xref: /titanic_51/usr/src/cmd/cmd-inet/usr.sbin/traceroute/traceroute.c (revision a8ae99647dd4d540346030718e08a083b0fbdf42)
1 /*
2  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
3  * Use is subject to license terms.
4  */
5 
6 /*
7  * Copyright (c) 1988, 1989, 1991, 1994, 1995, 1996, 1997
8  *	The Regents of the University of California.  All rights reserved.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that: (1) source code distributions
12  * retain the above copyright notice and this paragraph in its entirety, (2)
13  * distributions including binary code include the above copyright notice and
14  * this paragraph in its entirety in the documentation or other materials
15  * provided with the distribution, and (3) all advertising materials mentioning
16  * features or use of this software display the following acknowledgement:
17  * ``This product includes software developed by the University of California,
18  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
19  * the University nor the names of its contributors may be used to endorse
20  * or promote products derived from this software without specific prior
21  * written permission.
22  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
23  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
24  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
25  *
26  *
27  * @(#)$Header: traceroute.c,v 1.49 97/06/13 02:30:23 leres Exp $ (LBL)
28  */
29 
30 #pragma ident	"%Z%%M%	%I%	%E% SMI"
31 
32 #include <sys/param.h>
33 #include <sys/file.h>
34 #include <sys/ioctl.h>
35 #include <sys/socket.h>
36 #include <sys/time.h>
37 #include <sys/sysmacros.h>
38 
39 #include <netinet/in_systm.h>
40 #include <netinet/in.h>
41 #include <netinet/ip.h>
42 #include <netinet/ip_var.h>
43 #include <netinet/ip_icmp.h>
44 #include <netinet/udp.h>
45 #include <netinet/udp_var.h>
46 #include <netinet/ip6.h>
47 #include <netinet/icmp6.h>
48 
49 #include <arpa/inet.h>
50 
51 #include <ctype.h>
52 #include <errno.h>
53 #include <malloc.h>
54 #include <memory.h>
55 #include <netdb.h>
56 #include <stdio.h>
57 #include <stdlib.h>
58 #include <strings.h>
59 #include <unistd.h>
60 #include <libintl.h>
61 #include <locale.h>
62 #include <signal.h>
63 #include <setjmp.h>
64 #include <limits.h>
65 #include <zone.h>
66 
67 #include <priv_utils.h>
68 
69 
70 #include <ifaddrlist.h>
71 #include "traceroute.h"
72 
73 #define	MAX_SEQ			65535	/* max sequence value for ICMP */
74 #define	MAX_TRAFFIC_CLASS	255	/* max traffic class for IPv6 */
75 #define	MAX_FLOW_LABEL		0xFFFFF	/* max flow label for IPv6 */
76 #define	MAX_TOS			255	/* max type-of-service for IPv4 */
77 #define	STR_LEN			30
78 
79 /* store the information about a host */
80 struct hostinfo {
81 	char *name;		/* hostname */
82 	int family;		/* address family of the IP addresses */
83 	int num_addr;			/* number of IP addresses */
84 	union any_in_addr *addrs;	/* list of IP addresses */
85 };
86 
87 /* used to store a bunch of protocol specific values */
88 struct pr_set {
89 	int family;		/* AF_INET or AF_INET6 */
90 	char name[STR_LEN];	/* "IPv4" or "IPv6" */
91 	char icmp[STR_LEN];	/* "icmp" or "ipv6-icmp" */
92 	int icmp_minlen;
93 	int addr_len;
94 	int ip_hdr_len;
95 	int packlen;
96 	int sock_size;		/* size of sockaddr_in or sockaddr_in6 */
97 	struct sockaddr *to;
98 	struct sockaddr *from;
99 	void *from_sin_addr;
100 	union any_in_addr *gwIPlist;
101 	/* pointers to v4/v6 functions */
102 	struct ip *(*set_buffers_fn) (int);
103 	int (*check_reply_fn)(struct msghdr *, int, int, uchar_t *, uchar_t *);
104 	boolean_t (*print_icmp_other_fn)(uchar_t, uchar_t);
105 	void (*print_addr_fn)(uchar_t *, int, struct sockaddr *);
106 
107 };
108 
109 /*
110  * LBNL bug fixed: in LBNL traceroute 'uchar_t packet[512];'
111  * Not sufficient to hold the complete packet for ECHO REPLY of a big probe.
112  * Packet size is reported incorrectly in such a case.
113  * Also this buffer needs to be 32 bit aligned. In the future the alignment
114  * requirement will be increased to 64 bit. So, let's use 64 bit alignment now.
115  */
116 static uint64_t packet[(IP_MAXPACKET + 1)/8];	/* received packet */
117 
118 static struct ip *outip4;	/* output buffer to send as an IPv4 datagram */
119 static struct ip *outip6;	/* output buffer to send as an IPv6 datagram */
120 
121 /* Used to store the ancillary data that comes with the received packets */
122 static uint64_t ancillary_data[(IP_MAXPACKET + 1)/8];
123 
124 /* first get the gw names, later you'll resolve them based on the family */
125 static char *gwlist[MAXMAX_GWS];		/* gateway names list */
126 static union any_in_addr gwIPlist[MAX_GWS];	/* gateway IPv4 address list */
127 static union any_in_addr gwIP6list[MAX_GWS6];	/* gateway IPv6 address list */
128 
129 static int family_input = AF_UNSPEC;	/* User supplied protocol family */
130 static int rcvsock4;		/* receive (icmp) socket file descriptor */
131 static int sndsock4;		/* send (udp/icmp) socket file descriptor */
132 static int rcvsock6;		/* receive (icmp6) socket file descriptor */
133 static int sndsock6;		/* send (udp6/icmp6) socket file descriptor */
134 int gw_count = 0;		/* number of gateways */
135 static struct sockaddr_in whereto;	/* Who to try to reach */
136 static struct sockaddr_in6 whereto6;
137 static struct sockaddr_in wherefrom;	/* Who we are */
138 static struct sockaddr_in6 wherefrom6;
139 static int packlen_input = 0;		/* user input for packlen */
140 
141 char *prog;
142 static char *source_input = NULL; /* this is user arg. source, doesn't change */
143 static char *source = NULL;	/* this gets modified after name lookup */
144 char *hostname;
145 static char *device = NULL;   	/* interface name */
146 static struct pr_set *pr4;	/* protocol info for IPv4 */
147 static struct pr_set *pr6;	/* protocol info for IPv6 */
148 static struct ifaddrlist *al4;	/* list of interfaces */
149 static struct ifaddrlist *al6;	/* list of interfaces */
150 static uint_t if_index = 0;	/* interface index */
151 static int num_v4 = 0;		/* count of IPv4 addresses */
152 static int num_v6 = 0;		/* count of IPv6 addresses */
153 static int num_ifs4 = 0;	/* count of local IPv4 interfaces */
154 static int num_ifs6 = 0;	/* count of local IPv6 interfaces */
155 
156 static int nprobes = 3;		/* number of probes */
157 static int max_ttl = 30;	/* max number of hops */
158 static int first_ttl = 1;	/* initial number of hops */
159 ushort_t ident;			/* used to authenticate replies */
160 ushort_t port = 32768 + 666;	/* start udp dest port # for probe packets */
161 
162 static int options = 0;		/* socket options */
163 boolean_t verbose = _B_FALSE;	/* verbose output */
164 static int waittime = 5;	/* time to wait for response (in seconds) */
165 static struct timeval delay = {0, 0}; /* delay between consecutive probe */
166 boolean_t nflag = _B_FALSE;	/* print addresses numerically */
167 static boolean_t showttl = _B_FALSE; /* print the ttl(hop limit) of recvd pkt */
168 boolean_t useicmp = _B_FALSE;  	/* use icmp echo instead of udp packets */
169 boolean_t docksum = _B_TRUE;	/* calculate checksums */
170 static boolean_t collect_stat = _B_FALSE;	/* print statistics */
171 boolean_t settos = _B_FALSE;   	/* set type-of-service field */
172 static int max_timeout = 5;	/* quit after this consecutive timeouts */
173 static boolean_t probe_all = _B_FALSE;	/* probe all the IFs of the target */
174 static boolean_t pick_src = _B_FALSE;	/* traceroute picks the src address */
175 
176 /*
177  * flow and class are specific to IPv6, tos and off are specific to IPv4.
178  * Each protocol uses the ones that are specific to itself, and ignores
179  * others.
180  */
181 static uint_t flow = 0;		/* IPv6 flow info */
182 static uint_t class = 0;	/* IPv6 class */
183 uchar_t tos = 0;		/* IPv4 type-of-service */
184 ushort_t off = 0;		/* set DF bit */
185 
186 static jmp_buf env;		/* stack environment for longjmp() */
187 boolean_t raw_req;		/* if sndsock for IPv4 must be raw */
188 
189 /* Forwards */
190 static uint_t calc_packetlen(int, struct pr_set *);
191 extern int check_reply(struct msghdr *, int, int, uchar_t *, uchar_t *);
192 extern int check_reply6(struct msghdr *, int, int, uchar_t *, uchar_t *);
193 static double deltaT(struct timeval *, struct timeval *);
194 static char *device_name(struct ifaddrlist *, int, union any_in_addr *,
195     struct pr_set *);
196 extern void *find_ancillary_data(struct msghdr *, int, int);
197 static boolean_t has_addr(struct addrinfo *, union any_in_addr *);
198 static struct ifaddrlist *find_device(struct ifaddrlist *, int, char *);
199 static struct ifaddrlist *find_ifaddr(struct ifaddrlist *, int,
200     union any_in_addr *, int);
201 static void get_gwaddrs(char **, int, union any_in_addr *,
202     union any_in_addr *, int *, int *);
203 static void get_hostinfo(char *, int, struct addrinfo **);
204 char *inet_name(union any_in_addr *, int);
205 ushort_t in_cksum(ushort_t *, int);
206 extern int ip_hdr_length_v6(ip6_t *, int, uint8_t *);
207 extern char *pr_type(uchar_t);
208 extern char *pr_type6(uchar_t);
209 extern void print_addr(uchar_t *, int, struct sockaddr *);
210 extern void print_addr6(uchar_t *, int, struct sockaddr *);
211 extern boolean_t print_icmp_other(uchar_t, uchar_t);
212 extern boolean_t print_icmp_other6(uchar_t, uchar_t);
213 static void print_stats(int, int, double, double, double, double);
214 static void print_unknown_host_msg(const char *, const char *);
215 static void record_stats(double, int *, double *, double *, double *, double *);
216 static void resolve_nodes(int *, struct addrinfo **);
217 static void select_src_addr(union any_in_addr *, union any_in_addr *, int);
218 extern void send_probe(int, struct sockaddr *, struct ip *, int, int,
219     struct timeval *, int);
220 extern void send_probe6(int, struct msghdr *, struct ip *, int, int,
221     struct timeval *, int);
222 extern void set_ancillary_data(struct msghdr *, int, union any_in_addr *, int,
223     uint_t);
224 extern struct ip *set_buffers(int);
225 extern struct ip *set_buffers6(int);
226 extern void set_IPv4opt_sourcerouting(int, union any_in_addr *,
227     union any_in_addr *);
228 static void set_sin(struct sockaddr *, union any_in_addr *, int);
229 static int set_src_addr(struct pr_set *, struct ifaddrlist **);
230 static void setup_protocol(struct pr_set *, int);
231 static void setup_socket(struct pr_set *, int);
232 static void sig_handler(int);
233 static int str2int(const char *, const char *, int, int);
234 static double str2dbl(const char *, const char *, double, double);
235 static void trace_it(struct addrinfo *);
236 static void traceroute(union any_in_addr *, struct msghdr *, struct pr_set *,
237     int, struct ifaddrlist *);
238 static void tv_sub(struct timeval *, struct timeval *);
239 static void usage(void);
240 static int wait_for_reply(int, struct msghdr *, struct timeval *);
241 static double xsqrt(double);
242 
243 /*
244  * main
245  */
246 int
247 main(int argc, char **argv)
248 {
249 	struct addrinfo *ai_dst = NULL;		/* destination host */
250 	/*
251 	 * "probing_successful" indicates if we could successfully send probes,
252 	 * not necessarily received reply from the target (this behavior is from
253 	 * the original traceroute). It's _B_FALSE if packlen is invalid, or no
254 	 * interfaces found.
255 	 */
256 	boolean_t probing_successful = _B_FALSE;
257 	int longjmp_return;			/* return value from longjump */
258 	int i = 0;
259 	char *cp;
260 	int op;
261 	char *ep;
262 	char temp_buf[INET6_ADDRSTRLEN];	/* use for inet_ntop() */
263 	double pause;
264 
265 	/*
266 	 * A raw socket will be used for IPv4 if there is sufficient
267 	 * privilege.
268 	 */
269 	raw_req = priv_ineffect(PRIV_NET_RAWACCESS);
270 
271 	/*
272 	 * We'll need the privilege only when we open the sockets; that's
273 	 * when we'll fail if the program has insufficient privileges.
274 	 */
275 	(void) __init_suid_priv(PU_CLEARLIMITSET, PRIV_NET_ICMPACCESS,
276 	    raw_req ? PRIV_NET_RAWACCESS : NULL, NULL);
277 
278 	(void) setlinebuf(stdout);
279 
280 	if ((cp = strrchr(argv[0], '/')) != NULL)
281 		prog = cp + 1;
282 	else
283 		prog = argv[0];
284 
285 	opterr = 0;
286 	while ((op = getopt(argc, argv, "adFIlnrSvxA:c:f:g:i:L:m:P:p:Q:q:s:"
287 	    "t:w:")) != EOF) {
288 		switch (op) {
289 		case 'A':
290 			if (strcmp(optarg, "inet") == 0) {
291 				family_input = AF_INET;
292 			} else if (strcmp(optarg, "inet6") == 0) {
293 				family_input = AF_INET6;
294 			} else {
295 				Fprintf(stderr,
296 				    "%s: unknown address family %s\n",
297 				    prog, optarg);
298 				exit(EXIT_FAILURE);
299 			}
300 			break;
301 
302 		case 'a':
303 			probe_all = _B_TRUE;
304 			break;
305 
306 		case 'c':
307 			class = str2int(optarg, "traffic class", 0,
308 			    MAX_TRAFFIC_CLASS);
309 			break;
310 
311 		case 'd':
312 			options |= SO_DEBUG;
313 			break;
314 
315 		case 'f':
316 			first_ttl = str2int(optarg, "first ttl", 1, MAXTTL);
317 			break;
318 
319 		case 'F':
320 			off = IP_DF;
321 			break;
322 
323 		case 'g':
324 			if (!raw_req) {
325 				Fprintf(stderr,
326 				    "%s: privilege to specify a loose source "
327 				    "route gateway is unavailable\n",
328 				    prog);
329 				exit(EXIT_FAILURE);
330 			}
331 			if (gw_count >= MAXMAX_GWS) {
332 				Fprintf(stderr,
333 				    "%s: Too many gateways\n", prog);
334 				exit(EXIT_FAILURE);
335 			}
336 			gwlist[gw_count] = strdup(optarg);
337 			if (gwlist[gw_count] == NULL) {
338 				Fprintf(stderr, "%s: strdup %s\n", prog,
339 				    strerror(errno));
340 				exit(EXIT_FAILURE);
341 			}
342 
343 			++gw_count;
344 			break;
345 
346 		case 'l':
347 			showttl = _B_TRUE;
348 			break;
349 
350 		case 'i':
351 			/* this can be IF name or IF index */
352 			if_index = (uint_t)strtol(optarg, &ep, 10);
353 
354 			/* convert IF index <-->  IF name */
355 			if (errno != 0 || *ep != '\0') {
356 				device = optarg;
357 				if_index = if_nametoindex((const char *)device);
358 
359 				/*
360 				 * In case it fails, check to see if the problem
361 				 * is other than "IF not found".
362 				 */
363 				if (if_index == 0 && errno != ENXIO) {
364 					Fprintf(stderr, "%s: if_nametoindex:"
365 					    "%s\n", prog, strerror(errno));
366 					exit(EXIT_FAILURE);
367 				}
368 			} else {
369 				device = (char *)malloc(LIFNAMSIZ + 1);
370 				if (device == NULL) {
371 					Fprintf(stderr, "%s: malloc: %s\n",
372 					    prog, strerror(errno));
373 					exit(EXIT_FAILURE);
374 				}
375 
376 				device = if_indextoname(if_index, device);
377 				if (device != NULL) {
378 					device[LIFNAMSIZ] = '\0';
379 				} else if (errno != ENXIO) {
380 					/*
381 					 * The problem was other than "index
382 					 * not found".
383 					 */
384 					Fprintf(stderr, "%s: if_indextoname:"
385 					    "%s\n", prog, strerror(errno));
386 					exit(EXIT_FAILURE);
387 				}
388 			}
389 
390 			if (device == NULL || if_index == 0) {
391 				Fprintf(stderr, "%s: interface %s "
392 				    "doesn't match any actual interfaces\n",
393 				    prog, optarg);
394 				exit(EXIT_FAILURE);
395 			}
396 			break;
397 
398 		case 'I':
399 			useicmp = _B_TRUE;
400 			break;
401 
402 		case 'L':
403 			flow = str2int(optarg, "flow label", 0, MAX_FLOW_LABEL);
404 			break;
405 
406 		case 'm':
407 			max_ttl = str2int(optarg, "max ttl(hop limit)", 1,
408 			    MAXTTL);
409 			break;
410 
411 		case 'n':
412 			nflag = _B_TRUE;
413 			break;
414 
415 		case 'P':
416 			pause = str2dbl(optarg, "pause", 0, INT_MAX);
417 			delay.tv_sec = (time_t)pause;
418 			delay.tv_usec = (suseconds_t)((pause - delay.tv_sec) *
419 			    1000000);
420 			break;
421 
422 		case 'p':
423 			port = str2int(optarg, "port", 1, MAX_PORT);
424 			break;
425 
426 		case 'Q':
427 			max_timeout = str2int(optarg, "max timeout", 1, -1);
428 			break;
429 
430 		case 'q':
431 			nprobes = str2int(optarg, "nprobes", 1, -1);
432 			break;
433 
434 		case 'r':
435 			options |= SO_DONTROUTE;
436 			break;
437 
438 		case 'S':
439 			collect_stat = _B_TRUE;
440 			break;
441 
442 		case 's':
443 			/*
444 			 * set the ip source address of the outbound
445 			 * probe (e.g., on a multi-homed host).
446 			 */
447 			source_input = optarg;
448 			break;
449 
450 		case 't':
451 			tos = (uchar_t)str2int(optarg, "tos", 0, MAX_TOS);
452 			settos = _B_TRUE;
453 			break;
454 
455 		case 'v':
456 			verbose = _B_TRUE;
457 			break;
458 
459 		case 'x':
460 			docksum = _B_FALSE;
461 			break;
462 
463 		case 'w':
464 			waittime = str2int(optarg, "wait time", 2, -1);
465 			break;
466 
467 		default:
468 			usage();
469 			break;
470 		}
471 	}
472 
473 	/*
474 	 * If it's probe_all, SIGQUIT makes traceroute exit(). But we set the
475 	 * address to jump back to in traceroute(). Until then, we'll need to
476 	 * temporarily specify one.
477 	 */
478 	if (probe_all) {
479 		if ((longjmp_return = setjmp(env)) != 0) {
480 			if (longjmp_return == SIGQUIT) {
481 				Printf("(exiting)\n");
482 				exit(EXIT_SUCCESS);
483 			} else {		/* should never happen */
484 				exit(EXIT_FAILURE);
485 			}
486 		}
487 		(void) signal(SIGQUIT, sig_handler);
488 	}
489 
490 	if ((gw_count > 0) && (options & SO_DONTROUTE)) {
491 		Fprintf(stderr, "%s: loose source route gateways (-g)"
492 		    " cannot be specified when probe packets are sent"
493 		    " directly to a host on an attached network (-r)\n",
494 		    prog);
495 		exit(EXIT_FAILURE);
496 	}
497 
498 	i = argc - optind;
499 	if (i == 1 || i == 2) {
500 		hostname = argv[optind];
501 
502 		if (i == 2) {
503 			/* accept any length now, we'll check it later */
504 			packlen_input = str2int(argv[optind + 1],
505 			    "packet length", 0, -1);
506 		}
507 	} else {
508 		usage();
509 	}
510 
511 	if (first_ttl > max_ttl) {
512 		Fprintf(stderr,
513 		    "%s: first ttl(hop limit) (%d) may not be greater"
514 		    " than max ttl(hop limit) (%d)\n",
515 		    prog, first_ttl, max_ttl);
516 		exit(EXIT_FAILURE);
517 	}
518 
519 	/* resolve hostnames */
520 	resolve_nodes(&family_input, &ai_dst);
521 	if (ai_dst == NULL) {
522 		exit(EXIT_FAILURE);
523 	}
524 
525 	/*
526 	 * If it's probe_all, SIGINT makes traceroute skip to probing next IP
527 	 * address of the target. The new interrupt handler is assigned in
528 	 * traceroute() function. Until then let's ignore the signal.
529 	 */
530 	if (probe_all)
531 		(void) signal(SIGINT, SIG_IGN);
532 
533 	ident = (getpid() & 0xffff) | 0x8000;
534 
535 	/*
536 	 * We KNOW that probe_all == TRUE if family is AF_UNSPEC,
537 	 * since family is set to the specific AF found unless it's
538 	 * probe_all. So if family == AF_UNSPEC, we need to init pr4 and pr6.
539 	 */
540 	switch (family_input) {
541 	case AF_UNSPEC:
542 		pr4 = (struct pr_set *)malloc(sizeof (struct pr_set));
543 		if (pr4 == NULL) {
544 			Fprintf(stderr,
545 			    "%s: malloc %s\n", prog, strerror(errno));
546 			exit(EXIT_FAILURE);
547 		}
548 		pr6 = (struct pr_set *)malloc(sizeof (struct pr_set));
549 		if (pr6 == NULL) {
550 			Fprintf(stderr,
551 			    "%s: malloc %s\n", prog, strerror(errno));
552 			exit(EXIT_FAILURE);
553 		}
554 		setup_protocol(pr6, AF_INET6);
555 		setup_protocol(pr4, AF_INET);
556 		outip6 = (*pr6->set_buffers_fn)(pr6->packlen);
557 		setup_socket(pr6, pr6->packlen);
558 
559 		outip4 = (*pr4->set_buffers_fn)(pr4->packlen);
560 		setup_socket(pr4, pr4->packlen);
561 		num_ifs6 = set_src_addr(pr6, &al6);
562 		num_ifs4 = set_src_addr(pr4, &al4);
563 		break;
564 	case AF_INET6:
565 		pr6 = (struct pr_set *)malloc(sizeof (struct pr_set));
566 		if (pr6 == NULL) {
567 			Fprintf(stderr,
568 			    "%s: malloc %s\n", prog, strerror(errno));
569 			exit(EXIT_FAILURE);
570 		}
571 		setup_protocol(pr6, AF_INET6);
572 		outip6 = (*pr6->set_buffers_fn)(pr6->packlen);
573 		setup_socket(pr6, pr6->packlen);
574 		num_ifs6 = set_src_addr(pr6, &al6);
575 		break;
576 	case AF_INET:
577 		pr4 = (struct pr_set *)malloc(sizeof (struct pr_set));
578 		if (pr4 == NULL) {
579 			Fprintf(stderr,
580 			    "%s: malloc %s\n", prog, strerror(errno));
581 			exit(EXIT_FAILURE);
582 		}
583 		setup_protocol(pr4, AF_INET);
584 		outip4 = (*pr4->set_buffers_fn)(pr4->packlen);
585 		setup_socket(pr4, pr4->packlen);
586 		num_ifs4 = set_src_addr(pr4, &al4);
587 		break;
588 	default:
589 		Fprintf(stderr, "%s: unknow address family.\n", prog);
590 		exit(EXIT_FAILURE);
591 	}
592 
593 	if (num_v4 + num_v6 > 1 && !probe_all) {
594 		if (ai_dst->ai_family == AF_INET) {
595 			Fprintf(stderr,
596 			    "%s: Warning: %s has multiple addresses;"
597 			    " using %s\n", prog, hostname,
598 			    inet_ntop(AF_INET,
599 			    /* LINTED E_BAD_PTR_CAST_ALIGN */
600 			    (void *)&((struct sockaddr_in *)
601 			    ai_dst->ai_addr)->sin_addr,
602 			    temp_buf, sizeof (temp_buf)));
603 		} else {
604 			Fprintf(stderr,
605 			    "%s: Warning: %s has multiple addresses;"
606 			    " using %s\n", prog, hostname,
607 			    inet_ntop(AF_INET6,
608 			    /* LINTED E_BAD_PTR_CAST_ALIGN */
609 			    (void *)&((struct sockaddr_in6 *)
610 			    ai_dst->ai_addr)->sin6_addr,
611 			    temp_buf, sizeof (temp_buf)));
612 		}
613 	}
614 
615 	if (num_ifs4 + num_ifs6 > 0) {
616 		trace_it(ai_dst);
617 		probing_successful = _B_TRUE;
618 	}
619 
620 	(void) close(rcvsock4);
621 	(void) close(sndsock4);
622 	(void) close(rcvsock6);
623 	(void) close(sndsock6);
624 
625 	/*
626 	 * if we could probe any of the IP addresses of the target, that means
627 	 * this was a successful operation
628 	 */
629 	if (probing_successful)
630 		return (EXIT_SUCCESS);
631 	else
632 		return (EXIT_FAILURE);
633 }
634 
635 /*
636  * print "unknown host" message
637  */
638 static void
639 print_unknown_host_msg(const char *protocol, const char *host)
640 {
641 	Fprintf(stderr, "%s: unknown%s host %s\n", prog, protocol, host);
642 }
643 
644 /*
645  * resolve destination host and gateways
646  */
647 static void
648 resolve_nodes(int *family, struct addrinfo **ai_dstp)
649 {
650 	struct addrinfo *ai_dst = NULL;
651 	struct addrinfo *aip = NULL;
652 	int num_resolved_gw = 0;
653 	int num_resolved_gw6 = 0;
654 
655 	get_hostinfo(hostname, *family, &ai_dst);
656 	if (ai_dst == NULL) {
657 		print_unknown_host_msg("", hostname);
658 		exit(EXIT_FAILURE);
659 	}
660 	/* Get a count of the v4 & v6 addresses */
661 	for (aip = ai_dst; aip != NULL; aip = aip->ai_next) {
662 		switch (aip->ai_family) {
663 		case AF_INET:
664 			num_v4++;
665 			break;
666 		case AF_INET6:
667 			num_v6++;
668 			break;
669 		}
670 	}
671 
672 	if (*family == AF_UNSPEC && !probe_all) {
673 		*family = ai_dst->ai_family;
674 	}
675 
676 	/* resolve gateways */
677 	if (gw_count > 0) {
678 		get_gwaddrs(gwlist, *family, gwIPlist, gwIP6list,
679 		    &num_resolved_gw, &num_resolved_gw6);
680 
681 		/* we couldn't resolve a gateway as an IPv6 host */
682 		if (num_resolved_gw6 != gw_count && num_v6 != 0) {
683 			if (*family == AF_INET6 || *family == AF_UNSPEC)
684 				print_unknown_host_msg(" IPv6",
685 				    gwlist[num_resolved_gw6]);
686 			num_v6 = 0;
687 		}
688 
689 		/* we couldn't resolve a gateway as an IPv4 host */
690 		if (num_resolved_gw != gw_count && num_v4 != 0) {
691 			if (*family == AF_INET || *family == AF_UNSPEC)
692 				print_unknown_host_msg(" IPv4",
693 				    gwlist[num_resolved_gw]);
694 			num_v4 = 0;
695 		}
696 	}
697 
698 	*ai_dstp = (num_v4 + num_v6 > 0) ? ai_dst : NULL;
699 }
700 
701 /*
702  * Given IP address or hostname, return v4 and v6 hostinfo lists.
703  * Assumes that hostinfo ** ptrs are non-null.
704  */
705 static void
706 get_hostinfo(char *host, int family, struct addrinfo **aipp)
707 {
708 	struct addrinfo hints, *ai;
709 	struct in6_addr addr6;
710 	struct in_addr addr;
711 	char temp_buf[INET6_ADDRSTRLEN];	/* use for inet_ntop() */
712 	int rc;
713 
714 	/*
715 	 * Take care of v4-mapped addresses. It should run same as v4, after
716 	 * chopping off the prefix, leaving the IPv4 address
717 	 */
718 	if ((inet_pton(AF_INET6, host, &addr6) > 0) &&
719 	    IN6_IS_ADDR_V4MAPPED(&addr6)) {
720 		/* peel off the "mapping" stuff, leaving 32 bit IPv4 address */
721 		IN6_V4MAPPED_TO_INADDR(&addr6, &addr);
722 
723 		/* convert it back to a string */
724 		(void) inet_ntop(AF_INET, (void *)&addr, temp_buf,
725 		    sizeof (temp_buf));
726 
727 		/* now the host is an IPv4 address */
728 		(void) strcpy(host, temp_buf);
729 
730 		/*
731 		 * If it's a mapped address, we convert it into IPv4
732 		 * address because traceroute will send and receive IPv4
733 		 * packets for that address. Therefore, it's a failure case to
734 		 * ask get_hostinfo() to treat a mapped address as an IPv6
735 		 * address.
736 		 */
737 		if (family == AF_INET6) {
738 			return;
739 		}
740 	}
741 
742 	(void) memset(&hints, 0, sizeof (hints));
743 	hints.ai_family = family;
744 	hints.ai_flags = AI_ADDRCONFIG | AI_CANONNAME;
745 	rc = getaddrinfo(host, NULL, &hints, &ai);
746 	if (rc != 0) {
747 		if (rc != EAI_NONAME)
748 			Fprintf(stderr, "%s: getaddrinfo: %s\n", prog,
749 			    gai_strerror(rc));
750 		*aipp = NULL;
751 		return;
752 	}
753 	*aipp = ai;
754 }
755 
756 /*
757  * Calculate the packet length to be used, and check against the valid range.
758  * Returns -1 if range check fails.
759  */
760 static uint_t
761 calc_packetlen(int plen_input, struct pr_set *pr)
762 {
763 	int minpacket;			/* min ip packet size */
764 	int optlen;			/* length of ip options */
765 	int plen;
766 
767 	/*
768 	 * LBNL bug fixed: miscalculation of optlen
769 	 */
770 	if (gw_count > 0) {
771 		/*
772 		 * IPv4:
773 		 * ----
774 		 * 5 (NO OPs) + 3 (code, len, ptr) + gateways
775 		 * IP options field can hold up to 9 gateways. But the API
776 		 * allows you to specify only 8, because the last one is the
777 		 * destination host. When this packet is sent, on the wire
778 		 * you see one gateway replaced by 4 NO OPs. The other 1 NO
779 		 * OP is for alignment
780 		 *
781 		 * IPv6:
782 		 * ----
783 		 * Well, formula is different, but the result is same.
784 		 * 8 byte fixed part for Type 0 Routing header, followed by
785 		 * gateway addresses
786 		 */
787 		optlen = 8 + gw_count * pr->addr_len;
788 	} else {
789 		optlen = 0;
790 	}
791 
792 	/* take care of the packet length calculations and checks */
793 	minpacket = pr->ip_hdr_len + sizeof (struct outdata) + optlen;
794 	if (useicmp)
795 		minpacket += pr->icmp_minlen;	/* minimum ICMP header size */
796 	else
797 		minpacket += sizeof (struct udphdr);
798 	plen = plen_input;
799 	if (plen == 0) {
800 		plen = minpacket;		/* minimum sized packet */
801 	} else if (minpacket > plen || plen > IP_MAXPACKET) {
802 		Fprintf(stderr, "%s: %s packet size must be >= %d and <= %d\n",
803 		    prog, pr->name, minpacket, IP_MAXPACKET);
804 		return (0);
805 	}
806 
807 	return (plen);
808 }
809 
810 /*
811  * Sets the source address by resolving -i and -s arguments, or if -i and -s
812  * don't dictate any, it sets the pick_src to make sure traceroute uses the
813  * kernel's pick of the source address.
814  * Returns number of interfaces configured on the source host, 0 on error or
815  * there's no interface which is up amd not a loopback.
816  */
817 static int
818 set_src_addr(struct pr_set *pr, struct ifaddrlist **alp)
819 {
820 	union any_in_addr *ap;
821 	struct ifaddrlist *al = NULL;
822 	struct ifaddrlist *tmp1_al = NULL;
823 	struct ifaddrlist *tmp2_al = NULL;
824 	/* LINTED E_BAD_PTR_CAST_ALIGN */
825 	struct sockaddr_in *sin_from = (struct sockaddr_in *)pr->from;
826 	/* LINTED E_BAD_PTR_CAST_ALIGN */
827 	struct sockaddr_in6 *sin6_from = (struct sockaddr_in6 *)pr->from;
828 	struct addrinfo *aip;
829 	char errbuf[ERRBUFSIZE];
830 	char temp_buf[INET6_ADDRSTRLEN];	/* use for inet_ntop() */
831 	int num_ifs;				/* all the interfaces  */
832 	int num_src_ifs;			/* exclude loopback and down */
833 	int i;
834 
835 	source = source_input;
836 
837 	/* get the interface address list */
838 	num_ifs = ifaddrlist(&al, pr->family, errbuf);
839 	if (num_ifs < 0) {
840 		Fprintf(stderr, "%s: ifaddrlist: %s\n", prog, errbuf);
841 		exit(EXIT_FAILURE);
842 	}
843 
844 	num_src_ifs = 0;
845 	for (i = 0; i < num_ifs; i++) {
846 		if (!(al[i].flags & IFF_LOOPBACK) && (al[i].flags & IFF_UP))
847 			num_src_ifs++;
848 	}
849 
850 	if (num_src_ifs == 0) {
851 		Fprintf(stderr, "%s: can't find any %s network interfaces\n",
852 		    prog, pr->name);
853 		return (0);
854 	}
855 
856 	/* verify the device */
857 	if (device != NULL) {
858 		tmp1_al = find_device(al, num_ifs, device);
859 
860 		if (tmp1_al == NULL) {
861 			Fprintf(stderr, "%s: %s (index %d) is an invalid %s"
862 			    " interface\n", prog, device, if_index, pr->name);
863 			free(al);
864 			return (0);
865 		}
866 	}
867 
868 	/* verify the source address */
869 	if (source != NULL) {
870 		get_hostinfo(source, pr->family, &aip);
871 		if (aip == NULL) {
872 			Fprintf(stderr,
873 			    "%s: %s is an invalid %s source address\n",
874 			    prog, source, pr->name);
875 
876 			free(al);
877 			return (0);
878 		}
879 
880 		source = aip->ai_canonname;
881 
882 		if (pr->family == AF_INET)
883 			ap = (union any_in_addr *)
884 			    /* LINTED E_BAD_PTR_CAST_ALIGN */
885 			    &((struct sockaddr_in *)
886 				aip->ai_addr)->sin_addr;
887 		else
888 			ap = (union any_in_addr *)
889 			    /* LINTED E_BAD_PTR_CAST_ALIGN */
890 			    &((struct sockaddr_in6 *)
891 				aip->ai_addr)->sin6_addr;
892 
893 		/*
894 		 * LBNL bug fixed: used to accept any src address
895 		 */
896 		tmp2_al = find_ifaddr(al, num_ifs, ap, pr->family);
897 
898 		if (tmp2_al == NULL) {
899 			Fprintf(stderr,
900 			    "%s: %s is not a local %s address\n",
901 			    prog, inet_ntop(pr->family, ap,
902 				temp_buf, sizeof (temp_buf)),
903 			    pr->name);
904 
905 			free(al);
906 			freeaddrinfo(aip);
907 			return (0);
908 		}
909 	}
910 
911 	pick_src = _B_FALSE;
912 
913 	if (source == NULL) {			/* no -s used */
914 		if (device == NULL) {		/* no -i used, no -s used */
915 			pick_src = _B_TRUE;
916 		} else {			/* -i used, no -s used */
917 			/*
918 			 * -i used, but not -s, and it's IPv4: set the source
919 			 * address to whatever the interface has configured on
920 			 * it.
921 			 */
922 			if (pr->family == AF_INET)
923 				set_sin(pr->from, &(tmp1_al->addr), pr->family);
924 			else
925 				pick_src = _B_TRUE;
926 		}
927 	} else {				/* -s used */
928 		if (device == NULL) {		/* no -i used, -s used */
929 			set_sin(pr->from, ap, pr->family);
930 
931 			if (aip->ai_next != NULL) {
932 				Fprintf(stderr,
933 				    "%s: Warning: %s has multiple "
934 				    "addresses; using %s\n",
935 				    prog, source,
936 				    inet_ntop(pr->family,
937 					(const void *)pr->from_sin_addr,
938 					temp_buf, sizeof (temp_buf)));
939 			}
940 		} else {			/* -i and -s used */
941 			/*
942 			 * Make sure the source specified matches the
943 			 * interface address. You only care about this for IPv4
944 			 * IPv6 can handle IF not matching src address
945 			 */
946 			if (pr->family == AF_INET) {
947 				if (!has_addr(aip, &tmp1_al->addr)) {
948 					Fprintf(stderr,
949 					    "%s: %s is not on interface %s\n",
950 					    prog, source, device);
951 					exit(EXIT_FAILURE);
952 				}
953 				/*
954 				 * make sure we use the one matching the
955 				 * interface's address
956 				 */
957 				*ap = tmp1_al->addr;
958 			}
959 
960 			set_sin(pr->from, ap, pr->family);
961 		}
962 	}
963 
964 	/*
965 	 * Binding at this point will set the source address to be used
966 	 * for both IPv4 (when raw IP datagrams are not required) and
967 	 * IPv6.  If the address being bound to is zero, then the kernel
968 	 * will end up choosing the source address when the datagram is
969 	 * sent.
970 	 *
971 	 * For raw IPv4 datagrams, the source address is initialized
972 	 * within traceroute() along with the outbound destination
973 	 * address.
974 	 */
975 	if (pr->family == AF_INET && !raw_req) {
976 		sin_from->sin_family = AF_INET;
977 		sin_from->sin_port = htons(ident);
978 		if (bind(sndsock4, (struct sockaddr *)pr->from,
979 			sizeof (struct sockaddr_in)) < 0) {
980 			Fprintf(stderr, "%s: bind: %s\n", prog,
981 			    strerror(errno));
982 			exit(EXIT_FAILURE);
983 		}
984 	} else if (pr->family == AF_INET6) {
985 		sin6_from->sin6_family = AF_INET6;
986 		sin6_from->sin6_port = htons(ident);
987 		if (bind(sndsock6, (struct sockaddr *)pr->from,
988 			sizeof (struct sockaddr_in6)) < 0) {
989 			Fprintf(stderr, "%s: bind: %s\n", prog,
990 			    strerror(errno));
991 			exit(EXIT_FAILURE);
992 		}
993 
994 		whereto6.sin6_flowinfo = htonl((class << 20) | flow);
995 	}
996 	*alp = al;
997 	return (num_ifs);
998 }
999 
1000 /*
1001  * Returns the complete ifaddrlist structure matching the desired interface
1002  * address. Ignores interfaces which are either down or loopback.
1003  */
1004 static struct ifaddrlist *
1005 find_ifaddr(struct ifaddrlist *al, int len, union any_in_addr *addr,
1006     int family)
1007 {
1008 	struct ifaddrlist *tmp_al = al;
1009 	int i;
1010 	size_t addr_len = (family == AF_INET) ? sizeof (struct in_addr) :
1011 	    sizeof (struct in6_addr);
1012 
1013 	for (i = 0; i < len; i++, tmp_al++) {
1014 		if ((!(tmp_al->flags & IFF_LOOPBACK) &&
1015 		    (tmp_al->flags & IFF_UP)) &&
1016 		    (memcmp(&tmp_al->addr, addr, addr_len) == 0))
1017 			break;
1018 	}
1019 
1020 	if (i < len) {
1021 		return (tmp_al);
1022 	} else {
1023 		return (NULL);
1024 	}
1025 }
1026 
1027 /*
1028  * Returns the complete ifaddrlist structure matching the desired interface name
1029  * Ignores interfaces which are either down or loopback.
1030  */
1031 static struct ifaddrlist *
1032 find_device(struct ifaddrlist *al, int len, char *device)
1033 {
1034 	struct ifaddrlist *tmp_al = al;
1035 	int i;
1036 
1037 	for (i = 0; i < len; i++, tmp_al++) {
1038 		if ((!(tmp_al->flags & IFF_LOOPBACK) &&
1039 		    (tmp_al->flags & IFF_UP)) &&
1040 		    (strcmp(tmp_al->device, device) == 0))
1041 			break;
1042 	}
1043 
1044 	if (i < len) {
1045 		return (tmp_al);
1046 	} else {
1047 		return (NULL);
1048 	}
1049 }
1050 
1051 /*
1052  * returns _B_TRUE if given hostinfo contains the given address
1053  */
1054 static boolean_t
1055 has_addr(struct addrinfo *ai, union any_in_addr *addr)
1056 {
1057 	struct addrinfo *ai_tmp = NULL;
1058 	union any_in_addr *ap;
1059 
1060 	for (ai_tmp = ai; ai_tmp != NULL; ai_tmp = ai_tmp->ai_next) {
1061 		if (ai_tmp->ai_family == AF_INET6)
1062 			continue;
1063 		ap = (union any_in_addr *)
1064 		    /* LINTED E_BAD_PTR_CAST_ALIGN */
1065 		    &((struct sockaddr_in *)ai_tmp->ai_addr)->sin_addr;
1066 		if (memcmp(ap, addr, sizeof (struct in_addr)) == 0)
1067 			break;
1068 	}
1069 
1070 	if (ai_tmp != NULL) {
1071 		return (_B_TRUE);
1072 	} else {
1073 		return (_B_FALSE);
1074 	}
1075 }
1076 
1077 /*
1078  * Resolve the gateway names, splitting results into v4 and v6 lists.
1079  * Gateway addresses are added to the appropriate passed-in array; the
1080  * number of resolved gateways for each af is returned in resolved[6].
1081  * Assumes that passed-in arrays are large enough for MAX_GWS[6] addrs
1082  * and resolved[6] ptrs are non-null; ignores array and counter if the
1083  * address family param makes them irrelevant.
1084  */
1085 static void
1086 get_gwaddrs(char **gwlist, int family, union any_in_addr *gwIPlist,
1087     union any_in_addr *gwIPlist6, int *resolved, int *resolved6)
1088 {
1089 	int i;
1090 	boolean_t check_v4 = _B_TRUE, check_v6 = _B_TRUE;
1091 	struct addrinfo *ai = NULL;
1092 	struct addrinfo *aip = NULL;
1093 
1094 	*resolved = *resolved6 = 0;
1095 	switch (family) {
1096 	case AF_UNSPEC:
1097 		break;
1098 	case AF_INET:
1099 		check_v6 = _B_FALSE;
1100 		break;
1101 	case AF_INET6:
1102 		check_v4 = _B_FALSE;
1103 		break;
1104 	default:
1105 		return;
1106 	}
1107 
1108 	if (check_v4 && gw_count >= MAX_GWS) {
1109 		check_v4 = _B_FALSE;
1110 		Fprintf(stderr, "%s: too many IPv4 gateways\n", prog);
1111 		num_v4 = 0;
1112 	}
1113 	if (check_v6 && gw_count >= MAX_GWS6) {
1114 		check_v6 = _B_FALSE;
1115 		Fprintf(stderr, "%s: too many IPv6 gateways\n", prog);
1116 		num_v6 = 0;
1117 	}
1118 
1119 	for (i = 0; i < gw_count; i++) {
1120 		if (!check_v4 && !check_v6)
1121 			return;
1122 		get_hostinfo(gwlist[i], family, &ai);
1123 		if (ai == NULL)
1124 			return;
1125 		if (check_v4 && num_v4 != 0) {
1126 			check_v4 = _B_FALSE;
1127 			for (aip = ai; aip != NULL; aip = aip->ai_next) {
1128 				if (aip->ai_family == AF_INET) {
1129 					/* LINTED E_BAD_PTR_CAST_ALIGN */
1130 					bcopy(&((struct sockaddr_in *)
1131 					    aip->ai_addr)->sin_addr,
1132 					    &gwIPlist[i].addr,
1133 					    aip->ai_addrlen);
1134 					(*resolved)++;
1135 					check_v4 = _B_TRUE;
1136 					break;
1137 				}
1138 			}
1139 		} else if (check_v4) {
1140 			check_v4 = _B_FALSE;
1141 		}
1142 		if (check_v6 && num_v6 != 0) {
1143 			check_v6 = _B_FALSE;
1144 			for (aip = ai; aip != NULL; aip = aip->ai_next) {
1145 				if (aip->ai_family == AF_INET6) {
1146 					/* LINTED E_BAD_PTR_CAST_ALIGN */
1147 					bcopy(&((struct sockaddr_in6 *)
1148 					    aip->ai_addr)->sin6_addr,
1149 					    &gwIPlist6[i].addr6,
1150 					    aip->ai_addrlen);
1151 					(*resolved6)++;
1152 					check_v6 = _B_TRUE;
1153 					break;
1154 				}
1155 			}
1156 		} else if (check_v6) {
1157 			check_v6 = _B_FALSE;
1158 		}
1159 	}
1160 	freeaddrinfo(ai);
1161 }
1162 
1163 /*
1164  * set protocol specific values here
1165  */
1166 static void
1167 setup_protocol(struct pr_set *pr, int family)
1168 {
1169 	/*
1170 	 * Set the global variables for each AF. This is going to save us lots
1171 	 * of "if (family == AF_INET)... else .."
1172 	 */
1173 	pr->family = family;
1174 
1175 	if (family == AF_INET) {
1176 		if (!docksum) {
1177 			Fprintf(stderr,
1178 			    "%s: Warning: checksums disabled\n", prog);
1179 		}
1180 		(void) strcpy(pr->name, "IPv4");
1181 		(void) strcpy(pr->icmp, "icmp");
1182 		pr->icmp_minlen = ICMP_MINLEN;
1183 		pr->addr_len = sizeof (struct in_addr);
1184 		pr->ip_hdr_len = sizeof (struct ip);
1185 		pr->sock_size = sizeof (struct sockaddr_in);
1186 		pr->to = (struct sockaddr *)&whereto;
1187 		pr->from = (struct sockaddr *)&wherefrom;
1188 		pr->from_sin_addr = (void *)&wherefrom.sin_addr;
1189 		pr->gwIPlist = gwIPlist;
1190 		pr->set_buffers_fn = set_buffers;
1191 		pr->check_reply_fn = check_reply;
1192 		pr->print_icmp_other_fn = print_icmp_other;
1193 		pr->print_addr_fn = print_addr;
1194 		pr->packlen = calc_packetlen(packlen_input, pr);
1195 	} else {
1196 		(void) strcpy(pr->name, "IPv6");
1197 		(void) strcpy(pr->icmp, "ipv6-icmp");
1198 		pr->icmp_minlen = ICMP6_MINLEN;
1199 		pr->addr_len = sizeof (struct in6_addr);
1200 		pr->ip_hdr_len = sizeof (struct ip6_hdr);
1201 		pr->sock_size = sizeof (struct sockaddr_in6);
1202 		pr->to = (struct sockaddr *)&whereto6;
1203 		pr->from = (struct sockaddr *)&wherefrom6;
1204 		pr->from_sin_addr = (void *)&wherefrom6.sin6_addr;
1205 		pr->gwIPlist = gwIP6list;
1206 		pr->set_buffers_fn = set_buffers6;
1207 		pr->check_reply_fn = check_reply6;
1208 		pr->print_icmp_other_fn = print_icmp_other6;
1209 		pr->print_addr_fn = print_addr6;
1210 		pr->packlen = calc_packetlen(packlen_input, pr);
1211 	}
1212 	if (pr->packlen == 0)
1213 		exit(EXIT_FAILURE);
1214 }
1215 
1216 /*
1217  * setup the sockets for the given protocol's address family
1218  */
1219 static void
1220 setup_socket(struct pr_set *pr, int packet_len)
1221 {
1222 	int on = 1;
1223 	struct protoent *pe;
1224 	int type;
1225 	int proto;
1226 	int int_op;
1227 	int rsock;
1228 	int ssock;
1229 
1230 	if ((pe = getprotobyname(pr->icmp)) == NULL) {
1231 		Fprintf(stderr, "%s: unknown protocol %s\n", prog, pr->icmp);
1232 		exit(EXIT_FAILURE);
1233 	}
1234 
1235 	/* privilege bracketing */
1236 	(void) __priv_bracket(PRIV_ON);
1237 
1238 	if ((rsock = socket(pr->family, SOCK_RAW, pe->p_proto)) < 0) {
1239 		Fprintf(stderr, "%s: icmp socket: %s\n", prog, strerror(errno));
1240 		exit(EXIT_FAILURE);
1241 	}
1242 
1243 	if (options & SO_DEBUG) {
1244 		if (setsockopt(rsock, SOL_SOCKET, SO_DEBUG, (char *)&on,
1245 		    sizeof (on)) < 0) {
1246 			Fprintf(stderr, "%s: SO_DEBUG: %s\n", prog,
1247 			    strerror(errno));
1248 			exit(EXIT_FAILURE);
1249 		}
1250 	}
1251 	if (options & SO_DONTROUTE) {
1252 		if (setsockopt(rsock, SOL_SOCKET, SO_DONTROUTE, (char *)&on,
1253 		    sizeof (on)) < 0) {
1254 			Fprintf(stderr, "%s: SO_DONTROUTE: %s\n", prog,
1255 			    strerror(errno));
1256 			exit(EXIT_FAILURE);
1257 		}
1258 	}
1259 
1260 	if (pr->family == AF_INET6) {
1261 		/* Enable receipt of destination address info */
1262 		if (setsockopt(rsock, IPPROTO_IPV6, IPV6_RECVPKTINFO,
1263 		    (char *)&on, sizeof (on)) < 0) {
1264 			Fprintf(stderr, "%s: IPV6_RECVPKTINFO: %s\n", prog,
1265 			    strerror(errno));
1266 			exit(EXIT_FAILURE);
1267 		}
1268 		/* Enable receipt of hoplimit info */
1269 		if (setsockopt(rsock, IPPROTO_IPV6, IPV6_RECVHOPLIMIT,
1270 		    (char *)&on, sizeof (on)) < 0) {
1271 			Fprintf(stderr, "%s: IPV6_RECVHOPLIMIT: %s\n", prog,
1272 			    strerror(errno));
1273 			exit(EXIT_FAILURE);
1274 		}
1275 
1276 	}
1277 
1278 	/*
1279 	 * Initialize the socket type and protocol based on the address
1280 	 * family, whether or not a raw IP socket is required (for IPv4)
1281 	 * or whether ICMP will be used instead of UDP.
1282 	 *
1283 	 * For historical reasons, the datagrams sent out by
1284 	 * traceroute(1M) do not have the "don't fragment" flag set.  For
1285 	 * this reason as well as the ability to set the Loose Source and
1286 	 * Record Route (LSRR) option, a raw IP socket will be used for
1287 	 * IPv4 when run in the global zone.  Otherwise, the actual
1288 	 * datagram that will be sent will be a regular UDP or ICMP echo
1289 	 * request packet.  However for convenience and for future options
1290 	 * when other IP header information may be specified using
1291 	 * traceroute, the buffer including the raw IP and UDP or ICMP
1292 	 * header is always filled in.  When the probe is actually sent,
1293 	 * the size of the request and the start of the packet is set
1294 	 * according to the type of datagram to send.
1295 	 */
1296 	if (pr->family == AF_INET && raw_req) {
1297 		type = SOCK_RAW;
1298 		proto = IPPROTO_RAW;
1299 	} else if (useicmp) {
1300 		type = SOCK_RAW;
1301 		if (pr->family == AF_INET)
1302 			proto = IPPROTO_ICMP;
1303 		else
1304 			proto = IPPROTO_ICMPV6;
1305 	} else {
1306 		type = SOCK_DGRAM;
1307 		proto = IPPROTO_UDP;
1308 	}
1309 	ssock = socket(pr->family, type, proto);
1310 
1311 	if (ssock < 0) {
1312 		if (proto == IPPROTO_RAW) {
1313 			Fprintf(stderr, "%s: raw socket: %s\n", prog,
1314 			    strerror(errno));
1315 		} else if (proto == IPPROTO_UDP) {
1316 			Fprintf(stderr, "%s: udp socket: %s\n", prog,
1317 			    strerror(errno));
1318 		} else {
1319 			Fprintf(stderr, "%s: icmp socket: %s\n", prog,
1320 			    strerror(errno));
1321 		}
1322 		exit(EXIT_FAILURE);
1323 	}
1324 
1325 	if (setsockopt(ssock, SOL_SOCKET, SO_SNDBUF, (char *)&packet_len,
1326 	    sizeof (packet_len)) < 0) {
1327 		Fprintf(stderr, "%s: SO_SNDBUF: %s\n", prog, strerror(errno));
1328 		exit(EXIT_FAILURE);
1329 	}
1330 
1331 	if (pr->family == AF_INET && raw_req) {
1332 		if (setsockopt(ssock, IPPROTO_IP, IP_HDRINCL, (char *)&on,
1333 		    sizeof (on)) < 0) {
1334 			Fprintf(stderr, "%s: IP_HDRINCL: %s\n", prog,
1335 			    strerror(errno));
1336 			exit(EXIT_FAILURE);
1337 		}
1338 	}
1339 
1340 	if (options & SO_DEBUG) {
1341 		if (setsockopt(ssock, SOL_SOCKET, SO_DEBUG, (char *)&on,
1342 		    sizeof (on)) < 0) {
1343 			Fprintf(stderr, "%s: SO_DEBUG: %s\n", prog,
1344 			    strerror(errno));
1345 			exit(EXIT_FAILURE);
1346 		}
1347 	}
1348 	if (options & SO_DONTROUTE) {
1349 		if (setsockopt(ssock, SOL_SOCKET, SO_DONTROUTE,
1350 		    (char *)&on, sizeof (on)) < 0) {
1351 			Fprintf(stderr, "%s: SO_DONTROUTE: %s\n", prog,
1352 			    strerror(errno));
1353 			exit(EXIT_FAILURE);
1354 		}
1355 	}
1356 
1357 	/*
1358 	 * If a raw IPv4 packet is going to be sent, the Type of Service
1359 	 * field in the packet will be initialized in set_buffers().
1360 	 * Otherwise, it is initialized here using the IPPROTO_IP level
1361 	 * socket option.
1362 	 */
1363 	if (settos && !raw_req) {
1364 		int_op = tos;
1365 		if (setsockopt(ssock, IPPROTO_IP, IP_TOS, (char *)&int_op,
1366 		    sizeof (int_op)) < 0) {
1367 			Fprintf(stderr, "%s: IP_TOS: %s\n", prog,
1368 			    strerror(errno));
1369 			exit(EXIT_FAILURE);
1370 		}
1371 	}
1372 	if (pr->family == AF_INET) {
1373 		rcvsock4 = rsock;
1374 		sndsock4 = ssock;
1375 	} else {
1376 		rcvsock6 = rsock;
1377 		sndsock6 = ssock;
1378 	}
1379 	/* Revert to non-privileged user after configuring sockets */
1380 	(void) __priv_bracket(PRIV_OFF);
1381 }
1382 
1383 /*
1384  * If we are "probing all", this function calls traceroute() for each IP address
1385  * of the target, otherwise calls only once. Returns _B_FALSE if traceroute()
1386  * fails.
1387  */
1388 static void
1389 trace_it(struct addrinfo *ai_dst)
1390 {
1391 	struct msghdr msg6;
1392 	int num_dst_IPaddrs;
1393 	struct addrinfo *aip;
1394 	int i;
1395 
1396 	if (!probe_all)
1397 		num_dst_IPaddrs = 1;
1398 	else
1399 		num_dst_IPaddrs = num_v4 + num_v6;
1400 
1401 	/*
1402 	 * Initialize the msg6 structure using the hoplimit for the first
1403 	 * probe packet, gateway addresses and the outgoing interface index.
1404 	 */
1405 	if (ai_dst->ai_family == AF_INET6 || (probe_all && num_v6)) {
1406 		msg6.msg_control = NULL;
1407 		msg6.msg_controllen = 0;
1408 		set_ancillary_data(&msg6, first_ttl, pr6->gwIPlist, gw_count,
1409 		    if_index);
1410 	}
1411 
1412 	/* run traceroute for all the IP addresses of the multihomed dest */
1413 	for (aip = ai_dst, i = 0; i < num_dst_IPaddrs && aip != NULL; i++) {
1414 		union any_in_addr *addrp;
1415 		if (aip->ai_family == AF_INET) {
1416 			addrp = (union any_in_addr *)
1417 			    /* LINTED E_BAD_PTR_CAST_ALIGN */
1418 			    &((struct sockaddr_in *)
1419 			    aip->ai_addr)->sin_addr;
1420 			set_sin((struct sockaddr *)pr4->to, addrp,
1421 			    aip->ai_family);
1422 			traceroute(addrp, &msg6, pr4, num_ifs4, al4);
1423 		} else {
1424 			addrp = (union any_in_addr *)
1425 			    /* LINTED E_BAD_PTR_CAST_ALIGN */
1426 			    &((struct sockaddr_in6 *)
1427 			    aip->ai_addr)->sin6_addr;
1428 			set_sin((struct sockaddr *)pr6->to, addrp,
1429 			    aip->ai_family);
1430 			traceroute(addrp, &msg6, pr6, num_ifs6, al6);
1431 		}
1432 		aip = aip->ai_next;
1433 		if (i < (num_dst_IPaddrs - 1))
1434 			(void) putchar('\n');
1435 	}
1436 }
1437 
1438 /*
1439  * set the IP address in a sockaddr struct
1440  */
1441 static void
1442 set_sin(struct sockaddr *sock, union any_in_addr *addr, int family)
1443 {
1444 	sock->sa_family = family;
1445 
1446 	if (family == AF_INET)
1447 		/* LINTED E_BAD_PTR_CAST_ALIGN */
1448 		((struct sockaddr_in *)sock)->sin_addr = addr->addr;
1449 	else
1450 		/* LINTED E_BAD_PTR_CAST_ALIGN */
1451 		((struct sockaddr_in6 *)sock)->sin6_addr = addr->addr6;
1452 }
1453 
1454 /*
1455  * returns the IF name on which the given IP address is configured
1456  */
1457 static char *
1458 device_name(struct ifaddrlist *al, int len, union any_in_addr *ip_addr,
1459     struct pr_set *pr)
1460 {
1461 	int i;
1462 	struct ifaddrlist *tmp_al;
1463 
1464 	tmp_al = al;
1465 
1466 	for (i = 0; i < len; i++, tmp_al++) {
1467 		if (memcmp(&tmp_al->addr, ip_addr, pr->addr_len) == 0) {
1468 			return (tmp_al->device);
1469 		}
1470 	}
1471 
1472 	return (NULL);
1473 }
1474 
1475 /*
1476  * Trace the route to the host with given IP address.
1477  */
1478 static void
1479 traceroute(union any_in_addr *ip_addr, struct msghdr *msg6, struct pr_set *pr,
1480     int num_ifs, struct ifaddrlist *al)
1481 {
1482 	int ttl;
1483 	int probe;
1484 	uchar_t type;				/* icmp type */
1485 	uchar_t code;				/* icmp code */
1486 	int reply;
1487 	int seq = 0;
1488 	char temp_buf[INET6_ADDRSTRLEN];	/* use for inet_ntop() */
1489 	int longjmp_return;			/* return value from longjump */
1490 	struct ip *ip = (struct ip *)packet;
1491 	boolean_t got_there = _B_FALSE;		/* we hit the destination */
1492 	static boolean_t first_pkt = _B_TRUE;
1493 	int hoplimit;				/* hoplimit for IPv6 packets */
1494 	struct in6_addr addr6;
1495 	int num_src_ifs;			/* excludes down and loopback */
1496 	struct msghdr in_msg;
1497 	struct iovec iov;
1498 	int *intp;
1499 	int sndsock;
1500 	int rcvsock;
1501 
1502 	msg6->msg_name = pr->to;
1503 	msg6->msg_namelen = sizeof (struct sockaddr_in6);
1504 	sndsock =  (pr->family == AF_INET) ? sndsock4 : sndsock6;
1505 	rcvsock =  (pr->family == AF_INET) ? rcvsock4 : rcvsock6;
1506 
1507 	/* carry out the source address selection */
1508 	if (pick_src) {
1509 		union any_in_addr src_addr;
1510 		char *dev_name;
1511 		int i;
1512 
1513 		/*
1514 		 * If there's a gateway, a routing header as a consequence, our
1515 		 * kernel picks the source address based on the first hop
1516 		 * address, rather than final destination address.
1517 		 */
1518 		if (gw_count > 0) {
1519 			(void) select_src_addr(pr->gwIPlist, &src_addr,
1520 			    pr->family);
1521 		} else {
1522 			(void) select_src_addr(ip_addr, &src_addr, pr->family);
1523 		}
1524 		set_sin(pr->from, &src_addr, pr->family);
1525 
1526 		/* filter out down and loopback interfaces */
1527 		num_src_ifs = 0;
1528 		for (i = 0; i < num_ifs; i++) {
1529 			if (!(al[i].flags & IFF_LOOPBACK) &&
1530 			    (al[i].flags & IFF_UP))
1531 				num_src_ifs++;
1532 		}
1533 
1534 		if (num_src_ifs > 1) {
1535 			dev_name = device_name(al, num_ifs, &src_addr, pr);
1536 			if (dev_name == NULL)
1537 				dev_name = "?";
1538 
1539 			Fprintf(stderr,
1540 			    "%s: Warning: Multiple interfaces found;"
1541 			    " using %s @ %s\n",
1542 			    prog, inet_ntop(pr->family,
1543 				(const void *)pr->from_sin_addr,
1544 				temp_buf, sizeof (temp_buf)),
1545 			    dev_name);
1546 		}
1547 	}
1548 
1549 	if (pr->family == AF_INET) {
1550 		outip4->ip_src = *(struct in_addr *)pr->from_sin_addr;
1551 		outip4->ip_dst = ip_addr->addr;
1552 	}
1553 
1554 	/*
1555 	 * If the hostname is an IPv6 literal address, let's not print it twice.
1556 	 */
1557 	if (pr->family == AF_INET6 &&
1558 	    inet_pton(AF_INET6, hostname, &addr6) > 0) {
1559 		Fprintf(stderr, "%s to %s", prog, hostname);
1560 	} else {
1561 		Fprintf(stderr, "%s to %s (%s)", prog, hostname,
1562 		    inet_ntop(pr->family, (const void *)ip_addr, temp_buf,
1563 			sizeof (temp_buf)));
1564 	}
1565 
1566 	if (source)
1567 		Fprintf(stderr, " from %s", source);
1568 	Fprintf(stderr, ", %d hops max, %d byte packets\n", max_ttl,
1569 	    pr->packlen);
1570 	(void) fflush(stderr);
1571 
1572 	/*
1573 	 * Setup the source routing for IPv4. For IPv6, we did the required
1574 	 * setup in the caller function, trace_it(), because it's independent
1575 	 * from the IP address of target.
1576 	 */
1577 	if (pr->family == AF_INET && gw_count > 0)
1578 		set_IPv4opt_sourcerouting(sndsock, ip_addr, pr->gwIPlist);
1579 
1580 	if (probe_all) {
1581 		/* interrupt handler sig_handler() jumps back to here */
1582 		if ((longjmp_return = setjmp(env)) != 0) {
1583 			switch (longjmp_return) {
1584 			case SIGINT:
1585 				Printf("(skipping)\n");
1586 				return;
1587 			case SIGQUIT:
1588 				Printf("(exiting)\n");
1589 				exit(EXIT_SUCCESS);
1590 			default:	/* should never happen */
1591 				exit(EXIT_FAILURE);
1592 			}
1593 		}
1594 		(void) signal(SIGINT, sig_handler);
1595 	}
1596 
1597 	for (ttl = first_ttl; ttl <= max_ttl; ++ttl) {
1598 		union any_in_addr lastaddr;
1599 		int timeouts = 0;
1600 		double rtt;		/* for statistics */
1601 		int nreceived = 0;
1602 		double rttmin, rttmax;
1603 		double rttsum, rttssq;
1604 		int unreachable;
1605 
1606 		got_there = _B_FALSE;
1607 		unreachable = 0;
1608 
1609 		/*
1610 		 * The following line clears both IPv4 and IPv6 address stored
1611 		 * in the union.
1612 		 */
1613 		lastaddr.addr6 = in6addr_any;
1614 
1615 		if ((ttl == (first_ttl + 1)) && (options & SO_DONTROUTE)) {
1616 			Fprintf(stderr,
1617 			    "%s: host %s is not on a directly-attached"
1618 			    " network\n", prog, hostname);
1619 			break;
1620 		}
1621 
1622 		Printf("%2d ", ttl);
1623 		(void) fflush(stdout);
1624 
1625 		for (probe = 0; (probe < nprobes) && (timeouts < max_timeout);
1626 		    ++probe) {
1627 			int cc;
1628 			struct timeval t1, t2;
1629 
1630 			/*
1631 			 * Put a delay before sending this probe packet. Don't
1632 			 * delay it if it's the very first packet.
1633 			 */
1634 			if (!first_pkt) {
1635 				if (delay.tv_sec > 0)
1636 					(void) sleep((uint_t)delay.tv_sec);
1637 				if (delay.tv_usec > 0)
1638 					(void) usleep(delay.tv_usec);
1639 			} else {
1640 				first_pkt = _B_FALSE;
1641 			}
1642 
1643 			(void) gettimeofday(&t1, NULL);
1644 
1645 			if (pr->family == AF_INET) {
1646 				send_probe(sndsock, pr->to, outip4, seq, ttl,
1647 				    &t1, pr->packlen);
1648 			} else {
1649 				send_probe6(sndsock, msg6, outip6, seq, ttl,
1650 				    &t1, pr->packlen);
1651 			}
1652 
1653 			/* prepare msghdr for recvmsg() */
1654 			in_msg.msg_name = pr->from;
1655 			in_msg.msg_namelen = pr->sock_size;
1656 
1657 			iov.iov_base = (char *)packet;
1658 			iov.iov_len = sizeof (packet);
1659 
1660 			in_msg.msg_iov = &iov;
1661 			in_msg.msg_iovlen = 1;
1662 
1663 			in_msg.msg_control = ancillary_data;
1664 			in_msg.msg_controllen = sizeof (ancillary_data);
1665 
1666 			while ((cc = wait_for_reply(rcvsock, &in_msg,
1667 			    &t1)) != 0) {
1668 				(void) gettimeofday(&t2, NULL);
1669 
1670 				reply = (*pr->check_reply_fn) (&in_msg, cc, seq,
1671 				    &type, &code);
1672 
1673 				in_msg.msg_controllen =
1674 				    sizeof (ancillary_data);
1675 				/* Skip short packet */
1676 				if (reply == REPLY_SHORT_PKT) {
1677 					continue;
1678 				}
1679 
1680 				timeouts = 0;
1681 
1682 				/*
1683 				 * if reply comes from a different host, print
1684 				 * the hostname
1685 				 */
1686 				if (memcmp(pr->from_sin_addr, &lastaddr,
1687 				    pr->addr_len) != 0) {
1688 					(*pr->print_addr_fn) ((uchar_t *)packet,
1689 					    cc, pr->from);
1690 					/* store the address response */
1691 					(void) memcpy(&lastaddr,
1692 					    pr->from_sin_addr, pr->addr_len);
1693 				}
1694 
1695 				rtt = deltaT(&t1, &t2);
1696 				if (collect_stat) {
1697 					record_stats(rtt, &nreceived, &rttmin,
1698 					    &rttmax, &rttsum, &rttssq);
1699 				} else {
1700 					Printf("  %.3f ms", rtt);
1701 				}
1702 
1703 				if (pr->family == AF_INET6) {
1704 					intp =
1705 					    (int *)find_ancillary_data(&in_msg,
1706 						IPPROTO_IPV6, IPV6_HOPLIMIT);
1707 					if (intp == NULL) {
1708 						Fprintf(stderr,
1709 						    "%s: can't find "
1710 						    "IPV6_HOPLIMIT ancillary "
1711 						    "data\n", prog);
1712 						exit(EXIT_FAILURE);
1713 					}
1714 					hoplimit = *intp;
1715 				}
1716 
1717 				if (reply == REPLY_GOT_TARGET) {
1718 					got_there = _B_TRUE;
1719 
1720 					if (((pr->family == AF_INET) &&
1721 					    (ip->ip_ttl <= 1)) ||
1722 					    ((pr->family == AF_INET6) &&
1723 					    (hoplimit <= 1)))
1724 						Printf(" !");
1725 				}
1726 
1727 				if (!collect_stat && showttl) {
1728 					if (pr->family == AF_INET) {
1729 						Printf(" (ttl=%d)",
1730 						    (int)ip->ip_ttl);
1731 					} else if (hoplimit != -1) {
1732 						Printf(" (hop limit=%d)",
1733 						    hoplimit);
1734 					}
1735 				}
1736 
1737 				if (reply == REPLY_GOT_OTHER) {
1738 					if ((*pr->print_icmp_other_fn)
1739 					    (type, code)) {
1740 						unreachable++;
1741 					}
1742 				}
1743 
1744 				/* special case */
1745 				if (pr->family == AF_INET &&
1746 				    type == ICMP_UNREACH &&
1747 				    code == ICMP_UNREACH_PROTOCOL)
1748 					got_there = _B_TRUE;
1749 
1750 				break;
1751 			}
1752 
1753 			seq = (seq + 1) % (MAX_SEQ + 1);
1754 
1755 			if (cc == 0) {
1756 				Printf(" *");
1757 				timeouts++;
1758 			}
1759 
1760 			(void) fflush(stdout);
1761 		}
1762 
1763 		if (collect_stat) {
1764 			print_stats(probe, nreceived, rttmin, rttmax, rttsum,
1765 			    rttssq);
1766 		}
1767 
1768 		(void) putchar('\n');
1769 
1770 		/* either we hit the target or received too many unreachables */
1771 		if (got_there ||
1772 		    (unreachable > 0 && unreachable >= nprobes - 1))
1773 			break;
1774 	}
1775 
1776 	/* Ignore the SIGINT between traceroute() runs */
1777 	if (probe_all)
1778 		(void) signal(SIGINT, SIG_IGN);
1779 }
1780 
1781 /*
1782  * for a given destination address and address family, it finds out what
1783  * source address kernel is going to pick
1784  */
1785 static void
1786 select_src_addr(union any_in_addr *dst_addr, union any_in_addr *src_addr,
1787     int family)
1788 {
1789 	int tmp_fd;
1790 	struct sockaddr *sock;
1791 	struct sockaddr_in *sin;
1792 	struct sockaddr_in6 *sin6;
1793 	size_t sock_len;
1794 
1795 	sock = (struct sockaddr *)malloc(sizeof (struct sockaddr_in6));
1796 	if (sock == NULL) {
1797 		Fprintf(stderr, "%s: malloc %s\n", prog, strerror(errno));
1798 		exit(EXIT_FAILURE);
1799 	}
1800 	(void) bzero(sock, sizeof (struct sockaddr_in6));
1801 
1802 	if (family == AF_INET) {
1803 		/* LINTED E_BAD_PTR_CAST_ALIGN */
1804 		sin = (struct sockaddr_in *)sock;
1805 		sin->sin_family = AF_INET;
1806 		sin->sin_addr = dst_addr->addr;
1807 		sin->sin_port = IPPORT_ECHO;	/* port shouldn't be 0 */
1808 		sock_len = sizeof (struct sockaddr_in);
1809 	} else {
1810 		/* LINTED E_BAD_PTR_CAST_ALIGN */
1811 		sin6 = (struct sockaddr_in6 *)sock;
1812 		sin6->sin6_family = AF_INET6;
1813 		sin6->sin6_addr = dst_addr->addr6;
1814 		sin6->sin6_port = IPPORT_ECHO;	/* port shouldn't be 0 */
1815 		sock_len = sizeof (struct sockaddr_in6);
1816 	}
1817 
1818 	/* open a UDP socket */
1819 	if ((tmp_fd = socket(family, SOCK_DGRAM, 0)) < 0) {
1820 		Fprintf(stderr, "%s: udp socket: %s\n", prog,
1821 		    strerror(errno));
1822 		exit(EXIT_FAILURE);
1823 	}
1824 
1825 	/* connect it */
1826 	if (connect(tmp_fd, sock, sock_len) < 0) {
1827 		/*
1828 		 * If there's no route to the destination, this connect() call
1829 		 * fails. We just return all-zero (wildcard) as the source
1830 		 * address, so that user can get to see "no route to dest"
1831 		 * message, as it'll try to send the probe packet out and will
1832 		 * receive ICMP unreachable.
1833 		 */
1834 		if (family == AF_INET)
1835 			src_addr->addr.s_addr = INADDR_ANY;
1836 		else
1837 			src_addr->addr6 = in6addr_any;
1838 		free(sock);
1839 		return;
1840 	}
1841 
1842 	/* get the local sock info */
1843 	if (getsockname(tmp_fd, sock, &sock_len) < 0) {
1844 		Fprintf(stderr, "%s: getsockname: %s\n", prog,
1845 		    strerror(errno));
1846 		exit(EXIT_FAILURE);
1847 	}
1848 
1849 	if (family == AF_INET) {
1850 		/* LINTED E_BAD_PTR_CAST_ALIGN */
1851 		sin = (struct sockaddr_in *)sock;
1852 		src_addr->addr = sin->sin_addr;
1853 	} else {
1854 		/* LINTED E_BAD_PTR_CAST_ALIGN */
1855 		sin6 = (struct sockaddr_in6 *)sock;
1856 		src_addr->addr6 = sin6->sin6_addr;
1857 	}
1858 
1859 	free(sock);
1860 	(void) close(tmp_fd);
1861 }
1862 
1863 /*
1864  * Checksum routine for Internet Protocol family headers (C Version)
1865  */
1866 ushort_t
1867 in_cksum(ushort_t *addr, int len)
1868 {
1869 	int nleft = len;
1870 	ushort_t *w = addr;
1871 	ushort_t answer;
1872 	int sum = 0;
1873 
1874 	/*
1875 	 *  Our algorithm is simple, using a 32 bit accumulator (sum),
1876 	 *  we add sequential 16 bit words to it, and at the end, fold
1877 	 *  back all the carry bits from the top 16 bits into the lower
1878 	 *  16 bits.
1879 	 */
1880 	while (nleft > 1)  {
1881 		sum += *w++;
1882 		nleft -= 2;
1883 	}
1884 
1885 	/* mop up an odd byte, if necessary */
1886 	if (nleft == 1)
1887 		sum += *(uchar_t *)w;
1888 
1889 	/* add back carry outs from top 16 bits to low 16 bits */
1890 	sum = (sum >> 16) + (sum & 0xffff);	/* add hi 16 to low 16 */
1891 	sum += (sum >> 16);			/* add carry */
1892 	answer = ~sum;				/* truncate to 16 bits */
1893 	return (answer);
1894 }
1895 
1896 /*
1897  * Wait until a reply arrives or timeout occurs. If packet arrived, read it
1898  * return the size of the packet read.
1899  */
1900 static int
1901 wait_for_reply(int sock, struct msghdr *msg, struct timeval *tp)
1902 {
1903 	fd_set fds;
1904 	struct timeval now, wait;
1905 	int cc = 0;
1906 	int result;
1907 
1908 	(void) FD_ZERO(&fds);
1909 	FD_SET(sock, &fds);
1910 
1911 	wait.tv_sec = tp->tv_sec + waittime;
1912 	wait.tv_usec = tp->tv_usec;
1913 	(void) gettimeofday(&now, NULL);
1914 	tv_sub(&wait, &now);
1915 
1916 	if (wait.tv_sec < 0 || wait.tv_usec < 0)
1917 		return (0);
1918 
1919 	result = select(sock + 1, &fds, (fd_set *)NULL, (fd_set *)NULL, &wait);
1920 
1921 	if (result == -1) {
1922 		if (errno != EINTR) {
1923 			Fprintf(stderr, "%s: select: %s\n", prog,
1924 			    strerror(errno));
1925 		}
1926 	} else if (result > 0)
1927 		cc = recvmsg(sock, msg, 0);
1928 
1929 	return (cc);
1930 }
1931 
1932 /*
1933  * Construct an Internet address representation. If the nflag has been supplied,
1934  * give numeric value, otherwise try for symbolic name.
1935  */
1936 char *
1937 inet_name(union any_in_addr *in, int family)
1938 {
1939 	char *cp;
1940 	static boolean_t first = _B_TRUE;
1941 	static char domain[NI_MAXHOST + 1];
1942 	static char line[NI_MAXHOST + 1];	/* assuming		*/
1943 				/* (NI_MAXHOST + 1) >= INET6_ADDRSTRLEN */
1944 	char hbuf[NI_MAXHOST];
1945 	socklen_t slen;
1946 	struct sockaddr_in sin;
1947 	struct sockaddr_in6 sin6;
1948 	struct sockaddr *sa;
1949 	int flags;
1950 
1951 	switch (family) {
1952 	case AF_INET:
1953 		slen = sizeof (struct sockaddr_in);
1954 		sin.sin_addr = in->addr;
1955 		sin.sin_port = 0;
1956 		sa = (struct sockaddr *)&sin;
1957 		break;
1958 	case AF_INET6:
1959 		slen = sizeof (struct sockaddr_in6);
1960 		sin6.sin6_addr = in->addr6;
1961 		sin6.sin6_port = 0;
1962 		sa = (struct sockaddr *)&sin6;
1963 		break;
1964 	deafult:
1965 		(void) snprintf(line, sizeof (line),
1966 		    "<invalid address family>");
1967 		return (line);
1968 	}
1969 	sa->sa_family = family;
1970 
1971 	if (first && !nflag) {
1972 		/* find out the domain name */
1973 		first = _B_FALSE;
1974 		if (gethostname(domain, MAXHOSTNAMELEN) == 0 &&
1975 		    (cp = strchr(domain, '.')) != NULL) {
1976 			(void) strncpy(domain, cp + 1, sizeof (domain) - 1);
1977 			domain[sizeof (domain) - 1] = '\0';
1978 		} else {
1979 			domain[0] = '\0';
1980 		}
1981 	}
1982 
1983 	flags = (nflag) ? NI_NUMERICHOST : NI_NAMEREQD;
1984 	if (getnameinfo(sa, slen, hbuf, sizeof (hbuf), NULL, 0, flags) != 0) {
1985 		if (inet_ntop(family, (const void *)&in->addr6,
1986 		    hbuf, sizeof (hbuf)) == NULL)
1987 			hbuf[0] = 0;
1988 	} else if (!nflag && (cp = strchr(hbuf, '.')) != NULL &&
1989 	    strcmp(cp + 1, domain) == 0) {
1990 		*cp = '\0';
1991 	}
1992 	(void) strlcpy(line, hbuf, sizeof (line));
1993 
1994 	return (line);
1995 }
1996 
1997 /*
1998  * return the difference (in msec) between two time values
1999  */
2000 static double
2001 deltaT(struct timeval *t1p, struct timeval *t2p)
2002 {
2003 	double dt;
2004 
2005 	dt = (double)(t2p->tv_sec - t1p->tv_sec) * 1000.0 +
2006 	    (double)(t2p->tv_usec - t1p->tv_usec) / 1000.0;
2007 	return (dt);
2008 }
2009 
2010 /*
2011  * Subtract 2 timeval structs:  out = out - in.
2012  * Out is assumed to be >= in.
2013  */
2014 static void
2015 tv_sub(struct timeval *out, struct timeval *in)
2016 {
2017 	if ((out->tv_usec -= in->tv_usec) < 0)   {
2018 		--out->tv_sec;
2019 		out->tv_usec += 1000000;
2020 	}
2021 	out->tv_sec -= in->tv_sec;
2022 }
2023 
2024 /*
2025  * record statistics
2026  */
2027 static void
2028 record_stats(double rtt, int *nreceived, double *rttmin, double *rttmax,
2029     double *rttsum, double *rttssq)
2030 {
2031 	if (*nreceived == 0) {
2032 		*rttmin = rtt;
2033 		*rttmax = rtt;
2034 		*rttsum = rtt;
2035 		*rttssq = rtt * rtt;
2036 	} else {
2037 		if (rtt < *rttmin)
2038 			*rttmin = rtt;
2039 
2040 		if (rtt > *rttmax)
2041 			*rttmax = rtt;
2042 
2043 		*rttsum += rtt;
2044 		*rttssq += rtt * rtt;
2045 	}
2046 
2047 	(*nreceived)++;
2048 }
2049 
2050 /*
2051  * display statistics
2052  */
2053 static void
2054 print_stats(int ntransmitted, int nreceived, double rttmin, double rttmax,
2055     double rttsum, double rttssq)
2056 {
2057 	double rttavg;			/* average round-trip time */
2058 	double rttstd;			/* rtt standard deviation */
2059 
2060 	if (ntransmitted > 0 && ntransmitted >= nreceived) {
2061 		int missed = ntransmitted - nreceived;
2062 		double loss = 100 * (double)missed / (double)ntransmitted;
2063 
2064 		if (nreceived > 0) {
2065 			rttavg = rttsum / nreceived;
2066 			rttstd = rttssq - (rttavg * rttsum);
2067 			rttstd = xsqrt(rttstd / nreceived);
2068 
2069 			Printf("  %.3f", rttmin);
2070 			Printf("/%.3f", rttavg);
2071 			Printf("/%.3f", rttmax);
2072 
2073 			Printf(" (%.3f) ms ", rttstd);
2074 		}
2075 
2076 		Printf(" %d/%d pkts", nreceived, ntransmitted);
2077 
2078 		if (nreceived == 0)
2079 			Printf(" (100%% loss)");
2080 		else
2081 			Printf(" (%.2g%% loss)", loss);
2082 	}
2083 }
2084 
2085 /*
2086  * square root function
2087  */
2088 double
2089 xsqrt(double y)
2090 {
2091 	double t, x;
2092 
2093 	if (y <= 0) {
2094 		return (0.0);
2095 	}
2096 
2097 	x = (y < 1.0) ? 1.0 : y;
2098 	do {
2099 		t = x;
2100 		x = (t + (y/t))/2.0;
2101 	} while (0 < x && x < t);
2102 
2103 	return (x);
2104 }
2105 
2106 /*
2107  * String to double with optional min and max.
2108  */
2109 static double
2110 str2dbl(const char *str, const char *what, double mi, double ma)
2111 {
2112 	double val;
2113 	char *ep;
2114 
2115 	errno = 0;
2116 
2117 	val = strtod(str, &ep);
2118 	if (errno != 0 || *ep != '\0') {
2119 		Fprintf(stderr, "%s: \"%s\" bad value for %s \n",
2120 		    prog, str, what);
2121 		exit(EXIT_FAILURE);
2122 	}
2123 	if (val < mi && mi >= 0) {
2124 		Fprintf(stderr, "%s: %s must be >= %f\n", prog, what, mi);
2125 		exit(EXIT_FAILURE);
2126 	}
2127 	if (val > ma && ma >= 0) {
2128 		Fprintf(stderr, "%s: %s must be <= %f\n", prog, what, ma);
2129 		exit(EXIT_FAILURE);
2130 	}
2131 	return (val);
2132 }
2133 
2134 /*
2135  * String to int with optional min and max. Handles decimal and hex.
2136  */
2137 static int
2138 str2int(const char *str, const char *what, int mi, int ma)
2139 {
2140 	const char *cp;
2141 	int val;
2142 	char *ep;
2143 
2144 	errno = 0;
2145 
2146 	if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X')) {
2147 		cp = str + 2;
2148 		val = (int)strtol(cp, &ep, 16);
2149 	} else {
2150 		val = (int)strtol(str, &ep, 10);
2151 	}
2152 	if (errno != 0 || *ep != '\0') {
2153 		Fprintf(stderr, "%s: \"%s\" bad value for %s \n",
2154 		    prog, str, what);
2155 		exit(EXIT_FAILURE);
2156 	}
2157 	if (val < mi && mi >= 0) {
2158 		if (mi == 0) {
2159 			Fprintf(stderr, "%s: %s must be >= %d\n",
2160 			    prog, what, mi);
2161 		} else {
2162 			Fprintf(stderr, "%s: %s must be > %d\n",
2163 			    prog, what, mi - 1);
2164 		}
2165 		exit(EXIT_FAILURE);
2166 	}
2167 	if (val > ma && ma >= 0) {
2168 		Fprintf(stderr, "%s: %s must be <= %d\n", prog, what, ma);
2169 		exit(EXIT_FAILURE);
2170 	}
2171 	return (val);
2172 }
2173 
2174 /*
2175  * This is the interrupt handler for SIGINT and SIGQUIT. It's completely handled
2176  * where it jumps to.
2177  */
2178 static void
2179 sig_handler(int sig)
2180 {
2181 	longjmp(env, sig);
2182 }
2183 
2184 /*
2185  * display the usage of traceroute
2186  */
2187 static void
2188 usage(void)
2189 {
2190 	Fprintf(stderr, "Usage: %s [-adFIlnSvx] [-A address_family] "
2191 "[-c traffic_class] \n"
2192 "\t[-f first_hop] [-g gateway [-g gateway ...]| -r] [-i iface]\n"
2193 "\t[-L flow_label] [-m max_hop] [-P pause_sec] [-p port] [-Q max_timeout]\n"
2194 "\t[-q nqueries] [-s src_addr] [-t tos] [-w wait_time] host [packetlen]\n",
2195 		prog);
2196 	exit(EXIT_FAILURE);
2197 }
2198