;			/* skips ICMP portion */
607 
608 	/* compute ICMP checksum here */
609 	icp->icmp_cksum = in_cksum((u_short *)icp, cc);
610 
611 	if (options & F_HDRINCL) {
612 		struct ip *ip = (struct ip*)outpackhdr;
613 
614 		packet = (char*)ip;
615 		cc += sizeof(struct ip);
616 		ip->ip_len = htons(cc);
617 		ip->ip_sum = in_cksum((u_short *)outpackhdr, cc);
618 	}
619 
620 	i = sendto(s, (char *)packet, cc, 0, &whereto,
621 		   sizeof(struct sockaddr));
622 
623 	if (i < 0 || i != cc)  {
624 		if (i < 0)
625 			perror("ping: sendto");
626 		(void)printf("ping: wrote %s %d chars, ret=%d\n",
627 		    hostname, cc, i);
628 	}
629 	if (!(options & F_QUIET) && options & F_FLOOD)
630 		(void)write(STDOUT_FILENO, &DOT, 1);
631 }
632 
633 /*
634  * pr_pack --
635  *	Print out the packet, if it came from us.  This logic is necessary
636  * because ALL readers of the ICMP socket get a copy of ALL ICMP packets
637  * which arrive ('tis only fair).  This permits multiple copies of this
638  * program to be run without having intermingled output (or statistics!).
639  */
640 void
641 pr_pack(buf, cc, from)
642 	char *buf;
643 	int cc;
644 	struct sockaddr_in *from;
645 {
646 	register struct icmp *icp;
647 	register in_addr_t l;
648 	register u_int i, j;
649 	register u_char *cp, *dp;
650 	static int old_rrlen;
651 	static char old_rr[MAX_IPOPTLEN];
652 	struct ip *ip, *ip2;
653 	struct timeval tv, tp;
654 	char *pkttime;
655 	quad_t triptime = 0;
656 	int hlen, hlen2, dupflag;
657 
658 	(void)gettimeofday(&tv, (struct timezone *)NULL);
659 
660 	/* Check the IP header */
661 	ip = (struct ip *)buf;
662 	hlen = ip->ip_hl << 2;
663 	if (cc < hlen + ICMP_MINLEN) {
664 		if (options & F_VERBOSE)
665 			warnx("packet too short (%d bytes) from %s", cc,
666 			  inet_ntoa(*(struct in_addr *)&from->sin_addr.s_addr));
667 		return;
668 	}
669 
670 	/* Now the ICMP part */
671 	cc -= hlen;
672 	icp = (struct icmp *)(buf + hlen);
673 	if (icp->icmp_type == ICMP_ECHOREPLY) {
674 		if (icp->icmp_id != ident)
675 			return;			/* 'Twas not our ECHO */
676 		++nreceived;
677 		if (timing) {
678 			struct tvi tvi;
679 
680 #ifndef icmp_data
681 			pkttime = (char *)&icp->icmp_ip;
682 #else
683 			pkttime = (char *)icp->icmp_data;
684 #endif
685 			memcpy(&tvi, pkttime, sizeof tvi);
686 			tp.tv_sec = ntohl(tvi.tv_sec);
687 			tp.tv_usec = ntohl(tvi.tv_usec);
688 
689 			timersub(&tv, &tp, &tv);
690 			triptime = (tv.tv_sec * 1000000) + tv.tv_usec;
691 			tsum += triptime;
692 			tsumsq += triptime * triptime;
693 			if (triptime < tmin)
694 				tmin = triptime;
695 			if (triptime > tmax)
696 				tmax = triptime;
697 		}
698 
699 		if (TST(ntohs(icp->icmp_seq) % mx_dup_ck)) {
700 			++nrepeats;
701 			--nreceived;
702 			dupflag = 1;
703 		} else {
704 			SET(ntohs(icp->icmp_seq) % mx_dup_ck);
705 			dupflag = 0;
706 		}
707 
708 		if (options & F_QUIET)
709 			return;
710 
711 		if (options & F_FLOOD)
712 			(void)write(STDOUT_FILENO, &BSPACE, 1);
713 		else {
714 			(void)printf("%d bytes from %s: icmp_seq=%u", cc,
715 			   inet_ntoa(*(struct in_addr *)&from->sin_addr.s_addr),
716 			   ntohs(icp->icmp_seq));
717 			(void)printf(" ttl=%d", ip->ip_ttl);
718 			if (timing)
719 				(void)printf(" time=%d.%03d ms",
720 				    (int)(triptime / 1000),
721 				    (int)(triptime % 1000));
722 			if (dupflag)
723 				(void)printf(" (DUP!)");
724 			/* check the data */
725 			cp = (u_char*)&icp->icmp_data[sizeof(struct tvi)];
726 			dp = &outpack[8 + sizeof(struct tvi)];
727 			for (i = 8 + sizeof(struct tvi); i < datalen;
728 			    ++i, ++cp, ++dp) {
729 				if (*cp != *dp) {
730 	(void)printf("\nwrong data byte #%d should be 0x%x but was 0x%x",
731 	    i, *dp, *cp);
732 					cp = (u_char*)&icp->icmp_data[0];
733 					for (i = 8; i < datalen; ++i, ++cp) {
734 						if ((i % 32) == 8)
735 							(void)printf("\n\t");
736 						(void)printf("%x ", *cp);
737 					}
738 					break;
739 				}
740 			}
741 		}
742 	} else {
743 		/* We've got something other than an ECHOREPLY */
744 		if (!(options & F_VERBOSE))
745 			return;
746 		ip2 = (struct ip *) (buf + hlen + sizeof (struct icmp));
747 		hlen2 = ip2->ip_hl << 2;
748 		if (cc >= hlen2 + 8 && check_icmph((struct ip *)(icp +
749 		    sizeof (struct icmp))) != 1)
750 			return;
751 		(void)printf("%d bytes from %s: ", cc,
752 		    pr_addr(from->sin_addr.s_addr));
753 		pr_icmph(icp);
754 	}
755 
756 	/* Display any IP options */
757 	cp = (u_char *)buf + sizeof(struct ip);
758 
759 	for (; hlen > (int)sizeof(struct ip); --hlen, ++cp)
760 		switch (*cp) {
761 		case IPOPT_EOL:
762 			hlen = 0;
763 			break;
764 		case IPOPT_LSRR:
765 			(void)printf("\nLSRR: ");
766 			hlen -= 2;
767 			j = *++cp;
768 			++cp;
769 			i = 0;
770 			if (j > IPOPT_MINOFF) {
771 				for (;;) {
772 					l = *++cp;
773 					l = (l<<8) + *++cp;
774 					l = (l<<8) + *++cp;
775 					l = (l<<8) + *++cp;
776 					if (l == 0)
777 						(void)printf("\t0.0.0.0");
778 					else
779 						(void)printf("\t%s",
780 						    pr_addr(ntohl(l)));
781 					hlen -= 4;
782 					j -= 4;
783 					i += 4;
784 					if (j <= IPOPT_MINOFF)
785 						break;
786 					if (i >= MAX_IPOPTLEN) {
787 						(void)printf("\t(truncated route)");
788 						break;
789 					}
790 					(void)putchar('\n');
791 				}
792 			}
793 			break;
794 		case IPOPT_RR:
795 			j = *++cp;		/* get length */
796 			i = *++cp;		/* and pointer */
797 			hlen -= 2;
798 			if (i > j)
799 				i = j;
800 			i -= IPOPT_MINOFF;
801 			if (i <= 0)
802 				continue;
803 			if (i == old_rrlen
804 			    && cp == (u_char *)buf + sizeof(struct ip) + 2
805 			    && !memcmp(cp, old_rr, i)
806 			    && !(options & F_FLOOD)) {
807 				(void)printf("\t(same route)");
808 				i = ((i + 3) / 4) * 4;
809 				hlen -= i;
810 				cp += i;
811 				break;
812 			}
813 			if (i < MAX_IPOPTLEN) {
814 				old_rrlen = i;
815 				memcpy(old_rr, cp, i);
816 			} else
817 				old_rrlen = 0;
818 
819 			(void)printf("\nRR: ");
820 			j = 0;
821 			for (;;) {
822 				l = *++cp;
823 				l = (l<<8) + *++cp;
824 				l = (l<<8) + *++cp;
825 				l = (l<<8) + *++cp;
826 				if (l == 0)
827 					(void)printf("\t0.0.0.0");
828 				else
829 					(void)printf("\t%s", pr_addr(ntohl(l)));
830 				hlen -= 4;
831 				i -= 4;
832 				j += 4;
833 				if (i <= 0)
834 					break;
835 				if (j >= MAX_IPOPTLEN) {
836 					(void)printf("\t(truncated route)");
837 					break;
838 				}
839 				(void)putchar('\n');
840 			}
841 			break;
842 		case IPOPT_NOP:
843 			(void)printf("\nNOP");
844 			break;
845 		default:
846 			(void)printf("\nunknown option %x", *cp);
847 			hlen = hlen + cp[1] - 1;
848 			cp = cp + cp[1] - 1;
849 			break;
850 		}
851 	if (!(options & F_FLOOD)) {
852 		(void)putchar('\n');
853 		(void)fflush(stdout);
854 	}
855 }
856 
857 /*
858  * in_cksum --
859  *	Checksum routine for Internet Protocol family headers (C Version)
860  */
861 int
862 in_cksum(addr, len)
863 	u_short *addr;
864 	int len;
865 {
866 	register int nleft = len;
867 	register u_short *w = addr;
868 	register int sum = 0;
869 	u_short answer = 0;
870 
871 	/*
872 	 * Our algorithm is simple, using a 32 bit accumulator (sum), we add
873 	 * sequential 16 bit words to it, and at the end, fold back all the
874 	 * carry bits from the top 16 bits into the lower 16 bits.
875 	 */
876 	while (nleft > 1)  {
877 		sum += *w++;
878 		nleft -= 2;
879 	}
880 
881 	/* mop up an odd byte, if necessary */
882 	if (nleft == 1) {
883 		*(u_char *)(&answer) = *(u_char *)w ;
884 		sum += answer;
885 	}
886 
887 	/* add back carry outs from top 16 bits to low 16 bits */
888 	sum = (sum >> 16) + (sum & 0xffff);	/* add hi 16 to low 16 */
889 	sum += (sum >> 16);			/* add carry */
890 	answer = ~sum;				/* truncate to 16 bits */
891 	return(answer);
892 }
893 
894 void
895 summary(header)
896 	int header;
897 {
898 	(void)putchar('\r');
899 	(void)fflush(stdout);
900 
901 	if (header)
902 		(void)printf("--- %s ping statistics ---\n", hostname);
903 
904 	(void)printf("%ld packets transmitted, ", ntransmitted);
905 	(void)printf("%ld packets received, ", nreceived);
906 	if (nrepeats)
907 		(void)printf("%ld duplicates, ", nrepeats);
908 	if (ntransmitted) {
909 		if (nreceived > ntransmitted)
910 			(void)printf("-- somebody's printing up packets!");
911 		else
912 			(void)printf("%d%% packet loss",
913 			    (int) (((ntransmitted - nreceived) * 100) /
914 			    ntransmitted));
915 	}
916 	(void)putchar('\n');
917 	if (nreceived && timing) {
918 		quad_t num = nreceived + nrepeats;
919 		quad_t avg = tsum / num;
920 		quad_t dev = qsqrt(tsumsq / num - avg * avg);
921 		(void)printf("round-trip min/avg/max/std-dev = "
922 		    "%d.%03d/%d.%03d/%d.%03d/%d.%03d ms\n",
923 		    (int)(tmin / 1000), (int)(tmin % 1000),
924 		    (int)(avg  / 1000), (int)(avg  % 1000),
925 		    (int)(tmax / 1000), (int)(tmax % 1000),
926 		    (int)(dev  / 1000), (int)(dev  % 1000));
927 	}
928 }
929 
930 quad_t
931 qsqrt(quad_t qdev)
932 {
933 	quad_t y, x = 1;
934 
935 	if (!qdev)
936 		return(0);
937 
938 	do { /* newton was a stinker */
939 		y = x;
940 		x = qdev / x;
941 		x += y;
942 		x /= 2;
943 	} while ((x - y) > 1 || (x - y) < -1);
944 
945 	return(x);
946 }
947 
948 /*
949  * finish --
950  *	Print out statistics, and give up.
951  */
952 void
953 finish()
954 {
955 	(void)signal(SIGINT, SIG_IGN);
956 
957 	summary(1);
958 	exit(nreceived ? 0 : 1);
959 }
960 
961 #ifdef notdef
962 static char *ttab[] = {
963 	"Echo Reply",		/* ip + seq + udata */
964 	"Dest Unreachable",	/* net, host, proto, port, frag, sr + IP */
965 	"Source Quench",	/* IP */
966 	"Redirect",		/* redirect type, gateway, + IP  */
967 	"Echo",
968 	"Time Exceeded",	/* transit, frag reassem + IP */
969 	"Parameter Problem",	/* pointer + IP */
970 	"Timestamp",		/* id + seq + three timestamps */
971 	"Timestamp Reply",	/* " */
972 	"Info Request",		/* id + sq */
973 	"Info Reply"		/* " */
974 };
975 #endif
976 
977 /*
978  * pr_icmph --
979  *	Print a descriptive string about an ICMP header.
980  */
981 void
982 pr_icmph(icp)
983 	struct icmp *icp;
984 {
985 	switch(icp->icmp_type) {
986 	case ICMP_ECHOREPLY:
987 		(void)printf("Echo Reply\n");
988 		/* XXX ID + Seq + Data */
989 		break;
990 	case ICMP_UNREACH:
991 		switch(icp->icmp_code) {
992 		case ICMP_UNREACH_NET:
993 			(void)printf("Destination Net Unreachable\n");
994 			break;
995 		case ICMP_UNREACH_HOST:
996 			(void)printf("Destination Host Unreachable\n");
997 			break;
998 		case ICMP_UNREACH_PROTOCOL:
999 			(void)printf("Destination Protocol Unreachable\n");
1000 			break;
1001 		case ICMP_UNREACH_PORT:
1002 			(void)printf("Destination Port Unreachable\n");
1003 			break;
1004 		case ICMP_UNREACH_NEEDFRAG:
1005 			if (icp->icmp_nextmtu != 0)
1006 				(void)printf("frag needed and DF set (MTU %d)\n",
1007 					ntohs(icp->icmp_nextmtu));
1008 			else
1009 				(void)printf("frag needed and DF set\n");
1010 			break;
1011 		case ICMP_UNREACH_SRCFAIL:
1012 			(void)printf("Source Route Failed\n");
1013 			break;
1014 		case ICMP_UNREACH_NET_UNKNOWN:
1015 			(void)printf("Network Unknown\n");
1016 			break;
1017 		case ICMP_UNREACH_HOST_UNKNOWN:
1018 			(void)printf("Host Unknown\n");
1019 			break;
1020 		case ICMP_UNREACH_ISOLATED:
1021 			(void)printf("Source Isolated\n");
1022 			break;
1023 		case ICMP_UNREACH_NET_PROHIB:
1024 			(void)printf("Dest. Net Administratively Prohibited\n");
1025 			break;
1026 		case ICMP_UNREACH_HOST_PROHIB:
1027 			(void)printf("Dest. Host Administratively Prohibited\n");
1028 			break;
1029 		case ICMP_UNREACH_TOSNET:
1030 			(void)printf("Destination Net Unreachable for TOS\n");
1031 			break;
1032 		case ICMP_UNREACH_TOSHOST:
1033 			(void)printf("Desination Host Unreachable for TOS\n");
1034 			break;
1035 		case ICMP_UNREACH_FILTER_PROHIB:
1036 			(void)printf("Route administratively prohibited\n");
1037 			break;
1038 		case ICMP_UNREACH_HOST_PRECEDENCE:
1039 			(void)printf("Host Precedence Violation\n");
1040 			break;
1041 		case ICMP_UNREACH_PRECEDENCE_CUTOFF:
1042 			(void)printf("Precedence Cutoff\n");
1043 			break;
1044 		default:
1045 			(void)printf("Dest Unreachable, Unknown Code: %d\n",
1046 			    icp->icmp_code);
1047 			break;
1048 		}
1049 		/* Print returned IP header information */
1050 #ifndef icmp_data
1051 		pr_retip(&icp->icmp_ip);
1052 #else
1053 		pr_retip((struct ip *)icp->icmp_data);
1054 #endif
1055 		break;
1056 	case ICMP_SOURCEQUENCH:
1057 		(void)printf("Source Quench\n");
1058 #ifndef icmp_data
1059 		pr_retip(&icp->icmp_ip);
1060 #else
1061 		pr_retip((struct ip *)icp->icmp_data);
1062 #endif
1063 		break;
1064 	case ICMP_REDIRECT:
1065 		switch(icp->icmp_code) {
1066 		case ICMP_REDIRECT_NET:
1067 			(void)printf("Redirect Network");
1068 			break;
1069 		case ICMP_REDIRECT_HOST:
1070 			(void)printf("Redirect Host");
1071 			break;
1072 		case ICMP_REDIRECT_TOSNET:
1073 			(void)printf("Redirect Type of Service and Network");
1074 			break;
1075 		case ICMP_REDIRECT_TOSHOST:
1076 			(void)printf("Redirect Type of Service and Host");
1077 			break;
1078 		default:
1079 			(void)printf("Redirect, Unknown Code: %d", icp->icmp_code);
1080 			break;
1081 		}
1082 		(void)printf("(New addr: %s)\n",
1083 		    inet_ntoa(icp->icmp_gwaddr));
1084 #ifndef icmp_data
1085 		pr_retip(&icp->icmp_ip);
1086 #else
1087 		pr_retip((struct ip *)icp->icmp_data);
1088 #endif
1089 		break;
1090 	case ICMP_ECHO:
1091 		(void)printf("Echo Request\n");
1092 		/* XXX ID + Seq + Data */
1093 		break;
1094 	case ICMP_ROUTERADVERT:
1095 		/* RFC1256 */
1096 		(void)printf("Router Discovery Advertisement\n");
1097 		(void)printf("(%d entries, lifetime %d seconds)\n",
1098 		    icp->icmp_num_addrs, ntohs(icp->icmp_lifetime));
1099 		break;
1100 	case ICMP_ROUTERSOLICIT:
1101 		/* RFC1256 */
1102 		(void)printf("Router Discovery Solicitation\n");
1103 		break;
1104 	case ICMP_TIMXCEED:
1105 		switch(icp->icmp_code) {
1106 		case ICMP_TIMXCEED_INTRANS:
1107 			(void)printf("Time to live exceeded\n");
1108 			break;
1109 		case ICMP_TIMXCEED_REASS:
1110 			(void)printf("Frag reassembly time exceeded\n");
1111 			break;
1112 		default:
1113 			(void)printf("Time exceeded, Unknown Code: %d\n",
1114 			    icp->icmp_code);
1115 			break;
1116 		}
1117 #ifndef icmp_data
1118 		pr_retip(&icp->icmp_ip);
1119 #else
1120 		pr_retip((struct ip *)icp->icmp_data);
1121 #endif
1122 		break;
1123 	case ICMP_PARAMPROB:
1124 		switch(icp->icmp_code) {
1125 		case ICMP_PARAMPROB_OPTABSENT:
1126 			(void)printf(
1127 			    "Parameter problem, required option absent: pointer = 0x%02x\n",
1128 			    ntohs(icp->icmp_hun.ih_pptr));
1129 			break;
1130 		default:
1131 			(void)printf("Parameter problem: pointer = 0x%02x\n",
1132 			    ntohs(icp->icmp_hun.ih_pptr));
1133 			break;
1134 		}
1135 #ifndef icmp_data
1136 		pr_retip(&icp->icmp_ip);
1137 #else
1138 		pr_retip((struct ip *)icp->icmp_data);
1139 #endif
1140 		break;
1141 	case ICMP_TSTAMP:
1142 		(void)printf("Timestamp\n");
1143 		/* XXX ID + Seq + 3 timestamps */
1144 		break;
1145 	case ICMP_TSTAMPREPLY:
1146 		(void)printf("Timestamp Reply\n");
1147 		/* XXX ID + Seq + 3 timestamps */
1148 		break;
1149 	case ICMP_IREQ:
1150 		(void)printf("Information Request\n");
1151 		/* XXX ID + Seq */
1152 		break;
1153 	case ICMP_IREQREPLY:
1154 		(void)printf("Information Reply\n");
1155 		/* XXX ID + Seq */
1156 		break;
1157 #ifdef ICMP_MASKREQ
1158 	case ICMP_MASKREQ:
1159 		(void)printf("Address Mask Request\n");
1160 		break;
1161 #endif
1162 #ifdef ICMP_MASKREPLY
1163 	case ICMP_MASKREPLY:
1164 		(void)printf("Address Mask Reply (Mask 0x%08x)\n",
1165 		    ntohl(icp->icmp_mask));
1166 		break;
1167 #endif
1168 	default:
1169 		(void)printf("Unknown ICMP type: %d\n", icp->icmp_type);
1170 	}
1171 }
1172 
1173 /*
1174  * pr_iph --
1175  *	Print an IP header with options.
1176  */
1177 void
1178 pr_iph(ip)
1179 	struct ip *ip;
1180 {
1181 	int hlen;
1182 	u_char *cp;
1183 
1184 	hlen = ip->ip_hl << 2;
1185 	cp = (u_char *)ip + 20;		/* point to options */
1186 
1187 	(void)printf("Vr HL TOS  Len   ID Flg  off TTL Pro  cks      Src      Dst Data\n");
1188 	(void)printf(" %1x  %1x  %02x %04x %04x",
1189 	    ip->ip_v, ip->ip_hl, ip->ip_tos, ip->ip_len, ip->ip_id);
1190 	(void)printf("   %1x %04x", ((ip->ip_off) & 0xe000) >> 13,
1191 	    (ip->ip_off) & 0x1fff);
1192 	(void)printf("  %02x  %02x %04x", ip->ip_ttl, ip->ip_p, ip->ip_sum);
1193 	(void)printf(" %s ", inet_ntoa(*(struct in_addr *)&ip->ip_src.s_addr));
1194 	(void)printf(" %s ", inet_ntoa(*(struct in_addr *)&ip->ip_dst.s_addr));
1195 	/* dump and option bytes */
1196 	while (hlen-- > 20) {
1197 		(void)printf("%02x", *cp++);
1198 	}
1199 	(void)putchar('\n');
1200 }
1201 
1202 /*
1203  * pr_addr --
1204  *	Return an ascii host address as a dotted quad and optionally with
1205  * a hostname.
1206  */
1207 char *
1208 pr_addr(a)
1209 	in_addr_t a;
1210 {
1211 	struct hostent *hp;
1212 	struct in_addr in;
1213 	static char buf[16+3+MAXHOSTNAMELEN];
1214 
1215 	in.s_addr = a;
1216 	if ((options & F_NUMERIC) ||
1217 	    !(hp = gethostbyaddr((char *)&in.s_addr, sizeof(in.s_addr), AF_INET)))
1218 		(void)snprintf(buf, sizeof buf, "%s", inet_ntoa(in));
1219 	else
1220 		(void)snprintf(buf, sizeof buf, "%s (%s)", hp->h_name,
1221 		    inet_ntoa(in));
1222 	return(buf);
1223 }
1224 
1225 /*
1226  * pr_retip --
1227  *	Dump some info on a returned (via ICMP) IP packet.
1228  */
1229 void
1230 pr_retip(ip)
1231 	struct ip *ip;
1232 {
1233 	int hlen;
1234 	u_char *cp;
1235 
1236 	pr_iph(ip);
1237 	hlen = ip->ip_hl << 2;
1238 	cp = (u_char *)ip + hlen;
1239 
1240 	if (ip->ip_p == 6)
1241 		(void)printf("TCP: from port %u, to port %u (decimal)\n",
1242 		    (*cp * 256 + *(cp + 1)), (*(cp + 2) * 256 + *(cp + 3)));
1243 	else if (ip->ip_p == 17)
1244 		(void)printf("UDP: from port %u, to port %u (decimal)\n",
1245 			(*cp * 256 + *(cp + 1)), (*(cp + 2) * 256 + *(cp + 3)));
1246 }
1247 
1248 void
1249 fill(bp, patp)
1250 	char *bp, *patp;
1251 {
1252 	register int ii, jj, kk;
1253 	int pat[16];
1254 	char *cp;
1255 
1256 	for (cp = patp; *cp; cp++)
1257 		if (!isxdigit(*cp))
1258 			errx(1, "patterns must be specified as hex digits");
1259 	ii = sscanf(patp,
1260 	    "%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x",
1261 	    &pat[0], &pat[1], &pat[2], &pat[3], &pat[4], &pat[5], &pat[6],
1262 	    &pat[7], &pat[8], &pat[9], &pat[10], &pat[11], &pat[12],
1263 	    &pat[13], &pat[14], &pat[15]);
1264 
1265 	if (ii > 0)
1266 		for (kk = 0;
1267 		    kk <= MAXPAYLOAD - (8 + sizeof(struct tvi) + ii);
1268 		    kk += ii)
1269 			for (jj = 0; jj < ii; ++jj)
1270 				bp[jj + kk] = pat[jj];
1271 	if (!(options & F_QUIET)) {
1272 		(void)printf("PATTERN: 0x");
1273 		for (jj = 0; jj < ii; ++jj)
1274 			(void)printf("%02x", bp[jj] & 0xFF);
1275 		(void)printf("\n");
1276 	}
1277 }
1278 
1279 /*
1280  * when we get types of ICMP message with parts of the orig. datagram
1281  * we want to try to assure ourselves that it is from this instance
1282  * of ping, and not say, a refused finger connection or something
1283  */
1284 int
1285 check_icmph(iph)
1286 	struct ip *iph;
1287 {
1288 	struct icmp *icmph;
1289 
1290 	/* only allow IP version 4 */
1291 	if (iph->ip_v != 4)
1292 		return 0;
1293 
1294 	/* Only allow ICMP */
1295 	if (iph->ip_p != IPPROTO_ICMP)
1296 		return 0;
1297 
1298 	icmph = (struct icmp *) (iph + (4 * iph->ip_hl));
1299 
1300 	/* make sure it is in response to an ECHO request */
1301 	if (icmph->icmp_type != 8)
1302 		return 0;
1303 
1304 	/* ok, make sure it has the right id on it */
1305 	if (icmph->icmp_hun.ih_idseq.icd_id != ident)
1306 		return 0;
1307 
1308 	return 1;
1309 }
1310 
1311 void
1312 usage()
1313 {
1314 	(void)fprintf(stderr,
1315 	    "usage: ping [-DdfLnqRrv] [-c count] [-I ifaddr] [-i wait]\n"
1316 	    "\t[-l preload] [-p pattern] [-s packetsize] [-t ttl]"
1317 	    " [-w maxwait] host\n");
1318 	exit(1);
1319 }
1320