xref: /netbsd-src/sbin/ping/ping.c (revision ae9172d6cd9432a6a1a56760d86b32c57a66c39c)
1 /*
2  * Copyright (c) 1989, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Mike Muuss.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #ifndef lint
38 static char copyright[] =
39 "@(#) Copyright (c) 1989, 1993\n\
40 	The Regents of the University of California.  All rights reserved.\n";
41 #endif /* not lint */
42 
43 #ifndef lint
44 /*static char sccsid[] = "from: @(#)ping.c	8.1 (Berkeley) 6/5/93";*/
45 static char *rcsid = "$Id: ping.c,v 1.12 1994/12/18 00:20:51 cgd Exp $";
46 #endif /* not lint */
47 
48 /*
49  *			P I N G . C
50  *
51  * Using the InterNet Control Message Protocol (ICMP) "ECHO" facility,
52  * measure round-trip-delays and packet loss across network paths.
53  *
54  * Author -
55  *	Mike Muuss
56  *	U. S. Army Ballistic Research Laboratory
57  *	December, 1983
58  *
59  * Status -
60  *	Public Domain.  Distribution Unlimited.
61  * Bugs -
62  *	More statistics could always be gathered.
63  *	This program has to run SUID to ROOT to access the ICMP socket.
64  */
65 
66 #include <sys/param.h>
67 #include <sys/queue.h>
68 #include <sys/socket.h>
69 #include <sys/file.h>
70 #include <sys/time.h>
71 #include <sys/signal.h>
72 
73 #include <netinet/in_systm.h>
74 #include <netinet/in.h>
75 #include <netinet/ip.h>
76 #include <netinet/ip_icmp.h>
77 #include <netinet/ip_var.h>
78 #include <arpa/inet.h>
79 #include <netdb.h>
80 #include <unistd.h>
81 #include <stdio.h>
82 #include <ctype.h>
83 #include <err.h>
84 #include <errno.h>
85 #include <string.h>
86 #include <stdlib.h>
87 
88 #define	DEFDATALEN	(64 - 8)	/* default data length */
89 #define	MAXIPLEN	60
90 #define	MAXICMPLEN	76
91 #define	MAXPACKET	(65536 - 60 - 8)/* max packet size */
92 #define	MAXWAIT		10		/* max seconds to wait for response */
93 #define	NROUTES		9		/* number of record route slots */
94 
95 #define	A(bit)		rcvd_tbl[(bit)>>3]	/* identify byte in array */
96 #define	B(bit)		(1 << ((bit) & 0x07))	/* identify bit in byte */
97 #define	SET(bit)	(A(bit) |= B(bit))
98 #define	CLR(bit)	(A(bit) &= (~B(bit)))
99 #define	TST(bit)	(A(bit) & B(bit))
100 
101 /* various options */
102 int options;
103 #define	F_FLOOD		0x001
104 #define	F_INTERVAL	0x002
105 #define	F_NUMERIC	0x004
106 #define	F_PINGFILLED	0x008
107 #define	F_QUIET		0x010
108 #define	F_RROUTE	0x020
109 #define	F_SO_DEBUG	0x040
110 #define	F_SO_DONTROUTE	0x080
111 #define	F_VERBOSE	0x100
112 
113 /* multicast options */
114 int moptions;
115 #define	MULTICAST_NOLOOP	0x001
116 #define	MULTICAST_TTL		0x002
117 #define	MULTICAST_IF		0x004
118 
119 /*
120  * MAX_DUP_CHK is the number of bits in received table, i.e. the maximum
121  * number of received sequence numbers we can keep track of.  Change 128
122  * to 8192 for complete accuracy...
123  */
124 #define	MAX_DUP_CHK	(8 * 128)
125 int mx_dup_ck = MAX_DUP_CHK;
126 char rcvd_tbl[MAX_DUP_CHK / 8];
127 
128 struct sockaddr whereto;	/* who to ping */
129 int datalen = DEFDATALEN;
130 int s;				/* socket file descriptor */
131 u_char outpack[MAXPACKET];
132 char BSPACE = '\b';		/* characters written for flood */
133 char DOT = '.';
134 char *hostname;
135 int ident;			/* process id to identify our packets */
136 
137 /* counters */
138 long npackets;			/* max packets to transmit */
139 long nreceived;			/* # of packets we got back */
140 long nrepeats;			/* number of duplicates */
141 long ntransmitted;		/* sequence # for outbound packets = #sent */
142 int interval = 1;		/* interval between packets */
143 
144 /* timing */
145 int timing;			/* flag to do timing */
146 double tmin = 999999999.0;	/* minimum round trip time */
147 double tmax = 0.0;		/* maximum round trip time */
148 double tsum = 0.0;		/* sum of all times, for doing average */
149 
150 void fill __P((char *, char *));
151 void catcher(), finish();
152 int in_cksum __P((u_short *, int));
153 void pinger();
154 char *pr_addr __P((u_long));
155 void pr_icmph __P((struct icmp *));
156 void pr_pack __P((char *, int, struct sockaddr_in *));
157 void pr_retip __P((struct ip *));
158 void tvsub __P((struct timeval *, struct timeval *));
159 void usage();
160 
161 int
162 main(argc, argv)
163 	int argc;
164 	char **argv;
165 {
166 	extern int errno, optind;
167 	extern char *optarg;
168 	struct timeval timeout;
169 	struct hostent *hp;
170 	struct sockaddr_in *to;
171 	struct protoent *proto;
172 	struct in_addr ifaddr;
173 	register int i;
174 	int ch, fdmask, hold, packlen, preload;
175 	u_char *datap, *packet;
176 	char *target, hnamebuf[MAXHOSTNAMELEN];
177 	u_char ttl, loop = 1;
178 #ifdef IP_OPTIONS
179 	char rspace[3 + 4 * NROUTES + 1];	/* record route space */
180 #endif
181 
182 	preload = 0;
183 	datap = &outpack[8 + sizeof(struct timeval)];
184 	while ((ch = getopt(argc, argv, "I:LRc:dfh:i:l:np:qrs:t:v")) != EOF)
185 		switch(ch) {
186 		case 'c':
187 			npackets = atoi(optarg);
188 			if (npackets <= 0)
189 				errx(1, "bad number of packets to transmit: %s",
190 				    optarg);
191 			break;
192 		case 'd':
193 			options |= F_SO_DEBUG;
194 			break;
195 		case 'f':
196 			if (getuid())
197 				errx(1, "%s", strerror(EPERM));
198 			options |= F_FLOOD;
199 			setbuf(stdout, (char *)NULL);
200 			break;
201 		case 'I':
202 			if (inet_aton(optarg, &ifaddr) == 0)
203 				errx(1, "bad interface address: %s", optarg);
204 			moptions |= MULTICAST_IF;
205 			break;
206 		case 'i':		/* wait between sending packets */
207 			interval = atoi(optarg);
208 			if (interval <= 0)
209 				errx(1, "bad timing interval: %s", optarg);
210 			options |= F_INTERVAL;
211 			break;
212 		case 'L':
213 			moptions |= MULTICAST_NOLOOP;
214 			loop = 0;
215 			break;
216 		case 'l':
217 			preload = atoi(optarg);
218 			if (preload < 0)
219 				errx(1, "bad preload value: %s", optarg);
220 			break;
221 		case 'n':
222 			options |= F_NUMERIC;
223 			break;
224 		case 'p':		/* fill buffer with user pattern */
225 			options |= F_PINGFILLED;
226 			fill((char *)datap, optarg);
227 				break;
228 		case 'q':
229 			options |= F_QUIET;
230 			break;
231 		case 'R':
232 			options |= F_RROUTE;
233 			break;
234 		case 'r':
235 			options |= F_SO_DONTROUTE;
236 			break;
237 		case 's':		/* size of packet to send */
238 			datalen = atoi(optarg);
239 			if (datalen <= 0)
240 				errx(1, "bad packet size: %s", optarg);
241 			if (datalen > MAXPACKET)
242 				errx(1, "packet size too large: %s", optarg);
243 			break;
244 		case 't':
245 			ttl = atoi(optarg);
246 			if (ttl <= 0)
247 				errx(1, "bad ttl value: %s", optarg);
248 			if (ttl > 255)
249 				errx(1, "ttl value too large: %s", optarg);
250 			break;
251 		case 'v':
252 			options |= F_VERBOSE;
253 			break;
254 		default:
255 			usage();
256 		}
257 	argc -= optind;
258 	argv += optind;
259 
260 	if (argc != 1)
261 		usage();
262 	target = *argv;
263 
264 	memset(&whereto, 0, sizeof(struct sockaddr));
265 	to = (struct sockaddr_in *)&whereto;
266 	to->sin_family = AF_INET;
267 	to->sin_addr.s_addr = inet_addr(target);
268 	if (to->sin_addr.s_addr != (u_int)-1)
269 		hostname = target;
270 	else {
271 		hp = gethostbyname(target);
272 		if (!hp)
273 			errx(1, "unknown host: %s", target);
274 		to->sin_family = hp->h_addrtype;
275 		memcpy(&to->sin_addr, hp->h_addr, hp->h_length);
276 		(void)strncpy(hnamebuf, hp->h_name, sizeof(hnamebuf) - 1);
277 		hostname = hnamebuf;
278 	}
279 
280 	if (options & F_FLOOD && options & F_INTERVAL)
281 		errx(1, "-f and -i options are incompatible");
282 
283 	if (datalen >= sizeof(struct timeval))	/* can we time transfer */
284 		timing = 1;
285 	packlen = datalen + MAXIPLEN + MAXICMPLEN;
286 	if (!(packet = (u_char *)malloc((u_int)packlen)))
287 		err(1, "malloc");
288 	if (!(options & F_PINGFILLED))
289 		for (i = 8; i < datalen; ++i)
290 			*datap++ = i;
291 
292 	ident = getpid() & 0xFFFF;
293 
294 	if (!(proto = getprotobyname("icmp")))
295 		errx(1, "unknown protocol icmp");
296 	if ((s = socket(AF_INET, SOCK_RAW, proto->p_proto)) < 0)
297 		err(1, "socket");
298 	hold = 1;
299 	if (options & F_SO_DEBUG)
300 		(void)setsockopt(s, SOL_SOCKET, SO_DEBUG, (char *)&hold,
301 		    sizeof(hold));
302 	if (options & F_SO_DONTROUTE)
303 		(void)setsockopt(s, SOL_SOCKET, SO_DONTROUTE, (char *)&hold,
304 		    sizeof(hold));
305 
306 	/* record route option */
307 	if (options & F_RROUTE) {
308 #ifdef IP_OPTIONS
309 		rspace[IPOPT_OPTVAL] = IPOPT_RR;
310 		rspace[IPOPT_OLEN] = sizeof(rspace)-1;
311 		rspace[IPOPT_OFFSET] = IPOPT_MINOFF;
312 		if (setsockopt(s, IPPROTO_IP, IP_OPTIONS, rspace,
313 		    sizeof(rspace)) < 0) {
314 			perror("ping: record route");
315 			exit(1);
316 		}
317 #else
318 		errx(1, "record route not available in this implementation");
319 #endif /* IP_OPTIONS */
320 	}
321 
322 	if ((moptions & MULTICAST_NOLOOP) &&
323 	    setsockopt(s, IPPROTO_IP, IP_MULTICAST_LOOP, &loop,
324 		       sizeof(loop)) < 0)
325 		err(1, "setsockopt IP_MULTICAST_LOOP");
326 	if ((moptions & MULTICAST_TTL) &&
327 	    setsockopt(s, IPPROTO_IP, IP_MULTICAST_TTL, &ttl,
328 		       sizeof(ttl)) < 0)
329 		err(1, "setsockopt IP_MULTICAST_TTL");
330 	if ((moptions & MULTICAST_IF) &&
331 	    setsockopt(s, IPPROTO_IP, IP_MULTICAST_IF, &ifaddr,
332 		       sizeof(ifaddr)) < 0)
333 		err(1, "setsockopt IP_MULTICAST_IF");
334 
335 	/*
336 	 * When pinging the broadcast address, you can get a lot of answers.
337 	 * Doing something so evil is useful if you are trying to stress the
338 	 * ethernet, or just want to fill the arp cache to get some stuff for
339 	 * /etc/ethers.
340 	 */
341 	hold = 48 * 1024;
342 	(void)setsockopt(s, SOL_SOCKET, SO_RCVBUF, (char *)&hold,
343 	    sizeof(hold));
344 
345 	if (to->sin_family == AF_INET)
346 		(void)printf("PING %s (%s): %d data bytes\n", hostname,
347 		    inet_ntoa(*(struct in_addr *)&to->sin_addr.s_addr),
348 		    datalen);
349 	else
350 		(void)printf("PING %s: %d data bytes\n", hostname, datalen);
351 
352 	(void)signal(SIGINT, finish);
353 	(void)signal(SIGALRM, catcher);
354 
355 	while (preload--)		/* fire off them quickies */
356 		pinger();
357 
358 	if ((options & F_FLOOD) == 0)
359 		catcher();		/* start things going */
360 
361 	for (;;) {
362 		struct sockaddr_in from;
363 		register int cc;
364 		int fromlen;
365 
366 		if (options & F_FLOOD) {
367 			pinger();
368 			timeout.tv_sec = 0;
369 			timeout.tv_usec = 10000;
370 			fdmask = 1 << s;
371 			if (select(s + 1, (fd_set *)&fdmask, (fd_set *)NULL,
372 			    (fd_set *)NULL, &timeout) < 1)
373 				continue;
374 		}
375 		fromlen = sizeof(from);
376 		if ((cc = recvfrom(s, (char *)packet, packlen, 0,
377 		    (struct sockaddr *)&from, &fromlen)) < 0) {
378 			if (errno == EINTR)
379 				continue;
380 			perror("ping: recvfrom");
381 			continue;
382 		}
383 		pr_pack((char *)packet, cc, &from);
384 		if (npackets && nreceived >= npackets)
385 			break;
386 	}
387 	finish();
388 	/* NOTREACHED */
389 	exit(0);	/* Make the compiler happy */
390 }
391 
392 /*
393  * catcher --
394  *	This routine causes another PING to be transmitted, and then
395  * schedules another SIGALRM for 1 second from now.
396  *
397  * bug --
398  *	Our sense of time will slowly skew (i.e., packets will not be
399  * launched exactly at 1-second intervals).  This does not affect the
400  * quality of the delay and loss statistics.
401  */
402 void
403 catcher()
404 {
405 	int waittime;
406 
407 	pinger();
408 	(void)signal(SIGALRM, catcher);
409 	if (!npackets || ntransmitted < npackets)
410 		alarm((u_int)interval);
411 	else {
412 		if (nreceived) {
413 			waittime = 2 * tmax / 1000;
414 			if (!waittime)
415 				waittime = 1;
416 		} else
417 			waittime = MAXWAIT;
418 		(void)signal(SIGALRM, finish);
419 		(void)alarm((u_int)waittime);
420 	}
421 }
422 
423 /*
424  * pinger --
425  *	Compose and transmit an ICMP ECHO REQUEST packet.  The IP packet
426  * will be added on by the kernel.  The ID field is our UNIX process ID,
427  * and the sequence number is an ascending integer.  The first 8 bytes
428  * of the data portion are used to hold a UNIX "timeval" struct in VAX
429  * byte-order, to compute the round-trip time.
430  */
431 void
432 pinger()
433 {
434 	register struct icmp *icp;
435 	register int cc;
436 	int i;
437 
438 	icp = (struct icmp *)outpack;
439 	icp->icmp_type = ICMP_ECHO;
440 	icp->icmp_code = 0;
441 	icp->icmp_cksum = 0;
442 	icp->icmp_seq = ntransmitted++;
443 	icp->icmp_id = ident;			/* ID */
444 
445 	CLR(icp->icmp_seq % mx_dup_ck);
446 
447 	if (timing)
448 		(void)gettimeofday((struct timeval *)&outpack[8],
449 		    (struct timezone *)NULL);
450 
451 	cc = datalen + 8;			/* skips ICMP portion */
452 
453 	/* compute ICMP checksum here */
454 	icp->icmp_cksum = in_cksum((u_short *)icp, cc);
455 
456 	i = sendto(s, (char *)outpack, cc, 0, &whereto,
457 	    sizeof(struct sockaddr));
458 
459 	if (i < 0 || i != cc)  {
460 		if (i < 0)
461 			perror("ping: sendto");
462 		(void)printf("ping: wrote %s %d chars, ret=%d\n",
463 		    hostname, cc, i);
464 	}
465 	if (!(options & F_QUIET) && options & F_FLOOD)
466 		(void)write(STDOUT_FILENO, &DOT, 1);
467 }
468 
469 /*
470  * pr_pack --
471  *	Print out the packet, if it came from us.  This logic is necessary
472  * because ALL readers of the ICMP socket get a copy of ALL ICMP packets
473  * which arrive ('tis only fair).  This permits multiple copies of this
474  * program to be run without having intermingled output (or statistics!).
475  */
476 void
477 pr_pack(buf, cc, from)
478 	char *buf;
479 	int cc;
480 	struct sockaddr_in *from;
481 {
482 	register struct icmp *icp;
483 	register u_long l;
484 	register int i, j;
485 	register u_char *cp,*dp;
486 	static int old_rrlen;
487 	static char old_rr[MAX_IPOPTLEN];
488 	struct ip *ip;
489 	struct timeval tv, *tp;
490 	double triptime;
491 	int hlen, dupflag;
492 
493 	(void)gettimeofday(&tv, (struct timezone *)NULL);
494 
495 	/* Check the IP header */
496 	ip = (struct ip *)buf;
497 	hlen = ip->ip_hl << 2;
498 	if (cc < hlen + ICMP_MINLEN) {
499 		if (options & F_VERBOSE)
500 			warnx("packet too short (%d bytes) from %s", cc,
501 			  inet_ntoa(*(struct in_addr *)&from->sin_addr.s_addr));
502 		return;
503 	}
504 
505 	/* Now the ICMP part */
506 	cc -= hlen;
507 	icp = (struct icmp *)(buf + hlen);
508 	if (icp->icmp_type == ICMP_ECHOREPLY) {
509 		if (icp->icmp_id != ident)
510 			return;			/* 'Twas not our ECHO */
511 		++nreceived;
512 		if (timing) {
513 #ifndef icmp_data
514 			tp = (struct timeval *)&icp->icmp_ip;
515 #else
516 			tp = (struct timeval *)icp->icmp_data;
517 #endif
518 			tvsub(&tv, tp);
519 			triptime = ((double)tv.tv_sec) * 1000.0 +
520 			    ((double)tv.tv_usec) / 1000.0;
521 			tsum += triptime;
522 			if (triptime < tmin)
523 				tmin = triptime;
524 			if (triptime > tmax)
525 				tmax = triptime;
526 		}
527 
528 		if (TST(icp->icmp_seq % mx_dup_ck)) {
529 			++nrepeats;
530 			--nreceived;
531 			dupflag = 1;
532 		} else {
533 			SET(icp->icmp_seq % mx_dup_ck);
534 			dupflag = 0;
535 		}
536 
537 		if (options & F_QUIET)
538 			return;
539 
540 		if (options & F_FLOOD)
541 			(void)write(STDOUT_FILENO, &BSPACE, 1);
542 		else {
543 			(void)printf("%d bytes from %s: icmp_seq=%u", cc,
544 			   inet_ntoa(*(struct in_addr *)&from->sin_addr.s_addr),
545 			   icp->icmp_seq);
546 			(void)printf(" ttl=%d", ip->ip_ttl);
547 			if (timing)
548 				(void)printf(" time=%.3f ms", triptime);
549 			if (dupflag)
550 				(void)printf(" (DUP!)");
551 			/* check the data */
552 			cp = (u_char*)&icp->icmp_data[8];
553 			dp = &outpack[8 + sizeof(struct timeval)];
554 			for (i = 8; i < datalen; ++i, ++cp, ++dp) {
555 				if (*cp != *dp) {
556 	(void)printf("\nwrong data byte #%d should be 0x%x but was 0x%x",
557 	    i, *dp, *cp);
558 					cp = (u_char*)&icp->icmp_data[0];
559 					for (i = 8; i < datalen; ++i, ++cp) {
560 						if ((i % 32) == 8)
561 							(void)printf("\n\t");
562 						(void)printf("%x ", *cp);
563 					}
564 					break;
565 				}
566 			}
567 		}
568 	} else {
569 		/* We've got something other than an ECHOREPLY */
570 		if (!(options & F_VERBOSE))
571 			return;
572 		(void)printf("%d bytes from %s: ", cc,
573 		    pr_addr(from->sin_addr.s_addr));
574 		pr_icmph(icp);
575 	}
576 
577 	/* Display any IP options */
578 	cp = (u_char *)buf + sizeof(struct ip);
579 
580 	for (; hlen > (int)sizeof(struct ip); --hlen, ++cp)
581 		switch (*cp) {
582 		case IPOPT_EOL:
583 			hlen = 0;
584 			break;
585 		case IPOPT_LSRR:
586 			(void)printf("\nLSRR: ");
587 			hlen -= 2;
588 			j = *++cp;
589 			++cp;
590 			if (j > IPOPT_MINOFF)
591 				for (;;) {
592 					l = *++cp;
593 					l = (l<<8) + *++cp;
594 					l = (l<<8) + *++cp;
595 					l = (l<<8) + *++cp;
596 					if (l == 0)
597 						(void)printf("\t0.0.0.0");
598 				else
599 					(void)printf("\t%s", pr_addr(ntohl(l)));
600 				hlen -= 4;
601 				j -= 4;
602 				if (j <= IPOPT_MINOFF)
603 					break;
604 				(void)putchar('\n');
605 			}
606 			break;
607 		case IPOPT_RR:
608 			j = *++cp;		/* get length */
609 			i = *++cp;		/* and pointer */
610 			hlen -= 2;
611 			if (i > j)
612 				i = j;
613 			i -= IPOPT_MINOFF;
614 			if (i <= 0)
615 				continue;
616 			if (i == old_rrlen
617 			    && cp == (u_char *)buf + sizeof(struct ip) + 2
618 			    && !memcmp(cp, old_rr, i)
619 			    && !(options & F_FLOOD)) {
620 				(void)printf("\t(same route)");
621 				i = ((i + 3) / 4) * 4;
622 				hlen -= i;
623 				cp += i;
624 				break;
625 			}
626 			old_rrlen = i;
627 			memcpy(old_rr, cp, i);
628 			(void)printf("\nRR: ");
629 			for (;;) {
630 				l = *++cp;
631 				l = (l<<8) + *++cp;
632 				l = (l<<8) + *++cp;
633 				l = (l<<8) + *++cp;
634 				if (l == 0)
635 					(void)printf("\t0.0.0.0");
636 				else
637 					(void)printf("\t%s", pr_addr(ntohl(l)));
638 				hlen -= 4;
639 				i -= 4;
640 				if (i <= 0)
641 					break;
642 				(void)putchar('\n');
643 			}
644 			break;
645 		case IPOPT_NOP:
646 			(void)printf("\nNOP");
647 			break;
648 		default:
649 			(void)printf("\nunknown option %x", *cp);
650 			break;
651 		}
652 	if (!(options & F_FLOOD)) {
653 		(void)putchar('\n');
654 		(void)fflush(stdout);
655 	}
656 }
657 
658 /*
659  * in_cksum --
660  *	Checksum routine for Internet Protocol family headers (C Version)
661  */
662 int
663 in_cksum(addr, len)
664 	u_short *addr;
665 	int len;
666 {
667 	register int nleft = len;
668 	register u_short *w = addr;
669 	register int sum = 0;
670 	u_short answer = 0;
671 
672 	/*
673 	 * Our algorithm is simple, using a 32 bit accumulator (sum), we add
674 	 * sequential 16 bit words to it, and at the end, fold back all the
675 	 * carry bits from the top 16 bits into the lower 16 bits.
676 	 */
677 	while (nleft > 1)  {
678 		sum += *w++;
679 		nleft -= 2;
680 	}
681 
682 	/* mop up an odd byte, if necessary */
683 	if (nleft == 1) {
684 		*(u_char *)(&answer) = *(u_char *)w ;
685 		sum += answer;
686 	}
687 
688 	/* add back carry outs from top 16 bits to low 16 bits */
689 	sum = (sum >> 16) + (sum & 0xffff);	/* add hi 16 to low 16 */
690 	sum += (sum >> 16);			/* add carry */
691 	answer = ~sum;				/* truncate to 16 bits */
692 	return(answer);
693 }
694 
695 /*
696  * tvsub --
697  *	Subtract 2 timeval structs:  out = out - in.  Out is assumed to
698  * be >= in.
699  */
700 void
701 tvsub(out, in)
702 	register struct timeval *out, *in;
703 {
704 	if ((out->tv_usec -= in->tv_usec) < 0) {
705 		--out->tv_sec;
706 		out->tv_usec += 1000000;
707 	}
708 	out->tv_sec -= in->tv_sec;
709 }
710 
711 /*
712  * finish --
713  *	Print out statistics, and give up.
714  */
715 void
716 finish()
717 {
718 	register int i;
719 
720 	(void)signal(SIGINT, SIG_IGN);
721 	(void)putchar('\n');
722 	(void)fflush(stdout);
723 	(void)printf("--- %s ping statistics ---\n", hostname);
724 	(void)printf("%ld packets transmitted, ", ntransmitted);
725 	(void)printf("%ld packets received, ", nreceived);
726 	if (nrepeats)
727 		(void)printf("+%ld duplicates, ", nrepeats);
728 	if (ntransmitted)
729 		if (nreceived > ntransmitted)
730 			(void)printf("-- somebody's printing up packets!");
731 		else
732 			(void)printf("%d%% packet loss",
733 			    (int) (((ntransmitted - nreceived) * 100) /
734 			    ntransmitted));
735 	(void)putchar('\n');
736 	if (nreceived && timing) {
737 		/* Only display average to microseconds */
738 		i = 1000.0 * tsum / (nreceived + nrepeats);
739 		(void)printf("round-trip min/avg/max = %.3f/%.3f/%.3f ms\n",
740 		    tmin, ((double)i) / 1000.0, tmax);
741 	}
742 	exit(0);
743 }
744 
745 #ifdef notdef
746 static char *ttab[] = {
747 	"Echo Reply",		/* ip + seq + udata */
748 	"Dest Unreachable",	/* net, host, proto, port, frag, sr + IP */
749 	"Source Quench",	/* IP */
750 	"Redirect",		/* redirect type, gateway, + IP  */
751 	"Echo",
752 	"Time Exceeded",	/* transit, frag reassem + IP */
753 	"Parameter Problem",	/* pointer + IP */
754 	"Timestamp",		/* id + seq + three timestamps */
755 	"Timestamp Reply",	/* " */
756 	"Info Request",		/* id + sq */
757 	"Info Reply"		/* " */
758 };
759 #endif
760 
761 /*
762  * pr_icmph --
763  *	Print a descriptive string about an ICMP header.
764  */
765 void
766 pr_icmph(icp)
767 	struct icmp *icp;
768 {
769 	switch(icp->icmp_type) {
770 	case ICMP_ECHOREPLY:
771 		(void)printf("Echo Reply\n");
772 		/* XXX ID + Seq + Data */
773 		break;
774 	case ICMP_UNREACH:
775 		switch(icp->icmp_code) {
776 		case ICMP_UNREACH_NET:
777 			(void)printf("Destination Net Unreachable\n");
778 			break;
779 		case ICMP_UNREACH_HOST:
780 			(void)printf("Destination Host Unreachable\n");
781 			break;
782 		case ICMP_UNREACH_PROTOCOL:
783 			(void)printf("Destination Protocol Unreachable\n");
784 			break;
785 		case ICMP_UNREACH_PORT:
786 			(void)printf("Destination Port Unreachable\n");
787 			break;
788 		case ICMP_UNREACH_NEEDFRAG:
789 			(void)printf("frag needed and DF set\n");
790 			break;
791 		case ICMP_UNREACH_SRCFAIL:
792 			(void)printf("Source Route Failed\n");
793 			break;
794 		default:
795 			(void)printf("Dest Unreachable, Bad Code: %d\n",
796 			    icp->icmp_code);
797 			break;
798 		}
799 		/* Print returned IP header information */
800 #ifndef icmp_data
801 		pr_retip(&icp->icmp_ip);
802 #else
803 		pr_retip((struct ip *)icp->icmp_data);
804 #endif
805 		break;
806 	case ICMP_SOURCEQUENCH:
807 		(void)printf("Source Quench\n");
808 #ifndef icmp_data
809 		pr_retip(&icp->icmp_ip);
810 #else
811 		pr_retip((struct ip *)icp->icmp_data);
812 #endif
813 		break;
814 	case ICMP_REDIRECT:
815 		switch(icp->icmp_code) {
816 		case ICMP_REDIRECT_NET:
817 			(void)printf("Redirect Network");
818 			break;
819 		case ICMP_REDIRECT_HOST:
820 			(void)printf("Redirect Host");
821 			break;
822 		case ICMP_REDIRECT_TOSNET:
823 			(void)printf("Redirect Type of Service and Network");
824 			break;
825 		case ICMP_REDIRECT_TOSHOST:
826 			(void)printf("Redirect Type of Service and Host");
827 			break;
828 		default:
829 			(void)printf("Redirect, Bad Code: %d", icp->icmp_code);
830 			break;
831 		}
832 		(void)printf("(New addr: 0x%08lx)\n", icp->icmp_gwaddr.s_addr);
833 #ifndef icmp_data
834 		pr_retip(&icp->icmp_ip);
835 #else
836 		pr_retip((struct ip *)icp->icmp_data);
837 #endif
838 		break;
839 	case ICMP_ECHO:
840 		(void)printf("Echo Request\n");
841 		/* XXX ID + Seq + Data */
842 		break;
843 	case ICMP_TIMXCEED:
844 		switch(icp->icmp_code) {
845 		case ICMP_TIMXCEED_INTRANS:
846 			(void)printf("Time to live exceeded\n");
847 			break;
848 		case ICMP_TIMXCEED_REASS:
849 			(void)printf("Frag reassembly time exceeded\n");
850 			break;
851 		default:
852 			(void)printf("Time exceeded, Bad Code: %d\n",
853 			    icp->icmp_code);
854 			break;
855 		}
856 #ifndef icmp_data
857 		pr_retip(&icp->icmp_ip);
858 #else
859 		pr_retip((struct ip *)icp->icmp_data);
860 #endif
861 		break;
862 	case ICMP_PARAMPROB:
863 		(void)printf("Parameter problem: pointer = 0x%02x\n",
864 		    icp->icmp_hun.ih_pptr);
865 #ifndef icmp_data
866 		pr_retip(&icp->icmp_ip);
867 #else
868 		pr_retip((struct ip *)icp->icmp_data);
869 #endif
870 		break;
871 	case ICMP_TSTAMP:
872 		(void)printf("Timestamp\n");
873 		/* XXX ID + Seq + 3 timestamps */
874 		break;
875 	case ICMP_TSTAMPREPLY:
876 		(void)printf("Timestamp Reply\n");
877 		/* XXX ID + Seq + 3 timestamps */
878 		break;
879 	case ICMP_IREQ:
880 		(void)printf("Information Request\n");
881 		/* XXX ID + Seq */
882 		break;
883 	case ICMP_IREQREPLY:
884 		(void)printf("Information Reply\n");
885 		/* XXX ID + Seq */
886 		break;
887 #ifdef ICMP_MASKREQ
888 	case ICMP_MASKREQ:
889 		(void)printf("Address Mask Request\n");
890 		break;
891 #endif
892 #ifdef ICMP_MASKREPLY
893 	case ICMP_MASKREPLY:
894 		(void)printf("Address Mask Reply\n");
895 		break;
896 #endif
897 	default:
898 		(void)printf("Bad ICMP type: %d\n", icp->icmp_type);
899 	}
900 }
901 
902 /*
903  * pr_iph --
904  *	Print an IP header with options.
905  */
906 void
907 pr_iph(ip)
908 	struct ip *ip;
909 {
910 	int hlen;
911 	u_char *cp;
912 
913 	hlen = ip->ip_hl << 2;
914 	cp = (u_char *)ip + 20;		/* point to options */
915 
916 	(void)printf("Vr HL TOS  Len   ID Flg  off TTL Pro  cks      Src      Dst Data\n");
917 	(void)printf(" %1x  %1x  %02x %04x %04x",
918 	    ip->ip_v, ip->ip_hl, ip->ip_tos, ip->ip_len, ip->ip_id);
919 	(void)printf("   %1x %04x", ((ip->ip_off) & 0xe000) >> 13,
920 	    (ip->ip_off) & 0x1fff);
921 	(void)printf("  %02x  %02x %04x", ip->ip_ttl, ip->ip_p, ip->ip_sum);
922 	(void)printf(" %s ", inet_ntoa(*(struct in_addr *)&ip->ip_src.s_addr));
923 	(void)printf(" %s ", inet_ntoa(*(struct in_addr *)&ip->ip_dst.s_addr));
924 	/* dump and option bytes */
925 	while (hlen-- > 20) {
926 		(void)printf("%02x", *cp++);
927 	}
928 	(void)putchar('\n');
929 }
930 
931 /*
932  * pr_addr --
933  *	Return an ascii host address as a dotted quad and optionally with
934  * a hostname.
935  */
936 char *
937 pr_addr(l)
938 	u_long l;
939 {
940 	struct hostent *hp;
941 	static char buf[80];
942 
943 	if ((options & F_NUMERIC) ||
944 	    !(hp = gethostbyaddr((char *)&l, 4, AF_INET)))
945 		(void)sprintf(buf, "%s", inet_ntoa(*(struct in_addr *)&l));
946 	else
947 		(void)sprintf(buf, "%s (%s)", hp->h_name,
948 		    inet_ntoa(*(struct in_addr *)&l));
949 	return(buf);
950 }
951 
952 /*
953  * pr_retip --
954  *	Dump some info on a returned (via ICMP) IP packet.
955  */
956 void
957 pr_retip(ip)
958 	struct ip *ip;
959 {
960 	int hlen;
961 	u_char *cp;
962 
963 	pr_iph(ip);
964 	hlen = ip->ip_hl << 2;
965 	cp = (u_char *)ip + hlen;
966 
967 	if (ip->ip_p == 6)
968 		(void)printf("TCP: from port %u, to port %u (decimal)\n",
969 		    (*cp * 256 + *(cp + 1)), (*(cp + 2) * 256 + *(cp + 3)));
970 	else if (ip->ip_p == 17)
971 		(void)printf("UDP: from port %u, to port %u (decimal)\n",
972 			(*cp * 256 + *(cp + 1)), (*(cp + 2) * 256 + *(cp + 3)));
973 }
974 
975 void
976 fill(bp, patp)
977 	char *bp, *patp;
978 {
979 	register int ii, jj, kk;
980 	int pat[16];
981 	char *cp;
982 
983 	for (cp = patp; *cp; cp++)
984 		if (!isxdigit(*cp))
985 			errx(1, "patterns must be specified as hex digits");
986 	ii = sscanf(patp,
987 	    "%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x",
988 	    &pat[0], &pat[1], &pat[2], &pat[3], &pat[4], &pat[5], &pat[6],
989 	    &pat[7], &pat[8], &pat[9], &pat[10], &pat[11], &pat[12],
990 	    &pat[13], &pat[14], &pat[15]);
991 
992 	if (ii > 0)
993 		for (kk = 0;
994 		    kk <= MAXPACKET - (8 + sizeof(struct timeval) + ii);
995 		    kk += ii)
996 			for (jj = 0; jj < ii; ++jj)
997 				bp[jj + kk] = pat[jj];
998 	if (!(options & F_QUIET)) {
999 		(void)printf("PATTERN: 0x");
1000 		for (jj = 0; jj < ii; ++jj)
1001 			(void)printf("%02x", bp[jj] & 0xFF);
1002 		(void)printf("\n");
1003 	}
1004 }
1005 
1006 void
1007 usage()
1008 {
1009 	(void)fprintf(stderr,
1010 	    "usage: ping [-dfLnqRrv] [-c count] [-I ifaddr] [-i wait] [-l preload]\n\t[-p pattern] [-s packetsize] [-t ttl] host\n");
1011 	exit(1);
1012 }
1013