xref: /netbsd-src/sbin/ping/ping.c (revision fdecd6a253f999ae92b139670d9e15cc9df4497c)
1 /*	$NetBSD: ping.c,v 1.30 1997/06/01 19:34:49 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1989, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Mike Muuss.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the University of
21  *	California, Berkeley and its contributors.
22  * 4. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  */
38 /*
39  *			P I N G . C
40  *
41  * Using the InterNet Control Message Protocol (ICMP) "ECHO" facility,
42  * measure round-trip-delays and packet loss across network paths.
43  *
44  * Author -
45  *	Mike Muuss
46  *	U. S. Army Ballistic Research Laboratory
47  *	December, 1983
48  * Modified at Uc Berkeley
49  * Record Route and verbose headers - Phil Dykstra, BRL, March 1988.
50  * Multicast options (ttl, if, loop) - Steve Deering, Stanford, August 1988.
51  * ttl, duplicate detection - Cliff Frost, UCB, April 1989
52  * Pad pattern - Cliff Frost (from Tom Ferrin, UCSF), April 1989
53  *
54  * Status -
55  *	Public Domain.  Distribution Unlimited.
56  *
57  * Bugs -
58  *	More statistics could always be gathered.
59  *	This program has to run SUID to ROOT to access the ICMP socket.
60  */
61 
62 #ifndef lint
63 static char rcsid[] = "$NetBSD: ping.c,v 1.30 1997/06/01 19:34:49 christos Exp $";
64 #endif
65 
66 #include <stdio.h>
67 #include <errno.h>
68 #include <sys/time.h>
69 #include <sys/types.h>
70 #include <sys/signal.h>
71 #include <sys/param.h>
72 #include <sys/socket.h>
73 #include <sys/file.h>
74 #include <termios.h>
75 #include <stdlib.h>
76 #include <unistd.h>
77 #include <limits.h>
78 #include <string.h>
79 #include <err.h>
80 #ifdef sgi
81 #include <bstring.h>
82 #include <getopt.h>
83 #include <sys/prctl.h>
84 #include <sys/schedctl.h>
85 #endif
86 
87 #include <netinet/in_systm.h>
88 #include <netinet/in.h>
89 #include <netinet/ip.h>
90 #include <netinet/ip_icmp.h>
91 #include <netinet/ip_var.h>
92 #include <arpa/inet.h>
93 #include <ctype.h>
94 #include <netdb.h>
95 
96 #define FLOOD_INTVL	0.01		/* default flood output interval */
97 #define	MAXPACKET	(65536-60-8)	/* max packet size */
98 
99 #define F_VERBOSE	0x0001
100 #define F_QUIET		0x0002		/* minimize all output */
101 #define F_SEMI_QUIET	0x0004		/* ignore our ICMP errors */
102 #define F_FLOOD		0x0008		/* flood-ping */
103 #define	F_RECORD_ROUTE	0x0010		/* record route */
104 #define F_SOURCE_ROUTE	0x0020		/* loose source route */
105 #define F_PING_FILLED	0x0040		/* is buffer filled with user data? */
106 #define F_PING_RANDOM	0x0080		/* use random data */
107 #define	F_NUMERIC	0x0100		/* do not do gethostbyaddr() calls */
108 #define F_TIMING	0x0200		/* room for a timestamp */
109 #define F_DF		0x0400		/* set IP DF bit */
110 #define F_SOURCE_ADDR	0x0800		/* set source IP address/interface */
111 #define F_ONCE		0x1000		/* exit(0) after receiving 1 reply */
112 #define F_MCAST		0x2000		/* multicast target */
113 #define F_MCAST_NOLOOP	0x4000		/* no multicast loopback */
114 
115 /* MAX_DUP_CHK is the number of bits in received table, the
116  *	maximum number of received sequence numbers we can track to check
117  *	for duplicates.
118  */
119 #define MAX_DUP_CHK     (8 * 2048)
120 u_char	rcvd_tbl[MAX_DUP_CHK/8];
121 int     nrepeats = 0;
122 #define A(seq)	rcvd_tbl[(seq/8)%sizeof(rcvd_tbl)]  /* byte in array */
123 #define B(seq)	(1 << (seq & 0x07))	/* bit in byte */
124 #define SET(seq) (A(seq) |= B(seq))
125 #define CLR(seq) (A(seq) &= (~B(seq)))
126 #define TST(seq) (A(seq) & B(seq))
127 
128 
129 
130 u_char	*packet;
131 int	packlen;
132 int	pingflags = 0, options;
133 char	*fill_pat;
134 
135 int s;					/* Socket file descriptor */
136 
137 #define PHDR_LEN sizeof(struct timeval)	/* size of timestamp header */
138 struct sockaddr_in whereto, send_addr;	/* Who to ping */
139 struct sockaddr_in src_addr;		/* from where */
140 struct sockaddr_in loc_addr;		/* 127.1 */
141 int datalen = 64-PHDR_LEN;		/* How much data */
142 
143 #ifdef sgi
144 static char *__progname;
145 #else
146 extern char *__progname;
147 #endif
148 
149 
150 char hostname[MAXHOSTNAMELEN];
151 
152 static struct {
153 	struct ip	o_ip;
154 	char		o_opt[MAX_IPOPTLEN];
155 	union {
156 		u_char	    u_buf[MAXPACKET];
157 		struct icmp u_icmp;
158 	} o_u;
159 } out_pack;
160 #define	opack_icmp	out_pack.o_u.u_icmp
161 struct ip *opack_ip;
162 
163 char optspace[MAX_IPOPTLEN];		/* record route space */
164 int optlen;
165 
166 
167 int npackets;				/* total packets to send */
168 int preload;				/* number of packets to "preload" */
169 int ntransmitted;			/* output sequence # = #sent */
170 int ident;
171 
172 int nreceived;				/* # of packets we got back */
173 
174 double interval;			/* interval between packets */
175 struct timeval interval_tv;
176 double tmin = 999999999;
177 double tmax = 0;
178 double tsum = 0;			/* sum of all times */
179 double maxwait = 0;
180 
181 #ifdef SIGINFO
182 int reset_kerninfo;
183 #endif
184 
185 int bufspace = 60*1024;
186 
187 struct timeval now, clear_cache, last_tx, next_tx, first_tx;
188 struct timeval last_rx, first_rx;
189 int lastrcvd = 1;			/* last ping sent has been received */
190 
191 static struct timeval jiggle_time;
192 static int jiggle_cnt, total_jiggled, jiggle_direction = -1;
193 
194 static void doit(void);
195 static void prefinish(int);
196 static void prtsig(int);
197 static void finish(int);
198 static void summary(int);
199 static void pinger(void);
200 static void fill(void);
201 static void rnd_fill(void);
202 static double diffsec(struct timeval *, struct timeval *);
203 static void timevaladd(struct timeval *, struct timeval *);
204 static void sec_to_timeval(const double, struct timeval *);
205 static double timeval_to_sec(const struct timeval *);
206 static void pr_pack(u_char *, int, struct sockaddr_in *);
207 static u_short in_cksum(u_short *, u_int);
208 static void pr_saddr(char *, u_char *);
209 static char *pr_addr(struct in_addr *);
210 static void pr_iph(struct icmp *, int);
211 static void pr_retip(struct icmp *, int);
212 static int pr_icmph(struct icmp *, struct sockaddr_in *, int);
213 static void jiggle(int), jiggle_flush(int);
214 static void gethost(const char *, const char *,
215 		    struct sockaddr_in *, char *, int);
216 static void usage(void);
217 
218 
219 int
220 main(int argc, char *argv[])
221 {
222 	int c, i, on = 1, hostind = 0;
223 	long l;
224 	u_char ttl = 0;
225 	u_long tos = 0;
226 	char *p;
227 #ifdef SIGINFO
228 	struct termios ts;
229 #endif
230 
231 
232 #if defined(SIGINFO) && defined(NOKERNINFO)
233 	if (tcgetattr (0, &ts) != -1) {
234 		reset_kerninfo = !(ts.c_lflag & NOKERNINFO);
235 		ts.c_lflag |= NOKERNINFO;
236 		tcsetattr (0, TCSANOW, &ts);
237 	}
238 #endif
239 	while ((c = getopt(argc, argv,
240 			   "c:dDfg:h:i:I:l:Lnop:PqQrRs:t:T:vw:")) != -1) {
241 		switch (c) {
242 		case 'c':
243 			npackets = strtol(optarg, &p, 0);
244 			if (*p != '\0' || npackets <= 0)
245 				errx(1, "Bad/invalid number of packets");
246 			break;
247 		case 'D':
248 			pingflags |= F_DF;
249 			break;
250 		case 'd':
251 			options |= SO_DEBUG;
252 			break;
253 		case 'f':
254 			pingflags |= F_FLOOD;
255 			break;
256 		case 'h':
257 			hostind = optind-1;
258 			break;
259 		case 'i':		/* wait between sending packets */
260 			interval = strtod(optarg, &p);
261 			if (*p != '\0' || interval <= 0)
262 				errx(1, "Bad/invalid interval %s", optarg);
263 			break;
264 		case 'l':
265 			preload = strtol(optarg, &p, 0);
266 			if (*p != '\0' || preload < 0)
267 				errx(1, "Bad/invalid preload value %s",
268 				     optarg);
269 			break;
270 		case 'n':
271 			pingflags |= F_NUMERIC;
272 			break;
273 		case 'o':
274 			pingflags |= F_ONCE;
275 			break;
276 		case 'p':		/* fill buffer with user pattern */
277 			if (pingflags & F_PING_RANDOM)
278 				errx(1, "Only one of -P and -p allowed");
279 			pingflags |= F_PING_FILLED;
280 			fill_pat = optarg;
281 			break;
282 		case 'P':
283 			if (pingflags & F_PING_FILLED)
284 				errx(1, "Only one of -P and -p allowed");
285 			pingflags |= F_PING_RANDOM;
286 			break;
287 		case 'q':
288 			pingflags |= F_QUIET;
289 			break;
290 		case 'Q':
291 			pingflags |= F_SEMI_QUIET;
292 			break;
293 		case 'r':
294 			options |= SO_DONTROUTE;
295 			break;
296 		case 's':		/* size of packet to send */
297 			datalen = strtol(optarg, &p, 0);
298 			if (*p != '\0' || datalen <= 0)
299 				errx(1, "Bad/invalid packet size %s", optarg);
300 			if (datalen > MAXPACKET)
301 				errx(1, "packet size is too large");
302 			break;
303 		case 'v':
304 			pingflags |= F_VERBOSE;
305 			break;
306 		case 'R':
307 			pingflags |= F_RECORD_ROUTE;
308 			break;
309 		case 'L':
310 			pingflags |= F_MCAST_NOLOOP;
311 			break;
312 		case 't':
313 			tos = strtoul(optarg, &p, 0);
314 			if (*p != '\0' ||  tos > 0xFF)
315 				errx(1, "bad tos value: %s", optarg);
316 			break;
317 		case 'T':
318 			l = strtol(optarg, &p, 0);
319 			if (*p != '\0' || l > 255 || l <= 0)
320 				errx(1, "ttl out of range");
321 			ttl = (u_char)l;    /* cannot check >255 otherwise */
322 			break;
323 		case 'I':
324 			pingflags |= F_SOURCE_ADDR;
325 			gethost("-I", optarg, &src_addr, 0, 0);
326 			break;
327 		case 'g':
328 			pingflags |= F_SOURCE_ROUTE;
329 			gethost("-g", optarg, &send_addr, 0, 0);
330 			break;
331 		case 'w':
332 			maxwait = strtod(optarg, &p);
333 			if (*p != '\0' || maxwait <= 0)
334 				errx(1, "Bad/invalid maxwait time %s", optarg);
335 			break;
336 		default:
337 			usage();
338 			break;
339 		}
340 	}
341 
342 	if (interval == 0)
343 		interval = (pingflags & F_FLOOD) ? FLOOD_INTVL : 1.0;
344 #ifndef sgi
345 	if (interval < 1.0 && getuid())
346 		errx(1, "Must be superuser to use < 1 sec ping interval");
347 #endif
348 	sec_to_timeval(interval, &interval_tv);
349 
350 	if (npackets != 0) {
351 		npackets += preload;
352 	} else {
353 		npackets = INT_MAX;
354 	}
355 
356 	if (hostind == 0) {
357 		if (optind != argc-1)
358 			usage();
359 		else
360 			hostind = optind;
361 	}
362 	else if (hostind >= argc - 1)
363 		usage();
364 
365 	gethost("", argv[hostind], &whereto, hostname, sizeof(hostname));
366 	if (IN_MULTICAST(ntohl(whereto.sin_addr.s_addr)))
367 		pingflags |= F_MCAST;
368 	if (!(pingflags & F_SOURCE_ROUTE))
369 		(void) memcpy(&send_addr, &whereto, sizeof(send_addr));
370 
371 	loc_addr.sin_family = AF_INET;
372 	loc_addr.sin_addr.s_addr = htonl((127<<24)+1);
373 
374 	if (datalen >= PHDR_LEN)	/* can we time them? */
375 		pingflags |= F_TIMING;
376 	packlen = datalen + 60 + 76;	/* MAXIP + MAXICMP */
377 	if ((packet = (u_char *)malloc(packlen)) == NULL)
378 		err(1, "Out of memory");
379 
380 	if (pingflags & F_PING_FILLED) {
381 		fill();
382 	} else if (pingflags & F_PING_RANDOM) {
383 		rnd_fill();
384 	} else {
385 		for (i = PHDR_LEN; i < datalen; i++)
386 			opack_icmp.icmp_data[i] = i;
387 	}
388 
389 	ident = getpid() & 0xFFFF;
390 
391 	if ((s = socket(AF_INET, SOCK_RAW, IPPROTO_ICMP)) < 0)
392 		err(1, "Cannot create socket");
393 	if (options & SO_DEBUG) {
394 		if (setsockopt(s, SOL_SOCKET, SO_DEBUG, (char *) &on,
395 		    sizeof(on)) == -1)
396 			warn("Can't turn on socket debugging");
397 	}
398 	if (options & SO_DONTROUTE) {
399 		if (setsockopt(s, SOL_SOCKET, SO_DONTROUTE, (char *) &on,
400 		    sizeof(on)) == -1)
401 			warn("SO_DONTROUTE");
402 	}
403 
404 	if (pingflags & F_SOURCE_ROUTE) {
405 		optspace[IPOPT_OPTVAL] = IPOPT_LSRR;
406 		optspace[IPOPT_OLEN] = optlen = 7;
407 		optspace[IPOPT_OFFSET] = IPOPT_MINOFF;
408 		(void) memcpy(&whereto.sin_addr, &optspace[IPOPT_MINOFF-1],
409 		    sizeof(whereto.sin_addr));
410 		optspace[optlen++] = IPOPT_NOP;
411 	}
412 	if (pingflags & F_RECORD_ROUTE) {
413 		optspace[optlen+IPOPT_OPTVAL] = IPOPT_RR;
414 		optspace[optlen+IPOPT_OLEN] = (MAX_IPOPTLEN -1-optlen);
415 		optspace[optlen+IPOPT_OFFSET] = IPOPT_MINOFF;
416 		optlen = MAX_IPOPTLEN;
417 	}
418 	/* this leaves opack_ip 0(mod 4) aligned */
419 	opack_ip = (struct ip *)((char *)&out_pack.o_ip
420 				 + sizeof(out_pack.o_opt)
421 				 - optlen);
422 	(void) memcpy(opack_ip + 1, optspace, optlen);
423 
424 	if (setsockopt(s,IPPROTO_IP,IP_HDRINCL, (char *) &on, sizeof(on)) < 0)
425 		err(1, "Can't set special IP header");
426 
427 	opack_ip->ip_v = IPVERSION;
428 	opack_ip->ip_hl = (sizeof(struct ip)+optlen) >> 2;
429 	opack_ip->ip_tos = tos;
430 	opack_ip->ip_off = (pingflags & F_DF) ? IP_DF : 0;
431 	opack_ip->ip_ttl = ttl ? ttl : MAXTTL;
432 	opack_ip->ip_p = IPPROTO_ICMP;
433 	opack_ip->ip_src = src_addr.sin_addr;
434 	opack_ip->ip_dst = send_addr.sin_addr;
435 
436 	if (pingflags & F_MCAST) {
437 		if (pingflags & F_MCAST_NOLOOP) {
438 			u_char loop = 0;
439 			if (setsockopt(s, IPPROTO_IP, IP_MULTICAST_LOOP,
440 			    (char *) &loop, 1) < 0)
441 				err(1, "Can't disable multicast loopback");
442 		}
443 
444 		if (ttl != 0
445 		    && setsockopt(s, IPPROTO_IP, IP_MULTICAST_TTL,
446 		    (char *) &ttl, 1) < 0)
447 			err(1, "Can't set multicast time-to-live");
448 
449 		if ((pingflags & F_SOURCE_ADDR)
450 		    && setsockopt(s, IPPROTO_IP, IP_MULTICAST_IF,
451 				  (char *) &src_addr.sin_addr,
452 				  sizeof(src_addr.sin_addr)) < 0)
453 			err(1, "Can't set multicast source interface");
454 
455 	} else if (pingflags & F_SOURCE_ADDR) {
456 		if (setsockopt(s, IPPROTO_IP, IP_MULTICAST_IF,
457 			       (char *) &src_addr.sin_addr,
458 			       sizeof(src_addr.sin_addr)) < 0)
459 			err(1, "Can't set source interface/address");
460 	}
461 
462 	(void)printf("PING %s (%s): %d data bytes\n", hostname,
463 		     inet_ntoa(whereto.sin_addr), datalen);
464 
465 	/* When pinging the broadcast address, you can get a lot
466 	 * of answers.  Doing something so evil is useful if you
467 	 * are trying to stress the ethernet, or just want to
468 	 * fill the arp cache to get some stuff for /etc/ethers.
469 	 */
470 	while (0 > setsockopt(s, SOL_SOCKET, SO_RCVBUF,
471 			      (char*)&bufspace, sizeof(bufspace))) {
472 		if ((bufspace -= 4096) == 0)
473 			err(1, "Cannot set the receive buffer size");
474 	}
475 
476 	/* make it possible to send giant probes, but do not worry now
477 	 * if it fails, since we probably won't send giant probes.
478 	 */
479 	(void)setsockopt(s, SOL_SOCKET, SO_SNDBUF,
480 			 (char*)&bufspace, sizeof(bufspace));
481 
482 	(void)signal(SIGINT, prefinish);
483 #ifdef SIGINFO
484 	(void)signal(SIGINFO, prtsig);
485 #else
486 	(void)signal(SIGQUIT, prtsig);
487 #endif
488 	(void)signal(SIGCONT, prtsig);
489 
490 #ifdef sgi
491 	/* run with a non-degrading priority to improve the delay values. */
492 	(void) cap_schedctl(NDPRI, 0, NDPHIMAX);
493 #endif
494 
495 	/* fire off them quickies */
496 	for (i = 0; i < preload; i++) {
497 		(void)gettimeofday(&now, 0);
498 		pinger();
499 	}
500 
501 	doit();
502 	return 0;
503 }
504 
505 
506 static void
507 doit(void)
508 {
509 	int cc;
510 	struct sockaddr_in from;
511 	int fromlen;
512 	double sec, last, d_last;
513 	struct timeval timeout;
514 	fd_set fdmask;
515 
516 
517 	(void)gettimeofday(&clear_cache,0);
518 	if (maxwait != 0) {
519 		last = timeval_to_sec(&clear_cache) + maxwait;
520 		d_last = 0;
521 	} else {
522 		last = 0;
523 		d_last = 365*24*60*60;
524 	}
525 
526 	FD_ZERO(&fdmask);
527 	do {
528 		(void)gettimeofday(&now,0);
529 
530 		if (last != 0)
531 			d_last = last - timeval_to_sec(&now);
532 
533 		if (ntransmitted < npackets && d_last > 0) {
534 			/* send if within 100 usec or late for next packet */
535 			sec = diffsec(&next_tx,&now);
536 			if (sec <= 0.0001
537 			    || (lastrcvd && (pingflags & F_FLOOD))) {
538 				pinger();
539 				sec = diffsec(&next_tx,&now);
540 			}
541 			if (sec < 0.0)
542 				sec = 0.0;
543 			if (d_last < sec)
544 				sec = d_last;
545 
546 		} else {
547 			/* For the last response, wait twice as long as the
548 			 * worst case seen, or 10 times as long as the
549 			 * maximum interpacket interval, whichever is longer.
550 			 */
551 			sec = MAX(2*tmax,10*interval) - diffsec(&now,&last_tx);
552 			if (d_last < sec)
553 				sec = d_last;
554 			if (sec <= 0)
555 				break;
556 		}
557 
558 
559 		sec_to_timeval(sec, &timeout);
560 
561 		FD_SET(s, &fdmask);
562 		cc = select(s+1, &fdmask, 0, 0, &timeout);
563 		if (cc <= 0) {
564 			if (cc < 0) {
565 				if (errno == EINTR)
566 					continue;
567 				jiggle_flush(1);
568 				err(1, "select");
569 			}
570 			continue;
571 		}
572 
573 		fromlen  = sizeof(from);
574 		cc = recvfrom(s, (char *) packet, packlen,
575 			      0, (struct sockaddr *)&from,
576 			      &fromlen);
577 		if (cc < 0) {
578 			if (errno != EINTR) {
579 				jiggle_flush(1);
580 				warn("recvfrom");
581 				(void)fflush(stderr);
582 			}
583 			continue;
584 		}
585 		(void)gettimeofday(&now, 0);
586 		pr_pack(packet, cc, &from);
587 
588 	} while (nreceived < npackets
589 		 && (nreceived == 0 || !(pingflags & F_ONCE)));
590 
591 	finish(0);
592 }
593 
594 
595 static void
596 jiggle_flush(int nl)			/* new line if there are dots */
597 {
598 	int serrno = errno;
599 
600 	if (jiggle_cnt > 0) {
601 		total_jiggled += jiggle_cnt;
602 		jiggle_direction = 1;
603 		do {
604 			(void)putchar('.');
605 		} while (--jiggle_cnt > 0);
606 
607 	} else if (jiggle_cnt < 0) {
608 		total_jiggled -= jiggle_cnt;
609 		jiggle_direction = -1;
610 		do {
611 			(void)putchar('\b');
612 		} while (++jiggle_cnt < 0);
613 	}
614 
615 	if (nl) {
616 		if (total_jiggled != 0)
617 			(void)putchar('\n');
618 		total_jiggled = 0;
619 		jiggle_direction = -1;
620 	}
621 
622 	(void)fflush(stdout);
623 	(void)fflush(stderr);
624 	jiggle_time = now;
625 	errno = serrno;
626 }
627 
628 
629 /* jiggle the cursor for flood-ping
630  */
631 static void
632 jiggle(int delta)
633 {
634 	double dt;
635 
636 	if (pingflags & F_QUIET)
637 		return;
638 
639 	/* do not back up into messages */
640 	if (total_jiggled+jiggle_cnt+delta < 0)
641 		return;
642 
643 	jiggle_cnt += delta;
644 
645 	/* flush the FLOOD dots when things are quiet
646 	 * or occassionally to make the cursor jiggle.
647 	 */
648 	dt = diffsec(&last_tx, &jiggle_time);
649 	if (dt > 0.2 || (dt >= 0.15 && delta*jiggle_direction < 0))
650 		jiggle_flush(0);
651 }
652 
653 
654 /*
655  * Compose and transmit an ICMP ECHO REQUEST packet.  The IP packet
656  * will be added on by the kernel.  The ID field is our UNIX process ID,
657  * and the sequence number is an ascending integer.  The first PHDR_LEN bytes
658  * of the data portion are used to hold a UNIX "timeval" struct in VAX
659  * byte-order, to compute the round-trip time.
660  */
661 static void
662 pinger(void)
663 {
664 	int i, cc, sw;
665 
666 	opack_icmp.icmp_code = 0;
667 	opack_icmp.icmp_seq = htons((u_short)(ntransmitted));
668 
669 	/* clear the cached route in the kernel after an ICMP
670 	 * response such as a Redirect is seen to stop causing
671 	 * more such packets.  Also clear the cached route
672 	 * periodically in case of routing changes that make
673 	 * black holes come and go.
674 	 */
675 	if (clear_cache.tv_sec != now.tv_sec) {
676 		opack_icmp.icmp_type = ICMP_ECHOREPLY;
677 		opack_icmp.icmp_id = ~ident;
678 		opack_icmp.icmp_cksum = 0;
679 		opack_icmp.icmp_cksum = in_cksum((u_short*)&opack_icmp,
680 						 PHDR_LEN);
681 		sw = 0;
682 		if (setsockopt(s,IPPROTO_IP,IP_HDRINCL,
683 			       (char *)&sw,sizeof(sw)) < 0)
684 			err(1, "Can't turn off special IP header");
685 		if (sendto(s, (char *) &opack_icmp, PHDR_LEN, MSG_DONTROUTE,
686 			   (struct sockaddr *)&loc_addr,
687 			   sizeof(struct sockaddr_in)) < 0)
688 			err(1, "failed to clear cached route");
689 		sw = 1;
690 		if (setsockopt(s,IPPROTO_IP,IP_HDRINCL,
691 			       (char *)&sw, sizeof(sw)) < 0)
692 			err(1, "Can't set special IP header");
693 
694 		(void)gettimeofday(&clear_cache,0);
695 	}
696 
697 	opack_icmp.icmp_type = ICMP_ECHO;
698 	opack_icmp.icmp_id = ident;
699 	if (pingflags & F_TIMING)
700 		(void) memcpy(&opack_icmp.icmp_data[0], &now, sizeof(now));
701 	cc = datalen+PHDR_LEN;
702 	opack_icmp.icmp_cksum = 0;
703 	opack_icmp.icmp_cksum = in_cksum((u_short*)&opack_icmp, cc);
704 
705 	cc += opack_ip->ip_hl<<2;
706 	opack_ip->ip_len = cc;
707 	i = sendto(s, (char *) opack_ip, cc, 0,
708 		   (struct sockaddr *)&send_addr, sizeof(struct sockaddr_in));
709 	if (i != cc) {
710 		jiggle_flush(1);
711 		if (i < 0)
712 			warn("sendto");
713 		else
714 			warnx("wrote %s %d chars, ret=%d", hostname, cc, i);
715 		(void)fflush(stderr);
716 	}
717 	lastrcvd = 0;
718 
719 	CLR(ntransmitted);
720 	ntransmitted++;
721 
722 	last_tx = now;
723 	if (next_tx.tv_sec == 0) {
724 		first_tx = now;
725 		next_tx = now;
726 	}
727 
728 	/* Transmit regularly, at always the same microsecond in the
729 	 * second when going at one packet per second.
730 	 * If we are at most 100 ms behind, send extras to get caught up.
731 	 * Otherwise, skip packets we were too slow to send.
732 	 */
733 	if (diffsec(&next_tx, &now) <= interval) {
734 		do {
735 			timevaladd(&next_tx, &interval_tv);
736 		} while (diffsec(&next_tx, &now) < -0.1);
737 	}
738 
739 	if (pingflags & F_FLOOD)
740 		jiggle(1);
741 
742 	/* While the packet is going out, ready buffer for the next
743 	 * packet. Use a fast but not very good random number generator.
744 	 */
745 	if (pingflags & F_PING_RANDOM)
746 		rnd_fill();
747 }
748 
749 
750 static void
751 pr_pack_sub(int cc,
752 	    char *addr,
753 	    int seqno,
754 	    int dupflag,
755 	    int ttl,
756 	    double triptime)
757 {
758 	jiggle_flush(1);
759 
760 	if (pingflags & F_FLOOD)
761 		return;
762 
763 	(void)printf("%d bytes from %s: icmp_seq=%u", cc, addr, seqno);
764 	if (dupflag)
765 		(void)printf(" DUP!");
766 	(void)printf(" ttl=%d", ttl);
767 	if (pingflags & F_TIMING)
768 		(void)printf(" time=%.3f ms", triptime*1000.0);
769 }
770 
771 
772 /*
773  * Print out the packet, if it came from us.  This logic is necessary
774  * because ALL readers of the ICMP socket get a copy of ALL ICMP packets
775  * which arrive ('tis only fair).  This permits multiple copies of this
776  * program to be run without having intermingled output (or statistics!).
777  */
778 static void
779 pr_pack(u_char *buf,
780 	int cc,
781 	struct sockaddr_in *from)
782 {
783 	struct ip *ip;
784 	register struct icmp *icp;
785 	register int i, j;
786 	register u_char *cp;
787 	static int old_rrlen;
788 	static char old_rr[MAX_IPOPTLEN];
789 	int hlen, dupflag = 0, dumped;
790 	double triptime = 0.0;
791 #define PR_PACK_SUB() {if (!dumped) {			\
792 	dumped = 1;					\
793 	pr_pack_sub(cc, inet_ntoa(from->sin_addr),	\
794 		    ntohs((u_short)icp->icmp_seq),	\
795 		    dupflag, ip->ip_ttl, triptime);}}
796 
797 	/* Check the IP header */
798 	ip = (struct ip *) buf;
799 	hlen = ip->ip_hl << 2;
800 	if (cc < hlen + ICMP_MINLEN) {
801 		if (pingflags & F_VERBOSE) {
802 			jiggle_flush(1);
803 			(void)printf("packet too short (%d bytes) from %s\n",
804 				     cc, inet_ntoa(from->sin_addr));
805 		}
806 		return;
807 	}
808 
809 	/* Now the ICMP part */
810 	dumped = 0;
811 	cc -= hlen;
812 	icp = (struct icmp *)(buf + hlen);
813 	if (icp->icmp_type == ICMP_ECHOREPLY
814 	    && icp->icmp_id == ident) {
815 
816 		if (icp->icmp_seq == htons((u_short)(ntransmitted-1)))
817 			lastrcvd = 1;
818 		last_rx = now;
819 		if (first_rx.tv_sec == 0)
820 			first_rx = last_rx;
821 		nreceived++;
822 		if (pingflags & F_TIMING) {
823 			struct timeval tv;
824 			(void) memcpy(&tv, icp->icmp_data, sizeof(tv));
825 			triptime = diffsec(&last_rx, &tv);
826 			tsum += triptime;
827 			if (triptime < tmin)
828 				tmin = triptime;
829 			if (triptime > tmax)
830 				tmax = triptime;
831 		}
832 
833 		if (TST(ntohs((u_short)icp->icmp_seq))) {
834 			nrepeats++, nreceived--;
835 			dupflag=1;
836 		} else {
837 			SET(ntohs((u_short)icp->icmp_seq));
838 		}
839 
840 		if (pingflags & F_QUIET)
841 			return;
842 
843 		if (!(pingflags & F_FLOOD))
844 			PR_PACK_SUB();
845 
846 		/* check the data */
847 		if (datalen > PHDR_LEN
848 		    && !(pingflags & F_PING_RANDOM)
849 		    && memcmp(&icp->icmp_data[PHDR_LEN],
850 			    &opack_icmp.icmp_data[PHDR_LEN],
851 			    datalen-PHDR_LEN)) {
852 			for (i=PHDR_LEN; i<datalen; i++) {
853 				if (icp->icmp_data[PHDR_LEN+i]
854 				    != opack_icmp.icmp_data[PHDR_LEN+i])
855 					break;
856 			}
857 			PR_PACK_SUB();
858 			(void)printf("\nwrong data byte #%d should have been"
859 				     " %#x but was %#x",
860 				     i, (u_char)opack_icmp.icmp_data[i],
861 				     (u_char)icp->icmp_data[i]);
862 			for (i=PHDR_LEN; i<datalen; i++) {
863 				if ((i%16) == PHDR_LEN)
864 					(void)printf("\n\t");
865 				(void)printf("%2x ",(u_char)icp->icmp_data[i]);
866 			}
867 		}
868 
869 	} else {
870 		if (!pr_icmph(icp, from, cc))
871 			return;
872 		dumped = 2;
873 	}
874 
875 	/* Display any IP options */
876 	cp = buf + sizeof(struct ip);
877 	while (hlen > (int)sizeof(struct ip)) {
878 		switch (*cp) {
879 		case IPOPT_EOL:
880 			hlen = 0;
881 			break;
882 		case IPOPT_LSRR:
883 			hlen -= 2;
884 			j = *++cp;
885 			++cp;
886 			j -= IPOPT_MINOFF;
887 			if (j <= 0)
888 				continue;
889 			if (dumped <= 1) {
890 				j = ((j+3)/4)*4;
891 				hlen -= j;
892 				cp += j;
893 				break;
894 			}
895 			PR_PACK_SUB();
896 			(void)printf("\nLSRR: ");
897 			for (;;) {
898 				pr_saddr("\t%s", cp);
899 				cp += 4;
900 				hlen -= 4;
901 				j -= 4;
902 				if (j <= 0)
903 					break;
904 				(void)putchar('\n');
905 			}
906 			break;
907 		case IPOPT_RR:
908 			j = *++cp;	/* get length */
909 			i = *++cp;	/* and pointer */
910 			hlen -= 2;
911 			if (i > j)
912 				i = j;
913 			i -= IPOPT_MINOFF;
914 			if (i <= 0)
915 				continue;
916 			if (dumped <= 1) {
917 				if (i == old_rrlen
918 				    && !memcmp(cp, old_rr, i)) {
919 					if (dumped)
920 					    (void)printf("\t(same route)");
921 					j = ((i+3)/4)*4;
922 					hlen -= j;
923 					cp += j;
924 					break;
925 				}
926 				old_rrlen = i;
927 				(void) memcpy(old_rr, cp, i);
928 			}
929 			if (!dumped) {
930 				jiggle_flush(1);
931 				(void)printf("RR: ");
932 				dumped = 1;
933 			} else {
934 				(void)printf("\nRR: ");
935 			}
936 			for (;;) {
937 				pr_saddr("\t%s", cp);
938 				cp += 4;
939 				hlen -= 4;
940 				i -= 4;
941 				if (i <= 0)
942 					break;
943 				(void)putchar('\n');
944 			}
945 			break;
946 		case IPOPT_NOP:
947 			if (dumped <= 1)
948 				break;
949 			PR_PACK_SUB();
950 			(void)printf("\nNOP");
951 			break;
952 #ifdef sgi
953 		case IPOPT_SECURITY:	/* RFC 1108 RIPSO BSO */
954 		case IPOPT_ESO:		/* RFC 1108 RIPSO ESO */
955 		case IPOPT_CIPSO:	/* Commercial IPSO */
956 			if ((sysconf(_SC_IP_SECOPTS)) > 0) {
957 				i = (unsigned)cp[1];
958 				hlen -= i - 1;
959 				PR_PACK_SUB();
960 				(void)printf("\nSEC:");
961 				while (i--) {
962 					(void)printf(" %02x", *cp++);
963 				}
964 				cp--;
965 				break;
966 			}
967 #endif
968 		default:
969 			PR_PACK_SUB();
970 			(void)printf("\nunknown option %x", *cp);
971 			break;
972 		}
973 		hlen--;
974 		cp++;
975 	}
976 
977 	if (dumped) {
978 		(void)putchar('\n');
979 		(void)fflush(stdout);
980 	} else {
981 		jiggle(-1);
982 	}
983 }
984 
985 
986 /* Compute the IP checksum
987  *	This assumes the packet is less than 32K long.
988  */
989 static u_short
990 in_cksum(u_short *p,
991 	 u_int len)
992 {
993 	u_int sum = 0;
994 	int nwords = len >> 1;
995 
996 	while (nwords-- != 0)
997 		sum += *p++;
998 
999 	if (len & 1) {
1000 		union {
1001 			u_short w;
1002 			u_char c[2];
1003 		} u;
1004 		u.c[0] = *(u_char *)p;
1005 		u.c[1] = 0;
1006 		sum += u.w;
1007 	}
1008 
1009 	/* end-around-carry */
1010 	sum = (sum >> 16) + (sum & 0xffff);
1011 	sum += (sum >> 16);
1012 	return (~sum);
1013 }
1014 
1015 
1016 /*
1017  * compute the difference of two timevals in seconds
1018  */
1019 static double
1020 diffsec(struct timeval *now,
1021 	struct timeval *then)
1022 {
1023 	return ((now->tv_sec - then->tv_sec)*1.0
1024 		+ (now->tv_usec - then->tv_usec)/1000000.0);
1025 }
1026 
1027 
1028 static void
1029 timevaladd(struct timeval *t1,
1030 	   struct timeval *t2)
1031 {
1032 
1033 	t1->tv_sec += t2->tv_sec;
1034 	if ((t1->tv_usec += t2->tv_usec) > 1000000) {
1035 		t1->tv_sec++;
1036 		t1->tv_usec -= 1000000;
1037 	}
1038 }
1039 
1040 
1041 static void
1042 sec_to_timeval(const double sec, struct timeval *tp)
1043 {
1044 	tp->tv_sec = sec;
1045 	tp->tv_usec = (sec - tp->tv_sec) * 1000000.0;
1046 }
1047 
1048 static double
1049 timeval_to_sec(const struct timeval *tp)
1050 {
1051 	return tp->tv_sec + tp->tv_usec / 1000000.0;
1052 }
1053 
1054 
1055 /*
1056  * Print statistics.
1057  * Heavily buffered STDIO is used here, so that all the statistics
1058  * will be written with 1 sys-write call.  This is nice when more
1059  * than one copy of the program is running on a terminal;  it prevents
1060  * the statistics output from becomming intermingled.
1061  */
1062 static void
1063 summary(int header)
1064 {
1065 	jiggle_flush(1);
1066 
1067 	if (header)
1068 		(void)printf("\n----%s PING Statistics----\n", hostname);
1069 	(void)printf("%d packets transmitted, ", ntransmitted);
1070 	(void)printf("%d packets received, ", nreceived);
1071 	if (nrepeats)
1072 		(void)printf("+%d duplicates, ", nrepeats);
1073 	if (ntransmitted) {
1074 		if (nreceived > ntransmitted)
1075 			(void)printf("-- somebody's printing up packets!");
1076 		else
1077 			(void)printf("%d%% packet loss",
1078 				     (int) (((ntransmitted-nreceived)*100) /
1079 					    ntransmitted));
1080 	}
1081 	(void)printf("\n");
1082 	if (nreceived && (pingflags & F_TIMING)) {
1083 		(void)printf("round-trip min/avg/max = %.3f/%.3f/%.3f ms\n",
1084 			     tmin*1000.0,
1085 			     (tsum/(nreceived+nrepeats))*1000.0,
1086 			     tmax*1000.0);
1087 		if (pingflags & F_FLOOD) {
1088 			double r = diffsec(&last_rx, &first_rx);
1089 			double t = diffsec(&last_tx, &first_tx);
1090 			if (r == 0)
1091 				r = 0.0001;
1092 			if (t == 0)
1093 				t = 0.0001;
1094 			(void)printf("  %.1f packets/sec sent, "
1095 				     " %.1f packets/sec received\n",
1096 				     ntransmitted/t, nreceived/r);
1097 		}
1098 	}
1099 }
1100 
1101 
1102 /*
1103  * Print statistics when SIGINFO is received.
1104  */
1105 /* ARGSUSED */
1106 static void
1107 prtsig(int s)
1108 {
1109 	summary(0);
1110 #ifdef SIGINFO
1111 	(void)signal(SIGINFO, prtsig);
1112 #else
1113 	(void)signal(SIGQUIT, prtsig);
1114 #endif
1115 }
1116 
1117 
1118 /*
1119  * On the first SIGINT, allow any outstanding packets to dribble in
1120  */
1121 static void
1122 prefinish(int s)
1123 {
1124 	if (lastrcvd			/* quit now if caught up */
1125 	    || nreceived == 0)		/* or if remote is dead */
1126 		finish(0);
1127 
1128 	signal(s, finish);		/* do this only the 1st time */
1129 
1130 	if (npackets > ntransmitted)	/* let the normal limit work */
1131 		npackets = ntransmitted;
1132 }
1133 
1134 
1135 /*
1136  * Print statistics and give up.
1137  */
1138 /* ARGSUSED */
1139 static void
1140 finish(int s)
1141 {
1142 #if defined(SIGINFO) && defined(NOKERNINFO)
1143 	struct termios ts;
1144 
1145 	if (reset_kerninfo && tcgetattr (0, &ts) != -1) {
1146 		ts.c_lflag &= ~NOKERNINFO;
1147 		tcsetattr (0, TCSANOW, &ts);
1148 	}
1149 	(void)signal(SIGINFO, SIG_IGN);
1150 #else
1151 	(void)signal(SIGQUIT, SIG_DFL);
1152 #endif
1153 
1154 	summary(1);
1155 	exit(nreceived > 0 ? 0 : 2);
1156 }
1157 
1158 
1159 static int				/* 0=do not print it */
1160 ck_pr_icmph(struct icmp *icp,
1161 	    struct sockaddr_in *from,
1162 	    int cc,
1163 	    int override)		/* 1=override VERBOSE if interesting */
1164 {
1165 	int	hlen;
1166 	struct ip ip;
1167 	struct icmp icp2;
1168 	int res;
1169 
1170 	if (pingflags & F_VERBOSE) {
1171 		res = 1;
1172 		jiggle_flush(1);
1173 	} else {
1174 		res = 0;
1175 	}
1176 
1177 	(void) memcpy(&ip, icp->icmp_data, sizeof(ip));
1178 	hlen = ip.ip_hl << 2;
1179 	if (ip.ip_p == IPPROTO_ICMP
1180 	    && hlen + 6 <= cc) {
1181 		(void) memcpy(&icp2, &icp->icmp_data[hlen], sizeof(icp2));
1182 		if (icp2.icmp_id == ident) {
1183 			/* remember to clear route cached in kernel
1184 			 * if this ICMP message was for one of our packet.
1185 			 */
1186 			clear_cache.tv_sec = 0;
1187 
1188 			if (!res && override
1189 			    && (pingflags & (F_QUIET|F_SEMI_QUIET)) == 0) {
1190 				jiggle_flush(1);
1191 				(void)printf("%d bytes from %s: ",
1192 					     cc, pr_addr(&from->sin_addr));
1193 				res = 1;
1194 			}
1195 		}
1196 	}
1197 
1198 	return res;
1199 }
1200 
1201 
1202 /*
1203  *  Print a descriptive string about an ICMP header other than an echo reply.
1204  */
1205 static int				/* 0=printed nothing */
1206 pr_icmph(struct icmp *icp,
1207 	 struct sockaddr_in *from,
1208 	 int cc)
1209 {
1210 	switch (icp->icmp_type ) {
1211 	case ICMP_UNREACH:
1212 		if (!ck_pr_icmph(icp, from, cc, 1))
1213 			return 0;
1214 		switch (icp->icmp_code) {
1215 		case ICMP_UNREACH_NET:
1216 			(void)printf("Destination Net Unreachable");
1217 			break;
1218 		case ICMP_UNREACH_HOST:
1219 			(void)printf("Destination Host Unreachable");
1220 			break;
1221 		case ICMP_UNREACH_PROTOCOL:
1222 			(void)printf("Destination Protocol Unreachable");
1223 			break;
1224 		case ICMP_UNREACH_PORT:
1225 			(void)printf("Destination Port Unreachable");
1226 			break;
1227 		case ICMP_UNREACH_NEEDFRAG:
1228 			(void)printf("frag needed and DF set.  Next MTU=%d",
1229 			       icp->icmp_nextmtu);
1230 			break;
1231 		case ICMP_UNREACH_SRCFAIL:
1232 			(void)printf("Source Route Failed");
1233 			break;
1234 		case ICMP_UNREACH_NET_UNKNOWN:
1235 			(void)printf("Unreachable unknown net");
1236 			break;
1237 		case ICMP_UNREACH_HOST_UNKNOWN:
1238 			(void)printf("Unreachable unknown host");
1239 			break;
1240 		case ICMP_UNREACH_ISOLATED:
1241 			(void)printf("Unreachable host isolated");
1242 			break;
1243 		case ICMP_UNREACH_NET_PROHIB:
1244 			(void)printf("Net prohibited access");
1245 			break;
1246 		case ICMP_UNREACH_HOST_PROHIB:
1247 			(void)printf("Host prohibited access");
1248 			break;
1249 		case ICMP_UNREACH_TOSNET:
1250 			(void)printf("Bad TOS for net");
1251 			break;
1252 		case ICMP_UNREACH_TOSHOST:
1253 			(void)printf("Bad TOS for host");
1254 			break;
1255 		case 13:
1256 			(void)printf("Communication prohibited");
1257 			break;
1258 		case 14:
1259 			(void)printf("Host precedence violation");
1260 			break;
1261 		case 15:
1262 			(void)printf("Precedence cutoff");
1263 			break;
1264 		default:
1265 			(void)printf("Bad Destination Unreachable Code: %d",
1266 				     icp->icmp_code);
1267 			break;
1268 		}
1269 		/* Print returned IP header information */
1270 		pr_retip(icp, cc);
1271 		break;
1272 
1273 	case ICMP_SOURCEQUENCH:
1274 		if (!ck_pr_icmph(icp, from, cc, 1))
1275 			return 0;
1276 		(void)printf("Source Quench");
1277 		pr_retip(icp, cc);
1278 		break;
1279 
1280 	case ICMP_REDIRECT:
1281 		if (!ck_pr_icmph(icp, from, cc, 1))
1282 			return 0;
1283 		switch (icp->icmp_code) {
1284 		case ICMP_REDIRECT_NET:
1285 			(void)printf("Redirect: Network");
1286 			break;
1287 		case ICMP_REDIRECT_HOST:
1288 			(void)printf("Redirect: Host");
1289 			break;
1290 		case ICMP_REDIRECT_TOSNET:
1291 			(void)printf("Redirect: Type of Service and Network");
1292 			break;
1293 		case ICMP_REDIRECT_TOSHOST:
1294 			(void)printf("Redirect: Type of Service and Host");
1295 			break;
1296 		default:
1297 			(void)printf("Redirect: Bad Code: %d", icp->icmp_code);
1298 			break;
1299 		}
1300 		(void)printf(" New addr: %s",
1301 			     pr_addr(&icp->icmp_hun.ih_gwaddr));
1302 		pr_retip(icp, cc);
1303 		break;
1304 
1305 	case ICMP_ECHO:
1306 		if (!ck_pr_icmph(icp, from, cc, 0))
1307 			return 0;
1308 		(void)printf("Echo Request: ID=%d seq=%d",
1309 			     icp->icmp_id, icp->icmp_seq);
1310 		break;
1311 
1312 	case ICMP_ECHOREPLY:
1313 		/* displaying other's pings is too noisey */
1314 #if 0
1315 		if (!ck_pr_icmph(icp, from, cc, 0))
1316 			return 0;
1317 		(void)printf("Echo Reply: ID=%d seq=%d",
1318 			     icp->icmp_id, icp->icmp_seq);
1319 		break;
1320 #else
1321 		return 0;
1322 #endif
1323 
1324 	case ICMP_ROUTERADVERT:
1325 		if (!ck_pr_icmph(icp, from, cc, 0))
1326 			return 0;
1327 		(void)printf("Router Discovery Advert");
1328 		break;
1329 
1330 	case ICMP_ROUTERSOLICIT:
1331 		if (!ck_pr_icmph(icp, from, cc, 0))
1332 			return 0;
1333 		(void)printf("Router Discovery Solicit");
1334 		break;
1335 
1336 	case ICMP_TIMXCEED:
1337 		if (!ck_pr_icmph(icp, from, cc, 1))
1338 			return 0;
1339 		switch (icp->icmp_code ) {
1340 		case ICMP_TIMXCEED_INTRANS:
1341 			(void)printf("Time To Live exceeded");
1342 			break;
1343 		case ICMP_TIMXCEED_REASS:
1344 			(void)printf("Frag reassembly time exceeded");
1345 			break;
1346 		default:
1347 			(void)printf("Time exceeded, Bad Code: %d",
1348 				     icp->icmp_code);
1349 			break;
1350 		}
1351 		pr_retip(icp, cc);
1352 		break;
1353 
1354 	case ICMP_PARAMPROB:
1355 		if (!ck_pr_icmph(icp, from, cc, 1))
1356 			return 0;
1357 		(void)printf("Parameter problem: pointer = 0x%02x",
1358 			     icp->icmp_hun.ih_pptr);
1359 		pr_retip(icp, cc);
1360 		break;
1361 
1362 	case ICMP_TSTAMP:
1363 		if (!ck_pr_icmph(icp, from, cc, 0))
1364 			return 0;
1365 		(void)printf("Timestamp");
1366 		break;
1367 
1368 	case ICMP_TSTAMPREPLY:
1369 		if (!ck_pr_icmph(icp, from, cc, 0))
1370 			return 0;
1371 		(void)printf("Timestamp Reply");
1372 		break;
1373 
1374 	case ICMP_IREQ:
1375 		if (!ck_pr_icmph(icp, from, cc, 0))
1376 			return 0;
1377 		(void)printf("Information Request");
1378 		break;
1379 
1380 	case ICMP_IREQREPLY:
1381 		if (!ck_pr_icmph(icp, from, cc, 0))
1382 			return 0;
1383 		(void)printf("Information Reply");
1384 		break;
1385 
1386 	case ICMP_MASKREQ:
1387 		if (!ck_pr_icmph(icp, from, cc, 0))
1388 			return 0;
1389 		(void)printf("Address Mask Request");
1390 		break;
1391 
1392 	case ICMP_MASKREPLY:
1393 		if (!ck_pr_icmph(icp, from, cc, 0))
1394 			return 0;
1395 		(void)printf("Address Mask Reply");
1396 		break;
1397 
1398 	default:
1399 		if (!ck_pr_icmph(icp, from, cc, 0))
1400 			return 0;
1401 		(void)printf("Bad ICMP type: %d", icp->icmp_type);
1402 		if (pingflags & F_VERBOSE)
1403 			pr_iph(icp, cc);
1404 	}
1405 
1406 	return 1;
1407 }
1408 
1409 
1410 /*
1411  *  Print an IP header with options.
1412  */
1413 static void
1414 pr_iph(struct icmp *icp,
1415        int cc)
1416 {
1417 	int	hlen;
1418 	u_char	*cp;
1419 	struct ip ip;
1420 
1421 	(void) memcpy(&ip, icp->icmp_data, sizeof(ip));
1422 
1423 	hlen = ip.ip_hl << 2;
1424 	cp = (u_char *) &icp->icmp_data[20];	/* point to options */
1425 
1426 	(void)printf("\n Vr HL TOS  Len   ID Flg  off TTL Pro  cks      Src	     Dst\n");
1427 	(void)printf("  %1x  %1x  %02x %04x %04x",
1428 		     ip.ip_v, ip.ip_hl, ip.ip_tos, ip.ip_len, ip.ip_id);
1429 	(void)printf("   %1x %04x",
1430 		     ((ip.ip_off)&0xe000)>>13, (ip.ip_off)&0x1fff);
1431 	(void)printf("  %02x  %02x %04x",
1432 		     ip.ip_ttl, ip.ip_p, ip.ip_sum);
1433 	(void)printf(" %15s ",
1434 		     inet_ntoa(*(struct in_addr *)&ip.ip_src.s_addr));
1435 	(void)printf(" %s ", inet_ntoa(*(struct in_addr *)&ip.ip_dst.s_addr));
1436 	/* dump any option bytes */
1437 	while (hlen-- > 20 && cp < (u_char*)icp+cc) {
1438 		(void)printf("%02x", *cp++);
1439 	}
1440 }
1441 
1442 /*
1443  * Print an ASCII host address starting from a string of bytes.
1444  */
1445 static void
1446 pr_saddr(char *pat,
1447 	 u_char *cp)
1448 {
1449 	register n_long l;
1450 	struct in_addr addr;
1451 
1452 	l = (u_char)*++cp;
1453 	l = (l<<8) + (u_char)*++cp;
1454 	l = (l<<8) + (u_char)*++cp;
1455 	l = (l<<8) + (u_char)*++cp;
1456 	addr.s_addr = htonl(l);
1457 	(void)printf(pat, (l == 0) ? "0.0.0.0" : pr_addr(&addr));
1458 }
1459 
1460 
1461 /*
1462  *  Return an ASCII host address
1463  *  as a dotted quad and optionally with a hostname
1464  */
1465 static char *
1466 pr_addr(struct in_addr *addr)		/* in network order */
1467 {
1468 	struct	hostent	*hp;
1469 	static	char buf[MAXHOSTNAMELEN+4+16+1];
1470 
1471 	if ((pingflags & F_NUMERIC)
1472 	    || !(hp = gethostbyaddr((char *)addr, sizeof(*addr), AF_INET))) {
1473 		(void)sprintf(buf, "%s", inet_ntoa(*addr));
1474 	} else {
1475 		(void)sprintf(buf, "%s (%s)", hp->h_name, inet_ntoa(*addr));
1476 	}
1477 
1478 	return buf;
1479 }
1480 
1481 /*
1482  *  Dump some info on a returned (via ICMP) IP packet.
1483  */
1484 static void
1485 pr_retip(struct icmp *icp,
1486 	 int cc)
1487 {
1488 	int	hlen;
1489 	u_char	*cp;
1490 	struct ip ip;
1491 
1492 	(void) memcpy(&ip, icp->icmp_data, sizeof(ip));
1493 
1494 	if (pingflags & F_VERBOSE)
1495 		pr_iph(icp, cc);
1496 
1497 	hlen = ip.ip_hl << 2;
1498 	cp = (u_char *) &icp->icmp_data[hlen];
1499 
1500 	if (ip.ip_p == IPPROTO_TCP) {
1501 		if (pingflags & F_VERBOSE)
1502 			(void)printf("\n  TCP: from port %u, to port %u",
1503 				     (*cp*256+*(cp+1)), (*(cp+2)*256+*(cp+3)));
1504 	} else if (ip.ip_p == IPPROTO_UDP) {
1505 		if (pingflags & F_VERBOSE)
1506 			(void)printf("\n  UDP: from port %u, to port %u",
1507 				     (*cp*256+*(cp+1)), (*(cp+2)*256+*(cp+3)));
1508 	} else if (ip.ip_p == IPPROTO_ICMP) {
1509 		struct icmp icp2;
1510 		(void) memcpy(&icp2, cp, sizeof(icp2));
1511 		if (icp2.icmp_type == ICMP_ECHO) {
1512 			if (pingflags & F_VERBOSE)
1513 				(void)printf("\n  ID=%u icmp_seq=%u",
1514 					     icp2.icmp_id,
1515 					     icp2.icmp_seq);
1516 			else
1517 				(void)printf(" for icmp_seq=%u",
1518 					     icp2.icmp_seq);
1519 		}
1520 	}
1521 }
1522 
1523 static void
1524 fill(void)
1525 {
1526 	register int i, j, k;
1527 	char *cp;
1528 	int pat[16];
1529 
1530 	for (cp = fill_pat; *cp != '\0'; cp++) {
1531 		if (!isxdigit(*cp))
1532 			break;
1533 	}
1534 	if (cp == fill_pat || *cp != '\0' || (cp-fill_pat) > 16*2) {
1535 		(void)fflush(stdout);
1536 		errx(1, "\"-p %s\": patterns must be specified with"
1537 		     " 1-32 hex digits\n",
1538 		     fill_pat);
1539 	}
1540 
1541 	i = sscanf(fill_pat,
1542 		   "%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x",
1543 		    &pat[0], &pat[1], &pat[2], &pat[3],
1544 		    &pat[4], &pat[5], &pat[6], &pat[7],
1545 		    &pat[8], &pat[9], &pat[10], &pat[11],
1546 		    &pat[12], &pat[13], &pat[14], &pat[15]);
1547 
1548 	for (k=PHDR_LEN, j = 0; k <= datalen; k++) {
1549 		opack_icmp.icmp_data[k] = pat[j];
1550 		if (++j >= i)
1551 			j = 0;
1552 	}
1553 
1554 	if (!(pingflags & F_QUIET)) {
1555 		(void)printf("PATTERN: 0x");
1556 		for (j=0; j<i; j++)
1557 			(void)printf("%02x",
1558 				     (u_char)opack_icmp.icmp_data[PHDR_LEN+j]);
1559 		(void)printf("\n");
1560 	}
1561 
1562 }
1563 
1564 
1565 static void
1566 rnd_fill(void)
1567 {
1568 	static u_int rnd;
1569 	int i;
1570 
1571 	for (i = PHDR_LEN; i < datalen; i++) {
1572 		rnd = (314157*rnd + 66329) & 0xffff;
1573 		opack_icmp.icmp_data[i] = rnd>>8;
1574 	}
1575 }
1576 
1577 static void
1578 gethost(const char *arg,
1579 	const char *name,
1580 	struct sockaddr_in *sa,
1581 	char *realname,
1582 	int realname_len)
1583 {
1584 	struct hostent *hp;
1585 
1586 	bzero(sa, sizeof(*sa));
1587 	sa->sin_family = AF_INET;
1588 
1589 	/* If it is an IP address, try to convert it to a name to
1590 	 * have something nice to display.
1591 	 */
1592 	if (inet_aton(name, &sa->sin_addr) != 0) {
1593 		if (realname) {
1594 			if (pingflags & F_NUMERIC)
1595 				hp = 0;
1596 			else
1597 				hp = gethostbyaddr((char *)&sa->sin_addr,
1598 						   sizeof(sa->sin_addr),
1599 						   AF_INET);
1600 			(void)strncpy(realname, hp ? hp->h_name : name,
1601 				      realname_len);
1602 			realname[realname_len-1] = '\0';
1603 		}
1604 		return;
1605 	}
1606 
1607 	hp = gethostbyname(name);
1608 	if (!hp)
1609 		errx(1, "Cannot resolve \"%s\" (%s)",name,hstrerror(h_errno));
1610 
1611 	if (hp->h_addrtype != AF_INET)
1612 		errx(1, "%s only supported with IP", arg);
1613 
1614 	bcopy(hp->h_addr, &sa->sin_addr, sizeof(sa->sin_addr));
1615 
1616 	if (realname) {
1617 		(void)strncpy(realname, hp->h_name, realname_len);
1618 		realname[realname_len-1] = '\0';
1619 	}
1620 }
1621 
1622 
1623 static void
1624 usage(void)
1625 {
1626 	(void)fprintf(stderr, "Usage: \n"
1627 		      "%s [-dDfnqrvRLP] [-c count] [-s size] [-l preload]"
1628 		      " [-p pattern]\n"
1629 		      "     [-i interval] [-i maxwait] [-t tos] [-T ttl]"
1630 		      " [-I addr] [-g gateway] host\n",
1631 		      __progname);
1632 	exit(1);
1633 }
1634